JBD2 layer support triggers which are called when journaling layer moves
buffer to a certain state. We can use the frozen trigger, which gets
called when buffer data is frozen and about to be written out to the
journal, to compute block checksums for some buffer types (similarly as
does ocfs2). This avoids unnecessary repeated recomputation of the
checksum (at the cost of larger window where memory corruption won't be
caught by checksumming) and is even necessary when there are
unsynchronized updaters of the checksummed data.
So add superblock and journal trigger type arguments to
ext4_journal_get_write_access() and ext4_journal_get_create_access() so
that frozen triggers can be set accordingly. Also add inode argument to
ext4_walk_page_buffers() and all the callbacks used with that function
for the same purpose. This patch is mostly only a change of prototype of
the above mentioned functions and a few small helpers. Real checksumming
will come later.
Reviewed-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20210816095713.16537-1-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Fix a signed vs unsigned and a void * pointer arithmetic warning.
This cleanup is also in e2fsprogs commit aec460db9a93 ("e2fsck: clean
up two gcc -Wall warnings in recovery.c").
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Remove unused variable store which was never used.
This fix is also in e2fsprogs commit 99a2294f85f0 ("e2fsck: value
stored to err is never read").
Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
This commit applies the e2fsck/recovery.c portions of commit
1e0c8ca7c08a ("e2fsck: fix portability problems caused by unaligned
accesses) from the e2fsprogs git tree.
The on-disk format for the ext4 journal can have unaigned 32-bit
integers. This can happen when replaying a journal using a obsolete
checksum format (which was never popularly used, since the v3 format
replaced v2 while the metadata checksum feature was being stablized).
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
The function jbd2_journal_unregister_shrinker() was getting called
twice when the file system was getting unmounted. On Power and ARM
platforms this was causing kernel crash when unmounting the file
system, when a percpu_counter was destroyed twice.
Fix this by removing jbd2_journal_[un]register_shrinker() functions,
and inlining the shrinker setup and teardown into
journal_init_common() and jbd2_journal_destroy(). This means that
ext4 and ocfs2 now no longer need to know about registering and
unregistering jbd2's shrinker.
Also, while we're at it, rename the percpu counter from
j_jh_shrink_count to j_checkpoint_jh_count, since this makes it
clearer what this counter is intended to track.
Link: https://lore.kernel.org/r/20210705145025.3363130-1-tytso@mit.edu
Fixes: 4ba3fcdde7 ("jbd2,ext4: add a shrinker to release checkpointed buffers")
Reported-by: Jon Hunter <jonathanh@nvidia.com>
Reported-by: Sachin Sant <sachinp@linux.vnet.ibm.com>
Tested-by: Sachin Sant <sachinp@linux.vnet.ibm.com>
Tested-by: Jon Hunter <jonathanh@nvidia.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Export jbd2_journal_[un]register_shrinker() to fix this error when
ext4 is built as a module:
ERROR: modpost: "jbd2_journal_unregister_shrinker" undefined!
ERROR: modpost: "jbd2_journal_register_shrinker" undefined!
Fixes: 4ba3fcdde7 ("jbd2,ext4: add a shrinker to release checkpointed buffers")
Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20210630083638.140218-1-yi.zhang@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Now that __try_to_free_cp_buf() remove checkpointed buffer or transaction
when the buffer is not 'busy', which is only called by
journal_clean_one_cp_list(). This patch simplify this function by remove
__try_to_free_cp_buf() and invoke __cp_buffer_busy() directly.
Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20210610112440.3438139-7-yi.zhang@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Current metadata buffer release logic in bdev_try_to_free_page() have
a lot of use-after-free issues when umount filesystem concurrently, and
it is difficult to fix directly because ext4 is the only user of
s_op->bdev_try_to_free_page callback and we may have to add more special
refcount or lock that is only used by ext4 into the common vfs layer,
which is unacceptable.
One better solution is remove the bdev_try_to_free_page callback, but
the real problem is we cannot easily release journal_head on the
checkpointed buffer, so try_to_free_buffers() cannot release buffers and
page under memory pressure, which is more likely to trigger
out-of-memory. So we cannot remove the callback directly before we find
another way to release journal_head.
This patch introduce a shrinker to free journal_head on the checkpointed
transaction. After the journal_head got freed, try_to_free_buffers()
could free buffer properly.
Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Suggested-by: Jan Kara <jack@suse.cz>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20210610112440.3438139-6-yi.zhang@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Now that __jbd2_journal_remove_checkpoint() can detect buffer io error
and mark journal checkpoint error, then we abort the journal later
before updating log tail to ensure the filesystem works consistently.
So we could remove other redundant buffer io error checkes.
Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20210610112440.3438139-5-yi.zhang@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Now that we can be sure the journal is aborted once a buffer has failed
to be written back to disk, we can remove the journal abort logic in
jbd2_journal_try_to_free_buffers() which was introduced in
commit c044f3d836 ("jbd2: abort journal if free a async write error
metadata buffer"), because it may cost and propably is not safe.
Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20210610112440.3438139-4-yi.zhang@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Although we merged c044f3d836 ("jbd2: abort journal if free a async
write error metadata buffer"), there is a race between
jbd2_journal_try_to_free_buffers() and jbd2_journal_destroy(), so the
jbd2_log_do_checkpoint() may still fail to detect the buffer write
io error flag which may lead to filesystem inconsistency.
jbd2_journal_try_to_free_buffers() ext4_put_super()
jbd2_journal_destroy()
__jbd2_journal_remove_checkpoint()
detect buffer write error jbd2_log_do_checkpoint()
jbd2_cleanup_journal_tail()
<--- lead to inconsistency
jbd2_journal_abort()
Fix this issue by introducing a new atomic flag which only have one
JBD2_CHECKPOINT_IO_ERROR bit now, and set it in
__jbd2_journal_remove_checkpoint() when freeing a checkpoint buffer
which has write_io_error flag. Then jbd2_journal_destroy() will detect
this mark and abort the journal to prevent updating log tail.
Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20210610112440.3438139-3-yi.zhang@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Using no_printk() for jbd_debug() revealed two warnings:
fs/jbd2/recovery.c: In function 'fc_do_one_pass':
fs/jbd2/recovery.c:256:30: error: format '%d' expects a matching 'int' argument [-Werror=format=]
256 | jbd_debug(3, "Processing fast commit blk with seq %d");
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
fs/ext4/fast_commit.c: In function 'ext4_fc_replay_add_range':
fs/ext4/fast_commit.c:1732:30: error: format '%d' expects argument of type 'int', but argument 2 has type 'long unsigned int' [-Werror=format=]
1732 | jbd_debug(1, "Converting from %d to %d %lld",
The first one was added incorrectly, and was also missing a few newlines
in debug output, and the second one happened when the type of an
argument changed.
Reported-by: kernel test robot <lkp@intel.com>
Fixes: d556435156 ("jbd2: avoid -Wempty-body warnings")
Fixes: 6db0746189 ("ext4: use BIT() macro for BH_** state bits")
Fixes: 5b849b5f96 ("jbd2: fast commit recovery path")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20210409201211.1866633-1-arnd@kernel.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Add a helper to read number of fast commit blocks from jbd2 superblock
and also rename the JBD2_MIN_FC_BLKS to
JBD2_DEFAULT_FAST_COMMIT_BLOCKS since this constant is just the
default number of fast commit blocks to use in case number of fast
commit blocks isn't set in jbd2 superblock.
Signed-off-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com>
Link: https://lore.kernel.org/r/20201120202232.2240293-2-harshadshirwadkar@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Add missing __acquires() and __releases() annotations. Also, in an
"this should never happen" WARN_ON check, if it *does* actually
happen, we need to release j_state_lock since this function is always
supposed to release that lock. Otherwise, things will quickly grind
to a halt after the WARN_ON trips.
Fixes: 96f1e09745 ("jbd2: avoid long hold times of j_state_lock...")
Cc: stable@kernel.org
Signed-off-by: Theodore Ts'o <tytso@mit.edu>