Merge branch 'for-linus' of git://git.kernel.dk/linux-block

Says Jens:

 "Time to push off some of the pending items.  I really wanted to wait
  until we had the regression nailed, but alas it's not quite there yet.
  But I'm very confident that it's "just" a missing expire on exit, so
  fix from Tejun should be fairly trivial.  I'm headed out for a week on
  the slopes.

  - Killing the barrier part of mtip32xx.  It doesn't really support
    barriers, and it doesn't need them (writes are fully ordered).

  - A few fixes from Dan Carpenter, preventing overflows of integer
    multiplication.

  - A fixup for loop, fixing a previous commit that didn't quite solve
    the partial read problem from Dave Young.

  - A bio integer overflow fix from Kent Overstreet.

  - Improvement/fix of the door "keep locked" part of the cdrom shared
    code from Paolo Benzini.

  - A few cfq fixes from Shaohua Li.

  - A fix for bsg sysfs warning when removing a file it did not create
    from Stanislaw Gruszka.

  - Two fixes for floppy from Vivek, preventing a crash.

  - A few block core fixes from Tejun.  One killing the over-optimized
    ioc exit path, cleaning that up nicely.  Two others fixing an oops
    on elevator switch, due to calling into the scheduler merge check
    code without holding the queue lock."

* 'for-linus' of git://git.kernel.dk/linux-block:
  block: fix lockdep warning on io_context release put_io_context()
  relay: prevent integer overflow in relay_open()
  loop: zero fill bio instead of return -EIO for partial read
  bio: don't overflow in bio_get_nr_vecs()
  floppy: Fix a crash during rmmod
  floppy: Cleanup disk->queue before caling put_disk() if add_disk() was never called
  cdrom: move shared static to cdrom_device_info
  bsg: fix sysfs link remove warning
  block: don't call elevator callbacks for plug merges
  block: separate out blk_rq_merge_ok() and blk_try_merge() from elevator functions
  mtip32xx: removed the irrelevant argument of mtip_hw_submit_io() and the unused member of struct driver_data
  block: strip out locking optimization in put_io_context()
  cdrom: use copy_to_user() without the underscores
  block: fix ioc locking warning
  block: fix NULL icq_cache reference
  block,cfq: change code order

1 files changed, 9 insertions, 15 deletions

diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c
index ee55019066a1..d0ba50533668 100644
--- a/block/cfq-iosched.c
+++ b/block/cfq-iosched.c
@@ -1699,18 +1699,11 @@ static int cfq_allow_merge(struct request_queue *q, struct request *rq,
 
 	/*
 	 * Lookup the cfqq that this bio will be queued with and allow
-	 * merge only if rq is queued there.  This function can be called
-	 * from plug merge without queue_lock.  In such cases, ioc of @rq
-	 * and %current are guaranteed to be equal.  Avoid lookup which
-	 * requires queue_lock by using @rq's cic.
+	 * merge only if rq is queued there.
 	 */
-	if (current->io_context == RQ_CIC(rq)->icq.ioc) {
-		cic = RQ_CIC(rq);
-	} else {
-		cic = cfq_cic_lookup(cfqd, current->io_context);
-		if (!cic)
-			return false;
-	}
+	cic = cfq_cic_lookup(cfqd, current->io_context);
+	if (!cic)
+		return false;
 
 	cfqq = cic_to_cfqq(cic, cfq_bio_sync(bio));
 	return cfqq == RQ_CFQQ(rq);
@@ -1794,7 +1787,7 @@ __cfq_slice_expired(struct cfq_data *cfqd, struct cfq_queue *cfqq,
 		cfqd->active_queue = NULL;
 
 	if (cfqd->active_cic) {
-		put_io_context(cfqd->active_cic->icq.ioc, cfqd->queue);
+		put_io_context(cfqd->active_cic->icq.ioc);
 		cfqd->active_cic = NULL;
 	}
 }
@@ -3117,17 +3110,18 @@ cfq_should_preempt(struct cfq_data *cfqd, struct cfq_queue *new_cfqq,
  */
 static void cfq_preempt_queue(struct cfq_data *cfqd, struct cfq_queue *cfqq)
 {
+	enum wl_type_t old_type = cfqq_type(cfqd->active_queue);
+
 	cfq_log_cfqq(cfqd, cfqq, "preempt");
+	cfq_slice_expired(cfqd, 1);
 
 	/*
 	 * workload type is changed, don't save slice, otherwise preempt
 	 * doesn't happen
 	 */
-	if (cfqq_type(cfqd->active_queue) != cfqq_type(cfqq))
+	if (old_type != cfqq_type(cfqq))
 		cfqq->cfqg->saved_workload_slice = 0;
 
-	cfq_slice_expired(cfqd, 1);
-
 	/*
 	 * Put the new queue at the front of the of the current list,
 	 * so we know that it will be selected next.