Commit Graph

287 Commits

Author SHA1 Message Date
Liu Bo ed5d5f37e6 Btrfs: dev-replace: skip prealloc extents when copy nocow pages
It doens't make sense to process prealloc extents as pages will be
filled with zero when reading prealloc extents.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-26 15:09:40 +02:00
Anand Jain 7ef2d6a722 btrfs: not a disk error if the bio_add_page fails
bio_add_page() can fail for logical reasons as from the bio_add_page()
comments:

/*
 * This will only fail if either bio->bi_vcnt == bio->bi_max_vecs or
 * it's a cloned bio.
 */

Here we have just allocated the bio, so both of those failures can't
occur. So drop the check. We can also drop the error stats for write
error.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2018-03-26 15:09:36 +02:00
Anand Jain cadbc0a067 btrfs: rename btrfs_device::scrub_device to scrub_ctx
btrfs_device::scrub_device is not a device which is being scrubbed,
but it holds the scrub context, so rename to reflect the same. No
functional changes here.

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 762221f095 Btrfs: fix scrub to repair raid6 corruption
The raid6 corruption is that,
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.

We've fixed normal reads to rebuild raid6 correctly with more retries
in Patch "Btrfs: make raid6 rebuild retry more"[1], this is to fix
scrub to do the exactly same rebuild process.

[1]: https://patchwork.kernel.org/patch/10091755/

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
David Sterba e43bbe5e16 btrfs: sink unlock_extent parameter gfp_flags
All callers pass either GFP_NOFS or GFP_KERNEL now, so we can sink the
parameter to the function, though we lose some of the slightly better
semantics of GFP_KERNEL in some places, it's worth cleaning up the
callchains.

Signed-off-by: David Sterba <dsterba@suse.com>
2018-01-22 16:08:19 +01:00
Liu Bo b4ff5ad72e Btrfs: use struct completion in scrub_submit_raid56_bio_wait
This changes to use struct completion directly and removes 'struct
scrub_bio_ret' along with the code using it.

This struct is used to get the return value from bio, but the caller can
access bio to get the return value directly and is holding a reference
on it so it won't go away underneath us and can be removed safely.

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>
2018-01-22 16:08:15 +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
Zygo Blaxell c995ab3cda btrfs: add a flag to iterate_inodes_from_logical to find all extent refs for uncompressed extents
The LOGICAL_INO ioctl provides a backward mapping from extent bytenr and
offset (encoded as a single logical address) to a list of extent refs.
LOGICAL_INO complements TREE_SEARCH, which provides the forward mapping
(extent ref -> extent bytenr and offset, or logical address).  These are
useful capabilities for programs that manipulate extents and extent
references from userspace (e.g. dedup and defrag utilities).

When the extents are uncompressed (and not encrypted and not other),
check_extent_in_eb performs filtering of the extent refs to remove any
extent refs which do not contain the same extent offset as the 'logical'
parameter's extent offset.  This prevents LOGICAL_INO from returning
references to more than a single block.

To find the set of extent references to an uncompressed extent from [a, b),
userspace has to run a loop like this pseudocode:

	for (i = a; i < b; ++i)
		extent_ref_set += LOGICAL_INO(i);

At each iteration of the loop (up to 32768 iterations for a 128M extent),
data we are interested in is collected in the kernel, then deleted by
the filter in check_extent_in_eb.

When the extents are compressed (or encrypted or other), the 'logical'
parameter must be an extent bytenr (the 'a' parameter in the loop).
No filtering by extent offset is done (or possible?) so the result is
the complete set of extent refs for the entire extent.  This removes
the need for the loop, since we get all the extent refs in one call.

Add an 'ignore_offset' argument to iterate_inodes_from_logical,
[...several levels of function call graph...], and check_extent_in_eb, so
that we can disable the extent offset filtering for uncompressed extents.
This flag can be set by an improved version of the LOGICAL_INO ioctl to
get either behavior as desired.

There is no functional change in this patch.  The new flag is always
false.

Signed-off-by: Zygo Blaxell <ce3g8jdj@umail.furryterror.org>
Reviewed-by: David Sterba <dsterba@suse.com>
[ minor coding style fixes ]
Signed-off-by: David Sterba <dsterba@suse.com>
2017-11-01 20:45:34 +01:00
David Sterba 6aa21263e3 btrfs: scrub: get rid of sector_t
The use of sector_t is not necessry, it's just for a warning.  Switch to
u64 and rename the variable and use byte units instead of 512b, ie.
dropping the >> 9 shifts.  The messages are adjusted as well.

Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-10-30 12:28:00 +01:00
Linus Torvalds 66ba772ee3 Merge branch 'for-4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs updates from David Sterba:
 "The changes range through all types: cleanups, core chagnes, sanity
  checks, fixes, other user visible changes, detailed list below:

   - deprecated: user transaction ioctl

   - mount option ssd does not change allocation alignments

   - degraded read-write mount is allowed if all the raid profile
     constraints are met, now based on more accurate check

   - defrag: do not reset compression afterwards; the NOCOMPRESS flag
     can be now overriden by defrag

   - prep work for better extent reference tracking (related to the
     qgroup slowness with balance)

   - prep work for compression heuristics

   - memory allocation reductions (may help latencies on a loaded
     system)

   - better accounting for io waiting states

   - error handling improvements (removed BUGs)

   - added more sanity checks for shared refs

   - fix readdir vs pagefault deadlock under some circumstances

   - fix for 'no-hole' mode, certain combination of compressed and
     inline extents

   - send: fix emission of invalid clone operations

   - fixup file mode if setting acls fail

   - more fixes from fuzzing

   - oher cleanups"

* 'for-4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: (104 commits)
  btrfs: submit superblock io with REQ_META and REQ_PRIO
  btrfs: remove unnecessary memory barrier in btrfs_direct_IO
  btrfs: remove superfluous chunk_tree argument from btrfs_alloc_dev_extent
  btrfs: Remove chunk_objectid parameter of btrfs_alloc_dev_extent
  btrfs: pass fs_info to btrfs_del_root instead of tree_root
  Btrfs: add one more sanity check for shared ref type
  Btrfs: remove BUG_ON in __add_tree_block
  Btrfs: remove BUG() in add_data_reference
  Btrfs: remove BUG() in print_extent_item
  Btrfs: remove BUG() in btrfs_extent_inline_ref_size
  Btrfs: convert to use btrfs_get_extent_inline_ref_type
  Btrfs: add a helper to retrive extent inline ref type
  btrfs: scrub: simplify scrub worker initialization
  btrfs: scrub: clean up division in scrub_find_csum
  btrfs: scrub: clean up division in __scrub_mark_bitmap
  btrfs: scrub: use bool for flush_all_writes
  btrfs: preserve i_mode if __btrfs_set_acl() fails
  btrfs: Remove extraneous chunk_objectid variable
  btrfs: Remove chunk_objectid argument from btrfs_make_block_group
  btrfs: Remove extra parentheses from condition in copy_items()
  ...
2017-09-09 13:27:51 -07:00
Christoph Hellwig 74d46992e0 block: replace bi_bdev with a gendisk pointer and partitions index
This way we don't need a block_device structure to submit I/O.  The
block_device has different life time rules from the gendisk and
request_queue and is usually only available when the block device node
is open.  Other callers need to explicitly create one (e.g. the lightnvm
passthrough code, or the new nvme multipathing code).

For the actual I/O path all that we need is the gendisk, which exists
once per block device.  But given that the block layer also does
partition remapping we additionally need a partition index, which is
used for said remapping in generic_make_request.

Note that all the block drivers generally want request_queue or
sometimes the gendisk, so this removes a layer of indirection all
over the stack.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-23 12:49:55 -06:00
David Sterba af1cbe0a66 btrfs: scrub: simplify scrub worker initialization
Minor simplification, merge calls to one.

Signed-off-by: David Sterba <dsterba@suse.com>
2017-08-21 17:47:42 +02:00
David Sterba 1d1bf92d9d btrfs: scrub: clean up division in scrub_find_csum
Use proper helpers for 64bit division.

Signed-off-by: David Sterba <dsterba@suse.com>
2017-08-21 17:47:42 +02:00
David Sterba 7736b0a431 btrfs: scrub: clean up division in __scrub_mark_bitmap
Use proper helpers for 64bit division and then cast to narrower type.

Signed-off-by: David Sterba <dsterba@suse.com>
2017-08-21 17:47:42 +02:00
David Sterba 2073c4c2e5 btrfs: scrub: use bool for flush_all_writes
flush_all_writes is an atomic but does not use the semantics at all,
it's just on/off indicator, we can use bool.

Signed-off-by: David Sterba <dsterba@suse.com>
2017-08-21 17:47:42 +02:00
Anand Jain 44880fdc91 btrfs: use appropriate define for the fsid
Though BTRFS_FSID_SIZE and BTRFS_UUID_SIZE are of the same size, we
should use the matching constant for the fsid buffer.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-08-18 16:36:29 +02:00
David Sterba 131ce4367a btrfs: account that we're waiting for IO in scrub_submit_raid56_bio_wait
Correctly account for IO when waiting for a submitted bio in scrub. This
only for the accounting purposes and should not change other behaviour.

Signed-off-by: David Sterba <dsterba@suse.com>
2017-08-16 16:12:04 +02:00
David Sterba 913e153572 btrfs: drop newlines from strings when using btrfs_* helpers
The helpers append "\n" so we can keep the actual strings shorter. The
extra newline will print an empty line.  Some messages have been
slightly modified to be more consistent with the rest (lowercase first
letter).

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-08-16 16:12:02 +02:00
Linus Torvalds 8c27cb3566 Merge branch 'for-4.13-part1' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs updates from David Sterba:
 "The core updates improve error handling (mostly related to bios), with
  the usual incremental work on the GFP_NOFS (mis)use removal,
  refactoring or cleanups. Except the two top patches, all have been in
  for-next for an extensive amount of time.

  User visible changes:

   - statx support

   - quota override tunable

   - improved compression thresholds

   - obsoleted mount option alloc_start

  Core updates:

   - bio-related updates:
       - faster bio cloning
       - no allocation failures
       - preallocated flush bios

   - more kvzalloc use, memalloc_nofs protections, GFP_NOFS updates

   - prep work for btree_inode removal

   - dir-item validation

   - qgoup fixes and updates

   - cleanups:
       - removed unused struct members, unused code, refactoring
       - argument refactoring (fs_info/root, caller -> callee sink)
       - SEARCH_TREE ioctl docs"

* 'for-4.13-part1' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: (115 commits)
  btrfs: Remove false alert when fiemap range is smaller than on-disk extent
  btrfs: Don't clear SGID when inheriting ACLs
  btrfs: fix integer overflow in calc_reclaim_items_nr
  btrfs: scrub: fix target device intialization while setting up scrub context
  btrfs: qgroup: Fix qgroup reserved space underflow by only freeing reserved ranges
  btrfs: qgroup: Introduce extent changeset for qgroup reserve functions
  btrfs: qgroup: Fix qgroup reserved space underflow caused by buffered write and quotas being enabled
  btrfs: qgroup: Return actually freed bytes for qgroup release or free data
  btrfs: qgroup: Cleanup btrfs_qgroup_prepare_account_extents function
  btrfs: qgroup: Add quick exit for non-fs extents
  Btrfs: rework delayed ref total_bytes_pinned accounting
  Btrfs: return old and new total ref mods when adding delayed refs
  Btrfs: always account pinned bytes when dropping a tree block ref
  Btrfs: update total_bytes_pinned when pinning down extents
  Btrfs: make BUG_ON() in add_pinned_bytes() an ASSERT()
  Btrfs: make add_pinned_bytes() take an s64 num_bytes instead of u64
  btrfs: fix validation of XATTR_ITEM dir items
  btrfs: Verify dir_item in iterate_object_props
  btrfs: Check name_len before in btrfs_del_root_ref
  btrfs: Check name_len before reading btrfs_get_name
  ...
2017-07-05 16:41:23 -07:00
Chris Mason 6374e57ad8 btrfs: fix integer overflow in calc_reclaim_items_nr
Dave Jones hit a WARN_ON(nr < 0) in btrfs_wait_ordered_roots() with
v4.12-rc6.  This was because commit 70e7af244 made it possible for
calc_reclaim_items_nr() to return a negative number.  It's not really a
bug in that commit, it just didn't go far enough down the stack to find
all the possible 64->32 bit overflows.

This switches calc_reclaim_items_nr() to return a u64 and changes everyone
that uses the results of that math to u64 as well.

Reported-by: Dave Jones <davej@codemonkey.org.uk>
Fixes: 70e7af2 ("Btrfs: fix delalloc accounting leak caused by u32 overflow")
Signed-off-by: Chris Mason <clm@fb.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-29 20:17:02 +02:00
David Sterba ded56184a5 btrfs: scrub: fix target device intialization while setting up scrub context
The commit "btrfs: scrub: inline helper scrub_setup_wr_ctx" inlined a
helper but wrongly sets up the target device. Incidentally there's a
local variable with the same name as a parameter in the previous
function, so this got caught during runtime as crash in test btrfs/027.

Reported-by: Chris Mason <clm@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-29 20:17:02 +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 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 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 3fb99303c6 btrfs: scrub: embed scrub_wr_ctx into scrub context
The structure scrub_wr_ctx is not used anywhere just the scrub context,
we can move the members there. The tgtdev is renamed so it's more clear
that it belongs to the "wr" part.

Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-19 18:26:01 +02:00
David Sterba 25cc1226c1 btrfs: scrub: use fs_info::sectorsize and drop it from scrub context
As we now have the node/block sizes in fs_info, we can use them and can
drop the local copies.

Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-19 18:26:01 +02:00
David Sterba 4e2814ef04 btrfs: scrub: simplify cleanup of wr_ctx in scrub_free_ctx
We don't need to take the mutex and zero out wr_cur_bio, as this is
called after the scrub finished.

Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-19 18:26:00 +02:00
David Sterba e241ddeb9c btrfs: scrub: inline helper scrub_free_wr_ctx
The helper scrub_free_wr_ctx is used only once and fits into
scrub_free_ctx as it continues sctx shutdown, no need to keep it
separate.

Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-19 18:26:00 +02:00
David Sterba 8fcdac3f20 btrfs: scrub: inline helper scrub_setup_wr_ctx
The helper scrub_setup_wr_ctx is used only once and fits into
scrub_setup_ctx as it continues intialization, no need to keep it
separate.

Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-19 18:26:00 +02:00
Josef Bacik 6ec656bc0f btrfs: remove inode argument from repair_io_failure
Once we remove the btree_inode we won't have an inode to pass anymore,
just pass the fs_info directly and the inum since we use that to print
out the repair message.

Signed-off-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-06-19 18:25:58 +02:00
Christoph Hellwig 4e4cbee93d block: switch bios to blk_status_t
Replace bi_error with a new bi_status to allow for a clear conversion.
Note that device mapper overloaded bi_error with a private value, which
we'll have to keep arround at least for now and thus propagate to a
proper blk_status_t value.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-06-09 09:27:32 -06:00
Qu Wenruo 28d70e237d btrfs: scrub: Fix RAID56 recovery race condition
When scrubbing a RAID5 which has recoverable data corruption (only one
data stripe is corrupted), sometimes scrub will report more csum errors
than expected. Sometimes even unrecoverable error will be reported.

The problem can be easily reproduced by the following steps:
1) Create a btrfs with RAID5 data profile with 3 devs
2) Mount it with nospace_cache or space_cache=v2
   To avoid extra data space usage.
3) Create a 128K file and sync the fs, unmount it
   Now the 128K file lies at the beginning of the data chunk
4) Locate the physical bytenr of data chunk on dev3
   Dev3 is the 1st data stripe.
5) Corrupt the first 64K of the data chunk stripe on dev3
6) Mount the fs and scrub it

The correct csum error number should be 16 (assuming using x86_64).
Larger csum error number can be reported in a 1/3 chance.
And unrecoverable error can also be reported in a 1/10 chance.

The root cause of the problem is RAID5/6 recover code has race
condition, due to the fact that full scrub is initiated per device.

While for other mirror based profiles, each mirror is independent with
each other, so race won't cause any big problem.

For example:
        Corrupted       |       Correct          |      Correct        |
|   Scrub dev3 (D1)     |    Scrub dev2 (D2)     |    Scrub dev1(P)    |
------------------------------------------------------------------------
Read out D1             |Read out D2             |Read full stripe     |
Check csum              |Check csum              |Check parity         |
Csum mismatch           |Csum match, continue    |Parity mismatch      |
handle_errored_block    |                        |handle_errored_block |
 Read out full stripe   |                        | Read out full stripe|
 D1 csum error(err++)   |                        | D1 csum error(err++)|
 Recover D1             |                        | Recover D1          |

So D1's csum error is accounted twice, just because
handle_errored_block() doesn't have enough protection, and race can happen.

On even worse case, for example D1's recovery code is re-writing
D1/D2/P, and P's recovery code is just reading out full stripe, then we
can cause unrecoverable error.

This patch will use previously introduced lock_full_stripe() and
unlock_full_stripe() to protect the whole scrub_handle_errored_block()
function for RAID56 recovery.
So no extra csum error nor unrecoverable error.

Reported-by: Goffredo Baroncelli <kreijack@libero.it>
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-04-18 14:07:27 +02:00
Qu Wenruo 0966a7b130 btrfs: scrub: Introduce full stripe lock for RAID56
Unlike mirror based profiles, RAID5/6 recovery needs to read out the
whole full stripe.

And if we don't do proper protection, it can easily cause race condition.

Introduce 2 new functions: lock_full_stripe() and unlock_full_stripe()
for RAID5/6.
Which store a rb_tree of mutexes for full stripes, so scrub callers can
use them to lock a full stripe to avoid race.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ minor comment adjustments ]
Signed-off-by: David Sterba <dsterba@suse.com>
2017-04-18 14:07:27 +02:00
Liu Bo 42c61ab676 Btrfs: switch to div64_u64 if with a u64 divisor
This is fixing code pieces where we use div_u64 when passing a u64 divisor.

Cc: David Sterba <dsterba@suse.cz>
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>
2017-04-18 14:07:26 +02:00
Liu Bo 972d721939 Btrfs: update scrub_parity to use u64 stripe_len
Commit 3d8da67817 ("Btrfs: fix divide error upon chunk's stripe_len")
changed stripe_len in struct map_lookup to u64, but didn't update
stripe_len in struct scrub_parity.

This updates the type and switches to div64_u64_rem to match u64 divisor.

Cc: David Sterba <dsterba@suse.cz>
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>
2017-04-18 14:07:26 +02:00
David Sterba 619a974292 btrfs: use clear_page where appropriate
There's a helper to clear whole page, with a arch-specific optimized
code. The replaced cases do not seem to be in performace critical code,
but we still might get some percent gain.

Signed-off-by: David Sterba <dsterba@suse.com>
2017-04-18 14:07:26 +02:00
Qu Wenruo e501bfe323 btrfs: Prevent scrub recheck from racing with dev replace
scrub_setup_recheck_block() calls btrfs_map_sblock() and then accesses
bbio without protection of bio_counter.

This can lead to use-after-free if racing with dev replace cancel.

Fix it by increasing bio_counter before calling btrfs_map_sblock() and
decreasing the bio_counter when corresponding recover is finished.

Cc: Liu Bo <bo.li.liu@oracle.com>
Reported-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-04-18 14:07:26 +02:00
Qu Wenruo ae6529c35b btrfs: Wait for in-flight bios before freeing target device for raid56
When raid56 dev-replace is cancelled by running scrub, we will free
target device without waiting for in-flight bios, causing the following
NULL pointer deference or general protection failure.

 BUG: unable to handle kernel NULL pointer dereference at 00000000000005e0
 IP: generic_make_request_checks+0x4d/0x610
 CPU: 1 PID: 11676 Comm: kworker/u4:14 Tainted: G  O    4.11.0-rc2 #72
 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.10.2-20170228_101828-anatol 04/01/2014
 Workqueue: btrfs-endio-raid56 btrfs_endio_raid56_helper [btrfs]
 task: ffff88002875b4c0 task.stack: ffffc90001334000
 RIP: 0010:generic_make_request_checks+0x4d/0x610
 Call Trace:
  ? generic_make_request+0xc7/0x360
  generic_make_request+0x24/0x360
  ? generic_make_request+0xc7/0x360
  submit_bio+0x64/0x120
  ? page_in_rbio+0x4d/0x80 [btrfs]
  ? rbio_orig_end_io+0x80/0x80 [btrfs]
  finish_rmw+0x3f4/0x540 [btrfs]
  validate_rbio_for_rmw+0x36/0x40 [btrfs]
  raid_rmw_end_io+0x7a/0x90 [btrfs]
  bio_endio+0x56/0x60
  end_workqueue_fn+0x3c/0x40 [btrfs]
  btrfs_scrubparity_helper+0xef/0x620 [btrfs]
  btrfs_endio_raid56_helper+0xe/0x10 [btrfs]
  process_one_work+0x2af/0x720
  ? process_one_work+0x22b/0x720
  worker_thread+0x4b/0x4f0
  kthread+0x10f/0x150
  ? process_one_work+0x720/0x720
  ? kthread_create_on_node+0x40/0x40
  ret_from_fork+0x2e/0x40
 RIP: generic_make_request_checks+0x4d/0x610 RSP: ffffc90001337bb8

In btrfs_dev_replace_finishing(), we will call
btrfs_rm_dev_replace_blocked() to wait bios before destroying the target
device when scrub is finished normally.

However when dev-replace is aborted, either due to error or cancelled by
scrub, we didn't wait for bios, this can lead to use-after-free if there
are bios holding the target device.

Furthermore, for raid56 scrub, at least 2 places are calling
btrfs_map_sblock() without protection of bio_counter, leading to the
problem.

This patch fixes the problem:
1) Wait for bio_counter before freeing target device when canceling
   replace
2) When calling btrfs_map_sblock() for raid56, use bio_counter to
   protect the call.

Cc: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-04-18 14:07:26 +02:00
Qu Wenruo 9a33944bdf btrfs: scrub: Don't append on-disk pages for raid56 scrub
In the following situation, scrub will calculate wrong parity to
overwrite the correct one:

RAID5 full stripe:

Before
|     Dev 1      |     Dev  2     |     Dev 3     |
| Data stripe 1  | Data stripe 2  | Parity Stripe |
--------------------------------------------------- 0
| 0x0000 (Bad)   |     0xcdcd     |     0x0000    |
--------------------------------------------------- 4K
|     0xcdcd     |     0xcdcd     |     0x0000    |
...
|     0xcdcd     |     0xcdcd     |     0x0000    |
--------------------------------------------------- 64K

After scrubbing dev3 only:

|     Dev 1      |     Dev  2     |     Dev 3     |
| Data stripe 1  | Data stripe 2  | Parity Stripe |
--------------------------------------------------- 0
| 0xcdcd (Good)  |     0xcdcd     | 0xcdcd (Bad)  |
--------------------------------------------------- 4K
|     0xcdcd     |     0xcdcd     |     0x0000    |
...
|     0xcdcd     |     0xcdcd     |     0x0000    |
--------------------------------------------------- 64K

The reason is that after raid56 read rebuild rbio->stripe_pages are all
correctly recovered (0xcd for data stripes).

However when we check and repair parity in
scrub_parity_check_and_repair(), we will append pages in sparity->spages
list to rbio->bio_pages[], which contains old on-disk data.

And when we submit parity data to disk, we calculate parity using
rbio->bio_pages[] first, if rbio->bio_pages[] not found, then fallback
to rbio->stripe_pages[].

The patch fix it by not appending pages from sparity->spages.
So finish_parity_scrub() will use rbio->stripe_pages[] which is correct.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-04-18 14:07:26 +02:00
David Sterba 825ad4c964 btrfs: drop redundant parameters from btrfs_map_sblock
All callers pass 0 for mirror_num and 1 for need_raid_map.

Signed-off-by: David Sterba <dsterba@suse.com>
2017-04-18 14:07:26 +02:00
Liu Bo 1bcd7aa17f Btrfs: set scrub page's io_error if failing to submit io
Scrub repairs data by the unit called scrub_block, which may contain
several pages.  Scrub always tries to look up a good copy of a whole
block, but if there's no such copy, it tries to do repair page by page.

If we don't set page's io_error when checking this bad copy, in the last
step, we may skip this page when repairing bad copy from good copy.

Cc: David Sterba <dsterba@suse.cz>
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>
2017-04-18 14:07:26 +02:00
Elena Reshetova 99f4cdb16f btrfs: convert scrub_ctx.refs from atomic_t to refcount_t
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.

Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-04-18 14:07:24 +02:00
Elena Reshetova 78a764504d btrfs: convert scrub_parity.refs from atomic_t to refcount_t
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.

Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-04-18 14:07:24 +02:00
Elena Reshetova 186debd6ed btrfs: convert scrub_block.refs from atomic_t to refcount_t
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.

Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-04-18 14:07:24 +02:00
Elena Reshetova 6f615018b3 btrfs: convert scrub_recover.refs from atomic_t to refcount_t
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.

Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-04-18 14:07:24 +02:00
Nikolay Borisov 1c8c9c5216 btrfs: Make check_extent_to_block take btrfs_inode
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-02-28 11:30:11 +01:00
Nikolay Borisov 9d4f7f8ad6 btrfs: make repair_io_failure take btrfs_inode
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-02-28 11:30:09 +01:00