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=-13.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,UNWANTED_LANGUAGE_BODY, URIBL_BLOCKED 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 825ABC4338F for ; Thu, 5 Aug 2021 17:31:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5899B610A2 for ; Thu, 5 Aug 2021 17:31:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230385AbhHERbT (ORCPT ); Thu, 5 Aug 2021 13:31:19 -0400 Received: from mail.kernel.org ([198.145.29.99]:55558 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230004AbhHERbT (ORCPT ); Thu, 5 Aug 2021 13:31:19 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 0098460F42; Thu, 5 Aug 2021 17:31:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1628184665; bh=MoFgSn3KWSScKi/BuebgAcN0GTgylIPN8NwZe4LfwiI=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=Gt/rRgIF0YR8b8yYG8cXDUIv7FCCUeplyvwl/9lmRBOKuuw9Uo8ks5g+UQS/JIWos 9PqN8R8mHP/E15SDN03bac3Tz3czxBa71QupTjZL54gm1QNtUc2EPu43oF4wkR3oKu q+8WgXSCLMAxTY2UFBFQTr3Rq8wI2QvOGSFNqIOQ5ACKdU9uH0ziPNC0L/66Xl02dx eydwuMV1XvVGCCS9PgXp+MhgC2NkVuwgs5Gfnzt8J53OLEN8w4wEUZBVf0gbHn43vJ ArCx/7ZhuVg+0yRAve7VRU2zdAUlXO25qYrkXHHw0D8VjMYoaPpkx2MjPxp325liXg 4gXpPXsyXLXCA== Date: Thu, 5 Aug 2021 10:31:04 -0700 From: "Darrick J. Wong" To: "Matthew Wilcox (Oracle)" Cc: linux-xfs@vger.kernel.org, linux-fsdevel@vger.kernel.org Subject: Re: [PATCH 1/2] iomap: Use kmap_local_page instead of kmap_atomic Message-ID: <20210805173104.GF3601405@magnolia> References: <20210803193134.1198733-1-willy@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210803193134.1198733-1-willy@infradead.org> Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org On Tue, Aug 03, 2021 at 08:31:33PM +0100, Matthew Wilcox (Oracle) wrote: > kmap_atomic() has the side-effect of disabling pagefaults and > preemption. kmap_local_page() does not do this and is preferred. > > Signed-off-by: Matthew Wilcox (Oracle) Pretty straightforward. Reviewed-by: Darrick J. Wong --D > --- > fs/iomap/buffered-io.c | 10 +++++----- > 1 file changed, 5 insertions(+), 5 deletions(-) > > diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c > index c1c8cd41ea81..8ee0211bea86 100644 > --- a/fs/iomap/buffered-io.c > +++ b/fs/iomap/buffered-io.c > @@ -223,10 +223,10 @@ static int iomap_read_inline_data(struct inode *inode, struct page *page, > if (poff > 0) > iomap_page_create(inode, page); > > - addr = kmap_atomic(page) + poff; > + addr = kmap_local_page(page) + poff; > memcpy(addr, iomap->inline_data, size); > memset(addr + size, 0, PAGE_SIZE - poff - size); > - kunmap_atomic(addr); > + kunmap_local(addr); > iomap_set_range_uptodate(page, poff, PAGE_SIZE - poff); > return PAGE_SIZE - poff; > } > @@ -682,9 +682,9 @@ static size_t iomap_write_end_inline(struct inode *inode, struct page *page, > BUG_ON(!iomap_inline_data_valid(iomap)); > > flush_dcache_page(page); > - addr = kmap_atomic(page); > - memcpy(iomap_inline_data(iomap, pos), addr + pos, copied); > - kunmap_atomic(addr); > + addr = kmap_local_page(page) + pos; > + memcpy(iomap_inline_data(iomap, pos), addr, copied); > + kunmap_local(addr); > > mark_inode_dirty(inode); > return copied; > -- > 2.30.2 >