[SCSI] aacraid: add parameter to control FUA and SYNCHRONIZE_CACHE policy

aacraid.cache parameter, Disable Queue Flush commands:
        bit 0 - Disable FUA in WRITE SCSI commands
        bit 1 - Disable SYNCHRONIZE_CACHE SCSI command
        bit 2 - Disable only if Battery not protecting adapter supplied Cache

e.g.: aacraid.cache=7 will disable the FUA and SYNCHRONIZE_CACHE
commands if the adapter has reported that it's cache is battery backed
up.

This parameter permits experimentation with tradeoffs between
performance and caching policy.

Signed-off-by: Mark Salyzyn <aacraid@adaptec.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/drivers/scsi/aacraid/aacraid.h b/drivers/scsi/aacraid/aacraid.h
index 734623af9c45..7bb3d9fde713 100644
--- a/drivers/scsi/aacraid/aacraid.h
+++ b/drivers/scsi/aacraid/aacraid.h
@@ -1016,6 +1016,7 @@ struct aac_dev
          * lets break them out so we don't have to do an AND to check them
          */
         u8                      nondasd_support; 
+        u8                      cache_protected;
         u8                      dac_support;
         u8                      raid_scsi_mode;
         u8                      comm_interface;
@@ -1770,6 +1771,7 @@ extern struct aac_common aac_config;
 #define                 AifEnConfigChange       3       /* Adapter configuration change */
 #define                 AifEnContainerChange    4       /* Container configuration change */
 #define                 AifEnDeviceFailure      5       /* SCSI device failed */
+#define                 AifEnBatteryEvent       14      /* Change in Battery State */
 #define                 AifEnAddContainer       15      /* A new array was created */
 #define                 AifEnDeleteContainer    16      /* A container was deleted */
 #define                 AifEnExpEvent           23      /* Firmware Event Log */