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* Btrfs: fix preallocate vs double nocow writeMiao Xie2014-03-101-7/+2
| | | | | | | | | | | | | | 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>
* Btrfs: fix wrong lock range and write size in check_can_nocow()Miao Xie2014-03-101-2/+3
| | | | | | | | | | | | | | | | | | | | The write range may not be sector-aligned, for example: |--------|--------| <- write range, sector-unaligned, size: 2blocks |--------|--------|--------| <- correct lock range, size: 3blocks But according to the old code, we used the size of write range to calculate the lock range directly, not considered the offset, we would get a wrong lock range: |--------|--------| <- write range, sector-unaligned, size: 2blocks |--------|--------| <- wrong lock range, size: 2blocks And besides that, the old code also had the same problem when calculating the real write size. Correct them. Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Signed-off-by: Josef Bacik <jbacik@fb.com>
* Btrfs: more efficient btrfs_drop_extent_cacheFilipe Manana2014-03-101-5/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | While droping extent map structures from the extent cache that cover our target range, we would remove each extent map structure from the red black tree and then add either 1 or 2 new extent map structures if the former extent map covered sections outside our target range. This change simply attempts to replace the existing extent map structure with a new one that covers the subsection we're not interested in, instead of doing a red black remove operation followed by an insertion operation. The number of elements in an inode's extent map tree can get very high for large files under random writes. For example, while running the following test: sysbench --test=fileio --file-num=1 --file-total-size=10G \ --file-test-mode=rndrw --num-threads=32 --file-block-size=32768 \ --max-requests=500000 --file-rw-ratio=2 [prepare|run] I captured the following histogram capturing the number of extent_map items in the red black tree while that test was running: Count: 122462 Range: 1.000 - 172231.000; Mean: 96415.831; Median: 101855.000; Stddev: 49700.981 Percentiles: 90th: 160120.000; 95th: 166335.000; 99th: 171070.000 1.000 - 5.231: 452 | 5.231 - 187.392: 87 | 187.392 - 585.911: 206 | 585.911 - 1827.438: 623 | 1827.438 - 5695.245: 1962 # 5695.245 - 17744.861: 6204 #### 17744.861 - 55283.764: 21115 ############ 55283.764 - 172231.000: 91813 ##################################################### Benchmark: sysbench --test=fileio --file-num=1 --file-total-size=10G --file-test-mode=rndwr \ --num-threads=64 --file-block-size=32768 --max-requests=0 --max-time=60 \ --file-io-mode=sync --file-fsync-freq=0 [prepare|run] Before this change: 122.1Mb/sec After this change: 125.07Mb/sec (averages of 5 test runs) Test machine: quad core intel i5-3570K, 32Gb of ram, SSD Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com> Signed-off-by: Josef Bacik <jbacik@fb.com>
* Btrfs: don't insert useless holes when punching beyond the inode's sizeFilipe Manana2014-03-101-11/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If we punch beyond the size of an inode, we'll correctly remove any prealloc extents, but we'll also insert file extent items representing holes (disk bytenr == 0) that start with a key offset that lies beyond the inode's size and are not contiguous with the last file extent item. Example: $XFS_IO_PROG -f -c "truncate 118811" $SCRATCH_MNT/foo $XFS_IO_PROG -c "fpunch 582007 864596" $SCRATCH_MNT/foo $XFS_IO_PROG -c "pwrite -S 0x0d -b 39987 92267 39987" $SCRATCH_MNT/foo btrfs-debug-tree output: item 4 key (257 INODE_ITEM 0) itemoff 15885 itemsize 160 inode generation 6 transid 6 size 132254 block group 0 mode 100600 links 1 item 5 key (257 INODE_REF 256) itemoff 15872 itemsize 13 inode ref index 2 namelen 3 name: foo item 6 key (257 EXTENT_DATA 0) itemoff 15819 itemsize 53 extent data disk byte 0 nr 0 gen 6 extent data offset 0 nr 90112 ram 122880 extent compression 0 item 7 key (257 EXTENT_DATA 90112) itemoff 15766 itemsize 53 extent data disk byte 12845056 nr 4096 gen 6 extent data offset 0 nr 45056 ram 45056 extent compression 2 item 8 key (257 EXTENT_DATA 585728) itemoff 15713 itemsize 53 extent data disk byte 0 nr 0 gen 6 extent data offset 0 nr 860160 ram 860160 extent compression 0 The last extent item, which represents a hole, is useless as it lies beyond the inode's size. Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com> Signed-off-by: Josef Bacik <jbacik@fb.com>
* Btrfs: fix skipped error handle when log sync failedMiao Xie2014-03-101-3/+6
| | | | | | | | | | | | | | | | | It is possible that many tasks sync the log tree at the same time, but only one task can do the sync work, the others will wait for it. But those wait tasks didn't get the result of the log sync, and returned 0 when they ended the wait. It caused those tasks skipped the error handle, and the serious problem was they told the users the file sync succeeded but in fact they failed. This patch fixes this problem by introducing a log context structure, we insert it into the a global list. When the sync fails, we will set the error number of every log context in the list, then the waiting tasks get the error number of the log context and handle the error if need. Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Signed-off-by: Josef Bacik <jbacik@fb.com>
* Btrfs: faster/more efficient insertion of file extent itemsFilipe David Borba Manana2014-03-101-22/+30
| | | | | | | | | | | | | | | | | | | | | | This is an extension to my previous commit titled: "Btrfs: faster file extent item replace operations" (hash 1acae57b161ef1282f565ef907f72aeed0eb71d9) Instead of inserting the new file extent item if we deleted existing file extent items covering our target file range, also allow to insert the new file extent item if we didn't find any existing items to delete and replace_extent != 0, since in this case our caller would do another tree search to insert the new file extent item anyway, therefore just combine the two tree searches into a single one, saving cpu time, reducing lock contention and reducing btree node/leaf COW operations. This covers the case where applications keep doing tail append writes to files, which for example is the case of Apache CouchDB (its database and view index files are always open with O_APPEND). Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com> Signed-off-by: Josef Bacik <jbacik@fb.com>
* Btrfs: don't use ram_bytes for uncompressed inline itemsChris Mason2014-01-291-1/+2
| | | | | | | | | | | 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
* Btrfs: fix the race between write back and nocow buffered writeMiao Xie2014-01-281-2/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | When we ran the 274th case of xfstests with nodatacow mount option, We met the following warning message: WARNING: CPU: 1 PID: 14185 at fs/btrfs/extent-tree.c:3734 btrfs_free_reserved_data_space+0xa6/0xd0 It is caused by the race between the write back and nocow buffered write: Task1 Task2 __btrfs_buffered_write() skip data reservation reserve the metadata space copy the data dirty the pages unlock the pages write back the pages release the data space becasue there is no noreserve flag set the noreserve flag This patch fixes this problem by unlocking the pages after the noreserve flag is set. 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>
* Btrfs: make fsync latency less suckyJosef Bacik2014-01-281-0/+12
| | | | | | | | | | | | | | Looking into some performance related issues with large amounts of metadata revealed that we can have some pretty huge swings in fsync() performance. If we have a lot of delayed refs backed up (as you will tend to do with lots of metadata) fsync() will wander off and try to run some of those delayed refs which can result in reading from disk and such. Since the actual act of fsync() doesn't create any delayed refs there is no need to make it throttle on delayed ref stuff, that will be handled by other people. With this patch we get much smoother fsync performance with large amounts of metadata. Thanks, Signed-off-by: Josef Bacik <jbacik@fb.com> Signed-off-by: Chris Mason <clm@fb.com>
* Btrfs: faster file extent item replace operationsFilipe David Borba Manana2014-01-281-4/+40
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* Btrfs: fix use of uninitialized err variableFilipe David Borba Manana2014-01-281-1/+1
| | | | | | | | | fs/btrfs/file.c: In function ‘prepare_pages.isra.18’: fs/btrfs/file.c:1265:6: warning: ‘err’ may be used uninitialized in this function [-Wuninitialized] 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>
* Btrfs: fix ordered extent check in btrfs_punch_holeFilipe David Borba Manana2014-01-281-1/+1
| | | | | | | | | | | If the ordered extent's last byte was 1 less than our region's start byte, we would unnecessarily wait for the completion of that ordered extent, because it doesn't intersect our target range. 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>
* Btrfs: fix the reserved space leak caused by the race between nonlock dio ↵Miao Xie2014-01-281-47/+84
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | and buffered io When we ran sysbench on the fs with compression, the following WARN_ONs were triggered: fs/btrfs/inode.c:7829 WARN_ON(BTRFS_I(inode)->outstanding_extents); fs/btrfs/inode.c:7830 WARN_ON(BTRFS_I(inode)->reserved_extents); fs/btrfs/inode.c:7832 WARN_ON(BTRFS_I(inode)->csum_bytes); Steps to reproduce: # mkfs.btrfs -f <dev> # mount -o compress <dev> <mnt> # cd <mnt> # sysbench --test=fileio --num-threads=8 --file-total-size=8G \ > --file-block-size=32K --file-io-mode=rndwr --file-fsync-freq=0 \ > --file-fsync-end=no --max-requests=300000 --file-extra-flags=direct \ > --file-test-mode=sync prepare # cd - # umount <mnt> # mount -o compress <dev> <mnt> # cd <mnt> # sysbench --test=fileio --num-threads=8 --file-total-size=8G \ > --file-block-size=32K --file-io-mode=rndwr --file-fsync-freq=0 \ > --file-fsync-end=no --max-requests=300000 --file-extra-flags=direct \ > --file-test-mode=sync run # cd - # umount <mnt> The reason of this problem is: Task0 Task1 btrfs_direct_IO unlock(&inode->i_mutex) lock(&inode->i_mutex) reserve_space() prepare_pages() lock_extent() clear_extent() unlock_extent() lock_extent() test_extent(uptodate) return false copy_data() set_delalloc_extent() extent need compress go back to buffered write clear_extent(DELALLOC | DIRTY) unlock_extent() Task 0 and 1 wrote the same place, and task0 cleared the delalloc flag which was set by task1, it made the dirty pages in that extents couldn't be flushed into the disk, so the reserved space for that extent was not released at the end. This patch fixes the above bug by unlocking the extent after the delalloc. 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>
* Btrfs: cleanup unnecessary parameter and variant of prepare_pages()Miao Xie2014-01-281-8/+6
| | | | | | | | | | | - the caller has gotten the inode object, needn't pass the file object. And if so, we needn't define a inode pointer variant. - the position should be aligned by the page size not sector size, so we also needn't pass the root object into prepare_pages(). 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>
* Btrfs: incompatible format change to remove hole extentsJosef Bacik2014-01-281-4/+9
| | | | | | | | | | | | | | | 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>
* btrfs: Fix checkpatch.pl warning of spacing issuesDulshani Gunawardhana2013-11-111-1/+1
| | | | | | | | | Fix spacing issues detected via checkpatch.pl in accordance with the kernel style guidelines. Signed-off-by: Dulshani Gunawardhana <dulshani.gunawardhana89@gmail.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com> Signed-off-by: Chris Mason <chris.mason@fusionio.com>
* Btrfs: return an error from btrfs_wait_ordered_rangeJosef Bacik2013-11-111-27/+39
| | | | | | | | | | | I noticed that if the free space cache has an error writing out it's data it won't actually error out, it will just carry on. This is because it doesn't check the return value of btrfs_wait_ordered_range, which didn't actually return anything. So fix this in order to keep us from making free space cache look valid when it really isnt. Thanks, Signed-off-by: Josef Bacik <jbacik@fusionio.com> Signed-off-by: Chris Mason <chris.mason@fusionio.com>
* btrfs: remove fs/btrfs/compat.hZach Brown2013-11-111-1/+0
| | | | | | | | | fs/btrfs/compat.h only contained trivial macro wrappers of drop_nlink() and inc_nlink(). This doesn't belong in mainline. Signed-off-by: Zach Brown <zab@redhat.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com> Signed-off-by: Chris Mason <chris.mason@fusionio.com>
* Btrfs: fix up seek_hole/seek_data handlingJosef Bacik2013-11-111-75/+19
| | | | | | | | | | | Whoever wrote this was braindead. Also it doesn't work right if you have VACANCY's since we assumed you would only have that at the end of the file, which won't be the case in the near future. I tested this with generic/285 and generic/286 as well as the btrfs tests that use fssum since it uses seek_hole/seek_data to verify things are ok. Thanks, Signed-off-by: Josef Bacik <jbacik@fusionio.com> Signed-off-by: Chris Mason <chris.mason@fusionio.com>
* Merge branch 'for-linus' of ↵Linus Torvalds2013-09-221-2/+2
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs Pull btrfs fixes from Chris Mason: "These are mostly bug fixes and a two small performance fixes. The most important of the bunch are Josef's fix for a snapshotting regression and Mark's update to fix compile problems on arm" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (25 commits) Btrfs: create the uuid tree on remount rw btrfs: change extent-same to copy entire argument struct Btrfs: dir_inode_operations should use btrfs_update_time also btrfs: Add btrfs: prefix to kernel log output btrfs: refuse to remount read-write after abort Btrfs: btrfs_ioctl_default_subvol: Revert back to toplevel subvolume when arg is 0 Btrfs: don't leak transaction in btrfs_sync_file() Btrfs: add the missing mutex unlock in write_all_supers() Btrfs: iput inode on allocation failure Btrfs: remove space_info->reservation_progress Btrfs: kill delay_iput arg to the wait_ordered functions Btrfs: fix worst case calculator for space usage Revert "Btrfs: rework the overcommit logic to be based on the total size" Btrfs: improve replacing nocow extents Btrfs: drop dir i_size when adding new names on replay Btrfs: replay dir_index items before other items Btrfs: check roots last log commit when checking if an inode has been logged Btrfs: actually log directory we are fsync()'ing Btrfs: actually limit the size of delalloc range Btrfs: allocate the free space by the existed max extent size when ENOSPC ...
| * Btrfs: don't leak transaction in btrfs_sync_file()Filipe David Borba Manana2013-09-211-2/+2
| | | | | | | | | | | | | | | | | | In btrfs_sync_file(), if the call to btrfs_log_dentry_safe() returns a negative error (for e.g. -ENOMEM via btrfs_log_inode()), we would return without ending/freeing the transaction. Signed-off-by: Josef Bacik <jbacik@fusionio.com> Signed-off-by: Chris Mason <chris.mason@fusionio.com>
* | Merge branch 'for-linus' of ↵Linus Torvalds2013-09-121-10/+1
|\ \ | |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs Pull btrfs updates from Chris Mason: "This is against 3.11-rc7, but was pulled and tested against your tree as of yesterday. We do have two small incrementals queued up, but I wanted to get this bunch out the door before I hop on an airplane. This is a fairly large batch of fixes, performance improvements, and cleanups from the usual Btrfs suspects. We've included Stefan Behren's work to index subvolume UUIDs, which is targeted at speeding up send/receive with many subvolumes or snapshots in place. It closes a long standing performance issue that was built in to the disk format. Mark Fasheh's offline dedup work is also here. In this case offline means the FS is mounted and active, but the dedup work is not done inline during file IO. This is a building block where utilities are able to ask the FS to dedup a series of extents. The kernel takes care of verifying the data involved really is the same. Today this involves reading both extents, but we'll continue to evolve the patches" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (118 commits) Btrfs: optimize key searches in btrfs_search_slot Btrfs: don't use an async starter for most of our workers Btrfs: only update disk_i_size as we remove extents Btrfs: fix deadlock in uuid scan kthread Btrfs: stop refusing the relocation of chunk 0 Btrfs: fix memory leak of uuid_root in free_fs_info btrfs: reuse kbasename helper btrfs: return btrfs error code for dev excl ops err Btrfs: allow partial ordered extent completion Btrfs: convert all bug_ons in free-space-cache.c Btrfs: add support for asserts Btrfs: adjust the fs_devices->missing count on unmount Btrf: cleanup: don't check for root_refs == 0 twice Btrfs: fix for patch "cleanup: don't check the same thing twice" Btrfs: get rid of one BUG() in write_all_supers() Btrfs: allocate prelim_ref with a slab allocater Btrfs: pass gfp_t to __add_prelim_ref() to avoid always using GFP_ATOMIC Btrfs: fix race conditions in BTRFS_IOC_FS_INFO ioctl Btrfs: fix race between removing a dev and writing sbs Btrfs: remove ourselves from the cluster list under lock ...
| * Btrf: cleanup: don't check for root_refs == 0 twiceStefan Behrens2013-09-011-5/+0
| | | | | | | | | | | | | | | | | | | | btrfs_read_fs_root_no_name() already checks if btrfs_root_refs() is zero and returns ENOENT in this case. There is no need to do it again in three more places. Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de> Signed-off-by: Josef Bacik <jbacik@fusionio.com> Signed-off-by: Chris Mason <chris.mason@fusionio.com>
| * Btrfs: avoid starting a transaction in the write pathJosef Bacik2013-09-011-10/+1
| | | | | | | | | | | | | | | | | | | | | | | | I noticed while looking at a deadlock that we are always starting a transaction in cow_file_range(). This isn't really needed since we only need a transaction if we are doing an inline extent, or if the allocator needs to allocate a chunk. So push down all the transaction start stuff to be closer to where we actually need a transaction in all of these cases. This will hopefully reduce our write latency when we are committing often. Thanks, Signed-off-by: Josef Bacik <jbacik@fusionio.com> Signed-off-by: Chris Mason <chris.mason@fusionio.com>
| * Btrfs: don't bother autodefragging if our root is going awayJosef Bacik2013-09-011-0/+5
| | | | | | | | | | | | | | | | | | We can end up with inodes on the auto defrag list that exist on roots that are going to be deleted. This is extra work we don't need to do, so just bail if our root has 0 root refs. Thanks, Signed-off-by: Josef Bacik <jbacik@fusionio.com> Signed-off-by: Chris Mason <chris.mason@fusionio.com>
* | direct-io: Handle O_(D)SYNC AIOChristoph Hellwig2013-09-041-1/+1
|/ | | | | | | | | | | | | | Call generic_write_sync() from the deferred I/O completion handler if O_DSYNC is set for a write request. Also make sure various callers don't call generic_write_sync if the direct I/O code returns -EIOCBQUEUED. Based on an earlier patch from Jan Kara <jack@suse.cz> with updates from Jeff Moyer <jmoyer@redhat.com> and Darrick J. Wong <darrick.wong@oracle.com>. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* Btrfs: allow splitting of hole em's when dropping extent cacheJosef Bacik2013-08-091-22/+40
| | | | | | | | | | | | | | I noticed while running multi-threaded fsync tests that sometimes fsck would complain about an improper gap. This happens because we fail to add a hole extent to the file, which was happening when we'd split a hole EM because btrfs_drop_extent_cache was just discarding the whole em instead of splitting it. So this patch fixes this by allowing us to split a hole em properly, which means that added holes actually get logged properly and we no longer see this fsck error. Thankfully we're tolerant of these sort of problems so a user would not see any adverse effects of this bug, other than fsck complaining. Thanks, Signed-off-by: Josef Bacik <jbacik@fusionio.com> Signed-off-by: Chris Mason <chris.mason@fusionio.com>
* Merge branch 'for-linus' of ↵Linus Torvalds2013-07-091-21/+129
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs Pull btrfs update from Chris Mason: "These are the usual mixture of bugs, cleanups and performance fixes. Miao has some really nice tuning of our crc code as well as our transaction commits. Josef is peeling off more and more problems related to early enospc, and has a number of important bug fixes in here too" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (81 commits) Btrfs: wait ordered range before doing direct io Btrfs: only do the tree_mod_log_free_eb if this is our last ref Btrfs: hold the tree mod lock in __tree_mod_log_rewind Btrfs: make backref walking code handle skinny metadata Btrfs: fix crash regarding to ulist_add_merge Btrfs: fix several potential problems in copy_nocow_pages_for_inode Btrfs: cleanup the code of copy_nocow_pages_for_inode() Btrfs: fix oops when recovering the file data by scrub function Btrfs: make the chunk allocator completely tree lockless Btrfs: cleanup orphaned root orphan item Btrfs: fix wrong mirror number tuning Btrfs: cleanup redundant code in btrfs_submit_direct() Btrfs: remove btrfs_sector_sum structure Btrfs: check if we can nocow if we don't have data space Btrfs: stop using try_to_writeback_inodes_sb_nr to flush delalloc Btrfs: use a percpu to keep track of possibly pinned bytes Btrfs: check for actual acls rather than just xattrs when caching no acl Btrfs: move btrfs_truncate_page to btrfs_cont_expand instead of btrfs_truncate Btrfs: optimize reada_for_balance Btrfs: optimize read_block_for_search ...
| * Btrfs: check if we can nocow if we don't have data spaceJosef Bacik2013-07-021-11/+114
| | | | | | | | | | | | | | | | | | | | We always just try and reserve data space when we write, but if we are out of space but have prealloc'ed extents we should still successfully write. This patch will try and see if we can write to prealloc'ed space and if we can go ahead and allow the write to continue. With this patch we now pass xfstests generic/274. Thanks, Signed-off-by: Josef Bacik <jbacik@fusionio.com>
| * Btrfs: move btrfs_truncate_page to btrfs_cont_expand instead of btrfs_truncateJosef Bacik2013-07-011-6/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This has plagued us forever and I'm so over working around it. When we truncate down to a non-page aligned offset we will call btrfs_truncate_page to zero out the end of the page and write it back to disk, this will keep us from exposing stale data if we truncate back up from that point. The problem with this is it requires data space to do this, and people don't really expect to get ENOSPC from truncate() for these sort of things. This also tends to bite the orphan cleanup stuff too which keeps people from mounting. To get around this we can just move this into btrfs_cont_expand() to make sure if we are truncating up from a non-page size aligned i_size we will zero out the rest of this page so that we don't expose stale data. This will give ENOSPC if you try to truncate() up or if you try to write past the end of isize, which is much more reasonable. This fixes xfstests generic/083 failing to mount because of the orphan cleanup failing. Thanks, Signed-off-by: Josef Bacik <jbacik@fusionio.com>
| * Btrfs: cleanup: don't check the same thing twiceStefan Behrens2013-06-141-4/+0
| | | | | | | | | | | | | | | | | | btrfs_read_fs_root_no_name() already checks if btrfs_root_refs() is zero and returns ENOENT in this case. There is no need to do it again in six places. Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
* | vfs: export lseek_execute() to modulesJie Liu2013-07-031-14/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | For those file systems(btrfs/ext4/ocfs2/tmpfs) that support SEEK_DATA/SEEK_HOLE functions, we end up handling the similar matter in lseek_execute() to update the current file offset to the desired offset if it is valid, ceph also does the simliar things at ceph_llseek(). To reduce the duplications, this patch make lseek_execute() public accessible so that we can call it directly from the underlying file systems. Thanks Dave Chinner for this suggestion. [AV: call it vfs_setpos(), don't bring the removed 'inode' argument back] v2->v1: - Add kernel-doc comments for lseek_execute() - Call lseek_execute() in ceph->llseek() Signed-off-by: Jie Liu <jeff.liu@oracle.com> Cc: Dave Chinner <dchinner@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andi Kleen <andi@firstfloor.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Christoph Hellwig <hch@lst.de> Cc: Chris Mason <chris.mason@fusionio.com> Cc: Josef Bacik <jbacik@fusionio.com> Cc: Ben Myers <bpm@sgi.com> Cc: Ted Tso <tytso@mit.edu> Cc: Hugh Dickins <hughd@google.com> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Sage Weil <sage@inktank.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | Merge branch 'for-linus' of ↵Linus Torvalds2013-05-091-18/+19
|\ \ | |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs Pull btrfs update from Chris Mason: "These are mostly fixes. The biggest exceptions are Josef's skinny extents and Jan Schmidt's code to rebuild our quota indexes if they get out of sync (or you enable quotas on an existing filesystem). The skinny extents are off by default because they are a new variation on the extent allocation tree format. btrfstune -x enables them, and the new format makes the extent allocation tree about 30% smaller. I rebased this a few days ago to rework Dave Sterba's crc checks on the super block, but almost all of these go back to rc6, since I though 3.9 was due any minute. The biggest missing fix is the tracepoint bug that was hit late in 3.9. I ran into problems with that in overnight testing and I'm still tracking it down. I'll definitely have that fixed for rc2." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (101 commits) Btrfs: allow superblock mismatch from older mkfs btrfs: enhance superblock checks btrfs: fix misleading variable name for flags btrfs: use unsigned long type for extent state bits Btrfs: improve the loop of scrub_stripe btrfs: read entire device info under lock btrfs: remove unused gfp mask parameter from release_extent_buffer callchain btrfs: handle errors returned from get_tree_block_key btrfs: make static code static & remove dead code Btrfs: deal with errors in write_dev_supers Btrfs: remove almost all of the BUG()'s from tree-log.c Btrfs: deal with free space cache errors while replaying log Btrfs: automatic rescan after "quota enable" command Btrfs: rescan for qgroups Btrfs: split btrfs_qgroup_account_ref into four functions Btrfs: allocate new chunks if the space is not enough for global rsv Btrfs: separate sequence numbers for delayed ref tracking and tree mod log btrfs: move leak debug code to functions Btrfs: return free space in cow error path Btrfs: set UUID in root_item for created trees ...
| * btrfs: make static code static & remove dead codeEric Sandeen2013-05-061-6/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Big patch, but all it does is add statics to functions which are in fact static, then remove the associated dead-code fallout. removed functions: btrfs_iref_to_path() __btrfs_lookup_delayed_deletion_item() __btrfs_search_delayed_insertion_item() __btrfs_search_delayed_deletion_item() find_eb_for_page() btrfs_find_block_group() range_straddles_pages() extent_range_uptodate() btrfs_file_extent_length() btrfs_scrub_cancel_devid() btrfs_start_transaction_lflush() btrfs_print_tree() is left because it is used for debugging. btrfs_start_transaction_lflush() and btrfs_reada_detach() are left for symmetry. ulist.c functions are left, another patch will take care of those. Signed-off-by: Eric Sandeen <sandeen@redhat.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
| * Btrfs: cleanup of function where fixup_low_keys() is calledTsutomu Itoh2013-05-061-4/+4
| | | | | | | | | | | | | | | | If argument 'trans' is unnecessary in the function where fixup_low_keys() is called, 'trans' is deleted. Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
| * Btrfs: fix bad extent loggingJosef Bacik2013-05-061-8/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A user sent me a btrfs-image of a file system that was panicing on mount during the log recovery. I had originally thought these problems were from a bug in the free space cache code, but that was just a symptom of the problem. The problem is if your application does something like this [prealloc][prealloc][prealloc] the internal extent maps will merge those all together into one extent map, even though on disk they are 3 separate extents. So if you go to write into one of these ranges the extent map will be right since we use the physical extent when doing the write, but when we log the extents they will use the wrong sizes for the remainder prealloc space. If this doesn't happen to trip up the free space cache (which it won't in a lot of cases) then you will get bogus entries in your extent tree which will screw stuff up later. The data and such will still work, but everything else is broken. This patch fixes this by not allowing extents that are on the modified list to be merged. This has the side effect that we are no longer adding everything to the modified list all the time, which means we now have to call btrfs_drop_extents every time we log an extent into the tree. So this allows me to drop all this speciality code I was using to get around calling btrfs_drop_extents. With this patch the testcase I've created no longer creates a bogus file system after replaying the log. Thanks, Signed-off-by: Josef Bacik <jbacik@fusionio.com>
| * Btrfs: log ram bytes properlyJosef Bacik2013-05-061-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | When logging changed extents I was logging ram_bytes as the current length, which isn't correct, it's supposed to be the ram bytes of the original extent. This is for compression where even if we split the extent we need to know the ram bytes so when we uncompress the extent we know how big it will be. This was still working out right with compression for some reason but I think we were getting lucky. It was definitely off for prealloc which is why I noticed it, btrfsck was complaining about it. With this patch btrfsck no longer complains after a log replay. Thanks, Signed-off-by: Josef Bacik <jbacik@fusionio.com>
* | aio: don't include aio.h in sched.hKent Overstreet2013-05-071-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Faster kernel compiles by way of fewer unnecessary includes. [akpm@linux-foundation.org: fix fallout] [akpm@linux-foundation.org: fix build] Signed-off-by: Kent Overstreet <koverstreet@google.com> Cc: Zach Brown <zab@redhat.com> Cc: Felipe Balbi <balbi@ti.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Jens Axboe <axboe@kernel.dk> Cc: Asai Thambi S P <asamymuthupa@micron.com> Cc: Selvan Mani <smani@micron.com> Cc: Sam Bradshaw <sbradshaw@micron.com> Cc: Jeff Moyer <jmoyer@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Benjamin LaHaise <bcrl@kvack.org> Reviewed-by: "Theodore Ts'o" <tytso@mit.edu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | Merge branch 'for-linus' of ↵Linus Torvalds2013-05-011-3/+0
|\ \ | |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull VFS updates from Al Viro, Misc cleanups all over the place, mainly wrt /proc interfaces (switch create_proc_entry to proc_create(), get rid of the deprecated create_proc_read_entry() in favor of using proc_create_data() and seq_file etc). 7kloc removed. * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (204 commits) don't bother with deferred freeing of fdtables proc: Move non-public stuff from linux/proc_fs.h to fs/proc/internal.h proc: Make the PROC_I() and PDE() macros internal to procfs proc: Supply a function to remove a proc entry by PDE take cgroup_open() and cpuset_open() to fs/proc/base.c ppc: Clean up scanlog ppc: Clean up rtas_flash driver somewhat hostap: proc: Use remove_proc_subtree() drm: proc: Use remove_proc_subtree() drm: proc: Use minor->index to label things, not PDE->name drm: Constify drm_proc_list[] zoran: Don't print proc_dir_entry data in debug reiserfs: Don't access the proc_dir_entry in r_open(), r_start() r_show() proc: Supply an accessor for getting the data from a PDE's parent airo: Use remove_proc_subtree() rtl8192u: Don't need to save device proc dir PDE rtl8187se: Use a dir under /proc/net/r8180/ proc: Add proc_mkdir_data() proc: Move some bits from linux/proc_fs.h to linux/{of.h,signal.h,tty.h} proc: Move PDE_NET() to fs/proc/proc_net.c ...
| * lift sb_start_write/sb_end_write out of ->aio_write()Al Viro2013-04-091-3/+0
| | | | | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | Merge branch 'for-linus' of ↵Linus Torvalds2013-03-291-0/+9
|\ \ | |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs Pull btrfs fixes from Chris Mason: "We've had a busy two weeks of bug fixing. The biggest patches in here are some long standing early-enospc problems (Josef) and a very old race where compression and mmap combine forces to lose writes (me). I'm fairly sure the mmap bug goes all the way back to the introduction of the compression code, which is proof that fsx doesn't trigger every possible mmap corner after all. I'm sure you'll notice one of these is from this morning, it's a small and isolated use-after-free fix in our scrub error reporting. I double checked it here." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: Btrfs: don't drop path when printing out tree errors in scrub Btrfs: fix wrong return value of btrfs_lookup_csum() Btrfs: fix wrong reservation of csums Btrfs: fix double free in the btrfs_qgroup_account_ref() Btrfs: limit the global reserve to 512mb Btrfs: hold the ordered operations mutex when waiting on ordered extents Btrfs: fix space accounting for unlink and rename Btrfs: fix space leak when we fail to reserve metadata space Btrfs: fix EIO from btrfs send in is_extent_unchanged for punched holes Btrfs: fix race between mmap writes and compression Btrfs: fix memory leak in btrfs_create_tree() Btrfs: fix locking on ROOT_REPLACE operations in tree mod log Btrfs: fix missing qgroup reservation before fallocating Btrfs: handle a bogus chunk tree nicely Btrfs: update to use fs_state bit
| * Btrfs: fix missing qgroup reservation before fallocatingWang Shilong2013-03-211-0/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Steps to reproduce: mkfs.btrfs <disk> mount <disk> <mnt> btrfs quota enable <mnt> btrfs sub create <mnt>/subv btrfs qgroup limit 10M <mnt>/subv fallocate --length 20M <mnt>/subv/data For the above example, fallocating will return successfully which is not expected, we try to fix it by doing qgroup reservation before fallocating. Signed-off-by: Wang Shilong <wangsl-fnst@cn.fujitsu.com> Reviewed-by: Miao Xie <miaox@cn.fujitsu.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com> Signed-off-by: Chris Mason <chris.mason@fusionio.com>
* | Merge branch 'for-linus' of ↵Linus Torvalds2013-03-171-0/+1
|\ \ | |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs Pull btrfs fixes from Chris Mason: "Eric's rcu barrier patch fixes a long standing problem with our unmount code hanging on to devices in workqueue helpers. Liu Bo nailed down a difficult assertion for in-memory extent mappings." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: Btrfs: fix warning of free_extent_map Btrfs: fix warning when creating snapshots Btrfs: return as soon as possible when edquot happens Btrfs: return EIO if we have extent tree corruption btrfs: use rcu_barrier() to wait for bdev puts at unmount Btrfs: remove btrfs_try_spin_lock Btrfs: get better concurrency for snapshot-aware defrag work
| * Btrfs: fix warning of free_extent_mapLiu Bo2013-03-151-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Users report that an extent map's list is still linked when it's actually going to be freed from cache. The story is that a) when we're going to drop an extent map and may split this large one into smaller ems, and if this large one is flagged as EXTENT_FLAG_LOGGING which means that it's on the list to be logged, then the smaller ems split from it will also be flagged as EXTENT_FLAG_LOGGING, and this is _not_ expected. b) we'll keep ems from unlinking the list and freeing when they are flagged with EXTENT_FLAG_LOGGING, because the log code holds one reference. The end result is the warning, but the truth is that we set the flag EXTENT_FLAG_LOGGING only during fsync. So clear flag EXTENT_FLAG_LOGGING for extent maps split from a large one. Reported-by: Johannes Hirte <johannes.hirte@fem.tu-ilmenau.de> Reported-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: Chris Mason <chris.mason@fusionio.com>
* | Merge branch 'for-linus' of ↵Linus Torvalds2013-03-021-10/+47
|\ \ | |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs Pull btrfs update from Chris Mason: "The biggest feature in the pull is the new (and still experimental) raid56 code that David Woodhouse started long ago. I'm still working on the parity logging setup that will avoid inconsistent parity after a crash, so this is only for testing right now. But, I'd really like to get it out to a broader audience to hammer out any performance issues or other problems. scrub does not yet correct errors on raid5/6 either. Josef has another pass at fsync performance. The big change here is to combine waiting for metadata with waiting for data, which is a big latency win. It is also step one toward using atomics from the hardware during a commit. Mark Fasheh has a new way to use btrfs send/receive to send only the metadata changes. SUSE is using this to make snapper more efficient at finding changes between snapshosts. Snapshot-aware defrag is also included. Otherwise we have a large number of fixes and cleanups. Eric Sandeen wins the award for removing the most lines, and I'm hoping we steal this idea from XFS over and over again." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (118 commits) btrfs: fixup/remove module.h usage as required Btrfs: delete inline extents when we find them during logging btrfs: try harder to allocate raid56 stripe cache Btrfs: cleanup to make the function btrfs_delalloc_reserve_metadata more logic Btrfs: don't call btrfs_qgroup_free if just btrfs_qgroup_reserve fails Btrfs: remove reduplicate check about root in the function btrfs_clean_quota_tree Btrfs: return ENOMEM rather than use BUG_ON when btrfs_alloc_path fails Btrfs: fix missing deleted items in btrfs_clean_quota_tree btrfs: use only inline_pages from extent buffer Btrfs: fix wrong reserved space when deleting a snapshot/subvolume Btrfs: fix wrong reserved space in qgroup during snap/subv creation Btrfs: remove unnecessary dget_parent/dput when creating the pending snapshot btrfs: remove a printk from scan_one_device Btrfs: fix NULL pointer after aborting a transaction Btrfs: fix memory leak of log roots Btrfs: copy everything if we've created an inline extent btrfs: cleanup for open-coded alignment Btrfs: do not change inode flags in rename Btrfs: use reserved space for creating a snapshot clear chunk_alloc flag on retryable failure ...
| * btrfs: cleanup for open-coded alignmentQu Wenruo2013-02-261-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Though most of the btrfs codes are using ALIGN macro for page alignment, there are still some codes using open-coded alignment like the following: ------ u64 mask = ((u64)root->stripesize - 1); u64 ret = (val + mask) & ~mask; ------ Or even hidden one: ------ num_bytes = (end - start + blocksize) & ~(blocksize - 1); ------ Sometimes these open-coded alignment is not so easy to understand for newbie like me. This commit changes the open-coded alignment to the ALIGN macro for a better readability. Also there is a previous patch from David Sterba with similar changes, but the patch is for 3.2 kernel and seems not merged. http://www.spinics.net/lists/linux-btrfs/msg12747.html Cc: David Sterba <dave@jikos.cz> Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
| * Btrfs: fix remount vs autodefragMiao Xie2013-02-211-0/+5
| | | | | | | | | | | | | | | | If we remount the fs to close the auto defragment or make the fs R/O, we should stop the auto defragment. Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Signed-off-by: Chris Mason <chris.mason@fusionio.com>
| * Merge branch 'master' of ↵Chris Mason2013-02-201-8/+41
| |\ | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/josef/btrfs-next into for-linus-3.9 Signed-off-by: Chris Mason <chris.mason@fusionio.com> Conflicts: fs/btrfs/disk-io.c
| | * Btrfs: place ordered operations on a per transaction listJosef Bacik2013-02-201-1/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Miao made the ordered operations stuff run async, which introduced a deadlock where we could get somebody (sync) racing in and committing the transaction while a commit was already happening. The new committer would try and flush ordered operations which would hang waiting for the commit to finish because it is done asynchronously and no longer inherits the callers trans handle. To fix this we need to make the ordered operations list a per transaction list. We can get new inodes added to the ordered operation list by truncating them and then having another process writing to them, so this makes it so that anybody trying to add an ordered operation _must_ start a transaction in order to add itself to the list, which will keep new inodes from getting added to the ordered operations list after we start committing. This should fix the deadlock and also keeps us from doing a lot more work than we need to during commit. Thanks, Signed-off-by: Josef Bacik <jbacik@fusionio.com>
| | * Btrfs: use bit operation for ->fs_stateMiao Xie2013-02-201-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There is no lock to protect fs_info->fs_state, it will introduce some problems, such as the value may be covered by the other task when several tasks modify it. For example: Task0 - CPU0 Task1 - CPU1 mov %fs_state rax or $0x1 rax mov %fs_state rax or $0x2 rax mov rax %fs_state mov rax %fs_state The expected value is 3, but in fact, it is 2. Though this problem doesn't happen now (because there is only one flag currently), the code is error prone, if we add other flags, the above problem will happen to a certainty. Now we use bit operation for it to fix the above problem. In this way, we can make the code more robust and be easy to add new flags. Signed-off-by: Miao Xie <miaox@cn.fujitsu.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
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