linux-stable.git/fs/jbd2/checkpoint.c, branch linux-3.4.y

jbd2: avoid infinite loop when destroying aborted journal

2015-10-22T01:20:08+00:00

commit 841df7df196237ea63233f0f9eaa41db53afd70f upstream.

Commit 6f6a6fda2945 "jbd2: fix ocfs2 corrupt when updating journal
superblock fails" changed jbd2_cleanup_journal_tail() to return EIO
when the journal is aborted. That makes logic in
jbd2_log_do_checkpoint() bail out which is fine, except that
jbd2_journal_destroy() expects jbd2_log_do_checkpoint() to always make
a progress in cleaning the journal. Without it jbd2_journal_destroy()
just loops in an infinite loop.

Fix jbd2_journal_destroy() to cleanup journal checkpoint lists of
jbd2_log_do_checkpoint() fails with error.

Reported-by: Eryu Guan 
Tested-by: Eryu Guan 
Fixes: 6f6a6fda294506dfe0e3e0a253bb2d2923f28f0a
Signed-off-by: Jan Kara 
Signed-off-by: Theodore Ts'o 
[lizf: Backported to 3.4: adjust context]
Signed-off-by: Zefan Li

jbd2: fix ocfs2 corrupt when updating journal superblock fails

2015-10-22T01:20:04+00:00

commit 6f6a6fda294506dfe0e3e0a253bb2d2923f28f0a upstream.

If updating journal superblock fails after journal data has been
flushed, the error is omitted and this will mislead the caller as a
normal case.  In ocfs2, the checkpoint will be treated successfully
and the other node can get the lock to update. Since the sb_start is
still pointing to the old log block, it will rewrite the journal data
during journal recovery by the other node. Thus the new updates will
be overwritten and ocfs2 corrupts.  So in above case we have to return
the error, and ocfs2_commit_cache will take care of the error and
prevent the other node to do update first.  And only after recovering
journal it can do the new updates.

The issue discussion mail can be found at:
https://oss.oracle.com/pipermail/ocfs2-devel/2015-June/010856.html
http://comments.gmane.org/gmane.comp.file-systems.ext4/48841

[ Fixed bug in patch which allowed a non-negative error return from
  jbd2_cleanup_journal_tail() to leak out of jbd2_fjournal_flush(); this
  was causing xfstests ext4/306 to fail. -- Ted ]

Reported-by: Yiwen Jiang 
Signed-off-by: Joseph Qi 
Signed-off-by: Theodore Ts'o 
Tested-by: Yiwen Jiang 
Cc: Junxiao Bi 
Signed-off-by: Zefan Li

jbd2: use GFP_NOFS in jbd2_cleanup_journal_tail()

2015-10-22T01:20:04+00:00

commit b4f1afcd068f6e533230dfed00782cd8a907f96b upstream.

jbd2_cleanup_journal_tail() can be invoked by jbd2__journal_start()
So allocations should be done with GFP_NOFS

[Full stack trace snipped from 3.10-rh7]
[] dump_stack+0x19/0x1b
[] warn_slowpath_common+0x61/0x80
[] warn_slowpath_null+0x1a/0x20
[] slab_pre_alloc_hook.isra.31.part.32+0x15/0x17
[] kmem_cache_alloc+0x55/0x210
[] ? mempool_alloc_slab+0x15/0x20
[] mempool_alloc_slab+0x15/0x20
[] mempool_alloc+0x69/0x170
[] ? _raw_spin_unlock_irq+0xe/0x20
[] ? finish_task_switch+0x5d/0x150
[] bio_alloc_bioset+0x1be/0x2e0
[] blkdev_issue_flush+0x99/0x120
[] jbd2_cleanup_journal_tail+0x93/0xa0 [jbd2] -->GFP_KERNEL
[] jbd2_log_do_checkpoint+0x221/0x4a0 [jbd2]
[] __jbd2_log_wait_for_space+0xa7/0x1e0 [jbd2]
[] start_this_handle+0x2d8/0x550 [jbd2]
[] ? __memcg_kmem_put_cache+0x29/0x30
[] ? kmem_cache_alloc+0x130/0x210
[] jbd2__journal_start+0xba/0x190 [jbd2]
[] ? lru_cache_add+0xe/0x10
[] ? ext4_da_write_begin+0xf9/0x330 [ext4]
[] __ext4_journal_start_sb+0x77/0x160 [ext4]
[] ext4_da_write_begin+0xf9/0x330 [ext4]
[] generic_file_buffered_write_iter+0x10c/0x270
[] __generic_file_write_iter+0x178/0x390
[] __generic_file_aio_write+0x8b/0xb0
[] generic_file_aio_write+0x5d/0xc0
[] ext4_file_write+0xa9/0x450 [ext4]
[] ? pipe_read+0x379/0x4f0
[] do_sync_write+0x90/0xe0
[] vfs_write+0xbd/0x1e0
[] SyS_write+0x58/0xb0
[] system_call_fastpath+0x16/0x1b

Signed-off-by: Dmitry Monakhov 
Signed-off-by: Theodore Ts'o 
Signed-off-by: Zefan Li

jbd2: remove bh_state lock from checkpointing code

2012-03-14T02:45:25+00:00

All accesses to checkpointing entries in journal_head are protected
by j_list_lock. Thus __jbd2_journal_remove_checkpoint() doesn't really
need bh_state lock.

Also the only part of journal head that the rest of checkpointing code
needs to check is jh->b_transaction which is safe to read under
j_list_lock.

So we can safely remove bh_state lock from all of checkpointing code which
makes it considerably prettier.

Signed-off-by: Jan Kara 
Signed-off-by: "Theodore Ts'o"

jbd2: fix BH_JWrite setting in checkpointing code

2012-03-14T02:24:54+00:00

BH_JWrite bit should be set when buffer is written to the journal. So
checkpointing shouldn't set this bit when writing out buffer. This didn't
cause any observable bug since BH_JWrite bit is used only for debugging
purposes but it's good to have this consistent.

Signed-off-by: Jan Kara 
Signed-off-by: "Theodore Ts'o"

jbd2: issue cache flush after checkpointing even with internal journal

2012-03-14T02:22:54+00:00

When we reach jbd2_cleanup_journal_tail(), there is no guarantee that
checkpointed buffers are on a stable storage - especially if buffers were
written out by jbd2_log_do_checkpoint(), they are likely to be only in disk's
caches. Thus when we update journal superblock effectively removing old
transaction from journal, this write of superblock can get to stable storage
before those checkpointed buffers which can result in filesystem corruption
after a crash. Thus we must unconditionally issue a cache flush before we
update journal superblock in these cases.

A similar problem can also occur if journal superblock is written only in
disk's caches, other transaction starts reusing space of the transaction
cleaned from the log and power failure happens. Subsequent journal replay would
still try to replay the old transaction but some of it's blocks may be already
overwritten by the new transaction. For this reason we must use WRITE_FUA when
updating log tail and we must first write new log tail to disk and update
in-memory information only after that.

Signed-off-by: Jan Kara 
Signed-off-by: "Theodore Ts'o"

jbd2: split updating of journal superblock and marking journal empty

2012-03-13T19:41:04+00:00

There are three case of updating journal superblock. In the first case, we want
to mark journal as empty (setting s_sequence to 0), in the second case we want
to update log tail, in the third case we want to update s_errno. Split these
cases into separate functions. It makes the code slightly more straightforward
and later patches will make the distinction even more important.

Signed-off-by: Jan Kara 
Signed-off-by: "Theodore Ts'o"

jbd2: allocate transaction from separate slab cache

2012-02-20T22:53:02+00:00

There is normally only a handful of these active at any one time, but
putting them in a separate slab cache makes debugging memory
corruption problems easier.  Manish Katiyar also wanted this make it
easier to test memory failure scenarios in the jbd2 layer.

Cc: Manish Katiyar 
Signed-off-by: Yongqiang Yang 
Signed-off-by: "Theodore Ts'o"

jbd2: add drop_transaction/update_superblock_end tracepoints

2012-02-20T22:53:01+00:00

This patch adds trace_jbd2_drop_transaction and
trace_jbd2_update_superblock_end because there are similar tracepoints
in jbd and they are needed in jbd2 as well.

Reviewed-by: Lukas Czerner 
Signed-off-by: Seiji Aguchi 
Signed-off-by: "Theodore Ts'o"

treewide: Fix comment and string typo 'bufer'

2011-12-06T08:53:40+00:00

Signed-off-by: Paul Bolle 
Signed-off-by: Jiri Kosina