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 /* ION CMA heap operations functions */
  44 static int ion_cma_allocate(struct ion_heap *heap, struct ion_buffer *buffer,
  45                             unsigned long len, unsigned long align,
  46                             unsigned long flags)
  47 {
  48         struct ion_cma_heap *cma_heap = to_cma_heap(heap);
  49         struct device *dev = cma_heap->dev;
  50         struct ion_cma_buffer_info *info;
  51
  52         dev_dbg(dev, "Request buffer allocation len %ld\n", len);
  53
  54         if (buffer->flags & ION_FLAG_CACHED)
  55                 return -EINVAL;
  56
  57         if (align > PAGE_SIZE)
  58                 return -EINVAL;
  59
  60         info = kzalloc(sizeof(struct ion_cma_buffer_info), GFP_KERNEL);
  61         if (!info)
  62                 return ION_CMA_ALLOCATE_FAILED;
  63
  64         info->cpu_addr = dma_alloc_coherent(dev, len, &(info->handle),
  65                                                 GFP_HIGHUSER | __GFP_ZERO);
  66
  67         if (!info->cpu_addr) {
  68                 dev_err(dev, "Fail to allocate buffer\n");
  69                 goto err;
  70         }
  71
  72         info->table = kmalloc(sizeof(struct sg_table), GFP_KERNEL);
  73         if (!info->table)
  74                 goto free_mem;
  75
  76         if (dma_get_sgtable(dev, info->table, info->cpu_addr, info->handle,
  77                             len))
  78                 goto free_table;
  79         /* keep this for memory release */
  80         buffer->priv_virt = info;
  81         buffer->sg_table = info->table;
  82         dev_dbg(dev, "Allocate buffer %p\n", buffer);
  83         return 0;
  84
  85 free_table:
  86         kfree(info->table);
  87 free_mem:
  88         dma_free_coherent(dev, len, info->cpu_addr, info->handle);
  89 err:
  90         kfree(info);
  91         return ION_CMA_ALLOCATE_FAILED;
  92 }
  93
  94 static void ion_cma_free(struct ion_buffer *buffer)
  95 {
  96         struct ion_cma_heap *cma_heap = to_cma_heap(buffer->heap);
  97         struct device *dev = cma_heap->dev;
  98         struct ion_cma_buffer_info *info = buffer->priv_virt;
  99
 100         dev_dbg(dev, "Release buffer %p\n", buffer);
 101         /* release memory */
 102         dma_free_coherent(dev, buffer->size, info->cpu_addr, info->handle);
 103         /* release sg table */
 104         sg_free_table(info->table);
 105         kfree(info->table);
 106         kfree(info);
 107 }
 108
 109 static int ion_cma_mmap(struct ion_heap *mapper, struct ion_buffer *buffer,
 110                         struct vm_area_struct *vma)
 111 {
 112         struct ion_cma_heap *cma_heap = to_cma_heap(buffer->heap);
 113         struct device *dev = cma_heap->dev;
 114         struct ion_cma_buffer_info *info = buffer->priv_virt;
 115
 116         return dma_mmap_coherent(dev, vma, info->cpu_addr, info->handle,
 117                                  buffer->size);
 118 }
 119
 120 static void *ion_cma_map_kernel(struct ion_heap *heap,
 121                                 struct ion_buffer *buffer)
 122 {
 123         struct ion_cma_buffer_info *info = buffer->priv_virt;
 124         /* kernel memory mapping has been done at allocation time */
 125         return info->cpu_addr;
 126 }
 127
 128 static void ion_cma_unmap_kernel(struct ion_heap *heap,
 129                                  struct ion_buffer *buffer)
 130 {
 131 }
 132
 133 static struct ion_heap_ops ion_cma_ops = {
 134         .allocate = ion_cma_allocate,
 135         .free = ion_cma_free,
 136         .map_user = ion_cma_mmap,
 137         .map_kernel = ion_cma_map_kernel,
 138         .unmap_kernel = ion_cma_unmap_kernel,
 139 };
 140
 141 struct ion_heap *ion_cma_heap_create(struct ion_platform_heap *data)
 142 {
 143         struct ion_cma_heap *cma_heap;
 144
 145         cma_heap = kzalloc(sizeof(struct ion_cma_heap), GFP_KERNEL);
 146
 147         if (!cma_heap)
 148                 return ERR_PTR(-ENOMEM);
 149
 150         cma_heap->heap.ops = &ion_cma_ops;
 151         /*
 152          * get device from private heaps data, later it will be
 153          * used to make the link with reserved CMA memory
 154          */
 155         cma_heap->dev = data->priv;
 156         cma_heap->heap.type = ION_HEAP_TYPE_DMA;
 157         return &cma_heap->heap;
 158 }
 159
 160 void ion_cma_heap_destroy(struct ion_heap *heap)
 161 {
 162         struct ion_cma_heap *cma_heap = to_cma_heap(heap);
 163
 164         kfree(cma_heap);
 165 }