Re: [PATCH] docs: sysfs-block: Clarify integrity sysfs attributes for non-PI metadata

["Martin K. Petersen" <martin.petersen@oracle.com>]

Milan,

> +		This flag is set if a PI profile is enabled.
> +		It is not set when non-PI metadata are used.

This flag is set to 1 if the storage media is formatted with T10
Protection Information. If the storage media is not formatted with T10
Protection Information, this flag is set to 0.

>  What:		/sys/block/<disk>/integrity/format
> @@ -117,6 +119,8 @@ Contact:	Martin K. Petersen <martin.petersen@oracle.com>
>  Description:
>  		Metadata format for integrity capable block device.
>  		E.g. T10-DIF-TYPE1-CRC.
> +		If the storage device supports metadata but no PI
> +		is used, this field will contain "nop".

This field describes the type of T10 Protection Information that the
block device is capable of sending and receiving. If the device does not
support sending and receiving T10 Protection Information, this field
contains "nop".

> -		512 bytes of data.
> +		protection_interval_bytes, which is typically
> +		the device's logical block size.
> +		If the storage device supports metadata but no PI
> +		is used, this field will contain 0.

This field describes the size of the application tag if the storage
device is formatted with T10 Protection Information and permits use of
the application tag. tag_size is reported in bytes and indicates the
space available for adding an opaque tag to each block
(protection_interval_bytes). If the device does not support T10
Protection Information or the device uses the application tag space
internally, this field is set to 0.


Wrt. the size of opaque (non-PI) metadata, I think it would good to have
a dedicated field to describe it.

-- 
Martin K. Petersen	Oracle Linux Engineering