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 2008 Sun Microsystems, Inc. All rights reserved. 23 * Use is subject to license terms. 24 */ 25 26 /* 27 * vnode ops for the /dev/vt directory 28 */ 29 30 #include <sys/types.h> 31 #include <sys/param.h> 32 #include <sys/sysmacros.h> 33 #include <sys/sunndi.h> 34 #include <fs/fs_subr.h> 35 #include <sys/fs/dv_node.h> 36 #include <sys/fs/sdev_impl.h> 37 #include <sys/policy.h> 38 #include <sys/stat.h> 39 #include <sys/vfs_opreg.h> 40 #include <sys/tty.h> 41 #include <sys/vt_impl.h> 42 #include <sys/note.h> 43 44 /* warlock in this file only cares about variables shared by vt and devfs */ 45 _NOTE(SCHEME_PROTECTS_DATA("Do not care", sdev_node vattr vnode)) 46 47 #define DEVVT_UID_DEFAULT SDEV_UID_DEFAULT 48 #define DEVVT_GID_DEFAULT (0) 49 #define DEVVT_DEVMODE_DEFAULT (0600) 50 #define DEVVT_ACTIVE_NAME "active" 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 /*ARGSUSED*/ 92 int 93 devvt_validate(struct sdev_node *dv) 94 { 95 minor_t min; 96 char *nm = dv->sdev_name; 97 98 ASSERT(!(dv->sdev_flags & SDEV_STALE)); 99 ASSERT(dv->sdev_state == SDEV_READY); 100 101 /* validate only READY nodes */ 102 if (dv->sdev_state != SDEV_READY) { 103 sdcmn_err(("dev fs: skipping: node not ready %s(%p)", 104 nm, (void *)dv)); 105 return (SDEV_VTOR_SKIP); 106 } 107 108 if (vt_wc_attached() == (major_t)-1) 109 return (SDEV_VTOR_INVALID); 110 111 if (strcmp(nm, DEVVT_ACTIVE_NAME) == 0) { 112 char *link = kmem_zalloc(MAXPATHLEN, KM_SLEEP); 113 114 (void) vt_getactive(link, MAXPATHLEN); 115 if (strcmp(link, dv->sdev_symlink) != 0) { 116 kmem_free(dv->sdev_symlink, 117 strlen(dv->sdev_symlink) + 1); 118 dv->sdev_symlink = i_ddi_strdup(link, KM_SLEEP); 119 dv->sdev_attr->va_size = strlen(link); 120 } 121 kmem_free(link, MAXPATHLEN); 122 return (SDEV_VTOR_VALID); 123 } else if (devvt_str2minor(nm, &min) != 0) { 124 return (SDEV_VTOR_INVALID); 125 } 126 127 if (vt_minor_valid(min) == B_FALSE) 128 return (SDEV_VTOR_INVALID); 129 130 return (SDEV_VTOR_VALID); 131 } 132 133 /* 134 * This callback is invoked from devname_lookup_func() to create 135 * a entry when the node is not found in the cache. 136 */ 137 /*ARGSUSED*/ 138 static int 139 devvt_create_rvp(struct sdev_node *ddv, char *nm, 140 void **arg, cred_t *cred, void *whatever, char *whichever) 141 { 142 minor_t min; 143 major_t maj; 144 struct vattr *vap = (struct vattr *)arg; 145 146 if ((maj = vt_wc_attached()) == (major_t)-1) 147 return (SDEV_VTOR_INVALID); 148 149 if (strcmp(nm, DEVVT_ACTIVE_NAME) == 0) { 150 (void) vt_getactive((char *)*arg, MAXPATHLEN); 151 return (0); 152 } 153 154 if (devvt_str2minor(nm, &min) != 0) 155 return (-1); 156 157 if (vt_minor_valid(min) == B_FALSE) 158 return (-1); 159 160 *vap = devvt_vattr; 161 vap->va_rdev = makedevice(maj, min); 162 163 return (0); 164 } 165 166 /*ARGSUSED3*/ 167 static int 168 devvt_lookup(struct vnode *dvp, char *nm, struct vnode **vpp, 169 struct pathname *pnp, int flags, struct vnode *rdir, struct cred *cred, 170 caller_context_t *ct, int *direntflags, pathname_t *realpnp) 171 { 172 struct sdev_node *sdvp = VTOSDEV(dvp); 173 struct sdev_node *dv; 174 struct vnode *rvp = NULL; 175 int type, error; 176 177 if (strcmp(nm, DEVVT_ACTIVE_NAME) == 0) { 178 type = SDEV_VLINK; 179 } else { 180 type = SDEV_VATTR; 181 } 182 183 /* Give warlock a more clear call graph */ 184 #ifndef __lock_lint 185 error = devname_lookup_func(sdvp, nm, vpp, cred, 186 devvt_create_rvp, type); 187 #else 188 devvt_create_rvp(0, 0, 0, 0, 0, 0); 189 #endif 190 191 if (error == 0) { 192 switch ((*vpp)->v_type) { 193 case VCHR: 194 dv = VTOSDEV(VTOS(*vpp)->s_realvp); 195 ASSERT(VOP_REALVP(SDEVTOV(dv), &rvp, NULL) == ENOSYS); 196 break; 197 case VDIR: 198 case VLNK: 199 dv = VTOSDEV(*vpp); 200 break; 201 default: 202 cmn_err(CE_PANIC, "devvt_lookup: Unsupported node " 203 "type: %p: %d", (void *)(*vpp), (*vpp)->v_type); 204 break; 205 } 206 ASSERT(SDEV_HELD(dv)); 207 } 208 209 return (error); 210 } 211 212 static void 213 devvt_create_snode(struct sdev_node *ddv, char *nm, struct cred *cred, int type) 214 { 215 int error; 216 struct sdev_node *sdv = NULL; 217 struct vattr *vap = NULL; 218 major_t maj; 219 minor_t min; 220 221 if ((maj = vt_wc_attached()) == (major_t)-1) 222 return; 223 224 if (strcmp(nm, DEVVT_ACTIVE_NAME) != 0 && 225 devvt_str2minor(nm, &min) != 0) 226 return; 227 228 error = sdev_mknode(ddv, nm, &sdv, NULL, NULL, NULL, cred, SDEV_INIT); 229 if (error || !sdv) { 230 return; 231 } 232 233 mutex_enter(&sdv->sdev_lookup_lock); 234 SDEV_BLOCK_OTHERS(sdv, SDEV_LOOKUP); 235 mutex_exit(&sdv->sdev_lookup_lock); 236 237 if (type & SDEV_VATTR) { 238 vap = &devvt_vattr; 239 vap->va_rdev = makedevice(maj, min); 240 error = sdev_mknode(ddv, nm, &sdv, vap, NULL, 241 NULL, cred, SDEV_READY); 242 } else if (type & SDEV_VLINK) { 243 char *link = kmem_zalloc(MAXPATHLEN, KM_SLEEP); 244 245 (void) vt_getactive(link, MAXPATHLEN); 246 vap = &sdev_vattr_lnk; 247 vap->va_size = strlen(link); 248 error = sdev_mknode(ddv, nm, &sdv, vap, NULL, 249 (void *)link, cred, SDEV_READY); 250 251 kmem_free(link, MAXPATHLEN); 252 } 253 254 mutex_enter(&sdv->sdev_lookup_lock); 255 SDEV_UNBLOCK_OTHERS(sdv, SDEV_LOOKUP); 256 mutex_exit(&sdv->sdev_lookup_lock); 257 258 } 259 260 static void 261 devvt_prunedir(struct sdev_node *ddv) 262 { 263 struct vnode *vp; 264 struct sdev_node *dv, *next = NULL; 265 int (*vtor)(struct sdev_node *) = NULL; 266 267 ASSERT(ddv->sdev_flags & SDEV_VTOR); 268 269 vtor = (int (*)(struct sdev_node *))sdev_get_vtor(ddv); 270 ASSERT(vtor); 271 272 for (dv = SDEV_FIRST_ENTRY(ddv); dv; dv = next) { 273 next = SDEV_NEXT_ENTRY(ddv, dv); 274 275 /* skip stale nodes */ 276 if (dv->sdev_flags & SDEV_STALE) 277 continue; 278 279 /* validate and prune only ready nodes */ 280 if (dv->sdev_state != SDEV_READY) 281 continue; 282 283 switch (vtor(dv)) { 284 case SDEV_VTOR_VALID: 285 case SDEV_VTOR_SKIP: 286 continue; 287 case SDEV_VTOR_INVALID: 288 case SDEV_VTOR_STALE: 289 sdcmn_err7(("destroy invalid " 290 "node: %s(%p)\n", dv->sdev_name, (void *)dv)); 291 break; 292 } 293 vp = SDEVTOV(dv); 294 if (vp->v_count > 0) 295 continue; 296 SDEV_HOLD(dv); 297 /* remove the cache node */ 298 (void) sdev_cache_update(ddv, &dv, dv->sdev_name, 299 SDEV_CACHE_DELETE); 300 } 301 } 302 303 static void 304 devvt_cleandir(struct vnode *dvp, struct cred *cred) 305 { 306 struct sdev_node *sdvp = VTOSDEV(dvp); 307 struct sdev_node *dv, *next = NULL; 308 int min, cnt; 309 int found = 0; 310 311 mutex_enter(&vc_lock); 312 cnt = VC_INSTANCES_COUNT; 313 mutex_exit(&vc_lock); 314 315 /* We have to fool warlock this way, otherwise it will complain */ 316 #ifndef __lock_lint 317 if (rw_tryupgrade(&sdvp->sdev_contents) == NULL) { 318 rw_exit(&sdvp->sdev_contents); 319 rw_enter(&sdvp->sdev_contents, RW_WRITER); 320 } 321 #else 322 rw_enter(&sdvp->sdev_contents, RW_WRITER); 323 #endif 324 325 /* 1. create missed nodes */ 326 for (min = 0; min < cnt; min++) { 327 char nm[16]; 328 329 if (vt_minor_valid(min) == B_FALSE) 330 continue; 331 332 (void) snprintf(nm, sizeof (nm), "%d", min); 333 found = 0; 334 for (dv = SDEV_FIRST_ENTRY(sdvp); dv; dv = next) { 335 next = SDEV_NEXT_ENTRY(sdvp, dv); 336 337 /* skip stale nodes */ 338 if (dv->sdev_flags & SDEV_STALE) 339 continue; 340 /* validate and prune only ready nodes */ 341 if (dv->sdev_state != SDEV_READY) 342 continue; 343 if (strcmp(nm, dv->sdev_name) == 0) { 344 found = 1; 345 break; 346 } 347 } 348 if (!found) { 349 devvt_create_snode(sdvp, nm, cred, SDEV_VATTR); 350 } 351 } 352 353 /* 2. create active link node */ 354 found = 0; 355 for (dv = SDEV_FIRST_ENTRY(sdvp); dv; dv = next) { 356 next = SDEV_NEXT_ENTRY(sdvp, dv); 357 358 /* skip stale nodes */ 359 if (dv->sdev_flags & SDEV_STALE) 360 continue; 361 /* validate and prune only ready nodes */ 362 if (dv->sdev_state != SDEV_READY) 363 continue; 364 if ((strcmp(dv->sdev_name, DEVVT_ACTIVE_NAME) == NULL)) { 365 found = 1; 366 break; 367 } 368 } 369 if (!found) 370 devvt_create_snode(sdvp, DEVVT_ACTIVE_NAME, cred, SDEV_VLINK); 371 372 /* 3. cleanup invalid nodes */ 373 devvt_prunedir(sdvp); 374 375 #ifndef __lock_lint 376 rw_downgrade(&sdvp->sdev_contents); 377 #else 378 rw_exit(&sdvp->sdev_contents); 379 #endif 380 } 381 382 /*ARGSUSED4*/ 383 static int 384 devvt_readdir(struct vnode *dvp, struct uio *uiop, struct cred *cred, 385 int *eofp, caller_context_t *ct, int flags) 386 { 387 if (uiop->uio_offset == 0) { 388 devvt_cleandir(dvp, cred); 389 } 390 391 return (devname_readdir_func(dvp, uiop, cred, eofp, 0)); 392 } 393 394 /* 395 * We allow create to find existing nodes 396 * - if the node doesn't exist - EROFS 397 * - creating an existing dir read-only succeeds, otherwise EISDIR 398 * - exclusive creates fail - EEXIST 399 */ 400 /*ARGSUSED2*/ 401 static int 402 devvt_create(struct vnode *dvp, char *nm, struct vattr *vap, vcexcl_t excl, 403 int mode, struct vnode **vpp, struct cred *cred, int flag, 404 caller_context_t *ct, vsecattr_t *vsecp) 405 { 406 int error; 407 struct vnode *vp; 408 409 *vpp = NULL; 410 411 if ((error = devvt_lookup(dvp, nm, &vp, NULL, 0, NULL, cred, ct, NULL, 412 NULL)) != 0) { 413 if (error == ENOENT) 414 error = EROFS; 415 return (error); 416 } 417 418 if (excl == EXCL) 419 error = EEXIST; 420 else if (vp->v_type == VDIR && (mode & VWRITE)) 421 error = EISDIR; 422 else 423 error = VOP_ACCESS(vp, mode, 0, cred, ct); 424 425 if (error) { 426 VN_RELE(vp); 427 } else 428 *vpp = vp; 429 430 return (error); 431 } 432 433 const fs_operation_def_t devvt_vnodeops_tbl[] = { 434 VOPNAME_READDIR, { .vop_readdir = devvt_readdir }, 435 VOPNAME_LOOKUP, { .vop_lookup = devvt_lookup }, 436 VOPNAME_CREATE, { .vop_create = devvt_create }, 437 VOPNAME_REMOVE, { .error = fs_nosys }, 438 VOPNAME_MKDIR, { .error = fs_nosys }, 439 VOPNAME_RMDIR, { .error = fs_nosys }, 440 VOPNAME_SYMLINK, { .error = fs_nosys }, 441 VOPNAME_SETSECATTR, { .error = fs_nosys }, 442 NULL, NULL 443 }; 444