patch-2.4.25 linux-2.4.25/fs/xfs/xfs_da_btree.h

• Lines: 336
• Date: 2004-02-18 05:36:32.000000000 -0800
• Orig file: linux-2.4.24/fs/xfs/xfs_da_btree.h
• Orig date: 1969-12-31 16:00:00.000000000 -0800

diff -urN linux-2.4.24/fs/xfs/xfs_da_btree.h linux-2.4.25/fs/xfs/xfs_da_btree.h
@@ -0,0 +1,335 @@
+/*
+ * 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__ */