Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752681AbdFZMQb (ORCPT ); Mon, 26 Jun 2017 08:16:31 -0400 Received: from mx1.redhat.com ([209.132.183.28]:51724 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752005AbdFZMQ2 (ORCPT ); Mon, 26 Jun 2017 08:16:28 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 2350980465 Authentication-Results: ext-mx04.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx04.extmail.prod.ext.phx2.redhat.com; spf=pass smtp.mailfrom=ming.lei@redhat.com DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.redhat.com 2350980465 From: Ming Lei To: Jens Axboe , Christoph Hellwig , Huang Ying , Andrew Morton , Alexander Viro Cc: linux-kernel@vger.kernel.org, linux-block@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, Ming Lei Subject: [PATCH v2 21/51] block: implement sp version of bvec iterator helpers Date: Mon, 26 Jun 2017 20:10:04 +0800 Message-Id: <20170626121034.3051-22-ming.lei@redhat.com> In-Reply-To: <20170626121034.3051-1-ming.lei@redhat.com> References: <20170626121034.3051-1-ming.lei@redhat.com> X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.28]); Mon, 26 Jun 2017 12:16:18 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1837 Lines: 57 This patch implements singlepage version of the following 3 helpers: - bvec_iter_offset_sp() - bvec_iter_len_sp() - bvec_iter_page_sp() So that one multipage bvec can be splited to singlepage bvec, and make users of current bvec iterator happy. Signed-off-by: Ming Lei --- include/linux/bvec.h | 18 +++++++++++++++--- 1 file changed, 15 insertions(+), 3 deletions(-) diff --git a/include/linux/bvec.h b/include/linux/bvec.h index f52587e283d4..61632e9db3b8 100644 --- a/include/linux/bvec.h +++ b/include/linux/bvec.h @@ -22,6 +22,7 @@ #include #include +#include /* * What is multipage bvecs(segment)? @@ -95,14 +96,25 @@ struct bvec_iter { #define bvec_iter_offset_mp(bvec, iter) \ (__bvec_iter_bvec((bvec), (iter))->bv_offset + (iter).bi_bvec_done) +#define bvec_iter_page_idx_mp(bvec, iter) \ + (bvec_iter_offset_mp((bvec), (iter)) / PAGE_SIZE) + + /* * of singlepage(sp) segment. * * This helpers will be implemented for building sp bvec in flight. */ -#define bvec_iter_offset_sp(bvec, iter) bvec_iter_offset_mp((bvec), (iter)) -#define bvec_iter_len_sp(bvec, iter) bvec_iter_len_mp((bvec), (iter)) -#define bvec_iter_page_sp(bvec, iter) bvec_iter_page_mp((bvec), (iter)) +#define bvec_iter_offset_sp(bvec, iter) \ + (bvec_iter_offset_mp((bvec), (iter)) % PAGE_SIZE) + +#define bvec_iter_len_sp(bvec, iter) \ + min_t(unsigned, bvec_iter_len_mp((bvec), (iter)), \ + (PAGE_SIZE - (bvec_iter_offset_sp((bvec), (iter))))) + +#define bvec_iter_page_sp(bvec, iter) \ + nth_page(bvec_iter_page_mp((bvec), (iter)), \ + bvec_iter_page_idx_mp((bvec), (iter))) /* current interfaces support sp style at default */ #define bvec_iter_page(bvec, iter) bvec_iter_page_sp((bvec), (iter)) -- 2.9.4