Bootlin logo

Elixir Cross Referencer

  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
/*
 * drivers/staging/android/ion/ion_system_heap.c
 *
 * Copyright (C) 2011 Google, Inc.
 *
 * This software is licensed under the terms of the GNU General Public
 * License version 2, as published by the Free Software Foundation, and
 * may be copied, distributed, and modified under those terms.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 */

#include <asm/page.h>
#include <linux/dma-mapping.h>
#include <linux/err.h>
#include <linux/highmem.h>
#include <linux/mm.h>
#include <linux/scatterlist.h>
#include <linux/seq_file.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include "ion.h"
#include "ion_priv.h"

static gfp_t high_order_gfp_flags = (GFP_HIGHUSER | __GFP_ZERO | __GFP_NOWARN |
				     __GFP_NORETRY) & ~__GFP_RECLAIM;
static gfp_t low_order_gfp_flags  = (GFP_HIGHUSER | __GFP_ZERO | __GFP_NOWARN);
static const unsigned int orders[] = {8, 4, 0};
static const int num_orders = ARRAY_SIZE(orders);
static int order_to_index(unsigned int order)
{
	int i;

	for (i = 0; i < num_orders; i++)
		if (order == orders[i])
			return i;
	BUG();
	return -1;
}

static inline unsigned int order_to_size(int order)
{
	return PAGE_SIZE << order;
}

struct ion_system_heap {
	struct ion_heap heap;
	struct ion_page_pool *pools[0];
};

static struct page *alloc_buffer_page(struct ion_system_heap *heap,
				      struct ion_buffer *buffer,
				      unsigned long order)
{
	bool cached = ion_buffer_cached(buffer);
	struct ion_page_pool *pool = heap->pools[order_to_index(order)];
	struct page *page;

	if (!cached) {
		page = ion_page_pool_alloc(pool);
	} else {
		gfp_t gfp_flags = low_order_gfp_flags;

		if (order > 4)
			gfp_flags = high_order_gfp_flags;
		page = alloc_pages(gfp_flags | __GFP_COMP, order);
		if (!page)
			return NULL;
		ion_pages_sync_for_device(NULL, page, PAGE_SIZE << order,
						DMA_BIDIRECTIONAL);
	}

	return page;
}

static void free_buffer_page(struct ion_system_heap *heap,
			     struct ion_buffer *buffer, struct page *page)
{
	unsigned int order = compound_order(page);
	bool cached = ion_buffer_cached(buffer);

	if (!cached && !(buffer->private_flags & ION_PRIV_FLAG_SHRINKER_FREE)) {
		struct ion_page_pool *pool = heap->pools[order_to_index(order)];

		ion_page_pool_free(pool, page);
	} else {
		__free_pages(page, order);
	}
}


static struct page *alloc_largest_available(struct ion_system_heap *heap,
					    struct ion_buffer *buffer,
					    unsigned long size,
					    unsigned int max_order)
{
	struct page *page;
	int i;

	for (i = 0; i < num_orders; i++) {
		if (size < order_to_size(orders[i]))
			continue;
		if (max_order < orders[i])
			continue;

		page = alloc_buffer_page(heap, buffer, orders[i]);
		if (!page)
			continue;

		return page;
	}

	return NULL;
}

static int ion_system_heap_allocate(struct ion_heap *heap,
				     struct ion_buffer *buffer,
				     unsigned long size, unsigned long align,
				     unsigned long flags)
{
	struct ion_system_heap *sys_heap = container_of(heap,
							struct ion_system_heap,
							heap);
	struct sg_table *table;
	struct scatterlist *sg;
	struct list_head pages;
	struct page *page, *tmp_page;
	int i = 0;
	unsigned long size_remaining = PAGE_ALIGN(size);
	unsigned int max_order = orders[0];

	if (align > PAGE_SIZE)
		return -EINVAL;

	if (size / PAGE_SIZE > totalram_pages / 2)
		return -ENOMEM;

	INIT_LIST_HEAD(&pages);
	while (size_remaining > 0) {
		page = alloc_largest_available(sys_heap, buffer, size_remaining,
						max_order);
		if (!page)
			goto free_pages;
		list_add_tail(&page->lru, &pages);
		size_remaining -= PAGE_SIZE << compound_order(page);
		max_order = compound_order(page);
		i++;
	}
	table = kmalloc(sizeof(struct sg_table), GFP_KERNEL);
	if (!table)
		goto free_pages;

	if (sg_alloc_table(table, i, GFP_KERNEL))
		goto free_table;

	sg = table->sgl;
	list_for_each_entry_safe(page, tmp_page, &pages, lru) {
		sg_set_page(sg, page, PAGE_SIZE << compound_order(page), 0);
		sg = sg_next(sg);
		list_del(&page->lru);
	}

	buffer->priv_virt = table;
	return 0;

free_table:
	kfree(table);
free_pages:
	list_for_each_entry_safe(page, tmp_page, &pages, lru)
		free_buffer_page(sys_heap, buffer, page);
	return -ENOMEM;
}

static void ion_system_heap_free(struct ion_buffer *buffer)
{
	struct ion_system_heap *sys_heap = container_of(buffer->heap,
							struct ion_system_heap,
							heap);
	struct sg_table *table = buffer->sg_table;
	bool cached = ion_buffer_cached(buffer);
	struct scatterlist *sg;
	int i;

	/*
	 *  uncached pages come from the page pools, zero them before returning
	 *  for security purposes (other allocations are zerod at
	 *  alloc time
	 */
	if (!cached && !(buffer->private_flags & ION_PRIV_FLAG_SHRINKER_FREE))
		ion_heap_buffer_zero(buffer);

	for_each_sg(table->sgl, sg, table->nents, i)
		free_buffer_page(sys_heap, buffer, sg_page(sg));
	sg_free_table(table);
	kfree(table);
}

static struct sg_table *ion_system_heap_map_dma(struct ion_heap *heap,
						struct ion_buffer *buffer)
{
	return buffer->priv_virt;
}

static void ion_system_heap_unmap_dma(struct ion_heap *heap,
				      struct ion_buffer *buffer)
{
}

static int ion_system_heap_shrink(struct ion_heap *heap, gfp_t gfp_mask,
					int nr_to_scan)
{
	struct ion_system_heap *sys_heap;
	int nr_total = 0;
	int i, nr_freed;
	int only_scan = 0;

	sys_heap = container_of(heap, struct ion_system_heap, heap);

	if (!nr_to_scan)
		only_scan = 1;

	for (i = 0; i < num_orders; i++) {
		struct ion_page_pool *pool = sys_heap->pools[i];

		nr_freed = ion_page_pool_shrink(pool, gfp_mask, nr_to_scan);
		nr_total += nr_freed;

		if (!only_scan) {
			nr_to_scan -= nr_freed;
			/* shrink completed */
			if (nr_to_scan <= 0)
				break;
		}
	}

	return nr_total;
}

static struct ion_heap_ops system_heap_ops = {
	.allocate = ion_system_heap_allocate,
	.free = ion_system_heap_free,
	.map_dma = ion_system_heap_map_dma,
	.unmap_dma = ion_system_heap_unmap_dma,
	.map_kernel = ion_heap_map_kernel,
	.unmap_kernel = ion_heap_unmap_kernel,
	.map_user = ion_heap_map_user,
	.shrink = ion_system_heap_shrink,
};

static int ion_system_heap_debug_show(struct ion_heap *heap, struct seq_file *s,
				      void *unused)
{

	struct ion_system_heap *sys_heap = container_of(heap,
							struct ion_system_heap,
							heap);
	int i;

	for (i = 0; i < num_orders; i++) {
		struct ion_page_pool *pool = sys_heap->pools[i];

		seq_printf(s, "%d order %u highmem pages in pool = %lu total\n",
			   pool->high_count, pool->order,
			   (PAGE_SIZE << pool->order) * pool->high_count);
		seq_printf(s, "%d order %u lowmem pages in pool = %lu total\n",
			   pool->low_count, pool->order,
			   (PAGE_SIZE << pool->order) * pool->low_count);
	}
	return 0;
}

struct ion_heap *ion_system_heap_create(struct ion_platform_heap *unused)
{
	struct ion_system_heap *heap;
	int i;

	heap = kzalloc(sizeof(struct ion_system_heap) +
			sizeof(struct ion_page_pool *) * num_orders,
			GFP_KERNEL);
	if (!heap)
		return ERR_PTR(-ENOMEM);
	heap->heap.ops = &system_heap_ops;
	heap->heap.type = ION_HEAP_TYPE_SYSTEM;
	heap->heap.flags = ION_HEAP_FLAG_DEFER_FREE;

	for (i = 0; i < num_orders; i++) {
		struct ion_page_pool *pool;
		gfp_t gfp_flags = low_order_gfp_flags;

		if (orders[i] > 4)
			gfp_flags = high_order_gfp_flags;
		pool = ion_page_pool_create(gfp_flags, orders[i]);
		if (!pool)
			goto destroy_pools;
		heap->pools[i] = pool;
	}

	heap->heap.debug_show = ion_system_heap_debug_show;
	return &heap->heap;

destroy_pools:
	while (i--)
		ion_page_pool_destroy(heap->pools[i]);
	kfree(heap);
	return ERR_PTR(-ENOMEM);
}

void ion_system_heap_destroy(struct ion_heap *heap)
{
	struct ion_system_heap *sys_heap = container_of(heap,
							struct ion_system_heap,
							heap);
	int i;

	for (i = 0; i < num_orders; i++)
		ion_page_pool_destroy(sys_heap->pools[i]);
	kfree(sys_heap);
}

static int ion_system_contig_heap_allocate(struct ion_heap *heap,
					   struct ion_buffer *buffer,
					   unsigned long len,
					   unsigned long align,
					   unsigned long flags)
{
	int order = get_order(len);
	struct page *page;
	struct sg_table *table;
	unsigned long i;
	int ret;

	if (align > (PAGE_SIZE << order))
		return -EINVAL;

	page = alloc_pages(low_order_gfp_flags, order);
	if (!page)
		return -ENOMEM;

	split_page(page, order);

	len = PAGE_ALIGN(len);
	for (i = len >> PAGE_SHIFT; i < (1 << order); i++)
		__free_page(page + i);

	table = kmalloc(sizeof(struct sg_table), GFP_KERNEL);
	if (!table) {
		ret = -ENOMEM;
		goto free_pages;
	}

	ret = sg_alloc_table(table, 1, GFP_KERNEL);
	if (ret)
		goto free_table;

	sg_set_page(table->sgl, page, len, 0);

	buffer->priv_virt = table;

	ion_pages_sync_for_device(NULL, page, len, DMA_BIDIRECTIONAL);

	return 0;

free_table:
	kfree(table);
free_pages:
	for (i = 0; i < len >> PAGE_SHIFT; i++)
		__free_page(page + i);

	return ret;
}

static void ion_system_contig_heap_free(struct ion_buffer *buffer)
{
	struct sg_table *table = buffer->priv_virt;
	struct page *page = sg_page(table->sgl);
	unsigned long pages = PAGE_ALIGN(buffer->size) >> PAGE_SHIFT;
	unsigned long i;

	for (i = 0; i < pages; i++)
		__free_page(page + i);
	sg_free_table(table);
	kfree(table);
}

static int ion_system_contig_heap_phys(struct ion_heap *heap,
				       struct ion_buffer *buffer,
				       ion_phys_addr_t *addr, size_t *len)
{
	struct sg_table *table = buffer->priv_virt;
	struct page *page = sg_page(table->sgl);
	*addr = page_to_phys(page);
	*len = buffer->size;
	return 0;
}

static struct sg_table *ion_system_contig_heap_map_dma(struct ion_heap *heap,
						struct ion_buffer *buffer)
{
	return buffer->priv_virt;
}

static void ion_system_contig_heap_unmap_dma(struct ion_heap *heap,
					     struct ion_buffer *buffer)
{
}

static struct ion_heap_ops kmalloc_ops = {
	.allocate = ion_system_contig_heap_allocate,
	.free = ion_system_contig_heap_free,
	.phys = ion_system_contig_heap_phys,
	.map_dma = ion_system_contig_heap_map_dma,
	.unmap_dma = ion_system_contig_heap_unmap_dma,
	.map_kernel = ion_heap_map_kernel,
	.unmap_kernel = ion_heap_unmap_kernel,
	.map_user = ion_heap_map_user,
};

struct ion_heap *ion_system_contig_heap_create(struct ion_platform_heap *unused)
{
	struct ion_heap *heap;

	heap = kzalloc(sizeof(struct ion_heap), GFP_KERNEL);
	if (!heap)
		return ERR_PTR(-ENOMEM);
	heap->ops = &kmalloc_ops;
	heap->type = ION_HEAP_TYPE_SYSTEM_CONTIG;
	return heap;
}

void ion_system_contig_heap_destroy(struct ion_heap *heap)
{
	kfree(heap);
}