1/* $NetBSD: kernfs.h,v 1.45 2025/06/27 21:36:25 andvar Exp $ */
2
3/*
4 * Copyright (c) 1992, 1993
5 * The Regents of the University of California. All rights reserved.
6 *
7 * This code is derived from software donated to Berkeley by
8 * Jan-Simon Pendry.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. Neither the name of the University nor the names of its contributors
19 * may be used to endorse or promote products derived from this software
20 * without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 *
34 * @(#)kernfs.h 8.6 (Berkeley) 3/29/95
35 */
36
37#define _PATH_KERNFS "/kern" /* Default mountpoint */
38
39#ifdef _KERNEL
40#include <sys/queue.h>
41#include <sys/tree.h>
42#include <sys/mutex.h>
43
44/*
45 * The different types of node in a kernfs filesystem
46 */
47typedef enum {
48 KFSkern, /* the filesystem itself (.) */
49 KFSroot, /* the filesystem root (..) */
50 KFSnull, /* none applicable */
51 KFStime, /* time */
52 KFSboottime, /* boottime */
53 KFSint, /* integer */
54 KFSstring, /* string */
55 KFShostname, /* hostname */
56 KFSavenrun, /* loadavg */
57 KFSdevice, /* device file (rootdev/rrootdev) */
58 KFSmsgbuf, /* msgbuf */
59 KFSsubdir, /* directory */
60 KFSlasttype, /* last used type */
61 KFSmaxtype = (1<<6) - 1 /* last possible type */
62} kfstype;
63
64/*
65 * Control data for the kern file system.
66 */
67struct kern_target {
68 u_char kt_type;
69 u_char kt_namlen;
70 const char *kt_name;
71 void *kt_data;
72 kfstype kt_tag;
73 u_char kt_vtype;
74 mode_t kt_mode;
75};
76
77struct dyn_kern_target {
78 struct kern_target dkt_kt;
79 SIMPLEQ_ENTRY(dyn_kern_target) dkt_queue;
80};
81
82struct kernfs_subdir {
83 SIMPLEQ_HEAD(,dyn_kern_target) ks_entries;
84 unsigned int ks_nentries;
85 unsigned int ks_dirs;
86 const struct kern_target *ks_parent;
87};
88
89struct kernfs_node {
90 LIST_ENTRY(kernfs_node) kfs_hash; /* hash chain */
91 TAILQ_ENTRY(kernfs_node) kfs_list; /* flat list */
92 struct vnode *kfs_vnode; /* vnode associated with this kernfs_node */
93 kfstype kfs_type; /* type of kernfs node */
94 mode_t kfs_mode; /* mode bits for stat() */
95 long kfs_fileno; /* unique file id */
96 const struct kern_target *kfs_kt;
97 void *kfs_v; /* dynamic node private data */
98 long kfs_cookie; /* fileno cookie */
99};
100
101struct kernfs_mount {
102 TAILQ_HEAD(, kernfs_node) nodelist;
103 long fileno_cookie;
104};
105
106#define UIO_MX 32
107
108#define KERNFS_FILENO(kt, typ, cookie) \
109 ((kt >= &kern_targets[0] && kt < &kern_targets[static_nkern_targets]) \
110 ? 2 + ((kt) - &kern_targets[0]) \
111 : (((cookie + 1) << 6) | (typ)))
112#define KERNFS_TYPE_FILENO(typ, cookie) \
113 (((cookie + 1) << 6) | (typ))
114
115#define VFSTOKERNFS(mp) ((struct kernfs_mount *)((mp)->mnt_data))
116#define VTOKERN(vp) ((struct kernfs_node *)(vp)->v_data)
117#define KERNFSTOV(kfs) ((kfs)->kfs_vnode)
118
119#define KERNFS_MAXNAMLEN 255
120
121extern const struct kern_target kern_targets[];
122extern int nkern_targets;
123extern const int static_nkern_targets;
124extern int (**kernfs_vnodeop_p)(void *);
125extern int (**kernfs_specop_p)(void *);
126extern struct vfsops kernfs_vfsops;
127extern dev_t rrootdev;
128extern kmutex_t kfs_lock;
129
130int kernfs_root(struct mount *, int, struct vnode **);
131
132/*
133 * Data types for the kernfs file operations.
134 */
135typedef enum {
136 KERNFS_XREAD,
137 KERNFS_XWRITE,
138 KERNFS_FILEOP_CLOSE,
139 KERNFS_FILEOP_GETATTR,
140 KERNFS_FILEOP_IOCTL,
141 KERNFS_FILEOP_OPEN,
142 KERNFS_FILEOP_READ,
143 KERNFS_FILEOP_WRITE,
144} kfsfileop;
145
146struct kernfs_fileop {
147 kfstype kf_type;
148 kfsfileop kf_fileop;
149 union {
150 int (*_kf_vop)(void *);
151 int (*_kf_xread)
152 (const struct kernfs_node *, char **, size_t);
153 int (*_kf_xwrite)
154 (const struct kernfs_node *, char *, size_t);
155 } _kf_opfn;
156 SPLAY_ENTRY(kernfs_fileop) kf_node;
157};
158
159#define kf_vop _kf_opfn._kf_vop
160#define kf_xread _kf_opfn._kf_xread
161#define kf_xwrite _kf_opfn._kf_xwrite
162
163typedef struct kern_target kernfs_parentdir_t;
164typedef struct dyn_kern_target kernfs_entry_t;
165
166/*
167 * Functions for adding kernfs datatypes and nodes.
168 */
169kfstype kernfs_alloctype(int, const struct kernfs_fileop *);
170#define KERNFS_ALLOCTYPE(kf) kernfs_alloctype(sizeof((kf)) / \
171 sizeof((kf)[0]), (kf))
172#define KERNFS_ALLOCENTRY(dkt, km_flags) \
173 dkt = (kernfs_entry_t *)kmem_zalloc( \
174 sizeof(struct dyn_kern_target), (km_flags))
175#define KERNFS_INITENTRY(dkt, type, name, data, tag, vtype, mode) do { \
176 (dkt)->dkt_kt.kt_type = (type); \
177 (dkt)->dkt_kt.kt_namlen = strlen((name)); \
178 (dkt)->dkt_kt.kt_name = (name); \
179 (dkt)->dkt_kt.kt_data = (data); \
180 (dkt)->dkt_kt.kt_tag = (tag); \
181 (dkt)->dkt_kt.kt_vtype = (vtype); \
182 (dkt)->dkt_kt.kt_mode = (mode); \
183} while (/*CONSTCOND*/0)
184#define KERNFS_ENTOPARENTDIR(dkt) &(dkt)->dkt_kt
185int kernfs_addentry(kernfs_parentdir_t *, kernfs_entry_t *);
186
187#ifdef IPSEC
188__weak_extern(key_freesp)
189__weak_extern(key_getspbyid)
190__weak_extern(key_setdumpsa_spi)
191__weak_extern(key_setdumpsp)
192__weak_extern(satailq)
193__weak_extern(sptailq)
194#endif
195
196#endif /* _KERNEL */