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	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
 99struct drm_gem_shmem_object *drm_gem_shmem_create(struct drm_device *dev, size_t size);
100struct drm_gem_shmem_object *drm_gem_shmem_create_with_mnt(struct drm_device *dev,
101							   size_t size,
102							   struct vfsmount *gemfs);
103void drm_gem_shmem_free(struct drm_gem_shmem_object *shmem);
104
105void drm_gem_shmem_put_pages(struct drm_gem_shmem_object *shmem);
106int drm_gem_shmem_pin(struct drm_gem_shmem_object *shmem);
107void drm_gem_shmem_unpin(struct drm_gem_shmem_object *shmem);
108int drm_gem_shmem_vmap(struct drm_gem_shmem_object *shmem,
109		       struct iosys_map *map);
110void drm_gem_shmem_vunmap(struct drm_gem_shmem_object *shmem,
111			  struct iosys_map *map);
112int drm_gem_shmem_mmap(struct drm_gem_shmem_object *shmem, struct vm_area_struct *vma);
113
114int drm_gem_shmem_pin_locked(struct drm_gem_shmem_object *shmem);
115void drm_gem_shmem_unpin_locked(struct drm_gem_shmem_object *shmem);
116
117int drm_gem_shmem_madvise(struct drm_gem_shmem_object *shmem, int madv);
118
119static inline bool drm_gem_shmem_is_purgeable(struct drm_gem_shmem_object *shmem)
120{
121	return (shmem->madv > 0) &&
122		!shmem->vmap_use_count && shmem->sgt &&
123		!shmem->base.dma_buf && !shmem->base.import_attach;
124}
125
126void drm_gem_shmem_purge(struct drm_gem_shmem_object *shmem);
127
128struct sg_table *drm_gem_shmem_get_sg_table(struct drm_gem_shmem_object *shmem);
129struct sg_table *drm_gem_shmem_get_pages_sgt(struct drm_gem_shmem_object *shmem);
130
131void drm_gem_shmem_print_info(const struct drm_gem_shmem_object *shmem,
132			      struct drm_printer *p, unsigned int indent);
133
134extern const struct vm_operations_struct drm_gem_shmem_vm_ops;
135
136/*
137 * GEM object functions
138 */
139
140/**
141 * drm_gem_shmem_object_free - GEM object function for drm_gem_shmem_free()
142 * @obj: GEM object to free
143 *
144 * This function wraps drm_gem_shmem_free(). Drivers that employ the shmem helpers
145 * should use it as their &drm_gem_object_funcs.free handler.
146 */
147static inline void drm_gem_shmem_object_free(struct drm_gem_object *obj)
148{
149	struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
150
151	drm_gem_shmem_free(shmem);
152}
153
154/**
155 * drm_gem_shmem_object_print_info() - Print &drm_gem_shmem_object info for debugfs
156 * @p: DRM printer
157 * @indent: Tab indentation level
158 * @obj: GEM object
159 *
160 * This function wraps drm_gem_shmem_print_info(). Drivers that employ the shmem helpers should
161 * use this function as their &drm_gem_object_funcs.print_info handler.
162 */
163static inline void drm_gem_shmem_object_print_info(struct drm_printer *p, unsigned int indent,
164						   const struct drm_gem_object *obj)
165{
166	const struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
167
168	drm_gem_shmem_print_info(shmem, p, indent);
169}
170
171/**
172 * drm_gem_shmem_object_pin - GEM object function for drm_gem_shmem_pin()
173 * @obj: GEM object
174 *
175 * This function wraps drm_gem_shmem_pin(). Drivers that employ the shmem helpers should
176 * use it as their &drm_gem_object_funcs.pin handler.
177 */
178static inline int drm_gem_shmem_object_pin(struct drm_gem_object *obj)
179{
180	struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
181
182	return drm_gem_shmem_pin_locked(shmem);
183}
184
185/**
186 * drm_gem_shmem_object_unpin - GEM object function for drm_gem_shmem_unpin()
187 * @obj: GEM object
188 *
189 * This function wraps drm_gem_shmem_unpin(). Drivers that employ the shmem helpers should
190 * use it as their &drm_gem_object_funcs.unpin handler.
191 */
192static inline void drm_gem_shmem_object_unpin(struct drm_gem_object *obj)
193{
194	struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
195
196	drm_gem_shmem_unpin_locked(shmem);
197}
198
199/**
200 * drm_gem_shmem_object_get_sg_table - GEM object function for drm_gem_shmem_get_sg_table()
201 * @obj: GEM object
202 *
203 * This function wraps drm_gem_shmem_get_sg_table(). Drivers that employ the shmem helpers should
204 * use it as their &drm_gem_object_funcs.get_sg_table handler.
205 *
206 * Returns:
207 * A pointer to the scatter/gather table of pinned pages or error pointer on failure.
208 */
209static inline struct sg_table *drm_gem_shmem_object_get_sg_table(struct drm_gem_object *obj)
210{
211	struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
212
213	return drm_gem_shmem_get_sg_table(shmem);
214}
215
216/*
217 * drm_gem_shmem_object_vmap - GEM object function for drm_gem_shmem_vmap()
218 * @obj: GEM object
219 * @map: Returns the kernel virtual address of the SHMEM GEM object's backing store.
220 *
221 * This function wraps drm_gem_shmem_vmap(). Drivers that employ the shmem helpers should
222 * use it as their &drm_gem_object_funcs.vmap handler.
223 *
224 * Returns:
225 * 0 on success or a negative error code on failure.
226 */
227static inline int drm_gem_shmem_object_vmap(struct drm_gem_object *obj,
228					    struct iosys_map *map)
229{
230	struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
231
232	return drm_gem_shmem_vmap(shmem, map);
233}
234
235/*
236 * drm_gem_shmem_object_vunmap - GEM object function for drm_gem_shmem_vunmap()
237 * @obj: GEM object
238 * @map: Kernel virtual address where the SHMEM GEM object was mapped
239 *
240 * This function wraps drm_gem_shmem_vunmap(). Drivers that employ the shmem helpers should
241 * use it as their &drm_gem_object_funcs.vunmap handler.
242 */
243static inline void drm_gem_shmem_object_vunmap(struct drm_gem_object *obj,
244					       struct iosys_map *map)
245{
246	struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
247
248	drm_gem_shmem_vunmap(shmem, map);
249}
250
251/**
252 * drm_gem_shmem_object_mmap - GEM object function for drm_gem_shmem_mmap()
253 * @obj: GEM object
254 * @vma: VMA for the area to be mapped
255 *
256 * This function wraps drm_gem_shmem_mmap(). Drivers that employ the shmem helpers should
257 * use it as their &drm_gem_object_funcs.mmap handler.
258 *
259 * Returns:
260 * 0 on success or a negative error code on failure.
261 */
262static inline int drm_gem_shmem_object_mmap(struct drm_gem_object *obj, struct vm_area_struct *vma)
263{
264	struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
265
266	return drm_gem_shmem_mmap(shmem, vma);
267}
268
269/*
270 * Driver ops
271 */
272
273struct drm_gem_object *
274drm_gem_shmem_prime_import_sg_table(struct drm_device *dev,
275				    struct dma_buf_attachment *attach,
276				    struct sg_table *sgt);
277int drm_gem_shmem_dumb_create(struct drm_file *file, struct drm_device *dev,
278			      struct drm_mode_create_dumb *args);
279
280/**
281 * DRM_GEM_SHMEM_DRIVER_OPS - Default shmem GEM operations
282 *
283 * This macro provides a shortcut for setting the shmem GEM operations in
284 * the &drm_driver structure.
285 */
286#define DRM_GEM_SHMEM_DRIVER_OPS \
287	.gem_prime_import_sg_table = drm_gem_shmem_prime_import_sg_table, \
288	.dumb_create		   = drm_gem_shmem_dumb_create
289
290#endif /* __DRM_GEM_SHMEM_HELPER_H__ */