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/dma-resv.h>
 39
 40#include <drm/drm_vma_manager.h>
 41
 42struct iosys_map;
 43struct drm_gem_object;
 44
 45/**
 46 * struct drm_gem_object_funcs - GEM object functions
 47 */
 48struct drm_gem_object_funcs {
 49	/**
 50	 * @free:
 51	 *
 52	 * Deconstructor for drm_gem_objects.
 53	 *
 54	 * This callback is mandatory.
 55	 */
 56	void (*free)(struct drm_gem_object *obj);
 57
 58	/**
 59	 * @open:
 60	 *
 61	 * Called upon GEM handle creation.
 62	 *
 63	 * This callback is optional.
 64	 */
 65	int (*open)(struct drm_gem_object *obj, struct drm_file *file);
 66
 67	/**
 68	 * @close:
 69	 *
 70	 * Called upon GEM handle release.
 71	 *
 72	 * This callback is optional.
 73	 */
 74	void (*close)(struct drm_gem_object *obj, struct drm_file *file);
 75
 76	/**
 77	 * @print_info:
 78	 *
 79	 * If driver subclasses struct &drm_gem_object, it can implement this
 80	 * optional hook for printing additional driver specific info.
 81	 *
 82	 * drm_printf_indent() should be used in the callback passing it the
 83	 * indent argument.
 84	 *
 85	 * This callback is called from drm_gem_print_info().
 86	 *
 87	 * This callback is optional.
 88	 */
 89	void (*print_info)(struct drm_printer *p, unsigned int indent,
 90			   const struct drm_gem_object *obj);
 91
 92	/**
 93	 * @export:
 94	 *
 95	 * Export backing buffer as a &dma_buf.
 96	 * If this is not set drm_gem_prime_export() is used.
 97	 *
 98	 * This callback is optional.
 99	 */
100	struct dma_buf *(*export)(struct drm_gem_object *obj, int flags);
101
102	/**
103	 * @pin:
104	 *
105	 * Pin backing buffer in memory. Used by the drm_gem_map_attach() helper.
106	 *
107	 * This callback is optional.
108	 */
109	int (*pin)(struct drm_gem_object *obj);
110
111	/**
112	 * @unpin:
113	 *
114	 * Unpin backing buffer. Used by the drm_gem_map_detach() helper.
115	 *
116	 * This callback is optional.
117	 */
118	void (*unpin)(struct drm_gem_object *obj);
119
120	/**
121	 * @get_sg_table:
122	 *
123	 * Returns a Scatter-Gather table representation of the buffer.
124	 * Used when exporting a buffer by the drm_gem_map_dma_buf() helper.
125	 * Releasing is done by calling dma_unmap_sg_attrs() and sg_free_table()
126	 * in drm_gem_unmap_buf(), therefore these helpers and this callback
127	 * here cannot be used for sg tables pointing at driver private memory
128	 * ranges.
129	 *
130	 * See also drm_prime_pages_to_sg().
131	 */
132	struct sg_table *(*get_sg_table)(struct drm_gem_object *obj);
133
134	/**
135	 * @vmap:
136	 *
137	 * Returns a virtual address for the buffer. Used by the
138	 * drm_gem_dmabuf_vmap() helper.
139	 *
140	 * This callback is optional.
141	 */
142	int (*vmap)(struct drm_gem_object *obj, struct iosys_map *map);
143
144	/**
145	 * @vunmap:
146	 *
147	 * Releases the address previously returned by @vmap. Used by the
148	 * drm_gem_dmabuf_vunmap() helper.
149	 *
150	 * This callback is optional.
151	 */
152	void (*vunmap)(struct drm_gem_object *obj, struct iosys_map *map);
153
154	/**
155	 * @mmap:
156	 *
157	 * Handle mmap() of the gem object, setup vma accordingly.
158	 *
159	 * This callback is optional.
160	 *
161	 * The callback is used by both drm_gem_mmap_obj() and
162	 * drm_gem_prime_mmap().  When @mmap is present @vm_ops is not
163	 * used, the @mmap callback must set vma->vm_ops instead.
164	 */
165	int (*mmap)(struct drm_gem_object *obj, struct vm_area_struct *vma);
166
167	/**
168	 * @vm_ops:
169	 *
170	 * Virtual memory operations used with mmap.
171	 *
172	 * This is optional but necessary for mmap support.
173	 */
174	const struct vm_operations_struct *vm_ops;
175};
176
177/**
178 * struct drm_gem_lru - A simple LRU helper
179 *
180 * A helper for tracking GEM objects in a given state, to aid in
181 * driver's shrinker implementation.  Tracks the count of pages
182 * for lockless &shrinker.count_objects, and provides
183 * &drm_gem_lru_scan for driver's &shrinker.scan_objects
184 * implementation.
185 */
186struct drm_gem_lru {
187	/**
188	 * @lock:
189	 *
190	 * Lock protecting movement of GEM objects between LRUs.  All
191	 * LRUs that the object can move between should be protected
192	 * by the same lock.
193	 */
194	struct mutex *lock;
195
196	/**
197	 * @count:
198	 *
199	 * The total number of backing pages of the GEM objects in
200	 * this LRU.
201	 */
202	long count;
203
204	/**
205	 * @list:
206	 *
207	 * The LRU list.
208	 */
209	struct list_head list;
210};
211
212/**
213 * struct drm_gem_object - GEM buffer object
214 *
215 * This structure defines the generic parts for GEM buffer objects, which are
216 * mostly around handling mmap and userspace handles.
217 *
218 * Buffer objects are often abbreviated to BO.
219 */
220struct drm_gem_object {
221	/**
222	 * @refcount:
223	 *
224	 * Reference count of this object
225	 *
226	 * Please use drm_gem_object_get() to acquire and drm_gem_object_put_locked()
227	 * or drm_gem_object_put() to release a reference to a GEM
228	 * buffer object.
229	 */
230	struct kref refcount;
231
232	/**
233	 * @handle_count:
234	 *
235	 * This is the GEM file_priv handle count of this object.
236	 *
237	 * Each handle also holds a reference. Note that when the handle_count
238	 * drops to 0 any global names (e.g. the id in the flink namespace) will
239	 * be cleared.
240	 *
241	 * Protected by &drm_device.object_name_lock.
242	 */
243	unsigned handle_count;
244
245	/**
246	 * @dev: DRM dev this object belongs to.
247	 */
248	struct drm_device *dev;
249
250	/**
251	 * @filp:
252	 *
253	 * SHMEM file node used as backing storage for swappable buffer objects.
254	 * GEM also supports driver private objects with driver-specific backing
255	 * storage (contiguous DMA memory, special reserved blocks). In this
256	 * case @filp is NULL.
257	 */
258	struct file *filp;
259
260	/**
261	 * @vma_node:
262	 *
263	 * Mapping info for this object to support mmap. Drivers are supposed to
264	 * allocate the mmap offset using drm_gem_create_mmap_offset(). The
265	 * offset itself can be retrieved using drm_vma_node_offset_addr().
266	 *
267	 * Memory mapping itself is handled by drm_gem_mmap(), which also checks
268	 * that userspace is allowed to access the object.
269	 */
270	struct drm_vma_offset_node vma_node;
271
272	/**
273	 * @size:
274	 *
275	 * Size of the object, in bytes.  Immutable over the object's
276	 * lifetime.
277	 */
278	size_t size;
279
280	/**
281	 * @name:
282	 *
283	 * Global name for this object, starts at 1. 0 means unnamed.
284	 * Access is covered by &drm_device.object_name_lock. This is used by
285	 * the GEM_FLINK and GEM_OPEN ioctls.
286	 */
287	int name;
288
289	/**
290	 * @dma_buf:
291	 *
292	 * dma-buf associated with this GEM object.
293	 *
294	 * Pointer to the dma-buf associated with this gem object (either
295	 * through importing or exporting). We break the resulting reference
296	 * loop when the last gem handle for this object is released.
297	 *
298	 * Protected by &drm_device.object_name_lock.
299	 */
300	struct dma_buf *dma_buf;
301
302	/**
303	 * @import_attach:
304	 *
305	 * dma-buf attachment backing this object.
306	 *
307	 * Any foreign dma_buf imported as a gem object has this set to the
308	 * attachment point for the device. This is invariant over the lifetime
309	 * of a gem object.
310	 *
311	 * The &drm_gem_object_funcs.free callback is responsible for
312	 * cleaning up the dma_buf attachment and references acquired at import
313	 * time.
314	 *
315	 * Note that the drm gem/prime core does not depend upon drivers setting
316	 * this field any more. So for drivers where this doesn't make sense
317	 * (e.g. virtual devices or a displaylink behind an usb bus) they can
318	 * simply leave it as NULL.
319	 */
320	struct dma_buf_attachment *import_attach;
321
322	/**
323	 * @resv:
324	 *
325	 * Pointer to reservation object associated with the this GEM object.
326	 *
327	 * Normally (@resv == &@_resv) except for imported GEM objects.
328	 */
329	struct dma_resv *resv;
330
331	/**
332	 * @_resv:
333	 *
334	 * A reservation object for this GEM object.
335	 *
336	 * This is unused for imported GEM objects.
337	 */
338	struct dma_resv _resv;
339
340	/**
341	 * @funcs:
342	 *
343	 * Optional GEM object functions. If this is set, it will be used instead of the
344	 * corresponding &drm_driver GEM callbacks.
345	 *
346	 * New drivers should use this.
347	 *
348	 */
349	const struct drm_gem_object_funcs *funcs;
350
351	/**
352	 * @lru_node:
353	 *
354	 * List node in a &drm_gem_lru.
355	 */
356	struct list_head lru_node;
357
358	/**
359	 * @lru:
360	 *
361	 * The current LRU list that the GEM object is on.
362	 */
363	struct drm_gem_lru *lru;
364};
365
366/**
367 * DRM_GEM_FOPS - Default drm GEM file operations
368 *
369 * This macro provides a shorthand for setting the GEM file ops in the
370 * &file_operations structure.  If all you need are the default ops, use
371 * DEFINE_DRM_GEM_FOPS instead.
372 */
373#define DRM_GEM_FOPS \
374	.open		= drm_open,\
375	.release	= drm_release,\
376	.unlocked_ioctl	= drm_ioctl,\
377	.compat_ioctl	= drm_compat_ioctl,\
378	.poll		= drm_poll,\
379	.read		= drm_read,\
380	.llseek		= noop_llseek,\
381	.mmap		= drm_gem_mmap
382
383/**
384 * DEFINE_DRM_GEM_FOPS() - macro to generate file operations for GEM drivers
385 * @name: name for the generated structure
386 *
387 * This macro autogenerates a suitable &struct file_operations for GEM based
388 * drivers, which can be assigned to &drm_driver.fops. Note that this structure
389 * cannot be shared between drivers, because it contains a reference to the
390 * current module using THIS_MODULE.
391 *
392 * Note that the declaration is already marked as static - if you need a
393 * non-static version of this you're probably doing it wrong and will break the
394 * THIS_MODULE reference by accident.
395 */
396#define DEFINE_DRM_GEM_FOPS(name) \
397	static const struct file_operations name = {\
398		.owner		= THIS_MODULE,\
399		DRM_GEM_FOPS,\
400	}
401
402void drm_gem_object_release(struct drm_gem_object *obj);
403void drm_gem_object_free(struct kref *kref);
404int drm_gem_object_init(struct drm_device *dev,
405			struct drm_gem_object *obj, size_t size);
406void drm_gem_private_object_init(struct drm_device *dev,
407				 struct drm_gem_object *obj, size_t size);
408void drm_gem_vm_open(struct vm_area_struct *vma);
409void drm_gem_vm_close(struct vm_area_struct *vma);
410int drm_gem_mmap_obj(struct drm_gem_object *obj, unsigned long obj_size,
411		     struct vm_area_struct *vma);
412int drm_gem_mmap(struct file *filp, struct vm_area_struct *vma);
413
414/**
415 * drm_gem_object_get - acquire a GEM buffer object reference
416 * @obj: GEM buffer object
417 *
418 * This function acquires an additional reference to @obj. It is illegal to
419 * call this without already holding a reference. No locks required.
420 */
421static inline void drm_gem_object_get(struct drm_gem_object *obj)
422{
423	kref_get(&obj->refcount);
424}
425
426__attribute__((nonnull))
427static inline void
428__drm_gem_object_put(struct drm_gem_object *obj)
429{
430	kref_put(&obj->refcount, drm_gem_object_free);
431}
432
433/**
434 * drm_gem_object_put - drop a GEM buffer object reference
435 * @obj: GEM buffer object
436 *
437 * This releases a reference to @obj.
438 */
439static inline void
440drm_gem_object_put(struct drm_gem_object *obj)
441{
442	if (obj)
443		__drm_gem_object_put(obj);
444}
445
446int drm_gem_handle_create(struct drm_file *file_priv,
447			  struct drm_gem_object *obj,
448			  u32 *handlep);
449int drm_gem_handle_delete(struct drm_file *filp, u32 handle);
450
451
452void drm_gem_free_mmap_offset(struct drm_gem_object *obj);
453int drm_gem_create_mmap_offset(struct drm_gem_object *obj);
454int drm_gem_create_mmap_offset_size(struct drm_gem_object *obj, size_t size);
455
456struct page **drm_gem_get_pages(struct drm_gem_object *obj);
457void drm_gem_put_pages(struct drm_gem_object *obj, struct page **pages,
458		bool dirty, bool accessed);
459
460int drm_gem_vmap_unlocked(struct drm_gem_object *obj, struct iosys_map *map);
461void drm_gem_vunmap_unlocked(struct drm_gem_object *obj, struct iosys_map *map);
462
463int drm_gem_objects_lookup(struct drm_file *filp, void __user *bo_handles,
464			   int count, struct drm_gem_object ***objs_out);
465struct drm_gem_object *drm_gem_object_lookup(struct drm_file *filp, u32 handle);
466long drm_gem_dma_resv_wait(struct drm_file *filep, u32 handle,
467				    bool wait_all, unsigned long timeout);
468int drm_gem_lock_reservations(struct drm_gem_object **objs, int count,
469			      struct ww_acquire_ctx *acquire_ctx);
470void drm_gem_unlock_reservations(struct drm_gem_object **objs, int count,
471				 struct ww_acquire_ctx *acquire_ctx);
472int drm_gem_dumb_map_offset(struct drm_file *file, struct drm_device *dev,
473			    u32 handle, u64 *offset);
474
475void drm_gem_lru_init(struct drm_gem_lru *lru, struct mutex *lock);
476void drm_gem_lru_remove(struct drm_gem_object *obj);
477void drm_gem_lru_move_tail(struct drm_gem_lru *lru, struct drm_gem_object *obj);
478unsigned long drm_gem_lru_scan(struct drm_gem_lru *lru, unsigned nr_to_scan,
479			       bool (*shrink)(struct drm_gem_object *obj));
480
481#endif /* __DRM_GEM_H__ */