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31 * @(#)namei.h 8.5 (Berkeley) 1/9/95
38 #include <sys/caprights.h>
39 #include <sys/filedesc.h>
40 #include <sys/queue.h>
43 struct componentname {
45 * Arguments to lookup.
47 u_long cn_nameiop; /* namei operation */
48 u_int64_t cn_flags; /* flags to namei */
49 struct thread *cn_thread;/* thread requesting lookup */
50 struct ucred *cn_cred; /* credentials */
51 int cn_lkflags; /* Lock flags LK_EXCLUSIVE or LK_SHARED */
53 * Shared between lookup and commit routines.
55 char *cn_pnbuf; /* pathname buffer */
56 char *cn_nameptr; /* pointer to looked up name */
57 long cn_namelen; /* length of looked up component */
60 struct nameicap_tracker;
61 TAILQ_HEAD(nameicap_tracker_head, nameicap_tracker);
64 * Encapsulation of namei parameters.
68 * Arguments to namei/lookup.
70 const char *ni_dirp; /* pathname pointer */
71 enum uio_seg ni_segflg; /* location of pathname */
72 cap_rights_t ni_rightsneeded; /* rights required to look up vnode */
74 * Arguments to lookup.
76 struct vnode *ni_startdir; /* starting directory */
77 struct vnode *ni_rootdir; /* logical root directory */
78 struct vnode *ni_topdir; /* logical top directory */
79 int ni_dirfd; /* starting directory for *at functions */
80 int ni_lcf; /* local call flags */
82 * Results: returned from namei
84 struct filecaps ni_filecaps; /* rights the *at base has */
86 * Results: returned from/manipulated by lookup
88 struct vnode *ni_vp; /* vnode of result */
89 struct vnode *ni_dvp; /* vnode of intermediate directory */
91 * Shared between namei and lookup/commit routines.
93 size_t ni_pathlen; /* remaining chars in path */
94 char *ni_next; /* next location in pathname */
95 u_int ni_loopcnt; /* count of symlinks encountered */
97 * Lookup parameters: this structure describes the subset of
98 * information from the nameidata structure that is passed
99 * through the VOP interface.
101 struct componentname ni_cnd;
102 struct nameicap_tracker_head ni_cap_tracker;
109 #define LOOKUP 0 /* perform name lookup only */
110 #define CREATE 1 /* setup for file creation */
111 #define DELETE 2 /* setup for file deletion */
112 #define RENAME 3 /* setup for file renaming */
113 #define OPMASK 3 /* mask for operation */
115 * namei operational modifier flags, stored in ni_cnd.flags
117 #define LOCKLEAF 0x0004 /* lock vnode on return */
118 #define LOCKPARENT 0x0008 /* want parent vnode returned locked */
119 #define WANTPARENT 0x0010 /* want parent vnode returned unlocked */
120 #define NOCACHE 0x0020 /* name must not be left in cache */
121 #define FOLLOW 0x0040 /* follow symbolic links */
122 #define LOCKSHARED 0x0100 /* Shared lock leaf */
123 #define NOFOLLOW 0x0000 /* do not follow symbolic links (pseudo) */
124 #define MODMASK 0x01fc /* mask of operational modifiers */
126 * Namei parameter descriptors.
128 * SAVENAME may be set by either the callers of namei or by VOP_LOOKUP.
129 * If the caller of namei sets the flag (for example execve wants to
130 * know the name of the program that is being executed), then it must
131 * free the buffer. If VOP_LOOKUP sets the flag, then the buffer must
132 * be freed by either the commit routine or the VOP_ABORT routine.
133 * SAVESTART is set only by the callers of namei. It implies SAVENAME
134 * plus the addition of saving the parent directory that contains the
135 * name in ni_startdir. It allows repeated calls to lookup for the
136 * name being sought. The caller is responsible for releasing the
137 * buffer and for vrele'ing ni_startdir.
139 #define RDONLY 0x00000200 /* lookup with read-only semantics */
140 #define HASBUF 0x00000400 /* has allocated pathname buffer */
141 #define SAVENAME 0x00000800 /* save pathname buffer */
142 #define SAVESTART 0x00001000 /* save starting directory */
143 #define ISDOTDOT 0x00002000 /* current component name is .. */
144 #define MAKEENTRY 0x00004000 /* entry is to be added to name cache */
145 #define ISLASTCN 0x00008000 /* this is last component of pathname */
146 #define ISSYMLINK 0x00010000 /* symlink needs interpretation */
147 #define ISWHITEOUT 0x00020000 /* found whiteout */
148 #define DOWHITEOUT 0x00040000 /* do whiteouts */
149 #define WILLBEDIR 0x00080000 /* new files will be dirs; allow trailing / */
150 #define ISUNICODE 0x00100000 /* current component name is unicode*/
151 #define ISOPEN 0x00200000 /* caller is opening; return a real vnode. */
152 #define NOCROSSMOUNT 0x00400000 /* do not cross mount points */
153 #define NOMACCHECK 0x00800000 /* do not perform MAC checks */
154 #define AUDITVNODE1 0x04000000 /* audit the looked up vnode information */
155 #define AUDITVNODE2 0x08000000 /* audit the looked up vnode information */
156 #define TRAILINGSLASH 0x10000000 /* path ended in a slash */
157 #define NOCAPCHECK 0x20000000 /* do not perform capability checks */
158 #define PARAMASK 0x3ffffe00 /* mask of parameter descriptors */
161 * Flags in ni_lcf, valid for the duration of the namei call.
163 #define NI_LCF_STRICTRELATIVE 0x0001 /* relative lookup only */
164 #define NI_LCF_CAP_DOTDOT 0x0002 /* ".." in strictrelative case */
167 * Initialization of a nameidata structure.
169 #define NDINIT(ndp, op, flags, segflg, namep, td) \
170 NDINIT_ALL(ndp, op, flags, segflg, namep, AT_FDCWD, NULL, 0, td)
171 #define NDINIT_AT(ndp, op, flags, segflg, namep, dirfd, td) \
172 NDINIT_ALL(ndp, op, flags, segflg, namep, dirfd, NULL, 0, td)
173 #define NDINIT_ATRIGHTS(ndp, op, flags, segflg, namep, dirfd, rightsp, td) \
174 NDINIT_ALL(ndp, op, flags, segflg, namep, dirfd, NULL, rightsp, td)
175 #define NDINIT_ATVP(ndp, op, flags, segflg, namep, vp, td) \
176 NDINIT_ALL(ndp, op, flags, segflg, namep, AT_FDCWD, vp, 0, td)
178 void NDINIT_ALL(struct nameidata *ndp, u_long op, u_long flags,
179 enum uio_seg segflg, const char *namep, int dirfd, struct vnode *startdir,
180 cap_rights_t *rightsp, struct thread *td);
182 #define NDF_NO_DVP_RELE 0x00000001
183 #define NDF_NO_DVP_UNLOCK 0x00000002
184 #define NDF_NO_DVP_PUT 0x00000003
185 #define NDF_NO_VP_RELE 0x00000004
186 #define NDF_NO_VP_UNLOCK 0x00000008
187 #define NDF_NO_VP_PUT 0x0000000c
188 #define NDF_NO_STARTDIR_RELE 0x00000010
189 #define NDF_NO_FREE_PNBUF 0x00000020
190 #define NDF_ONLY_PNBUF (~NDF_NO_FREE_PNBUF)
192 void NDFREE(struct nameidata *, const u_int);
194 int namei(struct nameidata *ndp);
195 int lookup(struct nameidata *ndp);
196 int relookup(struct vnode *dvp, struct vnode **vpp,
197 struct componentname *cnp);
201 * Stats on usefulness of namei caches.
204 long ncs_goodhits; /* hits that we can really use */
205 long ncs_neghits; /* negative hits that we can use */
206 long ncs_badhits; /* hits we must drop */
207 long ncs_falsehits; /* hits with id mismatch */
208 long ncs_miss; /* misses */
209 long ncs_long; /* long names that ignore cache */
210 long ncs_pass2; /* names found with passes == 2 */
211 long ncs_2passes; /* number of times we attempt it */
214 extern struct nchstats nchstats;
216 #endif /* !_SYS_NAMEI_H_ */