static long dma_buf_ioctl()

in dma-buf.c [328:374]

• 39 lines of code
• 10 McCabe index (conditional complexity)

static long dma_buf_ioctl(struct file *file,
			  unsigned int cmd, unsigned long arg)
{
	struct dma_buf *dmabuf;
	struct dma_buf_sync sync;
	enum dma_data_direction direction;
	int ret;

	dmabuf = file->private_data;

	switch (cmd) {
	case DMA_BUF_IOCTL_SYNC:
		if (copy_from_user(&sync, (void __user *) arg, sizeof(sync)))
			return -EFAULT;

		if (sync.flags & ~DMA_BUF_SYNC_VALID_FLAGS_MASK)
			return -EINVAL;

		switch (sync.flags & DMA_BUF_SYNC_RW) {
		case DMA_BUF_SYNC_READ:
			direction = DMA_FROM_DEVICE;
			break;
		case DMA_BUF_SYNC_WRITE:
			direction = DMA_TO_DEVICE;
			break;
		case DMA_BUF_SYNC_RW:
			direction = DMA_BIDIRECTIONAL;
			break;
		default:
			return -EINVAL;
		}

		if (sync.flags & DMA_BUF_SYNC_END)
			ret = dma_buf_end_cpu_access(dmabuf, direction);
		else
			ret = dma_buf_begin_cpu_access(dmabuf, direction);

		return ret;

	case DMA_BUF_SET_NAME_A:
	case DMA_BUF_SET_NAME_B:
		return dma_buf_set_name(dmabuf, (const char __user *)arg);

	default:
		return -ENOTTY;
	}
}