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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * arch-independent dma-mapping routines
4 *
5 * Copyright (c) 2006 SUSE Linux Products GmbH
6 * Copyright (c) 2006 Tejun Heo <teheo@suse.de>
7 */
8#include <linux/memblock.h> /* for max_pfn */
9#include <linux/acpi.h>
10#include <linux/dma-direct.h>
11#include <linux/dma-noncoherent.h>
12#include <linux/export.h>
13#include <linux/gfp.h>
14#include <linux/of_device.h>
15#include <linux/slab.h>
16#include <linux/vmalloc.h>
17
18/*
19 * Managed DMA API
20 */
21struct dma_devres {
22 size_t size;
23 void *vaddr;
24 dma_addr_t dma_handle;
25 unsigned long attrs;
26};
27
28static void dmam_release(struct device *dev, void *res)
29{
30 struct dma_devres *this = res;
31
32 dma_free_attrs(dev, this->size, this->vaddr, this->dma_handle,
33 this->attrs);
34}
35
36static int dmam_match(struct device *dev, void *res, void *match_data)
37{
38 struct dma_devres *this = res, *match = match_data;
39
40 if (this->vaddr == match->vaddr) {
41 WARN_ON(this->size != match->size ||
42 this->dma_handle != match->dma_handle);
43 return 1;
44 }
45 return 0;
46}
47
48/**
49 * dmam_free_coherent - Managed dma_free_coherent()
50 * @dev: Device to free coherent memory for
51 * @size: Size of allocation
52 * @vaddr: Virtual address of the memory to free
53 * @dma_handle: DMA handle of the memory to free
54 *
55 * Managed dma_free_coherent().
56 */
57void dmam_free_coherent(struct device *dev, size_t size, void *vaddr,
58 dma_addr_t dma_handle)
59{
60 struct dma_devres match_data = { size, vaddr, dma_handle };
61
62 dma_free_coherent(dev, size, vaddr, dma_handle);
63 WARN_ON(devres_destroy(dev, dmam_release, dmam_match, &match_data));
64}
65EXPORT_SYMBOL(dmam_free_coherent);
66
67/**
68 * dmam_alloc_attrs - Managed dma_alloc_attrs()
69 * @dev: Device to allocate non_coherent memory for
70 * @size: Size of allocation
71 * @dma_handle: Out argument for allocated DMA handle
72 * @gfp: Allocation flags
73 * @attrs: Flags in the DMA_ATTR_* namespace.
74 *
75 * Managed dma_alloc_attrs(). Memory allocated using this function will be
76 * automatically released on driver detach.
77 *
78 * RETURNS:
79 * Pointer to allocated memory on success, NULL on failure.
80 */
81void *dmam_alloc_attrs(struct device *dev, size_t size, dma_addr_t *dma_handle,
82 gfp_t gfp, unsigned long attrs)
83{
84 struct dma_devres *dr;
85 void *vaddr;
86
87 dr = devres_alloc(dmam_release, sizeof(*dr), gfp);
88 if (!dr)
89 return NULL;
90
91 vaddr = dma_alloc_attrs(dev, size, dma_handle, gfp, attrs);
92 if (!vaddr) {
93 devres_free(dr);
94 return NULL;
95 }
96
97 dr->vaddr = vaddr;
98 dr->dma_handle = *dma_handle;
99 dr->size = size;
100 dr->attrs = attrs;
101
102 devres_add(dev, dr);
103
104 return vaddr;
105}
106EXPORT_SYMBOL(dmam_alloc_attrs);
107
108/*
109 * Create scatter-list for the already allocated DMA buffer.
110 */
111int dma_common_get_sgtable(struct device *dev, struct sg_table *sgt,
112 void *cpu_addr, dma_addr_t dma_addr, size_t size,
113 unsigned long attrs)
114{
115 struct page *page;
116 int ret;
117
118 if (!dev_is_dma_coherent(dev)) {
119 unsigned long pfn;
120
121 if (!IS_ENABLED(CONFIG_ARCH_HAS_DMA_COHERENT_TO_PFN))
122 return -ENXIO;
123
124 /* If the PFN is not valid, we do not have a struct page */
125 pfn = arch_dma_coherent_to_pfn(dev, cpu_addr, dma_addr);
126 if (!pfn_valid(pfn))
127 return -ENXIO;
128 page = pfn_to_page(pfn);
129 } else {
130 page = virt_to_page(cpu_addr);
131 }
132
133 ret = sg_alloc_table(sgt, 1, GFP_KERNEL);
134 if (!ret)
135 sg_set_page(sgt->sgl, page, PAGE_ALIGN(size), 0);
136 return ret;
137}
138
139/*
140 * The whole dma_get_sgtable() idea is fundamentally unsafe - it seems
141 * that the intention is to allow exporting memory allocated via the
142 * coherent DMA APIs through the dma_buf API, which only accepts a
143 * scattertable. This presents a couple of problems:
144 * 1. Not all memory allocated via the coherent DMA APIs is backed by
145 * a struct page
146 * 2. Passing coherent DMA memory into the streaming APIs is not allowed
147 * as we will try to flush the memory through a different alias to that
148 * actually being used (and the flushes are redundant.)
149 */
150int dma_get_sgtable_attrs(struct device *dev, struct sg_table *sgt,
151 void *cpu_addr, dma_addr_t dma_addr, size_t size,
152 unsigned long attrs)
153{
154 const struct dma_map_ops *ops = get_dma_ops(dev);
155
156 if (dma_is_direct(ops))
157 return dma_common_get_sgtable(dev, sgt, cpu_addr, dma_addr,
158 size, attrs);
159 if (!ops->get_sgtable)
160 return -ENXIO;
161 return ops->get_sgtable(dev, sgt, cpu_addr, dma_addr, size, attrs);
162}
163EXPORT_SYMBOL(dma_get_sgtable_attrs);
164
165#ifdef CONFIG_MMU
166/*
167 * Return the page attributes used for mapping dma_alloc_* memory, either in
168 * kernel space if remapping is needed, or to userspace through dma_mmap_*.
169 */
170pgprot_t dma_pgprot(struct device *dev, pgprot_t prot, unsigned long attrs)
171{
172 if (dev_is_dma_coherent(dev) ||
173 (IS_ENABLED(CONFIG_DMA_NONCOHERENT_CACHE_SYNC) &&
174 (attrs & DMA_ATTR_NON_CONSISTENT)))
175 return prot;
176#ifdef CONFIG_ARCH_HAS_DMA_WRITE_COMBINE
177 if (attrs & DMA_ATTR_WRITE_COMBINE)
178 return pgprot_writecombine(prot);
179#endif
180 return pgprot_dmacoherent(prot);
181}
182#endif /* CONFIG_MMU */
183
184/*
185 * Create userspace mapping for the DMA-coherent memory.
186 */
187int dma_common_mmap(struct device *dev, struct vm_area_struct *vma,
188 void *cpu_addr, dma_addr_t dma_addr, size_t size,
189 unsigned long attrs)
190{
191#ifdef CONFIG_MMU
192 unsigned long user_count = vma_pages(vma);
193 unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT;
194 unsigned long off = vma->vm_pgoff;
195 unsigned long pfn;
196 int ret = -ENXIO;
197
198 vma->vm_page_prot = dma_pgprot(dev, vma->vm_page_prot, attrs);
199
200 if (dma_mmap_from_dev_coherent(dev, vma, cpu_addr, size, &ret))
201 return ret;
202
203 if (off >= count || user_count > count - off)
204 return -ENXIO;
205
206 if (!dev_is_dma_coherent(dev)) {
207 if (!IS_ENABLED(CONFIG_ARCH_HAS_DMA_COHERENT_TO_PFN))
208 return -ENXIO;
209
210 /* If the PFN is not valid, we do not have a struct page */
211 pfn = arch_dma_coherent_to_pfn(dev, cpu_addr, dma_addr);
212 if (!pfn_valid(pfn))
213 return -ENXIO;
214 } else {
215 pfn = page_to_pfn(virt_to_page(cpu_addr));
216 }
217
218 return remap_pfn_range(vma, vma->vm_start, pfn + vma->vm_pgoff,
219 user_count << PAGE_SHIFT, vma->vm_page_prot);
220#else
221 return -ENXIO;
222#endif /* CONFIG_MMU */
223}
224
225/**
226 * dma_can_mmap - check if a given device supports dma_mmap_*
227 * @dev: device to check
228 *
229 * Returns %true if @dev supports dma_mmap_coherent() and dma_mmap_attrs() to
230 * map DMA allocations to userspace.
231 */
232bool dma_can_mmap(struct device *dev)
233{
234 const struct dma_map_ops *ops = get_dma_ops(dev);
235
236 if (dma_is_direct(ops)) {
237 return IS_ENABLED(CONFIG_MMU) &&
238 (dev_is_dma_coherent(dev) ||
239 IS_ENABLED(CONFIG_ARCH_HAS_DMA_COHERENT_TO_PFN));
240 }
241
242 return ops->mmap != NULL;
243}
244EXPORT_SYMBOL_GPL(dma_can_mmap);
245
246/**
247 * dma_mmap_attrs - map a coherent DMA allocation into user space
248 * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
249 * @vma: vm_area_struct describing requested user mapping
250 * @cpu_addr: kernel CPU-view address returned from dma_alloc_attrs
251 * @dma_addr: device-view address returned from dma_alloc_attrs
252 * @size: size of memory originally requested in dma_alloc_attrs
253 * @attrs: attributes of mapping properties requested in dma_alloc_attrs
254 *
255 * Map a coherent DMA buffer previously allocated by dma_alloc_attrs into user
256 * space. The coherent DMA buffer must not be freed by the driver until the
257 * user space mapping has been released.
258 */
259int dma_mmap_attrs(struct device *dev, struct vm_area_struct *vma,
260 void *cpu_addr, dma_addr_t dma_addr, size_t size,
261 unsigned long attrs)
262{
263 const struct dma_map_ops *ops = get_dma_ops(dev);
264
265 if (dma_is_direct(ops))
266 return dma_common_mmap(dev, vma, cpu_addr, dma_addr, size,
267 attrs);
268 if (!ops->mmap)
269 return -ENXIO;
270 return ops->mmap(dev, vma, cpu_addr, dma_addr, size, attrs);
271}
272EXPORT_SYMBOL(dma_mmap_attrs);
273
274u64 dma_get_required_mask(struct device *dev)
275{
276 const struct dma_map_ops *ops = get_dma_ops(dev);
277
278 if (dma_is_direct(ops))
279 return dma_direct_get_required_mask(dev);
280 if (ops->get_required_mask)
281 return ops->get_required_mask(dev);
282
283 /*
284 * We require every DMA ops implementation to at least support a 32-bit
285 * DMA mask (and use bounce buffering if that isn't supported in
286 * hardware). As the direct mapping code has its own routine to
287 * actually report an optimal mask we default to 32-bit here as that
288 * is the right thing for most IOMMUs, and at least not actively
289 * harmful in general.
290 */
291 return DMA_BIT_MASK(32);
292}
293EXPORT_SYMBOL_GPL(dma_get_required_mask);
294
295void *dma_alloc_attrs(struct device *dev, size_t size, dma_addr_t *dma_handle,
296 gfp_t flag, unsigned long attrs)
297{
298 const struct dma_map_ops *ops = get_dma_ops(dev);
299 void *cpu_addr;
300
301 WARN_ON_ONCE(!dev->coherent_dma_mask);
302
303 if (dma_alloc_from_dev_coherent(dev, size, dma_handle, &cpu_addr))
304 return cpu_addr;
305
306 /* let the implementation decide on the zone to allocate from: */
307 flag &= ~(__GFP_DMA | __GFP_DMA32 | __GFP_HIGHMEM);
308
309 if (dma_is_direct(ops))
310 cpu_addr = dma_direct_alloc(dev, size, dma_handle, flag, attrs);
311 else if (ops->alloc)
312 cpu_addr = ops->alloc(dev, size, dma_handle, flag, attrs);
313 else
314 return NULL;
315
316 debug_dma_alloc_coherent(dev, size, *dma_handle, cpu_addr);
317 return cpu_addr;
318}
319EXPORT_SYMBOL(dma_alloc_attrs);
320
321void dma_free_attrs(struct device *dev, size_t size, void *cpu_addr,
322 dma_addr_t dma_handle, unsigned long attrs)
323{
324 const struct dma_map_ops *ops = get_dma_ops(dev);
325
326 if (dma_release_from_dev_coherent(dev, get_order(size), cpu_addr))
327 return;
328 /*
329 * On non-coherent platforms which implement DMA-coherent buffers via
330 * non-cacheable remaps, ops->free() may call vunmap(). Thus getting
331 * this far in IRQ context is a) at risk of a BUG_ON() or trying to
332 * sleep on some machines, and b) an indication that the driver is
333 * probably misusing the coherent API anyway.
334 */
335 WARN_ON(irqs_disabled());
336
337 if (!cpu_addr)
338 return;
339
340 debug_dma_free_coherent(dev, size, cpu_addr, dma_handle);
341 if (dma_is_direct(ops))
342 dma_direct_free(dev, size, cpu_addr, dma_handle, attrs);
343 else if (ops->free)
344 ops->free(dev, size, cpu_addr, dma_handle, attrs);
345}
346EXPORT_SYMBOL(dma_free_attrs);
347
348int dma_supported(struct device *dev, u64 mask)
349{
350 const struct dma_map_ops *ops = get_dma_ops(dev);
351
352 if (dma_is_direct(ops))
353 return dma_direct_supported(dev, mask);
354 if (!ops->dma_supported)
355 return 1;
356 return ops->dma_supported(dev, mask);
357}
358EXPORT_SYMBOL(dma_supported);
359
360#ifdef CONFIG_ARCH_HAS_DMA_SET_MASK
361void arch_dma_set_mask(struct device *dev, u64 mask);
362#else
363#define arch_dma_set_mask(dev, mask) do { } while (0)
364#endif
365
366int dma_set_mask(struct device *dev, u64 mask)
367{
368 /*
369 * Truncate the mask to the actually supported dma_addr_t width to
370 * avoid generating unsupportable addresses.
371 */
372 mask = (dma_addr_t)mask;
373
374 if (!dev->dma_mask || !dma_supported(dev, mask))
375 return -EIO;
376
377 arch_dma_set_mask(dev, mask);
378 *dev->dma_mask = mask;
379 return 0;
380}
381EXPORT_SYMBOL(dma_set_mask);
382
383#ifndef CONFIG_ARCH_HAS_DMA_SET_COHERENT_MASK
384int dma_set_coherent_mask(struct device *dev, u64 mask)
385{
386 /*
387 * Truncate the mask to the actually supported dma_addr_t width to
388 * avoid generating unsupportable addresses.
389 */
390 mask = (dma_addr_t)mask;
391
392 if (!dma_supported(dev, mask))
393 return -EIO;
394
395 dev->coherent_dma_mask = mask;
396 return 0;
397}
398EXPORT_SYMBOL(dma_set_coherent_mask);
399#endif
400
401void dma_cache_sync(struct device *dev, void *vaddr, size_t size,
402 enum dma_data_direction dir)
403{
404 const struct dma_map_ops *ops = get_dma_ops(dev);
405
406 BUG_ON(!valid_dma_direction(dir));
407
408 if (dma_is_direct(ops))
409 arch_dma_cache_sync(dev, vaddr, size, dir);
410 else if (ops->cache_sync)
411 ops->cache_sync(dev, vaddr, size, dir);
412}
413EXPORT_SYMBOL(dma_cache_sync);
414
415size_t dma_max_mapping_size(struct device *dev)
416{
417 const struct dma_map_ops *ops = get_dma_ops(dev);
418 size_t size = SIZE_MAX;
419
420 if (dma_is_direct(ops))
421 size = dma_direct_max_mapping_size(dev);
422 else if (ops && ops->max_mapping_size)
423 size = ops->max_mapping_size(dev);
424
425 return size;
426}
427EXPORT_SYMBOL_GPL(dma_max_mapping_size);
428
429unsigned long dma_get_merge_boundary(struct device *dev)
430{
431 const struct dma_map_ops *ops = get_dma_ops(dev);
432
433 if (!ops || !ops->get_merge_boundary)
434 return 0; /* can't merge */
435
436 return ops->get_merge_boundary(dev);
437}
438EXPORT_SYMBOL_GPL(dma_get_merge_boundary);
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * arch-independent dma-mapping routines
4 *
5 * Copyright (c) 2006 SUSE Linux Products GmbH
6 * Copyright (c) 2006 Tejun Heo <teheo@suse.de>
7 */
8#include <linux/memblock.h> /* for max_pfn */
9#include <linux/acpi.h>
10#include <linux/dma-map-ops.h>
11#include <linux/export.h>
12#include <linux/gfp.h>
13#include <linux/of_device.h>
14#include <linux/slab.h>
15#include <linux/vmalloc.h>
16#include "debug.h"
17#include "direct.h"
18
19bool dma_default_coherent;
20
21/*
22 * Managed DMA API
23 */
24struct dma_devres {
25 size_t size;
26 void *vaddr;
27 dma_addr_t dma_handle;
28 unsigned long attrs;
29};
30
31static void dmam_release(struct device *dev, void *res)
32{
33 struct dma_devres *this = res;
34
35 dma_free_attrs(dev, this->size, this->vaddr, this->dma_handle,
36 this->attrs);
37}
38
39static int dmam_match(struct device *dev, void *res, void *match_data)
40{
41 struct dma_devres *this = res, *match = match_data;
42
43 if (this->vaddr == match->vaddr) {
44 WARN_ON(this->size != match->size ||
45 this->dma_handle != match->dma_handle);
46 return 1;
47 }
48 return 0;
49}
50
51/**
52 * dmam_free_coherent - Managed dma_free_coherent()
53 * @dev: Device to free coherent memory for
54 * @size: Size of allocation
55 * @vaddr: Virtual address of the memory to free
56 * @dma_handle: DMA handle of the memory to free
57 *
58 * Managed dma_free_coherent().
59 */
60void dmam_free_coherent(struct device *dev, size_t size, void *vaddr,
61 dma_addr_t dma_handle)
62{
63 struct dma_devres match_data = { size, vaddr, dma_handle };
64
65 dma_free_coherent(dev, size, vaddr, dma_handle);
66 WARN_ON(devres_destroy(dev, dmam_release, dmam_match, &match_data));
67}
68EXPORT_SYMBOL(dmam_free_coherent);
69
70/**
71 * dmam_alloc_attrs - Managed dma_alloc_attrs()
72 * @dev: Device to allocate non_coherent memory for
73 * @size: Size of allocation
74 * @dma_handle: Out argument for allocated DMA handle
75 * @gfp: Allocation flags
76 * @attrs: Flags in the DMA_ATTR_* namespace.
77 *
78 * Managed dma_alloc_attrs(). Memory allocated using this function will be
79 * automatically released on driver detach.
80 *
81 * RETURNS:
82 * Pointer to allocated memory on success, NULL on failure.
83 */
84void *dmam_alloc_attrs(struct device *dev, size_t size, dma_addr_t *dma_handle,
85 gfp_t gfp, unsigned long attrs)
86{
87 struct dma_devres *dr;
88 void *vaddr;
89
90 dr = devres_alloc(dmam_release, sizeof(*dr), gfp);
91 if (!dr)
92 return NULL;
93
94 vaddr = dma_alloc_attrs(dev, size, dma_handle, gfp, attrs);
95 if (!vaddr) {
96 devres_free(dr);
97 return NULL;
98 }
99
100 dr->vaddr = vaddr;
101 dr->dma_handle = *dma_handle;
102 dr->size = size;
103 dr->attrs = attrs;
104
105 devres_add(dev, dr);
106
107 return vaddr;
108}
109EXPORT_SYMBOL(dmam_alloc_attrs);
110
111static bool dma_go_direct(struct device *dev, dma_addr_t mask,
112 const struct dma_map_ops *ops)
113{
114 if (likely(!ops))
115 return true;
116#ifdef CONFIG_DMA_OPS_BYPASS
117 if (dev->dma_ops_bypass)
118 return min_not_zero(mask, dev->bus_dma_limit) >=
119 dma_direct_get_required_mask(dev);
120#endif
121 return false;
122}
123
124
125/*
126 * Check if the devices uses a direct mapping for streaming DMA operations.
127 * This allows IOMMU drivers to set a bypass mode if the DMA mask is large
128 * enough.
129 */
130static inline bool dma_alloc_direct(struct device *dev,
131 const struct dma_map_ops *ops)
132{
133 return dma_go_direct(dev, dev->coherent_dma_mask, ops);
134}
135
136static inline bool dma_map_direct(struct device *dev,
137 const struct dma_map_ops *ops)
138{
139 return dma_go_direct(dev, *dev->dma_mask, ops);
140}
141
142dma_addr_t dma_map_page_attrs(struct device *dev, struct page *page,
143 size_t offset, size_t size, enum dma_data_direction dir,
144 unsigned long attrs)
145{
146 const struct dma_map_ops *ops = get_dma_ops(dev);
147 dma_addr_t addr;
148
149 BUG_ON(!valid_dma_direction(dir));
150
151 if (WARN_ON_ONCE(!dev->dma_mask))
152 return DMA_MAPPING_ERROR;
153
154 if (dma_map_direct(dev, ops) ||
155 arch_dma_map_page_direct(dev, page_to_phys(page) + offset + size))
156 addr = dma_direct_map_page(dev, page, offset, size, dir, attrs);
157 else
158 addr = ops->map_page(dev, page, offset, size, dir, attrs);
159 debug_dma_map_page(dev, page, offset, size, dir, addr);
160
161 return addr;
162}
163EXPORT_SYMBOL(dma_map_page_attrs);
164
165void dma_unmap_page_attrs(struct device *dev, dma_addr_t addr, size_t size,
166 enum dma_data_direction dir, unsigned long attrs)
167{
168 const struct dma_map_ops *ops = get_dma_ops(dev);
169
170 BUG_ON(!valid_dma_direction(dir));
171 if (dma_map_direct(dev, ops) ||
172 arch_dma_unmap_page_direct(dev, addr + size))
173 dma_direct_unmap_page(dev, addr, size, dir, attrs);
174 else if (ops->unmap_page)
175 ops->unmap_page(dev, addr, size, dir, attrs);
176 debug_dma_unmap_page(dev, addr, size, dir);
177}
178EXPORT_SYMBOL(dma_unmap_page_attrs);
179
180/*
181 * dma_maps_sg_attrs returns 0 on error and > 0 on success.
182 * It should never return a value < 0.
183 */
184int dma_map_sg_attrs(struct device *dev, struct scatterlist *sg, int nents,
185 enum dma_data_direction dir, unsigned long attrs)
186{
187 const struct dma_map_ops *ops = get_dma_ops(dev);
188 int ents;
189
190 BUG_ON(!valid_dma_direction(dir));
191
192 if (WARN_ON_ONCE(!dev->dma_mask))
193 return 0;
194
195 if (dma_map_direct(dev, ops) ||
196 arch_dma_map_sg_direct(dev, sg, nents))
197 ents = dma_direct_map_sg(dev, sg, nents, dir, attrs);
198 else
199 ents = ops->map_sg(dev, sg, nents, dir, attrs);
200 BUG_ON(ents < 0);
201 debug_dma_map_sg(dev, sg, nents, ents, dir);
202
203 return ents;
204}
205EXPORT_SYMBOL(dma_map_sg_attrs);
206
207void dma_unmap_sg_attrs(struct device *dev, struct scatterlist *sg,
208 int nents, enum dma_data_direction dir,
209 unsigned long attrs)
210{
211 const struct dma_map_ops *ops = get_dma_ops(dev);
212
213 BUG_ON(!valid_dma_direction(dir));
214 debug_dma_unmap_sg(dev, sg, nents, dir);
215 if (dma_map_direct(dev, ops) ||
216 arch_dma_unmap_sg_direct(dev, sg, nents))
217 dma_direct_unmap_sg(dev, sg, nents, dir, attrs);
218 else if (ops->unmap_sg)
219 ops->unmap_sg(dev, sg, nents, dir, attrs);
220}
221EXPORT_SYMBOL(dma_unmap_sg_attrs);
222
223dma_addr_t dma_map_resource(struct device *dev, phys_addr_t phys_addr,
224 size_t size, enum dma_data_direction dir, unsigned long attrs)
225{
226 const struct dma_map_ops *ops = get_dma_ops(dev);
227 dma_addr_t addr = DMA_MAPPING_ERROR;
228
229 BUG_ON(!valid_dma_direction(dir));
230
231 if (WARN_ON_ONCE(!dev->dma_mask))
232 return DMA_MAPPING_ERROR;
233
234 /* Don't allow RAM to be mapped */
235 if (WARN_ON_ONCE(pfn_valid(PHYS_PFN(phys_addr))))
236 return DMA_MAPPING_ERROR;
237
238 if (dma_map_direct(dev, ops))
239 addr = dma_direct_map_resource(dev, phys_addr, size, dir, attrs);
240 else if (ops->map_resource)
241 addr = ops->map_resource(dev, phys_addr, size, dir, attrs);
242
243 debug_dma_map_resource(dev, phys_addr, size, dir, addr);
244 return addr;
245}
246EXPORT_SYMBOL(dma_map_resource);
247
248void dma_unmap_resource(struct device *dev, dma_addr_t addr, size_t size,
249 enum dma_data_direction dir, unsigned long attrs)
250{
251 const struct dma_map_ops *ops = get_dma_ops(dev);
252
253 BUG_ON(!valid_dma_direction(dir));
254 if (!dma_map_direct(dev, ops) && ops->unmap_resource)
255 ops->unmap_resource(dev, addr, size, dir, attrs);
256 debug_dma_unmap_resource(dev, addr, size, dir);
257}
258EXPORT_SYMBOL(dma_unmap_resource);
259
260void dma_sync_single_for_cpu(struct device *dev, dma_addr_t addr, size_t size,
261 enum dma_data_direction dir)
262{
263 const struct dma_map_ops *ops = get_dma_ops(dev);
264
265 BUG_ON(!valid_dma_direction(dir));
266 if (dma_map_direct(dev, ops))
267 dma_direct_sync_single_for_cpu(dev, addr, size, dir);
268 else if (ops->sync_single_for_cpu)
269 ops->sync_single_for_cpu(dev, addr, size, dir);
270 debug_dma_sync_single_for_cpu(dev, addr, size, dir);
271}
272EXPORT_SYMBOL(dma_sync_single_for_cpu);
273
274void dma_sync_single_for_device(struct device *dev, dma_addr_t addr,
275 size_t size, enum dma_data_direction dir)
276{
277 const struct dma_map_ops *ops = get_dma_ops(dev);
278
279 BUG_ON(!valid_dma_direction(dir));
280 if (dma_map_direct(dev, ops))
281 dma_direct_sync_single_for_device(dev, addr, size, dir);
282 else if (ops->sync_single_for_device)
283 ops->sync_single_for_device(dev, addr, size, dir);
284 debug_dma_sync_single_for_device(dev, addr, size, dir);
285}
286EXPORT_SYMBOL(dma_sync_single_for_device);
287
288void dma_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg,
289 int nelems, enum dma_data_direction dir)
290{
291 const struct dma_map_ops *ops = get_dma_ops(dev);
292
293 BUG_ON(!valid_dma_direction(dir));
294 if (dma_map_direct(dev, ops))
295 dma_direct_sync_sg_for_cpu(dev, sg, nelems, dir);
296 else if (ops->sync_sg_for_cpu)
297 ops->sync_sg_for_cpu(dev, sg, nelems, dir);
298 debug_dma_sync_sg_for_cpu(dev, sg, nelems, dir);
299}
300EXPORT_SYMBOL(dma_sync_sg_for_cpu);
301
302void dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg,
303 int nelems, enum dma_data_direction dir)
304{
305 const struct dma_map_ops *ops = get_dma_ops(dev);
306
307 BUG_ON(!valid_dma_direction(dir));
308 if (dma_map_direct(dev, ops))
309 dma_direct_sync_sg_for_device(dev, sg, nelems, dir);
310 else if (ops->sync_sg_for_device)
311 ops->sync_sg_for_device(dev, sg, nelems, dir);
312 debug_dma_sync_sg_for_device(dev, sg, nelems, dir);
313}
314EXPORT_SYMBOL(dma_sync_sg_for_device);
315
316/*
317 * The whole dma_get_sgtable() idea is fundamentally unsafe - it seems
318 * that the intention is to allow exporting memory allocated via the
319 * coherent DMA APIs through the dma_buf API, which only accepts a
320 * scattertable. This presents a couple of problems:
321 * 1. Not all memory allocated via the coherent DMA APIs is backed by
322 * a struct page
323 * 2. Passing coherent DMA memory into the streaming APIs is not allowed
324 * as we will try to flush the memory through a different alias to that
325 * actually being used (and the flushes are redundant.)
326 */
327int dma_get_sgtable_attrs(struct device *dev, struct sg_table *sgt,
328 void *cpu_addr, dma_addr_t dma_addr, size_t size,
329 unsigned long attrs)
330{
331 const struct dma_map_ops *ops = get_dma_ops(dev);
332
333 if (dma_alloc_direct(dev, ops))
334 return dma_direct_get_sgtable(dev, sgt, cpu_addr, dma_addr,
335 size, attrs);
336 if (!ops->get_sgtable)
337 return -ENXIO;
338 return ops->get_sgtable(dev, sgt, cpu_addr, dma_addr, size, attrs);
339}
340EXPORT_SYMBOL(dma_get_sgtable_attrs);
341
342#ifdef CONFIG_MMU
343/*
344 * Return the page attributes used for mapping dma_alloc_* memory, either in
345 * kernel space if remapping is needed, or to userspace through dma_mmap_*.
346 */
347pgprot_t dma_pgprot(struct device *dev, pgprot_t prot, unsigned long attrs)
348{
349 if (force_dma_unencrypted(dev))
350 prot = pgprot_decrypted(prot);
351 if (dev_is_dma_coherent(dev))
352 return prot;
353#ifdef CONFIG_ARCH_HAS_DMA_WRITE_COMBINE
354 if (attrs & DMA_ATTR_WRITE_COMBINE)
355 return pgprot_writecombine(prot);
356#endif
357 return pgprot_dmacoherent(prot);
358}
359#endif /* CONFIG_MMU */
360
361/**
362 * dma_can_mmap - check if a given device supports dma_mmap_*
363 * @dev: device to check
364 *
365 * Returns %true if @dev supports dma_mmap_coherent() and dma_mmap_attrs() to
366 * map DMA allocations to userspace.
367 */
368bool dma_can_mmap(struct device *dev)
369{
370 const struct dma_map_ops *ops = get_dma_ops(dev);
371
372 if (dma_alloc_direct(dev, ops))
373 return dma_direct_can_mmap(dev);
374 return ops->mmap != NULL;
375}
376EXPORT_SYMBOL_GPL(dma_can_mmap);
377
378/**
379 * dma_mmap_attrs - map a coherent DMA allocation into user space
380 * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
381 * @vma: vm_area_struct describing requested user mapping
382 * @cpu_addr: kernel CPU-view address returned from dma_alloc_attrs
383 * @dma_addr: device-view address returned from dma_alloc_attrs
384 * @size: size of memory originally requested in dma_alloc_attrs
385 * @attrs: attributes of mapping properties requested in dma_alloc_attrs
386 *
387 * Map a coherent DMA buffer previously allocated by dma_alloc_attrs into user
388 * space. The coherent DMA buffer must not be freed by the driver until the
389 * user space mapping has been released.
390 */
391int dma_mmap_attrs(struct device *dev, struct vm_area_struct *vma,
392 void *cpu_addr, dma_addr_t dma_addr, size_t size,
393 unsigned long attrs)
394{
395 const struct dma_map_ops *ops = get_dma_ops(dev);
396
397 if (dma_alloc_direct(dev, ops))
398 return dma_direct_mmap(dev, vma, cpu_addr, dma_addr, size,
399 attrs);
400 if (!ops->mmap)
401 return -ENXIO;
402 return ops->mmap(dev, vma, cpu_addr, dma_addr, size, attrs);
403}
404EXPORT_SYMBOL(dma_mmap_attrs);
405
406u64 dma_get_required_mask(struct device *dev)
407{
408 const struct dma_map_ops *ops = get_dma_ops(dev);
409
410 if (dma_alloc_direct(dev, ops))
411 return dma_direct_get_required_mask(dev);
412 if (ops->get_required_mask)
413 return ops->get_required_mask(dev);
414
415 /*
416 * We require every DMA ops implementation to at least support a 32-bit
417 * DMA mask (and use bounce buffering if that isn't supported in
418 * hardware). As the direct mapping code has its own routine to
419 * actually report an optimal mask we default to 32-bit here as that
420 * is the right thing for most IOMMUs, and at least not actively
421 * harmful in general.
422 */
423 return DMA_BIT_MASK(32);
424}
425EXPORT_SYMBOL_GPL(dma_get_required_mask);
426
427void *dma_alloc_attrs(struct device *dev, size_t size, dma_addr_t *dma_handle,
428 gfp_t flag, unsigned long attrs)
429{
430 const struct dma_map_ops *ops = get_dma_ops(dev);
431 void *cpu_addr;
432
433 WARN_ON_ONCE(!dev->coherent_dma_mask);
434
435 if (dma_alloc_from_dev_coherent(dev, size, dma_handle, &cpu_addr))
436 return cpu_addr;
437
438 /* let the implementation decide on the zone to allocate from: */
439 flag &= ~(__GFP_DMA | __GFP_DMA32 | __GFP_HIGHMEM);
440
441 if (dma_alloc_direct(dev, ops))
442 cpu_addr = dma_direct_alloc(dev, size, dma_handle, flag, attrs);
443 else if (ops->alloc)
444 cpu_addr = ops->alloc(dev, size, dma_handle, flag, attrs);
445 else
446 return NULL;
447
448 debug_dma_alloc_coherent(dev, size, *dma_handle, cpu_addr);
449 return cpu_addr;
450}
451EXPORT_SYMBOL(dma_alloc_attrs);
452
453void dma_free_attrs(struct device *dev, size_t size, void *cpu_addr,
454 dma_addr_t dma_handle, unsigned long attrs)
455{
456 const struct dma_map_ops *ops = get_dma_ops(dev);
457
458 if (dma_release_from_dev_coherent(dev, get_order(size), cpu_addr))
459 return;
460 /*
461 * On non-coherent platforms which implement DMA-coherent buffers via
462 * non-cacheable remaps, ops->free() may call vunmap(). Thus getting
463 * this far in IRQ context is a) at risk of a BUG_ON() or trying to
464 * sleep on some machines, and b) an indication that the driver is
465 * probably misusing the coherent API anyway.
466 */
467 WARN_ON(irqs_disabled());
468
469 if (!cpu_addr)
470 return;
471
472 debug_dma_free_coherent(dev, size, cpu_addr, dma_handle);
473 if (dma_alloc_direct(dev, ops))
474 dma_direct_free(dev, size, cpu_addr, dma_handle, attrs);
475 else if (ops->free)
476 ops->free(dev, size, cpu_addr, dma_handle, attrs);
477}
478EXPORT_SYMBOL(dma_free_attrs);
479
480static struct page *__dma_alloc_pages(struct device *dev, size_t size,
481 dma_addr_t *dma_handle, enum dma_data_direction dir, gfp_t gfp)
482{
483 const struct dma_map_ops *ops = get_dma_ops(dev);
484
485 if (WARN_ON_ONCE(!dev->coherent_dma_mask))
486 return NULL;
487 if (WARN_ON_ONCE(gfp & (__GFP_DMA | __GFP_DMA32 | __GFP_HIGHMEM)))
488 return NULL;
489
490 size = PAGE_ALIGN(size);
491 if (dma_alloc_direct(dev, ops))
492 return dma_direct_alloc_pages(dev, size, dma_handle, dir, gfp);
493 if (!ops->alloc_pages)
494 return NULL;
495 return ops->alloc_pages(dev, size, dma_handle, dir, gfp);
496}
497
498struct page *dma_alloc_pages(struct device *dev, size_t size,
499 dma_addr_t *dma_handle, enum dma_data_direction dir, gfp_t gfp)
500{
501 struct page *page = __dma_alloc_pages(dev, size, dma_handle, dir, gfp);
502
503 if (page)
504 debug_dma_map_page(dev, page, 0, size, dir, *dma_handle);
505 return page;
506}
507EXPORT_SYMBOL_GPL(dma_alloc_pages);
508
509static void __dma_free_pages(struct device *dev, size_t size, struct page *page,
510 dma_addr_t dma_handle, enum dma_data_direction dir)
511{
512 const struct dma_map_ops *ops = get_dma_ops(dev);
513
514 size = PAGE_ALIGN(size);
515 if (dma_alloc_direct(dev, ops))
516 dma_direct_free_pages(dev, size, page, dma_handle, dir);
517 else if (ops->free_pages)
518 ops->free_pages(dev, size, page, dma_handle, dir);
519}
520
521void dma_free_pages(struct device *dev, size_t size, struct page *page,
522 dma_addr_t dma_handle, enum dma_data_direction dir)
523{
524 debug_dma_unmap_page(dev, dma_handle, size, dir);
525 __dma_free_pages(dev, size, page, dma_handle, dir);
526}
527EXPORT_SYMBOL_GPL(dma_free_pages);
528
529int dma_mmap_pages(struct device *dev, struct vm_area_struct *vma,
530 size_t size, struct page *page)
531{
532 unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT;
533
534 if (vma->vm_pgoff >= count || vma_pages(vma) > count - vma->vm_pgoff)
535 return -ENXIO;
536 return remap_pfn_range(vma, vma->vm_start,
537 page_to_pfn(page) + vma->vm_pgoff,
538 vma_pages(vma) << PAGE_SHIFT, vma->vm_page_prot);
539}
540EXPORT_SYMBOL_GPL(dma_mmap_pages);
541
542static struct sg_table *alloc_single_sgt(struct device *dev, size_t size,
543 enum dma_data_direction dir, gfp_t gfp)
544{
545 struct sg_table *sgt;
546 struct page *page;
547
548 sgt = kmalloc(sizeof(*sgt), gfp);
549 if (!sgt)
550 return NULL;
551 if (sg_alloc_table(sgt, 1, gfp))
552 goto out_free_sgt;
553 page = __dma_alloc_pages(dev, size, &sgt->sgl->dma_address, dir, gfp);
554 if (!page)
555 goto out_free_table;
556 sg_set_page(sgt->sgl, page, PAGE_ALIGN(size), 0);
557 sg_dma_len(sgt->sgl) = sgt->sgl->length;
558 return sgt;
559out_free_table:
560 sg_free_table(sgt);
561out_free_sgt:
562 kfree(sgt);
563 return NULL;
564}
565
566struct sg_table *dma_alloc_noncontiguous(struct device *dev, size_t size,
567 enum dma_data_direction dir, gfp_t gfp, unsigned long attrs)
568{
569 const struct dma_map_ops *ops = get_dma_ops(dev);
570 struct sg_table *sgt;
571
572 if (WARN_ON_ONCE(attrs & ~DMA_ATTR_ALLOC_SINGLE_PAGES))
573 return NULL;
574
575 if (ops && ops->alloc_noncontiguous)
576 sgt = ops->alloc_noncontiguous(dev, size, dir, gfp, attrs);
577 else
578 sgt = alloc_single_sgt(dev, size, dir, gfp);
579
580 if (sgt) {
581 sgt->nents = 1;
582 debug_dma_map_sg(dev, sgt->sgl, sgt->orig_nents, 1, dir);
583 }
584 return sgt;
585}
586EXPORT_SYMBOL_GPL(dma_alloc_noncontiguous);
587
588static void free_single_sgt(struct device *dev, size_t size,
589 struct sg_table *sgt, enum dma_data_direction dir)
590{
591 __dma_free_pages(dev, size, sg_page(sgt->sgl), sgt->sgl->dma_address,
592 dir);
593 sg_free_table(sgt);
594 kfree(sgt);
595}
596
597void dma_free_noncontiguous(struct device *dev, size_t size,
598 struct sg_table *sgt, enum dma_data_direction dir)
599{
600 const struct dma_map_ops *ops = get_dma_ops(dev);
601
602 debug_dma_unmap_sg(dev, sgt->sgl, sgt->orig_nents, dir);
603 if (ops && ops->free_noncontiguous)
604 ops->free_noncontiguous(dev, size, sgt, dir);
605 else
606 free_single_sgt(dev, size, sgt, dir);
607}
608EXPORT_SYMBOL_GPL(dma_free_noncontiguous);
609
610void *dma_vmap_noncontiguous(struct device *dev, size_t size,
611 struct sg_table *sgt)
612{
613 const struct dma_map_ops *ops = get_dma_ops(dev);
614 unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT;
615
616 if (ops && ops->alloc_noncontiguous)
617 return vmap(sgt_handle(sgt)->pages, count, VM_MAP, PAGE_KERNEL);
618 return page_address(sg_page(sgt->sgl));
619}
620EXPORT_SYMBOL_GPL(dma_vmap_noncontiguous);
621
622void dma_vunmap_noncontiguous(struct device *dev, void *vaddr)
623{
624 const struct dma_map_ops *ops = get_dma_ops(dev);
625
626 if (ops && ops->alloc_noncontiguous)
627 vunmap(vaddr);
628}
629EXPORT_SYMBOL_GPL(dma_vunmap_noncontiguous);
630
631int dma_mmap_noncontiguous(struct device *dev, struct vm_area_struct *vma,
632 size_t size, struct sg_table *sgt)
633{
634 const struct dma_map_ops *ops = get_dma_ops(dev);
635
636 if (ops && ops->alloc_noncontiguous) {
637 unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT;
638
639 if (vma->vm_pgoff >= count ||
640 vma_pages(vma) > count - vma->vm_pgoff)
641 return -ENXIO;
642 return vm_map_pages(vma, sgt_handle(sgt)->pages, count);
643 }
644 return dma_mmap_pages(dev, vma, size, sg_page(sgt->sgl));
645}
646EXPORT_SYMBOL_GPL(dma_mmap_noncontiguous);
647
648int dma_supported(struct device *dev, u64 mask)
649{
650 const struct dma_map_ops *ops = get_dma_ops(dev);
651
652 /*
653 * ->dma_supported sets the bypass flag, so we must always call
654 * into the method here unless the device is truly direct mapped.
655 */
656 if (!ops)
657 return dma_direct_supported(dev, mask);
658 if (!ops->dma_supported)
659 return 1;
660 return ops->dma_supported(dev, mask);
661}
662EXPORT_SYMBOL(dma_supported);
663
664#ifdef CONFIG_ARCH_HAS_DMA_SET_MASK
665void arch_dma_set_mask(struct device *dev, u64 mask);
666#else
667#define arch_dma_set_mask(dev, mask) do { } while (0)
668#endif
669
670int dma_set_mask(struct device *dev, u64 mask)
671{
672 /*
673 * Truncate the mask to the actually supported dma_addr_t width to
674 * avoid generating unsupportable addresses.
675 */
676 mask = (dma_addr_t)mask;
677
678 if (!dev->dma_mask || !dma_supported(dev, mask))
679 return -EIO;
680
681 arch_dma_set_mask(dev, mask);
682 *dev->dma_mask = mask;
683 return 0;
684}
685EXPORT_SYMBOL(dma_set_mask);
686
687#ifndef CONFIG_ARCH_HAS_DMA_SET_COHERENT_MASK
688int dma_set_coherent_mask(struct device *dev, u64 mask)
689{
690 /*
691 * Truncate the mask to the actually supported dma_addr_t width to
692 * avoid generating unsupportable addresses.
693 */
694 mask = (dma_addr_t)mask;
695
696 if (!dma_supported(dev, mask))
697 return -EIO;
698
699 dev->coherent_dma_mask = mask;
700 return 0;
701}
702EXPORT_SYMBOL(dma_set_coherent_mask);
703#endif
704
705size_t dma_max_mapping_size(struct device *dev)
706{
707 const struct dma_map_ops *ops = get_dma_ops(dev);
708 size_t size = SIZE_MAX;
709
710 if (dma_map_direct(dev, ops))
711 size = dma_direct_max_mapping_size(dev);
712 else if (ops && ops->max_mapping_size)
713 size = ops->max_mapping_size(dev);
714
715 return size;
716}
717EXPORT_SYMBOL_GPL(dma_max_mapping_size);
718
719bool dma_need_sync(struct device *dev, dma_addr_t dma_addr)
720{
721 const struct dma_map_ops *ops = get_dma_ops(dev);
722
723 if (dma_map_direct(dev, ops))
724 return dma_direct_need_sync(dev, dma_addr);
725 return ops->sync_single_for_cpu || ops->sync_single_for_device;
726}
727EXPORT_SYMBOL_GPL(dma_need_sync);
728
729unsigned long dma_get_merge_boundary(struct device *dev)
730{
731 const struct dma_map_ops *ops = get_dma_ops(dev);
732
733 if (!ops || !ops->get_merge_boundary)
734 return 0; /* can't merge */
735
736 return ops->get_merge_boundary(dev);
737}
738EXPORT_SYMBOL_GPL(dma_get_merge_boundary);