linux.git/fs/xfs, branch v3.11

xfs: di_flushiter considered harmful

2013-07-25T15:41:42+00:00

When we made all inode updates transactional, we no longer needed
the log recovery detection for inodes being newer on disk than the
transaction being replayed - it was redundant as replay of the log
would always result in the latest version of the inode would be on
disk. It was redundant, but left in place because it wasn't
considered to be a problem.

However, with the new "don't read inodes on create" optimisation,
flushiter has come back to bite us. Essentially, the optimisation
made always initialises flushiter to zero in the create transaction,
and so if we then crash and run recovery and the inode already on
disk has a non-zero flushiter it will skip recovery of that inode.
As a result, log recovery does the wrong thing and we end up with a
corrupt filesystem.

Because we have to support old kernel to new kernel upgrades, we
can't just get rid of the flushiter support in log recovery as we
might be upgrading from a kernel that doesn't have fully transactional
inode updates.  Unfortunately, for v4 superblocks there is no way to
guarantee that log recovery knows about this fact.

We cannot add a new inode format flag to say it's a "special inode
create" because it won't be understood by older kernels and so
recovery could do the wrong thing on downgrade. We cannot specially
detect the combination of zero mode/non-zero flushiter on disk to
non-zero mode, zero flushiter in the log item during recovery
because wrapping of the flushiter can result in false detection.

Hence that makes this "don't use flushiter" optimisation limited to
a disk format that guarantees that we don't need it. And that means
the only fix here is to limit the "no read IO on create"
optimisation to version 5 superblocks....

Reported-by: Markus Trippelsdorf 
Signed-off-by: Dave Chinner 
Reviewed-by: Mark Tinguely 
Signed-off-by: Ben Myers 

(cherry picked from commit e60896d8f2b81412421953e14d3feb14177edb56)

Merge tag 'for-linus-v3.11-rc1-2' of git://oss.sgi.com/xfs/xfs

2013-07-13T18:40:24+00:00

Pull more xfs updates from Ben Myers:
 "Here are a fix for xfs_fsr, a cleanup in bulkstat, a cleanup in
  xfs_open_by_handle, updated mount options documentation, a cleanup in
  xfs_bmapi_write, a fix for the size of dquot log reservations, a fix
  for sgid inheritance when acls are in use, a fix for cleaning up
  quotainfo structures, and some more of the work which allows group and
  project quotas to be used together.

  We had a few more in this last quota category that we might have liked
  to get in, but it looks there are still a few items that need to be
  addressed.

   - fix for xfs_fsr returning -EINVAL
   - cleanup in xfs_bulkstat
   - cleanup in xfs_open_by_handle
   - update mount options documentation
   - clean up local format handling in xfs_bmapi_write
   - fix dquot log reservations which were too small
   - fix sgid inheritance for subdirectories when default acls are in use
   - add project quota fields to various structures
   - fix teardown of quotainfo structures when quotas are turned off"

* tag 'for-linus-v3.11-rc1-2' of git://oss.sgi.com/xfs/xfs:
  xfs: Fix the logic check for all quotas being turned off
  xfs: Add pquota fields where gquota is used.
  xfs: fix sgid inheritance for subdirectories inheriting default acls [V3]
  xfs: dquot log reservations are too small
  xfs: remove local fork format handling from xfs_bmapi_write()
  xfs: update mount options documentation
  xfs: use get_unused_fd_flags(0) instead of get_unused_fd()
  xfs: clean up unused codes at xfs_bulkstat()
  xfs: use XFS_BMAP_BMDR_SPACE vs. XFS_BROOT_SIZE_ADJ

xfs: Fix the logic check for all quotas being turned off

2013-07-11T21:49:10+00:00

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: Chandra Seetharaman 
Reviewed-by: Ben Myers 
Signed-off-by: Ben Myers

xfs: Add pquota fields where gquota is used.

2013-07-11T15:35:32+00:00

Add project quota changes to all the places where group quota field
is used:
   * add separate project quota members into various structures
   * split project quota and group quotas so that instead of overriding
     the group quota members incore, the new project quota members are
     used instead
   * get rid of usage of the OQUOTA flag incore, in favor of separate
     group and project quota flags.
   * add a project dquot argument to various functions.

Not using the pquotino field from superblock yet.

Signed-off-by: Chandra Seetharaman 
Reviewed-by: Ben Myers 
Signed-off-by: Ben Myers

xfs: fix sgid inheritance for subdirectories inheriting default acls [V3]

2013-07-10T15:21:51+00:00

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: Carlos Maiolino 
Reviewed-by: Ben Myers 
Signed-off-by: Ben Myers

xfs: dquot log reservations are too small

2013-07-09T21:43:16+00:00

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: Dave Chinner 
Reviewed-by: Mark Tinguely 
Signed-off-by: Ben Myers

xfs: remove local fork format handling from xfs_bmapi_write()

2013-07-09T21:40:22+00:00

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: Dave Chinner 
Reviewed-by: Mark Tinguely 
Signed-off-by: Ben Myers

xfs: use get_unused_fd_flags(0) instead of get_unused_fd()

2013-07-09T20:53:57+00:00

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: Yann Droneaud 
Reviewed-by: Ben Myers 
Signed-off-by: Ben Myers

xfs: clean up unused codes at xfs_bulkstat()

2013-07-09T20:36:21+00:00

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: Jie Liu 
Reviewed-by: Dave Chinner 
Signed-off-by: Ben Myers

Merge tag 'for-linus-v3.11-rc1' of git://oss.sgi.com/xfs/xfs

2013-07-09T19:29:12+00:00

Pull xfs update from Ben Myers:
 "This includes several bugfixes, part of the work for project quotas
  and group quotas to be used together, performance improvements for
  inode creation/deletion, buffer readahead, and bulkstat,
  implementation of the inode change count, an inode create transaction,
  and the removal of a bunch of dead code.

  There are also some duplicate commits that you already have from the
  3.10-rc series.

   - part of the work to allow project quotas and group quotas to be
     used together
   - inode change count
   - inode create transaction
   - block queue plugging in buffer readahead and bulkstat
   - ordered log vector support
   - removal of dead code in and around xfs_sync_inode_grab,
     xfs_ialloc_get_rec, XFS_MOUNT_RETERR, XFS_ALLOCFREE_LOG_RES,
     XFS_DIROP_LOG_RES, xfs_chash, ctl_table, and
     xfs_growfs_data_private
   - don't keep silent if sunit/swidth can not be changed via mount
   - fix a leak of remote symlink blocks into the filesystem when xattrs
     are used on symlinks
   - fix for fiemap to return FIEMAP_EXTENT_UNKOWN flag on delay extents
   - part of a fix for xfs_fsr
   - disable speculative preallocation with small files
   - performance improvements for inode creates and deletes"

* tag 'for-linus-v3.11-rc1' of git://oss.sgi.com/xfs/xfs: (61 commits)
  xfs: Remove incore use of XFS_OQUOTA_ENFD and XFS_OQUOTA_CHKD
  xfs: Change xfs_dquot_acct to be a 2-dimensional array
  xfs: Code cleanup and removal of some typedef usage
  xfs: Replace macro XFS_DQ_TO_QIP with a function
  xfs: Replace macro XFS_DQUOT_TREE with a function
  xfs: Define a new function xfs_is_quota_inode()
  xfs: implement inode change count
  xfs: Use inode create transaction
  xfs: Inode create item recovery
  xfs: Inode create transaction reservations
  xfs: Inode create log items
  xfs: Introduce an ordered buffer item
  xfs: Introduce ordered log vector support
  xfs: xfs_ifree doesn't need to modify the inode buffer
  xfs: don't do IO when creating an new inode
  xfs: don't use speculative prealloc for small files
  xfs: plug directory buffer readahead
  xfs: add pluging for bulkstat readahead
  xfs: Remove dead function prototype xfs_sync_inode_grab()
  xfs: Remove the left function variable from xfs_ialloc_get_rec()
  ...