quota: Fix slow quotaoff

Eric has reported that commit dabc8b207566 ("quota: fix dqput() to
follow the guarantees dquot_srcu should provide") heavily increases
runtime of generic/270 xfstest for ext

quota: Fix slow quotaoff

Eric has reported that commit dabc8b207566 ("quota: fix dqput() to
follow the guarantees dquot_srcu should provide") heavily increases
runtime of generic/270 xfstest for ext4 in nojournal mode. The reason
for this is that ext4 in nojournal mode leaves dquots dirty until the last
dqput() and thus the cleanup done in quota_release_workfn() has to write
them all. Due to the way quota_release_workfn() is written this results
in synchronize_srcu() call for each dirty dquot which makes the dquot
cleanup when turning quotas off extremely slow.

To be able to avoid synchronize_srcu() for each dirty dquot we need to
rework how we track dquots to be cleaned up. Instead of keeping the last
dquot reference while it is on releasing_dquots list, we drop it right
away and mark the dquot with new DQ_RELEASING_B bit instead. This way we
can we can remove dquot from releasing_dquots list when new reference to
it is acquired and thus there's no need to call synchronize_srcu() each
time we drop dq_list_lock.

References: https://lore.kernel.org/all/ZRytn6CxFK2oECUt@debian-BULLSEYE-live-builder-AMD64
Reported-by: Eric Whitney <enwlinux@gmail.com>
Fixes: dabc8b207566 ("quota: fix dqput() to follow the guarantees dquot_srcu should provide")
CC: stable@vger.kernel.org
Signed-off-by: Jan Kara <jack@suse.cz>

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quota: cleanup double word in comment

Remove the second 'handle'.

Link: https://lore.kernel.org/r/20220116125936.389767-1-trix@redhat.com
Signed-off-by: Tom Rix <trix@redhat.com>
Signed-off-by: Jan

quota: cleanup double word in comment

Remove the second 'handle'.

Link: https://lore.kernel.org/r/20220116125936.389767-1-trix@redhat.com
Signed-off-by: Tom Rix <trix@redhat.com>
Signed-off-by: Jan Kara <jack@suse.cz>

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fs/quota: update quota state flags scheme with project quota flags

Current quota state flags scheme doesn't include project quota and thus
shows all flags after DQUOT_USAGE_ENABLED wrong. Fix this a

fs/quota: update quota state flags scheme with project quota flags

Current quota state flags scheme doesn't include project quota and thus
shows all flags after DQUOT_USAGE_ENABLED wrong. Fix this and also add
DQUOT_NOLIST_DIRTY to the scheme.

Link: https://lore.kernel.org/r/1602989814-28922-1-git-send-email-dotdot@yandex-team.ru
Signed-off-by: Roman Anufriev <dotdot@yandex-team.ru>
Signed-off-by: Jan Kara <jack@suse.cz>

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fs/quota: handle overflows of sysctl fs.quota.* and report as unsigned long

Quota statistics counted as 64-bit per-cpu counter. Reading sums per-cpu
fractions as signed 64-bit int, filters negative

fs/quota: handle overflows of sysctl fs.quota.* and report as unsigned long

Quota statistics counted as 64-bit per-cpu counter. Reading sums per-cpu
fractions as signed 64-bit int, filters negative values and then reports
lower half as signed 32-bit int.

Result may looks like:

fs.quota.allocated_dquots = 22327
fs.quota.cache_hits = -489852115
fs.quota.drops = -487288718
fs.quota.free_dquots = 22083
fs.quota.lookups = -486883485
fs.quota.reads = 22327
fs.quota.syncs = 335064
fs.quota.writes = 3088689

Values bigger than 2^31-1 reported as negative.

All counters except "allocated_dquots" and "free_dquots" are monotonic,
thus they should be reported as is without filtering negative values.

Kernel doesn't have generic helper for 64-bit sysctl yet,
let's use at least unsigned long.

Link: https://lore.kernel.org/r/157337934693.2078.9842146413181153727.stgit@buzz
Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: Jan Kara <jack@suse.cz>

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fs/quota: Replace XQM_MAXQUOTAS usage with MAXQUOTAS

XQM_MAXQUOTAS and MAXQUOTAS are, it appears, equivalent. Replace all
usage of XQM_MAXQUOTAS and remove it along with the unused XQM_*QUOTA
defini

fs/quota: Replace XQM_MAXQUOTAS usage with MAXQUOTAS

XQM_MAXQUOTAS and MAXQUOTAS are, it appears, equivalent. Replace all
usage of XQM_MAXQUOTAS and remove it along with the unused XQM_*QUOTA
definitions.

Signed-off-by: Jeremy Cline <jcline@redhat.com>
Signed-off-by: Jan Kara <jack@suse.cz>

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quota: Kill an unused extern entry form quota.h

Kill an unused extern entry from quota.h
which is leftover of below patch.

[f32764bd2: quota: Convert quota statistics to generic percpu_counter]

Si

quota: Kill an unused extern entry form quota.h

Kill an unused extern entry from quota.h
which is leftover of below patch.

[f32764bd2: quota: Convert quota statistics to generic percpu_counter]

Signed-off-by: Ritesh Harjani <riteshh@codeaurora.org>
Signed-off-by: Jan Kara <jack@suse.cz>

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quota: Add lock annotations to struct members

Add annotation which lock protects which struct members to struct dquot
and struct mem_dqinfo.

Signed-off-by: Jan Kara <jack@suse.cz>

quota: Reduce contention on dq_data_lock

dq_data_lock is currently used to protect all modifications of quota
accounting information, consistency of quota accounting on the inode,
and dquot pointers

quota: Reduce contention on dq_data_lock

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>

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quota: Allow disabling tracking of dirty dquots in a list

Filesystems that are journalling quotas generally don't need tracking of
dirty dquots in a list since forcing a transaction commit flushes a

quota: Allow disabling tracking of dirty dquots in a list

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>

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quota: Remove dq_wait_unused from dquot

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 ca

quota: Remove dq_wait_unused from dquot

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>

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quota: Convert dqio_mutex to rwsem

Convert dqio_mutex to rwsem and call it dqio_sem. No functional changes
yet.

Signed-off-by: Jan Kara <jack@suse.cz>

quota: add get_inode_usage callback to transfer multi-inode charges

Ext4 ea_inode feature allows storing xattr values in external inodes to
be able to store values that are bigger than a block in si

quota: add get_inode_usage callback to transfer multi-inode charges

Ext4 ea_inode feature allows storing xattr values in external inodes to
be able to store values that are bigger than a block in size. Ext4 also
has deduplication support for these type of inodes. With deduplication,
the actual storage waste is eliminated but the users of such inodes are
still charged full quota for the inodes as if there was no sharing
happening in the background.

This design requires ext4 to manually charge the users because the
inodes are shared.

An implication of this is that, if someone calls chown on a file that
has such references we need to transfer the quota for the file and xattr
inodes. Current dquot_transfer() function implicitly transfers one inode
charge. With ea_inode feature, we would like to transfer multiple inode
charges.

Add get_inode_usage callback which can interrogate the total number of
inodes that were charged for a given inode.

[ Applied fix from Colin King to make sure the 'ret' variable is
initialized on the successful return path. Detected by
CoverityScan, CID#1446616 ("Uninitialized scalar variable") --tytso]

Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Jan Kara <jack@suse.cz>

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quota: constify struct path in quota_on

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

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.

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>

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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 q

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>

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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

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>

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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 an

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>

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quota: add new quotactl Q_XGETNEXTQUOTA

Q_XGETNEXTQUOTA is exactly like Q_XGETQUOTA, except that it
will return quota information for the id equal to or greater
than the id requested. In other word

quota: add new quotactl Q_XGETNEXTQUOTA

Q_XGETNEXTQUOTA is exactly like Q_XGETQUOTA, except that it
will return quota information for the id equal to or greater
than the id requested. In other words, if the requested id has
no quota, the command will return quota information for the
next higher id which does have a quota set. If no higher id
has an active quota, -ESRCH is returned.

This allows filesystems to do efficient iteration in kernelspace,
much like extN filesystems do in userspace when asked to report
all active quotas.

The patch adds a d_id field to struct qc_dqblk so that we can
pass back the id of the quota which was found, and return it
to userspace.

Today, filesystems such as XFS require getpwent-style iterations,
and for systems which have i.e. LDAP backends, this can be very
slow, or even impossible if iteration is not allowed in the
configuration.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Dave Chinner <david@fromorbit.com>

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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_opera

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>

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quota: reorder flags in quota state

Flags in struct quota_state keep flags for each quota type and
some common flags. This patch reorders typed flags:

Before:

0 USRQUOTA DQUOT_USAGE_ENABLED
1 USRQ

quota: reorder flags in quota state

Flags in struct quota_state keep flags for each quota type and
some common flags. This patch reorders typed flags:

Before:

0 USRQUOTA DQUOT_USAGE_ENABLED
1 USRQUOTA DQUOT_LIMITS_ENABLED
2 USRQUOTA DQUOT_SUSPENDED
3 GRPQUOTA DQUOT_USAGE_ENABLED
4 GRPQUOTA DQUOT_LIMITS_ENABLED
5 GRPQUOTA DQUOT_SUSPENDED
6 DQUOT_QUOTA_SYS_FILE
7 DQUOT_NEGATIVE_USAGE

After:

0 USRQUOTA DQUOT_USAGE_ENABLED
1 GRPQUOTA DQUOT_USAGE_ENABLED
2 USRQUOTA DQUOT_LIMITS_ENABLED
3 GRPQUOTA DQUOT_LIMITS_ENABLED
4 USRQUOTA DQUOT_SUSPENDED
5 GRPQUOTA DQUOT_SUSPENDED
6 DQUOT_QUOTA_SYS_FILE
7 DQUOT_NEGATIVE_USAGE

Now we can get bitmap of all enabled/suspended quota types without loop.
For example suspended: (flags / DQUOT_SUSPENDED) & ((1 << MAXQUOTAS) - 1).

add/remove: 0/1 grow/shrink: 3/11 up/down: 56/-215 (-159)
function old new delta
__dquot_initialize 423 447 +24
dquot_transfer 181 197 +16
dquot_alloc_inode 286 302 +16
dquot_reclaim_space_nodirty 316 313 -3
dquot_claim_space_nodirty 314 311 -3
dquot_resume 286 281 -5
dquot_free_inode 332 324 -8
__dquot_alloc_space 500 492 -8
dquot_disable 1944 1929 -15
dquot_quota_enable 252 236 -16
__dquot_free_space 750 734 -16
dquot_writeback_dquots 625 608 -17
__dquot_transfer 1186 1154 -32
dquot_quota_sync 299 261 -38
dquot_active.isra 54 - -54

Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: Jan Kara <jack@suse.cz>

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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_S

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>

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quota: Remove ->get_xstate and ->get_xstatev callbacks

These callbacks are now unused. Remove them.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>

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.

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>

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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 maxi

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>

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quota: Remove quota_on_meta callback

There are no more users for quota_on_meta callback. Just remove it.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>