Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932985Ab2EYU0X (ORCPT ); Fri, 25 May 2012 16:26:23 -0400 Received: from mail-pz0-f46.google.com ([209.85.210.46]:48893 "EHLO mail-pz0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757130Ab2EYU0N (ORCPT ); Fri, 25 May 2012 16:26:13 -0400 From: Kent Overstreet To: linux-kernel@vger.kernel.org, linux-bcache@vger.kernel.org, dm-devel@redhat.com, linux-fsdevel@vger.kernel.org Cc: Kent Overstreet , tj@kernel.org, axboe@kernel.dk, agk@redhat.com, neilb@suse.de, drbd-dev@lists.linbit.com, bharrosh@panasas.com, vgoyal@redhat.com, mpatocka@redhat.com, sage@newdream.net, yehuda@hq.newdream.net Subject: [PATCH v3 03/16] block: Add bio_reset() Date: Fri, 25 May 2012 13:25:26 -0700 Message-Id: <1337977539-16977-4-git-send-email-koverstreet@google.com> X-Mailer: git-send-email 1.7.9.3.327.g2980b In-Reply-To: <1337977539-16977-1-git-send-email-koverstreet@google.com> References: <1337977539-16977-1-git-send-email-koverstreet@google.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2406 Lines: 78 Reusing bios is something that's been highly frowned upon in the past, but driver code keeps doing it anyways. If it's going to happen anyways, we should provide a generic method. This'll help with getting rid of bi_destructor - drivers/block/pktcdvd.c was open coding it, by doing a bio_init() and resetting bi_destructor. Signed-off-by: Kent Overstreet Change-Id: Ib0a43dfcb3f6c22a54da513d4a86be544b5ffd95 --- fs/bio.c | 8 ++++++++ include/linux/bio.h | 1 + include/linux/blk_types.h | 6 ++++++ 3 files changed, 15 insertions(+) diff --git a/fs/bio.c b/fs/bio.c index 3667cef..240da21 100644 --- a/fs/bio.c +++ b/fs/bio.c @@ -259,6 +259,14 @@ void bio_init(struct bio *bio) } EXPORT_SYMBOL(bio_init); +void bio_reset(struct bio *bio) +{ + memset(bio, 0, BIO_RESET_BYTES); + bio->bi_flags = 1 << BIO_UPTODATE; + +} +EXPORT_SYMBOL(bio_reset); + /** * bio_alloc_bioset - allocate a bio for I/O * @gfp_mask: the GFP_ mask given to the slab allocator diff --git a/include/linux/bio.h b/include/linux/bio.h index 4d94eb8..e5c2504 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -226,6 +226,7 @@ extern void __bio_clone(struct bio *, struct bio *); extern struct bio *bio_clone(struct bio *, gfp_t); extern void bio_init(struct bio *); +extern void bio_reset(struct bio *); extern int bio_add_page(struct bio *, struct page *, unsigned int,unsigned int); extern int bio_add_pc_page(struct request_queue *, struct bio *, struct page *, diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h index dc0e399..6b7daf3 100644 --- a/include/linux/blk_types.h +++ b/include/linux/blk_types.h @@ -57,6 +57,10 @@ struct bio { unsigned int bi_seg_front_size; unsigned int bi_seg_back_size; + /* + * Everything starting with bi_max_vecs will be preserved by bio_reset() + */ + unsigned int bi_max_vecs; /* max bvl_vecs we can hold */ atomic_t bi_cnt; /* pin count */ @@ -83,6 +87,8 @@ struct bio { struct bio_vec bi_inline_vecs[0]; }; +#define BIO_RESET_BYTES offsetof(struct bio, bi_max_vecs) + /* * bio flags */ -- 1.7.9.3.327.g2980b -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/