Pileus Git - ~andy/linux/blob - drivers/staging/android/ion/ion_cma_heap.c

   1 /*
   2  * drivers/staging/android/ion/ion_cma_heap.c
   3  *
   4  * Copyright (C) Linaro 2012
   5  * Author: <benjamin.gaignard@linaro.org> for ST-Ericsson.
   6  *
   7  * This software is licensed under the terms of the GNU General Public
   8  * License version 2, as published by the Free Software Foundation, and
   9  * may be copied, distributed, and modified under those terms.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  */
  17
  18 #include <linux/device.h>
  19 #include <linux/slab.h>
  20 #include <linux/errno.h>
  21 #include <linux/err.h>
  22 #include <linux/dma-mapping.h>
  23
  24 #include "ion.h"
  25 #include "ion_priv.h"
  26
  27 #define ION_CMA_ALLOCATE_FAILED -1
  28
  29 struct ion_cma_heap {
  30         struct ion_heap heap;
  31         struct device *dev;
  32 };
  33
  34 #define to_cma_heap(x) container_of(x, struct ion_cma_heap, heap)
  35
  36 struct ion_cma_buffer_info {
  37         void *cpu_addr;
  38         dma_addr_t handle;
  39         struct sg_table *table;
  40 };
  41
  42 /*
  43  * Create scatter-list for the already allocated DMA buffer.
  44  * This function could be replaced by dma_common_get_sgtable
  45  * as soon as it will avalaible.
  46  */
  47 static int ion_cma_get_sgtable(struct device *dev, struct sg_table *sgt,
  48                                void *cpu_addr, dma_addr_t handle, size_t size)
  49 {
  50         struct page *page = virt_to_page(cpu_addr);
  51         int ret;
  52
  53         ret = sg_alloc_table(sgt, 1, GFP_KERNEL);
  54         if (unlikely(ret))
  55                 return ret;
  56
  57         sg_set_page(sgt->sgl, page, PAGE_ALIGN(size), 0);
  58         return 0;
  59 }
  60
  61 /* ION CMA heap operations functions */
  62 static int ion_cma_allocate(struct ion_heap *heap, struct ion_buffer *buffer,
  63                             unsigned long len, unsigned long align,
  64                             unsigned long flags)
  65 {
  66         struct ion_cma_heap *cma_heap = to_cma_heap(heap);
  67         struct device *dev = cma_heap->dev;
  68         struct ion_cma_buffer_info *info;
  69
  70         dev_dbg(dev, "Request buffer allocation len %ld\n", len);
  71
  72         if (buffer->flags & ION_FLAG_CACHED)
  73                 return -EINVAL;
  74
  75         if (align > PAGE_SIZE)
  76                 return -EINVAL;
  77
  78         info = kzalloc(sizeof(struct ion_cma_buffer_info), GFP_KERNEL);
  79         if (!info) {
  80                 dev_err(dev, "Can't allocate buffer info\n");
  81                 return ION_CMA_ALLOCATE_FAILED;
  82         }
  83
  84         info->cpu_addr = dma_alloc_coherent(dev, len, &(info->handle),
  85                                                 GFP_HIGHUSER | __GFP_ZERO);
  86
  87         if (!info->cpu_addr) {
  88                 dev_err(dev, "Fail to allocate buffer\n");
  89                 goto err;
  90         }
  91
  92         info->table = kmalloc(sizeof(struct sg_table), GFP_KERNEL);
  93         if (!info->table) {
  94                 dev_err(dev, "Fail to allocate sg table\n");
  95                 goto free_mem;
  96         }
  97
  98         if (ion_cma_get_sgtable
  99             (dev, info->table, info->cpu_addr, info->handle, len))
 100                 goto free_table;
 101         /* keep this for memory release */
 102         buffer->priv_virt = info;
 103         dev_dbg(dev, "Allocate buffer %p\n", buffer);
 104         return 0;
 105
 106 free_table:
 107         kfree(info->table);
 108 free_mem:
 109         dma_free_coherent(dev, len, info->cpu_addr, info->handle);
 110 err:
 111         kfree(info);
 112         return ION_CMA_ALLOCATE_FAILED;
 113 }
 114
 115 static void ion_cma_free(struct ion_buffer *buffer)
 116 {
 117         struct ion_cma_heap *cma_heap = to_cma_heap(buffer->heap);
 118         struct device *dev = cma_heap->dev;
 119         struct ion_cma_buffer_info *info = buffer->priv_virt;
 120
 121         dev_dbg(dev, "Release buffer %p\n", buffer);
 122         /* release memory */
 123         dma_free_coherent(dev, buffer->size, info->cpu_addr, info->handle);
 124         /* release sg table */
 125         sg_free_table(info->table);
 126         kfree(info->table);
 127         kfree(info);
 128 }
 129
 130 /* return physical address in addr */
 131 static int ion_cma_phys(struct ion_heap *heap, struct ion_buffer *buffer,
 132                         ion_phys_addr_t *addr, size_t *len)
 133 {
 134         struct ion_cma_heap *cma_heap = to_cma_heap(buffer->heap);
 135         struct device *dev = cma_heap->dev;
 136         struct ion_cma_buffer_info *info = buffer->priv_virt;
 137
 138         dev_dbg(dev, "Return buffer %p physical address 0x%pa\n", buffer,
 139                 &info->handle);
 140
 141         *addr = info->handle;
 142         *len = buffer->size;
 143
 144         return 0;
 145 }
 146
 147 static struct sg_table *ion_cma_heap_map_dma(struct ion_heap *heap,
 148                                              struct ion_buffer *buffer)
 149 {
 150         struct ion_cma_buffer_info *info = buffer->priv_virt;
 151
 152         return info->table;
 153 }
 154
 155 static void ion_cma_heap_unmap_dma(struct ion_heap *heap,
 156                                    struct ion_buffer *buffer)
 157 {
 158         return;
 159 }
 160
 161 static int ion_cma_mmap(struct ion_heap *mapper, struct ion_buffer *buffer,
 162                         struct vm_area_struct *vma)
 163 {
 164         struct ion_cma_heap *cma_heap = to_cma_heap(buffer->heap);
 165         struct device *dev = cma_heap->dev;
 166         struct ion_cma_buffer_info *info = buffer->priv_virt;
 167
 168         return dma_mmap_coherent(dev, vma, info->cpu_addr, info->handle,
 169                                  buffer->size);
 170 }
 171
 172 static void *ion_cma_map_kernel(struct ion_heap *heap,
 173                                 struct ion_buffer *buffer)
 174 {
 175         struct ion_cma_buffer_info *info = buffer->priv_virt;
 176         /* kernel memory mapping has been done at allocation time */
 177         return info->cpu_addr;
 178 }
 179
 180 static void ion_cma_unmap_kernel(struct ion_heap *heap,
 181                                         struct ion_buffer *buffer)
 182 {
 183 }
 184
 185 static struct ion_heap_ops ion_cma_ops = {
 186         .allocate = ion_cma_allocate,
 187         .free = ion_cma_free,
 188         .map_dma = ion_cma_heap_map_dma,
 189         .unmap_dma = ion_cma_heap_unmap_dma,
 190         .phys = ion_cma_phys,
 191         .map_user = ion_cma_mmap,
 192         .map_kernel = ion_cma_map_kernel,
 193         .unmap_kernel = ion_cma_unmap_kernel,
 194 };
 195
 196 struct ion_heap *ion_cma_heap_create(struct ion_platform_heap *data)
 197 {
 198         struct ion_cma_heap *cma_heap;
 199
 200         cma_heap = kzalloc(sizeof(struct ion_cma_heap), GFP_KERNEL);
 201
 202         if (!cma_heap)
 203                 return ERR_PTR(-ENOMEM);
 204
 205         cma_heap->heap.ops = &ion_cma_ops;
 206         /* get device from private heaps data, later it will be
 207          * used to make the link with reserved CMA memory */
 208         cma_heap->dev = data->priv;
 209         cma_heap->heap.type = ION_HEAP_TYPE_DMA;
 210         return &cma_heap->heap;
 211 }
 212
 213 void ion_cma_heap_destroy(struct ion_heap *heap)
 214 {
 215         struct ion_cma_heap *cma_heap = to_cma_heap(heap);
 216
 217         kfree(cma_heap);
 218 }