From: Christoph Hellwig Date: Tue, 12 Jun 2018 17:01:45 +0000 (+0200) Subject: dma-mapping: move all DMA mapping code to kernel/dma X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=cf65a0f6f6ff7631ba0ac0513a14ca5b65320d80;p=openwrt%2Fstaging%2Fblogic.git dma-mapping: move all DMA mapping code to kernel/dma Currently the code is split over various files with dma- prefixes in the lib/ and drives/base directories, and the number of files keeps growing. Move them into a single directory to keep the code together and remove the file name prefixes. To match the irq infrastructure this directory is placed under the kernel/ directory. Signed-off-by: Christoph Hellwig --- diff --git a/Documentation/driver-api/infrastructure.rst b/Documentation/driver-api/infrastructure.rst index bee1b9a1702f..6172f3cc3d0b 100644 --- a/Documentation/driver-api/infrastructure.rst +++ b/Documentation/driver-api/infrastructure.rst @@ -49,10 +49,10 @@ Device Drivers Base Device Drivers DMA Management ----------------------------- -.. kernel-doc:: drivers/base/dma-coherent.c +.. kernel-doc:: kernel/dma/coherent.c :export: -.. kernel-doc:: drivers/base/dma-mapping.c +.. kernel-doc:: kernel/dma/mapping.c :export: Device drivers PnP support diff --git a/MAINTAINERS b/MAINTAINERS index c13b9fb3be0b..a6844a9e2f64 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -4359,12 +4359,7 @@ L: iommu@lists.linux-foundation.org T: git git://git.infradead.org/users/hch/dma-mapping.git W: http://git.infradead.org/users/hch/dma-mapping.git S: Supported -F: lib/dma-debug.c -F: lib/dma-direct.c -F: lib/dma-noncoherent.c -F: lib/dma-virt.c -F: drivers/base/dma-mapping.c -F: drivers/base/dma-coherent.c +F: kernel/dma/ F: include/asm-generic/dma-mapping.h F: include/linux/dma-direct.h F: include/linux/dma-mapping.h @@ -13642,7 +13637,7 @@ M: Konrad Rzeszutek Wilk L: iommu@lists.linux-foundation.org T: git git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb.git S: Supported -F: lib/swiotlb.c +F: kernel/dma/swiotlb.c F: arch/*/kernel/pci-swiotlb.c F: include/linux/swiotlb.h diff --git a/drivers/base/Makefile b/drivers/base/Makefile index b074f242a435..704f44295810 100644 --- a/drivers/base/Makefile +++ b/drivers/base/Makefile @@ -8,10 +8,7 @@ obj-y := component.o core.o bus.o dd.o syscore.o \ topology.o container.o property.o cacheinfo.o \ devcon.o obj-$(CONFIG_DEVTMPFS) += devtmpfs.o -obj-$(CONFIG_DMA_CMA) += dma-contiguous.o obj-y += power/ -obj-$(CONFIG_HAS_DMA) += dma-mapping.o -obj-$(CONFIG_HAVE_GENERIC_DMA_COHERENT) += dma-coherent.o obj-$(CONFIG_ISA_BUS_API) += isa.o obj-y += firmware_loader/ obj-$(CONFIG_NUMA) += node.o diff --git a/drivers/base/dma-coherent.c b/drivers/base/dma-coherent.c deleted file mode 100644 index 597d40893862..000000000000 --- a/drivers/base/dma-coherent.c +++ /dev/null @@ -1,434 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 -/* - * Coherent per-device memory handling. - * Borrowed from i386 - */ -#include -#include -#include -#include -#include - -struct dma_coherent_mem { - void *virt_base; - dma_addr_t device_base; - unsigned long pfn_base; - int size; - int flags; - unsigned long *bitmap; - spinlock_t spinlock; - bool use_dev_dma_pfn_offset; -}; - -static struct dma_coherent_mem *dma_coherent_default_memory __ro_after_init; - -static inline struct dma_coherent_mem *dev_get_coherent_memory(struct device *dev) -{ - if (dev && dev->dma_mem) - return dev->dma_mem; - return NULL; -} - -static inline dma_addr_t dma_get_device_base(struct device *dev, - struct dma_coherent_mem * mem) -{ - if (mem->use_dev_dma_pfn_offset) - return (mem->pfn_base - dev->dma_pfn_offset) << PAGE_SHIFT; - else - return mem->device_base; -} - -static int dma_init_coherent_memory( - phys_addr_t phys_addr, dma_addr_t device_addr, size_t size, int flags, - struct dma_coherent_mem **mem) -{ - struct dma_coherent_mem *dma_mem = NULL; - void __iomem *mem_base = NULL; - int pages = size >> PAGE_SHIFT; - int bitmap_size = BITS_TO_LONGS(pages) * sizeof(long); - int ret; - - if (!size) { - ret = -EINVAL; - goto out; - } - - mem_base = memremap(phys_addr, size, MEMREMAP_WC); - if (!mem_base) { - ret = -EINVAL; - goto out; - } - dma_mem = kzalloc(sizeof(struct dma_coherent_mem), GFP_KERNEL); - if (!dma_mem) { - ret = -ENOMEM; - goto out; - } - dma_mem->bitmap = kzalloc(bitmap_size, GFP_KERNEL); - if (!dma_mem->bitmap) { - ret = -ENOMEM; - goto out; - } - - dma_mem->virt_base = mem_base; - dma_mem->device_base = device_addr; - dma_mem->pfn_base = PFN_DOWN(phys_addr); - dma_mem->size = pages; - dma_mem->flags = flags; - spin_lock_init(&dma_mem->spinlock); - - *mem = dma_mem; - return 0; - -out: - kfree(dma_mem); - if (mem_base) - memunmap(mem_base); - return ret; -} - -static void dma_release_coherent_memory(struct dma_coherent_mem *mem) -{ - if (!mem) - return; - - memunmap(mem->virt_base); - kfree(mem->bitmap); - kfree(mem); -} - -static int dma_assign_coherent_memory(struct device *dev, - struct dma_coherent_mem *mem) -{ - if (!dev) - return -ENODEV; - - if (dev->dma_mem) - return -EBUSY; - - dev->dma_mem = mem; - return 0; -} - -int dma_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr, - dma_addr_t device_addr, size_t size, int flags) -{ - struct dma_coherent_mem *mem; - int ret; - - ret = dma_init_coherent_memory(phys_addr, device_addr, size, flags, &mem); - if (ret) - return ret; - - ret = dma_assign_coherent_memory(dev, mem); - if (ret) - dma_release_coherent_memory(mem); - return ret; -} -EXPORT_SYMBOL(dma_declare_coherent_memory); - -void dma_release_declared_memory(struct device *dev) -{ - struct dma_coherent_mem *mem = dev->dma_mem; - - if (!mem) - return; - dma_release_coherent_memory(mem); - dev->dma_mem = NULL; -} -EXPORT_SYMBOL(dma_release_declared_memory); - -void *dma_mark_declared_memory_occupied(struct device *dev, - dma_addr_t device_addr, size_t size) -{ - struct dma_coherent_mem *mem = dev->dma_mem; - unsigned long flags; - int pos, err; - - size += device_addr & ~PAGE_MASK; - - if (!mem) - return ERR_PTR(-EINVAL); - - spin_lock_irqsave(&mem->spinlock, flags); - pos = PFN_DOWN(device_addr - dma_get_device_base(dev, mem)); - err = bitmap_allocate_region(mem->bitmap, pos, get_order(size)); - spin_unlock_irqrestore(&mem->spinlock, flags); - - if (err != 0) - return ERR_PTR(err); - return mem->virt_base + (pos << PAGE_SHIFT); -} -EXPORT_SYMBOL(dma_mark_declared_memory_occupied); - -static void *__dma_alloc_from_coherent(struct dma_coherent_mem *mem, - ssize_t size, dma_addr_t *dma_handle) -{ - int order = get_order(size); - unsigned long flags; - int pageno; - void *ret; - - spin_lock_irqsave(&mem->spinlock, flags); - - if (unlikely(size > (mem->size << PAGE_SHIFT))) - goto err; - - pageno = bitmap_find_free_region(mem->bitmap, mem->size, order); - if (unlikely(pageno < 0)) - goto err; - - /* - * Memory was found in the coherent area. - */ - *dma_handle = mem->device_base + (pageno << PAGE_SHIFT); - ret = mem->virt_base + (pageno << PAGE_SHIFT); - spin_unlock_irqrestore(&mem->spinlock, flags); - memset(ret, 0, size); - return ret; -err: - spin_unlock_irqrestore(&mem->spinlock, flags); - return NULL; -} - -/** - * dma_alloc_from_dev_coherent() - allocate memory from device coherent pool - * @dev: device from which we allocate memory - * @size: size of requested memory area - * @dma_handle: This will be filled with the correct dma handle - * @ret: This pointer will be filled with the virtual address - * to allocated area. - * - * This function should be only called from per-arch dma_alloc_coherent() - * to support allocation from per-device coherent memory pools. - * - * Returns 0 if dma_alloc_coherent should continue with allocating from - * generic memory areas, or !0 if dma_alloc_coherent should return @ret. - */ -int dma_alloc_from_dev_coherent(struct device *dev, ssize_t size, - dma_addr_t *dma_handle, void **ret) -{ - struct dma_coherent_mem *mem = dev_get_coherent_memory(dev); - - if (!mem) - return 0; - - *ret = __dma_alloc_from_coherent(mem, size, dma_handle); - if (*ret) - return 1; - - /* - * In the case where the allocation can not be satisfied from the - * per-device area, try to fall back to generic memory if the - * constraints allow it. - */ - return mem->flags & DMA_MEMORY_EXCLUSIVE; -} -EXPORT_SYMBOL(dma_alloc_from_dev_coherent); - -void *dma_alloc_from_global_coherent(ssize_t size, dma_addr_t *dma_handle) -{ - if (!dma_coherent_default_memory) - return NULL; - - return __dma_alloc_from_coherent(dma_coherent_default_memory, size, - dma_handle); -} - -static int __dma_release_from_coherent(struct dma_coherent_mem *mem, - int order, void *vaddr) -{ - if (mem && vaddr >= mem->virt_base && vaddr < - (mem->virt_base + (mem->size << PAGE_SHIFT))) { - int page = (vaddr - mem->virt_base) >> PAGE_SHIFT; - unsigned long flags; - - spin_lock_irqsave(&mem->spinlock, flags); - bitmap_release_region(mem->bitmap, page, order); - spin_unlock_irqrestore(&mem->spinlock, flags); - return 1; - } - return 0; -} - -/** - * dma_release_from_dev_coherent() - free memory to device coherent memory pool - * @dev: device from which the memory was allocated - * @order: the order of pages allocated - * @vaddr: virtual address of allocated pages - * - * This checks whether the memory was allocated from the per-device - * coherent memory pool and if so, releases that memory. - * - * Returns 1 if we correctly released the memory, or 0 if the caller should - * proceed with releasing memory from generic pools. - */ -int dma_release_from_dev_coherent(struct device *dev, int order, void *vaddr) -{ - struct dma_coherent_mem *mem = dev_get_coherent_memory(dev); - - return __dma_release_from_coherent(mem, order, vaddr); -} -EXPORT_SYMBOL(dma_release_from_dev_coherent); - -int dma_release_from_global_coherent(int order, void *vaddr) -{ - if (!dma_coherent_default_memory) - return 0; - - return __dma_release_from_coherent(dma_coherent_default_memory, order, - vaddr); -} - -static int __dma_mmap_from_coherent(struct dma_coherent_mem *mem, - struct vm_area_struct *vma, void *vaddr, size_t size, int *ret) -{ - if (mem && vaddr >= mem->virt_base && vaddr + size <= - (mem->virt_base + (mem->size << PAGE_SHIFT))) { - unsigned long off = vma->vm_pgoff; - int start = (vaddr - mem->virt_base) >> PAGE_SHIFT; - int user_count = vma_pages(vma); - int count = PAGE_ALIGN(size) >> PAGE_SHIFT; - - *ret = -ENXIO; - if (off < count && user_count <= count - off) { - unsigned long pfn = mem->pfn_base + start + off; - *ret = remap_pfn_range(vma, vma->vm_start, pfn, - user_count << PAGE_SHIFT, - vma->vm_page_prot); - } - return 1; - } - return 0; -} - -/** - * dma_mmap_from_dev_coherent() - mmap memory from the device coherent pool - * @dev: device from which the memory was allocated - * @vma: vm_area for the userspace memory - * @vaddr: cpu address returned by dma_alloc_from_dev_coherent - * @size: size of the memory buffer allocated - * @ret: result from remap_pfn_range() - * - * This checks whether the memory was allocated from the per-device - * coherent memory pool and if so, maps that memory to the provided vma. - * - * Returns 1 if @vaddr belongs to the device coherent pool and the caller - * should return @ret, or 0 if they should proceed with mapping memory from - * generic areas. - */ -int dma_mmap_from_dev_coherent(struct device *dev, struct vm_area_struct *vma, - void *vaddr, size_t size, int *ret) -{ - struct dma_coherent_mem *mem = dev_get_coherent_memory(dev); - - return __dma_mmap_from_coherent(mem, vma, vaddr, size, ret); -} -EXPORT_SYMBOL(dma_mmap_from_dev_coherent); - -int dma_mmap_from_global_coherent(struct vm_area_struct *vma, void *vaddr, - size_t size, int *ret) -{ - if (!dma_coherent_default_memory) - return 0; - - return __dma_mmap_from_coherent(dma_coherent_default_memory, vma, - vaddr, size, ret); -} - -/* - * Support for reserved memory regions defined in device tree - */ -#ifdef CONFIG_OF_RESERVED_MEM -#include -#include -#include - -static struct reserved_mem *dma_reserved_default_memory __initdata; - -static int rmem_dma_device_init(struct reserved_mem *rmem, struct device *dev) -{ - struct dma_coherent_mem *mem = rmem->priv; - int ret; - - if (!mem) { - ret = dma_init_coherent_memory(rmem->base, rmem->base, - rmem->size, - DMA_MEMORY_EXCLUSIVE, &mem); - if (ret) { - pr_err("Reserved memory: failed to init DMA memory pool at %pa, size %ld MiB\n", - &rmem->base, (unsigned long)rmem->size / SZ_1M); - return ret; - } - } - mem->use_dev_dma_pfn_offset = true; - rmem->priv = mem; - dma_assign_coherent_memory(dev, mem); - return 0; -} - -static void rmem_dma_device_release(struct reserved_mem *rmem, - struct device *dev) -{ - if (dev) - dev->dma_mem = NULL; -} - -static const struct reserved_mem_ops rmem_dma_ops = { - .device_init = rmem_dma_device_init, - .device_release = rmem_dma_device_release, -}; - -static int __init rmem_dma_setup(struct reserved_mem *rmem) -{ - unsigned long node = rmem->fdt_node; - - if (of_get_flat_dt_prop(node, "reusable", NULL)) - return -EINVAL; - -#ifdef CONFIG_ARM - if (!of_get_flat_dt_prop(node, "no-map", NULL)) { - pr_err("Reserved memory: regions without no-map are not yet supported\n"); - return -EINVAL; - } - - if (of_get_flat_dt_prop(node, "linux,dma-default", NULL)) { - WARN(dma_reserved_default_memory, - "Reserved memory: region for default DMA coherent area is redefined\n"); - dma_reserved_default_memory = rmem; - } -#endif - - rmem->ops = &rmem_dma_ops; - pr_info("Reserved memory: created DMA memory pool at %pa, size %ld MiB\n", - &rmem->base, (unsigned long)rmem->size / SZ_1M); - return 0; -} - -static int __init dma_init_reserved_memory(void) -{ - const struct reserved_mem_ops *ops; - int ret; - - if (!dma_reserved_default_memory) - return -ENOMEM; - - ops = dma_reserved_default_memory->ops; - - /* - * We rely on rmem_dma_device_init() does not propagate error of - * dma_assign_coherent_memory() for "NULL" device. - */ - ret = ops->device_init(dma_reserved_default_memory, NULL); - - if (!ret) { - dma_coherent_default_memory = dma_reserved_default_memory->priv; - pr_info("DMA: default coherent area is set\n"); - } - - return ret; -} - -core_initcall(dma_init_reserved_memory); - -RESERVEDMEM_OF_DECLARE(dma, "shared-dma-pool", rmem_dma_setup); -#endif diff --git a/drivers/base/dma-contiguous.c b/drivers/base/dma-contiguous.c deleted file mode 100644 index d987dcd1bd56..000000000000 --- a/drivers/base/dma-contiguous.c +++ /dev/null @@ -1,278 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0+ -/* - * Contiguous Memory Allocator for DMA mapping framework - * Copyright (c) 2010-2011 by Samsung Electronics. - * Written by: - * Marek Szyprowski - * Michal Nazarewicz - */ - -#define pr_fmt(fmt) "cma: " fmt - -#ifdef CONFIG_CMA_DEBUG -#ifndef DEBUG -# define DEBUG -#endif -#endif - -#include -#include - -#include -#include -#include -#include -#include - -#ifdef CONFIG_CMA_SIZE_MBYTES -#define CMA_SIZE_MBYTES CONFIG_CMA_SIZE_MBYTES -#else -#define CMA_SIZE_MBYTES 0 -#endif - -struct cma *dma_contiguous_default_area; - -/* - * Default global CMA area size can be defined in kernel's .config. - * This is useful mainly for distro maintainers to create a kernel - * that works correctly for most supported systems. - * The size can be set in bytes or as a percentage of the total memory - * in the system. - * - * Users, who want to set the size of global CMA area for their system - * should use cma= kernel parameter. - */ -static const phys_addr_t size_bytes = (phys_addr_t)CMA_SIZE_MBYTES * SZ_1M; -static phys_addr_t size_cmdline = -1; -static phys_addr_t base_cmdline; -static phys_addr_t limit_cmdline; - -static int __init early_cma(char *p) -{ - pr_debug("%s(%s)\n", __func__, p); - size_cmdline = memparse(p, &p); - if (*p != '@') - return 0; - base_cmdline = memparse(p + 1, &p); - if (*p != '-') { - limit_cmdline = base_cmdline + size_cmdline; - return 0; - } - limit_cmdline = memparse(p + 1, &p); - - return 0; -} -early_param("cma", early_cma); - -#ifdef CONFIG_CMA_SIZE_PERCENTAGE - -static phys_addr_t __init __maybe_unused cma_early_percent_memory(void) -{ - struct memblock_region *reg; - unsigned long total_pages = 0; - - /* - * We cannot use memblock_phys_mem_size() here, because - * memblock_analyze() has not been called yet. - */ - for_each_memblock(memory, reg) - total_pages += memblock_region_memory_end_pfn(reg) - - memblock_region_memory_base_pfn(reg); - - return (total_pages * CONFIG_CMA_SIZE_PERCENTAGE / 100) << PAGE_SHIFT; -} - -#else - -static inline __maybe_unused phys_addr_t cma_early_percent_memory(void) -{ - return 0; -} - -#endif - -/** - * dma_contiguous_reserve() - reserve area(s) for contiguous memory handling - * @limit: End address of the reserved memory (optional, 0 for any). - * - * This function reserves memory from early allocator. It should be - * called by arch specific code once the early allocator (memblock or bootmem) - * has been activated and all other subsystems have already allocated/reserved - * memory. - */ -void __init dma_contiguous_reserve(phys_addr_t limit) -{ - phys_addr_t selected_size = 0; - phys_addr_t selected_base = 0; - phys_addr_t selected_limit = limit; - bool fixed = false; - - pr_debug("%s(limit %08lx)\n", __func__, (unsigned long)limit); - - if (size_cmdline != -1) { - selected_size = size_cmdline; - selected_base = base_cmdline; - selected_limit = min_not_zero(limit_cmdline, limit); - if (base_cmdline + size_cmdline == limit_cmdline) - fixed = true; - } else { -#ifdef CONFIG_CMA_SIZE_SEL_MBYTES - selected_size = size_bytes; -#elif defined(CONFIG_CMA_SIZE_SEL_PERCENTAGE) - selected_size = cma_early_percent_memory(); -#elif defined(CONFIG_CMA_SIZE_SEL_MIN) - selected_size = min(size_bytes, cma_early_percent_memory()); -#elif defined(CONFIG_CMA_SIZE_SEL_MAX) - selected_size = max(size_bytes, cma_early_percent_memory()); -#endif - } - - if (selected_size && !dma_contiguous_default_area) { - pr_debug("%s: reserving %ld MiB for global area\n", __func__, - (unsigned long)selected_size / SZ_1M); - - dma_contiguous_reserve_area(selected_size, selected_base, - selected_limit, - &dma_contiguous_default_area, - fixed); - } -} - -/** - * dma_contiguous_reserve_area() - reserve custom contiguous area - * @size: Size of the reserved area (in bytes), - * @base: Base address of the reserved area optional, use 0 for any - * @limit: End address of the reserved memory (optional, 0 for any). - * @res_cma: Pointer to store the created cma region. - * @fixed: hint about where to place the reserved area - * - * This function reserves memory from early allocator. It should be - * called by arch specific code once the early allocator (memblock or bootmem) - * has been activated and all other subsystems have already allocated/reserved - * memory. This function allows to create custom reserved areas for specific - * devices. - * - * If @fixed is true, reserve contiguous area at exactly @base. If false, - * reserve in range from @base to @limit. - */ -int __init dma_contiguous_reserve_area(phys_addr_t size, phys_addr_t base, - phys_addr_t limit, struct cma **res_cma, - bool fixed) -{ - int ret; - - ret = cma_declare_contiguous(base, size, limit, 0, 0, fixed, - "reserved", res_cma); - if (ret) - return ret; - - /* Architecture specific contiguous memory fixup. */ - dma_contiguous_early_fixup(cma_get_base(*res_cma), - cma_get_size(*res_cma)); - - return 0; -} - -/** - * dma_alloc_from_contiguous() - allocate pages from contiguous area - * @dev: Pointer to device for which the allocation is performed. - * @count: Requested number of pages. - * @align: Requested alignment of pages (in PAGE_SIZE order). - * @gfp_mask: GFP flags to use for this allocation. - * - * This function allocates memory buffer for specified device. It uses - * device specific contiguous memory area if available or the default - * global one. Requires architecture specific dev_get_cma_area() helper - * function. - */ -struct page *dma_alloc_from_contiguous(struct device *dev, size_t count, - unsigned int align, gfp_t gfp_mask) -{ - if (align > CONFIG_CMA_ALIGNMENT) - align = CONFIG_CMA_ALIGNMENT; - - return cma_alloc(dev_get_cma_area(dev), count, align, gfp_mask); -} - -/** - * dma_release_from_contiguous() - release allocated pages - * @dev: Pointer to device for which the pages were allocated. - * @pages: Allocated pages. - * @count: Number of allocated pages. - * - * This function releases memory allocated by dma_alloc_from_contiguous(). - * It returns false when provided pages do not belong to contiguous area and - * true otherwise. - */ -bool dma_release_from_contiguous(struct device *dev, struct page *pages, - int count) -{ - return cma_release(dev_get_cma_area(dev), pages, count); -} - -/* - * Support for reserved memory regions defined in device tree - */ -#ifdef CONFIG_OF_RESERVED_MEM -#include -#include -#include - -#undef pr_fmt -#define pr_fmt(fmt) fmt - -static int rmem_cma_device_init(struct reserved_mem *rmem, struct device *dev) -{ - dev_set_cma_area(dev, rmem->priv); - return 0; -} - -static void rmem_cma_device_release(struct reserved_mem *rmem, - struct device *dev) -{ - dev_set_cma_area(dev, NULL); -} - -static const struct reserved_mem_ops rmem_cma_ops = { - .device_init = rmem_cma_device_init, - .device_release = rmem_cma_device_release, -}; - -static int __init rmem_cma_setup(struct reserved_mem *rmem) -{ - phys_addr_t align = PAGE_SIZE << max(MAX_ORDER - 1, pageblock_order); - phys_addr_t mask = align - 1; - unsigned long node = rmem->fdt_node; - struct cma *cma; - int err; - - if (!of_get_flat_dt_prop(node, "reusable", NULL) || - of_get_flat_dt_prop(node, "no-map", NULL)) - return -EINVAL; - - if ((rmem->base & mask) || (rmem->size & mask)) { - pr_err("Reserved memory: incorrect alignment of CMA region\n"); - return -EINVAL; - } - - err = cma_init_reserved_mem(rmem->base, rmem->size, 0, rmem->name, &cma); - if (err) { - pr_err("Reserved memory: unable to setup CMA region\n"); - return err; - } - /* Architecture specific contiguous memory fixup. */ - dma_contiguous_early_fixup(rmem->base, rmem->size); - - if (of_get_flat_dt_prop(node, "linux,cma-default", NULL)) - dma_contiguous_set_default(cma); - - rmem->ops = &rmem_cma_ops; - rmem->priv = cma; - - pr_info("Reserved memory: created CMA memory pool at %pa, size %ld MiB\n", - &rmem->base, (unsigned long)rmem->size / SZ_1M); - - return 0; -} -RESERVEDMEM_OF_DECLARE(cma, "shared-dma-pool", rmem_cma_setup); -#endif diff --git a/drivers/base/dma-mapping.c b/drivers/base/dma-mapping.c deleted file mode 100644 index f831a582209c..000000000000 --- a/drivers/base/dma-mapping.c +++ /dev/null @@ -1,345 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 -/* - * drivers/base/dma-mapping.c - arch-independent dma-mapping routines - * - * Copyright (c) 2006 SUSE Linux Products GmbH - * Copyright (c) 2006 Tejun Heo - */ - -#include -#include -#include -#include -#include -#include -#include - -/* - * Managed DMA API - */ -struct dma_devres { - size_t size; - void *vaddr; - dma_addr_t dma_handle; - unsigned long attrs; -}; - -static void dmam_release(struct device *dev, void *res) -{ - struct dma_devres *this = res; - - dma_free_attrs(dev, this->size, this->vaddr, this->dma_handle, - this->attrs); -} - -static int dmam_match(struct device *dev, void *res, void *match_data) -{ - struct dma_devres *this = res, *match = match_data; - - if (this->vaddr == match->vaddr) { - WARN_ON(this->size != match->size || - this->dma_handle != match->dma_handle); - return 1; - } - return 0; -} - -/** - * dmam_alloc_coherent - Managed dma_alloc_coherent() - * @dev: Device to allocate coherent memory for - * @size: Size of allocation - * @dma_handle: Out argument for allocated DMA handle - * @gfp: Allocation flags - * - * Managed dma_alloc_coherent(). Memory allocated using this function - * will be automatically released on driver detach. - * - * RETURNS: - * Pointer to allocated memory on success, NULL on failure. - */ -void *dmam_alloc_coherent(struct device *dev, size_t size, - dma_addr_t *dma_handle, gfp_t gfp) -{ - struct dma_devres *dr; - void *vaddr; - - dr = devres_alloc(dmam_release, sizeof(*dr), gfp); - if (!dr) - return NULL; - - vaddr = dma_alloc_coherent(dev, size, dma_handle, gfp); - if (!vaddr) { - devres_free(dr); - return NULL; - } - - dr->vaddr = vaddr; - dr->dma_handle = *dma_handle; - dr->size = size; - - devres_add(dev, dr); - - return vaddr; -} -EXPORT_SYMBOL(dmam_alloc_coherent); - -/** - * dmam_free_coherent - Managed dma_free_coherent() - * @dev: Device to free coherent memory for - * @size: Size of allocation - * @vaddr: Virtual address of the memory to free - * @dma_handle: DMA handle of the memory to free - * - * Managed dma_free_coherent(). - */ -void dmam_free_coherent(struct device *dev, size_t size, void *vaddr, - dma_addr_t dma_handle) -{ - struct dma_devres match_data = { size, vaddr, dma_handle }; - - dma_free_coherent(dev, size, vaddr, dma_handle); - WARN_ON(devres_destroy(dev, dmam_release, dmam_match, &match_data)); -} -EXPORT_SYMBOL(dmam_free_coherent); - -/** - * dmam_alloc_attrs - Managed dma_alloc_attrs() - * @dev: Device to allocate non_coherent memory for - * @size: Size of allocation - * @dma_handle: Out argument for allocated DMA handle - * @gfp: Allocation flags - * @attrs: Flags in the DMA_ATTR_* namespace. - * - * Managed dma_alloc_attrs(). Memory allocated using this function will be - * automatically released on driver detach. - * - * RETURNS: - * Pointer to allocated memory on success, NULL on failure. - */ -void *dmam_alloc_attrs(struct device *dev, size_t size, dma_addr_t *dma_handle, - gfp_t gfp, unsigned long attrs) -{ - struct dma_devres *dr; - void *vaddr; - - dr = devres_alloc(dmam_release, sizeof(*dr), gfp); - if (!dr) - return NULL; - - vaddr = dma_alloc_attrs(dev, size, dma_handle, gfp, attrs); - if (!vaddr) { - devres_free(dr); - return NULL; - } - - dr->vaddr = vaddr; - dr->dma_handle = *dma_handle; - dr->size = size; - dr->attrs = attrs; - - devres_add(dev, dr); - - return vaddr; -} -EXPORT_SYMBOL(dmam_alloc_attrs); - -#ifdef CONFIG_HAVE_GENERIC_DMA_COHERENT - -static void dmam_coherent_decl_release(struct device *dev, void *res) -{ - dma_release_declared_memory(dev); -} - -/** - * dmam_declare_coherent_memory - Managed dma_declare_coherent_memory() - * @dev: Device to declare coherent memory for - * @phys_addr: Physical address of coherent memory to be declared - * @device_addr: Device address of coherent memory to be declared - * @size: Size of coherent memory to be declared - * @flags: Flags - * - * Managed dma_declare_coherent_memory(). - * - * RETURNS: - * 0 on success, -errno on failure. - */ -int dmam_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr, - dma_addr_t device_addr, size_t size, int flags) -{ - void *res; - int rc; - - res = devres_alloc(dmam_coherent_decl_release, 0, GFP_KERNEL); - if (!res) - return -ENOMEM; - - rc = dma_declare_coherent_memory(dev, phys_addr, device_addr, size, - flags); - if (!rc) - devres_add(dev, res); - else - devres_free(res); - - return rc; -} -EXPORT_SYMBOL(dmam_declare_coherent_memory); - -/** - * dmam_release_declared_memory - Managed dma_release_declared_memory(). - * @dev: Device to release declared coherent memory for - * - * Managed dmam_release_declared_memory(). - */ -void dmam_release_declared_memory(struct device *dev) -{ - WARN_ON(devres_destroy(dev, dmam_coherent_decl_release, NULL, NULL)); -} -EXPORT_SYMBOL(dmam_release_declared_memory); - -#endif - -/* - * Create scatter-list for the already allocated DMA buffer. - */ -int dma_common_get_sgtable(struct device *dev, struct sg_table *sgt, - void *cpu_addr, dma_addr_t handle, size_t size) -{ - struct page *page = virt_to_page(cpu_addr); - int ret; - - ret = sg_alloc_table(sgt, 1, GFP_KERNEL); - if (unlikely(ret)) - return ret; - - sg_set_page(sgt->sgl, page, PAGE_ALIGN(size), 0); - return 0; -} -EXPORT_SYMBOL(dma_common_get_sgtable); - -/* - * Create userspace mapping for the DMA-coherent memory. - */ -int dma_common_mmap(struct device *dev, struct vm_area_struct *vma, - void *cpu_addr, dma_addr_t dma_addr, size_t size) -{ - int ret = -ENXIO; -#ifndef CONFIG_ARCH_NO_COHERENT_DMA_MMAP - unsigned long user_count = vma_pages(vma); - unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT; - unsigned long off = vma->vm_pgoff; - - vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); - - if (dma_mmap_from_dev_coherent(dev, vma, cpu_addr, size, &ret)) - return ret; - - if (off < count && user_count <= (count - off)) - ret = remap_pfn_range(vma, vma->vm_start, - page_to_pfn(virt_to_page(cpu_addr)) + off, - user_count << PAGE_SHIFT, - vma->vm_page_prot); -#endif /* !CONFIG_ARCH_NO_COHERENT_DMA_MMAP */ - - return ret; -} -EXPORT_SYMBOL(dma_common_mmap); - -#ifdef CONFIG_MMU -static struct vm_struct *__dma_common_pages_remap(struct page **pages, - size_t size, unsigned long vm_flags, pgprot_t prot, - const void *caller) -{ - struct vm_struct *area; - - area = get_vm_area_caller(size, vm_flags, caller); - if (!area) - return NULL; - - if (map_vm_area(area, prot, pages)) { - vunmap(area->addr); - return NULL; - } - - return area; -} - -/* - * remaps an array of PAGE_SIZE pages into another vm_area - * Cannot be used in non-sleeping contexts - */ -void *dma_common_pages_remap(struct page **pages, size_t size, - unsigned long vm_flags, pgprot_t prot, - const void *caller) -{ - struct vm_struct *area; - - area = __dma_common_pages_remap(pages, size, vm_flags, prot, caller); - if (!area) - return NULL; - - area->pages = pages; - - return area->addr; -} - -/* - * remaps an allocated contiguous region into another vm_area. - * Cannot be used in non-sleeping contexts - */ - -void *dma_common_contiguous_remap(struct page *page, size_t size, - unsigned long vm_flags, - pgprot_t prot, const void *caller) -{ - int i; - struct page **pages; - struct vm_struct *area; - - pages = kmalloc(sizeof(struct page *) << get_order(size), GFP_KERNEL); - if (!pages) - return NULL; - - for (i = 0; i < (size >> PAGE_SHIFT); i++) - pages[i] = nth_page(page, i); - - area = __dma_common_pages_remap(pages, size, vm_flags, prot, caller); - - kfree(pages); - - if (!area) - return NULL; - return area->addr; -} - -/* - * unmaps a range previously mapped by dma_common_*_remap - */ -void dma_common_free_remap(void *cpu_addr, size_t size, unsigned long vm_flags) -{ - struct vm_struct *area = find_vm_area(cpu_addr); - - if (!area || (area->flags & vm_flags) != vm_flags) { - WARN(1, "trying to free invalid coherent area: %p\n", cpu_addr); - return; - } - - unmap_kernel_range((unsigned long)cpu_addr, PAGE_ALIGN(size)); - vunmap(cpu_addr); -} -#endif - -/* - * enables DMA API use for a device - */ -int dma_configure(struct device *dev) -{ - if (dev->bus->dma_configure) - return dev->bus->dma_configure(dev); - return 0; -} - -void dma_deconfigure(struct device *dev) -{ - of_dma_deconfigure(dev); - acpi_dma_deconfigure(dev); -} diff --git a/include/linux/dma-contiguous.h b/include/linux/dma-contiguous.h index b67bf6ac907d..3c5a4cb3eb95 100644 --- a/include/linux/dma-contiguous.h +++ b/include/linux/dma-contiguous.h @@ -48,7 +48,7 @@ * CMA should not be used by the device drivers directly. It is * only a helper framework for dma-mapping subsystem. * - * For more information, see kernel-docs in drivers/base/dma-contiguous.c + * For more information, see kernel-docs in kernel/dma/contiguous.c */ #ifdef __KERNEL__ diff --git a/init/Kconfig b/init/Kconfig index 5a52f07259a2..fde3d09e8b27 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -1719,10 +1719,6 @@ source "arch/Kconfig" endmenu # General setup -config HAVE_GENERIC_DMA_COHERENT - bool - default n - config RT_MUTEXES bool diff --git a/kernel/Makefile b/kernel/Makefile index d2001624fe7a..04bc07c2b42a 100644 --- a/kernel/Makefile +++ b/kernel/Makefile @@ -41,6 +41,7 @@ obj-y += printk/ obj-y += irq/ obj-y += rcu/ obj-y += livepatch/ +obj-y += dma/ obj-$(CONFIG_CHECKPOINT_RESTORE) += kcmp.o obj-$(CONFIG_FREEZER) += freezer.o diff --git a/kernel/dma/Kconfig b/kernel/dma/Kconfig new file mode 100644 index 000000000000..9bd54304446f --- /dev/null +++ b/kernel/dma/Kconfig @@ -0,0 +1,50 @@ + +config HAS_DMA + bool + depends on !NO_DMA + default y + +config NEED_SG_DMA_LENGTH + bool + +config NEED_DMA_MAP_STATE + bool + +config ARCH_DMA_ADDR_T_64BIT + def_bool 64BIT || PHYS_ADDR_T_64BIT + +config HAVE_GENERIC_DMA_COHERENT + bool + +config ARCH_HAS_SYNC_DMA_FOR_DEVICE + bool + +config ARCH_HAS_SYNC_DMA_FOR_CPU + bool + select NEED_DMA_MAP_STATE + +config DMA_DIRECT_OPS + bool + depends on HAS_DMA + +config DMA_NONCOHERENT_OPS + bool + depends on HAS_DMA + select DMA_DIRECT_OPS + +config DMA_NONCOHERENT_MMAP + bool + depends on DMA_NONCOHERENT_OPS + +config DMA_NONCOHERENT_CACHE_SYNC + bool + depends on DMA_NONCOHERENT_OPS + +config DMA_VIRT_OPS + bool + depends on HAS_DMA + +config SWIOTLB + bool + select DMA_DIRECT_OPS + select NEED_DMA_MAP_STATE diff --git a/kernel/dma/Makefile b/kernel/dma/Makefile new file mode 100644 index 000000000000..6de44e4eb454 --- /dev/null +++ b/kernel/dma/Makefile @@ -0,0 +1,11 @@ +# SPDX-License-Identifier: GPL-2.0 + +obj-$(CONFIG_HAS_DMA) += mapping.o +obj-$(CONFIG_DMA_CMA) += contiguous.o +obj-$(CONFIG_HAVE_GENERIC_DMA_COHERENT) += coherent.o +obj-$(CONFIG_DMA_DIRECT_OPS) += direct.o +obj-$(CONFIG_DMA_NONCOHERENT_OPS) += noncoherent.o +obj-$(CONFIG_DMA_VIRT_OPS) += virt.o +obj-$(CONFIG_DMA_API_DEBUG) += debug.o +obj-$(CONFIG_SWIOTLB) += swiotlb.o + diff --git a/kernel/dma/coherent.c b/kernel/dma/coherent.c new file mode 100644 index 000000000000..597d40893862 --- /dev/null +++ b/kernel/dma/coherent.c @@ -0,0 +1,434 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Coherent per-device memory handling. + * Borrowed from i386 + */ +#include +#include +#include +#include +#include + +struct dma_coherent_mem { + void *virt_base; + dma_addr_t device_base; + unsigned long pfn_base; + int size; + int flags; + unsigned long *bitmap; + spinlock_t spinlock; + bool use_dev_dma_pfn_offset; +}; + +static struct dma_coherent_mem *dma_coherent_default_memory __ro_after_init; + +static inline struct dma_coherent_mem *dev_get_coherent_memory(struct device *dev) +{ + if (dev && dev->dma_mem) + return dev->dma_mem; + return NULL; +} + +static inline dma_addr_t dma_get_device_base(struct device *dev, + struct dma_coherent_mem * mem) +{ + if (mem->use_dev_dma_pfn_offset) + return (mem->pfn_base - dev->dma_pfn_offset) << PAGE_SHIFT; + else + return mem->device_base; +} + +static int dma_init_coherent_memory( + phys_addr_t phys_addr, dma_addr_t device_addr, size_t size, int flags, + struct dma_coherent_mem **mem) +{ + struct dma_coherent_mem *dma_mem = NULL; + void __iomem *mem_base = NULL; + int pages = size >> PAGE_SHIFT; + int bitmap_size = BITS_TO_LONGS(pages) * sizeof(long); + int ret; + + if (!size) { + ret = -EINVAL; + goto out; + } + + mem_base = memremap(phys_addr, size, MEMREMAP_WC); + if (!mem_base) { + ret = -EINVAL; + goto out; + } + dma_mem = kzalloc(sizeof(struct dma_coherent_mem), GFP_KERNEL); + if (!dma_mem) { + ret = -ENOMEM; + goto out; + } + dma_mem->bitmap = kzalloc(bitmap_size, GFP_KERNEL); + if (!dma_mem->bitmap) { + ret = -ENOMEM; + goto out; + } + + dma_mem->virt_base = mem_base; + dma_mem->device_base = device_addr; + dma_mem->pfn_base = PFN_DOWN(phys_addr); + dma_mem->size = pages; + dma_mem->flags = flags; + spin_lock_init(&dma_mem->spinlock); + + *mem = dma_mem; + return 0; + +out: + kfree(dma_mem); + if (mem_base) + memunmap(mem_base); + return ret; +} + +static void dma_release_coherent_memory(struct dma_coherent_mem *mem) +{ + if (!mem) + return; + + memunmap(mem->virt_base); + kfree(mem->bitmap); + kfree(mem); +} + +static int dma_assign_coherent_memory(struct device *dev, + struct dma_coherent_mem *mem) +{ + if (!dev) + return -ENODEV; + + if (dev->dma_mem) + return -EBUSY; + + dev->dma_mem = mem; + return 0; +} + +int dma_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr, + dma_addr_t device_addr, size_t size, int flags) +{ + struct dma_coherent_mem *mem; + int ret; + + ret = dma_init_coherent_memory(phys_addr, device_addr, size, flags, &mem); + if (ret) + return ret; + + ret = dma_assign_coherent_memory(dev, mem); + if (ret) + dma_release_coherent_memory(mem); + return ret; +} +EXPORT_SYMBOL(dma_declare_coherent_memory); + +void dma_release_declared_memory(struct device *dev) +{ + struct dma_coherent_mem *mem = dev->dma_mem; + + if (!mem) + return; + dma_release_coherent_memory(mem); + dev->dma_mem = NULL; +} +EXPORT_SYMBOL(dma_release_declared_memory); + +void *dma_mark_declared_memory_occupied(struct device *dev, + dma_addr_t device_addr, size_t size) +{ + struct dma_coherent_mem *mem = dev->dma_mem; + unsigned long flags; + int pos, err; + + size += device_addr & ~PAGE_MASK; + + if (!mem) + return ERR_PTR(-EINVAL); + + spin_lock_irqsave(&mem->spinlock, flags); + pos = PFN_DOWN(device_addr - dma_get_device_base(dev, mem)); + err = bitmap_allocate_region(mem->bitmap, pos, get_order(size)); + spin_unlock_irqrestore(&mem->spinlock, flags); + + if (err != 0) + return ERR_PTR(err); + return mem->virt_base + (pos << PAGE_SHIFT); +} +EXPORT_SYMBOL(dma_mark_declared_memory_occupied); + +static void *__dma_alloc_from_coherent(struct dma_coherent_mem *mem, + ssize_t size, dma_addr_t *dma_handle) +{ + int order = get_order(size); + unsigned long flags; + int pageno; + void *ret; + + spin_lock_irqsave(&mem->spinlock, flags); + + if (unlikely(size > (mem->size << PAGE_SHIFT))) + goto err; + + pageno = bitmap_find_free_region(mem->bitmap, mem->size, order); + if (unlikely(pageno < 0)) + goto err; + + /* + * Memory was found in the coherent area. + */ + *dma_handle = mem->device_base + (pageno << PAGE_SHIFT); + ret = mem->virt_base + (pageno << PAGE_SHIFT); + spin_unlock_irqrestore(&mem->spinlock, flags); + memset(ret, 0, size); + return ret; +err: + spin_unlock_irqrestore(&mem->spinlock, flags); + return NULL; +} + +/** + * dma_alloc_from_dev_coherent() - allocate memory from device coherent pool + * @dev: device from which we allocate memory + * @size: size of requested memory area + * @dma_handle: This will be filled with the correct dma handle + * @ret: This pointer will be filled with the virtual address + * to allocated area. + * + * This function should be only called from per-arch dma_alloc_coherent() + * to support allocation from per-device coherent memory pools. + * + * Returns 0 if dma_alloc_coherent should continue with allocating from + * generic memory areas, or !0 if dma_alloc_coherent should return @ret. + */ +int dma_alloc_from_dev_coherent(struct device *dev, ssize_t size, + dma_addr_t *dma_handle, void **ret) +{ + struct dma_coherent_mem *mem = dev_get_coherent_memory(dev); + + if (!mem) + return 0; + + *ret = __dma_alloc_from_coherent(mem, size, dma_handle); + if (*ret) + return 1; + + /* + * In the case where the allocation can not be satisfied from the + * per-device area, try to fall back to generic memory if the + * constraints allow it. + */ + return mem->flags & DMA_MEMORY_EXCLUSIVE; +} +EXPORT_SYMBOL(dma_alloc_from_dev_coherent); + +void *dma_alloc_from_global_coherent(ssize_t size, dma_addr_t *dma_handle) +{ + if (!dma_coherent_default_memory) + return NULL; + + return __dma_alloc_from_coherent(dma_coherent_default_memory, size, + dma_handle); +} + +static int __dma_release_from_coherent(struct dma_coherent_mem *mem, + int order, void *vaddr) +{ + if (mem && vaddr >= mem->virt_base && vaddr < + (mem->virt_base + (mem->size << PAGE_SHIFT))) { + int page = (vaddr - mem->virt_base) >> PAGE_SHIFT; + unsigned long flags; + + spin_lock_irqsave(&mem->spinlock, flags); + bitmap_release_region(mem->bitmap, page, order); + spin_unlock_irqrestore(&mem->spinlock, flags); + return 1; + } + return 0; +} + +/** + * dma_release_from_dev_coherent() - free memory to device coherent memory pool + * @dev: device from which the memory was allocated + * @order: the order of pages allocated + * @vaddr: virtual address of allocated pages + * + * This checks whether the memory was allocated from the per-device + * coherent memory pool and if so, releases that memory. + * + * Returns 1 if we correctly released the memory, or 0 if the caller should + * proceed with releasing memory from generic pools. + */ +int dma_release_from_dev_coherent(struct device *dev, int order, void *vaddr) +{ + struct dma_coherent_mem *mem = dev_get_coherent_memory(dev); + + return __dma_release_from_coherent(mem, order, vaddr); +} +EXPORT_SYMBOL(dma_release_from_dev_coherent); + +int dma_release_from_global_coherent(int order, void *vaddr) +{ + if (!dma_coherent_default_memory) + return 0; + + return __dma_release_from_coherent(dma_coherent_default_memory, order, + vaddr); +} + +static int __dma_mmap_from_coherent(struct dma_coherent_mem *mem, + struct vm_area_struct *vma, void *vaddr, size_t size, int *ret) +{ + if (mem && vaddr >= mem->virt_base && vaddr + size <= + (mem->virt_base + (mem->size << PAGE_SHIFT))) { + unsigned long off = vma->vm_pgoff; + int start = (vaddr - mem->virt_base) >> PAGE_SHIFT; + int user_count = vma_pages(vma); + int count = PAGE_ALIGN(size) >> PAGE_SHIFT; + + *ret = -ENXIO; + if (off < count && user_count <= count - off) { + unsigned long pfn = mem->pfn_base + start + off; + *ret = remap_pfn_range(vma, vma->vm_start, pfn, + user_count << PAGE_SHIFT, + vma->vm_page_prot); + } + return 1; + } + return 0; +} + +/** + * dma_mmap_from_dev_coherent() - mmap memory from the device coherent pool + * @dev: device from which the memory was allocated + * @vma: vm_area for the userspace memory + * @vaddr: cpu address returned by dma_alloc_from_dev_coherent + * @size: size of the memory buffer allocated + * @ret: result from remap_pfn_range() + * + * This checks whether the memory was allocated from the per-device + * coherent memory pool and if so, maps that memory to the provided vma. + * + * Returns 1 if @vaddr belongs to the device coherent pool and the caller + * should return @ret, or 0 if they should proceed with mapping memory from + * generic areas. + */ +int dma_mmap_from_dev_coherent(struct device *dev, struct vm_area_struct *vma, + void *vaddr, size_t size, int *ret) +{ + struct dma_coherent_mem *mem = dev_get_coherent_memory(dev); + + return __dma_mmap_from_coherent(mem, vma, vaddr, size, ret); +} +EXPORT_SYMBOL(dma_mmap_from_dev_coherent); + +int dma_mmap_from_global_coherent(struct vm_area_struct *vma, void *vaddr, + size_t size, int *ret) +{ + if (!dma_coherent_default_memory) + return 0; + + return __dma_mmap_from_coherent(dma_coherent_default_memory, vma, + vaddr, size, ret); +} + +/* + * Support for reserved memory regions defined in device tree + */ +#ifdef CONFIG_OF_RESERVED_MEM +#include +#include +#include + +static struct reserved_mem *dma_reserved_default_memory __initdata; + +static int rmem_dma_device_init(struct reserved_mem *rmem, struct device *dev) +{ + struct dma_coherent_mem *mem = rmem->priv; + int ret; + + if (!mem) { + ret = dma_init_coherent_memory(rmem->base, rmem->base, + rmem->size, + DMA_MEMORY_EXCLUSIVE, &mem); + if (ret) { + pr_err("Reserved memory: failed to init DMA memory pool at %pa, size %ld MiB\n", + &rmem->base, (unsigned long)rmem->size / SZ_1M); + return ret; + } + } + mem->use_dev_dma_pfn_offset = true; + rmem->priv = mem; + dma_assign_coherent_memory(dev, mem); + return 0; +} + +static void rmem_dma_device_release(struct reserved_mem *rmem, + struct device *dev) +{ + if (dev) + dev->dma_mem = NULL; +} + +static const struct reserved_mem_ops rmem_dma_ops = { + .device_init = rmem_dma_device_init, + .device_release = rmem_dma_device_release, +}; + +static int __init rmem_dma_setup(struct reserved_mem *rmem) +{ + unsigned long node = rmem->fdt_node; + + if (of_get_flat_dt_prop(node, "reusable", NULL)) + return -EINVAL; + +#ifdef CONFIG_ARM + if (!of_get_flat_dt_prop(node, "no-map", NULL)) { + pr_err("Reserved memory: regions without no-map are not yet supported\n"); + return -EINVAL; + } + + if (of_get_flat_dt_prop(node, "linux,dma-default", NULL)) { + WARN(dma_reserved_default_memory, + "Reserved memory: region for default DMA coherent area is redefined\n"); + dma_reserved_default_memory = rmem; + } +#endif + + rmem->ops = &rmem_dma_ops; + pr_info("Reserved memory: created DMA memory pool at %pa, size %ld MiB\n", + &rmem->base, (unsigned long)rmem->size / SZ_1M); + return 0; +} + +static int __init dma_init_reserved_memory(void) +{ + const struct reserved_mem_ops *ops; + int ret; + + if (!dma_reserved_default_memory) + return -ENOMEM; + + ops = dma_reserved_default_memory->ops; + + /* + * We rely on rmem_dma_device_init() does not propagate error of + * dma_assign_coherent_memory() for "NULL" device. + */ + ret = ops->device_init(dma_reserved_default_memory, NULL); + + if (!ret) { + dma_coherent_default_memory = dma_reserved_default_memory->priv; + pr_info("DMA: default coherent area is set\n"); + } + + return ret; +} + +core_initcall(dma_init_reserved_memory); + +RESERVEDMEM_OF_DECLARE(dma, "shared-dma-pool", rmem_dma_setup); +#endif diff --git a/kernel/dma/contiguous.c b/kernel/dma/contiguous.c new file mode 100644 index 000000000000..d987dcd1bd56 --- /dev/null +++ b/kernel/dma/contiguous.c @@ -0,0 +1,278 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Contiguous Memory Allocator for DMA mapping framework + * Copyright (c) 2010-2011 by Samsung Electronics. + * Written by: + * Marek Szyprowski + * Michal Nazarewicz + */ + +#define pr_fmt(fmt) "cma: " fmt + +#ifdef CONFIG_CMA_DEBUG +#ifndef DEBUG +# define DEBUG +#endif +#endif + +#include +#include + +#include +#include +#include +#include +#include + +#ifdef CONFIG_CMA_SIZE_MBYTES +#define CMA_SIZE_MBYTES CONFIG_CMA_SIZE_MBYTES +#else +#define CMA_SIZE_MBYTES 0 +#endif + +struct cma *dma_contiguous_default_area; + +/* + * Default global CMA area size can be defined in kernel's .config. + * This is useful mainly for distro maintainers to create a kernel + * that works correctly for most supported systems. + * The size can be set in bytes or as a percentage of the total memory + * in the system. + * + * Users, who want to set the size of global CMA area for their system + * should use cma= kernel parameter. + */ +static const phys_addr_t size_bytes = (phys_addr_t)CMA_SIZE_MBYTES * SZ_1M; +static phys_addr_t size_cmdline = -1; +static phys_addr_t base_cmdline; +static phys_addr_t limit_cmdline; + +static int __init early_cma(char *p) +{ + pr_debug("%s(%s)\n", __func__, p); + size_cmdline = memparse(p, &p); + if (*p != '@') + return 0; + base_cmdline = memparse(p + 1, &p); + if (*p != '-') { + limit_cmdline = base_cmdline + size_cmdline; + return 0; + } + limit_cmdline = memparse(p + 1, &p); + + return 0; +} +early_param("cma", early_cma); + +#ifdef CONFIG_CMA_SIZE_PERCENTAGE + +static phys_addr_t __init __maybe_unused cma_early_percent_memory(void) +{ + struct memblock_region *reg; + unsigned long total_pages = 0; + + /* + * We cannot use memblock_phys_mem_size() here, because + * memblock_analyze() has not been called yet. + */ + for_each_memblock(memory, reg) + total_pages += memblock_region_memory_end_pfn(reg) - + memblock_region_memory_base_pfn(reg); + + return (total_pages * CONFIG_CMA_SIZE_PERCENTAGE / 100) << PAGE_SHIFT; +} + +#else + +static inline __maybe_unused phys_addr_t cma_early_percent_memory(void) +{ + return 0; +} + +#endif + +/** + * dma_contiguous_reserve() - reserve area(s) for contiguous memory handling + * @limit: End address of the reserved memory (optional, 0 for any). + * + * This function reserves memory from early allocator. It should be + * called by arch specific code once the early allocator (memblock or bootmem) + * has been activated and all other subsystems have already allocated/reserved + * memory. + */ +void __init dma_contiguous_reserve(phys_addr_t limit) +{ + phys_addr_t selected_size = 0; + phys_addr_t selected_base = 0; + phys_addr_t selected_limit = limit; + bool fixed = false; + + pr_debug("%s(limit %08lx)\n", __func__, (unsigned long)limit); + + if (size_cmdline != -1) { + selected_size = size_cmdline; + selected_base = base_cmdline; + selected_limit = min_not_zero(limit_cmdline, limit); + if (base_cmdline + size_cmdline == limit_cmdline) + fixed = true; + } else { +#ifdef CONFIG_CMA_SIZE_SEL_MBYTES + selected_size = size_bytes; +#elif defined(CONFIG_CMA_SIZE_SEL_PERCENTAGE) + selected_size = cma_early_percent_memory(); +#elif defined(CONFIG_CMA_SIZE_SEL_MIN) + selected_size = min(size_bytes, cma_early_percent_memory()); +#elif defined(CONFIG_CMA_SIZE_SEL_MAX) + selected_size = max(size_bytes, cma_early_percent_memory()); +#endif + } + + if (selected_size && !dma_contiguous_default_area) { + pr_debug("%s: reserving %ld MiB for global area\n", __func__, + (unsigned long)selected_size / SZ_1M); + + dma_contiguous_reserve_area(selected_size, selected_base, + selected_limit, + &dma_contiguous_default_area, + fixed); + } +} + +/** + * dma_contiguous_reserve_area() - reserve custom contiguous area + * @size: Size of the reserved area (in bytes), + * @base: Base address of the reserved area optional, use 0 for any + * @limit: End address of the reserved memory (optional, 0 for any). + * @res_cma: Pointer to store the created cma region. + * @fixed: hint about where to place the reserved area + * + * This function reserves memory from early allocator. It should be + * called by arch specific code once the early allocator (memblock or bootmem) + * has been activated and all other subsystems have already allocated/reserved + * memory. This function allows to create custom reserved areas for specific + * devices. + * + * If @fixed is true, reserve contiguous area at exactly @base. If false, + * reserve in range from @base to @limit. + */ +int __init dma_contiguous_reserve_area(phys_addr_t size, phys_addr_t base, + phys_addr_t limit, struct cma **res_cma, + bool fixed) +{ + int ret; + + ret = cma_declare_contiguous(base, size, limit, 0, 0, fixed, + "reserved", res_cma); + if (ret) + return ret; + + /* Architecture specific contiguous memory fixup. */ + dma_contiguous_early_fixup(cma_get_base(*res_cma), + cma_get_size(*res_cma)); + + return 0; +} + +/** + * dma_alloc_from_contiguous() - allocate pages from contiguous area + * @dev: Pointer to device for which the allocation is performed. + * @count: Requested number of pages. + * @align: Requested alignment of pages (in PAGE_SIZE order). + * @gfp_mask: GFP flags to use for this allocation. + * + * This function allocates memory buffer for specified device. It uses + * device specific contiguous memory area if available or the default + * global one. Requires architecture specific dev_get_cma_area() helper + * function. + */ +struct page *dma_alloc_from_contiguous(struct device *dev, size_t count, + unsigned int align, gfp_t gfp_mask) +{ + if (align > CONFIG_CMA_ALIGNMENT) + align = CONFIG_CMA_ALIGNMENT; + + return cma_alloc(dev_get_cma_area(dev), count, align, gfp_mask); +} + +/** + * dma_release_from_contiguous() - release allocated pages + * @dev: Pointer to device for which the pages were allocated. + * @pages: Allocated pages. + * @count: Number of allocated pages. + * + * This function releases memory allocated by dma_alloc_from_contiguous(). + * It returns false when provided pages do not belong to contiguous area and + * true otherwise. + */ +bool dma_release_from_contiguous(struct device *dev, struct page *pages, + int count) +{ + return cma_release(dev_get_cma_area(dev), pages, count); +} + +/* + * Support for reserved memory regions defined in device tree + */ +#ifdef CONFIG_OF_RESERVED_MEM +#include +#include +#include + +#undef pr_fmt +#define pr_fmt(fmt) fmt + +static int rmem_cma_device_init(struct reserved_mem *rmem, struct device *dev) +{ + dev_set_cma_area(dev, rmem->priv); + return 0; +} + +static void rmem_cma_device_release(struct reserved_mem *rmem, + struct device *dev) +{ + dev_set_cma_area(dev, NULL); +} + +static const struct reserved_mem_ops rmem_cma_ops = { + .device_init = rmem_cma_device_init, + .device_release = rmem_cma_device_release, +}; + +static int __init rmem_cma_setup(struct reserved_mem *rmem) +{ + phys_addr_t align = PAGE_SIZE << max(MAX_ORDER - 1, pageblock_order); + phys_addr_t mask = align - 1; + unsigned long node = rmem->fdt_node; + struct cma *cma; + int err; + + if (!of_get_flat_dt_prop(node, "reusable", NULL) || + of_get_flat_dt_prop(node, "no-map", NULL)) + return -EINVAL; + + if ((rmem->base & mask) || (rmem->size & mask)) { + pr_err("Reserved memory: incorrect alignment of CMA region\n"); + return -EINVAL; + } + + err = cma_init_reserved_mem(rmem->base, rmem->size, 0, rmem->name, &cma); + if (err) { + pr_err("Reserved memory: unable to setup CMA region\n"); + return err; + } + /* Architecture specific contiguous memory fixup. */ + dma_contiguous_early_fixup(rmem->base, rmem->size); + + if (of_get_flat_dt_prop(node, "linux,cma-default", NULL)) + dma_contiguous_set_default(cma); + + rmem->ops = &rmem_cma_ops; + rmem->priv = cma; + + pr_info("Reserved memory: created CMA memory pool at %pa, size %ld MiB\n", + &rmem->base, (unsigned long)rmem->size / SZ_1M); + + return 0; +} +RESERVEDMEM_OF_DECLARE(cma, "shared-dma-pool", rmem_cma_setup); +#endif diff --git a/kernel/dma/debug.c b/kernel/dma/debug.c new file mode 100644 index 000000000000..c007d25bee09 --- /dev/null +++ b/kernel/dma/debug.c @@ -0,0 +1,1773 @@ +/* + * Copyright (C) 2008 Advanced Micro Devices, Inc. + * + * Author: Joerg Roedel + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published + * by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include + +#define HASH_SIZE 1024ULL +#define HASH_FN_SHIFT 13 +#define HASH_FN_MASK (HASH_SIZE - 1) + +/* allow architectures to override this if absolutely required */ +#ifndef PREALLOC_DMA_DEBUG_ENTRIES +#define PREALLOC_DMA_DEBUG_ENTRIES (1 << 16) +#endif + +enum { + dma_debug_single, + dma_debug_page, + dma_debug_sg, + dma_debug_coherent, + dma_debug_resource, +}; + +enum map_err_types { + MAP_ERR_CHECK_NOT_APPLICABLE, + MAP_ERR_NOT_CHECKED, + MAP_ERR_CHECKED, +}; + +#define DMA_DEBUG_STACKTRACE_ENTRIES 5 + +/** + * struct dma_debug_entry - track a dma_map* or dma_alloc_coherent mapping + * @list: node on pre-allocated free_entries list + * @dev: 'dev' argument to dma_map_{page|single|sg} or dma_alloc_coherent + * @type: single, page, sg, coherent + * @pfn: page frame of the start address + * @offset: offset of mapping relative to pfn + * @size: length of the mapping + * @direction: enum dma_data_direction + * @sg_call_ents: 'nents' from dma_map_sg + * @sg_mapped_ents: 'mapped_ents' from dma_map_sg + * @map_err_type: track whether dma_mapping_error() was checked + * @stacktrace: support backtraces when a violation is detected + */ +struct dma_debug_entry { + struct list_head list; + struct device *dev; + int type; + unsigned long pfn; + size_t offset; + u64 dev_addr; + u64 size; + int direction; + int sg_call_ents; + int sg_mapped_ents; + enum map_err_types map_err_type; +#ifdef CONFIG_STACKTRACE + struct stack_trace stacktrace; + unsigned long st_entries[DMA_DEBUG_STACKTRACE_ENTRIES]; +#endif +}; + +typedef bool (*match_fn)(struct dma_debug_entry *, struct dma_debug_entry *); + +struct hash_bucket { + struct list_head list; + spinlock_t lock; +} ____cacheline_aligned_in_smp; + +/* Hash list to save the allocated dma addresses */ +static struct hash_bucket dma_entry_hash[HASH_SIZE]; +/* List of pre-allocated dma_debug_entry's */ +static LIST_HEAD(free_entries); +/* Lock for the list above */ +static DEFINE_SPINLOCK(free_entries_lock); + +/* Global disable flag - will be set in case of an error */ +static bool global_disable __read_mostly; + +/* Early initialization disable flag, set at the end of dma_debug_init */ +static bool dma_debug_initialized __read_mostly; + +static inline bool dma_debug_disabled(void) +{ + return global_disable || !dma_debug_initialized; +} + +/* Global error count */ +static u32 error_count; + +/* Global error show enable*/ +static u32 show_all_errors __read_mostly; +/* Number of errors to show */ +static u32 show_num_errors = 1; + +static u32 num_free_entries; +static u32 min_free_entries; +static u32 nr_total_entries; + +/* number of preallocated entries requested by kernel cmdline */ +static u32 nr_prealloc_entries = PREALLOC_DMA_DEBUG_ENTRIES; + +/* debugfs dentry's for the stuff above */ +static struct dentry *dma_debug_dent __read_mostly; +static struct dentry *global_disable_dent __read_mostly; +static struct dentry *error_count_dent __read_mostly; +static struct dentry *show_all_errors_dent __read_mostly; +static struct dentry *show_num_errors_dent __read_mostly; +static struct dentry *num_free_entries_dent __read_mostly; +static struct dentry *min_free_entries_dent __read_mostly; +static struct dentry *filter_dent __read_mostly; + +/* per-driver filter related state */ + +#define NAME_MAX_LEN 64 + +static char current_driver_name[NAME_MAX_LEN] __read_mostly; +static struct device_driver *current_driver __read_mostly; + +static DEFINE_RWLOCK(driver_name_lock); + +static const char *const maperr2str[] = { + [MAP_ERR_CHECK_NOT_APPLICABLE] = "dma map error check not applicable", + [MAP_ERR_NOT_CHECKED] = "dma map error not checked", + [MAP_ERR_CHECKED] = "dma map error checked", +}; + +static const char *type2name[5] = { "single", "page", + "scather-gather", "coherent", + "resource" }; + +static const char *dir2name[4] = { "DMA_BIDIRECTIONAL", "DMA_TO_DEVICE", + "DMA_FROM_DEVICE", "DMA_NONE" }; + +/* + * The access to some variables in this macro is racy. We can't use atomic_t + * here because all these variables are exported to debugfs. Some of them even + * writeable. This is also the reason why a lock won't help much. But anyway, + * the races are no big deal. Here is why: + * + * error_count: the addition is racy, but the worst thing that can happen is + * that we don't count some errors + * show_num_errors: the subtraction is racy. Also no big deal because in + * worst case this will result in one warning more in the + * system log than the user configured. This variable is + * writeable via debugfs. + */ +static inline void dump_entry_trace(struct dma_debug_entry *entry) +{ +#ifdef CONFIG_STACKTRACE + if (entry) { + pr_warning("Mapped at:\n"); + print_stack_trace(&entry->stacktrace, 0); + } +#endif +} + +static bool driver_filter(struct device *dev) +{ + struct device_driver *drv; + unsigned long flags; + bool ret; + + /* driver filter off */ + if (likely(!current_driver_name[0])) + return true; + + /* driver filter on and initialized */ + if (current_driver && dev && dev->driver == current_driver) + return true; + + /* driver filter on, but we can't filter on a NULL device... */ + if (!dev) + return false; + + if (current_driver || !current_driver_name[0]) + return false; + + /* driver filter on but not yet initialized */ + drv = dev->driver; + if (!drv) + return false; + + /* lock to protect against change of current_driver_name */ + read_lock_irqsave(&driver_name_lock, flags); + + ret = false; + if (drv->name && + strncmp(current_driver_name, drv->name, NAME_MAX_LEN - 1) == 0) { + current_driver = drv; + ret = true; + } + + read_unlock_irqrestore(&driver_name_lock, flags); + + return ret; +} + +#define err_printk(dev, entry, format, arg...) do { \ + error_count += 1; \ + if (driver_filter(dev) && \ + (show_all_errors || show_num_errors > 0)) { \ + WARN(1, "%s %s: " format, \ + dev ? dev_driver_string(dev) : "NULL", \ + dev ? dev_name(dev) : "NULL", ## arg); \ + dump_entry_trace(entry); \ + } \ + if (!show_all_errors && show_num_errors > 0) \ + show_num_errors -= 1; \ + } while (0); + +/* + * Hash related functions + * + * Every DMA-API request is saved into a struct dma_debug_entry. To + * have quick access to these structs they are stored into a hash. + */ +static int hash_fn(struct dma_debug_entry *entry) +{ + /* + * Hash function is based on the dma address. + * We use bits 20-27 here as the index into the hash + */ + return (entry->dev_addr >> HASH_FN_SHIFT) & HASH_FN_MASK; +} + +/* + * Request exclusive access to a hash bucket for a given dma_debug_entry. + */ +static struct hash_bucket *get_hash_bucket(struct dma_debug_entry *entry, + unsigned long *flags) + __acquires(&dma_entry_hash[idx].lock) +{ + int idx = hash_fn(entry); + unsigned long __flags; + + spin_lock_irqsave(&dma_entry_hash[idx].lock, __flags); + *flags = __flags; + return &dma_entry_hash[idx]; +} + +/* + * Give up exclusive access to the hash bucket + */ +static void put_hash_bucket(struct hash_bucket *bucket, + unsigned long *flags) + __releases(&bucket->lock) +{ + unsigned long __flags = *flags; + + spin_unlock_irqrestore(&bucket->lock, __flags); +} + +static bool exact_match(struct dma_debug_entry *a, struct dma_debug_entry *b) +{ + return ((a->dev_addr == b->dev_addr) && + (a->dev == b->dev)) ? true : false; +} + +static bool containing_match(struct dma_debug_entry *a, + struct dma_debug_entry *b) +{ + if (a->dev != b->dev) + return false; + + if ((b->dev_addr <= a->dev_addr) && + ((b->dev_addr + b->size) >= (a->dev_addr + a->size))) + return true; + + return false; +} + +/* + * Search a given entry in the hash bucket list + */ +static struct dma_debug_entry *__hash_bucket_find(struct hash_bucket *bucket, + struct dma_debug_entry *ref, + match_fn match) +{ + struct dma_debug_entry *entry, *ret = NULL; + int matches = 0, match_lvl, last_lvl = -1; + + list_for_each_entry(entry, &bucket->list, list) { + if (!match(ref, entry)) + continue; + + /* + * Some drivers map the same physical address multiple + * times. Without a hardware IOMMU this results in the + * same device addresses being put into the dma-debug + * hash multiple times too. This can result in false + * positives being reported. Therefore we implement a + * best-fit algorithm here which returns the entry from + * the hash which fits best to the reference value + * instead of the first-fit. + */ + matches += 1; + match_lvl = 0; + entry->size == ref->size ? ++match_lvl : 0; + entry->type == ref->type ? ++match_lvl : 0; + entry->direction == ref->direction ? ++match_lvl : 0; + entry->sg_call_ents == ref->sg_call_ents ? ++match_lvl : 0; + + if (match_lvl == 4) { + /* perfect-fit - return the result */ + return entry; + } else if (match_lvl > last_lvl) { + /* + * We found an entry that fits better then the + * previous one or it is the 1st match. + */ + last_lvl = match_lvl; + ret = entry; + } + } + + /* + * If we have multiple matches but no perfect-fit, just return + * NULL. + */ + ret = (matches == 1) ? ret : NULL; + + return ret; +} + +static struct dma_debug_entry *bucket_find_exact(struct hash_bucket *bucket, + struct dma_debug_entry *ref) +{ + return __hash_bucket_find(bucket, ref, exact_match); +} + +static struct dma_debug_entry *bucket_find_contain(struct hash_bucket **bucket, + struct dma_debug_entry *ref, + unsigned long *flags) +{ + + unsigned int max_range = dma_get_max_seg_size(ref->dev); + struct dma_debug_entry *entry, index = *ref; + unsigned int range = 0; + + while (range <= max_range) { + entry = __hash_bucket_find(*bucket, ref, containing_match); + + if (entry) + return entry; + + /* + * Nothing found, go back a hash bucket + */ + put_hash_bucket(*bucket, flags); + range += (1 << HASH_FN_SHIFT); + index.dev_addr -= (1 << HASH_FN_SHIFT); + *bucket = get_hash_bucket(&index, flags); + } + + return NULL; +} + +/* + * Add an entry to a hash bucket + */ +static void hash_bucket_add(struct hash_bucket *bucket, + struct dma_debug_entry *entry) +{ + list_add_tail(&entry->list, &bucket->list); +} + +/* + * Remove entry from a hash bucket list + */ +static void hash_bucket_del(struct dma_debug_entry *entry) +{ + list_del(&entry->list); +} + +static unsigned long long phys_addr(struct dma_debug_entry *entry) +{ + if (entry->type == dma_debug_resource) + return __pfn_to_phys(entry->pfn) + entry->offset; + + return page_to_phys(pfn_to_page(entry->pfn)) + entry->offset; +} + +/* + * Dump mapping entries for debugging purposes + */ +void debug_dma_dump_mappings(struct device *dev) +{ + int idx; + + for (idx = 0; idx < HASH_SIZE; idx++) { + struct hash_bucket *bucket = &dma_entry_hash[idx]; + struct dma_debug_entry *entry; + unsigned long flags; + + spin_lock_irqsave(&bucket->lock, flags); + + list_for_each_entry(entry, &bucket->list, list) { + if (!dev || dev == entry->dev) { + dev_info(entry->dev, + "%s idx %d P=%Lx N=%lx D=%Lx L=%Lx %s %s\n", + type2name[entry->type], idx, + phys_addr(entry), entry->pfn, + entry->dev_addr, entry->size, + dir2name[entry->direction], + maperr2str[entry->map_err_type]); + } + } + + spin_unlock_irqrestore(&bucket->lock, flags); + } +} + +/* + * For each mapping (initial cacheline in the case of + * dma_alloc_coherent/dma_map_page, initial cacheline in each page of a + * scatterlist, or the cacheline specified in dma_map_single) insert + * into this tree using the cacheline as the key. At + * dma_unmap_{single|sg|page} or dma_free_coherent delete the entry. If + * the entry already exists at insertion time add a tag as a reference + * count for the overlapping mappings. For now, the overlap tracking + * just ensures that 'unmaps' balance 'maps' before marking the + * cacheline idle, but we should also be flagging overlaps as an API + * violation. + * + * Memory usage is mostly constrained by the maximum number of available + * dma-debug entries in that we need a free dma_debug_entry before + * inserting into the tree. In the case of dma_map_page and + * dma_alloc_coherent there is only one dma_debug_entry and one + * dma_active_cacheline entry to track per event. dma_map_sg(), on the + * other hand, consumes a single dma_debug_entry, but inserts 'nents' + * entries into the tree. + * + * At any time debug_dma_assert_idle() can be called to trigger a + * warning if any cachelines in the given page are in the active set. + */ +static RADIX_TREE(dma_active_cacheline, GFP_NOWAIT); +static DEFINE_SPINLOCK(radix_lock); +#define ACTIVE_CACHELINE_MAX_OVERLAP ((1 << RADIX_TREE_MAX_TAGS) - 1) +#define CACHELINE_PER_PAGE_SHIFT (PAGE_SHIFT - L1_CACHE_SHIFT) +#define CACHELINES_PER_PAGE (1 << CACHELINE_PER_PAGE_SHIFT) + +static phys_addr_t to_cacheline_number(struct dma_debug_entry *entry) +{ + return (entry->pfn << CACHELINE_PER_PAGE_SHIFT) + + (entry->offset >> L1_CACHE_SHIFT); +} + +static int active_cacheline_read_overlap(phys_addr_t cln) +{ + int overlap = 0, i; + + for (i = RADIX_TREE_MAX_TAGS - 1; i >= 0; i--) + if (radix_tree_tag_get(&dma_active_cacheline, cln, i)) + overlap |= 1 << i; + return overlap; +} + +static int active_cacheline_set_overlap(phys_addr_t cln, int overlap) +{ + int i; + + if (overlap > ACTIVE_CACHELINE_MAX_OVERLAP || overlap < 0) + return overlap; + + for (i = RADIX_TREE_MAX_TAGS - 1; i >= 0; i--) + if (overlap & 1 << i) + radix_tree_tag_set(&dma_active_cacheline, cln, i); + else + radix_tree_tag_clear(&dma_active_cacheline, cln, i); + + return overlap; +} + +static void active_cacheline_inc_overlap(phys_addr_t cln) +{ + int overlap = active_cacheline_read_overlap(cln); + + overlap = active_cacheline_set_overlap(cln, ++overlap); + + /* If we overflowed the overlap counter then we're potentially + * leaking dma-mappings. Otherwise, if maps and unmaps are + * balanced then this overflow may cause false negatives in + * debug_dma_assert_idle() as the cacheline may be marked idle + * prematurely. + */ + WARN_ONCE(overlap > ACTIVE_CACHELINE_MAX_OVERLAP, + "DMA-API: exceeded %d overlapping mappings of cacheline %pa\n", + ACTIVE_CACHELINE_MAX_OVERLAP, &cln); +} + +static int active_cacheline_dec_overlap(phys_addr_t cln) +{ + int overlap = active_cacheline_read_overlap(cln); + + return active_cacheline_set_overlap(cln, --overlap); +} + +static int active_cacheline_insert(struct dma_debug_entry *entry) +{ + phys_addr_t cln = to_cacheline_number(entry); + unsigned long flags; + int rc; + + /* If the device is not writing memory then we don't have any + * concerns about the cpu consuming stale data. This mitigates + * legitimate usages of overlapping mappings. + */ + if (entry->direction == DMA_TO_DEVICE) + return 0; + + spin_lock_irqsave(&radix_lock, flags); + rc = radix_tree_insert(&dma_active_cacheline, cln, entry); + if (rc == -EEXIST) + active_cacheline_inc_overlap(cln); + spin_unlock_irqrestore(&radix_lock, flags); + + return rc; +} + +static void active_cacheline_remove(struct dma_debug_entry *entry) +{ + phys_addr_t cln = to_cacheline_number(entry); + unsigned long flags; + + /* ...mirror the insert case */ + if (entry->direction == DMA_TO_DEVICE) + return; + + spin_lock_irqsave(&radix_lock, flags); + /* since we are counting overlaps the final put of the + * cacheline will occur when the overlap count is 0. + * active_cacheline_dec_overlap() returns -1 in that case + */ + if (active_cacheline_dec_overlap(cln) < 0) + radix_tree_delete(&dma_active_cacheline, cln); + spin_unlock_irqrestore(&radix_lock, flags); +} + +/** + * debug_dma_assert_idle() - assert that a page is not undergoing dma + * @page: page to lookup in the dma_active_cacheline tree + * + * Place a call to this routine in cases where the cpu touching the page + * before the dma completes (page is dma_unmapped) will lead to data + * corruption. + */ +void debug_dma_assert_idle(struct page *page) +{ + static struct dma_debug_entry *ents[CACHELINES_PER_PAGE]; + struct dma_debug_entry *entry = NULL; + void **results = (void **) &ents; + unsigned int nents, i; + unsigned long flags; + phys_addr_t cln; + + if (dma_debug_disabled()) + return; + + if (!page) + return; + + cln = (phys_addr_t) page_to_pfn(page) << CACHELINE_PER_PAGE_SHIFT; + spin_lock_irqsave(&radix_lock, flags); + nents = radix_tree_gang_lookup(&dma_active_cacheline, results, cln, + CACHELINES_PER_PAGE); + for (i = 0; i < nents; i++) { + phys_addr_t ent_cln = to_cacheline_number(ents[i]); + + if (ent_cln == cln) { + entry = ents[i]; + break; + } else if (ent_cln >= cln + CACHELINES_PER_PAGE) + break; + } + spin_unlock_irqrestore(&radix_lock, flags); + + if (!entry) + return; + + cln = to_cacheline_number(entry); + err_printk(entry->dev, entry, + "DMA-API: cpu touching an active dma mapped cacheline [cln=%pa]\n", + &cln); +} + +/* + * Wrapper function for adding an entry to the hash. + * This function takes care of locking itself. + */ +static void add_dma_entry(struct dma_debug_entry *entry) +{ + struct hash_bucket *bucket; + unsigned long flags; + int rc; + + bucket = get_hash_bucket(entry, &flags); + hash_bucket_add(bucket, entry); + put_hash_bucket(bucket, &flags); + + rc = active_cacheline_insert(entry); + if (rc == -ENOMEM) { + pr_err("DMA-API: cacheline tracking ENOMEM, dma-debug disabled\n"); + global_disable = true; + } + + /* TODO: report -EEXIST errors here as overlapping mappings are + * not supported by the DMA API + */ +} + +static struct dma_debug_entry *__dma_entry_alloc(void) +{ + struct dma_debug_entry *entry; + + entry = list_entry(free_entries.next, struct dma_debug_entry, list); + list_del(&entry->list); + memset(entry, 0, sizeof(*entry)); + + num_free_entries -= 1; + if (num_free_entries < min_free_entries) + min_free_entries = num_free_entries; + + return entry; +} + +/* struct dma_entry allocator + * + * The next two functions implement the allocator for + * struct dma_debug_entries. + */ +static struct dma_debug_entry *dma_entry_alloc(void) +{ + struct dma_debug_entry *entry; + unsigned long flags; + + spin_lock_irqsave(&free_entries_lock, flags); + + if (list_empty(&free_entries)) { + global_disable = true; + spin_unlock_irqrestore(&free_entries_lock, flags); + pr_err("DMA-API: debugging out of memory - disabling\n"); + return NULL; + } + + entry = __dma_entry_alloc(); + + spin_unlock_irqrestore(&free_entries_lock, flags); + +#ifdef CONFIG_STACKTRACE + entry->stacktrace.max_entries = DMA_DEBUG_STACKTRACE_ENTRIES; + entry->stacktrace.entries = entry->st_entries; + entry->stacktrace.skip = 2; + save_stack_trace(&entry->stacktrace); +#endif + + return entry; +} + +static void dma_entry_free(struct dma_debug_entry *entry) +{ + unsigned long flags; + + active_cacheline_remove(entry); + + /* + * add to beginning of the list - this way the entries are + * more likely cache hot when they are reallocated. + */ + spin_lock_irqsave(&free_entries_lock, flags); + list_add(&entry->list, &free_entries); + num_free_entries += 1; + spin_unlock_irqrestore(&free_entries_lock, flags); +} + +int dma_debug_resize_entries(u32 num_entries) +{ + int i, delta, ret = 0; + unsigned long flags; + struct dma_debug_entry *entry; + LIST_HEAD(tmp); + + spin_lock_irqsave(&free_entries_lock, flags); + + if (nr_total_entries < num_entries) { + delta = num_entries - nr_total_entries; + + spin_unlock_irqrestore(&free_entries_lock, flags); + + for (i = 0; i < delta; i++) { + entry = kzalloc(sizeof(*entry), GFP_KERNEL); + if (!entry) + break; + + list_add_tail(&entry->list, &tmp); + } + + spin_lock_irqsave(&free_entries_lock, flags); + + list_splice(&tmp, &free_entries); + nr_total_entries += i; + num_free_entries += i; + } else { + delta = nr_total_entries - num_entries; + + for (i = 0; i < delta && !list_empty(&free_entries); i++) { + entry = __dma_entry_alloc(); + kfree(entry); + } + + nr_total_entries -= i; + } + + if (nr_total_entries != num_entries) + ret = 1; + + spin_unlock_irqrestore(&free_entries_lock, flags); + + return ret; +} + +/* + * DMA-API debugging init code + * + * The init code does two things: + * 1. Initialize core data structures + * 2. Preallocate a given number of dma_debug_entry structs + */ + +static int prealloc_memory(u32 num_entries) +{ + struct dma_debug_entry *entry, *next_entry; + int i; + + for (i = 0; i < num_entries; ++i) { + entry = kzalloc(sizeof(*entry), GFP_KERNEL); + if (!entry) + goto out_err; + + list_add_tail(&entry->list, &free_entries); + } + + num_free_entries = num_entries; + min_free_entries = num_entries; + + pr_info("DMA-API: preallocated %d debug entries\n", num_entries); + + return 0; + +out_err: + + list_for_each_entry_safe(entry, next_entry, &free_entries, list) { + list_del(&entry->list); + kfree(entry); + } + + return -ENOMEM; +} + +static ssize_t filter_read(struct file *file, char __user *user_buf, + size_t count, loff_t *ppos) +{ + char buf[NAME_MAX_LEN + 1]; + unsigned long flags; + int len; + + if (!current_driver_name[0]) + return 0; + + /* + * We can't copy to userspace directly because current_driver_name can + * only be read under the driver_name_lock with irqs disabled. So + * create a temporary copy first. + */ + read_lock_irqsave(&driver_name_lock, flags); + len = scnprintf(buf, NAME_MAX_LEN + 1, "%s\n", current_driver_name); + read_unlock_irqrestore(&driver_name_lock, flags); + + return simple_read_from_buffer(user_buf, count, ppos, buf, len); +} + +static ssize_t filter_write(struct file *file, const char __user *userbuf, + size_t count, loff_t *ppos) +{ + char buf[NAME_MAX_LEN]; + unsigned long flags; + size_t len; + int i; + + /* + * We can't copy from userspace directly. Access to + * current_driver_name is protected with a write_lock with irqs + * disabled. Since copy_from_user can fault and may sleep we + * need to copy to temporary buffer first + */ + len = min(count, (size_t)(NAME_MAX_LEN - 1)); + if (copy_from_user(buf, userbuf, len)) + return -EFAULT; + + buf[len] = 0; + + write_lock_irqsave(&driver_name_lock, flags); + + /* + * Now handle the string we got from userspace very carefully. + * The rules are: + * - only use the first token we got + * - token delimiter is everything looking like a space + * character (' ', '\n', '\t' ...) + * + */ + if (!isalnum(buf[0])) { + /* + * If the first character userspace gave us is not + * alphanumerical then assume the filter should be + * switched off. + */ + if (current_driver_name[0]) + pr_info("DMA-API: switching off dma-debug driver filter\n"); + current_driver_name[0] = 0; + current_driver = NULL; + goto out_unlock; + } + + /* + * Now parse out the first token and use it as the name for the + * driver to filter for. + */ + for (i = 0; i < NAME_MAX_LEN - 1; ++i) { + current_driver_name[i] = buf[i]; + if (isspace(buf[i]) || buf[i] == ' ' || buf[i] == 0) + break; + } + current_driver_name[i] = 0; + current_driver = NULL; + + pr_info("DMA-API: enable driver filter for driver [%s]\n", + current_driver_name); + +out_unlock: + write_unlock_irqrestore(&driver_name_lock, flags); + + return count; +} + +static const struct file_operations filter_fops = { + .read = filter_read, + .write = filter_write, + .llseek = default_llseek, +}; + +static int dma_debug_fs_init(void) +{ + dma_debug_dent = debugfs_create_dir("dma-api", NULL); + if (!dma_debug_dent) { + pr_err("DMA-API: can not create debugfs directory\n"); + return -ENOMEM; + } + + global_disable_dent = debugfs_create_bool("disabled", 0444, + dma_debug_dent, + &global_disable); + if (!global_disable_dent) + goto out_err; + + error_count_dent = debugfs_create_u32("error_count", 0444, + dma_debug_dent, &error_count); + if (!error_count_dent) + goto out_err; + + show_all_errors_dent = debugfs_create_u32("all_errors", 0644, + dma_debug_dent, + &show_all_errors); + if (!show_all_errors_dent) + goto out_err; + + show_num_errors_dent = debugfs_create_u32("num_errors", 0644, + dma_debug_dent, + &show_num_errors); + if (!show_num_errors_dent) + goto out_err; + + num_free_entries_dent = debugfs_create_u32("num_free_entries", 0444, + dma_debug_dent, + &num_free_entries); + if (!num_free_entries_dent) + goto out_err; + + min_free_entries_dent = debugfs_create_u32("min_free_entries", 0444, + dma_debug_dent, + &min_free_entries); + if (!min_free_entries_dent) + goto out_err; + + filter_dent = debugfs_create_file("driver_filter", 0644, + dma_debug_dent, NULL, &filter_fops); + if (!filter_dent) + goto out_err; + + return 0; + +out_err: + debugfs_remove_recursive(dma_debug_dent); + + return -ENOMEM; +} + +static int device_dma_allocations(struct device *dev, struct dma_debug_entry **out_entry) +{ + struct dma_debug_entry *entry; + unsigned long flags; + int count = 0, i; + + for (i = 0; i < HASH_SIZE; ++i) { + spin_lock_irqsave(&dma_entry_hash[i].lock, flags); + list_for_each_entry(entry, &dma_entry_hash[i].list, list) { + if (entry->dev == dev) { + count += 1; + *out_entry = entry; + } + } + spin_unlock_irqrestore(&dma_entry_hash[i].lock, flags); + } + + return count; +} + +static int dma_debug_device_change(struct notifier_block *nb, unsigned long action, void *data) +{ + struct device *dev = data; + struct dma_debug_entry *uninitialized_var(entry); + int count; + + if (dma_debug_disabled()) + return 0; + + switch (action) { + case BUS_NOTIFY_UNBOUND_DRIVER: + count = device_dma_allocations(dev, &entry); + if (count == 0) + break; + err_printk(dev, entry, "DMA-API: device driver has pending " + "DMA allocations while released from device " + "[count=%d]\n" + "One of leaked entries details: " + "[device address=0x%016llx] [size=%llu bytes] " + "[mapped with %s] [mapped as %s]\n", + count, entry->dev_addr, entry->size, + dir2name[entry->direction], type2name[entry->type]); + break; + default: + break; + } + + return 0; +} + +void dma_debug_add_bus(struct bus_type *bus) +{ + struct notifier_block *nb; + + if (dma_debug_disabled()) + return; + + nb = kzalloc(sizeof(struct notifier_block), GFP_KERNEL); + if (nb == NULL) { + pr_err("dma_debug_add_bus: out of memory\n"); + return; + } + + nb->notifier_call = dma_debug_device_change; + + bus_register_notifier(bus, nb); +} + +static int dma_debug_init(void) +{ + int i; + + /* Do not use dma_debug_initialized here, since we really want to be + * called to set dma_debug_initialized + */ + if (global_disable) + return 0; + + for (i = 0; i < HASH_SIZE; ++i) { + INIT_LIST_HEAD(&dma_entry_hash[i].list); + spin_lock_init(&dma_entry_hash[i].lock); + } + + if (dma_debug_fs_init() != 0) { + pr_err("DMA-API: error creating debugfs entries - disabling\n"); + global_disable = true; + + return 0; + } + + if (prealloc_memory(nr_prealloc_entries) != 0) { + pr_err("DMA-API: debugging out of memory error - disabled\n"); + global_disable = true; + + return 0; + } + + nr_total_entries = num_free_entries; + + dma_debug_initialized = true; + + pr_info("DMA-API: debugging enabled by kernel config\n"); + return 0; +} +core_initcall(dma_debug_init); + +static __init int dma_debug_cmdline(char *str) +{ + if (!str) + return -EINVAL; + + if (strncmp(str, "off", 3) == 0) { + pr_info("DMA-API: debugging disabled on kernel command line\n"); + global_disable = true; + } + + return 0; +} + +static __init int dma_debug_entries_cmdline(char *str) +{ + if (!str) + return -EINVAL; + if (!get_option(&str, &nr_prealloc_entries)) + nr_prealloc_entries = PREALLOC_DMA_DEBUG_ENTRIES; + return 0; +} + +__setup("dma_debug=", dma_debug_cmdline); +__setup("dma_debug_entries=", dma_debug_entries_cmdline); + +static void check_unmap(struct dma_debug_entry *ref) +{ + struct dma_debug_entry *entry; + struct hash_bucket *bucket; + unsigned long flags; + + bucket = get_hash_bucket(ref, &flags); + entry = bucket_find_exact(bucket, ref); + + if (!entry) { + /* must drop lock before calling dma_mapping_error */ + put_hash_bucket(bucket, &flags); + + if (dma_mapping_error(ref->dev, ref->dev_addr)) { + err_printk(ref->dev, NULL, + "DMA-API: device driver tries to free an " + "invalid DMA memory address\n"); + } else { + err_printk(ref->dev, NULL, + "DMA-API: device driver tries to free DMA " + "memory it has not allocated [device " + "address=0x%016llx] [size=%llu bytes]\n", + ref->dev_addr, ref->size); + } + return; + } + + if (ref->size != entry->size) { + err_printk(ref->dev, entry, "DMA-API: device driver frees " + "DMA memory with different size " + "[device address=0x%016llx] [map size=%llu bytes] " + "[unmap size=%llu bytes]\n", + ref->dev_addr, entry->size, ref->size); + } + + if (ref->type != entry->type) { + err_printk(ref->dev, entry, "DMA-API: device driver frees " + "DMA memory with wrong function " + "[device address=0x%016llx] [size=%llu bytes] " + "[mapped as %s] [unmapped as %s]\n", + ref->dev_addr, ref->size, + type2name[entry->type], type2name[ref->type]); + } else if ((entry->type == dma_debug_coherent) && + (phys_addr(ref) != phys_addr(entry))) { + err_printk(ref->dev, entry, "DMA-API: device driver frees " + "DMA memory with different CPU address " + "[device address=0x%016llx] [size=%llu bytes] " + "[cpu alloc address=0x%016llx] " + "[cpu free address=0x%016llx]", + ref->dev_addr, ref->size, + phys_addr(entry), + phys_addr(ref)); + } + + if (ref->sg_call_ents && ref->type == dma_debug_sg && + ref->sg_call_ents != entry->sg_call_ents) { + err_printk(ref->dev, entry, "DMA-API: device driver frees " + "DMA sg list with different entry count " + "[map count=%d] [unmap count=%d]\n", + entry->sg_call_ents, ref->sg_call_ents); + } + + /* + * This may be no bug in reality - but most implementations of the + * DMA API don't handle this properly, so check for it here + */ + if (ref->direction != entry->direction) { + err_printk(ref->dev, entry, "DMA-API: device driver frees " + "DMA memory with different direction " + "[device address=0x%016llx] [size=%llu bytes] " + "[mapped with %s] [unmapped with %s]\n", + ref->dev_addr, ref->size, + dir2name[entry->direction], + dir2name[ref->direction]); + } + + /* + * Drivers should use dma_mapping_error() to check the returned + * addresses of dma_map_single() and dma_map_page(). + * If not, print this warning message. See Documentation/DMA-API.txt. + */ + if (entry->map_err_type == MAP_ERR_NOT_CHECKED) { + err_printk(ref->dev, entry, + "DMA-API: device driver failed to check map error" + "[device address=0x%016llx] [size=%llu bytes] " + "[mapped as %s]", + ref->dev_addr, ref->size, + type2name[entry->type]); + } + + hash_bucket_del(entry); + dma_entry_free(entry); + + put_hash_bucket(bucket, &flags); +} + +static void check_for_stack(struct device *dev, + struct page *page, size_t offset) +{ + void *addr; + struct vm_struct *stack_vm_area = task_stack_vm_area(current); + + if (!stack_vm_area) { + /* Stack is direct-mapped. */ + if (PageHighMem(page)) + return; + addr = page_address(page) + offset; + if (object_is_on_stack(addr)) + err_printk(dev, NULL, "DMA-API: device driver maps memory from stack [addr=%p]\n", addr); + } else { + /* Stack is vmalloced. */ + int i; + + for (i = 0; i < stack_vm_area->nr_pages; i++) { + if (page != stack_vm_area->pages[i]) + continue; + + addr = (u8 *)current->stack + i * PAGE_SIZE + offset; + err_printk(dev, NULL, "DMA-API: device driver maps memory from stack [probable addr=%p]\n", addr); + break; + } + } +} + +static inline bool overlap(void *addr, unsigned long len, void *start, void *end) +{ + unsigned long a1 = (unsigned long)addr; + unsigned long b1 = a1 + len; + unsigned long a2 = (unsigned long)start; + unsigned long b2 = (unsigned long)end; + + return !(b1 <= a2 || a1 >= b2); +} + +static void check_for_illegal_area(struct device *dev, void *addr, unsigned long len) +{ + if (overlap(addr, len, _stext, _etext) || + overlap(addr, len, __start_rodata, __end_rodata)) + err_printk(dev, NULL, "DMA-API: device driver maps memory from kernel text or rodata [addr=%p] [len=%lu]\n", addr, len); +} + +static void check_sync(struct device *dev, + struct dma_debug_entry *ref, + bool to_cpu) +{ + struct dma_debug_entry *entry; + struct hash_bucket *bucket; + unsigned long flags; + + bucket = get_hash_bucket(ref, &flags); + + entry = bucket_find_contain(&bucket, ref, &flags); + + if (!entry) { + err_printk(dev, NULL, "DMA-API: device driver tries " + "to sync DMA memory it has not allocated " + "[device address=0x%016llx] [size=%llu bytes]\n", + (unsigned long long)ref->dev_addr, ref->size); + goto out; + } + + if (ref->size > entry->size) { + err_printk(dev, entry, "DMA-API: device driver syncs" + " DMA memory outside allocated range " + "[device address=0x%016llx] " + "[allocation size=%llu bytes] " + "[sync offset+size=%llu]\n", + entry->dev_addr, entry->size, + ref->size); + } + + if (entry->direction == DMA_BIDIRECTIONAL) + goto out; + + if (ref->direction != entry->direction) { + err_printk(dev, entry, "DMA-API: device driver syncs " + "DMA memory with different direction " + "[device address=0x%016llx] [size=%llu bytes] " + "[mapped with %s] [synced with %s]\n", + (unsigned long long)ref->dev_addr, entry->size, + dir2name[entry->direction], + dir2name[ref->direction]); + } + + if (to_cpu && !(entry->direction == DMA_FROM_DEVICE) && + !(ref->direction == DMA_TO_DEVICE)) + err_printk(dev, entry, "DMA-API: device driver syncs " + "device read-only DMA memory for cpu " + "[device address=0x%016llx] [size=%llu bytes] " + "[mapped with %s] [synced with %s]\n", + (unsigned long long)ref->dev_addr, entry->size, + dir2name[entry->direction], + dir2name[ref->direction]); + + if (!to_cpu && !(entry->direction == DMA_TO_DEVICE) && + !(ref->direction == DMA_FROM_DEVICE)) + err_printk(dev, entry, "DMA-API: device driver syncs " + "device write-only DMA memory to device " + "[device address=0x%016llx] [size=%llu bytes] " + "[mapped with %s] [synced with %s]\n", + (unsigned long long)ref->dev_addr, entry->size, + dir2name[entry->direction], + dir2name[ref->direction]); + + if (ref->sg_call_ents && ref->type == dma_debug_sg && + ref->sg_call_ents != entry->sg_call_ents) { + err_printk(ref->dev, entry, "DMA-API: device driver syncs " + "DMA sg list with different entry count " + "[map count=%d] [sync count=%d]\n", + entry->sg_call_ents, ref->sg_call_ents); + } + +out: + put_hash_bucket(bucket, &flags); +} + +static void check_sg_segment(struct device *dev, struct scatterlist *sg) +{ +#ifdef CONFIG_DMA_API_DEBUG_SG + unsigned int max_seg = dma_get_max_seg_size(dev); + u64 start, end, boundary = dma_get_seg_boundary(dev); + + /* + * Either the driver forgot to set dma_parms appropriately, or + * whoever generated the list forgot to check them. + */ + if (sg->length > max_seg) + err_printk(dev, NULL, "DMA-API: mapping sg segment longer than device claims to support [len=%u] [max=%u]\n", + sg->length, max_seg); + /* + * In some cases this could potentially be the DMA API + * implementation's fault, but it would usually imply that + * the scatterlist was built inappropriately to begin with. + */ + start = sg_dma_address(sg); + end = start + sg_dma_len(sg) - 1; + if ((start ^ end) & ~boundary) + err_printk(dev, NULL, "DMA-API: mapping sg segment across boundary [start=0x%016llx] [end=0x%016llx] [boundary=0x%016llx]\n", + start, end, boundary); +#endif +} + +void debug_dma_map_page(struct device *dev, struct page *page, size_t offset, + size_t size, int direction, dma_addr_t dma_addr, + bool map_single) +{ + struct dma_debug_entry *entry; + + if (unlikely(dma_debug_disabled())) + return; + + if (dma_mapping_error(dev, dma_addr)) + return; + + entry = dma_entry_alloc(); + if (!entry) + return; + + entry->dev = dev; + entry->type = dma_debug_page; + entry->pfn = page_to_pfn(page); + entry->offset = offset, + entry->dev_addr = dma_addr; + entry->size = size; + entry->direction = direction; + entry->map_err_type = MAP_ERR_NOT_CHECKED; + + if (map_single) + entry->type = dma_debug_single; + + check_for_stack(dev, page, offset); + + if (!PageHighMem(page)) { + void *addr = page_address(page) + offset; + + check_for_illegal_area(dev, addr, size); + } + + add_dma_entry(entry); +} +EXPORT_SYMBOL(debug_dma_map_page); + +void debug_dma_mapping_error(struct device *dev, dma_addr_t dma_addr) +{ + struct dma_debug_entry ref; + struct dma_debug_entry *entry; + struct hash_bucket *bucket; + unsigned long flags; + + if (unlikely(dma_debug_disabled())) + return; + + ref.dev = dev; + ref.dev_addr = dma_addr; + bucket = get_hash_bucket(&ref, &flags); + + list_for_each_entry(entry, &bucket->list, list) { + if (!exact_match(&ref, entry)) + continue; + + /* + * The same physical address can be mapped multiple + * times. Without a hardware IOMMU this results in the + * same device addresses being put into the dma-debug + * hash multiple times too. This can result in false + * positives being reported. Therefore we implement a + * best-fit algorithm here which updates the first entry + * from the hash which fits the reference value and is + * not currently listed as being checked. + */ + if (entry->map_err_type == MAP_ERR_NOT_CHECKED) { + entry->map_err_type = MAP_ERR_CHECKED; + break; + } + } + + put_hash_bucket(bucket, &flags); +} +EXPORT_SYMBOL(debug_dma_mapping_error); + +void debug_dma_unmap_page(struct device *dev, dma_addr_t addr, + size_t size, int direction, bool map_single) +{ + struct dma_debug_entry ref = { + .type = dma_debug_page, + .dev = dev, + .dev_addr = addr, + .size = size, + .direction = direction, + }; + + if (unlikely(dma_debug_disabled())) + return; + + if (map_single) + ref.type = dma_debug_single; + + check_unmap(&ref); +} +EXPORT_SYMBOL(debug_dma_unmap_page); + +void debug_dma_map_sg(struct device *dev, struct scatterlist *sg, + int nents, int mapped_ents, int direction) +{ + struct dma_debug_entry *entry; + struct scatterlist *s; + int i; + + if (unlikely(dma_debug_disabled())) + return; + + for_each_sg(sg, s, mapped_ents, i) { + entry = dma_entry_alloc(); + if (!entry) + return; + + entry->type = dma_debug_sg; + entry->dev = dev; + entry->pfn = page_to_pfn(sg_page(s)); + entry->offset = s->offset, + entry->size = sg_dma_len(s); + entry->dev_addr = sg_dma_address(s); + entry->direction = direction; + entry->sg_call_ents = nents; + entry->sg_mapped_ents = mapped_ents; + + check_for_stack(dev, sg_page(s), s->offset); + + if (!PageHighMem(sg_page(s))) { + check_for_illegal_area(dev, sg_virt(s), sg_dma_len(s)); + } + + check_sg_segment(dev, s); + + add_dma_entry(entry); + } +} +EXPORT_SYMBOL(debug_dma_map_sg); + +static int get_nr_mapped_entries(struct device *dev, + struct dma_debug_entry *ref) +{ + struct dma_debug_entry *entry; + struct hash_bucket *bucket; + unsigned long flags; + int mapped_ents; + + bucket = get_hash_bucket(ref, &flags); + entry = bucket_find_exact(bucket, ref); + mapped_ents = 0; + + if (entry) + mapped_ents = entry->sg_mapped_ents; + put_hash_bucket(bucket, &flags); + + return mapped_ents; +} + +void debug_dma_unmap_sg(struct device *dev, struct scatterlist *sglist, + int nelems, int dir) +{ + struct scatterlist *s; + int mapped_ents = 0, i; + + if (unlikely(dma_debug_disabled())) + return; + + for_each_sg(sglist, s, nelems, i) { + + struct dma_debug_entry ref = { + .type = dma_debug_sg, + .dev = dev, + .pfn = page_to_pfn(sg_page(s)), + .offset = s->offset, + .dev_addr = sg_dma_address(s), + .size = sg_dma_len(s), + .direction = dir, + .sg_call_ents = nelems, + }; + + if (mapped_ents && i >= mapped_ents) + break; + + if (!i) + mapped_ents = get_nr_mapped_entries(dev, &ref); + + check_unmap(&ref); + } +} +EXPORT_SYMBOL(debug_dma_unmap_sg); + +void debug_dma_alloc_coherent(struct device *dev, size_t size, + dma_addr_t dma_addr, void *virt) +{ + struct dma_debug_entry *entry; + + if (unlikely(dma_debug_disabled())) + return; + + if (unlikely(virt == NULL)) + return; + + /* handle vmalloc and linear addresses */ + if (!is_vmalloc_addr(virt) && !virt_addr_valid(virt)) + return; + + entry = dma_entry_alloc(); + if (!entry) + return; + + entry->type = dma_debug_coherent; + entry->dev = dev; + entry->offset = offset_in_page(virt); + entry->size = size; + entry->dev_addr = dma_addr; + entry->direction = DMA_BIDIRECTIONAL; + + if (is_vmalloc_addr(virt)) + entry->pfn = vmalloc_to_pfn(virt); + else + entry->pfn = page_to_pfn(virt_to_page(virt)); + + add_dma_entry(entry); +} +EXPORT_SYMBOL(debug_dma_alloc_coherent); + +void debug_dma_free_coherent(struct device *dev, size_t size, + void *virt, dma_addr_t addr) +{ + struct dma_debug_entry ref = { + .type = dma_debug_coherent, + .dev = dev, + .offset = offset_in_page(virt), + .dev_addr = addr, + .size = size, + .direction = DMA_BIDIRECTIONAL, + }; + + /* handle vmalloc and linear addresses */ + if (!is_vmalloc_addr(virt) && !virt_addr_valid(virt)) + return; + + if (is_vmalloc_addr(virt)) + ref.pfn = vmalloc_to_pfn(virt); + else + ref.pfn = page_to_pfn(virt_to_page(virt)); + + if (unlikely(dma_debug_disabled())) + return; + + check_unmap(&ref); +} +EXPORT_SYMBOL(debug_dma_free_coherent); + +void debug_dma_map_resource(struct device *dev, phys_addr_t addr, size_t size, + int direction, dma_addr_t dma_addr) +{ + struct dma_debug_entry *entry; + + if (unlikely(dma_debug_disabled())) + return; + + entry = dma_entry_alloc(); + if (!entry) + return; + + entry->type = dma_debug_resource; + entry->dev = dev; + entry->pfn = PHYS_PFN(addr); + entry->offset = offset_in_page(addr); + entry->size = size; + entry->dev_addr = dma_addr; + entry->direction = direction; + entry->map_err_type = MAP_ERR_NOT_CHECKED; + + add_dma_entry(entry); +} +EXPORT_SYMBOL(debug_dma_map_resource); + +void debug_dma_unmap_resource(struct device *dev, dma_addr_t dma_addr, + size_t size, int direction) +{ + struct dma_debug_entry ref = { + .type = dma_debug_resource, + .dev = dev, + .dev_addr = dma_addr, + .size = size, + .direction = direction, + }; + + if (unlikely(dma_debug_disabled())) + return; + + check_unmap(&ref); +} +EXPORT_SYMBOL(debug_dma_unmap_resource); + +void debug_dma_sync_single_for_cpu(struct device *dev, dma_addr_t dma_handle, + size_t size, int direction) +{ + struct dma_debug_entry ref; + + if (unlikely(dma_debug_disabled())) + return; + + ref.type = dma_debug_single; + ref.dev = dev; + ref.dev_addr = dma_handle; + ref.size = size; + ref.direction = direction; + ref.sg_call_ents = 0; + + check_sync(dev, &ref, true); +} +EXPORT_SYMBOL(debug_dma_sync_single_for_cpu); + +void debug_dma_sync_single_for_device(struct device *dev, + dma_addr_t dma_handle, size_t size, + int direction) +{ + struct dma_debug_entry ref; + + if (unlikely(dma_debug_disabled())) + return; + + ref.type = dma_debug_single; + ref.dev = dev; + ref.dev_addr = dma_handle; + ref.size = size; + ref.direction = direction; + ref.sg_call_ents = 0; + + check_sync(dev, &ref, false); +} +EXPORT_SYMBOL(debug_dma_sync_single_for_device); + +void debug_dma_sync_single_range_for_cpu(struct device *dev, + dma_addr_t dma_handle, + unsigned long offset, size_t size, + int direction) +{ + struct dma_debug_entry ref; + + if (unlikely(dma_debug_disabled())) + return; + + ref.type = dma_debug_single; + ref.dev = dev; + ref.dev_addr = dma_handle; + ref.size = offset + size; + ref.direction = direction; + ref.sg_call_ents = 0; + + check_sync(dev, &ref, true); +} +EXPORT_SYMBOL(debug_dma_sync_single_range_for_cpu); + +void debug_dma_sync_single_range_for_device(struct device *dev, + dma_addr_t dma_handle, + unsigned long offset, + size_t size, int direction) +{ + struct dma_debug_entry ref; + + if (unlikely(dma_debug_disabled())) + return; + + ref.type = dma_debug_single; + ref.dev = dev; + ref.dev_addr = dma_handle; + ref.size = offset + size; + ref.direction = direction; + ref.sg_call_ents = 0; + + check_sync(dev, &ref, false); +} +EXPORT_SYMBOL(debug_dma_sync_single_range_for_device); + +void debug_dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg, + int nelems, int direction) +{ + struct scatterlist *s; + int mapped_ents = 0, i; + + if (unlikely(dma_debug_disabled())) + return; + + for_each_sg(sg, s, nelems, i) { + + struct dma_debug_entry ref = { + .type = dma_debug_sg, + .dev = dev, + .pfn = page_to_pfn(sg_page(s)), + .offset = s->offset, + .dev_addr = sg_dma_address(s), + .size = sg_dma_len(s), + .direction = direction, + .sg_call_ents = nelems, + }; + + if (!i) + mapped_ents = get_nr_mapped_entries(dev, &ref); + + if (i >= mapped_ents) + break; + + check_sync(dev, &ref, true); + } +} +EXPORT_SYMBOL(debug_dma_sync_sg_for_cpu); + +void debug_dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg, + int nelems, int direction) +{ + struct scatterlist *s; + int mapped_ents = 0, i; + + if (unlikely(dma_debug_disabled())) + return; + + for_each_sg(sg, s, nelems, i) { + + struct dma_debug_entry ref = { + .type = dma_debug_sg, + .dev = dev, + .pfn = page_to_pfn(sg_page(s)), + .offset = s->offset, + .dev_addr = sg_dma_address(s), + .size = sg_dma_len(s), + .direction = direction, + .sg_call_ents = nelems, + }; + if (!i) + mapped_ents = get_nr_mapped_entries(dev, &ref); + + if (i >= mapped_ents) + break; + + check_sync(dev, &ref, false); + } +} +EXPORT_SYMBOL(debug_dma_sync_sg_for_device); + +static int __init dma_debug_driver_setup(char *str) +{ + int i; + + for (i = 0; i < NAME_MAX_LEN - 1; ++i, ++str) { + current_driver_name[i] = *str; + if (*str == 0) + break; + } + + if (current_driver_name[0]) + pr_info("DMA-API: enable driver filter for driver [%s]\n", + current_driver_name); + + + return 1; +} +__setup("dma_debug_driver=", dma_debug_driver_setup); diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c new file mode 100644 index 000000000000..8be8106270c2 --- /dev/null +++ b/kernel/dma/direct.c @@ -0,0 +1,204 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * DMA operations that map physical memory directly without using an IOMMU or + * flushing caches. + */ +#include +#include +#include +#include +#include +#include +#include + +#define DIRECT_MAPPING_ERROR 0 + +/* + * Most architectures use ZONE_DMA for the first 16 Megabytes, but + * some use it for entirely different regions: + */ +#ifndef ARCH_ZONE_DMA_BITS +#define ARCH_ZONE_DMA_BITS 24 +#endif + +/* + * For AMD SEV all DMA must be to unencrypted addresses. + */ +static inline bool force_dma_unencrypted(void) +{ + return sev_active(); +} + +static bool +check_addr(struct device *dev, dma_addr_t dma_addr, size_t size, + const char *caller) +{ + if (unlikely(dev && !dma_capable(dev, dma_addr, size))) { + if (!dev->dma_mask) { + dev_err(dev, + "%s: call on device without dma_mask\n", + caller); + return false; + } + + if (*dev->dma_mask >= DMA_BIT_MASK(32)) { + dev_err(dev, + "%s: overflow %pad+%zu of device mask %llx\n", + caller, &dma_addr, size, *dev->dma_mask); + } + return false; + } + return true; +} + +static bool dma_coherent_ok(struct device *dev, phys_addr_t phys, size_t size) +{ + dma_addr_t addr = force_dma_unencrypted() ? + __phys_to_dma(dev, phys) : phys_to_dma(dev, phys); + return addr + size - 1 <= dev->coherent_dma_mask; +} + +void *dma_direct_alloc(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; + void *ret; + + /* we always manually zero the memory once we are done: */ + gfp &= ~__GFP_ZERO; + + /* GFP_DMA32 and GFP_DMA are no ops without the corresponding zones: */ + if (dev->coherent_dma_mask <= DMA_BIT_MASK(ARCH_ZONE_DMA_BITS)) + gfp |= GFP_DMA; + if (dev->coherent_dma_mask <= DMA_BIT_MASK(32) && !(gfp & GFP_DMA)) + gfp |= GFP_DMA32; + +again: + /* CMA can be used only in the context which permits sleeping */ + if (gfpflags_allow_blocking(gfp)) { + page = dma_alloc_from_contiguous(dev, count, page_order, gfp); + if (page && !dma_coherent_ok(dev, page_to_phys(page), size)) { + dma_release_from_contiguous(dev, page, count); + page = NULL; + } + } + if (!page) + page = alloc_pages_node(dev_to_node(dev), gfp, page_order); + + if (page && !dma_coherent_ok(dev, page_to_phys(page), size)) { + __free_pages(page, page_order); + page = NULL; + + if (IS_ENABLED(CONFIG_ZONE_DMA32) && + dev->coherent_dma_mask < DMA_BIT_MASK(64) && + !(gfp & (GFP_DMA32 | GFP_DMA))) { + gfp |= GFP_DMA32; + goto again; + } + + if (IS_ENABLED(CONFIG_ZONE_DMA) && + dev->coherent_dma_mask < DMA_BIT_MASK(32) && + !(gfp & GFP_DMA)) { + gfp = (gfp & ~GFP_DMA32) | GFP_DMA; + goto again; + } + } + + if (!page) + return NULL; + ret = page_address(page); + if (force_dma_unencrypted()) { + set_memory_decrypted((unsigned long)ret, 1 << page_order); + *dma_handle = __phys_to_dma(dev, page_to_phys(page)); + } else { + *dma_handle = phys_to_dma(dev, page_to_phys(page)); + } + memset(ret, 0, 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(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_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) +{ + dma_addr_t dma_addr = phys_to_dma(dev, page_to_phys(page)) + offset; + + if (!check_addr(dev, dma_addr, size, __func__)) + return DIRECT_MAPPING_ERROR; + return dma_addr; +} + +int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl, int nents, + enum dma_data_direction dir, unsigned long attrs) +{ + int i; + struct scatterlist *sg; + + for_each_sg(sgl, sg, nents, i) { + BUG_ON(!sg_page(sg)); + + sg_dma_address(sg) = phys_to_dma(dev, sg_phys(sg)); + if (!check_addr(dev, sg_dma_address(sg), sg->length, __func__)) + return 0; + sg_dma_len(sg) = sg->length; + } + + return nents; +} + +int dma_direct_supported(struct device *dev, u64 mask) +{ +#ifdef CONFIG_ZONE_DMA + if (mask < DMA_BIT_MASK(ARCH_ZONE_DMA_BITS)) + return 0; +#else + /* + * Because 32-bit DMA masks are so common we expect every architecture + * to be able to satisfy them - either by not supporting more physical + * memory, or by providing a ZONE_DMA32. If neither is the case, the + * architecture needs to use an IOMMU instead of the direct mapping. + */ + if (mask < DMA_BIT_MASK(32)) + return 0; +#endif + /* + * Various PCI/PCIe bridges have broken support for > 32bit DMA even + * if the device itself might support it. + */ + if (dev->dma_32bit_limit && mask > DMA_BIT_MASK(32)) + return 0; + return 1; +} + +int dma_direct_mapping_error(struct device *dev, dma_addr_t dma_addr) +{ + return dma_addr == DIRECT_MAPPING_ERROR; +} + +const struct dma_map_ops dma_direct_ops = { + .alloc = dma_direct_alloc, + .free = dma_direct_free, + .map_page = dma_direct_map_page, + .map_sg = dma_direct_map_sg, + .dma_supported = dma_direct_supported, + .mapping_error = dma_direct_mapping_error, +}; +EXPORT_SYMBOL(dma_direct_ops); diff --git a/kernel/dma/mapping.c b/kernel/dma/mapping.c new file mode 100644 index 000000000000..d2a92ddaac4d --- /dev/null +++ b/kernel/dma/mapping.c @@ -0,0 +1,345 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * arch-independent dma-mapping routines + * + * Copyright (c) 2006 SUSE Linux Products GmbH + * Copyright (c) 2006 Tejun Heo + */ + +#include +#include +#include +#include +#include +#include +#include + +/* + * Managed DMA API + */ +struct dma_devres { + size_t size; + void *vaddr; + dma_addr_t dma_handle; + unsigned long attrs; +}; + +static void dmam_release(struct device *dev, void *res) +{ + struct dma_devres *this = res; + + dma_free_attrs(dev, this->size, this->vaddr, this->dma_handle, + this->attrs); +} + +static int dmam_match(struct device *dev, void *res, void *match_data) +{ + struct dma_devres *this = res, *match = match_data; + + if (this->vaddr == match->vaddr) { + WARN_ON(this->size != match->size || + this->dma_handle != match->dma_handle); + return 1; + } + return 0; +} + +/** + * dmam_alloc_coherent - Managed dma_alloc_coherent() + * @dev: Device to allocate coherent memory for + * @size: Size of allocation + * @dma_handle: Out argument for allocated DMA handle + * @gfp: Allocation flags + * + * Managed dma_alloc_coherent(). Memory allocated using this function + * will be automatically released on driver detach. + * + * RETURNS: + * Pointer to allocated memory on success, NULL on failure. + */ +void *dmam_alloc_coherent(struct device *dev, size_t size, + dma_addr_t *dma_handle, gfp_t gfp) +{ + struct dma_devres *dr; + void *vaddr; + + dr = devres_alloc(dmam_release, sizeof(*dr), gfp); + if (!dr) + return NULL; + + vaddr = dma_alloc_coherent(dev, size, dma_handle, gfp); + if (!vaddr) { + devres_free(dr); + return NULL; + } + + dr->vaddr = vaddr; + dr->dma_handle = *dma_handle; + dr->size = size; + + devres_add(dev, dr); + + return vaddr; +} +EXPORT_SYMBOL(dmam_alloc_coherent); + +/** + * dmam_free_coherent - Managed dma_free_coherent() + * @dev: Device to free coherent memory for + * @size: Size of allocation + * @vaddr: Virtual address of the memory to free + * @dma_handle: DMA handle of the memory to free + * + * Managed dma_free_coherent(). + */ +void dmam_free_coherent(struct device *dev, size_t size, void *vaddr, + dma_addr_t dma_handle) +{ + struct dma_devres match_data = { size, vaddr, dma_handle }; + + dma_free_coherent(dev, size, vaddr, dma_handle); + WARN_ON(devres_destroy(dev, dmam_release, dmam_match, &match_data)); +} +EXPORT_SYMBOL(dmam_free_coherent); + +/** + * dmam_alloc_attrs - Managed dma_alloc_attrs() + * @dev: Device to allocate non_coherent memory for + * @size: Size of allocation + * @dma_handle: Out argument for allocated DMA handle + * @gfp: Allocation flags + * @attrs: Flags in the DMA_ATTR_* namespace. + * + * Managed dma_alloc_attrs(). Memory allocated using this function will be + * automatically released on driver detach. + * + * RETURNS: + * Pointer to allocated memory on success, NULL on failure. + */ +void *dmam_alloc_attrs(struct device *dev, size_t size, dma_addr_t *dma_handle, + gfp_t gfp, unsigned long attrs) +{ + struct dma_devres *dr; + void *vaddr; + + dr = devres_alloc(dmam_release, sizeof(*dr), gfp); + if (!dr) + return NULL; + + vaddr = dma_alloc_attrs(dev, size, dma_handle, gfp, attrs); + if (!vaddr) { + devres_free(dr); + return NULL; + } + + dr->vaddr = vaddr; + dr->dma_handle = *dma_handle; + dr->size = size; + dr->attrs = attrs; + + devres_add(dev, dr); + + return vaddr; +} +EXPORT_SYMBOL(dmam_alloc_attrs); + +#ifdef CONFIG_HAVE_GENERIC_DMA_COHERENT + +static void dmam_coherent_decl_release(struct device *dev, void *res) +{ + dma_release_declared_memory(dev); +} + +/** + * dmam_declare_coherent_memory - Managed dma_declare_coherent_memory() + * @dev: Device to declare coherent memory for + * @phys_addr: Physical address of coherent memory to be declared + * @device_addr: Device address of coherent memory to be declared + * @size: Size of coherent memory to be declared + * @flags: Flags + * + * Managed dma_declare_coherent_memory(). + * + * RETURNS: + * 0 on success, -errno on failure. + */ +int dmam_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr, + dma_addr_t device_addr, size_t size, int flags) +{ + void *res; + int rc; + + res = devres_alloc(dmam_coherent_decl_release, 0, GFP_KERNEL); + if (!res) + return -ENOMEM; + + rc = dma_declare_coherent_memory(dev, phys_addr, device_addr, size, + flags); + if (!rc) + devres_add(dev, res); + else + devres_free(res); + + return rc; +} +EXPORT_SYMBOL(dmam_declare_coherent_memory); + +/** + * dmam_release_declared_memory - Managed dma_release_declared_memory(). + * @dev: Device to release declared coherent memory for + * + * Managed dmam_release_declared_memory(). + */ +void dmam_release_declared_memory(struct device *dev) +{ + WARN_ON(devres_destroy(dev, dmam_coherent_decl_release, NULL, NULL)); +} +EXPORT_SYMBOL(dmam_release_declared_memory); + +#endif + +/* + * Create scatter-list for the already allocated DMA buffer. + */ +int dma_common_get_sgtable(struct device *dev, struct sg_table *sgt, + void *cpu_addr, dma_addr_t handle, size_t size) +{ + struct page *page = virt_to_page(cpu_addr); + int ret; + + ret = sg_alloc_table(sgt, 1, GFP_KERNEL); + if (unlikely(ret)) + return ret; + + sg_set_page(sgt->sgl, page, PAGE_ALIGN(size), 0); + return 0; +} +EXPORT_SYMBOL(dma_common_get_sgtable); + +/* + * Create userspace mapping for the DMA-coherent memory. + */ +int dma_common_mmap(struct device *dev, struct vm_area_struct *vma, + void *cpu_addr, dma_addr_t dma_addr, size_t size) +{ + int ret = -ENXIO; +#ifndef CONFIG_ARCH_NO_COHERENT_DMA_MMAP + unsigned long user_count = vma_pages(vma); + unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT; + unsigned long off = vma->vm_pgoff; + + vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); + + if (dma_mmap_from_dev_coherent(dev, vma, cpu_addr, size, &ret)) + return ret; + + if (off < count && user_count <= (count - off)) + ret = remap_pfn_range(vma, vma->vm_start, + page_to_pfn(virt_to_page(cpu_addr)) + off, + user_count << PAGE_SHIFT, + vma->vm_page_prot); +#endif /* !CONFIG_ARCH_NO_COHERENT_DMA_MMAP */ + + return ret; +} +EXPORT_SYMBOL(dma_common_mmap); + +#ifdef CONFIG_MMU +static struct vm_struct *__dma_common_pages_remap(struct page **pages, + size_t size, unsigned long vm_flags, pgprot_t prot, + const void *caller) +{ + struct vm_struct *area; + + area = get_vm_area_caller(size, vm_flags, caller); + if (!area) + return NULL; + + if (map_vm_area(area, prot, pages)) { + vunmap(area->addr); + return NULL; + } + + return area; +} + +/* + * remaps an array of PAGE_SIZE pages into another vm_area + * Cannot be used in non-sleeping contexts + */ +void *dma_common_pages_remap(struct page **pages, size_t size, + unsigned long vm_flags, pgprot_t prot, + const void *caller) +{ + struct vm_struct *area; + + area = __dma_common_pages_remap(pages, size, vm_flags, prot, caller); + if (!area) + return NULL; + + area->pages = pages; + + return area->addr; +} + +/* + * remaps an allocated contiguous region into another vm_area. + * Cannot be used in non-sleeping contexts + */ + +void *dma_common_contiguous_remap(struct page *page, size_t size, + unsigned long vm_flags, + pgprot_t prot, const void *caller) +{ + int i; + struct page **pages; + struct vm_struct *area; + + pages = kmalloc(sizeof(struct page *) << get_order(size), GFP_KERNEL); + if (!pages) + return NULL; + + for (i = 0; i < (size >> PAGE_SHIFT); i++) + pages[i] = nth_page(page, i); + + area = __dma_common_pages_remap(pages, size, vm_flags, prot, caller); + + kfree(pages); + + if (!area) + return NULL; + return area->addr; +} + +/* + * unmaps a range previously mapped by dma_common_*_remap + */ +void dma_common_free_remap(void *cpu_addr, size_t size, unsigned long vm_flags) +{ + struct vm_struct *area = find_vm_area(cpu_addr); + + if (!area || (area->flags & vm_flags) != vm_flags) { + WARN(1, "trying to free invalid coherent area: %p\n", cpu_addr); + return; + } + + unmap_kernel_range((unsigned long)cpu_addr, PAGE_ALIGN(size)); + vunmap(cpu_addr); +} +#endif + +/* + * enables DMA API use for a device + */ +int dma_configure(struct device *dev) +{ + if (dev->bus->dma_configure) + return dev->bus->dma_configure(dev); + return 0; +} + +void dma_deconfigure(struct device *dev) +{ + of_dma_deconfigure(dev); + acpi_dma_deconfigure(dev); +} diff --git a/kernel/dma/noncoherent.c b/kernel/dma/noncoherent.c new file mode 100644 index 000000000000..79e9a757387f --- /dev/null +++ b/kernel/dma/noncoherent.c @@ -0,0 +1,102 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2018 Christoph Hellwig. + * + * DMA operations that map physical memory directly without providing cache + * coherence. + */ +#include +#include +#include +#include +#include + +static void dma_noncoherent_sync_single_for_device(struct device *dev, + dma_addr_t addr, size_t size, enum dma_data_direction dir) +{ + arch_sync_dma_for_device(dev, dma_to_phys(dev, addr), size, dir); +} + +static void dma_noncoherent_sync_sg_for_device(struct device *dev, + struct scatterlist *sgl, int nents, enum dma_data_direction dir) +{ + struct scatterlist *sg; + int i; + + for_each_sg(sgl, sg, nents, i) + arch_sync_dma_for_device(dev, sg_phys(sg), sg->length, dir); +} + +static dma_addr_t dma_noncoherent_map_page(struct device *dev, struct page *page, + unsigned long offset, size_t size, enum dma_data_direction dir, + unsigned long attrs) +{ + dma_addr_t addr; + + addr = dma_direct_map_page(dev, page, offset, size, dir, attrs); + if (!dma_mapping_error(dev, addr) && !(attrs & DMA_ATTR_SKIP_CPU_SYNC)) + arch_sync_dma_for_device(dev, page_to_phys(page) + offset, + size, dir); + return addr; +} + +static int dma_noncoherent_map_sg(struct device *dev, struct scatterlist *sgl, + int nents, enum dma_data_direction dir, unsigned long attrs) +{ + nents = dma_direct_map_sg(dev, sgl, nents, dir, attrs); + if (nents > 0 && !(attrs & DMA_ATTR_SKIP_CPU_SYNC)) + dma_noncoherent_sync_sg_for_device(dev, sgl, nents, dir); + return nents; +} + +#ifdef CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU +static void dma_noncoherent_sync_single_for_cpu(struct device *dev, + dma_addr_t addr, size_t size, enum dma_data_direction dir) +{ + arch_sync_dma_for_cpu(dev, dma_to_phys(dev, addr), size, dir); +} + +static void dma_noncoherent_sync_sg_for_cpu(struct device *dev, + struct scatterlist *sgl, int nents, enum dma_data_direction dir) +{ + struct scatterlist *sg; + int i; + + for_each_sg(sgl, sg, nents, i) + arch_sync_dma_for_cpu(dev, sg_phys(sg), sg->length, dir); +} + +static void dma_noncoherent_unmap_page(struct device *dev, dma_addr_t addr, + size_t size, enum dma_data_direction dir, unsigned long attrs) +{ + if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC)) + dma_noncoherent_sync_single_for_cpu(dev, addr, size, dir); +} + +static void dma_noncoherent_unmap_sg(struct device *dev, struct scatterlist *sgl, + int nents, enum dma_data_direction dir, unsigned long attrs) +{ + if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC)) + dma_noncoherent_sync_sg_for_cpu(dev, sgl, nents, dir); +} +#endif + +const struct dma_map_ops dma_noncoherent_ops = { + .alloc = arch_dma_alloc, + .free = arch_dma_free, + .mmap = arch_dma_mmap, + .sync_single_for_device = dma_noncoherent_sync_single_for_device, + .sync_sg_for_device = dma_noncoherent_sync_sg_for_device, + .map_page = dma_noncoherent_map_page, + .map_sg = dma_noncoherent_map_sg, +#ifdef CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU + .sync_single_for_cpu = dma_noncoherent_sync_single_for_cpu, + .sync_sg_for_cpu = dma_noncoherent_sync_sg_for_cpu, + .unmap_page = dma_noncoherent_unmap_page, + .unmap_sg = dma_noncoherent_unmap_sg, +#endif + .dma_supported = dma_direct_supported, + .mapping_error = dma_direct_mapping_error, + .cache_sync = arch_dma_cache_sync, +}; +EXPORT_SYMBOL(dma_noncoherent_ops); diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c new file mode 100644 index 000000000000..04b68d9dffac --- /dev/null +++ b/kernel/dma/swiotlb.c @@ -0,0 +1,1087 @@ +/* + * Dynamic DMA mapping support. + * + * This implementation is a fallback for platforms that do not support + * I/O TLBs (aka DMA address translation hardware). + * Copyright (C) 2000 Asit Mallick + * Copyright (C) 2000 Goutham Rao + * Copyright (C) 2000, 2003 Hewlett-Packard Co + * David Mosberger-Tang + * + * 03/05/07 davidm Switch from PCI-DMA to generic device DMA API. + * 00/12/13 davidm Rename to swiotlb.c and add mark_clean() to avoid + * unnecessary i-cache flushing. + * 04/07/.. ak Better overflow handling. Assorted fixes. + * 05/09/10 linville Add support for syncing ranges, support syncing for + * DMA_BIDIRECTIONAL mappings, miscellaneous cleanup. + * 08/12/11 beckyb Add highmem support + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include + +#include +#include +#include + +#define CREATE_TRACE_POINTS +#include + +#define OFFSET(val,align) ((unsigned long) \ + ( (val) & ( (align) - 1))) + +#define SLABS_PER_PAGE (1 << (PAGE_SHIFT - IO_TLB_SHIFT)) + +/* + * Minimum IO TLB size to bother booting with. Systems with mainly + * 64bit capable cards will only lightly use the swiotlb. If we can't + * allocate a contiguous 1MB, we're probably in trouble anyway. + */ +#define IO_TLB_MIN_SLABS ((1<<20) >> IO_TLB_SHIFT) + +enum swiotlb_force swiotlb_force; + +/* + * Used to do a quick range check in swiotlb_tbl_unmap_single and + * swiotlb_tbl_sync_single_*, to see if the memory was in fact allocated by this + * API. + */ +static phys_addr_t io_tlb_start, io_tlb_end; + +/* + * The number of IO TLB blocks (in groups of 64) between io_tlb_start and + * io_tlb_end. This is command line adjustable via setup_io_tlb_npages. + */ +static unsigned long io_tlb_nslabs; + +/* + * When the IOMMU overflows we return a fallback buffer. This sets the size. + */ +static unsigned long io_tlb_overflow = 32*1024; + +static phys_addr_t io_tlb_overflow_buffer; + +/* + * This is a free list describing the number of free entries available from + * each index + */ +static unsigned int *io_tlb_list; +static unsigned int io_tlb_index; + +/* + * Max segment that we can provide which (if pages are contingous) will + * not be bounced (unless SWIOTLB_FORCE is set). + */ +unsigned int max_segment; + +/* + * We need to save away the original address corresponding to a mapped entry + * for the sync operations. + */ +#define INVALID_PHYS_ADDR (~(phys_addr_t)0) +static phys_addr_t *io_tlb_orig_addr; + +/* + * Protect the above data structures in the map and unmap calls + */ +static DEFINE_SPINLOCK(io_tlb_lock); + +static int late_alloc; + +static int __init +setup_io_tlb_npages(char *str) +{ + if (isdigit(*str)) { + io_tlb_nslabs = simple_strtoul(str, &str, 0); + /* avoid tail segment of size < IO_TLB_SEGSIZE */ + io_tlb_nslabs = ALIGN(io_tlb_nslabs, IO_TLB_SEGSIZE); + } + if (*str == ',') + ++str; + if (!strcmp(str, "force")) { + swiotlb_force = SWIOTLB_FORCE; + } else if (!strcmp(str, "noforce")) { + swiotlb_force = SWIOTLB_NO_FORCE; + io_tlb_nslabs = 1; + } + + return 0; +} +early_param("swiotlb", setup_io_tlb_npages); +/* make io_tlb_overflow tunable too? */ + +unsigned long swiotlb_nr_tbl(void) +{ + return io_tlb_nslabs; +} +EXPORT_SYMBOL_GPL(swiotlb_nr_tbl); + +unsigned int swiotlb_max_segment(void) +{ + return max_segment; +} +EXPORT_SYMBOL_GPL(swiotlb_max_segment); + +void swiotlb_set_max_segment(unsigned int val) +{ + if (swiotlb_force == SWIOTLB_FORCE) + max_segment = 1; + else + max_segment = rounddown(val, PAGE_SIZE); +} + +/* default to 64MB */ +#define IO_TLB_DEFAULT_SIZE (64UL<<20) +unsigned long swiotlb_size_or_default(void) +{ + unsigned long size; + + size = io_tlb_nslabs << IO_TLB_SHIFT; + + return size ? size : (IO_TLB_DEFAULT_SIZE); +} + +static bool no_iotlb_memory; + +void swiotlb_print_info(void) +{ + unsigned long bytes = io_tlb_nslabs << IO_TLB_SHIFT; + unsigned char *vstart, *vend; + + if (no_iotlb_memory) { + pr_warn("software IO TLB: No low mem\n"); + return; + } + + vstart = phys_to_virt(io_tlb_start); + vend = phys_to_virt(io_tlb_end); + + printk(KERN_INFO "software IO TLB [mem %#010llx-%#010llx] (%luMB) mapped at [%p-%p]\n", + (unsigned long long)io_tlb_start, + (unsigned long long)io_tlb_end, + bytes >> 20, vstart, vend - 1); +} + +/* + * Early SWIOTLB allocation may be too early to allow an architecture to + * perform the desired operations. This function allows the architecture to + * call SWIOTLB when the operations are possible. It needs to be called + * before the SWIOTLB memory is used. + */ +void __init swiotlb_update_mem_attributes(void) +{ + void *vaddr; + unsigned long bytes; + + if (no_iotlb_memory || late_alloc) + return; + + vaddr = phys_to_virt(io_tlb_start); + bytes = PAGE_ALIGN(io_tlb_nslabs << IO_TLB_SHIFT); + set_memory_decrypted((unsigned long)vaddr, bytes >> PAGE_SHIFT); + memset(vaddr, 0, bytes); + + vaddr = phys_to_virt(io_tlb_overflow_buffer); + bytes = PAGE_ALIGN(io_tlb_overflow); + set_memory_decrypted((unsigned long)vaddr, bytes >> PAGE_SHIFT); + memset(vaddr, 0, bytes); +} + +int __init swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose) +{ + void *v_overflow_buffer; + unsigned long i, bytes; + + bytes = nslabs << IO_TLB_SHIFT; + + io_tlb_nslabs = nslabs; + io_tlb_start = __pa(tlb); + io_tlb_end = io_tlb_start + bytes; + + /* + * Get the overflow emergency buffer + */ + v_overflow_buffer = memblock_virt_alloc_low_nopanic( + PAGE_ALIGN(io_tlb_overflow), + PAGE_SIZE); + if (!v_overflow_buffer) + return -ENOMEM; + + io_tlb_overflow_buffer = __pa(v_overflow_buffer); + + /* + * Allocate and initialize the free list array. This array is used + * to find contiguous free memory regions of size up to IO_TLB_SEGSIZE + * between io_tlb_start and io_tlb_end. + */ + io_tlb_list = memblock_virt_alloc( + PAGE_ALIGN(io_tlb_nslabs * sizeof(int)), + PAGE_SIZE); + io_tlb_orig_addr = memblock_virt_alloc( + PAGE_ALIGN(io_tlb_nslabs * sizeof(phys_addr_t)), + PAGE_SIZE); + for (i = 0; i < io_tlb_nslabs; i++) { + io_tlb_list[i] = IO_TLB_SEGSIZE - OFFSET(i, IO_TLB_SEGSIZE); + io_tlb_orig_addr[i] = INVALID_PHYS_ADDR; + } + io_tlb_index = 0; + + if (verbose) + swiotlb_print_info(); + + swiotlb_set_max_segment(io_tlb_nslabs << IO_TLB_SHIFT); + return 0; +} + +/* + * Statically reserve bounce buffer space and initialize bounce buffer data + * structures for the software IO TLB used to implement the DMA API. + */ +void __init +swiotlb_init(int verbose) +{ + size_t default_size = IO_TLB_DEFAULT_SIZE; + unsigned char *vstart; + unsigned long bytes; + + if (!io_tlb_nslabs) { + io_tlb_nslabs = (default_size >> IO_TLB_SHIFT); + io_tlb_nslabs = ALIGN(io_tlb_nslabs, IO_TLB_SEGSIZE); + } + + bytes = io_tlb_nslabs << IO_TLB_SHIFT; + + /* Get IO TLB memory from the low pages */ + vstart = memblock_virt_alloc_low_nopanic(PAGE_ALIGN(bytes), PAGE_SIZE); + if (vstart && !swiotlb_init_with_tbl(vstart, io_tlb_nslabs, verbose)) + return; + + if (io_tlb_start) + memblock_free_early(io_tlb_start, + PAGE_ALIGN(io_tlb_nslabs << IO_TLB_SHIFT)); + pr_warn("Cannot allocate SWIOTLB buffer"); + no_iotlb_memory = true; +} + +/* + * Systems with larger DMA zones (those that don't support ISA) can + * initialize the swiotlb later using the slab allocator if needed. + * This should be just like above, but with some error catching. + */ +int +swiotlb_late_init_with_default_size(size_t default_size) +{ + unsigned long bytes, req_nslabs = io_tlb_nslabs; + unsigned char *vstart = NULL; + unsigned int order; + int rc = 0; + + if (!io_tlb_nslabs) { + io_tlb_nslabs = (default_size >> IO_TLB_SHIFT); + io_tlb_nslabs = ALIGN(io_tlb_nslabs, IO_TLB_SEGSIZE); + } + + /* + * Get IO TLB memory from the low pages + */ + order = get_order(io_tlb_nslabs << IO_TLB_SHIFT); + io_tlb_nslabs = SLABS_PER_PAGE << order; + bytes = io_tlb_nslabs << IO_TLB_SHIFT; + + while ((SLABS_PER_PAGE << order) > IO_TLB_MIN_SLABS) { + vstart = (void *)__get_free_pages(GFP_DMA | __GFP_NOWARN, + order); + if (vstart) + break; + order--; + } + + if (!vstart) { + io_tlb_nslabs = req_nslabs; + return -ENOMEM; + } + if (order != get_order(bytes)) { + printk(KERN_WARNING "Warning: only able to allocate %ld MB " + "for software IO TLB\n", (PAGE_SIZE << order) >> 20); + io_tlb_nslabs = SLABS_PER_PAGE << order; + } + rc = swiotlb_late_init_with_tbl(vstart, io_tlb_nslabs); + if (rc) + free_pages((unsigned long)vstart, order); + + return rc; +} + +int +swiotlb_late_init_with_tbl(char *tlb, unsigned long nslabs) +{ + unsigned long i, bytes; + unsigned char *v_overflow_buffer; + + bytes = nslabs << IO_TLB_SHIFT; + + io_tlb_nslabs = nslabs; + io_tlb_start = virt_to_phys(tlb); + io_tlb_end = io_tlb_start + bytes; + + set_memory_decrypted((unsigned long)tlb, bytes >> PAGE_SHIFT); + memset(tlb, 0, bytes); + + /* + * Get the overflow emergency buffer + */ + v_overflow_buffer = (void *)__get_free_pages(GFP_DMA, + get_order(io_tlb_overflow)); + if (!v_overflow_buffer) + goto cleanup2; + + set_memory_decrypted((unsigned long)v_overflow_buffer, + io_tlb_overflow >> PAGE_SHIFT); + memset(v_overflow_buffer, 0, io_tlb_overflow); + io_tlb_overflow_buffer = virt_to_phys(v_overflow_buffer); + + /* + * Allocate and initialize the free list array. This array is used + * to find contiguous free memory regions of size up to IO_TLB_SEGSIZE + * between io_tlb_start and io_tlb_end. + */ + io_tlb_list = (unsigned int *)__get_free_pages(GFP_KERNEL, + get_order(io_tlb_nslabs * sizeof(int))); + if (!io_tlb_list) + goto cleanup3; + + io_tlb_orig_addr = (phys_addr_t *) + __get_free_pages(GFP_KERNEL, + get_order(io_tlb_nslabs * + sizeof(phys_addr_t))); + if (!io_tlb_orig_addr) + goto cleanup4; + + for (i = 0; i < io_tlb_nslabs; i++) { + io_tlb_list[i] = IO_TLB_SEGSIZE - OFFSET(i, IO_TLB_SEGSIZE); + io_tlb_orig_addr[i] = INVALID_PHYS_ADDR; + } + io_tlb_index = 0; + + swiotlb_print_info(); + + late_alloc = 1; + + swiotlb_set_max_segment(io_tlb_nslabs << IO_TLB_SHIFT); + + return 0; + +cleanup4: + free_pages((unsigned long)io_tlb_list, get_order(io_tlb_nslabs * + sizeof(int))); + io_tlb_list = NULL; +cleanup3: + free_pages((unsigned long)v_overflow_buffer, + get_order(io_tlb_overflow)); + io_tlb_overflow_buffer = 0; +cleanup2: + io_tlb_end = 0; + io_tlb_start = 0; + io_tlb_nslabs = 0; + max_segment = 0; + return -ENOMEM; +} + +void __init swiotlb_exit(void) +{ + if (!io_tlb_orig_addr) + return; + + if (late_alloc) { + free_pages((unsigned long)phys_to_virt(io_tlb_overflow_buffer), + get_order(io_tlb_overflow)); + free_pages((unsigned long)io_tlb_orig_addr, + get_order(io_tlb_nslabs * sizeof(phys_addr_t))); + free_pages((unsigned long)io_tlb_list, get_order(io_tlb_nslabs * + sizeof(int))); + free_pages((unsigned long)phys_to_virt(io_tlb_start), + get_order(io_tlb_nslabs << IO_TLB_SHIFT)); + } else { + memblock_free_late(io_tlb_overflow_buffer, + PAGE_ALIGN(io_tlb_overflow)); + memblock_free_late(__pa(io_tlb_orig_addr), + PAGE_ALIGN(io_tlb_nslabs * sizeof(phys_addr_t))); + memblock_free_late(__pa(io_tlb_list), + PAGE_ALIGN(io_tlb_nslabs * sizeof(int))); + memblock_free_late(io_tlb_start, + PAGE_ALIGN(io_tlb_nslabs << IO_TLB_SHIFT)); + } + io_tlb_nslabs = 0; + max_segment = 0; +} + +int is_swiotlb_buffer(phys_addr_t paddr) +{ + return paddr >= io_tlb_start && paddr < io_tlb_end; +} + +/* + * Bounce: copy the swiotlb buffer back to the original dma location + */ +static void swiotlb_bounce(phys_addr_t orig_addr, phys_addr_t tlb_addr, + size_t size, enum dma_data_direction dir) +{ + unsigned long pfn = PFN_DOWN(orig_addr); + unsigned char *vaddr = phys_to_virt(tlb_addr); + + if (PageHighMem(pfn_to_page(pfn))) { + /* The buffer does not have a mapping. Map it in and copy */ + unsigned int offset = orig_addr & ~PAGE_MASK; + char *buffer; + unsigned int sz = 0; + unsigned long flags; + + while (size) { + sz = min_t(size_t, PAGE_SIZE - offset, size); + + local_irq_save(flags); + buffer = kmap_atomic(pfn_to_page(pfn)); + if (dir == DMA_TO_DEVICE) + memcpy(vaddr, buffer + offset, sz); + else + memcpy(buffer + offset, vaddr, sz); + kunmap_atomic(buffer); + local_irq_restore(flags); + + size -= sz; + pfn++; + vaddr += sz; + offset = 0; + } + } else if (dir == DMA_TO_DEVICE) { + memcpy(vaddr, phys_to_virt(orig_addr), size); + } else { + memcpy(phys_to_virt(orig_addr), vaddr, size); + } +} + +phys_addr_t swiotlb_tbl_map_single(struct device *hwdev, + dma_addr_t tbl_dma_addr, + phys_addr_t orig_addr, size_t size, + enum dma_data_direction dir, + unsigned long attrs) +{ + unsigned long flags; + phys_addr_t tlb_addr; + unsigned int nslots, stride, index, wrap; + int i; + unsigned long mask; + unsigned long offset_slots; + unsigned long max_slots; + + if (no_iotlb_memory) + panic("Can not allocate SWIOTLB buffer earlier and can't now provide you with the DMA bounce buffer"); + + if (mem_encrypt_active()) + pr_warn_once("%s is active and system is using DMA bounce buffers\n", + sme_active() ? "SME" : "SEV"); + + mask = dma_get_seg_boundary(hwdev); + + tbl_dma_addr &= mask; + + offset_slots = ALIGN(tbl_dma_addr, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT; + + /* + * Carefully handle integer overflow which can occur when mask == ~0UL. + */ + max_slots = mask + 1 + ? ALIGN(mask + 1, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT + : 1UL << (BITS_PER_LONG - IO_TLB_SHIFT); + + /* + * For mappings greater than or equal to a page, we limit the stride + * (and hence alignment) to a page size. + */ + nslots = ALIGN(size, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT; + if (size >= PAGE_SIZE) + stride = (1 << (PAGE_SHIFT - IO_TLB_SHIFT)); + else + stride = 1; + + BUG_ON(!nslots); + + /* + * Find suitable number of IO TLB entries size that will fit this + * request and allocate a buffer from that IO TLB pool. + */ + spin_lock_irqsave(&io_tlb_lock, flags); + index = ALIGN(io_tlb_index, stride); + if (index >= io_tlb_nslabs) + index = 0; + wrap = index; + + do { + while (iommu_is_span_boundary(index, nslots, offset_slots, + max_slots)) { + index += stride; + if (index >= io_tlb_nslabs) + index = 0; + if (index == wrap) + goto not_found; + } + + /* + * If we find a slot that indicates we have 'nslots' number of + * contiguous buffers, we allocate the buffers from that slot + * and mark the entries as '0' indicating unavailable. + */ + if (io_tlb_list[index] >= nslots) { + int count = 0; + + for (i = index; i < (int) (index + nslots); i++) + io_tlb_list[i] = 0; + for (i = index - 1; (OFFSET(i, IO_TLB_SEGSIZE) != IO_TLB_SEGSIZE - 1) && io_tlb_list[i]; i--) + io_tlb_list[i] = ++count; + tlb_addr = io_tlb_start + (index << IO_TLB_SHIFT); + + /* + * Update the indices to avoid searching in the next + * round. + */ + io_tlb_index = ((index + nslots) < io_tlb_nslabs + ? (index + nslots) : 0); + + goto found; + } + index += stride; + if (index >= io_tlb_nslabs) + index = 0; + } while (index != wrap); + +not_found: + spin_unlock_irqrestore(&io_tlb_lock, flags); + if (!(attrs & DMA_ATTR_NO_WARN) && printk_ratelimit()) + dev_warn(hwdev, "swiotlb buffer is full (sz: %zd bytes)\n", size); + return SWIOTLB_MAP_ERROR; +found: + spin_unlock_irqrestore(&io_tlb_lock, flags); + + /* + * Save away the mapping from the original address to the DMA address. + * This is needed when we sync the memory. Then we sync the buffer if + * needed. + */ + for (i = 0; i < nslots; i++) + io_tlb_orig_addr[index+i] = orig_addr + (i << IO_TLB_SHIFT); + if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC) && + (dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL)) + swiotlb_bounce(orig_addr, tlb_addr, size, DMA_TO_DEVICE); + + return tlb_addr; +} + +/* + * Allocates bounce buffer and returns its physical address. + */ +static phys_addr_t +map_single(struct device *hwdev, phys_addr_t phys, size_t size, + enum dma_data_direction dir, unsigned long attrs) +{ + dma_addr_t start_dma_addr; + + if (swiotlb_force == SWIOTLB_NO_FORCE) { + dev_warn_ratelimited(hwdev, "Cannot do DMA to address %pa\n", + &phys); + return SWIOTLB_MAP_ERROR; + } + + start_dma_addr = __phys_to_dma(hwdev, io_tlb_start); + return swiotlb_tbl_map_single(hwdev, start_dma_addr, phys, size, + dir, attrs); +} + +/* + * tlb_addr is the physical address of the bounce buffer to unmap. + */ +void swiotlb_tbl_unmap_single(struct device *hwdev, phys_addr_t tlb_addr, + size_t size, enum dma_data_direction dir, + unsigned long attrs) +{ + unsigned long flags; + int i, count, nslots = ALIGN(size, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT; + int index = (tlb_addr - io_tlb_start) >> IO_TLB_SHIFT; + phys_addr_t orig_addr = io_tlb_orig_addr[index]; + + /* + * First, sync the memory before unmapping the entry + */ + if (orig_addr != INVALID_PHYS_ADDR && + !(attrs & DMA_ATTR_SKIP_CPU_SYNC) && + ((dir == DMA_FROM_DEVICE) || (dir == DMA_BIDIRECTIONAL))) + swiotlb_bounce(orig_addr, tlb_addr, size, DMA_FROM_DEVICE); + + /* + * Return the buffer to the free list by setting the corresponding + * entries to indicate the number of contiguous entries available. + * While returning the entries to the free list, we merge the entries + * with slots below and above the pool being returned. + */ + spin_lock_irqsave(&io_tlb_lock, flags); + { + count = ((index + nslots) < ALIGN(index + 1, IO_TLB_SEGSIZE) ? + io_tlb_list[index + nslots] : 0); + /* + * Step 1: return the slots to the free list, merging the + * slots with superceeding slots + */ + for (i = index + nslots - 1; i >= index; i--) { + io_tlb_list[i] = ++count; + io_tlb_orig_addr[i] = INVALID_PHYS_ADDR; + } + /* + * Step 2: merge the returned slots with the preceding slots, + * if available (non zero) + */ + for (i = index - 1; (OFFSET(i, IO_TLB_SEGSIZE) != IO_TLB_SEGSIZE -1) && io_tlb_list[i]; i--) + io_tlb_list[i] = ++count; + } + spin_unlock_irqrestore(&io_tlb_lock, flags); +} + +void swiotlb_tbl_sync_single(struct device *hwdev, phys_addr_t tlb_addr, + size_t size, enum dma_data_direction dir, + enum dma_sync_target target) +{ + int index = (tlb_addr - io_tlb_start) >> IO_TLB_SHIFT; + phys_addr_t orig_addr = io_tlb_orig_addr[index]; + + if (orig_addr == INVALID_PHYS_ADDR) + return; + orig_addr += (unsigned long)tlb_addr & ((1 << IO_TLB_SHIFT) - 1); + + switch (target) { + case SYNC_FOR_CPU: + if (likely(dir == DMA_FROM_DEVICE || dir == DMA_BIDIRECTIONAL)) + swiotlb_bounce(orig_addr, tlb_addr, + size, DMA_FROM_DEVICE); + else + BUG_ON(dir != DMA_TO_DEVICE); + break; + case SYNC_FOR_DEVICE: + if (likely(dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL)) + swiotlb_bounce(orig_addr, tlb_addr, + size, DMA_TO_DEVICE); + else + BUG_ON(dir != DMA_FROM_DEVICE); + break; + default: + BUG(); + } +} + +static inline bool dma_coherent_ok(struct device *dev, dma_addr_t addr, + size_t size) +{ + u64 mask = DMA_BIT_MASK(32); + + if (dev && dev->coherent_dma_mask) + mask = dev->coherent_dma_mask; + return addr + size - 1 <= mask; +} + +static void * +swiotlb_alloc_buffer(struct device *dev, size_t size, dma_addr_t *dma_handle, + unsigned long attrs) +{ + phys_addr_t phys_addr; + + if (swiotlb_force == SWIOTLB_NO_FORCE) + goto out_warn; + + phys_addr = swiotlb_tbl_map_single(dev, + __phys_to_dma(dev, io_tlb_start), + 0, size, DMA_FROM_DEVICE, attrs); + if (phys_addr == SWIOTLB_MAP_ERROR) + goto out_warn; + + *dma_handle = __phys_to_dma(dev, phys_addr); + if (!dma_coherent_ok(dev, *dma_handle, size)) + goto out_unmap; + + memset(phys_to_virt(phys_addr), 0, size); + return phys_to_virt(phys_addr); + +out_unmap: + dev_warn(dev, "hwdev DMA mask = 0x%016Lx, dev_addr = 0x%016Lx\n", + (unsigned long long)dev->coherent_dma_mask, + (unsigned long long)*dma_handle); + + /* + * DMA_TO_DEVICE to avoid memcpy in unmap_single. + * DMA_ATTR_SKIP_CPU_SYNC is optional. + */ + swiotlb_tbl_unmap_single(dev, phys_addr, size, DMA_TO_DEVICE, + DMA_ATTR_SKIP_CPU_SYNC); +out_warn: + if (!(attrs & DMA_ATTR_NO_WARN) && printk_ratelimit()) { + dev_warn(dev, + "swiotlb: coherent allocation failed, size=%zu\n", + size); + dump_stack(); + } + return NULL; +} + +static bool swiotlb_free_buffer(struct device *dev, size_t size, + dma_addr_t dma_addr) +{ + phys_addr_t phys_addr = dma_to_phys(dev, dma_addr); + + WARN_ON_ONCE(irqs_disabled()); + + if (!is_swiotlb_buffer(phys_addr)) + return false; + + /* + * DMA_TO_DEVICE to avoid memcpy in swiotlb_tbl_unmap_single. + * DMA_ATTR_SKIP_CPU_SYNC is optional. + */ + swiotlb_tbl_unmap_single(dev, phys_addr, size, DMA_TO_DEVICE, + DMA_ATTR_SKIP_CPU_SYNC); + return true; +} + +static void +swiotlb_full(struct device *dev, size_t size, enum dma_data_direction dir, + int do_panic) +{ + if (swiotlb_force == SWIOTLB_NO_FORCE) + return; + + /* + * Ran out of IOMMU space for this operation. This is very bad. + * Unfortunately the drivers cannot handle this operation properly. + * unless they check for dma_mapping_error (most don't) + * When the mapping is small enough return a static buffer to limit + * the damage, or panic when the transfer is too big. + */ + dev_err_ratelimited(dev, "DMA: Out of SW-IOMMU space for %zu bytes\n", + size); + + if (size <= io_tlb_overflow || !do_panic) + return; + + if (dir == DMA_BIDIRECTIONAL) + panic("DMA: Random memory could be DMA accessed\n"); + if (dir == DMA_FROM_DEVICE) + panic("DMA: Random memory could be DMA written\n"); + if (dir == DMA_TO_DEVICE) + panic("DMA: Random memory could be DMA read\n"); +} + +/* + * Map a single buffer of the indicated size for DMA in streaming mode. The + * physical address to use is returned. + * + * Once the device is given the dma address, the device owns this memory until + * either swiotlb_unmap_page or swiotlb_dma_sync_single is performed. + */ +dma_addr_t swiotlb_map_page(struct device *dev, struct page *page, + unsigned long offset, size_t size, + enum dma_data_direction dir, + unsigned long attrs) +{ + phys_addr_t map, phys = page_to_phys(page) + offset; + dma_addr_t dev_addr = phys_to_dma(dev, phys); + + BUG_ON(dir == DMA_NONE); + /* + * If the address happens to be in the device's DMA window, + * we can safely return the device addr and not worry about bounce + * buffering it. + */ + if (dma_capable(dev, dev_addr, size) && swiotlb_force != SWIOTLB_FORCE) + return dev_addr; + + trace_swiotlb_bounced(dev, dev_addr, size, swiotlb_force); + + /* Oh well, have to allocate and map a bounce buffer. */ + map = map_single(dev, phys, size, dir, attrs); + if (map == SWIOTLB_MAP_ERROR) { + swiotlb_full(dev, size, dir, 1); + return __phys_to_dma(dev, io_tlb_overflow_buffer); + } + + dev_addr = __phys_to_dma(dev, map); + + /* Ensure that the address returned is DMA'ble */ + if (dma_capable(dev, dev_addr, size)) + return dev_addr; + + attrs |= DMA_ATTR_SKIP_CPU_SYNC; + swiotlb_tbl_unmap_single(dev, map, size, dir, attrs); + + return __phys_to_dma(dev, io_tlb_overflow_buffer); +} + +/* + * Unmap a single streaming mode DMA translation. The dma_addr and size must + * match what was provided for in a previous swiotlb_map_page call. All + * other usages are undefined. + * + * After this call, reads by the cpu to the buffer are guaranteed to see + * whatever the device wrote there. + */ +static void unmap_single(struct device *hwdev, dma_addr_t dev_addr, + size_t size, enum dma_data_direction dir, + unsigned long attrs) +{ + phys_addr_t paddr = dma_to_phys(hwdev, dev_addr); + + BUG_ON(dir == DMA_NONE); + + if (is_swiotlb_buffer(paddr)) { + swiotlb_tbl_unmap_single(hwdev, paddr, size, dir, attrs); + return; + } + + if (dir != DMA_FROM_DEVICE) + return; + + /* + * phys_to_virt doesn't work with hihgmem page but we could + * call dma_mark_clean() with hihgmem page here. However, we + * are fine since dma_mark_clean() is null on POWERPC. We can + * make dma_mark_clean() take a physical address if necessary. + */ + dma_mark_clean(phys_to_virt(paddr), size); +} + +void swiotlb_unmap_page(struct device *hwdev, dma_addr_t dev_addr, + size_t size, enum dma_data_direction dir, + unsigned long attrs) +{ + unmap_single(hwdev, dev_addr, size, dir, attrs); +} + +/* + * Make physical memory consistent for a single streaming mode DMA translation + * after a transfer. + * + * If you perform a swiotlb_map_page() but wish to interrogate the buffer + * using the cpu, yet do not wish to teardown the dma mapping, you must + * call this function before doing so. At the next point you give the dma + * address back to the card, you must first perform a + * swiotlb_dma_sync_for_device, and then the device again owns the buffer + */ +static void +swiotlb_sync_single(struct device *hwdev, dma_addr_t dev_addr, + size_t size, enum dma_data_direction dir, + enum dma_sync_target target) +{ + phys_addr_t paddr = dma_to_phys(hwdev, dev_addr); + + BUG_ON(dir == DMA_NONE); + + if (is_swiotlb_buffer(paddr)) { + swiotlb_tbl_sync_single(hwdev, paddr, size, dir, target); + return; + } + + if (dir != DMA_FROM_DEVICE) + return; + + dma_mark_clean(phys_to_virt(paddr), size); +} + +void +swiotlb_sync_single_for_cpu(struct device *hwdev, dma_addr_t dev_addr, + size_t size, enum dma_data_direction dir) +{ + swiotlb_sync_single(hwdev, dev_addr, size, dir, SYNC_FOR_CPU); +} + +void +swiotlb_sync_single_for_device(struct device *hwdev, dma_addr_t dev_addr, + size_t size, enum dma_data_direction dir) +{ + swiotlb_sync_single(hwdev, dev_addr, size, dir, SYNC_FOR_DEVICE); +} + +/* + * Map a set of buffers described by scatterlist in streaming mode for DMA. + * This is the scatter-gather version of the above swiotlb_map_page + * interface. Here the scatter gather list elements are each tagged with the + * appropriate dma address and length. They are obtained via + * sg_dma_{address,length}(SG). + * + * NOTE: An implementation may be able to use a smaller number of + * DMA address/length pairs than there are SG table elements. + * (for example via virtual mapping capabilities) + * The routine returns the number of addr/length pairs actually + * used, at most nents. + * + * Device ownership issues as mentioned above for swiotlb_map_page are the + * same here. + */ +int +swiotlb_map_sg_attrs(struct device *hwdev, struct scatterlist *sgl, int nelems, + enum dma_data_direction dir, unsigned long attrs) +{ + struct scatterlist *sg; + int i; + + BUG_ON(dir == DMA_NONE); + + for_each_sg(sgl, sg, nelems, i) { + phys_addr_t paddr = sg_phys(sg); + dma_addr_t dev_addr = phys_to_dma(hwdev, paddr); + + if (swiotlb_force == SWIOTLB_FORCE || + !dma_capable(hwdev, dev_addr, sg->length)) { + phys_addr_t map = map_single(hwdev, sg_phys(sg), + sg->length, dir, attrs); + if (map == SWIOTLB_MAP_ERROR) { + /* Don't panic here, we expect map_sg users + to do proper error handling. */ + swiotlb_full(hwdev, sg->length, dir, 0); + attrs |= DMA_ATTR_SKIP_CPU_SYNC; + swiotlb_unmap_sg_attrs(hwdev, sgl, i, dir, + attrs); + sg_dma_len(sgl) = 0; + return 0; + } + sg->dma_address = __phys_to_dma(hwdev, map); + } else + sg->dma_address = dev_addr; + sg_dma_len(sg) = sg->length; + } + return nelems; +} + +/* + * Unmap a set of streaming mode DMA translations. Again, cpu read rules + * concerning calls here are the same as for swiotlb_unmap_page() above. + */ +void +swiotlb_unmap_sg_attrs(struct device *hwdev, struct scatterlist *sgl, + int nelems, enum dma_data_direction dir, + unsigned long attrs) +{ + struct scatterlist *sg; + int i; + + BUG_ON(dir == DMA_NONE); + + for_each_sg(sgl, sg, nelems, i) + unmap_single(hwdev, sg->dma_address, sg_dma_len(sg), dir, + attrs); +} + +/* + * Make physical memory consistent for a set of streaming mode DMA translations + * after a transfer. + * + * The same as swiotlb_sync_single_* but for a scatter-gather list, same rules + * and usage. + */ +static void +swiotlb_sync_sg(struct device *hwdev, struct scatterlist *sgl, + int nelems, enum dma_data_direction dir, + enum dma_sync_target target) +{ + struct scatterlist *sg; + int i; + + for_each_sg(sgl, sg, nelems, i) + swiotlb_sync_single(hwdev, sg->dma_address, + sg_dma_len(sg), dir, target); +} + +void +swiotlb_sync_sg_for_cpu(struct device *hwdev, struct scatterlist *sg, + int nelems, enum dma_data_direction dir) +{ + swiotlb_sync_sg(hwdev, sg, nelems, dir, SYNC_FOR_CPU); +} + +void +swiotlb_sync_sg_for_device(struct device *hwdev, struct scatterlist *sg, + int nelems, enum dma_data_direction dir) +{ + swiotlb_sync_sg(hwdev, sg, nelems, dir, SYNC_FOR_DEVICE); +} + +int +swiotlb_dma_mapping_error(struct device *hwdev, dma_addr_t dma_addr) +{ + return (dma_addr == __phys_to_dma(hwdev, io_tlb_overflow_buffer)); +} + +/* + * Return whether the given device DMA address mask can be supported + * properly. For example, if your device can only drive the low 24-bits + * during bus mastering, then you would pass 0x00ffffff as the mask to + * this function. + */ +int +swiotlb_dma_supported(struct device *hwdev, u64 mask) +{ + return __phys_to_dma(hwdev, io_tlb_end - 1) <= mask; +} + +void *swiotlb_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle, + gfp_t gfp, unsigned long attrs) +{ + void *vaddr; + + /* temporary workaround: */ + if (gfp & __GFP_NOWARN) + attrs |= DMA_ATTR_NO_WARN; + + /* + * Don't print a warning when the first allocation attempt fails. + * swiotlb_alloc_coherent() will print a warning when the DMA memory + * allocation ultimately failed. + */ + gfp |= __GFP_NOWARN; + + vaddr = dma_direct_alloc(dev, size, dma_handle, gfp, attrs); + if (!vaddr) + vaddr = swiotlb_alloc_buffer(dev, size, dma_handle, attrs); + return vaddr; +} + +void swiotlb_free(struct device *dev, size_t size, void *vaddr, + dma_addr_t dma_addr, unsigned long attrs) +{ + if (!swiotlb_free_buffer(dev, size, dma_addr)) + dma_direct_free(dev, size, vaddr, dma_addr, attrs); +} + +const struct dma_map_ops swiotlb_dma_ops = { + .mapping_error = swiotlb_dma_mapping_error, + .alloc = swiotlb_alloc, + .free = swiotlb_free, + .sync_single_for_cpu = swiotlb_sync_single_for_cpu, + .sync_single_for_device = swiotlb_sync_single_for_device, + .sync_sg_for_cpu = swiotlb_sync_sg_for_cpu, + .sync_sg_for_device = swiotlb_sync_sg_for_device, + .map_sg = swiotlb_map_sg_attrs, + .unmap_sg = swiotlb_unmap_sg_attrs, + .map_page = swiotlb_map_page, + .unmap_page = swiotlb_unmap_page, + .dma_supported = dma_direct_supported, +}; diff --git a/kernel/dma/virt.c b/kernel/dma/virt.c new file mode 100644 index 000000000000..631ddec4b60a --- /dev/null +++ b/kernel/dma/virt.c @@ -0,0 +1,59 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * DMA operations that map to virtual addresses without flushing memory. + */ +#include +#include +#include +#include + +static void *dma_virt_alloc(struct device *dev, size_t size, + dma_addr_t *dma_handle, gfp_t gfp, + unsigned long attrs) +{ + void *ret; + + ret = (void *)__get_free_pages(gfp, get_order(size)); + if (ret) + *dma_handle = (uintptr_t)ret; + return ret; +} + +static void dma_virt_free(struct device *dev, size_t size, + void *cpu_addr, dma_addr_t dma_addr, + unsigned long attrs) +{ + free_pages((unsigned long)cpu_addr, get_order(size)); +} + +static dma_addr_t dma_virt_map_page(struct device *dev, struct page *page, + unsigned long offset, size_t size, + enum dma_data_direction dir, + unsigned long attrs) +{ + return (uintptr_t)(page_address(page) + offset); +} + +static int dma_virt_map_sg(struct device *dev, struct scatterlist *sgl, + int nents, enum dma_data_direction dir, + unsigned long attrs) +{ + int i; + struct scatterlist *sg; + + for_each_sg(sgl, sg, nents, i) { + BUG_ON(!sg_page(sg)); + sg_dma_address(sg) = (uintptr_t)sg_virt(sg); + sg_dma_len(sg) = sg->length; + } + + return nents; +} + +const struct dma_map_ops dma_virt_ops = { + .alloc = dma_virt_alloc, + .free = dma_virt_free, + .map_page = dma_virt_map_page, + .map_sg = dma_virt_map_sg, +}; +EXPORT_SYMBOL(dma_virt_ops); diff --git a/lib/Kconfig b/lib/Kconfig index 809fdd155739..803fcbced729 100644 --- a/lib/Kconfig +++ b/lib/Kconfig @@ -420,60 +420,15 @@ config HAS_IOPORT_MAP depends on HAS_IOMEM && !NO_IOPORT_MAP default y -config HAS_DMA - bool - depends on !NO_DMA - default y +source "kernel/dma/Kconfig" config SGL_ALLOC bool default n -config NEED_SG_DMA_LENGTH - bool - -config NEED_DMA_MAP_STATE - bool - -config ARCH_DMA_ADDR_T_64BIT - def_bool 64BIT || PHYS_ADDR_T_64BIT - config IOMMU_HELPER bool -config ARCH_HAS_SYNC_DMA_FOR_DEVICE - bool - -config ARCH_HAS_SYNC_DMA_FOR_CPU - bool - select NEED_DMA_MAP_STATE - -config DMA_DIRECT_OPS - bool - depends on HAS_DMA - -config DMA_NONCOHERENT_OPS - bool - depends on HAS_DMA - select DMA_DIRECT_OPS - -config DMA_NONCOHERENT_MMAP - bool - depends on DMA_NONCOHERENT_OPS - -config DMA_NONCOHERENT_CACHE_SYNC - bool - depends on DMA_NONCOHERENT_OPS - -config DMA_VIRT_OPS - bool - depends on HAS_DMA - -config SWIOTLB - bool - select DMA_DIRECT_OPS - select NEED_DMA_MAP_STATE - config CHECK_SIGNATURE bool diff --git a/lib/Makefile b/lib/Makefile index 5e0e160c9242..8153fdab287f 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -29,9 +29,6 @@ lib-y := ctype.o string.o vsprintf.o cmdline.o \ lib-$(CONFIG_PRINTK) += dump_stack.o lib-$(CONFIG_MMU) += ioremap.o lib-$(CONFIG_SMP) += cpumask.o -obj-$(CONFIG_DMA_DIRECT_OPS) += dma-direct.o -obj-$(CONFIG_DMA_NONCOHERENT_OPS) += dma-noncoherent.o -obj-$(CONFIG_DMA_VIRT_OPS) += dma-virt.o lib-y += kobject.o klist.o obj-y += lockref.o @@ -148,7 +145,6 @@ obj-$(CONFIG_SMP) += percpu_counter.o obj-$(CONFIG_AUDIT_GENERIC) += audit.o obj-$(CONFIG_AUDIT_COMPAT_GENERIC) += compat_audit.o -obj-$(CONFIG_SWIOTLB) += swiotlb.o obj-$(CONFIG_IOMMU_HELPER) += iommu-helper.o obj-$(CONFIG_FAULT_INJECTION) += fault-inject.o obj-$(CONFIG_NOTIFIER_ERROR_INJECTION) += notifier-error-inject.o @@ -169,8 +165,6 @@ obj-$(CONFIG_NLATTR) += nlattr.o obj-$(CONFIG_LRU_CACHE) += lru_cache.o -obj-$(CONFIG_DMA_API_DEBUG) += dma-debug.o - obj-$(CONFIG_GENERIC_CSUM) += checksum.o obj-$(CONFIG_GENERIC_ATOMIC64) += atomic64.o diff --git a/lib/dma-debug.c b/lib/dma-debug.c deleted file mode 100644 index c007d25bee09..000000000000 --- a/lib/dma-debug.c +++ /dev/null @@ -1,1773 +0,0 @@ -/* - * Copyright (C) 2008 Advanced Micro Devices, Inc. - * - * Author: Joerg Roedel - * - * This program is free software; you can redistribute it and/or modify it - * under the terms of the GNU General Public License version 2 as published - * by the Free Software Foundation. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA - */ - -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include - -#include - -#define HASH_SIZE 1024ULL -#define HASH_FN_SHIFT 13 -#define HASH_FN_MASK (HASH_SIZE - 1) - -/* allow architectures to override this if absolutely required */ -#ifndef PREALLOC_DMA_DEBUG_ENTRIES -#define PREALLOC_DMA_DEBUG_ENTRIES (1 << 16) -#endif - -enum { - dma_debug_single, - dma_debug_page, - dma_debug_sg, - dma_debug_coherent, - dma_debug_resource, -}; - -enum map_err_types { - MAP_ERR_CHECK_NOT_APPLICABLE, - MAP_ERR_NOT_CHECKED, - MAP_ERR_CHECKED, -}; - -#define DMA_DEBUG_STACKTRACE_ENTRIES 5 - -/** - * struct dma_debug_entry - track a dma_map* or dma_alloc_coherent mapping - * @list: node on pre-allocated free_entries list - * @dev: 'dev' argument to dma_map_{page|single|sg} or dma_alloc_coherent - * @type: single, page, sg, coherent - * @pfn: page frame of the start address - * @offset: offset of mapping relative to pfn - * @size: length of the mapping - * @direction: enum dma_data_direction - * @sg_call_ents: 'nents' from dma_map_sg - * @sg_mapped_ents: 'mapped_ents' from dma_map_sg - * @map_err_type: track whether dma_mapping_error() was checked - * @stacktrace: support backtraces when a violation is detected - */ -struct dma_debug_entry { - struct list_head list; - struct device *dev; - int type; - unsigned long pfn; - size_t offset; - u64 dev_addr; - u64 size; - int direction; - int sg_call_ents; - int sg_mapped_ents; - enum map_err_types map_err_type; -#ifdef CONFIG_STACKTRACE - struct stack_trace stacktrace; - unsigned long st_entries[DMA_DEBUG_STACKTRACE_ENTRIES]; -#endif -}; - -typedef bool (*match_fn)(struct dma_debug_entry *, struct dma_debug_entry *); - -struct hash_bucket { - struct list_head list; - spinlock_t lock; -} ____cacheline_aligned_in_smp; - -/* Hash list to save the allocated dma addresses */ -static struct hash_bucket dma_entry_hash[HASH_SIZE]; -/* List of pre-allocated dma_debug_entry's */ -static LIST_HEAD(free_entries); -/* Lock for the list above */ -static DEFINE_SPINLOCK(free_entries_lock); - -/* Global disable flag - will be set in case of an error */ -static bool global_disable __read_mostly; - -/* Early initialization disable flag, set at the end of dma_debug_init */ -static bool dma_debug_initialized __read_mostly; - -static inline bool dma_debug_disabled(void) -{ - return global_disable || !dma_debug_initialized; -} - -/* Global error count */ -static u32 error_count; - -/* Global error show enable*/ -static u32 show_all_errors __read_mostly; -/* Number of errors to show */ -static u32 show_num_errors = 1; - -static u32 num_free_entries; -static u32 min_free_entries; -static u32 nr_total_entries; - -/* number of preallocated entries requested by kernel cmdline */ -static u32 nr_prealloc_entries = PREALLOC_DMA_DEBUG_ENTRIES; - -/* debugfs dentry's for the stuff above */ -static struct dentry *dma_debug_dent __read_mostly; -static struct dentry *global_disable_dent __read_mostly; -static struct dentry *error_count_dent __read_mostly; -static struct dentry *show_all_errors_dent __read_mostly; -static struct dentry *show_num_errors_dent __read_mostly; -static struct dentry *num_free_entries_dent __read_mostly; -static struct dentry *min_free_entries_dent __read_mostly; -static struct dentry *filter_dent __read_mostly; - -/* per-driver filter related state */ - -#define NAME_MAX_LEN 64 - -static char current_driver_name[NAME_MAX_LEN] __read_mostly; -static struct device_driver *current_driver __read_mostly; - -static DEFINE_RWLOCK(driver_name_lock); - -static const char *const maperr2str[] = { - [MAP_ERR_CHECK_NOT_APPLICABLE] = "dma map error check not applicable", - [MAP_ERR_NOT_CHECKED] = "dma map error not checked", - [MAP_ERR_CHECKED] = "dma map error checked", -}; - -static const char *type2name[5] = { "single", "page", - "scather-gather", "coherent", - "resource" }; - -static const char *dir2name[4] = { "DMA_BIDIRECTIONAL", "DMA_TO_DEVICE", - "DMA_FROM_DEVICE", "DMA_NONE" }; - -/* - * The access to some variables in this macro is racy. We can't use atomic_t - * here because all these variables are exported to debugfs. Some of them even - * writeable. This is also the reason why a lock won't help much. But anyway, - * the races are no big deal. Here is why: - * - * error_count: the addition is racy, but the worst thing that can happen is - * that we don't count some errors - * show_num_errors: the subtraction is racy. Also no big deal because in - * worst case this will result in one warning more in the - * system log than the user configured. This variable is - * writeable via debugfs. - */ -static inline void dump_entry_trace(struct dma_debug_entry *entry) -{ -#ifdef CONFIG_STACKTRACE - if (entry) { - pr_warning("Mapped at:\n"); - print_stack_trace(&entry->stacktrace, 0); - } -#endif -} - -static bool driver_filter(struct device *dev) -{ - struct device_driver *drv; - unsigned long flags; - bool ret; - - /* driver filter off */ - if (likely(!current_driver_name[0])) - return true; - - /* driver filter on and initialized */ - if (current_driver && dev && dev->driver == current_driver) - return true; - - /* driver filter on, but we can't filter on a NULL device... */ - if (!dev) - return false; - - if (current_driver || !current_driver_name[0]) - return false; - - /* driver filter on but not yet initialized */ - drv = dev->driver; - if (!drv) - return false; - - /* lock to protect against change of current_driver_name */ - read_lock_irqsave(&driver_name_lock, flags); - - ret = false; - if (drv->name && - strncmp(current_driver_name, drv->name, NAME_MAX_LEN - 1) == 0) { - current_driver = drv; - ret = true; - } - - read_unlock_irqrestore(&driver_name_lock, flags); - - return ret; -} - -#define err_printk(dev, entry, format, arg...) do { \ - error_count += 1; \ - if (driver_filter(dev) && \ - (show_all_errors || show_num_errors > 0)) { \ - WARN(1, "%s %s: " format, \ - dev ? dev_driver_string(dev) : "NULL", \ - dev ? dev_name(dev) : "NULL", ## arg); \ - dump_entry_trace(entry); \ - } \ - if (!show_all_errors && show_num_errors > 0) \ - show_num_errors -= 1; \ - } while (0); - -/* - * Hash related functions - * - * Every DMA-API request is saved into a struct dma_debug_entry. To - * have quick access to these structs they are stored into a hash. - */ -static int hash_fn(struct dma_debug_entry *entry) -{ - /* - * Hash function is based on the dma address. - * We use bits 20-27 here as the index into the hash - */ - return (entry->dev_addr >> HASH_FN_SHIFT) & HASH_FN_MASK; -} - -/* - * Request exclusive access to a hash bucket for a given dma_debug_entry. - */ -static struct hash_bucket *get_hash_bucket(struct dma_debug_entry *entry, - unsigned long *flags) - __acquires(&dma_entry_hash[idx].lock) -{ - int idx = hash_fn(entry); - unsigned long __flags; - - spin_lock_irqsave(&dma_entry_hash[idx].lock, __flags); - *flags = __flags; - return &dma_entry_hash[idx]; -} - -/* - * Give up exclusive access to the hash bucket - */ -static void put_hash_bucket(struct hash_bucket *bucket, - unsigned long *flags) - __releases(&bucket->lock) -{ - unsigned long __flags = *flags; - - spin_unlock_irqrestore(&bucket->lock, __flags); -} - -static bool exact_match(struct dma_debug_entry *a, struct dma_debug_entry *b) -{ - return ((a->dev_addr == b->dev_addr) && - (a->dev == b->dev)) ? true : false; -} - -static bool containing_match(struct dma_debug_entry *a, - struct dma_debug_entry *b) -{ - if (a->dev != b->dev) - return false; - - if ((b->dev_addr <= a->dev_addr) && - ((b->dev_addr + b->size) >= (a->dev_addr + a->size))) - return true; - - return false; -} - -/* - * Search a given entry in the hash bucket list - */ -static struct dma_debug_entry *__hash_bucket_find(struct hash_bucket *bucket, - struct dma_debug_entry *ref, - match_fn match) -{ - struct dma_debug_entry *entry, *ret = NULL; - int matches = 0, match_lvl, last_lvl = -1; - - list_for_each_entry(entry, &bucket->list, list) { - if (!match(ref, entry)) - continue; - - /* - * Some drivers map the same physical address multiple - * times. Without a hardware IOMMU this results in the - * same device addresses being put into the dma-debug - * hash multiple times too. This can result in false - * positives being reported. Therefore we implement a - * best-fit algorithm here which returns the entry from - * the hash which fits best to the reference value - * instead of the first-fit. - */ - matches += 1; - match_lvl = 0; - entry->size == ref->size ? ++match_lvl : 0; - entry->type == ref->type ? ++match_lvl : 0; - entry->direction == ref->direction ? ++match_lvl : 0; - entry->sg_call_ents == ref->sg_call_ents ? ++match_lvl : 0; - - if (match_lvl == 4) { - /* perfect-fit - return the result */ - return entry; - } else if (match_lvl > last_lvl) { - /* - * We found an entry that fits better then the - * previous one or it is the 1st match. - */ - last_lvl = match_lvl; - ret = entry; - } - } - - /* - * If we have multiple matches but no perfect-fit, just return - * NULL. - */ - ret = (matches == 1) ? ret : NULL; - - return ret; -} - -static struct dma_debug_entry *bucket_find_exact(struct hash_bucket *bucket, - struct dma_debug_entry *ref) -{ - return __hash_bucket_find(bucket, ref, exact_match); -} - -static struct dma_debug_entry *bucket_find_contain(struct hash_bucket **bucket, - struct dma_debug_entry *ref, - unsigned long *flags) -{ - - unsigned int max_range = dma_get_max_seg_size(ref->dev); - struct dma_debug_entry *entry, index = *ref; - unsigned int range = 0; - - while (range <= max_range) { - entry = __hash_bucket_find(*bucket, ref, containing_match); - - if (entry) - return entry; - - /* - * Nothing found, go back a hash bucket - */ - put_hash_bucket(*bucket, flags); - range += (1 << HASH_FN_SHIFT); - index.dev_addr -= (1 << HASH_FN_SHIFT); - *bucket = get_hash_bucket(&index, flags); - } - - return NULL; -} - -/* - * Add an entry to a hash bucket - */ -static void hash_bucket_add(struct hash_bucket *bucket, - struct dma_debug_entry *entry) -{ - list_add_tail(&entry->list, &bucket->list); -} - -/* - * Remove entry from a hash bucket list - */ -static void hash_bucket_del(struct dma_debug_entry *entry) -{ - list_del(&entry->list); -} - -static unsigned long long phys_addr(struct dma_debug_entry *entry) -{ - if (entry->type == dma_debug_resource) - return __pfn_to_phys(entry->pfn) + entry->offset; - - return page_to_phys(pfn_to_page(entry->pfn)) + entry->offset; -} - -/* - * Dump mapping entries for debugging purposes - */ -void debug_dma_dump_mappings(struct device *dev) -{ - int idx; - - for (idx = 0; idx < HASH_SIZE; idx++) { - struct hash_bucket *bucket = &dma_entry_hash[idx]; - struct dma_debug_entry *entry; - unsigned long flags; - - spin_lock_irqsave(&bucket->lock, flags); - - list_for_each_entry(entry, &bucket->list, list) { - if (!dev || dev == entry->dev) { - dev_info(entry->dev, - "%s idx %d P=%Lx N=%lx D=%Lx L=%Lx %s %s\n", - type2name[entry->type], idx, - phys_addr(entry), entry->pfn, - entry->dev_addr, entry->size, - dir2name[entry->direction], - maperr2str[entry->map_err_type]); - } - } - - spin_unlock_irqrestore(&bucket->lock, flags); - } -} - -/* - * For each mapping (initial cacheline in the case of - * dma_alloc_coherent/dma_map_page, initial cacheline in each page of a - * scatterlist, or the cacheline specified in dma_map_single) insert - * into this tree using the cacheline as the key. At - * dma_unmap_{single|sg|page} or dma_free_coherent delete the entry. If - * the entry already exists at insertion time add a tag as a reference - * count for the overlapping mappings. For now, the overlap tracking - * just ensures that 'unmaps' balance 'maps' before marking the - * cacheline idle, but we should also be flagging overlaps as an API - * violation. - * - * Memory usage is mostly constrained by the maximum number of available - * dma-debug entries in that we need a free dma_debug_entry before - * inserting into the tree. In the case of dma_map_page and - * dma_alloc_coherent there is only one dma_debug_entry and one - * dma_active_cacheline entry to track per event. dma_map_sg(), on the - * other hand, consumes a single dma_debug_entry, but inserts 'nents' - * entries into the tree. - * - * At any time debug_dma_assert_idle() can be called to trigger a - * warning if any cachelines in the given page are in the active set. - */ -static RADIX_TREE(dma_active_cacheline, GFP_NOWAIT); -static DEFINE_SPINLOCK(radix_lock); -#define ACTIVE_CACHELINE_MAX_OVERLAP ((1 << RADIX_TREE_MAX_TAGS) - 1) -#define CACHELINE_PER_PAGE_SHIFT (PAGE_SHIFT - L1_CACHE_SHIFT) -#define CACHELINES_PER_PAGE (1 << CACHELINE_PER_PAGE_SHIFT) - -static phys_addr_t to_cacheline_number(struct dma_debug_entry *entry) -{ - return (entry->pfn << CACHELINE_PER_PAGE_SHIFT) + - (entry->offset >> L1_CACHE_SHIFT); -} - -static int active_cacheline_read_overlap(phys_addr_t cln) -{ - int overlap = 0, i; - - for (i = RADIX_TREE_MAX_TAGS - 1; i >= 0; i--) - if (radix_tree_tag_get(&dma_active_cacheline, cln, i)) - overlap |= 1 << i; - return overlap; -} - -static int active_cacheline_set_overlap(phys_addr_t cln, int overlap) -{ - int i; - - if (overlap > ACTIVE_CACHELINE_MAX_OVERLAP || overlap < 0) - return overlap; - - for (i = RADIX_TREE_MAX_TAGS - 1; i >= 0; i--) - if (overlap & 1 << i) - radix_tree_tag_set(&dma_active_cacheline, cln, i); - else - radix_tree_tag_clear(&dma_active_cacheline, cln, i); - - return overlap; -} - -static void active_cacheline_inc_overlap(phys_addr_t cln) -{ - int overlap = active_cacheline_read_overlap(cln); - - overlap = active_cacheline_set_overlap(cln, ++overlap); - - /* If we overflowed the overlap counter then we're potentially - * leaking dma-mappings. Otherwise, if maps and unmaps are - * balanced then this overflow may cause false negatives in - * debug_dma_assert_idle() as the cacheline may be marked idle - * prematurely. - */ - WARN_ONCE(overlap > ACTIVE_CACHELINE_MAX_OVERLAP, - "DMA-API: exceeded %d overlapping mappings of cacheline %pa\n", - ACTIVE_CACHELINE_MAX_OVERLAP, &cln); -} - -static int active_cacheline_dec_overlap(phys_addr_t cln) -{ - int overlap = active_cacheline_read_overlap(cln); - - return active_cacheline_set_overlap(cln, --overlap); -} - -static int active_cacheline_insert(struct dma_debug_entry *entry) -{ - phys_addr_t cln = to_cacheline_number(entry); - unsigned long flags; - int rc; - - /* If the device is not writing memory then we don't have any - * concerns about the cpu consuming stale data. This mitigates - * legitimate usages of overlapping mappings. - */ - if (entry->direction == DMA_TO_DEVICE) - return 0; - - spin_lock_irqsave(&radix_lock, flags); - rc = radix_tree_insert(&dma_active_cacheline, cln, entry); - if (rc == -EEXIST) - active_cacheline_inc_overlap(cln); - spin_unlock_irqrestore(&radix_lock, flags); - - return rc; -} - -static void active_cacheline_remove(struct dma_debug_entry *entry) -{ - phys_addr_t cln = to_cacheline_number(entry); - unsigned long flags; - - /* ...mirror the insert case */ - if (entry->direction == DMA_TO_DEVICE) - return; - - spin_lock_irqsave(&radix_lock, flags); - /* since we are counting overlaps the final put of the - * cacheline will occur when the overlap count is 0. - * active_cacheline_dec_overlap() returns -1 in that case - */ - if (active_cacheline_dec_overlap(cln) < 0) - radix_tree_delete(&dma_active_cacheline, cln); - spin_unlock_irqrestore(&radix_lock, flags); -} - -/** - * debug_dma_assert_idle() - assert that a page is not undergoing dma - * @page: page to lookup in the dma_active_cacheline tree - * - * Place a call to this routine in cases where the cpu touching the page - * before the dma completes (page is dma_unmapped) will lead to data - * corruption. - */ -void debug_dma_assert_idle(struct page *page) -{ - static struct dma_debug_entry *ents[CACHELINES_PER_PAGE]; - struct dma_debug_entry *entry = NULL; - void **results = (void **) &ents; - unsigned int nents, i; - unsigned long flags; - phys_addr_t cln; - - if (dma_debug_disabled()) - return; - - if (!page) - return; - - cln = (phys_addr_t) page_to_pfn(page) << CACHELINE_PER_PAGE_SHIFT; - spin_lock_irqsave(&radix_lock, flags); - nents = radix_tree_gang_lookup(&dma_active_cacheline, results, cln, - CACHELINES_PER_PAGE); - for (i = 0; i < nents; i++) { - phys_addr_t ent_cln = to_cacheline_number(ents[i]); - - if (ent_cln == cln) { - entry = ents[i]; - break; - } else if (ent_cln >= cln + CACHELINES_PER_PAGE) - break; - } - spin_unlock_irqrestore(&radix_lock, flags); - - if (!entry) - return; - - cln = to_cacheline_number(entry); - err_printk(entry->dev, entry, - "DMA-API: cpu touching an active dma mapped cacheline [cln=%pa]\n", - &cln); -} - -/* - * Wrapper function for adding an entry to the hash. - * This function takes care of locking itself. - */ -static void add_dma_entry(struct dma_debug_entry *entry) -{ - struct hash_bucket *bucket; - unsigned long flags; - int rc; - - bucket = get_hash_bucket(entry, &flags); - hash_bucket_add(bucket, entry); - put_hash_bucket(bucket, &flags); - - rc = active_cacheline_insert(entry); - if (rc == -ENOMEM) { - pr_err("DMA-API: cacheline tracking ENOMEM, dma-debug disabled\n"); - global_disable = true; - } - - /* TODO: report -EEXIST errors here as overlapping mappings are - * not supported by the DMA API - */ -} - -static struct dma_debug_entry *__dma_entry_alloc(void) -{ - struct dma_debug_entry *entry; - - entry = list_entry(free_entries.next, struct dma_debug_entry, list); - list_del(&entry->list); - memset(entry, 0, sizeof(*entry)); - - num_free_entries -= 1; - if (num_free_entries < min_free_entries) - min_free_entries = num_free_entries; - - return entry; -} - -/* struct dma_entry allocator - * - * The next two functions implement the allocator for - * struct dma_debug_entries. - */ -static struct dma_debug_entry *dma_entry_alloc(void) -{ - struct dma_debug_entry *entry; - unsigned long flags; - - spin_lock_irqsave(&free_entries_lock, flags); - - if (list_empty(&free_entries)) { - global_disable = true; - spin_unlock_irqrestore(&free_entries_lock, flags); - pr_err("DMA-API: debugging out of memory - disabling\n"); - return NULL; - } - - entry = __dma_entry_alloc(); - - spin_unlock_irqrestore(&free_entries_lock, flags); - -#ifdef CONFIG_STACKTRACE - entry->stacktrace.max_entries = DMA_DEBUG_STACKTRACE_ENTRIES; - entry->stacktrace.entries = entry->st_entries; - entry->stacktrace.skip = 2; - save_stack_trace(&entry->stacktrace); -#endif - - return entry; -} - -static void dma_entry_free(struct dma_debug_entry *entry) -{ - unsigned long flags; - - active_cacheline_remove(entry); - - /* - * add to beginning of the list - this way the entries are - * more likely cache hot when they are reallocated. - */ - spin_lock_irqsave(&free_entries_lock, flags); - list_add(&entry->list, &free_entries); - num_free_entries += 1; - spin_unlock_irqrestore(&free_entries_lock, flags); -} - -int dma_debug_resize_entries(u32 num_entries) -{ - int i, delta, ret = 0; - unsigned long flags; - struct dma_debug_entry *entry; - LIST_HEAD(tmp); - - spin_lock_irqsave(&free_entries_lock, flags); - - if (nr_total_entries < num_entries) { - delta = num_entries - nr_total_entries; - - spin_unlock_irqrestore(&free_entries_lock, flags); - - for (i = 0; i < delta; i++) { - entry = kzalloc(sizeof(*entry), GFP_KERNEL); - if (!entry) - break; - - list_add_tail(&entry->list, &tmp); - } - - spin_lock_irqsave(&free_entries_lock, flags); - - list_splice(&tmp, &free_entries); - nr_total_entries += i; - num_free_entries += i; - } else { - delta = nr_total_entries - num_entries; - - for (i = 0; i < delta && !list_empty(&free_entries); i++) { - entry = __dma_entry_alloc(); - kfree(entry); - } - - nr_total_entries -= i; - } - - if (nr_total_entries != num_entries) - ret = 1; - - spin_unlock_irqrestore(&free_entries_lock, flags); - - return ret; -} - -/* - * DMA-API debugging init code - * - * The init code does two things: - * 1. Initialize core data structures - * 2. Preallocate a given number of dma_debug_entry structs - */ - -static int prealloc_memory(u32 num_entries) -{ - struct dma_debug_entry *entry, *next_entry; - int i; - - for (i = 0; i < num_entries; ++i) { - entry = kzalloc(sizeof(*entry), GFP_KERNEL); - if (!entry) - goto out_err; - - list_add_tail(&entry->list, &free_entries); - } - - num_free_entries = num_entries; - min_free_entries = num_entries; - - pr_info("DMA-API: preallocated %d debug entries\n", num_entries); - - return 0; - -out_err: - - list_for_each_entry_safe(entry, next_entry, &free_entries, list) { - list_del(&entry->list); - kfree(entry); - } - - return -ENOMEM; -} - -static ssize_t filter_read(struct file *file, char __user *user_buf, - size_t count, loff_t *ppos) -{ - char buf[NAME_MAX_LEN + 1]; - unsigned long flags; - int len; - - if (!current_driver_name[0]) - return 0; - - /* - * We can't copy to userspace directly because current_driver_name can - * only be read under the driver_name_lock with irqs disabled. So - * create a temporary copy first. - */ - read_lock_irqsave(&driver_name_lock, flags); - len = scnprintf(buf, NAME_MAX_LEN + 1, "%s\n", current_driver_name); - read_unlock_irqrestore(&driver_name_lock, flags); - - return simple_read_from_buffer(user_buf, count, ppos, buf, len); -} - -static ssize_t filter_write(struct file *file, const char __user *userbuf, - size_t count, loff_t *ppos) -{ - char buf[NAME_MAX_LEN]; - unsigned long flags; - size_t len; - int i; - - /* - * We can't copy from userspace directly. Access to - * current_driver_name is protected with a write_lock with irqs - * disabled. Since copy_from_user can fault and may sleep we - * need to copy to temporary buffer first - */ - len = min(count, (size_t)(NAME_MAX_LEN - 1)); - if (copy_from_user(buf, userbuf, len)) - return -EFAULT; - - buf[len] = 0; - - write_lock_irqsave(&driver_name_lock, flags); - - /* - * Now handle the string we got from userspace very carefully. - * The rules are: - * - only use the first token we got - * - token delimiter is everything looking like a space - * character (' ', '\n', '\t' ...) - * - */ - if (!isalnum(buf[0])) { - /* - * If the first character userspace gave us is not - * alphanumerical then assume the filter should be - * switched off. - */ - if (current_driver_name[0]) - pr_info("DMA-API: switching off dma-debug driver filter\n"); - current_driver_name[0] = 0; - current_driver = NULL; - goto out_unlock; - } - - /* - * Now parse out the first token and use it as the name for the - * driver to filter for. - */ - for (i = 0; i < NAME_MAX_LEN - 1; ++i) { - current_driver_name[i] = buf[i]; - if (isspace(buf[i]) || buf[i] == ' ' || buf[i] == 0) - break; - } - current_driver_name[i] = 0; - current_driver = NULL; - - pr_info("DMA-API: enable driver filter for driver [%s]\n", - current_driver_name); - -out_unlock: - write_unlock_irqrestore(&driver_name_lock, flags); - - return count; -} - -static const struct file_operations filter_fops = { - .read = filter_read, - .write = filter_write, - .llseek = default_llseek, -}; - -static int dma_debug_fs_init(void) -{ - dma_debug_dent = debugfs_create_dir("dma-api", NULL); - if (!dma_debug_dent) { - pr_err("DMA-API: can not create debugfs directory\n"); - return -ENOMEM; - } - - global_disable_dent = debugfs_create_bool("disabled", 0444, - dma_debug_dent, - &global_disable); - if (!global_disable_dent) - goto out_err; - - error_count_dent = debugfs_create_u32("error_count", 0444, - dma_debug_dent, &error_count); - if (!error_count_dent) - goto out_err; - - show_all_errors_dent = debugfs_create_u32("all_errors", 0644, - dma_debug_dent, - &show_all_errors); - if (!show_all_errors_dent) - goto out_err; - - show_num_errors_dent = debugfs_create_u32("num_errors", 0644, - dma_debug_dent, - &show_num_errors); - if (!show_num_errors_dent) - goto out_err; - - num_free_entries_dent = debugfs_create_u32("num_free_entries", 0444, - dma_debug_dent, - &num_free_entries); - if (!num_free_entries_dent) - goto out_err; - - min_free_entries_dent = debugfs_create_u32("min_free_entries", 0444, - dma_debug_dent, - &min_free_entries); - if (!min_free_entries_dent) - goto out_err; - - filter_dent = debugfs_create_file("driver_filter", 0644, - dma_debug_dent, NULL, &filter_fops); - if (!filter_dent) - goto out_err; - - return 0; - -out_err: - debugfs_remove_recursive(dma_debug_dent); - - return -ENOMEM; -} - -static int device_dma_allocations(struct device *dev, struct dma_debug_entry **out_entry) -{ - struct dma_debug_entry *entry; - unsigned long flags; - int count = 0, i; - - for (i = 0; i < HASH_SIZE; ++i) { - spin_lock_irqsave(&dma_entry_hash[i].lock, flags); - list_for_each_entry(entry, &dma_entry_hash[i].list, list) { - if (entry->dev == dev) { - count += 1; - *out_entry = entry; - } - } - spin_unlock_irqrestore(&dma_entry_hash[i].lock, flags); - } - - return count; -} - -static int dma_debug_device_change(struct notifier_block *nb, unsigned long action, void *data) -{ - struct device *dev = data; - struct dma_debug_entry *uninitialized_var(entry); - int count; - - if (dma_debug_disabled()) - return 0; - - switch (action) { - case BUS_NOTIFY_UNBOUND_DRIVER: - count = device_dma_allocations(dev, &entry); - if (count == 0) - break; - err_printk(dev, entry, "DMA-API: device driver has pending " - "DMA allocations while released from device " - "[count=%d]\n" - "One of leaked entries details: " - "[device address=0x%016llx] [size=%llu bytes] " - "[mapped with %s] [mapped as %s]\n", - count, entry->dev_addr, entry->size, - dir2name[entry->direction], type2name[entry->type]); - break; - default: - break; - } - - return 0; -} - -void dma_debug_add_bus(struct bus_type *bus) -{ - struct notifier_block *nb; - - if (dma_debug_disabled()) - return; - - nb = kzalloc(sizeof(struct notifier_block), GFP_KERNEL); - if (nb == NULL) { - pr_err("dma_debug_add_bus: out of memory\n"); - return; - } - - nb->notifier_call = dma_debug_device_change; - - bus_register_notifier(bus, nb); -} - -static int dma_debug_init(void) -{ - int i; - - /* Do not use dma_debug_initialized here, since we really want to be - * called to set dma_debug_initialized - */ - if (global_disable) - return 0; - - for (i = 0; i < HASH_SIZE; ++i) { - INIT_LIST_HEAD(&dma_entry_hash[i].list); - spin_lock_init(&dma_entry_hash[i].lock); - } - - if (dma_debug_fs_init() != 0) { - pr_err("DMA-API: error creating debugfs entries - disabling\n"); - global_disable = true; - - return 0; - } - - if (prealloc_memory(nr_prealloc_entries) != 0) { - pr_err("DMA-API: debugging out of memory error - disabled\n"); - global_disable = true; - - return 0; - } - - nr_total_entries = num_free_entries; - - dma_debug_initialized = true; - - pr_info("DMA-API: debugging enabled by kernel config\n"); - return 0; -} -core_initcall(dma_debug_init); - -static __init int dma_debug_cmdline(char *str) -{ - if (!str) - return -EINVAL; - - if (strncmp(str, "off", 3) == 0) { - pr_info("DMA-API: debugging disabled on kernel command line\n"); - global_disable = true; - } - - return 0; -} - -static __init int dma_debug_entries_cmdline(char *str) -{ - if (!str) - return -EINVAL; - if (!get_option(&str, &nr_prealloc_entries)) - nr_prealloc_entries = PREALLOC_DMA_DEBUG_ENTRIES; - return 0; -} - -__setup("dma_debug=", dma_debug_cmdline); -__setup("dma_debug_entries=", dma_debug_entries_cmdline); - -static void check_unmap(struct dma_debug_entry *ref) -{ - struct dma_debug_entry *entry; - struct hash_bucket *bucket; - unsigned long flags; - - bucket = get_hash_bucket(ref, &flags); - entry = bucket_find_exact(bucket, ref); - - if (!entry) { - /* must drop lock before calling dma_mapping_error */ - put_hash_bucket(bucket, &flags); - - if (dma_mapping_error(ref->dev, ref->dev_addr)) { - err_printk(ref->dev, NULL, - "DMA-API: device driver tries to free an " - "invalid DMA memory address\n"); - } else { - err_printk(ref->dev, NULL, - "DMA-API: device driver tries to free DMA " - "memory it has not allocated [device " - "address=0x%016llx] [size=%llu bytes]\n", - ref->dev_addr, ref->size); - } - return; - } - - if (ref->size != entry->size) { - err_printk(ref->dev, entry, "DMA-API: device driver frees " - "DMA memory with different size " - "[device address=0x%016llx] [map size=%llu bytes] " - "[unmap size=%llu bytes]\n", - ref->dev_addr, entry->size, ref->size); - } - - if (ref->type != entry->type) { - err_printk(ref->dev, entry, "DMA-API: device driver frees " - "DMA memory with wrong function " - "[device address=0x%016llx] [size=%llu bytes] " - "[mapped as %s] [unmapped as %s]\n", - ref->dev_addr, ref->size, - type2name[entry->type], type2name[ref->type]); - } else if ((entry->type == dma_debug_coherent) && - (phys_addr(ref) != phys_addr(entry))) { - err_printk(ref->dev, entry, "DMA-API: device driver frees " - "DMA memory with different CPU address " - "[device address=0x%016llx] [size=%llu bytes] " - "[cpu alloc address=0x%016llx] " - "[cpu free address=0x%016llx]", - ref->dev_addr, ref->size, - phys_addr(entry), - phys_addr(ref)); - } - - if (ref->sg_call_ents && ref->type == dma_debug_sg && - ref->sg_call_ents != entry->sg_call_ents) { - err_printk(ref->dev, entry, "DMA-API: device driver frees " - "DMA sg list with different entry count " - "[map count=%d] [unmap count=%d]\n", - entry->sg_call_ents, ref->sg_call_ents); - } - - /* - * This may be no bug in reality - but most implementations of the - * DMA API don't handle this properly, so check for it here - */ - if (ref->direction != entry->direction) { - err_printk(ref->dev, entry, "DMA-API: device driver frees " - "DMA memory with different direction " - "[device address=0x%016llx] [size=%llu bytes] " - "[mapped with %s] [unmapped with %s]\n", - ref->dev_addr, ref->size, - dir2name[entry->direction], - dir2name[ref->direction]); - } - - /* - * Drivers should use dma_mapping_error() to check the returned - * addresses of dma_map_single() and dma_map_page(). - * If not, print this warning message. See Documentation/DMA-API.txt. - */ - if (entry->map_err_type == MAP_ERR_NOT_CHECKED) { - err_printk(ref->dev, entry, - "DMA-API: device driver failed to check map error" - "[device address=0x%016llx] [size=%llu bytes] " - "[mapped as %s]", - ref->dev_addr, ref->size, - type2name[entry->type]); - } - - hash_bucket_del(entry); - dma_entry_free(entry); - - put_hash_bucket(bucket, &flags); -} - -static void check_for_stack(struct device *dev, - struct page *page, size_t offset) -{ - void *addr; - struct vm_struct *stack_vm_area = task_stack_vm_area(current); - - if (!stack_vm_area) { - /* Stack is direct-mapped. */ - if (PageHighMem(page)) - return; - addr = page_address(page) + offset; - if (object_is_on_stack(addr)) - err_printk(dev, NULL, "DMA-API: device driver maps memory from stack [addr=%p]\n", addr); - } else { - /* Stack is vmalloced. */ - int i; - - for (i = 0; i < stack_vm_area->nr_pages; i++) { - if (page != stack_vm_area->pages[i]) - continue; - - addr = (u8 *)current->stack + i * PAGE_SIZE + offset; - err_printk(dev, NULL, "DMA-API: device driver maps memory from stack [probable addr=%p]\n", addr); - break; - } - } -} - -static inline bool overlap(void *addr, unsigned long len, void *start, void *end) -{ - unsigned long a1 = (unsigned long)addr; - unsigned long b1 = a1 + len; - unsigned long a2 = (unsigned long)start; - unsigned long b2 = (unsigned long)end; - - return !(b1 <= a2 || a1 >= b2); -} - -static void check_for_illegal_area(struct device *dev, void *addr, unsigned long len) -{ - if (overlap(addr, len, _stext, _etext) || - overlap(addr, len, __start_rodata, __end_rodata)) - err_printk(dev, NULL, "DMA-API: device driver maps memory from kernel text or rodata [addr=%p] [len=%lu]\n", addr, len); -} - -static void check_sync(struct device *dev, - struct dma_debug_entry *ref, - bool to_cpu) -{ - struct dma_debug_entry *entry; - struct hash_bucket *bucket; - unsigned long flags; - - bucket = get_hash_bucket(ref, &flags); - - entry = bucket_find_contain(&bucket, ref, &flags); - - if (!entry) { - err_printk(dev, NULL, "DMA-API: device driver tries " - "to sync DMA memory it has not allocated " - "[device address=0x%016llx] [size=%llu bytes]\n", - (unsigned long long)ref->dev_addr, ref->size); - goto out; - } - - if (ref->size > entry->size) { - err_printk(dev, entry, "DMA-API: device driver syncs" - " DMA memory outside allocated range " - "[device address=0x%016llx] " - "[allocation size=%llu bytes] " - "[sync offset+size=%llu]\n", - entry->dev_addr, entry->size, - ref->size); - } - - if (entry->direction == DMA_BIDIRECTIONAL) - goto out; - - if (ref->direction != entry->direction) { - err_printk(dev, entry, "DMA-API: device driver syncs " - "DMA memory with different direction " - "[device address=0x%016llx] [size=%llu bytes] " - "[mapped with %s] [synced with %s]\n", - (unsigned long long)ref->dev_addr, entry->size, - dir2name[entry->direction], - dir2name[ref->direction]); - } - - if (to_cpu && !(entry->direction == DMA_FROM_DEVICE) && - !(ref->direction == DMA_TO_DEVICE)) - err_printk(dev, entry, "DMA-API: device driver syncs " - "device read-only DMA memory for cpu " - "[device address=0x%016llx] [size=%llu bytes] " - "[mapped with %s] [synced with %s]\n", - (unsigned long long)ref->dev_addr, entry->size, - dir2name[entry->direction], - dir2name[ref->direction]); - - if (!to_cpu && !(entry->direction == DMA_TO_DEVICE) && - !(ref->direction == DMA_FROM_DEVICE)) - err_printk(dev, entry, "DMA-API: device driver syncs " - "device write-only DMA memory to device " - "[device address=0x%016llx] [size=%llu bytes] " - "[mapped with %s] [synced with %s]\n", - (unsigned long long)ref->dev_addr, entry->size, - dir2name[entry->direction], - dir2name[ref->direction]); - - if (ref->sg_call_ents && ref->type == dma_debug_sg && - ref->sg_call_ents != entry->sg_call_ents) { - err_printk(ref->dev, entry, "DMA-API: device driver syncs " - "DMA sg list with different entry count " - "[map count=%d] [sync count=%d]\n", - entry->sg_call_ents, ref->sg_call_ents); - } - -out: - put_hash_bucket(bucket, &flags); -} - -static void check_sg_segment(struct device *dev, struct scatterlist *sg) -{ -#ifdef CONFIG_DMA_API_DEBUG_SG - unsigned int max_seg = dma_get_max_seg_size(dev); - u64 start, end, boundary = dma_get_seg_boundary(dev); - - /* - * Either the driver forgot to set dma_parms appropriately, or - * whoever generated the list forgot to check them. - */ - if (sg->length > max_seg) - err_printk(dev, NULL, "DMA-API: mapping sg segment longer than device claims to support [len=%u] [max=%u]\n", - sg->length, max_seg); - /* - * In some cases this could potentially be the DMA API - * implementation's fault, but it would usually imply that - * the scatterlist was built inappropriately to begin with. - */ - start = sg_dma_address(sg); - end = start + sg_dma_len(sg) - 1; - if ((start ^ end) & ~boundary) - err_printk(dev, NULL, "DMA-API: mapping sg segment across boundary [start=0x%016llx] [end=0x%016llx] [boundary=0x%016llx]\n", - start, end, boundary); -#endif -} - -void debug_dma_map_page(struct device *dev, struct page *page, size_t offset, - size_t size, int direction, dma_addr_t dma_addr, - bool map_single) -{ - struct dma_debug_entry *entry; - - if (unlikely(dma_debug_disabled())) - return; - - if (dma_mapping_error(dev, dma_addr)) - return; - - entry = dma_entry_alloc(); - if (!entry) - return; - - entry->dev = dev; - entry->type = dma_debug_page; - entry->pfn = page_to_pfn(page); - entry->offset = offset, - entry->dev_addr = dma_addr; - entry->size = size; - entry->direction = direction; - entry->map_err_type = MAP_ERR_NOT_CHECKED; - - if (map_single) - entry->type = dma_debug_single; - - check_for_stack(dev, page, offset); - - if (!PageHighMem(page)) { - void *addr = page_address(page) + offset; - - check_for_illegal_area(dev, addr, size); - } - - add_dma_entry(entry); -} -EXPORT_SYMBOL(debug_dma_map_page); - -void debug_dma_mapping_error(struct device *dev, dma_addr_t dma_addr) -{ - struct dma_debug_entry ref; - struct dma_debug_entry *entry; - struct hash_bucket *bucket; - unsigned long flags; - - if (unlikely(dma_debug_disabled())) - return; - - ref.dev = dev; - ref.dev_addr = dma_addr; - bucket = get_hash_bucket(&ref, &flags); - - list_for_each_entry(entry, &bucket->list, list) { - if (!exact_match(&ref, entry)) - continue; - - /* - * The same physical address can be mapped multiple - * times. Without a hardware IOMMU this results in the - * same device addresses being put into the dma-debug - * hash multiple times too. This can result in false - * positives being reported. Therefore we implement a - * best-fit algorithm here which updates the first entry - * from the hash which fits the reference value and is - * not currently listed as being checked. - */ - if (entry->map_err_type == MAP_ERR_NOT_CHECKED) { - entry->map_err_type = MAP_ERR_CHECKED; - break; - } - } - - put_hash_bucket(bucket, &flags); -} -EXPORT_SYMBOL(debug_dma_mapping_error); - -void debug_dma_unmap_page(struct device *dev, dma_addr_t addr, - size_t size, int direction, bool map_single) -{ - struct dma_debug_entry ref = { - .type = dma_debug_page, - .dev = dev, - .dev_addr = addr, - .size = size, - .direction = direction, - }; - - if (unlikely(dma_debug_disabled())) - return; - - if (map_single) - ref.type = dma_debug_single; - - check_unmap(&ref); -} -EXPORT_SYMBOL(debug_dma_unmap_page); - -void debug_dma_map_sg(struct device *dev, struct scatterlist *sg, - int nents, int mapped_ents, int direction) -{ - struct dma_debug_entry *entry; - struct scatterlist *s; - int i; - - if (unlikely(dma_debug_disabled())) - return; - - for_each_sg(sg, s, mapped_ents, i) { - entry = dma_entry_alloc(); - if (!entry) - return; - - entry->type = dma_debug_sg; - entry->dev = dev; - entry->pfn = page_to_pfn(sg_page(s)); - entry->offset = s->offset, - entry->size = sg_dma_len(s); - entry->dev_addr = sg_dma_address(s); - entry->direction = direction; - entry->sg_call_ents = nents; - entry->sg_mapped_ents = mapped_ents; - - check_for_stack(dev, sg_page(s), s->offset); - - if (!PageHighMem(sg_page(s))) { - check_for_illegal_area(dev, sg_virt(s), sg_dma_len(s)); - } - - check_sg_segment(dev, s); - - add_dma_entry(entry); - } -} -EXPORT_SYMBOL(debug_dma_map_sg); - -static int get_nr_mapped_entries(struct device *dev, - struct dma_debug_entry *ref) -{ - struct dma_debug_entry *entry; - struct hash_bucket *bucket; - unsigned long flags; - int mapped_ents; - - bucket = get_hash_bucket(ref, &flags); - entry = bucket_find_exact(bucket, ref); - mapped_ents = 0; - - if (entry) - mapped_ents = entry->sg_mapped_ents; - put_hash_bucket(bucket, &flags); - - return mapped_ents; -} - -void debug_dma_unmap_sg(struct device *dev, struct scatterlist *sglist, - int nelems, int dir) -{ - struct scatterlist *s; - int mapped_ents = 0, i; - - if (unlikely(dma_debug_disabled())) - return; - - for_each_sg(sglist, s, nelems, i) { - - struct dma_debug_entry ref = { - .type = dma_debug_sg, - .dev = dev, - .pfn = page_to_pfn(sg_page(s)), - .offset = s->offset, - .dev_addr = sg_dma_address(s), - .size = sg_dma_len(s), - .direction = dir, - .sg_call_ents = nelems, - }; - - if (mapped_ents && i >= mapped_ents) - break; - - if (!i) - mapped_ents = get_nr_mapped_entries(dev, &ref); - - check_unmap(&ref); - } -} -EXPORT_SYMBOL(debug_dma_unmap_sg); - -void debug_dma_alloc_coherent(struct device *dev, size_t size, - dma_addr_t dma_addr, void *virt) -{ - struct dma_debug_entry *entry; - - if (unlikely(dma_debug_disabled())) - return; - - if (unlikely(virt == NULL)) - return; - - /* handle vmalloc and linear addresses */ - if (!is_vmalloc_addr(virt) && !virt_addr_valid(virt)) - return; - - entry = dma_entry_alloc(); - if (!entry) - return; - - entry->type = dma_debug_coherent; - entry->dev = dev; - entry->offset = offset_in_page(virt); - entry->size = size; - entry->dev_addr = dma_addr; - entry->direction = DMA_BIDIRECTIONAL; - - if (is_vmalloc_addr(virt)) - entry->pfn = vmalloc_to_pfn(virt); - else - entry->pfn = page_to_pfn(virt_to_page(virt)); - - add_dma_entry(entry); -} -EXPORT_SYMBOL(debug_dma_alloc_coherent); - -void debug_dma_free_coherent(struct device *dev, size_t size, - void *virt, dma_addr_t addr) -{ - struct dma_debug_entry ref = { - .type = dma_debug_coherent, - .dev = dev, - .offset = offset_in_page(virt), - .dev_addr = addr, - .size = size, - .direction = DMA_BIDIRECTIONAL, - }; - - /* handle vmalloc and linear addresses */ - if (!is_vmalloc_addr(virt) && !virt_addr_valid(virt)) - return; - - if (is_vmalloc_addr(virt)) - ref.pfn = vmalloc_to_pfn(virt); - else - ref.pfn = page_to_pfn(virt_to_page(virt)); - - if (unlikely(dma_debug_disabled())) - return; - - check_unmap(&ref); -} -EXPORT_SYMBOL(debug_dma_free_coherent); - -void debug_dma_map_resource(struct device *dev, phys_addr_t addr, size_t size, - int direction, dma_addr_t dma_addr) -{ - struct dma_debug_entry *entry; - - if (unlikely(dma_debug_disabled())) - return; - - entry = dma_entry_alloc(); - if (!entry) - return; - - entry->type = dma_debug_resource; - entry->dev = dev; - entry->pfn = PHYS_PFN(addr); - entry->offset = offset_in_page(addr); - entry->size = size; - entry->dev_addr = dma_addr; - entry->direction = direction; - entry->map_err_type = MAP_ERR_NOT_CHECKED; - - add_dma_entry(entry); -} -EXPORT_SYMBOL(debug_dma_map_resource); - -void debug_dma_unmap_resource(struct device *dev, dma_addr_t dma_addr, - size_t size, int direction) -{ - struct dma_debug_entry ref = { - .type = dma_debug_resource, - .dev = dev, - .dev_addr = dma_addr, - .size = size, - .direction = direction, - }; - - if (unlikely(dma_debug_disabled())) - return; - - check_unmap(&ref); -} -EXPORT_SYMBOL(debug_dma_unmap_resource); - -void debug_dma_sync_single_for_cpu(struct device *dev, dma_addr_t dma_handle, - size_t size, int direction) -{ - struct dma_debug_entry ref; - - if (unlikely(dma_debug_disabled())) - return; - - ref.type = dma_debug_single; - ref.dev = dev; - ref.dev_addr = dma_handle; - ref.size = size; - ref.direction = direction; - ref.sg_call_ents = 0; - - check_sync(dev, &ref, true); -} -EXPORT_SYMBOL(debug_dma_sync_single_for_cpu); - -void debug_dma_sync_single_for_device(struct device *dev, - dma_addr_t dma_handle, size_t size, - int direction) -{ - struct dma_debug_entry ref; - - if (unlikely(dma_debug_disabled())) - return; - - ref.type = dma_debug_single; - ref.dev = dev; - ref.dev_addr = dma_handle; - ref.size = size; - ref.direction = direction; - ref.sg_call_ents = 0; - - check_sync(dev, &ref, false); -} -EXPORT_SYMBOL(debug_dma_sync_single_for_device); - -void debug_dma_sync_single_range_for_cpu(struct device *dev, - dma_addr_t dma_handle, - unsigned long offset, size_t size, - int direction) -{ - struct dma_debug_entry ref; - - if (unlikely(dma_debug_disabled())) - return; - - ref.type = dma_debug_single; - ref.dev = dev; - ref.dev_addr = dma_handle; - ref.size = offset + size; - ref.direction = direction; - ref.sg_call_ents = 0; - - check_sync(dev, &ref, true); -} -EXPORT_SYMBOL(debug_dma_sync_single_range_for_cpu); - -void debug_dma_sync_single_range_for_device(struct device *dev, - dma_addr_t dma_handle, - unsigned long offset, - size_t size, int direction) -{ - struct dma_debug_entry ref; - - if (unlikely(dma_debug_disabled())) - return; - - ref.type = dma_debug_single; - ref.dev = dev; - ref.dev_addr = dma_handle; - ref.size = offset + size; - ref.direction = direction; - ref.sg_call_ents = 0; - - check_sync(dev, &ref, false); -} -EXPORT_SYMBOL(debug_dma_sync_single_range_for_device); - -void debug_dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg, - int nelems, int direction) -{ - struct scatterlist *s; - int mapped_ents = 0, i; - - if (unlikely(dma_debug_disabled())) - return; - - for_each_sg(sg, s, nelems, i) { - - struct dma_debug_entry ref = { - .type = dma_debug_sg, - .dev = dev, - .pfn = page_to_pfn(sg_page(s)), - .offset = s->offset, - .dev_addr = sg_dma_address(s), - .size = sg_dma_len(s), - .direction = direction, - .sg_call_ents = nelems, - }; - - if (!i) - mapped_ents = get_nr_mapped_entries(dev, &ref); - - if (i >= mapped_ents) - break; - - check_sync(dev, &ref, true); - } -} -EXPORT_SYMBOL(debug_dma_sync_sg_for_cpu); - -void debug_dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg, - int nelems, int direction) -{ - struct scatterlist *s; - int mapped_ents = 0, i; - - if (unlikely(dma_debug_disabled())) - return; - - for_each_sg(sg, s, nelems, i) { - - struct dma_debug_entry ref = { - .type = dma_debug_sg, - .dev = dev, - .pfn = page_to_pfn(sg_page(s)), - .offset = s->offset, - .dev_addr = sg_dma_address(s), - .size = sg_dma_len(s), - .direction = direction, - .sg_call_ents = nelems, - }; - if (!i) - mapped_ents = get_nr_mapped_entries(dev, &ref); - - if (i >= mapped_ents) - break; - - check_sync(dev, &ref, false); - } -} -EXPORT_SYMBOL(debug_dma_sync_sg_for_device); - -static int __init dma_debug_driver_setup(char *str) -{ - int i; - - for (i = 0; i < NAME_MAX_LEN - 1; ++i, ++str) { - current_driver_name[i] = *str; - if (*str == 0) - break; - } - - if (current_driver_name[0]) - pr_info("DMA-API: enable driver filter for driver [%s]\n", - current_driver_name); - - - return 1; -} -__setup("dma_debug_driver=", dma_debug_driver_setup); diff --git a/lib/dma-direct.c b/lib/dma-direct.c deleted file mode 100644 index 8be8106270c2..000000000000 --- a/lib/dma-direct.c +++ /dev/null @@ -1,204 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 -/* - * DMA operations that map physical memory directly without using an IOMMU or - * flushing caches. - */ -#include -#include -#include -#include -#include -#include -#include - -#define DIRECT_MAPPING_ERROR 0 - -/* - * Most architectures use ZONE_DMA for the first 16 Megabytes, but - * some use it for entirely different regions: - */ -#ifndef ARCH_ZONE_DMA_BITS -#define ARCH_ZONE_DMA_BITS 24 -#endif - -/* - * For AMD SEV all DMA must be to unencrypted addresses. - */ -static inline bool force_dma_unencrypted(void) -{ - return sev_active(); -} - -static bool -check_addr(struct device *dev, dma_addr_t dma_addr, size_t size, - const char *caller) -{ - if (unlikely(dev && !dma_capable(dev, dma_addr, size))) { - if (!dev->dma_mask) { - dev_err(dev, - "%s: call on device without dma_mask\n", - caller); - return false; - } - - if (*dev->dma_mask >= DMA_BIT_MASK(32)) { - dev_err(dev, - "%s: overflow %pad+%zu of device mask %llx\n", - caller, &dma_addr, size, *dev->dma_mask); - } - return false; - } - return true; -} - -static bool dma_coherent_ok(struct device *dev, phys_addr_t phys, size_t size) -{ - dma_addr_t addr = force_dma_unencrypted() ? - __phys_to_dma(dev, phys) : phys_to_dma(dev, phys); - return addr + size - 1 <= dev->coherent_dma_mask; -} - -void *dma_direct_alloc(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; - void *ret; - - /* we always manually zero the memory once we are done: */ - gfp &= ~__GFP_ZERO; - - /* GFP_DMA32 and GFP_DMA are no ops without the corresponding zones: */ - if (dev->coherent_dma_mask <= DMA_BIT_MASK(ARCH_ZONE_DMA_BITS)) - gfp |= GFP_DMA; - if (dev->coherent_dma_mask <= DMA_BIT_MASK(32) && !(gfp & GFP_DMA)) - gfp |= GFP_DMA32; - -again: - /* CMA can be used only in the context which permits sleeping */ - if (gfpflags_allow_blocking(gfp)) { - page = dma_alloc_from_contiguous(dev, count, page_order, gfp); - if (page && !dma_coherent_ok(dev, page_to_phys(page), size)) { - dma_release_from_contiguous(dev, page, count); - page = NULL; - } - } - if (!page) - page = alloc_pages_node(dev_to_node(dev), gfp, page_order); - - if (page && !dma_coherent_ok(dev, page_to_phys(page), size)) { - __free_pages(page, page_order); - page = NULL; - - if (IS_ENABLED(CONFIG_ZONE_DMA32) && - dev->coherent_dma_mask < DMA_BIT_MASK(64) && - !(gfp & (GFP_DMA32 | GFP_DMA))) { - gfp |= GFP_DMA32; - goto again; - } - - if (IS_ENABLED(CONFIG_ZONE_DMA) && - dev->coherent_dma_mask < DMA_BIT_MASK(32) && - !(gfp & GFP_DMA)) { - gfp = (gfp & ~GFP_DMA32) | GFP_DMA; - goto again; - } - } - - if (!page) - return NULL; - ret = page_address(page); - if (force_dma_unencrypted()) { - set_memory_decrypted((unsigned long)ret, 1 << page_order); - *dma_handle = __phys_to_dma(dev, page_to_phys(page)); - } else { - *dma_handle = phys_to_dma(dev, page_to_phys(page)); - } - memset(ret, 0, 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(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_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) -{ - dma_addr_t dma_addr = phys_to_dma(dev, page_to_phys(page)) + offset; - - if (!check_addr(dev, dma_addr, size, __func__)) - return DIRECT_MAPPING_ERROR; - return dma_addr; -} - -int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl, int nents, - enum dma_data_direction dir, unsigned long attrs) -{ - int i; - struct scatterlist *sg; - - for_each_sg(sgl, sg, nents, i) { - BUG_ON(!sg_page(sg)); - - sg_dma_address(sg) = phys_to_dma(dev, sg_phys(sg)); - if (!check_addr(dev, sg_dma_address(sg), sg->length, __func__)) - return 0; - sg_dma_len(sg) = sg->length; - } - - return nents; -} - -int dma_direct_supported(struct device *dev, u64 mask) -{ -#ifdef CONFIG_ZONE_DMA - if (mask < DMA_BIT_MASK(ARCH_ZONE_DMA_BITS)) - return 0; -#else - /* - * Because 32-bit DMA masks are so common we expect every architecture - * to be able to satisfy them - either by not supporting more physical - * memory, or by providing a ZONE_DMA32. If neither is the case, the - * architecture needs to use an IOMMU instead of the direct mapping. - */ - if (mask < DMA_BIT_MASK(32)) - return 0; -#endif - /* - * Various PCI/PCIe bridges have broken support for > 32bit DMA even - * if the device itself might support it. - */ - if (dev->dma_32bit_limit && mask > DMA_BIT_MASK(32)) - return 0; - return 1; -} - -int dma_direct_mapping_error(struct device *dev, dma_addr_t dma_addr) -{ - return dma_addr == DIRECT_MAPPING_ERROR; -} - -const struct dma_map_ops dma_direct_ops = { - .alloc = dma_direct_alloc, - .free = dma_direct_free, - .map_page = dma_direct_map_page, - .map_sg = dma_direct_map_sg, - .dma_supported = dma_direct_supported, - .mapping_error = dma_direct_mapping_error, -}; -EXPORT_SYMBOL(dma_direct_ops); diff --git a/lib/dma-noncoherent.c b/lib/dma-noncoherent.c deleted file mode 100644 index 79e9a757387f..000000000000 --- a/lib/dma-noncoherent.c +++ /dev/null @@ -1,102 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 -/* - * Copyright (C) 2018 Christoph Hellwig. - * - * DMA operations that map physical memory directly without providing cache - * coherence. - */ -#include -#include -#include -#include -#include - -static void dma_noncoherent_sync_single_for_device(struct device *dev, - dma_addr_t addr, size_t size, enum dma_data_direction dir) -{ - arch_sync_dma_for_device(dev, dma_to_phys(dev, addr), size, dir); -} - -static void dma_noncoherent_sync_sg_for_device(struct device *dev, - struct scatterlist *sgl, int nents, enum dma_data_direction dir) -{ - struct scatterlist *sg; - int i; - - for_each_sg(sgl, sg, nents, i) - arch_sync_dma_for_device(dev, sg_phys(sg), sg->length, dir); -} - -static dma_addr_t dma_noncoherent_map_page(struct device *dev, struct page *page, - unsigned long offset, size_t size, enum dma_data_direction dir, - unsigned long attrs) -{ - dma_addr_t addr; - - addr = dma_direct_map_page(dev, page, offset, size, dir, attrs); - if (!dma_mapping_error(dev, addr) && !(attrs & DMA_ATTR_SKIP_CPU_SYNC)) - arch_sync_dma_for_device(dev, page_to_phys(page) + offset, - size, dir); - return addr; -} - -static int dma_noncoherent_map_sg(struct device *dev, struct scatterlist *sgl, - int nents, enum dma_data_direction dir, unsigned long attrs) -{ - nents = dma_direct_map_sg(dev, sgl, nents, dir, attrs); - if (nents > 0 && !(attrs & DMA_ATTR_SKIP_CPU_SYNC)) - dma_noncoherent_sync_sg_for_device(dev, sgl, nents, dir); - return nents; -} - -#ifdef CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU -static void dma_noncoherent_sync_single_for_cpu(struct device *dev, - dma_addr_t addr, size_t size, enum dma_data_direction dir) -{ - arch_sync_dma_for_cpu(dev, dma_to_phys(dev, addr), size, dir); -} - -static void dma_noncoherent_sync_sg_for_cpu(struct device *dev, - struct scatterlist *sgl, int nents, enum dma_data_direction dir) -{ - struct scatterlist *sg; - int i; - - for_each_sg(sgl, sg, nents, i) - arch_sync_dma_for_cpu(dev, sg_phys(sg), sg->length, dir); -} - -static void dma_noncoherent_unmap_page(struct device *dev, dma_addr_t addr, - size_t size, enum dma_data_direction dir, unsigned long attrs) -{ - if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC)) - dma_noncoherent_sync_single_for_cpu(dev, addr, size, dir); -} - -static void dma_noncoherent_unmap_sg(struct device *dev, struct scatterlist *sgl, - int nents, enum dma_data_direction dir, unsigned long attrs) -{ - if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC)) - dma_noncoherent_sync_sg_for_cpu(dev, sgl, nents, dir); -} -#endif - -const struct dma_map_ops dma_noncoherent_ops = { - .alloc = arch_dma_alloc, - .free = arch_dma_free, - .mmap = arch_dma_mmap, - .sync_single_for_device = dma_noncoherent_sync_single_for_device, - .sync_sg_for_device = dma_noncoherent_sync_sg_for_device, - .map_page = dma_noncoherent_map_page, - .map_sg = dma_noncoherent_map_sg, -#ifdef CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU - .sync_single_for_cpu = dma_noncoherent_sync_single_for_cpu, - .sync_sg_for_cpu = dma_noncoherent_sync_sg_for_cpu, - .unmap_page = dma_noncoherent_unmap_page, - .unmap_sg = dma_noncoherent_unmap_sg, -#endif - .dma_supported = dma_direct_supported, - .mapping_error = dma_direct_mapping_error, - .cache_sync = arch_dma_cache_sync, -}; -EXPORT_SYMBOL(dma_noncoherent_ops); diff --git a/lib/dma-virt.c b/lib/dma-virt.c deleted file mode 100644 index 8e61a02ef9ca..000000000000 --- a/lib/dma-virt.c +++ /dev/null @@ -1,61 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 -/* - * lib/dma-virt.c - * - * DMA operations that map to virtual addresses without flushing memory. - */ -#include -#include -#include -#include - -static void *dma_virt_alloc(struct device *dev, size_t size, - dma_addr_t *dma_handle, gfp_t gfp, - unsigned long attrs) -{ - void *ret; - - ret = (void *)__get_free_pages(gfp, get_order(size)); - if (ret) - *dma_handle = (uintptr_t)ret; - return ret; -} - -static void dma_virt_free(struct device *dev, size_t size, - void *cpu_addr, dma_addr_t dma_addr, - unsigned long attrs) -{ - free_pages((unsigned long)cpu_addr, get_order(size)); -} - -static dma_addr_t dma_virt_map_page(struct device *dev, struct page *page, - unsigned long offset, size_t size, - enum dma_data_direction dir, - unsigned long attrs) -{ - return (uintptr_t)(page_address(page) + offset); -} - -static int dma_virt_map_sg(struct device *dev, struct scatterlist *sgl, - int nents, enum dma_data_direction dir, - unsigned long attrs) -{ - int i; - struct scatterlist *sg; - - for_each_sg(sgl, sg, nents, i) { - BUG_ON(!sg_page(sg)); - sg_dma_address(sg) = (uintptr_t)sg_virt(sg); - sg_dma_len(sg) = sg->length; - } - - return nents; -} - -const struct dma_map_ops dma_virt_ops = { - .alloc = dma_virt_alloc, - .free = dma_virt_free, - .map_page = dma_virt_map_page, - .map_sg = dma_virt_map_sg, -}; -EXPORT_SYMBOL(dma_virt_ops); diff --git a/lib/swiotlb.c b/lib/swiotlb.c deleted file mode 100644 index 04b68d9dffac..000000000000 --- a/lib/swiotlb.c +++ /dev/null @@ -1,1087 +0,0 @@ -/* - * Dynamic DMA mapping support. - * - * This implementation is a fallback for platforms that do not support - * I/O TLBs (aka DMA address translation hardware). - * Copyright (C) 2000 Asit Mallick - * Copyright (C) 2000 Goutham Rao - * Copyright (C) 2000, 2003 Hewlett-Packard Co - * David Mosberger-Tang - * - * 03/05/07 davidm Switch from PCI-DMA to generic device DMA API. - * 00/12/13 davidm Rename to swiotlb.c and add mark_clean() to avoid - * unnecessary i-cache flushing. - * 04/07/.. ak Better overflow handling. Assorted fixes. - * 05/09/10 linville Add support for syncing ranges, support syncing for - * DMA_BIDIRECTIONAL mappings, miscellaneous cleanup. - * 08/12/11 beckyb Add highmem support - */ - -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include - -#include -#include - -#include -#include -#include - -#define CREATE_TRACE_POINTS -#include - -#define OFFSET(val,align) ((unsigned long) \ - ( (val) & ( (align) - 1))) - -#define SLABS_PER_PAGE (1 << (PAGE_SHIFT - IO_TLB_SHIFT)) - -/* - * Minimum IO TLB size to bother booting with. Systems with mainly - * 64bit capable cards will only lightly use the swiotlb. If we can't - * allocate a contiguous 1MB, we're probably in trouble anyway. - */ -#define IO_TLB_MIN_SLABS ((1<<20) >> IO_TLB_SHIFT) - -enum swiotlb_force swiotlb_force; - -/* - * Used to do a quick range check in swiotlb_tbl_unmap_single and - * swiotlb_tbl_sync_single_*, to see if the memory was in fact allocated by this - * API. - */ -static phys_addr_t io_tlb_start, io_tlb_end; - -/* - * The number of IO TLB blocks (in groups of 64) between io_tlb_start and - * io_tlb_end. This is command line adjustable via setup_io_tlb_npages. - */ -static unsigned long io_tlb_nslabs; - -/* - * When the IOMMU overflows we return a fallback buffer. This sets the size. - */ -static unsigned long io_tlb_overflow = 32*1024; - -static phys_addr_t io_tlb_overflow_buffer; - -/* - * This is a free list describing the number of free entries available from - * each index - */ -static unsigned int *io_tlb_list; -static unsigned int io_tlb_index; - -/* - * Max segment that we can provide which (if pages are contingous) will - * not be bounced (unless SWIOTLB_FORCE is set). - */ -unsigned int max_segment; - -/* - * We need to save away the original address corresponding to a mapped entry - * for the sync operations. - */ -#define INVALID_PHYS_ADDR (~(phys_addr_t)0) -static phys_addr_t *io_tlb_orig_addr; - -/* - * Protect the above data structures in the map and unmap calls - */ -static DEFINE_SPINLOCK(io_tlb_lock); - -static int late_alloc; - -static int __init -setup_io_tlb_npages(char *str) -{ - if (isdigit(*str)) { - io_tlb_nslabs = simple_strtoul(str, &str, 0); - /* avoid tail segment of size < IO_TLB_SEGSIZE */ - io_tlb_nslabs = ALIGN(io_tlb_nslabs, IO_TLB_SEGSIZE); - } - if (*str == ',') - ++str; - if (!strcmp(str, "force")) { - swiotlb_force = SWIOTLB_FORCE; - } else if (!strcmp(str, "noforce")) { - swiotlb_force = SWIOTLB_NO_FORCE; - io_tlb_nslabs = 1; - } - - return 0; -} -early_param("swiotlb", setup_io_tlb_npages); -/* make io_tlb_overflow tunable too? */ - -unsigned long swiotlb_nr_tbl(void) -{ - return io_tlb_nslabs; -} -EXPORT_SYMBOL_GPL(swiotlb_nr_tbl); - -unsigned int swiotlb_max_segment(void) -{ - return max_segment; -} -EXPORT_SYMBOL_GPL(swiotlb_max_segment); - -void swiotlb_set_max_segment(unsigned int val) -{ - if (swiotlb_force == SWIOTLB_FORCE) - max_segment = 1; - else - max_segment = rounddown(val, PAGE_SIZE); -} - -/* default to 64MB */ -#define IO_TLB_DEFAULT_SIZE (64UL<<20) -unsigned long swiotlb_size_or_default(void) -{ - unsigned long size; - - size = io_tlb_nslabs << IO_TLB_SHIFT; - - return size ? size : (IO_TLB_DEFAULT_SIZE); -} - -static bool no_iotlb_memory; - -void swiotlb_print_info(void) -{ - unsigned long bytes = io_tlb_nslabs << IO_TLB_SHIFT; - unsigned char *vstart, *vend; - - if (no_iotlb_memory) { - pr_warn("software IO TLB: No low mem\n"); - return; - } - - vstart = phys_to_virt(io_tlb_start); - vend = phys_to_virt(io_tlb_end); - - printk(KERN_INFO "software IO TLB [mem %#010llx-%#010llx] (%luMB) mapped at [%p-%p]\n", - (unsigned long long)io_tlb_start, - (unsigned long long)io_tlb_end, - bytes >> 20, vstart, vend - 1); -} - -/* - * Early SWIOTLB allocation may be too early to allow an architecture to - * perform the desired operations. This function allows the architecture to - * call SWIOTLB when the operations are possible. It needs to be called - * before the SWIOTLB memory is used. - */ -void __init swiotlb_update_mem_attributes(void) -{ - void *vaddr; - unsigned long bytes; - - if (no_iotlb_memory || late_alloc) - return; - - vaddr = phys_to_virt(io_tlb_start); - bytes = PAGE_ALIGN(io_tlb_nslabs << IO_TLB_SHIFT); - set_memory_decrypted((unsigned long)vaddr, bytes >> PAGE_SHIFT); - memset(vaddr, 0, bytes); - - vaddr = phys_to_virt(io_tlb_overflow_buffer); - bytes = PAGE_ALIGN(io_tlb_overflow); - set_memory_decrypted((unsigned long)vaddr, bytes >> PAGE_SHIFT); - memset(vaddr, 0, bytes); -} - -int __init swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose) -{ - void *v_overflow_buffer; - unsigned long i, bytes; - - bytes = nslabs << IO_TLB_SHIFT; - - io_tlb_nslabs = nslabs; - io_tlb_start = __pa(tlb); - io_tlb_end = io_tlb_start + bytes; - - /* - * Get the overflow emergency buffer - */ - v_overflow_buffer = memblock_virt_alloc_low_nopanic( - PAGE_ALIGN(io_tlb_overflow), - PAGE_SIZE); - if (!v_overflow_buffer) - return -ENOMEM; - - io_tlb_overflow_buffer = __pa(v_overflow_buffer); - - /* - * Allocate and initialize the free list array. This array is used - * to find contiguous free memory regions of size up to IO_TLB_SEGSIZE - * between io_tlb_start and io_tlb_end. - */ - io_tlb_list = memblock_virt_alloc( - PAGE_ALIGN(io_tlb_nslabs * sizeof(int)), - PAGE_SIZE); - io_tlb_orig_addr = memblock_virt_alloc( - PAGE_ALIGN(io_tlb_nslabs * sizeof(phys_addr_t)), - PAGE_SIZE); - for (i = 0; i < io_tlb_nslabs; i++) { - io_tlb_list[i] = IO_TLB_SEGSIZE - OFFSET(i, IO_TLB_SEGSIZE); - io_tlb_orig_addr[i] = INVALID_PHYS_ADDR; - } - io_tlb_index = 0; - - if (verbose) - swiotlb_print_info(); - - swiotlb_set_max_segment(io_tlb_nslabs << IO_TLB_SHIFT); - return 0; -} - -/* - * Statically reserve bounce buffer space and initialize bounce buffer data - * structures for the software IO TLB used to implement the DMA API. - */ -void __init -swiotlb_init(int verbose) -{ - size_t default_size = IO_TLB_DEFAULT_SIZE; - unsigned char *vstart; - unsigned long bytes; - - if (!io_tlb_nslabs) { - io_tlb_nslabs = (default_size >> IO_TLB_SHIFT); - io_tlb_nslabs = ALIGN(io_tlb_nslabs, IO_TLB_SEGSIZE); - } - - bytes = io_tlb_nslabs << IO_TLB_SHIFT; - - /* Get IO TLB memory from the low pages */ - vstart = memblock_virt_alloc_low_nopanic(PAGE_ALIGN(bytes), PAGE_SIZE); - if (vstart && !swiotlb_init_with_tbl(vstart, io_tlb_nslabs, verbose)) - return; - - if (io_tlb_start) - memblock_free_early(io_tlb_start, - PAGE_ALIGN(io_tlb_nslabs << IO_TLB_SHIFT)); - pr_warn("Cannot allocate SWIOTLB buffer"); - no_iotlb_memory = true; -} - -/* - * Systems with larger DMA zones (those that don't support ISA) can - * initialize the swiotlb later using the slab allocator if needed. - * This should be just like above, but with some error catching. - */ -int -swiotlb_late_init_with_default_size(size_t default_size) -{ - unsigned long bytes, req_nslabs = io_tlb_nslabs; - unsigned char *vstart = NULL; - unsigned int order; - int rc = 0; - - if (!io_tlb_nslabs) { - io_tlb_nslabs = (default_size >> IO_TLB_SHIFT); - io_tlb_nslabs = ALIGN(io_tlb_nslabs, IO_TLB_SEGSIZE); - } - - /* - * Get IO TLB memory from the low pages - */ - order = get_order(io_tlb_nslabs << IO_TLB_SHIFT); - io_tlb_nslabs = SLABS_PER_PAGE << order; - bytes = io_tlb_nslabs << IO_TLB_SHIFT; - - while ((SLABS_PER_PAGE << order) > IO_TLB_MIN_SLABS) { - vstart = (void *)__get_free_pages(GFP_DMA | __GFP_NOWARN, - order); - if (vstart) - break; - order--; - } - - if (!vstart) { - io_tlb_nslabs = req_nslabs; - return -ENOMEM; - } - if (order != get_order(bytes)) { - printk(KERN_WARNING "Warning: only able to allocate %ld MB " - "for software IO TLB\n", (PAGE_SIZE << order) >> 20); - io_tlb_nslabs = SLABS_PER_PAGE << order; - } - rc = swiotlb_late_init_with_tbl(vstart, io_tlb_nslabs); - if (rc) - free_pages((unsigned long)vstart, order); - - return rc; -} - -int -swiotlb_late_init_with_tbl(char *tlb, unsigned long nslabs) -{ - unsigned long i, bytes; - unsigned char *v_overflow_buffer; - - bytes = nslabs << IO_TLB_SHIFT; - - io_tlb_nslabs = nslabs; - io_tlb_start = virt_to_phys(tlb); - io_tlb_end = io_tlb_start + bytes; - - set_memory_decrypted((unsigned long)tlb, bytes >> PAGE_SHIFT); - memset(tlb, 0, bytes); - - /* - * Get the overflow emergency buffer - */ - v_overflow_buffer = (void *)__get_free_pages(GFP_DMA, - get_order(io_tlb_overflow)); - if (!v_overflow_buffer) - goto cleanup2; - - set_memory_decrypted((unsigned long)v_overflow_buffer, - io_tlb_overflow >> PAGE_SHIFT); - memset(v_overflow_buffer, 0, io_tlb_overflow); - io_tlb_overflow_buffer = virt_to_phys(v_overflow_buffer); - - /* - * Allocate and initialize the free list array. This array is used - * to find contiguous free memory regions of size up to IO_TLB_SEGSIZE - * between io_tlb_start and io_tlb_end. - */ - io_tlb_list = (unsigned int *)__get_free_pages(GFP_KERNEL, - get_order(io_tlb_nslabs * sizeof(int))); - if (!io_tlb_list) - goto cleanup3; - - io_tlb_orig_addr = (phys_addr_t *) - __get_free_pages(GFP_KERNEL, - get_order(io_tlb_nslabs * - sizeof(phys_addr_t))); - if (!io_tlb_orig_addr) - goto cleanup4; - - for (i = 0; i < io_tlb_nslabs; i++) { - io_tlb_list[i] = IO_TLB_SEGSIZE - OFFSET(i, IO_TLB_SEGSIZE); - io_tlb_orig_addr[i] = INVALID_PHYS_ADDR; - } - io_tlb_index = 0; - - swiotlb_print_info(); - - late_alloc = 1; - - swiotlb_set_max_segment(io_tlb_nslabs << IO_TLB_SHIFT); - - return 0; - -cleanup4: - free_pages((unsigned long)io_tlb_list, get_order(io_tlb_nslabs * - sizeof(int))); - io_tlb_list = NULL; -cleanup3: - free_pages((unsigned long)v_overflow_buffer, - get_order(io_tlb_overflow)); - io_tlb_overflow_buffer = 0; -cleanup2: - io_tlb_end = 0; - io_tlb_start = 0; - io_tlb_nslabs = 0; - max_segment = 0; - return -ENOMEM; -} - -void __init swiotlb_exit(void) -{ - if (!io_tlb_orig_addr) - return; - - if (late_alloc) { - free_pages((unsigned long)phys_to_virt(io_tlb_overflow_buffer), - get_order(io_tlb_overflow)); - free_pages((unsigned long)io_tlb_orig_addr, - get_order(io_tlb_nslabs * sizeof(phys_addr_t))); - free_pages((unsigned long)io_tlb_list, get_order(io_tlb_nslabs * - sizeof(int))); - free_pages((unsigned long)phys_to_virt(io_tlb_start), - get_order(io_tlb_nslabs << IO_TLB_SHIFT)); - } else { - memblock_free_late(io_tlb_overflow_buffer, - PAGE_ALIGN(io_tlb_overflow)); - memblock_free_late(__pa(io_tlb_orig_addr), - PAGE_ALIGN(io_tlb_nslabs * sizeof(phys_addr_t))); - memblock_free_late(__pa(io_tlb_list), - PAGE_ALIGN(io_tlb_nslabs * sizeof(int))); - memblock_free_late(io_tlb_start, - PAGE_ALIGN(io_tlb_nslabs << IO_TLB_SHIFT)); - } - io_tlb_nslabs = 0; - max_segment = 0; -} - -int is_swiotlb_buffer(phys_addr_t paddr) -{ - return paddr >= io_tlb_start && paddr < io_tlb_end; -} - -/* - * Bounce: copy the swiotlb buffer back to the original dma location - */ -static void swiotlb_bounce(phys_addr_t orig_addr, phys_addr_t tlb_addr, - size_t size, enum dma_data_direction dir) -{ - unsigned long pfn = PFN_DOWN(orig_addr); - unsigned char *vaddr = phys_to_virt(tlb_addr); - - if (PageHighMem(pfn_to_page(pfn))) { - /* The buffer does not have a mapping. Map it in and copy */ - unsigned int offset = orig_addr & ~PAGE_MASK; - char *buffer; - unsigned int sz = 0; - unsigned long flags; - - while (size) { - sz = min_t(size_t, PAGE_SIZE - offset, size); - - local_irq_save(flags); - buffer = kmap_atomic(pfn_to_page(pfn)); - if (dir == DMA_TO_DEVICE) - memcpy(vaddr, buffer + offset, sz); - else - memcpy(buffer + offset, vaddr, sz); - kunmap_atomic(buffer); - local_irq_restore(flags); - - size -= sz; - pfn++; - vaddr += sz; - offset = 0; - } - } else if (dir == DMA_TO_DEVICE) { - memcpy(vaddr, phys_to_virt(orig_addr), size); - } else { - memcpy(phys_to_virt(orig_addr), vaddr, size); - } -} - -phys_addr_t swiotlb_tbl_map_single(struct device *hwdev, - dma_addr_t tbl_dma_addr, - phys_addr_t orig_addr, size_t size, - enum dma_data_direction dir, - unsigned long attrs) -{ - unsigned long flags; - phys_addr_t tlb_addr; - unsigned int nslots, stride, index, wrap; - int i; - unsigned long mask; - unsigned long offset_slots; - unsigned long max_slots; - - if (no_iotlb_memory) - panic("Can not allocate SWIOTLB buffer earlier and can't now provide you with the DMA bounce buffer"); - - if (mem_encrypt_active()) - pr_warn_once("%s is active and system is using DMA bounce buffers\n", - sme_active() ? "SME" : "SEV"); - - mask = dma_get_seg_boundary(hwdev); - - tbl_dma_addr &= mask; - - offset_slots = ALIGN(tbl_dma_addr, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT; - - /* - * Carefully handle integer overflow which can occur when mask == ~0UL. - */ - max_slots = mask + 1 - ? ALIGN(mask + 1, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT - : 1UL << (BITS_PER_LONG - IO_TLB_SHIFT); - - /* - * For mappings greater than or equal to a page, we limit the stride - * (and hence alignment) to a page size. - */ - nslots = ALIGN(size, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT; - if (size >= PAGE_SIZE) - stride = (1 << (PAGE_SHIFT - IO_TLB_SHIFT)); - else - stride = 1; - - BUG_ON(!nslots); - - /* - * Find suitable number of IO TLB entries size that will fit this - * request and allocate a buffer from that IO TLB pool. - */ - spin_lock_irqsave(&io_tlb_lock, flags); - index = ALIGN(io_tlb_index, stride); - if (index >= io_tlb_nslabs) - index = 0; - wrap = index; - - do { - while (iommu_is_span_boundary(index, nslots, offset_slots, - max_slots)) { - index += stride; - if (index >= io_tlb_nslabs) - index = 0; - if (index == wrap) - goto not_found; - } - - /* - * If we find a slot that indicates we have 'nslots' number of - * contiguous buffers, we allocate the buffers from that slot - * and mark the entries as '0' indicating unavailable. - */ - if (io_tlb_list[index] >= nslots) { - int count = 0; - - for (i = index; i < (int) (index + nslots); i++) - io_tlb_list[i] = 0; - for (i = index - 1; (OFFSET(i, IO_TLB_SEGSIZE) != IO_TLB_SEGSIZE - 1) && io_tlb_list[i]; i--) - io_tlb_list[i] = ++count; - tlb_addr = io_tlb_start + (index << IO_TLB_SHIFT); - - /* - * Update the indices to avoid searching in the next - * round. - */ - io_tlb_index = ((index + nslots) < io_tlb_nslabs - ? (index + nslots) : 0); - - goto found; - } - index += stride; - if (index >= io_tlb_nslabs) - index = 0; - } while (index != wrap); - -not_found: - spin_unlock_irqrestore(&io_tlb_lock, flags); - if (!(attrs & DMA_ATTR_NO_WARN) && printk_ratelimit()) - dev_warn(hwdev, "swiotlb buffer is full (sz: %zd bytes)\n", size); - return SWIOTLB_MAP_ERROR; -found: - spin_unlock_irqrestore(&io_tlb_lock, flags); - - /* - * Save away the mapping from the original address to the DMA address. - * This is needed when we sync the memory. Then we sync the buffer if - * needed. - */ - for (i = 0; i < nslots; i++) - io_tlb_orig_addr[index+i] = orig_addr + (i << IO_TLB_SHIFT); - if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC) && - (dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL)) - swiotlb_bounce(orig_addr, tlb_addr, size, DMA_TO_DEVICE); - - return tlb_addr; -} - -/* - * Allocates bounce buffer and returns its physical address. - */ -static phys_addr_t -map_single(struct device *hwdev, phys_addr_t phys, size_t size, - enum dma_data_direction dir, unsigned long attrs) -{ - dma_addr_t start_dma_addr; - - if (swiotlb_force == SWIOTLB_NO_FORCE) { - dev_warn_ratelimited(hwdev, "Cannot do DMA to address %pa\n", - &phys); - return SWIOTLB_MAP_ERROR; - } - - start_dma_addr = __phys_to_dma(hwdev, io_tlb_start); - return swiotlb_tbl_map_single(hwdev, start_dma_addr, phys, size, - dir, attrs); -} - -/* - * tlb_addr is the physical address of the bounce buffer to unmap. - */ -void swiotlb_tbl_unmap_single(struct device *hwdev, phys_addr_t tlb_addr, - size_t size, enum dma_data_direction dir, - unsigned long attrs) -{ - unsigned long flags; - int i, count, nslots = ALIGN(size, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT; - int index = (tlb_addr - io_tlb_start) >> IO_TLB_SHIFT; - phys_addr_t orig_addr = io_tlb_orig_addr[index]; - - /* - * First, sync the memory before unmapping the entry - */ - if (orig_addr != INVALID_PHYS_ADDR && - !(attrs & DMA_ATTR_SKIP_CPU_SYNC) && - ((dir == DMA_FROM_DEVICE) || (dir == DMA_BIDIRECTIONAL))) - swiotlb_bounce(orig_addr, tlb_addr, size, DMA_FROM_DEVICE); - - /* - * Return the buffer to the free list by setting the corresponding - * entries to indicate the number of contiguous entries available. - * While returning the entries to the free list, we merge the entries - * with slots below and above the pool being returned. - */ - spin_lock_irqsave(&io_tlb_lock, flags); - { - count = ((index + nslots) < ALIGN(index + 1, IO_TLB_SEGSIZE) ? - io_tlb_list[index + nslots] : 0); - /* - * Step 1: return the slots to the free list, merging the - * slots with superceeding slots - */ - for (i = index + nslots - 1; i >= index; i--) { - io_tlb_list[i] = ++count; - io_tlb_orig_addr[i] = INVALID_PHYS_ADDR; - } - /* - * Step 2: merge the returned slots with the preceding slots, - * if available (non zero) - */ - for (i = index - 1; (OFFSET(i, IO_TLB_SEGSIZE) != IO_TLB_SEGSIZE -1) && io_tlb_list[i]; i--) - io_tlb_list[i] = ++count; - } - spin_unlock_irqrestore(&io_tlb_lock, flags); -} - -void swiotlb_tbl_sync_single(struct device *hwdev, phys_addr_t tlb_addr, - size_t size, enum dma_data_direction dir, - enum dma_sync_target target) -{ - int index = (tlb_addr - io_tlb_start) >> IO_TLB_SHIFT; - phys_addr_t orig_addr = io_tlb_orig_addr[index]; - - if (orig_addr == INVALID_PHYS_ADDR) - return; - orig_addr += (unsigned long)tlb_addr & ((1 << IO_TLB_SHIFT) - 1); - - switch (target) { - case SYNC_FOR_CPU: - if (likely(dir == DMA_FROM_DEVICE || dir == DMA_BIDIRECTIONAL)) - swiotlb_bounce(orig_addr, tlb_addr, - size, DMA_FROM_DEVICE); - else - BUG_ON(dir != DMA_TO_DEVICE); - break; - case SYNC_FOR_DEVICE: - if (likely(dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL)) - swiotlb_bounce(orig_addr, tlb_addr, - size, DMA_TO_DEVICE); - else - BUG_ON(dir != DMA_FROM_DEVICE); - break; - default: - BUG(); - } -} - -static inline bool dma_coherent_ok(struct device *dev, dma_addr_t addr, - size_t size) -{ - u64 mask = DMA_BIT_MASK(32); - - if (dev && dev->coherent_dma_mask) - mask = dev->coherent_dma_mask; - return addr + size - 1 <= mask; -} - -static void * -swiotlb_alloc_buffer(struct device *dev, size_t size, dma_addr_t *dma_handle, - unsigned long attrs) -{ - phys_addr_t phys_addr; - - if (swiotlb_force == SWIOTLB_NO_FORCE) - goto out_warn; - - phys_addr = swiotlb_tbl_map_single(dev, - __phys_to_dma(dev, io_tlb_start), - 0, size, DMA_FROM_DEVICE, attrs); - if (phys_addr == SWIOTLB_MAP_ERROR) - goto out_warn; - - *dma_handle = __phys_to_dma(dev, phys_addr); - if (!dma_coherent_ok(dev, *dma_handle, size)) - goto out_unmap; - - memset(phys_to_virt(phys_addr), 0, size); - return phys_to_virt(phys_addr); - -out_unmap: - dev_warn(dev, "hwdev DMA mask = 0x%016Lx, dev_addr = 0x%016Lx\n", - (unsigned long long)dev->coherent_dma_mask, - (unsigned long long)*dma_handle); - - /* - * DMA_TO_DEVICE to avoid memcpy in unmap_single. - * DMA_ATTR_SKIP_CPU_SYNC is optional. - */ - swiotlb_tbl_unmap_single(dev, phys_addr, size, DMA_TO_DEVICE, - DMA_ATTR_SKIP_CPU_SYNC); -out_warn: - if (!(attrs & DMA_ATTR_NO_WARN) && printk_ratelimit()) { - dev_warn(dev, - "swiotlb: coherent allocation failed, size=%zu\n", - size); - dump_stack(); - } - return NULL; -} - -static bool swiotlb_free_buffer(struct device *dev, size_t size, - dma_addr_t dma_addr) -{ - phys_addr_t phys_addr = dma_to_phys(dev, dma_addr); - - WARN_ON_ONCE(irqs_disabled()); - - if (!is_swiotlb_buffer(phys_addr)) - return false; - - /* - * DMA_TO_DEVICE to avoid memcpy in swiotlb_tbl_unmap_single. - * DMA_ATTR_SKIP_CPU_SYNC is optional. - */ - swiotlb_tbl_unmap_single(dev, phys_addr, size, DMA_TO_DEVICE, - DMA_ATTR_SKIP_CPU_SYNC); - return true; -} - -static void -swiotlb_full(struct device *dev, size_t size, enum dma_data_direction dir, - int do_panic) -{ - if (swiotlb_force == SWIOTLB_NO_FORCE) - return; - - /* - * Ran out of IOMMU space for this operation. This is very bad. - * Unfortunately the drivers cannot handle this operation properly. - * unless they check for dma_mapping_error (most don't) - * When the mapping is small enough return a static buffer to limit - * the damage, or panic when the transfer is too big. - */ - dev_err_ratelimited(dev, "DMA: Out of SW-IOMMU space for %zu bytes\n", - size); - - if (size <= io_tlb_overflow || !do_panic) - return; - - if (dir == DMA_BIDIRECTIONAL) - panic("DMA: Random memory could be DMA accessed\n"); - if (dir == DMA_FROM_DEVICE) - panic("DMA: Random memory could be DMA written\n"); - if (dir == DMA_TO_DEVICE) - panic("DMA: Random memory could be DMA read\n"); -} - -/* - * Map a single buffer of the indicated size for DMA in streaming mode. The - * physical address to use is returned. - * - * Once the device is given the dma address, the device owns this memory until - * either swiotlb_unmap_page or swiotlb_dma_sync_single is performed. - */ -dma_addr_t swiotlb_map_page(struct device *dev, struct page *page, - unsigned long offset, size_t size, - enum dma_data_direction dir, - unsigned long attrs) -{ - phys_addr_t map, phys = page_to_phys(page) + offset; - dma_addr_t dev_addr = phys_to_dma(dev, phys); - - BUG_ON(dir == DMA_NONE); - /* - * If the address happens to be in the device's DMA window, - * we can safely return the device addr and not worry about bounce - * buffering it. - */ - if (dma_capable(dev, dev_addr, size) && swiotlb_force != SWIOTLB_FORCE) - return dev_addr; - - trace_swiotlb_bounced(dev, dev_addr, size, swiotlb_force); - - /* Oh well, have to allocate and map a bounce buffer. */ - map = map_single(dev, phys, size, dir, attrs); - if (map == SWIOTLB_MAP_ERROR) { - swiotlb_full(dev, size, dir, 1); - return __phys_to_dma(dev, io_tlb_overflow_buffer); - } - - dev_addr = __phys_to_dma(dev, map); - - /* Ensure that the address returned is DMA'ble */ - if (dma_capable(dev, dev_addr, size)) - return dev_addr; - - attrs |= DMA_ATTR_SKIP_CPU_SYNC; - swiotlb_tbl_unmap_single(dev, map, size, dir, attrs); - - return __phys_to_dma(dev, io_tlb_overflow_buffer); -} - -/* - * Unmap a single streaming mode DMA translation. The dma_addr and size must - * match what was provided for in a previous swiotlb_map_page call. All - * other usages are undefined. - * - * After this call, reads by the cpu to the buffer are guaranteed to see - * whatever the device wrote there. - */ -static void unmap_single(struct device *hwdev, dma_addr_t dev_addr, - size_t size, enum dma_data_direction dir, - unsigned long attrs) -{ - phys_addr_t paddr = dma_to_phys(hwdev, dev_addr); - - BUG_ON(dir == DMA_NONE); - - if (is_swiotlb_buffer(paddr)) { - swiotlb_tbl_unmap_single(hwdev, paddr, size, dir, attrs); - return; - } - - if (dir != DMA_FROM_DEVICE) - return; - - /* - * phys_to_virt doesn't work with hihgmem page but we could - * call dma_mark_clean() with hihgmem page here. However, we - * are fine since dma_mark_clean() is null on POWERPC. We can - * make dma_mark_clean() take a physical address if necessary. - */ - dma_mark_clean(phys_to_virt(paddr), size); -} - -void swiotlb_unmap_page(struct device *hwdev, dma_addr_t dev_addr, - size_t size, enum dma_data_direction dir, - unsigned long attrs) -{ - unmap_single(hwdev, dev_addr, size, dir, attrs); -} - -/* - * Make physical memory consistent for a single streaming mode DMA translation - * after a transfer. - * - * If you perform a swiotlb_map_page() but wish to interrogate the buffer - * using the cpu, yet do not wish to teardown the dma mapping, you must - * call this function before doing so. At the next point you give the dma - * address back to the card, you must first perform a - * swiotlb_dma_sync_for_device, and then the device again owns the buffer - */ -static void -swiotlb_sync_single(struct device *hwdev, dma_addr_t dev_addr, - size_t size, enum dma_data_direction dir, - enum dma_sync_target target) -{ - phys_addr_t paddr = dma_to_phys(hwdev, dev_addr); - - BUG_ON(dir == DMA_NONE); - - if (is_swiotlb_buffer(paddr)) { - swiotlb_tbl_sync_single(hwdev, paddr, size, dir, target); - return; - } - - if (dir != DMA_FROM_DEVICE) - return; - - dma_mark_clean(phys_to_virt(paddr), size); -} - -void -swiotlb_sync_single_for_cpu(struct device *hwdev, dma_addr_t dev_addr, - size_t size, enum dma_data_direction dir) -{ - swiotlb_sync_single(hwdev, dev_addr, size, dir, SYNC_FOR_CPU); -} - -void -swiotlb_sync_single_for_device(struct device *hwdev, dma_addr_t dev_addr, - size_t size, enum dma_data_direction dir) -{ - swiotlb_sync_single(hwdev, dev_addr, size, dir, SYNC_FOR_DEVICE); -} - -/* - * Map a set of buffers described by scatterlist in streaming mode for DMA. - * This is the scatter-gather version of the above swiotlb_map_page - * interface. Here the scatter gather list elements are each tagged with the - * appropriate dma address and length. They are obtained via - * sg_dma_{address,length}(SG). - * - * NOTE: An implementation may be able to use a smaller number of - * DMA address/length pairs than there are SG table elements. - * (for example via virtual mapping capabilities) - * The routine returns the number of addr/length pairs actually - * used, at most nents. - * - * Device ownership issues as mentioned above for swiotlb_map_page are the - * same here. - */ -int -swiotlb_map_sg_attrs(struct device *hwdev, struct scatterlist *sgl, int nelems, - enum dma_data_direction dir, unsigned long attrs) -{ - struct scatterlist *sg; - int i; - - BUG_ON(dir == DMA_NONE); - - for_each_sg(sgl, sg, nelems, i) { - phys_addr_t paddr = sg_phys(sg); - dma_addr_t dev_addr = phys_to_dma(hwdev, paddr); - - if (swiotlb_force == SWIOTLB_FORCE || - !dma_capable(hwdev, dev_addr, sg->length)) { - phys_addr_t map = map_single(hwdev, sg_phys(sg), - sg->length, dir, attrs); - if (map == SWIOTLB_MAP_ERROR) { - /* Don't panic here, we expect map_sg users - to do proper error handling. */ - swiotlb_full(hwdev, sg->length, dir, 0); - attrs |= DMA_ATTR_SKIP_CPU_SYNC; - swiotlb_unmap_sg_attrs(hwdev, sgl, i, dir, - attrs); - sg_dma_len(sgl) = 0; - return 0; - } - sg->dma_address = __phys_to_dma(hwdev, map); - } else - sg->dma_address = dev_addr; - sg_dma_len(sg) = sg->length; - } - return nelems; -} - -/* - * Unmap a set of streaming mode DMA translations. Again, cpu read rules - * concerning calls here are the same as for swiotlb_unmap_page() above. - */ -void -swiotlb_unmap_sg_attrs(struct device *hwdev, struct scatterlist *sgl, - int nelems, enum dma_data_direction dir, - unsigned long attrs) -{ - struct scatterlist *sg; - int i; - - BUG_ON(dir == DMA_NONE); - - for_each_sg(sgl, sg, nelems, i) - unmap_single(hwdev, sg->dma_address, sg_dma_len(sg), dir, - attrs); -} - -/* - * Make physical memory consistent for a set of streaming mode DMA translations - * after a transfer. - * - * The same as swiotlb_sync_single_* but for a scatter-gather list, same rules - * and usage. - */ -static void -swiotlb_sync_sg(struct device *hwdev, struct scatterlist *sgl, - int nelems, enum dma_data_direction dir, - enum dma_sync_target target) -{ - struct scatterlist *sg; - int i; - - for_each_sg(sgl, sg, nelems, i) - swiotlb_sync_single(hwdev, sg->dma_address, - sg_dma_len(sg), dir, target); -} - -void -swiotlb_sync_sg_for_cpu(struct device *hwdev, struct scatterlist *sg, - int nelems, enum dma_data_direction dir) -{ - swiotlb_sync_sg(hwdev, sg, nelems, dir, SYNC_FOR_CPU); -} - -void -swiotlb_sync_sg_for_device(struct device *hwdev, struct scatterlist *sg, - int nelems, enum dma_data_direction dir) -{ - swiotlb_sync_sg(hwdev, sg, nelems, dir, SYNC_FOR_DEVICE); -} - -int -swiotlb_dma_mapping_error(struct device *hwdev, dma_addr_t dma_addr) -{ - return (dma_addr == __phys_to_dma(hwdev, io_tlb_overflow_buffer)); -} - -/* - * Return whether the given device DMA address mask can be supported - * properly. For example, if your device can only drive the low 24-bits - * during bus mastering, then you would pass 0x00ffffff as the mask to - * this function. - */ -int -swiotlb_dma_supported(struct device *hwdev, u64 mask) -{ - return __phys_to_dma(hwdev, io_tlb_end - 1) <= mask; -} - -void *swiotlb_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle, - gfp_t gfp, unsigned long attrs) -{ - void *vaddr; - - /* temporary workaround: */ - if (gfp & __GFP_NOWARN) - attrs |= DMA_ATTR_NO_WARN; - - /* - * Don't print a warning when the first allocation attempt fails. - * swiotlb_alloc_coherent() will print a warning when the DMA memory - * allocation ultimately failed. - */ - gfp |= __GFP_NOWARN; - - vaddr = dma_direct_alloc(dev, size, dma_handle, gfp, attrs); - if (!vaddr) - vaddr = swiotlb_alloc_buffer(dev, size, dma_handle, attrs); - return vaddr; -} - -void swiotlb_free(struct device *dev, size_t size, void *vaddr, - dma_addr_t dma_addr, unsigned long attrs) -{ - if (!swiotlb_free_buffer(dev, size, dma_addr)) - dma_direct_free(dev, size, vaddr, dma_addr, attrs); -} - -const struct dma_map_ops swiotlb_dma_ops = { - .mapping_error = swiotlb_dma_mapping_error, - .alloc = swiotlb_alloc, - .free = swiotlb_free, - .sync_single_for_cpu = swiotlb_sync_single_for_cpu, - .sync_single_for_device = swiotlb_sync_single_for_device, - .sync_sg_for_cpu = swiotlb_sync_sg_for_cpu, - .sync_sg_for_device = swiotlb_sync_sg_for_device, - .map_sg = swiotlb_map_sg_attrs, - .unmap_sg = swiotlb_unmap_sg_attrs, - .map_page = swiotlb_map_page, - .unmap_page = swiotlb_unmap_page, - .dma_supported = dma_direct_supported, -};