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 #define ION_CARVEOUT_ALLOCATE_FAIL      -1
  29
  30 struct ion_carveout_heap {
  31         struct ion_heap heap;
  32         struct gen_pool *pool;
  33         ion_phys_addr_t base;
  34 };
  35
  36 static ion_phys_addr_t ion_carveout_allocate(struct ion_heap *heap,
  37                                              unsigned long size,
  38                                              unsigned long align)
  39 {
  40         struct ion_carveout_heap *carveout_heap =
  41                 container_of(heap, struct ion_carveout_heap, heap);
  42         unsigned long offset = gen_pool_alloc(carveout_heap->pool, size);
  43
  44         if (!offset)
  45                 return ION_CARVEOUT_ALLOCATE_FAIL;
  46
  47         return offset;
  48 }
  49
  50 static void ion_carveout_free(struct ion_heap *heap, ion_phys_addr_t addr,
  51                               unsigned long size)
  52 {
  53         struct ion_carveout_heap *carveout_heap =
  54                 container_of(heap, struct ion_carveout_heap, heap);
  55
  56         if (addr == ION_CARVEOUT_ALLOCATE_FAIL)
  57                 return;
  58         gen_pool_free(carveout_heap->pool, addr, size);
  59 }
  60
  61 static int ion_carveout_heap_allocate(struct ion_heap *heap,
  62                                       struct ion_buffer *buffer,
  63                                       unsigned long size, unsigned long align,
  64                                       unsigned long flags)
  65 {
  66         struct sg_table *table;
  67         ion_phys_addr_t paddr;
  68         int ret;
  69
  70         if (align > PAGE_SIZE)
  71                 return -EINVAL;
  72
  73         table = kmalloc(sizeof(*table), GFP_KERNEL);
  74         if (!table)
  75                 return -ENOMEM;
  76         ret = sg_alloc_table(table, 1, GFP_KERNEL);
  77         if (ret)
  78                 goto err_free;
  79
  80         paddr = ion_carveout_allocate(heap, size, align);
  81         if (paddr == ION_CARVEOUT_ALLOCATE_FAIL) {
  82                 ret = -ENOMEM;
  83                 goto err_free_table;
  84         }
  85
  86         sg_set_page(table->sgl, pfn_to_page(PFN_DOWN(paddr)), size, 0);
  87         buffer->sg_table = table;
  88
  89         return 0;
  90
  91 err_free_table:
  92         sg_free_table(table);
  93 err_free:
  94         kfree(table);
  95         return ret;
  96 }
  97
  98 static void ion_carveout_heap_free(struct ion_buffer *buffer)
  99 {
 100         struct ion_heap *heap = buffer->heap;
 101         struct sg_table *table = buffer->sg_table;
 102         struct page *page = sg_page(table->sgl);
 103         ion_phys_addr_t paddr = PFN_PHYS(page_to_pfn(page));
 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         ion_carveout_free(heap, paddr, buffer->size);
 112         sg_free_table(table);
 113         kfree(table);
 114 }
 115
 116 static struct ion_heap_ops carveout_heap_ops = {
 117         .allocate = ion_carveout_heap_allocate,
 118         .free = ion_carveout_heap_free,
 119         .map_user = ion_heap_map_user,
 120         .map_kernel = ion_heap_map_kernel,
 121         .unmap_kernel = ion_heap_unmap_kernel,
 122 };
 123
 124 struct ion_heap *ion_carveout_heap_create(struct ion_platform_heap *heap_data)
 125 {
 126         struct ion_carveout_heap *carveout_heap;
 127         int ret;
 128
 129         struct page *page;
 130         size_t size;
 131
 132         page = pfn_to_page(PFN_DOWN(heap_data->base));
 133         size = heap_data->size;
 134
 135         ion_pages_sync_for_device(NULL, page, size, DMA_BIDIRECTIONAL);
 136
 137         ret = ion_heap_pages_zero(page, size, pgprot_writecombine(PAGE_KERNEL));
 138         if (ret)
 139                 return ERR_PTR(ret);
 140
 141         carveout_heap = kzalloc(sizeof(*carveout_heap), GFP_KERNEL);
 142         if (!carveout_heap)
 143                 return ERR_PTR(-ENOMEM);
 144
 145         carveout_heap->pool = gen_pool_create(PAGE_SHIFT, -1);
 146         if (!carveout_heap->pool) {
 147                 kfree(carveout_heap);
 148                 return ERR_PTR(-ENOMEM);
 149         }
 150         carveout_heap->base = heap_data->base;
 151         gen_pool_add(carveout_heap->pool, carveout_heap->base, heap_data->size,
 152                      -1);
 153         carveout_heap->heap.ops = &carveout_heap_ops;
 154         carveout_heap->heap.type = ION_HEAP_TYPE_CARVEOUT;
 155         carveout_heap->heap.flags = ION_HEAP_FLAG_DEFER_FREE;
 156
 157         return &carveout_heap->heap;
 158 }
 159
 160 void ion_carveout_heap_destroy(struct ion_heap *heap)
 161 {
 162         struct ion_carveout_heap *carveout_heap =
 163              container_of(heap, struct  ion_carveout_heap, heap);
 164
 165         gen_pool_destroy(carveout_heap->pool);
 166         kfree(carveout_heap);
 167         carveout_heap = NULL;
 168 }