xref: /linux-6.15/include/linux/dma-mapping.h (revision fffe3cc8)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _LINUX_DMA_MAPPING_H
3 #define _LINUX_DMA_MAPPING_H
4 
5 #include <linux/sizes.h>
6 #include <linux/string.h>
7 #include <linux/device.h>
8 #include <linux/err.h>
9 #include <linux/dma-direction.h>
10 #include <linux/scatterlist.h>
11 #include <linux/bug.h>
12 #include <linux/mem_encrypt.h>
13 
14 /**
15  * List of possible attributes associated with a DMA mapping. The semantics
16  * of each attribute should be defined in Documentation/core-api/dma-attributes.rst.
17  */
18 
19 /*
20  * DMA_ATTR_WEAK_ORDERING: Specifies that reads and writes to the mapping
21  * may be weakly ordered, that is that reads and writes may pass each other.
22  */
23 #define DMA_ATTR_WEAK_ORDERING		(1UL << 1)
24 /*
25  * DMA_ATTR_WRITE_COMBINE: Specifies that writes to the mapping may be
26  * buffered to improve performance.
27  */
28 #define DMA_ATTR_WRITE_COMBINE		(1UL << 2)
29 /*
30  * DMA_ATTR_NO_KERNEL_MAPPING: Lets the platform to avoid creating a kernel
31  * virtual mapping for the allocated buffer.
32  */
33 #define DMA_ATTR_NO_KERNEL_MAPPING	(1UL << 4)
34 /*
35  * DMA_ATTR_SKIP_CPU_SYNC: Allows platform code to skip synchronization of
36  * the CPU cache for the given buffer assuming that it has been already
37  * transferred to 'device' domain.
38  */
39 #define DMA_ATTR_SKIP_CPU_SYNC		(1UL << 5)
40 /*
41  * DMA_ATTR_FORCE_CONTIGUOUS: Forces contiguous allocation of the buffer
42  * in physical memory.
43  */
44 #define DMA_ATTR_FORCE_CONTIGUOUS	(1UL << 6)
45 /*
46  * DMA_ATTR_ALLOC_SINGLE_PAGES: This is a hint to the DMA-mapping subsystem
47  * that it's probably not worth the time to try to allocate memory to in a way
48  * that gives better TLB efficiency.
49  */
50 #define DMA_ATTR_ALLOC_SINGLE_PAGES	(1UL << 7)
51 /*
52  * DMA_ATTR_NO_WARN: This tells the DMA-mapping subsystem to suppress
53  * allocation failure reports (similarly to __GFP_NOWARN).
54  */
55 #define DMA_ATTR_NO_WARN	(1UL << 8)
56 
57 /*
58  * DMA_ATTR_PRIVILEGED: used to indicate that the buffer is fully
59  * accessible at an elevated privilege level (and ideally inaccessible or
60  * at least read-only at lesser-privileged levels).
61  */
62 #define DMA_ATTR_PRIVILEGED		(1UL << 9)
63 
64 /*
65  * A dma_addr_t can hold any valid DMA or bus address for the platform.  It can
66  * be given to a device to use as a DMA source or target.  It is specific to a
67  * given device and there may be a translation between the CPU physical address
68  * space and the bus address space.
69  *
70  * DMA_MAPPING_ERROR is the magic error code if a mapping failed.  It should not
71  * be used directly in drivers, but checked for using dma_mapping_error()
72  * instead.
73  */
74 #define DMA_MAPPING_ERROR		(~(dma_addr_t)0)
75 
76 #define DMA_BIT_MASK(n)	(((n) == 64) ? ~0ULL : ((1ULL<<(n))-1))
77 
78 #ifdef CONFIG_DMA_API_DEBUG
79 void debug_dma_mapping_error(struct device *dev, dma_addr_t dma_addr);
80 void debug_dma_map_single(struct device *dev, const void *addr,
81 		unsigned long len);
82 #else
83 static inline void debug_dma_mapping_error(struct device *dev,
84 		dma_addr_t dma_addr)
85 {
86 }
87 static inline void debug_dma_map_single(struct device *dev, const void *addr,
88 		unsigned long len)
89 {
90 }
91 #endif /* CONFIG_DMA_API_DEBUG */
92 
93 #ifdef CONFIG_HAS_DMA
94 static inline int dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
95 {
96 	debug_dma_mapping_error(dev, dma_addr);
97 
98 	if (unlikely(dma_addr == DMA_MAPPING_ERROR))
99 		return -ENOMEM;
100 	return 0;
101 }
102 
103 dma_addr_t dma_map_page_attrs(struct device *dev, struct page *page,
104 		size_t offset, size_t size, enum dma_data_direction dir,
105 		unsigned long attrs);
106 void dma_unmap_page_attrs(struct device *dev, dma_addr_t addr, size_t size,
107 		enum dma_data_direction dir, unsigned long attrs);
108 int dma_map_sg_attrs(struct device *dev, struct scatterlist *sg, int nents,
109 		enum dma_data_direction dir, unsigned long attrs);
110 void dma_unmap_sg_attrs(struct device *dev, struct scatterlist *sg,
111 				      int nents, enum dma_data_direction dir,
112 				      unsigned long attrs);
113 int dma_map_sgtable(struct device *dev, struct sg_table *sgt,
114 		enum dma_data_direction dir, unsigned long attrs);
115 dma_addr_t dma_map_resource(struct device *dev, phys_addr_t phys_addr,
116 		size_t size, enum dma_data_direction dir, unsigned long attrs);
117 void dma_unmap_resource(struct device *dev, dma_addr_t addr, size_t size,
118 		enum dma_data_direction dir, unsigned long attrs);
119 void dma_sync_single_for_cpu(struct device *dev, dma_addr_t addr, size_t size,
120 		enum dma_data_direction dir);
121 void dma_sync_single_for_device(struct device *dev, dma_addr_t addr,
122 		size_t size, enum dma_data_direction dir);
123 void dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg,
124 		    int nelems, enum dma_data_direction dir);
125 void dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg,
126 		       int nelems, enum dma_data_direction dir);
127 void *dma_alloc_attrs(struct device *dev, size_t size, dma_addr_t *dma_handle,
128 		gfp_t flag, unsigned long attrs);
129 void dma_free_attrs(struct device *dev, size_t size, void *cpu_addr,
130 		dma_addr_t dma_handle, unsigned long attrs);
131 void *dmam_alloc_attrs(struct device *dev, size_t size, dma_addr_t *dma_handle,
132 		gfp_t gfp, unsigned long attrs);
133 void dmam_free_coherent(struct device *dev, size_t size, void *vaddr,
134 		dma_addr_t dma_handle);
135 int dma_get_sgtable_attrs(struct device *dev, struct sg_table *sgt,
136 		void *cpu_addr, dma_addr_t dma_addr, size_t size,
137 		unsigned long attrs);
138 int dma_mmap_attrs(struct device *dev, struct vm_area_struct *vma,
139 		void *cpu_addr, dma_addr_t dma_addr, size_t size,
140 		unsigned long attrs);
141 bool dma_can_mmap(struct device *dev);
142 int dma_supported(struct device *dev, u64 mask);
143 int dma_set_mask(struct device *dev, u64 mask);
144 int dma_set_coherent_mask(struct device *dev, u64 mask);
145 u64 dma_get_required_mask(struct device *dev);
146 size_t dma_max_mapping_size(struct device *dev);
147 bool dma_need_sync(struct device *dev, dma_addr_t dma_addr);
148 unsigned long dma_get_merge_boundary(struct device *dev);
149 struct sg_table *dma_alloc_noncontiguous(struct device *dev, size_t size,
150 		enum dma_data_direction dir, gfp_t gfp, unsigned long attrs);
151 void dma_free_noncontiguous(struct device *dev, size_t size,
152 		struct sg_table *sgt, enum dma_data_direction dir);
153 void *dma_vmap_noncontiguous(struct device *dev, size_t size,
154 		struct sg_table *sgt);
155 void dma_vunmap_noncontiguous(struct device *dev, void *vaddr);
156 int dma_mmap_noncontiguous(struct device *dev, struct vm_area_struct *vma,
157 		size_t size, struct sg_table *sgt);
158 #else /* CONFIG_HAS_DMA */
159 static inline dma_addr_t dma_map_page_attrs(struct device *dev,
160 		struct page *page, size_t offset, size_t size,
161 		enum dma_data_direction dir, unsigned long attrs)
162 {
163 	return DMA_MAPPING_ERROR;
164 }
165 static inline void dma_unmap_page_attrs(struct device *dev, dma_addr_t addr,
166 		size_t size, enum dma_data_direction dir, unsigned long attrs)
167 {
168 }
169 static inline int dma_map_sg_attrs(struct device *dev, struct scatterlist *sg,
170 		int nents, enum dma_data_direction dir, unsigned long attrs)
171 {
172 	return 0;
173 }
174 static inline void dma_unmap_sg_attrs(struct device *dev,
175 		struct scatterlist *sg, int nents, enum dma_data_direction dir,
176 		unsigned long attrs)
177 {
178 }
179 static inline int dma_map_sgtable(struct device *dev, struct sg_table *sgt,
180 		enum dma_data_direction dir, unsigned long attrs)
181 {
182 	return -EOPNOTSUPP;
183 }
184 static inline dma_addr_t dma_map_resource(struct device *dev,
185 		phys_addr_t phys_addr, size_t size, enum dma_data_direction dir,
186 		unsigned long attrs)
187 {
188 	return DMA_MAPPING_ERROR;
189 }
190 static inline void dma_unmap_resource(struct device *dev, dma_addr_t addr,
191 		size_t size, enum dma_data_direction dir, unsigned long attrs)
192 {
193 }
194 static inline void dma_sync_single_for_cpu(struct device *dev, dma_addr_t addr,
195 		size_t size, enum dma_data_direction dir)
196 {
197 }
198 static inline void dma_sync_single_for_device(struct device *dev,
199 		dma_addr_t addr, size_t size, enum dma_data_direction dir)
200 {
201 }
202 static inline void dma_sync_sg_for_cpu(struct device *dev,
203 		struct scatterlist *sg, int nelems, enum dma_data_direction dir)
204 {
205 }
206 static inline void dma_sync_sg_for_device(struct device *dev,
207 		struct scatterlist *sg, int nelems, enum dma_data_direction dir)
208 {
209 }
210 static inline int dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
211 {
212 	return -ENOMEM;
213 }
214 static inline void *dma_alloc_attrs(struct device *dev, size_t size,
215 		dma_addr_t *dma_handle, gfp_t flag, unsigned long attrs)
216 {
217 	return NULL;
218 }
219 static void dma_free_attrs(struct device *dev, size_t size, void *cpu_addr,
220 		dma_addr_t dma_handle, unsigned long attrs)
221 {
222 }
223 static inline void *dmam_alloc_attrs(struct device *dev, size_t size,
224 		dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
225 {
226 	return NULL;
227 }
228 static inline void dmam_free_coherent(struct device *dev, size_t size,
229 		void *vaddr, dma_addr_t dma_handle)
230 {
231 }
232 static inline int dma_get_sgtable_attrs(struct device *dev,
233 		struct sg_table *sgt, void *cpu_addr, dma_addr_t dma_addr,
234 		size_t size, unsigned long attrs)
235 {
236 	return -ENXIO;
237 }
238 static inline int dma_mmap_attrs(struct device *dev, struct vm_area_struct *vma,
239 		void *cpu_addr, dma_addr_t dma_addr, size_t size,
240 		unsigned long attrs)
241 {
242 	return -ENXIO;
243 }
244 static inline bool dma_can_mmap(struct device *dev)
245 {
246 	return false;
247 }
248 static inline int dma_supported(struct device *dev, u64 mask)
249 {
250 	return 0;
251 }
252 static inline int dma_set_mask(struct device *dev, u64 mask)
253 {
254 	return -EIO;
255 }
256 static inline int dma_set_coherent_mask(struct device *dev, u64 mask)
257 {
258 	return -EIO;
259 }
260 static inline u64 dma_get_required_mask(struct device *dev)
261 {
262 	return 0;
263 }
264 static inline size_t dma_max_mapping_size(struct device *dev)
265 {
266 	return 0;
267 }
268 static inline bool dma_need_sync(struct device *dev, dma_addr_t dma_addr)
269 {
270 	return false;
271 }
272 static inline unsigned long dma_get_merge_boundary(struct device *dev)
273 {
274 	return 0;
275 }
276 static inline struct sg_table *dma_alloc_noncontiguous(struct device *dev,
277 		size_t size, enum dma_data_direction dir, gfp_t gfp,
278 		unsigned long attrs)
279 {
280 	return NULL;
281 }
282 static inline void dma_free_noncontiguous(struct device *dev, size_t size,
283 		struct sg_table *sgt, enum dma_data_direction dir)
284 {
285 }
286 static inline void *dma_vmap_noncontiguous(struct device *dev, size_t size,
287 		struct sg_table *sgt)
288 {
289 	return NULL;
290 }
291 static inline void dma_vunmap_noncontiguous(struct device *dev, void *vaddr)
292 {
293 }
294 static inline int dma_mmap_noncontiguous(struct device *dev,
295 		struct vm_area_struct *vma, size_t size, struct sg_table *sgt)
296 {
297 	return -EINVAL;
298 }
299 #endif /* CONFIG_HAS_DMA */
300 
301 struct page *dma_alloc_pages(struct device *dev, size_t size,
302 		dma_addr_t *dma_handle, enum dma_data_direction dir, gfp_t gfp);
303 void dma_free_pages(struct device *dev, size_t size, struct page *page,
304 		dma_addr_t dma_handle, enum dma_data_direction dir);
305 int dma_mmap_pages(struct device *dev, struct vm_area_struct *vma,
306 		size_t size, struct page *page);
307 
308 static inline void *dma_alloc_noncoherent(struct device *dev, size_t size,
309 		dma_addr_t *dma_handle, enum dma_data_direction dir, gfp_t gfp)
310 {
311 	struct page *page = dma_alloc_pages(dev, size, dma_handle, dir, gfp);
312 	return page ? page_address(page) : NULL;
313 }
314 
315 static inline void dma_free_noncoherent(struct device *dev, size_t size,
316 		void *vaddr, dma_addr_t dma_handle, enum dma_data_direction dir)
317 {
318 	dma_free_pages(dev, size, virt_to_page(vaddr), dma_handle, dir);
319 }
320 
321 static inline dma_addr_t dma_map_single_attrs(struct device *dev, void *ptr,
322 		size_t size, enum dma_data_direction dir, unsigned long attrs)
323 {
324 	/* DMA must never operate on areas that might be remapped. */
325 	if (dev_WARN_ONCE(dev, is_vmalloc_addr(ptr),
326 			  "rejecting DMA map of vmalloc memory\n"))
327 		return DMA_MAPPING_ERROR;
328 	debug_dma_map_single(dev, ptr, size);
329 	return dma_map_page_attrs(dev, virt_to_page(ptr), offset_in_page(ptr),
330 			size, dir, attrs);
331 }
332 
333 static inline void dma_unmap_single_attrs(struct device *dev, dma_addr_t addr,
334 		size_t size, enum dma_data_direction dir, unsigned long attrs)
335 {
336 	return dma_unmap_page_attrs(dev, addr, size, dir, attrs);
337 }
338 
339 static inline void dma_sync_single_range_for_cpu(struct device *dev,
340 		dma_addr_t addr, unsigned long offset, size_t size,
341 		enum dma_data_direction dir)
342 {
343 	return dma_sync_single_for_cpu(dev, addr + offset, size, dir);
344 }
345 
346 static inline void dma_sync_single_range_for_device(struct device *dev,
347 		dma_addr_t addr, unsigned long offset, size_t size,
348 		enum dma_data_direction dir)
349 {
350 	return dma_sync_single_for_device(dev, addr + offset, size, dir);
351 }
352 
353 /**
354  * dma_unmap_sgtable - Unmap the given buffer for DMA
355  * @dev:	The device for which to perform the DMA operation
356  * @sgt:	The sg_table object describing the buffer
357  * @dir:	DMA direction
358  * @attrs:	Optional DMA attributes for the unmap operation
359  *
360  * Unmaps a buffer described by a scatterlist stored in the given sg_table
361  * object for the @dir DMA operation by the @dev device. After this function
362  * the ownership of the buffer is transferred back to the CPU domain.
363  */
364 static inline void dma_unmap_sgtable(struct device *dev, struct sg_table *sgt,
365 		enum dma_data_direction dir, unsigned long attrs)
366 {
367 	dma_unmap_sg_attrs(dev, sgt->sgl, sgt->orig_nents, dir, attrs);
368 }
369 
370 /**
371  * dma_sync_sgtable_for_cpu - Synchronize the given buffer for CPU access
372  * @dev:	The device for which to perform the DMA operation
373  * @sgt:	The sg_table object describing the buffer
374  * @dir:	DMA direction
375  *
376  * Performs the needed cache synchronization and moves the ownership of the
377  * buffer back to the CPU domain, so it is safe to perform any access to it
378  * by the CPU. Before doing any further DMA operations, one has to transfer
379  * the ownership of the buffer back to the DMA domain by calling the
380  * dma_sync_sgtable_for_device().
381  */
382 static inline void dma_sync_sgtable_for_cpu(struct device *dev,
383 		struct sg_table *sgt, enum dma_data_direction dir)
384 {
385 	dma_sync_sg_for_cpu(dev, sgt->sgl, sgt->orig_nents, dir);
386 }
387 
388 /**
389  * dma_sync_sgtable_for_device - Synchronize the given buffer for DMA
390  * @dev:	The device for which to perform the DMA operation
391  * @sgt:	The sg_table object describing the buffer
392  * @dir:	DMA direction
393  *
394  * Performs the needed cache synchronization and moves the ownership of the
395  * buffer back to the DMA domain, so it is safe to perform the DMA operation.
396  * Once finished, one has to call dma_sync_sgtable_for_cpu() or
397  * dma_unmap_sgtable().
398  */
399 static inline void dma_sync_sgtable_for_device(struct device *dev,
400 		struct sg_table *sgt, enum dma_data_direction dir)
401 {
402 	dma_sync_sg_for_device(dev, sgt->sgl, sgt->orig_nents, dir);
403 }
404 
405 #define dma_map_single(d, a, s, r) dma_map_single_attrs(d, a, s, r, 0)
406 #define dma_unmap_single(d, a, s, r) dma_unmap_single_attrs(d, a, s, r, 0)
407 #define dma_map_sg(d, s, n, r) dma_map_sg_attrs(d, s, n, r, 0)
408 #define dma_unmap_sg(d, s, n, r) dma_unmap_sg_attrs(d, s, n, r, 0)
409 #define dma_map_page(d, p, o, s, r) dma_map_page_attrs(d, p, o, s, r, 0)
410 #define dma_unmap_page(d, a, s, r) dma_unmap_page_attrs(d, a, s, r, 0)
411 #define dma_get_sgtable(d, t, v, h, s) dma_get_sgtable_attrs(d, t, v, h, s, 0)
412 #define dma_mmap_coherent(d, v, c, h, s) dma_mmap_attrs(d, v, c, h, s, 0)
413 
414 static inline void *dma_alloc_coherent(struct device *dev, size_t size,
415 		dma_addr_t *dma_handle, gfp_t gfp)
416 {
417 	return dma_alloc_attrs(dev, size, dma_handle, gfp,
418 			(gfp & __GFP_NOWARN) ? DMA_ATTR_NO_WARN : 0);
419 }
420 
421 static inline void dma_free_coherent(struct device *dev, size_t size,
422 		void *cpu_addr, dma_addr_t dma_handle)
423 {
424 	return dma_free_attrs(dev, size, cpu_addr, dma_handle, 0);
425 }
426 
427 
428 static inline u64 dma_get_mask(struct device *dev)
429 {
430 	if (dev->dma_mask && *dev->dma_mask)
431 		return *dev->dma_mask;
432 	return DMA_BIT_MASK(32);
433 }
434 
435 /*
436  * Set both the DMA mask and the coherent DMA mask to the same thing.
437  * Note that we don't check the return value from dma_set_coherent_mask()
438  * as the DMA API guarantees that the coherent DMA mask can be set to
439  * the same or smaller than the streaming DMA mask.
440  */
441 static inline int dma_set_mask_and_coherent(struct device *dev, u64 mask)
442 {
443 	int rc = dma_set_mask(dev, mask);
444 	if (rc == 0)
445 		dma_set_coherent_mask(dev, mask);
446 	return rc;
447 }
448 
449 /*
450  * Similar to the above, except it deals with the case where the device
451  * does not have dev->dma_mask appropriately setup.
452  */
453 static inline int dma_coerce_mask_and_coherent(struct device *dev, u64 mask)
454 {
455 	dev->dma_mask = &dev->coherent_dma_mask;
456 	return dma_set_mask_and_coherent(dev, mask);
457 }
458 
459 /**
460  * dma_addressing_limited - return if the device is addressing limited
461  * @dev:	device to check
462  *
463  * Return %true if the devices DMA mask is too small to address all memory in
464  * the system, else %false.  Lack of addressing bits is the prime reason for
465  * bounce buffering, but might not be the only one.
466  */
467 static inline bool dma_addressing_limited(struct device *dev)
468 {
469 	return min_not_zero(dma_get_mask(dev), dev->bus_dma_limit) <
470 			    dma_get_required_mask(dev);
471 }
472 
473 static inline unsigned int dma_get_max_seg_size(struct device *dev)
474 {
475 	if (dev->dma_parms && dev->dma_parms->max_segment_size)
476 		return dev->dma_parms->max_segment_size;
477 	return SZ_64K;
478 }
479 
480 static inline int dma_set_max_seg_size(struct device *dev, unsigned int size)
481 {
482 	if (dev->dma_parms) {
483 		dev->dma_parms->max_segment_size = size;
484 		return 0;
485 	}
486 	return -EIO;
487 }
488 
489 static inline unsigned long dma_get_seg_boundary(struct device *dev)
490 {
491 	if (dev->dma_parms && dev->dma_parms->segment_boundary_mask)
492 		return dev->dma_parms->segment_boundary_mask;
493 	return ULONG_MAX;
494 }
495 
496 /**
497  * dma_get_seg_boundary_nr_pages - return the segment boundary in "page" units
498  * @dev: device to guery the boundary for
499  * @page_shift: ilog() of the IOMMU page size
500  *
501  * Return the segment boundary in IOMMU page units (which may be different from
502  * the CPU page size) for the passed in device.
503  *
504  * If @dev is NULL a boundary of U32_MAX is assumed, this case is just for
505  * non-DMA API callers.
506  */
507 static inline unsigned long dma_get_seg_boundary_nr_pages(struct device *dev,
508 		unsigned int page_shift)
509 {
510 	if (!dev)
511 		return (U32_MAX >> page_shift) + 1;
512 	return (dma_get_seg_boundary(dev) >> page_shift) + 1;
513 }
514 
515 static inline int dma_set_seg_boundary(struct device *dev, unsigned long mask)
516 {
517 	if (dev->dma_parms) {
518 		dev->dma_parms->segment_boundary_mask = mask;
519 		return 0;
520 	}
521 	return -EIO;
522 }
523 
524 static inline unsigned int dma_get_min_align_mask(struct device *dev)
525 {
526 	if (dev->dma_parms)
527 		return dev->dma_parms->min_align_mask;
528 	return 0;
529 }
530 
531 static inline int dma_set_min_align_mask(struct device *dev,
532 		unsigned int min_align_mask)
533 {
534 	if (WARN_ON_ONCE(!dev->dma_parms))
535 		return -EIO;
536 	dev->dma_parms->min_align_mask = min_align_mask;
537 	return 0;
538 }
539 
540 static inline int dma_get_cache_alignment(void)
541 {
542 #ifdef ARCH_DMA_MINALIGN
543 	return ARCH_DMA_MINALIGN;
544 #endif
545 	return 1;
546 }
547 
548 static inline void *dmam_alloc_coherent(struct device *dev, size_t size,
549 		dma_addr_t *dma_handle, gfp_t gfp)
550 {
551 	return dmam_alloc_attrs(dev, size, dma_handle, gfp,
552 			(gfp & __GFP_NOWARN) ? DMA_ATTR_NO_WARN : 0);
553 }
554 
555 static inline void *dma_alloc_wc(struct device *dev, size_t size,
556 				 dma_addr_t *dma_addr, gfp_t gfp)
557 {
558 	unsigned long attrs = DMA_ATTR_WRITE_COMBINE;
559 
560 	if (gfp & __GFP_NOWARN)
561 		attrs |= DMA_ATTR_NO_WARN;
562 
563 	return dma_alloc_attrs(dev, size, dma_addr, gfp, attrs);
564 }
565 
566 static inline void dma_free_wc(struct device *dev, size_t size,
567 			       void *cpu_addr, dma_addr_t dma_addr)
568 {
569 	return dma_free_attrs(dev, size, cpu_addr, dma_addr,
570 			      DMA_ATTR_WRITE_COMBINE);
571 }
572 
573 static inline int dma_mmap_wc(struct device *dev,
574 			      struct vm_area_struct *vma,
575 			      void *cpu_addr, dma_addr_t dma_addr,
576 			      size_t size)
577 {
578 	return dma_mmap_attrs(dev, vma, cpu_addr, dma_addr, size,
579 			      DMA_ATTR_WRITE_COMBINE);
580 }
581 
582 #ifdef CONFIG_NEED_DMA_MAP_STATE
583 #define DEFINE_DMA_UNMAP_ADDR(ADDR_NAME)        dma_addr_t ADDR_NAME
584 #define DEFINE_DMA_UNMAP_LEN(LEN_NAME)          __u32 LEN_NAME
585 #define dma_unmap_addr(PTR, ADDR_NAME)           ((PTR)->ADDR_NAME)
586 #define dma_unmap_addr_set(PTR, ADDR_NAME, VAL)  (((PTR)->ADDR_NAME) = (VAL))
587 #define dma_unmap_len(PTR, LEN_NAME)             ((PTR)->LEN_NAME)
588 #define dma_unmap_len_set(PTR, LEN_NAME, VAL)    (((PTR)->LEN_NAME) = (VAL))
589 #else
590 #define DEFINE_DMA_UNMAP_ADDR(ADDR_NAME)
591 #define DEFINE_DMA_UNMAP_LEN(LEN_NAME)
592 #define dma_unmap_addr(PTR, ADDR_NAME)           (0)
593 #define dma_unmap_addr_set(PTR, ADDR_NAME, VAL)  do { } while (0)
594 #define dma_unmap_len(PTR, LEN_NAME)             (0)
595 #define dma_unmap_len_set(PTR, LEN_NAME, VAL)    do { } while (0)
596 #endif
597 
598 #endif /* _LINUX_DMA_MAPPING_H */
599