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v4.6
 
  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/*
 28 * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>
 29 */
 30
 31#define pr_fmt(fmt) "[TTM] " fmt
 32
 33#include <linux/sched.h>
 34#include <linux/highmem.h>
 35#include <linux/pagemap.h>
 36#include <linux/shmem_fs.h>
 37#include <linux/file.h>
 38#include <linux/swap.h>
 39#include <linux/slab.h>
 40#include <linux/export.h>
 41#include <drm/drm_cache.h>
 42#include <drm/drm_mem_util.h>
 43#include <drm/ttm/ttm_module.h>
 44#include <drm/ttm/ttm_bo_driver.h>
 45#include <drm/ttm/ttm_placement.h>
 46#include <drm/ttm/ttm_page_alloc.h>
 47
 48/**
 49 * Allocates storage for pointers to the pages that back the ttm.
 50 */
 51static void ttm_tt_alloc_page_directory(struct ttm_tt *ttm)
 52{
 53	ttm->pages = drm_calloc_large(ttm->num_pages, sizeof(void*));
 54}
 55
 56static void ttm_dma_tt_alloc_page_directory(struct ttm_dma_tt *ttm)
 57{
 58	ttm->ttm.pages = drm_calloc_large(ttm->ttm.num_pages,
 59					  sizeof(*ttm->ttm.pages) +
 60					  sizeof(*ttm->dma_address) +
 61					  sizeof(*ttm->cpu_address));
 62	ttm->cpu_address = (void *) (ttm->ttm.pages + ttm->ttm.num_pages);
 63	ttm->dma_address = (void *) (ttm->cpu_address + ttm->ttm.num_pages);
 64}
 65
 66#ifdef CONFIG_X86
 67static inline int ttm_tt_set_page_caching(struct page *p,
 68					  enum ttm_caching_state c_old,
 69					  enum ttm_caching_state c_new)
 70{
 71	int ret = 0;
 72
 73	if (PageHighMem(p))
 74		return 0;
 75
 76	if (c_old != tt_cached) {
 77		/* p isn't in the default caching state, set it to
 78		 * writeback first to free its current memtype. */
 79
 80		ret = set_pages_wb(p, 1);
 81		if (ret)
 82			return ret;
 83	}
 84
 85	if (c_new == tt_wc)
 86		ret = set_memory_wc((unsigned long) page_address(p), 1);
 87	else if (c_new == tt_uncached)
 88		ret = set_pages_uc(p, 1);
 89
 90	return ret;
 91}
 92#else /* CONFIG_X86 */
 93static inline int ttm_tt_set_page_caching(struct page *p,
 94					  enum ttm_caching_state c_old,
 95					  enum ttm_caching_state c_new)
 96{
 97	return 0;
 98}
 99#endif /* CONFIG_X86 */
100
101/*
102 * Change caching policy for the linear kernel map
103 * for range of pages in a ttm.
104 */
105
106static int ttm_tt_set_caching(struct ttm_tt *ttm,
107			      enum ttm_caching_state c_state)
108{
109	int i, j;
110	struct page *cur_page;
111	int ret;
112
113	if (ttm->caching_state == c_state)
114		return 0;
115
116	if (ttm->state == tt_unpopulated) {
117		/* Change caching but don't populate */
118		ttm->caching_state = c_state;
119		return 0;
120	}
121
122	if (ttm->caching_state == tt_cached)
123		drm_clflush_pages(ttm->pages, ttm->num_pages);
124
125	for (i = 0; i < ttm->num_pages; ++i) {
126		cur_page = ttm->pages[i];
127		if (likely(cur_page != NULL)) {
128			ret = ttm_tt_set_page_caching(cur_page,
129						      ttm->caching_state,
130						      c_state);
131			if (unlikely(ret != 0))
132				goto out_err;
133		}
 
 
 
 
134	}
135
136	ttm->caching_state = c_state;
 
 
137
138	return 0;
139
140out_err:
141	for (j = 0; j < i; ++j) {
142		cur_page = ttm->pages[j];
143		if (likely(cur_page != NULL)) {
144			(void)ttm_tt_set_page_caching(cur_page, c_state,
145						      ttm->caching_state);
146		}
147	}
148
149	return ret;
150}
151
152int ttm_tt_set_placement_caching(struct ttm_tt *ttm, uint32_t placement)
 
 
 
153{
154	enum ttm_caching_state state;
 
 
 
 
 
155
156	if (placement & TTM_PL_FLAG_WC)
157		state = tt_wc;
158	else if (placement & TTM_PL_FLAG_UNCACHED)
159		state = tt_uncached;
160	else
161		state = tt_cached;
 
 
162
163	return ttm_tt_set_caching(ttm, state);
 
164}
165EXPORT_SYMBOL(ttm_tt_set_placement_caching);
166
167void ttm_tt_destroy(struct ttm_tt *ttm)
168{
169	if (unlikely(ttm == NULL))
170		return;
171
172	if (ttm->state == tt_bound) {
173		ttm_tt_unbind(ttm);
174	}
 
175
176	if (ttm->state == tt_unbound)
177		ttm_tt_unpopulate(ttm);
 
178
179	if (!(ttm->page_flags & TTM_PAGE_FLAG_PERSISTENT_SWAP) &&
180	    ttm->swap_storage)
181		fput(ttm->swap_storage);
182
183	ttm->swap_storage = NULL;
184	ttm->func->destroy(ttm);
185}
 
186
187int ttm_tt_init(struct ttm_tt *ttm, struct ttm_bo_device *bdev,
188		unsigned long size, uint32_t page_flags,
189		struct page *dummy_read_page)
190{
191	ttm->bdev = bdev;
192	ttm->glob = bdev->glob;
193	ttm->num_pages = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
194	ttm->caching_state = tt_cached;
195	ttm->page_flags = page_flags;
196	ttm->dummy_read_page = dummy_read_page;
197	ttm->state = tt_unpopulated;
198	ttm->swap_storage = NULL;
199
200	ttm_tt_alloc_page_directory(ttm);
201	if (!ttm->pages) {
202		ttm_tt_destroy(ttm);
203		pr_err("Failed allocating page table\n");
204		return -ENOMEM;
205	}
206	return 0;
207}
208EXPORT_SYMBOL(ttm_tt_init);
209
210void ttm_tt_fini(struct ttm_tt *ttm)
 
 
 
211{
212	drm_free_large(ttm->pages);
213	ttm->pages = NULL;
214}
215EXPORT_SYMBOL(ttm_tt_fini);
216
217int ttm_dma_tt_init(struct ttm_dma_tt *ttm_dma, struct ttm_bo_device *bdev,
218		unsigned long size, uint32_t page_flags,
219		struct page *dummy_read_page)
220{
221	struct ttm_tt *ttm = &ttm_dma->ttm;
222
223	ttm->bdev = bdev;
224	ttm->glob = bdev->glob;
225	ttm->num_pages = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
226	ttm->caching_state = tt_cached;
227	ttm->page_flags = page_flags;
228	ttm->dummy_read_page = dummy_read_page;
229	ttm->state = tt_unpopulated;
230	ttm->swap_storage = NULL;
 
 
 
 
 
 
 
 
231
232	INIT_LIST_HEAD(&ttm_dma->pages_list);
233	ttm_dma_tt_alloc_page_directory(ttm_dma);
234	if (!ttm->pages) {
235		ttm_tt_destroy(ttm);
236		pr_err("Failed allocating page table\n");
237		return -ENOMEM;
238	}
239	return 0;
240}
241EXPORT_SYMBOL(ttm_dma_tt_init);
242
243void ttm_dma_tt_fini(struct ttm_dma_tt *ttm_dma)
244{
245	struct ttm_tt *ttm = &ttm_dma->ttm;
246
247	drm_free_large(ttm->pages);
 
248	ttm->pages = NULL;
249	ttm_dma->cpu_address = NULL;
250	ttm_dma->dma_address = NULL;
251}
252EXPORT_SYMBOL(ttm_dma_tt_fini);
253
254void ttm_tt_unbind(struct ttm_tt *ttm)
 
255{
256	int ret;
257
258	if (ttm->state == tt_bound) {
259		ret = ttm->func->unbind(ttm);
260		BUG_ON(ret);
261		ttm->state = tt_unbound;
262	}
263}
264
265int ttm_tt_bind(struct ttm_tt *ttm, struct ttm_mem_reg *bo_mem)
266{
267	int ret = 0;
268
269	if (!ttm)
270		return -EINVAL;
271
272	if (ttm->state == tt_bound)
273		return 0;
274
275	ret = ttm->bdev->driver->ttm_tt_populate(ttm);
276	if (ret)
277		return ret;
278
279	ret = ttm->func->bind(ttm, bo_mem);
280	if (unlikely(ret != 0))
281		return ret;
282
283	ttm->state = tt_bound;
284
 
 
 
 
 
 
 
 
285	return 0;
286}
287EXPORT_SYMBOL(ttm_tt_bind);
288
289int ttm_tt_swapin(struct ttm_tt *ttm)
290{
291	struct address_space *swap_space;
292	struct file *swap_storage;
293	struct page *from_page;
294	struct page *to_page;
295	int i;
296	int ret = -ENOMEM;
297
298	swap_storage = ttm->swap_storage;
299	BUG_ON(swap_storage == NULL);
300
301	swap_space = file_inode(swap_storage)->i_mapping;
 
302
303	for (i = 0; i < ttm->num_pages; ++i) {
304		from_page = shmem_read_mapping_page(swap_space, i);
 
305		if (IS_ERR(from_page)) {
306			ret = PTR_ERR(from_page);
307			goto out_err;
308		}
309		to_page = ttm->pages[i];
310		if (unlikely(to_page == NULL))
 
311			goto out_err;
 
312
313		copy_highpage(to_page, from_page);
314		put_page(from_page);
315	}
316
317	if (!(ttm->page_flags & TTM_PAGE_FLAG_PERSISTENT_SWAP))
318		fput(swap_storage);
319	ttm->swap_storage = NULL;
320	ttm->page_flags &= ~TTM_PAGE_FLAG_SWAPPED;
321
322	return 0;
 
323out_err:
324	return ret;
325}
326
327int ttm_tt_swapout(struct ttm_tt *ttm, struct file *persistent_swap_storage)
 
 
 
 
 
 
 
 
 
 
 
328{
 
329	struct address_space *swap_space;
330	struct file *swap_storage;
331	struct page *from_page;
332	struct page *to_page;
333	int i;
334	int ret = -ENOMEM;
335
336	BUG_ON(ttm->state != tt_unbound && ttm->state != tt_unpopulated);
337	BUG_ON(ttm->caching_state != tt_cached);
338
339	if (!persistent_swap_storage) {
340		swap_storage = shmem_file_setup("ttm swap",
341						ttm->num_pages << PAGE_SHIFT,
342						0);
343		if (IS_ERR(swap_storage)) {
344			pr_err("Failed allocating swap storage\n");
345			return PTR_ERR(swap_storage);
346		}
347	} else
348		swap_storage = persistent_swap_storage;
349
350	swap_space = file_inode(swap_storage)->i_mapping;
 
351
352	for (i = 0; i < ttm->num_pages; ++i) {
353		from_page = ttm->pages[i];
354		if (unlikely(from_page == NULL))
355			continue;
356		to_page = shmem_read_mapping_page(swap_space, i);
 
357		if (IS_ERR(to_page)) {
358			ret = PTR_ERR(to_page);
359			goto out_err;
360		}
361		copy_highpage(to_page, from_page);
362		set_page_dirty(to_page);
363		mark_page_accessed(to_page);
364		put_page(to_page);
365	}
366
367	ttm_tt_unpopulate(ttm);
368	ttm->swap_storage = swap_storage;
369	ttm->page_flags |= TTM_PAGE_FLAG_SWAPPED;
370	if (persistent_swap_storage)
371		ttm->page_flags |= TTM_PAGE_FLAG_PERSISTENT_SWAP;
372
373	return 0;
 
374out_err:
375	if (!persistent_swap_storage)
376		fput(swap_storage);
377
378	return ret;
379}
380
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
381static void ttm_tt_clear_mapping(struct ttm_tt *ttm)
382{
383	pgoff_t i;
384	struct page **page = ttm->pages;
385
386	if (ttm->page_flags & TTM_PAGE_FLAG_SG)
387		return;
388
389	for (i = 0; i < ttm->num_pages; ++i) {
390		(*page)->mapping = NULL;
391		(*page++)->index = 0;
392	}
393}
394
395void ttm_tt_unpopulate(struct ttm_tt *ttm)
396{
397	if (ttm->state == tt_unpopulated)
398		return;
399
400	ttm_tt_clear_mapping(ttm);
401	ttm->bdev->driver->ttm_tt_unpopulate(ttm);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
402}
v5.14.15
  1/* SPDX-License-Identifier: GPL-2.0 OR MIT */
  2/**************************************************************************
  3 *
  4 * Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA
  5 * All Rights Reserved.
  6 *
  7 * Permission is hereby granted, free of charge, to any person obtaining a
  8 * copy of this software and associated documentation files (the
  9 * "Software"), to deal in the Software without restriction, including
 10 * without limitation the rights to use, copy, modify, merge, publish,
 11 * distribute, sub license, and/or sell copies of the Software, and to
 12 * permit persons to whom the Software is furnished to do so, subject to
 13 * the following conditions:
 14 *
 15 * The above copyright notice and this permission notice (including the
 16 * next paragraph) shall be included in all copies or substantial portions
 17 * of the Software.
 18 *
 19 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 20 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 21 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
 22 * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
 23 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
 24 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
 25 * USE OR OTHER DEALINGS IN THE SOFTWARE.
 26 *
 27 **************************************************************************/
 28/*
 29 * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>
 30 */
 31
 32#define pr_fmt(fmt) "[TTM] " fmt
 33
 34#include <linux/sched.h>
 
 35#include <linux/pagemap.h>
 36#include <linux/shmem_fs.h>
 37#include <linux/file.h>
 
 
 
 38#include <drm/drm_cache.h>
 
 
 39#include <drm/ttm/ttm_bo_driver.h>
 
 
 40
 41#include "ttm_module.h"
 
 
 
 
 
 
 42
 43static unsigned long ttm_pages_limit;
 
 
 
 
 
 
 
 
 44
 45MODULE_PARM_DESC(pages_limit, "Limit for the allocated pages");
 46module_param_named(pages_limit, ttm_pages_limit, ulong, 0644);
 
 
 
 
 47
 48static unsigned long ttm_dma32_pages_limit;
 
 49
 50MODULE_PARM_DESC(dma32_pages_limit, "Limit for the allocated DMA32 pages");
 51module_param_named(dma32_pages_limit, ttm_dma32_pages_limit, ulong, 0644);
 
 52
 53static atomic_long_t ttm_pages_allocated;
 54static atomic_long_t ttm_dma32_pages_allocated;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 55
 56/*
 57 * Allocates a ttm structure for the given BO.
 
 58 */
 59int ttm_tt_create(struct ttm_buffer_object *bo, bool zero_alloc)
 
 
 60{
 61	struct ttm_device *bdev = bo->bdev;
 62	uint32_t page_flags = 0;
 
 63
 64	dma_resv_assert_held(bo->base.resv);
 
 65
 66	if (bo->ttm)
 
 
 67		return 0;
 
 
 
 
 68
 69	switch (bo->type) {
 70	case ttm_bo_type_device:
 71		if (zero_alloc)
 72			page_flags |= TTM_PAGE_FLAG_ZERO_ALLOC;
 73		break;
 74	case ttm_bo_type_kernel:
 75		break;
 76	case ttm_bo_type_sg:
 77		page_flags |= TTM_PAGE_FLAG_SG;
 78		break;
 79	default:
 80		pr_err("Illegal buffer object type\n");
 81		return -EINVAL;
 82	}
 83
 84	bo->ttm = bdev->funcs->ttm_tt_create(bo, page_flags);
 85	if (unlikely(bo->ttm == NULL))
 86		return -ENOMEM;
 87
 88	return 0;
 
 
 
 
 
 
 
 
 
 
 
 89}
 90
 91/*
 92 * Allocates storage for pointers to the pages that back the ttm.
 93 */
 94static int ttm_tt_alloc_page_directory(struct ttm_tt *ttm)
 95{
 96	ttm->pages = kvmalloc_array(ttm->num_pages, sizeof(void*),
 97			GFP_KERNEL | __GFP_ZERO);
 98	if (!ttm->pages)
 99		return -ENOMEM;
100	return 0;
101}
102
103static int ttm_dma_tt_alloc_page_directory(struct ttm_tt *ttm)
104{
105	ttm->pages = kvmalloc_array(ttm->num_pages,
106				    sizeof(*ttm->pages) +
107				    sizeof(*ttm->dma_address),
108				    GFP_KERNEL | __GFP_ZERO);
109	if (!ttm->pages)
110		return -ENOMEM;
111
112	ttm->dma_address = (void *)(ttm->pages + ttm->num_pages);
113	return 0;
114}
 
115
116static int ttm_sg_tt_alloc_page_directory(struct ttm_tt *ttm)
117{
118	ttm->dma_address = kvmalloc_array(ttm->num_pages,
119					  sizeof(*ttm->dma_address),
120					  GFP_KERNEL | __GFP_ZERO);
121	if (!ttm->dma_address)
122		return -ENOMEM;
123	return 0;
124}
125
126void ttm_tt_destroy_common(struct ttm_device *bdev, struct ttm_tt *ttm)
127{
128	ttm_tt_unpopulate(bdev, ttm);
129
130	if (ttm->swap_storage)
 
131		fput(ttm->swap_storage);
132
133	ttm->swap_storage = NULL;
 
134}
135EXPORT_SYMBOL(ttm_tt_destroy_common);
136
137void ttm_tt_destroy(struct ttm_device *bdev, struct ttm_tt *ttm)
 
 
138{
139	bdev->funcs->ttm_tt_destroy(bdev, ttm);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
140}
 
141
142static void ttm_tt_init_fields(struct ttm_tt *ttm,
143			       struct ttm_buffer_object *bo,
144			       uint32_t page_flags,
145			       enum ttm_caching caching)
146{
147	ttm->num_pages = PAGE_ALIGN(bo->base.size) >> PAGE_SHIFT;
148	ttm->caching = ttm_cached;
 
 
 
 
 
 
 
 
 
 
 
 
 
149	ttm->page_flags = page_flags;
150	ttm->dma_address = NULL;
 
151	ttm->swap_storage = NULL;
152	ttm->sg = bo->sg;
153	ttm->caching = caching;
154}
155
156int ttm_tt_init(struct ttm_tt *ttm, struct ttm_buffer_object *bo,
157		uint32_t page_flags, enum ttm_caching caching)
158{
159	ttm_tt_init_fields(ttm, bo, page_flags, caching);
160
161	if (ttm_tt_alloc_page_directory(ttm)) {
 
 
 
162		pr_err("Failed allocating page table\n");
163		return -ENOMEM;
164	}
165	return 0;
166}
167EXPORT_SYMBOL(ttm_tt_init);
168
169void ttm_tt_fini(struct ttm_tt *ttm)
170{
171	if (ttm->pages)
172		kvfree(ttm->pages);
173	else
174		kvfree(ttm->dma_address);
175	ttm->pages = NULL;
176	ttm->dma_address = NULL;
 
177}
178EXPORT_SYMBOL(ttm_tt_fini);
179
180int ttm_sg_tt_init(struct ttm_tt *ttm, struct ttm_buffer_object *bo,
181		   uint32_t page_flags, enum ttm_caching caching)
182{
183	int ret;
184
185	ttm_tt_init_fields(ttm, bo, page_flags, caching);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
186
187	if (page_flags & TTM_PAGE_FLAG_SG)
188		ret = ttm_sg_tt_alloc_page_directory(ttm);
189	else
190		ret = ttm_dma_tt_alloc_page_directory(ttm);
191	if (ret) {
192		pr_err("Failed allocating page table\n");
193		return -ENOMEM;
194	}
195	return 0;
196}
197EXPORT_SYMBOL(ttm_sg_tt_init);
198
199int ttm_tt_swapin(struct ttm_tt *ttm)
200{
201	struct address_space *swap_space;
202	struct file *swap_storage;
203	struct page *from_page;
204	struct page *to_page;
205	gfp_t gfp_mask;
206	int i, ret;
207
208	swap_storage = ttm->swap_storage;
209	BUG_ON(swap_storage == NULL);
210
211	swap_space = swap_storage->f_mapping;
212	gfp_mask = mapping_gfp_mask(swap_space);
213
214	for (i = 0; i < ttm->num_pages; ++i) {
215		from_page = shmem_read_mapping_page_gfp(swap_space, i,
216							gfp_mask);
217		if (IS_ERR(from_page)) {
218			ret = PTR_ERR(from_page);
219			goto out_err;
220		}
221		to_page = ttm->pages[i];
222		if (unlikely(to_page == NULL)) {
223			ret = -ENOMEM;
224			goto out_err;
225		}
226
227		copy_highpage(to_page, from_page);
228		put_page(from_page);
229	}
230
231	fput(swap_storage);
 
232	ttm->swap_storage = NULL;
233	ttm->page_flags &= ~TTM_PAGE_FLAG_SWAPPED;
234
235	return 0;
236
237out_err:
238	return ret;
239}
240
241/**
242 * ttm_tt_swapout - swap out tt object
243 *
244 * @bdev: TTM device structure.
245 * @ttm: The struct ttm_tt.
246 * @gfp_flags: Flags to use for memory allocation.
247 *
248 * Swapout a TT object to a shmem_file, return number of pages swapped out or
249 * negative error code.
250 */
251int ttm_tt_swapout(struct ttm_device *bdev, struct ttm_tt *ttm,
252		   gfp_t gfp_flags)
253{
254	loff_t size = (loff_t)ttm->num_pages << PAGE_SHIFT;
255	struct address_space *swap_space;
256	struct file *swap_storage;
257	struct page *from_page;
258	struct page *to_page;
259	int i, ret;
 
260
261	swap_storage = shmem_file_setup("ttm swap", size, 0);
262	if (IS_ERR(swap_storage)) {
263		pr_err("Failed allocating swap storage\n");
264		return PTR_ERR(swap_storage);
265	}
 
 
 
 
 
 
 
 
266
267	swap_space = swap_storage->f_mapping;
268	gfp_flags &= mapping_gfp_mask(swap_space);
269
270	for (i = 0; i < ttm->num_pages; ++i) {
271		from_page = ttm->pages[i];
272		if (unlikely(from_page == NULL))
273			continue;
274
275		to_page = shmem_read_mapping_page_gfp(swap_space, i, gfp_flags);
276		if (IS_ERR(to_page)) {
277			ret = PTR_ERR(to_page);
278			goto out_err;
279		}
280		copy_highpage(to_page, from_page);
281		set_page_dirty(to_page);
282		mark_page_accessed(to_page);
283		put_page(to_page);
284	}
285
286	ttm_tt_unpopulate(bdev, ttm);
287	ttm->swap_storage = swap_storage;
288	ttm->page_flags |= TTM_PAGE_FLAG_SWAPPED;
 
 
289
290	return ttm->num_pages;
291
292out_err:
293	fput(swap_storage);
 
294
295	return ret;
296}
297
298static void ttm_tt_add_mapping(struct ttm_device *bdev, struct ttm_tt *ttm)
299{
300	pgoff_t i;
301
302	if (ttm->page_flags & TTM_PAGE_FLAG_SG)
303		return;
304
305	for (i = 0; i < ttm->num_pages; ++i)
306		ttm->pages[i]->mapping = bdev->dev_mapping;
307}
308
309int ttm_tt_populate(struct ttm_device *bdev,
310		    struct ttm_tt *ttm, struct ttm_operation_ctx *ctx)
311{
312	int ret;
313
314	if (!ttm)
315		return -EINVAL;
316
317	if (ttm_tt_is_populated(ttm))
318		return 0;
319
320	if (!(ttm->page_flags & TTM_PAGE_FLAG_SG)) {
321		atomic_long_add(ttm->num_pages, &ttm_pages_allocated);
322		if (bdev->pool.use_dma32)
323			atomic_long_add(ttm->num_pages,
324					&ttm_dma32_pages_allocated);
325	}
326
327	while (atomic_long_read(&ttm_pages_allocated) > ttm_pages_limit ||
328	       atomic_long_read(&ttm_dma32_pages_allocated) >
329	       ttm_dma32_pages_limit) {
330
331		ret = ttm_global_swapout(ctx, GFP_KERNEL);
332		if (ret == 0)
333			break;
334		if (ret < 0)
335			goto error;
336	}
337
338	if (bdev->funcs->ttm_tt_populate)
339		ret = bdev->funcs->ttm_tt_populate(bdev, ttm, ctx);
340	else
341		ret = ttm_pool_alloc(&bdev->pool, ttm, ctx);
342	if (ret)
343		goto error;
344
345	ttm_tt_add_mapping(bdev, ttm);
346	ttm->page_flags |= TTM_PAGE_FLAG_PRIV_POPULATED;
347	if (unlikely(ttm->page_flags & TTM_PAGE_FLAG_SWAPPED)) {
348		ret = ttm_tt_swapin(ttm);
349		if (unlikely(ret != 0)) {
350			ttm_tt_unpopulate(bdev, ttm);
351			return ret;
352		}
353	}
354
355	return 0;
356
357error:
358	if (!(ttm->page_flags & TTM_PAGE_FLAG_SG)) {
359		atomic_long_sub(ttm->num_pages, &ttm_pages_allocated);
360		if (bdev->pool.use_dma32)
361			atomic_long_sub(ttm->num_pages,
362					&ttm_dma32_pages_allocated);
363	}
364	return ret;
365}
366EXPORT_SYMBOL(ttm_tt_populate);
367
368static void ttm_tt_clear_mapping(struct ttm_tt *ttm)
369{
370	pgoff_t i;
371	struct page **page = ttm->pages;
372
373	if (ttm->page_flags & TTM_PAGE_FLAG_SG)
374		return;
375
376	for (i = 0; i < ttm->num_pages; ++i) {
377		(*page)->mapping = NULL;
378		(*page++)->index = 0;
379	}
380}
381
382void ttm_tt_unpopulate(struct ttm_device *bdev, struct ttm_tt *ttm)
383{
384	if (!ttm_tt_is_populated(ttm))
385		return;
386
387	ttm_tt_clear_mapping(ttm);
388	if (bdev->funcs->ttm_tt_unpopulate)
389		bdev->funcs->ttm_tt_unpopulate(bdev, ttm);
390	else
391		ttm_pool_free(&bdev->pool, ttm);
392
393	if (!(ttm->page_flags & TTM_PAGE_FLAG_SG)) {
394		atomic_long_sub(ttm->num_pages, &ttm_pages_allocated);
395		if (bdev->pool.use_dma32)
396			atomic_long_sub(ttm->num_pages,
397					&ttm_dma32_pages_allocated);
398	}
399
400	ttm->page_flags &= ~TTM_PAGE_FLAG_PRIV_POPULATED;
401}
402
403#ifdef CONFIG_DEBUG_FS
404
405/* Test the shrinker functions and dump the result */
406static int ttm_tt_debugfs_shrink_show(struct seq_file *m, void *data)
407{
408	struct ttm_operation_ctx ctx = { false, false };
409
410	seq_printf(m, "%d\n", ttm_global_swapout(&ctx, GFP_KERNEL));
411	return 0;
412}
413DEFINE_SHOW_ATTRIBUTE(ttm_tt_debugfs_shrink);
414
415#endif
416
417
418/*
419 * ttm_tt_mgr_init - register with the MM shrinker
420 *
421 * Register with the MM shrinker for swapping out BOs.
422 */
423void ttm_tt_mgr_init(unsigned long num_pages, unsigned long num_dma32_pages)
424{
425#ifdef CONFIG_DEBUG_FS
426	debugfs_create_file("tt_shrink", 0400, ttm_debugfs_root, NULL,
427			    &ttm_tt_debugfs_shrink_fops);
428#endif
429
430	if (!ttm_pages_limit)
431		ttm_pages_limit = num_pages;
432
433	if (!ttm_dma32_pages_limit)
434		ttm_dma32_pages_limit = num_dma32_pages;
435}
436
437static void ttm_kmap_iter_tt_map_local(struct ttm_kmap_iter *iter,
438				       struct dma_buf_map *dmap,
439				       pgoff_t i)
440{
441	struct ttm_kmap_iter_tt *iter_tt =
442		container_of(iter, typeof(*iter_tt), base);
443
444	dma_buf_map_set_vaddr(dmap, kmap_local_page_prot(iter_tt->tt->pages[i],
445							 iter_tt->prot));
446}
447
448static void ttm_kmap_iter_tt_unmap_local(struct ttm_kmap_iter *iter,
449					 struct dma_buf_map *map)
450{
451	kunmap_local(map->vaddr);
452}
453
454static const struct ttm_kmap_iter_ops ttm_kmap_iter_tt_ops = {
455	.map_local = ttm_kmap_iter_tt_map_local,
456	.unmap_local = ttm_kmap_iter_tt_unmap_local,
457	.maps_tt = true,
458};
459
460/**
461 * ttm_kmap_iter_tt_init - Initialize a struct ttm_kmap_iter_tt
462 * @iter_tt: The struct ttm_kmap_iter_tt to initialize.
463 * @tt: Struct ttm_tt holding page pointers of the struct ttm_resource.
464 *
465 * Return: Pointer to the embedded struct ttm_kmap_iter.
466 */
467struct ttm_kmap_iter *
468ttm_kmap_iter_tt_init(struct ttm_kmap_iter_tt *iter_tt,
469		      struct ttm_tt *tt)
470{
471	iter_tt->base.ops = &ttm_kmap_iter_tt_ops;
472	iter_tt->tt = tt;
473	if (tt)
474		iter_tt->prot = ttm_prot_from_caching(tt->caching, PAGE_KERNEL);
475	else
476		iter_tt->prot = PAGE_KERNEL;
477
478	return &iter_tt->base;
479}
480EXPORT_SYMBOL(ttm_kmap_iter_tt_init);