linux/fs/ocfs2
Xiaowei.Hu 309a85b686 ocfs2: ac->ac_allow_chain_relink=0 won't disable group relink
ocfs2_block_group_alloc_discontig() disables chain relink by setting
ac->ac_allow_chain_relink = 0 because it grabs clusters from multiple
cluster groups.

It doesn't keep the credits for all chain relink,but
ocfs2_claim_suballoc_bits overrides this in this call trace:
ocfs2_block_group_claim_bits()->ocfs2_claim_clusters()->
__ocfs2_claim_clusters()->ocfs2_claim_suballoc_bits()
ocfs2_claim_suballoc_bits set ac->ac_allow_chain_relink = 1; then call
ocfs2_search_chain() one time and disable it again, and then we run out
of credits.

Fix is to allow relink by default and disable it in
ocfs2_block_group_alloc_discontig.

Without this patch, End-users will run into a crash due to run out of
credits, backtrace like this:

  RIP: 0010:[<ffffffffa0808b14>]  [<ffffffffa0808b14>]
  jbd2_journal_dirty_metadata+0x164/0x170 [jbd2]
  RSP: 0018:ffff8801b919b5b8  EFLAGS: 00010246
  RAX: 0000000000000000 RBX: ffff88022139ddc0 RCX: ffff880159f652d0
  RDX: ffff880178aa3000 RSI: ffff880159f652d0 RDI: ffff880087f09bf8
  RBP: ffff8801b919b5e8 R08: 0000000000000000 R09: 0000000000000000
  R10: 0000000000001e00 R11: 00000000000150b0 R12: ffff880159f652d0
  R13: ffff8801a0cae908 R14: ffff880087f09bf8 R15: ffff88018d177800
  FS:  00007fc9b0b6b6e0(0000) GS:ffff88022fd40000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
  CR2: 000000000040819c CR3: 0000000184017000 CR4: 00000000000006e0
  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
  Process dd (pid: 9945, threadinfo ffff8801b919a000, task ffff880149a264c0)
  Call Trace:
    ocfs2_journal_dirty+0x2f/0x70 [ocfs2]
    ocfs2_relink_block_group+0x111/0x480 [ocfs2]
    ocfs2_search_chain+0x455/0x9a0 [ocfs2]
    ...

Signed-off-by: Xiaowei.Hu <xiaowei.hu@oracle.com>
Reviewed-by: Srinivas Eeda <srinivas.eeda@oracle.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-02-27 19:10:09 -08:00
..
cluster
dlm Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2013-02-26 20:16:07 -08:00
dlmfs
acl.c
acl.h
alloc.c
alloc.h
aops.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2013-02-26 20:16:07 -08:00
aops.h
blockcheck.c
blockcheck.h
buffer_head_io.c
buffer_head_io.h
dcache.c
dcache.h
dir.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2013-02-26 20:16:07 -08:00
dir.h
dlmglue.c
dlmglue.h
export.c fs: encode_fh: return FILEID_INVALID if invalid fid_type 2013-02-26 02:46:10 -05:00
export.h
extent_map.c
extent_map.h
file.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2013-02-26 20:16:07 -08:00
file.h
heartbeat.c
heartbeat.h
inode.c
inode.h
ioctl.c
ioctl.h
journal.c
journal.h
Kconfig
localalloc.c
localalloc.h
locks.c
locks.h
Makefile
mmap.c
mmap.h
move_extents.c
move_extents.h
namei.c
namei.h
ocfs1_fs_compat.h
ocfs2.h
ocfs2_fs.h
ocfs2_ioctl.h
ocfs2_lockid.h
ocfs2_lockingver.h
ocfs2_trace.h
quota.h
quota_global.c
quota_local.c
refcounttree.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2013-02-26 20:16:07 -08:00
refcounttree.h
reservations.c
reservations.h
resize.c
resize.h
slot_map.c
slot_map.h
stack_o2cb.c
stack_user.c
stackglue.c
stackglue.h
suballoc.c ocfs2: ac->ac_allow_chain_relink=0 won't disable group relink 2013-02-27 19:10:09 -08:00
suballoc.h ocfs2: ac->ac_allow_chain_relink=0 won't disable group relink 2013-02-27 19:10:09 -08:00
super.c
super.h
symlink.c ocfs2: Fix oops in ocfs2_fast_symlink_readpage() code path 2013-02-26 02:46:12 -05:00
symlink.h
sysfile.c
sysfile.h
uptodate.c
uptodate.h
ver.c
ver.h
xattr.c ocfs2: fix ocfs2_init_security_and_acl() to initialize acl correctly 2013-02-27 19:10:09 -08:00
xattr.h