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_lock: Protects the page table and use count
 31	 */
 32	struct mutex pages_lock;
 33
 34	/**
 35	 * @pages: Page table
 36	 */
 37	struct page **pages;
 38
 39	/**
 40	 * @pages_use_count:
 41	 *
 42	 * Reference count on the pages table.
 43	 * The pages are put when the count reaches zero.
 44	 */
 45	unsigned int pages_use_count;
 46
 47	/**
 48	 * @madv: State for madvise
 49	 *
 50	 * 0 is active/inuse.
 51	 * A negative value is the object is purged.
 52	 * Positive values are driver specific and not used by the helpers.
 53	 */
 54	int madv;
 55
 56	/**
 57	 * @madv_list: List entry for madvise tracking
 58	 *
 59	 * Typically used by drivers to track purgeable objects
 60	 */
 61	struct list_head madv_list;
 62
 63	/**
 64	 * @pages_mark_dirty_on_put:
 65	 *
 66	 * Mark pages as dirty when they are put.
 67	 */
 68	unsigned int pages_mark_dirty_on_put    : 1;
 69
 70	/**
 71	 * @pages_mark_accessed_on_put:
 72	 *
 73	 * Mark pages as accessed when they are put.
 74	 */
 75	unsigned int pages_mark_accessed_on_put : 1;
 76
 77	/**
 78	 * @sgt: Scatter/gather table for imported PRIME buffers
 79	 */
 80	struct sg_table *sgt;
 81
 82	/**
 83	 * @vmap_lock: Protects the vmap address and use count
 84	 */
 85	struct mutex vmap_lock;
 86
 87	/**
 88	 * @vaddr: Kernel virtual address of the backing memory
 89	 */
 90	void *vaddr;
 91
 92	/**
 93	 * @vmap_use_count:
 94	 *
 95	 * Reference count on the virtual address.
 96	 * The address are un-mapped when the count reaches zero.
 97	 */
 98	unsigned int vmap_use_count;
 99
100	/**
101	 * @map_wc: map object write-combined (instead of using shmem defaults).
102	 */
103	bool map_wc;
104};
105
106#define to_drm_gem_shmem_obj(obj) \
107	container_of(obj, struct drm_gem_shmem_object, base)
108
109struct drm_gem_shmem_object *drm_gem_shmem_create(struct drm_device *dev, size_t size);
110void drm_gem_shmem_free(struct drm_gem_shmem_object *shmem);
111
112int drm_gem_shmem_get_pages(struct drm_gem_shmem_object *shmem);
113void drm_gem_shmem_put_pages(struct drm_gem_shmem_object *shmem);
114int drm_gem_shmem_pin(struct drm_gem_shmem_object *shmem);
115void drm_gem_shmem_unpin(struct drm_gem_shmem_object *shmem);
116int drm_gem_shmem_vmap(struct drm_gem_shmem_object *shmem,
117		       struct iosys_map *map);
118void drm_gem_shmem_vunmap(struct drm_gem_shmem_object *shmem,
119			  struct iosys_map *map);
120int drm_gem_shmem_mmap(struct drm_gem_shmem_object *shmem, struct vm_area_struct *vma);
121
122int drm_gem_shmem_madvise(struct drm_gem_shmem_object *shmem, int madv);
123
124static inline bool drm_gem_shmem_is_purgeable(struct drm_gem_shmem_object *shmem)
125{
126	return (shmem->madv > 0) &&
127		!shmem->vmap_use_count && shmem->sgt &&
128		!shmem->base.dma_buf && !shmem->base.import_attach;
129}
130
131void drm_gem_shmem_purge_locked(struct drm_gem_shmem_object *shmem);
132bool drm_gem_shmem_purge(struct drm_gem_shmem_object *shmem);
133
134struct sg_table *drm_gem_shmem_get_sg_table(struct drm_gem_shmem_object *shmem);
135struct sg_table *drm_gem_shmem_get_pages_sgt(struct drm_gem_shmem_object *shmem);
136
137void drm_gem_shmem_print_info(const struct drm_gem_shmem_object *shmem,
138			      struct drm_printer *p, unsigned int indent);
139
140extern const struct vm_operations_struct drm_gem_shmem_vm_ops;
141
142/*
143 * GEM object functions
144 */
145
146/**
147 * drm_gem_shmem_object_free - GEM object function for drm_gem_shmem_free()
148 * @obj: GEM object to free
149 *
150 * This function wraps drm_gem_shmem_free(). Drivers that employ the shmem helpers
151 * should use it as their &drm_gem_object_funcs.free handler.
152 */
153static inline void drm_gem_shmem_object_free(struct drm_gem_object *obj)
154{
155	struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
156
157	drm_gem_shmem_free(shmem);
158}
159
160/**
161 * drm_gem_shmem_object_print_info() - Print &drm_gem_shmem_object info for debugfs
162 * @p: DRM printer
163 * @indent: Tab indentation level
164 * @obj: GEM object
165 *
166 * This function wraps drm_gem_shmem_print_info(). Drivers that employ the shmem helpers should
167 * use this function as their &drm_gem_object_funcs.print_info handler.
168 */
169static inline void drm_gem_shmem_object_print_info(struct drm_printer *p, unsigned int indent,
170						   const struct drm_gem_object *obj)
171{
172	const struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
173
174	drm_gem_shmem_print_info(shmem, p, indent);
175}
176
177/**
178 * drm_gem_shmem_object_pin - GEM object function for drm_gem_shmem_pin()
179 * @obj: GEM object
180 *
181 * This function wraps drm_gem_shmem_pin(). Drivers that employ the shmem helpers should
182 * use it as their &drm_gem_object_funcs.pin handler.
183 */
184static inline int drm_gem_shmem_object_pin(struct drm_gem_object *obj)
185{
186	struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
187
188	return drm_gem_shmem_pin(shmem);
189}
190
191/**
192 * drm_gem_shmem_object_unpin - GEM object function for drm_gem_shmem_unpin()
193 * @obj: GEM object
194 *
195 * This function wraps drm_gem_shmem_unpin(). Drivers that employ the shmem helpers should
196 * use it as their &drm_gem_object_funcs.unpin handler.
197 */
198static inline void drm_gem_shmem_object_unpin(struct drm_gem_object *obj)
199{
200	struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
201
202	drm_gem_shmem_unpin(shmem);
203}
204
205/**
206 * drm_gem_shmem_object_get_sg_table - GEM object function for drm_gem_shmem_get_sg_table()
207 * @obj: GEM object
208 *
209 * This function wraps drm_gem_shmem_get_sg_table(). Drivers that employ the shmem helpers should
210 * use it as their &drm_gem_object_funcs.get_sg_table handler.
211 *
212 * Returns:
213 * A pointer to the scatter/gather table of pinned pages or error pointer on failure.
214 */
215static inline struct sg_table *drm_gem_shmem_object_get_sg_table(struct drm_gem_object *obj)
216{
217	struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
218
219	return drm_gem_shmem_get_sg_table(shmem);
220}
221
222/*
223 * drm_gem_shmem_object_vmap - GEM object function for drm_gem_shmem_vmap()
224 * @obj: GEM object
225 * @map: Returns the kernel virtual address of the SHMEM GEM object's backing store.
226 *
227 * This function wraps drm_gem_shmem_vmap(). Drivers that employ the shmem helpers should
228 * use it as their &drm_gem_object_funcs.vmap handler.
229 *
230 * Returns:
231 * 0 on success or a negative error code on failure.
232 */
233static inline int drm_gem_shmem_object_vmap(struct drm_gem_object *obj,
234					    struct iosys_map *map)
235{
236	struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
237
238	return drm_gem_shmem_vmap(shmem, map);
239}
240
241/*
242 * drm_gem_shmem_object_vunmap - GEM object function for drm_gem_shmem_vunmap()
243 * @obj: GEM object
244 * @map: Kernel virtual address where the SHMEM GEM object was mapped
245 *
246 * This function wraps drm_gem_shmem_vunmap(). Drivers that employ the shmem helpers should
247 * use it as their &drm_gem_object_funcs.vunmap handler.
248 */
249static inline void drm_gem_shmem_object_vunmap(struct drm_gem_object *obj,
250					       struct iosys_map *map)
251{
252	struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
253
254	drm_gem_shmem_vunmap(shmem, map);
255}
256
257/**
258 * drm_gem_shmem_object_mmap - GEM object function for drm_gem_shmem_mmap()
259 * @obj: GEM object
260 * @vma: VMA for the area to be mapped
261 *
262 * This function wraps drm_gem_shmem_mmap(). Drivers that employ the shmem helpers should
263 * use it as their &drm_gem_object_funcs.mmap handler.
264 *
265 * Returns:
266 * 0 on success or a negative error code on failure.
267 */
268static inline int drm_gem_shmem_object_mmap(struct drm_gem_object *obj, struct vm_area_struct *vma)
269{
270	struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
271
272	return drm_gem_shmem_mmap(shmem, vma);
273}
274
275/*
276 * Driver ops
277 */
278
279struct drm_gem_object *
280drm_gem_shmem_prime_import_sg_table(struct drm_device *dev,
281				    struct dma_buf_attachment *attach,
282				    struct sg_table *sgt);
283int drm_gem_shmem_dumb_create(struct drm_file *file, struct drm_device *dev,
284			      struct drm_mode_create_dumb *args);
285
286/**
287 * DRM_GEM_SHMEM_DRIVER_OPS - Default shmem GEM operations
288 *
289 * This macro provides a shortcut for setting the shmem GEM operations in
290 * the &drm_driver structure.
291 */
292#define DRM_GEM_SHMEM_DRIVER_OPS \
293	.prime_handle_to_fd	= drm_gem_prime_handle_to_fd, \
294	.prime_fd_to_handle	= drm_gem_prime_fd_to_handle, \
295	.gem_prime_import_sg_table = drm_gem_shmem_prime_import_sg_table, \
296	.gem_prime_mmap		= drm_gem_prime_mmap, \
297	.dumb_create		= drm_gem_shmem_dumb_create
298
299#endif /* __DRM_GEM_SHMEM_HELPER_H__ */