In order to avoid this problem, we must serialize unlocked dio reads with
truncate. There are two approaches:
- use extent lock to protect the extent that we truncate
- use inode_dio_wait() to make sure the truncating task will wait for
the read DIO.
If we use the 1st one, we will meet the endless truncation problem due to
the nonlocked read DIO after we implement the nonlocked write DIO. It is
because we still need invoke inode_dio_wait() avoid the race between write
DIO and truncation. By that time, we have to introduce
btrfs_inode_{block, resume}_nolock_dio()
again. That is we have to implement this patch again, so I choose the 2nd
way to fix the problem.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Miao Xie [Thu, 7 Feb 2013 10:12:07 +0000 (10:12 +0000)]
Btrfs: fix deadlock due to unsubmitted
The deadlock problem happened when running fsstress(a test program in LTP).
Steps to reproduce:
# mkfs.btrfs -b 100M <partition>
# mount <partition> <mnt>
# <Path>/fsstress -p 3 -n 10000000 -d <mnt>
The reason is:
btrfs_direct_IO()
|->do_direct_IO()
|->get_page()
|->get_blocks()
| |->btrfs_delalloc_resereve_space()
| |->btrfs_add_ordered_extent() ------- Add a new ordered extent
|->dio_send_cur_page(page0) -------------- We didn't submit bio here
|->get_page()
|->get_blocks()
|->btrfs_delalloc_resereve_space()
|->flush_space()
|->btrfs_start_ordered_extent()
|->wait_event() ---------- Wait the completion of
the ordered extent that is
mentioned above
But because we didn't submit the bio that is mentioned above, the ordered
extent can not complete, we would wait for its completion forever.
There are two methods which can fix this deadlock problem:
1. submit the bio before we invoke get_blocks()
2. reserve the space before we do dio
Though the 1st is the simplest way, we need modify the code of VFS, and it
is likely to break contiguous requests, and introduce performance regression
for the other filesystems.
So we have to choose the 2nd way.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Cc: Josef Bacik <jbacik@fusionio.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Josef Bacik [Thu, 7 Feb 2013 21:27:28 +0000 (16:27 -0500)]
Btrfs: cleanup orphan reservation if truncate fails
I noticed we were getting lots of warnings with xfstest 83 because we have
reservations outstanding. This is because we moved the orphan add outside
of the truncate, but we don't actually cleanup our reservation if something
fails. This fixes the problem and I no longer see warnings. Thanks,
Josef Bacik [Thu, 7 Feb 2013 21:06:02 +0000 (16:06 -0500)]
Btrfs: steal from global reserve if we are cleaning up orphans
Sometimes xfstest 83 will fail to remount the scratch device because we've
gotten ourselves so full that we cannot cleanup the orphan items. In this
case check to see if we're doing the orphan cleanup and if we are allow us
to steal our reservation from the global block rsv. With this patch I've
not been able to reproduce the failed mount problem. Thanks,
Miao Xie [Thu, 7 Feb 2013 06:02:44 +0000 (06:02 +0000)]
Btrfs: fix memory leak of pending_snapshot->inherit
The argument "inherit" of btrfs_ioctl_snap_create_transid() was assigned
to NULL during we created the snapshots, so we didn't free it though we
called kfree() in the caller.
But since we are sure the snapshot creation is done after the function -
btrfs_ioctl_snap_create_transid() - completes, it is safe that we don't
assign the pointer "inherit" to NULL, and just free it in the caller of
btrfs_ioctl_snap_create_transid(). In this way, the code can become more
readable.
Reported-by: Alex Lyakas <alex.btrfs@zadarastorage.com> Cc: Arne Jansen <sensille@gmx.net> Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Miao Xie [Thu, 7 Feb 2013 06:01:35 +0000 (06:01 +0000)]
Btrfs: fix the race between bio and btrfs_stop_workers
open_ctree() need read the metadata to initialize the global information
of btrfs. But it may fail after it submit some bio, and then it will jump
to the error path. Unfortunately, it doesn't check if there are some bios
in flight, and just stop all the worker threads. As a result, when the
submitted bios end, they can not find any worker thread which can deal with
subsequent work, then oops happen.
kernel BUG at fs/btrfs/async-thread.c:605!
Fix this problem by invoking invalidate_inode_pages2() before we stop the
worker threads. This function will wait until the bio end because it need
lock the pages which are going to be invalidated, and if a page is under
disk read IO, it must be locked. invalidate_inode_pages2() need wait until
end bio handler to unlocked it.
Reported-and-Tested-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com> Signed-off-by: Eric Sandeen <sandeen@redhat.com> Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Mark Fasheh [Mon, 4 Feb 2013 20:54:57 +0000 (20:54 +0000)]
btrfs: add "no file data" flag to btrfs send ioctl
This patch adds the flag, BTRFS_SEND_FLAG_NO_FILE_DATA to the btrfs send
ioctl code. When this flag is set, the btrfs send code will never write file
data into the stream (thus also avoiding expensive reads of that data in the
first place). BTRFS_SEND_C_UPDATE_EXTENT commands will be sent (instead of
BTRFS_SEND_C_WRITE) with an offset, length pair indicating the extent in
question.
This patch does not affect the operation of BTRFS_SEND_C_CLONE commands -
they will continue to be sent when a search finds an appropriate extent to
clone from.
Signed-off-by: Mark Fasheh <mfasheh@suse.de> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Liu Bo [Mon, 4 Feb 2013 13:12:18 +0000 (13:12 +0000)]
Btrfs: extend the checksum item as much as possible
For write, we also reserve some space for COW blocks during updating
the checksum tree, and we calculate the number of blocks by checking
if the number of bytes outstanding that are going to need csums needs
one more block for csum.
When we add these checksum into the checksum tree, we use ordered sums
list.
Every ordered sum contains csums for each sector, and we'll first try
to look up an existing csum item,
a) if we don't yet have a proper csum item, then we need to insert one,
b) or if we find one but the csum item is not big enough, then we need
to extend it.
The point is we'll unlock the whole path and then insert or extend.
So others can hack in and update the tree.
Each insert or extend needs update the tree with COW on, and we may need
to insert/extend for many times.
That means what we've reserved for updating checksum tree is NOT enough
indeed.
The case is even more serious with having several write threads at the
same time, it can end up eating our reserved space quickly and starting
eating globle reserve pool instead.
I don't yet come up with a way to calculate the worse case for updating
csum, but extending the checksum item as much as possible can be helpful
in my test.
The idea behind is that it can reduce the times we insert/extend so that
it saves us precious reserved space.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Eric Sandeen [Thu, 31 Jan 2013 18:21:12 +0000 (18:21 +0000)]
btrfs: remove cache only arguments from defrag path
The entry point at the defrag ioctl always sets "cache only" to 0;
the codepaths haven't run for a long time as far as I can
tell. Chris says they're dead code, so remove them.
Signed-off-by: Eric Sandeen <sandeen@redhat.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Josef Bacik [Wed, 6 Feb 2013 21:55:41 +0000 (16:55 -0500)]
Btrfs: if we aren't committing just end the transaction if we error out
I hit a deadlock where transaction commit was waiting on num_writers to be
0. This happened because somebody came into btrfs_commit_transaction and
noticed we had aborted and it went to cleanup_transaction. This shouldn't
happen because cleanup_transaction is really to fixup a bad commit, it
doesn't do the normal trans handle cleanup things. So if we have an error
just do the normal btrfs_end_transaction dance and return. Once we are in
the actual commit path we can use cleanup_transaction and be good to go.
Thanks,
Josef Bacik [Wed, 6 Feb 2013 21:49:15 +0000 (16:49 -0500)]
Btrfs: handle errors in compression submission path
I noticed we would deadlock if we aborted a transaction while doing
compressed io. This is because we don't unlock our pages if something goes
horribly wrong. To fix this we need to make sure that we call
extent_clear_unlock_delalloc in order to unlock all the pages. If we have
to cow in the async submission thread we need to make sure to unlock our
locked_page as the cow error path will not unlock the locked page as it
depends on the caller to unlock that page. With this patch we no longer
deadlock on the page lock when we have an aborted transaction. Thanks,
Josef Bacik [Wed, 6 Feb 2013 18:53:19 +0000 (13:53 -0500)]
Btrfs: rework the overcommit logic to be based on the total size
People have been complaining about random ENOSPC errors that will clear up
after a umount or just a given amount of time. Chris was able to reproduce
this with stress.sh and lots of processes and so was I. Basically the
overcommit stuff would really let us get out of hand, in my tests I saw up
to 30 gigs of outstanding reservations with only 2 gigs total of metadata
space. This usually worked out fine but with so much outstanding
reservation the flushing stuff short circuits to make sure we don't hang
forever flushing when we really need ENOSPC. Plus we allocate chunks in
order to alleviate the pressure, but this doesn't actually help us since we
only use the non-allocated area in our over commit logic.
So instead of basing overcommit on the amount of non-allocated space,
instead just do it based on how much total space we have, and then limit it
to the non-allocated space in case we are short on space to spill over into.
This allows us to have the same performance as well as no longer giving
random ENOSPC. Thanks,
Josef Bacik [Fri, 1 Feb 2013 20:57:47 +0000 (15:57 -0500)]
Btrfs: account for orphan inodes properly during cleanup
Dave sent me a panic where we were doing the orphan cleanup and panic'ed
trying to release our reservation from the orphan block rsv. The reason for
this is because our orphan block rsv had been free'd out from underneath us
because the transaction commit found that there were no orphan inodes
according to its count and decided to free it. This is incorrect so make
sure we inc the orphan inodes count so the accounting is all done properly.
This would also cause the warning in the orphan commit code normally if you
had any orphans to cleanup as they would only decrement the orphan count so
you'd get a negative orphan count which could cause problems during runtime.
Thanks,
Josef Bacik [Thu, 31 Jan 2013 19:58:00 +0000 (14:58 -0500)]
Btrfs: unreserve space if our ordered extent fails to work
When a transaction aborts or there's an EIO on an ordered extent or any
error really we will not free up the space we reserved for this ordered
extent. This results in warnings from the block group cache cleanup in the
case of a transaction abort, or leaking space in the case of EIO on an
ordered extent. Fix this up by free'ing the reserved space if we have an
error at all trying to complete an ordered extent. Thanks,
Josef Bacik [Thu, 31 Jan 2013 19:30:08 +0000 (14:30 -0500)]
Btrfs: fix how we discard outstanding ordered extents on abort
When we abort we've been just free'ing up all the ordered extents and
hoping for the best. This results in lots of warnings from various places,
warnings from btrfs_destroy_inode() because it's ENOSPC accounting isn't
fixed. It will also screw up lots of pages who have been set private but
never get cleared because the ordered extents are never allowed to be
submitted. This patch fixes those warnings. Thanks,
Josef Bacik [Wed, 30 Jan 2013 21:03:59 +0000 (16:03 -0500)]
Btrfs: fix freeing delayed ref head while still holding its mutex
I hit this error when reproducing a bug that would end in a transaction
abort. We take the delayed ref head's mutex to keep anybody from processing
it while we're destroying it, but we fail to drop the mutex before we carry
on and free the damned thing. Fix this by doing the remove logic for the
head ourselves and unlock the mutex, that way we can avoid use after free's
or hung tasks waiting on that mutex to come back so they know the delayed
ref completed. Thanks,
Eric Sandeen [Thu, 31 Jan 2013 00:55:01 +0000 (00:55 +0000)]
btrfs: ensure we don't overrun devices_info[] in __btrfs_alloc_chunk
WARN_ON isn't enough, we need to stop the loop if for any reason
we would overrun the devices_info array.
I tried to track down the connection between the length of
the alloc_devices list and the rw_devices counter but
it wasn't immediately obvious, so be defensive about it.
Signed-off-by: Eric Sandeen <sandeen@redhat.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Eric Sandeen [Thu, 31 Jan 2013 00:54:55 +0000 (00:54 +0000)]
btrfs: handle null fs_info in btrfs_panic()
At least backref_tree_panic() can apparently pass
in a null fs_info, so handle that in __btrfs_panic
to get the message out on the console.
The btrfs_panic macro also uses fs_info, but that's
largely pointless; it's testing to see if
BTRFS_MOUNT_PANIC_ON_FATAL_ERROR is not set.
But if it *were* set, __btrfs_panic() would have,
well, paniced and we wouldn't be here, testing it!
So just BUG() at this point.
And since we only use fs_info once now, just use it
directly.
Signed-off-by: Eric Sandeen <sandeen@redhat.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Josef Bacik [Wed, 30 Jan 2013 22:02:51 +0000 (17:02 -0500)]
Btrfs: do not overcommit if we don't have enough space for global rsv
Because of how little we allocate chunks now we can get really tight on
metadata space before we will allocate a new chunk. This resulted in being
unable to add device extents when allocating a new metadata chunk as we did
not have enough space. This is because we were allowed to overcommit too
much metadata without actually making sure we had enough space to make
allocations. The idea behind overcommit is that we are allowed to say "sure
you can have that reservation" when most of the free space is occupied by
reservations, not actual allocations. But in this case where a majority of
the total space is in use by actual allocations we can screw ourselves by
not being able to make real allocations when it matters. So make sure we
have enough real space for our global reserve, and if not then don't allow
overcommitting. Thanks,
Reported-and-tested-by: Jim Schutt <jaschut@sandia.gov> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Josef Bacik [Thu, 31 Jan 2013 15:23:04 +0000 (10:23 -0500)]
Btrfs: remove extent mapping if we fail to add chunk
I got a double free error when unmounting a file system that failed to add a
chunk during its operation. This is because we will kfree the mapping that
we created but leave the extent_map in the em_tree for chunks. So to fix
this just remove the extent_map when we error out so we don't run into this
problem. Thanks,
Josef Bacik [Tue, 29 Jan 2013 20:03:37 +0000 (15:03 -0500)]
Btrfs: fix chunk allocation error handling
If we error out allocating a dev extent we will have already created the
block group and such which will cause problems since the allocator may have
tried to allocate out of the block group that no longer exists. This will
cause BUG_ON()'s in the bio submission path. This also makes a failure to
allocate a dev extent a non-abort error, we will just clean up the dev
extents we did allocate and exit. Now if we fail to delete the dev extents
we will abort since we can't have half of the dev extents hanging around,
but this will make us much less likely to abort. Thanks,
Miao Xie [Tue, 29 Jan 2013 10:14:48 +0000 (10:14 +0000)]
Btrfs: use bit operation for ->fs_state
There is no lock to protect fs_info->fs_state, it will introduce
some problems, such as the value may be covered by the other task
when several tasks modify it. For example:
Task0 - CPU0 Task1 - CPU1
mov %fs_state rax
or $0x1 rax
mov %fs_state rax
or $0x2 rax
mov rax %fs_state
mov rax %fs_state
The expected value is 3, but in fact, it is 2.
Though this problem doesn't happen now (because there is only one
flag currently), the code is error prone, if we add other flags,
the above problem will happen to a certainty.
Now we use bit operation for it to fix the above problem.
In this way, we can make the code more robust and be easy to
add new flags.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Miao Xie [Tue, 29 Jan 2013 10:13:12 +0000 (10:13 +0000)]
Btrfs: use seqlock to protect fs_info->avail_{data, metadata, system}_alloc_bits
There is no lock to protect
fs_info->avail_{data, metadata, system}_alloc_bits,
it may introduce some problem, such as the wrong profile
information, so we add a seqlock to protect them.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com> Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Miao Xie [Tue, 29 Jan 2013 10:11:59 +0000 (10:11 +0000)]
Btrfs: use the inode own lock to protect its delalloc_bytes
We need not use a global lock to protect the delalloc_bytes of the
inode, just use its own lock. In this way, we can reduce the lock
contention and ->delalloc_lock will just protect delalloc inode
list.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Miao Xie [Tue, 29 Jan 2013 10:10:51 +0000 (10:10 +0000)]
Btrfs: use percpu counter for fs_info->delalloc_bytes
fs_info->delalloc_bytes is accessed very frequently, so use percpu
counter instead of the u64 variant for it to reduce the lock
contention.
This patch also fixed the problem that we access the variant
without the lock protection.At worst, we would not flush the
delalloc inodes, and just return ENOSPC error when we still have
some free space in the fs.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Miao Xie [Tue, 29 Jan 2013 10:09:20 +0000 (10:09 +0000)]
Btrfs: use percpu counter for dirty metadata count
->dirty_metadata_bytes is accessed very frequently, so use percpu
counter instead of the u64 variant to reduce the contention of
the lock.
This patch also fixed the problem that we access it without
lock protection in __btrfs_btree_balance_dirty(), which may
cause we skip the dirty pages flush.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Miao Xie [Tue, 29 Jan 2013 10:07:33 +0000 (10:07 +0000)]
Btrfs: protect fs_info->alloc_start
fs_info->alloc_start is a 64bits variant, can be accessed by
multi-task, but it is not protected strictly, it can be changed
while we are accessing it. On 32bit machine, we will get wrong
value because we access it by two instructions.(In fact, it is
also possible that the same problem happens on the 64bit machine,
because the compiler may split the 64bit operation into two 32bit
operation.)
For example:
Assuming -> alloc_start is 0x0000 0000 0001 0000 at the beginning,
then we remount and set ->alloc_start to 0x0000 0100 0000 0000.
Task0 Task1
load high 32 bits
set high 32 bits
set low 32 bits
load low 32 bits
Task1 will get 0.
This patch fixes this problem by using two locks to protect it
fs_info->chunk_mutex
sb->s_umount
On the read side, we just need get one of these two locks, and on
the write side, we must lock all of them.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Miao Xie [Tue, 29 Jan 2013 10:05:05 +0000 (10:05 +0000)]
Btrfs: add a comment for fs_info->max_inline
Though ->max_inline is a 64bit variant, and may be accessed by
multi-task, but it is just suggestive number, so we needn't add
anything to protect fs_info->max_inline, just add a comment to
explain wny we don't use a lock to protect it.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Btrfs: move fs/btrfs/ioctl.h to include/uapi/linux/btrfs.h
The header file will then be installed under /usr/include/linux so that
userspace applications can refer to Btrfs ioctls by name and use the same
structs used internally in the kernel.
Signed-off-by: Filipe Brandenburger <filbranden@google.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Miao Xie [Tue, 22 Jan 2013 10:52:04 +0000 (10:52 +0000)]
Btrfs: don't traverse the ordered operation list repeatedly
btrfs_run_ordered_operations() needn't traverse the ordered operation list
repeatedly, it is because the transaction commiter will invoke it again when
there is no other writer in this transaction, it can ensure that no one can
add new objects into the ordered operation list.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Miao Xie [Tue, 22 Jan 2013 10:50:35 +0000 (10:50 +0000)]
Btrfs: traverse and flush the delalloc inodes once
btrfs_start_delalloc_inodes() needn't traverse and flush the delalloc inodes
repeatedly. It is because we can regard the data that the users write after
we start delalloc inodes flush as the one which is after the delalloc inodes
flush is done, and we can flush it next time.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Miao Xie [Thu, 17 Jan 2013 05:38:51 +0000 (05:38 +0000)]
Btrfs: make raid attr array more readable
The current code of raid attr arry is hard to understand and it is easy to
introduce some problem if we modify the array. So I changed it and made it
more readable.
Cc: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Liu Bo [Thu, 27 Dec 2012 09:01:17 +0000 (09:01 +0000)]
Btrfs: remove deprecated comments
commit d53ba47484ed6245e640ee4bfe9d21e9bfc15765
(Btrfs: use commit root when loading free space cache) has remove
the deadlock check, and the related comments can be removed as well.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com> Reviewed-by: David Sterba <dsterba@suse.cz> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Josef Bacik [Tue, 18 Dec 2012 14:16:16 +0000 (09:16 -0500)]
Btrfs: don't re-enter when allocating a chunk
If we start running low on metadata space we will try to allocate a chunk,
which could then try to allocate a chunk to add the device entry. The thing
is we allocate a chunk before we try really hard to make the allocation, so
we should be able to find space for the device entry. Add a flag to the
trans handle so we know we're currently allocating a chunk so we can just
bail out if we try to allocate another chunk. Thanks,
Josef Bacik [Fri, 12 Oct 2012 19:27:49 +0000 (15:27 -0400)]
Btrfs: wait on ordered extents at the last possible moment
Since we don't actually copy the extent information from the source tree in
the fast case we don't need to wait for ordered io to be completed in order
to fsync, we just need to wait for the io to be completed. So when we're
logging our file just attach all of the ordered extents to the log, and then
when the log syncs just wait for IO_DONE on the ordered extents and then
write the super. Thanks,
Miao Xie [Thu, 20 Dec 2012 11:19:09 +0000 (11:19 +0000)]
Btrfs: flush all dirty inodes if writeback can not start
We may try to flush some dirty pages when there is no enough space to reserve.
But it is possible that this operation fails, in order to get enough space to
reserve successfully, we will sync all the delalloc file. This operation is
safe, we needn't worry about the case that the filesystem goes from r/w to r/o.
because the filesystem should guarantee all the dirty pages have been written
into the disk after it becomes readonly, so the sync operation will do nothing
if the filesystem is already readonly. Though it may waste lots of time,
as a corner case, we needn't care.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Miao Xie [Wed, 19 Dec 2012 08:10:10 +0000 (08:10 +0000)]
Btrfs: make delayed ref lock logic more readable
Locking and unlocking delayed ref mutex are in the different functions,
and the name of lock functions is not uniform, so the readability is not
so good, this patch optimizes the lock logic and makes it more readable.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Miao Xie [Wed, 19 Dec 2012 06:59:51 +0000 (06:59 +0000)]
Btrfs: fix lots of orphan inodes when the space is not enough
We're running into having 50-100 orphans left over with xfstests 83
because of ENOSPC when trying to start the transaction for the inode update.
But in fact, it makes no sense in updating the inode for the new size while
we're deleting the stupid thing. This patch fixes this problem.
Reported-by: Josef Bacik <jbacik@fusionio.com> Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
David Sterba [Fri, 15 Feb 2013 18:31:02 +0000 (11:31 -0700)]
btrfs: access superblock via pagecache in scan_one_device
btrfs_scan_one_device is calling set_blocksize() which can race
with a concurrent process making dirty page cache pages. It can end up
dropping dirty page cache pages on the floor, which isn't very nice when
someone is just running btrfs dev scan to find filesystems on the
box.
Now that udev is registering btrfs devices as it discovers them, we can
actually end up racing with our own mkfs program too. When this
happens, we drop some of the important blocks written by mkfs.
This commit changes scan_one_device to read the super out of the page
cache instead of trying to use bread. This way we don't have to care
about the blocksize of the device.
This also drops the invalidate_bdev() call. It wasn't very polite to
invalidate during the scan either. mkfs is putting the super into the
page cache, there's no reason to invalidate at this point.
Signed-off-by: David Sterba <dsterba@suse.cz> Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Arne Jansen [Wed, 13 Feb 2013 11:20:01 +0000 (04:20 -0700)]
Btrfs: fix crash in log replay with qgroups enabled
When replaying a log tree with qgroups enabled, tree_mod_log_rewind does a
sanity-check of the number of items against the maximum possible number.
It calculates that number with the nodesize of fs_root. Unfortunately
fs_root is not yet set at this stage. So instead use the nodesize from
tree_root, which is already initialized.
Signed-off-by: Arne Jansen <sensille@gmx.net> Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Chris Mason [Wed, 6 Feb 2013 17:06:02 +0000 (12:06 -0500)]
Btrfs: move d_instantiate outside the transaction during mksubvol
Dave Sterba triggered a lockdep complaint about lock ordering
between the sb_internal lock and the cleaner semaphore.
btrfs_lookup_dentry() checks for orphans if we're looking up
the inode for a subvolume, and subvolume creation is triggering
the lookup with a transaction running.
This commit moves the d_instantiate after the transaction closes.
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Jan Schmidt [Mon, 28 Jan 2013 06:26:00 +0000 (23:26 -0700)]
Btrfs: fix EDQUOT handling in btrfs_delalloc_reserve_metadata
When btrfs_qgroup_reserve returned a failure, we were missing a counter
operation for BTRFS_I(inode)->outstanding_extents++, leading to warning
messages about outstanding extents and space_info->bytes_may_use != 0.
Additionally, the error handling code didn't take into account that we
dropped the inode lock which might require more cleanup.
Luckily, all the cleanup code we need is already there and can be shared
with reserve_metadata_bytes, which is exactly what this patch does.
Reported-by: Lev Vainblat <lev@zadarastorage.com> Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net> Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Josef Bacik [Wed, 30 Jan 2013 19:31:31 +0000 (14:31 -0500)]
Btrfs: fix possible stale data exposure
We specifically do not update the disk i_size if there are ordered extents
outstanding for any area between the current disk_i_size and our ordered
extent so that we do not expose stale data. The problem is the check we
have only checks if the ordered extent starts at or after the current
disk_i_size, which doesn't take into account an ordered extent that starts
before the current disk_i_size and ends past the disk_i_size. Fix this by
checking if the extent ends past the disk_i_size. Thanks,
Josef Bacik [Wed, 30 Jan 2013 19:17:31 +0000 (14:17 -0500)]
Btrfs: fix missing i_size update
If we have an ordered extent before the ordered extent we are currently
completing that is after the current disk_i_size we will put our i_size
update into that ordered extent so that we do not expose stale data. The
problem is that if our disk i_size is updated past the previous ordered
extent we won't update the i_size with the pending i_size update. So check
the pending i_size update and if its above the current disk i_size we need
to go ahead and try to update. Thanks,
Liu Bo [Tue, 29 Jan 2013 03:22:10 +0000 (03:22 +0000)]
Btrfs: fix race between snapshot deletion and getting inode
While running snapshot testscript created by Mitch and David,
the race between autodefrag and snapshot deletion can lead to
corruption of dead_root list so that we can get crash on
btrfs_clean_old_snapshots().
And besides autodefrag, scrub also does the same thing, ie. read
root first and get inode.
Here is the story(take autodefrag as an example):
(1) when we delete a snapshot or subvolume, it will set its root's
refs to zero and do a iput() on its own inode, and if this inode happens
to be the only active in-meory one in root's inode rbtree, it will add
itself to the global dead_roots list for later cleanup.
(2) after (1), the autodefrag thread may read another inode for defrag
and the inode is just in the deleted snapshot/subvolume, but all of these
are without checking if the root is still valid(refs > 0). So the end up
result is adding the deleted snapshot/subvolume's root to the global
dead_roots list AGAIN.
Fortunately, we already have a srcu lock to avoid the race, ie. subvol_srcu.
So all we need to do is to take the lock to protect 'read root and get inode',
since we synchronize to wait for the rcu grace period before adding something
to the global dead_roots list.
Reported-by: Mitch Harder <mitch.harder@sabayonlinux.org> Signed-off-by: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Josef Bacik [Mon, 28 Jan 2013 14:45:20 +0000 (09:45 -0500)]
Btrfs: do not merge logged extents if we've removed them from the tree
You can run into this problem where if somebody is fsyncing and writing out
the existing extents you will have removed the extent map from the em tree,
but it's still valid for the current fsync so we go ahead and write it. The
problem is we unconditionally try to merge it back into the em tree, but if
we've removed it from the em tree that will cause use after free problems.
Fix this to only merge if we are still a part of the tree. Thanks,
Eric Sandeen [Thu, 31 Jan 2013 00:55:02 +0000 (00:55 +0000)]
btrfs: don't try to notify udev about missing devices
If we remove a missing device, bdev is null, and if we
send that off to btrfs_kobject_uevent we'll panic.
Signed-off-by: Eric Sandeen <sandeen@redhat.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com> Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Miao Xie [Tue, 22 Jan 2013 10:49:00 +0000 (10:49 +0000)]
Btrfs: fix repeated delalloc work allocation
btrfs_start_delalloc_inodes() locks the delalloc_inodes list, fetches the
first inode, unlocks the list, triggers btrfs_alloc_delalloc_work/
btrfs_queue_worker for this inode, and then it locks the list, checks the
head of the list again. But because we don't delete the first inode that it
deals with before, it will fetch the same inode. As a result, this function
allocates a huge amount of btrfs_delalloc_work structures, and OOM happens.
Fix this problem by splice this delalloc list.
Reported-by: Alex Lyakas <alex.btrfs@zadarastorage.com> Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Miao Xie [Wed, 16 Jan 2013 11:27:17 +0000 (11:27 +0000)]
Btrfs: fix wrong max device number for single profile
The max device number of single profile is 1, not 0 (0 means 'as many as
possible'). Fix it.
Cc: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Reviewed-by: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Miao Xie [Tue, 15 Jan 2013 06:29:12 +0000 (06:29 +0000)]
Btrfs: fix missed transaction->aborted check
First, though the current transaction->aborted check can stop the commit early
and avoid unnecessary operations, it is too early, and some transaction handles
don't end, those handles may set transaction->aborted after the check.
Second, when we commit the transaction, we will wake up some worker threads to
flush the space cache and inode cache. Those threads also allocate some transaction
handles and may set transaction->aborted if some serious error happens.
So we need more check for ->aborted when committing the transaction. Fix it.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Miao Xie [Tue, 15 Jan 2013 06:27:25 +0000 (06:27 +0000)]
Btrfs: Add ACCESS_ONCE() to transaction->abort accesses
We may access and update transaction->aborted on the different CPUs without
lock, so we need ACCESS_ONCE() wrapper to prevent the compiler from creating
unsolicited accesses and make sure we can get the right value.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Josef Bacik [Tue, 22 Jan 2013 20:43:09 +0000 (15:43 -0500)]
Btrfs: put csums on the right ordered extent
I noticed a WARN_ON going off when adding csums because we were going over
the amount of csum bytes that should have been allowed for an ordered
extent. This is a leftover from when we used to hold the csums privately
for direct io, but now we use the normal ordered sum stuff so we need to
make sure and check if we've moved on to another extent so that the csums
are added to the right extent. Without this we could end up with csums for
bytenrs that don't have extents to cover them yet. Thanks,
Liu Bo [Sun, 6 Jan 2013 03:38:22 +0000 (03:38 +0000)]
Btrfs: use right range to find checksum for compressed extents
For compressed extents, the range of checksum is covered by disk length,
and the disk length is different with ram length, so we need to use disk
length instead to get us the right checksum.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Josef Bacik [Tue, 18 Dec 2012 16:39:19 +0000 (11:39 -0500)]
Btrfs: fix panic when recovering tree log
A user reported a BUG_ON(ret) that occured during tree log replay. Ret was
-EAGAIN, so what I think happened is that we removed an extent that covered
a bitmap entry and an extent entry. We remove the part from the bitmap and
return -EAGAIN and then search for the next piece we want to remove, which
happens to be an entire extent entry, so we just free the sucker and return.
The problem is ret is still set to -EAGAIN so we trip the BUG_ON(). The
user used btrfs-zero-log so I'm not 100% sure this is what happened so I've
added a WARN_ON() to catch the other possibility. Thanks,
Reported-by: Jan Steffens <jan.steffens@gmail.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Josef Bacik [Thu, 24 Jan 2013 17:02:07 +0000 (12:02 -0500)]
Btrfs: do not allow logged extents to be merged or removed
We drop the extent map tree lock while we're logging extents, so somebody
could come in and merge another extent into this one and screw up our
logging, or they could even remove us from the list which would keep us from
logging the extent or freeing our ref on it, so we need to make sure to not
clear LOGGING until after the extent is logged, and then we can merge it to
adjacent extents. Thanks,
Ilya Dryomov [Mon, 21 Jan 2013 13:15:56 +0000 (15:15 +0200)]
Btrfs: fix a regression in balance usage filter
Commit 3fed40cc ("Btrfs: cleanup duplicated division functions"), which
was merged into 3.8-rc1, has introduced a regression by removing logic
that was guarding us against bad user input. Bring it back.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com> Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Arne Jansen [Thu, 17 Jan 2013 08:22:09 +0000 (01:22 -0700)]
Btrfs: prevent qgroup destroy when there are still relations
Currently you can just destroy a qgroup even though it is in use by other qgroups
or has qgroups assigned to it. This patch prevents destruction of qgroups unless
they are completely unused. Otherwise destroy will return EBUSY.
Reported-by: Eric Hopper <hopper@omnifarious.org> Signed-off-by: Arne Jansen <sensille@gmx.net> Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Arne Jansen [Thu, 17 Jan 2013 08:22:08 +0000 (01:22 -0700)]
Btrfs: ignore orphan qgroup relations
If a qgroup that has still assignments is deleted by the user, the corresponding
relations are left in the tree. This leads to an unmountable filesystem.
With this patch, those relations are simple ignored.
Reported-by: Eric Hopper <hopper@omnifarious.org> Signed-off-by: Arne Jansen <sensille@gmx.net> Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Ilya Dryomov [Sun, 20 Jan 2013 13:57:57 +0000 (15:57 +0200)]
Btrfs: fix "mutually exclusive op is running" error code
The error code that is returned in response to starting a mutually
exclusive operation when there is one already running got silently
changed from EINVAL to EINPROGRESS by 5ac00add. Returning EINPROGRESS
to, say, add_dev, when rm_dev is running is misleading. Furthermore,
the operation itself may want to use EINPROGRESS for other purposes.
Ilya Dryomov [Sun, 20 Jan 2013 13:57:57 +0000 (15:57 +0200)]
Btrfs: bring back balance pause/resume logic
Balance pause/resume logic got broken by 5ac00add (went in into 3.8-rc1
as part of dev-replace merge). Offending commit took a stab at making
mutually exclusive volume operations (add_dev, rm_dev, resize, balance,
replace_dev) not block behind volume_mutex if another such operation is
in progress and instead return an error right away. Balancing front-end
relied on the blocking behaviour, so the fix is ugly, but short of a
complete rework, it's the best we can do.
Reported-by: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Eric Sandeen [Sat, 12 Jan 2013 02:57:22 +0000 (02:57 +0000)]
btrfs: update timestamps on truncate()
truncate() vs. ftruncate() differ in the VFS; truncate()
doesn't set (ATTR_CTIME | ATTR_MTIME), and it's up to the
fs to do the timestamp updates if the size changes.
Signed-off-by: Eric Sandeen <sandeen@redhat.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com>
I have no idea if that -EEXIST is surprising, or not. Regardless, this
error handling should be cleaned up to handle other reasonable errors
(ENOMEM, EIO; whatever).
This seemed to be the only buggy freeing of the relatively rare IS_ERR
em so I opted to fix the caller rather than teach free_extent_map() to
use IS_ERR_OR_NULL().
Signed-off-by: Zach Brown <zab@redhat.com> Reviewed-by: Eric Sandeen <sandeen@redhat.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Liu Bo [Mon, 7 Jan 2013 10:10:12 +0000 (10:10 +0000)]
Btrfs: fix a bug when llseek for delalloc bytes behind prealloc extents
xfstests case 285 complains.
It it because btrfs did not try to find unwritten delalloc
bytes(only dirty pages, not yet writeback) behind prealloc
extents, it ends up finding nothing while we're with SEEK_DATA.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Liu Bo [Thu, 27 Dec 2012 09:01:24 +0000 (09:01 +0000)]
Btrfs: let allocation start from the right raid type
This'd avoid us empty looping.
Say we have only one disk and the metadata raid type will be defaultly DUP,
and we do not need to start from index=0(RAID10) and get over two empty
loops to index=2(DUP).
Signed-off-by: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Josef Bacik [Mon, 7 Jan 2013 22:03:21 +0000 (17:03 -0500)]
Btrfs: add orphan before truncating pagecache
Running xfstests 83 in a loop would sometimes fail the fsck. This happens
because if we invalidate a page that already has an ordered extent setup for
it we will complete the ordered extent ourselves, assuming that the truncate
will clean everything up. The problem with this is there is plenty of time
for the truncate to fail after we've done this work. So to fix this we need
to add the orphan item first to make sure the cleanup gets done properly,
and then we can truncate the pagecache and all that stuff and be safe. This
fixes the btrfsck failures I was seeing while running 83 in a loop. Thanks,
projects / mirror_ubuntu-eoan-kernel.git / log