This patch adds comment on usage of bio_alloc_pages(). Signed-off-by: Ming Lei <ming.lei@xxxxxxxxxx> --- block/bio.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/block/bio.c b/block/bio.c index e241bbc49f14..826b5d173416 100644 --- a/block/bio.c +++ b/block/bio.c @@ -981,7 +981,9 @@ EXPORT_SYMBOL(bio_advance); * @bio: bio to allocate pages for * @gfp_mask: flags for allocation * - * Allocates pages up to @bio->bi_vcnt. + * Allocates pages up to @bio->bi_vcnt, and this function should only + * be called on a new initialized bio, which means all pages aren't added + * to the bio via bio_add_page() yet. * * Returns 0 on success, -ENOMEM on failure. On failure, any allocated pages are * freed. -- 2.9.4
