ion_carveout_heap.c revision 8be3759a5e4ed91ffbe24d98b33a71f651cb3f9b 
1/*
2 * drivers/staging/android/ion/ion_carveout_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#include <linux/spinlock.h>
17
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
28struct ion_carveout_heap {
29	struct ion_heap heap;
30	struct gen_pool *pool;
31	ion_phys_addr_t base;
32};
33
34ion_phys_addr_t ion_carveout_allocate(struct ion_heap *heap,
35				      unsigned long size,
36				      unsigned long align)
37{
38	struct ion_carveout_heap *carveout_heap =
39		container_of(heap, struct ion_carveout_heap, heap);
40	unsigned long offset = gen_pool_alloc(carveout_heap->pool, size);
41
42	if (!offset)
43		return ION_CARVEOUT_ALLOCATE_FAIL;
44
45	return offset;
46}
47
48void ion_carveout_free(struct ion_heap *heap, ion_phys_addr_t addr,
49		       unsigned long size)
50{
51	struct ion_carveout_heap *carveout_heap =
52		container_of(heap, struct ion_carveout_heap, heap);
53
54	if (addr == ION_CARVEOUT_ALLOCATE_FAIL)
55		return;
56	gen_pool_free(carveout_heap->pool, addr, size);
57}
58
59static int ion_carveout_heap_phys(struct ion_heap *heap,
60				  struct ion_buffer *buffer,
61				  ion_phys_addr_t *addr, size_t *len)
62{
63	*addr = buffer->priv_phys;
64	*len = buffer->size;
65	return 0;
66}
67
68static int ion_carveout_heap_allocate(struct ion_heap *heap,
69				      struct ion_buffer *buffer,
70				      unsigned long size, unsigned long align,
71				      unsigned long flags)
72{
73	buffer->priv_phys = ion_carveout_allocate(heap, size, align);
74	return buffer->priv_phys == ION_CARVEOUT_ALLOCATE_FAIL ? -ENOMEM : 0;
75}
76
77static void ion_carveout_heap_free(struct ion_buffer *buffer)
78{
79	struct ion_heap *heap = buffer->heap;
80
81	ion_carveout_free(heap, buffer->priv_phys, buffer->size);
82	buffer->priv_phys = ION_CARVEOUT_ALLOCATE_FAIL;
83}
84
85struct sg_table *ion_carveout_heap_map_dma(struct ion_heap *heap,
86					      struct ion_buffer *buffer)
87{
88	struct sg_table *table;
89	int ret;
90
91	table = kzalloc(sizeof(struct sg_table), GFP_KERNEL);
92	if (!table)
93		return ERR_PTR(-ENOMEM);
94	ret = sg_alloc_table(table, 1, GFP_KERNEL);
95	if (ret) {
96		kfree(table);
97		return ERR_PTR(ret);
98	}
99	sg_set_page(table->sgl, phys_to_page(buffer->priv_phys), buffer->size,
100		    0);
101	return table;
102}
103
104void ion_carveout_heap_unmap_dma(struct ion_heap *heap,
105				 struct ion_buffer *buffer)
106{
107	sg_free_table(buffer->sg_table);
108}
109
110static struct ion_heap_ops carveout_heap_ops = {
111	.allocate = ion_carveout_heap_allocate,
112	.free = ion_carveout_heap_free,
113	.phys = ion_carveout_heap_phys,
114	.map_dma = ion_carveout_heap_map_dma,
115	.unmap_dma = ion_carveout_heap_unmap_dma,
116	.map_user = ion_heap_map_user,
117	.map_kernel = ion_heap_map_kernel,
118	.unmap_kernel = ion_heap_unmap_kernel,
119};
120
121struct ion_heap *ion_carveout_heap_create(struct ion_platform_heap *heap_data)
122{
123	struct ion_carveout_heap *carveout_heap;
124
125	carveout_heap = kzalloc(sizeof(struct ion_carveout_heap), GFP_KERNEL);
126	if (!carveout_heap)
127		return ERR_PTR(-ENOMEM);
128
129	carveout_heap->pool = gen_pool_create(12, -1);
130	if (!carveout_heap->pool) {
131		kfree(carveout_heap);
132		return ERR_PTR(-ENOMEM);
133	}
134	carveout_heap->base = heap_data->base;
135	gen_pool_add(carveout_heap->pool, carveout_heap->base, heap_data->size,
136		     -1);
137	carveout_heap->heap.ops = &carveout_heap_ops;
138	carveout_heap->heap.type = ION_HEAP_TYPE_CARVEOUT;
139
140	return &carveout_heap->heap;
141}
142
143void ion_carveout_heap_destroy(struct ion_heap *heap)
144{
145	struct ion_carveout_heap *carveout_heap =
146	     container_of(heap, struct  ion_carveout_heap, heap);
147
148	gen_pool_destroy(carveout_heap->pool);
149	kfree(carveout_heap);
150	carveout_heap = NULL;
151}
152