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
35struct ttm_backup;
36struct ttm_device;
37struct ttm_tt;
38struct ttm_resource;
39struct ttm_buffer_object;
40struct ttm_operation_ctx;
41struct ttm_pool_tt_restore;
42
43/**
44 * struct ttm_tt - This is a structure holding the pages, caching- and aperture
45 * binding status for a buffer object that isn't backed by fixed (VRAM / AGP)
46 * memory.
47 */
48struct ttm_tt {
49 /** @pages: Array of pages backing the data. */
50 struct page **pages;
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_BACKED_UP: TTM internal only. This is set if the
91 * struct ttm_tt has been (possibly partially) backed up.
92 *
93 * TTM_TT_FLAG_PRIV_POPULATED: TTM internal only. DO NOT USE. This is
94 * set by TTM after ttm_tt_populate() has successfully returned, and is
95 * then unset when TTM calls ttm_tt_unpopulate().
96 *
97 */
98#define TTM_TT_FLAG_SWAPPED BIT(0)
99#define TTM_TT_FLAG_ZERO_ALLOC BIT(1)
100#define TTM_TT_FLAG_EXTERNAL BIT(2)
101#define TTM_TT_FLAG_EXTERNAL_MAPPABLE BIT(3)
102#define TTM_TT_FLAG_DECRYPTED BIT(4)
103#define TTM_TT_FLAG_BACKED_UP BIT(5)
104
105#define TTM_TT_FLAG_PRIV_POPULATED BIT(6)
106 uint32_t page_flags;
107 /** @num_pages: Number of pages in the page array. */
108 uint32_t num_pages;
109 /** @sg: for SG objects via dma-buf. */
110 struct sg_table *sg;
111 /** @dma_address: The DMA (bus) addresses of the pages. */
112 dma_addr_t *dma_address;
113 /** @swap_storage: Pointer to shmem struct file for swap storage. */
114 struct file *swap_storage;
115 /**
116 * @backup: Pointer to backup struct for backed up tts.
117 * Could be unified with @swap_storage. Meanwhile, the driver's
118 * ttm_tt_create() callback is responsible for assigning
119 * this field.
120 */
121 struct file *backup;
122 /**
123 * @caching: The current caching state of the pages, see enum
124 * ttm_caching.
125 */
126 enum ttm_caching caching;
127 /** @restore: Partial restoration from backup state. TTM private */
128 struct ttm_pool_tt_restore *restore;
129};
130
131/**
132 * struct ttm_kmap_iter_tt - Specialization of a mappig iterator for a tt.
133 * @base: Embedded struct ttm_kmap_iter providing the usage interface
134 * @tt: Cached struct ttm_tt.
135 * @prot: Cached page protection for mapping.
136 */
137struct ttm_kmap_iter_tt {
138 struct ttm_kmap_iter base;
139 struct ttm_tt *tt;
140 pgprot_t prot;
141};
142
143static inline bool ttm_tt_is_populated(struct ttm_tt *tt)
144{
145 return tt->page_flags & TTM_TT_FLAG_PRIV_POPULATED;
146}
147
148/**
149 * ttm_tt_is_swapped() - Whether the ttm_tt is swapped out or backed up
150 * @tt: The struct ttm_tt.
151 *
152 * Return: true if swapped or backed up, false otherwise.
153 */
154static inline bool ttm_tt_is_swapped(const struct ttm_tt *tt)
155{
156 return tt->page_flags & (TTM_TT_FLAG_SWAPPED | TTM_TT_FLAG_BACKED_UP);
157}
158
159/**
160 * ttm_tt_is_backed_up() - Whether the ttm_tt backed up
161 * @tt: The struct ttm_tt.
162 *
163 * Return: true if swapped or backed up, false otherwise.
164 */
165static inline bool ttm_tt_is_backed_up(const struct ttm_tt *tt)
166{
167 return tt->page_flags & TTM_TT_FLAG_BACKED_UP;
168}
169
170/**
171 * ttm_tt_clear_backed_up() - Clear the ttm_tt backed-up status
172 * @tt: The struct ttm_tt.
173 *
174 * Drivers can use this functionto clear the backed-up status,
175 * for example before destroying or re-validating a purged tt.
176 */
177static inline void ttm_tt_clear_backed_up(struct ttm_tt *tt)
178{
179 tt->page_flags &= ~TTM_TT_FLAG_BACKED_UP;
180}
181
182/**
183 * ttm_tt_create
184 *
185 * @bo: pointer to a struct ttm_buffer_object
186 * @zero_alloc: true if allocated pages needs to be zeroed
187 *
188 * Make sure we have a TTM structure allocated for the given BO.
189 * No pages are actually allocated.
190 */
191int ttm_tt_create(struct ttm_buffer_object *bo, bool zero_alloc);
192
193/**
194 * ttm_tt_init
195 *
196 * @ttm: The struct ttm_tt.
197 * @bo: The buffer object we create the ttm for.
198 * @page_flags: Page flags as identified by TTM_TT_FLAG_XX flags.
199 * @caching: the desired caching state of the pages
200 * @extra_pages: Extra pages needed for the driver.
201 *
202 * Create a struct ttm_tt to back data with system memory pages.
203 * No pages are actually allocated.
204 * Returns:
205 * NULL: Out of memory.
206 */
207int ttm_tt_init(struct ttm_tt *ttm, struct ttm_buffer_object *bo,
208 uint32_t page_flags, enum ttm_caching caching,
209 unsigned long extra_pages);
210int ttm_sg_tt_init(struct ttm_tt *ttm_dma, struct ttm_buffer_object *bo,
211 uint32_t page_flags, enum ttm_caching caching);
212
213/**
214 * ttm_tt_fini
215 *
216 * @ttm: the ttm_tt structure.
217 *
218 * Free memory of ttm_tt structure
219 */
220void ttm_tt_fini(struct ttm_tt *ttm);
221
222/**
223 * ttm_tt_destroy:
224 *
225 * @bdev: the ttm_device this object belongs to
226 * @ttm: The struct ttm_tt.
227 *
228 * Unbind, unpopulate and destroy common struct ttm_tt.
229 */
230void ttm_tt_destroy(struct ttm_device *bdev, struct ttm_tt *ttm);
231
232/**
233 * ttm_tt_swapin:
234 *
235 * @ttm: The struct ttm_tt.
236 *
237 * Swap in a previously swap out ttm_tt.
238 */
239int ttm_tt_swapin(struct ttm_tt *ttm);
240int ttm_tt_swapout(struct ttm_device *bdev, struct ttm_tt *ttm,
241 gfp_t gfp_flags);
242
243/**
244 * ttm_tt_populate - allocate pages for a ttm
245 *
246 * @bdev: the ttm_device this object belongs to
247 * @ttm: Pointer to the ttm_tt structure
248 * @ctx: operation context for populating the tt object.
249 *
250 * Calls the driver method to allocate pages for a ttm
251 */
252int ttm_tt_populate(struct ttm_device *bdev, struct ttm_tt *ttm,
253 struct ttm_operation_ctx *ctx);
254
255/**
256 * ttm_tt_unpopulate - free pages from a ttm
257 *
258 * @bdev: the ttm_device this object belongs to
259 * @ttm: Pointer to the ttm_tt structure
260 *
261 * Calls the driver method to free all pages from a ttm
262 */
263void ttm_tt_unpopulate(struct ttm_device *bdev, struct ttm_tt *ttm);
264
265/**
266 * ttm_tt_mark_for_clear - Mark pages for clearing on populate.
267 *
268 * @ttm: Pointer to the ttm_tt structure
269 *
270 * Marks pages for clearing so that the next time the page vector is
271 * populated, the pages will be cleared.
272 */
273static inline void ttm_tt_mark_for_clear(struct ttm_tt *ttm)
274{
275 ttm->page_flags |= TTM_TT_FLAG_ZERO_ALLOC;
276}
277
278void ttm_tt_mgr_init(unsigned long num_pages, unsigned long num_dma32_pages);
279
280struct ttm_kmap_iter *ttm_kmap_iter_tt_init(struct ttm_kmap_iter_tt *iter_tt,
281 struct ttm_tt *tt);
282unsigned long ttm_tt_pages_limit(void);
283
284/**
285 * struct ttm_backup_flags - Flags to govern backup behaviour.
286 * @purge: Free pages without backing up. Bypass pools.
287 * @writeback: Attempt to copy contents directly to swap space, even
288 * if that means blocking on writes to external memory.
289 */
290struct ttm_backup_flags {
291 u32 purge : 1;
292 u32 writeback : 1;
293};
294
295long ttm_tt_backup(struct ttm_device *bdev, struct ttm_tt *tt,
296 const struct ttm_backup_flags flags);
297
298int ttm_tt_restore(struct ttm_device *bdev, struct ttm_tt *tt,
299 const struct ttm_operation_ctx *ctx);
300
301int ttm_tt_setup_backup(struct ttm_tt *tt);
302
303#if IS_ENABLED(CONFIG_AGP)
304#include <linux/agp_backend.h>
305
306/**
307 * ttm_agp_tt_create
308 *
309 * @bo: Buffer object we allocate the ttm for.
310 * @bridge: The agp bridge this device is sitting on.
311 * @page_flags: Page flags as identified by TTM_TT_FLAG_XX flags.
312 *
313 *
314 * Create a TTM backend that uses the indicated AGP bridge as an aperture
315 * for TT memory. This function uses the linux agpgart interface to
316 * bind and unbind memory backing a ttm_tt.
317 */
318struct ttm_tt *ttm_agp_tt_create(struct ttm_buffer_object *bo,
319 struct agp_bridge_data *bridge,
320 uint32_t page_flags);
321int ttm_agp_bind(struct ttm_tt *ttm, struct ttm_resource *bo_mem);
322void ttm_agp_unbind(struct ttm_tt *ttm);
323void ttm_agp_destroy(struct ttm_tt *ttm);
324bool ttm_agp_is_bound(struct ttm_tt *ttm);
325#endif
326
327#endif
328