Commit Graph

800 Commits

Author SHA1 Message Date
Nikolay Borisov
fd649f10c3 btrfs: Fix use-after-free when cleaning up fs_devs with a single stale device
Commit 4fde46f0cc ("Btrfs: free the stale device") introduced
btrfs_free_stale_device which iterates the device lists for all
registered btrfs filesystems and deletes those devices which aren't
mounted. In a btrfs_devices structure has only 1 device attached to it
and it is unused then btrfs_free_stale_devices will proceed to also free
the btrfs_fs_devices struct itself. Currently this leads to a use after
free since list_for_each_entry will try to perform a check on the
already freed memory to see if it has to terminate the loop.

The fix is to use 'break' when we know we are freeing the current
fs_devs.

Fixes: 4fde46f0cc ("Btrfs: free the stale device")
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-02-05 17:15:14 +01:00
Anand Jain
3acbcbfc8f btrfs: drop devid as device_list_add() arg
As struct btrfs_disk_super is being passed, so it can get devid
the same way its parent does.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-29 19:31:16 +01:00
Anand Jain
e124ece53e btrfs: get device pointer from device_list_add()
Instead of pointer to btrfs_fs_devices as an arg in device_list_add()
better to get pointer to btrfs_device as return value, then we have
both, pointer to btrfs_device and btrfs_fs_devices. btrfs_device is
needed to handle reappearing missing device.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-29 19:31:15 +01:00
Anand Jain
f2788d2f76 btrfs: set the total_devices in device_list_add()
There is no other parent for device_list_add() except for
btrfs_scan_one_device(), which would set btrfs_fs_devices::total_devices
if device_list_add is successful and this can be done with in
device_list_add() itself.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 20:25:56 +01:00
Anand Jain
327f18cc7f btrfs: move pr_info into device_list_add
Commit 60999ca4b4 ("btrfs: make device scan less noisy")
adds return value 1 to device_list_add(), so that parent function can
call pr_info only when new device is added. Move the pr_info() part
into device_list_add() so that this function can be kept simple.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 20:25:54 +01:00
Anand Jain
d8367db30a btrfs: make btrfs_free_stale_devices() to match the path
The btrfs_free_stale_devices() is updated to match for the given device
path and delete it. (It searches for only unmounted list of devices.)
Also drop the comment about different path being used for the same
device, since now we will have cli to clean any device that's not a
concern any more.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 20:25:52 +01:00
Anand Jain
0d34097f66 btrfs: rename btrfs_free_stale_devices() arg to skip_dev
No functional changes.
Rename btrfs_free_stale_devices() arg to skip_dev, so that it
reflects what that arg for.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 20:25:50 +01:00
Anand Jain
522f1b45e4 btrfs: make btrfs_free_stale_devices() argument optional
This updates btrfs_free_stale_devices() helper function to delete all
unmouted devices, when arg is NULL.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 20:25:48 +01:00
Anand Jain
38cf665d33 btrfs: make btrfs_free_stale_device() to iterate all stales
Let the list iterator iterate further and find other stale
devices and delete it. This is in preparation to add support
for user land request-able stale devices cleanup. Also rename
btrfs_free_stale_device() to btrfs_free_stale_devices().

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 20:25:47 +01:00
Anand Jain
a848b3e547 btrfs: no need to check for btrfs_fs_devices::seeding
There is no need to check for btrfs_fs_devices::seeding when we
have checked for btrfs_fs_devices::opened, because we can't sprout
without its seed FS being opened.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 20:25:44 +01:00
Matthew Wilcox
3cbf26da5e btrfs: Remove unused readahead spinlock
The reada_lock in struct btrfs_device was only initialised, and not
actually used.  That's good because there's another lock also called
reada_lock in the btrfs_fs_info that was quite heavily used.  Remove
this one.

Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:21 +01:00
Anand Jain
1c94da9dd9 btrfs: cleanup btrfs_free_stale_device() usage
We call btrfs_free_stale_device() only when we alloc a new struct
btrfs_device (ret=1), so move it closer to where we alloc the new
device. Also drop the comments.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:21 +01:00
Liu Bo
a6f93c71d4 Btrfs: avoid losing data raid profile when deleting a device
We've avoided data losing raid profile when doing balance, but it
turns out that deleting a device could also result in the same
problem.

Say we have 3 disks, and they're created with '-d raid1' profile.

- We have chunk P (the only data chunk on the empty btrfs).

- Suppose that chunk P's two raid1 copies reside in disk A and disk B.

- Now, 'btrfs device remove disk B'
         btrfs_rm_device()
	   -> btrfs_shrink_device()
	      -> btrfs_relocate_chunk() #relocate any chunk on disk B
	      	 			 to other places.

- Chunk P will be removed and a new chunk will be created to hold
  those data, but as chunk P is the only one holding raid1 profile,
  after it goes away, the new chunk will be created as single profile
  which is our default profile.

This fixes the problem by creating an empty data chunk before
relocating the data chunk.

Metadata/System chunk are supposed to have non-zero bytes all the time
so their raid profile is preserved.

Reported-by: James Alandt <James.Alandt@wdc.com>
Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:20 +01:00
Anand Jain
05a5c55dfc btrfs: minor style cleanups in btrfs_scan_one_device
Assign ret = -EINVAL where it is actually required.
Remove { } around single line if else code.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:20 +01:00
Liu Bo
8810f7517a Btrfs: make raid6 rebuild retry more
There is a scenario that can end up with rebuild process failing to
return good content, i.e.
suppose that all disks can be read without problems and if the content
that was read out doesn't match its checksum, currently for raid6
btrfs at most retries twice,

- the 1st retry is to rebuild with all other stripes, it'll eventually
  be a raid5 xor rebuild,
- if the 1st fails, the 2nd retry will deliberately fail parity p so
  that it will do raid6 style rebuild,

however, the chances are that another non-parity stripe content also
has something corrupted, so that the above retries are not able to
return correct content, and users will think of this as data loss.
More seriouly, if the loss happens on some important internal btree
roots, it could refuse to mount.

This extends btrfs to do more retries and each retry fails only one
stripe.  Since raid6 can tolerate 2 disk failures, if there is one
more failure besides the failure on which we're recovering, this can
always work.

The worst case is to retry as many times as the number of raid6 disks,
but given the fact that such a scenario is really rare in practice,
it's still acceptable.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:20 +01:00
Anand Jain
6528b99d3d btrfs: factor btrfs_check_rw_degradable() to check given device
Update btrfs_check_rw_degradable() to check against the given device if
its lost.

We can use this function to know if the volume is going to be in
degraded mode OR failed state, when the given device fails.  Which is
needed when we are handling the device failed state.

A preparatory patch does not affect the flow as such.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
[ enhance comment ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:20 +01:00
Nikolay Borisov
3e798068a8 btrfs: Remove pair of bio_get/put in btrfs_schedule_bio
This code was added in 492bb6deee ("Btrfs: Hold a reference on bios
during submit_bio, add some extra bio checks"). However, holding a
reference on a bio is necessary only if it's going to be referenced
after the submit_bio returns and the bio is completed. In this
particular instance this is not the case so there is no need to hold
an extra reference since we directly return.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:16 +01:00
Anand Jain
401e29c124 btrfs: cleanup device states define BTRFS_DEV_STATE_REPLACE_TGT
Currently device state is being managed by each individual int
variable such as struct btrfs_device::is_tgtdev_for_dev_replace.
Instead of that declare btrfs_device::dev_state
BTRFS_DEV_STATE_MISSING and use the bit operations.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
[ whitespace adjustments ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:15 +01:00
Anand Jain
e6e674bd4d btrfs: cleanup device states define BTRFS_DEV_STATE_MISSING
Currently device state is being managed by each individual int
variable such as struct btrfs_device::missing. Instead of that
declare btrfs_device::dev_state BTRFS_DEV_STATE_MISSING and use
the bit operations.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by : Nikolay Borisov <nborisov@suse.com>
[ whitespace adjustments ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:15 +01:00
Anand Jain
e12c96214d btrfs: cleanup device states define BTRFS_DEV_STATE_IN_FS_METADATA
Currently device state is being managed by each individual int
variable such as struct btrfs_device::in_fs_metadata. Instead of
that declare device state BTRFS_DEV_STATE_IN_FS_METADATA and use
the bit operations.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
[ whitespace adjustments ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:15 +01:00
Anand Jain
ebbede42d4 btrfs: cleanup device states define BTRFS_DEV_STATE_WRITEABLE
Currently device state is being managed by each individual int
variable such as struct btrfs_device::writeable. Instead of that
declare device state BTRFS_DEV_STATE_WRITEABLE and use the
bit operations.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
[ whitespace adjustments ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:15 +01:00
Anand Jain
38b5f68e98 btrfs: drop btrfs_device::can_discard to query directly
We can query the bdev directly when needed at btrfs_discard_extent()
so drop btrfs_device::can_discard.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Suggested-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:14 +01:00
Anand Jain
0fb08bccbc btrfs: factor __btrfs_open_devices() to create btrfs_open_one_device()
No functional changes, create btrfs_open_one_device() from
__btrfs_open_devices(). This is a preparatory work to add dynamic
device scan.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
[ minor whitespace fixes ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:13 +01:00
Anand Jain
9f050db43e btrfs: move check for device generation to the last
No functional changes. This helps to move the entire section into
a new function.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:13 +01:00
Anand Jain
71f8a8d2c1 btrfs: set fs_devices->seed directly
This is in preparation to move a section of code in __btrfs_open_devices()
into a new function so that it can be reused. As we set seeding if any of
the device is having SB flag BTRFS_SUPER_FLAG_SEEDING, so do it in the
device list loop itself. No functional changes.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:13 +01:00
David Sterba
08ffcae8c9 btrfs: simplify btrfs_close_bdev
Split the conditions a bit.

Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:12 +01:00
David Sterba
9c6b1c4de1 btrfs: document device locking
Overview of the main locks protecting various device-related structures.

Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:12 +01:00
David Sterba
5c4cf6c91d btrfs: simplify exit paths in btrfs_init_new_device
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:12 +01:00
David Sterba
55de480346 btrfs: use free_device where opencoded
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:12 +01:00
David Sterba
48dae9cf3f btrfs: introduce free_device helper
A helper to free a device and all it's dynamically allocated members,
like the rcu_string name or flush_bio. This is going to replace all
open coded places.

Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:11 +01:00
David Sterba
f06c5965ab btrfs: rename device free rcu helper to free_device_rcu
Make it clear that it is an RCU helper, we want to use the name
free_device for a wrapper freeing all device members.

Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:11 +01:00
Anand Jain
c74a0b0237 btrfs: rename btrfs_add_device to btrfs_add_dev_item
Function btrfs_add_device() is adding the device item so rename to
reflect that in the function. Similarly we have btrfs_rm_dev_item().

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:11 +01:00
Anand Jain
2c9973847f btrfs: move volume_mutex into the btrfs_rm_device()
A cleanup patch no functional change, we hold volume_mutex before
calling btrfs_rm_device, so move it into the function itself.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:11 +01:00
Liu Bo
47dba17171 Btrfs: remove rcu_barrier in btrfs_close_devices
It was introduced because btrfs used to do blkdev_put in a deferred
work, now that btrfs has blkdev_put in place, this rcu_barrier can be
removed.

modprobe -r btrfs will do btrfs_cleanup_fs_uuids(), where it cleanup
every %fs_devices on the list, but when we do btrfs_close_devices(), we
have replaced the devices on the list with dummy ones which only have
the same name and uuid, so modprobe -r btrfs will free those instead of
what we were using, this change won't cause a problem for it.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ copied 2nd paragraph from mailinglist discussion ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:11 +01:00
Nikolay Borisov
9deae96892 btrfs: Fix memory barriers usage with device stats counters
Commit addc3fa74e ("Btrfs: Fix the problem that the dirty flag of dev
stats is cleared") reworked the way device stats changes are tracked. A
new atomic dev_stats_ccnt counter was introduced which is incremented
every time any of the device stats counters are changed. This serves as
a flag whether there are any pending stats changes. However, this patch
only partially implemented the correct memory barriers necessary:

- It only ordered the stores to the counters but not the reads e.g.
  btrfs_run_dev_stats
- It completely omitted any comments documenting the intended design and
  how the memory barriers pair with each-other

This patch provides the necessary comments as well as adds a missing
smp_rmb in btrfs_run_dev_stats. Furthermore since dev_stats_cnt is only
a snapshot at best there was no point in reading the counter twice -
once in btrfs_dev_stats_dirty and then again when assigning stats_cnt.
Just collapse both reads into 1.

Fixes: addc3fa74e ("Btrfs: Fix the problem that the dirty flag of dev stats is cleared")
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:10 +01:00
Anand Jain
1cb34c8ecd btrfs: clean up btrfs_dev_stat_inc usage
btrfs_end_bio() is using btrfs_dev_stat_inc() and then
btrfs_dev_stat_print_on_error() separately instead use
btrfs_dev_stat_inc_and_print() directly.

As of now there isn't any bio in btrfs which is - a non-empty write and
also the REQ_PREFLUSH flag is set. So in actual the condition

   if (bio->bi_opf & REQ_PREFLUSH)

is never true in btrfs_end_bio(), and so there won't be any redundant
error log by using btrfs_dev_stat_inc_and_print() separately one for
write and another for flush.

This consolidation will help to add the device critical error handles in
the function btrfs_dev_stat_inc_and_print() and which can be renamed as
needed.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:10 +01:00
Liu Bo
9f5316c17b Btrfs: free btrfs_device in place
It's pointless to defer it to a kthread helper as we're not under a
special context.

For reference, commit 1f78160ce1 ("Btrfs: using rcu lock in the reader
side of devices list") introduced RCU freeing for device structures.

Originally the blkdev_put was called from free_device and rcu_barrier had
to be called. This is no longer required, bdev and our device structures
are now freed separately.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ enhance changelog ]
Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:10 +01:00
Linus Torvalds
89876f275e for-4.15-rc7-tag
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Merge tag 'for-4.15-rc7-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs fixes from David Sterba:
 "We have two more fixes for 4.15, both aimed for stable.

  The leak fix is obvious, the second patch fixes a bug revealed by the
  refcount API, when it behaves differently than previous atomic_t and
  reports refs going from 0 to 1 in one case"

* tag 'for-4.15-rc7-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: fix refcount_t usage when deleting btrfs_delayed_nodes
  btrfs: Fix flush bio leak
2018-01-05 13:02:46 -08:00
Nikolay Borisov
beed9263f4 btrfs: Fix flush bio leak
Commit e0ae999414 ("btrfs: preallocate device flush bio") reworked
the way the flush bio is allocated and used. Concretely it allocates
the bio in __alloc_device and then re-uses it multiple times with a
very simple endio routine that just calls complete() without consuming
a reference. Allocated bios by default come with a ref count of 1,
which is then consumed by the endio routine (or not, in which case they
should be bio_put by the caller). The way the impleementation works now
is that the flush bio has a refcount of 2 and we only ever bio_put it
once, leaving it to hang indefinitely. Fix this by removing the extra
bio_get in __alloc_device.

Fixes: e0ae999414 ("btrfs: preallocate device flush bio")
Signed-off-by: Nikolay Borisov <nborisov@suse.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>
2018-01-02 18:00:13 +01:00
Linus Torvalds
26cd94744e for-4.15-rc2-tag
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Merge tag 'for-4.15-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs fixes from David Sterba:
 "We've collected some fixes in since the pre-merge window freeze.

  There's technically only one regression fix for 4.15, but the rest
  seems important and candidates for stable.

   - fix missing flush bio puts in error cases (is serious, but rarely
     happens)

   - fix reporting stat::st_blocks for buffered append writes

   - fix space cache invalidation

   - fix out of bound memory access when setting zlib level

   - fix potential memory corruption when fsync fails in the middle

   - fix crash in integrity checker

   - incremetnal send fix, path mixup for certain unlink/rename
     combination

   - pass flags to writeback so compressed writes can be throttled
     properly

   - error handling fixes"

* tag 'for-4.15-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  Btrfs: incremental send, fix wrong unlink path after renaming file
  btrfs: tree-checker: Fix false panic for sanity test
  Btrfs: fix list_add corruption and soft lockups in fsync
  btrfs: Fix wild memory access in compression level parser
  btrfs: fix deadlock when writing out space cache
  btrfs: clear space cache inode generation always
  Btrfs: fix reported number of inode blocks after buffered append writes
  Btrfs: move definition of the function btrfs_find_new_delalloc_bytes
  Btrfs: bail out gracefully rather than BUG_ON
  btrfs: dev_alloc_list is not protected by RCU, use normal list_del
  btrfs: add missing device::flush_bio puts
  btrfs: Fix transaction abort during failure in btrfs_rm_dev_item
  Btrfs: add write_flags for compression bio
2017-11-29 14:26:50 -08:00
Linus Torvalds
1751e8a6cb Rename superblock flags (MS_xyz -> SB_xyz)
This is a pure automated search-and-replace of the internal kernel
superblock flags.

The s_flags are now called SB_*, with the names and the values for the
moment mirroring the MS_* flags that they're equivalent to.

Note how the MS_xyz flags are the ones passed to the mount system call,
while the SB_xyz flags are what we then use in sb->s_flags.

The script to do this was:

    # places to look in; re security/*: it generally should *not* be
    # touched (that stuff parses mount(2) arguments directly), but
    # there are two places where we really deal with superblock flags.
    FILES="drivers/mtd drivers/staging/lustre fs ipc mm \
            include/linux/fs.h include/uapi/linux/bfs_fs.h \
            security/apparmor/apparmorfs.c security/apparmor/include/lib.h"
    # the list of MS_... constants
    SYMS="RDONLY NOSUID NODEV NOEXEC SYNCHRONOUS REMOUNT MANDLOCK \
          DIRSYNC NOATIME NODIRATIME BIND MOVE REC VERBOSE SILENT \
          POSIXACL UNBINDABLE PRIVATE SLAVE SHARED RELATIME KERNMOUNT \
          I_VERSION STRICTATIME LAZYTIME SUBMOUNT NOREMOTELOCK NOSEC BORN \
          ACTIVE NOUSER"

    SED_PROG=
    for i in $SYMS; do SED_PROG="$SED_PROG -e s/MS_$i/SB_$i/g"; done

    # we want files that contain at least one of MS_...,
    # with fs/namespace.c and fs/pnode.c excluded.
    L=$(for i in $SYMS; do git grep -w -l MS_$i $FILES; done| sort|uniq|grep -v '^fs/namespace.c'|grep -v '^fs/pnode.c')

    for f in $L; do sed -i $f $SED_PROG; done

Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-27 13:05:09 -08:00
David Sterba
619c47f3d4 btrfs: dev_alloc_list is not protected by RCU, use normal list_del
The dev_alloc_list list could be protected by various mutexes,
depending on the context. The list tracks devices that can take part of
allocating new chunks, so the closest mutex is chunk_mutex. Adding a new
device from inside the ADD_DEV ioctl will need device_list_mutex and
registering a new device from the ioctl needs uuid_mutex.

All mutexes naturally guarantee exclusivity against the same context.
The device ownership can move between the contexts and the exclusivity
is guaranteed by other means, eg. during the mount with the uuid_mutex.

There's no RCU involved for dev_alloc_list.

Signed-off-by: David Sterba <dsterba@suse.com>
2017-11-15 14:46:12 +01:00
David Sterba
3065ae5b85 btrfs: add missing device::flush_bio puts
This fixes potential bio leaks, in several error paths. Unfortunatelly
the device structure freeing is opencoded in many places and I missed
them when introducing the flush_bio.

Most of the time, devices get freed through call_rcu(..., free_device),
so it at least it's not that easy to hit the leak, but it's still
possible through the path that frees stale devices.

Fixes: e0ae999414 ("btrfs: preallocate device flush bio")
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-11-15 14:45:26 +01:00
Nikolay Borisov
5e9f2ad5b2 btrfs: Fix transaction abort during failure in btrfs_rm_dev_item
btrfs_rm_dev_item calls several function under an active transaction,
however it fails to abort it if an error happens. Fix this by adding
explicit btrfs_abort_transaction/btrfs_end_transaction calls.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-11-15 14:44:44 +01:00
Anand Jain
6dd38f81f9 btrfs: remove BUG_ON in btrfs_rm_dev_replace_free_srcdev()
That was only an extra check to tackle a few bugs around this area, now
its safe to remove it.  Replace it by an ASSERT.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-11-01 20:45:34 +01:00
Anand Jain
102ed2c5ff btrfs: fix false EIO for missing device
When one of the device is missing, bbio_error() takes care of setting
the error status. And if its only IO that is pending in that stripe, it
fails to check the status of the other IO at %bbio_error before setting
the error %bi_status for the %orig_bio. Fix this by checking if
%bbio->error has exceeded the %bbio->max_errors.

Reproducer as below fdatasync error is seen intermittently.

 mount -o degraded /dev/sdc /btrfs
 dd status=none if=/dev/zero of=$(mktemp /btrfs/XXX) bs=4096 count=1 conv=fdatasync

 dd: fdatasync failed for ‘/btrfs/LSe’: Input/output error

 The reason for the intermittences of the problem is because
 the following conditions have to be met, which depends on timing:
 In btrfs_map_bio()
  - the RAID1 the missing device has to be at %dev_nr = 1
 In bbio_error()
  . before bbio_error() is called the bio of the not-missing
    device at %dev_nr = 0 must be completed so that the below
    condition is true
     if (atomic_dec_and_test(&bbio->stripes_pending)) {

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-10-30 12:28:01 +01:00
Anand Jain
de48373454 btrfs: use need_full_stripe() in __btrfs_map_block()
A cleanup patch, use need_full_stripe() to replace the open code.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Qu Wenruo <quwenruo.btrfs@gmx.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-10-30 12:28:01 +01:00
Anand Jain
2dbe0c7718 btrfs: use BLK_STS defines where needed
At few places we could use BLK_STS_OK and BLK_STS_NOSUPP.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Satoru Taekeuchi <satoru.takeuchi@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ dropped first hunk btrfs_endio_direct_read ]
Signed-off-by: David Sterba <dsterba@suse.com>
2017-10-30 12:28:01 +01:00
Anand Jain
2b902dfc89 btrfs: fix use of error or warning for missing device
When device is missing without the -o degraded option then its an error
so report it as an error instead of a warning.  And when -o degraded
option is provided, log the missing device as warning.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ switch error to bool ]
Signed-off-by: David Sterba <dsterba@suse.com>
2017-10-30 12:27:59 +01:00
Anand Jain
5a2b8e601c btrfs: declare btrfs_report_missing_device() static
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-10-30 12:27:59 +01:00