static int tcmu_configure_device()

in target_core_user.c [2170:2284]

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

static int tcmu_configure_device(struct se_device *dev)
{
	struct tcmu_dev *udev = TCMU_DEV(dev);
	struct uio_info *info;
	struct tcmu_mailbox *mb;
	size_t data_size;
	int ret = 0;

	ret = tcmu_update_uio_info(udev);
	if (ret)
		return ret;

	info = &udev->uio_info;

	mutex_lock(&udev->cmdr_lock);
	udev->data_bitmap = bitmap_zalloc(udev->max_blocks, GFP_KERNEL);
	mutex_unlock(&udev->cmdr_lock);
	if (!udev->data_bitmap) {
		ret = -ENOMEM;
		goto err_bitmap_alloc;
	}

	mb = vzalloc(MB_CMDR_SIZE);
	if (!mb) {
		ret = -ENOMEM;
		goto err_vzalloc;
	}

	/* mailbox fits in first part of CMDR space */
	udev->mb_addr = mb;
	udev->cmdr = (void *)mb + CMDR_OFF;
	udev->cmdr_size = CMDR_SIZE;
	udev->data_off = MB_CMDR_SIZE;
	data_size = TCMU_MBS_TO_PAGES(udev->data_area_mb) << PAGE_SHIFT;
	udev->mmap_pages = (data_size + MB_CMDR_SIZE) >> PAGE_SHIFT;
	udev->data_blk_size = udev->data_pages_per_blk * PAGE_SIZE;
	udev->dbi_thresh = 0; /* Default in Idle state */

	/* Initialise the mailbox of the ring buffer */
	mb->version = TCMU_MAILBOX_VERSION;
	mb->flags = TCMU_MAILBOX_FLAG_CAP_OOOC |
		    TCMU_MAILBOX_FLAG_CAP_READ_LEN |
		    TCMU_MAILBOX_FLAG_CAP_TMR |
		    TCMU_MAILBOX_FLAG_CAP_KEEP_BUF;
	mb->cmdr_off = CMDR_OFF;
	mb->cmdr_size = udev->cmdr_size;

	WARN_ON(!PAGE_ALIGNED(udev->data_off));
	WARN_ON(data_size % PAGE_SIZE);

	info->version = __stringify(TCMU_MAILBOX_VERSION);

	info->mem[0].name = "tcm-user command & data buffer";
	info->mem[0].addr = (phys_addr_t)(uintptr_t)udev->mb_addr;
	info->mem[0].size = data_size + MB_CMDR_SIZE;
	info->mem[0].memtype = UIO_MEM_NONE;

	info->irqcontrol = tcmu_irqcontrol;
	info->irq = UIO_IRQ_CUSTOM;

	info->mmap = tcmu_mmap;
	info->open = tcmu_open;
	info->release = tcmu_release;

	ret = uio_register_device(tcmu_root_device, info);
	if (ret)
		goto err_register;

	/* User can set hw_block_size before enable the device */
	if (dev->dev_attrib.hw_block_size == 0)
		dev->dev_attrib.hw_block_size = 512;
	/* Other attributes can be configured in userspace */
	if (!dev->dev_attrib.hw_max_sectors)
		dev->dev_attrib.hw_max_sectors = 128;
	if (!dev->dev_attrib.emulate_write_cache)
		dev->dev_attrib.emulate_write_cache = 0;
	dev->dev_attrib.hw_queue_depth = 128;

	/* If user didn't explicitly disable netlink reply support, use
	 * module scope setting.
	 */
	if (udev->nl_reply_supported >= 0)
		udev->nl_reply_supported = tcmu_kern_cmd_reply_supported;

	/*
	 * Get a ref incase userspace does a close on the uio device before
	 * LIO has initiated tcmu_free_device.
	 */
	kref_get(&udev->kref);

	ret = tcmu_send_dev_add_event(udev);
	if (ret)
		goto err_netlink;

	mutex_lock(&root_udev_mutex);
	list_add(&udev->node, &root_udev);
	mutex_unlock(&root_udev_mutex);

	return 0;

err_netlink:
	kref_put(&udev->kref, tcmu_dev_kref_release);
	uio_unregister_device(&udev->uio_info);
err_register:
	vfree(udev->mb_addr);
	udev->mb_addr = NULL;
err_vzalloc:
	bitmap_free(udev->data_bitmap);
	udev->data_bitmap = NULL;
err_bitmap_alloc:
	kfree(info->name);
	info->name = NULL;

	return ret;
}