dump: document -f

diff --git a/cmd_debug.c b/cmd_debug.c
index b622cd39d66368b16ef3cc4fad8a1ff1e4075004..e318c6b86fedf7b7506872888dc811d9eb0177b6 100644 (file)
--- a/cmd_debug.c
+++ b/cmd_debug.c
@@ -24,6 +24,7 @@ static void dump_usage(void)
             "\n"
             "Options:\n"
             "  -o output     Output qcow2 image(s)\n"
+            "  -f            Force; overwrite when needed\n"
             "  -h            Display this help and exit\n"
             "Report bugs to <linux-bcache@vger.kernel.org>");
 }