1. 10 12月, 2008 1 次提交
    • C
      Btrfs: Delete csum items when freeing extents · 459931ec
      Chris Mason 提交于
      This finishes off the new checksumming code by removing csum items
      for extents that are no longer in use.
      
      The trick is doing it without racing because a single csum item may
      hold csums for more than one extent.  Extra checks are added to
      btrfs_csum_file_blocks to make sure that we are using the correct
      csum item after dropping locks.
      
      A new btrfs_split_item is added to split a single csum item so it
      can be split without dropping the leaf lock.  This is used to
      remove csum bytes from the middle of an item.
      Signed-off-by: NChris Mason <chris.mason@oracle.com>
      459931ec
  2. 09 12月, 2008 5 次提交
    • C
      Btrfs: Fix compressed checksum fsync log copies · 580afd76
      Chris Mason 提交于
      The fsync logging code makes sure to onl copy the relevant checksum for each
      extent based on the file extent pointers it finds.
      
      But for compressed extents, it needs to copy the checksum for the
      entire extent.
      Signed-off-by: NChris Mason <chris.mason@oracle.com>
      580afd76
    • C
      Btrfs: Add inode sequence number for NFS and reserved space in a few structs · c3027eb5
      Chris Mason 提交于
      This adds a sequence number to the btrfs inode that is increased on
      every update.  NFS will be able to use that to detect when an inode has
      changed, without relying on inaccurate time fields.
      
      While we're here, this also:
      
      Puts reserved space into the super block and inode
      
      Adds a log root transid to the super so we can pick the newest super
      based on the fsync log as well as the main transaction ID.  For now
      the log root transid is always zero, but that'll get fixed.
      
      Adds a starting offset to the dev_item.  This will let us do better
      alignment calculations if we know the start of a partition on the disk.
      Signed-off-by: NChris Mason <chris.mason@oracle.com>
      c3027eb5
    • C
      Btrfs: Use map_private_extent_buffer during generic_bin_search · 934d375b
      Chris Mason 提交于
      It is possible that generic_bin_search will be called on a tree block
      that has not been locked.  This happens because cache_block_block skips
      locking on the tree blocks.
      
      Since the tree block isn't locked, we aren't allowed to change
      the extent_buffer->map_token field.  Using map_private_extent_buffer
      avoids any changes to the internal extent buffer fields.
      Signed-off-by: NChris Mason <chris.mason@oracle.com>
      934d375b
    • Y
      Btrfs: superblock duplication · a512bbf8
      Yan Zheng 提交于
      This patch implements superblock duplication. Superblocks
      are stored at offset 16K, 64M and 256G on every devices.
      Spaces used by superblocks are preserved by the allocator,
      which uses a reverse mapping function to find the logical
      addresses that correspond to superblocks. Thank you,
      Signed-off-by: NYan Zheng <zheng.yan@oracle.com>
      a512bbf8
    • C
      Btrfs: move data checksumming into a dedicated tree · d20f7043
      Chris Mason 提交于
      Btrfs stores checksums for each data block.  Until now, they have
      been stored in the subvolume trees, indexed by the inode that is
      referencing the data block.  This means that when we read the inode,
      we've probably read in at least some checksums as well.
      
      But, this has a few problems:
      
      * The checksums are indexed by logical offset in the file.  When
      compression is on, this means we have to do the expensive checksumming
      on the uncompressed data.  It would be faster if we could checksum
      the compressed data instead.
      
      * If we implement encryption, we'll be checksumming the plain text and
      storing that on disk.  This is significantly less secure.
      
      * For either compression or encryption, we have to get the plain text
      back before we can verify the checksum as correct.  This makes the raid
      layer balancing and extent moving much more expensive.
      
      * It makes the front end caching code more complex, as we have touch
      the subvolume and inodes as we cache extents.
      
      * There is potentitally one copy of the checksum in each subvolume
      referencing an extent.
      
      The solution used here is to store the extent checksums in a dedicated
      tree.  This allows us to index the checksums by phyiscal extent
      start and length.  It means:
      
      * The checksum is against the data stored on disk, after any compression
      or encryption is done.
      
      * The checksum is stored in a central location, and can be verified without
      following back references, or reading inodes.
      
      This makes compression significantly faster by reducing the amount of
      data that needs to be checksummed.  It will also allow much faster
      raid management code in general.
      
      The checksums are indexed by a key with a fixed objectid (a magic value
      in ctree.h) and offset set to the starting byte of the extent.  This
      allows us to copy the checksum items into the fsync log tree directly (or
      any other tree), without having to invent a second format for them.
      Signed-off-by: NChris Mason <chris.mason@oracle.com>
      d20f7043
  3. 03 12月, 2008 1 次提交
  4. 02 12月, 2008 14 次提交
  5. 21 11月, 2008 1 次提交
  6. 20 11月, 2008 10 次提交
    • C
      Btrfs: only flush down bios for writeback pages · 0e6bd956
      Chris Mason 提交于
      The btrfs write_cache_pages call has a flush function so that it submits
      the bio it has been building before it waits on any writeback pages.
      
      This adds a check so that flush only happens on writeback pages.
      Signed-off-by: NChris Mason <chris.mason@oracle.com>
      0e6bd956
    • L
      Btrfs: Fix cow semantic in run_delalloc_nocow() · 43dd729b
      Liu Hui 提交于
      The file preallocation code reversed the logic to force nodatacow.  This
      fixes it.
      43dd729b
    • Y
      Btrfs: Drop dirty roots created by log replay immediately when · e556ce2c
      Yan Zheng 提交于
      The log replay produces dirty roots. These dirty roots
      should be dropped immediately if the fs is mounted as
      ro. Otherwise they can be added to the dirty root list
      again when remounting the fs as rw. Thank you,
      Signed-off-by: NYan Zheng <zheng.yan@oracle.com>
      e556ce2c
    • C
      Btrfs: compat code fixes · 4b4e25f2
      Chris Mason 提交于
      The btrfs git kernel trees is used to build a standalone tree for
      compiling against older kernels.  This commit makes the standalone tree
      work with 2.6.27
      Signed-off-by: NChris Mason <chris.mason@oracle.com>
      4b4e25f2
    • C
      Btrfs: Use current_fsuid/gid · 79683f2d
      Chris Mason 提交于
      This fixes compile problems with linux-next
      Signed-off-by: NChris Mason <chris.mason@oracle.com>
      79683f2d
    • C
      Btrfs: Fixes for 2.6.28-rc API changes · 15916de8
      Chris Mason 提交于
      * open/close_bdev_excl -> open/close_bdev_exclusive
      * blkdev_issue_discard takes a GFP mask now
      * Fix blkdev_issue_discard usage now that it is enabled
      Signed-off-by: NChris Mason <chris.mason@oracle.com>
      15916de8
    • C
    • J
      Btrfs: fix free space accounting when unpinning extents · 07103a3c
      Josef Bacik 提交于
      This patch fixes what I hope is the last early ENOSPC bug left.  I did not know
      that pinned extents would merge into one big extent when inserted on to the
      pinned extent tree, so I was adding free space to a block group that could
      possibly span multiple block groups.
      
      This is a big issue because first that space doesn't exist in that block group,
      and second we won't actually use that space because there are a bunch of other
      checks to make sure we're allocating within the constraints of the block group.
      
      This patch fixes the problem by adding the btrfs_add_free_space to
      btrfs_update_pinned_extents which makes sure we are adding the appropriate
      amount of free space to the appropriate block group.  Thanks much to Lee Trager
      for running my myriad of debug patches to help me track this problem down.
      Thank you,
      Signed-off-by: NJosef Bacik <jbacik@redhat.com>
      07103a3c
    • C
      Btrfs: Do fsync log replay when mount -o ro, except when on readonly media · 7c2ca468
      Chris Mason 提交于
      fsync log replay can change the filesystem, so it cannot be delayed until
      mount -o rw,remount, and it can't be forgotten entirely.  So, this patch
      changes btrfs to do with reiserfs, ext3 and xfs do, which is to do the
      log replay even when mounted readonly.
      
      On a readonly device if log replay is required, the mount is aborted.
      
      Getting all of this right had required fixing up some of the error
      handling in open_ctree.
      Signed-off-by: NChris Mason <chris.mason@oracle.com>
      7c2ca468
    • C
      Btrfs: Avoid writeback stalls · d2c3f4f6
      Chris Mason 提交于
      While building large bios in writepages, btrfs may end up waiting
      for other page writeback to finish if WB_SYNC_ALL is used.
      
      While it is waiting, the bio it is building has a number of pages with the
      writeback bit set and they aren't getting to the disk any time soon.  This
      lowers the latencies of writeback in general by sending down the bio being
      built before waiting for other pages.
      
      The bio submission code tries to limit the total number of async bios in
      flight by waiting when we're over a certain number of async bios.  But,
      the waits are happening while writepages is building bios, and this can easily
      lead to stalls and other problems for people calling wait_on_page_writeback.
      
      The current fix is to let the congestion tests take care of waiting.
      
      sync() and others make sure to drain the current async requests to make
      sure that everything that was pending when the sync was started really get
      to disk.  The code would drain pending requests both before and after
      submitting a new request.
      
      But, if one of the requests is waiting for page writeback to finish,
      the draining waits might block that page writeback.  This changes the
      draining code to only wait after submitting the bio being processed.
      Signed-off-by: NChris Mason <chris.mason@oracle.com>
      d2c3f4f6
  7. 19 11月, 2008 2 次提交
  8. 18 11月, 2008 1 次提交
  9. 19 11月, 2008 1 次提交
    • L
      Btrfs: Some fixes for batching extent insert. · b4eec2ca
      Liu Hui 提交于
      In insert_extents(), when ret==1 and last is not zero, it should
      check if the current inserted item is the last item in this batching
      inserts. If so, it should just break from loop. If not, 'cur =
      insert_list->next' will make no sense because the list is empty now,
      and 'op' will point to an unexpectable place.
      
      There are also some trivial fixs in this patch including one comment
      typo error and deleting two redundant lines.
      Signed-off-by: NChris Mason <chris.mason@oracle.com>
      b4eec2ca
  10. 18 11月, 2008 4 次提交
    • C
      Btrfs: prevent loops in the directory tree when creating snapshots · ea9e8b11
      Chris Mason 提交于
      For a directory tree:
      
      /mnt/subvolA/subvolB
      
      btrfsctl -s /mnt/subvolA/subvolB /mnt
      
      Will create a directory loop with subvolA under subvolB.  This
      commit uses the forward refs for each subvol and snapshot to error out
      before creating the loop.
      Signed-off-by: NChris Mason <chris.mason@oracle.com>
      ea9e8b11
    • C
      Btrfs: Add backrefs and forward refs for subvols and snapshots · 0660b5af
      Chris Mason 提交于
      Subvols and snapshots can now be referenced from any point in the directory
      tree.  We need to maintain back refs for them so we can find lost
      subvols.
      
      Forward refs are added so that we know all of the subvols and
      snapshots referenced anywhere in the directory tree of a single subvol.  This
      can be used to do recursive snapshotting (but they aren't yet) and it is
      also used to detect and prevent directory loops when creating new snapshots.
      Signed-off-by: NChris Mason <chris.mason@oracle.com>
      0660b5af
    • C
      Btrfs: Give each subvol and snapshot their own anonymous devid · 3394e160
      Chris Mason 提交于
      Each subvolume has its own private inode number space, and so we need
      to fill in different device numbers for each subvolume to avoid confusing
      applications.
      
      This commit puts a struct super_block into struct btrfs_root so it can
      call set_anon_super() and get a different device number generated for
      each root.
      
      btrfs_rename is changed to prevent renames across subvols.
      Signed-off-by: NChris Mason <chris.mason@oracle.com>
      3394e160
    • C
      Btrfs: Allow subvolumes and snapshots anywhere in the directory tree · 3de4586c
      Chris Mason 提交于
      Before, all snapshots and subvolumes lived in a single flat directory.  This
      was awkward and confusing because the single flat directory was only writable
      with the ioctls.
      
      This commit changes the ioctls to create subvols and snapshots at any
      point in the directory tree.  This requires making separate ioctls for
      snapshot and subvol creation instead of a combining them into one.
      
      The subvol ioctl does:
      
      btrfsctl -S subvol_name parent_dir
      
      After the ioctl is done subvol_name lives inside parent_dir.
      
      The snapshot ioctl does:
      
      btrfsctl -s path_for_snapshot root_to_snapshot
      
      path_for_snapshot can be an absolute or relative path.  btrfsctl breaks it up
      into directory and basename components.
      
      root_to_snapshot can be any file or directory in the FS.  The snapshot
      is taken of the entire root where that file lives.
      Signed-off-by: NChris Mason <chris.mason@oracle.com>
      3de4586c