user/sven/linux.git/include/linux/jbd.h, branch v3.3-rc6

jbd: Remove j_barrier mutex

2012-01-09T12:52:09Z

j_barrier mutex is used for serializing different journal lock operations. The problem with it is that e.g. FIFREEZE ioctl results in process leaving kernel with j_barrier mutex held which makes lockdep freak out. Also hibernation code wants to freeze filesystem but it cannot do so because it then cannot hibernate the system because of mutex being locked. So we remove j_barrier mutex and use direct wait on j_barrier_count instead. Since locking journal is a rare operation we don't have to care about fairness or such things. CC: Andrew Morton Acked-by: Joel Becker Signed-off-by: Jan Kara

jbd: clear revoked flag on buffers before a new transaction started

2011-11-22T00:20:53Z

Currently, we clear revoked flag only when a block is reused. However, this can tigger a false journal error. Consider a situation when a block is used as a meta block and is deleted(revoked) in ordered mode, then the block is allocated as a data block to a file. At this moment, user changes the file's journal mode from ordered to journaled and truncates the file. The block will be considered re-revoked by journal because it has revoked flag still pending from the last transaction and an assertion triggers. We fix the problem by keeping the revoked status more uptodate - we clear revoked flag when switching revoke tables to reflect there is no revoked buffers in current transaction any more. Signed-off-by: Yongqiang Yang Signed-off-by: Jan Kara

jdb/jbd2: factor out common functions from the jbd[2] header files

2011-10-27T08:38:18Z

The state bits and the lock functions of jbd and jbd2 are identical. Share them. Signed-off-by: Thomas Gleixner Signed-off-by: "Theodore Ts'o"

jbd: Fix oops in journal_remove_journal_head()

2011-06-27T09:44:37Z

journal_remove_journal_head() can oops when trying to access journal_head returned by bh2jh(). This is caused for example by the following race: TASK1 TASK2 journal_commit_transaction() ... processing t_forget list __journal_refile_buffer(jh); if (!jh->b_transaction) { jbd_unlock_bh_state(bh); journal_try_to_free_buffers() journal_grab_journal_head(bh) jbd_lock_bh_state(bh) __journal_try_to_free_buffer() journal_put_journal_head(jh) journal_remove_journal_head(bh); journal_put_journal_head() in TASK2 sees that b_jcount == 0 and buffer is not part of any transaction and thus frees journal_head before TASK1 gets to doing so. Note that even buffer_head can be released by try_to_free_buffers() after journal_put_journal_head() which adds even larger opportunity for oops (but I didn't see this happen in reality). Fix the problem by making transactions hold their own journal_head reference (in b_jcount). That way we don't have to remove journal_head explicitely via journal_remove_journal_head() and instead just remove journal_head when b_jcount drops to zero. The result of this is that [__]journal_refile_buffer(), [__]journal_unfile_buffer(), and __journal_remove_checkpoint() can free journal_head which needs modification of a few callers. Also we have to be careful because once journal_head is removed, buffer_head might be freed as well. So we have to get our own buffer_head reference where it matters. Signed-off-by: Jan Kara

jbd: Provide function to check whether transaction will issue data barrier

2010-05-21T17:30:40Z

Provide a function which returns whether a transaction with given tid will send a barrier to the filesystem device. The function will be used by ext3 to detect whether fsync needs to send a separate barrier or not. Signed-off-by: Jan Kara

include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

2010-03-30T13:02:32Z

percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo Guess-its-ok-by: Christoph Lameter Cc: Ingo Molnar Cc: Lee Schermerhorn

jbd[2]: remove references to BUFFER_DEBUG

2010-03-04T23:20:20Z

CONFIG_BUFFER_DEBUG seems to have been removed from the documentation somewhere around 2.4.15 and seemingly hasn't been available even longer. It is, however, still referenced at one place from the jbd code (one is a copy of the other header). Time to clean it up Signed-off-by: Christoph Egger Signed-off-by: Jan Kara

jbd.h: bitfields should be unsigned

2009-09-23T14:39:58Z

bitfields should be unsigned. This fixes sparse noise: error: dubious one-bit signed bitfield Signed-off-by: H Hartley Sweeten Cc: Jan Kara Cc: Theodore Ts'o Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

jbd: Journal block numbers can ever be only 32-bit use unsigned int for them

2009-09-16T15:44:10Z

It does not make sense to store block number for journal as unsigned long since they can be only 32-bit (because of on-disk format limitation). So change in-memory structures and variables to use unsigned int instead. Signed-off-by: Jan Kara

jbd: use SWRITE_SYNC_PLUG when writing synchronous revoke records

2009-04-14T14:10:47Z

The revoke records must be written using the same way as the rest of the blocks during the commit process; that is, either marked as synchronous writes or as asynchornous writes. Signed-off-by: "Theodore Ts'o"