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Diffstat (limited to 'fs/xfs/xfs_da_btree.h')
| -rw-r--r-- | fs/xfs/xfs_da_btree.h | 335 |
1 files changed, 335 insertions, 0 deletions
diff --git a/fs/xfs/xfs_da_btree.h b/fs/xfs/xfs_da_btree.h new file mode 100644 index 00000000000..9fc699d9699 --- /dev/null +++ b/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__ */ |