From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754116Ab2ITDTn (ORCPT ); Wed, 19 Sep 2012 23:19:43 -0400 Received: from mail-pb0-f46.google.com ([209.85.160.46]:53021 "EHLO mail-pb0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754074Ab2ITDS6 (ORCPT ); Wed, 19 Sep 2012 23:18:58 -0400 From: Robin Dong To: linux-kernel@vger.kernel.org, dm-devel@redhat.com Cc: Robin Dong Subject: [PATCH 2/2] md: modify dm_io() so it could return bios instead of submitting it Date: Thu, 20 Sep 2012 11:18:42 +0800 Message-Id: <1348111122-27400-2-git-send-email-robin.k.dong@gmail.com> X-Mailer: git-send-email 1.7.3.2 In-Reply-To: <1348111122-27400-1-git-send-email-robin.k.dong@gmail.com> References: <1348111122-27400-1-git-send-email-robin.k.dong@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Robin Dong When trying to modify flashcache to request based (current it's bio based), we need to make request from bios by ourselves, but dm_io() will submit these bios directly, so we propose to modify the dm_io() to return bios instead of submiting it. This could also improve the flexibility of dm_io(). Signed-off-by: Robin Dong --- drivers/md/dm.c | 11 +++++++++++ include/linux/device-mapper.h | 3 +++ 2 files changed, 14 insertions(+), 0 deletions(-) diff --git a/drivers/md/dm.c b/drivers/md/dm.c index 4e09b6f..bf6e3bb 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -1459,11 +1459,22 @@ static int dm_request_based(struct mapped_device *md) static void dm_request(struct request_queue *q, struct bio *bio) { struct mapped_device *md = q->queuedata; + struct dm_table *map = dm_get_live_table(md); + struct dm_target *ti = dm_table_find_target(map, bio->bi_sector); + + if (ti->type->mk_rq) { + ti->type->mk_rq(ti, q, bio); + goto out; + } if (dm_request_based(md)) blk_queue_bio(q, bio); else _dm_request(q, bio); + +out: + dm_table_put(map); + return; } void dm_dispatch_request(struct request *rq) diff --git a/include/linux/device-mapper.h b/include/linux/device-mapper.h index 38d27a1..2386389 100644 --- a/include/linux/device-mapper.h +++ b/include/linux/device-mapper.h @@ -50,6 +50,8 @@ typedef int (*dm_map_fn) (struct dm_target *ti, struct bio *bio, union map_info *map_context); typedef int (*dm_map_request_fn) (struct dm_target *ti, struct request *clone, union map_info *map_context); +typedef int (*dm_make_request_fn) (struct dm_target *ti, + struct request_queue *q, struct bio *bio); /* * Returns: @@ -136,6 +138,7 @@ struct target_type { dm_dtr_fn dtr; dm_map_fn map; dm_map_request_fn map_rq; + dm_make_request_fn mk_rq; dm_endio_fn end_io; dm_request_endio_fn rq_end_io; dm_presuspend_fn presuspend; -- 1.7.1