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=-6.9 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, 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 DE661C43441 for ; Sat, 17 Nov 2018 07:06:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 968FB2084C for ; Sat, 17 Nov 2018 07:06:51 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="d1vIDkbe" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 968FB2084C Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725927AbeKQRWc (ORCPT ); Sat, 17 Nov 2018 12:22:32 -0500 Received: from mail-lj1-f193.google.com ([209.85.208.193]:34908 "EHLO mail-lj1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725810AbeKQRWc (ORCPT ); Sat, 17 Nov 2018 12:22:32 -0500 Received: by mail-lj1-f193.google.com with SMTP id x85-v6so22242720ljb.2 for ; Fri, 16 Nov 2018 23:06:48 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=fIKcjyDRicTrvbuurk8pmEnO8fySvmZKHCB2aFwXKyo=; b=d1vIDkbeZUZUCYskR8G7+3qH2MMSz6P51FBjnG/CkqJ7iWaUY9dyicU2YmH6olA42D Sp5JkcRb397m5fl5zZFVJY+eNi77Lps6tbR4yk7IXiUOT+CvsbSmn0C1eNXACcYw4zR1 fMC3t03xr4Cnqf0749ChMGV88OFtE8sqiFGN5VedJl4L5e0SEscrTTPRjJpXVABBM/Nc DykZpAZ/xLephvYBoA7UGbBJMX7baxyhg7y6GPb1JyIxSKN+uRsH6271lLw/3TrF/k5d IiSXtuQY6TZAMsMAqvGrLMiaXdTywSthefBge9GBj5WY5CGxqscf/FcMcih0KPMYwf/O xdyg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=fIKcjyDRicTrvbuurk8pmEnO8fySvmZKHCB2aFwXKyo=; b=mC4j1sglfQklPTkLfLrxTGkw10jgLtLxmTmrRb/yf1E6BOG3p/QLGIQz+OjY+1GQ4B ofKSmFw7uiMpmuvdXnNRHeD1cIMacGq8kDfVyXtahD8gK4ZMX5GCfVgs7x8cqffvD+yD vYcTLK1zEdh1xiVV4JOPUV1Vt6UDNHVfXQMDhfgyxBjwZYilGqaZYSn/rxCBsf9x2mQt 3idTtxyGcXMzu1oAkBNZ9VGOi/uejdmBMk/uDoKJQf3K5aaZW9y22ZodVm30YqhwLJtl WiWNUkQn2dy5eOdZpBQopBCuIiiy2eOnshNRQKNkhkYf8JYNqHW3xY1kqdQl2ujvuHQi OKsg== X-Gm-Message-State: AGRZ1gJkcM0gTHcEd1qu5nVIRZivwJFnegY+89sBjw8/shufu/pdlw37 n91AE9RsYJalhOclGY0uqa+xneV0q4rAV7AM24Q= X-Google-Smtp-Source: AJdET5czjaiMsHoTtcU3ldJi6TO+PftdpUiKXZ88r8b39gmA5paMZgOKfehDa96kXsV8gIx4bI6GqpsYsVHngdTtUTo= X-Received: by 2002:a2e:9b84:: with SMTP id z4-v6mr7425061lji.93.1542438407249; Fri, 16 Nov 2018 23:06:47 -0800 (PST) MIME-Version: 1.0 References: <5bdfb8db.1c69fb81.c8f62.9586@mx.google.com> <7a3922bc5089dfe0978e07a809606360c74c940c.camel@perches.com> In-Reply-To: <7a3922bc5089dfe0978e07a809606360c74c940c.camel@perches.com> From: Souptick Joarder Date: Sat, 17 Nov 2018 12:40:14 +0530 Message-ID: Subject: Re: [PATCH] arch/powerpc: Use dma_zalloc_coherent To: Joe Perches Cc: Sabyasachi Gupta , benh@kernel.crashing.org, paulus@samba.org, mpe@ellerman.id.au, darren@stevens-zone.net, christophe.leroy@c-s.fr, geoff@infradead.org, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Joe, On Fri, Nov 16, 2018 at 12:55 AM Joe Perches wrote: > > On Thu, 2018-11-15 at 23:29 +0530, Sabyasachi Gupta wrote: > > On Mon, Nov 5, 2018 at 8:58 AM Sabyasachi Gupta > > wrote: > > > Replaced dma_alloc_coherent + memset with dma_zalloc_coherent > > > > > > Signed-off-by: Sabyasachi Gupta > > > > Any comment on this patch? > > It's obviously correct. > > You might realign the arguments on the next lines > to the open parenthesis. > > Perhaps there should be new function calls > added for symmetry to the other alloc functions > for multiplication overflow protection. > > Perhaps: > > void *dma_alloc_array_coherent() > void *dma_calloc_coherent() > > Something like > --- > include/linux/dma-mapping.h | 19 +++++++++++++++++++ > 1 file changed, 19 insertions(+) > > diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h > index 15bd41447025..95bebf8883b1 100644 > --- a/include/linux/dma-mapping.h > +++ b/include/linux/dma-mapping.h > @@ -565,6 +565,25 @@ static inline void *dma_alloc_coherent(struct device *dev, size_t size, > (gfp & __GFP_NOWARN) ? DMA_ATTR_NO_WARN : 0); > } > > +static inline void *dma_alloc_array_coherent(struct device *dev, > + size_t n, size_t size, > + dma_addr_t *dma_handle, gfp_t gfp) > +{ > + size_t bytes; > + > + if (unlikely(check_mul_overflow(n, size, &bytes))) > + return NULL; > + return dma_alloc_coherent(dev, bytes, dma_handle, gfp); > +} > + > +static inline void *dma_calloc_coherent(struct device *dev, > + size_t n, size_t size, > + dma_addr_t *dma_handle, gfp_t gfp) > +{ > + return dma_alloc_array_coherent(dev, n, size, dma_handle, > + gfp | __GFP_ZERO); > +} > + If I understood correctly, you are talking about adding these 2 new inline functions. We can do that. Can you please help to understand the consumers of these 2 new inline ? > static inline void dma_free_coherent(struct device *dev, size_t size, > void *cpu_addr, dma_addr_t dma_handle) > { > > --- > > > diff --git a/arch/powerpc/platforms/pasemi/dma_lib.c b/arch/powerpc/platforms/pasemi/dma_lib.c > [] > > > @@ -255,15 +255,13 @@ int pasemi_dma_alloc_ring(struct pasemi_dmachan *chan, int ring_size) > > > > > > chan->ring_size = ring_size; > > > > > > - chan->ring_virt = dma_alloc_coherent(&dma_pdev->dev, > > > + chan->ring_virt = dma_zalloc_coherent(&dma_pdev->dev, > > > ring_size * sizeof(u64), > > > &chan->ring_dma, GFP_KERNEL); > > > en > > > if (!chan->ring_virt) > > > return -ENOMEM; > > > > > > - memset(chan->ring_virt, 0, ring_size * sizeof(u64)); > > > - > > > return 0; > > > } > > > EXPORT_SYMBOL(pasemi_dma_alloc_ring); > >