From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f194.google.com ([209.85.192.194]:34853 "EHLO mail-pf0-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S941917AbcJ2INm (ORCPT ); Sat, 29 Oct 2016 04:13:42 -0400 From: Ming Lei To: Jens Axboe , linux-kernel@vger.kernel.org Cc: linux-block@vger.kernel.org, linux-fsdevel@vger.kernel.org, Christoph Hellwig , "Kirill A . Shutemov" , Ming Lei , Mike Christie , Hannes Reinecke , Dan Williams , Toshi Kani Subject: [PATCH 23/60] block: introduce flag QUEUE_FLAG_NO_MP Date: Sat, 29 Oct 2016 16:08:22 +0800 Message-Id: <1477728600-12938-24-git-send-email-tom.leiming@gmail.com> In-Reply-To: <1477728600-12938-1-git-send-email-tom.leiming@gmail.com> References: <1477728600-12938-1-git-send-email-tom.leiming@gmail.com> Sender: linux-block-owner@vger.kernel.org List-Id: linux-block@vger.kernel.org MD(especially raid1 and raid10) is a bit difficult to support multipage bvec, so introduce this flag for not enabling multipage bvec, then MD can still accept singlepage bvec only, and once direct access to bvec table in MD and other fs/drivers are cleanuped, the flag can be removed. BTRFS has the similar issue too. Signed-off-by: Ming Lei --- include/linux/blkdev.h | 2 ++ 1 file changed, 2 insertions(+) diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index c47c358ba052..e4dd25361bd6 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -505,6 +505,7 @@ struct request_queue { #define QUEUE_FLAG_FUA 24 /* device supports FUA writes */ #define QUEUE_FLAG_FLUSH_NQ 25 /* flush not queueuable */ #define QUEUE_FLAG_DAX 26 /* device supports DAX */ +#define QUEUE_FLAG_NO_MP 27 /* multipage bvecs isn't ready */ #define QUEUE_FLAG_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \ (1 << QUEUE_FLAG_STACKABLE) | \ @@ -595,6 +596,7 @@ static inline void queue_flag_clear(unsigned int flag, struct request_queue *q) #define blk_queue_secure_erase(q) \ (test_bit(QUEUE_FLAG_SECERASE, &(q)->queue_flags)) #define blk_queue_dax(q) test_bit(QUEUE_FLAG_DAX, &(q)->queue_flags) +#define blk_queue_no_mp(q) test_bit(QUEUE_FLAG_NO_MP, &(q)->queue_flags) #define blk_noretry_request(rq) \ ((rq)->cmd_flags & (REQ_FAILFAST_DEV|REQ_FAILFAST_TRANSPORT| \ -- 2.7.4