pseudofs_vnops.c revision 227550
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: head/sys/fs/pseudofs/pseudofs_vnops.c 227550 2011-11-16 10:11:55Z pho $"); 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 */ 72static uint32_t 73pn_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 */ 86static int 87pfs_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 106static int 107pfs_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 */ 134static int 135pfs_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 */ 156static int 157pfs_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 */ 192static int 193pfs_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 */ 260static int 261pfs_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 */ 313static int 314pfs_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 */ 348static int 349pfs_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 vhold(*dvp); 414 vput(*dvp); 415 vn_lock(vp, locked | LK_RETRY); 416 vfs_unbusy(mp); 417 418 PFS_RETURN (0); 419failed: 420 pfs_unlock(pd); 421 PFS_RETURN(error); 422} 423 424/* 425 * Look up a file or directory 426 */ 427static int 428pfs_lookup(struct vop_cachedlookup_args *va) 429{ 430 struct vnode *vn = va->a_dvp; 431 struct vnode **vpp = va->a_vpp; 432 struct componentname *cnp = va->a_cnp; 433 struct pfs_vdata *pvd = vn->v_data; 434 struct pfs_node *pd = pvd->pvd_pn; 435 struct pfs_node *pn, *pdn = NULL; 436 pid_t pid = pvd->pvd_pid; 437 char *pname; 438 int error, i, namelen, visible; 439 440 PFS_TRACE(("%.*s", (int)cnp->cn_namelen, cnp->cn_nameptr)); 441 pfs_assert_not_owned(pd); 442 443 if (vn->v_type != VDIR) 444 PFS_RETURN (ENOTDIR); 445 KASSERT_PN_IS_DIR(pd); 446 447 error = VOP_ACCESS(vn, VEXEC, cnp->cn_cred, cnp->cn_thread); 448 if (error) 449 PFS_RETURN (error); 450 451 /* 452 * Don't support DELETE or RENAME. CREATE is supported so 453 * that O_CREAT will work, but the lookup will still fail if 454 * the file does not exist. 455 */ 456 if ((cnp->cn_flags & ISLASTCN) && 457 (cnp->cn_nameiop == DELETE || cnp->cn_nameiop == RENAME)) 458 PFS_RETURN (EOPNOTSUPP); 459 460 /* shortcut: check if the name is too long */ 461 if (cnp->cn_namelen >= PFS_NAMELEN) 462 PFS_RETURN (ENOENT); 463 464 /* check that parent directory is visible... */ 465 if (!pfs_visible(curthread, pd, pvd->pvd_pid, NULL)) 466 PFS_RETURN (ENOENT); 467 468 /* self */ 469 namelen = cnp->cn_namelen; 470 pname = cnp->cn_nameptr; 471 if (namelen == 1 && pname[0] == '.') { 472 pn = pd; 473 *vpp = vn; 474 VREF(vn); 475 PFS_RETURN (0); 476 } 477 478 /* parent */ 479 if (cnp->cn_flags & ISDOTDOT) { 480 if (pd->pn_type == pfstype_root) 481 PFS_RETURN (EIO); 482 VOP_UNLOCK(vn, 0); 483 KASSERT(pd->pn_parent != NULL, 484 ("%s(): non-root directory has no parent", __func__)); 485 /* 486 * This one is tricky. Descendents of procdir nodes 487 * inherit their parent's process affinity, but 488 * there's no easy reverse mapping. For simplicity, 489 * we assume that if this node is a procdir, its 490 * parent isn't (which is correct as long as 491 * descendents of procdir nodes are never procdir 492 * nodes themselves) 493 */ 494 if (pd->pn_type == pfstype_procdir) 495 pid = NO_PID; 496 pfs_lock(pd); 497 pn = pd->pn_parent; 498 pfs_unlock(pd); 499 goto got_pnode; 500 } 501 502 pfs_lock(pd); 503 504 /* named node */ 505 for (pn = pd->pn_nodes; pn != NULL; pn = pn->pn_next) 506 if (pn->pn_type == pfstype_procdir) 507 pdn = pn; 508 else if (pn->pn_name[namelen] == '\0' && 509 bcmp(pname, pn->pn_name, namelen) == 0) { 510 pfs_unlock(pd); 511 goto got_pnode; 512 } 513 514 /* process dependent node */ 515 if ((pn = pdn) != NULL) { 516 pid = 0; 517 for (pid = 0, i = 0; i < namelen && isdigit(pname[i]); ++i) 518 if ((pid = pid * 10 + pname[i] - '0') > PID_MAX) 519 break; 520 if (i == cnp->cn_namelen) { 521 pfs_unlock(pd); 522 goto got_pnode; 523 } 524 } 525 526 pfs_unlock(pd); 527 528 PFS_RETURN (ENOENT); 529 530 got_pnode: 531 pfs_assert_not_owned(pd); 532 pfs_assert_not_owned(pn); 533 visible = pfs_visible(curthread, pn, pid, NULL); 534 if (!visible) { 535 error = ENOENT; 536 goto failed; 537 } 538 539 error = pfs_vncache_alloc(vn->v_mount, vpp, pn, pid); 540 if (error) 541 goto failed; 542 543 if (cnp->cn_flags & ISDOTDOT) 544 vn_lock(vn, LK_EXCLUSIVE|LK_RETRY); 545 if (cnp->cn_flags & MAKEENTRY && !(vn->v_iflag & VI_DOOMED)) 546 cache_enter(vn, *vpp, cnp); 547 PFS_RETURN (0); 548 failed: 549 if (cnp->cn_flags & ISDOTDOT) 550 vn_lock(vn, LK_EXCLUSIVE|LK_RETRY); 551 PFS_RETURN(error); 552} 553 554/* 555 * Open a file or directory. 556 */ 557static int 558pfs_open(struct vop_open_args *va) 559{ 560 struct vnode *vn = va->a_vp; 561 struct pfs_vdata *pvd = vn->v_data; 562 struct pfs_node *pn = pvd->pvd_pn; 563 int mode = va->a_mode; 564 565 PFS_TRACE(("%s (mode 0x%x)", pn->pn_name, mode)); 566 pfs_assert_not_owned(pn); 567 568 /* check if the requested mode is permitted */ 569 if (((mode & FREAD) && !(mode & PFS_RD)) || 570 ((mode & FWRITE) && !(mode & PFS_WR))) 571 PFS_RETURN (EPERM); 572 573 /* we don't support locking */ 574 if ((mode & O_SHLOCK) || (mode & O_EXLOCK)) 575 PFS_RETURN (EOPNOTSUPP); 576 577 PFS_RETURN (0); 578} 579 580/* 581 * Read from a file 582 */ 583static int 584pfs_read(struct vop_read_args *va) 585{ 586 struct vnode *vn = va->a_vp; 587 struct pfs_vdata *pvd = vn->v_data; 588 struct pfs_node *pn = pvd->pvd_pn; 589 struct uio *uio = va->a_uio; 590 struct proc *proc; 591 struct sbuf *sb = NULL; 592 int error, locked; 593 unsigned int buflen, offset, resid; 594 595 PFS_TRACE(("%s", pn->pn_name)); 596 pfs_assert_not_owned(pn); 597 598 if (vn->v_type != VREG) 599 PFS_RETURN (EINVAL); 600 KASSERT_PN_IS_FILE(pn); 601 602 if (!(pn->pn_flags & PFS_RD)) 603 PFS_RETURN (EBADF); 604 605 if (pn->pn_fill == NULL) 606 PFS_RETURN (EIO); 607 608 /* 609 * This is necessary because either process' privileges may 610 * have changed since the open() call. 611 */ 612 if (!pfs_visible(curthread, pn, pvd->pvd_pid, &proc)) 613 PFS_RETURN (EIO); 614 if (proc != NULL) { 615 _PHOLD(proc); 616 PROC_UNLOCK(proc); 617 } 618 619 vhold(vn); 620 locked = VOP_ISLOCKED(vn); 621 VOP_UNLOCK(vn, 0); 622 623 if (pn->pn_flags & PFS_RAWRD) { 624 PFS_TRACE(("%zd resid", uio->uio_resid)); 625 error = pn_fill(curthread, proc, pn, NULL, uio); 626 PFS_TRACE(("%zd resid", uio->uio_resid)); 627 goto ret; 628 } 629 630 /* beaucoup sanity checks so we don't ask for bogus allocation */ 631 if (uio->uio_offset < 0 || uio->uio_resid < 0 || 632 (offset = uio->uio_offset) != uio->uio_offset || 633 (resid = uio->uio_resid) != uio->uio_resid || 634 (buflen = offset + resid + 1) < offset || buflen > INT_MAX) { 635 error = EINVAL; 636 goto ret; 637 } 638 if (buflen > MAXPHYS + 1) 639 buflen = MAXPHYS + 1; 640 641 sb = sbuf_new(sb, NULL, buflen, 0); 642 if (sb == NULL) { 643 error = EIO; 644 goto ret; 645 } 646 647 error = pn_fill(curthread, proc, pn, sb, uio); 648 649 if (error) { 650 sbuf_delete(sb); 651 goto ret; 652 } 653 654 sbuf_finish(sb); 655 error = uiomove_frombuf(sbuf_data(sb), sbuf_len(sb), uio); 656 sbuf_delete(sb); 657ret: 658 vn_lock(vn, locked | LK_RETRY); 659 vdrop(vn); 660 if (proc != NULL) 661 PRELE(proc); 662 PFS_RETURN (error); 663} 664 665/* 666 * Iterate through directory entries 667 */ 668static int 669pfs_iterate(struct thread *td, struct proc *proc, struct pfs_node *pd, 670 struct pfs_node **pn, struct proc **p) 671{ 672 int visible; 673 674 sx_assert(&allproc_lock, SX_SLOCKED); 675 pfs_assert_owned(pd); 676 again: 677 if (*pn == NULL) { 678 /* first node */ 679 *pn = pd->pn_nodes; 680 } else if ((*pn)->pn_type != pfstype_procdir) { 681 /* next node */ 682 *pn = (*pn)->pn_next; 683 } 684 if (*pn != NULL && (*pn)->pn_type == pfstype_procdir) { 685 /* next process */ 686 if (*p == NULL) 687 *p = LIST_FIRST(&allproc); 688 else 689 *p = LIST_NEXT(*p, p_list); 690 /* out of processes: next node */ 691 if (*p == NULL) 692 *pn = (*pn)->pn_next; 693 else 694 PROC_LOCK(*p); 695 } 696 697 if ((*pn) == NULL) 698 return (-1); 699 700 if (*p != NULL) { 701 visible = pfs_visible_proc(td, *pn, *p); 702 PROC_UNLOCK(*p); 703 } else if (proc != NULL) { 704 visible = pfs_visible_proc(td, *pn, proc); 705 } else { 706 visible = 1; 707 } 708 if (!visible) 709 goto again; 710 711 return (0); 712} 713 714/* Directory entry list */ 715struct pfsentry { 716 STAILQ_ENTRY(pfsentry) link; 717 struct dirent entry; 718}; 719STAILQ_HEAD(pfsdirentlist, pfsentry); 720 721/* 722 * Return directory entries. 723 */ 724static int 725pfs_readdir(struct vop_readdir_args *va) 726{ 727 struct vnode *vn = va->a_vp; 728 struct pfs_vdata *pvd = vn->v_data; 729 struct pfs_node *pd = pvd->pvd_pn; 730 pid_t pid = pvd->pvd_pid; 731 struct proc *p, *proc; 732 struct pfs_node *pn; 733 struct uio *uio; 734 struct pfsentry *pfsent, *pfsent2; 735 struct pfsdirentlist lst; 736 off_t offset; 737 int error, i, resid; 738 739 STAILQ_INIT(&lst); 740 error = 0; 741 KASSERT(pd->pn_info == vn->v_mount->mnt_data, 742 ("%s(): pn_info does not match mountpoint", __func__)); 743 PFS_TRACE(("%s pid %lu", pd->pn_name, (unsigned long)pid)); 744 pfs_assert_not_owned(pd); 745 746 if (vn->v_type != VDIR) 747 PFS_RETURN (ENOTDIR); 748 KASSERT_PN_IS_DIR(pd); 749 uio = va->a_uio; 750 751 /* only allow reading entire entries */ 752 offset = uio->uio_offset; 753 resid = uio->uio_resid; 754 if (offset < 0 || offset % PFS_DELEN != 0 || 755 (resid && resid < PFS_DELEN)) 756 PFS_RETURN (EINVAL); 757 if (resid == 0) 758 PFS_RETURN (0); 759 760 sx_slock(&allproc_lock); 761 pfs_lock(pd); 762 763 /* check if the directory is visible to the caller */ 764 if (!pfs_visible(curthread, pd, pid, &proc)) { 765 sx_sunlock(&allproc_lock); 766 pfs_unlock(pd); 767 PFS_RETURN (ENOENT); 768 } 769 KASSERT(pid == NO_PID || proc != NULL, 770 ("%s(): no process for pid %lu", __func__, (unsigned long)pid)); 771 772 /* skip unwanted entries */ 773 for (pn = NULL, p = NULL; offset > 0; offset -= PFS_DELEN) { 774 if (pfs_iterate(curthread, proc, pd, &pn, &p) == -1) { 775 /* nothing left... */ 776 if (proc != NULL) 777 PROC_UNLOCK(proc); 778 pfs_unlock(pd); 779 sx_sunlock(&allproc_lock); 780 PFS_RETURN (0); 781 } 782 } 783 784 /* fill in entries */ 785 while (pfs_iterate(curthread, proc, pd, &pn, &p) != -1 && 786 resid >= PFS_DELEN) { 787 if ((pfsent = malloc(sizeof(struct pfsentry), M_IOV, 788 M_NOWAIT | M_ZERO)) == NULL) { 789 error = ENOMEM; 790 break; 791 } 792 pfsent->entry.d_reclen = PFS_DELEN; 793 pfsent->entry.d_fileno = pn_fileno(pn, pid); 794 /* PFS_DELEN was picked to fit PFS_NAMLEN */ 795 for (i = 0; i < PFS_NAMELEN - 1 && pn->pn_name[i] != '\0'; ++i) 796 pfsent->entry.d_name[i] = pn->pn_name[i]; 797 pfsent->entry.d_name[i] = 0; 798 pfsent->entry.d_namlen = i; 799 switch (pn->pn_type) { 800 case pfstype_procdir: 801 KASSERT(p != NULL, 802 ("reached procdir node with p == NULL")); 803 pfsent->entry.d_namlen = snprintf(pfsent->entry.d_name, 804 PFS_NAMELEN, "%d", p->p_pid); 805 /* fall through */ 806 case pfstype_root: 807 case pfstype_dir: 808 case pfstype_this: 809 case pfstype_parent: 810 pfsent->entry.d_type = DT_DIR; 811 break; 812 case pfstype_file: 813 pfsent->entry.d_type = DT_REG; 814 break; 815 case pfstype_symlink: 816 pfsent->entry.d_type = DT_LNK; 817 break; 818 default: 819 panic("%s has unexpected node type: %d", pn->pn_name, pn->pn_type); 820 } 821 PFS_TRACE(("%s", pfsent->entry.d_name)); 822 STAILQ_INSERT_TAIL(&lst, pfsent, link); 823 offset += PFS_DELEN; 824 resid -= PFS_DELEN; 825 } 826 if (proc != NULL) 827 PROC_UNLOCK(proc); 828 pfs_unlock(pd); 829 sx_sunlock(&allproc_lock); 830 i = 0; 831 STAILQ_FOREACH_SAFE(pfsent, &lst, link, pfsent2) { 832 if (error == 0) 833 error = uiomove(&pfsent->entry, PFS_DELEN, uio); 834 free(pfsent, M_IOV); 835 i++; 836 } 837 PFS_TRACE(("%zd bytes", i * PFS_DELEN)); 838 PFS_RETURN (error); 839} 840 841/* 842 * Read a symbolic link 843 */ 844static int 845pfs_readlink(struct vop_readlink_args *va) 846{ 847 struct vnode *vn = va->a_vp; 848 struct pfs_vdata *pvd = vn->v_data; 849 struct pfs_node *pn = pvd->pvd_pn; 850 struct uio *uio = va->a_uio; 851 struct proc *proc = NULL; 852 char buf[PATH_MAX]; 853 struct sbuf sb; 854 int error, locked; 855 856 PFS_TRACE(("%s", pn->pn_name)); 857 pfs_assert_not_owned(pn); 858 859 if (vn->v_type != VLNK) 860 PFS_RETURN (EINVAL); 861 KASSERT_PN_IS_LINK(pn); 862 863 if (pn->pn_fill == NULL) 864 PFS_RETURN (EIO); 865 866 if (pvd->pvd_pid != NO_PID) { 867 if ((proc = pfind(pvd->pvd_pid)) == NULL) 868 PFS_RETURN (EIO); 869 if (proc->p_flag & P_WEXIT) { 870 PROC_UNLOCK(proc); 871 PFS_RETURN (EIO); 872 } 873 _PHOLD(proc); 874 PROC_UNLOCK(proc); 875 } 876 vhold(vn); 877 locked = VOP_ISLOCKED(vn); 878 VOP_UNLOCK(vn, 0); 879 880 /* sbuf_new() can't fail with a static buffer */ 881 sbuf_new(&sb, buf, sizeof buf, 0); 882 883 error = pn_fill(curthread, proc, pn, &sb, NULL); 884 885 if (proc != NULL) 886 PRELE(proc); 887 vn_lock(vn, locked | LK_RETRY); 888 vdrop(vn); 889 890 if (error) { 891 sbuf_delete(&sb); 892 PFS_RETURN (error); 893 } 894 895 sbuf_finish(&sb); 896 error = uiomove_frombuf(sbuf_data(&sb), sbuf_len(&sb), uio); 897 sbuf_delete(&sb); 898 PFS_RETURN (error); 899} 900 901/* 902 * Reclaim a vnode 903 */ 904static int 905pfs_reclaim(struct vop_reclaim_args *va) 906{ 907 struct vnode *vn = va->a_vp; 908 struct pfs_vdata *pvd = vn->v_data; 909 struct pfs_node *pn = pvd->pvd_pn; 910 911 PFS_TRACE(("%s", pn->pn_name)); 912 pfs_assert_not_owned(pn); 913 914 return (pfs_vncache_free(va->a_vp)); 915} 916 917/* 918 * Set attributes 919 */ 920static int 921pfs_setattr(struct vop_setattr_args *va) 922{ 923 struct vnode *vn = va->a_vp; 924 struct pfs_vdata *pvd = vn->v_data; 925 struct pfs_node *pn = pvd->pvd_pn; 926 927 PFS_TRACE(("%s", pn->pn_name)); 928 pfs_assert_not_owned(pn); 929 930 PFS_RETURN (EOPNOTSUPP); 931} 932 933/* 934 * Write to a file 935 */ 936static int 937pfs_write(struct vop_write_args *va) 938{ 939 struct vnode *vn = va->a_vp; 940 struct pfs_vdata *pvd = vn->v_data; 941 struct pfs_node *pn = pvd->pvd_pn; 942 struct uio *uio = va->a_uio; 943 struct proc *proc; 944 struct sbuf sb; 945 int error; 946 947 PFS_TRACE(("%s", pn->pn_name)); 948 pfs_assert_not_owned(pn); 949 950 if (vn->v_type != VREG) 951 PFS_RETURN (EINVAL); 952 KASSERT_PN_IS_FILE(pn); 953 954 if (!(pn->pn_flags & PFS_WR)) 955 PFS_RETURN (EBADF); 956 957 if (pn->pn_fill == NULL) 958 PFS_RETURN (EIO); 959 960 /* 961 * This is necessary because either process' privileges may 962 * have changed since the open() call. 963 */ 964 if (!pfs_visible(curthread, pn, pvd->pvd_pid, &proc)) 965 PFS_RETURN (EIO); 966 if (proc != NULL) { 967 _PHOLD(proc); 968 PROC_UNLOCK(proc); 969 } 970 971 if (pn->pn_flags & PFS_RAWWR) { 972 error = pn_fill(curthread, proc, pn, NULL, uio); 973 if (proc != NULL) 974 PRELE(proc); 975 PFS_RETURN (error); 976 } 977 978 sbuf_uionew(&sb, uio, &error); 979 if (error) { 980 if (proc != NULL) 981 PRELE(proc); 982 PFS_RETURN (error); 983 } 984 985 error = pn_fill(curthread, proc, pn, &sb, uio); 986 987 sbuf_delete(&sb); 988 if (proc != NULL) 989 PRELE(proc); 990 PFS_RETURN (error); 991} 992 993/* 994 * Vnode operations 995 */ 996struct vop_vector pfs_vnodeops = { 997 .vop_default = &default_vnodeops, 998 999 .vop_access = pfs_access, 1000 .vop_cachedlookup = pfs_lookup, 1001 .vop_close = pfs_close, 1002 .vop_create = VOP_EOPNOTSUPP, 1003 .vop_getattr = pfs_getattr, 1004 .vop_getextattr = pfs_getextattr, 1005 .vop_ioctl = pfs_ioctl, 1006 .vop_link = VOP_EOPNOTSUPP, 1007 .vop_lookup = vfs_cache_lookup, 1008 .vop_mkdir = VOP_EOPNOTSUPP, 1009 .vop_mknod = VOP_EOPNOTSUPP, 1010 .vop_open = pfs_open, 1011 .vop_read = pfs_read, 1012 .vop_readdir = pfs_readdir, 1013 .vop_readlink = pfs_readlink, 1014 .vop_reclaim = pfs_reclaim, 1015 .vop_remove = VOP_EOPNOTSUPP, 1016 .vop_rename = VOP_EOPNOTSUPP, 1017 .vop_rmdir = VOP_EOPNOTSUPP, 1018 .vop_setattr = pfs_setattr, 1019 .vop_symlink = VOP_EOPNOTSUPP, 1020 .vop_vptocnp = pfs_vptocnp, 1021 .vop_write = pfs_write, 1022 /* XXX I've probably forgotten a few that need VOP_EOPNOTSUPP */ 1023}; 1024