blk: centralize non-request unplug handling.
Both md and umem has similar code for getting notified on an
blk_finish_plug event.
Centralize this code in block/ and allow each driver to
provide its distinctive difference.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/drivers/block/umem.c b/drivers/block/umem.c
index 9a72277..6ef3489 100644
--- a/drivers/block/umem.c
+++ b/drivers/block/umem.c
@@ -513,42 +513,19 @@
}
}
-struct mm_plug_cb {
- struct blk_plug_cb cb;
- struct cardinfo *card;
-};
-
static void mm_unplug(struct blk_plug_cb *cb)
{
- struct mm_plug_cb *mmcb = container_of(cb, struct mm_plug_cb, cb);
+ struct cardinfo *card = cb->data;
- spin_lock_irq(&mmcb->card->lock);
- activate(mmcb->card);
- spin_unlock_irq(&mmcb->card->lock);
- kfree(mmcb);
+ spin_lock_irq(&card->lock);
+ activate(card);
+ spin_unlock_irq(&card->lock);
+ kfree(cb);
}
static int mm_check_plugged(struct cardinfo *card)
{
- struct blk_plug *plug = current->plug;
- struct mm_plug_cb *mmcb;
-
- if (!plug)
- return 0;
-
- list_for_each_entry(mmcb, &plug->cb_list, cb.list) {
- if (mmcb->cb.callback == mm_unplug && mmcb->card == card)
- return 1;
- }
- /* Not currently on the callback list */
- mmcb = kmalloc(sizeof(*mmcb), GFP_ATOMIC);
- if (!mmcb)
- return 0;
-
- mmcb->card = card;
- mmcb->cb.callback = mm_unplug;
- list_add(&mmcb->cb.list, &plug->cb_list);
- return 1;
+ return !!blk_check_plugged(mm_unplug, card, sizeof(struct blk_plug_cb));
}
static void mm_make_request(struct request_queue *q, struct bio *bio)