[apple/xnu.git] / bsd / sys / namei.h

/*
 * Copyright (c) 2000-2003 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
 * 
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. The rights granted to you under the License
 * may not be used to create, or enable the creation or redistribution of,
 * unlawful or unlicensed copies of an Apple operating system, or to
 * circumvent, violate, or enable the circumvention or violation of, any
 * terms of an Apple operating system software license agreement.
 * 
 * Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this file.
 * 
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
 * limitations under the License.
 * 
 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
 */
/* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */
/*
 * 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. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. 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	8.4 (Berkeley) 8/20/94
 */

#ifndef _SYS_NAMEI_H_
#define	_SYS_NAMEI_H_

#include <sys/appleapiopts.h>

#ifdef KERNEL
#define	LOCKLEAF	0x0004	/* lock inode on return */
#define	LOCKPARENT	0x0008	/* want parent vnode returned */
#define	WANTPARENT	0x0010	/* want parent vnode returned */
#endif


#ifdef BSD_KERNEL_PRIVATE

#include <sys/queue.h>
#include <sys/uio.h>
#include <sys/vnode.h>
#include <sys/mount.h>
#include <sys/filedesc.h>

#define PATHBUFLEN	256

/*
 * Encapsulation of namei parameters.
 */
struct nameidata {
	/*
	 * Arguments to namei/lookup.
	 */
	user_addr_t ni_dirp;		/* pathname pointer */
	enum	uio_seg ni_segflg;	/* location of pathname */
	/*
	 * Arguments to lookup.
	 */
	struct	vnode *ni_startdir;	/* starting directory */
	struct	vnode *ni_rootdir;	/* logical root directory */
        struct  vnode *ni_usedvp;       /* directory passed in via USEDVP */
	/*
	 * 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.
	 */
	u_int	ni_pathlen;		/* remaining chars in path */
	char	*ni_next;		/* next location in pathname */
        char	ni_pathbuf[PATHBUFLEN];
	u_long	ni_loopcnt;		/* count of symlinks encountered */

	struct componentname ni_cnd;
};

#ifdef KERNEL
/*
 * namei operational modifier flags, stored in ni_cnd.flags
 */
#define	NOCACHE		0x0020	/* name must not be left in cache */
#define	NOFOLLOW	0x0000	/* do not follow symbolic links (pseudo) */
#define	SHAREDLEAF	0x0080	/* OK to have shared leaf lock */
#define	MODMASK		0x00fc	/* mask of operational modifiers */
/*
 * Namei parameter descriptors.
 *
 * SAVESTART is set only by the callers of namei. It implies SAVENAME
 * plus the addition of saving the parent directory that contains the
 * name in ni_startdir. It allows repeated calls to lookup for the
 * name being sought. The caller is responsible for releasing the
 * buffer and for vrele'ing ni_startdir.
 */
#define	NOCROSSMOUNT	0x00000100 /* do not cross mount points */
#define	RDONLY		0x00000200 /* lookup with read-only semantics */
#define	HASBUF		0x00000400 /* has allocated pathname buffer */
#define	SAVENAME	0x00000800 /* save pathanme buffer */
#define	SAVESTART	0x00001000 /* save starting directory */
#define	ISSYMLINK	0x00010000 /* symlink needs interpretation */
#define DONOTAUTH	0x00020000 /* do not authorize during lookup */
#define	WILLBEDIR	0x00080000 /* new files will be dirs; allow trailing / */
#define	AUDITVNPATH1	0x00100000 /* audit the path/vnode info */
#define	AUDITVNPATH2	0x00200000 /* audit the path/vnode info */
#define	USEDVP		0x00400000 /* start the lookup at ndp.ni_dvp */
#define	PARAMASK	0x003fff00 /* mask of parameter descriptors */
#define FSNODELOCKHELD	0x01000000

/*
 * Initialization of an nameidata structure.
 */
#define NDINIT(ndp, op, flags, segflg, namep, ctx) { \
	(ndp)->ni_cnd.cn_nameiop = op; \
	(ndp)->ni_cnd.cn_flags = flags; \
	if ((segflg) == UIO_USERSPACE) { \
		(ndp)->ni_segflg = ((IS_64BIT_PROCESS(vfs_context_proc(ctx))) ? UIO_USERSPACE64 : UIO_USERSPACE32); \
	} \
	else if ((segflg) == UIO_SYSSPACE) { \
		(ndp)->ni_segflg = UIO_SYSSPACE32; \
	} \
	else { \
		(ndp)->ni_segflg = segflg; \
	} \
	(ndp)->ni_dirp = namep; \
	(ndp)->ni_cnd.cn_context = ctx; \
}
#endif /* KERNEL */

/*
 * This structure describes the elements in the cache of recent
 * names looked up by namei.
 */

#define	NCHNAMLEN	31	/* maximum name segment length we bother with */
#define NCHASHMASK	0x7fffffff

struct	namecache {
	TAILQ_ENTRY(namecache)	nc_entry;	/* chain of all entries */
	LIST_ENTRY(namecache)	nc_hash;	/* hash chain */
        LIST_ENTRY(namecache)	nc_child;	/* chain of ncp's that are children of a vp */
        union {
	  LIST_ENTRY(namecache)	 nc_link;	/* chain of ncp's that 'name' a vp */
	  TAILQ_ENTRY(namecache) nc_negentry;	/* chain of ncp's that 'name' a vp */
	} nc_un;
	vnode_t			nc_dvp;		/* vnode of parent of name */
	vnode_t			nc_vp;		/* vnode the name refers to */
        unsigned int		nc_whiteout:1,	/* name has whiteout applied */
	                        nc_hashval:31;	/* hashval of stringname */
	char		*	nc_name;	/* pointer to segment name in string cache */
};


#ifdef KERNEL

int	namei(struct nameidata *ndp);
void	nameidone(struct nameidata *);
int	lookup(struct nameidata *ndp);
int	relookup(struct vnode *dvp, struct vnode **vpp,
		struct componentname *cnp);

/*
 * namecache function prototypes
 */
void    cache_purgevfs(mount_t mp);
int		cache_lookup_path(struct nameidata *ndp, struct componentname *cnp, vnode_t dp,
			  vfs_context_t context, int *trailing_slash, int *dp_authorized);

void	vnode_cache_credentials(vnode_t vp, vfs_context_t context);
void	vnode_uncache_credentials(vnode_t vp);
int		reverse_lookup(vnode_t start_vp, vnode_t *lookup_vpp, 
				struct filedesc *fdp, vfs_context_t context, int *dp_authorized);

#endif /* KERNEL */

/*
 * Stats on usefulness of namei caches.
 */
struct	nchstats {
        long	ncs_negtotal;
	long	ncs_goodhits;		/* hits that we can really use */
	long	ncs_neghits;		/* negative hits that we can use */
	long	ncs_badhits;		/* hits we must drop */
	long	ncs_miss;		/* misses */
	long	ncs_pass2;		/* names found with passes == 2 */
	long	ncs_2passes;		/* number of times we attempt it */
        long	ncs_stolen;
        long	ncs_enters;
        long	ncs_deletes;
        long	ncs_badvid;
};
#endif /* BSD_KERNEL_PRIVATE */

#endif /* !_SYS_NAMEI_H_ */
Commit	Line	Data
1c79356b	1	/*
55e303ae	2	* Copyright (c) 2000-2003 Apple Computer, Inc. All rights reserved.
1c79356b	3	*
8f6c56a5	4	* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
1c79356b	5	*
8f6c56a5 A	6	* This file contains Original Code and/or Modifications of Original Code
	7	* as defined in and that are subject to the Apple Public Source License
	8	* Version 2.0 (the 'License'). You may not use this file except in
	9	* compliance with the License. The rights granted to you under the License
	10	* may not be used to create, or enable the creation or redistribution of,
	11	* unlawful or unlicensed copies of an Apple operating system, or to
	12	* circumvent, violate, or enable the circumvention or violation of, any
	13	* terms of an Apple operating system software license agreement.
	14	*
	15	* Please obtain a copy of the License at
	16	* http://www.opensource.apple.com/apsl/ and read it before using this file.
	17	*
	18	* The Original Code and all software distributed under the License are
	19	* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
	20	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
	21	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
	22	* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
	23	* Please see the License for the specific language governing rights and
8ad349bb	24	* limitations under the License.
8f6c56a5 A	25	*
8f6c56a5 A	26	* @APPLE_OSREFERENCE_LICENSE_HEADER_END@
1c79356b A	27	*/
	28	/* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */
	29	/*
	30	* Copyright (c) 1985, 1989, 1991, 1993
	31	* The Regents of the University of California. All rights reserved.
	32	*
	33	* Redistribution and use in source and binary forms, with or without
	34	* modification, are permitted provided that the following conditions
	35	* are met:
	36	* 1. Redistributions of source code must retain the above copyright
	37	* notice, this list of conditions and the following disclaimer.
	38	* 2. Redistributions in binary form must reproduce the above copyright
	39	* notice, this list of conditions and the following disclaimer in the
	40	* documentation and/or other materials provided with the distribution.
	41	* 3. All advertising materials mentioning features or use of this software
	42	* must display the following acknowledgement:
	43	* This product includes software developed by the University of
	44	* California, Berkeley and its contributors.
	45	* 4. Neither the name of the University nor the names of its contributors
	46	* may be used to endorse or promote products derived from this software
	47	* without specific prior written permission.
	48	*
	49	* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	50	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	51	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	52	* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	53	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	54	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	55	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	56	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	57	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	58	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	59	* SUCH DAMAGE.
	60	*
	61	* @(#)namei.h 8.4 (Berkeley) 8/20/94
	62	*/
	63
	64	#ifndef _SYS_NAMEI_H_
	65	#define _SYS_NAMEI_H_
	66
9bccf70c A	67	#include <sys/appleapiopts.h>
9bccf70c A	68
91447636 A	69	#ifdef KERNEL
	70	#define LOCKLEAF 0x0004 /* lock inode on return */
	71	#define LOCKPARENT 0x0008 /* want parent vnode returned */
	72	#define WANTPARENT 0x0010 /* want parent vnode returned */
	73	#endif
	74
	75
	76	#ifdef BSD_KERNEL_PRIVATE
9bccf70c	77
1c79356b A	78	#include <sys/queue.h>
1c79356b A	79	#include <sys/uio.h>
91447636 A	80	#include <sys/vnode.h>
	81	#include <sys/mount.h>
	82	#include <sys/filedesc.h>
1c79356b	83
91447636	84	#define PATHBUFLEN 256
1c79356b A	85
	86	/*
	87	* Encapsulation of namei parameters.
	88	*/
	89	struct nameidata {
	90	/*
	91	* Arguments to namei/lookup.
	92	*/
91447636	93	user_addr_t ni_dirp; /* pathname pointer */
1c79356b	94	enum uio_seg ni_segflg; /* location of pathname */
1c79356b A	95	/*
	96	* Arguments to lookup.
	97	*/
1c79356b A	98	struct vnode ni_startdir; / starting directory */
1c79356b A	99	struct vnode ni_rootdir; / logical root directory */
91447636	100	struct vnode ni_usedvp; / directory passed in via USEDVP */
1c79356b A	101	/*
	102	* Results: returned from/manipulated by lookup
	103	*/
	104	struct vnode ni_vp; / vnode of result */
	105	struct vnode ni_dvp; / vnode of intermediate directory */
	106	/*
	107	* Shared between namei and lookup/commit routines.
	108	*/
	109	u_int ni_pathlen; /* remaining chars in path */
	110	char ni_next; / next location in pathname */
91447636	111	char ni_pathbuf[PATHBUFLEN];
1c79356b	112	u_long ni_loopcnt; /* count of symlinks encountered */
91447636	113
1c79356b A	114	struct componentname ni_cnd;
	115	};
	116
	117	#ifdef KERNEL
1c79356b A	118	/*
	119	* namei operational modifier flags, stored in ni_cnd.flags
	120	*/
1c79356b	121	#define NOCACHE 0x0020 /* name must not be left in cache */
1c79356b	122	#define NOFOLLOW 0x0000 /* do not follow symbolic links (pseudo) */
55e303ae	123	#define SHAREDLEAF 0x0080 /* OK to have shared leaf lock */
1c79356b A	124	#define MODMASK 0x00fc /* mask of operational modifiers */
	125	/*
	126	* Namei parameter descriptors.
	127	*
1c79356b A	128	* SAVESTART is set only by the callers of namei. It implies SAVENAME
	129	* plus the addition of saving the parent directory that contains the
	130	* name in ni_startdir. It allows repeated calls to lookup for the
	131	* name being sought. The caller is responsible for releasing the
	132	* buffer and for vrele'ing ni_startdir.
	133	*/
91447636 A	134	#define NOCROSSMOUNT 0x00000100 /* do not cross mount points */
	135	#define RDONLY 0x00000200 /* lookup with read-only semantics */
	136	#define HASBUF 0x00000400 /* has allocated pathname buffer */
	137	#define SAVENAME 0x00000800 /* save pathanme buffer */
	138	#define SAVESTART 0x00001000 /* save starting directory */
	139	#define ISSYMLINK 0x00010000 /* symlink needs interpretation */
	140	#define DONOTAUTH 0x00020000 /* do not authorize during lookup */
	141	#define WILLBEDIR 0x00080000 /* new files will be dirs; allow trailing / */
	142	#define AUDITVNPATH1 0x00100000 /* audit the path/vnode info */
	143	#define AUDITVNPATH2 0x00200000 /* audit the path/vnode info */
	144	#define USEDVP 0x00400000 /* start the lookup at ndp.ni_dvp */
	145	#define PARAMASK 0x003fff00 /* mask of parameter descriptors */
	146	#define FSNODELOCKHELD 0x01000000
	147
1c79356b A	148	/*
	149	* Initialization of an nameidata structure.
	150	*/
91447636	151	#define NDINIT(ndp, op, flags, segflg, namep, ctx) { \
1c79356b A	152	(ndp)->ni_cnd.cn_nameiop = op; \
1c79356b A	153	(ndp)->ni_cnd.cn_flags = flags; \
91447636 A	154	if ((segflg) == UIO_USERSPACE) { \
	155	(ndp)->ni_segflg = ((IS_64BIT_PROCESS(vfs_context_proc(ctx))) ? UIO_USERSPACE64 : UIO_USERSPACE32); \
	156	} \
	157	else if ((segflg) == UIO_SYSSPACE) { \
	158	(ndp)->ni_segflg = UIO_SYSSPACE32; \
	159	} \
	160	else { \
	161	(ndp)->ni_segflg = segflg; \
	162	} \
1c79356b	163	(ndp)->ni_dirp = namep; \
91447636	164	(ndp)->ni_cnd.cn_context = ctx; \
1c79356b A	165	}
	166	#endif /* KERNEL */
	167
	168	/*
	169	* This structure describes the elements in the cache of recent
91447636	170	* names looked up by namei.
1c79356b A	171	*/
	172
	173	#define NCHNAMLEN 31 /* maximum name segment length we bother with */
91447636	174	#define NCHASHMASK 0x7fffffff
1c79356b A	175
1c79356b A	176	struct namecache {
91447636 A	177	TAILQ_ENTRY(namecache) nc_entry; /* chain of all entries */
	178	LIST_ENTRY(namecache) nc_hash; /* hash chain */
	179	LIST_ENTRY(namecache) nc_child; /* chain of ncp's that are children of a vp */
	180	union {
	181	LIST_ENTRY(namecache) nc_link; /* chain of ncp's that 'name' a vp */
	182	TAILQ_ENTRY(namecache) nc_negentry; /* chain of ncp's that 'name' a vp */
	183	} nc_un;
	184	vnode_t nc_dvp; /* vnode of parent of name */
	185	vnode_t nc_vp; /* vnode the name refers to */
	186	unsigned int nc_whiteout:1, /* name has whiteout applied */
	187	nc_hashval:31; /* hashval of stringname */
	188	char * nc_name; /* pointer to segment name in string cache */
1c79356b A	189	};
1c79356b A	190
91447636	191
1c79356b	192	#ifdef KERNEL
55e303ae	193
91447636 A	194	int namei(struct nameidata *ndp);
	195	void nameidone(struct nameidata *);
	196	int lookup(struct nameidata *ndp);
	197	int relookup(struct vnode dvp, struct vnode *vpp,
	198	struct componentname *cnp);
	199
	200	/*
	201	* namecache function prototypes
	202	*/
	203	void cache_purgevfs(mount_t mp);
	204	int cache_lookup_path(struct nameidata ndp, struct componentname cnp, vnode_t dp,
	205	vfs_context_t context, int trailing_slash, int dp_authorized);
	206
	207	void vnode_cache_credentials(vnode_t vp, vfs_context_t context);
	208	void vnode_uncache_credentials(vnode_t vp);
	209	int reverse_lookup(vnode_t start_vp, vnode_t *lookup_vpp,
	210	struct filedesc fdp, vfs_context_t context, int dp_authorized);
55e303ae	211
1c79356b A	212	#endif /* KERNEL */
	213
	214	/*
	215	* Stats on usefulness of namei caches.
	216	*/
	217	struct nchstats {
21362eb3	218	long ncs_negtotal;
1c79356b A	219	long ncs_goodhits; /* hits that we can really use */
	220	long ncs_neghits; /* negative hits that we can use */
	221	long ncs_badhits; /* hits we must drop */
1c79356b	222	long ncs_miss; /* misses */
1c79356b A	223	long ncs_pass2; /* names found with passes == 2 */
1c79356b A	224	long ncs_2passes; /* number of times we attempt it */
91447636 A	225	long ncs_stolen;
	226	long ncs_enters;
	227	long ncs_deletes;
	228	long ncs_badvid;
1c79356b	229	};
91447636	230	#endif /* BSD_KERNEL_PRIVATE */
9bccf70c	231
1c79356b	232	#endif /* !_SYS_NAMEI_H_ */