summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorStephen M. Cameron <scameron@beardog.cce.hp.com>2010-02-26 23:01:12 +0100
committerJens Axboe <jens.axboe@oracle.com>2010-02-28 19:42:31 +0100
commit58daa9ce96b847ed130453f5fdd63c579fb1f84f (patch)
tree3d2fb7cbb4882d691dc34745ad115897feb73cbc
parentcfq-iosched: rethink seeky detection for SSDs (diff)
downloadlinux-58daa9ce96b847ed130453f5fdd63c579fb1f84f.tar.xz
linux-58daa9ce96b847ed130453f5fdd63c579fb1f84f.zip
cciss: clarify command list padding calculation
cciss: clarify command list padding calculation Signed-off-by: Stephen M. Cameron <scameron@beardog.cce.hp.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
-rw-r--r--drivers/block/cciss_cmd.h9
1 files changed, 7 insertions, 2 deletions
diff --git a/drivers/block/cciss_cmd.h b/drivers/block/cciss_cmd.h
index 25f97623bacf..515c9f03c201 100644
--- a/drivers/block/cciss_cmd.h
+++ b/drivers/block/cciss_cmd.h
@@ -168,9 +168,14 @@ typedef struct _SGDescriptor_struct {
#define CMD_MSG_STALE 0xff
/* This structure needs to be divisible by 8 for new
- * indexing method.
+ * indexing method. PAD_32 and PAD_64 can be adjusted
+ * independently as needed for 32-bit and 64-bits systems.
*/
-#define PADSIZE (sizeof(long) - 4)
+#define IS_64_BIT ((sizeof(long) - 4)/4)
+#define IS_32_BIT (!IS_64_BIT)
+#define PAD_32 (0)
+#define PAD_64 (4)
+#define PADSIZE (IS_32_BIT * PAD_32 + IS_64_BIT * PAD_64)
typedef struct _CommandList_struct {
CommandListHeader_struct Header;
RequestBlock_struct Request;