xref: /linux-6.15/include/linux/dma-mapping.h (revision b4f33f6d)
1 #ifndef _LINUX_DMA_MAPPING_H
2 #define _LINUX_DMA_MAPPING_H
3 
4 #include <linux/sizes.h>
5 #include <linux/string.h>
6 #include <linux/device.h>
7 #include <linux/err.h>
8 #include <linux/dma-debug.h>
9 #include <linux/dma-direction.h>
10 #include <linux/scatterlist.h>
11 #include <linux/kmemcheck.h>
12 #include <linux/bug.h>
13 
14 /**
15  * List of possible attributes associated with a DMA mapping. The semantics
16  * of each attribute should be defined in Documentation/DMA-attributes.txt.
17  *
18  * DMA_ATTR_WRITE_BARRIER: DMA to a memory region with this attribute
19  * forces all pending DMA writes to complete.
20  */
21 #define DMA_ATTR_WRITE_BARRIER		(1UL << 0)
22 /*
23  * DMA_ATTR_WEAK_ORDERING: Specifies that reads and writes to the mapping
24  * may be weakly ordered, that is that reads and writes may pass each other.
25  */
26 #define DMA_ATTR_WEAK_ORDERING		(1UL << 1)
27 /*
28  * DMA_ATTR_WRITE_COMBINE: Specifies that writes to the mapping may be
29  * buffered to improve performance.
30  */
31 #define DMA_ATTR_WRITE_COMBINE		(1UL << 2)
32 /*
33  * DMA_ATTR_NON_CONSISTENT: Lets the platform to choose to return either
34  * consistent or non-consistent memory as it sees fit.
35  */
36 #define DMA_ATTR_NON_CONSISTENT		(1UL << 3)
37 /*
38  * DMA_ATTR_NO_KERNEL_MAPPING: Lets the platform to avoid creating a kernel
39  * virtual mapping for the allocated buffer.
40  */
41 #define DMA_ATTR_NO_KERNEL_MAPPING	(1UL << 4)
42 /*
43  * DMA_ATTR_SKIP_CPU_SYNC: Allows platform code to skip synchronization of
44  * the CPU cache for the given buffer assuming that it has been already
45  * transferred to 'device' domain.
46  */
47 #define DMA_ATTR_SKIP_CPU_SYNC		(1UL << 5)
48 /*
49  * DMA_ATTR_FORCE_CONTIGUOUS: Forces contiguous allocation of the buffer
50  * in physical memory.
51  */
52 #define DMA_ATTR_FORCE_CONTIGUOUS	(1UL << 6)
53 /*
54  * DMA_ATTR_ALLOC_SINGLE_PAGES: This is a hint to the DMA-mapping subsystem
55  * that it's probably not worth the time to try to allocate memory to in a way
56  * that gives better TLB efficiency.
57  */
58 #define DMA_ATTR_ALLOC_SINGLE_PAGES	(1UL << 7)
59 
60 /*
61  * A dma_addr_t can hold any valid DMA or bus address for the platform.
62  * It can be given to a device to use as a DMA source or target.  A CPU cannot
63  * reference a dma_addr_t directly because there may be translation between
64  * its physical address space and the bus address space.
65  */
66 struct dma_map_ops {
67 	void* (*alloc)(struct device *dev, size_t size,
68 				dma_addr_t *dma_handle, gfp_t gfp,
69 				unsigned long attrs);
70 	void (*free)(struct device *dev, size_t size,
71 			      void *vaddr, dma_addr_t dma_handle,
72 			      unsigned long attrs);
73 	int (*mmap)(struct device *, struct vm_area_struct *,
74 			  void *, dma_addr_t, size_t,
75 			  unsigned long attrs);
76 
77 	int (*get_sgtable)(struct device *dev, struct sg_table *sgt, void *,
78 			   dma_addr_t, size_t, unsigned long attrs);
79 
80 	dma_addr_t (*map_page)(struct device *dev, struct page *page,
81 			       unsigned long offset, size_t size,
82 			       enum dma_data_direction dir,
83 			       unsigned long attrs);
84 	void (*unmap_page)(struct device *dev, dma_addr_t dma_handle,
85 			   size_t size, enum dma_data_direction dir,
86 			   unsigned long attrs);
87 	/*
88 	 * map_sg returns 0 on error and a value > 0 on success.
89 	 * It should never return a value < 0.
90 	 */
91 	int (*map_sg)(struct device *dev, struct scatterlist *sg,
92 		      int nents, enum dma_data_direction dir,
93 		      unsigned long attrs);
94 	void (*unmap_sg)(struct device *dev,
95 			 struct scatterlist *sg, int nents,
96 			 enum dma_data_direction dir,
97 			 unsigned long attrs);
98 	dma_addr_t (*map_resource)(struct device *dev, phys_addr_t phys_addr,
99 			       size_t size, enum dma_data_direction dir,
100 			       unsigned long attrs);
101 	void (*unmap_resource)(struct device *dev, dma_addr_t dma_handle,
102 			   size_t size, enum dma_data_direction dir,
103 			   unsigned long attrs);
104 	void (*sync_single_for_cpu)(struct device *dev,
105 				    dma_addr_t dma_handle, size_t size,
106 				    enum dma_data_direction dir);
107 	void (*sync_single_for_device)(struct device *dev,
108 				       dma_addr_t dma_handle, size_t size,
109 				       enum dma_data_direction dir);
110 	void (*sync_sg_for_cpu)(struct device *dev,
111 				struct scatterlist *sg, int nents,
112 				enum dma_data_direction dir);
113 	void (*sync_sg_for_device)(struct device *dev,
114 				   struct scatterlist *sg, int nents,
115 				   enum dma_data_direction dir);
116 	int (*mapping_error)(struct device *dev, dma_addr_t dma_addr);
117 	int (*dma_supported)(struct device *dev, u64 mask);
118 	int (*set_dma_mask)(struct device *dev, u64 mask);
119 #ifdef ARCH_HAS_DMA_GET_REQUIRED_MASK
120 	u64 (*get_required_mask)(struct device *dev);
121 #endif
122 	int is_phys;
123 };
124 
125 extern struct dma_map_ops dma_noop_ops;
126 
127 #define DMA_BIT_MASK(n)	(((n) == 64) ? ~0ULL : ((1ULL<<(n))-1))
128 
129 #define DMA_MASK_NONE	0x0ULL
130 
131 static inline int valid_dma_direction(int dma_direction)
132 {
133 	return ((dma_direction == DMA_BIDIRECTIONAL) ||
134 		(dma_direction == DMA_TO_DEVICE) ||
135 		(dma_direction == DMA_FROM_DEVICE));
136 }
137 
138 static inline int is_device_dma_capable(struct device *dev)
139 {
140 	return dev->dma_mask != NULL && *dev->dma_mask != DMA_MASK_NONE;
141 }
142 
143 #ifdef CONFIG_HAVE_GENERIC_DMA_COHERENT
144 /*
145  * These three functions are only for dma allocator.
146  * Don't use them in device drivers.
147  */
148 int dma_alloc_from_coherent(struct device *dev, ssize_t size,
149 				       dma_addr_t *dma_handle, void **ret);
150 int dma_release_from_coherent(struct device *dev, int order, void *vaddr);
151 
152 int dma_mmap_from_coherent(struct device *dev, struct vm_area_struct *vma,
153 			    void *cpu_addr, size_t size, int *ret);
154 #else
155 #define dma_alloc_from_coherent(dev, size, handle, ret) (0)
156 #define dma_release_from_coherent(dev, order, vaddr) (0)
157 #define dma_mmap_from_coherent(dev, vma, vaddr, order, ret) (0)
158 #endif /* CONFIG_HAVE_GENERIC_DMA_COHERENT */
159 
160 #ifdef CONFIG_HAS_DMA
161 #include <asm/dma-mapping.h>
162 #else
163 /*
164  * Define the dma api to allow compilation but not linking of
165  * dma dependent code.  Code that depends on the dma-mapping
166  * API needs to set 'depends on HAS_DMA' in its Kconfig
167  */
168 extern struct dma_map_ops bad_dma_ops;
169 static inline struct dma_map_ops *get_dma_ops(struct device *dev)
170 {
171 	return &bad_dma_ops;
172 }
173 #endif
174 
175 static inline dma_addr_t dma_map_single_attrs(struct device *dev, void *ptr,
176 					      size_t size,
177 					      enum dma_data_direction dir,
178 					      unsigned long attrs)
179 {
180 	struct dma_map_ops *ops = get_dma_ops(dev);
181 	dma_addr_t addr;
182 
183 	kmemcheck_mark_initialized(ptr, size);
184 	BUG_ON(!valid_dma_direction(dir));
185 	addr = ops->map_page(dev, virt_to_page(ptr),
186 			     offset_in_page(ptr), size,
187 			     dir, attrs);
188 	debug_dma_map_page(dev, virt_to_page(ptr),
189 			   offset_in_page(ptr), size,
190 			   dir, addr, true);
191 	return addr;
192 }
193 
194 static inline void dma_unmap_single_attrs(struct device *dev, dma_addr_t addr,
195 					  size_t size,
196 					  enum dma_data_direction dir,
197 					  unsigned long attrs)
198 {
199 	struct dma_map_ops *ops = get_dma_ops(dev);
200 
201 	BUG_ON(!valid_dma_direction(dir));
202 	if (ops->unmap_page)
203 		ops->unmap_page(dev, addr, size, dir, attrs);
204 	debug_dma_unmap_page(dev, addr, size, dir, true);
205 }
206 
207 /*
208  * dma_maps_sg_attrs returns 0 on error and > 0 on success.
209  * It should never return a value < 0.
210  */
211 static inline int dma_map_sg_attrs(struct device *dev, struct scatterlist *sg,
212 				   int nents, enum dma_data_direction dir,
213 				   unsigned long attrs)
214 {
215 	struct dma_map_ops *ops = get_dma_ops(dev);
216 	int i, ents;
217 	struct scatterlist *s;
218 
219 	for_each_sg(sg, s, nents, i)
220 		kmemcheck_mark_initialized(sg_virt(s), s->length);
221 	BUG_ON(!valid_dma_direction(dir));
222 	ents = ops->map_sg(dev, sg, nents, dir, attrs);
223 	BUG_ON(ents < 0);
224 	debug_dma_map_sg(dev, sg, nents, ents, dir);
225 
226 	return ents;
227 }
228 
229 static inline void dma_unmap_sg_attrs(struct device *dev, struct scatterlist *sg,
230 				      int nents, enum dma_data_direction dir,
231 				      unsigned long attrs)
232 {
233 	struct dma_map_ops *ops = get_dma_ops(dev);
234 
235 	BUG_ON(!valid_dma_direction(dir));
236 	debug_dma_unmap_sg(dev, sg, nents, dir);
237 	if (ops->unmap_sg)
238 		ops->unmap_sg(dev, sg, nents, dir, attrs);
239 }
240 
241 static inline dma_addr_t dma_map_page(struct device *dev, struct page *page,
242 				      size_t offset, size_t size,
243 				      enum dma_data_direction dir)
244 {
245 	struct dma_map_ops *ops = get_dma_ops(dev);
246 	dma_addr_t addr;
247 
248 	kmemcheck_mark_initialized(page_address(page) + offset, size);
249 	BUG_ON(!valid_dma_direction(dir));
250 	addr = ops->map_page(dev, page, offset, size, dir, 0);
251 	debug_dma_map_page(dev, page, offset, size, dir, addr, false);
252 
253 	return addr;
254 }
255 
256 static inline void dma_unmap_page(struct device *dev, dma_addr_t addr,
257 				  size_t size, enum dma_data_direction dir)
258 {
259 	struct dma_map_ops *ops = get_dma_ops(dev);
260 
261 	BUG_ON(!valid_dma_direction(dir));
262 	if (ops->unmap_page)
263 		ops->unmap_page(dev, addr, size, dir, 0);
264 	debug_dma_unmap_page(dev, addr, size, dir, false);
265 }
266 
267 static inline dma_addr_t dma_map_resource(struct device *dev,
268 					  phys_addr_t phys_addr,
269 					  size_t size,
270 					  enum dma_data_direction dir,
271 					  unsigned long attrs)
272 {
273 	struct dma_map_ops *ops = get_dma_ops(dev);
274 	dma_addr_t addr;
275 
276 	BUG_ON(!valid_dma_direction(dir));
277 
278 	/* Don't allow RAM to be mapped */
279 	BUG_ON(pfn_valid(PHYS_PFN(phys_addr)));
280 
281 	addr = phys_addr;
282 	if (ops->map_resource)
283 		addr = ops->map_resource(dev, phys_addr, size, dir, attrs);
284 
285 	debug_dma_map_resource(dev, phys_addr, size, dir, addr);
286 
287 	return addr;
288 }
289 
290 static inline void dma_unmap_resource(struct device *dev, dma_addr_t addr,
291 				      size_t size, enum dma_data_direction dir,
292 				      unsigned long attrs)
293 {
294 	struct dma_map_ops *ops = get_dma_ops(dev);
295 
296 	BUG_ON(!valid_dma_direction(dir));
297 	if (ops->unmap_resource)
298 		ops->unmap_resource(dev, addr, size, dir, attrs);
299 	debug_dma_unmap_resource(dev, addr, size, dir);
300 }
301 
302 static inline void dma_sync_single_for_cpu(struct device *dev, dma_addr_t addr,
303 					   size_t size,
304 					   enum dma_data_direction dir)
305 {
306 	struct dma_map_ops *ops = get_dma_ops(dev);
307 
308 	BUG_ON(!valid_dma_direction(dir));
309 	if (ops->sync_single_for_cpu)
310 		ops->sync_single_for_cpu(dev, addr, size, dir);
311 	debug_dma_sync_single_for_cpu(dev, addr, size, dir);
312 }
313 
314 static inline void dma_sync_single_for_device(struct device *dev,
315 					      dma_addr_t addr, size_t size,
316 					      enum dma_data_direction dir)
317 {
318 	struct dma_map_ops *ops = get_dma_ops(dev);
319 
320 	BUG_ON(!valid_dma_direction(dir));
321 	if (ops->sync_single_for_device)
322 		ops->sync_single_for_device(dev, addr, size, dir);
323 	debug_dma_sync_single_for_device(dev, addr, size, dir);
324 }
325 
326 static inline void dma_sync_single_range_for_cpu(struct device *dev,
327 						 dma_addr_t addr,
328 						 unsigned long offset,
329 						 size_t size,
330 						 enum dma_data_direction dir)
331 {
332 	const struct dma_map_ops *ops = get_dma_ops(dev);
333 
334 	BUG_ON(!valid_dma_direction(dir));
335 	if (ops->sync_single_for_cpu)
336 		ops->sync_single_for_cpu(dev, addr + offset, size, dir);
337 	debug_dma_sync_single_range_for_cpu(dev, addr, offset, size, dir);
338 }
339 
340 static inline void dma_sync_single_range_for_device(struct device *dev,
341 						    dma_addr_t addr,
342 						    unsigned long offset,
343 						    size_t size,
344 						    enum dma_data_direction dir)
345 {
346 	const struct dma_map_ops *ops = get_dma_ops(dev);
347 
348 	BUG_ON(!valid_dma_direction(dir));
349 	if (ops->sync_single_for_device)
350 		ops->sync_single_for_device(dev, addr + offset, size, dir);
351 	debug_dma_sync_single_range_for_device(dev, addr, offset, size, dir);
352 }
353 
354 static inline void
355 dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg,
356 		    int nelems, enum dma_data_direction dir)
357 {
358 	struct dma_map_ops *ops = get_dma_ops(dev);
359 
360 	BUG_ON(!valid_dma_direction(dir));
361 	if (ops->sync_sg_for_cpu)
362 		ops->sync_sg_for_cpu(dev, sg, nelems, dir);
363 	debug_dma_sync_sg_for_cpu(dev, sg, nelems, dir);
364 }
365 
366 static inline void
367 dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg,
368 		       int nelems, enum dma_data_direction dir)
369 {
370 	struct dma_map_ops *ops = get_dma_ops(dev);
371 
372 	BUG_ON(!valid_dma_direction(dir));
373 	if (ops->sync_sg_for_device)
374 		ops->sync_sg_for_device(dev, sg, nelems, dir);
375 	debug_dma_sync_sg_for_device(dev, sg, nelems, dir);
376 
377 }
378 
379 #define dma_map_single(d, a, s, r) dma_map_single_attrs(d, a, s, r, 0)
380 #define dma_unmap_single(d, a, s, r) dma_unmap_single_attrs(d, a, s, r, 0)
381 #define dma_map_sg(d, s, n, r) dma_map_sg_attrs(d, s, n, r, 0)
382 #define dma_unmap_sg(d, s, n, r) dma_unmap_sg_attrs(d, s, n, r, 0)
383 
384 extern int dma_common_mmap(struct device *dev, struct vm_area_struct *vma,
385 			   void *cpu_addr, dma_addr_t dma_addr, size_t size);
386 
387 void *dma_common_contiguous_remap(struct page *page, size_t size,
388 			unsigned long vm_flags,
389 			pgprot_t prot, const void *caller);
390 
391 void *dma_common_pages_remap(struct page **pages, size_t size,
392 			unsigned long vm_flags, pgprot_t prot,
393 			const void *caller);
394 void dma_common_free_remap(void *cpu_addr, size_t size, unsigned long vm_flags);
395 
396 /**
397  * dma_mmap_attrs - map a coherent DMA allocation into user space
398  * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
399  * @vma: vm_area_struct describing requested user mapping
400  * @cpu_addr: kernel CPU-view address returned from dma_alloc_attrs
401  * @handle: device-view address returned from dma_alloc_attrs
402  * @size: size of memory originally requested in dma_alloc_attrs
403  * @attrs: attributes of mapping properties requested in dma_alloc_attrs
404  *
405  * Map a coherent DMA buffer previously allocated by dma_alloc_attrs
406  * into user space.  The coherent DMA buffer must not be freed by the
407  * driver until the user space mapping has been released.
408  */
409 static inline int
410 dma_mmap_attrs(struct device *dev, struct vm_area_struct *vma, void *cpu_addr,
411 	       dma_addr_t dma_addr, size_t size, unsigned long attrs)
412 {
413 	struct dma_map_ops *ops = get_dma_ops(dev);
414 	BUG_ON(!ops);
415 	if (ops->mmap)
416 		return ops->mmap(dev, vma, cpu_addr, dma_addr, size, attrs);
417 	return dma_common_mmap(dev, vma, cpu_addr, dma_addr, size);
418 }
419 
420 #define dma_mmap_coherent(d, v, c, h, s) dma_mmap_attrs(d, v, c, h, s, 0)
421 
422 int
423 dma_common_get_sgtable(struct device *dev, struct sg_table *sgt,
424 		       void *cpu_addr, dma_addr_t dma_addr, size_t size);
425 
426 static inline int
427 dma_get_sgtable_attrs(struct device *dev, struct sg_table *sgt, void *cpu_addr,
428 		      dma_addr_t dma_addr, size_t size,
429 		      unsigned long attrs)
430 {
431 	struct dma_map_ops *ops = get_dma_ops(dev);
432 	BUG_ON(!ops);
433 	if (ops->get_sgtable)
434 		return ops->get_sgtable(dev, sgt, cpu_addr, dma_addr, size,
435 					attrs);
436 	return dma_common_get_sgtable(dev, sgt, cpu_addr, dma_addr, size);
437 }
438 
439 #define dma_get_sgtable(d, t, v, h, s) dma_get_sgtable_attrs(d, t, v, h, s, 0)
440 
441 #ifndef arch_dma_alloc_attrs
442 #define arch_dma_alloc_attrs(dev, flag)	(true)
443 #endif
444 
445 static inline void *dma_alloc_attrs(struct device *dev, size_t size,
446 				       dma_addr_t *dma_handle, gfp_t flag,
447 				       unsigned long attrs)
448 {
449 	struct dma_map_ops *ops = get_dma_ops(dev);
450 	void *cpu_addr;
451 
452 	BUG_ON(!ops);
453 
454 	if (dma_alloc_from_coherent(dev, size, dma_handle, &cpu_addr))
455 		return cpu_addr;
456 
457 	if (!arch_dma_alloc_attrs(&dev, &flag))
458 		return NULL;
459 	if (!ops->alloc)
460 		return NULL;
461 
462 	cpu_addr = ops->alloc(dev, size, dma_handle, flag, attrs);
463 	debug_dma_alloc_coherent(dev, size, *dma_handle, cpu_addr);
464 	return cpu_addr;
465 }
466 
467 static inline void dma_free_attrs(struct device *dev, size_t size,
468 				     void *cpu_addr, dma_addr_t dma_handle,
469 				     unsigned long attrs)
470 {
471 	struct dma_map_ops *ops = get_dma_ops(dev);
472 
473 	BUG_ON(!ops);
474 	WARN_ON(irqs_disabled());
475 
476 	if (dma_release_from_coherent(dev, get_order(size), cpu_addr))
477 		return;
478 
479 	if (!ops->free || !cpu_addr)
480 		return;
481 
482 	debug_dma_free_coherent(dev, size, cpu_addr, dma_handle);
483 	ops->free(dev, size, cpu_addr, dma_handle, attrs);
484 }
485 
486 static inline void *dma_alloc_coherent(struct device *dev, size_t size,
487 		dma_addr_t *dma_handle, gfp_t flag)
488 {
489 	return dma_alloc_attrs(dev, size, dma_handle, flag, 0);
490 }
491 
492 static inline void dma_free_coherent(struct device *dev, size_t size,
493 		void *cpu_addr, dma_addr_t dma_handle)
494 {
495 	return dma_free_attrs(dev, size, cpu_addr, dma_handle, 0);
496 }
497 
498 static inline void *dma_alloc_noncoherent(struct device *dev, size_t size,
499 		dma_addr_t *dma_handle, gfp_t gfp)
500 {
501 	return dma_alloc_attrs(dev, size, dma_handle, gfp,
502 			       DMA_ATTR_NON_CONSISTENT);
503 }
504 
505 static inline void dma_free_noncoherent(struct device *dev, size_t size,
506 		void *cpu_addr, dma_addr_t dma_handle)
507 {
508 	dma_free_attrs(dev, size, cpu_addr, dma_handle,
509 		       DMA_ATTR_NON_CONSISTENT);
510 }
511 
512 static inline int dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
513 {
514 	debug_dma_mapping_error(dev, dma_addr);
515 
516 	if (get_dma_ops(dev)->mapping_error)
517 		return get_dma_ops(dev)->mapping_error(dev, dma_addr);
518 
519 #ifdef DMA_ERROR_CODE
520 	return dma_addr == DMA_ERROR_CODE;
521 #else
522 	return 0;
523 #endif
524 }
525 
526 #ifndef HAVE_ARCH_DMA_SUPPORTED
527 static inline int dma_supported(struct device *dev, u64 mask)
528 {
529 	struct dma_map_ops *ops = get_dma_ops(dev);
530 
531 	if (!ops)
532 		return 0;
533 	if (!ops->dma_supported)
534 		return 1;
535 	return ops->dma_supported(dev, mask);
536 }
537 #endif
538 
539 #ifndef HAVE_ARCH_DMA_SET_MASK
540 static inline int dma_set_mask(struct device *dev, u64 mask)
541 {
542 	struct dma_map_ops *ops = get_dma_ops(dev);
543 
544 	if (ops->set_dma_mask)
545 		return ops->set_dma_mask(dev, mask);
546 
547 	if (!dev->dma_mask || !dma_supported(dev, mask))
548 		return -EIO;
549 	*dev->dma_mask = mask;
550 	return 0;
551 }
552 #endif
553 
554 static inline u64 dma_get_mask(struct device *dev)
555 {
556 	if (dev && dev->dma_mask && *dev->dma_mask)
557 		return *dev->dma_mask;
558 	return DMA_BIT_MASK(32);
559 }
560 
561 #ifdef CONFIG_ARCH_HAS_DMA_SET_COHERENT_MASK
562 int dma_set_coherent_mask(struct device *dev, u64 mask);
563 #else
564 static inline int dma_set_coherent_mask(struct device *dev, u64 mask)
565 {
566 	if (!dma_supported(dev, mask))
567 		return -EIO;
568 	dev->coherent_dma_mask = mask;
569 	return 0;
570 }
571 #endif
572 
573 /*
574  * Set both the DMA mask and the coherent DMA mask to the same thing.
575  * Note that we don't check the return value from dma_set_coherent_mask()
576  * as the DMA API guarantees that the coherent DMA mask can be set to
577  * the same or smaller than the streaming DMA mask.
578  */
579 static inline int dma_set_mask_and_coherent(struct device *dev, u64 mask)
580 {
581 	int rc = dma_set_mask(dev, mask);
582 	if (rc == 0)
583 		dma_set_coherent_mask(dev, mask);
584 	return rc;
585 }
586 
587 /*
588  * Similar to the above, except it deals with the case where the device
589  * does not have dev->dma_mask appropriately setup.
590  */
591 static inline int dma_coerce_mask_and_coherent(struct device *dev, u64 mask)
592 {
593 	dev->dma_mask = &dev->coherent_dma_mask;
594 	return dma_set_mask_and_coherent(dev, mask);
595 }
596 
597 extern u64 dma_get_required_mask(struct device *dev);
598 
599 #ifndef arch_setup_dma_ops
600 static inline void arch_setup_dma_ops(struct device *dev, u64 dma_base,
601 				      u64 size, const struct iommu_ops *iommu,
602 				      bool coherent) { }
603 #endif
604 
605 #ifndef arch_teardown_dma_ops
606 static inline void arch_teardown_dma_ops(struct device *dev) { }
607 #endif
608 
609 static inline unsigned int dma_get_max_seg_size(struct device *dev)
610 {
611 	if (dev->dma_parms && dev->dma_parms->max_segment_size)
612 		return dev->dma_parms->max_segment_size;
613 	return SZ_64K;
614 }
615 
616 static inline unsigned int dma_set_max_seg_size(struct device *dev,
617 						unsigned int size)
618 {
619 	if (dev->dma_parms) {
620 		dev->dma_parms->max_segment_size = size;
621 		return 0;
622 	}
623 	return -EIO;
624 }
625 
626 static inline unsigned long dma_get_seg_boundary(struct device *dev)
627 {
628 	if (dev->dma_parms && dev->dma_parms->segment_boundary_mask)
629 		return dev->dma_parms->segment_boundary_mask;
630 	return DMA_BIT_MASK(32);
631 }
632 
633 static inline int dma_set_seg_boundary(struct device *dev, unsigned long mask)
634 {
635 	if (dev->dma_parms) {
636 		dev->dma_parms->segment_boundary_mask = mask;
637 		return 0;
638 	}
639 	return -EIO;
640 }
641 
642 #ifndef dma_max_pfn
643 static inline unsigned long dma_max_pfn(struct device *dev)
644 {
645 	return *dev->dma_mask >> PAGE_SHIFT;
646 }
647 #endif
648 
649 static inline void *dma_zalloc_coherent(struct device *dev, size_t size,
650 					dma_addr_t *dma_handle, gfp_t flag)
651 {
652 	void *ret = dma_alloc_coherent(dev, size, dma_handle,
653 				       flag | __GFP_ZERO);
654 	return ret;
655 }
656 
657 #ifdef CONFIG_HAS_DMA
658 static inline int dma_get_cache_alignment(void)
659 {
660 #ifdef ARCH_DMA_MINALIGN
661 	return ARCH_DMA_MINALIGN;
662 #endif
663 	return 1;
664 }
665 #endif
666 
667 /* flags for the coherent memory api */
668 #define	DMA_MEMORY_MAP			0x01
669 #define DMA_MEMORY_IO			0x02
670 #define DMA_MEMORY_INCLUDES_CHILDREN	0x04
671 #define DMA_MEMORY_EXCLUSIVE		0x08
672 
673 #ifdef CONFIG_HAVE_GENERIC_DMA_COHERENT
674 int dma_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr,
675 				dma_addr_t device_addr, size_t size, int flags);
676 void dma_release_declared_memory(struct device *dev);
677 void *dma_mark_declared_memory_occupied(struct device *dev,
678 					dma_addr_t device_addr, size_t size);
679 #else
680 static inline int
681 dma_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr,
682 			    dma_addr_t device_addr, size_t size, int flags)
683 {
684 	return 0;
685 }
686 
687 static inline void
688 dma_release_declared_memory(struct device *dev)
689 {
690 }
691 
692 static inline void *
693 dma_mark_declared_memory_occupied(struct device *dev,
694 				  dma_addr_t device_addr, size_t size)
695 {
696 	return ERR_PTR(-EBUSY);
697 }
698 #endif /* CONFIG_HAVE_GENERIC_DMA_COHERENT */
699 
700 /*
701  * Managed DMA API
702  */
703 extern void *dmam_alloc_coherent(struct device *dev, size_t size,
704 				 dma_addr_t *dma_handle, gfp_t gfp);
705 extern void dmam_free_coherent(struct device *dev, size_t size, void *vaddr,
706 			       dma_addr_t dma_handle);
707 extern void *dmam_alloc_noncoherent(struct device *dev, size_t size,
708 				    dma_addr_t *dma_handle, gfp_t gfp);
709 extern void dmam_free_noncoherent(struct device *dev, size_t size, void *vaddr,
710 				  dma_addr_t dma_handle);
711 #ifdef CONFIG_HAVE_GENERIC_DMA_COHERENT
712 extern int dmam_declare_coherent_memory(struct device *dev,
713 					phys_addr_t phys_addr,
714 					dma_addr_t device_addr, size_t size,
715 					int flags);
716 extern void dmam_release_declared_memory(struct device *dev);
717 #else /* CONFIG_HAVE_GENERIC_DMA_COHERENT */
718 static inline int dmam_declare_coherent_memory(struct device *dev,
719 				phys_addr_t phys_addr, dma_addr_t device_addr,
720 				size_t size, gfp_t gfp)
721 {
722 	return 0;
723 }
724 
725 static inline void dmam_release_declared_memory(struct device *dev)
726 {
727 }
728 #endif /* CONFIG_HAVE_GENERIC_DMA_COHERENT */
729 
730 static inline void *dma_alloc_wc(struct device *dev, size_t size,
731 				 dma_addr_t *dma_addr, gfp_t gfp)
732 {
733 	return dma_alloc_attrs(dev, size, dma_addr, gfp,
734 			       DMA_ATTR_WRITE_COMBINE);
735 }
736 #ifndef dma_alloc_writecombine
737 #define dma_alloc_writecombine dma_alloc_wc
738 #endif
739 
740 static inline void dma_free_wc(struct device *dev, size_t size,
741 			       void *cpu_addr, dma_addr_t dma_addr)
742 {
743 	return dma_free_attrs(dev, size, cpu_addr, dma_addr,
744 			      DMA_ATTR_WRITE_COMBINE);
745 }
746 #ifndef dma_free_writecombine
747 #define dma_free_writecombine dma_free_wc
748 #endif
749 
750 static inline int dma_mmap_wc(struct device *dev,
751 			      struct vm_area_struct *vma,
752 			      void *cpu_addr, dma_addr_t dma_addr,
753 			      size_t size)
754 {
755 	return dma_mmap_attrs(dev, vma, cpu_addr, dma_addr, size,
756 			      DMA_ATTR_WRITE_COMBINE);
757 }
758 #ifndef dma_mmap_writecombine
759 #define dma_mmap_writecombine dma_mmap_wc
760 #endif
761 
762 #if defined(CONFIG_NEED_DMA_MAP_STATE) || defined(CONFIG_DMA_API_DEBUG)
763 #define DEFINE_DMA_UNMAP_ADDR(ADDR_NAME)        dma_addr_t ADDR_NAME
764 #define DEFINE_DMA_UNMAP_LEN(LEN_NAME)          __u32 LEN_NAME
765 #define dma_unmap_addr(PTR, ADDR_NAME)           ((PTR)->ADDR_NAME)
766 #define dma_unmap_addr_set(PTR, ADDR_NAME, VAL)  (((PTR)->ADDR_NAME) = (VAL))
767 #define dma_unmap_len(PTR, LEN_NAME)             ((PTR)->LEN_NAME)
768 #define dma_unmap_len_set(PTR, LEN_NAME, VAL)    (((PTR)->LEN_NAME) = (VAL))
769 #else
770 #define DEFINE_DMA_UNMAP_ADDR(ADDR_NAME)
771 #define DEFINE_DMA_UNMAP_LEN(LEN_NAME)
772 #define dma_unmap_addr(PTR, ADDR_NAME)           (0)
773 #define dma_unmap_addr_set(PTR, ADDR_NAME, VAL)  do { } while (0)
774 #define dma_unmap_len(PTR, LEN_NAME)             (0)
775 #define dma_unmap_len_set(PTR, LEN_NAME, VAL)    do { } while (0)
776 #endif
777 
778 #endif
779