1. 29 10月, 2010 1 次提交
    • J
      Btrfs: create special free space cache inode · 0af3d00b
      Josef Bacik 提交于
      In order to save free space cache, we need an inode to hold the data, and we
      need a special item to point at the right inode for the right block group.  So
      first, create a special item that will point to the right inode, and the number
      of extent entries we will have and the number of bitmaps we will have.  We
      truncate and pre-allocate space everytime to make sure it's uptodate.
      
      This feature will be turned on as soon as you mount with -o space_cache, however
      it is safe to boot into old kernels, they will just generate the cache the old
      fashion way.  When you boot back into a newer kernel we will notice that we
      modified and not the cache and automatically discard the cache.
      Signed-off-by: NJosef Bacik <josef@redhat.com>
      0af3d00b
  2. 10 8月, 2010 1 次提交
    • A
      convert btrfs to ->evict_inode() · bd555975
      Al Viro 提交于
      NB: do we want btrfs_wait_ordered_range() on eviction of
      inodes with positive i_nlink on subvolume with zero root_refs?
      If not, btrfs_evict_inode() can be simplified by unconditionally
      bailing out in case of i_nlink > 0 in the very beginning...
      Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
      bd555975
  3. 12 6月, 2010 2 次提交
  4. 26 5月, 2010 1 次提交
    • K
      driver core: add devname module aliases to allow module on-demand auto-loading · 578454ff
      Kay Sievers 提交于
      This adds:
        alias: devname:<name>
      to some common kernel modules, which will allow the on-demand loading
      of the kernel module when the device node is accessed.
      
      Ideally all these modules would be compiled-in, but distros seems too
      much in love with their modularization that we need to cover the common
      cases with this new facility. It will allow us to remove a bunch of pretty
      useless init scripts and modprobes from init scripts.
      
      The static device node aliases will be carried in the module itself. The
      program depmod will extract this information to a file in the module directory:
        $ cat /lib/modules/2.6.34-00650-g537b60d1-dirty/modules.devname
        # Device nodes to trigger on-demand module loading.
        microcode cpu/microcode c10:184
        fuse fuse c10:229
        ppp_generic ppp c108:0
        tun net/tun c10:200
        dm_mod mapper/control c10:235
      
      Udev will pick up the depmod created file on startup and create all the
      static device nodes which the kernel modules specify, so that these modules
      get automatically loaded when the device node is accessed:
        $ /sbin/udevd --debug
        ...
        static_dev_create_from_modules: mknod '/dev/cpu/microcode' c10:184
        static_dev_create_from_modules: mknod '/dev/fuse' c10:229
        static_dev_create_from_modules: mknod '/dev/ppp' c108:0
        static_dev_create_from_modules: mknod '/dev/net/tun' c10:200
        static_dev_create_from_modules: mknod '/dev/mapper/control' c10:235
        udev_rules_apply_static_dev_perms: chmod '/dev/net/tun' 0666
        udev_rules_apply_static_dev_perms: chmod '/dev/fuse' 0666
      
      A few device nodes are switched to statically allocated numbers, to allow
      the static nodes to work. This might also useful for systems which still run
      a plain static /dev, which is completely unsafe to use with any dynamic minor
      numbers.
      
      Note:
      The devname aliases must be limited to the *common* and *single*instance*
      device nodes, like the misc devices, and never be used for conceptually limited
      systems like the loop devices, which should rather get fixed properly and get a
      control node for losetup to talk to, instead of creating a random number of
      device nodes in advance, regardless if they are ever used.
      
      This facility is to hide the mess distros are creating with too modualized
      kernels, and just to hide that these modules are not compiled-in, and not to
      paper-over broken concepts. Thanks! :)
      
      Cc: Greg Kroah-Hartman <gregkh@suse.de>
      Cc: David S. Miller <davem@davemloft.net>
      Cc: Miklos Szeredi <miklos@szeredi.hu>
      Cc: Chris Mason <chris.mason@oracle.com>
      Cc: Alasdair G Kergon <agk@redhat.com>
      Cc: Tigran Aivazian <tigran@aivazian.fsnet.co.uk>
      Cc: Ian Kent <raven@themaw.net>
      Signed-Off-By: NKay Sievers <kay.sievers@vrfy.org>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
      578454ff
  5. 25 5月, 2010 3 次提交
  6. 31 3月, 2010 1 次提交
  7. 30 3月, 2010 1 次提交
    • T
      include cleanup: Update gfp.h and slab.h includes to prepare for breaking... · 5a0e3ad6
      Tejun Heo 提交于
      include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
      
      percpu.h is included by sched.h and module.h and thus ends up being
      included when building most .c files.  percpu.h includes slab.h which
      in turn includes gfp.h making everything defined by the two files
      universally available and complicating inclusion dependencies.
      
      percpu.h -> slab.h dependency is about to be removed.  Prepare for
      this change by updating users of gfp and slab facilities include those
      headers directly instead of assuming availability.  As this conversion
      needs to touch large number of source files, the following script is
      used as the basis of conversion.
      
        http://userweb.kernel.org/~tj/misc/slabh-sweep.py
      
      The script does the followings.
      
      * Scan files for gfp and slab usages and update includes such that
        only the necessary includes are there.  ie. if only gfp is used,
        gfp.h, if slab is used, slab.h.
      
      * When the script inserts a new include, it looks at the include
        blocks and try to put the new include such that its order conforms
        to its surrounding.  It's put in the include block which contains
        core kernel includes, in the same order that the rest are ordered -
        alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
        doesn't seem to be any matching order.
      
      * If the script can't find a place to put a new include (mostly
        because the file doesn't have fitting include block), it prints out
        an error message indicating which .h file needs to be added to the
        file.
      
      The conversion was done in the following steps.
      
      1. The initial automatic conversion of all .c files updated slightly
         over 4000 files, deleting around 700 includes and adding ~480 gfp.h
         and ~3000 slab.h inclusions.  The script emitted errors for ~400
         files.
      
      2. Each error was manually checked.  Some didn't need the inclusion,
         some needed manual addition while adding it to implementation .h or
         embedding .c file was more appropriate for others.  This step added
         inclusions to around 150 files.
      
      3. The script was run again and the output was compared to the edits
         from #2 to make sure no file was left behind.
      
      4. Several build tests were done and a couple of problems were fixed.
         e.g. lib/decompress_*.c used malloc/free() wrappers around slab
         APIs requiring slab.h to be added manually.
      
      5. The script was run on all .h files but without automatically
         editing them as sprinkling gfp.h and slab.h inclusions around .h
         files could easily lead to inclusion dependency hell.  Most gfp.h
         inclusion directives were ignored as stuff from gfp.h was usually
         wildly available and often used in preprocessor macros.  Each
         slab.h inclusion directive was examined and added manually as
         necessary.
      
      6. percpu.h was updated not to include slab.h.
      
      7. Build test were done on the following configurations and failures
         were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
         distributed build env didn't work with gcov compiles) and a few
         more options had to be turned off depending on archs to make things
         build (like ipr on powerpc/64 which failed due to missing writeq).
      
         * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
         * powerpc and powerpc64 SMP allmodconfig
         * sparc and sparc64 SMP allmodconfig
         * ia64 SMP allmodconfig
         * s390 SMP allmodconfig
         * alpha SMP allmodconfig
         * um on x86_64 SMP allmodconfig
      
      8. percpu.h modifications were reverted so that it could be applied as
         a separate patch and serve as bisection point.
      
      Given the fact that I had only a couple of failures from tests on step
      6, I'm fairly confident about the coverage of this conversion patch.
      If there is a breakage, it's likely to be something in one of the arch
      headers which should be easily discoverable easily on most builds of
      the specific arch.
      Signed-off-by: NTejun Heo <tj@kernel.org>
      Guess-its-ok-by: NChristoph Lameter <cl@linux-foundation.org>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
      5a0e3ad6
  8. 15 3月, 2010 4 次提交
    • A
      btrfs: use memparse · 91748467
      Akinobu Mita 提交于
      Use memparse() instead of its own private implementation.
      Signed-off-by: NAkinobu Mita <akinobu.mita@gmail.com>
      Cc: Chris Mason <chris.mason@oracle.com>
      Cc: linux-btrfs@vger.kernel.org
      Signed-off-by: NChris Mason <chris.mason@oracle.com>
      91748467
    • J
      Btrfs: make df be a little bit more understandable · bd4d1088
      Josef Bacik 提交于
      The way we report df usage is way confusing for everybody, including some other
      utilities (bacula for one).  So this patch makes df a little bit more
      understandable.  First we make used actually count the total amount of used
      space in all space info's.  This will give us a real view of how much disk space
      is in use.  Second, for blocks available, only count data space.  This makes
      things like bacula work because it says 0 when you can no longer write anymore
      data to the disk.  I think this is a nice compromise, since you will end up with
      something like the following
      
      [root@alpha ~]# df -h
      Filesystem            Size  Used Avail Use% Mounted on
      /dev/mapper/VolGroup-lv_root
                            148G   30G  111G  21% /
      /dev/sda1             194M  116M   68M  64% /boot
      tmpfs                 985M   12K  985M   1% /dev/shm
      /dev/mapper/VolGroup-LogVol02
                            145G  140G     0 100% /mnt/btrfs-test
      
      Compare this with btrfsctl -i output
      
      [root@alpha btrfs-progs-unstable]# ./btrfsctl -i /mnt/btrfs-test/
      Metadata, DUP: total=4.62GB, used=2.46GB
      System, DUP: total=8.00MB, used=24.00KB
      Data: total=134.80GB, used=134.80GB
      Metadata: total=8.00MB, used=0.00
      System: total=4.00MB, used=0.00
      operation complete
      
      This way we show that there is no more data space to be used, but we have
      another 5GB of space left for metadata.  Thanks,
      Signed-off-by: NJosef Bacik <josef@redhat.com>
      Signed-off-by: NChris Mason <chris.mason@oracle.com>
      bd4d1088
    • J
      Btrfs: make subvolid=0 mount the original default root · 4849f01d
      Josef Bacik 提交于
      Since theres not a good way to make sure the user sees the original default root
      tree id, and not to mention it's 5 so is way different than any other volume,
      just make subvol=0 mount the original default root.  This makes it a bit easier
      for users to handle in the long run.  Thanks,
      Signed-off-by: NJosef Bacik <josef@redhat.com>
      Signed-off-by: NChris Mason <chris.mason@oracle.com>
      4849f01d
    • J
      Btrfs: change how we mount subvolumes · 73f73415
      Josef Bacik 提交于
      This work is in preperation for being able to set a different root as the
      default mounting root.
      
      There is currently a problem with how we mount subvolumes.  We cannot currently
      mount a subvolume of a subvolume, you can only mount subvolumes/snapshots of the
      default subvolume.  So say you take a snapshot of the default subvolume and call
      it snap1, and then take a snapshot of snap1 and call it snap2, so now you have
      
      /
      /snap1
      /snap1/snap2
      
      as your available volumes.  Currently you can only mount / and /snap1,
      you cannot mount /snap1/snap2.  To fix this problem instead of passing
      subvolid=<name> you must pass in subvolid=<treeid>, where <treeid> is
      the tree id that gets spit out via the subvolume listing you get from
      the subvolume listing patches (btrfs filesystem list).  This allows us
      to mount /, /snap1 and /snap1/snap2 as the root volume.
      
      In addition to the above, we also now read the default dir item in the
      tree root to get the root key that it points to.  For now this just
      points at what has always been the default subvolme, but later on I plan
      to change it to point at whatever root you want to be the new default
      root, so you can just set the default mount and not have to mount with
      -o subvolid=<treeid>.  I tested this out with the above scenario and it
      worked perfectly.  Thanks,
      
      mount -o subvol operates inside the selected subvolid.  For example:
      
      mount -o subvol=snap1,subvolid=256 /dev/xxx /mnt
      
      /mnt will have the snap1 directory for the subvolume with id
      256.
      
      mount -o subvol=snap /dev/xxx /mnt
      
      /mnt will be the snap directory of whatever the default subvolume
      is.
      Signed-off-by: NJosef Bacik <josef@redhat.com>
      Signed-off-by: NChris Mason <chris.mason@oracle.com>
      73f73415
  9. 09 3月, 2010 1 次提交
  10. 29 1月, 2010 1 次提交
    • C
      Btrfs: Add mount -o compress-force · a555f810
      Chris Mason 提交于
      The default btrfs mount -o compress mode will quickly back off
      compressing a file if it notices that compression does not reduce the
      size of the data being written.  This can save considerable CPU because
      all future writes to the file go through uncompressed.
      
      But some files are both very large and have mixed data stored in
      them.  In that case, we want to add the ability to always try
      compressing data before writing it.
      
      This commit adds mount -o compress-force.  A later commit will add
      a new inode flag that does the same thing.
      Signed-off-by: NChris Mason <chris.mason@oracle.com>
      a555f810
  11. 18 12月, 2009 3 次提交
  12. 14 10月, 2009 2 次提交
  13. 30 9月, 2009 1 次提交
  14. 22 9月, 2009 2 次提交
  15. 13 7月, 2009 1 次提交
  16. 12 6月, 2009 2 次提交
  17. 11 6月, 2009 1 次提交
  18. 10 6月, 2009 4 次提交
    • C
      Btrfs: autodetect SSD devices · c289811c
      Chris Mason 提交于
      During mount, btrfs will check the queue nonrot flag
      for all the devices found in the FS.  If they are all
      non-rotating, SSD mode is enabled by default.
      
      If the FS was mounted with -o nossd, the non-rotating
      flag is ignored.
      Signed-off-by: NChris Mason <chris.mason@oracle.com>
      c289811c
    • C
      Btrfs: add mount -o ssd_spread to spread allocations out · 451d7585
      Chris Mason 提交于
      Some SSDs perform best when reusing block numbers often, while
      others perform much better when clustering strictly allocates
      big chunks of unused space.
      
      The default mount -o ssd will find rough groupings of blocks
      where there are a bunch of free blocks that might have some
      allocated blocks mixed in.
      
      mount -o ssd_spread will make sure there are no allocated blocks
      mixed in.  It should perform better on lower end SSDs.
      Signed-off-by: NChris Mason <chris.mason@oracle.com>
      451d7585
    • C
      Btrfs: Add mount -o nossd · 3b30c22f
      Chris Mason 提交于
      This allows you to turn off the ssd mode via remount.
      Signed-off-by: NChris Mason <chris.mason@oracle.com>
      3b30c22f
    • Y
      Btrfs: Mixed back reference (FORWARD ROLLING FORMAT CHANGE) · 5d4f98a2
      Yan Zheng 提交于
      This commit introduces a new kind of back reference for btrfs metadata.
      Once a filesystem has been mounted with this commit, IT WILL NO LONGER
      BE MOUNTABLE BY OLDER KERNELS.
      
      When a tree block in subvolume tree is cow'd, the reference counts of all
      extents it points to are increased by one.  At transaction commit time,
      the old root of the subvolume is recorded in a "dead root" data structure,
      and the btree it points to is later walked, dropping reference counts
      and freeing any blocks where the reference count goes to 0.
      
      The increments done during cow and decrements done after commit cancel out,
      and the walk is a very expensive way to go about freeing the blocks that
      are no longer referenced by the new btree root.  This commit reduces the
      transaction overhead by avoiding the need for dead root records.
      
      When a non-shared tree block is cow'd, we free the old block at once, and the
      new block inherits old block's references. When a tree block with reference
      count > 1 is cow'd, we increase the reference counts of all extents
      the new block points to by one, and decrease the old block's reference count by
      one.
      
      This dead tree avoidance code removes the need to modify the reference
      counts of lower level extents when a non-shared tree block is cow'd.
      But we still need to update back ref for all pointers in the block.
      This is because the location of the block is recorded in the back ref
      item.
      
      We can solve this by introducing a new type of back ref. The new
      back ref provides information about pointer's key, level and in which
      tree the pointer lives. This information allow us to find the pointer
      by searching the tree. The shortcoming of the new back ref is that it
      only works for pointers in tree blocks referenced by their owner trees.
      
      This is mostly a problem for snapshots, where resolving one of these
      fuzzy back references would be O(number_of_snapshots) and quite slow.
      The solution used here is to use the fuzzy back references in the common
      case where a given tree block is only referenced by one root,
      and use the full back references when multiple roots have a reference
      on a given block.
      
      This commit adds per subvolume red-black tree to keep trace of cached
      inodes. The red-black tree helps the balancing code to find cached
      inodes whose inode numbers within a given range.
      
      This commit improves the balancing code by introducing several data
      structures to keep the state of balancing. The most important one
      is the back ref cache. It caches how the upper level tree blocks are
      referenced. This greatly reduce the overhead of checking back ref.
      
      The improved balancing code scales significantly better with a large
      number of snapshots.
      
      This is a very large commit and was written in a number of
      pieces.  But, they depend heavily on the disk format change and were
      squashed together to make sure git bisect didn't end up in a
      bad state wrt space balancing or the format change.
      Signed-off-by: NYan Zheng <zheng.yan@oracle.com>
      Signed-off-by: NChris Mason <chris.mason@oracle.com>
      5d4f98a2
  19. 15 5月, 2009 1 次提交
  20. 09 5月, 2009 1 次提交
  21. 27 4月, 2009 1 次提交
  22. 25 4月, 2009 1 次提交
    • J
      Btrfs: try to keep a healthy ratio of metadata vs data block groups · 97e728d4
      Josef Bacik 提交于
      This patch makes the chunk allocator keep a good ratio of metadata vs data
      block groups.  By default for every 8 data block groups, we'll allocate 1
      metadata chunk, or about 12% of the disk will be allocated for metadata.  This
      can be changed by specifying the metadata_ratio mount option.
      
      This is simply the number of data block groups that have to be allocated to
      force a metadata chunk allocation.  By making sure we allocate metadata chunks
      more often, we are less likely to get into situations where the whole disk
      has been allocated as data block groups.
      Signed-off-by: NJosef Bacik <jbacik@redhat.com>
      Signed-off-by: NChris Mason <chris.mason@oracle.com>
      97e728d4
  23. 21 4月, 2009 1 次提交
  24. 03 4月, 2009 3 次提交