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2013-05-06btrfs: make static code static & remove dead codeEric Sandeen
Big patch, but all it does is add statics to functions which are in fact static, then remove the associated dead-code fallout. removed functions: btrfs_iref_to_path() __btrfs_lookup_delayed_deletion_item() __btrfs_search_delayed_insertion_item() __btrfs_search_delayed_deletion_item() find_eb_for_page() btrfs_find_block_group() range_straddles_pages() extent_range_uptodate() btrfs_file_extent_length() btrfs_scrub_cancel_devid() btrfs_start_transaction_lflush() btrfs_print_tree() is left because it is used for debugging. btrfs_start_transaction_lflush() and btrfs_reada_detach() are left for symmetry. ulist.c functions are left, another patch will take care of those. Signed-off-by: Eric Sandeen <sandeen@redhat.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-05-06Btrfs: fix error handling in btrfs_ioctl_send()Tsutomu Itoh
fget() returns NULL if error. So, we should check NULL or not. Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-05-06Btrfs: remove unused variable in __process_changed_new_xattr()Tsutomu Itoh
Variable 'p' is not used any more. So, remove it. Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-05-06Btrfs: allow omitting stream header and end-cmd for btrfs sendStefan Behrens
Two new flags are added to allow omitting the stream header and the end command for btrfs send streams. This is used in cases where you send multiple snapshots back-to-back in one stream. This used to be encoded like this (with 2 snapshots in this example): <stream header> + <sequence of commands> + <end cmd> + <stream header> + <sequence of commands> + <end cmd> + EOF The new format (if the two new flags are used) is this one: <stream header> + <sequence of commands> + <sequence of commands> + <end cmd> Note that the currently existing receivers treat <end cmd> only as an indication that a new <stream header> is following. This means, you can just skip the sequence <end cmd> <stream header> without loosing compatibility. As long as an EOF is following, the currently existing receivers handle the new format (if the two new flags are used) exactly as the old one. So what is the benefit of this change? The goal is to be able to use a single stream (one TCP connection) to multiplex a request/response handshake plus Btrfs send streams, all in the same stream. In this case you cannot evaluate an EOF condition as an end of the Btrfs send stream. You need something else, and the <end cmd> is just perfect for this purpose. The summary is: The format change is driven by the need to send several Btrfs send streams over a single TCP connections, with the ability for a repeated request/response handshake in the middle. And this format change does not break any existing tool, it is completely compatible. You could compare the old behaviour of the Btrfs send stream to the one of ftp where you need a seperate request/response channel and newly opened data transfer channels for each file, while the new behaviour is more like http using a single stream for everything. Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-03-29Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs Pull btrfs fixes from Chris Mason: "We've had a busy two weeks of bug fixing. The biggest patches in here are some long standing early-enospc problems (Josef) and a very old race where compression and mmap combine forces to lose writes (me). I'm fairly sure the mmap bug goes all the way back to the introduction of the compression code, which is proof that fsx doesn't trigger every possible mmap corner after all. I'm sure you'll notice one of these is from this morning, it's a small and isolated use-after-free fix in our scrub error reporting. I double checked it here." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: Btrfs: don't drop path when printing out tree errors in scrub Btrfs: fix wrong return value of btrfs_lookup_csum() Btrfs: fix wrong reservation of csums Btrfs: fix double free in the btrfs_qgroup_account_ref() Btrfs: limit the global reserve to 512mb Btrfs: hold the ordered operations mutex when waiting on ordered extents Btrfs: fix space accounting for unlink and rename Btrfs: fix space leak when we fail to reserve metadata space Btrfs: fix EIO from btrfs send in is_extent_unchanged for punched holes Btrfs: fix race between mmap writes and compression Btrfs: fix memory leak in btrfs_create_tree() Btrfs: fix locking on ROOT_REPLACE operations in tree mod log Btrfs: fix missing qgroup reservation before fallocating Btrfs: handle a bogus chunk tree nicely Btrfs: update to use fs_state bit
2013-03-28Btrfs: fix EIO from btrfs send in is_extent_unchanged for punched holesJan Schmidt
When you take a snapshot, punch a hole where there has been data, then take another snapshot and try to send an incremental stream, btrfs send would give you EIO. That is because is_extent_unchanged had no support for holes being punched. With this patch, instead of returning EIO we just return 0 (== the extent is not unchanged) and we're good. Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net> Cc: Alexander Block <ablock84@gmail.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-03-02Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs Pull btrfs update from Chris Mason: "The biggest feature in the pull is the new (and still experimental) raid56 code that David Woodhouse started long ago. I'm still working on the parity logging setup that will avoid inconsistent parity after a crash, so this is only for testing right now. But, I'd really like to get it out to a broader audience to hammer out any performance issues or other problems. scrub does not yet correct errors on raid5/6 either. Josef has another pass at fsync performance. The big change here is to combine waiting for metadata with waiting for data, which is a big latency win. It is also step one toward using atomics from the hardware during a commit. Mark Fasheh has a new way to use btrfs send/receive to send only the metadata changes. SUSE is using this to make snapper more efficient at finding changes between snapshosts. Snapshot-aware defrag is also included. Otherwise we have a large number of fixes and cleanups. Eric Sandeen wins the award for removing the most lines, and I'm hoping we steal this idea from XFS over and over again." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (118 commits) btrfs: fixup/remove module.h usage as required Btrfs: delete inline extents when we find them during logging btrfs: try harder to allocate raid56 stripe cache Btrfs: cleanup to make the function btrfs_delalloc_reserve_metadata more logic Btrfs: don't call btrfs_qgroup_free if just btrfs_qgroup_reserve fails Btrfs: remove reduplicate check about root in the function btrfs_clean_quota_tree Btrfs: return ENOMEM rather than use BUG_ON when btrfs_alloc_path fails Btrfs: fix missing deleted items in btrfs_clean_quota_tree btrfs: use only inline_pages from extent buffer Btrfs: fix wrong reserved space when deleting a snapshot/subvolume Btrfs: fix wrong reserved space in qgroup during snap/subv creation Btrfs: remove unnecessary dget_parent/dput when creating the pending snapshot btrfs: remove a printk from scan_one_device Btrfs: fix NULL pointer after aborting a transaction Btrfs: fix memory leak of log roots Btrfs: copy everything if we've created an inline extent btrfs: cleanup for open-coded alignment Btrfs: do not change inode flags in rename Btrfs: use reserved space for creating a snapshot clear chunk_alloc flag on retryable failure ...
2013-02-26Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs pile (part one) from Al Viro: "Assorted stuff - cleaning namei.c up a bit, fixing ->d_name/->d_parent locking violations, etc. The most visible changes here are death of FS_REVAL_DOT (replaced with "has ->d_weak_revalidate()") and a new helper getting from struct file to inode. Some bits of preparation to xattr method interface changes. Misc patches by various people sent this cycle *and* ocfs2 fixes from several cycles ago that should've been upstream right then. PS: the next vfs pile will be xattr stuff." * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (46 commits) saner proc_get_inode() calling conventions proc: avoid extra pde_put() in proc_fill_super() fs: change return values from -EACCES to -EPERM fs/exec.c: make bprm_mm_init() static ocfs2/dlm: use GFP_ATOMIC inside a spin_lock ocfs2: fix possible use-after-free with AIO ocfs2: Fix oops in ocfs2_fast_symlink_readpage() code path get_empty_filp()/alloc_file() leave both ->f_pos and ->f_version zero target: writev() on single-element vector is pointless export kernel_write(), convert open-coded instances fs: encode_fh: return FILEID_INVALID if invalid fid_type kill f_vfsmnt vfs: kill FS_REVAL_DOT by adding a d_weak_revalidate dentry op nfsd: handle vfs_getattr errors in acl protocol switch vfs_getattr() to struct path default SET_PERSONALITY() in linux/elf.h ceph: prepopulate inodes only when request is aborted d_hash_and_lookup(): export, switch open-coded instances 9p: switch v9fs_set_create_acl() to inode+fid, do it before d_instantiate() 9p: split dropping the acls from v9fs_set_create_acl() ...
2013-02-22new helper: file_inode(file)Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-20btrfs: add "no file data" flag to btrfs send ioctlMark Fasheh
This patch adds the flag, BTRFS_SEND_FLAG_NO_FILE_DATA to the btrfs send ioctl code. When this flag is set, the btrfs send code will never write file data into the stream (thus also avoiding expensive reads of that data in the first place). BTRFS_SEND_C_UPDATE_EXTENT commands will be sent (instead of BTRFS_SEND_C_WRITE) with an offset, length pair indicating the extent in question. This patch does not affect the operation of BTRFS_SEND_C_CLONE commands - they will continue to be sent when a search finds an appropriate extent to clone from. Signed-off-by: Mark Fasheh <mfasheh@suse.de> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-02-20btrfs: remove unused fd in btrfs_ioctl_send()Eric Sandeen
All we do is set it to NULL and test it :) Signed-off-by: Eric Sandeen <sandeen@redhat.com> Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-01-14Btrfs: fix memory leak in name_cache_insert()Tsutomu Itoh
We should free name_cache_entry before returning from the error handling code. Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
2012-12-16Btrfs: rename root_times_lock to root_item_lockAnand Jain
Originally root_times_lock was introduced as part of send/receive code however newly developed patch to label the subvol reused the same lock, so renaming it for a meaningful name. Signed-off-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-10-25Btrfs: Send: preserve ownership (uid and gid) also for symlinks.Alex Lyakas
This patch also requires a change in the user-space part of "receive". We need to use "lchown" instead of "chown". We will do this in the following patch. Signed-off-by: Alex Lyakas <alex.btrfs@zadarastorage.com> if (S_ISREG(sctx->cur_inode_mode)) {
2012-10-25Btrfs: send correct rdev and mode in btrfs-sendArne Jansen
When sending a device file, the stream was missing the mode. Also the rdev was encoded wrongly. Signed-off-by: Arne Jansen <sensille@gmx.net>
2012-10-25Btrfs: extended inode refs support for send mechanismJan Schmidt
This adds support for the new extended inode refs to btrfs send. Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2012-10-04Btrfs: write_buf is now callable outside send.cAnand Jain
Developing service cmds needs it. Signed-off-by: Anand Jain <anand.jain@oracle.com>
2012-10-01Btrfs: fix a bug in parsing return value in logical resolveLiu Bo
In logical resolve, we parse extent_from_logical()'s 'ret' as a kind of flag. It is possible to lose our errors because (-EXXXX & BTRFS_EXTENT_FLAG_TREE_BLOCK) is true. I'm not sure if it is on purpose, it just looks too hacky if it is. I'd rather use a real flag and a 'ret' to catch errors. Acked-by: Jan Schmidt <list.btrfs@jan-o-sch.net> Signed-off-by: Liu Bo <liub.liubo@gmail.com>
2012-10-01Btrfs: fix gcc warnings for 32bit compilesJan Schmidt
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net> Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-10-01Btrfs: fix btrfs send for inline items and compressionChris Mason
The btrfs send code was assuming the offset of the file item into the extent translated to bytes on disk. If we're compressed, this isn't true, and so it was off into extents owned by other files. It was also improperly handling inline extents. This solves a crash where we may have gone past the end of the file extent item by not testing early enough for an inline extent. It also solves problems where we have a whole between the end of the inline item and the start of the full extent. Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-10-01Btrfs: don't treat top/root directory inode as deleted/reusedAlexander Block
We can't do the deleted/reused logic for top/root inodes as it would create a stream that tries to delete and recreate the root dir. Reported-by: Alex Lyakas <alex.bolshoy.btrfs@gmail.com> Signed-off-by: Alexander Block <ablock84@googlemail.com>
2012-10-01Btrfs: ignore non-FS inodes for send/receiveAlexander Block
We have to ignore inode/space cache objects in send/receive. Reported-by: Alex Lyakas <alex.bolshoy.btrfs@gmail.com> Signed-off-by: Alexander Block <ablock84@googlemail.com>
2012-10-01Btrfs: pass root instead of parent_root to iterate_inode_refAlexander Block
We need to pass the root that we determined earlier to iterate_inode_ref. Reported-by: Alex Lyakas <alex.bolshoy.btrfs@gmail.com> Signed-off-by: Alexander Block <ablock84@googlemail.com>
2012-10-01Btrfs: use <= instead of < in is_extent_unchangedAlexander Block
Used the wrong compare operator here. Reported-by: Alex Lyakas <alex.bolshoy.btrfs@gmail.com> Signed-off-by: Alexander Block <ablock84@googlemail.com>
2012-10-01Btrfs: fix check for changed extent in is_extent_unchangedAlexander Block
The previous check was working fine, but this check should be easier to read. Also, we could theoritically have some exotic bugs with the previous checks. Signed-off-by: Alexander Block <ablock84@googlemail.com>
2012-10-01Btrfs: free nce and nce_head on error in name_cache_insertAlexander Block
Both were leaked in case of error. Reported-by: Alex Lyakas <alex.bolshoy.btrfs@gmail.com> Signed-off-by: Alexander Block <ablock84@googlemail.com>
2012-10-01Btrfs: remove unused tmp_path from iterate_dir_itemAlexander Block
A leftover from older code and unused now. Reported-by: Alex Lyakas <alex.bolshoy.btrfs@gmail.com> Signed-off-by: Alexander Block <ablock84@googlemail.com>
2012-10-01Btrfs: code cleanups for send/receiveAlexander Block
Doing some code cleanups as suggested by Arne. Changes do not change any logic. Signed-off-by: Alexander Block <ablock84@googlemail.com>
2012-10-01Btrfs: add/fix comments/documentation for send/receiveAlexander Block
As the subject already said, add/fix comments. Signed-off-by: Alexander Block <ablock84@googlemail.com>
2012-10-01Btrfs: update send_progress at correct placesAlexander Block
Updating send_progress in process_recorded_refs was not correct. It got updated too early in the cur_inode_new_gen case. Reported-by: Alex Lyakas <alex.bolshoy.btrfs@gmail.com> Reported-by: Arne Jansen <sensille@gmx.net> Signed-off-by: Alexander Block <ablock84@googlemail.com>
2012-10-01Btrfs: fix use of radix_tree for name_cache in send/receiveAlexander Block
We can't easily use the index of the radix tree for inums as the radix tree uses 32bit indexes on 32bit kernels. For 32bit kernels, we now use the lower 32bit of the inum as index and an additional list to store multiple entries per radix tree entry. Reported-by: Arne Jansen <sensille@gmx.net> Signed-off-by: Alexander Block <ablock84@googlemail.com>
2012-10-01Btrfs: fix memory leak for name_cache in send/receiveAlexander Block
When everything is done, name_cache_free is called which however forgot to call kfree on the cache entries. Signed-off-by: Alexander Block <ablock84@googlemail.com>
2012-10-01Btrfs: don't break in the final loop of find_extent_cloneAlexander Block
If we break, we may miss the clone from send_root which we prefer over all other clones. Commit is a result of Arne's review. Reported-by: Arne Jansen <sensille@gmx.net> Signed-off-by: Alexander Block <ablock84@googlemail.com>
2012-10-01Btrfs: use normal return path for root == send_root caseAlexander Block
Don't have a seperate return path for the mentioned case. Now we do the same "take lowest inode/offset" logic for all found clones. Commit is a result of Arne's review. Signed-off-by: Alexander Block <ablock84@googlemail.com>
2012-10-01Btrfs: use kmalloc instead of stack for backref_ctxAlexander Block
Make sure to never get in trouble due to the backref_ctx which was on the stack before. Commit is a result of Arne's review. Signed-off-by: Alexander Block <ablock84@googlemail.com>
2012-10-01Btrfs: rename backref_ctx::found_in_send_root to found_itselfAlexander Block
The new name should be easier to understand/read. Commit is a result of Arne's review. Signed-off-by: Alexander Block <ablock84@googlemail.com>
2012-10-01Btrfs: remove unused use_list from send/receive codeAlexander Block
use_list is a leftover and unused. Signed-off-by: Alexander Block <ablock84@googlemail.com>
2012-10-01Btrfs: add correct parent to check_dirs when dir got movedAlexander Block
We only added the parent for the new position of a moved dir. We also need to add the old parent of the moved dir. Reported-by: Alex Lyakas <alex.bolshoy.btrfs@gmail.com> Signed-off-by: Alexander Block <ablock84@googlemail.com>
2012-10-01Btrfs: remove unused code with #if 0Alexander Block
fs_path_remove is not used at the moment due to a previous patch. Remove it for now (with #if 0) to avoid compile warnings. Signed-off-by: Alexander Block <ablock84@googlemail.com>
2012-10-01Btrfs: add missing check for dir != tmp_dir to is_first_refAlexander Block
We missed that check which resultet in all refs with the same name being reported as first_ref. Reported-by: Alex Lyakas <alex.bolshoy.btrfs@gmail.com> Signed-off-by: Alexander Block <ablock84@googlemail.com>
2012-10-01Btrfs: fix cur_ino < parent_ino case for send/receiveAlexander Block
When the current inodes inum is smaller then the inum of the parent directory strange things were happending due to wrong path resolution and other bugs. Fix this with a new approach for the problem. Reported-by: Alex Lyakas <alex.bolshoy.btrfs@gmail.com> Signed-off-by: Alexander Block <ablock84@googlemail.com>
2012-10-01Btrfs: add rdev to get_inode_info in send/receiveAlexander Block
We need rdev in the next commit. Signed-off-by: Alexander Block <ablock84@googlemail.com>
2012-07-26Btrfs: using vmalloc and friends needs vmalloc.hStephen Rothwell
On powerpc, we don't get the implicit vmalloc.h include, and as a result the build fails noisily: fs/btrfs/send.c: In function 'fs_path_free': fs/btrfs/send.c:185:4: error: implicit declaration of function 'vfree' [-Werror=implicit-function-declaration] fs/btrfs/send.c: In function 'fs_path_ensure_buf': fs/btrfs/send.c:215:4: error: implicit declaration of function 'vmalloc' [-Werror=implicit-function-declaration] fs/btrfs/send.c:215:12: warning: assignment makes pointer from integer without a cast [enabled by default] fs/btrfs/send.c:225:12: warning: assignment makes pointer from integer without a cast [enabled by default] fs/btrfs/send.c:233:13: warning: assignment makes pointer from integer without a cast [enabled by default] fs/btrfs/send.c: In function 'iterate_dir_item': fs/btrfs/send.c:900:10: warning: assignment makes pointer from integer without a cast [enabled by default] fs/btrfs/send.c:909:11: warning: assignment makes pointer from integer without a cast [enabled by default] fs/btrfs/send.c: In function 'btrfs_ioctl_send': fs/btrfs/send.c:4463:17: warning: assignment makes pointer from integer without a cast [enabled by default] fs/btrfs/send.c:4469:17: warning: assignment makes pointer from integer without a cast [enabled by default] fs/btrfs/send.c:4475:2: error: implicit declaration of function 'vzalloc' [-Werror=implicit-function-declaration] fs/btrfs/send.c:4475:20: warning: assignment makes pointer from integer without a cast [enabled by default] fs/btrfs/send.c:4483:21: warning: assignment makes pointer from integer without a cast [enabled by default] Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-07-26Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs Pull large btrfs update from Chris Mason: "This pull request is very large, and the two main features in here have been under testing/devel for quite a while. We have subvolume quotas from the strato developers. This enables full tracking of how many blocks are allocated to each subvolume (and all snapshots) and you can set limits on a per-subvolume basis. You can also create quota groups and toss multiple subvolumes into a big group. It's everything you need to be a web hosting company and give each user their own subvolume. The userland side of the quotas is being refreshed, they'll send out details on where to grab it soon. Next is the kernel side of btrfs send/receive from Alexander Block. This leverages the same infrastructure as the quota code to figure out relationships between blocks and their owners. It can then compute the difference between two snapshots and sends the diffs in a neutral format into userland. The basic model: create a snapshot send that snapshot as the initial backup make changes create a second snapshot send the incremental as a backup delete the first snapshot (use the second snapshot for the next incremental) The receive portion is all in userland, and in the 'next' branch of my btrfs-progs repo. There's still some work to do in terms of optimizing the send side from kernel to userland. The really important part is figuring out how two snapshots are different, and this is where we are concentrating right now. The initial send of a dataset is a little slower than tar, but the incremental sends are dramatically faster than what rsync can do. On top of all of that, we have a nice queue of fixes, cleanups and optimizations." Fix up trivial modify/del conflict in fs/btrfs/ioctl.c Also fix up semantic conflict in fs/btrfs/send.c: the interface to dentry_open() changed in commit 765927b2d508 ("switch dentry_open() to struct path, make it grab references itself"), and since it now grabs whatever references it needs, we should no longer do the mntget() on the mnt (and we need to dput() the dentry reference we took). * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (65 commits) Btrfs: uninit variable fixes in send/receive Btrfs: introduce BTRFS_IOC_SEND for btrfs send/receive Btrfs: add btrfs_compare_trees function Btrfs: introduce subvol uuids and times Btrfs: make iref_to_path non static Btrfs: add a barrier before a waitqueue_active check Btrfs: call the ordered free operation without any locks held Btrfs: Check INCOMPAT flags on remount and add helper function Btrfs: add helper for tree enumeration btrfs: allow cross-subvolume file clone Btrfs: improve multi-thread buffer read Btrfs: make btrfs's allocation smoothly with preallocation Btrfs: lock the transition from dirty to writeback for an eb Btrfs: fix potential race in extent buffer freeing Btrfs: don't return true in releasepage unless we actually freed the eb Btrfs: suppress printk() if all device I/O stats are zero Btrfs: remove unwanted printk() for btrfs device I/O stats Btrfs: rewrite BTRFS_SETGET_FUNCS Btrfs: zero unused bytes in inode item Btrfs: kill free_space pointer from inode structure ... Conflicts: fs/btrfs/ioctl.c
2012-07-25Btrfs: uninit variable fixes in send/receiveChris Mason
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-07-25Btrfs: introduce BTRFS_IOC_SEND for btrfs send/receiveAlexander Block
This patch introduces the BTRFS_IOC_SEND ioctl that is required for send. It allows btrfs-progs to implement full and incremental sends. Patches for btrfs-progs will follow. Signed-off-by: Alexander Block <ablock84@googlemail.com> Reviewed-by: David Sterba <dave@jikos.cz> Reviewed-by: Arne Jansen <sensille@gmx.net> Reviewed-by: Jan Schmidt <list.btrfs@jan-o-sch.net> Reviewed-by: Alex Lyakas <alex.bolshoy.btrfs@gmail.com>