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 <sys/param.h> 38 #include <sys/systm.h> 39 #include <sys/kernel.h> 40 #include <sys/dirent.h> 41 #include <sys/conf.h> 42 #include <sys/proc.h> 43 #include <sys/vnode.h> 44 #include <sys/mount.h> 45 #include <sys/malloc.h> 46 #include <sys/eventhandler.h> 47 48 #define DEVFS_INTERN 49 #include <fs/devfs/devfs.h> 50 51 MALLOC_DEFINE(M_DEVFS, "DEVFS", "DEVFS data"); 52 53 static int devfs_mount __P((struct mount *mp, char *path, caddr_t data, 54 struct nameidata *ndp, struct proc *p)); 55 static int devfs_unmount __P((struct mount *mp, int mntflags, 56 struct proc *p)); 57 static int devfs_root __P((struct mount *mp, struct vnode **vpp)); 58 static int devfs_statfs __P((struct mount *mp, struct statfs *sbp, 59 struct proc *p)); 60 61 /* 62 * Mount the filesystem 63 */ 64 static int 65 devfs_mount(mp, path, data, ndp, p) 66 struct mount *mp; 67 char *path; 68 caddr_t data; 69 struct nameidata *ndp; 70 struct proc *p; 71 { 72 int error = 0; 73 u_int size; 74 struct devfs_mount *fmp; 75 struct vnode *rvp; 76 77 /* 78 * Update is a no-op 79 */ 80 if (mp->mnt_flag & MNT_UPDATE) 81 return (EOPNOTSUPP); 82 83 MALLOC(fmp, struct devfs_mount *, sizeof(struct devfs_mount), M_DEVFS, M_WAITOK); 84 85 bzero(fmp, sizeof(*fmp)); 86 87 error = getnewvnode(VT_DEVFS, mp, devfs_vnodeop_p, &rvp); 88 if (error) { 89 FREE(fmp, M_DEVFS); 90 return (error); 91 } 92 93 vhold(rvp); 94 rvp->v_type = VDIR; 95 rvp->v_flag |= VROOT; 96 mp->mnt_flag |= MNT_LOCAL; 97 mp->mnt_data = (qaddr_t) fmp; 98 vfs_getnewfsid(mp); 99 100 fmp->dm_inode = NDEVINO; 101 fmp->dm_root = rvp; 102 fmp->dm_rootdir = devfs_vmkdir(); 103 rvp->v_data = fmp->dm_rootdir; 104 TAILQ_FIRST(&fmp->dm_rootdir->dd_list)->de_vnode = rvp; 105 TAILQ_FIRST(&fmp->dm_rootdir->dd_list)->de_inode = 2; 106 107 #ifdef DEVFS_DEVBASE 108 { 109 struct devfs_dirent *de; 110 111 fmp->dm_basedir = devfs_vmkdir(); 112 de = devfs_newdirent("dev", 3); 113 de->de_inode = fmp->dm_inode++; 114 de->de_dir = fmp->dm_basedir; 115 TAILQ_FIRST(&de->de_dir->dd_list)->de_inode = de->de_inode; 116 de->de_uid = 0; 117 de->de_gid = 0; 118 de->de_mode = 0755; 119 de->de_dirent->d_type = DT_DIR; 120 TAILQ_INSERT_TAIL(&fmp->dm_rootdir->dd_list, de, de_list); 121 } 122 #else 123 fmp->dm_basedir = fmp->dm_rootdir; 124 #endif 125 126 if (path != NULL) { 127 (void) copyinstr(path, mp->mnt_stat.f_mntonname, MNAMELEN - 1, &size); 128 } else { 129 strcpy(mp->mnt_stat.f_mntonname, "/"); 130 size = 1; 131 } 132 bzero(mp->mnt_stat.f_mntonname + size, MNAMELEN - size); 133 bzero(mp->mnt_stat.f_mntfromname, MNAMELEN); 134 bcopy("devfs", mp->mnt_stat.f_mntfromname, sizeof("devfs")); 135 (void)devfs_statfs(mp, &mp->mnt_stat, p); 136 devfs_populate(fmp); 137 138 return (0); 139 } 140 141 static int 142 devfs_unmount(mp, mntflags, p) 143 struct mount *mp; 144 int mntflags; 145 struct proc *p; 146 { 147 int error; 148 int flags = 0; 149 struct vnode *rootvp = VFSTODEVFS(mp)->dm_root; 150 struct devfs_mount *fmp; 151 152 fmp = (struct devfs_mount*) mp->mnt_data; 153 if (mntflags & MNT_FORCE) 154 flags |= FORCECLOSE; 155 156 /* 157 * Clear out buffer cache. I don't think we 158 * ever get anything cached at this level at the 159 * moment, but who knows... 160 */ 161 if (rootvp->v_usecount > 2) 162 return (EBUSY); 163 devfs_purge(fmp->dm_rootdir); 164 error = vflush(mp, rootvp, flags); 165 if (error) 166 return (error); 167 168 /* 169 * Release reference on underlying root vnode 170 */ 171 vrele(rootvp); 172 /* 173 * And blow it away for future re-use 174 */ 175 vgone(rootvp); 176 /* 177 * Finally, throw away the devfs_mount structure 178 */ 179 free(mp->mnt_data, M_DEVFS); 180 mp->mnt_data = 0; 181 return 0; 182 } 183 184 static int 185 devfs_root(mp, vpp) 186 struct mount *mp; 187 struct vnode **vpp; 188 { 189 struct proc *p = curproc; /* XXX */ 190 struct vnode *vp; 191 192 /* 193 * Return locked reference to root. 194 */ 195 vp = VFSTODEVFS(mp)->dm_root; 196 VREF(vp); 197 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p); 198 *vpp = vp; 199 return (0); 200 } 201 202 static int 203 devfs_statfs(mp, sbp, p) 204 struct mount *mp; 205 struct statfs *sbp; 206 struct proc *p; 207 { 208 209 sbp->f_flags = 0; 210 sbp->f_bsize = DEV_BSIZE; 211 sbp->f_iosize = DEV_BSIZE; 212 sbp->f_blocks = 2; /* 1K to keep df happy */ 213 sbp->f_bfree = 0; 214 sbp->f_bavail = 0; 215 sbp->f_files = 0; 216 sbp->f_ffree = 0; 217 if (sbp != &mp->mnt_stat) { 218 sbp->f_type = mp->mnt_vfc->vfc_typenum; 219 bcopy(&mp->mnt_stat.f_fsid, &sbp->f_fsid, sizeof(sbp->f_fsid)); 220 bcopy(mp->mnt_stat.f_mntonname, sbp->f_mntonname, MNAMELEN); 221 bcopy(mp->mnt_stat.f_mntfromname, sbp->f_mntfromname, MNAMELEN); 222 } 223 return (0); 224 } 225 226 static struct vfsops devfs_vfsops = { 227 devfs_mount, 228 vfs_stdstart, 229 devfs_unmount, 230 devfs_root, 231 vfs_stdquotactl, 232 devfs_statfs, 233 vfs_stdsync, 234 vfs_stdvget, 235 vfs_stdfhtovp, 236 vfs_stdcheckexp, 237 vfs_stdvptofh, 238 vfs_stdinit, 239 vfs_stduninit, 240 vfs_stdextattrctl, 241 }; 242 243 VFS_SET(devfs_vfsops, devfs, VFCF_SYNTHETIC); 244