Merge branch 'for-3.6/drivers' of git://git.kernel.dk/linux-block

[karo-tx-linux.git] / drivers / md / md.c

diff --git a/drivers/md/md.c b/drivers/md/md.c
index d5ab4493c8be656ecd28227994d7f7bbe06b8e2d..fcd098794d37d16c7b48b12c54b5ba6f5e6ba60e 100644 (file)
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -498,61 +498,13 @@ void md_flush_request(struct mddev *mddev, struct bio *bio)
 }
 EXPORT_SYMBOL(md_flush_request);
 
-/* Support for plugging.
- * This mirrors the plugging support in request_queue, but does not
- * require having a whole queue or request structures.
- * We allocate an md_plug_cb for each md device and each thread it gets
- * plugged on.  This links tot the private plug_handle structure in the
- * personality data where we keep a count of the number of outstanding
- * plugs so other code can see if a plug is active.
- */
-struct md_plug_cb {
-       struct blk_plug_cb cb;
-       struct mddev *mddev;
-};
-
-static void plugger_unplug(struct blk_plug_cb *cb)
-{
-       struct md_plug_cb *mdcb = container_of(cb, struct md_plug_cb, cb);
-       if (atomic_dec_and_test(&mdcb->mddev->plug_cnt))
-               md_wakeup_thread(mdcb->mddev->thread);
-       kfree(mdcb);
-}
-
-/* Check that an unplug wakeup will come shortly.
- * If not, wakeup the md thread immediately
- */
-int mddev_check_plugged(struct mddev *mddev)
+void md_unplug(struct blk_plug_cb *cb, bool from_schedule)
 {
-       struct blk_plug *plug = current->plug;
-       struct md_plug_cb *mdcb;
-
-       if (!plug)
-               return 0;
-
-       list_for_each_entry(mdcb, &plug->cb_list, cb.list) {
-               if (mdcb->cb.callback == plugger_unplug &&
-                   mdcb->mddev == mddev) {
-                       /* Already on the list, move to top */
-                       if (mdcb != list_first_entry(&plug->cb_list,
-                                                   struct md_plug_cb,
-                                                   cb.list))
-                               list_move(&mdcb->cb.list, &plug->cb_list);
-                       return 1;
-               }
-       }
-       /* Not currently on the callback list */
-       mdcb = kmalloc(sizeof(*mdcb), GFP_ATOMIC);
-       if (!mdcb)
-               return 0;
-
-       mdcb->mddev = mddev;
-       mdcb->cb.callback = plugger_unplug;
-       atomic_inc(&mddev->plug_cnt);
-       list_add(&mdcb->cb.list, &plug->cb_list);
-       return 1;
+       struct mddev *mddev = cb->data;
+       md_wakeup_thread(mddev->thread);
+       kfree(cb);
 }
-EXPORT_SYMBOL_GPL(mddev_check_plugged);
+EXPORT_SYMBOL(md_unplug);
 
 static inline struct mddev *mddev_get(struct mddev *mddev)
 {
@@ -602,7 +554,6 @@ void mddev_init(struct mddev *mddev)
        atomic_set(&mddev->active, 1);
        atomic_set(&mddev->openers, 0);
        atomic_set(&mddev->active_io, 0);
-       atomic_set(&mddev->plug_cnt, 0);
        spin_lock_init(&mddev->write_lock);
        atomic_set(&mddev->flush_pending, 0);
        init_waitqueue_head(&mddev->sb_wait);
@@ -3942,17 +3893,13 @@ array_state_store(struct mddev *mddev, const char *buf, size_t len)
                break;
        case clear:
                /* stopping an active array */
-               if (atomic_read(&mddev->openers) > 0)
-                       return -EBUSY;
                err = do_md_stop(mddev, 0, NULL);
                break;
        case inactive:
                /* stopping an active array */
-               if (mddev->pers) {
-                       if (atomic_read(&mddev->openers) > 0)
-                               return -EBUSY;
+               if (mddev->pers)
                        err = do_md_stop(mddev, 2, NULL);
-               } else
+               else
                        err = 0; /* already inactive */
                break;
        case suspended: