xref: /openbmc/linux/include/drm/drm_gem.h (revision bb3982b4)
1 #ifndef __DRM_GEM_H__
2 #define __DRM_GEM_H__
3 
4 /*
5  * GEM Graphics Execution Manager Driver Interfaces
6  *
7  * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas.
8  * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
9  * Copyright (c) 2009-2010, Code Aurora Forum.
10  * All rights reserved.
11  * Copyright © 2014 Intel Corporation
12  *   Daniel Vetter <daniel.vetter@ffwll.ch>
13  *
14  * Author: Rickard E. (Rik) Faith <faith@valinux.com>
15  * Author: Gareth Hughes <gareth@valinux.com>
16  *
17  * Permission is hereby granted, free of charge, to any person obtaining a
18  * copy of this software and associated documentation files (the "Software"),
19  * to deal in the Software without restriction, including without limitation
20  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
21  * and/or sell copies of the Software, and to permit persons to whom the
22  * Software is furnished to do so, subject to the following conditions:
23  *
24  * The above copyright notice and this permission notice (including the next
25  * paragraph) shall be included in all copies or substantial portions of the
26  * Software.
27  *
28  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
29  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
30  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
31  * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
32  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
33  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
34  * OTHER DEALINGS IN THE SOFTWARE.
35  */
36 
37 #include <linux/kref.h>
38 #include <linux/reservation.h>
39 
40 #include <drm/drm_vma_manager.h>
41 
42 struct drm_gem_object;
43 
44 /**
45  * struct drm_gem_object_funcs - GEM object functions
46  */
47 struct drm_gem_object_funcs {
48 	/**
49 	 * @free:
50 	 *
51 	 * Deconstructor for drm_gem_objects.
52 	 *
53 	 * This callback is mandatory.
54 	 */
55 	void (*free)(struct drm_gem_object *obj);
56 
57 	/**
58 	 * @open:
59 	 *
60 	 * Called upon GEM handle creation.
61 	 *
62 	 * This callback is optional.
63 	 */
64 	int (*open)(struct drm_gem_object *obj, struct drm_file *file);
65 
66 	/**
67 	 * @close:
68 	 *
69 	 * Called upon GEM handle release.
70 	 *
71 	 * This callback is optional.
72 	 */
73 	void (*close)(struct drm_gem_object *obj, struct drm_file *file);
74 
75 	/**
76 	 * @print_info:
77 	 *
78 	 * If driver subclasses struct &drm_gem_object, it can implement this
79 	 * optional hook for printing additional driver specific info.
80 	 *
81 	 * drm_printf_indent() should be used in the callback passing it the
82 	 * indent argument.
83 	 *
84 	 * This callback is called from drm_gem_print_info().
85 	 *
86 	 * This callback is optional.
87 	 */
88 	void (*print_info)(struct drm_printer *p, unsigned int indent,
89 			   const struct drm_gem_object *obj);
90 
91 	/**
92 	 * @export:
93 	 *
94 	 * Export backing buffer as a &dma_buf.
95 	 * If this is not set drm_gem_prime_export() is used.
96 	 *
97 	 * This callback is optional.
98 	 */
99 	struct dma_buf *(*export)(struct drm_gem_object *obj, int flags);
100 
101 	/**
102 	 * @pin:
103 	 *
104 	 * Pin backing buffer in memory.
105 	 *
106 	 * This callback is optional.
107 	 */
108 	int (*pin)(struct drm_gem_object *obj);
109 
110 	/**
111 	 * @unpin:
112 	 *
113 	 * Unpin backing buffer.
114 	 *
115 	 * This callback is optional.
116 	 */
117 	void (*unpin)(struct drm_gem_object *obj);
118 
119 	/**
120 	 * @get_sg_table:
121 	 *
122 	 * Returns a Scatter-Gather table representation of the buffer.
123 	 * Used when exporting a buffer.
124 	 *
125 	 * This callback is mandatory if buffer export is supported.
126 	 */
127 	struct sg_table *(*get_sg_table)(struct drm_gem_object *obj);
128 
129 	/**
130 	 * @vmap:
131 	 *
132 	 * Returns a virtual address for the buffer.
133 	 *
134 	 * This callback is optional.
135 	 */
136 	void *(*vmap)(struct drm_gem_object *obj);
137 
138 	/**
139 	 * @vunmap:
140 	 *
141 	 * Releases the the address previously returned by @vmap.
142 	 *
143 	 * This callback is optional.
144 	 */
145 	void (*vunmap)(struct drm_gem_object *obj, void *vaddr);
146 
147 	/**
148 	 * @vm_ops:
149 	 *
150 	 * Virtual memory operations used with mmap.
151 	 *
152 	 * This is optional but necessary for mmap support.
153 	 */
154 	const struct vm_operations_struct *vm_ops;
155 };
156 
157 /**
158  * struct drm_gem_object - GEM buffer object
159  *
160  * This structure defines the generic parts for GEM buffer objects, which are
161  * mostly around handling mmap and userspace handles.
162  *
163  * Buffer objects are often abbreviated to BO.
164  */
165 struct drm_gem_object {
166 	/**
167 	 * @refcount:
168 	 *
169 	 * Reference count of this object
170 	 *
171 	 * Please use drm_gem_object_get() to acquire and drm_gem_object_put()
172 	 * or drm_gem_object_put_unlocked() to release a reference to a GEM
173 	 * buffer object.
174 	 */
175 	struct kref refcount;
176 
177 	/**
178 	 * @handle_count:
179 	 *
180 	 * This is the GEM file_priv handle count of this object.
181 	 *
182 	 * Each handle also holds a reference. Note that when the handle_count
183 	 * drops to 0 any global names (e.g. the id in the flink namespace) will
184 	 * be cleared.
185 	 *
186 	 * Protected by &drm_device.object_name_lock.
187 	 */
188 	unsigned handle_count;
189 
190 	/**
191 	 * @dev: DRM dev this object belongs to.
192 	 */
193 	struct drm_device *dev;
194 
195 	/**
196 	 * @filp:
197 	 *
198 	 * SHMEM file node used as backing storage for swappable buffer objects.
199 	 * GEM also supports driver private objects with driver-specific backing
200 	 * storage (contiguous CMA memory, special reserved blocks). In this
201 	 * case @filp is NULL.
202 	 */
203 	struct file *filp;
204 
205 	/**
206 	 * @vma_node:
207 	 *
208 	 * Mapping info for this object to support mmap. Drivers are supposed to
209 	 * allocate the mmap offset using drm_gem_create_mmap_offset(). The
210 	 * offset itself can be retrieved using drm_vma_node_offset_addr().
211 	 *
212 	 * Memory mapping itself is handled by drm_gem_mmap(), which also checks
213 	 * that userspace is allowed to access the object.
214 	 */
215 	struct drm_vma_offset_node vma_node;
216 
217 	/**
218 	 * @size:
219 	 *
220 	 * Size of the object, in bytes.  Immutable over the object's
221 	 * lifetime.
222 	 */
223 	size_t size;
224 
225 	/**
226 	 * @name:
227 	 *
228 	 * Global name for this object, starts at 1. 0 means unnamed.
229 	 * Access is covered by &drm_device.object_name_lock. This is used by
230 	 * the GEM_FLINK and GEM_OPEN ioctls.
231 	 */
232 	int name;
233 
234 	/**
235 	 * @dma_buf:
236 	 *
237 	 * dma-buf associated with this GEM object.
238 	 *
239 	 * Pointer to the dma-buf associated with this gem object (either
240 	 * through importing or exporting). We break the resulting reference
241 	 * loop when the last gem handle for this object is released.
242 	 *
243 	 * Protected by &drm_device.object_name_lock.
244 	 */
245 	struct dma_buf *dma_buf;
246 
247 	/**
248 	 * @import_attach:
249 	 *
250 	 * dma-buf attachment backing this object.
251 	 *
252 	 * Any foreign dma_buf imported as a gem object has this set to the
253 	 * attachment point for the device. This is invariant over the lifetime
254 	 * of a gem object.
255 	 *
256 	 * The &drm_driver.gem_free_object callback is responsible for cleaning
257 	 * up the dma_buf attachment and references acquired at import time.
258 	 *
259 	 * Note that the drm gem/prime core does not depend upon drivers setting
260 	 * this field any more. So for drivers where this doesn't make sense
261 	 * (e.g. virtual devices or a displaylink behind an usb bus) they can
262 	 * simply leave it as NULL.
263 	 */
264 	struct dma_buf_attachment *import_attach;
265 
266 	/**
267 	 * @resv:
268 	 *
269 	 * Pointer to reservation object associated with the this GEM object.
270 	 *
271 	 * Normally (@resv == &@_resv) except for imported GEM objects.
272 	 */
273 	struct reservation_object *resv;
274 
275 	/**
276 	 * @_resv:
277 	 *
278 	 * A reservation object for this GEM object.
279 	 *
280 	 * This is unused for imported GEM objects.
281 	 */
282 	struct reservation_object _resv;
283 
284 	/**
285 	 * @funcs:
286 	 *
287 	 * Optional GEM object functions. If this is set, it will be used instead of the
288 	 * corresponding &drm_driver GEM callbacks.
289 	 *
290 	 * New drivers should use this.
291 	 *
292 	 */
293 	const struct drm_gem_object_funcs *funcs;
294 };
295 
296 /**
297  * DEFINE_DRM_GEM_FOPS() - macro to generate file operations for GEM drivers
298  * @name: name for the generated structure
299  *
300  * This macro autogenerates a suitable &struct file_operations for GEM based
301  * drivers, which can be assigned to &drm_driver.fops. Note that this structure
302  * cannot be shared between drivers, because it contains a reference to the
303  * current module using THIS_MODULE.
304  *
305  * Note that the declaration is already marked as static - if you need a
306  * non-static version of this you're probably doing it wrong and will break the
307  * THIS_MODULE reference by accident.
308  */
309 #define DEFINE_DRM_GEM_FOPS(name) \
310 	static const struct file_operations name = {\
311 		.owner		= THIS_MODULE,\
312 		.open		= drm_open,\
313 		.release	= drm_release,\
314 		.unlocked_ioctl	= drm_ioctl,\
315 		.compat_ioctl	= drm_compat_ioctl,\
316 		.poll		= drm_poll,\
317 		.read		= drm_read,\
318 		.llseek		= noop_llseek,\
319 		.mmap		= drm_gem_mmap,\
320 	}
321 
322 void drm_gem_object_release(struct drm_gem_object *obj);
323 void drm_gem_object_free(struct kref *kref);
324 int drm_gem_object_init(struct drm_device *dev,
325 			struct drm_gem_object *obj, size_t size);
326 void drm_gem_private_object_init(struct drm_device *dev,
327 				 struct drm_gem_object *obj, size_t size);
328 void drm_gem_vm_open(struct vm_area_struct *vma);
329 void drm_gem_vm_close(struct vm_area_struct *vma);
330 int drm_gem_mmap_obj(struct drm_gem_object *obj, unsigned long obj_size,
331 		     struct vm_area_struct *vma);
332 int drm_gem_mmap(struct file *filp, struct vm_area_struct *vma);
333 
334 /**
335  * drm_gem_object_get - acquire a GEM buffer object reference
336  * @obj: GEM buffer object
337  *
338  * This function acquires an additional reference to @obj. It is illegal to
339  * call this without already holding a reference. No locks required.
340  */
341 static inline void drm_gem_object_get(struct drm_gem_object *obj)
342 {
343 	kref_get(&obj->refcount);
344 }
345 
346 /**
347  * __drm_gem_object_put - raw function to release a GEM buffer object reference
348  * @obj: GEM buffer object
349  *
350  * This function is meant to be used by drivers which are not encumbered with
351  * &drm_device.struct_mutex legacy locking and which are using the
352  * gem_free_object_unlocked callback. It avoids all the locking checks and
353  * locking overhead of drm_gem_object_put() and drm_gem_object_put_unlocked().
354  *
355  * Drivers should never call this directly in their code. Instead they should
356  * wrap it up into a ``driver_gem_object_put(struct driver_gem_object *obj)``
357  * wrapper function, and use that. Shared code should never call this, to
358  * avoid breaking drivers by accident which still depend upon
359  * &drm_device.struct_mutex locking.
360  */
361 static inline void
362 __drm_gem_object_put(struct drm_gem_object *obj)
363 {
364 	kref_put(&obj->refcount, drm_gem_object_free);
365 }
366 
367 void drm_gem_object_put_unlocked(struct drm_gem_object *obj);
368 void drm_gem_object_put(struct drm_gem_object *obj);
369 
370 int drm_gem_handle_create(struct drm_file *file_priv,
371 			  struct drm_gem_object *obj,
372 			  u32 *handlep);
373 int drm_gem_handle_delete(struct drm_file *filp, u32 handle);
374 
375 
376 void drm_gem_free_mmap_offset(struct drm_gem_object *obj);
377 int drm_gem_create_mmap_offset(struct drm_gem_object *obj);
378 int drm_gem_create_mmap_offset_size(struct drm_gem_object *obj, size_t size);
379 
380 struct page **drm_gem_get_pages(struct drm_gem_object *obj);
381 void drm_gem_put_pages(struct drm_gem_object *obj, struct page **pages,
382 		bool dirty, bool accessed);
383 
384 int drm_gem_objects_lookup(struct drm_file *filp, void __user *bo_handles,
385 			   int count, struct drm_gem_object ***objs_out);
386 struct drm_gem_object *drm_gem_object_lookup(struct drm_file *filp, u32 handle);
387 long drm_gem_reservation_object_wait(struct drm_file *filep, u32 handle,
388 				    bool wait_all, unsigned long timeout);
389 int drm_gem_lock_reservations(struct drm_gem_object **objs, int count,
390 			      struct ww_acquire_ctx *acquire_ctx);
391 void drm_gem_unlock_reservations(struct drm_gem_object **objs, int count,
392 				 struct ww_acquire_ctx *acquire_ctx);
393 int drm_gem_fence_array_add(struct xarray *fence_array,
394 			    struct dma_fence *fence);
395 int drm_gem_fence_array_add_implicit(struct xarray *fence_array,
396 				     struct drm_gem_object *obj,
397 				     bool write);
398 int drm_gem_dumb_map_offset(struct drm_file *file, struct drm_device *dev,
399 			    u32 handle, u64 *offset);
400 int drm_gem_dumb_destroy(struct drm_file *file,
401 			 struct drm_device *dev,
402 			 uint32_t handle);
403 
404 int drm_gem_pin(struct drm_gem_object *obj);
405 void drm_gem_unpin(struct drm_gem_object *obj);
406 void *drm_gem_vmap(struct drm_gem_object *obj);
407 void drm_gem_vunmap(struct drm_gem_object *obj, void *vaddr);
408 
409 #endif /* __DRM_GEM_H__ */
410