diff options
-rw-r--r-- | block/ll_rw_blk.c | 14 |
1 files changed, 13 insertions, 1 deletions
diff --git a/block/ll_rw_blk.c b/block/ll_rw_blk.c index fb8fb88..de5ba47 100644 --- a/block/ll_rw_blk.c +++ b/block/ll_rw_blk.c @@ -1351,8 +1351,20 @@ int blk_rq_map_sg(struct request_queue *q, struct request *rq, new_segment: if (!sg) sg = sglist; - else + else { + /* + * If the driver previously mapped a shorter + * list, we could see a termination bit + * prematurely unless it fully inits the sg + * table on each mapping. We KNOW that there + * must be more entries here or the driver + * would be buggy, so force clear the + * termination bit to avoid doing a full + * sg_init_table() in drivers for each command. + */ + sg->page_link &= ~0x02; sg = sg_next(sg); + } sg_set_page(sg, bvec->bv_page); sg->length = nbytes; |