block: make blk_iopoll_prep_sched() follow normal 0/1 return convention

Return 0 if we successfully marked this iopoll structure as ours for
scheduling, instead of 1.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

diff --git a/include/linux/blk-iopoll.h b/include/linux/blk-iopoll.h
index b2e1739a2e7b897c339fc05d7920af5fb98692fc..308734d3d4a2365f6e3639a4ddc4ed33d41f36ce 100644 (file)
--- a/include/linux/blk-iopoll.h
+++ b/include/linux/blk-iopoll.h
@@ -18,10 +18,17 @@ enum {
        IOPOLL_F_DISABLE        = 1,
 };
 
+/*
+ * Returns 0 if we successfully set the IOPOLL_F_SCHED bit, indicating
+ * that we were the first to acquire this iop for scheduling. If this iop
+ * is currently disabled, return "failure".
+ */
 static inline int blk_iopoll_sched_prep(struct blk_iopoll *iop)
 {
-       return !test_bit(IOPOLL_F_DISABLE, &iop->state) &&
-               !test_and_set_bit(IOPOLL_F_SCHED, &iop->state);
+       if (!test_bit(IOPOLL_F_DISABLE, &iop->state))
+               return test_and_set_bit(IOPOLL_F_SCHED, &iop->state);
+
+       return 1;
 }
 
 static inline int blk_iopoll_disable_pending(struct blk_iopoll *iop)