linux_dsm_epyc7002/fs/ocfs2
Changwei Ge 71a3694404 ocfs2: try to reuse extent block in dealloc without meta_alloc
A crash issue was reported by John Lightsey with a call trace as follows:

  ocfs2_split_extent+0x1ad3/0x1b40 [ocfs2]
  ocfs2_change_extent_flag+0x33a/0x470 [ocfs2]
  ocfs2_mark_extent_written+0x172/0x220 [ocfs2]
  ocfs2_dio_end_io+0x62d/0x910 [ocfs2]
  dio_complete+0x19a/0x1a0
  do_blockdev_direct_IO+0x19dd/0x1eb0
  __blockdev_direct_IO+0x43/0x50
  ocfs2_direct_IO+0x8f/0xa0 [ocfs2]
  generic_file_direct_write+0xb2/0x170
  __generic_file_write_iter+0xc3/0x1b0
  ocfs2_file_write_iter+0x4bb/0xca0 [ocfs2]
  __vfs_write+0xae/0xf0
  vfs_write+0xb8/0x1b0
  SyS_write+0x4f/0xb0
  system_call_fastpath+0x16/0x75

The BUG code told that extent tree wants to grow but no metadata was
reserved ahead of time.  From my investigation into this issue, the root
cause it that although enough metadata is not reserved, there should be
enough for following use.  Rightmost extent is merged into its left one
due to a certain times of marking extent written.  Because during
marking extent written, we got many physically continuous extents.  At
last, an empty extent showed up and the rightmost path is removed from
extent tree.

Add a new mechanism to reuse extent block cached in dealloc which were
just unlinked from extent tree to solve this crash issue.

Criteria is that during marking extents *written*, if extent rotation
and merging results in unlinking extent with growing extent tree later
without any metadata reserved ahead of time, try to reuse those extents
in dealloc in which deleted extents are cached.

Also, this patch addresses the issue John reported that ::dw_zero_count
is not calculated properly.

After applying this patch, the issue John reported was gone.  Thanks for
the reproducer provided by John.  And this patch has passed
ocfs2-test(29 cases) suite running by New H3C Group.

[ge.changwei@h3c.com: fix static checker warnning]
  Link: http://lkml.kernel.org/r/63ADC13FD55D6546B7DECE290D39E373F29196AE@H3CMLB12-EX.srv.huawei-3com.com
[akpm@linux-foundation.org: brelse(NULL) is legal]
Link: http://lkml.kernel.org/r/1515479070-32653-2-git-send-email-ge.changwei@h3c.com
Signed-off-by: Changwei Ge <ge.changwei@h3c.com>
Reported-by: John Lightsey <john@nixnuts.net>
Tested-by: John Lightsey <john@nixnuts.net>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Joseph Qi <jiangqi903@gmail.com>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Mark Fasheh <mfasheh@versity.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-01-31 17:18:35 -08:00
..
cluster ocfs2/cluster: close a race that fence can't be triggered 2018-01-31 17:18:35 -08:00
dlm fs/ocfs2/dlm/dlmmaster.c: clean up dead code 2018-01-31 17:18:34 -08:00
dlmfs fs: annotate ->poll() instances 2017-11-27 16:20:05 -05:00
acl.c ocfs2/acl: use 'ip_xattr_sem' to protect getting extended attribute 2018-01-31 17:18:35 -08:00
acl.h ocfs2: make ocfs2_set_acl() static 2017-09-06 17:27:24 -07:00
alloc.c ocfs2: try to reuse extent block in dealloc without meta_alloc 2018-01-31 17:18:35 -08:00
alloc.h ocfs2: try to reuse extent block in dealloc without meta_alloc 2018-01-31 17:18:35 -08:00
aops.c ocfs2: try to reuse extent block in dealloc without meta_alloc 2018-01-31 17:18:35 -08:00
aops.h ocfs2: clean up unused 'page' parameter in ocfs2_write_end_nolock() 2016-12-12 18:55:06 -08:00
blockcheck.c ocfs2: kill endianness abuses in blockcheck.c 2012-05-29 23:28:35 -04:00
blockcheck.h
buffer_head_io.c block,fs: untangle fs.h and blk_types.h 2016-11-01 09:43:26 -06:00
buffer_head_io.h ocfs2: clean up some unused function declarations 2017-11-15 18:21:01 -08:00
dcache.c VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
dcache.h ocfs2: revert iput deferring code in ocfs2_drop_dentry_lock 2014-04-03 16:20:55 -07:00
dir.c ocfs2: convert to new i_version API 2018-01-29 06:42:21 -05:00
dir.h VFS: normal filesystems (and lustre): d_inode() annotations 2015-04-15 15:06:57 -04:00
dlmglue.c ocfs2: try a blocking lock before return AOP_TRUNCATED_PAGE 2018-01-31 17:18:35 -08:00
dlmglue.h ocfs2/dlmglue: prepare tracking logic to avoid recursive cluster lock 2017-02-22 16:41:27 -08:00
export.c ocfs2: Use ERR_CAST() to avoid cross-structure cast 2017-05-28 10:11:49 -07:00
export.h
extent_map.c ocfs2: neaten do_error, ocfs2_error and ocfs2_abort 2015-09-04 16:54:41 -07:00
extent_map.h
file.c Rename superblock flags (MS_xyz -> SB_xyz) 2017-11-27 13:05:09 -08:00
file.h statx: Add a system call to make enhanced file info available 2017-03-02 20:51:15 -05:00
filecheck.c Pass mode to wait_on_atomic_t() action funcs and provide default actions 2017-11-13 15:38:16 +00:00
filecheck.h ocfs2: sysfile interfaces for online file check 2016-03-22 15:36:02 -07:00
heartbeat.c
heartbeat.h
inode.c ocfs2: convert to new i_version API 2018-01-29 06:42:21 -05:00
inode.h ocfs2: convert inode refcount test to a helper 2016-12-10 12:39:45 -08:00
ioctl.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
ioctl.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
journal.c ocfs2: clean up some dead code 2017-09-06 17:27:24 -07:00
journal.h jbd2: add support for avoiding data writes during transaction commits 2016-04-24 00:56:07 -04:00
Kconfig
localalloc.c ocfs2: fix occurring deadlock by changing ocfs2_wq from global to local 2016-03-25 16:37:42 -07:00
localalloc.h ocfs2: free allocated clusters if error occurs after ocfs2_claim_clusters 2014-02-06 13:48:51 -08:00
locks.c ocfs2: fix flock panic issue 2015-12-29 17:45:49 -08:00
locks.h
Makefile License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
mmap.c mm, fs: reduce fault, page_mkwrite, and pfn_mkwrite to take only vmf 2017-02-24 17:46:54 -08:00
mmap.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
move_extents.c ocfs2: clean up some dead code 2017-09-06 17:27:24 -07:00
move_extents.h
namei.c ocfs2: convert to new i_version API 2018-01-29 06:42:21 -05:00
namei.h ocfs2: do not include dio entry in case of orphan scan 2015-11-05 19:34:48 -08:00
ocfs1_fs_compat.h
ocfs2_fs.h ocfs2: use magic.h 2017-07-06 16:24:30 -07:00
ocfs2_ioctl.h
ocfs2_lockid.h
ocfs2_lockingver.h
ocfs2_trace.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
ocfs2.h ocfs2: clean up some dead code 2017-09-06 17:27:24 -07:00
quota_global.c ocfs2: convert to new i_version API 2018-01-29 06:42:21 -05:00
quota_local.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
quota.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
refcounttree.c ocfs2: clean up some dead code 2017-09-06 17:27:24 -07:00
refcounttree.h ocfs2: implement the VFS clone_range, copy_range, and dedupe_range features 2016-12-10 12:39:45 -08:00
reservations.c ocfs2: make resv_lock spinlock static 2015-02-10 14:30:29 -08:00
reservations.h
resize.c ocfs2: solve a problem of crossing the boundary in updating backups 2016-03-25 16:37:42 -07:00
resize.h
slot_map.c ocfs2: clean up an unneeded goto in ocfs2_put_slot() 2016-05-19 19:12:14 -07:00
slot_map.h
stack_o2cb.c ocfs2: avoid a pointless delay in o2cb_cluster_check() 2015-04-14 16:48:57 -07:00
stack_user.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
stackglue.c ocfs2: constify attribute_group structures 2017-07-06 16:24:30 -07:00
stackglue.h ocfs2: fix crash caused by stale lvb with fsdlm plugin 2017-01-10 18:31:54 -08:00
suballoc.c ocfs2: clean dead code in suballoc.c 2018-01-31 17:18:35 -08:00
suballoc.h ocfs2: rollback alloc_dinode counts when ocfs2_block_group_set_bits() failed 2014-04-03 16:20:56 -07:00
super.c ocfs2: return -EROFS to mount.ocfs2 if inode block is invalid 2018-01-31 17:18:35 -08:00
super.h ocfs2: remove unused declaration ocfs2_publish_get_mount_state() 2017-11-15 18:21:01 -08:00
symlink.c vfs: remove ".readlink = generic_readlink" assignments 2016-12-09 16:45:04 +01:00
symlink.h ocfs: simplify symlink handling 2012-05-29 23:28:40 -04:00
sysfile.c ocfs2: avoid system inode ref confusion by adding mutex lock 2014-04-03 16:20:57 -07:00
sysfile.h
uptodate.c ocfs2: remove NULL assignments on static 2014-06-04 16:53:53 -07:00
uptodate.h
xattr.c ocfs2/acl: use 'ip_xattr_sem' to protect getting extended attribute 2018-01-31 17:18:35 -08:00
xattr.h ocfs2: fix posix_acl_create deadlock 2016-05-12 15:52:50 -07:00