Commit Graph

245 Commits

Author SHA1 Message Date
Filipe Manana b786f16ac3 Btrfs: send, fix corner case for reference overwrite detection
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: 8b191a6849 ("Btrfs: incremental send, check if orphanized dir inode needs delayed rename")
Signed-off-by: Filipe Manana <fdmanana@suse.com>
2015-10-05 16:56:27 -07:00
Josef Bacik 37b8d27de5 Btrfs: use received_uuid of parent during send
Neil Horman pointed out a problem where if he did something like this

receive A
snap A B
change B
send -p A B

and then on another box do

recieve A
receive B

the receive B would fail because we use the UUID of A for the clone sources for
B.  This makes sense most of the time because normally you are sending from the
original sources, not a received source.  However when you use a recieved subvol
its UUID is going to be something completely different, so if you then try to
receive the diff on a different volume it won't find the UUID because the new A
will be something else.  The only constant is the received uuid.  So instead
check to see if we have received_uuid set on the root, and if so use that as the
clone source, as btrfs receive looks for matches either in received_uuid or
uuid.  Thanks,

Reported-by: Neil Horman <nhorman@redhat.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: Hugo Mills <hugo@carfax.org.uk>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-12 13:20:38 -07:00
Chris Mason 1ab818b137 Merge branch 'send_fixes_4.2' of git://git.kernel.org/pub/scm/linux/kernel/git/fdmanana/linux into for-linus-4.2 2015-06-10 07:02:41 -07:00
Filipe Manana 619d8c4ef7 Btrfs: incremental send, fix clone operations for compressed extents
Marc reported a problem where the receiving end of an incremental send
was performing clone operations that failed with -EINVAL. This happened
because, unlike for uncompressed extents, we were not checking if the
source clone offset and length, after summing the data offset, falls
within the source file's boundaries.

So make sure we do such checks when attempting to issue clone operations
for compressed extents.

Problem reproducible with the following steps:

  $ mkfs.btrfs -f /dev/sdb
  $ mount -o compress /dev/sdb /mnt
  $ mkfs.btrfs -f /dev/sdc
  $ mount -o compress /dev/sdc /mnt2

  # Create the file with a single extent of 128K. This creates a metadata file
  # extent item with a data start offset of 0 and a logical length of 128K.
  $ xfs_io -f -c "pwrite -S 0xaa 64K 128K" -c "fsync" /mnt/foo

  # Now rewrite the range 64K to 112K of our file. This will make the inode's
  # metadata continue to point to the 128K extent we created before, but now
  # with an extent item that points to the extent with a data start offset of
  # 112K and a logical length of 16K.
  # That metadata file extent item is associated with the logical file offset
  # at 176K and covers the logical file range 176K to 192K.
  $ xfs_io -c "pwrite -S 0xbb 64K 112K" -c "fsync" /mnt/foo

  # Now rewrite the range 180K to 12K. This will make the inode's metadata
  # continue to point the the 128K extent we created earlier, with a single
  # extent item that points to it with a start offset of 112K and a logical
  # length of 4K.
  # That metadata file extent item is associated with the logical file offset
  # at 176K and covers the logical file range 176K to 180K.
  $ xfs_io -c "pwrite -S 0xcc 180K 12K" -c "fsync" /mnt/foo

  $ btrfs subvolume snapshot -r /mnt /mnt/snap1

  $ touch /mnt/bar
  # Calls the btrfs clone ioctl.
  $ ~/xfstests/src/cloner -s $((176 * 1024)) -d $((176 * 1024)) \
    -l $((4 * 1024)) /mnt/foo /mnt/bar

  $ btrfs subvolume snapshot -r /mnt /mnt/snap2

  $ btrfs send /mnt/snap1 | btrfs receive /mnt2
  At subvol /mnt/snap1
  At subvol snap1

  $ btrfs send -p /mnt/snap1 /mnt/snap2 | btrfs receive /mnt2
  At subvol /mnt/snap2
  At snapshot snap2
  ERROR: failed to clone extents to bar
  Invalid argument

A test case for fstests follows soon.

Reported-by: Marc MERLIN <marc@merlins.org>
Tested-by: Marc MERLIN <marc@merlins.org>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Tested-by: David Sterba <dsterba@suse.cz>
Tested-by: Jan Alexander Steffens (heftig) <jan.steffens@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-06-02 19:34:35 -07:00
Filipe Manana 8b191a6849 Btrfs: incremental send, check if orphanized dir inode needs delayed rename
If a directory inode is orphanized, because some inode previously
processed has a new name that collides with the old name of the current
inode, we need to check if it needs its rename operation delayed too,
as its ancestor-descendent relationship with some other inode might
have been reversed between the parent and send snapshots and therefore
its rename operation needs to happen after that other inode is renamed.

For example, for the following reproducer where this is needed (provided
by Robbie Ko):

  $ mkfs.btrfs -f /dev/sdb
  $ mount /dev/sdb /mnt
  $ mkfs.btrfs -f /dev/sdc
  $ mount /dev/sdc /mnt2

  $ mkdir -p /mnt/data/n1/n2
  $ mkdir /mnt/data/n4
  $ mkdir -p /mnt/data/t6/t7
  $ mkdir /mnt/data/t5
  $ mkdir /mnt/data/t7
  $ mkdir /mnt/data/n4/t2
  $ mkdir /mnt/data/t4
  $ mkdir /mnt/data/t3
  $ mv /mnt/data/t7 /mnt/data/n4/t2
  $ mv /mnt/data/t4 /mnt/data/n4/t2/t7
  $ mv /mnt/data/t5 /mnt/data/n4/t2/t7/t4
  $ mv /mnt/data/t6 /mnt/data/n4/t2/t7/t4/t5
  $ mv /mnt/data/n1/n2 /mnt/data/n4/t2/t7/t4/t5/t6
  $ mv /mnt/data/n1 /mnt/data/n4/t2/t7/t4/t5/t6
  $ mv /mnt/data/n4/t2/t7/t4/t5/t6/t7 /mnt/data/n4/t2/t7/t4/t5/t6/n2
  $ mv /mnt/data/t3 /mnt/data/n4/t2/t7/t4/t5/t6/n2/t7

  $ btrfs subvolume snapshot -r /mnt /mnt/snap1

  $ mv /mnt/data/n4/t2/t7/t4/t5/t6/n1 /mnt/data/n4
  $ mv /mnt/data/n4/t2 /mnt/data/n4/n1
  $ mv /mnt/data/n4/n1/t2/t7/t4/t5/t6/n2 /mnt/data/n4/n1/t2
  $ mv /mnt/data/n4/n1/t2/n2/t7/t3 /mnt/data/n4/n1/t2
  $ mv /mnt/data/n4/n1/t2/t7/t4/t5/t6 /mnt/data/n4/n1/t2
  $ mv /mnt/data/n4/n1/t2/t7/t4 /mnt/data/n4/n1/t2/t6
  $ mv /mnt/data/n4/n1/t2/t7 /mnt/data/n4/n1/t2/t3
  $ mv /mnt/data/n4/n1/t2/n2/t7 /mnt/data/n4/n1/t2

  $ btrfs subvolume snapshot -r /mnt /mnt/snap2

  $ btrfs send /mnt/snap1 | btrfs receive /mnt2
  $ btrfs send -p /mnt/snap1 /mnt/snap2 | btrfs receive /mnt2
  ERROR: send ioctl failed with -12: Cannot allocate memory

Where the parent snapshot directory hierarchy is the following:

  .                                                        (ino 256)
  |-- data/                                                (ino 257)
        |-- n4/                                            (ino 260)
             |-- t2/                                       (ino 265)
                  |-- t7/                                  (ino 264)
                       |-- t4/                             (ino 266)
                            |-- t5/                        (ino 263)
                                 |-- t6/                   (ino 261)
                                      |-- n1/              (ino 258)
                                      |-- n2/              (ino 259)
                                           |-- t7/         (ino 262)
                                                |-- t3/    (ino 267)

And the send snapshot's directory hierarchy is the following:

  .                                                        (ino 256)
  |-- data/                                                (ino 257)
        |-- n4/                                            (ino 260)
             |-- n1/                                       (ino 258)
                  |-- t2/                                  (ino 265)
                       |-- n2/                             (ino 259)
                       |-- t3/                             (ino 267)
                       |    |-- t7                         (ino 264)
                       |
                       |-- t6/                             (ino 261)
                       |    |-- t4/                        (ino 266)
                       |         |-- t5/                   (ino 263)
                       |
                       |-- t7/                             (ino 262)

While processing inode 262 we orphanize inode 264 and later attempt
to rename inode 264 to its new name/location, which resulted in building
an incorrect destination path string for the rename operation with the
value "data/n4/t2/t7/t4/t5/t6/n2/t7/t3/t7". This rename operation must
have been done only after inode 267 is processed and renamed, as the
ancestor-descendent relationship between inodes 264 and 267 was reversed
between both snapshots, because otherwise it results in an infinite loop
when building the path string for inode 264 when we are processing an
inode with a number larger than 264. That loop is the following:

  start inode 264, send progress of 265 for example
  parent of 264 -> 267
  parent of 267 -> 262
  parent of 262 -> 259
  parent of 259 -> 261
  parent of 261 -> 263
  parent of 263 -> 266
  parent of 266 -> 264
    |--> back to first iteration while current path string length
         is <= PATH_MAX, and fail with -ENOMEM otherwise

So fix this by making the check if we need to delay a directory rename
regardless of the current inode having been orphanized or not.

A test case for fstests follows soon.

Thanks to Robbie Ko for providing a reproducer for this problem.

Reported-by: Robbie Ko <robbieko@synology.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
2015-06-03 03:10:40 +01:00
Filipe Manana 80aa602756 Btrfs: incremental send, don't delay directory renames unnecessarily
Even though we delay the rename of directories when they become
descendents of other directories that were also renamed in the send
root to prevent infinite path build loops, we were doing it in cases
where this was not needed and was actually harmful resulting in
infinite path build loops as we ended up with a circular dependency
of delayed directory renames.

Consider the following reproducer:

  $ mkfs.btrfs -f /dev/sdb
  $ mount /dev/sdb /mnt
  $ mkfs.btrfs -f /dev/sdc
  $ mount /dev/sdc /mnt2

  $ mkdir /mnt/data
  $ mkdir /mnt/data/n1
  $ mkdir /mnt/data/n1/n2
  $ mkdir /mnt/data/n4
  $ mkdir /mnt/data/n1/n2/p1
  $ mkdir /mnt/data/n1/n2/p1/p2
  $ mkdir /mnt/data/t6
  $ mkdir /mnt/data/t7
  $ mkdir -p /mnt/data/t5/t7
  $ mkdir /mnt/data/t2
  $ mkdir /mnt/data/t4
  $ mkdir -p /mnt/data/t1/t3
  $ mkdir /mnt/data/p1
  $ mv /mnt/data/t1 /mnt/data/p1
  $ mkdir -p /mnt/data/p1/p2
  $ mv /mnt/data/t4 /mnt/data/p1/p2/t1
  $ mv /mnt/data/t5 /mnt/data/n4/t5
  $ mv /mnt/data/n1/n2/p1/p2 /mnt/data/n4/t5/p2
  $ mv /mnt/data/t7 /mnt/data/n4/t5/p2/t7
  $ mv /mnt/data/t2 /mnt/data/n4/t1
  $ mv /mnt/data/p1 /mnt/data/n4/t5/p2/p1
  $ mv /mnt/data/n1/n2 /mnt/data/n4/t5/p2/p1/p2/n2
  $ mv /mnt/data/n4/t5/p2/p1/p2/t1 /mnt/data/n4/t5/p2/p1/p2/n2/t1
  $ mv /mnt/data/n4/t5/t7 /mnt/data/n4/t5/p2/p1/p2/n2/t1/t7
  $ mv /mnt/data/n4/t5/p2/p1/t1/t3 /mnt/data/n4/t5/p2/p1/p2/n2/t1/t3
  $ mv /mnt/data/n4/t5/p2/p1/p2/n2/p1 /mnt/data/n4/t5/p2/p1/p2/n2/t1/t7/p1
  $ mv /mnt/data/t6 /mnt/data/n4/t5/p2/p1/p2/n2/t1/t3/t5
  $ mv /mnt/data/n4/t5/p2/p1/t1 /mnt/data/n4/t5/p2/p1/p2/n2/t1/t3/t1
  $ mv /mnt/data/n1 /mnt/data/n4/t5/p2/p1/p2/n2/t1/t7/p1/n1

  $ btrfs subvolume snapshot -r /mnt /mnt/snap1

  $ mv /mnt/data/n4/t1 /mnt/data/n4/t5/p2/p1/p2/n2/t1/t7/p1/t1
  $ mv /mnt/data/n4/t5/p2/p1/p2/n2/t1 /mnt/data/n4/
  $ mv /mnt/data/n4/t5/p2/p1/p2/n2 /mnt/data/n4/t1/n2
  $ mv /mnt/data/n4/t1/t7/p1 /mnt/data/n4/t1/n2/p1
  $ mv /mnt/data/n4/t1/t3/t1 /mnt/data/n4/t1/n2/t1
  $ mv /mnt/data/n4/t1/t3 /mnt/data/n4/t1/n2/t1/t3
  $ mv /mnt/data/n4/t5/p2/p1/p2 /mnt/data/n4/t1/n2/p1/p2
  $ mv /mnt/data/n4/t1/t7 /mnt/data/n4/t1/n2/p1/t7
  $ mv /mnt/data/n4/t5/p2/p1 /mnt/data/n4/t1/n2/p1/p2/p1
  $ mv /mnt/data/n4/t1/n2/t1/t3/t5 /mnt/data/n4/t1/n2/p1/p2/t5
  $ mv /mnt/data/n4/t5 /mnt/data/n4/t1/n2/p1/p2/p1/t5
  $ mv /mnt/data/n4/t1/n2/p1/p2/p1/t5/p2 /mnt/data/n4/t1/n2/p1/p2/p1/p2
  $ mv /mnt/data/n4/t1/n2/p1/p2/p1/p2/t7 /mnt/data/n4/t1/t7

  $ btrfs subvolume snapshot -r /mnt /mnt/snap2

  $ btrfs send /mnt/snap1 | btrfs receive /mnt2
  $ btrfs send -p /mnt/snap1 /mnt/snap2 | btrfs receive -vv /mnt2
  ERROR: send ioctl failed with -12: Cannot allocate memory

This reproducer resulted in an infinite path build loop when building the
path for inode 266 because the following circular dependency of delayed
directory renames was created:

   ino 272 <- ino 261 <- ino 259 <- ino 268 <- ino 267 <- ino 261

Where the notation "X <- Y" means the rename of inode X is delayed by the
rename of inode Y (X will be renamed after Y is renamed). This resulted
in an infinite path build loop of inode 266 because that inode has inode
261 as an ancestor in the send root and inode 261 is in the circular
dependency of delayed renames listed above.

Fix this by not delaying the rename of a directory inode if an ancestor of
the inode in the send root, which has a delayed rename operation, is not
also a descendent of the inode in the parent root.

Thanks to Robbie Ko for sending the reproducer example.
A test case for xfstests follows soon.

Reported-by: Robbie Ko <robbieko@synology.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
2015-06-03 03:10:20 +01:00
Filipe Manana 5f806c3ae2 Btrfs: incremental send, remove dead code
The logic to detect path loops when attempting to apply a pending
directory rename, introduced in commit
f959492fc1 (Btrfs: send, fix more issues related to directory renames)
is no longer needed, and the respective fstests test case for that commit,
btrfs/045, now passes without this code (as well as all the other test
cases for send/receive).

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-03-26 17:55:52 -07:00
Filipe Manana 8996a48c0a Btrfs: incremental send, clear name from cache after orphanization
If a directory's reference ends up being orphanized, because the inode
currently being processed has a new path that matches that directory's
path, make sure we evict the name of the directory from the name cache.
This is because there might be descendent inodes (either directories or
regular files) that will be orphanized later too, and therefore the
orphan name of the ancestor must be used, otherwise we send issue rename
operations with a wrong path in the send stream.

Reproducer:

  $ mkfs.btrfs -f /dev/sdb
  $ mount /dev/sdb /mnt

  $ mkdir -p /mnt/data/n1/n2/p1/p2
  $ mkdir /mnt/data/n4
  $ mkdir -p /mnt/data/p1/p2

  $ btrfs subvolume snapshot -r /mnt /mnt/snap1

  $ mv /mnt/data/p1/p2 /mnt/data
  $ mv /mnt/data/n1/n2/p1/p2 /mnt/data/p1
  $ mv /mnt/data/p2 /mnt/data/n1/n2/p1
  $ mv /mnt/data/n1/n2 /mnt/data/p1
  $ mv /mnt/data/p1 /mnt/data/n4
  $ mv /mnt/data/n4/p1/n2/p1 /mnt/data

  $ btrfs subvolume snapshot -r /mnt /mnt/snap2

  $ btrfs send /mnt/snap1 -f /tmp/1.send
  $ btrfs send -p /mnt/snap1 /mnt/snap2 -f /tmp/2.send

  $ mkfs.btrfs -f /dev/sdc
  $ mount /dev/sdc /mnt2
  $ btrfs receive /mnt2 -f /tmp/1.send
  $ btrfs receive /mnt2 -f /tmp/2.send
  ERROR: rename data/p1/p2 -> data/n4/p1/p2 failed. no such file or directory

Directories data/p1 (inode 263) and data/p1/p2 (inode 264) in the parent
snapshot are both orphanized during the incremental send, and as soon as
data/p1 is orphanized, we must make sure that when orphanizing data/p1/p2
we use a source path of o263-6-o/p2 for the rename operation instead of
the old path data/p1/p2 (the one before the orphanization of inode 263).

A test case for xfstests follows soon.

Reported-by: Robbie Ko <robbieko@synology.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-03-26 17:55:51 -07:00
Filipe Manana 2f1f465ae6 Btrfs: send, don't leave without decrementing clone root's send_progress
If the clone root was not readonly or the dead flag was set on it, we were
leaving without decrementing the root's send_progress counter (and before
we just incremented it). If a concurrent snapshot deletion was in progress
and ended up being aborted, it would be impossible to later attempt to
delete again the snapshot, since the root's send_in_progress counter could
never go back to 0.

We were also setting clone_sources_to_rollback to i + 1 too early - if we
bailed out because the clone root we got is not readonly or flagged as dead
we ended up later derreferencing a null pointer because we didn't assign
the clone root to sctx->clone_roots[i].root:

		for (i = 0; sctx && i < clone_sources_to_rollback; i++)
			btrfs_root_dec_send_in_progress(
					sctx->clone_roots[i].root);

So just don't increment the send_in_progress counter if the root is readonly
or flagged as dead.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2015-03-26 17:55:51 -07:00
Filipe Manana 5cc2b17e80 Btrfs: send, add missing check for dead clone root
After we locked the root's root item, a concurrent snapshot deletion
call might have set the dead flag on it. So check if the dead flag
is set and abort if it is, just like we do for the parent root.

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2015-03-26 17:55:51 -07:00
Filipe Manana 84471e2429 Btrfs: incremental send, don't rename a directory too soon
There's one more case where we can't issue a rename operation for a
directory as soon as we process it. We used to delay directory renames
only if they have some ancestor directory with a higher inode number
that got renamed too, but there's another case where we need to delay
the rename too - when a directory A is renamed to the old name of a
directory B but that directory B has its rename delayed because it
has now (in the send root) an ancestor with a higher inode number that
was renamed. If we don't delay the directory rename in this case, the
receiving end of the send stream will attempt to rename A to the old
name of B before B got renamed to its new name, which results in a
"directory not empty" error. So fix this by delaying directory renames
for this case too.

Steps to reproduce:

  $ mkfs.btrfs -f /dev/sdb
  $ mount /dev/sdb /mnt

  $ mkdir /mnt/a
  $ mkdir /mnt/b
  $ mkdir /mnt/c
  $ touch /mnt/a/file

  $ btrfs subvolume snapshot -r /mnt /mnt/snap1

  $ mv /mnt/c /mnt/x
  $ mv /mnt/a /mnt/x/y
  $ mv /mnt/b /mnt/a

  $ btrfs subvolume snapshot -r /mnt /mnt/snap2

  $ btrfs send /mnt/snap1 -f /tmp/1.send
  $ btrfs send -p /mnt/snap1 /mnt/snap2 -f /tmp/2.send

  $ mkfs.btrfs -f /dev/sdc
  $ mount /dev/sdc /mnt2
  $ btrfs receive /mnt2 -f /tmp/1.send
  $ btrfs receive /mnt2 -f /tmp/2.send
  ERROR: rename b -> a failed. Directory not empty

A test case for xfstests follows soon.

Reported-by: Ames Cornish <ames@cornishes.net>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2015-03-02 14:04:45 -08:00
David Sterba a937b9791e btrfs: kill btrfs_inode_*time helpers
They just opencode taking address of the timespec member.

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2015-02-02 18:39:07 -08:00
Filipe Manana e5fa8f865b Btrfs: ensure send always works on roots without orphans
Move the logic from the snapshot creation ioctl into send. This avoids
doing the transaction commit if send isn't used, and ensures that if
a crash/reboot happens after the transaction commit that created the
snapshot and before the transaction commit that switched the commit
root, send will not get a commit root that differs from the main root
(that has orphan items).

Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-11-25 07:41:23 -08:00
Chris Mason bbf65cf0b5 Merge branch 'cleanup/misc-for-3.18' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux into for-linus
Signed-off-by: Chris Mason <clm@fb.com>

Conflicts:
	fs/btrfs/extent_io.c
2014-10-04 09:56:45 -07:00
Filipe Manana bf8e8ca6fd Btrfs: send, don't delay dir move if there's a new parent inode
If between two snapshots we rename an existing directory named X to Y and
make it a child (direct or not) of a new inode named X, we were delaying
the move/rename of the former directory unnecessarily, which would result
in attempting to rename the new directory from its orphan name to name X
prematurely.

Minimal reproducer:

    $ mkfs.btrfs -f /dev/vdd
    $ mount /dev/vdd /mnt
    $ mkdir -p /mnt/merlin/RC/OSD/Source

    $ btrfs subvolume snapshot -r /mnt /mnt/mysnap1

    $ mkdir /mnt/OSD
    $ mv /mnt/merlin/RC/OSD /mnt/OSD/OSD-Plane_788
    $ mv /mnt/OSD /mnt/merlin/RC

    $ btrfs subvolume snapshot -r /mnt /mnt/mysnap2

    $ btrfs send /mnt/mysnap1 -f /tmp/1.snap
    $ btrfs send -p /mnt/mysnap1 /mnt/mysnap2 -f /tmp/2.snap

    $ mkfs.btrfs -f /dev/vdc
    $ mount /dev/vdc /mnt2

    $ btrfs receive /mnt2 -f /tmp/1.snap
    $ btrfs receive /mnt2 -f /tmp/2.snap

The second receive (from an incremental send) failed with the following
error message: "rename o261-7-0 -> merlin/RC/OSD failed".
This is a regression introduced in the 3.16 kernel.

A test case for xfstests follows.

Reported-by: Marc Merlin <marc@merlins.org>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-10-03 16:14:59 -07:00
David Sterba 2755a0de64 btrfs: hide typecast to definition of BTRFS_SEND_TRANS_STUB
Signed-off-by: David Sterba <dsterba@suse.cz>
2014-10-02 17:30:31 +02:00
Filipe Manana 4395e0c4da Btrfs: send, lower mem requirements for processing xattrs
Maximum xattr size can be up to nearly the leaf size. For an fs with a
leaf size larger than the page size, using kmalloc requires allocating
multiple pages that are contiguous, which might not be possible if
there's heavy memory fragmentation. Therefore fallback to vmalloc if
we fail to allocate with kmalloc. Also start with a smaller buffer size,
since xattr values typically are smaller than a page.

Reported-by: Chris Murphy <lists@colorremedies.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-09-17 13:38:16 -07:00
Fabian Frederick d447d0da44 Btrfs: fix sparse warning
Fix the following sparse warning:
fs/btrfs/send.c:518:51: warning: incorrect type in argument 2 (different address spaces)
fs/btrfs/send.c:518:51:    expected char const [noderef] <asn:1>*<noident>
fs/btrfs/send.c:518:51:    got char *

We can safely use (const char __user *) with set_fs(KERNEL_DS)

__force added to avoid sparse-all warning:
fs/btrfs/send.c:518:40: warning: cast adds address space to expression (<asn:1>)

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Reviewed-by: Zach Brown <zab@zabbo.net>
Signed-off-by: Chris Mason <clm@fb.com>
2014-09-17 13:37:35 -07:00
Filipe Manana 7e3ae33efa Btrfs: send, use the right limits for xattr names and values
We were limiting the sum of the xattr name and value lengths to PATH_MAX,
which is not correct, specially on filesystems created with btrfs-progs
v3.12 or higher, where the default leaf size is max(16384, PAGE_SIZE), or
systems with page sizes larger than 4096 bytes.

Xattrs have their own specific maximum name and value lengths, which depend
on the leaf size, therefore use these limits to be able to send xattrs with
sizes larger than PATH_MAX.

A test case for xfstests follows.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-06-09 17:21:00 -07:00
Filipe Manana 1af56070e3 Btrfs: send, don't error in the presence of subvols/snapshots
If we are doing an incremental send and the base snapshot has a
directory with name X that doesn't exist anymore in the second
snapshot and a new subvolume/snapshot exists in the second snapshot
that has the same name as the directory (name X), the incremental
send would fail with -ENOENT error. This is because it attempts
to lookup for an inode with a number matching the objectid of a
root, which doesn't exist.

Steps to reproduce:

    mkfs.btrfs -f /dev/sdd
    mount /dev/sdd /mnt

    mkdir /mnt/testdir
    btrfs subvolume snapshot -r /mnt /mnt/mysnap1

    rmdir /mnt/testdir
    btrfs subvolume create /mnt/testdir
    btrfs subvolume snapshot -r /mnt /mnt/mysnap2

    btrfs send -p /mnt/mysnap1 /mnt/mysnap2 -f /tmp/send.data

A test case for xfstests follows.

Reported-by: Robert White <rwhite@pobox.com>
Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-06-09 17:20:59 -07:00
David Sterba 351fd35321 btrfs: remove stale newlines from log messages
I've noticed an extra line after "use no compression", but search
revealed much more in messages of more critical levels and rare errors.

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2014-06-09 17:20:53 -07:00
Filipe Manana f959492fc1 Btrfs: send, fix more issues related to directory renames
This is a continuation of the previous changes titled:

   Btrfs: fix incremental send's decision to delay a dir move/rename
   Btrfs: part 2, fix incremental send's decision to delay a dir move/rename

There's a few more cases where a directory rename/move must be delayed which was
previously overlooked. If our immediate ancestor has a lower inode number than
ours and it doesn't have a delayed rename/move operation associated to it, it
doesn't mean there isn't any non-direct ancestor of our current inode that needs
to be renamed/moved before our current inode (i.e. with a higher inode number
than ours).

So we can't stop the search if our immediate ancestor has a lower inode number than
ours, we need to navigate the directory hierarchy upwards until we hit the root or:

1) find an ancestor with an higher inode number that was renamed/moved in the send
   root too (or already has a pending rename/move registered);
2) find an ancestor that is a new directory (higher inode number than ours and
   exists only in the send root).

Reproducer for case 1)

    $ mkfs.btrfs -f /dev/sdd
    $ mount /dev/sdd /mnt

    $ mkdir -p /mnt/a/b
    $ mkdir -p /mnt/a/c/d
    $ mkdir /mnt/a/b/e
    $ mkdir /mnt/a/c/d/f
    $ mv /mnt/a/b /mnt/a/c/d/2b
    $ mkdir /mnt/a/x
    $ mkdir /mnt/a/y

    $ btrfs subvolume snapshot -r /mnt /mnt/snap1
    $ btrfs send /mnt/snap1 -f /tmp/base.send

    $ mv /mnt/a/x /mnt/a/y
    $ mv /mnt/a/c/d/2b/e /mnt/a/c/d/2b/2e
    $ mv /mnt/a/c/d /mnt/a/h/2d
    $ mv /mnt/a/c /mnt/a/h/2d/2b/2c

    $ btrfs subvolume snapshot -r /mnt /mnt/snap2
    $ btrfs send -p /mnt/snap1 /mnt/snap2 -f /tmp/incremental.send

Simple reproducer for case 2)

    $ mkfs.btrfs -f /dev/sdd
    $ mount /dev/sdd /mnt

    $ mkdir -p /mnt/a/b
    $ mkdir /mnt/a/c
    $ mv /mnt/a/b /mnt/a/c/b2
    $ mkdir /mnt/a/e

    $ btrfs subvolume snapshot -r /mnt /mnt/snap1
    $ btrfs send /mnt/snap1 -f /tmp/base.send

    $ mv /mnt/a/c/b2 /mnt/a/e/b3
    $ mkdir /mnt/a/e/b3/f
    $ mkdir /mnt/a/h
    $ mv /mnt/a/c /mnt/a/e/b3/f/c2
    $ mv /mnt/a/e /mnt/a/h/e2

    $ btrfs subvolume snapshot -r /mnt /mnt/snap2
    $ btrfs send -p /mnt/snap1 /mnt/snap2 -f /tmp/incremental.send

Another simple reproducer for case 2)

    $ mkfs.btrfs -f /dev/sdd
    $ mount /dev/sdd /mnt

    $ mkdir -p /mnt/a/b
    $ mkdir /mnt/a/c
    $ mkdir /mnt/a/b/d
    $ mkdir /mnt/a/c/e

    $ btrfs subvolume snapshot -r /mnt /mnt/snap1
    $ btrfs send /mnt/snap1 -f /tmp/base.send

    $ mkdir /mnt/a/b/d/f
    $ mkdir /mnt/a/b/g
    $ mv /mnt/a/c/e /mnt/a/b/g/e2
    $ mv /mnt/a/c /mnt/a/b/d/f/c2
    $ mv /mnt/a/b/d/f /mnt/a/b/g/e2/f2

    $ btrfs subvolume snapshot -r /mnt /mnt/snap2
    $ btrfs send -p /mnt/snap1 /mnt/snap2 -f /tmp/incremental.send

More complex reproducer for case 2)

    $ mkfs.btrfs -f /dev/sdd
    $ mount /dev/sdd /mnt

    $ mkdir -p /mnt/a/b
    $ mkdir -p /mnt/a/c/d
    $ mkdir /mnt/a/b/e
    $ mkdir /mnt/a/c/d/f
    $ mv /mnt/a/b /mnt/a/c/d/2b
    $ mkdir /mnt/a/x
    $ mkdir /mnt/a/y

    $ btrfs subvolume snapshot -r /mnt /mnt/snap1
    $ btrfs send /mnt/snap1 -f /tmp/base.send

    $ mv /mnt/a/x /mnt/a/y
    $ mv /mnt/a/c/d/2b/e /mnt/a/c/d/2b/2e
    $ mv /mnt/a/c/d /mnt/a/h/2d
    $ mv /mnt/a/c /mnt/a/h/2d/2b/2c

    $ btrfs subvolume snapshot -r /mnt /mnt/snap2
    $ btrfs send -p /mnt/snap1 /mnt/snap2 -f /tmp/incremental.send

For both cases the incremental send would enter an infinite loop when building
path strings.

While solving these cases, this change also re-implements the code to detect
when directory moves/renames should be delayed. Instead of dealing with several
specific cases separately, it's now more generic handling all cases with a simple
detection algorithm and if when applying a delayed move/rename there's a path loop
detected, it further delays the move/rename registering a new ancestor inode as
the dependency inode (so our rename happens after that ancestor is renamed).

Tests for these cases is being added to xfstests too.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-06-09 17:20:40 -07:00
Filipe Manana a10c40766c Btrfs: send, remove dead code from __get_cur_name_and_parent
Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-06-09 17:20:39 -07:00
Filipe Manana c992ec94f2 Btrfs: send, account for orphan directories when building path strings
If we have directories with a pending move/rename operation, we must take into
account any orphan directories that got created before executing the pending
move/rename. Those orphan directories are directories with an inode number higher
then the current send progress and that don't exist in the parent snapshot, they
are created before current progress reaches their inode number, with a generated
name of the form oN-M-I and at the root of the filesystem tree, and later when
progress matches their inode number, moved/renamed to their final location.

Reproducer:

          $ mkfs.btrfs -f /dev/sdd
          $ mount /dev/sdd /mnt

          $ mkdir -p /mnt/a/b/c/d
          $ mkdir /mnt/a/b/e
          $ mv /mnt/a/b/c /mnt/a/b/e/CC
          $ mkdir /mnt/a/b/e/CC/d/f
	  $ mkdir /mnt/a/g

          $ btrfs subvolume snapshot -r /mnt /mnt/snap1
          $ btrfs send /mnt/snap1 -f /tmp/base.send

          $ mkdir /mnt/a/g/h
	  $ mv /mnt/a/b/e /mnt/a/g/h/EE
          $ mv /mnt/a/g/h/EE/CC/d /mnt/a/g/h/EE/DD

          $ btrfs subvolume snapshot -r /mnt /mnt/snap2
          $ btrfs send -p /mnt/snap1 /mnt/snap2 -f /tmp/incremental.send

The second receive command failed with the following error:

    ERROR: rename a/b/e/CC/d -> o264-7-0/EE/DD failed. No such file or directory

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>
2014-06-09 17:20:38 -07:00
Filipe Manana b46ab97bcd Btrfs: send, avoid unnecessary inode item lookup in the btree
Regardless of whether the caller is interested or not in knowing the inode's
generation (dir_gen != NULL), get_first_ref always does a btree lookup to get
the inode item. Avoid this useless lookup if dir_gen parameter is NULL (which
is in some cases).

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-06-09 17:20:37 -07:00
David Sterba 521e0546c9 btrfs: protect snapshots from deleting during send
The patch "Btrfs: fix protection between send and root deletion"
(18f687d538) does not actually prevent to delete the snapshot
and just takes care during background cleaning, but this seems rather
user unfriendly, this patch implements the idea presented in

http://www.spinics.net/lists/linux-btrfs/msg30813.html

- add an internal root_item flag to denote a dead root
- check if the send_in_progress is set and refuse to delete, otherwise
  set the flag and proceed
- check the flag in send similar to the btrfs_root_readonly checks, for
  all involved roots

The root lookup in send via btrfs_read_fs_root_no_name will check if the
root is really dead or not. If it is, ENOENT, aborted send. If it's
alive, it's protected by send_in_progress, send can continue.

CC: Miao Xie <miaox@cn.fujitsu.com>
CC: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2014-06-09 17:20:31 -07:00
Filipe Manana 01a9a8a9e2 Btrfs: send, fix corrupted path strings for long paths
If a path has more than 230 characters, we allocate a new buffer to
use for the path, but we were forgotting to copy the contents of the
previous buffer into the new one, which has random content from the
kmalloc call.

Test:

    mkfs.btrfs -f /dev/sdd
    mount /dev/sdd /mnt

    TEST_PATH="/mnt/fdmanana/.config/google-chrome-mysetup/Default/Pepper_Data/Shockwave_Flash/WritableRoot/#SharedObjects/JSHJ4ZKN/s.wsj.net/[[IMPORT]]/players.edgesuite.net/flash/plugins/osmf/advanced-streaming-plugin/v2.7/osmf1.6/Ak#"
    mkdir -p $TEST_PATH
    echo "hello world" > $TEST_PATH/amaiAdvancedStreamingPlugin.txt

    btrfs subvolume snapshot -r /mnt /mnt/mysnap1
    btrfs send /mnt/mysnap1 -f /tmp/1.snap

A test for xfstests follows.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Cc: Marc Merlin <marc@merlins.org>
Tested-by: Marc MERLIN <marc@merlins.org>
Signed-off-by: Chris Mason <clm@fb.com>
2014-06-06 12:00:46 -07:00
Filipe Manana 51a60253a5 Btrfs: send, fix incorrect ref access when using extrefs
When running send, if an inode only has extended reference items
associated to it and no regular references, send.c:get_first_ref()
was incorrectly assuming the reference it found was of type
BTRFS_INODE_REF_KEY due to use of the wrong key variable.
This caused weird behaviour when using the found item has a regular
reference, such as weird path string, and occasionally (when lucky)
a crash:

[  190.600652] general protection fault: 0000 [#1] SMP DEBUG_PAGEALLOC
[  190.600994] Modules linked in: btrfs xor raid6_pq binfmt_misc nfsd auth_rpcgss oid_registry nfs_acl nfs lockd fscache sunrpc psmouse serio_raw evbug pcspkr i2c_piix4 e1000 floppy
[  190.602565] CPU: 2 PID: 14520 Comm: btrfs Not tainted 3.13.0-fdm-btrfs-next-26+ #1
[  190.602728] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[  190.602868] task: ffff8800d447c920 ti: ffff8801fa79e000 task.ti: ffff8801fa79e000
[  190.603030] RIP: 0010:[<ffffffff813266b4>]  [<ffffffff813266b4>] memcpy+0x54/0x110
[  190.603262] RSP: 0018:ffff8801fa79f880  EFLAGS: 00010202
[  190.603395] RAX: ffff8800d4326e3f RBX: 000000000000036a RCX: ffff880000000000
[  190.603553] RDX: 000000000000032a RSI: ffe708844042936a RDI: ffff8800d43271a9
[  190.603710] RBP: ffff8801fa79f8c8 R08: 00000000003a4ef0 R09: 0000000000000000
[  190.603867] R10: 793a4ef09f000000 R11: 9f0000000053726f R12: ffff8800d43271a9
[  190.604020] R13: 0000160000000000 R14: ffff8802110134f0 R15: 000000000000036a
[  190.604020] FS:  00007fb423d09b80(0000) GS:ffff880216200000(0000) knlGS:0000000000000000
[  190.604020] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[  190.604020] CR2: 00007fb4229d4b78 CR3: 00000001f5d76000 CR4: 00000000000006e0
[  190.604020] Stack:
[  190.604020]  ffffffffa01f4d49 ffff8801fa79f8f0 00000000000009f9 ffff8801fa79f8c8
[  190.604020]  00000000000009f9 ffff880211013260 000000000000f971 ffff88021147dba8
[  190.604020]  00000000000009f9 ffff8801fa79f918 ffffffffa02367f5 ffff8801fa79f928
[  190.604020] Call Trace:
[  190.604020]  [<ffffffffa01f4d49>] ? read_extent_buffer+0xb9/0x120 [btrfs]
[  190.604020]  [<ffffffffa02367f5>] fs_path_add_from_extent_buffer+0x45/0x60 [btrfs]
[  190.604020]  [<ffffffffa0238806>] get_first_ref+0x1f6/0x210 [btrfs]
[  190.604020]  [<ffffffffa0238994>] __get_cur_name_and_parent+0x174/0x3a0 [btrfs]
[  190.604020]  [<ffffffff8118df3d>] ? kmem_cache_alloc_trace+0x11d/0x1e0
[  190.604020]  [<ffffffffa0236674>] ? fs_path_alloc+0x24/0x60 [btrfs]
[  190.604020]  [<ffffffffa0238c91>] get_cur_path+0xd1/0x240 [btrfs]
(...)

Steps to reproduce (either crash or some weirdness like an odd path string):

    mkfs.btrfs -f -O extref /dev/sdd
    mount /dev/sdd /mnt

    mkdir /mnt/testdir
    touch /mnt/testdir/foobar

    for i in `seq 1 2550`; do
        ln /mnt/testdir/foobar /mnt/testdir/foobar_link_`printf "%04d" $i`
    done

    ln /mnt/testdir/foobar /mnt/testdir/final_foobar_name

    rm -f /mnt/testdir/foobar
    for i in `seq 1 2550`; do
        rm -f /mnt/testdir/foobar_link_`printf "%04d" $i`
    done

    btrfs subvolume snapshot -r /mnt /mnt/mysnap
    btrfs send /mnt/mysnap -f /tmp/mysnap.send

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
2014-05-20 10:18:26 -07:00
Chris Mason cfd4a535b6 Btrfs: limit the path size in send to PATH_MAX
fs_path_ensure_buf is used to make sure our path buffers for
send are big enough for the path names as we construct them.
The buffer size is limited to 32K by the length field in
the struct.

But bugs in the path construction can end up trying to build
a huge buffer, and we'll do invalid memmmoves when the
buffer length field wraps.

This patch is step one, preventing the overflows.

Signed-off-by: Chris Mason <clm@fb.com>
2014-04-26 05:02:03 -07:00
Filipe Manana c715e155c9 Btrfs: send, build path string only once in send_hole
There's no point building the path string in each iteration of the
send_hole loop, as it produces always the same string.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-04-07 09:08:46 -07:00
Filipe Manana 766b5e5ae7 Btrfs: send, fix data corruption due to incorrect hole detection
During an incremental send, when we finish processing an inode (corresponding to
a regular file) we would assume the gap between the end of the last processed file
extent and the file's size corresponded to a file hole, and therefore incorrectly
send a bunch of zero bytes to overwrite that region in the file.

This affects only kernel 3.14.

Reproducer:

    mkfs.btrfs -f /dev/sdc
    mount /dev/sdc /mnt

    xfs_io -f -c "falloc -k 0 268435456" /mnt/foo

    btrfs subvolume snapshot -r /mnt /mnt/mysnap0

    xfs_io -c "pwrite -S 0x01 -b 9216 16190218 9216" /mnt/foo
    xfs_io -c "pwrite -S 0x02 -b 1121 198720104 1121" /mnt/foo
    xfs_io -c "pwrite -S 0x05 -b 9216 107887439 9216" /mnt/foo
    xfs_io -c "pwrite -S 0x06 -b 9216 225520207 9216" /mnt/foo
    xfs_io -c "pwrite -S 0x07 -b 67584 102138300 67584" /mnt/foo
    xfs_io -c "pwrite -S 0x08 -b 7000 94897484 7000" /mnt/foo
    xfs_io -c "pwrite -S 0x09 -b 113664 245083212 113664" /mnt/foo
    xfs_io -c "pwrite -S 0x10 -b 123 17937788 123" /mnt/foo
    xfs_io -c "pwrite -S 0x11 -b 39936 229573311 39936" /mnt/foo
    xfs_io -c "pwrite -S 0x12 -b 67584 174792222 67584" /mnt/foo
    xfs_io -c "pwrite -S 0x13 -b 9216 249253213 9216" /mnt/foo
    xfs_io -c "pwrite -S 0x16 -b 67584 150046083 67584" /mnt/foo
    xfs_io -c "pwrite -S 0x17 -b 39936 118246040 39936" /mnt/foo
    xfs_io -c "pwrite -S 0x18 -b 67584 215965442 67584" /mnt/foo
    xfs_io -c "pwrite -S 0x19 -b 33792 97096725 33792" /mnt/foo
    xfs_io -c "pwrite -S 0x20 -b 125952 166300596 125952" /mnt/foo
    xfs_io -c "pwrite -S 0x21 -b 123 1078957 123" /mnt/foo
    xfs_io -c "pwrite -S 0x25 -b 9216 212044492 9216" /mnt/foo
    xfs_io -c "pwrite -S 0x26 -b 7000 265037146 7000" /mnt/foo
    xfs_io -c "pwrite -S 0x27 -b 42757 215922685 42757" /mnt/foo
    xfs_io -c "pwrite -S 0x28 -b 7000 69865411 7000" /mnt/foo
    xfs_io -c "pwrite -S 0x29 -b 67584 67948958 67584" /mnt/foo
    xfs_io -c "pwrite -S 0x30 -b 39936 266967019 39936" /mnt/foo
    xfs_io -c "pwrite -S 0x31 -b 1121 19582453 1121" /mnt/foo
    xfs_io -c "pwrite -S 0x32 -b 17408 257710255 17408" /mnt/foo
    xfs_io -c "pwrite -S 0x33 -b 39936 3895518 39936" /mnt/foo
    xfs_io -c "pwrite -S 0x34 -b 125952 12045847 125952" /mnt/foo
    xfs_io -c "pwrite -S 0x35 -b 17408 19156379 17408" /mnt/foo
    xfs_io -c "pwrite -S 0x36 -b 39936 50160066 39936" /mnt/foo
    xfs_io -c "pwrite -S 0x37 -b 113664 9549793 113664" /mnt/foo
    xfs_io -c "pwrite -S 0x38 -b 105472 94391506 105472" /mnt/foo
    xfs_io -c "pwrite -S 0x39 -b 23552 143632863 23552" /mnt/foo
    xfs_io -c "pwrite -S 0x40 -b 39936 241283845 39936" /mnt/foo
    xfs_io -c "pwrite -S 0x41 -b 113664 199937606 113664" /mnt/foo
    xfs_io -c "pwrite -S 0x42 -b 67584 67380093 67584" /mnt/foo
    xfs_io -c "pwrite -S 0x43 -b 67584 26793129 67584" /mnt/foo
    xfs_io -c "pwrite -S 0x44 -b 39936 14421913 39936" /mnt/foo
    xfs_io -c "pwrite -S 0x45 -b 123 253097405 123" /mnt/foo
    xfs_io -c "pwrite -S 0x46 -b 1121 128233424 1121" /mnt/foo
    xfs_io -c "pwrite -S 0x47 -b 105472 91577959 105472" /mnt/foo
    xfs_io -c "pwrite -S 0x48 -b 1121 7245381 1121" /mnt/foo
    xfs_io -c "pwrite -S 0x49 -b 113664 182414694 113664" /mnt/foo
    xfs_io -c "pwrite -S 0x50 -b 9216 32750608 9216" /mnt/foo
    xfs_io -c "pwrite -S 0x51 -b 67584 266546049 67584" /mnt/foo
    xfs_io -c "pwrite -S 0x52 -b 67584 87969398 67584" /mnt/foo
    xfs_io -c "pwrite -S 0x53 -b 9216 260848797 9216" /mnt/foo
    xfs_io -c "pwrite -S 0x54 -b 39936 119461243 39936" /mnt/foo
    xfs_io -c "pwrite -S 0x55 -b 7000 200178693 7000" /mnt/foo
    xfs_io -c "pwrite -S 0x56 -b 9216 243316029 9216" /mnt/foo
    xfs_io -c "pwrite -S 0x57 -b 7000 209658229 7000" /mnt/foo
    xfs_io -c "pwrite -S 0x58 -b 101376 179745192 101376" /mnt/foo
    xfs_io -c "pwrite -S 0x59 -b 9216 64012300 9216" /mnt/foo
    xfs_io -c "pwrite -S 0x60 -b 125952 181705139 125952" /mnt/foo
    xfs_io -c "pwrite -S 0x61 -b 23552 235737348 23552" /mnt/foo
    xfs_io -c "pwrite -S 0x62 -b 113664 106021355 113664" /mnt/foo
    xfs_io -c "pwrite -S 0x63 -b 67584 135753552 67584" /mnt/foo
    xfs_io -c "pwrite -S 0x64 -b 23552 95730888 23552" /mnt/foo
    xfs_io -c "pwrite -S 0x65 -b 11 17311415 11" /mnt/foo
    xfs_io -c "pwrite -S 0x66 -b 33792 120695553 33792" /mnt/foo
    xfs_io -c "pwrite -S 0x67 -b 9216 17164631 9216" /mnt/foo
    xfs_io -c "pwrite -S 0x68 -b 9216 136065853 9216" /mnt/foo
    xfs_io -c "pwrite -S 0x69 -b 67584 37752198 67584" /mnt/foo
    xfs_io -c "pwrite -S 0x70 -b 101376 189717473 101376" /mnt/foo
    xfs_io -c "pwrite -S 0x71 -b 7000 227463698 7000" /mnt/foo
    xfs_io -c "pwrite -S 0x72 -b 9216 12655137 9216" /mnt/foo
    xfs_io -c "pwrite -S 0x73 -b 7000 7488866 7000" /mnt/foo
    xfs_io -c "pwrite -S 0x74 -b 113664 87813649 113664" /mnt/foo
    xfs_io -c "pwrite -S 0x75 -b 33792 25802183 33792" /mnt/foo
    xfs_io -c "pwrite -S 0x76 -b 39936 93524024 39936" /mnt/foo
    xfs_io -c "pwrite -S 0x77 -b 33792 113336388 33792" /mnt/foo
    xfs_io -c "pwrite -S 0x78 -b 105472 184955320 105472" /mnt/foo
    xfs_io -c "pwrite -S 0x79 -b 101376 225691598 101376" /mnt/foo
    xfs_io -c "pwrite -S 0x80 -b 23552 77023155 23552" /mnt/foo
    xfs_io -c "pwrite -S 0x81 -b 11 201888192 11" /mnt/foo
    xfs_io -c "pwrite -S 0x82 -b 11 115332492 11" /mnt/foo
    xfs_io -c "pwrite -S 0x83 -b 67584 230278015 67584" /mnt/foo
    xfs_io -c "pwrite -S 0x84 -b 11 120589073 11" /mnt/foo
    xfs_io -c "pwrite -S 0x85 -b 125952 202207819 125952" /mnt/foo
    xfs_io -c "pwrite -S 0x86 -b 113664 86672080 113664" /mnt/foo
    xfs_io -c "pwrite -S 0x87 -b 17408 208459603 17408" /mnt/foo
    xfs_io -c "pwrite -S 0x88 -b 7000 73372211 7000" /mnt/foo
    xfs_io -c "pwrite -S 0x89 -b 7000 42252122 7000" /mnt/foo
    xfs_io -c "pwrite -S 0x90 -b 23552 46784881 23552" /mnt/foo
    xfs_io -c "pwrite -S 0x91 -b 101376 63172351 101376" /mnt/foo
    xfs_io -c "pwrite -S 0x92 -b 23552 59341931 23552" /mnt/foo
    xfs_io -c "pwrite -S 0x93 -b 39936 239599283 39936" /mnt/foo
    xfs_io -c "pwrite -S 0x94 -b 67584 175643105 67584" /mnt/foo
    xfs_io -c "pwrite -S 0x97 -b 23552 105534880 23552" /mnt/foo
    xfs_io -c "pwrite -S 0x98 -b 113664 8236844 113664" /mnt/foo
    xfs_io -c "pwrite -S 0x99 -b 125952 144489686 125952" /mnt/foo
    xfs_io -c "pwrite -S 0xa0 -b 7000 73273112 7000" /mnt/foo
    xfs_io -c "pwrite -S 0xa1 -b 125952 194580243 125952" /mnt/foo
    xfs_io -c "pwrite -S 0xa2 -b 123 56296779 123" /mnt/foo
    xfs_io -c "pwrite -S 0xa3 -b 11 233066845 11" /mnt/foo
    xfs_io -c "pwrite -S 0xa4 -b 39936 197727090 39936" /mnt/foo
    xfs_io -c "pwrite -S 0xa5 -b 101376 53579812 101376" /mnt/foo
    xfs_io -c "pwrite -S 0xa6 -b 9216 85669738 9216" /mnt/foo
    xfs_io -c "pwrite -S 0xa7 -b 125952 21266322 125952" /mnt/foo
    xfs_io -c "pwrite -S 0xa8 -b 23552 125726568 23552" /mnt/foo
    xfs_io -c "pwrite -S 0xa9 -b 9216 18423680 9216" /mnt/foo
    xfs_io -c "pwrite -S 0xb0 -b 1121 165901483 1121" /mnt/foo

    btrfs subvolume snapshot -r /mnt /mnt/mysnap1

    xfs_io -c "pwrite -S 0xff -b 10 16190218 10" /mnt/foo

    btrfs subvolume snapshot -r /mnt /mnt/mysnap2

    md5sum /mnt/foo          # returns 79e53f1466bfc09fd82b450689e6119e
    md5sum /mnt/mysnap2/foo  # returns 79e53f1466bfc09fd82b450689e6119e too

    btrfs send /mnt/mysnap1 -f /tmp/1.snap
    btrfs send -p /mnt/mysnap1 /mnt/mysnap2 -f /tmp/2.snap

    mkfs.btrfs -f /dev/sdc
    mount /dev/sdc /mnt

    btrfs receive /mnt -f /tmp/1.snap
    btrfs receive /mnt -f /tmp/2.snap

    md5sum /mnt/mysnap2/foo  # returns 2bb414c5155767cedccd7063e51beabd !!

A testcase for xfstests follows soon too.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-04-07 09:08:45 -07:00
Josef Bacik 3f8a18cc53 Btrfs: hold the commit_root_sem when getting the commit root during send
We currently rely too heavily on roots being read-only to save us from just
accessing root->commit_root.  We can easily balance blocks out from underneath a
read only root, so to save us from getting screwed make sure we only access
root->commit_root under the commit root sem.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-04-07 09:08:39 -07:00
Josef Bacik 9e351cc862 Btrfs: remove transaction from send
Lets try this again.  We can deadlock the box if we send on a box and try to
write onto the same fs with the app that is trying to listen to the send pipe.
This is because the writer could get stuck waiting for a transaction commit
which is being blocked by the send.  So fix this by making sure looking at the
commit roots is always going to be consistent.  We do this by keeping track of
which roots need to have their commit roots swapped during commit, and then
taking the commit_root_sem and swapping them all at once.  Then make sure we
take a read lock on the commit_root_sem in cases where we search the commit root
to make sure we're always looking at a consistent view of the commit roots.
Previously we had problems with this because we would swap a fs tree commit root
and then swap the extent tree commit root independently which would cause the
backref walking code to screw up sometimes.  With this patch we no longer
deadlock and pass all the weird send/receive corner cases.  Thanks,

Reportedy-by: Hugo Mills <hugo@carfax.org.uk>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-04-06 17:39:30 -07:00
Josef Bacik a26e8c9f75 Btrfs: don't clear uptodate if the eb is under IO
So I have an awful exercise script that will run snapshot, balance and
send/receive in parallel.  This sometimes would crash spectacularly and when it
came back up the fs would be completely hosed.  Turns out this is because of a
bad interaction of balance and send/receive.  Send will hold onto its entire
path for the whole send, but its blocks could get relocated out from underneath
it, and because it doesn't old tree locks theres nothing to keep this from
happening.  So it will go to read in a slot with an old transid, and we could
have re-allocated this block for something else and it could have a completely
different transid.  But because we think it is invalid we clear uptodate and
re-read in the block.  If we do this before we actually write out the new block
we could write back stale data to the fs, and boom we're screwed.

Now we definitely need to fix this disconnect between send and balance, but we
really really need to not allow ourselves to accidently read in stale data over
new data.  So make sure we check if the extent buffer is not under io before
clearing uptodate, this will kick back EIO to the caller instead of reading in
stale data and keep us from corrupting the fs.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-04-06 17:34:37 -07:00
Chris Mason 73b802f447 btrfs: fix uninit variable warning
fs/btrfs/send.c:2926: warning: ‘entry’ may be used uninitialized in this
function

Signed-off-by: Chris Mason <clm@fb.com>
2014-03-21 15:30:44 -07:00
Filipe Manana bfa7e1f8be Btrfs: part 2, fix incremental send's decision to delay a dir move/rename
For an incremental send, fix the process of determining whether the directory
inode we're currently processing needs to have its move/rename operation delayed.

We were ignoring the fact that if the inode's new immediate ancestor has a higher
inode number than ours but wasn't renamed/moved, we might still need to delay our
move/rename, because some other ancestor directory higher in the hierarchy might
have an inode number higher than ours *and* was renamed/moved too - in this case
we have to wait for rename/move of that ancestor to happen before our current
directory's rename/move operation.

Simple steps to reproduce this issue:

      $ mkfs.btrfs -f /dev/sdd
      $ mount /dev/sdd /mnt

      $ mkdir -p /mnt/a/x1/x2
      $ mkdir /mnt/a/Z
      $ mkdir -p /mnt/a/x1/x2/x3/x4/x5

      $ btrfs subvolume snapshot -r /mnt /mnt/snap1
      $ btrfs send /mnt/snap1 -f /tmp/base.send

      $ mv /mnt/a/x1/x2/x3 /mnt/a/Z/X33
      $ mv /mnt/a/x1/x2 /mnt/a/Z/X33/x4/x5/X22

      $ btrfs subvolume snapshot -r /mnt /mnt/snap2
      $ btrfs send -p /mnt/snap1 /mnt/snap2 -f /tmp/incremental.send

The incremental send caused the kernel code to enter an infinite loop when
building the path string for directory Z after its references are processed.

A more complex scenario:

      $ mkfs.btrfs -f /dev/sdd
      $ mount /dev/sdd /mnt

      $ mkdir -p /mnt/a/b/c/d
      $ mkdir /mnt/a/b/c/d/e
      $ mkdir /mnt/a/b/c/d/f
      $ mv /mnt/a/b/c/d/e /mnt/a/b/c/d/f/E2
      $ mkdir /mmt/a/b/c/g
      $ mv /mnt/a/b/c/d /mnt/a/b/D2

      $ btrfs subvolume snapshot -r /mnt /mnt/snap1
      $ btrfs send /mnt/snap1 -f /tmp/base.send

      $ mkdir /mnt/a/o
      $ mv /mnt/a/b/c/g /mnt/a/b/D2/f/G2
      $ mv /mnt/a/b/D2 /mnt/a/b/dd
      $ mv /mnt/a/b/c /mnt/a/C2
      $ mv /mnt/a/b/dd/f /mnt/a/o/FF
      $ mv /mnt/a/b /mnt/a/o/FF/E2/BB

      $ btrfs subvolume snapshot -r /mnt /mnt/snap2
      $ btrfs send -p /mnt/snap1 /mnt/snap2 -f /tmp/incremental.send

A test case for xfstests follows.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-03-21 15:25:48 -07:00
Filipe Manana 7b119a8b89 Btrfs: fix incremental send's decision to delay a dir move/rename
It's possible to change the parent/child relationship between directories
in such a way that if a child directory has a higher inode number than
its parent, it doesn't necessarily means the child rename/move operation
can be performed immediately. The parent migth have its own rename/move
operation delayed, therefore in this case the child needs to have its
rename/move operation delayed too, and be performed after its new parent's
rename/move.

Steps to reproduce the issue:

      $ umount /mnt
      $ mkfs.btrfs -f /dev/sdd
      $ mount /dev/sdd /mnt

      $ mkdir /mnt/A
      $ mkdir /mnt/B
      $ mkdir /mnt/C
      $ mv /mnt/C /mnt/A
      $ mv /mnt/B /mnt/A/C
      $ mkdir /mnt/A/C/D

      $ btrfs subvolume snapshot -r /mnt /mnt/snap1
      $ btrfs send /mnt/snap1 -f /tmp/base.send

      $ mv /mnt/A/C/D /mnt/A/D2
      $ mv /mnt/A/C/B /mnt/A/D2/B2
      $ mv /mnt/A/C /mnt/A/D2/B2/C2

      $ btrfs subvolume snapshot -r /mnt /mnt/snap2
      $ btrfs send -p /mnt/snap1 /mnt/snap2 -f /tmp/incremental.send

The incremental send caused the kernel code to enter an infinite loop when
building the path string for directory C after its references are processed.

The necessary conditions here are that C has an inode number higher than both
A and B, and B as an higher inode number higher than A, and D has the highest
inode number, that is:
    inode_number(A) < inode_number(B) < inode_number(C) < inode_number(D)

The same issue could happen if after the first snapshot there's any number
of intermediary parent directories between A2 and B2, and between B2 and C2.

A test case for xfstests follows, covering this simple case and more advanced
ones, with files and hard links created inside the directories.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-03-21 15:24:27 -07:00
Filipe Manana 425b5dafc8 Btrfs: remove unnecessary inode generation lookup in send
No need to search in the send tree for the generation number of the inode,
we already have it in the recorded_ref structure passed to us.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-03-20 17:15:28 -07:00
Liu Bo 2131bcd38b Btrfs: add readahead for send_write
Btrfs send reads data from disk and then writes to a stream via pipe or
a file via flush.

Currently we're going to read each page a time, so every page results
in a disk read, which is not friendly to disks, esp. HDD.  Given that,
the performance can be gained by adding readahead for those pages.

Here is a quick test:
$ btrfs subvolume create send
$ xfs_io -f -c "pwrite 0 1G" send/foobar
$ btrfs subvolume snap -r send ro
$ time "btrfs send ro -f /dev/null"

           w/o             w
real    1m37.527s       0m9.097s
user    0m0.122s        0m0.086s
sys     0m53.191s       0m12.857s

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:19 -04:00
Liu Bo a4d96d6254 Btrfs: share the same code for __record_{new,deleted}_ref
This has no functional change, only picks out the same part of two functions,
and makes it shared.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:19 -04:00
Filipe Manana fcbd2154d1 Btrfs: avoid unnecessary utimes update in incremental send
When we're finishing processing of an inode, if we're dealing with a
directory inode that has a pending move/rename operation, we don't
need to send a utimes update instruction to the send stream, as we'll
do it later after doing the move/rename operation. Therefore we save
some time here building paths and doing btree lookups.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:18 -04:00
Liu Bo 644d1940ab Btrfs: skip search tree for REG files
It is really unnecessary to search tree again for @gen, @mode and @rdev
in the case of REG inodes' creation, as we've got btrfs_inode_item in sctx,
and @gen, @mode and @rdev can easily be fetched.

Signed-off-by: Liu Bo <bo.li.liu@oracle.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:17:01 -04:00
David Sterba 9c9ca00bd3 btrfs: send: simplify allocation code in fs_path_ensure_buf
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:16:59 -04:00
David Sterba 1b2782c8ed btrfs: send: fix old buffer length in fs_path_ensure_buf
In "btrfs: send: lower memory requirements in common case" the code to
save the old_buf_len was incorrectly moved to a wrong place and broke
the original logic.

Reported-by: Filipe David Manana <fdmanana@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
Reviewed-by: Filipe David Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:16:58 -04:00
Filipe Manana bf0d1f441d Btrfs: fix send issuing outdated paths for utimes, chown and chmod
When doing an incremental send, if we had a directory pending a move/rename
operation and none of its parents, except for the immediate parent, were
pending a move/rename, after processing the directory's references, we would
be issuing utimes, chown and chmod intructions against am outdated path - a
path which matched the one in the parent root.

This change also simplifies a bit the code that deals with building a path
for a directory which has a move/rename operation delayed.

Steps to reproduce:

    $ mkfs.btrfs -f /dev/sdb3
    $ mount /dev/sdb3 /mnt/btrfs
    $ mkdir -p /mnt/btrfs/a/b/c/d/e
    $ mkdir /mnt/btrfs/a/b/c/f
    $ chmod 0777 /mnt/btrfs/a/b/c/d/e
    $ btrfs subvolume snapshot -r /mnt/btrfs /mnt/btrfs/snap1
    $ btrfs send /mnt/btrfs/snap1 -f /tmp/base.send
    $ mv /mnt/btrfs/a/b/c/f /mnt/btrfs/a/b/f2
    $ mv /mnt/btrfs/a/b/c/d/e /mnt/btrfs/a/b/f2/e2
    $ mv /mnt/btrfs/a/b/c /mnt/btrfs/a/b/c2
    $ mv /mnt/btrfs/a/b/c2/d /mnt/btrfs/a/b/c2/d2
    $ chmod 0700 /mnt/btrfs/a/b/f2/e2
    $ btrfs subvolume snapshot -r /mnt/btrfs /mnt/btrfs/snap2
    $ btrfs send -p /mnt/btrfs/snap1 /mnt/btrfs/snap2 -f /tmp/incremental.send

    $ umount /mnt/btrfs
    $ mkfs.btrfs -f /dev/sdb3
    $ mount /dev/sdb3 /mnt/btrfs
    $ btrfs receive /mnt/btrfs -f /tmp/base.send
    $ btrfs receive /mnt/btrfs -f /tmp/incremental.send

The second btrfs receive command failed with:

    ERROR: chmod a/b/c/d/e failed. No such file or directory

A test case for xfstests follows.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:16:51 -04:00
Filipe Manana 9dc442143b Btrfs: fix send attempting to rmdir non-empty directories
The incremental send algorithm assumed that it was possible to issue
a directory remove (rmdir) if the the inode number it was currently
processing was greater than (or equal) to any inode that referenced
the directory's inode. This wasn't a valid assumption because any such
inode might be a child directory that is pending a move/rename operation,
because it was moved into a directory that has a higher inode number and
was moved/renamed too - in other words, the case the following commit
addressed:

    9f03740a95
    (Btrfs: fix infinite path build loops in incremental send)

This made an incremental send issue an rmdir operation before the
target directory was actually empty, which made btrfs receive fail.
Therefore it needs to wait for all pending child directory inodes to
be moved/renamed before sending an rmdir operation.

Simple steps to reproduce this issue:

    $ mkfs.btrfs -f /dev/sdb3
    $ mount /dev/sdb3 /mnt/btrfs
    $ mkdir -p /mnt/btrfs/a/b/c/x
    $ mkdir /mnt/btrfs/a/b/y
    $ btrfs subvolume snapshot -r /mnt/btrfs /mnt/btrfs/snap1
    $ btrfs send /mnt/btrfs/snap1 -f /tmp/base.send
    $ mv /mnt/btrfs/a/b/y /mnt/btrfs/a/b/YY
    $ mv /mnt/btrfs/a/b/c/x /mnt/btrfs/a/b/YY
    $ rmdir /mnt/btrfs/a/b/c
    $ btrfs subvolume snapshot -r /mnt/btrfs /mnt/btrfs/snap2
    $ btrfs send -p /mnt/btrfs/snap1 /mnt/btrfs/snap2 -f /tmp/incremental.send

    $ umount /mnt/btrfs
    $ mkfs.btrfs -f /dev/sdb3
    $ mount /dev/sdb3 /mnt/btrfs
    $ btrfs receive /mnt/btrfs -f /tmp/base.send
    $ btrfs receive /mnt/btrfs -f /tmp/incremental.send

The second btrfs receive command failed with:

    ERROR: rmdir o259-6-0 failed. Directory not empty

A test case for xfstests follows.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:16:49 -04:00
Filipe Manana 29d6d30f5c Btrfs: send, don't send rmdir for same target multiple times
When doing an incremental send, if we delete a directory that has N > 1
hardlinks for the same file and that file has the highest inode number
inside the directory contents, an incremental send would send N times an
rmdir operation against the directory. This made the btrfs receive command
fail on the second rmdir instruction, as the target directory didn't exist
anymore.

Steps to reproduce the issue:

    $ mkfs.btrfs -f /dev/sdb3
    $ mount /dev/sdb3 /mnt/btrfs
    $ mkdir -p /mnt/btrfs/a/b/c
    $ echo 'ola mundo' > /mnt/btrfs/a/b/c/foo.txt
    $ ln /mnt/btrfs/a/b/c/foo.txt /mnt/btrfs/a/b/c/bar.txt
    $ btrfs subvolume snapshot -r /mnt/btrfs /mnt/btrfs/snap1
    $ btrfs send /mnt/btrfs/snap1 -f /tmp/base.send
    $ rm -f /mnt/btrfs/a/b/c/foo.txt
    $ rm -f /mnt/btrfs/a/b/c/bar.txt
    $ rmdir /mnt/btrfs/a/b/c
    $ btrfs subvolume snapshot -r /mnt/btrfs /mnt/btrfs/snap2
    $ btrfs send -p /mnt/btrfs/snap1 /mnt/btrfs/snap2 -f /tmp/incremental.send

    $ umount /mnt/btrfs
    $ mkfs.btrfs -f /dev/sdb3
    $ mount /dev/sdb3 /mnt/btrfs
    $ btrfs receive /mnt/btrfs -f /tmp/base.send
    $ btrfs receive /mnt/btrfs -f /tmp/incremental.send

The second btrfs receive command failed with:

    ERROR: rmdir o259-6-0 failed. No such file or directory

A test case for xfstests follows.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:16:48 -04:00
Filipe Manana 2b863a135f Btrfs: incremental send, fix invalid path after dir rename
This fixes yet one more case not caught by the commit titled:

   Btrfs: fix infinite path build loops in incremental send

In this case, even before the initial full send, we have a directory
which is a child of a directory with a higher inode number. Then we
perform the initial send, and after we rename both the child and the
parent, without moving them around. After doing these 2 renames, an
incremental send sent a rename instruction for the child directory
which contained an invalid "from" path (referenced the parent's old
name, not the new one), which made the btrfs receive command fail.

Steps to reproduce:

    $ mkfs.btrfs -f /dev/sdb3
    $ mount /dev/sdb3 /mnt/btrfs
    $ mkdir -p /mnt/btrfs/a/b
    $ mkdir /mnt/btrfs/d
    $ mkdir /mnt/btrfs/a/b/c
    $ mv /mnt/btrfs/d /mnt/btrfs/a/b/c
    $ btrfs subvolume snapshot -r /mnt/btrfs /mnt/btrfs/snap1
    $ btrfs send /mnt/btrfs/snap1 -f /tmp/base.send
    $ mv /mnt/btrfs/a/b/c /mnt/btrfs/a/b/x
    $ mv /mnt/btrfs/a/b/x/d /mnt/btrfs/a/b/x/y
    $ btrfs subvolume snapshot -r /mnt/btrfs /mnt/btrfs/snap2
    $ btrfs send -p /mnt/btrfs/snap1 /mnt/btrfs/snap2 -f /tmp/incremental.send

    $ umout /mnt/btrfs
    $ mkfs.btrfs -f /dev/sdb3
    $ mount /dev/sdb3 /mnt/btrfs
    $ btrfs receive /mnt/btrfs -f /tmp/base.send
    $ btrfs receive /mnt/btrfs -f /tmp/incremental.send

The second btrfs receive command failed with:
  "ERROR: rename a/b/c/d -> a/b/x/y failed. No such file or directory"

A test case for xfstests follows.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:16:48 -04:00
Wang Shilong dcfd5ad2fc Revert "Btrfs: remove transaction from btrfs send"
This reverts commit 41ce9970a8.
Previously i was thinking we can use readonly root's commit root
safely while it is not true, readonly root may be cowed with the
following cases.

1.snapshot send root will cow source root.
2.balance,device operations will also cow readonly send root
to relocate.

So i have two ideas to make us safe to use commit root.

-->approach 1:
make it protected by transaction and end transaction properly and we research
next item from root node(see btrfs_search_slot_for_read()).

-->approach 2:
add another counter to local root structure to sync snapshot with send.
and add a global counter to sync send with exclusive device operations.

So with approach 2, send can use commit root safely, because we make sure
send root can not be cowed during send. Unfortunately, it make codes *ugly*
and more complex to maintain.

To make snapshot and send exclusively, device operations and send operation
exclusively with each other is a little confusing for common users.

So why not drop into previous way.

Cc: Josef Bacik <jbacik@fb.com>
Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:16:35 -04:00
David Sterba ace0105076 btrfs: send: lower memory requirements in common case
The fs_path structure uses an inline buffer and falls back to a chain of
allocations, but vmalloc is not necessary because PATH_MAX fits into
PAGE_SIZE.

The size of fs_path has been reduced to 256 bytes from PAGE_SIZE,
usually 4k. Experimental measurements show that most paths on a single
filesystem do not exceed 200 bytes, and these get stored into the inline
buffer directly, which is now 230 bytes. Longer paths are kmalloced when
needed.

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:15:50 -04:00
Filipe David Borba Manana dff6d0adbe Btrfs: make some tree searches in send.c more efficient
We have this pattern where we do search for a contiguous group of
items in a tree and everytime we find an item, we process it, then
we release our path, increment the offset of the search key, do
another full tree search and repeat these steps until a tree search
can't find more items we're interested in.

Instead of doing these full tree searches after processing each item,
just process the next item/slot in our leaf and don't release the path.
Since all these trees are read only and we always use the commit root
for a search and skip node/leaf locks, we're not affecting concurrency
on the trees.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:15:49 -04:00
Filipe David Borba Manana a0859c0998 Btrfs: use right extent item position in send when finding extent clones
This was a leftover from the commit:

   74dd17fbe3
   (Btrfs: fix btrfs send for inline items and compression)

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:15:48 -04:00
David Sterba 57fb8910c2 btrfs: send: remove BUG_ON from name_cache_delete
If cleaning the name cache fails, we could try to proceed at the cost of
some memory leak. This is not expected to happen often.

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:15:48 -04:00
David Sterba 4d1a63b21b btrfs: send: remove BUG from process_all_refs
There are only 2 static callers, the BUG would normally be never
reached, but let's be nice.

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:15:47 -04:00
David Sterba 1f5a7ff999 btrfs: send: squeeze bitfilelds in fs_path
We know that buf_len is at most PATH_MAX, 4k, and can merge it with the
reversed member. This saves 3 bytes in favor of inline_buf.

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:15:46 -04:00
David Sterba e25a812206 btrfs: send: remove virtual_mem member from fs_path
We don't need to keep track of that, it's available via is_vmalloc_addr.

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:15:45 -04:00
David Sterba b23ab57d48 btrfs: send: remove prepared member from fs_path
The member is used only to return value back from
fs_path_prepare_for_add, we can do it locally and save 8 bytes for the
inline_buf path.

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:15:44 -04:00
David Sterba 64792f2535 btrfs: send: replace check with an assert in gen_unique_name
The buffer passed to snprintf can hold the fully expanded format string,
64 = 3x largest ULL + 3x char + trailing null.  I don't think that removing the
check entirely is a good idea, hence the ASSERT.

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:15:44 -04:00
Filipe David Borba Manana 5ed7f9ff15 Btrfs: more send support for parent/child dir relationship inversion
The commit titled "Btrfs: fix infinite path build loops in incremental send"
didn't cover a particular case where the parent-child relationship inversion
of directories doesn't imply a rename of the new parent directory. This was
due to a simple logic mistake, a logical and instead of a logical or.

Steps to reproduce:

  $ mkfs.btrfs -f /dev/sdb3
  $ mount /dev/sdb3 /mnt/btrfs
  $ mkdir -p /mnt/btrfs/a/b/bar1/bar2/bar3/bar4
  $ btrfs subvol snapshot -r /mnt/btrfs /mnt/btrfs/snap1
  $ mv /mnt/btrfs/a/b/bar1/bar2/bar3/bar4 /mnt/btrfs/a/b/k44
  $ mv /mnt/btrfs/a/b/bar1/bar2/bar3 /mnt/btrfs/a/b/k44
  $ mv /mnt/btrfs/a/b/bar1/bar2 /mnt/btrfs/a/b/k44/bar3
  $ mv /mnt/btrfs/a/b/bar1 /mnt/btrfs/a/b/k44/bar3/bar2/k11
  $ btrfs subvol snapshot -r /mnt/btrfs /mnt/btrfs/snap2
  $ btrfs send -p /mnt/btrfs/snap1 /mnt/btrfs/snap2 > /tmp/incremental.send

A patch to update the test btrfs/030 from xfstests, so that it covers
this case, will be submitted soon.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:15:43 -04:00
Filipe David Borba Manana 03cb4fb9d8 Btrfs: fix send dealing with file renames and directory moves
This fixes a case that the commit titled:

   Btrfs: fix infinite path build loops in incremental send

didn't cover. If the parent-child relationship between 2 directories
is inverted, both get renamed, and the former parent has a file that
got renamed too (but remains a child of that directory), the incremental
send operation would use the file's old path after sending an unlink
operation for that old path, causing receive to fail on future operations
like changing owner, permissions or utimes of the corresponding inode.

This is not a regression from the commit mentioned before, as without
that commit we would fall into the issues that commit fixed, so it's
just one case that wasn't covered before.

Simple steps to reproduce this issue are:

      $ mkfs.btrfs -f /dev/sdb3
      $ mount /dev/sdb3 /mnt/btrfs
      $ mkdir -p /mnt/btrfs/a/b/c/d
      $ touch /mnt/btrfs/a/b/c/d/file
      $ mkdir -p /mnt/btrfs/a/b/x
      $ btrfs subvol snapshot -r /mnt/btrfs /mnt/btrfs/snap1
      $ mv /mnt/btrfs/a/b/x /mnt/btrfs/a/b/c/x2
      $ mv /mnt/btrfs/a/b/c/d /mnt/btrfs/a/b/c/x2/d2
      $ mv /mnt/btrfs/a/b/c/x2/d2/file /mnt/btrfs/a/b/c/x2/d2/file2
      $ btrfs subvol snapshot -r /mnt/btrfs /mnt/btrfs/snap2
      $ btrfs send -p /mnt/btrfs/snap1 /mnt/btrfs/snap2 > /tmp/incremental.send

A patch to update the test btrfs/030 from xfstests, so that it covers
this case, will be submitted soon.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:15:42 -04:00
Filipe David Borba Manana d86477b303 Btrfs: add missing error check in incremental send
Function wait_for_parent_move() returns negative value if an error
happened, 0 if we don't need to wait for the parent's move, and
1 if the wait is needed.
Before this change an error return value was being treated like the
return value 1, which was not correct.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
2014-03-10 15:15:40 -04:00
Filipe David Borba Manana 93de4ba864 Btrfs: use right clone root offset for compressed extents
For non compressed extents, iterate_extent_inodes() gives us offsets
that take into account the data offset from the file extent items, while
for compressed extents it doesn't. Therefore we have to adjust them before
placing them in a send clone instruction. Not doing this adjustment leads to
the receiving end requesting for a wrong a file range to the clone ioctl,
which results in different file content from the one in the original send
root.

Issue reproducible with the following excerpt from the test I made for
xfstests:

  _scratch_mkfs
  _scratch_mount "-o compress-force=lzo"

  $XFS_IO_PROG -f -c "truncate 118811" $SCRATCH_MNT/foo
  $XFS_IO_PROG -c "pwrite -S 0x0d -b 39987 92267 39987" $SCRATCH_MNT/foo

  $BTRFS_UTIL_PROG subvolume snapshot -r $SCRATCH_MNT $SCRATCH_MNT/mysnap1

  $XFS_IO_PROG -c "pwrite -S 0x3e -b 80000 200000 80000" $SCRATCH_MNT/foo
  $BTRFS_UTIL_PROG filesystem sync $SCRATCH_MNT
  $XFS_IO_PROG -c "pwrite -S 0xdc -b 10000 250000 10000" $SCRATCH_MNT/foo
  $XFS_IO_PROG -c "pwrite -S 0xff -b 10000 300000 10000" $SCRATCH_MNT/foo

  # will be used for incremental send to be able to issue clone operations
  $BTRFS_UTIL_PROG subvolume snapshot -r $SCRATCH_MNT $SCRATCH_MNT/clones_snap

  $BTRFS_UTIL_PROG subvolume snapshot -r $SCRATCH_MNT $SCRATCH_MNT/mysnap2

  $FSSUM_PROG -A -f -w $tmp/1.fssum $SCRATCH_MNT/mysnap1
  $FSSUM_PROG -A -f -w $tmp/2.fssum -x $SCRATCH_MNT/mysnap2/mysnap1 \
      -x $SCRATCH_MNT/mysnap2/clones_snap $SCRATCH_MNT/mysnap2
  $FSSUM_PROG -A -f -w $tmp/clones.fssum $SCRATCH_MNT/clones_snap \
      -x $SCRATCH_MNT/clones_snap/mysnap1 -x $SCRATCH_MNT/clones_snap/mysnap2

  $BTRFS_UTIL_PROG send $SCRATCH_MNT/mysnap1 -f $tmp/1.snap
  $BTRFS_UTIL_PROG send $SCRATCH_MNT/clones_snap -f $tmp/clones.snap
  $BTRFS_UTIL_PROG send -p $SCRATCH_MNT/mysnap1 \
      -c $SCRATCH_MNT/clones_snap $SCRATCH_MNT/mysnap2 -f $tmp/2.snap

  _scratch_unmount
  _scratch_mkfs
  _scratch_mount

  $BTRFS_UTIL_PROG receive $SCRATCH_MNT -f $tmp/1.snap
  $FSSUM_PROG -r $tmp/1.fssum $SCRATCH_MNT/mysnap1 2>> $seqres.full

  $BTRFS_UTIL_PROG receive $SCRATCH_MNT -f $tmp/clones.snap
  $FSSUM_PROG -r $tmp/clones.fssum $SCRATCH_MNT/clones_snap 2>> $seqres.full

  $BTRFS_UTIL_PROG receive $SCRATCH_MNT -f $tmp/2.snap
  $FSSUM_PROG -r $tmp/2.fssum $SCRATCH_MNT/mysnap2 2>> $seqres.full

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-02-15 08:04:27 -08:00
Josef Bacik 6cc98d90f8 Btrfs: fix assert screwup for the pending move stuff
Wang noticed that he was failing btrfs/030 even though me and Filipe couldn't
reproduce.  Turns out this is because Wang didn't have CONFIG_BTRFS_ASSERT set,
which meant that a key part of Filipe's original patch was not being built in.
This appears to be a mess up with merging Filipe's patch as it does not exist in
his original patch.  Fix this by changing how we make sure del_waiting_dir_move
asserts that it did not error and take the function out of the ifdef check.
This makes btrfs/030 pass with the assert on or off.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fb.com>
Reviewed-by: Filipe Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-02-08 17:57:15 -08:00
Filipe David Borba Manana 0b947aff15 Btrfs: use btrfs_crc32c everywhere instead of libcrc32c
After the commit titled "Btrfs: fix btrfs boot when compiled as built-in",
LIBCRC32C requirement was removed from btrfs' Kconfig. This made it not
possible to build a kernel with btrfs enabled (either as module or built-in)
if libcrc32c is not enabled as well. So just replace all uses of libcrc32c
with the equivalent function in btrfs hash.h - btrfs_crc32c.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-02-03 09:01:27 -08:00
Chris Mason 514ac8ad87 Btrfs: don't use ram_bytes for uncompressed inline items
If we truncate an uncompressed inline item, ram_bytes isn't updated to reflect
the new size.  The fixe uses the size directly from the item header when
reading uncompressed inlines, and also fixes truncate to update the
size as it goes.

Reported-by: Jens Axboe <axboe@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
CC: stable@vger.kernel.org
2014-01-29 07:06:29 -08:00
Filipe David Borba Manana bf54f412f0 Btrfs: fix send file hole detection leading to data corruption
There was a case where file hole detection was incorrect and it would
cause an incremental send to override a section of a file with zeroes.

This happened in the case where between the last leaf we processed which
contained a file extent item for our current inode and the leaf we're
currently are at (and has a file extent item for our current inode) there
are only leafs containing exclusively file extent items for our current
inode, and none of them was updated since the previous send operation.
The file hole detection code would incorrectly consider the file range
covered by these leafs as a hole.

A test case for xfstests follows soon.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-29 07:06:25 -08:00
Filipe David Borba Manana 7fdd29d02e Btrfs: make send's file extent item search more efficient
Instead of looking for a file extent item, process it, release the path
and do a btree search for the next file extent item, just process all
file extent items in a leaf without intermediate btree searches. This way
we save cpu and we're not blocking other tasks or affecting concurrency on
the btree, because send's paths use the commit root and skip btree node/leaf
locking.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-29 07:06:24 -08:00
Filipe David Borba Manana 9f03740a95 Btrfs: fix infinite path build loops in incremental send
The send operation processes inodes by their ascending number, and assumes
that any rename/move operation can be successfully performed (sent to the
caller) once all previous inodes (those with a smaller inode number than the
one we're currently processing) were processed.

This is not true when an incremental send had to process an hierarchical change
between 2 snapshots where the parent-children relationship between directory
inodes was reversed - that is, parents became children and children became
parents. This situation made the path building code go into an infinite loop,
which kept allocating more and more memory that eventually lead to a krealloc
warning being displayed in dmesg:

  WARNING: CPU: 1 PID: 5705 at mm/page_alloc.c:2477 __alloc_pages_nodemask+0x365/0xad0()
  Modules linked in: btrfs raid6_pq xor pci_stub vboxpci(O) vboxnetadp(O) vboxnetflt(O) vboxdrv(O) snd_hda_codec_hdmi snd_hda_codec_realtek joydev radeon snd_hda_intel snd_hda_codec snd_hwdep snd_seq_midi snd_pcm psmouse i915 snd_rawmidi serio_raw snd_seq_midi_event lpc_ich snd_seq snd_timer ttm snd_seq_device rfcomm drm_kms_helper parport_pc bnep bluetooth drm ppdev snd soundcore i2c_algo_bit snd_page_alloc binfmt_misc video lp parport r8169 mii hid_generic usbhid hid
  CPU: 1 PID: 5705 Comm: btrfs Tainted: G           O 3.13.0-rc7-fdm-btrfs-next-18+ #3
  Hardware name: To Be Filled By O.E.M. To Be Filled By O.E.M./Z77 Pro4, BIOS P1.50 09/04/2012
  [ 5381.660441]  00000000000009ad ffff8806f6f2f4e8 ffffffff81777434 0000000000000007
  [ 5381.660447]  0000000000000000 ffff8806f6f2f528 ffffffff8104a9ec ffff8807038f36f0
  [ 5381.660452]  0000000000000000 0000000000000206 ffff8807038f2490 ffff8807038f36f0
  [ 5381.660457] Call Trace:
  [ 5381.660464]  [<ffffffff81777434>] dump_stack+0x4e/0x68
  [ 5381.660471]  [<ffffffff8104a9ec>] warn_slowpath_common+0x8c/0xc0
  [ 5381.660476]  [<ffffffff8104aa3a>] warn_slowpath_null+0x1a/0x20
  [ 5381.660480]  [<ffffffff81144995>] __alloc_pages_nodemask+0x365/0xad0
  [ 5381.660487]  [<ffffffff8108313f>] ? local_clock+0x4f/0x60
  [ 5381.660491]  [<ffffffff811430e8>] ? free_one_page+0x98/0x440
  [ 5381.660495]  [<ffffffff8108313f>] ? local_clock+0x4f/0x60
  [ 5381.660502]  [<ffffffff8113fae4>] ? __get_free_pages+0x14/0x50
  [ 5381.660508]  [<ffffffff81095fb8>] ? trace_hardirqs_off_caller+0x28/0xd0
  [ 5381.660515]  [<ffffffff81183caf>] alloc_pages_current+0x10f/0x1f0
  [ 5381.660520]  [<ffffffff8113fae4>] ? __get_free_pages+0x14/0x50
  [ 5381.660524]  [<ffffffff8113fae4>] __get_free_pages+0x14/0x50
  [ 5381.660530]  [<ffffffff8115dace>] kmalloc_order_trace+0x3e/0x100
  [ 5381.660536]  [<ffffffff81191ea0>] __kmalloc_track_caller+0x220/0x230
  [ 5381.660560]  [<ffffffffa0729fdb>] ? fs_path_ensure_buf.part.12+0x6b/0x200 [btrfs]
  [ 5381.660564]  [<ffffffff8178085c>] ? retint_restore_args+0xe/0xe
  [ 5381.660569]  [<ffffffff811580ef>] krealloc+0x6f/0xb0
  [ 5381.660586]  [<ffffffffa0729fdb>] fs_path_ensure_buf.part.12+0x6b/0x200 [btrfs]
  [ 5381.660601]  [<ffffffffa072a208>] fs_path_prepare_for_add+0x98/0xb0 [btrfs]
  [ 5381.660615]  [<ffffffffa072a2bc>] fs_path_add_path+0x2c/0x60 [btrfs]
  [ 5381.660628]  [<ffffffffa072c55c>] get_cur_path+0x7c/0x1c0 [btrfs]

Even without this loop, the incremental send couldn't succeed, because it would attempt
to send a rename/move operation for the lower inode before the highest inode number was
renamed/move. This issue is easy to trigger with the following steps:

  $ mkfs.btrfs -f /dev/sdb3
  $ mount /dev/sdb3 /mnt/btrfs
  $ mkdir -p /mnt/btrfs/a/b/c/d
  $ mkdir /mnt/btrfs/a/b/c2
  $ btrfs subvol snapshot -r /mnt/btrfs /mnt/btrfs/snap1
  $ mv /mnt/btrfs/a/b/c/d /mnt/btrfs/a/b/c2/d2
  $ mv /mnt/btrfs/a/b/c /mnt/btrfs/a/b/c2/d2/cc
  $ btrfs subvol snapshot -r /mnt/btrfs /mnt/btrfs/snap2
  $ btrfs send -p /mnt/btrfs/snap1 /mnt/btrfs/snap2 > /tmp/incremental.send

The structure of the filesystem when the first snapshot is taken is:

	 .                       (ino 256)
	 |-- a                   (ino 257)
	     |-- b               (ino 258)
	         |-- c           (ino 259)
	         |   |-- d       (ino 260)
                 |
	         |-- c2          (ino 261)

And its structure when the second snapshot is taken is:

	 .                       (ino 256)
	 |-- a                   (ino 257)
	     |-- b               (ino 258)
	         |-- c2          (ino 261)
	             |-- d2      (ino 260)
	                 |-- cc  (ino 259)

Before the move/rename operation is performed for the inode 259, the
move/rename for inode 260 must be performed, since 259 is now a child
of 260.

A test case for xfstests, with a more complex scenario, will follow soon.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-29 07:06:22 -08:00
Filipe David Borba Manana f74b86d855 Btrfs: fix snprintf usage by send's gen_unique_name
The buffer size argument passed to snprintf must account for the
trailing null byte added by snprintf, and it returns a value >= then
sizeof(buffer) when the string can't fit in the buffer.

Since our buffer has a size of 64 characters, and the maximum orphan
name we can generate is 63 characters wide, we must pass 64 as the
buffer size to snprintf, and not 63.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:20:43 -08:00
Wang Shilong ffcfaf8179 Btrfs: fix wrong search path initialization before searching tree root
To search tree root without transaction protection, we should neither search commit
root nor skip locking here, 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>
2014-01-28 13:20:37 -08:00
Filipe David Borba Manana 28e5dd8f35 Btrfs: fix send to not send non-aligned clone operations
It is possible for the send feature to send clone operations that
request a cloning range (offset + length) that is not aligned with
the block size. This makes the btrfs receive command send issue a
clone ioctl call that will fail, as the ioctl will return an -EINVAL
error because of the unaligned range.

Fix this by not sending clone operations for non block aligned ranges,
and instead send regular write operation for these (less common) cases.

The following xfstest reproduces this issue, which fails on the second
btrfs receive command without this change:

  seq=`basename $0`
  seqres=$RESULT_DIR/$seq
  echo "QA output created by $seq"

  tmp=`mktemp -d`

  status=1	# failure is the default!
  trap "_cleanup; exit \$status" 0 1 2 3 15

  _cleanup()
  {
      rm -fr $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

  rm -f $seqres.full

  _scratch_mkfs >/dev/null 2>&1
  _scratch_mount

  $XFS_IO_PROG -f -c "truncate 819200" $SCRATCH_MNT/foo | _filter_xfs_io
  $BTRFS_UTIL_PROG filesystem sync $SCRATCH_MNT | _filter_scratch

  $XFS_IO_PROG -c "falloc -k 819200 667648" $SCRATCH_MNT/foo | _filter_xfs_io
  $BTRFS_UTIL_PROG filesystem sync $SCRATCH_MNT | _filter_scratch

  $XFS_IO_PROG -f -c "pwrite 1482752 2978" $SCRATCH_MNT/foo | _filter_xfs_io
  $BTRFS_UTIL_PROG filesystem sync $SCRATCH_MNT | _filter_scratch

  $BTRFS_UTIL_PROG subvol snapshot -r $SCRATCH_MNT $SCRATCH_MNT/mysnap1 | \
      _filter_scratch

  $XFS_IO_PROG -f -c "truncate 883305" $SCRATCH_MNT/foo | _filter_xfs_io
  $BTRFS_UTIL_PROG filesystem sync $SCRATCH_MNT | _filter_scratch

  $BTRFS_UTIL_PROG subvol snapshot -r $SCRATCH_MNT $SCRATCH_MNT/mysnap2 | \
      _filter_scratch

  $BTRFS_UTIL_PROG send $SCRATCH_MNT/mysnap1 -f $tmp/1.snap 2>&1 | _filter_scratch
  $BTRFS_UTIL_PROG send -p $SCRATCH_MNT/mysnap1 $SCRATCH_MNT/mysnap2 \
      -f $tmp/2.snap 2>&1 | _filter_scratch

  md5sum $SCRATCH_MNT/foo | _filter_scratch
  md5sum $SCRATCH_MNT/mysnap1/foo | _filter_scratch
  md5sum $SCRATCH_MNT/mysnap2/foo | _filter_scratch

  _scratch_unmount
  _check_btrfs_filesystem $SCRATCH_DEV
  _scratch_mkfs >/dev/null 2>&1
  _scratch_mount

  $BTRFS_UTIL_PROG receive $SCRATCH_MNT -f $tmp/1.snap
  md5sum $SCRATCH_MNT/mysnap1/foo | _filter_scratch

  $BTRFS_UTIL_PROG receive $SCRATCH_MNT -f $tmp/2.snap
  md5sum $SCRATCH_MNT/mysnap2/foo | _filter_scratch

  _scratch_unmount
  _check_btrfs_filesystem $SCRATCH_DEV

  status=0
  exit

The tests expected output is:

  QA output created by 025
  FSSync 'SCRATCH_MNT'
  FSSync 'SCRATCH_MNT'
  wrote 2978/2978 bytes at offset 1482752
  XXX Bytes, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
  FSSync 'SCRATCH_MNT'
  Create a readonly snapshot of 'SCRATCH_MNT' in 'SCRATCH_MNT/mysnap1'
  FSSync 'SCRATCH_MNT'
  Create a readonly snapshot of 'SCRATCH_MNT' in 'SCRATCH_MNT/mysnap2'
  At subvol SCRATCH_MNT/mysnap1
  At subvol SCRATCH_MNT/mysnap2
  129b8eaee8d3c2bcad49bec596591cb3  SCRATCH_MNT/foo
  42b6369eae2a8725c1aacc0440e597aa  SCRATCH_MNT/mysnap1/foo
  129b8eaee8d3c2bcad49bec596591cb3  SCRATCH_MNT/mysnap2/foo
  At subvol mysnap1
  42b6369eae2a8725c1aacc0440e597aa  SCRATCH_MNT/mysnap1/foo
  At snapshot mysnap2
  129b8eaee8d3c2bcad49bec596591cb3  SCRATCH_MNT/mysnap2/foo

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:20:32 -08:00
Wang Shilong 8e56338d7d Btrfs: remove unnecessary transaction commit before send
We will finish orphan cleanups during snapshot, so we don't
have to commit transaction here.

Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Reviewed-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:20:22 -08:00
Wang Shilong 18f687d538 Btrfs: fix protection between send and root deletion
We should gurantee that parent and clone roots can not be destroyed
during send, for this we have two ideas.

1.by holding @subvol_sem, this might be a nightmare, because it will
block all subvolumes deletion for a long time.

2.Miao pointed out we can reuse @send_in_progress, that mean we will
skip snapshot deletion if root sending is in progress.

Here we adopt the second approach since it won't block other subvolumes
deletion for a long time.

Besides in btrfs_clean_one_deleted_snapshot(), we only check first root
, if this root is involved in send, we return directly rather than
continue to check.There are several reasons about it:

1.this case happen seldomly.
2.after sending,cleaner thread can continue to drop that root.
3.make code simple

Cc: David Sterba <dsterba@suse.cz>
Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Reviewed-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:20:21 -08:00
Wang Shilong 896c14f97f Btrfs: fix wrong send_in_progress accounting
Steps to reproduce:
 # mkfs.btrfs -f /dev/sda8
 # mount /dev/sda8 /mnt
 # btrfs sub snapshot -r /mnt /mnt/snap1
 # btrfs sub snapshot -r /mnt /mnt/snap2
 # btrfs send /mnt/snap1 -p /mnt/snap2 -f /mnt/1
 # dmesg

The problem is that we will sort clone roots(include @send_root), it
might push @send_root before thus @send_root's @send_in_progress will
be decreased twice.

Cc: David Sterba <dsterba@suse.cz>
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>
2014-01-28 13:20:21 -08:00
Frank Holton efe120a067 Btrfs: convert printk to btrfs_ and fix BTRFS prefix
Convert all applicable cases of printk and pr_* to the btrfs_* macros.

Fix all uses of the BTRFS prefix.

Signed-off-by: Frank Holton <fholton@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:20:05 -08:00
David Sterba 66ef7d65c3 btrfs: check balance of send_in_progress
Warn if the balance goes below zero, which appears to be unlikely
though. Otherwise cleans up the code a bit.

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:20:04 -08:00
Wang Shilong 41ce9970a8 Btrfs: remove transaction from btrfs send
Since daivd did the work that force us to use readonly snapshot,
we can safely remove transaction protection from btrfs send.

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>
2014-01-28 13:20:03 -08:00
David Sterba 2c68653787 btrfs: Check read-only status of roots during send
All the subvolues that are involved in send must be read-only during the
whole operation. The ioctl SUBVOL_SETFLAGS could be used to change the
status to read-write and the result of send stream is undefined if the
data change unexpectedly.

Fix that by adding a refcount for all involved roots and verify that
there's no send in progress during SUBVOL_SETFLAGS ioctl call that does
read-only -> read-write transition.

We need refcounts because there are no restrictions on number of send
parallel operations currently run on a single subvolume, be it source,
parent or one of the multiple clone sources.

Kernel is silent when the RO checks fail and returns EPERM. The same set
of checks is done already in userspace before send starts.

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:20:01 -08:00
David Sterba a8d89f5ba0 btrfs: remove unused mnt from send_ctx
Unused since ed2590953b
"Btrfs: stop using vfs_read in send".

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:20:01 -08:00
David Sterba 95bc79d50d btrfs: send: clean up dead code
Remove ifdefed code:

- tlv_put for 8, 16 and 32, add a generic tempalte if needed in future
- tlv_put_timespec - the btrfs_timespec fields are used
- fs_path_remove obsoleted long ago

Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:20:00 -08:00
Filipe David Borba Manana 5a0f4e2c2b Btrfs: fix pass of transid with wrong endianness in send.c
fs/btrfs/send.c:2190:9: warning: incorrect type in argument 3 (different base types)
fs/btrfs/send.c:2190:9:    expected unsigned long long [unsigned] [usertype] value
fs/btrfs/send.c:2190:9:    got restricted __le64 [usertype] ctransid
fs/btrfs/send.c:2195:17: warning: incorrect type in argument 3 (different base types)
fs/btrfs/send.c:2195:17:    expected unsigned long long [unsigned] [usertype] value
fs/btrfs/send.c:2195:17:    got restricted __le64 [usertype] ctransid
fs/btrfs/send.c:3716:9: warning: incorrect type in argument 3 (different base types)
fs/btrfs/send.c:3716:9:    expected unsigned long long [unsigned] [usertype] value
fs/btrfs/send.c:3716:9:    got restricted __le64 [usertype] ctransid

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:19:51 -08:00
Josef Bacik 16e7549f04 Btrfs: incompatible format change to remove hole extents
Btrfs has always had these filler extent data items for holes in inodes.  This
has made somethings very easy, like logging hole punches and sending hole
punches.  However for large holey files these extent data items are pure
overhead.  So add an incompatible feature to no longer add hole extents to
reduce the amount of metadata used by these sort of files.  This has a few
changes for logging and send obviously since they will need to detect holes and
log/send the holes if there are any.  I've tested this thoroughly with xfstests
and it doesn't cause any issues with and without the incompat format set.
Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-28 13:19:21 -08:00
Dan Carpenter 700ff4f095 Btrfs: fix access_ok() check in btrfs_ioctl_send()
The closing parenthesis is in the wrong place.  We want to check
"sizeof(*arg->clone_sources) * arg->clone_sources_count" instead of
"sizeof(*arg->clone_sources * arg->clone_sources_count)".

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Jie Liu <jeff.liu@oracle.com>
Signed-off-by: Chris Mason <clm@fb.com>
cc: stable@vger.kernel.org
2013-12-12 07:13:02 -08:00
Josef Bacik 007d31f755 Btrfs: check file extent type before anything else
I hit this problem with my no holes patch and it made me realize what the
problem was for bz 60834.  If the first item in the leaf is an inline extent and
we try to read anything starting from disk_bytenr onward we will read off the
end of the leaf.  So we need to check to see what it's type is, and if it's not
REG we can just break out.  This should fix this problem.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-11-11 22:12:49 -05:00
Dulshani Gunawardhana fae7f21cec btrfs: Use WARN_ON()'s return value in place of WARN_ON(1)
Use WARN_ON()'s return value in place of WARN_ON(1) for cleaner source
code that outputs a more descriptive warnings. Also fix the styling
warning of redundant braces that came up as a result of this fix.

Signed-off-by: Dulshani Gunawardhana <dulshani.gunawardhana89@gmail.com>
Reviewed-by: Zach Brown <zab@redhat.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-11-11 22:11:53 -05:00
Josef Bacik ed2590953b Btrfs: stop using vfs_read in send
Apparently we don't actually close the files until we return to userspace, so
stop using vfs_read in send.  This is actually better for us since we can avoid
all the extra logic of holding the file we're sending open and making sure to
clean it up.  This will fix people who have been hitting too many files open
errors when trying to send.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-11-11 22:07:11 -05:00
Ross Kirk dd3cc16b87 btrfs: drop unused parameter from btrfs_item_nr
Remove unused eb parameter from btrfs_item_nr

Signed-off-by: Ross Kirk <ross.kirk@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-11-11 21:50:48 -05:00
Linus Torvalds b7c09ad401 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs updates from Chris Mason:
 "This is against 3.11-rc7, but was pulled and tested against your tree
  as of yesterday.  We do have two small incrementals queued up, but I
  wanted to get this bunch out the door before I hop on an airplane.

  This is a fairly large batch of fixes, performance improvements, and
  cleanups from the usual Btrfs suspects.

  We've included Stefan Behren's work to index subvolume UUIDs, which is
  targeted at speeding up send/receive with many subvolumes or snapshots
  in place.  It closes a long standing performance issue that was built
  in to the disk format.

  Mark Fasheh's offline dedup work is also here.  In this case offline
  means the FS is mounted and active, but the dedup work is not done
  inline during file IO.  This is a building block where utilities are
  able to ask the FS to dedup a series of extents.  The kernel takes
  care of verifying the data involved really is the same.  Today this
  involves reading both extents, but we'll continue to evolve the
  patches"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs: (118 commits)
  Btrfs: optimize key searches in btrfs_search_slot
  Btrfs: don't use an async starter for most of our workers
  Btrfs: only update disk_i_size as we remove extents
  Btrfs: fix deadlock in uuid scan kthread
  Btrfs: stop refusing the relocation of chunk 0
  Btrfs: fix memory leak of uuid_root in free_fs_info
  btrfs: reuse kbasename helper
  btrfs: return btrfs error code for dev excl ops err
  Btrfs: allow partial ordered extent completion
  Btrfs: convert all bug_ons in free-space-cache.c
  Btrfs: add support for asserts
  Btrfs: adjust the fs_devices->missing count on unmount
  Btrf: cleanup: don't check for root_refs == 0 twice
  Btrfs: fix for patch "cleanup: don't check the same thing twice"
  Btrfs: get rid of one BUG() in write_all_supers()
  Btrfs: allocate prelim_ref with a slab allocater
  Btrfs: pass gfp_t to __add_prelim_ref() to avoid always using GFP_ATOMIC
  Btrfs: fix race conditions in BTRFS_IOC_FS_INFO ioctl
  Btrfs: fix race between removing a dev and writing sbs
  Btrfs: remove ourselves from the cluster list under lock
  ...
2013-09-12 09:58:51 -07:00
Andy Shevchenko ed84885d1e btrfs: reuse kbasename helper
To get name of the file from a pathname let's use kbasename() helper. It allows
to simplify code a bit.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-09-01 08:16:36 -04:00
Josef Bacik 57cfd46270 Btrfs: fix send to deal with sparse files properly
Send was just sending everything it found, even if the extent was a hole.  This
is unpleasant for users, so just skip holes when we are sending.  This will also
skip sending prealloc extents since the send spec doesn't have a prealloc
command.  Eventually we will add a prealloc command and rev the send version so
we can send down the prealloc info.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-09-01 08:16:21 -04:00
Stefan Behrens 35a3621beb Btrfs: get rid of sparse warnings
make C=2 fs/btrfs/ CF=-D__CHECK_ENDIAN__

I tried to filter out the warnings for which patches have already
been sent to the mailing list, pending for inclusion in btrfs-next.

All these changes should be obviously safe.

Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-09-01 08:15:50 -04:00
Josef Bacik ba5e8f2e2d Btrfs: fix send issues related to inode number reuse
If you are sending a snapshot and specifying a parent snapshot we will walk the
trees and figure out where they differ and send the differences only.  The way
we check for differences are if the leaves aren't the same and if the keys are
not the same within the leaves.  So if neither leaf is the same (ie the leaf has
been cow'ed from the parent snapshot) we walk each item in the send root and
check it against the parent root.  If the items match exactly then we don't do
anything.  This doesn't quite work for inode refs, since they will just have the
name and the parent objectid.  If you move the file from a directory and then
remove that directory and re-create a directory with the same inode number as
the old directory and then move that file back into that directory we will
assume that nothing changed and you will get errors when you try to receive.

In order to fix this we need to do extra checking to see if the inode ref really
is the same or not.  So do this by passing down BTRFS_COMPARE_TREE_SAME if the
items match.  Then if the key type is an inode ref we can do some extra
checking, otherwise we just keep processing.  The extra checking is to look up
the generation of the directory in the parent volume and compare it to the
generation of the send volume.  If they match then they are the same directory
and we are good to go.  If they don't we have to add them to the changed refs
list.

This means we have to track the generation of the ref we're trying to lookup
when we iterate all the refs for a particular inode.  So in the case of looking
for new refs we have to get the generation from the parent volume, and in the
case of looking for deleted refs we have to get the generation from the send
volume to compare with.

There was also the issue of using a ulist to keep track of the directories we
needed to check.  Because we can get a deleted ref and a new ref for the same
inode number the ulist won't work since it indexes based on the value.  So
instead just dup any directory ref we find and add it to a local list, and then
process that list as normal and do away with using a ulist for this altogether.

Before we would fail all of the tests in the far-progs that related to moving
directories (test group 32).  With this patch we now pass these tests, and all
of the tests in the far-progs send testing suite.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-09-01 08:15:44 -04:00
Josef Bacik a05254143c Btrfs: skip subvol entries when checking if we've created a dir already
We have logic to see if we've already created a parent directory by check to see
if an inode inside of that directory has a lower inode number than the one we
are currently processing.  The logic is that if there is a lower inode number
then we would have had to made sure the directory was created at that previous
point.  The problem is that subvols inode numbers count from the lowest objectid
in the root tree, which may be less than our current progress.  So just skip if
our dir item key is a root item.  This fixes the original test and the xfstest
version I made that added an extra subvol create.  Thanks,

Reported-by: Emil Karlson <jekarlson@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-09-01 08:05:01 -04:00
Josef Bacik ebdad913aa Btrfs: check our parent dir when doing a compare send
When doing a send with a parent subvol we will check to see if the file we are
acting on is being overwritten and move it if we think it may be needed further
down the line during the send.  We check this by checking its directory and
making sure it existed in the parent and making sure the file existed in the
parent.  The problem with this check is that if we create a directory and a file
in that directory, and then snapshot, and then remove and re-create that same
directory and file with different inode numbers and then try to snapshot and
send with the original parent we will try and save the original file inside of
that directory.  This is a problem because during the receive we move the
directory out of the way because it is a completely new inode, which makes us
unable to find the old file inside of the directory when we try to move that out
of the way for the overwrite.  We fix this by checking the parent directory of
the inode we think we are overwriting.  If the parent directory generation in
the send root != the parent directory generation in the parent root then we know
it is a completely new directory and we need not bother with moving the file out
of the way because it would have been completely destroyed.  This fixes bz
60673.  Thanks,

Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2013-09-01 08:04:48 -04:00
Joe Perches 8be04b9374 treewide: Add __GFP_NOWARN to k.alloc calls with v.alloc fallbacks
Don't emit OOM warnings when k.alloc calls fail when
there there is a v.alloc immediately afterwards.

Converted a kmalloc/vmalloc with memset to kzalloc/vzalloc.

Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2013-08-20 13:06:40 +02:00
Thomas Meyer a5959bc0a1 Btrfs: Cocci spatch "memdup.spatch"
Signed-off-by: Thomas Meyer <thomas@m3y3r.de>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-06-14 11:30:12 -04:00
Josef Bacik 139f807a1e Btrfs: fix estale with btrfs send
This fixes bugzilla 57491.  If we take a snapshot of a fs with a unlink ongoing
and then try to send that root we will run into problems.  When comparing with a
parent root we will search the parents and the send roots commit_root, which if
we've just created the snapshot will include the file that needs to be evicted
by the orphan cleanup.  So when we find a changed extent we will try and copy
that info into the send stream, but when we lookup the inode we use the normal
root, which no longer has the inode because the orphan cleanup deleted it.  The
best solution I have for this is to check our otransid with the generation of
the commit root and if they match just commit the transaction again, that way we
get the changes from the orphan cleanup.  With this patch the reproducer I made
for this bugzilla no longer returns ESTALE when trying to do the send.  Thanks,

Cc: stable@vger.kernel.org
Reported-by: Chris Wilson <jakdaw@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-06-14 11:29:55 -04:00
Stefan Behrens b1b195969f Btrfs: cleanup, btrfs_read_fs_root_no_name() doesn't return NULL
No need to check for NULL in send.c and disk-io.c.

Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-06-14 11:29:29 -04:00
Tsutomu Itoh 924794c936 Btrfs: cleanup unused arguments in send.c
sctx is removed from the argument of the function that
doesn't use sctx.

Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
2013-06-14 11:29:24 -04:00
Eric Sandeen 48a3b6366f btrfs: make static code static & remove dead code
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>
2013-05-06 15:55:23 -04:00
Tsutomu Itoh ecc7ada77b Btrfs: fix error handling in btrfs_ioctl_send()
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>
2013-05-06 15:55:13 -04:00
Tsutomu Itoh ba1eeaac99 Btrfs: remove unused variable in __process_changed_new_xattr()
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>
2013-05-06 15:55:12 -04:00
Stefan Behrens c2c71324ec Btrfs: allow omitting stream header and end-cmd for btrfs send
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>
2013-05-06 15:54:44 -04:00
Linus Torvalds 3615db41c4 Merge branch 'for-linus' of 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
2013-03-29 11:13:25 -07:00
Jan Schmidt adaa4b8e4d Btrfs: fix EIO from btrfs send in is_extent_unchanged for punched holes
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>
2013-03-28 09:51:26 -04:00
Linus Torvalds b695188dd3 Merge branch 'for-linus' of 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
  ...
2013-03-02 16:41:54 -08:00
Linus Torvalds d895cb1af1 Merge branch 'for-linus' of 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()
  ...
2013-02-26 20:16:07 -08:00
Al Viro 496ad9aa8e new helper: file_inode(file)
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-22 23:31:31 -05:00
Mark Fasheh cb95e7bf7b btrfs: add "no file data" flag to btrfs send ioctl
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>
2013-02-20 12:59:39 -05:00
Eric Sandeen b4c6f7b75c btrfs: remove unused fd in btrfs_ioctl_send()
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>
2013-02-20 12:59:14 -05:00
Tsutomu Itoh cfa7a9ccda Btrfs: fix memory leak in name_cache_insert()
We should free name_cache_entry before returning from the
error handling code.

Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
2013-01-14 13:52:30 -05:00
Anand Jain 5f3ab90a72 Btrfs: rename root_times_lock to root_item_lock
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>
2012-12-16 20:46:21 -05:00
Alex Lyakas e2d044fe77 Btrfs: Send: preserve ownership (uid and gid) also for symlinks.
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)) {
2012-10-25 15:47:31 -04:00
Arne Jansen d79e50433b Btrfs: send correct rdev and mode in btrfs-send
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>
2012-10-25 15:45:25 -04:00
Jan Schmidt 96b5bd7771 Btrfs: extended inode refs support for send mechanism
This adds support for the new extended inode refs to btrfs send.

Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
2012-10-25 15:45:16 -04:00
Anand Jain 1bcea35597 Btrfs: write_buf is now callable outside send.c
Developing service cmds needs it.

Signed-off-by: Anand Jain <anand.jain@oracle.com>
2012-10-04 09:39:55 -04:00
Liu Bo 69917e4312 Btrfs: fix a bug in parsing return value in logical resolve
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>
2012-10-01 15:19:18 -04:00
Jan Schmidt 995e01b7af Btrfs: fix gcc warnings for 32bit compiles
Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-10-01 15:19:01 -04:00
Chris Mason 74dd17fbe3 Btrfs: fix btrfs send for inline items and compression
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>
2012-10-01 15:19:00 -04:00
Alexander Block 6d85ed05e1 Btrfs: don't treat top/root directory inode as deleted/reused
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>
2012-10-01 15:19:00 -04:00
Alexander Block 2981e225f7 Btrfs: ignore non-FS inodes for send/receive
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>
2012-10-01 15:18:59 -04:00
Alexander Block 2f28f4787c Btrfs: pass root instead of parent_root to iterate_inode_ref
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>
2012-10-01 15:18:58 -04:00
Alexander Block d8347fa444 Btrfs: use <= instead of < in is_extent_unchanged
Used the wrong compare operator here.

Reported-by: Alex Lyakas <alex.bolshoy.btrfs@gmail.com>
Signed-off-by: Alexander Block <ablock84@googlemail.com>
2012-10-01 15:18:58 -04:00
Alexander Block 3954096d4b Btrfs: fix check for changed extent in is_extent_unchanged
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>
2012-10-01 15:18:57 -04:00
Alexander Block 5dc67d0ba9 Btrfs: free nce and nce_head on error in name_cache_insert
Both were leaked in case of error.

Reported-by: Alex Lyakas <alex.bolshoy.btrfs@gmail.com>
Signed-off-by: Alexander Block <ablock84@googlemail.com>
2012-10-01 15:18:56 -04:00
Alexander Block 3e126f32f8 Btrfs: remove unused tmp_path from iterate_dir_item
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>
2012-10-01 15:18:55 -04:00
Alexander Block e938c8ad54 Btrfs: code cleanups for send/receive
Doing some code cleanups as suggested by Arne.
Changes do not change any logic.

Signed-off-by: Alexander Block <ablock84@googlemail.com>
2012-10-01 15:18:55 -04:00
Alexander Block 766702ef49 Btrfs: add/fix comments/documentation for send/receive
As the subject already said, add/fix comments.

Signed-off-by: Alexander Block <ablock84@googlemail.com>
2012-10-01 15:18:54 -04:00
Alexander Block e479d9bb5f Btrfs: update send_progress at correct places
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>
2012-10-01 15:18:53 -04:00
Alexander Block 7e0926fe5f Btrfs: fix use of radix_tree for name_cache in send/receive
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>
2012-10-01 15:18:52 -04:00
Alexander Block 17589bd96e Btrfs: fix memory leak for name_cache in send/receive
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>
2012-10-01 15:18:51 -04:00
Alexander Block adbe7fb6c4 Btrfs: don't break in the final loop of find_extent_clone
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>
2012-10-01 15:18:50 -04:00
Alexander Block 52f9e53ede Btrfs: use normal return path for root == send_root case
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>
2012-10-01 15:18:50 -04:00
Alexander Block 35075bb046 Btrfs: use kmalloc instead of stack for backref_ctx
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>
2012-10-01 15:18:49 -04:00
Alexander Block ee849c0472 Btrfs: rename backref_ctx::found_in_send_root to found_itself
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>
2012-10-01 15:18:48 -04:00
Alexander Block d27aed5e24 Btrfs: remove unused use_list from send/receive code
use_list is a leftover and unused.

Signed-off-by: Alexander Block <ablock84@googlemail.com>
2012-10-01 15:18:48 -04:00
Alexander Block ccf1626b49 Btrfs: add correct parent to check_dirs when dir got moved
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>
2012-10-01 15:18:47 -04:00
Alexander Block 9ea3ef516d Btrfs: remove unused code with #if 0
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>
2012-10-01 15:18:46 -04:00
Alexander Block b9291affaa Btrfs: add missing check for dir != tmp_dir to is_first_ref
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>
2012-10-01 15:18:45 -04:00
Alexander Block 1f4692da95 Btrfs: fix cur_ino < parent_ino case for send/receive
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>
2012-10-01 15:18:45 -04:00
Alexander Block 85a7b33b96 Btrfs: add rdev to get_inode_info in send/receive
We need rdev in the next commit.

Signed-off-by: Alexander Block <ablock84@googlemail.com>
2012-10-01 15:18:44 -04:00
Stephen Rothwell a1857ebe75 Btrfs: using vmalloc and friends needs vmalloc.h
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>
2012-07-26 18:08:30 -07:00
Linus Torvalds e2aed8dfa5 Merge branch 'for-linus' of 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 765927b2d5 ("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
2012-07-26 14:48:55 -07:00
Chris Mason b24baf6917 Btrfs: uninit variable fixes in send/receive
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
2012-07-25 19:21:10 -04:00
Alexander Block 31db9f7c23 Btrfs: introduce BTRFS_IOC_SEND for btrfs send/receive
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>
2012-07-25 23:30:19 +02:00