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
debug_dma_mapping_error(struct device * dev,dma_addr_t dma_addr)83 static inline void debug_dma_mapping_error(struct device *dev,
84 		dma_addr_t dma_addr)
85 {
86 }
debug_dma_map_single(struct device * dev,const void * addr,unsigned long len)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
dma_mapping_error(struct device * dev,dma_addr_t dma_addr)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 (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 dma_addr_t dma_map_resource(struct device *dev, phys_addr_t phys_addr,
114 		size_t size, enum dma_data_direction dir, unsigned long attrs);
115 void dma_unmap_resource(struct device *dev, dma_addr_t addr, size_t size,
116 		enum dma_data_direction dir, unsigned long attrs);
117 void dma_sync_single_for_cpu(struct device *dev, dma_addr_t addr, size_t size,
118 		enum dma_data_direction dir);
119 void dma_sync_single_for_device(struct device *dev, dma_addr_t addr,
120 		size_t size, enum dma_data_direction dir);
121 void dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg,
122 		    int nelems, enum dma_data_direction dir);
123 void dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg,
124 		       int nelems, enum dma_data_direction dir);
125 void *dma_alloc_attrs(struct device *dev, size_t size, dma_addr_t *dma_handle,
126 		gfp_t flag, unsigned long attrs);
127 void dma_free_attrs(struct device *dev, size_t size, void *cpu_addr,
128 		dma_addr_t dma_handle, unsigned long attrs);
129 void *dmam_alloc_attrs(struct device *dev, size_t size, dma_addr_t *dma_handle,
130 		gfp_t gfp, unsigned long attrs);
131 void dmam_free_coherent(struct device *dev, size_t size, void *vaddr,
132 		dma_addr_t dma_handle);
133 int dma_get_sgtable_attrs(struct device *dev, struct sg_table *sgt,
134 		void *cpu_addr, dma_addr_t dma_addr, size_t size,
135 		unsigned long attrs);
136 int dma_mmap_attrs(struct device *dev, struct vm_area_struct *vma,
137 		void *cpu_addr, dma_addr_t dma_addr, size_t size,
138 		unsigned long attrs);
139 bool dma_can_mmap(struct device *dev);
140 int dma_supported(struct device *dev, u64 mask);
141 int dma_set_mask(struct device *dev, u64 mask);
142 int dma_set_coherent_mask(struct device *dev, u64 mask);
143 u64 dma_get_required_mask(struct device *dev);
144 size_t dma_max_mapping_size(struct device *dev);
145 bool dma_need_sync(struct device *dev, dma_addr_t dma_addr);
146 unsigned long dma_get_merge_boundary(struct device *dev);
147 #else /* CONFIG_HAS_DMA */
dma_map_page_attrs(struct device * dev,struct page * page,size_t offset,size_t size,enum dma_data_direction dir,unsigned long attrs)148 static inline dma_addr_t dma_map_page_attrs(struct device *dev,
149 		struct page *page, size_t offset, size_t size,
150 		enum dma_data_direction dir, unsigned long attrs)
151 {
152 	return DMA_MAPPING_ERROR;
153 }
dma_unmap_page_attrs(struct device * dev,dma_addr_t addr,size_t size,enum dma_data_direction dir,unsigned long attrs)154 static inline void dma_unmap_page_attrs(struct device *dev, dma_addr_t addr,
155 		size_t size, enum dma_data_direction dir, unsigned long attrs)
156 {
157 }
dma_map_sg_attrs(struct device * dev,struct scatterlist * sg,int nents,enum dma_data_direction dir,unsigned long attrs)158 static inline int dma_map_sg_attrs(struct device *dev, struct scatterlist *sg,
159 		int nents, enum dma_data_direction dir, unsigned long attrs)
160 {
161 	return 0;
162 }
dma_unmap_sg_attrs(struct device * dev,struct scatterlist * sg,int nents,enum dma_data_direction dir,unsigned long attrs)163 static inline void dma_unmap_sg_attrs(struct device *dev,
164 		struct scatterlist *sg, int nents, enum dma_data_direction dir,
165 		unsigned long attrs)
166 {
167 }
dma_map_resource(struct device * dev,phys_addr_t phys_addr,size_t size,enum dma_data_direction dir,unsigned long attrs)168 static inline dma_addr_t dma_map_resource(struct device *dev,
169 		phys_addr_t phys_addr, size_t size, enum dma_data_direction dir,
170 		unsigned long attrs)
171 {
172 	return DMA_MAPPING_ERROR;
173 }
dma_unmap_resource(struct device * dev,dma_addr_t addr,size_t size,enum dma_data_direction dir,unsigned long attrs)174 static inline void dma_unmap_resource(struct device *dev, dma_addr_t addr,
175 		size_t size, enum dma_data_direction dir, unsigned long attrs)
176 {
177 }
dma_sync_single_for_cpu(struct device * dev,dma_addr_t addr,size_t size,enum dma_data_direction dir)178 static inline void dma_sync_single_for_cpu(struct device *dev, dma_addr_t addr,
179 		size_t size, enum dma_data_direction dir)
180 {
181 }
dma_sync_single_for_device(struct device * dev,dma_addr_t addr,size_t size,enum dma_data_direction dir)182 static inline void dma_sync_single_for_device(struct device *dev,
183 		dma_addr_t addr, size_t size, enum dma_data_direction dir)
184 {
185 }
dma_sync_sg_for_cpu(struct device * dev,struct scatterlist * sg,int nelems,enum dma_data_direction dir)186 static inline void dma_sync_sg_for_cpu(struct device *dev,
187 		struct scatterlist *sg, int nelems, enum dma_data_direction dir)
188 {
189 }
dma_sync_sg_for_device(struct device * dev,struct scatterlist * sg,int nelems,enum dma_data_direction dir)190 static inline void dma_sync_sg_for_device(struct device *dev,
191 		struct scatterlist *sg, int nelems, enum dma_data_direction dir)
192 {
193 }
dma_mapping_error(struct device * dev,dma_addr_t dma_addr)194 static inline int dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
195 {
196 	return -ENOMEM;
197 }
dma_alloc_attrs(struct device * dev,size_t size,dma_addr_t * dma_handle,gfp_t flag,unsigned long attrs)198 static inline void *dma_alloc_attrs(struct device *dev, size_t size,
199 		dma_addr_t *dma_handle, gfp_t flag, unsigned long attrs)
200 {
201 	return NULL;
202 }
dma_free_attrs(struct device * dev,size_t size,void * cpu_addr,dma_addr_t dma_handle,unsigned long attrs)203 static void dma_free_attrs(struct device *dev, size_t size, void *cpu_addr,
204 		dma_addr_t dma_handle, unsigned long attrs)
205 {
206 }
dmam_alloc_attrs(struct device * dev,size_t size,dma_addr_t * dma_handle,gfp_t gfp,unsigned long attrs)207 static inline void *dmam_alloc_attrs(struct device *dev, size_t size,
208 		dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
209 {
210 	return NULL;
211 }
dmam_free_coherent(struct device * dev,size_t size,void * vaddr,dma_addr_t dma_handle)212 static inline void dmam_free_coherent(struct device *dev, size_t size,
213 		void *vaddr, dma_addr_t dma_handle)
214 {
215 }
dma_get_sgtable_attrs(struct device * dev,struct sg_table * sgt,void * cpu_addr,dma_addr_t dma_addr,size_t size,unsigned long attrs)216 static inline int dma_get_sgtable_attrs(struct device *dev,
217 		struct sg_table *sgt, void *cpu_addr, dma_addr_t dma_addr,
218 		size_t size, unsigned long attrs)
219 {
220 	return -ENXIO;
221 }
dma_mmap_attrs(struct device * dev,struct vm_area_struct * vma,void * cpu_addr,dma_addr_t dma_addr,size_t size,unsigned long attrs)222 static inline int dma_mmap_attrs(struct device *dev, struct vm_area_struct *vma,
223 		void *cpu_addr, dma_addr_t dma_addr, size_t size,
224 		unsigned long attrs)
225 {
226 	return -ENXIO;
227 }
dma_can_mmap(struct device * dev)228 static inline bool dma_can_mmap(struct device *dev)
229 {
230 	return false;
231 }
dma_supported(struct device * dev,u64 mask)232 static inline int dma_supported(struct device *dev, u64 mask)
233 {
234 	return 0;
235 }
dma_set_mask(struct device * dev,u64 mask)236 static inline int dma_set_mask(struct device *dev, u64 mask)
237 {
238 	return -EIO;
239 }
dma_set_coherent_mask(struct device * dev,u64 mask)240 static inline int dma_set_coherent_mask(struct device *dev, u64 mask)
241 {
242 	return -EIO;
243 }
dma_get_required_mask(struct device * dev)244 static inline u64 dma_get_required_mask(struct device *dev)
245 {
246 	return 0;
247 }
dma_max_mapping_size(struct device * dev)248 static inline size_t dma_max_mapping_size(struct device *dev)
249 {
250 	return 0;
251 }
dma_need_sync(struct device * dev,dma_addr_t dma_addr)252 static inline bool dma_need_sync(struct device *dev, dma_addr_t dma_addr)
253 {
254 	return false;
255 }
dma_get_merge_boundary(struct device * dev)256 static inline unsigned long dma_get_merge_boundary(struct device *dev)
257 {
258 	return 0;
259 }
260 #endif /* CONFIG_HAS_DMA */
261 
262 struct page *dma_alloc_pages(struct device *dev, size_t size,
263 		dma_addr_t *dma_handle, enum dma_data_direction dir, gfp_t gfp);
264 void dma_free_pages(struct device *dev, size_t size, struct page *page,
265 		dma_addr_t dma_handle, enum dma_data_direction dir);
266 void *dma_alloc_noncoherent(struct device *dev, size_t size,
267 		dma_addr_t *dma_handle, enum dma_data_direction dir, gfp_t gfp);
268 void dma_free_noncoherent(struct device *dev, size_t size, void *vaddr,
269 		dma_addr_t dma_handle, enum dma_data_direction dir);
270 
dma_map_single_attrs(struct device * dev,void * ptr,size_t size,enum dma_data_direction dir,unsigned long attrs)271 static inline dma_addr_t dma_map_single_attrs(struct device *dev, void *ptr,
272 		size_t size, enum dma_data_direction dir, unsigned long attrs)
273 {
274 	/* DMA must never operate on areas that might be remapped. */
275 	if (dev_WARN_ONCE(dev, is_vmalloc_addr(ptr),
276 			  "rejecting DMA map of vmalloc memory\n"))
277 		return DMA_MAPPING_ERROR;
278 	debug_dma_map_single(dev, ptr, size);
279 	return dma_map_page_attrs(dev, virt_to_page(ptr), offset_in_page(ptr),
280 			size, dir, attrs);
281 }
282 
dma_unmap_single_attrs(struct device * dev,dma_addr_t addr,size_t size,enum dma_data_direction dir,unsigned long attrs)283 static inline void dma_unmap_single_attrs(struct device *dev, dma_addr_t addr,
284 		size_t size, enum dma_data_direction dir, unsigned long attrs)
285 {
286 	return dma_unmap_page_attrs(dev, addr, size, dir, attrs);
287 }
288 
dma_sync_single_range_for_cpu(struct device * dev,dma_addr_t addr,unsigned long offset,size_t size,enum dma_data_direction dir)289 static inline void dma_sync_single_range_for_cpu(struct device *dev,
290 		dma_addr_t addr, unsigned long offset, size_t size,
291 		enum dma_data_direction dir)
292 {
293 	return dma_sync_single_for_cpu(dev, addr + offset, size, dir);
294 }
295 
dma_sync_single_range_for_device(struct device * dev,dma_addr_t addr,unsigned long offset,size_t size,enum dma_data_direction dir)296 static inline void dma_sync_single_range_for_device(struct device *dev,
297 		dma_addr_t addr, unsigned long offset, size_t size,
298 		enum dma_data_direction dir)
299 {
300 	return dma_sync_single_for_device(dev, addr + offset, size, dir);
301 }
302 
303 /**
304  * dma_map_sgtable - Map the given buffer for DMA
305  * @dev:	The device for which to perform the DMA operation
306  * @sgt:	The sg_table object describing the buffer
307  * @dir:	DMA direction
308  * @attrs:	Optional DMA attributes for the map operation
309  *
310  * Maps a buffer described by a scatterlist stored in the given sg_table
311  * object for the @dir DMA operation by the @dev device. After success the
312  * ownership for the buffer is transferred to the DMA domain.  One has to
313  * call dma_sync_sgtable_for_cpu() or dma_unmap_sgtable() to move the
314  * ownership of the buffer back to the CPU domain before touching the
315  * buffer by the CPU.
316  *
317  * Returns 0 on success or -EINVAL on error during mapping the buffer.
318  */
dma_map_sgtable(struct device * dev,struct sg_table * sgt,enum dma_data_direction dir,unsigned long attrs)319 static inline int dma_map_sgtable(struct device *dev, struct sg_table *sgt,
320 		enum dma_data_direction dir, unsigned long attrs)
321 {
322 	int nents;
323 
324 	nents = dma_map_sg_attrs(dev, sgt->sgl, sgt->orig_nents, dir, attrs);
325 	if (nents <= 0)
326 		return -EINVAL;
327 	sgt->nents = nents;
328 	return 0;
329 }
330 
331 /**
332  * dma_unmap_sgtable - Unmap the given buffer for DMA
333  * @dev:	The device for which to perform the DMA operation
334  * @sgt:	The sg_table object describing the buffer
335  * @dir:	DMA direction
336  * @attrs:	Optional DMA attributes for the unmap operation
337  *
338  * Unmaps a buffer described by a scatterlist stored in the given sg_table
339  * object for the @dir DMA operation by the @dev device. After this function
340  * the ownership of the buffer is transferred back to the CPU domain.
341  */
dma_unmap_sgtable(struct device * dev,struct sg_table * sgt,enum dma_data_direction dir,unsigned long attrs)342 static inline void dma_unmap_sgtable(struct device *dev, struct sg_table *sgt,
343 		enum dma_data_direction dir, unsigned long attrs)
344 {
345 	dma_unmap_sg_attrs(dev, sgt->sgl, sgt->orig_nents, dir, attrs);
346 }
347 
348 /**
349  * dma_sync_sgtable_for_cpu - Synchronize the given buffer for CPU access
350  * @dev:	The device for which to perform the DMA operation
351  * @sgt:	The sg_table object describing the buffer
352  * @dir:	DMA direction
353  *
354  * Performs the needed cache synchronization and moves the ownership of the
355  * buffer back to the CPU domain, so it is safe to perform any access to it
356  * by the CPU. Before doing any further DMA operations, one has to transfer
357  * the ownership of the buffer back to the DMA domain by calling the
358  * dma_sync_sgtable_for_device().
359  */
dma_sync_sgtable_for_cpu(struct device * dev,struct sg_table * sgt,enum dma_data_direction dir)360 static inline void dma_sync_sgtable_for_cpu(struct device *dev,
361 		struct sg_table *sgt, enum dma_data_direction dir)
362 {
363 	dma_sync_sg_for_cpu(dev, sgt->sgl, sgt->orig_nents, dir);
364 }
365 
366 /**
367  * dma_sync_sgtable_for_device - Synchronize the given buffer for DMA
368  * @dev:	The device for which to perform the DMA operation
369  * @sgt:	The sg_table object describing the buffer
370  * @dir:	DMA direction
371  *
372  * Performs the needed cache synchronization and moves the ownership of the
373  * buffer back to the DMA domain, so it is safe to perform the DMA operation.
374  * Once finished, one has to call dma_sync_sgtable_for_cpu() or
375  * dma_unmap_sgtable().
376  */
dma_sync_sgtable_for_device(struct device * dev,struct sg_table * sgt,enum dma_data_direction dir)377 static inline void dma_sync_sgtable_for_device(struct device *dev,
378 		struct sg_table *sgt, enum dma_data_direction dir)
379 {
380 	dma_sync_sg_for_device(dev, sgt->sgl, sgt->orig_nents, dir);
381 }
382 
383 #define dma_map_single(d, a, s, r) dma_map_single_attrs(d, a, s, r, 0)
384 #define dma_unmap_single(d, a, s, r) dma_unmap_single_attrs(d, a, s, r, 0)
385 #define dma_map_sg(d, s, n, r) dma_map_sg_attrs(d, s, n, r, 0)
386 #define dma_unmap_sg(d, s, n, r) dma_unmap_sg_attrs(d, s, n, r, 0)
387 #define dma_map_page(d, p, o, s, r) dma_map_page_attrs(d, p, o, s, r, 0)
388 #define dma_unmap_page(d, a, s, r) dma_unmap_page_attrs(d, a, s, r, 0)
389 #define dma_get_sgtable(d, t, v, h, s) dma_get_sgtable_attrs(d, t, v, h, s, 0)
390 #define dma_mmap_coherent(d, v, c, h, s) dma_mmap_attrs(d, v, c, h, s, 0)
391 
dma_alloc_coherent(struct device * dev,size_t size,dma_addr_t * dma_handle,gfp_t gfp)392 static inline void *dma_alloc_coherent(struct device *dev, size_t size,
393 		dma_addr_t *dma_handle, gfp_t gfp)
394 {
395 
396 	return dma_alloc_attrs(dev, size, dma_handle, gfp,
397 			(gfp & __GFP_NOWARN) ? DMA_ATTR_NO_WARN : 0);
398 }
399 
dma_free_coherent(struct device * dev,size_t size,void * cpu_addr,dma_addr_t dma_handle)400 static inline void dma_free_coherent(struct device *dev, size_t size,
401 		void *cpu_addr, dma_addr_t dma_handle)
402 {
403 	return dma_free_attrs(dev, size, cpu_addr, dma_handle, 0);
404 }
405 
406 
dma_get_mask(struct device * dev)407 static inline u64 dma_get_mask(struct device *dev)
408 {
409 	if (dev->dma_mask && *dev->dma_mask)
410 		return *dev->dma_mask;
411 	return DMA_BIT_MASK(32);
412 }
413 
414 /*
415  * Set both the DMA mask and the coherent DMA mask to the same thing.
416  * Note that we don't check the return value from dma_set_coherent_mask()
417  * as the DMA API guarantees that the coherent DMA mask can be set to
418  * the same or smaller than the streaming DMA mask.
419  */
dma_set_mask_and_coherent(struct device * dev,u64 mask)420 static inline int dma_set_mask_and_coherent(struct device *dev, u64 mask)
421 {
422 	int rc = dma_set_mask(dev, mask);
423 	if (rc == 0)
424 		dma_set_coherent_mask(dev, mask);
425 	return rc;
426 }
427 
428 /*
429  * Similar to the above, except it deals with the case where the device
430  * does not have dev->dma_mask appropriately setup.
431  */
dma_coerce_mask_and_coherent(struct device * dev,u64 mask)432 static inline int dma_coerce_mask_and_coherent(struct device *dev, u64 mask)
433 {
434 	dev->dma_mask = &dev->coherent_dma_mask;
435 	return dma_set_mask_and_coherent(dev, mask);
436 }
437 
438 /**
439  * dma_addressing_limited - return if the device is addressing limited
440  * @dev:	device to check
441  *
442  * Return %true if the devices DMA mask is too small to address all memory in
443  * the system, else %false.  Lack of addressing bits is the prime reason for
444  * bounce buffering, but might not be the only one.
445  */
dma_addressing_limited(struct device * dev)446 static inline bool dma_addressing_limited(struct device *dev)
447 {
448 	return min_not_zero(dma_get_mask(dev), dev->bus_dma_limit) <
449 			    dma_get_required_mask(dev);
450 }
451 
dma_get_max_seg_size(struct device * dev)452 static inline unsigned int dma_get_max_seg_size(struct device *dev)
453 {
454 	if (dev->dma_parms && dev->dma_parms->max_segment_size)
455 		return dev->dma_parms->max_segment_size;
456 	return SZ_64K;
457 }
458 
dma_set_max_seg_size(struct device * dev,unsigned int size)459 static inline int dma_set_max_seg_size(struct device *dev, unsigned int size)
460 {
461 	if (dev->dma_parms) {
462 		dev->dma_parms->max_segment_size = size;
463 		return 0;
464 	}
465 	return -EIO;
466 }
467 
dma_get_seg_boundary(struct device * dev)468 static inline unsigned long dma_get_seg_boundary(struct device *dev)
469 {
470 	if (dev->dma_parms && dev->dma_parms->segment_boundary_mask)
471 		return dev->dma_parms->segment_boundary_mask;
472 	return ULONG_MAX;
473 }
474 
475 /**
476  * dma_get_seg_boundary_nr_pages - return the segment boundary in "page" units
477  * @dev: device to guery the boundary for
478  * @page_shift: ilog() of the IOMMU page size
479  *
480  * Return the segment boundary in IOMMU page units (which may be different from
481  * the CPU page size) for the passed in device.
482  *
483  * If @dev is NULL a boundary of U32_MAX is assumed, this case is just for
484  * non-DMA API callers.
485  */
dma_get_seg_boundary_nr_pages(struct device * dev,unsigned int page_shift)486 static inline unsigned long dma_get_seg_boundary_nr_pages(struct device *dev,
487 		unsigned int page_shift)
488 {
489 	if (!dev)
490 		return (U32_MAX >> page_shift) + 1;
491 	return (dma_get_seg_boundary(dev) >> page_shift) + 1;
492 }
493 
dma_set_seg_boundary(struct device * dev,unsigned long mask)494 static inline int dma_set_seg_boundary(struct device *dev, unsigned long mask)
495 {
496 	if (dev->dma_parms) {
497 		dev->dma_parms->segment_boundary_mask = mask;
498 		return 0;
499 	}
500 	return -EIO;
501 }
502 
dma_get_cache_alignment(void)503 static inline int dma_get_cache_alignment(void)
504 {
505 #ifdef ARCH_DMA_MINALIGN
506 	return ARCH_DMA_MINALIGN;
507 #endif
508 	return 1;
509 }
510 
dmam_alloc_coherent(struct device * dev,size_t size,dma_addr_t * dma_handle,gfp_t gfp)511 static inline void *dmam_alloc_coherent(struct device *dev, size_t size,
512 		dma_addr_t *dma_handle, gfp_t gfp)
513 {
514 	return dmam_alloc_attrs(dev, size, dma_handle, gfp,
515 			(gfp & __GFP_NOWARN) ? DMA_ATTR_NO_WARN : 0);
516 }
517 
dma_alloc_wc(struct device * dev,size_t size,dma_addr_t * dma_addr,gfp_t gfp)518 static inline void *dma_alloc_wc(struct device *dev, size_t size,
519 				 dma_addr_t *dma_addr, gfp_t gfp)
520 {
521 	unsigned long attrs = DMA_ATTR_WRITE_COMBINE;
522 
523 	if (gfp & __GFP_NOWARN)
524 		attrs |= DMA_ATTR_NO_WARN;
525 
526 	return dma_alloc_attrs(dev, size, dma_addr, gfp, attrs);
527 }
528 
dma_free_wc(struct device * dev,size_t size,void * cpu_addr,dma_addr_t dma_addr)529 static inline void dma_free_wc(struct device *dev, size_t size,
530 			       void *cpu_addr, dma_addr_t dma_addr)
531 {
532 	return dma_free_attrs(dev, size, cpu_addr, dma_addr,
533 			      DMA_ATTR_WRITE_COMBINE);
534 }
535 
dma_mmap_wc(struct device * dev,struct vm_area_struct * vma,void * cpu_addr,dma_addr_t dma_addr,size_t size)536 static inline int dma_mmap_wc(struct device *dev,
537 			      struct vm_area_struct *vma,
538 			      void *cpu_addr, dma_addr_t dma_addr,
539 			      size_t size)
540 {
541 	return dma_mmap_attrs(dev, vma, cpu_addr, dma_addr, size,
542 			      DMA_ATTR_WRITE_COMBINE);
543 }
544 
545 #ifdef CONFIG_NEED_DMA_MAP_STATE
546 #define DEFINE_DMA_UNMAP_ADDR(ADDR_NAME)        dma_addr_t ADDR_NAME
547 #define DEFINE_DMA_UNMAP_LEN(LEN_NAME)          __u32 LEN_NAME
548 #define dma_unmap_addr(PTR, ADDR_NAME)           ((PTR)->ADDR_NAME)
549 #define dma_unmap_addr_set(PTR, ADDR_NAME, VAL)  (((PTR)->ADDR_NAME) = (VAL))
550 #define dma_unmap_len(PTR, LEN_NAME)             ((PTR)->LEN_NAME)
551 #define dma_unmap_len_set(PTR, LEN_NAME, VAL)    (((PTR)->LEN_NAME) = (VAL))
552 #else
553 #define DEFINE_DMA_UNMAP_ADDR(ADDR_NAME)
554 #define DEFINE_DMA_UNMAP_LEN(LEN_NAME)
555 #define dma_unmap_addr(PTR, ADDR_NAME)           (0)
556 #define dma_unmap_addr_set(PTR, ADDR_NAME, VAL)  do { } while (0)
557 #define dma_unmap_len(PTR, LEN_NAME)             (0)
558 #define dma_unmap_len_set(PTR, LEN_NAME, VAL)    do { } while (0)
559 #endif
560 
561 /*
562  * Legacy interface to set up the dma offset map.  Drivers really should not
563  * actually use it, but we have a few legacy cases left.
564  */
565 int dma_direct_set_offset(struct device *dev, phys_addr_t cpu_start,
566 		dma_addr_t dma_start, u64 size);
567 
568 extern const struct dma_map_ops dma_virt_ops;
569 
570 #endif /* _LINUX_DMA_MAPPING_H */
571