1 /*- 2 * Copyright (c) 2001 Dag-Erling Co�dan Sm�rgrav 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer 10 * in this position and unchanged. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 3. The name of the author may not be used to endorse or promote products 15 * derived from this software without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 */ 28 29 #include <sys/cdefs.h> 30 __FBSDID("$FreeBSD$"); 31 32 #include "opt_pseudofs.h" 33 34 #include <sys/param.h> 35 #include <sys/kernel.h> 36 #include <sys/systm.h> 37 #include <sys/ctype.h> 38 #include <sys/dirent.h> 39 #include <sys/fcntl.h> 40 #include <sys/limits.h> 41 #include <sys/lock.h> 42 #include <sys/malloc.h> 43 #include <sys/mount.h> 44 #include <sys/mutex.h> 45 #include <sys/namei.h> 46 #include <sys/proc.h> 47 #include <sys/sbuf.h> 48 #include <sys/sx.h> 49 #include <sys/sysctl.h> 50 #include <sys/vnode.h> 51 52 #include <fs/pseudofs/pseudofs.h> 53 #include <fs/pseudofs/pseudofs_internal.h> 54 55 #define KASSERT_PN_IS_DIR(pn) \ 56 KASSERT((pn)->pn_type == pfstype_root || \ 57 (pn)->pn_type == pfstype_dir || \ 58 (pn)->pn_type == pfstype_procdir, \ 59 ("%s(): VDIR vnode refers to non-directory pfs_node", __func__)) 60 61 #define KASSERT_PN_IS_FILE(pn) \ 62 KASSERT((pn)->pn_type == pfstype_file, \ 63 ("%s(): VREG vnode refers to non-file pfs_node", __func__)) 64 65 #define KASSERT_PN_IS_LINK(pn) \ 66 KASSERT((pn)->pn_type == pfstype_symlink, \ 67 ("%s(): VLNK vnode refers to non-link pfs_node", __func__)) 68 69 /* 70 * Returns the fileno, adjusted for target pid 71 */ 72 static uint32_t 73 pn_fileno(struct pfs_node *pn, pid_t pid) 74 { 75 76 KASSERT(pn->pn_fileno > 0, 77 ("%s(): no fileno allocated", __func__)); 78 if (pid != NO_PID) 79 return (pn->pn_fileno * NO_PID + pid); 80 return (pn->pn_fileno); 81 } 82 83 /* 84 * Returns non-zero if given file is visible to given thread. 85 */ 86 static int 87 pfs_visible_proc(struct thread *td, struct pfs_node *pn, struct proc *proc) 88 { 89 int visible; 90 91 if (proc == NULL) 92 return (0); 93 94 PROC_LOCK_ASSERT(proc, MA_OWNED); 95 96 visible = ((proc->p_flag & P_WEXIT) == 0); 97 if (visible) 98 visible = (p_cansee(td, proc) == 0); 99 if (visible && pn->pn_vis != NULL) 100 visible = pn_vis(td, proc, pn); 101 if (!visible) 102 return (0); 103 return (1); 104 } 105 106 static int 107 pfs_visible(struct thread *td, struct pfs_node *pn, pid_t pid, struct proc **p) 108 { 109 struct proc *proc; 110 111 PFS_TRACE(("%s (pid: %d, req: %d)", 112 pn->pn_name, pid, td->td_proc->p_pid)); 113 114 if (p) 115 *p = NULL; 116 if (pid == NO_PID) 117 PFS_RETURN (1); 118 if ((proc = pfind(pid)) == NULL) 119 PFS_RETURN (0); 120 if (pfs_visible_proc(td, pn, proc)) { 121 if (p) 122 *p = proc; 123 else 124 PROC_UNLOCK(proc); 125 PFS_RETURN (1); 126 } 127 PROC_UNLOCK(proc); 128 PFS_RETURN (0); 129 } 130 131 /* 132 * Verify permissions 133 */ 134 static int 135 pfs_access(struct vop_access_args *va) 136 { 137 struct vnode *vn = va->a_vp; 138 struct pfs_vdata *pvd = vn->v_data; 139 struct vattr vattr; 140 int error; 141 142 PFS_TRACE(("%s", pvd->pvd_pn->pn_name)); 143 (void)pvd; 144 145 error = VOP_GETATTR(vn, &vattr, va->a_cred); 146 if (error) 147 PFS_RETURN (error); 148 error = vaccess(vn->v_type, vattr.va_mode, vattr.va_uid, 149 vattr.va_gid, va->a_accmode, va->a_cred, NULL); 150 PFS_RETURN (error); 151 } 152 153 /* 154 * Close a file or directory 155 */ 156 static int 157 pfs_close(struct vop_close_args *va) 158 { 159 struct vnode *vn = va->a_vp; 160 struct pfs_vdata *pvd = vn->v_data; 161 struct pfs_node *pn = pvd->pvd_pn; 162 struct proc *proc; 163 int error; 164 165 PFS_TRACE(("%s", pn->pn_name)); 166 pfs_assert_not_owned(pn); 167 168 /* 169 * Do nothing unless this is the last close and the node has a 170 * last-close handler. 171 */ 172 if (vrefcnt(vn) > 1 || pn->pn_close == NULL) 173 PFS_RETURN (0); 174 175 if (pvd->pvd_pid != NO_PID) { 176 proc = pfind(pvd->pvd_pid); 177 } else { 178 proc = NULL; 179 } 180 181 error = pn_close(va->a_td, proc, pn); 182 183 if (proc != NULL) 184 PROC_UNLOCK(proc); 185 186 PFS_RETURN (error); 187 } 188 189 /* 190 * Get file attributes 191 */ 192 static int 193 pfs_getattr(struct vop_getattr_args *va) 194 { 195 struct vnode *vn = va->a_vp; 196 struct pfs_vdata *pvd = vn->v_data; 197 struct pfs_node *pn = pvd->pvd_pn; 198 struct vattr *vap = va->a_vap; 199 struct proc *proc; 200 int error = 0; 201 202 PFS_TRACE(("%s", pn->pn_name)); 203 pfs_assert_not_owned(pn); 204 205 if (!pfs_visible(curthread, pn, pvd->pvd_pid, &proc)) 206 PFS_RETURN (ENOENT); 207 208 vap->va_type = vn->v_type; 209 vap->va_fileid = pn_fileno(pn, pvd->pvd_pid); 210 vap->va_flags = 0; 211 vap->va_blocksize = PAGE_SIZE; 212 vap->va_bytes = vap->va_size = 0; 213 vap->va_filerev = 0; 214 vap->va_fsid = vn->v_mount->mnt_stat.f_fsid.val[0]; 215 vap->va_nlink = 1; 216 nanotime(&vap->va_ctime); 217 vap->va_atime = vap->va_mtime = vap->va_ctime; 218 219 switch (pn->pn_type) { 220 case pfstype_procdir: 221 case pfstype_root: 222 case pfstype_dir: 223 #if 0 224 pfs_lock(pn); 225 /* compute link count */ 226 pfs_unlock(pn); 227 #endif 228 vap->va_mode = 0555; 229 break; 230 case pfstype_file: 231 case pfstype_symlink: 232 vap->va_mode = 0444; 233 break; 234 default: 235 printf("shouldn't be here!\n"); 236 vap->va_mode = 0; 237 break; 238 } 239 240 if (proc != NULL) { 241 vap->va_uid = proc->p_ucred->cr_ruid; 242 vap->va_gid = proc->p_ucred->cr_rgid; 243 } else { 244 vap->va_uid = 0; 245 vap->va_gid = 0; 246 } 247 248 if (pn->pn_attr != NULL) 249 error = pn_attr(curthread, proc, pn, vap); 250 251 if(proc != NULL) 252 PROC_UNLOCK(proc); 253 254 PFS_RETURN (error); 255 } 256 257 /* 258 * Perform an ioctl 259 */ 260 static int 261 pfs_ioctl(struct vop_ioctl_args *va) 262 { 263 struct vnode *vn; 264 struct pfs_vdata *pvd; 265 struct pfs_node *pn; 266 struct proc *proc; 267 int error; 268 269 vn = va->a_vp; 270 vn_lock(vn, LK_SHARED | LK_RETRY); 271 if (vn->v_iflag & VI_DOOMED) { 272 VOP_UNLOCK(vn, 0); 273 return (EBADF); 274 } 275 pvd = vn->v_data; 276 pn = pvd->pvd_pn; 277 278 PFS_TRACE(("%s: %lx", pn->pn_name, va->a_command)); 279 pfs_assert_not_owned(pn); 280 281 if (vn->v_type != VREG) { 282 VOP_UNLOCK(vn, 0); 283 PFS_RETURN (EINVAL); 284 } 285 KASSERT_PN_IS_FILE(pn); 286 287 if (pn->pn_ioctl == NULL) { 288 VOP_UNLOCK(vn, 0); 289 PFS_RETURN (ENOTTY); 290 } 291 292 /* 293 * This is necessary because process' privileges may 294 * have changed since the open() call. 295 */ 296 if (!pfs_visible(curthread, pn, pvd->pvd_pid, &proc)) { 297 VOP_UNLOCK(vn, 0); 298 PFS_RETURN (EIO); 299 } 300 301 error = pn_ioctl(curthread, proc, pn, va->a_command, va->a_data); 302 303 if (proc != NULL) 304 PROC_UNLOCK(proc); 305 306 VOP_UNLOCK(vn, 0); 307 PFS_RETURN (error); 308 } 309 310 /* 311 * Perform getextattr 312 */ 313 static int 314 pfs_getextattr(struct vop_getextattr_args *va) 315 { 316 struct vnode *vn = va->a_vp; 317 struct pfs_vdata *pvd = vn->v_data; 318 struct pfs_node *pn = pvd->pvd_pn; 319 struct proc *proc; 320 int error; 321 322 PFS_TRACE(("%s", pn->pn_name)); 323 pfs_assert_not_owned(pn); 324 325 /* 326 * This is necessary because either process' privileges may 327 * have changed since the open() call. 328 */ 329 if (!pfs_visible(curthread, pn, pvd->pvd_pid, &proc)) 330 PFS_RETURN (EIO); 331 332 if (pn->pn_getextattr == NULL) 333 error = EOPNOTSUPP; 334 else 335 error = pn_getextattr(curthread, proc, pn, 336 va->a_attrnamespace, va->a_name, va->a_uio, 337 va->a_size, va->a_cred); 338 339 if (proc != NULL) 340 PROC_UNLOCK(proc); 341 342 PFS_RETURN (error); 343 } 344 345 /* 346 * Convert a vnode to its component name 347 */ 348 static int 349 pfs_vptocnp(struct vop_vptocnp_args *ap) 350 { 351 struct vnode *vp = ap->a_vp; 352 struct vnode **dvp = ap->a_vpp; 353 struct pfs_vdata *pvd = vp->v_data; 354 struct pfs_node *pd = pvd->pvd_pn; 355 struct pfs_node *pn; 356 struct mount *mp; 357 char *buf = ap->a_buf; 358 int *buflen = ap->a_buflen; 359 char pidbuf[PFS_NAMELEN]; 360 pid_t pid = pvd->pvd_pid; 361 int len, i, error, locked; 362 363 i = *buflen; 364 error = 0; 365 366 pfs_lock(pd); 367 368 if (vp->v_type == VDIR && pd->pn_type == pfstype_root) { 369 *dvp = vp; 370 vhold(*dvp); 371 pfs_unlock(pd); 372 PFS_RETURN (0); 373 } else if (vp->v_type == VDIR && pd->pn_type == pfstype_procdir) { 374 len = snprintf(pidbuf, sizeof(pidbuf), "%d", pid); 375 i -= len; 376 if (i < 0) { 377 error = ENOMEM; 378 goto failed; 379 } 380 bcopy(pidbuf, buf + i, len); 381 } else { 382 len = strlen(pd->pn_name); 383 i -= len; 384 if (i < 0) { 385 error = ENOMEM; 386 goto failed; 387 } 388 bcopy(pd->pn_name, buf + i, len); 389 } 390 391 pn = pd->pn_parent; 392 pfs_unlock(pd); 393 394 mp = vp->v_mount; 395 error = vfs_busy(mp, 0); 396 if (error) 397 return (error); 398 399 /* 400 * vp is held by caller. 401 */ 402 locked = VOP_ISLOCKED(vp); 403 VOP_UNLOCK(vp, 0); 404 405 error = pfs_vncache_alloc(mp, dvp, pn, pid); 406 if (error) { 407 vn_lock(vp, locked | LK_RETRY); 408 vfs_unbusy(mp); 409 PFS_RETURN(error); 410 } 411 412 *buflen = i; 413 VOP_UNLOCK(*dvp, 0); 414 vn_lock(vp, locked | LK_RETRY); 415 vfs_unbusy(mp); 416 417 PFS_RETURN (0); 418 failed: 419 pfs_unlock(pd); 420 PFS_RETURN(error); 421 } 422 423 /* 424 * Look up a file or directory 425 */ 426 static int 427 pfs_lookup(struct vop_cachedlookup_args *va) 428 { 429 struct vnode *vn = va->a_dvp; 430 struct vnode **vpp = va->a_vpp; 431 struct componentname *cnp = va->a_cnp; 432 struct pfs_vdata *pvd = vn->v_data; 433 struct pfs_node *pd = pvd->pvd_pn; 434 struct pfs_node *pn, *pdn = NULL; 435 pid_t pid = pvd->pvd_pid; 436 char *pname; 437 int error, i, namelen, visible; 438 439 PFS_TRACE(("%.*s", (int)cnp->cn_namelen, cnp->cn_nameptr)); 440 pfs_assert_not_owned(pd); 441 442 if (vn->v_type != VDIR) 443 PFS_RETURN (ENOTDIR); 444 KASSERT_PN_IS_DIR(pd); 445 446 error = VOP_ACCESS(vn, VEXEC, cnp->cn_cred, cnp->cn_thread); 447 if (error) 448 PFS_RETURN (error); 449 450 /* 451 * Don't support DELETE or RENAME. CREATE is supported so 452 * that O_CREAT will work, but the lookup will still fail if 453 * the file does not exist. 454 */ 455 if ((cnp->cn_flags & ISLASTCN) && 456 (cnp->cn_nameiop == DELETE || cnp->cn_nameiop == RENAME)) 457 PFS_RETURN (EOPNOTSUPP); 458 459 /* shortcut: check if the name is too long */ 460 if (cnp->cn_namelen >= PFS_NAMELEN) 461 PFS_RETURN (ENOENT); 462 463 /* check that parent directory is visible... */ 464 if (!pfs_visible(curthread, pd, pvd->pvd_pid, NULL)) 465 PFS_RETURN (ENOENT); 466 467 /* self */ 468 namelen = cnp->cn_namelen; 469 pname = cnp->cn_nameptr; 470 if (namelen == 1 && pname[0] == '.') { 471 pn = pd; 472 *vpp = vn; 473 VREF(vn); 474 PFS_RETURN (0); 475 } 476 477 /* parent */ 478 if (cnp->cn_flags & ISDOTDOT) { 479 if (pd->pn_type == pfstype_root) 480 PFS_RETURN (EIO); 481 VOP_UNLOCK(vn, 0); 482 KASSERT(pd->pn_parent != NULL, 483 ("%s(): non-root directory has no parent", __func__)); 484 /* 485 * This one is tricky. Descendents of procdir nodes 486 * inherit their parent's process affinity, but 487 * there's no easy reverse mapping. For simplicity, 488 * we assume that if this node is a procdir, its 489 * parent isn't (which is correct as long as 490 * descendents of procdir nodes are never procdir 491 * nodes themselves) 492 */ 493 if (pd->pn_type == pfstype_procdir) 494 pid = NO_PID; 495 pfs_lock(pd); 496 pn = pd->pn_parent; 497 pfs_unlock(pd); 498 goto got_pnode; 499 } 500 501 pfs_lock(pd); 502 503 /* named node */ 504 for (pn = pd->pn_nodes; pn != NULL; pn = pn->pn_next) 505 if (pn->pn_type == pfstype_procdir) 506 pdn = pn; 507 else if (pn->pn_name[namelen] == '\0' && 508 bcmp(pname, pn->pn_name, namelen) == 0) { 509 pfs_unlock(pd); 510 goto got_pnode; 511 } 512 513 /* process dependent node */ 514 if ((pn = pdn) != NULL) { 515 pid = 0; 516 for (pid = 0, i = 0; i < namelen && isdigit(pname[i]); ++i) 517 if ((pid = pid * 10 + pname[i] - '0') > PID_MAX) 518 break; 519 if (i == cnp->cn_namelen) { 520 pfs_unlock(pd); 521 goto got_pnode; 522 } 523 } 524 525 pfs_unlock(pd); 526 527 PFS_RETURN (ENOENT); 528 529 got_pnode: 530 pfs_assert_not_owned(pd); 531 pfs_assert_not_owned(pn); 532 visible = pfs_visible(curthread, pn, pid, NULL); 533 if (!visible) { 534 error = ENOENT; 535 goto failed; 536 } 537 538 error = pfs_vncache_alloc(vn->v_mount, vpp, pn, pid); 539 if (error) 540 goto failed; 541 542 if (cnp->cn_flags & ISDOTDOT) 543 vn_lock(vn, LK_EXCLUSIVE|LK_RETRY); 544 if (cnp->cn_flags & MAKEENTRY && !(vn->v_iflag & VI_DOOMED)) 545 cache_enter(vn, *vpp, cnp); 546 PFS_RETURN (0); 547 failed: 548 if (cnp->cn_flags & ISDOTDOT) 549 vn_lock(vn, LK_EXCLUSIVE|LK_RETRY); 550 PFS_RETURN(error); 551 } 552 553 /* 554 * Open a file or directory. 555 */ 556 static int 557 pfs_open(struct vop_open_args *va) 558 { 559 struct vnode *vn = va->a_vp; 560 struct pfs_vdata *pvd = vn->v_data; 561 struct pfs_node *pn = pvd->pvd_pn; 562 int mode = va->a_mode; 563 564 PFS_TRACE(("%s (mode 0x%x)", pn->pn_name, mode)); 565 pfs_assert_not_owned(pn); 566 567 /* check if the requested mode is permitted */ 568 if (((mode & FREAD) && !(mode & PFS_RD)) || 569 ((mode & FWRITE) && !(mode & PFS_WR))) 570 PFS_RETURN (EPERM); 571 572 /* we don't support locking */ 573 if ((mode & O_SHLOCK) || (mode & O_EXLOCK)) 574 PFS_RETURN (EOPNOTSUPP); 575 576 PFS_RETURN (0); 577 } 578 579 /* 580 * Read from a file 581 */ 582 static int 583 pfs_read(struct vop_read_args *va) 584 { 585 struct vnode *vn = va->a_vp; 586 struct pfs_vdata *pvd = vn->v_data; 587 struct pfs_node *pn = pvd->pvd_pn; 588 struct uio *uio = va->a_uio; 589 struct proc *proc; 590 struct sbuf *sb = NULL; 591 int error, locked; 592 unsigned int buflen, offset, resid; 593 594 PFS_TRACE(("%s", pn->pn_name)); 595 pfs_assert_not_owned(pn); 596 597 if (vn->v_type != VREG) 598 PFS_RETURN (EINVAL); 599 KASSERT_PN_IS_FILE(pn); 600 601 if (!(pn->pn_flags & PFS_RD)) 602 PFS_RETURN (EBADF); 603 604 if (pn->pn_fill == NULL) 605 PFS_RETURN (EIO); 606 607 /* 608 * This is necessary because either process' privileges may 609 * have changed since the open() call. 610 */ 611 if (!pfs_visible(curthread, pn, pvd->pvd_pid, &proc)) 612 PFS_RETURN (EIO); 613 if (proc != NULL) { 614 _PHOLD(proc); 615 PROC_UNLOCK(proc); 616 } 617 618 vhold(vn); 619 locked = VOP_ISLOCKED(vn); 620 VOP_UNLOCK(vn, 0); 621 622 if (pn->pn_flags & PFS_RAWRD) { 623 PFS_TRACE(("%zd resid", uio->uio_resid)); 624 error = pn_fill(curthread, proc, pn, NULL, uio); 625 PFS_TRACE(("%zd resid", uio->uio_resid)); 626 goto ret; 627 } 628 629 /* beaucoup sanity checks so we don't ask for bogus allocation */ 630 if (uio->uio_offset < 0 || uio->uio_resid < 0 || 631 (offset = uio->uio_offset) != uio->uio_offset || 632 (resid = uio->uio_resid) != uio->uio_resid || 633 (buflen = offset + resid) < offset || buflen >= INT_MAX) { 634 error = EINVAL; 635 goto ret; 636 } 637 if (buflen > MAXPHYS) 638 buflen = MAXPHYS; 639 640 sb = sbuf_new(sb, NULL, buflen + 1, 0); 641 if (sb == NULL) { 642 error = EIO; 643 goto ret; 644 } 645 646 error = pn_fill(curthread, proc, pn, sb, uio); 647 648 if (error) { 649 sbuf_delete(sb); 650 goto ret; 651 } 652 653 /* 654 * XXX: If the buffer overflowed, sbuf_len() will not return 655 * the data length. Then just use the full length because an 656 * overflowed sbuf must be full. 657 */ 658 if (sbuf_finish(sb) == 0) 659 buflen = sbuf_len(sb); 660 error = uiomove_frombuf(sbuf_data(sb), buflen, uio); 661 sbuf_delete(sb); 662 ret: 663 vn_lock(vn, locked | LK_RETRY); 664 vdrop(vn); 665 if (proc != NULL) 666 PRELE(proc); 667 PFS_RETURN (error); 668 } 669 670 /* 671 * Iterate through directory entries 672 */ 673 static int 674 pfs_iterate(struct thread *td, struct proc *proc, struct pfs_node *pd, 675 struct pfs_node **pn, struct proc **p) 676 { 677 int visible; 678 679 sx_assert(&allproc_lock, SX_SLOCKED); 680 pfs_assert_owned(pd); 681 again: 682 if (*pn == NULL) { 683 /* first node */ 684 *pn = pd->pn_nodes; 685 } else if ((*pn)->pn_type != pfstype_procdir) { 686 /* next node */ 687 *pn = (*pn)->pn_next; 688 } 689 if (*pn != NULL && (*pn)->pn_type == pfstype_procdir) { 690 /* next process */ 691 if (*p == NULL) 692 *p = LIST_FIRST(&allproc); 693 else 694 *p = LIST_NEXT(*p, p_list); 695 /* out of processes: next node */ 696 if (*p == NULL) 697 *pn = (*pn)->pn_next; 698 else 699 PROC_LOCK(*p); 700 } 701 702 if ((*pn) == NULL) 703 return (-1); 704 705 if (*p != NULL) { 706 visible = pfs_visible_proc(td, *pn, *p); 707 PROC_UNLOCK(*p); 708 } else if (proc != NULL) { 709 visible = pfs_visible_proc(td, *pn, proc); 710 } else { 711 visible = 1; 712 } 713 if (!visible) 714 goto again; 715 716 return (0); 717 } 718 719 /* Directory entry list */ 720 struct pfsentry { 721 STAILQ_ENTRY(pfsentry) link; 722 struct dirent entry; 723 }; 724 STAILQ_HEAD(pfsdirentlist, pfsentry); 725 726 /* 727 * Return directory entries. 728 */ 729 static int 730 pfs_readdir(struct vop_readdir_args *va) 731 { 732 struct vnode *vn = va->a_vp; 733 struct pfs_vdata *pvd = vn->v_data; 734 struct pfs_node *pd = pvd->pvd_pn; 735 pid_t pid = pvd->pvd_pid; 736 struct proc *p, *proc; 737 struct pfs_node *pn; 738 struct uio *uio; 739 struct pfsentry *pfsent, *pfsent2; 740 struct pfsdirentlist lst; 741 off_t offset; 742 int error, i, resid; 743 744 STAILQ_INIT(&lst); 745 error = 0; 746 KASSERT(pd->pn_info == vn->v_mount->mnt_data, 747 ("%s(): pn_info does not match mountpoint", __func__)); 748 PFS_TRACE(("%s pid %lu", pd->pn_name, (unsigned long)pid)); 749 pfs_assert_not_owned(pd); 750 751 if (vn->v_type != VDIR) 752 PFS_RETURN (ENOTDIR); 753 KASSERT_PN_IS_DIR(pd); 754 uio = va->a_uio; 755 756 /* only allow reading entire entries */ 757 offset = uio->uio_offset; 758 resid = uio->uio_resid; 759 if (offset < 0 || offset % PFS_DELEN != 0 || 760 (resid && resid < PFS_DELEN)) 761 PFS_RETURN (EINVAL); 762 if (resid == 0) 763 PFS_RETURN (0); 764 765 sx_slock(&allproc_lock); 766 pfs_lock(pd); 767 768 /* check if the directory is visible to the caller */ 769 if (!pfs_visible(curthread, pd, pid, &proc)) { 770 sx_sunlock(&allproc_lock); 771 pfs_unlock(pd); 772 PFS_RETURN (ENOENT); 773 } 774 KASSERT(pid == NO_PID || proc != NULL, 775 ("%s(): no process for pid %lu", __func__, (unsigned long)pid)); 776 777 /* skip unwanted entries */ 778 for (pn = NULL, p = NULL; offset > 0; offset -= PFS_DELEN) { 779 if (pfs_iterate(curthread, proc, pd, &pn, &p) == -1) { 780 /* nothing left... */ 781 if (proc != NULL) 782 PROC_UNLOCK(proc); 783 pfs_unlock(pd); 784 sx_sunlock(&allproc_lock); 785 PFS_RETURN (0); 786 } 787 } 788 789 /* fill in entries */ 790 while (pfs_iterate(curthread, proc, pd, &pn, &p) != -1 && 791 resid >= PFS_DELEN) { 792 if ((pfsent = malloc(sizeof(struct pfsentry), M_IOV, 793 M_NOWAIT | M_ZERO)) == NULL) { 794 error = ENOMEM; 795 break; 796 } 797 pfsent->entry.d_reclen = PFS_DELEN; 798 pfsent->entry.d_fileno = pn_fileno(pn, pid); 799 /* PFS_DELEN was picked to fit PFS_NAMLEN */ 800 for (i = 0; i < PFS_NAMELEN - 1 && pn->pn_name[i] != '\0'; ++i) 801 pfsent->entry.d_name[i] = pn->pn_name[i]; 802 pfsent->entry.d_name[i] = 0; 803 pfsent->entry.d_namlen = i; 804 switch (pn->pn_type) { 805 case pfstype_procdir: 806 KASSERT(p != NULL, 807 ("reached procdir node with p == NULL")); 808 pfsent->entry.d_namlen = snprintf(pfsent->entry.d_name, 809 PFS_NAMELEN, "%d", p->p_pid); 810 /* fall through */ 811 case pfstype_root: 812 case pfstype_dir: 813 case pfstype_this: 814 case pfstype_parent: 815 pfsent->entry.d_type = DT_DIR; 816 break; 817 case pfstype_file: 818 pfsent->entry.d_type = DT_REG; 819 break; 820 case pfstype_symlink: 821 pfsent->entry.d_type = DT_LNK; 822 break; 823 default: 824 panic("%s has unexpected node type: %d", pn->pn_name, pn->pn_type); 825 } 826 PFS_TRACE(("%s", pfsent->entry.d_name)); 827 STAILQ_INSERT_TAIL(&lst, pfsent, link); 828 offset += PFS_DELEN; 829 resid -= PFS_DELEN; 830 } 831 if (proc != NULL) 832 PROC_UNLOCK(proc); 833 pfs_unlock(pd); 834 sx_sunlock(&allproc_lock); 835 i = 0; 836 STAILQ_FOREACH_SAFE(pfsent, &lst, link, pfsent2) { 837 if (error == 0) 838 error = uiomove(&pfsent->entry, PFS_DELEN, uio); 839 free(pfsent, M_IOV); 840 i++; 841 } 842 PFS_TRACE(("%d bytes", i * PFS_DELEN)); 843 PFS_RETURN (error); 844 } 845 846 /* 847 * Read a symbolic link 848 */ 849 static int 850 pfs_readlink(struct vop_readlink_args *va) 851 { 852 struct vnode *vn = va->a_vp; 853 struct pfs_vdata *pvd = vn->v_data; 854 struct pfs_node *pn = pvd->pvd_pn; 855 struct uio *uio = va->a_uio; 856 struct proc *proc = NULL; 857 char buf[PATH_MAX]; 858 struct sbuf sb; 859 int error, locked; 860 861 PFS_TRACE(("%s", pn->pn_name)); 862 pfs_assert_not_owned(pn); 863 864 if (vn->v_type != VLNK) 865 PFS_RETURN (EINVAL); 866 KASSERT_PN_IS_LINK(pn); 867 868 if (pn->pn_fill == NULL) 869 PFS_RETURN (EIO); 870 871 if (pvd->pvd_pid != NO_PID) { 872 if ((proc = pfind(pvd->pvd_pid)) == NULL) 873 PFS_RETURN (EIO); 874 if (proc->p_flag & P_WEXIT) { 875 PROC_UNLOCK(proc); 876 PFS_RETURN (EIO); 877 } 878 _PHOLD(proc); 879 PROC_UNLOCK(proc); 880 } 881 vhold(vn); 882 locked = VOP_ISLOCKED(vn); 883 VOP_UNLOCK(vn, 0); 884 885 /* sbuf_new() can't fail with a static buffer */ 886 sbuf_new(&sb, buf, sizeof buf, 0); 887 888 error = pn_fill(curthread, proc, pn, &sb, NULL); 889 890 if (proc != NULL) 891 PRELE(proc); 892 vn_lock(vn, locked | LK_RETRY); 893 vdrop(vn); 894 895 if (error) { 896 sbuf_delete(&sb); 897 PFS_RETURN (error); 898 } 899 900 if (sbuf_finish(&sb) != 0) { 901 sbuf_delete(&sb); 902 PFS_RETURN (ENAMETOOLONG); 903 } 904 905 error = uiomove_frombuf(sbuf_data(&sb), sbuf_len(&sb), uio); 906 sbuf_delete(&sb); 907 PFS_RETURN (error); 908 } 909 910 /* 911 * Reclaim a vnode 912 */ 913 static int 914 pfs_reclaim(struct vop_reclaim_args *va) 915 { 916 struct vnode *vn = va->a_vp; 917 struct pfs_vdata *pvd = vn->v_data; 918 struct pfs_node *pn = pvd->pvd_pn; 919 920 PFS_TRACE(("%s", pn->pn_name)); 921 pfs_assert_not_owned(pn); 922 923 return (pfs_vncache_free(va->a_vp)); 924 } 925 926 /* 927 * Set attributes 928 */ 929 static int 930 pfs_setattr(struct vop_setattr_args *va) 931 { 932 struct vnode *vn = va->a_vp; 933 struct pfs_vdata *pvd = vn->v_data; 934 struct pfs_node *pn = pvd->pvd_pn; 935 936 PFS_TRACE(("%s", pn->pn_name)); 937 pfs_assert_not_owned(pn); 938 939 PFS_RETURN (EOPNOTSUPP); 940 } 941 942 /* 943 * Write to a file 944 */ 945 static int 946 pfs_write(struct vop_write_args *va) 947 { 948 struct vnode *vn = va->a_vp; 949 struct pfs_vdata *pvd = vn->v_data; 950 struct pfs_node *pn = pvd->pvd_pn; 951 struct uio *uio = va->a_uio; 952 struct proc *proc; 953 struct sbuf sb; 954 int error; 955 956 PFS_TRACE(("%s", pn->pn_name)); 957 pfs_assert_not_owned(pn); 958 959 if (vn->v_type != VREG) 960 PFS_RETURN (EINVAL); 961 KASSERT_PN_IS_FILE(pn); 962 963 if (!(pn->pn_flags & PFS_WR)) 964 PFS_RETURN (EBADF); 965 966 if (pn->pn_fill == NULL) 967 PFS_RETURN (EIO); 968 969 /* 970 * This is necessary because either process' privileges may 971 * have changed since the open() call. 972 */ 973 if (!pfs_visible(curthread, pn, pvd->pvd_pid, &proc)) 974 PFS_RETURN (EIO); 975 if (proc != NULL) { 976 _PHOLD(proc); 977 PROC_UNLOCK(proc); 978 } 979 980 if (pn->pn_flags & PFS_RAWWR) { 981 error = pn_fill(curthread, proc, pn, NULL, uio); 982 if (proc != NULL) 983 PRELE(proc); 984 PFS_RETURN (error); 985 } 986 987 sbuf_uionew(&sb, uio, &error); 988 if (error) { 989 if (proc != NULL) 990 PRELE(proc); 991 PFS_RETURN (error); 992 } 993 994 error = pn_fill(curthread, proc, pn, &sb, uio); 995 996 sbuf_delete(&sb); 997 if (proc != NULL) 998 PRELE(proc); 999 PFS_RETURN (error); 1000 } 1001 1002 /* 1003 * Vnode operations 1004 */ 1005 struct vop_vector pfs_vnodeops = { 1006 .vop_default = &default_vnodeops, 1007 1008 .vop_access = pfs_access, 1009 .vop_cachedlookup = pfs_lookup, 1010 .vop_close = pfs_close, 1011 .vop_create = VOP_EOPNOTSUPP, 1012 .vop_getattr = pfs_getattr, 1013 .vop_getextattr = pfs_getextattr, 1014 .vop_ioctl = pfs_ioctl, 1015 .vop_link = VOP_EOPNOTSUPP, 1016 .vop_lookup = vfs_cache_lookup, 1017 .vop_mkdir = VOP_EOPNOTSUPP, 1018 .vop_mknod = VOP_EOPNOTSUPP, 1019 .vop_open = pfs_open, 1020 .vop_read = pfs_read, 1021 .vop_readdir = pfs_readdir, 1022 .vop_readlink = pfs_readlink, 1023 .vop_reclaim = pfs_reclaim, 1024 .vop_remove = VOP_EOPNOTSUPP, 1025 .vop_rename = VOP_EOPNOTSUPP, 1026 .vop_rmdir = VOP_EOPNOTSUPP, 1027 .vop_setattr = pfs_setattr, 1028 .vop_symlink = VOP_EOPNOTSUPP, 1029 .vop_vptocnp = pfs_vptocnp, 1030 .vop_write = pfs_write, 1031 /* XXX I've probably forgotten a few that need VOP_EOPNOTSUPP */ 1032 }; 1033