Return to vfs_hooks.c CVS log | Up to [cvs.NetBSD.org] / src / sys / kern |
File: [cvs.NetBSD.org] / src / sys / kern / vfs_hooks.c (download)
Revision 1.4, Sat May 10 02:26:09 2008 UTC (15 years, 11 months ago) by rumble
Convert file systems to dynamically attach with the new module interface. Make VFS hooks dynamic while we're here and say farewell to VFS_ATTACH and VFS_HOOKS_ATTACH linksets. As a consequence, most of the file systems can now be loaded as new style modules. Quick sanity check by ad@. |
/* $NetBSD: vfs_hooks.c,v 1.4 2008/05/10 02:26:09 rumble Exp $ */ /*- * Copyright (c) 2005 The NetBSD Foundation, Inc. * All rights reserved. * * This code is derived from software contributed to The NetBSD Foundation * by Julio M. Merino Vidal. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. */ /* * VFS hooks. */ #include <sys/cdefs.h> __KERNEL_RCSID(0, "$NetBSD: vfs_hooks.c,v 1.4 2008/05/10 02:26:09 rumble Exp $"); #include <sys/param.h> #include <sys/queue.h> #include <sys/mount.h> #include <sys/mutex.h> LIST_HEAD(vfs_hooks_head, vfs_hooks) vfs_hooks_head = LIST_HEAD_INITIALIZER(vfs_hooks_head); kmutex_t vfs_hooks_lock; void vfs_hooks_init() { mutex_init(&vfs_hooks_lock, MUTEX_DEFAULT, IPL_NONE); } int vfs_hooks_attach(struct vfs_hooks *vfs_hooks) { mutex_enter(&vfs_hooks_lock); LIST_INSERT_HEAD(&vfs_hooks_head, vfs_hooks, vfs_hooks_list); mutex_exit(&vfs_hooks_lock); return (0); } int vfs_hooks_detach(struct vfs_hooks *vfs_hooks) { struct vfs_hooks *hp; int ret = 0; mutex_enter(&vfs_hooks_lock); LIST_FOREACH(hp, &vfs_hooks_head, vfs_hooks_list) { if (hp == vfs_hooks) { LIST_REMOVE(hp, vfs_hooks_list); break; } } if (hp == NULL) ret = ESRCH; mutex_exit(&vfs_hooks_lock); return (ret); } /* * Macro to be used in one of the vfs_hooks_* function for hooks that * return an error code. Calls will stop as soon as one of the hooks * fails. */ #define VFS_HOOKS_W_ERROR(func, fargs, hook, hargs) \ int \ func fargs \ { \ int error; \ struct vfs_hooks *hp; \ \ error = 0; \ \ mutex_enter(&vfs_hooks_lock); \ LIST_FOREACH(hp, &vfs_hooks_head, vfs_hooks_list) { \ if (hp-> hook != NULL) { \ error = hp-> hook args; \ if (error != 0) \ break; \ } \ } \ mutex_exit(&vfs_hooks_lock); \ \ return error; \ } /* * Macro to be used in one of the vfs_hooks_* function for hooks that * do not return any error code. All hooks will be executed * unconditionally. */ #define VFS_HOOKS_WO_ERROR(func, fargs, hook, hargs) \ void \ func fargs \ { \ struct vfs_hooks *hp; \ \ mutex_enter(&vfs_hooks_lock); \ LIST_FOREACH(hp, &vfs_hooks_head, vfs_hooks_list) { \ if (hp-> hook != NULL) \ hp-> hook hargs; \ } \ mutex_exit(&vfs_hooks_lock); \ } /* * Routines to iterate over VFS hooks lists and execute them. */ VFS_HOOKS_WO_ERROR(vfs_hooks_unmount, (struct mount *mp), vh_unmount, (mp));