[ Upstream commit 8877243bea ]
Syzkaller has reported a NULL pointer dereference when accessing
rgd->rd_rgl in gfs2_rgrp_dump(). This can happen when creating
rgd->rd_gl fails in read_rindex_entry(). Add a NULL pointer check in
gfs2_rgrp_dump() to prevent that.
Reported-and-tested-by: syzbot+da0fc229cc1ff4bb2e6d@syzkaller.appspotmail.com
Link: https://syzkaller.appspot.com/bug?extid=da0fc229cc1ff4bb2e6d
Fixes: 72244b6bc7 ("gfs2: improve debug information when lvb mismatches are found")
Signed-off-by: Osama Muhammad <osmtendev@gmail.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 0cdc6f44e9 upstream.
In gfs2_fill_super(), when mounting a gfs2 filesystem is interrupted,
kthread_create() can return -EINTR. When that happens, we roll back
what has already been done and abort the mount.
Since commit 62dd0f98a0 ("gfs2: Flag a withdraw if init_threads()
fails), we are calling gfs2_withdraw_delayed() in gfs2_fill_super();
first via gfs2_make_fs_rw(), then directly. But gfs2_withdraw_delayed()
only marks the filesystem as withdrawing and relies on a caller further
up the stack to do the actual withdraw, which doesn't exist in the
gfs2_fill_super() case. Because the filesystem is marked as withdrawing
/ withdrawn, function gfs2_lm_unmount() doesn't release the dlm
lockspace, so when we try to mount that filesystem again, we get:
gfs2: fsid=gohan:gohan0: Trying to join cluster "lock_dlm", "gohan:gohan0"
gfs2: fsid=gohan:gohan0: dlm_new_lockspace error -17
Since commit b77b4a4815 ("gfs2: Rework freeze / thaw logic"), the
deadlock this gfs2_withdraw_delayed() call was supposed to work around
cannot occur anymore because freeze_go_callback() won't take the
sb->s_umount semaphore unconditionally anymore, so we can get rid of the
gfs2_withdraw_delayed() in gfs2_fill_super() entirely.
Reported-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Cc: stable@vger.kernel.org # v6.5+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 074d7306a4 ]
Commit 0abd1557e2 added rcu_dereference() for dereferencing ip->i_gl
in gfs2_permission. This now causes lockdep to complain when
gfs2_permission is called in non-RCU context:
WARNING: suspicious RCU usage in gfs2_permission
Switch to rcu_dereference_check() and check for the MAY_NOT_BLOCK flag
to shut up lockdep when we know that dereferencing ip->i_gl is safe.
Fixes: 0abd1557e2 ("gfs2: fix an oops in gfs2_permission")
Reported-by: syzbot+3e5130844b0c0e2b4948@syzkaller.appspotmail.com
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit bdcb8aa434 ]
In gfs2_put_super(), whether withdrawn or not, the quota should
be cleaned up by gfs2_quota_cleanup().
Otherwise, struct gfs2_sbd will be freed before gfs2_qd_dealloc (rcu
callback) has run for all gfs2_quota_data objects, resulting in
use-after-free.
Also, gfs2_destroy_threads() and gfs2_quota_cleanup() is already called
by gfs2_make_fs_ro(), so in gfs2_put_super(), after calling
gfs2_make_fs_ro(), there is no need to call them again.
Reported-by: syzbot+29c47e9e51895928698c@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=29c47e9e51895928698c
Signed-off-by: Juntong Deng <juntong.deng@outlook.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 0abd1557e2 ]
In RCU mode, we might race with gfs2_evict_inode(), which zeroes
->i_gl. Freeing of the object it points to is RCU-delayed, so
if we manage to fetch the pointer before it's been replaced with
NULL, we are fine. Check if we'd fetched NULL and treat that
as "bail out and tell the caller to get out of RCU mode".
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 4c6a08125f ]
When lots of quota changes are made, there may be cases in which an
inode's quota information is increased and then decreased, such as when
blocks are added to a file, then deleted from it. If the timing is
right, function do_qc can add pending quota changes to a transaction,
then later, another call to do_qc can negate those changes, resulting
in a net gain of 0. The quota_change information is recorded in the qc
buffer (and qd element of the inode as well). The buffer is added to the
transaction by the first call to do_qc, but a subsequent call changes
the value from non-zero back to zero. At that point it's too late to
remove the buffer_head from the transaction. Later, when the quota sync
code is called, the zero-change qd element is discovered and flagged as
an assert warning. If the fs is mounted with errors=panic, the kernel
will panic.
This is usually seen when files are truncated and the quota changes are
negated by punch_hole/truncate which uses gfs2_quota_hold and
gfs2_quota_unhold rather than block allocations that use gfs2_quota_lock
and gfs2_quota_unlock which automatically do quota sync.
This patch solves the problem by adding a check to qd_check_sync such
that net-zero quota changes already added to the transaction are no
longer deemed necessary to be synced, and skipped.
In this case references are taken for the qd and the slot from do_qc
so those need to be put. The normal sequence of events for a normal
non-zero quota change is as follows:
gfs2_quota_change
do_qc
qd_hold
slot_hold
Later, when the changes are to be synced:
gfs2_quota_sync
qd_fish
qd_check_sync
gets qd ref via lockref_get_not_dead
do_sync
do_qc(QC_SYNC)
qd_put
lockref_put_or_lock
qd_unlock
qd_put
lockref_put_or_lock
In the net-zero change case, we add a check to qd_check_sync so it puts
the qd and slot references acquired in gfs2_quota_change and skip the
unneeded sync.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Patch eef46ab713 introduced a new gfs2 quota=quiet mount option.
Checks for the new option were added to quota.c, but a check in
gfs2_quota_lock_check() was overlooked. This patch adds the missing
check.
Fixes: eef46ab713 ("gfs2: Introduce new quota=quiet mount option")
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Before this patch, function gfs2_scan_glock_lru would only try to free
glocks that had a reference count of 0. But if the reference count ever
got to 0, the glock should have already been freed.
Shrinker function gfs2_dispose_glock_lru checks whether glocks on the
LRU are demote_ok, and if so, tries to demote them. But that's only
possible if the reference count is at least 1.
This patch changes gfs2_scan_glock_lru so it will try to demote and/or
dispose of glocks that have a reference count of 1 and which are either
demotable, or are already unlocked.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
On a thawed filesystem, the freeze glock is held in shared mode. In
order to initiate a cluster-wide freeze, the node initiating the freeze
drops the freeze glock and grabs it in exclusive mode. The other nodes
recognize this as contention on the freeze glock; function
freeze_go_callback is invoked. This indicates to them that they must
freeze the filesystem locally, drop the freeze glock, and then
re-acquire it in shared mode before being able to unfreeze the
filesystem locally.
While a node is trying to re-acquire the freeze glock in shared mode,
additional contention can occur. In that case, the node must behave in
the same way as above.
Unfortunately, freeze_go_callback() contains a check that causes it to
bail out when the freeze glock isn't held in shared mode. Fix that to
allow the glock to be unlocked or held in shared mode.
In addition, update a reference to trylock_super() which has been
renamed to super_trylock_shared() in the meantime.
Fixes: b77b4a4815 ("gfs2: Rework freeze / thaw logic")
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
- Fix a glock state (non-)transition bug when a dlm request times out
and is canceled, and we have locking requests that can now be granted
immediately.
- Various fixes and cleanups in how the logd and quotad daemons are
woken up and terminated.
- Fix several bugs in the quota data reference counting and shrinking.
Free quota data objects synchronously in put_super() instead of
letting call_rcu() run wild.
- Make sure not to deallocate quota data during a withdraw; rather, defer
quota data deallocation to put_super(). Withdraws can happen in
contexts in which callers on the stack are holding quota data references.
- Many minor quota fixes and cleanups by Bob.
- Update the the mailing list address for gfs2 and dlm. (It's the same
list for both and we are moving it to gfs2@lists.linux.dev.)
- Various other minor cleanups.
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Merge tag 'gfs2-v6.5-rc5-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2
Pull gfs2 updates from Andreas Gruenbacher:
- Fix a glock state (non-)transition bug when a dlm request times out
and is canceled, and we have locking requests that can now be granted
immediately
- Various fixes and cleanups in how the logd and quotad daemons are
woken up and terminated
- Fix several bugs in the quota data reference counting and shrinking.
Free quota data objects synchronously in put_super() instead of
letting call_rcu() run wild
- Make sure not to deallocate quota data during a withdraw; rather,
defer quota data deallocation to put_super(). Withdraws can happen in
contexts in which callers on the stack are holding quota data
references
- Many minor quota fixes and cleanups by Bob
- Update the the mailing list address for gfs2 and dlm. (It's the same
list for both and we are moving it to gfs2@lists.linux.dev)
- Various other minor cleanups
* tag 'gfs2-v6.5-rc5-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2: (51 commits)
MAINTAINERS: Update dlm mailing list
MAINTAINERS: Update gfs2 mailing list
gfs2: change qd_slot_count to qd_slot_ref
gfs2: check for no eligible quota changes
gfs2: Remove useless assignment
gfs2: simplify slot_get
gfs2: Simplify qd2offset
gfs2: introduce qd_bh_get_or_undo
gfs2: Remove quota allocation info from quota file
gfs2: use constant for array size
gfs2: Set qd_sync_gen in do_sync
gfs2: Remove useless err set
gfs2: Small gfs2_quota_lock cleanup
gfs2: move qdsb_put and reduce redundancy
gfs2: improvements to sysfs status
gfs2: Don't try to sync non-changes
gfs2: Simplify function need_sync
gfs2: remove unneeded pg_oflow variable
gfs2: remove unneeded variable done
gfs2: pass sdp to gfs2_write_buf_to_page
...
Variable qd_slot_count is a reference count, not a count of slots. This
patch renames it to qd_slot_ref to make that more clear.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Before this patch, function gfs2_quota_sync would always allocate a page
full of memory and increment its quota sync generation number. This
happened even when the system was completely idle or if no blocks were
allocated or quota changes made. This patch adds function qd_changed
to determine if any changes have been made that qualify for a
quota sync. If not, it avoids the memory allocation and bumping the
generation number, along with all the additional work it would do.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
This assignment is unnecessary because if error was not already 0, it
would have branched to an error label already.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Simplify function slot_get and get rid of the goto that jumps into the
middle of an else branch.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
This is a minor cleanup of function qd2offset.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
This patch is an attempt to force some consistency in quota sync
processing. Two functions (qd_fish and gfs2_quota_unlock) called
qd_check_sync, after which they both called bh_get, and if that failed,
they took the same steps to undo the actions of qd_check_sync.
This patch introduces a new function, qd_bh_get_or_undo, which performs
the same steps, reducing code redundancy.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Function do_sync called gfs2_qa_get and put for quota allocation data.
But the inode in question is the system master quota file, which is
never subject to quotas. Therefore, a qa structure should be unnecessary
and if anything accesses it, it's probably a bug.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Function gfs2_quota_unlock declared an array of 4 qd elements. We have a
constant for that, we should be using it.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Func do_sync was called in two places: gfs2_quota_unlock and
gfs2_quota_sync. In gfs2_quota_sync it updated qd_sync_gen to the latest
superblock sync gen, if do_sync was successful. In gfs2_quota_unlock it
didn't update the value. That can only lead to extra work, for example,
if the value is synced by gfs2_quota_unlock but still has the old value.
This patch moves the setting of qd_sync_gen inside do_sync so we are
guaranteed consistency.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Function gfs2_adjust_quota set variable err, then set it again to a
different value. This patch removes the redundant set.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
No need to set error = 0 since it's set further down.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
This patch looks more invasive than it is. It simply moves function
qdsb_put before qd_unlock, then changes qd_unlock to call it rather than
open coding it. Again, this reduces redundancy.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
This patch adds some new fields to the gfs2 status file in sysfs to aid
in debugging.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Function need_sync is supposed to determine if a qd element needs to be
synced. If the "change" (qd_change) is zero, it does not need to be
synced because there's literally no change in the value. Before this
patch need_sync returned false if value < 0. That should be <= 0.
This patch changes the check to <=.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
This patch simplifies function need_sync by eliminating a variable in
favor of just returning the appropriate value as soon as we know it.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Function gfs2_write_disk_quota checks if its write overflows onto
another page, and if so, does a second write. Before this patch it kept
two variables for this, but only one is needed. This patch simplifies
it by eliminating pg_oflow.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Function gfs2_write_buf_to_page uses variable done to exit its loop, but
it's unnecessary if we just code an infinite loop and exit when we need.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
This patch passes the superblock pointer to gfs2_write_buf_to_page so it
becomes more apparent it's dealing with the system quota file.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Like the previous patch, we now pass the superblock pointer to function
gfs2_write_disk_quota. This makes the code more understandable, since it
only operates on the quota inode.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Before this change function gfs2_adjust_quota's first parameter was an
gfs2_inode pointer. But it always pointed to the quota inode. Here we
switch that to pass the superblock pointer, sdp, so it is easier to read
the code and understand that it's only dealing with the quota inode.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Since patch 845802b112 function gfs2_write_buf_to_page checks if the
target inode is jdata or ordered. This function only operates on the
system quota file, which is always jdata, so the check for jdata is
useless. This patch removes it.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
This patch adds a new mount option quota=quiet which is the same as
quota=on but it suppresses gfs2 quota error messages.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Add the device name to the names of the gfs2_logd and gfs2_quotad kernel
threads to allow for easier identification.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Rename the "gfs_recovery" workqueue to "gfs2_recovery", and
gfs_recovery_wq to gfs2_recovery_wq.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Function gfs2_withdraw() tries to synchronize concurrent callers by
atomically setting the SDF_WITHDRAWN flag in the first caller, setting
the SDF_WITHDRAW_IN_PROG flag to indicate that a withdraw is in
progress, performing the actual withdraw, and clearing the
SDF_WITHDRAW_IN_PROG flag when done. All other callers wait for the
SDF_WITHDRAW_IN_PROG flag to be cleared before returning.
This leaves a small window in which callers can find the SDF_WITHDRAWN
flag set before the SDF_WITHDRAW_IN_PROG flag has been set, causing them
to return prematurely, before the withdraw has been completed.
Fix that by setting the SDF_WITHDRAWN and SDF_WITHDRAW_IN_PROG flags
atomically.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Immediately stop the logd and quotad kernel threads when a filesystem
withdraw is detected: those threads aren't doing anything useful after a
withdraw. (Depends on the extra logd and quotad task struct references
held since commit 7a109f383fa3 ("gfs2: Fix asynchronous thread
destruction").)
In addition, check for kthread_should_stop() in the wait condition in
gfs2_quotad() to stop immediately when kthread_stop() is called.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
The kernel threads are currently stopped and destroyed synchronously by
gfs2_make_fs_ro() and gfs2_put_super(), and asynchronously by
signal_our_withdraw(), with no synchronization, so the synchronous and
asynchronous contexts can race with each other.
First, when creating the kernel threads, take an extra task struct
reference so that the task struct won't go away immediately when they
terminate. This allows those kthreads to terminate immediately when
they're done rather than hanging around as zombies until they are reaped
by kthread_stop(). When kthread_stop() is called on a terminated
kthread, it will return immediately.
Second, in signal_our_withdraw(), once the SDF_JOURNAL_LIVE flag has
been cleared, wake up the logd and quotad wait queues instead of
stopping the logd and quotad kthreads. The kthreads are then expected
to terminate automatically within short time, but if they cannot, they
will not block the withdraw.
For example, if a user process and one of the kthread decide to withdraw
at the same time, only one of them will perform the actual withdraw and
the other will wait for it to be done. If the kthread ends up being the
one to wait, the withdrawing user process won't be able to stop it.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
[ 81.372851][ T5532] CPU: 1 PID: 5532 Comm: syz-executor.0 Not tainted 6.2.0-rc1-syzkaller-dirty #0
[ 81.382080][ T5532] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/12/2023
[ 81.392343][ T5532] Call Trace:
[ 81.395654][ T5532] <TASK>
[ 81.398603][ T5532] dump_stack_lvl+0x1b1/0x290
[ 81.418421][ T5532] gfs2_assert_warn_i+0x19a/0x2e0
[ 81.423480][ T5532] gfs2_quota_cleanup+0x4c6/0x6b0
[ 81.428611][ T5532] gfs2_make_fs_ro+0x517/0x610
[ 81.457802][ T5532] gfs2_withdraw+0x609/0x1540
[ 81.481452][ T5532] gfs2_inode_refresh+0xb2d/0xf60
[ 81.506658][ T5532] gfs2_instantiate+0x15e/0x220
[ 81.511504][ T5532] gfs2_glock_wait+0x1d9/0x2a0
[ 81.516352][ T5532] do_sync+0x485/0xc80
[ 81.554943][ T5532] gfs2_quota_sync+0x3da/0x8b0
[ 81.559738][ T5532] gfs2_sync_fs+0x49/0xb0
[ 81.564063][ T5532] sync_filesystem+0xe8/0x220
[ 81.568740][ T5532] generic_shutdown_super+0x6b/0x310
[ 81.574112][ T5532] kill_block_super+0x79/0xd0
[ 81.578779][ T5532] deactivate_locked_super+0xa7/0xf0
[ 81.584064][ T5532] cleanup_mnt+0x494/0x520
[ 81.593753][ T5532] task_work_run+0x243/0x300
[ 81.608837][ T5532] exit_to_user_mode_loop+0x124/0x150
[ 81.614232][ T5532] exit_to_user_mode_prepare+0xb2/0x140
[ 81.619820][ T5532] syscall_exit_to_user_mode+0x26/0x60
[ 81.625287][ T5532] do_syscall_64+0x49/0xb0
[ 81.629710][ T5532] entry_SYSCALL_64_after_hwframe+0x63/0xcd
In this backtrace, gfs2_quota_sync() takes quota data references and
then calls do_sync(). Function do_sync() encounters filesystem
corruption and withdraws the filesystem, which (among other things) calls
gfs2_quota_cleanup(). Function gfs2_quota_cleanup() wrongly assumes
that nobody is holding any quota data references anymore, and destroys
all quota data objects. When gfs2_quota_sync() then resumes and
dereferences the quota data objects it is holding, those objects are no
longer there.
Function gfs2_quota_cleanup() deals with resource deallocation and can
easily be delayed until gfs2_put_super() in the case of a filesystem
withdraw. In fact, most of the other work gfs2_make_fs_ro() does is
unnecessary during a withdraw as well, so change signal_our_withdraw()
to skip gfs2_make_fs_ro() and perform the necessary steps directly
instead.
Thanks to Edward Adam Davis <eadavis@sina.com> for the initial patches.
Link: https://lore.kernel.org/all/0000000000002b5e2405f14e860f@google.com
Reported-by: syzbot+3f6a670108ce43356017@syzkaller.appspotmail.com
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
In gfs2_quota_cleanup(), wait for the quota data objects to be freed
before returning. Otherwise, there is no guarantee that the quota data
objects will be gone when their kmem cache is destroyed.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Fix the refcount of quota data objects created directly by
gfs2_quota_init(): those are placed into the in-memory quota "database"
for eventual syncing to the main quota file, but they are not actively
held and should thus have an initial refcount of 0.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Once a filesystem is withdrawn, don't complain about quota changes
that can't be synced to the main quota file anymore.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Rename gfs2_qd_dispose() to gfs2_qd_dispose_list(). Move some code
duplicated in gfs2_qd_dispose_list() and gfs2_quota_cleanup() into a
new gfs2_qd_dispose() function.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Change gfs2_quota_cleanup() to move the quota data objects to dispose of
on a dispose list and call gfs2_qd_dispose() on that list, like
gfs2_qd_shrink_scan() does, instead of disposing of the quota data
objects directly.
This may look a bit pointless by itself, but it will make more sense in
combination with a fix that follows.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Function gfs2_qd_isolate must only return LRU_REMOVED when removing the
item from the lru list; otherwise, the number of items on the list will
go wrong.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Rename the SDF_DEACTIVATING flag to SDF_KILL to make it more obvious
that this relates to the kill_sb filesystem operation.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Rename sd_glock_wait to sd_kill_wait: we'll use it for other things
related to "killing" a filesystem on unmount soon (kill_sb).
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Before this patch many of the functions in quota.c got their superblock
pointer, sdp, from the quota_data's glock pointer. That's silly because
the qd already has its own pointer to the superblock (qd_sbd).
This patch changes references to use that instead, eliminating a level
of indirection.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
