text: // SPDX-License-Identifier: GPL-2.0
  /*
   * Copyright (c) 2000-2003,2005 Silicon Graphics, Inc.
   * All Rights Reserved.
   */
  #ifndef	__XFS_INODE_FORK_H__
  #define	__XFS_INODE_FORK_H__
  
  struct xfs_inode_log_item;
  struct xfs_dinode;
  
  /*
   * File incore extent information, present for each of data & attr forks.
   */
  struct xfs_ifork {
  	int64_t			if_bytes;	/* bytes in if_u1 */
  	struct xfs_btree_block	*if_broot;	/* file's incore btree root */
  	unsigned int		if_seq;		/* fork mod counter */
  	int			if_height;	/* height of the extent tree */
  	union {
  		void		*if_root;	/* extent tree root */
  		char		*if_data;	/* inline file data */
  	} if_u1;
  	short			if_broot_bytes;	/* bytes allocated for root */
  	unsigned char		if_flags;	/* per-fork flags */
  };
  
  /*
   * Per-fork incore inode flags.
   */
  #define	XFS_IFINLINE	0x01	/* Inline data is read in */
  #define	XFS_IFEXTENTS	0x02	/* All extent pointers are read in */
  #define	XFS_IFBROOT	0x04	/* i_broot points to the bmap b-tree root */
  
  /*
   * Fork handling.
   */
  
  #define XFS_IFORK_Q(ip)			((ip)->i_d.di_forkoff != 0)
  #define XFS_IFORK_BOFF(ip)		((int)((ip)->i_d.di_forkoff << 3))
  
  #define XFS_IFORK_PTR(ip,w)		\
  	((w) == XFS_DATA_FORK ? \
  		&(ip)->i_df : \
  		((w) == XFS_ATTR_FORK ? \
  			(ip)->i_afp : \
  			(ip)->i_cowfp))
  #define XFS_IFORK_DSIZE(ip) \
  	(XFS_IFORK_Q(ip) ? XFS_IFORK_BOFF(ip) : XFS_LITINO((ip)->i_mount))
  #define XFS_IFORK_ASIZE(ip) \
  	(XFS_IFORK_Q(ip) ? XFS_LITINO((ip)->i_mount) - XFS_IFORK_BOFF(ip) : 0)
  #define XFS_IFORK_SIZE(ip,w) \
  	((w) == XFS_DATA_FORK ? \
  		XFS_IFORK_DSIZE(ip) : \
  		((w) == XFS_ATTR_FORK ? \
  			XFS_IFORK_ASIZE(ip) : \
  			0))
  #define XFS_IFORK_FORMAT(ip,w) \
  	((w) == XFS_DATA_FORK ? \
  		(ip)->i_d.di_format : \
  		((w) == XFS_ATTR_FORK ? \
  			(ip)->i_d.di_aformat : \
  			(ip)->i_cformat))
  #define XFS_IFORK_FMT_SET(ip,w,n) \
  	((w) == XFS_DATA_FORK ? \
  		((ip)->i_d.di_format = (n)) : \
  		((w) == XFS_ATTR_FORK ? \
  			((ip)->i_d.di_aformat = (n)) : \
  			((ip)->i_cformat = (n))))
  #define XFS_IFORK_NEXTENTS(ip,w) \
  	((w) == XFS_DATA_FORK ? \
  		(ip)->i_d.di_nextents : \
  		((w) == XFS_ATTR_FORK ? \
  			(ip)->i_d.di_anextents : \
  			(ip)->i_cnextents))
  #define XFS_IFORK_NEXT_SET(ip,w,n) \
  	((w) == XFS_DATA_FORK ? \
  		((ip)->i_d.di_nextents = (n)) : \
  		((w) == XFS_ATTR_FORK ? \
  			((ip)->i_d.di_anextents = (n)) : \
  			((ip)->i_cnextents = (n))))
  #define XFS_IFORK_MAXEXT(ip, w) \
  	(XFS_IFORK_SIZE(ip, w) / sizeof(xfs_bmbt_rec_t))
  
  #define xfs_ifork_has_extents(ip, w) \
  	(XFS_IFORK_FORMAT((ip), (w)) == XFS_DINODE_FMT_EXTENTS || \
  	 XFS_IFORK_FORMAT((ip), (w)) == XFS_DINODE_FMT_BTREE)
  
  struct xfs_ifork *xfs_iext_state_to_fork(struct xfs_inode *ip, int state);
  
  int		xfs_iformat_fork(struct xfs_inode *, struct xfs_dinode *);
  void		xfs_iflush_fork(struct xfs_inode *, struct xfs_dinode *,
  				struct xfs_inode_log_item *, int);
  void		xfs_idestroy_fork(struct xfs_inode *, int);
  void		xfs_idata_realloc(struct xfs_inode *ip, int64_t byte_diff,
  				int whichfork);
  void		xfs_iroot_realloc(struct xfs_inode *, int, int);
  int		xfs_iread_extents(struct xfs_trans *, struct xfs_inode *, int);
  int		xfs_iextents_copy(struct xfs_inode *, struct xfs_bmbt_rec *,
  				  int);
  void		xfs_init_local_fork(struct xfs_inode *ip, int whichfork,
  				const void *data, int64_t size);
  
  xfs_extnum_t	xfs_iext_count(struct xfs_ifork *ifp);
  void		xfs_iext_insert(struct xfs_inode *, struct xfs_iext_cursor *cur,
  			struct xfs_bmbt_irec *, int);
  void		xfs_iext_remove(struct xfs_inode *, struct xfs_iext_cursor *,
  			int);
  void		xfs_iext_destroy(struct xfs_ifork *);
  
  bool		xfs_iext_lookup_extent(struct xfs_inode *ip,
  			struct xfs_ifork *ifp, xfs_fileoff_t bno,
  			struct xfs_iext_cursor *cur,
  			struct xfs_bmbt_irec *gotp);
  bool		xfs_iext_lookup_extent_before(struct xfs_inode *ip,
  			struct xfs_ifork *ifp, xfs_fileoff_t *end,
  			struct xfs_iext_cursor *cur,
  			struct xfs_bmbt_irec *gotp);
  bool		xfs_iext_get_extent(struct xfs_ifork *ifp,
  			struct xfs_iext_cursor *cur,
  			struct xfs_bmbt_irec *gotp);
  void		xfs_iext_update_extent(struct xfs_inode *ip, int state,
  			struct xfs_iext_cursor *cur,
  			struct xfs_bmbt_irec *gotp);
  
  void		xfs_iext_first(struct xfs_ifork *, struct xfs_iext_cursor *);
  void		xfs_iext_last(struct xfs_ifork *, struct xfs_iext_cursor *);
  void		xfs_iext_next(struct xfs_ifork *, struct xfs_iext_cursor *);
  void		xfs_iext_prev(struct xfs_ifork *, struct xfs_iext_cursor *);
  
  static inline bool xfs_iext_next_extent(struct xfs_ifork *ifp,
  		struct xfs_iext_cursor *cur, struct xfs_bmbt_irec *gotp)
  {
  	xfs_iext_next(ifp, cur);
  	return xfs_iext_get_extent(ifp, cur, gotp);
  }
  
  static inline bool xfs_iext_prev_extent(struct xfs_ifork *ifp,
  		struct xfs_iext_cursor *cur, struct xfs_bmbt_irec *gotp)
  {
  	xfs_iext_prev(ifp, cur);
  	return xfs_iext_get_extent(ifp, cur, gotp);
  }
  
  /*
   * Return the extent after cur in gotp without updating the cursor.
   */
  static inline bool xfs_iext_peek_next_extent(struct xfs_ifork *ifp,
  		struct xfs_iext_cursor *cur, struct xfs_bmbt_irec *gotp)
  {
  	struct xfs_iext_cursor ncur = *cur;
  
  	xfs_iext_next(ifp, &ncur);
  	return xfs_iext_get_extent(ifp, &ncur, gotp);
  }
  
  /*
   * Return the extent before cur in gotp without updating the cursor.
   */
  static inline bool xfs_iext_peek_prev_extent(struct xfs_ifork *ifp,
  		struct xfs_iext_cursor *cur, struct xfs_bmbt_irec *gotp)
  {
  	struct xfs_iext_cursor ncur = *cur;
  
  	xfs_iext_prev(ifp, &ncur);
  	return xfs_iext_get_extent(ifp, &ncur, gotp);
  }
  
  #define for_each_xfs_iext(ifp, ext, got)		\
  	for (xfs_iext_first((ifp), (ext));		\
  	     xfs_iext_get_extent((ifp), (ext), (got));	\
  	     xfs_iext_next((ifp), (ext)))
  
  extern struct kmem_zone	*xfs_ifork_zone;
  
  extern void xfs_ifork_init_cow(struct xfs_inode *ip);
  
  typedef xfs_failaddr_t (*xfs_ifork_verifier_t)(struct xfs_inode *);
  
  struct xfs_ifork_ops {
  	xfs_ifork_verifier_t	verify_symlink;
  	xfs_ifork_verifier_t	verify_dir;
  	xfs_ifork_verifier_t	verify_attr;
  };
  extern struct xfs_ifork_ops	xfs_default_ifork_ops;
  
  xfs_failaddr_t xfs_ifork_verify_data(struct xfs_inode *ip,
  		struct xfs_ifork_ops *ops);
  xfs_failaddr_t xfs_ifork_verify_attr(struct xfs_inode *ip,
  		struct xfs_ifork_ops *ops);
  
  #endif	/* __XFS_INODE_FORK_H__ */
  