[PATCH v6 4/6] smartpqi: add host attributes

[Don Brace <don.brace@microchip.com>]

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 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>
---
 man4/smartpqi.4 | 62 +++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 62 insertions(+)

diff --git a/man4/smartpqi.4 b/man4/smartpqi.4
index 5ff134a4821a..6305e15a912b 100644
--- a/man4/smartpqi.4
+++ b/man4/smartpqi.4
@@ -236,6 +236,68 @@ $ \c
 Adaptec
 .EE
 .in
+.TP
+.I /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
+.I /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
+.I /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
-- 
2.42.0.296.g493f462273