smartpqi.4: Add host attributes

Add in some host level sysfs entries:
enable_stream_detection - Send RAID 5/6 writes down the normal I/O path.
                          Allow for full-stripe write requests.
ssd_smart_path_enabled  - Indicates that our Accelerated I/O (AIO) path
                          is enabled (AIO).
enable_r5_writes        - Allow RAID 5 write operations down the AIO path.
enable_r6_writes        - Allow RAID 6 write operations down the AIO path.

Reviewed-by: Scott Benesh <scott.benesh@microchip.com>
Reviewed-by: Scott Teel <scott.teel@microchip.com>
Reviewed-by: Mike McGowen <mike.mcgowen@microchip.com>
Reviewed-by: Kevin Barnett <kevin.barnett@microchip.com>
Signed-off-by: Don Brace <don.brace@microchip.com>
Signed-off-by: Alejandro Colomar <alx@kernel.org>

diff --git a/man4/smartpqi.4 b/man4/smartpqi.4
index ea19e46bfb7d1f3054f8462f8cd6509a5a977518..9a6eec1b6139987fde6dd96b7e8749a434b33a92 100644 (file)
--- a/man4/smartpqi.4
+++ b/man4/smartpqi.4
@@ -255,6 +255,69 @@ $ \c
 Adaptec
 .EE
 .in
+.TP
+.IR /sys/class/scsi_host/host * /enable_stream_detection
+The
+.I enable_stream_detection
+attribute is read-write.
+This attribute enables/disables stream detection in the driver.
+Enabling stream detection can improve sequential write performance
+for ioaccel-enabled volumes.
+See the
+.BI ssd_smart_path_enabled
+disk attribute section for details on ioaccel-enabled volumes.
+The default value is 1 (stream detection enabled).
+.IP
+Enable example:
+.IP
+.in +4n
+.EX
+$ \c
+.B echo 1 > /sys/class/scsi_host/host1/enable_stream_detection
+.EE
+.in
+.TP
+.IR /sys/class/scsi_host/host * /enable_r5_writes
+The
+.I enable_r5_writes
+attribute is read-write.
+This attribute enables/disables RAID 5 write operations
+for ioaccel-enabled volumes.
+Enabling can improve sequential write performance.
+See the
+.BI ssd_smart_path_enabled
+disk attribute section for details on ioaccel-enabled volumes.
+The default value is 1 (RAID 5 writes enabled).
+.IP
+Enable example:
+.IP
+.in +4n
+.EX
+$ \c
+.B echo 1 > /sys/class/scsi_host/host1/enable_r5_writes
+.EE
+.in
+.TP
+.IR /sys/class/scsi_host/host * /enable_r6_writes
+The
+.I enable_r6_writes
+attribute is read-write.
+This attribute enables/disables RAID 6 write operations
+for ioaccel-enabled volumes.
+Enabling can improve sequential write performance.
+See the
+.BI ssd_smart_path_enabled
+disk attribute section for details on ioaccel-enabled volumes.
+The default value is 1 (RAID 6 writes enabled).
+.IP
+Enable example:
+.IP
+.in +4n
+.EX
+$ \c
+.B echo 1 > /sys/class/scsi_host/host1/enable_r6_writes
+.EE
+.in
 .SS SmartPQI-specific disk attribute files in \f[BI]/sys\fP
 In the file specifications below,
 .I c