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v3.1
  1/*
  2 * drivers/base/dma-mapping.c - arch-independent dma-mapping routines
  3 *
  4 * Copyright (c) 2006  SUSE Linux Products GmbH
  5 * Copyright (c) 2006  Tejun Heo <teheo@suse.de>
  6 *
  7 * This file is released under the GPLv2.
  8 */
  9
 10#include <linux/dma-mapping.h>
 
 11#include <linux/gfp.h>
 
 
 12
 13/*
 14 * Managed DMA API
 15 */
 16struct dma_devres {
 17	size_t		size;
 18	void		*vaddr;
 19	dma_addr_t	dma_handle;
 20};
 21
 22static void dmam_coherent_release(struct device *dev, void *res)
 23{
 24	struct dma_devres *this = res;
 25
 26	dma_free_coherent(dev, this->size, this->vaddr, this->dma_handle);
 27}
 28
 29static void dmam_noncoherent_release(struct device *dev, void *res)
 30{
 31	struct dma_devres *this = res;
 32
 33	dma_free_noncoherent(dev, this->size, this->vaddr, this->dma_handle);
 34}
 35
 36static int dmam_match(struct device *dev, void *res, void *match_data)
 37{
 38	struct dma_devres *this = res, *match = match_data;
 39
 40	if (this->vaddr == match->vaddr) {
 41		WARN_ON(this->size != match->size ||
 42			this->dma_handle != match->dma_handle);
 43		return 1;
 44	}
 45	return 0;
 46}
 47
 48/**
 49 * dmam_alloc_coherent - Managed dma_alloc_coherent()
 50 * @dev: Device to allocate coherent memory for
 51 * @size: Size of allocation
 52 * @dma_handle: Out argument for allocated DMA handle
 53 * @gfp: Allocation flags
 54 *
 55 * Managed dma_alloc_coherent().  Memory allocated using this function
 56 * will be automatically released on driver detach.
 57 *
 58 * RETURNS:
 59 * Pointer to allocated memory on success, NULL on failure.
 60 */
 61void * dmam_alloc_coherent(struct device *dev, size_t size,
 62			   dma_addr_t *dma_handle, gfp_t gfp)
 63{
 64	struct dma_devres *dr;
 65	void *vaddr;
 66
 67	dr = devres_alloc(dmam_coherent_release, sizeof(*dr), gfp);
 68	if (!dr)
 69		return NULL;
 70
 71	vaddr = dma_alloc_coherent(dev, size, dma_handle, gfp);
 72	if (!vaddr) {
 73		devres_free(dr);
 74		return NULL;
 75	}
 76
 77	dr->vaddr = vaddr;
 78	dr->dma_handle = *dma_handle;
 79	dr->size = size;
 80
 81	devres_add(dev, dr);
 82
 83	return vaddr;
 84}
 85EXPORT_SYMBOL(dmam_alloc_coherent);
 86
 87/**
 88 * dmam_free_coherent - Managed dma_free_coherent()
 89 * @dev: Device to free coherent memory for
 90 * @size: Size of allocation
 91 * @vaddr: Virtual address of the memory to free
 92 * @dma_handle: DMA handle of the memory to free
 93 *
 94 * Managed dma_free_coherent().
 95 */
 96void dmam_free_coherent(struct device *dev, size_t size, void *vaddr,
 97			dma_addr_t dma_handle)
 98{
 99	struct dma_devres match_data = { size, vaddr, dma_handle };
100
101	dma_free_coherent(dev, size, vaddr, dma_handle);
102	WARN_ON(devres_destroy(dev, dmam_coherent_release, dmam_match,
103			       &match_data));
104}
105EXPORT_SYMBOL(dmam_free_coherent);
106
107/**
108 * dmam_alloc_non_coherent - Managed dma_alloc_non_coherent()
109 * @dev: Device to allocate non_coherent memory for
110 * @size: Size of allocation
111 * @dma_handle: Out argument for allocated DMA handle
112 * @gfp: Allocation flags
113 *
114 * Managed dma_alloc_non_coherent().  Memory allocated using this
115 * function will be automatically released on driver detach.
116 *
117 * RETURNS:
118 * Pointer to allocated memory on success, NULL on failure.
119 */
120void *dmam_alloc_noncoherent(struct device *dev, size_t size,
121			     dma_addr_t *dma_handle, gfp_t gfp)
122{
123	struct dma_devres *dr;
124	void *vaddr;
125
126	dr = devres_alloc(dmam_noncoherent_release, sizeof(*dr), gfp);
127	if (!dr)
128		return NULL;
129
130	vaddr = dma_alloc_noncoherent(dev, size, dma_handle, gfp);
131	if (!vaddr) {
132		devres_free(dr);
133		return NULL;
134	}
135
136	dr->vaddr = vaddr;
137	dr->dma_handle = *dma_handle;
138	dr->size = size;
139
140	devres_add(dev, dr);
141
142	return vaddr;
143}
144EXPORT_SYMBOL(dmam_alloc_noncoherent);
145
146/**
147 * dmam_free_coherent - Managed dma_free_noncoherent()
148 * @dev: Device to free noncoherent memory for
149 * @size: Size of allocation
150 * @vaddr: Virtual address of the memory to free
151 * @dma_handle: DMA handle of the memory to free
152 *
153 * Managed dma_free_noncoherent().
154 */
155void dmam_free_noncoherent(struct device *dev, size_t size, void *vaddr,
156			   dma_addr_t dma_handle)
157{
158	struct dma_devres match_data = { size, vaddr, dma_handle };
159
160	dma_free_noncoherent(dev, size, vaddr, dma_handle);
161	WARN_ON(!devres_destroy(dev, dmam_noncoherent_release, dmam_match,
162				&match_data));
163}
164EXPORT_SYMBOL(dmam_free_noncoherent);
165
166#ifdef ARCH_HAS_DMA_DECLARE_COHERENT_MEMORY
167
168static void dmam_coherent_decl_release(struct device *dev, void *res)
169{
170	dma_release_declared_memory(dev);
171}
172
173/**
174 * dmam_declare_coherent_memory - Managed dma_declare_coherent_memory()
175 * @dev: Device to declare coherent memory for
176 * @bus_addr: Bus address of coherent memory to be declared
177 * @device_addr: Device address of coherent memory to be declared
178 * @size: Size of coherent memory to be declared
179 * @flags: Flags
180 *
181 * Managed dma_declare_coherent_memory().
182 *
183 * RETURNS:
184 * 0 on success, -errno on failure.
185 */
186int dmam_declare_coherent_memory(struct device *dev, dma_addr_t bus_addr,
187				 dma_addr_t device_addr, size_t size, int flags)
188{
189	void *res;
190	int rc;
191
192	res = devres_alloc(dmam_coherent_decl_release, 0, GFP_KERNEL);
193	if (!res)
194		return -ENOMEM;
195
196	rc = dma_declare_coherent_memory(dev, bus_addr, device_addr, size,
197					 flags);
198	if (rc == 0)
199		devres_add(dev, res);
200	else
201		devres_free(res);
202
203	return rc;
204}
205EXPORT_SYMBOL(dmam_declare_coherent_memory);
206
207/**
208 * dmam_release_declared_memory - Managed dma_release_declared_memory().
209 * @dev: Device to release declared coherent memory for
210 *
211 * Managed dmam_release_declared_memory().
212 */
213void dmam_release_declared_memory(struct device *dev)
214{
215	WARN_ON(devres_destroy(dev, dmam_coherent_decl_release, NULL, NULL));
216}
217EXPORT_SYMBOL(dmam_release_declared_memory);
218
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
219#endif
v4.6
  1/*
  2 * drivers/base/dma-mapping.c - arch-independent dma-mapping routines
  3 *
  4 * Copyright (c) 2006  SUSE Linux Products GmbH
  5 * Copyright (c) 2006  Tejun Heo <teheo@suse.de>
  6 *
  7 * This file is released under the GPLv2.
  8 */
  9
 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>
 15
 16/*
 17 * Managed DMA API
 18 */
 19struct dma_devres {
 20	size_t		size;
 21	void		*vaddr;
 22	dma_addr_t	dma_handle;
 23};
 24
 25static void dmam_coherent_release(struct device *dev, void *res)
 26{
 27	struct dma_devres *this = res;
 28
 29	dma_free_coherent(dev, this->size, this->vaddr, this->dma_handle);
 30}
 31
 32static void dmam_noncoherent_release(struct device *dev, void *res)
 33{
 34	struct dma_devres *this = res;
 35
 36	dma_free_noncoherent(dev, this->size, this->vaddr, this->dma_handle);
 37}
 38
 39static int dmam_match(struct device *dev, void *res, void *match_data)
 40{
 41	struct dma_devres *this = res, *match = match_data;
 42
 43	if (this->vaddr == match->vaddr) {
 44		WARN_ON(this->size != match->size ||
 45			this->dma_handle != match->dma_handle);
 46		return 1;
 47	}
 48	return 0;
 49}
 50
 51/**
 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
 57 *
 58 * Managed dma_alloc_coherent().  Memory allocated using this function
 59 * will be automatically released on driver detach.
 60 *
 61 * RETURNS:
 62 * Pointer to allocated memory on success, NULL on failure.
 63 */
 64void *dmam_alloc_coherent(struct device *dev, size_t size,
 65			   dma_addr_t *dma_handle, gfp_t gfp)
 66{
 67	struct dma_devres *dr;
 68	void *vaddr;
 69
 70	dr = devres_alloc(dmam_coherent_release, sizeof(*dr), gfp);
 71	if (!dr)
 72		return NULL;
 73
 74	vaddr = dma_alloc_coherent(dev, size, dma_handle, gfp);
 75	if (!vaddr) {
 76		devres_free(dr);
 77		return NULL;
 78	}
 79
 80	dr->vaddr = vaddr;
 81	dr->dma_handle = *dma_handle;
 82	dr->size = size;
 83
 84	devres_add(dev, dr);
 85
 86	return vaddr;
 87}
 88EXPORT_SYMBOL(dmam_alloc_coherent);
 89
 90/**
 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
 96 *
 97 * Managed dma_free_coherent().
 98 */
 99void dmam_free_coherent(struct device *dev, size_t size, void *vaddr,
100			dma_addr_t dma_handle)
101{
102	struct dma_devres match_data = { size, vaddr, dma_handle };
103
104	dma_free_coherent(dev, size, vaddr, dma_handle);
105	WARN_ON(devres_destroy(dev, dmam_coherent_release, dmam_match,
106			       &match_data));
107}
108EXPORT_SYMBOL(dmam_free_coherent);
109
110/**
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
116 *
117 * Managed dma_alloc_non_coherent().  Memory allocated using this
118 * function will be automatically released on driver detach.
119 *
120 * RETURNS:
121 * Pointer to allocated memory on success, NULL on failure.
122 */
123void *dmam_alloc_noncoherent(struct device *dev, size_t size,
124			     dma_addr_t *dma_handle, gfp_t gfp)
125{
126	struct dma_devres *dr;
127	void *vaddr;
128
129	dr = devres_alloc(dmam_noncoherent_release, sizeof(*dr), gfp);
130	if (!dr)
131		return NULL;
132
133	vaddr = dma_alloc_noncoherent(dev, size, dma_handle, gfp);
134	if (!vaddr) {
135		devres_free(dr);
136		return NULL;
137	}
138
139	dr->vaddr = vaddr;
140	dr->dma_handle = *dma_handle;
141	dr->size = size;
142
143	devres_add(dev, dr);
144
145	return vaddr;
146}
147EXPORT_SYMBOL(dmam_alloc_noncoherent);
148
149/**
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
155 *
156 * Managed dma_free_noncoherent().
157 */
158void dmam_free_noncoherent(struct device *dev, size_t size, void *vaddr,
159			   dma_addr_t dma_handle)
160{
161	struct dma_devres match_data = { size, vaddr, dma_handle };
162
163	dma_free_noncoherent(dev, size, vaddr, dma_handle);
164	WARN_ON(!devres_destroy(dev, dmam_noncoherent_release, dmam_match,
165				&match_data));
166}
167EXPORT_SYMBOL(dmam_free_noncoherent);
168
169#ifdef CONFIG_HAVE_GENERIC_DMA_COHERENT
170
171static void dmam_coherent_decl_release(struct device *dev, void *res)
172{
173	dma_release_declared_memory(dev);
174}
175
176/**
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
182 * @flags: Flags
183 *
184 * Managed dma_declare_coherent_memory().
185 *
186 * RETURNS:
187 * 0 on success, -errno on failure.
188 */
189int dmam_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr,
190				 dma_addr_t device_addr, size_t size, int flags)
191{
192	void *res;
193	int rc;
194
195	res = devres_alloc(dmam_coherent_decl_release, 0, GFP_KERNEL);
196	if (!res)
197		return -ENOMEM;
198
199	rc = dma_declare_coherent_memory(dev, phys_addr, device_addr, size,
200					 flags);
201	if (rc == 0)
202		devres_add(dev, res);
203	else
204		devres_free(res);
205
206	return rc;
207}
208EXPORT_SYMBOL(dmam_declare_coherent_memory);
209
210/**
211 * dmam_release_declared_memory - Managed dma_release_declared_memory().
212 * @dev: Device to release declared coherent memory for
213 *
214 * Managed dmam_release_declared_memory().
215 */
216void dmam_release_declared_memory(struct device *dev)
217{
218	WARN_ON(devres_destroy(dev, dmam_coherent_decl_release, NULL, NULL));
219}
220EXPORT_SYMBOL(dmam_release_declared_memory);
221
222#endif
223
224/*
225 * Create scatter-list for the already allocated DMA buffer.
226 */
227int dma_common_get_sgtable(struct device *dev, struct sg_table *sgt,
228		 void *cpu_addr, dma_addr_t handle, size_t size)
229{
230	struct page *page = virt_to_page(cpu_addr);
231	int ret;
232
233	ret = sg_alloc_table(sgt, 1, GFP_KERNEL);
234	if (unlikely(ret))
235		return ret;
236
237	sg_set_page(sgt->sgl, page, PAGE_ALIGN(size), 0);
238	return 0;
239}
240EXPORT_SYMBOL(dma_common_get_sgtable);
241
242/*
243 * Create userspace mapping for the DMA-coherent memory.
244 */
245int dma_common_mmap(struct device *dev, struct vm_area_struct *vma,
246		    void *cpu_addr, dma_addr_t dma_addr, size_t size)
247{
248	int ret = -ENXIO;
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;
254
255	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
256
257	if (dma_mmap_from_coherent(dev, vma, cpu_addr, size, &ret))
258		return ret;
259
260	if (off < count && user_count <= (count - off)) {
261		ret = remap_pfn_range(vma, vma->vm_start,
262				      pfn + off,
263				      user_count << PAGE_SHIFT,
264				      vma->vm_page_prot);
265	}
266#endif	/* CONFIG_MMU && !CONFIG_ARCH_NO_COHERENT_DMA_MMAP */
267
268	return ret;
269}
270EXPORT_SYMBOL(dma_common_mmap);
271
272#ifdef CONFIG_MMU
273/*
274 * remaps an array of PAGE_SIZE pages into another vm_area
275 * Cannot be used in non-sleeping contexts
276 */
277void *dma_common_pages_remap(struct page **pages, size_t size,
278			unsigned long vm_flags, pgprot_t prot,
279			const void *caller)
280{
281	struct vm_struct *area;
282
283	area = get_vm_area_caller(size, vm_flags, caller);
284	if (!area)
285		return NULL;
286
287	area->pages = pages;
288
289	if (map_vm_area(area, prot, pages)) {
290		vunmap(area->addr);
291		return NULL;
292	}
293
294	return area->addr;
295}
296
297/*
298 * remaps an allocated contiguous region into another vm_area.
299 * Cannot be used in non-sleeping contexts
300 */
301
302void *dma_common_contiguous_remap(struct page *page, size_t size,
303			unsigned long vm_flags,
304			pgprot_t prot, const void *caller)
305{
306	int i;
307	struct page **pages;
308	void *ptr;
309	unsigned long pfn;
310
311	pages = kmalloc(sizeof(struct page *) << get_order(size), GFP_KERNEL);
312	if (!pages)
313		return NULL;
314
315	for (i = 0, pfn = page_to_pfn(page); i < (size >> PAGE_SHIFT); i++)
316		pages[i] = pfn_to_page(pfn + i);
317
318	ptr = dma_common_pages_remap(pages, size, vm_flags, prot, caller);
319
320	kfree(pages);
321
322	return ptr;
323}
324
325/*
326 * unmaps a range previously mapped by dma_common_*_remap
327 */
328void dma_common_free_remap(void *cpu_addr, size_t size, unsigned long vm_flags)
329{
330	struct vm_struct *area = find_vm_area(cpu_addr);
331
332	if (!area || (area->flags & vm_flags) != vm_flags) {
333		WARN(1, "trying to free invalid coherent area: %p\n", cpu_addr);
334		return;
335	}
336
337	unmap_kernel_range((unsigned long)cpu_addr, size);
338	vunmap(cpu_addr);
339}
340#endif