kernfs_vnops.c revision 1.72
1 /* $NetBSD: kernfs_vnops.c,v 1.72 2001/01/27 11:42:41 jdolecek 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. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the University of 21 * California, Berkeley and its contributors. 22 * 4. Neither the name of the University nor the names of its contributors 23 * may be used to endorse or promote products derived from this software 24 * without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 * 38 * @(#)kernfs_vnops.c 8.15 (Berkeley) 5/21/95 39 */ 40 41 /* 42 * Kernel parameter filesystem (/kern) 43 */ 44 45 #include <sys/param.h> 46 #include <sys/systm.h> 47 #include <sys/kernel.h> 48 #include <sys/vmmeter.h> 49 #include <sys/types.h> 50 #include <sys/time.h> 51 #include <sys/proc.h> 52 #include <sys/vnode.h> 53 #include <sys/malloc.h> 54 #include <sys/file.h> 55 #include <sys/stat.h> 56 #include <sys/mount.h> 57 #include <sys/namei.h> 58 #include <sys/buf.h> 59 #include <sys/dirent.h> 60 #include <sys/msgbuf.h> 61 62 #include <miscfs/genfs/genfs.h> 63 #include <miscfs/kernfs/kernfs.h> 64 65 #include <uvm/uvm_extern.h> 66 67 #define KSTRING 256 /* Largest I/O available via this filesystem */ 68 #define UIO_MX 32 69 70 #define READ_MODE (S_IRUSR|S_IRGRP|S_IROTH) 71 #define WRITE_MODE (S_IWUSR|S_IRUSR|S_IRGRP|S_IROTH) 72 #define DIR_MODE (S_IRUSR|S_IXUSR|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH) 73 74 struct kern_target kern_targets[] = { 75 /* NOTE: The name must be less than UIO_MX-16 chars in length */ 76 #define N(s) sizeof(s)-1, s 77 /* name data tag type ro/rw */ 78 { DT_DIR, N("."), 0, KTT_NULL, VDIR, DIR_MODE }, 79 { DT_DIR, N(".."), 0, KTT_NULL, VDIR, DIR_MODE }, 80 { DT_REG, N("boottime"), &boottime.tv_sec, KTT_INT, VREG, READ_MODE }, 81 /* XXX cast away const */ 82 { DT_REG, N("copyright"), (void *)copyright, 83 KTT_STRING, VREG, READ_MODE }, 84 { DT_REG, N("hostname"), 0, KTT_HOSTNAME, VREG, WRITE_MODE }, 85 { DT_REG, N("hz"), &hz, KTT_INT, VREG, READ_MODE }, 86 { DT_REG, N("loadavg"), 0, KTT_AVENRUN, VREG, READ_MODE }, 87 { DT_REG, N("msgbuf"), 0, KTT_MSGBUF, VREG, READ_MODE }, 88 { DT_REG, N("pagesize"), &uvmexp.pagesize, KTT_INT, VREG, READ_MODE }, 89 { DT_REG, N("physmem"), 0, KTT_PHYSMEM, VREG, READ_MODE }, 90 #if 0 91 { DT_DIR, N("root"), 0, KTT_NULL, VDIR, DIR_MODE }, 92 #endif 93 { DT_BLK, N("rootdev"), &rootdev, KTT_DEVICE, VBLK, READ_MODE }, 94 { DT_CHR, N("rrootdev"), &rrootdev, KTT_DEVICE, VCHR, READ_MODE }, 95 { DT_REG, N("time"), 0, KTT_TIME, VREG, READ_MODE }, 96 /* XXX cast away const */ 97 { DT_REG, N("version"), (void *)version, 98 KTT_STRING, VREG, READ_MODE }, 99 #undef N 100 }; 101 static int nkern_targets = sizeof(kern_targets) / sizeof(kern_targets[0]); 102 103 int kernfs_lookup __P((void *)); 104 #define kernfs_create genfs_eopnotsupp_rele 105 #define kernfs_mknod genfs_eopnotsupp_rele 106 #define kernfs_open genfs_nullop 107 #define kernfs_close genfs_nullop 108 int kernfs_access __P((void *)); 109 int kernfs_getattr __P((void *)); 110 int kernfs_setattr __P((void *)); 111 int kernfs_read __P((void *)); 112 int kernfs_write __P((void *)); 113 #define kernfs_fcntl genfs_fcntl 114 #define kernfs_ioctl genfs_enoioctl 115 #define kernfs_poll genfs_poll 116 #define kernfs_revoke genfs_revoke 117 #define kernfs_mmap genfs_eopnotsupp 118 #define kernfs_fsync genfs_nullop 119 #define kernfs_seek genfs_nullop 120 #define kernfs_remove genfs_eopnotsupp_rele 121 int kernfs_link __P((void *)); 122 #define kernfs_rename genfs_eopnotsupp_rele 123 #define kernfs_mkdir genfs_eopnotsupp_rele 124 #define kernfs_rmdir genfs_eopnotsupp_rele 125 int kernfs_symlink __P((void *)); 126 int kernfs_readdir __P((void *)); 127 #define kernfs_readlink genfs_eopnotsupp 128 #define kernfs_abortop genfs_abortop 129 int kernfs_inactive __P((void *)); 130 int kernfs_reclaim __P((void *)); 131 #define kernfs_lock genfs_lock 132 #define kernfs_unlock genfs_unlock 133 #define kernfs_bmap genfs_badop 134 #define kernfs_strategy genfs_badop 135 int kernfs_print __P((void *)); 136 #define kernfs_islocked genfs_islocked 137 int kernfs_pathconf __P((void *)); 138 #define kernfs_advlock genfs_einval 139 #define kernfs_blkatoff genfs_eopnotsupp 140 #define kernfs_valloc genfs_eopnotsupp 141 #define kernfs_vfree genfs_nullop 142 #define kernfs_truncate genfs_eopnotsupp 143 #define kernfs_update genfs_nullop 144 #define kernfs_bwrite genfs_eopnotsupp 145 146 int kernfs_xread __P((struct kern_target *, int, char **, int)); 147 int kernfs_xwrite __P((struct kern_target *, char *, int)); 148 149 int (**kernfs_vnodeop_p) __P((void *)); 150 const struct vnodeopv_entry_desc kernfs_vnodeop_entries[] = { 151 { &vop_default_desc, vn_default_error }, 152 { &vop_lookup_desc, kernfs_lookup }, /* lookup */ 153 { &vop_create_desc, kernfs_create }, /* create */ 154 { &vop_mknod_desc, kernfs_mknod }, /* mknod */ 155 { &vop_open_desc, kernfs_open }, /* open */ 156 { &vop_close_desc, kernfs_close }, /* close */ 157 { &vop_access_desc, kernfs_access }, /* access */ 158 { &vop_getattr_desc, kernfs_getattr }, /* getattr */ 159 { &vop_setattr_desc, kernfs_setattr }, /* setattr */ 160 { &vop_read_desc, kernfs_read }, /* read */ 161 { &vop_write_desc, kernfs_write }, /* write */ 162 { &vop_fcntl_desc, kernfs_fcntl }, /* fcntl */ 163 { &vop_ioctl_desc, kernfs_ioctl }, /* ioctl */ 164 { &vop_poll_desc, kernfs_poll }, /* poll */ 165 { &vop_revoke_desc, kernfs_revoke }, /* revoke */ 166 { &vop_mmap_desc, kernfs_mmap }, /* mmap */ 167 { &vop_fsync_desc, kernfs_fsync }, /* fsync */ 168 { &vop_seek_desc, kernfs_seek }, /* seek */ 169 { &vop_remove_desc, kernfs_remove }, /* remove */ 170 { &vop_link_desc, kernfs_link }, /* link */ 171 { &vop_rename_desc, kernfs_rename }, /* rename */ 172 { &vop_mkdir_desc, kernfs_mkdir }, /* mkdir */ 173 { &vop_rmdir_desc, kernfs_rmdir }, /* rmdir */ 174 { &vop_symlink_desc, kernfs_symlink }, /* symlink */ 175 { &vop_readdir_desc, kernfs_readdir }, /* readdir */ 176 { &vop_readlink_desc, kernfs_readlink }, /* readlink */ 177 { &vop_abortop_desc, kernfs_abortop }, /* abortop */ 178 { &vop_inactive_desc, kernfs_inactive }, /* inactive */ 179 { &vop_reclaim_desc, kernfs_reclaim }, /* reclaim */ 180 { &vop_lock_desc, kernfs_lock }, /* lock */ 181 { &vop_unlock_desc, kernfs_unlock }, /* unlock */ 182 { &vop_bmap_desc, kernfs_bmap }, /* bmap */ 183 { &vop_strategy_desc, kernfs_strategy }, /* strategy */ 184 { &vop_print_desc, kernfs_print }, /* print */ 185 { &vop_islocked_desc, kernfs_islocked }, /* islocked */ 186 { &vop_pathconf_desc, kernfs_pathconf }, /* pathconf */ 187 { &vop_advlock_desc, kernfs_advlock }, /* advlock */ 188 { &vop_blkatoff_desc, kernfs_blkatoff }, /* blkatoff */ 189 { &vop_valloc_desc, kernfs_valloc }, /* valloc */ 190 { &vop_vfree_desc, kernfs_vfree }, /* vfree */ 191 { &vop_truncate_desc, kernfs_truncate }, /* truncate */ 192 { &vop_update_desc, kernfs_update }, /* update */ 193 { &vop_bwrite_desc, kernfs_bwrite }, /* bwrite */ 194 { (struct vnodeop_desc*)NULL, (int(*) __P((void *)))NULL } 195 }; 196 const struct vnodeopv_desc kernfs_vnodeop_opv_desc = 197 { &kernfs_vnodeop_p, kernfs_vnodeop_entries }; 198 199 int 200 kernfs_xread(kt, off, bufp, len) 201 struct kern_target *kt; 202 int off; 203 char **bufp; 204 int len; 205 { 206 207 switch (kt->kt_tag) { 208 case KTT_TIME: { 209 struct timeval tv; 210 211 microtime(&tv); 212 sprintf(*bufp, "%ld %ld\n", tv.tv_sec, tv.tv_usec); 213 break; 214 } 215 216 case KTT_INT: { 217 int *ip = kt->kt_data; 218 219 sprintf(*bufp, "%d\n", *ip); 220 break; 221 } 222 223 case KTT_STRING: { 224 char *cp = kt->kt_data; 225 226 *bufp = cp; 227 break; 228 } 229 230 case KTT_MSGBUF: { 231 long n; 232 233 /* 234 * deal with cases where the message buffer has 235 * become corrupted. 236 */ 237 if (!msgbufenabled || msgbufp->msg_magic != MSG_MAGIC) { 238 msgbufenabled = 0; 239 return (ENXIO); 240 } 241 242 /* 243 * Note that reads of /kern/msgbuf won't necessarily yield 244 * consistent results, if the message buffer is modified 245 * while the read is in progress. The worst that can happen 246 * is that incorrect data will be read. There's no way 247 * that this can crash the system unless the values in the 248 * message buffer header are corrupted, but that'll cause 249 * the system to die anyway. 250 */ 251 if (off >= msgbufp->msg_bufs) 252 return (0); 253 n = msgbufp->msg_bufx + off; 254 if (n >= msgbufp->msg_bufs) 255 n -= msgbufp->msg_bufs; 256 len = min(msgbufp->msg_bufs - n, msgbufp->msg_bufs - off); 257 *bufp = msgbufp->msg_bufc + n; 258 return (len); 259 } 260 261 case KTT_HOSTNAME: { 262 char *cp = hostname; 263 int xlen = hostnamelen; 264 265 if (xlen >= (len-2)) 266 return (EINVAL); 267 268 memcpy(*bufp, cp, xlen); 269 (*bufp)[xlen] = '\n'; 270 (*bufp)[xlen+1] = '\0'; 271 break; 272 } 273 274 case KTT_AVENRUN: 275 averunnable.fscale = FSCALE; 276 sprintf(*bufp, "%d %d %d %ld\n", 277 averunnable.ldavg[0], averunnable.ldavg[1], 278 averunnable.ldavg[2], averunnable.fscale); 279 break; 280 281 case KTT_PHYSMEM: 282 sprintf(*bufp, "%llu", (u_int64_t) ctob(physmem)); 283 break; 284 285 default: 286 return (0); 287 } 288 289 len = strlen(*bufp); 290 if (len <= off) 291 return (0); 292 *bufp += off; 293 return (len - off); 294 } 295 296 int 297 kernfs_xwrite(kt, buf, len) 298 struct kern_target *kt; 299 char *buf; 300 int len; 301 { 302 303 switch (kt->kt_tag) { 304 case KTT_HOSTNAME: 305 if (buf[len-1] == '\n') 306 --len; 307 memcpy(hostname, buf, len); 308 hostname[len] = '\0'; 309 hostnamelen = len; 310 return (0); 311 312 default: 313 return (EIO); 314 } 315 } 316 317 318 /* 319 * vp is the current namei directory 320 * ndp is the name to locate in that directory... 321 */ 322 int 323 kernfs_lookup(v) 324 void *v; 325 { 326 struct vop_lookup_args /* { 327 struct vnode * a_dvp; 328 struct vnode ** a_vpp; 329 struct componentname * a_cnp; 330 } */ *ap = v; 331 struct componentname *cnp = ap->a_cnp; 332 struct vnode **vpp = ap->a_vpp; 333 struct vnode *dvp = ap->a_dvp; 334 const char *pname = cnp->cn_nameptr; 335 struct kern_target *kt; 336 struct vnode *fvp; 337 int error, i, wantpunlock; 338 339 #ifdef KERNFS_DIAGNOSTIC 340 printf("kernfs_lookup(%p)\n", ap); 341 printf("kernfs_lookup(dp = %p, vpp = %p, cnp = %p)\n", dvp, vpp, ap->a_cnp); 342 printf("kernfs_lookup(%s)\n", pname); 343 #endif 344 345 *vpp = NULLVP; 346 cnp->cn_flags &= ~PDIRUNLOCK; 347 348 if (cnp->cn_nameiop == DELETE || cnp->cn_nameiop == RENAME) 349 return (EROFS); 350 351 if (cnp->cn_namelen == 1 && *pname == '.') { 352 *vpp = dvp; 353 VREF(dvp); 354 return (0); 355 } 356 357 /* 358 * This code only supports a flat directory, so we don't 359 * need to worry about .. 360 */ 361 362 #if 0 363 if (cnp->cn_namelen == 4 && memcmp(pname, "root", 4) == 0) { 364 *vpp = rootdir; 365 VREF(rootdir); 366 vn_lock(rootdir, LK_SHARED | LK_RETRY); 367 return (0); 368 } 369 #endif 370 371 wantpunlock = (~cnp->cn_flags & (LOCKPARENT | ISLASTCN)); 372 373 for (kt = kern_targets, i = 0; i < nkern_targets; kt++, i++) { 374 if (cnp->cn_namelen == kt->kt_namlen && 375 memcmp(kt->kt_name, pname, cnp->cn_namelen) == 0) 376 goto found; 377 } 378 379 #ifdef KERNFS_DIAGNOSTIC 380 printf("kernfs_lookup: i = %d, failed", i); 381 #endif 382 383 return (cnp->cn_nameiop == LOOKUP ? ENOENT : EROFS); 384 385 found: 386 if (kt->kt_tag == KTT_DEVICE) { 387 dev_t *dp = kt->kt_data; 388 loop: 389 if (*dp == NODEV || !vfinddev(*dp, kt->kt_vtype, &fvp)) { 390 return (ENOENT); 391 } 392 *vpp = fvp; 393 if (vget(fvp, LK_EXCLUSIVE)) 394 goto loop; 395 if (wantpunlock) { 396 VOP_UNLOCK(dvp, 0); 397 cnp->cn_flags |= PDIRUNLOCK; 398 } 399 return (0); 400 } 401 402 #ifdef KERNFS_DIAGNOSTIC 403 printf("kernfs_lookup: allocate new vnode\n"); 404 #endif 405 error = getnewvnode(VT_KERNFS, dvp->v_mount, kernfs_vnodeop_p, &fvp); 406 if (error) { 407 return (error); 408 } 409 410 MALLOC(fvp->v_data, void *, sizeof(struct kernfs_node), M_TEMP, 411 M_WAITOK); 412 VTOKERN(fvp)->kf_kt = kt; 413 fvp->v_type = kt->kt_vtype; 414 vn_lock(fvp, LK_EXCLUSIVE | LK_RETRY); 415 *vpp = fvp; 416 417 #ifdef KERNFS_DIAGNOSTIC 418 printf("kernfs_lookup: newvp = %p\n", fvp); 419 #endif 420 if (wantpunlock) { 421 VOP_UNLOCK(dvp, 0); 422 cnp->cn_flags |= PDIRUNLOCK; 423 } 424 return (0); 425 } 426 427 int 428 kernfs_access(v) 429 void *v; 430 { 431 struct vop_access_args /* { 432 struct vnode *a_vp; 433 int a_mode; 434 struct ucred *a_cred; 435 struct proc *a_p; 436 } */ *ap = v; 437 struct vnode *vp = ap->a_vp; 438 mode_t mode; 439 440 if (vp->v_flag & VROOT) { 441 mode = DIR_MODE; 442 } else { 443 struct kern_target *kt = VTOKERN(vp)->kf_kt; 444 mode = kt->kt_mode; 445 } 446 447 return (vaccess(vp->v_type, mode, (uid_t)0, (gid_t)0, ap->a_mode, 448 ap->a_cred)); 449 } 450 451 int 452 kernfs_getattr(v) 453 void *v; 454 { 455 struct vop_getattr_args /* { 456 struct vnode *a_vp; 457 struct vattr *a_vap; 458 struct ucred *a_cred; 459 struct proc *a_p; 460 } */ *ap = v; 461 struct vnode *vp = ap->a_vp; 462 struct vattr *vap = ap->a_vap; 463 struct timeval tv; 464 int error = 0; 465 char strbuf[KSTRING], *buf; 466 467 memset((caddr_t) vap, 0, sizeof(*vap)); 468 vattr_null(vap); 469 vap->va_uid = 0; 470 vap->va_gid = 0; 471 vap->va_fsid = vp->v_mount->mnt_stat.f_fsid.val[0]; 472 vap->va_size = 0; 473 vap->va_blocksize = DEV_BSIZE; 474 microtime(&tv); 475 TIMEVAL_TO_TIMESPEC(&tv, &vap->va_atime); 476 vap->va_mtime = vap->va_atime; 477 vap->va_ctime = vap->va_ctime; 478 vap->va_gen = 0; 479 vap->va_flags = 0; 480 vap->va_rdev = 0; 481 vap->va_bytes = 0; 482 483 if (vp->v_flag & VROOT) { 484 #ifdef KERNFS_DIAGNOSTIC 485 printf("kernfs_getattr: stat rootdir\n"); 486 #endif 487 vap->va_type = VDIR; 488 vap->va_mode = DIR_MODE; 489 vap->va_nlink = 2; 490 vap->va_fileid = 2; 491 vap->va_size = DEV_BSIZE; 492 } else { 493 struct kern_target *kt = VTOKERN(vp)->kf_kt; 494 int nbytes, total; 495 #ifdef KERNFS_DIAGNOSTIC 496 printf("kernfs_getattr: stat target %s\n", kt->kt_name); 497 #endif 498 vap->va_type = kt->kt_vtype; 499 vap->va_mode = kt->kt_mode; 500 vap->va_nlink = 1; 501 vap->va_fileid = 1 + (kt - kern_targets); 502 total = 0; 503 while (buf = strbuf, 504 nbytes = kernfs_xread(kt, total, &buf, sizeof(strbuf))) 505 total += nbytes; 506 vap->va_size = total; 507 } 508 509 #ifdef KERNFS_DIAGNOSTIC 510 printf("kernfs_getattr: return error %d\n", error); 511 #endif 512 return (error); 513 } 514 515 /*ARGSUSED*/ 516 int 517 kernfs_setattr(v) 518 void *v; 519 { 520 /* 521 * Silently ignore attribute changes. 522 * This allows for open with truncate to have no 523 * effect until some data is written. I want to 524 * do it this way because all writes are atomic. 525 */ 526 return (0); 527 } 528 529 int 530 kernfs_read(v) 531 void *v; 532 { 533 struct vop_read_args /* { 534 struct vnode *a_vp; 535 struct uio *a_uio; 536 int a_ioflag; 537 struct ucred *a_cred; 538 } */ *ap = v; 539 struct vnode *vp = ap->a_vp; 540 struct uio *uio = ap->a_uio; 541 struct kern_target *kt; 542 char strbuf[KSTRING], *buf; 543 int off, len; 544 int error; 545 546 if (vp->v_type == VDIR) 547 return (EOPNOTSUPP); 548 549 kt = VTOKERN(vp)->kf_kt; 550 551 #ifdef KERNFS_DIAGNOSTIC 552 printf("kern_read %s\n", kt->kt_name); 553 #endif 554 555 off = uio->uio_offset; 556 #if 0 557 while (buf = strbuf, 558 #else 559 if (buf = strbuf, 560 #endif 561 len = kernfs_xread(kt, off, &buf, sizeof(strbuf))) { 562 if ((error = uiomove(buf, len, uio)) != 0) 563 return (error); 564 off += len; 565 } 566 return (0); 567 } 568 569 int 570 kernfs_write(v) 571 void *v; 572 { 573 struct vop_write_args /* { 574 struct vnode *a_vp; 575 struct uio *a_uio; 576 int a_ioflag; 577 struct ucred *a_cred; 578 } */ *ap = v; 579 struct vnode *vp = ap->a_vp; 580 struct uio *uio = ap->a_uio; 581 struct kern_target *kt; 582 int error, xlen; 583 char strbuf[KSTRING]; 584 585 if (vp->v_type == VDIR) 586 return (EOPNOTSUPP); 587 588 kt = VTOKERN(vp)->kf_kt; 589 590 if (uio->uio_offset != 0) 591 return (EINVAL); 592 593 xlen = min(uio->uio_resid, KSTRING-1); 594 if ((error = uiomove(strbuf, xlen, uio)) != 0) 595 return (error); 596 597 if (uio->uio_resid != 0) 598 return (EIO); 599 600 strbuf[xlen] = '\0'; 601 xlen = strlen(strbuf); 602 return (kernfs_xwrite(kt, strbuf, xlen)); 603 } 604 605 int 606 kernfs_readdir(v) 607 void *v; 608 { 609 struct vop_readdir_args /* { 610 struct vnode *a_vp; 611 struct uio *a_uio; 612 struct ucred *a_cred; 613 int *a_eofflag; 614 off_t **a_cookies; 615 int a_*ncookies; 616 } */ *ap = v; 617 struct uio *uio = ap->a_uio; 618 struct dirent d; 619 struct kern_target *kt; 620 off_t i; 621 int error; 622 off_t *cookies = NULL; 623 int ncookies = 0, nc = 0; 624 625 if (ap->a_vp->v_type != VDIR) 626 return (ENOTDIR); 627 628 if (uio->uio_resid < UIO_MX) 629 return (EINVAL); 630 if (uio->uio_offset < 0) 631 return (EINVAL); 632 633 error = 0; 634 i = uio->uio_offset; 635 636 if (i >= nkern_targets) 637 return 0; 638 639 memset((caddr_t)&d, 0, UIO_MX); 640 d.d_reclen = UIO_MX; 641 642 if (ap->a_ncookies) { 643 nc = uio->uio_resid / UIO_MX; 644 nc = min(nc, (nkern_targets - i)); 645 cookies = malloc(nc * sizeof(off_t), M_TEMP, M_WAITOK); 646 *ap->a_cookies = cookies; 647 } 648 649 for (kt = &kern_targets[i]; 650 uio->uio_resid >= UIO_MX && i < nkern_targets; kt++, i++) { 651 #ifdef KERNFS_DIAGNOSTIC 652 printf("kernfs_readdir: i = %d\n", i); 653 #endif 654 655 if (kt->kt_tag == KTT_DEVICE) { 656 dev_t *dp = kt->kt_data; 657 struct vnode *fvp; 658 659 if (*dp == NODEV || !vfinddev(*dp, kt->kt_vtype, &fvp)) 660 continue; 661 } 662 663 d.d_fileno = i + 3; 664 d.d_namlen = kt->kt_namlen; 665 memcpy(d.d_name, kt->kt_name, kt->kt_namlen + 1); 666 d.d_type = kt->kt_type; 667 668 if ((error = uiomove((caddr_t)&d, UIO_MX, uio)) != 0) 669 break; 670 if (cookies) { 671 *cookies++ = i + 1; 672 ncookies++; 673 } 674 } 675 676 if (ap->a_ncookies) { 677 if (error) { 678 free(*ap->a_cookies, M_TEMP); 679 *ap->a_ncookies = 0; 680 *ap->a_cookies = NULL; 681 } else 682 *ap->a_ncookies = ncookies; 683 } 684 685 uio->uio_offset = i; 686 return (error); 687 } 688 689 int 690 kernfs_inactive(v) 691 void *v; 692 { 693 struct vop_inactive_args /* { 694 struct vnode *a_vp; 695 struct proc *a_p; 696 } */ *ap = v; 697 struct vnode *vp = ap->a_vp; 698 699 #ifdef KERNFS_DIAGNOSTIC 700 printf("kernfs_inactive(%p)\n", vp); 701 #endif 702 /* 703 * Clear out the v_type field to avoid 704 * nasty things happening in vgone(). 705 */ 706 VOP_UNLOCK(vp, 0); 707 vp->v_type = VNON; 708 return (0); 709 } 710 711 int 712 kernfs_reclaim(v) 713 void *v; 714 { 715 struct vop_reclaim_args /* { 716 struct vnode *a_vp; 717 } */ *ap = v; 718 struct vnode *vp = ap->a_vp; 719 720 #ifdef KERNFS_DIAGNOSTIC 721 printf("kernfs_reclaim(%p)\n", vp); 722 #endif 723 if (vp->v_data) { 724 FREE(vp->v_data, M_TEMP); 725 vp->v_data = 0; 726 } 727 return (0); 728 } 729 730 /* 731 * Return POSIX pathconf information applicable to special devices. 732 */ 733 int 734 kernfs_pathconf(v) 735 void *v; 736 { 737 struct vop_pathconf_args /* { 738 struct vnode *a_vp; 739 int a_name; 740 register_t *a_retval; 741 } */ *ap = v; 742 743 switch (ap->a_name) { 744 case _PC_LINK_MAX: 745 *ap->a_retval = LINK_MAX; 746 return (0); 747 case _PC_MAX_CANON: 748 *ap->a_retval = MAX_CANON; 749 return (0); 750 case _PC_MAX_INPUT: 751 *ap->a_retval = MAX_INPUT; 752 return (0); 753 case _PC_PIPE_BUF: 754 *ap->a_retval = PIPE_BUF; 755 return (0); 756 case _PC_CHOWN_RESTRICTED: 757 *ap->a_retval = 1; 758 return (0); 759 case _PC_VDISABLE: 760 *ap->a_retval = _POSIX_VDISABLE; 761 return (0); 762 case _PC_SYNC_IO: 763 *ap->a_retval = 1; 764 return (0); 765 default: 766 return (EINVAL); 767 } 768 /* NOTREACHED */ 769 } 770 771 /* 772 * Print out the contents of a /dev/fd vnode. 773 */ 774 /* ARGSUSED */ 775 int 776 kernfs_print(v) 777 void *v; 778 { 779 780 printf("tag VT_KERNFS, kernfs vnode\n"); 781 return (0); 782 } 783 784 int 785 kernfs_link(v) 786 void *v; 787 { 788 struct vop_link_args /* { 789 struct vnode *a_dvp; 790 struct vnode *a_vp; 791 struct componentname *a_cnp; 792 } */ *ap = v; 793 794 VOP_ABORTOP(ap->a_dvp, ap->a_cnp); 795 vput(ap->a_dvp); 796 return (EROFS); 797 } 798 799 int 800 kernfs_symlink(v) 801 void *v; 802 { 803 struct vop_symlink_args /* { 804 struct vnode *a_dvp; 805 struct vnode **a_vpp; 806 struct componentname *a_cnp; 807 struct vattr *a_vap; 808 char *a_target; 809 } */ *ap = v; 810 811 VOP_ABORTOP(ap->a_dvp, ap->a_cnp); 812 vput(ap->a_dvp); 813 return (EROFS); 814 } 815
Indexes created Wed Oct 01 19:09:53 GMT 2025