Christoph suggests:
"Add a return value to lm_break so that the lock manager can tell the
core code "you can delete this lease right now". That gets rid of
the games with the timeout which require all kinds of race avoidance
code in the users."
Do that here and have the nfsd lease break routine use it when it detects
that there was a race between setting up the lease and it being broken.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Eliminate an unneeded "flock" variable. We can use "fl" as a loop cursor
everywhere. Add a any_leases_conflict helper function as well to
consolidate a bit of code.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
I think that the intent of this code was to ensure that a process won't
deadlock if it has one fd open with a lease on it and then breaks that
lease by opening another fd. In that case it'll treat the __break_lease
call as if it were non-blocking.
This seems wrong -- the process could (for instance) be multithreaded
and managing different fds via different threads. I also don't see any
mention of this limitation in the (somewhat sketchy) documentation.
Remove the check and the non-blocking behavior when i_have_this_lease
is true.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
There was only one place where we still could free a file_lock while
holding the i_lock -- lease_modify. Add a new list_head argument to the
lm_change operation, pass in a private list when calling it, and fix
those callers to dispose of the list once the lock has been dropped.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Now that we have a saner internal API for managing leases, we no longer
need to mandate that the inode->i_lock be held over most of the lease
code. Push it down into generic_add_lease and generic_delete_lease.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
...and move the fasync setup into it for fcntl lease calls. At the same
time, change the semantics of how the file_lock double-pointer is
handled. Up until now, on a successful lease return you got a pointer to
the lock on the list. This is bad, since that pointer can no longer be
relied on as valid once the inode->i_lock has been released.
Change the code to instead just zero out the pointer if the lease we
passed in ended up being used. Then the callers can just check to see
if it's NULL after the call and free it if it isn't.
The priv argument has the same semantics. The lm_setup function can
zero the pointer out to signal to the caller that it should not be
freed after the function returns.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
In later patches, we're going to add a new lock_manager_operation to
finish setting up the lease while still holding the i_lock. To do
this, we'll need to pass a little bit of info in the fcntl setlease
case (primarily an fasync structure). Plumb the extra pointer into
there in advance of that.
We declare this pointer as a void ** to make it clear that this is
private info, and that the caller isn't required to set this unless
the lm_setup specifically requires it.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Now that we don't need to pass in an actual lease pointer to
vfs_setlease on unlock, we can stop tracking a pointer to the lease in
the nfs4_file.
Switch all of the places that check the fi_lease to check fi_deleg_file
instead. We always set that at the same time so it will have the same
semantics.
Cc: J. Bruce Fields <bfields@fieldses.org>
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Some of the latter paragraphs seem ambiguous and just plain wrong.
In particular the break_lease comment makes no sense. We call
break_lease (and break_deleg) from all sorts of vfs-layer functions,
so there is clearly such a method.
Also get rid of some of the other comments about what's needed for
a full implementation.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Ensure that it's OK to pass in a NULL file_lock double pointer on
a F_UNLCK request and convert the vfs_setlease F_UNLCK callers to
do just that.
Finally, turn the BUG_ON in generic_setlease into a WARN_ON_ONCE
with an error return. That's a problem we can handle without
crashing the box if it occurs.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
It's unlikely to ever occur, but if there were already a lease set on
the file then we could end up getting back a different pointer on a
successful setlease attempt than the one we allocated. If that happens,
the one we allocated could leak.
In practice, I don't think this will happen due to the fact that we only
try to set up the lease once per nfs4_file, but this error handling is a
bit more correct given the current lease API.
Cc: J. Bruce Fields <bfields@fieldses.org>
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
lease_get_mtime is called without the i_lock held, so there's no
guarantee about the stability of the list. Between the time when we
assign "flock" and then dereference it to check whether it's a lease
and for write, the lease could be freed.
Ensure that that doesn't occur by taking the i_lock before trying
to check the lease.
Cc: J. Bruce Fields <bfields@fieldses.org>
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
security_file_set_fowner always returns 0, so make it f_setown and
__f_setown void return functions and fix up the error handling in the
callers.
Cc: linux-security-module@vger.kernel.org
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
GFS2 and NFS have setlease routines that always just return -EINVAL.
Turn that into a generic routine that can live in fs/libfs.c.
Cc: <linux-nfs@vger.kernel.org>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: <cluster-devel@redhat.com>
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Acked-by: Trond Myklebust <trond.myklebust@primarydata.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
As Kinglong points out, the nlm_block->b_fl field is no longer used at
all. Also, vfs_test_lock in the generic locking code will only return
FILE_LOCK_DEFERRED if FL_SLEEP is set, and it isn't here.
The only other place that returns that value is the DLM lock code, but
it only does that in dlm_posix_lock, never in dlm_posix_get.
Remove all of the deferred locking code from the testlock codepath
since it doesn't appear to ever be used anyway.
I do have a small concern that this might cause a behavior change in the
case where you have a block already sitting on the list when the
testlock request comes in, but that looks like it doesn't really work
properly anyway. I think it's best to just pass that down to
vfs_test_lock and let the filesystem report that instead of trying to
infer what's going on with the lock by looking at an existing block.
Cc: cluster-devel@redhat.com
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Reviewed-by: Kinglong Mee <kinglongmee@gmail.com>
v5: using nfs4_get_stateowner() instead of an inline function
v3: Update based on Jeff's comments
v2: Fix bad using of struct file_lock_operations for handle the owner
Acked-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
v5: same as the first version
Reviewed-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Commit d5b9026a67 ([PATCH] knfsd: locks: flag NFSv4-owned locks) using
fl_lmops field in file_lock for checking nfsd4 lockowner.
But, commit 1a747ee0cc (locks: don't call ->copy_lock methods on return
of conflicting locks) causes the fl_lmops of conflock always be NULL.
Also, commit 0996905f93 (lockd: posix_test_lock() should not call
locks_copy_lock()) caused the fl_lmops of conflock always be NULL too.
Make sure copy the private information by fl_copy_lock() in struct
file_lock_operations, merge __locks_copy_lock() to fl_copy_lock().
Jeff advice, "Set fl_lmops on conflocks, but don't set fl_ops.
fl_ops are superfluous, since they are callbacks into the filesystem.
There should be no need to bother the filesystem at all with info
in a conflock. But, lock _ownership_ matters for conflocks and that's
indicated by the fl_lmops. So you really do want to copy the fl_lmops
for conflocks I think."
v5: add missing calling of locks_release_private() in nlmsvc_testlock()
v4: only copy fl_lmops for conflock, don't copy fl_ops
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
NFSD or other lockmanager may increase the owner's reference,
so adds two new options for copying and releasing owner.
v5: change order from 2/6 to 3/6
v4: rename lm_copy_owner/lm_release_owner to lm_get_owner/lm_put_owner
Reviewed-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Jeff advice, " Right now __locks_copy_lock is only used to copy
conflocks. It would be good to rename that to something more
distinct (i.e.locks_copy_conflock), to make it clear that we're
generating a conflock there."
v5: change order from 3/6 to 2/6
v4: new patch only renaming function name
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
This argument is always NULL so don't pass it around.
[jlayton: remove dependencies on previous patches in series]
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
The argument to locks_unlink_lock can't be just any pointer to a
pointer. It must be a pointer to the fl_next field in the previous
lock in the list.
Cc: <stable@vger.kernel.org> # v3.15+
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
This fixes an Oopsable race when starting up the callback server.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Reviewed-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
This fixes an Oopsable race when starting lockd.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Reviewed-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
The working group appears committed to keeping the protocol stable, the
code has gotten some use and seems to work OK.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Recent NFS v4.2 drafts have removed NFS4ERR_METADATA_NOTSUPP and
reassigned the error code to NFS4ERR_UNION_NOTSUPP.
I also add in the NFS4ERR_OFFLOAD_NO_REQS error code.
We're not using any of these yet, so there's no harm done.
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
locks_alloc_lock() has initialized struct file_lock, no need to
re-initialize it here.
Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
Reviewed-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
One of our customer's application only needs file names, not file
attributes. With directories having 10K+ inodes (assuming buffer cache
has directory blocks cached having file names, but inode cache is
limited and hence need eviction of older cached inodes), older inodes
are evicted periodically. So if they keep on doing readdir(2) from NSF
client on multiple directories, some directory's files are periodically
removed from inode cache and hence new readdir(2) on same directory
requires disk access to bring back inodes again to inode cache.
As READDIRPLUS request fetches attributes also, doing getattr on each
file on server, it causes unnecessary disk accesses. If READDIRPLUS on
NFS client is returned with -ENOTSUPP, NFS client uses READDIR request
which just gets the names of the files in a directory, not attributes,
hence avoiding disk accesses on server.
There's already a corresponding client-side mount option, but an export
option reduces the need for configuration across multiple clients.
This flag affects NFSv3 only. If it turns out it's needed for NFSv4 as
well then we may have to figure out how to extend the behavior to NFSv4,
but it's not currently obvious how to do that.
Signed-off-by: Rajesh Ghanekar <rajesh_ghanekar@symantec.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
As of 8c7424cff6 "nfsd4: don't try to encode conflicting owner if low
on space", we permit the server to process a LOCK operation even if
there might not be space to return the conflicting lockowner, because
we've made returning the conflicting lockowner optional.
However, the rpc server still wants to know the most we might possibly
return, so we need to take into account the possible conflicting
lockowner in the svc_reserve_space() call here.
Symptoms were log messages like "RPC request reserved 88 but used 108".
Fixes: 8c7424cff6 "nfsd4: don't try to encode conflicting owner if low on space"
Reported-by: Kinglong Mee <kinglongmee@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
When creating a file that already exists in a read-only directory with
O_EXCL, the NFSv3 server returns EACCES rather than EEXIST (which local
files and the NFSv4 server return). Fix this by checking the MAY_CREATE
permission only if the file does not exist. Since this already happens
in do_nfsd_create, the check in nfsd3_proc_create can simply be removed.
Signed-off-by: Ross Lagerwall <rosslagerwall@gmail.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Currently, we hold the state_lock when releasing the lease. That's
potentially problematic in the future if we allow for setlease methods
that can sleep. Move the nfs4_put_deleg_lease call out of the delegation
unhashing routine (which was always a bit goofy anyway), and into the
unlocked sections of the callers of unhash_delegation_locked.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Currently these fields are protected with the state_lock, but that
doesn't really make a lot of sense. These fields are "private" to the
nfs4_file, and can be protected with the more granular fi_lock.
The fi_lock is already held when setting these fields. Make the code
hold the fp->fi_lock when clearing the lease-related fields in the
nfs4_file, and no longer require that the state_lock be held when
calling into this function.
To prevent lock inversion with the i_lock, we also move the vfs_setlease
and fput calls outside of the fi_lock. This also sets us up for allowing
vfs_setlease calls to block in the future.
Finally, remove a redundant NULL pointer check. unhash_delegation_locked
locks the fp->fi_lock prior to that check, so fp in that function must
never be NULL.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
We would normally expect the xid and the checksum to be the best
discriminators. Check them before looking at the procedure number,
etc.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
...so we can remove the spinlocking around it.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Now that the lru list is per-bucket, we don't need a second list for
searches.
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Pull btrfs updates from Chris Mason:
"These are all fixes I'd like to get out to a broader audience.
The biggest of the bunch is Mark's quota fix, which is also in the
SUSE kernel, and makes our subvolume quotas dramatically more
accurate.
I've been running xfstests with these against your current git
overnight, but I'm queueing up longer tests as well"
* 'for-linus2' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
btrfs: disable strict file flushes for renames and truncates
Btrfs: fix csum tree corruption, duplicate and outdated checksums
Btrfs: Fix memory corruption by ulist_add_merge() on 32bit arch
Btrfs: fix compressed write corruption on enospc
btrfs: correctly handle return from ulist_add
btrfs: qgroup: account shared subtrees during snapshot delete
Btrfs: read lock extent buffer while walking backrefs
Btrfs: __btrfs_mod_ref should always use no_quota
btrfs: adjust statfs calculations according to raid profiles
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Merge tag 'locks-v3.17-2' of git://git.samba.org/jlayton/linux
Pull file locking bugfixes from Jeff Layton:
"Most of these patches are to fix a long-standing regression that crept
in when the BKL was removed from the file-locking code. The code was
converted to use a conventional spinlock, but some fl_release_private
ops can block and you can end up sleeping inside the lock.
There's also a patch to make /proc/locks show delegations as 'DELEG'"
* tag 'locks-v3.17-2' of git://git.samba.org/jlayton/linux:
locks: update Locking documentation to clarify fl_release_private behavior
locks: move locks_free_lock calls in do_fcntl_add_lease outside spinlock
locks: defer freeing locks in locks_delete_lock until after i_lock has been dropped
locks: don't reuse file_lock in __posix_lock_file
locks: don't call locks_release_private from locks_copy_lock
locks: show delegations as "DELEG" in /proc/locks
Pull aio updates from Ben LaHaise.
* git://git.kvack.org/~bcrl/aio-next:
aio: use iovec array rather than the single one
aio: fix some comments
aio: use the macro rather than the inline magic number
aio: remove the needless registration of ring file's private_data
aio: remove no longer needed preempt_disable()
aio: kill the misleading rcu read locks in ioctx_add_table() and kill_ioctx()
aio: change exit_aio() to load mm->ioctx_table once and avoid rcu_read_lock()
Truncates and renames are often used to replace old versions of a file
with new versions. Applications often expect this to be an atomic
replacement, even if they haven't done anything to make sure the new
version is fully on disk.
Btrfs has strict flushing in place to make sure that renaming over an
old file with a new file will fully flush out the new file before
allowing the transaction commit with the rename to complete.
This ordering means the commit code needs to be able to lock file pages,
and there are a few paths in the filesystem where we will try to end a
transaction with the page lock held. It's rare, but these things can
deadlock.
This patch removes the ordered flushes and switches to a best effort
filemap_flush like ext4 uses. It's not perfect, but it should fix the
deadlocks.
Signed-off-by: Chris Mason <clm@fb.com>
Under rare circumstances we can end up leaving 2 versions of a checksum
for the same file extent range.
The reason for this is that after calling btrfs_next_leaf we process
slot 0 of the leaf it returns, instead of processing the slot set in
path->slots[0]. Most of the time (by far) path->slots[0] is 0, but after
btrfs_next_leaf() releases the path and before it searches for the next
leaf, another task might cause a split of the next leaf, which migrates
some of its keys to the leaf we were processing before calling
btrfs_next_leaf(). In this case btrfs_next_leaf() returns again the
same leaf but with path->slots[0] having a slot number corresponding
to the first new key it got, that is, a slot number that didn't exist
before calling btrfs_next_leaf(), as the leaf now has more keys than
it had before. So we must really process the returned leaf starting at
path->slots[0] always, as it isn't always 0, and the key at slot 0 can
have an offset much lower than our search offset/bytenr.
For example, consider the following scenario, where we have:
sums->bytenr: 40157184, sums->len: 16384, sums end: 40173568
four 4kb file data blocks with offsets 40157184, 40161280, 40165376, 40169472
Leaf N:
slot = 0 slot = btrfs_header_nritems() - 1
|-------------------------------------------------------------------|
| [(CSUM CSUM 39239680), size 8] ... [(CSUM CSUM 40116224), size 4] |
|-------------------------------------------------------------------|
Leaf N + 1:
slot = 0 slot = btrfs_header_nritems() - 1
|--------------------------------------------------------------------|
| [(CSUM CSUM 40161280), size 32] ... [((CSUM CSUM 40615936), size 8 |
|--------------------------------------------------------------------|
Because we are at the last slot of leaf N, we call btrfs_next_leaf() to
find the next highest key, which releases the current path and then searches
for that next key. However after releasing the path and before finding that
next key, the item at slot 0 of leaf N + 1 gets moved to leaf N, due to a call
to ctree.c:push_leaf_left() (via ctree.c:split_leaf()), and therefore
btrfs_next_leaf() will returns us a path again with leaf N but with the slot
pointing to its new last key (CSUM CSUM 40161280). This new version of leaf N
is then:
slot = 0 slot = btrfs_header_nritems() - 2 slot = btrfs_header_nritems() - 1
|----------------------------------------------------------------------------------------------------|
| [(CSUM CSUM 39239680), size 8] ... [(CSUM CSUM 40116224), size 4] [(CSUM CSUM 40161280), size 32] |
|----------------------------------------------------------------------------------------------------|
And incorrecly using slot 0, makes us set next_offset to 39239680 and we jump
into the "insert:" label, which will set tmp to:
tmp = min((sums->len - total_bytes) >> blocksize_bits,
(next_offset - file_key.offset) >> blocksize_bits) =
min((16384 - 0) >> 12, (39239680 - 40157184) >> 12) =
min(4, (u64)-917504 = 18446744073708634112 >> 12) = 4
and
ins_size = csum_size * tmp = 4 * 4 = 16 bytes.
In other words, we insert a new csum item in the tree with key
(CSUM_OBJECTID CSUM_KEY 40157184 = sums->bytenr) that contains the checksums
for all the data (4 blocks of 4096 bytes each = sums->len). Which is wrong,
because the item with key (CSUM CSUM 40161280) (the one that was moved from
leaf N + 1 to the end of leaf N) contains the old checksums of the last 12288
bytes of our data and won't get those old checksums removed.
So this leaves us 2 different checksums for 3 4kb blocks of data in the tree,
and breaks the logical rule:
Key_N+1.offset >= Key_N.offset + length_of_data_its_checksums_cover
An obvious bad effect of this is that a subsequent csum tree lookup to get
the checksum of any of the blocks with logical offset of 40161280, 40165376
or 40169472 (the last 3 4kb blocks of file data), will get the old checksums.
Cc: stable@vger.kernel.org
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
We've got bug reports that btrfs crashes when quota is enabled on
32bit kernel, typically with the Oops like below:
BUG: unable to handle kernel NULL pointer dereference at 00000004
IP: [<f9234590>] find_parent_nodes+0x360/0x1380 [btrfs]
*pde = 00000000
Oops: 0000 [#1] SMP
CPU: 0 PID: 151 Comm: kworker/u8:2 Tainted: G S W 3.15.2-1.gd43d97e-default #1
Workqueue: btrfs-qgroup-rescan normal_work_helper [btrfs]
task: f1478130 ti: f147c000 task.ti: f147c000
EIP: 0060:[<f9234590>] EFLAGS: 00010213 CPU: 0
EIP is at find_parent_nodes+0x360/0x1380 [btrfs]
EAX: f147dda8 EBX: f147ddb0 ECX: 00000011 EDX: 00000000
ESI: 00000000 EDI: f147dda4 EBP: f147ddf8 ESP: f147dd38
DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068
CR0: 8005003b CR2: 00000004 CR3: 00bf3000 CR4: 00000690
Stack:
00000000 00000000 f147dda4 00000050 00000001 00000000 00000001 00000050
00000001 00000000 d3059000 00000001 00000022 000000a8 00000000 00000000
00000000 000000a1 00000000 00000000 00000001 00000000 00000000 11800000
Call Trace:
[<f923564d>] __btrfs_find_all_roots+0x9d/0xf0 [btrfs]
[<f9237bb1>] btrfs_qgroup_rescan_worker+0x401/0x760 [btrfs]
[<f9206148>] normal_work_helper+0xc8/0x270 [btrfs]
[<c025e38b>] process_one_work+0x11b/0x390
[<c025eea1>] worker_thread+0x101/0x340
[<c026432b>] kthread+0x9b/0xb0
[<c0712a71>] ret_from_kernel_thread+0x21/0x30
[<c0264290>] kthread_create_on_node+0x110/0x110
This indicates a NULL corruption in prefs_delayed list. The further
investigation and bisection pointed that the call of ulist_add_merge()
results in the corruption.
ulist_add_merge() takes u64 as aux and writes a 64bit value into
old_aux. The callers of this function in backref.c, however, pass a
pointer of a pointer to old_aux. That is, the function overwrites
64bit value on 32bit pointer. This caused a NULL in the adjacent
variable, in this case, prefs_delayed.
Here is a quick attempt to band-aid over this: a new function,
ulist_add_merge_ptr() is introduced to pass/store properly a pointer
value instead of u64. There are still ugly void ** cast remaining
in the callers because void ** cannot be taken implicitly. But, it's
safer than explicit cast to u64, anyway.
Bugzilla: https://bugzilla.novell.com/show_bug.cgi?id=887046
Cc: <stable@vger.kernel.org> [v3.11+]
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Chris Mason <clm@fb.com>
When failing to allocate space for the whole compressed extent, we'll
fallback to uncompressed IO, but we've forgotten to redirty the pages
which belong to this compressed extent, and these 'clean' pages will
simply skip 'submit' part and go to endio directly, at last we got data
corruption as we write nothing.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Tested-By: Martin Steigerwald <martin@lichtvoll.de>
Signed-off-by: Chris Mason <clm@fb.com>
ulist_add() can return '1' on sucess, which qgroup_subtree_accounting()
doesn't take into account. As a result, that value can be bubbled up to
callers, causing an error to be printed. Fix this by only returning the
value of ulist_add() when it indicates an error.
Signed-off-by: Mark Fasheh <mfasheh@suse.de>
Signed-off-by: Chris Mason <clm@fb.com>
