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 vm_page **pages;
49 /** @orders: Array of order values. */
50 unsigned long *orders;
51 /**
52 * @page_flags: The page flags.
53 *
54 * Supported values:
55 *
56 * TTM_TT_FLAG_SWAPPED: Set by TTM when the pages have been unpopulated
57 * and swapped out by TTM. Calling ttm_tt_populate() will then swap the
58 * pages back in, and unset the flag. Drivers should in general never
59 * need to touch this.
60 *
61 * TTM_TT_FLAG_ZERO_ALLOC: Set if the pages will be zeroed on
62 * allocation.
63 *
64 * TTM_TT_FLAG_EXTERNAL: Set if the underlying pages were allocated
65 * externally, like with dma-buf or userptr. This effectively disables
66 * TTM swapping out such pages. Also important is to prevent TTM from
67 * ever directly mapping these pages.
68 *
69 * Note that enum ttm_bo_type.ttm_bo_type_sg objects will always enable
70 * this flag.
71 *
72 * TTM_TT_FLAG_EXTERNAL_MAPPABLE: Same behaviour as
73 * TTM_TT_FLAG_EXTERNAL, but with the reduced restriction that it is
74 * still valid to use TTM to map the pages directly. This is useful when
75 * implementing a ttm_tt backend which still allocates driver owned
76 * pages underneath(say with shmem).
77 *
78 * Note that since this also implies TTM_TT_FLAG_EXTERNAL, the usage
79 * here should always be:
80 *
81 * page_flags = TTM_TT_FLAG_EXTERNAL |
82 * TTM_TT_FLAG_EXTERNAL_MAPPABLE;
83 *
84 * TTM_TT_FLAG_DECRYPTED: The mapped ttm pages should be marked as
85 * not encrypted. The framework will try to match what the dma layer
86 * is doing, but note that it is a little fragile because ttm page
87 * fault handling abuses the DMA api a bit and dma_map_attrs can't be
88 * used to assure pgprot always matches.
89 *
90 * TTM_TT_FLAG_PRIV_POPULATED: TTM internal only. DO NOT USE. This is
91 * set by TTM after ttm_tt_populate() has successfully returned, and is
92 * then unset when TTM calls ttm_tt_unpopulate().
93 */
94 #define TTM_TT_FLAG_SWAPPED BIT(0)
95 #define TTM_TT_FLAG_ZERO_ALLOC BIT(1)
96 #define TTM_TT_FLAG_EXTERNAL BIT(2)
97 #define TTM_TT_FLAG_EXTERNAL_MAPPABLE BIT(3)
98 #define TTM_TT_FLAG_DECRYPTED BIT(4)
99
100 #define TTM_TT_FLAG_PRIV_POPULATED BIT(5)
101 uint32_t page_flags;
102 /** @num_pages: Number of pages in the page array. */
103 uint32_t num_pages;
104 /** @sg: for SG objects via dma-buf. */
105 struct sg_table *sg;
106 /** @dma_address: The DMA (bus) addresses of the pages. */
107 dma_addr_t *dma_address;
108 /** @swap_storage: Pointer to shmem struct file for swap storage. */
109 struct uvm_object *swap_storage;
110 /**
111 * @caching: The current caching state of the pages, see enum
112 * ttm_caching.
113 */
114 enum ttm_caching caching;
115
116 bus_dma_tag_t dmat;
117 bus_dmamap_t map;
118 bus_dma_segment_t *segs;
119 };
120
121 /**
122 * struct ttm_kmap_iter_tt - Specialization of a mappig iterator for a tt.
123 * @base: Embedded struct ttm_kmap_iter providing the usage interface
124 * @tt: Cached struct ttm_tt.
125 * @prot: Cached page protection for mapping.
126 */
127 struct ttm_kmap_iter_tt {
128 struct ttm_kmap_iter base;
129 struct ttm_tt *tt;
130 pgprot_t prot;
131 };
132
ttm_tt_is_populated(struct ttm_tt * tt)133 static inline bool ttm_tt_is_populated(struct ttm_tt *tt)
134 {
135 return tt->page_flags & TTM_TT_FLAG_PRIV_POPULATED;
136 }
137
138 /**
139 * ttm_tt_create
140 *
141 * @bo: pointer to a struct ttm_buffer_object
142 * @zero_alloc: true if allocated pages needs to be zeroed
143 *
144 * Make sure we have a TTM structure allocated for the given BO.
145 * No pages are actually allocated.
146 */
147 int ttm_tt_create(struct ttm_buffer_object *bo, bool zero_alloc);
148
149 /**
150 * ttm_tt_init
151 *
152 * @ttm: The struct ttm_tt.
153 * @bo: The buffer object we create the ttm for.
154 * @page_flags: Page flags as identified by TTM_TT_FLAG_XX flags.
155 * @caching: the desired caching state of the pages
156 * @extra_pages: Extra pages needed for the driver.
157 *
158 * Create a struct ttm_tt to back data with system memory pages.
159 * No pages are actually allocated.
160 * Returns:
161 * NULL: Out of memory.
162 */
163 int ttm_tt_init(struct ttm_tt *ttm, struct ttm_buffer_object *bo,
164 uint32_t page_flags, enum ttm_caching caching,
165 unsigned long extra_pages);
166 int ttm_sg_tt_init(struct ttm_tt *ttm_dma, struct ttm_buffer_object *bo,
167 uint32_t page_flags, enum ttm_caching caching);
168
169 /**
170 * ttm_tt_fini
171 *
172 * @ttm: the ttm_tt structure.
173 *
174 * Free memory of ttm_tt structure
175 */
176 void ttm_tt_fini(struct ttm_tt *ttm);
177
178 /**
179 * ttm_tt_destroy:
180 *
181 * @bdev: the ttm_device this object belongs to
182 * @ttm: The struct ttm_tt.
183 *
184 * Unbind, unpopulate and destroy common struct ttm_tt.
185 */
186 void ttm_tt_destroy(struct ttm_device *bdev, struct ttm_tt *ttm);
187
188 /**
189 * ttm_tt_swapin:
190 *
191 * @ttm: The struct ttm_tt.
192 *
193 * Swap in a previously swap out ttm_tt.
194 */
195 int ttm_tt_swapin(struct ttm_tt *ttm);
196 int ttm_tt_swapout(struct ttm_device *bdev, struct ttm_tt *ttm,
197 gfp_t gfp_flags);
198
199 /**
200 * ttm_tt_populate - allocate pages for a ttm
201 *
202 * @bdev: the ttm_device this object belongs to
203 * @ttm: Pointer to the ttm_tt structure
204 * @ctx: operation context for populating the tt object.
205 *
206 * Calls the driver method to allocate pages for a ttm
207 */
208 int ttm_tt_populate(struct ttm_device *bdev, struct ttm_tt *ttm,
209 struct ttm_operation_ctx *ctx);
210
211 /**
212 * ttm_tt_unpopulate - free pages from a ttm
213 *
214 * @bdev: the ttm_device this object belongs to
215 * @ttm: Pointer to the ttm_tt structure
216 *
217 * Calls the driver method to free all pages from a ttm
218 */
219 void ttm_tt_unpopulate(struct ttm_device *bdev, struct ttm_tt *ttm);
220
221 /**
222 * ttm_tt_mark_for_clear - Mark pages for clearing on populate.
223 *
224 * @ttm: Pointer to the ttm_tt structure
225 *
226 * Marks pages for clearing so that the next time the page vector is
227 * populated, the pages will be cleared.
228 */
ttm_tt_mark_for_clear(struct ttm_tt * ttm)229 static inline void ttm_tt_mark_for_clear(struct ttm_tt *ttm)
230 {
231 ttm->page_flags |= TTM_TT_FLAG_ZERO_ALLOC;
232 }
233
234 void ttm_tt_mgr_init(unsigned long num_pages, unsigned long num_dma32_pages);
235
236 struct ttm_kmap_iter *ttm_kmap_iter_tt_init(struct ttm_kmap_iter_tt *iter_tt,
237 struct ttm_tt *tt);
238 unsigned long ttm_tt_pages_limit(void);
239 #if IS_ENABLED(CONFIG_AGP)
240 #include <linux/agp_backend.h>
241
242 /**
243 * ttm_agp_tt_create
244 *
245 * @bo: Buffer object we allocate the ttm for.
246 * @bridge: The agp bridge this device is sitting on.
247 * @page_flags: Page flags as identified by TTM_TT_FLAG_XX flags.
248 *
249 *
250 * Create a TTM backend that uses the indicated AGP bridge as an aperture
251 * for TT memory. This function uses the linux agpgart interface to
252 * bind and unbind memory backing a ttm_tt.
253 */
254 struct ttm_tt *ttm_agp_tt_create(struct ttm_buffer_object *bo,
255 struct agp_bridge_data *bridge,
256 uint32_t page_flags);
257 int ttm_agp_bind(struct ttm_tt *ttm, struct ttm_resource *bo_mem);
258 void ttm_agp_unbind(struct ttm_tt *ttm);
259 void ttm_agp_destroy(struct ttm_tt *ttm);
260 bool ttm_agp_is_bound(struct ttm_tt *ttm);
261 #endif
262
263 #endif
264