From patchwork Tue Dec 15 00:20:24 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pavel Begunkov X-Patchwork-Id: 11973429 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=-15.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 384DDC3526B for ; Tue, 15 Dec 2020 00:28:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 08B5F22258 for ; Tue, 15 Dec 2020 00:28:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729120AbgLOA1w (ORCPT ); Mon, 14 Dec 2020 19:27:52 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53504 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728450AbgLOAZI (ORCPT ); Mon, 14 Dec 2020 19:25:08 -0500 Received: from mail-wm1-x343.google.com (mail-wm1-x343.google.com [IPv6:2a00:1450:4864:20::343]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6B547C06138C; Mon, 14 Dec 2020 16:24:10 -0800 (PST) Received: by mail-wm1-x343.google.com with SMTP id k10so15342145wmi.3; Mon, 14 Dec 2020 16:24:10 -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 :mime-version:content-transfer-encoding; bh=v0AauUnwA0hTGdBXNj6ZzKlUOrb4jF47iEjWqFK5L8s=; b=DmTQasMwcOvVC2HGyReHTCHsrRm49zPi6M3MRtAMOhqhX/MN7tDKz9tL+2pg6+QqYB CXap+KpU5xs24Y+WYCf1WmIMcbkqlrNyus789gDHv7ZcPFhHbkPbeOMS/zQtebq3NWL0 g6sKVXm18j9BbKfBTXinHBaJ1rkacOcYlffL1aBWZLdVYiAedGshDJV8apYteChI1dp3 kwkWBENwuxx4wSeb6aRKG2sPyMMMglhBwVrK8hYRjGz+bUIbsu2XwQ7RGM4HF38LI006 yaGms8xc0u3XMms3xpgR52HhDX5ov0KL7K0BuvZS+UZXQZh49414R/7FwDK2hlXJMadg TuBw== 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:mime-version:content-transfer-encoding; bh=v0AauUnwA0hTGdBXNj6ZzKlUOrb4jF47iEjWqFK5L8s=; b=QyfMUBFuUm3Mfyzzb9fuP3ipEImcyr8tKELyi/+ZUCAPLuav8EL3G3tOKM6We2PZrY CDBzdgYzC9ahxAT08eTJvoIiwsvaUkBL+9cpE3J6H0OTXb9bK4d7ZC6UydHWeIH07MYH ieIy06LpjjGkc+9Uz5RsRbeoMUOIZwE4NXk87W6ONhfdcd2LyI5YyYzetneG8P59lxEF M/gHmyvOaKoo5Q6am/x0QUD6CSzlkusH1mIGRh/N4lGilN07WdrWGtMcSl0mV9jvdksi YfBU+SPPtRC+empqUcE2SSmUiFYFQCsuvcnoMihSj7tXGrC593wuEk0JOdJM9tjufmog vY7A== X-Gm-Message-State: AOAM532MMyZUprFztZ57rCLu6/Q7N6PwiBCyihtG8e/hb0mRPbzNL51n zTDXQVeQXJgEW2pqcu7AGBXRcE4THF/DkzlL X-Google-Smtp-Source: ABdhPJxINkanVy2QGQhY1u+YaY38qOJLZ6n+hZXE+kGwMf8ljRg3x4j8lZkvZFRa2g0tfnchLTq01Q== X-Received: by 2002:a1c:64c4:: with SMTP id y187mr25944685wmb.165.1607991848997; Mon, 14 Dec 2020 16:24:08 -0800 (PST) Received: from localhost.localdomain ([85.255.232.163]) by smtp.gmail.com with ESMTPSA id b19sm5362012wmj.37.2020.12.14.16.24.07 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 14 Dec 2020 16:24:08 -0800 (PST) From: Pavel Begunkov To: linux-block@vger.kernel.org Cc: Jens Axboe , Christoph Hellwig , Matthew Wilcox , Ming Lei , Johannes Weiner , Alexander Viro , "Darrick J . Wong" , "Martin K . Petersen" , Jonathan Corbet , linux-xfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, io-uring@vger.kernel.org, linux-kernel@vger.kernel.org, target-devel@vger.kernel.org, linux-scsi@vger.kernel.org, linux-doc@vger.kernel.org Subject: [PATCH v1 5/6] bio: add a helper calculating nr segments to alloc Date: Tue, 15 Dec 2020 00:20:24 +0000 Message-Id: <94b6f76d2d47569742ee47caede1504926f9807a.1607976425.git.asml.silence@gmail.com> X-Mailer: git-send-email 2.24.0 In-Reply-To: References: MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org A preparation patch. It adds a simple helper which abstracts out number of segments we're allocating for a bio from iov_iter_npages(). Signed-off-by: Pavel Begunkov Reviewed-by: Christoph Hellwig --- fs/block_dev.c | 7 ++++--- fs/iomap/direct-io.c | 9 ++++----- include/linux/bio.h | 6 ++++++ 3 files changed, 14 insertions(+), 8 deletions(-) diff --git a/fs/block_dev.c b/fs/block_dev.c index 9e56ee1f2652..1cbbc794edc6 100644 --- a/fs/block_dev.c +++ b/fs/block_dev.c @@ -417,7 +417,7 @@ __blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter, int nr_pages) dio->size += bio->bi_iter.bi_size; pos += bio->bi_iter.bi_size; - nr_pages = iov_iter_npages(iter, BIO_MAX_PAGES); + nr_pages = bio_iov_vecs_to_alloc(iter, BIO_MAX_PAGES); if (!nr_pages) { bool polled = false; @@ -482,9 +482,10 @@ blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter) { int nr_pages; - nr_pages = iov_iter_npages(iter, BIO_MAX_PAGES + 1); - if (!nr_pages) + if (!iov_iter_count(iter)) return 0; + + nr_pages = bio_iov_vecs_to_alloc(iter, BIO_MAX_PAGES + 1); if (is_sync_kiocb(iocb) && nr_pages <= BIO_MAX_PAGES) return __blkdev_direct_IO_simple(iocb, iter, nr_pages); diff --git a/fs/iomap/direct-io.c b/fs/iomap/direct-io.c index 933f234d5bec..ea1e8f696076 100644 --- a/fs/iomap/direct-io.c +++ b/fs/iomap/direct-io.c @@ -250,11 +250,8 @@ iomap_dio_bio_actor(struct inode *inode, loff_t pos, loff_t length, orig_count = iov_iter_count(dio->submit.iter); iov_iter_truncate(dio->submit.iter, length); - nr_pages = iov_iter_npages(dio->submit.iter, BIO_MAX_PAGES); - if (nr_pages <= 0) { - ret = nr_pages; + if (!iov_iter_count(dio->submit.iter)) goto out; - } if (need_zeroout) { /* zero out from the start of the block to the write offset */ @@ -263,6 +260,7 @@ iomap_dio_bio_actor(struct inode *inode, loff_t pos, loff_t length, iomap_dio_zero(dio, iomap, pos - pad, pad); } + nr_pages = bio_iov_vecs_to_alloc(dio->submit.iter, BIO_MAX_PAGES); do { size_t n; if (dio->error) { @@ -308,7 +306,8 @@ iomap_dio_bio_actor(struct inode *inode, loff_t pos, loff_t length, dio->size += n; copied += n; - nr_pages = iov_iter_npages(dio->submit.iter, BIO_MAX_PAGES); + nr_pages = bio_iov_vecs_to_alloc(dio->submit.iter, + BIO_MAX_PAGES); iomap_dio_submit_bio(dio, iomap, bio, pos); pos += n; } while (nr_pages); diff --git a/include/linux/bio.h b/include/linux/bio.h index 1edda614f7ce..2a9f3f0bbe0a 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -10,6 +10,7 @@ #include /* struct bio, bio_vec and BIO_* flags are defined in blk_types.h */ #include +#include #define BIO_DEBUG @@ -441,6 +442,11 @@ static inline void bio_wouldblock_error(struct bio *bio) bio_endio(bio); } +static inline int bio_iov_vecs_to_alloc(struct iov_iter *iter, int max_segs) +{ + return iov_iter_npages(iter, max_segs); +} + struct request_queue; extern int submit_bio_wait(struct bio *bio);