1 /* $NetBSD: layer_vfsops.c,v 1.19 2004/05/29 23:48:08 wrstuden Exp $ */ 2 3 /* 4 * Copyright (c) 1999 National Aeronautics & Space Administration 5 * All rights reserved. 6 * 7 * This software was written by William Studenmund of the 8 * Numerical Aerospace Simulation Facility, NASA Ames Research Center. 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 National Aeronautics & Space Administration 19 * nor the names of its contributors may be used to endorse or promote 20 * products derived from this software without specific prior written 21 * permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE NATIONAL AERONAUTICS & SPACE ADMINISTRATION 24 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 25 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 26 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE ADMINISTRATION OR CONTRIB- 27 * UTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, 28 * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 29 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 30 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 31 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 32 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 33 * POSSIBILITY OF SUCH DAMAGE. 34 */ 35 /* 36 * Copyright (c) 1992, 1993, 1995 37 * The Regents of the University of California. All rights reserved. 38 * 39 * This code is derived from software donated to Berkeley by 40 * Jan-Simon Pendry. 41 * 42 * Redistribution and use in source and binary forms, with or without 43 * modification, are permitted provided that the following conditions 44 * are met: 45 * 1. Redistributions of source code must retain the above copyright 46 * notice, this list of conditions and the following disclaimer. 47 * 2. Redistributions in binary form must reproduce the above copyright 48 * notice, this list of conditions and the following disclaimer in the 49 * documentation and/or other materials provided with the distribution. 50 * 3. Neither the name of the University nor the names of its contributors 51 * may be used to endorse or promote products derived from this software 52 * without specific prior written permission. 53 * 54 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 55 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 56 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 57 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 58 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 59 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 60 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 61 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 62 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 63 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 64 * SUCH DAMAGE. 65 * 66 * from: Id: lofs_vfsops.c,v 1.9 1992/05/30 10:26:24 jsp Exp 67 * from: @(#)lofs_vfsops.c 1.2 (Berkeley) 6/18/92 68 * @(#)null_vfsops.c 8.7 (Berkeley) 5/14/95 69 */ 70 71 /* 72 * generic layer vfs ops. 73 */ 74 75 #include <sys/cdefs.h> 76 __KERNEL_RCSID(0, "$NetBSD: layer_vfsops.c,v 1.19 2004/05/29 23:48:08 wrstuden Exp $"); 77 78 #include <sys/param.h> 79 #include <sys/sysctl.h> 80 #include <sys/systm.h> 81 #include <sys/time.h> 82 #include <sys/proc.h> 83 #include <sys/vnode.h> 84 #include <sys/mount.h> 85 #include <sys/namei.h> 86 #include <sys/malloc.h> 87 #include <miscfs/genfs/layer.h> 88 #include <miscfs/genfs/layer_extern.h> 89 90 /* 91 * VFS start. Nothing needed here - the start routine 92 * on the underlying filesystem will have been called 93 * when that filesystem was mounted. 94 */ 95 int 96 layerfs_start(mp, flags, p) 97 struct mount *mp; 98 int flags; 99 struct proc *p; 100 { 101 102 return (0); 103 /* return VFS_START(MOUNTTOLAYERMOUNT(mp)->layerm_vfs, flags, p); */ 104 } 105 106 int 107 layerfs_root(mp, vpp) 108 struct mount *mp; 109 struct vnode **vpp; 110 { 111 struct vnode *vp; 112 113 #ifdef LAYERFS_DIAGNOSTIC 114 printf("layerfs_root(mp = %p, vp = %p->%p)\n", mp, 115 MOUNTTOLAYERMOUNT(mp)->layerm_rootvp, 116 LAYERVPTOLOWERVP(MOUNTTOLAYERMOUNT(mp)->layerm_rootvp)); 117 #endif 118 119 /* 120 * Return locked reference to root. 121 */ 122 vp = MOUNTTOLAYERMOUNT(mp)->layerm_rootvp; 123 if (vp == NULL) { 124 *vpp = NULL; 125 return (EINVAL); 126 } 127 VREF(vp); 128 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 129 *vpp = vp; 130 return 0; 131 } 132 133 int 134 layerfs_quotactl(mp, cmd, uid, arg, p) 135 struct mount *mp; 136 int cmd; 137 uid_t uid; 138 void *arg; 139 struct proc *p; 140 { 141 142 return VFS_QUOTACTL(MOUNTTOLAYERMOUNT(mp)->layerm_vfs, 143 cmd, uid, arg, p); 144 } 145 146 int 147 layerfs_statvfs(mp, sbp, p) 148 struct mount *mp; 149 struct statvfs *sbp; 150 struct proc *p; 151 { 152 int error; 153 struct statvfs *sbuf = malloc(sizeof(*sbuf), M_TEMP, M_WAITOK); 154 155 #ifdef LAYERFS_DIAGNOSTIC 156 printf("layerfs_statvfs(mp = %p, vp = %p->%p)\n", mp, 157 MOUNTTOLAYERMOUNT(mp)->layerm_rootvp, 158 LAYERVPTOLOWERVP(MOUNTTOLAYERMOUNT(mp)->layerm_rootvp)); 159 #endif 160 161 (void)memset(sbuf, 0, sizeof(*sbuf)); 162 163 error = VFS_STATVFS(MOUNTTOLAYERMOUNT(mp)->layerm_vfs, sbuf, p); 164 if (error) 165 goto done; 166 167 /* now copy across the "interesting" information and fake the rest */ 168 sbp->f_flag = sbuf->f_flag; 169 sbp->f_bsize = sbuf->f_bsize; 170 sbp->f_frsize = sbuf->f_frsize; 171 sbp->f_iosize = sbuf->f_iosize; 172 sbp->f_blocks = sbuf->f_blocks; 173 sbp->f_bfree = sbuf->f_bfree; 174 sbp->f_bavail = sbuf->f_bavail; 175 sbp->f_bresvd = sbuf->f_bresvd; 176 sbp->f_files = sbuf->f_files; 177 sbp->f_ffree = sbuf->f_ffree; 178 sbp->f_favail = sbuf->f_favail; 179 sbp->f_fresvd = sbuf->f_fresvd; 180 sbp->f_namemax = sbuf->f_namemax; 181 copy_statvfs_info(sbp, mp); 182 done: 183 free(sbuf, M_TEMP); 184 return error; 185 } 186 187 int 188 layerfs_sync(mp, waitfor, cred, p) 189 struct mount *mp; 190 int waitfor; 191 struct ucred *cred; 192 struct proc *p; 193 { 194 195 /* 196 * XXX - Assumes no data cached at layer. 197 */ 198 return (0); 199 } 200 201 int 202 layerfs_vget(mp, ino, vpp) 203 struct mount *mp; 204 ino_t ino; 205 struct vnode **vpp; 206 { 207 int error; 208 struct vnode *vp; 209 210 if ((error = VFS_VGET(MOUNTTOLAYERMOUNT(mp)->layerm_vfs, ino, &vp))) { 211 *vpp = NULL; 212 return (error); 213 } 214 if ((error = layer_node_create(mp, vp, vpp))) { 215 vput(vp); 216 *vpp = NULL; 217 return (error); 218 } 219 220 return (0); 221 } 222 223 int 224 layerfs_fhtovp(mp, fidp, vpp) 225 struct mount *mp; 226 struct fid *fidp; 227 struct vnode **vpp; 228 { 229 int error; 230 struct vnode *vp; 231 232 if ((error = VFS_FHTOVP(MOUNTTOLAYERMOUNT(mp)->layerm_vfs, fidp, &vp))) 233 return (error); 234 235 if ((error = layer_node_create(mp, vp, vpp))) { 236 vput(vp); 237 *vpp = NULL; 238 return (error); 239 } 240 241 return (0); 242 } 243 244 int 245 layerfs_checkexp(mp, nam, exflagsp, credanonp) 246 struct mount *mp; 247 struct mbuf *nam; 248 int *exflagsp; 249 struct ucred**credanonp; 250 { 251 struct netcred *np; 252 struct layer_mount *lmp = MOUNTTOLAYERMOUNT(mp); 253 254 /* 255 * get the export permission structure for this <mp, client> tuple. 256 */ 257 if ((np = vfs_export_lookup(mp, &lmp->layerm_export, nam)) == NULL) 258 return (EACCES); 259 260 *exflagsp = np->netc_exflags; 261 *credanonp = &np->netc_anon; 262 return (0); 263 } 264 265 int 266 layerfs_vptofh(vp, fhp) 267 struct vnode *vp; 268 struct fid *fhp; 269 { 270 271 return (VFS_VPTOFH(LAYERVPTOLOWERVP(vp), fhp)); 272 } 273 274 /* 275 * layerfs_snapshot - handle a snapshot through a layered file system 276 * 277 * At present, we do NOT support snapshotting through a layered file 278 * system as the ffs implementation changes v_vnlock of the snapshot 279 * vnodes to point to one common lock. As there is no way for us to 280 * absolutely pass this change up the stack, a layered file system 281 * would end up referencing the wrong lock. 282 * 283 * This routine serves as a central resource for this behavior; all 284 * layered file systems don't need to worry about the above. Also, if 285 * things get fixed, all layers get the benefit. 286 */ 287 int 288 layerfs_snapshot(struct mount *mp, struct vnode *vp, struct timespec *ts) 289 { 290 return (EOPNOTSUPP); 291 } 292 293 SYSCTL_SETUP(sysctl_vfs_layerfs_setup, "sysctl vfs.layerfs subtree setup") 294 { 295 296 sysctl_createv(clog, 0, NULL, NULL, 297 CTLFLAG_PERMANENT, 298 CTLTYPE_NODE, "vfs", NULL, 299 NULL, 0, NULL, 0, 300 CTL_VFS, CTL_EOL); 301 sysctl_createv(clog, 0, NULL, NULL, 302 CTLFLAG_PERMANENT, 303 CTLTYPE_NODE, "layerfs", 304 SYSCTL_DESCR("Generic layered file system"), 305 NULL, 0, NULL, 0, 306 CTL_VFS, CTL_CREATE); 307 /* 308 * other subtrees should really be aliases to this, but since 309 * they can't tell if layerfs has been instantiated yet, they 310 * can't do that...not easily. not yet. :-) 311 */ 312 } 313