From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Ming Lei 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 Subject: [PATCH v2 02/51] block: loop: comment on direct access to bvec table Date: Mon, 26 Jun 2017 20:09:45 +0800 Message-Id: <20170626121034.3051-3-ming.lei@redhat.com> In-Reply-To: <20170626121034.3051-1-ming.lei@redhat.com> References: <20170626121034.3051-1-ming.lei@redhat.com> Sender: owner-linux-mm@kvack.org List-ID: Signed-off-by: Ming Lei --- drivers/block/loop.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/block/loop.c b/drivers/block/loop.c index 0de11444e317..88063ab17e9a 100644 --- a/drivers/block/loop.c +++ b/drivers/block/loop.c @@ -487,6 +487,11 @@ static int lo_rw_aio(struct loop_device *lo, struct loop_cmd *cmd, /* nomerge for loop request queue */ WARN_ON(cmd->rq->bio != cmd->rq->biotail); + /* + * For multipage bvec support, it is safe to pass the bvec + * table to iov iterator, because iov iter still uses bvec + * iter helpers to travese bvec. + */ bvec = __bvec_iter_bvec(bio->bi_io_vec, bio->bi_iter); iov_iter_bvec(&iter, ITER_BVEC | rw, bvec, bio_segments(bio), blk_rq_bytes(cmd->rq)); -- 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