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/*
* Copyright (c) 2000 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_NODE_ENTSIZE_BYNAME /* space a name uses */ \
(sizeof(xfs_da_node_entry_t))
#if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_DA_NODE_ENTRIES)
int xfs_da_node_entries(struct xfs_mount *mp);
#define XFS_DA_NODE_ENTRIES(mp) xfs_da_node_entries(mp)
#else
#define XFS_DA_NODE_ENTRIES(mp) ((mp)->m_da_node_ents)
#endif
#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 */
int rename; /* T/F: this is an atomic rename op */
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 */
int justcheck; /* check for ok with no space */
int addname; /* T/F: this is an add operation */
int 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 */
dev_t dev; /* 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 */
int blocksize; /* logical block size */
int inleaf; /* insert into 1->lf, 0->splf */
xfs_da_state_path_t path; /* search/split paths */
xfs_da_state_path_t altpath; /* alternate path for join */
int extravalid; /* T/F: extrablk is in use */
int 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)
/*========================================================================
* 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 xfs_zone *xfs_da_state_zone;
#endif /* __XFS_DA_BTREE_H__ */
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