dm-crypt: use unbound workqueue for request processing

Use unbound workqueue so that work is automatically ballanced between
available CPUs.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>

---
 drivers/md/dm-crypt.c |    5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

Index: linux-3.10.4-fast/drivers/md/dm-crypt.c
===================================================================
--- linux-3.10.4-fast.orig/drivers/md/dm-crypt.c	2013-07-31 17:03:10.000000000 +0200
+++ linux-3.10.4-fast/drivers/md/dm-crypt.c	2013-07-31 17:03:18.000000000 +0200
@@ -1620,8 +1620,9 @@ static int crypt_ctr(struct dm_target *t
 	cc->crypt_queue = alloc_workqueue("kcryptd",
 					  WQ_NON_REENTRANT|
 					  WQ_CPU_INTENSIVE|
-					  WQ_MEM_RECLAIM,
-					  1);
+					  WQ_MEM_RECLAIM|
+					  WQ_UNBOUND,
+					  num_online_cpus());
 	if (!cc->crypt_queue) {
 		ti->error = "Couldn't create kcryptd queue";
 		goto bad;