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* ext4: flush the i_completed_io_list during ext4_truncateJiaying Zhang2011-01-10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 <jiayingz@google.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
* Merge branch 'next' into upstream-mergeTheodore Ts'o2010-10-27
|\ | | | | | | | | | | | | 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 staticTheodore Ts'o2010-10-27
| | | | | | | | | | | | | | 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" <tytso@mit.edu>
* | block: remove BLKDEV_IFL_WAITChristoph Hellwig2010-09-16
|/ | | | | | | | | | | | | | 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 <hch@lst.de> Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
* rename the generic fsync implementationsChristoph Hellwig2010-05-27
| | | | | | | | | | | | | | | | We don't name our generic fsync implementations very well currently. The no-op implementation for in-memory filesystems currently is called simple_sync_file which doesn't make too much sense to start with, the the generic one for simple filesystems is called simple_fsync which can lead to some confusion. This patch renames the generic file fsync method to generic_file_fsync to match the other generic_file_* routines it is supposed to be used with, and the no-op implementation to noop_fsync to make it obvious what to expect. In addition add some documentation for both methods. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* drop unused dentry argument to ->fsyncChristoph Hellwig2010-05-27
| | | | | Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* Merge branch 'for_linus' of ↵Linus Torvalds2010-05-27
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4 * 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (40 commits) ext4: Make fsync sync new parent directories in no-journal mode ext4: Drop whitespace at end of lines ext4: Fix compat EXT4_IOC_ADD_GROUP ext4: Conditionally define compat ioctl numbers tracing: Convert more ext4 events to DEFINE_EVENT ext4: Add new tracepoints to track mballoc's buddy bitmap loads ext4: Add a missing trace hook ext4: restart ext4_ext_remove_space() after transaction restart ext4: Clear the EXT4_EOFBLOCKS_FL flag only when warranted ext4: Avoid crashing on NULL ptr dereference on a filesystem error ext4: Use bitops to read/modify i_flags in struct ext4_inode_info ext4: Convert calls of ext4_error() to EXT4_ERROR_INODE() ext4: Convert callers of ext4_get_blocks() to use ext4_map_blocks() ext4: Add new abstraction ext4_map_blocks() underneath ext4_get_blocks() ext4: Use our own write_cache_pages() ext4: Show journal_checksum option ext4: Fix for ext4_mb_collect_stats() ext4: check for a good block group before loading buddy pages ext4: Prevent creation of files larger than RLIMIT_FSIZE using fallocate ext4: Remove extraneous newlines in ext4_msg() calls ... Fixed up trivial conflict in fs/ext4/fsync.c
| * ext4: Make fsync sync new parent directories in no-journal modeFrank Mayhar2010-05-17
| | | | | | | | | | | | | | | | | | | | | | | | | | Add a new ext4 state to tell us when a file has been newly created; use that state in ext4_sync_file in no-journal mode to tell us when we need to sync the parent directory as well as the inode and data itself. This fixes a problem in which a panic or power failure may lose the entire file even when using fsync, since the parent directory entry is lost. Addresses-Google-Bug: #2480057 Signed-off-by: Frank Mayhar <fmayhar@google.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
| * ext4: Drop whitespace at end of linesTheodore Ts'o2010-05-17
| | | | | | | | | | | | | | | | | | | | | | | | This patch was generated using: #!/usr/bin/perl -i while (<>) { s/[ ]+$//; print; } Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
| * ext4: check missed return value in ext4_sync_file()Dmitry Monakhov2010-05-10
| | | | | | | | | | Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
* | blkdev: generalize flags for blkdev_issue_fn functionsDmitry Monakhov2010-04-28
|/ | | | | | | | The patch just convert all blkdev_issue_xxx function to common set of flags. Wait/allocation semantics preserved. Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
* ext4: mechanical rename some of the direct I/O get_block's identifiersJiaying Zhang2010-03-02
| | | | | | | | | | | This commit renames some of the direct I/O's block allocation flags, variables, and functions introduced in Mingming's "Direct IO for holes and fallocate" patches so that they can be used by ext4's buffered write path as well. Also changed the related function comments accordingly to cover both direct write and buffered write cases. Signed-off-by: Jiaying Zhang <jiayingz@google.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
* ext4, jbd2: Add barriers for file systems with exernal journalsTheodore Ts'o2009-12-23
| | | | | | | | | | | | | | | | | | | | This is a bit complicated because we are trying to optimize when we send barriers to the fs data disk. We could just throw in an extra barrier to the data disk whenever we send a barrier to the journal disk, but that's not always strictly necessary. We only need to send a barrier during a commit when there are data blocks which are must be written out due to an inode written in ordered mode, or if fsync() depends on the commit to force data blocks to disk. Finally, before we drop transactions from the beginning of the journal during a checkpoint operation, we need to guarantee that any blocks that were flushed out to the data disk are firmly on the rust platter before we drop the transaction from the journal. Thanks to Oleg Drokin for pointing out this flaw in ext3/ext4. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
* ext4: Wait for proper transaction commit on fsyncJan Kara2009-12-08
| | | | | | | | | | | We cannot rely on buffer dirty bits during fsync because pdflush can come before fsync is called and clear dirty bits without forcing a transaction commit. What we do is that we track which transaction has last changed the inode and which transaction last changed allocation and force it to disk on fsync. Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
* ext4: avoid issuing unnecessary barriersTheodore Ts'o2009-11-23
| | | | | | | | | We don't to issue an I/O barrier on an error or if we force commit because we are doing data journaling. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Cc: Jan Kara <jack@suse.cz> Cc: stable@kernel.org
* ext4: async direct IO for holes and fallocate supportMingming Cao2009-09-28
| | | | | | | | | | | | | | | | For async direct IO that covers holes or fallocate, the end_io callback function now queued the convertion work on workqueue but don't flush the work rightaway as it might take too long to afford. But when fsync is called after all the data is completed, user expects the metadata also being updated before fsync returns. Thus we need to flush the conversion work when fsync() is called. This patch keep track of a listed of completed async direct io that has a work queued on workqueue. When fsync() is called, it will go through the list and do the conversion. Signed-off-by: Mingming Cao <cmm@us.ibm.com>
* ext4: Assure that metadata blocks are written during fsync in no journal modeTheodore Ts'o2009-09-12
| | | | | | | | | | | When there is no journal present, we must attach buffer heads associated with extent tree and indirect blocks to the inode's mapping->private_list via mark_buffer_dirty_inode() so that ext4_sync_file() --- which is called to service fsync() and fdatasync() system calls --- can write out the inode's metadata blocks by calling sync_mapping_buffers(). Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
* ext4: fix cache flush in ext4_sync_fileChristoph Hellwig2009-09-05
| | | | | | | | | | | | | We need to flush the write cache unconditionally in ->fsync, otherwise writes into already allocated blocks can get lost. Writes into fully allocated files are very common when using disk images for virtualization, and without this fix can easily lose data after an fdatasync, which is the typical implementation for a cache flush on the virtual drive. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Eric Sandeen <sandeen@redhat.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
* ext4: convert instrumentation from markers to tracepointsTheodore Ts'o2009-06-17
| | | | Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
* ext4: Add debugging markers that can be used by systemtapTheodore Ts'o2008-10-05
| | | | | | | This debugging markers are designed to debug problems such as the random filesystem latency problems reported by Arjan. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
* ext4: Fix whitespace checkpatch warnings/errorsTheodore Ts'o2008-09-08
| | | | | Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
* ext4: call blkdev_issue_flush on fsyncEric Sandeen2008-07-11
| | | | | | | | | | | | To ensure that bits are truly on-disk after an fsync, we should call blkdev_issue_flush if barriers are supported. Inspired by an old thread on barriers, by reiserfs & xfs which do the same, and by a patch SuSE ships with their kernel Signed-off-by: Eric Sandeen <sandeen@redhat.com> Signed-off-by: Mingming Cao <cmm@us.ibm.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
* ext4: move headers out of include/linuxChristoph Hellwig2008-04-29
| | | | | | | | | | Move ext4 headers out of include/linux. This is just the trivial move, there's some more thing that could be done later. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Mingming Cao <cmm@us.ibm.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
* ext4: fdatasync should skip metadata writeout when overwritingHisashi Hifumi2008-04-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently fdatasync is identical to fsync in ext3. I think fdatasync should skip journal flush in data=ordered and data=writeback mode when it overwrites to already-instantiated blocks on HDD. When I_DIRTY_DATASYNC flag is not set, fdatasync should skip journal writeout because this indicates only atime or/and mtime updates. Following patch is the same approach of ext2's fsync code(ext2_sync_file). I did a performance test using the sysbench. #sysbench --num-threads=128 --max-requests=50000 --test=fileio --file-total-size=128G --file-test-mode=rndwr --file-fsync-mode=fdatasync run The result on ext3 was: -2.6.24 Operations performed: 0 Read, 50080 Write, 59600 Other = 109680 Total Read 0b Written 782.5Mb Total transferred 782.5Mb (12.116Mb/sec) 775.45 Requests/sec executed Test execution summary: total time: 64.5814s total number of events: 50080 total time taken by event execution: 3713.9836 per-request statistics: min: 0.0000s avg: 0.0742s max: 0.9375s approx. 95 percentile: 0.2901s Threads fairness: events (avg/stddev): 391.2500/23.26 execution time (avg/stddev): 29.0155/1.99 -2.6.24-patched Operations performed: 0 Read, 50009 Write, 61596 Other = 111605 Total Read 0b Written 781.39Mb Total transferred 781.39Mb (16.419Mb/sec) 1050.83 Requests/sec executed Test execution summary: total time: 47.5900s total number of events: 50009 total time taken by event execution: 2934.5768 per-request statistics: min: 0.0000s avg: 0.0587s max: 0.8938s approx. 95 percentile: 0.1993s Threads fairness: events (avg/stddev): 390.6953/22.64 execution time (avg/stddev): 22.9264/1.17 Filesystem I/O throughput was improved. Signed-off-by :Hisashi Hifumi <hifumi.hisashi@oss.ntt.co.jp> Acked-by: Jan Kara <jack@suse.cz> Cc: <linux-ext4@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
* ext4: sparse fixesAneesh Kumar K.V2007-10-17
| | | | Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
* [PATCH] jbd2: enable building of jbd2 and have ext4 use it rather than jbdMingming Cao2006-10-11
| | | | | | | | | | Reworked from a patch by Mingming Cao and Randy Dunlap Signed-off-By: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Mingming Cao <cmm@us.ibm.com> Signed-off-by: Dave Kleikamp <shaggy@austin.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] ext4: rename ext4 symbols to avoid duplication of ext3 symbolsMingming Cao2006-10-11
| | | | | | | | | | Mingming Cao originally did this work, and Shaggy reproduced it using some scripts from her. Signed-off-by: Mingming Cao <cmm@us.ibm.com> Signed-off-by: Dave Kleikamp <shaggy@austin.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] ext4: initial copy of files from ext3Dave Kleikamp2006-10-11
Start of the ext4 patch series. See Documentation/filesystems/ext4.txt for details. This is a simple copy of the files in fs/ext3 to fs/ext4 and /usr/incude/linux/ext3* to /usr/include/ex4* Signed-off-by: Dave Kleikamp <shaggy@austin.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>