1 files changed, 48 insertions, 0 deletions

diff --git a/include/linux/blk-iopoll.h b/include/linux/blk-iopoll.h
new file mode 100644
index 000000000000..308734d3d4a2
--- /dev/null
+++ b/include/linux/blk-iopoll.h
@@ -0,0 +1,48 @@
+#ifndef BLK_IOPOLL_H
+#define BLK_IOPOLL_H
+
+struct blk_iopoll;
+typedef int (blk_iopoll_fn)(struct blk_iopoll *, int);
+
+struct blk_iopoll {
+        struct list_head list;
+        unsigned long state;
+        unsigned long data;
+        int weight;
+        int max;
+        blk_iopoll_fn *poll;
+};
+
+enum {
+        IOPOLL_F_SCHED          = 0,
+        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)
+{
+        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)
+{
+        return test_bit(IOPOLL_F_DISABLE, &iop->state);
+}
+
+extern void blk_iopoll_sched(struct blk_iopoll *);
+extern void blk_iopoll_init(struct blk_iopoll *, int, blk_iopoll_fn *);
+extern void blk_iopoll_complete(struct blk_iopoll *);
+extern void __blk_iopoll_complete(struct blk_iopoll *);
+extern void blk_iopoll_enable(struct blk_iopoll *);
+extern void blk_iopoll_disable(struct blk_iopoll *);
+
+extern int blk_iopoll_enabled;
+
+#endif