1 /* $NetBSD: procfs_vnops.c,v 1.52 1997/10/10 02:01:05 fvdl Exp $ */ 2 3 /* 4 * Copyright (c) 1993 Jan-Simon Pendry 5 * Copyright (c) 1993 6 * The Regents of the University of California. All rights reserved. 7 * 8 * This code is derived from software contributed to Berkeley by 9 * Jan-Simon Pendry. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. All advertising materials mentioning features or use of this software 20 * must display the following acknowledgement: 21 * This product includes software developed by the University of 22 * California, Berkeley and its contributors. 23 * 4. Neither the name of the University nor the names of its contributors 24 * may be used to endorse or promote products derived from this software 25 * without specific prior written permission. 26 * 27 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 28 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 29 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 30 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 31 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 32 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 33 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 34 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 35 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 36 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 37 * SUCH DAMAGE. 38 * 39 * @(#)procfs_vnops.c 8.8 (Berkeley) 6/15/94 40 */ 41 42 /* 43 * procfs vnode interface 44 */ 45 46 #include <sys/param.h> 47 #include <sys/systm.h> 48 #include <sys/time.h> 49 #include <sys/kernel.h> 50 #include <sys/file.h> 51 #include <sys/proc.h> 52 #include <sys/vnode.h> 53 #include <sys/namei.h> 54 #include <sys/malloc.h> 55 #include <sys/dirent.h> 56 #include <sys/resourcevar.h> 57 #include <sys/ptrace.h> 58 #include <sys/stat.h> 59 60 #include <vm/vm.h> /* for PAGE_SIZE */ 61 62 #include <machine/reg.h> 63 64 #include <miscfs/genfs/genfs.h> 65 #include <miscfs/procfs/procfs.h> 66 67 /* 68 * Vnode Operations. 69 * 70 */ 71 72 /* 73 * This is a list of the valid names in the 74 * process-specific sub-directories. It is 75 * used in procfs_lookup and procfs_readdir 76 */ 77 struct proc_target { 78 u_char pt_type; 79 u_char pt_namlen; 80 char *pt_name; 81 pfstype pt_pfstype; 82 int (*pt_valid) __P((struct proc *p)); 83 } proc_targets[] = { 84 #define N(s) sizeof(s)-1, s 85 /* name type validp */ 86 { DT_DIR, N("."), Pproc, NULL }, 87 { DT_DIR, N(".."), Proot, NULL }, 88 { DT_REG, N("file"), Pfile, procfs_validfile }, 89 { DT_REG, N("mem"), Pmem, NULL }, 90 { DT_REG, N("regs"), Pregs, procfs_validregs }, 91 { DT_REG, N("fpregs"), Pfpregs, procfs_validfpregs }, 92 { DT_REG, N("ctl"), Pctl, NULL }, 93 { DT_REG, N("status"), Pstatus, NULL }, 94 { DT_REG, N("note"), Pnote, NULL }, 95 { DT_REG, N("notepg"), Pnotepg, NULL }, 96 #undef N 97 }; 98 static int nproc_targets = sizeof(proc_targets) / sizeof(proc_targets[0]); 99 100 static pid_t atopid __P((const char *, u_int)); 101 102 int procfs_lookup __P((void *)); 103 #define procfs_create genfs_eopnotsupp 104 #define procfs_mknod genfs_eopnotsupp 105 int procfs_open __P((void *)); 106 int procfs_close __P((void *)); 107 int procfs_access __P((void *)); 108 int procfs_getattr __P((void *)); 109 int procfs_setattr __P((void *)); 110 #define procfs_read procfs_rw 111 #define procfs_write procfs_rw 112 #define procfs_ioctl genfs_eopnotsupp 113 #define procfs_poll genfs_poll 114 #define procfs_mmap genfs_eopnotsupp 115 #define procfs_fsync genfs_nullop 116 #define procfs_seek genfs_nullop 117 #define procfs_remove genfs_eopnotsupp 118 int procfs_link __P((void *)); 119 #define procfs_rename genfs_eopnotsupp 120 #define procfs_mkdir genfs_eopnotsupp 121 #define procfs_rmdir genfs_eopnotsupp 122 int procfs_symlink __P((void *)); 123 int procfs_readdir __P((void *)); 124 int procfs_readlink __P((void *)); 125 #define procfs_abortop genfs_abortop 126 int procfs_inactive __P((void *)); 127 int procfs_reclaim __P((void *)); 128 #define procfs_lock genfs_nullop 129 #define procfs_unlock genfs_nullop 130 int procfs_bmap __P((void *)); 131 #define procfs_strategy genfs_badop 132 int procfs_print __P((void *)); 133 int procfs_pathconf __P((void *)); 134 #define procfs_islocked genfs_nullop 135 #define procfs_advlock genfs_eopnotsupp 136 #define procfs_blkatoff genfs_eopnotsupp 137 #define procfs_valloc genfs_eopnotsupp 138 #define procfs_vfree genfs_nullop 139 #define procfs_truncate genfs_eopnotsupp 140 #define procfs_update genfs_nullop 141 #define procfs_bwrite genfs_eopnotsupp 142 143 static pid_t atopid __P((const char *, u_int)); 144 145 /* 146 * procfs vnode operations. 147 */ 148 int (**procfs_vnodeop_p) __P((void *)); 149 struct vnodeopv_entry_desc procfs_vnodeop_entries[] = { 150 { &vop_default_desc, vn_default_error }, 151 { &vop_lookup_desc, procfs_lookup }, /* lookup */ 152 { &vop_create_desc, procfs_create }, /* create */ 153 { &vop_mknod_desc, procfs_mknod }, /* mknod */ 154 { &vop_open_desc, procfs_open }, /* open */ 155 { &vop_close_desc, procfs_close }, /* close */ 156 { &vop_access_desc, procfs_access }, /* access */ 157 { &vop_getattr_desc, procfs_getattr }, /* getattr */ 158 { &vop_setattr_desc, procfs_setattr }, /* setattr */ 159 { &vop_read_desc, procfs_read }, /* read */ 160 { &vop_write_desc, procfs_write }, /* write */ 161 { &vop_ioctl_desc, procfs_ioctl }, /* ioctl */ 162 { &vop_poll_desc, procfs_poll }, /* poll */ 163 { &vop_mmap_desc, procfs_mmap }, /* mmap */ 164 { &vop_fsync_desc, procfs_fsync }, /* fsync */ 165 { &vop_seek_desc, procfs_seek }, /* seek */ 166 { &vop_remove_desc, procfs_remove }, /* remove */ 167 { &vop_link_desc, procfs_link }, /* link */ 168 { &vop_rename_desc, procfs_rename }, /* rename */ 169 { &vop_mkdir_desc, procfs_mkdir }, /* mkdir */ 170 { &vop_rmdir_desc, procfs_rmdir }, /* rmdir */ 171 { &vop_symlink_desc, procfs_symlink }, /* symlink */ 172 { &vop_readdir_desc, procfs_readdir }, /* readdir */ 173 { &vop_readlink_desc, procfs_readlink }, /* readlink */ 174 { &vop_abortop_desc, procfs_abortop }, /* abortop */ 175 { &vop_inactive_desc, procfs_inactive }, /* inactive */ 176 { &vop_reclaim_desc, procfs_reclaim }, /* reclaim */ 177 { &vop_lock_desc, procfs_lock }, /* lock */ 178 { &vop_unlock_desc, procfs_unlock }, /* unlock */ 179 { &vop_bmap_desc, procfs_bmap }, /* bmap */ 180 { &vop_strategy_desc, procfs_strategy }, /* strategy */ 181 { &vop_print_desc, procfs_print }, /* print */ 182 { &vop_islocked_desc, procfs_islocked }, /* islocked */ 183 { &vop_pathconf_desc, procfs_pathconf }, /* pathconf */ 184 { &vop_advlock_desc, procfs_advlock }, /* advlock */ 185 { &vop_blkatoff_desc, procfs_blkatoff }, /* blkatoff */ 186 { &vop_valloc_desc, procfs_valloc }, /* valloc */ 187 { &vop_vfree_desc, procfs_vfree }, /* vfree */ 188 { &vop_truncate_desc, procfs_truncate }, /* truncate */ 189 { &vop_update_desc, procfs_update }, /* update */ 190 { (struct vnodeop_desc*)NULL, (int(*) __P((void *)))NULL } 191 }; 192 struct vnodeopv_desc procfs_vnodeop_opv_desc = 193 { &procfs_vnodeop_p, procfs_vnodeop_entries }; 194 /* 195 * set things up for doing i/o on 196 * the pfsnode (vp). (vp) is locked 197 * on entry, and should be left locked 198 * on exit. 199 * 200 * for procfs we don't need to do anything 201 * in particular for i/o. all that is done 202 * is to support exclusive open on process 203 * memory images. 204 */ 205 int 206 procfs_open(v) 207 void *v; 208 { 209 struct vop_open_args /* { 210 struct vnode *a_vp; 211 int a_mode; 212 struct ucred *a_cred; 213 struct proc *a_p; 214 } */ *ap = v; 215 struct pfsnode *pfs = VTOPFS(ap->a_vp); 216 struct proc *p1, *p2; 217 int error; 218 219 p1 = ap->a_p; /* tracer */ 220 p2 = PFIND(pfs->pfs_pid); /* traced */ 221 222 if (p2 == NULL) 223 return (ENOENT); /* was ESRCH, jsp */ 224 225 switch (pfs->pfs_type) { 226 case Pmem: 227 if (((pfs->pfs_flags & FWRITE) && (ap->a_mode & O_EXCL)) || 228 ((pfs->pfs_flags & O_EXCL) && (ap->a_mode & FWRITE))) 229 return (EBUSY); 230 231 if ((error = procfs_checkioperm(p1, p2)) != 0) 232 return (EPERM); 233 234 if (ap->a_mode & FWRITE) 235 pfs->pfs_flags = ap->a_mode & (FWRITE|O_EXCL); 236 237 return (0); 238 239 default: 240 break; 241 } 242 243 return (0); 244 } 245 246 /* 247 * close the pfsnode (vp) after doing i/o. 248 * (vp) is not locked on entry or exit. 249 * 250 * nothing to do for procfs other than undo 251 * any exclusive open flag (see _open above). 252 */ 253 int 254 procfs_close(v) 255 void *v; 256 { 257 struct vop_close_args /* { 258 struct vnode *a_vp; 259 int a_fflag; 260 struct ucred *a_cred; 261 struct proc *a_p; 262 } */ *ap = v; 263 struct pfsnode *pfs = VTOPFS(ap->a_vp); 264 265 switch (pfs->pfs_type) { 266 case Pmem: 267 if ((ap->a_fflag & FWRITE) && (pfs->pfs_flags & O_EXCL)) 268 pfs->pfs_flags &= ~(FWRITE|O_EXCL); 269 break; 270 271 default: 272 break; 273 } 274 275 return (0); 276 } 277 278 /* 279 * do block mapping for pfsnode (vp). 280 * since we don't use the buffer cache 281 * for procfs this function should never 282 * be called. in any case, it's not clear 283 * what part of the kernel ever makes use 284 * of this function. for sanity, this is the 285 * usual no-op bmap, although returning 286 * (EIO) would be a reasonable alternative. 287 */ 288 int 289 procfs_bmap(v) 290 void *v; 291 { 292 struct vop_bmap_args /* { 293 struct vnode *a_vp; 294 daddr_t a_bn; 295 struct vnode **a_vpp; 296 daddr_t *a_bnp; 297 } */ *ap = v; 298 299 if (ap->a_vpp != NULL) 300 *ap->a_vpp = ap->a_vp; 301 if (ap->a_bnp != NULL) 302 *ap->a_bnp = ap->a_bn; 303 return (0); 304 } 305 306 /* 307 * _inactive is called when the pfsnode 308 * is vrele'd and the reference count goes 309 * to zero. (vp) will be on the vnode free 310 * list, so to get it back vget() must be 311 * used. 312 * 313 * for procfs, check if the process is still 314 * alive and if it isn't then just throw away 315 * the vnode by calling vgone(). this may 316 * be overkill and a waste of time since the 317 * chances are that the process will still be 318 * there and PFIND is not free. 319 * 320 * (vp) is not locked on entry or exit. 321 */ 322 int 323 procfs_inactive(v) 324 void *v; 325 { 326 struct vop_inactive_args /* { 327 struct vnode *a_vp; 328 } */ *ap = v; 329 struct pfsnode *pfs = VTOPFS(ap->a_vp); 330 331 if (PFIND(pfs->pfs_pid) == 0) 332 vgone(ap->a_vp); 333 334 return (0); 335 } 336 337 /* 338 * _reclaim is called when getnewvnode() 339 * wants to make use of an entry on the vnode 340 * free list. at this time the filesystem needs 341 * to free any private data and remove the node 342 * from any private lists. 343 */ 344 int 345 procfs_reclaim(v) 346 void *v; 347 { 348 struct vop_reclaim_args /* { 349 struct vnode *a_vp; 350 } */ *ap = v; 351 352 return (procfs_freevp(ap->a_vp)); 353 } 354 355 /* 356 * Return POSIX pathconf information applicable to special devices. 357 */ 358 int 359 procfs_pathconf(v) 360 void *v; 361 { 362 struct vop_pathconf_args /* { 363 struct vnode *a_vp; 364 int a_name; 365 register_t *a_retval; 366 } */ *ap = v; 367 368 switch (ap->a_name) { 369 case _PC_LINK_MAX: 370 *ap->a_retval = LINK_MAX; 371 return (0); 372 case _PC_MAX_CANON: 373 *ap->a_retval = MAX_CANON; 374 return (0); 375 case _PC_MAX_INPUT: 376 *ap->a_retval = MAX_INPUT; 377 return (0); 378 case _PC_PIPE_BUF: 379 *ap->a_retval = PIPE_BUF; 380 return (0); 381 case _PC_CHOWN_RESTRICTED: 382 *ap->a_retval = 1; 383 return (0); 384 case _PC_VDISABLE: 385 *ap->a_retval = _POSIX_VDISABLE; 386 return (0); 387 default: 388 return (EINVAL); 389 } 390 /* NOTREACHED */ 391 } 392 393 /* 394 * _print is used for debugging. 395 * just print a readable description 396 * of (vp). 397 */ 398 int 399 procfs_print(v) 400 void *v; 401 { 402 struct vop_print_args /* { 403 struct vnode *a_vp; 404 } */ *ap = v; 405 struct pfsnode *pfs = VTOPFS(ap->a_vp); 406 407 printf("tag VT_PROCFS, type %d, pid %d, mode %x, flags %lx\n", 408 pfs->pfs_type, pfs->pfs_pid, pfs->pfs_mode, pfs->pfs_flags); 409 return 0; 410 } 411 412 int 413 procfs_link(v) 414 void *v; 415 { 416 struct vop_link_args /* { 417 struct vnode *a_dvp; 418 struct vnode *a_vp; 419 struct componentname *a_cnp; 420 } */ *ap = v; 421 422 VOP_ABORTOP(ap->a_dvp, ap->a_cnp); 423 vput(ap->a_dvp); 424 return (EROFS); 425 } 426 427 int 428 procfs_symlink(v) 429 void *v; 430 { 431 struct vop_symlink_args /* { 432 struct vnode *a_dvp; 433 struct vnode **a_vpp; 434 struct componentname *a_cnp; 435 struct vattr *a_vap; 436 char *a_target; 437 } */ *ap = v; 438 439 VOP_ABORTOP(ap->a_dvp, ap->a_cnp); 440 vput(ap->a_dvp); 441 return (EROFS); 442 } 443 444 /* 445 * Invent attributes for pfsnode (vp) and store 446 * them in (vap). 447 * Directories lengths are returned as zero since 448 * any real length would require the genuine size 449 * to be computed, and nothing cares anyway. 450 * 451 * this is relatively minimal for procfs. 452 */ 453 int 454 procfs_getattr(v) 455 void *v; 456 { 457 struct vop_getattr_args /* { 458 struct vnode *a_vp; 459 struct vattr *a_vap; 460 struct ucred *a_cred; 461 struct proc *a_p; 462 } */ *ap = v; 463 struct pfsnode *pfs = VTOPFS(ap->a_vp); 464 struct vattr *vap = ap->a_vap; 465 struct proc *procp; 466 struct timeval tv; 467 int error; 468 469 /* first check the process still exists */ 470 switch (pfs->pfs_type) { 471 case Proot: 472 case Pcurproc: 473 procp = 0; 474 break; 475 476 default: 477 procp = PFIND(pfs->pfs_pid); 478 if (procp == 0) 479 return (ENOENT); 480 break; 481 } 482 483 error = 0; 484 485 /* start by zeroing out the attributes */ 486 VATTR_NULL(vap); 487 488 /* next do all the common fields */ 489 vap->va_type = ap->a_vp->v_type; 490 vap->va_mode = pfs->pfs_mode; 491 vap->va_fileid = pfs->pfs_fileno; 492 vap->va_flags = 0; 493 vap->va_blocksize = PAGE_SIZE; 494 495 /* 496 * Make all times be current TOD. 497 * It would be possible to get the process start 498 * time from the p_stat structure, but there's 499 * no "file creation" time stamp anyway, and the 500 * p_stat structure is not addressible if u. gets 501 * swapped out for that process. 502 */ 503 microtime(&tv); 504 TIMEVAL_TO_TIMESPEC(&tv, &vap->va_ctime); 505 vap->va_atime = vap->va_mtime = vap->va_ctime; 506 507 switch (pfs->pfs_type) { 508 case Pmem: 509 case Pregs: 510 case Pfpregs: 511 /* 512 * If the process has exercised some setuid or setgid 513 * privilege, then rip away read/write permission so 514 * that only root can gain access. 515 */ 516 if (procp->p_flag & P_SUGID) 517 vap->va_mode &= ~(S_IRUSR|S_IWUSR); 518 /* FALLTHROUGH */ 519 case Pctl: 520 case Pstatus: 521 case Pnote: 522 case Pnotepg: 523 vap->va_nlink = 1; 524 vap->va_uid = procp->p_ucred->cr_uid; 525 vap->va_gid = procp->p_ucred->cr_gid; 526 break; 527 528 default: 529 break; 530 } 531 532 /* 533 * now do the object specific fields 534 * 535 * The size could be set from struct reg, but it's hardly 536 * worth the trouble, and it puts some (potentially) machine 537 * dependent data into this machine-independent code. If it 538 * becomes important then this function should break out into 539 * a per-file stat function in the corresponding .c file. 540 */ 541 542 switch (pfs->pfs_type) { 543 case Proot: 544 /* 545 * Set nlink to 1 to tell fts(3) we don't actually know. 546 */ 547 vap->va_nlink = 1; 548 vap->va_uid = 0; 549 vap->va_gid = 0; 550 vap->va_bytes = vap->va_size = DEV_BSIZE; 551 break; 552 553 case Pcurproc: { 554 char buf[16]; /* should be enough */ 555 vap->va_nlink = 1; 556 vap->va_uid = 0; 557 vap->va_gid = 0; 558 vap->va_bytes = vap->va_size = 559 sprintf(buf, "%ld", (long)curproc->p_pid); 560 break; 561 } 562 563 case Pproc: 564 vap->va_nlink = 2; 565 vap->va_uid = procp->p_ucred->cr_uid; 566 vap->va_gid = procp->p_ucred->cr_gid; 567 vap->va_bytes = vap->va_size = DEV_BSIZE; 568 break; 569 570 case Pfile: 571 error = EOPNOTSUPP; 572 break; 573 574 case Pmem: 575 vap->va_bytes = vap->va_size = 576 ctob(procp->p_vmspace->vm_tsize + 577 procp->p_vmspace->vm_dsize + 578 procp->p_vmspace->vm_ssize); 579 break; 580 581 #if defined(PT_GETREGS) || defined(PT_SETREGS) 582 case Pregs: 583 vap->va_bytes = vap->va_size = sizeof(struct reg); 584 break; 585 #endif 586 587 #if defined(PT_GETFPREGS) || defined(PT_SETFPREGS) 588 case Pfpregs: 589 vap->va_bytes = vap->va_size = sizeof(struct fpreg); 590 break; 591 #endif 592 593 case Pctl: 594 case Pstatus: 595 case Pnote: 596 case Pnotepg: 597 vap->va_bytes = vap->va_size = 0; 598 break; 599 600 default: 601 panic("procfs_getattr"); 602 } 603 604 return (error); 605 } 606 607 /*ARGSUSED*/ 608 int 609 procfs_setattr(v) 610 void *v; 611 { 612 /* 613 * just fake out attribute setting 614 * it's not good to generate an error 615 * return, otherwise things like creat() 616 * will fail when they try to set the 617 * file length to 0. worse, this means 618 * that echo $note > /proc/$pid/note will fail. 619 */ 620 621 return (0); 622 } 623 624 /* 625 * implement access checking. 626 * 627 * actually, the check for super-user is slightly 628 * broken since it will allow read access to write-only 629 * objects. this doesn't cause any particular trouble 630 * but does mean that the i/o entry points need to check 631 * that the operation really does make sense. 632 */ 633 int 634 procfs_access(v) 635 void *v; 636 { 637 struct vop_access_args /* { 638 struct vnode *a_vp; 639 int a_mode; 640 struct ucred *a_cred; 641 struct proc *a_p; 642 } */ *ap = v; 643 struct vattr va; 644 int error; 645 646 if ((error = VOP_GETATTR(ap->a_vp, &va, ap->a_cred, ap->a_p)) != 0) 647 return (error); 648 649 return (vaccess(va.va_type, va.va_mode, 650 va.va_uid, va.va_gid, ap->a_mode, ap->a_cred)); 651 } 652 653 /* 654 * lookup. this is incredibly complicated in the 655 * general case, however for most pseudo-filesystems 656 * very little needs to be done. 657 * 658 * unless you want to get a migraine, just make sure your 659 * filesystem doesn't do any locking of its own. otherwise 660 * read and inwardly digest ufs_lookup(). 661 */ 662 int 663 procfs_lookup(v) 664 void *v; 665 { 666 struct vop_lookup_args /* { 667 struct vnode * a_dvp; 668 struct vnode ** a_vpp; 669 struct componentname * a_cnp; 670 } */ *ap = v; 671 struct componentname *cnp = ap->a_cnp; 672 struct vnode **vpp = ap->a_vpp; 673 struct vnode *dvp = ap->a_dvp; 674 const char *pname = cnp->cn_nameptr; 675 struct proc_target *pt; 676 struct vnode *fvp; 677 pid_t pid; 678 struct pfsnode *pfs; 679 struct proc *p; 680 int i; 681 682 *vpp = NULL; 683 684 if (cnp->cn_nameiop == DELETE || cnp->cn_nameiop == RENAME) 685 return (EROFS); 686 687 if (cnp->cn_namelen == 1 && *pname == '.') { 688 *vpp = dvp; 689 VREF(dvp); 690 /*VOP_LOCK(dvp);*/ 691 return (0); 692 } 693 694 pfs = VTOPFS(dvp); 695 switch (pfs->pfs_type) { 696 case Proot: 697 if (cnp->cn_flags & ISDOTDOT) 698 return (EIO); 699 700 if (CNEQ(cnp, "curproc", 7)) 701 return (procfs_allocvp(dvp->v_mount, vpp, 0, Pcurproc)); 702 703 pid = atopid(pname, cnp->cn_namelen); 704 if (pid == NO_PID) 705 break; 706 707 p = PFIND(pid); 708 if (p == 0) 709 break; 710 711 return (procfs_allocvp(dvp->v_mount, vpp, pid, Pproc)); 712 713 case Pproc: 714 if (cnp->cn_flags & ISDOTDOT) 715 return (procfs_root(dvp->v_mount, vpp)); 716 717 p = PFIND(pfs->pfs_pid); 718 if (p == 0) 719 break; 720 721 for (pt = proc_targets, i = 0; i < nproc_targets; pt++, i++) { 722 if (cnp->cn_namelen == pt->pt_namlen && 723 bcmp(pt->pt_name, pname, cnp->cn_namelen) == 0 && 724 (pt->pt_valid == NULL || (*pt->pt_valid)(p))) 725 goto found; 726 } 727 break; 728 729 found: 730 if (pt->pt_pfstype == Pfile) { 731 fvp = procfs_findtextvp(p); 732 /* We already checked that it exists. */ 733 VREF(fvp); 734 VOP_LOCK(fvp); 735 *vpp = fvp; 736 return (0); 737 } 738 739 return (procfs_allocvp(dvp->v_mount, vpp, pfs->pfs_pid, 740 pt->pt_pfstype)); 741 742 default: 743 return (ENOTDIR); 744 } 745 746 return (cnp->cn_nameiop == LOOKUP ? ENOENT : EROFS); 747 } 748 749 int 750 procfs_validfile(p) 751 struct proc *p; 752 { 753 754 return (procfs_findtextvp(p) != NULLVP); 755 } 756 757 /* 758 * readdir returns directory entries from pfsnode (vp). 759 * 760 * the strategy here with procfs is to generate a single 761 * directory entry at a time (struct dirent) and then 762 * copy that out to userland using uiomove. a more efficent 763 * though more complex implementation, would try to minimize 764 * the number of calls to uiomove(). for procfs, this is 765 * hardly worth the added code complexity. 766 * 767 * this should just be done through read() 768 */ 769 int 770 procfs_readdir(v) 771 void *v; 772 { 773 struct vop_readdir_args /* { 774 struct vnode *a_vp; 775 struct uio *a_uio; 776 struct ucred *a_cred; 777 int *a_eofflag; 778 off_t *a_cookies; 779 int a_ncookies; 780 } */ *ap = v; 781 struct uio *uio = ap->a_uio; 782 struct dirent d; 783 struct pfsnode *pfs; 784 int i; 785 int error; 786 off_t *cookies = ap->a_cookies; 787 int ncookies = ap->a_ncookies; 788 789 pfs = VTOPFS(ap->a_vp); 790 791 if (uio->uio_resid < UIO_MX) 792 return (EINVAL); 793 if (uio->uio_offset < 0) 794 return (EINVAL); 795 796 error = 0; 797 i = uio->uio_offset; 798 bzero((caddr_t)&d, UIO_MX); 799 d.d_reclen = UIO_MX; 800 801 switch (pfs->pfs_type) { 802 /* 803 * this is for the process-specific sub-directories. 804 * all that is needed to is copy out all the entries 805 * from the procent[] table (top of this file). 806 */ 807 case Pproc: { 808 struct proc *p; 809 struct proc_target *pt; 810 811 p = PFIND(pfs->pfs_pid); 812 if (p == NULL) 813 break; 814 815 for (pt = &proc_targets[i]; 816 uio->uio_resid >= UIO_MX && i < nproc_targets; pt++, i++) { 817 if (pt->pt_valid && (*pt->pt_valid)(p) == 0) 818 continue; 819 820 d.d_fileno = PROCFS_FILENO(pfs->pfs_pid, pt->pt_pfstype); 821 d.d_namlen = pt->pt_namlen; 822 bcopy(pt->pt_name, d.d_name, pt->pt_namlen + 1); 823 d.d_type = pt->pt_type; 824 825 if ((error = uiomove((caddr_t)&d, UIO_MX, uio)) != 0) 826 break; 827 if (ncookies-- > 0) 828 *cookies++ = i + 1; 829 } 830 831 break; 832 } 833 834 /* 835 * this is for the root of the procfs filesystem 836 * what is needed is a special entry for "curproc" 837 * followed by an entry for each process on allproc 838 #ifdef PROCFS_ZOMBIE 839 * and zombproc. 840 #endif 841 */ 842 843 case Proot: { 844 #ifdef PROCFS_ZOMBIE 845 int doingzomb = 0; 846 #endif 847 int pcnt = i; 848 volatile struct proc *p = allproc.lh_first; 849 850 if (pcnt > 3) 851 pcnt = 3; 852 #ifdef PROCFS_ZOMBIE 853 again: 854 #endif 855 for (; p && uio->uio_resid >= UIO_MX; i++, pcnt++) { 856 switch (i) { 857 case 0: /* `.' */ 858 case 1: /* `..' */ 859 d.d_fileno = PROCFS_FILENO(0, Proot); 860 d.d_namlen = i + 1; 861 bcopy("..", d.d_name, d.d_namlen); 862 d.d_name[i + 1] = '\0'; 863 d.d_type = DT_DIR; 864 break; 865 866 case 2: 867 d.d_fileno = PROCFS_FILENO(0, Pcurproc); 868 d.d_namlen = 7; 869 bcopy("curproc", d.d_name, 8); 870 d.d_type = DT_LNK; 871 break; 872 873 default: 874 while (pcnt < i) { 875 pcnt++; 876 p = p->p_list.le_next; 877 if (!p) 878 goto done; 879 } 880 d.d_fileno = PROCFS_FILENO(p->p_pid, Pproc); 881 d.d_namlen = sprintf(d.d_name, "%ld", 882 (long)p->p_pid); 883 d.d_type = DT_REG; 884 p = p->p_list.le_next; 885 break; 886 } 887 888 if ((error = uiomove((caddr_t)&d, UIO_MX, uio)) != 0) 889 break; 890 if (ncookies-- > 0) 891 *cookies++ = i + 1; 892 } 893 done: 894 895 #ifdef PROCFS_ZOMBIE 896 if (p == 0 && doingzomb == 0) { 897 doingzomb = 1; 898 p = zombproc.lh_first; 899 goto again; 900 } 901 #endif 902 903 break; 904 905 } 906 907 default: 908 error = ENOTDIR; 909 break; 910 } 911 912 uio->uio_offset = i; 913 return (error); 914 } 915 916 /* 917 * readlink reads the link of `curproc' 918 */ 919 int 920 procfs_readlink(v) 921 void *v; 922 { 923 struct vop_readlink_args *ap = v; 924 char buf[16]; /* should be enough */ 925 int len; 926 927 if (VTOPFS(ap->a_vp)->pfs_fileno != PROCFS_FILENO(0, Pcurproc)) 928 return (EINVAL); 929 930 len = sprintf(buf, "%ld", (long)curproc->p_pid); 931 932 return (uiomove((caddr_t)buf, len, ap->a_uio)); 933 } 934 935 /* 936 * convert decimal ascii to pid_t 937 */ 938 static pid_t 939 atopid(b, len) 940 const char *b; 941 u_int len; 942 { 943 pid_t p = 0; 944 945 while (len--) { 946 char c = *b++; 947 if (c < '0' || c > '9') 948 return (NO_PID); 949 p = 10 * p + (c - '0'); 950 if (p > PID_MAX) 951 return (NO_PID); 952 } 953 954 return (p); 955 } 956