Update Linux to v5.4.2
Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/fs/btrfs/misc.h b/fs/btrfs/misc.h
new file mode 100644
index 0000000..7d56492
--- /dev/null
+++ b/fs/btrfs/misc.h
@@ -0,0 +1,50 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef BTRFS_MISC_H
+#define BTRFS_MISC_H
+
+#include <linux/sched.h>
+#include <linux/wait.h>
+#include <asm/div64.h>
+
+#define in_range(b, first, len) ((b) >= (first) && (b) < (first) + (len))
+
+static inline void cond_wake_up(struct wait_queue_head *wq)
+{
+ /*
+ * This implies a full smp_mb barrier, see comments for
+ * waitqueue_active why.
+ */
+ if (wq_has_sleeper(wq))
+ wake_up(wq);
+}
+
+static inline void cond_wake_up_nomb(struct wait_queue_head *wq)
+{
+ /*
+ * Special case for conditional wakeup where the barrier required for
+ * waitqueue_active is implied by some of the preceding code. Eg. one
+ * of such atomic operations (atomic_dec_and_return, ...), or a
+ * unlock/lock sequence, etc.
+ */
+ if (waitqueue_active(wq))
+ wake_up(wq);
+}
+
+static inline u64 div_factor(u64 num, int factor)
+{
+ if (factor == 10)
+ return num;
+ num *= factor;
+ return div_u64(num, 10);
+}
+
+static inline u64 div_factor_fine(u64 num, int factor)
+{
+ if (factor == 100)
+ return num;
+ num *= factor;
+ return div_u64(num, 100);
+}
+
+#endif