From patchwork Fri Aug 14 10:26:23 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nicolas Saenz Julienne X-Patchwork-Id: 1287370 Return-Path: Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 66DB2C433E1 for ; Fri, 14 Aug 2020 10:26:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4A18620781 for ; Fri, 14 Aug 2020 10:26:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726919AbgHNK0g (ORCPT ); Fri, 14 Aug 2020 06:26:36 -0400 Received: from mx2.suse.de ([195.135.220.15]:54358 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726012AbgHNK0f (ORCPT ); Fri, 14 Aug 2020 06:26:35 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id B5BB5AD1A; Fri, 14 Aug 2020 10:26:56 +0000 (UTC) From: Nicolas Saenz Julienne To: amit.pundir@linaro.org, hch@lst.de, linux-kernel@vger.kernel.org, Marek Szyprowski , Robin Murphy Cc: rientjes@google.com, jeremy.linton@arm.com, linux-rpi-kernel@lists.infradead.org, Nicolas Saenz Julienne , iommu@lists.linux-foundation.org Subject: [PATCH v4 1/2] dma-pool: Only allocate from CMA when in same memory zone Date: Fri, 14 Aug 2020 12:26:23 +0200 Message-Id: <20200814102625.25599-2-nsaenzjulienne@suse.de> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200814102625.25599-1-nsaenzjulienne@suse.de> References: <20200814102625.25599-1-nsaenzjulienne@suse.de> MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org There is no guarantee to CMA's placement, so allocating a zone specific atomic pool from CMA might return memory from a completely different memory zone. To get around this double check CMA's placement before allocating from it. Signed-off-by: Nicolas Saenz Julienne [hch: rebased, added a fallback to the page allocator, allow dipping into lower CMA pools] Signed-off-by: Christoph Hellwig --- Changes since v3: - Do not use memblock_start_of_DRAM() Changes since v2: - Go back to v1 behavior kernel/dma/pool.c | 31 ++++++++++++++++++++++++++++++- 1 file changed, 30 insertions(+), 1 deletion(-) diff --git a/kernel/dma/pool.c b/kernel/dma/pool.c index 6bc74a2d5127..57f4a0f32a92 100644 --- a/kernel/dma/pool.c +++ b/kernel/dma/pool.c @@ -3,7 +3,9 @@ * Copyright (C) 2012 ARM Ltd. * Copyright (C) 2020 Google LLC */ +#include #include +#include #include #include #include @@ -55,6 +57,29 @@ static void dma_atomic_pool_size_add(gfp_t gfp, size_t size) pool_size_kernel += size; } +static bool cma_in_zone(gfp_t gfp) +{ + unsigned long size; + phys_addr_t end; + struct cma *cma; + + cma = dev_get_cma_area(NULL); + if (!cma) + return false; + + size = cma_get_size(cma); + if (!size) + return false; + + /* CMA can't cross zone boundaries, see cma_activate_area() */ + end = cma_get_base(cma) + size - 1; + if (IS_ENABLED(CONFIG_ZONE_DMA) && (gfp & GFP_DMA)) + return end <= DMA_BIT_MASK(zone_dma_bits); + if (IS_ENABLED(CONFIG_ZONE_DMA32) && (gfp & GFP_DMA32)) + return end <= DMA_BIT_MASK(32); + return true; +} + static int atomic_pool_expand(struct gen_pool *pool, size_t pool_size, gfp_t gfp) { @@ -68,7 +93,11 @@ static int atomic_pool_expand(struct gen_pool *pool, size_t pool_size, do { pool_size = 1 << (PAGE_SHIFT + order); - page = alloc_pages(gfp, order); + if (cma_in_zone(gfp)) + page = dma_alloc_from_contiguous(NULL, 1 << order, + order, false); + if (!page) + page = alloc_pages(gfp, order); } while (!page && order-- > 0); if (!page) goto out; From patchwork Fri Aug 14 10:26:24 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nicolas Saenz Julienne X-Patchwork-Id: 1287371 Return-Path: Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1B283C433E3 for ; Fri, 14 Aug 2020 10:26:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id F3F9820781 for ; Fri, 14 Aug 2020 10:26:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726948AbgHNK0k (ORCPT ); Fri, 14 Aug 2020 06:26:40 -0400 Received: from mx2.suse.de ([195.135.220.15]:54380 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726891AbgHNK0i (ORCPT ); Fri, 14 Aug 2020 06:26:38 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 9EA78AD41; Fri, 14 Aug 2020 10:26:57 +0000 (UTC) From: Nicolas Saenz Julienne To: amit.pundir@linaro.org, hch@lst.de, linux-kernel@vger.kernel.org, Joerg Roedel , Marek Szyprowski , Robin Murphy Cc: rientjes@google.com, jeremy.linton@arm.com, linux-rpi-kernel@lists.infradead.org, iommu@lists.linux-foundation.org Subject: [PATCH v4 2/2] dma-pool: fix coherent pool allocations for IOMMU mappings Date: Fri, 14 Aug 2020 12:26:24 +0200 Message-Id: <20200814102625.25599-3-nsaenzjulienne@suse.de> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200814102625.25599-1-nsaenzjulienne@suse.de> References: <20200814102625.25599-1-nsaenzjulienne@suse.de> MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Christoph Hellwig When allocating coherent pool memory for an IOMMU mapping we don't care about the DMA mask. Move the guess for the initial GFP mask into the dma_direct_alloc_pages and pass dma_coherent_ok as a function pointer argument so that it doesn't get applied to the IOMMU case. Signed-off-by: Christoph Hellwig --- Changes since v1: - Check if phys_addr_ok() exists prior calling it drivers/iommu/dma-iommu.c | 4 +- include/linux/dma-direct.h | 3 - include/linux/dma-mapping.h | 5 +- kernel/dma/direct.c | 13 ++-- kernel/dma/pool.c | 114 +++++++++++++++--------------------- 5 files changed, 62 insertions(+), 77 deletions(-) diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c index 4959f5df21bd..5141d49a046b 100644 --- a/drivers/iommu/dma-iommu.c +++ b/drivers/iommu/dma-iommu.c @@ -1035,8 +1035,8 @@ static void *iommu_dma_alloc(struct device *dev, size_t size, if (IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) && !gfpflags_allow_blocking(gfp) && !coherent) - cpu_addr = dma_alloc_from_pool(dev, PAGE_ALIGN(size), &page, - gfp); + page = dma_alloc_from_pool(dev, PAGE_ALIGN(size), &cpu_addr, + gfp, NULL); else cpu_addr = iommu_dma_alloc_pages(dev, size, &page, gfp, attrs); if (!cpu_addr) diff --git a/include/linux/dma-direct.h b/include/linux/dma-direct.h index 5a3ce2a24794..6e87225600ae 100644 --- a/include/linux/dma-direct.h +++ b/include/linux/dma-direct.h @@ -73,9 +73,6 @@ static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size, } u64 dma_direct_get_required_mask(struct device *dev); -gfp_t dma_direct_optimal_gfp_mask(struct device *dev, u64 dma_mask, - u64 *phys_mask); -bool dma_coherent_ok(struct device *dev, phys_addr_t phys, size_t size); void *dma_direct_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs); void dma_direct_free(struct device *dev, size_t size, void *cpu_addr, diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h index 016b96b384bd..52635e91143b 100644 --- a/include/linux/dma-mapping.h +++ b/include/linux/dma-mapping.h @@ -522,8 +522,9 @@ void *dma_common_pages_remap(struct page **pages, size_t size, pgprot_t prot, const void *caller); void dma_common_free_remap(void *cpu_addr, size_t size); -void *dma_alloc_from_pool(struct device *dev, size_t size, - struct page **ret_page, gfp_t flags); +struct page *dma_alloc_from_pool(struct device *dev, size_t size, + void **cpu_addr, gfp_t flags, + bool (*phys_addr_ok)(struct device *, phys_addr_t, size_t)); bool dma_free_from_pool(struct device *dev, void *start, size_t size); int diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c index bb0041e99659..db6ef07aec3b 100644 --- a/kernel/dma/direct.c +++ b/kernel/dma/direct.c @@ -43,7 +43,7 @@ u64 dma_direct_get_required_mask(struct device *dev) return (1ULL << (fls64(max_dma) - 1)) * 2 - 1; } -gfp_t dma_direct_optimal_gfp_mask(struct device *dev, u64 dma_mask, +static gfp_t dma_direct_optimal_gfp_mask(struct device *dev, u64 dma_mask, u64 *phys_limit) { u64 dma_limit = min_not_zero(dma_mask, dev->bus_dma_limit); @@ -68,7 +68,7 @@ gfp_t dma_direct_optimal_gfp_mask(struct device *dev, u64 dma_mask, return 0; } -bool dma_coherent_ok(struct device *dev, phys_addr_t phys, size_t size) +static bool dma_coherent_ok(struct device *dev, phys_addr_t phys, size_t size) { return phys_to_dma_direct(dev, phys) + size - 1 <= min_not_zero(dev->coherent_dma_mask, dev->bus_dma_limit); @@ -161,8 +161,13 @@ void *dma_direct_alloc_pages(struct device *dev, size_t size, size = PAGE_ALIGN(size); if (dma_should_alloc_from_pool(dev, gfp, attrs)) { - ret = dma_alloc_from_pool(dev, size, &page, gfp); - if (!ret) + u64 phys_mask; + + gfp |= dma_direct_optimal_gfp_mask(dev, dev->coherent_dma_mask, + &phys_mask); + page = dma_alloc_from_pool(dev, size, &ret, gfp, + dma_coherent_ok); + if (!page) return NULL; goto done; } diff --git a/kernel/dma/pool.c b/kernel/dma/pool.c index 57f4a0f32a92..b0aaba4197ae 100644 --- a/kernel/dma/pool.c +++ b/kernel/dma/pool.c @@ -225,93 +225,75 @@ static int __init dma_atomic_pool_init(void) } postcore_initcall(dma_atomic_pool_init); -static inline struct gen_pool *dma_guess_pool_from_device(struct device *dev) +static inline struct gen_pool *dma_guess_pool(struct gen_pool *prev, gfp_t gfp) { - u64 phys_mask; - gfp_t gfp; - - gfp = dma_direct_optimal_gfp_mask(dev, dev->coherent_dma_mask, - &phys_mask); - if (IS_ENABLED(CONFIG_ZONE_DMA) && gfp == GFP_DMA) + if (prev == NULL) { + if (IS_ENABLED(CONFIG_ZONE_DMA32) && (gfp & GFP_DMA32)) + return atomic_pool_dma32; + if (IS_ENABLED(CONFIG_ZONE_DMA) && (gfp & GFP_DMA)) + return atomic_pool_dma; + return atomic_pool_kernel; + } + if (prev == atomic_pool_kernel) + return atomic_pool_dma32 ? atomic_pool_dma32 : atomic_pool_dma; + if (prev == atomic_pool_dma32) return atomic_pool_dma; - if (IS_ENABLED(CONFIG_ZONE_DMA32) && gfp == GFP_DMA32) - return atomic_pool_dma32; - return atomic_pool_kernel; + return NULL; } -static inline struct gen_pool *dma_get_safer_pool(struct gen_pool *bad_pool) +static struct page *__dma_alloc_from_pool(struct device *dev, size_t size, + struct gen_pool *pool, void **cpu_addr, + bool (*phys_addr_ok)(struct device *, phys_addr_t, size_t)) { - if (bad_pool == atomic_pool_kernel) - return atomic_pool_dma32 ? : atomic_pool_dma; + unsigned long addr; + phys_addr_t phys; - if (bad_pool == atomic_pool_dma32) - return atomic_pool_dma; + addr = gen_pool_alloc(pool, size); + if (!addr) + return NULL; - return NULL; -} + phys = gen_pool_virt_to_phys(pool, addr); + if (phys_addr_ok && !phys_addr_ok(dev, phys, size)) { + gen_pool_free(pool, addr, size); + return NULL; + } -static inline struct gen_pool *dma_guess_pool(struct device *dev, - struct gen_pool *bad_pool) -{ - if (bad_pool) - return dma_get_safer_pool(bad_pool); + if (gen_pool_avail(pool) < atomic_pool_size) + schedule_work(&atomic_pool_work); - return dma_guess_pool_from_device(dev); + *cpu_addr = (void *)addr; + memset(*cpu_addr, 0, size); + return pfn_to_page(__phys_to_pfn(phys)); } -void *dma_alloc_from_pool(struct device *dev, size_t size, - struct page **ret_page, gfp_t flags) +struct page *dma_alloc_from_pool(struct device *dev, size_t size, + void **cpu_addr, gfp_t gfp, + bool (*phys_addr_ok)(struct device *, phys_addr_t, size_t)) { struct gen_pool *pool = NULL; - unsigned long val = 0; - void *ptr = NULL; - phys_addr_t phys; - - while (1) { - pool = dma_guess_pool(dev, pool); - if (!pool) { - WARN(1, "Failed to get suitable pool for %s\n", - dev_name(dev)); - break; - } - - val = gen_pool_alloc(pool, size); - if (!val) - continue; - - phys = gen_pool_virt_to_phys(pool, val); - if (dma_coherent_ok(dev, phys, size)) - break; - - gen_pool_free(pool, val, size); - val = 0; - } - - - if (val) { - *ret_page = pfn_to_page(__phys_to_pfn(phys)); - ptr = (void *)val; - memset(ptr, 0, size); + struct page *page; - if (gen_pool_avail(pool) < atomic_pool_size) - schedule_work(&atomic_pool_work); + while ((pool = dma_guess_pool(pool, gfp))) { + page = __dma_alloc_from_pool(dev, size, pool, cpu_addr, + phys_addr_ok); + if (page) + return page; } - return ptr; + WARN(1, "Failed to get suitable pool for %s\n", dev_name(dev)); + return NULL; } bool dma_free_from_pool(struct device *dev, void *start, size_t size) { struct gen_pool *pool = NULL; - while (1) { - pool = dma_guess_pool(dev, pool); - if (!pool) - return false; - - if (gen_pool_has_addr(pool, (unsigned long)start, size)) { - gen_pool_free(pool, (unsigned long)start, size); - return true; - } + while ((pool = dma_guess_pool(pool, 0))) { + if (!gen_pool_has_addr(pool, (unsigned long)start, size)) + continue; + gen_pool_free(pool, (unsigned long)start, size); + return true; } + + return false; }