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2016-10-26Btrfs: fix race leading to BUG_ON when running delalloc for nodatacowFilipe Manana1-2/+8
commit 1d512cb77bdbda80f0dd0620a3b260d697fd581d upstream. If we are using the NO_HOLES feature, we have a tiny time window when running delalloc for a nodatacow inode where we can race with a concurrent link or xattr add operation leading to a BUG_ON. This happens because at run_delalloc_nocow() we end up casting a leaf item of type BTRFS_INODE_[REF|EXTREF]_KEY or of type BTRFS_XATTR_ITEM_KEY to a file extent item (struct btrfs_file_extent_item) and then analyse its extent type field, which won't match any of the expected extent types (values BTRFS_FILE_EXTENT_[REG|PREALLOC|INLINE]) and therefore trigger an explicit BUG_ON(1). The following sequence diagram shows how the race happens when running a no-cow dellaloc range [4K, 8K[ for inode 257 and we have the following neighbour leafs: Leaf X (has N items) Leaf Y [ ... (257 INODE_ITEM 0) (257 INODE_REF 256) ] [ (257 EXTENT_DATA 8192), ... ] slot N - 2 slot N - 1 slot 0 (Note the implicit hole for inode 257 regarding the [0, 8K[ range) CPU 1 CPU 2 run_dealloc_nocow() btrfs_lookup_file_extent() --> searches for a key with value (257 EXTENT_DATA 4096) in the fs/subvol tree --> returns us a path with path->nodes[0] == leaf X and path->slots[0] == N because path->slots[0] is >= btrfs_header_nritems(leaf X), it calls btrfs_next_leaf() btrfs_next_leaf() --> releases the path hard link added to our inode, with key (257 INODE_REF 500) added to the end of leaf X, so leaf X now has N + 1 keys --> searches for the key (257 INODE_REF 256), because it was the last key in leaf X before it released the path, with path->keep_locks set to 1 --> ends up at leaf X again and it verifies that the key (257 INODE_REF 256) is no longer the last key in the leaf, so it returns with path->nodes[0] == leaf X and path->slots[0] == N, pointing to the new item with key (257 INODE_REF 500) the loop iteration of run_dealloc_nocow() does not break out the loop and continues because the key referenced in the path at path->nodes[0] and path->slots[0] is for inode 257, its type is < BTRFS_EXTENT_DATA_KEY and its offset (500) is less then our delalloc range's end (8192) the item pointed by the path, an inode reference item, is (incorrectly) interpreted as a file extent item and we get an invalid extent type, leading to the BUG_ON(1): if (extent_type == BTRFS_FILE_EXTENT_REG || extent_type == BTRFS_FILE_EXTENT_PREALLOC) { (...) } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) { (...) } else { BUG_ON(1) } The same can happen if a xattr is added concurrently and ends up having a key with an offset smaller then the delalloc's range end. So fix this by skipping keys with a type smaller than BTRFS_EXTENT_DATA_KEY. Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Zefan Li <lizefan@huawei.com>
2016-04-27btrfs: skip waiting on ordered range for special filesJeff Mahoney1-1/+2
commit a30e577c96f59b1e1678ea5462432b09bf7d5cbc upstream. In btrfs_evict_inode, we properly truncate the page cache for evicted inodes but then we call btrfs_wait_ordered_range for every inode as well. It's the right thing to do for regular files but results in incorrect behavior for device inodes for block devices. filemap_fdatawrite_range gets called with inode->i_mapping which gets resolved to the block device inode before getting passed to wbc_attach_fdatawrite_inode and ultimately to inode_to_bdi. What happens next depends on whether there's an open file handle associated with the inode. If there is, we write to the block device, which is unexpected behavior. If there isn't, we through normally and inode->i_data is used. We can also end up racing against open/close which can result in crashes when i_mapping points to a block device inode that has been closed. Since there can't be any page cache associated with special file inodes, it's safe to skip the btrfs_wait_ordered_range call entirely and avoid the problem. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=100911 Tested-by: Christoph Biedl <linux-kernel.bfrz@manchmal.in-ulm.de> Signed-off-by: Jeff Mahoney <jeffm@suse.com> Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Zefan Li <lizefan@huawei.com>
2016-03-21Btrfs: use kmem_cache_free when freeing entry in inode cacheFilipe Manana1-1/+1
commit c3f4a1685bb87e59c886ee68f7967eae07d4dffa upstream. The free space entries are allocated using kmem_cache_zalloc(), through __btrfs_add_free_space(), therefore we should use kmem_cache_free() and not kfree() to avoid any confusion and any potential problem. Looking at the kfree() definition at mm/slab.c it has the following comment: /* * (...) * * Don't free memory not originally allocated by kmalloc() * or you will run into trouble. */ So better be safe and use kmem_cache_free(). Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.cz> Signed-off-by: Chris Mason <clm@fb.com> Signed-off-by: Zefan Li <lizefan@huawei.com>
2015-09-18Btrfs: fix inode eviction infinite loop after cloning into itFilipe Manana1-0/+5
commit ccccf3d67294714af2d72a6fd6fd7d73b01c9329 upstream. If we attempt to clone a 0 length region into a file we can end up inserting a range in the inode's extent_io tree with a start offset that is greater then the end offset, which triggers immediately the following warning: [ 3914.619057] WARNING: CPU: 17 PID: 4199 at fs/btrfs/extent_io.c:435 insert_state+0x4b/0x10b [btrfs]() [ 3914.620886] BTRFS: end < start 4095 4096 (...) [ 3914.638093] Call Trace: [ 3914.638636] [<ffffffff81425fd9>] dump_stack+0x4c/0x65 [ 3914.639620] [<ffffffff81045390>] warn_slowpath_common+0xa1/0xbb [ 3914.640789] [<ffffffffa03ca44f>] ? insert_state+0x4b/0x10b [btrfs] [ 3914.642041] [<ffffffff810453f0>] warn_slowpath_fmt+0x46/0x48 [ 3914.643236] [<ffffffffa03ca44f>] insert_state+0x4b/0x10b [btrfs] [ 3914.644441] [<ffffffffa03ca729>] __set_extent_bit+0x107/0x3f4 [btrfs] [ 3914.645711] [<ffffffffa03cb256>] lock_extent_bits+0x65/0x1bf [btrfs] [ 3914.646914] [<ffffffff8142b2fb>] ? _raw_spin_unlock+0x28/0x33 [ 3914.648058] [<ffffffffa03cbac4>] ? test_range_bit+0xcc/0xde [btrfs] [ 3914.650105] [<ffffffffa03cb3c3>] lock_extent+0x13/0x15 [btrfs] [ 3914.651361] [<ffffffffa03db39e>] lock_extent_range+0x3d/0xcd [btrfs] [ 3914.652761] [<ffffffffa03de1fe>] btrfs_ioctl_clone+0x278/0x388 [btrfs] [ 3914.654128] [<ffffffff811226dd>] ? might_fault+0x58/0xb5 [ 3914.655320] [<ffffffffa03e0909>] btrfs_ioctl+0xb51/0x2195 [btrfs] (...) [ 3914.669271] ---[ end trace 14843d3e2e622fc1 ]--- This later makes the inode eviction handler enter an infinite loop that keeps dumping the following warning over and over: [ 3915.117629] WARNING: CPU: 22 PID: 4228 at fs/btrfs/extent_io.c:435 insert_state+0x4b/0x10b [btrfs]() [ 3915.119913] BTRFS: end < start 4095 4096 (...) [ 3915.137394] Call Trace: [ 3915.137913] [<ffffffff81425fd9>] dump_stack+0x4c/0x65 [ 3915.139154] [<ffffffff81045390>] warn_slowpath_common+0xa1/0xbb [ 3915.140316] [<ffffffffa03ca44f>] ? insert_state+0x4b/0x10b [btrfs] [ 3915.141505] [<ffffffff810453f0>] warn_slowpath_fmt+0x46/0x48 [ 3915.142709] [<ffffffffa03ca44f>] insert_state+0x4b/0x10b [btrfs] [ 3915.143849] [<ffffffffa03ca729>] __set_extent_bit+0x107/0x3f4 [btrfs] [ 3915.145120] [<ffffffffa038c1e3>] ? btrfs_kill_super+0x17/0x23 [btrfs] [ 3915.146352] [<ffffffff811548f6>] ? deactivate_locked_super+0x3b/0x50 [ 3915.147565] [<ffffffffa03cb256>] lock_extent_bits+0x65/0x1bf [btrfs] [ 3915.148785] [<ffffffff8142b7e2>] ? _raw_write_unlock+0x28/0x33 [ 3915.149931] [<ffffffffa03bc325>] btrfs_evict_inode+0x196/0x482 [btrfs] [ 3915.151154] [<ffffffff81168904>] evict+0xa0/0x148 [ 3915.152094] [<ffffffff811689e5>] dispose_list+0x39/0x43 [ 3915.153081] [<ffffffff81169564>] evict_inodes+0xdc/0xeb [ 3915.154062] [<ffffffff81154418>] generic_shutdown_super+0x49/0xef [ 3915.155193] [<ffffffff811546d1>] kill_anon_super+0x13/0x1e [ 3915.156274] [<ffffffffa038c1e3>] btrfs_kill_super+0x17/0x23 [btrfs] (...) [ 3915.167404] ---[ end trace 14843d3e2e622fc2 ]--- So just bail out of the clone ioctl if the length of the region to clone is zero, without locking any extent range, in order to prevent this issue (same behaviour as a pwrite with a 0 length for example). This is trivial to reproduce. For example, the steps for the test I just made for fstests: mkfs.btrfs -f SCRATCH_DEV mount SCRATCH_DEV $SCRATCH_MNT touch $SCRATCH_MNT/foo touch $SCRATCH_MNT/bar $CLONER_PROG -s 0 -d 4096 -l 0 $SCRATCH_MNT/foo $SCRATCH_MNT/bar umount $SCRATCH_MNT A test case for fstests follows soon. Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: Omar Sandoval <osandov@osandov.com> Signed-off-by: Chris Mason <clm@fb.com> Signed-off-by: Zefan Li <lizefan@huawei.com>
2015-09-18btrfs: don't accept bare namespace as a valid xattrDavid Sterba1-13/+37
commit 3c3b04d10ff1811a27f86684ccd2f5ba6983211d upstream. Due to insufficient check in btrfs_is_valid_xattr, this unexpectedly works: $ touch file $ setfattr -n user. -v 1 file $ getfattr -d file user.="1" ie. the missing attribute name after the namespace. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=94291 Reported-by: William Douglas <william.douglas@intel.com> Signed-off-by: David Sterba <dsterba@suse.cz> Signed-off-by: Chris Mason <clm@fb.com> [lizf: Backported to 3.4: - 3.4 doesn't support XATTR_BTRFS_PREFIX] Signed-off-by: Zefan Li <lizefan@huawei.com>
2015-09-18Btrfs: fix log tree corruption when fs mounted with -o discardFilipe Manana1-3/+2
commit dcc82f4783ad91d4ab654f89f37ae9291cdc846a upstream. While committing a transaction we free the log roots before we write the new super block. Freeing the log roots implies marking the disk location of every node/leaf (metadata extent) as pinned before the new super block is written. This is to prevent the disk location of log metadata extents from being reused before the new super block is written, otherwise we would have a corrupted log tree if before the new super block is written a crash/reboot happens and the location of any log tree metadata extent ended up being reused and rewritten. Even though we pinned the log tree's metadata extents, we were issuing a discard against them if the fs was mounted with the -o discard option, resulting in corruption of the log tree if a crash/reboot happened before writing the new super block - the next time the fs was mounted, during the log replay process we would find nodes/leafs of the log btree with a content full of zeroes, causing the process to fail and require the use of the tool btrfs-zero-log to wipeout the log tree (and all data previously fsynced becoming lost forever). Fix this by not doing a discard when pinning an extent. The discard will be done later when it's safe (after the new super block is committed) at extent-tree.c:btrfs_finish_extent_commit(). Fixes: e688b7252f78 (Btrfs: fix extent pinning bugs in the tree log) Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Chris Mason <clm@fb.com> Signed-off-by: Zefan Li <lizefan@huawei.com>
2015-04-14Btrfs: fix fs corruption on transaction abort if device supports discardFilipe Manana2-10/+6
commit 678886bdc6378c1cbd5072da2c5a3035000214e3 upstream. When we abort a transaction we iterate over all the ranges marked as dirty in fs_info->freed_extents[0] and fs_info->freed_extents[1], clear them from those trees, add them back (unpin) to the free space caches and, if the fs was mounted with "-o discard", perform a discard on those regions. Also, after adding the regions to the free space caches, a fitrim ioctl call can see those ranges in a block group's free space cache and perform a discard on the ranges, so the same issue can happen without "-o discard" as well. This causes corruption, affecting one or multiple btree nodes (in the worst case leaving the fs unmountable) because some of those ranges (the ones in the fs_info->pinned_extents tree) correspond to btree nodes/leafs that are referred by the last committed super block - breaking the rule that anything that was committed by a transaction is untouched until the next transaction commits successfully. I ran into this while running in a loop (for several hours) the fstest that I recently submitted: [PATCH] fstests: add btrfs test to stress chunk allocation/removal and fstrim The corruption always happened when a transaction aborted and then fsck complained like this: _check_btrfs_filesystem: filesystem on /dev/sdc is inconsistent *** fsck.btrfs output *** Check tree block failed, want=94945280, have=0 Check tree block failed, want=94945280, have=0 Check tree block failed, want=94945280, have=0 Check tree block failed, want=94945280, have=0 Check tree block failed, want=94945280, have=0 read block failed check_tree_block Couldn't open file system In this case 94945280 corresponded to the root of a tree. Using frace what I observed was the following sequence of steps happened: 1) transaction N started, fs_info->pinned_extents pointed to fs_info->freed_extents[0]; 2) node/eb 94945280 is created; 3) eb is persisted to disk; 4) transaction N commit starts, fs_info->pinned_extents now points to fs_info->freed_extents[1], and transaction N completes; 5) transaction N + 1 starts; 6) eb is COWed, and btrfs_free_tree_block() called for this eb; 7) eb range (94945280 to 94945280 + 16Kb) is added to fs_info->pinned_extents (fs_info->freed_extents[1]); 8) Something goes wrong in transaction N + 1, like hitting ENOSPC for example, and the transaction is aborted, turning the fs into readonly mode. The stack trace I got for example: [112065.253935] [<ffffffff8140c7b6>] dump_stack+0x4d/0x66 [112065.254271] [<ffffffff81042984>] warn_slowpath_common+0x7f/0x98 [112065.254567] [<ffffffffa0325990>] ? __btrfs_abort_transaction+0x50/0x10b [btrfs] [112065.261674] [<ffffffff810429e5>] warn_slowpath_fmt+0x48/0x50 [112065.261922] [<ffffffffa032949e>] ? btrfs_free_path+0x26/0x29 [btrfs] [112065.262211] [<ffffffffa0325990>] __btrfs_abort_transaction+0x50/0x10b [btrfs] [112065.262545] [<ffffffffa036b1d6>] btrfs_remove_chunk+0x537/0x58b [btrfs] [112065.262771] [<ffffffffa033840f>] btrfs_delete_unused_bgs+0x1de/0x21b [btrfs] [112065.263105] [<ffffffffa0343106>] cleaner_kthread+0x100/0x12f [btrfs] (...) [112065.264493] ---[ end trace dd7903a975a31a08 ]--- [112065.264673] BTRFS: error (device sdc) in btrfs_remove_chunk:2625: errno=-28 No space left [112065.264997] BTRFS info (device sdc): forced readonly 9) The clear kthread sees that the BTRFS_FS_STATE_ERROR bit is set in fs_info->fs_state and calls btrfs_cleanup_transaction(), which in turn calls btrfs_destroy_pinned_extent(); 10) Then btrfs_destroy_pinned_extent() iterates over all the ranges marked as dirty in fs_info->freed_extents[], and for each one it calls discard, if the fs was mounted with "-o discard", and adds the range to the free space cache of the respective block group; 11) btrfs_trim_block_group(), invoked from the fitrim ioctl code path, sees the free space entries and performs a discard; 12) After an umount and mount (or fsck), our eb's location on disk was full of zeroes, and it should have been untouched, because it was marked as dirty in the fs_info->pinned_extents tree, and therefore used by the trees that the last committed superblock points to. Fix this by not performing a discard and not adding the ranges to the free space caches - it's useless from this point since the fs is now in readonly mode and we won't write free space caches to disk anymore (otherwise we would leak space) nor any new superblock. By not adding the ranges to the free space caches, it prevents other code paths from allocating that space and write to it as well, therefore being safer and simpler. This isn't a new problem, as it's been present since 2011 (git commit acce952b0263825da32cf10489413dec78053347). Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Chris Mason <clm@fb.com> Signed-off-by: Zefan Li <lizefan@huawei.com>
2015-02-02Btrfs: fix kfree on list_head in btrfs_lookup_csums_range error cleanupChris Mason1-1/+1
commit 6e5aafb27419f32575b27ef9d6a31e5d54661aca upstream. If we hit any errors in btrfs_lookup_csums_range, we'll loop through all the csums we allocate and free them. But the code was using list_entry incorrectly, and ended up trying to free the on-stack list_head instead. This bug came from commit 0678b6185 btrfs: Don't BUG_ON kzalloc error in btrfs_lookup_csums_range() Signed-off-by: Chris Mason <clm@fb.com> Reported-by: Erik Berg <btrfs@slipsprogrammoer.no> Signed-off-by: Zefan Li <lizefan@huawei.com>
2014-07-01btrfs: fix use of uninit "ret" in end_extent_writepage()Eric Sandeen1-1/+1
commit 3e2426bd0eb980648449e7a2f5a23e3cd3c7725c upstream. If this condition in end_extent_writepage() is false: if (tree->ops && tree->ops->writepage_end_io_hook) we will then test an uninitialized "ret" at: ret = ret < 0 ? ret : -EIO; The test for ret is for the case where ->writepage_end_io_hook failed, and we'd choose that ret as the error; but if there is no ->writepage_end_io_hook, nothing sets ret. Initializing ret to 0 should be sufficient; if writepage_end_io_hook wasn't set, (!uptodate) means non-zero err was passed in, so we choose -EIO in that case. Signed-of-by: Eric Sandeen <sandeen@redhat.com> Signed-off-by: Chris Mason <clm@fb.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-07-01Btrfs: use right type to get real comparisonLiu Bo1-1/+1
commit cd857dd6bc2ae9ecea14e75a34e8a8fdc158e307 upstream. We want to make sure the point is still within the extent item, not to verify the memory it's pointing to. Signed-off-by: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: Chris Mason <clm@fb.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-07-01fs: btrfs: volumes.c: Fix for possible null pointer dereferenceRickard Strandqvist1-2/+3
commit 8321cf2596d283821acc466377c2b85bcd3422b7 upstream. There is otherwise a risk of a possible null pointer dereference. Was largely found by using a static code analysis program called cppcheck. Signed-off-by: Rickard Strandqvist <rickard_strandqvist@spectrumdigital.se> Signed-off-by: Chris Mason <clm@fb.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-07-01Btrfs: fix double free in find_lock_delalloc_rangeChris Mason1-0/+1
commit 7d78874273463a784759916fc3e0b4e2eb141c70 upstream. We need to NULL the cached_state after freeing it, otherwise we might free it again if find_delalloc_range doesn't find anything. Signed-off-by: Chris Mason <clm@fb.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-03-24Btrfs: fix data corruption when reading/updating compressed extentsFilipe David Borba Manana1-0/+2
commit a2aa75e18a21b21952dc6daa9bac7c9f4426f81f upstream. When using a mix of compressed file extents and prealloc extents, it is possible to fill a page of a file with random, garbage data from some unrelated previous use of the page, instead of a sequence of zeroes. A simple sequence of steps to get into such case, taken from the test case I made for xfstests, is: _scratch_mkfs _scratch_mount "-o compress-force=lzo" $XFS_IO_PROG -f -c "pwrite -S 0x06 -b 18670 266978 18670" $SCRATCH_MNT/foobar $XFS_IO_PROG -c "falloc 26450 665194" $SCRATCH_MNT/foobar $XFS_IO_PROG -c "truncate 542872" $SCRATCH_MNT/foobar $XFS_IO_PROG -c "fsync" $SCRATCH_MNT/foobar This results in the following file items in the fs tree: item 4 key (257 INODE_ITEM 0) itemoff 15879 itemsize 160 inode generation 6 transid 6 size 542872 block group 0 mode 100600 item 5 key (257 INODE_REF 256) itemoff 15863 itemsize 16 inode ref index 2 namelen 6 name: foobar item 6 key (257 EXTENT_DATA 0) itemoff 15810 itemsize 53 extent data disk byte 0 nr 0 gen 6 extent data offset 0 nr 24576 ram 266240 extent compression 0 item 7 key (257 EXTENT_DATA 24576) itemoff 15757 itemsize 53 prealloc data disk byte 12849152 nr 241664 gen 6 prealloc data offset 0 nr 241664 item 8 key (257 EXTENT_DATA 266240) itemoff 15704 itemsize 53 extent data disk byte 12845056 nr 4096 gen 6 extent data offset 0 nr 20480 ram 20480 extent compression 2 item 9 key (257 EXTENT_DATA 286720) itemoff 15651 itemsize 53 prealloc data disk byte 13090816 nr 405504 gen 6 prealloc data offset 0 nr 258048 The on disk extent at offset 266240 (which corresponds to 1 single disk block), contains 5 compressed chunks of file data. Each of the first 4 compress 4096 bytes of file data, while the last one only compresses 3024 bytes of file data. Therefore a read into the file region [285648 ; 286720[ (length = 4096 - 3024 = 1072 bytes) should always return zeroes (our next extent is a prealloc one). The solution here is the compression code path to zero the remaining (untouched) bytes of the last page it uncompressed data into, as the information about how much space the file data consumes in the last page is not known in the upper layer fs/btrfs/extent_io.c:__do_readpage(). In __do_readpage we were correctly zeroing the remainder of the page but only if it corresponds to the last page of the inode and if the inode's size is not a multiple of the page size. This would cause not only returning random data on reads, but also permanently storing random data when updating parts of the region that should be zeroed. For the example above, it means updating a single byte in the region [285648 ; 286720[ would store that byte correctly but also store random data on disk. A test case for xfstests follows soon. Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com> Signed-off-by: Chris Mason <clm@fb.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-02-06Btrfs: handle EAGAIN case properly in btrfs_drop_snapshot()Wang Shilong1-1/+1
commit 90515e7f5d7d24cbb2a4038a3f1b5cfa2921aa17 upstream. We may return early in btrfs_drop_snapshot(), we shouldn't call btrfs_std_err() for this case, fix it. 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> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-10-14Btrfs: change how we queue blocks for backref checkingJosef Bacik1-7/+7
commit b6c60c8018c4e9beb2f83fc82c09f9d033766571 upstream. Previously we only added blocks to the list to have their backrefs checked if the level of the block is right above the one we are searching for. This is because we want to make sure we don't add the entire path up to the root to the lists to make sure we process things one at a time. This assumes that if any blocks in the path to the root are going to be not checked (shared in other words) then they will be in the level right above the current block on up. This isn't quite right though since we can have blocks higher up the list that are shared because they are attached to a reloc root. But we won't add this block to be checked and then later on we will BUG_ON(!upper->checked). So instead keep track of wether or not we've queued a block to be checked in this current search, and if we haven't go ahead and queue it to be checked. This patch fixed the panic I was seeing where we BUG_ON(!upper->checked). Thanks, Signed-off-by: Josef Bacik <jbacik@fusionio.com> Signed-off-by: Chris Mason <chris.mason@fusionio.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-04Btrfs: re-add root to dead root list if we stop dropping itJosef Bacik1-0/+11
commit d29a9f629e009c9b90e5859bce581070fd6247fc upstream. If we stop dropping a root for whatever reason we need to add it back to the dead root list so that we will re-start the dropping next transaction commit. The other case this happens is if we recover a drop because we will add a root without adding it to the fs radix tree, so we can leak it's root and commit root extent buffer, adding this to the dead root list makes this cleanup happen. Thanks, Reported-by: Alex Lyakas <alex.btrfs@zadarastorage.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-04Btrfs: fix lock leak when resuming snapshot deletionJosef Bacik1-0/+2
commit fec386ac1428f9c0e672df952cbca5cebd4e4e2f upstream. We aren't setting path->locks[level] when we resume a snapshot deletion which means we won't unlock the buffer when we free the path. This causes deadlocks if we happen to re-allocate the block before we've evicted the extent buffer from cache. Thanks, Reported-by: Alex Lyakas <alex.btrfs@zadarastorage.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-05-24btrfs: don't stop searching after encountering the wrong itemGabriel de Perthuis1-5/+5
commit 03b71c6ca6286625d8f1ed44aabab9b5bf5dac10 upstream. The search ioctl skips items that are too large for a result buffer, but inline items of a certain size occuring before any search result is found would trigger an overflow and stop the search entirely. Bug: https://bugzilla.kernel.org/show_bug.cgi?id=57641 Signed-off-by: Gabriel de Perthuis <g2p.code+btrfs@gmail.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-26Btrfs: make sure nbytes are right after log replayJosef Bacik1-6/+42
commit 4bc4bee4595662d8bff92180d5c32e3313a704b0 upstream. While trying to track down a tree log replay bug I noticed that fsck was always complaining about nbytes not being right for our fsynced file. That is because the new fsync stuff doesn't wait for ordered extents to complete, so the inodes nbytes are not necessarily updated properly when we log it. So to fix this we need to set nbytes to whatever it is on the inode that is on disk, so when we replay the extents we can just add the bytes that are being added as we replay the extent. This makes it work for the case that we have the wrong nbytes or the case that we logged everything and nbytes is actually correct. With this I'm no longer getting nbytes errors out of btrfsck. Signed-off-by: Josef Bacik <jbacik@fusionio.com> Signed-off-by: Chris Mason <chris.mason@fusionio.com> Signed-off-by: Lingzhu Xiang <lxiang@redhat.com> Reviewed-by: CAI Qian <caiqian@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-05Btrfs: fix space leak when we fail to reserve metadata spaceJosef Bacik1-6/+41
commit f4881bc7a83eff263789dd524b7c269d138d4af5 upstream. Dave reported a warning when running xfstest 275. We have been leaking delalloc metadata space when our reservations fail. This is because we were improperly calculating how much space to free for our checksum reservations. The problem is we would sometimes free up space that had already been freed in another thread and we would end up with negative usage for the delalloc space. This patch fixes the problem by calculating how much space the other threads would have already freed, and then calculate how much space we need to free had we not done the reservation at all, and then freeing any excess space. This makes xfstests 275 no longer have leaked space. Thanks Reported-by: David Sterba <dsterba@suse.cz> Signed-off-by: Josef Bacik <jbacik@fusionio.com> Signed-off-by: Lingzhu Xiang <lxiang@redhat.com> Reviewed-by: CAI Qian <caiqian@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-05Btrfs: don't drop path when printing out tree errors in scrubJosef Bacik1-1/+2
commit d8fe29e9dea8d7d61fd140d8779326856478fc62 upstream. A user reported a panic where we were panicing somewhere in tree_backref_for_extent from scrub_print_warning. He only captured the trace but looking at scrub_print_warning we drop the path right before we mess with the extent buffer to print out a bunch of stuff, which isn't right. So fix this by dropping the path after we use the eb if we need to. Thanks, Signed-off-by: Josef Bacik <jbacik@fusionio.com> Signed-off-by: Chris Mason <chris.mason@fusionio.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-05Btrfs: limit the global reserve to 512mbJosef Bacik1-1/+1
commit fdf30d1c1b386e1b73116cc7e0fb14e962b763b0 upstream. A user reported a problem where he was getting early ENOSPC with hundreds of gigs of free data space and 6 gigs of free metadata space. This is because the global block reserve was taking up the entire free metadata space. This is ridiculous, we have infrastructure in place to throttle if we start using too much of the global reserve, so instead of letting it get this huge just limit it to 512mb so that users can still get work done. This allowed the user to complete his rsync without issues. Thanks Reported-and-tested-by: Stefan Priebe <s.priebe@profihost.ag> Signed-off-by: Josef Bacik <jbacik@fusionio.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-04-05Btrfs: fix race between mmap writes and compressionChris Mason3-0/+49
commit 4adaa611020fa6ac65b0ac8db78276af4ec04e63 upstream. Btrfs uses page_mkwrite to ensure stable pages during crc calculations and mmap workloads. We call clear_page_dirty_for_io before we do any crcs, and this forces any application with the file mapped to wait for the crc to finish before it is allowed to change the file. With compression on, the clear_page_dirty_for_io step is happening after we've compressed the pages. This means the applications might be changing the pages while we are compressing them, and some of those modifications might not hit the disk. This commit adds the clear_page_dirty_for_io before compression starts and makes sure to redirty the page if we have to fallback to uncompressed IO as well. Signed-off-by: Chris Mason <chris.mason@fusionio.com> Reported-by: Alexandre Oliva <oliva@gnu.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-03-21btrfs: use rcu_barrier() to wait for bdev puts at unmountEric Sandeen1-0/+6
commit bc178622d40d87e75abc131007342429c9b03351 upstream. Doing this would reliably fail with -EBUSY for me: # mount /dev/sdb2 /mnt/scratch; umount /mnt/scratch; mkfs.btrfs -f /dev/sdb2 ... unable to open /dev/sdb2: Device or resource busy because mkfs.btrfs tries to open the device O_EXCL, and somebody still has it. Using systemtap to track bdev gets & puts shows a kworker thread doing a blkdev put after mkfs attempts a get; this is left over from the unmount path: btrfs_close_devices __btrfs_close_devices call_rcu(&device->rcu, free_device); free_device INIT_WORK(&device->rcu_work, __free_device); schedule_work(&device->rcu_work); so unmount might complete before __free_device fires & does its blkdev_put. Adding an rcu_barrier() to btrfs_close_devices() causes unmount to wait until all blkdev_put()s are done, and the device is truly free once unmount completes. Signed-off-by: Eric Sandeen <sandeen@redhat.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com> Signed-off-by: Chris Mason <chris.mason@fusionio.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-03-14btrfs: Init io_lock after cloning btrfs device structThomas Gleixner1-0/+1
commit 1cba0cdf5e4dbcd9e5fa5b54d7a028e55e2ca057 upstream. __btrfs_close_devices() clones btrfs device structs with memcpy(). Some of the fields in the clone are reinitialized, but it's missing to init io_lock. In mainline this goes unnoticed, but on RT it leaves the plist pointing to the original about to be freed lock struct. Initialize io_lock after cloning, so no references to the original struct are left. Reported-and-tested-by: Mike Galbraith <efault@gmx.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Chris Mason <chris.mason@fusionio.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-08-09Btrfs: call the ordered free operation without any locks heldChris Mason1-1/+8
commit e9fbcb42201c862fd6ab45c48ead4f47bb2dea9d upstream. Each ordered operation has a free callback, and this was called with the worker spinlock held. Josef made the free callback also call iput, which we can't do with the spinlock. This drops the spinlock for the free operation and grabs it again before moving through the rest of the list. We'll circle back around to this and find a cleaner way that doesn't bounce the lock around so much. Signed-off-by: Chris Mason <chris.mason@fusionio.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-07-16Btrfs: run delayed directory updates during log replayChris Mason1-0/+6
commit b6305567e7d31b0bec1b8cb9ec0cadd7f7086f5f upstream. While we are resolving directory modifications in the tree log, we are triggering delayed metadata updates to the filesystem btrees. This commit forces the delayed updates to run so the replay code can find any modifications done. It stops us from crashing because the directory deleltion replay expects items to be removed immediately from the tree. Signed-off-by: Chris Mason <chris.mason@fusionio.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-06-17Btrfs: fall back to non-inline if we don't have enough spaceJosef Bacik1-1/+4
commit 2adcac1a7331d93a17285804819caa96070b231f upstream. If cow_file_range_inline fails with ENOSPC we abort the transaction which isn't very nice. This really shouldn't be happening anyways but there's no sense in making it a horrible error when we can easily just go allocate normal data space for this stuff. Thanks, Signed-off-by: Josef Bacik <josef@redhat.com> Acked-by: Chris Mason <chris.mason@fusionio.com> Cc: Alexandre Oliva <oliva@lsd.ic.unicamp.br> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-05-06Merge branch 'for-linus' of ↵Linus Torvalds8-21/+47
git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs Pull btrfs fixes from Chris Mason: "The big ones here are a memory leak we introduced in rc1, and a scheduling while atomic if the transid on disk doesn't match the transid we expected. This happens for corrupt blocks, or out of date disks. It also fixes up the ioctl definition for our ioctl to resolve logical inode numbers. The __u32 was a merging error and doesn't match what we ship in the progs." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: Btrfs: avoid sleeping in verify_parent_transid while atomic Btrfs: fix crash in scrub repair code when device is missing btrfs: Fix mismatching struct members in ioctl.h Btrfs: fix page leak when allocing extent buffers Btrfs: Add properly locking around add_root_to_dirty_list
2012-05-06Btrfs: avoid sleeping in verify_parent_transid while atomicChris Mason5-17/+34
verify_parent_transid needs to lock the extent range to make sure no IO is underway, and so it can safely clear the uptodate bits if our checks fail. But, a few callers are using it with spinlocks held. Most of the time, the generation numbers are going to match, and we don't want to switch to a blocking lock just for the error case. This adds an atomic flag to verify_parent_transid, and changes it to return EAGAIN if it needs to block to properly verifiy things. Signed-off-by: Chris Mason <chris.mason@oracle.com>
2012-05-04Btrfs: fix crash in scrub repair code when device is missingStefan Behrens1-0/+7
Fix that when scrub tries to repair an I/O or checksum error and one of the devices containing the mirror is missing, it crashes in bio_add_page because the bdev is a NULL pointer for missing devices. Reported-by: Marco L. Crociani <marco.crociani@gmail.com> Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2012-05-04btrfs: Fix mismatching struct members in ioctl.hAlexander Block1-2/+2
Fix the size members of btrfs_ioctl_ino_path_args and btrfs_ioctl_logical_ino_args. The user space btrfs-progs utilities used __u64 and the kernel headers used __u32 before. Signed-off-by: Alexander Block <ablock84@googlemail.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2012-05-04Btrfs: fix page leak when allocing extent buffersJosef Bacik1-2/+2
If we happen to alloc a extent buffer and then alloc a page and notice that page is already attached to an extent buffer, we will only unlock it and free our existing eb. Any pages currently attached to that eb will be properly freed, but we don't do the page_cache_release() on the page where we noticed the other extent buffer which can cause us to leak pages and I hope cause the weird issues we've been seeing in this area. Thanks, Signed-off-by: Josef Bacik <josef@redhat.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2012-05-04Btrfs: Add properly locking around add_root_to_dirty_listChris Mason1-0/+2
add_root_to_dirty_list happens once at the very beginning of the transaction, but it is still racey. Signed-off-by: Chris Mason <chris.mason@oracle.com>
2012-04-28Merge branch 'for-linus' of ↵Linus Torvalds15-139/+148
git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs Pull btrfs fixes from Chris Mason: "This has our collection of bug fixes. I missed the last rc because I thought our patches were making NFS crash during my xfs test runs. Turns out it was an NFS client bug fixed by someone else while I tried to bisect it. All of these fixes are small, but some are fairly high impact. The biggest are fixes for our mount -o remount handling, a deadlock due to GFP_KERNEL allocations in readdir, and a RAID10 error handling bug. This was tested against both 3.3 and Linus' master as of this morning." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (26 commits) Btrfs: reduce lock contention during extent insertion Btrfs: avoid deadlocks from GFP_KERNEL allocations during btrfs_real_readdir Btrfs: Fix space checking during fs resize Btrfs: fix block_rsv and space_info lock ordering Btrfs: Prevent root_list corruption Btrfs: fix repair code for RAID10 Btrfs: do not start delalloc inodes during sync Btrfs: fix that check_int_data mount option was ignored Btrfs: don't count CRC or header errors twice while scrubbing Btrfs: fix btrfs_ioctl_dev_info() crash on missing device btrfs: don't return EINTR Btrfs: double unlock bug in error handling Btrfs: always store the mirror we read the eb from fs/btrfs/volumes.c: add missing free_fs_devices btrfs: fix early abort in 'remount' Btrfs: fix max chunk size check in chunk allocator Btrfs: add missing read locks in backref.c Btrfs: don't call free_extent_buffer twice in iterate_irefs Btrfs: Make free_ipath() deal gracefully with NULL pointers Btrfs: avoid possible use-after-free in clear_extent_bit() ...
2012-04-27Btrfs: reduce lock contention during extent insertionChris Mason1-2/+7
We're spending huge amounts of time on lock contention during end_io processing because we unconditionally assume we are overwriting an existing extent in the file for each IO. This checks to see if we are outside i_size, and if so, it uses a less expensive readonly search of the btree to look for existing extents. Signed-off-by: Chris Mason <chris.mason@oracle.com>
2012-04-27Btrfs: avoid deadlocks from GFP_KERNEL allocations during btrfs_real_readdirChris Mason1-29/+1
Btrfs has an optimization where it will preallocate dentries during readdir to fill in enough information to open the inode without an extra lookup. But, we're calling d_alloc, which is doing GFP_KERNEL allocations, and that leads to deadlocks because our readdir code has tree locks held. For now, disable this optimization. We'll fix the gfp mask in the next merge window. Signed-off-by: Chris Mason <chris.mason@oracle.com>
2012-04-27Btrfs: Fix space checking during fs resizeDaniel J Blueman1-1/+1
Fix out-of-space checking, addressing a warning and potential resource leak when resizing the filesystem down while allocating blocks. Signed-off-by: Daniel J Blueman <daniel@quora.org> Reviewed-by: Josef Bacik <josef@redhat.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2012-04-27Btrfs: fix block_rsv and space_info lock orderingStefan Behrens1-2/+2
may_commit_transaction() calls spin_lock(&space_info->lock); spin_lock(&delayed_rsv->lock); and update_global_block_rsv() calls spin_lock(&block_rsv->lock); spin_lock(&sinfo->lock); Lockdep complains about this at run time. Everywhere except in update_global_block_rsv(), the space_info lock is the outer lock, therefore the locking order in update_global_block_rsv() is changed. Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2012-04-27Btrfs: Prevent root_list corruptionDaniel J Blueman1-0/+2
I was seeing root_list corruption on unmount during fs resize in 3.4-rc4; add correct locking to address this. Signed-off-by: Daniel J Blueman <daniel@quora.org> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2012-04-27Btrfs: fix repair code for RAID10Jan Schmidt1-1/+2
btrfs_map_block sets mirror_num, so that the repair code knows eventually which device gave us the read error. For RAID10, mirror_num must be 1 or 2. Before this fix mirror_num was incorrectly related to our stripe index. Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2012-04-27Btrfs: do not start delalloc inodes during syncJosef Bacik1-1/+0
btrfs_start_delalloc_inodes will just walk the list of delalloc inodes and start writing them out, but it doesn't splice the list or anything so as long as somebody is doing work on the box you could end up in this section _forever_. So just remove it, it's not needed anyway since sync will start writeback on all inodes anyway, all we need to do is wait for ordered extents and then we can commit the transaction. In my horrible torture test sync goes from taking 4 minutes to about 1.5 minutes. Thanks, Signed-off-by: Josef Bacik <josef@redhat.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
2012-04-18Btrfs: fix that check_int_data mount option was ignoredStefan Behrens1-1/+1
The bitfield member mount_opt was too small by one bit to hold the mount option that enabled to include data extents in the integrity checker. Since the same issue happened when the BTRFS_MOUNT_PANIC_ON_FATAL_ERROR option was added (git rebase silently merges so that the increase of the size of the bitfield member is lost), the bit limit was removed entirely. Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
2012-04-18Btrfs: don't count CRC or header errors twice while scrubbingStefan Behrens1-15/+0
Each CRC or header error was counted twice, this is now fixed. Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
2012-04-18Btrfs: fix btrfs_ioctl_dev_info() crash on missing deviceStefan Behrens1-1/+4
When a filesystem is mounted with the degraded option, it is possible that some of the devices are not there. btrfs_ioctl_dev_info() crashs in this case because the device name is a NULL pointer. This ioctl was only used for scrub. Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
2012-04-18btrfs: don't return EINTRArne Jansen1-6/+3
It is basically a good thing if we are interruptible when waiting for free space, but the generality in which it is implemented currently leads to system calls being interruptible that are not documented this way. For example git can't handle interrupted unlink(), leading to corrupt repos under space pressure. Instead we raise the bar to only be interruptible by SIGKILL. Thanks to David Sterba for suggesting this. Signed-off-by: Arne Jansen <sensille@gmx.net>
2012-04-18Btrfs: double unlock bug in error handlingDan Carpenter1-0/+2
The caller expects this function to return with the lock held and releases it immediately on error. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
2012-04-18Btrfs: always store the mirror we read the eb fromJosef Bacik4-20/+17
A user reported a panic where we were trying to fix a bad mirror but the mirror number we were giving was 0, which is invalid. This is because we don't do the transid verification until after the read, so as far as the read code is concerned the read was a success. So instead store the mirror we read from so that if there is some failure post read we know which mirror to try next and which mirror needs to be fixed if we find a good copy of the block. Thanks, Signed-off-by: Josef Bacik <josef@redhat.com>
2012-04-18fs/btrfs/volumes.c: add missing free_fs_devicesJulia Lawall1-1/+3
Free fs_devices as done in the error-handling code just below. Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
2012-04-18btrfs: fix early abort in 'remount'Sergei Trofimovich1-2/+4
Cc: Jeff Mahoney <jeffm@suse.com> Cc: Chris Mason <chris.mason@oracle.com> Cc: Josef Bacik <josef@redhat.com> Signed-off-by: Sergei Trofimovich <slyfox@gentoo.org>