Commit Graph

195 Commits

Author SHA1 Message Date
Al Viro 8c54ca9c68 quota: constify struct path in quota_on
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-12-05 19:03:06 -05:00
Jan Kara c3b004460d quota: Remove dqonoff_mutex
The only places that were grabbing dqonoff_mutex are functions turning
quotas on and off and these are properly serialized using s_umount
semaphore. Remove dqonoff_mutex.

Signed-off-by: Jan Kara <jack@suse.cz>
2016-11-30 08:38:07 +01:00
Jan Kara ee1ac541a2 quota: Remove dqonoff_mutex from dquot_scan_active()
All callers of dquot_scan_active() now hold s_umount so we can rely on
that lock to protect us against quota state changes.

Signed-off-by: Jan Kara <jack@suse.cz>
2016-11-30 08:37:11 +01:00
Jan Kara 9d1ccbe70e quota: Use s_umount protection for quota operations
Writeback quota is protected by s_umount semaphore held for reading
because every writeback must be protected by that lock (grabbed either
by the generic writeback code or by quotactl handler). Getting next
available ID in quota file, querying quota state, setting quota
information, getting quota format are all quotactl operations protected
by s_umount semaphore held for reading grabbed in quotactl handler.

This also fixes lockdep splat about possible deadlock during filesystem
freezing where sync_filesystem() is called with page-faults already
blocked but sync_filesystem() calls into dquot_writeback_dquots() which
grabs dqonoff_mutex which ranks above i_mutex (vfs_load_quota_inode()
grabs i_mutex under dqonoff_mutex) which clearly ranks below page fault
freeze protection (e.g. via mmap_sem dependencies). The reported problem
is not a real deadlock possibility since during quota on we check
whether filesystem freezing is not in progress but still it is good to
have this fixed.

Reported-by: Ted Tso <tytso@mit.edu>
Reported-by: Eric Whitney <enwlinux@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2016-11-24 15:27:16 +01:00
Jan Kara 7d6cd73d33 quota: Hold s_umount in exclusive mode when enabling / disabling quotas
Currently we hold s_umount semaphore only in shared mode when enabling
or disabling quotas and use dqonoff_mutex for serializing quota state
changes on a filesystem and also quota state changes with other places
depending on current quota state. Using dedicated mutex for this causes
possible deadlocks during filesystem freezing (see following commit for
details) so we transition to using s_umount semaphore for the necessary
synchronization whose lock ordering is properly handled by the
filesystem freezing code. As a start grab s_umount in exclusive mode
when enabling / disabling quotas.

Signed-off-by: Jan Kara <jack@suse.cz>
2016-11-24 15:26:53 +01:00
Linus Torvalds a867d7349e Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull userns vfs updates from Eric Biederman:
 "This tree contains some very long awaited work on generalizing the
  user namespace support for mounting filesystems to include filesystems
  with a backing store.  The real world target is fuse but the goal is
  to update the vfs to allow any filesystem to be supported.  This
  patchset is based on a lot of code review and testing to approach that
  goal.

  While looking at what is needed to support the fuse filesystem it
  became clear that there were things like xattrs for security modules
  that needed special treatment.  That the resolution of those concerns
  would not be fuse specific.  That sorting out these general issues
  made most sense at the generic level, where the right people could be
  drawn into the conversation, and the issues could be solved for
  everyone.

  At a high level what this patchset does a couple of simple things:

   - Add a user namespace owner (s_user_ns) to struct super_block.

   - Teach the vfs to handle filesystem uids and gids not mapping into
     to kuids and kgids and being reported as INVALID_UID and
     INVALID_GID in vfs data structures.

  By assigning a user namespace owner filesystems that are mounted with
  only user namespace privilege can be detected.  This allows security
  modules and the like to know which mounts may not be trusted.  This
  also allows the set of uids and gids that are communicated to the
  filesystem to be capped at the set of kuids and kgids that are in the
  owning user namespace of the filesystem.

  One of the crazier corner casees this handles is the case of inodes
  whose i_uid or i_gid are not mapped into the vfs.  Most of the code
  simply doesn't care but it is easy to confuse the inode writeback path
  so no operation that could cause an inode write-back is permitted for
  such inodes (aka only reads are allowed).

  This set of changes starts out by cleaning up the code paths involved
  in user namespace permirted mounts.  Then when things are clean enough
  adds code that cleanly sets s_user_ns.  Then additional restrictions
  are added that are possible now that the filesystem superblock
  contains owner information.

  These changes should not affect anyone in practice, but there are some
  parts of these restrictions that are changes in behavior.

   - Andy's restriction on suid executables that does not honor the
     suid bit when the path is from another mount namespace (think
     /proc/[pid]/fd/) or when the filesystem was mounted by a less
     privileged user.

   - The replacement of the user namespace implicit setting of MNT_NODEV
     with implicitly setting SB_I_NODEV on the filesystem superblock
     instead.

     Using SB_I_NODEV is a stronger form that happens to make this state
     user invisible.  The user visibility can be managed but it caused
     problems when it was introduced from applications reasonably
     expecting mount flags to be what they were set to.

  There is a little bit of work remaining before it is safe to support
  mounting filesystems with backing store in user namespaces, beyond
  what is in this set of changes.

   - Verifying the mounter has permission to read/write the block device
     during mount.

   - Teaching the integrity modules IMA and EVM to handle filesystems
     mounted with only user namespace root and to reduce trust in their
     security xattrs accordingly.

   - Capturing the mounters credentials and using that for permission
     checks in d_automount and the like.  (Given that overlayfs already
     does this, and we need the work in d_automount it make sense to
     generalize this case).

  Furthermore there are a few changes that are on the wishlist:

   - Get all filesystems supporting posix acls using the generic posix
     acls so that posix_acl_fix_xattr_from_user and
     posix_acl_fix_xattr_to_user may be removed.  [Maintainability]

   - Reducing the permission checks in places such as remount to allow
     the superblock owner to perform them.

   - Allowing the superblock owner to chown files with unmapped uids and
     gids to something that is mapped so the files may be treated
     normally.

  I am not considering even obvious relaxations of permission checks
  until it is clear there are no more corner cases that need to be
  locked down and handled generically.

  Many thanks to Seth Forshee who kept this code alive, and putting up
  with me rewriting substantial portions of what he did to handle more
  corner cases, and for his diligent testing and reviewing of my
  changes"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (30 commits)
  fs: Call d_automount with the filesystems creds
  fs: Update i_[ug]id_(read|write) to translate relative to s_user_ns
  evm: Translate user/group ids relative to s_user_ns when computing HMAC
  dquot: For now explicitly don't support filesystems outside of init_user_ns
  quota: Handle quota data stored in s_user_ns in quota_setxquota
  quota: Ensure qids map to the filesystem
  vfs: Don't create inodes with a uid or gid unknown to the vfs
  vfs: Don't modify inodes with a uid or gid unknown to the vfs
  cred: Reject inodes with invalid ids in set_create_file_as()
  fs: Check for invalid i_uid in may_follow_link()
  vfs: Verify acls are valid within superblock's s_user_ns.
  userns: Handle -1 in k[ug]id_has_mapping when !CONFIG_USER_NS
  fs: Refuse uid/gid changes which don't map into s_user_ns
  selinux: Add support for unprivileged mounts from user namespaces
  Smack: Handle labels consistently in untrusted mounts
  Smack: Add support for unprivileged mounts from user namespaces
  fs: Treat foreign mounts as nosuid
  fs: Limit file caps to the user namespace of the super block
  userns: Remove the now unnecessary FS_USERNS_DEV_MOUNT flag
  userns: Remove implicit MNT_NODEV fragility.
  ...
2016-07-29 15:54:19 -07:00
Eric W. Biederman 5c0048280b dquot: For now explicitly don't support filesystems outside of init_user_ns
Mostly supporting filesystems outside of init_user_ns is
s/&init_usre_ns/dquot->dq_sb->s_user_ns/.  An actual need for
supporting quotas on filesystems outside of s_user_ns is quite a ways
away and to be done responsibily needs an audit on what can happen
with hostile quota files.  Until that audit is complete don't attempt
to support quota files on filesystems outside of s_user_ns.

Cc: Jan Kara <jack@suse.cz>
Acked-by: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2016-07-05 15:12:39 -05:00
Eric W. Biederman d49d37624a quota: Ensure qids map to the filesystem
Introduce the helper qid_has_mapping and use it to ensure that the
quota system only considers qids that map to the filesystems
s_user_ns.

In practice for quota supporting filesystems today this is the exact
same check as qid_valid.  As only 0xffffffff aka (qid_t)-1 does not
map into init_user_ns.

Replace the qid_valid calls with qid_has_mapping as values come in
from userspace.  This is harmless today and it prepares the quota
system to work on filesystems with quotas but mounted by unprivileged
users.

Call qid_has_mapping from dqget.  This ensures the passed in qid has a
prepresentation on the underlying filesystem.  Previously this was
unnecessary as filesystesm never had qids that could not map.  With
the introduction of filesystems outside of s_user_ns this will not
remain true.

All of this ensures the quota code never has to deal with qids that
don't map to the underlying filesystem.

Cc: Jan Kara <jack@suse.cz>
Acked-by: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2016-07-05 15:12:05 -05:00
Arnd Bergmann e008bb6134 quota: use time64_t internally
The quota subsystem has two formats, the old v1 format using architecture
specific time_t values on the on-disk format, while the v2 format
(introduced in Linux 2.5.16 and 2.4.22) uses fixed 64-bit little-endian.

While there is no future for the v1 format beyond y2038, the v2 format
is almost there on 32-bit architectures, as both the user interface
and the on-disk format use 64-bit timestamps, just not the time_t
inbetween.

This changes the internal representation to use time64_t, which will
end up doing the right thing everywhere for v2 format.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jan Kara <jack@suse.cz>
2016-06-19 18:09:31 +02:00
Jan Kara 17e8a8936c quota: Handle Q_GETNEXTQUOTA when quota is disabled
Currently we oopsed when Q_GETNEXTQUOTA got called when quota was
disabled. Properly check whether quota is enabled for the filesystem
before calling into quota format handler.

Reported-by: Ted Tso <tytso@mit.edu>
Signed-off-by: Jan Kara <jack@suse.cz>
2016-03-29 17:20:10 +02:00
Linus Torvalds 77d913178c Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs
Pull UDF and quota updates from Jan Kara:
 "This contains a rewrite of UDF handling of filename encoding to fix
  remaining overflow issues from Andrew Gabbasov and quota changes to
  support new Q_[X]GETNEXTQUOTA quotactl for VFS quota formats"

* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
  quota: Fix possible GPF due to uninitialised pointers
  ext4: Make Q_GETNEXTQUOTA work for quota in hidden inodes
  quota: Forbid Q_GETQUOTA and Q_GETNEXTQUOTA for frozen filesystem
  quota: Fix possible races during quota loading
  ocfs2: Implement get_next_id()
  quota_v2: Implement get_next_id() for V2 quota format
  quota: Add support for ->get_nextdqblk() for VFS quota
  udf: Merge linux specific translation into CS0 conversion function
  udf: Remove struct ustr as non-needed intermediate storage
  udf: Use separate buffer for copying split names
  udf: Adjust UDF_NAME_LEN to better reflect actual restrictions
  udf: Join functions for UTF8 and NLS conversions
  udf: Parameterize output length in udf_put_filename
  quota: Allow Q_GETQUOTA for frozen filesystem
  quota: Fixup comments about return value of Q_[X]GETNEXTQUOTA
2016-03-21 12:22:37 -07:00
Al Viro e12a4e8a04 quota: use lookup_one_len_unlocked()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-03-14 00:16:48 -04:00
Nikolay Borisov ab73ef4639 quota: Fix possible GPF due to uninitialised pointers
When dqget() in __dquot_initialize() fails e.g. due to IO error,
__dquot_initialize() will pass an array of uninitialized pointers to
dqput_all() and thus can lead to deference of random data. Fix the
problem by properly initializing the array.

CC: stable@vger.kernel.org
Signed-off-by: Nikolay Borisov <kernel@kyup.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2016-03-03 11:01:58 +01:00
Jan Kara 044c9b6753 quota: Fix possible races during quota loading
When loading new quota structure from disk, there is a possibility caller
of dqget() will see uninitialized data due to CPU reordering loads or
stores - loads from dquot can be reordered before test of DQ_ACTIVE_B
bit or setting of this bit could be reordered before filling of the
structure. Fix the issue by adding proper memory barriers.

Signed-off-by: Jan Kara <jack@suse.cz>
2016-02-18 13:34:41 +01:00
Jan Kara be6257b251 quota: Add support for ->get_nextdqblk() for VFS quota
Add infrastructure for supporting get_nextdqblk() callback for VFS
quotas. Translate the operation into a callback to appropriate
filesystem and consequently to quota format callback.

Signed-off-by: Jan Kara <jack@suse.cz>
2016-02-09 13:05:23 +01:00
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
Paul Gortmaker 331221fac7 fs: make quota/dquot.c explicitly non-modular
The Kconfig currently controlling compilation of this code is:

config QUOTA
        bool "Quota support"

...meaning that it currently is not being built as a module by anyone.

Lets remove the couple traces of modularity so that when reading the
driver there is no doubt it is builtin-only.

Since module_init translates to device_initcall in the non-modular
case, the init ordering gets bumped to one level earlier when we
use the more appropriate fs_initcall here.  However we've made similar
changes before without any fallout and none is expected here either.

We don't delete module.h because the code in turn tries to load other
modules as appropriate and so it still needs that header.

Cc: Jan Kara <jack@suse.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2015-12-14 12:04:34 +01:00
Linus Torvalds 7d9071a095 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs updates from Al Viro:
 "In this one:

   - d_move fixes (Eric Biederman)

   - UFS fixes (me; locking is mostly sane now, a bunch of bugs in error
     handling ought to be fixed)

   - switch of sb_writers to percpu rwsem (Oleg Nesterov)

   - superblock scalability (Josef Bacik and Dave Chinner)

   - swapon(2) race fix (Hugh Dickins)"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (65 commits)
  vfs: Test for and handle paths that are unreachable from their mnt_root
  dcache: Reduce the scope of i_lock in d_splice_alias
  dcache: Handle escaped paths in prepend_path
  mm: fix potential data race in SyS_swapon
  inode: don't softlockup when evicting inodes
  inode: rename i_wb_list to i_io_list
  sync: serialise per-superblock sync operations
  inode: convert inode_sb_list_lock to per-sb
  inode: add hlist_fake to avoid the inode hash lock in evict
  writeback: plug writeback at a high level
  change sb_writers to use percpu_rw_semaphore
  shift percpu_counter_destroy() into destroy_super_work()
  percpu-rwsem: kill CONFIG_PERCPU_RWSEM
  percpu-rwsem: introduce percpu_rwsem_release() and percpu_rwsem_acquire()
  percpu-rwsem: introduce percpu_down_read_trylock()
  document rwsem_release() in sb_wait_write()
  fix the broken lockdep logic in __sb_start_write()
  introduce __sb_writers_{acquired,release}() helpers
  ufs_inode_get{frag,block}(): get rid of 'phys' argument
  ufs_getfrag_block(): tidy up a bit
  ...
2015-09-05 20:34:28 -07:00
Dave Chinner 74278da9f7 inode: convert inode_sb_list_lock to per-sb
The process of reducing contention on per-superblock inode lists
starts with moving the locking to match the per-superblock inode
list. This takes the global lock out of the picture and reduces the
contention problems to within a single filesystem. This doesn't get
rid of contention as the locks still have global CPU scope, but it
does isolate operations on different superblocks form each other.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Tested-by: Dave Chinner <dchinner@redhat.com>
2015-08-17 18:39:46 -04:00
Jan Kara 6184fc0b8d quota: Propagate error from ->acquire_dquot()
Currently when some error happened in ->acquire_dquot(), dqget() just
returned NULL. That was indistinguishable from a case when e.g. someone
run quotaoff and so was generally silently ignored. However
->acquire_dquot() can fail because of ENOSPC or EIO in which case user
should better know. So propagate error up from ->acquire_dquot properly.

Signed-off-by: Jan Kara <jack@suse.cz>
2015-07-23 20:59:10 +02:00
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 dea655c28a VFS: fs library helpers: d_inode() annotations
library helpers called by filesystem drivers on their own inodes

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-15 15:06:58 -04:00
Li Xi 847aac644e vfs: Add general support to enforce project quota limits
This patch adds support for a new quota type PRJQUOTA for project quota
enforcement. Also a new method get_projid() is added into dquot_operations
structure.

Signed-off-by: Li Xi <lixi@ddn.com>
Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jan Kara <jack@suse.cz>
2015-03-18 21:55:08 +01:00
Jan Kara 7dca0548a2 Merge branch 'quota_interface' into for_next_testing 2015-03-16 10:26:41 +01:00
Konstantin Khlebnikov 5bcd3b6f63 quota: optimize i_dquot access
Remove redundant calls of i_dquot(), keep pointer in local variable.

add/remove: 0/0 grow/shrink: 3/7 up/down: 40/-278 (-238)
function                                     old     new   delta
__dquot_free_space                           734     750     +16
__dquot_alloc_space                          484     500     +16
dquot_free_inode                             324     332      +8
dquot_drop                                    82      69     -13
vfs_load_quota_inode                        1357    1341     -16
dquot_reclaim_space_nodirty                  348     316     -32
dquot_disable                               1980    1944     -36
dquot_claim_space_nodirty                    354     314     -40
__dquot_drop                                 125      83     -42
__dquot_initialize                           522     423     -99

Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: Jan Kara <jack@suse.cz>
2015-03-04 16:42:44 +01:00
Jan Kara 5eacb2ac02 quota: Make ->set_info use structure with neccesary info to VFS and XFS
Change ->set_info to take new qc_info structure which contains all the
necessary information both for XFS and VFS. Convert Q_SETINFO handler
to use this structure.

Signed-off-by: Jan Kara <jack@suse.cz>
2015-03-04 16:06:38 +01:00
Jan Kara 0a240339a8 quota: Make VFS quotas use new interface for getting quota info
Create new internal interface for getting information about quota which
contains everything needed for both VFS quotas and XFS quotas. Make VFS
use this and hook it up to Q_GETINFO.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
2015-03-04 16:06:34 +01:00
Jan Kara b10a08194c quota: Store maximum space limit in bytes
Currently maximum space limit quota format supports is in blocks however
since we store space limits in bytes, this is somewhat confusing. So
store the maximum limit in bytes as well. Also rename the field to match
the new unit and related inode field to match the new naming scheme.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
2015-01-30 12:51:21 +01:00
Jan Kara 3e2af67e66 quota: Add ->quota_{enable,disable} callbacks for VFS quotas
Add functions which translate ->quota_enable / ->quota_disable calls
into appropriate changes in VFS quota. This will enable filesystems
supporting VFS quota files in system inodes to be controlled via
Q_XQUOTA[ON|OFF] quotactls for better userspace compatibility.

Also provide a vector for quotactl using these functions which can be
used by filesystems with quota files stored in hidden system files.

Signed-off-by: Jan Kara <jack@suse.cz>
2015-01-30 12:50:32 +01:00
Jan Kara 1cd6b7be92 Merge branch 'for_linus' into for_next 2015-01-30 10:16:33 +01:00
Jan Kara 14bf61ffe6 quota: Switch ->get_dqblk() and ->set_dqblk() to use bytes as space units
Currently ->get_dqblk() and ->set_dqblk() use struct fs_disk_quota which
tracks space limits and usage in 512-byte blocks. However VFS quotas
track usage in bytes (as some filesystems require that) and we need to
somehow pass this information. Upto now it wasn't a problem because we
didn't do any unit conversion (thus VFS quota routines happily stuck
number of bytes into d_bcount field of struct fd_disk_quota). Only if
you tried to use Q_XGETQUOTA or Q_XSETQLIM for VFS quotas (or Q_GETQUOTA
/ Q_SETQUOTA for XFS quotas), you got bogus results. Hardly anyone
tried this but reportedly some Samba users hit the problem in practice.
So when we want interfaces compatible we need to fix this.

We bite the bullet and define another quota structure used for passing
information from/to ->get_dqblk()/->set_dqblk. It's somewhat sad we have
to have more conversion routines in fs/quota/quota.c and another copying
of quota structure slows down getting of quota information by about 2%
but it seems cleaner than overloading e.g. units of d_bcount to bytes.

CC: stable@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
2015-01-28 09:01:40 +01:00
Jan Kara ca6cb0918e quota: Verify flags passed to Q_SETINFO
Currently flags passed via Q_SETINFO were just stored. This makes it
hard to add new flags since in theory userspace could be just setting /
clearing random flags. Since currently there is only one userspace
settable flag and that is somewhat obscure flags only for ancient v1
quota format, I'm reasonably sure noone operates these flags and
hopefully we are fine just adding the check that passed flags are sane.
If we indeed find some userspace program that gets broken by the strict
check, we can always remove it again.

Signed-off-by: Jan Kara <jack@suse.cz>
2015-01-21 19:21:31 +01:00
Jan Kara 9c45101e88 quota: Cleanup flags definitions
Currently all quota flags were defined just in kernel-private headers.
Export flags readable / writeable from userspace to userspace via
include/uapi/linux/quota.h.

Signed-off-by: Jan Kara <jack@suse.cz>
2015-01-21 19:21:30 +01:00
Jan Kara 75cbe701a4 vfs: Remove i_dquot field from inode
All filesystems using VFS quotas are now converted to use their private
i_dquot fields. Remove the i_dquot field from generic inode structure.

Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
2014-11-10 10:06:18 +01:00
Jan Kara 2d0fa46791 quota: Use function to provide i_dquot pointers
i_dquot array is used by relatively few filesystems (ext?, ocfs2, jfs,
reiserfs) so it is beneficial to move this array to fs-private part of
the inode. We cannot just pass quota pointers from filesystems to quota
functions because during quotaon and quotaoff we have to traverse list
of all inodes and manipulate i_dquot pointers for each inode. So we
provide a function which generic quota code can use to get pointer to
the i_dquot array from the filesystem.

Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
2014-11-10 10:06:09 +01:00
Jan Kara 6bab3596bb quota: Remove const from function declarations
We don't use const through VFS too much so just remove it from quota
function declarations.

Signed-off-by: Jan Kara <jack@suse.cz>
2014-11-10 10:06:07 +01:00
Anton Blanchard 19858e7bdc quota: Add log level to printk
JK: Added VFS: prefix to the message when changing it to make it more
    standard.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Jan Kara <jack@suse.cz>
2014-11-04 12:01:06 +01:00
Jan Kara 474d2605d1 quota: Properly return errors from dquot_writeback_dquots()
Due to a switched left and right side of an assignment,
dquot_writeback_dquots() never returned error. This could result in
errors during quota writeback to not be reported to userspace properly.
Fix it.

CC: stable@vger.kernel.org
Coverity-id: 1226884
Signed-off-by: Jan Kara <jack@suse.cz>
2014-10-22 09:08:03 +02:00
Tejun Heo 908c7f1949 percpu_counter: add @gfp to percpu_counter_init()
Percpu allocator now supports allocation mask.  Add @gfp to
percpu_counter_init() so that !GFP_KERNEL allocation masks can be used
with percpu_counters too.

We could have left percpu_counter_init() alone and added
percpu_counter_init_gfp(); however, the number of users isn't that
high and introducing _gfp variants to all percpu data structures would
be quite ugly, so let's just do the conversion.  This is the one with
the most users.  Other percpu data structures are a lot easier to
convert.

This patch doesn't make any functional difference.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Jan Kara <jack@suse.cz>
Acked-by: "David S. Miller" <davem@davemloft.net>
Cc: x86@kernel.org
Cc: Jens Axboe <axboe@kernel.dk>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
2014-09-08 09:51:29 +09:00
Niu Yawei b9ba6f94b2 quota: remove dqptr_sem
Remove dqptr_sem to make quota code scalable: Remove the dqptr_sem,
accessing inode->i_dquot now protected by dquot_srcu, and changing
inode->i_dquot is now serialized by dq_data_lock.

Signed-off-by: Lai Siyao <lai.siyao@intel.com>
Signed-off-by: Niu Yawei <yawei.niu@intel.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2014-07-15 22:40:22 +02:00
Niu Yawei 9eb6463f31 quota: simplify remove_inode_dquot_ref()
Simplify the remove_inode_dquot_ref() to make it more obvious
that now we keep one reference for each dquot from inodes.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Niu Yawei <yawei.niu@intel.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2014-07-15 22:40:21 +02:00
Niu Yawei 1ea06bec78 quota: avoid unnecessary dqget()/dqput() calls
Avoid unnecessary dqget()/dqput() calls in __dquot_initialize(),
that will introduce global lock contention otherwise.

Signed-off-by: Lai Siyao <lai.siyao@intel.com>
Signed-off-by: Niu Yawei <yawei.niu@intel.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2014-07-15 22:40:21 +02:00
Niu Yawei d68aab6b8f quota: missing lock in dqcache_shrink_scan()
Commit 1ab6c4997e (fs: convert fs shrinkers to new scan/count API)
accidentally removed locking from quota shrinker. Fix it -
dqcache_shrink_scan() should use dq_list_lock to protect the
scan on free_dquots list.

CC: stable@vger.kernel.org
Fixes: 1ab6c4997e
Signed-off-by: Niu Yawei <yawei.niu@intel.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2014-07-15 22:36:18 +02:00
Jan Kara 9f985cb6c4 quota: provide function to grab quota structure reference
Provide dqgrab() function to get quota structure reference when we are
sure it already has at least one active reference.  Make use of this
function inside quota code.

Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Mark Fasheh <mfasheh@suse.de>
Reviewed-by: Srinivas Eeda <srinivas.eeda@oracle.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-03 16:20:54 -07:00
Jan Kara 1362f4ea20 quota: Fix race between dqput() and dquot_scan_active()
Currently last dqput() can race with dquot_scan_active() causing it to
call callback for an already deactivated dquot. The race is as follows:

CPU1					CPU2
  dqput()
    spin_lock(&dq_list_lock);
    if (atomic_read(&dquot->dq_count) > 1) {
     - not taken
    if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) {
      spin_unlock(&dq_list_lock);
      ->release_dquot(dquot);
        if (atomic_read(&dquot->dq_count) > 1)
         - not taken
					  dquot_scan_active()
					    spin_lock(&dq_list_lock);
					    if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags))
					     - not taken
					    atomic_inc(&dquot->dq_count);
					    spin_unlock(&dq_list_lock);
        - proceeds to release dquot
					    ret = fn(dquot, priv);
					     - called for inactive dquot

Fix the problem by making sure possible ->release_dquot() is finished by
the time we call the callback and new calls to it will notice reference
dquot_scan_active() has taken and bail out.

CC: stable@vger.kernel.org # >= 2.6.29
Signed-off-by: Jan Kara <jack@suse.cz>
2014-02-20 21:57:04 +01:00
Dave Chinner 1ab6c4997e fs: convert fs shrinkers to new scan/count API
Convert the filesystem shrinkers to use the new API, and standardise some
of the behaviours of the shrinkers at the same time.  For example,
nr_to_scan means the number of objects to scan, not the number of objects
to free.

I refactored the CIFS idmap shrinker a little - it really needs to be
broken up into a shrinker per tree and keep an item count with the tree
root so that we don't need to walk the tree every time the shrinker needs
to count the number of objects in the tree (i.e.  all the time under
memory pressure).

[glommer@openvz.org: fixes for ext4, ubifs, nfs, cifs and glock. Fixes are needed mainly due to new code merged in the tree]
[assorted fixes folded in]
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Glauber Costa <glommer@openvz.org>
Acked-by: Mel Gorman <mgorman@suse.de>
Acked-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Acked-by: Jan Kara <jack@suse.cz>
Acked-by: Steven Whitehouse <swhiteho@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Cc: Arve Hjønnevåg <arve@android.com>
Cc: Carlos Maiolino <cmaiolino@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: David Rientjes <rientjes@google.com>
Cc: Gleb Natapov <gleb@redhat.com>
Cc: Greg Thelen <gthelen@google.com>
Cc: J. Bruce Fields <bfields@redhat.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Kent Overstreet <koverstreet@google.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Thomas Hellstrom <thellstrom@vmware.com>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-09-10 18:56:31 -04:00
Glauber Costa 55f841ce93 super: fix calculation of shrinkable objects for small numbers
The sysctl knob sysctl_vfs_cache_pressure is used to determine which
percentage of the shrinkable objects in our cache we should actively try
to shrink.

It works great in situations in which we have many objects (at least more
than 100), because the aproximation errors will be negligible.  But if
this is not the case, specially when total_objects < 100, we may end up
concluding that we have no objects at all (total / 100 = 0, if total <
100).

This is certainly not the biggest killer in the world, but may matter in
very low kernel memory situations.

Signed-off-by: Glauber Costa <glommer@openvz.org>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Cc: Arve Hjønnevåg <arve@android.com>
Cc: Carlos Maiolino <cmaiolino@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: David Rientjes <rientjes@google.com>
Cc: Gleb Natapov <gleb@redhat.com>
Cc: Greg Thelen <gthelen@google.com>
Cc: J. Bruce Fields <bfields@redhat.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Kent Overstreet <koverstreet@google.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Thomas Hellstrom <thellstrom@vmware.com>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-09-10 18:56:29 -04:00
Jan Kara 1c8924eb10 quota: provide interface for readding allocated space into reserved space
ext4 needs to convert allocated (metadata) blocks back into blocks
reserved for delayed allocation. Add functions into quota code for
supporting such operation.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2013-08-17 09:32:32 -04:00
Joe Perches e628753bf9 quota: Convert use of typedef ctl_table to struct ctl_table
This typedef is unnecessary and should just be removed.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2013-07-04 19:22:55 +02:00
Jeff Mahoney 68ac8bfb6a quota: add missing use of dq_data_lock in __dquot_initialize
The bulk of __dquot_initialize runs under the dqptr_sem which
protects the inode->i_dquot pointers. It doesn't protect the
dereferenced contents, though. Those are protected by the
dq_data_lock, which is missing around the dquot_resv_space call.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2013-03-11 22:05:56 +01:00
Jan Kara 6c29c50fda quota: Silence warning about PRJQUOTA not being handled in need_print_warning()
PRJQUOTA value of quota type should never reach need_print_warning() since XFS
(which is the only fs which uses that type) doesn't use generic functions
calling this function. Anyway, add PRJQUOTA case to the switch to make gcc
happy.

Signed-off-by: Jan Kara <jack@suse.cz>
2012-10-09 23:37:38 +02:00
Linus Torvalds 437589a74b Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace
Pull user namespace changes from Eric Biederman:
 "This is a mostly modest set of changes to enable basic user namespace
  support.  This allows the code to code to compile with user namespaces
  enabled and removes the assumption there is only the initial user
  namespace.  Everything is converted except for the most complex of the
  filesystems: autofs4, 9p, afs, ceph, cifs, coda, fuse, gfs2, ncpfs,
  nfs, ocfs2 and xfs as those patches need a bit more review.

  The strategy is to push kuid_t and kgid_t values are far down into
  subsystems and filesystems as reasonable.  Leaving the make_kuid and
  from_kuid operations to happen at the edge of userspace, as the values
  come off the disk, and as the values come in from the network.
  Letting compile type incompatible compile errors (present when user
  namespaces are enabled) guide me to find the issues.

  The most tricky areas have been the places where we had an implicit
  union of uid and gid values and were storing them in an unsigned int.
  Those places were converted into explicit unions.  I made certain to
  handle those places with simple trivial patches.

  Out of that work I discovered we have generic interfaces for storing
  quota by projid.  I had never heard of the project identifiers before.
  Adding full user namespace support for project identifiers accounts
  for most of the code size growth in my git tree.

  Ultimately there will be work to relax privlige checks from
  "capable(FOO)" to "ns_capable(user_ns, FOO)" where it is safe allowing
  root in a user names to do those things that today we only forbid to
  non-root users because it will confuse suid root applications.

  While I was pushing kuid_t and kgid_t changes deep into the audit code
  I made a few other cleanups.  I capitalized on the fact we process
  netlink messages in the context of the message sender.  I removed
  usage of NETLINK_CRED, and started directly using current->tty.

  Some of these patches have also made it into maintainer trees, with no
  problems from identical code from different trees showing up in
  linux-next.

  After reading through all of this code I feel like I might be able to
  win a game of kernel trivial pursuit."

Fix up some fairly trivial conflicts in netfilter uid/git logging code.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (107 commits)
  userns: Convert the ufs filesystem to use kuid/kgid where appropriate
  userns: Convert the udf filesystem to use kuid/kgid where appropriate
  userns: Convert ubifs to use kuid/kgid
  userns: Convert squashfs to use kuid/kgid where appropriate
  userns: Convert reiserfs to use kuid and kgid where appropriate
  userns: Convert jfs to use kuid/kgid where appropriate
  userns: Convert jffs2 to use kuid and kgid where appropriate
  userns: Convert hpfs to use kuid and kgid where appropriate
  userns: Convert btrfs to use kuid/kgid where appropriate
  userns: Convert bfs to use kuid/kgid where appropriate
  userns: Convert affs to use kuid/kgid wherwe appropriate
  userns: On alpha modify linux_to_osf_stat to use convert from kuids and kgids
  userns: On ia64 deal with current_uid and current_gid being kuid and kgid
  userns: On ppc convert current_uid from a kuid before printing.
  userns: Convert s390 getting uid and gid system calls to use kuid and kgid
  userns: Convert s390 hypfs to use kuid and kgid where appropriate
  userns: Convert binder ipc to use kuids
  userns: Teach security_path_chown to take kuids and kgids
  userns: Add user namespace support to IMA
  userns: Convert EVM to deal with kuids and kgids in it's hmac computation
  ...
2012-10-02 11:11:09 -07:00
Eric W. Biederman 1a06d420ce userns: Convert quota
Now that the type changes are done, here is the final set of
changes to make the quota code work when user namespaces are enabled.

Small cleanups and fixes to make the code build when user namespaces
are enabled.

Cc: Jan Kara <jack@suse.cz>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2012-09-18 01:01:42 -07:00
Eric W. Biederman 7b9c7321ca userns: Convert struct dquot_warn
Convert w_dq_id to be a struct kquid and remove the now unncessary
w_dq_type.

This is a simple conversion and enough other places have already
been converted that this actually reduces the code complexity
by a little bit, when removing now unnecessary type conversions.

Cc: Jan Kara <jack@suse.cz>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2012-09-18 01:01:42 -07:00
Eric W. Biederman 4c376dcae8 userns: Convert struct dquot dq_id to be a struct kqid
Change struct dquot dq_id to a struct kqid and remove the now
unecessary dq_type.

Make minimal changes to dquot, quota_tree, quota_v1, quota_v2, ext3,
ext4, and ocfs2 to deal with the change in quota structures and
signatures.  The ocfs2 changes are larger than most because of the
extensive tracing throughout the ocfs2 quota code that prints out
dq_id.

quota_tree.c:get_index is modified to take a struct kqid instead of a
qid_t because all of it's callers pass in dquot->dq_id and it allows
me to introduce only a single conversion.

The rest of the changes are either just replacing dq_type with dq_id.type,
adding conversions to deal with the change in type and occassionally
adding qid_eq to allow quota id comparisons in a user namespace safe way.

Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Jan Kara <jack@suse.cz>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: Theodore Tso <tytso@mit.edu>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2012-09-18 01:01:41 -07:00
Eric W. Biederman aca645a6a5 userns: Modify dqget to take struct kqid
Modify dqget to take struct kqid instead of a type and an identifier
pair.

Modify the callers of dqget in ocfs2 and dquot to take generate
a struct kqid so they can continue to call dqget.  The conversion
to create struct kqid should all be the final conversions that
are needed in those code paths.

Cc: Jan Kara <jack@suse.cz>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2012-09-18 01:01:40 -07:00
Eric W. Biederman 431f19744d userns: Convert quota netlink aka quota_send_warning
Modify quota_send_warning to take struct kqid instead a type and
identifier pair.

When sending netlink broadcasts always convert uids and quota
identifiers into the intial user namespace.  There is as yet no way to
send a netlink broadcast message with different contents to receivers
in different namespaces, so for the time being just map all of the
identifiers into the initial user namespace which preserves the
current behavior.

Change the callers of quota_send_warning in gfs2, xfs and dquot
to generate a struct kqid to pass to quota send warning.  When
all of the user namespaces convesions are complete a struct kqid
values will be availbe without need for conversion, but a conversion
is needed now to avoid needing to convert everything at once.

Cc: Ben Myers <bpm@sgi.com>
Cc: Alex Elder <elder@kernel.org>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2012-09-18 01:01:40 -07:00
Eric W. Biederman 74a8a10378 userns: Convert qutoactl
Update the quotactl user space interface to successfull compile with
user namespaces support enabled and to hand off quota identifiers to
lower layers of the kernel in struct kqid instead of type and qid
pairs.

The quota on function is not converted because while it takes a quota
type and an id.  The id is the on disk quota format to use, which
is something completely different.

The signature of two struct quotactl_ops methods were changed to take
struct kqid argumetns get_dqblk and set_dqblk.

The dquot, xfs, and ocfs2 implementations of get_dqblk and set_dqblk
are minimally changed so that the code continues to work with
the change in parameter type.

This is the first in a series of changes to always store quota
identifiers in the kernel in struct kqid and only use raw type and qid
values when interacting with on disk structures or userspace.  Always
using struct kqid internally makes it hard to miss places that need
conversion to or from the kernel internal values.

Cc: Jan Kara <jack@suse.cz>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Ben Myers <bpm@sgi.com>
Cc: Alex Elder <elder@kernel.org>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2012-09-18 01:01:39 -07:00
Jeff Liu 6ea2eea1fa quota: Move down dqptr_sem read after initializing default warn[] type at __dquot_alloc_space().
sb->s_dqopt->dqptr_sem is used to serialize ops using pointers from inode to
dquots.  But for __dquot_alloc_space(), it could be safely moved down after the
default warn[] array got initialized.

Signed-off-by: Jie Liu <jeff.liu@oracle.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2012-08-15 00:22:57 +02:00
Linus Torvalds 08d9329c29 Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs
Pull misc udf, ext2, ext3, and isofs fixes from Jan Kara:
 "Assorted, mostly trivial, fixes for udf, ext2, ext3, and isofs.  I'm
  on vacation and scarcely checking email since we are expecting baby
  any day now but these fixes should be safe to go in and I don't want
  to delay them unnecessarily."

* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
  udf: avoid info leak on export
  isofs: avoid info leak on export
  udf: Improve table length check to avoid possible overflow
  ext3: Check return value of blkdev_issue_flush()
  jbd: Check return value of blkdev_issue_flush()
  udf: Do not decrement i_blocks when freeing indirect extent block
  udf: Fix memory leak when mounting
  ext2: cleanup the confused goto label
  UDF: Remove unnecessary variable "offset" from udf_fill_inode
  udf: stop using s_dirt
  ext3: force ro mount if ext3_setup_super() fails
  quota: fix checkpatch.pl warning by replacing <asm/uaccess.h> with <linux/uaccess.h>
2012-07-24 17:40:44 -07:00
Jan Kara ceed17236a quota: Split dquot_quota_sync() to writeback and cache flushing part
Split off part of dquot_quota_sync() which writes dquots into a quota file
to a separate function. In the next patch we will use the function from
filesystems and we do not want to abuse ->quota_sync quotactl callback more
than necessary.

Acked-by: Steven Whitehouse <swhiteho@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-22 23:58:19 +04:00
Jeff Liu f3da93105b quota: fix checkpatch.pl warning by replacing <asm/uaccess.h> with <linux/uaccess.h>
checkpatch.pl warns:

"WARNING: Use #include <linux/uaccess.h> instead of <asm/uaccess.h>"

Below patch fixes it.

Signed-off-by: Jie Liu <jeff.liu@oracle.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2012-07-09 12:03:11 +02:00
Jan Kara a80b12c3d0 quota: Get rid of nested I_MUTEX_QUOTA locking subclass
So far i_mutex was ranking above dqonoff_mutex and i_mutex on quota files
was special and ranking below dqonoff_mutex (and several other locks).
However there's no real need for i_mutex on quota files to be special.
IO on quota files is serialized by dqio_mutex anyway so we don't need to
take i_mutex when writing to quota files. Other places where we take i_mutex
on quota file can accomodate standard i_mutex lock ranking, we only need
to change the lock ranking to be dqonoff_mutex > i_mutex which is a matter
of changing documentation because there's no place which would enforce
ordering in the other direction.

Signed-off-by: Jan Kara <jack@suse.cz>
2012-05-15 23:34:39 +02:00
Jan Kara f9ef178412 quota: Use precomputed value of sb_dqopt in dquot_quota_sync
Signed-off-by: Jan Kara <jack@suse.cz>
2012-05-15 23:34:39 +02:00
Jan Kara d7e9711760 quota: Fix double lock in add_dquot_ref() with CONFIG_QUOTA_DEBUG
When CONFIG_QUOTA_DEBUG is enabled we call inode_get_rsv_space() from
add_dquot_ref() while holding i_lock. But inode_get_rsv_space() is trying
to get i_lock as well resulting in double lock.

Fix the problem by moving inode_get_rsv_space() call out of i_lock.

Reported-and-analyzed-by: Jie Liu <jeff.liu@oracle.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2012-05-15 23:34:37 +02:00
Linus Torvalds 9a7259d5c8 Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs
Pull ext3, UDF, and quota fixes from Jan Kara:
 "A couple of ext3 & UDF fixes and also one improvement in quota
  locking."

* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
  ext3: fix start and len arguments handling in ext3_trim_fs()
  udf: Fix deadlock in udf_release_file()
  udf: Fix file entry logicalBlocksRecorded
  udf: Fix handling of i_blocks
  quota: Make quota code not call tty layer with dqptr_sem held
  udf: Init/maintain file entry checkpoint field
  ext3: Update ctime in ext3_splice_branch() only when needed
  ext3: Don't call dquot_free_block() if we don't update anything
  udf: Remove unnecessary OOM messages
2012-03-28 10:00:14 -07:00
Jan Kara bf097aaff4 quota: Make quota code not call tty layer with dqptr_sem held
dqptr_sem can be called from slab reclaim. tty layer uses GFP_KERNEL mask for
allocation so it can end up calling slab reclaim. Given quota code can call
into tty layer to print warning this creates possibility for lock inversion
between tty->atomic_write_lock and dqptr_sem.

Using direct printing of warnings from quota layer is obsolete but since it's
easy enough to change quota code to not hold any locks when printing warnings,
let's just do it. It seems like a good thing to do even when we use netlink
layer to transmit warnings to userspace.

Reported-by: Markus <M4rkusXXL@web.de>
Signed-off-by: Jan Kara <jack@suse.cz>
2012-02-29 21:53:47 +01:00
Al Viro 4040153087 security: trim security.h
Trim security.h

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: James Morris <jmorris@namei.org>
2012-02-14 10:45:42 +11:00
Jan Kara 46fe44ce87 quota: Pass information that quota is stored in system file to userspace
Quota tools need to know whether quota is stored in a system file or in
classical aquota.{user|group} files. So pass this information as a flag
in GETINFO quotactl.

Signed-off-by: Jan Kara <jack@suse.cz>
2012-01-12 13:09:09 +01:00
Al Viro d8c9584ea2 vfs: prefer ->dentry->d_sb to ->mnt->mnt_sb
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-06 23:16:53 -05:00
Al Viro ff01bb4832 fs: move code out of buffer.c
Move invalidate_bdev, block_sync_page into fs/block_dev.c.  Export
kill_bdev as well, so brd doesn't have to open code it.  Reduce
buffer_head.h requirement accordingly.

Removed a rather large comment from invalidate_bdev, as it looked a bit
obsolete to bother moving.  The small comment replacing it says enough.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03 22:54:07 -05:00
Ying Han 1495f230fa vmscan: change shrinker API by passing shrink_control struct
Change each shrinker's API by consolidating the existing parameters into
shrink_control struct.  This will simplify any further features added w/o
touching each file of shrinker.

[akpm@linux-foundation.org: fix build]
[akpm@linux-foundation.org: fix warning]
[kosaki.motohiro@jp.fujitsu.com: fix up new shrinker API]
[akpm@linux-foundation.org: fix xfs warning]
[akpm@linux-foundation.org: update gfs2]
Signed-off-by: Ying Han <yinghan@google.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Minchan Kim <minchan.kim@gmail.com>
Acked-by: Pavel Emelyanov <xemul@openvz.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Acked-by: Rik van Riel <riel@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Hugh Dickins <hughd@google.com>
Cc: Dave Hansen <dave@linux.vnet.ibm.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-05-25 08:39:26 -07:00
Linus Torvalds 3d762ca1cd Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs-2.6
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs-2.6:
  quota: Don't write quota info in dquot_commit()
  ext3: Fix writepage credits computation for ordered mode
2011-04-08 07:35:17 -07:00
Jan Kara b03f24567c quota: Don't write quota info in dquot_commit()
There's no reason to write quota info in dquot_commit(). The writing is a
relict from the old days when we didn't have dquot_acquire() and
dquot_release() and thus dquot_commit() could have created / removed quota
structures from the file. These days dquot_commit() only updates usage counters
/ limits in quota structure and thus there's no need to write quota info.

This also fixes an issue with journaling filesystem which didn't reserve
enough space in the transaction for write of quota info (it could have been
dirty at the time of dquot_commit() because of a race with other operation
changing it).

CC: stable@kernel.org
Reported-and-tested-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2011-04-01 00:23:46 +02:00
Lucas De Marchi 25985edced Fix common misspellings
Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2011-03-31 11:26:23 -03:00
Dave Chinner 55fa6091d8 fs: move i_sb_list out from under inode_lock
Protect the per-sb inode list with a new global lock
inode_sb_list_lock and use it to protect the list manipulations and
traversals. This lock replaces the inode_lock as the inodes on the
list can be validity checked while holding the inode->i_lock and
hence the inode_lock is no longer needed to protect the list.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-03-24 21:16:32 -04:00
Dave Chinner 250df6ed27 fs: protect inode->i_state with inode->i_lock
Protect inode state transitions and validity checks with the
inode->i_lock. This enables us to make inode state transitions
independently of the inode_lock and is the first step to peeling
away the inode_lock from the code.

This requires that __iget() is done atomically with i_state checks
during list traversals so that we don't race with another thread
marking the inode I_FREEING between the state check and grabbing the
reference.

Also remove the unlock_new_inode() memory barrier optimisation
required to avoid taking the inode_lock when clearing I_NEW.
Simplify the code by simply taking the inode->i_lock around the
state change and wakeup. Because the wakeup is no longer tricky,
remove the wake_up_inode() function and open code the wakeup where
necessary.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-03-24 21:16:31 -04:00
Jan Kara f00c9e44ad quota: Fix deadlock during path resolution
As Al Viro pointed out path resolution during Q_QUOTAON calls to quotactl
is prone to deadlocks. We hold s_umount semaphore for reading during the
path resolution and resolution itself may need to acquire the semaphore
for writing when e. g. autofs mountpoint is passed.

Solve the problem by performing the resolution before we get hold of the
superblock (and thus s_umount semaphore). The whole thing is complicated
by the fact that some filesystems (OCFS2) ignore the path argument. So to
distinguish between filesystem which want the path and which do not we
introduce new .quota_on_meta callback which does not get the path. OCFS2
then uses this callback instead of old .quota_on.

CC: Al Viro <viro@ZenIV.linux.org.uk>
CC: Christoph Hellwig <hch@lst.de>
CC: Ted Ts'o <tytso@mit.edu>
CC: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2011-01-12 19:14:55 +01:00
Joe Perches 055adcbd7d quota: Use %pV and __attribute__((format (printf in __quota_error and fix fallout
Use %pV in __quota_error so a single printk can not be
interleaved with other logging messages.
Add __attribute__((format (printf, 3, 4))) so format
and arguments can be verified by compiler.
Make sure printk formats and arguments match.

Block # needed a pointer dereference.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2011-01-10 19:04:05 +01:00
Jan Kara 4408ea41c0 quota: Fix possible oops in __dquot_initialize()
When quotaon(8) races with __dquot_initialize() or dqget() fails because
of EIO, ENOSPC, or similar error, we could possibly dereference NULL pointer
in inode->i_dquot[cnt]. Add proper checking.

Reported-by: Dmitry Monakhov <dmonakhov@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2010-10-28 01:30:06 +02:00
Jan Kara 86f3cbec4a quota: Fix issuing of warnings from dquot_transfer
__dquot_transfer accidentally called flush_warnings for a wrong set of
dquots which could result in quota warnings being issued with a wrong
identification. Also when operation fails because of EDQUOT, there's no
need check for issuing information message about user getting below limits
(no transfer has actually happened).

Signed-off-by: Jan Kara <jack@suse.cz>
2010-10-28 01:30:03 +02:00
Dmitry 9e32784b71 quota: fix dquot_disable vs dquot_transfer race v2
I've got following lockup:
dquot_disable                              dquot_transfer
                                            ->dqget()
					       sb_has_quota_active
dqopt->flags &= ~dquot_state_flag(f, cnt)      atomic_inc(dq->dq_count)
 ->drop_dquot_ref(sb, cnt);
    down_write(dqptr_sem)
    inode->i_dquot[cnt] = NULL              ->__dquot_transfer
invalidate_dquots(sb, cnt);		       down_write(&dqptr_sem)
  ->wait for dq_wait_unused		       inode->i_dquot = new_dquot
  /* wait forever */                            ^^^^New quota user^^^^^^

We cannot allow new references to dquots from inodes after drop_dquot_ref()
has removed them.  We have to recheck quota state under dqptr_sem and before
assignment, as we do it in dquot_initialize().

Signed-off-by: Dmitry Monakhov <dmonakhov@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2010-10-28 01:30:02 +02:00
Linus Torvalds 5f248c9c25 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: (96 commits)
  no need for list_for_each_entry_safe()/resetting with superblock list
  Fix sget() race with failing mount
  vfs: don't hold s_umount over close_bdev_exclusive() call
  sysv: do not mark superblock dirty on remount
  sysv: do not mark superblock dirty on mount
  btrfs: remove junk sb_dirt change
  BFS: clean up the superblock usage
  AFFS: wait for sb synchronization when needed
  AFFS: clean up dirty flag usage
  cifs: truncate fallout
  mbcache: fix shrinker function return value
  mbcache: Remove unused features
  add f_flags to struct statfs(64)
  pass a struct path to vfs_statfs
  update VFS documentation for method changes.
  All filesystems that need invalidate_inode_buffers() are doing that explicitly
  convert remaining ->clear_inode() to ->evict_inode()
  Make ->drop_inode() just return whether inode needs to be dropped
  fs/inode.c:clear_inode() is gone
  fs/inode.c:evict() doesn't care about delete vs. non-delete paths now
  ...

Fix up trivial conflicts in fs/nilfs2/super.c
2010-08-10 11:26:52 -07:00
Al Viro a4ffdde6e5 simplify checks for I_CLEAR/I_FREEING
add I_CLEAR instead of replacing I_FREEING with it.  I_CLEAR is
equivalent to I_FREEING for almost all code looking at either;
it's there to keep track of having called clear_inode() exactly
once per inode lifetime, at some point after having set I_FREEING.
I_CLEAR and I_FREEING never get set at the same time with the
current code, so we can switch to setting i_flags to I_FREEING | I_CLEAR
instead of I_CLEAR without loss of information.  As the result of
such change, checks become simpler and the amount of code that needs
to know about I_CLEAR shrinks a lot.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-08-09 16:47:44 -04:00
Linus Torvalds 90e0c22596 Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs-2.6
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs-2.6:
  ext3: Fix dirtying of journalled buffers in data=journal mode
  ext3: default to ordered mode
  quota: Use mark_inode_dirty_sync instead of mark_inode_dirty
  quota: Change quota error message to print out disk and function name
  MAINTAINERS: Update entries of ext2 and ext3
  MAINTAINERS: Update address of Andreas Dilger
  ext3: Avoid filesystem corruption after a crash under heavy delete load
  ext3: remove vestiges of nobh support
  ext3: Fix set but unused variables
  quota: clean up quota active checks
  quota: Clean up the namespace in dqblk_xfs.h
  quota: check quota reservation on remove_dquot_ref
2010-08-07 12:57:07 -07:00
Jan Kara 43d2932d88 quota: Use mark_inode_dirty_sync instead of mark_inode_dirty
Quota code never touches file data. It just modifies i_blocks + i_bytes
of inodes and inode flags of quota files. So use mark_inode_dirty_sync
instead of mark_inode_dirty.

Signed-off-by: Jan Kara <jack@suse.cz>
2010-07-23 12:50:46 +02:00
Jiaying Zhang fb5ffb0e16 quota: Change quota error message to print out disk and function name
The current quota error message doesn't always print the disk name, so
it is hard to identify the "bad" disk when quota error happens.

This patch changes the standardized quota error message to print out disk name
and function name. It also uses a combination of cpp macro and inline function
to provide better type checking and to lower the text size of the message.

[Jan Kara: Export __quota_error]

Signed-off-by: Jiaying Zhang <jiayingz@google.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2010-07-21 16:05:58 +02:00
Christoph Hellwig 189eef59e7 quota: clean up quota active checks
The various quota operations check for any quota beeing active on
a superblock, and the inode not having the noquota flag.

Merge these two checks into a dquot_active check and move that
into dquot.c as that's the only place where it's needed.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
2010-07-21 16:01:47 +02:00
Christoph Hellwig ade7ce31c2 quota: Clean up the namespace in dqblk_xfs.h
Almost all identifiers use the FS_* namespace, so rename the missing few
XFS_* ones to FS_* as well.  Without this some people might get upset
about having too many XFS names in generic code.

Acked-by: Steven Whitehouse <swhiteho@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
2010-07-21 16:01:46 +02:00
Dmitry Monakhov 7af9cce8ae quota: check quota reservation on remove_dquot_ref
Reserved space must being claimed before remove_dquot_ref() for a
given inode. Filesystem is responsible for performing force blocks
allocation in case of dealloc in ->quota_off. Let's add sanity check
for that case. Do it similar to add_dquot_ref().

Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Jan Kara <jack@suse.cz>
2010-07-21 16:01:46 +02:00
Dave Chinner 7f8275d0d6 mm: add context argument to shrinker callback
The current shrinker implementation requires the registered callback
to have global state to work from. This makes it difficult to shrink
caches that are not global (e.g. per-filesystem caches). Pass the shrinker
structure to the callback so that users can embed the shrinker structure
in the context the shrinker needs to operate on and get back to it in the
callback via container_of().

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
2010-07-19 14:56:17 +10:00
Linus Torvalds d28619f156 Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs-2.6
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs-2.6:
  quota: Convert quota statistics to generic percpu_counter
  ext3 uses rb_node = NULL; to zero rb_root.
  quota: Fixup dquot_transfer
  reiserfs: Fix resuming of quotas on remount read-write
  pohmelfs: Remove dead quota code
  ufs: Remove dead quota code
  udf: Remove dead quota code
  quota: rename default quotactl methods to dquot_
  quota: explicitly set ->dq_op and ->s_qcop
  quota: drop remount argument to ->quota_on and ->quota_off
  quota: move unmount handling into the filesystem
  quota: kill the vfs_dq_off and vfs_dq_quota_on_remount wrappers
  quota: move remount handling into the filesystem
  ocfs2: Fix use after free on remount read-only

Fix up conflicts in fs/ext4/super.c and fs/ufs/file.c
2010-05-30 09:11:11 -07:00
Linus Torvalds e4ce30f377 Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (40 commits)
  ext4: Make fsync sync new parent directories in no-journal mode
  ext4: Drop whitespace at end of lines
  ext4: Fix compat EXT4_IOC_ADD_GROUP
  ext4: Conditionally define compat ioctl numbers
  tracing: Convert more ext4 events to DEFINE_EVENT
  ext4: Add new tracepoints to track mballoc's buddy bitmap loads
  ext4: Add a missing trace hook
  ext4: restart ext4_ext_remove_space() after transaction restart
  ext4: Clear the EXT4_EOFBLOCKS_FL flag only when warranted
  ext4: Avoid crashing on NULL ptr dereference on a filesystem error
  ext4: Use bitops to read/modify i_flags in struct ext4_inode_info
  ext4: Convert calls of ext4_error() to EXT4_ERROR_INODE()
  ext4: Convert callers of ext4_get_blocks() to use ext4_map_blocks()
  ext4: Add new abstraction ext4_map_blocks() underneath ext4_get_blocks()
  ext4: Use our own write_cache_pages()
  ext4: Show journal_checksum option
  ext4: Fix for ext4_mb_collect_stats()
  ext4: check for a good block group before loading buddy pages
  ext4: Prevent creation of files larger than RLIMIT_FSIZE using fallocate
  ext4: Remove extraneous newlines in ext4_msg() calls
  ...

Fixed up trivial conflict in fs/ext4/fsync.c
2010-05-27 10:26:37 -07:00
Dmitry Monakhov f32764bd2b quota: Convert quota statistics to generic percpu_counter
Generic per-cpu counter has some memory overhead but it is negligible for
modern systems and embedded systems compile without quota support.  And code
reuse is a good thing. This patch should fix complain from preemptive kernels
which was introduced by dde9588853.

[Jan Kara: Fixed patch to work on 32-bit archs as well]

Reported-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Jan Kara <jack@suse.cz>
2010-05-27 18:56:27 +02:00
Jan Kara 4dea496974 quota: Fixup dquot_transfer
Commit bc8e5f0739 had a typo which caused
quota miscomputation when changing owner group of a file. Linus will hate
me.

Signed-off-by: Jan Kara <jack@suse.cz>
2010-05-27 17:39:36 +02:00
Christoph Hellwig 287a80958c quota: rename default quotactl methods to dquot_
Follow the dquot_* style used elsewhere in dquot.c.

[Jan Kara: Fixed up missing conversion of ext2]

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
2010-05-24 14:10:17 +02:00
Christoph Hellwig 123e9caf1e quota: explicitly set ->dq_op and ->s_qcop
Only set the quota operation vectors if the filesystem actually supports
quota instead of doing it for all filesystems in alloc_super().

[Jan Kara: Export dquot_operations and vfs_quotactl_ops]

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
2010-05-24 14:10:17 +02:00
Christoph Hellwig 307ae18a56 quota: drop remount argument to ->quota_on and ->quota_off
Remount handling has fully moved into the filesystem, so all this is
superflous now.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
2010-05-24 14:09:12 +02:00
Christoph Hellwig 0f0dd62fdd quota: kill the vfs_dq_off and vfs_dq_quota_on_remount wrappers
Instead of having wrappers in the VFS namespace export the dquot_suspend
and dquot_resume helpers directly.  Also rename vfs_quota_disable to
dquot_disable while we're at it.

[Jan Kara: Moved dquot_suspend to quotaops.h and made it inline]

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
2010-05-24 14:06:40 +02:00
Jan Kara bc8e5f0739 quota: Refactor dquot_transfer code so that OCFS2 can pass in its references
Currently, __dquot_transfer() acquires its own references of dquot structures
that will be put into inode. But for OCFS2, this creates a lock inversion
between dq_lock (waited on in dqget) and transaction start (started in
ocfs2_setattr). Currently, deadlock is impossible because dq_lock is acquired
only during dquot_acquire and dquot_release and we already hold a reference to
dquot structures in ocfs2_setattr so neither of these functions can be called
while we call dquot_transfer. But this is rather subtle and it is hard to teach
lockdep about it. So provide __dquot_transfer function that can be passed dquot
references directly. OCFS2 can then pass acquired dquot references directly to
__dquot_transfer with proper locking.

Signed-off-by: Jan Kara <jack@suse.cz>
2010-05-21 19:30:45 +02:00