1. 09 4月, 2009 6 次提交
  2. 03 4月, 2009 10 次提交
  3. 17 3月, 2009 1 次提交
    • M
      dm crypt: wait for endio to complete before destruction · b35f8caa
      Milan Broz 提交于
      The following oops has been reported when dm-crypt runs over a loop device.
      
      ...
      [   70.381058] Process loop0 (pid: 4268, ti=cf3b2000 task=cf1cc1f0 task.ti=cf3b2000)
      ...
      [   70.381058] Call Trace:
      [   70.381058]  [<d0d76601>] ? crypt_dec_pending+0x5e/0x62 [dm_crypt]
      [   70.381058]  [<d0d767b8>] ? crypt_endio+0xa2/0xaa [dm_crypt]
      [   70.381058]  [<d0d76716>] ? crypt_endio+0x0/0xaa [dm_crypt]
      [   70.381058]  [<c01a2f24>] ? bio_endio+0x2b/0x2e
      [   70.381058]  [<d0806530>] ? dec_pending+0x224/0x23b [dm_mod]
      [   70.381058]  [<d08066e4>] ? clone_endio+0x79/0xa4 [dm_mod]
      [   70.381058]  [<d080666b>] ? clone_endio+0x0/0xa4 [dm_mod]
      [   70.381058]  [<c01a2f24>] ? bio_endio+0x2b/0x2e
      [   70.381058]  [<c02bad86>] ? loop_thread+0x380/0x3b7
      [   70.381058]  [<c02ba8a1>] ? do_lo_send_aops+0x0/0x165
      [   70.381058]  [<c013754f>] ? autoremove_wake_function+0x0/0x33
      [   70.381058]  [<c02baa06>] ? loop_thread+0x0/0x3b7
      
      When a table is being replaced, it waits for I/O to complete
      before destroying the mempool, but the endio function doesn't
      call mempool_free() until after completing the bio.
      
      Fix it by swapping the order of those two operations.
      
      The same problem occurs in dm.c with md referenced after dec_pending.
      Again, we swap the order.
      
      Cc: stable@kernel.org
      Signed-off-by: NMilan Broz <mbroz@redhat.com>
      Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
      b35f8caa
  4. 06 1月, 2009 5 次提交
    • M
      dm: add name and uuid to sysfs · 784aae73
      Milan Broz 提交于
      Implement simple read-only sysfs entry for device-mapper block device.
      
      This patch adds a simple sysfs directory named "dm" under block device
      properties and implements
      	- name attribute (string containing mapped device name)
      	- uuid attribute (string containing UUID, or empty string if not set)
      
      The kobject is embedded in mapped_device struct, so no additional
      memory allocation is needed for initializing sysfs entry.
      
      During the processing of sysfs attribute we need to lock mapped device
      which is done by a new function dm_get_from_kobj, which returns the md
      associated with kobject and increases the usage count.
      
      Each 'show attribute' function is responsible for its own locking.
      Signed-off-by: NMilan Broz <mbroz@redhat.com>
      Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
      784aae73
    • M
      dm table: rework reference counting · d5816876
      Mikulas Patocka 提交于
      Rework table reference counting.
      
      The existing code uses a reference counter. When the last reference is
      dropped and the counter reaches zero, the table destructor is called.
      Table reference counters are acquired/released from upcalls from other
      kernel code (dm_any_congested, dm_merge_bvec, dm_unplug_all).
      If the reference counter reaches zero in one of the upcalls, the table
      destructor is called from almost random kernel code.
      
      This leads to various problems:
      * dm_any_congested being called under a spinlock, which calls the
        destructor, which calls some sleeping function.
      * the destructor attempting to take a lock that is already taken by the
        same process.
      * stale reference from some other kernel code keeps the table
        constructed, which keeps some devices open, even after successful
        return from "dmsetup remove". This can confuse lvm and prevent closing
        of underlying devices or reusing device minor numbers.
      
      The patch changes reference counting so that the table destructor can be
      called only at predetermined places.
      
      The table has always exactly one reference from either mapped_device->map
      or hash_cell->new_map. After this patch, this reference is not counted
      in table->holders.  A pair of dm_create_table/dm_destroy_table functions
      is used for table creation/destruction.
      
      Temporary references from the other code increase table->holders. A pair
      of dm_table_get/dm_table_put functions is used to manipulate it.
      
      When the table is about to be destroyed, we wait for table->holders to
      reach 0. Then, we call the table destructor.  We use active waiting with
      msleep(1), because the situation happens rarely (to one user in 5 years)
      and removing the device isn't performance-critical task: the user doesn't
      care if it takes one tick more or not.
      
      This way, the destructor is called only at specific points
      (dm_table_destroy function) and the above problems associated with lazy
      destruction can't happen.
      
      Finally remove the temporary protection added to dm_any_congested().
      Signed-off-by: NMikulas Patocka <mpatocka@redhat.com>
      Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
      d5816876
    • A
      dm: support barriers on simple devices · ab4c1424
      Andi Kleen 提交于
      Implement barrier support for single device DM devices
      
      This patch implements barrier support in DM for the common case of dm linear
      just remapping a single underlying device. In this case we can safely
      pass the barrier through because there can be no reordering between
      devices.
      
       NB. Any DM device might cease to support barriers if it gets
           reconfigured so code must continue to allow for a possible
           -EOPNOTSUPP on every barrier bio submitted.  - agk
      Signed-off-by: NAndi Kleen <ak@suse.de>
      Signed-off-by: NMikulas Patocka <mpatocka@redhat.com>
      Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
      ab4c1424
    • K
      dm request: add caches · 8fbf26ad
      Kiyoshi Ueda 提交于
      This patch prepares some kmem_caches for request-based dm.
      Signed-off-by: NKiyoshi Ueda <k-ueda@ct.jp.nec.com>
      Signed-off-by: NJun'ichi Nomura <j-nomura@ce.jp.nec.com>
      Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
      8fbf26ad
    • M
      dm table: drop reference at unbind · a1b51e98
      Mikulas Patocka 提交于
      Move one dm_table_put() so that the last reference in the thread
      gets dropped in __unbind().
      
      This is required for a following patch,
      dm-table-rework-reference-counting.patch, which will change the logic in
      such a way that table destructor is called only at specific points in
      the code.
      Signed-off-by: NMikulas Patocka <mpatocka@redhat.com>
      Signed-off-by: NAlasdair G Kergon <agk@redhat.com>
      a1b51e98
  5. 29 12月, 2008 1 次提交
    • J
      bio: allow individual slabs in the bio_set · bb799ca0
      Jens Axboe 提交于
      Instead of having a global bio slab cache, add a reference to one
      in each bio_set that is created. This allows for personalized slabs
      in each bio_set, so that they can have bios of different sizes.
      
      This means we can personalize the bios we return. File systems may
      want to embed the bio inside another structure, to avoid allocation
      more items (and stuffing them in ->bi_private) after the get a bio.
      Or we may want to embed a number of bio_vecs directly at the end
      of a bio, to avoid doing two allocations to return a bio. This is now
      possible.
      Signed-off-by: NJens Axboe <jens.axboe@oracle.com>
      bb799ca0
  6. 26 11月, 2008 2 次提交
  7. 14 11月, 2008 2 次提交
  8. 22 10月, 2008 3 次提交
  9. 21 10月, 2008 3 次提交
    • A
      [PATCH] switch dm · fe5f9f2c
      Al Viro 提交于
      ioctl() doesn't need BKL here
      Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
      fe5f9f2c
    • A
      [PATCH] beginning of methods conversion · d4430d62
      Al Viro 提交于
      To keep the size of changesets sane we split the switch by drivers;
      to keep the damn thing bisectable we do the following:
      	1) rename the affected methods, add ones with correct
      prototypes, make (few) callers handle both.  That's this changeset.
      	2) for each driver convert to new methods.  *ALL* drivers
      are converted in this series.
      	3) kill the old (renamed) methods.
      
      Note that it _is_ a flagday; all in-tree drivers are converted and by the
      end of this series no trace of old methods remain.  The only reason why
      we do that this way is to keep the damn thing bisectable and allow per-driver
      debugging if anything goes wrong.
      
      New methods:
      	open(bdev, mode)
      	release(disk, mode)
      	ioctl(bdev, mode, cmd, arg)		/* Called without BKL */
      	compat_ioctl(bdev, mode, cmd, arg)
      	locked_ioctl(bdev, mode, cmd, arg)	/* Called with BKL, legacy */
      Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
      d4430d62
    • A
      [PATCH] lose unused arguments in dm ioctl callbacks · 647b3d00
      Al Viro 提交于
      Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
      647b3d00
  10. 09 10月, 2008 4 次提交
    • T
      block: move stats from disk to part0 · 074a7aca
      Tejun Heo 提交于
      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: NTejun Heo <tj@kernel.org>
      Signed-off-by: NJens Axboe <jens.axboe@oracle.com>
      074a7aca
    • T
      block: implement and use {disk|part}_to_dev() · ed9e1982
      Tejun Heo 提交于
      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: NTejun Heo <tj@kernel.org>
      Signed-off-by: NJens Axboe <jens.axboe@oracle.com>
      ed9e1982
    • T
      block: fix diskstats access · c9959059
      Tejun Heo 提交于
      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: NTejun Heo <tj@kernel.org>
      Cc: Peter Zijlstra <peterz@infradead.org>
      Signed-off-by: NJens Axboe <jens.axboe@oracle.com>
      c9959059
    • T
      block: don't depend on consecutive minor space · f331c029
      Tejun Heo 提交于
      * 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: NTejun Heo <tj@kernel.org>
      Signed-off-by: NJens Axboe <jens.axboe@oracle.com>
      f331c029
  11. 01 10月, 2008 2 次提交
  12. 21 7月, 2008 1 次提交