linux-4.4.1/ion_cma_allocate() の履歴(No.1)

• 履歴一覧
• 差分 を表示
• 現在との差分 を表示
• ソース を表示
• linux-4.4.1/ion_cma_allocate() へ行く。
  • 1 (2017-09-15 (金) 18:41:34)
  • 2 (2017-09-15 (金) 18:46:02)

参照元†

• linux-4.4.1/ion_cma_ops(global)

説明†

• パス: linux-4.4.1/drivers/staging/android/ion/ion_cma_heap.c

• FIXME: これは何？
  • 説明

引数†

• struct ion_heap *heap
  • [[linux-4.4.1/]]
• struct ion_buffer *buffer
  • [[linux-4.4.1/]]
• unsigned long len
  • [[linux-4.4.1/]]
• unsigned long align
  • [[linux-4.4.1/]]
• unsigned long flags
  • [[linux-4.4.1/]]

返り値†

参考†

実装†

/* ION CMA heap operations functions */
static int ion_cma_allocate(struct ion_heap *heap, struct ion_buffer *buffer,
                            unsigned long len, unsigned long align,
                            unsigned long flags)
{
        struct ion_cma_heap *cma_heap = to_cma_heap(heap);
        struct device *dev = cma_heap->dev;
        struct ion_cma_buffer_info *info;

• • linux-4.4.1/ion_cma_heap
  • linux-4.4.1/to_cma_heap()
  • linux-4.4.1/device
  • linux-4.4.1/ion_cma_buffer_info

        dev_dbg(dev, "Request buffer allocation len %ld\n", len);

• • linux-4.4.1/dev_dbg()

        if (buffer->flags & ION_FLAG_CACHED)
                return -EINVAL;

        if (align > PAGE_SIZE)
                return -EINVAL;

        info = kzalloc(sizeof(struct ion_cma_buffer_info), GFP_KERNEL);
        if (!info)
                return ION_CMA_ALLOCATE_FAILED;

• • linux-4.4.1/kzalloc()

        info->cpu_addr = dma_alloc_coherent(dev, len, &(info->handle),
                                                GFP_HIGHUSER | __GFP_ZERO);

        if (!info->cpu_addr) {
                dev_err(dev, "Fail to allocate buffer\n");
                goto err;
        }

• • linux-4.4.1/dma_alloc_coherent()

        info->table = kmalloc(sizeof(struct sg_table), GFP_KERNEL);
        if (!info->table)
                goto free_mem;

• • linux-4.4.1/kmalloc()
  • linux-4.4.1/sg_table

        if (dma_get_sgtable(dev, info->table, info->cpu_addr, info->handle,
                            len))
                goto free_table;

• • linux-4.4.1/dma_get_sgtable()

        /* keep this for memory release */
        buffer->priv_virt = info;
        dev_dbg(dev, "Allocate buffer %p\n", buffer);
        return 0;

free_table:
        kfree(info->table);

• • linux-4.4.1/kfree()

free_mem:
        dma_free_coherent(dev, len, info->cpu_addr, info->handle);

• • linux-4.4.1/dma_free_coherent()

err:
        kfree(info);
        return ION_CMA_ALLOCATE_FAILED;
}

コメント†