xref: /freebsd/sys/fs/devfs/devfs.h (revision 29363fb446372cb3f10bc98664e9767c53fbb457)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 1992, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  * Copyright (c) 2000
7  *	Poul-Henning Kamp.  All rights reserved.
8  * Copyright (c) 2002
9  *	Dima Dorfman.  All rights reserved.
10  *
11  * This code is derived from software donated to Berkeley by
12  * Jan-Simon Pendry.
13  *
14  * Redistribution and use in source and binary forms, with or without
15  * modification, are permitted provided that the following conditions
16  * are met:
17  * 1. Redistributions of source code must retain the above copyright
18  *    notice, this list of conditions and the following disclaimer.
19  * 2. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  * From: FreeBSD: src/sys/miscfs/kernfs/kernfs.h 1.14
35  */
36 
37 #ifndef _FS_DEVFS_DEVFS_H_
38 #define	_FS_DEVFS_DEVFS_H_
39 
40 #define	DEVFS_MAGIC	0xdb0a087a
41 
42 /*
43  * Identifiers.  The ruleset and rule numbers are 16-bit values.  The
44  * "rule ID" is a combination of the ruleset and rule number; it
45  * should be able to univocally describe a rule in the system.  In
46  * this implementation, the upper 16 bits of the rule ID is the
47  * ruleset number; the lower 16 bits, the rule number within the
48  * aforementioned ruleset.
49  */
50 typedef uint16_t devfs_rnum;
51 typedef uint16_t devfs_rsnum;
52 typedef uint32_t devfs_rid;
53 
54 /*
55  * Identifier manipulators.
56  */
57 #define	rid2rsn(rid)	((rid) >> 16)
58 #define	rid2rn(rid)	((rid) & 0xffff)
59 #define	mkrid(rsn, rn)	((rn) | ((rsn) << 16))
60 
61 /*
62  * Plain DEVFS rule.  This gets shared between kernel and userland
63  * verbatim, so it shouldn't contain any pointers or other kernel- or
64  * userland-specific values.
65  */
66 struct devfs_rule {
67 	uint32_t dr_magic;			/* Magic number. */
68 	devfs_rid dr_id;			/* Identifier. */
69 
70 	/*
71 	 * Conditions under which this rule should be applied.  These
72 	 * are ANDed together since OR can be simulated by using
73 	 * multiple rules.  dr_icond determines which of the other
74 	 * variables we should process.
75 	 */
76 	int	dr_icond;
77 #define	DRC_DSWFLAGS	0x001
78 #define	DRC_PATHPTRN	0x002
79 	int	dr_dswflags;			/* cdevsw flags to match. */
80 #define	DEVFS_MAXPTRNLEN	200
81 	char	dr_pathptrn[DEVFS_MAXPTRNLEN];	/* Pattern to match path. */
82 
83 	/*
84 	 * Things to change.  dr_iacts determines which of the other
85 	 * variables we should process.
86 	 */
87 	int	dr_iacts;
88 #define	DRA_BACTS	0x001
89 #define	DRA_UID		0x002
90 #define	DRA_GID		0x004
91 #define	DRA_MODE	0x008
92 #define	DRA_INCSET	0x010
93 	int	dr_bacts;			/* Boolean (on/off) action. */
94 #define	DRB_HIDE	0x001			/* Hide entry (DE_WHITEOUT). */
95 #define	DRB_UNHIDE	0x002			/* Unhide entry. */
96 	uid_t	dr_uid;
97 	gid_t	dr_gid;
98 	mode_t	dr_mode;
99 	devfs_rsnum dr_incset;			/* Included ruleset. */
100 };
101 
102 /*
103  * Rule-related ioctls.
104  */
105 #define	DEVFSIO_RADD		_IOWR('D', 0, struct devfs_rule)
106 #define	DEVFSIO_RDEL		_IOW('D', 1, devfs_rid)
107 #define	DEVFSIO_RAPPLY		_IOW('D', 2, struct devfs_rule)
108 #define	DEVFSIO_RAPPLYID	_IOW('D', 3, devfs_rid)
109 #define	DEVFSIO_RGETNEXT       	_IOWR('D', 4, struct devfs_rule)
110 
111 #define	DEVFSIO_SUSE		_IOW('D', 10, devfs_rsnum)
112 #define	DEVFSIO_SAPPLY		_IOW('D', 11, devfs_rsnum)
113 #define	DEVFSIO_SGETNEXT	_IOWR('D', 12, devfs_rsnum)
114 
115 /* XXX: DEVFSIO_RS_GET_INFO for refcount, active if any, etc. */
116 
117 #ifdef _KERNEL
118 
119 #ifdef MALLOC_DECLARE
120 MALLOC_DECLARE(M_DEVFS);
121 #endif
122 
123 #endif /* _KERNEL */
124 
125 struct componentname;
126 
127 TAILQ_HEAD(devfs_dlist_head, devfs_dirent);
128 
129 struct devfs_dirent {
130 	struct cdev_priv	*de_cdp;
131 	int			de_inode;
132 	int			de_flags;
133 #define	DE_WHITEOUT	0x01
134 #define	DE_DOT		0x02
135 #define	DE_DOTDOT	0x04
136 #define	DE_DOOMED	0x08
137 #define	DE_COVERED	0x10
138 #define	DE_USER		0x20
139 	int			de_holdcnt;
140 	struct dirent 		*de_dirent;
141 	TAILQ_ENTRY(devfs_dirent) de_list;
142 	struct devfs_dlist_head	de_dlist;
143 	struct devfs_dirent	*de_dir;
144 	int			de_links;
145 	mode_t			de_mode;
146 	uid_t			de_uid;
147 	gid_t			de_gid;
148 	struct label		*de_label;
149 	struct timespec 	de_atime;
150 	struct timespec 	de_mtime;
151 	struct timespec 	de_ctime;
152 	struct vnode 		*de_vnode;
153 	char 			*de_symlink;
154 	int			de_usecount;
155 };
156 
157 #include <sys/_lock.h>
158 #include <sys/_sx.h>
159 
160 struct devfs_mount {
161 	u_int			dm_idx;
162 	struct mount		*dm_mount;
163 	struct devfs_dirent	*dm_rootdir;
164 	unsigned		dm_generation;
165 	int			dm_holdcnt;
166 	struct sx		dm_lock;
167 	devfs_rsnum		dm_ruleset;
168 };
169 
170 #define DEVFS_ROOTINO 2
171 
172 #ifdef _KERNEL
173 
174 extern unsigned devfs_rule_depth;
175 
176 #define VFSTODEVFS(mp)	((struct devfs_mount *)((mp)->mnt_data))
177 
178 #define DEVFS_DE_HOLD(de)	((de)->de_holdcnt++)
179 #define DEVFS_DE_DROP(de)	(--(de)->de_holdcnt == 0)
180 
181 #define DEVFS_DMP_HOLD(dmp)	((dmp)->dm_holdcnt++)
182 #define DEVFS_DMP_DROP(dmp)	(--(dmp)->dm_holdcnt == 0)
183 
184 #define	DEVFS_DEL_NORECURSE	0x01
185 
186 void	devfs_rules_apply(struct devfs_mount *, struct devfs_dirent *);
187 void	devfs_rules_cleanup(struct devfs_mount *);
188 int	devfs_rules_ioctl(struct devfs_mount *, u_long, caddr_t,
189 	    struct thread *);
190 void	devfs_ruleset_set(devfs_rsnum rsnum, struct devfs_mount *dm);
191 void	devfs_ruleset_apply(struct devfs_mount *dm);
192 int	devfs_allocv(struct devfs_dirent *, struct mount *, int,
193 	    struct vnode **);
194 char	*devfs_fqpn(char *, struct devfs_mount *, struct devfs_dirent *,
195 	    struct componentname *);
196 void	devfs_delete(struct devfs_mount *, struct devfs_dirent *, int);
197 void	devfs_dirent_free(struct devfs_dirent *);
198 int	devfs_populate_needed(struct devfs_mount *dm);
199 void	devfs_populate(struct devfs_mount *);
200 void	devfs_cleanup(struct devfs_mount *);
201 void	devfs_unmount_final(struct devfs_mount *);
202 struct devfs_dirent	*devfs_newdirent(char *, int);
203 struct devfs_dirent	*devfs_parent_dirent(struct devfs_dirent *);
204 struct devfs_dirent	*devfs_vmkdir(struct devfs_mount *, char *, int,
205 			    struct devfs_dirent *, u_int);
206 struct devfs_dirent	*devfs_find(struct devfs_dirent *, const char *, int,
207 			    int);
208 
209 void	devfs_ctty_ref(struct vnode *);
210 void	devfs_ctty_unref(struct vnode *);
211 int	devfs_usecount(struct vnode *);
212 
213 #endif /* _KERNEL */
214 
215 #endif /* !_FS_DEVFS_DEVFS_H_ */
216