linux/fs/ext4/fsync.c, branch v3.0

ext4: fix waiting and sending of a barrier in ext4_sync_file()

2011-05-24T16:00:54Z

jbd2_log_start_commit() returns 1 only when we really start a transaction. But we also need to wait for a transaction when the commit is already running. Fix this problem by waiting for transaction commit unconditionally (which is just a quick check if the transaction is already committed). Also we have to be more careful with sending of a barrier because when transaction is being committed in parallel to ext4_sync_file() running, we cannot be sure that the barrier the journalling code sends happens after we wrote all the data for fsync (note that not every data writeout needs to trigger metadata changes thus commit of some metadata changes can be running while other data is still written out). So use jbd2_will_send_data_barrier() helper to detect the common cases when we can be sure barrier will be issued by the commit code and issue the barrier ourselves in the remaining cases. Reported-by: Edward Goggin Signed-off-by: Jan Kara Signed-off-by: "Theodore Ts'o"

ext4: use EXT4FS_DEBUG instead of EXT4_DEBUG in fsync.c

2011-05-09T14:25:54Z

We have EXT4FS_DEBUG for some old debug and CONFIG_EXT4_DEBUG for the new mballoc debug, but there isn't any EXT4_DEBUG. As CONFIG_EXT4_DEBUG seems to be only used in mballoc, use EXT4FS_DEBUG in fsync.c. [ It doesn't really matter; although I'm including this commit for consistency's sake. The whole point of the #ifdef's is to disable the debugging code. In general you're not going to want to enable all of the code protected by EXT4FS_DEBUG at the same time. -- Ted ] Signed-off-by: Tao Ma Signed-off-by: "Theodore Ts'o"

Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

2011-04-11T22:45:47Z

* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: ext4: fix data corruption regression by reverting commit 6de9843dab3f ext4: Allow indirect-block file to grow the file size to max file size ext4: allow an active handle to be started when freezing ext4: sync the directory inode in ext4_sync_parent() ext4: init timer earlier to avoid a kernel panic in __save_error_info jbd2: fix potential memory leak on transaction commit ext4: fix a double free in ext4_register_li_request ext4: fix credits computing for indirect mapped files ext4: remove unnecessary [cm]time update of quota file jbd2: move bdget out of critical section

ext4: sync the directory inode in ext4_sync_parent()

2011-04-11T02:05:31Z

ext4 has taken the stance that, in the absence of a journal, when an fsync/fdatasync of an inode is done, the parent directory should be sync'ed if this inode entry is new. ext4_sync_parent(), which implements this, does indeed sync the dirent pages for parent directories, but it does not sync the directory *inode*. This patch fixes this. Also now return error status from ext4_sync_parent(). I tested this using a power fail test, which panics a machine running a file server getting requests from a client. Without this patch, on about every other test run, the server is missing many, many files that had been synced. With this patch, on > 6 runs, I see zero files being lost. Google-Bug-Id: 4179519 Signed-off-by: Curt Wohlgemuth Signed-off-by: "Theodore Ts'o"

Fix common misspellings

2011-03-31T14:26:23Z

Fixes generated by 'codespell' and manually reviewed. Signed-off-by: Lucas De Marchi

ext4: add more tracepoints and use dev_t in the trace buffer

2011-03-22T01:38:05Z

- Add more ext4 tracepoints. - Change ext4 tracepoints to use dev_t field with MAJOR/MINOR macros so that we can save 4 bytes in the ring buffer on some platforms. - Add sync_mode to ext4_da_writepages, ext4_da_write_pages, and ext4_da_writepages_result tracepoints. Also remove for_reclaim field from ext4_da_writepages since it is usually not very useful. Signed-off-by: Jiaying Zhang Signed-off-by: "Theodore Ts'o"

ext4: flush the i_completed_io_list during ext4_truncate

2011-01-10T17:47:05Z

Ted first found the bug when running 2.6.36 kernel with dioread_nolock mount option that xfstests #13 complained about wrong file size during fsck. However, the bug exists in the older kernels as well although it is somehow harder to trigger. The problem is that ext4_end_io_work() can happen after we have truncated an inode to a smaller size. Then when ext4_end_io_work() calls ext4_convert_unwritten_extents(), we may reallocate some blocks that have been truncated, so the inode size becomes inconsistent with the allocated blocks. The following patch flushes the i_completed_io_list during truncate to reduce the risk that some pending end_io requests are executed later and convert already truncated blocks to initialized. Note that although the fix helps reduce the problem a lot there may still be a race window between vmtruncate() and ext4_end_io_work(). The fundamental problem is that if vmtruncate() is called without either i_mutex or i_alloc_sem held, it can race with an ongoing write request so that the io_end request is processed later when the corresponding blocks have been truncated. Ted and I have discussed the problem offline and we saw a few ways to fix the race completely: a) We guarantee that i_mutex lock and i_alloc_sem write lock are both hold whenever vmtruncate() is called. The i_mutex lock prevents any new write requests from entering writeback and the i_alloc_sem prevents the race from ext4_page_mkwrite(). Currently we hold both locks if vmtruncate() is called from do_truncate(), which is probably the most common case. However, there are places where we may call vmtruncate() without holding either i_mutex or i_alloc_sem. I would like to ask for other people's opinions on what locks are expected to be held before calling vmtruncate(). There seems a disagreement among the callers of that function. b) We change the ext4 write path so that we change the extent tree to contain the newly allocated blocks and update i_size both at the same time --- when the write of the data blocks is completed. c) We add some additional locking to synchronize vmtruncate() and ext4_end_io_work(). This approach may have performance implications so we need to be careful. All of the above proposals may require more substantial changes, so we may consider to take the following patch as a bandaid. Signed-off-by: Jiaying Zhang Signed-off-by: "Theodore Ts'o"

Merge branch 'next' into upstream-merge

2010-10-28T03:44:47Z

Conflicts: fs/ext4/inode.c fs/ext4/mballoc.c include/trace/events/ext4.h

ext4: move flush_completed_IO to fs/ext4/fsync.c and make it static

2010-10-28T01:30:14Z

Fix a namespace leak by moving the function to the file where it is used and making it static. Signed-off-by: "Theodore Ts'o"

block: remove BLKDEV_IFL_WAIT

2010-09-16T18:52:58Z

All the blkdev_issue_* helpers can only sanely be used for synchronous caller. To issue cache flushes or barriers asynchronously the caller needs to set up a bio by itself with a completion callback to move the asynchronous state machine ahead. So drop the BLKDEV_IFL_WAIT flag that is always specified when calling blkdev_issue_* and also remove the now unused flags argument to blkdev_issue_flush and blkdev_issue_zeroout. For blkdev_issue_discard we need to keep it for the secure discard flag, which gains a more descriptive name and loses the bitops vs flag confusion. Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe