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Diffstat (limited to '')
| -rw-r--r-- | kernel/dma/mapping.c | 345 |
1 files changed, 345 insertions, 0 deletions
diff --git a/kernel/dma/mapping.c b/kernel/dma/mapping.c new file mode 100644 index 000000000..d2a92ddaa --- /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 <teheo@suse.de> + */ + +#include <linux/acpi.h> +#include <linux/dma-mapping.h> +#include <linux/export.h> +#include <linux/gfp.h> +#include <linux/of_device.h> +#include <linux/slab.h> +#include <linux/vmalloc.h> + +/* + * 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); +} |