# This is a BitKeeper generated patch for the following project:
# Project Name: Linux kernel tree
# This patch format is intended for GNU patch command version 2.5 or higher.
# This patch includes the following deltas:
#	           ChangeSet	1.816   -> 1.817  
#	drivers/block/ll_rw_blk.c	1.126   -> 1.127  
#	drivers/block/elevator.c	1.31    -> 1.32   
#
# The following is the BitKeeper ChangeSet Log
# --------------------------------------------
# 02/10/28	axboe@burns.home.kernel.dk	1.817
# Cleanup the last_merge logic. There are two reasons for clearing last_merge
# when we are dealing with integrity, and these are:
# 
# o Clear when handing the request to the driver, so we don't merge on
#   a started request.
# 
# o Clear when a request is taken off the list. This cannot be done from
#   the driver (above case would already have been hit), but it can happen
#   when we merge two requests.
# 
# This makes it a lot nicer, it was always peculiar how we cleared in
# put_request.
# --------------------------------------------
#
diff -Nru a/drivers/block/elevator.c b/drivers/block/elevator.c
--- a/drivers/block/elevator.c	Mon Oct 28 18:11:33 2002
+++ b/drivers/block/elevator.c	Mon Oct 28 18:11:33 2002
@@ -344,6 +344,16 @@
 {
 	elevator_t *e = &q->elevator;
 
+	/*
+	 * the main clearing point for q->last_merge is on retrieval of
+	 * request by driver (it calls elv_next_request()), but it _can_
+	 * also happen here if a request is added to the queue but later
+	 * deleted without ever being given to driver (merged with another
+	 * request).
+	 */
+	if (&rq->queuelist == q->last_merge)
+		q->last_merge = NULL;
+
 	if (e->elevator_remove_req_fn)
 		e->elevator_remove_req_fn(q, rq);
 }
diff -Nru a/drivers/block/ll_rw_blk.c b/drivers/block/ll_rw_blk.c
--- a/drivers/block/ll_rw_blk.c	Mon Oct 28 18:11:33 2002
+++ b/drivers/block/ll_rw_blk.c	Mon Oct 28 18:11:33 2002
@@ -1509,11 +1509,6 @@
 	req->q = NULL;
 	req->rl = NULL;
 
-	if (q) {
-		if (q->last_merge == &req->queuelist)
-			q->last_merge = NULL;
-	}
-
 	/*
 	 * Request may not have originated from ll_rw_blk. if not,
 	 * it didn't come out of our reserved rq pools