Re: [PATCH v1 4/4] tcmu: Make dev_config configurable

[Mike Christie <mchristi@redhat.com>]

On 05/26/2017 09:27 AM, Bryant G. Ly wrote:
> This allows for userspace to change the device path after
> it has been created. Thus giving the user the ability to change
> the path. The use case for this is to allow for virtual optical
> to have media change.
> 
> Signed-off-by: Bryant G. Ly <bryantly@linux.vnet.ibm.com>
> ---
>  drivers/target/target_core_user.c | 40 +++++++++++++++++++++++++++++++++++++++
>  1 file changed, 40 insertions(+)
> 
> diff --git a/drivers/target/target_core_user.c b/drivers/target/target_core_user.c
> index c8c84b7..3036a57 100644
> --- a/drivers/target/target_core_user.c
> +++ b/drivers/target/target_core_user.c
> @@ -1548,6 +1548,45 @@ static ssize_t tcmu_cmd_time_out_store(struct config_item *item, const char *pag
>  }
>  CONFIGFS_ATTR(tcmu_, cmd_time_out);
>  
> +static ssize_t tcmu_dev_path_show(struct config_item *item, char *page)
> +{
> +	struct se_dev_attrib *da = container_of(to_config_group(item),
> +						struct se_dev_attrib, da_group);
> +	struct tcmu_dev *udev = TCMU_DEV(da->da_dev);
> +
> +	return snprintf(page, PAGE_SIZE, "%s\n", udev->dev_config);
> +}
> +
> +static ssize_t tcmu_dev_path_store(struct config_item *item, const char *page,
> +				   size_t count)
> +{
> +	struct se_dev_attrib *da = container_of(to_config_group(item),
> +						struct se_dev_attrib, da_group);
> +	struct tcmu_dev *udev = TCMU_DEV(da->da_dev);
> +	char *copy = NULL;
> +
> +	copy = kstrdup(page, GFP_KERNEL);

Cen remove the extra newline

> +
> +	if (!copy)
> +		return -EINVAL;
> +
> +	strcpy(udev->dev_config, copy);


Missing a kree(copy);


> +
> +	/* Check if device has been configured before */
> +	if (tcmu_dev_configured(udev)) {
> +		ret = tcmu_netlink_event(TCMU_CMD_RECONFIG_DEVICE,
> +					 udev->uio_info.name,
> +					 udev->uio_info.uio_dev->minor);
> +		if (ret) {
> +			pr_err("Unable to reconfigure device\n");
> +			return ret;
> +		}
> +	}
> +
> +	return count;
> +}
> +CONFIGFS_ATTR(tcmu_, dev_path);
> +
>  static ssize_t tcmu_dev_size_show(struct config_item *item, char *page)
>  {
>  	struct se_dev_attrib *da = container_of(to_config_group(item),
> @@ -1626,6 +1665,7 @@ CONFIGFS_ATTR(tcmu_, emulate_write_cache);
>  
>  struct configfs_attribute *tcmu_attrib_attrs[] = {
>  	&tcmu_attr_cmd_time_out,
> +	&tcmu_attr_dev_path,
>  	&tcmu_attr_dev_size,
>  	&tcmu_attr_emulate_write_cache,
>  	NULL,
>