ion_system_heap.c revision 13ba7805f9bf710016ffde5e24437fd6e5a798dc 
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/slab.h>
24#include <linux/vmalloc.h>
25#include "ion.h"
26#include "ion_priv.h"
27
28struct page_info {
29	struct page *page;
30	unsigned long order;
31	struct list_head list;
32};
33
34static struct page_info *alloc_largest_available(unsigned long size,
35						 bool split_pages)
36{
37	static unsigned int orders[] = {8, 4, 0};
38	struct page *page;
39	struct page_info *info;
40	int i;
41
42	for (i = 0; i < ARRAY_SIZE(orders); i++) {
43		if (size < (1 << orders[i]) * PAGE_SIZE)
44			continue;
45		page = alloc_pages(GFP_HIGHUSER | __GFP_ZERO |
46				   __GFP_NOWARN | __GFP_NORETRY, orders[i]);
47		if (!page)
48			continue;
49		if (split_pages)
50			split_page(page, orders[i]);
51		info = kmalloc(sizeof(struct page_info *), GFP_KERNEL);
52		info->page = page;
53		info->order = orders[i];
54		return info;
55	}
56	return NULL;
57}
58
59static int ion_system_heap_allocate(struct ion_heap *heap,
60				     struct ion_buffer *buffer,
61				     unsigned long size, unsigned long align,
62				     unsigned long flags)
63{
64	struct sg_table *table;
65	struct scatterlist *sg;
66	int ret;
67	struct list_head pages;
68	struct page_info *info, *tmp_info;
69	int i = 0;
70	long size_remaining = PAGE_ALIGN(size);
71	bool split_pages = ion_buffer_fault_user_mappings(buffer);
72
73
74	INIT_LIST_HEAD(&pages);
75	while (size_remaining > 0) {
76		info = alloc_largest_available(size_remaining, split_pages);
77		if (!info)
78			goto err;
79		list_add_tail(&info->list, &pages);
80		size_remaining -= (1 << info->order) * PAGE_SIZE;
81		i++;
82	}
83
84	table = kmalloc(sizeof(struct sg_table), GFP_KERNEL);
85	if (!table)
86		goto err;
87
88	if (split_pages)
89		ret = sg_alloc_table(table, PAGE_ALIGN(size) / PAGE_SIZE,
90				     GFP_KERNEL);
91	else
92		ret = sg_alloc_table(table, i, GFP_KERNEL);
93
94	if (ret)
95		goto err1;
96
97	sg = table->sgl;
98	list_for_each_entry_safe(info, tmp_info, &pages, list) {
99		struct page *page = info->page;
100
101		if (split_pages) {
102			for (i = 0; i < (1 << info->order); i++) {
103				sg_set_page(sg, page + i, PAGE_SIZE, 0);
104				sg = sg_next(sg);
105			}
106		} else {
107			sg_set_page(sg, page, (1 << info->order) * PAGE_SIZE,
108				    0);
109			sg = sg_next(sg);
110		}
111		list_del(&info->list);
112		kfree(info);
113	}
114
115	dma_sync_sg_for_device(NULL, table->sgl, table->nents,
116			       DMA_BIDIRECTIONAL);
117
118	buffer->priv_virt = table;
119	return 0;
120err1:
121	kfree(table);
122err:
123	list_for_each_entry(info, &pages, list) {
124		if (split_pages)
125			for (i = 0; i < (1 << info->order); i++)
126				__free_page(info->page + i);
127		else
128			__free_pages(info->page, info->order);
129
130		kfree(info);
131	}
132	return -ENOMEM;
133}
134
135void ion_system_heap_free(struct ion_buffer *buffer)
136{
137	int i;
138	struct scatterlist *sg;
139	struct sg_table *table = buffer->priv_virt;
140
141	for_each_sg(table->sgl, sg, table->nents, i)
142		__free_pages(sg_page(sg), get_order(sg_dma_len(sg)));
143	if (buffer->sg_table)
144		sg_free_table(buffer->sg_table);
145	kfree(buffer->sg_table);
146}
147
148struct sg_table *ion_system_heap_map_dma(struct ion_heap *heap,
149					 struct ion_buffer *buffer)
150{
151	return buffer->priv_virt;
152}
153
154void ion_system_heap_unmap_dma(struct ion_heap *heap,
155			       struct ion_buffer *buffer)
156{
157	return;
158}
159
160void *ion_system_heap_map_kernel(struct ion_heap *heap,
161				 struct ion_buffer *buffer)
162{
163	struct scatterlist *sg;
164	int i, j;
165	void *vaddr;
166	pgprot_t pgprot;
167	struct sg_table *table = buffer->priv_virt;
168	int npages = PAGE_ALIGN(buffer->size) / PAGE_SIZE;
169	struct page **pages = kzalloc(sizeof(struct page *) * npages,
170				     GFP_KERNEL);
171	struct page **tmp = pages;
172
173	if (buffer->flags & ION_FLAG_CACHED)
174		pgprot = PAGE_KERNEL;
175	else
176		pgprot = pgprot_writecombine(PAGE_KERNEL);
177
178	for_each_sg(table->sgl, sg, table->nents, i) {
179		int npages_this_entry = PAGE_ALIGN(sg_dma_len(sg)) / PAGE_SIZE;
180		struct page *page = sg_page(sg);
181		BUG_ON(i >= npages);
182		for (j = 0; j < npages_this_entry; j++) {
183			*(tmp++) = page++;
184		}
185	}
186	vaddr = vmap(pages, npages, VM_MAP, pgprot);
187	kfree(pages);
188
189	return vaddr;
190}
191
192void ion_system_heap_unmap_kernel(struct ion_heap *heap,
193				  struct ion_buffer *buffer)
194{
195	vunmap(buffer->vaddr);
196}
197
198int ion_system_heap_map_user(struct ion_heap *heap, struct ion_buffer *buffer,
199			     struct vm_area_struct *vma)
200{
201	struct sg_table *table = buffer->priv_virt;
202	unsigned long addr = vma->vm_start;
203	unsigned long offset = vma->vm_pgoff;
204	struct scatterlist *sg;
205	int i;
206
207	for_each_sg(table->sgl, sg, table->nents, i) {
208		if (offset) {
209			offset--;
210			continue;
211		}
212		remap_pfn_range(vma, addr, page_to_pfn(sg_page(sg)),
213				sg_dma_len(sg), vma->vm_page_prot);
214		addr += sg_dma_len(sg);
215		if (addr >= vma->vm_end)
216			return 0;
217	}
218	return 0;
219}
220
221static struct ion_heap_ops vmalloc_ops = {
222	.allocate = ion_system_heap_allocate,
223	.free = ion_system_heap_free,
224	.map_dma = ion_system_heap_map_dma,
225	.unmap_dma = ion_system_heap_unmap_dma,
226	.map_kernel = ion_system_heap_map_kernel,
227	.unmap_kernel = ion_system_heap_unmap_kernel,
228	.map_user = ion_system_heap_map_user,
229};
230
231struct ion_heap *ion_system_heap_create(struct ion_platform_heap *unused)
232{
233	struct ion_heap *heap;
234
235	heap = kzalloc(sizeof(struct ion_heap), GFP_KERNEL);
236	if (!heap)
237		return ERR_PTR(-ENOMEM);
238	heap->ops = &vmalloc_ops;
239	heap->type = ION_HEAP_TYPE_SYSTEM;
240	return heap;
241}
242
243void ion_system_heap_destroy(struct ion_heap *heap)
244{
245	kfree(heap);
246}
247
248static int ion_system_contig_heap_allocate(struct ion_heap *heap,
249					   struct ion_buffer *buffer,
250					   unsigned long len,
251					   unsigned long align,
252					   unsigned long flags)
253{
254	buffer->priv_virt = kzalloc(len, GFP_KERNEL);
255	if (!buffer->priv_virt)
256		return -ENOMEM;
257	return 0;
258}
259
260void ion_system_contig_heap_free(struct ion_buffer *buffer)
261{
262	kfree(buffer->priv_virt);
263}
264
265static int ion_system_contig_heap_phys(struct ion_heap *heap,
266				       struct ion_buffer *buffer,
267				       ion_phys_addr_t *addr, size_t *len)
268{
269	*addr = virt_to_phys(buffer->priv_virt);
270	*len = buffer->size;
271	return 0;
272}
273
274struct sg_table *ion_system_contig_heap_map_dma(struct ion_heap *heap,
275						struct ion_buffer *buffer)
276{
277	struct sg_table *table;
278	int ret;
279
280	table = kzalloc(sizeof(struct sg_table), GFP_KERNEL);
281	if (!table)
282		return ERR_PTR(-ENOMEM);
283	ret = sg_alloc_table(table, 1, GFP_KERNEL);
284	if (ret) {
285		kfree(table);
286		return ERR_PTR(ret);
287	}
288	sg_set_page(table->sgl, virt_to_page(buffer->priv_virt), buffer->size,
289		    0);
290	return table;
291}
292
293void ion_system_contig_heap_unmap_dma(struct ion_heap *heap,
294				      struct ion_buffer *buffer)
295{
296	sg_free_table(buffer->sg_table);
297	kfree(buffer->sg_table);
298}
299
300int ion_system_contig_heap_map_user(struct ion_heap *heap,
301				    struct ion_buffer *buffer,
302				    struct vm_area_struct *vma)
303{
304	unsigned long pfn = __phys_to_pfn(virt_to_phys(buffer->priv_virt));
305	return remap_pfn_range(vma, vma->vm_start, pfn + vma->vm_pgoff,
306			       vma->vm_end - vma->vm_start,
307			       vma->vm_page_prot);
308
309}
310
311static struct ion_heap_ops kmalloc_ops = {
312	.allocate = ion_system_contig_heap_allocate,
313	.free = ion_system_contig_heap_free,
314	.phys = ion_system_contig_heap_phys,
315	.map_dma = ion_system_contig_heap_map_dma,
316	.unmap_dma = ion_system_contig_heap_unmap_dma,
317	.map_kernel = ion_system_heap_map_kernel,
318	.unmap_kernel = ion_system_heap_unmap_kernel,
319	.map_user = ion_system_contig_heap_map_user,
320};
321
322struct ion_heap *ion_system_contig_heap_create(struct ion_platform_heap *unused)
323{
324	struct ion_heap *heap;
325
326	heap = kzalloc(sizeof(struct ion_heap), GFP_KERNEL);
327	if (!heap)
328		return ERR_PTR(-ENOMEM);
329	heap->ops = &kmalloc_ops;
330	heap->type = ION_HEAP_TYPE_SYSTEM_CONTIG;
331	return heap;
332}
333
334void ion_system_contig_heap_destroy(struct ion_heap *heap)
335{
336	kfree(heap);
337}
338
339