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diff --git a/fs/xfs/xfs_da_btree.h b/fs/xfs/xfs_da_btree.h
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+++ b/fs/xfs/xfs_da_btree.h
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+/*
+ * Copyright (c) 2000, 2002 Silicon Graphics, Inc.  All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of version 2 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.
+ *
+ * Further, this software is distributed without any warranty that it is
+ * free of the rightful claim of any third person regarding infringement
+ * or the like.  Any license provided herein, whether implied or
+ * otherwise, applies only to this software file.  Patent licenses, if
+ * any, provided herein do not apply to combinations of this program with
+ * other software, or any other product whatsoever.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write the Free Software Foundation, Inc., 59
+ * Temple Place - Suite 330, Boston MA 02111-1307, USA.
+ *
+ * Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
+ * Mountain View, CA  94043, or:
+ *
+ * http://www.sgi.com
+ *
+ * For further information regarding this notice, see:
+ *
+ * http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/
+ */
+#ifndef __XFS_DA_BTREE_H__
+#define __XFS_DA_BTREE_H__
+
+struct xfs_buf;
+struct xfs_bmap_free;
+struct xfs_inode;
+struct xfs_mount;
+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.
+ *
+ * Is 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_DIR_LEAF_MAGIC      0xfeeb  /* magic number: directory leaf blks */
+#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 */
+
+#define XFS_DIRX_LEAF_MAGIC(mp) \
+        (XFS_DIR_IS_V1(mp) ? XFS_DIR_LEAF_MAGIC : XFS_DIR2_LEAFN_MAGIC)
+
+typedef struct xfs_da_blkinfo {
+        xfs_dablk_t forw;                       /* previous block in list */
+        xfs_dablk_t back;                       /* following block in list */
+        __uint16_t magic;                       /* validity check on block */
+        __uint16_t pad;                         /* unused */
+} xfs_da_blkinfo_t;
+
+/*
+ * 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_intnode {
+        struct xfs_da_node_hdr {        /* constant-structure header block */
+                xfs_da_blkinfo_t info;  /* block type, links, etc. */
+                __uint16_t count;       /* count of active entries */
+                __uint16_t level;       /* level above leaves (leaf == 0) */
+        } hdr;
+        struct xfs_da_node_entry {
+                xfs_dahash_t hashval;   /* hash value for this descendant */
+                xfs_dablk_t before;     /* Btree block before this key */
+        } btree[1];                     /* variable sized array of keys */
+} xfs_da_intnode_t;
+typedef struct xfs_da_node_hdr xfs_da_node_hdr_t;
+typedef struct xfs_da_node_entry xfs_da_node_entry_t;
+
+#define XFS_DA_MAXHASH  ((xfs_dahash_t)-1) /* largest valid hash value */
+
+/*
+ * Macros used by directory code to interface to the filesystem.
+ */
+#if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_LBSIZE)
+int xfs_lbsize(struct xfs_mount *mp);
+#define XFS_LBSIZE(mp)                  xfs_lbsize(mp)
+#else
+#define XFS_LBSIZE(mp)  ((mp)->m_sb.sb_blocksize)
+#endif
+#if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_LBLOG)
+int xfs_lblog(struct xfs_mount *mp);
+#define XFS_LBLOG(mp)                   xfs_lblog(mp)
+#else
+#define XFS_LBLOG(mp)   ((mp)->m_sb.sb_blocklog)
+#endif
+
+/*
+ * Macros used by directory code to interface to the kernel
+ */
+
+/*
+ * Macros used to manipulate directory off_t's
+ */
+#if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_DA_MAKE_BNOENTRY)
+__uint32_t xfs_da_make_bnoentry(struct xfs_mount *mp, xfs_dablk_t bno,
+                                int entry);
+#define XFS_DA_MAKE_BNOENTRY(mp,bno,entry)      \
+        xfs_da_make_bnoentry(mp,bno,entry)
+#else
+#define XFS_DA_MAKE_BNOENTRY(mp,bno,entry) \
+        (((bno) << (mp)->m_dircook_elog) | (entry))
+#endif
+#if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_DA_MAKE_COOKIE)
+xfs_off_t xfs_da_make_cookie(struct xfs_mount *mp, xfs_dablk_t bno, int entry,
+                                xfs_dahash_t hash);
+#define XFS_DA_MAKE_COOKIE(mp,bno,entry,hash)   \
+        xfs_da_make_cookie(mp,bno,entry,hash)
+#else
+#define XFS_DA_MAKE_COOKIE(mp,bno,entry,hash) \
+        (((xfs_off_t)XFS_DA_MAKE_BNOENTRY(mp, bno, entry) << 32) | (hash))
+#endif
+#if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_DA_COOKIE_HASH)
+xfs_dahash_t xfs_da_cookie_hash(struct xfs_mount *mp, xfs_off_t cookie);
+#define XFS_DA_COOKIE_HASH(mp,cookie)           xfs_da_cookie_hash(mp,cookie)
+#else
+#define XFS_DA_COOKIE_HASH(mp,cookie)   ((xfs_dahash_t)(cookie))
+#endif
+#if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_DA_COOKIE_BNO)
+xfs_dablk_t xfs_da_cookie_bno(struct xfs_mount *mp, xfs_off_t cookie);
+#define XFS_DA_COOKIE_BNO(mp,cookie)            xfs_da_cookie_bno(mp,cookie)
+#else
+#define XFS_DA_COOKIE_BNO(mp,cookie) \
+        (((xfs_off_t)(cookie) >> 31) == -1LL ? \
+                (xfs_dablk_t)0 : \
+                (xfs_dablk_t)((xfs_off_t)(cookie) >> ((mp)->m_dircook_elog + 32)))
+#endif
+#if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_DA_COOKIE_ENTRY)
+int xfs_da_cookie_entry(struct xfs_mount *mp, xfs_off_t cookie);
+#define XFS_DA_COOKIE_ENTRY(mp,cookie)          xfs_da_cookie_entry(mp,cookie)
+#else
+#define XFS_DA_COOKIE_ENTRY(mp,cookie) \
+        (((xfs_off_t)(cookie) >> 31) == -1LL ? \
+                (xfs_dablk_t)0 : \
+                (xfs_dablk_t)(((xfs_off_t)(cookie) >> 32) & \
+                              ((1 << (mp)->m_dircook_elog) - 1)))
+#endif
+
+
+/*========================================================================
+ * Btree searching and modification structure definitions.
+ *========================================================================*/
+
+/*
+ * Structure to ease passing around component names.
+ */
+typedef struct xfs_da_args {
+        uchar_t         *name;          /* string (maybe not NULL terminated) */
+        int             namelen;        /* length of string (maybe no NULL) */
+        uchar_t         *value;         /* set of bytes (maybe contain NULLs) */
+        int             valuelen;       /* length of value */
+        int             flags;          /* argument flags (eg: ATTR_NOCREATE) */
+        xfs_dahash_t    hashval;        /* hash value of name */
+        xfs_ino_t       inumber;        /* input/output inode number */
+        struct xfs_inode *dp;           /* directory inode to manipulate */
+        xfs_fsblock_t   *firstblock;    /* ptr to firstblock for bmap calls */
+        struct xfs_bmap_free *flist;    /* ptr to freelist for bmap_finish */
+        struct xfs_trans *trans;        /* current trans (changes over time) */
+        xfs_extlen_t    total;          /* total blocks needed, for 1st bmap */
+        int             whichfork;      /* data or attribute fork */
+        xfs_dablk_t     blkno;          /* blkno of attr leaf of interest */
+        int             index;          /* index of attr of interest in blk */
+        xfs_dablk_t     rmtblkno;       /* remote attr value starting blkno */
+        int             rmtblkcnt;      /* remote attr value block count */
+        xfs_dablk_t     blkno2;         /* blkno of 2nd attr leaf of interest */
+        int             index2;         /* index of 2nd attr in blk */
+        xfs_dablk_t     rmtblkno2;      /* remote attr value starting blkno */
+        int             rmtblkcnt2;     /* remote attr value block count */
+        unsigned char   justcheck;      /* T/F: check for ok with no space */
+        unsigned char   rename;         /* T/F: this is an atomic rename op */
+        unsigned char   addname;        /* T/F: this is an add operation */
+        unsigned char   oknoent;        /* T/F: ok to return ENOENT, else die */
+} xfs_da_args_t;
+
+/*
+ * Structure to describe buffer(s) for a block.
+ * This is needed in the directory version 2 format case, when
+ * multiple non-contiguous fsblocks might be needed to cover one
+ * logical directory block.
+ * If the buffer count is 1 then the data pointer points to the
+ * same place as the b_addr field for the buffer, else to kmem_alloced memory.
+ */
+typedef struct xfs_dabuf {
+        int             nbuf;           /* number of buffer pointers present */
+        short           dirty;          /* data needs to be copied back */
+        short           bbcount;        /* how large is data in bbs */
+        void            *data;          /* pointer for buffers' data */
+#ifdef XFS_DABUF_DEBUG
+        inst_t          *ra;            /* return address of caller to make */
+        struct xfs_dabuf *next;         /* next in global chain */
+        struct xfs_dabuf *prev;         /* previous in global chain */
+        struct xfs_buftarg *target;     /* device for buffer */
+        xfs_daddr_t     blkno;          /* daddr first in bps[0] */
+#endif
+        struct xfs_buf  *bps[1];        /* actually nbuf of these */
+} xfs_dabuf_t;
+#define XFS_DA_BUF_SIZE(n)      \
+        (sizeof(xfs_dabuf_t) + sizeof(struct xfs_buf *) * ((n) - 1))
+
+#ifdef XFS_DABUF_DEBUG
+extern xfs_dabuf_t      *xfs_dabuf_global_list;
+#endif
+
+/*
+ * Storage for holding state during Btree searches and split/join ops.
+ *
+ * Only need space for 5 intermediate nodes.  With a minimum of 62-way
+ * fanout to the Btree, we can support over 900 million directory blocks,
+ * which is slightly more than enough.
+ */
+typedef struct xfs_da_state_blk {
+        xfs_dabuf_t     *bp;            /* buffer containing block */
+        xfs_dablk_t     blkno;          /* filesystem blkno of buffer */
+        xfs_daddr_t     disk_blkno;     /* on-disk blkno (in BBs) of buffer */
+        int             index;          /* relevant index into block */
+        xfs_dahash_t    hashval;        /* last hash value in block */
+        int             magic;          /* blk's magic number, ie: blk type */
+} xfs_da_state_blk_t;
+
+typedef struct xfs_da_state_path {
+        int                     active;         /* number of active levels */
+        xfs_da_state_blk_t      blk[XFS_DA_NODE_MAXDEPTH];
+} xfs_da_state_path_t;
+
+typedef struct xfs_da_state {
+        xfs_da_args_t           *args;          /* filename arguments */
+        struct xfs_mount        *mp;            /* filesystem mount point */
+        unsigned int            blocksize;      /* logical block size */
+        unsigned int            node_ents;      /* how many entries in danode */
+        xfs_da_state_path_t     path;           /* search/split paths */
+        xfs_da_state_path_t     altpath;        /* alternate path for join */
+        unsigned char           inleaf;         /* insert into 1->lf, 0->splf */
+        unsigned char           extravalid;     /* T/F: extrablk is in use */
+        unsigned char           extraafter;     /* T/F: extrablk is after new */
+        xfs_da_state_blk_t      extrablk;       /* for double-splits on leafs */
+                                                /* for dirv2 extrablk is data */
+} xfs_da_state_t;
+
+/*
+ * Utility macros to aid in logging changed structure fields.
+ */
+#define XFS_DA_LOGOFF(BASE, ADDR)       ((char *)(ADDR) - (char *)(BASE))
+#define XFS_DA_LOGRANGE(BASE, ADDR, SIZE)       \
+                (uint)(XFS_DA_LOGOFF(BASE, ADDR)), \
+                (uint)(XFS_DA_LOGOFF(BASE, ADDR)+(SIZE)-1)
+
+
+#ifdef __KERNEL__
+/*========================================================================
+ * Function prototypes for the kernel.
+ *========================================================================*/
+
+/*
+ * Routines used for growing the Btree.
+ */
+int     xfs_da_node_create(xfs_da_args_t *args, xfs_dablk_t blkno, int level,
+                                         xfs_dabuf_t **bpp, int whichfork);
+int     xfs_da_split(xfs_da_state_t *state);
+
+/*
+ * Routines used for shrinking the Btree.
+ */
+int     xfs_da_join(xfs_da_state_t *state);
+void    xfs_da_fixhashpath(xfs_da_state_t *state,
+                                          xfs_da_state_path_t *path_to_to_fix);
+
+/*
+ * Routines used for finding things in the Btree.
+ */
+int     xfs_da_node_lookup_int(xfs_da_state_t *state, int *result);
+int     xfs_da_path_shift(xfs_da_state_t *state, xfs_da_state_path_t *path,
+                                         int forward, int release, int *result);
+/*
+ * Utility routines.
+ */
+int     xfs_da_blk_unlink(xfs_da_state_t *state, xfs_da_state_blk_t *drop_blk,
+                                         xfs_da_state_blk_t *save_blk);
+int     xfs_da_blk_link(xfs_da_state_t *state, xfs_da_state_blk_t *old_blk,
+                                       xfs_da_state_blk_t *new_blk);
+
+/*
+ * Utility routines.
+ */
+int     xfs_da_grow_inode(xfs_da_args_t *args, xfs_dablk_t *new_blkno);
+int     xfs_da_get_buf(struct xfs_trans *trans, struct xfs_inode *dp,
+                              xfs_dablk_t bno, xfs_daddr_t mappedbno,
+                              xfs_dabuf_t **bp, int whichfork);
+int     xfs_da_read_buf(struct xfs_trans *trans, struct xfs_inode *dp,
+                               xfs_dablk_t bno, xfs_daddr_t mappedbno,
+                               xfs_dabuf_t **bpp, int whichfork);
+xfs_daddr_t     xfs_da_reada_buf(struct xfs_trans *trans, struct xfs_inode *dp,
+                        xfs_dablk_t bno, int whichfork);
+int     xfs_da_shrink_inode(xfs_da_args_t *args, xfs_dablk_t dead_blkno,
+                                          xfs_dabuf_t *dead_buf);
+
+uint xfs_da_hashname(uchar_t *name_string, int name_length);
+uint xfs_da_log2_roundup(uint i);
+xfs_da_state_t *xfs_da_state_alloc(void);
+void xfs_da_state_free(xfs_da_state_t *state);
+void xfs_da_state_kill_altpath(xfs_da_state_t *state);
+
+void xfs_da_buf_done(xfs_dabuf_t *dabuf);
+void xfs_da_log_buf(struct xfs_trans *tp, xfs_dabuf_t *dabuf, uint first,
+                           uint last);
+void xfs_da_brelse(struct xfs_trans *tp, xfs_dabuf_t *dabuf);
+void xfs_da_binval(struct xfs_trans *tp, xfs_dabuf_t *dabuf);
+xfs_daddr_t xfs_da_blkno(xfs_dabuf_t *dabuf);
+
+extern struct kmem_zone *xfs_da_state_zone;
+#endif  /* __KERNEL__ */
+
+#endif  /* __XFS_DA_BTREE_H__ */