block: kill rq->data

Now that all block request data transfer is done via bio, rq->data
isn't used.  Kill it.

While at it, make the roles of rq->special and buffer clear.

[ Impact: drop now unncessary field from struct request ]

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Boaz Harrosh <bharrosh@panasas.com>

1 files changed, 2 insertions, 3 deletions

diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index cfeb3c2feb27..12c545e2737c 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -211,8 +211,8 @@ struct request {
 
         unsigned short ioprio;
 
-        void *special;
-        char *buffer;
+        void *special;          /* opaque pointer available for LLD use */
+        char *buffer;           /* kaddr of the current segment if available */
 
         int tag;
         int errors;
@@ -229,7 +229,6 @@ struct request {
         unsigned int data_len;
         unsigned int extra_len; /* length of alignment and padding */
         unsigned int sense_len;
-        void *data;
         void *sense;
 
         unsigned long deadline;