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
15struct dma_buf_attachment;
16struct drm_mode_create_dumb;
17struct drm_printer;
18struct sg_table;
19
20/**
21 * struct drm_gem_shmem_object - GEM object backed by shmem
22 */
23struct 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
110struct drm_gem_shmem_object *drm_gem_shmem_create(struct drm_device *dev, size_t size);
111struct drm_gem_shmem_object *drm_gem_shmem_create_with_mnt(struct drm_device *dev,
112 size_t size,
113 struct vfsmount *gemfs);
114void drm_gem_shmem_free(struct drm_gem_shmem_object *shmem);
115
116void drm_gem_shmem_put_pages_locked(struct drm_gem_shmem_object *shmem);
117int drm_gem_shmem_pin(struct drm_gem_shmem_object *shmem);
118void drm_gem_shmem_unpin(struct drm_gem_shmem_object *shmem);
119int drm_gem_shmem_vmap_locked(struct drm_gem_shmem_object *shmem,
120 struct iosys_map *map);
121void drm_gem_shmem_vunmap_locked(struct drm_gem_shmem_object *shmem,
122 struct iosys_map *map);
123int drm_gem_shmem_mmap(struct drm_gem_shmem_object *shmem, struct vm_area_struct *vma);
124
125int drm_gem_shmem_pin_locked(struct drm_gem_shmem_object *shmem);
126void drm_gem_shmem_unpin_locked(struct drm_gem_shmem_object *shmem);
127
128int drm_gem_shmem_madvise_locked(struct drm_gem_shmem_object *shmem, int madv);
129
130static inline bool drm_gem_shmem_is_purgeable(struct drm_gem_shmem_object *shmem)
131{
132 return (shmem->madv > 0) &&
133 !refcount_read(r: &shmem->pages_pin_count) && shmem->sgt &&
134 !shmem->base.dma_buf && !drm_gem_is_imported(obj: &shmem->base);
135}
136
137void drm_gem_shmem_purge_locked(struct drm_gem_shmem_object *shmem);
138
139struct sg_table *drm_gem_shmem_get_sg_table(struct drm_gem_shmem_object *shmem);
140struct sg_table *drm_gem_shmem_get_pages_sgt(struct drm_gem_shmem_object *shmem);
141
142void drm_gem_shmem_print_info(const struct drm_gem_shmem_object *shmem,
143 struct drm_printer *p, unsigned int indent);
144
145extern const struct vm_operations_struct drm_gem_shmem_vm_ops;
146
147/*
148 * GEM object functions
149 */
150
151/**
152 * drm_gem_shmem_object_free - GEM object function for drm_gem_shmem_free()
153 * @obj: GEM object to free
154 *
155 * This function wraps drm_gem_shmem_free(). Drivers that employ the shmem helpers
156 * should use it as their &drm_gem_object_funcs.free handler.
157 */
158static inline void drm_gem_shmem_object_free(struct drm_gem_object *obj)
159{
160 struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
161
162 drm_gem_shmem_free(shmem);
163}
164
165/**
166 * drm_gem_shmem_object_print_info() - Print &drm_gem_shmem_object info for debugfs
167 * @p: DRM printer
168 * @indent: Tab indentation level
169 * @obj: GEM object
170 *
171 * This function wraps drm_gem_shmem_print_info(). Drivers that employ the shmem helpers should
172 * use this function as their &drm_gem_object_funcs.print_info handler.
173 */
174static inline void drm_gem_shmem_object_print_info(struct drm_printer *p, unsigned int indent,
175 const struct drm_gem_object *obj)
176{
177 const struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
178
179 drm_gem_shmem_print_info(shmem, p, indent);
180}
181
182/**
183 * drm_gem_shmem_object_pin - GEM object function for drm_gem_shmem_pin()
184 * @obj: GEM object
185 *
186 * This function wraps drm_gem_shmem_pin(). Drivers that employ the shmem helpers should
187 * use it as their &drm_gem_object_funcs.pin handler.
188 */
189static inline int drm_gem_shmem_object_pin(struct drm_gem_object *obj)
190{
191 struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
192
193 return drm_gem_shmem_pin_locked(shmem);
194}
195
196/**
197 * drm_gem_shmem_object_unpin - GEM object function for drm_gem_shmem_unpin()
198 * @obj: GEM object
199 *
200 * This function wraps drm_gem_shmem_unpin(). Drivers that employ the shmem helpers should
201 * use it as their &drm_gem_object_funcs.unpin handler.
202 */
203static inline void drm_gem_shmem_object_unpin(struct drm_gem_object *obj)
204{
205 struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
206
207 drm_gem_shmem_unpin_locked(shmem);
208}
209
210/**
211 * drm_gem_shmem_object_get_sg_table - GEM object function for drm_gem_shmem_get_sg_table()
212 * @obj: GEM object
213 *
214 * This function wraps drm_gem_shmem_get_sg_table(). Drivers that employ the shmem helpers should
215 * use it as their &drm_gem_object_funcs.get_sg_table handler.
216 *
217 * Returns:
218 * A pointer to the scatter/gather table of pinned pages or error pointer on failure.
219 */
220static inline struct sg_table *drm_gem_shmem_object_get_sg_table(struct drm_gem_object *obj)
221{
222 struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
223
224 return drm_gem_shmem_get_sg_table(shmem);
225}
226
227/*
228 * drm_gem_shmem_object_vmap - GEM object function for drm_gem_shmem_vmap_locked()
229 * @obj: GEM object
230 * @map: Returns the kernel virtual address of the SHMEM GEM object's backing store.
231 *
232 * This function wraps drm_gem_shmem_vmap_locked(). Drivers that employ the shmem
233 * helpers should use it as their &drm_gem_object_funcs.vmap handler.
234 *
235 * Returns:
236 * 0 on success or a negative error code on failure.
237 */
238static inline int drm_gem_shmem_object_vmap(struct drm_gem_object *obj,
239 struct iosys_map *map)
240{
241 struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
242
243 return drm_gem_shmem_vmap_locked(shmem, map);
244}
245
246/*
247 * drm_gem_shmem_object_vunmap - GEM object function for drm_gem_shmem_vunmap()
248 * @obj: GEM object
249 * @map: Kernel virtual address where the SHMEM GEM object was mapped
250 *
251 * This function wraps drm_gem_shmem_vunmap_locked(). Drivers that employ the shmem
252 * helpers should use it as their &drm_gem_object_funcs.vunmap handler.
253 */
254static inline void drm_gem_shmem_object_vunmap(struct drm_gem_object *obj,
255 struct iosys_map *map)
256{
257 struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
258
259 drm_gem_shmem_vunmap_locked(shmem, map);
260}
261
262/**
263 * drm_gem_shmem_object_mmap - GEM object function for drm_gem_shmem_mmap()
264 * @obj: GEM object
265 * @vma: VMA for the area to be mapped
266 *
267 * This function wraps drm_gem_shmem_mmap(). Drivers that employ the shmem helpers should
268 * use it as their &drm_gem_object_funcs.mmap handler.
269 *
270 * Returns:
271 * 0 on success or a negative error code on failure.
272 */
273static inline int drm_gem_shmem_object_mmap(struct drm_gem_object *obj, struct vm_area_struct *vma)
274{
275 struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
276
277 return drm_gem_shmem_mmap(shmem, vma);
278}
279
280/*
281 * Driver ops
282 */
283
284struct drm_gem_object *
285drm_gem_shmem_prime_import_sg_table(struct drm_device *dev,
286 struct dma_buf_attachment *attach,
287 struct sg_table *sgt);
288int drm_gem_shmem_dumb_create(struct drm_file *file, struct drm_device *dev,
289 struct drm_mode_create_dumb *args);
290struct drm_gem_object *drm_gem_shmem_prime_import_no_map(struct drm_device *dev,
291 struct dma_buf *buf);
292
293/**
294 * DRM_GEM_SHMEM_DRIVER_OPS - Default shmem GEM operations
295 *
296 * This macro provides a shortcut for setting the shmem GEM operations
297 * in the &drm_driver structure. Drivers that do not require an s/g table
298 * for imported buffers should use this.
299 */
300#define DRM_GEM_SHMEM_DRIVER_OPS \
301 .gem_prime_import = drm_gem_shmem_prime_import_no_map, \
302 .dumb_create = drm_gem_shmem_dumb_create
303
304#endif /* __DRM_GEM_SHMEM_HELPER_H__ */
305