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