fs/xfs/xfs_bmap.h - kernel/msm-4.19 - Gitiles

 /*
  * Copyright (c) 2000-2006 Silicon Graphics, Inc.
  * All Rights Reserved.
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License as
  * published by the Free Software Foundation.
  *
  * This program is distributed in the hope that it would be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
  * along with this program; if not, write the Free Software Foundation,
  * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  */
 #ifndef __XFS_BMAP_H__
 #define	__XFS_BMAP_H__

 struct getbmap;
 struct xfs_bmbt_irec;
 struct xfs_ifork;
 struct xfs_inode;
 struct xfs_mount;
 struct xfs_trans;

 extern kmem_zone_t	*xfs_bmap_free_item_zone;

 /*
  * List of extents to be free "later".
  * The list is kept sorted on xbf_startblock.
  */
 typedef struct xfs_bmap_free_item
 {
 	xfs_fsblock_t		xbfi_startblock;/* starting fs block number */
 	xfs_extlen_t		xbfi_blockcount;/* number of blocks in extent */
 	struct xfs_bmap_free_item *xbfi_next;	/* link to next entry */
 } xfs_bmap_free_item_t;

 /*
  * Header for free extent list.
  *
  * xbf_low is used by the allocator to activate the lowspace algorithm -
  * when free space is running low the extent allocator may choose to
  * allocate an extent from an AG without leaving sufficient space for
  * a btree split when inserting the new extent.  In this case the allocator
  * will enable the lowspace algorithm which is supposed to allow further
  * allocations (such as btree splits and newroots) to allocate from
  * sequential AGs.  In order to avoid locking AGs out of order the lowspace
  * algorithm will start searching for free space from AG 0.  If the correct
  * transaction reservations have been made then this algorithm will eventually
  * find all the space it needs.
  */
 typedef	struct xfs_bmap_free
 {
 	xfs_bmap_free_item_t	*xbf_first;	/* list of to-be-free extents */
 	int			xbf_count;	/* count of items on list */
 	int			xbf_low;	/* alloc in low mode */
 } xfs_bmap_free_t;

 #define	XFS_BMAP_MAX_NMAP	4

 /*
  * Flags for xfs_bmapi_*
  */
 #define XFS_BMAPI_ENTIRE	0x001	/* return entire extent, not trimmed */
 #define XFS_BMAPI_METADATA	0x002	/* mapping metadata not user data */
 #define XFS_BMAPI_ATTRFORK	0x004	/* use attribute fork not data */
 #define XFS_BMAPI_PREALLOC	0x008	/* preallocation op: unwritten space */
 #define XFS_BMAPI_IGSTATE	0x010	/* Ignore state - */
 					/* combine contig. space */
 #define XFS_BMAPI_CONTIG	0x020	/* must allocate only one extent */
 /*
  * unwritten extent conversion - this needs write cache flushing and no additional
  * allocation alignments. When specified with XFS_BMAPI_PREALLOC it converts
  * from written to unwritten, otherwise convert from unwritten to written.
  */
 #define XFS_BMAPI_CONVERT	0x040

 #define XFS_BMAPI_FLAGS \
 	{ XFS_BMAPI_ENTIRE,	"ENTIRE" }, \
 	{ XFS_BMAPI_METADATA,	"METADATA" }, \
 	{ XFS_BMAPI_ATTRFORK,	"ATTRFORK" }, \
 	{ XFS_BMAPI_PREALLOC,	"PREALLOC" }, \
 	{ XFS_BMAPI_IGSTATE,	"IGSTATE" }, \
 	{ XFS_BMAPI_CONTIG,	"CONTIG" }, \
 	{ XFS_BMAPI_CONVERT,	"CONVERT" }


 static inline int xfs_bmapi_aflag(int w)
 {
 	return (w == XFS_ATTR_FORK ? XFS_BMAPI_ATTRFORK : 0);
 }

 /*
  * Special values for xfs_bmbt_irec_t br_startblock field.
  */
 #define	DELAYSTARTBLOCK		((xfs_fsblock_t)-1LL)
 #define	HOLESTARTBLOCK		((xfs_fsblock_t)-2LL)

 static inline void xfs_bmap_init(xfs_bmap_free_t *flp, xfs_fsblock_t *fbp)
 {
 	((flp)->xbf_first = NULL, (flp)->xbf_count = 0, \
 		(flp)->xbf_low = 0, *(fbp) = NULLFSBLOCK);
 }

 /*
  * Argument structure for xfs_bmap_alloc.
  */
 typedef struct xfs_bmalloca {
 	xfs_fsblock_t		*firstblock; /* i/o first block allocated */
 	struct xfs_bmap_free	*flist;	/* bmap freelist */
 	struct xfs_trans	*tp;	/* transaction pointer */
 	struct xfs_inode	*ip;	/* incore inode pointer */
 	struct xfs_bmbt_irec	prev;	/* extent before the new one */
 	struct xfs_bmbt_irec	got;	/* extent after, or delayed */

 	xfs_fileoff_t		offset;	/* offset in file filling in */
 	xfs_extlen_t		length;	/* i/o length asked/allocated */
 	xfs_fsblock_t		blkno;	/* starting block of new extent */

 	xfs_extlen_t		total;	/* total blocks needed for xaction */
 	xfs_extlen_t		minlen;	/* minimum allocation size (blocks) */
 	xfs_extlen_t		minleft; /* amount must be left after alloc */
 	char			eof;	/* set if allocating past last extent */
 	char			wasdel;	/* replacing a delayed allocation */
 	char			userdata;/* set if is user data */
 	char			aeof;	/* allocated space at eof */
 	char			conv;	/* overwriting unwritten extents */
 } xfs_bmalloca_t;

 /*
  * Flags for xfs_bmap_add_extent*.
  */
 #define BMAP_LEFT_CONTIG	(1 << 0)
 #define BMAP_RIGHT_CONTIG	(1 << 1)
 #define BMAP_LEFT_FILLING	(1 << 2)
 #define BMAP_RIGHT_FILLING	(1 << 3)
 #define BMAP_LEFT_DELAY		(1 << 4)
 #define BMAP_RIGHT_DELAY	(1 << 5)
 #define BMAP_LEFT_VALID		(1 << 6)
 #define BMAP_RIGHT_VALID	(1 << 7)
 #define BMAP_ATTRFORK		(1 << 8)

 #define XFS_BMAP_EXT_FLAGS \
 	{ BMAP_LEFT_CONTIG,	"LC" }, \
 	{ BMAP_RIGHT_CONTIG,	"RC" }, \
 	{ BMAP_LEFT_FILLING,	"LF" }, \
 	{ BMAP_RIGHT_FILLING,	"RF" }, \
 	{ BMAP_ATTRFORK,	"ATTR" }

 /*
  * Add bmap trace insert entries for all the contents of the extent list.
  *
  * Quite excessive tracing.  Only do this for debug builds.
  */
 #if defined(__KERNEL) && defined(DEBUG)
 void
 xfs_bmap_trace_exlist(
 	struct xfs_inode	*ip,		/* incore inode pointer */
 	xfs_extnum_t		cnt,		/* count of entries in list */
 	int			whichfork,
 	unsigned long		caller_ip);	/* data or attr fork */
 #define	XFS_BMAP_TRACE_EXLIST(ip,c,w)	\
 	xfs_bmap_trace_exlist(ip,c,w, _THIS_IP_)
 #else
 #define	XFS_BMAP_TRACE_EXLIST(ip,c,w)
 #endif

 /*
  * Convert inode from non-attributed to attributed.
  * Must not be in a transaction, ip must not be locked.
  */
 int					/* error code */
 xfs_bmap_add_attrfork(
 	struct xfs_inode	*ip,	/* incore inode pointer */
 	int			size,	/* space needed for new attribute */
 	int			rsvd);	/* flag for reserved block allocation */

 /*
  * Add the extent to the list of extents to be free at transaction end.
  * The list is maintained sorted (by block number).
  */
 void
 xfs_bmap_add_free(
 	xfs_fsblock_t		bno,		/* fs block number of extent */
 	xfs_filblks_t		len,		/* length of extent */
 	xfs_bmap_free_t		*flist,		/* list of extents */
 	struct xfs_mount	*mp);		/* mount point structure */

 /*
  * Routine to clean up the free list data structure when
  * an error occurs during a transaction.
  */
 void
 xfs_bmap_cancel(
 	xfs_bmap_free_t		*flist);	/* free list to clean up */

 /*
  * Compute and fill in the value of the maximum depth of a bmap btree
  * in this filesystem.  Done once, during mount.
  */
 void
 xfs_bmap_compute_maxlevels(
 	struct xfs_mount	*mp,	/* file system mount structure */
 	int			whichfork);	/* data or attr fork */

 /*
  * Returns the file-relative block number of the first unused block in the file.
  * This is the lowest-address hole if the file has holes, else the first block
  * past the end of file.
  */
 int						/* error */
 xfs_bmap_first_unused(
 	struct xfs_trans	*tp,		/* transaction pointer */
 	struct xfs_inode	*ip,		/* incore inode */
 	xfs_extlen_t		len,		/* size of hole to find */
 	xfs_fileoff_t		*unused,	/* unused block num */
 	int			whichfork);	/* data or attr fork */

 /*
  * Returns the file-relative block number of the last block + 1 before
  * last_block (input value) in the file.
  * This is not based on i_size, it is based on the extent list.
  * Returns 0 for local files, as they do not have an extent list.
  */
 int						/* error */
 xfs_bmap_last_before(
 	struct xfs_trans	*tp,		/* transaction pointer */
 	struct xfs_inode	*ip,		/* incore inode */
 	xfs_fileoff_t		*last_block,	/* last block */
 	int			whichfork);	/* data or attr fork */

 /*
  * Returns the file-relative block number of the first block past eof in
  * the file.  This is not based on i_size, it is based on the extent list.
  * Returns 0 for local files, as they do not have an extent list.
  */
 int						/* error */
 xfs_bmap_last_offset(
 	struct xfs_trans	*tp,		/* transaction pointer */
 	struct xfs_inode	*ip,		/* incore inode */
 	xfs_fileoff_t		*unused,	/* last block num */
 	int			whichfork);	/* data or attr fork */

 /*
  * Returns whether the selected fork of the inode has exactly one
  * block or not.  For the data fork we check this matches di_size,
  * implying the file's range is 0..bsize-1.
  */
 int
 xfs_bmap_one_block(
 	struct xfs_inode	*ip,		/* incore inode */
 	int			whichfork);	/* data or attr fork */

 /*
  * Read in the extents to iu_extents.
  * All inode fields are set up by caller, we just traverse the btree
  * and copy the records in.
  */
 int						/* error */
 xfs_bmap_read_extents(
 	struct xfs_trans	*tp,		/* transaction pointer */
 	struct xfs_inode	*ip,		/* incore inode */
 	int			whichfork);	/* data or attr fork */

 int	xfs_bmapi_read(struct xfs_inode *ip, xfs_fileoff_t bno,
 		xfs_filblks_t len, struct xfs_bmbt_irec *mval,
 		int *nmap, int flags);
 int	xfs_bmapi_delay(struct xfs_inode *ip, xfs_fileoff_t bno,
 		xfs_filblks_t len, struct xfs_bmbt_irec *mval,
 		int *nmap, int flags);
 int	xfs_bmapi_write(struct xfs_trans *tp, struct xfs_inode *ip,
 		xfs_fileoff_t bno, xfs_filblks_t len, int flags,
 		xfs_fsblock_t *firstblock, xfs_extlen_t total,
 		struct xfs_bmbt_irec *mval, int *nmap,
 		struct xfs_bmap_free *flist);

 /*
  * Unmap (remove) blocks from a file.
  * If nexts is nonzero then the number of extents to remove is limited to
  * that value.  If not all extents in the block range can be removed then
  * *done is set.
  */
 int						/* error */
 xfs_bunmapi(
 	struct xfs_trans	*tp,		/* transaction pointer */
 	struct xfs_inode	*ip,		/* incore inode */
 	xfs_fileoff_t		bno,		/* starting offset to unmap */
 	xfs_filblks_t		len,		/* length to unmap in file */
 	int			flags,		/* XFS_BMAPI_... */
 	xfs_extnum_t		nexts,		/* number of extents max */
 	xfs_fsblock_t		*firstblock,	/* first allocated block
 						   controls a.g. for allocs */
 	xfs_bmap_free_t		*flist,		/* i/o: list extents to free */
 	int			*done);		/* set if not done yet */

 /*
  * Check an extent list, which has just been read, for
  * any bit in the extent flag field.
  */
 int
 xfs_check_nostate_extents(
 	struct xfs_ifork	*ifp,
 	xfs_extnum_t		idx,
 	xfs_extnum_t		num);

 uint
 xfs_default_attroffset(
 	struct xfs_inode	*ip);

 #ifdef __KERNEL__

 /*
  * Routine to be called at transaction's end by xfs_bmapi, xfs_bunmapi
  * caller.  Frees all the extents that need freeing, which must be done
  * last due to locking considerations.
  *
  * Return 1 if the given transaction was committed and a new one allocated,
  * and 0 otherwise.
  */
 int						/* error */
 xfs_bmap_finish(
 	struct xfs_trans	**tp,		/* transaction pointer addr */
 	xfs_bmap_free_t		*flist,		/* i/o: list extents to free */
 	int			*committed);	/* xact committed or not */

 /* bmap to userspace formatter - copy to user & advance pointer */
 typedef int (*xfs_bmap_format_t)(void **, struct getbmapx *, int *);

 /*
  * Get inode's extents as described in bmv, and format for output.
  */
 int						/* error code */
 xfs_getbmap(
 	xfs_inode_t		*ip,
 	struct getbmapx		*bmv,		/* user bmap structure */
 	xfs_bmap_format_t	formatter,	/* format to user */
 	void			*arg);		/* formatter arg */

 /*
  * Check if the endoff is outside the last extent. If so the caller will grow
  * the allocation to a stripe unit boundary
  */
 int
 xfs_bmap_eof(
 	struct xfs_inode        *ip,
 	xfs_fileoff_t           endoff,
 	int                     whichfork,
 	int                     *eof);

 /*
  * Count fsblocks of the given fork.
  */
 int
 xfs_bmap_count_blocks(
 	xfs_trans_t		*tp,
 	struct xfs_inode	*ip,
 	int			whichfork,
 	int			*count);

 int
 xfs_bmap_punch_delalloc_range(
 	struct xfs_inode	*ip,
 	xfs_fileoff_t		start_fsb,
 	xfs_fileoff_t		length);
 #endif	/* __KERNEL__ */

 #endif	/* __XFS_BMAP_H__ */
	/*
	* Copyright (c) 2000-2006 Silicon Graphics, Inc.
	* All Rights Reserved.
	*
	* This program is free software; you can redistribute it and/or
	* modify it under the terms of the GNU General Public License as
	* published by the Free Software Foundation.
	*
	* This program is distributed in the hope that it would be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	* GNU General Public License for more details.
	*
	* You should have received a copy of the GNU General Public License
	* along with this program; if not, write the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
	*/
	#ifndef __XFS_BMAP_H__
	#define __XFS_BMAP_H__

	struct getbmap;
	struct xfs_bmbt_irec;
	struct xfs_ifork;
	struct xfs_inode;
	struct xfs_mount;
	struct xfs_trans;

	extern kmem_zone_t *xfs_bmap_free_item_zone;

	/*
	* List of extents to be free "later".
	* The list is kept sorted on xbf_startblock.
	*/
	typedef struct xfs_bmap_free_item
	{
	xfs_fsblock_t xbfi_startblock;/* starting fs block number */
	xfs_extlen_t xbfi_blockcount;/* number of blocks in extent */
	struct xfs_bmap_free_item xbfi_next; / link to next entry */
	} xfs_bmap_free_item_t;

	/*
	* Header for free extent list.
	*
	* xbf_low is used by the allocator to activate the lowspace algorithm -
	* when free space is running low the extent allocator may choose to
	* allocate an extent from an AG without leaving sufficient space for
	* a btree split when inserting the new extent. In this case the allocator
	* will enable the lowspace algorithm which is supposed to allow further
	* allocations (such as btree splits and newroots) to allocate from
	* sequential AGs. In order to avoid locking AGs out of order the lowspace
	* algorithm will start searching for free space from AG 0. If the correct
	* transaction reservations have been made then this algorithm will eventually
	* find all the space it needs.
	*/
	typedef struct xfs_bmap_free
	{
	xfs_bmap_free_item_t xbf_first; / list of to-be-free extents */
	int xbf_count; /* count of items on list */
	int xbf_low; /* alloc in low mode */
	} xfs_bmap_free_t;

	#define XFS_BMAP_MAX_NMAP 4

	/*
	* Flags for xfs_bmapi_*
	*/
	#define XFS_BMAPI_ENTIRE 0x001 /* return entire extent, not trimmed */
	#define XFS_BMAPI_METADATA 0x002 /* mapping metadata not user data */
	#define XFS_BMAPI_ATTRFORK 0x004 /* use attribute fork not data */
	#define XFS_BMAPI_PREALLOC 0x008 /* preallocation op: unwritten space */
	#define XFS_BMAPI_IGSTATE 0x010 /* Ignore state - */
	/* combine contig. space */
	#define XFS_BMAPI_CONTIG 0x020 /* must allocate only one extent */
	/*
	* unwritten extent conversion - this needs write cache flushing and no additional
	* allocation alignments. When specified with XFS_BMAPI_PREALLOC it converts
	* from written to unwritten, otherwise convert from unwritten to written.
	*/
	#define XFS_BMAPI_CONVERT 0x040

	#define XFS_BMAPI_FLAGS \
	{ XFS_BMAPI_ENTIRE, "ENTIRE" }, \
	{ XFS_BMAPI_METADATA, "METADATA" }, \
	{ XFS_BMAPI_ATTRFORK, "ATTRFORK" }, \
	{ XFS_BMAPI_PREALLOC, "PREALLOC" }, \
	{ XFS_BMAPI_IGSTATE, "IGSTATE" }, \
	{ XFS_BMAPI_CONTIG, "CONTIG" }, \
	{ XFS_BMAPI_CONVERT, "CONVERT" }


	static inline int xfs_bmapi_aflag(int w)
	{
	return (w == XFS_ATTR_FORK ? XFS_BMAPI_ATTRFORK : 0);
	}

	/*
	* Special values for xfs_bmbt_irec_t br_startblock field.
	*/
	#define DELAYSTARTBLOCK ((xfs_fsblock_t)-1LL)
	#define HOLESTARTBLOCK ((xfs_fsblock_t)-2LL)

	static inline void xfs_bmap_init(xfs_bmap_free_t flp, xfs_fsblock_t fbp)
	{
	((flp)->xbf_first = NULL, (flp)->xbf_count = 0, \
	(flp)->xbf_low = 0, *(fbp) = NULLFSBLOCK);
	}

	/*
	* Argument structure for xfs_bmap_alloc.
	*/
	typedef struct xfs_bmalloca {
	xfs_fsblock_t firstblock; / i/o first block allocated */
	struct xfs_bmap_free flist; / bmap freelist */
	struct xfs_trans tp; / transaction pointer */
	struct xfs_inode ip; / incore inode pointer */
	struct xfs_bmbt_irec prev; /* extent before the new one */
	struct xfs_bmbt_irec got; /* extent after, or delayed */

	xfs_fileoff_t offset; /* offset in file filling in */
	xfs_extlen_t length; /* i/o length asked/allocated */
	xfs_fsblock_t blkno; /* starting block of new extent */

	xfs_extlen_t total; /* total blocks needed for xaction */
	xfs_extlen_t minlen; /* minimum allocation size (blocks) */
	xfs_extlen_t minleft; /* amount must be left after alloc */
	char eof; /* set if allocating past last extent */
	char wasdel; /* replacing a delayed allocation */
	char userdata;/* set if is user data */
	char aeof; /* allocated space at eof */
	char conv; /* overwriting unwritten extents */
	} xfs_bmalloca_t;

	/*
	* Flags for xfs_bmap_add_extent*.
	*/
	#define BMAP_LEFT_CONTIG (1 << 0)
	#define BMAP_RIGHT_CONTIG (1 << 1)
	#define BMAP_LEFT_FILLING (1 << 2)
	#define BMAP_RIGHT_FILLING (1 << 3)
	#define BMAP_LEFT_DELAY (1 << 4)
	#define BMAP_RIGHT_DELAY (1 << 5)
	#define BMAP_LEFT_VALID (1 << 6)
	#define BMAP_RIGHT_VALID (1 << 7)
	#define BMAP_ATTRFORK (1 << 8)

	#define XFS_BMAP_EXT_FLAGS \
	{ BMAP_LEFT_CONTIG, "LC" }, \
	{ BMAP_RIGHT_CONTIG, "RC" }, \
	{ BMAP_LEFT_FILLING, "LF" }, \
	{ BMAP_RIGHT_FILLING, "RF" }, \
	{ BMAP_ATTRFORK, "ATTR" }

	/*
	* Add bmap trace insert entries for all the contents of the extent list.
	*
	* Quite excessive tracing. Only do this for debug builds.
	*/
	#if defined(__KERNEL) && defined(DEBUG)
	void
	xfs_bmap_trace_exlist(
	struct xfs_inode ip, / incore inode pointer */
	xfs_extnum_t cnt, /* count of entries in list */
	int whichfork,
	unsigned long caller_ip); /* data or attr fork */
	#define XFS_BMAP_TRACE_EXLIST(ip,c,w) \
	xfs_bmap_trace_exlist(ip,c,w, _THIS_IP_)
	#else
	#define XFS_BMAP_TRACE_EXLIST(ip,c,w)
	#endif

	/*
	* Convert inode from non-attributed to attributed.
	* Must not be in a transaction, ip must not be locked.
	*/
	int /* error code */
	xfs_bmap_add_attrfork(
	struct xfs_inode ip, / incore inode pointer */
	int size, /* space needed for new attribute */
	int rsvd); /* flag for reserved block allocation */

	/*
	* Add the extent to the list of extents to be free at transaction end.
	* The list is maintained sorted (by block number).
	*/
	void
	xfs_bmap_add_free(
	xfs_fsblock_t bno, /* fs block number of extent */
	xfs_filblks_t len, /* length of extent */
	xfs_bmap_free_t flist, / list of extents */
	struct xfs_mount mp); / mount point structure */

	/*
	* Routine to clean up the free list data structure when
	* an error occurs during a transaction.
	*/
	void
	xfs_bmap_cancel(
	xfs_bmap_free_t flist); / free list to clean up */

	/*
	* Compute and fill in the value of the maximum depth of a bmap btree
	* in this filesystem. Done once, during mount.
	*/
	void
	xfs_bmap_compute_maxlevels(
	struct xfs_mount mp, / file system mount structure */
	int whichfork); /* data or attr fork */

	/*
	* Returns the file-relative block number of the first unused block in the file.
	* This is the lowest-address hole if the file has holes, else the first block
	* past the end of file.
	*/
	int /* error */
	xfs_bmap_first_unused(
	struct xfs_trans tp, / transaction pointer */
	struct xfs_inode ip, / incore inode */
	xfs_extlen_t len, /* size of hole to find */
	xfs_fileoff_t unused, / unused block num */
	int whichfork); /* data or attr fork */

	/*
	* Returns the file-relative block number of the last block + 1 before
	* last_block (input value) in the file.
	* This is not based on i_size, it is based on the extent list.
	* Returns 0 for local files, as they do not have an extent list.
	*/
	int /* error */
	xfs_bmap_last_before(
	struct xfs_trans tp, / transaction pointer */
	struct xfs_inode ip, / incore inode */
	xfs_fileoff_t last_block, / last block */
	int whichfork); /* data or attr fork */

	/*
	* Returns the file-relative block number of the first block past eof in
	* the file. This is not based on i_size, it is based on the extent list.
	* Returns 0 for local files, as they do not have an extent list.
	*/
	int /* error */
	xfs_bmap_last_offset(
	struct xfs_trans tp, / transaction pointer */
	struct xfs_inode ip, / incore inode */
	xfs_fileoff_t unused, / last block num */
	int whichfork); /* data or attr fork */

	/*
	* Returns whether the selected fork of the inode has exactly one
	* block or not. For the data fork we check this matches di_size,
	* implying the file's range is 0..bsize-1.
	*/
	int
	xfs_bmap_one_block(
	struct xfs_inode ip, / incore inode */
	int whichfork); /* data or attr fork */

	/*
	* Read in the extents to iu_extents.
	* All inode fields are set up by caller, we just traverse the btree
	* and copy the records in.
	*/
	int /* error */
	xfs_bmap_read_extents(
	struct xfs_trans tp, / transaction pointer */
	struct xfs_inode ip, / incore inode */
	int whichfork); /* data or attr fork */

	int xfs_bmapi_read(struct xfs_inode *ip, xfs_fileoff_t bno,
	xfs_filblks_t len, struct xfs_bmbt_irec *mval,
	int *nmap, int flags);
	int xfs_bmapi_delay(struct xfs_inode *ip, xfs_fileoff_t bno,
	xfs_filblks_t len, struct xfs_bmbt_irec *mval,
	int *nmap, int flags);
	int xfs_bmapi_write(struct xfs_trans tp, struct xfs_inode ip,
	xfs_fileoff_t bno, xfs_filblks_t len, int flags,
	xfs_fsblock_t *firstblock, xfs_extlen_t total,
	struct xfs_bmbt_irec mval, int nmap,
	struct xfs_bmap_free *flist);

	/*
	* Unmap (remove) blocks from a file.
	* If nexts is nonzero then the number of extents to remove is limited to
	* that value. If not all extents in the block range can be removed then
	* *done is set.
	*/
	int /* error */
	xfs_bunmapi(
	struct xfs_trans tp, / transaction pointer */
	struct xfs_inode ip, / incore inode */
	xfs_fileoff_t bno, /* starting offset to unmap */
	xfs_filblks_t len, /* length to unmap in file */
	int flags, /* XFS_BMAPI_... */
	xfs_extnum_t nexts, /* number of extents max */
	xfs_fsblock_t firstblock, / first allocated block
	controls a.g. for allocs */
	xfs_bmap_free_t flist, / i/o: list extents to free */
	int done); / set if not done yet */

	/*
	* Check an extent list, which has just been read, for
	* any bit in the extent flag field.
	*/
	int
	xfs_check_nostate_extents(
	struct xfs_ifork *ifp,
	xfs_extnum_t idx,
	xfs_extnum_t num);

	uint
	xfs_default_attroffset(
	struct xfs_inode *ip);

	#ifdef __KERNEL__

	/*
	* Routine to be called at transaction's end by xfs_bmapi, xfs_bunmapi
	* caller. Frees all the extents that need freeing, which must be done
	* last due to locking considerations.
	*
	* Return 1 if the given transaction was committed and a new one allocated,
	* and 0 otherwise.
	*/
	int /* error */
	xfs_bmap_finish(
	struct xfs_trans *tp, / transaction pointer addr */
	xfs_bmap_free_t flist, / i/o: list extents to free */
	int committed); / xact committed or not */

	/* bmap to userspace formatter - copy to user & advance pointer */
	typedef int (xfs_bmap_format_t)(void , struct getbmapx , int *);

	/*
	* Get inode's extents as described in bmv, and format for output.
	*/
	int /* error code */
	xfs_getbmap(
	xfs_inode_t *ip,
	struct getbmapx bmv, / user bmap structure */
	xfs_bmap_format_t formatter, /* format to user */
	void arg); / formatter arg */

	/*
	* Check if the endoff is outside the last extent. If so the caller will grow
	* the allocation to a stripe unit boundary
	*/
	int
	xfs_bmap_eof(
	struct xfs_inode *ip,
	xfs_fileoff_t endoff,
	int whichfork,
	int *eof);

	/*
	* Count fsblocks of the given fork.
	*/
	int
	xfs_bmap_count_blocks(
	xfs_trans_t *tp,
	struct xfs_inode *ip,
	int whichfork,
	int *count);

	int
	xfs_bmap_punch_delalloc_range(
	struct xfs_inode *ip,
	xfs_fileoff_t start_fsb,
	xfs_fileoff_t length);
	#endif /* __KERNEL__ */

	#endif /* __XFS_BMAP_H__ */