Re: [PATCH 09/32] xfs: unify directory/attribute format definitions

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On 9/29/13 10:15 PM, Dave Chinner wrote:
> From: Dave Chinner <dchinner@xxxxxxxxxx>
> 
> The on-disk format definitions for the directory and attribute
> structures are spread across 3 header files right now, only one of
> which is dedicated to defining on-disk structures and their
> manipulation (xfs_dir2_format.h). Pull all the format definitions
> into a single header file - xfs_da_format.h - and switch all the
> code over to point at that.
> 
> Signed-off-by: Dave Chinner <dchinner@xxxxxxxxxx>

Reviewed-by: Eric Sandeen <sandeen@xxxxxxxxxx>

> ---
>  include/Makefile          |    4 +-
>  include/libxfs.h          |    6 +-
>  include/xfs_attr_leaf.h   |  230 --------
>  include/xfs_attr_remote.h |   27 -
>  include/xfs_da_btree.h    |  140 -----
>  include/xfs_da_format.h   | 1362 +++++++++++++++++++++++++++++++++++++++++++++
>  include/xfs_dir2_format.h |  964 --------------------------------
>  7 files changed, 1368 insertions(+), 1365 deletions(-)
>  create mode 100644 include/xfs_da_format.h
>  delete mode 100644 include/xfs_dir2_format.h
> 
> diff --git a/include/Makefile b/include/Makefile
> index fd2d61b..6682b9d 100644
> --- a/include/Makefile
> +++ b/include/Makefile
> @@ -26,7 +26,9 @@ QAHFILES = libxfs.h libxlog.h \
>  	xfs_btree_trace.h \
>  	xfs_cksum.h \
>  	xfs_da_btree.h \
> -	xfs_dinode.h xfs_dir2.h xfs_dir2_format.h \
> +	xfs_da_format.h \
> +	xfs_dinode.h \
> +	xfs_dir2.h \
>  	xfs_format.h \
>  	xfs_ialloc.h \
>  	xfs_ialloc_btree.h \
> diff --git a/include/libxfs.h b/include/libxfs.h
> index a5d6388..835ba37 100644
> --- a/include/libxfs.h
> +++ b/include/libxfs.h
> @@ -47,7 +47,6 @@
>  #include <xfs/xfs_inum.h>
>  #include <xfs/xfs_sb.h>
>  #include <xfs/xfs_ag.h>
> -#include <xfs/xfs_da_btree.h>
>  #include <xfs/xfs_bmap_btree.h>
>  #include <xfs/xfs_alloc_btree.h>
>  #include <xfs/xfs_ialloc_btree.h>
> @@ -267,9 +266,10 @@ extern void	libxfs_umount (xfs_mount_t *);
>  extern void	libxfs_rtmount_destroy (xfs_mount_t *);
>  
>  /*
> - * xfs/xfs_dir2_format.h needs struct xfs_mount to be defined
> + * xfs/xfs_da_format.h needs struct xfs_mount to be defined
>   */
> -#include <xfs/xfs_dir2_format.h>
> +#include <xfs/xfs_da_format.h>
> +#include <xfs/xfs_da_btree.h>
>  #include <xfs/xfs_dir2.h>
>  
>  /*
> diff --git a/include/xfs_attr_leaf.h b/include/xfs_attr_leaf.h
> index da34e64..3ec5ec0 100644
> --- a/include/xfs_attr_leaf.h
> +++ b/include/xfs_attr_leaf.h
> @@ -19,16 +19,6 @@
>  #ifndef __XFS_ATTR_LEAF_H__
>  #define	__XFS_ATTR_LEAF_H__
>  
> -/*
> - * Attribute storage layout, internal structure, access macros, etc.
> - *
> - * Attribute lists are structured around Btrees where all the data
> - * elements are in the leaf nodes.  Attribute names are hashed into an int,
> - * then that int is used as the index into the Btree.  Since the hashval
> - * of an attribute name may not be unique, we may have duplicate keys.  The
> - * internal links in the Btree are logical block offsets into the file.
> - */
> -
>  struct attrlist;
>  struct attrlist_cursor_kern;
>  struct xfs_attr_list_context;
> @@ -38,226 +28,6 @@ struct xfs_da_state_blk;
>  struct xfs_inode;
>  struct xfs_trans;
>  
> -/*========================================================================
> - * Attribute structure when equal to XFS_LBSIZE(mp) bytes.
> - *========================================================================*/
> -
> -/*
> - * This is the structure of the leaf nodes in the Btree.
> - *
> - * Struct leaf_entry's are packed from the top.  Name/values grow from the
> - * bottom but are not packed.  The freemap contains run-length-encoded entries
> - * for the free bytes after the leaf_entry's, but only the N largest such,
> - * smaller runs are dropped.  When the freemap doesn't show enough space
> - * for an allocation, we compact the name/value area and try again.  If we
> - * still don't have enough space, then we have to split the block.  The
> - * name/value structs (both local and remote versions) must be 32bit aligned.
> - *
> - * Since we have duplicate hash keys, for each key that matches, compare
> - * the actual name string.  The root and intermediate node search always
> - * takes the first-in-the-block key match found, so we should only have
> - * to work "forw"ard.  If none matches, continue with the "forw"ard leaf
> - * nodes until the hash key changes or the attribute name is found.
> - *
> - * We store the fact that an attribute is a ROOT/USER/SECURE attribute in
> - * the leaf_entry.  The namespaces are independent only because we also look
> - * at the namespace bit when we are looking for a matching attribute name.
> - *
> - * We also store an "incomplete" bit in the leaf_entry.  It shows that an
> - * attribute is in the middle of being created and should not be shown to
> - * the user if we crash during the time that the bit is set.  We clear the
> - * bit when we have finished setting up the attribute.  We do this because
> - * we cannot create some large attributes inside a single transaction, and we
> - * need some indication that we weren't finished if we crash in the middle.
> - */
> -#define XFS_ATTR_LEAF_MAPSIZE	3	/* how many freespace slots */
> -
> -typedef struct xfs_attr_leaf_map {	/* RLE map of free bytes */
> -	__be16	base;			  /* base of free region */
> -	__be16	size;			  /* length of free region */
> -} xfs_attr_leaf_map_t;
> -
> -typedef struct xfs_attr_leaf_hdr {	/* constant-structure header block */
> -	xfs_da_blkinfo_t info;		/* block type, links, etc. */
> -	__be16	count;			/* count of active leaf_entry's */
> -	__be16	usedbytes;		/* num bytes of names/values stored */
> -	__be16	firstused;		/* first used byte in name area */
> -	__u8	holes;			/* != 0 if blk needs compaction */
> -	__u8	pad1;
> -	xfs_attr_leaf_map_t freemap[XFS_ATTR_LEAF_MAPSIZE];
> -					/* N largest free regions */
> -} xfs_attr_leaf_hdr_t;
> -
> -typedef struct xfs_attr_leaf_entry {	/* sorted on key, not name */
> -	__be32	hashval;		/* hash value of name */
> -	__be16	nameidx;		/* index into buffer of name/value */
> -	__u8	flags;			/* LOCAL/ROOT/SECURE/INCOMPLETE flag */
> -	__u8	pad2;			/* unused pad byte */
> -} xfs_attr_leaf_entry_t;
> -
> -typedef struct xfs_attr_leaf_name_local {
> -	__be16	valuelen;		/* number of bytes in value */
> -	__u8	namelen;		/* length of name bytes */
> -	__u8	nameval[1];		/* name/value bytes */
> -} xfs_attr_leaf_name_local_t;
> -
> -typedef struct xfs_attr_leaf_name_remote {
> -	__be32	valueblk;		/* block number of value bytes */
> -	__be32	valuelen;		/* number of bytes in value */
> -	__u8	namelen;		/* length of name bytes */
> -	__u8	name[1];		/* name bytes */
> -} xfs_attr_leaf_name_remote_t;
> -
> -typedef struct xfs_attr_leafblock {
> -	xfs_attr_leaf_hdr_t	hdr;	/* constant-structure header block */
> -	xfs_attr_leaf_entry_t	entries[1];	/* sorted on key, not name */
> -	xfs_attr_leaf_name_local_t namelist;	/* grows from bottom of buf */
> -	xfs_attr_leaf_name_remote_t valuelist;	/* grows from bottom of buf */
> -} xfs_attr_leafblock_t;
> -
> -/*
> - * CRC enabled leaf structures. Called "version 3" structures to match the
> - * version number of the directory and dablk structures for this feature, and
> - * attr2 is already taken by the variable inode attribute fork size feature.
> - */
> -struct xfs_attr3_leaf_hdr {
> -	struct xfs_da3_blkinfo	info;
> -	__be16			count;
> -	__be16			usedbytes;
> -	__be16			firstused;
> -	__u8			holes;
> -	__u8			pad1;
> -	struct xfs_attr_leaf_map freemap[XFS_ATTR_LEAF_MAPSIZE];
> -	__be32			pad2;		/* 64 bit alignment */
> -};
> -
> -#define XFS_ATTR3_LEAF_CRC_OFF	(offsetof(struct xfs_attr3_leaf_hdr, info.crc))
> -
> -struct xfs_attr3_leafblock {
> -	struct xfs_attr3_leaf_hdr	hdr;
> -	struct xfs_attr_leaf_entry	entries[1];
> -
> -	/*
> -	 * The rest of the block contains the following structures after the
> -	 * leaf entries, growing from the bottom up. The variables are never
> -	 * referenced, the locations accessed purely from helper functions.
> -	 *
> -	 * struct xfs_attr_leaf_name_local
> -	 * struct xfs_attr_leaf_name_remote
> -	 */
> -};
> -
> -/*
> - * incore, neutral version of the attribute leaf header
> - */
> -struct xfs_attr3_icleaf_hdr {
> -	__uint32_t	forw;
> -	__uint32_t	back;
> -	__uint16_t	magic;
> -	__uint16_t	count;
> -	__uint16_t	usedbytes;
> -	__uint16_t	firstused;
> -	__u8		holes;
> -	struct {
> -		__uint16_t	base;
> -		__uint16_t	size;
> -	} freemap[XFS_ATTR_LEAF_MAPSIZE];
> -};
> -
> -/*
> - * Flags used in the leaf_entry[i].flags field.
> - * NOTE: the INCOMPLETE bit must not collide with the flags bits specified
> - * on the system call, they are "or"ed together for various operations.
> - */
> -#define	XFS_ATTR_LOCAL_BIT	0	/* attr is stored locally */
> -#define	XFS_ATTR_ROOT_BIT	1	/* limit access to trusted attrs */
> -#define	XFS_ATTR_SECURE_BIT	2	/* limit access to secure attrs */
> -#define	XFS_ATTR_INCOMPLETE_BIT	7	/* attr in middle of create/delete */
> -#define XFS_ATTR_LOCAL		(1 << XFS_ATTR_LOCAL_BIT)
> -#define XFS_ATTR_ROOT		(1 << XFS_ATTR_ROOT_BIT)
> -#define XFS_ATTR_SECURE		(1 << XFS_ATTR_SECURE_BIT)
> -#define XFS_ATTR_INCOMPLETE	(1 << XFS_ATTR_INCOMPLETE_BIT)
> -
> -/*
> - * Conversion macros for converting namespace bits from argument flags
> - * to ondisk flags.
> - */
> -#define XFS_ATTR_NSP_ARGS_MASK		(ATTR_ROOT | ATTR_SECURE)
> -#define XFS_ATTR_NSP_ONDISK_MASK	(XFS_ATTR_ROOT | XFS_ATTR_SECURE)
> -#define XFS_ATTR_NSP_ONDISK(flags)	((flags) & XFS_ATTR_NSP_ONDISK_MASK)
> -#define XFS_ATTR_NSP_ARGS(flags)	((flags) & XFS_ATTR_NSP_ARGS_MASK)
> -#define XFS_ATTR_NSP_ARGS_TO_ONDISK(x)	(((x) & ATTR_ROOT ? XFS_ATTR_ROOT : 0) |\
> -					 ((x) & ATTR_SECURE ? XFS_ATTR_SECURE : 0))
> -#define XFS_ATTR_NSP_ONDISK_TO_ARGS(x)	(((x) & XFS_ATTR_ROOT ? ATTR_ROOT : 0) |\
> -					 ((x) & XFS_ATTR_SECURE ? ATTR_SECURE : 0))
> -
> -/*
> - * Alignment for namelist and valuelist entries (since they are mixed
> - * there can be only one alignment value)
> - */
> -#define	XFS_ATTR_LEAF_NAME_ALIGN	((uint)sizeof(xfs_dablk_t))
> -
> -static inline int
> -xfs_attr3_leaf_hdr_size(struct xfs_attr_leafblock *leafp)
> -{
> -	if (leafp->hdr.info.magic == cpu_to_be16(XFS_ATTR3_LEAF_MAGIC))
> -		return sizeof(struct xfs_attr3_leaf_hdr);
> -	return sizeof(struct xfs_attr_leaf_hdr);
> -}
> -
> -static inline struct xfs_attr_leaf_entry *
> -xfs_attr3_leaf_entryp(xfs_attr_leafblock_t *leafp)
> -{
> -	if (leafp->hdr.info.magic == cpu_to_be16(XFS_ATTR3_LEAF_MAGIC))
> -		return &((struct xfs_attr3_leafblock *)leafp)->entries[0];
> -	return &leafp->entries[0];
> -}
> -
> -/*
> - * Cast typed pointers for "local" and "remote" name/value structs.
> - */
> -static inline char *
> -xfs_attr3_leaf_name(xfs_attr_leafblock_t *leafp, int idx)
> -{
> -	struct xfs_attr_leaf_entry *entries = xfs_attr3_leaf_entryp(leafp);
> -
> -	return &((char *)leafp)[be16_to_cpu(entries[idx].nameidx)];
> -}
> -
> -static inline xfs_attr_leaf_name_remote_t *
> -xfs_attr3_leaf_name_remote(xfs_attr_leafblock_t *leafp, int idx)
> -{
> -	return (xfs_attr_leaf_name_remote_t *)xfs_attr3_leaf_name(leafp, idx);
> -}
> -
> -static inline xfs_attr_leaf_name_local_t *
> -xfs_attr3_leaf_name_local(xfs_attr_leafblock_t *leafp, int idx)
> -{
> -	return (xfs_attr_leaf_name_local_t *)xfs_attr3_leaf_name(leafp, idx);
> -}
> -
> -/*
> - * Calculate total bytes used (including trailing pad for alignment) for
> - * a "local" name/value structure, a "remote" name/value structure, and
> - * a pointer which might be either.
> - */
> -static inline int xfs_attr_leaf_entsize_remote(int nlen)
> -{
> -	return ((uint)sizeof(xfs_attr_leaf_name_remote_t) - 1 + (nlen) + \
> -		XFS_ATTR_LEAF_NAME_ALIGN - 1) & ~(XFS_ATTR_LEAF_NAME_ALIGN - 1);
> -}
> -
> -static inline int xfs_attr_leaf_entsize_local(int nlen, int vlen)
> -{
> -	return ((uint)sizeof(xfs_attr_leaf_name_local_t) - 1 + (nlen) + (vlen) +
> -		XFS_ATTR_LEAF_NAME_ALIGN - 1) & ~(XFS_ATTR_LEAF_NAME_ALIGN - 1);
> -}
> -
> -static inline int xfs_attr_leaf_entsize_local_max(int bsize)
> -{
> -	return (((bsize) >> 1) + ((bsize) >> 2));
> -}
> -
>  /*
>   * Used to keep a list of "remote value" extents when unlinking an inode.
>   */
> diff --git a/include/xfs_attr_remote.h b/include/xfs_attr_remote.h
> index b3e1e1b..5a9acfa 100644
> --- a/include/xfs_attr_remote.h
> +++ b/include/xfs_attr_remote.h
> @@ -18,33 +18,6 @@
>  #ifndef __XFS_ATTR_REMOTE_H__
>  #define	__XFS_ATTR_REMOTE_H__
>  
> -#define XFS_ATTR3_RMT_MAGIC	0x5841524d	/* XARM */
> -
> -/*
> - * There is one of these headers per filesystem block in a remote attribute.
> - * This is done to ensure there is a 1:1 mapping between the attribute value
> - * length and the number of blocks needed to store the attribute. This makes the
> - * verification of a buffer a little more complex, but greatly simplifies the
> - * allocation, reading and writing of these attributes as we don't have to guess
> - * the number of blocks needed to store the attribute data.
> - */
> -struct xfs_attr3_rmt_hdr {
> -	__be32	rm_magic;
> -	__be32	rm_offset;
> -	__be32	rm_bytes;
> -	__be32	rm_crc;
> -	uuid_t	rm_uuid;
> -	__be64	rm_owner;
> -	__be64	rm_blkno;
> -	__be64	rm_lsn;
> -};
> -
> -#define XFS_ATTR3_RMT_CRC_OFF	offsetof(struct xfs_attr3_rmt_hdr, rm_crc)
> -
> -#define XFS_ATTR3_RMT_BUF_SPACE(mp, bufsize)	\
> -	((bufsize) - (xfs_sb_version_hascrc(&(mp)->m_sb) ? \
> -			sizeof(struct xfs_attr3_rmt_hdr) : 0))
> -
>  int xfs_attr3_rmt_blocks(struct xfs_mount *mp, int attrlen);
>  
>  int xfs_attr_rmtval_get(struct xfs_da_args *args);
> diff --git a/include/xfs_da_btree.h b/include/xfs_da_btree.h
> index a762cfa..e492dca 100644
> --- a/include/xfs_da_btree.h
> +++ b/include/xfs_da_btree.h
> @@ -25,146 +25,6 @@ struct xfs_trans;
>  struct zone;
>  
>  /*========================================================================
> - * Directory Structure when greater than XFS_LBSIZE(mp) bytes.
> - *========================================================================*/
> -
> -/*
> - * This structure is common to both leaf nodes and non-leaf nodes in the Btree.
> - *
> - * It is used to manage a doubly linked list of all blocks at the same
> - * level in the Btree, and to identify which type of block this is.
> - */
> -#define XFS_DA_NODE_MAGIC	0xfebe	/* magic number: non-leaf blocks */
> -#define XFS_ATTR_LEAF_MAGIC	0xfbee	/* magic number: attribute leaf blks */
> -#define	XFS_DIR2_LEAF1_MAGIC	0xd2f1	/* magic number: v2 dirlf single blks */
> -#define	XFS_DIR2_LEAFN_MAGIC	0xd2ff	/* magic number: v2 dirlf multi blks */
> -
> -typedef struct xfs_da_blkinfo {
> -	__be32		forw;			/* previous block in list */
> -	__be32		back;			/* following block in list */
> -	__be16		magic;			/* validity check on block */
> -	__be16		pad;			/* unused */
> -} xfs_da_blkinfo_t;
> -
> -/*
> - * CRC enabled directory structure types
> - *
> - * The headers change size for the additional verification information, but
> - * otherwise the tree layouts and contents are unchanged. Hence the da btree
> - * code can use the struct xfs_da_blkinfo for manipulating the tree links and
> - * magic numbers without modification for both v2 and v3 nodes.
> - */
> -#define XFS_DA3_NODE_MAGIC	0x3ebe	/* magic number: non-leaf blocks */
> -#define XFS_ATTR3_LEAF_MAGIC	0x3bee	/* magic number: attribute leaf blks */
> -#define	XFS_DIR3_LEAF1_MAGIC	0x3df1	/* magic number: v2 dirlf single blks */
> -#define	XFS_DIR3_LEAFN_MAGIC	0x3dff	/* magic number: v2 dirlf multi blks */
> -
> -struct xfs_da3_blkinfo {
> -	/*
> -	 * the node link manipulation code relies on the fact that the first
> -	 * element of this structure is the struct xfs_da_blkinfo so it can
> -	 * ignore the differences in the rest of the structures.
> -	 */
> -	struct xfs_da_blkinfo	hdr;
> -	__be32			crc;	/* CRC of block */
> -	__be64			blkno;	/* first block of the buffer */
> -	__be64			lsn;	/* sequence number of last write */
> -	uuid_t			uuid;	/* filesystem we belong to */
> -	__be64			owner;	/* inode that owns the block */
> -};
> -
> -/*
> - * This is the structure of the root and intermediate nodes in the Btree.
> - * The leaf nodes are defined above.
> - *
> - * Entries are not packed.
> - *
> - * Since we have duplicate keys, use a binary search but always follow
> - * all match in the block, not just the first match found.
> - */
> -#define	XFS_DA_NODE_MAXDEPTH	5	/* max depth of Btree */
> -
> -typedef struct xfs_da_node_hdr {
> -	struct xfs_da_blkinfo	info;	/* block type, links, etc. */
> -	__be16			__count; /* count of active entries */
> -	__be16			__level; /* level above leaves (leaf == 0) */
> -} xfs_da_node_hdr_t;
> -
> -struct xfs_da3_node_hdr {
> -	struct xfs_da3_blkinfo	info;	/* block type, links, etc. */
> -	__be16			__count; /* count of active entries */
> -	__be16			__level; /* level above leaves (leaf == 0) */
> -	__be32			__pad32;
> -};
> -
> -#define XFS_DA3_NODE_CRC_OFF	(offsetof(struct xfs_da3_node_hdr, info.crc))
> -
> -typedef struct xfs_da_node_entry {
> -	__be32	hashval;	/* hash value for this descendant */
> -	__be32	before;		/* Btree block before this key */
> -} xfs_da_node_entry_t;
> -
> -typedef struct xfs_da_intnode {
> -	struct xfs_da_node_hdr	hdr;
> -	struct xfs_da_node_entry __btree[];
> -} xfs_da_intnode_t;
> -
> -struct xfs_da3_intnode {
> -	struct xfs_da3_node_hdr	hdr;
> -	struct xfs_da_node_entry __btree[];
> -};
> -
> -/*
> - * In-core version of the node header to abstract the differences in the v2 and
> - * v3 disk format of the headers. Callers need to convert to/from disk format as
> - * appropriate.
> - */
> -struct xfs_da3_icnode_hdr {
> -	__uint32_t	forw;
> -	__uint32_t	back;
> -	__uint16_t	magic;
> -	__uint16_t	count;
> -	__uint16_t	level;
> -};
> -
> -extern void xfs_da3_node_hdr_from_disk(struct xfs_da3_icnode_hdr *to,
> -				       struct xfs_da_intnode *from);
> -extern void xfs_da3_node_hdr_to_disk(struct xfs_da_intnode *to,
> -				     struct xfs_da3_icnode_hdr *from);
> -
> -static inline int
> -__xfs_da3_node_hdr_size(bool v3)
> -{
> -	if (v3)
> -		return sizeof(struct xfs_da3_node_hdr);
> -	return sizeof(struct xfs_da_node_hdr);
> -}
> -static inline int
> -xfs_da3_node_hdr_size(struct xfs_da_intnode *dap)
> -{
> -	bool	v3 = dap->hdr.info.magic == cpu_to_be16(XFS_DA3_NODE_MAGIC);
> -
> -	return __xfs_da3_node_hdr_size(v3);
> -}
> -
> -static inline struct xfs_da_node_entry *
> -xfs_da3_node_tree_p(struct xfs_da_intnode *dap)
> -{
> -	if (dap->hdr.info.magic == cpu_to_be16(XFS_DA3_NODE_MAGIC)) {
> -		struct xfs_da3_intnode *dap3 = (struct xfs_da3_intnode *)dap;
> -		return dap3->__btree;
> -	}
> -	return dap->__btree;
> -}
> -
> -extern void xfs_da3_intnode_from_disk(struct xfs_da3_icnode_hdr *to,
> -				      struct xfs_da_intnode *from);
> -extern void xfs_da3_intnode_to_disk(struct xfs_da_intnode *to,
> -				    struct xfs_da3_icnode_hdr *from);
> -
> -#define	XFS_LBSIZE(mp)	(mp)->m_sb.sb_blocksize
> -
> -/*========================================================================
>   * Btree searching and modification structure definitions.
>   *========================================================================*/
>  
> diff --git a/include/xfs_da_format.h b/include/xfs_da_format.h
> new file mode 100644
> index 0000000..89a1a21
> --- /dev/null
> +++ b/include/xfs_da_format.h
> @@ -0,0 +1,1362 @@
> +/*
> + * Copyright (c) 2000-2001,2005 Silicon Graphics, Inc.
> + * Copyright (c) 2013 Red Hat, 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_DA_FORMAT_H__
> +#define __XFS_DA_FORMAT_H__
> +
> +/*========================================================================
> + * Directory Structure when greater than XFS_LBSIZE(mp) bytes.
> + *========================================================================*/
> +
> +/*
> + * This structure is common to both leaf nodes and non-leaf nodes in the Btree.
> + *
> + * It is used to manage a doubly linked list of all blocks at the same
> + * level in the Btree, and to identify which type of block this is.
> + */
> +#define XFS_DA_NODE_MAGIC	0xfebe	/* magic number: non-leaf blocks */
> +#define XFS_ATTR_LEAF_MAGIC	0xfbee	/* magic number: attribute leaf blks */
> +#define	XFS_DIR2_LEAF1_MAGIC	0xd2f1	/* magic number: v2 dirlf single blks */
> +#define	XFS_DIR2_LEAFN_MAGIC	0xd2ff	/* magic number: v2 dirlf multi blks */
> +
> +typedef struct xfs_da_blkinfo {
> +	__be32		forw;			/* previous block in list */
> +	__be32		back;			/* following block in list */
> +	__be16		magic;			/* validity check on block */
> +	__be16		pad;			/* unused */
> +} xfs_da_blkinfo_t;
> +
> +/*
> + * CRC enabled directory structure types
> + *
> + * The headers change size for the additional verification information, but
> + * otherwise the tree layouts and contents are unchanged. Hence the da btree
> + * code can use the struct xfs_da_blkinfo for manipulating the tree links and
> + * magic numbers without modification for both v2 and v3 nodes.
> + */
> +#define XFS_DA3_NODE_MAGIC	0x3ebe	/* magic number: non-leaf blocks */
> +#define XFS_ATTR3_LEAF_MAGIC	0x3bee	/* magic number: attribute leaf blks */
> +#define	XFS_DIR3_LEAF1_MAGIC	0x3df1	/* magic number: v2 dirlf single blks */
> +#define	XFS_DIR3_LEAFN_MAGIC	0x3dff	/* magic number: v2 dirlf multi blks */
> +
> +struct xfs_da3_blkinfo {
> +	/*
> +	 * the node link manipulation code relies on the fact that the first
> +	 * element of this structure is the struct xfs_da_blkinfo so it can
> +	 * ignore the differences in the rest of the structures.
> +	 */
> +	struct xfs_da_blkinfo	hdr;
> +	__be32			crc;	/* CRC of block */
> +	__be64			blkno;	/* first block of the buffer */
> +	__be64			lsn;	/* sequence number of last write */
> +	uuid_t			uuid;	/* filesystem we belong to */
> +	__be64			owner;	/* inode that owns the block */
> +};
> +
> +/*
> + * This is the structure of the root and intermediate nodes in the Btree.
> + * The leaf nodes are defined above.
> + *
> + * Entries are not packed.
> + *
> + * Since we have duplicate keys, use a binary search but always follow
> + * all match in the block, not just the first match found.
> + */
> +#define	XFS_DA_NODE_MAXDEPTH	5	/* max depth of Btree */
> +
> +typedef struct xfs_da_node_hdr {
> +	struct xfs_da_blkinfo	info;	/* block type, links, etc. */
> +	__be16			__count; /* count of active entries */
> +	__be16			__level; /* level above leaves (leaf == 0) */
> +} xfs_da_node_hdr_t;
> +
> +struct xfs_da3_node_hdr {
> +	struct xfs_da3_blkinfo	info;	/* block type, links, etc. */
> +	__be16			__count; /* count of active entries */
> +	__be16			__level; /* level above leaves (leaf == 0) */
> +	__be32			__pad32;
> +};
> +
> +#define XFS_DA3_NODE_CRC_OFF	(offsetof(struct xfs_da3_node_hdr, info.crc))
> +
> +typedef struct xfs_da_node_entry {
> +	__be32	hashval;	/* hash value for this descendant */
> +	__be32	before;		/* Btree block before this key */
> +} xfs_da_node_entry_t;
> +
> +typedef struct xfs_da_intnode {
> +	struct xfs_da_node_hdr	hdr;
> +	struct xfs_da_node_entry __btree[];
> +} xfs_da_intnode_t;
> +
> +struct xfs_da3_intnode {
> +	struct xfs_da3_node_hdr	hdr;
> +	struct xfs_da_node_entry __btree[];
> +};
> +
> +/*
> + * In-core version of the node header to abstract the differences in the v2 and
> + * v3 disk format of the headers. Callers need to convert to/from disk format as
> + * appropriate.
> + */
> +struct xfs_da3_icnode_hdr {
> +	__uint32_t	forw;
> +	__uint32_t	back;
> +	__uint16_t	magic;
> +	__uint16_t	count;
> +	__uint16_t	level;
> +};
> +
> +extern void xfs_da3_node_hdr_from_disk(struct xfs_da3_icnode_hdr *to,
> +				       struct xfs_da_intnode *from);
> +extern void xfs_da3_node_hdr_to_disk(struct xfs_da_intnode *to,
> +				     struct xfs_da3_icnode_hdr *from);
> +
> +static inline int
> +__xfs_da3_node_hdr_size(bool v3)
> +{
> +	if (v3)
> +		return sizeof(struct xfs_da3_node_hdr);
> +	return sizeof(struct xfs_da_node_hdr);
> +}
> +static inline int
> +xfs_da3_node_hdr_size(struct xfs_da_intnode *dap)
> +{
> +	bool	v3 = dap->hdr.info.magic == cpu_to_be16(XFS_DA3_NODE_MAGIC);
> +
> +	return __xfs_da3_node_hdr_size(v3);
> +}
> +
> +static inline struct xfs_da_node_entry *
> +xfs_da3_node_tree_p(struct xfs_da_intnode *dap)
> +{
> +	if (dap->hdr.info.magic == cpu_to_be16(XFS_DA3_NODE_MAGIC)) {
> +		struct xfs_da3_intnode *dap3 = (struct xfs_da3_intnode *)dap;
> +		return dap3->__btree;
> +	}
> +	return dap->__btree;
> +}
> +
> +extern void xfs_da3_intnode_from_disk(struct xfs_da3_icnode_hdr *to,
> +				      struct xfs_da_intnode *from);
> +extern void xfs_da3_intnode_to_disk(struct xfs_da_intnode *to,
> +				    struct xfs_da3_icnode_hdr *from);
> +
> +#define	XFS_LBSIZE(mp)	(mp)->m_sb.sb_blocksize
> +
> +/*
> + * Directory version 2.
> + *
> + * There are 4 possible formats:
> + *  - shortform - embedded into the inode
> + *  - single block - data with embedded leaf at the end
> + *  - multiple data blocks, single leaf+freeindex block
> + *  - data blocks, node and leaf blocks (btree), freeindex blocks
> + *
> + * Note: many node blocks structures and constants are shared with the attr
> + * code and defined in xfs_da_btree.h.
> + */
> +
> +#define	XFS_DIR2_BLOCK_MAGIC	0x58443242	/* XD2B: single block dirs */
> +#define	XFS_DIR2_DATA_MAGIC	0x58443244	/* XD2D: multiblock dirs */
> +#define	XFS_DIR2_FREE_MAGIC	0x58443246	/* XD2F: free index blocks */
> +
> +/*
> + * Directory Version 3 With CRCs.
> + *
> + * The tree formats are the same as for version 2 directories.  The difference
> + * is in the block header and dirent formats. In many cases the v3 structures
> + * use v2 definitions as they are no different and this makes code sharing much
> + * easier.
> + *
> + * Also, the xfs_dir3_*() functions handle both v2 and v3 formats - if the
> + * format is v2 then they switch to the existing v2 code, or the format is v3
> + * they implement the v3 functionality. This means the existing dir2 is a mix of
> + * xfs_dir2/xfs_dir3 calls and functions. The xfs_dir3 functions are called
> + * where there is a difference in the formats, otherwise the code is unchanged.
> + *
> + * Where it is possible, the code decides what to do based on the magic numbers
> + * in the blocks rather than feature bits in the superblock. This means the code
> + * is as independent of the external XFS code as possible as doesn't require
> + * passing struct xfs_mount pointers into places where it isn't really
> + * necessary.
> + *
> + * Version 3 includes:
> + *
> + *	- a larger block header for CRC and identification purposes and so the
> + *	offsets of all the structures inside the blocks are different.
> + *
> + *	- new magic numbers to be able to detect the v2/v3 types on the fly.
> + */
> +
> +#define	XFS_DIR3_BLOCK_MAGIC	0x58444233	/* XDB3: single block dirs */
> +#define	XFS_DIR3_DATA_MAGIC	0x58444433	/* XDD3: multiblock dirs */
> +#define	XFS_DIR3_FREE_MAGIC	0x58444633	/* XDF3: free index blocks */
> +
> +/*
> + * Dirents in version 3 directories have a file type field. Additions to this
> + * list are an on-disk format change, requiring feature bits. Valid values
> + * are as follows:
> + */
> +#define XFS_DIR3_FT_UNKNOWN		0
> +#define XFS_DIR3_FT_REG_FILE		1
> +#define XFS_DIR3_FT_DIR			2
> +#define XFS_DIR3_FT_CHRDEV		3
> +#define XFS_DIR3_FT_BLKDEV		4
> +#define XFS_DIR3_FT_FIFO		5
> +#define XFS_DIR3_FT_SOCK		6
> +#define XFS_DIR3_FT_SYMLINK		7
> +#define XFS_DIR3_FT_WHT			8
> +
> +#define XFS_DIR3_FT_MAX			9
> +
> +/*
> + * Byte offset in data block and shortform entry.
> + */
> +typedef	__uint16_t	xfs_dir2_data_off_t;
> +#define	NULLDATAOFF	0xffffU
> +typedef uint		xfs_dir2_data_aoff_t;	/* argument form */
> +
> +/*
> + * Normalized offset (in a data block) of the entry, really xfs_dir2_data_off_t.
> + * Only need 16 bits, this is the byte offset into the single block form.
> + */
> +typedef struct { __uint8_t i[2]; } __arch_pack xfs_dir2_sf_off_t;
> +
> +/*
> + * Offset in data space of a data entry.
> + */
> +typedef	__uint32_t	xfs_dir2_dataptr_t;
> +#define	XFS_DIR2_MAX_DATAPTR	((xfs_dir2_dataptr_t)0xffffffff)
> +#define	XFS_DIR2_NULL_DATAPTR	((xfs_dir2_dataptr_t)0)
> +
> +/*
> + * Byte offset in a directory.
> + */
> +typedef	xfs_off_t	xfs_dir2_off_t;
> +
> +/*
> + * Directory block number (logical dirblk in file)
> + */
> +typedef	__uint32_t	xfs_dir2_db_t;
> +
> +/*
> + * Inode number stored as 8 8-bit values.
> + */
> +typedef	struct { __uint8_t i[8]; } xfs_dir2_ino8_t;
> +
> +/*
> + * Inode number stored as 4 8-bit values.
> + * Works a lot of the time, when all the inode numbers in a directory
> + * fit in 32 bits.
> + */
> +typedef struct { __uint8_t i[4]; } xfs_dir2_ino4_t;
> +
> +typedef union {
> +	xfs_dir2_ino8_t	i8;
> +	xfs_dir2_ino4_t	i4;
> +} xfs_dir2_inou_t;
> +#define	XFS_DIR2_MAX_SHORT_INUM	((xfs_ino_t)0xffffffffULL)
> +
> +/*
> + * Directory layout when stored internal to an inode.
> + *
> + * Small directories are packed as tightly as possible so as to fit into the
> + * literal area of the inode.  These "shortform" directories consist of a
> + * single xfs_dir2_sf_hdr header followed by zero or more xfs_dir2_sf_entry
> + * structures.  Due the different inode number storage size and the variable
> + * length name field in the xfs_dir2_sf_entry all these structure are
> + * variable length, and the accessors in this file should be used to iterate
> + * over them.
> + */
> +typedef struct xfs_dir2_sf_hdr {
> +	__uint8_t		count;		/* count of entries */
> +	__uint8_t		i8count;	/* count of 8-byte inode #s */
> +	xfs_dir2_inou_t		parent;		/* parent dir inode number */
> +} __arch_pack xfs_dir2_sf_hdr_t;
> +
> +typedef struct xfs_dir2_sf_entry {
> +	__u8			namelen;	/* actual name length */
> +	xfs_dir2_sf_off_t	offset;		/* saved offset */
> +	__u8			name[];		/* name, variable size */
> +	/*
> +	 * A single byte containing the file type field follows the inode
> +	 * number for version 3 directory entries.
> +	 *
> +	 * A xfs_dir2_ino8_t or xfs_dir2_ino4_t follows here, at a
> +	 * variable offset after the name.
> +	 */
> +} __arch_pack xfs_dir2_sf_entry_t;
> +
> +static inline int xfs_dir2_sf_hdr_size(int i8count)
> +{
> +	return sizeof(struct xfs_dir2_sf_hdr) -
> +		(i8count == 0) *
> +		(sizeof(xfs_dir2_ino8_t) - sizeof(xfs_dir2_ino4_t));
> +}
> +
> +static inline xfs_dir2_data_aoff_t
> +xfs_dir2_sf_get_offset(xfs_dir2_sf_entry_t *sfep)
> +{
> +	return get_unaligned_be16(&sfep->offset.i);
> +}
> +
> +static inline void
> +xfs_dir2_sf_put_offset(xfs_dir2_sf_entry_t *sfep, xfs_dir2_data_aoff_t off)
> +{
> +	put_unaligned_be16(off, &sfep->offset.i);
> +}
> +
> +static inline struct xfs_dir2_sf_entry *
> +xfs_dir2_sf_firstentry(struct xfs_dir2_sf_hdr *hdr)
> +{
> +	return (struct xfs_dir2_sf_entry *)
> +		((char *)hdr + xfs_dir2_sf_hdr_size(hdr->i8count));
> +}
> +
> +static inline int
> +xfs_dir3_sf_entsize(
> +	struct xfs_mount	*mp,
> +	struct xfs_dir2_sf_hdr	*hdr,
> +	int			len)
> +{
> +	int count = sizeof(struct xfs_dir2_sf_entry); 	/* namelen + offset */
> +
> +	count += len;					/* name */
> +	count += hdr->i8count ? sizeof(xfs_dir2_ino8_t) :
> +				sizeof(xfs_dir2_ino4_t); /* ino # */
> +	if (xfs_sb_version_hasftype(&mp->m_sb))
> +		count += sizeof(__uint8_t);		/* file type */
> +	return count;
> +}
> +
> +static inline struct xfs_dir2_sf_entry *
> +xfs_dir3_sf_nextentry(
> +	struct xfs_mount	*mp,
> +	struct xfs_dir2_sf_hdr	*hdr,
> +	struct xfs_dir2_sf_entry *sfep)
> +{
> +	return (struct xfs_dir2_sf_entry *)
> +		((char *)sfep + xfs_dir3_sf_entsize(mp, hdr, sfep->namelen));
> +}
> +
> +/*
> + * in dir3 shortform directories, the file type field is stored at a variable
> + * offset after the inode number. Because it's only a single byte, endian
> + * conversion is not necessary.
> + */
> +static inline __uint8_t *
> +xfs_dir3_sfe_ftypep(
> +	struct xfs_dir2_sf_hdr	*hdr,
> +	struct xfs_dir2_sf_entry *sfep)
> +{
> +	return (__uint8_t *)&sfep->name[sfep->namelen];
> +}
> +
> +static inline __uint8_t
> +xfs_dir3_sfe_get_ftype(
> +	struct xfs_mount	*mp,
> +	struct xfs_dir2_sf_hdr	*hdr,
> +	struct xfs_dir2_sf_entry *sfep)
> +{
> +	__uint8_t	*ftp;
> +
> +	if (!xfs_sb_version_hasftype(&mp->m_sb))
> +		return XFS_DIR3_FT_UNKNOWN;
> +
> +	ftp = xfs_dir3_sfe_ftypep(hdr, sfep);
> +	if (*ftp >= XFS_DIR3_FT_MAX)
> +		return XFS_DIR3_FT_UNKNOWN;
> +	return *ftp;
> +}
> +
> +static inline void
> +xfs_dir3_sfe_put_ftype(
> +	struct xfs_mount	*mp,
> +	struct xfs_dir2_sf_hdr	*hdr,
> +	struct xfs_dir2_sf_entry *sfep,
> +	__uint8_t		ftype)
> +{
> +	__uint8_t	*ftp;
> +
> +	ASSERT(ftype < XFS_DIR3_FT_MAX);
> +
> +	if (!xfs_sb_version_hasftype(&mp->m_sb))
> +		return;
> +	ftp = xfs_dir3_sfe_ftypep(hdr, sfep);
> +	*ftp = ftype;
> +}
> +
> +/*
> + * Data block structures.
> + *
> + * A pure data block looks like the following drawing on disk:
> + *
> + *    +-------------------------------------------------+
> + *    | xfs_dir2_data_hdr_t                             |
> + *    +-------------------------------------------------+
> + *    | xfs_dir2_data_entry_t OR xfs_dir2_data_unused_t |
> + *    | xfs_dir2_data_entry_t OR xfs_dir2_data_unused_t |
> + *    | xfs_dir2_data_entry_t OR xfs_dir2_data_unused_t |
> + *    | ...                                             |
> + *    +-------------------------------------------------+
> + *    | unused space                                    |
> + *    +-------------------------------------------------+
> + *
> + * As all the entries are variable size structures the accessors below should
> + * be used to iterate over them.
> + *
> + * In addition to the pure data blocks for the data and node formats,
> + * most structures are also used for the combined data/freespace "block"
> + * format below.
> + */
> +
> +#define	XFS_DIR2_DATA_ALIGN_LOG	3		/* i.e., 8 bytes */
> +#define	XFS_DIR2_DATA_ALIGN	(1 << XFS_DIR2_DATA_ALIGN_LOG)
> +#define	XFS_DIR2_DATA_FREE_TAG	0xffff
> +#define	XFS_DIR2_DATA_FD_COUNT	3
> +
> +/*
> + * Directory address space divided into sections,
> + * spaces separated by 32GB.
> + */
> +#define	XFS_DIR2_SPACE_SIZE	(1ULL << (32 + XFS_DIR2_DATA_ALIGN_LOG))
> +#define	XFS_DIR2_DATA_SPACE	0
> +#define	XFS_DIR2_DATA_OFFSET	(XFS_DIR2_DATA_SPACE * XFS_DIR2_SPACE_SIZE)
> +#define	XFS_DIR2_DATA_FIRSTDB(mp)	\
> +	xfs_dir2_byte_to_db(mp, XFS_DIR2_DATA_OFFSET)
> +
> +/*
> + * Describe a free area in the data block.
> + *
> + * The freespace will be formatted as a xfs_dir2_data_unused_t.
> + */
> +typedef struct xfs_dir2_data_free {
> +	__be16			offset;		/* start of freespace */
> +	__be16			length;		/* length of freespace */
> +} xfs_dir2_data_free_t;
> +
> +/*
> + * Header for the data blocks.
> + *
> + * The code knows that XFS_DIR2_DATA_FD_COUNT is 3.
> + */
> +typedef struct xfs_dir2_data_hdr {
> +	__be32			magic;		/* XFS_DIR2_DATA_MAGIC or */
> +						/* XFS_DIR2_BLOCK_MAGIC */
> +	xfs_dir2_data_free_t	bestfree[XFS_DIR2_DATA_FD_COUNT];
> +} xfs_dir2_data_hdr_t;
> +
> +/*
> + * define a structure for all the verification fields we are adding to the
> + * directory block structures. This will be used in several structures.
> + * The magic number must be the first entry to align with all the dir2
> + * structures so we determine how to decode them just by the magic number.
> + */
> +struct xfs_dir3_blk_hdr {
> +	__be32			magic;	/* magic number */
> +	__be32			crc;	/* CRC of block */
> +	__be64			blkno;	/* first block of the buffer */
> +	__be64			lsn;	/* sequence number of last write */
> +	uuid_t			uuid;	/* filesystem we belong to */
> +	__be64			owner;	/* inode that owns the block */
> +};
> +
> +struct xfs_dir3_data_hdr {
> +	struct xfs_dir3_blk_hdr	hdr;
> +	xfs_dir2_data_free_t	best_free[XFS_DIR2_DATA_FD_COUNT];
> +	__be32			pad;	/* 64 bit alignment */
> +};
> +
> +#define XFS_DIR3_DATA_CRC_OFF  offsetof(struct xfs_dir3_data_hdr, hdr.crc)
> +
> +static inline struct xfs_dir2_data_free *
> +xfs_dir3_data_bestfree_p(struct xfs_dir2_data_hdr *hdr)
> +{
> +	if (hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC) ||
> +	    hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC)) {
> +		struct xfs_dir3_data_hdr *hdr3 = (struct xfs_dir3_data_hdr *)hdr;
> +		return hdr3->best_free;
> +	}
> +	return hdr->bestfree;
> +}
> +
> +/*
> + * Active entry in a data block.
> + *
> + * Aligned to 8 bytes.  After the variable length name field there is a
> + * 2 byte tag field, which can be accessed using xfs_dir3_data_entry_tag_p.
> + *
> + * For dir3 structures, there is file type field between the name and the tag.
> + * This can only be manipulated by helper functions. It is packed hard against
> + * the end of the name so any padding for rounding is between the file type and
> + * the tag.
> + */
> +typedef struct xfs_dir2_data_entry {
> +	__be64			inumber;	/* inode number */
> +	__u8			namelen;	/* name length */
> +	__u8			name[];		/* name bytes, no null */
> +     /* __u8			filetype; */	/* type of inode we point to */
> +     /*	__be16                  tag; */		/* starting offset of us */
> +} xfs_dir2_data_entry_t;
> +
> +/*
> + * Unused entry in a data block.
> + *
> + * Aligned to 8 bytes.  Tag appears as the last 2 bytes and must be accessed
> + * using xfs_dir2_data_unused_tag_p.
> + */
> +typedef struct xfs_dir2_data_unused {
> +	__be16			freetag;	/* XFS_DIR2_DATA_FREE_TAG */
> +	__be16			length;		/* total free length */
> +						/* variable offset */
> +	__be16			tag;		/* starting offset of us */
> +} xfs_dir2_data_unused_t;
> +
> +/*
> + * Size of a data entry.
> + */
> +static inline int
> +__xfs_dir3_data_entsize(
> +	bool	ftype,
> +	int	n)
> +{
> +	int	size = offsetof(struct xfs_dir2_data_entry, name[0]);
> +
> +	size += n;
> +	size += sizeof(xfs_dir2_data_off_t);
> +	if (ftype)
> +		size += sizeof(__uint8_t);
> +	return roundup(size, XFS_DIR2_DATA_ALIGN);
> +}
> +static inline int
> +xfs_dir3_data_entsize(
> +	struct xfs_mount	*mp,
> +	int			n)
> +{
> +	bool ftype = xfs_sb_version_hasftype(&mp->m_sb) ? true : false;
> +	return __xfs_dir3_data_entsize(ftype, n);
> +}
> +
> +static inline __uint8_t
> +xfs_dir3_dirent_get_ftype(
> +	struct xfs_mount	*mp,
> +	struct xfs_dir2_data_entry *dep)
> +{
> +	if (xfs_sb_version_hasftype(&mp->m_sb)) {
> +		__uint8_t	type = dep->name[dep->namelen];
> +
> +		ASSERT(type < XFS_DIR3_FT_MAX);
> +		if (type < XFS_DIR3_FT_MAX)
> +			return type;
> +
> +	}
> +	return XFS_DIR3_FT_UNKNOWN;
> +}
> +
> +static inline void
> +xfs_dir3_dirent_put_ftype(
> +	struct xfs_mount	*mp,
> +	struct xfs_dir2_data_entry *dep,
> +	__uint8_t		type)
> +{
> +	ASSERT(type < XFS_DIR3_FT_MAX);
> +	ASSERT(dep->namelen != 0);
> +
> +	if (xfs_sb_version_hasftype(&mp->m_sb))
> +		dep->name[dep->namelen] = type;
> +}
> +
> +/*
> + * Pointer to an entry's tag word.
> + */
> +static inline __be16 *
> +xfs_dir3_data_entry_tag_p(
> +	struct xfs_mount	*mp,
> +	struct xfs_dir2_data_entry *dep)
> +{
> +	return (__be16 *)((char *)dep +
> +		xfs_dir3_data_entsize(mp, dep->namelen) - sizeof(__be16));
> +}
> +
> +/*
> + * Pointer to a freespace's tag word.
> + */
> +static inline __be16 *
> +xfs_dir2_data_unused_tag_p(struct xfs_dir2_data_unused *dup)
> +{
> +	return (__be16 *)((char *)dup +
> +			be16_to_cpu(dup->length) - sizeof(__be16));
> +}
> +
> +static inline size_t
> +xfs_dir3_data_hdr_size(bool dir3)
> +{
> +	if (dir3)
> +		return sizeof(struct xfs_dir3_data_hdr);
> +	return sizeof(struct xfs_dir2_data_hdr);
> +}
> +
> +static inline size_t
> +xfs_dir3_data_entry_offset(struct xfs_dir2_data_hdr *hdr)
> +{
> +	bool dir3 = hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC) ||
> +		    hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC);
> +	return xfs_dir3_data_hdr_size(dir3);
> +}
> +
> +static inline struct xfs_dir2_data_entry *
> +xfs_dir3_data_entry_p(struct xfs_dir2_data_hdr *hdr)
> +{
> +	return (struct xfs_dir2_data_entry *)
> +		((char *)hdr + xfs_dir3_data_entry_offset(hdr));
> +}
> +
> +static inline struct xfs_dir2_data_unused *
> +xfs_dir3_data_unused_p(struct xfs_dir2_data_hdr *hdr)
> +{
> +	return (struct xfs_dir2_data_unused *)
> +		((char *)hdr + xfs_dir3_data_entry_offset(hdr));
> +}
> +
> +/*
> + * Offsets of . and .. in data space (always block 0)
> + *
> + * XXX: there is scope for significant optimisation of the logic here. Right
> + * now we are checking for "dir3 format" over and over again. Ideally we should
> + * only do it once for each operation.
> + */
> +static inline xfs_dir2_data_aoff_t
> +xfs_dir3_data_dot_offset(struct xfs_mount *mp)
> +{
> +	return xfs_dir3_data_hdr_size(xfs_sb_version_hascrc(&mp->m_sb));
> +}
> +
> +static inline xfs_dir2_data_aoff_t
> +xfs_dir3_data_dotdot_offset(struct xfs_mount *mp)
> +{
> +	return xfs_dir3_data_dot_offset(mp) +
> +		xfs_dir3_data_entsize(mp, 1);
> +}
> +
> +static inline xfs_dir2_data_aoff_t
> +xfs_dir3_data_first_offset(struct xfs_mount *mp)
> +{
> +	return xfs_dir3_data_dotdot_offset(mp) +
> +		xfs_dir3_data_entsize(mp, 2);
> +}
> +
> +/*
> + * location of . and .. in data space (always block 0)
> + */
> +static inline struct xfs_dir2_data_entry *
> +xfs_dir3_data_dot_entry_p(
> +	struct xfs_mount	*mp,
> +	struct xfs_dir2_data_hdr *hdr)
> +{
> +	return (struct xfs_dir2_data_entry *)
> +		((char *)hdr + xfs_dir3_data_dot_offset(mp));
> +}
> +
> +static inline struct xfs_dir2_data_entry *
> +xfs_dir3_data_dotdot_entry_p(
> +	struct xfs_mount	*mp,
> +	struct xfs_dir2_data_hdr *hdr)
> +{
> +	return (struct xfs_dir2_data_entry *)
> +		((char *)hdr + xfs_dir3_data_dotdot_offset(mp));
> +}
> +
> +static inline struct xfs_dir2_data_entry *
> +xfs_dir3_data_first_entry_p(
> +	struct xfs_mount	*mp,
> +	struct xfs_dir2_data_hdr *hdr)
> +{
> +	return (struct xfs_dir2_data_entry *)
> +		((char *)hdr + xfs_dir3_data_first_offset(mp));
> +}
> +
> +/*
> + * Leaf block structures.
> + *
> + * A pure leaf block looks like the following drawing on disk:
> + *
> + *    +---------------------------+
> + *    | xfs_dir2_leaf_hdr_t       |
> + *    +---------------------------+
> + *    | xfs_dir2_leaf_entry_t     |
> + *    | xfs_dir2_leaf_entry_t     |
> + *    | xfs_dir2_leaf_entry_t     |
> + *    | xfs_dir2_leaf_entry_t     |
> + *    | ...                       |
> + *    +---------------------------+
> + *    | xfs_dir2_data_off_t       |
> + *    | xfs_dir2_data_off_t       |
> + *    | xfs_dir2_data_off_t       |
> + *    | ...                       |
> + *    +---------------------------+
> + *    | xfs_dir2_leaf_tail_t      |
> + *    +---------------------------+
> + *
> + * The xfs_dir2_data_off_t members (bests) and tail are at the end of the block
> + * for single-leaf (magic = XFS_DIR2_LEAF1_MAGIC) blocks only, but not present
> + * for directories with separate leaf nodes and free space blocks
> + * (magic = XFS_DIR2_LEAFN_MAGIC).
> + *
> + * As all the entries are variable size structures the accessors below should
> + * be used to iterate over them.
> + */
> +
> +/*
> + * Offset of the leaf/node space.  First block in this space
> + * is the btree root.
> + */
> +#define	XFS_DIR2_LEAF_SPACE	1
> +#define	XFS_DIR2_LEAF_OFFSET	(XFS_DIR2_LEAF_SPACE * XFS_DIR2_SPACE_SIZE)
> +#define	XFS_DIR2_LEAF_FIRSTDB(mp)	\
> +	xfs_dir2_byte_to_db(mp, XFS_DIR2_LEAF_OFFSET)
> +
> +/*
> + * Leaf block header.
> + */
> +typedef struct xfs_dir2_leaf_hdr {
> +	xfs_da_blkinfo_t	info;		/* header for da routines */
> +	__be16			count;		/* count of entries */
> +	__be16			stale;		/* count of stale entries */
> +} xfs_dir2_leaf_hdr_t;
> +
> +struct xfs_dir3_leaf_hdr {
> +	struct xfs_da3_blkinfo	info;		/* header for da routines */
> +	__be16			count;		/* count of entries */
> +	__be16			stale;		/* count of stale entries */
> +	__be32			pad;		/* 64 bit alignment */
> +};
> +
> +struct xfs_dir3_icleaf_hdr {
> +	__uint32_t		forw;
> +	__uint32_t		back;
> +	__uint16_t		magic;
> +	__uint16_t		count;
> +	__uint16_t		stale;
> +};
> +
> +/*
> + * Leaf block entry.
> + */
> +typedef struct xfs_dir2_leaf_entry {
> +	__be32			hashval;	/* hash value of name */
> +	__be32			address;	/* address of data entry */
> +} xfs_dir2_leaf_entry_t;
> +
> +/*
> + * Leaf block tail.
> + */
> +typedef struct xfs_dir2_leaf_tail {
> +	__be32			bestcount;
> +} xfs_dir2_leaf_tail_t;
> +
> +/*
> + * Leaf block.
> + */
> +typedef struct xfs_dir2_leaf {
> +	xfs_dir2_leaf_hdr_t	hdr;			/* leaf header */
> +	xfs_dir2_leaf_entry_t	__ents[];		/* entries */
> +} xfs_dir2_leaf_t;
> +
> +struct xfs_dir3_leaf {
> +	struct xfs_dir3_leaf_hdr	hdr;		/* leaf header */
> +	struct xfs_dir2_leaf_entry	__ents[];	/* entries */
> +};
> +
> +#define XFS_DIR3_LEAF_CRC_OFF  offsetof(struct xfs_dir3_leaf_hdr, info.crc)
> +
> +extern void xfs_dir3_leaf_hdr_from_disk(struct xfs_dir3_icleaf_hdr *to,
> +					struct xfs_dir2_leaf *from);
> +
> +static inline int
> +xfs_dir3_leaf_hdr_size(struct xfs_dir2_leaf *lp)
> +{
> +	if (lp->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAF1_MAGIC) ||
> +	    lp->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAFN_MAGIC))
> +		return sizeof(struct xfs_dir3_leaf_hdr);
> +	return sizeof(struct xfs_dir2_leaf_hdr);
> +}
> +
> +static inline int
> +xfs_dir3_max_leaf_ents(struct xfs_mount *mp, struct xfs_dir2_leaf *lp)
> +{
> +	return (mp->m_dirblksize - xfs_dir3_leaf_hdr_size(lp)) /
> +		(uint)sizeof(struct xfs_dir2_leaf_entry);
> +}
> +
> +/*
> + * Get address of the bestcount field in the single-leaf block.
> + */
> +static inline struct xfs_dir2_leaf_entry *
> +xfs_dir3_leaf_ents_p(struct xfs_dir2_leaf *lp)
> +{
> +	if (lp->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAF1_MAGIC) ||
> +	    lp->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAFN_MAGIC)) {
> +		struct xfs_dir3_leaf *lp3 = (struct xfs_dir3_leaf *)lp;
> +		return lp3->__ents;
> +	}
> +	return lp->__ents;
> +}
> +
> +/*
> + * Get address of the bestcount field in the single-leaf block.
> + */
> +static inline struct xfs_dir2_leaf_tail *
> +xfs_dir2_leaf_tail_p(struct xfs_mount *mp, struct xfs_dir2_leaf *lp)
> +{
> +	return (struct xfs_dir2_leaf_tail *)
> +		((char *)lp + mp->m_dirblksize -
> +		  sizeof(struct xfs_dir2_leaf_tail));
> +}
> +
> +/*
> + * Get address of the bests array in the single-leaf block.
> + */
> +static inline __be16 *
> +xfs_dir2_leaf_bests_p(struct xfs_dir2_leaf_tail *ltp)
> +{
> +	return (__be16 *)ltp - be32_to_cpu(ltp->bestcount);
> +}
> +
> +/*
> + * DB blocks here are logical directory block numbers, not filesystem blocks.
> + */
> +
> +/*
> + * Convert dataptr to byte in file space
> + */
> +static inline xfs_dir2_off_t
> +xfs_dir2_dataptr_to_byte(struct xfs_mount *mp, xfs_dir2_dataptr_t dp)
> +{
> +	return (xfs_dir2_off_t)dp << XFS_DIR2_DATA_ALIGN_LOG;
> +}
> +
> +/*
> + * Convert byte in file space to dataptr.  It had better be aligned.
> + */
> +static inline xfs_dir2_dataptr_t
> +xfs_dir2_byte_to_dataptr(struct xfs_mount *mp, xfs_dir2_off_t by)
> +{
> +	return (xfs_dir2_dataptr_t)(by >> XFS_DIR2_DATA_ALIGN_LOG);
> +}
> +
> +/*
> + * Convert byte in space to (DB) block
> + */
> +static inline xfs_dir2_db_t
> +xfs_dir2_byte_to_db(struct xfs_mount *mp, xfs_dir2_off_t by)
> +{
> +	return (xfs_dir2_db_t)
> +		(by >> (mp->m_sb.sb_blocklog + mp->m_sb.sb_dirblklog));
> +}
> +
> +/*
> + * Convert dataptr to a block number
> + */
> +static inline xfs_dir2_db_t
> +xfs_dir2_dataptr_to_db(struct xfs_mount *mp, xfs_dir2_dataptr_t dp)
> +{
> +	return xfs_dir2_byte_to_db(mp, xfs_dir2_dataptr_to_byte(mp, dp));
> +}
> +
> +/*
> + * Convert byte in space to offset in a block
> + */
> +static inline xfs_dir2_data_aoff_t
> +xfs_dir2_byte_to_off(struct xfs_mount *mp, xfs_dir2_off_t by)
> +{
> +	return (xfs_dir2_data_aoff_t)(by &
> +		((1 << (mp->m_sb.sb_blocklog + mp->m_sb.sb_dirblklog)) - 1));
> +}
> +
> +/*
> + * Convert dataptr to a byte offset in a block
> + */
> +static inline xfs_dir2_data_aoff_t
> +xfs_dir2_dataptr_to_off(struct xfs_mount *mp, xfs_dir2_dataptr_t dp)
> +{
> +	return xfs_dir2_byte_to_off(mp, xfs_dir2_dataptr_to_byte(mp, dp));
> +}
> +
> +/*
> + * Convert block and offset to byte in space
> + */
> +static inline xfs_dir2_off_t
> +xfs_dir2_db_off_to_byte(struct xfs_mount *mp, xfs_dir2_db_t db,
> +			xfs_dir2_data_aoff_t o)
> +{
> +	return ((xfs_dir2_off_t)db <<
> +		(mp->m_sb.sb_blocklog + mp->m_sb.sb_dirblklog)) + o;
> +}
> +
> +/*
> + * Convert block (DB) to block (dablk)
> + */
> +static inline xfs_dablk_t
> +xfs_dir2_db_to_da(struct xfs_mount *mp, xfs_dir2_db_t db)
> +{
> +	return (xfs_dablk_t)(db << mp->m_sb.sb_dirblklog);
> +}
> +
> +/*
> + * Convert byte in space to (DA) block
> + */
> +static inline xfs_dablk_t
> +xfs_dir2_byte_to_da(struct xfs_mount *mp, xfs_dir2_off_t by)
> +{
> +	return xfs_dir2_db_to_da(mp, xfs_dir2_byte_to_db(mp, by));
> +}
> +
> +/*
> + * Convert block and offset to dataptr
> + */
> +static inline xfs_dir2_dataptr_t
> +xfs_dir2_db_off_to_dataptr(struct xfs_mount *mp, xfs_dir2_db_t db,
> +			   xfs_dir2_data_aoff_t o)
> +{
> +	return xfs_dir2_byte_to_dataptr(mp, xfs_dir2_db_off_to_byte(mp, db, o));
> +}
> +
> +/*
> + * Convert block (dablk) to block (DB)
> + */
> +static inline xfs_dir2_db_t
> +xfs_dir2_da_to_db(struct xfs_mount *mp, xfs_dablk_t da)
> +{
> +	return (xfs_dir2_db_t)(da >> mp->m_sb.sb_dirblklog);
> +}
> +
> +/*
> + * Convert block (dablk) to byte offset in space
> + */
> +static inline xfs_dir2_off_t
> +xfs_dir2_da_to_byte(struct xfs_mount *mp, xfs_dablk_t da)
> +{
> +	return xfs_dir2_db_off_to_byte(mp, xfs_dir2_da_to_db(mp, da), 0);
> +}
> +
> +/*
> + * Free space block defintions for the node format.
> + */
> +
> +/*
> + * Offset of the freespace index.
> + */
> +#define	XFS_DIR2_FREE_SPACE	2
> +#define	XFS_DIR2_FREE_OFFSET	(XFS_DIR2_FREE_SPACE * XFS_DIR2_SPACE_SIZE)
> +#define	XFS_DIR2_FREE_FIRSTDB(mp)	\
> +	xfs_dir2_byte_to_db(mp, XFS_DIR2_FREE_OFFSET)
> +
> +typedef	struct xfs_dir2_free_hdr {
> +	__be32			magic;		/* XFS_DIR2_FREE_MAGIC */
> +	__be32			firstdb;	/* db of first entry */
> +	__be32			nvalid;		/* count of valid entries */
> +	__be32			nused;		/* count of used entries */
> +} xfs_dir2_free_hdr_t;
> +
> +typedef struct xfs_dir2_free {
> +	xfs_dir2_free_hdr_t	hdr;		/* block header */
> +	__be16			bests[];	/* best free counts */
> +						/* unused entries are -1 */
> +} xfs_dir2_free_t;
> +
> +struct xfs_dir3_free_hdr {
> +	struct xfs_dir3_blk_hdr	hdr;
> +	__be32			firstdb;	/* db of first entry */
> +	__be32			nvalid;		/* count of valid entries */
> +	__be32			nused;		/* count of used entries */
> +	__be32			pad;		/* 64 bit alignment */
> +};
> +
> +struct xfs_dir3_free {
> +	struct xfs_dir3_free_hdr hdr;
> +	__be16			bests[];	/* best free counts */
> +						/* unused entries are -1 */
> +};
> +
> +#define XFS_DIR3_FREE_CRC_OFF  offsetof(struct xfs_dir3_free, hdr.hdr.crc)
> +
> +/*
> + * In core version of the free block header, abstracted away from on-disk format
> + * differences. Use this in the code, and convert to/from the disk version using
> + * xfs_dir3_free_hdr_from_disk/xfs_dir3_free_hdr_to_disk.
> + */
> +struct xfs_dir3_icfree_hdr {
> +	__uint32_t	magic;
> +	__uint32_t	firstdb;
> +	__uint32_t	nvalid;
> +	__uint32_t	nused;
> +
> +};
> +
> +void xfs_dir3_free_hdr_from_disk(struct xfs_dir3_icfree_hdr *to,
> +				 struct xfs_dir2_free *from);
> +
> +static inline int
> +xfs_dir3_free_hdr_size(struct xfs_mount *mp)
> +{
> +	if (xfs_sb_version_hascrc(&mp->m_sb))
> +		return sizeof(struct xfs_dir3_free_hdr);
> +	return sizeof(struct xfs_dir2_free_hdr);
> +}
> +
> +static inline int
> +xfs_dir3_free_max_bests(struct xfs_mount *mp)
> +{
> +	return (mp->m_dirblksize - xfs_dir3_free_hdr_size(mp)) /
> +		sizeof(xfs_dir2_data_off_t);
> +}
> +
> +static inline __be16 *
> +xfs_dir3_free_bests_p(struct xfs_mount *mp, struct xfs_dir2_free *free)
> +{
> +	return (__be16 *)((char *)free + xfs_dir3_free_hdr_size(mp));
> +}
> +
> +/*
> + * Convert data space db to the corresponding free db.
> + */
> +static inline xfs_dir2_db_t
> +xfs_dir2_db_to_fdb(struct xfs_mount *mp, xfs_dir2_db_t db)
> +{
> +	return XFS_DIR2_FREE_FIRSTDB(mp) + db / xfs_dir3_free_max_bests(mp);
> +}
> +
> +/*
> + * Convert data space db to the corresponding index in a free db.
> + */
> +static inline int
> +xfs_dir2_db_to_fdindex(struct xfs_mount *mp, xfs_dir2_db_t db)
> +{
> +	return db % xfs_dir3_free_max_bests(mp);
> +}
> +
> +/*
> + * Single block format.
> + *
> + * The single block format looks like the following drawing on disk:
> + *
> + *    +-------------------------------------------------+
> + *    | xfs_dir2_data_hdr_t                             |
> + *    +-------------------------------------------------+
> + *    | xfs_dir2_data_entry_t OR xfs_dir2_data_unused_t |
> + *    | xfs_dir2_data_entry_t OR xfs_dir2_data_unused_t |
> + *    | xfs_dir2_data_entry_t OR xfs_dir2_data_unused_t :
> + *    | ...                                             |
> + *    +-------------------------------------------------+
> + *    | unused space                                    |
> + *    +-------------------------------------------------+
> + *    | ...                                             |
> + *    | xfs_dir2_leaf_entry_t                           |
> + *    | xfs_dir2_leaf_entry_t                           |
> + *    +-------------------------------------------------+
> + *    | xfs_dir2_block_tail_t                           |
> + *    +-------------------------------------------------+
> + *
> + * As all the entries are variable size structures the accessors below should
> + * be used to iterate over them.
> + */
> +
> +typedef struct xfs_dir2_block_tail {
> +	__be32		count;			/* count of leaf entries */
> +	__be32		stale;			/* count of stale lf entries */
> +} xfs_dir2_block_tail_t;
> +
> +/*
> + * Pointer to the leaf header embedded in a data block (1-block format)
> + */
> +static inline struct xfs_dir2_block_tail *
> +xfs_dir2_block_tail_p(struct xfs_mount *mp, struct xfs_dir2_data_hdr *hdr)
> +{
> +	return ((struct xfs_dir2_block_tail *)
> +		((char *)hdr + mp->m_dirblksize)) - 1;
> +}
> +
> +/*
> + * Pointer to the leaf entries embedded in a data block (1-block format)
> + */
> +static inline struct xfs_dir2_leaf_entry *
> +xfs_dir2_block_leaf_p(struct xfs_dir2_block_tail *btp)
> +{
> +	return ((struct xfs_dir2_leaf_entry *)btp) - be32_to_cpu(btp->count);
> +}
> +
> +
> +/*
> + * Attribute storage layout
> + *
> + * Attribute lists are structured around Btrees where all the data
> + * elements are in the leaf nodes.  Attribute names are hashed into an int,
> + * then that int is used as the index into the Btree.  Since the hashval
> + * of an attribute name may not be unique, we may have duplicate keys.  The
> + * internal links in the Btree are logical block offsets into the file.
> + *
> + *========================================================================
> + * Attribute structure when equal to XFS_LBSIZE(mp) bytes.
> + *========================================================================
> + *
> + * Struct leaf_entry's are packed from the top.  Name/values grow from the
> + * bottom but are not packed.  The freemap contains run-length-encoded entries
> + * for the free bytes after the leaf_entry's, but only the N largest such,
> + * smaller runs are dropped.  When the freemap doesn't show enough space
> + * for an allocation, we compact the name/value area and try again.  If we
> + * still don't have enough space, then we have to split the block.  The
> + * name/value structs (both local and remote versions) must be 32bit aligned.
> + *
> + * Since we have duplicate hash keys, for each key that matches, compare
> + * the actual name string.  The root and intermediate node search always
> + * takes the first-in-the-block key match found, so we should only have
> + * to work "forw"ard.  If none matches, continue with the "forw"ard leaf
> + * nodes until the hash key changes or the attribute name is found.
> + *
> + * We store the fact that an attribute is a ROOT/USER/SECURE attribute in
> + * the leaf_entry.  The namespaces are independent only because we also look
> + * at the namespace bit when we are looking for a matching attribute name.
> + *
> + * We also store an "incomplete" bit in the leaf_entry.  It shows that an
> + * attribute is in the middle of being created and should not be shown to
> + * the user if we crash during the time that the bit is set.  We clear the
> + * bit when we have finished setting up the attribute.  We do this because
> + * we cannot create some large attributes inside a single transaction, and we
> + * need some indication that we weren't finished if we crash in the middle.
> + */
> +#define XFS_ATTR_LEAF_MAPSIZE	3	/* how many freespace slots */
> +
> +typedef struct xfs_attr_leaf_map {	/* RLE map of free bytes */
> +	__be16	base;			  /* base of free region */
> +	__be16	size;			  /* length of free region */
> +} xfs_attr_leaf_map_t;
> +
> +typedef struct xfs_attr_leaf_hdr {	/* constant-structure header block */
> +	xfs_da_blkinfo_t info;		/* block type, links, etc. */
> +	__be16	count;			/* count of active leaf_entry's */
> +	__be16	usedbytes;		/* num bytes of names/values stored */
> +	__be16	firstused;		/* first used byte in name area */
> +	__u8	holes;			/* != 0 if blk needs compaction */
> +	__u8	pad1;
> +	xfs_attr_leaf_map_t freemap[XFS_ATTR_LEAF_MAPSIZE];
> +					/* N largest free regions */
> +} xfs_attr_leaf_hdr_t;
> +
> +typedef struct xfs_attr_leaf_entry {	/* sorted on key, not name */
> +	__be32	hashval;		/* hash value of name */
> +	__be16	nameidx;		/* index into buffer of name/value */
> +	__u8	flags;			/* LOCAL/ROOT/SECURE/INCOMPLETE flag */
> +	__u8	pad2;			/* unused pad byte */
> +} xfs_attr_leaf_entry_t;
> +
> +typedef struct xfs_attr_leaf_name_local {
> +	__be16	valuelen;		/* number of bytes in value */
> +	__u8	namelen;		/* length of name bytes */
> +	__u8	nameval[1];		/* name/value bytes */
> +} xfs_attr_leaf_name_local_t;
> +
> +typedef struct xfs_attr_leaf_name_remote {
> +	__be32	valueblk;		/* block number of value bytes */
> +	__be32	valuelen;		/* number of bytes in value */
> +	__u8	namelen;		/* length of name bytes */
> +	__u8	name[1];		/* name bytes */
> +} xfs_attr_leaf_name_remote_t;
> +
> +typedef struct xfs_attr_leafblock {
> +	xfs_attr_leaf_hdr_t	hdr;	/* constant-structure header block */
> +	xfs_attr_leaf_entry_t	entries[1];	/* sorted on key, not name */
> +	xfs_attr_leaf_name_local_t namelist;	/* grows from bottom of buf */
> +	xfs_attr_leaf_name_remote_t valuelist;	/* grows from bottom of buf */
> +} xfs_attr_leafblock_t;
> +
> +/*
> + * CRC enabled leaf structures. Called "version 3" structures to match the
> + * version number of the directory and dablk structures for this feature, and
> + * attr2 is already taken by the variable inode attribute fork size feature.
> + */
> +struct xfs_attr3_leaf_hdr {
> +	struct xfs_da3_blkinfo	info;
> +	__be16			count;
> +	__be16			usedbytes;
> +	__be16			firstused;
> +	__u8			holes;
> +	__u8			pad1;
> +	struct xfs_attr_leaf_map freemap[XFS_ATTR_LEAF_MAPSIZE];
> +	__be32			pad2;		/* 64 bit alignment */
> +};
> +
> +#define XFS_ATTR3_LEAF_CRC_OFF	(offsetof(struct xfs_attr3_leaf_hdr, info.crc))
> +
> +struct xfs_attr3_leafblock {
> +	struct xfs_attr3_leaf_hdr	hdr;
> +	struct xfs_attr_leaf_entry	entries[1];
> +
> +	/*
> +	 * The rest of the block contains the following structures after the
> +	 * leaf entries, growing from the bottom up. The variables are never
> +	 * referenced, the locations accessed purely from helper functions.
> +	 *
> +	 * struct xfs_attr_leaf_name_local
> +	 * struct xfs_attr_leaf_name_remote
> +	 */
> +};
> +
> +/*
> + * incore, neutral version of the attribute leaf header
> + */
> +struct xfs_attr3_icleaf_hdr {
> +	__uint32_t	forw;
> +	__uint32_t	back;
> +	__uint16_t	magic;
> +	__uint16_t	count;
> +	__uint16_t	usedbytes;
> +	__uint16_t	firstused;
> +	__u8		holes;
> +	struct {
> +		__uint16_t	base;
> +		__uint16_t	size;
> +	} freemap[XFS_ATTR_LEAF_MAPSIZE];
> +};
> +
> +/*
> + * Flags used in the leaf_entry[i].flags field.
> + * NOTE: the INCOMPLETE bit must not collide with the flags bits specified
> + * on the system call, they are "or"ed together for various operations.
> + */
> +#define	XFS_ATTR_LOCAL_BIT	0	/* attr is stored locally */
> +#define	XFS_ATTR_ROOT_BIT	1	/* limit access to trusted attrs */
> +#define	XFS_ATTR_SECURE_BIT	2	/* limit access to secure attrs */
> +#define	XFS_ATTR_INCOMPLETE_BIT	7	/* attr in middle of create/delete */
> +#define XFS_ATTR_LOCAL		(1 << XFS_ATTR_LOCAL_BIT)
> +#define XFS_ATTR_ROOT		(1 << XFS_ATTR_ROOT_BIT)
> +#define XFS_ATTR_SECURE		(1 << XFS_ATTR_SECURE_BIT)
> +#define XFS_ATTR_INCOMPLETE	(1 << XFS_ATTR_INCOMPLETE_BIT)
> +
> +/*
> + * Conversion macros for converting namespace bits from argument flags
> + * to ondisk flags.
> + */
> +#define XFS_ATTR_NSP_ARGS_MASK		(ATTR_ROOT | ATTR_SECURE)
> +#define XFS_ATTR_NSP_ONDISK_MASK	(XFS_ATTR_ROOT | XFS_ATTR_SECURE)
> +#define XFS_ATTR_NSP_ONDISK(flags)	((flags) & XFS_ATTR_NSP_ONDISK_MASK)
> +#define XFS_ATTR_NSP_ARGS(flags)	((flags) & XFS_ATTR_NSP_ARGS_MASK)
> +#define XFS_ATTR_NSP_ARGS_TO_ONDISK(x)	(((x) & ATTR_ROOT ? XFS_ATTR_ROOT : 0) |\
> +					 ((x) & ATTR_SECURE ? XFS_ATTR_SECURE : 0))
> +#define XFS_ATTR_NSP_ONDISK_TO_ARGS(x)	(((x) & XFS_ATTR_ROOT ? ATTR_ROOT : 0) |\
> +					 ((x) & XFS_ATTR_SECURE ? ATTR_SECURE : 0))
> +
> +/*
> + * Alignment for namelist and valuelist entries (since they are mixed
> + * there can be only one alignment value)
> + */
> +#define	XFS_ATTR_LEAF_NAME_ALIGN	((uint)sizeof(xfs_dablk_t))
> +
> +static inline int
> +xfs_attr3_leaf_hdr_size(struct xfs_attr_leafblock *leafp)
> +{
> +	if (leafp->hdr.info.magic == cpu_to_be16(XFS_ATTR3_LEAF_MAGIC))
> +		return sizeof(struct xfs_attr3_leaf_hdr);
> +	return sizeof(struct xfs_attr_leaf_hdr);
> +}
> +
> +static inline struct xfs_attr_leaf_entry *
> +xfs_attr3_leaf_entryp(xfs_attr_leafblock_t *leafp)
> +{
> +	if (leafp->hdr.info.magic == cpu_to_be16(XFS_ATTR3_LEAF_MAGIC))
> +		return &((struct xfs_attr3_leafblock *)leafp)->entries[0];
> +	return &leafp->entries[0];
> +}
> +
> +/*
> + * Cast typed pointers for "local" and "remote" name/value structs.
> + */
> +static inline char *
> +xfs_attr3_leaf_name(xfs_attr_leafblock_t *leafp, int idx)
> +{
> +	struct xfs_attr_leaf_entry *entries = xfs_attr3_leaf_entryp(leafp);
> +
> +	return &((char *)leafp)[be16_to_cpu(entries[idx].nameidx)];
> +}
> +
> +static inline xfs_attr_leaf_name_remote_t *
> +xfs_attr3_leaf_name_remote(xfs_attr_leafblock_t *leafp, int idx)
> +{
> +	return (xfs_attr_leaf_name_remote_t *)xfs_attr3_leaf_name(leafp, idx);
> +}
> +
> +static inline xfs_attr_leaf_name_local_t *
> +xfs_attr3_leaf_name_local(xfs_attr_leafblock_t *leafp, int idx)
> +{
> +	return (xfs_attr_leaf_name_local_t *)xfs_attr3_leaf_name(leafp, idx);
> +}
> +
> +/*
> + * Calculate total bytes used (including trailing pad for alignment) for
> + * a "local" name/value structure, a "remote" name/value structure, and
> + * a pointer which might be either.
> + */
> +static inline int xfs_attr_leaf_entsize_remote(int nlen)
> +{
> +	return ((uint)sizeof(xfs_attr_leaf_name_remote_t) - 1 + (nlen) + \
> +		XFS_ATTR_LEAF_NAME_ALIGN - 1) & ~(XFS_ATTR_LEAF_NAME_ALIGN - 1);
> +}
> +
> +static inline int xfs_attr_leaf_entsize_local(int nlen, int vlen)
> +{
> +	return ((uint)sizeof(xfs_attr_leaf_name_local_t) - 1 + (nlen) + (vlen) +
> +		XFS_ATTR_LEAF_NAME_ALIGN - 1) & ~(XFS_ATTR_LEAF_NAME_ALIGN - 1);
> +}
> +
> +static inline int xfs_attr_leaf_entsize_local_max(int bsize)
> +{
> +	return (((bsize) >> 1) + ((bsize) >> 2));
> +}
> +
> +
> +
> +/*
> + * Remote attribute block format definition
> + *
> + * There is one of these headers per filesystem block in a remote attribute.
> + * This is done to ensure there is a 1:1 mapping between the attribute value
> + * length and the number of blocks needed to store the attribute. This makes the
> + * verification of a buffer a little more complex, but greatly simplifies the
> + * allocation, reading and writing of these attributes as we don't have to guess
> + * the number of blocks needed to store the attribute data.
> + */
> +#define XFS_ATTR3_RMT_MAGIC	0x5841524d	/* XARM */
> +
> +struct xfs_attr3_rmt_hdr {
> +	__be32	rm_magic;
> +	__be32	rm_offset;
> +	__be32	rm_bytes;
> +	__be32	rm_crc;
> +	uuid_t	rm_uuid;
> +	__be64	rm_owner;
> +	__be64	rm_blkno;
> +	__be64	rm_lsn;
> +};
> +
> +#define XFS_ATTR3_RMT_CRC_OFF	offsetof(struct xfs_attr3_rmt_hdr, rm_crc)
> +
> +#define XFS_ATTR3_RMT_BUF_SPACE(mp, bufsize)	\
> +	((bufsize) - (xfs_sb_version_hascrc(&(mp)->m_sb) ? \
> +			sizeof(struct xfs_attr3_rmt_hdr) : 0))
> +
> +#endif /* __XFS_DA_FORMAT_H__ */
> diff --git a/include/xfs_dir2_format.h b/include/xfs_dir2_format.h
> deleted file mode 100644
> index 9cf6738..0000000
> --- a/include/xfs_dir2_format.h
> +++ /dev/null
> @@ -1,964 +0,0 @@
> -/*
> - * Copyright (c) 2000-2001,2005 Silicon Graphics, Inc.
> - * Copyright (c) 2013 Red Hat, 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_DIR2_FORMAT_H__
> -#define __XFS_DIR2_FORMAT_H__
> -
> -/*
> - * Directory version 2.
> - *
> - * There are 4 possible formats:
> - *  - shortform - embedded into the inode
> - *  - single block - data with embedded leaf at the end
> - *  - multiple data blocks, single leaf+freeindex block
> - *  - data blocks, node and leaf blocks (btree), freeindex blocks
> - *
> - * Note: many node blocks structures and constants are shared with the attr
> - * code and defined in xfs_da_btree.h.
> - */
> -
> -#define	XFS_DIR2_BLOCK_MAGIC	0x58443242	/* XD2B: single block dirs */
> -#define	XFS_DIR2_DATA_MAGIC	0x58443244	/* XD2D: multiblock dirs */
> -#define	XFS_DIR2_FREE_MAGIC	0x58443246	/* XD2F: free index blocks */
> -
> -/*
> - * Directory Version 3 With CRCs.
> - *
> - * The tree formats are the same as for version 2 directories.  The difference
> - * is in the block header and dirent formats. In many cases the v3 structures
> - * use v2 definitions as they are no different and this makes code sharing much
> - * easier.
> - *
> - * Also, the xfs_dir3_*() functions handle both v2 and v3 formats - if the
> - * format is v2 then they switch to the existing v2 code, or the format is v3
> - * they implement the v3 functionality. This means the existing dir2 is a mix of
> - * xfs_dir2/xfs_dir3 calls and functions. The xfs_dir3 functions are called
> - * where there is a difference in the formats, otherwise the code is unchanged.
> - *
> - * Where it is possible, the code decides what to do based on the magic numbers
> - * in the blocks rather than feature bits in the superblock. This means the code
> - * is as independent of the external XFS code as possible as doesn't require
> - * passing struct xfs_mount pointers into places where it isn't really
> - * necessary.
> - *
> - * Version 3 includes:
> - *
> - *	- a larger block header for CRC and identification purposes and so the
> - *	offsets of all the structures inside the blocks are different.
> - *
> - *	- new magic numbers to be able to detect the v2/v3 types on the fly.
> - */
> -
> -#define	XFS_DIR3_BLOCK_MAGIC	0x58444233	/* XDB3: single block dirs */
> -#define	XFS_DIR3_DATA_MAGIC	0x58444433	/* XDD3: multiblock dirs */
> -#define	XFS_DIR3_FREE_MAGIC	0x58444633	/* XDF3: free index blocks */
> -
> -/*
> - * Dirents in version 3 directories have a file type field. Additions to this
> - * list are an on-disk format change, requiring feature bits. Valid values
> - * are as follows:
> - */
> -#define XFS_DIR3_FT_UNKNOWN		0
> -#define XFS_DIR3_FT_REG_FILE		1
> -#define XFS_DIR3_FT_DIR			2
> -#define XFS_DIR3_FT_CHRDEV		3
> -#define XFS_DIR3_FT_BLKDEV		4
> -#define XFS_DIR3_FT_FIFO		5
> -#define XFS_DIR3_FT_SOCK		6
> -#define XFS_DIR3_FT_SYMLINK		7
> -#define XFS_DIR3_FT_WHT			8
> -
> -#define XFS_DIR3_FT_MAX			9
> -
> -/*
> - * Byte offset in data block and shortform entry.
> - */
> -typedef	__uint16_t	xfs_dir2_data_off_t;
> -#define	NULLDATAOFF	0xffffU
> -typedef uint		xfs_dir2_data_aoff_t;	/* argument form */
> -
> -/*
> - * Normalized offset (in a data block) of the entry, really xfs_dir2_data_off_t.
> - * Only need 16 bits, this is the byte offset into the single block form.
> - */
> -typedef struct { __uint8_t i[2]; } __arch_pack xfs_dir2_sf_off_t;
> -
> -/*
> - * Offset in data space of a data entry.
> - */
> -typedef	__uint32_t	xfs_dir2_dataptr_t;
> -#define	XFS_DIR2_MAX_DATAPTR	((xfs_dir2_dataptr_t)0xffffffff)
> -#define	XFS_DIR2_NULL_DATAPTR	((xfs_dir2_dataptr_t)0)
> -
> -/*
> - * Byte offset in a directory.
> - */
> -typedef	xfs_off_t	xfs_dir2_off_t;
> -
> -/*
> - * Directory block number (logical dirblk in file)
> - */
> -typedef	__uint32_t	xfs_dir2_db_t;
> -
> -/*
> - * Inode number stored as 8 8-bit values.
> - */
> -typedef	struct { __uint8_t i[8]; } xfs_dir2_ino8_t;
> -
> -/*
> - * Inode number stored as 4 8-bit values.
> - * Works a lot of the time, when all the inode numbers in a directory
> - * fit in 32 bits.
> - */
> -typedef struct { __uint8_t i[4]; } xfs_dir2_ino4_t;
> -
> -typedef union {
> -	xfs_dir2_ino8_t	i8;
> -	xfs_dir2_ino4_t	i4;
> -} xfs_dir2_inou_t;
> -#define	XFS_DIR2_MAX_SHORT_INUM	((xfs_ino_t)0xffffffffULL)
> -
> -/*
> - * Directory layout when stored internal to an inode.
> - *
> - * Small directories are packed as tightly as possible so as to fit into the
> - * literal area of the inode.  These "shortform" directories consist of a
> - * single xfs_dir2_sf_hdr header followed by zero or more xfs_dir2_sf_entry
> - * structures.  Due the different inode number storage size and the variable
> - * length name field in the xfs_dir2_sf_entry all these structure are
> - * variable length, and the accessors in this file should be used to iterate
> - * over them.
> - */
> -typedef struct xfs_dir2_sf_hdr {
> -	__uint8_t		count;		/* count of entries */
> -	__uint8_t		i8count;	/* count of 8-byte inode #s */
> -	xfs_dir2_inou_t		parent;		/* parent dir inode number */
> -} __arch_pack xfs_dir2_sf_hdr_t;
> -
> -typedef struct xfs_dir2_sf_entry {
> -	__u8			namelen;	/* actual name length */
> -	xfs_dir2_sf_off_t	offset;		/* saved offset */
> -	__u8			name[];		/* name, variable size */
> -	/*
> -	 * A single byte containing the file type field follows the inode
> -	 * number for version 3 directory entries.
> -	 *
> -	 * A xfs_dir2_ino8_t or xfs_dir2_ino4_t follows here, at a
> -	 * variable offset after the name.
> -	 */
> -} __arch_pack xfs_dir2_sf_entry_t;
> -
> -static inline int xfs_dir2_sf_hdr_size(int i8count)
> -{
> -	return sizeof(struct xfs_dir2_sf_hdr) -
> -		(i8count == 0) *
> -		(sizeof(xfs_dir2_ino8_t) - sizeof(xfs_dir2_ino4_t));
> -}
> -
> -static inline xfs_dir2_data_aoff_t
> -xfs_dir2_sf_get_offset(xfs_dir2_sf_entry_t *sfep)
> -{
> -	return get_unaligned_be16(&sfep->offset.i);
> -}
> -
> -static inline void
> -xfs_dir2_sf_put_offset(xfs_dir2_sf_entry_t *sfep, xfs_dir2_data_aoff_t off)
> -{
> -	put_unaligned_be16(off, &sfep->offset.i);
> -}
> -
> -static inline struct xfs_dir2_sf_entry *
> -xfs_dir2_sf_firstentry(struct xfs_dir2_sf_hdr *hdr)
> -{
> -	return (struct xfs_dir2_sf_entry *)
> -		((char *)hdr + xfs_dir2_sf_hdr_size(hdr->i8count));
> -}
> -
> -static inline int
> -xfs_dir3_sf_entsize(
> -	struct xfs_mount	*mp,
> -	struct xfs_dir2_sf_hdr	*hdr,
> -	int			len)
> -{
> -	int count = sizeof(struct xfs_dir2_sf_entry); 	/* namelen + offset */
> -
> -	count += len;					/* name */
> -	count += hdr->i8count ? sizeof(xfs_dir2_ino8_t) :
> -				sizeof(xfs_dir2_ino4_t); /* ino # */
> -	if (xfs_sb_version_hasftype(&mp->m_sb))
> -		count += sizeof(__uint8_t);		/* file type */
> -	return count;
> -}
> -
> -static inline struct xfs_dir2_sf_entry *
> -xfs_dir3_sf_nextentry(
> -	struct xfs_mount	*mp,
> -	struct xfs_dir2_sf_hdr	*hdr,
> -	struct xfs_dir2_sf_entry *sfep)
> -{
> -	return (struct xfs_dir2_sf_entry *)
> -		((char *)sfep + xfs_dir3_sf_entsize(mp, hdr, sfep->namelen));
> -}
> -
> -/*
> - * in dir3 shortform directories, the file type field is stored at a variable
> - * offset after the inode number. Because it's only a single byte, endian
> - * conversion is not necessary.
> - */
> -static inline __uint8_t *
> -xfs_dir3_sfe_ftypep(
> -	struct xfs_dir2_sf_hdr	*hdr,
> -	struct xfs_dir2_sf_entry *sfep)
> -{
> -	return (__uint8_t *)&sfep->name[sfep->namelen];
> -}
> -
> -static inline __uint8_t
> -xfs_dir3_sfe_get_ftype(
> -	struct xfs_mount	*mp,
> -	struct xfs_dir2_sf_hdr	*hdr,
> -	struct xfs_dir2_sf_entry *sfep)
> -{
> -	__uint8_t	*ftp;
> -
> -	if (!xfs_sb_version_hasftype(&mp->m_sb))
> -		return XFS_DIR3_FT_UNKNOWN;
> -
> -	ftp = xfs_dir3_sfe_ftypep(hdr, sfep);
> -	if (*ftp >= XFS_DIR3_FT_MAX)
> -		return XFS_DIR3_FT_UNKNOWN;
> -	return *ftp;
> -}
> -
> -static inline void
> -xfs_dir3_sfe_put_ftype(
> -	struct xfs_mount	*mp,
> -	struct xfs_dir2_sf_hdr	*hdr,
> -	struct xfs_dir2_sf_entry *sfep,
> -	__uint8_t		ftype)
> -{
> -	__uint8_t	*ftp;
> -
> -	ASSERT(ftype < XFS_DIR3_FT_MAX);
> -
> -	if (!xfs_sb_version_hasftype(&mp->m_sb))
> -		return;
> -	ftp = xfs_dir3_sfe_ftypep(hdr, sfep);
> -	*ftp = ftype;
> -}
> -
> -/*
> - * Data block structures.
> - *
> - * A pure data block looks like the following drawing on disk:
> - *
> - *    +-------------------------------------------------+
> - *    | xfs_dir2_data_hdr_t                             |
> - *    +-------------------------------------------------+
> - *    | xfs_dir2_data_entry_t OR xfs_dir2_data_unused_t |
> - *    | xfs_dir2_data_entry_t OR xfs_dir2_data_unused_t |
> - *    | xfs_dir2_data_entry_t OR xfs_dir2_data_unused_t |
> - *    | ...                                             |
> - *    +-------------------------------------------------+
> - *    | unused space                                    |
> - *    +-------------------------------------------------+
> - *
> - * As all the entries are variable size structures the accessors below should
> - * be used to iterate over them.
> - *
> - * In addition to the pure data blocks for the data and node formats,
> - * most structures are also used for the combined data/freespace "block"
> - * format below.
> - */
> -
> -#define	XFS_DIR2_DATA_ALIGN_LOG	3		/* i.e., 8 bytes */
> -#define	XFS_DIR2_DATA_ALIGN	(1 << XFS_DIR2_DATA_ALIGN_LOG)
> -#define	XFS_DIR2_DATA_FREE_TAG	0xffff
> -#define	XFS_DIR2_DATA_FD_COUNT	3
> -
> -/*
> - * Directory address space divided into sections,
> - * spaces separated by 32GB.
> - */
> -#define	XFS_DIR2_SPACE_SIZE	(1ULL << (32 + XFS_DIR2_DATA_ALIGN_LOG))
> -#define	XFS_DIR2_DATA_SPACE	0
> -#define	XFS_DIR2_DATA_OFFSET	(XFS_DIR2_DATA_SPACE * XFS_DIR2_SPACE_SIZE)
> -#define	XFS_DIR2_DATA_FIRSTDB(mp)	\
> -	xfs_dir2_byte_to_db(mp, XFS_DIR2_DATA_OFFSET)
> -
> -/*
> - * Describe a free area in the data block.
> - *
> - * The freespace will be formatted as a xfs_dir2_data_unused_t.
> - */
> -typedef struct xfs_dir2_data_free {
> -	__be16			offset;		/* start of freespace */
> -	__be16			length;		/* length of freespace */
> -} xfs_dir2_data_free_t;
> -
> -/*
> - * Header for the data blocks.
> - *
> - * The code knows that XFS_DIR2_DATA_FD_COUNT is 3.
> - */
> -typedef struct xfs_dir2_data_hdr {
> -	__be32			magic;		/* XFS_DIR2_DATA_MAGIC or */
> -						/* XFS_DIR2_BLOCK_MAGIC */
> -	xfs_dir2_data_free_t	bestfree[XFS_DIR2_DATA_FD_COUNT];
> -} xfs_dir2_data_hdr_t;
> -
> -/*
> - * define a structure for all the verification fields we are adding to the
> - * directory block structures. This will be used in several structures.
> - * The magic number must be the first entry to align with all the dir2
> - * structures so we determine how to decode them just by the magic number.
> - */
> -struct xfs_dir3_blk_hdr {
> -	__be32			magic;	/* magic number */
> -	__be32			crc;	/* CRC of block */
> -	__be64			blkno;	/* first block of the buffer */
> -	__be64			lsn;	/* sequence number of last write */
> -	uuid_t			uuid;	/* filesystem we belong to */
> -	__be64			owner;	/* inode that owns the block */
> -};
> -
> -struct xfs_dir3_data_hdr {
> -	struct xfs_dir3_blk_hdr	hdr;
> -	xfs_dir2_data_free_t	best_free[XFS_DIR2_DATA_FD_COUNT];
> -	__be32			pad;	/* 64 bit alignment */
> -};
> -
> -#define XFS_DIR3_DATA_CRC_OFF  offsetof(struct xfs_dir3_data_hdr, hdr.crc)
> -
> -static inline struct xfs_dir2_data_free *
> -xfs_dir3_data_bestfree_p(struct xfs_dir2_data_hdr *hdr)
> -{
> -	if (hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC) ||
> -	    hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC)) {
> -		struct xfs_dir3_data_hdr *hdr3 = (struct xfs_dir3_data_hdr *)hdr;
> -		return hdr3->best_free;
> -	}
> -	return hdr->bestfree;
> -}
> -
> -/*
> - * Active entry in a data block.
> - *
> - * Aligned to 8 bytes.  After the variable length name field there is a
> - * 2 byte tag field, which can be accessed using xfs_dir3_data_entry_tag_p.
> - *
> - * For dir3 structures, there is file type field between the name and the tag.
> - * This can only be manipulated by helper functions. It is packed hard against
> - * the end of the name so any padding for rounding is between the file type and
> - * the tag.
> - */
> -typedef struct xfs_dir2_data_entry {
> -	__be64			inumber;	/* inode number */
> -	__u8			namelen;	/* name length */
> -	__u8			name[];		/* name bytes, no null */
> -     /* __u8			filetype; */	/* type of inode we point to */
> -     /*	__be16                  tag; */		/* starting offset of us */
> -} xfs_dir2_data_entry_t;
> -
> -/*
> - * Unused entry in a data block.
> - *
> - * Aligned to 8 bytes.  Tag appears as the last 2 bytes and must be accessed
> - * using xfs_dir2_data_unused_tag_p.
> - */
> -typedef struct xfs_dir2_data_unused {
> -	__be16			freetag;	/* XFS_DIR2_DATA_FREE_TAG */
> -	__be16			length;		/* total free length */
> -						/* variable offset */
> -	__be16			tag;		/* starting offset of us */
> -} xfs_dir2_data_unused_t;
> -
> -/*
> - * Size of a data entry.
> - */
> -static inline int
> -__xfs_dir3_data_entsize(
> -	bool	ftype,
> -	int	n)
> -{
> -	int	size = offsetof(struct xfs_dir2_data_entry, name[0]);
> -
> -	size += n;
> -	size += sizeof(xfs_dir2_data_off_t);
> -	if (ftype)
> -		size += sizeof(__uint8_t);
> -	return roundup(size, XFS_DIR2_DATA_ALIGN);
> -}
> -static inline int
> -xfs_dir3_data_entsize(
> -	struct xfs_mount	*mp,
> -	int			n)
> -{
> -	bool ftype = xfs_sb_version_hasftype(&mp->m_sb) ? true : false;
> -	return __xfs_dir3_data_entsize(ftype, n);
> -}
> -
> -static inline __uint8_t
> -xfs_dir3_dirent_get_ftype(
> -	struct xfs_mount	*mp,
> -	struct xfs_dir2_data_entry *dep)
> -{
> -	if (xfs_sb_version_hasftype(&mp->m_sb)) {
> -		__uint8_t	type = dep->name[dep->namelen];
> -
> -		ASSERT(type < XFS_DIR3_FT_MAX);
> -		if (type < XFS_DIR3_FT_MAX)
> -			return type;
> -
> -	}
> -	return XFS_DIR3_FT_UNKNOWN;
> -}
> -
> -static inline void
> -xfs_dir3_dirent_put_ftype(
> -	struct xfs_mount	*mp,
> -	struct xfs_dir2_data_entry *dep,
> -	__uint8_t		type)
> -{
> -	ASSERT(type < XFS_DIR3_FT_MAX);
> -	ASSERT(dep->namelen != 0);
> -
> -	if (xfs_sb_version_hasftype(&mp->m_sb))
> -		dep->name[dep->namelen] = type;
> -}
> -
> -/*
> - * Pointer to an entry's tag word.
> - */
> -static inline __be16 *
> -xfs_dir3_data_entry_tag_p(
> -	struct xfs_mount	*mp,
> -	struct xfs_dir2_data_entry *dep)
> -{
> -	return (__be16 *)((char *)dep +
> -		xfs_dir3_data_entsize(mp, dep->namelen) - sizeof(__be16));
> -}
> -
> -/*
> - * Pointer to a freespace's tag word.
> - */
> -static inline __be16 *
> -xfs_dir2_data_unused_tag_p(struct xfs_dir2_data_unused *dup)
> -{
> -	return (__be16 *)((char *)dup +
> -			be16_to_cpu(dup->length) - sizeof(__be16));
> -}
> -
> -static inline size_t
> -xfs_dir3_data_hdr_size(bool dir3)
> -{
> -	if (dir3)
> -		return sizeof(struct xfs_dir3_data_hdr);
> -	return sizeof(struct xfs_dir2_data_hdr);
> -}
> -
> -static inline size_t
> -xfs_dir3_data_entry_offset(struct xfs_dir2_data_hdr *hdr)
> -{
> -	bool dir3 = hdr->magic == cpu_to_be32(XFS_DIR3_DATA_MAGIC) ||
> -		    hdr->magic == cpu_to_be32(XFS_DIR3_BLOCK_MAGIC);
> -	return xfs_dir3_data_hdr_size(dir3);
> -}
> -
> -static inline struct xfs_dir2_data_entry *
> -xfs_dir3_data_entry_p(struct xfs_dir2_data_hdr *hdr)
> -{
> -	return (struct xfs_dir2_data_entry *)
> -		((char *)hdr + xfs_dir3_data_entry_offset(hdr));
> -}
> -
> -static inline struct xfs_dir2_data_unused *
> -xfs_dir3_data_unused_p(struct xfs_dir2_data_hdr *hdr)
> -{
> -	return (struct xfs_dir2_data_unused *)
> -		((char *)hdr + xfs_dir3_data_entry_offset(hdr));
> -}
> -
> -/*
> - * Offsets of . and .. in data space (always block 0)
> - *
> - * XXX: there is scope for significant optimisation of the logic here. Right
> - * now we are checking for "dir3 format" over and over again. Ideally we should
> - * only do it once for each operation.
> - */
> -static inline xfs_dir2_data_aoff_t
> -xfs_dir3_data_dot_offset(struct xfs_mount *mp)
> -{
> -	return xfs_dir3_data_hdr_size(xfs_sb_version_hascrc(&mp->m_sb));
> -}
> -
> -static inline xfs_dir2_data_aoff_t
> -xfs_dir3_data_dotdot_offset(struct xfs_mount *mp)
> -{
> -	return xfs_dir3_data_dot_offset(mp) +
> -		xfs_dir3_data_entsize(mp, 1);
> -}
> -
> -static inline xfs_dir2_data_aoff_t
> -xfs_dir3_data_first_offset(struct xfs_mount *mp)
> -{
> -	return xfs_dir3_data_dotdot_offset(mp) +
> -		xfs_dir3_data_entsize(mp, 2);
> -}
> -
> -/*
> - * location of . and .. in data space (always block 0)
> - */
> -static inline struct xfs_dir2_data_entry *
> -xfs_dir3_data_dot_entry_p(
> -	struct xfs_mount	*mp,
> -	struct xfs_dir2_data_hdr *hdr)
> -{
> -	return (struct xfs_dir2_data_entry *)
> -		((char *)hdr + xfs_dir3_data_dot_offset(mp));
> -}
> -
> -static inline struct xfs_dir2_data_entry *
> -xfs_dir3_data_dotdot_entry_p(
> -	struct xfs_mount	*mp,
> -	struct xfs_dir2_data_hdr *hdr)
> -{
> -	return (struct xfs_dir2_data_entry *)
> -		((char *)hdr + xfs_dir3_data_dotdot_offset(mp));
> -}
> -
> -static inline struct xfs_dir2_data_entry *
> -xfs_dir3_data_first_entry_p(
> -	struct xfs_mount	*mp,
> -	struct xfs_dir2_data_hdr *hdr)
> -{
> -	return (struct xfs_dir2_data_entry *)
> -		((char *)hdr + xfs_dir3_data_first_offset(mp));
> -}
> -
> -/*
> - * Leaf block structures.
> - *
> - * A pure leaf block looks like the following drawing on disk:
> - *
> - *    +---------------------------+
> - *    | xfs_dir2_leaf_hdr_t       |
> - *    +---------------------------+
> - *    | xfs_dir2_leaf_entry_t     |
> - *    | xfs_dir2_leaf_entry_t     |
> - *    | xfs_dir2_leaf_entry_t     |
> - *    | xfs_dir2_leaf_entry_t     |
> - *    | ...                       |
> - *    +---------------------------+
> - *    | xfs_dir2_data_off_t       |
> - *    | xfs_dir2_data_off_t       |
> - *    | xfs_dir2_data_off_t       |
> - *    | ...                       |
> - *    +---------------------------+
> - *    | xfs_dir2_leaf_tail_t      |
> - *    +---------------------------+
> - *
> - * The xfs_dir2_data_off_t members (bests) and tail are at the end of the block
> - * for single-leaf (magic = XFS_DIR2_LEAF1_MAGIC) blocks only, but not present
> - * for directories with separate leaf nodes and free space blocks
> - * (magic = XFS_DIR2_LEAFN_MAGIC).
> - *
> - * As all the entries are variable size structures the accessors below should
> - * be used to iterate over them.
> - */
> -
> -/*
> - * Offset of the leaf/node space.  First block in this space
> - * is the btree root.
> - */
> -#define	XFS_DIR2_LEAF_SPACE	1
> -#define	XFS_DIR2_LEAF_OFFSET	(XFS_DIR2_LEAF_SPACE * XFS_DIR2_SPACE_SIZE)
> -#define	XFS_DIR2_LEAF_FIRSTDB(mp)	\
> -	xfs_dir2_byte_to_db(mp, XFS_DIR2_LEAF_OFFSET)
> -
> -/*
> - * Leaf block header.
> - */
> -typedef struct xfs_dir2_leaf_hdr {
> -	xfs_da_blkinfo_t	info;		/* header for da routines */
> -	__be16			count;		/* count of entries */
> -	__be16			stale;		/* count of stale entries */
> -} xfs_dir2_leaf_hdr_t;
> -
> -struct xfs_dir3_leaf_hdr {
> -	struct xfs_da3_blkinfo	info;		/* header for da routines */
> -	__be16			count;		/* count of entries */
> -	__be16			stale;		/* count of stale entries */
> -	__be32			pad;		/* 64 bit alignment */
> -};
> -
> -struct xfs_dir3_icleaf_hdr {
> -	__uint32_t		forw;
> -	__uint32_t		back;
> -	__uint16_t		magic;
> -	__uint16_t		count;
> -	__uint16_t		stale;
> -};
> -
> -/*
> - * Leaf block entry.
> - */
> -typedef struct xfs_dir2_leaf_entry {
> -	__be32			hashval;	/* hash value of name */
> -	__be32			address;	/* address of data entry */
> -} xfs_dir2_leaf_entry_t;
> -
> -/*
> - * Leaf block tail.
> - */
> -typedef struct xfs_dir2_leaf_tail {
> -	__be32			bestcount;
> -} xfs_dir2_leaf_tail_t;
> -
> -/*
> - * Leaf block.
> - */
> -typedef struct xfs_dir2_leaf {
> -	xfs_dir2_leaf_hdr_t	hdr;			/* leaf header */
> -	xfs_dir2_leaf_entry_t	__ents[];		/* entries */
> -} xfs_dir2_leaf_t;
> -
> -struct xfs_dir3_leaf {
> -	struct xfs_dir3_leaf_hdr	hdr;		/* leaf header */
> -	struct xfs_dir2_leaf_entry	__ents[];	/* entries */
> -};
> -
> -#define XFS_DIR3_LEAF_CRC_OFF  offsetof(struct xfs_dir3_leaf_hdr, info.crc)
> -
> -extern void xfs_dir3_leaf_hdr_from_disk(struct xfs_dir3_icleaf_hdr *to,
> -					struct xfs_dir2_leaf *from);
> -
> -static inline int
> -xfs_dir3_leaf_hdr_size(struct xfs_dir2_leaf *lp)
> -{
> -	if (lp->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAF1_MAGIC) ||
> -	    lp->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAFN_MAGIC))
> -		return sizeof(struct xfs_dir3_leaf_hdr);
> -	return sizeof(struct xfs_dir2_leaf_hdr);
> -}
> -
> -static inline int
> -xfs_dir3_max_leaf_ents(struct xfs_mount *mp, struct xfs_dir2_leaf *lp)
> -{
> -	return (mp->m_dirblksize - xfs_dir3_leaf_hdr_size(lp)) /
> -		(uint)sizeof(struct xfs_dir2_leaf_entry);
> -}
> -
> -/*
> - * Get address of the bestcount field in the single-leaf block.
> - */
> -static inline struct xfs_dir2_leaf_entry *
> -xfs_dir3_leaf_ents_p(struct xfs_dir2_leaf *lp)
> -{
> -	if (lp->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAF1_MAGIC) ||
> -	    lp->hdr.info.magic == cpu_to_be16(XFS_DIR3_LEAFN_MAGIC)) {
> -		struct xfs_dir3_leaf *lp3 = (struct xfs_dir3_leaf *)lp;
> -		return lp3->__ents;
> -	}
> -	return lp->__ents;
> -}
> -
> -/*
> - * Get address of the bestcount field in the single-leaf block.
> - */
> -static inline struct xfs_dir2_leaf_tail *
> -xfs_dir2_leaf_tail_p(struct xfs_mount *mp, struct xfs_dir2_leaf *lp)
> -{
> -	return (struct xfs_dir2_leaf_tail *)
> -		((char *)lp + mp->m_dirblksize -
> -		  sizeof(struct xfs_dir2_leaf_tail));
> -}
> -
> -/*
> - * Get address of the bests array in the single-leaf block.
> - */
> -static inline __be16 *
> -xfs_dir2_leaf_bests_p(struct xfs_dir2_leaf_tail *ltp)
> -{
> -	return (__be16 *)ltp - be32_to_cpu(ltp->bestcount);
> -}
> -
> -/*
> - * DB blocks here are logical directory block numbers, not filesystem blocks.
> - */
> -
> -/*
> - * Convert dataptr to byte in file space
> - */
> -static inline xfs_dir2_off_t
> -xfs_dir2_dataptr_to_byte(struct xfs_mount *mp, xfs_dir2_dataptr_t dp)
> -{
> -	return (xfs_dir2_off_t)dp << XFS_DIR2_DATA_ALIGN_LOG;
> -}
> -
> -/*
> - * Convert byte in file space to dataptr.  It had better be aligned.
> - */
> -static inline xfs_dir2_dataptr_t
> -xfs_dir2_byte_to_dataptr(struct xfs_mount *mp, xfs_dir2_off_t by)
> -{
> -	return (xfs_dir2_dataptr_t)(by >> XFS_DIR2_DATA_ALIGN_LOG);
> -}
> -
> -/*
> - * Convert byte in space to (DB) block
> - */
> -static inline xfs_dir2_db_t
> -xfs_dir2_byte_to_db(struct xfs_mount *mp, xfs_dir2_off_t by)
> -{
> -	return (xfs_dir2_db_t)
> -		(by >> (mp->m_sb.sb_blocklog + mp->m_sb.sb_dirblklog));
> -}
> -
> -/*
> - * Convert dataptr to a block number
> - */
> -static inline xfs_dir2_db_t
> -xfs_dir2_dataptr_to_db(struct xfs_mount *mp, xfs_dir2_dataptr_t dp)
> -{
> -	return xfs_dir2_byte_to_db(mp, xfs_dir2_dataptr_to_byte(mp, dp));
> -}
> -
> -/*
> - * Convert byte in space to offset in a block
> - */
> -static inline xfs_dir2_data_aoff_t
> -xfs_dir2_byte_to_off(struct xfs_mount *mp, xfs_dir2_off_t by)
> -{
> -	return (xfs_dir2_data_aoff_t)(by &
> -		((1 << (mp->m_sb.sb_blocklog + mp->m_sb.sb_dirblklog)) - 1));
> -}
> -
> -/*
> - * Convert dataptr to a byte offset in a block
> - */
> -static inline xfs_dir2_data_aoff_t
> -xfs_dir2_dataptr_to_off(struct xfs_mount *mp, xfs_dir2_dataptr_t dp)
> -{
> -	return xfs_dir2_byte_to_off(mp, xfs_dir2_dataptr_to_byte(mp, dp));
> -}
> -
> -/*
> - * Convert block and offset to byte in space
> - */
> -static inline xfs_dir2_off_t
> -xfs_dir2_db_off_to_byte(struct xfs_mount *mp, xfs_dir2_db_t db,
> -			xfs_dir2_data_aoff_t o)
> -{
> -	return ((xfs_dir2_off_t)db <<
> -		(mp->m_sb.sb_blocklog + mp->m_sb.sb_dirblklog)) + o;
> -}
> -
> -/*
> - * Convert block (DB) to block (dablk)
> - */
> -static inline xfs_dablk_t
> -xfs_dir2_db_to_da(struct xfs_mount *mp, xfs_dir2_db_t db)
> -{
> -	return (xfs_dablk_t)(db << mp->m_sb.sb_dirblklog);
> -}
> -
> -/*
> - * Convert byte in space to (DA) block
> - */
> -static inline xfs_dablk_t
> -xfs_dir2_byte_to_da(struct xfs_mount *mp, xfs_dir2_off_t by)
> -{
> -	return xfs_dir2_db_to_da(mp, xfs_dir2_byte_to_db(mp, by));
> -}
> -
> -/*
> - * Convert block and offset to dataptr
> - */
> -static inline xfs_dir2_dataptr_t
> -xfs_dir2_db_off_to_dataptr(struct xfs_mount *mp, xfs_dir2_db_t db,
> -			   xfs_dir2_data_aoff_t o)
> -{
> -	return xfs_dir2_byte_to_dataptr(mp, xfs_dir2_db_off_to_byte(mp, db, o));
> -}
> -
> -/*
> - * Convert block (dablk) to block (DB)
> - */
> -static inline xfs_dir2_db_t
> -xfs_dir2_da_to_db(struct xfs_mount *mp, xfs_dablk_t da)
> -{
> -	return (xfs_dir2_db_t)(da >> mp->m_sb.sb_dirblklog);
> -}
> -
> -/*
> - * Convert block (dablk) to byte offset in space
> - */
> -static inline xfs_dir2_off_t
> -xfs_dir2_da_to_byte(struct xfs_mount *mp, xfs_dablk_t da)
> -{
> -	return xfs_dir2_db_off_to_byte(mp, xfs_dir2_da_to_db(mp, da), 0);
> -}
> -
> -/*
> - * Free space block defintions for the node format.
> - */
> -
> -/*
> - * Offset of the freespace index.
> - */
> -#define	XFS_DIR2_FREE_SPACE	2
> -#define	XFS_DIR2_FREE_OFFSET	(XFS_DIR2_FREE_SPACE * XFS_DIR2_SPACE_SIZE)
> -#define	XFS_DIR2_FREE_FIRSTDB(mp)	\
> -	xfs_dir2_byte_to_db(mp, XFS_DIR2_FREE_OFFSET)
> -
> -typedef	struct xfs_dir2_free_hdr {
> -	__be32			magic;		/* XFS_DIR2_FREE_MAGIC */
> -	__be32			firstdb;	/* db of first entry */
> -	__be32			nvalid;		/* count of valid entries */
> -	__be32			nused;		/* count of used entries */
> -} xfs_dir2_free_hdr_t;
> -
> -typedef struct xfs_dir2_free {
> -	xfs_dir2_free_hdr_t	hdr;		/* block header */
> -	__be16			bests[];	/* best free counts */
> -						/* unused entries are -1 */
> -} xfs_dir2_free_t;
> -
> -struct xfs_dir3_free_hdr {
> -	struct xfs_dir3_blk_hdr	hdr;
> -	__be32			firstdb;	/* db of first entry */
> -	__be32			nvalid;		/* count of valid entries */
> -	__be32			nused;		/* count of used entries */
> -	__be32			pad;		/* 64 bit alignment */
> -};
> -
> -struct xfs_dir3_free {
> -	struct xfs_dir3_free_hdr hdr;
> -	__be16			bests[];	/* best free counts */
> -						/* unused entries are -1 */
> -};
> -
> -#define XFS_DIR3_FREE_CRC_OFF  offsetof(struct xfs_dir3_free, hdr.hdr.crc)
> -
> -/*
> - * In core version of the free block header, abstracted away from on-disk format
> - * differences. Use this in the code, and convert to/from the disk version using
> - * xfs_dir3_free_hdr_from_disk/xfs_dir3_free_hdr_to_disk.
> - */
> -struct xfs_dir3_icfree_hdr {
> -	__uint32_t	magic;
> -	__uint32_t	firstdb;
> -	__uint32_t	nvalid;
> -	__uint32_t	nused;
> -
> -};
> -
> -void xfs_dir3_free_hdr_from_disk(struct xfs_dir3_icfree_hdr *to,
> -				 struct xfs_dir2_free *from);
> -
> -static inline int
> -xfs_dir3_free_hdr_size(struct xfs_mount *mp)
> -{
> -	if (xfs_sb_version_hascrc(&mp->m_sb))
> -		return sizeof(struct xfs_dir3_free_hdr);
> -	return sizeof(struct xfs_dir2_free_hdr);
> -}
> -
> -static inline int
> -xfs_dir3_free_max_bests(struct xfs_mount *mp)
> -{
> -	return (mp->m_dirblksize - xfs_dir3_free_hdr_size(mp)) /
> -		sizeof(xfs_dir2_data_off_t);
> -}
> -
> -static inline __be16 *
> -xfs_dir3_free_bests_p(struct xfs_mount *mp, struct xfs_dir2_free *free)
> -{
> -	return (__be16 *)((char *)free + xfs_dir3_free_hdr_size(mp));
> -}
> -
> -/*
> - * Convert data space db to the corresponding free db.
> - */
> -static inline xfs_dir2_db_t
> -xfs_dir2_db_to_fdb(struct xfs_mount *mp, xfs_dir2_db_t db)
> -{
> -	return XFS_DIR2_FREE_FIRSTDB(mp) + db / xfs_dir3_free_max_bests(mp);
> -}
> -
> -/*
> - * Convert data space db to the corresponding index in a free db.
> - */
> -static inline int
> -xfs_dir2_db_to_fdindex(struct xfs_mount *mp, xfs_dir2_db_t db)
> -{
> -	return db % xfs_dir3_free_max_bests(mp);
> -}
> -
> -/*
> - * Single block format.
> - *
> - * The single block format looks like the following drawing on disk:
> - *
> - *    +-------------------------------------------------+
> - *    | xfs_dir2_data_hdr_t                             |
> - *    +-------------------------------------------------+
> - *    | xfs_dir2_data_entry_t OR xfs_dir2_data_unused_t |
> - *    | xfs_dir2_data_entry_t OR xfs_dir2_data_unused_t |
> - *    | xfs_dir2_data_entry_t OR xfs_dir2_data_unused_t :
> - *    | ...                                             |
> - *    +-------------------------------------------------+
> - *    | unused space                                    |
> - *    +-------------------------------------------------+
> - *    | ...                                             |
> - *    | xfs_dir2_leaf_entry_t                           |
> - *    | xfs_dir2_leaf_entry_t                           |
> - *    +-------------------------------------------------+
> - *    | xfs_dir2_block_tail_t                           |
> - *    +-------------------------------------------------+
> - *
> - * As all the entries are variable size structures the accessors below should
> - * be used to iterate over them.
> - */
> -
> -typedef struct xfs_dir2_block_tail {
> -	__be32		count;			/* count of leaf entries */
> -	__be32		stale;			/* count of stale lf entries */
> -} xfs_dir2_block_tail_t;
> -
> -/*
> - * Pointer to the leaf header embedded in a data block (1-block format)
> - */
> -static inline struct xfs_dir2_block_tail *
> -xfs_dir2_block_tail_p(struct xfs_mount *mp, struct xfs_dir2_data_hdr *hdr)
> -{
> -	return ((struct xfs_dir2_block_tail *)
> -		((char *)hdr + mp->m_dirblksize)) - 1;
> -}
> -
> -/*
> - * Pointer to the leaf entries embedded in a data block (1-block format)
> - */
> -static inline struct xfs_dir2_leaf_entry *
> -xfs_dir2_block_leaf_p(struct xfs_dir2_block_tail *btp)
> -{
> -	return ((struct xfs_dir2_leaf_entry *)btp) - be32_to_cpu(btp->count);
> -}
> -
> -#endif /* __XFS_DIR2_FORMAT_H__ */
> 

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