[SCSI] Support devices with protection information

Implement support for DMA of protection information for devices that
are data integrity capable.

 - Add support for mapping an extra scatter-gather list containing
   the protection information.

 - Allocate protection scsi_data_buffer if host is DIX (integrity DMA)
   capable.

 - Accessor function for checking whether a device has protection
   enabled.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

1 files changed, 5 insertions, 0 deletions

diff --git a/include/scsi/scsi_device.h b/include/scsi/scsi_device.h
index 4deb9349eebf..9cecc409f0f8 100644
--- a/include/scsi/scsi_device.h
+++ b/include/scsi/scsi_device.h
@@ -423,6 +423,11 @@ static inline int scsi_device_enclosure(struct scsi_device *sdev)
         return sdev->inquiry[6] & (1<<6);
 }
 
+static inline int scsi_device_protection(struct scsi_device *sdev)
+{
+        return sdev->inquiry[5] & (1<<0);
+}
+
 #define MODULE_ALIAS_SCSI_DEVICE(type) \
         MODULE_ALIAS("scsi:t-" __stringify(type) "*")
 #define SCSI_DEVICE_MODALIAS_FMT "scsi:t-0x%02x"