xref: /linux/include/drm/drm_gem_shmem_helper.h (revision f6e8dc9edf963dbc99085e54f6ced6da9daa6100)
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 struct drm_gem_shmem_object *drm_gem_shmem_create_with_mnt(struct drm_device *dev,
113 							   size_t size,
114 							   struct vfsmount *gemfs);
115 void drm_gem_shmem_release(struct drm_gem_shmem_object *shmem);
116 void drm_gem_shmem_free(struct drm_gem_shmem_object *shmem);
117 
118 void drm_gem_shmem_put_pages_locked(struct drm_gem_shmem_object *shmem);
119 int drm_gem_shmem_pin(struct drm_gem_shmem_object *shmem);
120 void drm_gem_shmem_unpin(struct drm_gem_shmem_object *shmem);
121 int drm_gem_shmem_vmap_locked(struct drm_gem_shmem_object *shmem,
122 			      struct iosys_map *map);
123 void drm_gem_shmem_vunmap_locked(struct drm_gem_shmem_object *shmem,
124 				 struct iosys_map *map);
125 int drm_gem_shmem_mmap(struct drm_gem_shmem_object *shmem, struct vm_area_struct *vma);
126 
127 int drm_gem_shmem_pin_locked(struct drm_gem_shmem_object *shmem);
128 void drm_gem_shmem_unpin_locked(struct drm_gem_shmem_object *shmem);
129 
130 int drm_gem_shmem_madvise_locked(struct drm_gem_shmem_object *shmem, int madv);
131 
132 static inline bool drm_gem_shmem_is_purgeable(struct drm_gem_shmem_object *shmem)
133 {
134 	return (shmem->madv > 0) &&
135 		!refcount_read(&shmem->pages_pin_count) && shmem->sgt &&
136 		!shmem->base.dma_buf && !drm_gem_is_imported(&shmem->base);
137 }
138 
139 void drm_gem_shmem_purge_locked(struct drm_gem_shmem_object *shmem);
140 
141 struct sg_table *drm_gem_shmem_get_sg_table(struct drm_gem_shmem_object *shmem);
142 struct sg_table *drm_gem_shmem_get_pages_sgt(struct drm_gem_shmem_object *shmem);
143 
144 void drm_gem_shmem_print_info(const struct drm_gem_shmem_object *shmem,
145 			      struct drm_printer *p, unsigned int indent);
146 
147 extern const struct vm_operations_struct drm_gem_shmem_vm_ops;
148 
149 /*
150  * GEM object functions
151  */
152 
153 /**
154  * drm_gem_shmem_object_free - GEM object function for drm_gem_shmem_free()
155  * @obj: GEM object to free
156  *
157  * This function wraps drm_gem_shmem_free(). Drivers that employ the shmem helpers
158  * should use it as their &drm_gem_object_funcs.free handler.
159  */
160 static inline void drm_gem_shmem_object_free(struct drm_gem_object *obj)
161 {
162 	struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
163 
164 	drm_gem_shmem_free(shmem);
165 }
166 
167 /**
168  * drm_gem_shmem_object_print_info() - Print &drm_gem_shmem_object info for debugfs
169  * @p: DRM printer
170  * @indent: Tab indentation level
171  * @obj: GEM object
172  *
173  * This function wraps drm_gem_shmem_print_info(). Drivers that employ the shmem helpers should
174  * use this function as their &drm_gem_object_funcs.print_info handler.
175  */
176 static inline void drm_gem_shmem_object_print_info(struct drm_printer *p, unsigned int indent,
177 						   const struct drm_gem_object *obj)
178 {
179 	const struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
180 
181 	drm_gem_shmem_print_info(shmem, p, indent);
182 }
183 
184 /**
185  * drm_gem_shmem_object_pin - GEM object function for drm_gem_shmem_pin()
186  * @obj: GEM object
187  *
188  * This function wraps drm_gem_shmem_pin(). Drivers that employ the shmem helpers should
189  * use it as their &drm_gem_object_funcs.pin handler.
190  */
191 static inline int drm_gem_shmem_object_pin(struct drm_gem_object *obj)
192 {
193 	struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
194 
195 	return drm_gem_shmem_pin_locked(shmem);
196 }
197 
198 /**
199  * drm_gem_shmem_object_unpin - GEM object function for drm_gem_shmem_unpin()
200  * @obj: GEM object
201  *
202  * This function wraps drm_gem_shmem_unpin(). Drivers that employ the shmem helpers should
203  * use it as their &drm_gem_object_funcs.unpin handler.
204  */
205 static inline void drm_gem_shmem_object_unpin(struct drm_gem_object *obj)
206 {
207 	struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
208 
209 	drm_gem_shmem_unpin_locked(shmem);
210 }
211 
212 /**
213  * drm_gem_shmem_object_get_sg_table - GEM object function for drm_gem_shmem_get_sg_table()
214  * @obj: GEM object
215  *
216  * This function wraps drm_gem_shmem_get_sg_table(). Drivers that employ the shmem helpers should
217  * use it as their &drm_gem_object_funcs.get_sg_table handler.
218  *
219  * Returns:
220  * A pointer to the scatter/gather table of pinned pages or error pointer on failure.
221  */
222 static inline struct sg_table *drm_gem_shmem_object_get_sg_table(struct drm_gem_object *obj)
223 {
224 	struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
225 
226 	return drm_gem_shmem_get_sg_table(shmem);
227 }
228 
229 /*
230  * drm_gem_shmem_object_vmap - GEM object function for drm_gem_shmem_vmap_locked()
231  * @obj: GEM object
232  * @map: Returns the kernel virtual address of the SHMEM GEM object's backing store.
233  *
234  * This function wraps drm_gem_shmem_vmap_locked(). Drivers that employ the shmem
235  * helpers should use it as their &drm_gem_object_funcs.vmap handler.
236  *
237  * Returns:
238  * 0 on success or a negative error code on failure.
239  */
240 static inline int drm_gem_shmem_object_vmap(struct drm_gem_object *obj,
241 					    struct iosys_map *map)
242 {
243 	struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
244 
245 	return drm_gem_shmem_vmap_locked(shmem, map);
246 }
247 
248 /*
249  * drm_gem_shmem_object_vunmap - GEM object function for drm_gem_shmem_vunmap()
250  * @obj: GEM object
251  * @map: Kernel virtual address where the SHMEM GEM object was mapped
252  *
253  * This function wraps drm_gem_shmem_vunmap_locked(). Drivers that employ the shmem
254  * helpers should use it as their &drm_gem_object_funcs.vunmap handler.
255  */
256 static inline void drm_gem_shmem_object_vunmap(struct drm_gem_object *obj,
257 					       struct iosys_map *map)
258 {
259 	struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
260 
261 	drm_gem_shmem_vunmap_locked(shmem, map);
262 }
263 
264 /**
265  * drm_gem_shmem_object_mmap - GEM object function for drm_gem_shmem_mmap()
266  * @obj: GEM object
267  * @vma: VMA for the area to be mapped
268  *
269  * This function wraps drm_gem_shmem_mmap(). Drivers that employ the shmem helpers should
270  * use it as their &drm_gem_object_funcs.mmap handler.
271  *
272  * Returns:
273  * 0 on success or a negative error code on failure.
274  */
275 static inline int drm_gem_shmem_object_mmap(struct drm_gem_object *obj, struct vm_area_struct *vma)
276 {
277 	struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
278 
279 	return drm_gem_shmem_mmap(shmem, vma);
280 }
281 
282 /*
283  * Driver ops
284  */
285 
286 struct drm_gem_object *
287 drm_gem_shmem_prime_import_sg_table(struct drm_device *dev,
288 				    struct dma_buf_attachment *attach,
289 				    struct sg_table *sgt);
290 int drm_gem_shmem_dumb_create(struct drm_file *file, struct drm_device *dev,
291 			      struct drm_mode_create_dumb *args);
292 struct drm_gem_object *drm_gem_shmem_prime_import_no_map(struct drm_device *dev,
293 							 struct dma_buf *buf);
294 
295 /**
296  * DRM_GEM_SHMEM_DRIVER_OPS - Default shmem GEM operations
297  *
298  * This macro provides a shortcut for setting the shmem GEM operations
299  * in the &drm_driver structure. Drivers that do not require an s/g table
300  * for imported buffers should use this.
301  */
302 #define DRM_GEM_SHMEM_DRIVER_OPS \
303 	.gem_prime_import       = drm_gem_shmem_prime_import_no_map, \
304 	.dumb_create            = drm_gem_shmem_dumb_create
305 
306 #endif /* __DRM_GEM_SHMEM_HELPER_H__ */
307