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=-15.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 082BEC433B4 for ; Fri, 30 Apr 2021 05:55:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E222E61462 for ; Fri, 30 Apr 2021 05:55:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230280AbhD3F4M (ORCPT ); Fri, 30 Apr 2021 01:56:12 -0400 Received: from mail.kernel.org ([198.145.29.99]:48274 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230202AbhD3F4M (ORCPT ); Fri, 30 Apr 2021 01:56:12 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 5E4B261466; Fri, 30 Apr 2021 05:55:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1619762124; bh=kpzNCcG57QovQCy/AaKA3fwXd9iKuvPrR2ThqJUwguI=; h=Date:From:To:Subject:In-Reply-To:From; b=ZuDgq9ML9pXGt/nYbZtiC9ztHrRChGwZCh2GBl2rwsvX0t3mjPisHc+m5e9Ogl45y gcE7plCfTwiWFRk9Kt3VrWaLkuBBuf8Ct/CwpAuoGym5us821+WW1LUZMMHzYnagTm NdFqh54nYgq8fHPyL4wk39iBXXQGTCDVX8slc4qI= Date: Thu, 29 Apr 2021 22:55:24 -0700 From: Andrew Morton To: akpm@linux-foundation.org, axboe@kernel.dk, jack@suse.cz, linux-mm@kvack.org, mm-commits@vger.kernel.org, torvalds@linux-foundation.org, willy@infradead.org Subject: [patch 043/178] iomap: use filemap_range_needs_writeback() for O_DIRECT reads Message-ID: <20210430055524.Z5Df0yuXI%akpm@linux-foundation.org> In-Reply-To: <20210429225251.02b6386d21b69255b4f6c163@linux-foundation.org> User-Agent: s-nail v14.8.16 Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org From: Jens Axboe Subject: iomap: use filemap_range_needs_writeback() for O_DIRECT reads For reads, use the better variant of checking for the need to call filemap_write_and_wait_range() when doing O_DIRECT. This avoids falling back to the slow path for IOCB_NOWAIT, if there are no pages to wait for (or write out). Link: https://lkml.kernel.org/r/20210224164455.1096727-4-axboe@kernel.dk Signed-off-by: Jens Axboe Reviewed-by: Jan Kara Cc: Matthew Wilcox (Oracle) Signed-off-by: Andrew Morton --- fs/iomap/direct-io.c | 24 ++++++++++++++++-------- 1 file changed, 16 insertions(+), 8 deletions(-) --- a/fs/iomap/direct-io.c~iomap-use-filemap_range_needs_writeback-for-o_direct-reads +++ a/fs/iomap/direct-io.c @@ -487,12 +487,28 @@ __iomap_dio_rw(struct kiocb *iocb, struc if (pos >= dio->i_size) goto out_free_dio; + if (iocb->ki_flags & IOCB_NOWAIT) { + if (filemap_range_needs_writeback(mapping, pos, end)) { + ret = -EAGAIN; + goto out_free_dio; + } + iomap_flags |= IOMAP_NOWAIT; + } + if (iter_is_iovec(iter)) dio->flags |= IOMAP_DIO_DIRTY; } else { iomap_flags |= IOMAP_WRITE; dio->flags |= IOMAP_DIO_WRITE; + if (iocb->ki_flags & IOCB_NOWAIT) { + if (filemap_range_has_page(mapping, pos, end)) { + ret = -EAGAIN; + goto out_free_dio; + } + iomap_flags |= IOMAP_NOWAIT; + } + /* for data sync or sync, we need sync completion processing */ if (iocb->ki_flags & IOCB_DSYNC) dio->flags |= IOMAP_DIO_NEED_SYNC; @@ -507,14 +523,6 @@ __iomap_dio_rw(struct kiocb *iocb, struc dio->flags |= IOMAP_DIO_WRITE_FUA; } - if (iocb->ki_flags & IOCB_NOWAIT) { - if (filemap_range_has_page(mapping, pos, end)) { - ret = -EAGAIN; - goto out_free_dio; - } - iomap_flags |= IOMAP_NOWAIT; - } - if (dio_flags & IOMAP_DIO_OVERWRITE_ONLY) { ret = -EAGAIN; if (pos >= dio->i_size || pos + count > dio->i_size) _