Commit Graph

720 Commits

Author SHA1 Message Date
David Sterba c5868f8362 btrfs: add GET_SUPPORTED_FEATURES to the control device ioctls
The control device is accessible when no filesystem is mounted and we
may want to query features supported by the module. This is already
possible using the sysfs files, this ioctl is for parity and
convenience.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-02-23 12:56:21 +01:00
David Sterba 11ea474f74 btrfs: remove error message from search ioctl for nonexistent tree
Let's remove the error message that appears when the tree_id is not
present. This can happen with the quota tree and has been observed in
practice. The applications are supposed to handle -ENOENT and we don't
need to report that in the system log as it's not a fatal error.

Reported-by: Vlastimil Babka <vbabka@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-02-23 12:54:48 +01:00
Deepa Dinamani 04b285f35e btrfs: Replace CURRENT_TIME by current_fs_time()
CURRENT_TIME macro is not appropriate for filesystems as it
doesn't use the right granularity for filesystem timestamps.
Use current_fs_time() instead.

Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Cc: Chris Mason <clm@fb.com>
Cc: Josef Bacik <jbacik@fb.com>
Cc: linux-btrfs@vger.kernel.org
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-02-18 11:46:03 +01:00
Byongho Lee ac1407ba24 btrfs: remove redundant error check
While running btrfs_mksubvol(), d_really_is_positive() is called twice.
First in btrfs_mksubvol() and second inside btrfs_may_create().  So I
remove the first one.

Signed-off-by: Byongho Lee <bhlee.kernel@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-02-18 11:35:27 +01:00
Linus Torvalds 27c9d772e5 Merge branch 'for-linus-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs fixes from Chris Mason:
 "This has a few fixes from Filipe, along with a readdir fix from Dave
  that we've been testing for some time"

* 'for-linus-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  btrfs: properly set the termination value of ctx->pos in readdir
  Btrfs: fix hang on extent buffer lock caused by the inode_paths ioctl
  Btrfs: remove no longer used function extent_read_full_page_nolock()
  Btrfs: fix page reading in extent_same ioctl leading to csum errors
  Btrfs: fix invalid page accesses in extent_same (dedup) ioctl
2016-02-12 09:21:28 -08:00
David Sterba 66722f7c05 btrfs: switch to kcalloc in btrfs_cmp_data_prepare
Kcalloc is functionally equivalent and does overflow checks.

Signed-off-by: David Sterba <dsterba@suse.com>
2016-02-11 15:19:39 +01:00
David Sterba fd95ef56b1 btrfs: extent same: use GFP_KERNEL for page array allocations
We can safely use GFP_KERNEL in the functions called from the ioctl
handlers. Here we can allocate up to 32k so less pressure to the
allocator could help.

Signed-off-by: David Sterba <dsterba@suse.com>
2016-02-11 15:19:39 +01:00
Filipe Manana 3131400230 Btrfs: fix page reading in extent_same ioctl leading to csum errors
In the extent_same ioctl, we were grabbing the pages (locked) and
attempting to read them without bothering about any concurrent IO
against them. That is, we were not checking for any ongoing ordered
extents nor waiting for them to complete, which leads to a race where
the extent_same() code gets a checksum verification error when it
reads the pages, producing a message like the following in dmesg
and making the operation fail to user space with -ENOMEM:

[18990.161265] BTRFS warning (device sdc): csum failed ino 259 off 495616 csum 685204116 expected csum 1515870868

Fix this by using btrfs_readpage() for reading the pages instead of
extent_read_full_page_nolock(), which waits for any concurrent ordered
extents to complete and locks the io range. Also do better error handling
and don't treat all failures as -ENOMEM, as that's clearly misleasing,
becoming identical to the checks and operation of prepare_uptodate_page().

The use of extent_read_full_page_nolock() was required before
commit f441460202 ("btrfs: fix deadlock with extent-same and readpage"),
as we had the range locked in an inode's io tree before attempting to
read the pages.

Fixes: f441460202 ("btrfs: fix deadlock with extent-same and readpage")
Cc: stable@vger.kernel.org   # 4.2+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
2016-02-03 19:27:10 +00:00
Filipe Manana e0bd70c67b Btrfs: fix invalid page accesses in extent_same (dedup) ioctl
In the extent_same ioctl we are getting the pages for the source and
target ranges and unlocking them immediately after, which is incorrect
because later we attempt to map them (with kmap_atomic) and access their
contents at btrfs_cmp_data(). When we do such access the pages might have
been relocated or removed from memory, which leads to an invalid memory
access. This issue is detected on a kernel with CONFIG_DEBUG_PAGEALLOC=y
which produces a trace like the following:

186736.677437] general protection fault: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
[186736.680382] Modules linked in: btrfs dm_flakey dm_mod ppdev xor raid6_pq sha256_generic hmac drbg ansi_cprng acpi_cpufreq evdev sg aesni_intel aes_x86_64
parport_pc ablk_helper tpm_tis psmouse parport i2c_piix4 tpm cryptd i2c_core lrw processor button serio_raw pcspkr gf128mul glue_helper loop autofs4 ext4
crc16 mbcache jbd2 sd_mod sr_mod cdrom ata_generic virtio_scsi ata_piix libata virtio_pci virtio_ring crc32c_intel scsi_mod e1000 virtio floppy [last
unloaded: btrfs]
[186736.681319] CPU: 13 PID: 10222 Comm: duperemove Tainted: G        W       4.4.0-rc6-btrfs-next-18+ #1
[186736.681319] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS by qemu-project.org 04/01/2014
[186736.681319] task: ffff880132600400 ti: ffff880362284000 task.ti: ffff880362284000
[186736.681319] RIP: 0010:[<ffffffff81264d00>]  [<ffffffff81264d00>] memcmp+0xb/0x22
[186736.681319] RSP: 0018:ffff880362287d70  EFLAGS: 00010287
[186736.681319] RAX: 000002c002468acf RBX: 0000000012345678 RCX: 0000000000000000
[186736.681319] RDX: 0000000000001000 RSI: 0005d129c5cf9000 RDI: 0005d129c5cf9000
[186736.681319] RBP: ffff880362287d70 R08: 0000000000000000 R09: 0000000000001000
[186736.681319] R10: ffff880000000000 R11: 0000000000000476 R12: 0000000000001000
[186736.681319] R13: ffff8802f91d4c88 R14: ffff8801f2a77830 R15: ffff880352e83e40
[186736.681319] FS:  00007f27b37fe700(0000) GS:ffff88043dda0000(0000) knlGS:0000000000000000
[186736.681319] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[186736.681319] CR2: 00007f27a406a000 CR3: 0000000217421000 CR4: 00000000001406e0
[186736.681319] Stack:
[186736.681319]  ffff880362287ea0 ffffffffa048d0bd 000000000009f000 0000000000001000
[186736.681319]  0100000000000000 ffff8801f2a77850 ffff8802f91d49b0 ffff880132600400
[186736.681319]  00000000000004f8 ffff8801c1efbe41 0000000000000000 0000000000000038
[186736.681319] Call Trace:
[186736.681319]  [<ffffffffa048d0bd>] btrfs_ioctl+0x24cb/0x2731 [btrfs]
[186736.681319]  [<ffffffff8108a8b0>] ? arch_local_irq_save+0x9/0xc
[186736.681319]  [<ffffffff8118b3d4>] ? rcu_read_unlock+0x3e/0x5d
[186736.681319]  [<ffffffff811822f8>] do_vfs_ioctl+0x42b/0x4ea
[186736.681319]  [<ffffffff8118b4f3>] ? __fget_light+0x62/0x71
[186736.681319]  [<ffffffff8118240e>] SyS_ioctl+0x57/0x79
[186736.681319]  [<ffffffff814872d7>] entry_SYSCALL_64_fastpath+0x12/0x6f
[186736.681319] Code: 0a 3c 6e 74 0d 3c 79 74 04 3c 59 75 0c c6 06 01 eb 03 c6 06 00 31 c0 eb 05 b8 ea ff ff ff 5d c3 55 31 c9 48 89 e5 48 39 d1 74 13 <0f> b6
04 0f 44 0f b6 04 0e 48 ff c1 44 29 c0 74 ea eb 02 31 c0

(gdb) list *(btrfs_ioctl+0x24cb)
0x5e0e1 is in btrfs_ioctl (fs/btrfs/ioctl.c:2972).
2967                    dst_addr = kmap_atomic(dst_page);
2968
2969                    flush_dcache_page(src_page);
2970                    flush_dcache_page(dst_page);
2971
2972                    if (memcmp(addr, dst_addr, cmp_len))
2973                            ret = BTRFS_SAME_DATA_DIFFERS;
2974
2975                    kunmap_atomic(addr);
2976                    kunmap_atomic(dst_addr);

So fix this by making sure we keep the pages locked and respect the same
locking order as everywhere else: get and lock the pages first and then
lock the range in the inode's io tree (like for example at
__btrfs_buffered_write() and extent_readpages()). If an ordered extent
is found after locking the range in the io tree, unlock the range,
unlock the pages, wait for the ordered extent to complete and repeat the
entire locking process until no overlapping ordered extents are found.

Cc: stable@vger.kernel.org   # 4.2+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
2016-02-03 19:27:09 +00:00
Chandan Rajendra 65bfa65807 Btrfs: btrfs_ioctl_clone: Truncate complete page after performing clone operation
In subpagesize-blocksize scenario, the "destination offset" argument passed to
the btrfs_ioctl_clone() can be aligned to sectorsize but may not be
necessarily aligned to the machine's page size. In such cases,
truncate_inode_pages_range() ends up zeroing out the partial page and future
read operations will return incorrect data. Hence this commit explicitly
rounds down the "destination offset" to the machine's page size.

Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-02-01 19:24:29 +01:00
Chris Mason e410e34fad Revert "btrfs: synchronize incompat feature bits with sysfs files"
This reverts commit 14e46e0495.

This ends up doing sysfs operations from deep in balance (where we
should be GFP_NOFS) and under heavy balance load, we're making races
against sysfs internals.

Revert it for now while we figure things out.

Signed-off-by: Chris Mason <clm@fb.com>
2016-01-29 08:19:37 -08:00
Chris Mason 6b5aa88c86 Merge branch 'fix/fst-sysfs' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux into for-linus-4.5
Signed-off-by: Chris Mason <clm@fb.com>
2016-01-25 16:43:13 -08:00
Al Viro 5955102c99 wrappers for ->i_mutex access
parallel to mutex_{lock,unlock,trylock,is_locked,lock_nested},
inode_foo(inode) being mutex_foo(&inode->i_mutex).

Please, use those for access to ->i_mutex; over the coming cycle
->i_mutex will become rwsem, with ->lookup() done with it held
only shared.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-01-22 18:04:28 -05:00
Linus Torvalds 2101ae4289 Merge branch 'for-linus-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull more btrfs updates from Chris Mason:
 "These are mostly fixes that we've been testing, but also we grabbed
  and tested a few small cleanups that had been on the list for a while.

  Zhao Lei's patchset also fixes some early ENOSPC buglets"

* 'for-linus-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (21 commits)
  btrfs: raid56: Use raid_write_end_io for scrub
  btrfs: Remove unnecessary ClearPageUptodate for raid56
  btrfs: use rbio->nr_pages to reduce calculation
  btrfs: Use unified stripe_page's index calculation
  btrfs: Fix calculation of rbio->dbitmap's size calculation
  btrfs: Fix no_space in write and rm loop
  btrfs: merge functions for wait snapshot creation
  btrfs: delete unused argument in btrfs_copy_from_user
  btrfs: Use direct way to determine raid56 write/recover mode
  btrfs: Small cleanup for get index_srcdev loop
  btrfs: Enhance chunk validation check
  btrfs: Enhance super validation check
  Btrfs: fix deadlock running delayed iputs at transaction commit time
  Btrfs: fix typo in log message when starting a balance
  btrfs: remove duplicate const specifier
  btrfs: initialize the seq counter in struct btrfs_device
  Btrfs: clean up an error code in btrfs_init_space_info()
  btrfs: fix iterator with update error in backref.c
  Btrfs: fix output of compression message in btrfs_parse_options()
  Btrfs: Initialize btrfs_root->highest_objectid when loading tree root and subvolume roots
  ...
2016-01-22 11:49:21 -08:00
David Sterba 14e46e0495 btrfs: synchronize incompat feature bits with sysfs files
The files under /sys/fs/UUID/features get out of sync with the actual
incompat bits set for the filesystem if they change after mount (eg. the
LZO compression).

Synchronize the feature bits with the sysfs files representing them
right after we set/clear them.

Signed-off-by: David Sterba <dsterba@suse.com>
2016-01-21 18:54:41 +01:00
Chris Mason 326f784281 Merge branch 'misc-for-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux into for-linus-4.5 2016-01-19 18:21:30 -08:00
Linus Torvalds c1a198d923 Merge branch 'for-linus-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs updates from Chris Mason:
 "This has our usual assortment of fixes and cleanups, but the biggest
  change included is Omar Sandoval's free space tree.  It's not the
  default yet, mounting -o space_cache=v2 enables it and sets a readonly
  compat bit.  The tree can actually be deleted and regenerated if there
  are any problems, but it has held up really well in testing so far.

  For very large filesystems (30T+) our existing free space caching code
  can end up taking a huge amount of time during commits.  The new tree
  based code is faster and less work overall to update as the commit
  progresses.

  Omar worked on this during the summer and we'll hammer on it in
  production here at FB over the next few months"

* 'for-linus-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (73 commits)
  Btrfs: fix fitrim discarding device area reserved for boot loader's use
  Btrfs: Check metadata redundancy on balance
  btrfs: statfs: report zero available if metadata are exhausted
  btrfs: preallocate path for snapshot creation at ioctl time
  btrfs: allocate root item at snapshot ioctl time
  btrfs: do an allocation earlier during snapshot creation
  btrfs: use smaller type for btrfs_path locks
  btrfs: use smaller type for btrfs_path lowest_level
  btrfs: use smaller type for btrfs_path reada
  btrfs: cleanup, use enum values for btrfs_path reada
  btrfs: constify static arrays
  btrfs: constify remaining structs with function pointers
  btrfs tests: replace whole ops structure for free space tests
  btrfs: use list_for_each_entry* in backref.c
  btrfs: use list_for_each_entry_safe in free-space-cache.c
  btrfs: use list_for_each_entry* in check-integrity.c
  Btrfs: use linux/sizes.h to represent constants
  btrfs: cleanup, remove stray return statements
  btrfs: zero out delayed node upon allocation
  btrfs: pass proper enum type to start_transaction()
  ...
2016-01-18 12:44:40 -08:00
Chandan Rajendra f32e48e925 Btrfs: Initialize btrfs_root->highest_objectid when loading tree root and subvolume roots
The following call trace is seen when btrfs/031 test is executed in a loop,

[  158.661848] ------------[ cut here ]------------
[  158.662634] WARNING: CPU: 2 PID: 890 at /home/chandan/repos/linux/fs/btrfs/ioctl.c:558 create_subvol+0x3d1/0x6ea()
[  158.664102] BTRFS: Transaction aborted (error -2)
[  158.664774] Modules linked in:
[  158.665266] CPU: 2 PID: 890 Comm: btrfs Not tainted 4.4.0-rc6-g511711a #2
[  158.666251] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
[  158.667392]  ffffffff81c0a6b0 ffff8806c7c4f8e8 ffffffff81431fc8 ffff8806c7c4f930
[  158.668515]  ffff8806c7c4f920 ffffffff81051aa1 ffff880c85aff000 ffff8800bb44d000
[  158.669647]  ffff8808863b5c98 0000000000000000 00000000fffffffe ffff8806c7c4f980
[  158.670769] Call Trace:
[  158.671153]  [<ffffffff81431fc8>] dump_stack+0x44/0x5c
[  158.671884]  [<ffffffff81051aa1>] warn_slowpath_common+0x81/0xc0
[  158.672769]  [<ffffffff81051b27>] warn_slowpath_fmt+0x47/0x50
[  158.673620]  [<ffffffff813bc98d>] create_subvol+0x3d1/0x6ea
[  158.674440]  [<ffffffff813777c9>] btrfs_mksubvol.isra.30+0x369/0x520
[  158.675376]  [<ffffffff8108a4aa>] ? percpu_down_read+0x1a/0x50
[  158.676235]  [<ffffffff81377a81>] btrfs_ioctl_snap_create_transid+0x101/0x180
[  158.677268]  [<ffffffff81377b52>] btrfs_ioctl_snap_create+0x52/0x70
[  158.678183]  [<ffffffff8137afb4>] btrfs_ioctl+0x474/0x2f90
[  158.678975]  [<ffffffff81144b8e>] ? vma_merge+0xee/0x300
[  158.679751]  [<ffffffff8115be31>] ? alloc_pages_vma+0x91/0x170
[  158.680599]  [<ffffffff81123f62>] ? lru_cache_add_active_or_unevictable+0x22/0x70
[  158.681686]  [<ffffffff813d99cf>] ? selinux_file_ioctl+0xff/0x1d0
[  158.682581]  [<ffffffff8117b791>] do_vfs_ioctl+0x2c1/0x490
[  158.683399]  [<ffffffff813d3cde>] ? security_file_ioctl+0x3e/0x60
[  158.684297]  [<ffffffff8117b9d4>] SyS_ioctl+0x74/0x80
[  158.685051]  [<ffffffff819b2bd7>] entry_SYSCALL_64_fastpath+0x12/0x6a
[  158.685958] ---[ end trace 4b63312de5a2cb76 ]---
[  158.686647] BTRFS: error (device loop0) in create_subvol:558: errno=-2 No such entry
[  158.709508] BTRFS info (device loop0): forced readonly
[  158.737113] BTRFS info (device loop0): disk space caching is enabled
[  158.738096] BTRFS error (device loop0): Remounting read-write after error is not allowed
[  158.851303] BTRFS error (device loop0): cleaner transaction attach returned -30

This occurs because,

Mount filesystem
Create subvol with ID 257
Unmount filesystem
Mount filesystem
Delete subvol with ID 257
  btrfs_drop_snapshot()
    Add root corresponding to subvol 257 into
    btrfs_transaction->dropped_roots list
Create new subvol (i.e. create_subvol())
  257 is returned as the next free objectid
  btrfs_read_fs_root_no_name()
    Finds the btrfs_root instance corresponding to the old subvol with ID 257
    in btrfs_fs_info->fs_roots_radix.
    Returns error since btrfs_root_item->refs has the value of 0.

To fix the issue the commit initializes tree root's and subvolume root's
highest_objectid when loading the roots from disk.

Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-01-15 19:25:02 +01:00
Chris Mason b28cf57246 Merge branch 'misc-cleanups-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux into for-linus-4.5
Signed-off-by: Chris Mason <clm@fb.com>
2016-01-11 06:08:37 -08:00
Chris Mason a3058101c1 Merge branch 'misc-for-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux into for-linus-4.5 2016-01-11 05:59:32 -08:00
David Sterba 8546b57051 btrfs: preallocate path for snapshot creation at ioctl time
We can also preallocate btrfs_path that's used during pending snapshot
creation and avoid another late ENOMEM failure.

Signed-off-by: David Sterba <dsterba@suse.com>
2016-01-07 15:20:55 +01:00
David Sterba b0c0ea6338 btrfs: allocate root item at snapshot ioctl time
The actual snapshot creation is delayed until transaction commit. If we
cannot get enough memory for the root item there, we have to fail the
whole transaction commit which is bad. So we'll allocate the memory at
the ioctl call and pass it along with the pending_snapshot struct. The
potential ENOMEM will be returned to the caller of snapshot ioctl.

Signed-off-by: David Sterba <dsterba@suse.com>
2016-01-07 15:20:54 +01:00
David Sterba a1ee736268 btrfs: do an allocation earlier during snapshot creation
We can allocate pending_snapshot earlier and do not have to do cleanup
in case of failure.

Signed-off-by: David Sterba <dsterba@suse.com>
2016-01-07 15:20:54 +01:00
David Sterba e4058b54d1 btrfs: cleanup, use enum values for btrfs_path reada
Replace the integers by enums for better readability. The value 2 does
not have any meaning since a717531942
"Btrfs: do less aggressive btree readahead" (2009-01-22).

Signed-off-by: David Sterba <dsterba@suse.com>
2016-01-07 15:01:15 +01:00
David Sterba 4d4ab6d6bc btrfs: constify static arrays
There are a few statically initialized arrays that can be made const.
The remaining (like file_system_type, sysfs attributes or prop handlers)
do not allow that due to type mismatch when passed to the APIs or
because the structures are modified through other members.

Signed-off-by: David Sterba <dsterba@suse.com>
2016-01-07 15:01:15 +01:00
Byongho Lee ee22184b53 Btrfs: use linux/sizes.h to represent constants
We use many constants to represent size and offset value.  And to make
code readable we use '256 * 1024 * 1024' instead of '268435456' to
represent '256MB'.  However we can make far more readable with 'SZ_256MB'
which is defined in the 'linux/sizes.h'.

So this patch replaces 'xxx * 1024 * 1024' kind of expression with
single 'SZ_xxxMB' if 'xxx' is a power of 2 then 'xxx * SZ_1M' if 'xxx' is
not a power of 2. And I haven't touched to '4096' & '8192' because it's
more intuitive than 'SZ_4KB' & 'SZ_8KB'.

Signed-off-by: Byongho Lee <bhlee.kernel@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2016-01-07 14:38:02 +01:00
Darrick J. Wong 2b3909f8a7 btrfs: use new dedupe data function pointer
Now that the VFS encapsulates the dedupe ioctl, wire up btrfs to it.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-01-01 02:36:40 -05:00
Chris Mason bb9d687618 Merge branch 'dev/simplify-set-bit' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux into for-linus-4.5
Signed-off-by: Chris Mason <clm@fb.com>
2015-12-23 13:17:42 -08:00
Christoph Hellwig 04b38d6012 vfs: pull btrfs clone API to vfs layer
The btrfs clone ioctls are now adopted by other file systems, with NFS
and CIFS already having support for them, and XFS being under active
development.  To avoid growth of various slightly incompatible
implementations, add one to the VFS.  Note that clones are different from
file copies in several ways:

 - they are atomic vs other writers
 - they support whole file clones
 - they support 64-bit legth clones
 - they do not allow partial success (aka short writes)
 - clones are expected to be a fast metadata operation

Because of that it would be rather cumbersome to try to piggyback them on
top of the recent clone_file_range infrastructure.  The converse isn't
true and the clone_file_range system call could try clone file range as
a first attempt to copy, something that further patches will enable.

Based on earlier work from Peng Tao.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-12-07 23:11:33 -05:00
David Sterba 8d2db7855e btrfs: use GFP_KERNEL for allocations in ioctl handlers
We don't have to use GFP_NOFS in the ioctl handlers because there's no
risk of looping through the allocators back to the filesystem. This
patch covers only allocations that are directly in the ioctl handlers.

Signed-off-by: David Sterba <dsterba@suse.com>
2015-12-03 15:03:43 +01:00
David Sterba ff13db41f1 btrfs: drop unused parameter from lock_extent_bits
We've always passed 0. Stack usage will slightly decrease.

Signed-off-by: David Sterba <dsterba@suse.com>
2015-12-03 14:30:40 +01:00
Zach Brown 3db11b2eec btrfs: add .copy_file_range file operation
This rearranges the existing COPY_RANGE ioctl implementation so that the
.copy_file_range file operation can call the core loop that copies file
data extent items.

The extent copying loop is lifted up into its own function.  It retains
the core btrfs error checks that should be shared.

Signed-off-by: Zach Brown <zab@redhat.com>
[Anna Schumaker: Make flags an unsigned int,
                 Check for COPY_FR_REFLINK]
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-12-01 14:00:54 -05:00
Linus Torvalds 27eb427bdc Merge branch 'for-linus-4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs updates from Chris Mason:
 "We have a lot of subvolume quota improvements in here, along with big
  piles of cleanups from Dave Sterba and Anand Jain and others.

  Josef pitched in a batch of allocator fixes based on production use
  here at FB.  We found that mount -o ssd_spread greatly improved our
  performance on hardware raid5/6, but it exposed some CPU bottlenecks
  in the allocator.  These patches make a huge difference"

* 'for-linus-4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (100 commits)
  Btrfs: fix hole punching when using the no-holes feature
  Btrfs: find_free_extent: Do not erroneously skip LOOP_CACHING_WAIT state
  btrfs: Fix a data space underflow warning
  btrfs: qgroup: Fix a rebase bug which will cause qgroup double free
  btrfs: qgroup: Fix a race in delayed_ref which leads to abort trans
  btrfs: clear PF_NOFREEZE in cleaner_kthread()
  btrfs: qgroup: Don't copy extent buffer to do qgroup rescan
  btrfs: add balance filters limits, stripes and usage to supported mask
  btrfs: extend balance filter usage to take minimum and maximum
  btrfs: add balance filter for stripes
  btrfs: extend balance filter limit to take minimum and maximum
  btrfs: fix use after free iterating extrefs
  btrfs: check unsupported filters in balance arguments
  Btrfs: fix regression running delayed references when using qgroups
  Btrfs: fix regression when running delayed references
  Btrfs: don't do extra bitmap search in one bit case
  Btrfs: keep track of largest extent in bitmaps
  Btrfs: don't keep trying to build clusters if we are fragmented
  Btrfs: cut down on loops through the allocator
  Btrfs: don't continue setting up space cache when enospc
  ...
2015-11-06 17:17:13 -08:00
David Sterba 849ef9286f btrfs: check unsupported filters in balance arguments
We don't verify that all the balance filter arguments supplemented by
the flags are actually known to the kernel. Thus we let it silently pass
and do nothing.

At the moment this means only the 'limit' filter, but we're going to add
a few more soon so it's better to have that fixed. Also in older stable
kernels so that it works with newer userspace tools.

Cc: stable@vger.kernel.org # 3.16+
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-10-26 19:38:26 -07:00
Filipe Manana b06c4bf5c8 Btrfs: fix regression running delayed references when using qgroups
In the kernel 4.2 merge window we had a big changes to the implementation
of delayed references and qgroups which made the no_quota field of delayed
references not used anymore. More specifically the no_quota field is not
used anymore as of:

  commit 0ed4792af0 ("btrfs: qgroup: Switch to new extent-oriented qgroup mechanism.")

Leaving the no_quota field actually prevents delayed references from
getting merged, which in turn cause the following BUG_ON(), at
fs/btrfs/extent-tree.c, to be hit when qgroups are enabled:

  static int run_delayed_tree_ref(...)
  {
     (...)
     BUG_ON(node->ref_mod != 1);
     (...)
  }

This happens on a scenario like the following:

  1) Ref1 bytenr X, action = BTRFS_ADD_DELAYED_REF, no_quota = 1, added.

  2) Ref2 bytenr X, action = BTRFS_DROP_DELAYED_REF, no_quota = 0, added.
     It's not merged with Ref1 because Ref1->no_quota != Ref2->no_quota.

  3) Ref3 bytenr X, action = BTRFS_ADD_DELAYED_REF, no_quota = 1, added.
     It's not merged with the reference at the tail of the list of refs
     for bytenr X because the reference at the tail, Ref2 is incompatible
     due to Ref2->no_quota != Ref3->no_quota.

  4) Ref4 bytenr X, action = BTRFS_DROP_DELAYED_REF, no_quota = 0, added.
     It's not merged with the reference at the tail of the list of refs
     for bytenr X because the reference at the tail, Ref3 is incompatible
     due to Ref3->no_quota != Ref4->no_quota.

  5) We run delayed references, trigger merging of delayed references,
     through __btrfs_run_delayed_refs() -> btrfs_merge_delayed_refs().

  6) Ref1 and Ref3 are merged as Ref1->no_quota = Ref3->no_quota and
     all other conditions are satisfied too. So Ref1 gets a ref_mod
     value of 2.

  7) Ref2 and Ref4 are merged as Ref2->no_quota = Ref4->no_quota and
     all other conditions are satisfied too. So Ref2 gets a ref_mod
     value of 2.

  8) Ref1 and Ref2 aren't merged, because they have different values
     for their no_quota field.

  9) Delayed reference Ref1 is picked for running (select_delayed_ref()
     always prefers references with an action == BTRFS_ADD_DELAYED_REF).
     So run_delayed_tree_ref() is called for Ref1 which triggers the
     BUG_ON because Ref1->red_mod != 1 (equals 2).

So fix this by removing the no_quota field, as it's not used anymore as
of commit 0ed4792af0 ("btrfs: qgroup: Switch to new extent-oriented
qgroup mechanism.").

The use of no_quota was also buggy in at least two places:

1) At delayed-refs.c:btrfs_add_delayed_tree_ref() - we were setting
   no_quota to 0 instead of 1 when the following condition was true:
   is_fstree(ref_root) || !fs_info->quota_enabled

2) At extent-tree.c:__btrfs_inc_extent_ref() - we were attempting to
   reset a node's no_quota when the condition "!is_fstree(root_objectid)
   || !root->fs_info->quota_enabled" was true but we did it only in
   an unused local stack variable, that is, we never reset the no_quota
   value in the node itself.

This fixes the remainder of problems several people have been having when
running delayed references, mostly while a balance is running in parallel,
on a 4.2+ kernel.

Very special thanks to Stéphane Lesimple for helping debugging this issue
and testing this fix on his multi terabyte filesystem (which took more
than one day to balance alone, plus fsck, etc).

Also, this fixes deadlock issue when using the clone ioctl with qgroups
enabled, as reported by Elias Probst in the mailing list. The deadlock
happens because after calling btrfs_insert_empty_item we have our path
holding a write lock on a leaf of the fs/subvol tree and then before
releasing the path we called check_ref() which did backref walking, when
qgroups are enabled, and tried to read lock the same leaf. The trace for
this case is the following:

  INFO: task systemd-nspawn:6095 blocked for more than 120 seconds.
  (...)
  Call Trace:
    [<ffffffff86999201>] schedule+0x74/0x83
    [<ffffffff863ef64c>] btrfs_tree_read_lock+0xc0/0xea
    [<ffffffff86137ed7>] ? wait_woken+0x74/0x74
    [<ffffffff8639f0a7>] btrfs_search_old_slot+0x51a/0x810
    [<ffffffff863a129b>] btrfs_next_old_leaf+0xdf/0x3ce
    [<ffffffff86413a00>] ? ulist_add_merge+0x1b/0x127
    [<ffffffff86411688>] __resolve_indirect_refs+0x62a/0x667
    [<ffffffff863ef546>] ? btrfs_clear_lock_blocking_rw+0x78/0xbe
    [<ffffffff864122d3>] find_parent_nodes+0xaf3/0xfc6
    [<ffffffff86412838>] __btrfs_find_all_roots+0x92/0xf0
    [<ffffffff864128f2>] btrfs_find_all_roots+0x45/0x65
    [<ffffffff8639a75b>] ? btrfs_get_tree_mod_seq+0x2b/0x88
    [<ffffffff863e852e>] check_ref+0x64/0xc4
    [<ffffffff863e9e01>] btrfs_clone+0x66e/0xb5d
    [<ffffffff863ea77f>] btrfs_ioctl_clone+0x48f/0x5bb
    [<ffffffff86048a68>] ? native_sched_clock+0x28/0x77
    [<ffffffff863ed9b0>] btrfs_ioctl+0xabc/0x25cb
  (...)

The problem goes away by eleminating check_ref(), which no longer is
needed as its purpose was to get a value for the no_quota field of
a delayed reference (this patch removes the no_quota field as mentioned
earlier).

Reported-by: Stéphane Lesimple <stephane_btrfs@lesimple.fr>
Tested-by: Stéphane Lesimple <stephane_btrfs@lesimple.fr>
Reported-by: Elias Probst <mail@eliasprobst.eu>
Reported-by: Peter Becker <floyd.net@gmail.com>
Reported-by: Malte Schröder <malte@tnxip.de>
Reported-by: Derek Dongray <derek@valedon.co.uk>
Reported-by: Erkki Seppala <flux-btrfs@inside.org>
Cc: stable@vger.kernel.org  # 4.2+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
2015-10-25 19:53:26 +00:00
Qu Wenruo 7cf5b97650 btrfs: qgroup: Cleanup old inaccurate facilities
Cleanup the old facilities which use old btrfs_qgroup_reserve() function
call, replace them with the newer version, and remove the "__" prefix in
them.

Also, make btrfs_qgroup_reserve/free() functions private, as they are
now only used inside qgroup codes.

Now, the whole btrfs qgroup is swithed to use the new reserve facilities.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-10-21 18:41:06 -07:00
Qu Wenruo df480633b8 btrfs: extent-tree: Switch to new delalloc space reserve and release
Use new __btrfs_delalloc_reserve_space() and
__btrfs_delalloc_release_space() to reserve and release space for
delalloc.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-10-21 18:41:05 -07:00
Chris Mason a408365c62 Merge branch 'integration-4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/fdmanana/linux into for-linus-4.4 2015-10-21 18:23:59 -07:00
Chris Mason a0d58e48db Merge branch 'cleanups/for-4.4' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux into for-linus-4.4 2015-10-21 18:21:40 -07:00
Christian Engelmayer 0f89abf56a btrfs: fix possible leak in btrfs_ioctl_balance()
Commit 8eb934591f ("btrfs: check unsupported filters in balance
arguments") adds a jump to exit label out_bargs in case the argument
check fails. At this point in addition to the bargs memory, the
memory for struct btrfs_balance_control has already been allocated.
Ownership of bctl is passed to btrfs_balance() in the good case,
thus the memory is not freed due to the introduced jump. Make sure
that the memory gets freed in any case as necessary. Detected by
Coverity CID 1328378.

Signed-off-by: Christian Engelmayer <cengelma@gmx.at>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-10-21 18:10:02 -07:00
Byongho Lee d7641a49a5 btrfs: replace unnecessary list_for_each_entry_safe to list_for_each_entry
There is no removing list element while iterating over list.
So, replace list_for_each_entry_safe to list_for_each_entry.

Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: Byongho Lee <bhlee.kernel@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2015-10-21 18:28:48 +02:00
Filipe Manana 8039d87d9e Btrfs: fix file corruption and data loss after cloning inline extents
Currently the clone ioctl allows to clone an inline extent from one file
to another that already has other (non-inlined) extents. This is a problem
because btrfs is not designed to deal with files having inline and regular
extents, if a file has an inline extent then it must be the only extent
in the file and must start at file offset 0. Having a file with an inline
extent followed by regular extents results in EIO errors when doing reads
or writes against the first 4K of the file.

Also, the clone ioctl allows one to lose data if the source file consists
of a single inline extent, with a size of N bytes, and the destination
file consists of a single inline extent with a size of M bytes, where we
have M > N. In this case the clone operation removes the inline extent
from the destination file and then copies the inline extent from the
source file into the destination file - we lose the M - N bytes from the
destination file, a read operation will get the value 0x00 for any bytes
in the the range [N, M] (the destination inode's i_size remained as M,
that's why we can read past N bytes).

So fix this by not allowing such destructive operations to happen and
return errno EOPNOTSUPP to user space.

Currently the fstest btrfs/035 tests the data loss case but it totally
ignores this - i.e. expects the operation to succeed and does not check
the we got data loss.

The following test case for fstests exercises all these cases that result
in file corruption and data loss:

  seq=`basename $0`
  seqres=$RESULT_DIR/$seq
  echo "QA output created by $seq"
  tmp=/tmp/$$
  status=1	# failure is the default!
  trap "_cleanup; exit \$status" 0 1 2 3 15

  _cleanup()
  {
      rm -f $tmp.*
  }

  # get standard environment, filters and checks
  . ./common/rc
  . ./common/filter

  # real QA test starts here
  _need_to_be_root
  _supported_fs btrfs
  _supported_os Linux
  _require_scratch
  _require_cloner
  _require_btrfs_fs_feature "no_holes"
  _require_btrfs_mkfs_feature "no-holes"

  rm -f $seqres.full

  test_cloning_inline_extents()
  {
      local mkfs_opts=$1
      local mount_opts=$2

      _scratch_mkfs $mkfs_opts >>$seqres.full 2>&1
      _scratch_mount $mount_opts

      # File bar, the source for all the following clone operations, consists
      # of a single inline extent (50 bytes).
      $XFS_IO_PROG -f -c "pwrite -S 0xbb 0 50" $SCRATCH_MNT/bar \
          | _filter_xfs_io

      # Test cloning into a file with an extent (non-inlined) where the
      # destination offset overlaps that extent. It should not be possible to
      # clone the inline extent from file bar into this file.
      $XFS_IO_PROG -f -c "pwrite -S 0xaa 0K 16K" $SCRATCH_MNT/foo \
          | _filter_xfs_io
      $CLONER_PROG -s 0 -d 0 -l 0 $SCRATCH_MNT/bar $SCRATCH_MNT/foo

      # Doing IO against any range in the first 4K of the file should work.
      # Due to a past clone ioctl bug which allowed cloning the inline extent,
      # these operations resulted in EIO errors.
      echo "File foo data after clone operation:"
      # All bytes should have the value 0xaa (clone operation failed and did
      # not modify our file).
      od -t x1 $SCRATCH_MNT/foo
      $XFS_IO_PROG -c "pwrite -S 0xcc 0 100" $SCRATCH_MNT/foo | _filter_xfs_io

      # Test cloning the inline extent against a file which has a hole in its
      # first 4K followed by a non-inlined extent. It should not be possible
      # as well to clone the inline extent from file bar into this file.
      $XFS_IO_PROG -f -c "pwrite -S 0xdd 4K 12K" $SCRATCH_MNT/foo2 \
          | _filter_xfs_io
      $CLONER_PROG -s 0 -d 0 -l 0 $SCRATCH_MNT/bar $SCRATCH_MNT/foo2

      # Doing IO against any range in the first 4K of the file should work.
      # Due to a past clone ioctl bug which allowed cloning the inline extent,
      # these operations resulted in EIO errors.
      echo "File foo2 data after clone operation:"
      # All bytes should have the value 0x00 (clone operation failed and did
      # not modify our file).
      od -t x1 $SCRATCH_MNT/foo2
      $XFS_IO_PROG -c "pwrite -S 0xee 0 90" $SCRATCH_MNT/foo2 | _filter_xfs_io

      # Test cloning the inline extent against a file which has a size of zero
      # but has a prealloc extent. It should not be possible as well to clone
      # the inline extent from file bar into this file.
      $XFS_IO_PROG -f -c "falloc -k 0 1M" $SCRATCH_MNT/foo3 | _filter_xfs_io
      $CLONER_PROG -s 0 -d 0 -l 0 $SCRATCH_MNT/bar $SCRATCH_MNT/foo3

      # Doing IO against any range in the first 4K of the file should work.
      # Due to a past clone ioctl bug which allowed cloning the inline extent,
      # these operations resulted in EIO errors.
      echo "First 50 bytes of foo3 after clone operation:"
      # Should not be able to read any bytes, file has 0 bytes i_size (the
      # clone operation failed and did not modify our file).
      od -t x1 $SCRATCH_MNT/foo3
      $XFS_IO_PROG -c "pwrite -S 0xff 0 90" $SCRATCH_MNT/foo3 | _filter_xfs_io

      # Test cloning the inline extent against a file which consists of a
      # single inline extent that has a size not greater than the size of
      # bar's inline extent (40 < 50).
      # It should be possible to do the extent cloning from bar to this file.
      $XFS_IO_PROG -f -c "pwrite -S 0x01 0 40" $SCRATCH_MNT/foo4 \
          | _filter_xfs_io
      $CLONER_PROG -s 0 -d 0 -l 0 $SCRATCH_MNT/bar $SCRATCH_MNT/foo4

      # Doing IO against any range in the first 4K of the file should work.
      echo "File foo4 data after clone operation:"
      # Must match file bar's content.
      od -t x1 $SCRATCH_MNT/foo4
      $XFS_IO_PROG -c "pwrite -S 0x02 0 90" $SCRATCH_MNT/foo4 | _filter_xfs_io

      # Test cloning the inline extent against a file which consists of a
      # single inline extent that has a size greater than the size of bar's
      # inline extent (60 > 50).
      # It should not be possible to clone the inline extent from file bar
      # into this file.
      $XFS_IO_PROG -f -c "pwrite -S 0x03 0 60" $SCRATCH_MNT/foo5 \
          | _filter_xfs_io
      $CLONER_PROG -s 0 -d 0 -l 0 $SCRATCH_MNT/bar $SCRATCH_MNT/foo5

      # Reading the file should not fail.
      echo "File foo5 data after clone operation:"
      # Must have a size of 60 bytes, with all bytes having a value of 0x03
      # (the clone operation failed and did not modify our file).
      od -t x1 $SCRATCH_MNT/foo5

      # Test cloning the inline extent against a file which has no extents but
      # has a size greater than bar's inline extent (16K > 50).
      # It should not be possible to clone the inline extent from file bar
      # into this file.
      $XFS_IO_PROG -f -c "truncate 16K" $SCRATCH_MNT/foo6 | _filter_xfs_io
      $CLONER_PROG -s 0 -d 0 -l 0 $SCRATCH_MNT/bar $SCRATCH_MNT/foo6

      # Reading the file should not fail.
      echo "File foo6 data after clone operation:"
      # Must have a size of 16K, with all bytes having a value of 0x00 (the
      # clone operation failed and did not modify our file).
      od -t x1 $SCRATCH_MNT/foo6

      # Test cloning the inline extent against a file which has no extents but
      # has a size not greater than bar's inline extent (30 < 50).
      # It should be possible to clone the inline extent from file bar into
      # this file.
      $XFS_IO_PROG -f -c "truncate 30" $SCRATCH_MNT/foo7 | _filter_xfs_io
      $CLONER_PROG -s 0 -d 0 -l 0 $SCRATCH_MNT/bar $SCRATCH_MNT/foo7

      # Reading the file should not fail.
      echo "File foo7 data after clone operation:"
      # Must have a size of 50 bytes, with all bytes having a value of 0xbb.
      od -t x1 $SCRATCH_MNT/foo7

      # Test cloning the inline extent against a file which has a size not
      # greater than the size of bar's inline extent (20 < 50) but has
      # a prealloc extent that goes beyond the file's size. It should not be
      # possible to clone the inline extent from bar into this file.
      $XFS_IO_PROG -f -c "falloc -k 0 1M" \
                      -c "pwrite -S 0x88 0 20" \
                      $SCRATCH_MNT/foo8 | _filter_xfs_io
      $CLONER_PROG -s 0 -d 0 -l 0 $SCRATCH_MNT/bar $SCRATCH_MNT/foo8

      echo "File foo8 data after clone operation:"
      # Must have a size of 20 bytes, with all bytes having a value of 0x88
      # (the clone operation did not modify our file).
      od -t x1 $SCRATCH_MNT/foo8

      _scratch_unmount
  }

  echo -e "\nTesting without compression and without the no-holes feature...\n"
  test_cloning_inline_extents

  echo -e "\nTesting with compression and without the no-holes feature...\n"
  test_cloning_inline_extents "" "-o compress"

  echo -e "\nTesting without compression and with the no-holes feature...\n"
  test_cloning_inline_extents "-O no-holes" ""

  echo -e "\nTesting with compression and with the no-holes feature...\n"
  test_cloning_inline_extents "-O no-holes" "-o compress"

  status=0
  exit

Cc: stable@vger.kernel.org
Signed-off-by: Filipe Manana <fdmanana@suse.com>
2015-10-14 04:36:43 +01:00
David Sterba 8eb934591f btrfs: check unsupported filters in balance arguments
We don't verify that all the balance filter arguments supplemented by
the flags are actually known to the kernel. Thus we let it silently pass
and do nothing.

At the moment this means only the 'limit' filter, but we're going to add
a few more soon so it's better to have that fixed. Also in older stable
kernels so that it works with newer userspace tools.

Cc: stable@vger.kernel.org # 3.16+
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-10-13 18:53:03 -07:00
Chris Mason 62fb50ab7c Merge branch 'anand/sysfs-updates-v4.3-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux into for-linus-4.4
Signed-off-by: Chris Mason <clm@fb.com>
2015-10-12 16:24:15 -07:00
David Sterba f14d104dbd btrfs: switch more printks to our helpers
Convert the simple cases, not all functions provide a way to reach the
fs_info. Also skipped debugging messages (print-tree, integrity
checker and pr_debug) and messages that are printed from possibly
unfinished mount.

Signed-off-by: David Sterba <dsterba@suse.com>
2015-10-08 13:08:03 +02:00
David Sterba ecaeb14b91 btrfs: switch message printers to _in_rcu variants
Signed-off-by: David Sterba <dsterba@suse.com>
2015-10-08 11:07:55 +02:00
Anand Jain a4553fefb5 Btrfs: consolidate btrfs_error() to btrfs_std_error()
btrfs_error() and btrfs_std_error() does the same thing
and calls _btrfs_std_error(), so consolidate them together.
And the main motivation is that btrfs_error() is closely
named with btrfs_err(), one handles error action the other
is to log the error, so don't closely name them.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Suggested-by: David Sterba <dsterba@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2015-09-29 16:30:00 +02:00
Mark Fasheh 293a8489f3 btrfs: fix clone / extent-same deadlocks
Clone and extent same lock their source and target inodes in opposite order.
In addition to this, the range locking in clone doesn't take ordering into
account. Fix this by having clone use the same locking helpers as
btrfs-extent-same.

In addition, I do a small cleanup of the locking helpers, removing a case
(both inodes being the same) which was poorly accounted for and never
actually used by the callers.

Signed-off-by: Mark Fasheh <mfasheh@suse.de>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2015-08-09 07:34:25 -07:00
Liu Bo 4a3560c4f3 Btrfs: fix defrag to merge tail file extent
The file layout is

[extent 1]...[extent n][4k extent][HOLE][extent x]

extent 1~n and 4k extent can be merged during defrag, and the whole
defrag bytes is larger than our defrag thresh(256k), 4k extent as a
tail is left unmerged since we check if its next extent can be merged
(the next one is a hole, so the check will fail), the layout thus can
be

[new extent][4k extent][HOLE][extent x]
 (1~n)

To fix it, beside looking at the next one, this also looks at the
previous one by checking @defrag_end, which is set to 0 when we
decide to stop merging contiguous extents, otherwise, we can merge
the previous one with our extent.

Also, this makes btrfs behave consistent with how xfs and ext4 do.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-08-09 07:33:50 -07:00
Naohiro Aota dd81d459a3 btrfs: fix search key advancing condition
The search key advancing condition used in copy_to_sk() is loose. It can
advance the key even if it reaches sk->max_*: e.g. when the max key = (512,
1024, -1) and the current key = (512, 1025, 10), it increments the
offset by 1, continues hopeless search from (512, 1025, 11). This issue
make ioctl() to take unexpectedly long time scanning all the leaf a blocks
one by one.

This commit fix the problem using standard way of key comparison:
btrfs_comp_cpu_keys()

Signed-off-by: Naohiro Aota <naota@elisp.net>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-08-09 06:17:02 -07:00
Filipe Manana ed95876264 Btrfs: fix file corruption after cloning inline extents
Using the clone ioctl (or extent_same ioctl, which calls the same extent
cloning function as well) we end up allowing copy an inline extent from
the source file into a non-zero offset of the destination file. This is
something not expected and that the btrfs code is not prepared to deal
with - all inline extents must be at a file offset equals to 0.

For example, the following excerpt of a test case for fstests triggers
a crash/BUG_ON() on a write operation after an inline extent is cloned
into a non-zero offset:

  _scratch_mkfs >>$seqres.full 2>&1
  _scratch_mount

  # Create our test files. File foo has the same 2K of data at offset 4K
  # as file bar has at its offset 0.
  $XFS_IO_PROG -f -s -c "pwrite -S 0xaa 0 4K" \
      -c "pwrite -S 0xbb 4k 2K" \
      -c "pwrite -S 0xcc 8K 4K" \
      $SCRATCH_MNT/foo | _filter_xfs_io

  # File bar consists of a single inline extent (2K size).
  $XFS_IO_PROG -f -s -c "pwrite -S 0xbb 0 2K" \
     $SCRATCH_MNT/bar | _filter_xfs_io

  # Now call the clone ioctl to clone the extent of file bar into file
  # foo at its offset 4K. This made file foo have an inline extent at
  # offset 4K, something which the btrfs code can not deal with in future
  # IO operations because all inline extents are supposed to start at an
  # offset of 0, resulting in all sorts of chaos.
  # So here we validate that clone ioctl returns an EOPNOTSUPP, which is
  # what it returns for other cases dealing with inlined extents.
  $CLONER_PROG -s 0 -d $((4 * 1024)) -l $((2 * 1024)) \
      $SCRATCH_MNT/bar $SCRATCH_MNT/foo

  # Because of the inline extent at offset 4K, the following write made
  # the kernel crash with a BUG_ON().
  $XFS_IO_PROG -c "pwrite -S 0xdd 6K 2K" $SCRATCH_MNT/foo | _filter_xfs_io

  status=0
  exit

The stack trace of the BUG_ON() triggered by the last write is:

  [152154.035903] ------------[ cut here ]------------
  [152154.036424] kernel BUG at mm/page-writeback.c:2286!
  [152154.036424] invalid opcode: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
  [152154.036424] Modules linked in: btrfs dm_flakey dm_mod crc32c_generic xor raid6_pq nfsd auth_rpcgss oid_registry nfs_acl nfs lockd grace fscache sunrpc loop fuse parport_pc acpi_cpu$
  [152154.036424] CPU: 2 PID: 17873 Comm: xfs_io Tainted: G        W       4.1.0-rc6-btrfs-next-11+ #2
  [152154.036424] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.8.1-0-g4adadbd-20150316_085822-nilsson.home.kraxel.org 04/01/2014
  [152154.036424] task: ffff880429f70990 ti: ffff880429efc000 task.ti: ffff880429efc000
  [152154.036424] RIP: 0010:[<ffffffff8111a9d5>]  [<ffffffff8111a9d5>] clear_page_dirty_for_io+0x1e/0x90
  [152154.036424] RSP: 0018:ffff880429effc68  EFLAGS: 00010246
  [152154.036424] RAX: 0200000000000806 RBX: ffffea0006a6d8f0 RCX: 0000000000000001
  [152154.036424] RDX: 0000000000000000 RSI: ffffffff81155d1b RDI: ffffea0006a6d8f0
  [152154.036424] RBP: ffff880429effc78 R08: ffff8801ce389fe0 R09: 0000000000000001
  [152154.036424] R10: 0000000000002000 R11: ffffffffffffffff R12: ffff8800200dce68
  [152154.036424] R13: 0000000000000000 R14: ffff8800200dcc88 R15: ffff8803d5736d80
  [152154.036424] FS:  00007fbf119f6700(0000) GS:ffff88043d280000(0000) knlGS:0000000000000000
  [152154.036424] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  [152154.036424] CR2: 0000000001bdc000 CR3: 00000003aa555000 CR4: 00000000000006e0
  [152154.036424] Stack:
  [152154.036424]  ffff8803d5736d80 0000000000000001 ffff880429effcd8 ffffffffa04e97c1
  [152154.036424]  ffff880429effd68 ffff880429effd60 0000000000000001 ffff8800200dc9c8
  [152154.036424]  0000000000000001 ffff8800200dcc88 0000000000000000 0000000000001000
  [152154.036424] Call Trace:
  [152154.036424]  [<ffffffffa04e97c1>] lock_and_cleanup_extent_if_need+0x147/0x18d [btrfs]
  [152154.036424]  [<ffffffffa04ea82c>] __btrfs_buffered_write+0x245/0x4c8 [btrfs]
  [152154.036424]  [<ffffffffa04ed14b>] ? btrfs_file_write_iter+0x150/0x3e0 [btrfs]
  [152154.036424]  [<ffffffffa04ed15a>] ? btrfs_file_write_iter+0x15f/0x3e0 [btrfs]
  [152154.036424]  [<ffffffffa04ed2c7>] btrfs_file_write_iter+0x2cc/0x3e0 [btrfs]
  [152154.036424]  [<ffffffff81165a4a>] __vfs_write+0x7c/0xa5
  [152154.036424]  [<ffffffff81165f89>] vfs_write+0xa0/0xe4
  [152154.036424]  [<ffffffff81166855>] SyS_pwrite64+0x64/0x82
  [152154.036424]  [<ffffffff81465197>] system_call_fastpath+0x12/0x6f
  [152154.036424] Code: 48 89 c7 e8 0f ff ff ff 5b 41 5c 5d c3 0f 1f 44 00 00 55 48 89 e5 41 54 53 48 89 fb e8 ae ef 00 00 49 89 c4 48 8b 03 a8 01 75 02 <0f> 0b 4d 85 e4 74 59 49 8b 3c 2$
  [152154.036424] RIP  [<ffffffff8111a9d5>] clear_page_dirty_for_io+0x1e/0x90
  [152154.036424]  RSP <ffff880429effc68>
  [152154.242621] ---[ end trace e3d3376b23a57041 ]---

Fix this by returning the error EOPNOTSUPP if an attempt to copy an
inline extent into a non-zero offset happens, just like what is done for
other scenarios that would require copying/splitting inline extents,
which were introduced by the following commits:

   00fdf13a2e ("Btrfs: fix a crash of clone with inline extents's split")
   3f9e3df8da ("btrfs: replace error code from btrfs_drop_extents")

Cc: stable@vger.kernel.org
Signed-off-by: Filipe Manana <fdmanana@suse.com>
2015-07-14 16:09:39 +01:00
Filipe Manana 497b4050e0 Btrfs: fix memory leak in the extent_same ioctl
We were allocating memory with memdup_user() but we were never releasing
that memory. This affected pretty much every call to the ioctl, whether
it deduplicated extents or not.

This issue was reported on IRC by Julian Taylor and on the mailing list
by Marcel Ritter, credit goes to them for finding the issue.

Reported-by: Julian Taylor <jtaylor.debian@googlemail.com>
Reported-by: Marcel Ritter <ritter.marcel@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Mark Fasheh <mfasheh@suse.de>
2015-07-11 22:34:26 +01:00
Mark Fasheh 1c919a5e13 btrfs: don't update mtime/ctime on deduped inodes
One issue users have reported is that dedupe changes mtime on files,
resulting in tools like rsync thinking that their contents have changed when
in fact the data is exactly the same. We also skip the ctime update as no
user-visible metadata changes here and we want dedupe to be transparent to
the user.

Clone still wants time changes, so we special case this in the code.

This was tested with the btrfs-extent-same tool.

Signed-off-by: Mark Fasheh <mfasheh@suse.de>
Signed-off-by: Chris Mason <clm@fb.com>
2015-07-01 17:17:17 -07:00
Mark Fasheh 0efa9f48c7 btrfs: allow dedupe of same inode
clone() supports cloning within an inode so extent-same can do
the same now. This patch fixes up the locking in extent-same to
know about the single-inode case. In addition to that, we add a
check for overlapping ranges, which clone does not allow.

Signed-off-by: Mark Fasheh <mfasheh@suse.de>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2015-07-01 17:17:15 -07:00
Mark Fasheh f441460202 btrfs: fix deadlock with extent-same and readpage
->readpage() does page_lock() before extent_lock(), we do the opposite in
extent-same. We want to reverse the order in btrfs_extent_same() but it's
not quite straightforward since the page locks are taken inside btrfs_cmp_data().

So I split btrfs_cmp_data() into 3 parts with a small context structure that
is passed between them. The first, btrfs_cmp_data_prepare() gathers up the
pages needed (taking page lock as required) and puts them on our context
structure. At this point, we are safe to lock the extent range. Afterwards,
we use btrfs_cmp_data() to do the data compare as usual and btrfs_cmp_data_free()
to clean up our context.

Signed-off-by: Mark Fasheh <mfasheh@suse.de>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2015-07-01 17:17:14 -07:00
Mark Fasheh 207910ddee btrfs: pass unaligned length to btrfs_cmp_data()
In the case that we dedupe the tail of a file, we might expand the dedupe
len out to the end of our last block. We don't want to compare data past
i_size however, so pass the original length to btrfs_cmp_data().

Signed-off-by: Mark Fasheh <mfasheh@suse.de>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2015-07-01 17:17:13 -07:00
Mark Fasheh e1d227a42e btrfs: Handle unaligned length in extent_same
The extent-same code rejects requests with an unaligned length. This
poses a problem when we want to dedupe the tail extent of files as we
skip cloning the portion between i_size and the extent boundary.

If we don't clone the entire extent, it won't be deleted. So the
combination of these behaviors winds up giving us worst-case dedupe on
many files.

We can fix this by allowing a length that extents to i_size and
internally aligining those to the end of the block. This is what
btrfs_ioctl_clone() so we can just copy that check over.

Signed-off-by: Mark Fasheh <mfasheh@suse.de>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-10 07:02:50 -07:00
chandan 070034bdf9 Btrfs: btrfs_defrag_file: Fix calculation of max_to_defrag.
max_to_defrag represents the number of pages to defrag rather than the last
page of the file range to be defragged.

Consider a file having 10 4k blocks (i.e. blocks in the range [0 - 9]). If the
defrag ioctl was invoked for the block range [3 - 6], then max_to_defrag
should actually have the value 4. Instead in the current code we end up
setting it to 6.

Now, this does not (yet) cause an issue since the first part of the while loop
condition in btrfs_defrag_file() (i.e. "i <= last_index") causes the control
to flow out of the while loop before any buggy behavior is actually caused. So
the patch just makes sure that max_to_defrag ends up having the right value
rather than fixing a bug. I did run the xfstests suite to make sure that the
code does not regress.

Changelog: v1->v2:
Provide a much descriptive commit message.

Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-10 07:02:48 -07:00
chandan e4826a5b24 Btrfs: btrfs_defrag_file: Fix ra_index computation.
Read-ahead is done for the pages in the range [ra_index, ra_index + cluster -
1]. So the next read-ahead should be starting from the page at index 'ra_index
+ cluster' (unless we deemed that the extent at 'ra_index + cluster' as
non-defraggable) rather than from the page at index 'ra_index +
max_cluster'. This patch fixes this. I did run the xfstests suite to make sure
that the code does not regress.

Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-10 07:02:47 -07:00
David Sterba 01b810b889 btrfs: make root id query unprivileged
The INO_LOOKUP ioctl can lookup path for a given inode number and is
thus restricted. As a sideefect it can find the root id of the
containing subvolume and we're using this int the 'btrfs inspect rootid'
command.

The restriction is unnecessary in case we set the ioctl args
 args::treeid    = 0
 args::objectid  = 256 (BTRFS_FIRST_FREE_OBJECTID)

Then the path will be empty and the treeid is filled with the root id of
the inode on which the ioctl is called. This behaviour is unchanged,
after the root restriction is removed.

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-02 19:34:36 -07:00
David Sterba 6d13f5497f btrfs: fix warnings after changes in btrfs_abort_transaction
fs/btrfs/volumes.c: In function ‘btrfs_create_uuid_tree’:
fs/btrfs/volumes.c:3909:3: warning: format ‘%d’ expects argument of type ‘int’, but argument 4 has type ‘long int’ [-Wformat=]
   btrfs_abort_transaction(trans, tree_root,
   ^
  CC [M]  fs/btrfs/ioctl.o
fs/btrfs/ioctl.c: In function ‘create_subvol’:
fs/btrfs/ioctl.c:549:3: warning: format ‘%d’ expects argument of type ‘int’, but argument 4 has type ‘long int’ [-Wformat=]
   btrfs_abort_transaction(trans, root, PTR_ERR(new_root));

PTR_ERR returns long, but we're really using 'int' for the error codes
everywhere so just set and use the local variable.

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-02 19:34:34 -07:00
Omar Sandoval 64ad6c4889 Btrfs: don't invalidate root dentry when subvolume deletion fails
Since commit bafc9b754f ("vfs: More precise tests in d_invalidate"),
mounted subvolumes can be deleted because d_invalidate() won't fail.
However, we run into problems when we attempt to delete the default
subvolume while it is mounted as the root filesystem:

	# btrfs subvol list /
	ID 257 gen 306 top level 5 path rootvol
	ID 267 gen 334 top level 5 path snap1
	# btrfs subvol get-default /
	ID 267 gen 334 top level 5 path snap1
	# btrfs inspect-internal rootid /
	267
	# mount -o subvol=/ /dev/vda1 /mnt
	# btrfs subvol del /mnt/snap1
	Delete subvolume (no-commit): '/mnt/snap1'
	ERROR: cannot delete '/mnt/snap1' - Operation not permitted
	# findmnt /
	findmnt: can't read /proc/mounts: No such file or directory
	# ls /proc
	#

Markus reported that this same scenario simply led to a kernel oops.

This happens because in btrfs_ioctl_snap_destroy(), we call
d_invalidate() before we check may_destroy_subvol(), which means that we
detach the submounts and drop the dentry before erroring out. Instead,
we should only invalidate the dentry once the deletion has succeeded.
Additionally, the shrink_dcache_sb() isn't necessary; d_invalidate()
will prune the dcache for the deleted subvolume.

Cc: <stable@vger.kernel.org>
Fixes: bafc9b754f ("vfs: More precise tests in d_invalidate")
Reported-by: Markus Schauler <mschauler@gmail.com>
Signed-off-by: Omar Sandoval <osandov@osandov.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-02 19:34:33 -07:00
Linus Torvalds 64887b6882 Merge branch 'for-linus-4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs fixes from Chris Mason:
 "A few more btrfs fixes.

  These range from corners Filipe found in the new free space cache
  writeback to a grab bag of fixes from the list"

* 'for-linus-4.1' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  Btrfs: btrfs_release_extent_buffer_page didn't free pages of dummy extent
  Btrfs: fill ->last_trans for delayed inode in btrfs_fill_inode.
  btrfs: unlock i_mutex after attempting to delete subvolume during send
  btrfs: check io_ctl_prepare_pages return in __btrfs_write_out_cache
  btrfs: fix race on ENOMEM in alloc_extent_buffer
  btrfs: handle ENOMEM in btrfs_alloc_tree_block
  Btrfs: fix find_free_dev_extent() malfunction in case device tree has hole
  Btrfs: don't check for delalloc_bytes in cache_save_setup
  Btrfs: fix deadlock when starting writeback of bg caches
  Btrfs: fix race between start dirty bg cache writeout and bg deletion
2015-05-01 07:46:21 -07:00
Linus Torvalds 9ec3a646fe Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull fourth vfs update from Al Viro:
 "d_inode() annotations from David Howells (sat in for-next since before
  the beginning of merge window) + four assorted fixes"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  RCU pathwalk breakage when running into a symlink overmounting something
  fix I_DIO_WAKEUP definition
  direct-io: only inc/dec inode->i_dio_count for file systems
  fs/9p: fix readdir()
  VFS: assorted d_backing_inode() annotations
  VFS: fs/inode.c helpers: d_inode() annotations
  VFS: fs/cachefiles: d_backing_inode() annotations
  VFS: fs library helpers: d_inode() annotations
  VFS: assorted weird filesystems: d_inode() annotations
  VFS: normal filesystems (and lustre): d_inode() annotations
  VFS: security/: d_inode() annotations
  VFS: security/: d_backing_inode() annotations
  VFS: net/: d_inode() annotations
  VFS: net/unix: d_backing_inode() annotations
  VFS: kernel/: d_inode() annotations
  VFS: audit: d_backing_inode() annotations
  VFS: Fix up some ->d_inode accesses in the chelsio driver
  VFS: Cachefiles should perform fs modifications on the top layer only
  VFS: AF_UNIX sockets should call mknod on the top layer only
2015-04-26 17:22:07 -07:00
Omar Sandoval 909e26dce3 btrfs: unlock i_mutex after attempting to delete subvolume during send
Whenever the check for a send in progress introduced in commit
521e0546c9 (btrfs: protect snapshots from deleting during send) is
hit, we return without unlocking inode->i_mutex. This is easy to see
with lockdep enabled:

[  +0.000059] ================================================
[  +0.000028] [ BUG: lock held when returning to user space! ]
[  +0.000029] 4.0.0-rc5-00096-g3c435c1 #93 Not tainted
[  +0.000026] ------------------------------------------------
[  +0.000029] btrfs/211 is leaving the kernel with locks still held!
[  +0.000029] 1 lock held by btrfs/211:
[  +0.000023]  #0:  (&type->i_mutex_dir_key){+.+.+.}, at: [<ffffffff8135b8df>] btrfs_ioctl_snap_destroy+0x2df/0x7a0

Make sure we unlock it in the error path.

Reviewed-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Cc: stable@vger.kernel.org
Signed-off-by: Omar Sandoval <osandov@osandov.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-04-26 06:27:02 -07:00
David Howells 2b0143b5c9 VFS: normal filesystems (and lustre): d_inode() annotations
that's the bulk of filesystem drivers dealing with inodes of their own

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-15 15:06:57 -04:00
Qu Wenruo e082f56313 btrfs: quota: Update quota tree after qgroup relationship change.
Previous patch modified the in memory struct but it's not written in
quota tree until next commit.
So user will still get old data using "btrfs qgroup show" after
assign/remove.

This patch will call btrfs_run_qgroups in assign ioctl so it will be
updated to in memory quota trees and user will get up-to-date results.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-04-13 07:53:00 -07:00
Qu Wenruo e09fe2d211 btrfs: Don't allow subvolid >= (1 << BTRFS_QGROUP_LEVEL_SHIFT) to be created
Btrfs will create qgroup on subvolume creation if quota is enabled, but
qgroup uses the high bits(currently 16 bits) as level, to build the
inheritance.

However it is fully possible a subvolume can be created with a
subvolumeid larger than 1 << BTRFS_QGROUP_LEVEL_SHIFT, so it will be
considered as level 1 and can't be assigned to other qgroup in level 1.

This patch will prevent such things so qgroup inheritance will not be
screwed up.
The downside is very clear, btrfs subvolume number limit will decrease
from (u64 max - 256(fisrt free objectid) - 256(last free objectid)) to
(u48 max -256(first free objectid)).
But we still have near u48(that's 15 digits in dec), so that should not
be a huge problem.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-04-13 07:52:54 -07:00
Dongsheng Yang 4087cf24ae Btrfs: qgroup: cleanup, remove an unsued parameter in btrfs_create_qgroup().
Signed-off-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-04-13 07:52:44 -07:00
Chris Mason de249e66a7 Btrfs: fix uninit variable in clone ioctl
Commit 0d97a64e0 creates a new variable but doesn't always set it up.
This puts it back to the original method (key.offset + 1) for the cases
not covered by Filipe's new logic.

Signed-off-by: Chris Mason <clm@fb.com>
2015-04-13 07:03:58 -07:00
Filipe Manana ccccf3d672 Btrfs: fix inode eviction infinite loop after cloning into it
If we attempt to clone a 0 length region into a file we can end up
inserting a range in the inode's extent_io tree with a start offset
that is greater then the end offset, which triggers immediately the
following warning:

[ 3914.619057] WARNING: CPU: 17 PID: 4199 at fs/btrfs/extent_io.c:435 insert_state+0x4b/0x10b [btrfs]()
[ 3914.620886] BTRFS: end < start 4095 4096
(...)
[ 3914.638093] Call Trace:
[ 3914.638636]  [<ffffffff81425fd9>] dump_stack+0x4c/0x65
[ 3914.639620]  [<ffffffff81045390>] warn_slowpath_common+0xa1/0xbb
[ 3914.640789]  [<ffffffffa03ca44f>] ? insert_state+0x4b/0x10b [btrfs]
[ 3914.642041]  [<ffffffff810453f0>] warn_slowpath_fmt+0x46/0x48
[ 3914.643236]  [<ffffffffa03ca44f>] insert_state+0x4b/0x10b [btrfs]
[ 3914.644441]  [<ffffffffa03ca729>] __set_extent_bit+0x107/0x3f4 [btrfs]
[ 3914.645711]  [<ffffffffa03cb256>] lock_extent_bits+0x65/0x1bf [btrfs]
[ 3914.646914]  [<ffffffff8142b2fb>] ? _raw_spin_unlock+0x28/0x33
[ 3914.648058]  [<ffffffffa03cbac4>] ? test_range_bit+0xcc/0xde [btrfs]
[ 3914.650105]  [<ffffffffa03cb3c3>] lock_extent+0x13/0x15 [btrfs]
[ 3914.651361]  [<ffffffffa03db39e>] lock_extent_range+0x3d/0xcd [btrfs]
[ 3914.652761]  [<ffffffffa03de1fe>] btrfs_ioctl_clone+0x278/0x388 [btrfs]
[ 3914.654128]  [<ffffffff811226dd>] ? might_fault+0x58/0xb5
[ 3914.655320]  [<ffffffffa03e0909>] btrfs_ioctl+0xb51/0x2195 [btrfs]
(...)
[ 3914.669271] ---[ end trace 14843d3e2e622fc1 ]---

This later makes the inode eviction handler enter an infinite loop that
keeps dumping the following warning over and over:

[ 3915.117629] WARNING: CPU: 22 PID: 4228 at fs/btrfs/extent_io.c:435 insert_state+0x4b/0x10b [btrfs]()
[ 3915.119913] BTRFS: end < start 4095 4096
(...)
[ 3915.137394] Call Trace:
[ 3915.137913]  [<ffffffff81425fd9>] dump_stack+0x4c/0x65
[ 3915.139154]  [<ffffffff81045390>] warn_slowpath_common+0xa1/0xbb
[ 3915.140316]  [<ffffffffa03ca44f>] ? insert_state+0x4b/0x10b [btrfs]
[ 3915.141505]  [<ffffffff810453f0>] warn_slowpath_fmt+0x46/0x48
[ 3915.142709]  [<ffffffffa03ca44f>] insert_state+0x4b/0x10b [btrfs]
[ 3915.143849]  [<ffffffffa03ca729>] __set_extent_bit+0x107/0x3f4 [btrfs]
[ 3915.145120]  [<ffffffffa038c1e3>] ? btrfs_kill_super+0x17/0x23 [btrfs]
[ 3915.146352]  [<ffffffff811548f6>] ? deactivate_locked_super+0x3b/0x50
[ 3915.147565]  [<ffffffffa03cb256>] lock_extent_bits+0x65/0x1bf [btrfs]
[ 3915.148785]  [<ffffffff8142b7e2>] ? _raw_write_unlock+0x28/0x33
[ 3915.149931]  [<ffffffffa03bc325>] btrfs_evict_inode+0x196/0x482 [btrfs]
[ 3915.151154]  [<ffffffff81168904>] evict+0xa0/0x148
[ 3915.152094]  [<ffffffff811689e5>] dispose_list+0x39/0x43
[ 3915.153081]  [<ffffffff81169564>] evict_inodes+0xdc/0xeb
[ 3915.154062]  [<ffffffff81154418>] generic_shutdown_super+0x49/0xef
[ 3915.155193]  [<ffffffff811546d1>] kill_anon_super+0x13/0x1e
[ 3915.156274]  [<ffffffffa038c1e3>] btrfs_kill_super+0x17/0x23 [btrfs]
(...)
[ 3915.167404] ---[ end trace 14843d3e2e622fc2 ]---

So just bail out of the clone ioctl if the length of the region to clone
is zero, without locking any extent range, in order to prevent this issue
(same behaviour as a pwrite with a 0 length for example).

This is trivial to reproduce. For example, the steps for the test I just
made for fstests:

  mkfs.btrfs -f SCRATCH_DEV
  mount SCRATCH_DEV $SCRATCH_MNT

  touch $SCRATCH_MNT/foo
  touch $SCRATCH_MNT/bar

  $CLONER_PROG -s 0 -d 4096 -l 0 $SCRATCH_MNT/foo $SCRATCH_MNT/bar
  umount $SCRATCH_MNT

A test case for fstests follows soon.

CC: <stable@vger.kernel.org>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Omar Sandoval <osandov@osandov.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-04-13 07:03:28 -07:00
Filipe Manana 113e828386 Btrfs: fix inode eviction infinite loop after extent_same ioctl
If we pass a length of 0 to the extent_same ioctl, we end up locking an
extent range with a start offset greater then its end offset (if the
destination file's offset is greater than zero). This results in a warning
from extent_io.c:insert_state through the following call chain:

  btrfs_extent_same()
    btrfs_double_lock()
      lock_extent_range()
        lock_extent(inode->io_tree, offset, offset + len - 1)
          lock_extent_bits()
            __set_extent_bit()
              insert_state()
                --> WARN_ON(end < start)

This leads to an infinite loop when evicting the inode. This is the same
problem that my previous patch titled
"Btrfs: fix inode eviction infinite loop after cloning into it" addressed
but for the extent_same ioctl instead of the clone ioctl.

CC: <stable@vger.kernel.org>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Omar Sandoval <osandov@osandov.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-04-13 07:03:27 -07:00
Filipe Manana df858e7672 Btrfs: fix range cloning when same inode used as source and destination
While searching for extents to clone we might find one where we only use
a part of it coming from its tail. If our destination inode is the same
the source inode, we end up removing the tail part of the extent item and
insert after a new one that point to the same extent with an adjusted
key file offset and data offset. After this we search for the next extent
item in the fs/subvol tree with a key that has an offset incremented by
one. But this second search leaves us at the new extent item we inserted
previously, and since that extent item has a non-zero data offset, it
it can make us call btrfs_drop_extents with an empty range (start == end)
which causes the following warning:

[23978.537119] WARNING: CPU: 6 PID: 16251 at fs/btrfs/file.c:550 btrfs_drop_extent_cache+0x43/0x385 [btrfs]()
(...)
[23978.557266] Call Trace:
[23978.557978]  [<ffffffff81425fd9>] dump_stack+0x4c/0x65
[23978.559191]  [<ffffffff81045390>] warn_slowpath_common+0xa1/0xbb
[23978.560699]  [<ffffffffa047f0ea>] ? btrfs_drop_extent_cache+0x43/0x385 [btrfs]
[23978.562389]  [<ffffffff8104544d>] warn_slowpath_null+0x1a/0x1c
[23978.563613]  [<ffffffffa047f0ea>] btrfs_drop_extent_cache+0x43/0x385 [btrfs]
[23978.565103]  [<ffffffff810e3a18>] ? time_hardirqs_off+0x15/0x28
[23978.566294]  [<ffffffff81079ff8>] ? trace_hardirqs_off+0xd/0xf
[23978.567438]  [<ffffffffa047f73d>] __btrfs_drop_extents+0x6b/0x9e1 [btrfs]
[23978.568702]  [<ffffffff8107c03f>] ? trace_hardirqs_on+0xd/0xf
[23978.569763]  [<ffffffff811441c0>] ? ____cache_alloc+0x69/0x2eb
[23978.570817]  [<ffffffff81142269>] ? virt_to_head_page+0x9/0x36
[23978.571872]  [<ffffffff81143c15>] ? cache_alloc_debugcheck_after.isra.42+0x16c/0x1cb
[23978.573466]  [<ffffffff811420d5>] ? kmemleak_alloc_recursive.constprop.52+0x16/0x18
[23978.574962]  [<ffffffffa0480d07>] btrfs_drop_extents+0x66/0x7f [btrfs]
[23978.576179]  [<ffffffffa049aa35>] btrfs_clone+0x516/0xaf5 [btrfs]
[23978.577311]  [<ffffffffa04983dc>] ? lock_extent_range+0x7b/0xcd [btrfs]
[23978.578520]  [<ffffffffa049b2a2>] btrfs_ioctl_clone+0x28e/0x39f [btrfs]
[23978.580282]  [<ffffffffa049d9ae>] btrfs_ioctl+0xb51/0x219a [btrfs]
(...)
[23978.591887] ---[ end trace 988ec2a653d03ed3 ]---

Then we attempt to insert a new extent item with a key that already
exists, which makes btrfs_insert_empty_item return -EEXIST resulting in
abortion of the current transaction:

[23978.594355] WARNING: CPU: 6 PID: 16251 at fs/btrfs/super.c:260 __btrfs_abort_transaction+0x52/0x114 [btrfs]()
(...)
[23978.622589] Call Trace:
[23978.623181]  [<ffffffff81425fd9>] dump_stack+0x4c/0x65
[23978.624359]  [<ffffffff81045390>] warn_slowpath_common+0xa1/0xbb
[23978.625573]  [<ffffffffa044ab6c>] ? __btrfs_abort_transaction+0x52/0x114 [btrfs]
[23978.626971]  [<ffffffff810453f0>] warn_slowpath_fmt+0x46/0x48
[23978.628003]  [<ffffffff8108a6c8>] ? vprintk_default+0x1d/0x1f
[23978.629138]  [<ffffffffa044ab6c>] __btrfs_abort_transaction+0x52/0x114 [btrfs]
[23978.630528]  [<ffffffffa049ad1b>] btrfs_clone+0x7fc/0xaf5 [btrfs]
[23978.631635]  [<ffffffffa04983dc>] ? lock_extent_range+0x7b/0xcd [btrfs]
[23978.632886]  [<ffffffffa049b2a2>] btrfs_ioctl_clone+0x28e/0x39f [btrfs]
[23978.634119]  [<ffffffffa049d9ae>] btrfs_ioctl+0xb51/0x219a [btrfs]
(...)
[23978.647714] ---[ end trace 988ec2a653d03ed4 ]---

This is wrong because we should not process the extent item that we just
inserted previously, and instead process the extent item that follows it
in the tree

For example for the test case I wrote for fstests:

   bs=$((64 * 1024))
   mkfs.btrfs -f -l $bs -O ^no-holes /dev/sdc
   mount /dev/sdc /mnt

   xfs_io -f -c "pwrite -S 0xaa $(($bs * 2)) $(($bs * 2))" /mnt/foo

   $CLONER_PROG -s $((3 * $bs)) -d $((267 * $bs)) -l 0 /mnt/foo /mnt/foo
   $CLONER_PROG -s $((217 * $bs)) -d $((95 * $bs)) -l 0 /mnt/foo /mnt/foo

The second clone call fails with -EEXIST, because when we process the
first extent item (offset 262144), we drop part of it (counting from the
end) and then insert a new extent item with a key greater then the key we
found. The next time we search the tree we search for a key with offset
262144 + 1, which leaves us at the new extent item we have just inserted
but we think it refers to an extent that we need to clone.

Fix this by ensuring the next search key uses an offset corresponding to
the offset of the key we found previously plus the data length of the
corresponding extent item. This ensures we skip new extent items that we
inserted and works for the case of implicit holes too (NO_HOLES feature).

A test case for fstests follows soon.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-04-13 07:03:26 -07:00
Chris Mason 9deed229fa Merge branch 'cleanups-for-4.1-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux into for-linus-4.1 2015-03-25 10:43:16 -07:00
David Sterba b8b93addde btrfs: cleanup 64bit/32bit divs, provably bounded values
The divisor is derived from nodesize or PAGE_SIZE, fits into 32bit type.
Get rid of a few more do_div instances.

Signed-off-by: David Sterba <dsterba@suse.cz>
2015-03-03 17:24:00 +01:00
David Sterba 3284da7b7b btrfs: use explicit initializer for seq_elem
Using {} as initializer for struct seq_elem does not properly initialize
the list_head member, but it currently works because it gets set through
btrfs_get_tree_mod_seq if 'seq' is 0.

Signed-off-by: David Sterba <dsterba@suse.cz>
2015-03-03 17:23:59 +01:00
David Howells e36cb0b89c VFS: (Scripted) Convert S_ISLNK/DIR/REG(dentry->d_inode) to d_is_*(dentry)
Convert the following where appropriate:

 (1) S_ISLNK(dentry->d_inode) to d_is_symlink(dentry).

 (2) S_ISREG(dentry->d_inode) to d_is_reg(dentry).

 (3) S_ISDIR(dentry->d_inode) to d_is_dir(dentry).  This is actually more
     complicated than it appears as some calls should be converted to
     d_can_lookup() instead.  The difference is whether the directory in
     question is a real dir with a ->lookup op or whether it's a fake dir with
     a ->d_automount op.

In some circumstances, we can subsume checks for dentry->d_inode not being
NULL into this, provided we the code isn't in a filesystem that expects
d_inode to be NULL if the dirent really *is* negative (ie. if we're going to
use d_inode() rather than d_backing_inode() to get the inode pointer).

Note that the dentry type field may be set to something other than
DCACHE_MISS_TYPE when d_inode is NULL in the case of unionmount, where the VFS
manages the fall-through from a negative dentry to a lower layer.  In such a
case, the dentry type of the negative union dentry is set to the same as the
type of the lower dentry.

However, if you know d_inode is not NULL at the call site, then you can use
the d_is_xxx() functions even in a filesystem.

There is one further complication: a 0,0 chardev dentry may be labelled
DCACHE_WHITEOUT_TYPE rather than DCACHE_SPECIAL_TYPE.  Strictly, this was
intended for special directory entry types that don't have attached inodes.

The following perl+coccinelle script was used:

use strict;

my @callers;
open($fd, 'git grep -l \'S_IS[A-Z].*->d_inode\' |') ||
    die "Can't grep for S_ISDIR and co. callers";
@callers = <$fd>;
close($fd);
unless (@callers) {
    print "No matches\n";
    exit(0);
}

my @cocci = (
    '@@',
    'expression E;',
    '@@',
    '',
    '- S_ISLNK(E->d_inode->i_mode)',
    '+ d_is_symlink(E)',
    '',
    '@@',
    'expression E;',
    '@@',
    '',
    '- S_ISDIR(E->d_inode->i_mode)',
    '+ d_is_dir(E)',
    '',
    '@@',
    'expression E;',
    '@@',
    '',
    '- S_ISREG(E->d_inode->i_mode)',
    '+ d_is_reg(E)' );

my $coccifile = "tmp.sp.cocci";
open($fd, ">$coccifile") || die $coccifile;
print($fd "$_\n") || die $coccifile foreach (@cocci);
close($fd);

foreach my $file (@callers) {
    chomp $file;
    print "Processing ", $file, "\n";
    system("spatch", "--sp-file", $coccifile, $file, "--in-place", "--no-show-diff") == 0 ||
	die "spatch failed";
}

[AV: overlayfs parts skipped]

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-02-22 11:38:41 -05:00
Linus Torvalds bdeb03cada Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs update from Chris Mason:
 "From a feature point of view, most of the code here comes from Miao
  Xie and others at Fujitsu to implement scrubbing and replacing devices
  on raid56.  This has been in development for a while, and it's a big
  improvement.

  Filipe and Josef have a great assortment of fixes, many of which solve
  problems corruptions either after a crash or in error conditions.  I
  still have a round two from Filipe for next week that solves
  corruptions with discard and block group removal"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (62 commits)
  Btrfs: make get_caching_control unconditionally return the ctl
  Btrfs: fix unprotected deletion from pending_chunks list
  Btrfs: fix fs mapping extent map leak
  Btrfs: fix memory leak after block remove + trimming
  Btrfs: make btrfs_abort_transaction consider existence of new block groups
  Btrfs: fix race between writing free space cache and trimming
  Btrfs: fix race between fs trimming and block group remove/allocation
  Btrfs, replace: enable dev-replace for raid56
  Btrfs: fix freeing used extents after removing empty block group
  Btrfs: fix crash caused by block group removal
  Btrfs: fix invalid block group rbtree access after bg is removed
  Btrfs, raid56: fix use-after-free problem in the final device replace procedure on raid56
  Btrfs, replace: write raid56 parity into the replace target device
  Btrfs, replace: write dirty pages into the replace target device
  Btrfs, raid56: support parity scrub on raid56
  Btrfs, raid56: use a variant to record the operation type
  Btrfs, scrub: repair the common data on RAID5/6 if it is corrupted
  Btrfs, raid56: don't change bbio and raid_map
  Btrfs: remove unnecessary code of stripe_index assignment in __btrfs_map_block
  Btrfs: remove noused bbio_ret in __btrfs_map_block in condition
  ...
2014-12-12 11:15:23 -08:00
Filipe Manana 9ea24bbe17 Btrfs: fix snapshot inconsistency after a file write followed by truncate
If right after starting the snapshot creation ioctl we perform a write against a
file followed by a truncate, with both operations increasing the file's size, we
can get a snapshot tree that reflects a state of the source subvolume's tree where
the file truncation happened but the write operation didn't. This leaves a gap
between 2 file extent items of the inode, which makes btrfs' fsck complain about it.

For example, if we perform the following file operations:

    $ mkfs.btrfs -f /dev/vdd
    $ mount /dev/vdd /mnt
    $ xfs_io -f \
          -c "pwrite -S 0xaa -b 32K 0 32K" \
          -c "fsync" \
          -c "pwrite -S 0xbb -b 32770 16K 32770" \
          -c "truncate 90123" \
          /mnt/foobar

and the snapshot creation ioctl was just called before the second write, we often
can get the following inode items in the snapshot's btree:

        item 120 key (257 INODE_ITEM 0) itemoff 7987 itemsize 160
                inode generation 146 transid 7 size 90123 block group 0 mode 100600 links 1 uid 0 gid 0 rdev 0 flags 0x0
        item 121 key (257 INODE_REF 256) itemoff 7967 itemsize 20
                inode ref index 282 namelen 10 name: foobar
        item 122 key (257 EXTENT_DATA 0) itemoff 7914 itemsize 53
                extent data disk byte 1104855040 nr 32768
                extent data offset 0 nr 32768 ram 32768
                extent compression 0
        item 123 key (257 EXTENT_DATA 53248) itemoff 7861 itemsize 53
                extent data disk byte 0 nr 0
                extent data offset 0 nr 40960 ram 40960
                extent compression 0

There's a file range, corresponding to the interval [32K; ALIGN(16K + 32770, 4096)[
for which there's no file extent item covering it. This is because the file write
and file truncate operations happened both right after the snapshot creation ioctl
called btrfs_start_delalloc_inodes(), which means we didn't start and wait for the
ordered extent that matches the write and, in btrfs_setsize(), we were able to call
btrfs_cont_expand() before being able to commit the current transaction in the
snapshot creation ioctl. So this made it possibe to insert the hole file extent
item in the source subvolume (which represents the region added by the truncate)
right before the transaction commit from the snapshot creation ioctl.

Btrfs' fsck tool complains about such cases with a message like the following:

    "root 331 inode 257 errors 100, file extent discount"

>From a user perspective, the expectation when a snapshot is created while those
file operations are being performed is that the snapshot will have a file that
either:

1) is empty
2) only the first write was captured
3) only the 2 writes were captured
4) both writes and the truncation were captured

But never capture a state where only the first write and the truncation were
captured (since the second write was performed before the truncation).

A test case for xfstests follows.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-11-25 07:41:23 -08:00
Filipe Manana e5fa8f865b Btrfs: ensure send always works on roots without orphans
Move the logic from the snapshot creation ioctl into send. This avoids
doing the transaction commit if send isn't used, and ensures that if
a crash/reboot happens after the transaction commit that created the
snapshot and before the transaction commit that switched the commit
root, send will not get a commit root that differs from the main root
(that has orphan items).

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-11-25 07:41:23 -08:00
Al Viro ddb52f4fd2 btrfs: get rid of f_dentry use
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-11-19 13:01:21 -05:00
Miklos Szeredi cbdf35bcb8 vfs: export check_sticky()
It's already duplicated in btrfs and about to be used in overlayfs too.

Move the sticky bit check to an inline helper and call the out-of-line
helper only in the unlikly case of the sticky bit being set.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-10-24 00:14:36 +02:00
Linus Torvalds ef161ea1ff Merge branch 'for-linus-update' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs data corruption fix from Chris Mason:
 "I'm testing a pull with more fixes, but wanted to get this one out so
  Greg can pick it up.

  The corruption isn't easy to hit, you have to do a readonly snapshot
  and have orphans in the snapshot.  But my review and testing missed
  the bug.  Filipe has added a better xfstest to cover it"

* 'for-linus-update' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  Revert "Btrfs: race free update of commit root for ro snapshots"
2014-10-18 13:32:17 -07:00
Chris Mason d37973082b Revert "Btrfs: race free update of commit root for ro snapshots"
This reverts commit 9c3b306e1c.

Switching only one commit root during a transaction is wrong because it
leads the fs into an inconsistent state. All commit roots should be
switched at once, at transaction commit time, otherwise backref walking
can often miss important references that were only accessible through
the old commit root.  Plus, the root item for the snapshot's root wasn't
getting updated and preventing the next transaction commit to do it.

This made several users get into random corruption issues after creation
of readonly snapshots.

A regression test for xfstests will follow soon.

Cc: stable@vger.kernel.org # 3.17
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-10-17 02:40:59 -07:00
Linus Torvalds 77c688ac87 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs updates from Al Viro:
 "The big thing in this pile is Eric's unmount-on-rmdir series; we
  finally have everything we need for that.  The final piece of prereqs
  is delayed mntput() - now filesystem shutdown always happens on
  shallow stack.

  Other than that, we have several new primitives for iov_iter (Matt
  Wilcox, culled from his XIP-related series) pushing the conversion to
  ->read_iter()/ ->write_iter() a bit more, a bunch of fs/dcache.c
  cleanups and fixes (including the external name refcounting, which
  gives consistent behaviour of d_move() wrt procfs symlinks for long
  and short names alike) and assorted cleanups and fixes all over the
  place.

  This is just the first pile; there's a lot of stuff from various
  people that ought to go in this window.  Starting with
  unionmount/overlayfs mess...  ;-/"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (60 commits)
  fs/file_table.c: Update alloc_file() comment
  vfs: Deduplicate code shared by xattr system calls operating on paths
  reiserfs: remove pointless forward declaration of struct nameidata
  don't need that forward declaration of struct nameidata in dcache.h anymore
  take dname_external() into fs/dcache.c
  let path_init() failures treated the same way as subsequent link_path_walk()
  fix misuses of f_count() in ppp and netlink
  ncpfs: use list_for_each_entry() for d_subdirs walk
  vfs: move getname() from callers to do_mount()
  gfs2_atomic_open(): skip lookups on hashed dentry
  [infiniband] remove pointless assignments
  gadgetfs: saner API for gadgetfs_create_file()
  f_fs: saner API for ffs_sb_create_file()
  jfs: don't hash direct inode
  [s390] remove pointless assignment of ->f_op in vmlogrdr ->open()
  ecryptfs: ->f_op is never NULL
  android: ->f_op is never NULL
  nouveau: __iomem misannotations
  missing annotation in fs/file.c
  fs: namespace: suppress 'may be used uninitialized' warnings
  ...
2014-10-13 11:28:42 +02:00
Eric W. Biederman 5542aa2fa7 vfs: Make d_invalidate return void
Now that d_invalidate can no longer fail, stop returning a useless
return code.  For the few callers that checked the return code update
remove the handling of d_invalidate failure.

Reviewed-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-10-09 02:38:57 -04:00
Chris Mason 0ec31a61f0 Merge branch 'remove-unlikely' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux into for-linus 2014-10-04 09:57:44 -07:00
Chris Mason 27b19cc886 Merge branch 'cleanup/blocksize-diet-part1' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux into for-linus 2014-10-04 09:57:14 -07:00
David Sterba 4d75f8a9c8 btrfs: remove blocksize from btrfs_alloc_free_block and rename
Rename to btrfs_alloc_tree_block as it fits to the alloc/find/free +
_tree_block family. The parameter blocksize was set to the metadata
block size, directly or indirectly.

Signed-off-by: David Sterba <dsterba@suse.cz>
2014-10-02 17:14:54 +02:00
David Sterba ee39b432b4 btrfs: remove unlikely from data-dependent branches and slow paths
There are the branch hints that obviously depend on the data being
processed, the CPU predictor will do better job according to the actual
load. It also does not make sense to use the hints in slow paths that do
a lot of other operations like locking, waiting or IO.

Signed-off-by: David Sterba <dsterba@suse.cz>
2014-10-02 16:15:21 +02:00
David Sterba aab110abcb btrfs: defrag, use unsigned type for extent thresh
Signed type mismatches the ioctl structure, all extent calculations are
done on unsigned types.

Signed-off-by: David Sterba <dsterba@suse.cz>
2014-10-01 19:30:52 +02:00
Miao Xie 7cc8e58d53 Btrfs: fix unprotected device's variants on 32bits machine
->total_bytes,->disk_total_bytes,->bytes_used is protected by chunk
lock when we change them, but sometimes we read them without any lock,
and we might get unexpected value. We fix this problem like inode's
i_size.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-09-17 13:38:38 -07:00
Filipe Manana 78a017a2c9 Btrfs: add missing compression property remove in btrfs_ioctl_setflags
The behaviour of a 'chattr -c' consists of getting the current flags,
clearing the FS_COMPR_FL bit and then sending the result to the set
flags ioctl - this means the bit FS_NOCOMP_FL isn't set in the flags
passed to the ioctl. This results in the compression property not being
cleared from the inode - it was cleared only if the bit FS_NOCOMP_FL
was set in the received flags.

Reproducer:

    $ mkfs.btrfs -f /dev/sdd
    $ mount /dev/sdd /mnt && cd /mnt
    $ mkdir a
    $ chattr +c a
    $ touch a/file
    $ lsattr a/file
    --------c------- a/file
    $ chattr -c a
    $ touch a/file2
    $ lsattr a/file2
    --------c------- a/file2
    $ lsattr -d a
    ---------------- a

Reported-by: Andreas Schneider <asn@cryptomilk.org>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-09-17 13:38:23 -07:00
Filipe Manana f98de9b9c0 Btrfs: make btrfs_search_forward return with nodes unlocked
None of the uses of btrfs_search_forward() need to have the path
nodes (level >= 1) read locked, only the leaf needs to be locked
while the caller processes it. Therefore make it return a path
with all nodes unlocked, except for the leaf.

This change is motivated by the observation that during a file
fsync we repeatdly call btrfs_search_forward() and process the
returned leaf while upper nodes of the returned path (level >= 1)
are read locked, which unnecessarily blocks other tasks that want
to write to the same fs/subvol btree.
Therefore instead of modifying the fsync code to unlock all nodes
with level >= 1 immediately after calling btrfs_search_forward(),
change btrfs_search_forward() to do it, so that it benefits all
callers.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-09-17 13:38:02 -07:00
David Sterba 2fad4e83e1 btrfs: wake up transaction thread from SYNC_FS ioctl
The transaction thread may want to do more work, namely it pokes the
cleaner ktread that will start processing uncleaned subvols.

This can be triggered by user via the 'btrfs fi sync' command, otherwise
there was a delay up to 30 seconds before the cleaner started to clean
old snapshots.

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2014-09-17 13:37:42 -07:00
Anand Jain ec95d4917b btrfs: device delete must be sysloged
as in the disk add patch, disk detached from the volume must be
recorded in the syslog as well for the same reason.

Signed-off-by: Anand Jain <Anand.Jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2014-09-17 13:37:23 -07:00
Anand Jain 43d2076168 btrfs: device add must be sysloged
when we add a new disk to the mounted btrfs we don't record it
as of now, disk add is a critical change of btrfs configuration,
it must be recorded in the syslog to help offline investigations
of customer problems when reported.

Signed-off-by: Anand Jain <Anand.Jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2014-09-17 13:37:20 -07:00
David Sterba ed6078f703 btrfs: use DIV_ROUND_UP instead of open-coded variants
The form

  (value + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT

is equivalent to

  (value + PAGE_CACHE_SIZE - 1) / PAGE_CACHE_SIZE

The rest is a simple subsitution, no difference in the generated
assembly code.

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2014-09-17 13:37:17 -07:00
David Sterba 707e8a0715 btrfs: use nodesize everywhere, kill leafsize
The nodesize and leafsize were never of different values. Unify the
usage and make nodesize the one. Cleanup the redundant checks and
helpers.

Shaves a few bytes from .text:

  text    data     bss     dec     hex filename
852418   24560   23112  900090   dbbfa btrfs.ko.before
851074   24584   23112  898770   db6d2 btrfs.ko.after

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2014-09-17 13:37:14 -07:00
David Sterba 962a298f35 btrfs: kill the key type accessor helpers
btrfs_set_key_type and btrfs_key_type are used inconsistently along with
open coded variants. Other members of btrfs_key are accessed directly
without any helpers anyway.

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2014-09-17 13:37:12 -07:00
David Sterba 57cdc8db21 btrfs: cleanup ino cache members of btrfs_root
The naming is confusing, generic yet used for a specific cache. Add a
prefix 'ino_' or rename appropriately.

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2014-09-17 13:37:09 -07:00
Dan Carpenter c47ca32d3a Btrfs: kfree()ing ERR_PTRs
The "inherit" in btrfs_ioctl_snap_create_v2() and "vol_args" in
btrfs_ioctl_rm_dev() are ERR_PTRs so we can't call kfree() on them.

These kind of bugs are "One Err Bugs" where there is just one error
label that does everything.  I could set the "inherit = NULL" and keep
the single out label but it ends up being more complicated that way.  It
makes the code simpler to re-order the unwind so it's in the mirror
order of the allocation and introduce some new error labels.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-09-08 13:56:42 -07:00
Chris Mason e9512d72e8 Btrfs: fix autodefrag with compression
The autodefrag code skips defrag when two extents are adjacent.  But one
big advantage for autodefrag is cutting down on the number of small
extents, even when they are adjacent.  This commit changes it to defrag
all small extents.

Signed-off-by: Chris Mason <clm@fb.com>
2014-08-27 08:45:37 -07:00
Filipe Manana 62e2390e1a Btrfs: clone, don't create invalid hole extent map
When cloning a file that consists of an inline extent, we were creating
an extent map that represents a non-existing trailing hole starting at a
file offset that isn't a multiple of the sector size. This happened because
when processing an inline extent we weren't aligning the extent's length to
the sector size, and therefore incorrectly treating the range
[inline_extent_length; sector_size[ as a hole.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Satoru Takeuchi <takeuchi_satoru@jp.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-08-21 07:55:26 -07:00
Filipe Manana 9c3b306e1c Btrfs: race free update of commit root for ro snapshots
This is a better solution for the problem addressed in the following
commit:

    Btrfs: update commit root on snapshot creation after orphan cleanup
    (3821f34888)

The previous solution wasn't the best because of 2 reasons:

    1) It added another full transaction commit, which is more expensive
       than just swapping the commit root with the root;

    2) If a reboot happened after the first transaction commit (the one
       that creates the snapshot) and before the second transaction commit,
       then we would end up with the same problem if a send using that
       snapshot was requested before the first transaction commit after
       the reboot.

This change addresses those 2 issues. The second issue is addressed by
switching the commit root in the dentry lookup VFS callback, which is
also called by the snapshot/subvol creation ioctl and performs orphan
cleanup if needed. Like the vfs, the ioctl locks the parent inode too,
preventing race issues between a dentry lookup and snapshot creation.

Cc: Alex Lyakas <alex.btrfs@zadarastorage.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-08-21 07:55:21 -07:00
Linus Torvalds b82207b8e8 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs fixes from Chris Mason:
 "We've queued up a few fixes in my for-linus branch"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  Btrfs: fix crash when starting transaction
  Btrfs: fix btrfs_print_leaf for skinny metadata
  Btrfs: fix race of using total_bytes_pinned
  btrfs: use E2BIG instead of EIO if compression does not help
  btrfs: remove stale comment from btrfs_flush_all_pending_stuffs
  Btrfs: fix use-after-free when cloning a trailing file hole
  btrfs: fix null pointer dereference in btrfs_show_devname when name is null
  btrfs: fix null pointer dereference in clone_fs_devices when name is null
  btrfs: fix nossd and ssd_spread mount option regression
  Btrfs: fix race between balance recovery and root deletion
  Btrfs: atomically set inode->i_flags in btrfs_update_iflags
  btrfs: only unlock block in verify_parent_transid if we locked it
  Btrfs: assert send doesn't attempt to start transactions
  btrfs compression: reuse recently used workspace
  Btrfs: fix crash when mounting raid5 btrfs with missing disks
  btrfs: create sprout should rename fsid on the sysfs as well
  btrfs: dev replace should replace the sysfs entry
  btrfs: dev add should add its sysfs entry
  btrfs: dev delete should remove sysfs entry
  btrfs: rename add_device_membership to btrfs_kobj_add_device
2014-07-04 08:53:53 -07:00
Filipe Manana 14f5979633 Btrfs: fix use-after-free when cloning a trailing file hole
The transaction handle was being used after being freed.

Cc: Chris Mason <clm@fb.com>
Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-07-03 07:04:10 -07:00
Filipe Manana 3cc7939255 Btrfs: atomically set inode->i_flags in btrfs_update_iflags
This change is based on the corresponding recent change for ext4:

  ext4: atomically set inode->i_flags in ext4_set_inode_flags()

That has the following commit message that applies to btrfs as well:

  "Use cmpxchg() to atomically set i_flags instead of clearing out the
   S_IMMUTABLE, S_APPEND, etc. flags and then setting them from the
   EXT4_IMMUTABLE_FL, EXT4_APPEND_FL flags, since this opens up a race
   where an immutable file has the immutable flag cleared for a brief
   window of time."

Replacing EXT4_IMMUTABLE_FL and EXT4_APPEND_FL with BTRFS_INODE_IMMUTABLE
and BTRFS_INODE_APPEND, respectively.

Reviewed-by: David Sterba <dsterba@suse.cz>
Reviewed-by: Satoru Takeuchi <takeuchi_satoru@jp.fujitsu.com>
Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-07-03 07:03:23 -07:00
Linus Torvalds 16d52ef7c0 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull more btrfs updates from Chris Mason:
 "This has a few fixes since our last pull and a new ioctl for doing
  btree searches from userland.  It's very similar to the existing
  ioctl, but lets us return larger items back down to the app"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  btrfs: fix error handling in create_pending_snapshot
  btrfs: fix use of uninit "ret" in end_extent_writepage()
  btrfs: free ulist in qgroup_shared_accounting() error path
  Btrfs: fix qgroups sanity test crash or hang
  btrfs: prevent RCU warning when dereferencing radix tree slot
  Btrfs: fix unfinished readahead thread for raid5/6 degraded mounting
  btrfs: new ioctl TREE_SEARCH_V2
  btrfs: tree_search, search_ioctl: direct copy to userspace
  btrfs: new function read_extent_buffer_to_user
  btrfs: tree_search, copy_to_sk: return needed size on EOVERFLOW
  btrfs: tree_search, copy_to_sk: return EOVERFLOW for too small buffer
  btrfs: tree_search, search_ioctl: accept varying buffer
  btrfs: tree_search: eliminate redundant nr_items check
2014-06-14 19:48:43 -05:00
Gerhard Heift cc68a8a5a4 btrfs: new ioctl TREE_SEARCH_V2
This new ioctl call allows the user to supply a buffer of varying size in which
a tree search can store its results. This is much more flexible if you want to
receive items which are larger than the current fixed buffer of 3992 bytes or
if you want to fetch more items at once. Items larger than this buffer are for
example some of the type EXTENT_CSUM.

Signed-off-by: Gerhard Heift <Gerhard@Heift.Name>
Signed-off-by: Chris Mason <clm@fb.com>
Acked-by: David Sterba <dsterba@suse.cz>
2014-06-13 09:52:19 -07:00
Gerhard Heift ba346b357d btrfs: tree_search, search_ioctl: direct copy to userspace
By copying each found item seperatly to userspace, we do not need extra
buffer in the kernel.

Signed-off-by: Gerhard Heift <Gerhard@Heift.Name>
Signed-off-by: Chris Mason <clm@fb.com>
Acked-by: David Sterba <dsterba@suse.cz>
2014-06-12 18:22:05 -07:00
Gerhard Heift 9b6e817d02 btrfs: tree_search, copy_to_sk: return needed size on EOVERFLOW
If an item in tree_search is too large to be stored in the given buffer, return
the needed size (including the header).

Signed-off-by: Gerhard Heift <Gerhard@Heift.Name>
Signed-off-by: Chris Mason <clm@fb.com>
Acked-by: David Sterba <dsterba@suse.cz>
2014-06-12 18:21:47 -07:00
Gerhard Heift 8f5f6178f3 btrfs: tree_search, copy_to_sk: return EOVERFLOW for too small buffer
In copy_to_sk, if an item is too large for the given buffer, it now returns
-EOVERFLOW instead of copying a search_header with len = 0. For backward
compatibility for the first item it still copies such a header to the buffer,
but not any other following items, which could have fitted.

tree_search changes -EOVERFLOW back to 0 to behave similiar to the way it
behaved before this patch.

Signed-off-by: Gerhard Heift <Gerhard@Heift.Name>
Signed-off-by: Chris Mason <clm@fb.com>
Acked-by: David Sterba <dsterba@suse.cz>
2014-06-12 18:21:39 -07:00
Gerhard Heift 1254444288 btrfs: tree_search, search_ioctl: accept varying buffer
rewrite search_ioctl to accept a buffer with varying size

Signed-off-by: Gerhard Heift <Gerhard@Heift.Name>
Signed-off-by: Chris Mason <clm@fb.com>
Acked-by: David Sterba <dsterba@suse.cz>
2014-06-12 18:21:26 -07:00
Gerhard Heift 25c9bc2e2b btrfs: tree_search: eliminate redundant nr_items check
If the amount of items reached the given limit of nr_items, we can leave
copy_to_sk without updating the key. Also by returning 1 we leave the loop in
search_ioctl without rechecking if we reached the given limit.

Signed-off-by: Gerhard Heift <Gerhard@Heift.Name>
Signed-off-by: Chris Mason <clm@fb.com>
Acked-by: David Sterba <dsterba@suse.cz>
2014-06-12 18:20:39 -07:00
Linus Torvalds 859862ddd2 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs updates from Chris Mason:
 "The biggest change here is Josef's rework of the btrfs quota
  accounting, which improves the in-memory tracking of delayed extent
  operations.

  I had been working on Btrfs stack usage for a while, mostly because it
  had become impossible to do long stress runs with slab, lockdep and
  pagealloc debugging turned on without blowing the stack.  Even though
  you upgraded us to a nice king sized stack, I kept most of the
  patches.

  We also have some very hard to find corruption fixes, an awesome sysfs
  use after free, and the usual assortment of optimizations, cleanups
  and other fixes"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (80 commits)
  Btrfs: convert smp_mb__{before,after}_clear_bit
  Btrfs: fix scrub_print_warning to handle skinny metadata extents
  Btrfs: make fsync work after cloning into a file
  Btrfs: use right type to get real comparison
  Btrfs: don't check nodes for extent items
  Btrfs: don't release invalid page in btrfs_page_exists_in_range()
  Btrfs: make sure we retry if page is a retriable exception
  Btrfs: make sure we retry if we couldn't get the page
  btrfs: replace EINVAL with EOPNOTSUPP for dev_replace raid56
  trivial: fs/btrfs/ioctl.c: fix typo s/substract/subtract/
  Btrfs: fix leaf corruption after __btrfs_drop_extents
  Btrfs: ensure btrfs_prev_leaf doesn't miss 1 item
  Btrfs: fix clone to deal with holes when NO_HOLES feature is enabled
  btrfs: free delayed node outside of root->inode_lock
  btrfs: replace EINVAL with ERANGE for resize when ULLONG_MAX
  Btrfs: fix transaction leak during fsync call
  btrfs: Avoid trucating page or punching hole in a already existed hole.
  Btrfs: update commit root on snapshot creation after orphan cleanup
  Btrfs: ioctl, don't re-lock extent range when not necessary
  Btrfs: avoid visiting all extent items when cloning a range
  ...
2014-06-11 09:22:21 -07:00
Filipe Manana 7ffbb598a0 Btrfs: make fsync work after cloning into a file
When cloning into a file, we were correctly replacing the extent
items in the target range and removing the extent maps. However
we weren't replacing the extent maps with new ones that point to
the new extents - as a consequence, an incremental fsync (when the
inode doesn't have the full sync flag) was a NOOP, since it relies
on the existence of extent maps in the modified list of the inode's
extent map tree, which was empty. Therefore add new extent maps to
reflect the target clone range.

A test case for xfstests follows.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-06-09 17:21:16 -07:00
Antonio Ospite 9391558411 trivial: fs/btrfs/ioctl.c: fix typo s/substract/subtract/
Signed-off-by: Antonio Ospite <ao2@ao2.it>
Cc: Chris Mason <clm@fb.com>
Cc: Josef Bacik <jbacik@fb.com>
Cc: linux-btrfs@vger.kernel.org
Signed-off-by: Chris Mason <clm@fb.com>
2014-06-09 17:21:11 -07:00
Filipe Manana f82a9901b0 Btrfs: fix clone to deal with holes when NO_HOLES feature is enabled
If the NO_HOLES feature is enabled holes don't have file extent items in
the btree that represent them anymore. This made the clone operation
ignore the gaps that exist between consecutive file extent items and
therefore not create the holes at the destination. When not using the
NO_HOLES feature, the holes were created at the destination.

A test case for xfstests follows.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-06-09 17:21:09 -07:00
Gui Hecheng 902c68a4da btrfs: replace EINVAL with ERANGE for resize when ULLONG_MAX
To be accurate about the error case,
if the new size is beyond ULLONG_MAX, return ERANGE instead of EINVAL.

Signed-off-by: Gui Hecheng <guihc.fnst@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-06-09 17:21:07 -07:00
Filipe Manana 3821f34888 Btrfs: update commit root on snapshot creation after orphan cleanup
On snapshot creation (either writable or read-only), we do orphan cleanup
against the root of the snapshot. If the cleanup did remove any orphans,
then the current root node will be different from the commit root node
until the next transaction commit happens.

A send operation always uses the commit root of a snapshot - this means
it will see the orphans if it starts computing the send stream before the
next transaction commit happens (triggered by a timer or sync() for .e.g),
which is when the commit root gets assigned a reference to current root,
where the orphans are not visible anymore. The consequence of send seeing
the orphans is explained below.

For example:

    mkfs.btrfs -f /dev/sdd
    mount -o commit=999 /dev/sdd /mnt

    # open a file with O_TMPFILE and leave it open
    # write some data to the file
    btrfs subvolume snapshot -r /mnt /mnt/snap1

    btrfs send /mnt/snap1 -f /tmp/send.data

The send operation will fail with the following error:

    ERROR: send ioctl failed with -116: Stale file handle

What happens here is that our snapshot has an orphan inode still visible
through the commit root, that corresponds to the tmpfile. However send
will attempt to call inode.c:btrfs_iget(), with the goal of reading the
file's data, which will return -ESTALE because it will use the current
root (and not the commit root) of the snapshot.

Of course, there are other cases where we can get orphans, but this
example using a tmpfile makes it much easier to reproduce the issue.

Therefore on snapshot creation, after calling btrfs_orphan_cleanup, if
the commit root is different from the current root, just commit the
transaction associated with the snapshot's root (if it exists), so that
a send will not see any orphans that don't exist anymore. This also
guarantees a send will always see the same content regardless of whether
a transaction commit happened already before the send was requested and
after the orphan cleanup (meaning the commit root and current roots are
the same) or it hasn't happened yet (commit and current roots are
different).

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-06-09 17:21:05 -07:00
Filipe Manana ff5df9b884 Btrfs: ioctl, don't re-lock extent range when not necessary
In ioctl.c:lock_extent_range(), after locking our target range, the
ordered extent that btrfs_lookup_first_ordered_extent() returns us
may not overlap our target range at all. In this case we would just
unlock our target range, wait for any new ordered extents that overlap
the range to complete, lock again the range and repeat all these steps
until we don't get any ordered extent and the delalloc flag isn't set
in the io tree for our target range.

Therefore just stop if we get an ordered extent that doesn't overlap
our target range and the dealalloc flag isn't set for the range in
the inode's io tree.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-06-09 17:21:04 -07:00
Filipe Manana 2c463823cb Btrfs: avoid visiting all extent items when cloning a range
When cloning a range of a file, we were visiting all the extent items in
the btree that belong to our source inode. We don't need to visit those
extent items that don't overlap the range we are cloning, as doing so only
makes us waste time and do unnecessary btree navigations (btrfs_next_leaf)
for inodes that have a large number of file extent items in the btree.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-06-09 17:21:04 -07:00
Filipe Manana c55bfa67e9 Btrfs: set dead flag on the right root when destroying snapshot
We were setting the BTRFS_ROOT_SUBVOL_DEAD flag on the root of the
parent of our target snapshot, instead of setting it in the target
snapshot's root.

This is easy to observe by running the following scenario:

    mkfs.btrfs -f /dev/sdd
    mount /dev/sdd /mnt

    btrfs subvolume create /mnt/first_subvol
    btrfs subvolume snapshot -r /mnt /mnt/mysnap1

    btrfs subvolume delete /mnt/first_subvol
    btrfs subvolume snapshot -r /mnt /mnt/mysnap2

    btrfs send -p /mnt/mysnap1 /mnt/mysnap2 -f /tmp/send.data

The send command failed because the send ioctl returned -EPERM.
A test case for xfstests follows.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2014-06-09 17:21:03 -07:00
Filipe Manana c125b8bff1 Btrfs: ensure readers see new data after a clone operation
We were cleaning the clone target file range from the page cache before
we did replace the file extent items in the fs tree. This was racy,
as right after cleaning the relevant range from the page cache and before
replacing the file extent items, a read against that range could be
performed by another task and populate again the page cache with stale
data (stale after the cloning finishes). This would result in reads after
the clone operation successfully finishes to get old data (and potentially
for a very long time). Therefore evict the pages after replacing the file
extent items, so that subsequent reads will always get the new data.

Similarly, we were prone to races while cloning the file extent items
because we weren't locking the target range and wait for any existing
ordered extents against that range to complete. It was possible that
after cloning the extent items, a write operation that was performed
before the clone operation and overlaps the same range, would end up
undoing all or part of the work the clone operation did (a worker task
running inode.c:btrfs_finish_ordered_io). Therefore lock the target
range in the io tree, wait for all pending ordered extents against that
range to finish and then safely perform the cloning.

The issue of reading stale data after the clone operation is easy to
reproduce by running the following C program in a loop until it exits
with return value 1.

 #include <unistd.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <errno.h>
 #include <pthread.h>
 #include <fcntl.h>
 #include <assert.h>
 #include <asm/types.h>
 #include <linux/ioctl.h>
 #include <sys/stat.h>
 #include <sys/types.h>
 #include <sys/ioctl.h>

 #define SRC_FILE "/mnt/sdd/foo"
 #define DST_FILE "/mnt/sdd/bar"
 #define FILE_SIZE (16 * 1024)
 #define PATTERN_SRC 'X'
 #define PATTERN_DST 'Y'

struct btrfs_ioctl_clone_range_args {
	__s64 src_fd;
	__u64 src_offset, src_length;
	__u64 dest_offset;
};

 #define BTRFS_IOCTL_MAGIC 0x94
 #define BTRFS_IOC_CLONE_RANGE _IOW(BTRFS_IOCTL_MAGIC, 13, \
				   struct btrfs_ioctl_clone_range_args)

static pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;
static int clone_done = 0;
static int reader_ready = 0;
static int stale_data = 0;

static void *reader_loop(void *arg)
{
	char buf[4096], want_buf[4096];

	memset(want_buf, PATTERN_SRC, 4096);
	pthread_mutex_lock(&mutex);
	reader_ready = 1;
	pthread_mutex_unlock(&mutex);

	while (1) {
		int done, fd, ret;

		fd = open(DST_FILE, O_RDONLY);
		assert(fd != -1);

		pthread_mutex_lock(&mutex);
		done = clone_done;
		pthread_mutex_unlock(&mutex);

		ret = read(fd, buf, 4096);
		assert(ret == 4096);
		close(fd);

		if (done) {
			ret = memcmp(buf, want_buf, 4096);
			if (ret == 0) {
				printf("Found new content\n");
			} else {
				printf("Found old content\n");
				pthread_mutex_lock(&mutex);
				stale_data = 1;
				pthread_mutex_unlock(&mutex);
			}
			break;
		}
	}
	return NULL;
}

int main(int argc, char *argv[])
{
	pthread_t reader;
	int ret, i, fd;
	struct btrfs_ioctl_clone_range_args clone_args;
	int fd1, fd2;

	ret = remove(SRC_FILE);
	if (ret == -1 && errno != ENOENT) {
		fprintf(stderr, "Error deleting src file: %s\n", strerror(errno));
		return 1;
	}
	ret = remove(DST_FILE);
	if (ret == -1 && errno != ENOENT) {
		fprintf(stderr, "Error deleting dst file: %s\n", strerror(errno));
		return 1;
	}

	fd = open(SRC_FILE, O_CREAT | O_WRONLY | O_TRUNC, S_IRWXU);
	assert(fd != -1);
	for (i = 0; i < FILE_SIZE; i++) {
		char c = PATTERN_SRC;
		ret = write(fd, &c, 1);
		assert(ret == 1);
	}
	close(fd);
	fd = open(DST_FILE, O_CREAT | O_WRONLY | O_TRUNC, S_IRWXU);
	assert(fd != -1);
	for (i = 0; i < FILE_SIZE; i++) {
		char c = PATTERN_DST;
		ret = write(fd, &c, 1);
		assert(ret == 1);
	}
	close(fd);
        sync();

	ret = pthread_create(&reader, NULL, reader_loop, NULL);
	assert(ret == 0);
	while (1) {
		int r;
		pthread_mutex_lock(&mutex);
		r = reader_ready;
		pthread_mutex_unlock(&mutex);
		if (r) break;
	}

	fd1 = open(SRC_FILE, O_RDONLY);
	if (fd1 < 0) {
		fprintf(stderr, "Error open src file: %s\n", strerror(errno));
		return 1;
	}
	fd2 = open(DST_FILE, O_RDWR);
	if (fd2 < 0) {
		fprintf(stderr, "Error open dst file: %s\n", strerror(errno));
		return 1;
	}
	clone_args.src_fd = fd1;
	clone_args.src_offset = 0;
	clone_args.src_length = 4096;
	clone_args.dest_offset = 0;
	ret = ioctl(fd2, BTRFS_IOC_CLONE_RANGE, &clone_args);
	assert(ret == 0);
	close(fd1);
	close(fd2);

	pthread_mutex_lock(&mutex);
	clone_done = 1;
	pthread_mutex_unlock(&mutex);
	ret = pthread_join(reader, NULL);
	assert(ret == 0);

	pthread_mutex_lock(&mutex);
	ret = stale_data ? 1 : 0;
	pthread_mutex_unlock(&mutex);
	return ret;
}

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-06-09 17:21:02 -07:00
ZhangZhen 58dfae6365 btrfs: replace simple_strtoull() with kstrtoull()
use the newer and more pleasant kstrtoull() to replace simple_strtoull(),
because simple_strtoull() is marked for obsoletion.

Signed-off-by: Zhang Zhen <zhenzhang.zhang@huawei.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-06-09 17:20:51 -07:00
Josef Bacik fcebe4562d Btrfs: rework qgroup accounting
Currently qgroups account for space by intercepting delayed ref updates to fs
trees.  It does this by adding sequence numbers to delayed ref updates so that
it can figure out how the tree looked before the update so we can adjust the
counters properly.  The problem with this is that it does not allow delayed refs
to be merged, so if you say are defragging an extent with 5k snapshots pointing
to it we will thrash the delayed ref lock because we need to go back and
manually merge these things together.  Instead we want to process quota changes
when we know they are going to happen, like when we first allocate an extent, we
free a reference for an extent, we add new references etc.  This patch
accomplishes this by only adding qgroup operations for real ref changes.  We
only modify the sequence number when we need to lookup roots for bytenrs, this
reduces the amount of churn on the sequence number and allows us to merge
delayed refs as we add them most of the time.  This patch encompasses a bunch of
architectural changes

1) qgroup ref operations: instead of tracking qgroup operations through the
delayed refs we simply add new ref operations whenever we notice that we need to
when we've modified the refs themselves.

2) tree mod seq:  we no longer have this separation of major/minor counters.
this makes the sequence number stuff much more sane and we can remove some
locking that was needed to protect the counter.

3) delayed ref seq: we now read the tree mod seq number and use that as our
sequence.  This means each new delayed ref doesn't have it's own unique sequence
number, rather whenever we go to lookup backrefs we inc the sequence number so
we can make sure to keep any new operations from screwing up our world view at
that given point.  This allows us to merge delayed refs during runtime.

With all of these changes the delayed ref stuff is a little saner and the qgroup
accounting stuff no longer goes negative in some cases like it was before.
Thanks,

Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-06-09 17:20:48 -07:00
Miao Xie 27cdeb7096 Btrfs: use bitfield instead of integer data type for the some variants in btrfs_root
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-06-09 17:20:40 -07:00
David Sterba 61155aa04e btrfs: assert that send is not in progres before root deletion
CC: Miao Xie <miaox@cn.fujitsu.com>
CC: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2014-06-09 17:20:32 -07:00
David Sterba 521e0546c9 btrfs: protect snapshots from deleting during send
The patch "Btrfs: fix protection between send and root deletion"
(18f687d538) does not actually prevent to delete the snapshot
and just takes care during background cleaning, but this seems rather
user unfriendly, this patch implements the idea presented in

http://www.spinics.net/lists/linux-btrfs/msg30813.html

- add an internal root_item flag to denote a dead root
- check if the send_in_progress is set and refuse to delete, otherwise
  set the flag and proceed
- check the flag in send similar to the btrfs_root_readonly checks, for
  all involved roots

The root lookup in send via btrfs_read_fs_root_no_name will check if the
root is really dead or not. If it is, ENOENT, aborted send. If it's
alive, it's protected by send_in_progress, send can continue.

CC: Miao Xie <miaox@cn.fujitsu.com>
CC: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2014-06-09 17:20:31 -07:00
David Sterba e4ef90ff61 btrfs: make FS_INFO ioctl available to anyone
This ioctl provides basic info about the filesystem that can be obtained
in other ways (eg. sysfs), there's no reason to restrict it to
CAP_SYSADMIN.

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2014-06-09 17:20:29 -07:00
David Sterba 7d6213c5a7 btrfs: make DEV_INFO ioctl available to anyone
This ioctl provides basic info about the devices that can be obtained in
other ways (eg. sysfs), there's no reason to restrict it to
CAP_SYSADMIN.

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2014-06-09 17:20:28 -07:00
David Sterba 80a773fbfc btrfs: retrieve more info from FS_INFO ioctl
Provide the basic information about filesystem through the ioctl:
* b-tree node size (same as leaf size)
* sector size
* expected alignment of CLONE_RANGE and EXTENT_SAME ioctl arguments

Backward compatibility: if the values are 0, kernel does not provide
this information, the applications should ignore them.

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2014-06-09 17:20:27 -07:00
Linus Torvalds 776edb5931 Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip into next
Pull core locking updates from Ingo Molnar:
 "The main changes in this cycle were:

   - reduced/streamlined smp_mb__*() interface that allows more usecases
     and makes the existing ones less buggy, especially in rarer
     architectures

   - add rwsem implementation comments

   - bump up lockdep limits"

* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (33 commits)
  rwsem: Add comments to explain the meaning of the rwsem's count field
  lockdep: Increase static allocations
  arch: Mass conversion of smp_mb__*()
  arch,doc: Convert smp_mb__*()
  arch,xtensa: Convert smp_mb__*()
  arch,x86: Convert smp_mb__*()
  arch,tile: Convert smp_mb__*()
  arch,sparc: Convert smp_mb__*()
  arch,sh: Convert smp_mb__*()
  arch,score: Convert smp_mb__*()
  arch,s390: Convert smp_mb__*()
  arch,powerpc: Convert smp_mb__*()
  arch,parisc: Convert smp_mb__*()
  arch,openrisc: Convert smp_mb__*()
  arch,mn10300: Convert smp_mb__*()
  arch,mips: Convert smp_mb__*()
  arch,metag: Convert smp_mb__*()
  arch,m68k: Convert smp_mb__*()
  arch,m32r: Convert smp_mb__*()
  arch,ia64: Convert smp_mb__*()
  ...
2014-06-03 12:57:53 -07:00
Linus Torvalds 11da37b263 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull two btrfs fixes from Chris Mason:
 "This has two fixes that we've been testing for 3.16, but since both
  are safe and fix real bugs, it makes sense to send for 3.15 instead"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  Btrfs: send, fix incorrect ref access when using extrefs
  Btrfs: fix EIO on reading file after ioctl clone works on it
2014-05-22 05:40:13 +09:00
Liu Bo d3ecfcdf91 Btrfs: fix EIO on reading file after ioctl clone works on it
For inline data extent, we need to make its length aligned, otherwise,
we can get a phantom extent map which confuses readpages() to return -EIO.

This can be detected by xfstests/btrfs/035.

Reported-by: David Disseldorp <ddiss@suse.de>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-05-20 10:17:48 -07:00
Linus Torvalds 33c0022f0e Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs fixes from Chris Mason.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  Btrfs: limit the path size in send to PATH_MAX
  Btrfs: correctly set profile flags on seqlock retry
  Btrfs: use correct key when repeating search for extent item
  Btrfs: fix inode caching vs tree log
  Btrfs: fix possible memory leaks in open_ctree()
  Btrfs: avoid triggering bug_on() when we fail to start inode caching task
  Btrfs: move btrfs_{set,clear}_and_info() to ctree.h
  btrfs: replace error code from btrfs_drop_extents
  btrfs: Change the hole range to a more accurate value.
  btrfs: fix use-after-free in mount_subvol()
2014-04-27 13:26:28 -07:00
David Sterba 3f9e3df8da btrfs: replace error code from btrfs_drop_extents
There's a case which clone does not handle and used to BUG_ON instead,
(testcase xfstests/btrfs/035), now returns EINVAL. This error code is
confusing to the ioctl caller, as it normally signifies errorneous
arguments.

Change it to ENOPNOTSUPP which allows a fall back to copy instead of
clone. This does not affect the common reflink operation.

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2014-04-24 16:43:32 -07:00
Peter Zijlstra 4e857c58ef arch: Mass conversion of smp_mb__*()
Mostly scripted conversion of the smp_mb__* barriers.

Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/n/tip-55dhyhocezdw1dg7u19hmh1u@git.kernel.org
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-arch@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-04-18 14:20:48 +02:00
Linus Torvalds 3123bca719 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull second set of btrfs updates from Chris Mason:
 "The most important changes here are from Josef, fixing a btrfs
  regression in 3.14 that can cause corruptions in the extent allocation
  tree when snapshots are in use.

  Josef also fixed some deadlocks in send/recv and other assorted races
  when balance is running"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (23 commits)
  Btrfs: fix compile warnings on on avr32 platform
  btrfs: allow mounting btrfs subvolumes with different ro/rw options
  btrfs: export global block reserve size as space_info
  btrfs: fix crash in remount(thread_pool=) case
  Btrfs: abort the transaction when we don't find our extent ref
  Btrfs: fix EINVAL checks in btrfs_clone
  Btrfs: fix unlock in __start_delalloc_inodes()
  Btrfs: scrub raid56 stripes in the right way
  Btrfs: don't compress for a small write
  Btrfs: more efficient io tree navigation on wait_extent_bit
  Btrfs: send, build path string only once in send_hole
  btrfs: filter invalid arg for btrfs resize
  Btrfs: send, fix data corruption due to incorrect hole detection
  Btrfs: kmalloc() doesn't return an ERR_PTR
  Btrfs: fix snapshot vs nocow writting
  btrfs: Change the expanding write sequence to fix snapshot related bug.
  btrfs: make device scan less noisy
  btrfs: fix lockdep warning with reclaim lock inversion
  Btrfs: hold the commit_root_sem when getting the commit root during send
  Btrfs: remove transaction from send
  ...
2014-04-11 14:16:53 -07:00
David Sterba 36523e9512 btrfs: export global block reserve size as space_info
Introduce a block group type bit for a global reserve and fill the space
info for SPACE_INFO ioctl. This should replace the newly added ioctl
(01e219e806) to get just the 'size' part
of the global reserve, while the actual usage can be now visible in the
'btrfs fi df' output during ENOSPC stress.

The unpatched userspace tools will show the blockgroup as 'unknown'.

CC: Jeff Mahoney <jeffm@suse.com>
CC: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2014-04-07 10:41:53 -07:00
Chris Mason 3a29bc0928 Btrfs: fix EINVAL checks in btrfs_clone
btrfs_drop_extents can now return -EINVAL, but only one caller
in btrfs_clone was checking for it.  This adds it to the
caller for inline extents, which is where we really need it.

Signed-off-by: Chris Mason <clm@fb.com>
2014-04-07 09:08:50 -07:00
Gui Hecheng 9a40f1222a btrfs: filter invalid arg for btrfs resize
Originally following cmds will work:
	# btrfs fi resize -10A  <mnt>
	# btrfs fi resize -10Gaha <mnt>
Filter the arg by checking the return pointer of memparse.

Signed-off-by: Gui Hecheng <guihc.fnst@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-04-07 09:08:45 -07:00
Dan Carpenter 84dbeb87d1 Btrfs: kmalloc() doesn't return an ERR_PTR
The error handling was copy and pasted from memdup_user().  It should be
checking for NULL obviously.

Fixes: abccd00f8a ('btrfs: Fix 32/64-bit problem with BTRFS_SET_RECEIVED_SUBVOL ioctl')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-04-07 09:08:44 -07:00
Linus Torvalds 53c566625f Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs changes from Chris Mason:
 "This is a pretty long stream of bug fixes and performance fixes.

  Qu Wenruo has replaced the btrfs async threads with regular kernel
  workqueues.  We'll keep an eye out for performance differences, but
  it's nice to be using more generic code for this.

  We still have some corruption fixes and other patches coming in for
  the merge window, but this batch is tested and ready to go"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (108 commits)
  Btrfs: fix a crash of clone with inline extents's split
  btrfs: fix uninit variable warning
  Btrfs: take into account total references when doing backref lookup
  Btrfs: part 2, fix incremental send's decision to delay a dir move/rename
  Btrfs: fix incremental send's decision to delay a dir move/rename
  Btrfs: remove unnecessary inode generation lookup in send
  Btrfs: fix race when updating existing ref head
  btrfs: Add trace for btrfs_workqueue alloc/destroy
  Btrfs: less fs tree lock contention when using autodefrag
  Btrfs: return EPERM when deleting a default subvolume
  Btrfs: add missing kfree in btrfs_destroy_workqueue
  Btrfs: cache extent states in defrag code path
  Btrfs: fix deadlock with nested trans handles
  Btrfs: fix possible empty list access when flushing the delalloc inodes
  Btrfs: split the global ordered extents mutex
  Btrfs: don't flush all delalloc inodes when we doesn't get s_umount lock
  Btrfs: reclaim delalloc metadata more aggressively
  Btrfs: remove unnecessary lock in may_commit_transaction()
  Btrfs: remove the unnecessary flush when preparing the pages
  Btrfs: just do dirty page flush for the inode with compression before direct IO
  ...
2014-04-04 15:31:36 -07:00
Liu Bo 00fdf13a2e Btrfs: fix a crash of clone with inline extents's split
xfstests's btrfs/035 triggers a BUG_ON, which we use to detect the split
of inline extents in __btrfs_drop_extents().

For inline extents, we cannot duplicate another EXTENT_DATA item, because
it breaks the rule of inline extents, that is, 'start offset' needs to be 0.

We have set limitations for the source inode's compressed inline extents,
because it needs to decompress and recompress.  Now the destination inode's
inline extents also need similar limitations.

With this, xfstests btrfs/035 doesn't run into panic.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-03-21 17:35:18 -07:00
Filipe Manana f094c9bd3e Btrfs: less fs tree lock contention when using autodefrag
When finding new extents during an autodefrag, don't do so many fs tree
lookups to find an extent with a size smaller then the target treshold.
Instead, after each fs tree forward search immediately unlock upper
levels and process the entire leaf while holding a read lock on the leaf,
since our leaf processing is very fast.
This reduces lock contention, allowing for higher concurrency when other
tasks want to write/update items related to other inodes in the fs tree,
as we're not holding read locks on upper tree levels while processing the
leaf and we do less tree searches.

Test:

    sysbench --test=fileio --file-num=512 --file-total-size=16G \
       --file-test-mode=rndrw --num-threads=32 --file-block-size=32768 \
       --file-rw-ratio=3 --file-io-mode=sync --max-time=1800 \
       --max-requests=10000000000 [prepare|run]

(fileystem mounted with -o autodefrag, averages of 5 runs)

Before this change: 58.852Mb/sec throughtput, read 77.589Gb, written 25.863Gb
After this change:  63.034Mb/sec throughtput, read 83.102Gb, written 27.701Gb

Test machine: quad core intel i5-3570K, 32Gb of RAM, SSD.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-03-20 17:15:27 -07:00
Guangyu Sun 72de6b5393 Btrfs: return EPERM when deleting a default subvolume
The error message is confusing:

 # btrfs sub delete /mnt/mysub/
 Delete subvolume '/mnt/mysub'
 ERROR: cannot delete '/mnt/mysub' - Directory not empty

The error message does not make sense to me: It's not about deleting a
directory but it's a subvolume, and it doesn't matter if the subvolume is
empty or not.

Maybe EPERM or is more appropriate in this case, combined with an explanatory
kernel log message. (e.g. "subvolume with ID 123 cannot be deleted because
it is configured as default subvolume.")

Reported-by: Koen De Wit <koen.de.wit@oracle.com>
Signed-off-by: Guangyu Sun <guangyu.sun@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2014-03-20 17:15:27 -07:00
Filipe Manana 308d9800b2 Btrfs: cache extent states in defrag code path
When locking file ranges in the inode's io_tree, cache the first
extent state that belongs to the target range, so that when unlocking
the range we don't need to search in the io_tree again, reducing cpu
time and making and therefore holding the io_tree's lock for a shorter
period.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-03-20 17:15:27 -07:00
Miao Xie 6c255e67ce Btrfs: don't flush all delalloc inodes when we doesn't get s_umount lock
We needn't flush all delalloc inodes when we doesn't get s_umount lock,
or we would make the tasks wait for a long time.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:27 -04:00
Miao Xie 8257b2dc3c Btrfs: introduce btrfs_{start, end}_nocow_write() for each subvolume
If the snapshot creation happened after the nocow write but before the dirty
data flush, we would fail to flush the dirty data because of no space.

So we must keep track of when those nocow write operations start and when they
end, if there are nocow writers, the snapshot creators must wait. In order
to implement this function, I introduce btrfs_{start, end}_nocow_write(),
which is similar to mnt_{want,drop}_write().

These two functions are only used for nocow file write operations.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:22 -04:00
Filipe Manana e2127cf008 Btrfs: make defrag not fragment files when using prealloc extents
When using prealloc extents, a file defragment operation may actually
fragment the file and increase the amount of data space used by the file.
This change fixes that behaviour.

Example:

$ mkfs.btrfs -f /dev/sdb3
$ mount /dev/sdb3 /mnt
$ cd /mnt
$ xfs_io -f -c 'falloc 0 1048576' foobar && sync
$ xfs_io -c 'pwrite -S 0xff -b 100000 5000 100000' foobar
$ xfs_io -c 'pwrite -S 0xac -b 100000 200000 100000' foobar
$ xfs_io -c 'pwrite -S 0xe1 -b 100000 900000 100000' foobar && sync

Before defragmenting the file:

$ btrfs filesystem df /mnt
Data, single: total=8.00MiB, used=1.25MiB
System, DUP: total=8.00MiB, used=16.00KiB
System, single: total=4.00MiB, used=0.00
Metadata, DUP: total=1.00GiB, used=112.00KiB
Metadata, single: total=8.00MiB, used=0.00

$ btrfs-debug-tree /dev/sdb3
(...)
	item 6 key (257 EXTENT_DATA 0) itemoff 15810 itemsize 53
		prealloc data disk byte 12845056 nr 1048576
		prealloc data offset 0 nr 4096
	item 7 key (257 EXTENT_DATA 4096) itemoff 15757 itemsize 53
		extent data disk byte 12845056 nr 1048576
		extent data offset 4096 nr 102400 ram 1048576
		extent compression 0
	item 8 key (257 EXTENT_DATA 106496) itemoff 15704 itemsize 53
		prealloc data disk byte 12845056 nr 1048576
		prealloc data offset 106496 nr 90112
	item 9 key (257 EXTENT_DATA 196608) itemoff 15651 itemsize 53
		extent data disk byte 12845056 nr 1048576
		extent data offset 196608 nr 106496 ram 1048576
		extent compression 0
	item 10 key (257 EXTENT_DATA 303104) itemoff 15598 itemsize 53
		prealloc data disk byte 12845056 nr 1048576
		prealloc data offset 303104 nr 593920
	item 11 key (257 EXTENT_DATA 897024) itemoff 15545 itemsize 53
		extent data disk byte 12845056 nr 1048576
		extent data offset 897024 nr 106496 ram 1048576
		extent compression 0
	item 12 key (257 EXTENT_DATA 1003520) itemoff 15492 itemsize 53
		prealloc data disk byte 12845056 nr 1048576
		prealloc data offset 1003520 nr 45056
(...)

Now defragmenting the file results in more data space used than before:

$ btrfs filesystem defragment -f foobar && sync
$ btrfs filesystem df /mnt
Data, single: total=8.00MiB, used=1.55MiB
System, DUP: total=8.00MiB, used=16.00KiB
System, single: total=4.00MiB, used=0.00
Metadata, DUP: total=1.00GiB, used=112.00KiB
Metadata, single: total=8.00MiB, used=0.00

And the corresponding file extent items are now no longer perfectly sequential
as before, and we're now needlessly using more space from data block groups:

$ btrfs-debug-tree /dev/sdb3
(...)
	item 6 key (257 EXTENT_DATA 0) itemoff 15810 itemsize 53
		extent data disk byte 12845056 nr 1048576
		extent data offset 0 nr 4096 ram 1048576
		extent compression 0
	item 7 key (257 EXTENT_DATA 4096) itemoff 15757 itemsize 53
		extent data disk byte 13893632 nr 102400
		extent data offset 0 nr 102400 ram 102400
		extent compression 0
	item 8 key (257 EXTENT_DATA 106496) itemoff 15704 itemsize 53
		extent data disk byte 12845056 nr 1048576
		extent data offset 106496 nr 90112 ram 1048576
		extent compression 0
	item 9 key (257 EXTENT_DATA 196608) itemoff 15651 itemsize 53
		extent data disk byte 13996032 nr 106496
		extent data offset 0 nr 106496 ram 106496
		extent compression 0
	item 10 key (257 EXTENT_DATA 303104) itemoff 15598 itemsize 53
		prealloc data disk byte 12845056 nr 1048576
		prealloc data offset 303104 nr 593920
	item 11 key (257 EXTENT_DATA 897024) itemoff 15545 itemsize 53
		extent data disk byte 14102528 nr 106496
		extent data offset 0 nr 106496 ram 106496
		extent compression 0
	item 12 key (257 EXTENT_DATA 1003520) itemoff 15492 itemsize 53
		extent data disk byte 12845056 nr 1048576
		extent data offset 1003520 nr 45056 ram 1048576
		extent compression 0
(...)

With this change, the above example will no longer cause allocation of new data
space nor change the sequentiality of the file extents, that is, defragment will
be effectless, leaving all extent items pointing to the extent starting at disk
byte 12845056.

In a 20Gb filesystem I had, mounted with the autodefrag option and 20 files of
400Mb each, initially consisting of a single prealloc extent of 400Mb, having
random writes happening at a low rate, lead to a total of over ~17Gb of data
space used, not far from eventually reaching an ENOSPC state.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:17 -04:00
Filipe Manana dec8ef9055 Btrfs: correctly flush data on defrag when compression is enabled
When the defrag flag BTRFS_DEFRAG_RANGE_START_IO is set and compression
enabled, we weren't flushing completely, as writing compressed extents
is a 2 steps process, one to compress the data and another one to write
the compressed data to disk.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:16 -04:00
Hugo Mills abccd00f8a btrfs: Fix 32/64-bit problem with BTRFS_SET_RECEIVED_SUBVOL ioctl
The structure for BTRFS_SET_RECEIVED_IOCTL packs differently on 32-bit
and 64-bit systems. This means that it is impossible to use btrfs
receive on a system with a 64-bit kernel and 32-bit userspace, because
the structure size (and hence the ioctl number) is different.

This patch adds a compatibility structure and ioctl to deal with the
above case.

Signed-off-by: Hugo Mills <hugo@carfax.org.uk>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:15:40 -04:00
Kusanagi Kouichi 23ad5b17dc btrfs: Return EXDEV for cross file system snapshot
EXDEV seems an appropriate error if an operation fails bacause it
crosses file system boundaries.

Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Kusanagi Kouichi <slash@ac.auone-net.jp>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:15:37 -04:00
Linus Torvalds 3962dfbe22 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs fixes from Chris Mason:
 "We have a small collection of fixes in my for-linus branch.

  The big thing that stands out is a revert of a new ioctl.  Users
  haven't shipped yet in btrfs-progs, and Dave Sterba found a better way
  to export the information"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  Btrfs: use right clone root offset for compressed extents
  btrfs: fix null pointer deference at btrfs_sysfs_add_one+0x105
  Btrfs: unset DCACHE_DISCONNECTED when mounting default subvol
  Btrfs: fix max_inline mount option
  Btrfs: fix a lockdep warning when cleaning up aborted transaction
  Revert "btrfs: add ioctl to export size of global metadata reservation"
2014-02-16 11:05:27 -08:00
Chris Mason 11bcac89c0 Revert "btrfs: add ioctl to export size of global metadata reservation"
This reverts commit 01e219e806.

David Sterba found a different way to provide these features without adding a new
ioctl.  We haven't released any progs with this ioctl yet, so I'm taking this out
for now until we finalize things.

Signed-off-by: Chris Mason <clm@fb.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
CC: Jeff Mahoney <jeffm@suse.com>
2014-02-14 13:42:13 -08:00
Linus Torvalds 9c1db77981 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs fixes from Chris Mason:
 "This is a small collection of fixes"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  Btrfs: fix data corruption when reading/updating compressed extents
  Btrfs: don't loop forever if we can't run because of the tree mod log
  btrfs: reserve no transaction units in btrfs_ioctl_set_features
  btrfs: commit transaction after setting label and features
  Btrfs: fix assert screwup for the pending move stuff
2014-02-09 11:12:26 -08:00
David Sterba 8051aa1a3d btrfs: reserve no transaction units in btrfs_ioctl_set_features
Added in patch "btrfs: add ioctls to query/change feature bits online"
modifications to superblock don't need to reserve metadata blocks when
starting a transaction.

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2014-02-08 17:57:15 -08:00
Jeff Mahoney d0270aca88 btrfs: commit transaction after setting label and features
The set_fslabel ioctl uses btrfs_end_transaction, which means it's
possible that the change will be lost if the system crashes, same for
the newly set features. Let's use btrfs_commit_transaction instead.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2014-02-08 17:57:15 -08:00
Linus Torvalds e7651b819e Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs updates from Chris Mason:
 "This is a pretty big pull, and most of these changes have been
  floating in btrfs-next for a long time.  Filipe's properties work is a
  cool building block for inheriting attributes like compression down on
  a per inode basis.

  Jeff Mahoney kicked in code to export filesystem info into sysfs.

  Otherwise, lots of performance improvements, cleanups and bug fixes.

  Looks like there are still a few other small pending incrementals, but
  I wanted to get the bulk of this in first"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (149 commits)
  Btrfs: fix spin_unlock in check_ref_cleanup
  Btrfs: setup inode location during btrfs_init_inode_locked
  Btrfs: don't use ram_bytes for uncompressed inline items
  Btrfs: fix btrfs_search_slot_for_read backwards iteration
  Btrfs: do not export ulist functions
  Btrfs: rework ulist with list+rb_tree
  Btrfs: fix memory leaks on walking backrefs failure
  Btrfs: fix send file hole detection leading to data corruption
  Btrfs: add a reschedule point in btrfs_find_all_roots()
  Btrfs: make send's file extent item search more efficient
  Btrfs: fix to catch all errors when resolving indirect ref
  Btrfs: fix protection between walking backrefs and root deletion
  btrfs: fix warning while merging two adjacent extents
  Btrfs: fix infinite path build loops in incremental send
  btrfs: undo sysfs when open_ctree() fails
  Btrfs: fix snprintf usage by send's gen_unique_name
  btrfs: fix defrag 32-bit integer overflow
  btrfs: sysfs: list the NO_HOLES feature
  btrfs: sysfs: don't show reserved incompat feature
  btrfs: call permission checks earlier in ioctls and return EPERM
  ...
2014-01-30 20:08:20 -08:00
Justin Maggard c41570c9d2 btrfs: fix defrag 32-bit integer overflow
When defragging a very large file, the cluster variable can wrap its 32-bit
signed int type and become negative, which eventually gets passed to
btrfs_force_ra() as a very large unsigned long value.  On 32-bit platforms,
this eventually results in an Oops from the SLAB allocator.

Change the cluster and max_cluster signed int variables to unsigned long to
match the readahead functions.  This also allows the min() comparison in
btrfs_defrag_file() to work as intended.

Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:20:43 -08:00
David Sterba bd60ea0fe9 btrfs: call permission checks earlier in ioctls and return EPERM
The owner and capability checks in IOC_SUBVOL_SETFLAGS and
SET_RECEIVED_SUBVOL should be called before any other checks are done.

Also unify the error code to EPERM.

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:20:41 -08:00
David Sterba d024206133 btrfs: restrict snapshotting to own subvolumes
Currently, any user can snapshot any subvolume if the path is accessible and
thus indirectly create and keep files he does not own under his direcotries.
This is not possible with traditional directories.

In security context, a user can snapshot root filesystem and pin any
potentially buggy binaries, even if the updates are applied.

All the snapshots are visible to the administrator, so it's possible to
verify if there are suspicious snapshots.

Another more practical problem is that any user can pin the space used
by eg. root and cause ENOSPC.

Original report:
https://bugs.launchpad.net/ubuntu/+source/apparmor/+bug/484786

CC: stable@vger.kernel.org
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:20:40 -08:00
Filipe David Borba Manana e4355f34ef Btrfs: faster file extent item search in clone ioctl
When we are looking for file extent items that intersect the cloning
range, for each one that falls completely outside the range, don't
release the path and do another full tree search - just move on
to the next slot and copy the file extent item into our buffer only
if the item intersects the cloning range.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:20:35 -08:00
Filipe David Borba Manana c57c2b3ed2 Btrfs: unlock inodes in correct order in clone ioctl
In the clone ioctl, when the source and target inodes are different,
we can acquire their mutexes in 2 possible different orders. After
we're done cloning, we were releasing the mutexes always in the same
order - the most correct way of doing it is to release them by the
reverse order they were acquired.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:20:30 -08:00
Liu Bo de6e820066 Btrfs: release subvolume's block_rsv before transaction commit
We don't have to keep subvolume's block_rsv during transaction commit,
and within transaction commit, we may also need the free space reclaimed
from this block_rsv to process delayed refs.

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>
2014-01-28 13:20:29 -08:00
Filipe David Borba Manana 63541927c8 Btrfs: add support for inode properties
This change adds infrastructure to allow for generic properties for
inodes. Properties are name/value pairs that can be associated with
inodes for different purposes. They are stored as xattrs with the
prefix "btrfs."

Properties can be inherited - this means when a directory inode has
inheritable properties set, these are added to new inodes created
under that directory. Further, subvolumes can also have properties
associated with them, and they can be inherited from their parent
subvolume. Naturally, directory properties have priority over subvolume
properties (in practice a subvolume property is just a regular
property associated with the root inode, objectid 256, of the
subvolume's fs tree).

This change also adds one specific property implementation, named
"compression", whose values can be "lzo" or "zlib" and it's an
inheritable property.

The corresponding changes to btrfs-progs were also implemented.
A patch with xfstests for this feature will follow once there's
agreement on this change/feature.

Further, the script at the bottom of this commit message was used to
do some benchmarks to measure any performance penalties of this feature.

Basically the tests correspond to:

Test 1 - create a filesystem and mount it with compress-force=lzo,
then sequentially create N files of 64Kb each, measure how long it took
to create the files, unmount the filesystem, mount the filesystem and
perform an 'ls -lha' against the test directory holding the N files, and
report the time the command took.

Test 2 - create a filesystem and don't use any compression option when
mounting it - instead set the compression property of the subvolume's
root to 'lzo'. Then create N files of 64Kb, and report the time it took.
The unmount the filesystem, mount it again and perform an 'ls -lha' like
in the former test. This means every single file ends up with a property
(xattr) associated to it.

Test 3 - same as test 2, but uses 4 properties - 3 are duplicates of the
compression property, have no real effect other than adding more work
when inheriting properties and taking more btree leaf space.

Test 4 - same as test 3 but with 10 properties per file.

Results (in seconds, and averages of 5 runs each), for different N
numbers of files follow.

* Without properties (test 1)

                    file creation time        ls -lha time
10 000 files              3.49                   0.76
100 000 files            47.19                   8.37
1 000 000 files         518.51                 107.06

* With 1 property (compression property set to lzo - test 2)

                    file creation time        ls -lha time
10 000 files              3.63                    0.93
100 000 files            48.56                    9.74
1 000 000 files         537.72                  125.11

* With 4 properties (test 3)

                    file creation time        ls -lha time
10 000 files              3.94                    1.20
100 000 files            52.14                   11.48
1 000 000 files         572.70                  142.13

* With 10 properties (test 4)

                    file creation time        ls -lha time
10 000 files              4.61                    1.35
100 000 files            58.86                   13.83
1 000 000 files         656.01                  177.61

The increased latencies with properties are essencialy because of:

*) When creating an inode, we now synchronously write 1 more item
   (an xattr item) for each property inherited from the parent dir
   (or subvolume). This could be done in an asynchronous way such
   as we do for dir intex items (delayed-inode.c), which could help
   reduce the file creation latency;

*) With properties, we now have larger fs trees. For this particular
   test each xattr item uses 75 bytes of leaf space in the fs tree.
   This could be less by using a new item for xattr items, instead of
   the current btrfs_dir_item, since we could cut the 'location' and
   'type' fields (saving 18 bytes) and maybe 'transid' too (saving a
   total of 26 bytes per xattr item) from the btrfs_dir_item type.

Also tried batching the xattr insertions (ignoring proper hash
collision handling, since it didn't exist) when creating files that
inherit properties from their parent inode/subvolume, but the end
results were (surprisingly) essentially the same.

Test script:

$ cat test.pl
  #!/usr/bin/perl -w

  use strict;
  use Time::HiRes qw(time);
  use constant NUM_FILES => 10_000;
  use constant FILE_SIZES => (64 * 1024);
  use constant DEV => '/dev/sdb4';
  use constant MNT_POINT => '/home/fdmanana/btrfs-tests/dev';
  use constant TEST_DIR => (MNT_POINT . '/testdir');

  system("mkfs.btrfs", "-l", "16384", "-f", DEV) == 0 or die "mkfs.btrfs failed!";

  # following line for testing without properties
  #system("mount", "-o", "compress-force=lzo", DEV, MNT_POINT) == 0 or die "mount failed!";

  # following 2 lines for testing with properties
  system("mount", DEV, MNT_POINT) == 0 or die "mount failed!";
  system("btrfs", "prop", "set", MNT_POINT, "compression", "lzo") == 0 or die "set prop failed!";

  system("mkdir", TEST_DIR) == 0 or die "mkdir failed!";
  my ($t1, $t2);

  $t1 = time();
  for (my $i = 1; $i <= NUM_FILES; $i++) {
      my $p = TEST_DIR . '/file_' . $i;
      open(my $f, '>', $p) or die "Error opening file!";
      $f->autoflush(1);
      for (my $j = 0; $j < FILE_SIZES; $j += 4096) {
          print $f ('A' x 4096) or die "Error writing to file!";
      }
      close($f);
  }
  $t2 = time();
  print "Time to create " . NUM_FILES . ": " . ($t2 - $t1) . " seconds.\n";
  system("umount", DEV) == 0 or die "umount failed!";
  system("mount", DEV, MNT_POINT) == 0 or die "mount failed!";

  $t1 = time();
  system("bash -c 'ls -lha " . TEST_DIR . " > /dev/null'") == 0 or die "ls failed!";
  $t2 = time();
  print "Time to ls -lha all files: " . ($t2 - $t1) . " seconds.\n";
  system("umount", DEV) == 0 or die "umount failed!";

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:20:24 -08:00
Wenliang Fan eb8052e015 fs/btrfs: Integer overflow in btrfs_ioctl_resize()
The local variable 'new_size' comes from userspace. If a large number
was passed, there would be an integer overflow in the following line:
	new_size = old_size + new_size;

Signed-off-by: Wenliang Fan <fanwlexca@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:20:11 -08:00
Frank Holton efe120a067 Btrfs: convert printk to btrfs_ and fix BTRFS prefix
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>
2014-01-28 13:20:05 -08:00
David Sterba 2c68653787 btrfs: Check read-only status of roots during send
All the subvolues that are involved in send must be read-only during the
whole operation. The ioctl SUBVOL_SETFLAGS could be used to change the
status to read-write and the result of send stream is undefined if the
data change unexpectedly.

Fix that by adding a refcount for all involved roots and verify that
there's no send in progress during SUBVOL_SETFLAGS ioctl call that does
read-only -> read-write transition.

We need refcounts because there are no restrictions on number of send
parallel operations currently run on a single subvolume, be it source,
parent or one of the multiple clone sources.

Kernel is silent when the RO checks fail and returns EPERM. The same set
of checks is done already in userspace before send starts.

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:20:01 -08:00
Tsutomu Itoh 5662344b3c Btrfs: fix error check of btrfs_lookup_dentry()
Clean up btrfs_lookup_dentry() to never return NULL, but PTR_ERR(-ENOENT)
instead. This keeps the return value convention consistent.

Callers who use btrfs_lookup_dentry() require a trivial update.

create_snapshot() in particular looks like it can also lose a BUG_ON(!inode)
which is not really needed - there seems less harm in returning ENOENT to
userspace at that point in the stack than there is to crash the machine.

Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:19:56 -08:00
Jeff Mahoney 01e219e806 btrfs: add ioctl to export size of global metadata reservation
btrfs filesystem df output will show the size of the metadata space
and how much of it is used, and the user assumes that the difference
is all usable space. Since that's not actually the case due to the
global metadata reservation, we should provide the full picture to the
user.

This patch adds an ioctl that exports the size of the global metadata
reservation so that btrfs filesystem df can report it.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:19:28 -08:00
Jeff Mahoney 3b02a68a63 btrfs: use feature attribute names to print better error messages
Now that we have the feature name strings available in the kernel via
the sysfs attributes, we can use them for printing better failure
messages from the ioctl path.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:19:28 -08:00
Jeff Mahoney 2eaa055fab btrfs: add ioctls to query/change feature bits online
There are some feature bits that require no offline setup and can
be enabled online. I've only reviewed extended irefs, but there will
probably be more.

We introduce three new ioctls:
- BTRFS_IOC_GET_SUPPORTED_FEATURES: query the kernel for supported features.
- BTRFS_IOC_GET_FEATURES: query the kernel for enabled features on a per-fs
  basis, as well as querying for which features are changeable with mounted.
- BTRFS_IOC_SET_FEATURES: change features on a per-fs basis.

We introduce two new masks per feature set (_SAFE_SET and _SAFE_CLEAR) that
allow us to define which features are safe to change at runtime.

The failure modes for BTRFS_IOC_SET_FEATURES are as follows:
- Enabling a completely unsupported feature: warns and returns -ENOTSUPP
- Enabling a feature that can only be done offline: warns and returns -EPERM

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:19:23 -08:00
Al Viro 1c1c8747cd btrfs: sanitize BTRFS_IOC_FILE_EXTENT_SAME
* don't assume that ->dest_count won't change between copy_from_user()
and memdup_user()
* use fdget instead of fget
* don't bother comparing superblocks when we'd already compared vfsmounts
* get rid of excessive goto
* use file_inode() instead of open-coding the sucker

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-01-25 03:13:03 -05:00
David Sterba e43f998e47 btrfs: call mnt_drop_write after interrupted subvol deletion
If btrfs_ioctl_snap_destroy blocks on the mutex and the process is
killed, mnt_write count is unbalanced and leads to unmountable
filesystem.

CC: stable@vger.kernel.org
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2013-12-12 07:11:38 -08:00
Al Viro 54563d41a5 btrfs: get rid of fdentry()
3 of 4 callers actually want file_inode()...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-11-15 09:18:14 -05:00
Chris Mason 46e0f66a0c btrfs: fix empty_zero_page misusage
Heiko Carstens noticed that btrfs was using empty_zero_page
incorrectly.  He explained:

	The definition of empty_zero_page is architecture specific.  It
	is (currently) either a character array, an unsigned long
	containing the address of the empty_zero_page, or even worse
	only the address of the struct page belonging to the
	empty_zero_page.

This commit changes btrfs to use a for-loop instead.  On x86
the resulting .ko is smaller, and we're no longer worrying about
how each arch builds its zeros.

Reported-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-11-15 09:17:47 -05:00
Miao Xie 91aef86f3b Btrfs: rename btrfs_start_all_delalloc_inodes
rename the function -- btrfs_start_all_delalloc_inodes(), and make its
name be compatible to btrfs_wait_ordered_roots(), since they are always
used at the same place.

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>
2013-11-11 22:13:58 -05:00
Miao Xie b02441999e Btrfs: don't wait for the completion of all the ordered extents
It is very likely that there are lots of ordered extents in the filesytem,
if we wait for the completion of all of them when we want to reclaim some
space for the metadata space reservation, we would be blocked for a long
time. The performance would drop down suddenly for a long time.

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>
2013-11-11 22:13:44 -05:00
Dulshani Gunawardhana 678712545b btrfs: Fix checkpatch.pl warning of spacing issues
Fix spacing issues detected via checkpatch.pl in accordance with the
kernel style guidelines.

Signed-off-by: Dulshani Gunawardhana <dulshani.gunawardhana89@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-11-11 22:12:31 -05:00
Dulshani Gunawardhana d9b0d9ba04 btrfs: Replace kmalloc with kmalloc_array
Replace kmalloc(size * nr, ) with kmalloc_array(nr, size), thus making
it easier to check is that the calculation doesn't wrap or return a smaller allocation

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>
2013-11-11 22:12:22 -05:00
Dulshani Gunawardhana b19e684393 btrfs: Remove redundant local zero structure
Remove redundant local zero structure, replacing it by the kernel's
global ZERO_PAGE.

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>
2013-11-11 22:11:39 -05:00
Zach Brown 8b558c5f09 btrfs: remove fs/btrfs/compat.h
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>
2013-11-11 22:03:19 -05:00
Geyslan G. Bem 229eed4348 btrfs: simplify kmalloc+copy_from_user to memdup_user
Use memdup_user rather than duplicating its implementation
This is a little bit restricted to reduce false positives

The semantic patch that makes this report is available
in scripts/coccinelle/api/memdup_user.cocci.

More information about semantic patching is available at
http://coccinelle.lip6.fr/

Signed-off-by: Geyslan G. Bem <geyslan@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-11-11 22:01:51 -05:00
Ilya Dryomov adfa97cbdf Btrfs: don't leak ioctl args in btrfs_ioctl_dev_replace
struct btrfs_ioctl_dev_replace_args memory is leaked if replace is
requested on a read-only filesystem.  Fix it.

Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-11-11 22:00:37 -05:00
Filipe David Borba Manana 6174d3cb43 Btrfs: remove unused max_key arg from btrfs_search_forward
It is not used for anything.

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>
2013-11-11 21:54:57 -05:00
Ross Kirk 0a4e558609 btrfs: remove unused parameter from btrfs_header_fsid
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>
2013-11-11 21:54:16 -05:00
Filipe David Borba Manana 9b19985986 Btrfs: fix sync fs to actually wait for all data to be persisted
Currently the fs sync function (super.c:btrfs_sync_fs()) doesn't
wait for delayed work to finish before returning success to the
caller. This change fixes this, ensuring that there's no data loss
if a power failure happens right after fs sync returns success to
the caller and before the next commit happens.

Steps to reproduce the data loss issue:

$ mkfs.btrfs -f /dev/sdb3
$ mount /dev/sdb3 /mnt/btrfs
$ perl -e '$d = ("\x41" x 6001); open($f,">","/mnt/btrfs/foobar"); print $f $d; close($f);' && btrfs fi sync /mnt/btrfs

Right after the btrfs fi sync command (a second or 2 for example), power
off the machine and reboot it. The file will be empty, as it can be verified
after mounting the filesystem and through btrfs-debug-tree:

$ btrfs-debug-tree /dev/sdb3 | egrep '\(257 INODE_ITEM 0\) itemoff' -B 3 -A 8
        item 3 key (256 DIR_INDEX 2) itemoff 3751 itemsize 36
                location key (257 INODE_ITEM 0) type FILE
                namelen 6 datalen 0 name: foobar
        item 4 key (257 INODE_ITEM 0) itemoff 3591 itemsize 160
                inode generation 7 transid 7 size 0 block group 0 mode 100644 links 1
        item 5 key (257 INODE_REF 256) itemoff 3575 itemsize 16
                inode ref index 2 namelen 6 name: foobar
checksum tree key (CSUM_TREE ROOT_ITEM 0)
leaf 29429760 items 0 free space 3995 generation 7 owner 7
fs uuid 6192815c-af2a-4b75-b3db-a959ffb6166e
chunk uuid b529c44b-938c-4d3d-910a-013b4700bcae
uuid tree key (UUID_TREE ROOT_ITEM 0)

After this patch, the data loss no longer happens after a power failure and
btrfs-debug-tree shows:

$ btrfs-debug-tree /dev/sdb3 | egrep '\(257 INODE_ITEM 0\) itemoff' -B 3 -A 8
	item 3 key (256 DIR_INDEX 2) itemoff 3751 itemsize 36
		location key (257 INODE_ITEM 0) type FILE
		namelen 6 datalen 0 name: foobar
	item 4 key (257 INODE_ITEM 0) itemoff 3591 itemsize 160
		inode generation 6 transid 6 size 6001 block group 0 mode 100644 links 1
	item 5 key (257 INODE_REF 256) itemoff 3575 itemsize 16
		inode ref index 2 namelen 6 name: foobar
	item 6 key (257 EXTENT_DATA 0) itemoff 3522 itemsize 53
		extent data disk byte 12845056 nr 8192
		extent data offset 0 nr 8192 ram 8192
		extent compression 0
checksum tree key (CSUM_TREE ROOT_ITEM 0)

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
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>
2013-11-11 21:53:08 -05:00
Mark Fasheh cbf8b8ca3e btrfs: change extent-same to copy entire argument struct
btrfs_ioctl_file_extent_same() uses __put_user_unaligned() to copy some data
back to it's argument struct. Unfortunately, not all architectures provide
__put_user_unaligned(), so compiles break on them if btrfs is selected.

Instead, just copy the whole struct in / out at the start and end of
operations, respectively.

Signed-off-by: Mark Fasheh <mfasheh@suse.de>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-09-21 11:05:31 -04:00
chandan 1cecf579d1 Btrfs: btrfs_ioctl_default_subvol: Revert back to toplevel subvolume when arg is 0
This patch makes it possible to set BTRFS_FS_TREE_OBJECTID as the default
subvolume by passing a subvolume id of 0.

Signed-off-by: chandan <chandan@linux.vnet.ibm.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-09-21 11:05:29 -04:00
Josef Bacik f0de181c9b Btrfs: kill delay_iput arg to the wait_ordered functions
This is a left over of how we used to wait for ordered extents, which was to
grab the inode and then run filemap flush on it.  However if we have an ordered
extent then we already are holding a ref on the inode, and we just use
btrfs_start_ordered_extent anyway, so there is no reason to have an extra ref on
the inode to start work on the ordered extent.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-09-21 11:05:27 -04:00
Anand Jain e57138b3e9 btrfs: return btrfs error code for dev excl ops err
now threads can return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS
as defined in btrfs.h for the dev excl operation error in
the FS, which means with this kernel would stop logging
(almost an user error) into the /var/log/messages

v2: accepts Josef' comment

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-09-01 08:16:35 -04:00
Filipe David Borba Manana f717175024 Btrfs: fix race conditions in BTRFS_IOC_FS_INFO ioctl
The handler for the ioctl BTRFS_IOC_FS_INFO was reading the
number of devices before acquiring the device list mutex.

This could lead to inconsistent results because the update of
the device list and the number of devices counter (amongst other
counters related to the device list) are updated in volumes.c
while holding the device list mutex - except for 2 places, one
was volumes.c:btrfs_prepare_sprout() and the other was
volumes.c:device_list_add().

For example, if we have 2 devices, with IDs 1 and 2 and then add
a new device, with ID 3, and while adding the device is in progress
an BTRFS_IOC_FS_INFO ioctl arrives, it could return a number of
devices of 2 and a max dev id of 3. This would be incorrect.

Also, this ioctl handler was reading the fsid while it can be
updated concurrently. This can happen when while a new device is
being added and the current filesystem is in seeding mode.
Example:

$ mkfs.btrfs -f /dev/sdb1
$ mkfs.btrfs -f /dev/sdb2
$ btrfstune -S 1 /dev/sdb1
$ mount /dev/sdb1 /mnt/test
$ btrfs device add /dev/sdb2 /mnt/test

If during the last step a BTRFS_IOC_FS_INFO ioctl was requested, it
could read an fsid that was never valid (some bits part of the old
fsid and others part of the new fsid). Also, it could read a number
of devices that doesn't match the number of devices in the list and
the max device id, as explained before.

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>
2013-09-01 08:16:25 -04:00
Geert Uytterhoeven b308bc2f05 Btrfs: Make btrfs_header_chunk_tree_uuid() return unsigned long
Internally, btrfs_header_chunk_tree_uuid() calculates an unsigned long, but
casts it to a pointer, while all callers cast it to unsigned long again.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-09-01 08:16:16 -04:00
Geert Uytterhoeven fba6aa7565 Btrfs: Make btrfs_header_fsid() return unsigned long
Internally, btrfs_header_fsid() calculates an unsigned long, but casts
it to a pointer, while all callers cast it to unsigned long again.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-09-01 08:16:15 -04:00
Geert Uytterhoeven c1c9ff7c94 Btrfs: Remove superfluous casts from u64 to unsigned long long
u64 is "unsigned long long" on all architectures now, so there's no need to
cast it when formatting it using the "ll" length modifier.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-09-01 08:16:08 -04:00
Stefan Behrens bbb651e469 Btrfs: don't allow the replace procedure on read only filesystems
If you start the replace procedure on a read only filesystem, at
the end the procedure fails to write the updated dev_items to the
chunk tree. The problem is that this error is not indicated except
for a WARN_ON(). If the user now thinks that everything was done
as expected and destroys the source device (with mkfs or with a
hammer). The next mount fails with "failed to read chunk root" and
the filesystem is gone.

This commit adds code to fail the attempt to start the replace
procedure if the filesystem is mounted read-only.

Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Cc: <stable@vger.kernel.org> # 3.10+
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-09-01 08:16:02 -04:00
Filipe David Borba Manana 633085c79c Btrfs: reset force_compress on btrfs_file_defrag failure
After we set force_compress with a new value (which was not being done
while holding the inode mutex), if an error happens and we jump to
the label out_ra, the force_compress property of the inode is not set
to BTRFS_COMPRESS_NONE (unlike in the case where no errors 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>
2013-09-01 08:16:00 -04:00