Commit Graph

2467 Commits

Author SHA1 Message Date
Filipe Manana
ac3c0d36a2 btrfs: make fiemap more efficient and accurate reporting extent sharedness
The current fiemap implementation does not scale very well with the number
of extents a file has. This is both because the main algorithm to find out
the extents has a high algorithmic complexity and because for each extent
we have to check if it's shared. This second part, checking if an extent
is shared, is significantly improved by the two previous patches in this
patchset, while the first part is improved by this specific patch. Every
now and then we get reports from users mentioning fiemap is too slow or
even unusable for files with a very large number of extents, such as the
two recent reports referred to by the Link tags at the bottom of this
change log.

To understand why the part of finding which extents a file has is very
inefficient, consider the example of doing a full ranged fiemap against
a file that has over 100K extents (normal for example for a file with
more than 10G of data and using compression, which limits the extent size
to 128K). When we enter fiemap at extent_fiemap(), the following happens:

1) Before entering the main loop, we call get_extent_skip_holes() to get
   the first extent map. This leads us to btrfs_get_extent_fiemap(), which
   in turn calls btrfs_get_extent(), to find the first extent map that
   covers the file range [0, LLONG_MAX).

   btrfs_get_extent() will first search the inode's extent map tree, to
   see if we have an extent map there that covers the range. If it does
   not find one, then it will search the inode's subvolume b+tree for a
   fitting file extent item. After finding the file extent item, it will
   allocate an extent map, fill it in with information extracted from the
   file extent item, and add it to the inode's extent map tree (which
   requires a search for insertion in the tree).

2) Then we enter the main loop at extent_fiemap(), emit the details of
   the extent, and call again get_extent_skip_holes(), with a start
   offset matching the end of the extent map we previously processed.

   We end up at btrfs_get_extent() again, will search the extent map tree
   and then search the subvolume b+tree for a file extent item if we could
   not find an extent map in the extent tree. We allocate an extent map,
   fill it in with the details in the file extent item, and then insert
   it into the extent map tree (yet another search in this tree).

3) The second step is repeated over and over, until we have processed the
   whole file range. Each iteration ends at btrfs_get_extent(), which
   does a red black tree search on the extent map tree, then searches the
   subvolume b+tree, allocates an extent map and then does another search
   in the extent map tree in order to insert the extent map.

   In the best scenario we have all the extent maps already in the extent
   tree, and so for each extent we do a single search on a red black tree,
   so we have a complexity of O(n log n).

   In the worst scenario we don't have any extent map already loaded in
   the extent map tree, or have very few already there. In this case the
   complexity is much higher since we do:

   - A red black tree search on the extent map tree, which has O(log n)
     complexity, initially very fast since the tree is empty or very
     small, but as we end up allocating extent maps and adding them to
     the tree when we don't find them there, each subsequent search on
     the tree gets slower, since it's getting bigger and bigger after
     each iteration.

   - A search on the subvolume b+tree, also O(log n) complexity, but it
     has items for all inodes in the subvolume, not just items for our
     inode. Plus on a filesystem with concurrent operations on other
     inodes, we can block doing the search due to lock contention on
     b+tree nodes/leaves.

   - Allocate an extent map - this can block, and can also fail if we
     are under serious memory pressure.

   - Do another search on the extent maps red black tree, with the goal
     of inserting the extent map we just allocated. Again, after every
     iteration this tree is getting bigger by 1 element, so after many
     iterations the searches are slower and slower.

   - We will not need the allocated extent map anymore, so it's pointless
     to add it to the extent map tree. It's just wasting time and memory.

   In short we end up searching the extent map tree multiple times, on a
   tree that is growing bigger and bigger after each iteration. And
   besides that we visit the same leaf of the subvolume b+tree many times,
   since a leaf with the default size of 16K can easily have more than 200
   file extent items.

This is very inefficient overall. This patch changes the algorithm to
instead iterate over the subvolume b+tree, visiting each leaf only once,
and only searching in the extent map tree for file ranges that have holes
or prealloc extents, in order to figure out if we have delalloc there.
It will never allocate an extent map and add it to the extent map tree.
This is very similar to what was previously done for the lseek's hole and
data seeking features.

Also, the current implementation relying on extent maps for figuring out
which extents we have is not correct. This is because extent maps can be
merged even if they represent different extents - we do this to minimize
memory utilization and keep extent map trees smaller. For example if we
have two extents that are contiguous on disk, once we load the two extent
maps, they get merged into a single one - however if only one of the
extents is shared, we end up reporting both as shared or both as not
shared, which is incorrect.

This reproducer triggers that bug:

    $ cat fiemap-bug.sh
    #!/bin/bash

    DEV=/dev/sdj
    MNT=/mnt/sdj

    mkfs.btrfs -f $DEV
    mount $DEV $MNT

    # Create a file with two 256K extents.
    # Since there is no other write activity, they will be contiguous,
    # and their extent maps merged, despite having two distinct extents.
    xfs_io -f -c "pwrite -S 0xab 0 256K" \
              -c "fsync" \
              -c "pwrite -S 0xcd 256K 256K" \
              -c "fsync" \
              $MNT/foo

    # Now clone only the second extent into another file.
    xfs_io -f -c "reflink $MNT/foo 256K 0 256K" $MNT/bar

    # Filefrag will report a single 512K extent, and say it's not shared.
    echo
    filefrag -v $MNT/foo

    umount $MNT

Running the reproducer:

    $ ./fiemap-bug.sh
    wrote 262144/262144 bytes at offset 0
    256 KiB, 64 ops; 0.0038 sec (65.479 MiB/sec and 16762.7030 ops/sec)
    wrote 262144/262144 bytes at offset 262144
    256 KiB, 64 ops; 0.0040 sec (61.125 MiB/sec and 15647.9218 ops/sec)
    linked 262144/262144 bytes at offset 0
    256 KiB, 1 ops; 0.0002 sec (1.034 GiB/sec and 4237.2881 ops/sec)

    Filesystem type is: 9123683e
    File size of /mnt/sdj/foo is 524288 (128 blocks of 4096 bytes)
     ext:     logical_offset:        physical_offset: length:   expected: flags:
       0:        0..     127:       3328..      3455:    128:             last,eof
    /mnt/sdj/foo: 1 extent found

We end up reporting that we have a single 512K that is not shared, however
we have two 256K extents, and the second one is shared. Changing the
reproducer to clone instead the first extent into file 'bar', makes us
report a single 512K extent that is shared, which is algo incorrect since
we have two 256K extents and only the first one is shared.

This patch is part of a larger patchset that is comprised of the following
patches:

    btrfs: allow hole and data seeking to be interruptible
    btrfs: make hole and data seeking a lot more efficient
    btrfs: remove check for impossible block start for an extent map at fiemap
    btrfs: remove zero length check when entering fiemap
    btrfs: properly flush delalloc when entering fiemap
    btrfs: allow fiemap to be interruptible
    btrfs: rename btrfs_check_shared() to a more descriptive name
    btrfs: speedup checking for extent sharedness during fiemap
    btrfs: skip unnecessary extent buffer sharedness checks during fiemap
    btrfs: make fiemap more efficient and accurate reporting extent sharedness

The patchset was tested on a machine running a non-debug kernel (Debian's
default config) and compared the tests below on a branch without the
patchset versus the same branch with the whole patchset applied.

The following test for a large compressed file without holes:

    $ cat fiemap-perf-test.sh
    #!/bin/bash

    DEV=/dev/sdi
    MNT=/mnt/sdi

    mkfs.btrfs -f $DEV
    mount -o compress=lzo $DEV $MNT

    # 40G gives 327680 128K file extents (due to compression).
    xfs_io -f -c "pwrite -S 0xab -b 1M 0 20G" $MNT/foobar

    umount $MNT
    mount -o compress=lzo $DEV $MNT

    start=$(date +%s%N)
    filefrag $MNT/foobar
    end=$(date +%s%N)
    dur=$(( (end - start) / 1000000 ))
    echo "fiemap took $dur milliseconds (metadata not cached)"

    start=$(date +%s%N)
    filefrag $MNT/foobar
    end=$(date +%s%N)
    dur=$(( (end - start) / 1000000 ))
    echo "fiemap took $dur milliseconds (metadata cached)"

    umount $MNT

Before patchset:

    $ ./fiemap-perf-test.sh
    (...)
    /mnt/sdi/foobar: 327680 extents found
    fiemap took 3597 milliseconds (metadata not cached)
    /mnt/sdi/foobar: 327680 extents found
    fiemap took 2107 milliseconds (metadata cached)

After patchset:

    $ ./fiemap-perf-test.sh
    (...)
    /mnt/sdi/foobar: 327680 extents found
    fiemap took 1214 milliseconds (metadata not cached)
    /mnt/sdi/foobar: 327680 extents found
    fiemap took 684 milliseconds (metadata cached)

That's a speedup of about 3x for both cases (no metadata cached and all
metadata cached).

The test provided by Pavel (first Link tag at the bottom), which uses
files with a large number of holes, was also used to measure the gains,
and it consists on a small C program and a shell script to invoke it.
The C program is the following:

    $ cat pavels-test.c
    #include <stdio.h>
    #include <unistd.h>
    #include <stdlib.h>
    #include <fcntl.h>

    #include <sys/stat.h>
    #include <sys/time.h>
    #include <sys/ioctl.h>

    #include <linux/fs.h>
    #include <linux/fiemap.h>

    #define FILE_INTERVAL (1<<13) /* 8Kb */

    long long interval(struct timeval t1, struct timeval t2)
    {
        long long val = 0;
        val += (t2.tv_usec - t1.tv_usec);
        val += (t2.tv_sec - t1.tv_sec) * 1000 * 1000;
        return val;
    }

    int main(int argc, char **argv)
    {
        struct fiemap fiemap = {};
        struct timeval t1, t2;
        char data = 'a';
        struct stat st;
        int fd, off, file_size = FILE_INTERVAL;

        if (argc != 3 && argc != 2) {
                printf("usage: %s <path> [size]\n", argv[0]);
                return 1;
        }

        if (argc == 3)
                file_size = atoi(argv[2]);
        if (file_size < FILE_INTERVAL)
                file_size = FILE_INTERVAL;
        file_size -= file_size % FILE_INTERVAL;

        fd = open(argv[1], O_RDWR | O_CREAT | O_TRUNC, 0644);
        if (fd < 0) {
            perror("open");
            return 1;
        }

        for (off = 0; off < file_size; off += FILE_INTERVAL) {
            if (pwrite(fd, &data, 1, off) != 1) {
                perror("pwrite");
                close(fd);
                return 1;
            }
        }

        if (ftruncate(fd, file_size)) {
            perror("ftruncate");
            close(fd);
            return 1;
        }

        if (fstat(fd, &st) < 0) {
            perror("fstat");
            close(fd);
            return 1;
        }

        printf("size: %ld\n", st.st_size);
        printf("actual size: %ld\n", st.st_blocks * 512);

        fiemap.fm_length = FIEMAP_MAX_OFFSET;
        gettimeofday(&t1, NULL);
        if (ioctl(fd, FS_IOC_FIEMAP, &fiemap) < 0) {
            perror("fiemap");
            close(fd);
            return 1;
        }
        gettimeofday(&t2, NULL);

        printf("fiemap: fm_mapped_extents = %d\n",
               fiemap.fm_mapped_extents);
        printf("time = %lld us\n", interval(t1, t2));

        close(fd);
        return 0;
    }

    $ gcc -o pavels_test pavels_test.c

And the wrapper shell script:

    $ cat fiemap-pavels-test.sh

    #!/bin/bash

    DEV=/dev/sdi
    MNT=/mnt/sdi

    mkfs.btrfs -f -O no-holes $DEV
    mount $DEV $MNT

    echo
    echo "*********** 256M ***********"
    echo

    ./pavels-test $MNT/testfile $((1 << 28))
    echo
    ./pavels-test $MNT/testfile $((1 << 28))

    echo
    echo "*********** 512M ***********"
    echo

    ./pavels-test $MNT/testfile $((1 << 29))
    echo
    ./pavels-test $MNT/testfile $((1 << 29))

    echo
    echo "*********** 1G ***********"
    echo

    ./pavels-test $MNT/testfile $((1 << 30))
    echo
    ./pavels-test $MNT/testfile $((1 << 30))

    umount $MNT

Running his reproducer before applying the patchset:

    *********** 256M ***********

    size: 268435456
    actual size: 134217728
    fiemap: fm_mapped_extents = 32768
    time = 4003133 us

    size: 268435456
    actual size: 134217728
    fiemap: fm_mapped_extents = 32768
    time = 4895330 us

    *********** 512M ***********

    size: 536870912
    actual size: 268435456
    fiemap: fm_mapped_extents = 65536
    time = 30123675 us

    size: 536870912
    actual size: 268435456
    fiemap: fm_mapped_extents = 65536
    time = 33450934 us

    *********** 1G ***********

    size: 1073741824
    actual size: 536870912
    fiemap: fm_mapped_extents = 131072
    time = 224924074 us

    size: 1073741824
    actual size: 536870912
    fiemap: fm_mapped_extents = 131072
    time = 217239242 us

Running it after applying the patchset:

    *********** 256M ***********

    size: 268435456
    actual size: 134217728
    fiemap: fm_mapped_extents = 32768
    time = 29475 us

    size: 268435456
    actual size: 134217728
    fiemap: fm_mapped_extents = 32768
    time = 29307 us

    *********** 512M ***********

    size: 536870912
    actual size: 268435456
    fiemap: fm_mapped_extents = 65536
    time = 58996 us

    size: 536870912
    actual size: 268435456
    fiemap: fm_mapped_extents = 65536
    time = 59115 us

    *********** 1G ***********

    size: 1073741824
    actual size: 536870912
    fiemap: fm_mapped_extents = 116251
    time = 124141 us

    size: 1073741824
    actual size: 536870912
    fiemap: fm_mapped_extents = 131072
    time = 119387 us

The speedup is massive, both on the first fiemap call and on the second
one as well, as his test creates files with many holes and small extents
(every extent follows a hole and precedes another hole).

For the 256M file we go from 4 seconds down to 29 milliseconds in the
first run, and then from 4.9 seconds down to 29 milliseconds again in the
second run, a speedup of 138x and 169x, respectively.

For the 512M file we go from 30.1 seconds down to 59 milliseconds in the
first run, and then from 33.5 seconds down to 59 milliseconds again in the
second run, a speedup of 510x and 568x, respectively.

For the 1G file, we go from 225 seconds down to 124 milliseconds in the
first run, and then from 217 seconds down to 119 milliseconds in the
second run, a speedup of 1815x and 1824x, respectively.

Reported-by: Pavel Tikhomirov <ptikhomirov@virtuozzo.com>
Link: https://lore.kernel.org/linux-btrfs/21dd32c6-f1f9-f44a-466a-e18fdc6788a7@virtuozzo.com/
Reported-by: Dominique MARTINET <dominique.martinet@atmark-techno.com>
Link: https://lore.kernel.org/linux-btrfs/Ysace25wh5BbLd5f@atmark-techno.com/
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-09-26 12:28:01 +02:00
Filipe Manana
33a86cfa17 btrfs: properly flush delalloc when entering fiemap
If the flag FIEMAP_FLAG_SYNC is passed to fiemap, it means all delalloc
should be flushed and writeback complete. We call the generic helper
fiemap_prep() which does a filemap_write_and_wait() in case that flag is
given, however that is not enough if we have compression. Because a
single filemap_fdatawrite_range() only starts compression (in an async
thread) and therefore returns before the compression is done and writeback
is started.

So make btrfs_fiemap(), actually wait for all writeback to start and
complete if FIEMAP_FLAG_SYNC is set. We start and wait for writeback
on the whole possible file range, from 0 to LLONG_MAX, because that is
what the generic code at fiemap_prep() does.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-09-26 12:28:00 +02:00
Christoph Hellwig
917f32a235 btrfs: give struct btrfs_bio a real end_io handler
Currently btrfs_bio end I/O handling is a bit of a mess.  The bi_end_io
handler and bi_private pointer of the embedded struct bio are both used
to handle the completion of the high-level btrfs_bio and for the I/O
completion for the low-level device that the embedded bio ends up being
sent to.

To support this bi_end_io and bi_private are saved into the
btrfs_io_context structure and then restored after the bio sent to the
underlying device has completed the actual I/O.

Untangle this by adding an end I/O handler and private data to struct
btrfs_bio for the high-level btrfs_bio based completions, and leave the
actual bio bi_end_io handler and bi_private pointer entirely to the
low-level device I/O.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Tested-by: Nikolay Borisov <nborisov@suse.com>
Tested-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-09-26 12:27:59 +02:00
Christoph Hellwig
6b42f5e343 btrfs: pass the operation to btrfs_bio_alloc
Pass the operation to btrfs_bio_alloc, matching what bio_alloc_bioset
set does.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Tested-by: Nikolay Borisov <nborisov@suse.com>
Tested-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-09-26 12:27:58 +02:00
Ethan Lien
52b029f427 btrfs: remove unnecessary EXTENT_UPTODATE state in buffered I/O path
After we copied data to page cache in buffered I/O, we
1. Insert a EXTENT_UPTODATE state into inode's io_tree, by
   endio_readpage_release_extent(), set_extent_delalloc() or
   set_extent_defrag().
2. Set page uptodate before we unlock the page.

But the only place we check io_tree's EXTENT_UPTODATE state is in
btrfs_do_readpage(). We know we enter btrfs_do_readpage() only when we
have a non-uptodate page, so it is unnecessary to set EXTENT_UPTODATE.

For example, when performing a buffered random read:

	fio --rw=randread --ioengine=libaio --direct=0 --numjobs=4 \
		--filesize=32G --size=4G --bs=4k --name=job \
		--filename=/mnt/file --name=job

Then check how many extent_state in io_tree:

	cat /proc/slabinfo | grep btrfs_extent_state | awk '{print $2}'

w/o this patch, we got 640567 btrfs_extent_state.
w/  this patch, we got    204 btrfs_extent_state.

Maintaining such a big tree brings overhead since every I/O needs to insert
EXTENT_LOCKED, insert EXTENT_UPTODATE, then remove EXTENT_LOCKED. And in
every insert or remove, we need to lock io_tree, do tree search, alloc or
dealloc extent states. By removing unnecessary EXTENT_UPTODATE, we keep
io_tree in a minimal size and reduce overhead when performing buffered I/O.

Reviewed-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Robbie Ko <robbieko@synology.com>
Signed-off-by: Ethan Lien <ethanlien@synology.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-09-26 12:27:57 +02:00
Omar Sandoval
d1f68ba069 btrfs: rename btrfs_insert_file_extent() to btrfs_insert_hole_extent()
btrfs_insert_file_extent() is only ever used to insert holes, so rename
it and remove the redundant parameters.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Omar Sandoval <osandov@osandov.com>
Signed-off-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-09-26 12:27:54 +02:00
Ioannis Angelakopoulos
5f4403e10f btrfs: add lockdep annotations for the ordered extents wait event
This wait event is very similar to the pending ordered wait event in the
sense that it occurs in a different context than the condition signaling
for the event. The signaling occurs in btrfs_remove_ordered_extent()
while the wait event is implemented in btrfs_start_ordered_extent() in
fs/btrfs/ordered-data.c

However, in this case a thread must not acquire the lockdep map for the
ordered extents wait event when the ordered extent is related to a free
space inode. That is because lockdep creates dependencies between locks
acquired both in execution paths related to normal inodes and paths
related to free space inodes, thus leading to false positives.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Ioannis Angelakopoulos <iangelak@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-09-26 12:27:53 +02:00
Miklos Szeredi
863f144f12 vfs: open inside ->tmpfile()
This is in preparation for adding tmpfile support to fuse, which requires
that the tmpfile creation and opening are done as a single operation.

Replace the 'struct dentry *' argument of i_op->tmpfile with
'struct file *'.

Call finish_open_simple() as the last thing in ->tmpfile() instances (may
be omitted in the error case).

Change d_tmpfile() argument to 'struct file *' as well to make callers more
readable.

Reviewed-by: Christian Brauner (Microsoft) <brauner@kernel.org>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2022-09-24 07:00:00 +02:00
Linus Torvalds
9b45094954 for-6.0-rc4-tag
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEE8rQSAMVO+zA4DBdWxWXV+ddtWDsFAmMaPukACgkQxWXV+ddt
 WDsWKw/+IcpMsb08sjudn4dtFQ3HSA1E+dOYDzXwUJTS7ZpZhLRniLe1XQwHxe4D
 7DUQA+e1RKGq4+TiznoLhaG/YCCcrLPZL/1aWhwO0M5Wj6BCIxSUa00BJNpxyBMw
 kWb9vQltc5w5zJXHeIr7m2ByzT+YIl0v1lf2GQrJVieHhGiKslfkJHLoJt49oJ0L
 9ka183VR/OCi/3uxUw6NMAjfv+0OGEsFZX/CF8Vo64IKg0I0Q248H4enZt43aDHA
 dQDapAyAr4f6RLDs6ULS2GSzKfZIKMLHlvSeg1BSPyUt/NZFVlC0VwVX0NmwP62a
 5NECYdimlQOGSlaahNEQpLIiyNYboi3Mq7m63BofWduDQanpnM1FByln9JVEizlm
 VuUs3+O0CMp81HecSk3VbSe3ukO2fqAdQjM5cdpRx30TYu7WRiYNE3aHchgLmXLP
 0zw9JV6ePg04Mstx+/3lo8D/X/7fMAT3NrqYmuImoekFWbdJfsiUtgdXNOglT9dt
 6lb1/0jBEbdiXnQ/jT1OreGwSdGZqkEKF4OE26kPRxURyTDESzglNVyhXmshIANC
 qnNuUFGea5d7LbyozYyfdcsQS7rEqLVKmUWrOb/3O/K1947/DegYodnhRwjCUSS7
 iUaetkYUWxHa7U9303KneCUAyLEf1S8NXRPIObL6YIw7D09wato=
 =WD7B
 -----END PGP SIGNATURE-----

Merge tag 'for-6.0-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs fixes from David Sterba:
 "A few more fixes to zoned mode and one regression fix for chunk limit:

    - Zoned mode fixes:
        - fix how wait/wake up is done when finishing zone
        - fix zone append limit in emulated mode
        - fix mount on devices with conventional zones

   - fix regression, user settable data chunk limit got accidentally
     lowered and causes allocation problems on some profiles (raid0,
     raid1)"

* tag 'for-6.0-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: fix the max chunk size and stripe length calculation
  btrfs: zoned: fix mounting with conventional zones
  btrfs: zoned: set pseudo max append zone limit in zone emulation mode
  btrfs: zoned: fix API misuse of zone finish waiting
2022-09-09 07:54:19 -04:00
Naohiro Aota
d5b81ced74 btrfs: zoned: fix API misuse of zone finish waiting
The commit 2ce543f478 ("btrfs: zoned: wait until zone is finished when
allocation didn't progress") implemented a zone finish waiting mechanism
to the write path of zoned mode. However, using
wait_var_event()/wake_up_all() on fs_info->zone_finish_wait is wrong and
wait_var_event() just hangs because no one ever wakes it up once it goes
into sleep.

Instead, we can simply use wait_on_bit_io() and clear_and_wake_up_bit()
on fs_info->flags with a proper barrier installed.

Fixes: 2ce543f478 ("btrfs: zoned: wait until zone is finished when allocation didn't progress")
CC: stable@vger.kernel.org # 5.16+
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-09-05 15:32:21 +02:00
Linus Torvalds
8379c0b31f for-6.0-rc3-tag
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEE8rQSAMVO+zA4DBdWxWXV+ddtWDsFAmMLY9oACgkQxWXV+ddt
 WDue/w/8C3ZF8nLAI/sMrUpef2vSD62bvkKRRS45wzR2uod6yc0Fle9upzBssJQZ
 qO3mQ53+QV+imCq7dY5mmtmwCUJNmbV5gbiMoF1OoV9TYtpZb/NIDklSX8se2eJX
 drdAWQr2pYwU2M4duA4IEW08TvQ2TFh0JiqMi0aYM5apyL80uv3WniOu+xpRipA3
 CMFAnDqayIgQ5OIsedqNy2MBLBopodUL5PZv/H7/g6KSKIuAZP9zgg1eKPfaz2t3
 HO183ubmMbVtxgxeu+EnvCkg/iQ5hQiuGmyi0FLYMs/A6/NglwBnIJU5jCMQhcp6
 HO5+FSUn6lHQetVzt2uHb9Lo+gX4FtCaHqVv1bXT62lnmDsZO1D7RVSg1Fra+CY+
 jJmi8vvIbfbYlSZPZlJANoWe8ODOMVPk+pM4SFHlxOWGAY6HViX2RfHnIjNj5x9O
 iDSTGvH6++nBF1Wu2/Xja/VKZ1avxRyTu2srW8JOF62j/tTU/EoPJcO9rxXOBBmC
 Hi4UmJ690p3h5xZeeiyE8CmaSlPtfdCcnc/97FnusEjBao9O7THX0PCDVJX6VBkm
 hVk01Z6+az1UNcD18KecvCpKYF/At4WpjaUGgf7q+LBfJXuXA6jfzOVDJMKV3TFd
 n1yMFg+duGj90l8gT0aa/VQiBlUlnzQKz6ceqyKkPccwveNis6I=
 =p8YV
 -----END PGP SIGNATURE-----

Merge tag 'for-6.0-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs fixes from David Sterba:
 "Fixes:

   - check that subvolume is writable when changing xattrs from security
     namespace

   - fix memory leak in device lookup helper

   - update generation of hole file extent item when merging holes

   - fix space cache corruption and potential double allocations; this
     is a rare bug but can be serious once it happens, stable backports
     and analysis tool will be provided

   - fix error handling when deleting root references

   - fix crash due to assert when attempting to cancel suspended device
     replace, add message what to do if mount fails due to missing
     replace item

  Regressions:

   - don't merge pages into bio if their page offset is not contiguous

   - don't allow large NOWAIT direct reads, this could lead to short
     reads eg. in io_uring"

* tag 'for-6.0-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: add info when mount fails due to stale replace target
  btrfs: replace: drop assert for suspended replace
  btrfs: fix silent failure when deleting root reference
  btrfs: fix space cache corruption and potential double allocations
  btrfs: don't allow large NOWAIT direct reads
  btrfs: don't merge pages into bio if their page offset is not contiguous
  btrfs: update generation of hole file extent item when merging holes
  btrfs: fix possible memory leak in btrfs_get_dev_args_from_path()
  btrfs: check if root is readonly while setting security xattr
2022-08-28 10:44:04 -07:00
Josef Bacik
79d3d1d12e btrfs: don't allow large NOWAIT direct reads
Dylan and Jens reported a problem where they had an io_uring test that
was returning short reads, and bisected it to ee5b46a353 ("btrfs:
increase direct io read size limit to 256 sectors").

The root cause is their test was doing larger reads via io_uring with
NOWAIT and async.  This was triggering a page fault during the direct
read, however the first page was able to work just fine and thus we
submitted a 4k read for a larger iocb.

Btrfs allows for partial IO's in this case specifically because we don't
allow page faults, and thus we'll attempt to do any io that we can,
submit what we could, come back and fault in the rest of the range and
try to do the remaining IO.

However for !is_sync_kiocb() we'll call ->ki_complete() as soon as the
partial dio is done, which is incorrect.  In the sync case we can exit
the iomap code, submit more io's, and return with the amount of IO we
were able to complete successfully.

We were always doing short reads in this case, but for NOWAIT we were
getting saved by the fact that we were limiting direct reads to
sectorsize, and if we were larger than that we would return EAGAIN.

Fix the regression by simply returning EAGAIN in the NOWAIT case with
larger reads, that way io_uring can retry and get the larger IO and have
the fault logic handle everything properly.

This still leaves the AIO short read case, but that existed before this
change.  The way to properly fix this would be to handle partial iocb
completions, but that's a lot of work, for now deal with the regression
in the most straightforward way possible.

Reported-by: Dylan Yudaken <dylany@fb.com>
Fixes: ee5b46a353 ("btrfs: increase direct io read size limit to 256 sectors")
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-08-22 18:08:07 +02:00
Linus Torvalds
353767e4aa for-5.20-tag
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEE8rQSAMVO+zA4DBdWxWXV+ddtWDsFAmLnyNUACgkQxWXV+ddt
 WDt9vA/9HcF+v5EkknyW07tatTap/Hm/ZB86Z5OZi6ikwIEcHsWhp3rUICejm88e
 GecDPIluDtCtyD6x4stuqkwOm22aDP5q2T9H6+gyw92ozyb436OV1Z8IrmftzXKY
 EpZO70PHZT+E6E/WYvyoTmmoCrjib7YlqCWZZhSLUFpsqqlOInmHEH49PW6KvM4r
 acUZ/RxHurKdmI3kNY6ECbAQl6CASvtTdYcVCx8fT2zN0azoLIQxpYa7n/9ca1R6
 8WnYilCbLbNGtcUXvO2M3tMZ4/5kvxrwQsUn93ccCJYuiN0ASiDXbLZ2g4LZ+n56
 JGu+y5v5oBwjpVf+46cuvnENP5BQ61594WPseiVjrqODWnPjN28XkcVC0XmPsiiZ
 lszeHO2cuIrIFoCah8ELMl8usu8+qxfXmPxIXtPu9rEyKsDtOjxVYc8SMXqLp0qQ
 qYtBoFm0JcZHqtZRpB+dhQ37/xXtH4ljUi/mI6x8iALVujeR273URs7yO9zgIdeW
 uZoFtbwpHFLUk+TL7Ku82/zOXp3fCwtDpNmlYbxeMbea/be3ShjncM4+mYzvHYri
 dYON2LFrq+mnRDqtIXTCaAYwX7zU8Y18Ev9QwlNll8dKlKwS89+jpqLoa+eVYy3c
 /HitHFza70KxmOj4dvDVZlzDpPvl7kW1UBkmskg4u3jnNWzedkM=
 =sS1q
 -----END PGP SIGNATURE-----

Merge tag 'for-5.20-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs updates from David Sterba:
 "This brings some long awaited changes, the send protocol bump,
  otherwise lots of small improvements and fixes. The main core part is
  reworking bio handling, cleaning up the submission and endio and
  improving error handling.

  There are some changes outside of btrfs adding helpers or updating
  API, listed at the end of the changelog.

  Features:

   - sysfs:
      - export chunk size, in debug mode add tunable for setting its size
      - show zoned among features (was only in debug mode)
      - show commit stats (number, last/max/total duration)

   - send protocol updated to 2
      - new commands:
         - ability write larger data chunks than 64K
         - send raw compressed extents (uses the encoded data ioctls),
           ie. no decompression on send side, no compression needed on
           receive side if supported
         - send 'otime' (inode creation time) among other timestamps
         - send file attributes (a.k.a file flags and xflags)
      - this is first version bump, backward compatibility on send and
        receive side is provided
      - there are still some known and wanted commands that will be
        implemented in the near future, another version bump will be
        needed, however we want to minimize that to avoid causing
        usability issues

   - print checksum type and implementation at mount time

   - don't print some messages at mount (mentioned as people asked about
     it), we want to print messages namely for new features so let's
     make some space for that
      - big metadata - this has been supported for a long time and is
        not a feature that's worth mentioning
      - skinny metadata - same reason, set by default by mkfs

  Performance improvements:

   - reduced amount of reserved metadata for delayed items
      - when inserted items can be batched into one leaf
      - when deleting batched directory index items
      - when deleting delayed items used for deletion
      - overall improved count of files/sec, decreased subvolume lock
        contention

   - metadata item access bounds checker micro-optimized, with a few
     percent of improved runtime for metadata-heavy operations

   - increase direct io limit for read to 256 sectors, improved
     throughput by 3x on sample workload

  Notable fixes:

   - raid56
      - reduce parity writes, skip sectors of stripe when there are no
        data updates
      - restore reading from on-disk data instead of using stripe cache,
        this reduces chances to damage correct data due to RMW cycle

   - refuse to replay log with unknown incompat read-only feature bit
     set

   - zoned
      - fix page locking when COW fails in the middle of allocation
      - improved tracking of active zones, ZNS drives may limit the
        number and there are ENOSPC errors due to that limit and not
        actual lack of space
      - adjust maximum extent size for zone append so it does not cause
        late ENOSPC due to underreservation

   - mirror reading error messages show the mirror number

   - don't fallback to buffered IO for NOWAIT direct IO writes, we don't
     have the NOWAIT semantics for buffered io yet

   - send, fix sending link commands for existing file paths when there
     are deleted and created hardlinks for same files

   - repair all mirrors for profiles with more than 1 copy (raid1c34)

   - fix repair of compressed extents, unify where error detection and
     repair happen

  Core changes:

   - bio completion cleanups
      - don't double defer compression bios
      - simplify endio workqueues
      - add more data to btrfs_bio to avoid allocation for read requests
      - rework bio error handling so it's same what block layer does,
        the submission works and errors are consumed in endio
      - when asynchronous bio offload fails fall back to synchronous
        checksum calculation to avoid errors under writeback or memory
        pressure

   - new trace points
      - raid56 events
      - ordered extent operations

   - super block log_root_transid deprecated (never used)

   - mixed_backref and big_metadata sysfs feature files removed, they've
     been default for sufficiently long time, there are no known users
     and mixed_backref could be confused with mixed_groups

  Non-btrfs changes, API updates:

   - minor highmem API update to cover const arguments

   - switch all kmap/kmap_atomic to kmap_local

   - remove redundant flush_dcache_page()

   - address_space_operations::writepage callback removed

   - add bdev_max_segments() helper"

* tag 'for-5.20-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: (163 commits)
  btrfs: don't call btrfs_page_set_checked in finish_compressed_bio_read
  btrfs: fix repair of compressed extents
  btrfs: remove the start argument to check_data_csum and export
  btrfs: pass a btrfs_bio to btrfs_repair_one_sector
  btrfs: simplify the pending I/O counting in struct compressed_bio
  btrfs: repair all known bad mirrors
  btrfs: merge btrfs_dev_stat_print_on_error with its only caller
  btrfs: join running log transaction when logging new name
  btrfs: simplify error handling in btrfs_lookup_dentry
  btrfs: send: always use the rbtree based inode ref management infrastructure
  btrfs: send: fix sending link commands for existing file paths
  btrfs: send: introduce recorded_ref_alloc and recorded_ref_free
  btrfs: zoned: wait until zone is finished when allocation didn't progress
  btrfs: zoned: write out partially allocated region
  btrfs: zoned: activate necessary block group
  btrfs: zoned: activate metadata block group on flush_space
  btrfs: zoned: disable metadata overcommit for zoned
  btrfs: zoned: introduce space_info->active_total_bytes
  btrfs: zoned: finish least available block group on data bg allocation
  btrfs: let can_allocate_chunk return error
  ...
2022-08-03 14:54:52 -07:00
Linus Torvalds
5264406cdb iov_iter work, part 1 - isolated cleanups and optimizations.
One of the goals is to reduce the overhead of using ->read_iter()
 and ->write_iter() instead of ->read()/->write(); new_sync_{read,write}()
 has a surprising amount of overhead, in particular inside iocb_flags().
 That's why the beginning of the series is in this pile; it's not directly
 iov_iter-related, but it's a part of the same work...
 
 Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
 -----BEGIN PGP SIGNATURE-----
 
 iHUEABYIAB0WIQQqUNBr3gm4hGXdBJlZ7Krx/gZQ6wUCYurGOQAKCRBZ7Krx/gZQ
 6ysyAP91lvBfMRepcxpd9kvtuzWkU8A3rfSziZZteEHANB9Q7QEAiPn2a2OjWkcZ
 uAyUWfCkHCNx+dSMkEvUgR5okQ0exAM=
 =9UCV
 -----END PGP SIGNATURE-----

Merge tag 'pull-work.iov_iter-base' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull vfs iov_iter updates from Al Viro:
 "Part 1 - isolated cleanups and optimizations.

  One of the goals is to reduce the overhead of using ->read_iter() and
  ->write_iter() instead of ->read()/->write().

  new_sync_{read,write}() has a surprising amount of overhead, in
  particular inside iocb_flags(). That's the explanation for the
  beginning of the series is in this pile; it's not directly
  iov_iter-related, but it's a part of the same work..."

* tag 'pull-work.iov_iter-base' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  first_iovec_segment(): just return address
  iov_iter: massage calling conventions for first_{iovec,bvec}_segment()
  iov_iter: first_{iovec,bvec}_segment() - simplify a bit
  iov_iter: lift dealing with maxpages out of first_{iovec,bvec}_segment()
  iov_iter_get_pages{,_alloc}(): cap the maxsize with MAX_RW_COUNT
  iov_iter_bvec_advance(): don't bother with bvec_iter
  copy_page_{to,from}_iter(): switch iovec variants to generic
  keep iocb_flags() result cached in struct file
  iocb: delay evaluation of IS_SYNC(...) until we want to check IOCB_DSYNC
  struct file: use anonymous union member for rcuhead and llist
  btrfs: use IOMAP_DIO_NOSYNC
  teach iomap_dio_rw() to suppress dsync
  No need of likely/unlikely on calls of check_copy_size()
2022-08-03 13:50:22 -07:00
Linus Torvalds
f00654007f Folio changes for 6.0
- Fix an accounting bug that made NR_FILE_DIRTY grow without limit
    when running xfstests
 
  - Convert more of mpage to use folios
 
  - Remove add_to_page_cache() and add_to_page_cache_locked()
 
  - Convert find_get_pages_range() to filemap_get_folios()
 
  - Improvements to the read_cache_page() family of functions
 
  - Remove a few unnecessary checks of PageError
 
  - Some straightforward filesystem conversions to use folios
 
  - Split PageMovable users out from address_space_operations into their
    own movable_operations
 
  - Convert aops->migratepage to aops->migrate_folio
 
  - Remove nobh support (Christoph Hellwig)
 -----BEGIN PGP SIGNATURE-----
 
 iQEzBAABCgAdFiEEejHryeLBw/spnjHrDpNsjXcpgj4FAmLpViQACgkQDpNsjXcp
 gj5pBgf/f3+K7Hi3qw7aYQCYJQ7IA/bLyE/DLWI59kuiao6wDSve40B9YH9X++Ha
 mRLp55bkQS+bwS2xa4jlqrIDJzAfNoWlXaXZHUXGL1C/52ChTF6jaH2cvO9PVlDS
 7fLv1hy2LwiIdzpKJkUW7T+kcQGj3QLKqtQ4x8zD0LGMg055yvt/qndHSUi41nWT
 /58+6W8Sk4vvRgkpeChFzF1lGLy00+FGT8y5V2kM9uRliFQ7XPCwqB2a3e5jbW6z
 C1NXQmRnopCrnOT1TFIhK3DyX6MDIWV5qcikNAmCKFb9fQFPmjDLPt9iSoMGjw2M
 Z+UVhJCaU3ISccd0DG5Ra/vzs9/O9Q==
 =DgUi
 -----END PGP SIGNATURE-----

Merge tag 'folio-6.0' of git://git.infradead.org/users/willy/pagecache

Pull folio updates from Matthew Wilcox:

 - Fix an accounting bug that made NR_FILE_DIRTY grow without limit
   when running xfstests

 - Convert more of mpage to use folios

 - Remove add_to_page_cache() and add_to_page_cache_locked()

 - Convert find_get_pages_range() to filemap_get_folios()

 - Improvements to the read_cache_page() family of functions

 - Remove a few unnecessary checks of PageError

 - Some straightforward filesystem conversions to use folios

 - Split PageMovable users out from address_space_operations into
   their own movable_operations

 - Convert aops->migratepage to aops->migrate_folio

 - Remove nobh support (Christoph Hellwig)

* tag 'folio-6.0' of git://git.infradead.org/users/willy/pagecache: (78 commits)
  fs: remove the NULL get_block case in mpage_writepages
  fs: don't call ->writepage from __mpage_writepage
  fs: remove the nobh helpers
  jfs: stop using the nobh helper
  ext2: remove nobh support
  ntfs3: refactor ntfs_writepages
  mm/folio-compat: Remove migration compatibility functions
  fs: Remove aops->migratepage()
  secretmem: Convert to migrate_folio
  hugetlb: Convert to migrate_folio
  aio: Convert to migrate_folio
  f2fs: Convert to filemap_migrate_folio()
  ubifs: Convert to filemap_migrate_folio()
  btrfs: Convert btrfs_migratepage to migrate_folio
  mm/migrate: Add filemap_migrate_folio()
  mm/migrate: Convert migrate_page() to migrate_folio()
  nfs: Convert to migrate_folio
  btrfs: Convert btree_migratepage to migrate_folio
  mm/migrate: Convert expected_page_refs() to folio_expected_refs()
  mm/migrate: Convert buffer_migrate_page() to buffer_migrate_folio()
  ...
2022-08-03 10:35:43 -07:00
Linus Torvalds
c013d0af81 for-5.20/block-2022-07-29
-----BEGIN PGP SIGNATURE-----
 
 iQJEBAABCAAuFiEEwPw5LcreJtl1+l5K99NY+ylx4KYFAmLko3gQHGF4Ym9lQGtl
 cm5lbC5kawAKCRD301j7KXHgpmQaD/90NKFj4v8I456TUQyg1jimXEsL+e84E6o2
 ALWVb6JzQvlPVQXNLnK5YKIunMWOTtTMz0nyB8sVRwVJVJO0P5d7QopAkZM8fkyU
 MK5OCzoryENw4DTc2wJS4in6cSbGylIuN74wMzlf7+M67JTImfoZQhbTMcjwzZfn
 b3OlL6sID7zMXwGcuOJPZyUJICCpDhzdSF9JXqKma5PQuG2SBmQyvFxJAcsoFBPc
 YetnoRIOIN6yBvsIZaPaYq7XI9MIvF0e67EQtyCEHj4tHpyVnyDWkeObVFULsISU
 gGEKbkYPvNUzRAU5Q1NBBHh1tTfkf/MaUxTuZwoEwZ/s04IGBGMmrZGyfvdfzYo6
 M7NwSEg/TrUSNfTwn65mQi7uOXu1pGkJrqz84Flm8u9Qid9Vd7LExLG5p/ggnWdH
 5th93MDEmtEg29e9DXpEAuS5d0t3TtSvosflaKpyfNNfr+P0rWCN6GM/uW62VUTK
 ls69SQh/AQJRbg64jU4xper6WhaYtSXK7TKEnxJycoEn9gYNyCcdot2uekth0xRH
 ChHGmRlteiqe/y4uFWn/2dcxWjoleiHbFjTaiRL75WVl8wIDEjw02LGuoZ61Ss9H
 WOV+MT7KqNjBGe6lreUY+O/PO02dzmoR6heJXN19p8zr/pBuLCTGX7UpO7rzgaBR
 4N1HEozvIw==
 =celk
 -----END PGP SIGNATURE-----

Merge tag 'for-5.20/block-2022-07-29' of git://git.kernel.dk/linux-block

Pull block updates from Jens Axboe:

 - Improve the type checking of request flags (Bart)

 - Ensure queue mapping for a single queues always picks the right queue
   (Bart)

 - Sanitize the io priority handling (Jan)

 - rq-qos race fix (Jinke)

 - Reserved tags handling improvements (John)

 - Separate memory alignment from file/disk offset aligment for O_DIRECT
   (Keith)

 - Add new ublk driver, userspace block driver using io_uring for
   communication with the userspace backend (Ming)

 - Use try_cmpxchg() to cleanup the code in various spots (Uros)

 - Finally remove bdevname() (Christoph)

 - Clean up the zoned device handling (Christoph)

 - Clean up independent access range support (Christoph)

 - Clean up and improve block sysfs handling (Christoph)

 - Clean up and improve teardown of block devices.

   This turns the usual two step process into something that is simpler
   to implement and handle in block drivers (Christoph)

 - Clean up chunk size handling (Christoph)

 - Misc cleanups and fixes (Bart, Bo, Dan, GuoYong, Jason, Keith, Liu,
   Ming, Sebastian, Yang, Ying)

* tag 'for-5.20/block-2022-07-29' of git://git.kernel.dk/linux-block: (178 commits)
  ublk_drv: fix double shift bug
  ublk_drv: make sure that correct flags(features) returned to userspace
  ublk_drv: fix error handling of ublk_add_dev
  ublk_drv: fix lockdep warning
  block: remove __blk_get_queue
  block: call blk_mq_exit_queue from disk_release for never added disks
  blk-mq: fix error handling in __blk_mq_alloc_disk
  ublk: defer disk allocation
  ublk: rewrite ublk_ctrl_get_queue_affinity to not rely on hctx->cpumask
  ublk: fold __ublk_create_dev into ublk_ctrl_add_dev
  ublk: cleanup ublk_ctrl_uring_cmd
  ublk: simplify ublk_ch_open and ublk_ch_release
  ublk: remove the empty open and release block device operations
  ublk: remove UBLK_IO_F_PREFLUSH
  ublk: add a MAINTAINERS entry
  block: don't allow the same type rq_qos add more than once
  mmc: fix disk/queue leak in case of adding disk failure
  ublk_drv: fix an IS_ERR() vs NULL check
  ublk: remove UBLK_IO_F_INTEGRITY
  ublk_drv: remove unneeded semicolon
  ...
2022-08-02 13:46:35 -07:00
Matthew Wilcox (Oracle)
e7a60a1787 btrfs: Convert btrfs_migratepage to migrate_folio
Use filemap_migrate_folio() to do the bulk of the work, and then copy
the ordered flag across if needed.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: David Sterba <dsterba@suse.com>
2022-08-02 12:34:04 -04:00
Christoph Hellwig
0b078d9db8 btrfs: don't call btrfs_page_set_checked in finish_compressed_bio_read
This flag was used to communicate that the low-level compression code
already did verify the checksum to the high-level I/O completion code.

But it has been unused for a long time as the upper btrfs_bio for the
decompressed data had a NULL csum pointer basically since that pointer
existed and the code already checks for that a little later.

Note that this does not affect the other use of the checked flag, which
is only used for the COW fixup worker.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 19:56:16 +02:00
Christoph Hellwig
81bd9328ab btrfs: fix repair of compressed extents
Currently the checksum of compressed extents is verified based on the
compressed data and the lower btrfs_bio, but the actual repair process
is driven by end_bio_extent_readpage on the upper btrfs_bio for the
decompressed data.

This has a bunch of issues, including not being able to properly
communicate the failed mirror up in case that the I/O submission got
preempted, a general loss of if an error was an I/O error or a checksum
verification failure, but most importantly that this design causes
btrfs_clean_io_failure to eventually write back the uncompressed good
data onto the disk sectors that are supposed to contain compressed data.

Fix this by moving the repair to the lower btrfs_bio.  To do so, a fair
amount of code has to be reshuffled:

 a) the lower btrfs_bio now needs a valid csum pointer.  The easiest way
    to achieve that is to pass NULL btrfs_lookup_bio_sums and just use
    the btrfs_bio management of csums.  For a compressed_bio that is
    split into multiple btrfs_bios this means additional memory
    allocations, but the code becomes a lot more regular.
 b) checksum verification now runs directly on the lower btrfs_bio instead
    of the compressed_bio.  This actually nicely simplifies the end I/O
    processing.
 c) btrfs_repair_one_sector can't just look up the logical address for
    the file offset any more, as there is no corresponding relative
    offsets that apply to the file offset and the logic address for
    compressed extents.  Instead require that the saved bvec_iter in the
    btrfs_bio is filled out for all read bios and use that, which again
    removes a fair amount of code.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 19:56:16 +02:00
Christoph Hellwig
7959bd4411 btrfs: remove the start argument to check_data_csum and export
Derive the value of start from the btrfs_bio now that ->file_offset is
always valid.  Also export and rename the function so it's available
outside of inode.c as we'll need that soon.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Boris Burkov <boris@bur.io>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 19:55:32 +02:00
Christoph Hellwig
7aa51232e2 btrfs: pass a btrfs_bio to btrfs_repair_one_sector
Pass the btrfs_bio instead of the plain bio to btrfs_repair_one_sector,
and remove the start and failed_mirror arguments in favor of deriving
them from the btrfs_bio.  For this to work ensure that the file_offset
field is also initialized for buffered I/O.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Boris Burkov <boris@bur.io>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 19:55:19 +02:00
Nikolay Borisov
fc8b235fdc btrfs: simplify error handling in btrfs_lookup_dentry
In btrfs_lookup_dentry releasing the reference of the sub_root and the
running orphan cleanup should only happen if the dentry found actually
represents a subvolume. This can only be true in the 'else' branch as
otherwise either fixup_tree_root_location returned an ENOENT error, in
which case sub_root wouldn't have been changed or if we got a different
errno this means btrfs_get_fs_root couldn't have executed successfully
again meaning sub_root will equal to root. So simplify all the branches
by moving the code into the 'else'.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 17:45:42 +02:00
Naohiro Aota
2ce543f478 btrfs: zoned: wait until zone is finished when allocation didn't progress
When the allocated position doesn't progress, we cannot submit IOs to
finish a block group, but there should be ongoing IOs that will finish a
block group. So, in that case, we wait for a zone to be finished and retry
the allocation after that.

Introduce a new flag BTRFS_FS_NEED_ZONE_FINISH for fs_info->flags to
indicate we need a zone finish to have proceeded. The flag is set when the
allocator detected it cannot activate a new block group. And, it is cleared
once a zone is finished.

CC: stable@vger.kernel.org # 5.16+
Fixes: afba2bc036 ("btrfs: zoned: implement active zone tracking")
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 17:45:42 +02:00
Naohiro Aota
898793d992 btrfs: zoned: write out partially allocated region
cow_file_range() works in an all-or-nothing way: if it fails to allocate an
extent for a part of the given region, it gives up all the region including
the successfully allocated parts. On cow_file_range(), run_delalloc_zoned()
writes data for the region only when it successfully allocate all the
region.

This all-or-nothing allocation and write-out are problematic when available
space in all the block groups are get tight with the active zone
restriction. btrfs_reserve_extent() try hard to utilize the left space in
the active block groups and gives up finally and fails with
-ENOSPC. However, if we send IOs for the successfully allocated region, we
can finish a zone and can continue on the rest of the allocation on a newly
allocated block group.

This patch implements the partial write-out for run_delalloc_zoned(). With
this patch applied, cow_file_range() returns -EAGAIN to tell the caller to
do something to progress the further allocation, and tells the successfully
allocated region with done_offset. Furthermore, the zoned extent allocator
returns -EAGAIN to tell cow_file_range() going back to the caller side.

Actually, we still need to wait for an IO to complete to continue the
allocation. The next patch implements that part.

CC: stable@vger.kernel.org # 5.16+
Fixes: afba2bc036 ("btrfs: zoned: implement active zone tracking")
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 17:45:42 +02:00
Naohiro Aota
7d7672bc5d btrfs: convert count_max_extents() to use fs_info->max_extent_size
If count_max_extents() uses BTRFS_MAX_EXTENT_SIZE to calculate the number
of extents needed, btrfs release the metadata reservation too much on its
way to write out the data.

Now that BTRFS_MAX_EXTENT_SIZE is replaced with fs_info->max_extent_size,
convert count_max_extents() to use it instead, and fix the calculation of
the metadata reservation.

CC: stable@vger.kernel.org # 5.12+
Fixes: d8e3fb106f ("btrfs: zoned: use ZONE_APPEND write for zoned mode")
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 17:45:41 +02:00
Naohiro Aota
f7b12a62f0 btrfs: replace BTRFS_MAX_EXTENT_SIZE with fs_info->max_extent_size
On zoned filesystem, data write out is limited by max_zone_append_size,
and a large ordered extent is split according the size of a bio. OTOH,
the number of extents to be written is calculated using
BTRFS_MAX_EXTENT_SIZE, and that estimated number is used to reserve the
metadata bytes to update and/or create the metadata items.

The metadata reservation is done at e.g, btrfs_buffered_write() and then
released according to the estimation changes. Thus, if the number of extent
increases massively, the reserved metadata can run out.

The increase of the number of extents easily occurs on zoned filesystem
if BTRFS_MAX_EXTENT_SIZE > max_zone_append_size. And, it causes the
following warning on a small RAM environment with disabling metadata
over-commit (in the following patch).

[75721.498492] ------------[ cut here ]------------
[75721.505624] BTRFS: block rsv 1 returned -28
[75721.512230] WARNING: CPU: 24 PID: 2327559 at fs/btrfs/block-rsv.c:537 btrfs_use_block_rsv+0x560/0x760 [btrfs]
[75721.581854] CPU: 24 PID: 2327559 Comm: kworker/u64:10 Kdump: loaded Tainted: G        W         5.18.0-rc2-BTRFS-ZNS+ #109
[75721.597200] Hardware name: Supermicro Super Server/H12SSL-NT, BIOS 2.0 02/22/2021
[75721.607310] Workqueue: btrfs-endio-write btrfs_work_helper [btrfs]
[75721.616209] RIP: 0010:btrfs_use_block_rsv+0x560/0x760 [btrfs]
[75721.646649] RSP: 0018:ffffc9000fbdf3e0 EFLAGS: 00010286
[75721.654126] RAX: 0000000000000000 RBX: 0000000000004000 RCX: 0000000000000000
[75721.663524] RDX: 0000000000000004 RSI: 0000000000000008 RDI: fffff52001f7be6e
[75721.672921] RBP: ffffc9000fbdf420 R08: 0000000000000001 R09: ffff889f8d1fc6c7
[75721.682493] R10: ffffed13f1a3f8d8 R11: 0000000000000001 R12: ffff88980a3c0e28
[75721.692284] R13: ffff889b66590000 R14: ffff88980a3c0e40 R15: ffff88980a3c0e8a
[75721.701878] FS:  0000000000000000(0000) GS:ffff889f8d000000(0000) knlGS:0000000000000000
[75721.712601] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[75721.720726] CR2: 000055d12e05c018 CR3: 0000800193594000 CR4: 0000000000350ee0
[75721.730499] Call Trace:
[75721.735166]  <TASK>
[75721.739886]  btrfs_alloc_tree_block+0x1e1/0x1100 [btrfs]
[75721.747545]  ? btrfs_alloc_logged_file_extent+0x550/0x550 [btrfs]
[75721.756145]  ? btrfs_get_32+0xea/0x2d0 [btrfs]
[75721.762852]  ? btrfs_get_32+0xea/0x2d0 [btrfs]
[75721.769520]  ? push_leaf_left+0x420/0x620 [btrfs]
[75721.776431]  ? memcpy+0x4e/0x60
[75721.781931]  split_leaf+0x433/0x12d0 [btrfs]
[75721.788392]  ? btrfs_get_token_32+0x580/0x580 [btrfs]
[75721.795636]  ? push_for_double_split.isra.0+0x420/0x420 [btrfs]
[75721.803759]  ? leaf_space_used+0x15d/0x1a0 [btrfs]
[75721.811156]  btrfs_search_slot+0x1bc3/0x2790 [btrfs]
[75721.818300]  ? lock_downgrade+0x7c0/0x7c0
[75721.824411]  ? free_extent_buffer.part.0+0x107/0x200 [btrfs]
[75721.832456]  ? split_leaf+0x12d0/0x12d0 [btrfs]
[75721.839149]  ? free_extent_buffer.part.0+0x14f/0x200 [btrfs]
[75721.846945]  ? free_extent_buffer+0x13/0x20 [btrfs]
[75721.853960]  ? btrfs_release_path+0x4b/0x190 [btrfs]
[75721.861429]  btrfs_csum_file_blocks+0x85c/0x1500 [btrfs]
[75721.869313]  ? rcu_read_lock_sched_held+0x16/0x80
[75721.876085]  ? lock_release+0x552/0xf80
[75721.881957]  ? btrfs_del_csums+0x8c0/0x8c0 [btrfs]
[75721.888886]  ? __kasan_check_write+0x14/0x20
[75721.895152]  ? do_raw_read_unlock+0x44/0x80
[75721.901323]  ? _raw_write_lock_irq+0x60/0x80
[75721.907983]  ? btrfs_global_root+0xb9/0xe0 [btrfs]
[75721.915166]  ? btrfs_csum_root+0x12b/0x180 [btrfs]
[75721.921918]  ? btrfs_get_global_root+0x820/0x820 [btrfs]
[75721.929166]  ? _raw_write_unlock+0x23/0x40
[75721.935116]  ? unpin_extent_cache+0x1e3/0x390 [btrfs]
[75721.942041]  btrfs_finish_ordered_io.isra.0+0xa0c/0x1dc0 [btrfs]
[75721.949906]  ? try_to_wake_up+0x30/0x14a0
[75721.955700]  ? btrfs_unlink_subvol+0xda0/0xda0 [btrfs]
[75721.962661]  ? rcu_read_lock_sched_held+0x16/0x80
[75721.969111]  ? lock_acquire+0x41b/0x4c0
[75721.974982]  finish_ordered_fn+0x15/0x20 [btrfs]
[75721.981639]  btrfs_work_helper+0x1af/0xa80 [btrfs]
[75721.988184]  ? _raw_spin_unlock_irq+0x28/0x50
[75721.994643]  process_one_work+0x815/0x1460
[75722.000444]  ? pwq_dec_nr_in_flight+0x250/0x250
[75722.006643]  ? do_raw_spin_trylock+0xbb/0x190
[75722.013086]  worker_thread+0x59a/0xeb0
[75722.018511]  kthread+0x2ac/0x360
[75722.023428]  ? process_one_work+0x1460/0x1460
[75722.029431]  ? kthread_complete_and_exit+0x30/0x30
[75722.036044]  ret_from_fork+0x22/0x30
[75722.041255]  </TASK>
[75722.045047] irq event stamp: 0
[75722.049703] hardirqs last  enabled at (0): [<0000000000000000>] 0x0
[75722.057610] hardirqs last disabled at (0): [<ffffffff8118a94a>] copy_process+0x1c1a/0x66b0
[75722.067533] softirqs last  enabled at (0): [<ffffffff8118a989>] copy_process+0x1c59/0x66b0
[75722.077423] softirqs last disabled at (0): [<0000000000000000>] 0x0
[75722.085335] ---[ end trace 0000000000000000 ]---

To fix the estimation, we need to introduce fs_info->max_extent_size to
replace BTRFS_MAX_EXTENT_SIZE, which allow setting the different size for
regular vs zoned filesystem.

Set fs_info->max_extent_size to BTRFS_MAX_EXTENT_SIZE by default. On zoned
filesystem, it is set to fs_info->max_zone_append_size.

CC: stable@vger.kernel.org # 5.12+
Fixes: d8e3fb106f ("btrfs: zoned: use ZONE_APPEND write for zoned mode")
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 17:45:41 +02:00
Fabio M. De Francesco
4cb2e5e8fe btrfs: replace kmap_atomic() with kmap_local_page()
kmap_atomic() is being deprecated in favor of kmap_local_page() where it
is feasible. With kmap_local_page() mappings are per thread, CPU local,
and not globally visible.

The last use of kmap_atomic is in inode.c where the context is atomic [1]
and can be safely replaced by kmap_local_page.

Tested with xfstests on a QEMU + KVM 32-bits VM with 4GB RAM and booting a
kernel with HIGHMEM64GB enabled.

[1] https://lore.kernel.org/linux-btrfs/20220601132545.GM20633@twin.jikos.cz/

Suggested-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 17:45:41 +02:00
David Sterba
710d5921d1 btrfs: switch btrfs_block_rsv::failfast to bool
Use simple bool type for the block reserve failfast status, there's
short to save space as there used to be int but there's no reason for
that.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 17:45:40 +02:00
Christoph Hellwig
37899117e8 btrfs: do not return errors from btrfs_submit_dio_bio
Always consume the bio and call the end_io handler on error instead of
returning an error and letting the caller handle it.  This matches what
the block layer submission and the other btrfs bio submission handlers do
and avoids any confusion on who needs to handle errors.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Tested-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 17:45:40 +02:00
Christoph Hellwig
ea1f0cedef btrfs: handle allocation failure in btrfs_wq_submit_bio gracefully
btrfs_wq_submit_bio is used for writeback under memory pressure.
Instead of failing the I/O when we can't allocate the async_submit_bio,
just punt back to the synchronous submission path.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Tested-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 17:45:40 +02:00
Christoph Hellwig
82443fd55c btrfs: simplify sync/async submission in btrfs_submit_data_write_bio
btrfs_submit_data_write_bio special cases the reloc root because the
checksums are preloaded, but only does so for the !sync case.  The sync
case can't happen for data relocation, but just handling it more generally
significantly simplifies the logic.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Tested-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 17:45:40 +02:00
Christoph Hellwig
1a722d8f5b btrfs: do not return errors from btrfs_map_bio
Always consume the bio and call the end_io handler on error instead of
returning an error and letting the caller handle it.  This matches
what the block layer submission does and avoids any confusion on who
needs to handle errors.

As this requires touching all the callers, rename the function to
btrfs_submit_bio, which describes the functionality much better.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Tested-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 17:45:39 +02:00
David Sterba
c1867eb33e btrfs: clean up chained assignments
The chained assignments may be convenient to write, but make readability
a bit worse as it's too easy to overlook that there are several values
set on the same line while this is rather an exception.  Making it
consistent everywhere avoids surprises.

The pattern where inode times are initialized reuses the first value and
the order is mtime, ctime. In other blocks the assignments are expanded
so the order of variables is similar to the neighboring code.

Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 17:45:39 +02:00
Naohiro Aota
aaafa1ebd6 btrfs: replace unnecessary goto with direct return at cow_file_range()
The 'goto out' in cow_file_range() in the exit block are not necessary
and jump back. Replace them with return, while still keeping 'goto out'
in the main code.

Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ keep goto in the main code, update changelog ]
Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 17:45:38 +02:00
Naohiro Aota
71aa147b4d btrfs: fix error handling of fallback uncompress write
When cow_file_range() fails in the middle of the allocation loop, it
unlocks the pages but leaves the ordered extents intact. Thus, we need
to call btrfs_cleanup_ordered_extents() to finish the created ordered
extents.

Also, we need to call end_extent_writepage() if locked_page is available
because btrfs_cleanup_ordered_extents() never processes the region on
the locked_page.

Furthermore, we need to set the mapping as error if locked_page is
unavailable before unlocking the pages, so that the errno is properly
propagated to the user space.

CC: stable@vger.kernel.org # 5.18+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 17:45:38 +02:00
Naohiro Aota
99826e4cab btrfs: extend btrfs_cleanup_ordered_extents for NULL locked_page
btrfs_cleanup_ordered_extents() assumes locked_page to be non-NULL, so it
is not usable for submit_uncompressed_range() which can have NULL
locked_page.

Add support supports locked_page == NULL case. Also, it rewrites
redundant "page_offset(locked_page)".

Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 17:45:38 +02:00
Naohiro Aota
9ce7466f37 btrfs: ensure pages are unlocked on cow_file_range() failure
There is a hung_task report on zoned btrfs like below.

https://github.com/naota/linux/issues/59

  [726.328648] INFO: task rocksdb:high0:11085 blocked for more than 241 seconds.
  [726.329839]       Not tainted 5.16.0-rc1+ #1
  [726.330484] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
  [726.331603] task:rocksdb:high0   state:D stack:    0 pid:11085 ppid: 11082 flags:0x00000000
  [726.331608] Call Trace:
  [726.331611]  <TASK>
  [726.331614]  __schedule+0x2e5/0x9d0
  [726.331622]  schedule+0x58/0xd0
  [726.331626]  io_schedule+0x3f/0x70
  [726.331629]  __folio_lock+0x125/0x200
  [726.331634]  ? find_get_entries+0x1bc/0x240
  [726.331638]  ? filemap_invalidate_unlock_two+0x40/0x40
  [726.331642]  truncate_inode_pages_range+0x5b2/0x770
  [726.331649]  truncate_inode_pages_final+0x44/0x50
  [726.331653]  btrfs_evict_inode+0x67/0x480
  [726.331658]  evict+0xd0/0x180
  [726.331661]  iput+0x13f/0x200
  [726.331664]  do_unlinkat+0x1c0/0x2b0
  [726.331668]  __x64_sys_unlink+0x23/0x30
  [726.331670]  do_syscall_64+0x3b/0xc0
  [726.331674]  entry_SYSCALL_64_after_hwframe+0x44/0xae
  [726.331677] RIP: 0033:0x7fb9490a171b
  [726.331681] RSP: 002b:00007fb943ffac68 EFLAGS: 00000246 ORIG_RAX: 0000000000000057
  [726.331684] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fb9490a171b
  [726.331686] RDX: 00007fb943ffb040 RSI: 000055a6bbe6ec20 RDI: 00007fb94400d300
  [726.331687] RBP: 00007fb943ffad00 R08: 0000000000000000 R09: 0000000000000000
  [726.331688] R10: 0000000000000031 R11: 0000000000000246 R12: 00007fb943ffb000
  [726.331690] R13: 00007fb943ffb040 R14: 0000000000000000 R15: 00007fb943ffd260
  [726.331693]  </TASK>

While we debug the issue, we found running fstests generic/551 on 5GB
non-zoned null_blk device in the emulated zoned mode also had a
similar hung issue.

Also, we can reproduce the same symptom with an error injected
cow_file_range() setup.

The hang occurs when cow_file_range() fails in the middle of
allocation. cow_file_range() called from do_allocation_zoned() can
split the give region ([start, end]) for allocation depending on
current block group usages. When btrfs can allocate bytes for one part
of the split regions but fails for the other region (e.g. because of
-ENOSPC), we return the error leaving the pages in the succeeded regions
locked. Technically, this occurs only when @unlock == 0. Otherwise, we
unlock the pages in an allocated region after creating an ordered
extent.

Considering the callers of cow_file_range(unlock=0) won't write out
the pages, we can unlock the pages on error exit from
cow_file_range(). So, we can ensure all the pages except @locked_page
are unlocked on error case.

In summary, cow_file_range now behaves like this:

- page_started == 1 (return value)
  - All the pages are unlocked. IO is started.
- unlock == 1
  - All the pages except @locked_page are unlocked in any case
- unlock == 0
  - On success, all the pages are locked for writing out them
  - On failure, all the pages except @locked_page are unlocked

Fixes: 42c0110009 ("btrfs: zoned: introduce dedicated data write path for zoned filesystems")
CC: stable@vger.kernel.org # 5.12+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 17:45:38 +02:00
Christoph Hellwig
f3e90c1ca9 btrfs: remove extent writepage address space operation
Same as in commit 21b4ee7029 ("xfs: drop ->writepage completely"): we
can remove the callback as it's only used in one place - single page
writeback from memory reclaim and is not called for cgroup writeback at
all.

We only allow such writeback from kswapd, not from direct memory
reclaim, and so it is rarely used. When it comes from kswapd, it is
effectively random dirty page shoot-down, which is horrible for IO
patterns. We can rely on background writeback to clean all dirty pages
in an efficient way and not let it be interrupted by kswapd.

Suggested-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 17:45:37 +02:00
Christoph Hellwig
ee5b46a353 btrfs: increase direct io read size limit to 256 sectors
Btrfs currently limits direct I/O reads to a single sector, which goes
back to commit c329861da4 ("Btrfs: don't allocate a separate csums
array for direct reads") from Josef.  That commit changes the direct I/O
code to ".. use the private part of the io_tree for our csums.", but ten
years later that isn't how checksums for direct reads work, instead they
use a csums allocation on a per-btrfs_dio_private basis (which have their
own performance problem for small I/O, but that will be addressed later).

There is no fundamental limit in btrfs itself to limit the I/O size
except for the size of the checksum array that scales linearly with
the number of sectors in an I/O.  Pick a somewhat arbitrary limit of
256 limits, which matches what the buffered reads typically see as
the upper limit as the limit for direct I/O as well.

This significantly improves direct read performance.  For example a fio
run doing 1 MiB aio reads with a queue depth of 1 roughly triples the
throughput:

Baseline:

READ: bw=65.3MiB/s (68.5MB/s), 65.3MiB/s-65.3MiB/s (68.5MB/s-68.5MB/s), io=19.1GiB (20.6GB), run=300013-300013msec

With this patch:

READ: bw=196MiB/s (206MB/s), 196MiB/s-196MiB/s (206MB/s-206MB/s), io=57.5GiB (61.7GB), run=300006-300006msc

Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 17:45:37 +02:00
Christoph Hellwig
711f447b4f btrfs: remove the finish_func argument to btrfs_mark_ordered_io_finished
finish_func is always set to finish_ordered_fn, so remove it and also
the now pointless and somewhat confusingly named
__endio_write_update_ordered wrapper.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 17:45:37 +02:00
David Sterba
6d92b304ec btrfs: pass bits by value not by pointer for extent_state helpers
The bits are passed to all extent state helpers for no apparent reason,
the value only read and never updated so remove the indirection and pass
it directly. Also unify the type to u32 where needed.

Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 17:45:35 +02:00
Fabio M. De Francesco
70826b6bd5 btrfs: replace kmap() with kmap_local_page() in inode.c
The use of kmap() is being deprecated in favor of kmap_local_page() where
it is feasible. With kmap_local_page(), the mapping is per thread, CPU
local and not globally visible.

Therefore, use kmap_local_page() / kunmap_local() in inode.c wherever the
mappings are per thread and not globally visible.

Tested on QEMU + KVM 32 bits VM with 4GB of RAM and HIGHMEM64G enabled.

Suggested-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 17:45:33 +02:00
Christoph Hellwig
d7b9416fe5 btrfs: remove btrfs_end_io_wq
All reads bio that go through btrfs_map_bio need to be completed in
user context.  And read I/Os are the most common and timing critical
in almost any file system workloads.

Embed a work_struct into struct btrfs_bio and use it to complete all
read bios submitted through btrfs_map, using the REQ_META flag to decide
which workqueue they are placed on.

This removes the need for a separate 128 byte allocation (typically
rounded up to 192 bytes by slab) for all reads with a size increase
of 24 bytes for struct btrfs_bio.  Future patches will reorganize
struct btrfs_bio to make use of this extra space for writes as well.

(All sizes are based a on typical 64-bit non-debug build)

Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 17:45:33 +02:00
Christoph Hellwig
02bb5b7247 btrfs: don't double-defer bio completions for compressed reads
The bio completion handler of the bio used for the compressed data is
already run in a workqueue using btrfs_bio_wq_end_io, so don't schedule
the completion of the original bio to the same workqueue again but just
execute it directly.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 17:45:33 +02:00
Christoph Hellwig
c93104e758 btrfs: split btrfs_submit_data_bio to read and write parts
Split btrfs_submit_data_bio into one helper for reads and one for writes.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 17:45:33 +02:00
Christoph Hellwig
e6484bd488 btrfs: simplify code flow in btrfs_submit_dio_bio
There is no exit block and cleanup and the function is reasonably short
so we can use inline return and not the goto. This makes the function
more straight forward.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 17:45:33 +02:00
Omar Sandoval
3ea4dc5bf0 btrfs: send: send compressed extents with encoded writes
Now that all of the pieces are in place, we can use the ENCODED_WRITE
command to send compressed extents when appropriate.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 17:45:32 +02:00
Filipe Manana
814e77182b btrfs: free the path earlier when creating a new inode
When creating an inode, through btrfs_create_new_inode(), we release the
path we allocated before once we don't need it anymore. But we keep it
allocated until we return from that function, which is wasteful because
after we release the path we do several things that can allocate yet
another path: inheriting properties, setting the xattrs used by ACLs and
secutiry modules, adding an orphan item (O_TMPFILE case) or adding a
dir item (for the non-O_TMPFILE case).

So instead of releasing the path once we don't need it anymore, free it
instead. This way we avoid having two paths allocated until we return
from btrfs_create_new_inode().

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 17:44:35 +02:00
Filipe Manana
ca6dee6b79 btrfs: balance btree dirty pages and delayed items after a rename
A rename operation modifies a subvolume's btree, to remove the old dir
item, add the new dir item, remove an inode ref and add a new inode ref.
It can also create the delayed inode for the inodes involved in the
operation, and it creates two delayed dir index items, one to delete
the old name and another one to add the new name.

However we are neither balancing the btree dirty pages nor the delayed
items after a rename, which can result in accumulation of too many
btree dirty pages and delayed items, specially if a task is doing a
series of rename operations (for example it can happen for package
installations/upgrades through the zypper tool).

So just call btrfs_btree_balance_dirty() after a rename, just like we
do for every other system call that results on modifying a btree and
adding delayed items.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 17:44:35 +02:00
David Sterba
21a8935ead btrfs: remove redundant calls to flush_dcache_page
Both memzero_page and memcpy_to_page already call flush_dcache_page so
we can remove the calls from btrfs code.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 17:44:34 +02:00
Christoph Hellwig
1e87770cb3 btrfs: use btrfs_bio_for_each_sector in btrfs_check_read_dio_bio
Use the new btrfs_bio_for_each_sector iterator to simplify
btrfs_check_read_dio_bio.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 17:44:34 +02:00
Christoph Hellwig
a89ce08ce6 btrfs: factor out a btrfs_csum_ptr helper
Add a helper to find the csum for a byte offset into the csum buffer.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 17:44:34 +02:00
Qu Wenruo
ae643a74eb btrfs: introduce a data checksum checking helper
Although we have several data csum verification code, we never have a
function really just to verify checksum for one sector.

Function check_data_csum() do extra work for error reporting, thus it
requires a lot of extra things like file offset, bio_offset etc.

Function btrfs_verify_data_csum() is even worse, it will utilize page
checked flag, which means it can not be utilized for direct IO pages.

Here we introduce a new helper, btrfs_check_sector_csum(), which really
only accept a sector in page, and expected checksum pointer.

We use this function to implement check_data_csum(), and export it for
incoming patch.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
[hch: keep passing the csum array as an arguments, as the callers want
      to print it, rename per request]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 17:44:33 +02:00
Fanjun Kong
1280d2d165 btrfs: use PAGE_ALIGNED instead of IS_ALIGNED
The <linux/mm.h> already provides the PAGE_ALIGNED macro. Let's
use it instead of IS_ALIGNED and passing PAGE_SIZE directly.

Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Fanjun Kong <bh1scw@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 17:44:33 +02:00
David Sterba
143823cf4d btrfs: fix typos in comments
Codespell has found a few typos.

Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-25 17:44:33 +02:00
Linus Torvalds
972a278fe6 for-5.19-rc7-tag
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEE8rQSAMVO+zA4DBdWxWXV+ddtWDsFAmLRpPgACgkQxWXV+ddt
 WDtu/BAAnfx7CXKIfWKpz6FZEio9Qb3mUHVOglyKzqR0qB72OdrC1dQMvEWPJc6h
 N65di6+8tTNmRIlaFBMU0MDHODR2aDRpDtlR9eUzUuidTc4iOp1fi31uBwl31r7b
 k8mCZBc/IAdfH13lBtcfkb2HGid7rik5ZC6Kx/glMcqh647QkSMAleupUsIYHKsK
 IgcUWuN3wFIUK2WVgsja7+ljlwIHBHKRp9yrEYw+ef/B0NCNKvOnrIOPJzO7nxMP
 1FbqJ6F7u7HjoMFcMwn5rbV/BoIwSSvXyKRqOW+EhGeQR/imVmkH9jXJ7wXdblSz
 IvSqaZ0DaWWSvivdMpwbr8Z0Cu4iIYhVY6PSA0hukR63qB5GwKKJ6j1L0zoYoz8C
 IDWJPW03FNRIu5ZOduvUQ3qG7jcJQZ3WPCCfrDST1cO2xHT/7f65Tjz4k0hvp4za
 edITetC1mEv310CHeGsJaLxGYPNrRe38VZYPxgJ7yFpteGYjh0ZwsuyUHb4MH1no
 JWwgElNW+m1BatdWSUBYk6xhqod1s2LOFPNqo7jNlv8I27hPViqCbBA2i9FlkXf+
 FwL5kWyJXs69gfjUIj59381Z0U1VdA1tvU8GP2m2+JvIDS6ooAcZj7yEQ69mCZxi
 2RFJIU0NFbnc/5j2ARSzOTGs9glDD0yffgXJM+cK+TWsQ3AC31I=
 =/47A
 -----END PGP SIGNATURE-----

Merge tag 'for-5.19-rc7-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs reverts from David Sterba:
 "Due to a recent report [1] we need to revert the radix tree to xarray
  conversion patches.

  There's a problem with sleeping under spinlock, when xa_insert could
  allocate memory under pressure. We use GFP_NOFS so this is a real
  problem that we unfortunately did not discover during review.

  I'm sorry to do such change at rc6 time but the revert is IMO the
  safer option, there are patches to use mutex instead of the spin locks
  but that would need more testing. The revert branch has been tested on
  a few setups, all seem ok.

  The conversion to xarray will be revisited in the future"

Link: https://lore.kernel.org/linux-btrfs/cover.1657097693.git.fdmanana@suse.com/ [1]

* tag 'for-5.19-rc7-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  Revert "btrfs: turn delayed_nodes_tree into an XArray"
  Revert "btrfs: turn name_cache radix tree into XArray in send_ctx"
  Revert "btrfs: turn fs_info member buffer_radix into XArray"
  Revert "btrfs: turn fs_roots_radix in btrfs_fs_info into an XArray"
2022-07-16 13:48:55 -07:00
David Sterba
088aea3b97 Revert "btrfs: turn delayed_nodes_tree into an XArray"
This reverts commit 253bf57555.

Revert the xarray conversion, there's a problem with potential
sleep-inside-spinlock [1] when calling xa_insert that triggers GFP_NOFS
allocation. The radix tree used the preloading mechanism to avoid
sleeping but this is not available in xarray.

Conversion from spin lock to mutex is possible but at time of rc6 is
riskier than a clean revert.

[1] https://lore.kernel.org/linux-btrfs/cover.1657097693.git.fdmanana@suse.com/

Reported-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-15 19:15:19 +02:00
David Sterba
fc7cbcd489 Revert "btrfs: turn fs_roots_radix in btrfs_fs_info into an XArray"
This reverts commit 48b36a602a.

Revert the xarray conversion, there's a problem with potential
sleep-inside-spinlock [1] when calling xa_insert that triggers GFP_NOFS
allocation. The radix tree used the preloading mechanism to avoid
sleeping but this is not available in xarray.

Conversion from spin lock to mutex is possible but at time of rc6 is
riskier than a clean revert.

[1] https://lore.kernel.org/linux-btrfs/cover.1657097693.git.fdmanana@suse.com/

Reported-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-15 19:14:28 +02:00
Bart Van Assche
bf9486d6dd fs/btrfs: Use the enum req_op and blk_opf_t types
Improve static type checking by using the enum req_op type for variables
that represent a request operation and the new blk_opf_t type for
variables that represent request flags.

Acked-by: David Sterba <dsterba@suse.com>
Cc: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20220714180729.1065367-51-bvanassche@acm.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-14 12:14:32 -06:00
Linus Torvalds
5a29232d87 for-5.19-rc6-tag
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEE8rQSAMVO+zA4DBdWxWXV+ddtWDsFAmLMiQQACgkQxWXV+ddt
 WDvBQg/+I1ebfW2DFY8kBwy7c1qKZWIhNx1VVk2AegIXvrW/Tos7wp5O6fi7p/jL
 d6k8zO/zFLlfiI4Ckmz3gt7cxaMTNXxr6+GQpNNm1b92Wdcy1a+3gquzcehT9Q10
 ZB4ecPWzEDXgORvdBYG2eD2Z8PrsF0Wu88XRDiiJOBQLjZ+k2sVp8QvJlOllLDoC
 m7rPoq98jC6VpZwFJ+fGk2jC7y4+1QXrOuQMy7LRTe59Thp6wUFDDPtkKfr5scDC
 UxkctlUdInD7A6DVvPzwaBFNoT8UeEByGHcMd3KjjrTdmqSWW6k8FiF4ckZwA3zJ
 oPdJVzdC5a2W7t6BHw+t7VNmkKd+swnr2sVSGQ8eIzF7z3/JSqyYVwziOD1YzAdU
 QUmawWm4/SFvsbO8aoLrEKNbUiTgQwVbKzJh4Dhu9VJ43jeCwCX7pa/uZI4evgyG
 T0tuwm58bWCk4y1o1fcFYgf4JcVgK23F2vKckUFZeHoV3Q8R0DnPCCGTqs1qT5vY
 irZ9AIawmaR09JptMjjsAEjDA9qb16Ut/J6/anukyCgL610EyYZG7zb1WH1cUD1o
 zNXY6O/iKyNdiXj7V1fTMiG/M8hGDcFu4pOpBk3hFjHEXX9BefoVC0J5YzvCecPz
 isqboD5Lt1I4mrzac1X+serMYfVbFH6+tsEPBQBZf/o/a0u43jI=
 =Cxvn
 -----END PGP SIGNATURE-----

Merge tag 'for-5.19-rc6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs fixes from David Sterba:
 "A more fixes that seem to me to be important enough to get merged
  before release:

   - in zoned mode, fix leak of a structure when reading zone info, this
     happens on normal path so this can be significant

   - in zoned mode, revert an optimization added in 5.19-rc1 to finish a
     zone when the capacity is full, but this is not reliable in all
     cases

   - try to avoid short reads for compressed data or inline files when
     it's a NOWAIT read, applications should handle that but there are
     two, qemu and mariadb, that are affected"

* tag 'for-5.19-rc6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: zoned: drop optimization of zone finish
  btrfs: zoned: fix a leaked bioc in read_zone_info
  btrfs: return -EAGAIN for NOWAIT dio reads/writes on compressed and inline extents
2022-07-11 14:41:44 -07:00
Filipe Manana
a4527e1853 btrfs: return -EAGAIN for NOWAIT dio reads/writes on compressed and inline extents
When doing a direct IO read or write, we always return -ENOTBLK when we
find a compressed extent (or an inline extent) so that we fallback to
buffered IO. This however is not ideal in case we are in a NOWAIT context
(io_uring for example), because buffered IO can block and we currently
have no support for NOWAIT semantics for buffered IO, so if we need to
fallback to buffered IO we should first signal the caller that we may
need to block by returning -EAGAIN instead.

This behaviour can also result in short reads being returned to user
space, which although it's not incorrect and user space should be able
to deal with partial reads, it's somewhat surprising and even some popular
applications like QEMU (Link tag #1) and MariaDB (Link tag #2) don't
deal with short reads properly (or at all).

The short read case happens when we try to read from a range that has a
non-compressed and non-inline extent followed by a compressed extent.
After having read the first extent, when we find the compressed extent we
return -ENOTBLK from btrfs_dio_iomap_begin(), which results in iomap to
treat the request as a short read, returning 0 (success) and waiting for
previously submitted bios to complete (this happens at
fs/iomap/direct-io.c:__iomap_dio_rw()). After that, and while at
btrfs_file_read_iter(), we call filemap_read() to use buffered IO to
read the remaining data, and pass it the number of bytes we were able to
read with direct IO. Than at filemap_read() if we get a page fault error
when accessing the read buffer, we return a partial read instead of an
-EFAULT error, because the number of bytes previously read is greater
than zero.

So fix this by returning -EAGAIN for NOWAIT direct IO when we find a
compressed or an inline extent.

Reported-by: Dominique MARTINET <dominique.martinet@atmark-techno.com>
Link: https://lore.kernel.org/linux-btrfs/YrrFGO4A1jS0GI0G@atmark-techno.com/
Link: https://jira.mariadb.org/browse/MDEV-27900?focusedCommentId=216582&page=com.atlassian.jira.plugin.system.issuetabpanels%3Acomment-tabpanel#comment-216582
Tested-by: Dominique MARTINET <dominique.martinet@atmark-techno.com>
CC: stable@vger.kernel.org # 5.10+
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-07-08 19:13:22 +02:00
Linus Torvalds
82708bb1eb for-5.19-rc3-tag
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEE8rQSAMVO+zA4DBdWxWXV+ddtWDsFAmK4dV4ACgkQxWXV+ddt
 WDs4uQ/7B0XqPK05NJntJfwnuIoT/yOreKf47wt/6DyFV3CDMFte/qzaZwthwu6P
 F0GMpSYAlVszLlML5elvF9VXymlV+e+QROtbD6QCNLNW1IwHA7ZiF5fV/a1Rj930
 XSuaDyVFPAK7892RR6yMQ20IeMBuvqiAhXWEzaIJ2tIcAHn+fP+VkY8Nc0aZj3iC
 mI+ep4n93karDxmnHVGUxJTxAe0l/uNopx+fYBWQDj7HuoMLo0Cu+rAdv0gRIxi2
 RWUBkR4e4PBwV1OFScwNCsljjt6bHdUHrtdB3fo5Hzu9cO5hHdL7NEsKB1K2w7rV
 bgNuNqfj6Y4xUBchAfQO5CCJ9ISci5KoJ4RBpk6EprZR3QN40kN8GPlhi2519K7w
 F3d8jolDDHlkqxIsqoe47MYOcSepNEadVNsiYKb0rM6doilfxyXiu6dtTFMrC8Vy
 K2HDCdTyuIgw+TnwqT1puaUwxiIL8DFJf1CVyjwGuQ4UgaIEkHXKIsCssyyJ76Jh
 QkWX1aeRldbfkVArJWHQWqDQopx9pFBz1gjlws0YjAsU5YijOOXva464P9Rxg+Gq
 4pRlgnO48joQam9bRirP2Z6yhqa4O6jkzKDOXSYduAUYD7IMfpsYnz09wKS95jj+
 QCrR7VmKnpQdsXg5a/mqyacfIH30ph002VywRxPiFM89Syd25yo=
 =rUrf
 -----END PGP SIGNATURE-----

Merge tag 'for-5.19-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs fixes from David Sterba:

 - zoned relocation fixes:
      - fix critical section end for extent writeback, this could lead
        to out of order write
      - prevent writing to previous data relocation block group if space
        gets low

 - reflink fixes:
      - fix race between reflinking and ordered extent completion
      - proper error handling when block reserve migration fails
      - add missing inode iversion/mtime/ctime updates on each iteration
        when replacing extents

 - fix deadlock when running fsync/fiemap/commit at the same time

 - fix false-positive KCSAN report regarding pid tracking for read locks
   and data race

 - minor documentation update and link to new site

* tag 'for-5.19-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  Documentation: update btrfs list of features and link to readthedocs.io
  btrfs: fix deadlock with fsync+fiemap+transaction commit
  btrfs: don't set lock_owner when locking extent buffer for reading
  btrfs: zoned: fix critical section of relocation inode writeback
  btrfs: zoned: prevent allocation from previous data relocation BG
  btrfs: do not BUG_ON() on failure to migrate space when replacing extents
  btrfs: add missing inode updates on each iteration when replacing extents
  btrfs: fix race between reflinking and ordered extent completion
2022-06-26 10:11:36 -07:00
Naohiro Aota
343d8a3085 btrfs: zoned: prevent allocation from previous data relocation BG
After commit 5f0addf7b8 ("btrfs: zoned: use dedicated lock for data
relocation"), we observe IO errors on e.g, btrfs/232 like below.

  [09.0][T4038707] WARNING: CPU: 3 PID: 4038707 at fs/btrfs/extent-tree.c:2381 btrfs_cross_ref_exist+0xfc/0x120 [btrfs]
  <snip>
  [09.9][T4038707] Call Trace:
  [09.5][T4038707]  <TASK>
  [09.3][T4038707]  run_delalloc_nocow+0x7f1/0x11a0 [btrfs]
  [09.6][T4038707]  ? test_range_bit+0x174/0x320 [btrfs]
  [09.2][T4038707]  ? fallback_to_cow+0x980/0x980 [btrfs]
  [09.3][T4038707]  ? find_lock_delalloc_range+0x33e/0x3e0 [btrfs]
  [09.5][T4038707]  btrfs_run_delalloc_range+0x445/0x1320 [btrfs]
  [09.2][T4038707]  ? test_range_bit+0x320/0x320 [btrfs]
  [09.4][T4038707]  ? lock_downgrade+0x6a0/0x6a0
  [09.2][T4038707]  ? orc_find.part.0+0x1ed/0x300
  [09.5][T4038707]  ? __module_address.part.0+0x25/0x300
  [09.0][T4038707]  writepage_delalloc+0x159/0x310 [btrfs]
  <snip>
  [09.4][    C3] sd 10:0:1:0: [sde] tag#2620 FAILED Result: hostbyte=DID_OK driverbyte=DRIVER_OK cmd_age=0s
  [09.5][    C3] sd 10:0:1:0: [sde] tag#2620 Sense Key : Illegal Request [current]
  [09.9][    C3] sd 10:0:1:0: [sde] tag#2620 Add. Sense: Unaligned write command
  [09.5][    C3] sd 10:0:1:0: [sde] tag#2620 CDB: Write(16) 8a 00 00 00 00 00 02 f3 63 87 00 00 00 2c 00 00
  [09.4][    C3] critical target error, dev sde, sector 396041272 op 0x1:(WRITE) flags 0x800 phys_seg 3 prio class 0
  [09.9][    C3] BTRFS error (device dm-1): bdev /dev/mapper/dml_102_2 errs: wr 1, rd 0, flush 0, corrupt 0, gen 0

The IO errors occur when we allocate a regular extent in previous data
relocation block group.

On zoned btrfs, we use a dedicated block group to relocate a data
extent. Thus, we allocate relocating data extents (pre-alloc) only from
the dedicated block group and vice versa. Once the free space in the
dedicated block group gets tight, a relocating extent may not fit into
the block group. In that case, we need to switch the dedicated block
group to the next one. Then, the previous one is now freed up for
allocating a regular extent. The BG is already not enough to allocate
the relocating extent, but there is still room to allocate a smaller
extent. Now the problem happens. By allocating a regular extent while
nocow IOs for the relocation is still on-going, we will issue WRITE IOs
(for relocation) and ZONE APPEND IOs (for the regular writes) at the
same time. That mixed IOs confuses the write pointer and arises the
unaligned write errors.

This commit introduces a new bit 'zoned_data_reloc_ongoing' to the
btrfs_block_group. We set this bit before releasing the dedicated block
group, and no extent are allocated from a block group having this bit
set. This bit is similar to setting block_group->ro, but is different from
it by allowing nocow writes to start.

Once all the nocow IO for relocation is done (hooked from
btrfs_finish_ordered_io), we reset the bit to release the block group for
further allocation.

Fixes: c2707a2556 ("btrfs: zoned: add a dedicated data relocation block group")
CC: stable@vger.kernel.org # 5.16+
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-06-21 14:43:48 +02:00
Filipe Manana
983d8209c6 btrfs: add missing inode updates on each iteration when replacing extents
When replacing file extents, called during fallocate, hole punching,
clone and deduplication, we may not be able to replace/drop all the
target file extent items with a single transaction handle. We may get
-ENOSPC while doing it, in which case we release the transaction handle,
balance the dirty pages of the btree inode, flush delayed items and get
a new transaction handle to operate on what's left of the target range.

By dropping and replacing file extent items we have effectively modified
the inode, so we should bump its iversion and update its mtime/ctime
before we update the inode item. This is because if the transaction
we used for partially modifying the inode gets committed by someone after
we release it and before we finish the rest of the range, a power failure
happens, then after mounting the filesystem our inode has an outdated
iversion and mtime/ctime, corresponding to the values it had before we
changed it.

So add the missing iversion and mtime/ctime updates.

Reviewed-by: Boris Burkov <boris@bur.io>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-06-21 14:43:21 +02:00
Al Viro
eacdf4eaca btrfs: use IOMAP_DIO_NOSYNC
... instead of messing with iocb flags

Suggested-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Christian Brauner (Microsoft) <brauner@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2022-06-10 16:04:13 -04:00
Linus Torvalds
fdaf9a5840 Page cache changes for 5.19
- Appoint myself page cache maintainer
 
  - Fix how scsicam uses the page cache
 
  - Use the memalloc_nofs_save() API to replace AOP_FLAG_NOFS
 
  - Remove the AOP flags entirely
 
  - Remove pagecache_write_begin() and pagecache_write_end()
 
  - Documentation updates
 
  - Convert several address_space operations to use folios:
    - is_dirty_writeback
    - readpage becomes read_folio
    - releasepage becomes release_folio
    - freepage becomes free_folio
 
  - Change filler_t to require a struct file pointer be the first argument
    like ->read_folio
 -----BEGIN PGP SIGNATURE-----
 
 iQEzBAABCgAdFiEEejHryeLBw/spnjHrDpNsjXcpgj4FAmKNMDUACgkQDpNsjXcp
 gj4/mwf/bpHhXH4ZoNIvtUpTF6rZbqeffmc0VrbxCZDZ6igRnRPglxZ9H9v6L53O
 7B0FBQIfxgNKHZpdqGdOkv8cjg/GMe/HJUbEy5wOakYPo4L9fZpHbDZ9HM2Eankj
 xBqLIBgBJ7doKr+Y62DAN19TVD8jfRfVtli5mqXJoNKf65J7BkxljoTH1L3EXD9d
 nhLAgyQjR67JQrT/39KMW+17GqLhGefLQ4YnAMONtB6TVwX/lZmigKpzVaCi4r26
 bnk5vaR/3PdjtNxIoYvxdc71y2Eg05n2jEq9Wcy1AaDv/5vbyZUlZ2aBSaIVbtKX
 WfrhN9O3L0bU5qS7p9PoyfLc9wpq8A==
 =djLv
 -----END PGP SIGNATURE-----

Merge tag 'folio-5.19' of git://git.infradead.org/users/willy/pagecache

Pull page cache updates from Matthew Wilcox:

 - Appoint myself page cache maintainer

 - Fix how scsicam uses the page cache

 - Use the memalloc_nofs_save() API to replace AOP_FLAG_NOFS

 - Remove the AOP flags entirely

 - Remove pagecache_write_begin() and pagecache_write_end()

 - Documentation updates

 - Convert several address_space operations to use folios:
     - is_dirty_writeback
     - readpage becomes read_folio
     - releasepage becomes release_folio
     - freepage becomes free_folio

 - Change filler_t to require a struct file pointer be the first
   argument like ->read_folio

* tag 'folio-5.19' of git://git.infradead.org/users/willy/pagecache: (107 commits)
  nilfs2: Fix some kernel-doc comments
  Appoint myself page cache maintainer
  fs: Remove aops->freepage
  secretmem: Convert to free_folio
  nfs: Convert to free_folio
  orangefs: Convert to free_folio
  fs: Add free_folio address space operation
  fs: Convert drop_buffers() to use a folio
  fs: Change try_to_free_buffers() to take a folio
  jbd2: Convert release_buffer_page() to use a folio
  jbd2: Convert jbd2_journal_try_to_free_buffers to take a folio
  reiserfs: Convert release_buffer_page() to use a folio
  fs: Remove last vestiges of releasepage
  ubifs: Convert to release_folio
  reiserfs: Convert to release_folio
  orangefs: Convert to release_folio
  ocfs2: Convert to release_folio
  nilfs2: Remove comment about releasepage
  nfs: Convert to release_folio
  jfs: Convert to release_folio
  ...
2022-05-24 19:55:07 -07:00
Filipe Manana
97bdf1a903 btrfs: do not account twice for inode ref when reserving metadata units
When reserving metadata units for creating an inode, we don't need to
reserve one extra unit for the inode ref item because when creating the
inode, at btrfs_create_new_inode(), we always insert the inode item and
the inode ref item in a single batch (a single btree insert operation,
and both ending up in the same leaf).

As we have accounted already one unit for the inode item, the extra unit
for the inode ref item is superfluous, it only makes us reserve more
metadata than necessary and often adding more reclaim pressure if we are
low on available metadata space.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-17 20:15:25 +02:00
Christoph Hellwig
642c5d34da btrfs: allocate the btrfs_dio_private as part of the iomap dio bio
Create a new bio_set that contains all the per-bio private data needed
by btrfs for direct I/O and tell the iomap code to use that instead
of separately allocation the btrfs_dio_private structure.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16 17:17:33 +02:00
Christoph Hellwig
a3e171a09c btrfs: move struct btrfs_dio_private to inode.c
The btrfs_dio_private structure is only used in inode.c, so move the
definition there.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16 17:17:32 +02:00
Christoph Hellwig
acb8b52a15 btrfs: remove the disk_bytenr in struct btrfs_dio_private
This field is never used, so remove it. Last use was probably in
23ea8e5a07 ("Btrfs: load checksum data once when submitting a direct
read io").

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16 17:17:32 +02:00
Christoph Hellwig
491a6d0118 btrfs: allocate dio_data on stack
Make use of the new iomap_iter->private field to avoid a memory
allocation per iomap range.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16 17:17:32 +02:00
Christoph Hellwig
786f847f43 iomap: add per-iomap_iter private data
Allow the file system to keep state for all iterations.  For now only
wire it up for direct I/O as there is an immediate need for it there.

Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16 17:17:32 +02:00
Christoph Hellwig
36e8c62273 btrfs: add a btrfs_dio_rw wrapper
Add a wrapper around iomap_dio_rw that keeps the direct I/O internals
isolated in inode.c.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16 17:17:32 +02:00
David Sterba
cb3a12d988 btrfs: rename bio_flags in parameters and switch type
Several functions take parameter bio_flags that was simplified to just
compress type, unify it and change the type accordingly.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16 17:17:31 +02:00
David Sterba
2a5232a8ce btrfs: simplify handling of bio_ctrl::bio_flags
The bio_flags are used only to encode the compression and there are no
other EXTENT_BIO_* flags, so the compress type can be stored directly.
The struct member name is left unchanged and will be cleaned in later
patches.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16 17:17:31 +02:00
David Sterba
a6f5e39ee7 btrfs: remove unused parameter bio_flags from btrfs_wq_submit_bio
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16 17:17:31 +02:00
Filipe Manana
f5585f4f0e btrfs: fix deadlock between concurrent dio writes when low on free data space
When reserving data space for a direct IO write we can end up deadlocking
if we have multiple tasks attempting a write to the same file range, there
are multiple extents covered by that file range, we are low on available
space for data and the writes don't expand the inode's i_size.

The deadlock can happen like this:

1) We have a file with an i_size of 1M, at offset 0 it has an extent with
   a size of 128K and at offset 128K it has another extent also with a
   size of 128K;

2) Task A does a direct IO write against file range [0, 256K), and because
   the write is within the i_size boundary, it takes the inode's lock (VFS
   level) in shared mode;

3) Task A locks the file range [0, 256K) at btrfs_dio_iomap_begin(), and
   then gets the extent map for the extent covering the range [0, 128K).
   At btrfs_get_blocks_direct_write(), it creates an ordered extent for
   that file range ([0, 128K));

4) Before returning from btrfs_dio_iomap_begin(), it unlocks the file
   range [0, 256K);

5) Task A executes btrfs_dio_iomap_begin() again, this time for the file
   range [128K, 256K), and locks the file range [128K, 256K);

6) Task B starts a direct IO write against file range [0, 256K) as well.
   It also locks the inode in shared mode, as it's within the i_size limit,
   and then tries to lock file range [0, 256K). It is able to lock the
   subrange [0, 128K) but then blocks waiting for the range [128K, 256K),
   as it is currently locked by task A;

7) Task A enters btrfs_get_blocks_direct_write() and tries to reserve data
   space. Because we are low on available free space, it triggers the
   async data reclaim task, and waits for it to reserve data space;

8) The async reclaim task decides to wait for all existing ordered extents
   to complete (through btrfs_wait_ordered_roots()).
   It finds the ordered extent previously created by task A for the file
   range [0, 128K) and waits for it to complete;

9) The ordered extent for the file range [0, 128K) can not complete
   because it blocks at btrfs_finish_ordered_io() when trying to lock the
   file range [0, 128K).

   This results in a deadlock, because:

   - task B is holding the file range [0, 128K) locked, waiting for the
     range [128K, 256K) to be unlocked by task A;

   - task A is holding the file range [128K, 256K) locked and it's waiting
     for the async data reclaim task to satisfy its space reservation
     request;

   - the async data reclaim task is waiting for ordered extent [0, 128K)
     to complete, but the ordered extent can not complete because the
     file range [0, 128K) is currently locked by task B, which is waiting
     on task A to unlock file range [128K, 256K) and task A waiting
     on the async data reclaim task.

   This results in a deadlock between 4 task: task A, task B, the async
   data reclaim task and the task doing ordered extent completion (a work
   queue task).

This type of deadlock can sporadically be triggered by the test case
generic/300 from fstests, and results in a stack trace like the following:

[12084.033689] INFO: task kworker/u16:7:123749 blocked for more than 241 seconds.
[12084.034877]       Not tainted 5.18.0-rc2-btrfs-next-115 #1
[12084.035562] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[12084.036548] task:kworker/u16:7   state:D stack:    0 pid:123749 ppid:     2 flags:0x00004000
[12084.036554] Workqueue: btrfs-flush_delalloc btrfs_work_helper [btrfs]
[12084.036599] Call Trace:
[12084.036601]  <TASK>
[12084.036606]  __schedule+0x3cb/0xed0
[12084.036616]  schedule+0x4e/0xb0
[12084.036620]  btrfs_start_ordered_extent+0x109/0x1c0 [btrfs]
[12084.036651]  ? prepare_to_wait_exclusive+0xc0/0xc0
[12084.036659]  btrfs_run_ordered_extent_work+0x1a/0x30 [btrfs]
[12084.036688]  btrfs_work_helper+0xf8/0x400 [btrfs]
[12084.036719]  ? lock_is_held_type+0xe8/0x140
[12084.036727]  process_one_work+0x252/0x5a0
[12084.036736]  ? process_one_work+0x5a0/0x5a0
[12084.036738]  worker_thread+0x52/0x3b0
[12084.036743]  ? process_one_work+0x5a0/0x5a0
[12084.036745]  kthread+0xf2/0x120
[12084.036747]  ? kthread_complete_and_exit+0x20/0x20
[12084.036751]  ret_from_fork+0x22/0x30
[12084.036765]  </TASK>
[12084.036769] INFO: task kworker/u16:11:153787 blocked for more than 241 seconds.
[12084.037702]       Not tainted 5.18.0-rc2-btrfs-next-115 #1
[12084.038540] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[12084.039506] task:kworker/u16:11  state:D stack:    0 pid:153787 ppid:     2 flags:0x00004000
[12084.039511] Workqueue: events_unbound btrfs_async_reclaim_data_space [btrfs]
[12084.039551] Call Trace:
[12084.039553]  <TASK>
[12084.039557]  __schedule+0x3cb/0xed0
[12084.039566]  schedule+0x4e/0xb0
[12084.039569]  schedule_timeout+0xed/0x130
[12084.039573]  ? mark_held_locks+0x50/0x80
[12084.039578]  ? _raw_spin_unlock_irq+0x24/0x50
[12084.039580]  ? lockdep_hardirqs_on+0x7d/0x100
[12084.039585]  __wait_for_common+0xaf/0x1f0
[12084.039587]  ? usleep_range_state+0xb0/0xb0
[12084.039596]  btrfs_wait_ordered_extents+0x3d6/0x470 [btrfs]
[12084.039636]  btrfs_wait_ordered_roots+0x175/0x240 [btrfs]
[12084.039670]  flush_space+0x25b/0x630 [btrfs]
[12084.039712]  btrfs_async_reclaim_data_space+0x108/0x1b0 [btrfs]
[12084.039747]  process_one_work+0x252/0x5a0
[12084.039756]  ? process_one_work+0x5a0/0x5a0
[12084.039758]  worker_thread+0x52/0x3b0
[12084.039762]  ? process_one_work+0x5a0/0x5a0
[12084.039765]  kthread+0xf2/0x120
[12084.039766]  ? kthread_complete_and_exit+0x20/0x20
[12084.039770]  ret_from_fork+0x22/0x30
[12084.039783]  </TASK>
[12084.039800] INFO: task kworker/u16:17:217907 blocked for more than 241 seconds.
[12084.040709]       Not tainted 5.18.0-rc2-btrfs-next-115 #1
[12084.041398] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[12084.042404] task:kworker/u16:17  state:D stack:    0 pid:217907 ppid:     2 flags:0x00004000
[12084.042411] Workqueue: btrfs-endio-write btrfs_work_helper [btrfs]
[12084.042461] Call Trace:
[12084.042463]  <TASK>
[12084.042471]  __schedule+0x3cb/0xed0
[12084.042485]  schedule+0x4e/0xb0
[12084.042490]  wait_extent_bit.constprop.0+0x1eb/0x260 [btrfs]
[12084.042539]  ? prepare_to_wait_exclusive+0xc0/0xc0
[12084.042551]  lock_extent_bits+0x37/0x90 [btrfs]
[12084.042601]  btrfs_finish_ordered_io.isra.0+0x3fd/0x960 [btrfs]
[12084.042656]  ? lock_is_held_type+0xe8/0x140
[12084.042667]  btrfs_work_helper+0xf8/0x400 [btrfs]
[12084.042716]  ? lock_is_held_type+0xe8/0x140
[12084.042727]  process_one_work+0x252/0x5a0
[12084.042742]  worker_thread+0x52/0x3b0
[12084.042750]  ? process_one_work+0x5a0/0x5a0
[12084.042754]  kthread+0xf2/0x120
[12084.042757]  ? kthread_complete_and_exit+0x20/0x20
[12084.042763]  ret_from_fork+0x22/0x30
[12084.042783]  </TASK>
[12084.042798] INFO: task fio:234517 blocked for more than 241 seconds.
[12084.043598]       Not tainted 5.18.0-rc2-btrfs-next-115 #1
[12084.044282] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[12084.045244] task:fio             state:D stack:    0 pid:234517 ppid:234515 flags:0x00004000
[12084.045248] Call Trace:
[12084.045250]  <TASK>
[12084.045254]  __schedule+0x3cb/0xed0
[12084.045263]  schedule+0x4e/0xb0
[12084.045266]  wait_extent_bit.constprop.0+0x1eb/0x260 [btrfs]
[12084.045298]  ? prepare_to_wait_exclusive+0xc0/0xc0
[12084.045306]  lock_extent_bits+0x37/0x90 [btrfs]
[12084.045336]  btrfs_dio_iomap_begin+0x336/0xc60 [btrfs]
[12084.045370]  ? lock_is_held_type+0xe8/0x140
[12084.045378]  iomap_iter+0x184/0x4c0
[12084.045383]  __iomap_dio_rw+0x2c6/0x8a0
[12084.045406]  iomap_dio_rw+0xa/0x30
[12084.045408]  btrfs_do_write_iter+0x370/0x5e0 [btrfs]
[12084.045440]  aio_write+0xfa/0x2c0
[12084.045448]  ? __might_fault+0x2a/0x70
[12084.045451]  ? kvm_sched_clock_read+0x14/0x40
[12084.045455]  ? lock_release+0x153/0x4a0
[12084.045463]  io_submit_one+0x615/0x9f0
[12084.045467]  ? __might_fault+0x2a/0x70
[12084.045469]  ? kvm_sched_clock_read+0x14/0x40
[12084.045478]  __x64_sys_io_submit+0x83/0x160
[12084.045483]  ? syscall_enter_from_user_mode+0x1d/0x50
[12084.045489]  do_syscall_64+0x3b/0x90
[12084.045517]  entry_SYSCALL_64_after_hwframe+0x44/0xae
[12084.045521] RIP: 0033:0x7fa76511af79
[12084.045525] RSP: 002b:00007ffd6d6b9058 EFLAGS: 00000246 ORIG_RAX: 00000000000000d1
[12084.045530] RAX: ffffffffffffffda RBX: 00007fa75ba6e760 RCX: 00007fa76511af79
[12084.045532] RDX: 0000557b304ff3f0 RSI: 0000000000000001 RDI: 00007fa75ba4c000
[12084.045535] RBP: 00007fa75ba4c000 R08: 00007fa751b76000 R09: 0000000000000330
[12084.045537] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
[12084.045540] R13: 0000000000000000 R14: 0000557b304ff3f0 R15: 0000557b30521eb0
[12084.045561]  </TASK>

Fix this issue by always reserving data space before locking a file range
at btrfs_dio_iomap_begin(). If we can't reserve the space, then we don't
error out immediately - instead after locking the file range, check if we
can do a NOCOW write, and if we can we don't error out since we don't need
to allocate a data extent, however if we can't NOCOW then error out with
-ENOSPC. This also implies that we may end up reserving space when it's
not needed because the write will end up being done in NOCOW mode - in that
case we just release the space after we noticed we did a NOCOW write - this
is the same type of logic that is done in the path for buffered IO writes.

Fixes: f0bfa76a11 ("btrfs: fix ENOSPC failure when attempting direct IO write into NOCOW range")
CC: stable@vger.kernel.org # 5.17+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16 17:17:31 +02:00
Goldwyn Rodrigues
1d8fa2e29b btrfs: derive compression type from extent map during reads
Derive the compression type from extent map as opposed to the bio flags
passed. This makes it more precise and not reliant on function
parameters.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16 17:17:31 +02:00
Gabriel Niebler
48b36a602a btrfs: turn fs_roots_radix in btrfs_fs_info into an XArray
… rename it to simply fs_roots and adjust all usages of this object to use
the XArray API, because it is notionally easier to use and understand, as
it provides array semantics, and also takes care of locking for us,
further simplifying the code.

Also do some refactoring, esp. where the API change requires largely
rewriting some functions, anyway.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Gabriel Niebler <gniebler@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16 17:15:57 +02:00
Gabriel Niebler
253bf57555 btrfs: turn delayed_nodes_tree into an XArray
… in the btrfs_root struct and adjust all usages of this object to use
the XArray API, because it is notionally easier to use and understand,
as it provides array semantics, and also takes care of locking for us,
further simplifying the code.

Also use the opportunity to do some light refactoring.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Gabriel Niebler <gniebler@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16 17:03:16 +02:00
Christoph Hellwig
ad357938c6 btrfs: do not return errors from submit_bio_hook_t instances
Both btrfs_repair_one_sector and submit_bio_one as the direct caller of
one of the instances ignore errors as they expect the methods themselves
to call ->bi_end_io on error.  Remove the unused and dangerous return
value.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16 17:03:14 +02:00
Christoph Hellwig
cb4411dd57 btrfs: do not return errors from btrfs_submit_compressed_read
btrfs_submit_compressed_read already calls ->bi_end_io on error and
the caller must ignore the return value, so remove it.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16 17:03:14 +02:00
Christoph Hellwig
7aab8b3282 btrfs: move btrfs_readpage to extent_io.c
Keep btrfs_readpage next to btrfs_do_readpage and the other address
space operations.  This allows to keep submit_one_bio and
struct btrfs_bio_ctrl file local in extent_io.c.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16 17:03:14 +02:00
Filipe Manana
2306e83e73 btrfs: avoid double search for block group during NOCOW writes
When doing a NOCOW write, either through direct IO or buffered IO, we do
two lookups for the block group that contains the target extent: once
when we call btrfs_inc_nocow_writers() and then later again when we call
btrfs_dec_nocow_writers() after creating the ordered extent.

The lookups require taking a lock and navigating the red black tree used
to track all block groups, which can take a non-negligible amount of time
for a large filesystem with thousands of block groups, as well as lock
contention and cache line bouncing.

Improve on this by having a single block group search: making
btrfs_inc_nocow_writers() return the block group to its caller and then
have the caller pass that block group to btrfs_dec_nocow_writers().

This is part of a patchset comprised of the following patches:

  btrfs: remove search start argument from first_logical_byte()
  btrfs: use rbtree with leftmost node cached for tracking lowest block group
  btrfs: use a read/write lock for protecting the block groups tree
  btrfs: return block group directly at btrfs_next_block_group()
  btrfs: avoid double search for block group during NOCOW writes

The following test was used to test these changes from a performance
perspective:

   $ cat test.sh
   #!/bin/bash

   modprobe null_blk nr_devices=0

   NULL_DEV_PATH=/sys/kernel/config/nullb/nullb0
   mkdir $NULL_DEV_PATH
   if [ $? -ne 0 ]; then
       echo "Failed to create nullb0 directory."
       exit 1
   fi
   echo 2 > $NULL_DEV_PATH/submit_queues
   echo 16384 > $NULL_DEV_PATH/size # 16G
   echo 1 > $NULL_DEV_PATH/memory_backed
   echo 1 > $NULL_DEV_PATH/power

   DEV=/dev/nullb0
   MNT=/mnt/nullb0
   LOOP_MNT="$MNT/loop"
   MOUNT_OPTIONS="-o ssd -o nodatacow"
   MKFS_OPTIONS="-R free-space-tree -O no-holes"

   cat <<EOF > /tmp/fio-job.ini
   [io_uring_writes]
   rw=randwrite
   fsync=0
   fallocate=posix
   group_reporting=1
   direct=1
   ioengine=io_uring
   iodepth=64
   bs=64k
   filesize=1g
   runtime=300
   time_based
   directory=$LOOP_MNT
   numjobs=8
   thread
   EOF

   echo performance | \
       tee /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor

   echo
   echo "Using config:"
   echo
   cat /tmp/fio-job.ini
   echo

   umount $MNT &> /dev/null
   mkfs.btrfs -f $MKFS_OPTIONS $DEV &> /dev/null
   mount $MOUNT_OPTIONS $DEV $MNT

   mkdir $LOOP_MNT

   truncate -s 4T $MNT/loopfile
   mkfs.btrfs -f $MKFS_OPTIONS $MNT/loopfile &> /dev/null
   mount $MOUNT_OPTIONS $MNT/loopfile $LOOP_MNT

   # Trigger the allocation of about 3500 data block groups, without
   # actually consuming space on underlying filesystem, just to make
   # the tree of block group large.
   fallocate -l 3500G $LOOP_MNT/filler

   fio /tmp/fio-job.ini

   umount $LOOP_MNT
   umount $MNT

   echo 0 > $NULL_DEV_PATH/power
   rmdir $NULL_DEV_PATH

The test was run on a non-debug kernel (Debian's default kernel config),
the result were the following.

Before patchset:

  WRITE: bw=1455MiB/s (1526MB/s), 1455MiB/s-1455MiB/s (1526MB/s-1526MB/s), io=426GiB (458GB), run=300006-300006msec

After patchset:

  WRITE: bw=1503MiB/s (1577MB/s), 1503MiB/s-1503MiB/s (1577MB/s-1577MB/s), io=440GiB (473GB), run=300006-300006msec

  +3.3% write throughput and +3.3% IO done in the same time period.

The test has somewhat limited coverage scope, as with only NOCOW writes
we get less contention on the red black tree of block groups, since we
don't have the extra contention caused by COW writes, namely when
allocating data extents, pinning and unpinning data extents, but on the
hand there's access to tree in the NOCOW path, when incrementing a block
group's number of NOCOW writers.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16 17:03:13 +02:00
Qu Wenruo
c9583ada8c btrfs: avoid double clean up when submit_one_bio() failed
[BUG]
When running generic/475 with 64K page size and 4K sector size, it has a
very high chance (almost 100%) to hang, with mostly data page locked but
no one is going to unlock it.

[CAUSE]
With commit 1784b7d502 ("btrfs: handle csum lookup errors properly on
reads"), if we failed to lookup checksum due to metadata IO error, we
will return error for btrfs_submit_data_bio().

This will cause the page to be unlocked twice in btrfs_do_readpage():

 btrfs_do_readpage()
 |- submit_extent_page()
 |  |- submit_one_bio()
 |     |- btrfs_submit_data_bio()
 |        |- if (ret) {
 |        |-     bio->bi_status = ret;
 |        |-     bio_endio(bio); }
 |               In the endio function, we will call end_page_read()
 |               and unlock_extent() to cleanup the subpage range.
 |
 |- if (ret) {
 |-        unlock_extent(); end_page_read() }
           Here we unlock the extent and cleanup the subpage range
           again.

For unlock_extent(), it's mostly double unlock safe.

But for end_page_read(), it's not, especially for subpage case,
as for subpage case we will call btrfs_subpage_end_reader() to reduce
the reader number, and use that to number to determine if we need to
unlock the full page.

If double accounted, it can underflow the number and leave the page
locked without anyone to unlock it.

[FIX]
The commit 1784b7d502 ("btrfs: handle csum lookup errors properly on
reads") itself is completely fine, it's our existing code not properly
handling the error from bio submission hook properly.

This patch will make submit_one_bio() to return void so that the callers
will never be able to do cleanup when bio submission hook fails.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16 17:03:13 +02:00
Filipe Manana
490243884e btrfs: use BTRFS_DIR_START_INDEX at btrfs_create_new_inode()
We are still using the magic value of 2 at btrfs_create_new_inode(), but
there's now a constant for that, named BTRFS_DIR_START_INDEX, which was
introduced in commit 528ee69712 ("btrfs: put initial index value of a
directory in a constant"). So change that to use the constant.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16 17:03:13 +02:00
Filipe Manana
a7bb6bd4bd btrfs: do not test for free space inode during NOCOW check against file extent
When checking if we can do a NOCOW write against a range covered by a file
extent item, we do a quick a check to determine if the inode's root was
snapshotted in a generation older than the generation of the file extent
item or not. This is to quickly determine if the extent is likely shared
and avoid the expensive check for cross references (this was added in
commit 78d4295b1e ("btrfs: lift some btrfs_cross_ref_exist checks in
nocow path").

We restrict that check to the case where the inode is not a free space
inode (since commit 27a7ff554e ("btrfs: skip file_extent generation
check for free_space_inode in run_delalloc_nocow")). That is because when
we had the inode cache feature, inode caches were backed by a free space
inode that belonged to the inode's root.

However we don't have support for the inode cache feature since kernel
5.11, so we don't need this check anymore since free space inodes are
now always related to free space caches, which are always associated to
the root tree (which can't be snapshotted, and its last_snapshot field
is always 0).

So remove that condition.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16 17:03:11 +02:00
Filipe Manana
619104ba45 btrfs: move common NOCOW checks against a file extent into a helper
Verifying if we can do a NOCOW write against a range fully or partially
covered by a file extent item requires verifying several constraints, and
these are currently duplicated at two different places: can_nocow_extent()
and run_delalloc_nocow().

This change moves those checks into a common helper function to avoid
duplication. It adds some comments and also preserves all existing
behaviour like for example can_nocow_extent() treating errors from the
calls to btrfs_cross_ref_exist() and csum_exist_in_range() as meaning
we can not NOCOW, instead of propagating the error back to the caller.
That specific behaviour is questionable but also reasonable to some
degree.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16 17:03:11 +02:00
Sweet Tea Dorminy
dd137dd1f2 btrfs: factor out allocating an array of pages
Several functions currently populate an array of page pointers one
allocated page at a time. Factor out the common code so as to allow
improvements to all of the sites at once.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16 17:03:11 +02:00
Yu Zhe
0d031dc4aa btrfs: remove unnecessary type casts
Explicit type casts are not necessary when it's void* to another pointer
type.

Signed-off-by: Yu Zhe <yuzhe@nfschina.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16 17:03:11 +02:00
Qu Wenruo
fbca46eb46 btrfs: make nodesize >= PAGE_SIZE case to reuse the non-subpage routine
The reason why we only support 64K page size for subpage is, for 64K
page size we can ensure no matter what the nodesize is, we can fit it
into one page.

When other page size come, especially like 16K, the limitation is a bit
limiting.

To remove such limitation, we allow nodesize >= PAGE_SIZE case to go the
non-subpage routine.  By this, we can allow 4K sectorsize on 16K page
size.

Although this introduces another smaller limitation, the metadata can
not cross page boundary, which is already met by most recent mkfs.

Another small improvement is, we can avoid the overhead for metadata if
nodesize >= PAGE_SIZE.
For 4K sector size and 64K page size/node size, or 4K sector size and
16K page size/node size, we don't need to allocate extra memory for the
metadata pages.

Please note that, this patch will not yet enable other page size support
yet.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16 17:03:11 +02:00
Qu Wenruo
b06660b595 btrfs: replace memset with memzero_page in data checksum verification
The original code resets the page to 0x1 for not apparent reason, it's
been like that since the initial 2007 code added in commit 07157aacb1
("Btrfs: Add file data csums back in via hooks in the extent map code").

It could mean that a failed buffer can be detected from the data but
that's just a guess and any value is good.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ update changelog ]
Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16 17:03:10 +02:00
Filipe Manana
d4135134ab btrfs: avoid blocking on space revervation when doing nowait dio writes
When doing a NOWAIT direct IO write, if we can NOCOW then it means we can
proceed with the non-blocking, NOWAIT path. However reserving the metadata
space and qgroup meta space can often result in blocking - flushing
delalloc, wait for ordered extents to complete, trigger transaction
commits, etc, going against the semantics of a NOWAIT write.

So make the NOWAIT write path to try to reserve all the metadata it needs
without resulting in a blocking behaviour - if we get -ENOSPC or -EDQUOT
then return -EAGAIN to make the caller fallback to a blocking direct IO
write.

This is part of a patchset comprised of the following patches:

  btrfs: avoid blocking on page locks with nowait dio on compressed range
  btrfs: avoid blocking nowait dio when locking file range
  btrfs: avoid double nocow check when doing nowait dio writes
  btrfs: stop allocating a path when checking if cross reference exists
  btrfs: free path at can_nocow_extent() before checking for checksum items
  btrfs: release path earlier at can_nocow_extent()
  btrfs: avoid blocking when allocating context for nowait dio read/write
  btrfs: avoid blocking on space revervation when doing nowait dio writes

The following test was run before and after applying this patchset:

  $ cat io-uring-nodatacow-test.sh
  #!/bin/bash

  DEV=/dev/sdc
  MNT=/mnt/sdc

  MOUNT_OPTIONS="-o ssd -o nodatacow"
  MKFS_OPTIONS="-R free-space-tree -O no-holes"

  NUM_JOBS=4
  FILE_SIZE=8G
  RUN_TIME=300

  cat <<EOF > /tmp/fio-job.ini
  [io_uring_rw]
  rw=randrw
  fsync=0
  fallocate=posix
  group_reporting=1
  direct=1
  ioengine=io_uring
  iodepth=64
  bssplit=4k/20:8k/20:16k/20:32k/10:64k/10:128k/5:256k/5:512k/5:1m/5
  filesize=$FILE_SIZE
  runtime=$RUN_TIME
  time_based
  filename=foobar
  directory=$MNT
  numjobs=$NUM_JOBS
  thread
  EOF

  echo performance | \
     tee /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor

  umount $MNT &> /dev/null
  mkfs.btrfs -f $MKFS_OPTIONS $DEV &> /dev/null
  mount $MOUNT_OPTIONS $DEV $MNT

  fio /tmp/fio-job.ini

  umount $MNT

The test was run a 12 cores box with 64G of ram, using a non-debug kernel
config (Debian's default config) and a spinning disk.

Result before the patchset:

 READ: bw=407MiB/s (427MB/s), 407MiB/s-407MiB/s (427MB/s-427MB/s), io=119GiB (128GB), run=300175-300175msec
WRITE: bw=407MiB/s (427MB/s), 407MiB/s-407MiB/s (427MB/s-427MB/s), io=119GiB (128GB), run=300175-300175msec

Result after the patchset:

 READ: bw=436MiB/s (457MB/s), 436MiB/s-436MiB/s (457MB/s-457MB/s), io=128GiB (137GB), run=300044-300044msec
WRITE: bw=435MiB/s (456MB/s), 435MiB/s-435MiB/s (456MB/s-456MB/s), io=128GiB (137GB), run=300044-300044msec

That's about +7.2% throughput for reads and +6.9% for writes.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16 17:03:10 +02:00
Filipe Manana
4f208dcc6b btrfs: avoid blocking when allocating context for nowait dio read/write
When doing a NOWAIT direct IO read/write, we allocate a context object
(struct btrfs_dio_data) with GFP_NOFS, which can result in blocking
waiting for memory allocation (GFP_NOFS is __GFP_RECLAIM | __GFP_IO).
This is undesirable for the NOWAIT semantics, so do the allocation with
GFP_NOWAIT if we are serving a NOWAIT request and if the allocation fails
return -EAGAIN, so that the caller can fallback to a blocking context and
retry with a non-blocking write.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16 17:03:10 +02:00
Filipe Manana
59d35c5171 btrfs: release path earlier at can_nocow_extent()
At can_nocow_extent(), we are releasing the path only after checking if
the block group that has the target extent is read only, and after
checking if there's delalloc in the range in case our extent is a
preallocated extent. The read only extent check can be expensive if we
have a very large filesystem with many block groups, as well as the
check for delalloc in the inode's io_tree in case the io_tree is big
due to IO on other file ranges.

Our path is holding a read lock on a leaf and there's no need to keep
the lock while doing those two checks, so release the path before doing
them, immediately after the last use of the leaf.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16 17:03:10 +02:00
Filipe Manana
c1a548db25 btrfs: free path at can_nocow_extent() before checking for checksum items
When we look for checksum items, through csum_exist_in_range(), at
can_nocow_extent(), we no longer need the path that we have previously
allocated. Through csum_exist_in_range() -> btrfs_lookup_csums_range(),
we also end up allocating a path, so we are adding unnecessary extra
memory usage. So free the path before calling csum_exist_in_range().

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16 17:03:10 +02:00
Filipe Manana
1a89f17386 btrfs: stop allocating a path when checking if cross reference exists
At btrfs_cross_ref_exist() we always allocate a path, but we really don't
need to because all its callers (only 2) already have an allocated path
that is not being used when they call btrfs_cross_ref_exist(). So change
btrfs_cross_ref_exist() to take a path as an argument and update both
its callers to pass in the unused path they have when they call
btrfs_cross_ref_exist().

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16 17:03:10 +02:00
Filipe Manana
d7a8ab4e9b btrfs: avoid double nocow check when doing nowait dio writes
When doing a NOWAIT direct IO write we are checking twice if we can COW
into the target file range using can_nocow_extent() - once at the very
beginning of the write path, at btrfs_write_check() via
check_nocow_nolock(), and later again at btrfs_get_blocks_direct_write().

The can_nocow_extent() function does a lot of expensive things - searching
for the file extent item in the inode's subvolume tree, searching for the
extent item in the extent tree, checking delayed references, etc, so it
isn't a very cheap call.

We can remove the first check at btrfs_write_check(), and add there a
quick check to verify if the inode has the NODATACOW or PREALLOC flags,
and quickly bail out if it doesn't have neither of those flags, as that
means we have to COW and therefore can't comply with the NOWAIT semantics.

After this we do only one call to can_nocow_extent(), while we are at
btrfs_get_blocks_direct_write(), where we have already locked the file
range and we did a try lock on the range before, at
btrfs_dio_iomap_begin() (since the previous patch in the series).

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16 17:03:10 +02:00
Filipe Manana
5909440344 btrfs: avoid blocking nowait dio when locking file range
If we are doing a NOWAIT direct IO read/write, we can block when locking
the file range at btrfs_dio_iomap_begin(), as it's possible the range (or
a part of it) is already locked by another task (mmap writes, another
direct IO read/write racing with us, fiemap, etc). We are also waiting for
completion of any ordered extent we find in the range, which also can
block us for a significant amount of time.

There's also the incorrect fallback to buffered IO (returning -ENOTBLK)
when we are dealing with a NOWAIT request and we can't proceed. In this
case we should be returning -EAGAIN, as falling back to buffered IO can
result in blocking for many different reasons, so that the caller can
delegate a retry to a context where blocking is more acceptable.

Fix these cases by:

1) Doing a try lock on the file range and failing with -EAGAIN if we
   can not lock right away;

2) Fail with -EAGAIN if we find an ordered extent;

3) Return -EAGAIN instead of -ENOTBLK when we need to fallback to
   buffered IO and we have a NOWAIT request.

This will also allow us to avoid a duplicated check that verifies if we
are able to do a NOCOW write for NOWAIT direct IO writes, done in the
next patch.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16 17:03:09 +02:00
Filipe Manana
b023e67512 btrfs: avoid blocking on page locks with nowait dio on compressed range
If we are doing NOWAIT direct IO read/write and our inode has compressed
extents, we call filemap_fdatawrite_range() against the range in order
to wait for compressed writeback to complete, since the generic code at
iomap_dio_rw() calls filemap_write_and_wait_range() once, which is not
enough to wait for compressed writeback to complete.

This call to filemap_fdatawrite_range() can block on page locks, since
the first writepages() on a range that we will try to compress results
only in queuing a work to compress the data while holding the pages
locked.

Even though the generic code at iomap_dio_rw() will do the right thing
and return -EAGAIN for NOWAIT requests in case there are pages in the
range, we can still end up at btrfs_dio_iomap_begin() with pages in the
range because either of the following can happen:

1) Memory mapped writes, as we haven't locked the range yet;

2) Buffered reads might have started, which lock the pages, and we do
   the filemap_fdatawrite_range() call before locking the file range.

So don't call filemap_fdatawrite_range() at btrfs_dio_iomap_begin() if we
are doing a NOWAIT read/write. Instead call filemap_range_needs_writeback()
to check if there are any locked, dirty, or under writeback pages, and
return -EAGAIN if that's the case.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16 17:03:09 +02:00
Filipe Manana
63c34cb4c6 btrfs: add and use helper to assert an inode range is clean
We have four different scenarios where we don't expect to find ordered
extents after locking a file range:

1) During plain fallocate;
2) During hole punching;
3) During zero range;
4) During reflinks (both cloning and deduplication).

This is because in all these cases we follow the pattern:

1) Lock the inode's VFS lock in exclusive mode;

2) Lock the inode's i_mmap_lock in exclusive node, to serialize with
   mmap writes;

3) Flush delalloc in a file range and wait for all ordered extents
   to complete - both done through btrfs_wait_ordered_range();

4) Lock the file range in the inode's io_tree.

So add a helper that asserts that we don't have ordered extents for a
given range. Make the four scenarios listed above use this helper after
locking the respective file range.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16 17:03:09 +02:00
Sweet Tea Dorminy
6c3636ebe3 btrfs: restore inode creation before xattr setting
According to the tree checker, "all xattrs with a given objectid follow
the inode with that objectid in the tree" is an invariant. This was
broken by the recent change "btrfs: move common inode creation code into
btrfs_create_new_inode()", which moved acl creation and property
inheritance (stored in xattrs) to before inode insertion into the tree.
As a result, under certain timings, the xattrs could be written to the
tree before the inode, causing the tree checker to report violation of
the invariant.

Move property inheritance and acl creation back to their old ordering
after the inode insertion.

Suggested-by: Omar Sandoval <osandov@osandov.com>
Reported-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16 17:03:09 +02:00
Omar Sandoval
caae78e032 btrfs: move common inode creation code into btrfs_create_new_inode()
All of our inode creation code paths duplicate the calls to
btrfs_init_inode_security() and btrfs_add_link(). Subvolume creation
additionally duplicates property inheritance and the call to
btrfs_set_inode_index(). Fix this by moving the common code into
btrfs_create_new_inode(). This accomplishes a few things at once:

1. It reduces code duplication.

2. It allows us to set up the inode completely before inserting the
   inode item, removing calls to btrfs_update_inode().

3. It fixes a leak of an inode on disk in some error cases. For example,
   in btrfs_create(), if btrfs_new_inode() succeeds, then we have
   inserted an inode item and its inode ref. However, if something after
   that fails (e.g., btrfs_init_inode_security()), then we end the
   transaction and then decrement the link count on the inode. If the
   transaction is committed and the system crashes before the failed
   inode is deleted, then we leak that inode on disk. Instead, this
   refactoring aborts the transaction when we can't recover more
   gracefully.

4. It exposes various ways that subvolume creation diverges from mkdir
   in terms of inheriting flags, properties, permissions, and POSIX
   ACLs, a lot of which appears to be accidental. This patch explicitly
   does _not_ change the existing non-standard behavior, but it makes
   those differences more clear in the code and documents them so that
   we can discuss whether they should be changed.

Reviewed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16 17:03:08 +02:00
Omar Sandoval
3538d68dbd btrfs: reserve correct number of items for inode creation
The various inode creation code paths do not account for the compression
property, POSIX ACLs, or the parent inode item when starting a
transaction. Fix it by refactoring all of these code paths to use a new
function, btrfs_new_inode_prepare(), which computes the correct number
of items. To do so, it needs to know whether POSIX ACLs will be created,
so move the ACL creation into that function. To reduce the number of
arguments that need to be passed around for inode creation, define
struct btrfs_new_inode_args containing all of the relevant information.

btrfs_new_inode_prepare() will also be a good place to set up the
fscrypt context and encrypted filename in the future.

Reviewed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16 17:03:08 +02:00
Omar Sandoval
5f465bf1f1 btrfs: factor out common part of btrfs_{mknod,create,mkdir}()
btrfs_{mknod,create,mkdir}() are now identical other than the inode
initialization and some inconsequential function call order differences.
Factor out the common code to reduce code duplication.

Reviewed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16 17:03:08 +02:00
Omar Sandoval
a1fd0c35ff btrfs: allocate inode outside of btrfs_new_inode()
Instead of calling new_inode() and inode_init_owner() inside of
btrfs_new_inode(), do it in the callers. This allows us to pass in just
the inode instead of the mnt_userns and mode and removes the need for
memalloc_nofs_{save,restores}() since we do it before starting a
transaction. In create_subvol(), it also means we no longer have to look
up the inode again to instantiate it. This also paves the way for some
more cleanups in later patches.

This also removes the comments about Smack checking i_op, which are no
longer true since commit 5d6c31910b ("xattr: Add
__vfs_{get,set,remove}xattr helpers"). Now it checks inode->i_opflags &
IOP_XATTR, which is set based on sb->s_xattr.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16 17:03:08 +02:00
Gabriel Niebler
a8ce68fd04 btrfs: use btrfs_for_each_slot in btrfs_real_readdir
This function can be simplified by refactoring to use the new iterator
macro.  No functional changes.

Signed-off-by: Marcos Paulo de Souza <mpdesouza@suse.com>
Signed-off-by: Gabriel Niebler <gniebler@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16 17:03:07 +02:00
Omar Sandoval
305eaac009 btrfs: set inode flags earlier in btrfs_new_inode()
btrfs_new_inode() inherits the inode flags from the parent directory and
the mount options _after_ we fill the inode item. This works because all
of the callers of btrfs_new_inode() make further changes to the inode
and then call btrfs_update_inode(). It'd be better to fully initialize
the inode once to avoid the extra update, so as a first step, set the
inode flags _before_ filling the inode item.

Reviewed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16 17:03:06 +02:00
Omar Sandoval
6437d45835 btrfs: move btrfs_get_free_objectid() call into btrfs_new_inode()
Every call of btrfs_new_inode() is immediately preceded by a call to
btrfs_get_free_objectid(). Since getting an inode number is part of
creating a new inode, this is better off being moved into
btrfs_new_inode(). While we're here, get rid of the comment about
reclaiming inode numbers, since we only did that when using the ino
cache, which was removed by commit 5297199a8b ("btrfs: remove inode
number cache feature").

Reviewed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16 17:03:06 +02:00
Omar Sandoval
23c24ef8e4 btrfs: don't pass parent objectid to btrfs_new_inode() explicitly
For everything other than a subvolume root inode, we get the parent
objectid from the parent directory. For the subvolume root inode, the
parent objectid is the same as the inode's objectid. We can find this
within btrfs_new_inode() instead of passing it.

Reviewed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16 17:03:06 +02:00
Omar Sandoval
c51fa51190 btrfs: remove unnecessary set_nlink() in btrfs_create_subvol_root()
btrfs_new_inode() already returns an inode with nlink set to 1 (via
inode_init_always()). Get rid of the unnecessary set.

Reviewed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16 17:03:06 +02:00
Omar Sandoval
6d831f7ef9 btrfs: remove unnecessary inode_set_bytes(0) call
new_inode() always returns an inode with i_blocks and i_bytes set to 0
(via inode_init_always()). Remove the unnecessary call to
inode_set_bytes() in btrfs_new_inode().

Reviewed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16 17:03:06 +02:00
Omar Sandoval
9124e15f27 btrfs: remove unnecessary btrfs_i_size_write(0) calls
btrfs_new_inode() always returns an inode with i_size and disk_i_size
set to 0 (via inode_init_always() and btrfs_alloc_inode(),
respectively). Remove the unnecessary calls to btrfs_i_size_write() in
btrfs_mkdir() and btrfs_create_subvol_root().

Reviewed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16 17:03:06 +02:00
Omar Sandoval
81512e89f2 btrfs: get rid of btrfs_add_nondir()
This is a trivial wrapper around btrfs_add_link(). The only thing it
does other than moving arguments around is translating a > 0 return
value to -EEXIST. As far as I can tell, btrfs_add_link() won't return >
0 (and if it did, the existing callsites in, e.g., btrfs_mkdir() would
be broken). The check itself dates back to commit 2c90e5d658 ("Btrfs:
still corruption hunting"), so it's probably left over from debugging.
Let's just get rid of btrfs_add_nondir().

Reviewed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16 17:03:06 +02:00
Omar Sandoval
c162187143 btrfs: reserve correct number of items for rename
btrfs_rename() and btrfs_rename_exchange() don't account for enough
items. Replace the incorrect explanations with a specific breakdown of
the number of items and account them accurately.

Note that this glosses over RENAME_WHITEOUT because the next commit is
going to rework that, too.

Reviewed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16 17:03:06 +02:00
Omar Sandoval
bca4ad7c0b btrfs: reserve correct number of items for unlink and rmdir
__btrfs_unlink_inode() calls btrfs_update_inode() on the parent
directory in order to update its size and sequence number. Make sure we
account for it.

Reviewed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16 17:03:05 +02:00
Matthew Wilcox (Oracle)
f913cff350 btrfs: Convert to release_folio
I've only converted the outer layers of the btrfs release_folio paths
to use folios; the use of folios should be pushed further down into
btrfs from here.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
2022-05-09 23:12:32 -04:00
Matthew Wilcox (Oracle)
fb12489b0d btrfs: Convert btrfs to read_folio
This is a "weak" conversion which converts straight back to using pages.
A full conversion should be performed at some point, hopefully by
someone familiar with the filesystem.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
2022-05-09 16:21:45 -04:00
Linus Torvalds
9050ba3a61 for-5.18-rc5-tag
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEE8rQSAMVO+zA4DBdWxWXV+ddtWDsFAmJwBoQACgkQxWXV+ddt
 WDu/FQ/+L2LpN5Zu1NkjOAh2Lcvz5RYZjcVext4bbPUW2yhXYH3e6836R/feLOCG
 RxRICOAQhJ7I6ct/N1aToI2AbjWnMSJK+IgageA1UdIS8McbcSP/qJOYwJ/+2Xhl
 AvK5psoj+qwGbTI9e0luNe6b+UWTGIMyYRjmN0SlkBOdg9/xqQpBMQxfKJumMvEc
 3ZwLpcNjhUUwdFKHvHZNCOQhZiZwloKFeq9MLaEL5LO30wKSY6ShiCA3pafFoVN0
 mvEEVtIGgZUsgeQTzSzD8UhGDvZtZ1+aaX0dcNMRzwI2h2pkBmPkd5QtFM9Qs0xP
 hGibSN9bC/SzQyE9v4cKohwS+g4dE4r+dUWFNpdZLIOpBt5PJBDA0tjcjxquFtMr
 6JX77coAl9kt0jspBmHVPb3qmIc1Xo3Iw2PrVgTK14QUo46XwF5Rga68wKOfNt0u
 LbD9+KCLnwxoOhvXh/LJX6nvPT8tuMrT/5AOXULI2oMCnpCY6Vl+kX8zFlAfbDk1
 d4/jy42bgHCso60j2vAcdQmZB+/snpboOhKJwkE2FqOTs+hBR8PBln6BqEt5xkHZ
 q2mBfYDujnmZWaiAU6+ETjOcCooWQioi3335tp/C9TdOrIkFDij1ztYRxhgP0g0X
 w6d6wlbkcol1Zubb/zEiBiwe+6GR/KtNYc4PBEfVe5Vw0npFreU=
 =7k9f
 -----END PGP SIGNATURE-----

Merge tag 'for-5.18-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs fixes from David Sterba:
 "A few more fixes mostly around how some file attributes could be set.

   - fix handling of compression property:
      - don't allow setting it on anything else than regular file or
        directory
      - do not allow setting it on nodatacow files via properties

   - improved error handling when setting xattr

   - make sure symlinks are always properly logged"

* tag 'for-5.18-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: skip compression property for anything other than files and dirs
  btrfs: do not BUG_ON() on failure to update inode when setting xattr
  btrfs: always log symlinks in full mode
  btrfs: do not allow compression on nodatacow files
  btrfs: export a helper for compression hard check
2022-05-02 10:09:02 -07:00
Chung-Chiang Cheng
e6f9d69648 btrfs: export a helper for compression hard check
inode_can_compress will be used outside of inode.c to check the
availability of setting compression flag by xattr. This patch moves
this function as an internal helper and renames it to
btrfs_inode_can_compress.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Chung-Chiang Cheng <cccheng@synology.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-04-27 22:15:40 +02:00
Linus Torvalds
fd574a2f84 for-5.18-rc4-tag
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEE8rQSAMVO+zA4DBdWxWXV+ddtWDsFAmJnGGIACgkQxWXV+ddt
 WDumDw//cE1NcawdnVkEaKr20PetHfzPyFSIIr17nedtnVvWYyOFF/0uJlHNhv8Z
 CZIfJ7fmH/pO5oWPXN84wKNfumDWNwc36QrvoXC67TrKUSiBN8BzL83HvAjGwYFH
 G+LfZXGnVbqq8F1iYkIsuH0Oo1x/N/LPM3s6iZy3O4l8s96u+J4GRnc8Tr0AH4MA
 zgz3fab8Ec378HTG9fvdAQNLxFEe0VatD6WrzILnmM8UgeQK7g73dqH9Ni9gz2DW
 2GDlO6aevQ1G6dm2AJ0ItExnbHH7TfOThkG56Gdqrzb/d39GzrVpeob7QiorETus
 EWS1rXaeikUiD4Bzt/RszUNL80yMN1DjcN3QBkiDf3ShSDFteoHMPw3e6jcQCy1m
 Dxf5oditQqltuFNLeSiVbZEMw2kXqBP7RoPiirF9rdvrDNLHhAE9wu0kpSGSSvT7
 Tyu9JyLw2axU6wGTi1GHAXurlW2ItRRyFAewWWul1lLkuz/6YXI4F/EHm3Mbh6Nh
 pMIFMNr4Oafdx+3Ful8ZA4PynirXub/xVDefcFBibz/PTGEnHG4ZVzRudmVnowh7
 GP2pql1+Y/TFkXdD98V8GWD+E10JAmNCkQSoiggJooNWR28whukmDVX/HY8lGmWg
 DjxwGkte3SltUBWNOTGnO7546hMwOxOPZHENPh+gffYkeMeIxPI=
 =xDWz
 -----END PGP SIGNATURE-----

Merge tag 'for-5.18-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs fixes from David Sterba:

 - direct IO fixes:

      - restore passing file offset to correctly calculate checksums
        when repairing on read and bio split happens

      - use correct bio when sumitting IO on zoned filesystem

 - zoned mode fixes:

      - fix selection of device to correctly calculate device
        capabilities when allocating a new bio

      - use a dedicated lock for exclusion during relocation

      - fix leaked plug after failure syncing log

 - fix assertion during scrub and relocation

* tag 'for-5.18-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: zoned: use dedicated lock for data relocation
  btrfs: fix assertion failure during scrub due to block group reallocation
  btrfs: fix direct I/O writes for split bios on zoned devices
  btrfs: fix direct I/O read repair for split bios
  btrfs: fix and document the zoned device choice in alloc_new_bio
  btrfs: fix leaked plug after failure syncing log on zoned filesystems
2022-04-26 11:10:42 -07:00
Christoph Hellwig
0fdf977d45 btrfs: fix direct I/O writes for split bios on zoned devices
When a bio is split in btrfs_submit_direct, dip->file_offset contains
the file offset for the first bio.  But this means the start value used
in btrfs_end_dio_bio to record the write location for zone devices is
incorrect for subsequent bios.

CC: stable@vger.kernel.org # 5.16+
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Naohiro Aota <naohiro.aota@wdc.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-04-19 15:45:04 +02:00
Christoph Hellwig
00d825258b btrfs: fix direct I/O read repair for split bios
When a bio is split in btrfs_submit_direct, dip->file_offset contains
the file offset for the first bio.  But this means the start value used
in btrfs_check_read_dio_bio is incorrect for subsequent bios.  Add
a file_offset field to struct btrfs_bio to pass along the correct offset.

Given that check_data_csum only uses start of an error message this
means problems with this miscalculation will only show up when I/O fails
or checksums mismatch.

The logic was removed in f4f39fc5dc ("btrfs: remove btrfs_bio::logical
member") but we need it due to the bio splitting.

CC: stable@vger.kernel.org # 5.16+
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Naohiro Aota <naohiro.aota@wdc.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-04-19 15:44:56 +02:00
Linus Torvalds
722985e2f6 for-5.18-rc2-tag
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEE8rQSAMVO+zA4DBdWxWXV+ddtWDsFAmJUfvwACgkQxWXV+ddt
 WDtiuA//csj0CrJq7wyRvgDkbPtCCMyDtL4zfmjP4s++NWaMDOKTxBU8msuGUJgR
 Xribel2zWqlFiOzptd9sGEfxfKfz1p5Rm/gtFj57WVSGV7YtiAGyFGuzn/vpCrgq
 NP5LFY2z5N36VxDXUPKHzvdqczO5W2n9KdaysJCr6FpCz+vVrplFiT5U+X175Sgg
 zWS/XrPIHYbtaEFdb3rUKol6riu7vXW3MxEA9di8K4Xo9TJrp0NtBoGZDsWFQxf7
 vfVwtYsQPsACJxw+MjBcVQ5fNXO5iATL1JfBb9ltN589xouja7bDCb40Fm2gEwWB
 IUatnCq/4MN2S2NdPtEcXQ52W9svT/87z6ZblefSEiQqvQBBJHN131RTM/s8LBG4
 fkHcGV6PsiutSIFycrID0bpXr1Mhvg2aMjxdriLPBtYopaMPh+ivK6LPYoE5MggQ
 /rshWfjiWJhPKXPsng+H7UGbViOiYeG0kUBuaqFx4ARnESpN1gF2dJRYvXYFL/8a
 Q0wmLr1tf3M82VAaAFNOl/BVk8blutCSHcJDLDKxcl3DhVVlY5J8onEPXjneJRkk
 rRB3zoxLlptgfW75CPNyFrpicPdAXzGCoccienIUoEdHSX/W5rNA4L6XpVE5Hv94
 dWR1aVAbCUcuhY1QfBU7H2iYw0RHzqDO3+IRfqJuYsLGciijLbs=
 =APMY
 -----END PGP SIGNATURE-----

Merge tag 'for-5.18-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs fixes from David Sterba:
 "A few more code and warning fixes.

  There's one feature ioctl removal patch slated for 5.18 that did not
  make it to the main pull request. It's just a one-liner and the ioctl
  has a v2 that's in use for a long time, no point to postpone it to
  5.19.

  Late update:

   - remove balance v1 ioctl, superseded by v2 in 2012

  Fixes:

   - add back cgroup attribution for compressed writes

   - add super block write start/end annotations to asynchronous balance

   - fix root reference count on an error handling path

   - in zoned mode, activate zone at the chunk allocation time to avoid
     ENOSPC due to timing issues

   - fix delayed allocation accounting for direct IO

  Warning fixes:

   - simplify assertion condition in zoned check

   - remove an unused variable"

* tag 'for-5.18-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: fix btrfs_submit_compressed_write cgroup attribution
  btrfs: fix root ref counts in error handling in btrfs_get_root_ref
  btrfs: zoned: activate block group only for extent allocation
  btrfs: return allocated block group from do_chunk_alloc()
  btrfs: mark resumed async balance as writing
  btrfs: remove support of balance v1 ioctl
  btrfs: release correct delalloc amount in direct IO write path
  btrfs: remove unused variable in btrfs_{start,write}_dirty_block_groups()
  btrfs: zoned: remove redundant condition in btrfs_run_delalloc_range
2022-04-14 10:58:27 -07:00
Naohiro Aota
6d82ad13c4 btrfs: release correct delalloc amount in direct IO write path
Running generic/406 causes the following WARNING in btrfs_destroy_inode()
which tells there are outstanding extents left.

In btrfs_get_blocks_direct_write(), we reserve a temporary outstanding
extents with btrfs_delalloc_reserve_metadata() (or indirectly from
btrfs_delalloc_reserve_space(()). We then release the outstanding extents
with btrfs_delalloc_release_extents(). However, the "len" can be modified
in the COW case, which releases fewer outstanding extents than expected.

Fix it by calling btrfs_delalloc_release_extents() for the original length.

To reproduce the warning, the filesystem should be 1 GiB.  It's
triggering a short-write, due to not being able to allocate a large
extent and instead allocating a smaller one.

  WARNING: CPU: 0 PID: 757 at fs/btrfs/inode.c:8848 btrfs_destroy_inode+0x1e6/0x210 [btrfs]
  Modules linked in: btrfs blake2b_generic xor lzo_compress
  lzo_decompress raid6_pq zstd zstd_decompress zstd_compress xxhash zram
  zsmalloc
  CPU: 0 PID: 757 Comm: umount Not tainted 5.17.0-rc8+ #101
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS d55cb5a 04/01/2014
  RIP: 0010:btrfs_destroy_inode+0x1e6/0x210 [btrfs]
  RSP: 0018:ffffc9000327bda8 EFLAGS: 00010206
  RAX: 0000000000000000 RBX: ffff888100548b78 RCX: 0000000000000000
  RDX: 0000000000026900 RSI: 0000000000000000 RDI: ffff888100548b78
  RBP: ffff888100548940 R08: 0000000000000000 R09: ffff88810b48aba8
  R10: 0000000000000001 R11: ffff8881004eb240 R12: ffff88810b48a800
  R13: ffff88810b48ec08 R14: ffff88810b48ed00 R15: ffff888100490c68
  FS:  00007f8549ea0b80(0000) GS:ffff888237c00000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 00007f854a09e733 CR3: 000000010a2e9003 CR4: 0000000000370eb0
  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  Call Trace:
   <TASK>
   destroy_inode+0x33/0x70
   dispose_list+0x43/0x60
   evict_inodes+0x161/0x1b0
   generic_shutdown_super+0x2d/0x110
   kill_anon_super+0xf/0x20
   btrfs_kill_super+0xd/0x20 [btrfs]
   deactivate_locked_super+0x27/0x90
   cleanup_mnt+0x12c/0x180
   task_work_run+0x54/0x80
   exit_to_user_mode_prepare+0x152/0x160
   syscall_exit_to_user_mode+0x12/0x30
   do_syscall_64+0x42/0x80
   entry_SYSCALL_64_after_hwframe+0x44/0xae
   RIP: 0033:0x7f854a000fb7

Fixes: f0bfa76a11 ("btrfs: fix ENOSPC failure when attempting direct IO write into NOCOW range")
CC: stable@vger.kernel.org # 5.17
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Tested-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-04-06 00:49:35 +02:00
Haowen Bai
9435be734a btrfs: zoned: remove redundant condition in btrfs_run_delalloc_range
The logic !A || A && B is equivalent to !A || B. so we can
make code clear.

Note: though it's preferred to be in the more human readable form, there
have been repeated reports and patches as the expression is detected by
tools so apply it to reduce the load.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Haowen Bai <baihaowen@meizu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ add note ]
Signed-off-by: David Sterba <dsterba@suse.com>
2022-04-06 00:49:09 +02:00
Linus Torvalds
ce4c854ee8 for-5.18-rc1-tag
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEE8rQSAMVO+zA4DBdWxWXV+ddtWDsFAmJLaJoACgkQxWXV+ddt
 WDvd3g/+KXpWfPOg4h7rCKiZJoE0/XnAaqHacGmIy/8+TqiFm7VEdG2uA4wEjqYq
 yeCr+2NhsWcGKOWARUPmP8sBmla98tE0+1abxQFYhGdsLMcgbI6EyW+j53E7++gY
 0j4ZY4s7c1c4lsyStNrS7kauDcbZ3MHWhG1VNdTyWCf6wal/5jU93SwdDSz81Int
 iD8y2nVQoHcWdyBbPA7t9dYL5cCGR425gRrSb3Yhvc3cI6KJLbPLDpt1AAnR6XVx
 W/ELKYMVBF70nTqp3ptBTfbmm83/AcrA1/Epoe2sEV+3gaejx1vkIYwcWlvgW//+
 e980zd0k/QSse8O8s66Z7c9QnLML+L/6xxK2vJObw85NFzEGkrmoZdCa7HyyI3MS
 pkI0ox9z4I4OEgzBaH8ZpUYgRxQlRnbDv58GrTs/aEBuNaHGQJfiCmh4sx75jGvR
 eXMnqmL/EIKqZqTsLfWVuMLC7ZgTG8V76VOJ3gDE4v5Yxi306bCLcdTS+0HYz5GA
 fkCisFy69jSbkMbOClTegCkYiRHxV6GjI19yPqj29OsnFpk+htnubOvgs3Q1link
 odpBavejmbVxffrYw92Qm7NRMEldZoSaMa39zFJ9Wgtwui7Oe66K3JFlrSnth5mD
 YowfkApQCzsSiXzitwLEHmfs7F1MVh2a0jY4hTz1XrizxZPWKHE=
 =XZaw
 -----END PGP SIGNATURE-----

Merge tag 'for-5.18-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs fixes from David Sterba:

 - prevent deleting subvolume with active swapfile

 - fix qgroup reserve limit calculation overflow

 - remove device count in superblock and its item in one transaction so
   they cant't get out of sync

 - skip defragmenting an isolated sector, this could cause some extra IO

 - unify handling of mtime/permissions in hole punch with fallocate

 - zoned mode fixes:
     - remove assert checking for only single mode, we have the
       DUP mode implemented
     - fix potential lockdep warning while traversing devices
       when checking for zone activation

* tag 'for-5.18-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: prevent subvol with swapfile from being deleted
  btrfs: do not warn for free space inode in cow_file_range
  btrfs: avoid defragging extents whose next extents are not targets
  btrfs: fix fallocate to use file_modified to update permissions consistently
  btrfs: remove device item and update super block in the same transaction
  btrfs: fix qgroup reserve overflow the qgroup limit
  btrfs: zoned: remove left over ASSERT checking for single profile
  btrfs: zoned: traverse devices under chunk_mutex in btrfs_can_activate_zone
2022-04-05 08:59:37 -07:00
Matthew Wilcox (Oracle)
5a60542c61 btrfs: Remove a use of PAGE_SIZE in btrfs_invalidate_folio()
While btrfs doesn't use large folios yet, this should have been changed
as part of the conversion from invalidatepage to invalidate_folio.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
2022-04-01 14:40:44 -04:00
Kaiwen Hu
60021bd754 btrfs: prevent subvol with swapfile from being deleted
A subvolume with an active swapfile must not be deleted otherwise it
would not be possible to deactivate it.

After the subvolume is deleted, we cannot swapoff the swapfile in this
deleted subvolume because the path is unreachable.  The swapfile is
still active and holding references, the filesystem cannot be unmounted.

The test looks like this:

  mkfs.btrfs -f $dev > /dev/null
  mount $dev $mnt

  btrfs sub create $mnt/subvol
  touch $mnt/subvol/swapfile
  chmod 600 $mnt/subvol/swapfile
  chattr +C $mnt/subvol/swapfile
  dd if=/dev/zero of=$mnt/subvol/swapfile bs=1K count=4096
  mkswap $mnt/subvol/swapfile
  swapon $mnt/subvol/swapfile

  btrfs sub delete $mnt/subvol
  swapoff $mnt/subvol/swapfile  # failed: No such file or directory
  swapoff --all

  unmount $mnt                  # target is busy.

To prevent above issue, we simply check that whether the subvolume
contains any active swapfile, and stop the deleting process.  This
behavior is like snapshot ioctl dealing with a swapfile.

CC: stable@vger.kernel.org # 5.4+
Reviewed-by: Robbie Ko <robbieko@synology.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Kaiwen Hu <kevinhu@synology.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-03-24 17:50:57 +01:00
Josef Bacik
a7d16d9a07 btrfs: do not warn for free space inode in cow_file_range
This is a long time leftover from when I originally added the free space
inode, the point was to catch cases where we weren't honoring the NOCOW
flag.  However there exists a race with relocation, if we allocate our
free space inode in a block group that is about to be relocated, we
could trigger the COW path before the relocation has the opportunity to
find the extents and delete the free space cache.  In production where
we have auto-relocation enabled we're seeing this WARN_ON_ONCE() around
5k times in a 2 week period, so not super common but enough that it's at
the top of our metrics.

We're properly handling the error here, and with us phasing out v1 space
cache anyway just drop the WARN_ON_ONCE.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-03-24 17:50:53 +01:00
Linus Torvalds
6b1f86f8e9 Filesystem folio changes for 5.18
Primarily this series converts some of the address_space operations
 to take a folio instead of a page.
 
 ->is_partially_uptodate() takes a folio instead of a page and changes the
 type of the 'from' and 'count' arguments to make it obvious they're bytes.
 ->invalidatepage() becomes ->invalidate_folio() and has a similar type change.
 ->launder_page() becomes ->launder_folio()
 ->set_page_dirty() becomes ->dirty_folio() and adds the address_space as
 an argument.
 
 There are a couple of other misc changes up front that weren't worth
 separating into their own pull request.
 -----BEGIN PGP SIGNATURE-----
 
 iQEzBAABCgAdFiEEejHryeLBw/spnjHrDpNsjXcpgj4FAmI4hqMACgkQDpNsjXcp
 gj7r7Af/fVJ7m8kKqjP/IayX3HiJRuIDQw+vM++BlRNXdjz+IyED6whdmFGxJeOY
 BMyT+8ApOAz7ErS4G+7fAv4ScJK/aEgFUsnSeAiCp0PliiEJ5NNJzElp6sVmQ7H5
 SX7+Ek444FZUGsQuy0qL7/ELpR3ditnD7x+5U2g0p5TeaHGUQn84crRyfR4xuhNG
 EBD9D71BOb7OxUcOHe93pTkK51QsQ0aCrcIsB1tkK5KR0BAthn1HqF7ehL90Rvrr
 omx5M7aDWGY4oj7IKrhlAs+55Ah2WaOzrZBp0FXNbr4UENDBKWKyUxErwa4xPkf6
 Gm1iQG/CspOHnxN3YWsd5WjtlL3A+A==
 =cOiq
 -----END PGP SIGNATURE-----

Merge tag 'folio-5.18b' of git://git.infradead.org/users/willy/pagecache

Pull filesystem folio updates from Matthew Wilcox:
 "Primarily this series converts some of the address_space operations to
  take a folio instead of a page.

  Notably:

   - a_ops->is_partially_uptodate() takes a folio instead of a page and
     changes the type of the 'from' and 'count' arguments to make it
     obvious they're bytes.

   - a_ops->invalidatepage() becomes ->invalidate_folio() and has a
     similar type change.

   - a_ops->launder_page() becomes ->launder_folio()

   - a_ops->set_page_dirty() becomes ->dirty_folio() and adds the
     address_space as an argument.

  There are a couple of other misc changes up front that weren't worth
  separating into their own pull request"

* tag 'folio-5.18b' of git://git.infradead.org/users/willy/pagecache: (53 commits)
  fs: Remove aops ->set_page_dirty
  fb_defio: Use noop_dirty_folio()
  fs: Convert __set_page_dirty_no_writeback to noop_dirty_folio
  fs: Convert __set_page_dirty_buffers to block_dirty_folio
  nilfs: Convert nilfs_set_page_dirty() to nilfs_dirty_folio()
  mm: Convert swap_set_page_dirty() to swap_dirty_folio()
  ubifs: Convert ubifs_set_page_dirty to ubifs_dirty_folio
  f2fs: Convert f2fs_set_node_page_dirty to f2fs_dirty_node_folio
  f2fs: Convert f2fs_set_data_page_dirty to f2fs_dirty_data_folio
  f2fs: Convert f2fs_set_meta_page_dirty to f2fs_dirty_meta_folio
  afs: Convert afs_dir_set_page_dirty() to afs_dir_dirty_folio()
  btrfs: Convert extent_range_redirty_for_io() to use folios
  fs: Convert trivial uses of __set_page_dirty_nobuffers to filemap_dirty_folio
  btrfs: Convert from set_page_dirty to dirty_folio
  fscache: Convert fscache_set_page_dirty() to fscache_dirty_folio()
  fs: Add aops->dirty_folio
  fs: Remove aops->launder_page
  orangefs: Convert launder_page to launder_folio
  nfs: Convert from launder_page to launder_folio
  fuse: Convert from launder_page to launder_folio
  ...
2022-03-22 18:26:56 -07:00
Linus Torvalds
3bf03b9a08 Merge branch 'akpm' (patches from Andrew)
Merge updates from Andrew Morton:

 - A few misc subsystems: kthread, scripts, ntfs, ocfs2, block, and vfs

 - Most the MM patches which precede the patches in Willy's tree: kasan,
   pagecache, gup, swap, shmem, memcg, selftests, pagemap, mremap,
   sparsemem, vmalloc, pagealloc, memory-failure, mlock, hugetlb,
   userfaultfd, vmscan, compaction, mempolicy, oom-kill, migration, thp,
   cma, autonuma, psi, ksm, page-poison, madvise, memory-hotplug, rmap,
   zswap, uaccess, ioremap, highmem, cleanups, kfence, hmm, and damon.

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (227 commits)
  mm/damon/sysfs: remove repeat container_of() in damon_sysfs_kdamond_release()
  Docs/ABI/testing: add DAMON sysfs interface ABI document
  Docs/admin-guide/mm/damon/usage: document DAMON sysfs interface
  selftests/damon: add a test for DAMON sysfs interface
  mm/damon/sysfs: support DAMOS stats
  mm/damon/sysfs: support DAMOS watermarks
  mm/damon/sysfs: support schemes prioritization
  mm/damon/sysfs: support DAMOS quotas
  mm/damon/sysfs: support DAMON-based Operation Schemes
  mm/damon/sysfs: support the physical address space monitoring
  mm/damon/sysfs: link DAMON for virtual address spaces monitoring
  mm/damon: implement a minimal stub for sysfs-based DAMON interface
  mm/damon/core: add number of each enum type values
  mm/damon/core: allow non-exclusive DAMON start/stop
  Docs/damon: update outdated term 'regions update interval'
  Docs/vm/damon/design: update DAMON-Idle Page Tracking interference handling
  Docs/vm/damon: call low level monitoring primitives the operations
  mm/damon: remove unnecessary CONFIG_DAMON option
  mm/damon/paddr,vaddr: remove damon_{p,v}a_{target_valid,set_operations}()
  mm/damon/dbgfs-test: fix is_target_id() change
  ...
2022-03-22 16:11:53 -07:00
Muchun Song
fd60b28842 fs: allocate inode by using alloc_inode_sb()
The inode allocation is supposed to use alloc_inode_sb(), so convert
kmem_cache_alloc() of all filesystems to alloc_inode_sb().

Link: https://lkml.kernel.org/r/20220228122126.37293-5-songmuchun@bytedance.com
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
Acked-by: Theodore Ts'o <tytso@mit.edu>		[ext4]
Acked-by: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Alex Shi <alexs@kernel.org>
Cc: Anna Schumaker <Anna.Schumaker@Netapp.com>
Cc: Chao Yu <chao@kernel.org>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Fam Zheng <fam.zheng@bytedance.com>
Cc: Jaegeuk Kim <jaegeuk@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kari Argillander <kari.argillander@gmail.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Qi Zheng <zhengqi.arch@bytedance.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Wei Yang <richard.weiyang@gmail.com>
Cc: Xiongchun Duan <duanxiongchun@bytedance.com>
Cc: Yang Shi <shy828301@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22 15:57:03 -07:00
Matthew Wilcox (Oracle)
187c82cb03 fs: Convert trivial uses of __set_page_dirty_nobuffers to filemap_dirty_folio
These filesystems use __set_page_dirty_nobuffers() either directly or
with a very thin wrapper; convert them en masse.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Tested-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Acked-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Tested-by: Mike Marshall <hubcap@omnibond.com> # orangefs
Tested-by: David Howells <dhowells@redhat.com> # afs
2022-03-15 08:34:38 -04:00
Matthew Wilcox (Oracle)
895586eb68 btrfs: Convert from invalidatepage to invalidate_folio
A lot of the underlying infrastructure in btrfs needs to be switched
over to folios, but this at least documents that invalidatepage can't
be passed a tail page.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Tested-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Acked-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Tested-by: Mike Marshall <hubcap@omnibond.com> # orangefs
Tested-by: David Howells <dhowells@redhat.com> # afs
2022-03-15 08:23:29 -04:00
Filipe Manana
23e3337faf btrfs: reset last_reflink_trans after fsyncing inode
When an inode has a last_reflink_trans matching the current transaction,
we have to take special care when logging its checksums in order to
avoid getting checksum items with overlapping ranges in a log tree,
which could result in missing checksums after log replay (more on that
in the changelogs of commit 40e046acbd ("Btrfs: fix missing data
checksums after replaying a log tree") and commit e289f03ea7 ("btrfs:
fix corrupt log due to concurrent fsync of inodes with shared extents")).
We also need to make sure a full fsync will copy all old file extent
items it finds in modified leaves, because they might have been copied
from some other inode.

However once we fsync an inode, we don't need to keep paying the price of
that extra special care in future fsyncs done in the same transaction,
unless the inode is used for another reflink operation or the full sync
flag is set on it (truncate, failure to allocate extent maps for holes,
and other exceptional and infrequent cases).

So after we fsync an inode reset its last_unlink_trans to zero. In case
another reflink happens, we continue to update the last_reflink_trans of
the inode, just as before. Also set last_reflink_trans to the generation
of the last transaction that modified the inode whenever we need to set
the full sync flag on the inode, just like when we need to load an inode
from disk after eviction.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-03-14 13:13:52 +01:00
Josef Bacik
f9f15de85d btrfs: do not double complete bio on errors during compressed reads
I hit some weird panics while fixing up the error handling from
btrfs_lookup_bio_sums().  Turns out the compression path will complete
the bio we use if we set up any of the compression bios and then return
an error, and then btrfs_submit_data_bio() will also call bio_endio() on
the bio.

Fix this by making btrfs_submit_compressed_read() responsible for
calling bio_endio() on the bio if there are any errors.  Currently it
was only doing it if we created the compression bios, otherwise it was
depending on btrfs_submit_data_bio() to do the right thing.  This
creates the above problem, so fix up btrfs_submit_compressed_read() to
always call bio_endio() in case of an error, and then simply return from
btrfs_submit_data_bio() if we had to call
btrfs_submit_compressed_read().

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-03-14 13:13:51 +01:00
Omar Sandoval
7c0c7269f7 btrfs: add BTRFS_IOC_ENCODED_WRITE
The implementation resembles direct I/O: we have to flush any ordered
extents, invalidate the page cache, and do the io tree/delalloc/extent
map/ordered extent dance. From there, we can reuse the compression code
with a minor modification to distinguish the write from writeback. This
also creates inline extents when possible.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-03-14 13:13:51 +01:00
Omar Sandoval
1881fba89b btrfs: add BTRFS_IOC_ENCODED_READ ioctl
There are 4 main cases:

1. Inline extents: we copy the data straight out of the extent buffer.
2. Hole/preallocated extents: we fill in zeroes.
3. Regular, uncompressed extents: we read the sectors we need directly
   from disk.
4. Regular, compressed extents: we read the entire compressed extent
   from disk and indicate what subset of the decompressed extent is in
   the file.

This initial implementation simplifies a few things that can be improved
in the future:

- Cases 1, 3, and 4 allocate temporary memory to read into before
  copying out to userspace.
- We don't do read repair, because it turns out that read repair is
  currently broken for compressed data.
- We hold the inode lock during the operation.

Note that we don't need to hold the mmap lock. We may race with
btrfs_page_mkwrite() and read the old data from before the page was
dirtied:

btrfs_page_mkwrite         btrfs_encoded_read
---------------------------------------------------
(enter)                    (enter)
                           btrfs_wait_ordered_range
lock_extent_bits
btrfs_page_set_dirty
unlock_extent_cached
(exit)
                           lock_extent_bits
                           read extent (dirty page hasn't been flushed,
                                        so this is the old data)
                           unlock_extent_cached
                           (exit)

we read the old data from before the page was dirtied. But, that's true
even if we were to hold the mmap lock:

btrfs_page_mkwrite               btrfs_encoded_read
-------------------------------------------------------------------
(enter)                          (enter)
                                 btrfs_inode_lock(BTRFS_ILOCK_MMAP)
down_read(i_mmap_lock) (blocked)
                                 btrfs_wait_ordered_range
                                 lock_extent_bits
				 read extent (page hasn't been dirtied,
                                              so this is the old data)
                                 unlock_extent_cached
                                 btrfs_inode_unlock(BTRFS_ILOCK_MMAP)
down_read(i_mmap_lock) returns
lock_extent_bits
btrfs_page_set_dirty
unlock_extent_cached

In other words, this is inherently racy, so it's fine that we return the
old data in this tiny window.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-03-14 13:13:51 +01:00
Omar Sandoval
d9496e8aba btrfs: optionally extend i_size in cow_file_range_inline()
Currently, an inline extent is always created after i_size is extended
from btrfs_dirty_pages(). However, for encoded writes, we only want to
update i_size after we successfully created the inline extent. Add an
update_i_size parameter to cow_file_range_inline() and
insert_inline_extent() and pass in the size of the extent rather than
determining it from i_size.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ reformat comment ]
Signed-off-by: David Sterba <dsterba@suse.com>
2022-03-14 13:13:51 +01:00
Omar Sandoval
8dd9872d2e btrfs: clean up cow_file_range_inline()
The start parameter to cow_file_range_inline() (and
insert_inline_extent()) is always 0, so get rid of it and simplify the
logic in those two functions. Pass btrfs_inode to insert_inline_extent()
and remove the redundant root parameter. Also document the requirements
for creating an inline extent. No functional change.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-03-14 13:13:51 +01:00
Omar Sandoval
28c9b1e75a btrfs: support different disk extent size for delalloc
Currently, we always reserve the same extent size in the file and extent
size on disk for delalloc because the former is the worst case for the
latter. For BTRFS_IOC_ENCODED_WRITE writes, we know the exact size of
the extent on disk, which may be less than or greater than (for
bookends) the size in the file. Add a disk_num_bytes parameter to
btrfs_delalloc_reserve_metadata() so that we can reserve the correct
amount of csum bytes. No functional change.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-03-14 13:13:51 +01:00
Omar Sandoval
cb36a9bb17 btrfs: add ram_bytes and offset to btrfs_ordered_extent
Currently, we only create ordered extents when ram_bytes == num_bytes
and offset == 0. However, BTRFS_IOC_ENCODED_WRITE writes may create
extents which only refer to a subset of the full unencoded extent, so we
need to plumb these fields through the ordered extent infrastructure and
pass them down to insert_reserved_file_extent().

Since we're changing the btrfs_add_ordered_extent* signature, let's get
rid of the trivial wrappers and add a kernel-doc.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-03-14 13:13:51 +01:00
Omar Sandoval
e331f6b19f btrfs: don't advance offset for compressed bios in btrfs_csum_one_bio()
btrfs_csum_one_bio() loops over each filesystem block in the bio while
keeping a cursor of its current logical position in the file in order to
look up the ordered extent to add the checksums to. However, this
doesn't make much sense for compressed extents, as a sector on disk does
not correspond to a sector of decompressed file data. It happens to work
because:

1) the compressed bio always covers one ordered extent
2) the size of the bio is always less than the size of the ordered
   extent

However, the second point will not always be true for encoded writes.

Let's add a boolean parameter to btrfs_csum_one_bio() to indicate that
it can assume that the bio only covers one ordered extent. Since we're
already changing the signature, let's get rid of the contig parameter
and make it implied by the offset parameter, similar to the change we
recently made to btrfs_lookup_bio_sums(). Additionally, let's rename
nr_sectors to blockcount to make it clear that it's the number of
filesystem blocks, not the number of 512-byte sectors.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-03-14 13:13:50 +01:00
Filipe Manana
bbf0ea7ea3 btrfs: fix lost error return value when reading a data page
At btrfs_do_readpage(), if we get an error when trying to lookup for an
extent map, we end up marking the page with the error bit, clearing
the uptodate bit on it, and doing everything else that should be done.
However we return success (0) to the caller, when we should return the
error encoded in the extent map pointer. So fix that by returning the
error encoded in the pointer.

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-03-14 13:13:50 +01:00
David Sterba
a55e65b80e btrfs: replace BUILD_BUG_ON by static_assert
The static_assert introduced in 6bab69c650 ("build_bug.h: add wrapper
for _Static_assert") has been supported by compilers for a long time
(gcc 4.6, clang 3.0) and can be used in header files. We don't need to
put BUILD_BUG_ON to random functions but rather keep it next to the
definition.

The exception here is the UAPI header btrfs_tree.h that could be
potentially included by userspace code and the static assert is not
defined (nor used in any other header).

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-03-14 13:13:49 +01:00
Josef Bacik
813febdbe6 btrfs: disable snapshot creation/deletion for extent tree v2
When we stop tracking metadata blocks all of snapshotting will break, so
disable it until I add the snapshot root and drop tree support.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-03-14 13:13:48 +01:00
Filipe Manana
259c4b96d7 btrfs: stop doing unnecessary log updates during a rename
During a rename, we call __btrfs_unlink_inode(), which will call
btrfs_del_inode_ref_in_log() and btrfs_del_dir_entries_in_log(), in order
to remove an inode reference and a directory entry from the log. These
are necessary when __btrfs_unlink_inode() is called from the unlink path,
but not necessary when it's called from a rename context, because:

1) For the btrfs_del_inode_ref_in_log() call, it's pointless to delete the
   inode reference related to the old name, because later in the rename
   path we call btrfs_log_new_name(), which will drop all inode references
   from the log and copy all inode references from the subvolume tree to
   the log tree. So we are doing one unnecessary btree operation which
   adds additional latency and lock contention in case there are other
   tasks accessing the log tree;

2) For the btrfs_del_dir_entries_in_log() call, we are now doing the
   equivalent at btrfs_log_new_name() since the previous patch in the
   series, that has the subject "btrfs: avoid logging all directory
   changes during renames". In fact, having __btrfs_unlink_inode() call
   this function not only adds additional latency and lock contention due
   to the extra btree operation, but also can make btrfs_log_new_name()
   unnecessarily log a range item to track the deletion of the old name,
   since it has no way to known that the directory entry related to the
   old name was previously logged and already deleted by
   __btrfs_unlink_inode() through its call to
   btrfs_del_dir_entries_in_log().

So skip those calls at __btrfs_unlink_inode() when we are doing a rename.
Skipping them also allows us now to reduce the duration of time we are
pinning a log transaction during renames, which is always beneficial as
it's not delaying so much other tasks trying to sync the log tree, in
particular we end up not holding the log transaction pinned while adding
the new name (adding inode ref, directory entry, etc).

This change is part of a patchset comprised of the following patches:

  1/5 btrfs: add helper to delete a dir entry from a log tree
  2/5 btrfs: pass the dentry to btrfs_log_new_name() instead of the inode
  3/5 btrfs: avoid logging all directory changes during renames
  4/5 btrfs: stop doing unnecessary log updates during a rename
  5/5 btrfs: avoid inode logging during rename and link when possible

Just like the previous patch in the series, "btrfs: avoid logging all
directory changes during renames", the following script mimics part of
what a package installation/upgrade with zypper does, which is basically
renaming a lot of files, in some directory under /usr, to a name with a
suffix of "-RPMDELETE":

  $ cat test.sh
  #!/bin/bash

  DEV=/dev/nvme0n1
  MNT=/mnt/nvme0n1

  NUM_FILES=10000

  mkfs.btrfs -f $DEV
  mount $DEV $MNT

  mkdir $MNT/testdir

  for ((i = 1; i <= $NUM_FILES; i++)); do
      echo -n > $MNT/testdir/file_$i
  done

  sync

  # Do some change to testdir and fsync it.
  echo -n > $MNT/testdir/file_$((NUM_FILES + 1))
  xfs_io -c "fsync" $MNT/testdir

  echo "Renaming $NUM_FILES files..."
  start=$(date +%s%N)
  for ((i = 1; i <= $NUM_FILES; i++)); do
      mv $MNT/testdir/file_$i $MNT/testdir/file_$i-RPMDELETE
  done
  end=$(date +%s%N)

  dur=$(( (end - start) / 1000000 ))
  echo "Renames took $dur milliseconds"

  umount $MNT

Testing this change on box a using a non-debug kernel (Debian's default
kernel config) gave the following results:

NUM_FILES=10000, before patchset:                   27399 ms
NUM_FILES=10000, after patches 1/5 to 3/5 applied:   9093 ms (-66.8%)
NUM_FILES=10000, after patches 1/5 to 4/5 applied:   9016 ms (-67.1%)

NUM_FILES=5000, before patchset:                     9241 ms
NUM_FILES=5000, after patches 1/5 to 3/5 applied:    4642 ms (-49.8%)
NUM_FILES=5000, after patches 1/5 to 4/5 applied:    4553 ms (-50.7%)

NUM_FILES=2000, before patchset:                     2550 ms
NUM_FILES=2000, after patches 1/5 to 3/5 applied:    1788 ms (-29.9%)
NUM_FILES=2000, after patches 1/5 to 4/5 applied:    1767 ms (-30.7%)

NUM_FILES=1000, before patchset:                     1088 ms
NUM_FILES=1000, after patches 1/5 to 3/5 applied:     905 ms (-16.9%)
NUM_FILES=1000, after patches 1/5 to 4/5 applied:     883 ms (-18.8%)

The next patch in the series (5/5), also contains dbench results after
applying to whole patchset.

Link: https://bugzilla.opensuse.org/show_bug.cgi?id=1193549
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-03-14 13:13:47 +01:00
Filipe Manana
88d2beec7e btrfs: avoid logging all directory changes during renames
When doing a rename of a file, if the file or its old parent directory
were logged before, we log the new name of the file and then make sure
we log the old parent directory, to ensure that after a log replay the
old name of the file is deleted and the new name added.

The logging of the old parent directory can take some time, because it
will scan all leaves modified in the current transaction, check which
directory entries were already logged, copy the ones that were not
logged before, etc. In this rename context all we need to do is make
sure that the old name of the file is deleted on log replay, so instead
of triggering a directory log operation, we can just delete the old
directory entry from the log if it's there, or in case it isn't there,
just log a range item to signal log replay that the old name must be
deleted. So change btrfs_log_new_name() to do that.

This scenario is actually not uncommon to trigger, and recently on a
5.15 kernel, an openSUSE Tumbleweed user reported package installations
and upgrades, with the zypper tool, were often taking a long time to
complete, much more than usual. With strace it could be observed that
zypper was spending over 99% of its time on rename operations, and then
with further analysis we checked that directory logging was happening
too frequently and causing high latencies for the rename operations.
Taking into account that installation/upgrade of some of these packages
needed about a few thousand file renames, the slowdown was very noticeable
for the user.

The issue was caused indirectly due to an excessive number of inode
evictions on a 5.15 kernel, about 100x more compared to a 5.13, 5.14
or a 5.16-rc8 kernel. After an inode eviction we can't tell for sure,
in an efficient way, if an inode was previously logged in the current
transaction, so we are pessimistic and assume it was, because in case
it was we need to update the logged inode. More details on that in one
of the patches in the same series (subject "btrfs: avoid inode logging
during rename and link when possible"). Either way, in case the parent
directory was logged before, we currently do more work then necessary
during a rename, and this change minimizes that amount of work.

The following script mimics part of what a package installation/upgrade
with zypper does, which is basically renaming a lot of files, in some
directory under /usr, to a name with a suffix of "-RPMDELETE":

  $ cat test.sh
  #!/bin/bash

  DEV=/dev/nvme0n1
  MNT=/mnt/nvme0n1

  NUM_FILES=10000

  mkfs.btrfs -f $DEV
  mount $DEV $MNT

  mkdir $MNT/testdir

  for ((i = 1; i <= $NUM_FILES; i++)); do
      echo -n > $MNT/testdir/file_$i
  done

  sync

  # Do some change to testdir and fsync it.
  echo -n > $MNT/testdir/file_$((NUM_FILES + 1))
  xfs_io -c "fsync" $MNT/testdir

  echo "Renaming $NUM_FILES files..."
  start=$(date +%s%N)
  for ((i = 1; i <= $NUM_FILES; i++)); do
      mv $MNT/testdir/file_$i $MNT/testdir/file_$i-RPMDELETE
  done
  end=$(date +%s%N)

  dur=$(( (end - start) / 1000000 ))
  echo "Renames took $dur milliseconds"

  umount $MNT

Testing this change on box using a non-debug kernel (Debian's default
kernel config) gave the following results:

NUM_FILES=10000, before this patch: 27399 ms
NUM_FILES=10000, after this patch:   9093 ms (-66.8%)

NUM_FILES=5000, before this patch:   9241 ms
NUM_FILES=5000, after this patch:    4642 ms (-49.8%)

NUM_FILES=2000, before this patch:   2550 ms
NUM_FILES=2000, after this patch:    1788 ms (-29.9%)

NUM_FILES=1000, before this patch:   1088 ms
NUM_FILES=1000, after this patch:     905 ms (-16.9%)

Link: https://bugzilla.opensuse.org/show_bug.cgi?id=1193549
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-03-14 13:13:47 +01:00
Filipe Manana
d5f5bd5465 btrfs: pass the dentry to btrfs_log_new_name() instead of the inode
In the next patch in the series, there will be the need to access the old
name, and its length, of an inode when logging the inode during a rename.
So instead of passing the inode to btrfs_log_new_name() pass the dentry,
because from the dentry we can get the inode, the name and its length.

This will avoid passing 3 new parameters to btrfs_log_new_name() in the
next patch - the name, its length and an index number. This way we end
up passing only 1 new parameter, the index number.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-03-14 13:13:47 +01:00
Filipe Manana
528ee69712 btrfs: put initial index value of a directory in a constant
At btrfs_set_inode_index_count() we refer twice to the number 2 as the
initial index value for a directory (when it's empty), with a proper
comment explaining the reason for that value. In the next patch I'll
have to use that magic value in the directory logging code, so put
the value in a #define at btrfs_inode.h, to avoid hardcoding the
magic value again at tree-log.c.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-03-14 13:13:46 +01:00
Filipe Manana
ca93e44bfb btrfs: fallback to blocking mode when doing async dio over multiple extents
Some users recently reported that MariaDB was getting a read corruption
when using io_uring on top of btrfs. This started to happen in 5.16,
after commit 51bd9563b6 ("btrfs: fix deadlock due to page faults
during direct IO reads and writes"). That changed btrfs to use the new
iomap flag IOMAP_DIO_PARTIAL and to disable page faults before calling
iomap_dio_rw(). This was necessary to fix deadlocks when the iovector
corresponds to a memory mapped file region. That type of scenario is
exercised by test case generic/647 from fstests.

For this MariaDB scenario, we attempt to read 16K from file offset X
using IOCB_NOWAIT and io_uring. In that range we have 4 extents, each
with a size of 4K, and what happens is the following:

1) btrfs_direct_read() disables page faults and calls iomap_dio_rw();

2) iomap creates a struct iomap_dio object, its reference count is
   initialized to 1 and its ->size field is initialized to 0;

3) iomap calls btrfs_dio_iomap_begin() with file offset X, which finds
   the first 4K extent, and setups an iomap for this extent consisting
   of a single page;

4) At iomap_dio_bio_iter(), we are able to access the first page of the
   buffer (struct iov_iter) with bio_iov_iter_get_pages() without
   triggering a page fault;

5) iomap submits a bio for this 4K extent
   (iomap_dio_submit_bio() -> btrfs_submit_direct()) and increments
   the refcount on the struct iomap_dio object to 2; The ->size field
   of the struct iomap_dio object is incremented to 4K;

6) iomap calls btrfs_iomap_begin() again, this time with a file
   offset of X + 4K. There we setup an iomap for the next extent
   that also has a size of 4K;

7) Then at iomap_dio_bio_iter() we call bio_iov_iter_get_pages(),
   which tries to access the next page (2nd page) of the buffer.
   This triggers a page fault and returns -EFAULT;

8) At __iomap_dio_rw() we see the -EFAULT, but we reset the error
   to 0 because we passed the flag IOMAP_DIO_PARTIAL to iomap and
   the struct iomap_dio object has a ->size value of 4K (we submitted
   a bio for an extent already). The 'wait_for_completion' variable
   is not set to true, because our iocb has IOCB_NOWAIT set;

9) At the bottom of __iomap_dio_rw(), we decrement the reference count
   of the struct iomap_dio object from 2 to 1. Because we were not
   the only ones holding a reference on it and 'wait_for_completion' is
   set to false, -EIOCBQUEUED is returned to btrfs_direct_read(), which
   just returns it up the callchain, up to io_uring;

10) The bio submitted for the first extent (step 5) completes and its
    bio endio function, iomap_dio_bio_end_io(), decrements the last
    reference on the struct iomap_dio object, resulting in calling
    iomap_dio_complete_work() -> iomap_dio_complete().

11) At iomap_dio_complete() we adjust the iocb->ki_pos from X to X + 4K
    and return 4K (the amount of io done) to iomap_dio_complete_work();

12) iomap_dio_complete_work() calls the iocb completion callback,
    iocb->ki_complete() with a second argument value of 4K (total io
    done) and the iocb with the adjust ki_pos of X + 4K. This results
    in completing the read request for io_uring, leaving it with a
    result of 4K bytes read, and only the first page of the buffer
    filled in, while the remaining 3 pages, corresponding to the other
    3 extents, were not filled;

13) For the application, the result is unexpected because if we ask
    to read N bytes, it expects to get N bytes read as long as those
    N bytes don't cross the EOF (i_size).

MariaDB reports this as an error, as it's not expecting a short read,
since it knows it's asking for read operations fully within the i_size
boundary. This is typical in many applications, but it may also be
questionable if they should react to such short reads by issuing more
read calls to get the remaining data. Nevertheless, the short read
happened due to a change in btrfs regarding how it deals with page
faults while in the middle of a read operation, and there's no reason
why btrfs can't have the previous behaviour of returning the whole data
that was requested by the application.

The problem can also be triggered with the following simple program:

  /* Get O_DIRECT */
  #ifndef _GNU_SOURCE
  #define _GNU_SOURCE
  #endif

  #include <stdio.h>
  #include <stdlib.h>
  #include <unistd.h>
  #include <fcntl.h>
  #include <errno.h>
  #include <string.h>
  #include <liburing.h>

  int main(int argc, char *argv[])
  {
      char *foo_path;
      struct io_uring ring;
      struct io_uring_sqe *sqe;
      struct io_uring_cqe *cqe;
      struct iovec iovec;
      int fd;
      long pagesize;
      void *write_buf;
      void *read_buf;
      ssize_t ret;
      int i;

      if (argc != 2) {
          fprintf(stderr, "Use: %s <directory>\n", argv[0]);
          return 1;
      }

      foo_path = malloc(strlen(argv[1]) + 5);
      if (!foo_path) {
          fprintf(stderr, "Failed to allocate memory for file path\n");
          return 1;
      }
      strcpy(foo_path, argv[1]);
      strcat(foo_path, "/foo");

      /*
       * Create file foo with 2 extents, each with a size matching
       * the page size. Then allocate a buffer to read both extents
       * with io_uring, using O_DIRECT and IOCB_NOWAIT. Before doing
       * the read with io_uring, access the first page of the buffer
       * to fault it in, so that during the read we only trigger a
       * page fault when accessing the second page of the buffer.
       */
       fd = open(foo_path, O_CREAT | O_TRUNC | O_WRONLY |
                O_DIRECT, 0666);
       if (fd == -1) {
           fprintf(stderr,
                   "Failed to create file 'foo': %s (errno %d)",
                   strerror(errno), errno);
           return 1;
       }

       pagesize = sysconf(_SC_PAGE_SIZE);
       ret = posix_memalign(&write_buf, pagesize, 2 * pagesize);
       if (ret) {
           fprintf(stderr, "Failed to allocate write buffer\n");
           return 1;
       }

       memset(write_buf, 0xab, pagesize);
       memset(write_buf + pagesize, 0xcd, pagesize);

       /* Create 2 extents, each with a size matching page size. */
       for (i = 0; i < 2; i++) {
           ret = pwrite(fd, write_buf + i * pagesize, pagesize,
                        i * pagesize);
           if (ret != pagesize) {
               fprintf(stderr,
                     "Failed to write to file, ret = %ld errno %d (%s)\n",
                      ret, errno, strerror(errno));
               return 1;
           }
           ret = fsync(fd);
           if (ret != 0) {
               fprintf(stderr, "Failed to fsync file\n");
               return 1;
           }
       }

       close(fd);
       fd = open(foo_path, O_RDONLY | O_DIRECT);
       if (fd == -1) {
           fprintf(stderr,
                   "Failed to open file 'foo': %s (errno %d)",
                   strerror(errno), errno);
           return 1;
       }

       ret = posix_memalign(&read_buf, pagesize, 2 * pagesize);
       if (ret) {
           fprintf(stderr, "Failed to allocate read buffer\n");
           return 1;
       }

       /*
        * Fault in only the first page of the read buffer.
        * We want to trigger a page fault for the 2nd page of the
        * read buffer during the read operation with io_uring
        * (O_DIRECT and IOCB_NOWAIT).
        */
       memset(read_buf, 0, 1);

       ret = io_uring_queue_init(1, &ring, 0);
       if (ret != 0) {
           fprintf(stderr, "Failed to create io_uring queue\n");
           return 1;
       }

       sqe = io_uring_get_sqe(&ring);
       if (!sqe) {
           fprintf(stderr, "Failed to get io_uring sqe\n");
           return 1;
       }

       iovec.iov_base = read_buf;
       iovec.iov_len = 2 * pagesize;
       io_uring_prep_readv(sqe, fd, &iovec, 1, 0);

       ret = io_uring_submit_and_wait(&ring, 1);
       if (ret != 1) {
           fprintf(stderr,
                   "Failed at io_uring_submit_and_wait()\n");
           return 1;
       }

       ret = io_uring_wait_cqe(&ring, &cqe);
       if (ret < 0) {
           fprintf(stderr, "Failed at io_uring_wait_cqe()\n");
           return 1;
       }

       printf("io_uring read result for file foo:\n\n");
       printf("  cqe->res == %d (expected %d)\n", cqe->res, 2 * pagesize);
       printf("  memcmp(read_buf, write_buf) == %d (expected 0)\n",
              memcmp(read_buf, write_buf, 2 * pagesize));

       io_uring_cqe_seen(&ring, cqe);
       io_uring_queue_exit(&ring);

       return 0;
  }

When running it on an unpatched kernel:

  $ gcc io_uring_test.c -luring
  $ mkfs.btrfs -f /dev/sda
  $ mount /dev/sda /mnt/sda
  $ ./a.out /mnt/sda
  io_uring read result for file foo:

    cqe->res == 4096 (expected 8192)
    memcmp(read_buf, write_buf) == -205 (expected 0)

After this patch, the read always returns 8192 bytes, with the buffer
filled with the correct data. Although that reproducer always triggers
the bug in my test vms, it's possible that it will not be so reliable
on other environments, as that can happen if the bio for the first
extent completes and decrements the reference on the struct iomap_dio
object before we do the atomic_dec_and_test() on the reference at
__iomap_dio_rw().

Fix this in btrfs by having btrfs_dio_iomap_begin() return -EAGAIN
whenever we try to satisfy a non blocking IO request (IOMAP_NOWAIT flag
set) over a range that spans multiple extents (or a mix of extents and
holes). This avoids returning success to the caller when we only did
partial IO, which is not optimal for writes and for reads it's actually
incorrect, as the caller doesn't expect to get less bytes read than it has
requested (unless EOF is crossed), as previously mentioned. This is also
the type of behaviour that xfs follows (xfs_direct_write_iomap_begin()),
even though it doesn't use IOMAP_DIO_PARTIAL.

A test case for fstests will follow soon.

Link: https://lore.kernel.org/linux-btrfs/CABVffEM0eEWho+206m470rtM0d9J8ue85TtR-A_oVTuGLWFicA@mail.gmail.com/
Link: https://lore.kernel.org/linux-btrfs/CAHF2GV6U32gmqSjLe=XKgfcZAmLCiH26cJ2OnHGp5x=VAH4OHQ@mail.gmail.com/
CC: stable@vger.kernel.org # 5.16+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-03-04 15:09:21 +01:00
Qu Wenruo
558732df21 btrfs: reduce extent threshold for autodefrag
There is a big gap between inode_should_defrag() and autodefrag extent
size threshold.  For inode_should_defrag() it has a flexible
@small_write value. For compressed extent is 16K, and for non-compressed
extent it's 64K.

However for autodefrag extent size threshold, it's always fixed to the
default value (256K).

This means, the following write sequence will trigger autodefrag to
defrag ranges which didn't trigger autodefrag:

  pwrite 0 8k
  sync
  pwrite 8k 128K
  sync

The latter 128K write will also be considered as a defrag target (if
other conditions are met). While only that 8K write is really
triggering autodefrag.

Such behavior can cause extra IO for autodefrag.

Close the gap, by copying the @small_write value into inode_defrag, so
that later autodefrag can use the same @small_write value which
triggered autodefrag.

With the existing transid value, this allows autodefrag really to scan
the ranges which triggered autodefrag.

Although this behavior change is mostly reducing the extent_thresh value
for autodefrag, I believe in the future we should allow users to specify
the autodefrag extent threshold through mount options, but that's an
other problem to consider in the future.

CC: stable@vger.kernel.org # 5.16+
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-02-24 16:11:28 +01:00
Filipe Manana
c2f822635d btrfs: respect the max size in the header when activating swap file
If we extended the size of a swapfile after its header was created (by the
mkswap utility) and then try to activate it, we will map the entire file
when activating the swap file, instead of limiting to the max size defined
in the swap file's header.

Currently test case generic/643 from fstests fails because we do not
respect that size limit defined in the swap file's header.

So fix this by not mapping file ranges beyond the max size defined in the
swap header.

This is the same type of bug that iomap used to have, and was fixed in
commit 36ca7943ac ("mm/swap: consider max pages in
iomap_swapfile_add_extent").

Fixes: ed46ff3d42 ("Btrfs: support swap files")
CC: stable@vger.kernel.org # 5.4+
Reviewed-and-tested-by: Josef Bacik <josef@toxicpanda.com
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-01-07 14:18:27 +01:00
Josef Bacik
71d18b5354 btrfs: add inode to truncate control
In the future we're going to want to use btrfs_truncate_inode_items
without looking up the associated inode.  In order to accommodate this
add the inode to btrfs_truncate_control and handle the case where
control->inode is NULL appropriately.  This is fairly straightforward,
we simply need to add a helper for the trace points, as the file extent
map update is controlled by a flag on btrfs_truncate_control.

Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-01-07 14:18:24 +01:00
Josef Bacik
487e81d2a4 btrfs: pass the ino via truncate control
In the future we are going to want to truncate inode items without
needing to have an btrfs_inode to pass in, so add ino to the
btrfs_truncate_control and use that to look up the inode items to
truncate.

Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-01-07 14:18:24 +01:00
Josef Bacik
655807b895 btrfs: use a flag to control when to clear the file extent range
We only care about updating the file extent range when we are doing a
normal truncation.  We skip this for tree logging currently, but we can
also skip this for eviction as well.  Using a flag makes it more
explicit when we want to do this work.

Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-01-07 14:18:24 +01:00
Josef Bacik
462b728ea8 btrfs: only call inode_sub_bytes in truncate paths that care
We currently have a bunch of awkward checks to make sure we only update
the inode i_bytes if we're truncating the real inode.  Instead keep
track of the number of bytes we need to sub in the
btrfs_truncate_control, and then do the appropriate adjustment in the
truncate paths that care.

Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-01-07 14:18:24 +01:00
Josef Bacik
c2ddb612a8 btrfs: only update i_size in truncate paths that care
We currently will update the i_size of the inode as we truncate it down,
however we skip this if we're calling btrfs_truncate_inode_items from
the tree log code.  However we also don't care about this in the case of
evict.  Instead keep track of this value in the btrfs_truncate_control
and then have btrfs_truncate() and the free space cache truncate path
both do the i_size update themselves.

Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-01-07 14:18:24 +01:00
Josef Bacik
d9ac19c380 btrfs: add truncate control struct
I'm going to be adding more arguments and counters to
btrfs_truncate_inode_items, so add a control struct to handle all of the
extra arguments to make it easier to follow.

Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-01-07 14:18:24 +01:00
Josef Bacik
2adc75d612 btrfs: move btrfs_kill_delayed_inode_items into evict
We have a special case in btrfs_truncate_inode_items() to call
btrfs_kill_delayed_inode_items() if min_type == 0, which is only called
during evict.

Instead move this out into evict proper, and add some comments because I
erroneously attempted to remove this code altogether without
understanding what we were doing.

Evict is updating the inode only because we only care about making sure
the i_nlink count has hit disk.  If we had pending deletions we don't
want to process those via the delayed inode updates, we simply want to
drop all of them and reclaim the reserved metadata space.  Then from
there the btrfs_truncate_inode_items() will do the work to remove all of
the items as appropriate.

Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-01-07 14:18:24 +01:00
Josef Bacik
9a4a1429ac btrfs: move extent locking outside of btrfs_truncate_inode_items
Currently we are locking the extent and dropping the extent cache for
any inodes we truncate, unless they're in the tree log.  We call this
helper from:

- truncate
- evict
- tree log
- free space cache truncation

For evict we've already dropped all of the extent cache for this inode
once we've gotten here, and we're the only one accessing this inode, so
this step is unnecessary.

For the tree log code we already skip this part.

Pull this work into the truncate path and the free space cache
truncation path.

Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-01-07 14:18:24 +01:00
Josef Bacik
54f03ab1e1 btrfs: move btrfs_truncate_inode_items to inode-item.c
This is an inode item related manipulation with a few vfs related
adjustments.  I'm going to remove the vfs related code from this helper
and simplify it a lot, but I want those changes to be easily seen via
git blame, so move this function now and then the simplification work
can be done.

Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-01-07 14:18:24 +01:00
Josef Bacik
26c2c4540d btrfs: add an inode-item.h
We have a few helpers in inode-item.c, and I'm going to make a few
changes to how we do truncate in the future, so break out these
definitions into their own header file to trim down ctree.h some and
make it easier to do the work on truncate in the future.

Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-01-07 14:18:23 +01:00
Josef Bacik
fc28b25e1f btrfs: stop accessing ->csum_root directly
We are going to have multiple csum roots in the future, so convert all
users of ->csum_root to btrfs_csum_root() and rename ->csum_root to
->_csum_root so we can easily find remaining users in the future.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-01-03 15:09:49 +01:00
Josef Bacik
056c831116 btrfs: set BTRFS_FS_STATE_NO_CSUMS if we fail to load the csum root
We have a few places where we skip doing csums if we mounted with one of
the rescue options that ignores bad csum roots.  In the future when
there are multiple csum roots it'll be costly to check and see if there
are any missing csum roots, so simply add a flag to indicate the fs
should skip loading csums in case of errors.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-01-03 15:09:49 +01:00
Josef Bacik
9270501c16 btrfs: change root to fs_info for btrfs_reserve_metadata_bytes
We used to need the root for btrfs_reserve_metadata_bytes to check the
orphan cleanup state, but we no longer need that, we simply need the
fs_info.  Change btrfs_reserve_metadata_bytes() to use the fs_info, and
change both btrfs_block_rsv_refill() and btrfs_block_rsv_add() to do the
same as they simply call btrfs_reserve_metadata_bytes() and then
manipulate the block_rsv that is being used.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-01-03 15:09:45 +01:00
Josef Bacik
54230013d4 btrfs: get rid of root->orphan_cleanup_state
Now that we don't care about the stage of the orphan_cleanup_state,
simply replace it with a bit on ->state to make sure we don't call the
orphan cleanup every time we wander into this root.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-01-03 15:09:45 +01:00
Josef Bacik
ee6adbfd6a btrfs: make BTRFS_RESERVE_FLUSH_EVICT use the global rsv stealing code
I forgot to convert this over when I introduced the global reserve
stealing code to the space flushing code.  Evict was simply trying to
make its reservation and then if it failed it would steal from the
global rsv, which is racey because it's outside of the normal ticketing
code.

Fix this by setting ticket->steal if we are BTRFS_RESERVE_FLUSH_EVICT,
and then make the priority flushing path do the steal for us.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-01-03 15:09:45 +01:00
Josef Bacik
437bd07e6c btrfs: make btrfs_file_extent_inline_item_len take a slot
Instead of getting the btrfs_item for this, simply pass in the slot of
the item and then use the btrfs_item_size_nr() helper inside of
btrfs_file_extent_inline_item_len().

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-01-03 15:09:43 +01:00
Filipe Manana
f0bfa76a11 btrfs: fix ENOSPC failure when attempting direct IO write into NOCOW range
When doing a direct IO write against a file range that either has
preallocated extents in that range or has regular extents and the file
has the NOCOW attribute set, the write fails with -ENOSPC when all of
the following conditions are met:

1) There are no data blocks groups with enough free space matching
   the size of the write;

2) There's not enough unallocated space for allocating a new data block
   group;

3) The extents in the target file range are not shared, neither through
   snapshots nor through reflinks.

This is wrong because a NOCOW write can be done in such case, and in fact
it's possible to do it using a buffered IO write, since when failing to
allocate data space, the buffered IO path checks if a NOCOW write is
possible.

The failure in direct IO write path comes from the fact that early on,
at btrfs_dio_iomap_begin(), we try to allocate data space for the write
and if it that fails we return the error and stop - we never check if we
can do NOCOW. But later, at btrfs_get_blocks_direct_write(), we check
if we can do a NOCOW write into the range, or a subset of the range, and
then release the previously reserved data space.

Fix this by doing the data reservation only if needed, when we must COW,
at btrfs_get_blocks_direct_write() instead of doing it at
btrfs_dio_iomap_begin(). This also simplifies a bit the logic and removes
the inneficiency of doing unnecessary data reservations.

The following example test script reproduces the problem:

  $ cat dio-nocow-enospc.sh
  #!/bin/bash

  DEV=/dev/sdj
  MNT=/mnt/sdj

  # Use a small fixed size (1G) filesystem so that it's quick to fill
  # it up.
  # Make sure the mixed block groups feature is not enabled because we
  # later want to not have more space available for allocating data
  # extents but still have enough metadata space free for the file writes.
  mkfs.btrfs -f -b $((1024 * 1024 * 1024)) -O ^mixed-bg $DEV
  mount $DEV $MNT

  # Create our test file with the NOCOW attribute set.
  touch $MNT/foobar
  chattr +C $MNT/foobar

  # Now fill in all unallocated space with data for our test file.
  # This will allocate a data block group that will be full and leave
  # no (or a very small amount of) unallocated space in the device, so
  # that it will not be possible to allocate a new block group later.
  echo
  echo "Creating test file with initial data..."
  xfs_io -c "pwrite -S 0xab -b 1M 0 900M" $MNT/foobar

  # Now try a direct IO write against file range [0, 10M[.
  # This should succeed since this is a NOCOW file and an extent for the
  # range was previously allocated.
  echo
  echo "Trying direct IO write over allocated space..."
  xfs_io -d -c "pwrite -S 0xcd -b 10M 0 10M" $MNT/foobar

  umount $MNT

When running the test:

  $ ./dio-nocow-enospc.sh
  (...)

  Creating test file with initial data...
  wrote 943718400/943718400 bytes at offset 0
  900 MiB, 900 ops; 0:00:01.43 (625.526 MiB/sec and 625.5265 ops/sec)

  Trying direct IO write over allocated space...
  pwrite: No space left on device

A test case for fstests will follow, testing both this direct IO write
scenario as well as the buffered IO write scenario to make it less likely
to get future regressions on the buffered IO case.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-01-03 15:09:41 +01:00
Linus Torvalds
037c50bfbe for-5.16-tag
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEE8rQSAMVO+zA4DBdWxWXV+ddtWDsFAmF/7PAACgkQxWXV+ddt
 WDtp6A//SbVYeuHWpsXkhBiOpJt2PpS1K8VY5LIJc3brua5EZm8IarlR57X9IqYu
 89ZlWnuANrw4d5RRiIO+NYhc+DR6+ydxHesJG+I2B+o5OnR0Ynb06gLhsP1tSK6y
 lYZORQFJZP051ODU/uEc8A0KZN7DySIUmqezAibfyxepF6oPEap0nFp17/B80tWp
 sKdMp2TBN5ymZwsdSK1nZ7ws1ZL57HgkFDPqp8m8CuPTkneG4CtNol6yUpuPExpL
 QzvQsqTygmiFoy0uNTG7Rg7IlKqEuhbR7lwfkmcBZCV66JmhFco5QhxN13QIn42s
 +YSug52SMWc8YVHIEj16xtBgHEqZXWYey8d2ewhc0tDSGDm0HmXCNjcn1vYr0NJr
 5bW/7/3bpkHYejasy1wDEK5P8Uo2xsgpRyAvuEReGoRi8ze66EohahvP3o7YJi/Q
 o0pROXdCT89JbM/T4MTvN/5MUlCSM7rnexXZ39ldGNacPgn9FAUCPw6KtzKKyVRe
 DF19nPOUXSg6SLECbVkRQUwcOjxOTFP+T0Jx61Um8bomFskYJJnmr4SD3pqlzgp7
 NxV5ad0+r7zU0x9MADkyqboObo0ROAfD4hthcZiRN+0UIK+Gq5nATTD5ur6/nwsT
 0PJGOXDPz7cmfqUdmvpA0ctRxbFEqpaz6sDh7nq/iUSmaGITcUM=
 =HvYu
 -----END PGP SIGNATURE-----

Merge tag 'for-5.16-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs updates from David Sterba:
 "The updates this time are more under the hood and enhancing existing
  features (subpage with compression and zoned namespaces).

  Performance related:

   - misc small inode logging improvements (+3% throughput, -11% latency
     on sample dbench workload)

   - more efficient directory logging: bulk item insertion, less tree
     searches and locking

   - speed up bulk insertion of items into a b-tree, which is used when
     logging directories, when running delayed items for directories
     (fsync and transaction commits) and when running the slow path
     (full sync) of an fsync (bulk creation run time -4%, deletion -12%)

  Core:

   - continued subpage support
      - make defragmentation work
      - make compression write work

   - zoned mode
      - support ZNS (zoned namespaces), zone capacity is number of
        usable blocks in each zone
      - add dedicated block group (zoned) for relocation, to prevent
        out of order writes in some cases
      - greedy block group reclaim, pick the ones with least usable
        space first

   - preparatory work for send protocol updates

   - error handling improvements

   - cleanups and refactoring

  Fixes:

   - lockdep warnings
      - in show_devname callback, on seeding device
      - device delete on loop device due to conversions to workqueues

   - fix deadlock between chunk allocation and chunk btree modifications

   - fix tracking of missing device count and status"

* tag 'for-5.16-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: (140 commits)
  btrfs: remove root argument from check_item_in_log()
  btrfs: remove root argument from add_link()
  btrfs: remove root argument from btrfs_unlink_inode()
  btrfs: remove root argument from drop_one_dir_item()
  btrfs: clear MISSING device status bit in btrfs_close_one_device
  btrfs: call btrfs_check_rw_degradable only if there is a missing device
  btrfs: send: prepare for v2 protocol
  btrfs: fix comment about sector sizes supported in 64K systems
  btrfs: update device path inode time instead of bd_inode
  fs: export an inode_update_time helper
  btrfs: fix deadlock when defragging transparent huge pages
  btrfs: sysfs: convert scnprintf and snprintf to sysfs_emit
  btrfs: make btrfs_super_block size match BTRFS_SUPER_INFO_SIZE
  btrfs: update comments for chunk allocation -ENOSPC cases
  btrfs: fix deadlock between chunk allocation and chunk btree modifications
  btrfs: zoned: use greedy gc for auto reclaim
  btrfs: check-integrity: stop storing the block device name in btrfsic_dev_state
  btrfs: use btrfs_get_dev_args_from_path in dev removal ioctls
  btrfs: add a btrfs_get_dev_args_from_path helper
  btrfs: handle device lookup with btrfs_dev_lookup_args
  ...
2021-11-01 12:48:25 -07:00
Linus Torvalds
33c8846c81 for-5.16/block-2021-10-29
-----BEGIN PGP SIGNATURE-----
 
 iQJEBAABCAAuFiEEwPw5LcreJtl1+l5K99NY+ylx4KYFAmF8KDgQHGF4Ym9lQGtl
 cm5lbC5kawAKCRD301j7KXHgpmQ2D/wO0nH3U+3+OZChi3XUwYck9Dev3o6BANCF
 ClATiK/kivZY0xY1r8J4ixirZo2gcjIMpWSC3JGYZ5LdspfmYGLUbMjfZsaeU23i
 lAKaX1IqfArmHN76k3IU1bKCg7B0/LFwC0q9QTFWTSwNSs8RK/EZLJ61U1hEXUb3
 OfIpaMmvPiMaU7yuPqhcZK14m1cg1srrLM4rFB/PqsWWStF07pHq32WeArGDAU0e
 Fe0YSnYD7qqA5Qc37KwqjCTmmxKX5YZf7etIcA6p3DNmwcuQrVNzKoCH/ZEDijaD
 E2bS/BWbN1x96+rtoEZfBYEaNIrkmJzmW6+fJ53OITbJF3KqP6V66erhqNcFYCzC
 mhFlRe7voXb/8AP7zQqSIhK529BUBM36sQ6nF7EiQcDrfLc1z39mq6eblUxbknIA
 DDPISD5Tseik9N9x0bc7vINseKyHI1E90VAU/XKADcuGbzLvehPx+2p+Iq5ch5Ah
 oa1G3RdlWWQOZxphJHWJhu1qMfo5+FP9dFZj1aoo7b8Kbc/CedyoQe71cpIE5wNh
 Jj/EpWJnuyKXwuTic2VYGC+6ezM9O5DSdqCfP3YuZky95VESyvRCKJYMMgBYRVdC
 /LuxhnBXIY2G8An7ZTnX0kLCCvLbapIwa0NyA98/xeOngO843coJ6wn8ZmE9LJNH
 kMmpCygUrA==
 =QWC+
 -----END PGP SIGNATURE-----

Merge tag 'for-5.16/block-2021-10-29' of git://git.kernel.dk/linux-block

Pull block updates from Jens Axboe:

 - mq-deadline accounting improvements (Bart)

 - blk-wbt timer fix (Andrea)

 - Untangle the block layer includes (Christoph)

 - Rework the poll support to be bio based, which will enable adding
   support for polling for bio based drivers (Christoph)

 - Block layer core support for multi-actuator drives (Damien)

 - blk-crypto improvements (Eric)

 - Batched tag allocation support (me)

 - Request completion batching support (me)

 - Plugging improvements (me)

 - Shared tag set improvements (John)

 - Concurrent queue quiesce support (Ming)

 - Cache bdev in ->private_data for block devices (Pavel)

 - bdev dio improvements (Pavel)

 - Block device invalidation and block size improvements (Xie)

 - Various cleanups, fixes, and improvements (Christoph, Jackie,
   Masahira, Tejun, Yu, Pavel, Zheng, me)

* tag 'for-5.16/block-2021-10-29' of git://git.kernel.dk/linux-block: (174 commits)
  blk-mq-debugfs: Show active requests per queue for shared tags
  block: improve readability of blk_mq_end_request_batch()
  virtio-blk: Use blk_validate_block_size() to validate block size
  loop: Use blk_validate_block_size() to validate block size
  nbd: Use blk_validate_block_size() to validate block size
  block: Add a helper to validate the block size
  block: re-flow blk_mq_rq_ctx_init()
  block: prefetch request to be initialized
  block: pass in blk_mq_tags to blk_mq_rq_ctx_init()
  block: add rq_flags to struct blk_mq_alloc_data
  block: add async version of bio_set_polled
  block: kill DIO_MULTI_BIO
  block: kill unused polling bits in __blkdev_direct_IO()
  block: avoid extra iter advance with async iocb
  block: Add independent access ranges support
  blk-mq: don't issue request directly in case that current is to be blocked
  sbitmap: silence data race warning
  blk-cgroup: synchronize blkg creation against policy deactivation
  block: refactor bio_iov_bvec_set()
  block: add single bio async direct IO helper
  ...
2021-11-01 09:19:50 -07:00
Linus Torvalds
fd919bbd33 for-5.15-rc7-tag
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEE8rQSAMVO+zA4DBdWxWXV+ddtWDsFAmF72q0ACgkQxWXV+ddt
 WDvFOxAAkcryx2FP5aqaoMzBKfoCtMFHO3uAvm+rsMcglWe5kaXhBnHa2HPzoyEh
 YqEx2TeXMTuA2I15bU8KV1RMhQzzRjC4NhdRqY6uaKAcKgON6sJlK5qsq2BnB+V3
 nrue1jppM2Vv8wNzjMNeVETQNC7pmg29yQP/fvWaB36Yar2tyfyWDF11e42HR7cU
 yLQUedg30WEayz3Mp6MTBF36h09WXQrZSs7Iwk1JMQbpxWcpn2CjXrO+vIZOMdvH
 XZZsxBTNB8GJIaJlXssgsq3OP2wspK1lrVHNfi5PYtcZEaFrhkPaVB6enDfd41YV
 zXwj1dnemCni9fh88gZprel9bLyB37dSVfIqq2Ly3hQbSAN4dmHIpxGwPSRIr+Hl
 Bn3UfClHpAftbpd/Y77U7GgcYnkuRo3Bd4mGTF3ZuPDLVrf/QX5BlfGa2dmJYoml
 NfBit7Ha4UrxLW6C8RC6fyEbLQxpNYFY55Ra0Tj0BBO/uhWiqtQGZwC/qbyPKfzN
 YZFcPR6iTILoCHXNan3iZIuLeASMT0djgAtunXXf/BuFnxGfnOuqL3bKt2vojh3+
 rsqpeIxSP/VklKv4JcP3axeLmUK6cA8/9dV2ES0M0Fc0o341jfh+AoVw0GleFeus
 gXlDFPRJeE8yyXmjKyW4shctOczqoeMIq3umebXPP9R4jd/LU/g=
 =YWGa
 -----END PGP SIGNATURE-----

Merge tag 'for-5.15-rc7-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs fixes from David Sterba:
 "Last minute fixes for crash on 32bit architectures when compression is
  in use. It's a regression introduced in 5.15-rc and I'd really like
  not let this into the final release, fixes via stable trees would add
  unnecessary delay.

  The problem is on 32bit architectures with highmem enabled, the pages
  for compression may need to be kmapped, while the patches removed that
  as we don't use GFP_HIGHMEM allocations anymore. The pages that don't
  come from local allocation still may be from highmem. Despite being on
  32bit there's enough such ARM machines in use so it's not a marginal
  issue.

  I did full reverts of the patches one by one instead of a huge one.
  There's one exception for the "lzo" revert as there was an
  intermediate patch touching the same code to make it compatible with
  subpage. I can't revert that one too, so the revert in lzo.c is
  manual. Qu Wenruo has worked on that with me and verified the changes"

* tag 'for-5.15-rc7-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  Revert "btrfs: compression: drop kmap/kunmap from lzo"
  Revert "btrfs: compression: drop kmap/kunmap from zlib"
  Revert "btrfs: compression: drop kmap/kunmap from zstd"
  Revert "btrfs: compression: drop kmap/kunmap from generic helpers"
2021-10-29 10:46:59 -07:00
Filipe Manana
4467af8809 btrfs: remove root argument from btrfs_unlink_inode()
The root argument passed to btrfs_unlink_inode() and its callee,
__btrfs_unlink_inode(), always matches the root of the given directory and
the given inode. So remove the argument and make __btrfs_unlink_inode()
use the root of the directory.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-10-29 12:39:13 +02:00
David Sterba
3a60f6537c Revert "btrfs: compression: drop kmap/kunmap from generic helpers"
This reverts commit 4c2bf276b5.

The kmaps in compression code are still needed and cause crashes on
32bit machines (ARM, x86). Reproducible eg. by running fstest btrfs/004
with enabled LZO or ZSTD compression.

Link: https://lore.kernel.org/all/CAJCQCtT+OuemovPO7GZk8Y8=qtOObr0XTDp8jh4OHD6y84AFxw@mail.gmail.com/
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=214839
Signed-off-by: David Sterba <dsterba@suse.com>
2021-10-27 10:39:03 +02:00
Qu Wenruo
f4f39fc5dc btrfs: remove btrfs_bio::logical member
The member btrfs_bio::logical is only initialized by two call sites:

- btrfs_repair_one_sector()
  No corresponding site to utilize it.

- btrfs_submit_direct()
  The corresponding site to utilize it is btrfs_check_read_dio_bio().

However for btrfs_check_read_dio_bio(), we can grab the file_offset from
btrfs_dio_private::file_offset directly.

Thus it turns out we don't really need that btrfs_bio::logical member at
all.

For btrfs_bio, the logical bytenr can be fetched from its
bio->bi_iter.bi_sector directly.

So let's just remove the member to save 8 bytes for structure btrfs_bio.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-10-26 19:08:06 +02:00
Qu Wenruo
47926ab535 btrfs: rename btrfs_dio_private::logical_offset to file_offset
The naming of "logical_offset" can be confused with logical bytenr of
the dio range.

In fact it's file offset, and the naming "file_offset" is already widely
used in all other sites.

Just do the rename to avoid confusion.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-10-26 19:08:06 +02:00
Nikolay Borisov
681145d4ac btrfs: pull up qgroup checks from delayed-ref core to init time
Instead of checking whether qgroup processing for a dealyed ref has to
happen in the core of delayed ref, simply pull the check at init time of
respective delayed ref structures. This eliminates the final use of
real_root in delayed-ref core paving the way to making this member
optional.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-10-26 19:08:06 +02:00
Nikolay Borisov
f42c5da6c1 btrfs: add additional parameters to btrfs_init_tree_ref/btrfs_init_data_ref
In order to make 'real_root' used only in ref-verify it's required to
have the necessary context to perform the same checks that this member
is used for. So add 'mod_root' which will contain the root on behalf of
which a delayed ref was created and a 'skip_group' parameter which
will contain callsite-specific override of skip_qgroup.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-10-26 19:08:06 +02:00
Josef Bacik
8496153945 btrfs: add a BTRFS_FS_ERROR helper
We have a few flags that are inconsistently used to describe the fs in
different states of failure.  As of 5963ffcaf3 ("btrfs: always abort
the transaction if we abort a trans handle") we will always set
BTRFS_FS_STATE_ERROR if we abort, so we don't have to check both ABORTED
and ERROR to see if things have gone wrong.  Add a helper to check
BTRFS_FS_STATE_ERROR and then convert all checkers of FS_STATE_ERROR to
use the helper.

The TRANS_ABORTED bit check was added in af72273381 ("Btrfs: clean up
resources during umount after trans is aborted") but is not actually
specific.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-10-26 19:08:05 +02:00
Josef Bacik
9a35fc9542 btrfs: change error handling for btrfs_delete_*_in_log
Currently we will abort the transaction if we get a random error (like
-EIO) while trying to remove the directory entries from the root log
during rename.

However since these are simply log tree related errors, we can mark the
trans as needing a full commit.  Then if the error was truly
catastrophic we'll hit it during the normal commit and abort as
appropriate.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-10-26 19:08:05 +02:00
Qu Wenruo
0cf9b244e7 btrfs: subpage: only allow compression if the range is fully page aligned
For compressed write, we use a mechanism called async COW, which unlike
regular run_delalloc_cow() or cow_file_range() will also unlock the
first page.

This mechanism allows us to continue handling next ranges, without
waiting for the time consuming compression.

But this has a problem for subpage case, as we could have the following
delalloc range for a page:

0		32K		64K
|	|///////|	|///////|
		\- A		\- B

In the above case, if we pass both ranges to cow_file_range_async(),
both range A and range B will try to unlock the full page [0, 64K).

And which one finishes later than the other one will try to do other
page operations like end_page_writeback() on a unlocked page, triggering
VM layer BUG_ON().

To make subpage compression work at least partially, here we add another
restriction for it, only allow compression if the delalloc range is
fully page aligned.

By that, async extent is always ensured to unlock the first page
exclusively, just like it used to be for regular sectorsize.

In theory, we only need to make sure the delalloc range fully covers its
first page, but the tail page will be locked anyway, blocking later
writeback until the compression finishes.

Thus here we choose to make sure the range is fully page aligned before
doing the compression.

In the future, we could optimize the situation by properly increasing
subpage::writers number for the locked page, but that also means we need
to change how we run delalloc range of page.
(Instead of running each delalloc range we hit, we need to find and lock
all delalloc ranges covering the page, then run each of them).

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-10-26 19:08:05 +02:00
Qu Wenruo
2749f7ef36 btrfs: subpage: avoid potential deadlock with compression and delalloc
[BUG]
With experimental subpage compression enabled, a simple fsstress can
lead to self deadlock on page 720896:

        mkfs.btrfs -f -s 4k $dev > /dev/null
        mount $dev -o compress $mnt
        $fsstress -p 1 -n 100 -w -d $mnt -v -s 1625511156

[CAUSE]
If we have a file layout looks like below:

	0	32K	64K	96K	128K
	|//|		|///////////////|
	   4K

Then we run delalloc range for the inode, it will:

- Call find_lock_delalloc_range() with @delalloc_start = 0
  Then we got a delalloc range [0, 4K).

  This range will be COWed.

- Call find_lock_delalloc_range() again with @delalloc_start = 4K
  Since find_lock_delalloc_range() never cares whether the range
  is still inside page range [0, 64K), it will return range [64K, 128K).

  This range meets the condition for subpage compression, will go
  through async COW path.

  And async COW path will return @page_started.

  But that @page_started is now for range [64K, 128K), not for range
  [0, 64K).

- writepage_dellloc() returned 1 for page [0, 64K)
  Thus page [0, 64K) will not be unlocked, nor its page dirty status
  will be cleared.

Next time when we try to lock page [0, 64K) we will deadlock, as there
is no one to release page [0, 64K).

This problem will never happen for regular page size as one page only
contains one sector.  After the first find_lock_delalloc_range() call,
the @delalloc_end will go beyond @page_end no matter if we found a
delalloc range or not

Thus this bug only happens for subpage, as now we need multiple runs to
exhaust the delalloc range of a page.

[FIX]
Fix the problem by ensuring the delalloc range we ran at least started
inside @locked_page.

So that we will never get incorrect @page_started.

And to prevent such problem from happening again:

- Make find_lock_delalloc_range() return false if the found range is
  beyond @end value passed in.

  Since @end will be utilized now, add an ASSERT() to ensure we pass
  correct @end into find_lock_delalloc_range().

  This also means, for selftests we needs to populate @end before calling
  find_lock_delalloc_range().

- New ASSERT() in find_lock_delalloc_range()
  Now we will make sure the @start/@end passed in at least covers part
  of the page.

- New ASSERT() in run_delalloc_range()
  To make sure the range at least starts inside @locked page.

- Use @delalloc_start as proper cursor, while @delalloc_end is always
  reset to @page_end.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-10-26 19:08:05 +02:00
Qu Wenruo
2b83a0eea5 btrfs: factor uncompressed async extent submission code into a new helper
Introduce a new helper, submit_uncompressed_range(), for async cow cases
where we fallback to COW.

There are some new updates introduced to the helper:

- Proper locked_page detection
  It's possible that the async_extent range doesn't cover the locked
  page.  In that case we shouldn't unlock the locked page.

  In the new helper, we will ensure that we only unlock the locked page
  when:

  * The locked page covers part of the async_extent range
  * The locked page is not unlocked by cow_file_range() nor
    extent_write_locked_range()

  This also means extra comments are added focusing on the page locking.

- Add extra comment on some rare parameter used.
  We use @unlock_page = 0 for cow_file_range(), where only two call
  sites doing the same thing, including the new helper.

  It's definitely worth some comments.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-10-26 19:08:05 +02:00
Qu Wenruo
4c162778d6 btrfs: subpage: make compress_file_range() compatible
In function compress_file_range(), when the compression is finished, the
function just rounds up @total_in to PAGE_SIZE.  This is fine for
regular sectorsize == PAGE_SIZE case, but not for subpage.

Just change the ALIGN(, PAGE_SIZE) to round_up(, sectorsize) so that
both regular sectorsize and subpage sectorsize will be happy.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-10-26 19:08:04 +02:00
Qu Wenruo
2bd0fc9349 btrfs: cleanup for extent_write_locked_range()
There are several cleanups for extent_write_locked_range(), most of them
are pure cleanups, but with some preparation for future subpage support.

- Add a proper comment for which call sites are suitable
  Unlike regular synchronized extent write back, if async COW or zoned
  COW happens, we have all pages in the range still locked.

  Thus for those (only) two call sites, we need this function to submit
  page content into bios and submit them.

- Remove @mode parameter
  All the existing two call sites pass WB_SYNC_ALL. No need for @mode
  parameter.

- Better error handling
  Currently if we hit an error during the page iteration loop, we
  overwrite @ret, causing only the last error can be recorded.

  Here we add @found_error and @first_error variable to record if we hit
  any error, and the first error we hit.
  So the first error won't get lost.

- Don't reuse @start as the cursor
  We reuse the parameter @start as the cursor to iterate the range, not
  a big problem, but since we're here, introduce a proper @cur as the
  cursor.

- Remove impossible branch
  Since all pages are still locked after the ordered extent is inserted,
  there is no way that pages can get its dirty bit cleared.
  Remove the branch where page is not dirty and replace it with an
  ASSERT().

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-10-26 19:08:04 +02:00
Qu Wenruo
b4ccace878 btrfs: refactor submit_compressed_extents()
We have a big chunk of code inside a while() loop, with tons of strange
jumps for error handling.  It's definitely not to the code standard of
today.  Move the code into a new function, submit_one_async_extent().

Since we're here, also do the following changes:

- Comment style change
  To follow the current scheme

- Don't fallback to non-compressed write then hitting ENOSPC
  If we hit ENOSPC for compressed write, how could we reserve more space
  for non-compressed write?
  Thus we go error path directly.
  This removes the retry: label.

- Add more comment for super long parameter list
  Explain which parameter is for, so we don't need to check the
  prototype.

- Move the error handling to submit_one_async_extent()
  Thus no strange code like:

  out_free:
	...
	goto again;

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-10-26 19:08:04 +02:00
Qu Wenruo
6aabd85835 btrfs: remove unused function btrfs_bio_fits_in_stripe()
As the last caller in compression.c has been removed, we don't need that
function anymore.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-10-26 19:08:04 +02:00
Qu Wenruo
e4f9434749 btrfs: subpage: add bitmap for PageChecked flag
Although in btrfs we have very limited usage of PageChecked flag, it's
still some page flag not yet subpage compatible.

Fix it by introducing btrfs_subpage::checked_offset to do the convert.

For most call sites, especially for free-space cache, COW fixup and
btrfs_invalidatepage(), they all work in full page mode anyway.

For other call sites, they work as subpage compatible mode.

Some call sites need extra modification:

- btrfs_drop_pages()
  Needs extra parameter to get the real range we need to clear checked
  flag.

  Also since btrfs_drop_pages() will accept pages beyond the dirtied
  range, update btrfs_subpage_clamp_range() to handle such case
  by setting @len to 0 if the page is beyond target range.

- btrfs_invalidatepage()
  We need to call subpage helper before calling __btrfs_releasepage(),
  or it will trigger ASSERT() as page->private will be cleared.

- btrfs_verify_data_csum()
  In theory we don't need the io_bio->csum check anymore, but it's
  won't hurt.  Just change the comment.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-10-26 19:08:03 +02:00
Qu Wenruo
584691748c btrfs: don't pass compressed pages to btrfs_writepage_endio_finish_ordered()
Since async_extent holds the compressed page, it would trigger the new
ASSERT() in btrfs_mark_ordered_io_finished() which checks that the range
is inside the page.

Now btrfs_writepage_endio_finish_ordered() can accept @page == NULL,
just pass NULL to btrfs_writepage_endio_finish_ordered().

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-10-26 19:08:03 +02:00
Qu Wenruo
9e895a8f7e btrfs: use async_chunk::async_cow to replace the confusing pending pointer
For structure async_chunk, we use a very strange member layout to grab
structure async_cow who owns this async_chunk.

At initialization, it goes like this:

		async_chunk[i].pending = &ctx->num_chunks;

Then at async_cow_free() we do a super weird freeing:

	/*
	 * Since the pointer to 'pending' is at the beginning of the array of
	 * async_chunk's, freeing it ensures the whole array has been freed.
	 */
	if (atomic_dec_and_test(async_chunk->pending))
		kvfree(async_chunk->pending);

This is absolutely an abuse of kvfree().

Replace async_chunk::pending with async_chunk::async_cow, so that we can
grab the async_cow structure directly, without this strange dancing.

And with this change, there is no requirement for any specific member
location.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-10-26 19:08:03 +02:00
Filipe Manana
b7ef5f3a6f btrfs: loop only once over data sizes array when inserting an item batch
When inserting a batch of items into a btree, we end up looping over the
data sizes array 3 times:

1) Once in the caller of btrfs_insert_empty_items(), when it populates the
   array with the data sizes for each item;

2) Once at btrfs_insert_empty_items() to sum the elements of the data
   sizes array and compute the total data size;

3) And then once again at setup_items_for_insert(), where we do exactly
   the same as what we do at btrfs_insert_empty_items(), to compute the
   total data size.

That is not bad for small arrays, but when the arrays have hundreds of
elements, the time spent on looping is not negligible. For example when
doing batch inserts of delayed items for dir index items or when logging
a directory, it's common to have 200 to 260 dir index items in a single
batch when using a leaf size of 16K and using file names between 8 and 12
characters. For a 64K leaf size, multiply that by 4. Taking into account
that during directory logging or when flushing delayed dir index items we
can have many of those large batches, the time spent on the looping adds
up quickly.

It's also more important to avoid it at setup_items_for_insert(), since
we are holding a write lock on a leaf and, in some cases, on upper nodes
of the btree, which causes us to block other tasks that want to access
the leaf and nodes for longer than necessary.

So change the code so that setup_items_for_insert() and
btrfs_insert_empty_items() no longer compute the total data size, and
instead rely on the caller to supply it. This makes us loop over the
array only once, where we can both populate the data size array and
compute the total data size, taking advantage of spatial and temporal
locality. To make this more manageable, use a structure to contain
all the relevant details for a batch of items (keys array, data sizes
array, total data size, number of items), and use it as an argument
for btrfs_insert_empty_items() and setup_items_for_insert().

This patch is part of a small patchset that is comprised of the following
patches:

  btrfs: loop only once over data sizes array when inserting an item batch
  btrfs: unexport setup_items_for_insert()
  btrfs: use single bulk copy operations when logging directories

This is patch 1/3 and performance results, and the specific tests, are
included in the changelog of patch 3/3.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-10-26 19:08:03 +02:00
Qu Wenruo
c3a3b19bac btrfs: rename struct btrfs_io_bio to btrfs_bio
Previously we had "struct btrfs_bio", which records IO context for
mirrored IO and RAID56, and "strcut btrfs_io_bio", which records extra
btrfs specific info for logical bytenr bio.

With "btrfs_bio" renamed to "btrfs_io_context", we are safe to rename
"btrfs_io_bio" to "btrfs_bio" which is a more suitable name now.

The struct btrfs_bio changes meaning by this commit. There was a
suggested name like btrfs_logical_bio but it's a bit long and we'd
prefer to use a shorter name.

This could be a concern for backports to older kernels where the
different meaning could possibly cause confusion or bugs. Comparing the
new and old structures, there's no overlap among the struct members so a
build would break in case of incorrect backport.

We haven't had many backports to bio code anyway so this is more of a
theoretical cause of bugs and a matter of precaution but we'll need to
keep the semantic change in mind.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-10-26 19:08:02 +02:00
Filipe Manana
dc2872247e btrfs: keep track of the last logged keys when logging a directory
After the first time we log a directory in the current transaction, for
each directory item in a changed leaf of the subvolume tree, we have to
check if we previously logged the item, in order to overwrite it in case
its data changed or skip it in case its data hasn't changed.

Checking if we have logged each item before not only wastes times, but it
also adds lock contention on the log tree. So in order to minimize the
number of times we do such checks, keep track of the offset of the last
key we logged for a directory and, on the next time we log the directory,
skip the checks for any new keys that have an offset greater than the
offset we have previously saved. This is specially effective for index
keys, because the offset for these keys comes from a monotonically
increasing counter.

This patch is part of a patchset comprised of the following 5 patches:

  btrfs: remove root argument from btrfs_log_inode() and its callees
  btrfs: remove redundant log root assignment from log_dir_items()
  btrfs: factor out the copying loop of dir items from log_dir_items()
  btrfs: insert items in batches when logging a directory when possible
  btrfs: keep track of the last logged keys when logging a directory

This is patch 5/5.

The following test was used on a non-debug kernel to measure the impact
it has on a directory fsync:

  $ cat test-dir-fsync.sh
  #!/bin/bash

  DEV=/dev/nvme0n1
  MNT=/mnt/nvme0n1

  NUM_NEW_FILES=100000
  NUM_FILE_DELETES=1000

  mkfs.btrfs -f $DEV
  mount -o ssd $DEV $MNT

  mkdir $MNT/testdir

  for ((i = 1; i <= $NUM_NEW_FILES; i++)); do
      echo -n > $MNT/testdir/file_$i
  done

  # fsync the directory, this will log the new dir items and the inodes
  # they point to, because these are new inodes.
  start=$(date +%s%N)
  xfs_io -c "fsync" $MNT/testdir
  end=$(date +%s%N)

  dur=$(( (end - start) / 1000000 ))
  echo "dir fsync took $dur ms after adding $NUM_NEW_FILES files"

  # sync to force transaction commit and wipeout the log.
  sync

  del_inc=$(( $NUM_NEW_FILES / $NUM_FILE_DELETES ))
  for ((i = 1; i <= $NUM_NEW_FILES; i += $del_inc)); do
      rm -f $MNT/testdir/file_$i
  done

  # fsync the directory, this will only log dir items, there are no
  # dentries pointing to new inodes.
  start=$(date +%s%N)
  xfs_io -c "fsync" $MNT/testdir
  end=$(date +%s%N)

  dur=$(( (end - start) / 1000000 ))
  echo "dir fsync took $dur ms after deleting $NUM_FILE_DELETES files"

  umount $MNT

Test results with NUM_NEW_FILES set to 100 000 and 1 000 000:

**** before patchset, 100 000 files, 1000 deletes ****

dir fsync took 848 ms after adding 100000 files
dir fsync took 175 ms after deleting 1000 files

**** after patchset, 100 000 files, 1000 deletes ****

dir fsync took 758 ms after adding 100000 files  (-11.2%)
dir fsync took 63 ms after deleting 1000 files   (-94.1%)

**** before patchset, 1 000 000 files, 1000 deletes ****

dir fsync took 9945 ms after adding 1000000 files
dir fsync took 473 ms after deleting 1000 files

**** after patchset, 1 000 000 files, 1000 deletes ****

dir fsync took 8677 ms after adding 1000000 files (-13.6%)
dir fsync took 146 ms after deleting 1000 files   (-105.6%)

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-10-26 19:08:02 +02:00
Johannes Thumshirn
2adada886b btrfs: check for relocation inodes on zoned btrfs in should_nocow
Prepare for allowing preallocation for relocation inodes.

Reviewed-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-10-26 19:08:01 +02:00
Johannes Thumshirn
37f00a6d2e btrfs: introduce btrfs_is_data_reloc_root
There are several places in our codebase where we check if a root is the
root of the data reloc tree and subsequent patches will introduce more.

Factor out the check into a small helper function instead of open coding
it multiple times.

Reviewed-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-10-26 19:08:01 +02:00
Anand Jain
d24fa5c1da btrfs: convert latest_bdev type to btrfs_device and rename
In preparation to fix a bug in btrfs_show_devname().

Convert fs_devices::latest_bdev type from struct block_device to struct
btrfs_device and, rename the member to fs_devices::latest_dev.
So that btrfs_show_devname() can use fs_devices::latest_dev::name.

Tested-by: Su Yue <l@damenly.su>
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-10-26 19:08:00 +02:00
Naohiro Aota
be1a1d7a5d btrfs: zoned: finish fully written block group
If we have written to the zone capacity, the device automatically
deactivates the zone. Sync up block group side (the active BG list and
zone_is_active flag) with it.

We need to do it both on data BGs and metadata BGs. On data side, we add a
hook to btrfs_finish_ordered_io(). On metadata side, we use
end_extent_buffer_writeback().

To reduce excess lookup of a block group, we mark the last extent buffer in
a block group with EXTENT_BUFFER_ZONE_FINISH flag. This cannot be done for
data (ordered_extent), because the address may change due to
REQ_OP_ZONE_APPEND.

Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-10-26 19:08:00 +02:00
Christoph Hellwig
3e08773c38 block: switch polling to be bio based
Replace the blk_poll interface that requires the caller to keep a queue
and cookie from the submissions with polling based on the bio.

Polling for the bio itself leads to a few advantages:

 - the cookie construction can made entirely private in blk-mq.c
 - the caller does not need to remember the request_queue and cookie
   separately and thus sidesteps their lifetime issues
 - keeping the device and the cookie inside the bio allows to trivially
   support polling BIOs remapping by stacking drivers
 - a lot of code to propagate the cookie back up the submission path can
   be removed entirely.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Mark Wunderlich <mark.wunderlich@intel.com>
Link: https://lore.kernel.org/r/20211012111226.760968-15-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-18 06:17:36 -06:00
Christoph Hellwig
348332e000 mm: don't include <linux/blk-cgroup.h> in <linux/writeback.h>
blk-cgroup.h pulls in blkdev.h and thus pretty much all the block
headers.  Break this dependency chain by turning wbc_blkcg_css into a
macro and dropping the blk-cgroup.h include.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20210920123328.1399408-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-18 06:17:01 -06:00
Linus Torvalds
0ee7c3e25d New code for 5.15:
- Simplify the bio_end_page usage in the buffered IO code.
  - Support reading inline data at nonzero offsets for erofs.
  - Fix some typos and bad grammar.
  - Convert kmap_atomic usage in the inline data read path.
  - Add some extra inline data input checking.
  - Fix a memory corruption bug stemming from iomap_swapfile_activate
    trying to activate more pages than mm was expecting.
  - Pass errnos through the page writeback code so that writeback errors
    are reported correctly instead of being munged to EIO.
  - Replace iomap_apply with a open-coded iterator loops to reduce the
    number of indirect calls by a third to a half.
  - Refactor the fsdax code to use iomap iterators instead of the
    open-coded iomap_apply code that it had before.
  - Format file range iomap tracepoint data in hexadecimal and
    standardize the names used in the pretty-print string.
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEEUzaAxoMeQq6m2jMV+H93GTRKtOsFAmEnwC0ACgkQ+H93GTRK
 tOtVOQ//Zu9ul2ZmPARMV8xyAfopnLpmggREOthFbPkDZ3z3ZgRpPxlbAvWEEKnj
 VDNLFNj204rDojuxP/YSdxgiawLod7dYfXIwwft8R8oI7MdgVQhpvimUi5bkz/Od
 X5pmFDe84INfFvEztOgC+sPk1RI/ToQLgrcIffWMWfF2iyVkNVMCD5MMe6LoH1la
 9GbVCfPx6Y2Nffaa8EuAEgaCo7FMPc81bvQG4qpeqXyX8qql/r5n4YENhkn3n4qa
 zI4F2lgqwbelFkamZOYNDjtLt13lb7Ze0PoFOpmTZUqlyybqhRxDvJ+OxZn8W6zH
 20pxWx/RCXhCp/sS6DRcYyf7WKoIfdGDkxed7aSuhJ+VKKtBtsjMoy7dh5IY5RJa
 8L1DMat6xtea8Glx04SF7Vib0n/An9oHOTzLEWxsUlRaPhW68uVpKgXuGLTAf+dc
 ztJhlQ9pLX0D2NmgGlkXN8d4F1XEH2BgyIrtF6UNtMbyIlCREHM9HELJs6JzKl6U
 a4ivJXyaq8o/hlXr8IMWUOTVubS0i+hgvvQjnVJmcSTJxhH10mPPJLnNsGX6heD9
 SlnnXRbD03iqsbMJP/R431VKooryOSKBc86IEECkuMz3RUfw75DGAnLtETnT1rsA
 71rSVf5NaCGZ2hV4du6jv53TS7yrPpqkxJHyDWD1WP4xGPbO1XA=
 =iVns
 -----END PGP SIGNATURE-----

Merge tag 'iomap-5.15-merge-4' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux

Pull iomap updates from Darrick Wong:
 "The most notable externally visible change for this cycle is the
  addition of support for reads to inline tail fragments of files, which
  was requested by the erofs developers; and a correction for a kernel
  memory corruption bug if the sysadmin tries to activate a swapfile
  with more pages than the swapfile header suggests.

  We also now report writeback completion errors to the file mapping
  correctly, instead of munging all errors into EIO.

  Internally, the bulk of the changes are Christoph's patchset to reduce
  the indirect function call count by a third to a half by converting
  iomap iteration from a loop pattern to a generator/consumer pattern.
  As an added bonus, fsdax no longer open-codes iomap apply loops.

  Summary:

   - Simplify the bio_end_page usage in the buffered IO code.

   - Support reading inline data at nonzero offsets for erofs.

   - Fix some typos and bad grammar.

   - Convert kmap_atomic usage in the inline data read path.

   - Add some extra inline data input checking.

   - Fix a memory corruption bug stemming from iomap_swapfile_activate
     trying to activate more pages than mm was expecting.

   - Pass errnos through the page writeback code so that writeback
     errors are reported correctly instead of being munged to EIO.

   - Replace iomap_apply with a open-coded iterator loops to reduce the
     number of indirect calls by a third to a half.

   - Refactor the fsdax code to use iomap iterators instead of the
     open-coded iomap_apply code that it had before.

   - Format file range iomap tracepoint data in hexadecimal and
     standardize the names used in the pretty-print string"

* tag 'iomap-5.15-merge-4' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: (41 commits)
  iomap: standardize tracepoint formatting and storage
  mm/swap: consider max pages in iomap_swapfile_add_extent
  iomap: move loop control code to iter.c
  iomap: constify iomap_iter_srcmap
  fsdax: switch the fault handlers to use iomap_iter
  fsdax: factor out a dax_fault_actor() helper
  fsdax: factor out helpers to simplify the dax fault code
  iomap: rework unshare flag
  iomap: pass an iomap_iter to various buffered I/O helpers
  iomap: remove iomap_apply
  fsdax: switch dax_iomap_rw to use iomap_iter
  iomap: switch iomap_swapfile_activate to use iomap_iter
  iomap: switch iomap_seek_data to use iomap_iter
  iomap: switch iomap_seek_hole to use iomap_iter
  iomap: switch iomap_bmap to use iomap_iter
  iomap: switch iomap_fiemap to use iomap_iter
  iomap: switch __iomap_dio_rw to use iomap_iter
  iomap: switch iomap_page_mkwrite to use iomap_iter
  iomap: switch iomap_zero_range to use iomap_iter
  iomap: switch iomap_file_unshare to use iomap_iter
  ...
2021-08-31 11:13:35 -07:00
Linus Torvalds
87045e6546 for-5.15-tag
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEE8rQSAMVO+zA4DBdWxWXV+ddtWDsFAmEs2NIACgkQxWXV+ddt
 WDsJMQ/+PJ/yXfI85mAeAzTJLWQ0zD6YO3iBhf3wOeyychWC4on435pj+zW8zR/U
 /bix25ygoWF4MvGF6p0uyv4Z5mnvkZXE5lapUcJu6wXG7se1QRPH0broTh05IBXK
 SnT93Eb9RexaiNFk7DVma9XkviqZ/ZISPtkJ9wYrfIba7j/U/wa+PtEFS7wk58hP
 rFQXgV64xm/pcP28YYHfOkCjdyUMdJrnBUvfKOlX6d94lmYbP5lyiTL+XJEXExzN
 wPakD0UsnXPr4TRvf+YRTPeFHPPUgyORII7otVUOKmGywWtcJrELX8rXFoW+6GwB
 dzZIcSYXHUxU5UrtMbZgiztVBJ+bQY5juYMIrj13eYOMYkijxAqPP84iDO15+TSV
 zNqyAVjUglHCGUGjhSpAxnAmtp+IJTZfVAWcvIKq3VqvJtb8tssQsk9bqFjH1xlH
 qNJLE57CYe3tjw05K9y0keMh2iJWRWkXZYkgI/zjwo5nreemobpN+3fO4yneVLh7
 ecdBmSl/JVSzAB1NamLOCZNGZLUqiiuTvZlJtI6ZsekrN1+4A6QzVcU/MGjSYL1v
 C7W0hK0LF+e3xIBkxTKVq8noolsgbmlWacxJq8fZq9HwZy5IVJOVm9STDlCuLaIo
 gPr0V0itkclcsMU0CHTyCjMsfuHYUwJZXwg93wKfJf5UCzS4OWU=
 =ALO9
 -----END PGP SIGNATURE-----

Merge tag 'for-5.15-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs updates from David Sterba:
 "The highlights of this round are integrations with fs-verity and
  idmapped mounts, the rest is usual mix of minor improvements, speedups
  and cleanups.

  There are some patches outside of btrfs, namely updating some VFS
  interfaces, all straightforward and acked.

  Features:

   - fs-verity support, using standard ioctls, backward compatible with
     read-only limitation on inodes with previously enabled fs-verity

   - idmapped mount support

   - make mount with rescue=ibadroots more tolerant to partially damaged
     trees

   - allow raid0 on a single device and raid10 on two devices,
     degenerate cases but might be useful as an intermediate step during
     conversion to other profiles

   - zoned mode block group auto reclaim can be disabled via sysfs knob

  Performance improvements:

   - continue readahead of node siblings even if target node is in
     memory, could speed up full send (on sample test +11%)

   - batching of delayed items can speed up creating many files

   - fsync/tree-log speedups
       - avoid unnecessary work (gains +2% throughput, -2% run time on
         sample load)
       - reduced lock contention on renames (on dbench +4% throughput,
         up to -30% latency)

  Fixes:

   - various zoned mode fixes

   - preemptive flushing threshold tuning, avoid excessive work on
     almost full filesystems

  Core:

   - continued subpage support, preparation for implementing remaining
     features like compression and defragmentation; with some
     limitations, write is now enabled on 64K page systems with 4K
     sectors, still considered experimental
       - no readahead on compressed reads
       - inline extents disabled
       - disabled raid56 profile conversion and mount

   - improved flushing logic, fixing early ENOSPC on some workloads

   - inode flags have been internally split to read-only and read-write
     incompat bit parts, used by fs-verity

   - new tree items for fs-verity
       - descriptor item
       - Merkle tree item

   - inode operations extended to be namespace-aware

   - cleanups and refactoring

  Generic code changes:

   - fs: new export filemap_fdatawrite_wbc

   - fs: removed sync_inode

   - block: bio_trim argument type fixups

   - vfs: add namespace-aware lookup"

* tag 'for-5.15-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: (114 commits)
  btrfs: reset replace target device to allocation state on close
  btrfs: zoned: fix ordered extent boundary calculation
  btrfs: do not do preemptive flushing if the majority is global rsv
  btrfs: reduce the preemptive flushing threshold to 90%
  btrfs: tree-log: check btrfs_lookup_data_extent return value
  btrfs: avoid unnecessarily logging directories that had no changes
  btrfs: allow idmapped mount
  btrfs: handle ACLs on idmapped mounts
  btrfs: allow idmapped INO_LOOKUP_USER ioctl
  btrfs: allow idmapped SUBVOL_SETFLAGS ioctl
  btrfs: allow idmapped SET_RECEIVED_SUBVOL ioctls
  btrfs: relax restrictions for SNAP_DESTROY_V2 with subvolids
  btrfs: allow idmapped SNAP_DESTROY ioctls
  btrfs: allow idmapped SNAP_CREATE/SUBVOL_CREATE ioctls
  btrfs: check whether fsgid/fsuid are mapped during subvolume creation
  btrfs: allow idmapped permission inode op
  btrfs: allow idmapped setattr inode op
  btrfs: allow idmapped tmpfile inode op
  btrfs: allow idmapped symlink inode op
  btrfs: allow idmapped mkdir inode op
  ...
2021-08-31 09:41:22 -07:00
Qu Wenruo
4e9655763b Revert "btrfs: compression: don't try to compress if we don't have enough pages"
This reverts commit f216562731.

[BUG]
It's no longer possible to create compressed inline extent after commit
f216562731 ("btrfs: compression: don't try to compress if we don't
have enough pages").

[CAUSE]
For compression code, there are several possible reasons we have a range
that needs to be compressed while it's no more than one page.

- Compressed inline write
  The data is always smaller than one sector and the test lacks the
  condition to properly recognize a non-inline extent.

- Compressed subpage write
  For the incoming subpage compressed write support, we require page
  alignment of the delalloc range.
  And for 64K page size, we can compress just one page into smaller
  sectors.

For those reasons, the requirement for the data to be more than one page
is not correct, and is already causing regression for compressed inline
data writeback.  The idea of skipping one page to avoid wasting CPU time
could be revisited in the future.

[FIX]
Fix it by reverting the offending commit.

Reported-by: Zygo Blaxell <ce3g8jdj@umail.furryterror.org>
Link: https://lore.kernel.org/linux-btrfs/afa2742.c084f5d6.17b6b08dffc@tnonline.net
Fixes: f216562731 ("btrfs: compression: don't try to compress if we don't have enough pages")
CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-25 15:08:19 +02:00
Christian Brauner
4d4340c912 btrfs: allow idmapped SNAP_CREATE/SUBVOL_CREATE ioctls
Creating subvolumes and snapshots is one of the core features of btrfs
and is even available to unprivileged users. Make it possible to use
subvolume and snapshot creation on idmapped mounts. This is a fairly
straightforward operation since all the permission checking helpers are
already capable of handling idmapped mounts. So we just need to pass
down the mount's userns.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23 13:19:14 +02:00
Christian Brauner
3bc71ba02c btrfs: allow idmapped permission inode op
Enable btrfs_permission() to handle idmapped mounts. This is just a
matter of passing down the mount's userns.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23 13:19:13 +02:00
Christian Brauner
d4d0946461 btrfs: allow idmapped setattr inode op
Enable btrfs_setattr() to handle idmapped mounts. This is just a matter
of passing down the mount's userns.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23 13:19:13 +02:00
Christian Brauner
98b6ab5fc0 btrfs: allow idmapped tmpfile inode op
Enable btrfs_tmpfile() to handle idmapped mounts. This is just a matter
of passing down the mount's userns.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23 13:19:13 +02:00
Christian Brauner
5a0521086e btrfs: allow idmapped symlink inode op
Enable btrfs_symlink() to handle idmapped mounts. This is just a matter
of passing down the mount's userns.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23 13:19:13 +02:00
Christian Brauner
b0b3e44d34 btrfs: allow idmapped mkdir inode op
Enable btrfs_mkdir() to handle idmapped mounts. This is just a matter of
passing down the mount's userns.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23 13:19:13 +02:00
Christian Brauner
e93ca491d0 btrfs: allow idmapped create inode op
Enable btrfs_create() to handle idmapped mounts. This is just a matter
of passing down the mount's userns.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23 13:19:13 +02:00
Christian Brauner
72105277dc btrfs: allow idmapped mknod inode op
Enable btrfs_mknod() to handle idmapped mounts. This is just a matter of
passing down the mount's userns.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23 13:19:12 +02:00
Christian Brauner
c020d2eaf1 btrfs: allow idmapped getattr inode op
Enable btrfs_getattr() to handle idmapped mounts. This is just a matter
of passing down the mount's userns.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23 13:19:12 +02:00
Christian Brauner
ca07274c3d btrfs: allow idmapped rename inode op
Enable btrfs_rename() to handle idmapped mounts. This is just a matter
of passing down the mount's userns.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23 13:19:12 +02:00
Christian Brauner
b3b6f5b922 btrfs: handle idmaps in btrfs_new_inode()
Extend btrfs_new_inode() to take the idmapped mount into account when
initializing a new inode. This is just a matter of passing down the
mount's userns. The rest is taken care of in inode_init_owner(). This is
a preliminary patch to make the individual btrfs inode operations
idmapped mount aware.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23 13:19:12 +02:00
Naohiro Aota
63fb5879db btrfs: zoned: add asserts on splitting extent_map
We call split_zoned_em() on an extent_map on submitting a bio for it. Thus,
we can assume the extent_map is PINNED, not LOGGING, and in the modified
list. Add ASSERT()s to ensure the extent_maps after the split also has the
proper flags set and are in the modified list.

Suggested-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23 13:19:11 +02:00
Filipe Manana
1c167b87f4 btrfs: remove unnecessary NULL check for the new inode during rename exchange
At the very end of btrfs_rename_exchange(), in case an error happened, we
are checking if 'new_inode' is NULL, but that is not needed since during a
rename exchange, unlike regular renames, 'new_inode' can never be NULL,
and if it were, we would have a crashed much earlier when we dereference it
multiple times.

So remove the check because it is not necessary and because it is causing
static checkers to emit a warning. I probably introduced the check by
copy-pasting similar code from btrfs_rename(), where 'new_inode' can be
NULL, in commit 86e8aa0e77 ("Btrfs: unpin logs if rename exchange
operation fails").

Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23 13:19:10 +02:00
Boris Burkov
705242538f btrfs: verity metadata orphan items
Writing out the verity data is too large of an operation to do in a
single transaction. If we are interrupted before we finish creating
fsverity metadata for a file, or fail to clean up already created
metadata after a failure, we could leak the verity items that we already
committed.

To address this issue, we use the orphan mechanism. When we start
enabling verity on a file, we also add an orphan item for that inode.
When we are finished, we delete the orphan. However, if we are
interrupted midway, the orphan will be present at mount and we can
cleanup the half-formed verity state.

There is a possible race with a normal unlink operation: if unlink and
verity run on the same file in parallel, it is possible for verity to
succeed and delete the still legitimate orphan added by unlink. Then, if
we are interrupted and mount in that state, we will never clean up the
inode properly. This is also possible for a file created with O_TMPFILE.
Check nlink==0 before deleting to avoid this race.

A final thing to note is that this is a resurrection of using orphans to
signal an operation besides "delete this inode". The old case was to
signal the need to do a truncate. That case still technically applies
for mounting very old file systems, so we need to take some care to not
clobber it. To that end, we just have to be careful that verity orphan
cleanup is a no-op for non-verity files.

Signed-off-by: Boris Burkov <boris@bur.io>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23 13:19:09 +02:00
Boris Burkov
146054090b btrfs: initial fsverity support
Add support for fsverity in btrfs. To support the generic interface in
fs/verity, we add two new item types in the fs tree for inodes with
verity enabled. One stores the per-file verity descriptor and btrfs
verity item and the other stores the Merkle tree data itself.

Verity checking is done in end_page_read just before a page is marked
uptodate. This naturally handles a variety of edge cases like holes,
preallocated extents, and inline extents. Some care needs to be taken to
not try to verity pages past the end of the file, which are accessed by
the generic buffered file reading code under some circumstances like
reading to the end of the last page and trying to read again. Direct IO
on a verity file falls back to buffered reads.

Verity relies on PageChecked for the Merkle tree data itself to avoid
re-walking up shared paths in the tree. For this reason, we need to
cache the Merkle tree data. Since the file is immutable after verity is
turned on, we can cache it at an index past EOF.

Use the new inode ro_flags to store verity on the inode item, so that we
can enable verity on a file, then rollback to an older kernel and still
mount the file system and read the file. Since we can't safely write the
file anymore without ruining the invariants of the Merkle tree, we mark
a ro_compat flag on the file system when a file has verity enabled.

Acked-by: Eric Biggers <ebiggers@google.com>
Co-developed-by: Chris Mason <clm@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
Signed-off-by: Boris Burkov <boris@bur.io>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23 13:19:09 +02:00
Boris Burkov
77eea05e78 btrfs: add ro compat flags to inodes
Currently, inode flags are fully backwards incompatible in btrfs. If we
introduce a new inode flag, then tree-checker will detect it and fail.
This can even cause us to fail to mount entirely. To make it possible to
introduce new flags which can be read-only compatible, like VERITY, we
add new ro flags to btrfs without treating them quite so harshly in
tree-checker. A read-only file system can survive an unexpected flag,
and can be mounted.

As for the implementation, it unfortunately gets a little complicated.

The on-disk representation of the inode, btrfs_inode_item, has an __le64
for flags but the in-memory representation, btrfs_inode, uses a u32.
David Sterba had the nice idea that we could reclaim those wasted 32 bits
on disk and use them for the new ro_compat flags.

It turns out that the tree-checker code which checks for unknown flags
is broken, and ignores the upper 32 bits we are hoping to use. The issue
is that the flags use the literal 1 rather than 1ULL, so the flags are
signed ints, and one of them is specifically (1 << 31). As a result, the
mask which ORs the flags is a negative integer on machines where int is
32 bit twos complement. When tree-checker evaluates the expression:

  btrfs_inode_flags(leaf, iitem) & ~BTRFS_INODE_FLAG_MASK)

The mask is something like 0x80000abc, which gets promoted to u64 with
sign extension to 0xffffffff80000abc. Negating that 64 bit mask leaves
all the upper bits zeroed, and we can't detect unexpected flags.

This suggests that we can't use those bits after all. Luckily, we have
good reason to believe that they are zero anyway. Inode flags are
metadata, which is always checksummed, so any bit flips that would
introduce 1s would cause a checksum failure anyway (excluding the
improbable case of the checksum getting corrupted exactly badly).

Further, unless the 1 << 31 flag is used, the cast to u64 of the 32 bit
inode flag should preserve its value and not add leading zeroes
(at least for twos complement). The only place that flag
(BTRFS_INODE_ROOT_ITEM_INIT) is used is in a special inode embedded in
the root item, and indeed for that inode we see 0xffffffff80000000 as
the flags on disk. However, that inode is never seen by tree checker,
nor is it used in a context where verity might be meaningful.
Theoretically, a future ro flag might cause trouble on that inode, so we
should proactively clean up that mess before it does.

With the introduction of the new ro flags, keep two separate unsigned
masks and check them against the appropriate u32. Since we no longer run
afoul of sign extension, this also stops writing out 0xffffffff80000000
in root_item inodes going forward.

Signed-off-by: Boris Burkov <boris@bur.io>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23 13:19:09 +02:00
Qu Wenruo
7361b4ae03 btrfs: remove the dead comment in writepage_delalloc()
When btrfs_run_delalloc_range() failed, we will error out.

But there is a strange comment mentioning that
btrfs_run_delalloc_range() could have returned value >0 to indicate the
IO has already started.

Commit 40f765805f ("Btrfs: split up __extent_writepage to lower stack
usage") introduced the comment, but unfortunately at that time, we were
already using @page_started to indicate that case, and still return 0.

Furthermore, even if that comment was right (which is not), we would
return -EIO if the IO had already started.

By all means the comment is incorrect, just remove the comment along
with the dead check.

Just to be extra safe, add an ASSERT() in btrfs_run_delalloc_range() to
make sure we either return 0 or error, no positive return value.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23 13:19:08 +02:00
Filipe Manana
bd54f381a1 btrfs: do not pin logs too early during renames
During renames we pin the logs of the roots a bit too early, before the
calls to btrfs_insert_inode_ref(). We can pin the logs after those calls,
since those will not change anything in a log tree.

In a scenario where we have multiple and diverse filesystem operations
running in parallel, those calls can take a significant amount of time,
due to lock contention on extent buffers, and delay log commits from other
tasks for longer than necessary.

So just pin logs after calls to btrfs_insert_inode_ref() and right before
the first operation that can update a log tree.

The following script that uses dbench was used for testing:

  $ cat dbench-test.sh
  #!/bin/bash

  DEV=/dev/nvme0n1
  MNT=/mnt/nvme0n1
  MOUNT_OPTIONS="-o ssd"
  MKFS_OPTIONS="-m single -d single"

  echo "performance" | tee /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor

  umount $DEV &> /dev/null
  mkfs.btrfs -f $MKFS_OPTIONS $DEV
  mount $MOUNT_OPTIONS $DEV $MNT

  dbench -D $MNT -t 120 16

  umount $MNT

The tests were run on a machine with 12 cores, 64G of RAN, a NVMe device
and using a non-debug kernel config (Debian's default config).

The results compare a branch without this patch and without the previous
patch in the series, that has the subject:

 "btrfs: eliminate some false positives when checking if inode was logged"

Versus the same branch with these two patches applied.

dbench with 8 clients, results before:

 Operation      Count    AvgLat    MaxLat
 ----------------------------------------
 NTCreateX    4391359     0.009   249.745
 Close        3225882     0.001     3.243
 Rename        185953     0.065   240.643
 Unlink        886669     0.049   249.906
 Deltree          112     2.455   217.433
 Mkdir             56     0.002     0.004
 Qpathinfo    3980281     0.004     3.109
 Qfileinfo     697579     0.001     0.187
 Qfsinfo       729780     0.002     2.424
 Sfileinfo     357764     0.004     1.415
 Find         1538861     0.016     4.863
 WriteX       2189666     0.010     3.327
 ReadX        6883443     0.002     0.729
 LockX          14298     0.002     0.073
 UnlockX        14298     0.001     0.042
 Flush         307777     2.447   303.663

Throughput 1149.6 MB/sec  8 clients  8 procs  max_latency=303.666 ms

dbench with 8 clients, results after:

 Operation      Count    AvgLat    MaxLat
 ----------------------------------------
 NTCreateX    4269920     0.009   213.532
 Close        3136653     0.001     0.690
 Rename        180805     0.082   213.858
 Unlink        862189     0.050   172.893
 Deltree          112     2.998   218.328
 Mkdir             56     0.002     0.003
 Qpathinfo    3870158     0.004     5.072
 Qfileinfo     678375     0.001     0.194
 Qfsinfo       709604     0.002     0.485
 Sfileinfo     347850     0.004     1.304
 Find         1496310     0.017     5.504
 WriteX       2129613     0.010     2.882
 ReadX        6693066     0.002     1.517
 LockX          13902     0.002     0.075
 UnlockX        13902     0.001     0.055
 Flush         299276     2.511   220.189

Throughput 1187.33 MB/sec  8 clients  8 procs  max_latency=220.194 ms

+3.2% throughput, -31.8% max latency

dbench with 16 clients, results before:

 Operation      Count    AvgLat    MaxLat
 ----------------------------------------
 NTCreateX    5978334     0.028   156.507
 Close        4391598     0.001     1.345
 Rename        253136     0.241   155.057
 Unlink       1207220     0.182   257.344
 Deltree          160     6.123    36.277
 Mkdir             80     0.003     0.005
 Qpathinfo    5418817     0.012     6.867
 Qfileinfo     949929     0.001     0.941
 Qfsinfo       993560     0.002     1.386
 Sfileinfo     486904     0.004     2.829
 Find         2095088     0.059     8.164
 WriteX       2982319     0.017     9.029
 ReadX        9371484     0.002     4.052
 LockX          19470     0.002     0.461
 UnlockX        19470     0.001     0.990
 Flush         418936     2.740   347.902

Throughput 1495.31 MB/sec  16 clients  16 procs  max_latency=347.909 ms

dbench with 16 clients, results after:

 Operation      Count    AvgLat    MaxLat
 ----------------------------------------
 NTCreateX    5711833     0.029   131.240
 Close        4195897     0.001     1.732
 Rename        241849     0.204   147.831
 Unlink       1153341     0.184   231.322
 Deltree          160     6.086    30.198
 Mkdir             80     0.003     0.021
 Qpathinfo    5177011     0.012     7.150
 Qfileinfo     907768     0.001     0.793
 Qfsinfo       949205     0.002     1.431
 Sfileinfo     465317     0.004     2.454
 Find         2001541     0.058     7.819
 WriteX       2850661     0.017     9.110
 ReadX        8952289     0.002     3.991
 LockX          18596     0.002     0.655
 UnlockX        18596     0.001     0.179
 Flush         400342     2.879   293.607

Throughput 1565.73 MB/sec  16 clients  16 procs  max_latency=293.611 ms

+4.6% throughput, -16.9% max latency

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23 13:19:08 +02:00
Naohiro Aota
42b5d73b5d btrfs: drop unnecessary ASSERT from btrfs_submit_direct()
When on SINGLE block group, btrfs_get_io_geometry() will return "the
size of the block group - the offset of the logical address within the
block group" as geom.len. Since we allow up to 8 GiB zone size on zoned
filesystem, we can have up to 8 GiB block group, so can have up to 8 GiB
geom.len as well. With this setup, we easily hit the "ASSERT(geom.len <=
INT_MAX);".

The ASSERT looks like to guard btrfs_bio_clone_partial() and bio_trim()
which both take "int" (now u64 due to the previous patch). So to be
precise the ASSERT should check if clone_len <= UINT_MAX. But actually,
clone_len is already capped by bio.bi_iter.bi_size which is unsigned
int. So the ASSERT is not necessary.

Drop the ASSERT and properly compare submit_len and geom.len in u64.
Then, let the implicit casting to convert it to u64.

Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23 13:19:08 +02:00
Josef Bacik
b377630527 btrfs: use the filemap_fdatawrite_wbc helper for delalloc shrinking
sync_inode() has some holes that can cause problems if we're under heavy
ENOSPC pressure.  If there's writeback running on a separate thread
sync_inode() will skip writing the inode altogether.  What we really
want is to make sure writeback has been started on all the pages to make
sure we can see the ordered extents and wait on them if appropriate.
Switch to this new helper which will allow us to accomplish this and
avoid ENOSPC'ing early.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23 13:19:07 +02:00
Josef Bacik
e16460707e btrfs: wait on async extents when flushing delalloc
I've been debugging an early ENOSPC problem in production and finally
root caused it to this problem.  When we switched to the per-inode in
38d715f494 ("btrfs: use btrfs_start_delalloc_roots in
shrink_delalloc") I pulled out the async extent handling, because we
were doing the correct thing by calling filemap_flush() if we had async
extents set.  This would properly wait on any async extents by locking
the page in the second flush, thus making sure our ordered extents were
properly set up.

However when I switched us back to page based flushing, I used
sync_inode(), which allows us to pass in our own wbc.  The problem here
is that sync_inode() is smarter than the filemap_* helpers, it tries to
avoid calling writepages at all.  This means that our second call could
skip calling do_writepages altogether, and thus not wait on the pagelock
for the async helpers.  This means we could come back before any ordered
extents were created and then simply continue on in our flushing
mechanisms and ENOSPC out when we have plenty of space to use.

Fix this by putting back the async pages logic in shrink_delalloc.  This
allows us to bulk write out everything that we need to, and then we can
wait in one place for the async helpers to catch up, and then wait on
any ordered extents that are created.

Fixes: e076ab2a2c ("btrfs: shrink delalloc pages instead of full inodes")
CC: stable@vger.kernel.org # 5.10+
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23 13:19:07 +02:00
Josef Bacik
ac98141d14 btrfs: wake up async_delalloc_pages waiters after submit
We use the async_delalloc_pages mechanism to make sure that we've
completed our async work before trying to continue our delalloc
flushing.  The reason for this is we need to see any ordered extents
that were created by our delalloc flushing.  However we're waking up
before we do the submit work, which is before we create the ordered
extents.  This is a pretty wide race window where we could potentially
think there are no ordered extents and thus exit shrink_delalloc
prematurely.  Fix this by waking us up after we've done the work to
create ordered extents.

CC: stable@vger.kernel.org # 5.4+
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23 13:19:06 +02:00
Qu Wenruo
95ea0486b2 btrfs: allow read-write for 4K sectorsize on 64K page size systems
Since now we support data and metadata read-write for subpage, remove
the RO requirement for subpage mount.

There are some extra limitations though:

- For now, subpage RW mount is still considered experimental
  Thus that mount warning will still be there.

- No compression support
  There are still quite some PAGE_SIZE hard coded and quite some call
  sites use extent_clear_unlock_delalloc() to unlock locked_page.
  This will screw up subpage helpers.

  Now for subpage RW mount, no matter what mount option or inode attr is
  set, all writes will not be compressed.  Although reading compressed
  data has no problem.

- No defrag for subpage case
  The defrag support for subpage case will come in later patches, which
  will also rework the defrag workflow.

- No inline extent will be created
  This is mostly due to the fact that filemap_fdatawrite_range() will
  trigger more write than the range specified.
  In fallocate calls, this behavior can make us to writeback which can
  be inlined, before we enlarge the i_size.

  This is a very special corner case, and even current btrfs check won't
  report error on such inline extent + regular extent.
  But considering how much effort has been put to prevent such inline +
  regular, I'd prefer to cut off inline extent completely until we have
  a good solution.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23 13:19:06 +02:00
Qu Wenruo
e3c62324e4 btrfs: subpage: fix false alert when relocating partial preallocated data extents
[BUG]
When relocating partial preallocated data extents (part of the
preallocated extent is written) for subpage, it can cause the following
false alert and make the relocation to fail:

  BTRFS info (device dm-3): balance: start -d
  BTRFS info (device dm-3): relocating block group 13631488 flags data
  BTRFS warning (device dm-3): csum failed root -9 ino 257 off 4096 csum 0x98757625 expected csum 0x00000000 mirror 1
  BTRFS error (device dm-3): bdev /dev/mapper/arm_nvme-test errs: wr 0, rd 0, flush 0, corrupt 1, gen 0
  BTRFS warning (device dm-3): csum failed root -9 ino 257 off 4096 csum 0x98757625 expected csum 0x00000000 mirror 1
  BTRFS error (device dm-3): bdev /dev/mapper/arm_nvme-test errs: wr 0, rd 0, flush 0, corrupt 2, gen 0
  BTRFS info (device dm-3): balance: ended with status: -5

The minimal script to reproduce looks like this:

  mkfs.btrfs -f -s 4k $dev
  mount $dev -o nospace_cache $mnt
  xfs_io -f -c "falloc 0 8k" $mnt/file
  xfs_io -f -c "pwrite 0 4k" $mnt/file
  btrfs balance start -d $mnt

[CAUSE]
Function btrfs_verify_data_csum() checks if the full range has
EXTENT_NODATASUM bit for data reloc inode, if *all* bytes of the range
have EXTENT_NODATASUM bit, then it skip the range.

This works pretty well for regular sectorsize, as in that case
btrfs_verify_data_csum() is called for each sector, thus no problem at
all.

But for subpage case, btrfs_verify_data_csum() is called on each bvec,
which can contain several sectors, and since it checks *all* bytes for
EXTENT_NODATASUM bit, if we have some range with csum, then we will
continue checking all the sectors.

For the preallocated sectors, it doesn't have any csum, thus obviously
the csum won't match and cause the false alert.

[FIX]
Move the EXTENT_NODATASUM check into the main loop, so that we can check
each sector for EXTENT_NODATASUM bit for subpage case.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23 13:19:05 +02:00
Qu Wenruo
7c11d0ae43 btrfs: subpage: fix a potential use-after-free in writeback helper
[BUG]
There is a possible use-after-free bug when running generic/095.

 BUG: Unable to handle kernel data access on write at 0x6b6b6b6b6b6b725b
 Faulting instruction address: 0xc000000000283654
 c000000000283078 do_raw_spin_unlock+0x88/0x230
 c0000000012b1e14 _raw_spin_unlock_irqrestore+0x44/0x90
 c000000000a918dc btrfs_subpage_clear_writeback+0xac/0xe0
 c0000000009e0458 end_bio_extent_writepage+0x158/0x270
 c000000000b6fd14 bio_endio+0x254/0x270
 c0000000009fc0f0 btrfs_end_bio+0x1a0/0x200
 c000000000b6fd14 bio_endio+0x254/0x270
 c000000000b781fc blk_update_request+0x46c/0x670
 c000000000b8b394 blk_mq_end_request+0x34/0x1d0
 c000000000d82d1c lo_complete_rq+0x11c/0x140
 c000000000b880a4 blk_complete_reqs+0x84/0xb0
 c0000000012b2ca4 __do_softirq+0x334/0x680
 c0000000001dd878 irq_exit+0x148/0x1d0
 c000000000016f4c do_IRQ+0x20c/0x240
 c000000000009240 hardware_interrupt_common_virt+0x1b0/0x1c0

[CAUSE]
There is very small race window like the following in generic/095.

	Thread 1		|		Thread 2
--------------------------------+------------------------------------
  end_bio_extent_writepage()	| btrfs_releasepage()
  |- spin_lock_irqsave()	| |
  |- end_page_writeback()	| |
  |				| |- if (PageWriteback() ||...)
  |				| |- clear_page_extent_mapped()
  |				|    |- kfree(subpage);
  |- spin_unlock_irqrestore().

The race can also happen between writeback and btrfs_invalidatepage(),
although that would be much harder as btrfs_invalidatepage() has much
more work to do before the clear_page_extent_mapped() call.

[FIX]
Here we "wait" for the subapge spinlock to be released before we detach
subpage structure.
So this patch will introduce a new function, wait_subpage_spinlock(), to
do the "wait" by acquiring the spinlock and release it.

Since the caller has ensured the page is not dirty nor writeback, and
page is already locked, the only way to hold the subpage spinlock is
from endio function.
Thus we only need to acquire the spinlock to wait for any existing
holder.

Reported-by: Ritesh Harjani <riteshh@linux.ibm.com>
Tested-by: Ritesh Harjani <riteshh@linux.ibm.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23 13:19:05 +02:00
Qu Wenruo
7367253a35 btrfs: subpage: disable inline extent creation
[BUG]
When running the following fsx command (extracted from generic/127) on
subpage filesystem, it can create inline extent with regular extents:

  fsx -q -l 262144 -o 65536 -S 191110531 -N 9057 -R -W $mnt/file > /tmp/fsx

The offending extent would look like:

  item 9 key (257 INODE_REF 256) itemoff 15703 itemsize 14
    index 2 namelen 4 name: file
  item 10 key (257 EXTENT_DATA 0) itemoff 14975 itemsize 728
    generation 7 type 0 (inline)
    inline extent data size 707 ram_bytes 707 compression 0 (none)
  item 11 key (257 EXTENT_DATA 4096) itemoff 14922 itemsize 53
    generation 7 type 2 (prealloc)
    prealloc data disk byte 102346752 nr 4096
    prealloc data offset 0 nr 4096

[CAUSE]
For subpage filesystem, the writeback is triggered in page units, which
means, even if we just want to writeback range [16K, 20K) for 64K page
system, we will still try to writeback any dirty sector of range [0, 64K).

This is never a problem if sectorsize == PAGE_SIZE, but for subpage,
this can cause unexpected problems.

For above test case, the last several operations from fsx are:

 9055 trunc      from 0x40000 to 0x2c3
 9057 falloc     from 0x164c to 0x19d2 (0x386 bytes)

In operation 9055, we dirtied sector [0, 4096), then in falloc, we call
btrfs_wait_ordered_range(inode, start=4096, len=4096), only expecting to
writeback any dirty data in [4096, 8192), but nothing else.

Unfortunately, in subpage case, above btrfs_wait_ordered_range() will
trigger writeback of the range [0, 64K), which includes the data at
[0, 4096).

And since at the call site, we haven't yet increased i_size, which is
still 707, this means cow_file_range() can insert an inline extent.

Resulting above inline + regular extent.

[WORKAROUND]
I don't really have any good short-term solution yet, as this means all
operations that would trigger writeback need to be reviewed for any
i_size change.

So here I choose to disable inline extent creation for subpage case as a
workaround.  We have done tons of work just to avoid such extent, so I
don't to create an exception just for subpage.

This only affects inline extent creation, subpage has no problem reading
existing inline extents at all.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23 13:19:05 +02:00
Qu Wenruo
3670e6451b btrfs: subpage: check if there are compressed extents inside one page
[BUG]
When testing experimental subpage compressed write support, it hits a
NULL pointer dereference inside read path:

 Unable to handle kernel NULL pointer dereference at virtual address 0000000000000018
 pc : __pi_memcmp+0x28/0x1ec
 lr : check_data_csum+0xd0/0x274 [btrfs]
 Call trace:
  __pi_memcmp+0x28/0x1ec
  btrfs_verify_data_csum+0xf4/0x244 [btrfs]
  end_bio_extent_readpage+0x1d0/0x6b0 [btrfs]
  bio_endio+0x15c/0x1dc
  end_workqueue_fn+0x44/0x64 [btrfs]
  btrfs_work_helper+0x74/0x250 [btrfs]
  process_one_work+0x1d4/0x47c
  worker_thread+0x180/0x400
  kthread+0x11c/0x120
  ret_from_fork+0x10/0x30
 Code: 54000261 d100044c d343fd8c f8408403 (f8408424)
 ---[ end trace 9e2c59f33ea40866 ]---

[CAUSE]
When reading two compressed extents inside the same page, like the
following layout, we trigger above crash:

	0	32K	64K
	|-------|\\\\\\\|
	     |	     \- Compressed extent (A)
	     \--------- Compressed extent (B)

For compressed read, we don't need to populate its io_bio->csum, as we
rely on compressed_bio->csum to verify the compressed data, and then
copy the decompressed to inode pages.

Normally btrfs_verify_data_csum() skip such page by checking and
clearing its PageChecked flag

But since that flag is still for the full page, when endio for inode
page range [0, 32K) gets executed, it clears PageChecked flag for the
full page.

Then when endio for inode page range [32K, 64K) gets executed, since the
page no longer has PageChecked flag, it just continues checking, even
though io_bio->csum is NULL.

[FIX]
Thankfully there are only two users of PageChecked bit:

- Cow fixup
  Since subpage has its own way to trace page dirty (dirty_bitmap) and
  ordered bit (ordered_bitmap), it should never trigger cow fixup.

- Compressed read
  We can distinguish such read by just checking io_bio->csum.

So just check io_bio->csum before doing the verification to avoid such
NULL pointer dereference.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23 13:19:03 +02:00
David Sterba
f41b6ba93d btrfs: remove uptodate parameter from btrfs_dec_test_first_ordered_pending
In commit e65f152e43 ("btrfs: refactor how we finish ordered extent io
for endio functions") there was last caller not using 1 for the uptodate
parameter. Now there's only one, passing 1, so we can remove it and
simplify the code.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23 13:19:02 +02:00
David Sterba
25c1252a02 btrfs: switch uptodate to bool in btrfs_writepage_endio_finish_ordered
The uptodate parameter should be bool, change the type.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23 13:19:02 +02:00
Qu Wenruo
a129ffb816 btrfs: remove unused start and end parameters from btrfs_run_delalloc_range()
Since commit d75855b451 ("btrfs: Remove
extent_io_ops::writepage_start_hook") removes the writepage_start_hook()
and adds btrfs_writepage_cow_fixup() function, there is no need to
follow the old hook parameters.

Remove the @start and @end hook, since currently the fixup check is full
page check, it doesn't need @start and @end hook.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23 13:19:02 +02:00
Filipe Manana
cceaa89f02 btrfs: remove racy and unnecessary inode transaction update when using no-holes
When using the NO_HOLES feature and expanding the size of an inode, we
update the inode's last_trans, last_sub_trans and last_log_commit fields
at maybe_insert_hole() so that a fsync does know that the inode needs to
be logged (by making sure that btrfs_inode_in_log() returns false). This
happens for expanding truncate operations, buffered writes, direct IO
writes and when cloning extents to an offset greater than the inode's
i_size.

However the way we do it is racy, because in between setting the inode's
last_sub_trans and last_log_commit fields, the log transaction ID that was
assigned to last_sub_trans might be committed before we read the root's
last_log_commit and assign that value to last_log_commit. If that happens
it would make a future call to btrfs_inode_in_log() return true. This is
a race that should be extremely unlikely to be hit in practice, and it is
the same that was described by commit bc0939fcfa ("btrfs: fix race
between marking inode needs to be logged and log syncing").

The fix would simply be to set last_log_commit to the value we assigned
to last_sub_trans minus 1, like it was done in that commit. However
updating these two fields plus the last_trans field is pointless here
because all the callers of btrfs_cont_expand() (which is the only
caller of maybe_insert_hole()) always call btrfs_set_inode_last_trans()
or btrfs_update_inode() after calling btrfs_cont_expand(). Calling either
btrfs_set_inode_last_trans() or btrfs_update_inode() guarantees that the
next fsync will log the inode, as it makes btrfs_inode_in_log() return
false.

So just remove the code that explicitly sets the inode's last_trans,
last_sub_trans and last_log_commit fields.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23 13:19:01 +02:00
David Sterba
4c2bf276b5 btrfs: compression: drop kmap/kunmap from generic helpers
The pages in compressed_pages are not from highmem anymore so we can
drop the mapping for checksum calculation and inline extent.

Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-23 13:19:00 +02:00
Christoph Hellwig
a6d3d49587 iomap: switch __iomap_dio_rw to use iomap_iter
Switch __iomap_dio_rw to use iomap_iter.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-08-16 21:26:33 -07:00
NeilBrown
3f79f6f624 btrfs: prevent rename2 from exchanging a subvol with a directory from different parents
Cross-rename lacks a check when that would prevent exchanging a
directory and subvolume from different parent subvolume. This causes
data inconsistencies and is caught before commit by tree-checker,
turning the filesystem to read-only.

Calling the renameat2 with RENAME_EXCHANGE flags like

  renameat2(AT_FDCWD, namesrc, AT_FDCWD, namedest, (1 << 1))

on two paths:

  namesrc = dir1/subvol1/dir2
 namedest = subvol2/subvol3

will cause key order problem with following write time tree-checker
report:

  [1194842.307890] BTRFS critical (device loop1): corrupt leaf: root=5 block=27574272 slot=10 ino=258, invalid previous key objectid, have 257 expect 258
  [1194842.322221] BTRFS info (device loop1): leaf 27574272 gen 8 total ptrs 11 free space 15444 owner 5
  [1194842.331562] BTRFS info (device loop1): refs 2 lock_owner 0 current 26561
  [1194842.338772]        item 0 key (256 1 0) itemoff 16123 itemsize 160
  [1194842.338793]                inode generation 3 size 16 mode 40755
  [1194842.338801]        item 1 key (256 12 256) itemoff 16111 itemsize 12
  [1194842.338809]        item 2 key (256 84 2248503653) itemoff 16077 itemsize 34
  [1194842.338817]                dir oid 258 type 2
  [1194842.338823]        item 3 key (256 84 2363071922) itemoff 16043 itemsize 34
  [1194842.338830]                dir oid 257 type 2
  [1194842.338836]        item 4 key (256 96 2) itemoff 16009 itemsize 34
  [1194842.338843]        item 5 key (256 96 3) itemoff 15975 itemsize 34
  [1194842.338852]        item 6 key (257 1 0) itemoff 15815 itemsize 160
  [1194842.338863]                inode generation 6 size 8 mode 40755
  [1194842.338869]        item 7 key (257 12 256) itemoff 15801 itemsize 14
  [1194842.338876]        item 8 key (257 84 2505409169) itemoff 15767 itemsize 34
  [1194842.338883]                dir oid 256 type 2
  [1194842.338888]        item 9 key (257 96 2) itemoff 15733 itemsize 34
  [1194842.338895]        item 10 key (258 12 256) itemoff 15719 itemsize 14
  [1194842.339163] BTRFS error (device loop1): block=27574272 write time tree block corruption detected
  [1194842.339245] ------------[ cut here ]------------
  [1194842.443422] WARNING: CPU: 6 PID: 26561 at fs/btrfs/disk-io.c:449 csum_one_extent_buffer+0xed/0x100 [btrfs]
  [1194842.511863] CPU: 6 PID: 26561 Comm: kworker/u17:2 Not tainted 5.14.0-rc3-git+ #793
  [1194842.511870] Hardware name: empty empty/S3993, BIOS PAQEX0-3 02/24/2008
  [1194842.511876] Workqueue: btrfs-worker-high btrfs_work_helper [btrfs]
  [1194842.511976] RIP: 0010:csum_one_extent_buffer+0xed/0x100 [btrfs]
  [1194842.512068] RSP: 0018:ffffa2c284d77da0 EFLAGS: 00010282
  [1194842.512074] RAX: 0000000000000000 RBX: 0000000000001000 RCX: ffff928867bd9978
  [1194842.512078] RDX: 0000000000000000 RSI: 0000000000000027 RDI: ffff928867bd9970
  [1194842.512081] RBP: ffff92876b958000 R08: 0000000000000001 R09: 00000000000c0003
  [1194842.512085] R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000
  [1194842.512088] R13: ffff92875f989f98 R14: 0000000000000000 R15: 0000000000000000
  [1194842.512092] FS:  0000000000000000(0000) GS:ffff928867a00000(0000) knlGS:0000000000000000
  [1194842.512095] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  [1194842.512099] CR2: 000055f5384da1f0 CR3: 0000000102fe4000 CR4: 00000000000006e0
  [1194842.512103] Call Trace:
  [1194842.512128]  ? run_one_async_free+0x10/0x10 [btrfs]
  [1194842.631729]  btree_csum_one_bio+0x1ac/0x1d0 [btrfs]
  [1194842.631837]  run_one_async_start+0x18/0x30 [btrfs]
  [1194842.631938]  btrfs_work_helper+0xd5/0x1d0 [btrfs]
  [1194842.647482]  process_one_work+0x262/0x5e0
  [1194842.647520]  worker_thread+0x4c/0x320
  [1194842.655935]  ? process_one_work+0x5e0/0x5e0
  [1194842.655946]  kthread+0x135/0x160
  [1194842.655953]  ? set_kthread_struct+0x40/0x40
  [1194842.655965]  ret_from_fork+0x1f/0x30
  [1194842.672465] irq event stamp: 1729
  [1194842.672469] hardirqs last  enabled at (1735): [<ffffffffbd1104f5>] console_trylock_spinning+0x185/0x1a0
  [1194842.672477] hardirqs last disabled at (1740): [<ffffffffbd1104cc>] console_trylock_spinning+0x15c/0x1a0
  [1194842.672482] softirqs last  enabled at (1666): [<ffffffffbdc002e1>] __do_softirq+0x2e1/0x50a
  [1194842.672491] softirqs last disabled at (1651): [<ffffffffbd08aab7>] __irq_exit_rcu+0xa7/0xd0

The corrupted data will not be written, and filesystem can be unmounted
and mounted again (all changes since the last commit will be lost).

Add the missing check for new_ino so that all non-subvolumes must reside
under the same parent subvolume. There's an exception allowing to
exchange two subvolumes from any parents as the directory representing a
subvolume is only a logical link and does not have any other structures
related to the parent subvolume, unlike files, directories etc, that
are always in the inode namespace of the parent subvolume.

Fixes: cdd1fedf82 ("btrfs: add support for RENAME_EXCHANGE and RENAME_WHITEOUT")
CC: stable@vger.kernel.org # 4.7+
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-08-16 13:33:23 +02:00
Christoph Hellwig
c7c3a6dcb1 btrfs: store a block_device in struct btrfs_ordered_extent
Store the block device instead of the gendisk in the btrfs_ordered_extent
structure instead of acquiring a reference to it later.

Note: this is from series removing bdgrab/bdput, btrfs is one of the
last users.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-07-22 15:50:15 +02:00
Naohiro Aota
abb99cfdaf btrfs: properly split extent_map for REQ_OP_ZONE_APPEND
Damien reported a test failure with btrfs/209. The test itself ran fine,
but the fsck ran afterwards reported a corrupted filesystem.

The filesystem corruption happens because we're splitting an extent and
then writing the extent twice. We have to split the extent though, because
we're creating too large extents for a REQ_OP_ZONE_APPEND operation.

When dumping the extent tree, we can see two EXTENT_ITEMs at the same
start address but different lengths.

$ btrfs inspect dump-tree /dev/nullb1 -t extent
...
   item 19 key (269484032 EXTENT_ITEM 126976) itemoff 15470 itemsize 53
           refs 1 gen 7 flags DATA
           extent data backref root FS_TREE objectid 257 offset 786432 count 1
   item 20 key (269484032 EXTENT_ITEM 262144) itemoff 15417 itemsize 53
           refs 1 gen 7 flags DATA
           extent data backref root FS_TREE objectid 257 offset 786432 count 1

The duplicated EXTENT_ITEMs originally come from wrongly split extent_map in
extract_ordered_extent(). Since extract_ordered_extent() uses
create_io_em() to split an existing extent_map, we will have
split->orig_start != split->start. Then, it will be logged with non-zero
"extent data offset". Finally, the logged entries are replayed into
a duplicated EXTENT_ITEM.

Introduce and use proper splitting function for extent_map. The function is
intended to be simple and specific usage for extract_ordered_extent() e.g.
not supporting compression case (we do not allow splitting compressed
extent_map anyway).

There was a question raised by Qu, in summary why we want to split the
extent map (and not the bio):

The problem is not the limit on the zone end, which as you mention is
the same as the block group end. The problem is that data write use zone
append (ZA) operations. ZA BIOs cannot be split so a large extent may
need to be processed with multiple ZA BIOs, While that is also true for
regular writes, the major difference is that ZA are "nameless" write
operation giving back the written sectors on completion. And ZA
operations may be reordered by the block layer (not intentionally
though). Combine both of these characteristics and you can see that the
data for a large extent may end up being shuffled when written resulting
in data corruption and the impossibility to map the extent to some start
sector.

To avoid this problem, zoned btrfs uses the principle "one data extent
== one ZA BIO". So large extents need to be split. This is unfortunate,
but we can revisit this later and optimize, e.g. merge back together the
fragments of an extent once written if they actually were written
sequentially in the zone.

Reported-by: Damien Le Moal <damien.lemoal@wdc.com>
Fixes: d22002fd37 ("btrfs: zoned: split ordered extent when bio is sent")
CC: stable@vger.kernel.org # 5.12+
CC: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-07-07 17:42:45 +02:00
David Sterba
f216562731 btrfs: compression: don't try to compress if we don't have enough pages
The early check if we should attempt compression does not take into
account the number of input pages. It can happen that there's only one
page, eg. a tail page after some ranges of the BTRFS_MAX_UNCOMPRESSED
have been processed, or an isolated page that won't be converted to an
inline extent.

The single page would be compressed but a later check would drop it
again because the result size must be at least one block shorter than
the input. That can never work with just one page.

CC: stable@vger.kernel.org # 4.4+
Signed-off-by: David Sterba <dsterba@suse.com>
2021-06-22 14:11:57 +02:00
David Sterba
1a9fd4172d btrfs: fix typos in comments
Fix typos that have snuck in since the last round. Found by codespell.

Signed-off-by: David Sterba <dsterba@suse.com>
2021-06-22 14:11:57 +02:00
Qu Wenruo
bcd77455d5 btrfs: don't clear page extent mapped if we're not invalidating the full page
[BUG]
With current btrfs subpage rw support, the following script can lead to
fs hang:

  $ mkfs.btrfs -f -s 4k $dev
  $ mount $dev -o nospace_cache $mnt
  $ fsstress -w -n 100 -p 1 -s 1608140256 -v -d $mnt

The fs will hang at btrfs_start_ordered_extent().

[CAUSE]
In above test case, btrfs_invalidate() will be called with the following
parameters:

  offset = 0 length = 53248 page dirty = 1 subpage dirty bitmap = 0x2000

Since @offset is 0, btrfs_invalidate() will try to invalidate the full
page, and finally call clear_page_extent_mapped() which will detach
subpage structure from the page.

And since the page no longer has subpage structure, the subpage dirty
bitmap will be cleared, preventing the dirty range from being written
back, thus no way to wake up the ordered extent.

[FIX]
Just follow other filesystems, only to invalidate the page if the range
covers the full page.

There are cases like truncate_setsize() which can call
btrfs_invalidatepage() with offset == 0 and length != 0 for the last
page of an inode.

Although the old code will still try to invalidate the full page, we are
still safe to just wait for ordered extent to finish.
So it shouldn't cause extra problems.

Tested-by: Ritesh Harjani <riteshh@linux.ibm.com> # [ppc64]
Tested-by: Anand Jain <anand.jain@oracle.com> # [aarch64]
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-06-21 15:19:10 +02:00
Qu Wenruo
2d8ec40ee4 btrfs: make btrfs_page_mkwrite() to be subpage compatible
Only set_page_dirty() and SetPageUptodate() is not subpage compatible.
Convert them to subpage helpers, so that __extent_writepage_io() can
submit page content correctly.

Tested-by: Ritesh Harjani <riteshh@linux.ibm.com> # [ppc64]
Tested-by: Anand Jain <anand.jain@oracle.com> # [aarch64]
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-06-21 15:19:10 +02:00
Qu Wenruo
6c9ac8be45 btrfs: make btrfs_truncate_block() to be subpage compatible
btrfs_truncate_block() itself is already mostly subpage compatible, the
only missing part is the page dirtying code.

Currently if we have a sector that needs to be truncated, we set the
sector aligned range delalloc, then set the full page dirty.

The problem is, current subpage code requires subpage dirty bit to be
set, or __extent_writepage_io() won't submit bio, thus leads to ordered
extent never to finish.

So this patch will make btrfs_truncate_block() to call
btrfs_page_set_dirty() helper to replace set_page_dirty() to fix the
problem.

Tested-by: Ritesh Harjani <riteshh@linux.ibm.com> # [ppc64]
Tested-by: Anand Jain <anand.jain@oracle.com> # [aarch64]
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-06-21 15:19:10 +02:00
Qu Wenruo
d2a9106448 btrfs: make btrfs_set_range_writeback() subpage compatible
Function btrfs_set_range_writeback() currently just sets the page
writeback unconditionally.

Change it to call the subpage helper so that we can handle both cases
well.

Since the subpage helpers needs btrfs_fs_info, also change the parameter
to accept btrfs_inode.

Tested-by: Ritesh Harjani <riteshh@linux.ibm.com> # [ppc64]
Tested-by: Anand Jain <anand.jain@oracle.com> # [aarch64]
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-06-21 15:19:10 +02:00
Qu Wenruo
4750af3bbe btrfs: prevent extent_clear_unlock_delalloc() to unlock page not locked by __process_pages_contig()
In cow_file_range(), after we have succeeded creating an inline extent,
we unlock the page with extent_clear_unlock_delalloc() by passing
locked_page == NULL.

For sectorsize == PAGE_SIZE case, this is just making the page lock and
unlock harder to grab.

But for incoming subpage case, it can be a big problem.

For incoming subpage case, page locking have two entry points:

- __process_pages_contig()
  In that case, we know exactly the range we want to lock (which only
  requires sector alignment).
  To handle the subpage requirement, we introduce btrfs_subpage::writers
  to page::private, and will update it in __process_pages_contig().

- Other directly lock/unlock_page() call sites
  Those won't touch btrfs_subpage::writers at all.

This means, page locked by __process_pages_contig() can only be unlocked
by __process_pages_contig().
Thankfully we already have the existing infrastructure in the form of
@locked_page in various call sites.

Unfortunately, extent_clear_unlock_delalloc() in cow_file_range() after
creating an inline extent is the exception.
It intentionally call extent_clear_unlock_delalloc() with locked_page ==
NULL, to also unlock current page (and clear its dirty/writeback bits).

To co-operate with incoming subpage modifications, and make the page
lock/unlock pair easier to understand, this patch will still call
extent_clear_unlock_delalloc() with locked_page, and only unlock the
page in __extent_writepage().

Tested-by: Ritesh Harjani <riteshh@linux.ibm.com> # [ppc64]
Tested-by: Anand Jain <anand.jain@oracle.com> # [aarch64]
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-06-21 15:19:10 +02:00
Qu Wenruo
b945a4637e btrfs: make page Ordered bit to be subpage compatible
This involves the following modification:

- Ordered extent creation
  This is done in process_one_page(), now PAGE_SET_ORDERED will call
  subpage helper to do the work.

- endio functions
  This is done in btrfs_mark_ordered_io_finished().

- btrfs_invalidatepage()

- btrfs_cleanup_ordered_extents()
  Use the subpage page helper, and add an extra branch to exit if the
  locked page have covered the full range.

Now the usage of page Ordered flag for ordered extent accounting is fully
subpage compatible.

Tested-by: Ritesh Harjani <riteshh@linux.ibm.com> # [ppc64]
Tested-by: Anand Jain <anand.jain@oracle.com> # [aarch64]
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-06-21 15:19:10 +02:00
Qu Wenruo
968f2566ad btrfs: fix hang when run_delalloc_range() failed
[BUG]
When running subpage preparation patches on x86, btrfs/125 will hang
forever with one ordered extent never finished.

[CAUSE]
The test case btrfs/125 itself will always fail as the fix is never merged.

When the test fails at balance, btrfs needs to cleanup the ordered
extent in btrfs_cleanup_ordered_extents() for data reloc inode.

The problem is in the sequence how we cleanup the page Order bit.

Currently it works like:

  btrfs_cleanup_ordered_extents()
  |- find_get_page();
  |- btrfs_page_clear_ordered(page);
  |  Now the page doesn't have Ordered bit anymore.
  |  !!! This also includes the first (locked) page !!!
  |
  |- offset += PAGE_SIZE
  |  This is to skip the first page
  |- __endio_write_update_ordered()
     |- btrfs_mark_ordered_io_finished(NULL)
        Except the first page, all ordered extents are finished.

Then the locked page is cleaned up in __extent_writepage():

  __extent_writepage()
  |- If (PageError(page))
  |- end_extent_writepage()
     |- btrfs_mark_ordered_io_finished(page)
        |- if (btrfs_test_page_ordered(page))
        |-  !!! The page gets skipped !!!
            The ordered extent is not decreased as the page doesn't
            have ordered bit anymore.

This leaves the ordered extent with bytes_left == sectorsize, thus never
finish.

[FIX]
The fix is to ensure we never clear page Ordered bit without running the
ordered extent accounting.

Here we choose to skip the locked page in
btrfs_cleanup_ordered_extents() so that later end_extent_writepage() can
properly finish the ordered extent.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-06-21 15:19:09 +02:00
Qu Wenruo
f57ad93735 btrfs: rename PagePrivate2 to PageOrdered inside btrfs
Inside btrfs we use Private2 page status to indicate we have an ordered
extent with pending IO for the sector.

But the page status name, Private2, tells us nothing about the bit
itself, so this patch will rename it to Ordered.
And with extra comment about the bit added, so reader who is still
uncertain about the page Ordered status, will find the comment pretty
easily.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2021-06-21 15:19:09 +02:00