Re: [v5 01/12] struct device: Add function callback durable_name

From: Sergei Shtylyov <sergei.shtylyov@gmail.com>
To: Tony Asleson <tasleson@redhat.com>,
	linux-scsi@vger.kernel.org, linux-block@vger.kernel.org,
	linux-ide@vger.kernel.org
Subject: Re: [v5 01/12] struct device: Add function callback durable_name
Date: Sat, 26 Sep 2020 12:08:05 +0300	[thread overview]
Message-ID: <1cfc145b-180a-d906-5d9b-638c483177c7@gmail.com> (raw)
In-Reply-To: <20200925161929.1136806-2-tasleson@redhat.com>

On 25.09.2020 19:19, Tony Asleson wrote:

> Function callback and function to be used to write a persistent
> durable name to the supplied character buffer.  This will be used to add
> structured key-value data to log messages for hardware related errors
> which allows end users to correlate message and specific hardware.
> 
> Signed-off-by: Tony Asleson <tasleson@redhat.com>
> ---
>   drivers/base/core.c    | 24 ++++++++++++++++++++++++
>   include/linux/device.h |  4 ++++
>   2 files changed, 28 insertions(+)
> 
> diff --git a/drivers/base/core.c b/drivers/base/core.c
> index 05d414e9e8a4..88696ade8bfc 100644
> --- a/drivers/base/core.c
> +++ b/drivers/base/core.c
> @@ -2489,6 +2489,30 @@ int dev_set_name(struct device *dev, const char *fmt, ...)
>   }
>   EXPORT_SYMBOL_GPL(dev_set_name);
>   
> +/**
> + * dev_durable_name - Write "DURABLE_NAME"=<durable name> in buffer
> + * @dev: device
> + * @buffer: character buffer to write results
> + * @len: length of buffer
> + * @return: Number of bytes written to buffer

    This is not how the kernel-doc commenta describe the function result, IIRC...

> + */
> +int dev_durable_name(const struct device *dev, char *buffer, size_t len)
> +{
> +	int tmp, dlen;
> +
> +	if (dev && dev->durable_name) {
> +		tmp = snprintf(buffer, len, "DURABLE_NAME=");
> +		if (tmp < len) {
> +			dlen = dev->durable_name(dev, buffer + tmp,
> +							len - tmp);
> +			if (dlen > 0 && ((dlen + tmp) < len))
> +				return dlen + tmp;
> +		}
> +	}
> +	return 0;
> +}
> +EXPORT_SYMBOL_GPL(dev_durable_name);
> +
>   /**
>    * device_to_dev_kobj - select a /sys/dev/ directory for the device
>    * @dev: device
[...]

MBR, Sergei