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         info = kzalloc(sizeof(struct ion_cma_buffer_info), GFP_KERNEL);
  73         if (!info) {
  74                 dev_err(dev, "Can't allocate buffer info\n");
  75                 return ION_CMA_ALLOCATE_FAILED;
  76         }
  77
  78         info->cpu_addr = dma_alloc_coherent(dev, len, &(info->handle), 0);
  79
  80         if (!info->cpu_addr) {
  81                 dev_err(dev, "Fail to allocate buffer\n");
  82                 goto err;
  83         }
  84
  85         info->table = kmalloc(sizeof(struct sg_table), GFP_KERNEL);
  86         if (!info->table) {
  87                 dev_err(dev, "Fail to allocate sg table\n");
  88                 goto free_mem;
  89         }
  90
  91         if (ion_cma_get_sgtable
  92             (dev, info->table, info->cpu_addr, info->handle, len))
  93                 goto free_table;
  94         /* keep this for memory release */
  95         buffer->priv_virt = info;
  96         dev_dbg(dev, "Allocate buffer %p\n", buffer);
  97         return 0;
  98
  99 free_table:
 100         kfree(info->table);
 101 free_mem:
 102         dma_free_coherent(dev, len, info->cpu_addr, info->handle);
 103 err:
 104         kfree(info);
 105         return ION_CMA_ALLOCATE_FAILED;
 106 }
 107
 108 static void ion_cma_free(struct ion_buffer *buffer)
 109 {
 110         struct ion_cma_heap *cma_heap = to_cma_heap(buffer->heap);
 111         struct device *dev = cma_heap->dev;
 112         struct ion_cma_buffer_info *info = buffer->priv_virt;
 113
 114         dev_dbg(dev, "Release buffer %p\n", buffer);
 115         /* release memory */
 116         dma_free_coherent(dev, buffer->size, info->cpu_addr, info->handle);
 117         /* release sg table */
 118         sg_free_table(info->table);
 119         kfree(info->table);
 120         kfree(info);
 121 }
 122
 123 /* return physical address in addr */
 124 static int ion_cma_phys(struct ion_heap *heap, struct ion_buffer *buffer,
 125                         ion_phys_addr_t *addr, size_t *len)
 126 {
 127         struct ion_cma_heap *cma_heap = to_cma_heap(buffer->heap);
 128         struct device *dev = cma_heap->dev;
 129         struct ion_cma_buffer_info *info = buffer->priv_virt;
 130
 131         dev_dbg(dev, "Return buffer %p physical address 0x%pa\n", buffer,
 132                 &info->handle);
 133
 134         *addr = info->handle;
 135         *len = buffer->size;
 136
 137         return 0;
 138 }
 139
 140 static struct sg_table *ion_cma_heap_map_dma(struct ion_heap *heap,
 141                                              struct ion_buffer *buffer)
 142 {
 143         struct ion_cma_buffer_info *info = buffer->priv_virt;
 144
 145         return info->table;
 146 }
 147
 148 static void ion_cma_heap_unmap_dma(struct ion_heap *heap,
 149                                    struct ion_buffer *buffer)
 150 {
 151         return;
 152 }
 153
 154 static int ion_cma_mmap(struct ion_heap *mapper, struct ion_buffer *buffer,
 155                         struct vm_area_struct *vma)
 156 {
 157         struct ion_cma_heap *cma_heap = to_cma_heap(buffer->heap);
 158         struct device *dev = cma_heap->dev;
 159         struct ion_cma_buffer_info *info = buffer->priv_virt;
 160
 161         return dma_mmap_coherent(dev, vma, info->cpu_addr, info->handle,
 162                                  buffer->size);
 163 }
 164
 165 static void *ion_cma_map_kernel(struct ion_heap *heap,
 166                                 struct ion_buffer *buffer)
 167 {
 168         struct ion_cma_buffer_info *info = buffer->priv_virt;
 169         /* kernel memory mapping has been done at allocation time */
 170         return info->cpu_addr;
 171 }
 172
 173 static struct ion_heap_ops ion_cma_ops = {
 174         .allocate = ion_cma_allocate,
 175         .free = ion_cma_free,
 176         .map_dma = ion_cma_heap_map_dma,
 177         .unmap_dma = ion_cma_heap_unmap_dma,
 178         .phys = ion_cma_phys,
 179         .map_user = ion_cma_mmap,
 180         .map_kernel = ion_cma_map_kernel,
 181 };
 182
 183 struct ion_heap *ion_cma_heap_create(struct ion_platform_heap *data)
 184 {
 185         struct ion_cma_heap *cma_heap;
 186
 187         cma_heap = kzalloc(sizeof(struct ion_cma_heap), GFP_KERNEL);
 188
 189         if (!cma_heap)
 190                 return ERR_PTR(-ENOMEM);
 191
 192         cma_heap->heap.ops = &ion_cma_ops;
 193         /* get device from private heaps data, later it will be
 194          * used to make the link with reserved CMA memory */
 195         cma_heap->dev = data->priv;
 196         cma_heap->heap.type = ION_HEAP_TYPE_DMA;
 197         return &cma_heap->heap;
 198 }
 199
 200 void ion_cma_heap_destroy(struct ion_heap *heap)
 201 {
 202         struct ion_cma_heap *cma_heap = to_cma_heap(heap);
 203
 204         kfree(cma_heap);
 205 }