Commit Graph

281 Commits

Author SHA1 Message Date
Linus Torvalds
b403f23044 We've got ten patches this time, half of which are related to a plethora
of nasty outcomes when inodes are transitioned from the unlinked state
 to the free state. Small file systems are particularly vulnerable to these
 problems, and it can manifest as mainly hangs, but also file system
 corruption. The patches have been tested for literally many weeks, with a
 very gruelling test, so I have a high level of confidence.
 
 - Andreas Gruenbacher wrote a series of 5 patches for various lockups
   during the transition of inodes from unlinked to free. The main patch
   is titled "Fix gfs2_lookup_by_inum lock inversion" and the other 4 are
   support and cleanup patches related to that.
 - Ben Marzinski contributed 2 patches with regard to a recreatable
   problem when gfs2 tries to write a page to a file that is being
   truncated, resulting in a BUG() in gfs2_remove_from_journal.
   Note that Ben had to export vfs function __block_write_full_page to get
   this to work properly. It's been posted a long time and he talked to
   various VFS people about it, and nobody seemed to mind.
 - I contributed 3 patches. (1) The first one fixes a memory corruptor:
   a race in which one process can overwrite the gl_object pointer set by
   another process, causing kernel panic and other symptoms. (2) The second
   patch fixes another race that resulted in a false-positive BUG_ON. This
   occurred when resource group reservations were freed by one process
   while another process was trying to grab a new reservation in the same
   resource group. (3) The third patch fixes a problem with doing journal
   replay when the journals are not all the same size.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQEcBAABAgAGBQJXklXIAAoJENeLYdPf93o7AbIIAImLEixK+4CaItEArAKG9TXv
 WbO+eDJfo6AOtAteB6+MdX2UxXAHJsCY6RmiEIAi5LzlVFiiCgRo4z/QgDARAw3c
 2RxlndElaESh82S27sLiFbgZeY7GZv04C0t6AzMkc830BLXiKMs6bXfeq1fzW8Sf
 AgAneACVsX0faRWo/XDuQcK81dwZ+qdOnR2+FvtOSFl1KgV0BrtnsW7IHv+5MIot
 SREDN7VvSQwQrLgwMlC0PvhwK3KCVvuO9ZziLEPpYJONESJfEmuCpG265+tUJNTw
 dIcW3p/vvgow8fb56fSnAxaeplPLlF9qJCq1M9fWZrKVbHg2uyCZMx4P52Fnmz4=
 =uUVs
 -----END PGP SIGNATURE-----

Merge tag 'gfs2-4.7.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2

Pull gfs2 updates from Bob Peterson:
 "We've got ten patches this time, half of which are related to a
  plethora of nasty outcomes when inodes are transitioned from the
  unlinked state to the free state.  Small file systems are particularly
  vulnerable to these problems, and it can manifest as mainly hangs, but
  also file system corruption.  The patches have been tested for
  literally many weeks, with a very gruelling test, so I have a high
  level of confidence.

   - Andreas Gruenbacher wrote a series of five patches for various
     lockups during the transition of inodes from unlinked to free.

     The main patch is titled "Fix gfs2_lookup_by_inum lock inversion"
     and the other four are support and cleanup patches related to that.

   - Ben Marzinski contributed two patches with regard to a recreatable
     problem when gfs2 tries to write a page to a file that is being
     truncated, resulting in a BUG() in gfs2_remove_from_journal.

     Note that Ben had to export vfs function __block_write_full_page to
     get this to work properly.  It's been posted a long time and he
     talked to various VFS people about it, and nobody seemed to mind.

   - I contributed 3 patches:
       o The first one fixes a memory corruptor: a race in which one
         process can overwrite the gl_object pointer set by another
         process, causing kernel panic and other symptoms.
       o The second patch fixes another race that resulted in a
         false-positive BUG_ON.  This occurred when resource group
         reservations were freed by one process while another process
         was trying to grab a new reservation in the same resource
         group.
       o The third patch fixes a problem with doing journal replay when
         the journals are not all the same size"

* tag 'gfs2-4.7.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2:
  GFS2: Fix gfs2_replay_incr_blk for multiple journal sizes
  GFS2: Check rs_free with rd_rsspin protection
  gfs2: writeout truncated pages
  fs: export __block_write_full_page
  gfs2: Lock holder cleanup
  gfs2: Large-filesystem fix for 32-bit systems
  gfs2: Get rid of gfs2_ilookup
  gfs2: Fix gfs2_lookup_by_inum lock inversion
  gfs2: Initialize iopen glock holder for new inodes
  GFS2: don't set rgrp gl_object until it's inserted into rgrp tree
2016-07-24 16:07:52 -07:00
Al Viro
00699ad857 Use the right predicate in ->atomic_open() instances
->atomic_open() can be given an in-lookup dentry *or* a negative one
found in dcache.  Use d_in_lookup() to tell one from another, rather
than d_unhashed().

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-07-05 16:02:23 -04:00
Andreas Gruenbacher
6df9f9a253 gfs2: Lock holder cleanup
Make the code more readable by cleaning up the different ways of
initializing lock holders and checking for initialized lock holders:
mark lock holders as uninitialized by setting the holder's glock to NULL
(gfs2_holder_mark_uninitialized) instead of zeroing out the entire
object or using a separate flag.  Recognize initialized holders by their
non-NULL glock (gfs2_holder_initialized).  Don't zero out holder objects
which are immeditiately initialized via gfs2_holder_init or
gfs2_glock_nq_init.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2016-06-27 09:47:09 -05:00
Andreas Gruenbacher
cda9dd4207 gfs2: Large-filesystem fix for 32-bit systems
Commit ff34245d switched from iget5_locked to iget_locked among other
things, but iget_locked doesn't work for filesystems larger than 2^32
blocks on 32-bit systems.  Switch back to iget5_locked.  Filesystems
larger than 2^32 blocks are unrealistic to work well on 32-bit systems,
so this is mostly a code cleanliness fix.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2016-06-27 09:47:08 -05:00
Andreas Gruenbacher
ec5ec66ba4 gfs2: Get rid of gfs2_ilookup
Now that gfs2_lookup_by_inum only takes the inode glock for new inodes
(and not for cached inodes anymore), there no longer is a need to
optimize the cached-inode case in gfs2_get_dentry or delete_work_func,
and gfs2_ilookup can be removed.

In addition, gfs2_get_dentry wasn't checking the GFS2_DIF_SYSTEM flag in
i_diskflags in the gfs2_ilookup case (see gfs2_lookup_by_inum); this
inconsistency goes away as well.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2016-06-27 09:47:08 -05:00
Andreas Gruenbacher
3ce37b2cb4 gfs2: Fix gfs2_lookup_by_inum lock inversion
The current gfs2_lookup_by_inum takes the glock of a presumed inode
identified by block number, verifies that the block is indeed an inode,
and then instantiates and reads the new inode via gfs2_inode_lookup.

However, instantiating a new inode may block on freeing a previous
instance of that inode (__wait_on_freeing_inode), and freeing an inode
requires to take the glock already held, leading to lock inversion and
deadlock.

Fix this by first instantiating the new inode, then verifying that the
block is an inode (if required), and then reading in the new inode, all
in gfs2_inode_lookup.

If the block we are looking for is not an inode, we discard the new
inode via iget_failed, which marks inodes as bad and unhashes them.
Other tasks waiting on that inode will get back a bad inode back from
ilookup or iget_locked; in that case, retry the lookup.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2016-06-27 09:47:07 -05:00
Linus Torvalds
be1332c099 We've got nine patches this time:
- Abhi Das has two patches that fix a GFS2 splice issue (and an adjustment).
 - Ben Marzinski has a patch which allows the proper unmount of a GFS2
   file system after hitting a withdraw error.
 - I have a patch to fix a problem where GFS2 would dereference an error
   value, plus three cosmetic / refactoring patches.
 - Daniel DeFreez has a patch to fix two glock reference count problems,
   where GFS2 was not properly "uninitializing" its glock holder on error
   paths.
 - Denys Vlasenko has a patch to change a function to not be inlined,
   thus reducing the memory footprint of the GFS2 module.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQEcBAABAgAGBQJXP2KLAAoJENeLYdPf93o7nScH/jlDCv+JzwBwAiFEVelgB657
 lFY+Q3bPvmcTaHiOqXzco7U1EeyvAuZ+x9duaFBBEGC2/NydIbkAdCP1XjDOTAGZ
 aVVAP8qov4adFiXTfBdzMYjJ7DArOy/JRnlC8WK5OiD/3yxsXJZNlAHTgjjL/ZMq
 PkhjxX2Lc9ZHGF9YIFTyeoBlqf1qO6WbhkxvSNefgq3c702QPM+T9XND5T1duGDF
 ThEcXS2DRRoE+6wr3h+ruvS5kcfxXRLLausAgqNpj2FYQOFCQ6XXgGK8pyXA5V/t
 3Vh8mHW0VmSjAfrRWslCRjd+APXoOf+7QHqOHUAA1dvQ6CGfC9qTETH9Wp32JCI=
 =8g+a
 -----END PGP SIGNATURE-----

Merge tag 'gfs2-4.7.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2

Pull GFS2 updates from Bob Peterson:
 "We've got nine patches this time:

   - Abhi Das has two patches that fix a GFS2 splice issue (and an
     adjustment).

   - Ben Marzinski has a patch which allows the proper unmount of a GFS2
     file system after hitting a withdraw error.

   - I have a patch to fix a problem where GFS2 would dereference an
     error value, plus three cosmetic / refactoring patches.

   - Daniel DeFreez has a patch to fix two glock reference count
     problems, where GFS2 was not properly "uninitializing" its glock
     holder on error paths.

   - Denys Vlasenko has a patch to change a function to not be inlined,
     thus reducing the memory footprint of the GFS2 module"

* tag 'gfs2-4.7.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2:
  GFS2: Refactor gfs2_remove_from_journal
  GFS2: Remove allocation parms from gfs2_rbm_find
  gfs2: use inode_lock/unlock instead of accessing i_mutex directly
  GFS2: Add calls to gfs2_holder_uninit in two error handlers
  GFS2: Don't dereference inode in gfs2_inode_lookup until it's valid
  GFS2: fs/gfs2/glock.c: Deinline do_error, save 1856 bytes
  gfs2: Use gfs2 wrapper to sync inode before calling generic_file_splice_read()
  GFS2: Get rid of dead code in inode_go_demote_ok
  GFS2: ignore unlock failures after withdraw
2016-05-20 15:11:26 -07:00
Al Viro
1a39ba99b5 gfs2: Switch to generic xattr handlers
Switch to the generic xattr handlers and take the necessary glocks at
the layer below. The following are the new xattr "entry points"; they
are called with the glock held already in the following cases:

  gfs2_xattr_get: From SELinux, during lookups.
  gfs2_xattr_set: The glock is never held.
  gfs2_get_acl: From gfs2_create_inode -> posix_acl_create and
                gfs2_setattr -> posix_acl_chmod.
  gfs2_set_acl: From gfs2_setattr -> posix_acl_chmod.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-05-12 22:28:05 -04:00
Bob Peterson
e97321fa09 GFS2: Don't dereference inode in gfs2_inode_lookup until it's valid
Function gfs2_inode_lookup was dereferencing the inode, and after,
it checks for the value being NULL. We need to check that first.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2016-04-14 09:52:50 -04:00
Al Viro
ce23e64013 ->getxattr(): pass dentry and inode as separate arguments
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-04-11 00:48:00 -04:00
Linus Torvalds
1ca80a0a3e GFS2: merge window
We only have six patches ready for this merge window.
 
 - Arnd Bergmann contributed a patch that fixes an uninitialized variable
   warning.
 - The second patch avoids a kernel panic due to referencing an iopen
   glock that may not be held, in an error path.
 - The third patch fixes a rounding error that caused xfs_tests direct IO
   write "fsx" tests to fail on GFS2.
 - The fourth patch tidies up the code path when glocks are being reused
   to recreate a dinode that was recently deleted.
 - The fifth reverts an ages-old patch that should no longer be needed, and
   which interfered with the transition of dinodes from unlinked to free.
 - And lastly, a patch to eliminate a function parameter that's not needed.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQEcBAABAgAGBQJW6qcKAAoJENeLYdPf93o70SwH/0czrFBIWaPbRgyuGLNvye4G
 qvfIk2Yky3UKfgUA+ZW+cAWkxeKubc9scMwce0elKxm0e03rNwIX0slIOx8hymj3
 19AgMnj3kcCJvRLdkBITNqnd6vTY2quadLN3j8I2cCNbHOV0GelEkP4jWcTHB+2F
 AG0ZJOsvvrcD1ClgdIvGdV52qipZApS/kgZjLpJBEyzxq8SpRe9vNqMDsDyoKWgi
 yjp0+aJ0IJAWA24fzdT5HE4fb5yGRWehg51l6Z2mbfXAvT+oeKcYrQiq1zhUutHw
 dT6SUHbjt+y0EulPClsf3r5zjRjVCCbpj0wkUY3kPB98lgnpAD2QnUP/JDA+CD0=
 =xRmX
 -----END PGP SIGNATURE-----

Merge tag 'gfs2-merge-window' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2

Pull GFS2 updates from Bob Peterson:
 "We only have six patches ready for this merge window:

   - Arnd Bergmann contributed a patch that fixes an uninitialized
     variable warning.

   - The second patch avoids a kernel panic due to referencing an iopen
     glock that may not be held, in an error path.

   - The third patch fixes a rounding error that caused xfs_tests direct
     IO write "fsx" tests to fail on GFS2.

   - The fourth patch tidies up the code path when glocks are being
     reused to recreate a dinode that was recently deleted.

   - The fifth reverts an ages-old patch that should no longer be
     needed, and which interfered with the transition of dinodes from
     unlinked to free.

   - And lastly, a patch to eliminate a function parameter that's not
     needed"

* tag 'gfs2-merge-window' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2:
  GFS2: Eliminate parameter non_block on gfs2_inode_lookup
  GFS2: Don't filter out I_FREEING inodes anymore
  GFS2: Prevent delete work from occurring on glocks used for create
  GFS2: Fix direct IO write rounding error
  gfs2: avoid uninitialized variable warning
  GFS2: Check if iopen is held when deleting inode
2016-03-17 16:51:32 -07:00
Bob Peterson
73b462d280 GFS2: Eliminate parameter non_block on gfs2_inode_lookup
Now that we're not filtering out I_FREEING inodes from our lookups
anymore, we can eliminate the non_block parameter from the lookup
function.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Acked-by: Steven Whitehouse <swhiteho@redhat.com>
2016-03-15 10:46:50 -04:00
Bob Peterson
ff34245d52 GFS2: Don't filter out I_FREEING inodes anymore
This patch basically reverts a very old patch from 2008,
7a9f53b3c1, with the title
"Alternate gfs2_iget to avoid looking up inodes being freed".
The original patch was designed to avoid a deadlock caused by lock
ordering with try_rgrp_unlink. The patch forced the function to not
find inodes that were being removed by VFS. The problem is, that
made it impossible for nodes to delete their own unlinked dinodes
after a certain point in time, because the inode needed was not found
by this filtering process. There is no longer a need for the patch,
since function try_rgrp_unlink no longer locks the inode: All it does
is queue the glock onto the delete work_queue, so there should be no
more deadlock.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2016-03-15 10:46:45 -04:00
Bob Peterson
a4923865ea GFS2: Prevent delete work from occurring on glocks used for create
This patch tries to prevent delete work (queued via iopen callback)
from executing if the glock is currently being used to create
a new inode.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Acked-by: Steven Whitehouse <swhiteho@redhat.com>
2016-03-15 10:46:37 -04:00
Al Viro
5955102c99 wrappers for ->i_mutex access
parallel to mutex_{lock,unlock,trylock,is_locked,lock_nested},
inode_foo(inode) being mutex_foo(&inode->i_mutex).

Please, use those for access to ->i_mutex; over the coming cycle
->i_mutex will become rwsem, with ->lookup() done with it held
only shared.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-01-22 18:04:28 -05:00
Linus Torvalds
4d58967783 GFS2: merge window
Here is a list of patches we've accumulated for GFS2 for the current upstream
 merge window. Last window's set was short, but I warned that this one would
 be bigger, and so it is. We've got 19 patches:
 
 - A patch from Abhi Das to propagate the GFS2_DIF_SYSTEM bit so that newly
   added journals don't get flagged, deleted, and recreated by fsck.gfs2.
 - Two patches from Andreas Gruenbacher to improve GFS2 performance where
   extended attributes are involved.
 - A patch from Andy Price to fix a suspicious rcu dereference error.
 - Two patches from Ben Marzinski that rework how GFS2's NFS cookies are
   managed. This fixes readdir problems with nfs-over-gfs2.
 - A patch from Ben Marzinski that fixes a race in unmounting GFS2.
 - A set of four patches from me to move the resource group reservations
   inside the gfs2 inode to improve performance and fix a bug whereby
   get_write_access improperly prevented some operations like chown.
 - A patch from me to spinlock-protect the setting of system statfs file data.
   This was causing small discrepancies between df and du.
 - A patch from me to reintroduce a timeout while clearing glocks which was
   accidentally dropped some time ago.
 - A patch from me to wait for iopen glock dequeues in order to improve
   deleting of files that were unlinked from a different cluster node.
 - A patch from me to ensure metadata address spaces get truncated when an
   inode is evicted.
 - A patch from me to fix a bug in which a memory leak could occur in some
   error cases when inodes were trying to be created.
 - A patch to consistently use iopen glocks to transition from the unlinked
   state to the deleted state.
 - A patch to fix a glock reference count error when inode creation fails.
 - A patch from Junxiao Bi to fix an flock panic.
 - A patch from Markus Elfring that removes an unnecessary if.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQEcBAABAgAGBQJWlUOCAAoJENeLYdPf93o78/IH/0PfoQtQnYQpvbTPgaFICEUI
 rx+uLqPxpJgjJMsbIy+VA/bhZsbuENDbor99Cs6GiTLy3Q/4TKNY9NxDN+aO8o+Q
 qrp3ZANkyTGaneCzrXzfgmOxe1G8xRQ7pboRUEt2yPlGK1oLax+PR4uPb+IuJ5Wa
 QvSwnZj+9K2LkMQkKPyxoltjZiZLywvNB5dx0F35+dvriQxHXfJ1Naek6gs140MB
 SfG4/Zi8dfGOJQjSQTUENatFhyFB0V7CbDPFuBVzTGD8IS4ASgqIBMFjO0VBHkP4
 gt4zb0BJAn0aQcbxIaDtsuEffpn+5zdK/Onq5g4Fr9ZJv3fkVpVcOgYui/rkDD0=
 =28ev
 -----END PGP SIGNATURE-----

Merge tag 'gfs2-merge-window' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2

Pull GFS2 updates from Bob Peterson:
 "Here is a list of patches we've accumulated for GFS2 for the current
  upstream merge window.  Last window's set was short, but I warned that
  this one would be bigger, and so it is.  We've got 19 patches:

   - A patch from Abhi Das to propagate the GFS2_DIF_SYSTEM bit so that
     newly added journals don't get flagged, deleted, and recreated by
     fsck.gfs2.

   - Two patches from Andreas Gruenbacher to improve GFS2 performance
     where extended attributes are involved.

   - A patch from Andy Price to fix a suspicious rcu dereference error.

   - Two patches from Ben Marzinski that rework how GFS2's NFS cookies
     are managed.  This fixes readdir problems with nfs-over-gfs2.

   - A patch from Ben Marzinski that fixes a race in unmounting GFS2.

   - A set of four patches from me to move the resource group
     reservations inside the gfs2 inode to improve performance and fix a
     bug whereby get_write_access improperly prevented some operations
     like chown.

   - A patch from me to spinlock-protect the setting of system statfs
     file data.  This was causing small discrepancies between df and du.

   - A patch from me to reintroduce a timeout while clearing glocks
     which was accidentally dropped some time ago.

   - A patch from me to wait for iopen glock dequeues in order to
     improve deleting of files that were unlinked from a different
     cluster node.

   - A patch from me to ensure metadata address spaces get truncated
     when an inode is evicted.

   - A patch from me to fix a bug in which a memory leak could occur in
     some error cases when inodes were trying to be created.

   - A patch to consistently use iopen glocks to transition from the
     unlinked state to the deleted state.

   - A patch to fix a glock reference count error when inode creation
     fails.

   - A patch from Junxiao Bi to fix an flock panic.

   - A patch from Markus Elfring that removes an unnecessary if"

* tag 'gfs2-merge-window' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2:
  gfs2: fix flock panic issue
  GFS2: Don't do glock put on when inode creation fails
  GFS2: Always use iopen glock for gl_deletes
  GFS2: Release iopen glock in gfs2_create_inode error cases
  GFS2: Truncate address space mapping when deleting an inode
  GFS2: Wait for iopen glock dequeues
  gfs2: clear journal live bit in	gfs2_log_flush
  gfs2: change gfs2 readdir cookie
  gfs2: keep offset when splitting dir leaf blocks
  GFS2: Reintroduce a timeout in function gfs2_gl_hash_clear
  GFS2: Update master statfs buffer with sd_statfs_spin locked
  GFS2: Reduce size of incore inode
  GFS2: Make rgrp reservations part of the gfs2_inode structure
  GFS2: Extract quota data from reservations structure (revert 5407e24)
  gfs2: Extended attribute readahead optimization
  gfs2: Extended attribute readahead
  GFS2: Use rht_for_each_entry_rcu in glock_hash_walk
  GFS2: Delete an unnecessary check before the function call "iput"
  gfs2: Automatically set GFS2_DIF_SYSTEM flag on system files
2016-01-12 18:09:35 -08:00
Al Viro
fceef393a5 switch ->get_link() to delayed_call, kill ->put_link()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-12-30 13:01:03 -05:00
Bob Peterson
6cc4b6e801 GFS2: Don't do glock put on when inode creation fails
Currently the error path of function gfs2_inode_lookup calls function
gfs2_glock_put corresponding to an earlier call to gfs2_glock_get for
the inode glock. That's wrong because the error path also calls
iget_failed() which eventually calls iput, which eventually calls
gfs2_evict_inode, which does another gfs2_glock_put. This double-put
can cause the glock reference count to get off.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2015-12-18 11:04:46 -06:00
Bob Peterson
783013c0f5 GFS2: Release iopen glock in gfs2_create_inode error cases
Some error cases in gfs2_create_inode were not unlocking the iopen
glock, getting the reference count off. This adds the proper unlock.
The error logic in function gfs2_create_inode was also convoluted,
so this patch simplifies it. It also takes care of a bug in
which gfs2_qa_delete() was not called in an error case.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2015-12-18 10:57:21 -06:00
Bob Peterson
86d067a797 GFS2: Wait for iopen glock dequeues
This patch changes every glock_dq for iopen glocks into a dq_wait.
This makes sure that iopen glocks do not outlive the inode itself.
In turn, that ensures that anyone trying to unlink the glock will
be able to find the inode when it receives a remote iopen callback.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Acked-by: Steven Whitehouse <swhiteho@redhat.com>
2015-12-18 10:49:22 -06:00
Bob Peterson
a097dc7e24 GFS2: Make rgrp reservations part of the gfs2_inode structure
Before this patch, multi-block reservation structures were allocated
from a special slab. This patch folds the structure into the gfs2_inode
structure. The disadvantage is that the gfs2_inode needs more memory,
even when a file is opened read-only. The advantages are: (a) we don't
need the special slab and the extra time it takes to allocate and
deallocate from it. (b) we no longer need to worry that the structure
exists for things like quota management. (c) This also allows us to
remove the calls to get_write_access and put_write_access since we
know the structure will exist.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2015-12-14 12:16:38 -06:00
Al Viro
6b2553918d replace ->follow_link() with new method that could stay in RCU mode
new method: ->get_link(); replacement of ->follow_link().  The differences
are:
	* inode and dentry are passed separately
	* might be called both in RCU and non-RCU mode;
the former is indicated by passing it a NULL dentry.
	* when called that way it isn't allowed to block
and should return ERR_PTR(-ECHILD) if it needs to be called
in non-RCU mode.

It's a flagday change - the old method is gone, all in-tree instances
converted.  Conversion isn't hard; said that, so far very few instances
do not immediately bail out when called in RCU mode.  That'll change
in the next commits.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-12-08 22:41:54 -05:00
Bob Peterson
b54e9a0b92 GFS2: Extract quota data from reservations structure (revert 5407e24)
This patch basically reverts the majority of patch 5407e24.
That patch eliminated the gfs2_qadata structure in favor of just
using the reservations structure. The problem with doing that is that
it increases the size of the reservations structure. That is not an
issue until it comes time to fold the reservations structure into the
inode in memory so we know it's always there. By separating out the
quota structure again, we aren't punishing the non-quota users by
making all the inodes bigger, requiring more slab space. This patch
creates a new slab area to allocate the quota stuff so it's managed
a little more sanely.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2015-11-24 08:38:44 -06:00
Abhi Das
acc546fd61 gfs2: Automatically set GFS2_DIF_SYSTEM flag on system files
When new files and directories are created inside a parent directory
we automatically inherit the GFS2_DIF_SYSTEM flag (if set) and assign
it to the new file/dirs.

All new system files/dirs created in the metafs by, say gfs2_jadd,
will have this flag set because they will have parent directories in
the metafs whose GFS2_DIF_SYSTEM flag has already been set (most likely
by a previous mkfs.gfs2)

Signed-off-by: Abhi Das <adas@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2015-11-10 15:11:06 -06:00
Linus Torvalds
546fac6073 GFS2: merge window
Here is a list of patches we've accumulated for GFS2 for the current upstream
 merge window. We have a good mixture this time. Here are some of the features:
 
 1. Fix a problem with RO mounts writing to the journal.
 2. Further improvements to quotas on GFS2.
 3. Added support for rename2 and RENAME_EXCHANGE on GFS2.
 4. Increase performance by making glock lru_list less of a bottleneck.
 5. Increase performance by avoiding unnecessary buffer_head releases.
 6. Increase performance by using average glock round trip time from all CPUs.
 7. Fixes for some compiler warnings and minor white space issues.
 8. Other misc. bug fixes
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQEbBAABAgAGBQJVjFEXAAoJENeLYdPf93o7zqoH926XV0oddQCsGCYg6gq7OL+c
 /4q2y9x31hkv5XbPTNcahqR6UsK8JcbcdZD+XAqTftL4Q789FDAdWbYS++45qz8D
 YuUFgZd2bc75Ge2qqacgEdv85YRLtws1fRnI6DUpjfN1qJ9kJXX+gk+BSve6rh6V
 Qyv8a4DRIw1En5fwt0R6yIg0LI/ywPhYeVlxo6WUoK8fiL/i3eNd57Jgv5YQ6ly+
 ZyqH8w1m0kE4IkIiTFgmIpvepiWLBCA3mPOfHfE3QxbDKpXe4uFsMdnxghmP5bFN
 3H9syJQNFqjs+ooKma/fE2VmpxQ5/5lAs0/ms+ECW3GvBseTll8Iln7y4NwgAQ==
 =ITwD
 -----END PGP SIGNATURE-----

Merge tag 'gfs2-merge-window' of git://git.kernel.org:/pub/scm/linux/kernel/git/gfs2/linux-gfs2

Pull GFS2 updates from Bob Peterson:
 "Here are the patches we've accumulated for GFS2 for the current
  upstream merge window.  We have a good mixture this time.  Here are
  some of the features:

   - Fix a problem with RO mounts writing to the journal.

   - Further improvements to quotas on GFS2.

   - Added support for rename2 and RENAME_EXCHANGE on GFS2.

   - Increase performance by making glock lru_list less of a bottleneck.

   - Increase performance by avoiding unnecessary buffer_head releases.

   - Increase performance by using average glock round trip time from all CPUs.

   - Fixes for some compiler warnings and minor white space issues.

   - Other misc bug fixes"

* tag 'gfs2-merge-window' of git://git.kernel.org:/pub/scm/linux/kernel/git/gfs2/linux-gfs2:
  GFS2: Don't brelse rgrp buffer_heads every allocation
  GFS2: Don't add all glocks to the lru
  gfs2: Don't support fallocate on jdata	files
  gfs2: s64 cast for negative quota value
  gfs2: limit quota log messages
  gfs2: fix quota updates on block boundaries
  gfs2: fix shadow warning in gfs2_rbm_find()
  gfs2: kerneldoc warning fixes
  gfs2: convert simple_str to kstr
  GFS2: make sure S_NOSEC flag isn't overwritten
  GFS2: add support for rename2 and RENAME_EXCHANGE
  gfs2: handle NULL rgd in set_rgrp_preferences
  GFS2: inode.c: indent with TABs, not spaces
  GFS2: mark the journal idle to fix ro mounts
  GFS2: Average in only non-zero round-trip times for congestion stats
  GFS2: Use average srttb value in congestion calculations
2015-06-27 09:47:46 -07:00
Abhi Das
39a725803b gfs2: fix quota updates on block boundaries
For smaller block sizes (512B, 1K, 2K), some quotas straddle block
boundaries such that the usage value is on one block and the rest
of the quota is on the previous block. In such cases, the value
does not get updated correctly. This patch fixes that by addressing
the boundary conditions correctly.

This patch also adds a (s64) cast that was missing in a call to
gfs2_quota_change() in inode.c

Signed-off-by: Abhi Das <adas@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2015-06-02 11:02:24 -05:00
Al Viro
6e77137b36 don't pass nameidata to ->follow_link()
its only use is getting passed to nd_jump_link(), which can obtain
it from current->nameidata

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-05-10 22:20:15 -04:00
Al Viro
680baacbca new ->follow_link() and ->put_link() calling conventions
a) instead of storing the symlink body (via nd_set_link()) and returning
an opaque pointer later passed to ->put_link(), ->follow_link() _stores_
that opaque pointer (into void * passed by address by caller) and returns
the symlink body.  Returning ERR_PTR() on error, NULL on jump (procfs magic
symlinks) and pointer to symlink body for normal symlinks.  Stored pointer
is ignored in all cases except the last one.

Storing NULL for opaque pointer (or not storing it at all) means no call
of ->put_link().

b) the body used to be passed to ->put_link() implicitly (via nameidata).
Now only the opaque pointer is.  In the cases when we used the symlink body
to free stuff, ->follow_link() now should store it as opaque pointer in addition
to returning it.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-05-10 22:19:45 -04:00
Benjamin Marzinski
a63b7bbc21 GFS2: add support for rename2 and RENAME_EXCHANGE
gfs2 now uses the rename2 directory iop, and supports the
RENAME_EXCHANGE flag (as well as RENAME_NOREPLACE, which the vfs
takes care of).

Signed-off-by: Benjamin Marzinski <bmarzins redhat com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2015-05-05 12:12:19 -05:00
Antonio Ospite
86fbca4923 GFS2: inode.c: indent with TABs, not spaces
Follow the same style used for the other functions in the same file.

Signed-off-by: Antonio Ospite <ao2@ao2.it>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2015-05-01 12:54:38 -05:00
Linus Torvalds
9ec3a646fe Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull fourth vfs update from Al Viro:
 "d_inode() annotations from David Howells (sat in for-next since before
  the beginning of merge window) + four assorted fixes"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  RCU pathwalk breakage when running into a symlink overmounting something
  fix I_DIO_WAKEUP definition
  direct-io: only inc/dec inode->i_dio_count for file systems
  fs/9p: fix readdir()
  VFS: assorted d_backing_inode() annotations
  VFS: fs/inode.c helpers: d_inode() annotations
  VFS: fs/cachefiles: d_backing_inode() annotations
  VFS: fs library helpers: d_inode() annotations
  VFS: assorted weird filesystems: d_inode() annotations
  VFS: normal filesystems (and lustre): d_inode() annotations
  VFS: security/: d_inode() annotations
  VFS: security/: d_backing_inode() annotations
  VFS: net/: d_inode() annotations
  VFS: net/unix: d_backing_inode() annotations
  VFS: kernel/: d_inode() annotations
  VFS: audit: d_backing_inode() annotations
  VFS: Fix up some ->d_inode accesses in the chelsio driver
  VFS: Cachefiles should perform fs modifications on the top layer only
  VFS: AF_UNIX sockets should call mknod on the top layer only
2015-04-26 17:22:07 -07:00
David Howells
2b0143b5c9 VFS: normal filesystems (and lustre): d_inode() annotations
that's the bulk of filesystem drivers dealing with inodes of their own

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-15 15:06:57 -04:00
Abhi Das
b8fbf471ed gfs2: perform quota checks against allocation parameters
Use struct gfs2_alloc_parms as an argument to gfs2_quota_check()
and gfs2_quota_lock_check() to check for quota violations while
accounting for the new blocks requested by the current operation
in ap->target.

Previously, the number of new blocks requested during an operation
were not accounted for during quota_check and would allow these
operations to exceed quota. This was not very apparent since most
operations allocated only 1 block at a time and quotas would get
violated in the next operation. i.e. quota excess would only be by
1 block or so. With fallocate, (where we allocate a bunch of blocks
at once) the quota excess is non-trivial and is addressed by this
patch.

Signed-off-by: Abhi Das <adas@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Acked-by: Steven Whitehouse <swhiteho@redhat.com>
2015-03-18 12:46:54 -05:00
Bob Peterson
45094a58b1 GFS2: Eliminate a nonsense goto
This patch just removes a goto that did nothing.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2015-01-26 20:58:54 +00:00
Al Viro
ec7d879c45 GFS2: gfs2_atomic_open(): simplify the use of finish_no_open()
In ->atomic_open(inode, dentry, file, opened) calling finish_no_open(file, NULL)
is equivalent to dget(dentry); return finish_no_open(file, dentry);

No need to open-code that...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2014-11-20 11:18:08 +00:00
Al Viro
44bb31bac5 GFS2: gfs2_create_inode(): don't bother with d_splice_alias()
dentry is always hashed and negative, inode - non-error, non-NULL and
non-directory.  In such conditions d_splice_alias() is equivalent to
"d_instantiate(dentry, inode) and return NULL", which simplifies the
downstream code and is consistent with the "have to create a new object"
case.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2014-11-20 10:17:39 +00:00
Al Viro
571a4b5797 GFS2: bugger off early if O_CREAT open finds a directory
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2014-11-20 10:16:58 +00:00
Benjamin Marzinski
2e60d7683c GFS2: update freeze code to use freeze/thaw_super on all nodes
The current gfs2 freezing code is considerably more complicated than it
should be because it doesn't use the vfs freezing code on any node except
the one that begins the freeze.  This is because it needs to acquire a
cluster glock before calling the vfs code to prevent a deadlock, and
without the new freeze_super and thaw_super hooks, that was impossible. To
deal with the issue, gfs2 had to do some hacky locking tricks to make sure
that a frozen node couldn't be holding on a lock it needed to do the
unfreeze ioctl.

This patch makes use of the new hooks to simply the gfs2 locking code. Now,
all the nodes in the cluster freeze and thaw in exactly the same way. Every
node in the cluster caches the freeze glock in the shared state.  The new
freeze_super hook allows the freezing node to grab this freeze glock in
the exclusive state without first calling the vfs freeze_super function.
All the nodes in the cluster see this lock change, and call the vfs
freeze_super function. The vfs locking code guarantees that the nodes can't
get stuck holding the glocks necessary to unfreeze the system.  To
unfreeze, the freezing node uses the new thaw_super hook to drop the freeze
glock. Again, all the nodes notice this, reacquire the glock in shared mode
and call the vfs thaw_super function.

Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2014-11-17 10:36:39 +00:00
Fabian Frederick
37975f1503 GFS2: directly return gfs2_dir_check()
No need to store gfs2_dir_check result and test it before returning.

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2014-11-03 19:23:32 +00:00
Linus Torvalds
77c688ac87 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs updates from Al Viro:
 "The big thing in this pile is Eric's unmount-on-rmdir series; we
  finally have everything we need for that.  The final piece of prereqs
  is delayed mntput() - now filesystem shutdown always happens on
  shallow stack.

  Other than that, we have several new primitives for iov_iter (Matt
  Wilcox, culled from his XIP-related series) pushing the conversion to
  ->read_iter()/ ->write_iter() a bit more, a bunch of fs/dcache.c
  cleanups and fixes (including the external name refcounting, which
  gives consistent behaviour of d_move() wrt procfs symlinks for long
  and short names alike) and assorted cleanups and fixes all over the
  place.

  This is just the first pile; there's a lot of stuff from various
  people that ought to go in this window.  Starting with
  unionmount/overlayfs mess...  ;-/"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (60 commits)
  fs/file_table.c: Update alloc_file() comment
  vfs: Deduplicate code shared by xattr system calls operating on paths
  reiserfs: remove pointless forward declaration of struct nameidata
  don't need that forward declaration of struct nameidata in dcache.h anymore
  take dname_external() into fs/dcache.c
  let path_init() failures treated the same way as subsequent link_path_walk()
  fix misuses of f_count() in ppp and netlink
  ncpfs: use list_for_each_entry() for d_subdirs walk
  vfs: move getname() from callers to do_mount()
  gfs2_atomic_open(): skip lookups on hashed dentry
  [infiniband] remove pointless assignments
  gadgetfs: saner API for gadgetfs_create_file()
  f_fs: saner API for ffs_sb_create_file()
  jfs: don't hash direct inode
  [s390] remove pointless assignment of ->f_op in vmlogrdr ->open()
  ecryptfs: ->f_op is never NULL
  android: ->f_op is never NULL
  nouveau: __iomem misannotations
  missing annotation in fs/file.c
  fs: namespace: suppress 'may be used uninitialized' warnings
  ...
2014-10-13 11:28:42 +02:00
Al Viro
4d93bc3e81 gfs2_atomic_open(): skip lookups on hashed dentry
hashed dentry can be passed to ->atomic_open() only if
a) it has just passed revalidation and
b) it's negative

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-10-09 02:39:15 -04:00
Bob Peterson
19aeb5a65f GFS2: Make rename not save dirent location
This patch fixes a regression in the patch "GFS2: Remember directory
insert point", commit 2b47dad866.
The problem had to do with the rename function: The function found
space for the new dirent, and remembered that location. But then the
old dirent was removed, which often moved the eligible location for
the renamed dirent. Putting the new dirent at the saved location
caused file system corruption.

This patch adds a new "save_loc" variable to struct gfs2_diradd.
If 1, the dirent location is saved. If 0, the dirent location is not
saved and the buffer_head is released as per previous behavior.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2014-10-01 14:06:15 +01:00
Abhi Das
00a158be83 GFS2: fix bad inode i_goal values during block allocation
This patch checks if i_goal is either zero or if doesn't exist
within any rgrp (i.e gfs2_blk2rgrpd() returns NULL). If so, it
assigns the ip->i_no_addr block as the i_goal.

There are two scenarios where a bad i_goal can result in a
-EBADSLT error.

1. Attempting to allocate to an existing inode:
Control reaches gfs2_inplace_reserve() and ip->i_goal is bad.
We need to fix i_goal here.

2. A new inode is created in a directory whose i_goal is hosed:
In this case, the parent dir's i_goal is copied onto the new
inode. Since the new inode is not yet created, the ip->i_no_addr
field is invalid and so, the fix in gfs2_inplace_reserve() as per
1) won't work in this scenario. We need to catch and fix it sooner
in the parent dir itself (gfs2_create_inode()), before it is
copied to the new inode.

Signed-off-by: Abhi Das <adas@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2014-09-19 10:45:18 +01:00
Al Viro
cfb2f9d5c9 GFS2: fix d_splice_alias() misuses
Callers of d_splice_alias(dentry, inode) don't need iput(), neither
on success nor on failure.  Either the reference to inode is stored
in a previously negative dentry, or it's dropped.  In either case
inode reference the caller used to hold is consumed.

__gfs2_lookup() does iput() in case when d_splice_alias() has failed.
Double iput() if we ever hit that.  And gfs2_create_inode() ends up
not only with double iput(), but with link count dropped to zero - on
an inode it has just found in directory.

Cc: stable@vger.kernel.org # v3.14+
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2014-09-12 20:58:55 +01:00
Benjamin Coddington
7b7a91152d GFS2: Hash the negative dentry during inode lookup
Fix a regression introduced by:
6d4ade986f GFS2: Add atomic_open support
where an early return misses d_splice_alias() which had been
adding the negative dentry.

Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2014-09-11 10:54:43 +01:00
Benjamin Marzinski
24972557b1 GFS2: remove transaction glock
GFS2 has a transaction glock, which must be grabbed for every
transaction, whose purpose is to deal with freezing the filesystem.
Aside from this involving a large amount of locking, it is very easy to
make the current fsfreeze code hang on unfreezing.

This patch rewrites how gfs2 handles freezing the filesystem. The
transaction glock is removed. In it's place is a freeze glock, which is
cached (but not held) in a shared state by every node in the cluster
when the filesystem is mounted. This lock only needs to be grabbed on
freezing, and actions which need to be safe from freezing, like
recovery.

When a node wants to freeze the filesystem, it grabs this glock
exclusively.  When the freeze glock state changes on the nodes (either
from shared to unlocked, or shared to exclusive), the filesystem does a
special log flush.  gfs2_log_flush() does all the work for flushing out
the and shutting down the incore log, and then it tries to grab the
freeze glock in a shared state again.  Since the filesystem is stuck in
gfs2_log_flush, no new transaction can start, and nothing can be written
to disk. Unfreezing the filesytem simply involes dropping the freeze
glock, allowing gfs2_log_flush() to grab and then release the shared
lock, so it is cached for next time.

However, in order for the unfreezing ioctl to occur, gfs2 needs to get a
shared lock on the filesystem root directory inode to check permissions.
If that glock has already been grabbed exclusively, fsfreeze will be
unable to get the shared lock and unfreeze the filesystem.

In order to allow the unfreeze, this patch makes gfs2 grab a shared lock
on the filesystem root directory during the freeze, and hold it until it
unfreezes the filesystem.  The functions which need to grab a shared
lock in order to allow the unfreeze ioctl to be issued now use the lock
grabbed by the freeze code instead.

The freeze and unfreeze code take care to make sure that this shared
lock will not be dropped while another process is using it.

Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2014-05-14 10:04:34 +01:00
Abhi Das
059788039f GFS2: Fix uninitialized VFS inode in gfs2_create_inode
When gfs2_create_inode() fails due to quota violation, the VFS
inode is not completely uninitialized. This can cause a list
corruption error.

This patch correctly uninitializes the VFS inode when a quota
violation occurs in the gfs2_create_inode codepath.

Resolves: rhbz#1059808
Signed-off-by: Abhi Das <adas@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2014-03-31 16:41:39 +01:00
Bob Peterson
f45dc26ded GFS2: Remove extraneous function gfs2_security_init
This patch eliminates function gfs2_security_init in favor of just
calling security_inode_init_security directly.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2014-03-19 15:16:58 +00:00
Abhi Das
48f8f711ed GFS2: check NULL return value in gfs2_ok_to_move
gfs2_lookupi() can return NULL if the path to the root is broken by
another rename/rmdir. In this case gfs2_ok_to_move() must check for
this NULL pointer and return error.

Resolves: rhbz#1060246
Signed-off-by: Abhi Das <adas@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2014-03-12 09:50:27 +00:00
Steven Whitehouse
b2c8b3ea87 GFS2: Allocate block for xattr at inode alloc time, if required
This is another step towards improving the allocation of xattr
blocks at inode allocation time. Here we take advantage of
Christoph's recent work on ACLs to allocate a block for the
xattrs early if we know that we will be adding ACLs to the
inode later on. The advantage of that is that it is much
more likely that we'll get a contiguous run of two blocks
where the first is the inode and the second is the xattr block.

We still have to fall back to the original system in case we
don't get the requested two contiguous blocks, or in case the
ACLs are too large to fit into the block.

Future patches will move more of the ACL setting code further
up the gfs2_inode_create() function. Also, I'd like to be
able to do the same thing with the xattrs from LSMs in
due course, too. That way we should be able to slowly reduce
the number of independent transactions, at least in the
most common cases.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2014-02-04 15:45:11 +00:00