linux.git/fs/btrfs, branch master

Merge branch 'for-linus-4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs

2017-02-11T17:15:58+00:00

Pull btrfs fixes from Chris Mason: "This has two last minute fixes. The highest priority here is a regression fix for the decompression code, but we also fixed up a problem with the 32-bit compat ioctls. The decompression bug could hand back the wrong data on big reads when zlib was used. I have a larger cleanup to make the math here less error prone, but at this stage in the release Omar's patch is the best choice" * 'for-linus-4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: btrfs: fix btrfs_decompress_buf2page() btrfs: fix btrfs_compat_ioctl failures on non-compat ioctls

Btrfs: fix btrfs_decompress_buf2page()

2017-02-11T03:11:03+00:00

If btrfs_decompress_buf2page() is handed a bio with its page in the middle of the working buffer, then we adjust the offset into the working buffer. After we copy into the bio, we advance the iterator by the number of bytes we copied. Then, we have some logic to handle the case of discontiguous pages and adjust the offset into the working buffer again. However, if we didn't advance the bio to a new page, we may enter this case in error, essentially repeating the adjustment that we already made when we entered the function. The end result is bogus data in the bio. Previously, we only checked for this case when we advanced to a new page, but the conversion to bio iterators changed that. This restores the old, correct behavior. A case I saw when testing with zlib was: buf_start = 42769 total_out = 46865 working_bytes = total_out - buf_start = 4096 start_byte = 45056 The condition (total_out > start_byte && buf_start < start_byte) is true, so we adjust the offset: buf_offset = start_byte - buf_start = 2287 working_bytes -= buf_offset = 1809 current_buf_start = buf_start = 42769 Then, we copy bytes = min(bvec.bv_len, PAGE_SIZE - buf_offset, working_bytes) = 1809 buf_offset += bytes = 4096 working_bytes -= bytes = 0 current_buf_start += bytes = 44578 After bio_advance(), we are still in the same page, so start_byte is the same. Then, we check (total_out > start_byte && current_buf_start < start_byte), which is true! So, we adjust the values again: buf_offset = start_byte - buf_start = 2287 working_bytes = total_out - start_byte = 1809 current_buf_start = buf_start + buf_offset = 45056 But note that working_bytes was already zero before this, so we should have stopped copying. Fixes: 974b1adc3b10 ("btrfs: use bio iterators for the decompression handlers") Reported-by: Pat Erley Reviewed-by: Chris Mason Signed-off-by: Omar Sandoval Signed-off-by: Chris Mason Reviewed-by: Liu Bo Tested-by: Liu Bo

btrfs: fix btrfs_compat_ioctl failures on non-compat ioctls

2017-02-08T16:47:30+00:00

Commit 4c63c2454ef incorrectly assumed that returning -ENOIOCTLCMD would cause the native ioctl to be called. The ->compat_ioctl callback is expected to handle all ioctls, not just compat variants. As a result, when using 32-bit userspace on 64-bit kernels, everything except those three ioctls would return -ENOTTY. Fixes: 4c63c2454ef ("btrfs: bugfix: handle FS_IOC32_{GETFLAGS,SETFLAGS,GETVERSION} in btrfs_ioctl") Cc: stable@vger.kernel.org Signed-off-by: Jeff Mahoney Reviewed-by: David Sterba Signed-off-by: David Sterba

Merge branch 'for-linus-4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs

2017-01-27T20:41:46+00:00

Pull btrfs updates from Chris Mason: "Some fixes that we've collected from the list. We still have one more pending to nail down a regression in lzo compression, but I wanted to get this batch out the door" * 'for-linus-4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: Btrfs: remove ->{get, set}_acl() from btrfs_dir_ro_inode_operations Btrfs: disable xattr operations on subvolume directories Btrfs: remove old tree_root case in btrfs_read_locked_inode() Btrfs: fix truncate down when no_holes feature is enabled Btrfs: Fix deadlock between direct IO and fast fsync btrfs: fix false enospc error when truncating heavily reflinked file

Btrfs: remove ->{get, set}_acl() from btrfs_dir_ro_inode_operations

2017-01-26T23:48:56+00:00

Subvolume directory inodes can't have ACLs. Cc: # 4.9.x Signed-off-by: Omar Sandoval Reviewed-by: David Sterba Signed-off-by: Chris Mason

Btrfs: disable xattr operations on subvolume directories

2017-01-26T23:48:55+00:00

When you snapshot a subvolume containing a subvolume, you get a placeholder directory where the subvolume would be. These directory inodes have ->i_ops set to btrfs_dir_ro_inode_operations. Previously, these i_ops didn't include the xattr operation callbacks. The conversion to xattr_handlers missed this case, leading to bogus attempts to set xattrs on these inodes. This manifested itself as failures when running delayed inodes. To fix this, clear IOP_XATTR in ->i_opflags on these inodes. Fixes: 6c6ef9f26e59 ("xattr: Stop calling {get,set,remove}xattr inode operations") Cc: Andreas Gruenbacher Reported-by: Chris Murphy Tested-by: Chris Murphy Cc: # 4.9.x Signed-off-by: Omar Sandoval Reviewed-by: David Sterba Signed-off-by: Chris Mason

Btrfs: remove old tree_root case in btrfs_read_locked_inode()

2017-01-26T23:48:55+00:00

As Jeff explained in c2951f32d36c ("btrfs: remove old tree_root dirent processing in btrfs_real_readdir()"), supporting this old format is no longer necessary since the Btrfs magic number has been updated since we changed to the current format. There are other places where we still handle this old format, but since this is part of a fix that is going to stable, I'm only removing this one for now. Cc: # 4.9.x Signed-off-by: Omar Sandoval Reviewed-by: David Sterba Signed-off-by: Chris Mason

Btrfs: fix truncate down when no_holes feature is enabled

2017-01-19T17:02:22+00:00

For such a file mapping, [0-4k][hole][8k-12k] In NO_HOLES mode, we don't have the [hole] extent any more. Commit c1aa45759e90 ("Btrfs: fix shrinking truncate when the no_holes feature is enabled") fixed disk isize not being updated in NO_HOLES mode when data is not flushed. However, even if data has been flushed, we can still have trouble in updating disk isize since we updated disk isize to 'start' of the last evicted extent. Reviewed-by: Chris Mason Signed-off-by: Liu Bo Signed-off-by: David Sterba

Btrfs: Fix deadlock between direct IO and fast fsync

2017-01-19T17:01:02+00:00

The following deadlock is seen when executing generic/113 test, ---------------------------------------------------------+---------------------------------------------------- Direct I/O task Fast fsync task ---------------------------------------------------------+---------------------------------------------------- btrfs_direct_IO __blockdev_direct_IO do_blockdev_direct_IO do_direct_IO btrfs_get_blocks_direct while (blocks needs to written) get_more_blocks (first iteration) btrfs_get_blocks_direct btrfs_create_dio_extent down_read(&BTRFS_I(inode) >dio_sem) Create and add extent map and ordered extent up_read(&BTRFS_I(inode) >dio_sem) btrfs_sync_file btrfs_log_dentry_safe btrfs_log_inode_parent btrfs_log_inode btrfs_log_changed_extents down_write(&BTRFS_I(inode) >dio_sem) Collect new extent maps and ordered extents wait for ordered extent completion get_more_blocks (second iteration) btrfs_get_blocks_direct btrfs_create_dio_extent down_read(&BTRFS_I(inode) >dio_sem) -------------------------------------------------------------------------------------------------------------- In the above description, Btrfs direct I/O code path has not yet started submitting bios for file range covered by the initial ordered extent. Meanwhile, The fast fsync task obtains the write semaphore and waits for I/O on the ordered extent to get completed. However, the Direct I/O task is now blocked on obtaining the read semaphore. To resolve the deadlock, this commit modifies the Direct I/O code path to obtain the read semaphore before invoking __blockdev_direct_IO(). The semaphore is then given up after __blockdev_direct_IO() returns. This allows the Direct I/O code to complete I/O on all the ordered extents it creates. Signed-off-by: Chandan Rajendra Reviewed-by: Filipe Manana Signed-off-by: David Sterba

btrfs: fix false enospc error when truncating heavily reflinked file

2017-01-19T17:00:58+00:00

Below test script can reveal this bug: dd if=/dev/zero of=fs.img bs=$((1024*1024)) count=100 dev=$(losetup --show -f fs.img) mkdir -p /mnt/mntpoint mkfs.btrfs -f $dev mount $dev /mnt/mntpoint cd /mnt/mntpoint echo "workdir is: /mnt/mntpoint" blocksize=$((128 * 1024)) dd if=/dev/zero of=testfile bs=$blocksize count=1 sync count=$((17*1024*1024*1024/blocksize)) echo "file size is:" $((count*blocksize)) for ((i = 1; i <= $count; i++)); do dst_offset=$((blocksize * i)) xfs_io -f -c "reflink testfile 0 $dst_offset $blocksize"\ testfile > /dev/null done sync truncate --size 0 testfile The last truncate operation will fail for ENOSPC reason, but indeed it should not fail. In btrfs_truncate(), we use a temporary block_rsv to do truncate operation. With every btrfs_truncate_inode_items() call, we migrate space to this block_rsv, but forget to cleanup previous reservation, which will make this block_rsv's reserved bytes keep growing, and this reserved space will only be released in the end of btrfs_truncate(), this metadata leak will impact other's metadata reservation. In this case, it's "btrfs_start_transaction(root, 2);" fails for enospc error, which make this truncate operation fail. Call btrfs_block_rsv_release() to fix this bug. Signed-off-by: Wang Xiaoguang Reviewed-by: David Sterba Signed-off-by: David Sterba