1 /**************************************************************************
2 *
3 * Copyright (c) 2006-2009 Vmware, Inc., Palo Alto, CA., USA
4 * All Rights Reserved.
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a
7 * copy of this software and associated documentation files (the
8 * "Software"), to deal in the Software without restriction, including
9 * without limitation the rights to use, copy, modify, merge, publish,
10 * distribute, sub license, and/or sell copies of the Software, and to
11 * permit persons to whom the Software is furnished to do so, subject to
12 * the following conditions:
13 *
14 * The above copyright notice and this permission notice (including the
15 * next paragraph) shall be included in all copies or substantial portions
16 * of the Software.
17 *
18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
19 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
20 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
21 * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
22 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
23 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
24 * USE OR OTHER DEALINGS IN THE SOFTWARE.
25 *
26 **************************************************************************/
27 #ifndef _TTM_TT_H_
28 #define _TTM_TT_H_
29
30 #include <linux/pagemap.h>
31 #include <linux/types.h>
32 #include <drm/ttm/ttm_caching.h>
33 #include <drm/ttm/ttm_kmap_iter.h>
34
35 struct ttm_device;
36 struct ttm_tt;
37 struct ttm_resource;
38 struct ttm_buffer_object;
39 struct ttm_operation_ctx;
40
41 /**
42 * struct ttm_tt - This is a structure holding the pages, caching- and aperture
43 * binding status for a buffer object that isn't backed by fixed (VRAM / AGP)
44 * memory.
45 */
46 struct ttm_tt {
47 /** @pages: Array of pages backing the data. */
48 struct page **pages;
49 /**
50 * @page_flags: The page flags.
51 *
52 * Supported values:
53 *
54 * TTM_TT_FLAG_SWAPPED: Set by TTM when the pages have been unpopulated
55 * and swapped out by TTM. Calling ttm_tt_populate() will then swap the
56 * pages back in, and unset the flag. Drivers should in general never
57 * need to touch this.
58 *
59 * TTM_TT_FLAG_ZERO_ALLOC: Set if the pages will be zeroed on
60 * allocation.
61 *
62 * TTM_TT_FLAG_EXTERNAL: Set if the underlying pages were allocated
63 * externally, like with dma-buf or userptr. This effectively disables
64 * TTM swapping out such pages. Also important is to prevent TTM from
65 * ever directly mapping these pages.
66 *
67 * Note that enum ttm_bo_type.ttm_bo_type_sg objects will always enable
68 * this flag.
69 *
70 * TTM_TT_FLAG_EXTERNAL_MAPPABLE: Same behaviour as
71 * TTM_TT_FLAG_EXTERNAL, but with the reduced restriction that it is
72 * still valid to use TTM to map the pages directly. This is useful when
73 * implementing a ttm_tt backend which still allocates driver owned
74 * pages underneath(say with shmem).
75 *
76 * Note that since this also implies TTM_TT_FLAG_EXTERNAL, the usage
77 * here should always be:
78 *
79 * page_flags = TTM_TT_FLAG_EXTERNAL |
80 * TTM_TT_FLAG_EXTERNAL_MAPPABLE;
81 *
82 * TTM_TT_FLAG_PRIV_POPULATED: TTM internal only. DO NOT USE. This is
83 * set by TTM after ttm_tt_populate() has successfully returned, and is
84 * then unset when TTM calls ttm_tt_unpopulate().
85 */
86 #define TTM_TT_FLAG_SWAPPED BIT(0)
87 #define TTM_TT_FLAG_ZERO_ALLOC BIT(1)
88 #define TTM_TT_FLAG_EXTERNAL BIT(2)
89 #define TTM_TT_FLAG_EXTERNAL_MAPPABLE BIT(3)
90
91 #define TTM_TT_FLAG_PRIV_POPULATED BIT(4)
92 uint32_t page_flags;
93 /** @num_pages: Number of pages in the page array. */
94 uint32_t num_pages;
95 /** @sg: for SG objects via dma-buf. */
96 struct sg_table *sg;
97 /** @dma_address: The DMA (bus) addresses of the pages. */
98 dma_addr_t *dma_address;
99 /** @swap_storage: Pointer to shmem struct file for swap storage. */
100 struct file *swap_storage;
101 /**
102 * @caching: The current caching state of the pages, see enum
103 * ttm_caching.
104 */
105 enum ttm_caching caching;
106 };
107
108 /**
109 * struct ttm_kmap_iter_tt - Specialization of a mappig iterator for a tt.
110 * @base: Embedded struct ttm_kmap_iter providing the usage interface
111 * @tt: Cached struct ttm_tt.
112 * @prot: Cached page protection for mapping.
113 */
114 struct ttm_kmap_iter_tt {
115 struct ttm_kmap_iter base;
116 struct ttm_tt *tt;
117 pgprot_t prot;
118 };
119
ttm_tt_is_populated(struct ttm_tt * tt)120 static inline bool ttm_tt_is_populated(struct ttm_tt *tt)
121 {
122 return tt->page_flags & TTM_TT_FLAG_PRIV_POPULATED;
123 }
124
125 /**
126 * ttm_tt_create
127 *
128 * @bo: pointer to a struct ttm_buffer_object
129 * @zero_alloc: true if allocated pages needs to be zeroed
130 *
131 * Make sure we have a TTM structure allocated for the given BO.
132 * No pages are actually allocated.
133 */
134 int ttm_tt_create(struct ttm_buffer_object *bo, bool zero_alloc);
135
136 /**
137 * ttm_tt_init
138 *
139 * @ttm: The struct ttm_tt.
140 * @bo: The buffer object we create the ttm for.
141 * @page_flags: Page flags as identified by TTM_TT_FLAG_XX flags.
142 * @caching: the desired caching state of the pages
143 * @extra_pages: Extra pages needed for the driver.
144 *
145 * Create a struct ttm_tt to back data with system memory pages.
146 * No pages are actually allocated.
147 * Returns:
148 * NULL: Out of memory.
149 */
150 int ttm_tt_init(struct ttm_tt *ttm, struct ttm_buffer_object *bo,
151 uint32_t page_flags, enum ttm_caching caching,
152 unsigned long extra_pages);
153 int ttm_sg_tt_init(struct ttm_tt *ttm_dma, struct ttm_buffer_object *bo,
154 uint32_t page_flags, enum ttm_caching caching);
155
156 /**
157 * ttm_tt_fini
158 *
159 * @ttm: the ttm_tt structure.
160 *
161 * Free memory of ttm_tt structure
162 */
163 void ttm_tt_fini(struct ttm_tt *ttm);
164
165 /**
166 * ttm_tt_destroy:
167 *
168 * @bdev: the ttm_device this object belongs to
169 * @ttm: The struct ttm_tt.
170 *
171 * Unbind, unpopulate and destroy common struct ttm_tt.
172 */
173 void ttm_tt_destroy(struct ttm_device *bdev, struct ttm_tt *ttm);
174
175 /**
176 * ttm_tt_swapin:
177 *
178 * @ttm: The struct ttm_tt.
179 *
180 * Swap in a previously swap out ttm_tt.
181 */
182 int ttm_tt_swapin(struct ttm_tt *ttm);
183 int ttm_tt_swapout(struct ttm_device *bdev, struct ttm_tt *ttm,
184 gfp_t gfp_flags);
185
186 /**
187 * ttm_tt_populate - allocate pages for a ttm
188 *
189 * @bdev: the ttm_device this object belongs to
190 * @ttm: Pointer to the ttm_tt structure
191 * @ctx: operation context for populating the tt object.
192 *
193 * Calls the driver method to allocate pages for a ttm
194 */
195 int ttm_tt_populate(struct ttm_device *bdev, struct ttm_tt *ttm,
196 struct ttm_operation_ctx *ctx);
197
198 /**
199 * ttm_tt_unpopulate - free pages from a ttm
200 *
201 * @bdev: the ttm_device this object belongs to
202 * @ttm: Pointer to the ttm_tt structure
203 *
204 * Calls the driver method to free all pages from a ttm
205 */
206 void ttm_tt_unpopulate(struct ttm_device *bdev, struct ttm_tt *ttm);
207
208 /**
209 * ttm_tt_mark_for_clear - Mark pages for clearing on populate.
210 *
211 * @ttm: Pointer to the ttm_tt structure
212 *
213 * Marks pages for clearing so that the next time the page vector is
214 * populated, the pages will be cleared.
215 */
ttm_tt_mark_for_clear(struct ttm_tt * ttm)216 static inline void ttm_tt_mark_for_clear(struct ttm_tt *ttm)
217 {
218 ttm->page_flags |= TTM_TT_FLAG_ZERO_ALLOC;
219 }
220
221 void ttm_tt_mgr_init(unsigned long num_pages, unsigned long num_dma32_pages);
222
223 struct ttm_kmap_iter *ttm_kmap_iter_tt_init(struct ttm_kmap_iter_tt *iter_tt,
224 struct ttm_tt *tt);
225 unsigned long ttm_tt_pages_limit(void);
226 #if IS_ENABLED(CONFIG_AGP)
227 #include <linux/agp_backend.h>
228
229 /**
230 * ttm_agp_tt_create
231 *
232 * @bo: Buffer object we allocate the ttm for.
233 * @bridge: The agp bridge this device is sitting on.
234 * @page_flags: Page flags as identified by TTM_TT_FLAG_XX flags.
235 *
236 *
237 * Create a TTM backend that uses the indicated AGP bridge as an aperture
238 * for TT memory. This function uses the linux agpgart interface to
239 * bind and unbind memory backing a ttm_tt.
240 */
241 struct ttm_tt *ttm_agp_tt_create(struct ttm_buffer_object *bo,
242 struct agp_bridge_data *bridge,
243 uint32_t page_flags);
244 int ttm_agp_bind(struct ttm_tt *ttm, struct ttm_resource *bo_mem);
245 void ttm_agp_unbind(struct ttm_tt *ttm);
246 void ttm_agp_destroy(struct ttm_tt *ttm);
247 bool ttm_agp_is_bound(struct ttm_tt *ttm);
248 #endif
249
250 #endif
251
