FreeBSD/Linux Kernel Cross Reference
sys/kern/vfs_hooks.c
1 /* $NetBSD: vfs_hooks.c,v 1.2 2005/12/11 12:24:30 christos Exp $ */
2
3 /*-
4 * Copyright (c) 2005 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Julio M. Merino Vidal.
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. All advertising materials mentioning features or use of this software
19 * must display the following acknowledgement:
20 * This product includes software developed by the NetBSD
21 * Foundation, Inc. and its contributors.
22 * 4. Neither the name of The NetBSD Foundation nor the names of its
23 * contributors may be used to endorse or promote products derived
24 * from this software without specific prior written permission.
25 *
26 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36 * POSSIBILITY OF SUCH DAMAGE.
37 */
38
39 /*
40 * VFS hooks.
41 */
42
43 #include <sys/cdefs.h>
44 __KERNEL_RCSID(0, "$NetBSD: vfs_hooks.c,v 1.2 2005/12/11 12:24:30 christos Exp $");
45
46 #include <sys/param.h>
47 #include <sys/mount.h>
48
49 /*
50 * Static list of file system specific hook sets supported by the kernel.
51 */
52 __link_set_decl(vfs_hooks, struct vfs_hooks);
53
54 /*
55 * Initialize a VFS hook set that does nothing. This is to ensure that
56 * we have, at the very least, one item in the link set. Otherwise,
57 * ld(1) will complain.
58 */
59 static struct vfs_hooks null_hooks = {
60 NULL /* vh_unmount */
61 };
62 VFS_HOOKS_ATTACH(null_hooks);
63
64 /*
65 * Macro to be used in one of the vfs_hooks_* function for hooks that
66 * return an error code. Calls will stop as soon as one of the hooks
67 * fails.
68 */
69 #define VFS_HOOKS_W_ERROR(func, args) \
70 int error; \
71 struct vfs_hooks * const *hp; \
72 \
73 error = 0; \
74 \
75 __link_set_foreach(hp, vfs_hooks) { \
76 if ((*hp)-> func != NULL) { \
77 error = (*hp)-> func args; \
78 if (error != 0) \
79 break; \
80 } \
81 } \
82 \
83 return error;
84
85 /*
86 * Macro to be used in one of the vfs_hooks_* function for hooks that
87 * do not return any error code. All hooks will be executed
88 * unconditionally.
89 */
90 #define VFS_HOOKS_WO_ERROR(func, fargs, hook, hargs) \
91 void \
92 func fargs \
93 { \
94 struct vfs_hooks * const *hp; \
95 \
96 __link_set_foreach(hp, vfs_hooks) { \
97 if ((*hp)-> hook != NULL) \
98 (*hp)-> hook hargs; \
99 } \
100 }
101
102 /*
103 * Routines to iterate over VFS hooks lists and execute them.
104 */
105
106 VFS_HOOKS_WO_ERROR(vfs_hooks_unmount, (struct mount *mp), vh_unmount, (mp));
107
108 /*
109 void
110 vfs_hooks_unmount(struct mount *mp)
111 {
112
113 VFS_HOOKS_WO_ERROR(vh_unmount, (mp));
114 }
115 */
Cache object: 535c99ebf41071ca2bc7fb75d6320bb3
|