/* $NetBSD: namei.src,v 1.8.4.1 2009/05/04 08:14:35 yamt Exp $ */ /* * Copyright (c) 1985, 1989, 1991, 1993 * The Regents of the University of California. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * @(#)namei.h 8.5 (Berkeley) 8/20/94 */ #ifndef _SYS_NAMEI_H_ #define _SYS_NAMEI_H_ #include #include #ifdef _KERNEL #include /* * Encapsulation of namei parameters. */ struct nameidata { /* * Arguments to namei/lookup. */ const char *ni_dirp; /* pathname pointer */ enum uio_seg ni_segflg; /* location of pathname */ /* * Arguments to lookup. */ struct vnode *ni_startdir; /* starting directory */ struct vnode *ni_rootdir; /* logical root directory */ struct vnode *ni_erootdir; /* emulation root directory */ /* * Results: returned from/manipulated by lookup */ struct vnode *ni_vp; /* vnode of result */ struct vnode *ni_dvp; /* vnode of intermediate directory */ /* * Shared between namei and lookup/commit routines. */ size_t ni_pathlen; /* remaining chars in path */ const char *ni_next; /* next location in pathname */ unsigned int ni_loopcnt; /* count of symlinks encountered */ /* * Lookup parameters: this structure describes the subset of * information from the nameidata structure that is passed * through the VOP interface. */ struct componentname { /* * Arguments to lookup. */ uint32_t cn_nameiop; /* namei operation */ uint32_t cn_flags; /* flags to namei */ kauth_cred_t cn_cred; /* credentials */ /* * Shared between lookup and commit routines. */ char *cn_pnbuf; /* pathname buffer */ const char *cn_nameptr; /* pointer to looked up name */ size_t cn_namelen; /* length of looked up comp */ u_long cn_hash; /* hash val of looked up name */ size_t cn_consume; /* chars to consume in lookup */ } ni_cnd; }; /* * namei operations */ NAMEIFL LOOKUP 0 /* perform name lookup only */ NAMEIFL CREATE 1 /* setup for file creation */ NAMEIFL DELETE 2 /* setup for file deletion */ NAMEIFL RENAME 3 /* setup for file renaming */ NAMEIFL OPMASK 3 /* mask for operation */ /* * namei operational modifier flags, stored in ni_cnd.cn_flags */ NAMEIFL LOCKLEAF 0x00000004 /* lock inode on return */ NAMEIFL LOCKPARENT 0x00000008 /* want parent vnode returned locked */ NAMEIFL TRYEMULROOT 0x00000010 /* try relative to emulation root first */ NAMEIFL NOCACHE 0x00000020 /* name must not be left in cache */ NAMEIFL FOLLOW 0x00000040 /* follow symbolic links */ NAMEIFL NOFOLLOW 0x00000000 /* do not follow symbolic links (pseudo) */ NAMEIFL EMULROOTSET 0x00000080 /* emulation root already in ni_erootdir */ NAMEIFL NOCHROOT 0x01000000 /* no chroot on abs path lookups */ NAMEIFL MODMASK 0x010000fc /* mask of operational modifiers */ /* * Namei parameter descriptors. * * SAVENAME may be set by either the callers of namei or by VOP_LOOKUP. * If the caller of namei sets the flag (for example execve wants to * know the name of the program that is being executed), then it must * free the buffer. If VOP_LOOKUP sets the flag, then the buffer must * be freed by either the commit routine or the VOP_ABORT routine. * SAVESTART is set only by the callers of namei. It implies SAVENAME * plus the addition of saving the parent directory that contains the * name in ni_startdir. It allows repeated calls to lookup for the * name being sought. The caller is responsible for releasing the * buffer and for vrele'ing ni_startdir. */ NAMEIFL NOCROSSMOUNT 0x0000100 /* do not cross mount points */ NAMEIFL RDONLY 0x0000200 /* lookup with read-only semantics */ NAMEIFL HASBUF 0x0000400 /* has allocated pathname buffer */ NAMEIFL SAVENAME 0x0000800 /* save pathname buffer */ NAMEIFL SAVESTART 0x0001000 /* save starting directory */ NAMEIFL ISDOTDOT 0x0002000 /* current component name is .. */ NAMEIFL MAKEENTRY 0x0004000 /* entry is to be added to name cache */ NAMEIFL ISLASTCN 0x0008000 /* this is last component of pathname */ NAMEIFL ISSYMLINK 0x0010000 /* symlink needs interpretation */ NAMEIFL ISWHITEOUT 0x0020000 /* found whiteout */ NAMEIFL DOWHITEOUT 0x0040000 /* do whiteouts */ NAMEIFL REQUIREDIR 0x0080000 /* must be a directory */ NAMEIFL CREATEDIR 0x0200000 /* trailing slashes are ok */ NAMEIFL PARAMASK 0x02fff00 /* mask of parameter descriptors */ /* * Initialization of an nameidata structure. */ #define NDINIT(ndp, op, flags, segflg, namep) { \ (ndp)->ni_cnd.cn_nameiop = op; \ (ndp)->ni_cnd.cn_flags = flags; \ (ndp)->ni_segflg = segflg; \ (ndp)->ni_dirp = namep; \ (ndp)->ni_cnd.cn_cred = kauth_cred_get(); \ } #endif /* * This structure describes the elements in the cache of recent * names looked up by namei. NCHNAMLEN is sized to make structure * size a power of two to optimize malloc's. Minimum reasonable * size is 15. */ #define NCHNAMLEN 31 /* maximum name segment length we bother with */ /* * Namecache entry. This structure is arranged so that frequently * accessed and mostly read-only data is toward the front, with * infrequently accessed data and the lock towards the rear. The * lock is then more likely to be in a seperate cache line. */ struct namecache { LIST_ENTRY(namecache) nc_hash; /* hash chain */ LIST_ENTRY(namecache) nc_vhash; /* directory hash chain */ struct vnode *nc_dvp; /* vnode of parent of name */ struct vnode *nc_vp; /* vnode the name refers to */ int nc_flags; /* copy of componentname's ISWHITEOUT */ char nc_nlen; /* length of name */ char nc_name[NCHNAMLEN]; /* segment name */ void *nc_gcqueue; /* queue for garbage collection */ TAILQ_ENTRY(namecache) nc_lru; /* psuedo-lru chain */ LIST_ENTRY(namecache) nc_dvlist; LIST_ENTRY(namecache) nc_vlist; kmutex_t nc_lock; /* lock on this entry */ int nc_hittime; /* last time scored a hit */ }; #ifdef _KERNEL #include #include struct mount; struct cpu_info; extern pool_cache_t pnbuf_cache; /* pathname buffer cache */ #define PNBUF_GET() pool_cache_get(pnbuf_cache, PR_WAITOK) #define PNBUF_PUT(pnb) pool_cache_put(pnbuf_cache, (pnb)) int namei(struct nameidata *); uint32_t namei_hash(const char *, const char **); int lookup(struct nameidata *); int relookup(struct vnode *, struct vnode **, struct componentname *); void cache_purge1(struct vnode *, const struct componentname *, int); #define PURGE_PARENTS 1 #define PURGE_CHILDREN 2 #define cache_purge(vp) cache_purge1((vp), NULL, PURGE_PARENTS|PURGE_CHILDREN) int cache_lookup(struct vnode *, struct vnode **, struct componentname *); int cache_lookup_raw(struct vnode *, struct vnode **, struct componentname *); int cache_revlookup(struct vnode *, struct vnode **, char **, char *); void cache_enter(struct vnode *, struct vnode *, struct componentname *); void nchinit(void); void nchreinit(void); void cache_cpu_init(struct cpu_info *); void cache_purgevfs(struct mount *); void namecache_print(struct vnode *, void (*)(const char *, ...)); #endif /* * Stats on usefulness of namei caches. * XXX: should be 64-bit counters. */ struct nchstats { long ncs_goodhits; /* hits that we can really use */ long ncs_neghits; /* negative hits that we can use */ long ncs_badhits; /* hits we must drop */ long ncs_falsehits; /* hits with id mismatch */ long ncs_miss; /* misses */ long ncs_long; /* long names that ignore cache */ long ncs_pass2; /* names found with passes == 2 */ long ncs_2passes; /* number of times we attempt it */ long ncs_revhits; /* reverse-cache hits */ long ncs_revmiss; /* reverse-cache misses */ }; #ifdef _KERNEL extern struct nchstats nchstats; #endif /* #endif !_SYS_NAMEI_H_ (generated by gennameih.awk) */