Fix up comments about matching flags between bio and rq

[mv-sheeva.git] / block / blk-core.c

diff --git a/block/blk-core.c b/block/blk-core.c
index fef79ccb2a118da2f6f3144c993c8338c7205351..a496727df7ef4b1b4016f961d6350e279677afc9 100644 (file)
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -212,6 +212,24 @@ void blk_plug_device(struct request_queue *q)
 }
 EXPORT_SYMBOL(blk_plug_device);
 
+/**
+ * blk_plug_device_unlocked - plug a device without queue lock held
+ * @q:    The &struct request_queue to plug
+ *
+ * Description:
+ *   Like @blk_plug_device(), but grabs the queue lock and disables
+ *   interrupts.
+ **/
+void blk_plug_device_unlocked(struct request_queue *q)
+{
+       unsigned long flags;
+
+       spin_lock_irqsave(q->queue_lock, flags);
+       blk_plug_device(q);
+       spin_unlock_irqrestore(q->queue_lock, flags);
+}
+EXPORT_SYMBOL(blk_plug_device_unlocked);
+
 /*
  * remove the queue from the plugged list, if present. called with
  * queue lock held and interrupts disabled.
@@ -564,6 +582,8 @@ blk_init_queue_node(request_fn_proc *rfn, spinlock_t *lock, int node_id)
 
        q->sg_reserved_size = INT_MAX;
 
+       blk_set_cmd_filter_defaults(&q->cmd_filter);
+
        /*
         * all done
         */
@@ -604,10 +624,6 @@ blk_alloc_request(struct request_queue *q, int rw, int priv, gfp_t gfp_mask)
 
        blk_rq_init(q, rq);
 
-       /*
-        * first three bits are identical in rq->cmd_flags and bio->bi_rw,
-        * see bio.h and blkdev.h
-        */
        rq->cmd_flags = rw | REQ_ALLOCED;
 
        if (priv) {
@@ -1470,10 +1486,7 @@ void submit_bio(int rw, struct bio *bio)
         * If it's a regular read/write or a barrier with data attached,
         * go through the normal accounting stuff before submission.
         */
-       if (!bio_empty_barrier(bio)) {
-
-               BIO_BUG_ON(!bio->bi_size);
-               BIO_BUG_ON(!bio->bi_io_vec);
+       if (bio_has_data(bio)) {
 
                if (rw & WRITE) {
                        count_vm_events(PGPGOUT, count);
@@ -1868,7 +1881,7 @@ static int blk_end_io(struct request *rq, int error, unsigned int nr_bytes,
        struct request_queue *q = rq->q;
        unsigned long flags = 0UL;
 
-       if (blk_fs_request(rq) || blk_pc_request(rq)) {
+       if (bio_has_data(rq->bio)) {
                if (__end_that_request_first(rq, error, nr_bytes))
                        return 1;
 
@@ -1926,10 +1939,9 @@ EXPORT_SYMBOL_GPL(blk_end_request);
  **/
 int __blk_end_request(struct request *rq, int error, unsigned int nr_bytes)
 {
-       if (blk_fs_request(rq) || blk_pc_request(rq)) {
-               if (__end_that_request_first(rq, error, nr_bytes))
-                       return 1;
-       }
+       if (bio_has_data(rq->bio) &&
+           __end_that_request_first(rq, error, nr_bytes))
+               return 1;
 
        add_disk_randomness(rq->rq_disk);
 
@@ -1996,7 +2008,8 @@ EXPORT_SYMBOL_GPL(blk_end_request_callback);
 void blk_rq_bio_prep(struct request_queue *q, struct request *rq,
                     struct bio *bio)
 {
-       /* first two bits are identical in rq->cmd_flags and bio->bi_rw */
+       /* Bit 0 (R/W) is identical in rq->cmd_flags and bio->bi_rw, and
+          we want BIO_RW_AHEAD (bit 1) to imply REQ_FAILFAST (bit 1). */
        rq->cmd_flags |= (bio->bi_rw & 3);
 
        rq->nr_phys_segments = bio_phys_segments(q, bio);