Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm...

[sfrench/cifs-2.6.git] / block / blk-map.c

diff --git a/block/blk-map.c b/block/blk-map.c
index b21f8e86f1207f9b76bf3e2083fcf72b5062f0b7..d3a94719f03fb2af81d6270d6fc9ed58f0dde373 100644 (file)
--- a/block/blk-map.c
+++ b/block/blk-map.c
@@ -12,22 +12,29 @@
 #include "blk.h"
 
 /*
- * Append a bio to a passthrough request.  Only works can be merged into
- * the request based on the driver constraints.
+ * Append a bio to a passthrough request.  Only works if the bio can be merged
+ * into the request based on the driver constraints.
  */
-int blk_rq_append_bio(struct request *rq, struct bio *bio)
+int blk_rq_append_bio(struct request *rq, struct bio **bio)
 {
-       blk_queue_bounce(rq->q, &bio);
+       struct bio *orig_bio = *bio;
+
+       blk_queue_bounce(rq->q, bio);
 
        if (!rq->bio) {
-               blk_rq_bio_prep(rq->q, rq, bio);
+               blk_rq_bio_prep(rq->q, rq, *bio);
        } else {
-               if (!ll_back_merge_fn(rq->q, rq, bio))
+               if (!ll_back_merge_fn(rq->q, rq, *bio)) {
+                       if (orig_bio != *bio) {
+                               bio_put(*bio);
+                               *bio = orig_bio;
+                       }
                        return -EINVAL;
+               }
 
-               rq->biotail->bi_next = bio;
-               rq->biotail = bio;
-               rq->__data_len += bio->bi_iter.bi_size;
+               rq->biotail->bi_next = *bio;
+               rq->biotail = *bio;
+               rq->__data_len += (*bio)->bi_iter.bi_size;
        }
 
        return 0;
@@ -73,14 +80,12 @@ static int __blk_rq_map_user_iov(struct request *rq,
         * We link the bounce buffer in and could have to traverse it
         * later so we have to get a ref to prevent it from being freed
         */
-       ret = blk_rq_append_bio(rq, bio);
-       bio_get(bio);
+       ret = blk_rq_append_bio(rq, &bio);
        if (ret) {
-               bio_endio(bio);
                __blk_rq_unmap_user(orig_bio);
-               bio_put(bio);
                return ret;
        }
+       bio_get(bio);
 
        return 0;
 }
@@ -213,7 +218,7 @@ int blk_rq_map_kern(struct request_queue *q, struct request *rq, void *kbuf,
        int reading = rq_data_dir(rq) == READ;
        unsigned long addr = (unsigned long) kbuf;
        int do_copy = 0;
-       struct bio *bio;
+       struct bio *bio, *orig_bio;
        int ret;
 
        if (len > (queue_max_hw_sectors(q) << 9))
@@ -236,10 +241,11 @@ int blk_rq_map_kern(struct request_queue *q, struct request *rq, void *kbuf,
        if (do_copy)
                rq->rq_flags |= RQF_COPY_USER;
 
-       ret = blk_rq_append_bio(rq, bio);
+       orig_bio = bio;
+       ret = blk_rq_append_bio(rq, &bio);
        if (unlikely(ret)) {
                /* request is too big */
-               bio_put(bio);
+               bio_put(orig_bio);
                return ret;
        }