nvme-tcp: pass multipage bvec to request iov_iter

iov_iter uses the right helpers so we should be able
to pass in a multipage bvec. Right now the iov_iter is
initialized with more segments that it needs which doesn't
fail because the iov_iter is capped by byte count, but it
is better to use a full multipage bvec iter.

Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>

diff --git a/drivers/nvme/host/tcp.c b/drivers/nvme/host/tcp.c
index f2f3471..4c13c71 100644 (file)
--- a/drivers/nvme/host/tcp.c
+++ b/drivers/nvme/host/tcp.c
@@ -224,24 +224,29 @@ static void nvme_tcp_init_iter(struct nvme_tcp_request *req,
        struct request *rq = blk_mq_rq_from_pdu(req);
        struct bio_vec *vec;
        unsigned int size;
-       int nsegs;
+       int nr_bvec;
        size_t offset;
 
        if (rq->rq_flags & RQF_SPECIAL_PAYLOAD) {
                vec = &rq->special_vec;
-               nsegs = 1;
+               nr_bvec = 1;
                size = blk_rq_payload_bytes(rq);
                offset = 0;
        } else {
                struct bio *bio = req->curr_bio;
+               struct bvec_iter bi;
+               struct bio_vec bv;
 
                vec = __bvec_iter_bvec(bio->bi_io_vec, bio->bi_iter);
-               nsegs = bio_segments(bio);
+               nr_bvec = 0;
+               bio_for_each_bvec(bv, bio, bi) {
+                       nr_bvec++;
+               }
                size = bio->bi_iter.bi_size;
                offset = bio->bi_iter.bi_bvec_done;
        }
 
-       iov_iter_bvec(&req->iter, dir, vec, nsegs, size);
+       iov_iter_bvec(&req->iter, dir, vec, nr_bvec, size);
        req->iter.iov_offset = offset;
 }