umap_vfsops.c revision 1.85
1 /* $NetBSD: umap_vfsops.c,v 1.85 2010/06/24 13:03:17 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 1.85 2010/06/24 13:03:17 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 <sys/kauth.h> 56 #include <sys/module.h> 57 58 #include <miscfs/umapfs/umap.h> 59 #include <miscfs/genfs/layer_extern.h> 60 61 MODULE(MODULE_CLASS_VFS, umap, "layerfs"); 62 63 VFS_PROTOS(umapfs); 64 65 static struct sysctllog *umapfs_sysctl_log; 66 67 /* 68 * Mount umap layer 69 */ 70 int 71 umapfs_mount(struct mount *mp, const char *path, void *data, size_t *data_len) 72 { 73 struct lwp *l = curlwp; 74 struct nameidata nd; 75 struct umap_args *args = data; 76 struct vnode *lowerrootvp, *vp; 77 struct umap_mount *amp; 78 int error; 79 #ifdef UMAPFS_DIAGNOSTIC 80 int i; 81 #endif 82 83 if (*data_len < sizeof *args) 84 return EINVAL; 85 86 if (mp->mnt_flag & MNT_GETARGS) { 87 amp = MOUNTTOUMAPMOUNT(mp); 88 if (amp == NULL) 89 return EIO; 90 args->la.target = NULL; 91 args->nentries = amp->info_nentries; 92 args->gnentries = amp->info_gnentries; 93 *data_len = sizeof *args; 94 return 0; 95 } 96 97 /* only for root */ 98 if ((error = kauth_authorize_generic(l->l_cred, KAUTH_GENERIC_ISSUSER, 99 NULL)) != 0) 100 return error; 101 102 #ifdef UMAPFS_DIAGNOSTIC 103 printf("umapfs_mount(mp = %p)\n", mp); 104 #endif 105 106 /* 107 * Update is not supported 108 */ 109 if (mp->mnt_flag & MNT_UPDATE) 110 return EOPNOTSUPP; 111 112 /* 113 * Find lower node 114 */ 115 NDINIT(&nd, LOOKUP, FOLLOW|LOCKLEAF, 116 UIO_USERSPACE, args->umap_target); 117 if ((error = namei(&nd)) != 0) 118 return (error); 119 120 /* 121 * Sanity check on lower vnode 122 */ 123 lowerrootvp = nd.ni_vp; 124 #ifdef UMAPFS_DIAGNOSTIC 125 printf("vp = %p, check for VDIR...\n", lowerrootvp); 126 #endif 127 128 if (lowerrootvp->v_type != VDIR) { 129 vput(lowerrootvp); 130 return (EINVAL); 131 } 132 133 #ifdef UMAPFS_DIAGNOSTIC 134 printf("mp = %p\n", mp); 135 #endif 136 137 amp = (struct umap_mount *) malloc(sizeof(struct umap_mount), 138 M_UFSMNT, M_WAITOK); /* XXX */ 139 memset(amp, 0, sizeof(struct umap_mount)); 140 141 mp->mnt_data = amp; 142 amp->umapm_vfs = lowerrootvp->v_mount; 143 if (amp->umapm_vfs->mnt_flag & MNT_LOCAL) 144 mp->mnt_flag |= MNT_LOCAL; 145 146 /* 147 * Now copy in the number of entries and maps for umap mapping. 148 */ 149 if (args->nentries > MAPFILEENTRIES || args->gnentries > GMAPFILEENTRIES) { 150 vput(lowerrootvp); 151 return (error); 152 } 153 154 amp->info_nentries = args->nentries; 155 amp->info_gnentries = args->gnentries; 156 error = copyin(args->mapdata, amp->info_mapdata, 157 2*sizeof(u_long)*args->nentries); 158 if (error) { 159 vput(lowerrootvp); 160 return (error); 161 } 162 163 #ifdef UMAPFS_DIAGNOSTIC 164 printf("umap_mount:nentries %d\n",args->nentries); 165 for (i = 0; i < args->nentries; i++) 166 printf(" %ld maps to %ld\n", amp->info_mapdata[i][0], 167 amp->info_mapdata[i][1]); 168 #endif 169 170 error = copyin(args->gmapdata, amp->info_gmapdata, 171 2*sizeof(u_long)*args->gnentries); 172 if (error) { 173 vput(lowerrootvp); 174 return (error); 175 } 176 177 #ifdef UMAPFS_DIAGNOSTIC 178 printf("umap_mount:gnentries %d\n",args->gnentries); 179 for (i = 0; i < args->gnentries; i++) 180 printf("\tgroup %ld maps to %ld\n", 181 amp->info_gmapdata[i][0], 182 amp->info_gmapdata[i][1]); 183 #endif 184 185 /* 186 * Make sure the mount point's sufficiently initialized 187 * that the node create call will work. 188 */ 189 vfs_getnewfsid(mp); 190 amp->umapm_size = sizeof(struct umap_node); 191 amp->umapm_tag = VT_UMAP; 192 amp->umapm_bypass = umap_bypass; 193 amp->umapm_alloc = layer_node_alloc; /* the default alloc is fine */ 194 amp->umapm_vnodeop_p = umap_vnodeop_p; 195 mutex_init(&->umapm_hashlock, MUTEX_DEFAULT, IPL_NONE); 196 amp->umapm_node_hashtbl = hashinit(NUMAPNODECACHE, HASH_LIST, true, 197 &->umapm_node_hash); 198 199 200 /* 201 * fix up umap node for root vnode. 202 */ 203 error = layer_node_create(mp, lowerrootvp, &vp); 204 /* 205 * Make sure the node alias worked 206 */ 207 if (error) { 208 vput(lowerrootvp); 209 hashdone(amp->umapm_node_hashtbl, HASH_LIST, 210 amp->umapm_node_hash); 211 free(amp, M_UFSMNT); /* XXX */ 212 return (error); 213 } 214 /* 215 * Unlock the node (either the lower or the alias) 216 */ 217 vp->v_vflag |= VV_ROOT; 218 VOP_UNLOCK(vp); 219 220 /* 221 * Keep a held reference to the root vnode. 222 * It is vrele'd in umapfs_unmount. 223 */ 224 amp->umapm_rootvp = vp; 225 226 error = set_statvfs_info(path, UIO_USERSPACE, args->umap_target, 227 UIO_USERSPACE, mp->mnt_op->vfs_name, mp, l); 228 #ifdef UMAPFS_DIAGNOSTIC 229 printf("umapfs_mount: lower %s, alias at %s\n", 230 mp->mnt_stat.f_mntfromname, mp->mnt_stat.f_mntonname); 231 #endif 232 return error; 233 } 234 235 /* 236 * Free reference to umap layer 237 */ 238 int 239 umapfs_unmount(struct mount *mp, int mntflags) 240 { 241 struct umap_mount *amp = MOUNTTOUMAPMOUNT(mp); 242 struct vnode *rtvp = amp->umapm_rootvp; 243 int error; 244 int flags = 0; 245 246 #ifdef UMAPFS_DIAGNOSTIC 247 printf("umapfs_unmount(mp = %p)\n", mp); 248 #endif 249 250 if (mntflags & MNT_FORCE) 251 flags |= FORCECLOSE; 252 253 if (rtvp->v_usecount > 1 && (mntflags & MNT_FORCE) == 0) 254 return (EBUSY); 255 if ((error = vflush(mp, rtvp, flags)) != 0) 256 return (error); 257 258 #ifdef UMAPFS_DIAGNOSTIC 259 vprint("alias root of lower", rtvp); 260 #endif 261 /* 262 * Blow it away for future re-use 263 */ 264 vgone(rtvp); 265 /* 266 * Finally, throw away the umap_mount structure 267 */ 268 mutex_destroy(&->umapm_hashlock); 269 hashdone(amp->umapm_node_hashtbl, HASH_LIST, amp->umapm_node_hash); 270 free(amp, M_UFSMNT); /* XXX */ 271 mp->mnt_data = NULL; 272 return (0); 273 } 274 275 extern const struct vnodeopv_desc umapfs_vnodeop_opv_desc; 276 277 const struct vnodeopv_desc * const umapfs_vnodeopv_descs[] = { 278 &umapfs_vnodeop_opv_desc, 279 NULL, 280 }; 281 282 struct vfsops umapfs_vfsops = { 283 MOUNT_UMAP, 284 sizeof (struct umap_args), 285 umapfs_mount, 286 layerfs_start, 287 umapfs_unmount, 288 layerfs_root, 289 layerfs_quotactl, 290 layerfs_statvfs, 291 layerfs_sync, 292 layerfs_vget, 293 layerfs_fhtovp, 294 layerfs_vptofh, 295 layerfs_init, 296 NULL, 297 layerfs_done, 298 NULL, /* vfs_mountroot */ 299 layerfs_snapshot, 300 vfs_stdextattrctl, 301 (void *)eopnotsupp, /* vfs_suspendctl */ 302 layerfs_renamelock_enter, 303 layerfs_renamelock_exit, 304 (void *)eopnotsupp, 305 umapfs_vnodeopv_descs, 306 0, /* vfs_refcount */ 307 { NULL, NULL }, 308 }; 309 310 static int 311 umap_modcmd(modcmd_t cmd, void *arg) 312 { 313 int error; 314 315 switch (cmd) { 316 case MODULE_CMD_INIT: 317 error = vfs_attach(&umapfs_vfsops); 318 if (error != 0) 319 break; 320 sysctl_createv(&umapfs_sysctl_log, 0, NULL, NULL, 321 CTLFLAG_PERMANENT, 322 CTLTYPE_NODE, "vfs", NULL, 323 NULL, 0, NULL, 0, 324 CTL_VFS, CTL_EOL); 325 sysctl_createv(&umapfs_sysctl_log, 0, NULL, NULL, 326 CTLFLAG_PERMANENT, 327 CTLTYPE_NODE, "umap", 328 SYSCTL_DESCR("UID/GID remapping file system"), 329 NULL, 0, NULL, 0, 330 CTL_VFS, 10, CTL_EOL); 331 /* 332 * XXX the "10" above could be dynamic, thereby eliminating 333 * one more instance of the "number to vfs" mapping problem, 334 * but "10" is the order as taken from sys/mount.h 335 */ 336 break; 337 case MODULE_CMD_FINI: 338 error = vfs_detach(&umapfs_vfsops); 339 if (error != 0) 340 break; 341 sysctl_teardown(&umapfs_sysctl_log); 342 break; 343 default: 344 error = ENOTTY; 345 break; 346 } 347 348 return (error); 349 } 350
Indexes created Mon Sep 22 13:09:51 GMT 2025