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 	unsigned int pages_use_count;
41 
42 	/**
43 	 * @madv: State for madvise
44 	 *
45 	 * 0 is active/inuse.
46 	 * A negative value is the object is purged.
47 	 * Positive values are driver specific and not used by the helpers.
48 	 */
49 	int madv;
50 
51 	/**
52 	 * @madv_list: List entry for madvise tracking
53 	 *
54 	 * Typically used by drivers to track purgeable objects
55 	 */
56 	struct list_head madv_list;
57 
58 	/**
59 	 * @sgt: Scatter/gather table for imported PRIME buffers
60 	 */
61 	struct sg_table *sgt;
62 
63 	/**
64 	 * @vaddr: Kernel virtual address of the backing memory
65 	 */
66 	void *vaddr;
67 
68 	/**
69 	 * @vmap_use_count:
70 	 *
71 	 * Reference count on the virtual address.
72 	 * The address are un-mapped when the count reaches zero.
73 	 */
74 	unsigned int vmap_use_count;
75 
76 	/**
77 	 * @pages_mark_dirty_on_put:
78 	 *
79 	 * Mark pages as dirty when they are put.
80 	 */
81 	bool pages_mark_dirty_on_put : 1;
82 
83 	/**
84 	 * @pages_mark_accessed_on_put:
85 	 *
86 	 * Mark pages as accessed when they are put.
87 	 */
88 	bool pages_mark_accessed_on_put : 1;
89 
90 	/**
91 	 * @map_wc: map object write-combined (instead of using shmem defaults).
92 	 */
93 	bool map_wc : 1;
94 };
95 
96 #define to_drm_gem_shmem_obj(obj) \
97 	container_of(obj, struct drm_gem_shmem_object, base)
98 
99 struct drm_gem_shmem_object *drm_gem_shmem_create(struct drm_device *dev, size_t size);
100 void drm_gem_shmem_free(struct drm_gem_shmem_object *shmem);
101 
102 void drm_gem_shmem_put_pages(struct drm_gem_shmem_object *shmem);
103 int drm_gem_shmem_pin(struct drm_gem_shmem_object *shmem);
104 void drm_gem_shmem_unpin(struct drm_gem_shmem_object *shmem);
105 int drm_gem_shmem_vmap(struct drm_gem_shmem_object *shmem,
106 		       struct iosys_map *map);
107 void drm_gem_shmem_vunmap(struct drm_gem_shmem_object *shmem,
108 			  struct iosys_map *map);
109 int drm_gem_shmem_mmap(struct drm_gem_shmem_object *shmem, struct vm_area_struct *vma);
110 
111 int drm_gem_shmem_madvise(struct drm_gem_shmem_object *shmem, int madv);
112 
113 static inline bool drm_gem_shmem_is_purgeable(struct drm_gem_shmem_object *shmem)
114 {
115 	return (shmem->madv > 0) &&
116 		!shmem->vmap_use_count && shmem->sgt &&
117 		!shmem->base.dma_buf && !shmem->base.import_attach;
118 }
119 
120 void drm_gem_shmem_purge(struct drm_gem_shmem_object *shmem);
121 
122 struct sg_table *drm_gem_shmem_get_sg_table(struct drm_gem_shmem_object *shmem);
123 struct sg_table *drm_gem_shmem_get_pages_sgt(struct drm_gem_shmem_object *shmem);
124 
125 void drm_gem_shmem_print_info(const struct drm_gem_shmem_object *shmem,
126 			      struct drm_printer *p, unsigned int indent);
127 
128 extern const struct vm_operations_struct drm_gem_shmem_vm_ops;
129 
130 /*
131  * GEM object functions
132  */
133 
134 /**
135  * drm_gem_shmem_object_free - GEM object function for drm_gem_shmem_free()
136  * @obj: GEM object to free
137  *
138  * This function wraps drm_gem_shmem_free(). Drivers that employ the shmem helpers
139  * should use it as their &drm_gem_object_funcs.free handler.
140  */
141 static inline void drm_gem_shmem_object_free(struct drm_gem_object *obj)
142 {
143 	struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
144 
145 	drm_gem_shmem_free(shmem);
146 }
147 
148 /**
149  * drm_gem_shmem_object_print_info() - Print &drm_gem_shmem_object info for debugfs
150  * @p: DRM printer
151  * @indent: Tab indentation level
152  * @obj: GEM object
153  *
154  * This function wraps drm_gem_shmem_print_info(). Drivers that employ the shmem helpers should
155  * use this function as their &drm_gem_object_funcs.print_info handler.
156  */
157 static inline void drm_gem_shmem_object_print_info(struct drm_printer *p, unsigned int indent,
158 						   const struct drm_gem_object *obj)
159 {
160 	const struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
161 
162 	drm_gem_shmem_print_info(shmem, p, indent);
163 }
164 
165 /**
166  * drm_gem_shmem_object_pin - GEM object function for drm_gem_shmem_pin()
167  * @obj: GEM object
168  *
169  * This function wraps drm_gem_shmem_pin(). Drivers that employ the shmem helpers should
170  * use it as their &drm_gem_object_funcs.pin handler.
171  */
172 static inline int drm_gem_shmem_object_pin(struct drm_gem_object *obj)
173 {
174 	struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
175 
176 	return drm_gem_shmem_pin(shmem);
177 }
178 
179 /**
180  * drm_gem_shmem_object_unpin - GEM object function for drm_gem_shmem_unpin()
181  * @obj: GEM object
182  *
183  * This function wraps drm_gem_shmem_unpin(). Drivers that employ the shmem helpers should
184  * use it as their &drm_gem_object_funcs.unpin handler.
185  */
186 static inline void drm_gem_shmem_object_unpin(struct drm_gem_object *obj)
187 {
188 	struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
189 
190 	drm_gem_shmem_unpin(shmem);
191 }
192 
193 /**
194  * drm_gem_shmem_object_get_sg_table - GEM object function for drm_gem_shmem_get_sg_table()
195  * @obj: GEM object
196  *
197  * This function wraps drm_gem_shmem_get_sg_table(). Drivers that employ the shmem helpers should
198  * use it as their &drm_gem_object_funcs.get_sg_table handler.
199  *
200  * Returns:
201  * A pointer to the scatter/gather table of pinned pages or error pointer on failure.
202  */
203 static inline struct sg_table *drm_gem_shmem_object_get_sg_table(struct drm_gem_object *obj)
204 {
205 	struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
206 
207 	return drm_gem_shmem_get_sg_table(shmem);
208 }
209 
210 /*
211  * drm_gem_shmem_object_vmap - GEM object function for drm_gem_shmem_vmap()
212  * @obj: GEM object
213  * @map: Returns the kernel virtual address of the SHMEM GEM object's backing store.
214  *
215  * This function wraps drm_gem_shmem_vmap(). Drivers that employ the shmem helpers should
216  * use it as their &drm_gem_object_funcs.vmap handler.
217  *
218  * Returns:
219  * 0 on success or a negative error code on failure.
220  */
221 static inline int drm_gem_shmem_object_vmap(struct drm_gem_object *obj,
222 					    struct iosys_map *map)
223 {
224 	struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
225 
226 	return drm_gem_shmem_vmap(shmem, map);
227 }
228 
229 /*
230  * drm_gem_shmem_object_vunmap - GEM object function for drm_gem_shmem_vunmap()
231  * @obj: GEM object
232  * @map: Kernel virtual address where the SHMEM GEM object was mapped
233  *
234  * This function wraps drm_gem_shmem_vunmap(). Drivers that employ the shmem helpers should
235  * use it as their &drm_gem_object_funcs.vunmap handler.
236  */
237 static inline void drm_gem_shmem_object_vunmap(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 	drm_gem_shmem_vunmap(shmem, map);
243 }
244 
245 /**
246  * drm_gem_shmem_object_mmap - GEM object function for drm_gem_shmem_mmap()
247  * @obj: GEM object
248  * @vma: VMA for the area to be mapped
249  *
250  * This function wraps drm_gem_shmem_mmap(). Drivers that employ the shmem helpers should
251  * use it as their &drm_gem_object_funcs.mmap handler.
252  *
253  * Returns:
254  * 0 on success or a negative error code on failure.
255  */
256 static inline int drm_gem_shmem_object_mmap(struct drm_gem_object *obj, struct vm_area_struct *vma)
257 {
258 	struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
259 
260 	return drm_gem_shmem_mmap(shmem, vma);
261 }
262 
263 /*
264  * Driver ops
265  */
266 
267 struct drm_gem_object *
268 drm_gem_shmem_prime_import_sg_table(struct drm_device *dev,
269 				    struct dma_buf_attachment *attach,
270 				    struct sg_table *sgt);
271 int drm_gem_shmem_dumb_create(struct drm_file *file, struct drm_device *dev,
272 			      struct drm_mode_create_dumb *args);
273 
274 /**
275  * DRM_GEM_SHMEM_DRIVER_OPS - Default shmem GEM operations
276  *
277  * This macro provides a shortcut for setting the shmem GEM operations in
278  * the &drm_driver structure.
279  */
280 #define DRM_GEM_SHMEM_DRIVER_OPS \
281 	.gem_prime_import_sg_table = drm_gem_shmem_prime_import_sg_table, \
282 	.dumb_create		   = drm_gem_shmem_dumb_create
283 
284 #endif /* __DRM_GEM_SHMEM_HELPER_H__ */
285