xref: /linux/include/drm/drm_gem_shmem_helper.h (revision ca220141fa8ebae09765a242076b2b77338106b0)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 
3 #ifndef __DRM_GEM_SHMEM_HELPER_H__
4 #define __DRM_GEM_SHMEM_HELPER_H__
5 
6 #include <linux/fs.h>
7 #include <linux/mm.h>
8 #include <linux/mutex.h>
9 
10 #include <drm/drm_file.h>
11 #include <drm/drm_gem.h>
12 #include <drm/drm_ioctl.h>
13 #include <drm/drm_prime.h>
14 
15 struct dma_buf_attachment;
16 struct drm_mode_create_dumb;
17 struct drm_printer;
18 struct sg_table;
19 
20 /**
21  * struct drm_gem_shmem_object - GEM object backed by shmem
22  */
23 struct drm_gem_shmem_object {
24 	/**
25 	 * @base: Base GEM object
26 	 */
27 	struct drm_gem_object base;
28 
29 	/**
30 	 * @pages: Page table
31 	 */
32 	struct page **pages;
33 
34 	/**
35 	 * @pages_use_count:
36 	 *
37 	 * Reference count on the pages table.
38 	 * The pages are put when the count reaches zero.
39 	 */
40 	refcount_t pages_use_count;
41 
42 	/**
43 	 * @pages_pin_count:
44 	 *
45 	 * Reference count on the pinned pages table.
46 	 *
47 	 * Pages are hard-pinned and reside in memory if count
48 	 * greater than zero. Otherwise, when count is zero, the pages are
49 	 * allowed to be evicted and purged by memory shrinker.
50 	 */
51 	refcount_t pages_pin_count;
52 
53 	/**
54 	 * @madv: State for madvise
55 	 *
56 	 * 0 is active/inuse.
57 	 * A negative value is the object is purged.
58 	 * Positive values are driver specific and not used by the helpers.
59 	 */
60 	int madv;
61 
62 	/**
63 	 * @madv_list: List entry for madvise tracking
64 	 *
65 	 * Typically used by drivers to track purgeable objects
66 	 */
67 	struct list_head madv_list;
68 
69 	/**
70 	 * @sgt: Scatter/gather table for imported PRIME buffers
71 	 */
72 	struct sg_table *sgt;
73 
74 	/**
75 	 * @vaddr: Kernel virtual address of the backing memory
76 	 */
77 	void *vaddr;
78 
79 	/**
80 	 * @vmap_use_count:
81 	 *
82 	 * Reference count on the virtual address.
83 	 * The address are un-mapped when the count reaches zero.
84 	 */
85 	refcount_t vmap_use_count;
86 
87 	/**
88 	 * @pages_mark_dirty_on_put:
89 	 *
90 	 * Mark pages as dirty when they are put.
91 	 */
92 	bool pages_mark_dirty_on_put : 1;
93 
94 	/**
95 	 * @pages_mark_accessed_on_put:
96 	 *
97 	 * Mark pages as accessed when they are put.
98 	 */
99 	bool pages_mark_accessed_on_put : 1;
100 
101 	/**
102 	 * @map_wc: map object write-combined (instead of using shmem defaults).
103 	 */
104 	bool map_wc : 1;
105 };
106 
107 #define to_drm_gem_shmem_obj(obj) \
108 	container_of(obj, struct drm_gem_shmem_object, base)
109 
110 int drm_gem_shmem_init(struct drm_device *dev, struct drm_gem_shmem_object *shmem, size_t size);
111 struct drm_gem_shmem_object *drm_gem_shmem_create(struct drm_device *dev, size_t size);
112 void drm_gem_shmem_release(struct drm_gem_shmem_object *shmem);
113 void drm_gem_shmem_free(struct drm_gem_shmem_object *shmem);
114 
115 void drm_gem_shmem_put_pages_locked(struct drm_gem_shmem_object *shmem);
116 int drm_gem_shmem_pin(struct drm_gem_shmem_object *shmem);
117 void drm_gem_shmem_unpin(struct drm_gem_shmem_object *shmem);
118 int drm_gem_shmem_vmap_locked(struct drm_gem_shmem_object *shmem,
119 			      struct iosys_map *map);
120 void drm_gem_shmem_vunmap_locked(struct drm_gem_shmem_object *shmem,
121 				 struct iosys_map *map);
122 int drm_gem_shmem_mmap(struct drm_gem_shmem_object *shmem, struct vm_area_struct *vma);
123 
124 int drm_gem_shmem_pin_locked(struct drm_gem_shmem_object *shmem);
125 void drm_gem_shmem_unpin_locked(struct drm_gem_shmem_object *shmem);
126 
127 int drm_gem_shmem_madvise_locked(struct drm_gem_shmem_object *shmem, int madv);
128 
129 static inline bool drm_gem_shmem_is_purgeable(struct drm_gem_shmem_object *shmem)
130 {
131 	return (shmem->madv > 0) &&
132 		!refcount_read(&shmem->pages_pin_count) && shmem->sgt &&
133 		!shmem->base.dma_buf && !drm_gem_is_imported(&shmem->base);
134 }
135 
136 void drm_gem_shmem_purge_locked(struct drm_gem_shmem_object *shmem);
137 
138 struct sg_table *drm_gem_shmem_get_sg_table(struct drm_gem_shmem_object *shmem);
139 struct sg_table *drm_gem_shmem_get_pages_sgt(struct drm_gem_shmem_object *shmem);
140 
141 void drm_gem_shmem_print_info(const struct drm_gem_shmem_object *shmem,
142 			      struct drm_printer *p, unsigned int indent);
143 
144 extern const struct vm_operations_struct drm_gem_shmem_vm_ops;
145 
146 /*
147  * GEM object functions
148  */
149 
150 /**
151  * drm_gem_shmem_object_free - GEM object function for drm_gem_shmem_free()
152  * @obj: GEM object to free
153  *
154  * This function wraps drm_gem_shmem_free(). Drivers that employ the shmem helpers
155  * should use it as their &drm_gem_object_funcs.free handler.
156  */
157 static inline void drm_gem_shmem_object_free(struct drm_gem_object *obj)
158 {
159 	struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
160 
161 	drm_gem_shmem_free(shmem);
162 }
163 
164 /**
165  * drm_gem_shmem_object_print_info() - Print &drm_gem_shmem_object info for debugfs
166  * @p: DRM printer
167  * @indent: Tab indentation level
168  * @obj: GEM object
169  *
170  * This function wraps drm_gem_shmem_print_info(). Drivers that employ the shmem helpers should
171  * use this function as their &drm_gem_object_funcs.print_info handler.
172  */
173 static inline void drm_gem_shmem_object_print_info(struct drm_printer *p, unsigned int indent,
174 						   const struct drm_gem_object *obj)
175 {
176 	const struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
177 
178 	drm_gem_shmem_print_info(shmem, p, indent);
179 }
180 
181 /**
182  * drm_gem_shmem_object_pin - GEM object function for drm_gem_shmem_pin()
183  * @obj: GEM object
184  *
185  * This function wraps drm_gem_shmem_pin(). Drivers that employ the shmem helpers should
186  * use it as their &drm_gem_object_funcs.pin handler.
187  */
188 static inline int drm_gem_shmem_object_pin(struct drm_gem_object *obj)
189 {
190 	struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
191 
192 	return drm_gem_shmem_pin_locked(shmem);
193 }
194 
195 /**
196  * drm_gem_shmem_object_unpin - GEM object function for drm_gem_shmem_unpin()
197  * @obj: GEM object
198  *
199  * This function wraps drm_gem_shmem_unpin(). Drivers that employ the shmem helpers should
200  * use it as their &drm_gem_object_funcs.unpin handler.
201  */
202 static inline void drm_gem_shmem_object_unpin(struct drm_gem_object *obj)
203 {
204 	struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
205 
206 	drm_gem_shmem_unpin_locked(shmem);
207 }
208 
209 /**
210  * drm_gem_shmem_object_get_sg_table - GEM object function for drm_gem_shmem_get_sg_table()
211  * @obj: GEM object
212  *
213  * This function wraps drm_gem_shmem_get_sg_table(). Drivers that employ the shmem helpers should
214  * use it as their &drm_gem_object_funcs.get_sg_table handler.
215  *
216  * Returns:
217  * A pointer to the scatter/gather table of pinned pages or error pointer on failure.
218  */
219 static inline struct sg_table *drm_gem_shmem_object_get_sg_table(struct drm_gem_object *obj)
220 {
221 	struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
222 
223 	return drm_gem_shmem_get_sg_table(shmem);
224 }
225 
226 /*
227  * drm_gem_shmem_object_vmap - GEM object function for drm_gem_shmem_vmap_locked()
228  * @obj: GEM object
229  * @map: Returns the kernel virtual address of the SHMEM GEM object's backing store.
230  *
231  * This function wraps drm_gem_shmem_vmap_locked(). Drivers that employ the shmem
232  * helpers should use it as their &drm_gem_object_funcs.vmap handler.
233  *
234  * Returns:
235  * 0 on success or a negative error code on failure.
236  */
237 static inline int drm_gem_shmem_object_vmap(struct drm_gem_object *obj,
238 					    struct iosys_map *map)
239 {
240 	struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
241 
242 	return drm_gem_shmem_vmap_locked(shmem, map);
243 }
244 
245 /*
246  * drm_gem_shmem_object_vunmap - GEM object function for drm_gem_shmem_vunmap()
247  * @obj: GEM object
248  * @map: Kernel virtual address where the SHMEM GEM object was mapped
249  *
250  * This function wraps drm_gem_shmem_vunmap_locked(). Drivers that employ the shmem
251  * helpers should use it as their &drm_gem_object_funcs.vunmap handler.
252  */
253 static inline void drm_gem_shmem_object_vunmap(struct drm_gem_object *obj,
254 					       struct iosys_map *map)
255 {
256 	struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
257 
258 	drm_gem_shmem_vunmap_locked(shmem, map);
259 }
260 
261 /**
262  * drm_gem_shmem_object_mmap - GEM object function for drm_gem_shmem_mmap()
263  * @obj: GEM object
264  * @vma: VMA for the area to be mapped
265  *
266  * This function wraps drm_gem_shmem_mmap(). Drivers that employ the shmem helpers should
267  * use it as their &drm_gem_object_funcs.mmap handler.
268  *
269  * Returns:
270  * 0 on success or a negative error code on failure.
271  */
272 static inline int drm_gem_shmem_object_mmap(struct drm_gem_object *obj, struct vm_area_struct *vma)
273 {
274 	struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
275 
276 	return drm_gem_shmem_mmap(shmem, vma);
277 }
278 
279 /*
280  * Driver ops
281  */
282 
283 struct drm_gem_object *
284 drm_gem_shmem_prime_import_sg_table(struct drm_device *dev,
285 				    struct dma_buf_attachment *attach,
286 				    struct sg_table *sgt);
287 int drm_gem_shmem_dumb_create(struct drm_file *file, struct drm_device *dev,
288 			      struct drm_mode_create_dumb *args);
289 struct drm_gem_object *drm_gem_shmem_prime_import_no_map(struct drm_device *dev,
290 							 struct dma_buf *buf);
291 
292 /**
293  * DRM_GEM_SHMEM_DRIVER_OPS - Default shmem GEM operations
294  *
295  * This macro provides a shortcut for setting the shmem GEM operations
296  * in the &drm_driver structure. Drivers that do not require an s/g table
297  * for imported buffers should use this.
298  */
299 #define DRM_GEM_SHMEM_DRIVER_OPS \
300 	.gem_prime_import       = drm_gem_shmem_prime_import_no_map, \
301 	.dumb_create            = drm_gem_shmem_dumb_create
302 
303 /*
304  * Kunit helpers
305  */
306 
307 #if IS_ENABLED(CONFIG_KUNIT)
308 int drm_gem_shmem_vmap(struct drm_gem_shmem_object *shmem, struct iosys_map *map);
309 void drm_gem_shmem_vunmap(struct drm_gem_shmem_object *shmem, struct iosys_map *map);
310 int drm_gem_shmem_madvise(struct drm_gem_shmem_object *shmem, int madv);
311 int drm_gem_shmem_purge(struct drm_gem_shmem_object *shmem);
312 #endif
313 
314 #endif /* __DRM_GEM_SHMEM_HELPER_H__ */
315