/* $NetBSD: namei.h,v 1.120 2024/07/01 00:58:43 christos Exp $ */ /* * WARNING: GENERATED FILE. DO NOT EDIT * (edit namei.src and run make namei in src/sys/sys) * by: NetBSD: gennameih.awk,v 1.5 2009/12/23 14:17:19 pooka Exp * from: NetBSD: namei.src,v 1.65 2024/07/01 00:58:05 christos 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 <sys/queue.h> #include <sys/mutex.h> #if defined(_KERNEL) || defined(_MODULE) #include <sys/kauth.h> #include <sys/rwlock.h> /* * Abstraction for a single pathname. * * This contains both the pathname string and (eventually) all * metadata that determines how the path is to be interpreted. * It is an opaque structure; the implementation is in vfs_lookup.c. * * To call namei, first set up a pathbuf with pathbuf_create or * pathbuf_copyin, then do NDINIT(), then call namei, then AFTER THE * STRUCT NAMEIDATA IS DEAD, call pathbuf_destroy. Don't destroy the * pathbuf before you've finished using the nameidata, or mysterious * bad things may happen. * * pathbuf_assimilate is like pathbuf_create but assumes ownership of * the string buffer passed in, which MUST BE of size PATH_MAX and * have been allocated with PNBUF_GET(). This should only be used when * absolutely necessary; e.g. nfsd uses it for loading paths from * mbufs. */ struct pathbuf; struct pathbuf *pathbuf_create(const char *path); struct pathbuf *pathbuf_assimilate(char *path); int pathbuf_copyin(const char *userpath, struct pathbuf **ret); void pathbuf_destroy(struct pathbuf *); /* get a copy of the (current) path string */ void pathbuf_copystring(const struct pathbuf *, char *buf, size_t maxlen); /* hold a reference copy of the original path string */ const char *pathbuf_stringcopy_get(struct pathbuf *); void pathbuf_stringcopy_put(struct pathbuf *, const char *); // XXX remove this int pathbuf_maybe_copyin(const char *userpath, enum uio_seg seg, struct pathbuf **ret); /* * 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. */ const char *cn_nameptr; /* pointer to looked up name */ size_t cn_namelen; /* length of looked up comp */ }; /* * Encapsulation of namei parameters. */ struct nameidata { /* * Arguments to namei/lookup. */ struct vnode *ni_atdir; /* startup dir, cwd if null */ struct pathbuf *ni_pathbuf; /* pathname container */ char *ni_pnbuf; /* extra pathname buffer ref (XXX) */ /* * Arguments to lookup. */ 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 ni_cnd; }; /* * namei operations */ #define LOOKUP 0 /* perform name lookup only */ #define CREATE 1 /* setup for file creation */ #define DELETE 2 /* setup for file deletion */ #define RENAME 3 /* setup for file renaming */ #define OPMASK 3 /* mask for operation */ /* * namei operational modifier flags, stored in ni_cnd.cn_flags */ #define LOCKLEAF 0x00000004 /* lock inode on return */ #define LOCKPARENT 0x00000008 /* want parent vnode returned locked */ #define TRYEMULROOT 0x00000010 /* try relative to emulation root first */ #define NOCACHE 0x00000020 /* name must not be left in cache */ #define FOLLOW 0x00000040 /* follow symbolic links */ #define NOFOLLOW 0x00000000 /* do not follow symbolic links (pseudo) */ #define EMULROOTSET 0x00000080 /* emulation root already in ni_erootdir */ #define LOCKSHARED 0x00000100 /* want shared locks if possible */ #define NOCHROOT 0x01000000 /* no chroot on abs path lookups */ #define NONEXCLHACK 0x02000000 /* open wwith O_CREAT but not O_EXCL */ #define MODMASK 0x030001fc /* mask of operational modifiers */ /* * Namei parameter descriptors. */ #define NOCROSSMOUNT 0x0000800 /* do not cross mount points */ #define RDONLY 0x0001000 /* lookup with read-only semantics */ #define ISDOTDOT 0x0002000 /* current component name is .. */ #define MAKEENTRY 0x0004000 /* entry is to be added to name cache */ #define ISLASTCN 0x0008000 /* this is last component of pathname */ #define WILLBEDIR 0x0010000 /* new files will be dirs */ #define ISWHITEOUT 0x0020000 /* found whiteout */ #define DOWHITEOUT 0x0040000 /* do whiteouts */ #define REQUIREDIR 0x0080000 /* must be a directory */ #define CREATEDIR 0x0200000 /* trailing slashes are ok */ #define PARAMASK 0x02ff800 /* mask of parameter descriptors */ /* * Initialization of a nameidata structure. */ #define NDINIT(ndp, op, flags, pathbuf) { \ (ndp)->ni_cnd.cn_nameiop = op; \ (ndp)->ni_cnd.cn_flags = flags; \ (ndp)->ni_atdir = NULL; \ (ndp)->ni_pathbuf = pathbuf; \ (ndp)->ni_cnd.cn_cred = kauth_cred_get(); \ } /* * Use this to set the start directory for openat()-type operations. */ #define NDAT(ndp, dir) { \ (ndp)->ni_atdir = (dir); \ } #endif #ifdef __NAMECACHE_PRIVATE #include <sys/rbtree.h> /* * For simplicity (and economy of storage), names longer than * a maximum length of NCHNAMLEN are stored in non-pooled storage. */ #define NCHNAMLEN sizeof(((struct namecache *)NULL)->nc_name) /* * The uintptr_t-sized key value computed for each name consists of name * length and a hash value. On 32-bit platforms the top NC_NLEN_BITS of * the 32-bit hash value is lobbed off. */ #define NC_NLEN_BITS 11 #define NC_NLEN_MASK ((1 << NC_NLEN_BITS) - 1) #define NC_NLEN(ncp) ((ncp)->nc_key & NC_NLEN_MASK) /* * Namecache entry. * * This structure describes the elements in the cache of recent names looked * up by namei. It's carefully sized to take up 128 bytes on _LP64 and 64 * bytes on 32-bit machines, to make good use of space and the CPU caches. * * Items used during RB tree lookup (nc_tree, nc_key) are clustered at the * start of the structure to minimise cache misses during lookup. * * Field markings and their corresponding locks: * * - stable throughout the lifetime of the namecache entry * d protected by nc_dvp->vi_nc_lock * v protected by nc_vp->vi_nc_listlock * l protected by cache_lru_lock */ struct namecache { struct rb_node nc_tree; /* d red-black tree, must be first */ uintptr_t nc_key; /* - hashed key value */ TAILQ_ENTRY(namecache) nc_list; /* v nc_vp's list of cache entries */ TAILQ_ENTRY(namecache) nc_lru; /* l pseudo-lru chain */ struct vnode *nc_dvp; /* - vnode of parent of name */ struct vnode *nc_vp; /* - vnode the name refers to */ u_char nc_lrulist; /* l LRU list entry is on */ u_char nc_whiteout; /* - whiteout indicator */ #ifdef _LP64 char nc_name[46]; /* - segment name */ #else char nc_name[22]; /* - segment name */ #endif }; #endif /* __NAMECACHE_PRIVATE */ #ifdef _KERNEL #include <sys/kmem.h> struct mount; struct cpu_info; #define PNBUF_GET() ((char *)kmem_alloc(MAXPATHLEN, KM_SLEEP)) #define PNBUF_PUT(pnb) kmem_free((pnb), MAXPATHLEN) /* * Typesafe flags for namei_simple/nameiat_simple. * * This encoding is not optimal but serves the important purpose of * not being type-compatible with the regular namei flags. */ struct namei_simple_flags_type; /* Opaque. */ typedef const struct namei_simple_flags_type *namei_simple_flags_t; /* Gross. */ extern const namei_simple_flags_t NSM_NOFOLLOW_NOEMULROOT, NSM_NOFOLLOW_TRYEMULROOT, NSM_FOLLOW_NOEMULROOT, NSM_FOLLOW_TRYEMULROOT; /* * namei(at)?_simple_* - the simple cases of namei, with no struct * nameidata involved. * * namei_simple_kernel takes a kernel-space path as the first argument. * namei_simple_user takes a user-space path as the first argument. * The nameiat_simple* variants handle relative path using the given * directory vnode instead of current directory. * * A namei call can be converted to namei_simple_* if: * - the second arg to NDINIT is LOOKUP; * - it does not need the parent vnode, nd.ni_dvp; * - the only flags it uses are (NO)FOLLOW and TRYEMULROOT; * - it does not do anything else gross with the contents of nd. */ int namei_simple_kernel(const char *, namei_simple_flags_t, struct vnode **); int namei_simple_user(const char *, namei_simple_flags_t, struct vnode **); int nameiat_simple(struct vnode *, struct pathbuf *, namei_simple_flags_t, struct vnode **); int nameiat_simple_kernel(struct vnode *, const char *, namei_simple_flags_t, struct vnode **); int nameiat_simple_user(struct vnode *, const char *, namei_simple_flags_t, struct vnode **); int namei(struct nameidata *); uint32_t namei_hash(const char *, const char **); int lookup_for_nfsd(struct nameidata *, struct vnode *, int neverfollow); int lookup_for_nfsd_index(struct nameidata *, struct vnode *); int relookup(struct vnode *, struct vnode **, struct componentname *, int); void cache_purge1(struct vnode *, const char *, size_t, int); #define PURGE_PARENTS 1 #define PURGE_CHILDREN 2 #define cache_purge(vp) cache_purge1((vp),NULL,0,PURGE_PARENTS|PURGE_CHILDREN) bool cache_lookup(struct vnode *, const char *, size_t, uint32_t, uint32_t, int *, struct vnode **); bool cache_lookup_raw(struct vnode *, const char *, size_t, uint32_t, int *, struct vnode **); bool cache_lookup_linked(struct vnode *, const char *, size_t, struct vnode **, krwlock_t **, kauth_cred_t); int cache_revlookup(struct vnode *, struct vnode **, char **, char *, bool, accmode_t); int cache_diraccess(struct vnode *, int); void cache_enter(struct vnode *, struct vnode *, const char *, size_t, uint32_t); void cache_enter_id(struct vnode *, mode_t, uid_t, gid_t, bool); bool cache_have_id(struct vnode *); void cache_vnode_init(struct vnode * ); void cache_vnode_fini(struct vnode * ); void cache_cpu_init(struct cpu_info *); void cache_enter_mount(struct vnode *, struct vnode *); bool cache_cross_mount(struct vnode **, krwlock_t **); bool cache_lookup_mount(struct vnode *, struct vnode **); void nchinit(void); void namecache_count_pass2(void); void namecache_count_2passes(void); void cache_purgevfs(struct mount *); void namecache_print(struct vnode *, void (*)(const char *, ...) __printflike(1, 2)); #endif /* * Stats on usefulness of namei caches. A couple of structures are * used for counting, with members having the same names but different * types. Containerize member names with the preprocessor to avoid * cut-'n'-paste. */ #define _NAMEI_CACHE_STATS(type) { \ type ncs_goodhits; /* hits that we can really use */ \ type ncs_neghits; /* negative hits that we can use */ \ type ncs_badhits; /* hits we must drop */ \ type ncs_falsehits; /* hits with id mismatch */ \ type ncs_miss; /* misses */ \ type ncs_long; /* long names that ignore cache */ \ type ncs_pass2; /* names found with passes == 2 */ \ type ncs_2passes; /* number of times we attempt it */ \ type ncs_revhits; /* reverse-cache hits */ \ type ncs_revmiss; /* reverse-cache misses */ \ type ncs_denied; /* access denied */ \ } /* * Sysctl deals with a uint64_t version of the stats and summary * totals are kept that way. */ struct nchstats _NAMEI_CACHE_STATS(uint64_t); /* #endif !_SYS_NAMEI_H_ (generated by gennameih.awk) */ /* Definitions match above, but with NAMEI_ prefix */ #define NAMEI_LOOKUP 0 #define NAMEI_CREATE 1 #define NAMEI_DELETE 2 #define NAMEI_RENAME 3 #define NAMEI_OPMASK 3 #define NAMEI_LOCKLEAF 0x00000004 #define NAMEI_LOCKPARENT 0x00000008 #define NAMEI_TRYEMULROOT 0x00000010 #define NAMEI_NOCACHE 0x00000020 #define NAMEI_FOLLOW 0x00000040 #define NAMEI_NOFOLLOW 0x00000000 #define NAMEI_EMULROOTSET 0x00000080 #define NAMEI_LOCKSHARED 0x00000100 #define NAMEI_NOCHROOT 0x01000000 #define NAMEI_NONEXCLHACK 0x02000000 #define NAMEI_MODMASK 0x030001fc #define NAMEI_NOCROSSMOUNT 0x0000800 #define NAMEI_RDONLY 0x0001000 #define NAMEI_ISDOTDOT 0x0002000 #define NAMEI_MAKEENTRY 0x0004000 #define NAMEI_ISLASTCN 0x0008000 #define NAMEI_WILLBEDIR 0x0010000 #define NAMEI_ISWHITEOUT 0x0020000 #define NAMEI_DOWHITEOUT 0x0040000 #define NAMEI_REQUIREDIR 0x0080000 #define NAMEI_CREATEDIR 0x0200000 #define NAMEI_PARAMASK 0x02ff800 #endif /* !_SYS_NAMEI_H_ */
