From: Frederic TEMPORELLI <frederic.temporelli@ext.bull.net>

Aic79xx driver for Adaptec 39320 supports 64-bit addressing, but the
initialization code of the driver is wrong: it tests the available memory
size instead of testing the maximum available memory address.  This is
necessary to support servers that provides 1 Terabyte of physical memory
space addressing.

Attached is the suggested patch to solve this issue.

[akpm@osdl.org: extern decls never go in .c files]
Signed-off-by: <xavier.bru@bull.net>
Signed-off-by: <frederic.temporelli@bull.net>
Cc: Hannes Reinecke <hare@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
---

 drivers/scsi/aic7xxx/aic79xx_osm.c |    8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff -puN drivers/scsi/aic7xxx/aic79xx_osm.c~aic79xx-wrong-max-memory-at-driver-init drivers/scsi/aic7xxx/aic79xx_osm.c
--- a/drivers/scsi/aic7xxx/aic79xx_osm.c~aic79xx-wrong-max-memory-at-driver-init
+++ a/drivers/scsi/aic7xxx/aic79xx_osm.c
@@ -44,6 +44,7 @@
 
 #include "aic79xx_osm.h"
 #include "aic79xx_inline.h"
+#include <linux/blkdev.h>
 #include <scsi/scsicam.h>
 
 static struct scsi_transport_template *ahd_linux_transport_template = NULL;
@@ -1130,10 +1131,9 @@ ahd_linux_register_host(struct ahd_softc
 uint64_t
 ahd_linux_get_memsize(void)
 {
-	struct sysinfo si;
-
-	si_meminfo(&si);
-	return ((uint64_t)si.totalram << PAGE_SHIFT);
+	/* Need to take in account the max physical address in case
+	 * of discontiguous memory. */
+	return ((uint64_t)blk_max_pfn << PAGE_SHIFT);
 }
 
 /*
_