leandrof/linux
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
d201238ccd
linux/fs/btrfs
History
Qu Wenruo d201238ccd btrfs: repair super block num_devices automatically 
[BUG]
There is a report that a btrfs has a bad super block num devices.

This makes btrfs to reject the fs completely.

  BTRFS error (device sdd3): super_num_devices 3 mismatch with num_devices 2 found here
  BTRFS error (device sdd3): failed to read chunk tree: -22
  BTRFS error (device sdd3): open_ctree failed

[CAUSE]
During btrfs device removal, chunk tree and super block num devs are
updated in two different transactions:

  btrfs_rm_device()
  |- btrfs_rm_dev_item(device)
  |  |- trans = btrfs_start_transaction()
  |  |  Now we got transaction X
  |  |
  |  |- btrfs_del_item()
  |  |  Now device item is removed from chunk tree
  |  |
  |  |- btrfs_commit_transaction()
  |     Transaction X got committed, super num devs untouched,
  |     but device item removed from chunk tree.
  |     (AKA, super num devs is already incorrect)
  |
  |- cur_devices->num_devices--;
  |- cur_devices->total_devices--;
  |- btrfs_set_super_num_devices()
     All those operations are not in transaction X, thus it will
     only be written back to disk in next transaction.

So after the transaction X in btrfs_rm_dev_item() committed, but before
transaction X+1 (which can be minutes away), a power loss happen, then
we got the super num mismatch.

This has been fixed by commit bbac58698a ("btrfs: remove device item
and update super block in the same transaction").

[FIX]
Make the super_num_devices check less strict, converting it from a hard
error to a warning, and reset the value to a correct one for the current
or next transaction commit.

As the number of device items is the critical information where the
super block num_devices is only a cached value (and also useful for
cross checking), it's safe to automatically update it. Other device
related problems like missing device are handled after that and may
require other means to resolve, like degraded mount. With this fix,
potentially affected filesystems won't fail mount and require the manual
repair by btrfs check.

Reported-by: Luca Béla Palkovics <luca.bela.palkovics@gmail.com>
Link: https://lore.kernel.org/linux-btrfs/CA+8xDSpvdm_U0QLBAnrH=zqDq_cWCOH5TiV46CKmp3igr44okQ@mail.gmail.com/
CC: stable@vger.kernel.org # 4.14+
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2022-05-16 17:03:14 +02:00
..
tests btrfs: assert we have a write lock when removing and replacing extent maps 2022-03-14 13:13:50 +01:00
acl.c btrfs: reserve correct number of items for inode creation 2022-05-16 17:03:08 +02:00
async-thread.c btrfs: fix memory ordering between normal and ordered work functions 2021-11-16 16:50:23 +01:00
async-thread.h
backref.c btrfs: unify the error handling pattern for read_tree_block() 2022-03-14 13:13:53 +01:00
backref.h btrfs: remove ignore_offset argument from btrfs_find_all_roots() 2021-08-23 13:19:01 +02:00
block-group.c btrfs: avoid double search for block group during NOCOW writes 2022-05-16 17:03:13 +02:00
block-group.h btrfs: avoid double search for block group during NOCOW writes 2022-05-16 17:03:13 +02:00
block-rsv.c btrfs: reserve extra space for the free space tree 2022-01-07 14:18:25 +01:00
block-rsv.h btrfs: init root block_rsv at init root time 2022-01-03 15:09:48 +01:00
btrfs_inode.h btrfs: export a helper for compression hard check 2022-04-27 22:15:40 +02:00
check-integrity.c btrfs: check-integrity: simplify bio allocation in btrfsic_read_block 2022-05-16 17:03:12 +02:00
check-integrity.h btrfs: check-integrity: split submit_bio from btrfsic checking 2022-05-16 17:03:12 +02:00
compression.c btrfs: do not pass compressed_bio to submit_compressed_bio() 2022-05-16 17:03:13 +02:00
compression.h btrfs: track compressed bio errors as blk_status_t 2022-03-14 13:13:51 +01:00
ctree.c btrfs: tree-checker: check extent buffer owner against owner rootid 2022-05-16 17:03:09 +02:00
ctree.h btrfs: use a read/write lock for protecting the block groups tree 2022-05-16 17:03:13 +02:00
delalloc-space.c btrfs: avoid blocking on space revervation when doing nowait dio writes 2022-05-16 17:03:10 +02:00
delalloc-space.h
delayed-inode.c btrfs: add an inode-item.h 2022-01-07 14:18:23 +01:00
delayed-inode.h btrfs: make btrfs_delayed_update_inode take btrfs_inode 2020-12-08 15:54:10 +01:00
delayed-ref.c btrfs: reserve extra space for the free space tree 2022-01-07 14:18:25 +01:00
delayed-ref.h btrfs: make btrfs_ref::real_root optional 2021-10-26 19:08:06 +02:00
dev-replace.c btrfs: use a local variable for fs_devices pointer in btrfs_dev_replace_finishing 2022-05-16 17:03:08 +02:00
dev-replace.h btrfs: zoned: mark block groups to copy for device-replace 2021-02-09 02:46:07 +01:00
dir-item.c btrfs: use btrfs_for_each_slot in btrfs_search_dir_index_item 2022-05-16 17:03:07 +02:00
discard.c btrfs: fix typos in comments 2021-06-22 14:11:57 +02:00
discard.h btrfs: cleanup btrfs_discard_update_discardable usage 2020-12-08 15:54:02 +01:00
disk-io.c btrfs: use a read/write lock for protecting the block groups tree 2022-05-16 17:03:13 +02:00
disk-io.h btrfs: remove trivial wrapper btrfs_read_buffer() 2022-05-16 17:03:07 +02:00
export.c btrfs: locking: rip out path->leave_spinning 2020-12-08 15:54:02 +01:00
export.h
extent_io.c btrfs: return correct error number for __extent_writepage_io() 2022-05-16 17:03:13 +02:00
extent_io.h btrfs: avoid double clean up when submit_one_bio() failed 2022-05-16 17:03:13 +02:00
extent_map.c btrfs: assert we have a write lock when removing and replacing extent maps 2022-03-14 13:13:50 +01:00
extent_map.h btrfs: defrag: don't use merged extent map for their generation check 2022-02-23 17:43:13 +01:00
extent-io-tree.h btrfs: Convert from invalidatepage to invalidate_folio 2022-03-15 08:23:29 -04:00
extent-tree.c btrfs: use a read/write lock for protecting the block groups tree 2022-05-16 17:03:13 +02:00
file-item.c btrfs: handle csum lookup errors properly on reads 2022-03-14 13:13:51 +01:00
file.c btrfs: avoid blocking on space revervation when doing nowait dio writes 2022-05-16 17:03:10 +02:00
free-space-cache.c btrfs: use rbtree with leftmost node cached for tracking lowest block group 2022-05-16 17:03:13 +02:00
free-space-cache.h btrfs: change name and type of private member of btrfs_free_space_ctl 2022-01-03 15:09:50 +01:00
free-space-tree.c btrfs: use rbtree with leftmost node cached for tracking lowest block group 2022-05-16 17:03:13 +02:00
free-space-tree.h
inode-item.c btrfs: make should_throttle loop local in btrfs_truncate_inode_items 2022-01-07 14:18:25 +01:00
inode-item.h btrfs: add inode to truncate control 2022-01-07 14:18:24 +01:00
inode.c btrfs: avoid double search for block group during NOCOW writes 2022-05-16 17:03:13 +02:00
ioctl.c btrfs: remove unnecessary type casts 2022-05-16 17:03:11 +02:00
Kconfig btrfs: use generic Kconfig option for 256kB page size limit 2022-01-20 08:52:55 +02:00
locking.c btrfs: fix typos in comments 2021-06-22 14:11:57 +02:00
locking.h btrfs: assert that extent buffers are write locked instead of only locked 2021-10-26 19:08:02 +02:00
lzo.c btrfs: add lzo workspace buffer length constants 2022-03-14 13:13:50 +01:00
Makefile Kbuild: add -Wno-shift-negative-value where -Wextra is used 2022-03-13 17:30:31 +09:00
misc.h btrfs: use correct header for div_u64 in misc.h 2021-09-07 14:29:50 +02:00
ordered-data.c btrfs: add BTRFS_IOC_ENCODED_WRITE 2022-03-14 13:13:51 +01:00
ordered-data.h btrfs: add BTRFS_IOC_ENCODED_WRITE 2022-03-14 13:13:51 +01:00
orphan.c
print-tree.c btrfs: unify the error handling pattern for read_tree_block() 2022-03-14 13:13:53 +01:00
print-tree.h btrfs: print the actual offset in btrfs_root_name 2021-01-07 17:25:05 +01:00
props.c btrfs: move common inode creation code into btrfs_create_new_inode() 2022-05-16 17:03:08 +02:00
props.h btrfs: move common inode creation code into btrfs_create_new_inode() 2022-05-16 17:03:08 +02:00
qgroup.c btrfs: avoid blocking on space revervation when doing nowait dio writes 2022-05-16 17:03:10 +02:00
qgroup.h btrfs: avoid blocking on space revervation when doing nowait dio writes 2022-05-16 17:03:10 +02:00
raid56.c btrfs: stop using the btrfs_bio saved iter in index_rbio_pages 2022-05-16 17:03:12 +02:00
raid56.h btrfs: remove btrfs_raid_bio::fs_info member 2021-10-26 19:08:03 +02:00
rcu-string.h
ref-verify.c btrfs: stop accessing ->extent_root directly 2022-01-03 15:09:49 +01:00
ref-verify.h
reflink.c btrfs: add and use helper to assert an inode range is clean 2022-05-16 17:03:09 +02:00
reflink.h
relocation.c btrfs: remove unnecessary check of iput argument 2022-05-16 17:03:12 +02:00
root-tree.c btrfs: avoid blocking on space revervation when doing nowait dio writes 2022-05-16 17:03:10 +02:00
scrub.c btrfs: don't allocate a btrfs_bio for scrub bios 2022-05-16 17:03:12 +02:00
send.c btrfs: use btrfs_for_each_slot in btrfs_unlink_all_paths 2022-05-16 17:03:08 +02:00
send.h btrfs: reuse existing inode from btrfs_ioctl 2022-03-14 13:13:46 +01:00
space-info.c btrfs: make the bg_reclaim_threshold per-space info 2022-05-16 17:03:11 +02:00
space-info.h btrfs: make the bg_reclaim_threshold per-space info 2022-05-16 17:03:11 +02:00
struct-funcs.c btrfs: add special case to setget helpers for 64k pages 2021-08-23 13:18:58 +02:00
subpage.c btrfs: remove unnecessary type casts 2022-05-16 17:03:11 +02:00
subpage.h btrfs: make nodesize >= PAGE_SIZE case to reuse the non-subpage routine 2022-05-16 17:03:11 +02:00
super.c btrfs: add messages to printk index 2022-05-16 17:03:09 +02:00
sysfs.c btrfs: change the bg_reclaim_threshold valid region from 0 to 100 2022-05-16 17:03:11 +02:00
sysfs.h btrfs: split and refactor btrfs_sysfs_remove_devices_dir 2020-10-07 12:12:21 +02:00
transaction.c btrfs: use a read/write lock for protecting the block groups tree 2022-05-16 17:03:13 +02:00
transaction.h btrfs: pass btrfs_fs_info for deleting snapshots and cleaner 2022-03-14 13:13:52 +01:00
tree-checker.c btrfs: tree-checker: check extent buffer owner against owner rootid 2022-05-16 17:03:09 +02:00
tree-checker.h btrfs: tree-checker: check extent buffer owner against owner rootid 2022-05-16 17:03:09 +02:00
tree-defrag.c btrfs: remove unnecessary extent root check in btrfs_defrag_leaves 2022-01-03 15:09:48 +01:00
tree-log.c btrfs: remove unnecessary check of iput argument 2022-05-16 17:03:12 +02:00
tree-log.h btrfs: avoid inode logging during rename and link when possible 2022-03-14 13:13:48 +01:00
tree-mod-log.c btrfs: fix race when picking most recent mod log operation for an old root 2021-04-20 19:27:17 +02:00
tree-mod-log.h btrfs: add and use helper to get lowest sequence number for the tree mod log 2021-04-19 17:25:17 +02:00
ulist.c
ulist.h
uuid-tree.c btrfs: drop the _nr from the item helpers 2022-01-03 15:09:43 +01:00
verity.c btrfs: drop the _nr from the item helpers 2022-01-03 15:09:43 +01:00
volumes.c btrfs: repair super block num_devices automatically 2022-05-16 17:03:14 +02:00
volumes.h btrfs: fix direct I/O read repair for split bios 2022-04-19 15:44:56 +02:00
xattr.c btrfs: use btrfs_for_each_slot in btrfs_listxattr 2022-05-16 17:03:08 +02:00
xattr.h
zlib.c Revert "btrfs: compression: drop kmap/kunmap from zlib" 2021-10-29 13:03:05 +02:00
zoned.c btrfs: zoned: make auto-reclaim less aggressive 2022-05-16 17:03:11 +02:00
zoned.h btrfs: zoned: make auto-reclaim less aggressive 2022-05-16 17:03:11 +02:00
zstd.c btrfs: use non-bh spin_lock in zstd timer callback 2022-05-16 17:03:13 +02:00