1. 04 Mar, 2013 9 commits
  2. 03 Mar, 2013 1 commit
  3. 01 Mar, 2013 8 commits
  4. 28 Feb, 2013 8 commits
  5. 26 Feb, 2013 6 commits
    • Qu Wenruo's avatar
      btrfs: cleanup for open-coded alignment · fda2832f
      Qu Wenruo authored
      Though most of the btrfs codes are using ALIGN macro for page alignment,
      there are still some codes using open-coded alignment like the
      following:
      ------
              u64 mask = ((u64)root->stripesize - 1);
              u64 ret = (val + mask) & ~mask;
      ------
      Or even hidden one:
      ------
              num_bytes = (end - start + blocksize) & ~(blocksize - 1);
      ------
      
      Sometimes these open-coded alignment is not so easy to understand for
      newbie like me.
      
      This commit changes the open-coded alignment to the ALIGN macro for a
      better readability.
      
      Also there is a previous patch from David Sterba with similar changes,
      but the patch is for 3.2 kernel and seems not merged.
      http://www.spinics.net/lists/linux-btrfs/msg12747.html
      
      Cc: David Sterba <dave@jikos.cz>
      Signed-off-by: default avatarQu Wenruo <quwenruo@cn.fujitsu.com>
      Signed-off-by: default avatarJosef Bacik <jbacik@fusionio.com>
      fda2832f
    • Liu Bo's avatar
      Btrfs: do not change inode flags in rename · 8c4ce81e
      Liu Bo authored
      Before we forced to change a file's NOCOW and COMPRESS flag due to
      the parent directory's, but this ends up a bad idea, because it
      confuses end users a lot about file's NOCOW status, eg. if someone
      change a file to NOCOW via 'chattr' and then rename it in the current
      directory which is without NOCOW attribute, the file will lose the
      NOCOW flag silently.
      
      This diables 'change flags in rename', so from now on we'll only
      inherit flags from the parent directory on creation stage while in
      other places we can use 'chattr' to set NOCOW or COMPRESS flags.
      Reported-by: default avatarMarios Titas <redneb8888@gmail.com>
      Signed-off-by: default avatarLiu Bo <bo.li.liu@oracle.com>
      Reviewed-by: default avatarDavid Sterba <dsterba@suse.cz>
      Signed-off-by: default avatarJosef Bacik <jbacik@fusionio.com>
      8c4ce81e
    • Liu Bo's avatar
      Btrfs: use reserved space for creating a snapshot · 2382c5cc
      Liu Bo authored
      While inserting dir index and updating inode for a snapshot, we'd
      add delayed items which consume trans->block_rsv, if we don't have
      any space reserved in this trans handle, we either just return or
      reserve space again.
      
      But before creating pending snapshots during committing transaction,
      we've done a release on this trans handle, so we don't have space reserved
      in it at this stage.
      
      What we're using is block_rsv of pending snapshots which has already
      reserved well enough space for both inserting dir index and updating
      inode, so we need to set trans handle to indicate that we have space
      now.
      Signed-off-by: default avatarLiu Bo <bo.li.liu@oracle.com>
      Reviewed-by: default avatarMiao Xie <miaox@cn.fujitsu.com>
      Signed-off-by: default avatarJosef Bacik <jbacik@fusionio.com>
      2382c5cc
    • Alexandre Oliva's avatar
      clear chunk_alloc flag on retryable failure · a81cb9a2
      Alexandre Oliva authored
      I've experienced filesystem freezes with permanent spikes in the active
      process count for quite a while, particularly on filesystems whose
      available raw space has already been fully allocated to chunks.
      
      While looking into this, I found a pretty obvious error in
      do_chunk_alloc: it sets space_info->chunk_alloc, but if
      btrfs_alloc_chunk returns an error other than ENOSPC, it returns leaving
      that flag set, which causes any other threads waiting for
      space_info->chunk_alloc to become zero to spin indefinitely.
      
      I haven't double-checked that this patch fixes the failure I've observed
      fully (it's not exactly trivial to trigger), but it surely is a bug and
      the fix is trivial, so...  Please put it in :-)
      
      What I saw in that function also happens to explain why in some cases I
      see filesystems allocate a huge number of chunks that remain unused
      (leading to the scenario above, of not having more chunks to allocate).
      It happens for data and metadata, but not necessarily both.  I'm
      guessing some thread sets the force_alloc flag on the corresponding
      space_info, and then several threads trying to get disk space end up
      attempting to allocate a new chunk concurrently.  All of them will see
      the force_alloc flag and bump their local copy of force up to the level
      they see first, and they won't clear it even if another thread succeeds
      in allocating a chunk, thus clearing the force flag.  Then each thread
      that observed the force flag will, on its turn, force the allocation of
      a new chunk.  And any threads that come in while it does that will see
      the force flag still set and pick it up, and so on.  This sounds like a
      problem to me, but...  what should the correct behavior be?  Clear
      force_flag once we copy it to a local force?  Reset force to the
      incoming value on every loop?  Set the flag to our incoming force if we
      have it at first, clear our local flag, and move it from the space_info
      when we determined that we are the thread that's going to perform the
      allocation?
      
      btrfs: clear chunk_alloc flag on retryable failure
      
      From: Alexandre Oliva <oliva@gnu.org>
      
      If btrfs_alloc_chunk fails with e.g. ENOMEM, we exit do_chunk_alloc
      without clearing chunk_alloc in space_info.  As a result, any further
      calls to do_chunk_alloc on that filesystem will start busy-waiting for
      chunk_alloc to be cleared, but it never will be.  This patch adjusts
      do_chunk_alloc so that it clears this flag in case of an error.
      Signed-off-by: default avatarAlexandre Oliva <oliva@gnu.org>
      Signed-off-by: default avatarJosef Bacik <jbacik@fusionio.com>
      a81cb9a2
    • Jan Schmidt's avatar
      Btrfs: fix backref walking race with tree deletions · ca60ebfa
      Jan Schmidt authored
      When a subvolume is removed, we remove the root item from the root tree,
      while the tree blocks and backrefs remain for a while. When backref walking
      comes across one of those orphan tree blocks, it can find a backref for a
      no longer existing root. This is all good, we only must tolerate
      __resolve_indirect_ref returning an error and continue with the good refs
      found.
      Reported-by: default avatarAlex Lyakas <alex.btrfs@zadarastorage.com>
      Signed-off-by: default avatarJan Schmidt <list.btrfs@jan-o-sch.net>
      Signed-off-by: default avatarJosef Bacik <jbacik@fusionio.com>
      ca60ebfa
    • Josef Bacik's avatar
      Btrfs: make sure NODATACOW also gets NODATASUM set · f2bdf9a8
      Josef Bacik authored
      A user reported hitting the BUG_ON() in btrfs_finished_ordered_io() where we had
      csums on a NOCOW extent.  This can happen if we have NODATACOW set but not
      NODATASUM set, which can happen in two cases, either we mount with -o nodatacow
      and then write into preallocated space, or chattr +C a directory and move a file
      into that directory.  Liu has fixed the move case in a different place, but this
      fixes the mount -o nodatacow case.  Thanks,
      Signed-off-by: default avatarJosef Bacik <jbacik@fusionio.com>
      f2bdf9a8
  6. 21 Feb, 2013 2 commits
    • Miao Xie's avatar
      Btrfs: fix remount vs autodefrag · dc81cdc5
      Miao Xie authored
      If we remount the fs to close the auto defragment or make the fs R/O,
      we should stop the auto defragment.
      Signed-off-by: default avatarMiao Xie <miaox@cn.fujitsu.com>
      Signed-off-by: default avatarChris Mason <chris.mason@fusionio.com>
      dc81cdc5
    • Miao Xie's avatar
      Btrfs: fix wrong outstanding_extents when doing DIO write · 172a5049
      Miao Xie authored
      When running the 083th case of xfstests on the filesystem with
      "compress-force=lzo", the following WARNINGs were triggered.
        WARNING: at fs/btrfs/inode.c:7908
        WARNING: at fs/btrfs/inode.c:7909
        WARNING: at fs/btrfs/inode.c:7911
        WARNING: at fs/btrfs/extent-tree.c:4510
        WARNING: at fs/btrfs/extent-tree.c:4511
      
      This problem was introduced by the patch "Btrfs: fix deadlock due
      to unsubmitted". In this patch, there are two bugs which caused
      the above problem.
      
      The 1st one is a off-by-one bug, if the DIO write return 0, it is
      also a short write, we need release the reserved space for it. But
      we didn't do it in that patch. Fix it by change "ret > 0" to
      "ret >= 0".
      
      The 2nd one is ->outstanding_extents was increased twice when
      a short write happened. As we know, ->outstanding_extents is
      a counter to keep track of the number of extent items we may
      use duo to delalloc, when we reserve the free space for a
      delalloc write, we assume that the write will introduce just
      one extent item, so we increase ->outstanding_extents by 1 at
      that time. And then we will increase it every time we split the
      write, it is done at the beginning of btrfs_get_blocks_direct().
      So when a short write happens, we needn't increase
      ->outstanding_extents again. But this patch done.
      
      In order to fix the 2nd problem, I re-write the logic for
      ->outstanding_extents operation. We don't increase it at the
      beginning of btrfs_get_blocks_direct(), instead, we just
      increase it when the split actually happens.
      Reported-by: default avatarMitch Harder <mitch.harder@sabayonlinux.org>
      Signed-off-by: default avatarMiao Xie <miaox@cn.fujitsu.com>
      Signed-off-by: default avatarChris Mason <chris.mason@fusionio.com>
      172a5049
  7. 20 Feb, 2013 6 commits
    • Liu Bo's avatar
      Btrfs: snapshot-aware defrag · 38c227d8
      Liu Bo authored
      This comes from one of btrfs's project ideas,
      As we defragment files, we break any sharing from other snapshots.
      The balancing code will preserve the sharing, and defrag needs to grow this
      as well.
      
      Now we're able to fill the blank with this patch, in which we make full use of
      backref walking stuff.
      
      Here is the basic idea,
      o  set the writeback ranges started by defragment with flag EXTENT_DEFRAG
      o  at endio, after we finish updating fs tree, we use backref walking to find
         all parents of the ranges and re-link them with the new COWed file layout by
         adding corresponding backrefs.
      Signed-off-by: default avatarLi Zefan <lizf@cn.fujitsu.com>
      Signed-off-by: default avatarLiu Bo <bo.li.liu@oracle.com>
      Signed-off-by: default avatarChris Mason <chris.mason@fusionio.com>
      38c227d8
    • Chris Mason's avatar
      Btrfs: fix max chunk size on raid5/6 · 86db2578
      Chris Mason authored
      We try to limit the size of a chunk to 10GB, which keeps the unit of
      work reasonable during balance and resize operations.  The limit checks
      were taking into account the number of copies of the data we had but
      what they really should be doing is comparing against the logical
      size of the chunk we're creating.
      
      This moves the code around a little to use the count of data stripes
      from raid5/6.
      Signed-off-by: default avatarChris Mason <chris.mason@fusionio.com>
      86db2578
    • Zach Brown's avatar
      btrfs: limit fallocate extent reservation to 256MB · 24542bf7
      Zach Brown authored
      Very large fallocate requests are cpu bound and result in extents with a
      repeating pattern of ever decreasing size:
      
      $ time fallocate -l 1T file
      real	0m13.039s
      
      ( an excerpt of the extents from btrfs-debug-tree: )
        prealloc data disk byte 1536292564992 nr 397312
        prealloc data disk byte 1536292962304 nr 196608
        prealloc data disk byte 1536293158912 nr 98304
        prealloc data disk byte 1536293257216 nr 49152
        prealloc data disk byte 1536293306368 nr 24576
        prealloc data disk byte 1536293330944 nr 12288
        prealloc data disk byte 1536293343232 nr 8192
        prealloc data disk byte 1536293351424 nr 4096
        prealloc data disk byte 1536293355520 nr 4096
        prealloc data disk byte 1536293359616 nr 4096
      
      The excessive cpu use comes from __btrfs_prealloc_file_range() trying to
      allocate the entire remaining size after each extent is allocated.
      btrfs_reserve_extent() repeatedly cuts this requested size in half until
      it gets down to the size that the allocators can return.  We limit the
      problem for now by capping each reservation at 256 meg.
      
      The small extents come from a masking bug when decreasing the requested
      reservation size.  The high 32bits are cleared and the remaining low
      bits might happen to reserve a small size.   Fix this by using
      round_down() which properly casts the mask.
      
      After these fixes huge fallocate requests are fast and result in nice
      large extents:
      
      $ time fallocate -l 1T file
      real	0m0.082s
      
        prealloc data disk byte 1112425889792 nr 268435456
        prealloc data disk byte 1112694325248 nr 268435456
        prealloc data disk byte 1112962760704 nr 268435456
      Reported-by: default avatarEric Sandeen <sandeen@redhat.com>
      Signed-off-by: default avatarZach Brown <zab@redhat.com>
      Signed-off-by: default avatarChris Mason <chris.mason@fusionio.com>
      24542bf7
    • Thomas Gleixner's avatar
      btrfs: Init io_lock after cloning btrfs device struct · 1cba0cdf
      Thomas Gleixner authored
      __btrfs_close_devices() clones btrfs device structs with
      memcpy(). Some of the fields in the clone are reinitialized, but it's
      missing to init io_lock. In mainline this goes unnoticed, but on RT it
      leaves the plist pointing to the original about to be freed lock
      struct.
      
      Initialize io_lock after cloning, so no references to the original
      struct are left.
      Reported-and-tested-by: default avatarMike Galbraith <efault@gmx.de>
      Cc: stable@vger.kernel.org
      Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
      Signed-off-by: default avatarChris Mason <chris.mason@fusionio.com>
      1cba0cdf
    • Chris Mason's avatar
      Merge branch 'raid56-experimental' into for-linus-3.9 · e942f883
      Chris Mason authored
      Signed-off-by: default avatarChris Mason <chris.mason@fusionio.com>
      
      Conflicts:
      	fs/btrfs/ctree.h
      	fs/btrfs/extent-tree.c
      	fs/btrfs/inode.c
      	fs/btrfs/volumes.c
      e942f883
    • Chris Mason's avatar
      Merge branch 'master' of... · b2c6b3e0
      Chris Mason authored
      Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/josef/btrfs-next into for-linus-3.9
      Signed-off-by: default avatarChris Mason <chris.mason@fusionio.com>
      
      Conflicts:
      	fs/btrfs/disk-io.c
      b2c6b3e0