ion_chunk_heap.c revision ea89faff84e35c7a5b386f158b5aec0c6327441c
1/*
2 * drivers/staging/android/ion/ion_chunk_heap.c
3 *
4 * Copyright (C) 2012 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//#include <linux/spinlock.h>
17#include <linux/dma-mapping.h>
18#include <linux/err.h>
19#include <linux/genalloc.h>
20#include <linux/io.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
28#include <asm/mach/map.h>
29
30struct ion_chunk_heap {
31	struct ion_heap heap;
32	struct gen_pool *pool;
33	ion_phys_addr_t base;
34	unsigned long chunk_size;
35	unsigned long size;
36	unsigned long allocated;
37};
38
39static int ion_chunk_heap_allocate(struct ion_heap *heap,
40				      struct ion_buffer *buffer,
41				      unsigned long size, unsigned long align,
42				      unsigned long flags)
43{
44	struct ion_chunk_heap *chunk_heap =
45		container_of(heap, struct ion_chunk_heap, heap);
46	struct sg_table *table;
47	struct scatterlist *sg;
48	int ret, i;
49	unsigned long num_chunks;
50	unsigned long allocated_size;
51
52	if (ion_buffer_fault_user_mappings(buffer))
53		return -ENOMEM;
54
55	allocated_size = ALIGN(size, chunk_heap->chunk_size);
56	num_chunks = allocated_size / chunk_heap->chunk_size;
57
58	if (allocated_size > chunk_heap->size - chunk_heap->allocated)
59		return -ENOMEM;
60
61	table = kzalloc(sizeof(struct sg_table), GFP_KERNEL);
62	if (!table)
63		return -ENOMEM;
64	ret = sg_alloc_table(table, num_chunks, GFP_KERNEL);
65	if (ret) {
66		kfree(table);
67		return ret;
68	}
69
70	sg = table->sgl;
71	for (i = 0; i < num_chunks; i++) {
72		unsigned long paddr = gen_pool_alloc(chunk_heap->pool,
73						     chunk_heap->chunk_size);
74		if (!paddr)
75			goto err;
76		sg_set_page(sg, phys_to_page(paddr), chunk_heap->chunk_size, 0);
77		sg = sg_next(sg);
78	}
79
80	buffer->priv_virt = table;
81	chunk_heap->allocated += allocated_size;
82	return 0;
83err:
84	sg = table->sgl;
85	for (i -= 1; i >= 0; i--) {
86		gen_pool_free(chunk_heap->pool, page_to_phys(sg_page(sg)),
87			      sg_dma_len(sg));
88		sg = sg_next(sg);
89	}
90	sg_free_table(table);
91	kfree(table);
92	return -ENOMEM;
93}
94
95static void ion_chunk_heap_free(struct ion_buffer *buffer)
96{
97	struct ion_heap *heap = buffer->heap;
98	struct ion_chunk_heap *chunk_heap =
99		container_of(heap, struct ion_chunk_heap, heap);
100	struct sg_table *table = buffer->priv_virt;
101	struct scatterlist *sg;
102	int i;
103	unsigned long allocated_size;
104
105	allocated_size = ALIGN(buffer->size, chunk_heap->chunk_size);
106
107	ion_heap_buffer_zero(buffer);
108
109	for_each_sg(table->sgl, sg, table->nents, i) {
110		if (ion_buffer_cached(buffer))
111			arm_dma_ops.sync_single_for_device(NULL,
112				pfn_to_dma(NULL, page_to_pfn(sg_page(sg))),
113				sg_dma_len(sg), DMA_BIDIRECTIONAL);
114		gen_pool_free(chunk_heap->pool, page_to_phys(sg_page(sg)),
115			      sg_dma_len(sg));
116	}
117	chunk_heap->allocated -= allocated_size;
118	sg_free_table(table);
119	kfree(table);
120}
121
122struct sg_table *ion_chunk_heap_map_dma(struct ion_heap *heap,
123					 struct ion_buffer *buffer)
124{
125	return buffer->priv_virt;
126}
127
128void ion_chunk_heap_unmap_dma(struct ion_heap *heap,
129			       struct ion_buffer *buffer)
130{
131	return;
132}
133
134static struct ion_heap_ops chunk_heap_ops = {
135	.allocate = ion_chunk_heap_allocate,
136	.free = ion_chunk_heap_free,
137	.map_dma = ion_chunk_heap_map_dma,
138	.unmap_dma = ion_chunk_heap_unmap_dma,
139	.map_user = ion_heap_map_user,
140	.map_kernel = ion_heap_map_kernel,
141	.unmap_kernel = ion_heap_unmap_kernel,
142};
143
144struct ion_heap *ion_chunk_heap_create(struct ion_platform_heap *heap_data)
145{
146	struct ion_chunk_heap *chunk_heap;
147	struct vm_struct *vm_struct;
148	pgprot_t pgprot = pgprot_writecombine(PAGE_KERNEL);
149	int i, ret;
150
151
152	chunk_heap = kzalloc(sizeof(struct ion_chunk_heap), GFP_KERNEL);
153	if (!chunk_heap)
154		return ERR_PTR(-ENOMEM);
155
156	chunk_heap->chunk_size = (unsigned long)heap_data->priv;
157	chunk_heap->pool = gen_pool_create(get_order(chunk_heap->chunk_size) +
158					   PAGE_SHIFT, -1);
159	if (!chunk_heap->pool) {
160		ret = -ENOMEM;
161		goto error_gen_pool_create;
162	}
163	chunk_heap->base = heap_data->base;
164	chunk_heap->size = heap_data->size;
165	chunk_heap->allocated = 0;
166
167	vm_struct = get_vm_area(PAGE_SIZE, VM_ALLOC);
168	if (!vm_struct) {
169		ret = -ENOMEM;
170		goto error;
171	}
172	for (i = 0; i < chunk_heap->size; i += PAGE_SIZE) {
173		struct page *page = phys_to_page(chunk_heap->base + i);
174		struct page **pages = &page;
175
176		ret = map_vm_area(vm_struct, pgprot, &pages);
177		if (ret)
178			goto error_map_vm_area;
179		memset(vm_struct->addr, 0, PAGE_SIZE);
180		unmap_kernel_range((unsigned long)vm_struct->addr, PAGE_SIZE);
181	}
182	free_vm_area(vm_struct);
183
184	arm_dma_ops.sync_single_for_device(NULL,
185		pfn_to_dma(NULL, page_to_pfn(phys_to_page(heap_data->base))),
186		heap_data->size, DMA_BIDIRECTIONAL);
187	gen_pool_add(chunk_heap->pool, chunk_heap->base, heap_data->size, -1);
188	chunk_heap->heap.ops = &chunk_heap_ops;
189	chunk_heap->heap.type = ION_HEAP_TYPE_CHUNK;
190	chunk_heap->heap.flags = ION_HEAP_FLAG_DEFER_FREE;
191	pr_info("%s: base %lu size %u align %ld\n", __func__, chunk_heap->base,
192		heap_data->size, heap_data->align);
193
194	return &chunk_heap->heap;
195
196error_map_vm_area:
197	free_vm_area(vm_struct);
198error:
199	gen_pool_destroy(chunk_heap->pool);
200error_gen_pool_create:
201	kfree(chunk_heap);
202	return ERR_PTR(ret);
203}
204
205void ion_chunk_heap_destroy(struct ion_heap *heap)
206{
207	struct ion_chunk_heap *chunk_heap =
208	     container_of(heap, struct  ion_chunk_heap, heap);
209
210	gen_pool_destroy(chunk_heap->pool);
211	kfree(chunk_heap);
212	chunk_heap = NULL;
213}
214