ion_heap.c revision 0b6b2cde0928707a618ce8c07970219f21d066e5 
1/*
2 * drivers/staging/android/ion/ion_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 <linux/err.h>
18#include <linux/mm.h>
19#include <linux/scatterlist.h>
20#include <linux/vmalloc.h>
21#include "ion.h"
22#include "ion_priv.h"
23
24void *ion_heap_map_kernel(struct ion_heap *heap,
25			  struct ion_buffer *buffer)
26{
27	struct scatterlist *sg;
28	int i, j;
29	void *vaddr;
30	pgprot_t pgprot;
31	struct sg_table *table = buffer->sg_table;
32	int npages = PAGE_ALIGN(buffer->size) / PAGE_SIZE;
33	struct page **pages = vmalloc(sizeof(struct page *) * npages);
34	struct page **tmp = pages;
35
36	if (!pages)
37		return 0;
38
39	if (buffer->flags & ION_FLAG_CACHED)
40		pgprot = PAGE_KERNEL;
41	else
42		pgprot = pgprot_writecombine(PAGE_KERNEL);
43
44	for_each_sg(table->sgl, sg, table->nents, i) {
45		int npages_this_entry = PAGE_ALIGN(sg_dma_len(sg)) / PAGE_SIZE;
46		struct page *page = sg_page(sg);
47		BUG_ON(i >= npages);
48		for (j = 0; j < npages_this_entry; j++) {
49			*(tmp++) = page++;
50		}
51	}
52	vaddr = vmap(pages, npages, VM_MAP, pgprot);
53	vfree(pages);
54
55	return vaddr;
56}
57
58void ion_heap_unmap_kernel(struct ion_heap *heap,
59			   struct ion_buffer *buffer)
60{
61	vunmap(buffer->vaddr);
62}
63
64int ion_heap_map_user(struct ion_heap *heap, struct ion_buffer *buffer,
65		      struct vm_area_struct *vma)
66{
67	struct sg_table *table = buffer->sg_table;
68	unsigned long addr = vma->vm_start;
69	unsigned long offset = vma->vm_pgoff * PAGE_SIZE;
70	struct scatterlist *sg;
71	int i;
72
73	for_each_sg(table->sgl, sg, table->nents, i) {
74		struct page *page = sg_page(sg);
75		unsigned long remainder = vma->vm_end - addr;
76		unsigned long len = sg_dma_len(sg);
77
78		if (offset >= sg_dma_len(sg)) {
79			offset -= sg_dma_len(sg);
80			continue;
81		} else if (offset) {
82			page += offset / PAGE_SIZE;
83			len = sg_dma_len(sg) - offset;
84			offset = 0;
85		}
86		len = min(len, remainder);
87		remap_pfn_range(vma, addr, page_to_pfn(page), len,
88				vma->vm_page_prot);
89		addr += len;
90		if (addr >= vma->vm_end)
91			return 0;
92	}
93	return 0;
94}
95
96int ion_heap_buffer_zero(struct ion_buffer *buffer)
97{
98	struct sg_table *table = buffer->sg_table;
99	pgprot_t pgprot;
100	struct scatterlist *sg;
101	struct vm_struct *vm_struct;
102	int i, j, ret = 0;
103
104	if (buffer->flags & ION_FLAG_CACHED)
105		pgprot = PAGE_KERNEL;
106	else
107		pgprot = pgprot_writecombine(PAGE_KERNEL);
108
109	vm_struct = get_vm_area(PAGE_SIZE, VM_ALLOC);
110	if (!vm_struct)
111		return -ENOMEM;
112
113	for_each_sg(table->sgl, sg, table->nents, i) {
114		struct page *page = sg_page(sg);
115		unsigned long len = sg_dma_len(sg);
116
117		for (j = 0; j < len / PAGE_SIZE; j++) {
118			struct page *sub_page = page + j;
119			struct page **pages = &sub_page;
120			ret = map_vm_area(vm_struct, pgprot, &pages);
121			if (ret)
122				goto end;
123			memset(vm_struct->addr, 0, PAGE_SIZE);
124			unmap_kernel_range((unsigned long)vm_struct->addr,
125					   PAGE_SIZE);
126		}
127	}
128end:
129	free_vm_area(vm_struct);
130	return ret;
131}
132
133struct ion_heap *ion_heap_create(struct ion_platform_heap *heap_data)
134{
135	struct ion_heap *heap = NULL;
136
137	switch (heap_data->type) {
138	case ION_HEAP_TYPE_SYSTEM_CONTIG:
139		heap = ion_system_contig_heap_create(heap_data);
140		break;
141	case ION_HEAP_TYPE_SYSTEM:
142		heap = ion_system_heap_create(heap_data);
143		break;
144	case ION_HEAP_TYPE_CARVEOUT:
145		heap = ion_carveout_heap_create(heap_data);
146		break;
147	case ION_HEAP_TYPE_CHUNK:
148		heap = ion_chunk_heap_create(heap_data);
149		break;
150	default:
151		pr_err("%s: Invalid heap type %d\n", __func__,
152		       heap_data->type);
153		return ERR_PTR(-EINVAL);
154	}
155
156	if (IS_ERR_OR_NULL(heap)) {
157		pr_err("%s: error creating heap %s type %d base %lu size %u\n",
158		       __func__, heap_data->name, heap_data->type,
159		       heap_data->base, heap_data->size);
160		return ERR_PTR(-EINVAL);
161	}
162
163	heap->name = heap_data->name;
164	heap->id = heap_data->id;
165	return heap;
166}
167
168void ion_heap_destroy(struct ion_heap *heap)
169{
170	if (!heap)
171		return;
172
173	switch (heap->type) {
174	case ION_HEAP_TYPE_SYSTEM_CONTIG:
175		ion_system_contig_heap_destroy(heap);
176		break;
177	case ION_HEAP_TYPE_SYSTEM:
178		ion_system_heap_destroy(heap);
179		break;
180	case ION_HEAP_TYPE_CARVEOUT:
181		ion_carveout_heap_destroy(heap);
182		break;
183	case ION_HEAP_TYPE_CHUNK:
184		ion_chunk_heap_destroy(heap);
185		break;
186	default:
187		pr_err("%s: Invalid heap type %d\n", __func__,
188		       heap->type);
189	}
190}
191