From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756826AbYILOos (ORCPT ); Fri, 12 Sep 2008 10:44:48 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756514AbYILOog (ORCPT ); Fri, 12 Sep 2008 10:44:36 -0400 Received: from mx1.redhat.com ([66.187.233.31]:44901 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756693AbYILOof (ORCPT ); Fri, 12 Sep 2008 10:44:35 -0400 Date: Fri, 12 Sep 2008 10:45:23 -0400 (EDT) Message-Id: <20080912.104523.07457895.k-ueda@ct.jp.nec.com> To: jens.axboe@oracle.com, agk@redhat.com, James.Bottomley@HansenPartnership.com Cc: linux-kernel@vger.kernel.org, linux-scsi@vger.kernel.org, dm-devel@redhat.com, j-nomura@ce.jp.nec.com, k-ueda@ct.jp.nec.com Subject: [PATCH 08/13] dm: add kmem_cache for request-based dm From: Kiyoshi Ueda In-Reply-To: <20080912.103814.74754581.k-ueda@ct.jp.nec.com> References: <20080912.103814.74754581.k-ueda@ct.jp.nec.com> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This patch prepares some kmem_cache for request-based dm. Signed-off-by: Kiyoshi Ueda Signed-off-by: Jun'ichi Nomura Cc: Alasdair G Kergon --- drivers/md/dm.c | 45 ++++++++++++++++++++++++++++++++++++++++++++- 1 files changed, 44 insertions(+), 1 deletion(-) Index: 2.6.27-rc6/drivers/md/dm.c =================================================================== --- 2.6.27-rc6.orig/drivers/md/dm.c +++ 2.6.27-rc6/drivers/md/dm.c @@ -32,6 +32,7 @@ static unsigned int _major = 0; static DEFINE_SPINLOCK(_minor_lock); /* + * For bio based dm. * One of these is allocated per bio. */ struct dm_io { @@ -43,6 +44,7 @@ struct dm_io { }; /* + * For bio based dm. * One of these is allocated per target within a bio. Hopefully * this will be simplified out one day. */ @@ -52,6 +54,31 @@ struct dm_target_io { union map_info info; }; +/* + * For request based dm. + * One of these is allocated per request. + * + * Since assuming "original request : cloned request = 1 : 1" and + * a counter for number of clones like struct dm_io.io_count isn't needed, + * struct dm_io and struct target_io can be merged. + */ +struct dm_rq_target_io { + struct mapped_device *md; + struct dm_target *ti; + struct request *orig, clone; + int error; + union map_info info; +}; + +/* + * For request based dm. + * One of these is allocated per bio. + */ +struct dm_clone_bio_info { + struct bio *orig; + struct request *rq; +}; + union map_info *dm_get_mapinfo(struct bio *bio) { if (bio && bio->bi_private) @@ -147,6 +174,8 @@ struct mapped_device { #define MIN_IOS 256 static struct kmem_cache *_io_cache; static struct kmem_cache *_tio_cache; +static struct kmem_cache *_rq_tio_cache; +static struct kmem_cache *_bio_info_cache; static int __init local_init(void) { @@ -162,9 +191,17 @@ static int __init local_init(void) if (!_tio_cache) goto out_free_io_cache; + _rq_tio_cache = KMEM_CACHE(dm_rq_target_io, 0); + if (!_rq_tio_cache) + goto out_free_tio_cache; + + _bio_info_cache = KMEM_CACHE(dm_clone_bio_info, 0); + if (!_bio_info_cache) + goto out_free_rq_tio_cache; + r = dm_uevent_init(); if (r) - goto out_free_tio_cache; + goto out_free_bio_info_cache; _major = major; r = register_blkdev(_major, _name); @@ -178,6 +215,10 @@ static int __init local_init(void) out_uevent_exit: dm_uevent_exit(); +out_free_bio_info_cache: + kmem_cache_destroy(_bio_info_cache); +out_free_rq_tio_cache: + kmem_cache_destroy(_rq_tio_cache); out_free_tio_cache: kmem_cache_destroy(_tio_cache); out_free_io_cache: @@ -188,6 +229,8 @@ out_free_io_cache: static void local_exit(void) { + kmem_cache_destroy(_bio_info_cache); + kmem_cache_destroy(_rq_tio_cache); kmem_cache_destroy(_tio_cache); kmem_cache_destroy(_io_cache); unregister_blkdev(_major, _name);