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_cached: map object cached (instead of using writecombine).
102	 */
103	bool map_cached;
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_object(struct drm_gem_object *obj);
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_object *obj);
115void drm_gem_shmem_unpin(struct drm_gem_object *obj);
116void *drm_gem_shmem_vmap(struct drm_gem_object *obj);
117void drm_gem_shmem_vunmap(struct drm_gem_object *obj, void *vaddr);
118
119int drm_gem_shmem_madvise(struct drm_gem_object *obj, int madv);
120
121static inline bool drm_gem_shmem_is_purgeable(struct drm_gem_shmem_object *shmem)
122{
123	return (shmem->madv > 0) &&
124		!shmem->vmap_use_count && shmem->sgt &&
125		!shmem->base.dma_buf && !shmem->base.import_attach;
126}
127
128void drm_gem_shmem_purge_locked(struct drm_gem_object *obj);
129bool drm_gem_shmem_purge(struct drm_gem_object *obj);
130
131struct drm_gem_shmem_object *
132drm_gem_shmem_create_with_handle(struct drm_file *file_priv,
133				 struct drm_device *dev, size_t size,
134				 uint32_t *handle);
135
136struct drm_gem_object *
137drm_gem_shmem_create_object_cached(struct drm_device *dev, size_t size);
138
139int drm_gem_shmem_dumb_create(struct drm_file *file, struct drm_device *dev,
140			      struct drm_mode_create_dumb *args);
141
142int drm_gem_shmem_mmap(struct drm_gem_object *obj, struct vm_area_struct *vma);
143
144void drm_gem_shmem_print_info(struct drm_printer *p, unsigned int indent,
145			      const struct drm_gem_object *obj);
146
147struct sg_table *drm_gem_shmem_get_sg_table(struct drm_gem_object *obj);
148struct drm_gem_object *
149drm_gem_shmem_prime_import_sg_table(struct drm_device *dev,
150				    struct dma_buf_attachment *attach,
151				    struct sg_table *sgt);
152
153struct sg_table *drm_gem_shmem_get_pages_sgt(struct drm_gem_object *obj);
154
155/**
156 * DRM_GEM_SHMEM_DRIVER_OPS - Default shmem GEM operations
157 *
158 * This macro provides a shortcut for setting the shmem GEM operations in
159 * the &drm_driver structure.
160 */
161#define DRM_GEM_SHMEM_DRIVER_OPS \
162	.prime_handle_to_fd	= drm_gem_prime_handle_to_fd, \
163	.prime_fd_to_handle	= drm_gem_prime_fd_to_handle, \
164	.gem_prime_import_sg_table = drm_gem_shmem_prime_import_sg_table, \
165	.gem_prime_mmap		= drm_gem_prime_mmap, \
166	.dumb_create		= drm_gem_shmem_dumb_create
167
168#endif /* __DRM_GEM_SHMEM_HELPER_H__ */
169