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2194a63a NT |
1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* | |
3 | * Copyright 2018 Noralf Trønnes | |
4 | */ | |
5 | ||
6 | #include <linux/dma-buf.h> | |
7 | #include <linux/export.h> | |
8 | #include <linux/mutex.h> | |
9 | #include <linux/shmem_fs.h> | |
10 | #include <linux/slab.h> | |
11 | #include <linux/vmalloc.h> | |
12 | ||
d3ea256a | 13 | #include <drm/drm.h> |
2194a63a NT |
14 | #include <drm/drm_device.h> |
15 | #include <drm/drm_drv.h> | |
16 | #include <drm/drm_gem_shmem_helper.h> | |
17 | #include <drm/drm_prime.h> | |
18 | #include <drm/drm_print.h> | |
19 | ||
20 | /** | |
21 | * DOC: overview | |
22 | * | |
23 | * This library provides helpers for GEM objects backed by shmem buffers | |
24 | * allocated using anonymous pageable memory. | |
25 | */ | |
26 | ||
27 | static const struct drm_gem_object_funcs drm_gem_shmem_funcs = { | |
28 | .free = drm_gem_shmem_free_object, | |
29 | .print_info = drm_gem_shmem_print_info, | |
30 | .pin = drm_gem_shmem_pin, | |
31 | .unpin = drm_gem_shmem_unpin, | |
32 | .get_sg_table = drm_gem_shmem_get_sg_table, | |
33 | .vmap = drm_gem_shmem_vmap, | |
34 | .vunmap = drm_gem_shmem_vunmap, | |
35 | .vm_ops = &drm_gem_shmem_vm_ops, | |
36 | }; | |
37 | ||
38 | /** | |
39 | * drm_gem_shmem_create - Allocate an object with the given size | |
40 | * @dev: DRM device | |
41 | * @size: Size of the object to allocate | |
42 | * | |
43 | * This function creates a shmem GEM object. | |
44 | * | |
45 | * Returns: | |
46 | * A struct drm_gem_shmem_object * on success or an ERR_PTR()-encoded negative | |
47 | * error code on failure. | |
48 | */ | |
49 | struct drm_gem_shmem_object *drm_gem_shmem_create(struct drm_device *dev, size_t size) | |
50 | { | |
51 | struct drm_gem_shmem_object *shmem; | |
52 | struct drm_gem_object *obj; | |
53 | int ret; | |
54 | ||
55 | size = PAGE_ALIGN(size); | |
56 | ||
57 | if (dev->driver->gem_create_object) | |
58 | obj = dev->driver->gem_create_object(dev, size); | |
59 | else | |
60 | obj = kzalloc(sizeof(*shmem), GFP_KERNEL); | |
61 | if (!obj) | |
62 | return ERR_PTR(-ENOMEM); | |
63 | ||
64 | if (!obj->funcs) | |
65 | obj->funcs = &drm_gem_shmem_funcs; | |
66 | ||
67 | ret = drm_gem_object_init(dev, obj, size); | |
68 | if (ret) | |
69 | goto err_free; | |
70 | ||
71 | ret = drm_gem_create_mmap_offset(obj); | |
72 | if (ret) | |
73 | goto err_release; | |
74 | ||
75 | shmem = to_drm_gem_shmem_obj(obj); | |
76 | mutex_init(&shmem->pages_lock); | |
77 | mutex_init(&shmem->vmap_lock); | |
17acb9f3 | 78 | INIT_LIST_HEAD(&shmem->madv_list); |
2194a63a NT |
79 | |
80 | /* | |
81 | * Our buffers are kept pinned, so allocating them | |
82 | * from the MOVABLE zone is a really bad idea, and | |
83 | * conflicts with CMA. See comments above new_inode() | |
84 | * why this is required _and_ expected if you're | |
85 | * going to pin these pages. | |
86 | */ | |
87 | mapping_set_gfp_mask(obj->filp->f_mapping, GFP_HIGHUSER | | |
88 | __GFP_RETRY_MAYFAIL | __GFP_NOWARN); | |
89 | ||
90 | return shmem; | |
91 | ||
92 | err_release: | |
93 | drm_gem_object_release(obj); | |
94 | err_free: | |
95 | kfree(obj); | |
96 | ||
97 | return ERR_PTR(ret); | |
98 | } | |
99 | EXPORT_SYMBOL_GPL(drm_gem_shmem_create); | |
100 | ||
101 | /** | |
102 | * drm_gem_shmem_free_object - Free resources associated with a shmem GEM object | |
103 | * @obj: GEM object to free | |
104 | * | |
105 | * This function cleans up the GEM object state and frees the memory used to | |
106 | * store the object itself. | |
107 | */ | |
108 | void drm_gem_shmem_free_object(struct drm_gem_object *obj) | |
109 | { | |
110 | struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj); | |
111 | ||
112 | WARN_ON(shmem->vmap_use_count); | |
113 | ||
114 | if (obj->import_attach) { | |
115 | shmem->pages_use_count--; | |
116 | drm_prime_gem_destroy(obj, shmem->sgt); | |
117 | kvfree(shmem->pages); | |
118 | } else { | |
119 | if (shmem->sgt) { | |
120 | dma_unmap_sg(obj->dev->dev, shmem->sgt->sgl, | |
121 | shmem->sgt->nents, DMA_BIDIRECTIONAL); | |
2194a63a NT |
122 | sg_free_table(shmem->sgt); |
123 | kfree(shmem->sgt); | |
124 | } | |
3bf5189d RH |
125 | if (shmem->pages) |
126 | drm_gem_shmem_put_pages(shmem); | |
2194a63a NT |
127 | } |
128 | ||
129 | WARN_ON(shmem->pages_use_count); | |
130 | ||
131 | drm_gem_object_release(obj); | |
132 | mutex_destroy(&shmem->pages_lock); | |
133 | mutex_destroy(&shmem->vmap_lock); | |
134 | kfree(shmem); | |
135 | } | |
136 | EXPORT_SYMBOL_GPL(drm_gem_shmem_free_object); | |
137 | ||
138 | static int drm_gem_shmem_get_pages_locked(struct drm_gem_shmem_object *shmem) | |
139 | { | |
140 | struct drm_gem_object *obj = &shmem->base; | |
141 | struct page **pages; | |
142 | ||
143 | if (shmem->pages_use_count++ > 0) | |
144 | return 0; | |
145 | ||
146 | pages = drm_gem_get_pages(obj); | |
147 | if (IS_ERR(pages)) { | |
148 | DRM_DEBUG_KMS("Failed to get pages (%ld)\n", PTR_ERR(pages)); | |
149 | shmem->pages_use_count = 0; | |
150 | return PTR_ERR(pages); | |
151 | } | |
152 | ||
153 | shmem->pages = pages; | |
154 | ||
155 | return 0; | |
156 | } | |
157 | ||
158 | /* | |
159 | * drm_gem_shmem_get_pages - Allocate backing pages for a shmem GEM object | |
160 | * @shmem: shmem GEM object | |
161 | * | |
162 | * This function makes sure that backing pages exists for the shmem GEM object | |
163 | * and increases the use count. | |
164 | * | |
165 | * Returns: | |
166 | * 0 on success or a negative error code on failure. | |
167 | */ | |
168 | int drm_gem_shmem_get_pages(struct drm_gem_shmem_object *shmem) | |
169 | { | |
170 | int ret; | |
171 | ||
172 | ret = mutex_lock_interruptible(&shmem->pages_lock); | |
173 | if (ret) | |
174 | return ret; | |
175 | ret = drm_gem_shmem_get_pages_locked(shmem); | |
176 | mutex_unlock(&shmem->pages_lock); | |
177 | ||
178 | return ret; | |
179 | } | |
180 | EXPORT_SYMBOL(drm_gem_shmem_get_pages); | |
181 | ||
182 | static void drm_gem_shmem_put_pages_locked(struct drm_gem_shmem_object *shmem) | |
183 | { | |
184 | struct drm_gem_object *obj = &shmem->base; | |
185 | ||
186 | if (WARN_ON_ONCE(!shmem->pages_use_count)) | |
187 | return; | |
188 | ||
189 | if (--shmem->pages_use_count > 0) | |
190 | return; | |
191 | ||
192 | drm_gem_put_pages(obj, shmem->pages, | |
193 | shmem->pages_mark_dirty_on_put, | |
194 | shmem->pages_mark_accessed_on_put); | |
195 | shmem->pages = NULL; | |
196 | } | |
197 | ||
198 | /* | |
199 | * drm_gem_shmem_put_pages - Decrease use count on the backing pages for a shmem GEM object | |
200 | * @shmem: shmem GEM object | |
201 | * | |
202 | * This function decreases the use count and puts the backing pages when use drops to zero. | |
203 | */ | |
204 | void drm_gem_shmem_put_pages(struct drm_gem_shmem_object *shmem) | |
205 | { | |
206 | mutex_lock(&shmem->pages_lock); | |
207 | drm_gem_shmem_put_pages_locked(shmem); | |
208 | mutex_unlock(&shmem->pages_lock); | |
209 | } | |
210 | EXPORT_SYMBOL(drm_gem_shmem_put_pages); | |
211 | ||
212 | /** | |
213 | * drm_gem_shmem_pin - Pin backing pages for a shmem GEM object | |
214 | * @obj: GEM object | |
215 | * | |
216 | * This function makes sure the backing pages are pinned in memory while the | |
217 | * buffer is exported. | |
218 | * | |
219 | * Returns: | |
220 | * 0 on success or a negative error code on failure. | |
221 | */ | |
222 | int drm_gem_shmem_pin(struct drm_gem_object *obj) | |
223 | { | |
224 | struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj); | |
225 | ||
226 | return drm_gem_shmem_get_pages(shmem); | |
227 | } | |
228 | EXPORT_SYMBOL(drm_gem_shmem_pin); | |
229 | ||
230 | /** | |
231 | * drm_gem_shmem_unpin - Unpin backing pages for a shmem GEM object | |
232 | * @obj: GEM object | |
233 | * | |
234 | * This function removes the requirement that the backing pages are pinned in | |
235 | * memory. | |
236 | */ | |
237 | void drm_gem_shmem_unpin(struct drm_gem_object *obj) | |
238 | { | |
239 | struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj); | |
240 | ||
241 | drm_gem_shmem_put_pages(shmem); | |
242 | } | |
243 | EXPORT_SYMBOL(drm_gem_shmem_unpin); | |
244 | ||
245 | static void *drm_gem_shmem_vmap_locked(struct drm_gem_shmem_object *shmem) | |
246 | { | |
247 | struct drm_gem_object *obj = &shmem->base; | |
248 | int ret; | |
249 | ||
250 | if (shmem->vmap_use_count++ > 0) | |
251 | return shmem->vaddr; | |
252 | ||
253 | ret = drm_gem_shmem_get_pages(shmem); | |
254 | if (ret) | |
255 | goto err_zero_use; | |
256 | ||
257 | if (obj->import_attach) | |
258 | shmem->vaddr = dma_buf_vmap(obj->import_attach->dmabuf); | |
259 | else | |
be7d9f05 BB |
260 | shmem->vaddr = vmap(shmem->pages, obj->size >> PAGE_SHIFT, |
261 | VM_MAP, pgprot_writecombine(PAGE_KERNEL)); | |
2194a63a NT |
262 | |
263 | if (!shmem->vaddr) { | |
264 | DRM_DEBUG_KMS("Failed to vmap pages\n"); | |
265 | ret = -ENOMEM; | |
266 | goto err_put_pages; | |
267 | } | |
268 | ||
269 | return shmem->vaddr; | |
270 | ||
271 | err_put_pages: | |
272 | drm_gem_shmem_put_pages(shmem); | |
273 | err_zero_use: | |
274 | shmem->vmap_use_count = 0; | |
275 | ||
276 | return ERR_PTR(ret); | |
277 | } | |
278 | ||
279 | /* | |
280 | * drm_gem_shmem_vmap - Create a virtual mapping for a shmem GEM object | |
281 | * @shmem: shmem GEM object | |
282 | * | |
283 | * This function makes sure that a virtual address exists for the buffer backing | |
284 | * the shmem GEM object. | |
285 | * | |
286 | * Returns: | |
287 | * 0 on success or a negative error code on failure. | |
288 | */ | |
289 | void *drm_gem_shmem_vmap(struct drm_gem_object *obj) | |
290 | { | |
291 | struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj); | |
292 | void *vaddr; | |
293 | int ret; | |
294 | ||
295 | ret = mutex_lock_interruptible(&shmem->vmap_lock); | |
296 | if (ret) | |
297 | return ERR_PTR(ret); | |
298 | vaddr = drm_gem_shmem_vmap_locked(shmem); | |
299 | mutex_unlock(&shmem->vmap_lock); | |
300 | ||
301 | return vaddr; | |
302 | } | |
303 | EXPORT_SYMBOL(drm_gem_shmem_vmap); | |
304 | ||
305 | static void drm_gem_shmem_vunmap_locked(struct drm_gem_shmem_object *shmem) | |
306 | { | |
307 | struct drm_gem_object *obj = &shmem->base; | |
308 | ||
309 | if (WARN_ON_ONCE(!shmem->vmap_use_count)) | |
310 | return; | |
311 | ||
312 | if (--shmem->vmap_use_count > 0) | |
313 | return; | |
314 | ||
315 | if (obj->import_attach) | |
316 | dma_buf_vunmap(obj->import_attach->dmabuf, shmem->vaddr); | |
317 | else | |
318 | vunmap(shmem->vaddr); | |
319 | ||
320 | shmem->vaddr = NULL; | |
321 | drm_gem_shmem_put_pages(shmem); | |
322 | } | |
323 | ||
324 | /* | |
325 | * drm_gem_shmem_vunmap - Unmap a virtual mapping fo a shmem GEM object | |
326 | * @shmem: shmem GEM object | |
327 | * | |
328 | * This function removes the virtual address when use count drops to zero. | |
329 | */ | |
330 | void drm_gem_shmem_vunmap(struct drm_gem_object *obj, void *vaddr) | |
331 | { | |
332 | struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj); | |
333 | ||
334 | mutex_lock(&shmem->vmap_lock); | |
335 | drm_gem_shmem_vunmap_locked(shmem); | |
336 | mutex_unlock(&shmem->vmap_lock); | |
337 | } | |
338 | EXPORT_SYMBOL(drm_gem_shmem_vunmap); | |
339 | ||
340 | struct drm_gem_shmem_object * | |
341 | drm_gem_shmem_create_with_handle(struct drm_file *file_priv, | |
342 | struct drm_device *dev, size_t size, | |
343 | uint32_t *handle) | |
344 | { | |
345 | struct drm_gem_shmem_object *shmem; | |
346 | int ret; | |
347 | ||
348 | shmem = drm_gem_shmem_create(dev, size); | |
349 | if (IS_ERR(shmem)) | |
350 | return shmem; | |
351 | ||
352 | /* | |
353 | * Allocate an id of idr table where the obj is registered | |
354 | * and handle has the id what user can see. | |
355 | */ | |
356 | ret = drm_gem_handle_create(file_priv, &shmem->base, handle); | |
357 | /* drop reference from allocate - handle holds it now. */ | |
358 | drm_gem_object_put_unlocked(&shmem->base); | |
359 | if (ret) | |
360 | return ERR_PTR(ret); | |
361 | ||
362 | return shmem; | |
363 | } | |
364 | EXPORT_SYMBOL(drm_gem_shmem_create_with_handle); | |
365 | ||
17acb9f3 RH |
366 | /* Update madvise status, returns true if not purged, else |
367 | * false or -errno. | |
368 | */ | |
369 | int drm_gem_shmem_madvise(struct drm_gem_object *obj, int madv) | |
370 | { | |
371 | struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj); | |
372 | ||
373 | mutex_lock(&shmem->pages_lock); | |
374 | ||
375 | if (shmem->madv >= 0) | |
376 | shmem->madv = madv; | |
377 | ||
378 | madv = shmem->madv; | |
379 | ||
380 | mutex_unlock(&shmem->pages_lock); | |
381 | ||
382 | return (madv >= 0); | |
383 | } | |
384 | EXPORT_SYMBOL(drm_gem_shmem_madvise); | |
385 | ||
386 | void drm_gem_shmem_purge_locked(struct drm_gem_object *obj) | |
387 | { | |
388 | struct drm_device *dev = obj->dev; | |
389 | struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj); | |
390 | ||
391 | WARN_ON(!drm_gem_shmem_is_purgeable(shmem)); | |
392 | ||
4fa3d66f RH |
393 | dma_unmap_sg(obj->dev->dev, shmem->sgt->sgl, |
394 | shmem->sgt->nents, DMA_BIDIRECTIONAL); | |
395 | sg_free_table(shmem->sgt); | |
396 | kfree(shmem->sgt); | |
397 | shmem->sgt = NULL; | |
398 | ||
17acb9f3 RH |
399 | drm_gem_shmem_put_pages_locked(shmem); |
400 | ||
401 | shmem->madv = -1; | |
402 | ||
403 | drm_vma_node_unmap(&obj->vma_node, dev->anon_inode->i_mapping); | |
404 | drm_gem_free_mmap_offset(obj); | |
405 | ||
406 | /* Our goal here is to return as much of the memory as | |
407 | * is possible back to the system as we are called from OOM. | |
408 | * To do this we must instruct the shmfs to drop all of its | |
409 | * backing pages, *now*. | |
410 | */ | |
411 | shmem_truncate_range(file_inode(obj->filp), 0, (loff_t)-1); | |
412 | ||
413 | invalidate_mapping_pages(file_inode(obj->filp)->i_mapping, | |
414 | 0, (loff_t)-1); | |
415 | } | |
416 | EXPORT_SYMBOL(drm_gem_shmem_purge_locked); | |
417 | ||
dfbc7a46 | 418 | bool drm_gem_shmem_purge(struct drm_gem_object *obj) |
17acb9f3 RH |
419 | { |
420 | struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj); | |
421 | ||
dfbc7a46 RH |
422 | if (!mutex_trylock(&shmem->pages_lock)) |
423 | return false; | |
17acb9f3 RH |
424 | drm_gem_shmem_purge_locked(obj); |
425 | mutex_unlock(&shmem->pages_lock); | |
dfbc7a46 RH |
426 | |
427 | return true; | |
17acb9f3 RH |
428 | } |
429 | EXPORT_SYMBOL(drm_gem_shmem_purge); | |
430 | ||
2194a63a NT |
431 | /** |
432 | * drm_gem_shmem_dumb_create - Create a dumb shmem buffer object | |
433 | * @file: DRM file structure to create the dumb buffer for | |
434 | * @dev: DRM device | |
435 | * @args: IOCTL data | |
436 | * | |
437 | * This function computes the pitch of the dumb buffer and rounds it up to an | |
438 | * integer number of bytes per pixel. Drivers for hardware that doesn't have | |
439 | * any additional restrictions on the pitch can directly use this function as | |
440 | * their &drm_driver.dumb_create callback. | |
441 | * | |
442 | * For hardware with additional restrictions, drivers can adjust the fields | |
443 | * set up by userspace before calling into this function. | |
444 | * | |
445 | * Returns: | |
446 | * 0 on success or a negative error code on failure. | |
447 | */ | |
448 | int drm_gem_shmem_dumb_create(struct drm_file *file, struct drm_device *dev, | |
449 | struct drm_mode_create_dumb *args) | |
450 | { | |
451 | u32 min_pitch = DIV_ROUND_UP(args->width * args->bpp, 8); | |
452 | struct drm_gem_shmem_object *shmem; | |
453 | ||
454 | if (!args->pitch || !args->size) { | |
455 | args->pitch = min_pitch; | |
456 | args->size = args->pitch * args->height; | |
457 | } else { | |
458 | /* ensure sane minimum values */ | |
459 | if (args->pitch < min_pitch) | |
460 | args->pitch = min_pitch; | |
461 | if (args->size < args->pitch * args->height) | |
462 | args->size = args->pitch * args->height; | |
463 | } | |
464 | ||
465 | shmem = drm_gem_shmem_create_with_handle(file, dev, args->size, &args->handle); | |
466 | ||
467 | return PTR_ERR_OR_ZERO(shmem); | |
468 | } | |
469 | EXPORT_SYMBOL_GPL(drm_gem_shmem_dumb_create); | |
470 | ||
471 | static vm_fault_t drm_gem_shmem_fault(struct vm_fault *vmf) | |
472 | { | |
473 | struct vm_area_struct *vma = vmf->vma; | |
474 | struct drm_gem_object *obj = vma->vm_private_data; | |
475 | struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj); | |
476 | loff_t num_pages = obj->size >> PAGE_SHIFT; | |
477 | struct page *page; | |
478 | ||
3a3fe6e7 | 479 | if (vmf->pgoff >= num_pages || WARN_ON_ONCE(!shmem->pages)) |
2194a63a NT |
480 | return VM_FAULT_SIGBUS; |
481 | ||
482 | page = shmem->pages[vmf->pgoff]; | |
483 | ||
484 | return vmf_insert_page(vma, vmf->address, page); | |
485 | } | |
486 | ||
487 | static void drm_gem_shmem_vm_open(struct vm_area_struct *vma) | |
488 | { | |
489 | struct drm_gem_object *obj = vma->vm_private_data; | |
490 | struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj); | |
491 | int ret; | |
492 | ||
493 | ret = drm_gem_shmem_get_pages(shmem); | |
494 | WARN_ON_ONCE(ret != 0); | |
495 | ||
496 | drm_gem_vm_open(vma); | |
497 | } | |
498 | ||
499 | static void drm_gem_shmem_vm_close(struct vm_area_struct *vma) | |
500 | { | |
501 | struct drm_gem_object *obj = vma->vm_private_data; | |
502 | struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj); | |
503 | ||
504 | drm_gem_shmem_put_pages(shmem); | |
505 | drm_gem_vm_close(vma); | |
506 | } | |
507 | ||
508 | const struct vm_operations_struct drm_gem_shmem_vm_ops = { | |
509 | .fault = drm_gem_shmem_fault, | |
510 | .open = drm_gem_shmem_vm_open, | |
511 | .close = drm_gem_shmem_vm_close, | |
512 | }; | |
513 | EXPORT_SYMBOL_GPL(drm_gem_shmem_vm_ops); | |
514 | ||
515 | /** | |
516 | * drm_gem_shmem_mmap - Memory-map a shmem GEM object | |
517 | * @filp: File object | |
518 | * @vma: VMA for the area to be mapped | |
519 | * | |
520 | * This function implements an augmented version of the GEM DRM file mmap | |
521 | * operation for shmem objects. Drivers which employ the shmem helpers should | |
522 | * use this function as their &file_operations.mmap handler in the DRM device file's | |
523 | * file_operations structure. | |
524 | * | |
525 | * Instead of directly referencing this function, drivers should use the | |
526 | * DEFINE_DRM_GEM_SHMEM_FOPS() macro. | |
527 | * | |
528 | * Returns: | |
529 | * 0 on success or a negative error code on failure. | |
530 | */ | |
531 | int drm_gem_shmem_mmap(struct file *filp, struct vm_area_struct *vma) | |
532 | { | |
533 | struct drm_gem_shmem_object *shmem; | |
534 | int ret; | |
535 | ||
536 | ret = drm_gem_mmap(filp, vma); | |
537 | if (ret) | |
538 | return ret; | |
539 | ||
540 | shmem = to_drm_gem_shmem_obj(vma->vm_private_data); | |
541 | ||
542 | ret = drm_gem_shmem_get_pages(shmem); | |
543 | if (ret) { | |
544 | drm_gem_vm_close(vma); | |
545 | return ret; | |
546 | } | |
547 | ||
548 | /* VM_PFNMAP was set by drm_gem_mmap() */ | |
549 | vma->vm_flags &= ~VM_PFNMAP; | |
550 | vma->vm_flags |= VM_MIXEDMAP; | |
551 | ||
552 | /* Remove the fake offset */ | |
553 | vma->vm_pgoff -= drm_vma_node_start(&shmem->base.vma_node); | |
554 | ||
555 | return 0; | |
556 | } | |
557 | EXPORT_SYMBOL_GPL(drm_gem_shmem_mmap); | |
558 | ||
559 | /** | |
560 | * drm_gem_shmem_print_info() - Print &drm_gem_shmem_object info for debugfs | |
561 | * @p: DRM printer | |
562 | * @indent: Tab indentation level | |
563 | * @obj: GEM object | |
564 | */ | |
565 | void drm_gem_shmem_print_info(struct drm_printer *p, unsigned int indent, | |
566 | const struct drm_gem_object *obj) | |
567 | { | |
568 | const struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj); | |
569 | ||
570 | drm_printf_indent(p, indent, "pages_use_count=%u\n", shmem->pages_use_count); | |
571 | drm_printf_indent(p, indent, "vmap_use_count=%u\n", shmem->vmap_use_count); | |
572 | drm_printf_indent(p, indent, "vaddr=%p\n", shmem->vaddr); | |
573 | } | |
574 | EXPORT_SYMBOL(drm_gem_shmem_print_info); | |
575 | ||
576 | /** | |
577 | * drm_gem_shmem_get_sg_table - Provide a scatter/gather table of pinned | |
578 | * pages for a shmem GEM object | |
579 | * @obj: GEM object | |
580 | * | |
581 | * This function exports a scatter/gather table suitable for PRIME usage by | |
582 | * calling the standard DMA mapping API. | |
583 | * | |
584 | * Returns: | |
585 | * A pointer to the scatter/gather table of pinned pages or NULL on failure. | |
586 | */ | |
587 | struct sg_table *drm_gem_shmem_get_sg_table(struct drm_gem_object *obj) | |
588 | { | |
589 | struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj); | |
590 | ||
591 | return drm_prime_pages_to_sg(shmem->pages, obj->size >> PAGE_SHIFT); | |
592 | } | |
593 | EXPORT_SYMBOL_GPL(drm_gem_shmem_get_sg_table); | |
594 | ||
595 | /** | |
596 | * drm_gem_shmem_get_pages_sgt - Pin pages, dma map them, and return a | |
597 | * scatter/gather table for a shmem GEM object. | |
598 | * @obj: GEM object | |
599 | * | |
600 | * This function returns a scatter/gather table suitable for driver usage. If | |
601 | * the sg table doesn't exist, the pages are pinned, dma-mapped, and a sg | |
602 | * table created. | |
603 | * | |
604 | * Returns: | |
605 | * A pointer to the scatter/gather table of pinned pages or errno on failure. | |
606 | */ | |
607 | struct sg_table *drm_gem_shmem_get_pages_sgt(struct drm_gem_object *obj) | |
608 | { | |
609 | int ret; | |
610 | struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj); | |
611 | struct sg_table *sgt; | |
612 | ||
613 | if (shmem->sgt) | |
614 | return shmem->sgt; | |
615 | ||
616 | WARN_ON(obj->import_attach); | |
617 | ||
618 | ret = drm_gem_shmem_get_pages(shmem); | |
619 | if (ret) | |
620 | return ERR_PTR(ret); | |
621 | ||
622 | sgt = drm_gem_shmem_get_sg_table(&shmem->base); | |
623 | if (IS_ERR(sgt)) { | |
624 | ret = PTR_ERR(sgt); | |
625 | goto err_put_pages; | |
626 | } | |
627 | /* Map the pages for use by the h/w. */ | |
628 | dma_map_sg(obj->dev->dev, sgt->sgl, sgt->nents, DMA_BIDIRECTIONAL); | |
629 | ||
630 | shmem->sgt = sgt; | |
631 | ||
632 | return sgt; | |
633 | ||
634 | err_put_pages: | |
635 | drm_gem_shmem_put_pages(shmem); | |
636 | return ERR_PTR(ret); | |
637 | } | |
638 | EXPORT_SYMBOL_GPL(drm_gem_shmem_get_pages_sgt); | |
639 | ||
640 | /** | |
641 | * drm_gem_shmem_prime_import_sg_table - Produce a shmem GEM object from | |
642 | * another driver's scatter/gather table of pinned pages | |
643 | * @dev: Device to import into | |
644 | * @attach: DMA-BUF attachment | |
645 | * @sgt: Scatter/gather table of pinned pages | |
646 | * | |
647 | * This function imports a scatter/gather table exported via DMA-BUF by | |
648 | * another driver. Drivers that use the shmem helpers should set this as their | |
649 | * &drm_driver.gem_prime_import_sg_table callback. | |
650 | * | |
651 | * Returns: | |
652 | * A pointer to a newly created GEM object or an ERR_PTR-encoded negative | |
653 | * error code on failure. | |
654 | */ | |
655 | struct drm_gem_object * | |
656 | drm_gem_shmem_prime_import_sg_table(struct drm_device *dev, | |
657 | struct dma_buf_attachment *attach, | |
658 | struct sg_table *sgt) | |
659 | { | |
660 | size_t size = PAGE_ALIGN(attach->dmabuf->size); | |
661 | size_t npages = size >> PAGE_SHIFT; | |
662 | struct drm_gem_shmem_object *shmem; | |
663 | int ret; | |
664 | ||
665 | shmem = drm_gem_shmem_create(dev, size); | |
666 | if (IS_ERR(shmem)) | |
667 | return ERR_CAST(shmem); | |
668 | ||
669 | shmem->pages = kvmalloc_array(npages, sizeof(struct page *), GFP_KERNEL); | |
670 | if (!shmem->pages) { | |
671 | ret = -ENOMEM; | |
672 | goto err_free_gem; | |
673 | } | |
674 | ||
675 | ret = drm_prime_sg_to_page_addr_arrays(sgt, shmem->pages, NULL, npages); | |
676 | if (ret < 0) | |
677 | goto err_free_array; | |
678 | ||
679 | shmem->sgt = sgt; | |
680 | shmem->pages_use_count = 1; /* Permanently pinned from our point of view */ | |
681 | ||
682 | DRM_DEBUG_PRIME("size = %zu\n", size); | |
683 | ||
684 | return &shmem->base; | |
685 | ||
686 | err_free_array: | |
687 | kvfree(shmem->pages); | |
688 | err_free_gem: | |
689 | drm_gem_object_put_unlocked(&shmem->base); | |
690 | ||
691 | return ERR_PTR(ret); | |
692 | } | |
693 | EXPORT_SYMBOL_GPL(drm_gem_shmem_prime_import_sg_table); |