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  1. 20 7月, 2013 2 次提交
    • A
      livelock avoidance in sget() · acfec9a5
      由 Al Viro 提交于 
      Eric Sandeen has found a nasty livelock in sget() - take a mount(2) about
to fail.  The superblock is on ->fs_supers, ->s_umount is held exclusive,
->s_active is 1.  Along comes two more processes, trying to mount the same
thing; sget() in each is picking that superblock, bumping ->s_count and
trying to grab ->s_umount.  ->s_active is 3 now.  Original mount(2)
finally gets to deactivate_locked_super() on failure; ->s_active is 2,
superblock is still ->fs_supers because shutdown will *not* happen until
->s_active hits 0.  ->s_umount is dropped and now we have two processes
chasing each other:
s_active = 2, A acquired ->s_umount, B blocked
A sees that the damn thing is stillborn, does deactivate_locked_super()
s_active = 1, A drops ->s_umount, B gets it
A restarts the search and finds the same superblock.  And bumps it ->s_active.
s_active = 2, B holds ->s_umount, A blocked on trying to get it
... and we are in the earlier situation with A and B switched places.

The root cause, of course, is that ->s_active should not grow until we'd
got MS_BORN.  Then failing ->mount() will have deactivate_locked_super()
shut the damn thing down.  Fortunately, it's easy to do - the key point
is that grab_super() is called only for superblocks currently on ->fs_supers,
so it can bump ->s_count and grab ->s_umount first, then check MS_BORN and
bump ->s_active; we must never increment ->s_count for superblocks past
->kill_sb(), but grab_super() is never called for those.

The bug is pretty old; we would've caught it by now, if not for accidental
exclusion between sget() for block filesystems; the things like cgroup or
e.g. mtd-based filesystems don't have anything of that sort, so they get
bitten.  The right way to deal with that is obviously to fix sget()...
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
      acfec9a5
    • A
      allow O_TMPFILE to work with O_WRONLY · ba57ea64
      由 Al Viro 提交于 
      Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
      ba57ea64
  3. 14 7月, 2013 3 次提交
  5. 13 7月, 2013 5 次提交
  7. 12 7月, 2013 5 次提交
    • A
      ext4: rate limit printk in buffer_io_error() · e8974c39
      由 Anatol Pomozov 提交于 
      If there are a lot of outstanding buffered IOs when a device is
taken offline (due to hardware errors etc), ext4_end_bio prints
out a message for each failed logical block. While this is desirable,
we see thousands of such lines being printed out before the
serial console gets overwhelmed, causing ext4_end_bio() wait for
the printk to complete.

This in itself isn't a disaster, except for the detail that this
function is being called with the queue lock held.
This causes any other function in the block layer
to spin on its spin_lock_irqsave while the serial console is
draining. If NMI watchdog is enabled on this machine then it
eventually comes along and shoots the machine in the head.

The end result is that losing any one disk causes the machine to
go down. This patch rate limits the printk to bandaid around the
problem.

Tested: xfstests
Change-Id: I8ab5690dcf4f3a67e78be147d45e489fdf4a88d8
Signed-off-by: NAnatol Pomozov <anatol.pomozov@gmail.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
      e8974c39
    • P
      CIFS: Fix a deadlock when a file is reopened · 689c3db4
      由 Pavel Shilovsky 提交于 
      If we request reading or writing on a file that needs to be
reopened, it causes the deadlock: we are already holding rw
semaphore for reading and then we try to acquire it for writing
in cifs_relock_file. Fix this by acquiring the semaphore for
reading in cifs_relock_file due to we don't make any changes in
locks and don't need a write access.

CC: <stable@vger.kernel.org>
Signed-off-by: NPavel Shilovsky <pshilovsky@samba.org>
Acked-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <smfrench@gmail.com>
      689c3db4
    • P
      CIFS: Reopen the file if reconnect durable handle failed · b33fcf1c
      由 Pavel Shilovsky 提交于 
      This is a follow-on patch for 8/8 patch from the durable handles
series. It fixes the problem when durable file handle timeout
expired on the server and reopen returns -ENOENT for such files.
Signed-off-by: NPavel Shilovsky <pshilovsky@samba.org>
Signed-off-by: NSteve French <smfrench@gmail.com>
      b33fcf1c
    • T
      ext4: don't show usrquota/grpquota twice in /proc/mounts · ad065dd0
      由 Theodore Ts'o 提交于 
      We now print mount options in a generic fashion in
ext4_show_options(), so we shouldn't be explicitly printing the
{usr,grp}quota options in ext4_show_quota_options().

Without this patch, /proc/mounts can look like this:

 /dev/vdb /vdb ext4 rw,relatime,quota,usrquota,data=ordered,usrquota 0 0
                                      ^^^^^^^^              ^^^^^^^^
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
Cc: stable@vger.kernel.org
      ad065dd0
    • C
      xfs: Fix the logic check for all quotas being turned off · c31ad439
      由 Chandra Seetharaman 提交于 
      During the review of seperate pquota inode patches, David noticed
that the test to detect all quotas being turned off was
incorrect, and hence the block was not freeing all the quota
information.

The check made sense in Irix, but in Linux, quota is turned off
one at a time, which makes the test invalid for Linux.

This problem existed since XFS was ported to Linux.

David suggested to fix the problem by detecting when all quotas are
turned off by checking m_qflags.
Signed-off-by: NChandra Seetharaman <sekharan@us.ibm.com>
Reviewed-by: NBen Myers <bpm@sgi.com>
Signed-off-by: NBen Myers <bpm@sgi.com>
      c31ad439
  9. 11 7月, 2013 13 次提交
  11. 10 7月, 2013 12 次提交
    • C
      xfs: fix sgid inheritance for subdirectories inheriting default acls [V3] · 42c49d7f
      由 Carlos Maiolino 提交于 
      XFS removes sgid bits of subdirectories under a directory containing a default
acl.

When a default acl is set, it implies xfs to call xfs_setattr_nonsize() in its
code path. Such function is shared among mkdir and chmod system calls, and
does some checks unneeded by mkdir (calling inode_change_ok()). Such checks
remove sgid bit from the inode after it has been granted.

With this patch, we extend the meaning of XFS_ATTR_NOACL flag to avoid these
checks when acls are being inherited (thanks hch).

Also, xfs_setattr_mode, doesn't need to re-check for group id and capabilities
permissions, this only implies in another try to remove sgid bit from the
directories. Such check is already done either on inode_change_ok() or
xfs_setattr_nonsize().

Changelog:

V2: Extends the meaning of XFS_ATTR_NOACL instead of wrap the tests into another
    function

V3: Remove S_ISDIR check in xfs_setattr_nonsize() from the patch
Signed-off-by: NCarlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: NBen Myers <bpm@sgi.com>
Signed-off-by: NBen Myers <bpm@sgi.com>
      42c49d7f
    • M
      Use ecryptfs_dentry_to_lower_path in a couple of places · cc18ec3c
      由 Matthew Wilcox 提交于 
      There are two places in ecryptfs that benefit from using
ecryptfs_dentry_to_lower_path() instead of separate calls to
ecryptfs_dentry_to_lower() and ecryptfs_dentry_to_lower_mnt().  Both
sites use fewer instructions and less stack (determined by examining
objdump output).
Signed-off-by: NMatthew Wilcox <willy@linux.intel.com>
Signed-off-by: NTyler Hicks <tyhicks@canonical.com>
      cc18ec3c
    • S
      NFS: Allow nfs_updatepage to extend a write under additional circumstances · c7559663
      由 Scott Mayhew 提交于 
      Currently nfs_updatepage allows a write to be extended to cover a full
page only if we don't have a byte range lock lock on the file... but if
we have a write delegation on the file or if we have the whole file
locked for writing then we should be allowed to extend the write as
well.
Signed-off-by: NScott Mayhew <smayhew@redhat.com>
[Trond: fix up call to nfs_have_delegation()]
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
      c7559663
    • D
      xfs: dquot log reservations are too small · b0a9dab7
      由 Dave Chinner 提交于 
      During review of the separate project quota inode patches, it became
obvious that the dquot log reservation calculation underestimated
the number dquots that can be modified in a transaction. This has
it's roots way back in the Irix quota implementation.

That is, when quotas were first implemented in XFS, it only
supported user and project quotas as Irix did not have group quotas.
Hence the worst case operation involving dquot modification was
calculated to involve 2 user dquots and 1 project dquot or 1 user
dequot and 2 project dquots. i.e. 3 dquots. This was determined back
in 1996, and has remained unchanged ever since.

However, back in 2001, the Linux XFS port dropped all support for
project quota and implmented group quotas over the top. This was
effectively done with a search-and-replace of project with group,
and as such the log reservation was not changed. However, with the
advent of group quotas, chmod and rename now could modify more than
3 dquots in a single transaction - both could modify 4 dquots. Hence
this log reservation has been wrong for a long time.

In 2005, project quota support was reintroduced into Linux, but it
was implemented to be mutually exclusive to group quotas and so this
didn't add any new changes to the dquot log reservation. Hence when
project quotas were in use (rather than group quotas) the log
reservation was again valid, just like in the Irix days.

Now, with the addition of the separate project quota inode, group
and project quotas are no longer mutually exclusive, and hence
operations can now modify three dquots per inode where previously it
was only two. The worst case here is the rename transaction, which
can allocate/free space on two different directory inodes, and if
they have different uid/gid/prid configurations and are world
writeable, then rename can actually modify 6 different dquots now.

Further, the dquot log reservation doesn't take into account the
space used by the dquot log format structure that precedes the dquot
that is logged, and hence further underestimates the worst case
log space required by dquots during a transaction. This has been
missing since the first commit in 1996.

Hence the worst case log reservation needs to be increased from 3 to
6, and it needs to take into account a log format header for each of
those dquots.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NMark Tinguely <tinguely@sgi.com>
Signed-off-by: NBen Myers <bpm@sgi.com>
      b0a9dab7
    • D
      xfs: remove local fork format handling from xfs_bmapi_write() · f3508bcd
      由 Dave Chinner 提交于 
      The conversion from local format to extent format requires
interpretation of the data in the fork being converted, so it cannot
be done in a generic way. It is up to the caller to convert the fork
format to extent format before calling into xfs_bmapi_write() so
format conversion can be done correctly.

The code in xfs_bmapi_write() to convert the format is used
implicitly by the attribute and directory code, but they
specifically zero the fork size so that the conversion does not do
any allocation or manipulation. Move this conversion into the
shortform to leaf functions for the dir/attr code so the conversions
are explicitly controlled by all callers.

Now we can remove the conversion code in xfs_bmapi_write.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NMark Tinguely <tinguely@sgi.com>
Signed-off-by: NBen Myers <bpm@sgi.com>
      f3508bcd
    • S
      NFS: Make nfs_readdir revalidate less often · 07b5ce8e
      由 Scott Mayhew 提交于 
      Make nfs_readdir revalidate only when we're at the beginning of the directory or
if the cached attributes have expired.
Signed-off-by: NScott Mayhew <smayhew@redhat.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
      07b5ce8e
    • S
      NFS: Make nfs_attribute_cache_expired() non-static · 43f291cd
      由 Scott Mayhew 提交于 
      NFS: Make nfs_attribute_cache_expired() non-static so we can call it from
nfs_readdir().
Signed-off-by: NScott Mayhew <smayhew@redhat.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
      43f291cd
    • J
      nfs: set verifier on existing dentries in nfs_prime_dcache · cda57a1e
      由 Jeff Layton 提交于 
      nfs_prime_dcache currently only sets the verifier when it doesn't
initially a matching dentry in the dcache. Set the verifier in the case
where we do find a dentry in the dcache. This ensures that we don't
have to look up the dentry again if we want to use it after a readdir.

Cc: Scott Mayhew <smayhew@redhat.com>
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
      cda57a1e
    • Y
      xfs: use get_unused_fd_flags(0) instead of get_unused_fd() · 862a6293
      由 Yann Droneaud 提交于 
      Macro get_unused_fd() is used to allocate a file descriptor with
default flags. Those default flags (0) can be "unsafe":
O_CLOEXEC must be used by default to not leak file descriptor
across exec().

Instead of macro get_unused_fd(), functions anon_inode_getfd()
or get_unused_fd_flags() should be used with flags given by userspace.
If not possible, flags should be set to O_CLOEXEC to provide userspace
with a default safe behavor.

In a further patch, get_unused_fd() will be removed so that
new code start using anon_inode_getfd() or get_unused_fd_flags()
with correct flags.

This patch replaces calls to get_unused_fd() with equivalent call to
get_unused_fd_flags(0) to preserve current behavor for existing code.

The hard coded flag value (0) should be reviewed on a per-subsystem basis,
and, if possible, set to O_CLOEXEC.
Signed-off-by: NYann Droneaud <ydroneaud@opteya.com>
Reviewed-by: NBen Myers <bpm@sgi.com>
Signed-off-by: NBen Myers <bpm@sgi.com>
      862a6293
    • J
      xfs: clean up unused codes at xfs_bulkstat() · 9cee4c5b
      由 Jie Liu 提交于 
      There are some unused codes at xfs_bulkstat():

- Variable bp is defined to point to the on-disk inode cluster
  buffer, but it proved to be of no practical help.

- We process the chunks of good inodes which were fetched by iterating
  btree records from an AG.  When processing inodes from each chunk,
  the code recomputing agbno if run into the first inode of a cluster,
  however, the agbno is not being used thereafter.

This patch tries to clean up those things.
Signed-off-by: NJie Liu <jeff.liu@oracle.com>
Reviewed-by: NDave Chinner <dchinner@redhat.com>
Signed-off-by: NBen Myers <bpm@sgi.com>
      9cee4c5b
    • E
      net/fs: change busy poll time accounting · 76b1e9b9
      由 Eliezer Tamir 提交于 
      Suggested by Linus:
Changed time accounting for busy-poll:
- Make it microsecond based.
- Use unsigned longs.
- Revert back to use time_after instead of time_in_range.
Reorder poll/select busy loop conditions:
- Clear busy_flag after one time we can't busy-poll.
- Only init busy_end if we actually are going to busy-poll.
Added one more missing need_resched() test.
Signed-off-by: NEliezer Tamir <eliezer.tamir@linux.intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      76b1e9b9
    • E
      xfs: use XFS_BMAP_BMDR_SPACE vs. XFS_BROOT_SIZE_ADJ · a69c7c07
      由 Eric Sandeen 提交于 
      XFS_BROOT_SIZE_ADJ is an undocumented macro which accounts for
the difference in size between the on-disk and in-core btree
root.  It's much clearer to just use the newly-added
XFS_BMAP_BMDR_SPACE macro which gives us the on-disk size
directly.

In one case, we must test that the if_broot exists before
applying the macro, however.
Signed-off-by: NEric Sandeen <sandeen@redhat.com>
Reviewed-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NBen Myers <bpm@sgi.com>
Signed-off-by: NBen Myers <bpm@sgi.com>
      a69c7c07