Add inital extents read-write support.

Approved by:    pfg (mentor)
MFC after:      6 months
RelNotes:       Yes

Differential Revision:    https://reviews.freebsd.org/D12087

1 files changed, 31 insertions, 9 deletions

diff --git a/sys/fs/ext2fs/ext2_extents.h b/sys/fs/ext2fs/ext2_extents.h
index 91cb0d32346c..b69da4cdba19 100644
--- a/sys/fs/ext2fs/ext2_extents.h
+++ b/sys/fs/ext2fs/ext2_extents.h
@@ -31,6 +31,10 @@
 #include <sys/types.h>
 
 #define	EXT4_EXT_MAGIC  0xf30a
+#define EXT4_MAX_BLOCKS 0xffffffff
+#define EXT_INIT_MAX_LEN (1UL << 15)
+#define EXT4_MAX_LEN	(EXT_INIT_MAX_LEN - 1)
+#define EXT4_EXT_DEPTH_MAX 5
 
 #define	EXT4_EXT_CACHE_NO	0
 #define	EXT4_EXT_CACHE_GAP	1
@@ -82,23 +86,41 @@ struct ext4_extent_cache {
  * Save path to some extent.
  */
 struct ext4_extent_path {
+	int index_count;
 	uint16_t ep_depth;
-	struct buf *ep_bp;
-	bool	ep_is_sparse;
-	union {
-		struct ext4_extent ep_sparse_ext;
-		struct ext4_extent *ep_ext;
-	};
+	uint64_t ep_blk;
+	char *ep_data;
+	struct ext4_extent *ep_ext;
 	struct ext4_extent_index *ep_index;
 	struct ext4_extent_header *ep_header;
 };
 
+#define EXT_FIRST_EXTENT(hdr) ((struct ext4_extent *)(((char *)(hdr)) + \
+    sizeof(struct ext4_extent_header)))
+#define EXT_FIRST_INDEX(hdr) ((struct ext4_extent_index *)(((char *)(hdr)) + \
+    sizeof(struct ext4_extent_header)))
+#define EXT_LAST_EXTENT(hdr) (EXT_FIRST_EXTENT((hdr)) + (hdr)->eh_ecount - 1)
+#define EXT_LAST_INDEX(hdr) (EXT_FIRST_INDEX((hdr)) + (hdr)->eh_ecount - 1)
+#define EXT4_EXTENT_TAIL_OFFSET(hdr) (sizeof(struct ext4_extent_header) + \
+    (sizeof(struct ext4_extent) * (hdr)->eh_max))
+#define EXT_HAS_FREE_INDEX(path) \
+    ((path)->ep_header->eh_ecount < (path)->ep_header->eh_max)
+#define EXT_MAX_EXTENT(hdr) (EXT_FIRST_EXTENT(hdr) + ((hdr)->eh_max) - 1)
+#define EXT_MAX_INDEX(hdr) (EXT_FIRST_INDEX((hdr)) + (hdr)->eh_max - 1)
+
 struct inode;
 struct m_ext2fs;
+void	ext4_ext_tree_init(struct inode *ip);
 int	ext4_ext_in_cache(struct inode *, daddr_t, struct ext4_extent *);
 void	ext4_ext_put_cache(struct inode *, struct ext4_extent *, int);
-struct ext4_extent_path *
-ext4_ext_find_extent(struct m_ext2fs *fs,
-    struct inode *, daddr_t, struct ext4_extent_path *);
+int ext4_ext_find_extent(struct inode *, daddr_t, struct ext4_extent_path **);
+void ext4_ext_path_free(struct ext4_extent_path *path);
+int ext4_ext_remove_space(struct inode *ip, off_t length, int flags,
+    struct ucred *cred, struct thread *td);
+int ext4_ext_get_blocks(struct inode *ip, int64_t iblock,
+    unsigned long max_blocks, struct ucred *cred, struct buf **bpp, int *allocate, uint32_t *);
+#ifdef EXT2FS_DEBUG
+void ext4_ext_print_extent_tree_status(struct inode * ip);
+#endif
 
 #endif	/* !_FS_EXT2FS_EXT2_EXTENTS_H_ */