Introduce rq_for_each_segment replacing rq_for_each_bio
Every usage of rq_for_each_bio wraps a usage of
bio_for_each_segment, so these can be combined into
rq_for_each_segment.
We define "struct req_iterator" to hold the 'bio' and 'index' that
are needed for the double iteration.
Signed-off-by: Neil Brown <neilb@suse.de>
Various compile fixes by me...
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index b126c6f..a4b13b8 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -637,10 +637,23 @@
}
#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);