block: mark 1st parameter of bvec_iter_advance as const

bvec_iter_advance() only writes the parameter of iterator,
so the base address of bvec can be marked as const safely.

Without the change, we can see compiling warning in the
following patch for implementing iterate_bvec(): lib/iov_iter.c
with bvec iterator.

Reviewed-by: Christoph Hellwig <[email protected]>
Signed-off-by: Ming Lei <[email protected]>
Tested-by: Hannes Reinecke <[email protected]>
Signed-off-by: Jens Axboe <[email protected]>

diff --git a/include/linux/bvec.h b/include/linux/bvec.h
index 096efd2c83e5b3ac58b004aaaf936f54d70cf6af..701b64a3b7c5e3e94b0487f0ec73801d06715817 100644 (file)
--- a/include/linux/bvec.h
+++ b/include/linux/bvec.h
@@ -66,7 +66,8 @@ struct bvec_iter {
        .bv_offset      = bvec_iter_offset((bvec), (iter)),     \
 })
 
-static inline void bvec_iter_advance(struct bio_vec *bv, struct bvec_iter *iter,
+static inline void bvec_iter_advance(const struct bio_vec *bv,
+                                    struct bvec_iter *iter,
                                     unsigned bytes)
 {
        WARN_ONCE(bytes > iter->bi_size,