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 * $FreeBSD$ 29 */ 30 31 #include <sys/param.h> 32 #include <sys/kernel.h> 33 #include <sys/systm.h> 34 #include <sys/ctype.h> 35 #include <sys/dirent.h> 36 #include <sys/fcntl.h> 37 #include <sys/lock.h> 38 #include <sys/mount.h> 39 #include <sys/mutex.h> 40 #include <sys/namei.h> 41 #include <sys/proc.h> 42 #include <sys/sbuf.h> 43 #include <sys/sx.h> 44 #include <sys/sysctl.h> 45 #include <sys/vnode.h> 46 47 #include <fs/pseudofs/pseudofs.h> 48 #include <fs/pseudofs/pseudofs_internal.h> 49 50 #if 0 51 #define PFS_TRACE(foo) \ 52 do { \ 53 printf("pseudofs: %s(): line %d: ", __func__, __LINE__); \ 54 printf foo ; \ 55 printf("\n"); \ 56 } while (0) 57 #define PFS_RETURN(err) \ 58 do { \ 59 printf("pseudofs: %s(): line %d: returning %d\n", \ 60 __func__, __LINE__, err); \ 61 return (err); \ 62 } while (0) 63 #else 64 #define PFS_TRACE(foo) \ 65 do { /* nothing */ } while (0) 66 #define PFS_RETURN(err) \ 67 return (err) 68 #endif 69 70 /* 71 * Returns non-zero if given file is visible to given process 72 */ 73 static int 74 pfs_visible(struct thread *td, struct pfs_node *pn, pid_t pid) 75 { 76 struct proc *proc; 77 int r; 78 79 PFS_TRACE(("%s (pid: %d, req: %d)", 80 pn->pn_name, pid, td->td_proc->p_pid)); 81 82 if (pn->pn_flags & PFS_DISABLED) 83 PFS_RETURN (0); 84 85 r = 1; 86 if (pid != NO_PID) { 87 if ((proc = pfind(pid)) == NULL) 88 PFS_RETURN (0); 89 if (p_cansee(td, proc) != 0 || 90 (pn->pn_vis != NULL && !(pn->pn_vis)(td, proc, pn))) 91 r = 0; 92 PROC_UNLOCK(proc); 93 } 94 PFS_RETURN (r); 95 } 96 97 /* 98 * Verify permissions 99 */ 100 static int 101 pfs_access(struct vop_access_args *va) 102 { 103 struct vnode *vn = va->a_vp; 104 struct vattr vattr; 105 int error; 106 107 PFS_TRACE((((struct pfs_vdata *)vn->v_data)->pvd_pn->pn_name)); 108 109 error = VOP_GETATTR(vn, &vattr, va->a_cred, va->a_td); 110 if (error) 111 PFS_RETURN (error); 112 error = vaccess(vn->v_type, vattr.va_mode, vattr.va_uid, 113 vattr.va_gid, va->a_mode, va->a_cred, NULL); 114 PFS_RETURN (error); 115 } 116 117 /* 118 * Close a file or directory 119 */ 120 static int 121 pfs_close(struct vop_close_args *va) 122 { 123 struct vnode *vn = va->a_vp; 124 struct pfs_vdata *pvd = (struct pfs_vdata *)vn->v_data; 125 struct pfs_node *pn = pvd->pvd_pn; 126 struct proc *proc; 127 int error; 128 129 PFS_TRACE((pn->pn_name)); 130 131 /* 132 * Do nothing unless this is the last close and the node has a 133 * last-close handler. 134 */ 135 if (vrefcnt(vn) > 1 || pn->pn_close == NULL) 136 PFS_RETURN (0); 137 138 if (pvd->pvd_pid != NO_PID) 139 proc = pfind(pvd->pvd_pid); 140 else 141 proc = NULL; 142 143 error = (pn->pn_close)(va->a_td, proc, pn); 144 145 if (proc != NULL) 146 PROC_UNLOCK(proc); 147 148 PFS_RETURN (error); 149 } 150 151 /* 152 * Get file attributes 153 */ 154 static int 155 pfs_getattr(struct vop_getattr_args *va) 156 { 157 struct vnode *vn = va->a_vp; 158 struct pfs_vdata *pvd = (struct pfs_vdata *)vn->v_data; 159 struct pfs_node *pn = pvd->pvd_pn; 160 struct vattr *vap = va->a_vap; 161 struct proc *proc; 162 int error = 0; 163 164 PFS_TRACE((pn->pn_name)); 165 166 VATTR_NULL(vap); 167 vap->va_type = vn->v_type; 168 vap->va_fileid = pn->pn_fileno; 169 vap->va_flags = 0; 170 vap->va_blocksize = PAGE_SIZE; 171 vap->va_bytes = vap->va_size = 0; 172 vap->va_fsid = vn->v_mount->mnt_stat.f_fsid.val[0]; 173 vap->va_nlink = 1; 174 nanotime(&vap->va_ctime); 175 vap->va_atime = vap->va_mtime = vap->va_ctime; 176 177 switch (pn->pn_type) { 178 case pfstype_procdir: 179 case pfstype_root: 180 case pfstype_dir: 181 vap->va_mode = 0555; 182 break; 183 case pfstype_file: 184 case pfstype_symlink: 185 vap->va_mode = 0444; 186 break; 187 default: 188 printf("shouldn't be here!\n"); 189 vap->va_mode = 0; 190 break; 191 } 192 193 if (pvd->pvd_pid != NO_PID) { 194 if ((proc = pfind(pvd->pvd_pid)) == NULL) 195 PFS_RETURN (ENOENT); 196 vap->va_uid = proc->p_ucred->cr_ruid; 197 vap->va_gid = proc->p_ucred->cr_rgid; 198 if (pn->pn_attr != NULL) 199 error = (pn->pn_attr)(va->a_td, proc, pn, vap); 200 PROC_UNLOCK(proc); 201 } else { 202 vap->va_uid = 0; 203 vap->va_gid = 0; 204 } 205 206 PFS_RETURN (error); 207 } 208 209 /* 210 * Perform an ioctl 211 */ 212 static int 213 pfs_ioctl(struct vop_ioctl_args *va) 214 { 215 struct vnode *vn = va->a_vp; 216 struct pfs_vdata *pvd = (struct pfs_vdata *)vn->v_data; 217 struct pfs_node *pn = pvd->pvd_pn; 218 struct proc *proc = NULL; 219 int error; 220 221 PFS_TRACE(("%s: %lx", pn->pn_name, va->a_command)); 222 223 if (vn->v_type != VREG) 224 PFS_RETURN (EINVAL); 225 226 if (pn->pn_ioctl == NULL) 227 PFS_RETURN (ENOTTY); 228 229 /* 230 * This is necessary because either process' privileges may 231 * have changed since the open() call. 232 */ 233 if (!pfs_visible(curthread, pn, pvd->pvd_pid)) 234 PFS_RETURN (EIO); 235 236 /* XXX duplicates bits of pfs_visible() */ 237 if (pvd->pvd_pid != NO_PID) { 238 if ((proc = pfind(pvd->pvd_pid)) == NULL) 239 PFS_RETURN (EIO); 240 _PHOLD(proc); 241 PROC_UNLOCK(proc); 242 } 243 244 error = (pn->pn_ioctl)(curthread, proc, pn, va->a_command, va->a_data); 245 246 if (proc != NULL) 247 PRELE(proc); 248 249 PFS_RETURN (error); 250 } 251 252 /* 253 * Perform getextattr 254 */ 255 static int 256 pfs_getextattr(struct vop_getextattr_args *va) 257 { 258 struct vnode *vn = va->a_vp; 259 struct pfs_vdata *pvd = (struct pfs_vdata *)vn->v_data; 260 struct pfs_node *pn = pvd->pvd_pn; 261 struct proc *proc = NULL; 262 int error; 263 264 PFS_TRACE((pd->pn_name)); 265 266 if (pn->pn_getextattr == NULL) 267 PFS_RETURN (EOPNOTSUPP); 268 269 /* 270 * This is necessary because either process' privileges may 271 * have changed since the open() call. 272 */ 273 if (!pfs_visible(curthread, pn, pvd->pvd_pid)) 274 PFS_RETURN (EIO); 275 276 /* XXX duplicates bits of pfs_visible() */ 277 if (pvd->pvd_pid != NO_PID) { 278 if ((proc = pfind(pvd->pvd_pid)) == NULL) 279 PFS_RETURN (EIO); 280 _PHOLD(proc); 281 PROC_UNLOCK(proc); 282 } 283 284 error = (pn->pn_getextattr)(curthread, proc, pn, va->a_attrnamespace, 285 va->a_name, va->a_uio, va->a_size, va->a_cred); 286 287 if (proc != NULL) 288 PRELE(proc); 289 290 PFS_RETURN (error); 291 } 292 293 /* 294 * Look up a file or directory 295 * 296 * XXX NOTE! pfs_lookup() has been hooked into vop_lookup_desc! This 297 * will result in a lookup operation for a vnode which may already be 298 * cached, therefore we have to be careful to purge the VFS cache when 299 * reusing a vnode. 300 * 301 * This code will work, but is not really correct. Normally we would hook 302 * vfs_cache_lookup() into vop_lookup_desc and hook pfs_lookup() into 303 * vop_cachedlookup_desc. 304 */ 305 static int 306 pfs_lookup(struct vop_lookup_args *va) 307 { 308 struct vnode *vn = va->a_dvp; 309 struct vnode **vpp = va->a_vpp; 310 struct componentname *cnp = va->a_cnp; 311 struct pfs_vdata *pvd = (struct pfs_vdata *)vn->v_data; 312 struct pfs_node *pd = pvd->pvd_pn; 313 struct pfs_node *pn, *pdn = NULL; 314 pid_t pid = pvd->pvd_pid; 315 int lockparent; 316 int wantparent; 317 char *pname; 318 int error, i, namelen; 319 320 PFS_TRACE(("%.*s", (int)cnp->cn_namelen, cnp->cn_nameptr)); 321 322 cnp->cn_flags &= ~PDIRUNLOCK; 323 324 if (vn->v_type != VDIR) 325 PFS_RETURN (ENOTDIR); 326 327 /* 328 * Don't support DELETE or RENAME. CREATE is supported so 329 * that O_CREAT will work, but the lookup will still fail if 330 * the file does not exist. 331 */ 332 if (cnp->cn_nameiop == DELETE || cnp->cn_nameiop == RENAME) 333 PFS_RETURN (EOPNOTSUPP); 334 335 /* shortcut: check if the name is too long */ 336 if (cnp->cn_namelen >= PFS_NAMELEN) 337 PFS_RETURN (ENOENT); 338 339 /* check that parent directory is visisble... */ 340 if (!pfs_visible(curthread, pd, pvd->pvd_pid)) 341 PFS_RETURN (ENOENT); 342 343 lockparent = cnp->cn_flags & LOCKPARENT; 344 wantparent = cnp->cn_flags & (LOCKPARENT | WANTPARENT); 345 346 347 /* self */ 348 namelen = cnp->cn_namelen; 349 pname = cnp->cn_nameptr; 350 if (namelen == 1 && *pname == '.') { 351 pn = pd; 352 *vpp = vn; 353 VREF(vn); 354 PFS_RETURN (0); 355 } 356 357 /* parent */ 358 if (cnp->cn_flags & ISDOTDOT) { 359 if (pd->pn_type == pfstype_root) 360 PFS_RETURN (EIO); 361 VOP_UNLOCK(vn, 0, cnp->cn_thread); 362 cnp->cn_flags |= PDIRUNLOCK; 363 364 KASSERT(pd->pn_parent, ("non-root directory has no parent")); 365 /* 366 * This one is tricky. Descendents of procdir nodes 367 * inherit their parent's process affinity, but 368 * there's no easy reverse mapping. For simplicity, 369 * we assume that if this node is a procdir, its 370 * parent isn't (which is correct as long as 371 * descendents of procdir nodes are never procdir 372 * nodes themselves) 373 */ 374 if (pd->pn_type == pfstype_procdir) 375 pid = NO_PID; 376 pn = pd->pn_parent; 377 goto got_pnode; 378 } 379 380 /* named node */ 381 for (pn = pd->pn_nodes; pn != NULL; pn = pn->pn_next) 382 if (pn->pn_type == pfstype_procdir) 383 pdn = pn; 384 else if (pn->pn_name[namelen] == '\0' 385 && bcmp(pname, pn->pn_name, namelen) == 0) 386 goto got_pnode; 387 388 /* process dependent node */ 389 if ((pn = pdn) != NULL) { 390 pid = 0; 391 for (pid = 0, i = 0; i < namelen && isdigit(pname[i]); ++i) 392 if ((pid = pid * 10 + pname[i] - '0') > PID_MAX) 393 break; 394 if (i == cnp->cn_namelen) 395 goto got_pnode; 396 } 397 398 PFS_RETURN (ENOENT); 399 got_pnode: 400 if (pn != pd->pn_parent && !pn->pn_parent) 401 pn->pn_parent = pd; 402 if (!pfs_visible(curthread, pn, pvd->pvd_pid)) 403 PFS_RETURN (ENOENT); 404 405 error = pfs_vncache_alloc(vn->v_mount, vpp, pn, pid); 406 if (error) 407 PFS_RETURN (error); 408 409 if ((cnp->cn_flags & ISDOTDOT) && (cnp->cn_flags & ISLASTCN) 410 && lockparent) { 411 vn_lock(vn, LK_EXCLUSIVE|LK_RETRY, cnp->cn_thread); 412 cnp->cn_flags &= ~PDIRUNLOCK; 413 } 414 if (!lockparent || !(cnp->cn_flags & ISLASTCN)) 415 VOP_UNLOCK(vn, 0, cnp->cn_thread); 416 417 /* 418 * XXX See comment at top of the routine. 419 */ 420 if (cnp->cn_flags & MAKEENTRY) 421 cache_enter(vn, *vpp, cnp); 422 PFS_RETURN (0); 423 } 424 425 /* 426 * Open a file or directory. 427 */ 428 static int 429 pfs_open(struct vop_open_args *va) 430 { 431 struct vnode *vn = va->a_vp; 432 struct pfs_vdata *pvd = (struct pfs_vdata *)vn->v_data; 433 struct pfs_node *pn = pvd->pvd_pn; 434 int mode = va->a_mode; 435 436 PFS_TRACE(("%s (mode 0x%x)", pn->pn_name, mode)); 437 438 /* 439 * check if the file is visible to the caller 440 * 441 * XXX Not sure if this is necessary, as the VFS system calls 442 * XXX pfs_lookup() and pfs_access() first, and pfs_lookup() 443 * XXX calls pfs_visible(). There's a race condition here, but 444 * XXX calling pfs_visible() from here doesn't really close it, 445 * XXX and the only consequence of that race is an EIO further 446 * XXX down the line. 447 */ 448 if (!pfs_visible(va->a_td, pn, pvd->pvd_pid)) 449 PFS_RETURN (ENOENT); 450 451 /* check if the requested mode is permitted */ 452 if (((mode & FREAD) && !(mode & PFS_RD)) || 453 ((mode & FWRITE) && !(mode & PFS_WR))) 454 PFS_RETURN (EPERM); 455 456 /* we don't support locking */ 457 if ((mode & O_SHLOCK) || (mode & O_EXLOCK)) 458 PFS_RETURN (EOPNOTSUPP); 459 460 PFS_RETURN (0); 461 } 462 463 /* 464 * Read from a file 465 */ 466 static int 467 pfs_read(struct vop_read_args *va) 468 { 469 struct vnode *vn = va->a_vp; 470 struct pfs_vdata *pvd = (struct pfs_vdata *)vn->v_data; 471 struct pfs_node *pn = pvd->pvd_pn; 472 struct uio *uio = va->a_uio; 473 struct proc *proc = NULL; 474 struct sbuf *sb = NULL; 475 char *ps; 476 int error, xlen; 477 478 PFS_TRACE((pn->pn_name)); 479 480 if (vn->v_type != VREG) 481 PFS_RETURN (EINVAL); 482 483 if (!(pn->pn_flags & PFS_RD)) 484 PFS_RETURN (EBADF); 485 486 if (pn->pn_func == NULL) 487 PFS_RETURN (EIO); 488 489 /* 490 * This is necessary because either process' privileges may 491 * have changed since the open() call. 492 */ 493 if (!pfs_visible(curthread, pn, pvd->pvd_pid)) 494 PFS_RETURN (EIO); 495 496 /* XXX duplicates bits of pfs_visible() */ 497 if (pvd->pvd_pid != NO_PID) { 498 if ((proc = pfind(pvd->pvd_pid)) == NULL) 499 PFS_RETURN (EIO); 500 _PHOLD(proc); 501 PROC_UNLOCK(proc); 502 } 503 504 if (pn->pn_flags & PFS_RAWRD) { 505 error = (pn->pn_func)(curthread, proc, pn, NULL, uio); 506 if (proc != NULL) 507 PRELE(proc); 508 PFS_RETURN (error); 509 } 510 511 sb = sbuf_new(sb, NULL, uio->uio_offset + uio->uio_resid, 0); 512 if (sb == NULL) { 513 if (proc != NULL) 514 PRELE(proc); 515 PFS_RETURN (EIO); 516 } 517 518 error = (pn->pn_func)(curthread, proc, pn, sb, uio); 519 520 if (proc != NULL) 521 PRELE(proc); 522 523 if (error) { 524 sbuf_delete(sb); 525 PFS_RETURN (error); 526 } 527 528 /* XXX we should possibly detect and handle overflows */ 529 sbuf_finish(sb); 530 ps = sbuf_data(sb) + uio->uio_offset; 531 xlen = sbuf_len(sb) - uio->uio_offset; 532 xlen = imin(xlen, uio->uio_resid); 533 error = (xlen <= 0 ? 0 : uiomove(ps, xlen, uio)); 534 sbuf_delete(sb); 535 PFS_RETURN (error); 536 } 537 538 /* 539 * Iterate through directory entries 540 */ 541 static int 542 pfs_iterate(struct thread *td, pid_t pid, struct pfs_node *pd, 543 struct pfs_node **pn, struct proc **p) 544 { 545 if ((*pn) == NULL) 546 *pn = pd->pn_nodes; 547 else 548 again: 549 if ((*pn)->pn_type != pfstype_procdir) 550 *pn = (*pn)->pn_next; 551 552 while (*pn != NULL && (*pn)->pn_type == pfstype_procdir) { 553 if (*p == NULL) 554 *p = LIST_FIRST(&allproc); 555 else 556 *p = LIST_NEXT(*p, p_list); 557 if (*p != NULL) 558 break; 559 *pn = (*pn)->pn_next; 560 } 561 562 if ((*pn) == NULL) 563 return (-1); 564 565 if (!pfs_visible(td, *pn, *p ? (*p)->p_pid : pid)) 566 goto again; 567 568 return (0); 569 } 570 571 /* 572 * Return directory entries. 573 */ 574 static int 575 pfs_readdir(struct vop_readdir_args *va) 576 { 577 struct vnode *vn = va->a_vp; 578 struct pfs_info *pi = (struct pfs_info *)vn->v_mount->mnt_data; 579 struct pfs_vdata *pvd = (struct pfs_vdata *)vn->v_data; 580 struct pfs_node *pd = pvd->pvd_pn; 581 pid_t pid = pvd->pvd_pid; 582 struct pfs_node *pn; 583 struct dirent entry; 584 struct uio *uio; 585 struct proc *p; 586 off_t offset; 587 int error, i, resid; 588 589 PFS_TRACE((pd->pn_name)); 590 591 if (vn->v_type != VDIR) 592 PFS_RETURN (ENOTDIR); 593 uio = va->a_uio; 594 595 /* check if the directory is visible to the caller */ 596 if (!pfs_visible(curthread, pd, pid)) 597 PFS_RETURN (ENOENT); 598 599 /* only allow reading entire entries */ 600 offset = uio->uio_offset; 601 resid = uio->uio_resid; 602 if (offset < 0 || offset % PFS_DELEN != 0 || resid < PFS_DELEN) 603 PFS_RETURN (EINVAL); 604 605 /* skip unwanted entries */ 606 sx_slock(&allproc_lock); 607 for (pn = NULL, p = NULL; offset > 0; offset -= PFS_DELEN) 608 if (pfs_iterate(curthread, pid, pd, &pn, &p) == -1) { 609 /* nothing left... */ 610 sx_sunlock(&allproc_lock); 611 PFS_RETURN (0); 612 } 613 614 /* fill in entries */ 615 entry.d_reclen = PFS_DELEN; 616 while (pfs_iterate(curthread, pid, pd, &pn, &p) != -1 && resid > 0) { 617 if (!pn->pn_parent) 618 pn->pn_parent = pd; 619 if (!pn->pn_fileno) 620 pfs_fileno_alloc(pi, pn); 621 if (pid != NO_PID) 622 entry.d_fileno = pn->pn_fileno * NO_PID + pid; 623 else 624 entry.d_fileno = pn->pn_fileno; 625 /* PFS_DELEN was picked to fit PFS_NAMLEN */ 626 for (i = 0; i < PFS_NAMELEN - 1 && pn->pn_name[i] != '\0'; ++i) 627 entry.d_name[i] = pn->pn_name[i]; 628 entry.d_name[i] = 0; 629 entry.d_namlen = i; 630 switch (pn->pn_type) { 631 case pfstype_procdir: 632 KASSERT(p != NULL, 633 ("reached procdir node with p == NULL")); 634 entry.d_fileno = pn->pn_fileno * NO_PID + p->p_pid; 635 entry.d_namlen = snprintf(entry.d_name, 636 PFS_NAMELEN, "%d", p->p_pid); 637 /* fall through */ 638 case pfstype_root: 639 case pfstype_dir: 640 case pfstype_this: 641 case pfstype_parent: 642 entry.d_type = DT_DIR; 643 break; 644 case pfstype_file: 645 entry.d_type = DT_REG; 646 break; 647 case pfstype_symlink: 648 entry.d_type = DT_LNK; 649 break; 650 default: 651 sx_sunlock(&allproc_lock); 652 panic("%s has unexpected node type: %d", pn->pn_name, pn->pn_type); 653 } 654 PFS_TRACE((entry.d_name)); 655 if ((error = uiomove(&entry, PFS_DELEN, uio))) { 656 sx_sunlock(&allproc_lock); 657 PFS_RETURN (error); 658 } 659 offset += PFS_DELEN; 660 resid -= PFS_DELEN; 661 } 662 663 sx_sunlock(&allproc_lock); 664 uio->uio_offset += offset; 665 PFS_RETURN (0); 666 } 667 668 /* 669 * Read a symbolic link 670 */ 671 static int 672 pfs_readlink(struct vop_readlink_args *va) 673 { 674 struct vnode *vn = va->a_vp; 675 struct pfs_vdata *pvd = (struct pfs_vdata *)vn->v_data; 676 struct pfs_node *pn = pvd->pvd_pn; 677 struct uio *uio = va->a_uio; 678 struct proc *proc = NULL; 679 char buf[MAXPATHLEN], *ps; 680 struct sbuf sb; 681 int error, xlen; 682 683 PFS_TRACE((pn->pn_name)); 684 685 if (vn->v_type != VLNK) 686 PFS_RETURN (EINVAL); 687 688 if (pn->pn_func == NULL) 689 PFS_RETURN (EIO); 690 691 if (pvd->pvd_pid != NO_PID) { 692 if ((proc = pfind(pvd->pvd_pid)) == NULL) 693 PFS_RETURN (EIO); 694 _PHOLD(proc); 695 PROC_UNLOCK(proc); 696 } 697 698 /* sbuf_new() can't fail with a static buffer */ 699 sbuf_new(&sb, buf, sizeof buf, 0); 700 701 error = (pn->pn_func)(curthread, proc, pn, &sb, NULL); 702 703 if (proc != NULL) 704 PRELE(proc); 705 706 if (error) { 707 sbuf_delete(&sb); 708 PFS_RETURN (error); 709 } 710 711 /* XXX we should detect and handle overflows */ 712 sbuf_finish(&sb); 713 ps = sbuf_data(&sb) + uio->uio_offset; 714 xlen = sbuf_len(&sb) - uio->uio_offset; 715 xlen = imin(xlen, uio->uio_resid); 716 error = (xlen <= 0 ? 0 : uiomove(ps, xlen, uio)); 717 sbuf_delete(&sb); 718 PFS_RETURN (error); 719 } 720 721 /* 722 * Reclaim a vnode 723 */ 724 static int 725 pfs_reclaim(struct vop_reclaim_args *va) 726 { 727 PFS_TRACE((((struct pfs_vdata *)va->a_vp->v_data)->pvd_pn->pn_name)); 728 729 return (pfs_vncache_free(va->a_vp)); 730 } 731 732 /* 733 * Set attributes 734 */ 735 static int 736 pfs_setattr(struct vop_setattr_args *va) 737 { 738 PFS_TRACE((((struct pfs_vdata *)va->a_vp->v_data)->pvd_pn->pn_name)); 739 740 PFS_RETURN (EOPNOTSUPP); 741 } 742 743 /* 744 * Read from a file 745 */ 746 static int 747 pfs_write(struct vop_read_args *va) 748 { 749 struct vnode *vn = va->a_vp; 750 struct pfs_vdata *pvd = (struct pfs_vdata *)vn->v_data; 751 struct pfs_node *pn = pvd->pvd_pn; 752 struct uio *uio = va->a_uio; 753 struct proc *proc = NULL; 754 struct sbuf sb; 755 int error; 756 757 PFS_TRACE((pn->pn_name)); 758 759 if (vn->v_type != VREG) 760 PFS_RETURN (EINVAL); 761 762 if (!(pn->pn_flags & PFS_WR)) 763 PFS_RETURN (EBADF); 764 765 if (pn->pn_func == NULL) 766 PFS_RETURN (EIO); 767 768 /* 769 * This is necessary because either process' privileges may 770 * have changed since the open() call. 771 */ 772 if (!pfs_visible(curthread, pn, pvd->pvd_pid)) 773 PFS_RETURN (EIO); 774 775 /* XXX duplicates bits of pfs_visible() */ 776 if (pvd->pvd_pid != NO_PID) { 777 if ((proc = pfind(pvd->pvd_pid)) == NULL) 778 PFS_RETURN (EIO); 779 _PHOLD(proc); 780 PROC_UNLOCK(proc); 781 } 782 783 if (pn->pn_flags & PFS_RAWWR) { 784 error = (pn->pn_func)(curthread, proc, pn, NULL, uio); 785 if (proc != NULL) 786 PRELE(proc); 787 PFS_RETURN (error); 788 } 789 790 sbuf_uionew(&sb, uio, &error); 791 if (error) 792 PFS_RETURN (error); 793 794 error = (pn->pn_func)(curthread, proc, pn, &sb, uio); 795 796 if (proc != NULL) 797 PRELE(proc); 798 799 sbuf_delete(&sb); 800 PFS_RETURN (error); 801 } 802 803 /* 804 * Vnode operations 805 */ 806 vop_t **pfs_vnodeop_p; 807 static struct vnodeopv_entry_desc pfs_vnodeop_entries[] = { 808 { &vop_default_desc, (vop_t *)vop_defaultop }, 809 { &vop_access_desc, (vop_t *)pfs_access }, 810 { &vop_close_desc, (vop_t *)pfs_close }, 811 { &vop_create_desc, (vop_t *)vop_eopnotsupp }, 812 { &vop_getattr_desc, (vop_t *)pfs_getattr }, 813 { &vop_getextattr_desc, (vop_t *)pfs_getextattr }, 814 { &vop_ioctl_desc, (vop_t *)pfs_ioctl }, 815 { &vop_link_desc, (vop_t *)vop_eopnotsupp }, 816 { &vop_lookup_desc, (vop_t *)pfs_lookup }, 817 { &vop_mkdir_desc, (vop_t *)vop_eopnotsupp }, 818 { &vop_mknod_desc, (vop_t *)vop_eopnotsupp }, 819 { &vop_open_desc, (vop_t *)pfs_open }, 820 { &vop_read_desc, (vop_t *)pfs_read }, 821 { &vop_readdir_desc, (vop_t *)pfs_readdir }, 822 { &vop_readlink_desc, (vop_t *)pfs_readlink }, 823 { &vop_reclaim_desc, (vop_t *)pfs_reclaim }, 824 { &vop_remove_desc, (vop_t *)vop_eopnotsupp }, 825 { &vop_rename_desc, (vop_t *)vop_eopnotsupp }, 826 { &vop_rmdir_desc, (vop_t *)vop_eopnotsupp }, 827 { &vop_setattr_desc, (vop_t *)pfs_setattr }, 828 { &vop_symlink_desc, (vop_t *)vop_eopnotsupp }, 829 { &vop_write_desc, (vop_t *)pfs_write }, 830 /* XXX I've probably forgotten a few that need vop_eopnotsupp */ 831 { NULL, (vop_t *)NULL } 832 }; 833 834 static struct vnodeopv_desc pfs_vnodeop_opv_desc = 835 { &pfs_vnodeop_p, pfs_vnodeop_entries }; 836 837 VNODEOP_SET(pfs_vnodeop_opv_desc); 838