Commit | Line | Data |
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b9d47450 SH |
1 | /* |
2 | * drm gem CMA (contiguous memory allocator) helper functions | |
3 | * | |
4 | * Copyright (C) 2012 Sascha Hauer, Pengutronix | |
5 | * | |
6 | * Based on Samsung Exynos code | |
7 | * | |
8 | * Copyright (c) 2011 Samsung Electronics Co., Ltd. | |
9 | * | |
10 | * This program is free software; you can redistribute it and/or | |
11 | * modify it under the terms of the GNU General Public License | |
12 | * as published by the Free Software Foundation; either version 2 | |
13 | * of the License, or (at your option) any later version. | |
14 | * This program is distributed in the hope that it will be useful, | |
15 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
16 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
17 | * GNU General Public License for more details. | |
18 | */ | |
19 | ||
20 | #include <linux/mm.h> | |
21 | #include <linux/slab.h> | |
22 | #include <linux/mutex.h> | |
23 | #include <linux/export.h> | |
71d7282a | 24 | #include <linux/dma-buf.h> |
b9d47450 SH |
25 | #include <linux/dma-mapping.h> |
26 | ||
27 | #include <drm/drmP.h> | |
28 | #include <drm/drm.h> | |
29 | #include <drm/drm_gem_cma_helper.h> | |
0de23977 | 30 | #include <drm/drm_vma_manager.h> |
b9d47450 | 31 | |
d7883f87 TR |
32 | /** |
33 | * DOC: cma helpers | |
34 | * | |
35 | * The Contiguous Memory Allocator reserves a pool of memory at early boot | |
36 | * that is used to service requests for large blocks of contiguous memory. | |
37 | * | |
38 | * The DRM GEM/CMA helpers use this allocator as a means to provide buffer | |
39 | * objects that are physically contiguous in memory. This is useful for | |
40 | * display drivers that are unable to map scattered buffers via an IOMMU. | |
41 | */ | |
42 | ||
43 | /** | |
a5ed8940 | 44 | * __drm_gem_cma_create - Create a GEM CMA object without allocating memory |
d7883f87 TR |
45 | * @drm: DRM device |
46 | * @size: size of the object to allocate | |
b9d47450 | 47 | * |
d7883f87 TR |
48 | * This function creates and initializes a GEM CMA object of the given size, |
49 | * but doesn't allocate any memory to back the object. | |
a5ed8940 | 50 | * |
d7883f87 TR |
51 | * Returns: |
52 | * A struct drm_gem_cma_object * on success or an ERR_PTR()-encoded negative | |
53 | * error code on failure. | |
b9d47450 | 54 | */ |
a5ed8940 | 55 | static struct drm_gem_cma_object * |
d7883f87 | 56 | __drm_gem_cma_create(struct drm_device *drm, size_t size) |
b9d47450 SH |
57 | { |
58 | struct drm_gem_cma_object *cma_obj; | |
59 | struct drm_gem_object *gem_obj; | |
60 | int ret; | |
61 | ||
b9d47450 SH |
62 | cma_obj = kzalloc(sizeof(*cma_obj), GFP_KERNEL); |
63 | if (!cma_obj) | |
64 | return ERR_PTR(-ENOMEM); | |
65 | ||
b9d47450 SH |
66 | gem_obj = &cma_obj->base; |
67 | ||
68 | ret = drm_gem_object_init(drm, gem_obj, size); | |
69 | if (ret) | |
a5ed8940 | 70 | goto error; |
b9d47450 SH |
71 | |
72 | ret = drm_gem_create_mmap_offset(gem_obj); | |
a5ed8940 LP |
73 | if (ret) { |
74 | drm_gem_object_release(gem_obj); | |
75 | goto error; | |
76 | } | |
b9d47450 SH |
77 | |
78 | return cma_obj; | |
79 | ||
a5ed8940 LP |
80 | error: |
81 | kfree(cma_obj); | |
82 | return ERR_PTR(ret); | |
83 | } | |
b9d47450 | 84 | |
d7883f87 | 85 | /** |
a5ed8940 | 86 | * drm_gem_cma_create - allocate an object with the given size |
d7883f87 TR |
87 | * @drm: DRM device |
88 | * @size: size of the object to allocate | |
89 | * | |
90 | * This function creates a CMA GEM object and allocates a contiguous chunk of | |
91 | * memory as backing store. The backing memory has the writecombine attribute | |
92 | * set. | |
a5ed8940 | 93 | * |
d7883f87 TR |
94 | * Returns: |
95 | * A struct drm_gem_cma_object * on success or an ERR_PTR()-encoded negative | |
96 | * error code on failure. | |
a5ed8940 LP |
97 | */ |
98 | struct drm_gem_cma_object *drm_gem_cma_create(struct drm_device *drm, | |
d7883f87 | 99 | size_t size) |
a5ed8940 LP |
100 | { |
101 | struct drm_gem_cma_object *cma_obj; | |
71d7282a | 102 | int ret; |
b9d47450 | 103 | |
a5ed8940 | 104 | size = round_up(size, PAGE_SIZE); |
b9d47450 | 105 | |
a5ed8940 LP |
106 | cma_obj = __drm_gem_cma_create(drm, size); |
107 | if (IS_ERR(cma_obj)) | |
108 | return cma_obj; | |
109 | ||
110 | cma_obj->vaddr = dma_alloc_writecombine(drm->dev, size, | |
111 | &cma_obj->paddr, GFP_KERNEL | __GFP_NOWARN); | |
112 | if (!cma_obj->vaddr) { | |
30c4cf3b | 113 | dev_err(drm->dev, "failed to allocate buffer with size %zu\n", |
a5ed8940 | 114 | size); |
71d7282a LP |
115 | ret = -ENOMEM; |
116 | goto error; | |
117 | } | |
118 | ||
a5ed8940 | 119 | return cma_obj; |
71d7282a LP |
120 | |
121 | error: | |
71d7282a LP |
122 | drm_gem_cma_free_object(&cma_obj->base); |
123 | return ERR_PTR(ret); | |
b9d47450 SH |
124 | } |
125 | EXPORT_SYMBOL_GPL(drm_gem_cma_create); | |
126 | ||
d7883f87 TR |
127 | /** |
128 | * drm_gem_cma_create_with_handle - allocate an object with the given size and | |
129 | * return a GEM handle to it | |
130 | * @file_priv: DRM file-private structure to register the handle for | |
131 | * @drm: DRM device | |
132 | * @size: size of the object to allocate | |
133 | * @handle: return location for the GEM handle | |
134 | * | |
135 | * This function creates a CMA GEM object, allocating a physically contiguous | |
136 | * chunk of memory as backing store. The GEM object is then added to the list | |
137 | * of object associated with the given file and a handle to it is returned. | |
b9d47450 | 138 | * |
d7883f87 TR |
139 | * Returns: |
140 | * A struct drm_gem_cma_object * on success or an ERR_PTR()-encoded negative | |
141 | * error code on failure. | |
b9d47450 | 142 | */ |
d7883f87 TR |
143 | static struct drm_gem_cma_object * |
144 | drm_gem_cma_create_with_handle(struct drm_file *file_priv, | |
145 | struct drm_device *drm, size_t size, | |
146 | uint32_t *handle) | |
b9d47450 SH |
147 | { |
148 | struct drm_gem_cma_object *cma_obj; | |
149 | struct drm_gem_object *gem_obj; | |
150 | int ret; | |
151 | ||
152 | cma_obj = drm_gem_cma_create(drm, size); | |
153 | if (IS_ERR(cma_obj)) | |
154 | return cma_obj; | |
155 | ||
156 | gem_obj = &cma_obj->base; | |
157 | ||
158 | /* | |
159 | * allocate a id of idr table where the obj is registered | |
160 | * and handle has the id what user can see. | |
161 | */ | |
162 | ret = drm_gem_handle_create(file_priv, gem_obj, handle); | |
163 | if (ret) | |
164 | goto err_handle_create; | |
165 | ||
166 | /* drop reference from allocate - handle holds it now. */ | |
167 | drm_gem_object_unreference_unlocked(gem_obj); | |
168 | ||
169 | return cma_obj; | |
170 | ||
171 | err_handle_create: | |
172 | drm_gem_cma_free_object(gem_obj); | |
173 | ||
174 | return ERR_PTR(ret); | |
175 | } | |
176 | ||
d7883f87 TR |
177 | /** |
178 | * drm_gem_cma_free_object - free resources associated with a CMA GEM object | |
179 | * @gem_obj: GEM object to free | |
180 | * | |
181 | * This function frees the backing memory of the CMA GEM object, cleans up the | |
182 | * GEM object state and frees the memory used to store the object itself. | |
183 | * Drivers using the CMA helpers should set this as their DRM driver's | |
184 | * ->gem_free_object() callback. | |
b9d47450 SH |
185 | */ |
186 | void drm_gem_cma_free_object(struct drm_gem_object *gem_obj) | |
187 | { | |
188 | struct drm_gem_cma_object *cma_obj; | |
189 | ||
b9d47450 SH |
190 | cma_obj = to_drm_gem_cma_obj(gem_obj); |
191 | ||
71d7282a | 192 | if (cma_obj->vaddr) { |
a5ed8940 LP |
193 | dma_free_writecombine(gem_obj->dev->dev, cma_obj->base.size, |
194 | cma_obj->vaddr, cma_obj->paddr); | |
71d7282a LP |
195 | } else if (gem_obj->import_attach) { |
196 | drm_prime_gem_destroy(gem_obj, cma_obj->sgt); | |
197 | } | |
a5ed8940 LP |
198 | |
199 | drm_gem_object_release(gem_obj); | |
b9d47450 SH |
200 | |
201 | kfree(cma_obj); | |
202 | } | |
203 | EXPORT_SYMBOL_GPL(drm_gem_cma_free_object); | |
204 | ||
6d178291 TR |
205 | /** |
206 | * drm_gem_cma_dumb_create_internal - create a dumb buffer object | |
207 | * @file_priv: DRM file-private structure to create the dumb buffer for | |
208 | * @drm: DRM device | |
209 | * @args: IOCTL data | |
210 | * | |
211 | * This aligns the pitch and size arguments to the minimum required. This is | |
212 | * an internal helper that can be wrapped by a driver to account for hardware | |
213 | * with more specific alignment requirements. It should not be used directly | |
214 | * as the ->dumb_create() callback in a DRM driver. | |
215 | * | |
216 | * Returns: | |
217 | * 0 on success or a negative error code on failure. | |
218 | */ | |
219 | int drm_gem_cma_dumb_create_internal(struct drm_file *file_priv, | |
220 | struct drm_device *drm, | |
221 | struct drm_mode_create_dumb *args) | |
222 | { | |
223 | unsigned int min_pitch = DIV_ROUND_UP(args->width * args->bpp, 8); | |
224 | struct drm_gem_cma_object *cma_obj; | |
225 | ||
226 | if (args->pitch < min_pitch) | |
227 | args->pitch = min_pitch; | |
228 | ||
229 | if (args->size < args->pitch * args->height) | |
230 | args->size = args->pitch * args->height; | |
231 | ||
232 | cma_obj = drm_gem_cma_create_with_handle(file_priv, drm, args->size, | |
233 | &args->handle); | |
234 | return PTR_ERR_OR_ZERO(cma_obj); | |
235 | } | |
236 | EXPORT_SYMBOL_GPL(drm_gem_cma_dumb_create_internal); | |
237 | ||
d7883f87 TR |
238 | /** |
239 | * drm_gem_cma_dumb_create - create a dumb buffer object | |
240 | * @file_priv: DRM file-private structure to create the dumb buffer for | |
241 | * @drm: DRM device | |
242 | * @args: IOCTL data | |
243 | * | |
244 | * This function computes the pitch of the dumb buffer and rounds it up to an | |
245 | * integer number of bytes per pixel. Drivers for hardware that doesn't have | |
246 | * any additional restrictions on the pitch can directly use this function as | |
247 | * their ->dumb_create() callback. | |
b9d47450 | 248 | * |
6d178291 TR |
249 | * For hardware with additional restrictions, drivers can adjust the fields |
250 | * set up by userspace and pass the IOCTL data along to the | |
251 | * drm_gem_cma_dumb_create_internal() function. | |
252 | * | |
d7883f87 TR |
253 | * Returns: |
254 | * 0 on success or a negative error code on failure. | |
b9d47450 SH |
255 | */ |
256 | int drm_gem_cma_dumb_create(struct drm_file *file_priv, | |
d7883f87 TR |
257 | struct drm_device *drm, |
258 | struct drm_mode_create_dumb *args) | |
b9d47450 SH |
259 | { |
260 | struct drm_gem_cma_object *cma_obj; | |
b9d47450 | 261 | |
6d178291 TR |
262 | args->pitch = DIV_ROUND_UP(args->width * args->bpp, 8); |
263 | args->size = args->pitch * args->height; | |
b9d47450 | 264 | |
d7883f87 TR |
265 | cma_obj = drm_gem_cma_create_with_handle(file_priv, drm, args->size, |
266 | &args->handle); | |
b03cda51 | 267 | return PTR_ERR_OR_ZERO(cma_obj); |
b9d47450 SH |
268 | } |
269 | EXPORT_SYMBOL_GPL(drm_gem_cma_dumb_create); | |
270 | ||
d7883f87 TR |
271 | /** |
272 | * drm_gem_cma_dumb_map_offset - return the fake mmap offset for a CMA GEM | |
273 | * object | |
274 | * @file_priv: DRM file-private structure containing the GEM object | |
275 | * @drm: DRM device | |
276 | * @handle: GEM object handle | |
277 | * @offset: return location for the fake mmap offset | |
278 | * | |
279 | * This function look up an object by its handle and returns the fake mmap | |
280 | * offset associated with it. Drivers using the CMA helpers should set this | |
281 | * as their DRM driver's ->dumb_map_offset() callback. | |
282 | * | |
283 | * Returns: | |
284 | * 0 on success or a negative error code on failure. | |
b9d47450 SH |
285 | */ |
286 | int drm_gem_cma_dumb_map_offset(struct drm_file *file_priv, | |
d7883f87 TR |
287 | struct drm_device *drm, u32 handle, |
288 | u64 *offset) | |
b9d47450 SH |
289 | { |
290 | struct drm_gem_object *gem_obj; | |
291 | ||
b9d47450 SH |
292 | gem_obj = drm_gem_object_lookup(drm, file_priv, handle); |
293 | if (!gem_obj) { | |
d7883f87 | 294 | dev_err(drm->dev, "failed to lookup GEM object\n"); |
b9d47450 SH |
295 | return -EINVAL; |
296 | } | |
297 | ||
0de23977 | 298 | *offset = drm_vma_node_offset_addr(&gem_obj->vma_node); |
b9d47450 | 299 | |
141518b6 | 300 | drm_gem_object_unreference_unlocked(gem_obj); |
b9d47450 SH |
301 | |
302 | return 0; | |
303 | } | |
304 | EXPORT_SYMBOL_GPL(drm_gem_cma_dumb_map_offset); | |
305 | ||
306 | const struct vm_operations_struct drm_gem_cma_vm_ops = { | |
307 | .open = drm_gem_vm_open, | |
308 | .close = drm_gem_vm_close, | |
309 | }; | |
310 | EXPORT_SYMBOL_GPL(drm_gem_cma_vm_ops); | |
311 | ||
ebaf9e03 LP |
312 | static int drm_gem_cma_mmap_obj(struct drm_gem_cma_object *cma_obj, |
313 | struct vm_area_struct *vma) | |
314 | { | |
315 | int ret; | |
316 | ||
b65e64f7 LP |
317 | /* |
318 | * Clear the VM_PFNMAP flag that was set by drm_gem_mmap(), and set the | |
319 | * vm_pgoff (used as a fake buffer offset by DRM) to 0 as we want to map | |
320 | * the whole buffer. | |
321 | */ | |
322 | vma->vm_flags &= ~VM_PFNMAP; | |
323 | vma->vm_pgoff = 0; | |
324 | ||
325 | ret = dma_mmap_writecombine(cma_obj->base.dev->dev, vma, | |
326 | cma_obj->vaddr, cma_obj->paddr, | |
327 | vma->vm_end - vma->vm_start); | |
ebaf9e03 LP |
328 | if (ret) |
329 | drm_gem_vm_close(vma); | |
330 | ||
331 | return ret; | |
332 | } | |
333 | ||
d7883f87 TR |
334 | /** |
335 | * drm_gem_cma_mmap - memory-map a CMA GEM object | |
336 | * @filp: file object | |
337 | * @vma: VMA for the area to be mapped | |
338 | * | |
339 | * This function implements an augmented version of the GEM DRM file mmap | |
340 | * operation for CMA objects: In addition to the usual GEM VMA setup it | |
341 | * immediately faults in the entire object instead of using on-demaind | |
342 | * faulting. Drivers which employ the CMA helpers should use this function | |
343 | * as their ->mmap() handler in the DRM device file's file_operations | |
344 | * structure. | |
345 | * | |
346 | * Returns: | |
347 | * 0 on success or a negative error code on failure. | |
b9d47450 SH |
348 | */ |
349 | int drm_gem_cma_mmap(struct file *filp, struct vm_area_struct *vma) | |
350 | { | |
b9d47450 | 351 | struct drm_gem_cma_object *cma_obj; |
ebaf9e03 | 352 | struct drm_gem_object *gem_obj; |
b9d47450 SH |
353 | int ret; |
354 | ||
355 | ret = drm_gem_mmap(filp, vma); | |
356 | if (ret) | |
357 | return ret; | |
358 | ||
359 | gem_obj = vma->vm_private_data; | |
360 | cma_obj = to_drm_gem_cma_obj(gem_obj); | |
361 | ||
ebaf9e03 | 362 | return drm_gem_cma_mmap_obj(cma_obj, vma); |
b9d47450 SH |
363 | } |
364 | EXPORT_SYMBOL_GPL(drm_gem_cma_mmap); | |
365 | ||
6f646095 | 366 | #ifdef CONFIG_DEBUG_FS |
d7883f87 TR |
367 | /** |
368 | * drm_gem_cma_describe - describe a CMA GEM object for debugfs | |
369 | * @cma_obj: CMA GEM object | |
370 | * @m: debugfs file handle | |
371 | * | |
372 | * This function can be used to dump a human-readable representation of the | |
373 | * CMA GEM object into a synthetic file. | |
374 | */ | |
375 | void drm_gem_cma_describe(struct drm_gem_cma_object *cma_obj, | |
376 | struct seq_file *m) | |
6f646095 RC |
377 | { |
378 | struct drm_gem_object *obj = &cma_obj->base; | |
0de23977 | 379 | uint64_t off; |
6f646095 | 380 | |
0de23977 | 381 | off = drm_vma_node_start(&obj->vma_node); |
6f646095 | 382 | |
30c4cf3b | 383 | seq_printf(m, "%2d (%2d) %08llx %pad %p %zu", |
6f646095 | 384 | obj->name, obj->refcount.refcount.counter, |
f4d1b021 | 385 | off, &cma_obj->paddr, cma_obj->vaddr, obj->size); |
6f646095 RC |
386 | |
387 | seq_printf(m, "\n"); | |
388 | } | |
389 | EXPORT_SYMBOL_GPL(drm_gem_cma_describe); | |
390 | #endif | |
71d7282a | 391 | |
d7883f87 TR |
392 | /** |
393 | * drm_gem_cma_prime_get_sg_table - provide a scatter/gather table of pinned | |
394 | * pages for a CMA GEM object | |
395 | * @obj: GEM object | |
396 | * | |
397 | * This function exports a scatter/gather table suitable for PRIME usage by | |
398 | * calling the standard DMA mapping API. Drivers using the CMA helpers should | |
399 | * set this as their DRM driver's ->gem_prime_get_sg_table() callback. | |
400 | * | |
401 | * Returns: | |
402 | * A pointer to the scatter/gather table of pinned pages or NULL on failure. | |
403 | */ | |
78467dc5 JS |
404 | struct sg_table *drm_gem_cma_prime_get_sg_table(struct drm_gem_object *obj) |
405 | { | |
406 | struct drm_gem_cma_object *cma_obj = to_drm_gem_cma_obj(obj); | |
407 | struct sg_table *sgt; | |
408 | int ret; | |
409 | ||
410 | sgt = kzalloc(sizeof(*sgt), GFP_KERNEL); | |
411 | if (!sgt) | |
412 | return NULL; | |
413 | ||
414 | ret = dma_get_sgtable(obj->dev->dev, sgt, cma_obj->vaddr, | |
415 | cma_obj->paddr, obj->size); | |
416 | if (ret < 0) | |
417 | goto out; | |
418 | ||
419 | return sgt; | |
420 | ||
421 | out: | |
422 | kfree(sgt); | |
423 | return NULL; | |
424 | } | |
425 | EXPORT_SYMBOL_GPL(drm_gem_cma_prime_get_sg_table); | |
426 | ||
d7883f87 TR |
427 | /** |
428 | * drm_gem_cma_prime_import_sg_table - produce a CMA GEM object from another | |
429 | * driver's scatter/gather table of pinned pages | |
430 | * @dev: device to import into | |
431 | * @attach: DMA-BUF attachment | |
432 | * @sgt: scatter/gather table of pinned pages | |
433 | * | |
434 | * This function imports a scatter/gather table exported via DMA-BUF by | |
435 | * another driver. Imported buffers must be physically contiguous in memory | |
436 | * (i.e. the scatter/gather table must contain a single entry). Drivers that | |
437 | * use the CMA helpers should set this as their DRM driver's | |
438 | * ->gem_prime_import_sg_table() callback. | |
439 | * | |
440 | * Returns: | |
441 | * A pointer to a newly created GEM object or an ERR_PTR-encoded negative | |
442 | * error code on failure. | |
443 | */ | |
78467dc5 | 444 | struct drm_gem_object * |
b5e9c1a2 ML |
445 | drm_gem_cma_prime_import_sg_table(struct drm_device *dev, |
446 | struct dma_buf_attachment *attach, | |
78467dc5 JS |
447 | struct sg_table *sgt) |
448 | { | |
449 | struct drm_gem_cma_object *cma_obj; | |
450 | ||
451 | if (sgt->nents != 1) | |
452 | return ERR_PTR(-EINVAL); | |
453 | ||
454 | /* Create a CMA GEM buffer. */ | |
b5e9c1a2 | 455 | cma_obj = __drm_gem_cma_create(dev, attach->dmabuf->size); |
78467dc5 | 456 | if (IS_ERR(cma_obj)) |
e7c36347 | 457 | return ERR_CAST(cma_obj); |
78467dc5 JS |
458 | |
459 | cma_obj->paddr = sg_dma_address(sgt->sgl); | |
460 | cma_obj->sgt = sgt; | |
461 | ||
b5e9c1a2 | 462 | DRM_DEBUG_PRIME("dma_addr = %pad, size = %zu\n", &cma_obj->paddr, attach->dmabuf->size); |
78467dc5 JS |
463 | |
464 | return &cma_obj->base; | |
465 | } | |
466 | EXPORT_SYMBOL_GPL(drm_gem_cma_prime_import_sg_table); | |
467 | ||
d7883f87 TR |
468 | /** |
469 | * drm_gem_cma_prime_mmap - memory-map an exported CMA GEM object | |
470 | * @obj: GEM object | |
471 | * @vma: VMA for the area to be mapped | |
472 | * | |
473 | * This function maps a buffer imported via DRM PRIME into a userspace | |
474 | * process's address space. Drivers that use the CMA helpers should set this | |
475 | * as their DRM driver's ->gem_prime_mmap() callback. | |
476 | * | |
477 | * Returns: | |
478 | * 0 on success or a negative error code on failure. | |
479 | */ | |
78467dc5 JS |
480 | int drm_gem_cma_prime_mmap(struct drm_gem_object *obj, |
481 | struct vm_area_struct *vma) | |
482 | { | |
483 | struct drm_gem_cma_object *cma_obj; | |
484 | struct drm_device *dev = obj->dev; | |
485 | int ret; | |
486 | ||
487 | mutex_lock(&dev->struct_mutex); | |
488 | ret = drm_gem_mmap_obj(obj, obj->size, vma); | |
489 | mutex_unlock(&dev->struct_mutex); | |
490 | if (ret < 0) | |
491 | return ret; | |
492 | ||
493 | cma_obj = to_drm_gem_cma_obj(obj); | |
494 | return drm_gem_cma_mmap_obj(cma_obj, vma); | |
495 | } | |
496 | EXPORT_SYMBOL_GPL(drm_gem_cma_prime_mmap); | |
497 | ||
d7883f87 TR |
498 | /** |
499 | * drm_gem_cma_prime_vmap - map a CMA GEM object into the kernel's virtual | |
500 | * address space | |
501 | * @obj: GEM object | |
502 | * | |
503 | * This function maps a buffer exported via DRM PRIME into the kernel's | |
504 | * virtual address space. Since the CMA buffers are already mapped into the | |
505 | * kernel virtual address space this simply returns the cached virtual | |
506 | * address. Drivers using the CMA helpers should set this as their DRM | |
507 | * driver's ->gem_prime_vmap() callback. | |
508 | * | |
509 | * Returns: | |
510 | * The kernel virtual address of the CMA GEM object's backing store. | |
511 | */ | |
78467dc5 JS |
512 | void *drm_gem_cma_prime_vmap(struct drm_gem_object *obj) |
513 | { | |
514 | struct drm_gem_cma_object *cma_obj = to_drm_gem_cma_obj(obj); | |
515 | ||
516 | return cma_obj->vaddr; | |
517 | } | |
518 | EXPORT_SYMBOL_GPL(drm_gem_cma_prime_vmap); | |
519 | ||
d7883f87 TR |
520 | /** |
521 | * drm_gem_cma_prime_vunmap - unmap a CMA GEM object from the kernel's virtual | |
522 | * address space | |
523 | * @obj: GEM object | |
524 | * @vaddr: kernel virtual address where the CMA GEM object was mapped | |
525 | * | |
526 | * This function removes a buffer exported via DRM PRIME from the kernel's | |
527 | * virtual address space. This is a no-op because CMA buffers cannot be | |
528 | * unmapped from kernel space. Drivers using the CMA helpers should set this | |
529 | * as their DRM driver's ->gem_prime_vunmap() callback. | |
530 | */ | |
78467dc5 JS |
531 | void drm_gem_cma_prime_vunmap(struct drm_gem_object *obj, void *vaddr) |
532 | { | |
533 | /* Nothing to do */ | |
534 | } | |
535 | EXPORT_SYMBOL_GPL(drm_gem_cma_prime_vunmap); |