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=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,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 EFC98C282CA for ; Wed, 13 Feb 2019 01:55:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C69E2222C1 for ; Wed, 13 Feb 2019 01:55:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1733202AbfBMBzy (ORCPT ); Tue, 12 Feb 2019 20:55:54 -0500 Received: from mx1.redhat.com ([209.132.183.28]:43740 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728534AbfBMBzy (ORCPT ); Tue, 12 Feb 2019 20:55:54 -0500 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id E6F703DE0F; Wed, 13 Feb 2019 01:55:53 +0000 (UTC) Received: from firesoul.localdomain (ovpn-200-20.brq.redhat.com [10.40.200.20]) by smtp.corp.redhat.com (Postfix) with ESMTP id 1946862667; Wed, 13 Feb 2019 01:55:51 +0000 (UTC) Received: from [10.1.2.1] (localhost [IPv6:::1]) by firesoul.localdomain (Postfix) with ESMTP id 4336E306665E6; Wed, 13 Feb 2019 02:55:50 +0100 (CET) Subject: [net-next PATCH V3 3/3] page_pool: use DMA_ATTR_SKIP_CPU_SYNC for DMA mappings From: Jesper Dangaard Brouer To: netdev@vger.kernel.org, linux-mm@kvack.org Cc: Toke =?utf-8?q?H=C3=B8iland-J=C3=B8rgensen?= , Ilias Apalodimas , willy@infradead.org, Saeed Mahameed , Alexander Duyck , Jesper Dangaard Brouer , Andrew Morton , mgorman@techsingularity.net, "David S. Miller" , Tariq Toukan Date: Wed, 13 Feb 2019 02:55:50 +0100 Message-ID: <155002295022.5597.14139756432375272348.stgit@firesoul> In-Reply-To: <155002290134.5597.6544755780651689517.stgit@firesoul> References: <155002290134.5597.6544755780651689517.stgit@firesoul> User-Agent: StGit/0.17.1-dirty MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.29]); Wed, 13 Feb 2019 01:55:54 +0000 (UTC) Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org As pointed out by Alexander Duyck, the DMA mapping done in page_pool needs to use the DMA attribute DMA_ATTR_SKIP_CPU_SYNC. As the principle behind page_pool keeping the pages mapped is that the driver takes over the DMA-sync steps. Reported-by: Alexander Duyck Signed-off-by: Jesper Dangaard Brouer Signed-off-by: Ilias Apalodimas --- net/core/page_pool.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/net/core/page_pool.c b/net/core/page_pool.c index 897a69a1477e..5b2252c6d49b 100644 --- a/net/core/page_pool.c +++ b/net/core/page_pool.c @@ -141,9 +141,9 @@ static struct page *__page_pool_alloc_pages_slow(struct page_pool *pool, * into page private data (i.e 32bit cpu with 64bit DMA caps) * This mapping is kept for lifetime of page, until leaving pool. */ - dma = dma_map_page(pool->p.dev, page, 0, - (PAGE_SIZE << pool->p.order), - pool->p.dma_dir); + dma = dma_map_page_attrs(pool->p.dev, page, 0, + (PAGE_SIZE << pool->p.order), + pool->p.dma_dir, DMA_ATTR_SKIP_CPU_SYNC); if (dma_mapping_error(pool->p.dev, dma)) { put_page(page); return NULL; @@ -184,8 +184,9 @@ static void __page_pool_clean_page(struct page_pool *pool, dma = page->dma_addr; /* DMA unmap */ - dma_unmap_page(pool->p.dev, dma, - PAGE_SIZE << pool->p.order, pool->p.dma_dir); + dma_unmap_page_attrs(pool->p.dev, dma, + PAGE_SIZE << pool->p.order, pool->p.dma_dir, + DMA_ATTR_SKIP_CPU_SYNC); page->dma_addr = 0; }