2 * drivers/base/dma-mapping.c - arch-independent dma-mapping routines
4 * Copyright (c) 2006 SUSE Linux Products GmbH
5 * Copyright (c) 2006 Tejun Heo <teheo@suse.de>
7 * This file is released under the GPLv2.
10 #include <linux/dma-mapping.h>
11 #include <linux/export.h>
12 #include <linux/gfp.h>
13 #include <linux/slab.h>
14 #include <linux/vmalloc.h>
22 dma_addr_t dma_handle;
25 static void dmam_coherent_release(struct device *dev, void *res)
27 struct dma_devres *this = res;
29 dma_free_coherent(dev, this->size, this->vaddr, this->dma_handle);
32 static void dmam_noncoherent_release(struct device *dev, void *res)
34 struct dma_devres *this = res;
36 dma_free_noncoherent(dev, this->size, this->vaddr, this->dma_handle);
39 static int dmam_match(struct device *dev, void *res, void *match_data)
41 struct dma_devres *this = res, *match = match_data;
43 if (this->vaddr == match->vaddr) {
44 WARN_ON(this->size != match->size ||
45 this->dma_handle != match->dma_handle);
52 * dmam_alloc_coherent - Managed dma_alloc_coherent()
53 * @dev: Device to allocate coherent memory for
54 * @size: Size of allocation
55 * @dma_handle: Out argument for allocated DMA handle
56 * @gfp: Allocation flags
58 * Managed dma_alloc_coherent(). Memory allocated using this function
59 * will be automatically released on driver detach.
62 * Pointer to allocated memory on success, NULL on failure.
64 void *dmam_alloc_coherent(struct device *dev, size_t size,
65 dma_addr_t *dma_handle, gfp_t gfp)
67 struct dma_devres *dr;
70 dr = devres_alloc(dmam_coherent_release, sizeof(*dr), gfp);
74 vaddr = dma_alloc_coherent(dev, size, dma_handle, gfp);
81 dr->dma_handle = *dma_handle;
88 EXPORT_SYMBOL(dmam_alloc_coherent);
91 * dmam_free_coherent - Managed dma_free_coherent()
92 * @dev: Device to free coherent memory for
93 * @size: Size of allocation
94 * @vaddr: Virtual address of the memory to free
95 * @dma_handle: DMA handle of the memory to free
97 * Managed dma_free_coherent().
99 void dmam_free_coherent(struct device *dev, size_t size, void *vaddr,
100 dma_addr_t dma_handle)
102 struct dma_devres match_data = { size, vaddr, dma_handle };
104 dma_free_coherent(dev, size, vaddr, dma_handle);
105 WARN_ON(devres_destroy(dev, dmam_coherent_release, dmam_match,
108 EXPORT_SYMBOL(dmam_free_coherent);
111 * dmam_alloc_non_coherent - Managed dma_alloc_non_coherent()
112 * @dev: Device to allocate non_coherent memory for
113 * @size: Size of allocation
114 * @dma_handle: Out argument for allocated DMA handle
115 * @gfp: Allocation flags
117 * Managed dma_alloc_non_coherent(). Memory allocated using this
118 * function will be automatically released on driver detach.
121 * Pointer to allocated memory on success, NULL on failure.
123 void *dmam_alloc_noncoherent(struct device *dev, size_t size,
124 dma_addr_t *dma_handle, gfp_t gfp)
126 struct dma_devres *dr;
129 dr = devres_alloc(dmam_noncoherent_release, sizeof(*dr), gfp);
133 vaddr = dma_alloc_noncoherent(dev, size, dma_handle, gfp);
140 dr->dma_handle = *dma_handle;
147 EXPORT_SYMBOL(dmam_alloc_noncoherent);
150 * dmam_free_coherent - Managed dma_free_noncoherent()
151 * @dev: Device to free noncoherent memory for
152 * @size: Size of allocation
153 * @vaddr: Virtual address of the memory to free
154 * @dma_handle: DMA handle of the memory to free
156 * Managed dma_free_noncoherent().
158 void dmam_free_noncoherent(struct device *dev, size_t size, void *vaddr,
159 dma_addr_t dma_handle)
161 struct dma_devres match_data = { size, vaddr, dma_handle };
163 dma_free_noncoherent(dev, size, vaddr, dma_handle);
164 WARN_ON(!devres_destroy(dev, dmam_noncoherent_release, dmam_match,
167 EXPORT_SYMBOL(dmam_free_noncoherent);
169 #ifdef CONFIG_HAVE_GENERIC_DMA_COHERENT
171 static void dmam_coherent_decl_release(struct device *dev, void *res)
173 dma_release_declared_memory(dev);
177 * dmam_declare_coherent_memory - Managed dma_declare_coherent_memory()
178 * @dev: Device to declare coherent memory for
179 * @phys_addr: Physical address of coherent memory to be declared
180 * @device_addr: Device address of coherent memory to be declared
181 * @size: Size of coherent memory to be declared
184 * Managed dma_declare_coherent_memory().
187 * 0 on success, -errno on failure.
189 int dmam_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr,
190 dma_addr_t device_addr, size_t size, int flags)
195 res = devres_alloc(dmam_coherent_decl_release, 0, GFP_KERNEL);
199 rc = dma_declare_coherent_memory(dev, phys_addr, device_addr, size,
202 devres_add(dev, res);
208 EXPORT_SYMBOL(dmam_declare_coherent_memory);
211 * dmam_release_declared_memory - Managed dma_release_declared_memory().
212 * @dev: Device to release declared coherent memory for
214 * Managed dmam_release_declared_memory().
216 void dmam_release_declared_memory(struct device *dev)
218 WARN_ON(devres_destroy(dev, dmam_coherent_decl_release, NULL, NULL));
220 EXPORT_SYMBOL(dmam_release_declared_memory);
225 * Create scatter-list for the already allocated DMA buffer.
227 int dma_common_get_sgtable(struct device *dev, struct sg_table *sgt,
228 void *cpu_addr, dma_addr_t handle, size_t size)
230 struct page *page = virt_to_page(cpu_addr);
233 ret = sg_alloc_table(sgt, 1, GFP_KERNEL);
237 sg_set_page(sgt->sgl, page, PAGE_ALIGN(size), 0);
240 EXPORT_SYMBOL(dma_common_get_sgtable);
243 * Create userspace mapping for the DMA-coherent memory.
245 int dma_common_mmap(struct device *dev, struct vm_area_struct *vma,
246 void *cpu_addr, dma_addr_t dma_addr, size_t size)
249 #if defined(CONFIG_MMU) && !defined(CONFIG_ARCH_NO_COHERENT_DMA_MMAP)
250 unsigned long user_count = (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
251 unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT;
252 unsigned long pfn = page_to_pfn(virt_to_page(cpu_addr));
253 unsigned long off = vma->vm_pgoff;
255 vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
257 if (dma_mmap_from_coherent(dev, vma, cpu_addr, size, &ret))
260 if (off < count && user_count <= (count - off)) {
261 ret = remap_pfn_range(vma, vma->vm_start,
263 user_count << PAGE_SHIFT,
266 #endif /* CONFIG_MMU && !CONFIG_ARCH_NO_COHERENT_DMA_MMAP */
270 EXPORT_SYMBOL(dma_common_mmap);
274 * remaps an array of PAGE_SIZE pages into another vm_area
275 * Cannot be used in non-sleeping contexts
277 void *dma_common_pages_remap(struct page **pages, size_t size,
278 unsigned long vm_flags, pgprot_t prot,
281 struct vm_struct *area;
283 area = get_vm_area_caller(size, vm_flags, caller);
289 if (map_vm_area(area, prot, pages)) {
298 * remaps an allocated contiguous region into another vm_area.
299 * Cannot be used in non-sleeping contexts
302 void *dma_common_contiguous_remap(struct page *page, size_t size,
303 unsigned long vm_flags,
304 pgprot_t prot, const void *caller)
311 pages = kmalloc(sizeof(struct page *) << get_order(size), GFP_KERNEL);
315 for (i = 0, pfn = page_to_pfn(page); i < (size >> PAGE_SHIFT); i++)
316 pages[i] = pfn_to_page(pfn + i);
318 ptr = dma_common_pages_remap(pages, size, vm_flags, prot, caller);
326 * unmaps a range previously mapped by dma_common_*_remap
328 void dma_common_free_remap(void *cpu_addr, size_t size, unsigned long vm_flags)
330 struct vm_struct *area = find_vm_area(cpu_addr);
332 if (!area || (area->flags & vm_flags) != vm_flags) {
333 WARN(1, "trying to free invalid coherent area: %p\n", cpu_addr);
337 unmap_kernel_range((unsigned long)cpu_addr, size);