Replace the fs_info->cache_workers with the newly created
btrfs_workqueue.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Tested-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Replace the fs_info->rmw_workers with the newly created
btrfs_workqueue.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Tested-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Replace the fs_info->endio_* workqueues with the newly created
btrfs_workqueue.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Tested-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Replace the fs_info->submit_workers with the newly created
btrfs_workqueue.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Tested-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Much like the fs_info->workers, replace the fs_info->submit_workers
use the same btrfs_workqueue.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Tested-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Much like the fs_info->workers, replace the fs_info->delalloc_workers
use the same btrfs_workqueue.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Tested-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Use the newly created btrfs_workqueue_struct to replace the original
fs_info->workers
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Tested-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
We might commit the log sub-transaction which didn't contain the metadata we
logged. It was because we didn't record the log transid and just select
the current log sub-transaction to commit, but the right one might be
committed by the other task already. Actually, we needn't do anything
and it is safe that we go back directly in this case.
This patch improves the log sync by the above idea. We record the transid
of the log sub-transaction in which we log the metadata, and the transid
of the log sub-transaction we have committed. If the committed transid
is >= the transid we record when logging the metadata, we just go back.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
It is possible that many tasks sync the log tree at the same time, but
only one task can do the sync work, the others will wait for it. But those
wait tasks didn't get the result of the log sync, and returned 0 when they
ended the wait. It caused those tasks skipped the error handle, and the
serious problem was they told the users the file sync succeeded but in
fact they failed.
This patch fixes this problem by introducing a log context structure,
we insert it into the a global list. When the sync fails, we will set
the error number of every log context in the list, then the waiting tasks
get the error number of the log context and handle the error if need.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
I got an error on v3.13:
BTRFS error (device sdf1) in write_all_supers:3378: errno=-5 IO failure (errors while submitting device barriers.)
how to reproduce:
> mkfs.btrfs -f -d raid1 /dev/sdf1 /dev/sdf2
> wipefs -a /dev/sdf2
> mount -o degraded /dev/sdf1 /mnt
> btrfs balance start -f -sconvert=single -mconvert=single -dconvert=single /mnt
The reason of the error is that barrier_all_devices() failed to submit
barrier to the missing device. However it is clear that we cannot do
anything on missing device, and also it is not necessary to care chunks
on the missing device.
This patch stops sending/waiting barrier if device is missing.
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Josef Bacik <jbacik@fb.com>
During device replace test, we hit a null pointer deference (It was very easy
to reproduce it by running xfstests' btrfs/011 on the devices with the virtio
scsi driver). There were two bugs that caused this problem:
- We might allocate new chunks on the replaced device after we updated
the mapping tree. And we forgot to replace the source device in those
mapping of the new chunks.
- We might get the mapping information which including the source device
before the mapping information update. And then submit the bio which was
based on that mapping information after we freed the source device.
For the first bug, we can fix it by doing mapping tree update and source
device remove in the same context of the chunk mutex. The chunk mutex is
used to protect the allocable device list, the above method can avoid
the new chunk allocation, and after we remove the source device, all
the new chunks will be allocated on the new device. So it can fix
the first bug.
For the second bug, we need make sure all flighting bios are finished and
no new bios are produced during we are removing the source device. To fix
this problem, we introduced a global @bio_counter, we not only inc/dec
@bio_counter outsize of map_blocks, but also inc it before submitting bio
and dec @bio_counter when ending bios.
Since Raid56 is a little different and device replace dosen't support raid56
yet, it is not addressed in the patch and I add comments to make sure we will
fix it in the future.
Reported-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Given now we have 2 spinlock for management of delayed refs,
CONFIG_DEBUG_SPINLOCK=y helped me find this,
[ 4723.413809] BUG: spinlock wrong CPU on CPU#1, btrfs-transacti/2258
[ 4723.414882] lock: 0xffff880048377670, .magic: dead4ead, .owner: btrfs-transacti/2258, .owner_cpu: 2
[ 4723.417146] CPU: 1 PID: 2258 Comm: btrfs-transacti Tainted: G W O 3.12.0+ #4
[ 4723.421321] Call Trace:
[ 4723.421872] [<ffffffff81680fe7>] dump_stack+0x54/0x74
[ 4723.422753] [<ffffffff81681093>] spin_dump+0x8c/0x91
[ 4723.424979] [<ffffffff816810b9>] spin_bug+0x21/0x26
[ 4723.425846] [<ffffffff81323956>] do_raw_spin_unlock+0x66/0x90
[ 4723.434424] [<ffffffff81689bf7>] _raw_spin_unlock+0x27/0x40
[ 4723.438747] [<ffffffffa015da9e>] btrfs_cleanup_one_transaction+0x35e/0x710 [btrfs]
[ 4723.443321] [<ffffffffa015df54>] btrfs_cleanup_transaction+0x104/0x570 [btrfs]
[ 4723.444692] [<ffffffff810c1b5d>] ? trace_hardirqs_on_caller+0xfd/0x1c0
[ 4723.450336] [<ffffffff810c1c2d>] ? trace_hardirqs_on+0xd/0x10
[ 4723.451332] [<ffffffffa015e5ee>] transaction_kthread+0x22e/0x270 [btrfs]
[ 4723.452543] [<ffffffffa015e3c0>] ? btrfs_cleanup_transaction+0x570/0x570 [btrfs]
[ 4723.457833] [<ffffffff81079efa>] kthread+0xea/0xf0
[ 4723.458990] [<ffffffff81079e10>] ? kthread_create_on_node+0x140/0x140
[ 4723.460133] [<ffffffff81692aac>] ret_from_fork+0x7c/0xb0
[ 4723.460865] [<ffffffff81079e10>] ? kthread_create_on_node+0x140/0x140
[ 4723.496521] ------------[ cut here ]------------
----------------------------------------------------------------------
The reason is that we get to call cond_resched_lock(&head_ref->lock) while
still holding @delayed_refs->lock.
So it's different with __btrfs_run_delayed_refs(), where we do drop-acquire
dance before and after actually processing delayed refs.
Here we don't drop the lock, others are not able to add new delayed refs to
head_ref, so cond_resched_lock(&head_ref->lock) is not necessary here.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
After the commit titled "Btrfs: fix btrfs boot when compiled as built-in",
LIBCRC32C requirement was removed from btrfs' Kconfig. This made it not
possible to build a kernel with btrfs enabled (either as module or built-in)
if libcrc32c is not enabled as well. So just replace all uses of libcrc32c
with the equivalent function in btrfs hash.h - btrfs_crc32c.
Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
When transaction is aborted, we fail to commit transaction, instead we do
cleanup work. After that when we umount btrfs, we get to free fs roots' log
trees respectively, but that happens after we unpin extents, so those extents
pinned by freeing log trees will remain in memory and lead to the leak.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
Add noinode_cache mount option for btrfs.
Since inode map cache involves all the btrfs_find_free_ino/return_ino
things and if just trigger the mount_opt,
an inode number get from inode map cache will not returned to inode map
cache.
To keep the find and return inode both in the same behavior,
a new bit in mount_opt, CHANGE_INODE_CACHE, is introduced for this idea.
CHANGE_INODE_CACHE is set/cleared in remounting, and the original
INODE_MAP_CACHE is set/cleared according to CHANGE_INODE_CACHE after a
success transaction.
Since find/return inode is all done between btrfs_start_transaction and
btrfs_commit_transaction, this will keep consistent behavior.
Also noinode_cache mount option will not stop the caching_kthread.
Cc: David Sterba <dsterba@suse.cz>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
On one of our gluster clusters we noticed some pretty big lag spikes. This
turned out to be because our transaction commit was taking like 3 minutes to
complete. This is because we have like 30 gigs of metadata, so our global
reserve would end up being the max which is like 512 mb. So our throttling code
would allow a ridiculous amount of delayed refs to build up and then they'd all
get run at transaction commit time, and for a cold mounted file system that
could take up to 3 minutes to run. So fix the throttling to be based on both
the size of the global reserve and how long it takes us to run delayed refs.
This patch tracks the time it takes to run delayed refs and then only allows 1
seconds worth of outstanding delayed refs at a time. This way it will auto-tune
itself from cold cache up to when everything is in memory and it no longer has
to go to disk. This makes our transaction commits take much less time to run.
Thanks,
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
Currently we have two rb-trees, one for delayed ref heads and one for all of the
delayed refs, including the delayed ref heads. When we process the delayed refs
we have to hold onto the delayed ref lock for all of the selecting and merging
and such, which results in quite a bit of lock contention. This was solved by
having a waitqueue and only one flusher at a time, however this hurts if we get
a lot of delayed refs queued up.
So instead just have an rb tree for the delayed ref heads, and then attach the
delayed ref updates to an rb tree that is per delayed ref head. Then we only
need to take the delayed ref lock when adding new delayed refs and when
selecting a delayed ref head to process, all the rest of the time we deal with a
per delayed ref head lock which will be much less contentious.
The locking rules for this get a little more complicated since we have to lock
up to 3 things to properly process delayed refs, but I will address that problem
later. For now this passes all of xfstests and my overnight stress tests.
Thanks,
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
We only intent to fua the first superblock in every device from
comments, fix it.
Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
Convert all applicable cases of printk and pr_* to the btrfs_* macros.
Fix all uses of the BTRFS prefix.
Signed-off-by: Frank Holton <fholton@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
I need to create a fake tree to test qgroups and I don't want to have to setup a
fake btree_inode. The fact is we only use the radix tree for the fs_info, so
everybody else who allocates an extent_io_tree is just wasting the space anyway.
This patch moves the radix tree and its lock into btrfs_fs_info so there is less
stuff I have to fake to do qgroup sanity tests. Thanks,
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
This is the third step in bootstrapping the btrfs_find_item interface.
The function find_orphan_item(), in orphan.c, is similar to the two
functions already replaced by the new interface. It uses two parameters,
which are already present in the interface, and is nearly identical to
the function brought in in the previous patch.
Replace the two calls to find_orphan_item() with calls to
btrfs_find_item(), with the defined objectid and type that was used
internally by find_orphan_item(), a null path, and a null key. Add a
test for a null path to btrfs_find_item, and if it passes, allocate and
free the path. Finally, remove find_orphan_item().
Signed-off-by: Kelley Nielsen <kelleynnn@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <clm@fb.com>
Remove unused variables:
* tree from csum_dirty_buffer,
* tree from btree_readpage_end_io_hook,
* tree from btree_writepages,
* bytenr from btrfs_create_tree,
* fs_info from end_workqueue_fn.
Signed-off-by: Valentina Giusti <valentina.giusti@microon.de>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <clm@fb.com>
This patch adds per-super attributes to sysfs.
It doesn't publish any attributes yet, but does the proper lifetime
handling as well as the basic infrastructure to add new attributes.
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <clm@fb.com>
The way how we process delayed refs is
1) get a bunch of head refs,
2) pick up one head ref,
3) go one node back for any delayed ref updates.
The head ref is also linked in the same rbtree as the delayed ref is,
so in 1) stage, we have to walk one by one including not only head refs, but
delayed refs.
When we have a great number of delayed refs pending to process,
this'll cost time a lot.
Here we introduce a head ref specific rbtree, it only has head refs, so troubles
go away.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <clm@fb.com>
The 'git blame' history shows that, the old transaction commit code has to do
twice to ensure roots are updated and we have to flush metadata and super block
manually, however, right now all of these can be handled well inside
the transaction commit code without extra efforts.
And the error handling part remains same with the current code, -- 'return to
caller once we get error'.
This saves us a transaction commit and a flush of super block, which are both
heavy operations according to ftrace output analysis.
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
The function write_ctree_super() in disk-io.c uses variable ret to return
the result of function write_all_supers(). Since, this variable serves
no purpose, hence the patch removes it and returns the call of the
called function.
Reviewed-by: Zach Brown <zab@redhat.com>
Signed-off-by: Rashika Kheria <rashika.kheria@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Use WARN_ON()'s return value in place of WARN_ON(1) for cleaner source
code that outputs a more descriptive warnings. Also fix the styling
warning of redundant braces that came up as a result of this fix.
Signed-off-by: Dulshani Gunawardhana <dulshani.gunawardhana89@gmail.com>
Reviewed-by: Zach Brown <zab@redhat.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
The function free_root_pointers() in disk-io.h contains redundant code.
Therefore, this patch adds a helper function free_root_extent_buffers()
to free_root_pointers() to eliminate redundancy.
Reviewed-by: Zach Brown <zab@redhat.com>
Signed-off-by: Rashika Kheria <rashika.kheria@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Originally, we introduced scrub_super_lock to synchronize
tree log code with scrubbing super.
However we can replace scrub_super_lock with device_list_mutex,
because writing super will hold this mutex, this will reduce an extra
lock holding when writing supers in sync log code.
Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
fs/btrfs/compat.h only contained trivial macro wrappers of drop_nlink()
and inc_nlink(). This doesn't belong in mainline.
Signed-off-by: Zach Brown <zab@redhat.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
alloc_extent_buffer() uses radix_tree_lookup() when radix_tree_insert()
fails with EEXIST. That part of the code is very similar to the code in
find_extent_buffer(). This patch replaces radix_tree_lookup() and
surrounding code in alloc_extent_buffer() with find_extent_buffer().
Note that radix_tree_lookup() does not need to be protected by
tree->buffer_lock. It is protected by eb->refs.
While at it, this patch
- changes the other usage of radix_tree_lookup() in alloc_extent_buffer()
with find_extent_buffer() to reduce redundancy.
- removes the unused argument 'len' to find_extent_buffer().
Signed-Off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Reviewed-by: Zach Brown <zab@redhat.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Stefan was hitting a panic in the async worker stuff because we had outstanding
read bios while we were stopping the worker threads. You could reproduce this
easily if you mount -o nospace_cache and ran generic/273. This is because the
caching thread stuff is still going and we were stopping all the worker threads.
We need to stop the workers after this work is done, and the free block groups
code will wait for all the caching threads to stop first so we don't run into
this problem. With this patch we no longer panic. Thanks,
Cc: stable@vger.kernel.org
Reported-by: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
If we abort a transaction we will do the tree log cleanup at unmount, but this
happens after we free up the block groups. This makes all the leak detection
warnings go off because we think we've leaked space but in reality we just
haven't cleaned it up yet. So instead do the block group cleanup stuff after
free'ing the fs roots so we don't get these warnings. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
The transactions should be cleaning up their reservations on failure, this just
causes us to have warnings on unmount because we go negative by free'ing
reservations that have already been free'ed. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Currently the hash value used for adding an inode to the VFS's inode
hash table consists of the plain inode number, which is a 64 bits
integer. This results in hash table buckets (hlist_head lists) with
too many elements for at least 2 important scenarios:
1) When we have many subvolumes. Each subvolume has its own btree
where its files and directories are added to, and each has its
own objectid (inode number) namespace. This means that if we have
N subvolumes, and all have inode number X associated to a file or
directory, the corresponding inodes all map to the same hash table
entry, resulting in a bucket (hlist_head list) with N elements;
2) On 32 bits machines. Th VFS hash values are unsigned longs, which
are 32 bits wide on 32 bits machines, and the inode (objectid)
numbers are 64 bits unsigned integers. We simply cast the inode
numbers to hash values, which means that for all inodes with the
same 32 bits lower half, the same hash bucket is used for all of
them. For example, all inodes with a number (objectid) between
0x0000_0000_ffff_ffff and 0xffff_ffff_ffff_ffff will end up in
the same hash table bucket.
This change ensures the inode's hash value depends both on the
objectid (inode number) and its subvolume's (btree root) objectid.
For 32 bits machines, this change gives better entropy by making
the hash value depend on both the upper and lower 32 bits of the
64 bits hash previously computed.
Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Remove unused parameter, 'eb'. Unused since introduction in
5f39d397df
Updated to be rebased against current upstream and correct diff supplied this time!
Signed-off-by: Ross Kirk <ross.kirk@gmail.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
I was noticing the slab redzone stuff going off every once and a while during
transaction aborts. This was caused by two things
1) We would walk the pending snapshots and set their error to -ECANCELED. We
don't need to do this, the snapshot stuff waits for a transaction commit and if
there is a problem we just free our pending snapshot object and exit. Doing
this was causing us to touch the pending snapshot object after the thing had
already been freed.
2) We were freeing the transaction manually with wanton disregard for it's
use_count reference counter. To fix this I cleaned up the transaction freeing
loop to either wait for the transaction commit to finish if it was in the middle
of that (since it will be cleaned and freed up there) or to do the cleanup
oursevles.
I also moved the global "kill all things dirty everywhere" stuff outside of the
transaction cleanup loop since that only needs to be done once. With this patch
I'm no longer seeing slab corruption because of use after frees. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
During transaction cleanup after an abort we are just removing roots from the
ordered roots list which is incorrect. We have a BUG_ON() to make sure that the
root is still part of the ordered roots list when we put our ordered extent
which we were tripping in this case. So do like we do everywhere else and just
move it to the tail of the ordered roots list and allow the normal cleanup to
take care of stuff. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
If we abort not during a transaction commit we won't clean up anything until we
unmount. Unfortunately if we abort in the middle of writing out an ordered
extent we won't clean it up and if somebody is waiting on that ordered extent
they will wait forever. To fix this just make the transaction kthread call the
cleanup transaction stuff if it notices theres an error, and make
btrfs_end_transaction wake up the transaction kthread if there is an error.
Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
While looking at somebodys corruption I became completely convinced that
btrfs_split_item was broken, so I wrote this test to verify that it was working
as it was supposed to. Thankfully it appears to be working as intended, so just
add this test to make sure nobody breaks it in the future. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
The fact that btrfs_root_refs() returned 0 for the tree_root caused
bugs in the past, therefore it is set to 1 with this patch and
(hopefully) all affected code is adapted to this change.
I verified this change by temporarily adding WARN_ON() checks
everywhere where btrfs_root_refs() is used, checking whether the
logic of the code is changed by btrfs_root_refs() returning 1
instead of 0 for root->root_key.objectid == BTRFS_ROOT_TREE_OBJECTID.
With these added checks, I ran the xfstests './check -g auto'.
The two roots chunk_root and log_root_tree that are only referenced
by the superblock and the log_roots below the log_root_tree still
have btrfs_root_refs() == 0, only the tree_root is changed.
Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
When doing space balance and subvolume destroy at the same time, we met
the following oops:
kernel BUG at fs/btrfs/relocation.c:2247!
RIP: 0010: [<ffffffffa04cec16>] prepare_to_merge+0x154/0x1f0 [btrfs]
Call Trace:
[<ffffffffa04b5ab7>] relocate_block_group+0x466/0x4e6 [btrfs]
[<ffffffffa04b5c7a>] btrfs_relocate_block_group+0x143/0x275 [btrfs]
[<ffffffffa0495c56>] btrfs_relocate_chunk.isra.27+0x5c/0x5a2 [btrfs]
[<ffffffffa0459871>] ? btrfs_item_key_to_cpu+0x15/0x31 [btrfs]
[<ffffffffa048b46a>] ? btrfs_get_token_64+0x7e/0xcd [btrfs]
[<ffffffffa04a3467>] ? btrfs_tree_read_unlock_blocking+0xb2/0xb7 [btrfs]
[<ffffffffa049907d>] btrfs_balance+0x9c7/0xb6f [btrfs]
[<ffffffffa049ef84>] btrfs_ioctl_balance+0x234/0x2ac [btrfs]
[<ffffffffa04a1e8e>] btrfs_ioctl+0xd87/0x1ef9 [btrfs]
[<ffffffff81122f53>] ? path_openat+0x234/0x4db
[<ffffffff813c3b78>] ? __do_page_fault+0x31d/0x391
[<ffffffff810f8ab6>] ? vma_link+0x74/0x94
[<ffffffff811250f5>] vfs_ioctl+0x1d/0x39
[<ffffffff811258c8>] do_vfs_ioctl+0x32d/0x3e2
[<ffffffff811259d4>] SyS_ioctl+0x57/0x83
[<ffffffff813c3bfa>] ? do_page_fault+0xe/0x10
[<ffffffff813c73c2>] system_call_fastpath+0x16/0x1b
It is because we returned the error number if the reference of the root was 0
when doing space relocation. It was not right here, because though the root
was dead(refs == 0), but the space it held still need be relocated, or we
could not remove the block group. So in this case, we should return the root
no matter it is dead or not.
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
The BUG() was replaced by btrfs_error() and return -EIO with the
patch "get rid of one BUG() in write_all_supers()", but the missing
mutex_unlock() was overlooked.
The 0-DAY kernel build service from Intel reported the missing
unlock which was found by the coccinelle tool:
fs/btrfs/disk-io.c:3422:2-8: preceding lock on line 3374
Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
We only need an async starter if we can't make a GFP_NOFS allocation in our
current path. This is the case for the endio stuff since it happens in IRQ
context, but things like the caching thread workers and the delalloc flushers we
can easily make this allocation and start threads right away. Also change the
worker count for the caching thread pool. Traditionally we limited this to 2
since we took read locks while caching, but nowadays we do this lockless so
there's no reason to limit the number of caching threads. Thanks,
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Mitch Harder noticed that the patch 3c64a1a mentioned in the subject
line was causing a kernel BUG() on snapshot deletion.
The patch was wrong. It did not handle cached roots correctly. The
check for root_refs == 0 was removed everywhere where
btrfs_read_fs_root_no_name() had been used to retrieve the root,
because this check was already dealt with in
btrfs_read_fs_root_no_name(). But in the case when the root was
found in the cache, there was no such check.
This patch adds the missing check in the case where the root is
found in the cache.
Reported-by: Mitch Harder <mitch.harder@sabayonlinux.org>
Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Reviewed-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
The second round uses btrfs_error() and return -EIO, the first round
can handle write errors the same way.
Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
This change fixes an issue when removing a device and writing
all super blocks run simultaneously. Here's the steps necessary
for the issue to happen:
1) disk-io.c:write_all_supers() gets a number of N devices from the
super_copy, so it will not panic if it fails to write super blocks
for N - 1 devices;
2) Then it tries to acquire the device_list_mutex, but blocks because
volumes.c:btrfs_rm_device() got it first;
3) btrfs_rm_device() removes the device from the list, then unlocks the
mutex and after the unlock it updates the number of devices in
super_copy to N - 1.
4) write_all_supers() finally acquires the mutex, iterates over all the
devices in the list and gets N - 1 errors, that is, it failed to write
super blocks to all the devices;
5) Because write_all_supers() thinks there are a total of N devices, it
considers N - 1 errors to be ok, and therefore won't panic.
So this change just makes sure that write_all_supers() reads the number
of devices from super_copy after it acquires the device_list_mutex.
Conversely, it changes btrfs_rm_device() to update the number of devices
in super_copy before it releases the device list mutex.
The code path to add a new device (volumes.c:btrfs_init_new_device),
already has the right behaviour: it updates the number of devices in
super_copy while holding the device_list_mutex.
The only code path that doesn't lock the device list mutex
before updating the number of devices in the super copy is
disk-io.c:next_root_backup(), called by open_ctree() during
mount time where concurrency issues can't happen.
Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Qu Wenruo