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path: root/fs/btrfs/inode.c
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2014-05-06switch {__,}blockdev_direct_IO() to iov_iterAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-05-06get rid of pointless iov_length() in ->direct_IO()Al Viro
all callers have iov_length(iter->iov, iter->nr_segs) == iov_iter_count(iter) Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-05-06pass iov_iter to ->direct_IO()Al Viro
unmodified, for now Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-04-11Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs Pull second set of btrfs updates from Chris Mason: "The most important changes here are from Josef, fixing a btrfs regression in 3.14 that can cause corruptions in the extent allocation tree when snapshots are in use. Josef also fixed some deadlocks in send/recv and other assorted races when balance is running" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (23 commits) Btrfs: fix compile warnings on on avr32 platform btrfs: allow mounting btrfs subvolumes with different ro/rw options btrfs: export global block reserve size as space_info btrfs: fix crash in remount(thread_pool=) case Btrfs: abort the transaction when we don't find our extent ref Btrfs: fix EINVAL checks in btrfs_clone Btrfs: fix unlock in __start_delalloc_inodes() Btrfs: scrub raid56 stripes in the right way Btrfs: don't compress for a small write Btrfs: more efficient io tree navigation on wait_extent_bit Btrfs: send, build path string only once in send_hole btrfs: filter invalid arg for btrfs resize Btrfs: send, fix data corruption due to incorrect hole detection Btrfs: kmalloc() doesn't return an ERR_PTR Btrfs: fix snapshot vs nocow writting btrfs: Change the expanding write sequence to fix snapshot related bug. btrfs: make device scan less noisy btrfs: fix lockdep warning with reclaim lock inversion Btrfs: hold the commit_root_sem when getting the commit root during send Btrfs: remove transaction from send ...
2014-04-07Btrfs: fix unlock in __start_delalloc_inodes()Wang Shilong
This patch fix a regression caused by the following patch: Btrfs: don't flush all delalloc inodes when we doesn't get s_umount lock break while loop will make us call @spin_unlock() without calling @spin_lock() before, fix it. Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com> Reviewed-by: David Sterba <dsterba@suse.cz> Signed-off-by: Chris Mason <clm@fb.com>
2014-04-07Btrfs: don't compress for a small writeWang Shilong
To compress a small file range(<=blocksize) that is not an inline extent can not save disk space at all. skip it can save us some cpu time. This patch can also fix wrong setting nocompression flag for inode, say a case when @total_in is 4096, and then we get @total_compressed 52,because we do aligment to page cache size firstly, and then we get into conclusion @total_in=@total_compressed thus we will clear this inode's compression flag. An exception comes from inserting inline extent failure but we still have @total_compressed < @total_in,so we will still reset inode's flag, this is ok, because we don't have good compression effect. Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com> Signed-off-by: Chris Mason <clm@fb.com>
2014-04-07Btrfs: fix snapshot vs nocow writtingWang Shilong
While running fsstress and snapshots concurrently, we will hit something like followings: Thread 1 Thread 2 |->fallocate |->write pages |->join transaction |->add ordered extent |->end transaction |->flushing data |->creating pending snapshots |->write data into src root's fallocated space After above work flows finished, we will get a state that source and snapshot root share same space, but source root have written data into fallocated space, this will make fsck fail to verify checksums for snapshot root's preallocating file extent data.Nocow writting also has this same problem. Fix this problem by syncing snapshots with nocow writting: 1.for nocow writting,if there are pending snapshots, we will fall into COW way. 2.if there are pending nocow writes, snapshots for this root will be blocked until nocow writting finish. Reported-by: Gui Hecheng <guihc.fnst@cn.fujitsu.com> Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com> Signed-off-by: Chris Mason <clm@fb.com>
2014-04-04Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs Pull btrfs changes from Chris Mason: "This is a pretty long stream of bug fixes and performance fixes. Qu Wenruo has replaced the btrfs async threads with regular kernel workqueues. We'll keep an eye out for performance differences, but it's nice to be using more generic code for this. We still have some corruption fixes and other patches coming in for the merge window, but this batch is tested and ready to go" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (108 commits) Btrfs: fix a crash of clone with inline extents's split btrfs: fix uninit variable warning Btrfs: take into account total references when doing backref lookup Btrfs: part 2, fix incremental send's decision to delay a dir move/rename Btrfs: fix incremental send's decision to delay a dir move/rename Btrfs: remove unnecessary inode generation lookup in send Btrfs: fix race when updating existing ref head btrfs: Add trace for btrfs_workqueue alloc/destroy Btrfs: less fs tree lock contention when using autodefrag Btrfs: return EPERM when deleting a default subvolume Btrfs: add missing kfree in btrfs_destroy_workqueue Btrfs: cache extent states in defrag code path Btrfs: fix deadlock with nested trans handles Btrfs: fix possible empty list access when flushing the delalloc inodes Btrfs: split the global ordered extents mutex Btrfs: don't flush all delalloc inodes when we doesn't get s_umount lock Btrfs: reclaim delalloc metadata more aggressively Btrfs: remove unnecessary lock in may_commit_transaction() Btrfs: remove the unnecessary flush when preparing the pages Btrfs: just do dirty page flush for the inode with compression before direct IO ...
2014-04-03mm + fs: store shadow entries in page cacheJohannes Weiner
Reclaim will be leaving shadow entries in the page cache radix tree upon evicting the real page. As those pages are found from the LRU, an iput() can lead to the inode being freed concurrently. At this point, reclaim must no longer install shadow pages because the inode freeing code needs to ensure the page tree is really empty. Add an address_space flag, AS_EXITING, that the inode freeing code sets under the tree lock before doing the final truncate. Reclaim will check for this flag before installing shadow pages. Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Rik van Riel <riel@redhat.com> Reviewed-by: Minchan Kim <minchan@kernel.org> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Bob Liu <bob.liu@oracle.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Dave Chinner <david@fromorbit.com> Cc: Greg Thelen <gthelen@google.com> Cc: Hugh Dickins <hughd@google.com> Cc: Jan Kara <jack@suse.cz> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Luigi Semenzato <semenzato@google.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Metin Doslu <metin@citusdata.com> Cc: Michel Lespinasse <walken@google.com> Cc: Ozgun Erdogan <ozgun@citusdata.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Roman Gushchin <klamm@yandex-team.ru> Cc: Ryan Mallon <rmallon@gmail.com> Cc: Tejun Heo <tj@kernel.org> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-03-10Btrfs: fix possible empty list access when flushing the delalloc inodesMiao Xie
We didn't have a lock to protect the access to the delalloc inodes list, that is we might access a empty delalloc inodes list if someone start flushing delalloc inodes because the delalloc inodes were moved into a other list temporarily. Fix it by wrapping the access with a lock. Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10Btrfs: don't flush all delalloc inodes when we doesn't get s_umount lockMiao Xie
We needn't flush all delalloc inodes when we doesn't get s_umount lock, or we would make the tasks wait for a long time. Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10Btrfs: just do dirty page flush for the inode with compression before direct IOMiao Xie
As the comment in the btrfs_direct_IO says, only the compressed pages need be flush again to make sure they are on the disk, but the common pages needn't, so we add a if statement to check if the inode has compressed pages or not, if no, skip the flush. And in order to prevent the write ranges from intersecting, we need wait for the running ordered extents. But the current code waits for them twice, one is done before the direct IO starts (in btrfs_wait_ordered_range()), the other is before we get the blocks, it is unnecessary. because we can do the direct IO without holding i_mutex, it means that the intersected ordered extents may happen during the direct IO, the first wait can not avoid this problem. So we use filemap_fdatawrite_range() instead of btrfs_wait_ordered_range() to remove the first wait. Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10btrfs: Cleanup the "_struct" suffix in btrfs_workequeueQu Wenruo
Since the "_struct" suffix is mainly used for distinguish the differnt btrfs_work between the original and the newly created one, there is no need using the suffix since all btrfs_workers are changed into btrfs_workqueue. Also this patch fixed some codes whose code style is changed due to the too long "_struct" suffix. Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com> Tested-by: David Sterba <dsterba@suse.cz> Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10btrfs: Replace fs_info->fixup_workers workqueue with btrfs_workqueue.Qu Wenruo
Replace the fs_info->fixup_workers with the newly created btrfs_workqueue. Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com> Tested-by: David Sterba <dsterba@suse.cz> Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10btrfs: Replace fs_info->endio_* workqueue with btrfs_workqueue.Qu Wenruo
Replace the fs_info->endio_* workqueues with the newly created btrfs_workqueue. Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com> Tested-by: David Sterba <dsterba@suse.cz> Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10btrfs: Replace fs_info->flush_workers with btrfs_workqueue.Qu Wenruo
Replace the fs_info->submit_workers with the newly created btrfs_workqueue. Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com> Tested-by: David Sterba <dsterba@suse.cz> Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10btrfs: Replace fs_info->delalloc_workers with btrfs_workqueueQu Wenruo
Much like the fs_info->workers, replace the fs_info->delalloc_workers use the same btrfs_workqueue. Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com> Tested-by: David Sterba <dsterba@suse.cz> Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10Btrfs: fix preallocate vs double nocow writeMiao Xie
We can not release the reserved metadata space for the first write if we find the write position is pre-allocated. Because the kernel might write the data on the disk before we do the second write but after the can-nocow check, if we release the space for the first write, we might fail to update the metadata because of no space. Fix this problem by end nocow write if there is dirty data in the range whose space is pre-allocated. Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10Btrfs: avoid warning bomb of btrfs_invalidate_inodesLiu Bo
So after transaction is aborted, we need to cleanup inode resources by calling btrfs_invalidate_inodes(), and btrfs_invalidate_inodes() hopes roots' refs to be zero in old times and sets a WARN_ON(), however, this is not always true within cleaning up transaction, so we get to detect transaction abortion and not warn at all. Signed-off-by: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10Btrfs: skip readonly root for snapshot-aware defragmentWang Shilong
Btrfs send is assuming readonly root won't change, let's skip readonly root. Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com> Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10Btrfs: unlock extent and pages on error in cow_file_rangeJosef Bacik
When I converted the BUG_ON() for the free_space_cache_inode in cow_file_range I made it so we just return an error instead of unlocking all of our various stuff. This is a mistake and causes us to hang when we run into this. This patch fixes this problem. Thanks, Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10Btrfs: balance delayed inode updatesJosef Bacik
While trying to reproduce a delayed ref problem I noticed the box kept falling over using all 80gb of my ram with btrfs_inode's and btrfs_delayed_node's. Turns out this is because we only throttle delayed inode updates in btrfs_dirty_inode, which doesn't actually get called that often, especially when all you are doing is creating a bunch of files. So balance delayed inode updates everytime we create a new inode. With this patch we no longer use up all of our ram with delayed inode updates. Thanks, Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-02-16Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs Pull btrfs fixes from Chris Mason: "We have a small collection of fixes in my for-linus branch. The big thing that stands out is a revert of a new ioctl. Users haven't shipped yet in btrfs-progs, and Dave Sterba found a better way to export the information" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: Btrfs: use right clone root offset for compressed extents btrfs: fix null pointer deference at btrfs_sysfs_add_one+0x105 Btrfs: unset DCACHE_DISCONNECTED when mounting default subvol Btrfs: fix max_inline mount option Btrfs: fix a lockdep warning when cleaning up aborted transaction Revert "btrfs: add ioctl to export size of global metadata reservation"
2014-02-14Btrfs: unset DCACHE_DISCONNECTED when mounting default subvolJosef Bacik
A user was running into errors from an NFS export of a subvolume that had a default subvol set. When we mount a default subvol we will use d_obtain_alias() to find an existing dentry for the subvolume in the case that the root subvol has already been mounted, or a dummy one is allocated in the case that the root subvol has not already been mounted. This allows us to connect the dentry later on if we wander into the path. However if we don't ever wander into the path we will keep DCACHE_DISCONNECTED set for a long time, which angers NFS. It doesn't appear to cause any problems but it is annoying nonetheless, so simply unset DCACHE_DISCONNECTED in the get_default_root case and switch btrfs_lookup() to use d_materialise_unique() instead which will make everything play nicely together and reconnect stuff if we wander into the defaul subvol path from a different way. With this patch I'm no longer getting the NFS errors when exporting a volume that has been mounted with a default subvol set. Thanks, cc: bfields@fieldses.org cc: ebiederm@xmission.com Signed-off-by: Josef Bacik <jbacik@fb.com> Acked-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Chris Mason <clm@fb.com>
2014-02-04Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs Pull btrfs fixes from Chris Mason: "Filipe is fixing compile and boot problems with our crc32c rework, and Josef has disabled snapshot aware defrag for now. As the number of snapshots increases, we're hitting OOM. For the short term we're disabling things until a bigger fix is ready" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: Btrfs: use late_initcall instead of module_init Btrfs: use btrfs_crc32c everywhere instead of libcrc32c Btrfs: disable snapshot aware defrag for now
2014-02-03Btrfs: disable snapshot aware defrag for nowJosef Bacik
It's just broken and it's taking a lot of effort to fix it, so for now just disable it so people can defrag in peace. Thanks, Cc: stable@vger.kernel.org Signed-off-by: Josef Bacik <jbacik@fb.com> Signed-off-by: Chris Mason <clm@fb.com>
2014-01-30Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs Pull btrfs updates from Chris Mason: "This is a pretty big pull, and most of these changes have been floating in btrfs-next for a long time. Filipe's properties work is a cool building block for inheriting attributes like compression down on a per inode basis. Jeff Mahoney kicked in code to export filesystem info into sysfs. Otherwise, lots of performance improvements, cleanups and bug fixes. Looks like there are still a few other small pending incrementals, but I wanted to get the bulk of this in first" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (149 commits) Btrfs: fix spin_unlock in check_ref_cleanup Btrfs: setup inode location during btrfs_init_inode_locked Btrfs: don't use ram_bytes for uncompressed inline items Btrfs: fix btrfs_search_slot_for_read backwards iteration Btrfs: do not export ulist functions Btrfs: rework ulist with list+rb_tree Btrfs: fix memory leaks on walking backrefs failure Btrfs: fix send file hole detection leading to data corruption Btrfs: add a reschedule point in btrfs_find_all_roots() Btrfs: make send's file extent item search more efficient Btrfs: fix to catch all errors when resolving indirect ref Btrfs: fix protection between walking backrefs and root deletion btrfs: fix warning while merging two adjacent extents Btrfs: fix infinite path build loops in incremental send btrfs: undo sysfs when open_ctree() fails Btrfs: fix snprintf usage by send's gen_unique_name btrfs: fix defrag 32-bit integer overflow btrfs: sysfs: list the NO_HOLES feature btrfs: sysfs: don't show reserved incompat feature btrfs: call permission checks earlier in ioctls and return EPERM ...
2014-01-30Merge branch 'for-3.14/core' of git://git.kernel.dk/linux-blockLinus Torvalds
Pull core block IO changes from Jens Axboe: "The major piece in here is the immutable bio_ve series from Kent, the rest is fairly minor. It was supposed to go in last round, but various issues pushed it to this release instead. The pull request contains: - Various smaller blk-mq fixes from different folks. Nothing major here, just minor fixes and cleanups. - Fix for a memory leak in the error path in the block ioctl code from Christian Engelmayer. - Header export fix from CaiZhiyong. - Finally the immutable biovec changes from Kent Overstreet. This enables some nice future work on making arbitrarily sized bios possible, and splitting more efficient. Related fixes to immutable bio_vecs: - dm-cache immutable fixup from Mike Snitzer. - btrfs immutable fixup from Muthu Kumar. - bio-integrity fix from Nic Bellinger, which is also going to stable" * 'for-3.14/core' of git://git.kernel.dk/linux-block: (44 commits) xtensa: fixup simdisk driver to work with immutable bio_vecs block/blk-mq-cpu.c: use hotcpu_notifier() blk-mq: for_each_* macro correctness block: Fix memory leak in rw_copy_check_uvector() handling bio-integrity: Fix bio_integrity_verify segment start bug block: remove unrelated header files and export symbol blk-mq: uses page->list incorrectly blk-mq: use __smp_call_function_single directly btrfs: fix missing increment of bi_remaining Revert "block: Warn and free bio if bi_end_io is not set" block: Warn and free bio if bi_end_io is not set blk-mq: fix initializing request's start time block: blk-mq: don't export blk_mq_free_queue() block: blk-mq: make blk_sync_queue support mq block: blk-mq: support draining mq queue dm cache: increment bi_remaining when bi_end_io is restored block: fixup for generic bio chaining block: Really silence spurious compiler warnings block: Silence spurious compiler warnings block: Kill bio_pair_split() ...
2014-01-29Btrfs: setup inode location during btrfs_init_inode_lockedChris Mason
We have a race during inode init because the BTRFS_I(inode)->location is setup after the inode hash table lock is dropped. btrfs_find_actor uses the location field, so our search might not find an existing inode in the hash table if we race with the inode init code. This commit changes things to setup the location field sooner. Also the find actor now uses only the location objectid to match inodes. For inode hashing, we just need a unique and stable test, it doesn't have to reflect the inode numbers we show to userland. Signed-off-by: Chris Mason <clm@fb.com> CC: stable@vger.kernel.org
2014-01-29Btrfs: don't use ram_bytes for uncompressed inline itemsChris Mason
If we truncate an uncompressed inline item, ram_bytes isn't updated to reflect the new size. The fixe uses the size directly from the item header when reading uncompressed inlines, and also fixes truncate to update the size as it goes. Reported-by: Jens Axboe <axboe@fb.com> Signed-off-by: Chris Mason <clm@fb.com> CC: stable@vger.kernel.org
2014-01-29btrfs: fix warning while merging two adjacent extentsGui Hecheng
When we have two adjacent extents in relink_extent_backref, we try to merge them. When we use btrfs_search_slot to locate the slot for the current extent, we shouldn't set "ins_len = 1", because we will merge it into the previous extent rather than insert a new item. Otherwise, we may happen to create a new leaf in btrfs_search_slot and path->slot[0] will be 0. Then we try to fetch the previous item using "path->slots[0]--", and it will cause a warning as follows: [ 145.713385] WARNING: CPU: 3 PID: 1796 at fs/btrfs/extent_io.c:5043 map_private_extent_buffer+0xd4/0xe0 [ 145.713387] btrfs bad mapping eb start 5337088 len 4096, wanted 167772306 8 ... [ 145.713462] [<ffffffffa034b1f4>] map_private_extent_buffer+0xd4/0xe0 [ 145.713476] [<ffffffffa030097a>] ? btrfs_free_path+0x2a/0x40 [ 145.713485] [<ffffffffa0340864>] btrfs_get_token_64+0x64/0xf0 [ 145.713498] [<ffffffffa033472c>] relink_extent_backref+0x41c/0x820 [ 145.713508] [<ffffffffa0334d69>] btrfs_finish_ordered_io+0x239/0xa80 I encounter this warning when running defrag having mkfs.btrfs with option -M. At the same time there are read/writes & snapshots running at background. Signed-off-by: Gui Hecheng <guihc.fnst@cn.fujitsu.com> Reviewed-by: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: Josef Bacik <jbacik@fb.com> Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28Btrfs: fix transaction abortion when remounting btrfs from RW to ROWang Shilong
Steps to reproduce: # mkfs.btrfs -f /dev/sda8 # mount /dev/sda8 /mnt -o flushoncommit # dd if=/dev/zero of=/mnt/data bs=4k count=102400 & # mount /dev/sda8 /mnt -o remount, ro When remounting RW to RO, the logic is to firstly set flag to RO and then commit transaction, however with option flushoncommit enabled,we will do RO check within committing transaction, so we get a transaction abortion here. Actually,here check is wrong, we should check if FS_STATE_ERROR is set, fix it. Reported-by: Qu Wenruo <quwenruo@cn.fujitsu.com> Suggested-by: Miao Xie <miaox@cn.fujitsu.com> Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com> Signed-off-by: Josef Bacik <jbacik@fb.com> Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28Btrfs: add support for inode propertiesFilipe David Borba Manana
This change adds infrastructure to allow for generic properties for inodes. Properties are name/value pairs that can be associated with inodes for different purposes. They are stored as xattrs with the prefix "btrfs." Properties can be inherited - this means when a directory inode has inheritable properties set, these are added to new inodes created under that directory. Further, subvolumes can also have properties associated with them, and they can be inherited from their parent subvolume. Naturally, directory properties have priority over subvolume properties (in practice a subvolume property is just a regular property associated with the root inode, objectid 256, of the subvolume's fs tree). This change also adds one specific property implementation, named "compression", whose values can be "lzo" or "zlib" and it's an inheritable property. The corresponding changes to btrfs-progs were also implemented. A patch with xfstests for this feature will follow once there's agreement on this change/feature. Further, the script at the bottom of this commit message was used to do some benchmarks to measure any performance penalties of this feature. Basically the tests correspond to: Test 1 - create a filesystem and mount it with compress-force=lzo, then sequentially create N files of 64Kb each, measure how long it took to create the files, unmount the filesystem, mount the filesystem and perform an 'ls -lha' against the test directory holding the N files, and report the time the command took. Test 2 - create a filesystem and don't use any compression option when mounting it - instead set the compression property of the subvolume's root to 'lzo'. Then create N files of 64Kb, and report the time it took. The unmount the filesystem, mount it again and perform an 'ls -lha' like in the former test. This means every single file ends up with a property (xattr) associated to it. Test 3 - same as test 2, but uses 4 properties - 3 are duplicates of the compression property, have no real effect other than adding more work when inheriting properties and taking more btree leaf space. Test 4 - same as test 3 but with 10 properties per file. Results (in seconds, and averages of 5 runs each), for different N numbers of files follow. * Without properties (test 1) file creation time ls -lha time 10 000 files 3.49 0.76 100 000 files 47.19 8.37 1 000 000 files 518.51 107.06 * With 1 property (compression property set to lzo - test 2) file creation time ls -lha time 10 000 files 3.63 0.93 100 000 files 48.56 9.74 1 000 000 files 537.72 125.11 * With 4 properties (test 3) file creation time ls -lha time 10 000 files 3.94 1.20 100 000 files 52.14 11.48 1 000 000 files 572.70 142.13 * With 10 properties (test 4) file creation time ls -lha time 10 000 files 4.61 1.35 100 000 files 58.86 13.83 1 000 000 files 656.01 177.61 The increased latencies with properties are essencialy because of: *) When creating an inode, we now synchronously write 1 more item (an xattr item) for each property inherited from the parent dir (or subvolume). This could be done in an asynchronous way such as we do for dir intex items (delayed-inode.c), which could help reduce the file creation latency; *) With properties, we now have larger fs trees. For this particular test each xattr item uses 75 bytes of leaf space in the fs tree. This could be less by using a new item for xattr items, instead of the current btrfs_dir_item, since we could cut the 'location' and 'type' fields (saving 18 bytes) and maybe 'transid' too (saving a total of 26 bytes per xattr item) from the btrfs_dir_item type. Also tried batching the xattr insertions (ignoring proper hash collision handling, since it didn't exist) when creating files that inherit properties from their parent inode/subvolume, but the end results were (surprisingly) essentially the same. Test script: $ cat test.pl #!/usr/bin/perl -w use strict; use Time::HiRes qw(time); use constant NUM_FILES => 10_000; use constant FILE_SIZES => (64 * 1024); use constant DEV => '/dev/sdb4'; use constant MNT_POINT => '/home/fdmanana/btrfs-tests/dev'; use constant TEST_DIR => (MNT_POINT . '/testdir'); system("mkfs.btrfs", "-l", "16384", "-f", DEV) == 0 or die "mkfs.btrfs failed!"; # following line for testing without properties #system("mount", "-o", "compress-force=lzo", DEV, MNT_POINT) == 0 or die "mount failed!"; # following 2 lines for testing with properties system("mount", DEV, MNT_POINT) == 0 or die "mount failed!"; system("btrfs", "prop", "set", MNT_POINT, "compression", "lzo") == 0 or die "set prop failed!"; system("mkdir", TEST_DIR) == 0 or die "mkdir failed!"; my ($t1, $t2); $t1 = time(); for (my $i = 1; $i <= NUM_FILES; $i++) { my $p = TEST_DIR . '/file_' . $i; open(my $f, '>', $p) or die "Error opening file!"; $f->autoflush(1); for (my $j = 0; $j < FILE_SIZES; $j += 4096) { print $f ('A' x 4096) or die "Error writing to file!"; } close($f); } $t2 = time(); print "Time to create " . NUM_FILES . ": " . ($t2 - $t1) . " seconds.\n"; system("umount", DEV) == 0 or die "umount failed!"; system("mount", DEV, MNT_POINT) == 0 or die "mount failed!"; $t1 = time(); system("bash -c 'ls -lha " . TEST_DIR . " > /dev/null'") == 0 or die "ls failed!"; $t2 = time(); print "Time to ls -lha all files: " . ($t2 - $t1) . " seconds.\n"; system("umount", DEV) == 0 or die "umount failed!"; Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com> Signed-off-by: Josef Bacik <jbacik@fb.com> Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28Btrfs: faster file extent item replace operationsFilipe David Borba Manana
When writing to a file we drop existing file extent items that cover the write range and then add a new file extent item that represents that write range. Before this change we were doing a tree lookup to remove the file extent items, and then after we did another tree lookup to insert the new file extent item. Most of the time all the file extent items we need to drop are located within a single leaf - this is the leaf where our new file extent item ends up at. Therefore, in this common case just combine these 2 operations into a single one. By avoiding the second btree navigation for insertion of the new file extent item, we reduce btree node/leaf lock acquisitions/releases, btree block/leaf COW operations, CPU time on btree node/leaf key binary searches, etc. Besides for file writes, this is an operation that happens for file fsync's as well. However log btrees are much less likely to big as big as regular fs btrees, therefore the impact of this change is smaller. The following benchmark was performed against an SSD drive and a HDD drive, both for random and sequential writes: sysbench --test=fileio --file-num=4096 --file-total-size=8G \ --file-test-mode=[rndwr|seqwr] --num-threads=512 \ --file-block-size=8192 \ --max-requests=1000000 \ --file-fsync-freq=0 --file-io-mode=sync [prepare|run] All results below are averages of 10 runs of the respective test. ** SSD sequential writes Before this change: 225.88 Mb/sec After this change: 277.26 Mb/sec ** SSD random writes Before this change: 49.91 Mb/sec After this change: 56.39 Mb/sec ** HDD sequential writes Before this change: 68.53 Mb/sec After this change: 69.87 Mb/sec ** HDD random writes Before this change: 13.04 Mb/sec After this change: 14.39 Mb/sec Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com> Signed-off-by: Josef Bacik <jbacik@fb.com> Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28Btrfs: fix the wrong nocow range checkMiao Xie
The following warning message was outputed when running the 274th case of xfstests with nodatacow option: BUG: Bad page state in process kswapd0 pfn:1c66f page:ffffea0000636848 count:0 mapcount:0 mapping:(null) index:0x78000 page flags: 0x1000000000100a(error|uptodate|private_2) It is because the check of nocow range was wrong, we should compare the start and end position of the extent with the write position to verify if the write position was in the extent, but the current code just used the start postion to do the check, so we got the wrong extent and told the caller that it was a nocow write. And then when we write back the dirty pages, we found we should cow the extent, but at that time, there was no space in the fs, we had to the error flag for the page. When someone reclaimed that page, the above warning outputed. Fix it. Reported-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com> Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Signed-off-by: Josef Bacik <jbacik@fb.com> Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28Btrfs: reduce btree node locking duration on item updateFilipe David Borba Manana
If we do a btree search with the goal of updating an existing item without changing its size (ins_len == 0 and cow == 1), then we never need to hold locks on upper level nodes (even when slot == 0) after we COW their child nodes/leaves, as we won't have node splits or merges in this scenario (that is, no key additions, removals or shifts on any nodes or leaves). Therefore release the locks immediately after COWing the child nodes/leaves while navigating the btree, even if their parent slot is 0, instead of returning a path to the caller with those nodes locked, which would get released only when the caller releases or frees the path (or if it calls btrfs_unlock_up_safe). This is a common scenario, for example when updating inode items in fs trees and block group items in the extent tree. The following benchmarks were performed on a quad core machine with 32Gb of ram, using a leaf/node size of 4Kb (to generate deeper fs trees more quickly). sysbench --test=fileio --file-num=131072 --file-total-size=8G \ --file-test-mode=seqwr --num-threads=512 --file-block-size=8192 \ --max-requests=100000 --file-io-mode=sync [prepare|run] Before this change: 49.85Mb/s (average of 5 runs) After this change: 50.38Mb/s (average of 5 runs) Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com> Signed-off-by: Josef Bacik <jbacik@fb.com> Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28Btrfs: introduce the delayed inode ref deletion for the single link inodeMiao Xie
The inode reference item is close to inode item, so we insert it simultaneously with the inode item insertion when we create a file/directory.. In fact, we also can handle the inode reference deletion by the same way. So we made this patch to introduce the delayed inode reference deletion for the single link inode(At most case, the file doesn't has hard link, so we don't take the hard link into account). This function is based on the delayed inode mechanism. After applying this patch, we can reduce the time of the file/directory deletion by ~10%. Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28Btrfs: convert printk to btrfs_ and fix BTRFS prefixFrank Holton
Convert all applicable cases of printk and pr_* to the btrfs_* macros. Fix all uses of the BTRFS prefix. Signed-off-by: Frank Holton <fholton@gmail.com> Signed-off-by: Josef Bacik <jbacik@fb.com> Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28Btrfs: fix a warning when iput a fileWang Shilong
See the warning below: [ 1209.102076] [<ffffffffa04721b9>] remove_extent_mapping+0x69/0x70 [btrfs] [ 1209.102084] [<ffffffffa0466b06>] btrfs_evict_inode+0x96/0x4d0 [btrfs] [ 1209.102089] [<ffffffff81073010>] ? wake_atomic_t_function+0x40/0x40 [ 1209.102092] [<ffffffff8118ab2e>] evict+0x9e/0x190 [ 1209.102094] [<ffffffff8118b313>] iput+0xf3/0x180 [ 1209.102101] [<ffffffffa0461fd1>] btrfs_run_delayed_iputs+0xb1/0xd0 [btrfs] [ 1209.102107] [<ffffffffa045d358>] __btrfs_end_transaction+0x268/0x350 [btrfs] clear extent bit here to avoid triggering WARN_ON() in remove_extent_mapping() Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com> Signed-off-by: Josef Bacik <jbacik@fb.com> Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28Btrfs: remove dead comments for read_csums()Wang Shilong
Chris introduced hleper function read_csums() and this function has been removed, but we forgot to remove its corresponding comments. Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com> Signed-off-by: Josef Bacik <jbacik@fb.com> Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28Btrfs: fix error check of btrfs_lookup_dentry()Tsutomu Itoh
Clean up btrfs_lookup_dentry() to never return NULL, but PTR_ERR(-ENOENT) instead. This keeps the return value convention consistent. Callers who use btrfs_lookup_dentry() require a trivial update. create_snapshot() in particular looks like it can also lose a BUG_ON(!inode) which is not really needed - there seems less harm in returning ENOENT to userspace at that point in the stack than there is to crash the machine. Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com> Signed-off-by: Josef Bacik <jbacik@fb.com> Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28Btrfs: fix very slow inode eviction and fs unmountFilipe David Borba Manana
The inode eviction can be very slow, because during eviction we tell the VFS to truncate all of the inode's pages. This results in calls to btrfs_invalidatepage() which in turn does calls to lock_extent_bits() and clear_extent_bit(). These calls result in too many merges and splits of extent_state structures, which consume a lot of time and cpu when the inode has many pages. In some scenarios I have experienced umount times higher than 15 minutes, even when there's no pending IO (after a btrfs fs sync). A quick way to reproduce this issue: $ mkfs.btrfs -f /dev/sdb3 $ mount /dev/sdb3 /mnt/btrfs $ cd /mnt/btrfs $ sysbench --test=fileio --file-num=128 --file-total-size=16G \ --file-test-mode=seqwr --num-threads=128 \ --file-block-size=16384 --max-time=60 --max-requests=0 run $ time btrfs fi sync . FSSync '.' real 0m25.457s user 0m0.000s sys 0m0.092s $ cd .. $ time umount /mnt/btrfs real 1m38.234s user 0m0.000s sys 1m25.760s The same test on ext4 runs much faster: $ mkfs.ext4 /dev/sdb3 $ mount /dev/sdb3 /mnt/ext4 $ cd /mnt/ext4 $ sysbench --test=fileio --file-num=128 --file-total-size=16G \ --file-test-mode=seqwr --num-threads=128 \ --file-block-size=16384 --max-time=60 --max-requests=0 run $ sync $ cd .. $ time umount /mnt/ext4 real 0m3.626s user 0m0.004s sys 0m3.012s After this patch, the unmount (inode evictions) is much faster: $ mkfs.btrfs -f /dev/sdb3 $ mount /dev/sdb3 /mnt/btrfs $ cd /mnt/btrfs $ sysbench --test=fileio --file-num=128 --file-total-size=16G \ --file-test-mode=seqwr --num-threads=128 \ --file-block-size=16384 --max-time=60 --max-requests=0 run $ time btrfs fi sync . FSSync '.' real 0m26.774s user 0m0.000s sys 0m0.084s $ cd .. $ time umount /mnt/btrfs real 0m1.811s user 0m0.000s sys 0m1.564s Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com> Signed-off-by: Josef Bacik <jbacik@fb.com> Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28btrfs: expand btrfs_find_item() to include find_root_ref functionalityKelley Nielsen
This patch is the second step in bootstrapping the btrfs_find_item interface. The btrfs_find_root_ref() is similar to the former __inode_info(); it accepts four of its parameters, and duplicates the first half of its functionality. Replace the one former call to btrfs_find_root_ref() with a call to btrfs_find_item(), along with the defined key type that was used internally by btrfs_find_root ref, and a null found key. In btrfs_find_item(), add a test for the null key at the place where the functionality of btrfs_find_root_ref() ends; btrfs_find_item() then returns if the test passes. Finally, remove btrfs_find_root_ref(). Signed-off-by: Kelley Nielsen <kelleynnn@gmail.com> Suggested-by: Zach Brown <zab@redhat.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org> Signed-off-by: Josef Bacik <jbacik@fusionio.com> Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28btrfs: remove unused variable from btrfs_new_inodeValentina Giusti
Variable owner in btrfs_new_inode is unused since commit d82a6f1d7e8b61ed5996334d0db66651bb43641d (Btrfs: kill BTRFS_I(inode)->block_group) Signed-off-by: Valentina Giusti <valentina.giusti@microon.de> Signed-off-by: Josef Bacik <jbacik@fusionio.com> Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28Btrfs: incompatible format change to remove hole extentsJosef Bacik
Btrfs has always had these filler extent data items for holes in inodes. This has made somethings very easy, like logging hole punches and sending hole punches. However for large holey files these extent data items are pure overhead. So add an incompatible feature to no longer add hole extents to reduce the amount of metadata used by these sort of files. This has a few changes for logging and send obviously since they will need to detect holes and log/send the holes if there are any. I've tested this thoroughly with xfstests and it doesn't cause any issues with and without the incompat format set. Thanks, Signed-off-by: Josef Bacik <jbacik@fusionio.com> Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs updates from Al Viro: "Assorted stuff; the biggest pile here is Christoph's ACL series. Plus assorted cleanups and fixes all over the place... There will be another pile later this week" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (43 commits) __dentry_path() fixes vfs: Remove second variable named error in __dentry_path vfs: Is mounted should be testing mnt_ns for NULL or error. Fix race when checking i_size on direct i/o read hfsplus: remove can_set_xattr nfsd: use get_acl and ->set_acl fs: remove generic_acl nfs: use generic posix ACL infrastructure for v3 Posix ACLs gfs2: use generic posix ACL infrastructure jfs: use generic posix ACL infrastructure xfs: use generic posix ACL infrastructure reiserfs: use generic posix ACL infrastructure ocfs2: use generic posix ACL infrastructure jffs2: use generic posix ACL infrastructure hfsplus: use generic posix ACL infrastructure f2fs: use generic posix ACL infrastructure ext2/3/4: use generic posix ACL infrastructure btrfs: use generic posix ACL infrastructure fs: make posix_acl_create more useful fs: make posix_acl_chmod more useful ...
2014-01-25btrfs: use generic posix ACL infrastructureChristoph Hellwig
Also don't bother to set up a .get_acl method for symlinks as we do not support access control (ACLs or even mode bits) for symlinks in Linux. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-12-05fs: fix iversion handlingChristoph Hellwig
Currently notify_change directly updates i_version for size updates, which not only is counter to how all other fields are updated through struct iattr, but also breaks XFS, which need inode updates to happen under its own lock, and synchronized to the structure that gets written to the log. Remove the update in the common code, and it to btrfs and ext4, XFS already does a proper updaste internally and currently gets a double update with the existing code. IMHO this is 3.13 and -stable material and should go in through the XFS tree. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Andreas Dilger <adilger@dilger.ca> Acked-by: Jan Kara <jack@suse.cz> Reviewed-by: Dave Chinner <dchinner@redhat.com> Signed-off-by: Chris Mason <clm@fb.com> Signed-off-by: Ben Myers <bpm@sgi.com>
2013-11-23block: Abstract out bvec iteratorKent Overstreet
Immutable biovecs are going to require an explicit iterator. To implement immutable bvecs, a later patch is going to add a bi_bvec_done member to this struct; for now, this patch effectively just renames things. Signed-off-by: Kent Overstreet <kmo@daterainc.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: "Ed L. Cashin" <ecashin@coraid.com> Cc: Nick Piggin <npiggin@kernel.dk> Cc: Lars Ellenberg <drbd-dev@lists.linbit.com> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Matthew Wilcox <willy@linux.intel.com> Cc: Geoff Levand <geoff@infradead.org> Cc: Yehuda Sadeh <yehuda@inktank.com> Cc: Sage Weil <sage@inktank.com> Cc: Alex Elder <elder@inktank.com> Cc: ceph-devel@vger.kernel.org Cc: Joshua Morris <josh.h.morris@us.ibm.com> Cc: Philip Kelleher <pjk1939@linux.vnet.ibm.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Jeremy Fitzhardinge <jeremy@goop.org> Cc: Neil Brown <neilb@suse.de> Cc: Alasdair Kergon <agk@redhat.com> Cc: Mike Snitzer <snitzer@redhat.com> Cc: dm-devel@redhat.com Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: linux390@de.ibm.com Cc: Boaz Harrosh <bharrosh@panasas.com> Cc: Benny Halevy <bhalevy@tonian.com> Cc: "James E.J. Bottomley" <JBottomley@parallels.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Nicholas A. Bellinger" <nab@linux-iscsi.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Chris Mason <chris.mason@fusionio.com> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Andreas Dilger <adilger.kernel@dilger.ca> Cc: Jaegeuk Kim <jaegeuk.kim@samsung.com> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Dave Kleikamp <shaggy@kernel.org> Cc: Joern Engel <joern@logfs.org> Cc: Prasad Joshi <prasadjoshi.linux@gmail.com> Cc: Trond Myklebust <Trond.Myklebust@netapp.com> Cc: KONISHI Ryusuke <konishi.ryusuke@lab.ntt.co.jp> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Ben Myers <bpm@sgi.com> Cc: xfs@oss.sgi.com Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Len Brown <len.brown@intel.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Herton Ronaldo Krzesinski <herton.krzesinski@canonical.com> Cc: Ben Hutchings <ben@decadent.org.uk> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Guo Chao <yan@linux.vnet.ibm.com> Cc: Tejun Heo <tj@kernel.org> Cc: Asai Thambi S P <asamymuthupa@micron.com> Cc: Selvan Mani <smani@micron.com> Cc: Sam Bradshaw <sbradshaw@micron.com> Cc: Wei Yongjun <yongjun_wei@trendmicro.com.cn> Cc: "Roger Pau Monné" <roger.pau@citrix.com> Cc: Jan Beulich <jbeulich@suse.com> Cc: Stefano Stabellini <stefano.stabellini@eu.citrix.com> Cc: Ian Campbell <Ian.Campbell@citrix.com> Cc: Sebastian Ott <sebott@linux.vnet.ibm.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Jiang Liu <jiang.liu@huawei.com> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Jerome Marchand <jmarchand@redhat.com> Cc: Joe Perches <joe@perches.com> Cc: Peng Tao <tao.peng@emc.com> Cc: Andy Adamson <andros@netapp.com> Cc: fanchaoting <fanchaoting@cn.fujitsu.com> Cc: Jie Liu <jeff.liu@oracle.com> Cc: Sunil Mushran <sunil.mushran@gmail.com> Cc: "Martin K. Petersen" <martin.petersen@oracle.com> Cc: Namjae Jeon <namjae.jeon@samsung.com> Cc: Pankaj Kumar <pankaj.km@samsung.com> Cc: Dan Magenheimer <dan.magenheimer@oracle.com> Cc: Mel Gorman <mgorman@suse.de>6
2013-11-23block: Convert various code to bio_for_each_segment()Kent Overstreet
With immutable biovecs we don't want code accessing bi_io_vec directly - the uses this patch changes weren't incorrect since they all own the bio, but it makes the code harder to audit for no good reason - also, this will help with multipage bvecs later. Signed-off-by: Kent Overstreet <kmo@daterainc.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Chris Mason <chris.mason@fusionio.com> Cc: Jaegeuk Kim <jaegeuk.kim@samsung.com> Cc: Joern Engel <joern@logfs.org> Cc: Prasad Joshi <prasadjoshi.linux@gmail.com> Cc: Trond Myklebust <Trond.Myklebust@netapp.com>