1. 03 Mar, 2011 2 commits
    • Vivek Goyal's avatar
      loop: No need to initialize ->queue_lock explicitly before calling blk_cleanup_queue() · cd25f549
      Vivek Goyal authored
      Now we initialize ->queue_lock at queue allocation time so driver does
      not have to worry about initializing it before calling
      blk_cleanup_queue().
      Signed-off-by: default avatarJens Axboe <jaxboe@fusionio.com>
      cd25f549
    • Vivek Goyal's avatar
      block: Initialize ->queue_lock to internal lock at queue allocation time · c94a96ac
      Vivek Goyal authored
      There does not seem to be a clear convention whether q->queue_lock is
      initialized or not when blk_cleanup_queue() is called. In the past it
      was not necessary but now blk_throtl_exit() takes up queue lock by
      default and needs queue lock to be available.
      
      In fact elevator_exit() code also has similar requirement just that it
      is less stringent in the sense that elevator_exit() is called only if
      elevator is initialized.
      
      Two problems have been noticed because of ambiguity about spin lock
      status.
      
            - If a driver calls blk_alloc_queue() and then soon calls
              blk_cleanup_queue() almost immediately, (because some other
      	driver structure allocation failed or some other error happened)
      	then blk_throtl_exit() will run into issues as queue lock is not
      	initialized. Loop driver ran into this issue recently and I
      	noticed error paths in md driver too. Similar error paths should
      	exist in other drivers too.
      
            - If some driver provided external spin lock and zapped the lock
              before blk_cleanup_queue(), then it can lead to issues.
      
      So this patch initializes the default queue lock at queue allocation time.
      
      block throttling code is one of the users of queue lock and it is
      initialized at the queue allocation time, so it makes sense to
      initialize ->queue_lock also to internal lock. A driver can overide that
      lock later. This will take care of the issue where a driver does not have
      to worry about initializing the queue lock to default before calling
      blk_cleanup_queue()
      Signed-off-by: default avatarVivek Goyal <vgoyal@redhat.com>
      Signed-off-by: default avatarJens Axboe <jaxboe@fusionio.com>
      c94a96ac
  2. 02 Mar, 2011 1 commit
  3. 01 Mar, 2011 2 commits
  4. 22 Feb, 2011 2 commits
  5. 21 Feb, 2011 33 commits