kernel/drivers/staging/android/ion/ion_carveout_heap.c

   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 #include <linux/dma-mapping.h>
  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
  28 struct ion_carveout_heap {
  29         struct ion_heap heap;
  30         struct gen_pool *pool;
  31         ion_phys_addr_t base;
  32 };
  33
  34 ion_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
  48 void 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
  59 static 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         struct sg_table *table = buffer->priv_virt;
  64         struct page *page = sg_page(table->sgl);
  65         ion_phys_addr_t paddr = PFN_PHYS(page_to_pfn(page));
  66
  67         *addr = paddr;
  68         *len = buffer->size;
  69         return 0;
  70 }
  71
  72 static int ion_carveout_heap_allocate(struct ion_heap *heap,
  73                                       struct ion_buffer *buffer,
  74                                       unsigned long size, unsigned long align,
  75                                       unsigned long flags)
  76 {
  77         struct sg_table *table;
  78         ion_phys_addr_t paddr;
  79         int ret;
  80
  81         if (align > PAGE_SIZE)
  82                 return -EINVAL;
  83
  84         table = kmalloc(sizeof(struct sg_table), GFP_KERNEL);
  85         if (!table)
  86                 return -ENOMEM;
  87         ret = sg_alloc_table(table, 1, GFP_KERNEL);
  88         if (ret)
  89                 goto err_free;
  90
  91         paddr = ion_carveout_allocate(heap, size, align);
  92         if (paddr == ION_CARVEOUT_ALLOCATE_FAIL) {
  93                 ret = -ENOMEM;
  94                 goto err_free_table;
  95         }
  96
  97         sg_set_page(table->sgl, pfn_to_page(PFN_DOWN(paddr)), size, 0);
  98         buffer->priv_virt = table;
  99
 100         return 0;
 101
 102 err_free_table:
 103         sg_free_table(table);
 104 err_free:
 105         kfree(table);
 106         return ret;
 107 }
 108
 109 static void ion_carveout_heap_free(struct ion_buffer *buffer)
 110 {
 111         struct ion_heap *heap = buffer->heap;
 112         struct sg_table *table = buffer->priv_virt;
 113         struct page *page = sg_page(table->sgl);
 114         ion_phys_addr_t paddr = PFN_PHYS(page_to_pfn(page));
 115
 116         ion_heap_buffer_zero(buffer);
 117
 118         if (ion_buffer_cached(buffer))
 119                 dma_sync_sg_for_device(NULL, table->sgl, table->nents,
 120                                                         DMA_BIDIRECTIONAL);
 121
 122         ion_carveout_free(heap, paddr, buffer->size);
 123         sg_free_table(table);
 124         kfree(table);
 125 }
 126
 127 static struct sg_table *ion_carveout_heap_map_dma(struct ion_heap *heap,
 128                                                   struct ion_buffer *buffer)
 129 {
 130         return buffer->priv_virt;
 131 }
 132
 133 static void ion_carveout_heap_unmap_dma(struct ion_heap *heap,
 134                                         struct ion_buffer *buffer)
 135 {
 136 }
 137
 138 static struct ion_heap_ops carveout_heap_ops = {
 139         .allocate = ion_carveout_heap_allocate,
 140         .free = ion_carveout_heap_free,
 141         .phys = ion_carveout_heap_phys,
 142         .map_dma = ion_carveout_heap_map_dma,
 143         .unmap_dma = ion_carveout_heap_unmap_dma,
 144         .map_user = ion_heap_map_user,
 145         .map_kernel = ion_heap_map_kernel,
 146         .unmap_kernel = ion_heap_unmap_kernel,
 147 };
 148
 149 struct ion_heap *ion_carveout_heap_create(struct ion_platform_heap *heap_data)
 150 {
 151         struct ion_carveout_heap *carveout_heap;
 152         int ret;
 153
 154         struct page *page;
 155         size_t size;
 156
 157         page = pfn_to_page(PFN_DOWN(heap_data->base));
 158         size = heap_data->size;
 159
 160         ion_pages_sync_for_device(NULL, page, size, DMA_BIDIRECTIONAL);
 161
 162         ret = ion_heap_pages_zero(page, size, pgprot_writecombine(PAGE_KERNEL));
 163         if (ret)
 164                 return ERR_PTR(ret);
 165
 166         carveout_heap = kzalloc(sizeof(struct ion_carveout_heap), GFP_KERNEL);
 167         if (!carveout_heap)
 168                 return ERR_PTR(-ENOMEM);
 169
 170         carveout_heap->pool = gen_pool_create(12, -1);
 171         if (!carveout_heap->pool) {
 172                 kfree(carveout_heap);
 173                 return ERR_PTR(-ENOMEM);
 174         }
 175         carveout_heap->base = heap_data->base;
 176         gen_pool_add(carveout_heap->pool, carveout_heap->base, heap_data->size,
 177                      -1);
 178         carveout_heap->heap.ops = &carveout_heap_ops;
 179         carveout_heap->heap.type = ION_HEAP_TYPE_CARVEOUT;
 180         carveout_heap->heap.flags = ION_HEAP_FLAG_DEFER_FREE;
 181
 182         return &carveout_heap->heap;
 183 }
 184
 185 void ion_carveout_heap_destroy(struct ion_heap *heap)
 186 {
 187         struct ion_carveout_heap *carveout_heap =
 188              container_of(heap, struct  ion_carveout_heap, heap);
 189
 190         gen_pool_destroy(carveout_heap->pool);
 191         kfree(carveout_heap);
 192         carveout_heap = NULL;
 193 }