1 /* 2 * Copyright (c) 1985, 1989, 1991, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 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 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * @(#)namei.h 8.5 (Berkeley) 1/9/95 34 * $FreeBSD: src/sys/sys/namei.h,v 1.29.2.2 2001/09/30 21:12:54 luigi Exp $ 35 * $DragonFly: src/sys/sys/namei.h,v 1.4 2003/07/13 05:45:12 dillon Exp $ 36 */ 37 38 #ifndef _SYS_NAMEI_H_ 39 #define _SYS_NAMEI_H_ 40 41 #include <sys/queue.h> 42 #include <sys/uio.h> 43 44 #ifdef _KERNEL 45 #ifndef _SYS_THREAD_H_ 46 #include <sys/thread.h> 47 #endif 48 #ifndef _SYS_PROC_H_ 49 #include <sys/proc.h> 50 #endif 51 #endif 52 53 struct componentname { 54 /* 55 * Arguments to lookup. 56 */ 57 u_long cn_nameiop; /* namei operation */ 58 u_long cn_flags; /* flags to namei */ 59 struct thread *cn_td; /* process requesting lookup */ 60 struct ucred *cn_cred; /* credentials */ 61 /* 62 * Shared between lookup and commit routines. 63 */ 64 char *cn_pnbuf; /* pathname buffer */ 65 char *cn_nameptr; /* pointer to looked up name */ 66 long cn_namelen; /* length of looked up component */ 67 long cn_consume; /* chars to consume in lookup() */ 68 }; 69 70 /* 71 * Encapsulation of namei parameters. 72 */ 73 struct nameidata { 74 /* 75 * Arguments to namei/lookup. 76 */ 77 const char *ni_dirp; /* pathname pointer */ 78 enum uio_seg ni_segflg; /* location of pathname */ 79 /* u_long ni_nameiop; namei operation */ 80 /* u_long ni_flags; flags to namei */ 81 /* struct proc *ni_proc; process requesting lookup */ 82 /* 83 * Arguments to lookup. 84 */ 85 /* struct ucred *ni_cred; credentials */ 86 struct vnode *ni_startdir; /* starting directory */ 87 struct vnode *ni_rootdir; /* logical root directory */ 88 struct vnode *ni_topdir; /* logical top directory */ 89 /* 90 * Results: returned from/manipulated by lookup 91 */ 92 struct vnode *ni_vp; /* vnode of result */ 93 struct vnode *ni_dvp; /* vnode of intermediate directory */ 94 /* 95 * Shared between namei and lookup/commit routines. 96 */ 97 size_t ni_pathlen; /* remaining chars in path */ 98 char *ni_next; /* next location in pathname */ 99 u_long ni_loopcnt; /* count of symlinks encountered */ 100 /* 101 * Lookup parameters: this structure describes the subset of 102 * information from the nameidata structure that is passed 103 * through the VOP interface. 104 */ 105 struct componentname ni_cnd; 106 }; 107 108 #ifdef _KERNEL 109 /* 110 * namei operations 111 */ 112 #define LOOKUP 0 /* perform name lookup only */ 113 #define CREATE 1 /* setup for file creation */ 114 #define DELETE 2 /* setup for file deletion */ 115 #define RENAME 3 /* setup for file renaming */ 116 #define OPMASK 3 /* mask for operation */ 117 /* 118 * namei operational modifier flags, stored in ni_cnd.flags 119 */ 120 #define LOCKLEAF 0x0004 /* lock inode on return */ 121 #define LOCKPARENT 0x0008 /* want parent vnode returned locked */ 122 #define WANTPARENT 0x0010 /* want parent vnode returned unlocked */ 123 #define NOCACHE 0x0020 /* name must not be left in cache */ 124 #define FOLLOW 0x0040 /* follow symbolic links */ 125 #define NOOBJ 0x0080 /* don't create object */ 126 #define NOFOLLOW 0x0000 /* do not follow symbolic links (pseudo) */ 127 #define MODMASK 0x00fc /* mask of operational modifiers */ 128 /* 129 * Namei parameter descriptors. 130 * 131 * SAVENAME may be set by either the callers of namei or by VOP_LOOKUP. 132 * If the caller of namei sets the flag (for example execve wants to 133 * know the name of the program that is being executed), then it must 134 * free the buffer. If VOP_LOOKUP sets the flag, then the buffer must 135 * be freed by either the commit routine or the VOP_ABORT routine. 136 * SAVESTART is set only by the callers of namei. It implies SAVENAME 137 * plus the addition of saving the parent directory that contains the 138 * name in ni_startdir. It allows repeated calls to lookup for the 139 * name being sought. The caller is responsible for releasing the 140 * buffer and for vrele'ing ni_startdir. 141 */ 142 #define NOCROSSMOUNT 0x000100 /* do not cross mount points */ 143 #define RDONLY 0x000200 /* lookup with read-only semantics */ 144 #define HASBUF 0x000400 /* has allocated pathname buffer */ 145 #define SAVENAME 0x000800 /* save pathname buffer */ 146 #define SAVESTART 0x001000 /* save starting directory */ 147 #define ISDOTDOT 0x002000 /* current component name is .. */ 148 #define MAKEENTRY 0x004000 /* entry is to be added to name cache */ 149 #define ISLASTCN 0x008000 /* this is last component of pathname */ 150 #define ISSYMLINK 0x010000 /* symlink needs interpretation */ 151 #define ISWHITEOUT 0x020000 /* found whiteout */ 152 #define DOWHITEOUT 0x040000 /* do whiteouts */ 153 #define WILLBEDIR 0x080000 /* new files will be dirs; allow trailing / */ 154 #define ISUNICODE 0x100000 /* current component name is unicode*/ 155 #define PDIRUNLOCK 0x200000 /* file system lookup() unlocked parent dir */ 156 #define PARAMASK 0x1fff00 /* mask of parameter descriptors */ 157 /* 158 * Initialization of an nameidata structure. 159 */ 160 static void NDINIT __P((struct nameidata *, u_long, u_long, enum uio_seg, 161 const char *, struct thread *)); 162 static __inline void 163 NDINIT(struct nameidata *ndp, 164 u_long op, u_long flags, 165 enum uio_seg segflg, 166 const char *namep, 167 struct thread *td 168 ) { 169 struct proc *p = td->td_proc; 170 171 KKASSERT(p != NULL); 172 ndp->ni_cnd.cn_nameiop = op; 173 ndp->ni_cnd.cn_flags = flags; 174 ndp->ni_segflg = segflg; 175 ndp->ni_dirp = namep; 176 ndp->ni_cnd.cn_td = td; 177 ndp->ni_cnd.cn_cred = p->p_ucred; 178 } 179 180 #define NDF_NO_DVP_RELE 0x00000001 181 #define NDF_NO_DVP_UNLOCK 0x00000002 182 #define NDF_NO_DVP_PUT 0x00000003 183 #define NDF_NO_VP_RELE 0x00000004 184 #define NDF_NO_VP_UNLOCK 0x00000008 185 #define NDF_NO_VP_PUT 0x0000000c 186 #define NDF_NO_STARTDIR_RELE 0x00000010 187 #define NDF_NO_FREE_PNBUF 0x00000020 188 #define NDF_ONLY_PNBUF (~NDF_NO_FREE_PNBUF) 189 190 void NDFREE __P((struct nameidata *, const uint)); 191 192 int namei __P((struct nameidata *ndp)); 193 int lookup __P((struct nameidata *ndp)); 194 int relookup __P((struct vnode *dvp, struct vnode **vpp, 195 struct componentname *cnp)); 196 #endif 197 198 /* 199 * Stats on usefulness of namei caches. 200 */ 201 struct nchstats { 202 long ncs_goodhits; /* hits that we can really use */ 203 long ncs_neghits; /* negative hits that we can use */ 204 long ncs_badhits; /* hits we must drop */ 205 long ncs_falsehits; /* hits with id mismatch */ 206 long ncs_miss; /* misses */ 207 long ncs_long; /* long names that ignore cache */ 208 long ncs_pass2; /* names found with passes == 2 */ 209 long ncs_2passes; /* number of times we attempt it */ 210 }; 211 212 extern struct nchstats nchstats; 213 214 #endif /* !_SYS_NAMEI_H_ */ 215