From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qk0-f200.google.com (mail-qk0-f200.google.com [209.85.220.200]) by kanga.kvack.org (Postfix) with ESMTP id 371A06B0311 for ; Tue, 8 Aug 2017 04:47:38 -0400 (EDT) Received: by mail-qk0-f200.google.com with SMTP id k126so12957873qke.8 for ; Tue, 08 Aug 2017 01:47:38 -0700 (PDT) Received: from mx1.redhat.com (mx1.redhat.com. [209.132.183.28]) by mx.google.com with ESMTPS id v25si780847qtf.254.2017.08.08.01.47.37 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 08 Aug 2017 01:47:37 -0700 (PDT) From: Ming Lei Subject: [PATCH v3 08/49] block: comment on bio_alloc_pages() Date: Tue, 8 Aug 2017 16:45:07 +0800 Message-Id: <20170808084548.18963-9-ming.lei@redhat.com> In-Reply-To: <20170808084548.18963-1-ming.lei@redhat.com> References: <20170808084548.18963-1-ming.lei@redhat.com> Sender: owner-linux-mm@kvack.org List-ID: To: Jens Axboe , Christoph Hellwig , Huang Ying , Andrew Morton , Alexander Viro Cc: linux-kernel@vger.kernel.org, linux-block@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, Ming Lei This patch adds comment on usage of bio_alloc_pages(). Signed-off-by: Ming Lei --- 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 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org