ion_system_heap.c revision b6152016003b2cc2370899558bf2e7de4ebd0b09 
1/*
2 * drivers/staging/android/ion/ion_system_heap.c
3 *
4 * Copyright (C) 2011 Google, Inc.
5 *
6 * This software is licensed under the terms of the GNU General Public
7 * License version 2, as published by the Free Software Foundation, and
8 * may be copied, distributed, and modified under those terms.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13 * GNU General Public License for more details.
14 *
15 */
16
17#include <asm/page.h>
18#include <linux/dma-mapping.h>
19#include <linux/err.h>
20#include <linux/highmem.h>
21#include <linux/mm.h>
22#include <linux/scatterlist.h>
23#include <linux/seq_file.h>
24#include <linux/slab.h>
25#include <linux/vmalloc.h>
26#include "ion.h"
27#include "ion_priv.h"
28
29static gfp_t high_order_gfp_flags = (GFP_HIGHUSER | __GFP_ZERO | __GFP_NOWARN |
30				     __GFP_NORETRY) & ~__GFP_WAIT;
31static gfp_t low_order_gfp_flags  = (GFP_HIGHUSER | __GFP_ZERO | __GFP_NOWARN);
32static const unsigned int orders[] = {8, 4, 0};
33static const int num_orders = ARRAY_SIZE(orders);
34static int order_to_index(unsigned int order)
35{
36	int i;
37	for (i = 0; i < num_orders; i++)
38		if (order == orders[i])
39			return i;
40	BUG();
41	return -1;
42}
43
44static unsigned int order_to_size(int order)
45{
46	return PAGE_SIZE << order;
47}
48
49struct ion_system_heap {
50	struct ion_heap heap;
51	struct ion_page_pool **pools;
52};
53
54struct page_info {
55	struct page *page;
56	unsigned int order;
57	struct list_head list;
58};
59
60static struct page *alloc_buffer_page(struct ion_system_heap *heap,
61				      struct ion_buffer *buffer,
62				      unsigned long order)
63{
64	bool cached = ion_buffer_cached(buffer);
65	struct ion_page_pool *pool = heap->pools[order_to_index(order)];
66	struct page *page;
67
68	if (!cached) {
69		page = ion_page_pool_alloc(pool);
70	} else {
71		gfp_t gfp_flags = low_order_gfp_flags;
72
73		if (order > 4)
74			gfp_flags = high_order_gfp_flags;
75		page = alloc_pages(gfp_flags, order);
76		if (!page)
77			return NULL;
78		ion_pages_sync_for_device(NULL, page, PAGE_SIZE << order,
79						DMA_BIDIRECTIONAL);
80	}
81	if (!page)
82		return NULL;
83
84	return page;
85}
86
87static void free_buffer_page(struct ion_system_heap *heap,
88			     struct ion_buffer *buffer, struct page *page,
89			     unsigned int order)
90{
91	bool cached = ion_buffer_cached(buffer);
92
93	if (!cached && !(buffer->private_flags & ION_PRIV_FLAG_SHRINKER_FREE)) {
94		struct ion_page_pool *pool = heap->pools[order_to_index(order)];
95		ion_page_pool_free(pool, page);
96	} else {
97		__free_pages(page, order);
98	}
99}
100
101
102static struct page_info *alloc_largest_available(struct ion_system_heap *heap,
103						 struct ion_buffer *buffer,
104						 unsigned long size,
105						 unsigned int max_order)
106{
107	struct page *page;
108	struct page_info *info;
109	int i;
110
111	info = kmalloc(sizeof(struct page_info), GFP_KERNEL);
112	if (!info)
113		return NULL;
114
115	for (i = 0; i < num_orders; i++) {
116		if (size < order_to_size(orders[i]))
117			continue;
118		if (max_order < orders[i])
119			continue;
120
121		page = alloc_buffer_page(heap, buffer, orders[i]);
122		if (!page)
123			continue;
124
125		info->page = page;
126		info->order = orders[i];
127		INIT_LIST_HEAD(&info->list);
128		return info;
129	}
130	kfree(info);
131
132	return NULL;
133}
134
135static int ion_system_heap_allocate(struct ion_heap *heap,
136				     struct ion_buffer *buffer,
137				     unsigned long size, unsigned long align,
138				     unsigned long flags)
139{
140	struct ion_system_heap *sys_heap = container_of(heap,
141							struct ion_system_heap,
142							heap);
143	struct sg_table *table;
144	struct scatterlist *sg;
145	int ret;
146	struct list_head pages;
147	struct page_info *info, *tmp_info;
148	int i = 0;
149	unsigned long size_remaining = PAGE_ALIGN(size);
150	unsigned int max_order = orders[0];
151
152	if (align > PAGE_SIZE)
153		return -EINVAL;
154
155	if (size / PAGE_SIZE > totalram_pages / 2)
156		return -ENOMEM;
157
158	INIT_LIST_HEAD(&pages);
159	while (size_remaining > 0) {
160		info = alloc_largest_available(sys_heap, buffer, size_remaining,
161						max_order);
162		if (!info)
163			goto err;
164		list_add_tail(&info->list, &pages);
165		size_remaining -= (1 << info->order) * PAGE_SIZE;
166		max_order = info->order;
167		i++;
168	}
169	table = kmalloc(sizeof(struct sg_table), GFP_KERNEL);
170	if (!table)
171		goto err;
172
173	ret = sg_alloc_table(table, i, GFP_KERNEL);
174	if (ret)
175		goto err1;
176
177	sg = table->sgl;
178	list_for_each_entry_safe(info, tmp_info, &pages, list) {
179		struct page *page = info->page;
180		sg_set_page(sg, page, (1 << info->order) * PAGE_SIZE, 0);
181		sg = sg_next(sg);
182		list_del(&info->list);
183		kfree(info);
184	}
185
186	buffer->priv_virt = table;
187	return 0;
188err1:
189	kfree(table);
190err:
191	list_for_each_entry_safe(info, tmp_info, &pages, list) {
192		free_buffer_page(sys_heap, buffer, info->page, info->order);
193		kfree(info);
194	}
195	return -ENOMEM;
196}
197
198static void ion_system_heap_free(struct ion_buffer *buffer)
199{
200	struct ion_heap *heap = buffer->heap;
201	struct ion_system_heap *sys_heap = container_of(heap,
202							struct ion_system_heap,
203							heap);
204	struct sg_table *table = buffer->sg_table;
205	bool cached = ion_buffer_cached(buffer);
206	struct scatterlist *sg;
207	LIST_HEAD(pages);
208	int i;
209
210	/* uncached pages come from the page pools, zero them before returning
211	   for security purposes (other allocations are zerod at alloc time */
212	if (!cached && !(buffer->private_flags & ION_PRIV_FLAG_SHRINKER_FREE))
213		ion_heap_buffer_zero(buffer);
214
215	for_each_sg(table->sgl, sg, table->nents, i)
216		free_buffer_page(sys_heap, buffer, sg_page(sg),
217				get_order(sg->length));
218	sg_free_table(table);
219	kfree(table);
220}
221
222static struct sg_table *ion_system_heap_map_dma(struct ion_heap *heap,
223						struct ion_buffer *buffer)
224{
225	return buffer->priv_virt;
226}
227
228static void ion_system_heap_unmap_dma(struct ion_heap *heap,
229				      struct ion_buffer *buffer)
230{
231	return;
232}
233
234static int ion_system_heap_shrink(struct ion_heap *heap, gfp_t gfp_mask,
235					int nr_to_scan)
236{
237	struct ion_system_heap *sys_heap;
238	int nr_total = 0;
239	int i;
240
241	sys_heap = container_of(heap, struct ion_system_heap, heap);
242
243	for (i = 0; i < num_orders; i++) {
244		struct ion_page_pool *pool = sys_heap->pools[i];
245		nr_total += ion_page_pool_shrink(pool, gfp_mask, nr_to_scan);
246	}
247
248	return nr_total;
249}
250
251static struct ion_heap_ops system_heap_ops = {
252	.allocate = ion_system_heap_allocate,
253	.free = ion_system_heap_free,
254	.map_dma = ion_system_heap_map_dma,
255	.unmap_dma = ion_system_heap_unmap_dma,
256	.map_kernel = ion_heap_map_kernel,
257	.unmap_kernel = ion_heap_unmap_kernel,
258	.map_user = ion_heap_map_user,
259	.shrink = ion_system_heap_shrink,
260};
261
262static int ion_system_heap_debug_show(struct ion_heap *heap, struct seq_file *s,
263				      void *unused)
264{
265
266	struct ion_system_heap *sys_heap = container_of(heap,
267							struct ion_system_heap,
268							heap);
269	int i;
270	for (i = 0; i < num_orders; i++) {
271		struct ion_page_pool *pool = sys_heap->pools[i];
272		seq_printf(s, "%d order %u highmem pages in pool = %lu total\n",
273			   pool->high_count, pool->order,
274			   (1 << pool->order) * PAGE_SIZE * pool->high_count);
275		seq_printf(s, "%d order %u lowmem pages in pool = %lu total\n",
276			   pool->low_count, pool->order,
277			   (1 << pool->order) * PAGE_SIZE * pool->low_count);
278	}
279	return 0;
280}
281
282struct ion_heap *ion_system_heap_create(struct ion_platform_heap *unused)
283{
284	struct ion_system_heap *heap;
285	int i;
286
287	heap = kzalloc(sizeof(struct ion_system_heap), GFP_KERNEL);
288	if (!heap)
289		return ERR_PTR(-ENOMEM);
290	heap->heap.ops = &system_heap_ops;
291	heap->heap.type = ION_HEAP_TYPE_SYSTEM;
292	heap->heap.flags = ION_HEAP_FLAG_DEFER_FREE;
293	heap->pools = kzalloc(sizeof(struct ion_page_pool *) * num_orders,
294			      GFP_KERNEL);
295	if (!heap->pools)
296		goto err_alloc_pools;
297	for (i = 0; i < num_orders; i++) {
298		struct ion_page_pool *pool;
299		gfp_t gfp_flags = low_order_gfp_flags;
300
301		if (orders[i] > 4)
302			gfp_flags = high_order_gfp_flags;
303		pool = ion_page_pool_create(gfp_flags, orders[i]);
304		if (!pool)
305			goto err_create_pool;
306		heap->pools[i] = pool;
307	}
308
309	heap->heap.debug_show = ion_system_heap_debug_show;
310	return &heap->heap;
311err_create_pool:
312	for (i = 0; i < num_orders; i++)
313		if (heap->pools[i])
314			ion_page_pool_destroy(heap->pools[i]);
315	kfree(heap->pools);
316err_alloc_pools:
317	kfree(heap);
318	return ERR_PTR(-ENOMEM);
319}
320
321void ion_system_heap_destroy(struct ion_heap *heap)
322{
323	struct ion_system_heap *sys_heap = container_of(heap,
324							struct ion_system_heap,
325							heap);
326	int i;
327
328	for (i = 0; i < num_orders; i++)
329		ion_page_pool_destroy(sys_heap->pools[i]);
330	kfree(sys_heap->pools);
331	kfree(sys_heap);
332}
333
334static int ion_system_contig_heap_allocate(struct ion_heap *heap,
335					   struct ion_buffer *buffer,
336					   unsigned long len,
337					   unsigned long align,
338					   unsigned long flags)
339{
340	int order = get_order(len);
341	struct page *page;
342	struct sg_table *table;
343	unsigned long i;
344	int ret;
345
346	if (align > (PAGE_SIZE << order))
347		return -EINVAL;
348
349	page = alloc_pages(low_order_gfp_flags, order);
350	if (!page)
351		return -ENOMEM;
352
353	split_page(page, order);
354
355	len = PAGE_ALIGN(len);
356	for (i = len >> PAGE_SHIFT; i < (1 << order); i++)
357		__free_page(page + i);
358
359	table = kmalloc(sizeof(struct sg_table), GFP_KERNEL);
360	if (!table) {
361		ret = -ENOMEM;
362		goto out;
363	}
364
365	ret = sg_alloc_table(table, 1, GFP_KERNEL);
366	if (ret)
367		goto out;
368
369	sg_set_page(table->sgl, page, len, 0);
370
371	buffer->priv_virt = table;
372
373	ion_pages_sync_for_device(NULL, page, len, DMA_BIDIRECTIONAL);
374
375	return 0;
376
377out:
378	for (i = 0; i < len >> PAGE_SHIFT; i++)
379		__free_page(page + i);
380	kfree(table);
381	return ret;
382}
383
384static void ion_system_contig_heap_free(struct ion_buffer *buffer)
385{
386	struct sg_table *table = buffer->priv_virt;
387	struct page *page = sg_page(table->sgl);
388	unsigned long pages = PAGE_ALIGN(buffer->size) >> PAGE_SHIFT;
389	unsigned long i;
390
391	for (i = 0; i < pages; i++)
392		__free_page(page + i);
393	sg_free_table(table);
394	kfree(table);
395}
396
397static int ion_system_contig_heap_phys(struct ion_heap *heap,
398				       struct ion_buffer *buffer,
399				       ion_phys_addr_t *addr, size_t *len)
400{
401	struct sg_table *table = buffer->priv_virt;
402	struct page *page = sg_page(table->sgl);
403	*addr = page_to_phys(page);
404	*len = buffer->size;
405	return 0;
406}
407
408static struct sg_table *ion_system_contig_heap_map_dma(struct ion_heap *heap,
409						struct ion_buffer *buffer)
410{
411	return buffer->priv_virt;
412}
413
414static void ion_system_contig_heap_unmap_dma(struct ion_heap *heap,
415					     struct ion_buffer *buffer)
416{
417}
418
419static struct ion_heap_ops kmalloc_ops = {
420	.allocate = ion_system_contig_heap_allocate,
421	.free = ion_system_contig_heap_free,
422	.phys = ion_system_contig_heap_phys,
423	.map_dma = ion_system_contig_heap_map_dma,
424	.unmap_dma = ion_system_contig_heap_unmap_dma,
425	.map_kernel = ion_heap_map_kernel,
426	.unmap_kernel = ion_heap_unmap_kernel,
427	.map_user = ion_heap_map_user,
428};
429
430struct ion_heap *ion_system_contig_heap_create(struct ion_platform_heap *unused)
431{
432	struct ion_heap *heap;
433
434	heap = kzalloc(sizeof(struct ion_heap), GFP_KERNEL);
435	if (!heap)
436		return ERR_PTR(-ENOMEM);
437	heap->ops = &kmalloc_ops;
438	heap->type = ION_HEAP_TYPE_SYSTEM_CONTIG;
439	return heap;
440}
441
442void ion_system_contig_heap_destroy(struct ion_heap *heap)
443{
444	kfree(heap);
445}
446
447