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2015-10-21btrfs: Move btrfs_raid_array to publicZhao Lei
This array is used to record attributes of each raid type, make it public, and many functions will benifit with this array. For example, num_tolerated_disk_barrier_failures(), we can avoid complex conditions in this function, and get raid attribute simply by accessing above array. It can also make code logic simple, reduce duplication code, and increase maintainability. Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com> Signed-off-by: David Sterba <dsterba@suse.com>
2015-10-21btrfs: use a single if() statement for one outcome in get_block_rsv()Alexandru Moise
Rather than have three separate if() statements for the same outcome we should just OR them together in the same if() statement. Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: Alexandru Moise <00moses.alexander00@gmail.com> Signed-off-by: David Sterba <dsterba@suse.com>
2015-10-21btrfs: memset cur_trans->delayed_refs to zeroAlexandru Moise
Use memset() to null out the btrfs_delayed_ref_root of btrfs_transaction instead of setting all the members to 0 by hand. Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: Alexandru Moise <00moses.alexander00@gmail.com> Signed-off-by: David Sterba <dsterba@suse.com>
2015-10-21btrfs: remove unnecessary list_delByongho Lee
We can safely iterate whole list items, without using list_del macro. So remove the list_del call. Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: Byongho Lee <bhlee.kernel@gmail.com> Signed-off-by: David Sterba <dsterba@suse.com>
2015-10-21btrfs: replace unnecessary list_for_each_entry_safe to list_for_each_entryByongho Lee
There is no removing list element while iterating over list. So, replace list_for_each_entry_safe to list_for_each_entry. Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: Byongho Lee <bhlee.kernel@gmail.com> Signed-off-by: David Sterba <dsterba@suse.com>
2015-10-21btrfs: trimming some start_transaction() code awayAlexandru Moise
Just call kmem_cache_zalloc() instead of calling kmem_cache_alloc(). We're just initializing most fields to 0, false and NULL later on _anyway_, so to make the code mode readable and potentially gain a bit of performance (completely untested claim), we should fill our btrfs_trans_handle with zeros on allocation then just initialize those five remaining fields (not counting the list_heads) as normal. Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: Alexandru Moise <00moses.alexander00@gmail.com> Signed-off-by: David Sterba <dsterba@suse.com>
2015-10-21btrfs: Fixed declaration of old_lenAlexandru Moise
old_len is used to store the return value of btrfs_item_size_nr(). The return value of btrfs_item_size_nr() is of type u32. To improve code correctness and avoid mixing signed and unsigned integers I've changed old_len to be of type u32 as well. Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: Alexandru Moise <00moses.alexander00@gmail.com> Signed-off-by: David Sterba <dsterba@suse.com>
2015-10-21btrfs: Fixed dsize and last_off declarationsAlexandru Moise
The return values of btrfs_item_offset_nr and btrfs_item_size_nr are of type u32. To avoid mixing signed and unsigned integers we should also declare dsize and last_off to be of type u32. Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: Alexandru Moise <00moses.alexander00@gmail.com> Signed-off-by: David Sterba <dsterba@suse.com>
2015-10-21Btrfs: btrfs_submit_bio_hook: Use btrfs_wq_endio_type values instead of ↵Chandan Rajendra
integer constants btrfs_submit_bio_hook() uses integer constants instead of values from "enum btrfs_wq_endio_type". Fix this. Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com> Signed-off-by: David Sterba <dsterba@suse.com>
2015-10-20btrfs: Avoid truncate tailing page if fallocate range doesn't exceed inode sizeQu Wenruo
Current code will always truncate tailing page if its alloc_start is smaller than inode size. For example, the file extent layout is like: 0 4K 8K 16K 32K |<-----Extent A---------------->| |<--Inode size: 18K---------->| But if calling fallocate even for range [0,4K), it will cause btrfs to re-truncate the range [16,32K), causing COW and a new extent. 0 4K 8K 16K 32K |///////| <- Fallocate call range |<-----Extent A-------->|<--B-->| The cause is quite easy, just a careless btrfs_truncate_inode() in a else branch without extra judgment. Fix it by add judgment on whether the fallocate range is beyond isize. Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com> Signed-off-by: Chris Mason <clm@fb.com>
2015-10-16Btrfs: fix truncation of compressed and inlined extentsFilipe Manana
When truncating a file to a smaller size which consists of an inline extent that is compressed, we did not discard (or made unusable) the data between the new file size and the old file size, wasting metadata space and allowing for the truncated data to be leaked and the data corruption/loss mentioned below. We were also not correctly decrementing the number of bytes used by the inode, we were setting it to zero, giving a wrong report for callers of the stat(2) syscall. The fsck tool also reported an error about a mismatch between the nbytes of the file versus the real space used by the file. Now because we weren't discarding the truncated region of the file, it was possible for a caller of the clone ioctl to actually read the data that was truncated, allowing for a security breach without requiring root access to the system, using only standard filesystem operations. The scenario is the following: 1) User A creates a file which consists of an inline and compressed extent with a size of 2000 bytes - the file is not accessible to any other users (no read, write or execution permission for anyone else); 2) The user truncates the file to a size of 1000 bytes; 3) User A makes the file world readable; 4) User B creates a file consisting of an inline extent of 2000 bytes; 5) User B issues a clone operation from user A's file into its own file (using a length argument of 0, clone the whole range); 6) User B now gets to see the 1000 bytes that user A truncated from its file before it made its file world readbale. User B also lost the bytes in the range [1000, 2000[ bytes from its own file, but that might be ok if his/her intention was reading stale data from user A that was never supposed to be public. Note that this contrasts with the case where we truncate a file from 2000 bytes to 1000 bytes and then truncate it back from 1000 to 2000 bytes. In this case reading any byte from the range [1000, 2000[ will return a value of 0x00, instead of the original data. This problem exists since the clone ioctl was added and happens both with and without my recent data loss and file corruption fixes for the clone ioctl (patch "Btrfs: fix file corruption and data loss after cloning inline extents"). So fix this by truncating the compressed inline extents as we do for the non-compressed case, which involves decompressing, if the data isn't already in the page cache, compressing the truncated version of the extent, writing the compressed content into the inline extent and then truncate it. The following test case for fstests reproduces the problem. In order for the test to pass both this fix and my previous fix for the clone ioctl that forbids cloning a smaller inline extent into a larger one, which is titled "Btrfs: fix file corruption and data loss after cloning inline extents", are needed. Without that other fix the test fails in a different way that does not leak the truncated data, instead part of destination file gets replaced with zeroes (because the destination file has a larger inline extent than the source). seq=`basename $0` seqres=$RESULT_DIR/$seq echo "QA output created by $seq" tmp=/tmp/$$ status=1 # failure is the default! trap "_cleanup; exit \$status" 0 1 2 3 15 _cleanup() { rm -f $tmp.* } # get standard environment, filters and checks . ./common/rc . ./common/filter # real QA test starts here _need_to_be_root _supported_fs btrfs _supported_os Linux _require_scratch _require_cloner rm -f $seqres.full _scratch_mkfs >>$seqres.full 2>&1 _scratch_mount "-o compress" # Create our test files. File foo is going to be the source of a clone operation # and consists of a single inline extent with an uncompressed size of 512 bytes, # while file bar consists of a single inline extent with an uncompressed size of # 256 bytes. For our test's purpose, it's important that file bar has an inline # extent with a size smaller than foo's inline extent. $XFS_IO_PROG -f -c "pwrite -S 0xa1 0 128" \ -c "pwrite -S 0x2a 128 384" \ $SCRATCH_MNT/foo | _filter_xfs_io $XFS_IO_PROG -f -c "pwrite -S 0xbb 0 256" $SCRATCH_MNT/bar | _filter_xfs_io # Now durably persist all metadata and data. We do this to make sure that we get # on disk an inline extent with a size of 512 bytes for file foo. sync # Now truncate our file foo to a smaller size. Because it consists of a # compressed and inline extent, btrfs did not shrink the inline extent to the # new size (if the extent was not compressed, btrfs would shrink it to 128 # bytes), it only updates the inode's i_size to 128 bytes. $XFS_IO_PROG -c "truncate 128" $SCRATCH_MNT/foo # Now clone foo's inline extent into bar. # This clone operation should fail with errno EOPNOTSUPP because the source # file consists only of an inline extent and the file's size is smaller than # the inline extent of the destination (128 bytes < 256 bytes). However the # clone ioctl was not prepared to deal with a file that has a size smaller # than the size of its inline extent (something that happens only for compressed # inline extents), resulting in copying the full inline extent from the source # file into the destination file. # # Note that btrfs' clone operation for inline extents consists of removing the # inline extent from the destination inode and copy the inline extent from the # source inode into the destination inode, meaning that if the destination # inode's inline extent is larger (N bytes) than the source inode's inline # extent (M bytes), some bytes (N - M bytes) will be lost from the destination # file. Btrfs could copy the source inline extent's data into the destination's # inline extent so that we would not lose any data, but that's currently not # done due to the complexity that would be needed to deal with such cases # (specially when one or both extents are compressed), returning EOPNOTSUPP, as # it's normally not a very common case to clone very small files (only case # where we get inline extents) and copying inline extents does not save any # space (unlike for normal, non-inlined extents). $CLONER_PROG -s 0 -d 0 -l 0 $SCRATCH_MNT/foo $SCRATCH_MNT/bar # Now because the above clone operation used to succeed, and due to foo's inline # extent not being shinked by the truncate operation, our file bar got the whole # inline extent copied from foo, making us lose the last 128 bytes from bar # which got replaced by the bytes in range [128, 256[ from foo before foo was # truncated - in other words, data loss from bar and being able to read old and # stale data from foo that should not be possible to read anymore through normal # filesystem operations. Contrast with the case where we truncate a file from a # size N to a smaller size M, truncate it back to size N and then read the range # [M, N[, we should always get the value 0x00 for all the bytes in that range. # We expected the clone operation to fail with errno EOPNOTSUPP and therefore # not modify our file's bar data/metadata. So its content should be 256 bytes # long with all bytes having the value 0xbb. # # Without the btrfs bug fix, the clone operation succeeded and resulted in # leaking truncated data from foo, the bytes that belonged to its range # [128, 256[, and losing data from bar in that same range. So reading the # file gave us the following content: # # 0000000 a1 a1 a1 a1 a1 a1 a1 a1 a1 a1 a1 a1 a1 a1 a1 a1 # * # 0000200 2a 2a 2a 2a 2a 2a 2a 2a 2a 2a 2a 2a 2a 2a 2a 2a # * # 0000400 echo "File bar's content after the clone operation:" od -t x1 $SCRATCH_MNT/bar # Also because the foo's inline extent was not shrunk by the truncate # operation, btrfs' fsck, which is run by the fstests framework everytime a # test completes, failed reporting the following error: # # root 5 inode 257 errors 400, nbytes wrong status=0 exit Cc: stable@vger.kernel.org Signed-off-by: Filipe Manana <fdmanana@suse.com>
2015-10-16Merge branch 'for-linus-4.3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs Pull btrfs fixes from Chris Mason: "I have two more bug fixes for btrfs. My commit fixes a bug we hit last week at FB, a combination of lots of hard links and an admin command to resolve inode numbers. Dave is adding checks to make sure balance on current kernels ignores filters it doesn't understand. The penalty for being wrong is just doing more work (not crashing etc), but it's a good fix" * 'for-linus-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: btrfs: fix use after free iterating extrefs btrfs: check unsupported filters in balance arguments
2015-10-14Btrfs: fix double range unlock of hole region when reading pageFilipe Manana
If when reading a page we find a hole and our caller had already locked the range (bio flags has the bit EXTENT_BIO_PARENT_LOCKED set), we end up unlocking the hole's range and then later our caller unlocks it again, which might have already been locked by some other task once the first unlock happened. Currently this can only happen during a call to the extent_same ioctl, as it's the only caller of __do_readpage() that sets the bit EXTENT_BIO_PARENT_LOCKED for bio flags. Fix this by leaving the unlock exclusively to the caller. Signed-off-by: Filipe Manana <fdmanana@suse.com>
2015-10-14Btrfs: fix file corruption and data loss after cloning inline extentsFilipe Manana
Currently the clone ioctl allows to clone an inline extent from one file to another that already has other (non-inlined) extents. This is a problem because btrfs is not designed to deal with files having inline and regular extents, if a file has an inline extent then it must be the only extent in the file and must start at file offset 0. Having a file with an inline extent followed by regular extents results in EIO errors when doing reads or writes against the first 4K of the file. Also, the clone ioctl allows one to lose data if the source file consists of a single inline extent, with a size of N bytes, and the destination file consists of a single inline extent with a size of M bytes, where we have M > N. In this case the clone operation removes the inline extent from the destination file and then copies the inline extent from the source file into the destination file - we lose the M - N bytes from the destination file, a read operation will get the value 0x00 for any bytes in the the range [N, M] (the destination inode's i_size remained as M, that's why we can read past N bytes). So fix this by not allowing such destructive operations to happen and return errno EOPNOTSUPP to user space. Currently the fstest btrfs/035 tests the data loss case but it totally ignores this - i.e. expects the operation to succeed and does not check the we got data loss. The following test case for fstests exercises all these cases that result in file corruption and data loss: seq=`basename $0` seqres=$RESULT_DIR/$seq echo "QA output created by $seq" tmp=/tmp/$$ status=1 # failure is the default! trap "_cleanup; exit \$status" 0 1 2 3 15 _cleanup() { rm -f $tmp.* } # get standard environment, filters and checks . ./common/rc . ./common/filter # real QA test starts here _need_to_be_root _supported_fs btrfs _supported_os Linux _require_scratch _require_cloner _require_btrfs_fs_feature "no_holes" _require_btrfs_mkfs_feature "no-holes" rm -f $seqres.full test_cloning_inline_extents() { local mkfs_opts=$1 local mount_opts=$2 _scratch_mkfs $mkfs_opts >>$seqres.full 2>&1 _scratch_mount $mount_opts # File bar, the source for all the following clone operations, consists # of a single inline extent (50 bytes). $XFS_IO_PROG -f -c "pwrite -S 0xbb 0 50" $SCRATCH_MNT/bar \ | _filter_xfs_io # Test cloning into a file with an extent (non-inlined) where the # destination offset overlaps that extent. It should not be possible to # clone the inline extent from file bar into this file. $XFS_IO_PROG -f -c "pwrite -S 0xaa 0K 16K" $SCRATCH_MNT/foo \ | _filter_xfs_io $CLONER_PROG -s 0 -d 0 -l 0 $SCRATCH_MNT/bar $SCRATCH_MNT/foo # Doing IO against any range in the first 4K of the file should work. # Due to a past clone ioctl bug which allowed cloning the inline extent, # these operations resulted in EIO errors. echo "File foo data after clone operation:" # All bytes should have the value 0xaa (clone operation failed and did # not modify our file). od -t x1 $SCRATCH_MNT/foo $XFS_IO_PROG -c "pwrite -S 0xcc 0 100" $SCRATCH_MNT/foo | _filter_xfs_io # Test cloning the inline extent against a file which has a hole in its # first 4K followed by a non-inlined extent. It should not be possible # as well to clone the inline extent from file bar into this file. $XFS_IO_PROG -f -c "pwrite -S 0xdd 4K 12K" $SCRATCH_MNT/foo2 \ | _filter_xfs_io $CLONER_PROG -s 0 -d 0 -l 0 $SCRATCH_MNT/bar $SCRATCH_MNT/foo2 # Doing IO against any range in the first 4K of the file should work. # Due to a past clone ioctl bug which allowed cloning the inline extent, # these operations resulted in EIO errors. echo "File foo2 data after clone operation:" # All bytes should have the value 0x00 (clone operation failed and did # not modify our file). od -t x1 $SCRATCH_MNT/foo2 $XFS_IO_PROG -c "pwrite -S 0xee 0 90" $SCRATCH_MNT/foo2 | _filter_xfs_io # Test cloning the inline extent against a file which has a size of zero # but has a prealloc extent. It should not be possible as well to clone # the inline extent from file bar into this file. $XFS_IO_PROG -f -c "falloc -k 0 1M" $SCRATCH_MNT/foo3 | _filter_xfs_io $CLONER_PROG -s 0 -d 0 -l 0 $SCRATCH_MNT/bar $SCRATCH_MNT/foo3 # Doing IO against any range in the first 4K of the file should work. # Due to a past clone ioctl bug which allowed cloning the inline extent, # these operations resulted in EIO errors. echo "First 50 bytes of foo3 after clone operation:" # Should not be able to read any bytes, file has 0 bytes i_size (the # clone operation failed and did not modify our file). od -t x1 $SCRATCH_MNT/foo3 $XFS_IO_PROG -c "pwrite -S 0xff 0 90" $SCRATCH_MNT/foo3 | _filter_xfs_io # Test cloning the inline extent against a file which consists of a # single inline extent that has a size not greater than the size of # bar's inline extent (40 < 50). # It should be possible to do the extent cloning from bar to this file. $XFS_IO_PROG -f -c "pwrite -S 0x01 0 40" $SCRATCH_MNT/foo4 \ | _filter_xfs_io $CLONER_PROG -s 0 -d 0 -l 0 $SCRATCH_MNT/bar $SCRATCH_MNT/foo4 # Doing IO against any range in the first 4K of the file should work. echo "File foo4 data after clone operation:" # Must match file bar's content. od -t x1 $SCRATCH_MNT/foo4 $XFS_IO_PROG -c "pwrite -S 0x02 0 90" $SCRATCH_MNT/foo4 | _filter_xfs_io # Test cloning the inline extent against a file which consists of a # single inline extent that has a size greater than the size of bar's # inline extent (60 > 50). # It should not be possible to clone the inline extent from file bar # into this file. $XFS_IO_PROG -f -c "pwrite -S 0x03 0 60" $SCRATCH_MNT/foo5 \ | _filter_xfs_io $CLONER_PROG -s 0 -d 0 -l 0 $SCRATCH_MNT/bar $SCRATCH_MNT/foo5 # Reading the file should not fail. echo "File foo5 data after clone operation:" # Must have a size of 60 bytes, with all bytes having a value of 0x03 # (the clone operation failed and did not modify our file). od -t x1 $SCRATCH_MNT/foo5 # Test cloning the inline extent against a file which has no extents but # has a size greater than bar's inline extent (16K > 50). # It should not be possible to clone the inline extent from file bar # into this file. $XFS_IO_PROG -f -c "truncate 16K" $SCRATCH_MNT/foo6 | _filter_xfs_io $CLONER_PROG -s 0 -d 0 -l 0 $SCRATCH_MNT/bar $SCRATCH_MNT/foo6 # Reading the file should not fail. echo "File foo6 data after clone operation:" # Must have a size of 16K, with all bytes having a value of 0x00 (the # clone operation failed and did not modify our file). od -t x1 $SCRATCH_MNT/foo6 # Test cloning the inline extent against a file which has no extents but # has a size not greater than bar's inline extent (30 < 50). # It should be possible to clone the inline extent from file bar into # this file. $XFS_IO_PROG -f -c "truncate 30" $SCRATCH_MNT/foo7 | _filter_xfs_io $CLONER_PROG -s 0 -d 0 -l 0 $SCRATCH_MNT/bar $SCRATCH_MNT/foo7 # Reading the file should not fail. echo "File foo7 data after clone operation:" # Must have a size of 50 bytes, with all bytes having a value of 0xbb. od -t x1 $SCRATCH_MNT/foo7 # Test cloning the inline extent against a file which has a size not # greater than the size of bar's inline extent (20 < 50) but has # a prealloc extent that goes beyond the file's size. It should not be # possible to clone the inline extent from bar into this file. $XFS_IO_PROG -f -c "falloc -k 0 1M" \ -c "pwrite -S 0x88 0 20" \ $SCRATCH_MNT/foo8 | _filter_xfs_io $CLONER_PROG -s 0 -d 0 -l 0 $SCRATCH_MNT/bar $SCRATCH_MNT/foo8 echo "File foo8 data after clone operation:" # Must have a size of 20 bytes, with all bytes having a value of 0x88 # (the clone operation did not modify our file). od -t x1 $SCRATCH_MNT/foo8 _scratch_unmount } echo -e "\nTesting without compression and without the no-holes feature...\n" test_cloning_inline_extents echo -e "\nTesting with compression and without the no-holes feature...\n" test_cloning_inline_extents "" "-o compress" echo -e "\nTesting without compression and with the no-holes feature...\n" test_cloning_inline_extents "-O no-holes" "" echo -e "\nTesting with compression and with the no-holes feature...\n" test_cloning_inline_extents "-O no-holes" "-o compress" status=0 exit Cc: stable@vger.kernel.org Signed-off-by: Filipe Manana <fdmanana@suse.com>
2015-10-13btrfs: fix use after free iterating extrefsChris Mason
The code for btrfs inode-resolve has never worked properly for files with enough hard links to trigger extrefs. It was trying to get the leaf out of a path after freeing the path: btrfs_release_path(path); leaf = path->nodes[0]; item_size = btrfs_item_size_nr(leaf, slot); The fix here is to use the extent buffer we cloned just a little higher up to avoid deadlocks caused by using the leaf in the path. Signed-off-by: Chris Mason <clm@fb.com> cc: stable@vger.kernel.org # v3.7+ cc: Mark Fasheh <mfasheh@suse.de> Reviewed-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: Mark Fasheh <mfasheh@suse.de>
2015-10-13btrfs: check unsupported filters in balance argumentsDavid Sterba
We don't verify that all the balance filter arguments supplemented by the flags are actually known to the kernel. Thus we let it silently pass and do nothing. At the moment this means only the 'limit' filter, but we're going to add a few more soon so it's better to have that fixed. Also in older stable kernels so that it works with newer userspace tools. Cc: stable@vger.kernel.org # 3.16+ Signed-off-by: David Sterba <dsterba@suse.com> Signed-off-by: Chris Mason <clm@fb.com>
2015-10-13btrfs: fix resending received snapshot with parentRobin Ruede
This fixes a regression introduced by 37b8d27d between v4.1 and v4.2. When a snapshot is received, its received_uuid is set to the original uuid of the subvolume. When that snapshot is then resent to a third filesystem, it's received_uuid is set to the second uuid instead of the original one. The same was true for the parent_uuid. This behaviour was partially changed in 37b8d27d, but in that patch only the parent_uuid was taken from the real original, not the uuid itself, causing the search for the parent to fail in the case below. This happens for example when trying to send a series of linked snapshots (e.g. created by snapper) from the backup file system back to the original one. The following commands reproduce the issue in v4.2.1 (no error in 4.1.6) # setup three test file systems for i in 1 2 3; do truncate -s 50M fs$i mkfs.btrfs fs$i mkdir $i mount fs$i $i done echo "content" > 1/testfile btrfs su snapshot -r 1/ 1/snap1 echo "changed content" > 1/testfile btrfs su snapshot -r 1/ 1/snap2 # works fine: btrfs send 1/snap1 | btrfs receive 2/ btrfs send -p 1/snap1 1/snap2 | btrfs receive 2/ # ERROR: could not find parent subvolume btrfs send 2/snap1 | btrfs receive 3/ btrfs send -p 2/snap1 2/snap2 | btrfs receive 3/ Signed-off-by: Robin Ruede <rruede+git@gmail.com> Fixes: 37b8d27de5d0 ("Btrfs: use received_uuid of parent during send") Cc: stable@vger.kernel.org # v4.2+ Reviewed-by: Filipe Manana <fdmanana@suse.com> Tested-by: Ed Tomlinson <edt@aei.ca>
2015-10-13Btrfs: send, fix file corruption due to incorrect cloning operationsFilipe Manana
If we have a file that shares an extent with other files, when processing the extent item relative to a shared extent, we blindly issue a clone operation that will target a length matching the length in the extent item and uses as a source some other file the receiver already has and points to the same extent. However that range in the other file might not exclusively point only to the shared extent, and so using that length will result in the receiver getting a file with different data from the one in the send snapshot. This issue happened both for incremental and full send operations. So fix this by issuing clone operations with lengths that don't cover regions of the source file that point to different extents (or have holes). The following test case for fstests reproduces the problem. seq=`basename $0` seqres=$RESULT_DIR/$seq echo "QA output created by $seq" tmp=/tmp/$$ status=1 # failure is the default! trap "_cleanup; exit \$status" 0 1 2 3 15 _cleanup() { rm -fr $send_files_dir rm -f $tmp.* } # get standard environment, filters and checks . ./common/rc . ./common/filter # real QA test starts here _supported_fs btrfs _supported_os Linux _require_scratch _need_to_be_root _require_cp_reflink _require_xfs_io_command "fpunch" send_files_dir=$TEST_DIR/btrfs-test-$seq rm -f $seqres.full rm -fr $send_files_dir mkdir $send_files_dir _scratch_mkfs >>$seqres.full 2>&1 _scratch_mount # Create our test file with a single 100K extent. $XFS_IO_PROG -f -c "pwrite -S 0xaa 0K 100K" \ $SCRATCH_MNT/foo | _filter_xfs_io # Clone our file into a new file named bar. cp --reflink=always $SCRATCH_MNT/foo $SCRATCH_MNT/bar # Now overwrite parts of our foo file. $XFS_IO_PROG -c "pwrite -S 0xbb 50K 10K" \ -c "pwrite -S 0xcc 90K 10K" \ -c "fpunch 70K 10k" \ $SCRATCH_MNT/foo | _filter_xfs_io _run_btrfs_util_prog subvolume snapshot -r $SCRATCH_MNT \ $SCRATCH_MNT/snap echo "File digests in the original filesystem:" md5sum $SCRATCH_MNT/snap/foo | _filter_scratch md5sum $SCRATCH_MNT/snap/bar | _filter_scratch _run_btrfs_util_prog send $SCRATCH_MNT/snap -f $send_files_dir/1.snap # Now recreate the filesystem by receiving the send stream and verify # we get the same file contents that the original filesystem had. _scratch_unmount _scratch_mkfs >>$seqres.full 2>&1 _scratch_mount _run_btrfs_util_prog receive $SCRATCH_MNT -f $send_files_dir/1.snap # We expect the destination filesystem to have exactly the same file # data as the original filesystem. # The btrfs send implementation had a bug where it sent a clone # operation from file foo into file bar covering the whole [0, 100K[ # range after creating and writing the file foo. This was incorrect # because the file bar now included the updates done to file foo after # we cloned foo to bar, breaking the COW nature of reflink copies # (cloned extents). echo "File digests in the new filesystem:" md5sum $SCRATCH_MNT/snap/foo | _filter_scratch md5sum $SCRATCH_MNT/snap/bar | _filter_scratch status=0 exit Another test case that reproduces the problem when we have compressed extents: seq=`basename $0` seqres=$RESULT_DIR/$seq echo "QA output created by $seq" tmp=/tmp/$$ status=1 # failure is the default! trap "_cleanup; exit \$status" 0 1 2 3 15 _cleanup() { rm -fr $send_files_dir rm -f $tmp.* } # get standard environment, filters and checks . ./common/rc . ./common/filter # real QA test starts here _supported_fs btrfs _supported_os Linux _require_scratch _need_to_be_root _require_cp_reflink send_files_dir=$TEST_DIR/btrfs-test-$seq rm -f $seqres.full rm -fr $send_files_dir mkdir $send_files_dir _scratch_mkfs >>$seqres.full 2>&1 _scratch_mount "-o compress" # Create our file with an extent of 100K starting at file offset 0K. $XFS_IO_PROG -f -c "pwrite -S 0xaa 0K 100K" \ -c "fsync" \ $SCRATCH_MNT/foo | _filter_xfs_io # Rewrite part of the previous extent (its first 40K) and write a new # 100K extent starting at file offset 100K. $XFS_IO_PROG -c "pwrite -S 0xbb 0K 40K" \ -c "pwrite -S 0xcc 100K 100K" \ $SCRATCH_MNT/foo | _filter_xfs_io # Our file foo now has 3 file extent items in its metadata: # # 1) One covering the file range 0 to 40K; # 2) One covering the file range 40K to 100K, which points to the first # extent we wrote to the file and has a data offset field with value # 40K (our file no longer uses the first 40K of data from that # extent); # 3) One covering the file range 100K to 200K. # Now clone our file foo into file bar. cp --reflink=always $SCRATCH_MNT/foo $SCRATCH_MNT/bar # Create our snapshot for the send operation. _run_btrfs_util_prog subvolume snapshot -r $SCRATCH_MNT \ $SCRATCH_MNT/snap echo "File digests in the original filesystem:" md5sum $SCRATCH_MNT/snap/foo | _filter_scratch md5sum $SCRATCH_MNT/snap/bar | _filter_scratch _run_btrfs_util_prog send $SCRATCH_MNT/snap -f $send_files_dir/1.snap # Now recreate the filesystem by receiving the send stream and verify we # get the same file contents that the original filesystem had. # Btrfs send used to issue a clone operation from foo's range # [80K, 140K[ to bar's range [40K, 100K[ when cloning the extent pointed # to by foo's second file extent item, this was incorrect because of bad # accounting of the file extent item's data offset field. The correct # range to clone from should have been [40K, 100K[. _scratch_unmount _scratch_mkfs >>$seqres.full 2>&1 _scratch_mount "-o compress" _run_btrfs_util_prog receive $SCRATCH_MNT -f $send_files_dir/1.snap echo "File digests in the new filesystem:" # Must match the digests we got in the original filesystem. md5sum $SCRATCH_MNT/snap/foo | _filter_scratch md5sum $SCRATCH_MNT/snap/bar | _filter_scratch status=0 exit Signed-off-by: Filipe Manana <fdmanana@suse.com>
2015-10-12Merge branch 'fix/waitqueue-barriers' of ↵Chris Mason
git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux into for-linus-4.4
2015-10-12Merge branch 'anand/sysfs-updates-v4.3-rc3' of ↵Chris Mason
git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux into for-linus-4.4 Signed-off-by: Chris Mason <clm@fb.com>
2015-10-12Merge branch 'cleanup/messages' of ↵Chris Mason
git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux into for-linus-4.4
2015-10-10btrfs: comment the rest of implicit barriers before waitqueue_activeDavid Sterba
There are atomic operations that imply the barrier for waitqueue_active mixed in an if-condition. Signed-off-by: David Sterba <dsterba@suse.com>
2015-10-10btrfs: remove extra barrier before waitqueue_activeDavid Sterba
Removing barriers is scary, but a call to atomic_dec_and_test implies a barrier, so we don't need to issue another one. Signed-off-by: David Sterba <dsterba@suse.com>
2015-10-10btrfs: add comments to barriers before waitqueue_activeDavid Sterba
Reduce number of undocumented barriers out there. Signed-off-by: David Sterba <dsterba@suse.com>
2015-10-10btrfs: comment waitqueue_active implied by locksDavid Sterba
Suggested-by: Chris Mason <clm@fb.com> Signed-off-by: David Sterba <dsterba@suse.com>
2015-10-10btrfs: add barrier for waitqueue_active in clear_btree_io_treeDavid Sterba
waitqueue_active should be preceded by a barrier, in this function we don't need to call it all the time. Signed-off-by: David Sterba <dsterba@suse.com>
2015-10-10btrfs: remove waitqueue_active check from btrfs_rm_dev_replace_unblockedDavid Sterba
Normally the waitqueue_active would need a barrier, but this is not necessary here because it's not a performance sensitive context and we can call wake_up directly. Suggested-by: Chris Mason <clm@fb.com> Signed-off-by: David Sterba <dsterba@suse.com>
2015-10-09Merge branch 'for-linus-4.3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs Pull btrfs fixes from Chris Mason: "These are small and assorted. Neil's is the oldest, I dropped the ball thinking he was going to send it in" * 'for-linus-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: Btrfs: support NFSv2 export Btrfs: open_ctree: Fix possible memory leak Btrfs: fix deadlock when finalizing block group creation Btrfs: update fix for read corruption of compressed and shared extents Btrfs: send, fix corner case for reference overwrite detection
2015-10-08btrfs: switch more printks to our helpersDavid Sterba
Convert the simple cases, not all functions provide a way to reach the fs_info. Also skipped debugging messages (print-tree, integrity checker and pr_debug) and messages that are printed from possibly unfinished mount. Signed-off-by: David Sterba <dsterba@suse.com>
2015-10-08btrfs: switch message printers to ratelimited variantsDavid Sterba
Signed-off-by: David Sterba <dsterba@suse.com>
2015-10-08btrfs: introduce ratelimited variants of message printing functionsDavid Sterba
Signed-off-by: David Sterba <dsterba@suse.com>
2015-10-08btrfs: switch message printers to ratelimited _in_rcu variantsDavid Sterba
Signed-off-by: David Sterba <dsterba@suse.com>
2015-10-08btrfs: introduce ratelimited _in_rcu variants of message printing functionsDavid Sterba
Signed-off-by: David Sterba <dsterba@suse.com>
2015-10-08btrfs: switch message printers to _in_rcu variantsDavid Sterba
Signed-off-by: David Sterba <dsterba@suse.com>
2015-10-08btrfs: introduce _in_rcu variants of message printing functionsDavid Sterba
Due to the missing variants there are messages that lack the information printed by btrfs_info etc helpers. Signed-off-by: David Sterba <dsterba@suse.com>
2015-10-06BTRFS: support NFSv2 exportNeilBrown
The "fh_len" passed to ->fh_to_* is not guaranteed to be that same as that returned by encode_fh - it may be larger. With NFSv2, the filehandle is fixed length, so it may appear longer than expected and be zero-padded. So we must test that fh_len is at least some value, not exactly equal to it. Signed-off-by: NeilBrown <neilb@suse.de> Acked-by: David Sterba <dsterba@suse.cz>
2015-10-06Btrfs: open_ctree: Fix possible memory leakchandan
After reading one of chunk or tree root tree's root node from disk, if the root node does not have EXTENT_BUFFER_UPTODATE flag set, we fail to release the memory used by the root node. Fix this. Signed-off-by: Chandan Rajendra <chandan@linux.vnet.ibm.com>
2015-10-05Btrfs: fix deadlock when finalizing block group creationFilipe Manana
Josef ran into a deadlock while a transaction handle was finalizing the creation of its block groups, which produced the following trace: [260445.593112] fio D ffff88022a9df468 0 8924 4518 0x00000084 [260445.593119] ffff88022a9df468 ffffffff81c134c0 ffff880429693c00 ffff88022a9df488 [260445.593126] ffff88022a9e0000 ffff8803490d7b00 ffff8803490d7b18 ffff88022a9df4b0 [260445.593132] ffff8803490d7af8 ffff88022a9df488 ffffffff8175a437 ffff8803490d7b00 [260445.593137] Call Trace: [260445.593145] [<ffffffff8175a437>] schedule+0x37/0x80 [260445.593189] [<ffffffffa0850f37>] btrfs_tree_lock+0xa7/0x1f0 [btrfs] [260445.593197] [<ffffffff810db7c0>] ? prepare_to_wait_event+0xf0/0xf0 [260445.593225] [<ffffffffa07eac44>] btrfs_lock_root_node+0x34/0x50 [btrfs] [260445.593253] [<ffffffffa07eff6b>] btrfs_search_slot+0x88b/0xa00 [btrfs] [260445.593295] [<ffffffffa08389df>] ? free_extent_buffer+0x4f/0x90 [btrfs] [260445.593324] [<ffffffffa07f1a06>] btrfs_insert_empty_items+0x66/0xc0 [btrfs] [260445.593351] [<ffffffffa07ea94a>] ? btrfs_alloc_path+0x1a/0x20 [btrfs] [260445.593394] [<ffffffffa08403b9>] btrfs_finish_chunk_alloc+0x1c9/0x570 [btrfs] [260445.593427] [<ffffffffa08002ab>] btrfs_create_pending_block_groups+0x11b/0x200 [btrfs] [260445.593459] [<ffffffffa0800964>] do_chunk_alloc+0x2a4/0x2e0 [btrfs] [260445.593491] [<ffffffffa0803815>] find_free_extent+0xa55/0xd90 [btrfs] [260445.593524] [<ffffffffa0803c22>] btrfs_reserve_extent+0xd2/0x220 [btrfs] [260445.593532] [<ffffffff8119fe5d>] ? account_page_dirtied+0xdd/0x170 [260445.593564] [<ffffffffa0803e78>] btrfs_alloc_tree_block+0x108/0x4a0 [btrfs] [260445.593597] [<ffffffffa080c9de>] ? btree_set_page_dirty+0xe/0x10 [btrfs] [260445.593626] [<ffffffffa07eb5cd>] __btrfs_cow_block+0x12d/0x5b0 [btrfs] [260445.593654] [<ffffffffa07ebbff>] btrfs_cow_block+0x11f/0x1c0 [btrfs] [260445.593682] [<ffffffffa07ef8c7>] btrfs_search_slot+0x1e7/0xa00 [btrfs] [260445.593724] [<ffffffffa08389df>] ? free_extent_buffer+0x4f/0x90 [btrfs] [260445.593752] [<ffffffffa07f1a06>] btrfs_insert_empty_items+0x66/0xc0 [btrfs] [260445.593830] [<ffffffffa07ea94a>] ? btrfs_alloc_path+0x1a/0x20 [btrfs] [260445.593905] [<ffffffffa08403b9>] btrfs_finish_chunk_alloc+0x1c9/0x570 [btrfs] [260445.593946] [<ffffffffa08002ab>] btrfs_create_pending_block_groups+0x11b/0x200 [btrfs] [260445.593990] [<ffffffffa0815798>] btrfs_commit_transaction+0xa8/0xb40 [btrfs] [260445.594042] [<ffffffffa085abcd>] ? btrfs_log_dentry_safe+0x6d/0x80 [btrfs] [260445.594089] [<ffffffffa082bc84>] btrfs_sync_file+0x294/0x350 [btrfs] [260445.594115] [<ffffffff8123e29b>] vfs_fsync_range+0x3b/0xa0 [260445.594133] [<ffffffff81023891>] ? syscall_trace_enter_phase1+0x131/0x180 [260445.594149] [<ffffffff8123e35d>] do_fsync+0x3d/0x70 [260445.594169] [<ffffffff81023bb8>] ? syscall_trace_leave+0xb8/0x110 [260445.594187] [<ffffffff8123e600>] SyS_fsync+0x10/0x20 [260445.594204] [<ffffffff8175de6e>] entry_SYSCALL_64_fastpath+0x12/0x71 This happened because the same transaction handle created a large number of block groups and while finalizing their creation (inserting new items and updating existing items in the chunk and device trees) a new metadata extent had to be allocated and no free space was found in the current metadata block groups, which made find_free_extent() attempt to allocate a new block group via do_chunk_alloc(). However at do_chunk_alloc() we ended up allocating a new system chunk too and exceeded the threshold of 2Mb of reserved chunk bytes, which makes do_chunk_alloc() enter the final part of block group creation again (at btrfs_create_pending_block_groups()) and attempt to lock again the root of the chunk tree when it's already write locked by the same task. Similarly we can deadlock on extent tree nodes/leafs if while we are running delayed references we end up creating a new metadata block group in order to allocate a new node/leaf for the extent tree (as part of a CoW operation or growing the tree), as btrfs_create_pending_block_groups inserts items into the extent tree as well. In this case we get the following trace: [14242.773581] fio D ffff880428ca3418 0 3615 3100 0x00000084 [14242.773588] ffff880428ca3418 ffff88042d66b000 ffff88042a03c800 ffff880428ca3438 [14242.773594] ffff880428ca4000 ffff8803e4b20190 ffff8803e4b201a8 ffff880428ca3460 [14242.773600] ffff8803e4b20188 ffff880428ca3438 ffffffff8175a437 ffff8803e4b20190 [14242.773606] Call Trace: [14242.773613] [<ffffffff8175a437>] schedule+0x37/0x80 [14242.773656] [<ffffffffa057ff07>] btrfs_tree_lock+0xa7/0x1f0 [btrfs] [14242.773664] [<ffffffff810db7c0>] ? prepare_to_wait_event+0xf0/0xf0 [14242.773692] [<ffffffffa0519c44>] btrfs_lock_root_node+0x34/0x50 [btrfs] [14242.773720] [<ffffffffa051ef6b>] btrfs_search_slot+0x88b/0xa00 [btrfs] [14242.773750] [<ffffffffa0520a06>] btrfs_insert_empty_items+0x66/0xc0 [btrfs] [14242.773758] [<ffffffff811ef4a2>] ? kmem_cache_alloc+0x1d2/0x200 [14242.773786] [<ffffffffa0520ad1>] btrfs_insert_item+0x71/0xf0 [btrfs] [14242.773818] [<ffffffffa052f292>] btrfs_create_pending_block_groups+0x102/0x200 [btrfs] [14242.773850] [<ffffffffa052f96e>] do_chunk_alloc+0x2ae/0x2f0 [btrfs] [14242.773934] [<ffffffffa0532825>] find_free_extent+0xa55/0xd90 [btrfs] [14242.773998] [<ffffffffa0532c22>] btrfs_reserve_extent+0xc2/0x1d0 [btrfs] [14242.774041] [<ffffffffa0532e38>] btrfs_alloc_tree_block+0x108/0x4a0 [btrfs] [14242.774078] [<ffffffffa051a5cd>] __btrfs_cow_block+0x12d/0x5b0 [btrfs] [14242.774118] [<ffffffffa051abff>] btrfs_cow_block+0x11f/0x1c0 [btrfs] [14242.774155] [<ffffffffa051e8c7>] btrfs_search_slot+0x1e7/0xa00 [btrfs] [14242.774194] [<ffffffffa0528021>] ? __btrfs_free_extent.isra.70+0x2e1/0xcb0 [btrfs] [14242.774235] [<ffffffffa0520a06>] btrfs_insert_empty_items+0x66/0xc0 [btrfs] [14242.774274] [<ffffffffa051994a>] ? btrfs_alloc_path+0x1a/0x20 [btrfs] [14242.774318] [<ffffffffa052c433>] __btrfs_run_delayed_refs+0xbb3/0x1020 [btrfs] [14242.774358] [<ffffffffa052f404>] btrfs_run_delayed_refs.part.78+0x74/0x280 [btrfs] [14242.774391] [<ffffffffa052f627>] btrfs_run_delayed_refs+0x17/0x20 [btrfs] [14242.774432] [<ffffffffa05be236>] commit_cowonly_roots+0x8d/0x2bd [btrfs] [14242.774474] [<ffffffffa059d07f>] ? __btrfs_run_delayed_items+0x1cf/0x210 [btrfs] [14242.774516] [<ffffffffa05adac3>] ? btrfs_qgroup_account_extents+0x83/0x130 [btrfs] [14242.774558] [<ffffffffa0544c40>] btrfs_commit_transaction+0x590/0xb40 [btrfs] [14242.774599] [<ffffffffa0589b9d>] ? btrfs_log_dentry_safe+0x6d/0x80 [btrfs] [14242.774642] [<ffffffffa055ac54>] btrfs_sync_file+0x294/0x350 [btrfs] [14242.774650] [<ffffffff8123e29b>] vfs_fsync_range+0x3b/0xa0 [14242.774657] [<ffffffff81023891>] ? syscall_trace_enter_phase1+0x131/0x180 [14242.774663] [<ffffffff8123e35d>] do_fsync+0x3d/0x70 [14242.774669] [<ffffffff81023bb8>] ? syscall_trace_leave+0xb8/0x110 [14242.774675] [<ffffffff8123e600>] SyS_fsync+0x10/0x20 [14242.774681] [<ffffffff8175de6e>] entry_SYSCALL_64_fastpath+0x12/0x71 Fix this by never recursing into the finalization phase of block group creation and making sure we never trigger the finalization of block group creation while running delayed references. Reported-by: Josef Bacik <jbacik@fb.com> Fixes: 00d80e342c0f ("Btrfs: fix quick exhaustion of the system array in the superblock") Signed-off-by: Filipe Manana <fdmanana@suse.com>
2015-10-05Btrfs: update fix for read corruption of compressed and shared extentsFilipe Manana
My previous fix in commit 005efedf2c7d ("Btrfs: fix read corruption of compressed and shared extents") was effective only if the compressed extents cover a file range with a length that is not a multiple of 16 pages. That's because the detection of when we reached a different range of the file that shares the same compressed extent as the previously processed range was done at extent_io.c:__do_contiguous_readpages(), which covers subranges with a length up to 16 pages, because extent_readpages() groups the pages in clusters no larger than 16 pages. So fix this by tracking the start of the previously processed file range's extent map at extent_readpages(). The following test case for fstests reproduces the issue: seq=`basename $0` seqres=$RESULT_DIR/$seq echo "QA output created by $seq" tmp=/tmp/$$ status=1 # failure is the default! trap "_cleanup; exit \$status" 0 1 2 3 15 _cleanup() { rm -f $tmp.* } # get standard environment, filters and checks . ./common/rc . ./common/filter # real QA test starts here _need_to_be_root _supported_fs btrfs _supported_os Linux _require_scratch _require_cloner rm -f $seqres.full test_clone_and_read_compressed_extent() { local mount_opts=$1 _scratch_mkfs >>$seqres.full 2>&1 _scratch_mount $mount_opts # Create our test file with a single extent of 64Kb that is going to # be compressed no matter which compression algo is used (zlib/lzo). $XFS_IO_PROG -f -c "pwrite -S 0xaa 0K 64K" \ $SCRATCH_MNT/foo | _filter_xfs_io # Now clone the compressed extent into an adjacent file offset. $CLONER_PROG -s 0 -d $((64 * 1024)) -l $((64 * 1024)) \ $SCRATCH_MNT/foo $SCRATCH_MNT/foo echo "File digest before unmount:" md5sum $SCRATCH_MNT/foo | _filter_scratch # Remount the fs or clear the page cache to trigger the bug in # btrfs. Because the extent has an uncompressed length that is a # multiple of 16 pages, all the pages belonging to the second range # of the file (64K to 128K), which points to the same extent as the # first range (0K to 64K), had their contents full of zeroes instead # of the byte 0xaa. This was a bug exclusively in the read path of # compressed extents, the correct data was stored on disk, btrfs # just failed to fill in the pages correctly. _scratch_remount echo "File digest after remount:" # Must match the digest we got before. md5sum $SCRATCH_MNT/foo | _filter_scratch } echo -e "\nTesting with zlib compression..." test_clone_and_read_compressed_extent "-o compress=zlib" _scratch_unmount echo -e "\nTesting with lzo compression..." test_clone_and_read_compressed_extent "-o compress=lzo" status=0 exit Cc: stable@vger.kernel.org Signed-off-by: Filipe Manana <fdmanana@suse.com> Tested-by: Timofey Titovets <nefelim4ag@gmail.com>
2015-10-05Btrfs: send, fix corner case for reference overwrite detectionFilipe Manana
When the inode given to did_overwrite_ref() matches the current progress and has a reference that collides with the reference of other inode that has the same number as the current progress, we were always telling our caller that the inode's reference was overwritten, which is incorrect because the other inode might be a new inode (different generation number) in which case we must return false from did_overwrite_ref() so that its callers don't use an orphanized path for the inode (as it will never be orphanized, instead it will be unlinked and the new inode created later). The following test case for fstests reproduces the issue: seq=`basename $0` seqres=$RESULT_DIR/$seq echo "QA output created by $seq" tmp=/tmp/$$ status=1 # failure is the default! trap "_cleanup; exit \$status" 0 1 2 3 15 _cleanup() { rm -fr $send_files_dir rm -f $tmp.* } # get standard environment, filters and checks . ./common/rc . ./common/filter # real QA test starts here _supported_fs btrfs _supported_os Linux _require_scratch _need_to_be_root send_files_dir=$TEST_DIR/btrfs-test-$seq rm -f $seqres.full rm -fr $send_files_dir mkdir $send_files_dir _scratch_mkfs >>$seqres.full 2>&1 _scratch_mount # Create our test file with a single extent of 64K. mkdir -p $SCRATCH_MNT/foo $XFS_IO_PROG -f -c "pwrite -S 0xaa 0 64K" $SCRATCH_MNT/foo/bar \ | _filter_xfs_io _run_btrfs_util_prog subvolume snapshot -r $SCRATCH_MNT \ $SCRATCH_MNT/mysnap1 _run_btrfs_util_prog subvolume snapshot $SCRATCH_MNT \ $SCRATCH_MNT/mysnap2 echo "File digest before being replaced:" md5sum $SCRATCH_MNT/mysnap1/foo/bar | _filter_scratch # Remove the file and then create a new one in the same location with # the same name but with different content. This new file ends up # getting the same inode number as the previous one, because that inode # number was the highest inode number used by the snapshot's root and # therefore when attempting to find the a new inode number for the new # file, we end up reusing the same inode number. This happens because # currently btrfs uses the highest inode number summed by 1 for the # first inode created once a snapshot's root is loaded (done at # fs/btrfs/inode-map.c:btrfs_find_free_objectid in the linux kernel # tree). # Having these two different files in the snapshots with the same inode # number (but different generation numbers) caused the btrfs send code # to emit an incorrect path for the file when issuing an unlink # operation because it failed to realize they were different files. rm -f $SCRATCH_MNT/mysnap2/foo/bar $XFS_IO_PROG -f -c "pwrite -S 0xbb 0 96K" \ $SCRATCH_MNT/mysnap2/foo/bar | _filter_xfs_io _run_btrfs_util_prog subvolume snapshot -r $SCRATCH_MNT/mysnap2 \ $SCRATCH_MNT/mysnap2_ro _run_btrfs_util_prog send $SCRATCH_MNT/mysnap1 -f $send_files_dir/1.snap _run_btrfs_util_prog send -p $SCRATCH_MNT/mysnap1 \ $SCRATCH_MNT/mysnap2_ro -f $send_files_dir/2.snap echo "File digest in the original filesystem after being replaced:" md5sum $SCRATCH_MNT/mysnap2_ro/foo/bar | _filter_scratch # Now recreate the filesystem by receiving both send streams and verify # we get the same file contents that the original filesystem had. _scratch_unmount _scratch_mkfs >>$seqres.full 2>&1 _scratch_mount _run_btrfs_util_prog receive -vv $SCRATCH_MNT -f $send_files_dir/1.snap _run_btrfs_util_prog receive -vv $SCRATCH_MNT -f $send_files_dir/2.snap echo "File digest in the new filesystem:" # Must match the digest from the new file. md5sum $SCRATCH_MNT/mysnap2_ro/foo/bar | _filter_scratch status=0 exit Reported-by: Martin Raiber <martin@urbackup.org> Fixes: 8b191a684968 ("Btrfs: incremental send, check if orphanized dir inode needs delayed rename") Signed-off-by: Filipe Manana <fdmanana@suse.com>
2015-10-01Btrfs: move kobj stuff out of dev_replace lock rangeLiu Bo
To avoid deadlock described in commit 084b6e7c7607 ("btrfs: Fix a lockdep warning when running xfstest."), we should move kobj stuff out of dev_replace lock range. "It is because the btrfs_kobj_{add/rm}_device() will call memory allocation with GFP_KERNEL, which may flush fs page cache to free space, waiting for it self to do the commit, causing the deadlock. To solve the problem, move btrfs_kobj_{add/rm}_device() out of the dev_replace lock range, also involing split the btrfs_rm_dev_replace_srcdev() function into remove and free parts. Now only btrfs_rm_dev_replace_remove_srcdev() is called in dev_replace lock range, and kobj_{add/rm} and btrfs_rm_dev_replace_free_srcdev() are called out of the lock range." Signed-off-by: Liu Bo <bo.li.liu@oracle.com> Signed-off-by: Anand Jain <anand.jain@oracle.com> [added lockup description] Signed-off-by: David Sterba <dsterba@suse.com>
2015-10-01Btrfs: add helper for closing one deviceAnand Jain
Signed-off-by: Anand Jain <anand.jain@oracle.com> [reworded subject and changelog] Signed-off-by: David Sterba <dsterba@suse.com>
2015-10-01Btrfs: don't log error from btrfs_get_bdev_and_sbAnand Jain
Originally the message was not in a helper but ended up there. We should print error messages from callers instead. Signed-off-by: Anand Jain <anand.jain@oracle.com> [reworded subject and changelog] Signed-off-by: David Sterba <dsterba@suse.com>
2015-10-01Btrfs: kernel operation should come after user input has been verifiedAnand Jain
By general rule of thumb there shouldn't be any way that user land could trigger a kernel operation just by sending wrong arguments. Here do commit cleanups after user input has been verified. Signed-off-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
2015-10-01Btrfs: enhance btrfs_scratch_superblock to scratch all superblocksAnand Jain
This patch updates and renames btrfs_scratch_superblocks, (which is used by the replace device thread), with those fixes from the scratch superblock code section of btrfs_rm_device(). The fixes are: Scratch all copies of superblock Notify kobject that superblock has been changed Update time on the device So that btrfs_rm_device() can use the function btrfs_scratch_superblocks() instead of its own scratch code. And further replace deivce code which similarly releases device back to the system, will have the fixes from the btrfs device delete. Signed-off-by: Anand Jain <anand.jain@oracle.com> [renamed to btrfs_scratch_superblock] Signed-off-by: David Sterba <dsterba@suse.com>
2015-10-01Btrfs: add btrfs_read_dev_one_super() to read one specific SBAnand Jain
This uses a chunk of code from btrfs_read_dev_super() and creates a function called btrfs_read_dev_one_super() so that next patch can use it for scratch superblock. Signed-off-by: Anand Jain <anand.jain@oracle.com> [renamed bufhead to bh] Signed-off-by: David Sterba <dsterba@suse.com>
2015-10-01Btrfs: use BTRFS_ERROR_DEV_MISSING_NOT_FOUND when missing device is not foundAnand Jain
Use btrfs specific error code BTRFS_ERROR_DEV_MISSING_NOT_FOUND instead of -ENOENT. Next this removes the logging when user specifies "missing" and we don't find it in the kernel device list. Logging are for system events not for user input errors. Signed-off-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
2015-09-29Btrfs: consolidate btrfs_error() to btrfs_std_error()Anand Jain
btrfs_error() and btrfs_std_error() does the same thing and calls _btrfs_std_error(), so consolidate them together. And the main motivation is that btrfs_error() is closely named with btrfs_err(), one handles error action the other is to log the error, so don't closely name them. Signed-off-by: Anand Jain <anand.jain@oracle.com> Suggested-by: David Sterba <dsterba@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
2015-09-29Btrfs: __btrfs_std_error() logic should be consistent w/out CONFIG_PRINTK ↵Anand Jain
defined error handling logic behaves differently with or without CONFIG_PRINTK defined, since there are two copies of the same function which a bit of different logic One, when CONFIG_PRINTK is defined, code is __btrfs_std_error(..) { :: save_error_info(fs_info); if (sb->s_flags & MS_BORN) btrfs_handle_error(fs_info); } and two when CONFIG_PRINTK is not defined, the code is __btrfs_std_error(..) { :: if (sb->s_flags & MS_BORN) { save_error_info(fs_info); btrfs_handle_error(fs_info); } } I doubt if this was intentional ? and appear to have caused since we maintain two copies of the same function and they got diverged with commits. Now to decide which logic is correct reviewed changes as below, 533574c6bc30cf526cc1c41bde050c854a945efb Commit added two copies of this function cf79ffb5b79e8a2b587fbf218809e691bb396c98 Commit made change to only one copy of the function and to the copy when CONFIG_PRINTK is defined. To fix this, instead of maintaining two copies of same function approach, maintain single function, and just put the extra portion of the code under CONFIG_PRINTK define. This patch just does that. And keeps code of with CONFIG_PRINTK defined. Signed-off-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
2015-09-29Btrfs: SB read failure should return EIO for __bread failureAnand Jain
This will return EIO when __bread() fails to read SB, instead of EINVAL. Signed-off-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>