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
15 struct dma_buf_attachment;
16 struct drm_mode_create_dumb;
17 struct drm_printer;
18 struct sg_table;
19
20 /**
21 * struct drm_gem_shmem_object - GEM object backed by shmem
22 */
23 struct 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 #define to_drm_gem_shmem_obj(obj) \
102 container_of(obj, struct drm_gem_shmem_object, base)
103
104 /**
105 * DEFINE_DRM_GEM_SHMEM_FOPS() - Macro to generate file operations for shmem drivers
106 * @name: name for the generated structure
107 *
108 * This macro autogenerates a suitable &struct file_operations for shmem based
109 * drivers, which can be assigned to &drm_driver.fops. Note that this structure
110 * cannot be shared between drivers, because it contains a reference to the
111 * current module using THIS_MODULE.
112 *
113 * Note that the declaration is already marked as static - if you need a
114 * non-static version of this you're probably doing it wrong and will break the
115 * THIS_MODULE reference by accident.
116 */
117 #define DEFINE_DRM_GEM_SHMEM_FOPS(name) \
118 static const struct file_operations name = {\
119 .owner = THIS_MODULE,\
120 .open = drm_open,\
121 .release = drm_release,\
122 .unlocked_ioctl = drm_ioctl,\
123 .compat_ioctl = drm_compat_ioctl,\
124 .poll = drm_poll,\
125 .read = drm_read,\
126 .llseek = noop_llseek,\
127 .mmap = drm_gem_shmem_mmap, \
128 }
129
130 struct drm_gem_shmem_object *drm_gem_shmem_create(struct drm_device *dev, size_t size);
131 void drm_gem_shmem_free_object(struct drm_gem_object *obj);
132
133 int drm_gem_shmem_get_pages(struct drm_gem_shmem_object *shmem);
134 void drm_gem_shmem_put_pages(struct drm_gem_shmem_object *shmem);
135 int drm_gem_shmem_pin(struct drm_gem_object *obj);
136 void drm_gem_shmem_unpin(struct drm_gem_object *obj);
137 void *drm_gem_shmem_vmap(struct drm_gem_object *obj);
138 void drm_gem_shmem_vunmap(struct drm_gem_object *obj, void *vaddr);
139
140 int drm_gem_shmem_madvise(struct drm_gem_object *obj, int madv);
141
drm_gem_shmem_is_purgeable(struct drm_gem_shmem_object * shmem)142 static inline bool drm_gem_shmem_is_purgeable(struct drm_gem_shmem_object *shmem)
143 {
144 return (shmem->madv > 0) &&
145 !shmem->vmap_use_count && shmem->sgt &&
146 !shmem->base.dma_buf && !shmem->base.import_attach;
147 }
148
149 void drm_gem_shmem_purge_locked(struct drm_gem_object *obj);
150 bool drm_gem_shmem_purge(struct drm_gem_object *obj);
151
152 struct drm_gem_shmem_object *
153 drm_gem_shmem_create_with_handle(struct drm_file *file_priv,
154 struct drm_device *dev, size_t size,
155 uint32_t *handle);
156 int drm_gem_shmem_dumb_create(struct drm_file *file, struct drm_device *dev,
157 struct drm_mode_create_dumb *args);
158
159 int drm_gem_shmem_mmap(struct file *filp, struct vm_area_struct *vma);
160
161 extern const struct vm_operations_struct drm_gem_shmem_vm_ops;
162
163 void drm_gem_shmem_print_info(struct drm_printer *p, unsigned int indent,
164 const struct drm_gem_object *obj);
165
166 struct sg_table *drm_gem_shmem_get_sg_table(struct drm_gem_object *obj);
167 struct drm_gem_object *
168 drm_gem_shmem_prime_import_sg_table(struct drm_device *dev,
169 struct dma_buf_attachment *attach,
170 struct sg_table *sgt);
171
172 struct sg_table *drm_gem_shmem_get_pages_sgt(struct drm_gem_object *obj);
173
174 /**
175 * DRM_GEM_SHMEM_DRIVER_OPS - Default shmem GEM operations
176 *
177 * This macro provides a shortcut for setting the shmem GEM operations in
178 * the &drm_driver structure.
179 */
180 #define DRM_GEM_SHMEM_DRIVER_OPS \
181 .prime_handle_to_fd = drm_gem_prime_handle_to_fd, \
182 .prime_fd_to_handle = drm_gem_prime_fd_to_handle, \
183 .gem_prime_import_sg_table = drm_gem_shmem_prime_import_sg_table, \
184 .gem_prime_mmap = drm_gem_prime_mmap, \
185 .dumb_create = drm_gem_shmem_dumb_create
186
187 #endif /* __DRM_GEM_SHMEM_HELPER_H__ */
188