block: Initial support for data-less (or empty) barrier support

[deliverable/linux.git] / include / linux / blkdev.h

diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index a1c96d9ee720c1032217a1aa4e06d6d31799eab2..fb2ff749dc1f3edc2e5aaaaf0c7abf3dab807268 100644 (file)
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -1,6 +1,8 @@
 #ifndef _LINUX_BLKDEV_H
 #define _LINUX_BLKDEV_H
 
+#ifdef CONFIG_BLOCK
+
 #include <linux/sched.h>
 #include <linux/major.h>
 #include <linux/genhd.h>
@@ -18,22 +20,6 @@
 
 #include <asm/scatterlist.h>
 
-#ifdef CONFIG_LBD
-# include <asm/div64.h>
-# define sector_div(a, b) do_div(a, b)
-#else
-# define sector_div(n, b)( \
-{ \
-       int _res; \
-       _res = (n) % (b); \
-       (n) /= (b); \
-       _res; \
-} \
-)
-#endif
-
-#ifdef CONFIG_BLOCK
-
 struct scsi_ioctl_command;
 
 struct request_queue;
@@ -471,7 +457,6 @@ struct request_queue
        int                     orderr, ordcolor;
        struct request          pre_flush_rq, bar_rq, post_flush_rq;
        struct request          *orig_bar_rq;
-       unsigned int            bi_size;
 
        struct mutex            sysfs_lock;
 
@@ -483,8 +468,8 @@ struct request_queue
 #define QUEUE_FLAG_CLUSTER     0       /* cluster several segments into 1 */
 #define QUEUE_FLAG_QUEUED      1       /* uses generic tag queueing */
 #define QUEUE_FLAG_STOPPED     2       /* queue is stopped */
-#define        QUEUE_FLAG_READFULL     3       /* write queue has been filled */
-#define QUEUE_FLAG_WRITEFULL   4       /* read queue has been filled */
+#define        QUEUE_FLAG_READFULL     3       /* read queue has been filled */
+#define QUEUE_FLAG_WRITEFULL   4       /* write queue has been filled */
 #define QUEUE_FLAG_DEAD                5       /* queue being torn down */
 #define QUEUE_FLAG_REENTER     6       /* Re-entrancy avoidance */
 #define QUEUE_FLAG_PLUGGED     7       /* queue is plugged */
@@ -555,6 +540,7 @@ enum {
 #define blk_barrier_rq(rq)     ((rq)->cmd_flags & REQ_HARDBARRIER)
 #define blk_fua_rq(rq)         ((rq)->cmd_flags & REQ_FUA)
 #define blk_bidi_rq(rq)                ((rq)->next_rq != NULL)
+#define blk_empty_barrier(rq)  (blk_barrier_rq(rq) && blk_fs_request(rq) && !(rq)->hard_nr_sectors)
 
 #define list_entry_rq(ptr)     list_entry((ptr), struct request, queuelist)
 
@@ -637,10 +623,23 @@ static inline void blk_queue_bounce(struct request_queue *q, struct bio **bio)
 }
 #endif /* CONFIG_MMU */
 
-#define rq_for_each_bio(_bio, rq)      \
+struct req_iterator {
+       int i;
+       struct bio *bio;
+};
+
+/* This should not be used directly - use rq_for_each_segment */
+#define __rq_for_each_bio(_bio, rq)    \
        if ((rq->bio))                  \
                for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next)
 
+#define rq_for_each_segment(bvl, _rq, _iter)                   \
+       __rq_for_each_bio(_iter.bio, _rq)                       \
+               bio_for_each_segment(bvl, _iter.bio, _iter.i)
+
+#define rq_iter_last(rq, _iter)                                        \
+               (_iter.bio->bi_next == NULL && _iter.i == _iter.bio->bi_vcnt-1)
+
 extern int blk_register_queue(struct gendisk *disk);
 extern void blk_unregister_queue(struct gendisk *disk);
 extern void register_disk(struct gendisk *dev);
@@ -662,8 +661,8 @@ extern int sg_scsi_ioctl(struct file *, struct request_queue *,
 /*
  * Temporary export, until SCSI gets fixed up.
  */
-extern int ll_back_merge_fn(struct request_queue *, struct request *,
-               struct bio *);
+extern int blk_rq_append_bio(struct request_queue *q, struct request *rq,
+                            struct bio *bio);
 
 /*
  * A queue has just exitted congestion.  Note this in the global counter of
@@ -731,7 +730,9 @@ static inline void blk_run_address_space(struct address_space *mapping)
 extern int end_that_request_first(struct request *, int, int);
 extern int end_that_request_chunk(struct request *, int, int);
 extern void end_that_request_last(struct request *, int);
-extern void end_request(struct request *req, int uptodate);
+extern void end_request(struct request *, int);
+extern void end_queued_request(struct request *, int);
+extern void end_dequeued_request(struct request *, int);
 extern void blk_complete_request(struct request *);
 
 /*
@@ -810,7 +811,6 @@ static inline struct request *blk_map_queue_find_tag(struct blk_queue_tag *bqt,
        return bqt->tag_index[tag];
 }
 
-extern void blk_rq_bio_prep(struct request_queue *, struct request *, struct bio *);
 extern int blkdev_issue_flush(struct block_device *, sector_t *);
 
 #define MAX_PHYS_SEGMENTS 128