drivers/staging/android/ion/ion_chunk_heap.c

   1 /*
   2  * drivers/staging/android/ion/ion_chunk_heap.c
   3  *
   4  * Copyright (C) 2012 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/dma-mapping.h>
  17 #include <linux/err.h>
  18 #include <linux/genalloc.h>
  19 #include <linux/io.h>
  20 #include <linux/mm.h>
  21 #include <linux/scatterlist.h>
  22 #include <linux/slab.h>
  23 #include <linux/vmalloc.h>
  24 #include "ion.h"
  25 #include "ion_priv.h"
  26
  27 struct ion_chunk_heap {
  28         struct ion_heap heap;
  29         struct gen_pool *pool;
  30         ion_phys_addr_t base;
  31         unsigned long chunk_size;
  32         unsigned long size;
  33         unsigned long allocated;
  34 };
  35
  36 static int ion_chunk_heap_allocate(struct ion_heap *heap,
  37                                       struct ion_buffer *buffer,
  38                                       unsigned long size, unsigned long align,
  39                                       unsigned long flags)
  40 {
  41         struct ion_chunk_heap *chunk_heap =
  42                 container_of(heap, struct ion_chunk_heap, heap);
  43         struct sg_table *table;
  44         struct scatterlist *sg;
  45         int ret, i;
  46         unsigned long num_chunks;
  47         unsigned long allocated_size;
  48
  49         if (align > chunk_heap->chunk_size)
  50                 return -EINVAL;
  51
  52         allocated_size = ALIGN(size, chunk_heap->chunk_size);
  53         num_chunks = allocated_size / chunk_heap->chunk_size;
  54
  55         if (allocated_size > chunk_heap->size - chunk_heap->allocated)
  56                 return -ENOMEM;
  57
  58         table = kmalloc(sizeof(*table), GFP_KERNEL);
  59         if (!table)
  60                 return -ENOMEM;
  61         ret = sg_alloc_table(table, num_chunks, GFP_KERNEL);
  62         if (ret) {
  63                 kfree(table);
  64                 return ret;
  65         }
  66
  67         sg = table->sgl;
  68         for (i = 0; i < num_chunks; i++) {
  69                 unsigned long paddr = gen_pool_alloc(chunk_heap->pool,
  70                                                      chunk_heap->chunk_size);
  71                 if (!paddr)
  72                         goto err;
  73                 sg_set_page(sg, pfn_to_page(PFN_DOWN(paddr)),
  74                                 chunk_heap->chunk_size, 0);
  75                 sg = sg_next(sg);
  76         }
  77
  78         buffer->sg_table = table;
  79         chunk_heap->allocated += allocated_size;
  80         return 0;
  81 err:
  82         sg = table->sgl;
  83         for (i -= 1; i >= 0; i--) {
  84                 gen_pool_free(chunk_heap->pool, page_to_phys(sg_page(sg)),
  85                               sg->length);
  86                 sg = sg_next(sg);
  87         }
  88         sg_free_table(table);
  89         kfree(table);
  90         return -ENOMEM;
  91 }
  92
  93 static void ion_chunk_heap_free(struct ion_buffer *buffer)
  94 {
  95         struct ion_heap *heap = buffer->heap;
  96         struct ion_chunk_heap *chunk_heap =
  97                 container_of(heap, struct ion_chunk_heap, heap);
  98         struct sg_table *table = buffer->sg_table;
  99         struct scatterlist *sg;
 100         int i;
 101         unsigned long allocated_size;
 102
 103         allocated_size = ALIGN(buffer->size, chunk_heap->chunk_size);
 104
 105         ion_heap_buffer_zero(buffer);
 106
 107         if (ion_buffer_cached(buffer))
 108                 dma_sync_sg_for_device(NULL, table->sgl, table->nents,
 109                                                         DMA_BIDIRECTIONAL);
 110
 111         for_each_sg(table->sgl, sg, table->nents, i) {
 112                 gen_pool_free(chunk_heap->pool, page_to_phys(sg_page(sg)),
 113                               sg->length);
 114         }
 115         chunk_heap->allocated -= allocated_size;
 116         sg_free_table(table);
 117         kfree(table);
 118 }
 119
 120 static struct ion_heap_ops chunk_heap_ops = {
 121         .allocate = ion_chunk_heap_allocate,
 122         .free = ion_chunk_heap_free,
 123         .map_user = ion_heap_map_user,
 124         .map_kernel = ion_heap_map_kernel,
 125         .unmap_kernel = ion_heap_unmap_kernel,
 126 };
 127
 128 struct ion_heap *ion_chunk_heap_create(struct ion_platform_heap *heap_data)
 129 {
 130         struct ion_chunk_heap *chunk_heap;
 131         int ret;
 132         struct page *page;
 133         size_t size;
 134
 135         page = pfn_to_page(PFN_DOWN(heap_data->base));
 136         size = heap_data->size;
 137
 138         ion_pages_sync_for_device(NULL, page, size, DMA_BIDIRECTIONAL);
 139
 140         ret = ion_heap_pages_zero(page, size, pgprot_writecombine(PAGE_KERNEL));
 141         if (ret)
 142                 return ERR_PTR(ret);
 143
 144         chunk_heap = kzalloc(sizeof(*chunk_heap), GFP_KERNEL);
 145         if (!chunk_heap)
 146                 return ERR_PTR(-ENOMEM);
 147
 148         chunk_heap->chunk_size = (unsigned long)heap_data->priv;
 149         chunk_heap->pool = gen_pool_create(get_order(chunk_heap->chunk_size) +
 150                                            PAGE_SHIFT, -1);
 151         if (!chunk_heap->pool) {
 152                 ret = -ENOMEM;
 153                 goto error_gen_pool_create;
 154         }
 155         chunk_heap->base = heap_data->base;
 156         chunk_heap->size = heap_data->size;
 157         chunk_heap->allocated = 0;
 158
 159         gen_pool_add(chunk_heap->pool, chunk_heap->base, heap_data->size, -1);
 160         chunk_heap->heap.ops = &chunk_heap_ops;
 161         chunk_heap->heap.type = ION_HEAP_TYPE_CHUNK;
 162         chunk_heap->heap.flags = ION_HEAP_FLAG_DEFER_FREE;
 163         pr_debug("%s: base %lu size %zu align %ld\n", __func__,
 164                 chunk_heap->base, heap_data->size, heap_data->align);
 165
 166         return &chunk_heap->heap;
 167
 168 error_gen_pool_create:
 169         kfree(chunk_heap);
 170         return ERR_PTR(ret);
 171 }
 172
 173 void ion_chunk_heap_destroy(struct ion_heap *heap)
 174 {
 175         struct ion_chunk_heap *chunk_heap =
 176              container_of(heap, struct  ion_chunk_heap, heap);
 177
 178         gen_pool_destroy(chunk_heap->pool);
 179         kfree(chunk_heap);
 180         chunk_heap = NULL;
 181 }