1 /* $NetBSD: namei.h,v 1.70 2010/11/30 10:44:44 dholland Exp $ */ 2 3 4 /* 5 * WARNING: GENERATED FILE. DO NOT EDIT 6 * (edit namei.src and run make namei in src/sys/sys) 7 * by: NetBSD: gennameih.awk,v 1.5 2009/12/23 14:17:19 pooka Exp 8 * from: NetBSD: namei.src,v 1.17 2010/11/30 10:43:01 dholland Exp 9 */ 10 11 /* 12 * Copyright (c) 1985, 1989, 1991, 1993 13 * The Regents of the University of California. All rights reserved. 14 * 15 * Redistribution and use in source and binary forms, with or without 16 * modification, are permitted provided that the following conditions 17 * are met: 18 * 1. Redistributions of source code must retain the above copyright 19 * notice, this list of conditions and the following disclaimer. 20 * 2. Redistributions in binary form must reproduce the above copyright 21 * notice, this list of conditions and the following disclaimer in the 22 * documentation and/or other materials provided with the distribution. 23 * 3. Neither the name of the University nor the names of its contributors 24 * may be used to endorse or promote products derived from this software 25 * without specific prior written permission. 26 * 27 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 28 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 29 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 30 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 31 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 32 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 33 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 34 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 35 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 36 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 37 * SUCH DAMAGE. 38 * 39 * @(#)namei.h 8.5 (Berkeley) 8/20/94 40 */ 41 42 #ifndef _SYS_NAMEI_H_ 43 #define _SYS_NAMEI_H_ 44 45 #include <sys/queue.h> 46 #include <sys/mutex.h> 47 48 #ifdef _KERNEL 49 #include <sys/kauth.h> 50 51 /* 52 * Abstraction for a single pathname. 53 * 54 * This contains both the pathname string and (eventually) all 55 * metadata that determines how the path is to be interpreted. 56 * It is an opaque structure; the implementation is in vfs_lookup.c. 57 * 58 * To call namei, first set up a pathbuf with pathbuf_create or 59 * pathbuf_copyin, then do NDINIT(), then call namei, then AFTER THE 60 * STRUCT NAMEIDATA IS DEAD, call pathbuf_destroy. Don't destroy the 61 * pathbuf before you've finished using the nameidata, or mysterious 62 * bad things may happen. 63 * 64 * pathbuf_assimilate is like pathbuf_create but assumes ownership of 65 * the string buffer passed in, which MUST BE of size PATH_MAX and 66 * have been allocated with PNBUF_GET(). This should only be used when 67 * absolutely necessary; e.g. nfsd uses it for loading paths from 68 * mbufs. 69 */ 70 struct pathbuf; 71 72 struct pathbuf *pathbuf_create(const char *path); 73 struct pathbuf *pathbuf_assimilate(char *path); 74 int pathbuf_copyin(const char *userpath, struct pathbuf **ret); 75 void pathbuf_destroy(struct pathbuf *); 76 77 /* get a copy of the (current) path string */ 78 void pathbuf_copystring(const struct pathbuf *, char *buf, size_t maxlen); 79 80 /* hold a reference copy of the original path string */ 81 const char *pathbuf_stringcopy_get(struct pathbuf *); 82 void pathbuf_stringcopy_put(struct pathbuf *, const char *); 83 84 // XXX remove this 85 int pathbuf_maybe_copyin(const char *userpath, enum uio_seg seg, struct pathbuf **ret); 86 87 /* 88 * Encapsulation of namei parameters. 89 */ 90 struct nameidata { 91 /* 92 * Arguments to namei/lookup. 93 */ 94 struct pathbuf *ni_pathbuf; /* pathname container */ 95 char *ni_pnbuf; /* extra pathname buffer ref (XXX) */ 96 /* 97 * Arguments to lookup. 98 */ 99 struct vnode *ni_startdir; /* starting directory */ 100 struct vnode *ni_rootdir; /* logical root directory */ 101 struct vnode *ni_erootdir; /* emulation root directory */ 102 /* 103 * Results: returned from/manipulated by lookup 104 */ 105 struct vnode *ni_vp; /* vnode of result */ 106 struct vnode *ni_dvp; /* vnode of intermediate directory */ 107 /* 108 * Shared between namei and lookup/commit routines. 109 */ 110 size_t ni_pathlen; /* remaining chars in path */ 111 const char *ni_next; /* next location in pathname */ 112 unsigned int ni_loopcnt; /* count of symlinks encountered */ 113 /* 114 * Lookup parameters: this structure describes the subset of 115 * information from the nameidata structure that is passed 116 * through the VOP interface. 117 */ 118 struct componentname { 119 /* 120 * Arguments to lookup. 121 */ 122 uint32_t cn_nameiop; /* namei operation */ 123 uint32_t cn_flags; /* flags to namei */ 124 kauth_cred_t cn_cred; /* credentials */ 125 /* 126 * Shared between lookup and commit routines. 127 */ 128 const char *cn_nameptr; /* pointer to looked up name */ 129 size_t cn_namelen; /* length of looked up comp */ 130 u_long cn_hash; /* hash val of looked up name */ 131 size_t cn_consume; /* chars to consume in lookup */ 132 } ni_cnd; 133 }; 134 135 /* 136 * namei operations 137 */ 138 #define LOOKUP 0 /* perform name lookup only */ 139 #define CREATE 1 /* setup for file creation */ 140 #define DELETE 2 /* setup for file deletion */ 141 #define RENAME 3 /* setup for file renaming */ 142 #define OPMASK 3 /* mask for operation */ 143 /* 144 * namei operational modifier flags, stored in ni_cnd.cn_flags 145 */ 146 #define LOCKLEAF 0x00000004 /* lock inode on return */ 147 #define LOCKPARENT 0x00000008 /* want parent vnode returned locked */ 148 #define TRYEMULROOT 0x00000010 /* try relative to emulation root 149 first */ 150 #define NOCACHE 0x00000020 /* name must not be left in cache */ 151 #define FOLLOW 0x00000040 /* follow symbolic links */ 152 #define NOFOLLOW 0x00000000 /* do not follow symbolic links 153 (pseudo) */ 154 #define EMULROOTSET 0x00000080 /* emulation root already 155 in ni_erootdir */ 156 #define NOCHROOT 0x01000000 /* no chroot on abs path lookups */ 157 #define MODMASK 0x010000fc /* mask of operational modifiers */ 158 /* 159 * Namei parameter descriptors. 160 * 161 * SAVESTART is set only by the callers of namei. It implies saving 162 * the parent directory that contains the name in ni_startdir. It 163 * allows repeated calls to lookup for the name being sought. The 164 * caller is responsible for vrele'ing ni_startdir. 165 */ 166 #define NOCROSSMOUNT 0x0000100 /* do not cross mount points */ 167 #define RDONLY 0x0000200 /* lookup with read-only semantics */ 168 #define SAVESTART 0x0001000 /* save starting directory */ 169 #define ISDOTDOT 0x0002000 /* current component name is .. */ 170 #define MAKEENTRY 0x0004000 /* entry is to be added to name cache */ 171 #define ISLASTCN 0x0008000 /* this is last component of pathname */ 172 #define ISSYMLINK 0x0010000 /* symlink needs interpretation */ 173 #define ISWHITEOUT 0x0020000 /* found whiteout */ 174 #define DOWHITEOUT 0x0040000 /* do whiteouts */ 175 #define REQUIREDIR 0x0080000 /* must be a directory */ 176 #define CREATEDIR 0x0200000 /* trailing slashes are ok */ 177 #define INRENAME 0x0400000 /* operation is a part of ``rename'' */ 178 #define PARAMASK 0x06fff00 /* mask of parameter descriptors */ 179 180 /* 181 * Initialization of an nameidata structure. 182 */ 183 #define NDINIT(ndp, op, flags, pathbuf) { \ 184 (ndp)->ni_cnd.cn_nameiop = op; \ 185 (ndp)->ni_cnd.cn_flags = flags; \ 186 (ndp)->ni_pathbuf = pathbuf; \ 187 (ndp)->ni_cnd.cn_cred = kauth_cred_get(); \ 188 } 189 #endif 190 191 /* 192 * This structure describes the elements in the cache of recent 193 * names looked up by namei. NCHNAMLEN is sized to make structure 194 * size a power of two to optimize malloc's. Minimum reasonable 195 * size is 15. 196 */ 197 198 #define NCHNAMLEN 31 /* maximum name segment length we bother with */ 199 200 /* 201 * Namecache entry. This structure is arranged so that frequently 202 * accessed and mostly read-only data is toward the front, with 203 * infrequently accessed data and the lock towards the rear. The 204 * lock is then more likely to be in a seperate cache line. 205 */ 206 struct namecache { 207 LIST_ENTRY(namecache) nc_hash; /* hash chain */ 208 LIST_ENTRY(namecache) nc_vhash; /* directory hash chain */ 209 struct vnode *nc_dvp; /* vnode of parent of name */ 210 struct vnode *nc_vp; /* vnode the name refers to */ 211 int nc_flags; /* copy of componentname's ISWHITEOUT */ 212 char nc_nlen; /* length of name */ 213 char nc_name[NCHNAMLEN]; /* segment name */ 214 void *nc_gcqueue; /* queue for garbage collection */ 215 TAILQ_ENTRY(namecache) nc_lru; /* psuedo-lru chain */ 216 LIST_ENTRY(namecache) nc_dvlist; 217 LIST_ENTRY(namecache) nc_vlist; 218 kmutex_t nc_lock; /* lock on this entry */ 219 int nc_hittime; /* last time scored a hit */ 220 }; 221 222 #ifdef _KERNEL 223 #include <sys/mallocvar.h> 224 #include <sys/pool.h> 225 226 struct mount; 227 struct cpu_info; 228 229 extern pool_cache_t pnbuf_cache; /* pathname buffer cache */ 230 231 #define PNBUF_GET() pool_cache_get(pnbuf_cache, PR_WAITOK) 232 #define PNBUF_PUT(pnb) pool_cache_put(pnbuf_cache, (pnb)) 233 234 /* 235 * Typesafe flags for namei_simple. 236 * 237 * This encoding is not optimal but serves the important purpose of 238 * not being type-compatible with the regular namei flags. 239 */ 240 struct namei_simple_flags_type; /* Opaque. */ 241 typedef const struct namei_simple_flags_type *namei_simple_flags_t; /* Gross. */ 242 extern const namei_simple_flags_t 243 NSM_NOFOLLOW_NOEMULROOT, 244 NSM_NOFOLLOW_TRYEMULROOT, 245 NSM_FOLLOW_NOEMULROOT, 246 NSM_FOLLOW_TRYEMULROOT; 247 248 /* 249 * namei_simple_* - the simple cases of namei, with no struct 250 * nameidata involved. 251 * 252 * namei_simple_kernel takes a kernel-space path as the first argument. 253 * namei_simple_user takes a user-space path as the first argument. 254 * 255 * A namei call can be converted to namei_simple_* if: 256 * - the second arg to NDINIT is LOOKUP; 257 * - it does not need the parent vnode, nd.ni_dvp; 258 * - the only flags it uses are (NO)FOLLOW and TRYEMULROOT; 259 * - it does not do anything else gross with the contents of nd. 260 */ 261 int namei_simple_kernel(const char *, namei_simple_flags_t, struct vnode **); 262 int namei_simple_user(const char *, namei_simple_flags_t, struct vnode **); 263 264 int namei(struct nameidata *); 265 uint32_t namei_hash(const char *, const char **); 266 int lookup_for_nfsd(struct nameidata *, struct vnode *, int neverfollow); 267 int lookup_for_nfsd_index(struct nameidata *); 268 int relookup(struct vnode *, struct vnode **, struct componentname *); 269 void cache_purge1(struct vnode *, const struct componentname *, int); 270 #define PURGE_PARENTS 1 271 #define PURGE_CHILDREN 2 272 #define cache_purge(vp) cache_purge1((vp), NULL, PURGE_PARENTS|PURGE_CHILDREN) 273 int cache_lookup(struct vnode *, struct vnode **, struct componentname *); 274 int cache_lookup_raw(struct vnode *, struct vnode **, 275 struct componentname *); 276 int cache_revlookup(struct vnode *, struct vnode **, char **, char *); 277 void cache_enter(struct vnode *, struct vnode *, struct componentname *); 278 void nchinit(void); 279 void nchreinit(void); 280 void cache_cpu_init(struct cpu_info *); 281 void cache_purgevfs(struct mount *); 282 void namecache_print(struct vnode *, void (*)(const char *, ...)); 283 284 #endif 285 286 /* 287 * Stats on usefulness of namei caches. 288 * XXX: should be 64-bit counters. 289 */ 290 struct nchstats { 291 long ncs_goodhits; /* hits that we can really use */ 292 long ncs_neghits; /* negative hits that we can use */ 293 long ncs_badhits; /* hits we must drop */ 294 long ncs_falsehits; /* hits with id mismatch */ 295 long ncs_miss; /* misses */ 296 long ncs_long; /* long names that ignore cache */ 297 long ncs_pass2; /* names found with passes == 2 */ 298 long ncs_2passes; /* number of times we attempt it */ 299 long ncs_revhits; /* reverse-cache hits */ 300 long ncs_revmiss; /* reverse-cache misses */ 301 }; 302 303 #ifdef _KERNEL 304 extern struct nchstats nchstats; 305 #endif 306 /* #endif !_SYS_NAMEI_H_ (generated by gennameih.awk) */ 307 308 /* Definitions match above, but with NAMEI_ prefix */ 309 #define NAMEI_LOOKUP 0 310 #define NAMEI_CREATE 1 311 #define NAMEI_DELETE 2 312 #define NAMEI_RENAME 3 313 #define NAMEI_OPMASK 3 314 #define NAMEI_LOCKLEAF 0x00000004 315 #define NAMEI_LOCKPARENT 0x00000008 316 #define NAMEI_TRYEMULROOT 0x00000010 317 #define NAMEI_NOCACHE 0x00000020 318 #define NAMEI_FOLLOW 0x00000040 319 #define NAMEI_NOFOLLOW 0x00000000 320 #define NAMEI_EMULROOTSET 0x00000080 321 #define NAMEI_NOCHROOT 0x01000000 322 #define NAMEI_MODMASK 0x010000fc 323 #define NAMEI_NOCROSSMOUNT 0x0000100 324 #define NAMEI_RDONLY 0x0000200 325 #define NAMEI_SAVESTART 0x0001000 326 #define NAMEI_ISDOTDOT 0x0002000 327 #define NAMEI_MAKEENTRY 0x0004000 328 #define NAMEI_ISLASTCN 0x0008000 329 #define NAMEI_ISSYMLINK 0x0010000 330 #define NAMEI_ISWHITEOUT 0x0020000 331 #define NAMEI_DOWHITEOUT 0x0040000 332 #define NAMEI_REQUIREDIR 0x0080000 333 #define NAMEI_CREATEDIR 0x0200000 334 #define NAMEI_INRENAME 0x0400000 335 #define NAMEI_PARAMASK 0x06fff00 336 337 #endif /* !_SYS_NAMEI_H_ */ 338