1. 09 Oct, 2008 19 commits
    • Tejun Heo's avatar
      block: move stats from disk to part0 · 074a7aca
      Tejun Heo authored
      Move stats related fields - stamp, in_flight, dkstats - from disk to
      part0 and unify stat handling such that...
      
      * part_stat_*() now updates part0 together if the specified partition
        is not part0.  ie. part_stat_*() are now essentially all_stat_*().
      
      * {disk|all}_stat_*() are gone.
      
      * part_round_stats() is updated similary.  It handles part0 stats
        automatically and disk_round_stats() is killed.
      
      * part_{inc|dec}_in_fligh() is implemented which automatically updates
        part0 stats for parts other than part0.
      
      * disk_map_sector_rcu() is updated to return part0 if no part matches.
        Combined with the above changes, this makes NULL special case
        handling in callers unnecessary.
      
      * Separate stats show code paths for disk are collapsed into part
        stats show code paths.
      
      * Rename disk_stat_lock/unlock() to part_stat_lock/unlock()
      
      While at it, reposition stat handling macros a bit and add missing
      parentheses around macro parameters.
      Signed-off-by: default avatarTejun Heo <tj@kernel.org>
      Signed-off-by: default avatarJens Axboe <jens.axboe@oracle.com>
      074a7aca
    • Tejun Heo's avatar
      block: always set bdev->bd_part · 0762b8bd
      Tejun Heo authored
      Till now, bdev->bd_part is set only if the bdev was for parts other
      than part0.  This patch makes bdev->bd_part always set so that code
      paths don't have to differenciate common handling.
      Signed-off-by: default avatarTejun Heo <tj@kernel.org>
      Signed-off-by: default avatarJens Axboe <jens.axboe@oracle.com>
      0762b8bd
    • Tejun Heo's avatar
      block: move policy from disk to part0 · b7db9956
      Tejun Heo authored
      Move disk->policy to part0->policy.  Implement and use get_disk_ro().
      Signed-off-by: default avatarTejun Heo <tj@kernel.org>
      Signed-off-by: default avatarJens Axboe <jens.axboe@oracle.com>
      b7db9956
    • Tejun Heo's avatar
      block: move capacity from disk to part0 · 80795aef
      Tejun Heo authored
      Move disk->capacity to part0->nr_sects and convert all users who
      directly accessed the field to use {get|set}_capacity().  This is done
      early to allow the __dev field to be moved.
      Signed-off-by: default avatarTejun Heo <tj@kernel.org>
      Signed-off-by: default avatarJens Axboe <jens.axboe@oracle.com>
      80795aef
    • Tejun Heo's avatar
      block: implement and use {disk|part}_to_dev() · ed9e1982
      Tejun Heo authored
      Implement {disk|part}_to_dev() and use them to access generic device
      instead of directly dereferencing {disk|part}->dev.  To make sure no
      user is left behind, rename generic devices fields to __dev.
      
      This is in preparation of unifying partition 0 handling with other
      partitions.
      Signed-off-by: default avatarTejun Heo <tj@kernel.org>
      Signed-off-by: default avatarJens Axboe <jens.axboe@oracle.com>
      ed9e1982
    • Tejun Heo's avatar
      block: implement CONFIG_DEBUG_BLOCK_EXT_DEVT · 870d6656
      Tejun Heo authored
      Extended devt introduces non-contiguos device numbers.  This patch
      implements a debug option which forces most devt allocations to be
      from the extended area and spreads them out.  This is enabled by
      default if DEBUG_KERNEL is set and achieves...
      
      1. Detects code paths in kernel or userland which expect predetermined
         consecutive device numbers.
      
      2. When something goes wrong, avoid corruption as adding to the minor
         of earlier partition won't lead to the wrong but valid device.
      Signed-off-by: default avatarTejun Heo <tj@kernel.org>
      Signed-off-by: default avatarJens Axboe <jens.axboe@oracle.com>
      870d6656
    • Tejun Heo's avatar
      sd/ide-disk: apply extended minors to sd and ide · f615b48c
      Tejun Heo authored
      Update sd and ide-disk such that they can take advantage of extended
      minors.
      
      ide-disk already has 64 minors per device and currently doesn't use
      extended minors although after this patch it can be turned on by
      simply tweaking constants.
      
      sd only had 16 minors per device causing problems on certain peculiar
      configurations.  This patch lifts the restriction and enables it to
      use upto 64 minors.
      Signed-off-by: default avatarTejun Heo <tj@kernel.org>
      Signed-off-by: default avatarJens Axboe <jens.axboe@oracle.com>
      f615b48c
    • Tejun Heo's avatar
      block: fix diskstats access · c9959059
      Tejun Heo authored
      There are two variants of stat functions - ones prefixed with double
      underbars which don't care about preemption and ones without which
      disable preemption before manipulating per-cpu counters.  It's unclear
      whether the underbarred ones assume that preemtion is disabled on
      entry as some callers don't do that.
      
      This patch unifies diskstats access by implementing disk_stat_lock()
      and disk_stat_unlock() which take care of both RCU (for partition
      access) and preemption (for per-cpu counter access).  diskstats access
      should always be enclosed between the two functions.  As such, there's
      no need for the versions which disables preemption.  They're removed
      and double underbars ones are renamed to drop the underbars.  As an
      extra argument is added, there's no danger of using the old version
      unconverted.
      
      disk_stat_lock() uses get_cpu() and returns the cpu index and all
      diskstat functions which access per-cpu counters now has @cpu
      argument to help RT.
      
      This change adds RCU or preemption operations at some places but also
      collapses several preemption ops into one at others.  Overall, the
      performance difference should be negligible as all involved ops are
      very lightweight per-cpu ones.
      Signed-off-by: default avatarTejun Heo <tj@kernel.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Signed-off-by: default avatarJens Axboe <jens.axboe@oracle.com>
      c9959059
    • Tejun Heo's avatar
      block: fix disk->part[] dereferencing race · e71bf0d0
      Tejun Heo authored
      disk->part[] is protected by its matching bdev's lock.  However,
      non-critical accesses like collecting stats and printing out sysfs and
      proc information used to be performed without any locking.  As
      partitions can come and go dynamically, partitions can go away
      underneath those non-critical accesses.  As some of those accesses are
      writes, this theoretically can lead to silent corruption.
      
      This patch fixes the race by using RCU for the partition array and dev
      reference counter to hold partitions.
      
      * Rename disk->part[] to disk->__part[] to make sure no one outside
        genhd layer proper accesses it directly.
      
      * Use RCU for disk->__part[] dereferencing.
      
      * Implement disk_{get|put}_part() which can be used to get and put
        partitions from gendisk respectively.
      
      * Iterators are implemented to help iterate through all partitions
        safely.
      
      * Functions which require RCU readlock are marked with _rcu suffix.
      
      * Use disk_put_part() in __blkdev_put() instead of directly putting
        the contained kobject.
      Signed-off-by: default avatarTejun Heo <tj@kernel.org>
      Signed-off-by: default avatarJens Axboe <jens.axboe@oracle.com>
      e71bf0d0
    • Tejun Heo's avatar
      block: don't depend on consecutive minor space · f331c029
      Tejun Heo authored
      * Implement disk_devt() and part_devt() and use them to directly
        access devt instead of computing it from ->major and ->first_minor.
      
        Note that all references to ->major and ->first_minor outside of
        block layer is used to determine devt of the disk (the part0) and as
        ->major and ->first_minor will continue to represent devt for the
        disk, converting these users aren't strictly necessary.  However,
        convert them for consistency.
      
      * Implement disk_max_parts() to avoid directly deferencing
        genhd->minors.
      
      * Update bdget_disk() such that it doesn't assume consecutive minor
        space.
      
      * Move devt computation from register_disk() to add_disk() and make it
        the only one (all other usages use the initially determined value).
      
      These changes clean up the code and will help disk->part dereference
      fix and extended block device numbers.
      Signed-off-by: default avatarTejun Heo <tj@kernel.org>
      Signed-off-by: default avatarJens Axboe <jens.axboe@oracle.com>
      f331c029
    • Tejun Heo's avatar
      block: misc updates · 310a2c10
      Tejun Heo authored
      This patch makes the following misc updates in preparation for
      disk->part dereference fix and extended block devt support.
      
      * implment part_to_disk()
      
      * fix comment about gendisk->part indexing
      
      * rename get_part() to disk_map_sector()
      
      * don't use n which is always zero while printing disk information in
        diskstats_show()
      Signed-off-by: default avatarTejun Heo <tj@kernel.org>
      Signed-off-by: default avatarJens Axboe <jens.axboe@oracle.com>
      310a2c10
    • Tejun Heo's avatar
      driver-core: use klist for class device list and implement iterator · 5a3ceb86
      Tejun Heo authored
      Iterating over entries using callback usually isn't too fun especially
      when the entry being iterated over can't be manipulated freely.  This
      patch converts class->p->class_devices to klist and implements class
      device iterator so that the users can freely build their own control
      structure.  The users are also free to call back into class code
      without worrying about locking.
      
      class_for_each_device() and class_find_device() are converted to use
      the new iterators, so their users don't have to worry about locking
      anymore either.
      
      Note: This depends on klist-dont-iterate-over-deleted-entries patch
      because class_intf->add/remove_dev() depends on proper synchronization
      with device removal.
      Signed-off-by: default avatarTejun Heo <tj@kernel.org>
      Cc: Greg Kroah-Hartman <gregkh@suse.de>
      Cc: Jens Axboe <jens.axboe@oracle.com>
      Signed-off-by: default avatarJens Axboe <jens.axboe@oracle.com>
      5a3ceb86
    • Jens Axboe's avatar
      block: make bi_phys_segments an unsigned int instead of short · 5b99c2ff
      Jens Axboe authored
      raid5 can overflow with more than 255 stripes, and we can increase it
      to an int for free on both 32 and 64-bit archs due to the padding.
      Signed-off-by: default avatarJens Axboe <jens.axboe@oracle.com>
      5b99c2ff
    • Jens Axboe's avatar
      960e739d
    • Mikulas Patocka's avatar
      drop vmerge accounting · 5df97b91
      Mikulas Patocka authored
      Remove hw_segments field from struct bio and struct request. Without virtual
      merge accounting they have no purpose.
      Signed-off-by: default avatarMikulas Patocka <mpatocka@redhat.com>
      Signed-off-by: default avatarJens Axboe <jens.axboe@oracle.com>
      5df97b91
    • Fernando Luis Vázquez Cao's avatar
      virtio_blk: use a wrapper function to access io context information of IO requests · 766ca442
      Fernando Luis Vázquez Cao authored
      struct request has an ioprio member but it is never updated because
      currently bios do not hold io context information. The implication of
      this is that virtio_blk ends up passing useless information to the
      backend driver.
      
      That said, some IO schedulers such as CFQ do store io context
      information in struct request, but use private members for that, which
      means that that information cannot be directly accessed in a IO
      scheduler-independent way.
      
      This patch adds a function to obtain the ioprio of a request. We should
      avoid accessing ioprio directly and use this function instead, so that
      its users do not have to care about future changes in block layer
      structures or what the currently active IO controller is.
      
      This patch does not introduce any functional changes but paves the way
      for future clean-ups and enhancements.
      Signed-off-by: default avatarFernando Luis Vazquez Cao <fernando@oss.ntt.co.jp>
      Acked-by: default avatarRusty Russell <rusty@rustcorp.com.au>
      Signed-off-by: default avatarJens Axboe <jens.axboe@oracle.com>
      766ca442
    • David Woodhouse's avatar
      Kill REQ_TYPE_FLUSH · 1a8e2bdd
      David Woodhouse authored
      It was only used by ps3disk, and it should probably have been
      REQ_TYPE_LINUX_BLOCK + REQ_LB_OP_FLUSH.
      Signed-off-by: default avatarDavid Woodhouse <David.Woodhouse@intel.com>
      Signed-off-by: default avatarJens Axboe <jens.axboe@oracle.com>
      1a8e2bdd
    • David Woodhouse's avatar
      Support 'discard sectors' operation. · fdc53971
      David Woodhouse authored
      We can benefit from knowing that the file system no longer cares about
      the contents of certain sectors, by throwing them away immediately and
      then never having to garbage collect them, and using the extra free
      space to make our operations more efficient. Do so.
      Signed-off-by: default avatarDavid Woodhouse <David.Woodhouse@intel.com>
      Signed-off-by: default avatarJens Axboe <jens.axboe@oracle.com>
      fdc53971
    • David Woodhouse's avatar
  2. 07 Oct, 2008 1 commit
  3. 06 Oct, 2008 4 commits
  4. 05 Oct, 2008 16 commits