xref: /netbsd/sys/miscfs/specfs/specdev.h (revision 22241105)
1 /*	$NetBSD: specdev.h,v 1.54 2023/04/22 14:30:16 hannken Exp $	*/
2 
3 /*-
4  * Copyright (c) 2008 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
17  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
18  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
19  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
20  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26  * POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 /*
30  * Copyright (c) 1990, 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. Neither the name of the University nor the names of its contributors
42  *    may be used to endorse or promote products derived from this software
43  *    without specific prior written permission.
44  *
45  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
46  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
47  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
48  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
49  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
50  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
51  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
52  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
53  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
54  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
55  * SUCH DAMAGE.
56  *
57  *	@(#)specdev.h	8.6 (Berkeley) 5/21/95
58  */
59 
60 #ifndef _MISCFS_SPECFS_SPECDEV_H_
61 #define _MISCFS_SPECFS_SPECDEV_H_
62 
63 #include <sys/mutex.h>
64 #include <sys/vnode.h>
65 
66 typedef struct specnode {
67 	vnode_t		*sn_next;
68 	struct specdev	*sn_dev;
69 	dev_t		sn_rdev;
70 	u_int		sn_opencnt;	/* # of opens, share of sd_opencnt */
71 	bool		sn_gone;
72 } specnode_t;
73 
74 typedef struct specdev {
75 	struct mount	*sd_mountpoint;
76 	struct lockf	*sd_lockf;
77 	vnode_t		*sd_bdevvp;
78 	u_int		sd_opencnt;	/* # of opens; close when ->0 */
79 	u_int		sd_refcnt;	/* # of specnodes referencing this */
80 	volatile u_int	sd_iocnt;	/* # bdev/cdev_* operations active */
81 	bool		sd_opened;	/* true if successfully opened */
82 	bool		sd_closing;	/* true when bdev/cdev_close ongoing */
83 } specdev_t;
84 
85 /*
86  * Exported shorthand
87  */
88 #define v_specnext	v_specnode->sn_next
89 #define v_rdev		v_specnode->sn_rdev
90 #define v_speclockf	v_specnode->sn_dev->sd_lockf
91 
92 /*
93  * Special device management
94  */
95 void	spec_node_init(vnode_t *, dev_t);
96 void	spec_node_destroy(vnode_t *);
97 int	spec_node_lookup_by_dev(enum vtype, dev_t, int, vnode_t **);
98 int	spec_node_lookup_by_mount(struct mount *, vnode_t **);
99 struct mount *spec_node_getmountedfs(vnode_t *);
100 void	spec_node_setmountedfs(vnode_t *, struct mount *);
101 void	spec_node_revoke(vnode_t *);
102 
103 /*
104  * Prototypes for special file operations on vnodes.
105  */
106 extern const struct vnodeopv_desc spec_vnodeop_opv_desc;
107 extern	int (**spec_vnodeop_p)(void *);
108 struct	nameidata;
109 struct	componentname;
110 struct	flock;
111 struct	buf;
112 struct	uio;
113 
114 int	spec_lookup(void *);
115 int	spec_open(void *);
116 int	spec_close(void *);
117 int	spec_read(void *);
118 int	spec_write(void *);
119 int	spec_fdiscard(void *);
120 int	spec_ioctl(void *);
121 int	spec_poll(void *);
122 int	spec_kqfilter(void *);
123 int	spec_mmap(void *);
124 int	spec_fsync(void *);
125 #define	spec_seek	genfs_nullop		/* XXX should query device */
126 int	spec_inactive(void *);
127 int	spec_reclaim(void *);
128 int	spec_bmap(void *);
129 int	spec_strategy(void *);
130 int	spec_print(void *);
131 int	spec_pathconf(void *);
132 int	spec_advlock(void *);
133 
134 /*
135  * This macro provides an initializer list for the fs-independent part
136  * of a filesystem's special file vnode ops descriptor table. We still
137  * need such a table in every filesystem, but we can at least avoid
138  * the cutpaste.
139  *
140  * This contains these ops:
141  *    parsepath lookup
142  *    create whiteout mknod open fallocate fdiscard ioctl poll kqfilter
143  *    revoke mmap seek remove link rename mkdir rmdir symlink readdir
144  *    readlink abortop bmap strategy pathconf advlock getpages putpages
145  *
146  * The filesystem should provide these ops that need to be its own:
147  *    access and accessx
148  *    getattr
149  *    setattr
150  *    fcntl
151  *    inactive
152  *    reclaim
153  *    lock
154  *    unlock
155  *    print (should probably also call spec_print)
156  *    islocked
157  *    bwrite (normally vn_bwrite)
158  *    openextattr
159  *    closeextattr
160  *    getextattr
161  *    setextattr
162  *    listextattr
163  *    deleteextattr
164  *    getacl
165  *    setacl
166  *    aclcheck
167  *
168  * The filesystem should also provide these ops that some filesystems
169  * do their own things with:
170  *    close
171  *    read
172  *    write
173  *    fsync
174  * In most cases "their own things" means adjust timestamps and call
175  * spec_foo. For fsync it varies, but should always also call spec_fsync.
176  *
177  * Note that because the op descriptor tables are unordered it does not
178  * matter where in the table this macro goes (except I think default
179  * still needs to be first...)
180  */
181 #define GENFS_SPECOP_ENTRIES \
182 	{ &vop_parsepath_desc, genfs_badop },		/* parsepath */	\
183 	{ &vop_lookup_desc, spec_lookup },		/* lookup */	\
184 	{ &vop_create_desc, genfs_badop },		/* create */	\
185 	{ &vop_whiteout_desc, genfs_badop },		/* whiteout */	\
186 	{ &vop_mknod_desc, genfs_badop },		/* mknod */	\
187 	{ &vop_open_desc, spec_open },			/* open */	\
188 	{ &vop_fallocate_desc, genfs_eopnotsupp },	/* fallocate */	\
189 	{ &vop_fdiscard_desc, spec_fdiscard },		/* fdiscard */	\
190 	{ &vop_ioctl_desc, spec_ioctl },		/* ioctl */	\
191 	{ &vop_poll_desc, spec_poll },			/* poll */	\
192 	{ &vop_kqfilter_desc, spec_kqfilter },		/* kqfilter */	\
193 	{ &vop_revoke_desc, genfs_revoke },		/* revoke */	\
194 	{ &vop_mmap_desc, spec_mmap },			/* mmap */	\
195 	{ &vop_seek_desc, spec_seek },			/* seek */	\
196 	{ &vop_remove_desc, genfs_badop },		/* remove */	\
197 	{ &vop_link_desc, genfs_badop },		/* link */	\
198 	{ &vop_rename_desc, genfs_badop },		/* rename */	\
199 	{ &vop_mkdir_desc, genfs_badop },		/* mkdir */	\
200 	{ &vop_rmdir_desc, genfs_badop },		/* rmdir */	\
201 	{ &vop_symlink_desc, genfs_badop },		/* symlink */	\
202 	{ &vop_readdir_desc, genfs_badop },		/* readdir */	\
203 	{ &vop_readlink_desc, genfs_badop },		/* readlink */	\
204 	{ &vop_abortop_desc, genfs_badop },		/* abortop */	\
205 	{ &vop_bmap_desc, spec_bmap },			/* bmap */	\
206 	{ &vop_strategy_desc, spec_strategy },		/* strategy */	\
207 	{ &vop_pathconf_desc, spec_pathconf },		/* pathconf */	\
208 	{ &vop_advlock_desc, spec_advlock },		/* advlock */	\
209 	{ &vop_getpages_desc, genfs_getpages },		/* getpages */	\
210 	{ &vop_putpages_desc, genfs_putpages }		/* putpages */
211 
212 
213 bool	iskmemvp(struct vnode *);
214 void	spec_init(void);
215 
216 #endif /* _MISCFS_SPECFS_SPECDEV_H_ */
217