kernfs_vnops.c revision 1.160.4.2
1 /* $NetBSD: kernfs_vnops.c,v 1.160.4.2 2020/02/12 19:59:22 martin 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 * Jan-Simon Pendry. 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 * @(#)kernfs_vnops.c 8.15 (Berkeley) 5/21/95 35 */ 36 37 /* 38 * Kernel parameter filesystem (/kern) 39 */ 40 41 #include <sys/cdefs.h> 42 __KERNEL_RCSID(0, "$NetBSD: kernfs_vnops.c,v 1.160.4.2 2020/02/12 19:59:22 martin Exp $"); 43 44 #include <sys/param.h> 45 #include <sys/systm.h> 46 #include <sys/kernel.h> 47 #include <sys/vmmeter.h> 48 #include <sys/time.h> 49 #include <sys/proc.h> 50 #include <sys/vnode.h> 51 #include <sys/malloc.h> 52 #include <sys/file.h> 53 #include <sys/stat.h> 54 #include <sys/mount.h> 55 #include <sys/namei.h> 56 #include <sys/buf.h> 57 #include <sys/dirent.h> 58 #include <sys/msgbuf.h> 59 60 #include <miscfs/genfs/genfs.h> 61 #include <miscfs/kernfs/kernfs.h> 62 #include <miscfs/specfs/specdev.h> 63 64 #include <uvm/uvm_extern.h> 65 66 #define KSTRING 256 /* Largest I/O available via this filesystem */ 67 #define UIO_MX 32 68 69 #define READ_MODE (S_IRUSR|S_IRGRP|S_IROTH) 70 #define WRITE_MODE (S_IWUSR|S_IRUSR|S_IRGRP|S_IROTH) 71 #define UREAD_MODE (S_IRUSR) 72 #define DIR_MODE (S_IRUSR|S_IXUSR|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH) 73 #define UDIR_MODE (S_IRUSR|S_IXUSR) 74 75 #define N(s) sizeof(s)-1, s 76 const struct kern_target kern_targets[] = { 77 /* NOTE: The name must be less than UIO_MX-16 chars in length */ 78 /* name data tag type ro/rw */ 79 { DT_DIR, N("."), 0, KFSkern, VDIR, DIR_MODE }, 80 { DT_DIR, N(".."), 0, KFSroot, VDIR, DIR_MODE }, 81 { DT_REG, N("boottime"), &boottime.tv_sec, KFSint, VREG, READ_MODE }, 82 /* XXXUNCONST */ 83 { DT_REG, N("copyright"), __UNCONST(copyright), 84 KFSstring, VREG, READ_MODE }, 85 { DT_REG, N("hostname"), 0, KFShostname, VREG, WRITE_MODE }, 86 { DT_REG, N("hz"), &hz, KFSint, VREG, READ_MODE }, 87 { DT_REG, N("loadavg"), 0, KFSavenrun, VREG, READ_MODE }, 88 { DT_REG, N("msgbuf"), 0, KFSmsgbuf, VREG, READ_MODE }, 89 { DT_REG, N("pagesize"), &uvmexp.pagesize, KFSint, VREG, READ_MODE }, 90 { DT_REG, N("physmem"), &physmem, KFSint, VREG, READ_MODE }, 91 #if 0 92 { DT_DIR, N("root"), 0, KFSnull, VDIR, DIR_MODE }, 93 #endif 94 { DT_BLK, N("rootdev"), &rootdev, KFSdevice, VBLK, READ_MODE }, 95 { DT_CHR, N("rrootdev"), &rrootdev, KFSdevice, VCHR, READ_MODE }, 96 { DT_REG, N("time"), 0, KFStime, VREG, READ_MODE }, 97 /* XXXUNCONST */ 98 { DT_REG, N("version"), __UNCONST(version), 99 KFSstring, VREG, READ_MODE }, 100 }; 101 const struct kern_target subdir_targets[] = { 102 /* NOTE: The name must be less than UIO_MX-16 chars in length */ 103 /* name data tag type ro/rw */ 104 { DT_DIR, N("."), 0, KFSsubdir, VDIR, DIR_MODE }, 105 { DT_DIR, N(".."), 0, KFSkern, VDIR, DIR_MODE }, 106 }; 107 #undef N 108 SIMPLEQ_HEAD(,dyn_kern_target) dyn_kern_targets = 109 SIMPLEQ_HEAD_INITIALIZER(dyn_kern_targets); 110 int nkern_targets = sizeof(kern_targets) / sizeof(kern_targets[0]); 111 const int static_nkern_targets = sizeof(kern_targets) / sizeof(kern_targets[0]); 112 int nkern_dirs = 2; 113 114 int kernfs_try_fileop(kfstype, kfsfileop, void *, int); 115 int kernfs_try_xread(kfstype, const struct kernfs_node *, char **, 116 size_t, int); 117 int kernfs_try_xwrite(kfstype, const struct kernfs_node *, char *, 118 size_t, int); 119 120 static int kernfs_default_xread(void *v); 121 static int kernfs_default_xwrite(void *v); 122 static int kernfs_default_fileop_getattr(void *); 123 124 /* must include all fileop's */ 125 const struct kernfs_fileop kernfs_default_fileops[] = { 126 { .kf_fileop = KERNFS_XREAD }, 127 { .kf_fileop = KERNFS_XWRITE }, 128 { .kf_fileop = KERNFS_FILEOP_OPEN }, 129 { .kf_fileop = KERNFS_FILEOP_GETATTR, 130 .kf_vop = kernfs_default_fileop_getattr }, 131 { .kf_fileop = KERNFS_FILEOP_IOCTL }, 132 { .kf_fileop = KERNFS_FILEOP_CLOSE }, 133 { .kf_fileop = KERNFS_FILEOP_READ, 134 .kf_vop = kernfs_default_xread }, 135 { .kf_fileop = KERNFS_FILEOP_WRITE, 136 .kf_vop = kernfs_default_xwrite }, 137 }; 138 139 int kernfs_lookup(void *); 140 #define kernfs_create genfs_eopnotsupp 141 #define kernfs_mknod genfs_eopnotsupp 142 int kernfs_open(void *); 143 int kernfs_close(void *); 144 int kernfs_access(void *); 145 int kernfs_getattr(void *); 146 int kernfs_setattr(void *); 147 int kernfs_read(void *); 148 int kernfs_write(void *); 149 #define kernfs_fcntl genfs_fcntl 150 int kernfs_ioctl(void *); 151 #define kernfs_poll genfs_poll 152 #define kernfs_revoke genfs_revoke 153 #define kernfs_fsync genfs_nullop 154 #define kernfs_seek genfs_nullop 155 #define kernfs_remove genfs_eopnotsupp 156 int kernfs_link(void *); 157 #define kernfs_rename genfs_eopnotsupp 158 #define kernfs_mkdir genfs_eopnotsupp 159 #define kernfs_rmdir genfs_eopnotsupp 160 int kernfs_symlink(void *); 161 int kernfs_readdir(void *); 162 #define kernfs_readlink genfs_eopnotsupp 163 #define kernfs_abortop genfs_abortop 164 int kernfs_inactive(void *); 165 int kernfs_reclaim(void *); 166 #define kernfs_lock genfs_lock 167 #define kernfs_unlock genfs_unlock 168 #define kernfs_bmap genfs_badop 169 #define kernfs_strategy genfs_badop 170 int kernfs_print(void *); 171 #define kernfs_islocked genfs_islocked 172 int kernfs_pathconf(void *); 173 #define kernfs_advlock genfs_einval 174 #define kernfs_bwrite genfs_eopnotsupp 175 int kernfs_getpages(void *); 176 #define kernfs_putpages genfs_putpages 177 178 static int kernfs_xread(struct kernfs_node *, int, char **, 179 size_t, size_t *); 180 static int kernfs_xwrite(const struct kernfs_node *, char *, size_t); 181 182 int (**kernfs_vnodeop_p)(void *); 183 const struct vnodeopv_entry_desc kernfs_vnodeop_entries[] = { 184 { &vop_default_desc, vn_default_error }, 185 { &vop_lookup_desc, kernfs_lookup }, /* lookup */ 186 { &vop_create_desc, kernfs_create }, /* create */ 187 { &vop_mknod_desc, kernfs_mknod }, /* mknod */ 188 { &vop_open_desc, kernfs_open }, /* open */ 189 { &vop_close_desc, kernfs_close }, /* close */ 190 { &vop_access_desc, kernfs_access }, /* access */ 191 { &vop_getattr_desc, kernfs_getattr }, /* getattr */ 192 { &vop_setattr_desc, kernfs_setattr }, /* setattr */ 193 { &vop_read_desc, kernfs_read }, /* read */ 194 { &vop_write_desc, kernfs_write }, /* write */ 195 { &vop_fallocate_desc, genfs_eopnotsupp }, /* fallocate */ 196 { &vop_fdiscard_desc, genfs_eopnotsupp }, /* fdiscard */ 197 { &vop_fcntl_desc, kernfs_fcntl }, /* fcntl */ 198 { &vop_ioctl_desc, kernfs_ioctl }, /* ioctl */ 199 { &vop_poll_desc, kernfs_poll }, /* poll */ 200 { &vop_revoke_desc, kernfs_revoke }, /* revoke */ 201 { &vop_fsync_desc, kernfs_fsync }, /* fsync */ 202 { &vop_seek_desc, kernfs_seek }, /* seek */ 203 { &vop_remove_desc, kernfs_remove }, /* remove */ 204 { &vop_link_desc, kernfs_link }, /* link */ 205 { &vop_rename_desc, kernfs_rename }, /* rename */ 206 { &vop_mkdir_desc, kernfs_mkdir }, /* mkdir */ 207 { &vop_rmdir_desc, kernfs_rmdir }, /* rmdir */ 208 { &vop_symlink_desc, kernfs_symlink }, /* symlink */ 209 { &vop_readdir_desc, kernfs_readdir }, /* readdir */ 210 { &vop_readlink_desc, kernfs_readlink }, /* readlink */ 211 { &vop_abortop_desc, kernfs_abortop }, /* abortop */ 212 { &vop_inactive_desc, kernfs_inactive }, /* inactive */ 213 { &vop_reclaim_desc, kernfs_reclaim }, /* reclaim */ 214 { &vop_lock_desc, kernfs_lock }, /* lock */ 215 { &vop_unlock_desc, kernfs_unlock }, /* unlock */ 216 { &vop_bmap_desc, kernfs_bmap }, /* bmap */ 217 { &vop_strategy_desc, kernfs_strategy }, /* strategy */ 218 { &vop_print_desc, kernfs_print }, /* print */ 219 { &vop_islocked_desc, kernfs_islocked }, /* islocked */ 220 { &vop_pathconf_desc, kernfs_pathconf }, /* pathconf */ 221 { &vop_advlock_desc, kernfs_advlock }, /* advlock */ 222 { &vop_bwrite_desc, kernfs_bwrite }, /* bwrite */ 223 { &vop_getpages_desc, kernfs_getpages }, /* getpages */ 224 { &vop_putpages_desc, kernfs_putpages }, /* putpages */ 225 { NULL, NULL } 226 }; 227 const struct vnodeopv_desc kernfs_vnodeop_opv_desc = 228 { &kernfs_vnodeop_p, kernfs_vnodeop_entries }; 229 230 int (**kernfs_specop_p)(void *); 231 const struct vnodeopv_entry_desc kernfs_specop_entries[] = { 232 { &vop_default_desc, vn_default_error }, 233 { &vop_lookup_desc, spec_lookup }, /* lookup */ 234 { &vop_create_desc, spec_create }, /* create */ 235 { &vop_mknod_desc, spec_mknod }, /* mknod */ 236 { &vop_open_desc, spec_open }, /* open */ 237 { &vop_close_desc, spec_close }, /* close */ 238 { &vop_access_desc, kernfs_access }, /* access */ 239 { &vop_getattr_desc, kernfs_getattr }, /* getattr */ 240 { &vop_setattr_desc, kernfs_setattr }, /* setattr */ 241 { &vop_read_desc, spec_read }, /* read */ 242 { &vop_write_desc, spec_write }, /* write */ 243 { &vop_fallocate_desc, spec_fallocate }, /* fallocate */ 244 { &vop_fdiscard_desc, spec_fdiscard }, /* fdiscard */ 245 { &vop_fcntl_desc, spec_fcntl }, /* fcntl */ 246 { &vop_ioctl_desc, spec_ioctl }, /* ioctl */ 247 { &vop_poll_desc, spec_poll }, /* poll */ 248 { &vop_revoke_desc, spec_revoke }, /* revoke */ 249 { &vop_fsync_desc, spec_fsync }, /* fsync */ 250 { &vop_seek_desc, spec_seek }, /* seek */ 251 { &vop_remove_desc, spec_remove }, /* remove */ 252 { &vop_link_desc, spec_link }, /* link */ 253 { &vop_rename_desc, spec_rename }, /* rename */ 254 { &vop_mkdir_desc, spec_mkdir }, /* mkdir */ 255 { &vop_rmdir_desc, spec_rmdir }, /* rmdir */ 256 { &vop_symlink_desc, spec_symlink }, /* symlink */ 257 { &vop_readdir_desc, spec_readdir }, /* readdir */ 258 { &vop_readlink_desc, spec_readlink }, /* readlink */ 259 { &vop_abortop_desc, spec_abortop }, /* abortop */ 260 { &vop_inactive_desc, kernfs_inactive }, /* inactive */ 261 { &vop_reclaim_desc, kernfs_reclaim }, /* reclaim */ 262 { &vop_lock_desc, kernfs_lock }, /* lock */ 263 { &vop_unlock_desc, kernfs_unlock }, /* unlock */ 264 { &vop_bmap_desc, spec_bmap }, /* bmap */ 265 { &vop_strategy_desc, spec_strategy }, /* strategy */ 266 { &vop_print_desc, kernfs_print }, /* print */ 267 { &vop_islocked_desc, kernfs_islocked }, /* islocked */ 268 { &vop_pathconf_desc, spec_pathconf }, /* pathconf */ 269 { &vop_advlock_desc, spec_advlock }, /* advlock */ 270 { &vop_bwrite_desc, spec_bwrite }, /* bwrite */ 271 { &vop_getpages_desc, spec_getpages }, /* getpages */ 272 { &vop_putpages_desc, spec_putpages }, /* putpages */ 273 { NULL, NULL } 274 }; 275 const struct vnodeopv_desc kernfs_specop_opv_desc = 276 { &kernfs_specop_p, kernfs_specop_entries }; 277 278 static inline int 279 kernfs_fileop_compare(struct kernfs_fileop *a, struct kernfs_fileop *b) 280 { 281 if (a->kf_type < b->kf_type) 282 return -1; 283 if (a->kf_type > b->kf_type) 284 return 1; 285 if (a->kf_fileop < b->kf_fileop) 286 return -1; 287 if (a->kf_fileop > b->kf_fileop) 288 return 1; 289 return (0); 290 } 291 292 SPLAY_HEAD(kfsfileoptree, kernfs_fileop) kfsfileoptree = 293 SPLAY_INITIALIZER(kfsfileoptree); 294 SPLAY_PROTOTYPE(kfsfileoptree, kernfs_fileop, kf_node, kernfs_fileop_compare); 295 SPLAY_GENERATE(kfsfileoptree, kernfs_fileop, kf_node, kernfs_fileop_compare); 296 297 kfstype 298 kernfs_alloctype(int nkf, const struct kernfs_fileop *kf) 299 { 300 static u_char nextfreetype = KFSlasttype; 301 struct kernfs_fileop *dkf, *fkf, skf; 302 int i; 303 304 /* XXX need to keep track of dkf's memory if we support 305 deallocating types */ 306 dkf = malloc(sizeof(kernfs_default_fileops), M_TEMP, M_WAITOK); 307 memcpy(dkf, kernfs_default_fileops, sizeof(kernfs_default_fileops)); 308 309 for (i = 0; i < sizeof(kernfs_default_fileops) / 310 sizeof(kernfs_default_fileops[0]); i++) { 311 dkf[i].kf_type = nextfreetype; 312 SPLAY_INSERT(kfsfileoptree, &kfsfileoptree, &dkf[i]); 313 } 314 315 for (i = 0; i < nkf; i++) { 316 skf.kf_type = nextfreetype; 317 skf.kf_fileop = kf[i].kf_fileop; 318 if ((fkf = SPLAY_FIND(kfsfileoptree, &kfsfileoptree, &skf))) 319 fkf->kf_vop = kf[i].kf_vop; 320 } 321 322 return nextfreetype++; 323 } 324 325 int 326 kernfs_try_fileop(kfstype type, kfsfileop fileop, void *v, int error) 327 { 328 struct kernfs_fileop *kf, skf; 329 330 skf.kf_type = type; 331 skf.kf_fileop = fileop; 332 if ((kf = SPLAY_FIND(kfsfileoptree, &kfsfileoptree, &skf))) 333 if (kf->kf_vop) 334 return kf->kf_vop(v); 335 return error; 336 } 337 338 int 339 kernfs_try_xread(kfstype type, const struct kernfs_node *kfs, char **bfp, 340 size_t len, int error) 341 { 342 struct kernfs_fileop *kf, skf; 343 344 skf.kf_type = type; 345 skf.kf_fileop = KERNFS_XREAD; 346 if ((kf = SPLAY_FIND(kfsfileoptree, &kfsfileoptree, &skf))) 347 if (kf->kf_xread) 348 return kf->kf_xread(kfs, bfp, len); 349 return error; 350 } 351 352 int 353 kernfs_try_xwrite(kfstype type, const struct kernfs_node *kfs, char *bf, 354 size_t len, int error) 355 { 356 struct kernfs_fileop *kf, skf; 357 358 skf.kf_type = type; 359 skf.kf_fileop = KERNFS_XWRITE; 360 if ((kf = SPLAY_FIND(kfsfileoptree, &kfsfileoptree, &skf))) 361 if (kf->kf_xwrite) 362 return kf->kf_xwrite(kfs, bf, len); 363 return error; 364 } 365 366 int 367 kernfs_addentry(kernfs_parentdir_t *pkt, kernfs_entry_t *dkt) 368 { 369 struct kernfs_subdir *ks, *parent; 370 371 if (pkt == NULL) { 372 SIMPLEQ_INSERT_TAIL(&dyn_kern_targets, dkt, dkt_queue); 373 nkern_targets++; 374 if (dkt->dkt_kt.kt_vtype == VDIR) 375 nkern_dirs++; 376 } else { 377 parent = (struct kernfs_subdir *)pkt->kt_data; 378 SIMPLEQ_INSERT_TAIL(&parent->ks_entries, dkt, dkt_queue); 379 parent->ks_nentries++; 380 if (dkt->dkt_kt.kt_vtype == VDIR) 381 parent->ks_dirs++; 382 } 383 if (dkt->dkt_kt.kt_vtype == VDIR && dkt->dkt_kt.kt_data == NULL) { 384 ks = malloc(sizeof(struct kernfs_subdir), 385 M_TEMP, M_WAITOK); 386 SIMPLEQ_INIT(&ks->ks_entries); 387 ks->ks_nentries = 2; /* . and .. */ 388 ks->ks_dirs = 2; 389 ks->ks_parent = pkt ? pkt : &kern_targets[0]; 390 dkt->dkt_kt.kt_data = ks; 391 } 392 return 0; 393 } 394 395 static int 396 kernfs_xread(struct kernfs_node *kfs, int off, char **bufp, size_t len, size_t *wrlen) 397 { 398 const struct kern_target *kt; 399 int err; 400 401 kt = kfs->kfs_kt; 402 403 switch (kfs->kfs_type) { 404 case KFStime: { 405 struct timeval tv; 406 407 microtime(&tv); 408 snprintf(*bufp, len, "%lld %ld\n", (long long)tv.tv_sec, 409 (long)tv.tv_usec); 410 break; 411 } 412 413 case KFSint: { 414 int *ip = kt->kt_data; 415 416 snprintf(*bufp, len, "%d\n", *ip); 417 break; 418 } 419 420 case KFSstring: { 421 char *cp = kt->kt_data; 422 423 *bufp = cp; 424 break; 425 } 426 427 case KFSmsgbuf: { 428 long n; 429 430 /* 431 * deal with cases where the message buffer has 432 * become corrupted. 433 */ 434 if (!logenabled(msgbufp)) { 435 msgbufenabled = 0; 436 return (ENXIO); 437 } 438 439 /* 440 * Note that reads of /kern/msgbuf won't necessarily yield 441 * consistent results, if the message buffer is modified 442 * while the read is in progress. The worst that can happen 443 * is that incorrect data will be read. There's no way 444 * that this can crash the system unless the values in the 445 * message buffer header are corrupted, but that'll cause 446 * the system to die anyway. 447 */ 448 if (off >= msgbufp->msg_bufs) { 449 *wrlen = 0; 450 return (0); 451 } 452 n = msgbufp->msg_bufx + off; 453 if (n >= msgbufp->msg_bufs) 454 n -= msgbufp->msg_bufs; 455 len = uimin(msgbufp->msg_bufs - n, msgbufp->msg_bufs - off); 456 *bufp = msgbufp->msg_bufc + n; 457 *wrlen = len; 458 return (0); 459 } 460 461 case KFShostname: { 462 char *cp = hostname; 463 size_t xlen = hostnamelen; 464 465 if (xlen >= (len - 2)) 466 return (EINVAL); 467 468 memcpy(*bufp, cp, xlen); 469 (*bufp)[xlen] = '\n'; 470 (*bufp)[xlen+1] = '\0'; 471 break; 472 } 473 474 case KFSavenrun: 475 averunnable.fscale = FSCALE; 476 snprintf(*bufp, len, "%d %d %d %ld\n", 477 averunnable.ldavg[0], averunnable.ldavg[1], 478 averunnable.ldavg[2], averunnable.fscale); 479 break; 480 481 default: 482 err = kernfs_try_xread(kfs->kfs_type, kfs, bufp, len, 483 EOPNOTSUPP); 484 if (err) 485 return err; 486 } 487 488 len = strlen(*bufp); 489 if (len <= off) 490 *wrlen = 0; 491 else { 492 *bufp += off; 493 *wrlen = len - off; 494 } 495 return (0); 496 } 497 498 static int 499 kernfs_xwrite(const struct kernfs_node *kfs, char *bf, size_t len) 500 { 501 502 switch (kfs->kfs_type) { 503 case KFShostname: 504 if (bf[len-1] == '\n') 505 --len; 506 memcpy(hostname, bf, len); 507 hostname[len] = '\0'; 508 hostnamelen = (size_t) len; 509 return (0); 510 511 default: 512 return kernfs_try_xwrite(kfs->kfs_type, kfs, bf, len, EIO); 513 } 514 } 515 516 517 /* 518 * vp is the current namei directory 519 * ndp is the name to locate in that directory... 520 */ 521 int 522 kernfs_lookup(void *v) 523 { 524 struct vop_lookup_v2_args /* { 525 struct vnode * a_dvp; 526 struct vnode ** a_vpp; 527 struct componentname * a_cnp; 528 } */ *ap = v; 529 struct componentname *cnp = ap->a_cnp; 530 struct vnode **vpp = ap->a_vpp; 531 struct vnode *dvp = ap->a_dvp; 532 const char *pname = cnp->cn_nameptr; 533 const struct kernfs_node *kfs; 534 const struct kern_target *kt; 535 const struct dyn_kern_target *dkt; 536 const struct kernfs_subdir *ks; 537 int error, i; 538 539 *vpp = NULLVP; 540 541 if (cnp->cn_nameiop == DELETE || cnp->cn_nameiop == RENAME) 542 return (EROFS); 543 544 if (cnp->cn_namelen == 1 && *pname == '.') { 545 *vpp = dvp; 546 vref(dvp); 547 return (0); 548 } 549 550 kfs = VTOKERN(dvp); 551 switch (kfs->kfs_type) { 552 case KFSkern: 553 /* 554 * Shouldn't get here with .. in the root node. 555 */ 556 if (cnp->cn_flags & ISDOTDOT) 557 return (EIO); 558 559 for (i = 0; i < static_nkern_targets; i++) { 560 kt = &kern_targets[i]; 561 if (cnp->cn_namelen == kt->kt_namlen && 562 memcmp(kt->kt_name, pname, cnp->cn_namelen) == 0) 563 goto found; 564 } 565 SIMPLEQ_FOREACH(dkt, &dyn_kern_targets, dkt_queue) { 566 if (cnp->cn_namelen == dkt->dkt_kt.kt_namlen && 567 memcmp(dkt->dkt_kt.kt_name, pname, cnp->cn_namelen) == 0) { 568 kt = &dkt->dkt_kt; 569 goto found; 570 } 571 } 572 break; 573 574 found: 575 error = vcache_get(dvp->v_mount, &kt, sizeof(kt), vpp); 576 return error; 577 578 case KFSsubdir: 579 ks = (struct kernfs_subdir *)kfs->kfs_kt->kt_data; 580 if (cnp->cn_flags & ISDOTDOT) { 581 kt = ks->ks_parent; 582 goto found; 583 } 584 585 SIMPLEQ_FOREACH(dkt, &ks->ks_entries, dkt_queue) { 586 if (cnp->cn_namelen == dkt->dkt_kt.kt_namlen && 587 memcmp(dkt->dkt_kt.kt_name, pname, cnp->cn_namelen) == 0) { 588 kt = &dkt->dkt_kt; 589 goto found; 590 } 591 } 592 break; 593 594 default: 595 return (ENOTDIR); 596 } 597 598 return (cnp->cn_nameiop == LOOKUP ? ENOENT : EROFS); 599 } 600 601 int 602 kernfs_open(void *v) 603 { 604 struct vop_open_args /* { 605 struct vnode *a_vp; 606 int a_mode; 607 kauth_cred_t a_cred; 608 } */ *ap = v; 609 struct kernfs_node *kfs = VTOKERN(ap->a_vp); 610 611 return kernfs_try_fileop(kfs->kfs_type, KERNFS_FILEOP_OPEN, v, 0); 612 } 613 614 int 615 kernfs_close(void *v) 616 { 617 struct vop_close_args /* { 618 struct vnode *a_vp; 619 int a_fflag; 620 kauth_cred_t a_cred; 621 } */ *ap = v; 622 struct kernfs_node *kfs = VTOKERN(ap->a_vp); 623 624 return kernfs_try_fileop(kfs->kfs_type, KERNFS_FILEOP_CLOSE, v, 0); 625 } 626 627 int 628 kernfs_access(void *v) 629 { 630 struct vop_access_args /* { 631 struct vnode *a_vp; 632 int a_mode; 633 kauth_cred_t a_cred; 634 } */ *ap = v; 635 struct vattr va; 636 int error; 637 638 if ((error = VOP_GETATTR(ap->a_vp, &va, ap->a_cred)) != 0) 639 return (error); 640 641 return kauth_authorize_vnode(ap->a_cred, 642 KAUTH_ACCESS_ACTION(ap->a_mode, ap->a_vp->v_type, va.va_mode), 643 ap->a_vp, NULL, genfs_can_access(va.va_type, va.va_mode, 644 va.va_uid, va.va_gid, ap->a_mode, ap->a_cred)); 645 } 646 647 static int 648 kernfs_default_fileop_getattr(void *v) 649 { 650 struct vop_getattr_args /* { 651 struct vnode *a_vp; 652 struct vattr *a_vap; 653 kauth_cred_t a_cred; 654 } */ *ap = v; 655 struct vattr *vap = ap->a_vap; 656 657 vap->va_nlink = 1; 658 vap->va_bytes = vap->va_size = 0; 659 660 return 0; 661 } 662 663 int 664 kernfs_getattr(void *v) 665 { 666 struct vop_getattr_args /* { 667 struct vnode *a_vp; 668 struct vattr *a_vap; 669 kauth_cred_t a_cred; 670 } */ *ap = v; 671 struct kernfs_node *kfs = VTOKERN(ap->a_vp); 672 struct kernfs_subdir *ks; 673 struct vattr *vap = ap->a_vap; 674 int error = 0; 675 char strbuf[KSTRING], *bf; 676 size_t nread, total; 677 678 vattr_null(vap); 679 vap->va_type = ap->a_vp->v_type; 680 vap->va_uid = 0; 681 vap->va_gid = 0; 682 vap->va_mode = kfs->kfs_mode; 683 vap->va_fileid = kfs->kfs_fileno; 684 vap->va_flags = 0; 685 vap->va_size = 0; 686 vap->va_blocksize = DEV_BSIZE; 687 /* Make all times be current TOD, except for the "boottime" node. */ 688 if (kfs->kfs_kt->kt_namlen == 8 && 689 !memcmp(kfs->kfs_kt->kt_name, "boottime", 8)) { 690 vap->va_ctime = boottime; 691 } else { 692 getnanotime(&vap->va_ctime); 693 } 694 vap->va_atime = vap->va_mtime = vap->va_ctime; 695 vap->va_gen = 0; 696 vap->va_flags = 0; 697 vap->va_rdev = 0; 698 vap->va_bytes = 0; 699 700 switch (kfs->kfs_type) { 701 case KFSkern: 702 vap->va_nlink = nkern_dirs; 703 vap->va_bytes = vap->va_size = DEV_BSIZE; 704 break; 705 706 case KFSdevice: 707 vap->va_nlink = 1; 708 vap->va_rdev = ap->a_vp->v_rdev; 709 break; 710 711 case KFSroot: 712 vap->va_nlink = 1; 713 vap->va_bytes = vap->va_size = DEV_BSIZE; 714 break; 715 716 case KFSsubdir: 717 ks = (struct kernfs_subdir *)kfs->kfs_kt->kt_data; 718 vap->va_nlink = ks->ks_dirs; 719 vap->va_bytes = vap->va_size = DEV_BSIZE; 720 break; 721 722 case KFSnull: 723 case KFStime: 724 case KFSint: 725 case KFSstring: 726 case KFShostname: 727 case KFSavenrun: 728 case KFSmsgbuf: 729 vap->va_nlink = 1; 730 total = 0; 731 do { 732 bf = strbuf; 733 error = kernfs_xread(kfs, total, &bf, 734 sizeof(strbuf), &nread); 735 total += nread; 736 } while (error == 0 && nread != 0); 737 vap->va_bytes = vap->va_size = total; 738 break; 739 740 default: 741 error = kernfs_try_fileop(kfs->kfs_type, 742 KERNFS_FILEOP_GETATTR, v, EINVAL); 743 break; 744 } 745 746 return (error); 747 } 748 749 /*ARGSUSED*/ 750 int 751 kernfs_setattr(void *v) 752 { 753 754 /* 755 * Silently ignore attribute changes. 756 * This allows for open with truncate to have no 757 * effect until some data is written. I want to 758 * do it this way because all writes are atomic. 759 */ 760 return (0); 761 } 762 763 int 764 kernfs_default_xread(void *v) 765 { 766 struct vop_read_args /* { 767 struct vnode *a_vp; 768 struct uio *a_uio; 769 int a_ioflag; 770 kauth_cred_t a_cred; 771 } */ *ap = v; 772 struct uio *uio = ap->a_uio; 773 struct kernfs_node *kfs = VTOKERN(ap->a_vp); 774 char strbuf[KSTRING], *bf; 775 int off; 776 size_t len; 777 int error; 778 779 if (ap->a_vp->v_type == VDIR) 780 return EISDIR; 781 782 off = (int)uio->uio_offset; 783 /* Don't allow negative offsets */ 784 if (off < 0) 785 return EINVAL; 786 787 bf = strbuf; 788 if ((error = kernfs_xread(kfs, off, &bf, sizeof(strbuf), &len)) == 0) 789 error = uiomove(bf, len, uio); 790 return (error); 791 } 792 793 int 794 kernfs_read(void *v) 795 { 796 struct vop_read_args /* { 797 struct vnode *a_vp; 798 struct uio *a_uio; 799 int a_ioflag; 800 struct ucred *a_cred; 801 } */ *ap = v; 802 struct kernfs_node *kfs = VTOKERN(ap->a_vp); 803 804 if (kfs->kfs_type < KFSlasttype) { 805 /* use default function */ 806 return kernfs_default_xread(v); 807 } 808 return kernfs_try_fileop(kfs->kfs_type, KERNFS_FILEOP_READ, v, 809 EOPNOTSUPP); 810 } 811 812 static int 813 kernfs_default_xwrite(void *v) 814 { 815 struct vop_write_args /* { 816 struct vnode *a_vp; 817 struct uio *a_uio; 818 int a_ioflag; 819 kauth_cred_t a_cred; 820 } */ *ap = v; 821 struct kernfs_node *kfs = VTOKERN(ap->a_vp); 822 struct uio *uio = ap->a_uio; 823 int error; 824 size_t xlen; 825 char strbuf[KSTRING]; 826 827 if (uio->uio_offset != 0) 828 return (EINVAL); 829 830 xlen = uimin(uio->uio_resid, KSTRING-1); 831 if ((error = uiomove(strbuf, xlen, uio)) != 0) 832 return (error); 833 834 if (uio->uio_resid != 0) 835 return (EIO); 836 837 strbuf[xlen] = '\0'; 838 xlen = strlen(strbuf); 839 return (kernfs_xwrite(kfs, strbuf, xlen)); 840 } 841 842 int 843 kernfs_write(void *v) 844 { 845 struct vop_write_args /* { 846 struct vnode *a_vp; 847 struct uio *a_uio; 848 int a_ioflag; 849 kauth_cred_t a_cred; 850 } */ *ap = v; 851 struct kernfs_node *kfs = VTOKERN(ap->a_vp); 852 853 if (kfs->kfs_type < KFSlasttype) { 854 /* use default function */ 855 return kernfs_default_xwrite(v); 856 } 857 return kernfs_try_fileop(kfs->kfs_type, KERNFS_FILEOP_WRITE, v, 858 EOPNOTSUPP); 859 } 860 861 int 862 kernfs_ioctl(void *v) 863 { 864 struct vop_ioctl_args /* { 865 const struct vnodeop_desc *a_desc; 866 struct vnode *a_vp; 867 u_long a_command; 868 void *a_data; 869 int a_fflag; 870 kauth_cred_t a_cred; 871 } */ *ap = v; 872 struct kernfs_node *kfs = VTOKERN(ap->a_vp); 873 874 return kernfs_try_fileop(kfs->kfs_type, KERNFS_FILEOP_IOCTL, v, 875 EPASSTHROUGH); 876 } 877 878 static int 879 kernfs_setdirentfileno_kt(struct dirent *d, const struct kern_target *kt, 880 struct vop_readdir_args *ap) 881 { 882 struct kernfs_node *kfs; 883 struct vnode *vp; 884 int error; 885 886 if ((error = vcache_get(ap->a_vp->v_mount, &kt, sizeof(kt), &vp)) != 0) 887 return error; 888 kfs = VTOKERN(vp); 889 d->d_fileno = kfs->kfs_fileno; 890 vrele(vp); 891 return 0; 892 } 893 894 static int 895 kernfs_setdirentfileno(struct dirent *d, off_t entry, 896 struct kernfs_node *thisdir_kfs, const struct kern_target *parent_kt, 897 const struct kern_target *kt, struct vop_readdir_args *ap) 898 { 899 const struct kern_target *ikt; 900 int error; 901 902 switch (entry) { 903 case 0: 904 d->d_fileno = thisdir_kfs->kfs_fileno; 905 return 0; 906 case 1: 907 ikt = parent_kt; 908 break; 909 default: 910 ikt = kt; 911 break; 912 } 913 if (ikt != thisdir_kfs->kfs_kt) { 914 if ((error = kernfs_setdirentfileno_kt(d, ikt, ap)) != 0) 915 return error; 916 } else 917 d->d_fileno = thisdir_kfs->kfs_fileno; 918 return 0; 919 } 920 921 int 922 kernfs_readdir(void *v) 923 { 924 struct vop_readdir_args /* { 925 struct vnode *a_vp; 926 struct uio *a_uio; 927 kauth_cred_t a_cred; 928 int *a_eofflag; 929 off_t **a_cookies; 930 int a_*ncookies; 931 } */ *ap = v; 932 struct uio *uio = ap->a_uio; 933 struct dirent d; 934 struct kernfs_node *kfs = VTOKERN(ap->a_vp); 935 const struct kern_target *kt; 936 const struct dyn_kern_target *dkt = NULL; 937 const struct kernfs_subdir *ks; 938 off_t i, j; 939 int error; 940 off_t *cookies = NULL; 941 int ncookies = 0, n; 942 943 if (uio->uio_resid < UIO_MX) 944 return (EINVAL); 945 if (uio->uio_offset < 0) 946 return (EINVAL); 947 948 error = 0; 949 i = uio->uio_offset; 950 memset(&d, 0, sizeof(d)); 951 d.d_reclen = UIO_MX; 952 ncookies = uio->uio_resid / UIO_MX; 953 954 switch (kfs->kfs_type) { 955 case KFSkern: 956 if (i >= nkern_targets) 957 return (0); 958 959 if (ap->a_ncookies) { 960 ncookies = uimin(ncookies, (nkern_targets - i)); 961 cookies = malloc(ncookies * sizeof(off_t), M_TEMP, 962 M_WAITOK); 963 *ap->a_cookies = cookies; 964 } 965 966 n = 0; 967 for (; i < nkern_targets && uio->uio_resid >= UIO_MX; i++) { 968 if (i < static_nkern_targets) 969 kt = &kern_targets[i]; 970 else { 971 if (dkt == NULL) { 972 dkt = SIMPLEQ_FIRST(&dyn_kern_targets); 973 for (j = static_nkern_targets; j < i && 974 dkt != NULL; j++) 975 dkt = SIMPLEQ_NEXT(dkt, dkt_queue); 976 if (j != i) 977 break; 978 } else { 979 dkt = SIMPLEQ_NEXT(dkt, dkt_queue); 980 } 981 if (dkt == NULL) 982 break; 983 kt = &dkt->dkt_kt; 984 } 985 if (kt->kt_tag == KFSmsgbuf) { 986 if (!logenabled(msgbufp)) { 987 continue; 988 } 989 } 990 d.d_namlen = kt->kt_namlen; 991 if ((error = kernfs_setdirentfileno(&d, i, kfs, 992 &kern_targets[0], kt, ap)) != 0) 993 break; 994 memcpy(d.d_name, kt->kt_name, kt->kt_namlen + 1); 995 d.d_type = kt->kt_type; 996 if ((error = uiomove(&d, UIO_MX, uio)) != 0) 997 break; 998 if (cookies) 999 *cookies++ = i + 1; 1000 n++; 1001 } 1002 ncookies = n; 1003 break; 1004 1005 case KFSroot: 1006 if (i >= 2) 1007 return 0; 1008 1009 if (ap->a_ncookies) { 1010 ncookies = uimin(ncookies, (2 - i)); 1011 cookies = malloc(ncookies * sizeof(off_t), M_TEMP, 1012 M_WAITOK); 1013 *ap->a_cookies = cookies; 1014 } 1015 1016 n = 0; 1017 for (; i < 2 && uio->uio_resid >= UIO_MX; i++) { 1018 kt = &kern_targets[i]; 1019 d.d_namlen = kt->kt_namlen; 1020 d.d_fileno = KERNFS_FILENO(kt, kt->kt_tag, 0); 1021 memcpy(d.d_name, kt->kt_name, kt->kt_namlen + 1); 1022 d.d_type = kt->kt_type; 1023 if ((error = uiomove(&d, UIO_MX, uio)) != 0) 1024 break; 1025 if (cookies) 1026 *cookies++ = i + 1; 1027 n++; 1028 } 1029 ncookies = n; 1030 break; 1031 1032 case KFSsubdir: 1033 ks = (struct kernfs_subdir *)kfs->kfs_kt->kt_data; 1034 if (i >= ks->ks_nentries) 1035 return (0); 1036 1037 if (ap->a_ncookies) { 1038 ncookies = uimin(ncookies, (ks->ks_nentries - i)); 1039 cookies = malloc(ncookies * sizeof(off_t), M_TEMP, 1040 M_WAITOK); 1041 *ap->a_cookies = cookies; 1042 } 1043 1044 dkt = SIMPLEQ_FIRST(&ks->ks_entries); 1045 for (j = 0; j < i && dkt != NULL; j++) 1046 dkt = SIMPLEQ_NEXT(dkt, dkt_queue); 1047 n = 0; 1048 for (; i < ks->ks_nentries && uio->uio_resid >= UIO_MX; i++) { 1049 if (i < 2) 1050 kt = &subdir_targets[i]; 1051 else { 1052 /* check if ks_nentries lied to us */ 1053 if (dkt == NULL) 1054 break; 1055 kt = &dkt->dkt_kt; 1056 dkt = SIMPLEQ_NEXT(dkt, dkt_queue); 1057 } 1058 d.d_namlen = kt->kt_namlen; 1059 if ((error = kernfs_setdirentfileno(&d, i, kfs, 1060 ks->ks_parent, kt, ap)) != 0) 1061 break; 1062 memcpy(d.d_name, kt->kt_name, kt->kt_namlen + 1); 1063 d.d_type = kt->kt_type; 1064 if ((error = uiomove(&d, UIO_MX, uio)) != 0) 1065 break; 1066 if (cookies) 1067 *cookies++ = i + 1; 1068 n++; 1069 } 1070 ncookies = n; 1071 break; 1072 1073 default: 1074 error = ENOTDIR; 1075 break; 1076 } 1077 1078 if (ap->a_ncookies) { 1079 if (error) { 1080 if (cookies) 1081 free(*ap->a_cookies, M_TEMP); 1082 *ap->a_ncookies = 0; 1083 *ap->a_cookies = NULL; 1084 } else 1085 *ap->a_ncookies = ncookies; 1086 } 1087 1088 uio->uio_offset = i; 1089 return (error); 1090 } 1091 1092 int 1093 kernfs_inactive(void *v) 1094 { 1095 struct vop_inactive_v2_args /* { 1096 struct vnode *a_vp; 1097 bool *a_recycle; 1098 } */ *ap = v; 1099 1100 *ap->a_recycle = false; 1101 1102 return (0); 1103 } 1104 1105 int 1106 kernfs_reclaim(void *v) 1107 { 1108 struct vop_reclaim_v2_args /* { 1109 struct vnode *a_vp; 1110 } */ *ap = v; 1111 struct vnode *vp = ap->a_vp; 1112 struct kernfs_node *kfs = VTOKERN(vp); 1113 1114 VOP_UNLOCK(vp); 1115 1116 vp->v_data = NULL; 1117 mutex_enter(&kfs_lock); 1118 TAILQ_REMOVE(&VFSTOKERNFS(vp->v_mount)->nodelist, kfs, kfs_list); 1119 mutex_exit(&kfs_lock); 1120 kmem_free(kfs, sizeof(struct kernfs_node)); 1121 1122 return 0; 1123 } 1124 1125 /* 1126 * Return POSIX pathconf information applicable to special devices. 1127 */ 1128 int 1129 kernfs_pathconf(void *v) 1130 { 1131 struct vop_pathconf_args /* { 1132 struct vnode *a_vp; 1133 int a_name; 1134 register_t *a_retval; 1135 } */ *ap = v; 1136 1137 switch (ap->a_name) { 1138 case _PC_LINK_MAX: 1139 *ap->a_retval = LINK_MAX; 1140 return (0); 1141 case _PC_MAX_CANON: 1142 *ap->a_retval = MAX_CANON; 1143 return (0); 1144 case _PC_MAX_INPUT: 1145 *ap->a_retval = MAX_INPUT; 1146 return (0); 1147 case _PC_PIPE_BUF: 1148 *ap->a_retval = PIPE_BUF; 1149 return (0); 1150 case _PC_CHOWN_RESTRICTED: 1151 *ap->a_retval = 1; 1152 return (0); 1153 case _PC_VDISABLE: 1154 *ap->a_retval = _POSIX_VDISABLE; 1155 return (0); 1156 case _PC_SYNC_IO: 1157 *ap->a_retval = 1; 1158 return (0); 1159 default: 1160 return (EINVAL); 1161 } 1162 /* NOTREACHED */ 1163 } 1164 1165 /* 1166 * Print out the contents of a /dev/fd vnode. 1167 */ 1168 /* ARGSUSED */ 1169 int 1170 kernfs_print(void *v) 1171 { 1172 1173 printf("tag VT_KERNFS, kernfs vnode\n"); 1174 return (0); 1175 } 1176 1177 int 1178 kernfs_link(void *v) 1179 { 1180 struct vop_link_v2_args /* { 1181 struct vnode *a_dvp; 1182 struct vnode *a_vp; 1183 struct componentname *a_cnp; 1184 } */ *ap = v; 1185 1186 VOP_ABORTOP(ap->a_dvp, ap->a_cnp); 1187 return (EROFS); 1188 } 1189 1190 int 1191 kernfs_symlink(void *v) 1192 { 1193 struct vop_symlink_v3_args /* { 1194 struct vnode *a_dvp; 1195 struct vnode **a_vpp; 1196 struct componentname *a_cnp; 1197 struct vattr *a_vap; 1198 char *a_target; 1199 } */ *ap = v; 1200 1201 VOP_ABORTOP(ap->a_dvp, ap->a_cnp); 1202 return (EROFS); 1203 } 1204 1205 int 1206 kernfs_getpages(void *v) 1207 { 1208 struct vop_getpages_args /* { 1209 struct vnode *a_vp; 1210 voff_t a_offset; 1211 struct vm_page **a_m; 1212 int *a_count; 1213 int a_centeridx; 1214 vm_prot_t a_access_type; 1215 int a_advice; 1216 int a_flags; 1217 } */ *ap = v; 1218 1219 if ((ap->a_flags & PGO_LOCKED) == 0) 1220 mutex_exit(ap->a_vp->v_interlock); 1221 1222 return (EFAULT); 1223 } 1224
Indexes created Wed Oct 01 19:09:53 GMT 2025