xref: /freebsd/sys/dev/drm2/drm_gem.c (revision 2a3e3873a1e4cd958f2b0f85d3b10cfa40575d30)
1 /*-
2  * Copyright (c) 2011 The FreeBSD Foundation
3  * All rights reserved.
4  *
5  * This software was developed by Konstantin Belousov under sponsorship from
6  * the FreeBSD Foundation.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #include <sys/cdefs.h>
31 __FBSDID("$FreeBSD$");
32 
33 #include "opt_vm.h"
34 
35 #include <sys/param.h>
36 #include <sys/systm.h>
37 #include <sys/limits.h>
38 #include <sys/lock.h>
39 #include <sys/mutex.h>
40 
41 #include <vm/vm.h>
42 #include <vm/vm_page.h>
43 
44 #include <dev/drm2/drmP.h>
45 #include <dev/drm2/drm.h>
46 #include <dev/drm2/drm_sarea.h>
47 
48 /*
49  * We make up offsets for buffer objects so we can recognize them at
50  * mmap time.
51  */
52 
53 /* pgoff in mmap is an unsigned long, so we need to make sure that
54  * the faked up offset will fit
55  */
56 
57 #if ULONG_MAX == UINT64_MAX
58 #define DRM_FILE_PAGE_OFFSET_START ((0xFFFFFFFFUL >> PAGE_SHIFT) + 1)
59 #define DRM_FILE_PAGE_OFFSET_SIZE ((0xFFFFFFFFUL >> PAGE_SHIFT) * 16)
60 #else
61 #define DRM_FILE_PAGE_OFFSET_START ((0xFFFFFFFUL >> PAGE_SHIFT) + 1)
62 #define DRM_FILE_PAGE_OFFSET_SIZE ((0xFFFFFFFUL >> PAGE_SHIFT) * 16)
63 #endif
64 
65 int
66 drm_gem_init(struct drm_device *dev)
67 {
68 	struct drm_gem_mm *mm;
69 
70 	drm_gem_names_init(&dev->object_names);
71 	mm = malloc(sizeof(*mm), DRM_MEM_DRIVER, M_WAITOK);
72 	dev->mm_private = mm;
73 	if (drm_ht_create(&mm->offset_hash, 19) != 0) {
74 		free(mm, DRM_MEM_DRIVER);
75 		return (ENOMEM);
76 	}
77 	mm->idxunr = new_unrhdr(0, DRM_GEM_MAX_IDX, NULL);
78 	return (0);
79 }
80 
81 void
82 drm_gem_destroy(struct drm_device *dev)
83 {
84 	struct drm_gem_mm *mm;
85 
86 	mm = dev->mm_private;
87 	dev->mm_private = NULL;
88 	drm_ht_remove(&mm->offset_hash);
89 	delete_unrhdr(mm->idxunr);
90 	free(mm, DRM_MEM_DRIVER);
91 	drm_gem_names_fini(&dev->object_names);
92 }
93 
94 int
95 drm_gem_object_init(struct drm_device *dev, struct drm_gem_object *obj,
96     size_t size)
97 {
98 
99 	KASSERT((size & (PAGE_SIZE - 1)) == 0,
100 	    ("Bad size %ju", (uintmax_t)size));
101 
102 	obj->dev = dev;
103 	obj->vm_obj = vm_pager_allocate(OBJT_DEFAULT, NULL, size,
104 	    VM_PROT_READ | VM_PROT_WRITE, 0, curthread->td_ucred);
105 
106 	obj->refcount = 1;
107 	obj->handle_count = 0;
108 	obj->size = size;
109 
110 	return (0);
111 }
112 
113 int
114 drm_gem_private_object_init(struct drm_device *dev, struct drm_gem_object *obj,
115     size_t size)
116 {
117 
118 	MPASS((size & (PAGE_SIZE - 1)) == 0);
119 
120 	obj->dev = dev;
121 	obj->vm_obj = NULL;
122 
123 	obj->refcount = 1;
124 	atomic_set(&obj->handle_count, 0);
125 	obj->size = size;
126 
127 	return (0);
128 }
129 
130 
131 struct drm_gem_object *
132 drm_gem_object_alloc(struct drm_device *dev, size_t size)
133 {
134 	struct drm_gem_object *obj;
135 
136 	obj = malloc(sizeof(*obj), DRM_MEM_DRIVER, M_WAITOK | M_ZERO);
137 	if (drm_gem_object_init(dev, obj, size) != 0)
138 		goto free;
139 
140 	if (dev->driver->gem_init_object != NULL &&
141 	    dev->driver->gem_init_object(obj) != 0)
142 		goto dealloc;
143 	return (obj);
144 dealloc:
145 	vm_object_deallocate(obj->vm_obj);
146 free:
147 	free(obj, DRM_MEM_DRIVER);
148 	return (NULL);
149 }
150 
151 void
152 drm_gem_object_free(struct drm_gem_object *obj)
153 {
154 	struct drm_device *dev;
155 
156 	dev = obj->dev;
157 	DRM_LOCK_ASSERT(dev);
158 	if (dev->driver->gem_free_object != NULL)
159 		dev->driver->gem_free_object(obj);
160 }
161 
162 void
163 drm_gem_object_reference(struct drm_gem_object *obj)
164 {
165 
166 	KASSERT(obj->refcount > 0, ("Dandling obj %p", obj));
167 	refcount_acquire(&obj->refcount);
168 }
169 
170 void
171 drm_gem_object_unreference(struct drm_gem_object *obj)
172 {
173 
174 	if (obj == NULL)
175 		return;
176 	if (refcount_release(&obj->refcount))
177 		drm_gem_object_free(obj);
178 }
179 
180 void
181 drm_gem_object_unreference_unlocked(struct drm_gem_object *obj)
182 {
183 	struct drm_device *dev;
184 
185 	if (obj == NULL)
186 		return;
187 	dev = obj->dev;
188 	DRM_LOCK(dev);
189 	drm_gem_object_unreference(obj);
190 	DRM_UNLOCK(dev);
191 }
192 
193 void
194 drm_gem_object_handle_reference(struct drm_gem_object *obj)
195 {
196 
197 	drm_gem_object_reference(obj);
198 	atomic_add_rel_int(&obj->handle_count, 1);
199 }
200 
201 void
202 drm_gem_object_handle_free(struct drm_gem_object *obj)
203 {
204 	struct drm_device *dev;
205 	struct drm_gem_object *obj1;
206 
207 	dev = obj->dev;
208 	if (obj->name != 0) {
209 		obj1 = drm_gem_names_remove(&dev->object_names, obj->name);
210 		obj->name = 0;
211 		drm_gem_object_unreference(obj1);
212 	}
213 }
214 
215 void
216 drm_gem_object_handle_unreference(struct drm_gem_object *obj)
217 {
218 
219 	if (obj == NULL ||
220 	    atomic_load_acq_int(&obj->handle_count) == 0)
221 		return;
222 
223 	if (atomic_fetchadd_int(&obj->handle_count, -1) == 1)
224 		drm_gem_object_handle_free(obj);
225 	drm_gem_object_unreference(obj);
226 }
227 
228 void
229 drm_gem_object_handle_unreference_unlocked(struct drm_gem_object *obj)
230 {
231 
232 	if (obj == NULL ||
233 	    atomic_load_acq_int(&obj->handle_count) == 0)
234 		return;
235 
236 	if (atomic_fetchadd_int(&obj->handle_count, -1) == 1)
237 		drm_gem_object_handle_free(obj);
238 	drm_gem_object_unreference_unlocked(obj);
239 }
240 
241 int
242 drm_gem_handle_create(struct drm_file *file_priv, struct drm_gem_object *obj,
243     uint32_t *handle)
244 {
245 	int error;
246 
247 	error = drm_gem_name_create(&file_priv->object_names, obj, handle);
248 	if (error != 0)
249 		return (error);
250 	drm_gem_object_handle_reference(obj);
251 	return (0);
252 }
253 
254 int
255 drm_gem_handle_delete(struct drm_file *file_priv, uint32_t handle)
256 {
257 	struct drm_gem_object *obj;
258 
259 	obj = drm_gem_names_remove(&file_priv->object_names, handle);
260 	if (obj == NULL)
261 		return (EINVAL);
262 	drm_gem_object_handle_unreference_unlocked(obj);
263 	return (0);
264 }
265 
266 void
267 drm_gem_object_release(struct drm_gem_object *obj)
268 {
269 
270 	/*
271 	 * obj->vm_obj can be NULL for private gem objects.
272 	 */
273 	vm_object_deallocate(obj->vm_obj);
274 }
275 
276 int
277 drm_gem_open_ioctl(struct drm_device *dev, void *data,
278     struct drm_file *file_priv)
279 {
280 	struct drm_gem_open *args;
281 	struct drm_gem_object *obj;
282 	int ret;
283 	uint32_t handle;
284 
285 	if (!drm_core_check_feature(dev, DRIVER_GEM))
286 		return (ENODEV);
287 	args = data;
288 
289 	obj = drm_gem_name_ref(&dev->object_names, args->name,
290 	    (void (*)(void *))drm_gem_object_reference);
291 	if (obj == NULL)
292 		return (ENOENT);
293 	handle = 0;
294 	ret = drm_gem_handle_create(file_priv, obj, &handle);
295 	drm_gem_object_unreference_unlocked(obj);
296 	if (ret != 0)
297 		return (ret);
298 
299 	args->handle = handle;
300 	args->size = obj->size;
301 
302 	return (0);
303 }
304 
305 void
306 drm_gem_open(struct drm_device *dev, struct drm_file *file_priv)
307 {
308 
309 	drm_gem_names_init(&file_priv->object_names);
310 }
311 
312 static int
313 drm_gem_object_release_handle(uint32_t name, void *ptr, void *arg)
314 {
315 	struct drm_gem_object *obj;
316 
317 	obj = ptr;
318 	drm_gem_object_handle_unreference(obj);
319 	return (0);
320 }
321 
322 void
323 drm_gem_release(struct drm_device *dev, struct drm_file *file_priv)
324 {
325 
326 	drm_gem_names_foreach(&file_priv->object_names,
327 	    drm_gem_object_release_handle, NULL);
328 	drm_gem_names_fini(&file_priv->object_names);
329 }
330 
331 int
332 drm_gem_close_ioctl(struct drm_device *dev, void *data,
333     struct drm_file *file_priv)
334 {
335 	struct drm_gem_close *args;
336 
337 	if (!drm_core_check_feature(dev, DRIVER_GEM))
338 		return (ENODEV);
339 	args = data;
340 
341 	return (drm_gem_handle_delete(file_priv, args->handle));
342 }
343 
344 int
345 drm_gem_flink_ioctl(struct drm_device *dev, void *data,
346     struct drm_file *file_priv)
347 {
348 	struct drm_gem_flink *args;
349 	struct drm_gem_object *obj;
350 	int error;
351 
352 	if (!drm_core_check_feature(dev, DRIVER_GEM))
353 		return (ENODEV);
354 	args = data;
355 
356 	obj = drm_gem_name_ref(&file_priv->object_names, args->handle,
357 	    (void (*)(void *))drm_gem_object_reference);
358 	if (obj == NULL)
359 		return (ENOENT);
360 	error = drm_gem_name_create(&dev->object_names, obj, &obj->name);
361 	if (error != 0) {
362 		if (error == EALREADY)
363 			error = 0;
364 		drm_gem_object_unreference_unlocked(obj);
365 	}
366 	if (error == 0)
367 		args->name = obj->name;
368 	return (error);
369 }
370 
371 struct drm_gem_object *
372 drm_gem_object_lookup(struct drm_device *dev, struct drm_file *file_priv,
373     uint32_t handle)
374 {
375 	struct drm_gem_object *obj;
376 
377 	obj = drm_gem_name_ref(&file_priv->object_names, handle,
378 	    (void (*)(void *))drm_gem_object_reference);
379 	return (obj);
380 }
381 
382 static struct drm_gem_object *
383 drm_gem_object_from_offset(struct drm_device *dev, vm_ooffset_t offset)
384 {
385 	struct drm_gem_object *obj;
386 	struct drm_gem_mm *mm;
387 	struct drm_hash_item *map_list;
388 
389 	if ((offset & DRM_GEM_MAPPING_MASK) != DRM_GEM_MAPPING_KEY)
390 		return (NULL);
391 	offset &= ~DRM_GEM_MAPPING_KEY;
392 	mm = dev->mm_private;
393 	if (drm_ht_find_item(&mm->offset_hash, DRM_GEM_MAPPING_IDX(offset),
394 	    &map_list) != 0) {
395 	DRM_DEBUG("drm_gem_object_from_offset: offset 0x%jx obj not found\n",
396 		    (uintmax_t)offset);
397 		return (NULL);
398 	}
399 	obj = __containerof(map_list, struct drm_gem_object, map_list);
400 	return (obj);
401 }
402 
403 int
404 drm_gem_create_mmap_offset(struct drm_gem_object *obj)
405 {
406 	struct drm_device *dev;
407 	struct drm_gem_mm *mm;
408 	int ret;
409 
410 	if (obj->on_map)
411 		return (0);
412 	dev = obj->dev;
413 	mm = dev->mm_private;
414 	ret = 0;
415 
416 	obj->map_list.key = alloc_unr(mm->idxunr);
417 	ret = drm_ht_insert_item(&mm->offset_hash, &obj->map_list);
418 	if (ret != 0) {
419 		DRM_ERROR("failed to add to map hash\n");
420 		free_unr(mm->idxunr, obj->map_list.key);
421 		return (ret);
422 	}
423 	obj->on_map = true;
424 	return (0);
425 }
426 
427 void
428 drm_gem_free_mmap_offset(struct drm_gem_object *obj)
429 {
430 	struct drm_hash_item *list;
431 	struct drm_gem_mm *mm;
432 
433 	if (!obj->on_map)
434 		return;
435 	mm = obj->dev->mm_private;
436 	list = &obj->map_list;
437 
438 	drm_ht_remove_item(&mm->offset_hash, list);
439 	free_unr(mm->idxunr, list->key);
440 	obj->on_map = false;
441 }
442 
443 int
444 drm_gem_mmap_single(struct drm_device *dev, vm_ooffset_t *offset, vm_size_t size,
445     struct vm_object **obj_res, int nprot)
446 {
447 	struct drm_gem_object *gem_obj;
448 	struct vm_object *vm_obj;
449 
450 	DRM_LOCK(dev);
451 	gem_obj = drm_gem_object_from_offset(dev, *offset);
452 	if (gem_obj == NULL) {
453 		DRM_UNLOCK(dev);
454 		return (ENODEV);
455 	}
456 	drm_gem_object_reference(gem_obj);
457 	DRM_UNLOCK(dev);
458 	vm_obj = cdev_pager_allocate(gem_obj, OBJT_MGTDEVICE,
459 	    dev->driver->gem_pager_ops, size, nprot,
460 	    DRM_GEM_MAPPING_MAPOFF(*offset), curthread->td_ucred);
461 	if (vm_obj == NULL) {
462 		drm_gem_object_unreference_unlocked(gem_obj);
463 		return (EINVAL);
464 	}
465 	*offset = DRM_GEM_MAPPING_MAPOFF(*offset);
466 	*obj_res = vm_obj;
467 	return (0);
468 }
469 
470 void
471 drm_gem_pager_dtr(void *handle)
472 {
473 	struct drm_gem_object *obj;
474 	struct drm_device *dev;
475 
476 	obj = handle;
477 	dev = obj->dev;
478 
479 	DRM_LOCK(dev);
480 	drm_gem_free_mmap_offset(obj);
481 	drm_gem_object_unreference(obj);
482 	DRM_UNLOCK(dev);
483 }
484