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=-8.5 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,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 E08C0C64EB4 for ; Fri, 30 Nov 2018 19:05:14 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id B013B20673 for ; Fri, 30 Nov 2018 19:05:14 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="VhV+YrJQ" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B013B20673 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender:Content-Type: Content-Transfer-Encoding:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:Date:Message-ID:From: References:To:Subject:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=q/qbC3cZKFYhesfTlM0Y+YNpBOjx89bH4wMJyZEAb7w=; b=VhV+YrJQDuPIEGCt1nYvaLKAY MO7+P7IFW4ovo3oVqrJ043qTl08b6zJGAlBk6lansYLhYPwROSjq6PB9Na6kSRsSmNRJ7zOZo60b8 vDVy3yCEd6q5ie2LIjPEwk7ytcGLVvChEgbjGdpwv5F43tP0Aiu9lzaHTrtpjvXsk68PCsfJUDH3j Sbaozac3MHICDsTUs+/8wa1OE6RiEHUnOHoRFs27xNz+H6mnVDRTM/KJ4glCDfZYoBrPOtfcJ9KPZ wbz3Yy9sogJgigC7QOsFT+wA1Gj/xXpi71TYFJQPmcAXrAvo4NmtXHn2jjRdO/1Sk00bnsxW683p4 wiJRMYYwA==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1gSo6A-0001nu-5I; Fri, 30 Nov 2018 19:05:10 +0000 Received: from foss.arm.com ([217.140.101.70]) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1gSo5w-0001Kl-Cu for linux-arm-kernel@lists.infradead.org; Fri, 30 Nov 2018 19:04:57 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 2B611165C; Fri, 30 Nov 2018 11:04:44 -0800 (PST) Received: from [10.1.196.75] (e110467-lin.cambridge.arm.com [10.1.196.75]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id C7AFA3F575; Fri, 30 Nov 2018 11:04:42 -0800 (PST) Subject: Re: [PATCH 1/9] dma-direct: provide page based alloc/free helpers To: Christoph Hellwig , iommu@lists.linux-foundation.org References: <20181105121931.13481-1-hch@lst.de> <20181105121931.13481-2-hch@lst.de> From: Robin Murphy Message-ID: <3b6439f3-fb7e-aaf7-01b9-b0fb03a27a69@arm.com> Date: Fri, 30 Nov 2018 19:04:41 +0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.2.1 MIME-Version: 1.0 In-Reply-To: <20181105121931.13481-2-hch@lst.de> Content-Language: en-GB X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20181130_110456_449655_D239A7D8 X-CRM114-Status: GOOD ( 23.36 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Catalin Marinas , Will Deacon , linux-kernel@vger.kernel.org, Guo Ren , Laura Abbott , linux-arm-kernel@lists.infradead.org Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 05/11/2018 12:19, Christoph Hellwig wrote: > Some architectures support remapping highmem into DMA coherent > allocations. To use the common code for them we need variants of > dma_direct_{alloc,free}_pages that do not use kernel virtual addresses. FWIW it's as much about non-cacheable remapping of lowmem as it is about highmem. Regardless, the diff looks OK to me. Reviewed-by: Robin Murphy > Signed-off-by: Christoph Hellwig > --- > include/linux/dma-direct.h | 3 +++ > kernel/dma/direct.c | 32 ++++++++++++++++++++++---------- > 2 files changed, 25 insertions(+), 10 deletions(-) > > diff --git a/include/linux/dma-direct.h b/include/linux/dma-direct.h > index bd73e7a91410..5a7a3bbb912f 100644 > --- a/include/linux/dma-direct.h > +++ b/include/linux/dma-direct.h > @@ -67,6 +67,9 @@ void *dma_direct_alloc_pages(struct device *dev, size_t size, > dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs); > void dma_direct_free_pages(struct device *dev, size_t size, void *cpu_addr, > dma_addr_t dma_addr, unsigned long attrs); > +struct page *__dma_direct_alloc_pages(struct device *dev, size_t size, > + dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs); > +void __dma_direct_free_pages(struct device *dev, size_t size, struct page *page); > dma_addr_t dma_direct_map_page(struct device *dev, struct page *page, > unsigned long offset, size_t size, enum dma_data_direction dir, > unsigned long attrs); > diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c > index 22a12ab5a5e9..680287779b0a 100644 > --- a/kernel/dma/direct.c > +++ b/kernel/dma/direct.c > @@ -103,14 +103,13 @@ static bool dma_coherent_ok(struct device *dev, phys_addr_t phys, size_t size) > min_not_zero(dev->coherent_dma_mask, dev->bus_dma_mask); > } > > -void *dma_direct_alloc_pages(struct device *dev, size_t size, > +struct page *__dma_direct_alloc_pages(struct device *dev, size_t size, > dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs) > { > unsigned int count = PAGE_ALIGN(size) >> PAGE_SHIFT; > int page_order = get_order(size); > struct page *page = NULL; > u64 phys_mask; > - void *ret; > > if (attrs & DMA_ATTR_NO_WARN) > gfp |= __GFP_NOWARN; > @@ -150,11 +149,22 @@ void *dma_direct_alloc_pages(struct device *dev, size_t size, > } > } > > + return page; > +} > + > +void *dma_direct_alloc_pages(struct device *dev, size_t size, > + dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs) > +{ > + struct page *page; > + void *ret; > + > + page = __dma_direct_alloc_pages(dev, size, dma_handle, gfp, attrs); > if (!page) > return NULL; > + > ret = page_address(page); > if (force_dma_unencrypted()) { > - set_memory_decrypted((unsigned long)ret, 1 << page_order); > + set_memory_decrypted((unsigned long)ret, 1 << get_order(size)); > *dma_handle = __phys_to_dma(dev, page_to_phys(page)); > } else { > *dma_handle = phys_to_dma(dev, page_to_phys(page)); > @@ -163,20 +173,22 @@ void *dma_direct_alloc_pages(struct device *dev, size_t size, > return ret; > } > > -/* > - * NOTE: this function must never look at the dma_addr argument, because we want > - * to be able to use it as a helper for iommu implementations as well. > - */ > +void __dma_direct_free_pages(struct device *dev, size_t size, struct page *page) > +{ > + unsigned int count = PAGE_ALIGN(size) >> PAGE_SHIFT; > + > + if (!dma_release_from_contiguous(dev, page, count)) > + __free_pages(page, get_order(size)); > +} > + > void dma_direct_free_pages(struct device *dev, size_t size, void *cpu_addr, > dma_addr_t dma_addr, unsigned long attrs) > { > - unsigned int count = PAGE_ALIGN(size) >> PAGE_SHIFT; > unsigned int page_order = get_order(size); > > if (force_dma_unencrypted()) > set_memory_encrypted((unsigned long)cpu_addr, 1 << page_order); > - if (!dma_release_from_contiguous(dev, virt_to_page(cpu_addr), count)) > - free_pages((unsigned long)cpu_addr, page_order); > + __dma_direct_free_pages(dev, size, virt_to_page(cpu_addr)); > } > > void *dma_direct_alloc(struct device *dev, size_t size, > _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel