[SCSI] scsi_dh_alua: Evaluate TPGS setting from inquiry data

Instead of issuing a standard inquiry from within the
alua device handler we can evaluate the TPGS setting from
the existing inquiry data of the sdev and save us the I/O.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

1 files changed, 5 insertions, 0 deletions

diff --git a/include/scsi/scsi_device.h b/include/scsi/scsi_device.h
index d371c3ca90c3..f751d37685e0 100644
--- a/include/scsi/scsi_device.h
+++ b/include/scsi/scsi_device.h
@@ -471,6 +471,11 @@ static inline int scsi_device_protection(struct scsi_device *sdev)
         return sdev->scsi_level > SCSI_2 && sdev->inquiry[5] & (1<<0);
 }
 
+static inline int scsi_device_tpgs(struct scsi_device *sdev)
+{
+        return sdev->inquiry ? (sdev->inquiry[5] >> 4) & 0x3 : 0;
+}
+
 #define MODULE_ALIAS_SCSI_DEVICE(type) \
         MODULE_ALIAS("scsi:t-" __stringify(type) "*")
 #define SCSI_DEVICE_MODALIAS_FMT "scsi:t-0x%02x"