1. 23 Mar, 2013 1 commit
    • Kent Overstreet's avatar
      block: Add bio_end_sector() · f73a1c7d
      Kent Overstreet authored
      Just a little convenience macro - main reason to add it now is preparing
      for immutable bio vecs, it'll reduce the size of the patch that puts
      bi_sector/bi_size/bi_idx into a struct bvec_iter.
      Signed-off-by: default avatarKent Overstreet <koverstreet@google.com>
      CC: Jens Axboe <axboe@kernel.dk>
      CC: Lars Ellenberg <drbd-dev@lists.linbit.com>
      CC: Jiri Kosina <jkosina@suse.cz>
      CC: Alasdair Kergon <agk@redhat.com>
      CC: dm-devel@redhat.com
      CC: Neil Brown <neilb@suse.de>
      CC: Martin Schwidefsky <schwidefsky@de.ibm.com>
      CC: Heiko Carstens <heiko.carstens@de.ibm.com>
      CC: linux-s390@vger.kernel.org
      CC: Chris Mason <chris.mason@fusionio.com>
      CC: Steven Whitehouse <swhiteho@redhat.com>
      Acked-by: default avatarSteven Whitehouse <swhiteho@redhat.com>
      f73a1c7d
  2. 11 Oct, 2012 2 commits
  3. 01 Apr, 2012 1 commit
  4. 19 Mar, 2012 2 commits
    • NeilBrown's avatar
      md: add proper merge_bvec handling to RAID0 and Linear. · ba13da47
      NeilBrown authored
      These personalities currently set a max request size of one page
      when any member device has a merge_bvec_fn because they don't
      bother to call that function.
      
      This causes extra works in splitting and combining requests.
      
      So make the extra effort to call the merge_bvec_fn when it exists
      so that we end up with larger requests out the bottom.
      Signed-off-by: default avatarNeilBrown <neilb@suse.de>
      ba13da47
    • NeilBrown's avatar
      md: tidy up rdev_for_each usage. · dafb20fa
      NeilBrown authored
      md.h has an 'rdev_for_each()' macro for iterating the rdevs in an
      mddev.  However it uses the 'safe' version of list_for_each_entry,
      and so requires the extra variable, but doesn't include 'safe' in the
      name, which is useful documentation.
      
      Consequently some places use this safe version without needing it, and
      many use an explicity list_for_each entry.
      
      So:
       - rename rdev_for_each to rdev_for_each_safe
       - create a new rdev_for_each which uses the plain
         list_for_each_entry,
       - use the 'safe' version only where needed, and convert all other
         list_for_each_entry calls to use rdev_for_each.
      Signed-off-by: default avatarNeilBrown <neilb@suse.de>
      dafb20fa
  5. 22 Dec, 2011 1 commit
    • NeilBrown's avatar
      md/linear: fix hot-add of devices to linear arrays. · 09cd9270
      NeilBrown authored
      commit d70ed2e4
      broke hot-add to a linear array.
      After that commit, metadata if not written to devices until they
      have been fully integrated into the array as determined by
      saved_raid_disk.  That patch arranged to clear that field after
      a recovery completed.
      
      However for linear arrays, there is no recovery - the integration is
      instantaneous.  So we need to explicitly clear the saved_raid_disk
      field.
      Signed-off-by: default avatarNeilBrown <neilb@suse.de>
      09cd9270
  6. 31 Oct, 2011 1 commit
  7. 11 Oct, 2011 5 commits
  8. 12 Sep, 2011 1 commit
  9. 20 Jul, 2011 1 commit
  10. 17 Mar, 2011 1 commit
  11. 10 Mar, 2011 1 commit
  12. 21 Feb, 2011 1 commit
    • NeilBrown's avatar
      md: avoid spinlock problem in blk_throtl_exit · da9cf505
      NeilBrown authored
      blk_throtl_exit assumes that ->queue_lock still exists,
      so make sure that it does.
      To do this, we stop redirecting ->queue_lock to conf->device_lock
      and leave it pointing where it is initialised - __queue_lock.
      
      As the blk_plug functions check the ->queue_lock is held, we now
      take that spin_lock explicitly around the plug functions.  We don't
      need the locking, just the warning removal.
      
      This is needed for any kernel with the blk_throtl code, which is
      which is 2.6.37 and later.
      
      Cc: stable@kernel.org
      Signed-off-by: default avatarNeilBrown <neilb@suse.de>
      da9cf505
  13. 10 Sep, 2010 1 commit
    • Tejun Heo's avatar
      md: implment REQ_FLUSH/FUA support · e9c7469b
      Tejun Heo authored
      This patch converts md to support REQ_FLUSH/FUA instead of now
      deprecated REQ_HARDBARRIER.  In the core part (md.c), the following
      changes are notable.
      
      * Unlike REQ_HARDBARRIER, REQ_FLUSH/FUA don't interfere with
        processing of other requests and thus there is no reason to mark the
        queue congested while FLUSH/FUA is in progress.
      
      * REQ_FLUSH/FUA failures are final and its users don't need retry
        logic.  Retry logic is removed.
      
      * Preflush needs to be issued to all member devices but FUA writes can
        be handled the same way as other writes - their processing can be
        deferred to request_queue of member devices.  md_barrier_request()
        is renamed to md_flush_request() and simplified accordingly.
      
      For linear, raid0 and multipath, the core changes are enough.  raid1,
      5 and 10 need the following conversions.
      
      * raid1: Handling of FLUSH/FUA bio's can simply be deferred to
        request_queues of member devices.  Barrier related logic removed.
      
      * raid5: Queue draining logic dropped.  FUA bit is propagated through
        biodrain and stripe resconstruction such that all the updated parts
        of the stripe are written out with FUA writes if any of the dirtying
        writes was FUA.  preread_active_stripes handling in make_request()
        is updated as suggested by Neil Brown.
      
      * raid10: FUA bit needs to be propagated to write clones.
      
      linear, raid0, 1, 5 and 10 tested.
      Signed-off-by: default avatarTejun Heo <tj@kernel.org>
      Reviewed-by: default avatarNeil Brown <neilb@suse.de>
      Signed-off-by: default avatarJens Axboe <jaxboe@fusionio.com>
      e9c7469b
  14. 07 Aug, 2010 1 commit
    • Christoph Hellwig's avatar
      block: unify flags for struct bio and struct request · 7b6d91da
      Christoph Hellwig authored
      Remove the current bio flags and reuse the request flags for the bio, too.
      This allows to more easily trace the type of I/O from the filesystem
      down to the block driver.  There were two flags in the bio that were
      missing in the requests:  BIO_RW_UNPLUG and BIO_RW_AHEAD.  Also I've
      renamed two request flags that had a superflous RW in them.
      
      Note that the flags are in bio.h despite having the REQ_ name - as
      blkdev.h includes bio.h that is the only way to go for now.
      Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
      Signed-off-by: default avatarJens Axboe <jaxboe@fusionio.com>
      7b6d91da
  15. 18 May, 2010 3 commits
  16. 17 May, 2010 1 commit
    • NeilBrown's avatar
      md/linear: avoid possible oops and array stop · ef2f80ff
      NeilBrown authored
      Since commit ef286f6f
      it has been important that each personality clears
      ->private in the ->stop() function, or sets it to a
      attribute group to be removed.
      linear.c doesn't.  This can sometimes lead to an oops,
      though it doesn't always.
      
      Suitable for 2.6.33-stable and 2.6.34.
      Signed-off-by: default avatarNeilBrown <neilb@suse.de>
      Cc: stable@kernel.org
      ef2f80ff
  17. 30 Mar, 2010 1 commit
    • Tejun Heo's avatar
      include cleanup: Update gfp.h and slab.h includes to prepare for breaking... · 5a0e3ad6
      Tejun Heo authored
      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: default avatarTejun Heo <tj@kernel.org>
      Guess-its-ok-by: default avatarChristoph Lameter <cl@linux-foundation.org>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
      5a0e3ad6
  18. 16 Mar, 2010 1 commit
    • NeilBrown's avatar
      md: deal with merge_bvec_fn in component devices better. · 627a2d3c
      NeilBrown authored
      If a component device has a merge_bvec_fn then as we never call it
      we must ensure we never need to.  Currently this is done by setting
      max_sector to 1 PAGE, however this does not stop a bio being created
      with several sub-page iovecs that would violate the merge_bvec_fn.
      
      So instead set max_segments to 1 and set the segment boundary to the
      same as a page boundary to ensure there is only ever one single-page
      segment of IO requested at a time.
      
      This can particularly be an issue when 'xen' is used as it is
      known to submit multiple small buffers in a single bio.
      Signed-off-by: default avatarNeilBrown <neilb@suse.de>
      Cc: stable@kernel.org
      627a2d3c
  19. 26 Feb, 2010 1 commit
  20. 14 Dec, 2009 2 commits
    • NeilBrown's avatar
      md: add MODULE_DESCRIPTION for all md related modules. · 0efb9e61
      NeilBrown authored
      Suggested by  Oren Held <orenhe@il.ibm.com>
      Signed-off-by: default avatarNeilBrown <neilb@suse.de>
      0efb9e61
    • NeilBrown's avatar
      md: support barrier requests on all personalities. · a2826aa9
      NeilBrown authored
      Previously barriers were only supported on RAID1.  This is because
      other levels requires synchronisation across all devices and so needed
      a different approach.
      Here is that approach.
      
      When a barrier arrives, we send a zero-length barrier to every active
      device.  When that completes - and if the original request was not
      empty -  we submit the barrier request itself (with the barrier flag
      cleared) and then submit a fresh load of zero length barriers.
      
      The barrier request itself is asynchronous, but any subsequent
      request will block until the barrier completes.
      
      The reason for clearing the barrier flag is that a barrier request is
      allowed to fail.  If we pass a non-empty barrier through a striping
      raid level it is conceivable that part of it could succeed and part
      could fail.  That would be way too hard to deal with.
      So if the first run of zero length barriers succeed, we assume all is
      sufficiently well that we send the request and ignore errors in the
      second run of barriers.
      
      RAID5 needs extra care as write requests may not have been submitted
      to the underlying devices yet.  So we flush the stripe cache before
      proceeding with the barrier.
      
      Note that the second set of zero-length barriers are submitted
      immediately after the original request is submitted.  Thus when
      a personality finds mddev->barrier to be set during make_request,
      it should not return from make_request until the corresponding
      per-device request(s) have been queued.
      
      That will be done in later patches.
      Signed-off-by: default avatarNeilBrown <neilb@suse.de>
      Reviewed-by: default avatarAndre Noll <maan@systemlinux.org>
      a2826aa9
  21. 23 Sep, 2009 1 commit
  22. 11 Sep, 2009 1 commit
  23. 03 Aug, 2009 2 commits
    • NeilBrown's avatar
      md: Use revalidate_disk to effect changes in size of device. · 449aad3e
      NeilBrown authored
      As revalidate_disk calls check_disk_size_change, it will cause
      any capacity change of a gendisk to be propagated to the blockdev
      inode.  So use that instead of mucking about with locks and
      i_size_write.
      
      Also add a call to revalidate_disk in do_md_run and a few other places
      where the gendisk capacity is changed.
      Signed-off-by: default avatarNeilBrown <neilb@suse.de>
      449aad3e
    • Andre Noll's avatar
      md: Push down data integrity code to personalities. · ac5e7113
      Andre Noll authored
      This patch replaces md_integrity_check() by two new public functions:
      md_integrity_register() and md_integrity_add_rdev() which are both
      personality-independent.
      
      md_integrity_register() is called from the ->run and ->hot_remove
      methods of all personalities that support data integrity.  The
      function iterates over the component devices of the array and
      determines if all active devices are integrity capable and if their
      profiles match. If this is the case, the common profile is registered
      for the mddev via blk_integrity_register().
      
      The second new function, md_integrity_add_rdev() is called from the
      ->hot_add_disk methods, i.e. whenever a new device is being added
      to a raid array. If the new device does not support data integrity,
      or has a profile different from the one already registered, data
      integrity for the mddev is disabled.
      
      For raid0 and linear, only the call to md_integrity_register() from
      the ->run method is necessary.
      Signed-off-by: default avatarAndre Noll <maan@systemlinux.org>
      Signed-off-by: default avatarNeilBrown <neilb@suse.de>
      ac5e7113
  24. 01 Jul, 2009 1 commit
  25. 17 Jun, 2009 5 commits
    • NeilBrown's avatar
      md/linear: use call_rcu to free obsolete 'conf' structures. · 495d3573
      NeilBrown authored
      Current, when we update the 'conf' structure, when adding a
      drive to a linear array, we keep the old version around until
      the array is finally stopped, as it is not safe to free it
      immediately.
      
      Now that we have rcu protection on all accesses to 'conf',
      we can use call_rcu to free it more promptly.
      Signed-off-by: default avatarNeilBrown <neilb@suse.de>
      495d3573
    • SandeepKsinha's avatar
      md linear: Protecting mddev with rcu locks to avoid races · af11c397
      SandeepKsinha authored
      
      Due to the lack of memory ordering guarantees, we may have races around
      mddev->conf.
      
      In particular, the correct contents of the structure we get from
      dereferencing ->private might not be visible to this CPU yet, and
      they might not be correct w.r.t mddev->raid_disks.
      
      This patch addresses the problem using rcu protection to avoid
      such race conditions.
      Signed-off-by: default avatarSandeepKsinha <sandeepksinha@gmail.com>
      Signed-off-by: default avatarNeilBrown <neilb@suse.de>
      af11c397
    • Andre Noll's avatar
      md: Move check for bitmap presence to personality code. · 0894cc30
      Andre Noll authored
      If the superblock of a component device indicates the presence of a
      bitmap but the corresponding raid personality does not support bitmaps
      (raid0, linear, multipath, faulty), then something is seriously wrong
      and we'd better refuse to run such an array.
      
      Currently, this check is performed while the superblocks are examined,
      i.e. before entering personality code. Therefore the generic md layer
      must know which raid levels support bitmaps and which do not.
      
      This patch avoids this layer violation without adding identical code
      to various personalities. This is accomplished by introducing a new
      public function to md.c, md_check_no_bitmap(), which replaces the
      hard-coded checks in the superblock loading functions.
      
      A call to md_check_no_bitmap() is added to the ->run method of each
      personality which does not support bitmaps and assembly is aborted
      if at least one component device contains a bitmap.
      Signed-off-by: default avatarAndre Noll <maan@systemlinux.org>
      Signed-off-by: default avatarNeilBrown <neilb@suse.de>
      0894cc30
    • NeilBrown's avatar
      md: raid0/linear: ensure device sizes are rounded to chunk size. · 13f2682b
      NeilBrown authored
      This is currently ensured by common code, but it is more reliable to
      ensure it where it is needed in personality code.
      All the other personalities that care already round the size to
      the chunk_size.  raid0 and linear are the only hold-outs.
      Signed-off-by: default avatarNeilBrown <neilb@suse.de>
      13f2682b
    • Andre Noll's avatar
      md: Make mddev->chunk_size sector-based. · 9d8f0363
      Andre Noll authored
      This patch renames the chunk_size field to chunk_sectors with the
      implied change of semantics.  Since
      
      	is_power_of_2(chunk_size) = is_power_of_2(chunk_sectors << 9)
      				  = is_power_of_2(chunk_sectors)
      
      these bits don't need an adjustment for the shift.
      Signed-off-by: default avatarAndre Noll <maan@systemlinux.org>
      Signed-off-by: default avatarNeilBrown <neilb@suse.de>
      9d8f0363
  26. 16 Jun, 2009 1 commit