workqueue: define masks for work flags and conditionalize STATIC flags

Work flags are about to see more traditional mask handling.  Define
WORK_STRUCT_*_BIT as the bit position constant and redefine
WORK_STRUCT_* as bit masks.  Also, make WORK_STRUCT_STATIC_* flags
conditional

While at it, re-define these constants as enums and use
WORK_STRUCT_STATIC instead of hard-coding 2 in
WORK_DATA_STATIC_INIT().

Signed-off-by: Tejun Heo <tj@kernel.org>
diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index 68e4dd8..5c49d76 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -115,7 +115,7 @@
 		 * statically initialized. We just make sure that it
 		 * is tracked in the object tracker.
 		 */
-		if (test_bit(WORK_STRUCT_STATIC, work_data_bits(work))) {
+		if (test_bit(WORK_STRUCT_STATIC_BIT, work_data_bits(work))) {
 			debug_object_init(work, &work_debug_descr);
 			debug_object_activate(work, &work_debug_descr);
 			return 0;
@@ -232,7 +232,7 @@
 	BUG_ON(!work_pending(work));
 
 	atomic_long_set(&work->data, (unsigned long)cwq | work_static(work) |
-			(1UL << WORK_STRUCT_PENDING) | extra_flags);
+			WORK_STRUCT_PENDING | extra_flags);
 }
 
 /*
@@ -330,7 +330,7 @@
 {
 	int ret = 0;
 
-	if (!test_and_set_bit(WORK_STRUCT_PENDING, work_data_bits(work))) {
+	if (!test_and_set_bit(WORK_STRUCT_PENDING_BIT, work_data_bits(work))) {
 		__queue_work(cpu, wq, work);
 		ret = 1;
 	}
@@ -380,7 +380,7 @@
 	struct timer_list *timer = &dwork->timer;
 	struct work_struct *work = &dwork->work;
 
-	if (!test_and_set_bit(WORK_STRUCT_PENDING, work_data_bits(work))) {
+	if (!test_and_set_bit(WORK_STRUCT_PENDING_BIT, work_data_bits(work))) {
 		BUG_ON(timer_pending(timer));
 		BUG_ON(!list_empty(&work->entry));
 
@@ -516,7 +516,7 @@
 	 * might deadlock.
 	 */
 	INIT_WORK_ON_STACK(&barr->work, wq_barrier_func);
-	__set_bit(WORK_STRUCT_PENDING, work_data_bits(&barr->work));
+	__set_bit(WORK_STRUCT_PENDING_BIT, work_data_bits(&barr->work));
 	init_completion(&barr->done);
 
 	debug_work_activate(&barr->work);
@@ -628,7 +628,7 @@
 	struct cpu_workqueue_struct *cwq;
 	int ret = -1;
 
-	if (!test_and_set_bit(WORK_STRUCT_PENDING, work_data_bits(work)))
+	if (!test_and_set_bit(WORK_STRUCT_PENDING_BIT, work_data_bits(work)))
 		return 0;
 
 	/*