Commit Graph

1018 Commits

Author SHA1 Message Date
Christoph Hellwig
5af7926ff3 enforce ->sync_fs is only called for rw superblock
Make sure a superblock really is writeable by checking MS_RDONLY
under s_umount.  sync_filesystems needed some re-arragement for
that, but all but one sync_filesystem caller had the correct locking
already so that we could add that check there.  cachefiles grew
s_umount locking.

I've also added a WARN_ON to sync_filesystem to assert this for
future callers.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-11 21:36:06 -04:00
Christoph Hellwig
59d697b702 btrfs: remove ->write_super and stop maintaining ->s_dirt
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-11 21:36:05 -04:00
Chris Mason
b263c2c8bf Btrfs: fix extent_buffer leak during tree log replay
During tree log replay, we read in the tree log roots,
process them and then free them.  A recent change
takes an extra reference on the root node of the tree
when the root is read in, and stores that reference
in root->commit_root.

This reference was not being freed, leaving us with
one buffer pinned in ram for each subvol with
a tree log root after a crash.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-06-11 11:24:47 -04:00
Chris Mason
0b4dcea579 Btrfs: fix oops when btrfs_inherit_iflags called with a NULL dir
This happens during subvol creation.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-06-11 11:13:35 -04:00
Chris Mason
067c28adc5 Btrfs: fix -o nodatasum printk spelling
It was printing nodatacsum, which was not the correct option name.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-06-11 09:30:13 -04:00
Yan Zheng
85d4198e40 Btrfs: check duplicate backrefs for both data and metadata
lookup_inline_extent_backref only checks for duplicate backref for data
extents. It assumes backrefs for tree block never conflict.

This patch makes lookup_inline_extent_backref check for duplicate backrefs
for both data and tree block, so that we can detect potential bug earlier.
This is a safety check, strictly speaking it is not required.

Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-06-11 08:51:34 -04:00
Shin Hong
fd0fb038d5 Btrfs: init worker struct fields before kthread-run
This patch fixes a bug which may result race condition
between btrfs_start_workers() and worker_loop().

btrfs_start_workers() executed in a parent thread writes
on workers->worker and worker_loop() in a child thread
reads workers->worker. However, there is no synchronization
enforcing the order of two operations.

This patch makes btrfs_start_workers() fill workers->worker
before it starts a child thread with worker_loop()

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-06-10 20:11:29 -04:00
Hisashi Hifumi
4eedeb75e7 Btrfs: pin buffers during write_dev_supers
write_dev_supers is called in sequence.  First is it called with wait == 0,
which starts IO on all of the super blocks for a given device.  Then it is
called with wait == 1 to make sure they all reach the disk.

It doesn't currently pin the buffers between the two calls, and it also
assumes the buffers won't go away between the two calls, leading to
an oops if the VM manages to free the buffers in the middle of the sync.

This fixes that assumption and updates the code to return an error if things
are not up to date when the wait == 1 run is done.

Signed-off-by: Hisashi Hifumi <hifumi.hisashi@oss.ntt.co.jp>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-06-10 16:49:25 -04:00
Chris Mason
e5e9a5206a Btrfs: avoid races between super writeout and device list updates
On multi-device filesystems, btrfs writes supers to all of the devices
before considering a sync complete.  There wasn't any additional
locking between super writeout and the device list management code
because device management was done inside a transaction and
super writeout only happened  with no transation writers running.

With the btrfs fsync log and other async transaction updates, this
has been racey for some time.  This adds a mutex to protect
the device list.  The existing volume mutex could not be reused due to
transaction lock ordering requirements.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-06-10 15:17:02 -04:00
Al Viro
7df336ec12 Fix btrfs when ACLs are configured out
... otherwise generic_permission() will allow *anything* for all
files you don't own and that have some group permissions.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-06-10 11:36:43 -04:00
Hisashi Hifumi
524724ed1f Btrfs: fdatasync should skip metadata writeout
In btrfs, fdatasync and fsync are identical, but
fdatasync should skip committing transaction when
inode->i_state is set just I_DIRTY_SYNC and this indicates
only atime or/and mtime updates.
Following patch improves fdatasync throughput.

--file-block-size=4K --file-total-size=16G --file-test-mode=rndwr
--file-fsync-mode=fdatasync run

Results:
-2.6.30-rc8
Test execution summary:
    total time:                          1980.6540s
    total number of events:              10001
    total time taken by event execution: 1192.9804
    per-request statistics:
         min:                            0.0000s
         avg:                            0.1193s
         max:                            15.3720s
         approx.  95 percentile:         0.7257s

Threads fairness:
    events (avg/stddev):           625.0625/151.32
    execution time (avg/stddev):   74.5613/9.46

-2.6.30-rc8-patched
Test execution summary:
    total time:                          1695.9118s
    total number of events:              10000
    total time taken by event execution: 871.3214
    per-request statistics:
         min:                            0.0000s
         avg:                            0.0871s
         max:                            10.4644s
         approx.  95 percentile:         0.4787s

Threads fairness:
    events (avg/stddev):           625.0000/131.86
    execution time (avg/stddev):   54.4576/8.98

Signed-off-by: Hisashi Hifumi <hifumi.hisashi@oss.ntt.co.jp>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-06-10 11:29:53 -04:00
David Woodhouse
163e783e6a Btrfs: remove crc32c.h and use libcrc32c directly.
There's no need to preserve this abstraction; it used to let us use
hardware crc32c support directly, but libcrc32c is already doing that for us
through the crypto API -- so we're already using the Intel crc32c
acceleration where appropriate.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-06-10 11:29:53 -04:00
Christoph Hellwig
6cbff00f46 Btrfs: implement FS_IOC_GETFLAGS/SETFLAGS/GETVERSION
Add support for the standard attributes set via chattr and read via
lsattr.  Currently we store the attributes in the flags value in
the btrfs inode, but I wonder whether we should split it into two so
that we don't have to keep converting between the two formats.

Remove the btrfs_clear_flag/btrfs_set_flag/btrfs_test_flag macros
as they were confusing the existing code and got in the way of the
new additions.

Also add the FS_IOC_GETVERSION ioctl for getting i_generation as it's
trivial.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-06-10 11:29:52 -04:00
Chris Mason
c289811cc0 Btrfs: autodetect SSD devices
During mount, btrfs will check the queue nonrot flag
for all the devices found in the FS.  If they are all
non-rotating, SSD mode is enabled by default.

If the FS was mounted with -o nossd, the non-rotating
flag is ignored.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-06-10 11:29:52 -04:00
Chris Mason
451d7585a8 Btrfs: add mount -o ssd_spread to spread allocations out
Some SSDs perform best when reusing block numbers often, while
others perform much better when clustering strictly allocates
big chunks of unused space.

The default mount -o ssd will find rough groupings of blocks
where there are a bunch of free blocks that might have some
allocated blocks mixed in.

mount -o ssd_spread will make sure there are no allocated blocks
mixed in.  It should perform better on lower end SSDs.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-06-10 11:29:52 -04:00
Chris Mason
c604480171 Btrfs: avoid allocation clusters that are too spread out
In SSD mode for data, and all the time for metadata the allocator
will try to find a cluster of nearby blocks for allocations.  This
commit adds extra checks to make sure that each free block in the
cluster is close to the last one.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-06-10 11:29:51 -04:00
Chris Mason
3b30c22f64 Btrfs: Add mount -o nossd
This allows you to turn off the ssd mode via remount.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-06-10 11:29:50 -04:00
Chris Mason
d644d8a1e3 Btrfs: avoid IO stalls behind congested devices in a multi-device FS
The btrfs IO submission threads try to service a bunch of devices with a small
number of threads.  They do a congestion check to try and avoid waiting
on requests for a busy device.

The checks make sure we've sent a few requests down to a given device just so
that we aren't bouncing between busy devices without actually sending down
any IO.  The counter used to decide if we can switch to the next device
is somewhat overloaded.  It is also being used to decide if we've done
a good batch of requests between the WRITE_SYNC or regular priority lists.
It may get reset to zero often, leaving us hammering on a busy device
instead of moving on to another disk.

This commit adds a new counter for the number of bios sent while
servicing a device.  It doesn't get reset or fiddled with.  On
multi-device filesystems, this fixes IO stalls in streaming
write workloads.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-06-10 11:29:49 -04:00
Chris Mason
d84275c938 Btrfs: don't allow WRITE_SYNC bios to starve out regular writes
Btrfs uses dedicated threads to submit bios when checksumming is on,
which allows us to make sure the threads dedicated to checksumming don't get
stuck waiting for requests.  For each btrfs device, there are
two lists of bios.  One list is for WRITE_SYNC bios and the other
is for regular priority bios.

The IO submission threads used to process all of the WRITE_SYNC bios first and
then switch to the regular bios.  This commit makes sure we don't completely
starve the regular bios by rotating between the two lists.

WRITE_SYNC bios are still favored 2:1 over the regular bios, and this tries
to run in batches to avoid seeking.  Benchmarking shows this eliminates
stalls during streaming buffered writes on both multi-device and
single device filesystems.

If the regular bios starve, the system can end up with a large amount of ram
pinned down in writeback pages.  If we are a little more fair between the two
classes, we're able to keep throughput up and make progress on the bulk of
our dirty ram.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-06-10 11:29:49 -04:00
Chris Mason
585ad2c379 Btrfs: fix metadata dirty throttling limits
Once a metadata block has been written, it must be recowed, so the
btrfs dirty balancing call has a check to make sure a fair amount of metadata
was actually dirty before it started writing it back to disk.

A previous commit had changed the dirty tracking for metadata without
updating the btrfs dirty balancing checks.  This commit switches it
to use the correct counter.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-06-10 11:29:48 -04:00
Chris Mason
2c943de6ad Btrfs: reduce mount -o ssd CPU usage
The block allocator in SSD mode will try to find groups of free blocks
that are close together.  This commit makes it loop less on a given
group size before bumping it.

The end result is that we are less likely to fill small holes in the
available free space, but we don't waste as much CPU building the
large cluster used by ssd mode.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-06-10 11:29:48 -04:00
Chris Mason
cfbb930846 Btrfs: balance btree more often
With the new back reference code, the cost of a balance has gone down
in terms of the number of back reference updates done.  This commit
makes us more aggressively balance leaves and nodes as they become
less full.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-06-10 11:29:47 -04:00
Chris Mason
b361242102 Btrfs: stop avoiding balancing at the end of the transaction.
When the delayed reference code was added, some checks were added
to avoid extra balancing while the delayed references were being flushed.
This made for less efficient btrees, but it reduced the chances of
loops where no forward progress was made because the balances made
more delayed ref updates.

With the new dead root removal code and the mixed back references,
the extent allocation tree is no longer using precise back refs, and
the delayed reference updates don't carry the risk of looping forever
anymore.  So, the balance avoidance is no longer required.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-06-10 11:29:47 -04:00
Yan Zheng
5d4f98a28c Btrfs: Mixed back reference (FORWARD ROLLING FORMAT CHANGE)
This commit introduces a new kind of back reference for btrfs metadata.
Once a filesystem has been mounted with this commit, IT WILL NO LONGER
BE MOUNTABLE BY OLDER KERNELS.

When a tree block in subvolume tree is cow'd, the reference counts of all
extents it points to are increased by one.  At transaction commit time,
the old root of the subvolume is recorded in a "dead root" data structure,
and the btree it points to is later walked, dropping reference counts
and freeing any blocks where the reference count goes to 0.

The increments done during cow and decrements done after commit cancel out,
and the walk is a very expensive way to go about freeing the blocks that
are no longer referenced by the new btree root.  This commit reduces the
transaction overhead by avoiding the need for dead root records.

When a non-shared tree block is cow'd, we free the old block at once, and the
new block inherits old block's references. When a tree block with reference
count > 1 is cow'd, we increase the reference counts of all extents
the new block points to by one, and decrease the old block's reference count by
one.

This dead tree avoidance code removes the need to modify the reference
counts of lower level extents when a non-shared tree block is cow'd.
But we still need to update back ref for all pointers in the block.
This is because the location of the block is recorded in the back ref
item.

We can solve this by introducing a new type of back ref. The new
back ref provides information about pointer's key, level and in which
tree the pointer lives. This information allow us to find the pointer
by searching the tree. The shortcoming of the new back ref is that it
only works for pointers in tree blocks referenced by their owner trees.

This is mostly a problem for snapshots, where resolving one of these
fuzzy back references would be O(number_of_snapshots) and quite slow.
The solution used here is to use the fuzzy back references in the common
case where a given tree block is only referenced by one root,
and use the full back references when multiple roots have a reference
on a given block.

This commit adds per subvolume red-black tree to keep trace of cached
inodes. The red-black tree helps the balancing code to find cached
inodes whose inode numbers within a given range.

This commit improves the balancing code by introducing several data
structures to keep the state of balancing. The most important one
is the back ref cache. It caches how the upper level tree blocks are
referenced. This greatly reduce the overhead of checking back ref.

The improved balancing code scales significantly better with a large
number of snapshots.

This is a very large commit and was written in a number of
pieces.  But, they depend heavily on the disk format change and were
squashed together to make sure git bisect didn't end up in a
bad state wrt space balancing or the format change.

Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-06-10 11:29:46 -04:00
Yan Zheng
5c939df56c btrfs: Fix set/clear_extent_bit for 'end == (u64)-1'
There are some 'start = state->end + 1;' like code in set_extent_bit
and clear_extent_bit. They overflow when end == (u64)-1.

Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-06-10 11:29:46 -04:00
Linus Torvalds
064e38aade Merge git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable
* git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable:
  Btrfs: Fix oops and use after free during space balancing
  Btrfs: set device->total_disk_bytes when adding new device
2009-06-05 11:54:28 -07:00
Chris Mason
44fb551163 Btrfs: Fix oops and use after free during space balancing
The btrfs allocator uses list_for_each to walk the available block
groups when searching for free blocks.  It starts off with a hint
to help find the best block group for a given allocation.

The hint is resolved into a block group, but we don't properly check
to make sure the block group we find isn't in the middle of being
freed due to filesystem shrinking or balancing.  If it is being
freed, the list pointers in it are bogus and can't be trusted.  But,
the code happily goes along and uses them in the list_for_each loop,
leading to all kinds of fun.

The fix used here is to check to make sure the block group we find really
is on the list before we use it.  list_del_init is used when removing
it from the list, so we can do a proper check.

The allocation clustering code has a similar bug where it will trust
the block group in the current free space cluster.  If our allocation
flags have changed (going from single spindle dup to raid1 for example)
because the drives in the FS have changed, we're not allowed to use
the old block group any more.

The fix used here is to check the current cluster against the
current allocation flags.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-06-04 15:41:27 -04:00
Yan Zheng
2cc3c559fb Btrfs: set device->total_disk_bytes when adding new device
It was not being properly initialized, and so the size saved to
disk was not correct.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-06-04 09:23:57 -04:00
Linus Torvalds
5732c46849 Merge git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable
* git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable:
  Btrfs: Spelling fix in btrfs_lookup_first_block_group comments
  Btrfs: make show_options result match actual option names
  Btrfs: remove outdated comment in btrfs_ioctl_resize()
  Btrfs: remove some WARN_ONs in the IO failure path
  Btrfs: Don't loop forever on metadata IO failures
  Btrfs: init inode ordered_data_close flag properly
2009-05-14 19:18:44 -07:00
Sankar P
9f55684c2d Btrfs: Spelling fix in btrfs_lookup_first_block_group comments
Signed-off-by: Sankar P <sankar.curiosity@gmail.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-05-14 14:00:34 -04:00
Sage Weil
6b65c5c61b Btrfs: make show_options result match actual option names
The notreelog and flushoncommit mount options were being printed slightly
differently.

Signed-off-by: Sage Weil <sage@newdream.net>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-05-14 14:00:34 -04:00
Li Hong
5d847a8ed9 Btrfs: remove outdated comment in btrfs_ioctl_resize()
In Li Zefan's commit dae7b665cf,
a combination call of kmalloc() and copy_from_user() is replaced by
memdup_user(). So btrfs_ioctl_resize() doesn't use GFP_NOFS any more.

Signed-off-by: Li Hong <lihong.hi@gmail.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-05-14 14:00:33 -04:00
Chris Mason
cc7b0c9b70 Btrfs: remove some WARN_ONs in the IO failure path
These debugging WARN_ONs make too much console noise during regular
IO failures.  An IO failure will still generate a number of messages
as we verify checksums etc, but these two are not needed.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-05-14 14:00:33 -04:00
Chris Mason
76a05b35a3 Btrfs: Don't loop forever on metadata IO failures
When a btrfs metadata read fails, the first thing we try to do is find
a good copy on another mirror of the block.  If this fails, read_tree_block()
ends up returning a buffer that isn't up to date.

The btrfs btree reading code was reworked to drop locks and repeat
the search when IO was done, but the changes didn't add a check for failed
reads.  The end result was looping forever on buffers that were never
going to become up to date.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-05-14 14:00:32 -04:00
Chris Mason
2757495c90 Btrfs: init inode ordered_data_close flag properly
This flag is used to decide when we need to send a given file through
the ordered code to make sure it is fully written before a transaction
commits.  It was not being properly set to zero when the inode was
being setup.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-05-14 14:00:31 -04:00
Al Viro
6f5bbff9a1 Convert obvious places to deactivate_locked_super()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-05-09 10:49:40 -04:00
Linus Torvalds
4ebf662337 Merge git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable
* git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable:
  Btrfs: look for acls during btrfs_read_locked_inode
  Btrfs: fix acl caching
  Btrfs: Fix a bunch of printk() warnings.
  Btrfs: Fix a trivial warning using max() of u64 vs ULL.
  Btrfs: remove unused btrfs_bit_radix slab
  Btrfs: ratelimit IO error printks
  Btrfs: remove #if 0 code
  Btrfs: When shrinking, only update disk size on success
  Btrfs: fix deadlocks and stalls on dead root removal
  Btrfs: fix fallocate deadlock on inode extent lock
  Btrfs: kill btrfs_cache_create
  Btrfs: don't export symbols
  Btrfs: simplify makefile
  Btrfs: try to keep a healthy ratio of metadata vs data block groups
2009-04-27 11:16:33 -07:00
Chris Mason
46a53cca82 Btrfs: look for acls during btrfs_read_locked_inode
This changes btrfs_read_locked_inode() to peek ahead in the btree for acl items.
If it is certain a given inode has no acls, it will set the in memory acl
fields to null to avoid acl lookups completely.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-04-27 13:18:35 -04:00
Chris Mason
7b1a14bbb0 Btrfs: fix acl caching
Linus noticed the btrfs code to cache acls wasn't properly caching
a NULL acl when the inode didn't have any acls.  This meant the common
case of no acls resulted in expensive btree searches every time the
kernel checked permissions (which is quite often).

This is a modified version of Linus' original patch:

Properly set initial acl fields to BTRFS_ACL_NOT_CACHED in the inode.
This forces an acl lookup when permission checks are done.

Fix btrfs_get_acl to avoid lookups and locking when the inode acls fields
are set to null.

Fix btrfs_get_acl to use the right return value from __btrfs_getxattr
when deciding to cache a NULL acl.  It was storing a NULL acl when
__btrfs_getxattr return -ENOENT, but __btrfs_getxattr was actually returning
-ENODATA for this case.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-04-27 13:18:26 -04:00
Joel Becker
21380931eb Btrfs: Fix a bunch of printk() warnings.
Just happened to notice a bunch of %llu vs u64 warnings.  Here's a patch
to cast them all.

Signed-off-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-04-27 08:37:49 -04:00
Joel Becker
e63b6a6c0f Btrfs: Fix a trivial warning using max() of u64 vs ULL.
A small warning popped up on ia64 because inode-map.c was comparing a
u64 object id with the ULL FIRST_FREE_OBJECTID.  My first thought was
that all the OBJECTID constants should contain the u64 cast because
btrfs code deals entirely in u64s.  But then I saw how large that was,
and figured I'd just fix the max() call.

Signed-off-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-04-27 08:37:49 -04:00
Chris Mason
45c06543af Btrfs: remove unused btrfs_bit_radix slab
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-04-27 08:37:48 -04:00
Chris Mason
193f284d49 Btrfs: ratelimit IO error printks
Btrfs has printks for various IO errors, including bad checksums and
mismatches between what we expect the block headers to contain and what
we actually find on the disk.

Longer term we need a real reporting mechanism for this, but for now
printk is going to have to do.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-04-27 07:41:47 -04:00
Chris Mason
b7967db75a Btrfs: remove #if 0 code
Btrfs had some old code sitting around under #if 0, this drops it.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-04-27 07:40:52 -04:00
Chris Ball
d6397baee4 Btrfs: When shrinking, only update disk size on success
Previously, we updated a device's size prior to attempting a shrink
operation.  This patch moves the device resizing logic to only happen if
the shrink completes successfully.  In the process, it introduces a new
field to btrfs_device -- disk_total_bytes -- to track the on-disk size.

Signed-off-by: Chris Ball <cjb@laptop.org>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-04-27 07:40:51 -04:00
Chris Mason
59bc5c758e Btrfs: fix deadlocks and stalls on dead root removal
After a transaction commit, the old root of the subvol btrees are sent through
snapshot removal.  This is what actually frees up any blocks replaced by
COW, and anything the old blocks pointed to.

Snapshot deletion will pause when a transaction commit has started, which
helps to avoid a huge amount of delayed reference count updates piling up
as the transaction is trying to close.

But, this pause happens after the snapshot deletion process has asked other
procs on the system to throttle back a bit so that it can make progress.

We don't want to throttle everyone while we're waiting for the transaction
commit, it leads to deadlocks in the user transaction ioctls used by Ceph
and makes things slower in general.

This patch changes things to avoid the throttling while we sleep.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-04-24 15:46:05 -04:00
Chris Mason
e980b50cda Btrfs: fix fallocate deadlock on inode extent lock
The btrfs fallocate call takes an extent lock on the entire range
being fallocated, and then runs through insert_reserved_extent on each
extent as they are allocated.

The problem with this is that btrfs_drop_extents may decide to try
and take the same extent lock fallocate was already holding.  The solution
used here is to push down knowledge of the range that is already locked
going into btrfs_drop_extents.

It turns out that at least one other caller had the same bug.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-04-24 15:46:05 -04:00
Christoph Hellwig
9601e3f633 Btrfs: kill btrfs_cache_create
Just use kmem_cache_create directly.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-04-24 15:46:04 -04:00
Christoph Hellwig
0d4bf11e53 Btrfs: don't export symbols
Currently the extent_map code is only for btrfs so don't export it's
symbols.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-04-24 15:46:04 -04:00
Christoph Hellwig
2ea2544ef5 Btrfs: simplify makefile
Get rid of the hacks for building out of tree, and always use += for
assigning to the object lists.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2009-04-24 15:46:03 -04:00