UBUNTU: Ubuntu-2.6.38-12.51

[linux-flexiantxendom0-natty.git] / block / blk-core.c

diff --git a/block/blk-core.c b/block/blk-core.c
index 3689319..518dd42 100644 (file)
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -64,13 +64,27 @@ static void drive_stat_acct(struct request *rq, int new_io)
                return;
 
        cpu = part_stat_lock();
-       part = disk_map_sector_rcu(rq->rq_disk, blk_rq_pos(rq));
 
-       if (!new_io)
+       if (!new_io) {
+               part = rq->part;
                part_stat_inc(cpu, part, merges[rw]);
-       else {
+       } else {
+               part = disk_map_sector_rcu(rq->rq_disk, blk_rq_pos(rq));
+               if (!hd_struct_try_get(part)) {
+                       /*
+                        * The partition is already being removed,
+                        * the request will be accounted on the disk only
+                        *
+                        * We take a reference on disk->part0 although that
+                        * partition will never be deleted, so we can treat
+                        * it as any other partition.
+                        */
+                       part = &rq->rq_disk->part0;
+                       hd_struct_get(part);
+               }
                part_round_stats(cpu, part);
                part_inc_in_flight(part, rw);
+               rq->part = part;
        }
 
        part_stat_unlock();
@@ -128,6 +142,7 @@ void blk_rq_init(struct request_queue *q, struct request *rq)
        rq->ref_count = 1;
        rq->start_time = jiffies;
        set_start_time_ns(rq);
+       rq->part = NULL;
 }
 EXPORT_SYMBOL(blk_rq_init);
 
@@ -337,7 +352,7 @@ void blk_start_queue(struct request_queue *q)
        WARN_ON(!irqs_disabled());
 
        queue_flag_clear(QUEUE_FLAG_STOPPED, q);
-       __blk_run_queue(q);
+       __blk_run_queue(q, false);
 }
 EXPORT_SYMBOL(blk_start_queue);
 
@@ -388,13 +403,14 @@ EXPORT_SYMBOL(blk_sync_queue);
 /**
  * __blk_run_queue - run a single device queue
  * @q: The queue to run
+ * @force_kblockd: Don't run @q->request_fn directly.  Use kblockd.
  *
  * Description:
  *    See @blk_run_queue. This variant must be called with the queue lock
  *    held and interrupts disabled.
  *
  */
-void __blk_run_queue(struct request_queue *q)
+void __blk_run_queue(struct request_queue *q, bool force_kblockd)
 {
        blk_remove_plug(q);
 
@@ -408,7 +424,7 @@ void __blk_run_queue(struct request_queue *q)
         * Only recurse once to avoid overrunning the stack, let the unplug
         * handling reinvoke the handler shortly if we already got there.
         */
-       if (!queue_flag_test_and_set(QUEUE_FLAG_REENTER, q)) {
+       if (!force_kblockd && !queue_flag_test_and_set(QUEUE_FLAG_REENTER, q)) {
                q->request_fn(q);
                queue_flag_clear(QUEUE_FLAG_REENTER, q);
        } else {
@@ -431,7 +447,7 @@ void blk_run_queue(struct request_queue *q)
        unsigned long flags;
 
        spin_lock_irqsave(q->queue_lock, flags);
-       __blk_run_queue(q);
+       __blk_run_queue(q, false);
        spin_unlock_irqrestore(q->queue_lock, flags);
 }
 EXPORT_SYMBOL(blk_run_queue);
@@ -1038,7 +1054,7 @@ void blk_insert_request(struct request_queue *q, struct request *rq,
 
        drive_stat_acct(rq, 1);
        __elv_add_request(q, rq, where, 0);
-       __blk_run_queue(q);
+       __blk_run_queue(q, false);
        spin_unlock_irqrestore(q->queue_lock, flags);
 }
 EXPORT_SYMBOL(blk_insert_request);
@@ -1776,7 +1792,7 @@ static void blk_account_io_completion(struct request *req, unsigned int bytes)
                int cpu;
 
                cpu = part_stat_lock();
-               part = disk_map_sector_rcu(req->rq_disk, blk_rq_pos(req));
+               part = req->part;
                part_stat_add(cpu, part, sectors[rw], bytes >> 9);
                part_stat_unlock();
        }
@@ -1796,13 +1812,14 @@ static void blk_account_io_done(struct request *req)
                int cpu;
 
                cpu = part_stat_lock();
-               part = disk_map_sector_rcu(req->rq_disk, blk_rq_pos(req));
+               part = req->part;
 
                part_stat_inc(cpu, part, ios[rw]);
                part_stat_add(cpu, part, ticks[rw], duration);
                part_round_stats(cpu, part);
                part_dec_in_flight(part, rw);
 
+               hd_struct_put(part);
                part_stat_unlock();
        }
 }
@@ -2594,13 +2611,6 @@ int kblockd_schedule_work(struct request_queue *q, struct work_struct *work)
 }
 EXPORT_SYMBOL(kblockd_schedule_work);
 
-int kblockd_schedule_delayed_work(struct request_queue *q,
-                       struct delayed_work *dwork, unsigned long delay)
-{
-       return queue_delayed_work(kblockd_workqueue, dwork, delay);
-}
-EXPORT_SYMBOL(kblockd_schedule_delayed_work);
-
 int __init blk_dev_init(void)
 {
        BUILD_BUG_ON(__REQ_NR_BITS > 8 *