From patchwork Tue Feb 3 08:47:32 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Carlo Caione X-Patchwork-Id: 5767011 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 94D74BF440 for ; Tue, 3 Feb 2015 08:50:31 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 6D23D20B70 for ; Tue, 3 Feb 2015 08:50:30 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 54E0320B6F for ; Tue, 3 Feb 2015 08:50:29 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1YIZAB-0007jC-O9; Tue, 03 Feb 2015 08:48:51 +0000 Received: from mail-wg0-x22f.google.com ([2a00:1450:400c:c00::22f]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1YIZ9t-00072b-MM for linux-arm-kernel@lists.infradead.org; Tue, 03 Feb 2015 08:48:36 +0000 Received: by mail-wg0-f47.google.com with SMTP id n12so43288011wgh.6 for ; Tue, 03 Feb 2015 00:48:11 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=sender:from:to:cc:subject:date:message-id:in-reply-to:references; bh=n3GXYxUbVCp8wdYUPTE2s0V3i8TDtsGcjyFbnBMxqiI=; b=vucKq0AHQsLrA6106FagER5gw1KVLafXVTKu1IKYAJ/a0a2VM3gdLfd8G4k9i1r0DH GyQSk3edG4YgvzQkRhRelz0a5Bcj+EpECWuE+RW7SXSDHbpe+U/A7vLLV+K9sacdG2ma p+2/C2XlQEIy/Hs9C+TrRRat9IoIYpJoNcrifvluz/IqLPT8Os06B/TwdatYgP5XaeXY x5qScn5QffE9e3PQSkGq0RJGFeky4fT6V0vy7e8TKuxp6SO8HRc90CXEt4p5uSUf89M9 tj6GnVPXJQijZmlSRaqrplFHS7v8Qk9wYRObWIL/g6LOr/sjp4riFfKVV1GqUNBBtfIr qHQQ== X-Received: by 10.180.189.52 with SMTP id gf20mr31890976wic.27.1422953291855; Tue, 03 Feb 2015 00:48:11 -0800 (PST) Received: from nuc.localdomain (2-238-57-164.ip242.fastwebnet.it. [2.238.57.164]) by mx.google.com with ESMTPSA id n1sm15608126wib.11.2015.02.03.00.48.10 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Tue, 03 Feb 2015 00:48:11 -0800 (PST) From: Carlo Caione To: linux-arm-kernel@lists.infradead.org, jstpierre@mecheye.net, drake@endlessm.com, linux@arm.linux.org.uk, m.szyprowski@samsung.com, robdclark@gmail.com, inki.dae@samsung.com, linux-samsung-soc@vger.kernel.org, sw0312.kim@samsung.com, kgene@kernel.org, jy0922.shim@samsung.com Subject: [PATCH 2/2] arm/dma-mapping: Respect NO_KERNEL_MAPPING when we don't have an IOMMU Date: Tue, 3 Feb 2015 09:47:32 +0100 Message-Id: <1422953252-10835-3-git-send-email-carlo@caione.org> X-Mailer: git-send-email 2.2.2 In-Reply-To: <1422953252-10835-1-git-send-email-carlo@caione.org> References: <1422953252-10835-1-git-send-email-carlo@caione.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20150203_004834_020599_A70509C6 X-CRM114-Status: GOOD ( 19.40 ) X-Spam-Score: -0.7 (/) Cc: Carlo Caione X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-4.1 required=5.0 tests=BAYES_00,DKIM_SIGNED, RCVD_IN_DNSWL_MED, T_DKIM_INVALID, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: "Jasper St. Pierre" Even without an iommu, NO_KERNEL_MAPPING is still convenient to save on kernel address space in places where we don't need a kernel mapping. Implement support for it in the two places where we're creating an expensive mapping. __alloc_from_pool uses an internal pool from which we already have virtual addresses, so it's not relevant, and __alloc_simple_buffer uses alloc_pages, which will always return a lowmem page, which is already mapped into kernel space, so we can't prevent a mapping for it in that case. Signed-off-by: Jasper St. Pierre Signed-off-by: Carlo Caione Reviewed-by: Rob Clark Reviewed-by: Daniel Drake --- arch/arm/mm/dma-mapping.c | 67 +++++++++++++++++++++++++++++------------------ 1 file changed, 41 insertions(+), 26 deletions(-) diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c index a673c7f..6843293 100644 --- a/arch/arm/mm/dma-mapping.c +++ b/arch/arm/mm/dma-mapping.c @@ -289,11 +289,11 @@ static void __dma_free_buffer(struct page *page, size_t size) static void *__alloc_from_contiguous(struct device *dev, size_t size, pgprot_t prot, struct page **ret_page, - const void *caller); + const void *caller, bool want_vaddr); static void *__alloc_remap_buffer(struct device *dev, size_t size, gfp_t gfp, pgprot_t prot, struct page **ret_page, - const void *caller); + const void *caller, bool want_vaddr); static void * __dma_alloc_remap(struct page *page, size_t size, gfp_t gfp, pgprot_t prot, @@ -357,10 +357,10 @@ static int __init atomic_pool_init(void) if (dev_get_cma_area(NULL)) ptr = __alloc_from_contiguous(NULL, atomic_pool_size, prot, - &page, atomic_pool_init); + &page, atomic_pool_init, true); else ptr = __alloc_remap_buffer(NULL, atomic_pool_size, gfp, prot, - &page, atomic_pool_init); + &page, atomic_pool_init, true); if (ptr) { int ret; @@ -467,13 +467,15 @@ static void __dma_remap(struct page *page, size_t size, pgprot_t prot) static void *__alloc_remap_buffer(struct device *dev, size_t size, gfp_t gfp, pgprot_t prot, struct page **ret_page, - const void *caller) + const void *caller, bool want_vaddr) { struct page *page; - void *ptr; + void *ptr = NULL; page = __dma_alloc_buffer(dev, size, gfp); if (!page) return NULL; + if (!want_vaddr) + goto out; ptr = __dma_alloc_remap(page, size, gfp, prot, caller); if (!ptr) { @@ -481,6 +483,7 @@ static void *__alloc_remap_buffer(struct device *dev, size_t size, gfp_t gfp, return NULL; } + out: *ret_page = page; return ptr; } @@ -523,12 +526,12 @@ static int __free_from_pool(void *start, size_t size) static void *__alloc_from_contiguous(struct device *dev, size_t size, pgprot_t prot, struct page **ret_page, - const void *caller) + const void *caller, bool want_vaddr) { unsigned long order = get_order(size); size_t count = size >> PAGE_SHIFT; struct page *page; - void *ptr; + void *ptr = NULL; page = dma_alloc_from_contiguous(dev, count, order); if (!page) @@ -536,6 +539,9 @@ static void *__alloc_from_contiguous(struct device *dev, size_t size, __dma_clear_buffer(page, size); + if (!want_vaddr) + goto out; + if (PageHighMem(page)) { ptr = __dma_alloc_remap(page, size, GFP_KERNEL, prot, caller); if (!ptr) { @@ -546,17 +552,21 @@ static void *__alloc_from_contiguous(struct device *dev, size_t size, __dma_remap(page, size, prot); ptr = page_address(page); } + + out: *ret_page = page; return ptr; } static void __free_from_contiguous(struct device *dev, struct page *page, - void *cpu_addr, size_t size) + void *cpu_addr, size_t size, bool want_vaddr) { - if (PageHighMem(page)) - __dma_free_remap(cpu_addr, size); - else - __dma_remap(page, size, PAGE_KERNEL); + if (want_vaddr) { + if (PageHighMem(page)) + __dma_free_remap(cpu_addr, size); + else + __dma_remap(page, size, PAGE_KERNEL); + } dma_release_from_contiguous(dev, page, size >> PAGE_SHIFT); } @@ -574,12 +584,12 @@ static inline pgprot_t __get_dma_pgprot(struct dma_attrs *attrs, pgprot_t prot) #define nommu() 1 -#define __get_dma_pgprot(attrs, prot) __pgprot(0) -#define __alloc_remap_buffer(dev, size, gfp, prot, ret, c) NULL +#define __get_dma_pgprot(attrs, prot) __pgprot(0) +#define __alloc_remap_buffer(dev, size, gfp, prot, ret, c, wv) NULL #define __alloc_from_pool(size, ret_page) NULL -#define __alloc_from_contiguous(dev, size, prot, ret, c) NULL +#define __alloc_from_contiguous(dev, size, prot, ret, c, wv) NULL #define __free_from_pool(cpu_addr, size) 0 -#define __free_from_contiguous(dev, page, cpu_addr, size) do { } while (0) +#define __free_from_contiguous(dev, page, cpu_addr, size, wv) do { } while (0) #define __dma_free_remap(cpu_addr, size) do { } while (0) #endif /* CONFIG_MMU */ @@ -599,11 +609,13 @@ static void *__alloc_simple_buffer(struct device *dev, size_t size, gfp_t gfp, static void *__dma_alloc(struct device *dev, size_t size, dma_addr_t *handle, - gfp_t gfp, pgprot_t prot, bool is_coherent, const void *caller) + gfp_t gfp, pgprot_t prot, bool is_coherent, + struct dma_attrs *attrs, const void *caller) { u64 mask = get_coherent_dma_mask(dev); struct page *page = NULL; void *addr; + bool want_vaddr; #ifdef CONFIG_DMA_API_DEBUG u64 limit = (mask + 1) & ~mask; @@ -631,20 +643,21 @@ static void *__dma_alloc(struct device *dev, size_t size, dma_addr_t *handle, *handle = DMA_ERROR_CODE; size = PAGE_ALIGN(size); + want_vaddr = !dma_get_attr(DMA_ATTR_NO_KERNEL_MAPPING, attrs); if (is_coherent || nommu()) addr = __alloc_simple_buffer(dev, size, gfp, &page); else if (!(gfp & __GFP_WAIT)) addr = __alloc_from_pool(size, &page); else if (!dev_get_cma_area(dev)) - addr = __alloc_remap_buffer(dev, size, gfp, prot, &page, caller); + addr = __alloc_remap_buffer(dev, size, gfp, prot, &page, caller, want_vaddr); else - addr = __alloc_from_contiguous(dev, size, prot, &page, caller); + addr = __alloc_from_contiguous(dev, size, prot, &page, caller, want_vaddr); - if (addr) + if (page) *handle = pfn_to_dma(dev, page_to_pfn(page)); - return addr; + return want_vaddr ? addr : &page; } /* @@ -661,7 +674,7 @@ void *arm_dma_alloc(struct device *dev, size_t size, dma_addr_t *handle, return memory; return __dma_alloc(dev, size, handle, gfp, prot, false, - __builtin_return_address(0)); + attrs, __builtin_return_address(0)); } static void *arm_coherent_dma_alloc(struct device *dev, size_t size, @@ -674,7 +687,7 @@ static void *arm_coherent_dma_alloc(struct device *dev, size_t size, return memory; return __dma_alloc(dev, size, handle, gfp, prot, true, - __builtin_return_address(0)); + attrs, __builtin_return_address(0)); } /* @@ -715,6 +728,7 @@ static void __arm_dma_free(struct device *dev, size_t size, void *cpu_addr, bool is_coherent) { struct page *page = pfn_to_page(dma_to_pfn(dev, handle)); + bool want_vaddr = !dma_get_attr(DMA_ATTR_NO_KERNEL_MAPPING, attrs); if (dma_release_from_coherent(dev, get_order(size), cpu_addr)) return; @@ -726,14 +740,15 @@ static void __arm_dma_free(struct device *dev, size_t size, void *cpu_addr, } else if (__free_from_pool(cpu_addr, size)) { return; } else if (!dev_get_cma_area(dev)) { - __dma_free_remap(cpu_addr, size); + if (want_vaddr) + __dma_free_remap(cpu_addr, size); __dma_free_buffer(page, size); } else { /* * Non-atomic allocations cannot be freed with IRQs disabled */ WARN_ON(irqs_disabled()); - __free_from_contiguous(dev, page, cpu_addr, size); + __free_from_contiguous(dev, page, cpu_addr, size, want_vaddr); } }