drm_gem_shmem_helper.h

  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
110int drm_gem_shmem_init(struct drm_device *dev, struct drm_gem_shmem_object *shmem, size_t size);
111struct drm_gem_shmem_object *drm_gem_shmem_create(struct drm_device *dev, size_t size);
112struct drm_gem_shmem_object *drm_gem_shmem_create_with_mnt(struct drm_device *dev,
113							   size_t size,
114							   struct vfsmount *gemfs);
115void drm_gem_shmem_release(struct drm_gem_shmem_object *shmem);
116void drm_gem_shmem_free(struct drm_gem_shmem_object *shmem);
117
118void drm_gem_shmem_put_pages_locked(struct drm_gem_shmem_object *shmem);
119int drm_gem_shmem_pin(struct drm_gem_shmem_object *shmem);
120void drm_gem_shmem_unpin(struct drm_gem_shmem_object *shmem);
121int drm_gem_shmem_vmap_locked(struct drm_gem_shmem_object *shmem,
122			      struct iosys_map *map);
123void drm_gem_shmem_vunmap_locked(struct drm_gem_shmem_object *shmem,
124				 struct iosys_map *map);
125int drm_gem_shmem_mmap(struct drm_gem_shmem_object *shmem, struct vm_area_struct *vma);
126
127int drm_gem_shmem_pin_locked(struct drm_gem_shmem_object *shmem);
128void drm_gem_shmem_unpin_locked(struct drm_gem_shmem_object *shmem);
129
130int drm_gem_shmem_madvise_locked(struct drm_gem_shmem_object *shmem, int madv);
131
132static 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
139void drm_gem_shmem_purge_locked(struct drm_gem_shmem_object *shmem);
140
141struct sg_table *drm_gem_shmem_get_sg_table(struct drm_gem_shmem_object *shmem);
142struct sg_table *drm_gem_shmem_get_pages_sgt(struct drm_gem_shmem_object *shmem);
143
144void drm_gem_shmem_print_info(const struct drm_gem_shmem_object *shmem,
145			      struct drm_printer *p, unsigned int indent);
146
147extern 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 */
160static 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 */
176static 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 */
191static 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 */
205static 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 */
222static 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 */
240static 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 */
256static 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 */
275static 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
286struct drm_gem_object *
287drm_gem_shmem_prime_import_sg_table(struct drm_device *dev,
288				    struct dma_buf_attachment *attach,
289				    struct sg_table *sgt);
290int drm_gem_shmem_dumb_create(struct drm_file *file, struct drm_device *dev,
291			      struct drm_mode_create_dumb *args);
292struct 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/*
307 * Kunit helpers
308 */
309
310#if IS_ENABLED(CONFIG_KUNIT)
311int drm_gem_shmem_vmap(struct drm_gem_shmem_object *shmem, struct iosys_map *map);
312void drm_gem_shmem_vunmap(struct drm_gem_shmem_object *shmem, struct iosys_map *map);
313int drm_gem_shmem_madvise(struct drm_gem_shmem_object *shmem, int madv);
314int drm_gem_shmem_purge(struct drm_gem_shmem_object *shmem);
315#endif
316
317#endif /* __DRM_GEM_SHMEM_HELPER_H__ */