Add annotation which lock protects which struct members to struct dquot
and struct mem_dqinfo.
Signed-off-by: Jan Kara <jack@suse.cz>

dq_data_lock is currently used to protect all modifications of quota
accounting information, consistency of quota accounting on the inode,
and dquot pointers from inode. As a result contention on the lock can be
pretty heavy.

Reduce the contention on the lock by protecting quota accounting
information by a new dquot->dq_dqb_lock and consistency of quota
accounting with inode usage by inode->i_lock.

This change reduces time to create 500000 files on ext4 on ramdisk by 50
different processes in separate directories by 6% when user quota is
turned on. When those 50 processes belong to 50 different users, the
improvement is about 9%.
Signed-off-by: Jan Kara <jack@suse.cz>

Provide helper __inode_get_bytes() which assumes i_lock is already
acquired. Quota code will need this to be able to use i_lock to protect
consistency of quota accounting information and inode usage.
Signed-off-by: Jan Kara <jack@suse.cz>

dquot_claim_reserved_space() and dquot_reclaim_reserved_space() have
only a single callsite. Inline them there.
Signed-off-by: Jan Kara <jack@suse.cz>

inode_incr_space() and inode_decr_space() have only two callsites.
Inline them there as that will make locking changes simpler.
Signed-off-by: Jan Kara <jack@suse.cz>

inode_add_rsv_space() and inode_sub_rsv_space() had only one callsite.
Inline them there directly. inode_claim_rsv_space() and
inode_reclaim_rsv_space() had two callsites so inline them there as
well. This will simplify further locking changes.
Signed-off-by: Jan Kara <jack@suse.cz>

When journalling quotas, we writeback all dquots immediately after
changing them as part of current transation. Thus there's no need to
write anything in dquot_writeback_dquots() and so we can avoid updating
list of dirty dquots to reduce dq_list_lock contention.

This change reduces time to create 500000 files on ext4 on ramdisk by 50
different processes in separate directories by 15% when user quota is
turned on.
Signed-off-by: Jan Kara <jack@suse.cz>

Filesystems that are journalling quotas generally don't need tracking of
dirty dquots in a list since forcing a transaction commit flushes all
quotas anyway. Allow filesystem to say it doesn't want dquots to be
tracked as it reduces contention on the dq_list_lock.
Signed-off-by: Jan Kara <jack@suse.cz>

Currently every dquot carries a wait_queue_head_t used only when we are
turning quotas off to wait for last users to drop dquot references.
Since such rare case is not performance sensitive in any means, just use
a global waitqueue for this and save space in struct dquot. Also convert
the logic to use wait_event() instead of open-coding it.
Signed-off-by: Jan Kara <jack@suse.cz>

Move locking of dq_list_lock into clear_dquot_dirty(). It makes the
function more self-contained and will simplify our life later.
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Jan Kara <jack@suse.cz>

Currently we mark dirty even dquots that are not active (i.e.,
initialization or reading failed for them). Thus later we have to check
whether dirty dquot is really active and just clear the dirty bit if
not. Avoid this complication by just never marking non-active dquot as
dirty.
Signed-off-by: Jan Kara <jack@suse.cz>

dqi_flags modifications are protected by dq_data_lock. However the
modifications in vfs_load_quota_inode() and in mark_info_dirty() were
not which could lead to corruption of dqi_flags. Since modifications to
dqi_flags are rare, this is hard to observe in practice but in theory it
could happen. Fix the problem by always using dq_data_lock for
protection.
Signed-off-by: Jan Kara <jack@suse.cz>

Currently we return -EIO on any error (or short read) from
->quota_read() while reading quota info. Propagate the error code
instead.
Suggested-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Jan Kara <jack@suse.cz>

v2_read_file_info() returned -1 instead of proper error codes on error.
Luckily this is not easily visible from userspace as we have called
->check_quota_file shortly before and thus already verified the quota
file is sane. Still set the error codes to proper values.
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Jan Kara <jack@suse.cz>

Push down acquisition of dqio_sem into ->read_file_info() callback. This
is for consistency with other operations and it also allows us to get
rid of an ugliness in OCFS2.
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Jan Kara <jack@suse.cz>

Push down acquisition of dqio_sem into ->write_file_info() callback.
Mostly for consistency with other operations.
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Jan Kara <jack@suse.cz>

Push down acquisition of dqio_sem into ->get_next_id() callback. Mostly
for consistency with other operations.
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Jan Kara <jack@suse.cz>

Push down acquisition of dqio_sem into ->release_dqblk() callback. It
will allow quota formats to decide whether they need it or not.
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Jan Kara <jack@suse.cz>

The old quota quota format has fixed offset in quota file based on ID so
there's no locking needed against concurrent modifications of the file
(locking against concurrent IO on the same dquot is still provided by
dq_lock).
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Jan Kara <jack@suse.cz>

When dquot has space already allocated in a quota file, we just
overwrite that place when writing dquot. So we don't need any protection
against other modifications of quota file as these keep dquot in place.
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Jan Kara <jack@suse.cz>

Push down acquisition of dqio_sem into ->write_dqblk() callback. It will
allow quota formats to decide whether they need it or not.
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Jan Kara <jack@suse.cz>

The old quota format has fixed offset in quota file based on ID so
there's no locking needed against concurrent modifications of the file
(locking against concurrent IO on the same dquot is still provided by
dq_lock).
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Jan Kara <jack@suse.cz>

Push down acquisition of dqio_sem into ->read_dqblk() callback. It will
allow quota formats to decide whether they need it or not.
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Jan Kara <jack@suse.cz>

Currently dquot writeout is only protected by dqio_sem held for writing.
As we transition to a finer grained locking we will use dquot->dq_lock
instead. So acquire it in dquot_commit() and move dqio_sem just around
->commit_dqblk() call as it is still needed to serialize quota file
changes.
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Jan Kara <jack@suse.cz>

vfs_load_quota_inode() needs dqio_sem only for reading. In fact dqio_sem
is not needed there at all since the function can be called only during
quota on when quota file cannot be modified but let's leave the
protection there since it is logical and the path is in no way
performance critical.
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Jan Kara <jack@suse.cz>

dquot_get_next_id() needs dqio_sem only for reading to protect against
racing with modification of quota file structure.
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Jan Kara <jack@suse.cz>

We need dqio_sem held just for reading when calling ->read_dqblk() in
dquot_acquire(). Also dqio_sem is not needed when setting DQ_READ_B and
DQ_ACTIVE_B as concurrent reads and dquot activations are serialized by
dq_lock. So acquire and release dqio_sem closer to the place where it is
needed. This reduces lock hold time and will make locking changes
easier.
Signed-off-by: Jan Kara <jack@suse.cz>

Convert dqio_mutex to rwsem and call it dqio_sem. No functional changes
yet.
Signed-off-by: Jan Kara <jack@suse.cz>

Pull x86 platform driver fix from Darren Hart:
 "Fix loop preventing some platforms from waking up via the power button
  in s2idle:

   - intel-vbtn: match power button on press rather than release"

* tag 'platform-drivers-x86-v4.13-4' of git://git.infradead.org/linux-platform-drivers-x86:
  platform/x86: intel-vbtn: match power button on press rather than release

Pull ext4 fixes from Ted Ts'o:
 "A large number of ext4 bug fixes and cleanups for v4.13"

* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: fix copy paste error in ext4_swap_extents()
  ext4: fix overflow caused by missing cast in ext4_resize_fs()
  ext4, project: expand inode extra size if possible
  ext4: cleanup ext4_expand_extra_isize_ea()
  ext4: restructure ext4_expand_extra_isize
  ext4: fix forgetten xattr lock protection in ext4_expand_extra_isize
  ext4: make xattr inode reads faster
  ext4: inplace xattr block update fails to deduplicate blocks
  ext4: remove unused mode parameter
  ext4: fix warning about stack corruption
  ext4: fix dir_nlink behaviour
  ext4: silence array overflow warning
  ext4: fix SEEK_HOLE/SEEK_DATA for blocksize < pagesize
  ext4: release discard bio after sending discard commands
  ext4: convert swap_inode_data() over to use swap() on most of the fields
  ext4: error should be cleared if ea_inode isn't added to the cache
  ext4: Don't clear SGID when inheriting ACLs
  ext4: preserve i_mode if __ext4_set_acl() fails
  ext4: remove unused metadata accounting variables
  ext4: correct comment references to ext4_ext_direct_IO()

Pull MIPS fixes from Ralf Baechle:
 "This fixes two build issues for ralink platforms, both due to missing
  #includes which used to be included indirectly via other headers"

* 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus:
  MIPS: ralink: mt7620: Add missing header
  MIPS: ralink: Fix build error due to missing header

The latest change of compat_sys_sigpending in commit 8f13621a
("sigpending(): move compat to native") has broken it in two ways.

First, it tries to write 4 bytes more than userspace expects:
sizeof(old_sigset_t) == sizeof(long) == 8 instead of
sizeof(compat_old_sigset_t) == sizeof(u32) == 4.

Second, on big endian architectures these bytes are being written in the
wrong order.

This bug was found by strace test suite.
Reported-by: Anatoly Pugachev <matorola@gmail.com>
Inspired-by: Eugene Syromyatnikov <evgsyr@gmail.com>
Fixes: 8f13621a ("sigpending(): move compat to native")
Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

This bug was found by a static code checker tool for copy paste
problems.
Signed-off-by: Maninder Singh <maninder1.s@samsung.com>
Signed-off-by: Vaneet Narang <v.narang@samsung.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

On a 32-bit platform, the value of n_blcoks_count may be wrong during
the file system is resized to size larger than 2^32 blocks.  This may
caused the superblock being corrupted with zero blocks count.

Fixes: 1c6bd717Signed-off-by: Jerry Lee <jerrylee@qnap.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org # 3.7+

When upgrading from old format, try to set project id
to old file first time, it will return EOVERFLOW, but if
that file is dirtied(touch etc), changing project id will
be allowed, this might be confusing for users, we could
try to expand @i_extra_isize here too.
Reported-by: Zhang Yi <yi.zhang@huawei.com>
Signed-off-by: Miao Xie <miaoxie@huawei.com>
Signed-off-by: Wang Shilong <wshilong@ddn.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

Clean up some goto statement, make ext4_expand_extra_isize_ea() clearer.
Signed-off-by: Miao Xie <miaoxie@huawei.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Wang Shilong <wshilong@ddn.com>

Current ext4_expand_extra_isize just tries to expand extra isize, if
someone is holding xattr lock or some check fails, it will give up.
So rename its name to ext4_try_to_expand_extra_isize.

Besides that, we clean up unnecessary check and move some relative checks
into it.
Signed-off-by: Miao Xie <miaoxie@huawei.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Wang Shilong <wshilong@ddn.com>

We should avoid the contention between the i_extra_isize update and
the inline data insertion, so move the xattr trylock in front of
i_extra_isize update.
Signed-off-by: Miao Xie <miaoxie@huawei.com>
Reviewed-by: Wang Shilong <wshilong@ddn.com>

ext4_xattr_inode_read() currently reads each block sequentially while
waiting for io operation to complete before moving on to the next
block. This prevents request merging in block layer.

Add a ext4_bread_batch() function that starts reads for all blocks
then optionally waits for them to complete. A similar logic is used
in ext4_find_entry(), so update that code to use the new function.
Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>