- /*
- * __blk_rq_map_user() copies the buffers if starting address
- * or length isn't aligned. As the copied buffer is always
- * page aligned, we know that there's enough room for padding.
- * Extend the last bio and update rq->data_len accordingly.
- *
- * On unmap, bio_uncopy_user() will use unmodified
- * bio_map_data pointed to by bio->bi_private.
- */
- if (len & queue_dma_alignment(q)) {
- unsigned int pad_len = (queue_dma_alignment(q) & ~len) + 1;
- struct bio *bio = rq->biotail;
-
- bio->bi_io_vec[bio->bi_vcnt - 1].bv_len += pad_len;
- bio->bi_size += pad_len;
- rq->data_len += pad_len;
- }
+ if (!bio_flagged(bio, BIO_USER_MAPPED))
+ rq->cmd_flags |= REQ_COPY_USER;