xref: /linux/kernel/dma/mapping.c (revision d6e4b3e326d8b44675b9e19534347d97073826aa)
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  */
21 struct dma_devres {
22 	size_t		size;
23 	void		*vaddr;
24 	dma_addr_t	dma_handle;
25 	unsigned long	attrs;
26 };
27 
28 static 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 
36 static 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_alloc_coherent - Managed dma_alloc_coherent()
50  * @dev: Device to allocate coherent memory for
51  * @size: Size of allocation
52  * @dma_handle: Out argument for allocated DMA handle
53  * @gfp: Allocation flags
54  *
55  * Managed dma_alloc_coherent().  Memory allocated using this function
56  * will be automatically released on driver detach.
57  *
58  * RETURNS:
59  * Pointer to allocated memory on success, NULL on failure.
60  */
61 void *dmam_alloc_coherent(struct device *dev, size_t size,
62 			   dma_addr_t *dma_handle, gfp_t gfp)
63 {
64 	struct dma_devres *dr;
65 	void *vaddr;
66 
67 	dr = devres_alloc(dmam_release, sizeof(*dr), gfp);
68 	if (!dr)
69 		return NULL;
70 
71 	vaddr = dma_alloc_coherent(dev, size, dma_handle, gfp);
72 	if (!vaddr) {
73 		devres_free(dr);
74 		return NULL;
75 	}
76 
77 	dr->vaddr = vaddr;
78 	dr->dma_handle = *dma_handle;
79 	dr->size = size;
80 
81 	devres_add(dev, dr);
82 
83 	return vaddr;
84 }
85 EXPORT_SYMBOL(dmam_alloc_coherent);
86 
87 /**
88  * dmam_free_coherent - Managed dma_free_coherent()
89  * @dev: Device to free coherent memory for
90  * @size: Size of allocation
91  * @vaddr: Virtual address of the memory to free
92  * @dma_handle: DMA handle of the memory to free
93  *
94  * Managed dma_free_coherent().
95  */
96 void dmam_free_coherent(struct device *dev, size_t size, void *vaddr,
97 			dma_addr_t dma_handle)
98 {
99 	struct dma_devres match_data = { size, vaddr, dma_handle };
100 
101 	dma_free_coherent(dev, size, vaddr, dma_handle);
102 	WARN_ON(devres_destroy(dev, dmam_release, dmam_match, &match_data));
103 }
104 EXPORT_SYMBOL(dmam_free_coherent);
105 
106 /**
107  * dmam_alloc_attrs - Managed dma_alloc_attrs()
108  * @dev: Device to allocate non_coherent memory for
109  * @size: Size of allocation
110  * @dma_handle: Out argument for allocated DMA handle
111  * @gfp: Allocation flags
112  * @attrs: Flags in the DMA_ATTR_* namespace.
113  *
114  * Managed dma_alloc_attrs().  Memory allocated using this function will be
115  * automatically released on driver detach.
116  *
117  * RETURNS:
118  * Pointer to allocated memory on success, NULL on failure.
119  */
120 void *dmam_alloc_attrs(struct device *dev, size_t size, dma_addr_t *dma_handle,
121 		gfp_t gfp, unsigned long attrs)
122 {
123 	struct dma_devres *dr;
124 	void *vaddr;
125 
126 	dr = devres_alloc(dmam_release, sizeof(*dr), gfp);
127 	if (!dr)
128 		return NULL;
129 
130 	vaddr = dma_alloc_attrs(dev, size, dma_handle, gfp, attrs);
131 	if (!vaddr) {
132 		devres_free(dr);
133 		return NULL;
134 	}
135 
136 	dr->vaddr = vaddr;
137 	dr->dma_handle = *dma_handle;
138 	dr->size = size;
139 	dr->attrs = attrs;
140 
141 	devres_add(dev, dr);
142 
143 	return vaddr;
144 }
145 EXPORT_SYMBOL(dmam_alloc_attrs);
146 
147 #ifdef CONFIG_HAVE_GENERIC_DMA_COHERENT
148 
149 static void dmam_coherent_decl_release(struct device *dev, void *res)
150 {
151 	dma_release_declared_memory(dev);
152 }
153 
154 /**
155  * dmam_declare_coherent_memory - Managed dma_declare_coherent_memory()
156  * @dev: Device to declare coherent memory for
157  * @phys_addr: Physical address of coherent memory to be declared
158  * @device_addr: Device address of coherent memory to be declared
159  * @size: Size of coherent memory to be declared
160  * @flags: Flags
161  *
162  * Managed dma_declare_coherent_memory().
163  *
164  * RETURNS:
165  * 0 on success, -errno on failure.
166  */
167 int dmam_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr,
168 				 dma_addr_t device_addr, size_t size, int flags)
169 {
170 	void *res;
171 	int rc;
172 
173 	res = devres_alloc(dmam_coherent_decl_release, 0, GFP_KERNEL);
174 	if (!res)
175 		return -ENOMEM;
176 
177 	rc = dma_declare_coherent_memory(dev, phys_addr, device_addr, size,
178 					 flags);
179 	if (!rc)
180 		devres_add(dev, res);
181 	else
182 		devres_free(res);
183 
184 	return rc;
185 }
186 EXPORT_SYMBOL(dmam_declare_coherent_memory);
187 
188 /**
189  * dmam_release_declared_memory - Managed dma_release_declared_memory().
190  * @dev: Device to release declared coherent memory for
191  *
192  * Managed dmam_release_declared_memory().
193  */
194 void dmam_release_declared_memory(struct device *dev)
195 {
196 	WARN_ON(devres_destroy(dev, dmam_coherent_decl_release, NULL, NULL));
197 }
198 EXPORT_SYMBOL(dmam_release_declared_memory);
199 
200 #endif
201 
202 /*
203  * Create scatter-list for the already allocated DMA buffer.
204  */
205 int dma_common_get_sgtable(struct device *dev, struct sg_table *sgt,
206 		 void *cpu_addr, dma_addr_t dma_addr, size_t size,
207 		 unsigned long attrs)
208 {
209 	struct page *page;
210 	int ret;
211 
212 	if (!dev_is_dma_coherent(dev)) {
213 		if (!IS_ENABLED(CONFIG_ARCH_HAS_DMA_COHERENT_TO_PFN))
214 			return -ENXIO;
215 
216 		page = pfn_to_page(arch_dma_coherent_to_pfn(dev, cpu_addr,
217 				dma_addr));
218 	} else {
219 		page = virt_to_page(cpu_addr);
220 	}
221 
222 	ret = sg_alloc_table(sgt, 1, GFP_KERNEL);
223 	if (!ret)
224 		sg_set_page(sgt->sgl, page, PAGE_ALIGN(size), 0);
225 	return ret;
226 }
227 
228 int dma_get_sgtable_attrs(struct device *dev, struct sg_table *sgt,
229 		void *cpu_addr, dma_addr_t dma_addr, size_t size,
230 		unsigned long attrs)
231 {
232 	const struct dma_map_ops *ops = get_dma_ops(dev);
233 
234 	if (!dma_is_direct(ops) && ops->get_sgtable)
235 		return ops->get_sgtable(dev, sgt, cpu_addr, dma_addr, size,
236 					attrs);
237 	return dma_common_get_sgtable(dev, sgt, cpu_addr, dma_addr, size,
238 			attrs);
239 }
240 EXPORT_SYMBOL(dma_get_sgtable_attrs);
241 
242 /*
243  * Create userspace mapping for the DMA-coherent memory.
244  */
245 int dma_common_mmap(struct device *dev, struct vm_area_struct *vma,
246 		void *cpu_addr, dma_addr_t dma_addr, size_t size,
247 		unsigned long attrs)
248 {
249 #ifndef CONFIG_ARCH_NO_COHERENT_DMA_MMAP
250 	unsigned long user_count = vma_pages(vma);
251 	unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT;
252 	unsigned long off = vma->vm_pgoff;
253 	unsigned long pfn;
254 	int ret = -ENXIO;
255 
256 	vma->vm_page_prot = arch_dma_mmap_pgprot(dev, vma->vm_page_prot, attrs);
257 
258 	if (dma_mmap_from_dev_coherent(dev, vma, cpu_addr, size, &ret))
259 		return ret;
260 
261 	if (off >= count || user_count > count - off)
262 		return -ENXIO;
263 
264 	if (!dev_is_dma_coherent(dev)) {
265 		if (!IS_ENABLED(CONFIG_ARCH_HAS_DMA_COHERENT_TO_PFN))
266 			return -ENXIO;
267 		pfn = arch_dma_coherent_to_pfn(dev, cpu_addr, dma_addr);
268 	} else {
269 		pfn = page_to_pfn(virt_to_page(cpu_addr));
270 	}
271 
272 	return remap_pfn_range(vma, vma->vm_start, pfn + vma->vm_pgoff,
273 			user_count << PAGE_SHIFT, vma->vm_page_prot);
274 #else
275 	return -ENXIO;
276 #endif /* !CONFIG_ARCH_NO_COHERENT_DMA_MMAP */
277 }
278 
279 /**
280  * dma_mmap_attrs - map a coherent DMA allocation into user space
281  * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices
282  * @vma: vm_area_struct describing requested user mapping
283  * @cpu_addr: kernel CPU-view address returned from dma_alloc_attrs
284  * @dma_addr: device-view address returned from dma_alloc_attrs
285  * @size: size of memory originally requested in dma_alloc_attrs
286  * @attrs: attributes of mapping properties requested in dma_alloc_attrs
287  *
288  * Map a coherent DMA buffer previously allocated by dma_alloc_attrs into user
289  * space.  The coherent DMA buffer must not be freed by the driver until the
290  * user space mapping has been released.
291  */
292 int dma_mmap_attrs(struct device *dev, struct vm_area_struct *vma,
293 		void *cpu_addr, dma_addr_t dma_addr, size_t size,
294 		unsigned long attrs)
295 {
296 	const struct dma_map_ops *ops = get_dma_ops(dev);
297 
298 	if (!dma_is_direct(ops) && ops->mmap)
299 		return ops->mmap(dev, vma, cpu_addr, dma_addr, size, attrs);
300 	return dma_common_mmap(dev, vma, cpu_addr, dma_addr, size, attrs);
301 }
302 EXPORT_SYMBOL(dma_mmap_attrs);
303 
304 #ifndef ARCH_HAS_DMA_GET_REQUIRED_MASK
305 static u64 dma_default_get_required_mask(struct device *dev)
306 {
307 	u32 low_totalram = ((max_pfn - 1) << PAGE_SHIFT);
308 	u32 high_totalram = ((max_pfn - 1) >> (32 - PAGE_SHIFT));
309 	u64 mask;
310 
311 	if (!high_totalram) {
312 		/* convert to mask just covering totalram */
313 		low_totalram = (1 << (fls(low_totalram) - 1));
314 		low_totalram += low_totalram - 1;
315 		mask = low_totalram;
316 	} else {
317 		high_totalram = (1 << (fls(high_totalram) - 1));
318 		high_totalram += high_totalram - 1;
319 		mask = (((u64)high_totalram) << 32) + 0xffffffff;
320 	}
321 	return mask;
322 }
323 
324 u64 dma_get_required_mask(struct device *dev)
325 {
326 	const struct dma_map_ops *ops = get_dma_ops(dev);
327 
328 	if (dma_is_direct(ops))
329 		return dma_direct_get_required_mask(dev);
330 	if (ops->get_required_mask)
331 		return ops->get_required_mask(dev);
332 	return dma_default_get_required_mask(dev);
333 }
334 EXPORT_SYMBOL_GPL(dma_get_required_mask);
335 #endif
336 
337 #ifndef arch_dma_alloc_attrs
338 #define arch_dma_alloc_attrs(dev)	(true)
339 #endif
340 
341 void *dma_alloc_attrs(struct device *dev, size_t size, dma_addr_t *dma_handle,
342 		gfp_t flag, unsigned long attrs)
343 {
344 	const struct dma_map_ops *ops = get_dma_ops(dev);
345 	void *cpu_addr;
346 
347 	WARN_ON_ONCE(dev && !dev->coherent_dma_mask);
348 
349 	if (dma_alloc_from_dev_coherent(dev, size, dma_handle, &cpu_addr))
350 		return cpu_addr;
351 
352 	/* let the implementation decide on the zone to allocate from: */
353 	flag &= ~(__GFP_DMA | __GFP_DMA32 | __GFP_HIGHMEM);
354 
355 	if (!arch_dma_alloc_attrs(&dev))
356 		return NULL;
357 
358 	if (dma_is_direct(ops))
359 		cpu_addr = dma_direct_alloc(dev, size, dma_handle, flag, attrs);
360 	else if (ops->alloc)
361 		cpu_addr = ops->alloc(dev, size, dma_handle, flag, attrs);
362 	else
363 		return NULL;
364 
365 	debug_dma_alloc_coherent(dev, size, *dma_handle, cpu_addr);
366 	return cpu_addr;
367 }
368 EXPORT_SYMBOL(dma_alloc_attrs);
369 
370 void dma_free_attrs(struct device *dev, size_t size, void *cpu_addr,
371 		dma_addr_t dma_handle, unsigned long attrs)
372 {
373 	const struct dma_map_ops *ops = get_dma_ops(dev);
374 
375 	if (dma_release_from_dev_coherent(dev, get_order(size), cpu_addr))
376 		return;
377 	/*
378 	 * On non-coherent platforms which implement DMA-coherent buffers via
379 	 * non-cacheable remaps, ops->free() may call vunmap(). Thus getting
380 	 * this far in IRQ context is a) at risk of a BUG_ON() or trying to
381 	 * sleep on some machines, and b) an indication that the driver is
382 	 * probably misusing the coherent API anyway.
383 	 */
384 	WARN_ON(irqs_disabled());
385 
386 	if (!cpu_addr)
387 		return;
388 
389 	debug_dma_free_coherent(dev, size, cpu_addr, dma_handle);
390 	if (dma_is_direct(ops))
391 		dma_direct_free(dev, size, cpu_addr, dma_handle, attrs);
392 	else if (ops->free)
393 		ops->free(dev, size, cpu_addr, dma_handle, attrs);
394 }
395 EXPORT_SYMBOL(dma_free_attrs);
396 
397 static inline void dma_check_mask(struct device *dev, u64 mask)
398 {
399 	if (sme_active() && (mask < (((u64)sme_get_me_mask() << 1) - 1)))
400 		dev_warn(dev, "SME is active, device will require DMA bounce buffers\n");
401 }
402 
403 int dma_supported(struct device *dev, u64 mask)
404 {
405 	const struct dma_map_ops *ops = get_dma_ops(dev);
406 
407 	if (dma_is_direct(ops))
408 		return dma_direct_supported(dev, mask);
409 	if (!ops->dma_supported)
410 		return 1;
411 	return ops->dma_supported(dev, mask);
412 }
413 EXPORT_SYMBOL(dma_supported);
414 
415 #ifndef HAVE_ARCH_DMA_SET_MASK
416 int dma_set_mask(struct device *dev, u64 mask)
417 {
418 	if (!dev->dma_mask || !dma_supported(dev, mask))
419 		return -EIO;
420 
421 	dma_check_mask(dev, mask);
422 	*dev->dma_mask = mask;
423 	return 0;
424 }
425 EXPORT_SYMBOL(dma_set_mask);
426 #endif
427 
428 #ifndef CONFIG_ARCH_HAS_DMA_SET_COHERENT_MASK
429 int dma_set_coherent_mask(struct device *dev, u64 mask)
430 {
431 	if (!dma_supported(dev, mask))
432 		return -EIO;
433 
434 	dma_check_mask(dev, mask);
435 	dev->coherent_dma_mask = mask;
436 	return 0;
437 }
438 EXPORT_SYMBOL(dma_set_coherent_mask);
439 #endif
440 
441 void dma_cache_sync(struct device *dev, void *vaddr, size_t size,
442 		enum dma_data_direction dir)
443 {
444 	const struct dma_map_ops *ops = get_dma_ops(dev);
445 
446 	BUG_ON(!valid_dma_direction(dir));
447 
448 	if (dma_is_direct(ops))
449 		arch_dma_cache_sync(dev, vaddr, size, dir);
450 	else if (ops->cache_sync)
451 		ops->cache_sync(dev, vaddr, size, dir);
452 }
453 EXPORT_SYMBOL(dma_cache_sync);
454