1. 17 9月, 2010 2 次提交
    • N
      md: fix v1.x metadata update when a disk is missing. · ddcf3522
      NeilBrown 提交于
      If an array with 1.x metadata is assembled with the last disk missing,
      md doesn't properly record the fact that the disk was missing.
      
      This is unlikely to cause a real problem as the event count will be
      different to the count on the missing disk so it won't be included in
      the array.  However it could still cause confusion.
      
      So make sure we clear all the relevant slots, not just the early ones.
      Signed-off-by: NNeilBrown <neilb@suse.de>
      ddcf3522
    • N
      md: call md_update_sb even for 'external' metadata arrays. · 126925c0
      NeilBrown 提交于
      Now that we depend on md_update_sb to clear variable bits in
      mddev->flags (rather than trying not to set them) it is important to
      always call md_update_sb when appropriate.
      
      md_check_recovery has this job but explicitly avoids it for ->external
      metadata arrays.  This is not longer appropraite, or needed.
      
      However we do want to avoid taking the mddev lock if only
      MD_CHANGE_PENDING is set as that is not cleared by md_update_sb for
      external-metadata arrays.
      Reported-by: N"Kwolek, Adam" <adam.kwolek@intel.com>
      Signed-off-by: NNeilBrown <neilb@suse.de>
      126925c0
  2. 30 8月, 2010 2 次提交
    • N
      md: resolve confusion of MD_CHANGE_CLEAN · 070dc6dd
      NeilBrown 提交于
      MD_CHANGE_CLEAN is used for two different purposes and this leads to
      confusion.
      One of the purposes is largely mirrored by MD_CHANGE_PENDING which is
      not used for anything else, so have MD_CHANGE_PENDING take over that
      purpose fully.
      
      The two purposes are:
       1/ tell md_update_sb that an update is needed and that it is just a
         clean/dirty transition.
       2/ tell user-space that an transition from clean to dirty is pending
          (something wants to write), and tell te kernel (by clearin the
          flag) that the transition is OK.
      
      The first purpose remains wit MD_CHANGE_CLEAN, the second is moved
      fully to MD_CHANGE_PENDING.
      
      This means that various places which conditionally set or cleared
      MD_CHANGE_CLEAN no longer need to be conditional.
      Signed-off-by: NNeilBrown <neilb@suse.de>
      070dc6dd
    • D
      md: don't clear MD_CHANGE_CLEAN in md_update_sb() for external arrays · bd52b746
      Dan Williams 提交于
      If this bit is cleared in md_update_sb() the kernel will allow writes to the
      array if userspace triggers md_allow_write(), e.g. through stripe_cache_size,
      when mdmon is not active.  When mdmon is active the array transitions to
      active-idle bypassing write-pending, setting up a race for mdmon to set the
      array clean before a write arrives.
      Signed-off-by: NDan Williams <dan.j.williams@intel.com>
      Signed-off-by: NNeilBrown <neilb@suse.de>
      bd52b746
  3. 18 8月, 2010 1 次提交
    • N
      Update recovery_offset even when external metadata is used. · 3a3a5ddb
      NeilBrown 提交于
      The update of ->recovery_offset in sync_sbs is appropriate even then external
      metadata is in use.  However sync_sbs is only called when native
      metadata is used.
      
      So move that update in to the top of md_update_sb (which is the only
      caller of sync_sbs) before the test on ->external.
      
      This moves the update out of ->write_lock protection, but those fields
      only need ->reconfig_mutex protection which they still have.
      
      Also move the test on ->persistent up to where ->external is set as
      for metadata update purposes they are the same.
      
      Clear MD_CHANGE_DEVS and MD_CHANGE_CLEAN as they can only be confusing
      if ->external is set or ->persistent isn't.
      
      Finally move the update of ->utime down as it is only relevent (like
      the ->events update) for native metadata.
      Signed-off-by: NNeilBrown <neilb@suse.de>
      Reported-by: N"Kwolek, Adam" <adam.kwolek@intel.com>
      3a3a5ddb
  4. 08 8月, 2010 5 次提交
    • N
      md: clean up do_md_stop · 6e17b027
      NeilBrown 提交于
      There is only one error exit from do_md_stop, so make that more
      explicit and discard the 'err' variable.
      Also drop the 'revalidate' variable by moving the unlock calls around.
      Signed-off-by: NNeilBrown <neilb@suse.de>
      6e17b027
    • N
      md: fix another deadlock with removing sysfs attributes. · bb4f1e9d
      NeilBrown 提交于
      Move the deletion of sysfs attributes from reconfig_mutex to
      open_mutex didn't really help as a process can try to take
      open_mutex while holding reconfig_mutex, so the same deadlock can
      happen, just requiring one more process to be involved in the chain.
      
      I looks like I cannot easily use locking to wait for the sysfs
      deletion to complete, so don't.
      
      The only things that we cannot do while the deletions are still
      pending is other things which can change the sysfs namespace: run,
      takeover, stop.  Each of these can fail with -EBUSY.
      So set a flag while doing a sysfs deletion, and fail run, takeover,
      stop if that flag is set.
      
      This is suitable for 2.6.35.x
      
      Cc: stable@kernel.org
      Signed-off-by: NNeilBrown <neilb@suse.de>
      bb4f1e9d
    • D
      md: move revalidate_disk() back outside open_mutex · 147e0b6a
      Dan Williams 提交于
      Commit b821eaa5 "md: remove ->changed and related code" moved
      revalidate_disk() under open_mutex, and lockdep noticed.
      
      [ INFO: possible circular locking dependency detected ]
      2.6.32-mdadm-locking #1
      -------------------------------------------------------
      mdadm/3640 is trying to acquire lock:
       (&bdev->bd_mutex){+.+.+.}, at: [<ffffffff811acecb>] revalidate_disk+0x5b/0x90
      
      but task is already holding lock:
       (&mddev->open_mutex){+.+...}, at: [<ffffffffa055e07a>] do_md_stop+0x4a/0x4d0 [md_mod]
      
      which lock already depends on the new lock.
      
      It is suitable for 2.6.35.x
      
      Cc: <stable@kernel.org>
      Reported-by: NPrzemyslaw Czarnowski <przemyslaw.hawrylewicz.czarnowski@intel.com>
      Signed-off-by: NDan Williams <dan.j.williams@intel.com>
      Signed-off-by: NNeilBrown <neilb@suse.de>
      147e0b6a
    • A
      block: push down BKL into .open and .release · 6e9624b8
      Arnd Bergmann 提交于
      The open and release block_device_operations are currently
      called with the BKL held. In order to change that, we must
      first make sure that all drivers that currently rely
      on this have no regressions.
      
      This blindly pushes the BKL into all .open and .release
      operations for all block drivers to prepare for the
      next step. The drivers can subsequently replace the BKL
      with their own locks or remove it completely when it can
      be shown that it is not needed.
      
      The functions blkdev_get and blkdev_put are the only
      remaining users of the big kernel lock in the block
      layer, besides a few uses in the ioctl code, none
      of which need to serialize with blkdev_{get,put}.
      
      Most of these two functions is also under the protection
      of bdev->bd_mutex, including the actual calls to
      ->open and ->release, and the common code does not
      access any global data structures that need the BKL.
      Signed-off-by: NArnd Bergmann <arnd@arndb.de>
      Acked-by: NChristoph Hellwig <hch@infradead.org>
      Signed-off-by: NJens Axboe <jaxboe@fusionio.com>
      6e9624b8
    • C
      block: unify flags for struct bio and struct request · 7b6d91da
      Christoph Hellwig 提交于
      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: NChristoph Hellwig <hch@lst.de>
      Signed-off-by: NJens Axboe <jaxboe@fusionio.com>
      7b6d91da
  5. 26 7月, 2010 8 次提交
  6. 21 7月, 2010 1 次提交
  7. 24 6月, 2010 3 次提交
    • N
      md: Don't update ->recovery_offset when reshaping an array to fewer devices. · 70fffd0b
      NeilBrown 提交于
      When an array is reshaped to have fewer devices, the reshape proceeds
      from the end of the devices to the beginning.
      
      If a device happens to be non-In_sync (which is possible but rare)
      we would normally update the ->recovery_offset as the reshape
      progresses. However that would be wrong as the recover_offset records
      that the early part of the device is in_sync, while in fact it would
      only be the later part that is in_sync, and in any case the offset
      number would be measured from the wrong end of the device.
      
      Relatedly, if after a reshape a spare is discovered to not be
      recoverred all the way to the end, not allow spare_active
      to incorporate it in the array.
      
      This becomes relevant in the following sample scenario:
      
      A 4 drive RAID5 is converted to a 6 drive RAID6 in a combined
      operation.
      The RAID5->RAID6 conversion will cause a 5 drive to be included as a
      spare, then the 5drive -> 6drive reshape will effectively rebuild that
      spare as it progresses.  The 6th drive is treated as in_sync the whole
      time as there is never any case that we might consider reading from
      it, but must not because there is no valid data.
      
      If we interrupt this reshape part-way through and reverse it to return
      to a 5-drive RAID6 (or event a 4-drive RAID5), we don't want to update
      the recovery_offset - as that would be wrong - and we don't want to
      include that spare as active in the 5-drive RAID6 when the reversed
      reshape completed and it will be mostly out-of-sync still.
      Signed-off-by: NNeilBrown <neilb@suse.de>
      70fffd0b
    • N
      md: fix handling of array level takeover that re-arranges devices. · e93f68a1
      NeilBrown 提交于
      Most array level changes leave the list of devices largely unchanged,
      possibly causing one at the end to become redundant.
      However conversions between RAID0 and RAID10 need to renumber
      all devices (except 0).
      
      This renumbering is currently being done in the ->run method when the
      new personality takes over.  However this is too late as the common
      code in md.c might already have invalidated some of the devices if
      they had a ->raid_disk number that appeared to high.
      
      Moving it into the ->takeover method is too early as the array is
      still active at that time and wrong ->raid_disk numbers could cause
      confusion.
      
      So add a ->new_raid_disk field to mdk_rdev_s and use it to communicate
      the new raid_disk number.
      Now the common code knows exactly which devices need to be renumbered,
      and which can be invalidated, and can do it all at a convenient time
      when the array is suspend.
      It can also update some symlinks in sysfs which previously were not be
      updated correctly.
      Reported-by: NMaciej Trela <maciej.trela@intel.com>
      Signed-off-by: NNeilBrown <neilb@suse.de>
      e93f68a1
    • N
      Restore partition detection of newly created md arrays. · f3b99be1
      NeilBrown 提交于
      Commit  b821eaa5 broke partition
      detection for md arrays.
      
      The logic was almost right.  However if revalidate_disk is called
      when the device is not yet open, bdev->bd_disk won't be set, so the
      flush_disk() Call will not set bd_invalidated.
      
      So when md_open is called we still need to ensure that
      ->bd_invalidated gets set.  This is easily done with a call to
      check_disk_size_change in the place where the offending commit removed
      check_disk_change.  At the important times, the size will have changed
      from 0 to non-zero, so check_disk_size_change will set bd_invalidated.
      Tested-by: NDuncan <1i5t5.duncan@cox.net>
      Reported-by: NDuncan <1i5t5.duncan@cox.net>
      Signed-off-by: NNeilBrown <neilb@suse.de>
      f3b99be1
  8. 22 5月, 2010 1 次提交
    • E
      sysfs: Implement sysfs tagged directory support. · 3ff195b0
      Eric W. Biederman 提交于
      The problem.  When implementing a network namespace I need to be able
      to have multiple network devices with the same name.  Currently this
      is a problem for /sys/class/net/*, /sys/devices/virtual/net/*, and
      potentially a few other directories of the form /sys/ ... /net/*.
      
      What this patch does is to add an additional tag field to the
      sysfs dirent structure.  For directories that should show different
      contents depending on the context such as /sys/class/net/, and
      /sys/devices/virtual/net/ this tag field is used to specify the
      context in which those directories should be visible.  Effectively
      this is the same as creating multiple distinct directories with
      the same name but internally to sysfs the result is nicer.
      
      I am calling the concept of a single directory that looks like multiple
      directories all at the same path in the filesystem tagged directories.
      
      For the networking namespace the set of directories whose contents I need
      to filter with tags can depend on the presence or absence of hotplug
      hardware or which modules are currently loaded.  Which means I need
      a simple race free way to setup those directories as tagged.
      
      To achieve a reace free design all tagged directories are created
      and managed by sysfs itself.
      
      Users of this interface:
      - define a type in the sysfs_tag_type enumeration.
      - call sysfs_register_ns_types with the type and it's operations
      - sysfs_exit_ns when an individual tag is no longer valid
      
      - Implement mount_ns() which returns the ns of the calling process
        so we can attach it to a sysfs superblock.
      - Implement ktype.namespace() which returns the ns of a syfs kobject.
      
      Everything else is left up to sysfs and the driver layer.
      
      For the network namespace mount_ns and namespace() are essentially
      one line functions, and look to remain that.
      
      Tags are currently represented a const void * pointers as that is
      both generic, prevides enough information for equality comparisons,
      and is trivial to create for current users, as it is just the
      existing namespace pointer.
      
      The work needed in sysfs is more extensive.  At each directory
      or symlink creating I need to check if the directory it is being
      created in is a tagged directory and if so generate the appropriate
      tag to place on the sysfs_dirent.  Likewise at each symlink or
      directory removal I need to check if the sysfs directory it is
      being removed from is a tagged directory and if so figure out
      which tag goes along with the name I am deleting.
      
      Currently only directories which hold kobjects, and
      symlinks are supported.  There is not enough information
      in the current file attribute interfaces to give us anything
      to discriminate on which makes it useless, and there are
      no potential users which makes it an uninteresting problem
      to solve.
      Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
      Signed-off-by: NBenjamin Thery <benjamin.thery@bull.net>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
      3ff195b0
  9. 18 5月, 2010 17 次提交
    • N
      md: don't insist on valid event count for spare devices. · be6800a7
      NeilBrown 提交于
      Devices which know that they are spares do not really need to have
      an event count that matches the rest of the array, so there are no
      data-in-sync issues. It is enough that the uuid matches.
      So remove the requirement that the event count is up-to-date.
      
      We currently still write out and event count on spares, but this
      allows us in a year or 3 to stop doing that completely.
      Signed-off-by: NNeilBrown <neilb@suse.de>
      be6800a7
    • N
      md: simplify updating of event count to sometimes avoid updating spares. · a8707c08
      NeilBrown 提交于
      When updating the event count for a simple clean <-> dirty transition,
      we try to avoid updating the spares so they can safely spin-down.
      As the event_counts across an array must be +/- 1, this means
      decrementing the event_count on a dirty->clean transition.
      This is not always safe and we have to avoid the unsafe time.
      We current do this with a misguided idea about it being safe or
      not depending on whether the event_count is odd or even.  This
      approach only works reliably in a few common instances, but easily
      falls down.
      
      So instead, simply keep internal state concerning whether it is safe
      or not, and always assume it is not safe when an array is first
      assembled.
      Signed-off-by: NNeilBrown <neilb@suse.de>
      a8707c08
    • N
      md: restore ability of spare drives to spin down. · 75a73a29
      NeilBrown 提交于
      Some time ago we stopped the clean/active metadata updates
      from being written to a 'spare' device in most cases so that
      it could spin down and say spun down.  Device failure/removal
      etc are still recorded on spares.
      
      However commit 51d5668c broke this 50% of the time,
      depending on whether the event count is even or odd.
      The change log entry said:
      
         This means that the alignment between 'odd/even' and
          'clean/dirty' might take a little longer to attain,
      
      how ever the code makes no attempt to create that alignment, so it
      could take arbitrarily long.
      
      So when we find that clean/dirty is not aligned with odd/even,
      force a second metadata-update immediately.  There are already cases
      where a second metadata-update is needed immediately (e.g. when a
      device fails during the metadata update).  We just piggy-back on that.
      Reported-by: NJoe Bryant <tenminjoe@yahoo.com>
      Signed-off-by: NNeilBrown <neilb@suse.de>
      Cc: stable@kernel.org
      75a73a29
    • D
      md: allow integers to be passed to md/level · f2859af6
      Dan Williams 提交于
      e.g. allow md to interpret 'echo 4 > md/level' as a request for raid4.
      Signed-off-by: NDan Williams <dan.j.williams@intel.com>
      f2859af6
    • D
      md: notify mdstat waiters of level change · bb7f8d22
      Dan Williams 提交于
      Level modifications change the output of mdstat.  The mdmon manager
      thread is interested in these events for external metadata management.
      Signed-off-by: NDan Williams <dan.j.williams@intel.com>
      bb7f8d22
    • N
      md: don't unregister the thread in mddev_suspend · 9e35b99c
      NeilBrown 提交于
      This is
       - unnecessary because mddev_suspend is always followed by a call to
         ->stop, and each ->stop unregisters the thread, and
       - a problem as it makes it awkwards to suspend and then resume a
         device as we will want later.
      Signed-off-by: NNeilBrown <neilb@suse.de>
      9e35b99c
    • N
      md: factor out init code for an mddev · fafd7fb0
      NeilBrown 提交于
      This is a simple factorisation that makes mddev_find easier to read.
      Signed-off-by: NNeilBrown <neilb@suse.de>
      fafd7fb0
    • N
      md: pass mddev to make_request functions rather than request_queue · 21a52c6d
      NeilBrown 提交于
      We used to pass the personality make_request function direct
      to the block layer so the first argument had to be a queue.
      But now we have the intermediary md_make_request so it makes
      at lot more sense to pass a struct mddev_s.
      It makes it possible to have an mddev without its own queue too.
      Signed-off-by: NNeilBrown <neilb@suse.de>
      21a52c6d
    • N
      md: call md_stop_writes from md_stop · cca9cf90
      NeilBrown 提交于
      This moves the call to the other side of set_readonly, but that should
      not be an issue.
      This encapsulates in 'md_stop' all of the functionality for internally
      stopping the array, leaving all the interactions with externalities
      (sysfs, request_queue, gendisk) in do_md_stop.
      Signed-off-by: NNeilBrown <neilb@suse.de>
      cca9cf90
    • N
      md: split md_set_readonly out of do_md_stop · a4bd82d0
      NeilBrown 提交于
      Using do_md_stop to set an array to read-only is a little confusing.
      Now most of the common code has been factored out, split
      md_set_readonly off in to a separate function.
      Signed-off-by: NNeilBrown <neilb@suse.de>
      a4bd82d0
    • N
      md: factor md_stop_writes out of do_md_stop. · a047e125
      NeilBrown 提交于
      Further refactoring of do_md_stop.
      This one requires some explanation as it takes code from different
      places in do_md_stop, so some re-ordering happens.
      
      We only get into this part of do_md_stop if there are no active opens
      of the device, so no writes can be happening and the device must have
      been flushed.  In md_stop_writes we want to stop any internal sources
      of writes - i.e. resync - and flush out the metadata.
      
      The only code that was previously before some of this code is
      code to clean up the queue, the mddev, the gendisk, or sysfs, all
      of which is probably better after code that makes active changes (i.e.
      triggers writes).
      Signed-off-by: NNeilBrown <neilb@suse.de>
      a047e125
    • N
      md: start to refactor do_md_stop · 6177b472
      NeilBrown 提交于
      do_md_stop is large and clunky, so hard to understand.
      
      This is a first step of refactoring, pulling two simple
      sub-functions out.
      Signed-off-by: NNeilBrown <neilb@suse.de>
      6177b472
    • N
      md: factor do_md_run to separate accesses to ->gendisk · fe60b014
      NeilBrown 提交于
      As part of relaxing the binding between an mddev and gendisk,
      we separate do_md_run into two functions.
        md_run does all the work internal to md
        do_md_run calls md_run and makes and changes to gendisk
           that are required.
      Signed-off-by: NNeilBrown <neilb@suse.de>
      fe60b014
    • N
      md: remove ->changed and related code. · b821eaa5
      NeilBrown 提交于
      We set ->changed to 1 and call check_disk_change at the end
      of md_open so that bd_invalidated would be set and thus
      partition rescan would happen appropriately.
      
      Now that we call revalidate_disk directly, which sets bd_invalidates,
      that indirection is no longer needed and can be removed.
      Signed-off-by: NNeilBrown <neilb@suse.de>
      b821eaa5
    • N
      md: don't reference gendisk in getgeo · 49ce6cea
      NeilBrown 提交于
      Using ->array_sectors rather than get_capacity() is more
      direct and is a step towards relaxing the tight connection
      between mddev and gendisk.
      Signed-off-by: NNeilBrown <neilb@suse.de>
      49ce6cea
    • N
      md: move io accounting out of personalities into md_make_request · 49077326
      NeilBrown 提交于
      While I generally prefer letting personalities do as much as possible,
      given that we have a central md_make_request anyway we may as well use
      it to simplify code.
      Also this centralises knowledge of ->gendisk which will help later.
      Signed-off-by: NNeilBrown <neilb@suse.de>
      49077326
    • M
      md: notify level changes through sysfs. · 5cac7861
      Maciej Trela 提交于
      Level changes can be very significant, so make sure
      to notify them via sysfs.
      Signed-off-by: NMaciej Trela <maciej.trela@intel.com>
      Signed-off-by: NNeilBrown <neilb@suse.de>
      5cac7861