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

[Milan Broz <gmazyland@gmail.com>]

The /sys/block/<disk>/integrity fields are historically set if PI
is enabled. It is not set if some upper layer uses integrity metadata
for non-PI format.
Document it.

Signed-off-by: Milan Broz <gmazyland@gmail.com>
---
 Documentation/ABI/stable/sysfs-block | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/Documentation/ABI/stable/sysfs-block b/Documentation/ABI/stable/sysfs-block
index 0cceb2badc83..f67fd46f15b6 100644
--- a/Documentation/ABI/stable/sysfs-block
+++ b/Documentation/ABI/stable/sysfs-block
@@ -109,6 +109,8 @@ Contact:	Martin K. Petersen <martin.petersen@oracle.com>
 Description:
 		Indicates whether a storage device is capable of storing
 		integrity metadata. Set if the device is T10 PI-capable.
+		This flag is set if a PI profile is enabled.
+		It is not set when non-PI metadata are used.
 
 
 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".
 
 
 What:		/sys/block/<disk>/integrity/protection_interval_bytes
@@ -142,7 +146,10 @@ Date:		June 2008
 Contact:	Martin K. Petersen <martin.petersen@oracle.com>
 Description:
 		Number of bytes of integrity tag space available per
-		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.
 
 
 What:		/sys/block/<disk>/integrity/write_generate
-- 
2.47.2