diff options
author | Christoph Hellwig <hch@lst.de> | 2018-06-12 19:01:45 +0200 |
---|---|---|
committer | Christoph Hellwig <hch@lst.de> | 2018-06-14 08:50:37 +0200 |
commit | cf65a0f6f6ff7631ba0ac0513a14ca5b65320d80 (patch) | |
tree | a81edcdf00e5a6e99fc2064fbcd9de4f33a4684f /kernel | |
parent | e37460c1ca08cf9d3b82eb3b6f205888d8d01182 (diff) |
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 <hch@lst.de>
Diffstat (limited to 'kernel')
-rw-r--r-- | kernel/Makefile | 1 | ||||
-rw-r--r-- | kernel/dma/Kconfig | 50 | ||||
-rw-r--r-- | kernel/dma/Makefile | 11 | ||||
-rw-r--r-- | kernel/dma/coherent.c | 434 | ||||
-rw-r--r-- | kernel/dma/contiguous.c | 278 | ||||
-rw-r--r-- | kernel/dma/debug.c | 1773 | ||||
-rw-r--r-- | kernel/dma/direct.c | 204 | ||||
-rw-r--r-- | kernel/dma/mapping.c | 345 | ||||
-rw-r--r-- | kernel/dma/noncoherent.c | 102 | ||||
-rw-r--r-- | kernel/dma/swiotlb.c | 1087 | ||||
-rw-r--r-- | kernel/dma/virt.c | 59 |
11 files changed, 4344 insertions, 0 deletions
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 <linux/io.h> +#include <linux/slab.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/dma-mapping.h> + +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 <linux/of.h> +#include <linux/of_fdt.h> +#include <linux/of_reserved_mem.h> + +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 <m.szyprowski@samsung.com> + * Michal Nazarewicz <mina86@mina86.com> + */ + +#define pr_fmt(fmt) "cma: " fmt + +#ifdef CONFIG_CMA_DEBUG +#ifndef DEBUG +# define DEBUG +#endif +#endif + +#include <asm/page.h> +#include <asm/dma-contiguous.h> + +#include <linux/memblock.h> +#include <linux/err.h> +#include <linux/sizes.h> +#include <linux/dma-contiguous.h> +#include <linux/cma.h> + +#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 <linux/of.h> +#include <linux/of_fdt.h> +#include <linux/of_reserved_mem.h> + +#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 <joerg.roedel@amd.com> + * + * 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 <linux/sched/task_stack.h> +#include <linux/scatterlist.h> +#include <linux/dma-mapping.h> +#include <linux/sched/task.h> +#include <linux/stacktrace.h> +#include <linux/dma-debug.h> +#include <linux/spinlock.h> +#include <linux/vmalloc.h> +#include <linux/debugfs.h> +#include <linux/uaccess.h> +#include <linux/export.h> +#include <linux/device.h> +#include <linux/types.h> +#include <linux/sched.h> +#include <linux/ctype.h> +#include <linux/list.h> +#include <linux/slab.h> + +#include <asm/sections.h> + +#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; |