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Author SHA1 Message Date
Jan Kara e2926630f6 quota: Don't overflow quota file offsets
[ Upstream commit 10f04d40a9 ]

The on-disk quota format supports quota files with upto 2^32 blocks. Be
careful when computing quota file offsets in the quota files from block
numbers as they can overflow 32-bit types. Since quota files larger than
4GB would require ~26 millions of quota users, this is mostly a
theoretical concern now but better be careful, fuzzers would find the
problem sooner or later anyway...

Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-01-06 14:48:39 +01:00
Jan Kara 0118204534 quota: Sanity-check quota file headers on load
commit 11c514a99b upstream.

Perform basic sanity checks of quota headers to avoid kernel crashes on
corrupted quota files.

CC: stable@vger.kernel.org
Reported-by: syzbot+f816042a7ae2225f25ba@syzkaller.appspotmail.com
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-12-30 11:51:00 +01:00
Eric Dumazet b7e2b1fe04 quota: clear padding in v2r1_mem2diskdqb()
[ Upstream commit 3d3dc274ce ]

Freshly allocated memory contains garbage, better make sure
to init all struct v2r1_disk_dqblk fields to avoid KMSAN report:

BUG: KMSAN: uninit-value in qtree_entry_unused+0x137/0x1b0 fs/quota/quota_tree.c:218
CPU: 0 PID: 23373 Comm: syz-executor.1 Not tainted 5.9.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x21c/0x280 lib/dump_stack.c:118
 kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:122
 __msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:219
 qtree_entry_unused+0x137/0x1b0 fs/quota/quota_tree.c:218
 v2r1_mem2diskdqb+0x43d/0x710 fs/quota/quota_v2.c:285
 qtree_write_dquot+0x226/0x870 fs/quota/quota_tree.c:394
 v2_write_dquot+0x1ad/0x280 fs/quota/quota_v2.c:333
 dquot_commit+0x4af/0x600 fs/quota/dquot.c:482
 ext4_write_dquot fs/ext4/super.c:5934 [inline]
 ext4_mark_dquot_dirty+0x4d8/0x6a0 fs/ext4/super.c:5985
 mark_dquot_dirty fs/quota/dquot.c:347 [inline]
 mark_all_dquot_dirty fs/quota/dquot.c:385 [inline]
 dquot_alloc_inode+0xc05/0x12b0 fs/quota/dquot.c:1755
 __ext4_new_inode+0x8204/0x9d70 fs/ext4/ialloc.c:1155
 ext4_tmpfile+0x41a/0x850 fs/ext4/namei.c:2686
 vfs_tmpfile+0x2a2/0x570 fs/namei.c:3283
 do_tmpfile fs/namei.c:3316 [inline]
 path_openat+0x4035/0x6a90 fs/namei.c:3359
 do_filp_open+0x2b8/0x710 fs/namei.c:3395
 do_sys_openat2+0xa88/0x1140 fs/open.c:1168
 do_sys_open fs/open.c:1184 [inline]
 __do_compat_sys_openat fs/open.c:1242 [inline]
 __se_compat_sys_openat+0x2a4/0x310 fs/open.c:1240
 __ia32_compat_sys_openat+0x56/0x70 fs/open.c:1240
 do_syscall_32_irqs_on arch/x86/entry/common.c:80 [inline]
 __do_fast_syscall_32+0x129/0x180 arch/x86/entry/common.c:139
 do_fast_syscall_32+0x6a/0xc0 arch/x86/entry/common.c:162
 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:205
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c
RIP: 0023:0xf7ff4549
Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 eb 0d 90 90 90 90 90 90 90 90 90 90 90 90
RSP: 002b:00000000f55cd0cc EFLAGS: 00000296 ORIG_RAX: 0000000000000127
RAX: ffffffffffffffda RBX: 00000000ffffff9c RCX: 0000000020000000
RDX: 0000000000410481 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:143 [inline]
 kmsan_internal_poison_shadow+0x66/0xd0 mm/kmsan/kmsan.c:126
 kmsan_slab_alloc+0x8a/0xe0 mm/kmsan/kmsan_hooks.c:80
 slab_alloc_node mm/slub.c:2907 [inline]
 slab_alloc mm/slub.c:2916 [inline]
 __kmalloc+0x2bb/0x4b0 mm/slub.c:3982
 kmalloc include/linux/slab.h:559 [inline]
 getdqbuf+0x56/0x150 fs/quota/quota_tree.c:52
 qtree_write_dquot+0xf2/0x870 fs/quota/quota_tree.c:378
 v2_write_dquot+0x1ad/0x280 fs/quota/quota_v2.c:333
 dquot_commit+0x4af/0x600 fs/quota/dquot.c:482
 ext4_write_dquot fs/ext4/super.c:5934 [inline]
 ext4_mark_dquot_dirty+0x4d8/0x6a0 fs/ext4/super.c:5985
 mark_dquot_dirty fs/quota/dquot.c:347 [inline]
 mark_all_dquot_dirty fs/quota/dquot.c:385 [inline]
 dquot_alloc_inode+0xc05/0x12b0 fs/quota/dquot.c:1755
 __ext4_new_inode+0x8204/0x9d70 fs/ext4/ialloc.c:1155
 ext4_tmpfile+0x41a/0x850 fs/ext4/namei.c:2686
 vfs_tmpfile+0x2a2/0x570 fs/namei.c:3283
 do_tmpfile fs/namei.c:3316 [inline]
 path_openat+0x4035/0x6a90 fs/namei.c:3359
 do_filp_open+0x2b8/0x710 fs/namei.c:3395
 do_sys_openat2+0xa88/0x1140 fs/open.c:1168
 do_sys_open fs/open.c:1184 [inline]
 __do_compat_sys_openat fs/open.c:1242 [inline]
 __se_compat_sys_openat+0x2a4/0x310 fs/open.c:1240
 __ia32_compat_sys_openat+0x56/0x70 fs/open.c:1240
 do_syscall_32_irqs_on arch/x86/entry/common.c:80 [inline]
 __do_fast_syscall_32+0x129/0x180 arch/x86/entry/common.c:139
 do_fast_syscall_32+0x6a/0xc0 arch/x86/entry/common.c:162
 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:205
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c

Fixes: 498c60153e ("quota: Implement quota format with 64-bit space and inode limits")
Link: https://lore.kernel.org/r/20200924183619.4176790-1-edumazet@google.com
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Jan Kara <jack@suse.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-10-29 09:57:42 +01:00
Eric Sandeen 16b730a459 fs: avoid softlockups in s_inodes iterators
[ Upstream commit 04646aebd3 ]

Anything that walks all inodes on sb->s_inodes list without rescheduling
risks softlockups.

Previous efforts were made in 2 functions, see:

c27d82f fs/drop_caches.c: avoid softlockups in drop_pagecache_sb()
ac05fbb inode: don't softlockup when evicting inodes

but there hasn't been an audit of all walkers, so do that now.  This
also consistently moves the cond_resched() calls to the bottom of each
loop in cases where it already exists.

One loop remains: remove_dquot_ref(), because I'm not quite sure how
to deal with that one w/o taking the i_lock.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-01-12 12:21:37 +01:00
Konstantin Khlebnikov 19f612e6cc fs/quota: handle overflows of sysctl fs.quota.* and report as unsigned long
[ Upstream commit 6fcbcec9cf ]

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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-01-04 19:17:25 +01:00
Dmitry Monakhov 1a44370765 quota: fix livelock in dquot_writeback_dquots
commit 6ff33d99fc upstream.

Write only quotas which are dirty at entry.

XFSTEST: b10ad23566

Link: https://lore.kernel.org/r/20191031103920.3919-1-dmonakhov@openvz.org
CC: stable@vger.kernel.org
Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: Dmitry Monakhov <dmtrmonakhov@yandex-team.ru>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-12-17 19:56:43 +01:00
Dmitry Monakhov b28df8395d quota: Check that quota is not dirty before release
commit df4bb5d128 upstream.

There is a race window where quota was redirted once we drop dq_list_lock inside dqput(),
but before we grab dquot->dq_lock inside dquot_release()

TASK1                                                       TASK2 (chowner)
->dqput()
  we_slept:
    spin_lock(&dq_list_lock)
    if (dquot_dirty(dquot)) {
          spin_unlock(&dq_list_lock);
          dquot->dq_sb->dq_op->write_dquot(dquot);
          goto we_slept
    if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) {
          spin_unlock(&dq_list_lock);
          dquot->dq_sb->dq_op->release_dquot(dquot);
                                                            dqget()
							    mark_dquot_dirty()
							    dqput()
          goto we_slept;
        }
So dquot dirty quota will be released by TASK1, but on next we_sleept loop
we detect this and call ->write_dquot() for it.
XFSTEST: 440a80d4cb

Link: https://lore.kernel.org/r/20191031103920.3919-2-dmonakhov@openvz.org
CC: stable@vger.kernel.org
Signed-off-by: Dmitry Monakhov <dmtrmonakhov@yandex-team.ru>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-12-17 19:56:43 +01:00
Chengguang Xu 4b8e1106dd quota: fix condition for resetting time limit in do_set_dqblk()
We reset time limit when current usage is smaller
or equal to soft limit in other place, so follow
this rule in do_set_dqblk().

Signed-off-by: Chengguang Xu <cgxu519@zoho.com.cn>
Link: https://lore.kernel.org/r/20190724053216.19392-1-cgxu519@zoho.com.cn
Signed-off-by: Jan Kara <jack@suse.cz>
2019-07-31 12:04:42 +02:00
Linus Torvalds 682f7c5c46 \n
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Merge tag 'for_v5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs

Pull ext2, udf and quota updates from Jan Kara:

 - some ext2 fixes and cleanups

 - a fix of udf bug when extending files

 - a fix of quota Q_XGETQSTAT[V] handling

* tag 'for_v5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
  udf: Fix incorrect final NOT_ALLOCATED (hole) extent length
  ext2: Use kmemdup rather than duplicating its implementation
  quota: honor quota type in Q_XGETQSTAT[V] calls
  ext2: Always brelse bh on failure in ext2_iget()
  ext2: add missing brelse() in ext2_iget()
  ext2: Fix a typo in ext2_getattr argument
  ext2: fix a typo in comment
  ext2: add missing brelse() in ext2_new_inode()
  ext2: optimize ext2_xattr_get()
  ext2: introduce new helper for xattr entry comparison
  ext2: merge xattr next entry check to ext2_xattr_entry_valid()
  ext2: code cleanup for ext2_preread_inode()
  ext2: code cleanup by using test_opt() and clear_opt()
  doc: ext2: update description of quota options for ext2
  ext2: Strengthen xattr block checks
  ext2: Merge loops in ext2_xattr_set()
  ext2: introduce helper for xattr entry validation
  ext2: introduce helper for xattr header validation
  quota: add dqi_dirty_list description to comment of Dquot List Management
2019-07-10 20:27:07 -07:00
Eric Sandeen 555b2c3da1 quota: honor quota type in Q_XGETQSTAT[V] calls
The code in quota_getstate and quota_getstatev is strange; it
says the returned fs_quota_stat[v] structure has room for only
one type of time limits, so fills it in with the first enabled
quota, even though every quotactl command must have a type sent
in by the user.

Instead of just picking the first enabled quota, fill in the
reply with the timers for the quota type that was actually
requested.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2019-06-25 17:51:35 +02:00
yangerkun c6d9c35d16 quota: fix a problem about transfer quota
Run below script as root, dquot_add_space will return -EDQUOT since
__dquot_transfer call dquot_add_space with flags=0, and dquot_add_space
think it's a preallocation. Fix it by set flags as DQUOT_SPACE_WARN.

mkfs.ext4 -O quota,project /dev/vdb
mount -o prjquota /dev/vdb /mnt
setquota -P 23 1 1 0 0 /dev/vdb
dd if=/dev/zero of=/mnt/test-file bs=4K count=1
chattr -p 23 test-file

Fixes: 7b9ca4c61b ("quota: Reduce contention on dq_data_lock")
Signed-off-by: yangerkun <yangerkun@huawei.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2019-06-19 15:25:41 +02:00
Thomas Gleixner ec8f24b7fa treewide: Add SPDX license identifier - Makefile/Kconfig
Add SPDX license identifiers to all Make/Kconfig files which:

 - Have no license information of any form

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 10:50:46 +02:00
Thomas Gleixner 09c434b8a0 treewide: Add SPDX license identifier for more missed files
Add SPDX license identifiers to all files which:

 - Have no license information of any form

 - Have MODULE_LICENCE("GPL*") inside which was used in the initial
   scan/conversion to ignore the file

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 10:50:45 +02:00
Chengguang Xu f44840ad1f quota: add dqi_dirty_list description to comment of Dquot List Management
Actually there are four lists for dquot management, so add
the description of dqui_dirty_list to comment.

Signed-off-by: Chengguang Xu <cgxu519@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2019-05-20 10:50:48 +02:00
Chengguang Xu 632a9f3acd quota: check time limit when back out space/inode change
When we fail from allocating inode/space, we back out
the change we already did. In a special case which has
exceeded soft limit by the change, we should also check
time limit and reset it properly.

Signed-off-by: Chengguang Xu <cgxu519@gmx.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2019-04-30 18:05:55 +02:00
Jiang Biao 78bc3334a6 fs/quota: erase unused but set variable warning
Local variable *reserved* of remove_dquot_ref() is only used if
define CONFIG_QUOTA_DEBUG, but not ebraced in CONFIG_QUOTA_DEBUG
macro, which leads to unused-but-set-variable warning when compiling.

This patch ebrace it into CONFIG_QUOTA_DEBUG macro like what is done
in add_dquot_ref().

Signed-off-by: Jiang Biao <benbjiang@tencent.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2019-04-25 17:04:43 +02:00
Chengguang Xu 3ef177ec9d quota: fix wrong indentation
We need to check return code only when calling ->read_dqblk(),
so fix it properly.

Signed-off-by: Chengguang Xu <cgxu519@gmx.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2019-04-25 11:59:35 +02:00
Sascha Hauer 27942ef503 quota: remove trailing whitespaces
This removes all trailing whitespaces in fs/quota/.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Jan Kara <jack@suse.cz>
2019-03-26 11:21:37 +01:00
Chengguang Xu df15a2a59d quota: code cleanup for __dquot_alloc_space()
Replace (flags & DQUOT_SPACE_RESERVE) with
variable reserve.

Signed-off-by: Chengguang Xu <cgxu519@gmx.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2019-03-26 11:21:23 +01:00
Javier Barrio 41c4f85cda quota: Lock s_umount in exclusive mode for Q_XQUOTA{ON,OFF} quotactls.
Commit 1fa5efe362 (ext4: Use generic helpers for quotaon
and quotaoff) made possible to call quotactl(Q_XQUOTAON/OFF) on ext4 filesystems
with sysfile quota support. This leads to calling dquot_enable/disable without s_umount
held in excl. mode, because quotactl_cmd_onoff checks only for Q_QUOTAON/OFF.

The following WARN_ON_ONCE triggers (in this case for dquot_enable, ext4, latest Linus' tree):

[  117.807056] EXT4-fs (dm-0): mounted filesystem with ordered data mode. Opts: quota,prjquota

[...]

[  155.036847] WARNING: CPU: 0 PID: 2343 at fs/quota/dquot.c:2469 dquot_enable+0x34/0xb9
[  155.036851] Modules linked in: quota_v2 quota_tree ipv6 af_packet joydev mousedev psmouse serio_raw pcspkr i2c_piix4 intel_agp intel_gtt e1000 ttm drm_kms_helper drm agpgart fb_sys_fops syscopyarea sysfillrect sysimgblt i2c_core input_leds kvm_intel kvm irqbypass qemu_fw_cfg floppy evdev parport_pc parport button crc32c_generic dm_mod ata_generic pata_acpi ata_piix libata loop ext4 crc16 mbcache jbd2 usb_storage usbcore sd_mod scsi_mod
[  155.036901] CPU: 0 PID: 2343 Comm: qctl Not tainted 4.20.0-rc6-00025-gf5d582777bcb #9
[  155.036903] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014
[  155.036911] RIP: 0010:dquot_enable+0x34/0xb9
[  155.036915] Code: 41 56 41 55 41 54 55 53 4c 8b 6f 28 74 02 0f 0b 4d 8d 7d 70 49 89 fc 89 cb 41 89 d6 89 f5 4c 89 ff e8 23 09 ea ff 85 c0 74 0a <0f> 0b 4c 89 ff e8 8b 09 ea ff 85 db 74 6a 41 8b b5 f8 00 00 00 0f
[  155.036918] RSP: 0018:ffffb09b00493e08 EFLAGS: 00010202
[  155.036922] RAX: 0000000000000001 RBX: 0000000000000008 RCX: 0000000000000008
[  155.036924] RDX: 0000000000000001 RSI: 0000000000000002 RDI: ffff9781b67cd870
[  155.036926] RBP: 0000000000000002 R08: 0000000000000000 R09: 61c8864680b583eb
[  155.036929] R10: ffffb09b00493e48 R11: ffffffffff7ce7d4 R12: ffff9781b7ee8d78
[  155.036932] R13: ffff9781b67cd800 R14: 0000000000000004 R15: ffff9781b67cd870
[  155.036936] FS:  00007fd813250b88(0000) GS:ffff9781ba000000(0000) knlGS:0000000000000000
[  155.036939] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  155.036942] CR2: 00007fd812ff61d6 CR3: 000000007c882000 CR4: 00000000000006b0
[  155.036951] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  155.036953] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  155.036955] Call Trace:
[  155.037004]  dquot_quota_enable+0x8b/0xd0
[  155.037011]  kernel_quotactl+0x628/0x74e
[  155.037027]  ? do_mprotect_pkey+0x2a6/0x2cd
[  155.037034]  __x64_sys_quotactl+0x1a/0x1d
[  155.037041]  do_syscall_64+0x55/0xe4
[  155.037078]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[  155.037105] RIP: 0033:0x7fd812fe1198
[  155.037109] Code: 02 77 0d 48 89 c1 48 c1 e9 3f 75 04 48 8b 04 24 48 83 c4 50 5b c3 48 83 ec 08 49 89 ca 48 63 d2 48 63 ff b8 b3 00 00 00 0f 05 <48> 89 c7 e8 c1 eb ff ff 5a c3 48 63 ff b8 bb 00 00 00 0f 05 48 89
[  155.037112] RSP: 002b:00007ffe8cd7b050 EFLAGS: 00000206 ORIG_RAX: 00000000000000b3
[  155.037116] RAX: ffffffffffffffda RBX: 00007ffe8cd7b148 RCX: 00007fd812fe1198
[  155.037119] RDX: 0000000000000000 RSI: 00007ffe8cd7cea9 RDI: 0000000000580102
[  155.037121] RBP: 00007ffe8cd7b0f0 R08: 000055fc8eba8a9d R09: 0000000000000000
[  155.037124] R10: 00007ffe8cd7b074 R11: 0000000000000206 R12: 00007ffe8cd7b168
[  155.037126] R13: 000055fc8eba8897 R14: 0000000000000000 R15: 0000000000000000
[  155.037131] ---[ end trace 210f864257175c51 ]---

and then the syscall proceeds without s_umount locking.

This patch locks the superblock ->s_umount sem. in exclusive mode for all Q_XQUOTAON/OFF
quotactls too in addition to Q_QUOTAON/OFF.

AFAICT, other than ext4, only xfs and ocfs2 are affected by this change.
The VFS will now call in xfs_quota_* functions with s_umount held, which wasn't the case
before. This looks good to me but I can not say for sure. Ext4 and ocfs2 where already
beeing called with s_umount exclusive via quota_quotaon/off which is basically the same.

Signed-off-by: Javier Barrio <javier.barrio.mart@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2018-12-18 18:29:15 +01:00
Jeremy Cline 7b6924d94a fs/quota: Fix spectre gadget in do_quotactl
'type' is user-controlled, so sanitize it after the bounds check to
avoid using it in speculative execution. This covers the following
potential gadgets detected with the help of smatch:

* fs/ext4/super.c:5741 ext4_quota_read() warn: potential spectre issue
  'sb_dqopt(sb)->files' [r]
* fs/ext4/super.c:5778 ext4_quota_write() warn: potential spectre issue
  'sb_dqopt(sb)->files' [r]
* fs/f2fs/super.c:1552 f2fs_quota_read() warn: potential spectre issue
  'sb_dqopt(sb)->files' [r]
* fs/f2fs/super.c:1608 f2fs_quota_write() warn: potential spectre issue
  'sb_dqopt(sb)->files' [r]
* fs/quota/dquot.c:412 mark_info_dirty() warn: potential spectre issue
  'sb_dqopt(sb)->info' [w]
* fs/quota/dquot.c:933 dqinit_needed() warn: potential spectre issue
  'dquots' [r]
* fs/quota/dquot.c:2112 dquot_commit_info() warn: potential spectre
  issue 'dqopt->ops' [r]
* fs/quota/dquot.c:2362 vfs_load_quota_inode() warn: potential spectre
  issue 'dqopt->files' [w] (local cap)
* fs/quota/dquot.c:2369 vfs_load_quota_inode() warn: potential spectre
  issue 'dqopt->ops' [w] (local cap)
* fs/quota/dquot.c:2370 vfs_load_quota_inode() warn: potential spectre
  issue 'dqopt->info' [w] (local cap)
* fs/quota/quota.c:110 quota_getfmt() warn: potential spectre issue
  'sb_dqopt(sb)->info' [r]
* fs/quota/quota_v2.c:84 v2_check_quota_file() warn: potential spectre
  issue 'quota_magics' [w]
* fs/quota/quota_v2.c:85 v2_check_quota_file() warn: potential spectre
  issue 'quota_versions' [w]
* fs/quota/quota_v2.c:96 v2_read_file_info() warn: potential spectre
  issue 'dqopt->info' [r]
* fs/quota/quota_v2.c:172 v2_write_file_info() warn: potential spectre
  issue 'dqopt->info' [r]

Additionally, a quick inspection indicates there are array accesses with
'type' in quota_on() and quota_off() functions which are also addressed
by this.

Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Jeremy Cline <jcline@redhat.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2018-08-22 18:17:48 +02:00
Jeremy Cline 64d9d13828 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>
2018-08-22 18:17:29 +02:00
Jan Kara 1822193b5d quota: Cleanup list iteration in dqcache_shrink_scan()
Use list_first_entry() and list_empty() instead of opencoded variants.

Reviewed-by: Matthew Wilcox <mawilcox@microsoft.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2018-06-20 11:04:26 +02:00
Greg Thelen 9560ba306d quota: reclaim least recently used dquots
The dquots in the free_dquots list are not reclaimed in LRU way.
put_dquot_last() puts entries to the tail and dqcache_shrink_scan()
frees from the tail. Free unreferenced dquots in LRU order because it
seems more reasonable than freeing most recently used.

Signed-off-by: Greg Thelen <gthelen@google.com>
Signed-off-by: Shakeel Butt <shakeelb@google.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2018-06-20 11:04:26 +02:00
Jia-Ju Bai 1aa3b3e0cb fs: quota: Replace GFP_ATOMIC with GFP_KERNEL in dquot_init
dquot_init() is never called in atomic context.
This function is only set as a parameter of fs_initcall().

Despite never getting called from atomic context,
dquot_init() calls __get_free_pages() with GFP_ATOMIC,
which waits busily for allocation.
GFP_ATOMIC is not necessary and can be replaced with GFP_KERNEL,
to avoid busy waiting and improve the possibility of sucessful allocation.

This is found by a static analysis tool named DCNS written by myself.
And I also manually check it.

Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2018-04-09 17:48:54 +02:00
Dominik Brodowski ab0d1e85bf fs/quota: use COMPAT_SYSCALL_DEFINE for sys32_quotactl()
While sys32_quotactl() is only needed on x86, it can use the recommended
COMPAT_SYSCALL_DEFINEx() machinery for its setup.

Acked-by: Jan Kara <jack@suse.cz>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
2018-04-02 20:15:47 +02:00
Dominik Brodowski cb0b476ab1 fs/quota: add kernel_quotactl() helper; remove in-kernel call to syscall
Using the fs-internal kernel_quotactl() helper allows us to get rid of
the fs-internal call to the sys_quotactl() syscall.

This patch is part of a series which removes in-kernel calls to syscalls.
On this basis, the syscall entry path can be streamlined. For details, see
http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net

Acked-by: Jan Kara <jack@suse.cz>
Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
2018-04-02 20:15:46 +02:00
Tetsuo Handa 88bc0ede8d quota: Check for register_shrinker() failure.
register_shrinker() might return -ENOMEM error since Linux 3.12.
Call panic() as with other failure checks in this function if
register_shrinker() failed.

Fixes: 1d3d4437ea ("vmscan: per-node deferred work")
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Jan Kara <jack@suse.com>
Cc: Michal Hocko <mhocko@suse.com>
Reviewed-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2017-11-29 16:46:48 +01:00
Chao Yu 1a6152d36d quota: propagate error from __dquot_initialize
In commit 6184fc0b8d ("quota: Propagate error from ->acquire_dquot()"),
we have propagated error from __dquot_initialize to caller, but we forgot
to handle such error in add_dquot_ref(), so, currently, during quota
accounting information initialization flow, if we failed for some of
inodes, we just ignore such error, and do account for others, which is
not a good implementation.

In this patch, we choose to let user be aware of such error, so after
turning on quota successfully, we can make sure all inodes disk usage
can be accounted, which will be more reasonable.

Suggested-by: Jan Kara <jack@suse.cz>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2017-11-28 16:08:08 +01:00
Linus Torvalds f14fc0ccee Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs
Pull quota, ext2, isofs and udf fixes from Jan Kara:

 - two small quota error handling fixes

 - two isofs fixes for architectures with signed char

 - several udf block number overflow and signedness fixes

 - ext2 rework of mount option handling to avoid GFP_KERNEL allocation
   with spinlock held

 - ... it also contains a patch to implement auditing of responses to
   fanotify permission events. That should have been in the fanotify
   pull request but I mistakenly merged that patch into a wrong branch
   and noticed only now at which point I don't think it's worth rebasing
   and redoing.

* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
  quota: be aware of error from dquot_initialize
  quota: fix potential infinite loop
  isofs: use unsigned char types consistently
  isofs: fix timestamps beyond 2027
  udf: Fix some sign-conversion warnings
  udf: Fix signed/unsigned format specifiers
  udf: Fix 64-bit sign extension issues affecting blocks > 0x7FFFFFFF
  udf: Remove some outdate references from documentation
  udf: Avoid overflow when session starts at large offset
  ext2: Fix possible sleep in atomic during mount option parsing
  ext2: Parse mount options into a dedicated structure
  audit: Record fanotify access control decisions
2017-11-14 14:13:11 -08:00
Jan Kara 838bee9e75 Merge udf, isofs, quota, ext2 changes for 4.15-rc1. 2017-11-14 11:09:53 +01:00
Chao Yu 88d8ff976a quota: be aware of error from dquot_initialize
Commit 6184fc0b8d ("quota: Propagate error from ->acquire_dquot()")
missed to handle error from dquot_initialize in dquot_file_open, fix it.

Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2017-11-13 10:36:56 +01:00
Greg Kroah-Hartman b24413180f License cleanup: add SPDX GPL-2.0 license identifier to files with no license
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained >5
   lines of source
 - File already had some variant of a license header in it (even if <5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02 11:10:55 +01:00
zhangyi (F) dd5f627973 quota: fix potential infinite loop
In dquot_writeback_dquots(), we write back dquot from dirty dquots
list. There is a potential infinite loop if ->write_dquot() failure
and forget remove dquot from the list. This patch clear dirty bit
anyway to avoid it.

Signed-off-by: zhangyi (F) <yi.zhang@huawei.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2017-11-01 14:42:57 +01:00
Jan Kara ac3d79392f quota: Generate warnings for DQUOT_SPACE_NOFAIL allocations
Eryu has reported that since commit 7b9ca4c61b "quota: Reduce
contention on dq_data_lock" test generic/233 occasionally fails. This is
caused by the fact that since that commit we don't generate warning and
set grace time for quota allocations that have DQUOT_SPACE_NOFAIL set
(these are for example some metadata allocations in ext4). We need these
allocations to behave regularly wrt warning generation and grace time
setting so fix the code to return to the original behavior.

Reported-and-tested-by: Eryu Guan <eguan@redhat.com>
CC: stable@vger.kernel.org
Fixes: 7b9ca4c61b
Signed-off-by: Jan Kara <jack@suse.cz>
2017-10-10 17:24:46 +02:00
Jan Kara 4c6bb69663 quota: Fix quota corruption with generic/232 test
Eric has reported that since commit d2faa41516 "quota: Do not acquire
dqio_sem for dquot overwrites in v2 format" test generic/232
occasionally fails due to quota information being incorrect. Indeed that
commit was too eager to remove dqio_sem completely from the path that
just overwrites quota structure with updated information. Although that
is innocent on its own, another process that inserts new quota structure
to the same block can perform read-modify-write cycle of that block thus
effectively discarding quota information update if they race in a wrong
way.

Fix the problem by acquiring dqio_sem for reading for overwrites of
quota structure. Note that it *is* possible to completely avoid taking
dqio_sem in the overwrite path however that will require modifying path
inserting / deleting quota structures to avoid RMW cycles of the full
block and for now it is not clear whether it is worth the hassle.

Fixes: d2faa41516
Reported-and-tested-by: Eric Whitney <enwlinux@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2017-09-27 11:33:47 +02:00
Konstantin Khlebnikov 0a51fb7174 quota: add missing lock into __dquot_transfer()
Lock dq_dqb_lock around dquot_decr_inodes()

Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Fixes: 7b9ca4c61b ("quota: Reduce contention on dq_data_lock")
Signed-off-by: Jan Kara <jack@suse.cz>
2017-09-18 12:23:58 +02:00
Linus Torvalds 0f0d12728e Merge branch 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull mount flag updates from Al Viro:
 "Another chunk of fmount preparations from dhowells; only trivial
  conflicts for that part. It separates MS_... bits (very grotty
  mount(2) ABI) from the struct super_block ->s_flags (kernel-internal,
  only a small subset of MS_... stuff).

  This does *not* convert the filesystems to new constants; only the
  infrastructure is done here. The next step in that series is where the
  conflicts would be; that's the conversion of filesystems. It's purely
  mechanical and it's better done after the merge, so if you could run
  something like

	list=$(for i in MS_RDONLY MS_NOSUID MS_NODEV MS_NOEXEC MS_SYNCHRONOUS MS_MANDLOCK MS_DIRSYNC MS_NOATIME MS_NODIRATIME MS_SILENT MS_POSIXACL MS_KERNMOUNT MS_I_VERSION MS_LAZYTIME; do git grep -l $i fs drivers/staging/lustre drivers/mtd ipc mm include/linux; done|sort|uniq|grep -v '^fs/namespace.c$')

	sed -i -e 's/\<MS_RDONLY\>/SB_RDONLY/g' \
	        -e 's/\<MS_NOSUID\>/SB_NOSUID/g' \
	        -e 's/\<MS_NODEV\>/SB_NODEV/g' \
	        -e 's/\<MS_NOEXEC\>/SB_NOEXEC/g' \
	        -e 's/\<MS_SYNCHRONOUS\>/SB_SYNCHRONOUS/g' \
	        -e 's/\<MS_MANDLOCK\>/SB_MANDLOCK/g' \
	        -e 's/\<MS_DIRSYNC\>/SB_DIRSYNC/g' \
	        -e 's/\<MS_NOATIME\>/SB_NOATIME/g' \
	        -e 's/\<MS_NODIRATIME\>/SB_NODIRATIME/g' \
	        -e 's/\<MS_SILENT\>/SB_SILENT/g' \
	        -e 's/\<MS_POSIXACL\>/SB_POSIXACL/g' \
	        -e 's/\<MS_KERNMOUNT\>/SB_KERNMOUNT/g' \
	        -e 's/\<MS_I_VERSION\>/SB_I_VERSION/g' \
	        -e 's/\<MS_LAZYTIME\>/SB_LAZYTIME/g' \
	        $list

  and commit it with something along the lines of 'convert filesystems
  away from use of MS_... constants' as commit message, it would save a
  quite a bit of headache next cycle"

* 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  VFS: Differentiate mount flags (MS_*) from internal superblock flags
  VFS: Convert sb->s_flags & MS_RDONLY to sb_rdonly(sb)
  vfs: Add sb_rdonly(sb) to query the MS_RDONLY flag on s_flags
2017-09-14 18:54:01 -07:00
Linus Torvalds ae8ac6b7db Merge branch 'quota_scaling' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs
Pull quota scaling updates from Jan Kara:
 "This contains changes to make the quota subsystem more scalable.

  Reportedly it improves number of files created per second on ext4
  filesystem on fast storage by about a factor of 2x"

* 'quota_scaling' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs: (28 commits)
  quota: Add lock annotations to struct members
  quota: Reduce contention on dq_data_lock
  fs: Provide __inode_get_bytes()
  quota: Inline dquot_[re]claim_reserved_space() into callsite
  quota: Inline inode_{incr,decr}_space() into callsites
  quota: Inline functions into their callsites
  ext4: Disable dirty list tracking of dquots when journalling quotas
  quota: Allow disabling tracking of dirty dquots in a list
  quota: Remove dq_wait_unused from dquot
  quota: Move locking into clear_dquot_dirty()
  quota: Do not dirty bad dquots
  quota: Fix possible corruption of dqi_flags
  quota: Propagate ->quota_read errors from v2_read_file_info()
  quota: Fix error codes in v2_read_file_info()
  quota: Push dqio_sem down to ->read_file_info()
  quota: Push dqio_sem down to ->write_file_info()
  quota: Push dqio_sem down to ->get_next_id()
  quota: Push dqio_sem down to ->release_dqblk()
  quota: Remove locking for writing to the old quota format
  quota: Do not acquire dqio_sem for dquot overwrites in v2 format
  ...
2017-09-07 15:19:35 -07:00
Markus Elfring 434aafb572 quota_v2: Delete an error message for a failed memory allocation in v2_read_file_info()
Omit an extra message for a memory allocation failure in this function.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Jan Kara <jack@suse.cz>
2017-08-21 16:02:59 +02:00
Jan Kara 7b9ca4c61b 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>
2017-08-17 22:07:59 +02:00
Jan Kara 3ab167d2ba quota: Inline dquot_[re]claim_reserved_space() into callsite
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>
2017-08-17 22:03:03 +02:00
Jan Kara a478e522e3 quota: Inline inode_{incr,decr}_space() into callsites
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>
2017-08-17 22:01:14 +02:00
Jan Kara 0ed60de34a quota: Inline functions into their callsites
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>
2017-08-17 22:00:59 +02:00
Jan Kara 834057bf84 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>
2017-08-17 22:00:45 +02:00
Jan Kara 503330f382 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>
2017-08-17 22:00:40 +02:00
Jan Kara 1e0b7cb062 quota: Move locking into clear_dquot_dirty()
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>
2017-08-17 22:00:24 +02:00
Jan Kara 4580b30ea8 quota: Do not dirty bad dquots
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>
2017-08-17 22:00:07 +02:00
Jan Kara 15512377bd quota: Fix possible corruption of dqi_flags
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>
2017-08-17 22:00:04 +02:00
Jan Kara f98bbe37ae quota: Propagate ->quota_read errors from v2_read_file_info()
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>
2017-08-17 19:20:28 +02:00