Before this patch, btrfs qgroup is mixing per-transcation meta rsv with
preallocated meta rsv, making it quite easy to underflow qgroup meta
reservation.
Since we have the new qgroup meta rsv types, apply it to delalloc
reservation.
Now for delalloc, most of its reserved space will use META_PREALLOC qgroup
rsv type.
And for callers reducing outstanding extent like btrfs_finish_ordered_io(),
they will convert corresponding META_PREALLOC reservation to
META_PERTRANS.
This is mainly due to the fact that current qgroup numbers will only be
updated in btrfs_commit_transaction(), that's to say if we don't keep
such placeholder reservation, we can exceed qgroup limitation.
And for callers freeing outstanding extent in error handler, we will
just free META_PREALLOC bytes.
This behavior makes callers of btrfs_qgroup_release_meta() or
btrfs_qgroup_convert_meta() to be aware of which type they are.
So in this patch, btrfs_delalloc_release_metadata() and its callers get
an extra parameter to info qgroup to do correct meta convert/release.
The good news is, even we use the wrong type (convert or free), it won't
cause obvious bug, as prealloc type is always in good shape, and the
type only affects how per-trans meta is increased or not.
So the worst case will be at most metadata limitation can be sometimes
exceeded (no convert at all) or metadata limitation is reached too soon
(no free at all).
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
btrfs_orphan_add() has had this case commented out since it was first
introduced in commit d68fc57b7e ("Btrfs: Metadata reservation for
orphan inodes"). Most of the orphan cleanup code has been rewritten
since then, so it's safe to say that this code isn't needed.
Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
[ switch to bool ]
Signed-off-by: David Sterba <dsterba@suse.com>
Added in 38c227d87c ("Btrfs: snapshot-aware defrag") but subsequently
made redundant by 0b246afa62 ("btrfs: root->fs_info cleanup, add
fs_info convenience variables").
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The current implementation of btrfs_page_exists_in_range() gives the
wrong answer if the workingset code has stored a shadow entry in the
page cache. The filemap_range_has_page() function does not have this
problem, and it's shared code, so use it instead.
eigned-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Previously, btrfs_inode_by_name() returned 0 which left caller to check
objectid of location even location if the type was invalid.
Let btrfs_inode_by_name() return -EUCLEAN if a corrupted location of a
dir entry is found. Removal of label out_err also simplifies the
function.
Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ drop unlikely ]
Signed-off-by: David Sterba <dsterba@suse.com>
This argument is always set to the root of the inode, which is also
passed. So let's get a reference inside the function and simplify
the arg list.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
When we truncate a file to the same size and that size is not aligned
with the sector size, we end up triggering writeback (and wait for it to
complete) of the last page. This is unncessary as we can not have delayed
allocation beyond the inode's i_size and the goal of truncating a file
to its own size is to discard prealloc extents (allocated via the
fallocate(2) system call). Besides the unnecessary IO start and wait, it
also breaks the oppurtunity for larger contiguous extents on disk, as
before the last dirty page there might be other dirty pages.
This scenario is probably not very common in general, however it is
common for btrfs receive implementations because currently the send
stream always issues a truncate operation for each processed inode as
the last operation for that inode (this truncate operation is not
always needed and the send implementation will be addressed to avoid
them).
So improve this by not starting and waiting for writeback of the inode's
last page when we are truncating to exactly the same size.
The following script was used to quickly measure the time a receive
operation takes:
$ cat test_send.sh
#!/bin/bash
SRC_DEV=/dev/sdc
DST_DEV=/dev/sdd
SRC_MNT=/mnt/sdc
DST_MNT=/mnt/sdd
mkfs.btrfs -f $SRC_DEV >/dev/null
mkfs.btrfs -f $DST_DEV >/dev/null
mount $SRC_DEV $SRC_MNT
mount $DST_DEV $DST_MNT
echo "Creating source filesystem"
for ((t = 0; t < 10; t++)); do
(
for ((i = 1; i <= 20000; i++)); do
xfs_io -f -c "pwrite -S 0xab 0 5000" \
$SRC_MNT/file_$i > /dev/null
done
) &
worker_pids[$t]=$!
done
wait ${worker_pids[@]}
echo "Creating and sending snapshot"
btrfs subvolume snapshot -r $SRC_MNT $SRC_MNT/snap1 >/dev/null
/usr/bin/time -f "send took %e seconds" \
btrfs send -f $SRC_MNT/send_file $SRC_MNT/snap1
/usr/bin/time -f "receive took %e seconds" \
btrfs receive -f $SRC_MNT/send_file $DST_MNT
umount $SRC_MNT
umount $DST_MNT
The results for 5 runs were the following:
* Without this change
average receive time was 26.49 seconds
standard deviation of 2.53 seconds
* With this change
average receive time was 12.51 seconds
standard deviation of 0.32 seconds
Reported-by: Robbie Ko <robbieko@synology.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Using any kind of memory barriers around atomic operations which have
a return value is redundant, since those operations themselves are
fully ordered. atomic_t.txt states:
- RMW operations that have a return value are fully ordered;
Fully ordered primitives are ordered against everything prior and
everything subsequent. Therefore a fully ordered primitive is like
having an smp_mb() before and an smp_mb() after the primitive.
Given this let's replace the extra memory barriers with comments.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The __cold functions are placed to a special section, as they're
expected to be called rarely. This could help i-cache prefetches or help
compiler to decide which branches are more/less likely to be taken
without any other annotations needed.
Though we can't add more __exit annotations, it's still possible to add
__cold (that's also added with __exit). That way the following function
categories are tagged:
- printf wrappers, error messages
- exit helpers
Signed-off-by: David Sterba <dsterba@suse.com>
Fstests generic/475 provides a way to fail metadata reads while
checking if checksum exists for the inode inside run_delalloc_nocow(),
and csum_exist_in_range() interprets error (-EIO) as inode having
checksum and makes its caller enter the cow path.
In case of free space inode, this ends up with a warning in
cow_file_range().
The same problem applies to btrfs_cross_ref_exist() since it may also
read metadata in between.
With this, run_delalloc_nocow() bails out when errors occur at the two
places.
cc: <stable@vger.kernel.org> v2.6.28+
Fixes: 17d217fe97 ("Btrfs: fix nodatasum handling in balancing code")
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The custom crc32 init code was introduced in
14a958e678 ("Btrfs: fix btrfs boot when compiled as built-in") to
enable using btrfs as a built-in. However, later as pointed out by
60efa5eb2e ("Btrfs: use late_initcall instead of module_init") this
wasn't enough and finally btrfs was switched to late_initcall which
comes after the generic crc32c implementation is initiliased. The
latter commit superseeded the former. Now that we don't have to
maintain our own code let's just remove it and switch to using the
generic implementation.
Despite touching a lot of files the patch is really simple. Here is the gist of
the changes:
1. Select LIBCRC32C rather than the low-level modules.
2. s/btrfs_crc32c/crc32c/g
3. replace hash.h with linux/crc32c.h
4. Move the btrfs namehash funcs to ctree.h and change the tree accordingly.
I've tested this with btrfs being both a module and a built-in and xfstest
doesn't complain.
Does seem to fix the longstanding problem of not automatically selectiong
the crc32c module when btrfs is used. Possibly there is a workaround in
dracut.
The modinfo confirms that now all the module dependencies are there:
before:
depends: zstd_compress,zstd_decompress,raid6_pq,xor,zlib_deflate
after:
depends: libcrc32c,zstd_compress,zstd_decompress,raid6_pq,xor,zlib_deflate
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ add more info to changelog from mails ]
Signed-off-by: David Sterba <dsterba@suse.com>
delayed_iput_count wa supposed to be used to implement, well, delayed
iput. The idea is that we keep accumulating the number of iputs we do
until eventually the inode is deleted. Turns out we never really
switched the delayed_iput_count from 0 to 1, hence all conditional
code relying on the value of that member being different than 0 was
never executed. This, as it turns out, didn't cause any problem due
to the simple fact that the generic inode's i_count member was always
used to count the number of iputs. So let's just remove the unused
member and all unused code. This patch essentially provides no
functional changes. While at it, also add proper documentation for
btrfs_add_delayed_iput
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ reformat comment ]
Signed-off-by: David Sterba <dsterba@suse.com>
It's not necessary to hold ->orphan_lock when checking inode's runtime
flags.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Use ASSERT to report logical error in cow_file_range(), also move it a
bit closer to when the num_bytes is derived.
The extent start could be (u64)-1 in some cases, the assert should catch
that we do not accidentally pass it to cow_file_range.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This patch deletes local variable disk_num_bytes as its value
is same as num_bytes in the function cow_file_range().
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
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Merge tag 'for-4.16-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs fixes from David Sterba:
- when NR_CPUS is large, a SRCU structure can significantly inflate
size of the main filesystem structure that would not be possible to
allocate by kmalloc, so the kvalloc fallback is used
- improved error handling
- fix endiannes when printing some filesystem attributes via sysfs,
this is could happen when a filesystem is moved between different
endianity hosts
- send fixes: the NO_HOLE mode should not send a write operation for a
file hole
- fix log replay for for special files followed by file hardlinks
- fix log replay failure after unlink and link combination
- fix max chunk size calculation for DUP allocation
* tag 'for-4.16-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
Btrfs: fix log replay failure after unlink and link combination
Btrfs: fix log replay failure after linking special file and fsync
Btrfs: send, fix issuing write op when processing hole in no data mode
btrfs: use proper endianness accessors for super_copy
btrfs: alloc_chunk: fix DUP stripe size handling
btrfs: Handle btrfs_set_extent_delalloc failure in relocate_file_extent_cluster
btrfs: handle failure of add_pending_csums
btrfs: use kvzalloc to allocate btrfs_fs_info
add_pending_csums was added as part of the new data=ordered
implementation in e6dcd2dc9c ("Btrfs: New data=ordered
implementation"). Even back then it called the btrfs_csum_file_blocks
which can fail but it never bothered handling the failure. In ENOMEM
situation this could lead to the filesystem failing to write the
checksums for a particular extent and not detect this. On read this
could lead to the filesystem erroring out due to crc mismatch. Fix it by
propagating failure from add_pending_csums and handling them.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
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Merge tag 'for-4.16-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs fixes from David Sterba:
"We have a few assorted fixes, some of them show up during fstests so I
gave them more testing"
* tag 'for-4.16-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
btrfs: Fix use-after-free when cleaning up fs_devs with a single stale device
Btrfs: fix null pointer dereference when replacing missing device
btrfs: remove spurious WARN_ON(ref->count < 0) in find_parent_nodes
btrfs: Ignore errors from btrfs_qgroup_trace_extent_post
Btrfs: fix unexpected -EEXIST when creating new inode
Btrfs: fix use-after-free on root->orphan_block_rsv
Btrfs: fix btrfs_evict_inode to handle abnormal inodes correctly
Btrfs: fix extent state leak from tree log
Btrfs: fix crash due to not cleaning up tree log block's dirty bits
Btrfs: fix deadlock in run_delalloc_nocow
This regression is introduced in
commit 3d48d9810d ("btrfs: Handle uninitialised inode eviction").
There are two problems,
a) it is ->destroy_inode() that does the final free on inode, not
->evict_inode(),
b) clear_inode() must be called before ->evict_inode() returns.
This could end up hitting BUG_ON(inode->i_state != (I_FREEING | I_CLEAR));
in evict() because I_CLEAR is set in clear_inode().
Fixes: commit 3d48d9810d ("btrfs: Handle uninitialised inode eviction")
Cc: <stable@vger.kernel.org> # v4.7-rc6+
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
@cur_offset is not set back to what it should be (@cow_start) if
btrfs_next_leaf() returns something wrong, and the range [cow_start,
cur_offset) remains locked forever.
cc: <stable@vger.kernel.org>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
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Merge tag 'for-4.16-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs updates from David Sterba:
"Features or user visible changes:
- fallocate: implement zero range mode
- avoid losing data raid profile when deleting a device
- tree item checker: more checks for directory items and xattrs
Notable fixes:
- raid56 recovery: don't use cached stripes, that could be
potentially changed and a later RMW or recovery would lead to
corruptions or failures
- let raid56 try harder to rebuild damaged data, reading from all
stripes if necessary
- fix scrub to repair raid56 in a similar way as in the case above
Other:
- cleanups: device freeing, removed some call indirections, redundant
bio_put/_get, unused parameters, refactorings and renames
- RCU list traversal fixups
- simplify mount callchain, remove recursing back when mounting a
subvolume
- plug for fsync, may improve bio merging on multiple devices
- compression heurisic: replace heap sort with radix sort, gains some
performance
- add extent map selftests, buffered write vs dio"
* tag 'for-4.16-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: (155 commits)
btrfs: drop devid as device_list_add() arg
btrfs: get device pointer from device_list_add()
btrfs: set the total_devices in device_list_add()
btrfs: move pr_info into device_list_add
btrfs: make btrfs_free_stale_devices() to match the path
btrfs: rename btrfs_free_stale_devices() arg to skip_dev
btrfs: make btrfs_free_stale_devices() argument optional
btrfs: make btrfs_free_stale_device() to iterate all stales
btrfs: no need to check for btrfs_fs_devices::seeding
btrfs: Use IS_ALIGNED in btrfs_truncate_block instead of opencoding it
Btrfs: noinline merge_extent_mapping
Btrfs: add WARN_ONCE to detect unexpected error from merge_extent_mapping
Btrfs: extent map selftest: dio write vs dio read
Btrfs: extent map selftest: buffered write vs dio read
Btrfs: add extent map selftests
Btrfs: move extent map specific code to extent_map.c
Btrfs: add helper for em merge logic
Btrfs: fix unexpected EEXIST from btrfs_get_extent
Btrfs: fix incorrect block_len in merge_extent_mapping
btrfs: Remove unused readahead spinlock
...
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Merge tag 'iversion-v4.16-1' of git://git.kernel.org/pub/scm/linux/kernel/git/jlayton/linux
Pull inode->i_version rework from Jeff Layton:
"This pile of patches is a rework of the inode->i_version field. We
have traditionally incremented that field on every inode data or
metadata change. Typically this increment needs to be logged on disk
even when nothing else has changed, which is rather expensive.
It turns out though that none of the consumers of that field actually
require this behavior. The only real requirement for all of them is
that it be different iff the inode has changed since the last time the
field was checked.
Given that, we can optimize away most of the i_version increments and
avoid dirtying inode metadata when the only change is to the i_version
and no one is querying it. Queries of the i_version field are rather
rare, so we can help write performance under many common workloads.
This patch series converts existing accesses of the i_version field to
a new API, and then converts all of the in-kernel filesystems to use
it. The last patch in the series then converts the backend
implementation to a scheme that optimizes away a large portion of the
metadata updates when no one is looking at it.
In my own testing this series significantly helps performance with
small I/O sizes. I also got this email for Christmas this year from
the kernel test robot (a 244% r/w bandwidth improvement with XFS over
DAX, with 4k writes):
https://lkml.org/lkml/2017/12/25/8
A few of the earlier patches in this pile are also flowing to you via
other trees (mm, integrity, and nfsd trees in particular)".
* tag 'iversion-v4.16-1' of git://git.kernel.org/pub/scm/linux/kernel/git/jlayton/linux: (22 commits)
fs: handle inode->i_version more efficiently
btrfs: only dirty the inode in btrfs_update_time if something was changed
xfs: avoid setting XFS_ILOG_CORE if i_version doesn't need incrementing
fs: only set S_VERSION when updating times if necessary
IMA: switch IMA over to new i_version API
xfs: convert to new i_version API
ufs: use new i_version API
ocfs2: convert to new i_version API
nfsd: convert to new i_version API
nfs: convert to new i_version API
ext4: convert to new i_version API
ext2: convert to new i_version API
exofs: switch to new i_version API
btrfs: convert to new i_version API
afs: convert to new i_version API
affs: convert to new i_version API
fat: convert to new i_version API
fs: don't take the i_lock in inode_inc_iversion
fs: new API for handling inode->i_version
ntfs: remove i_version handling
...
At this point, we know that "now" and the file times may differ, and we
suspect that the i_version has been flagged to be bumped. Attempt to
bump the i_version, and only mark the inode dirty if that actually
occurred or if one of the times was updated.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Acked-by: David Sterba <dsterba@suse.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Add a documentation blob that explains what the i_version field is, how
it is expected to work, and how it is currently implemented by various
filesystems.
We already have inode_inc_iversion. Add several other functions for
manipulating and accessing the i_version counter. For now, the
implementation is trivial and basically works the way that all of the
open-coded i_version accesses work today.
Future patches will convert existing users of i_version to use the new
API, and then convert the backend implementation to do things more
efficiently.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
No functional changes, just makes the code more readable
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
These helpers are extent map specific, move them to extent_map.c.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This is a prepare work for the following extent map selftest, which
runs tests against em merge logic.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This fixes a corner case that is caused by a race of dio write vs dio
read/write.
Here is how the race could happen.
Suppose that no extent map has been loaded into memory yet.
There is a file extent [0, 32K), two jobs are running concurrently
against it, t1 is doing dio write to [8K, 32K) and t2 is doing dio
read from [0, 4K) or [4K, 8K).
t1 goes ahead of t2 and splits em [0, 32K) to em [0K, 8K) and [8K 32K).
------------------------------------------------------
t1 t2
btrfs_get_blocks_direct() btrfs_get_blocks_direct()
-> btrfs_get_extent() -> btrfs_get_extent()
-> lookup_extent_mapping()
-> add_extent_mapping() -> lookup_extent_mapping()
# load [0, 32K)
-> btrfs_new_extent_direct()
-> btrfs_drop_extent_cache()
# split [0, 32K) and
# drop [8K, 32K)
-> add_extent_mapping()
# add [8K, 32K)
-> add_extent_mapping()
# handle -EEXIST when adding
# [0, 32K)
------------------------------------------------------
About how t2(dio read/write) runs into -EEXIST:
a) add_extent_mapping() gets -EEXIST for adding em [0, 32k),
b) search_extent_mapping() then returns [0, 8k) as the existing em,
even though start == existing->start, em is [0, 32k) so that
extent_map_end(em) > extent_map_end(existing), i.e. 32k > 8k,
c) then it goes thru merge_extent_mapping() which tries to add a [8k, 8k)
(with a length 0) and returns -EEXIST as [8k, 32k) is already in tree,
d) so btrfs_get_extent() ends up returning -EEXIST to dio read/write,
which is confusing applications.
Here I conclude all the possible situations,
1) start < existing->start
+-----------+em+-----------+
+--prev---+ | +-------------+ |
| | | | | |
+---------+ + +---+existing++ ++
+
|
+
start
2) start == existing->start
+------------em------------+
| +-------------+ |
| | | |
+ +----existing-+ +
|
|
+
start
3) start > existing->start && start < (existing->start + existing->len)
+------------em------------+
| +-------------+ |
| | | |
+ +----existing-+ +
|
|
+
start
4) start >= (existing->start + existing->len)
+-----------+em+-----------+
| +-------------+ | +--next---+
| | | | | |
+ +---+existing++ + +---------+
+
|
+
start
As we can see, it turns out that if start is within existing em (front
inclusive), then the existing em should be returned as is, otherwise,
we try our best to merge candidate em with sibling ems to form a
larger em (in order to reduce the total number of em).
Reported-by: David Vallender <david.vallender@landmark.co.uk>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
%block_len could be checked on deciding if two em are mergeable.
merge_extent_mapping() has only added the front pad if the front part
of em gets truncated, but it's possible that the end part gets
truncated.
For both compressed extent and inline extent, em->block_len is not
adjusted accordingly, and for regular extent, em->block_len always
equals to em->len, hence this sets em->block_len with em->len.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
There is no function named btrfs_get_inode_index_count.
Explanation for magic number index_cnt=2 in btrfs_new_inode() is
actually located in btrfs_set_inode_index_count().
So replace 'btrfs_get_inode_index_count' in the comment by
'btrfs_set_inode_index_count'.
Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
All callers pass either GFP_NOFS or GFP_KERNEL now, so we can sink the
parameter to the function, though we lose some of the slightly better
semantics of GFP_KERNEL in some places, it's worth cleaning up the
callchains.
Signed-off-by: David Sterba <dsterba@suse.com>
The bio is not referenced after it has been submitted and the endio is
going to consume the sole reference on successful submission. On error,
the callers of __btrfs_submit_dio_bio do invoke bio_put so we don't
leak it either.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The bio that is passsed is the newly created repair bio which already
has a reference count of 1, which is going to be consumed by the
endio routine on successful submission. On error the handler also
calls bio_put.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The tree argument passed to extent_write_full_page is referenced from
the page being passed to the same function. Since we already have
enough information to get the reference, remove the function parameter.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This function is called only from submit_compressed_extents and the
io tree being passed is always that of the inode. But we are also
passing the inode, so just move getting the io tree pointer in
extent_write_locked_range to simplify the signature.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This function was introduced by 247e743cbe ("Btrfs: Use async helpers
to deal with pages that have been improperly dirtied") and it didn't do
any error handling then. This function might very well fail in ENOMEM
situation, yet it's not handled, this could lead to inconsistent state.
So let's handle the failure by setting the mapping error bit.
Cc: stable@vger.kernel.org
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Before returning hole_em in btrfs_get_fiemap_extent we check if it's different
than null. However, by the time this null check is triggered we already know
hole_em is not null because it means it points to the em we found and it
has already been dereferenced.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
trans was statically assigned to NULL and this never changed over the
course of btrfs_get_extent. So remove any code which checks whether
trans != NULL and just hardcode the fact trans is always NULL.
Resolves-coverity-id: 112806
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
We need to call extent_range_clear_dirty_for_io()
on compression range to prevent application from changing
page content, while pages compressing.
extent_range_clear_dirty_for_io() runs on each loop iteration,
"(end - start)" can be much (up to 1024 times) bigger
then compression range (BTRFS_MAX_UNCOMPRESSED).
The start pointer is advanced each time we manage to compress part of
the range. The end pointer does not change so we could redirty the
remaining parts repeatedly.
Fix that behaviour by call extent_range_clear_dirty_for_io()
only once, the first time it happens.
This is the safest but probably not the best behaviour. Previous
iterations of the patch tried to redirty only the range that we were not
able to compress. This has been refused by David for safety reasons, the
writeout callchain is complex and there could be some path that relies
on redirtying the entire unwritten range.
Signed-off-by: Timofey Titovets <nefelim4ag@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ enhance changelog, the history and safety concerns, add comment ]
Signed-off-by: David Sterba <dsterba@suse.com>
Commit 9036c10208 ("Btrfs: update hole handling v2") added the
FLAG_VACANCY to denote holes, however there was already a consistent way
of flagging extents which represent hole - ->block_start =
EXTENT_MAP_HOLE. And also the only place where this flag is checked is
in the fiemap code, but the block_start value is also checked and every
other place in the filesystem detects holes by using block_start
value's. So remove the extra flag. This survived a full xfstest run.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
The semantics of adding_csums matches bool, 'short' was most likely used
to save space in a698d0755a ("Btrfs: add a type field for the
transaction handle").
Signed-off-by: David Sterba <dsterba@suse.com>
Due to new_inline logic, the create == 0 is always true at this
point in the code, so the create != 0 branch can be removed.
Signed-off-by: Edmund Nadolski <enadolski@suse.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
