When page aligned start and len passed to extent_fiemap(), the result is
good, but when start and len is not aligned, e.g. start = 1 and len =
4095 is passed to extent_fiemap(), it returns no extent.

The problem is that start and len is all rounded down which causes the
problem. This patch will round down start and round up (start + len) to
return right extent.
Reported-by: NChandan Rajendra <chandan@linux.vnet.ibm.com>
Signed-off-by: NQu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-by: NDavid Sterba <dsterba@suse.cz>
Signed-off-by: NChris Mason <clm@fb.com>

btrfs_next_leaf() will use current leaf's last key to search
and then return a bigger one. So it may still return a file extent
item that is smaller than expected value and we will
get an overflow here for @em->len.

This is easy to reproduce for Btrfs Direct writting, it did not
cause any problem, because writting will re-insert right mapping later.

However, by hacking code to make DIO support compression, wrong extent
mapping is kept and it encounter merging failure(EEXIST) quickly.

Fix this problem by looping to find next file extent item that is bigger
than @start or we could not find anything more.
Signed-off-by: NWang Shilong <wangsl.fnst@cn.fujitsu.com>
Reviewed-by: NDavid Sterba <dsterba@suse.cz>
Signed-off-by: NChris Mason <clm@fb.com>

filemap_fdatawrite_range() expect the third arg to be @end
not @len, fix it.
Signed-off-by: NWang Shilong <wangsl.fnst@cn.fujitsu.com>
Reviewed-by: NDavid Sterba <dsterba@suse.cz>
Signed-off-by: NChris Mason <clm@fb.com>

The missing devices are accounted by its own fs device, for example
the missing devices in seed filesystem will be accounted by the fs device
of the seed filesystem, not by the new filesystem which is based on
the seed filesystem, so when we remove the missing device in the
seed filesystem, we should decrease the counter of its own fs device.
Fix it.
Signed-off-by: NMiao Xie <miaox@cn.fujitsu.com>
Signed-off-by: NChris Mason <clm@fb.com>

We forgot to zero some members in fs_devices when we create new fs_devices
from the one of the seed fs. It would cause the problem that we got wrong
chunk profile when allocating chunks. Fix it.
Signed-off-by: NMiao Xie <miaox@cn.fujitsu.com>
Signed-off-by: NChris Mason <clm@fb.com>

When FS in unmounted we need to check generation number as well
since devid+uuid combination could match with the missing replaced
disk when it reappears, and without this patch it might pair with
the replaced disk again.

 device_list_add() function is called in the following threads,
	mount device option
	mount argument
	ioctl BTRFS_IOC_SCAN_DEV (btrfs dev scan)
	ioctl BTRFS_IOC_DEVICES_READY (btrfs dev ready <dev>)
 they have been unit tested to work fine with this patch.

 If the user knows what he is doing and really want to pair with
 replaced disk (which is not a standard operation), then he should
 first clear the kernel btrfs device list in the memory by doing
 the module unload/load and followed with the mount -o device option.
Signed-off-by: NAnand Jain <anand.jain@oracle.com>
Signed-off-by: NWang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: NMiao Xie <miaox@cn.fujitsu.com>
Signed-off-by: NChris Mason <clm@fb.com>

device_list_add() is called when user runs btrfs dev scan, which would add
any btrfs device into the btrfs_fs_devices list.

Now think of a mounted btrfs. And a new device which contains the a SB
from the mounted btrfs devices.

In this situation when user runs btrfs dev scan, the current code would
just replace existing device with the new device.

Which is to note that old device is neither closed nor gracefully
removed from the btrfs.

The FS is still operational with the old bdev however the device name
is the btrfs_device is new which is provided by the btrfs dev scan.

reproducer:

devmgt[1] detach /dev/sdc

replace the missing disk /dev/sdc

btrfs rep start -f 1 /dev/sde /btrfs
Label: none  uuid: 5dc0aaf4-4683-4050-b2d6-5ebe5f5cd120
        Total devices 2 FS bytes used 32.00KiB
        devid    1 size 958.94MiB used 115.88MiB path /dev/sde
        devid    2 size 958.94MiB used 103.88MiB path /dev/sdd

make /dev/sdc to reappear

devmgt attach host2

btrfs dev scan

btrfs fi show -m
Label: none  uuid: 5dc0aaf4-4683-4050-b2d6-5ebe5f5cd120^M
        Total devices 2 FS bytes used 32.00KiB^M
        devid    1 size 958.94MiB used 115.88MiB path /dev/sdc <- Wrong.
        devid    2 size 958.94MiB used 103.88MiB path /dev/sdd

since /dev/sdc has been replaced with /dev/sde, the /dev/sdc shouldn't be
part of the btrfs-fsid when it reappears. If user want it to be part of it
then sys admin should be using btrfs device add instead.

[1] github.com/anajain/devmgt.git
Signed-off-by: NAnand Jain <anand.jain@oracle.com>
Signed-off-by: NWang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: NMiao Xie <miaox@cn.fujitsu.com>
Reviewed-by: NSatoru Takeuchi <takeuchi_satoru@jp.fujitsu.com>
Signed-off-by: NChris Mason <clm@fb.com>

For a non-existent key, btrfs_search_slot() sets path->slots[0] to the slot
where the key could have been present, which in this case would be the slot
containing the extent item which would be the next neighbor of the file range
being punched. The current code passes an incremented path->slots[0] and we
skip to the wrong file extent item. This would mean that we would fail to
merge the "yet to be created" hole with the next neighboring hole (if one
exists). Fix this.
Signed-off-by: NChandan Rajendra <chandan@linux.vnet.ibm.com>
Reviewed-by: NWang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: NChris Mason <clm@fb.com>

The caller of btrfs_submit_direct_hook() will put the original dio bio
when btrfs_submit_direct_hook() return a error number, so we needn't
put the original bio in btrfs_submit_direct_hook().
Signed-off-by: NMiao Xie <miaox@cn.fujitsu.com>
Signed-off-by: NChris Mason <clm@fb.com>

Truncates and renames are often used to replace old versions of a file
with new versions.  Applications often expect this to be an atomic
replacement, even if they haven't done anything to make sure the new
version is fully on disk.

Btrfs has strict flushing in place to make sure that renaming over an
old file with a new file will fully flush out the new file before
allowing the transaction commit with the rename to complete.

This ordering means the commit code needs to be able to lock file pages,
and there are a few paths in the filesystem where we will try to end a
transaction with the page lock held.  It's rare, but these things can
deadlock.

This patch removes the ordered flushes and switches to a best effort
filemap_flush like ext4 uses. It's not perfect, but it should fix the
deadlocks.
Signed-off-by: NChris Mason <clm@fb.com>

Under rare circumstances we can end up leaving 2 versions of a checksum
for the same file extent range.

The reason for this is that after calling btrfs_next_leaf we process
slot 0 of the leaf it returns, instead of processing the slot set in
path->slots[0]. Most of the time (by far) path->slots[0] is 0, but after
btrfs_next_leaf() releases the path and before it searches for the next
leaf, another task might cause a split of the next leaf, which migrates
some of its keys to the leaf we were processing before calling
btrfs_next_leaf(). In this case btrfs_next_leaf() returns again the
same leaf but with path->slots[0] having a slot number corresponding
to the first new key it got, that is, a slot number that didn't exist
before calling btrfs_next_leaf(), as the leaf now has more keys than
it had before. So we must really process the returned leaf starting at
path->slots[0] always, as it isn't always 0, and the key at slot 0 can
have an offset much lower than our search offset/bytenr.

For example, consider the following scenario, where we have:

sums->bytenr: 40157184, sums->len: 16384, sums end: 40173568
four 4kb file data blocks with offsets 40157184, 40161280, 40165376, 40169472

  Leaf N:

    slot = 0                           slot = btrfs_header_nritems() - 1
  |-------------------------------------------------------------------|
  | [(CSUM CSUM 39239680), size 8] ... [(CSUM CSUM 40116224), size 4] |
  |-------------------------------------------------------------------|

  Leaf N + 1:

      slot = 0                          slot = btrfs_header_nritems() - 1
  |--------------------------------------------------------------------|
  | [(CSUM CSUM 40161280), size 32] ... [((CSUM CSUM 40615936), size 8 |
  |--------------------------------------------------------------------|

Because we are at the last slot of leaf N, we call btrfs_next_leaf() to
find the next highest key, which releases the current path and then searches
for that next key. However after releasing the path and before finding that
next key, the item at slot 0 of leaf N + 1 gets moved to leaf N, due to a call
to ctree.c:push_leaf_left() (via ctree.c:split_leaf()), and therefore
btrfs_next_leaf() will returns us a path again with leaf N but with the slot
pointing to its new last key (CSUM CSUM 40161280). This new version of leaf N
is then:

    slot = 0                        slot = btrfs_header_nritems() - 2  slot = btrfs_header_nritems() - 1
  |----------------------------------------------------------------------------------------------------|
  | [(CSUM CSUM 39239680), size 8] ... [(CSUM CSUM 40116224), size 4]  [(CSUM CSUM 40161280), size 32] |
  |----------------------------------------------------------------------------------------------------|

And incorrecly using slot 0, makes us set next_offset to 39239680 and we jump
into the "insert:" label, which will set tmp to:

    tmp = min((sums->len - total_bytes) >> blocksize_bits,
        (next_offset - file_key.offset) >> blocksize_bits) =
    min((16384 - 0) >> 12, (39239680 - 40157184) >> 12) =
    min(4, (u64)-917504 = 18446744073708634112 >> 12) = 4

and

   ins_size = csum_size * tmp = 4 * 4 = 16 bytes.

In other words, we insert a new csum item in the tree with key
(CSUM_OBJECTID CSUM_KEY 40157184 = sums->bytenr) that contains the checksums
for all the data (4 blocks of 4096 bytes each = sums->len). Which is wrong,
because the item with key (CSUM CSUM 40161280) (the one that was moved from
leaf N + 1 to the end of leaf N) contains the old checksums of the last 12288
bytes of our data and won't get those old checksums removed.

So this leaves us 2 different checksums for 3 4kb blocks of data in the tree,
and breaks the logical rule:

   Key_N+1.offset >= Key_N.offset + length_of_data_its_checksums_cover

An obvious bad effect of this is that a subsequent csum tree lookup to get
the checksum of any of the blocks with logical offset of 40161280, 40165376
or 40169472 (the last 3 4kb blocks of file data), will get the old checksums.

Cc: stable@vger.kernel.org
Signed-off-by: NFilipe Manana <fdmanana@suse.com>
Signed-off-by: NChris Mason <clm@fb.com>

We've got bug reports that btrfs crashes when quota is enabled on
32bit kernel, typically with the Oops like below:
 BUG: unable to handle kernel NULL pointer dereference at 00000004
 IP: [<f9234590>] find_parent_nodes+0x360/0x1380 [btrfs]
 *pde = 00000000
 Oops: 0000 [#1] SMP
 CPU: 0 PID: 151 Comm: kworker/u8:2 Tainted: G S      W 3.15.2-1.gd43d97e-default #1
 Workqueue: btrfs-qgroup-rescan normal_work_helper [btrfs]
 task: f1478130 ti: f147c000 task.ti: f147c000
 EIP: 0060:[<f9234590>] EFLAGS: 00010213 CPU: 0
 EIP is at find_parent_nodes+0x360/0x1380 [btrfs]
 EAX: f147dda8 EBX: f147ddb0 ECX: 00000011 EDX: 00000000
 ESI: 00000000 EDI: f147dda4 EBP: f147ddf8 ESP: f147dd38
  DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068
 CR0: 8005003b CR2: 00000004 CR3: 00bf3000 CR4: 00000690
 Stack:
  00000000 00000000 f147dda4 00000050 00000001 00000000 00000001 00000050
  00000001 00000000 d3059000 00000001 00000022 000000a8 00000000 00000000
  00000000 000000a1 00000000 00000000 00000001 00000000 00000000 11800000
 Call Trace:
  [<f923564d>] __btrfs_find_all_roots+0x9d/0xf0 [btrfs]
  [<f9237bb1>] btrfs_qgroup_rescan_worker+0x401/0x760 [btrfs]
  [<f9206148>] normal_work_helper+0xc8/0x270 [btrfs]
  [<c025e38b>] process_one_work+0x11b/0x390
  [<c025eea1>] worker_thread+0x101/0x340
  [<c026432b>] kthread+0x9b/0xb0
  [<c0712a71>] ret_from_kernel_thread+0x21/0x30
  [<c0264290>] kthread_create_on_node+0x110/0x110

This indicates a NULL corruption in prefs_delayed list.  The further
investigation and bisection pointed that the call of ulist_add_merge()
results in the corruption.

ulist_add_merge() takes u64 as aux and writes a 64bit value into
old_aux.  The callers of this function in backref.c, however, pass a
pointer of a pointer to old_aux.  That is, the function overwrites
64bit value on 32bit pointer.  This caused a NULL in the adjacent
variable, in this case, prefs_delayed.

Here is a quick attempt to band-aid over this: a new function,
ulist_add_merge_ptr() is introduced to pass/store properly a pointer
value instead of u64.  There are still ugly void ** cast remaining
in the callers because void ** cannot be taken implicitly.  But, it's
safer than explicit cast to u64, anyway.

Bugzilla: https://bugzilla.novell.com/show_bug.cgi?id=887046
Cc: <stable@vger.kernel.org> [v3.11+]
Signed-off-by: NTakashi Iwai <tiwai@suse.de>
Signed-off-by: NChris Mason <clm@fb.com>

When failing to allocate space for the whole compressed extent, we'll
fallback to uncompressed IO, but we've forgotten to redirty the pages
which belong to this compressed extent, and these 'clean' pages will
simply skip 'submit' part and go to endio directly, at last we got data
corruption as we write nothing.
Signed-off-by: NLiu Bo <bo.li.liu@oracle.com>
Tested-By: NMartin Steigerwald <martin@lichtvoll.de>
Signed-off-by: NChris Mason <clm@fb.com>

ulist_add() can return '1' on sucess, which qgroup_subtree_accounting()
doesn't take into account. As a result, that value can be bubbled up to
callers, causing an error to be printed. Fix this by only returning the
value of ulist_add() when it indicates an error.
Signed-off-by: NMark Fasheh <mfasheh@suse.de>
Signed-off-by: NChris Mason <clm@fb.com>

During its tree walk, btrfs_drop_snapshot() will skip any shared
subtrees it encounters. This is incorrect when we have qgroups
turned on as those subtrees need to have their contents
accounted. In particular, the case we're concerned with is when
removing our snapshot root leaves the subtree with only one root
reference.

In those cases we need to find the last remaining root and add
each extent in the subtree to the corresponding qgroup exclusive
counts.

This patch implements the shared subtree walk and a new qgroup
operation, BTRFS_QGROUP_OPER_SUB_SUBTREE. When an operation of
this type is encountered during qgroup accounting, we search for
any root references to that extent and in the case that we find
only one reference left, we go ahead and do the math on it's
exclusive counts.
Signed-off-by: NMark Fasheh <mfasheh@suse.de>
Reviewed-by: NJosef Bacik <jbacik@fb.com>
Signed-off-by: NChris Mason <clm@fb.com>

Before processing the extent buffer, acquire a read lock on it, so
that we're safe against concurrent updates on the extent buffer.
Signed-off-by: NFilipe Manana <fdmanana@suse.com>
Signed-off-by: NChris Mason <clm@fb.com>

Before I extended the no_quota arg to btrfs_dec/inc_ref because I didn't
understand how snapshot delete was using it and assumed that we needed the
quota operations there.  With Mark's work this has turned out to be not the
case, we _always_ need to use no_quota for btrfs_dec/inc_ref, so just drop the
argument and make __btrfs_mod_ref call it's process function with no_quota set
always.  Thanks,
Signed-off-by: NJosef Bacik <jbacik@fb.com>
Signed-off-by: NChris Mason <clm@fb.com>

This has been discussed in thread:
http://thread.gmane.org/gmane.comp.file-systems.btrfs/32528

and this patch implements this proposal:
http://thread.gmane.org/gmane.comp.file-systems.btrfs/32536

Works fine for "clean" raid profiles where the raid factor correction
does the right job. Otherwise it's pessimistic and may show low space
although there's still some left.

The df nubmers are lightly wrong in case of mixed block groups, but this
is not a major usecase and can be addressed later.

The RAID56 numbers are wrong almost the same way as before and will be
addressed separately.

CC: Hugo Mills <hugo@carfax.org.uk>
CC: cwillu <cwillu@cwillu.com>
CC: Josef Bacik <jbacik@fb.com>
Signed-off-by: NDavid Sterba <dsterba@suse.cz>
Signed-off-by: NChris Mason <clm@fb.com>

commit 99994cde btrfs: dev delete should remove sysfs entry
added a btrfs_kobj_rm_device, which dereferences device->bdev...
right after we check whether device->bdev might be NULL.

I don't honestly know if it's possible to have a NULL device->bdev
here, but assuming that it is (given the test), we need to move
the kobject removal to be under that test.

(Coverity spotted this)
Signed-off-by: NEric Sandeen <sandeen@redhat.com>
Signed-off-by: NChris Mason <clm@fb.com>

xfstests generic/127 detected this problem.

With commit 7fc34a62, now fsync will only flush
data within the passed range.  This is the cause of the above problem,
-- btrfs's fsync has a stage called 'sync log' which will wait for all the
ordered extents it've recorded to finish.

In xfstests/generic/127, with mixed operations such as truncate, fallocate,
punch hole, and mapwrite, we get some pre-allocated extents, and mapwrite will
mmap, and then msync.  And I find that msync will wait for quite a long time
(about 20s in my case), thanks to ftrace, it turns out that the previous
fallocate calls 'btrfs_wait_ordered_range()' to flush dirty pages, but as the
range of dirty pages may be larger than 'btrfs_wait_ordered_range()' wants,
there can be some ordered extents created but not getting corresponding pages
flushed, then they're left in memory until we fsync which runs into the
stage 'sync log', and fsync will just wait for the system writeback thread
to flush those pages and get ordered extents finished, so the latency is
inevitable.

This adds a flush similar to btrfs_start_ordered_extent() in
btrfs_wait_logged_extents() to fix that.
Reviewed-by: NMiao Xie <miaox@cn.fujitsu.com>
Signed-off-by: NLiu Bo <bo.li.liu@oracle.com>
Signed-off-by: NChris Mason <clm@fb.com>

Often when starting a transaction we commit the currently running transaction,
which can end up writing block group caches when the current process has its
journal_info set to NULL (and not to a transaction). This makes our assertion
at btrfs_check_data_free_space() (current_journal != NULL) fail, resulting
in a crash/hang. Therefore fix it by setting journal_info.

Two different traces of this issue follow below.

1)

    [51502.241936] BTRFS: assertion failed: current->journal_info, file: fs/btrfs/extent-tree.c, line: 3670
    [51502.242213] ------------[ cut here ]------------
    [51502.242493] kernel BUG at fs/btrfs/ctree.h:3964!
    [51502.242669] invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC
    (...)
    [51502.244010] Call Trace:
    [51502.244010]  [<ffffffffa02bc025>] btrfs_check_data_free_space+0x395/0x3a0 [btrfs]
    [51502.244010]  [<ffffffffa02c3bdc>] btrfs_write_dirty_block_groups+0x4ac/0x640 [btrfs]
    [51502.244010]  [<ffffffffa0357a6a>] commit_cowonly_roots+0x164/0x226 [btrfs]
    [51502.244010]  [<ffffffffa02d53cd>] btrfs_commit_transaction+0x4ed/0xab0 [btrfs]
    [51502.244010]  [<ffffffff8168ec7b>] ? _raw_spin_unlock+0x2b/0x40
    [51502.244010]  [<ffffffffa02d6259>] start_transaction+0x459/0x620 [btrfs]
    [51502.244010]  [<ffffffffa02d67ab>] btrfs_start_transaction+0x1b/0x20 [btrfs]
    [51502.244010]  [<ffffffffa02d73e1>] __unlink_start_trans+0x31/0xe0 [btrfs]
    [51502.244010]  [<ffffffffa02dea67>] btrfs_unlink+0x37/0xc0 [btrfs]
    [51502.244010]  [<ffffffff811bb054>] ? do_unlinkat+0x114/0x2a0
    [51502.244010]  [<ffffffff811baebc>] vfs_unlink+0xcc/0x150
    [51502.244010]  [<ffffffff811bb1a0>] do_unlinkat+0x260/0x2a0
    [51502.244010]  [<ffffffff811a9ef4>] ? filp_close+0x64/0x90
    [51502.244010]  [<ffffffff810aaea6>] ? trace_hardirqs_on_caller+0x16/0x1e0
    [51502.244010]  [<ffffffff81349cab>] ? trace_hardirqs_on_thunk+0x3a/0x3f
    [51502.244010]  [<ffffffff811be9eb>] SyS_unlinkat+0x1b/0x40
    [51502.244010]  [<ffffffff81698452>] system_call_fastpath+0x16/0x1b
    [51502.244010] Code: 0b 55 48 89 e5 0f 0b 55 48 89 e5 0f 0b 55 89 f1 48 c7 c2 71 13 36 a0 48 89 fe 31 c0 48 c7 c7 b8 43 36 a0 48 89 e5 e8 5d b0 32 e1 <0f> 0b 0f 1f 44 00 00 55 b9 11 00 00 00 48 89 e5 41 55 49 89 f5
    [51502.244010] RIP  [<ffffffffa03575da>] assfail.constprop.88+0x1e/0x20 [btrfs]

2)

    [25405.097230] BTRFS: assertion failed: current->journal_info, file: fs/btrfs/extent-tree.c, line: 3670
    [25405.097488] ------------[ cut here ]------------
    [25405.097767] kernel BUG at fs/btrfs/ctree.h:3964!
    [25405.097940] invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC
    (...)
    [25405.100008] Call Trace:
    [25405.100008]  [<ffffffffa02bc025>] btrfs_check_data_free_space+0x395/0x3a0 [btrfs]
    [25405.100008]  [<ffffffffa02c3bdc>] btrfs_write_dirty_block_groups+0x4ac/0x640 [btrfs]
    [25405.100008]  [<ffffffffa035755a>] commit_cowonly_roots+0x164/0x226 [btrfs]
    [25405.100008]  [<ffffffffa02d53cd>] btrfs_commit_transaction+0x4ed/0xab0 [btrfs]
    [25405.100008]  [<ffffffff8109c170>] ? bit_waitqueue+0xc0/0xc0
    [25405.100008]  [<ffffffffa02d6259>] start_transaction+0x459/0x620 [btrfs]
    [25405.100008]  [<ffffffffa02d67ab>] btrfs_start_transaction+0x1b/0x20 [btrfs]
    [25405.100008]  [<ffffffffa02e3407>] btrfs_create+0x47/0x210 [btrfs]
    [25405.100008]  [<ffffffffa02d74cc>] ? btrfs_permission+0x3c/0x80 [btrfs]
    [25405.100008]  [<ffffffff811bc63b>] vfs_create+0x9b/0x130
    [25405.100008]  [<ffffffff811bcf19>] do_last+0x849/0xe20
    [25405.100008]  [<ffffffff811b9409>] ? link_path_walk+0x79/0x820
    [25405.100008]  [<ffffffff811bd5b5>] path_openat+0xc5/0x690
    [25405.100008]  [<ffffffff810ab07d>] ? trace_hardirqs_on+0xd/0x10
    [25405.100008]  [<ffffffff811cdcd2>] ? __alloc_fd+0x32/0x1d0
    [25405.100008]  [<ffffffff811be2a3>] do_filp_open+0x43/0xa0
    [25405.100008]  [<ffffffff811cddf1>] ? __alloc_fd+0x151/0x1d0
    [25405.100008]  [<ffffffff811abcfc>] do_sys_open+0x13c/0x230
    [25405.100008]  [<ffffffff810aaea6>] ? trace_hardirqs_on_caller+0x16/0x1e0
    [25405.100008]  [<ffffffff811abe12>] SyS_open+0x22/0x30
    [25405.100008]  [<ffffffff81698452>] system_call_fastpath+0x16/0x1b
    [25405.100008] Code: 0b 55 48 89 e5 0f 0b 55 48 89 e5 0f 0b 55 89 f1 48 c7 c2 51 13 36 a0 48 89 fe 31 c0 48 c7 c7 d0 43 36 a0 48 89 e5 e8 6d b5 32 e1 <0f> 0b 0f 1f 44 00 00 55 b9 11 00 00 00 48 89 e5 41 55 49 89 f5
    [25405.100008] RIP  [<ffffffffa03570ca>] assfail.constprop.88+0x1e/0x20 [btrfs]
Signed-off-by: NFilipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: NChris Mason <clm@fb.com>

We wouldn't actuall print the extent information if we had a skinny metadata
item, this fixes that.  Thanks,
Signed-off-by: NJosef Bacik <jbacik@fb.com>
Signed-off-by: NChris Mason <clm@fb.com>

This percpu counter @total_bytes_pinned is introduced to skip unnecessary
operations of 'commit transaction', it accounts for those space we may free
but are stuck in delayed refs.

And we zero out @space_info->total_bytes_pinned every transaction period so
we have a better idea of how much space we'll actually free up by committing
this transaction.  However, we do the 'zero out' part a little earlier, before
we actually unpin space, so we end up returning ENOSPC when we actually have
free space that's just unpinned from committing transaction.

xfstests/generic/074 complained then.

This fixes it by actually accounting the percpu pinned number when 'unpin',
and since it's protected by space_info->lock, the race is gone now.
Signed-off-by: NLiu Bo <bo.li.liu@oracle.com>
Reviewed-by: NMiao Xie <miaox@cn.fujitsu.com>
Signed-off-by: NChris Mason <clm@fb.com>

Return codes got updated in 60e1975a
(btrfs: return errno instead of -1 from compression)
lzo wrapper returns E2BIG in this case, do the same for zlib.
Signed-off-by: NDavid Sterba <dsterba@suse.cz>

Commit fcebe456 (Btrfs: rework qgroup
accounting) removed the qgroup accounting after delayed refs.
Signed-off-by: NDavid Sterba <dsterba@suse.cz>

The transaction handle was being used after being freed.

Cc: Chris Mason <clm@fb.com>
Signed-off-by: NFilipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: NChris Mason <clm@fb.com>

dev->name is null but missing flag is not set.
Strictly speaking the missing flag should have been set, but there
are more places where code just checks if name is null. For now this
patch does the same.

stack:
BUG: unable to handle kernel NULL pointer dereference at 0000000000000064
IP: [<ffffffffa0228908>] btrfs_show_devname+0x58/0xf0 [btrfs]

[<ffffffff81198879>] show_vfsmnt+0x39/0x130
[<ffffffff81178056>] m_show+0x16/0x20
[<ffffffff8117d706>] seq_read+0x296/0x390
[<ffffffff8115aa7d>] vfs_read+0x9d/0x160
[<ffffffff8115b549>] SyS_read+0x49/0x90
[<ffffffff817abe52>] system_call_fastpath+0x16/0x1b

reproducer:
mkfs.btrfs -draid1 -mraid1 /dev/sdg1 /dev/sdg2
btrfstune -S 1 /dev/sdg1
modprobe -r btrfs && modprobe btrfs
mount -o degraded /dev/sdg1 /btrfs
btrfs dev add /dev/sdg3 /btrfs
Signed-off-by: NAnand Jain <Anand.Jain@oracle.com>
Signed-off-by: NChris Mason <clm@fb.com>

when one of the device path is missing btrfs_device name is null. So this
patch will check for that.

stack:
BUG: unable to handle kernel NULL pointer dereference at 0000000000000010
IP: [<ffffffff812e18c0>] strlen+0x0/0x30
[<ffffffffa01cd92a>] ? clone_fs_devices+0xaa/0x160 [btrfs]
[<ffffffffa01cdcf7>] btrfs_init_new_device+0x317/0xca0 [btrfs]
[<ffffffff81155bca>] ? __kmalloc_track_caller+0x15a/0x1a0
[<ffffffffa01d6473>] btrfs_ioctl+0xaa3/0x2860 [btrfs]
[<ffffffff81132a6c>] ? handle_mm_fault+0x48c/0x9c0
[<ffffffff81192a61>] ? __blkdev_put+0x171/0x180
[<ffffffff817a784c>] ? __do_page_fault+0x4ac/0x590
[<ffffffff81193426>] ? blkdev_put+0x106/0x110
[<ffffffff81179175>] ? mntput+0x35/0x40
[<ffffffff8116d4b0>] do_vfs_ioctl+0x460/0x4a0
[<ffffffff8115c72e>] ? ____fput+0xe/0x10
[<ffffffff81068033>] ? task_work_run+0xb3/0xd0
[<ffffffff8116d547>] SyS_ioctl+0x57/0x90
[<ffffffff817a793e>] ? do_page_fault+0xe/0x10
[<ffffffff817abe52>] system_call_fastpath+0x16/0x1b

reproducer:
mkfs.btrfs -draid1 -mraid1 /dev/sdg1 /dev/sdg2
btrfstune -S 1 /dev/sdg1
modprobe -r btrfs && modprobe btrfs
mount -o degraded /dev/sdg1 /btrfs
btrfs dev add /dev/sdg3 /btrfs
Signed-off-by: NAnand Jain <Anand.Jain@oracle.com>
Signed-off-by: NChris Mason <clm@fb.com>

The commit

07802534 btrfs: Cleanup the btrfs_parse_options for remount.

broke ssd options quite badly; it stopped making ssd_spread
imply ssd, and it made "nossd" unsettable.

Put things back at least as well as they were before
(though ssd mount option handling is still pretty odd:
# mount -o "nossd,ssd_spread" works?)
Reported-by: NRoman Mamedov <rm@romanrm.net>
Signed-off-by: NEric Sandeen <sandeen@redhat.com>
Signed-off-by: NChris Mason <clm@fb.com>

Balance recovery is called when RW mounting or remounting from
RO to RW, it is called to finish roots merging.

When doing balance recovery, relocation root's corresponding
fs root(whose root refs is 0) might be destroyed by cleaner
thread, this will make btrfs fail to mount.

Fix this problem by holding @cleaner_mutex when doing balance
recovery.
Signed-off-by: NWang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: NChris Mason <clm@fb.com>

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: NDavid Sterba <dsterba@suse.cz>
Reviewed-by: NSatoru Takeuchi <takeuchi_satoru@jp.fujitsu.com>
Signed-off-by: NFilipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: NChris Mason <clm@fb.com>

This is a regression from my patch a26e8c9f, we
need to only unlock the block if we were the one who locked it.  Otherwise this
will trip BUG_ON()'s in locking.c  Thanks,

cc: stable@vger.kernel.org
Signed-off-by: NJosef Bacik <jbacik@fb.com>
Signed-off-by: NChris Mason <clm@fb.com>

When starting a transaction just assert that current->journal_info
doesn't contain a send transaction stub, since send isn't supposed
to start transactions and when it finishes (either successfully or
not) it's supposed to set current->journal_info to NULL.

This is motivated by the change titled:

    Btrfs: fix crash when starting transaction
Signed-off-by: NFilipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: NChris Mason <clm@fb.com>

Add compression `workspace' in free_workspace() to
`idle_workspace' list head, instead of tail. So we have
better chances to reuse most recently used `workspace'.
Signed-off-by: NSergey Senozhatsky <sergey.senozhatsky@gmail.com>
Reviewed-by: NDavid Sterba <dsterba@suse.cz>
Signed-off-by: NChris Mason <clm@fb.com>

The reproducer is

$ mkfs.btrfs D1 D2 D3 -mraid5
$ mkfs.ext4 D2 && mkfs.ext4 D3
$ mount D1 /btrfs -odegraded

-------------------

[   87.672992] ------------[ cut here ]------------
[   87.673845] kernel BUG at fs/btrfs/raid56.c:1828!
...
[   87.673845] RIP: 0010:[<ffffffff813efc7e>]  [<ffffffff813efc7e>] __raid_recover_end_io+0x4ae/0x4d0
...
[   87.673845] Call Trace:
[   87.673845]  [<ffffffff8116bbc6>] ? mempool_free+0x36/0xa0
[   87.673845]  [<ffffffff813f0255>] raid_recover_end_io+0x75/0xa0
[   87.673845]  [<ffffffff81447c5b>] bio_endio+0x5b/0xa0
[   87.673845]  [<ffffffff81447cb2>] bio_endio_nodec+0x12/0x20
[   87.673845]  [<ffffffff81374621>] end_workqueue_fn+0x41/0x50
[   87.673845]  [<ffffffff813ad2aa>] normal_work_helper+0xca/0x2c0
[   87.673845]  [<ffffffff8108ba2b>] process_one_work+0x1eb/0x530
[   87.673845]  [<ffffffff8108b9c9>] ? process_one_work+0x189/0x530
[   87.673845]  [<ffffffff8108c15b>] worker_thread+0x11b/0x4f0
[   87.673845]  [<ffffffff8108c040>] ? rescuer_thread+0x290/0x290
[   87.673845]  [<ffffffff810939c4>] kthread+0xe4/0x100
[   87.673845]  [<ffffffff810938e0>] ? kthread_create_on_node+0x220/0x220
[   87.673845]  [<ffffffff817e7c7c>] ret_from_fork+0x7c/0xb0
[   87.673845]  [<ffffffff810938e0>] ? kthread_create_on_node+0x220/0x220

-------------------

It's because that we miscalculate @rbio->bbio->error so that it doesn't
reach maximum of tolerable errors while it should have.
Signed-off-by: NLiu Bo <bo.li.liu@oracle.com>
Tested-by: Satoru Takeuchi<takeuchi_satoru@jp.fujitsu.com>
Signed-off-by: NChris Mason <clm@fb.com>

Creating sprout will change the fsid of the mounted root.
do the same on the sysfs as well.

reproducer:
 mount /dev/sdb /btrfs (seed disk)
 btrfs dev add /dev/sdc /btrfs
 mount -o rw,remount /btrfs
 btrfs dev del /dev/sdb /btrfs
 mount /dev/sdb /btrfs

Error:
kobject_add_internal failed for fe350492-dc28-4051-a601-e017b17e6145 with -EEXIST, don't try to register things with the same name in the same directory.
Signed-off-by: NAnand Jain <anand.jain@oracle.com>
Reviewed-by: NDavid Sterba <dsterba@suse.cz>
Signed-off-by: NChris Mason <clm@fb.com>

when we replace the device its corresponding sysfs
entry has to be replaced as well
Signed-off-by: NAnand Jain <anand.jain@oracle.com>
Reviewed-by: NDavid Sterba <dsterba@suse.cz>
Signed-off-by: NChris Mason <clm@fb.com>

we would need the device links to be created,
when device is added.
Signed-off-by: NAnand Jain <Anand.Jain@oracle.com>
Reviewed-by: NDavid Sterba <dsterba@suse.cz>
Signed-off-by: NChris Mason <clm@fb.com>

when we delete the device from the mounted btrfs,
we would need its corresponding sysfs enty to
be removed as well.
Signed-off-by: NAnand Jain <Anand.Jain@oracle.com>
Reviewed-by: NDavid Sterba <dsterba@suse.cz>
Signed-off-by: NChris Mason <clm@fb.com>

Signed-off-by: NAnand Jain <anand.jain@oracle.com>
Reviewed-by: NDavid Sterba <dsterba@suse.cz>
Signed-off-by: NChris Mason <clm@fb.com>