Linux kernel mirror (for testing)
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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
79void debug_dma_mapping_error(struct device *dev, dma_addr_t dma_addr);
80void debug_dma_map_single(struct device *dev, const void *addr,
81 unsigned long len);
82#else
83static inline void debug_dma_mapping_error(struct device *dev,
84 dma_addr_t dma_addr)
85{
86}
87static 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
94static 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
103dma_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);
106void dma_unmap_page_attrs(struct device *dev, dma_addr_t addr, size_t size,
107 enum dma_data_direction dir, unsigned long attrs);
108int dma_map_sg_attrs(struct device *dev, struct scatterlist *sg, int nents,
109 enum dma_data_direction dir, unsigned long attrs);
110void dma_unmap_sg_attrs(struct device *dev, struct scatterlist *sg,
111 int nents, enum dma_data_direction dir,
112 unsigned long attrs);
113dma_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);
115void dma_unmap_resource(struct device *dev, dma_addr_t addr, size_t size,
116 enum dma_data_direction dir, unsigned long attrs);
117void dma_sync_single_for_cpu(struct device *dev, dma_addr_t addr, size_t size,
118 enum dma_data_direction dir);
119void dma_sync_single_for_device(struct device *dev, dma_addr_t addr,
120 size_t size, enum dma_data_direction dir);
121void dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg,
122 int nelems, enum dma_data_direction dir);
123void dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg,
124 int nelems, enum dma_data_direction dir);
125void *dma_alloc_attrs(struct device *dev, size_t size, dma_addr_t *dma_handle,
126 gfp_t flag, unsigned long attrs);
127void dma_free_attrs(struct device *dev, size_t size, void *cpu_addr,
128 dma_addr_t dma_handle, unsigned long attrs);
129void *dmam_alloc_attrs(struct device *dev, size_t size, dma_addr_t *dma_handle,
130 gfp_t gfp, unsigned long attrs);
131void dmam_free_coherent(struct device *dev, size_t size, void *vaddr,
132 dma_addr_t dma_handle);
133int 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);
136int 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);
139bool dma_can_mmap(struct device *dev);
140int dma_supported(struct device *dev, u64 mask);
141int dma_set_mask(struct device *dev, u64 mask);
142int dma_set_coherent_mask(struct device *dev, u64 mask);
143u64 dma_get_required_mask(struct device *dev);
144size_t dma_max_mapping_size(struct device *dev);
145bool dma_need_sync(struct device *dev, dma_addr_t dma_addr);
146unsigned long dma_get_merge_boundary(struct device *dev);
147#else /* CONFIG_HAS_DMA */
148static 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}
154static 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}
158static 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}
163static 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}
168static 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}
174static 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}
178static 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}
182static 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}
186static inline void dma_sync_sg_for_cpu(struct device *dev,
187 struct scatterlist *sg, int nelems, enum dma_data_direction dir)
188{
189}
190static inline void dma_sync_sg_for_device(struct device *dev,
191 struct scatterlist *sg, int nelems, enum dma_data_direction dir)
192{
193}
194static inline int dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
195{
196 return -ENOMEM;
197}
198static 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}
203static void dma_free_attrs(struct device *dev, size_t size, void *cpu_addr,
204 dma_addr_t dma_handle, unsigned long attrs)
205{
206}
207static 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}
212static inline void dmam_free_coherent(struct device *dev, size_t size,
213 void *vaddr, dma_addr_t dma_handle)
214{
215}
216static 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}
222static 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}
228static inline bool dma_can_mmap(struct device *dev)
229{
230 return false;
231}
232static inline int dma_supported(struct device *dev, u64 mask)
233{
234 return 0;
235}
236static inline int dma_set_mask(struct device *dev, u64 mask)
237{
238 return -EIO;
239}
240static inline int dma_set_coherent_mask(struct device *dev, u64 mask)
241{
242 return -EIO;
243}
244static inline u64 dma_get_required_mask(struct device *dev)
245{
246 return 0;
247}
248static inline size_t dma_max_mapping_size(struct device *dev)
249{
250 return 0;
251}
252static inline bool dma_need_sync(struct device *dev, dma_addr_t dma_addr)
253{
254 return false;
255}
256static inline unsigned long dma_get_merge_boundary(struct device *dev)
257{
258 return 0;
259}
260#endif /* CONFIG_HAS_DMA */
261
262struct page *dma_alloc_pages(struct device *dev, size_t size,
263 dma_addr_t *dma_handle, enum dma_data_direction dir, gfp_t gfp);
264void dma_free_pages(struct device *dev, size_t size, struct page *page,
265 dma_addr_t dma_handle, enum dma_data_direction dir);
266
267static inline void *dma_alloc_noncoherent(struct device *dev, size_t size,
268 dma_addr_t *dma_handle, enum dma_data_direction dir, gfp_t gfp)
269{
270 struct page *page = dma_alloc_pages(dev, size, dma_handle, dir, gfp);
271 return page ? page_address(page) : NULL;
272}
273
274static inline void dma_free_noncoherent(struct device *dev, size_t size,
275 void *vaddr, dma_addr_t dma_handle, enum dma_data_direction dir)
276{
277 dma_free_pages(dev, size, virt_to_page(vaddr), dma_handle, dir);
278}
279
280static inline dma_addr_t dma_map_single_attrs(struct device *dev, void *ptr,
281 size_t size, enum dma_data_direction dir, unsigned long attrs)
282{
283 /* DMA must never operate on areas that might be remapped. */
284 if (dev_WARN_ONCE(dev, is_vmalloc_addr(ptr),
285 "rejecting DMA map of vmalloc memory\n"))
286 return DMA_MAPPING_ERROR;
287 debug_dma_map_single(dev, ptr, size);
288 return dma_map_page_attrs(dev, virt_to_page(ptr), offset_in_page(ptr),
289 size, dir, attrs);
290}
291
292static inline void dma_unmap_single_attrs(struct device *dev, dma_addr_t addr,
293 size_t size, enum dma_data_direction dir, unsigned long attrs)
294{
295 return dma_unmap_page_attrs(dev, addr, size, dir, attrs);
296}
297
298static inline void dma_sync_single_range_for_cpu(struct device *dev,
299 dma_addr_t addr, unsigned long offset, size_t size,
300 enum dma_data_direction dir)
301{
302 return dma_sync_single_for_cpu(dev, addr + offset, size, dir);
303}
304
305static inline void dma_sync_single_range_for_device(struct device *dev,
306 dma_addr_t addr, unsigned long offset, size_t size,
307 enum dma_data_direction dir)
308{
309 return dma_sync_single_for_device(dev, addr + offset, size, dir);
310}
311
312/**
313 * dma_map_sgtable - Map the given buffer for DMA
314 * @dev: The device for which to perform the DMA operation
315 * @sgt: The sg_table object describing the buffer
316 * @dir: DMA direction
317 * @attrs: Optional DMA attributes for the map operation
318 *
319 * Maps a buffer described by a scatterlist stored in the given sg_table
320 * object for the @dir DMA operation by the @dev device. After success the
321 * ownership for the buffer is transferred to the DMA domain. One has to
322 * call dma_sync_sgtable_for_cpu() or dma_unmap_sgtable() to move the
323 * ownership of the buffer back to the CPU domain before touching the
324 * buffer by the CPU.
325 *
326 * Returns 0 on success or -EINVAL on error during mapping the buffer.
327 */
328static inline int dma_map_sgtable(struct device *dev, struct sg_table *sgt,
329 enum dma_data_direction dir, unsigned long attrs)
330{
331 int nents;
332
333 nents = dma_map_sg_attrs(dev, sgt->sgl, sgt->orig_nents, dir, attrs);
334 if (nents <= 0)
335 return -EINVAL;
336 sgt->nents = nents;
337 return 0;
338}
339
340/**
341 * dma_unmap_sgtable - Unmap the given buffer for DMA
342 * @dev: The device for which to perform the DMA operation
343 * @sgt: The sg_table object describing the buffer
344 * @dir: DMA direction
345 * @attrs: Optional DMA attributes for the unmap operation
346 *
347 * Unmaps a buffer described by a scatterlist stored in the given sg_table
348 * object for the @dir DMA operation by the @dev device. After this function
349 * the ownership of the buffer is transferred back to the CPU domain.
350 */
351static inline void dma_unmap_sgtable(struct device *dev, struct sg_table *sgt,
352 enum dma_data_direction dir, unsigned long attrs)
353{
354 dma_unmap_sg_attrs(dev, sgt->sgl, sgt->orig_nents, dir, attrs);
355}
356
357/**
358 * dma_sync_sgtable_for_cpu - Synchronize the given buffer for CPU access
359 * @dev: The device for which to perform the DMA operation
360 * @sgt: The sg_table object describing the buffer
361 * @dir: DMA direction
362 *
363 * Performs the needed cache synchronization and moves the ownership of the
364 * buffer back to the CPU domain, so it is safe to perform any access to it
365 * by the CPU. Before doing any further DMA operations, one has to transfer
366 * the ownership of the buffer back to the DMA domain by calling the
367 * dma_sync_sgtable_for_device().
368 */
369static inline void dma_sync_sgtable_for_cpu(struct device *dev,
370 struct sg_table *sgt, enum dma_data_direction dir)
371{
372 dma_sync_sg_for_cpu(dev, sgt->sgl, sgt->orig_nents, dir);
373}
374
375/**
376 * dma_sync_sgtable_for_device - Synchronize the given buffer for DMA
377 * @dev: The device for which to perform the DMA operation
378 * @sgt: The sg_table object describing the buffer
379 * @dir: DMA direction
380 *
381 * Performs the needed cache synchronization and moves the ownership of the
382 * buffer back to the DMA domain, so it is safe to perform the DMA operation.
383 * Once finished, one has to call dma_sync_sgtable_for_cpu() or
384 * dma_unmap_sgtable().
385 */
386static inline void dma_sync_sgtable_for_device(struct device *dev,
387 struct sg_table *sgt, enum dma_data_direction dir)
388{
389 dma_sync_sg_for_device(dev, sgt->sgl, sgt->orig_nents, dir);
390}
391
392#define dma_map_single(d, a, s, r) dma_map_single_attrs(d, a, s, r, 0)
393#define dma_unmap_single(d, a, s, r) dma_unmap_single_attrs(d, a, s, r, 0)
394#define dma_map_sg(d, s, n, r) dma_map_sg_attrs(d, s, n, r, 0)
395#define dma_unmap_sg(d, s, n, r) dma_unmap_sg_attrs(d, s, n, r, 0)
396#define dma_map_page(d, p, o, s, r) dma_map_page_attrs(d, p, o, s, r, 0)
397#define dma_unmap_page(d, a, s, r) dma_unmap_page_attrs(d, a, s, r, 0)
398#define dma_get_sgtable(d, t, v, h, s) dma_get_sgtable_attrs(d, t, v, h, s, 0)
399#define dma_mmap_coherent(d, v, c, h, s) dma_mmap_attrs(d, v, c, h, s, 0)
400
401static inline void *dma_alloc_coherent(struct device *dev, size_t size,
402 dma_addr_t *dma_handle, gfp_t gfp)
403{
404
405 return dma_alloc_attrs(dev, size, dma_handle, gfp,
406 (gfp & __GFP_NOWARN) ? DMA_ATTR_NO_WARN : 0);
407}
408
409static inline void dma_free_coherent(struct device *dev, size_t size,
410 void *cpu_addr, dma_addr_t dma_handle)
411{
412 return dma_free_attrs(dev, size, cpu_addr, dma_handle, 0);
413}
414
415
416static inline u64 dma_get_mask(struct device *dev)
417{
418 if (dev->dma_mask && *dev->dma_mask)
419 return *dev->dma_mask;
420 return DMA_BIT_MASK(32);
421}
422
423/*
424 * Set both the DMA mask and the coherent DMA mask to the same thing.
425 * Note that we don't check the return value from dma_set_coherent_mask()
426 * as the DMA API guarantees that the coherent DMA mask can be set to
427 * the same or smaller than the streaming DMA mask.
428 */
429static inline int dma_set_mask_and_coherent(struct device *dev, u64 mask)
430{
431 int rc = dma_set_mask(dev, mask);
432 if (rc == 0)
433 dma_set_coherent_mask(dev, mask);
434 return rc;
435}
436
437/*
438 * Similar to the above, except it deals with the case where the device
439 * does not have dev->dma_mask appropriately setup.
440 */
441static inline int dma_coerce_mask_and_coherent(struct device *dev, u64 mask)
442{
443 dev->dma_mask = &dev->coherent_dma_mask;
444 return dma_set_mask_and_coherent(dev, mask);
445}
446
447/**
448 * dma_addressing_limited - return if the device is addressing limited
449 * @dev: device to check
450 *
451 * Return %true if the devices DMA mask is too small to address all memory in
452 * the system, else %false. Lack of addressing bits is the prime reason for
453 * bounce buffering, but might not be the only one.
454 */
455static inline bool dma_addressing_limited(struct device *dev)
456{
457 return min_not_zero(dma_get_mask(dev), dev->bus_dma_limit) <
458 dma_get_required_mask(dev);
459}
460
461static inline unsigned int dma_get_max_seg_size(struct device *dev)
462{
463 if (dev->dma_parms && dev->dma_parms->max_segment_size)
464 return dev->dma_parms->max_segment_size;
465 return SZ_64K;
466}
467
468static inline int dma_set_max_seg_size(struct device *dev, unsigned int size)
469{
470 if (dev->dma_parms) {
471 dev->dma_parms->max_segment_size = size;
472 return 0;
473 }
474 return -EIO;
475}
476
477static inline unsigned long dma_get_seg_boundary(struct device *dev)
478{
479 if (dev->dma_parms && dev->dma_parms->segment_boundary_mask)
480 return dev->dma_parms->segment_boundary_mask;
481 return ULONG_MAX;
482}
483
484/**
485 * dma_get_seg_boundary_nr_pages - return the segment boundary in "page" units
486 * @dev: device to guery the boundary for
487 * @page_shift: ilog() of the IOMMU page size
488 *
489 * Return the segment boundary in IOMMU page units (which may be different from
490 * the CPU page size) for the passed in device.
491 *
492 * If @dev is NULL a boundary of U32_MAX is assumed, this case is just for
493 * non-DMA API callers.
494 */
495static inline unsigned long dma_get_seg_boundary_nr_pages(struct device *dev,
496 unsigned int page_shift)
497{
498 if (!dev)
499 return (U32_MAX >> page_shift) + 1;
500 return (dma_get_seg_boundary(dev) >> page_shift) + 1;
501}
502
503static inline int dma_set_seg_boundary(struct device *dev, unsigned long mask)
504{
505 if (dev->dma_parms) {
506 dev->dma_parms->segment_boundary_mask = mask;
507 return 0;
508 }
509 return -EIO;
510}
511
512static inline unsigned int dma_get_min_align_mask(struct device *dev)
513{
514 if (dev->dma_parms)
515 return dev->dma_parms->min_align_mask;
516 return 0;
517}
518
519static inline int dma_set_min_align_mask(struct device *dev,
520 unsigned int min_align_mask)
521{
522 if (WARN_ON_ONCE(!dev->dma_parms))
523 return -EIO;
524 dev->dma_parms->min_align_mask = min_align_mask;
525 return 0;
526}
527
528static inline int dma_get_cache_alignment(void)
529{
530#ifdef ARCH_DMA_MINALIGN
531 return ARCH_DMA_MINALIGN;
532#endif
533 return 1;
534}
535
536static inline void *dmam_alloc_coherent(struct device *dev, size_t size,
537 dma_addr_t *dma_handle, gfp_t gfp)
538{
539 return dmam_alloc_attrs(dev, size, dma_handle, gfp,
540 (gfp & __GFP_NOWARN) ? DMA_ATTR_NO_WARN : 0);
541}
542
543static inline void *dma_alloc_wc(struct device *dev, size_t size,
544 dma_addr_t *dma_addr, gfp_t gfp)
545{
546 unsigned long attrs = DMA_ATTR_WRITE_COMBINE;
547
548 if (gfp & __GFP_NOWARN)
549 attrs |= DMA_ATTR_NO_WARN;
550
551 return dma_alloc_attrs(dev, size, dma_addr, gfp, attrs);
552}
553
554static inline void dma_free_wc(struct device *dev, size_t size,
555 void *cpu_addr, dma_addr_t dma_addr)
556{
557 return dma_free_attrs(dev, size, cpu_addr, dma_addr,
558 DMA_ATTR_WRITE_COMBINE);
559}
560
561static inline int dma_mmap_wc(struct device *dev,
562 struct vm_area_struct *vma,
563 void *cpu_addr, dma_addr_t dma_addr,
564 size_t size)
565{
566 return dma_mmap_attrs(dev, vma, cpu_addr, dma_addr, size,
567 DMA_ATTR_WRITE_COMBINE);
568}
569
570#ifdef CONFIG_NEED_DMA_MAP_STATE
571#define DEFINE_DMA_UNMAP_ADDR(ADDR_NAME) dma_addr_t ADDR_NAME
572#define DEFINE_DMA_UNMAP_LEN(LEN_NAME) __u32 LEN_NAME
573#define dma_unmap_addr(PTR, ADDR_NAME) ((PTR)->ADDR_NAME)
574#define dma_unmap_addr_set(PTR, ADDR_NAME, VAL) (((PTR)->ADDR_NAME) = (VAL))
575#define dma_unmap_len(PTR, LEN_NAME) ((PTR)->LEN_NAME)
576#define dma_unmap_len_set(PTR, LEN_NAME, VAL) (((PTR)->LEN_NAME) = (VAL))
577#else
578#define DEFINE_DMA_UNMAP_ADDR(ADDR_NAME)
579#define DEFINE_DMA_UNMAP_LEN(LEN_NAME)
580#define dma_unmap_addr(PTR, ADDR_NAME) (0)
581#define dma_unmap_addr_set(PTR, ADDR_NAME, VAL) do { } while (0)
582#define dma_unmap_len(PTR, LEN_NAME) (0)
583#define dma_unmap_len_set(PTR, LEN_NAME, VAL) do { } while (0)
584#endif
585
586#endif /* _LINUX_DMA_MAPPING_H */