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3248877e DA |
1 | /* |
2 | * Copyright © 2012 Red Hat | |
3 | * | |
4 | * Permission is hereby granted, free of charge, to any person obtaining a | |
5 | * copy of this software and associated documentation files (the "Software"), | |
6 | * to deal in the Software without restriction, including without limitation | |
7 | * the rights to use, copy, modify, merge, publish, distribute, sublicense, | |
8 | * and/or sell copies of the Software, and to permit persons to whom the | |
9 | * Software is furnished to do so, subject to the following conditions: | |
10 | * | |
11 | * The above copyright notice and this permission notice (including the next | |
12 | * paragraph) shall be included in all copies or substantial portions of the | |
13 | * Software. | |
14 | * | |
15 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR | |
16 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, | |
17 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL | |
18 | * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER | |
19 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING | |
20 | * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS | |
21 | * IN THE SOFTWARE. | |
22 | * | |
23 | * Authors: | |
24 | * Dave Airlie <airlied@redhat.com> | |
25 | * Rob Clark <rob.clark@linaro.org> | |
26 | * | |
27 | */ | |
28 | ||
29 | #include <linux/export.h> | |
30 | #include <linux/dma-buf.h> | |
077675c1 | 31 | #include <linux/rbtree.h> |
c6bb9baa | 32 | #include <drm/drm_prime.h> |
d9fc9413 | 33 | #include <drm/drm_gem.h> |
c6bb9baa | 34 | #include <drm/drmP.h> |
d9fc9413 | 35 | |
67d0ec4e | 36 | #include "drm_internal.h" |
3248877e DA |
37 | |
38 | /* | |
39 | * DMA-BUF/GEM Object references and lifetime overview: | |
40 | * | |
41 | * On the export the dma_buf holds a reference to the exporting GEM | |
42 | * object. It takes this reference in handle_to_fd_ioctl, when it | |
43 | * first calls .prime_export and stores the exporting GEM object in | |
fa4c1de4 OA |
44 | * the dma_buf priv. This reference needs to be released when the |
45 | * final reference to the &dma_buf itself is dropped and its | |
46 | * &dma_buf_ops.release function is called. For GEM-based drivers, | |
47 | * the dma_buf should be exported using drm_gem_dmabuf_export() and | |
48 | * then released by drm_gem_dmabuf_release(). | |
3248877e DA |
49 | * |
50 | * On the import the importing GEM object holds a reference to the | |
51 | * dma_buf (which in turn holds a ref to the exporting GEM object). | |
52 | * It takes that reference in the fd_to_handle ioctl. | |
53 | * It calls dma_buf_get, creates an attachment to it and stores the | |
54 | * attachment in the GEM object. When this attachment is destroyed | |
55 | * when the imported object is destroyed, we remove the attachment | |
56 | * and drop the reference to the dma_buf. | |
57 | * | |
fa4c1de4 OA |
58 | * When all the references to the &dma_buf are dropped, i.e. when |
59 | * userspace has closed both handles to the imported GEM object (through the | |
60 | * FD_TO_HANDLE IOCTL) and closed the file descriptor of the exported | |
61 | * (through the HANDLE_TO_FD IOCTL) dma_buf, and all kernel-internal references | |
62 | * are also gone, then the dma_buf gets destroyed. This can also happen as a | |
63 | * part of the clean up procedure in the drm_release() function if userspace | |
64 | * fails to properly clean up. Note that both the kernel and userspace (by | |
65 | * keeeping the PRIME file descriptors open) can hold references onto a | |
66 | * &dma_buf. | |
67 | * | |
3248877e DA |
68 | * Thus the chain of references always flows in one direction |
69 | * (avoiding loops): importing_gem -> dmabuf -> exporting_gem | |
70 | * | |
71 | * Self-importing: if userspace is using PRIME as a replacement for flink | |
72 | * then it will get a fd->handle request for a GEM object that it created. | |
73 | * Drivers should detect this situation and return back the gem object | |
89177644 AP |
74 | * from the dma-buf private. Prime will do this automatically for drivers that |
75 | * use the drm_gem_prime_{import,export} helpers. | |
f7a71b0c SL |
76 | * |
77 | * GEM struct &dma_buf_ops symbols are now exported. They can be resued by | |
78 | * drivers which implement GEM interface. | |
3248877e DA |
79 | */ |
80 | ||
81 | struct drm_prime_member { | |
3248877e DA |
82 | struct dma_buf *dma_buf; |
83 | uint32_t handle; | |
077675c1 CW |
84 | |
85 | struct rb_node dmabuf_rb; | |
86 | struct rb_node handle_rb; | |
3248877e | 87 | }; |
538d6661 JS |
88 | |
89 | struct drm_prime_attachment { | |
90 | struct sg_table *sgt; | |
91 | enum dma_data_direction dir; | |
92 | }; | |
93 | ||
39cc344a DV |
94 | static int drm_prime_add_buf_handle(struct drm_prime_file_private *prime_fpriv, |
95 | struct dma_buf *dma_buf, uint32_t handle) | |
ce92e3c9 SWK |
96 | { |
97 | struct drm_prime_member *member; | |
077675c1 | 98 | struct rb_node **p, *rb; |
ce92e3c9 SWK |
99 | |
100 | member = kmalloc(sizeof(*member), GFP_KERNEL); | |
101 | if (!member) | |
102 | return -ENOMEM; | |
103 | ||
104 | get_dma_buf(dma_buf); | |
105 | member->dma_buf = dma_buf; | |
106 | member->handle = handle; | |
077675c1 CW |
107 | |
108 | rb = NULL; | |
109 | p = &prime_fpriv->dmabufs.rb_node; | |
110 | while (*p) { | |
111 | struct drm_prime_member *pos; | |
112 | ||
113 | rb = *p; | |
114 | pos = rb_entry(rb, struct drm_prime_member, dmabuf_rb); | |
115 | if (dma_buf > pos->dma_buf) | |
116 | p = &rb->rb_right; | |
117 | else | |
118 | p = &rb->rb_left; | |
119 | } | |
120 | rb_link_node(&member->dmabuf_rb, rb, p); | |
121 | rb_insert_color(&member->dmabuf_rb, &prime_fpriv->dmabufs); | |
122 | ||
123 | rb = NULL; | |
124 | p = &prime_fpriv->handles.rb_node; | |
125 | while (*p) { | |
126 | struct drm_prime_member *pos; | |
127 | ||
128 | rb = *p; | |
129 | pos = rb_entry(rb, struct drm_prime_member, handle_rb); | |
130 | if (handle > pos->handle) | |
131 | p = &rb->rb_right; | |
132 | else | |
133 | p = &rb->rb_left; | |
134 | } | |
135 | rb_link_node(&member->handle_rb, rb, p); | |
136 | rb_insert_color(&member->handle_rb, &prime_fpriv->handles); | |
137 | ||
ce92e3c9 SWK |
138 | return 0; |
139 | } | |
3248877e | 140 | |
d0b2c533 DV |
141 | static struct dma_buf *drm_prime_lookup_buf_by_handle(struct drm_prime_file_private *prime_fpriv, |
142 | uint32_t handle) | |
143 | { | |
077675c1 CW |
144 | struct rb_node *rb; |
145 | ||
146 | rb = prime_fpriv->handles.rb_node; | |
147 | while (rb) { | |
148 | struct drm_prime_member *member; | |
d0b2c533 | 149 | |
077675c1 | 150 | member = rb_entry(rb, struct drm_prime_member, handle_rb); |
d0b2c533 DV |
151 | if (member->handle == handle) |
152 | return member->dma_buf; | |
077675c1 CW |
153 | else if (member->handle < handle) |
154 | rb = rb->rb_right; | |
155 | else | |
156 | rb = rb->rb_left; | |
d0b2c533 DV |
157 | } |
158 | ||
159 | return NULL; | |
160 | } | |
161 | ||
de9564d8 DV |
162 | static int drm_prime_lookup_buf_handle(struct drm_prime_file_private *prime_fpriv, |
163 | struct dma_buf *dma_buf, | |
164 | uint32_t *handle) | |
165 | { | |
077675c1 CW |
166 | struct rb_node *rb; |
167 | ||
168 | rb = prime_fpriv->dmabufs.rb_node; | |
169 | while (rb) { | |
170 | struct drm_prime_member *member; | |
de9564d8 | 171 | |
077675c1 | 172 | member = rb_entry(rb, struct drm_prime_member, dmabuf_rb); |
de9564d8 DV |
173 | if (member->dma_buf == dma_buf) { |
174 | *handle = member->handle; | |
175 | return 0; | |
077675c1 CW |
176 | } else if (member->dma_buf < dma_buf) { |
177 | rb = rb->rb_right; | |
178 | } else { | |
179 | rb = rb->rb_left; | |
de9564d8 DV |
180 | } |
181 | } | |
077675c1 | 182 | |
de9564d8 DV |
183 | return -ENOENT; |
184 | } | |
185 | ||
f7a71b0c SL |
186 | /** |
187 | * drm_gem_map_attach - dma_buf attach implementation for GEM | |
188 | * @dma_buf: buffer to attach device to | |
f7a71b0c SL |
189 | * @attach: buffer attachment data |
190 | * | |
191 | * Allocates &drm_prime_attachment and calls &drm_driver.gem_prime_pin for | |
192 | * device specific attachment. This can be used as the &dma_buf_ops.attach | |
193 | * callback. | |
194 | * | |
195 | * Returns 0 on success, negative error code on failure. | |
196 | */ | |
a19741e5 | 197 | int drm_gem_map_attach(struct dma_buf *dma_buf, |
c308279f | 198 | struct dma_buf_attachment *attach) |
ca793f75 | 199 | { |
538d6661 | 200 | struct drm_prime_attachment *prime_attach; |
ca793f75 ML |
201 | struct drm_gem_object *obj = dma_buf->priv; |
202 | struct drm_device *dev = obj->dev; | |
203 | ||
538d6661 JS |
204 | prime_attach = kzalloc(sizeof(*prime_attach), GFP_KERNEL); |
205 | if (!prime_attach) | |
206 | return -ENOMEM; | |
207 | ||
208 | prime_attach->dir = DMA_NONE; | |
209 | attach->priv = prime_attach; | |
210 | ||
ca793f75 ML |
211 | if (!dev->driver->gem_prime_pin) |
212 | return 0; | |
213 | ||
214 | return dev->driver->gem_prime_pin(obj); | |
215 | } | |
c308279f | 216 | EXPORT_SYMBOL(drm_gem_map_attach); |
ca793f75 | 217 | |
f7a71b0c SL |
218 | /** |
219 | * drm_gem_map_detach - dma_buf detach implementation for GEM | |
220 | * @dma_buf: buffer to detach from | |
221 | * @attach: attachment to be detached | |
222 | * | |
223 | * Cleans up &dma_buf_attachment. This can be used as the &dma_buf_ops.detach | |
224 | * callback. | |
225 | */ | |
c308279f SL |
226 | void drm_gem_map_detach(struct dma_buf *dma_buf, |
227 | struct dma_buf_attachment *attach) | |
ca793f75 | 228 | { |
538d6661 | 229 | struct drm_prime_attachment *prime_attach = attach->priv; |
ca793f75 ML |
230 | struct drm_gem_object *obj = dma_buf->priv; |
231 | struct drm_device *dev = obj->dev; | |
232 | ||
681066ec CK |
233 | if (prime_attach) { |
234 | struct sg_table *sgt = prime_attach->sgt; | |
538d6661 | 235 | |
681066ec CK |
236 | if (sgt) { |
237 | if (prime_attach->dir != DMA_NONE) | |
238 | dma_unmap_sg_attrs(attach->dev, sgt->sgl, | |
239 | sgt->nents, | |
240 | prime_attach->dir, | |
241 | DMA_ATTR_SKIP_CPU_SYNC); | |
242 | sg_free_table(sgt); | |
243 | } | |
244 | ||
245 | kfree(sgt); | |
246 | kfree(prime_attach); | |
247 | attach->priv = NULL; | |
f9d8a129 | 248 | } |
538d6661 | 249 | |
681066ec CK |
250 | if (dev->driver->gem_prime_unpin) |
251 | dev->driver->gem_prime_unpin(obj); | |
ca793f75 | 252 | } |
c308279f | 253 | EXPORT_SYMBOL(drm_gem_map_detach); |
ca793f75 | 254 | |
d0b2c533 DV |
255 | void drm_prime_remove_buf_handle_locked(struct drm_prime_file_private *prime_fpriv, |
256 | struct dma_buf *dma_buf) | |
da34242e | 257 | { |
077675c1 | 258 | struct rb_node *rb; |
da34242e | 259 | |
077675c1 CW |
260 | rb = prime_fpriv->dmabufs.rb_node; |
261 | while (rb) { | |
262 | struct drm_prime_member *member; | |
263 | ||
264 | member = rb_entry(rb, struct drm_prime_member, dmabuf_rb); | |
da34242e | 265 | if (member->dma_buf == dma_buf) { |
077675c1 CW |
266 | rb_erase(&member->handle_rb, &prime_fpriv->handles); |
267 | rb_erase(&member->dmabuf_rb, &prime_fpriv->dmabufs); | |
268 | ||
da34242e | 269 | dma_buf_put(dma_buf); |
da34242e | 270 | kfree(member); |
077675c1 CW |
271 | return; |
272 | } else if (member->dma_buf < dma_buf) { | |
273 | rb = rb->rb_right; | |
274 | } else { | |
275 | rb = rb->rb_left; | |
da34242e YC |
276 | } |
277 | } | |
278 | } | |
279 | ||
f7a71b0c SL |
280 | /** |
281 | * drm_gem_map_dma_buf - map_dma_buf implementation for GEM | |
282 | * @attach: attachment whose scatterlist is to be returned | |
283 | * @dir: direction of DMA transfer | |
284 | * | |
285 | * Calls &drm_driver.gem_prime_get_sg_table and then maps the scatterlist. This | |
286 | * can be used as the &dma_buf_ops.map_dma_buf callback. | |
287 | * | |
288 | * Returns sg_table containing the scatterlist to be returned; returns ERR_PTR | |
289 | * on error. May return -EINTR if it is interrupted by a signal. | |
290 | */ | |
291 | ||
c308279f SL |
292 | struct sg_table *drm_gem_map_dma_buf(struct dma_buf_attachment *attach, |
293 | enum dma_data_direction dir) | |
89177644 | 294 | { |
538d6661 | 295 | struct drm_prime_attachment *prime_attach = attach->priv; |
89177644 AP |
296 | struct drm_gem_object *obj = attach->dmabuf->priv; |
297 | struct sg_table *sgt; | |
298 | ||
538d6661 JS |
299 | if (WARN_ON(dir == DMA_NONE || !prime_attach)) |
300 | return ERR_PTR(-EINVAL); | |
301 | ||
302 | /* return the cached mapping when possible */ | |
303 | if (prime_attach->dir == dir) | |
304 | return prime_attach->sgt; | |
305 | ||
306 | /* | |
307 | * two mappings with different directions for the same attachment are | |
308 | * not allowed | |
309 | */ | |
310 | if (WARN_ON(prime_attach->dir != DMA_NONE)) | |
311 | return ERR_PTR(-EBUSY); | |
312 | ||
89177644 AP |
313 | sgt = obj->dev->driver->gem_prime_get_sg_table(obj); |
314 | ||
7e3d88f9 | 315 | if (!IS_ERR(sgt)) { |
ca0e68e2 LS |
316 | if (!dma_map_sg_attrs(attach->dev, sgt->sgl, sgt->nents, dir, |
317 | DMA_ATTR_SKIP_CPU_SYNC)) { | |
b720d54a YC |
318 | sg_free_table(sgt); |
319 | kfree(sgt); | |
320 | sgt = ERR_PTR(-ENOMEM); | |
538d6661 JS |
321 | } else { |
322 | prime_attach->sgt = sgt; | |
323 | prime_attach->dir = dir; | |
b720d54a YC |
324 | } |
325 | } | |
89177644 | 326 | |
89177644 AP |
327 | return sgt; |
328 | } | |
c308279f | 329 | EXPORT_SYMBOL(drm_gem_map_dma_buf); |
89177644 | 330 | |
f7a71b0c SL |
331 | /** |
332 | * drm_gem_unmap_dma_buf - unmap_dma_buf implementation for GEM | |
790861cc SL |
333 | * @attach: attachment to unmap buffer from |
334 | * @sgt: scatterlist info of the buffer to unmap | |
335 | * @dir: direction of DMA transfer | |
f7a71b0c SL |
336 | * |
337 | * Not implemented. The unmap is done at drm_gem_map_detach(). This can be | |
338 | * used as the &dma_buf_ops.unmap_dma_buf callback. | |
339 | */ | |
c308279f SL |
340 | void drm_gem_unmap_dma_buf(struct dma_buf_attachment *attach, |
341 | struct sg_table *sgt, | |
342 | enum dma_data_direction dir) | |
89177644 | 343 | { |
538d6661 | 344 | /* nothing to be done here */ |
89177644 | 345 | } |
c308279f | 346 | EXPORT_SYMBOL(drm_gem_unmap_dma_buf); |
89177644 | 347 | |
a4fce9cb CW |
348 | /** |
349 | * drm_gem_dmabuf_export - dma_buf export implementation for GEM | |
67c8f116 CW |
350 | * @dev: parent device for the exported dmabuf |
351 | * @exp_info: the export information used by dma_buf_export() | |
a4fce9cb CW |
352 | * |
353 | * This wraps dma_buf_export() for use by generic GEM drivers that are using | |
354 | * drm_gem_dmabuf_release(). In addition to calling dma_buf_export(), we take | |
72a93e8d | 355 | * a reference to the &drm_device and the exported &drm_gem_object (stored in |
940eba2d | 356 | * &dma_buf_export_info.priv) which is released by drm_gem_dmabuf_release(). |
a4fce9cb CW |
357 | * |
358 | * Returns the new dmabuf. | |
359 | */ | |
360 | struct dma_buf *drm_gem_dmabuf_export(struct drm_device *dev, | |
361 | struct dma_buf_export_info *exp_info) | |
362 | { | |
363 | struct dma_buf *dma_buf; | |
364 | ||
365 | dma_buf = dma_buf_export(exp_info); | |
72a93e8d CW |
366 | if (IS_ERR(dma_buf)) |
367 | return dma_buf; | |
368 | ||
9a96f550 | 369 | drm_dev_get(dev); |
e6b62714 | 370 | drm_gem_object_get(exp_info->priv); |
a4fce9cb CW |
371 | |
372 | return dma_buf; | |
373 | } | |
374 | EXPORT_SYMBOL(drm_gem_dmabuf_export); | |
375 | ||
39cc344a DV |
376 | /** |
377 | * drm_gem_dmabuf_release - dma_buf release implementation for GEM | |
378 | * @dma_buf: buffer to be released | |
379 | * | |
380 | * Generic release function for dma_bufs exported as PRIME buffers. GEM drivers | |
381 | * must use this in their dma_buf ops structure as the release callback. | |
a4fce9cb CW |
382 | * drm_gem_dmabuf_release() should be used in conjunction with |
383 | * drm_gem_dmabuf_export(). | |
39cc344a | 384 | */ |
c1d6798d | 385 | void drm_gem_dmabuf_release(struct dma_buf *dma_buf) |
89177644 AP |
386 | { |
387 | struct drm_gem_object *obj = dma_buf->priv; | |
a4fce9cb | 388 | struct drm_device *dev = obj->dev; |
89177644 | 389 | |
319c933c | 390 | /* drop the reference on the export fd holds */ |
e6b62714 | 391 | drm_gem_object_put_unlocked(obj); |
a4fce9cb | 392 | |
ffeeeed0 | 393 | drm_dev_put(dev); |
89177644 | 394 | } |
c1d6798d | 395 | EXPORT_SYMBOL(drm_gem_dmabuf_release); |
89177644 | 396 | |
f7a71b0c SL |
397 | /** |
398 | * drm_gem_dmabuf_vmap - dma_buf vmap implementation for GEM | |
399 | * @dma_buf: buffer to be mapped | |
400 | * | |
401 | * Sets up a kernel virtual mapping. This can be used as the &dma_buf_ops.vmap | |
402 | * callback. | |
403 | * | |
404 | * Returns the kernel virtual address. | |
405 | */ | |
c308279f | 406 | void *drm_gem_dmabuf_vmap(struct dma_buf *dma_buf) |
89177644 AP |
407 | { |
408 | struct drm_gem_object *obj = dma_buf->priv; | |
409 | struct drm_device *dev = obj->dev; | |
410 | ||
d34deab9 EA |
411 | if (dev->driver->gem_prime_vmap) |
412 | return dev->driver->gem_prime_vmap(obj); | |
413 | else | |
414 | return NULL; | |
89177644 | 415 | } |
c308279f | 416 | EXPORT_SYMBOL(drm_gem_dmabuf_vmap); |
89177644 | 417 | |
f7a71b0c SL |
418 | /** |
419 | * drm_gem_dmabuf_vunmap - dma_buf vunmap implementation for GEM | |
420 | * @dma_buf: buffer to be unmapped | |
421 | * @vaddr: the virtual address of the buffer | |
422 | * | |
423 | * Releases a kernel virtual mapping. This can be used as the | |
424 | * &dma_buf_ops.vunmap callback. | |
425 | */ | |
c308279f | 426 | void drm_gem_dmabuf_vunmap(struct dma_buf *dma_buf, void *vaddr) |
89177644 AP |
427 | { |
428 | struct drm_gem_object *obj = dma_buf->priv; | |
429 | struct drm_device *dev = obj->dev; | |
430 | ||
d34deab9 EA |
431 | if (dev->driver->gem_prime_vunmap) |
432 | dev->driver->gem_prime_vunmap(obj, vaddr); | |
89177644 | 433 | } |
c308279f | 434 | EXPORT_SYMBOL(drm_gem_dmabuf_vunmap); |
89177644 | 435 | |
f7a71b0c SL |
436 | /** |
437 | * drm_gem_dmabuf_mmap - dma_buf mmap implementation for GEM | |
438 | * @dma_buf: buffer to be mapped | |
439 | * @vma: virtual address range | |
440 | * | |
441 | * Provides memory mapping for the buffer. This can be used as the | |
442 | * &dma_buf_ops.mmap callback. | |
443 | * | |
444 | * Returns 0 on success or a negative error code on failure. | |
445 | */ | |
c308279f | 446 | int drm_gem_dmabuf_mmap(struct dma_buf *dma_buf, struct vm_area_struct *vma) |
89177644 | 447 | { |
7c397cd9 JS |
448 | struct drm_gem_object *obj = dma_buf->priv; |
449 | struct drm_device *dev = obj->dev; | |
450 | ||
451 | if (!dev->driver->gem_prime_mmap) | |
452 | return -ENOSYS; | |
453 | ||
454 | return dev->driver->gem_prime_mmap(obj, vma); | |
89177644 | 455 | } |
c308279f | 456 | EXPORT_SYMBOL(drm_gem_dmabuf_mmap); |
89177644 AP |
457 | |
458 | static const struct dma_buf_ops drm_gem_prime_dmabuf_ops = { | |
ca793f75 ML |
459 | .attach = drm_gem_map_attach, |
460 | .detach = drm_gem_map_detach, | |
89177644 AP |
461 | .map_dma_buf = drm_gem_map_dma_buf, |
462 | .unmap_dma_buf = drm_gem_unmap_dma_buf, | |
463 | .release = drm_gem_dmabuf_release, | |
89177644 AP |
464 | .mmap = drm_gem_dmabuf_mmap, |
465 | .vmap = drm_gem_dmabuf_vmap, | |
466 | .vunmap = drm_gem_dmabuf_vunmap, | |
467 | }; | |
468 | ||
469 | /** | |
470 | * DOC: PRIME Helpers | |
471 | * | |
472 | * Drivers can implement @gem_prime_export and @gem_prime_import in terms of | |
473 | * simpler APIs by using the helper functions @drm_gem_prime_export and | |
474 | * @drm_gem_prime_import. These functions implement dma-buf support in terms of | |
ffc5fbdb | 475 | * six lower-level driver callbacks: |
89177644 AP |
476 | * |
477 | * Export callbacks: | |
478 | * | |
f03d8ede DCLP |
479 | * * @gem_prime_pin (optional): prepare a GEM object for exporting |
480 | * * @gem_prime_get_sg_table: provide a scatter/gather table of pinned pages | |
481 | * * @gem_prime_vmap: vmap a buffer exported by your driver | |
482 | * * @gem_prime_vunmap: vunmap a buffer exported by your driver | |
483 | * * @gem_prime_mmap (optional): mmap a buffer exported by your driver | |
ffc5fbdb | 484 | * |
89177644 AP |
485 | * Import callback: |
486 | * | |
f03d8ede | 487 | * * @gem_prime_import_sg_table (import): produce a GEM object from another |
89177644 AP |
488 | * driver's scatter/gather table |
489 | */ | |
490 | ||
39cc344a | 491 | /** |
32197aab | 492 | * drm_gem_prime_export - helper library implementation of the export callback |
39cc344a DV |
493 | * @dev: drm_device to export from |
494 | * @obj: GEM object to export | |
bfe981a0 | 495 | * @flags: flags like DRM_CLOEXEC and DRM_RDWR |
39cc344a DV |
496 | * |
497 | * This is the implementation of the gem_prime_export functions for GEM drivers | |
498 | * using the PRIME helpers. | |
499 | */ | |
89177644 | 500 | struct dma_buf *drm_gem_prime_export(struct drm_device *dev, |
56a76c01 CW |
501 | struct drm_gem_object *obj, |
502 | int flags) | |
89177644 | 503 | { |
56a76c01 CW |
504 | struct dma_buf_export_info exp_info = { |
505 | .exp_name = KBUILD_MODNAME, /* white lie for debug */ | |
506 | .owner = dev->driver->fops->owner, | |
507 | .ops = &drm_gem_prime_dmabuf_ops, | |
508 | .size = obj->size, | |
509 | .flags = flags, | |
510 | .priv = obj, | |
511 | }; | |
3aac4502 ML |
512 | |
513 | if (dev->driver->gem_prime_res_obj) | |
d8fbe341 | 514 | exp_info.resv = dev->driver->gem_prime_res_obj(obj); |
3aac4502 | 515 | |
a4fce9cb | 516 | return drm_gem_dmabuf_export(dev, &exp_info); |
89177644 AP |
517 | } |
518 | EXPORT_SYMBOL(drm_gem_prime_export); | |
519 | ||
319c933c DV |
520 | static struct dma_buf *export_and_register_object(struct drm_device *dev, |
521 | struct drm_gem_object *obj, | |
522 | uint32_t flags) | |
523 | { | |
524 | struct dma_buf *dmabuf; | |
525 | ||
526 | /* prevent races with concurrent gem_close. */ | |
527 | if (obj->handle_count == 0) { | |
528 | dmabuf = ERR_PTR(-ENOENT); | |
529 | return dmabuf; | |
530 | } | |
531 | ||
532 | dmabuf = dev->driver->gem_prime_export(dev, obj, flags); | |
533 | if (IS_ERR(dmabuf)) { | |
534 | /* normally the created dma-buf takes ownership of the ref, | |
535 | * but if that fails then drop the ref | |
536 | */ | |
537 | return dmabuf; | |
538 | } | |
539 | ||
540 | /* | |
541 | * Note that callers do not need to clean up the export cache | |
542 | * since the check for obj->handle_count guarantees that someone | |
543 | * will clean it up. | |
544 | */ | |
545 | obj->dma_buf = dmabuf; | |
546 | get_dma_buf(obj->dma_buf); | |
547 | ||
548 | return dmabuf; | |
549 | } | |
550 | ||
39cc344a DV |
551 | /** |
552 | * drm_gem_prime_handle_to_fd - PRIME export function for GEM drivers | |
553 | * @dev: dev to export the buffer from | |
554 | * @file_priv: drm file-private structure | |
555 | * @handle: buffer handle to export | |
556 | * @flags: flags like DRM_CLOEXEC | |
557 | * @prime_fd: pointer to storage for the fd id of the create dma-buf | |
558 | * | |
559 | * This is the PRIME export function which must be used mandatorily by GEM | |
560 | * drivers to ensure correct lifetime management of the underlying GEM object. | |
561 | * The actual exporting from GEM object to a dma-buf is done through the | |
562 | * gem_prime_export driver callback. | |
563 | */ | |
3248877e | 564 | int drm_gem_prime_handle_to_fd(struct drm_device *dev, |
39cc344a DV |
565 | struct drm_file *file_priv, uint32_t handle, |
566 | uint32_t flags, | |
567 | int *prime_fd) | |
3248877e DA |
568 | { |
569 | struct drm_gem_object *obj; | |
219b4733 DA |
570 | int ret = 0; |
571 | struct dma_buf *dmabuf; | |
3248877e | 572 | |
d0b2c533 | 573 | mutex_lock(&file_priv->prime.lock); |
a8ad0bd8 | 574 | obj = drm_gem_object_lookup(file_priv, handle); |
d0b2c533 DV |
575 | if (!obj) { |
576 | ret = -ENOENT; | |
577 | goto out_unlock; | |
578 | } | |
579 | ||
580 | dmabuf = drm_prime_lookup_buf_by_handle(&file_priv->prime, handle); | |
581 | if (dmabuf) { | |
582 | get_dma_buf(dmabuf); | |
583 | goto out_have_handle; | |
584 | } | |
3248877e | 585 | |
d0b2c533 | 586 | mutex_lock(&dev->object_name_lock); |
3248877e DA |
587 | /* re-export the original imported object */ |
588 | if (obj->import_attach) { | |
219b4733 | 589 | dmabuf = obj->import_attach->dmabuf; |
319c933c | 590 | get_dma_buf(dmabuf); |
219b4733 | 591 | goto out_have_obj; |
3248877e DA |
592 | } |
593 | ||
319c933c DV |
594 | if (obj->dma_buf) { |
595 | get_dma_buf(obj->dma_buf); | |
596 | dmabuf = obj->dma_buf; | |
219b4733 | 597 | goto out_have_obj; |
3248877e | 598 | } |
219b4733 | 599 | |
319c933c | 600 | dmabuf = export_and_register_object(dev, obj, flags); |
4332bf43 | 601 | if (IS_ERR(dmabuf)) { |
219b4733 DA |
602 | /* normally the created dma-buf takes ownership of the ref, |
603 | * but if that fails then drop the ref | |
604 | */ | |
4332bf43 | 605 | ret = PTR_ERR(dmabuf); |
d0b2c533 | 606 | mutex_unlock(&dev->object_name_lock); |
219b4733 DA |
607 | goto out; |
608 | } | |
219b4733 | 609 | |
d0b2c533 DV |
610 | out_have_obj: |
611 | /* | |
612 | * If we've exported this buffer then cheat and add it to the import list | |
613 | * so we get the correct handle back. We must do this under the | |
614 | * protection of dev->object_name_lock to ensure that a racing gem close | |
615 | * ioctl doesn't miss to remove this buffer handle from the cache. | |
0ff926c7 | 616 | */ |
219b4733 | 617 | ret = drm_prime_add_buf_handle(&file_priv->prime, |
319c933c | 618 | dmabuf, handle); |
d0b2c533 | 619 | mutex_unlock(&dev->object_name_lock); |
219b4733 | 620 | if (ret) |
7d8f06ac | 621 | goto fail_put_dmabuf; |
0ff926c7 | 622 | |
d0b2c533 | 623 | out_have_handle: |
4332bf43 | 624 | ret = dma_buf_fd(dmabuf, flags); |
d0b2c533 DV |
625 | /* |
626 | * We must _not_ remove the buffer from the handle cache since the newly | |
627 | * created dma buf is already linked in the global obj->dma_buf pointer, | |
628 | * and that is invariant as long as a userspace gem handle exists. | |
629 | * Closing the handle will clean out the cache anyway, so we don't leak. | |
630 | */ | |
4a88f73f | 631 | if (ret < 0) { |
d0b2c533 | 632 | goto fail_put_dmabuf; |
4a88f73f | 633 | } else { |
da34242e | 634 | *prime_fd = ret; |
4a88f73f DV |
635 | ret = 0; |
636 | } | |
637 | ||
7d8f06ac YC |
638 | goto out; |
639 | ||
640 | fail_put_dmabuf: | |
4332bf43 | 641 | dma_buf_put(dmabuf); |
219b4733 | 642 | out: |
e6b62714 | 643 | drm_gem_object_put_unlocked(obj); |
d0b2c533 DV |
644 | out_unlock: |
645 | mutex_unlock(&file_priv->prime.lock); | |
646 | ||
219b4733 | 647 | return ret; |
3248877e DA |
648 | } |
649 | EXPORT_SYMBOL(drm_gem_prime_handle_to_fd); | |
650 | ||
39cc344a | 651 | /** |
7e491583 | 652 | * drm_gem_prime_import_dev - core implementation of the import callback |
39cc344a DV |
653 | * @dev: drm_device to import into |
654 | * @dma_buf: dma-buf object to import | |
7e491583 | 655 | * @attach_dev: struct device to dma_buf attach |
39cc344a | 656 | * |
7e491583 LA |
657 | * This is the core of drm_gem_prime_import. It's designed to be called by |
658 | * drivers who want to use a different device structure than dev->dev for | |
659 | * attaching via dma_buf. | |
39cc344a | 660 | */ |
7e491583 LA |
661 | struct drm_gem_object *drm_gem_prime_import_dev(struct drm_device *dev, |
662 | struct dma_buf *dma_buf, | |
663 | struct device *attach_dev) | |
89177644 AP |
664 | { |
665 | struct dma_buf_attachment *attach; | |
666 | struct sg_table *sgt; | |
667 | struct drm_gem_object *obj; | |
668 | int ret; | |
669 | ||
89177644 AP |
670 | if (dma_buf->ops == &drm_gem_prime_dmabuf_ops) { |
671 | obj = dma_buf->priv; | |
672 | if (obj->dev == dev) { | |
673 | /* | |
674 | * Importing dmabuf exported from out own gem increases | |
675 | * refcount on gem itself instead of f_count of dmabuf. | |
676 | */ | |
e6b62714 | 677 | drm_gem_object_get(obj); |
89177644 AP |
678 | return obj; |
679 | } | |
680 | } | |
681 | ||
98515035 TF |
682 | if (!dev->driver->gem_prime_import_sg_table) |
683 | return ERR_PTR(-EINVAL); | |
684 | ||
7e491583 | 685 | attach = dma_buf_attach(dma_buf, attach_dev); |
89177644 | 686 | if (IS_ERR(attach)) |
f2a5da4f | 687 | return ERR_CAST(attach); |
89177644 | 688 | |
011c2282 ID |
689 | get_dma_buf(dma_buf); |
690 | ||
89177644 | 691 | sgt = dma_buf_map_attachment(attach, DMA_BIDIRECTIONAL); |
fee0c54e | 692 | if (IS_ERR(sgt)) { |
89177644 AP |
693 | ret = PTR_ERR(sgt); |
694 | goto fail_detach; | |
695 | } | |
696 | ||
b5e9c1a2 | 697 | obj = dev->driver->gem_prime_import_sg_table(dev, attach, sgt); |
89177644 AP |
698 | if (IS_ERR(obj)) { |
699 | ret = PTR_ERR(obj); | |
700 | goto fail_unmap; | |
701 | } | |
702 | ||
703 | obj->import_attach = attach; | |
704 | ||
705 | return obj; | |
706 | ||
707 | fail_unmap: | |
708 | dma_buf_unmap_attachment(attach, sgt, DMA_BIDIRECTIONAL); | |
709 | fail_detach: | |
710 | dma_buf_detach(dma_buf, attach); | |
011c2282 ID |
711 | dma_buf_put(dma_buf); |
712 | ||
89177644 AP |
713 | return ERR_PTR(ret); |
714 | } | |
7e491583 LA |
715 | EXPORT_SYMBOL(drm_gem_prime_import_dev); |
716 | ||
717 | /** | |
718 | * drm_gem_prime_import - helper library implementation of the import callback | |
719 | * @dev: drm_device to import into | |
720 | * @dma_buf: dma-buf object to import | |
721 | * | |
722 | * This is the implementation of the gem_prime_import functions for GEM drivers | |
723 | * using the PRIME helpers. | |
724 | */ | |
725 | struct drm_gem_object *drm_gem_prime_import(struct drm_device *dev, | |
726 | struct dma_buf *dma_buf) | |
727 | { | |
728 | return drm_gem_prime_import_dev(dev, dma_buf, dev->dev); | |
729 | } | |
89177644 AP |
730 | EXPORT_SYMBOL(drm_gem_prime_import); |
731 | ||
39cc344a DV |
732 | /** |
733 | * drm_gem_prime_fd_to_handle - PRIME import function for GEM drivers | |
734 | * @dev: dev to export the buffer from | |
735 | * @file_priv: drm file-private structure | |
736 | * @prime_fd: fd id of the dma-buf which should be imported | |
737 | * @handle: pointer to storage for the handle of the imported buffer object | |
738 | * | |
739 | * This is the PRIME import function which must be used mandatorily by GEM | |
740 | * drivers to ensure correct lifetime management of the underlying GEM object. | |
741 | * The actual importing of GEM object from the dma-buf is done through the | |
742 | * gem_import_export driver callback. | |
743 | */ | |
3248877e | 744 | int drm_gem_prime_fd_to_handle(struct drm_device *dev, |
39cc344a DV |
745 | struct drm_file *file_priv, int prime_fd, |
746 | uint32_t *handle) | |
3248877e DA |
747 | { |
748 | struct dma_buf *dma_buf; | |
749 | struct drm_gem_object *obj; | |
750 | int ret; | |
751 | ||
752 | dma_buf = dma_buf_get(prime_fd); | |
753 | if (IS_ERR(dma_buf)) | |
754 | return PTR_ERR(dma_buf); | |
755 | ||
756 | mutex_lock(&file_priv->prime.lock); | |
757 | ||
219b4733 | 758 | ret = drm_prime_lookup_buf_handle(&file_priv->prime, |
3248877e | 759 | dma_buf, handle); |
84341c28 | 760 | if (ret == 0) |
3248877e | 761 | goto out_put; |
3248877e DA |
762 | |
763 | /* never seen this one, need to import */ | |
319c933c | 764 | mutex_lock(&dev->object_name_lock); |
3248877e DA |
765 | obj = dev->driver->gem_prime_import(dev, dma_buf); |
766 | if (IS_ERR(obj)) { | |
767 | ret = PTR_ERR(obj); | |
319c933c DV |
768 | goto out_unlock; |
769 | } | |
770 | ||
771 | if (obj->dma_buf) { | |
772 | WARN_ON(obj->dma_buf != dma_buf); | |
773 | } else { | |
774 | obj->dma_buf = dma_buf; | |
775 | get_dma_buf(dma_buf); | |
3248877e DA |
776 | } |
777 | ||
bd6e2732 | 778 | /* _handle_create_tail unconditionally unlocks dev->object_name_lock. */ |
319c933c | 779 | ret = drm_gem_handle_create_tail(file_priv, obj, handle); |
e6b62714 | 780 | drm_gem_object_put_unlocked(obj); |
3248877e DA |
781 | if (ret) |
782 | goto out_put; | |
783 | ||
219b4733 | 784 | ret = drm_prime_add_buf_handle(&file_priv->prime, |
3248877e | 785 | dma_buf, *handle); |
bd6e2732 | 786 | mutex_unlock(&file_priv->prime.lock); |
3248877e DA |
787 | if (ret) |
788 | goto fail; | |
789 | ||
011c2282 ID |
790 | dma_buf_put(dma_buf); |
791 | ||
3248877e DA |
792 | return 0; |
793 | ||
794 | fail: | |
795 | /* hmm, if driver attached, we are relying on the free-object path | |
796 | * to detach.. which seems ok.. | |
797 | */ | |
730c4ff9 | 798 | drm_gem_handle_delete(file_priv, *handle); |
bd6e2732 RC |
799 | dma_buf_put(dma_buf); |
800 | return ret; | |
801 | ||
319c933c | 802 | out_unlock: |
0adb2370 | 803 | mutex_unlock(&dev->object_name_lock); |
3248877e | 804 | out_put: |
3248877e | 805 | mutex_unlock(&file_priv->prime.lock); |
bd6e2732 | 806 | dma_buf_put(dma_buf); |
3248877e DA |
807 | return ret; |
808 | } | |
809 | EXPORT_SYMBOL(drm_gem_prime_fd_to_handle); | |
810 | ||
811 | int drm_prime_handle_to_fd_ioctl(struct drm_device *dev, void *data, | |
812 | struct drm_file *file_priv) | |
813 | { | |
814 | struct drm_prime_handle *args = data; | |
3248877e DA |
815 | |
816 | if (!drm_core_check_feature(dev, DRIVER_PRIME)) | |
69fdf420 | 817 | return -EOPNOTSUPP; |
3248877e DA |
818 | |
819 | if (!dev->driver->prime_handle_to_fd) | |
820 | return -ENOSYS; | |
821 | ||
822 | /* check flags are valid */ | |
bfe981a0 | 823 | if (args->flags & ~(DRM_CLOEXEC | DRM_RDWR)) |
3248877e DA |
824 | return -EINVAL; |
825 | ||
3248877e | 826 | return dev->driver->prime_handle_to_fd(dev, file_priv, |
bfe981a0 | 827 | args->handle, args->flags, &args->fd); |
3248877e DA |
828 | } |
829 | ||
830 | int drm_prime_fd_to_handle_ioctl(struct drm_device *dev, void *data, | |
831 | struct drm_file *file_priv) | |
832 | { | |
833 | struct drm_prime_handle *args = data; | |
834 | ||
835 | if (!drm_core_check_feature(dev, DRIVER_PRIME)) | |
69fdf420 | 836 | return -EOPNOTSUPP; |
3248877e DA |
837 | |
838 | if (!dev->driver->prime_fd_to_handle) | |
839 | return -ENOSYS; | |
840 | ||
841 | return dev->driver->prime_fd_to_handle(dev, file_priv, | |
842 | args->fd, &args->handle); | |
843 | } | |
844 | ||
39cc344a DV |
845 | /** |
846 | * drm_prime_pages_to_sg - converts a page array into an sg list | |
847 | * @pages: pointer to the array of page pointers to convert | |
848 | * @nr_pages: length of the page vector | |
3248877e | 849 | * |
39cc344a | 850 | * This helper creates an sg table object from a set of pages |
3248877e | 851 | * the driver is responsible for mapping the pages into the |
39cc344a | 852 | * importers address space for use with dma_buf itself. |
3248877e | 853 | */ |
34eab43e | 854 | struct sg_table *drm_prime_pages_to_sg(struct page **pages, unsigned int nr_pages) |
3248877e DA |
855 | { |
856 | struct sg_table *sg = NULL; | |
3248877e DA |
857 | int ret; |
858 | ||
859 | sg = kmalloc(sizeof(struct sg_table), GFP_KERNEL); | |
7e3d88f9 YC |
860 | if (!sg) { |
861 | ret = -ENOMEM; | |
3248877e | 862 | goto out; |
7e3d88f9 | 863 | } |
3248877e | 864 | |
dca25cb8 RS |
865 | ret = sg_alloc_table_from_pages(sg, pages, nr_pages, 0, |
866 | nr_pages << PAGE_SHIFT, GFP_KERNEL); | |
3248877e DA |
867 | if (ret) |
868 | goto out; | |
869 | ||
3248877e DA |
870 | return sg; |
871 | out: | |
872 | kfree(sg); | |
7e3d88f9 | 873 | return ERR_PTR(ret); |
3248877e DA |
874 | } |
875 | EXPORT_SYMBOL(drm_prime_pages_to_sg); | |
876 | ||
39cc344a DV |
877 | /** |
878 | * drm_prime_sg_to_page_addr_arrays - convert an sg table into a page array | |
879 | * @sgt: scatter-gather table to convert | |
186ca446 | 880 | * @pages: optional array of page pointers to store the page array in |
39cc344a | 881 | * @addrs: optional array to store the dma bus address of each page |
186ca446 | 882 | * @max_entries: size of both the passed-in arrays |
39cc344a DV |
883 | * |
884 | * Exports an sg table into an array of pages and addresses. This is currently | |
885 | * required by the TTM driver in order to do correct fault handling. | |
886 | */ | |
51ab7ba2 | 887 | int drm_prime_sg_to_page_addr_arrays(struct sg_table *sgt, struct page **pages, |
186ca446 | 888 | dma_addr_t *addrs, int max_entries) |
51ab7ba2 DA |
889 | { |
890 | unsigned count; | |
891 | struct scatterlist *sg; | |
892 | struct page *page; | |
186ca446 | 893 | u32 len, index; |
51ab7ba2 DA |
894 | dma_addr_t addr; |
895 | ||
186ca446 | 896 | index = 0; |
51ab7ba2 DA |
897 | for_each_sg(sgt->sgl, sg, sgt->nents, count) { |
898 | len = sg->length; | |
51ab7ba2 DA |
899 | page = sg_page(sg); |
900 | addr = sg_dma_address(sg); | |
901 | ||
902 | while (len > 0) { | |
186ca446 | 903 | if (WARN_ON(index >= max_entries)) |
51ab7ba2 | 904 | return -1; |
186ca446 CK |
905 | if (pages) |
906 | pages[index] = page; | |
51ab7ba2 | 907 | if (addrs) |
186ca446 | 908 | addrs[index] = addr; |
51ab7ba2 DA |
909 | |
910 | page++; | |
911 | addr += PAGE_SIZE; | |
912 | len -= PAGE_SIZE; | |
186ca446 | 913 | index++; |
51ab7ba2 DA |
914 | } |
915 | } | |
916 | return 0; | |
917 | } | |
918 | EXPORT_SYMBOL(drm_prime_sg_to_page_addr_arrays); | |
39cc344a DV |
919 | |
920 | /** | |
921 | * drm_prime_gem_destroy - helper to clean up a PRIME-imported GEM object | |
922 | * @obj: GEM object which was created from a dma-buf | |
923 | * @sg: the sg-table which was pinned at import time | |
924 | * | |
925 | * This is the cleanup functions which GEM drivers need to call when they use | |
926 | * @drm_gem_prime_import to import dma-bufs. | |
927 | */ | |
3248877e DA |
928 | void drm_prime_gem_destroy(struct drm_gem_object *obj, struct sg_table *sg) |
929 | { | |
930 | struct dma_buf_attachment *attach; | |
931 | struct dma_buf *dma_buf; | |
932 | attach = obj->import_attach; | |
933 | if (sg) | |
934 | dma_buf_unmap_attachment(attach, sg, DMA_BIDIRECTIONAL); | |
935 | dma_buf = attach->dmabuf; | |
936 | dma_buf_detach(attach->dmabuf, attach); | |
937 | /* remove the reference */ | |
938 | dma_buf_put(dma_buf); | |
939 | } | |
940 | EXPORT_SYMBOL(drm_prime_gem_destroy); | |
941 | ||
942 | void drm_prime_init_file_private(struct drm_prime_file_private *prime_fpriv) | |
943 | { | |
3248877e | 944 | mutex_init(&prime_fpriv->lock); |
077675c1 CW |
945 | prime_fpriv->dmabufs = RB_ROOT; |
946 | prime_fpriv->handles = RB_ROOT; | |
3248877e | 947 | } |
3248877e DA |
948 | |
949 | void drm_prime_destroy_file_private(struct drm_prime_file_private *prime_fpriv) | |
950 | { | |
98b76231 | 951 | /* by now drm_gem_release should've made sure the list is empty */ |
077675c1 | 952 | WARN_ON(!RB_EMPTY_ROOT(&prime_fpriv->dmabufs)); |
3248877e | 953 | } |