kernel.git/fs/jbd2/journal.c, branch linux-3.17.y

jbd2: fix descriptor block size handling errors with journal_csum

2014-08-29T02:22:29Z

It turns out that there are some serious problems with the on-disk format of journal checksum v2. The foremost is that the function to calculate descriptor tag size returns sizes that are too big. This causes alignment issues on some architectures and is compounded by the fact that some parts of jbd2 use the structure size (incorrectly) to determine the presence of a 64bit journal instead of checking the feature flags. Therefore, introduce journal checksum v3, which enlarges the descriptor block tag format to allow for full 32-bit checksums of journal blocks, fix the journal tag function to return the correct sizes, and fix the jbd2 recovery code to use feature flags to determine 64bitness. Add a few function helpers so we don't have to open-code quite so many pieces. Switching to a 16-byte block size was found to increase journal size overhead by a maximum of 0.1%, to convert a 32-bit journal with no checksumming to a 32-bit journal with checksum v3 enabled. Signed-off-by: Darrick J. Wong Reported-by: TR Reardon Signed-off-by: Theodore Ts'o Cc: stable@vger.kernel.org

jbd2: don't hold j_state_lock while calling wake_up()

2014-03-09T00:11:36Z

The j_state_lock is one of the hottest locks in the jbd2 layer and thus one of its scalability bottlenecks. We don't need to be holding the j_state_lock while we are calling wake_up(&journal->j_wait_commit), so release the lock a little bit earlier. Signed-off-by: "Theodore Ts'o"

jbd2: mark file-local functions as static

2014-02-18T01:49:04Z

Mark functions as static in jbd2/journal.c because they are not used outside this file. This eliminates the following warning in jbd2/journal.c: fs/jbd2/journal.c:125:5: warning: no previous prototype for ‘jbd2_verify_csum_type’ [-Wmissing-prototypes] fs/jbd2/journal.c:146:5: warning: no previous prototype for ‘jbd2_superblock_csum_verify’ [-Wmissing-prototypes] fs/jbd2/journal.c:154:6: warning: no previous prototype for ‘jbd2_superblock_csum_set’ [-Wmissing-prototypes] Signed-off-by: Rashika Kheria Signed-off-by: "Theodore Ts'o" Reviewed-by: Josh Triplett Reviewed-by: Darrick J. Wong

jbd2: rename obsoleted msg JBD->JBD2

2013-12-09T02:14:59Z

Rename performed via: perl -pi -e 's/JBD:/JBD2:/g' fs/jbd2/*.c Signed-off-by: Dmitry Monakhov Signed-off-by: "Theodore Ts'o" Reviewed-by: Carlos Maiolino

jbd2: revise KERN_EMERG error messages

2013-12-09T02:13:59Z

Some of KERN_EMERG printk messages do not really deserve this log level and the one in log_wait_commit() is even rather useless (the journal has been previously aborted and *that* is where we should have been complaining). So make some messages just KERN_ERR and remove the useless message. Signed-off-by: Jan Kara Signed-off-by: "Theodore Ts'o"

jbd2: Fix endian mixing problems in the checksumming code

2013-08-28T18:59:58Z

In the jbd2 checksumming code, explicitly declare separate variables with endianness information so that we don't get confused and screw things up again. Also fixes sparse warnings. Signed-off-by: Darrick J. Wong Signed-off-by: "Theodore Ts'o"

jbd2: move superblock checksum calculation to jbd2_write_superblock()

2013-07-01T12:12:38Z

Some of the functions which modify the jbd2 superblock were not updating the checksum before calling jbd2_write_superblock(). Move the call to jbd2_superblock_csum_set() to jbd2_write_superblock(), so that the checksum is calculated consistently. Signed-off-by: "Theodore Ts'o" Cc: Darrick J. Wong Cc: stable@vger.kernel.org

jbd2: use a single printk for jbd_debug()

2013-06-13T03:04:04Z

Since the jbd_debug() is implemented with two separate printk() calls, it can lead to corrupted and misleading debug output like the following (see lines marked with "*"): [ 290.339362] (fs/jbd2/journal.c, 203): kjournald2: kjournald2 wakes [ 290.339365] (fs/jbd2/journal.c, 155): kjournald2: commit_sequence=42103, commit_request=42104 [ 290.339369] (fs/jbd2/journal.c, 158): kjournald2: OK, requests differ [* 290.339376] (fs/jbd2/journal.c, 648): jbd2_log_wait_commit: [* 290.339379] (fs/jbd2/commit.c, 370): jbd2_journal_commit_transaction: JBD2: want 42104, j_commit_sequence=42103 [* 290.339382] JBD2: starting commit of transaction 42104 [ 290.339410] (fs/jbd2/revoke.c, 566): jbd2_journal_write_revoke_records: Wrote 0 revoke records [ 290.376555] (fs/jbd2/commit.c, 1088): jbd2_journal_commit_transaction: JBD2: commit 42104 complete, head 42079 i.e. the debug output from log_wait_commit and journal_commit_transaction have become interleaved. The output should have been: (fs/jbd2/journal.c, 648): jbd2_log_wait_commit: JBD2: want 42104, j_commit_sequence=42103 (fs/jbd2/commit.c, 370): jbd2_journal_commit_transaction: JBD2: starting commit of transaction 42104 It is expected that this is not easy to replicate -- I was only able to cause it on preempt-rt kernels, and even then only under heavy I/O load. Reported-by: Paul Gortmaker Suggested-by: "Theodore Ts'o" Signed-off-by: Paul Gortmaker Signed-off-by: "Theodore Ts'o"

jbd2: optimize jbd2_journal_force_commit

2013-06-13T02:24:07Z

Current implementation of jbd2_journal_force_commit() is suboptimal because result in empty and useless commits. But callers just want to force and wait any unfinished commits. We already have jbd2_journal_force_commit_nested() which does exactly what we want, except we are guaranteed that we do not hold journal transaction open. Signed-off-by: Dmitry Monakhov Signed-off-by: "Theodore Ts'o"

jbd2: transaction reservation support

2013-06-04T16:35:11Z

In some cases we cannot start a transaction because of locking constraints and passing started transaction into those places is not handy either because we could block transaction commit for too long. Transaction reservation is designed to solve these issues. It reserves a handle with given number of credits in the journal and the handle can be later attached to the running transaction without blocking on commit or checkpointing. Reserved handles do not block transaction commit in any way, they only reduce maximum size of the running transaction (because we have to always be prepared to accomodate request for attaching reserved handle). Signed-off-by: Jan Kara Signed-off-by: "Theodore Ts'o"