1 /*- 2 * Copyright (c) 1992, 1993, 1995 3 * The Regents of the University of California. All rights reserved. 4 * Copyright (c) 2000 5 * Poul-Henning Kamp. 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. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 * 31 * @(#)kernfs_vfsops.c 8.10 (Berkeley) 5/14/95 32 * From: FreeBSD: src/sys/miscfs/kernfs/kernfs_vfsops.c 1.36 33 * 34 * $FreeBSD$ 35 */ 36 37 #include "opt_devfs.h" 38 #include "opt_mac.h" 39 40 #include <sys/param.h> 41 #include <sys/systm.h> 42 #include <sys/kernel.h> 43 #include <sys/lock.h> 44 #include <sys/mac.h> 45 #include <sys/malloc.h> 46 #include <sys/mount.h> 47 #include <sys/proc.h> 48 #include <sys/sx.h> 49 #include <sys/vnode.h> 50 #include <sys/limits.h> 51 52 #include <fs/devfs/devfs.h> 53 54 static struct unrhdr *devfs_unr; 55 56 MALLOC_DEFINE(M_DEVFS, "DEVFS", "DEVFS data"); 57 58 static vfs_mount_t devfs_mount; 59 static vfs_unmount_t devfs_unmount; 60 static vfs_root_t devfs_root; 61 static vfs_statfs_t devfs_statfs; 62 63 /* 64 * Mount the filesystem 65 */ 66 static int 67 devfs_mount(struct mount *mp, struct thread *td) 68 { 69 int error; 70 struct devfs_mount *fmp; 71 struct vnode *rvp; 72 73 if (devfs_unr == NULL) 74 devfs_unr = new_unrhdr(0, INT_MAX, NULL); 75 76 error = 0; 77 78 if (mp->mnt_flag & (MNT_UPDATE | MNT_ROOTFS)) 79 return (EOPNOTSUPP); 80 81 fmp = malloc(sizeof *fmp, M_DEVFS, M_WAITOK | M_ZERO); 82 fmp->dm_idx = alloc_unr(devfs_unr); 83 sx_init(&fmp->dm_lock, "devfsmount"); 84 85 mp->mnt_flag |= MNT_LOCAL; 86 mp->mnt_kern_flag |= MNTK_MPSAFE; 87 #ifdef MAC 88 mp->mnt_flag |= MNT_MULTILABEL; 89 #endif 90 fmp->dm_mount = mp; 91 mp->mnt_data = (void *) fmp; 92 vfs_getnewfsid(mp); 93 94 fmp->dm_rootdir = devfs_vmkdir(fmp, NULL, 0, NULL, DEVFS_ROOTINO); 95 96 error = devfs_root(mp, LK_EXCLUSIVE, &rvp, td); 97 if (error) { 98 sx_destroy(&fmp->dm_lock); 99 free_unr(devfs_unr, fmp->dm_idx); 100 free(fmp, M_DEVFS); 101 return (error); 102 } 103 104 VOP_UNLOCK(rvp, 0, td); 105 106 vfs_mountedfrom(mp, "devfs"); 107 108 return (0); 109 } 110 111 static int 112 devfs_unmount(struct mount *mp, int mntflags, struct thread *td) 113 { 114 int error; 115 int flags = 0; 116 struct devfs_mount *fmp; 117 118 fmp = VFSTODEVFS(mp); 119 /* There is 1 extra root vnode reference from devfs_mount(). */ 120 error = vflush(mp, 1, flags, td); 121 if (error) 122 return (error); 123 sx_xlock(&fmp->dm_lock); 124 devfs_cleanup(fmp); 125 devfs_rules_cleanup(fmp); 126 sx_xunlock(&fmp->dm_lock); 127 mp->mnt_data = NULL; 128 sx_destroy(&fmp->dm_lock); 129 free_unr(devfs_unr, fmp->dm_idx); 130 free(fmp, M_DEVFS); 131 return 0; 132 } 133 134 /* Return locked reference to root. */ 135 136 static int 137 devfs_root(struct mount *mp, int flags, struct vnode **vpp, struct thread *td) 138 { 139 int error; 140 struct vnode *vp; 141 struct devfs_mount *dmp; 142 143 dmp = VFSTODEVFS(mp); 144 error = devfs_allocv(dmp->dm_rootdir, mp, &vp, td); 145 if (error) 146 return (error); 147 vp->v_vflag |= VV_ROOT; 148 *vpp = vp; 149 return (0); 150 } 151 152 static int 153 devfs_statfs(struct mount *mp, struct statfs *sbp, struct thread *td) 154 { 155 156 sbp->f_flags = 0; 157 sbp->f_bsize = DEV_BSIZE; 158 sbp->f_iosize = DEV_BSIZE; 159 sbp->f_blocks = 2; /* 1K to keep df happy */ 160 sbp->f_bfree = 0; 161 sbp->f_bavail = 0; 162 sbp->f_files = 0; 163 sbp->f_ffree = 0; 164 return (0); 165 } 166 167 static struct vfsops devfs_vfsops = { 168 .vfs_mount = devfs_mount, 169 .vfs_root = devfs_root, 170 .vfs_statfs = devfs_statfs, 171 .vfs_unmount = devfs_unmount, 172 }; 173 174 VFS_SET(devfs_vfsops, devfs, VFCF_SYNTHETIC); 175