From patchwork Tue Dec 27 15:56:19 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ming Lei X-Patchwork-Id: 9489549 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 93FF6601D2 for ; Tue, 27 Dec 2016 16:10:17 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 81CD0200E7 for ; Tue, 27 Dec 2016 16:10:17 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 74C9D25E13; Tue, 27 Dec 2016 16:10:17 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.3 required=2.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED, DKIM_SIGNED, FREEMAIL_FROM, RCVD_IN_DNSWL_HI, RCVD_IN_SORBS_SPAM, T_DKIM_INVALID autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id E975E200E7 for ; Tue, 27 Dec 2016 16:10:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933240AbcL0QJx (ORCPT ); Tue, 27 Dec 2016 11:09:53 -0500 Received: from mail-pg0-f68.google.com ([74.125.83.68]:34638 "EHLO mail-pg0-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933116AbcL0QJp (ORCPT ); Tue, 27 Dec 2016 11:09:45 -0500 Received: by mail-pg0-f68.google.com with SMTP id b1so12814460pgc.1; Tue, 27 Dec 2016 08:09:44 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=weID8XJ4r5DavQFEouu8nQnXaOtzenoavCwnvwGv9UQ=; b=JHLOUDo1PzFN9aAjW13DJaYOUfmDVpiajOBVqQ7Ymj7qHUsRicQrTNzgNwB5uhOD6y 3iuie8fmZelAbEhyJGvOe5SC7SuvDEEyII7cEpsgSTqb1tHDLMtOaZKALF2OZQxmqSRF IhOEy8y+FnHtw9tyN99PSi8sMz3j8xvJ6oKDyI0EAMYFByKS9GhUVlT8LMHg9s+IydhP G8/45MGptGsc2VnrG7xBfeqwEp+qmOds5RCHSV+hmn56haOnOn6Zgqh6P3AvL0CqOLkf sjdM2/r1JYAx0hzHx2dQoy95u3YHmS3BWLqSkm2WH/vqUM2px5MvLfkuHbvoY1vzifs1 S+bg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=weID8XJ4r5DavQFEouu8nQnXaOtzenoavCwnvwGv9UQ=; b=uB3X9UYoIaDWyWZjkx0cwkcAzfz91O1j42W5SzQmRhlsMKqazOA2t4KUNULnrSpZvV NWUKoIFlYJ31ER9G7hERS30vb+Lv9+mObSwkGL2Hw/mtgJ8SkqmxK57uKFllTX51ebsb NnrM6iSbIHmvzeRBH10xbXY9UHJh3j0TIb6uAefxtBJJQL/aiBDg+xLX7oK9/d69thpZ qMlPiIL9hNbbTzk+hjAZDSWthJfAfXzlmaNPa2zYcJKC2eS2wwSwv3zBGctxM1hiwo+S m72RO6Y/Nb/3lad+4a66Gt+eE2gb1rSP+E/N1Fg585KADKHUjvnCuQcc7j62OyqgL6lP /M8w== X-Gm-Message-State: AIkVDXItqo52Ksu4t6a4etJ4rhKbpWhiU5t7+suh2zshiQKIEGwChhsirltV7X9uRR08LQ== X-Received: by 10.84.210.233 with SMTP id a96mr67348895pli.72.1482854515399; Tue, 27 Dec 2016 08:01:55 -0800 (PST) Received: from localhost ([45.35.47.137]) by smtp.gmail.com with ESMTPSA id p13sm91334015pgf.47.2016.12.27.08.01.53 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 27 Dec 2016 08:01:54 -0800 (PST) From: Ming Lei To: Jens Axboe , linux-kernel@vger.kernel.org Cc: linux-block@vger.kernel.org, Christoph Hellwig , Ming Lei , Mike Christie , Hannes Reinecke , Kent Overstreet , Chaitanya Kulkarni , Shaun Tancheff , Johannes Thumshirn , Bart Van Assche Subject: [PATCH v1 30/54] block: bio: introduce single/multi page version of bio_for_each_segment_all() Date: Tue, 27 Dec 2016 23:56:19 +0800 Message-Id: <1482854250-13481-31-git-send-email-tom.leiming@gmail.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1482854250-13481-1-git-send-email-tom.leiming@gmail.com> References: <1482854250-13481-1-git-send-email-tom.leiming@gmail.com> Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP This patches introduce bio_for_each_segment_all_sp() and bio_for_each_segment_all_mp(). bio_for_each_segment_all_sp() is for replacing bio_for_each_segment_all() in case that the returned bvec has to be single page bvec. bio_for_each_segment_all_mp() is for replacing bio_for_each_segment_all() in case that user wants to update the returned bvec via the pointer. Signed-off-by: Ming Lei --- include/linux/bio.h | 24 ++++++++++++++++++++++++ include/linux/blk_types.h | 6 ++++++ 2 files changed, 30 insertions(+) diff --git a/include/linux/bio.h b/include/linux/bio.h index 79079bc5a1be..efa0b3627735 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -217,6 +217,30 @@ static inline void bio_advance_iter_mp(struct bio *bio, struct bvec_iter *iter, #define bio_for_each_segment_mp(bvl, bio, iter) \ __bio_for_each_segment_mp(bvl, bio, iter, (bio)->bi_iter) +/* + * This helper returns each bvec stored in bvec table directly, + * so the returned bvec points to one multipage bvec in the table + * and caller can update the bvec via the returnd pointer. + */ +#define bio_for_each_segment_all_mp(bvl, bio, i) \ + bio_for_each_segment_all((bvl), (bio), (i)) + +/* + * This helper returns singlepage bvec to caller, and the sp bvec + * is generated in-flight from multipage bvec stored in bvec table. + * So we can _not_ change the bvec stored in bio->bi_io_vec[] via + * this helper. + * + * If someone need to update bvec in the table, please use + * bio_for_each_segment_all_mp() and make sure it is correctly used + * since the bvec points to one multipage bvec. + */ +#define bio_for_each_segment_all_sp(bvl, bio, i, bi) \ + for ((bi).iter = BVEC_ITER_ALL_INIT, i = 0, bvl = &(bi).bv; \ + (bi).iter.bi_idx < (bio)->bi_vcnt && \ + (((bi).bv = bio_iter_iovec((bio), (bi).iter)), 1); \ + bio_advance_iter((bio), &(bi).iter, (bi).bv.bv_len), i++) + #define bio_iter_last(bvec, iter) ((iter).bi_size == (bvec).bv_len) static inline unsigned __bio_segments(struct bio *bio, bool mp) diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h index 519ea2c9df61..ef8e30abb099 100644 --- a/include/linux/blk_types.h +++ b/include/linux/blk_types.h @@ -89,6 +89,12 @@ struct bio { #define BIO_RESET_BYTES offsetof(struct bio, bi_max_vecs) +/* this iter is only for implementing bio_for_each_segment_rd() */ +struct bvec_iter_all { + struct bvec_iter iter; + struct bio_vec bv; /* in-flight singlepage bvec */ +}; + /* * bio flags */