Commit Graph

1521 Commits

Author SHA1 Message Date
Tsutomu Itoh
91ca338d77 btrfs: check NULL or not
Should check if functions returns NULL or not.

Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-01-16 11:30:20 -05:00
Jesper Juhl
ff175d57f0 btrfs: Don't pass NULL ptr to func that may deref it.
Hi,

In fs/btrfs/inode.c::fixup_tree_root_location() we have this code:

...
 		if (!path) {
 			err = -ENOMEM;
 			goto out;
 		}
...
 	out:
 		btrfs_free_path(path);
 		return err;

btrfs_free_path() passes its argument on to other functions and some of
them end up dereferencing the pointer.
In the code above that pointer is clearly NULL, so btrfs_free_path() will
eventually cause a NULL dereference.

There are many ways to cut this cake (fix the bug). The one I chose was to
make btrfs_free_path() deal gracefully with NULL pointers. If you
disagree, feel free to come up with an alternative patch.

Signed-off-by: Jesper Juhl <jj@chaosbits.net>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-01-16 11:30:20 -05:00
Dave Young
20b450773d btrfs: mount failure return value fix
I happened to pass swap partition as root partition in cmdline,
then kernel panic and tell me about "Cannot open root device".
It is not correct, in fact it is a fs type mismatch instead of 'no device'.

Eventually I found btrfs mounting failed with -EIO, it should be -EINVAL.
The logic in init/do_mounts.c:
        for (p = fs_names; *p; p += strlen(p)+1) {
                int err = do_mount_root(name, p, flags, root_mount_data);
                switch (err) {
                        case 0:
                                goto out;
                        case -EACCES:
                                flags |= MS_RDONLY;
                                goto retry;
                        case -EINVAL:
                                continue;
                }
		print "Cannot open root device"
		panic
	}
SO fs type after btrfs will have no chance to mount

Here fix the return value as -EINVAL

Signed-off-by: Dave Young <hidave.darkstar@gmail.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-01-16 11:30:19 -05:00
Jesper Juhl
42838bb265 btrfs: Mem leak in btrfs_get_acl()
It seems to me that we leak the memory allocated to 'value' in
btrfs_get_acl() if the call to posix_acl_from_xattr() fails.
Here's a patch that attempts to correct that problem.

Signed-off-by: Jesper Juhl <jj@chaosbits.net>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-01-16 11:30:19 -05:00
Miao Xie
6d07bcec96 btrfs: fix wrong free space information of btrfs
When we store data by raid profile in btrfs with two or more different size
disks, df command shows there is some free space in the filesystem, but the
user can not write any data in fact, df command shows the wrong free space
information of btrfs.

 # mkfs.btrfs -d raid1 /dev/sda9 /dev/sda10
 # btrfs-show
 Label: none  uuid: a95cd49e-6e33-45b8-8741-a36153ce4b64
 	Total devices 2 FS bytes used 28.00KB
 	devid    1 size 5.01GB used 2.03GB path /dev/sda9
 	devid    2 size 10.00GB used 2.01GB path /dev/sda10
 # btrfs device scan /dev/sda9 /dev/sda10
 # mount /dev/sda9 /mnt
 # dd if=/dev/zero of=tmpfile0 bs=4K count=9999999999
   (fill the filesystem)
 # sync
 # df -TH
 Filesystem	Type	Size	Used	Avail	Use%	Mounted on
 /dev/sda9	btrfs	17G	8.6G	5.4G	62%	/mnt
 # btrfs-show
 Label: none  uuid: a95cd49e-6e33-45b8-8741-a36153ce4b64
 	Total devices 2 FS bytes used 3.99GB
 	devid    1 size 5.01GB used 5.01GB path /dev/sda9
 	devid    2 size 10.00GB used 4.99GB path /dev/sda10

It is because btrfs cannot allocate chunks when one of the pairing disks has
no space, the free space on the other disks can not be used for ever, and should
be subtracted from the total space, but btrfs doesn't subtract this space from
the total. It is strange to the user.

This patch fixes it by calcing the free space that can be used to allocate
chunks.

Implementation:
1. get all the devices free space, and align them by stripe length.
2. sort the devices by the free space.
3. check the free space of the devices,
   3.1. if it is not zero, and then check the number of the devices that has
        more free space than this device,
        if the number of the devices is beyond the min stripe number, the free
        space can be used, and add into total free space.
        if the number of the devices is below the min stripe number, we can not
        use the free space, the check ends.
   3.2. if the free space is zero, check the next devices, goto 3.1

This implementation is just likely fake chunk allocation.

After appling this patch, df can show correct space information:
 # df -TH
 Filesystem	Type	Size	Used	Avail	Use%	Mounted on
 /dev/sda9	btrfs	17G	8.6G	0	100%	/mnt

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-01-16 11:30:19 -05:00
Miao Xie
b2117a39fa btrfs: make the chunk allocator utilize the devices better
With this patch, we change the handling method when we can not get enough free
extents with default size.

Implementation:
1. Look up the suitable free extent on each device and keep the search result.
   If not find a suitable free extent, keep the max free extent
2. If we get enough suitable free extents with default size, chunk allocation
   succeeds.
3. If we can not get enough free extents, but the number of the extent with
   default size is >= min_stripes, we just change the mapping information
   (reduce the number of stripes in the extent map), and chunk allocation
   succeeds.
4. If the number of the extent with default size is < min_stripes, sort the
   devices by its max free extent's size descending
5. Use the size of the max free extent on the (num_stripes - 1)th device as the
   stripe size to allocate the device space

By this way, the chunk allocator can allocate chunks as large as possible when
the devices' space is not enough and make full use of the devices.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-01-16 11:30:19 -05:00
Miao Xie
7bfc837df9 btrfs: restructure find_free_dev_extent()
- make it return the start position and length of the max free space when it can
  not find a suitable free space.
- make it more readability

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-01-16 11:30:19 -05:00
Miao Xie
1974a3b42d btrfs: fix wrong calculation of stripe size
There are two tiny problem:
- One is When we check the chunk size is greater than the max chunk size or not,
  we should take mirrors into account, but the original code didn't.
- The other is btrfs shouldn't use the size of the residual free space as the
  length of of a dup chunk when doing chunk allocation. It is because the device
  space that a dup chunk needs is twice as large as the chunk size, if we use
  the size of the residual free space as the length of a dup chunk, we can not
  get enough free space. Fix it.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Reviewed-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-01-16 11:30:19 -05:00
Miao Xie
d52a5b5f1f btrfs: try to reclaim some space when chunk allocation fails
We cannot write data into files when when there is tiny space in the filesystem.

Reproduce steps:
 # mkfs.btrfs /dev/sda1
 # mount /dev/sda1 /mnt
 # dd if=/dev/zero of=/mnt/tmpfile0 bs=4K count=1
 # dd if=/dev/zero of=/mnt/tmpfile1 bs=4K count=99999999999999
   (fill the filesystem)
 # umount /mnt
 # mount /dev/sda1 /mnt
 # rm -f /mnt/tmpfile0
 # dd if=/dev/zero of=/mnt/tmpfile0 bs=4K count=1
   (failed with nospec)

But if we do the last step again, we can write data successfully. The reason of
the problem is that btrfs didn't try to commit the current transaction and
reclaim some space when chunk allocation failed.

This patch fixes it by committing the current transaction to reclaim some
space when chunk allocation fails.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Reviewed-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-01-16 11:30:19 -05:00
Miao Xie
299a08b1c3 btrfs: fix wrong data space statistics
Josef has implemented mixed data/metadata chunks, we must add those chunks'
space just like data chunks.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Reviewed-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-01-16 11:30:19 -05:00
Stefan Schmidt
f580eb0931 fs/btrfs: Fix build of ctree
CC [M]  fs/btrfs/ctree.o
In file included from fs/btrfs/ctree.c:21:0:
fs/btrfs/ctree.h:1003:17: error: field <91>super_kobj<92> has incomplete type
fs/btrfs/ctree.h:1074:17: error: field <91>root_kobj<92> has incomplete type
make[2]: *** [fs/btrfs/ctree.o] Error 1
make[1]: *** [fs/btrfs] Error 2
make: *** [fs] Error 2

We need to include kobject.h here.

Reported-by: Jeff Garzik <jeff@garzik.org>
Fix-suggested-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Stefan Schmidt <stefan@datenfreihafen.org>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-01-16 11:30:19 -05:00
Chris Mason
f892436eb2 Merge branch 'lzo-support' of git://repo.or.cz/linux-btrfs-devel into btrfs-38 2011-01-16 11:25:54 -05:00
Chris Mason
26c79f6ba0 Merge branch 'readonly-snapshots' of git://repo.or.cz/linux-btrfs-devel into btrfs-38 2011-01-16 11:24:45 -05:00
Linus Torvalds
275220f0fc Merge branch 'for-2.6.38/core' of git://git.kernel.dk/linux-2.6-block
* 'for-2.6.38/core' of git://git.kernel.dk/linux-2.6-block: (43 commits)
  block: ensure that completion error gets properly traced
  blktrace: add missing probe argument to block_bio_complete
  block cfq: don't use atomic_t for cfq_group
  block cfq: don't use atomic_t for cfq_queue
  block: trace event block fix unassigned field
  block: add internal hd part table references
  block: fix accounting bug on cross partition merges
  kref: add kref_test_and_get
  bio-integrity: mark kintegrityd_wq highpri and CPU intensive
  block: make kblockd_workqueue smarter
  Revert "sd: implement sd_check_events()"
  block: Clean up exit_io_context() source code.
  Fix compile warnings due to missing removal of a 'ret' variable
  fs/block: type signature of major_to_index(int) to major_to_index(unsigned)
  block: convert !IS_ERR(p) && p to !IS_ERR_NOR_NULL(p)
  cfq-iosched: don't check cfqg in choose_service_tree()
  fs/splice: Pull buf->ops->confirm() from splice_from_pipe actors
  cdrom: export cdrom_check_events()
  sd: implement sd_check_events()
  sr: implement sr_check_events()
  ...
2011-01-13 10:45:01 -08:00
Josef Bacik
23a8519b55 Btrfs: fail if we try to use hole punch
Btrfs doesn't have the ability to punch holes yet, so make sure we return
EOPNOTSUPP if we try to use hole punching through fallocate.  This support can
be added later.  Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-01-12 20:16:44 -05:00
Al Viro
af53d29ac1 switch btrfs, close races
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-01-12 20:02:47 -05:00
Nick Piggin
258a5aa8df btrfs: provide simple rcu-walk ACL implementation
This simple implementation just checks for no ACLs on the inode, and
if so, then the rcu-walk may proceed, otherwise fail it.

Signed-off-by: Nick Piggin <npiggin@kernel.dk>
2011-01-07 17:50:30 +11:00
Nick Piggin
b74c79e993 fs: provide rcu-walk aware permission i_ops
Signed-off-by: Nick Piggin <npiggin@kernel.dk>
2011-01-07 17:50:29 +11:00
Nick Piggin
fb045adb99 fs: dcache reduce branches in lookup path
Reduce some branches and memory accesses in dcache lookup by adding dentry
flags to indicate common d_ops are set, rather than having to check them.
This saves a pointer memory access (dentry->d_op) in common path lookup
situations, and saves another pointer load and branch in cases where we
have d_op but not the particular operation.

Patched with:

git grep -E '[.>]([[:space:]])*d_op([[:space:]])*=' | xargs sed -e 's/\([^\t ]*\)->d_op = \(.*\);/d_set_d_op(\1, \2);/' -e 's/\([^\t ]*\)\.d_op = \(.*\);/d_set_d_op(\&\1, \2);/' -i

Signed-off-by: Nick Piggin <npiggin@kernel.dk>
2011-01-07 17:50:28 +11:00
Nick Piggin
fa0d7e3de6 fs: icache RCU free inodes
RCU free the struct inode. This will allow:

- Subsequent store-free path walking patch. The inode must be consulted for
  permissions when walking, so an RCU inode reference is a must.
- sb_inode_list_lock to be moved inside i_lock because sb list walkers who want
  to take i_lock no longer need to take sb_inode_list_lock to walk the list in
  the first place. This will simplify and optimize locking.
- Could remove some nested trylock loops in dcache code
- Could potentially simplify things a bit in VM land. Do not need to take the
  page lock to follow page->mapping.

The downsides of this is the performance cost of using RCU. In a simple
creat/unlink microbenchmark, performance drops by about 10% due to inability to
reuse cache-hot slab objects. As iterations increase and RCU freeing starts
kicking over, this increases to about 20%.

In cases where inode lifetimes are longer (ie. many inodes may be allocated
during the average life span of a single inode), a lot of this cache reuse is
not applicable, so the regression caused by this patch is smaller.

The cache-hot regression could largely be avoided by using SLAB_DESTROY_BY_RCU,
however this adds some complexity to list walking and store-free path walking,
so I prefer to implement this at a later date, if it is shown to be a win in
real situations. I haven't found a regression in any non-micro benchmark so I
doubt it will be a problem.

Signed-off-by: Nick Piggin <npiggin@kernel.dk>
2011-01-07 17:50:26 +11:00
Nick Piggin
fe15ce446b fs: change d_delete semantics
Change d_delete from a dentry deletion notification to a dentry caching
advise, more like ->drop_inode. Require it to be constant and idempotent,
and not take d_lock. This is how all existing filesystems use the callback
anyway.

This makes fine grained dentry locking of dput and dentry lru scanning
much simpler.

Signed-off-by: Nick Piggin <npiggin@kernel.dk>
2011-01-07 17:50:18 +11:00
Chris Mason
65e5341b9a Btrfs: fix off by one while setting block groups readonly
When we read in block groups, we'll set non-redundant groups
readonly if we find a raid1, DUP or raid10 group.  But the
ro code has an off by one bug in the math around testing to
make sure out accounting doesn't go wrong.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2011-01-04 16:41:39 -05:00
Li Zefan
0caa102da8 Btrfs: Add BTRFS_IOC_SUBVOL_GETFLAGS/SETFLAGS ioctls
This allows us to set a snapshot or a subvolume readonly or writable
on the fly.

Usage:

Set BTRFS_SUBVOL_RDONLY of btrfs_ioctl_vol_arg_v2->flags, and then
call ioctl(BTRFS_IOCTL_SUBVOL_SETFLAGS);

Changelog for v3:

- Change to pass __u64 as ioctl parameter.

Changelog for v2:

- Add _GETFLAGS ioctl.
- Check if the passed fd is the root of a subvolume.
- Change the name from _SNAP_SETFLAGS to _SUBVOL_SETFLAGS.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
2010-12-23 08:49:19 +08:00
Li Zefan
b83cc9693f Btrfs: Add readonly snapshots support
Usage:

Set BTRFS_SUBVOL_RDONLY of btrfs_ioctl_vol_arg_v2->flags, and call
ioctl(BTRFS_I0CTL_SNAP_CREATE_V2).

Implementation:

- Set readonly bit of btrfs_root_item->flags.
- Add readonly checks in btrfs_permission (inode_permission),
btrfs_setattr, btrfs_set/remove_xattr and some ioctls.

Changelog for v3:

- Eliminate btrfs_root->readonly, but check btrfs_root->root_item.flags.
- Rename BTRFS_ROOT_SNAP_RDONLY to BTRFS_ROOT_SUBVOL_RDONLY.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
2010-12-23 08:49:17 +08:00
Li Zefan
fa0d2b9bd7 Btrfs: Refactor btrfs_ioctl_snap_create()
Split it into two functions for two different ioctls, since they
share no common code.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
2010-12-23 08:49:15 +08:00
Li Zefan
3a39c18d63 btrfs: Extract duplicate decompress code
Add a common function to copy decompressed data from working buffer
to bio pages.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
2010-12-22 23:15:50 +08:00
Li Zefan
1a419d85a7 btrfs: Allow to specify compress method when defrag
Update defrag ioctl, so one can choose lzo or zlib when turning
on compression in defrag operation.

Changelog:

v1 -> v2
- Add incompability flag.
- Fix to check invalid compress type.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
2010-12-22 23:15:48 +08:00
Li Zefan
a6fa6fae40 btrfs: Add lzo compression support
Lzo is a much faster compression algorithm than gzib, so would allow
more users to enable transparent compression, and some users can
choose from compression ratio and speed for different applications

Usage:

 # mount -t btrfs -o compress[=<zlib,lzo>] dev /mnt
or
 # mount -t btrfs -o compress-force[=<zlib,lzo>] dev /mnt

"-o compress" without argument is still allowed for compatability.

Compatibility:

If we mount a filesystem with lzo compression, it will not be able be
mounted in old kernels. One reason is, otherwise btrfs will directly
dump compressed data, which sits in inline extent, to user.

Performance:

The test copied a linux source tarball (~400M) from an ext4 partition
to the btrfs partition, and then extracted it.

(time in second)
           lzo        zlib        nocompress
copy:      10.6       21.7        14.9
extract:   70.1       94.4        66.6

(data size in MB)
           lzo        zlib        nocompress
copy:      185.87     108.69      394.49
extract:   193.80     132.36      381.21

Changelog:

v1 -> v2:
- Select LZO_COMPRESS and LZO_DECOMPRESS in btrfs Kconfig.
- Add incompability flag.
- Fix error handling in compress code.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
2010-12-22 23:15:47 +08:00
Li Zefan
261507a02c btrfs: Allow to add new compression algorithm
Make the code aware of compression type, instead of always assuming
zlib compression.

Also make the zlib workspace function as common code for all
compression types.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
2010-12-22 23:15:45 +08:00
Li Zefan
4b72029dc3 btrfs: Fix error handling in zlib
Return failure if alloc_page() fails to allocate memory,
and the upper code will just give up compression.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
2010-12-22 23:15:43 +08:00
Li Zefan
8844355df7 btrfs: Fix bugs in zlib workspace
- Fix a race that can result in alloc_workspace > cpus.
- Fix to check num_workspace after wakeup.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
2010-12-22 23:15:41 +08:00
Al Viro
3cb50ddf97 Fix btrfs b0rkage
Buggered-in: 76dda93c6a ("Btrfs: add snapshot/subvolume destroy
ioctl")

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Chris Mason <chris.mason@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-12-20 09:09:57 -08:00
Linus Torvalds
e13cf63f2b 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: prevent RAID level downgrades when space is low
  Btrfs: account for missing devices in RAID allocation profiles
  Btrfs: EIO when we fail to read tree roots
  Btrfs: fix compiler warnings
  Btrfs: Make async snapshot ioctl more generic
  Btrfs: pwrite blocked when writing from the mmaped buffer of the same page
  Btrfs: Fix a crash when mounting a subvolume
  Btrfs: fix sync subvol/snapshot creation
  Btrfs: Fix page leak in compressed writeback path
  Btrfs: do not BUG if we fail to remove the orphan item for dead snapshots
  Btrfs: fixup return code for btrfs_del_orphan_item
  Btrfs: do not do fast caching if we are allocating blocks for tree_root
  Btrfs: deal with space cache errors better
  Btrfs: fix use after free in O_DIRECT
2010-12-14 11:08:13 -08:00
Chris Mason
83a50de97f Btrfs: prevent RAID level downgrades when space is low
The extent allocator has code that allows us to fill
allocations from any available block group, even if it doesn't
match the raid level we've requested.

This was put in because adding a new drive to a filesystem
made with the default mkfs options actually upgrades the metadata from
single spindle dup to full RAID1.

But, the code also allows us to allocate from a raid0 chunk when we
really want a raid1 or raid10 chunk.  This can cause big trouble because
mkfs creates a small (4MB) raid0 chunk for data and metadata which then
goes unused for raid1/raid10 installs.

The allocator will happily wander in and allocate from that chunk when
things get tight, which is not correct.

The fix here is to make sure that we provide duplication when the
caller has asked for it.  It does all the dups to be any raid level,
which preserves the dup->raid1 upgrade abilities.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-12-13 20:07:01 -05:00
Chris Mason
cd02dca564 Btrfs: account for missing devices in RAID allocation profiles
When we mount in RAID degraded mode without adding a new device to
replace the failed one, we can end up using the wrong RAID flags for
allocations.

This results in strange combinations of block groups (raid1 in a raid10
filesystem) and corruptions when we try to allocate blocks from single
spindle chunks on drives that are actually missing.

The first device has two small 4MB chunks in it that mkfs creates and
these are usually unused in a raid1 or raid10 setup.  But, in -o degraded,
the allocator will fall back to these because the mask of desired raid groups
isn't correct.

The fix here is to count the missing devices as we build up the list
of devices in the system.  This count is used when picking the
raid level to make sure we continue using the same levels that were
in place before we lost a drive.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-12-13 20:06:52 -05:00
Chris Mason
68433b73b1 Btrfs: EIO when we fail to read tree roots
If we just get a plain IO error when we read tree roots, the code
wasn't properly sending that error up the chain.  This allowed mounts to
continue when they should failed, and allowed operations
on partially setup root structs.  The end result was usually oopsen
on spinlocks that hadn't been spun up correctly.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-12-13 14:47:58 -05:00
Jan Beulich
3dd1462e82 Btrfs: fix compiler warnings
... regarding an unused function when !MIGRATION, and regarding a
printk() format string vs argument mismatch.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-12-10 16:29:11 -05:00
Li Zefan
fdfb1e4f6c Btrfs: Make async snapshot ioctl more generic
If we had reserved some bytes in struct btrfs_ioctl_vol_args, we
wouldn't have to create a new structure for async snapshot creation.

Here we convert async snapshot ioctl to use a more generic ABI, as
we'll add more ioctls for snapshots/subvolumes in the future, readonly
snapshots for example.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-12-10 16:29:11 -05:00
Xin Zhong
914ee295af Btrfs: pwrite blocked when writing from the mmaped buffer of the same page
This problem is found in meego testing:
http://bugs.meego.com/show_bug.cgi?id=6672
A file in btrfs is mmaped and the mmaped buffer is passed to pwrite to write to the same page
of the same file. In btrfs_file_aio_write(), the pages is locked by prepare_pages(). So when
btrfs_copy_from_user() is called, page fault happens and the same page needs to be locked again
in filemap_fault(). The fix is to move iov_iter_fault_in_readable() before prepage_pages() to make page
fault happen before pages are locked. And also disable page fault in critical region in
btrfs_copy_from_user().

Reviewed-by: Yan, Zheng<zheng.z.yan@intel.com>
Signed-off-by: Zhong, Xin <xin.zhong@intel.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-12-10 16:29:10 -05:00
Li Zefan
f106e82caa Btrfs: Fix a crash when mounting a subvolume
We should drop dentry before deactivating the superblock, otherwise
we can hit this bug:

BUG: Dentry f349a690{i=100,n=/} still in use (1) [unmount of btrfs loop1]
...

Steps to reproduce the bug:

  # mount /dev/loop1 /mnt
  # mkdir save
  # btrfs subvolume snapshot /mnt save/snap1
  # umount /mnt
  # mount -o subvol=save/snap1 /dev/loop1 /mnt
  (crash)

Reported-by: Michael Niederle <mniederle@gmx.at>
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-12-10 16:29:10 -05:00
Sage Weil
75eaa0e22c Btrfs: fix sync subvol/snapshot creation
We were incorrectly taking the async path even for the sync ioctls by
passing in &transid unconditionally.

There's ample room for further cleanup here, but this keeps the fix simple.

Signed-off-by: Sage Weil <sage@newdream.net>
Reviewed-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-12-10 16:29:10 -05:00
Yan, Zheng
24ae63656a Btrfs: Fix page leak in compressed writeback path
"start + num_bytes >= actual_end" can happen when compressed page writeback races
with file truncation. In that case we need unlock and release pages past the end
of file.

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-12-10 16:29:09 -05:00
Josef Bacik
84cd948cb1 Btrfs: do not BUG if we fail to remove the orphan item for dead snapshots
Not being able to delete an orphan item isn't a horrible thing.  The worst that
happens is the next time around we try and do the orphan cleanup and we can't
find the referenced object and just delete the item and move on.

Signed-off-by: Josef Bacik <josef@redhat.com>
2010-12-10 16:29:04 -05:00
Josef Bacik
7e1fea731d Btrfs: fixup return code for btrfs_del_orphan_item
If the orphan item doesn't exist, we return 1, which doesn't make any sense to
the callers.  Instead return -ENOENT if we didn't find the item.  Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>
2010-12-09 13:57:15 -05:00
Josef Bacik
b8399dee47 Btrfs: do not do fast caching if we are allocating blocks for tree_root
Since the fast caching uses normal tree locking, we can possibly deadlock if we
get to the caching via a btrfs_search_slot() on the tree_root.  So just check to
see if the root we are on is the tree root, and just don't do the fast caching.

Reported-by: Sage Weil <sage@newdream.net>
Signed-off-by: Josef Bacik <josef@redhat.com>
2010-12-09 13:57:13 -05:00
Josef Bacik
2b20982e31 Btrfs: deal with space cache errors better
Currently if the space cache inode generation number doesn't match the
generation number in the space cache header we will just fail to load the space
cache, but we won't mark the space cache as an error, so we'll keep getting that
error each time somebody tries to cache that block group until we actually clear
the thing.  Fix this by marking the space cache as having an error so we only
get the message once.  This patch also makes it so that we don't try and setup
space cache for a block group that isn't cached, since we won't be able to write
it out anyway.  None of these problems are actual problems, they are just
annoying and sub-optimal.  Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>
2010-12-09 13:57:12 -05:00
Josef Bacik
955256f2c3 Btrfs: fix use after free in O_DIRECT
This fixes a bug where we use dip after we have freed it.  Instead just use the
file_offset that was passed to the function.  Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>
2010-12-09 13:57:10 -05:00
Linus Torvalds
aa3fc52546 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: (24 commits)
  Btrfs: don't use migrate page without CONFIG_MIGRATION
  Btrfs: deal with DIO bios that span more than one ordered extent
  Btrfs: setup blank root and fs_info for mount time
  Btrfs: fix fiemap
  Btrfs - fix race between btrfs_get_sb() and umount
  Btrfs: update inode ctime when using links
  Btrfs: make sure new inode size is ok in fallocate
  Btrfs: fix typo in fallocate to make it honor actual size
  Btrfs: avoid NULL pointer deref in try_release_extent_buffer
  Btrfs: make btrfs_add_nondir take parent inode as an argument
  Btrfs: hold i_mutex when calling btrfs_log_dentry_safe
  Btrfs: use dget_parent where we can UPDATED
  Btrfs: fix more ESTALE problems with NFS
  Btrfs: handle NFS lookups properly
  btrfs: make 1-bit signed fileds unsigned
  btrfs: Show device attr correctly for symlinks
  btrfs: Set file size correctly in file clone
  btrfs: Check if dest_offset is block-size aligned before cloning file
  Btrfs: handle the space_cache option properly
  btrfs: Fix early enospc because 'unused' calculated with wrong sign.
  ...
2010-11-29 14:11:08 -08:00
Chris Mason
5a92bc88ce Btrfs: don't use migrate page without CONFIG_MIGRATION
Fixes compile error

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-11-29 09:49:11 -05:00
Chris Mason
163cf09c2a Btrfs: deal with DIO bios that span more than one ordered extent
The new DIO bio splitting code has problems when the bio
spans more than one ordered extent.  This will happen as the
generic DIO code merges our get_blocks calls together into
a bigger single bio.

This fixes things by walking forward in the ordered extent
code finding all the overlapping ordered extents and completing them
all at once.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-11-28 19:56:33 -05:00
Josef Bacik
450ba0ea06 Btrfs: setup blank root and fs_info for mount time
There is a problem with how we use sget, it searches through the list of supers
attached to the fs_type looking for a super with the same fs_devices as what
we're trying to mount.  This depends on sb->s_fs_info being filled, but we don't
fill that in until we get to btrfs_fill_super, so we could hit supers on the
fs_type super list that have a null s_fs_info.  In order to fix that we need to
go ahead and setup a blank root with a blank fs_info to hold fs_devices, that
way our test will work out right and then we can set s_fs_info in
btrfs_set_super, and then open_ctree will simply use our pre-allocated root and
fs_info when setting everything up.  Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-11-27 13:37:51 -05:00
Josef Bacik
975f84fee2 Btrfs: fix fiemap
There are two big problems currently with FIEMAP

1) We return extents for holes.  This isn't supposed to happen, we just don't
return extents for holes and then userspace interprets the lack of an extent as
a hole.

2) We sometimes don't set FIEMAP_EXTENT_LAST properly.  This is because we wait
to see a EXTENT_FLAG_VACANCY flag on the em, but this won't happen if say we ask
fiemap to map up to the last extent in a file, and there is nothing but holes up
to the i_size.  To fix this we need to lookup the last extent in this file and
save the logical offset, so if we happen to try and map that extent we can be
sure to set FIEMAP_EXTENT_LAST.

With this patch we now pass xfstest 225, which we never have before.

Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-11-27 13:37:50 -05:00
Ian Kent
619c8c7639 Btrfs - fix race between btrfs_get_sb() and umount
When mounting a btrfs file system btrfs_test_super() may attempt to
use sb->s_fs_info, the btrfs root, of a super block that is going away
and that has had the btrfs root set to NULL in its ->put_super(). But
if the super block is going away it cannot be an existing super block
so we can return false in this case.

Signed-off-by: Ian Kent <raven@themaw.net>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-11-27 13:37:44 -05:00
Josef Bacik
bc1cbf1f86 Btrfs: update inode ctime when using links
Currently we fail xfstest 236 because we're not updating the inode ctime on
link.  This is a simple fix, and makes it so we pass 236 now.

Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-11-27 13:00:07 -05:00
Josef Bacik
0ed42a63f3 Btrfs: make sure new inode size is ok in fallocate
We have been failing xfstest 228 forever, because we don't check to make sure
the new inode size is acceptable as far as RLIMIT is concerned.  Just check to
make sure it's ok to create a inode with this new size and error out if not.
With this patch we now pass 228.

Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-11-27 13:00:07 -05:00
Josef Bacik
55a61d1d06 Btrfs: fix typo in fallocate to make it honor actual size
There is a typo in __btrfs_prealloc_file_range() where we set the i_size to
actual_len/cur_offset, and then just set it to cur_offset again, and do the same
with btrfs_ordered_update_i_size().  This fixes it back to keeping i_size in a
local variable and then updating i_size properly.  Tested this with

xfs_io -F -f -c "falloc 0 1" -c "pwrite 0 1" foo

stat'ing foo gives us a size of 1 instead of 4096 like it was.  Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-11-27 12:59:16 -05:00
Chris Mason
45f49bce99 Btrfs: avoid NULL pointer deref in try_release_extent_buffer
If we fail to find a pointer in the radix tree, don't try
to deref the NULL one we do have.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-11-21 22:27:44 -05:00
Josef Bacik
a1b075d28d Btrfs: make btrfs_add_nondir take parent inode as an argument
Everybody who calls btrfs_add_nondir just passes in the dentry of the new file
and then dereference dentry->d_parent->d_inode, but everybody who calls
btrfs_add_nondir() are already passed the parent's inode.  So instead of
dereferencing dentry->d_parent, just make btrfs_add_nondir take the dir inode as
an argument and pass that along so we don't have to worry about d_parent.
Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-11-21 22:26:10 -05:00
Josef Bacik
495e86779f Btrfs: hold i_mutex when calling btrfs_log_dentry_safe
Since we walk up the path logging all of the parts of the inode's path, we need
to hold i_mutex to make sure that the inode is not renamed while we're logging
everything.  btrfs_log_dentry_safe does dget_parent and all of that jazz, but we
may get unexpected results if the rename changes the inode's location while
we're higher up the path logging those dentries, so do this for safety reasons.
Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-11-21 22:26:09 -05:00
Josef Bacik
6a91221304 Btrfs: use dget_parent where we can UPDATED
There are lots of places where we do dentry->d_parent->d_inode without holding
the dentry->d_lock.  This could cause problems with rename.  So instead we need
to use dget_parent() and hold the reference to the parent as long as we are
going to use it's inode and then dput it at the end.

Signed-off-by: Josef Bacik <josef@redhat.com>
Cc: raven@themaw.net
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-11-21 22:26:09 -05:00
Josef Bacik
7619585390 Btrfs: fix more ESTALE problems with NFS
When creating new inodes we don't setup inode->i_generation.  So if we generate
an fh with a newly created inode we save the generation of 0, but if we flush
the inode to disk and have to read it back when getting the inode on the server
we'll have the right i_generation, so gens wont match and we get ESTALE.  This
patch properly sets inode->i_generation when we create the new inode and now I'm
no longer getting ESTALE.  Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-11-21 22:26:08 -05:00
Josef Bacik
2ede0daf01 Btrfs: handle NFS lookups properly
People kept reporting NFS issues, specifically getting ESTALE alot.  I figured
out how to reproduce the problem

SERVER
mkfs.btrfs /dev/sda1
mount /dev/sda1 /mnt/btrfs-test
<add /mnt/btrfs-test to /etc/exports>
btrfs subvol create /mnt/btrfs-test/foo
service nfs start

CLIENT
mount server:/mnt/btrfs /mnt/test
cd /mnt/test/foo
ls

SERVER
echo 3 > /proc/sys/vm/drop_caches

CLIENT
ls			<-- get an ESTALE here

This is because the standard way to lookup a name in nfsd is to use readdir, and
what it does is do a readdir on the parent directory looking for the inode of
the child.  So in this case the parent being / and the child being foo.  Well
subvols all have the same inode number, so doing a readdir of / looking for
inode 256 will return '.', which obviously doesn't match foo.  So instead we
need to have our own .get_name so that we can find the right name.

Our .get_name will either lookup the inode backref or the root backref,
whichever we're looking for, and return the name we find.  Running the above
reproducer with this patch results in everything acting the way its supposed to.
Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-11-21 22:26:08 -05:00
Mariusz Kozlowski
0410c94aff btrfs: make 1-bit signed fileds unsigned
Fixes these sparse warnings:
fs/btrfs/ctree.h:811:17: error: dubious one-bit signed bitfield
fs/btrfs/ctree.h:812:20: error: dubious one-bit signed bitfield
fs/btrfs/ctree.h:813:19: error: dubious one-bit signed bitfield

Signed-off-by: Mariusz Kozlowski <mk@lab.zgora.pl>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-11-21 22:26:07 -05:00
Li Zefan
f209561ad8 btrfs: Show device attr correctly for symlinks
Symlinks and files of other types show different device numbers, though
they are on the same partition:

 $ touch tmp; ln -s tmp tmp2; stat tmp tmp2
   File: `tmp'
   Size: 0         	Blocks: 0          IO Block: 4096   regular empty file
 Device: 15h/21d	Inode: 984027      Links: 1
 --- snip ---
   File: `tmp2' -> `tmp'
   Size: 3         	Blocks: 0          IO Block: 4096   symbolic link
 Device: 13h/19d	Inode: 984028      Links: 1

Reported-by: Toke Høiland-Jørgensen <toke@toke.dk>
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-11-21 22:26:07 -05:00
Li Zefan
5f3888ff6f btrfs: Set file size correctly in file clone
Set src_offset = 0, src_length = 20K, dest_offset = 20K. And the
original filesize of the dest file 'file2' is 30K:

  # ls -l /mnt/file2
  -rw-r--r-- 1 root root 30720 Nov 18 16:42 /mnt/file2

Now clone file1 to file2, the dest file should be 40K, but it
still shows 30K:

  # ls -l /mnt/file2
  -rw-r--r-- 1 root root 30720 Nov 18 16:42 /mnt/file2

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-11-21 22:26:06 -05:00
Li Zefan
2a6b8daeda btrfs: Check if dest_offset is block-size aligned before cloning file
We've done the check for src_offset and src_length, and We should
also check dest_offset, otherwise we'll corrupt the destination
file:

  (After cloning file1 to file2 with unaligned dest_offset)
  # cat /mnt/file2
  cat: /mnt/file2: Input/output error

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-11-21 22:26:05 -05:00
Josef Bacik
0de90876c6 Btrfs: handle the space_cache option properly
When I added the clear_cache option I screwed up and took the break out of
the space_cache case statement, so whenever you mount with space_cache you also
get clear_cache, which does you no good if you say set space_cache in fstab so
it always gets set.  This patch adds the break back in properly.

Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-11-21 22:26:05 -05:00
Arne Jansen
6f33434850 btrfs: Fix early enospc because 'unused' calculated with wrong sign.
'unused' calculated with wrong sign in reserve_metadata_bytes().
This might have lead to unwanted over-reservations.

Signed-off-by: Arne Jansen <sensille@gmx.net>
Reviewed-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-11-21 22:26:04 -05:00
Miao Xie
e65e153554 btrfs: fix panic caused by direct IO
btrfs paniced when we write >64KB data by direct IO at one time.

Reproduce steps:
 # mkfs.btrfs /dev/sda5 /dev/sda6
 # mount /dev/sda5 /mnt
 # dd if=/dev/zero of=/mnt/tmpfile bs=100K count=1 oflag=direct

Then btrfs paniced:
mapping failed logical 1103155200 bio len 69632 len 12288
------------[ cut here ]------------
kernel BUG at fs/btrfs/volumes.c:3010!
[SNIP]
Pid: 1992, comm: btrfs-worker-0 Not tainted 2.6.37-rc1 #1 D2399/PRIMERGY
RIP: 0010:[<ffffffffa03d1462>]  [<ffffffffa03d1462>] btrfs_map_bio+0x202/0x210 [btrfs]
[SNIP]
Call Trace:
 [<ffffffffa03ab3eb>] __btrfs_submit_bio_done+0x1b/0x20 [btrfs]
 [<ffffffffa03a35ff>] run_one_async_done+0x9f/0xb0 [btrfs]
 [<ffffffffa03d3d20>] run_ordered_completions+0x80/0xc0 [btrfs]
 [<ffffffffa03d45a4>] worker_loop+0x154/0x5f0 [btrfs]
 [<ffffffffa03d4450>] ? worker_loop+0x0/0x5f0 [btrfs]
 [<ffffffffa03d4450>] ? worker_loop+0x0/0x5f0 [btrfs]
 [<ffffffff81083216>] kthread+0x96/0xa0
 [<ffffffff8100cec4>] kernel_thread_helper+0x4/0x10
 [<ffffffff81083180>] ? kthread+0x0/0xa0
 [<ffffffff8100cec0>] ? kernel_thread_helper+0x0/0x10

We fix this problem by splitting bios when we submit bios.

Reported-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Tested-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-11-21 22:26:04 -05:00
Miao Xie
88f794ede7 btrfs: cleanup duplicate bio allocating functions
extent_bio_alloc() and compressed_bio_alloc() are similar, cleanup
similar source code.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-11-21 22:26:03 -05:00
Miao Xie
0c56fa9662 btrfs: fix free dip and dip->csums twice
bio_endio() will free dip and dip->csums, so dip and dip->csums twice will
be freed twice. Fix it.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-11-21 22:26:02 -05:00
Chris Mason
784b4e29a2 Btrfs: add migrate page for metadata inode
Migrate page will directly call the btrfs btree writepage function,
which isn't actually allowed.

Our writepage assumes that you have locked the extent_buffer and
flagged the block as written.  Without doing these steps, we can
corrupt metadata blocks.

A later commit will remove the btree writepage function since
it is really only safely used internally by btrfs.  We
use writepages for everything else.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-11-21 22:26:02 -05:00
Tejun Heo
d4d7762995 block: clean up blkdev_get() wrappers and their users
After recent blkdev_get() modifications, open_by_devnum() and
open_bdev_exclusive() are simple wrappers around blkdev_get().
Replace them with blkdev_get_by_dev() and blkdev_get_by_path().

blkdev_get_by_dev() is identical to open_by_devnum().
blkdev_get_by_path() is slightly different in that it doesn't
automatically add %FMODE_EXCL to @mode.

All users are converted.  Most conversions are mechanical and don't
introduce any behavior difference.  There are several exceptions.

* btrfs now sets FMODE_EXCL in btrfs_device->mode, so there's no
  reason to OR it explicitly on blkdev_put().

* gfs2, nilfs2 and the generic mount_bdev() now set FMODE_EXCL in
  sb->s_mode.

* With the above changes, sb->s_mode now always should contain
  FMODE_EXCL.  WARN_ON_ONCE() added to kill_block_super() to detect
  errors.

The new blkdev_get_*() functions are with proper docbook comments.
While at it, add function description to blkdev_get() too.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Philipp Reisner <philipp.reisner@linbit.com>
Cc: Neil Brown <neilb@suse.de>
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: Joern Engel <joern@lazybastard.org>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: Jan Kara <jack@suse.cz>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: KONISHI Ryusuke <konishi.ryusuke@lab.ntt.co.jp>
Cc: reiserfs-devel@vger.kernel.org
Cc: xfs-masters@oss.sgi.com
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
2010-11-13 11:55:18 +01:00
Tejun Heo
e525fd89d3 block: make blkdev_get/put() handle exclusive access
Over time, block layer has accumulated a set of APIs dealing with bdev
open, close, claim and release.

* blkdev_get/put() are the primary open and close functions.

* bd_claim/release() deal with exclusive open.

* open/close_bdev_exclusive() are combination of open and claim and
  the other way around, respectively.

* bd_link/unlink_disk_holder() to create and remove holder/slave
  symlinks.

* open_by_devnum() wraps bdget() + blkdev_get().

The interface is a bit confusing and the decoupling of open and claim
makes it impossible to properly guarantee exclusive access as
in-kernel open + claim sequence can disturb the existing exclusive
open even before the block layer knows the current open if for another
exclusive access.  Reorganize the interface such that,

* blkdev_get() is extended to include exclusive access management.
  @holder argument is added and, if is @FMODE_EXCL specified, it will
  gain exclusive access atomically w.r.t. other exclusive accesses.

* blkdev_put() is similarly extended.  It now takes @mode argument and
  if @FMODE_EXCL is set, it releases an exclusive access.  Also, when
  the last exclusive claim is released, the holder/slave symlinks are
  removed automatically.

* bd_claim/release() and close_bdev_exclusive() are no longer
  necessary and either made static or removed.

* bd_link_disk_holder() remains the same but bd_unlink_disk_holder()
  is no longer necessary and removed.

* open_bdev_exclusive() becomes a simple wrapper around lookup_bdev()
  and blkdev_get().  It also has an unexpected extra bdev_read_only()
  test which probably should be moved into blkdev_get().

* open_by_devnum() is modified to take @holder argument and pass it to
  blkdev_get().

Most of bdev open/close operations are unified into blkdev_get/put()
and most exclusive accesses are tested atomically at the open time (as
it should).  This cleans up code and removes some, both valid and
invalid, but unnecessary all the same, corner cases.

open_bdev_exclusive() and open_by_devnum() can use further cleanup -
rename to blkdev_get_by_path() and blkdev_get_by_devt() and drop
special features.  Well, let's leave them for another day.

Most conversions are straight-forward.  drbd conversion is a bit more
involved as there was some reordering, but the logic should stay the
same.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Neil Brown <neilb@suse.de>
Acked-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Acked-by: Mike Snitzer <snitzer@redhat.com>
Acked-by: Philipp Reisner <philipp.reisner@linbit.com>
Cc: Peter Osterlund <petero2@telia.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <joel.becker@oracle.com>
Cc: Alex Elder <aelder@sgi.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: dm-devel@redhat.com
Cc: drbd-dev@lists.linbit.com
Cc: Leo Chen <leochen@broadcom.com>
Cc: Scott Branden <sbranden@broadcom.com>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
Cc: Joern Engel <joern@logfs.org>
Cc: reiserfs-devel@vger.kernel.org
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
2010-11-13 11:55:17 +01:00
Tejun Heo
37004c42f7 btrfs: close_bdev_exclusive() should use the same @flags as the matching open_bdev_exclusive()
In the failure path of __btrfs_open_devices(), close_bdev_exclusive()
is called with @flags which doesn't match the one used during
open_bdev_exclusive().  Fix it.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Chris Mason <chris.mason@oracle.com>
2010-11-13 11:55:17 +01:00
Linus Torvalds
925d169f5b Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable: (39 commits)
  Btrfs: deal with errors from updating the tree log
  Btrfs: allow subvol deletion by unprivileged user with -o user_subvol_rm_allowed
  Btrfs: make SNAP_DESTROY async
  Btrfs: add SNAP_CREATE_ASYNC ioctl
  Btrfs: add START_SYNC, WAIT_SYNC ioctls
  Btrfs: async transaction commit
  Btrfs: fix deadlock in btrfs_commit_transaction
  Btrfs: fix lockdep warning on clone ioctl
  Btrfs: fix clone ioctl where range is adjacent to extent
  Btrfs: fix delalloc checks in clone ioctl
  Btrfs: drop unused variable in block_alloc_rsv
  Btrfs: cleanup warnings from gcc 4.6 (nonbugs)
  Btrfs: Fix variables set but not read (bugs found by gcc 4.6)
  Btrfs: Use ERR_CAST helpers
  Btrfs: use memdup_user helpers
  Btrfs: fix raid code for removing missing drives
  Btrfs: Switch the extent buffer rbtree into a radix tree
  Btrfs: restructure try_release_extent_buffer()
  Btrfs: use the flusher threads for delalloc throttling
  Btrfs: tune the chunk allocation to 5% of the FS as metadata
  ...

Fix up trivial conflicts in fs/btrfs/super.c and fs/fs-writeback.c, and
remove use of INIT_RCU_HEAD in fs/btrfs/extent_io.c (that init macro was
useless and removed in commit 5e8067adfd: "rcu head remove init")
2010-10-30 09:05:48 -07:00
Chris Mason
6418c96107 Btrfs: deal with errors from updating the tree log
During unlink we remove any references to the inode from
the tree log.  It can return -ENOENT and other errors,
and this changes the unlink code to deal with it.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-10-30 07:34:24 -04:00
Sage Weil
4260f7c751 Btrfs: allow subvol deletion by unprivileged user with -o user_subvol_rm_allowed
Add a mount option user_subvol_rm_allowed that allows users to delete a
(potentially non-empty!) subvol when they would otherwise we allowed to do
an rmdir(2).  We duplicate the may_delete() checks from the core VFS code
to implement identical security checks (minus the directory size check).
We additionally require that the user has write+exec permission on the
subvol root inode.

Signed-off-by: Sage Weil <sage@newdream.net>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-10-29 21:42:10 -04:00
Sage Weil
531cb13f1e Btrfs: make SNAP_DESTROY async
There is no reason to force an immediate commit when deleting a snapshot.
Users have some expectation that space from a deleted snapshot be freed
immediately, but even if we do commit the reclaim is a background process.

If users _do_ want the deletion to be durable, they can call 'sync'.

Signed-off-by: Sage Weil <sage@newdream.net>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-10-29 21:42:10 -04:00
Sage Weil
72fd032e94 Btrfs: add SNAP_CREATE_ASYNC ioctl
Create a snap without waiting for it to commit to disk.  The ioctl is
ordered such that subsequent operations will not be contained by the
created snapshot, and the commit is initiated, but the ioctl does not
wait for the snapshot to commit to disk.

We return the specific transid to userspace so that an application can wait
for this specific snapshot creation to commit via the WAIT_SYNC ioctl.

Signed-off-by: Sage Weil <sage@newdream.net>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-10-29 21:41:57 -04:00
Sage Weil
462045928b Btrfs: add START_SYNC, WAIT_SYNC ioctls
START_SYNC will start a sync/commit, but not wait for it to
complete.  Any modification started after the ioctl returns is
guaranteed not to be included in the commit.  If a non-NULL
pointer is passed, the transaction id will be returned to
userspace.

WAIT_SYNC will wait for any in-progress commit to complete.  If a
transaction id is specified, the ioctl will block and then
return (success) when the specified transaction has committed.
If it has already committed when we call the ioctl, it returns
immediately.  If the specified transaction doesn't exist, it
returns EINVAL.

If no transaction id is specified, WAIT_SYNC will wait for the
currently committing transaction to finish it's commit to disk.
If there is no currently committing transaction, it returns
success.

These ioctls are useful for applications which want to impose an
ordering on when fs modifications reach disk, but do not want to
wait for the full (slow) commit process to do so.

Picky callers can take the transid returned by START_SYNC and
feed it to WAIT_SYNC, and be certain to wait only as long as
necessary for the transaction _they_ started to reach disk.

Sloppy callers can START_SYNC and WAIT_SYNC without a transid,
and provided they didn't wait too long between the calls, they
will get the same result.  However, if a second commit starts
before they call WAIT_SYNC, they may end up waiting longer for
it to commit as well.  Even so, a START_SYNC+WAIT_SYNC still
guarantees that any operation completed before the START_SYNC
reaches disk.

Signed-off-by: Sage Weil <sage@newdream.net>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-10-29 15:41:32 -04:00
Sage Weil
bb9c12c945 Btrfs: async transaction commit
Add support for an async transaction commit that is ordered such that any
subsequent operations will join the following transaction, but does not
wait until the current commit is fully on disk.  This avoids much of the
latency associated with the btrfs_commit_transaction for callers concerned
with serialization and not safety.

The wait_for_unblock flag controls whether we wait for the 'middle' portion
of commit_transaction to complete, which is necessary if the caller expects
some of the modifications contained in the commit to be available (this is
the case for subvol/snapshot creation).

Signed-off-by: Sage Weil <sage@newdream.net>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-10-29 15:37:34 -04:00
Sage Weil
99d16cbcaf Btrfs: fix deadlock in btrfs_commit_transaction
We calculate timeout (either 1 or MAX_SCHEDULE_TIMEOUT) based on whether
num_writers > 1 or should_grow at the top of the loop.  Then, much much
later, we wait for that timeout if either num_writers or should_grow is
true.  However, it's possible for a racing process (calling
btrfs_end_transaction()) to decrement num_writers such that we wait
forever instead of for 1.

Fix this by deciding how long to wait when we wait.  Include a smp_mb()
before checking if the waitqueue is active to ensure the num_writers
is visible.

Signed-off-by: Sage Weil <sage@newdream.net>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-10-29 15:37:34 -04:00
Sage Weil
fccdae435c Btrfs: fix lockdep warning on clone ioctl
I'm no lockdep expert, but this appears to make the lockdep warning go
away for the i_mutex locking in the clone ioctl.

Signed-off-by: Sage Weil <sage@newdream.net>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-10-29 15:37:33 -04:00
Sage Weil
050006a753 Btrfs: fix clone ioctl where range is adjacent to extent
We had an edge case issue where the requested range was just
following an existing extent. Instead of skipping to the next
extent, we used the previous one which lead to having zero
sized extents.

Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-10-29 15:37:33 -04:00
Sage Weil
9a019196ec Btrfs: fix delalloc checks in clone ioctl
The lookup_first_ordered_extent() was done on the wrong inode, and the
->delalloc_bytes test was wrong, as the following
btrfs_wait_ordered_range() would only invoke a range write and wouldn't
write the entire file data range. Also, a bad parameter was passed to
btrfs_wait_ordered_range().

Signed-off-by: Yehuda Sadeh <yehuda@hq.newdream.net>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-10-29 15:37:33 -04:00
Chris Mason
d8e39c457b Btrfs: drop unused variable in block_alloc_rsv
The alloc_target variable is not really used.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-10-29 15:17:41 -04:00
Andi Kleen
559af82114 Btrfs: cleanup warnings from gcc 4.6 (nonbugs)
These are all the cases where a variable is set, but not read which are
not bugs as far as I can see, but simply leftovers.

Still needs more review.

Found by gcc 4.6's new warnings

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Cc: Chris Mason <chris.mason@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-10-29 15:14:37 -04:00
Andi Kleen
411fc6bcef Btrfs: Fix variables set but not read (bugs found by gcc 4.6)
These are all the cases where a variable is set, but not
read which are really bugs.

- Couple of incorrect error handling fixed.
- One incorrect use of a allocation policy
- Some other things

Still needs more review.

Found by gcc 4.6's new warnings.

[akpm@linux-foundation.org: fix build.  Might have been bitrot]
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Cc: Chris Mason <chris.mason@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-10-29 15:14:31 -04:00
Julia Lawall
d0b678cb0a Btrfs: Use ERR_CAST helpers
Use ERR_CAST(x) rather than ERR_PTR(PTR_ERR(x)).  The former makes more
clear what is the purpose of the operation, which otherwise looks like a
no-op.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
type T;
T x;
identifier f;
@@

T f (...) { <+...
- ERR_PTR(PTR_ERR(x))
+ x
 ...+> }

@@
expression x;
@@

- ERR_PTR(PTR_ERR(x))
+ ERR_CAST(x)
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Cc: Chris Mason <chris.mason@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-10-29 15:14:23 -04:00
Julia Lawall
2354d08fe9 Btrfs: use memdup_user helpers
Use memdup_user when user data is immediately copied into the
allocated region.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
expression from,to,size,flag;
position p;
identifier l1,l2;
@@

-  to = \(kmalloc@p\|kzalloc@p\)(size,flag);
+  to = memdup_user(from,size);
   if (
-      to==NULL
+      IS_ERR(to)
                 || ...) {
   <+... when != goto l1;
-  -ENOMEM
+  PTR_ERR(to)
   ...+>
   }
-  if (copy_from_user(to, from, size) != 0) {
-    <+... when != goto l2;
-    -EFAULT
-    ...+>
-  }
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Cc: Chris Mason <chris.mason@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-10-29 15:14:18 -04:00
Chris Mason
18e503d695 Btrfs: fix raid code for removing missing drives
When btrfs is mounted in degraded mode, it has some internal structures
to track the missing devices.  This missing device is setup as readonly,
but the mapping code can get upset when we try to write to it.

This changes the mapping code to return -EIO instead of oops when we try
to write to the readonly device.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-10-29 11:25:46 -04:00
Miao Xie
19fe0a8b78 Btrfs: Switch the extent buffer rbtree into a radix tree
This patch reduces the CPU time spent in the extent buffer search by using the
radix tree instead of the rbtree and using the rcu lock instead of the spin
lock.

I did a quick test by the benchmark tool[1] and found the patch improve the
file creation/deletion performance problem that I have reported[2].

Before applying this patch:
Create files:
	Total files: 50000
	Total time: 0.971531
	Average time: 0.000019
Delete files:
	Total files: 50000
	Total time: 1.366761
	Average time: 0.000027

After applying this patch:
Create files:
	Total files: 50000
	Total time: 0.927455
	Average time: 0.000019
Delete files:
	Total files: 50000
	Total time: 1.292280
	Average time: 0.000026

[1] http://marc.info/?l=linux-btrfs&m=128212635122920&q=p3
[2] http://marc.info/?l=linux-btrfs&m=128212635122920&w=2

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-10-29 11:25:45 -04:00
Miao Xie
897ca6e9b4 Btrfs: restructure try_release_extent_buffer()
restructure try_release_extent_buffer() and write a function to release the
extent buffer. It will be used later.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-10-29 11:25:45 -04:00
Chris Mason
bf9022e06a Btrfs: use the flusher threads for delalloc throttling
We have a fairly complex set of loops around walking our list of
delalloc inodes when we find metadata delalloc space running low.
It doesn't work very well, can use large amounts of CPU and doesn't
do very efficient writeback.

This switches us to kick the bdi flusher threads instead.  All dirty
data in btrfs is accounted as delalloc data, so this is very similar
in terms of what it writes, but we're able to just kick off the IO
and wait for progress.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-10-29 11:25:36 -04:00
Chris Mason
e5bc245829 Btrfs: tune the chunk allocation to 5% of the FS as metadata
An earlier commit tried to keep us from allocating too many
empty metadata chunks.  It was somewhat too restrictive and could
lead to ENOSPC errors on empty filesystems.

This increases the limits to about 5% of the FS size, allowing more
metadata chunks to be preallocated.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-10-29 11:25:35 -04:00
Chris Mason
cb44921a09 Btrfs: don't loop forever on bad btree blocks
When btrfs discovers the generation number in a btree block is
incorrect, it can loop forever without forcing the RAID
code to try a valid mirror, and without returning EIO.

This changes things to properly kick out the EIO.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-10-29 09:31:30 -04:00
Chris Mason
6b5b817f10 Merge branch 'bug-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/josef/btrfs-work
Conflicts:
	fs/btrfs/extent-tree.c

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-10-29 09:27:49 -04:00
Josef Bacik
8216ef866d Btrfs: let the user know space caching is enabled
If you mount -o space_cache, the option will be persistent across mounts, but to
make sure the user knows that they did this, emit a message telling them if they
didn't mount with -o space_cache but the feature is still used.

Signed-off-by: Josef Bacik <josef@redhat.com>
2010-10-29 09:26:37 -04:00
Josef Bacik
88c2ba3b06 Btrfs: Add a clear_cache mount option
If something goes wrong with the free space cache we need a way to make sure
it's not loaded on mount and that it's cleared for everybody.  When you pass the
clear_cache option it will make it so all block groups are setup to be cleared,
which keeps them from being loaded and then they will be truncated when the
transaction is committed.  Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>
2010-10-29 09:26:36 -04:00