ext4: add physical block and status member into extent status tree

This commit adds two members in extent_status structure to let it record
physical block and extent status.  Here es_pblk is used to record both
of them because physical block only has 48 bits.  So extent status could
be stashed into it so that we can save some memory.  Now written,
unwritten, delayed and hole are defined as status.

Due to new member is added into extent status tree, all interfaces need
to be adjusted.

Signed-off-by: Zheng Liu <wenqing.lz@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
diff --git a/fs/ext4/extents_status.h b/fs/ext4/extents_status.h
index 81e9339..3cad833 100644
--- a/fs/ext4/extents_status.h
+++ b/fs/ext4/extents_status.h
@@ -20,10 +20,21 @@
 #define es_debug(fmt, ...)	no_printk(fmt, ##__VA_ARGS__)
 #endif
 
+#define EXTENT_STATUS_WRITTEN	0x80000000	/* written extent */
+#define EXTENT_STATUS_UNWRITTEN	0x40000000	/* unwritten extent */
+#define EXTENT_STATUS_DELAYED	0x20000000	/* delayed extent */
+#define EXTENT_STATUS_HOLE	0x10000000	/* hole */
+
+#define EXTENT_STATUS_FLAGS	(EXTENT_STATUS_WRITTEN | \
+				 EXTENT_STATUS_UNWRITTEN | \
+				 EXTENT_STATUS_DELAYED | \
+				 EXTENT_STATUS_HOLE)
+
 struct extent_status {
 	struct rb_node rb_node;
 	ext4_lblk_t es_lblk;	/* first logical block extent covers */
 	ext4_lblk_t es_len;	/* length of extent in block */
+	ext4_fsblk_t es_pblk;	/* first physical block */
 };
 
 struct ext4_es_tree {
@@ -36,10 +47,61 @@
 extern void ext4_es_init_tree(struct ext4_es_tree *tree);
 
 extern int ext4_es_insert_extent(struct inode *inode, ext4_lblk_t lblk,
-				 ext4_lblk_t len);
+				 ext4_lblk_t len, ext4_fsblk_t pblk,
+				 unsigned long long status);
 extern int ext4_es_remove_extent(struct inode *inode, ext4_lblk_t lblk,
 				 ext4_lblk_t len);
 extern ext4_lblk_t ext4_es_find_extent(struct inode *inode,
 				struct extent_status *es);
 
+static inline int ext4_es_is_written(struct extent_status *es)
+{
+	return (es->es_pblk & EXTENT_STATUS_WRITTEN);
+}
+
+static inline int ext4_es_is_unwritten(struct extent_status *es)
+{
+	return (es->es_pblk & EXTENT_STATUS_UNWRITTEN);
+}
+
+static inline int ext4_es_is_delayed(struct extent_status *es)
+{
+	return (es->es_pblk & EXTENT_STATUS_DELAYED);
+}
+
+static inline int ext4_es_is_hole(struct extent_status *es)
+{
+	return (es->es_pblk & EXTENT_STATUS_HOLE);
+}
+
+static inline ext4_fsblk_t ext4_es_status(struct extent_status *es)
+{
+	return (es->es_pblk & EXTENT_STATUS_FLAGS);
+}
+
+static inline ext4_fsblk_t ext4_es_pblock(struct extent_status *es)
+{
+	return (es->es_pblk & ~EXTENT_STATUS_FLAGS);
+}
+
+static inline void ext4_es_store_pblock(struct extent_status *es,
+					ext4_fsblk_t pb)
+{
+	ext4_fsblk_t block;
+
+	block = (pb & ~EXTENT_STATUS_FLAGS) |
+		(es->es_pblk & EXTENT_STATUS_FLAGS);
+	es->es_pblk = block;
+}
+
+static inline void ext4_es_store_status(struct extent_status *es,
+					unsigned long long status)
+{
+	ext4_fsblk_t block;
+
+	block = (status & EXTENT_STATUS_FLAGS) |
+		(es->es_pblk & ~EXTENT_STATUS_FLAGS);
+	es->es_pblk = block;
+}
+
 #endif /* _EXT4_EXTENTS_STATUS_H */