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=-6.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, 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 404D9C2D0E5 for ; Wed, 25 Mar 2020 19:16:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 15569206F6 for ; Wed, 25 Mar 2020 19:16:57 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linux-powerpc-org.20150623.gappssmtp.com header.i=@linux-powerpc-org.20150623.gappssmtp.com header.b="iv52F78z" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727763AbgCYTQ4 (ORCPT ); Wed, 25 Mar 2020 15:16:56 -0400 Received: from mail-vk1-f194.google.com ([209.85.221.194]:41741 "EHLO mail-vk1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727281AbgCYTQz (ORCPT ); Wed, 25 Mar 2020 15:16:55 -0400 Received: by mail-vk1-f194.google.com with SMTP id q8so1006052vka.8 for ; Wed, 25 Mar 2020 12:16:53 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-powerpc-org.20150623.gappssmtp.com; s=20150623; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc; bh=hVPS6ck2mwW3cLkOAy6o7QeijQEfZpDs1fTPD3JBZ1E=; b=iv52F78zk6Vs7RGp7ez9RlX7p1wE2SGhM4jg/CTDQ+mjK+g7XvA9pKAnkS9TwRLPdQ WOxj+TkkfI1b7MoFq36v5/Wpw3cJ4zV/Sj45p6zhRgqY+f0uqU+5jfZfv4BWzi4qxb0O tZbziPa8VfqLJOIdF7tMYbgzIBjv8ihQI8rv8lo2RrascUvwGHMR8kjaE6VOQfE3GtHz Qc+J9JtDRe8MKKevF7aujzYHcpEZubrkHRQzaZAmEpP17Rlxwe3dy76y3vHl4qsjggOm MAJYNoV+Ou17rzxFEx8xxODOlcgSDwd1S2nuxpouG2uEYdYK/Zc/ta/3y1Y45oj1tkuO hLMw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:to:cc; bh=hVPS6ck2mwW3cLkOAy6o7QeijQEfZpDs1fTPD3JBZ1E=; b=AaRAuSW8n99aV+x6+gXSLsoSYvy0BajI8SO1DYQNkXoFI8E2pwZhK6OAMziYUiVr0f ltEVTucx1CV6uyUpSM/csPvoRPvp8xEFDtWIyJ8P18MP9D9hrNXgENUHLTf9SyaPtxoC qRbOGylMQaaGhfZNdv7mLKXK4nldGNwEoAdY1u5NMRYfimSbFxvD5XIDPYtng+xwOF2n d0FAhdbw1k/SlFKOnadErC+aL8pF4S+/E4E7ra3ntNl7llB6ypSLfZLDCQxnOJXZ7qYN PG8Rkcb82LlKNl9skqoQXk8/jaa9nG5sBgJeZrzqJZ63xRdnfNoPCYGA8n4cYtr/+jUh 1ZgQ== X-Gm-Message-State: ANhLgQ0+sNnmJ7lFYzpzioNaCAVUFZV/2xM/rsBus1nR+p05cc+9/1DM Qq1P5jXf0Te6VjnmRKwQJ6UrDmGn4SehV22ijpdvoAbl X-Google-Smtp-Source: ADFU+vvDzI94z6h5mDZqGcVLDi9Rfw4yyovMqFzyevqLbjHesmI4sHR3ZRzWxYoiiqQZbG+7UEVyPV0j2BKbk8LrPPo= X-Received: by 2002:ac5:cd83:: with SMTP id i3mr3757164vka.58.1585163813073; Wed, 25 Mar 2020 12:16:53 -0700 (PDT) MIME-Version: 1.0 Received: by 2002:a9f:3b21:0:0:0:0:0 with HTTP; Wed, 25 Mar 2020 12:16:52 -0700 (PDT) X-Originating-IP: [5.35.40.234] In-Reply-To: <20200325160211.1b887ca5@carbon> References: <1585145575-14477-1-git-send-email-kda@linux-powerpc.org> <20200325160211.1b887ca5@carbon> From: Denis Kirjanov Date: Wed, 25 Mar 2020 22:16:52 +0300 Message-ID: Subject: Re: [PATCH net-next] net: page pool: allow to pass zero flags to page_pool_init() To: Jesper Dangaard Brouer Cc: netdev@vger.kernel.org, hawk@kernel.org, ilias.apalodimas@linaro.org Content-Type: text/plain; charset="UTF-8" Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On 3/25/20, Jesper Dangaard Brouer wrote: > On Wed, 25 Mar 2020 17:12:55 +0300 > Denis Kirjanov wrote: > >> page pool API can be useful for non-DMA cases like >> xen-netfront driver so let's allow to pass zero flags to >> page pool flags. >> >> Signed-off-by: Denis Kirjanov >> --- >> net/core/page_pool.c | 36 +++++++++++++++++++----------------- >> 1 file changed, 19 insertions(+), 17 deletions(-) > > The pool->p.dma_dir is only used when flag PP_FLAG_DMA_MAP is used, so > it looks more simple to do: Yeap, agreed. Thanks! > > $ git diff > diff --git a/net/core/page_pool.c b/net/core/page_pool.c > index 626db912fce4..ef98372facf6 100644 > --- a/net/core/page_pool.c > +++ b/net/core/page_pool.c > @@ -43,9 +43,11 @@ static int page_pool_init(struct page_pool *pool, > * DMA_BIDIRECTIONAL is for allowing page used for DMA sending, > * which is the XDP_TX use-case. > */ > - if ((pool->p.dma_dir != DMA_FROM_DEVICE) && > - (pool->p.dma_dir != DMA_BIDIRECTIONAL)) > - return -EINVAL; > + if (pool->p.flags & PP_FLAG_DMA_MAP) { > + if ((pool->p.dma_dir != DMA_FROM_DEVICE) && > + (pool->p.dma_dir != DMA_BIDIRECTIONAL)) > + return -EINVAL; > + } > > > >> diff --git a/net/core/page_pool.c b/net/core/page_pool.c >> index 10d2b25..eeeb0d9 100644 >> --- a/net/core/page_pool.c >> +++ b/net/core/page_pool.c >> @@ -39,27 +39,29 @@ static int page_pool_init(struct page_pool *pool, >> if (ring_qsize > 32768) >> return -E2BIG; >> >> - /* DMA direction is either DMA_FROM_DEVICE or DMA_BIDIRECTIONAL. >> - * DMA_BIDIRECTIONAL is for allowing page used for DMA sending, >> - * which is the XDP_TX use-case. >> - */ >> - if ((pool->p.dma_dir != DMA_FROM_DEVICE) && >> - (pool->p.dma_dir != DMA_BIDIRECTIONAL)) >> - return -EINVAL; >> - >> - if (pool->p.flags & PP_FLAG_DMA_SYNC_DEV) { >> - /* In order to request DMA-sync-for-device the page >> - * needs to be mapped >> + if (pool->p.flags) { >> + /* DMA direction is either DMA_FROM_DEVICE or DMA_BIDIRECTIONAL. >> + * DMA_BIDIRECTIONAL is for allowing page used for DMA sending, >> + * which is the XDP_TX use-case. >> */ >> - if (!(pool->p.flags & PP_FLAG_DMA_MAP)) >> + if ((pool->p.dma_dir != DMA_FROM_DEVICE) && >> + (pool->p.dma_dir != DMA_BIDIRECTIONAL)) >> return -EINVAL; >> >> - if (!pool->p.max_len) >> - return -EINVAL; >> + if (pool->p.flags & PP_FLAG_DMA_SYNC_DEV) { >> + /* In order to request DMA-sync-for-device the page >> + * needs to be mapped >> + */ >> + if (!(pool->p.flags & PP_FLAG_DMA_MAP)) >> + return -EINVAL; >> >> - /* pool->p.offset has to be set according to the address >> - * offset used by the DMA engine to start copying rx data >> - */ >> + if (!pool->p.max_len) >> + return -EINVAL; >> + >> + /* pool->p.offset has to be set according to the address >> + * offset used by the DMA engine to start copying rx data >> + */ >> + } >> } >> >> if (ptr_ring_init(&pool->ring, ring_qsize, GFP_KERNEL) < 0) > > > > -- > Best regards, > Jesper Dangaard Brouer > MSc.CS, Principal Kernel Engineer at Red Hat > LinkedIn: http://www.linkedin.com/in/brouer > >