1 /* $NetBSD: umap_vfsops.c,v 1.56 2005/12/11 12:24:51 christos 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 1.56 2005/12/11 12:24:51 christos 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(struct mount *, const char *, void *, 59 struct nameidata *, struct lwp *); 60 int umapfs_unmount(struct mount *, int, struct lwp *); 61 62 /* 63 * Mount umap layer 64 */ 65 int 66 umapfs_mount(mp, path, data, ndp, l) 67 struct mount *mp; 68 const char *path; 69 void *data; 70 struct nameidata *ndp; 71 struct lwp *l; 72 { 73 struct umap_args args; 74 struct vnode *lowerrootvp, *vp; 75 struct umap_mount *amp; 76 struct proc *p = l->l_proc; 77 int error; 78 #ifdef UMAPFS_DIAGNOSTIC 79 int i; 80 #endif 81 82 if (mp->mnt_flag & MNT_GETARGS) { 83 amp = MOUNTTOUMAPMOUNT(mp); 84 if (amp == NULL) 85 return EIO; 86 args.la.target = NULL; 87 args.nentries = amp->info_nentries; 88 args.gnentries = amp->info_gnentries; 89 return copyout(&args, data, sizeof(args)); 90 } 91 92 /* only for root */ 93 if ((error = suser(p->p_ucred, &p->p_acflag)) != 0) 94 return error; 95 96 #ifdef UMAPFS_DIAGNOSTIC 97 printf("umapfs_mount(mp = %p)\n", mp); 98 #endif 99 100 /* 101 * Get argument 102 */ 103 error = copyin(data, &args, sizeof(struct umap_args)); 104 if (error) 105 return (error); 106 107 /* 108 * Update is not supported 109 */ 110 if (mp->mnt_flag & MNT_UPDATE) 111 return EOPNOTSUPP; 112 113 /* 114 * Find lower node 115 */ 116 NDINIT(ndp, LOOKUP, FOLLOW|LOCKLEAF, 117 UIO_USERSPACE, args.umap_target, l); 118 if ((error = namei(ndp)) != 0) 119 return (error); 120 121 /* 122 * Sanity check on lower vnode 123 */ 124 lowerrootvp = ndp->ni_vp; 125 #ifdef UMAPFS_DIAGNOSTIC 126 printf("vp = %p, check for VDIR...\n", lowerrootvp); 127 #endif 128 129 if (lowerrootvp->v_type != VDIR) { 130 vput(lowerrootvp); 131 return (EINVAL); 132 } 133 134 #ifdef UMAPFS_DIAGNOSTIC 135 printf("mp = %p\n", mp); 136 #endif 137 138 amp = (struct umap_mount *) malloc(sizeof(struct umap_mount), 139 M_UFSMNT, M_WAITOK); /* XXX */ 140 memset(amp, 0, sizeof(struct umap_mount)); 141 142 mp->mnt_data = amp; 143 mp->mnt_leaf = lowerrootvp->v_mount->mnt_leaf; 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 simple_lock_init(&->umapm_hashlock); 198 amp->umapm_node_hashtbl = hashinit(NUMAPNODECACHE, HASH_LIST, M_CACHE, 199 M_WAITOK, &->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 free(amp, M_UFSMNT); /* XXX */ 212 return (error); 213 } 214 /* 215 * Unlock the node (either the lower or the alias) 216 */ 217 VOP_UNLOCK(vp, 0); 218 219 /* 220 * Keep a held reference to the root vnode. 221 * It is vrele'd in umapfs_unmount. 222 */ 223 vp->v_flag |= VROOT; 224 amp->umapm_rootvp = vp; 225 226 error = set_statvfs_info(path, UIO_USERSPACE, args.umap_target, 227 UIO_USERSPACE, 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(mp, mntflags, l) 240 struct mount *mp; 241 int mntflags; 242 struct lwp *l; 243 { 244 struct vnode *rtvp = MOUNTTOUMAPMOUNT(mp)->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 /* 256 * Clear out buffer cache. I don't think we 257 * ever get anything cached at this level at the 258 * moment, but who knows... 259 */ 260 #ifdef notyet 261 mntflushbuf(mp, 0); 262 if (mntinvalbuf(mp, 1)) 263 return (EBUSY); 264 #endif 265 if (rtvp->v_usecount > 1) 266 return (EBUSY); 267 if ((error = vflush(mp, rtvp, flags)) != 0) 268 return (error); 269 270 #ifdef UMAPFS_DIAGNOSTIC 271 vprint("alias root of lower", rtvp); 272 #endif 273 /* 274 * Release reference on underlying root vnode 275 */ 276 vrele(rtvp); 277 /* 278 * And blow it away for future re-use 279 */ 280 vgone(rtvp); 281 /* 282 * Finally, throw away the umap_mount structure 283 */ 284 free(mp->mnt_data, M_UFSMNT); /* XXX */ 285 mp->mnt_data = 0; 286 return (0); 287 } 288 289 SYSCTL_SETUP(sysctl_vfs_umap_setup, "sysctl vfs.umap subtree setup") 290 { 291 292 sysctl_createv(clog, 0, NULL, NULL, 293 CTLFLAG_PERMANENT, 294 CTLTYPE_NODE, "vfs", NULL, 295 NULL, 0, NULL, 0, 296 CTL_VFS, CTL_EOL); 297 sysctl_createv(clog, 0, NULL, NULL, 298 CTLFLAG_PERMANENT, 299 CTLTYPE_NODE, "umap", 300 SYSCTL_DESCR("UID/GID remapping file system"), 301 NULL, 0, NULL, 0, 302 CTL_VFS, 10, CTL_EOL); 303 /* 304 * XXX the "10" above could be dynamic, thereby eliminating 305 * one more instance of the "number to vfs" mapping problem, 306 * but "10" is the order as taken from sys/mount.h 307 */ 308 } 309 310 extern const struct vnodeopv_desc umapfs_vnodeop_opv_desc; 311 312 const struct vnodeopv_desc * const umapfs_vnodeopv_descs[] = { 313 &umapfs_vnodeop_opv_desc, 314 NULL, 315 }; 316 317 struct vfsops umapfs_vfsops = { 318 MOUNT_UMAP, 319 umapfs_mount, 320 layerfs_start, 321 umapfs_unmount, 322 layerfs_root, 323 layerfs_quotactl, 324 layerfs_statvfs, 325 layerfs_sync, 326 layerfs_vget, 327 layerfs_fhtovp, 328 layerfs_vptofh, 329 layerfs_init, 330 NULL, 331 layerfs_done, 332 NULL, /* vfs_mountroot */ 333 layerfs_snapshot, 334 vfs_stdextattrctl, 335 umapfs_vnodeopv_descs, 336 }; 337 VFS_ATTACH(umapfs_vfsops); 338