| /* |
| * drivers/base/dma-mapping.c - arch-independent dma-mapping routines |
| * |
| * Copyright (c) 2006 SUSE Linux Products GmbH |
| * Copyright (c) 2006 Tejun Heo <teheo@suse.de> |
| * |
| * This file is released under the GPLv2. |
| */ |
| |
| #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); |
| rc = 0; |
| } else { |
| devres_free(res); |
| rc = -ENOMEM; |
| } |
| |
| 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 pfn = page_to_pfn(virt_to_page(cpu_addr)); |
| 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, |
| pfn + 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 |
| |
| /* |
| * Common configuration to enable DMA API use for a device |
| */ |
| #include <linux/pci.h> |
| |
| int dma_configure(struct device *dev) |
| { |
| struct device *bridge = NULL, *dma_dev = dev; |
| enum dev_dma_attr attr; |
| int ret = 0; |
| |
| if (dev_is_pci(dev)) { |
| bridge = pci_get_host_bridge_device(to_pci_dev(dev)); |
| dma_dev = bridge; |
| if (IS_ENABLED(CONFIG_OF) && dma_dev->parent && |
| dma_dev->parent->of_node) |
| dma_dev = dma_dev->parent; |
| } |
| |
| if (dma_dev->of_node) { |
| ret = of_dma_configure(dev, dma_dev->of_node); |
| } else if (has_acpi_companion(dma_dev)) { |
| attr = acpi_get_dma_attr(to_acpi_device_node(dma_dev->fwnode)); |
| if (attr != DEV_DMA_NOT_SUPPORTED) |
| ret = acpi_dma_configure(dev, attr); |
| } |
| |
| if (bridge) |
| pci_put_host_bridge_device(bridge); |
| |
| return ret; |
| } |
| |
| void dma_deconfigure(struct device *dev) |
| { |
| of_dma_deconfigure(dev); |
| acpi_dma_deconfigure(dev); |
| } |