Commit Graph

49368 Commits

Author SHA1 Message Date
Omar Sandoval 0d9f824df3 Btrfs: make add_pinned_bytes() take an s64 num_bytes instead of u64
There are a few places where we pass in a negative num_bytes, so make it
signed for clarity. Also move it up in the file since later patches will
need it there.

Signed-off-by: Omar Sandoval <osandov@fb.com>
Tested-by: Holger Hoffstätte <holger@applied-asynchrony.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-29 20:17:01 +02:00
David Sterba 1164a9fb9c btrfs: fix validation of XATTR_ITEM dir items
The XATTR_ITEM is a type of a directory item so we use the common
validator helper. Unlike other dir items, it can have data. The way the
name len validation is currently implemented does not reflect that. We'd
have to adjust by the data_len when comparing the read and item limits.

However, this will not work for multi-item xattr dir items.

Example from tree dump of generic/337:

        item 7 key (257 XATTR_ITEM 751495445) itemoff 15667 itemsize 147
                location key (0 UNKNOWN.0 0) type XATTR
                transid 8 data_len 3 name_len 11
                name: user.foobar
                data 123
                location key (0 UNKNOWN.0 0) type XATTR
                transid 8 data_len 6 name_len 13
                name: user.WvG1c1Td
                data qwerty
                location key (0 UNKNOWN.0 0) type XATTR
                transid 8 data_len 5 name_len 19
                name: user.J3__T_Km3dVsW_
                data hello

At the point of btrfs_is_name_len_valid call we don't have access to the
data_len value of the 2nd and 3rd sub-item. So simple btrfs_dir_data_len(leaf,
di) would always return 3, although we'd need to get 6 and 5 respectively to
get the claculations right. (read_end + name_len + data_len vs item_end)

We'd have to also pass data_len externally, which is not point of the
name validation. The last check is supposed to test if there's at least
one dir item space after the one we're processing. I don't think this is
particularly useful, validation of the next item would catch that too.
So the check is removed and we don't weaken the validation. Now tests
btrfs/048, btrfs/053, generic/273 and generic/337 pass.

Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-29 20:06:11 +02:00
Su Yue fbc326159a btrfs: Verify dir_item in iterate_object_props
Call verify_dir_item before memcmp_extent_buffer reading name from
dir_item.

Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-21 19:16:04 +02:00
Su Yue 64c7b01446 btrfs: Check name_len before in btrfs_del_root_ref
btrfs_del_root_ref calls btrfs_search_slot and reads name from root_ref.
Call btrfs_is_name_len_valid before memcmp.

Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-21 19:16:04 +02:00
Su Yue 488d7c4566 btrfs: Check name_len before reading btrfs_get_name
In btrfs_get_name, there's btrfs_search_slot and reads name from
inode_ref/root_ref.

Call btrfs_is_name_len_valid in btrfs_get_name.

Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-21 19:16:04 +02:00
Su Yue 59b0a7f2c7 btrfs: Check name_len before read in iterate_dir_item
Since iterate_dir_item checks name_len in its own way,
so use btrfs_is_name_len_valid not 'verify_dir_item' to make more strict
name_len check.

Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ switched ENAMETOOLONG to EIO ]
Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-21 19:16:04 +02:00
Su Yue 3c1d418448 btrfs: Check name_len in btrfs_check_ref_name_override
In btrfs_log_inode, btrfs_search_forward gets the buffer and then
btrfs_check_ref_name_override will read name from ref/extref for the
first time.

Call btrfs_is_name_len_valid before reading name.

Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-21 19:16:04 +02:00
Su Yue 8ee8c2d62d btrfs: Verify dir_item in replay_xattr_deletes
replay_xattr_deletes calls btrfs_search_slot to get buffer and reads
name.

Call verify_dir_item to check name_len in replay_xattr_deletes to avoid
reading out of boundary.

Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-21 19:16:04 +02:00
Su Yue 26a836cec2 btrfs: Check name_len on add_inode_ref call path
replay_one_buffer first reads buffers and dispatches items accroding to
the item type.
In this patch, add_inode_ref handles inode_ref and inode_extref.
Then add_inode_ref calls ref_get_fields and extref_get_fields to read
ref/extref name for the first time.
So checking name_len before reading those two is fine.

add_inode_ref also calls inode_in_dir to match ref/extref in parent_dir.
The call graph includes btrfs_match_dir_item_name to read dir_item name
in the parent dir.
Checking first dir_item is not enough. Change it to verify every
dir_item while doing matches.

Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-21 19:16:04 +02:00
Su Yue e79a33270d btrfs: Check name_len with boundary in verify dir_item
Originally, verify_dir_item verifies name_len of dir_item with fixed
values but not item boundary.
If corrupted name_len was not bigger than the fixed value, for example
255, the function will think the dir_item is fine. And then reading
beyond boundary will cause crash.

Example:
	1. Corrupt one dir_item name_len to be 255.
        2. Run 'ls -lar /mnt/test/ > /dev/null'
dmesg:
[   48.451449] BTRFS info (device vdb1): disk space caching is enabled
[   48.451453] BTRFS info (device vdb1): has skinny extents
[   48.489420] general protection fault: 0000 [#1] SMP
[   48.489571] Modules linked in: ext4 jbd2 mbcache btrfs xor raid6_pq
[   48.489716] CPU: 1 PID: 2710 Comm: ls Not tainted 4.10.0-rc1 #5
[   48.489853] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.10.2-20170228_101828-anatol 04/01/2014
[   48.490008] task: ffff880035df1bc0 task.stack: ffffc90004800000
[   48.490008] RIP: 0010:read_extent_buffer+0xd2/0x190 [btrfs]
[   48.490008] RSP: 0018:ffffc90004803d98 EFLAGS: 00010202
[   48.490008] RAX: 000000000000001b RBX: 000000000000001b RCX: 0000000000000000
[   48.490008] RDX: ffff880079dbf36c RSI: 0005080000000000 RDI: ffff880079dbf368
[   48.490008] RBP: ffffc90004803dc8 R08: ffff880078e8cc48 R09: ffff880000000000
[   48.490008] R10: 0000160000000000 R11: 0000000000001000 R12: ffff880079dbf288
[   48.490008] R13: ffff880078e8ca88 R14: 0000000000000003 R15: ffffc90004803e20
[   48.490008] FS:  00007fef50c60800(0000) GS:ffff88007d400000(0000) knlGS:0000000000000000
[   48.490008] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   48.490008] CR2: 000055f335ac2ff8 CR3: 000000007356d000 CR4: 00000000001406e0
[   48.490008] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   48.490008] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   48.490008] Call Trace:
[   48.490008]  btrfs_real_readdir+0x3b7/0x4a0 [btrfs]
[   48.490008]  iterate_dir+0x181/0x1b0
[   48.490008]  SyS_getdents+0xa7/0x150
[   48.490008]  ? fillonedir+0x150/0x150
[   48.490008]  entry_SYSCALL_64_fastpath+0x18/0xad
[   48.490008] RIP: 0033:0x7fef5032546b
[   48.490008] RSP: 002b:00007ffeafcdb830 EFLAGS: 00000206 ORIG_RAX: 000000000000004e
[   48.490008] RAX: ffffffffffffffda RBX: 00007fef5061db38 RCX: 00007fef5032546b
[   48.490008] RDX: 0000000000008000 RSI: 000055f335abaff0 RDI: 0000000000000003
[   48.490008] RBP: 00007fef5061dae0 R08: 00007fef5061db48 R09: 0000000000000000
[   48.490008] R10: 000055f335abafc0 R11: 0000000000000206 R12: 00007fef5061db38
[   48.490008] R13: 0000000000008040 R14: 00007fef5061db38 R15: 000000000000270e
[   48.490008] RIP: read_extent_buffer+0xd2/0x190 [btrfs] RSP: ffffc90004803d98
[   48.499455] ---[ end trace 321920d8e8339505 ]---

Fix it by adding a parameter @slot and check name_len with item boundary
by calling btrfs_is_name_len_valid.

Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
rev
Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-21 19:16:04 +02:00
Su Yue 19c6dcbfa7 btrfs: Introduce btrfs_is_name_len_valid to avoid reading beyond boundary
Introduce function btrfs_is_name_len_valid.

The function compares parameter @name_len with item boundary then
returns true if name_len is valid.

Signed-off-by: Su Yue <suy.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ s/btrfs_leaf_data/BTRFS_LEAF_DATA_OFFSET/ ]
Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-21 19:16:04 +02:00
David Sterba 66b4993e95 btrfs: move dev stats accounting out of wait_dev_flush
We should really just wait in wait_dev_flush and let the caller decide
what to do with the error value.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-21 19:03:39 +02:00
David Sterba 2980d5745f btrfs: account as waiting for IO, while waiting fot the flush bio completion
Similar to what submit_bio_wait does, we should account for IO while
waiting for a bio completion. This has marginal visible effects, flush
bio is short-lived.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-21 19:03:39 +02:00
David Sterba e0ae999414 btrfs: preallocate device flush bio
For devices that support flushing, we allocate a bio, submit, wait for
it and then free it. The bio allocation does not fail so ENOMEM is not a
problem but we still may unnecessarily stress the allocation subsystem.

Instead, we can allocate the bio at the same time we allocate the device
and reuse it each time we need to flush the barriers. The bio is reset
before each use. Reference counting is simplified to just device
allocation (get) and freeing (put).

The bio used to be submitted through the integrity checker which will
find out that bio has no data attached and call submit_bio.

Status of the bio in flight needs to be tracked separately in case the
device caches get switched off between write and wait.

Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-21 19:03:38 +02:00
Filipe Manana fdb1388994 Btrfs: incremental send, fix invalid path for unlink commands
An incremental send can contain unlink operations with an invalid target
path when we rename some directory inode A, then rename some file inode B
to the old name of inode A and directory inode A is an ancestor of inode B
in the parent snapshot (but not anymore in the send snapshot).

Consider the following example scenario where this issue happens.

Parent snapshot:

 .                                                      (ino 256)
 |
 |--- dir1/                                             (ino 257)
       |--- dir2/                                       (ino 258)
       |     |--- file1                                 (ino 259)
       |     |--- file3                                 (ino 261)
       |
       |--- dir3/                                       (ino 262)
             |--- file22                                (ino 260)
             |--- dir4/                                 (ino 263)

Send snapshot:

 .                                                      (ino 256)
 |
 |--- dir1/                                             (ino 257)
       |--- dir2/                                       (ino 258)
       |--- dir3                                        (ino 260)
       |--- file3/                                      (ino 262)
             |--- dir4/                                 (ino 263)
                   |--- file11                          (ino 269)
                   |--- file33                          (ino 261)

When attempting to apply the corresponding incremental send stream, an
unlink operation contains an invalid path which makes the receiver fail.
The following is verbose output of the btrfs receive command:

 receiving snapshot snap2 uuid=7d5450da-a573-e043-a451-ec85f4879f0f (...)
 utimes
 utimes dir1
 utimes dir1/dir2
 link dir1/dir3/dir4/file11 -> dir1/dir2/file1
 unlink dir1/dir2/file1
 utimes dir1/dir2
 truncate dir1/dir3/dir4/file11 size=0
 utimes dir1/dir3/dir4/file11
 rename dir1/dir3 -> o262-7-0
 link dir1/dir3 -> o262-7-0/file22
 unlink dir1/dir3/file22
 ERROR: unlink dir1/dir3/file22 failed. Not a directory

The following steps happen during the computation of the incremental send
stream the lead to this issue:

1) Before we start processing the new and deleted references for inode
   260, we compute the full path of the deleted reference
   ("dir1/dir3/file22") and cache it in the list of deleted references
   for our inode.

2) We then start processing the new references for inode 260, for which
   there is only one new, located at "dir1/dir3". When processing this
   new reference, we check that inode 262, which was not yet processed,
   collides with the new reference and because of that we orphanize
   inode 262 so its new full path becomes "o262-7-0".

3) After the orphanization of inode 262, we create the new reference for
   inode 260 by issuing a link command with a target path of "dir1/dir3"
   and a source path of "o262-7-0/file22".

4) We then start processing the deleted references for inode 260, for
   which there is only one with the base name of "file22", and issue
   an unlink operation containing the target path computed at step 1,
   which is wrong because that path no longer exists and should be
   replaced with "o262-7-0/file22".

So fix this issue by recomputing the full path of deleted references if
when we processed the new references for an inode we ended up orphanizing
any other inode that is an ancestor of our inode in the parent snapshot.

A test case for fstests follows soon.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
[ adjusted after prev patch removed fs_path::dir_path and dir_path_len ]
Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-21 16:53:10 +02:00
Filipe Manana 72c3668fed Btrfs: send, fix invalid path after renaming and linking file
Currently an incremental snapshot can generate link operations which
contain an invalid target path. Such case happens when in the send
snapshot a file was renamed, a new hard link added for it and some
other inode (with a lower number) got renamed to the former name of
that file. Example:

Parent snapshot

 .                  (ino 256)
 |
 |--- f1            (ino 257)
 |--- f2            (ino 258)
 |--- f3            (ino 259)

Send snapshot

 .                  (ino 256)
 |
 |--- f2            (ino 257)
 |--- f3            (ino 258)
 |--- f4            (ino 259)
 |--- f5            (ino 258)

The following steps happen when computing the incremental send stream:

1) When processing inode 257, inode 258 is orphanized (renamed to
   "o258-7-0"), because its current reference has the same name as the
   new reference for inode 257;

2) When processing inode 258, we iterate over all its new references,
   which have the names "f3" and "f5". The first iteration sees name
   "f5" and renames the inode from its orphan name ("o258-7-0") to
   "f5", while the second iteration sees the name "f3" and, incorrectly,
   issues a link operation with a target name matching the orphan name,
   which no longer exists. The first iteration had reset the current
   valid path of the inode to "f5", but in the second iteration we lost
   it because we found another inode, with a higher number of 259, which
   has a reference named "f3" as well, so we orphanized inode 259 and
   recomputed the current valid path of inode 258 to its old orphan
   name because inode 259 could be an ancestor of inode 258 and therefore
   the current valid path could contain the pre-orphanization name of
   inode 259. However in this case inode 259 is not an ancestor of inode
   258 so the current valid path should not be recomputed.
   This makes the receiver fail with the following error:

   ERROR: link f3 -> o258-7-0 failed: No such file or directory

So fix this by not recomputing the current valid path for an inode
whenever we find a colliding reference from some not yet processed inode
(inode number higher then the one currently being processed), unless
that other inode is an ancestor of the one we are currently processing.

A test case for fstests will follow soon.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-21 16:53:03 +02:00
Filipe Manana 609805d809 Btrfs: fix invalid extent maps due to hole punching
While punching a hole in a range that is not aligned with the sector size
(currently the same as the page size) we can end up leaving an extent map
in memory with a length that is smaller then the sector size or with a
start offset that is not aligned to the sector size. Both cases are not
expected and can lead to problems. This issue is easily detected
after the patch from commit a7e3b975a0 ("Btrfs: fix reported number of
inode blocks"), introduced in kernel 4.12-rc1, in a scenario like the
following for example:

  $ mkfs.btrfs -f /dev/sdb
  $ mount /dev/sdb /mnt
  $ xfs_io -c "pwrite -S 0xaa -b 100K 0 100K" /mnt/foo
  $ xfs_io -c "fpunch 60K 90K" /mnt/foo
  $ xfs_io -c "pwrite -S 0xbb -b 100K 50K 100K" /mnt/foo
  $ xfs_io -c "pwrite -S 0xcc -b 50K 100K 50K" /mnt/foo
  $ umount /mnt

After the unmount operation we can see several warnings emmitted due to
underflows related to space reservation counters:

[ 2837.443299] ------------[ cut here ]------------
[ 2837.447395] WARNING: CPU: 8 PID: 2474 at fs/btrfs/inode.c:9444 btrfs_destroy_inode+0xe8/0x27e [btrfs]
[ 2837.452108] Modules linked in: dm_flakey dm_mod ppdev parport_pc psmouse parport sg pcspkr acpi_cpufreq tpm_tis tpm_tis_core i2c_piix4 i2c_core evdev tpm button se
rio_raw sunrpc loop autofs4 ext4 crc16 jbd2 mbcache btrfs raid10 raid456 async_raid6_recov async_memcpy async_pq async_xor async_tx xor raid6_pq libcrc32c crc32c_gene
ric raid1 raid0 multipath linear md_mod sr_mod cdrom sd_mod ata_generic virtio_scsi ata_piix libata virtio_pci virtio_ring virtio e1000 scsi_mod floppy
[ 2837.458389] CPU: 8 PID: 2474 Comm: umount Tainted: G        W       4.10.0-rc8-btrfs-next-43+ #1
[ 2837.459754] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.9.1-0-gb3ef39f-prebuilt.qemu-project.org 04/01/2014
[ 2837.462379] Call Trace:
[ 2837.462379]  dump_stack+0x68/0x92
[ 2837.462379]  __warn+0xc2/0xdd
[ 2837.462379]  warn_slowpath_null+0x1d/0x1f
[ 2837.462379]  btrfs_destroy_inode+0xe8/0x27e [btrfs]
[ 2837.462379]  destroy_inode+0x3d/0x55
[ 2837.462379]  evict+0x177/0x17e
[ 2837.462379]  dispose_list+0x50/0x71
[ 2837.462379]  evict_inodes+0x132/0x141
[ 2837.462379]  generic_shutdown_super+0x3f/0xeb
[ 2837.462379]  kill_anon_super+0x12/0x1c
[ 2837.462379]  btrfs_kill_super+0x16/0x21 [btrfs]
[ 2837.462379]  deactivate_locked_super+0x30/0x68
[ 2837.462379]  deactivate_super+0x36/0x39
[ 2837.462379]  cleanup_mnt+0x58/0x76
[ 2837.462379]  __cleanup_mnt+0x12/0x14
[ 2837.462379]  task_work_run+0x77/0x9b
[ 2837.462379]  prepare_exit_to_usermode+0x9d/0xc5
[ 2837.462379]  syscall_return_slowpath+0x196/0x1b9
[ 2837.462379]  entry_SYSCALL_64_fastpath+0xab/0xad
[ 2837.462379] RIP: 0033:0x7f3ef3e6b9a7
[ 2837.462379] RSP: 002b:00007ffdd0d8de58 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
[ 2837.462379] RAX: 0000000000000000 RBX: 0000556f76a39060 RCX: 00007f3ef3e6b9a7
[ 2837.462379] RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000556f76a3f910
[ 2837.462379] RBP: 0000556f76a3f910 R08: 0000556f76a3e670 R09: 0000000000000015
[ 2837.462379] R10: 00000000000006b4 R11: 0000000000000246 R12: 00007f3ef436ce64
[ 2837.462379] R13: 0000000000000000 R14: 0000556f76a39240 R15: 00007ffdd0d8e0e0
[ 2837.519355] ---[ end trace e79345fe24b30b8d ]---
[ 2837.596256] ------------[ cut here ]------------
[ 2837.597625] WARNING: CPU: 8 PID: 2474 at fs/btrfs/extent-tree.c:5699 btrfs_free_block_groups+0x246/0x3eb [btrfs]
[ 2837.603547] Modules linked in: dm_flakey dm_mod ppdev parport_pc psmouse parport sg pcspkr acpi_cpufreq tpm_tis tpm_tis_core i2c_piix4 i2c_core evdev tpm button serio_raw sunrpc loop autofs4 ext4 crc16 jbd2 mbcache btrfs raid10 raid456 async_raid6_recov async_memcpy async_pq async_xor async_tx xor raid6_pq libcrc32c crc32c_generic raid1 raid0 multipath linear md_mod sr_mod cdrom sd_mod ata_generic virtio_scsi ata_piix libata virtio_pci virtio_ring virtio e1000 scsi_mod floppy
[ 2837.659372] CPU: 8 PID: 2474 Comm: umount Tainted: G        W       4.10.0-rc8-btrfs-next-43+ #1
[ 2837.663359] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.9.1-0-gb3ef39f-prebuilt.qemu-project.org 04/01/2014
[ 2837.663359] Call Trace:
[ 2837.663359]  dump_stack+0x68/0x92
[ 2837.663359]  __warn+0xc2/0xdd
[ 2837.663359]  warn_slowpath_null+0x1d/0x1f
[ 2837.663359]  btrfs_free_block_groups+0x246/0x3eb [btrfs]
[ 2837.663359]  close_ctree+0x1dd/0x2e1 [btrfs]
[ 2837.663359]  ? evict_inodes+0x132/0x141
[ 2837.663359]  btrfs_put_super+0x15/0x17 [btrfs]
[ 2837.663359]  generic_shutdown_super+0x6a/0xeb
[ 2837.663359]  kill_anon_super+0x12/0x1c
[ 2837.663359]  btrfs_kill_super+0x16/0x21 [btrfs]
[ 2837.663359]  deactivate_locked_super+0x30/0x68
[ 2837.663359]  deactivate_super+0x36/0x39
[ 2837.663359]  cleanup_mnt+0x58/0x76
[ 2837.663359]  __cleanup_mnt+0x12/0x14
[ 2837.663359]  task_work_run+0x77/0x9b
[ 2837.663359]  prepare_exit_to_usermode+0x9d/0xc5
[ 2837.663359]  syscall_return_slowpath+0x196/0x1b9
[ 2837.663359]  entry_SYSCALL_64_fastpath+0xab/0xad
[ 2837.663359] RIP: 0033:0x7f3ef3e6b9a7
[ 2837.663359] RSP: 002b:00007ffdd0d8de58 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
[ 2837.663359] RAX: 0000000000000000 RBX: 0000556f76a39060 RCX: 00007f3ef3e6b9a7
[ 2837.663359] RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000556f76a3f910
[ 2837.663359] RBP: 0000556f76a3f910 R08: 0000556f76a3e670 R09: 0000000000000015
[ 2837.663359] R10: 00000000000006b4 R11: 0000000000000246 R12: 00007f3ef436ce64
[ 2837.663359] R13: 0000000000000000 R14: 0000556f76a39240 R15: 00007ffdd0d8e0e0
[ 2837.739445] ---[ end trace e79345fe24b30b8e ]---
[ 2837.745595] ------------[ cut here ]------------
[ 2837.746412] WARNING: CPU: 8 PID: 2474 at fs/btrfs/extent-tree.c:5700 btrfs_free_block_groups+0x261/0x3eb [btrfs]
[ 2837.747955] Modules linked in: dm_flakey dm_mod ppdev parport_pc psmouse parport sg pcspkr acpi_cpufreq tpm_tis tpm_tis_core i2c_piix4 i2c_core evdev tpm button serio_raw sunrpc loop autofs4 ext4 crc16 jbd2 mbcache btrfs raid10 raid456 async_raid6_recov async_memcpy async_pq async_xor async_tx xor raid6_pq libcrc32c crc32c_generic raid1 raid0 multipath linear md_mod sr_mod cdrom sd_mod ata_generic virtio_scsi ata_piix libata virtio_pci virtio_ring virtio e1000 scsi_mod floppy
[ 2837.755395] CPU: 8 PID: 2474 Comm: umount Tainted: G        W       4.10.0-rc8-btrfs-next-43+ #1
[ 2837.756769] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.9.1-0-gb3ef39f-prebuilt.qemu-project.org 04/01/2014
[ 2837.758526] Call Trace:
[ 2837.758925]  dump_stack+0x68/0x92
[ 2837.759383]  __warn+0xc2/0xdd
[ 2837.759383]  warn_slowpath_null+0x1d/0x1f
[ 2837.759383]  btrfs_free_block_groups+0x261/0x3eb [btrfs]
[ 2837.759383]  close_ctree+0x1dd/0x2e1 [btrfs]
[ 2837.759383]  ? evict_inodes+0x132/0x141
[ 2837.759383]  btrfs_put_super+0x15/0x17 [btrfs]
[ 2837.759383]  generic_shutdown_super+0x6a/0xeb
[ 2837.759383]  kill_anon_super+0x12/0x1c
[ 2837.759383]  btrfs_kill_super+0x16/0x21 [btrfs]
[ 2837.759383]  deactivate_locked_super+0x30/0x68
[ 2837.759383]  deactivate_super+0x36/0x39
[ 2837.759383]  cleanup_mnt+0x58/0x76
[ 2837.759383]  __cleanup_mnt+0x12/0x14
[ 2837.759383]  task_work_run+0x77/0x9b
[ 2837.759383]  prepare_exit_to_usermode+0x9d/0xc5
[ 2837.759383]  syscall_return_slowpath+0x196/0x1b9
[ 2837.759383]  entry_SYSCALL_64_fastpath+0xab/0xad
[ 2837.759383] RIP: 0033:0x7f3ef3e6b9a7
[ 2837.759383] RSP: 002b:00007ffdd0d8de58 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
[ 2837.759383] RAX: 0000000000000000 RBX: 0000556f76a39060 RCX: 00007f3ef3e6b9a7
[ 2837.759383] RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000556f76a3f910
[ 2837.759383] RBP: 0000556f76a3f910 R08: 0000556f76a3e670 R09: 0000000000000015
[ 2837.759383] R10: 00000000000006b4 R11: 0000000000000246 R12: 00007f3ef436ce64
[ 2837.759383] R13: 0000000000000000 R14: 0000556f76a39240 R15: 00007ffdd0d8e0e0
[ 2837.777063] ---[ end trace e79345fe24b30b8f ]---
[ 2837.778235] ------------[ cut here ]------------
[ 2837.778856] WARNING: CPU: 8 PID: 2474 at fs/btrfs/extent-tree.c:9825 btrfs_free_block_groups+0x348/0x3eb [btrfs]
[ 2837.791385] Modules linked in: dm_flakey dm_mod ppdev parport_pc psmouse parport sg pcspkr acpi_cpufreq tpm_tis tpm_tis_core i2c_piix4 i2c_core evdev tpm button serio_raw sunrpc loop autofs4 ext4 crc16 jbd2 mbcache btrfs raid10 raid456 async_raid6_recov async_memcpy async_pq async_xor async_tx xor raid6_pq libcrc32c crc32c_generic raid1 raid0 multipath linear md_mod sr_mod cdrom sd_mod ata_generic virtio_scsi ata_piix libata virtio_pci virtio_ring virtio e1000 scsi_mod floppy
[ 2837.797711] CPU: 8 PID: 2474 Comm: umount Tainted: G        W       4.10.0-rc8-btrfs-next-43+ #1
[ 2837.798594] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.9.1-0-gb3ef39f-prebuilt.qemu-project.org 04/01/2014
[ 2837.800118] Call Trace:
[ 2837.800515]  dump_stack+0x68/0x92
[ 2837.801015]  __warn+0xc2/0xdd
[ 2837.801471]  warn_slowpath_null+0x1d/0x1f
[ 2837.801698]  btrfs_free_block_groups+0x348/0x3eb [btrfs]
[ 2837.801698]  close_ctree+0x1dd/0x2e1 [btrfs]
[ 2837.801698]  ? evict_inodes+0x132/0x141
[ 2837.801698]  btrfs_put_super+0x15/0x17 [btrfs]
[ 2837.801698]  generic_shutdown_super+0x6a/0xeb
[ 2837.801698]  kill_anon_super+0x12/0x1c
[ 2837.801698]  btrfs_kill_super+0x16/0x21 [btrfs]
[ 2837.801698]  deactivate_locked_super+0x30/0x68
[ 2837.801698]  deactivate_super+0x36/0x39
[ 2837.801698]  cleanup_mnt+0x58/0x76
[ 2837.801698]  __cleanup_mnt+0x12/0x14
[ 2837.801698]  task_work_run+0x77/0x9b
[ 2837.801698]  prepare_exit_to_usermode+0x9d/0xc5
[ 2837.801698]  syscall_return_slowpath+0x196/0x1b9
[ 2837.801698]  entry_SYSCALL_64_fastpath+0xab/0xad
[ 2837.801698] RIP: 0033:0x7f3ef3e6b9a7
[ 2837.801698] RSP: 002b:00007ffdd0d8de58 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
[ 2837.801698] RAX: 0000000000000000 RBX: 0000556f76a39060 RCX: 00007f3ef3e6b9a7
[ 2837.801698] RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000556f76a3f910
[ 2837.801698] RBP: 0000556f76a3f910 R08: 0000556f76a3e670 R09: 0000000000000015
[ 2837.801698] R10: 00000000000006b4 R11: 0000000000000246 R12: 00007f3ef436ce64
[ 2837.801698] R13: 0000000000000000 R14: 0000556f76a39240 R15: 00007ffdd0d8e0e0
[ 2837.818441] ---[ end trace e79345fe24b30b90 ]---
[ 2837.818991] BTRFS info (device sdc): space_info 1 has 7974912 free, is not full
[ 2837.819830] BTRFS info (device sdc): space_info total=8388608, used=417792, pinned=0, reserved=0, may_use=18446744073709547520, readonly=0

What happens in the above example is the following:

1) When punching the hole, at btrfs_punch_hole(), the variable tail_len
   is set to 2048 (as tail_start is 148Kb + 1 and offset + len is 150Kb).
   This results in the creation of an extent map with a length of 2Kb
   starting at file offset 148Kb, through find_first_non_hole() ->
   btrfs_get_extent().

2) The second write (first write after the hole punch operation), sets
   the range [50Kb, 152Kb[ to delalloc.

3) The third write, at btrfs_find_new_delalloc_bytes(), sees the extent
   map covering the range [148Kb, 150Kb[ and ends up calling
   set_extent_bit() for the same range, which results in splitting an
   existing extent state record, covering the range [148Kb, 152Kb[ into
   two 2Kb extent state records, covering the ranges [148Kb, 150Kb[ and
   [150Kb, 152Kb[.

4) Finally at lock_and_cleanup_extent_if_need(), immediately after calling
   btrfs_find_new_delalloc_bytes() we clear the delalloc bit from the
   range [100Kb, 152Kb[ which results in the btrfs_clear_bit_hook()
   callback being invoked against the two 2Kb extent state records that
   cover the ranges [148Kb, 150Kb[ and [150Kb, 152Kb[. When called against
   the first 2Kb extent state, it calls btrfs_delalloc_release_metadata()
   with a length argument of 2048 bytes. That function rounds up the length
   to a sector size aligned length, so it ends up considering a length of
   4096 bytes, and then calls calc_csum_metadata_size() which results in
   decrementing the inode's csum_bytes counter by 4096 bytes, so after
   it stays a value of 0 bytes. Then the same happens when
   btrfs_clear_bit_hook() is called against the second extent state that
   has a length of 2Kb, covering the range [150Kb, 152Kb[, the length is
   rounded up to 4096 and calc_csum_metadata_size() ends up being called
   to decrement 4096 bytes from the inode's csum_bytes counter, which
   at that time has a value of 0, leading to an underflow, which is
   exactly what triggers the first warning, at btrfs_destroy_inode().
   All the other warnings relate to several space accounting counters
   that underflow as well due to similar reasons.

A similar case but where the hole punching operation creates an extent map
with a start offset not aligned to the sector size is the following:

  $ mkfs.btrfs -f /dev/sdb
  $ mount /dev/sdb /mnt
  $ xfs_io -f -c "fpunch 695K 820K" $SCRATCH_MNT/bar
  $ xfs_io -c "pwrite -S 0xaa 1008K 307K" $SCRATCH_MNT/bar
  $ xfs_io -c "pwrite -S 0xbb -b 630K 1073K 630K" $SCRATCH_MNT/bar
  $ xfs_io -c "pwrite -S 0xcc -b 459K 1068K 459K" $SCRATCH_MNT/bar
  $ umount /mnt

During the unmount operation we get similar traces for the same reasons as
in the first example.

So fix the hole punching operation to make sure it never creates extent
maps with a length that is not aligned to the sector size nor with a start
offset that is not aligned to the sector size, as this breaks all
assumptions and it's a land mine.

Fixes: d77815461f ("btrfs: Avoid trucating page or punching hole in a already existed hole.")
Cc: <stable@vger.kernel.org>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-21 16:52:45 +02:00
Jeff Mahoney cddf3b2cb3 btrfs: add cond_resched to btrfs_qgroup_trace_leaf_items
On an uncontended system, we can end up hitting soft lockups while
doing replace_path.  At the core, and frequently called is
btrfs_qgroup_trace_leaf_items, so it makes sense to add a cond_resched
there.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-21 15:48:01 +02:00
Nikolay Borisov 7dfb8be11b btrfs: Round down values which are written for total_bytes_size
We got an internal report about a file system not wanting to mount
following 99e3ecfcb9 ("Btrfs: add more validation checks for
superblock").

BTRFS error (device sdb1): super_total_bytes 1000203816960 mismatch with
fs_devices total_rw_bytes 1000203820544

Subtracting the numbers we get a difference of less than a 4kb. Upon
closer inspection it became apparent that mkfs actually rounds down the
size of the device to a multiple of sector size. However, the same
cannot be said for various functions which modify the total size and are
called from btrfs_balance as well as when adding a new device. So this
patch ensures that values being saved into on-disk data structures are
always rounded down to a multiple of sectorsize.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-20 14:22:48 +02:00
Nikolay Borisov eca152edf5 btrfs: Manually implement device_total_bytes getter/setter
The device->total_bytes member needs to always be rounded down to sectorsize
so that it corresponds to the value of super->total_bytes. However, there are
multiple places where the setter is fed a value which is not rounded which
can cause a fs to be unmountable due to the check introduced in
99e3ecfcb9 ("Btrfs: add more validation checks for superblock"). This patch
implements the getter/setter manually so that in a later patch I can add
necessary code to catch offenders.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-20 14:22:48 +02:00
David Sterba 0d0c71b317 btrfs: obsolete and remove mount option alloc_start
The mount option alloc_start was used in the past for debugging and
stressing the chunk allocator. Not meant to be used by users, so we're
not breaking anybody's setup.

There was some added complexity handling changes of the value and when
it was not same as default. Such code has likely been untested and I
think it's better to remove it.

This patch kills all use of alloc_start, and by doing that also fixes
a bug when alloc_size is set, potentially called from statfs:

in btrfs_calc_avail_data_space, traversing the list in RCU, the RCU
protection is temporarily dropped so btrfs_account_dev_extents_size can
be called and then RCU is locked again! Doing that inside
list_for_each_entry_rcu is just asking for trouble, but unlikely to be
observed in practice.

Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-20 14:22:48 +02:00
David Sterba fac03c8dae btrfs: move fs_info::fs_frozen to the flags
We can keep the state among the other fs_info flags, there's no reason
why fs_frozen would need to be separate.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-20 14:22:42 +02:00
David Sterba 79b4f4c605 btrfs: cleanup duplicate return value in insert_inline_extent
The pattern when err is used for function exit and ret is used for
return values of callees is not used here.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-20 14:22:12 +02:00
David Sterba 6165572c11 btrfs: use GFP_KERNEL in btrfs_init_dev_replace_tgtdev
The function is called from ioctl context and we don't hold any locks
that take part in writeback. Right now it's only fs_info::volume_mutex.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-19 18:26:04 +02:00
David Sterba 6a44517d79 btrfs: use GFP_KERNEL in btrfs_calc_avail_data_space
We don't hold any locks here. Inidirectly called from statfs.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-19 18:26:04 +02:00
Nikolay Borisov 0eee8a494e btrfs: Use btrfs_space_info_used instead of opencoding it
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-19 18:26:04 +02:00
Anand Jain 4fc6441aac btrfs: wait part of the write_dev_flush() can be separated out
Submit and wait parts of write_dev_flush() can be split into two
separate functions for better readability.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-19 18:26:04 +02:00
Anand Jain cea7c8bf77 btrfs: remove redundant null bdev counting during flush submission
There is no extra benefit to count null bdev during the submit loop,
as these null devices will be anyway checked during command
completion device loop just after the submit loop. We are holding the
device_list_mutex, the device->bdev status won't change in between.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-19 18:26:04 +02:00
Anand Jain 12b9bf0b94 btrfs: write_dev_flush does not return ENOMEM anymore
Since commit "btrfs: btrfs_io_bio_alloc never fails, skip error handling"
write_dev_flush will not return ENOMEM in the sending part. We do not
need to check for it in the callers.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ updated changelog ]
Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-19 18:26:04 +02:00
Timofey Titovets 170607ebd9 Btrfs: compression must free at least one sector size
We already skip storing data where compression does not make the result
at least one byte less.  Let's make the logic better and check
that compression frees at least one sector size of bytes, otherwise it's
not that useful.

Signed-off-by: Timofey Titovets <nefelim4ag@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ changelog updated ]
Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-19 18:26:04 +02:00
David Sterba c5e4c3d750 btrfs: sink gfp parameter to btrfs_io_bio_alloc
We can hardcode GFP_NOFS to btrfs_io_bio_alloc, although it means we
change it back from GFP_KERNEL in scrub. I'd rather save a few stack
bytes from not passing the gfp flags in the remaining, more imporatant,
contexts and the bio allocating API now looks more consistent.

Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-19 18:26:04 +02:00
David Sterba 184f999e12 btrfs: add helper to initialize the non-bio part of btrfs_io_bio
We use btrfs_bioset for bios and ask to allocate the entire size of
btrfs_io_bio from btrfs bio_alloc_bioset. The member 'bio' is
initialized but the bytes from 0 to offset of 'bio' are left
uninitialized. Although we initialize some of the members in our
helpers, we should initialize the whole structures.

Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-19 18:26:03 +02:00
David Sterba fa1bcbe0a5 btrfs: document mandatory order of bio in btrfs_io_bio
Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-19 18:26:03 +02:00
Liu Bo ef7cdac101 Btrfs: skip checksum verification if IO error occurs
Currently dio read also goes to verify checksum if -EIO has been returned,
although it usually fails on checksum, it's not necessary at all, we could
directly check if there is another copy to read.

And with this, the behavior of dio read is now consistent with that of
buffered read.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ use bool for uptodate ]
Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-19 18:26:03 +02:00
Liu Bo e3d37faba2 Btrfs: tolerate errors if we have retried successfully
With raid1 profile, dio read isn't tolerating IO errors if read length is
less than the stripe length (64K).

Our bio didn't get split in btrfs_submit_direct_hook() if (dip->flags &
BTRFS_DIO_ORIG_BIO_SUBMITTED) is true and that happens when the read
length is less than 64k.  In this case, if the underlying device returns
error somehow, bio->bi_error has recorded that error.

If we could recover the correct data from another copy in profile raid1/10/5/6,
with btrfs_subio_endio_read() returning 0, bio would have the correct data in
its vector, but bio->bi_error is not updated accordingly so that the following
dio_end_io(dio_bio, bio->bi_error) makes directIO think this read has failed.

This fixes the problem by setting bio's error to 0 if a good copy has been
found.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-19 18:26:03 +02:00
David Sterba c821e7f3da btrfs: pass bytes to btrfs_bio_alloc
Most callers of btrfs_bio_alloc convert from bytes to sectors. Hide that
in the helper and simplify the logic in the callsers.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-19 18:26:03 +02:00
David Sterba 9886b17433 btrfs: opencode trivial compressed_bio_alloc, simplify error handling
compressed_bio_alloc is now a trivial wrapper around btrfs_bio_alloc, no
point keeping it. The error handling can be simplified, as we know
btrfs_bio_alloc will never fail.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-19 18:26:03 +02:00
David Sterba 9f2179a5e7 btrfs: remove redundant parameters from btrfs_bio_alloc
All callers pass gfp_flags=GFP_NOFS and nr_vecs=BIO_MAX_PAGES.

submit_extent_page adds __GFP_HIGH that does not make a difference in
our case as it allows access to memory reserves but otherwise does not
change the constraints.

Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-19 18:26:03 +02:00
David Sterba 8b6c1d56f2 btrfs: sink gfp parameter to btrfs_bio_clone
All callers pass GFP_NOFS.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-19 18:26:03 +02:00
David Sterba e4f5690386 btrfs: btrfs_io_bio_alloc never fails, skip error handling
Update direct callers of btrfs_io_bio_alloc that do error handling, that
we can now remove.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-19 18:26:02 +02:00
David Sterba 3aa8e074ab btrfs: btrfs_bio_clone never fails, skip error handling
Update direct callers of btrfs_bio_clone that do error handling, that we
can now remove.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-19 18:26:02 +02:00
David Sterba 0c4dd97c5e btrfs: btrfs_bio_alloc never fails, skip error handling
Update direct callers of btrfs_bio_alloc that do error handling, that we
can now remove.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-19 18:26:02 +02:00
David Sterba 6e707bcd1f btrfs: bioset allocations will never fail, adapt our helpers
Christoph pointed out that bio allocations backed by a bioset will never
fail.  As we always use a bioset for all bio allocations, we can skip
the error handling.  This patch adjusts our low-level helpers, the
cascaded changes to all callers will come next.

CC: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-19 18:26:02 +02:00
David Sterba 6acafd1eff btrfs: switch to kvmalloc and GFP_KERNEL in lzo/zlib alloc_workspace
The compression workspace buffers are larger than a page so we use
vmalloc, unconditionally. This is not always necessary as there might be
contiguous memory available.

Let's use the kvmalloc helpers that will try kmalloc first and fallback
to vmalloc. For that they require GFP_KERNEL flags. As we now have the
alloc_workspace calls protected by memalloc_nofs in the critical
contexts, we can safely use GFP_KERNEL.

Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-19 18:26:02 +02:00
David Sterba 389a6cfc2a btrfs: switch kmallocs to GFP_KERNEL in lzo/zlib alloc_workspace
As alloc_workspace is now protected by memalloc_nofs where needed,
we can switch the kmalloc to use GFP_KERNEL.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-19 18:26:02 +02:00
David Sterba fe30853307 btrfs: add memalloc_nofs protections around alloc_workspace callback
The workspaces are preallocated at the beginning where we can safely use
GFP_KERNEL, but in some cases the find_workspace might reach the
allocation again, now in a more restricted context when the bios or
pages are being compressed.

To avoid potential lockup when alloc_workspace -> vmalloc would silently
use the GFP_KERNEL, add the memalloc_nofs helpers around the critical
call site.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-19 18:26:02 +02:00
David Sterba adf0212396 btrfs: adjust includes after vmalloc removal
As we don't use vmalloc/vzalloc/vfree directly in ctree.c, we can now
use the proper header that defines kvmalloc.

Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-19 18:26:02 +02:00
David Sterba f54de068dd btrfs: use GFP_KERNEL in init_ipath
Now that init_ipath is called either from a safe context or with
memalloc_nofs protection, we can switch to GFP_KERNEL allocations in
init_path and init_data_container.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-19 18:26:02 +02:00
David Sterba de2491fdef btrfs: scrub: add memalloc_nofs protection around init_ipath
init_ipath is called from a safe ioctl context and from scrub when
printing an error.  The protection is added for three reasons:

* init_data_container calls vmalloc and this does not work as expected
  in the GFP_NOFS context, so this silently does GFP_KERNEL and might
  deadlock in some cases
* keep the context constraint of GFP_NOFS, used by scrub
* we want to use GFP_KERNEL unconditionally inside init_ipath or its
  callees

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-19 18:26:02 +02:00
David Sterba f11f74416a btrfs: send: use kvmalloc in iterate_dir_item
We use a growing buffer for xattrs larger than a page size, at some
point vmalloc is unconditionally used for larger buffers. We can still
try to avoid it using the kvmalloc helper.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-19 18:26:02 +02:00