1 /* $NetBSD: umap_vfsops.c,v 1.49 2004/07/01 10:03:32 hannken Exp $ */ 2 3 /* 4 * Copyright (c) 1992, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software donated to Berkeley by 8 * the UCLA Ficus project. 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 University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * from: @(#)null_vfsops.c 1.5 (Berkeley) 7/10/92 35 * @(#)umap_vfsops.c 8.8 (Berkeley) 5/14/95 36 */ 37 38 /* 39 * Umap Layer 40 * (See mount_umap(8) for a description of this layer.) 41 */ 42 43 #include <sys/cdefs.h> 44 __KERNEL_RCSID(0, "$NetBSD: umap_vfsops.c,v 1.49 2004/07/01 10:03:32 hannken Exp $"); 45 46 #include <sys/param.h> 47 #include <sys/systm.h> 48 #include <sys/sysctl.h> 49 #include <sys/proc.h> 50 #include <sys/time.h> 51 #include <sys/vnode.h> 52 #include <sys/mount.h> 53 #include <sys/namei.h> 54 #include <sys/malloc.h> 55 #include <miscfs/umapfs/umap.h> 56 #include <miscfs/genfs/layer_extern.h> 57 58 int umapfs_mount __P((struct mount *, const char *, void *, 59 struct nameidata *, struct proc *)); 60 int umapfs_unmount __P((struct mount *, int, struct proc *)); 61 62 /* 63 * Mount umap layer 64 */ 65 int 66 umapfs_mount(mp, path, data, ndp, p) 67 struct mount *mp; 68 const char *path; 69 void *data; 70 struct nameidata *ndp; 71 struct proc *p; 72 { 73 struct umap_args args; 74 struct vnode *lowerrootvp, *vp; 75 struct umap_mount *amp; 76 int error; 77 #ifdef UMAPFS_DIAGNOSTIC 78 int i; 79 #endif 80 if (mp->mnt_flag & MNT_GETARGS) { 81 amp = MOUNTTOUMAPMOUNT(mp); 82 if (amp == NULL) 83 return EIO; 84 args.la.target = NULL; 85 vfs_showexport(mp, &args.la.export, &->umapm_export); 86 args.nentries = amp->info_nentries; 87 args.gnentries = amp->info_gnentries; 88 return copyout(&args, data, sizeof(args)); 89 } 90 91 /* only for root */ 92 if ((error = suser(p->p_ucred, &p->p_acflag)) != 0) 93 return error; 94 95 #ifdef UMAPFS_DIAGNOSTIC 96 printf("umapfs_mount(mp = %p)\n", mp); 97 #endif 98 99 /* 100 * Get argument 101 */ 102 error = copyin(data, &args, sizeof(struct umap_args)); 103 if (error) 104 return (error); 105 106 /* 107 * Update only does export updating. 108 */ 109 if (mp->mnt_flag & MNT_UPDATE) { 110 amp = MOUNTTOUMAPMOUNT(mp); 111 if (args.umap_target == 0) 112 return (vfs_export(mp, &->umapm_export, 113 &args.umap_export)); 114 else 115 return (EOPNOTSUPP); 116 } 117 118 /* 119 * Find lower node 120 */ 121 NDINIT(ndp, LOOKUP, FOLLOW|LOCKLEAF, 122 UIO_USERSPACE, args.umap_target, p); 123 if ((error = namei(ndp)) != 0) 124 return (error); 125 126 /* 127 * Sanity check on lower vnode 128 */ 129 lowerrootvp = ndp->ni_vp; 130 #ifdef UMAPFS_DIAGNOSTIC 131 printf("vp = %p, check for VDIR...\n", lowerrootvp); 132 #endif 133 134 if (lowerrootvp->v_type != VDIR) { 135 vput(lowerrootvp); 136 return (EINVAL); 137 } 138 139 #ifdef UMAPFS_DIAGNOSTIC 140 printf("mp = %p\n", mp); 141 #endif 142 143 amp = (struct umap_mount *) malloc(sizeof(struct umap_mount), 144 M_UFSMNT, M_WAITOK); /* XXX */ 145 memset(amp, 0, sizeof(struct umap_mount)); 146 147 mp->mnt_data = amp; 148 mp->mnt_leaf = lowerrootvp->v_mount->mnt_leaf; 149 amp->umapm_vfs = lowerrootvp->v_mount; 150 if (amp->umapm_vfs->mnt_flag & MNT_LOCAL) 151 mp->mnt_flag |= MNT_LOCAL; 152 153 /* 154 * Now copy in the number of entries and maps for umap mapping. 155 */ 156 if (args.nentries > MAPFILEENTRIES || args.gnentries > GMAPFILEENTRIES) { 157 vput(lowerrootvp); 158 return (error); 159 } 160 161 amp->info_nentries = args.nentries; 162 amp->info_gnentries = args.gnentries; 163 error = copyin(args.mapdata, amp->info_mapdata, 164 2*sizeof(u_long)*args.nentries); 165 if (error) { 166 vput(lowerrootvp); 167 return (error); 168 } 169 170 #ifdef UMAPFS_DIAGNOSTIC 171 printf("umap_mount:nentries %d\n",args.nentries); 172 for (i = 0; i < args.nentries; i++) 173 printf(" %ld maps to %ld\n", amp->info_mapdata[i][0], 174 amp->info_mapdata[i][1]); 175 #endif 176 177 error = copyin(args.gmapdata, amp->info_gmapdata, 178 2*sizeof(u_long)*args.gnentries); 179 if (error) { 180 vput(lowerrootvp); 181 return (error); 182 } 183 184 #ifdef UMAPFS_DIAGNOSTIC 185 printf("umap_mount:gnentries %d\n",args.gnentries); 186 for (i = 0; i < args.gnentries; i++) 187 printf("\tgroup %ld maps to %ld\n", 188 amp->info_gmapdata[i][0], 189 amp->info_gmapdata[i][1]); 190 #endif 191 192 /* 193 * Make sure the mount point's sufficiently initialized 194 * that the node create call will work. 195 */ 196 vfs_getnewfsid(mp); 197 amp->umapm_size = sizeof(struct umap_node); 198 amp->umapm_tag = VT_UMAP; 199 amp->umapm_bypass = umap_bypass; 200 amp->umapm_alloc = layer_node_alloc; /* the default alloc is fine */ 201 amp->umapm_vnodeop_p = umap_vnodeop_p; 202 simple_lock_init(&->umapm_hashlock); 203 amp->umapm_node_hashtbl = hashinit(NUMAPNODECACHE, HASH_LIST, M_CACHE, 204 M_WAITOK, &->umapm_node_hash); 205 206 207 /* 208 * fix up umap node for root vnode. 209 */ 210 error = layer_node_create(mp, lowerrootvp, &vp); 211 /* 212 * Make sure the node alias worked 213 */ 214 if (error) { 215 vput(lowerrootvp); 216 free(amp, M_UFSMNT); /* XXX */ 217 return (error); 218 } 219 /* 220 * Unlock the node (either the lower or the alias) 221 */ 222 VOP_UNLOCK(vp, 0); 223 224 /* 225 * Keep a held reference to the root vnode. 226 * It is vrele'd in umapfs_unmount. 227 */ 228 vp->v_flag |= VROOT; 229 amp->umapm_rootvp = vp; 230 231 error = set_statvfs_info(path, UIO_USERSPACE, args.umap_target, 232 UIO_USERSPACE, mp, p); 233 #ifdef UMAPFS_DIAGNOSTIC 234 printf("umapfs_mount: lower %s, alias at %s\n", 235 mp->mnt_stat.f_mntfromname, mp->mnt_stat.f_mntonname); 236 #endif 237 return error; 238 } 239 240 /* 241 * Free reference to umap layer 242 */ 243 int 244 umapfs_unmount(mp, mntflags, p) 245 struct mount *mp; 246 int mntflags; 247 struct proc *p; 248 { 249 struct vnode *rootvp = MOUNTTOUMAPMOUNT(mp)->umapm_rootvp; 250 int error; 251 int flags = 0; 252 253 #ifdef UMAPFS_DIAGNOSTIC 254 printf("umapfs_unmount(mp = %p)\n", mp); 255 #endif 256 257 if (mntflags & MNT_FORCE) 258 flags |= FORCECLOSE; 259 260 /* 261 * Clear out buffer cache. I don't think we 262 * ever get anything cached at this level at the 263 * moment, but who knows... 264 */ 265 #ifdef notyet 266 mntflushbuf(mp, 0); 267 if (mntinvalbuf(mp, 1)) 268 return (EBUSY); 269 #endif 270 if (rootvp->v_usecount > 1) 271 return (EBUSY); 272 if ((error = vflush(mp, rootvp, flags)) != 0) 273 return (error); 274 275 #ifdef UMAPFS_DIAGNOSTIC 276 vprint("alias root of lower", rootvp); 277 #endif 278 /* 279 * Release reference on underlying root vnode 280 */ 281 vrele(rootvp); 282 /* 283 * And blow it away for future re-use 284 */ 285 vgone(rootvp); 286 /* 287 * Finally, throw away the umap_mount structure 288 */ 289 free(mp->mnt_data, M_UFSMNT); /* XXX */ 290 mp->mnt_data = 0; 291 return (0); 292 } 293 294 SYSCTL_SETUP(sysctl_vfs_umap_setup, "sysctl vfs.umap subtree setup") 295 { 296 297 sysctl_createv(clog, 0, NULL, NULL, 298 CTLFLAG_PERMANENT, 299 CTLTYPE_NODE, "vfs", NULL, 300 NULL, 0, NULL, 0, 301 CTL_VFS, CTL_EOL); 302 sysctl_createv(clog, 0, NULL, NULL, 303 CTLFLAG_PERMANENT, 304 CTLTYPE_NODE, "umap", 305 SYSCTL_DESCR("UID/GID remapping file system"), 306 NULL, 0, NULL, 0, 307 CTL_VFS, 10, CTL_EOL); 308 /* 309 * XXX the "10" above could be dynamic, thereby eliminating 310 * one more instance of the "number to vfs" mapping problem, 311 * but "10" is the order as taken from sys/mount.h 312 */ 313 } 314 315 extern const struct vnodeopv_desc umapfs_vnodeop_opv_desc; 316 317 const struct vnodeopv_desc * const umapfs_vnodeopv_descs[] = { 318 &umapfs_vnodeop_opv_desc, 319 NULL, 320 }; 321 322 struct vfsops umapfs_vfsops = { 323 MOUNT_UMAP, 324 umapfs_mount, 325 layerfs_start, 326 umapfs_unmount, 327 layerfs_root, 328 layerfs_quotactl, 329 layerfs_statvfs, 330 layerfs_sync, 331 layerfs_vget, 332 layerfs_fhtovp, 333 layerfs_vptofh, 334 layerfs_init, 335 NULL, 336 layerfs_done, 337 NULL, 338 NULL, /* vfs_mountroot */ 339 layerfs_checkexp, 340 layerfs_snapshot, 341 umapfs_vnodeopv_descs, 342 }; 343