Commit Graph

44879 Commits

Author SHA1 Message Date
Trond Myklebust
651b0e7029 NFS: Do not aggressively cache file attributes in the case of O_DIRECT
A file that is open for O_DIRECT is by definition not obeying
close-to-open cache consistency semantics, so let's not cache
the attributes too aggressively either.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-07-05 19:11:06 -04:00
Trond Myklebust
be527494e0 NFS: Remove unused function nfs_revalidate_mapping_protected()
Clean up...

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-07-05 19:11:05 -04:00
Trond Myklebust
f508d46ae4 NFS: Remove redundant waits for O_DIRECT in fsync() and write_begin()
We're now waiting immediately after taking the locks, so waiting
in fsync() and write_begin() is either redundant or potentially
subject to livelock (if not holding the lock).

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-07-05 19:11:05 -04:00
Trond Myklebust
f7b5c340ac NFS: Cleanup nfs_direct_complete()
There is only one caller that sets the "write" argument to true,
so just move the call to nfs_zap_mapping() and get rid of the
now redundant argument.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-07-05 19:11:04 -04:00
Trond Myklebust
a5864c999d NFS: Do not serialise O_DIRECT reads and writes
Allow dio requests to be scheduled in parallel, but ensuring that they
do not conflict with buffered I/O.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-07-05 19:11:04 -04:00
Trond Myklebust
18290650b1 NFS: Move buffered I/O locking into nfs_file_write()
Preparation for the patch that de-serialises O_DIRECT reads and
writes.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-07-05 19:11:03 -04:00
Trond Myklebust
89698b24d2 NFS Cleanup: move call to generic_write_checks() into fs/nfs/direct.c
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-07-05 19:11:03 -04:00
Trond Myklebust
2f3c7d87a3 NFS: Remove racy size manipulations in O_DIRECT
On success, the RPC callbacks will ensure that we make the appropriate calls
to nfs_writeback_update_inode()

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-07-05 19:11:02 -04:00
Trond Myklebust
a5314a7492 NFS: Ensure we reset the write verifier 'committed' value on resend.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-07-05 19:11:02 -04:00
Trond Myklebust
8fc3c38627 NFS: Fix O_DIRECT verifier problems
We should not be interested in looking at the value of the stable field,
since that could take any value.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-07-05 19:11:01 -04:00
Trond Myklebust
6712007734 pNFS: pnfs_layoutcommit_outstanding() is no longer used when !CONFIG_NFS_V4_1
Cleanup...

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-07-05 19:11:01 -04:00
Trond Myklebust
ac46bd374c pNFS: Ensure we layoutcommit before revalidating attributes
If we need to update the cached attributes, then we'd better make
sure that we also layoutcommit first. Otherwise, the server may have stale
attributes.

Prior to this patch, the revalidation code tried to "fix" this problem by
simply disabling attributes that would be affected by the layoutcommit.
That approach breaks nfs_writeback_check_extend(), leading to a file size
corruption.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-07-05 19:08:27 -04:00
Trond Myklebust
2e18d4d822 pNFS: Files and flexfiles always need to commit before layoutcommit
So ensure that we mark the layout for commit once the write is done,
and then ensure that the commit to ds is finished before sending
layoutcommit.

Note that by doing this, we're able to optimise away the commit
for the case of servers that don't need layoutcommit in order to
return updated attributes.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-07-05 19:08:01 -04:00
Trond Myklebust
bc28e1c2e3 pNFS/flexfiles: Clean up calls to pnfs_set_layoutcommit()
Let's just have one place where we check ff_layout_need_layoutcommit().

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-07-05 18:52:26 -04:00
Trond Myklebust
c001c87a63 pNFS/flexfiles: Fix layoutcommit after a commit to DS
We should always do a layoutcommit after commit to DS, except if
the layout segment we're using has set FF_FLAGS_NO_LAYOUTCOMMIT.

Fixes: d67ae825a5 ("pnfs/flexfiles: Add the FlexFile Layout Driver")
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-07-05 18:52:26 -04:00
Trond Myklebust
73e6c5d854 pNFS/files: Fix layoutcommit after a commit to DS
According to the errata
https://www.rfc-editor.org/errata_search.php?rfc=5661&eid=2751
we should always send layout commit after a commit to DS.

Fixes: bc7d4b8fd0 ("nfs/filelayout: set layoutcommit...")
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-07-05 18:52:25 -04:00
Trond Myklebust
4f52b6bb8c NFS: Don't call COMMIT in ->releasepage()
While COMMIT has the potential to free up a lot of memory that is being
taken by unstable writes, it isn't guaranteed to free up this particular
page. Also, calling fsync() on the server is expensive and so we want to
do it in a more controlled fashion, rather than have it triggered at
random by the VM.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-06-22 09:59:44 -04:00
Trond Myklebust
93761d9863 NFS: Don't hold the inode lock across fsync()
Commits are no longer required to be serialised.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-06-22 09:59:43 -04:00
Trond Myklebust
811ed92ecc NFS: writepage of a single page should not be synchronous
It is almost always better to wait for more so that we can issue a
bulk commit.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-06-22 09:59:43 -04:00
Trond Myklebust
6b56a89833 NFS: Kill NFS_INO_NFS_INO_FLUSHING: it is a performance killer
filemap_datawrite() and friends already deal just fine with livelock.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-06-22 09:59:42 -04:00
Trond Myklebust
ca0daa277a NFS: Cache aggressively when file is open for writing
Unless the user is using file locking, we must assume close-to-open
cache consistency when the file is open for writing. Adjust the
caching algorithm so that it does not clear the cache on out-of-order
writes and/or attribute revalidations.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-06-22 09:59:42 -04:00
Trond Myklebust
57b691819e NFS: Cache access checks more aggressively
If an attribute revalidation fails, then we already know that we'll
zap the access cache. If, OTOH, the inode isn't changing, there should
be no need to eject access calls just because they are old.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-06-15 16:36:01 -04:00
Trond Myklebust
38512aa98a NFS: Don't flush caches for a getattr that races with writeback
If there were outstanding writes then chalk up the unexpected change
attribute on the server to them.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
2016-06-13 12:36:02 -04:00
Linus Torvalds
3d0f0b6a55 Merge branch 'for-linus-4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs fixes from Chris Mason:
 "Has some fixes and some new self tests for btrfs.  The self tests are
  usually disabled in the .config file (unless you're doing btrfs dev
  work), and this bunch is meant to find problems with the 64K page size
  patches.

  Jeff has a patch to help people see if they are using the hardware
  assist crc32c module, which really helps us nail down problems when
  people ask why crcs are using so much CPU.

  Otherwise, it's small fixes"

* 'for-linus-4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  Btrfs: self-tests: Fix extent buffer bitmap test fail on BE system
  Btrfs: self-tests: Fix test_bitmaps fail on 64k sectorsize
  Btrfs: self-tests: Use macros instead of constants and add missing newline
  Btrfs: self-tests: Support testing all possible sectorsizes and nodesizes
  Btrfs: self-tests: Execute page straddling test only when nodesize < PAGE_SIZE
  btrfs: advertise which crc32c implementation is being used at module load
  Btrfs: add validadtion checks for chunk loading
  Btrfs: add more validation checks for superblock
  Btrfs: clear uptodate flags of pages in sys_array eb
  Btrfs: self-tests: Support non-4k page size
  Btrfs: Fix integer overflow when calculating bytes_per_bitmap
  Btrfs: test_check_exists: Fix infinite loop when searching for free space entries
  Btrfs: end transaction if we abort when creating uuid root
  btrfs: Use __u64 in exported linux/btrfs.h.
2016-06-10 14:13:27 -07:00
Linus Torvalds
f5364c150a Merge branch 'stacking-fixes' (vfs stacking fixes from Jann)
Merge filesystem stacking fixes from Jann Horn.

* emailed patches from Jann Horn <jannh@google.com>:
  sched: panic on corrupted stack end
  ecryptfs: forbid opening files without mmap handler
  proc: prevent stacking filesystems on top
2016-06-10 12:10:02 -07:00
Jann Horn
2f36db7100 ecryptfs: forbid opening files without mmap handler
This prevents users from triggering a stack overflow through a recursive
invocation of pagefault handling that involves mapping procfs files into
virtual memory.

Signed-off-by: Jann Horn <jannh@google.com>
Acked-by: Tyler Hicks <tyhicks@canonical.com>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-06-10 12:09:43 -07:00
Jann Horn
e54ad7f1ee proc: prevent stacking filesystems on top
This prevents stacking filesystems (ecryptfs and overlayfs) from using
procfs as lower filesystem.  There is too much magic going on inside
procfs, and there is no good reason to stack stuff on top of procfs.

(For example, procfs does access checks in VFS open handlers, and
ecryptfs by design calls open handlers from a kernel thread that doesn't
drop privileges or so.)

Signed-off-by: Jann Horn <jannh@google.com>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-06-10 12:09:43 -07:00
Chris Mason
719da39a61 Merge branch 'misc-fixes-4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux into for-linus-4.7 2016-06-08 14:36:12 -07:00
Chris Mason
4c52990080 Merge branch 'for-chris' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux into for-linus-4.7 2016-06-08 14:35:11 -07:00
Linus Torvalds
c8ae067f26 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs fixes from Al Viro:
 "Fixes for crap of assorted ages: EOPENSTALE one is 4.2+, autofs one is
  4.6, d_walk - 3.2+.

  The atomic_open() and coredump ones are regressions from this window"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  coredump: fix dumping through pipes
  fix a regression in atomic_open()
  fix d_walk()/non-delayed __d_free() race
  autofs braino fix for do_last()
  fix EOPENSTALE bug in do_last()
2016-06-07 20:41:36 -07:00
Mateusz Guzik
1607f09c22 coredump: fix dumping through pipes
The offset in the core file used to be tracked with ->written field of
the coredump_params structure. The field was retired in favour of
file->f_pos.

However, ->f_pos is not maintained for pipes which leads to breakage.

Restore explicit tracking of the offset in coredump_params. Introduce
->pos field for this purpose since ->written was already reused.

Fixes: a008393951 ("get rid of coredump_params->written").

Reported-by: Zbigniew Jędrzejewski-Szmek <zbyszek@in.waw.pl>
Signed-off-by: Mateusz Guzik <mguzik@redhat.com>
Reviewed-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-06-07 22:07:09 -04:00
Al Viro
a01e718f72 fix a regression in atomic_open()
open("/foo/no_such_file", O_RDONLY | O_CREAT) on should fail with
EACCES when /foo is not writable; failing with ENOENT is obviously
wrong.  That got broken by a braino introduced when moving the
creat_error logics from atomic_open() to lookup_open().  Easy to
fix, fortunately.

Spotted-by: "Yan, Zheng" <ukernel@gmail.com>
Tested-by: "Yan, Zheng" <ukernel@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-06-07 21:53:51 -04:00
Al Viro
3d56c25e3b fix d_walk()/non-delayed __d_free() race
Ascend-to-parent logics in d_walk() depends on all encountered child
dentries not getting freed without an RCU delay.  Unfortunately, in
quite a few cases it is not true, with hard-to-hit oopsable race as
the result.

Fortunately, the fix is simiple; right now the rule is "if it ever
been hashed, freeing must be delayed" and changing it to "if it
ever had a parent, freeing must be delayed" closes that hole and
covers all cases the old rule used to cover.  Moreover, pipes and
sockets remain _not_ covered, so we do not introduce RCU delay in
the cases which are the reason for having that delay conditional
in the first place.

Cc: stable@vger.kernel.org # v3.2+ (and watch out for __d_materialise_dentry())
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-06-07 21:26:55 -04:00
Eric W. Biederman
d71ed6c930 mnt: fs_fully_visible test the proper mount for MNT_LOCKED
MNT_LOCKED implies on a child mount implies the child is locked to the
parent.  So while looping through the children the children should be
tested (not their parent).

Typically an unshare of a mount namespace locks all mounts together
making both the parent and the slave as locked but there are a few
corner cases where other things work.

Cc: stable@vger.kernel.org
Fixes: ceeb0e5d39 ("vfs: Ignore unlocked mounts in fs_fully_visible")
Reported-by: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2016-06-06 20:52:03 -05:00
Eric W. Biederman
97c1df3e54 mnt: If fs_fully_visible fails call put_filesystem.
Add this trivial missing error handling.

Cc: stable@vger.kernel.org
Fixes: 1b852bceb0 ("mnt: Refactor the logic for mounting sysfs and proc in a user namespace")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2016-06-06 20:48:31 -05:00
Feifei Xu
34b3e6c92a Btrfs: self-tests: Fix extent buffer bitmap test fail on BE system
In __test_eb_bitmaps(), we write random data to a bitmap. Then copy
the bitmap to another bitmap that resides inside an extent buffer.
Later we verify the values of corresponding bits in the bitmap and the
bitmap inside the extent buffer. However, extent_buffer_test_bit()
reads in byte granularity while test_bit() reads in unsigned long
granularity. Hence we end up comparing wrong bits on big-endian
systems such as ppc64. This commit fixes the issue by reading the
bitmap in byte granularity.

Reviewed-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Signed-off-by: Feifei Xu <xufeifei@linux.vnet.ibm.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-06-06 17:17:12 +02:00
Feifei Xu
36b3dc05b4 Btrfs: self-tests: Fix test_bitmaps fail on 64k sectorsize
With 64K sectorsize, 1G sized block group cannot span across bitmaps.
To execute test_bitmaps() function, this commit allocates
"BITS_PER_BITMAP * sectorsize + PAGE_SIZE" sized block group.

Reviewed-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Signed-off-by: Feifei Xu <xufeifei@linux.vnet.ibm.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-06-06 17:17:12 +02:00
Feifei Xu
ef9f2db365 Btrfs: self-tests: Use macros instead of constants and add missing newline
This commit replaces numerical constants with appropriate
preprocessor macros.

Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Signed-off-by: Feifei Xu <xufeifei@linux.vnet.ibm.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-06-06 17:17:12 +02:00
Feifei Xu
d94f43b4c6 Btrfs: self-tests: Support testing all possible sectorsizes and nodesizes
To test all possible sectorsizes, this commit adds a sectorsize
array. This commit executes the tests for all possible sectorsizes and
nodesizes.

Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Signed-off-by: Feifei Xu <xufeifei@linux.vnet.ibm.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-06-06 17:17:12 +02:00
Feifei Xu
ed9e4afdb0 Btrfs: self-tests: Execute page straddling test only when nodesize < PAGE_SIZE
On ppc64, PAGE_SIZE is 64k which is same as BTRFS_MAX_METADATA_BLOCKSIZE.
In such a scenario, we will never be able to have an extent buffer
containing more than one page. Hence in such cases this commit does not
execute the page straddling tests.

Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Feifei Xu <xufeifei@linux.vnet.ibm.com>
Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-06-06 17:17:11 +02:00
Jeff Mahoney
5f9e1059d9 btrfs: advertise which crc32c implementation is being used at module load
Since several architectures support hardware-accelerated crc32c
calculation, it would be nice to confirm that btrfs is actually using it.

We can see an elevated use count for the module, but it doesn't actually
show who the users are.  This patch simply prints the name of the driver
after successfully initializing the shash.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
[ added a helper and used in module load-time message ]
Signed-off-by: David Sterba <dsterba@suse.com>
2016-06-06 14:08:28 +02:00
Liu Bo
e06cd3dd7c Btrfs: add validadtion checks for chunk loading
To prevent fuzzed filesystem images from panic the whole system,
we need various validation checks to refuse to mount such an image
if btrfs finds any invalid value during loading chunks, including
both sys_array and regular chunks.

Note that these checks may not be sufficient to cover all corner cases,
feel free to add more checks.

Reported-by: Vegard Nossum <vegard.nossum@oracle.com>
Reported-by: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-06-06 10:57:09 +02:00
Liu Bo
99e3ecfcb9 Btrfs: add more validation checks for superblock
This adds validation checks for super_total_bytes, super_bytes_used and
super_stripesize, super_num_devices.

Reported-by: Vegard Nossum <vegard.nossum@oracle.com>
Reported-by: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-06-06 10:41:53 +02:00
Liu Bo
d865177a5e Btrfs: clear uptodate flags of pages in sys_array eb
We set uptodate flag to pages in the temporary sys_array eb,
but do not clear the flag after free eb.  As the special
btree inode may still hold a reference on those pages, the
uptodate flag can remain alive in them.

If btrfs_super_chunk_root has been intentionally changed to the
offset of this sys_array eb, reading chunk_root will read content
of sys_array and it will skip our beautiful checks in
btree_readpage_end_io_hook() because of
"pages of eb are uptodate => eb is uptodate"

This adds the 'clear uptodate' part to force it to read from disk.

Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-06-06 10:14:40 +02:00
Eric W. Biederman
eedf265aa0 devpts: Make each mount of devpts an independent filesystem.
The /dev/ptmx device node is changed to lookup the directory entry "pts"
in the same directory as the /dev/ptmx device node was opened in.  If
there is a "pts" entry and that entry is a devpts filesystem /dev/ptmx
uses that filesystem.  Otherwise the open of /dev/ptmx fails.

The DEVPTS_MULTIPLE_INSTANCES configuration option is removed, so that
userspace can now safely depend on each mount of devpts creating a new
instance of the filesystem.

Each mount of devpts is now a separate and equal filesystem.

Reserved ttys are now available to all instances of devpts where the
mounter is in the initial mount namespace.

A new vfs helper path_pts is introduced that finds a directory entry
named "pts" in the directory of the passed in path, and changes the
passed in path to point to it.  The helper path_pts uses a function
path_parent_directory that was factored out of follow_dotdot.

In the implementation of devpts:
 - devpts_mnt is killed as it is no longer meaningful if all mounts of
   devpts are equal.
 - pts_sb_from_inode is replaced by just inode->i_sb as all cached
   inodes in the tty layer are now from the devpts filesystem.
 - devpts_add_ref is rolled into the new function devpts_ptmx.  And the
   unnecessary inode hold is removed.
 - devpts_del_ref is renamed devpts_release and reduced to just a
   deacrivate_super.
 - The newinstance mount option continues to be accepted but is now
   ignored.

In devpts_fs.h definitions for when !CONFIG_UNIX98_PTYS are removed as
they are never used.

Documentation/filesystems/devices.txt is updated to describe the current
situation.

This has been verified to work properly on openwrt-15.05, centos5,
centos6, centos7, debian-6.0.2, debian-7.9, debian-8.2, ubuntu-14.04.3,
ubuntu-15.10, fedora23, magia-5, mint-17.3, opensuse-42.1,
slackware-14.1, gentoo-20151225 (13.0?), archlinux-2015-12-01.  With the
caveat that on centos6 and on slackware-14.1 that there wind up being
two instances of the devpts filesystem mounted on /dev/pts, the lower
copy does not end up getting used.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Greg KH <greg@kroah.com>
Cc: Peter Hurley <peter@hurleysoftware.com>
Cc: Peter Anvin <hpa@zytor.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Serge Hallyn <serge.hallyn@ubuntu.com>
Cc: Willy Tarreau <w@1wt.eu>
Cc: Aurelien Jarno <aurelien@aurel32.net>
Cc: One Thousand Gnomes <gnomes@lxorguk.ukuu.org.uk>
Cc: Jann Horn <jann@thejh.net>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Florian Weimer <fw@deneb.enyo.de>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-06-05 10:36:01 -07:00
Al Viro
e6ec03a25f autofs braino fix for do_last()
It's an analogue of commit 7500c38a (fix the braino in "namei:
massage lookup_slow() to be usable by lookup_one_len_unlocked()").
The same problem (->lookup()-returned unhashed negative dentry
just might be an autofs one with ->d_manage() that would wait
until the daemon makes it positive) applies in do_last() - we
need to do follow_managed() first.

Fortunately, remaining callers of follow_managed() are OK - only
autofs has that weirdness (negative dentry that does not mean
an instant -ENOENT)) and autofs never has its negative dentries
hashed, so we can't pick one from a dcache lookup.

->d_manage() is a bloody mess ;-/

Cc: stable@vger.kernel.org # v4.6
Spotted-by: Ian Kent <raven@themaw.net>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-06-05 00:23:09 -04:00
Linus Torvalds
b2d5ad8223 Merge branch 'for-linus-4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs fixes from Chris Mason:
 "The important part of this pull is Filipe's set of fixes for btrfs
  device replacement.  Filipe fixed a few issues seen on the list and a
  number he found on his own"

* 'for-linus-4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  Btrfs: deal with duplciates during extent_map insertion in btrfs_get_extent
  Btrfs: fix race between device replace and read repair
  Btrfs: fix race between device replace and discard
  Btrfs: fix race between device replace and chunk allocation
  Btrfs: fix race setting block group back to RW mode during device replace
  Btrfs: fix unprotected assignment of the left cursor for device replace
  Btrfs: fix race setting block group readonly during device replace
  Btrfs: fix race between device replace and block group removal
  Btrfs: fix race between readahead and device replace/removal
2016-06-04 11:56:28 -07:00
Al Viro
fac7d1917d fix EOPENSTALE bug in do_last()
EOPENSTALE occuring at the last component of a trailing symlink ends up
with do_last() retrying its lookup.  After the symlink body has been
discarded.  The thing is, all this retry_lookup logics in there is not
needed at all - the upper layers will do the right thing if we simply
return that -EOPENSTALE as we would with any other error.  Trying to
microoptimize in do_last() is a lot of headache for no good reason.

Cc: stable@vger.kernel.org # v4.2+
Tested-by: Oleg Drokin <green@linuxhacker.ru>
Reviewed-and-Tested-by: Jeff Layton <jlayton@poochiereds.net>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-06-04 11:59:04 -04:00
Chris Mason
8dff9c8534 Btrfs: deal with duplciates during extent_map insertion in btrfs_get_extent
When dealing with inline extents, btrfs_get_extent will incorrectly try
to insert a duplicate extent_map.  The dup hits -EEXIST from
add_extent_map, but then we try to merge with the existing one and end
up trying to insert a zero length extent_map.

This actually works most of the time, except when there are extent maps
past the end of the inline extent.  rocksdb will trigger this sometimes
because it preallocates an extent and then truncates down.

Josef made a script to trigger with xfs_io:

	#!/bin/bash

	xfs_io -f -c "pwrite 0 1000" inline
	xfs_io -c "falloc -k 4k 1M" inline
	xfs_io -c "pread 0 1000" -c "fadvise -d 0 1000" -c "pread 0 1000" inline
	xfs_io -c "fadvise -d 0 1000" inline
	cat inline

You'll get EIOs trying to read inline after this because add_extent_map
is returning EEXIST

Signed-off-by: Chris Mason <clm@fb.com>
2016-06-03 12:32:34 -07:00
Feifei Xu
b9ef22dedd Btrfs: self-tests: Support non-4k page size
self-tests code assumes 4k as the sectorsize and nodesize. This commit
fix hardcoded 4K. Enables the self-tests code to be executed on non-4k
page sized systems (e.g. ppc64).

Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Feifei Xu <xufeifei@linux.vnet.ibm.com>
Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-06-02 19:23:14 +02:00