target: avoid accessing .bi_vcnt directly

When the bio is full, bio_add_pc_page() will return zero,
so use this information tell when the bio is full.

Also replace access to .bi_vcnt for pr_debug() with bio_segments().

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@fb.com>

diff --git a/drivers/target/target_core_pscsi.c b/drivers/target/target_core_pscsi.c
index 9125d93..04d7aa7 100644 (file)
--- a/drivers/target/target_core_pscsi.c
+++ b/drivers/target/target_core_pscsi.c
@@ -935,13 +935,9 @@ pscsi_map_sg(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
 
                        rc = bio_add_pc_page(pdv->pdv_sd->request_queue,
                                        bio, page, bytes, off);
-                       if (rc != bytes)
-                               goto fail;
-
                        pr_debug("PSCSI: bio->bi_vcnt: %d nr_vecs: %d\n",
-                               bio->bi_vcnt, nr_vecs);
-
-                       if (bio->bi_vcnt > nr_vecs) {
+                               bio_segments(bio), nr_vecs);
+                       if (rc != bytes) {
                                pr_debug("PSCSI: Reached bio->bi_vcnt max:"
                                        " %d i: %d bio: %p, allocating another"
                                        " bio\n", bio->bi_vcnt, i, bio);