[SCSI] block: fix the partial mappings with struct rq_map_data
This fixes bio_copy_user_iov to properly handle the partial mappings
with struct rq_map_data (which only sg uses for now but st and osst
will shortly). It adds the offset member to struct rq_map_data and
changes blk_rq_map_user to update it so that bio_copy_user_iov can add
an appropriate page frame via bio_add_pc_page().
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
diff --git a/block/blk-map.c b/block/blk-map.c
index 2990447..c7e55b2 100644
--- a/block/blk-map.c
+++ b/block/blk-map.c
@@ -150,6 +150,9 @@
bio = rq->bio;
bytes_read += ret;
ubuf += ret;
+
+ if (map_data)
+ map_data->offset += ret;
}
if (!bio_flagged(bio, BIO_USER_MAPPED))
