From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 56126C43381 for ; Thu, 21 Mar 2019 12:30:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2ED87218D8 for ; Thu, 21 Mar 2019 12:30:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727959AbfCUMaw (ORCPT ); Thu, 21 Mar 2019 08:30:52 -0400 Received: from mx2.suse.de ([195.135.220.15]:50212 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727874AbfCUMaw (ORCPT ); Thu, 21 Mar 2019 08:30:52 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id E3E0AACD4; Thu, 21 Mar 2019 12:30:50 +0000 (UTC) From: Johannes Thumshirn To: Jens Axboe Cc: Hannes Reinecke , Bart Van Assche , Christoph Hellwig , Jan Kara , Linux Block Layer Mailinglist , Linux FSDEVEL Mailinglist , Johannes Thumshirn Subject: [PATCH 1/2] block: bio: ensure newly added bio flags don't override BVEC_POOL_IDX Date: Thu, 21 Mar 2019 13:30:44 +0100 Message-Id: <20190321123045.32396-2-jthumshirn@suse.de> X-Mailer: git-send-email 2.16.4 In-Reply-To: <20190321123045.32396-1-jthumshirn@suse.de> References: <20190321123045.32396-1-jthumshirn@suse.de> Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org With the introduction of BIO_ALLOCED we've used up all available bits in bio::bi_flags. Make sure no-one adds a new one and thus overrides the BVEC_POOL_IDX Signed-off-by: Johannes Thumshirn --- block/bio.c | 8 ++++++++ include/linux/blk_types.h | 31 +++++++++++++++++-------------- 2 files changed, 25 insertions(+), 14 deletions(-) diff --git a/block/bio.c b/block/bio.c index 4db1008309ed..8c689aed46a0 100644 --- a/block/bio.c +++ b/block/bio.c @@ -2126,12 +2126,20 @@ static void __init biovec_init_slabs(void) } } +static inline void bio_flag_buildtime_check(void) +{ + BUILD_BUG_ON(BIO_FLAG_LAST > BVEC_POOL_OFFSET); +} + static int __init init_bio(void) { bio_slab_max = 2; bio_slab_nr = 0; bio_slabs = kcalloc(bio_slab_max, sizeof(struct bio_slab), GFP_KERNEL); + + bio_flag_buildtime_check(); + if (!bio_slabs) panic("bio: can't allocate bios\n"); diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h index d66bf5f32610..0273bad71a96 100644 --- a/include/linux/blk_types.h +++ b/include/linux/blk_types.h @@ -215,20 +215,23 @@ struct bio { /* * bio flags */ -#define BIO_SEG_VALID 1 /* bi_phys_segments valid */ -#define BIO_CLONED 2 /* doesn't own data */ -#define BIO_BOUNCED 3 /* bio is a bounce bio */ -#define BIO_USER_MAPPED 4 /* contains user pages */ -#define BIO_NULL_MAPPED 5 /* contains invalid user pages */ -#define BIO_QUIET 6 /* Make BIO Quiet */ -#define BIO_CHAIN 7 /* chained bio, ->bi_remaining in effect */ -#define BIO_REFFED 8 /* bio has elevated ->bi_cnt */ -#define BIO_THROTTLED 9 /* This bio has already been subjected to - * throttling rules. Don't do it again. */ -#define BIO_TRACE_COMPLETION 10 /* bio_endio() should trace the final completion - * of this bio. */ -#define BIO_QUEUE_ENTERED 11 /* can use blk_queue_enter_live() */ -#define BIO_TRACKED 12 /* set if bio goes through the rq_qos path */ +enum { + BIO_SEG_VALID = 1, /* bi_phys_segments valid */ + BIO_CLONED = 2, /* doesn't own data */ + BIO_BOUNCED = 3, /* bio is a bounce bio */ + BIO_USER_MAPPED = 4, /* contains user pages */ + BIO_NULL_MAPPED = 5, /* contains invalid user pages */ + BIO_QUIET = 6, /* Make BIO Quiet */ + BIO_CHAIN = 7, /* chained bio, ->bi_remaining in effect */ + BIO_REFFED = 8, /* bio has elevated ->bi_cnt */ + BIO_THROTTLED = 9, /* This bio has already been subjected to + * throttling rules. Don't do it again. */ + BIO_TRACE_COMPLETION = 10, /* bio_endio() should trace the final completion + * of this bio. */ + BIO_QUEUE_ENTERED = 11, /* can use blk_queue_enter_live() */ + BIO_TRACKED = 12, /* set if bio goes through the rq_qos path */ + BIO_FLAG_LAST +}; /* See BVEC_POOL_OFFSET below before adding new flags */ -- 2.16.4