xref: /linux/include/drm/drm_gem_shmem_helper.h (revision 7db28abbea0f7dc1ec4fdfdc149db5fbd9e4c994)
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 void __drm_gem_shmem_free_sgt_locked(struct drm_gem_shmem_object *shmem);
115 
116 void drm_gem_shmem_put_pages_locked(struct drm_gem_shmem_object *shmem);
117 int drm_gem_shmem_pin(struct drm_gem_shmem_object *shmem);
118 void drm_gem_shmem_unpin(struct drm_gem_shmem_object *shmem);
119 int drm_gem_shmem_vmap_locked(struct drm_gem_shmem_object *shmem,
120 			      struct iosys_map *map);
121 void drm_gem_shmem_vunmap_locked(struct drm_gem_shmem_object *shmem,
122 				 struct iosys_map *map);
123 int drm_gem_shmem_mmap(struct drm_gem_shmem_object *shmem, struct vm_area_struct *vma);
124 
125 int drm_gem_shmem_pin_locked(struct drm_gem_shmem_object *shmem);
126 void drm_gem_shmem_unpin_locked(struct drm_gem_shmem_object *shmem);
127 
128 int drm_gem_shmem_madvise_locked(struct drm_gem_shmem_object *shmem, int madv);
129 
130 static inline bool drm_gem_shmem_is_purgeable(struct drm_gem_shmem_object *shmem)
131 {
132 	return (shmem->madv > 0) &&
133 		!refcount_read(&shmem->pages_pin_count) && shmem->sgt &&
134 		!shmem->base.dma_buf && !drm_gem_is_imported(&shmem->base);
135 }
136 
137 void drm_gem_shmem_purge_locked(struct drm_gem_shmem_object *shmem);
138 
139 struct sg_table *drm_gem_shmem_get_sg_table(struct drm_gem_shmem_object *shmem);
140 struct sg_table *drm_gem_shmem_get_pages_sgt(struct drm_gem_shmem_object *shmem);
141 
142 void drm_gem_shmem_print_info(const struct drm_gem_shmem_object *shmem,
143 			      struct drm_printer *p, unsigned int indent);
144 
145 int drm_gem_shmem_create_with_handle(struct drm_file *file_priv,
146 				     struct drm_device *dev, size_t size,
147 				     uint32_t *handle);
148 
149 extern const struct vm_operations_struct drm_gem_shmem_vm_ops;
150 
151 /*
152  * GEM object functions
153  */
154 
155 /**
156  * drm_gem_shmem_object_free - GEM object function for drm_gem_shmem_free()
157  * @obj: GEM object to free
158  *
159  * This function wraps drm_gem_shmem_free(). Drivers that employ the shmem helpers
160  * should use it as their &drm_gem_object_funcs.free handler.
161  */
162 static inline void drm_gem_shmem_object_free(struct drm_gem_object *obj)
163 {
164 	struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
165 
166 	drm_gem_shmem_free(shmem);
167 }
168 
169 /**
170  * drm_gem_shmem_object_print_info() - Print &drm_gem_shmem_object info for debugfs
171  * @p: DRM printer
172  * @indent: Tab indentation level
173  * @obj: GEM object
174  *
175  * This function wraps drm_gem_shmem_print_info(). Drivers that employ the shmem helpers should
176  * use this function as their &drm_gem_object_funcs.print_info handler.
177  */
178 static inline void drm_gem_shmem_object_print_info(struct drm_printer *p, unsigned int indent,
179 						   const struct drm_gem_object *obj)
180 {
181 	const struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
182 
183 	drm_gem_shmem_print_info(shmem, p, indent);
184 }
185 
186 /**
187  * drm_gem_shmem_object_pin - GEM object function for drm_gem_shmem_pin()
188  * @obj: GEM object
189  *
190  * This function wraps drm_gem_shmem_pin(). Drivers that employ the shmem helpers should
191  * use it as their &drm_gem_object_funcs.pin handler.
192  */
193 static inline int drm_gem_shmem_object_pin(struct drm_gem_object *obj)
194 {
195 	struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
196 
197 	return drm_gem_shmem_pin_locked(shmem);
198 }
199 
200 /**
201  * drm_gem_shmem_object_unpin - GEM object function for drm_gem_shmem_unpin()
202  * @obj: GEM object
203  *
204  * This function wraps drm_gem_shmem_unpin(). Drivers that employ the shmem helpers should
205  * use it as their &drm_gem_object_funcs.unpin handler.
206  */
207 static inline void drm_gem_shmem_object_unpin(struct drm_gem_object *obj)
208 {
209 	struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
210 
211 	drm_gem_shmem_unpin_locked(shmem);
212 }
213 
214 /**
215  * drm_gem_shmem_object_get_sg_table - GEM object function for drm_gem_shmem_get_sg_table()
216  * @obj: GEM object
217  *
218  * This function wraps drm_gem_shmem_get_sg_table(). Drivers that employ the shmem helpers should
219  * use it as their &drm_gem_object_funcs.get_sg_table handler.
220  *
221  * Returns:
222  * A pointer to the scatter/gather table of pinned pages or error pointer on failure.
223  */
224 static inline struct sg_table *drm_gem_shmem_object_get_sg_table(struct drm_gem_object *obj)
225 {
226 	struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
227 
228 	return drm_gem_shmem_get_sg_table(shmem);
229 }
230 
231 /*
232  * drm_gem_shmem_object_vmap - GEM object function for drm_gem_shmem_vmap_locked()
233  * @obj: GEM object
234  * @map: Returns the kernel virtual address of the SHMEM GEM object's backing store.
235  *
236  * This function wraps drm_gem_shmem_vmap_locked(). Drivers that employ the shmem
237  * helpers should use it as their &drm_gem_object_funcs.vmap handler.
238  *
239  * Returns:
240  * 0 on success or a negative error code on failure.
241  */
242 static inline int drm_gem_shmem_object_vmap(struct drm_gem_object *obj,
243 					    struct iosys_map *map)
244 {
245 	struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
246 
247 	return drm_gem_shmem_vmap_locked(shmem, map);
248 }
249 
250 /*
251  * drm_gem_shmem_object_vunmap - GEM object function for drm_gem_shmem_vunmap()
252  * @obj: GEM object
253  * @map: Kernel virtual address where the SHMEM GEM object was mapped
254  *
255  * This function wraps drm_gem_shmem_vunmap_locked(). Drivers that employ the shmem
256  * helpers should use it as their &drm_gem_object_funcs.vunmap handler.
257  */
258 static inline void drm_gem_shmem_object_vunmap(struct drm_gem_object *obj,
259 					       struct iosys_map *map)
260 {
261 	struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
262 
263 	drm_gem_shmem_vunmap_locked(shmem, map);
264 }
265 
266 /**
267  * drm_gem_shmem_object_mmap - GEM object function for drm_gem_shmem_mmap()
268  * @obj: GEM object
269  * @vma: VMA for the area to be mapped
270  *
271  * This function wraps drm_gem_shmem_mmap(). Drivers that employ the shmem helpers should
272  * use it as their &drm_gem_object_funcs.mmap handler.
273  *
274  * Returns:
275  * 0 on success or a negative error code on failure.
276  */
277 static inline int drm_gem_shmem_object_mmap(struct drm_gem_object *obj, struct vm_area_struct *vma)
278 {
279 	struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
280 
281 	return drm_gem_shmem_mmap(shmem, vma);
282 }
283 
284 /*
285  * Driver ops
286  */
287 
288 struct drm_gem_object *
289 drm_gem_shmem_prime_import_sg_table(struct drm_device *dev,
290 				    struct dma_buf_attachment *attach,
291 				    struct sg_table *sgt);
292 int drm_gem_shmem_dumb_create(struct drm_file *file, struct drm_device *dev,
293 			      struct drm_mode_create_dumb *args);
294 struct drm_gem_object *drm_gem_shmem_prime_import_no_map(struct drm_device *dev,
295 							 struct dma_buf *buf);
296 
297 /**
298  * DRM_GEM_SHMEM_DRIVER_OPS - Default shmem GEM operations
299  *
300  * This macro provides a shortcut for setting the shmem GEM operations
301  * in the &drm_driver structure. Drivers that do not require an s/g table
302  * for imported buffers should use this.
303  */
304 #define DRM_GEM_SHMEM_DRIVER_OPS \
305 	.gem_prime_import       = drm_gem_shmem_prime_import_no_map, \
306 	.dumb_create            = drm_gem_shmem_dumb_create
307 
308 /*
309  * Kunit helpers
310  */
311 
312 #if IS_ENABLED(CONFIG_KUNIT)
313 int drm_gem_shmem_vmap(struct drm_gem_shmem_object *shmem, struct iosys_map *map);
314 void drm_gem_shmem_vunmap(struct drm_gem_shmem_object *shmem, struct iosys_map *map);
315 int drm_gem_shmem_madvise(struct drm_gem_shmem_object *shmem, int madv);
316 int drm_gem_shmem_purge(struct drm_gem_shmem_object *shmem);
317 #endif
318 
319 #endif /* __DRM_GEM_SHMEM_HELPER_H__ */
320