linux/fs/btrfs
Gui Hecheng 321592427c btrfs: fix dead lock while running replace and defrag concurrently
This can be reproduced by fstests: btrfs/070

The scenario is like the following:

replace worker thread		defrag thread
---------------------		-------------
copy_nocow_pages_worker		btrfs_defrag_file
  copy_nocow_pages_for_inode	    ...
				  btrfs_writepages
  |A| lock_extent_bits		    extent_write_cache_pages
				|B|   lock_page
					__extent_writepage
		...			  writepage_delalloc
					    find_lock_delalloc_range
				|B| 	      lock_extent_bits
  find_or_create_page
    pagecache_get_page
  |A| lock_page

This leads to an ABBA pattern deadlock. To fix it,
o we just change it to an AABB pattern which means to @unlock_extent_bits()
  before we @lock_page(), and in this way the @extent_read_full_page_nolock()
  is no longer in an locked context, so change it back to @extent_read_full_page()
  to regain protection.

o Since we @unlock_extent_bits() earlier, then before @write_page_nocow(),
  the extent may not really point at the physical block we want, so we
  have to check it before write.

Signed-off-by: Gui Hecheng <guihc.fnst@cn.fujitsu.com>
Tested-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2014-11-20 17:20:08 -08:00
..
tests Btrfs: remove empty block groups automatically 2014-09-22 17:13:21 -07:00
acl.c btrfs: remove useless ACL check 2014-06-09 17:20:42 -07:00
async-thread.c btrfs: remove unlikely from NULL checks 2014-10-02 16:06:19 +02:00
async-thread.h Btrfs: implement repair function when direct read fails 2014-09-17 13:39:01 -07:00
backref.c btrfs: remove parameter blocksize from read_tree_block 2014-10-02 17:14:50 +02:00
backref.h Btrfs: make fiemap not blow when you have lots of snapshots 2014-09-17 13:38:24 -07:00
btrfs_inode.h Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs 2014-10-11 08:03:52 -04:00
check-integrity.c Btrfs: check-int: don't complain about balanced blocks 2014-11-20 17:14:30 -08:00
check-integrity.h block: submit_bio_wait() conversions 2013-11-24 16:33:41 -07:00
compression.c Btrfs: don't ignore compressed bio write errors 2014-11-20 17:14:26 -08:00
compression.h btrfs: make static code static & remove dead code 2013-05-06 15:55:23 -04:00
ctree.c Btrfs: make xattr replace operations atomic 2014-11-20 17:20:07 -08:00
ctree.h Btrfs: make xattr replace operations atomic 2014-11-20 17:20:07 -08:00
delayed-inode.c btrfs: kill the key type accessor helpers 2014-09-17 13:37:12 -07:00
delayed-inode.h Btrfs: introduce the delayed inode ref deletion for the single link inode 2014-01-28 13:20:09 -08:00
delayed-ref.c Btrfs: rework qgroup accounting 2014-06-09 17:20:48 -07:00
delayed-ref.h Btrfs: rework qgroup accounting 2014-06-09 17:20:48 -07:00
dev-replace.c Btrfs: return failure if btrfs_dev_replace_finishing() failed 2014-11-20 17:14:28 -08:00
dev-replace.h Btrfs: add new sources for device replace code 2012-12-12 17:15:41 -05:00
dir-item.c Btrfs: make xattr replace operations atomic 2014-11-20 17:20:07 -08:00
disk-io.c btrfs: fix typos in btrfs_check_super_valid 2014-11-20 17:20:03 -08:00
disk-io.h Merge branch 'cleanup/blocksize-diet-part1' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux into for-linus 2014-10-04 09:57:14 -07:00
export.c btrfs: kill the key type accessor helpers 2014-09-17 13:37:12 -07:00
export.h
extent_io.c Btrfs: avoid premature -ENOMEM in clear_extent_bit() 2014-11-20 17:20:06 -08:00
extent_io.h Btrfs: set page and mapping error on compressed write failure 2014-11-20 17:14:25 -08:00
extent_map.c Btrfs: fix NULL pointer crash when running balance and scrub concurrently 2014-06-19 14:20:55 -07:00
extent_map.h Btrfs: fix NULL pointer crash when running balance and scrub concurrently 2014-06-19 14:20:55 -07:00
extent-tree.c Btrfs: move read only block groups onto their own list V2 2014-11-20 17:20:04 -08:00
file-item.c Btrfs: fix kfree on list_head in btrfs_lookup_csums_range error cleanup 2014-11-04 06:59:04 -08:00
file.c Btrfs: add helper btrfs_fdatawrite_range 2014-11-20 17:14:28 -08:00
free-space-cache.c Btrfs: improve free space cache management and space allocation 2014-09-17 13:38:13 -07:00
free-space-cache.h Btrfs: remove path arg from btrfs_truncate_free_space_cache 2013-11-11 21:51:33 -05:00
hash.c btrfs: LLVMLinux: Remove VLAIS 2014-10-14 10:51:22 +02:00
hash.h Btrfs: fix btrfs boot when compiled as built-in 2014-01-28 13:20:31 -08:00
inode-item.c btrfs: kill the key type accessor helpers 2014-09-17 13:37:12 -07:00
inode-map.c btrfs: cleanup ino cache members of btrfs_root 2014-09-17 13:37:09 -07:00
inode-map.h
inode.c Btrfs: report error after failure inlining extent in compressed write path 2014-11-20 17:14:28 -08:00
ioctl.c vfs: export check_sticky() 2014-10-24 00:14:36 +02:00
Kconfig Btrfs: fix btrfs boot when compiled as built-in 2014-01-28 13:20:31 -08:00
locking.c Btrfs: fix deadlocks with trylock on tree nodes 2014-06-19 14:19:55 -07:00
locking.h Btrfs: remove btrfs_try_spin_lock 2013-03-14 14:57:10 -04:00
lzo.c btrfs: use DIV_ROUND_UP instead of open-coded variants 2014-09-17 13:37:17 -07:00
Makefile Btrfs: add sanity tests for new qgroup accounting code 2014-06-09 17:20:49 -07:00
math.h Btrfs: cleanup duplicated division functions 2012-12-11 13:31:30 -05:00
ordered-data.c Btrfs: add helper btrfs_fdatawrite_range 2014-11-20 17:14:28 -08:00
ordered-data.h btrfs: disable strict file flushes for renames and truncates 2014-08-15 07:43:42 -07:00
orphan.c btrfs: kill the key type accessor helpers 2014-09-17 13:37:12 -07:00
print-tree.c btrfs: remove parameter blocksize from read_tree_block 2014-10-02 17:14:50 +02:00
print-tree.h btrfs: make static code static & remove dead code 2013-05-06 15:55:23 -04:00
props.c Btrfs: add support for inode properties 2014-01-28 13:20:24 -08:00
props.h Btrfs: add support for inode properties 2014-01-28 13:20:24 -08:00
qgroup.c btrfs: move checks for DUMMY_ROOT into a helper 2014-10-02 17:30:33 +02:00
qgroup.h btrfs: qgroup: account shared subtrees during snapshot delete 2014-08-15 07:43:14 -07:00
raid56.c btrfs: use DIV_ROUND_UP instead of open-coded variants 2014-09-17 13:37:17 -07:00
raid56.h Btrfs: RAID5 and RAID6 2013-02-01 14:24:23 -05:00
rcu-string.h
reada.c btrfs: use nodesize everywhere, kill leafsize 2014-09-17 13:37:14 -07:00
relocation.c Merge branch 'cleanup/blocksize-diet-part1' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux into for-linus 2014-10-04 09:57:14 -07:00
root-tree.c Btrfs: use bitfield instead of integer data type for the some variants in btrfs_root 2014-06-09 17:20:40 -07:00
scrub.c btrfs: fix dead lock while running replace and defrag concurrently 2014-11-20 17:20:08 -08:00
send.c Merge branch 'cleanup/misc-for-3.18' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux into for-linus 2014-10-04 09:56:45 -07:00
send.h btrfs: make static code static & remove dead code 2013-05-06 15:55:23 -04:00
struct-funcs.c
super.c Btrfs: don't take the chunk_mutex/dev_list mutex in statfs V2 2014-11-20 17:20:05 -08:00
sysfs.c btrfs: sysfs label interface should check for read only FS 2014-09-17 13:38:01 -07:00
sysfs.h btrfs: code optimize: BTRFS_ATTR_RW could set the mode 2014-09-17 13:37:59 -07:00
transaction.c Btrfs: make find_first_extent_bit be able to cache any state 2014-11-20 17:14:29 -08:00
transaction.h Btrfs: deal with convert_extent_bit errors to avoid fs corruption 2014-11-20 17:14:29 -08:00
tree-defrag.c Btrfs: use bitfield instead of integer data type for the some variants in btrfs_root 2014-06-09 17:20:40 -07:00
tree-log.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs 2014-11-01 10:41:26 -07:00
tree-log.h Btrfs: fix data corruption after fast fsync and writeback error 2014-09-19 06:57:51 -07:00
ulist.c Btrfs: do not export ulist functions 2014-01-29 07:06:27 -08:00
ulist.h Btrfs: Fix memory corruption by ulist_add_merge() on 32bit arch 2014-08-15 07:43:19 -07:00
uuid-tree.c Btrfs: make btrfs_search_forward return with nodes unlocked 2014-09-17 13:38:02 -07:00
volumes.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs 2014-10-11 08:03:52 -04:00
volumes.h Btrfs: remove empty block groups automatically 2014-09-22 17:13:21 -07:00
xattr.c Btrfs: make xattr replace operations atomic 2014-11-20 17:20:07 -08:00
xattr.h btrfs: use generic posix ACL infrastructure 2014-01-25 23:58:18 -05:00
zlib.c btrfs compression: merge inflate and deflate z_streams 2014-09-17 13:37:33 -07:00