1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 /* 22 * Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved. 23 */ 24 25 /* 26 * vnode ops for the /dev/vt directory 27 */ 28 29 #include <sys/types.h> 30 #include <sys/param.h> 31 #include <sys/sysmacros.h> 32 #include <sys/sunndi.h> 33 #include <fs/fs_subr.h> 34 #include <sys/fs/dv_node.h> 35 #include <sys/fs/sdev_impl.h> 36 #include <sys/policy.h> 37 #include <sys/stat.h> 38 #include <sys/vfs_opreg.h> 39 #include <sys/tty.h> 40 #include <sys/vt_impl.h> 41 #include <sys/note.h> 42 43 /* warlock in this file only cares about variables shared by vt and devfs */ 44 _NOTE(SCHEME_PROTECTS_DATA("Do not care", sdev_node vattr vnode)) 45 46 #define DEVVT_UID_DEFAULT SDEV_UID_DEFAULT 47 #define DEVVT_GID_DEFAULT (0) 48 #define DEVVT_DEVMODE_DEFAULT (0600) 49 #define DEVVT_ACTIVE_NAME "active" 50 #define DEVVT_CONSUSER_NAME "console_user" 51 52 #define isdigit(ch) ((ch) >= '0' && (ch) <= '9') 53 54 /* attributes for VT nodes */ 55 static vattr_t devvt_vattr = { 56 AT_TYPE|AT_MODE|AT_UID|AT_GID, /* va_mask */ 57 VCHR, /* va_type */ 58 S_IFCHR | DEVVT_DEVMODE_DEFAULT, /* va_mode */ 59 DEVVT_UID_DEFAULT, /* va_uid */ 60 DEVVT_GID_DEFAULT, /* va_gid */ 61 0 /* 0 hereafter */ 62 }; 63 64 struct vnodeops *devvt_vnodeops; 65 66 struct vnodeops * 67 devvt_getvnodeops(void) 68 { 69 return (devvt_vnodeops); 70 } 71 72 static int 73 devvt_str2minor(const char *nm, minor_t *mp) 74 { 75 long uminor = 0; 76 char *endptr = NULL; 77 78 if (nm == NULL || !isdigit(*nm)) 79 return (EINVAL); 80 81 *mp = 0; 82 if (ddi_strtol(nm, &endptr, 10, &uminor) != 0 || 83 *endptr != '\0' || uminor < 0) { 84 return (EINVAL); 85 } 86 87 *mp = (minor_t)uminor; 88 return (0); 89 } 90 91 /* 92 * Validate that a node is up-to-date and correct. 93 * A validator may not update the node state or 94 * contents as a read lock permits entry by 95 * multiple threads. 96 */ 97 int 98 devvt_validate(struct sdev_node *dv) 99 { 100 minor_t min; 101 char *nm = dv->sdev_name; 102 int rval; 103 104 ASSERT(dv->sdev_state == SDEV_READY); 105 ASSERT(RW_LOCK_HELD(&(dv->sdev_dotdot)->sdev_contents)); 106 107 /* validate only READY nodes */ 108 if (dv->sdev_state != SDEV_READY) { 109 sdcmn_err(("dev fs: skipping: node not ready %s(%p)", 110 nm, (void *)dv)); 111 return (SDEV_VTOR_SKIP); 112 } 113 114 if (vt_wc_attached() == (major_t)-1) 115 return (SDEV_VTOR_INVALID); 116 117 if (strcmp(nm, DEVVT_ACTIVE_NAME) == 0) { 118 char *link = kmem_zalloc(MAXPATHLEN, KM_SLEEP); 119 (void) vt_getactive(link, MAXPATHLEN); 120 rval = (strcmp(link, dv->sdev_symlink) == 0) ? 121 SDEV_VTOR_VALID : SDEV_VTOR_STALE; 122 kmem_free(link, MAXPATHLEN); 123 return (rval); 124 } 125 126 if (strcmp(nm, DEVVT_CONSUSER_NAME) == 0) { 127 char *link = kmem_zalloc(MAXPATHLEN, KM_SLEEP); 128 (void) vt_getconsuser(link, MAXPATHLEN); 129 rval = (strcmp(link, dv->sdev_symlink) == 0) ? 130 SDEV_VTOR_VALID : SDEV_VTOR_STALE; 131 kmem_free(link, MAXPATHLEN); 132 return (rval); 133 } 134 135 if (devvt_str2minor(nm, &min) != 0) { 136 return (SDEV_VTOR_INVALID); 137 } 138 139 if (vt_minor_valid(min) == B_FALSE) 140 return (SDEV_VTOR_INVALID); 141 142 return (SDEV_VTOR_VALID); 143 } 144 145 /* 146 * This callback is invoked from devname_lookup_func() to create 147 * a entry when the node is not found in the cache. 148 */ 149 /*ARGSUSED*/ 150 static int 151 devvt_create_rvp(struct sdev_node *ddv, char *nm, 152 void **arg, cred_t *cred, void *whatever, char *whichever) 153 { 154 minor_t min; 155 major_t maj; 156 struct vattr *vap = (struct vattr *)arg; 157 158 if ((maj = vt_wc_attached()) == (major_t)-1) 159 return (SDEV_VTOR_INVALID); 160 161 if (strcmp(nm, DEVVT_ACTIVE_NAME) == 0) { 162 (void) vt_getactive((char *)*arg, MAXPATHLEN); 163 return (0); 164 } 165 166 if (strcmp(nm, DEVVT_CONSUSER_NAME) == 0) { 167 (void) vt_getconsuser((char *)*arg, MAXPATHLEN); 168 return (0); 169 } 170 if (devvt_str2minor(nm, &min) != 0) 171 return (-1); 172 173 if (vt_minor_valid(min) == B_FALSE) 174 return (-1); 175 176 *vap = devvt_vattr; 177 vap->va_rdev = makedevice(maj, min); 178 179 return (0); 180 } 181 182 /*ARGSUSED3*/ 183 static int 184 devvt_lookup(struct vnode *dvp, char *nm, struct vnode **vpp, 185 struct pathname *pnp, int flags, struct vnode *rdir, struct cred *cred, 186 caller_context_t *ct, int *direntflags, pathname_t *realpnp) 187 { 188 struct sdev_node *sdvp = VTOSDEV(dvp); 189 struct sdev_node *dv; 190 struct vnode *rvp = NULL; 191 int type, error; 192 193 if ((strcmp(nm, DEVVT_ACTIVE_NAME) == 0) || 194 (strcmp(nm, DEVVT_CONSUSER_NAME) == 0)) { 195 type = SDEV_VLINK; 196 } else { 197 type = SDEV_VATTR; 198 } 199 200 /* Give warlock a more clear call graph */ 201 #ifndef __lock_lint 202 error = devname_lookup_func(sdvp, nm, vpp, cred, 203 devvt_create_rvp, type); 204 #else 205 devvt_create_rvp(0, 0, 0, 0, 0, 0); 206 #endif 207 208 if (error == 0) { 209 switch ((*vpp)->v_type) { 210 case VCHR: 211 dv = VTOSDEV(VTOS(*vpp)->s_realvp); 212 ASSERT(VOP_REALVP(SDEVTOV(dv), &rvp, NULL) == ENOSYS); 213 break; 214 case VDIR: 215 case VLNK: 216 dv = VTOSDEV(*vpp); 217 break; 218 default: 219 cmn_err(CE_PANIC, "devvt_lookup: Unsupported node " 220 "type: %p: %d", (void *)(*vpp), (*vpp)->v_type); 221 break; 222 } 223 ASSERT(SDEV_HELD(dv)); 224 } 225 226 return (error); 227 } 228 229 static void 230 devvt_create_snode(struct sdev_node *ddv, char *nm, struct cred *cred, int type) 231 { 232 int error; 233 struct sdev_node *sdv = NULL; 234 struct vattr vattr; 235 struct vattr *vap = &vattr; 236 major_t maj; 237 minor_t min; 238 239 ASSERT(RW_WRITE_HELD(&ddv->sdev_contents)); 240 241 if ((maj = vt_wc_attached()) == (major_t)-1) 242 return; 243 244 if (strcmp(nm, DEVVT_ACTIVE_NAME) != 0 && 245 strcmp(nm, DEVVT_CONSUSER_NAME) != 0 && 246 devvt_str2minor(nm, &min) != 0) 247 return; 248 249 error = sdev_mknode(ddv, nm, &sdv, NULL, NULL, NULL, cred, SDEV_INIT); 250 if (error || !sdv) { 251 return; 252 } 253 254 mutex_enter(&sdv->sdev_lookup_lock); 255 SDEV_BLOCK_OTHERS(sdv, SDEV_LOOKUP); 256 mutex_exit(&sdv->sdev_lookup_lock); 257 258 if (type & SDEV_VATTR) { 259 *vap = devvt_vattr; 260 vap->va_rdev = makedevice(maj, min); 261 error = sdev_mknode(ddv, nm, &sdv, vap, NULL, 262 NULL, cred, SDEV_READY); 263 } else if (type & SDEV_VLINK) { 264 char *link = kmem_zalloc(MAXPATHLEN, KM_SLEEP); 265 266 (void) vt_getactive(link, MAXPATHLEN); 267 *vap = sdev_vattr_lnk; 268 vap->va_size = strlen(link); 269 error = sdev_mknode(ddv, nm, &sdv, vap, NULL, 270 (void *)link, cred, SDEV_READY); 271 272 kmem_free(link, MAXPATHLEN); 273 } 274 275 if (error != 0) { 276 SDEV_RELE(sdv); 277 return; 278 } 279 280 mutex_enter(&sdv->sdev_lookup_lock); 281 SDEV_UNBLOCK_OTHERS(sdv, SDEV_LOOKUP); 282 mutex_exit(&sdv->sdev_lookup_lock); 283 284 } 285 286 static void 287 devvt_rebuild_stale_link(struct sdev_node *ddv, struct sdev_node *dv) 288 { 289 char *link; 290 291 ASSERT(RW_WRITE_HELD(&ddv->sdev_contents)); 292 293 ASSERT((strcmp(dv->sdev_name, DEVVT_ACTIVE_NAME) == 0) || 294 (strcmp(dv->sdev_name, DEVVT_CONSUSER_NAME) == 0)); 295 296 link = kmem_zalloc(MAXPATHLEN, KM_SLEEP); 297 if (strcmp(dv->sdev_name, DEVVT_ACTIVE_NAME) == 0) { 298 (void) vt_getactive(link, MAXPATHLEN); 299 } else if (strcmp(dv->sdev_name, DEVVT_CONSUSER_NAME) == 0) { 300 (void) vt_getconsuser(link, MAXPATHLEN); 301 } 302 303 if (strcmp(link, dv->sdev_symlink) != 0) { 304 strfree(dv->sdev_symlink); 305 dv->sdev_symlink = strdup(link); 306 dv->sdev_attr->va_size = strlen(link); 307 } 308 kmem_free(link, MAXPATHLEN); 309 } 310 311 /* 312 * First step in refreshing directory contents. 313 * Remove each invalid entry and rebuild the link 314 * reference for each stale entry. 315 */ 316 static void 317 devvt_prunedir(struct sdev_node *ddv) 318 { 319 struct vnode *vp; 320 struct sdev_node *dv, *next = NULL; 321 int (*vtor)(struct sdev_node *) = NULL; 322 323 ASSERT(ddv->sdev_flags & SDEV_VTOR); 324 325 vtor = (int (*)(struct sdev_node *))sdev_get_vtor(ddv); 326 ASSERT(vtor); 327 328 for (dv = SDEV_FIRST_ENTRY(ddv); dv; dv = next) { 329 next = SDEV_NEXT_ENTRY(ddv, dv); 330 331 switch (vtor(dv)) { 332 case SDEV_VTOR_VALID: 333 break; 334 case SDEV_VTOR_SKIP: 335 break; 336 case SDEV_VTOR_INVALID: 337 vp = SDEVTOV(dv); 338 if (vp->v_count != 0) 339 break; 340 /* remove the cached node */ 341 SDEV_HOLD(dv); 342 (void) sdev_cache_update(ddv, &dv, 343 dv->sdev_name, SDEV_CACHE_DELETE); 344 SDEV_RELE(dv); 345 break; 346 case SDEV_VTOR_STALE: 347 devvt_rebuild_stale_link(ddv, dv); 348 break; 349 } 350 } 351 } 352 353 static void 354 devvt_cleandir(struct vnode *dvp, struct cred *cred) 355 { 356 struct sdev_node *sdvp = VTOSDEV(dvp); 357 struct sdev_node *dv, *next = NULL; 358 int min, cnt; 359 char found = 0; 360 361 mutex_enter(&vc_lock); 362 cnt = VC_INSTANCES_COUNT; 363 mutex_exit(&vc_lock); 364 365 if (rw_tryupgrade(&sdvp->sdev_contents) == 0) { 366 rw_exit(&sdvp->sdev_contents); 367 rw_enter(&sdvp->sdev_contents, RW_WRITER); 368 } 369 370 /* 1. prune invalid nodes and rebuild stale symlinks */ 371 devvt_prunedir(sdvp); 372 373 /* 2. create missing nodes */ 374 for (min = 0; min < cnt; min++) { 375 char nm[16]; 376 377 if (vt_minor_valid(min) == B_FALSE) 378 continue; 379 380 (void) snprintf(nm, sizeof (nm), "%d", min); 381 found = 0; 382 for (dv = SDEV_FIRST_ENTRY(sdvp); dv; dv = next) { 383 next = SDEV_NEXT_ENTRY(sdvp, dv); 384 385 /* validate only ready nodes */ 386 if (dv->sdev_state != SDEV_READY) 387 continue; 388 if (strcmp(nm, dv->sdev_name) == 0) { 389 found = 1; 390 break; 391 } 392 } 393 if (!found) { 394 devvt_create_snode(sdvp, nm, cred, SDEV_VATTR); 395 } 396 } 397 398 /* 3. create active link node and console user link node */ 399 found = 0; 400 for (dv = SDEV_FIRST_ENTRY(sdvp); dv; dv = next) { 401 next = SDEV_NEXT_ENTRY(sdvp, dv); 402 403 /* validate only ready nodes */ 404 if (dv->sdev_state != SDEV_READY) 405 continue; 406 if ((strcmp(dv->sdev_name, DEVVT_ACTIVE_NAME) == 0)) 407 found |= 0x01; 408 if ((strcmp(dv->sdev_name, DEVVT_CONSUSER_NAME) == 0)) 409 found |= 0x02; 410 411 if ((found & 0x01) && (found & 0x02)) 412 break; 413 } 414 if (!(found & 0x01)) 415 devvt_create_snode(sdvp, DEVVT_ACTIVE_NAME, cred, SDEV_VLINK); 416 if (!(found & 0x02)) 417 devvt_create_snode(sdvp, DEVVT_CONSUSER_NAME, cred, SDEV_VLINK); 418 419 #ifndef __lock_lint 420 rw_downgrade(&sdvp->sdev_contents); 421 #else 422 rw_exit(&sdvp->sdev_contents); 423 #endif 424 } 425 426 /*ARGSUSED4*/ 427 static int 428 devvt_readdir(struct vnode *dvp, struct uio *uiop, struct cred *cred, 429 int *eofp, caller_context_t *ct, int flags) 430 { 431 if (uiop->uio_offset == 0) { 432 devvt_cleandir(dvp, cred); 433 } 434 435 return (devname_readdir_func(dvp, uiop, cred, eofp, 0)); 436 } 437 438 /* 439 * We allow create to find existing nodes 440 * - if the node doesn't exist - EROFS 441 * - creating an existing dir read-only succeeds, otherwise EISDIR 442 * - exclusive creates fail - EEXIST 443 */ 444 /*ARGSUSED2*/ 445 static int 446 devvt_create(struct vnode *dvp, char *nm, struct vattr *vap, vcexcl_t excl, 447 int mode, struct vnode **vpp, struct cred *cred, int flag, 448 caller_context_t *ct, vsecattr_t *vsecp) 449 { 450 int error; 451 struct vnode *vp; 452 453 *vpp = NULL; 454 455 if ((error = devvt_lookup(dvp, nm, &vp, NULL, 0, NULL, cred, ct, NULL, 456 NULL)) != 0) { 457 if (error == ENOENT) 458 error = EROFS; 459 return (error); 460 } 461 462 if (excl == EXCL) 463 error = EEXIST; 464 else if (vp->v_type == VDIR && (mode & VWRITE)) 465 error = EISDIR; 466 else 467 error = VOP_ACCESS(vp, mode, 0, cred, ct); 468 469 if (error) { 470 VN_RELE(vp); 471 } else 472 *vpp = vp; 473 474 return (error); 475 } 476 477 const fs_operation_def_t devvt_vnodeops_tbl[] = { 478 VOPNAME_READDIR, { .vop_readdir = devvt_readdir }, 479 VOPNAME_LOOKUP, { .vop_lookup = devvt_lookup }, 480 VOPNAME_CREATE, { .vop_create = devvt_create }, 481 VOPNAME_REMOVE, { .error = fs_nosys }, 482 VOPNAME_MKDIR, { .error = fs_nosys }, 483 VOPNAME_RMDIR, { .error = fs_nosys }, 484 VOPNAME_SYMLINK, { .error = fs_nosys }, 485 VOPNAME_SETSECATTR, { .error = fs_nosys }, 486 NULL, NULL 487 }; 488