umap_vfsops.c revision 1.80.16.1
1 /* $NetBSD: umap_vfsops.c,v 1.80.16.1 2014/04/28 16:05:37 sborrill 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 1.80.16.1 2014/04/28 16:05:37 sborrill 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, umapfs, NULL); 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(mp, path, data, data_len) 72 struct mount *mp; 73 const char *path; 74 void *data; 75 size_t *data_len; 76 { 77 struct lwp *l = curlwp; 78 struct nameidata nd; 79 struct umap_args *args = data; 80 struct vnode *lowerrootvp, *vp; 81 struct umap_mount *amp; 82 int error; 83 #ifdef UMAPFS_DIAGNOSTIC 84 int i; 85 #endif 86 87 if (args == NULL) 88 return EINVAL; 89 if (*data_len < sizeof *args) 90 return EINVAL; 91 92 if (mp->mnt_flag & MNT_GETARGS) { 93 amp = MOUNTTOUMAPMOUNT(mp); 94 if (amp == NULL) 95 return EIO; 96 args->la.target = NULL; 97 args->nentries = amp->info_nentries; 98 args->gnentries = amp->info_gnentries; 99 *data_len = sizeof *args; 100 return 0; 101 } 102 103 /* only for root */ 104 if ((error = kauth_authorize_generic(l->l_cred, KAUTH_GENERIC_ISSUSER, 105 NULL)) != 0) 106 return error; 107 108 #ifdef UMAPFS_DIAGNOSTIC 109 printf("umapfs_mount(mp = %p)\n", mp); 110 #endif 111 112 /* 113 * Update is not supported 114 */ 115 if (mp->mnt_flag & MNT_UPDATE) 116 return EOPNOTSUPP; 117 118 /* 119 * Find lower node 120 */ 121 NDINIT(&nd, LOOKUP, FOLLOW|LOCKLEAF, 122 UIO_USERSPACE, args->umap_target); 123 if ((error = namei(&nd)) != 0) 124 return (error); 125 126 /* 127 * Sanity check on lower vnode 128 */ 129 lowerrootvp = nd.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 amp->umapm_vfs = lowerrootvp->v_mount; 149 if (amp->umapm_vfs->mnt_flag & MNT_LOCAL) 150 mp->mnt_flag |= MNT_LOCAL; 151 152 /* 153 * Now copy in the number of entries and maps for umap mapping. 154 */ 155 if (args->nentries > MAPFILEENTRIES || args->gnentries > GMAPFILEENTRIES) { 156 vput(lowerrootvp); 157 return (error); 158 } 159 160 amp->info_nentries = args->nentries; 161 amp->info_gnentries = args->gnentries; 162 error = copyin(args->mapdata, amp->info_mapdata, 163 2*sizeof(u_long)*args->nentries); 164 if (error) { 165 vput(lowerrootvp); 166 return (error); 167 } 168 169 #ifdef UMAPFS_DIAGNOSTIC 170 printf("umap_mount:nentries %d\n",args->nentries); 171 for (i = 0; i < args->nentries; i++) 172 printf(" %ld maps to %ld\n", amp->info_mapdata[i][0], 173 amp->info_mapdata[i][1]); 174 #endif 175 176 error = copyin(args->gmapdata, amp->info_gmapdata, 177 2*sizeof(u_long)*args->gnentries); 178 if (error) { 179 vput(lowerrootvp); 180 return (error); 181 } 182 183 #ifdef UMAPFS_DIAGNOSTIC 184 printf("umap_mount:gnentries %d\n",args->gnentries); 185 for (i = 0; i < args->gnentries; i++) 186 printf("\tgroup %ld maps to %ld\n", 187 amp->info_gmapdata[i][0], 188 amp->info_gmapdata[i][1]); 189 #endif 190 191 /* 192 * Make sure the mount point's sufficiently initialized 193 * that the node create call will work. 194 */ 195 vfs_getnewfsid(mp); 196 amp->umapm_size = sizeof(struct umap_node); 197 amp->umapm_tag = VT_UMAP; 198 amp->umapm_bypass = umap_bypass; 199 amp->umapm_alloc = layer_node_alloc; /* the default alloc is fine */ 200 amp->umapm_vnodeop_p = umap_vnodeop_p; 201 mutex_init(&->umapm_hashlock, MUTEX_DEFAULT, IPL_NONE); 202 amp->umapm_node_hashtbl = hashinit(NUMAPNODECACHE, HASH_LIST, true, 203 &->umapm_node_hash); 204 205 206 /* 207 * fix up umap node for root vnode. 208 */ 209 error = layer_node_create(mp, lowerrootvp, &vp); 210 /* 211 * Make sure the node alias worked 212 */ 213 if (error) { 214 vput(lowerrootvp); 215 hashdone(amp->umapm_node_hashtbl, HASH_LIST, 216 amp->umapm_node_hash); 217 free(amp, M_UFSMNT); /* XXX */ 218 return (error); 219 } 220 /* 221 * Unlock the node (either the lower or the alias) 222 */ 223 vp->v_vflag |= VV_ROOT; 224 VOP_UNLOCK(vp, 0); 225 226 /* 227 * Keep a held reference to the root vnode. 228 * It is vrele'd in umapfs_unmount. 229 */ 230 amp->umapm_rootvp = vp; 231 232 error = set_statvfs_info(path, UIO_USERSPACE, args->umap_target, 233 UIO_USERSPACE, mp->mnt_op->vfs_name, mp, l); 234 #ifdef UMAPFS_DIAGNOSTIC 235 printf("umapfs_mount: lower %s, alias at %s\n", 236 mp->mnt_stat.f_mntfromname, mp->mnt_stat.f_mntonname); 237 #endif 238 return error; 239 } 240 241 /* 242 * Free reference to umap layer 243 */ 244 int 245 umapfs_unmount(struct mount *mp, int mntflags) 246 { 247 struct umap_mount *amp = MOUNTTOUMAPMOUNT(mp); 248 struct vnode *rtvp = amp->umapm_rootvp; 249 int error; 250 int flags = 0; 251 252 #ifdef UMAPFS_DIAGNOSTIC 253 printf("umapfs_unmount(mp = %p)\n", mp); 254 #endif 255 256 if (mntflags & MNT_FORCE) 257 flags |= FORCECLOSE; 258 259 if (rtvp->v_usecount > 1 && (mntflags & MNT_FORCE) == 0) 260 return (EBUSY); 261 if ((error = vflush(mp, rtvp, flags)) != 0) 262 return (error); 263 264 #ifdef UMAPFS_DIAGNOSTIC 265 vprint("alias root of lower", rtvp); 266 #endif 267 /* 268 * Blow it away for future re-use 269 */ 270 vgone(rtvp); 271 /* 272 * Finally, throw away the umap_mount structure 273 */ 274 mutex_destroy(&->umapm_hashlock); 275 hashdone(amp->umapm_node_hashtbl, HASH_LIST, amp->umapm_node_hash); 276 free(amp, M_UFSMNT); /* XXX */ 277 mp->mnt_data = NULL; 278 return (0); 279 } 280 281 extern const struct vnodeopv_desc umapfs_vnodeop_opv_desc; 282 283 const struct vnodeopv_desc * const umapfs_vnodeopv_descs[] = { 284 &umapfs_vnodeop_opv_desc, 285 NULL, 286 }; 287 288 struct vfsops umapfs_vfsops = { 289 MOUNT_UMAP, 290 sizeof (struct umap_args), 291 umapfs_mount, 292 layerfs_start, 293 umapfs_unmount, 294 layerfs_root, 295 layerfs_quotactl, 296 layerfs_statvfs, 297 layerfs_sync, 298 layerfs_vget, 299 layerfs_fhtovp, 300 layerfs_vptofh, 301 layerfs_init, 302 NULL, 303 layerfs_done, 304 NULL, /* vfs_mountroot */ 305 layerfs_snapshot, 306 vfs_stdextattrctl, 307 (void *)eopnotsupp, /* vfs_suspendctl */ 308 layerfs_renamelock_enter, 309 layerfs_renamelock_exit, 310 (void *)eopnotsupp, 311 umapfs_vnodeopv_descs, 312 0, /* vfs_refcount */ 313 { NULL, NULL }, 314 }; 315 316 static int 317 umapfs_modcmd(modcmd_t cmd, void *arg) 318 { 319 int error; 320 321 switch (cmd) { 322 case MODULE_CMD_INIT: 323 error = vfs_attach(&umapfs_vfsops); 324 if (error != 0) 325 break; 326 sysctl_createv(&umapfs_sysctl_log, 0, NULL, NULL, 327 CTLFLAG_PERMANENT, 328 CTLTYPE_NODE, "vfs", NULL, 329 NULL, 0, NULL, 0, 330 CTL_VFS, CTL_EOL); 331 sysctl_createv(&umapfs_sysctl_log, 0, NULL, NULL, 332 CTLFLAG_PERMANENT, 333 CTLTYPE_NODE, "umap", 334 SYSCTL_DESCR("UID/GID remapping file system"), 335 NULL, 0, NULL, 0, 336 CTL_VFS, 10, CTL_EOL); 337 /* 338 * XXX the "10" above could be dynamic, thereby eliminating 339 * one more instance of the "number to vfs" mapping problem, 340 * but "10" is the order as taken from sys/mount.h 341 */ 342 break; 343 case MODULE_CMD_FINI: 344 error = vfs_detach(&umapfs_vfsops); 345 if (error != 0) 346 break; 347 sysctl_teardown(&umapfs_sysctl_log); 348 break; 349 default: 350 error = ENOTTY; 351 break; 352 } 353 354 return (error); 355 } 356
Indexes created Tue Oct 07 21:09:53 GMT 2025