2 * Copyright (c) 1985, 1989, 1991, 1993
3 * The Regents of the University of California. All rights reserved.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 4. Neither the name of the University nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * @(#)namei.h 8.5 (Berkeley) 1/9/95
36 #include <sys/filedesc.h>
37 #include <sys/queue.h>
40 struct componentname {
42 * Arguments to lookup.
44 u_long cn_nameiop; /* namei operation */
45 u_int64_t cn_flags; /* flags to namei */
46 struct thread *cn_thread;/* thread requesting lookup */
47 struct ucred *cn_cred; /* credentials */
48 int cn_lkflags; /* Lock flags LK_EXCLUSIVE or LK_SHARED */
50 * Shared between lookup and commit routines.
52 char *cn_pnbuf; /* pathname buffer */
53 char *cn_nameptr; /* pointer to looked up name */
54 long cn_namelen; /* length of looked up component */
55 long cn_consume; /* chars to consume in lookup() */
59 * Encapsulation of namei parameters.
63 * Arguments to namei/lookup.
65 const char *ni_dirp; /* pathname pointer */
66 enum uio_seg ni_segflg; /* location of pathname */
67 cap_rights_t ni_rightsneeded; /* rights required to look up vnode */
69 * Arguments to lookup.
71 struct vnode *ni_startdir; /* starting directory */
72 struct vnode *ni_rootdir; /* logical root directory */
73 struct vnode *ni_topdir; /* logical top directory */
74 int ni_dirfd; /* starting directory for *at functions */
75 int ni_strictrelative; /* relative lookup only; no '..' */
77 * Results: returned from namei
79 struct filecaps ni_filecaps; /* rights the *at base has */
81 * Results: returned from/manipulated by lookup
83 struct vnode *ni_vp; /* vnode of result */
84 struct vnode *ni_dvp; /* vnode of intermediate directory */
86 * Shared between namei and lookup/commit routines.
88 size_t ni_pathlen; /* remaining chars in path */
89 char *ni_next; /* next location in pathname */
90 u_int ni_loopcnt; /* count of symlinks encountered */
92 * Lookup parameters: this structure describes the subset of
93 * information from the nameidata structure that is passed
94 * through the VOP interface.
96 struct componentname ni_cnd;
103 #define LOOKUP 0 /* perform name lookup only */
104 #define CREATE 1 /* setup for file creation */
105 #define DELETE 2 /* setup for file deletion */
106 #define RENAME 3 /* setup for file renaming */
107 #define OPMASK 3 /* mask for operation */
109 * namei operational modifier flags, stored in ni_cnd.flags
111 #define LOCKLEAF 0x0004 /* lock vnode on return */
112 #define LOCKPARENT 0x0008 /* want parent vnode returned locked */
113 #define WANTPARENT 0x0010 /* want parent vnode returned unlocked */
114 #define NOCACHE 0x0020 /* name must not be left in cache */
115 #define FOLLOW 0x0040 /* follow symbolic links */
116 #define LOCKSHARED 0x0100 /* Shared lock leaf */
117 #define NOFOLLOW 0x0000 /* do not follow symbolic links (pseudo) */
118 #define MODMASK 0x01fc /* mask of operational modifiers */
120 * Namei parameter descriptors.
122 * SAVENAME may be set by either the callers of namei or by VOP_LOOKUP.
123 * If the caller of namei sets the flag (for example execve wants to
124 * know the name of the program that is being executed), then it must
125 * free the buffer. If VOP_LOOKUP sets the flag, then the buffer must
126 * be freed by either the commit routine or the VOP_ABORT routine.
127 * SAVESTART is set only by the callers of namei. It implies SAVENAME
128 * plus the addition of saving the parent directory that contains the
129 * name in ni_startdir. It allows repeated calls to lookup for the
130 * name being sought. The caller is responsible for releasing the
131 * buffer and for vrele'ing ni_startdir.
133 #define RDONLY 0x00000200 /* lookup with read-only semantics */
134 #define HASBUF 0x00000400 /* has allocated pathname buffer */
135 #define SAVENAME 0x00000800 /* save pathname buffer */
136 #define SAVESTART 0x00001000 /* save starting directory */
137 #define ISDOTDOT 0x00002000 /* current component name is .. */
138 #define MAKEENTRY 0x00004000 /* entry is to be added to name cache */
139 #define ISLASTCN 0x00008000 /* this is last component of pathname */
140 #define ISSYMLINK 0x00010000 /* symlink needs interpretation */
141 #define ISWHITEOUT 0x00020000 /* found whiteout */
142 #define DOWHITEOUT 0x00040000 /* do whiteouts */
143 #define WILLBEDIR 0x00080000 /* new files will be dirs; allow trailing / */
144 #define ISUNICODE 0x00100000 /* current component name is unicode*/
145 #define ISOPEN 0x00200000 /* caller is opening; return a real vnode. */
146 #define NOCROSSMOUNT 0x00400000 /* do not cross mount points */
147 #define NOMACCHECK 0x00800000 /* do not perform MAC checks */
148 #define AUDITVNODE1 0x04000000 /* audit the looked up vnode information */
149 #define AUDITVNODE2 0x08000000 /* audit the looked up vnode information */
150 #define TRAILINGSLASH 0x10000000 /* path ended in a slash */
151 #define NOCAPCHECK 0x20000000 /* do not perform capability checks */
152 #define PARAMASK 0x3ffffe00 /* mask of parameter descriptors */
155 * Initialization of a nameidata structure.
157 #define NDINIT(ndp, op, flags, segflg, namep, td) \
158 NDINIT_ALL(ndp, op, flags, segflg, namep, AT_FDCWD, NULL, 0, td)
159 #define NDINIT_AT(ndp, op, flags, segflg, namep, dirfd, td) \
160 NDINIT_ALL(ndp, op, flags, segflg, namep, dirfd, NULL, 0, td)
161 #define NDINIT_ATRIGHTS(ndp, op, flags, segflg, namep, dirfd, rights, td) \
162 NDINIT_ALL(ndp, op, flags, segflg, namep, dirfd, NULL, rights, td)
163 #define NDINIT_ATVP(ndp, op, flags, segflg, namep, vp, td) \
164 NDINIT_ALL(ndp, op, flags, segflg, namep, AT_FDCWD, vp, 0, td)
167 NDINIT_ALL(struct nameidata *ndp,
168 u_long op, u_long flags,
172 struct vnode *startdir,
176 ndp->ni_cnd.cn_nameiop = op;
177 ndp->ni_cnd.cn_flags = flags;
178 ndp->ni_segflg = segflg;
179 ndp->ni_dirp = namep;
180 ndp->ni_dirfd = dirfd;
181 ndp->ni_startdir = startdir;
182 ndp->ni_strictrelative = 0;
183 ndp->ni_rightsneeded = rights;
184 filecaps_init(&ndp->ni_filecaps);
185 ndp->ni_cnd.cn_thread = td;
188 #define NDF_NO_DVP_RELE 0x00000001
189 #define NDF_NO_DVP_UNLOCK 0x00000002
190 #define NDF_NO_DVP_PUT 0x00000003
191 #define NDF_NO_VP_RELE 0x00000004
192 #define NDF_NO_VP_UNLOCK 0x00000008
193 #define NDF_NO_VP_PUT 0x0000000c
194 #define NDF_NO_STARTDIR_RELE 0x00000010
195 #define NDF_NO_FREE_PNBUF 0x00000020
196 #define NDF_ONLY_PNBUF (~NDF_NO_FREE_PNBUF)
198 void NDFREE(struct nameidata *, const u_int);
200 int namei(struct nameidata *ndp);
201 int lookup(struct nameidata *ndp);
202 int relookup(struct vnode *dvp, struct vnode **vpp,
203 struct componentname *cnp);
207 * Stats on usefulness of namei caches.
210 long ncs_goodhits; /* hits that we can really use */
211 long ncs_neghits; /* negative hits that we can use */
212 long ncs_badhits; /* hits we must drop */
213 long ncs_falsehits; /* hits with id mismatch */
214 long ncs_miss; /* misses */
215 long ncs_long; /* long names that ignore cache */
216 long ncs_pass2; /* names found with passes == 2 */
217 long ncs_2passes; /* number of times we attempt it */
220 extern struct nchstats nchstats;
222 #endif /* !_SYS_NAMEI_H_ */