ext4: fix symbolic enum printing in trace output

Trace's macro __print_flags() produce raw event's decraration w/o knowing actual
flags value

cat /sys/kernel/debug/tracing/events/ext4/ext4_ext_map_blocks_exit/format
..
__print_flags(REC->mflags, "", { (1 << BH_New),

For that reason we have to explicitly define it via special macro TRACE_DEFINE_ENUM()
Also add missed EXTENT_STATUS_REFERENCED flag.

#Before patch
ext4:ext4_ext_map_blocks_exit: dev 253,0 ino 2 flags  lblk 0 pblk 4177 len 1 mflags 0x20 ret 1
ext4:ext4_ext_map_blocks_exit: dev 253,0 ino 12 flags CREATE lblk 0 pblk 34304 len 1 mflags 0x60 ret 1

#With patch
ext4:ext4_ext_map_blocks_exit: dev 253,0 ino 2 flags  lblk 0 pblk 4177 len 1 mflags M ret 1
ext4:ext4_ext_map_blocks_exit: dev 253,0 ino 12 flags CREATE lblk 0 pblk 34816 len 1 mflags NM ret 1
Signed-off-by: Dmitry Monakhov <dmonakhov@gmail.com>
Link: https://lore.kernel.org/r/20191114200147.1073-1-dmonakhov@gmail.comSigned-off-by: Theodore Ts'o <tytso@mit.edu>

include/trace/events/ext4.h

@@ -48,6 +48,16 @@ struct partial_cluster;
 	{ EXT4_GET_BLOCKS_KEEP_SIZE,		"KEEP_SIZE" },		\
 	{ EXT4_GET_BLOCKS_ZERO,			"ZERO" })
 
+/*
+ * __print_flags() requires that all enum values be wrapped in the
+ * TRACE_DEFINE_ENUM macro so that the enum value can be encoded in the ftrace
+ * ring buffer.
+ */
+TRACE_DEFINE_ENUM(BH_New);
+TRACE_DEFINE_ENUM(BH_Mapped);
+TRACE_DEFINE_ENUM(BH_Unwritten);
+TRACE_DEFINE_ENUM(BH_Boundary);
+
 #define show_mflags(flags) __print_flags(flags, "",	\
 	{ EXT4_MAP_NEW,		"N" },			\
 	{ EXT4_MAP_MAPPED,	"M" },			\
@@ -62,11 +72,18 @@ struct partial_cluster;
 	{ EXT4_FREE_BLOCKS_NOFREE_FIRST_CLUSTER,"1ST_CLUSTER" },\
 	{ EXT4_FREE_BLOCKS_NOFREE_LAST_CLUSTER,	"LAST_CLUSTER" })
 
+TRACE_DEFINE_ENUM(ES_WRITTEN_B);
+TRACE_DEFINE_ENUM(ES_UNWRITTEN_B);
+TRACE_DEFINE_ENUM(ES_DELAYED_B);
+TRACE_DEFINE_ENUM(ES_HOLE_B);
+TRACE_DEFINE_ENUM(ES_REFERENCED_B);
+
 #define show_extent_status(status) __print_flags(status, "",	\
 	{ EXTENT_STATUS_WRITTEN,	"W" },			\
 	{ EXTENT_STATUS_UNWRITTEN,	"U" },			\
 	{ EXTENT_STATUS_DELAYED,	"D" },			\
-	{ EXTENT_STATUS_HOLE,		"H" })
+	{ EXTENT_STATUS_HOLE,		"H" },			\
+	{ EXTENT_STATUS_REFERENCED,	"R" })
 
 #define show_falloc_mode(mode) __print_flags(mode, "|",		\
 	{ FALLOC_FL_KEEP_SIZE,		"KEEP_SIZE"},		\