umap_vfsops.c revision 1.79
1 /* $NetBSD: umap_vfsops.c,v 1.79 2008/05/13 08:31:13 simonb 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 1.79 2008/05/13 08:31:13 simonb 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 /* 66 * Mount umap layer 67 */ 68 int 69 umapfs_mount(mp, path, data, data_len) 70 struct mount *mp; 71 const char *path; 72 void *data; 73 size_t *data_len; 74 { 75 struct lwp *l = curlwp; 76 struct nameidata nd; 77 struct umap_args *args = data; 78 struct vnode *lowerrootvp, *vp; 79 struct umap_mount *amp; 80 int error; 81 #ifdef UMAPFS_DIAGNOSTIC 82 int i; 83 #endif 84 85 if (*data_len < sizeof *args) 86 return EINVAL; 87 88 if (mp->mnt_flag & MNT_GETARGS) { 89 amp = MOUNTTOUMAPMOUNT(mp); 90 if (amp == NULL) 91 return EIO; 92 args->la.target = NULL; 93 args->nentries = amp->info_nentries; 94 args->gnentries = amp->info_gnentries; 95 *data_len = sizeof *args; 96 return 0; 97 } 98 99 /* only for root */ 100 if ((error = kauth_authorize_generic(l->l_cred, KAUTH_GENERIC_ISSUSER, 101 NULL)) != 0) 102 return error; 103 104 #ifdef UMAPFS_DIAGNOSTIC 105 printf("umapfs_mount(mp = %p)\n", mp); 106 #endif 107 108 /* 109 * Update is not supported 110 */ 111 if (mp->mnt_flag & MNT_UPDATE) 112 return EOPNOTSUPP; 113 114 /* 115 * Find lower node 116 */ 117 NDINIT(&nd, LOOKUP, FOLLOW|LOCKLEAF, 118 UIO_USERSPACE, args->umap_target); 119 if ((error = namei(&nd)) != 0) 120 return (error); 121 122 /* 123 * Sanity check on lower vnode 124 */ 125 lowerrootvp = nd.ni_vp; 126 #ifdef UMAPFS_DIAGNOSTIC 127 printf("vp = %p, check for VDIR...\n", lowerrootvp); 128 #endif 129 130 if (lowerrootvp->v_type != VDIR) { 131 vput(lowerrootvp); 132 return (EINVAL); 133 } 134 135 #ifdef UMAPFS_DIAGNOSTIC 136 printf("mp = %p\n", mp); 137 #endif 138 139 amp = (struct umap_mount *) malloc(sizeof(struct umap_mount), 140 M_UFSMNT, M_WAITOK); /* XXX */ 141 memset(amp, 0, sizeof(struct umap_mount)); 142 143 mp->mnt_data = amp; 144 amp->umapm_vfs = lowerrootvp->v_mount; 145 if (amp->umapm_vfs->mnt_flag & MNT_LOCAL) 146 mp->mnt_flag |= MNT_LOCAL; 147 148 /* 149 * Now copy in the number of entries and maps for umap mapping. 150 */ 151 if (args->nentries > MAPFILEENTRIES || args->gnentries > GMAPFILEENTRIES) { 152 vput(lowerrootvp); 153 return (error); 154 } 155 156 amp->info_nentries = args->nentries; 157 amp->info_gnentries = args->gnentries; 158 error = copyin(args->mapdata, amp->info_mapdata, 159 2*sizeof(u_long)*args->nentries); 160 if (error) { 161 vput(lowerrootvp); 162 return (error); 163 } 164 165 #ifdef UMAPFS_DIAGNOSTIC 166 printf("umap_mount:nentries %d\n",args->nentries); 167 for (i = 0; i < args->nentries; i++) 168 printf(" %ld maps to %ld\n", amp->info_mapdata[i][0], 169 amp->info_mapdata[i][1]); 170 #endif 171 172 error = copyin(args->gmapdata, amp->info_gmapdata, 173 2*sizeof(u_long)*args->gnentries); 174 if (error) { 175 vput(lowerrootvp); 176 return (error); 177 } 178 179 #ifdef UMAPFS_DIAGNOSTIC 180 printf("umap_mount:gnentries %d\n",args->gnentries); 181 for (i = 0; i < args->gnentries; i++) 182 printf("\tgroup %ld maps to %ld\n", 183 amp->info_gmapdata[i][0], 184 amp->info_gmapdata[i][1]); 185 #endif 186 187 /* 188 * Make sure the mount point's sufficiently initialized 189 * that the node create call will work. 190 */ 191 vfs_getnewfsid(mp); 192 amp->umapm_size = sizeof(struct umap_node); 193 amp->umapm_tag = VT_UMAP; 194 amp->umapm_bypass = umap_bypass; 195 amp->umapm_alloc = layer_node_alloc; /* the default alloc is fine */ 196 amp->umapm_vnodeop_p = umap_vnodeop_p; 197 mutex_init(&->umapm_hashlock, MUTEX_DEFAULT, IPL_NONE); 198 amp->umapm_node_hashtbl = hashinit(NUMAPNODECACHE, HASH_LIST, true, 199 &->umapm_node_hash); 200 201 202 /* 203 * fix up umap node for root vnode. 204 */ 205 error = layer_node_create(mp, lowerrootvp, &vp); 206 /* 207 * Make sure the node alias worked 208 */ 209 if (error) { 210 vput(lowerrootvp); 211 hashdone(amp->umapm_node_hashtbl, HASH_LIST, 212 amp->umapm_node_hash); 213 free(amp, M_UFSMNT); /* XXX */ 214 return (error); 215 } 216 /* 217 * Unlock the node (either the lower or the alias) 218 */ 219 vp->v_vflag |= VV_ROOT; 220 VOP_UNLOCK(vp, 0); 221 222 /* 223 * Keep a held reference to the root vnode. 224 * It is vrele'd in umapfs_unmount. 225 */ 226 amp->umapm_rootvp = vp; 227 228 error = set_statvfs_info(path, UIO_USERSPACE, args->umap_target, 229 UIO_USERSPACE, mp->mnt_op->vfs_name, mp, l); 230 #ifdef UMAPFS_DIAGNOSTIC 231 printf("umapfs_mount: lower %s, alias at %s\n", 232 mp->mnt_stat.f_mntfromname, mp->mnt_stat.f_mntonname); 233 #endif 234 return error; 235 } 236 237 /* 238 * Free reference to umap layer 239 */ 240 int 241 umapfs_unmount(struct mount *mp, int mntflags) 242 { 243 struct umap_mount *amp = MOUNTTOUMAPMOUNT(mp); 244 struct vnode *rtvp = amp->umapm_rootvp; 245 int error; 246 int flags = 0; 247 248 #ifdef UMAPFS_DIAGNOSTIC 249 printf("umapfs_unmount(mp = %p)\n", mp); 250 #endif 251 252 if (mntflags & MNT_FORCE) 253 flags |= FORCECLOSE; 254 255 if (rtvp->v_usecount > 1 && (mntflags & MNT_FORCE) == 0) 256 return (EBUSY); 257 if ((error = vflush(mp, rtvp, flags)) != 0) 258 return (error); 259 260 #ifdef UMAPFS_DIAGNOSTIC 261 vprint("alias root of lower", rtvp); 262 #endif 263 /* 264 * Blow it away for future re-use 265 */ 266 vgone(rtvp); 267 /* 268 * Finally, throw away the umap_mount structure 269 */ 270 mutex_destroy(&->umapm_hashlock); 271 hashdone(amp->umapm_node_hashtbl, HASH_LIST, amp->umapm_node_hash); 272 free(amp, M_UFSMNT); /* XXX */ 273 mp->mnt_data = NULL; 274 return (0); 275 } 276 277 SYSCTL_SETUP(sysctl_vfs_umap_setup, "sysctl vfs.umap subtree setup") 278 { 279 280 sysctl_createv(clog, 0, NULL, NULL, 281 CTLFLAG_PERMANENT, 282 CTLTYPE_NODE, "vfs", NULL, 283 NULL, 0, NULL, 0, 284 CTL_VFS, CTL_EOL); 285 sysctl_createv(clog, 0, NULL, NULL, 286 CTLFLAG_PERMANENT, 287 CTLTYPE_NODE, "umap", 288 SYSCTL_DESCR("UID/GID remapping file system"), 289 NULL, 0, NULL, 0, 290 CTL_VFS, 10, CTL_EOL); 291 /* 292 * XXX the "10" above could be dynamic, thereby eliminating 293 * one more instance of the "number to vfs" mapping problem, 294 * but "10" is the order as taken from sys/mount.h 295 */ 296 } 297 298 extern const struct vnodeopv_desc umapfs_vnodeop_opv_desc; 299 300 const struct vnodeopv_desc * const umapfs_vnodeopv_descs[] = { 301 &umapfs_vnodeop_opv_desc, 302 NULL, 303 }; 304 305 struct vfsops umapfs_vfsops = { 306 MOUNT_UMAP, 307 sizeof (struct umap_args), 308 umapfs_mount, 309 layerfs_start, 310 umapfs_unmount, 311 layerfs_root, 312 layerfs_quotactl, 313 layerfs_statvfs, 314 layerfs_sync, 315 layerfs_vget, 316 layerfs_fhtovp, 317 layerfs_vptofh, 318 layerfs_init, 319 NULL, 320 layerfs_done, 321 NULL, /* vfs_mountroot */ 322 layerfs_snapshot, 323 vfs_stdextattrctl, 324 (void *)eopnotsupp, /* vfs_suspendctl */ 325 layerfs_renamelock_enter, 326 layerfs_renamelock_exit, 327 (void *)eopnotsupp, 328 umapfs_vnodeopv_descs, 329 0, /* vfs_refcount */ 330 { NULL, NULL }, 331 }; 332 333 static int 334 umapfs_modcmd(modcmd_t cmd, void *arg) 335 { 336 337 switch (cmd) { 338 case MODULE_CMD_INIT: 339 return vfs_attach(&umapfs_vfsops); 340 case MODULE_CMD_FINI: 341 return vfs_detach(&umapfs_vfsops); 342 default: 343 return ENOTTY; 344 } 345 } 346
Indexes created Tue Sep 23 14:10:03 GMT 2025