vfs_vnops.c revision 1.94
1 /* $NetBSD: vfs_vnops.c,v 1.94 2005/07/23 18:19:51 erh Exp $ */ 2 3 /* 4 * Copyright (c) 1982, 1986, 1989, 1993 5 * The Regents of the University of California. All rights reserved. 6 * (c) UNIX System Laboratories, Inc. 7 * All or some portions of this file are derived from material licensed 8 * to the University of California by American Telephone and Telegraph 9 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 10 * the permission of UNIX System Laboratories, Inc. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 3. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 * 36 * @(#)vfs_vnops.c 8.14 (Berkeley) 6/15/95 37 */ 38 39 #include <sys/cdefs.h> 40 __KERNEL_RCSID(0, "$NetBSD: vfs_vnops.c,v 1.94 2005/07/23 18:19:51 erh Exp $"); 41 42 #include "opt_verified_exec.h" 43 44 #include "fs_union.h" 45 46 #include <sys/param.h> 47 #include <sys/systm.h> 48 #include <sys/kernel.h> 49 #include <sys/file.h> 50 #include <sys/stat.h> 51 #include <sys/buf.h> 52 #include <sys/proc.h> 53 #include <sys/malloc.h> 54 #include <sys/mount.h> 55 #include <sys/namei.h> 56 #include <sys/vnode.h> 57 #include <sys/ioctl.h> 58 #include <sys/tty.h> 59 #include <sys/poll.h> 60 61 #include <miscfs/specfs/specdev.h> 62 63 #include <uvm/uvm_extern.h> 64 65 #ifdef UNION 66 #include <fs/union/union.h> 67 #endif 68 69 #if defined(LKM) || defined(UNION) 70 int (*vn_union_readdir_hook) (struct vnode **, struct file *, struct proc *); 71 #endif 72 73 #ifdef VERIFIED_EXEC 74 #include <sys/verified_exec.h> 75 #endif 76 77 static int vn_read(struct file *fp, off_t *offset, struct uio *uio, 78 struct ucred *cred, int flags); 79 static int vn_write(struct file *fp, off_t *offset, struct uio *uio, 80 struct ucred *cred, int flags); 81 static int vn_closefile(struct file *fp, struct proc *p); 82 static int vn_poll(struct file *fp, int events, struct proc *p); 83 static int vn_fcntl(struct file *fp, u_int com, void *data, struct proc *p); 84 static int vn_statfile(struct file *fp, struct stat *sb, struct proc *p); 85 static int vn_ioctl(struct file *fp, u_long com, void *data, struct proc *p); 86 87 const struct fileops vnops = { 88 vn_read, vn_write, vn_ioctl, vn_fcntl, vn_poll, 89 vn_statfile, vn_closefile, vn_kqfilter 90 }; 91 92 /* 93 * Common code for vnode open operations. 94 * Check permissions, and call the VOP_OPEN or VOP_CREATE routine. 95 */ 96 int 97 vn_open(struct nameidata *ndp, int fmode, int cmode) 98 { 99 struct vnode *vp; 100 struct mount *mp; 101 struct proc *p = ndp->ni_cnd.cn_proc; 102 struct ucred *cred = p->p_ucred; 103 struct vattr va; 104 int error; 105 #ifdef VERIFIED_EXEC 106 struct veriexec_hash_entry *vhe = NULL; 107 #endif /* VERIFIED_EXEC */ 108 109 restart: 110 if (fmode & O_CREAT) { 111 ndp->ni_cnd.cn_nameiop = CREATE; 112 ndp->ni_cnd.cn_flags = LOCKPARENT | LOCKLEAF; 113 if ((fmode & O_EXCL) == 0 && 114 ((fmode & O_NOFOLLOW) == 0)) 115 ndp->ni_cnd.cn_flags |= FOLLOW; 116 if ((error = namei(ndp)) != 0) 117 return (error); 118 if (ndp->ni_vp == NULL) { 119 #ifdef VERIFIED_EXEC 120 /* Lockdown mode: Prevent creation of new files. */ 121 if (veriexec_strict >= 3) { 122 VOP_ABORTOP(ndp->ni_dvp, &ndp->ni_cnd); 123 124 printf("Veriexec: vn_open: Preventing " 125 "new file creation in %s.\n", 126 ndp->ni_dirp); 127 128 vp = ndp->ni_dvp; 129 error = EPERM; 130 goto bad; 131 } 132 #endif /* VERIFIED_EXEC */ 133 134 VATTR_NULL(&va); 135 va.va_type = VREG; 136 va.va_mode = cmode; 137 if (fmode & O_EXCL) 138 va.va_vaflags |= VA_EXCLUSIVE; 139 if (vn_start_write(ndp->ni_dvp, &mp, V_NOWAIT) != 0) { 140 VOP_ABORTOP(ndp->ni_dvp, &ndp->ni_cnd); 141 vput(ndp->ni_dvp); 142 if ((error = vn_start_write(NULL, &mp, 143 V_WAIT | V_SLEEPONLY | V_PCATCH)) != 0) 144 return (error); 145 goto restart; 146 } 147 VOP_LEASE(ndp->ni_dvp, p, cred, LEASE_WRITE); 148 error = VOP_CREATE(ndp->ni_dvp, &ndp->ni_vp, 149 &ndp->ni_cnd, &va); 150 vn_finished_write(mp, 0); 151 if (error) 152 return (error); 153 fmode &= ~O_TRUNC; 154 vp = ndp->ni_vp; 155 } else { 156 VOP_ABORTOP(ndp->ni_dvp, &ndp->ni_cnd); 157 if (ndp->ni_dvp == ndp->ni_vp) 158 vrele(ndp->ni_dvp); 159 else 160 vput(ndp->ni_dvp); 161 ndp->ni_dvp = NULL; 162 vp = ndp->ni_vp; 163 if (fmode & O_EXCL) { 164 error = EEXIST; 165 goto bad; 166 } 167 fmode &= ~O_CREAT; 168 } 169 } else { 170 ndp->ni_cnd.cn_nameiop = LOOKUP; 171 ndp->ni_cnd.cn_flags = LOCKLEAF; 172 if ((fmode & O_NOFOLLOW) == 0) 173 ndp->ni_cnd.cn_flags |= FOLLOW; 174 if ((error = namei(ndp)) != 0) 175 return (error); 176 vp = ndp->ni_vp; 177 } 178 if (vp->v_type == VSOCK) { 179 error = EOPNOTSUPP; 180 goto bad; 181 } 182 if (ndp->ni_vp->v_type == VLNK) { 183 error = EFTYPE; 184 goto bad; 185 } 186 187 #ifdef VERIFIED_EXEC 188 if ((error = VOP_GETATTR(vp, &va, cred, p)) != 0) 189 goto bad; 190 #endif 191 192 if ((fmode & O_CREAT) == 0) { 193 #ifdef VERIFIED_EXEC 194 /* XXX may need pathbuf instead */ 195 if ((error = veriexec_verify(p, vp, &va, ndp->ni_dirp, 196 VERIEXEC_FILE, &vhe)) != 0) 197 goto bad; 198 #endif 199 200 if (fmode & FREAD) { 201 if ((error = VOP_ACCESS(vp, VREAD, cred, p)) != 0) 202 goto bad; 203 } 204 205 if (fmode & (FWRITE | O_TRUNC)) { 206 if (vp->v_type == VDIR) { 207 error = EISDIR; 208 goto bad; 209 } 210 if ((error = vn_writechk(vp)) != 0 || 211 (error = VOP_ACCESS(vp, VWRITE, cred, p)) != 0) 212 goto bad; 213 #ifdef VERIFIED_EXEC 214 if (vhe != NULL) { 215 veriexec_report("Write access request.", 216 ndp->ni_dirp, &va, p, 217 REPORT_NOVERBOSE, 218 REPORT_ALARM, 219 REPORT_NOPANIC); 220 221 /* IPS mode: Deny writing to monitored files. */ 222 if (veriexec_strict >= 2) { 223 error = EPERM; 224 goto bad; 225 } else { 226 vhe->status = FINGERPRINT_NOTEVAL; 227 } 228 } 229 #endif 230 } 231 } 232 233 if (fmode & O_TRUNC) { 234 VOP_UNLOCK(vp, 0); /* XXX */ 235 if ((error = vn_start_write(vp, &mp, V_WAIT | V_PCATCH)) != 0) { 236 vput(vp); 237 return (error); 238 } 239 VOP_LEASE(vp, p, cred, LEASE_WRITE); 240 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); /* XXX */ 241 VATTR_NULL(&va); 242 va.va_size = 0; 243 error = VOP_SETATTR(vp, &va, cred, p); 244 vn_finished_write(mp, 0); 245 if (error != 0) 246 goto bad; 247 } 248 if ((error = VOP_OPEN(vp, fmode, cred, p)) != 0) 249 goto bad; 250 if (vp->v_type == VREG && 251 uvn_attach(vp, fmode & FWRITE ? VM_PROT_WRITE : 0) == NULL) { 252 error = EIO; 253 goto bad; 254 } 255 if (fmode & FWRITE) 256 vp->v_writecount++; 257 258 return (0); 259 bad: 260 vput(vp); 261 return (error); 262 } 263 264 /* 265 * Check for write permissions on the specified vnode. 266 * Prototype text segments cannot be written. 267 */ 268 int 269 vn_writechk(struct vnode *vp) 270 { 271 272 /* 273 * If the vnode is in use as a process's text, 274 * we can't allow writing. 275 */ 276 if (vp->v_flag & VTEXT) 277 return (ETXTBSY); 278 return (0); 279 } 280 281 /* 282 * Mark a vnode as having executable mappings. 283 */ 284 void 285 vn_markexec(struct vnode *vp) 286 { 287 if ((vp->v_flag & VEXECMAP) == 0) { 288 uvmexp.filepages -= vp->v_uobj.uo_npages; 289 uvmexp.execpages += vp->v_uobj.uo_npages; 290 } 291 vp->v_flag |= VEXECMAP; 292 } 293 294 /* 295 * Mark a vnode as being the text of a process. 296 * Fail if the vnode is currently writable. 297 */ 298 int 299 vn_marktext(struct vnode *vp) 300 { 301 302 if (vp->v_writecount != 0) { 303 KASSERT((vp->v_flag & VTEXT) == 0); 304 return (ETXTBSY); 305 } 306 vp->v_flag |= VTEXT; 307 vn_markexec(vp); 308 return (0); 309 } 310 311 /* 312 * Vnode close call 313 * 314 * Note: takes an unlocked vnode, while VOP_CLOSE takes a locked node. 315 */ 316 int 317 vn_close(struct vnode *vp, int flags, struct ucred *cred, struct proc *p) 318 { 319 int error; 320 321 if (flags & FWRITE) 322 vp->v_writecount--; 323 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 324 error = VOP_CLOSE(vp, flags, cred, p); 325 vput(vp); 326 return (error); 327 } 328 329 /* 330 * Package up an I/O request on a vnode into a uio and do it. 331 */ 332 int 333 vn_rdwr(enum uio_rw rw, struct vnode *vp, caddr_t base, int len, off_t offset, 334 enum uio_seg segflg, int ioflg, struct ucred *cred, size_t *aresid, 335 struct proc *p) 336 { 337 struct uio auio; 338 struct iovec aiov; 339 struct mount *mp; 340 int error; 341 342 if ((ioflg & IO_NODELOCKED) == 0) { 343 if (rw == UIO_READ) { 344 vn_lock(vp, LK_SHARED | LK_RETRY); 345 } else /* UIO_WRITE */ { 346 if (vp->v_type != VCHR && 347 (error = vn_start_write(vp, &mp, V_WAIT | V_PCATCH)) 348 != 0) 349 return (error); 350 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 351 } 352 } 353 auio.uio_iov = &aiov; 354 auio.uio_iovcnt = 1; 355 aiov.iov_base = base; 356 aiov.iov_len = len; 357 auio.uio_resid = len; 358 auio.uio_offset = offset; 359 auio.uio_segflg = segflg; 360 auio.uio_rw = rw; 361 auio.uio_procp = p; 362 if (rw == UIO_READ) { 363 error = VOP_READ(vp, &auio, ioflg, cred); 364 } else { 365 error = VOP_WRITE(vp, &auio, ioflg, cred); 366 } 367 if (aresid) 368 *aresid = auio.uio_resid; 369 else 370 if (auio.uio_resid && error == 0) 371 error = EIO; 372 if ((ioflg & IO_NODELOCKED) == 0) { 373 if (rw == UIO_WRITE) 374 vn_finished_write(mp, 0); 375 VOP_UNLOCK(vp, 0); 376 } 377 return (error); 378 } 379 380 int 381 vn_readdir(struct file *fp, char *bf, int segflg, u_int count, int *done, 382 struct proc *p, off_t **cookies, int *ncookies) 383 { 384 struct vnode *vp = (struct vnode *)fp->f_data; 385 struct iovec aiov; 386 struct uio auio; 387 int error, eofflag; 388 389 unionread: 390 if (vp->v_type != VDIR) 391 return (EINVAL); 392 aiov.iov_base = bf; 393 aiov.iov_len = count; 394 auio.uio_iov = &aiov; 395 auio.uio_iovcnt = 1; 396 auio.uio_rw = UIO_READ; 397 auio.uio_segflg = segflg; 398 auio.uio_procp = p; 399 auio.uio_resid = count; 400 vn_lock(vp, LK_SHARED | LK_RETRY); 401 auio.uio_offset = fp->f_offset; 402 error = VOP_READDIR(vp, &auio, fp->f_cred, &eofflag, cookies, 403 ncookies); 404 fp->f_offset = auio.uio_offset; 405 VOP_UNLOCK(vp, 0); 406 if (error) 407 return (error); 408 409 #if defined(UNION) || defined(LKM) 410 if (count == auio.uio_resid && vn_union_readdir_hook) { 411 struct vnode *ovp = vp; 412 413 error = (*vn_union_readdir_hook)(&vp, fp, p); 414 if (error) 415 return (error); 416 if (vp != ovp) 417 goto unionread; 418 } 419 #endif /* UNION || LKM */ 420 421 if (count == auio.uio_resid && (vp->v_flag & VROOT) && 422 (vp->v_mount->mnt_flag & MNT_UNION)) { 423 struct vnode *tvp = vp; 424 vp = vp->v_mount->mnt_vnodecovered; 425 VREF(vp); 426 fp->f_data = vp; 427 fp->f_offset = 0; 428 vrele(tvp); 429 goto unionread; 430 } 431 *done = count - auio.uio_resid; 432 return error; 433 } 434 435 /* 436 * File table vnode read routine. 437 */ 438 static int 439 vn_read(struct file *fp, off_t *offset, struct uio *uio, struct ucred *cred, 440 int flags) 441 { 442 struct vnode *vp = (struct vnode *)fp->f_data; 443 int count, error, ioflag = 0; 444 445 VOP_LEASE(vp, uio->uio_procp, cred, LEASE_READ); 446 if (fp->f_flag & FNONBLOCK) 447 ioflag |= IO_NDELAY; 448 if ((fp->f_flag & (FFSYNC | FRSYNC)) == (FFSYNC | FRSYNC)) 449 ioflag |= IO_SYNC; 450 if (fp->f_flag & FALTIO) 451 ioflag |= IO_ALTSEMANTICS; 452 vn_lock(vp, LK_SHARED | LK_RETRY); 453 uio->uio_offset = *offset; 454 count = uio->uio_resid; 455 error = VOP_READ(vp, uio, ioflag, cred); 456 if (flags & FOF_UPDATE_OFFSET) 457 *offset += count - uio->uio_resid; 458 VOP_UNLOCK(vp, 0); 459 return (error); 460 } 461 462 /* 463 * File table vnode write routine. 464 */ 465 static int 466 vn_write(struct file *fp, off_t *offset, struct uio *uio, struct ucred *cred, 467 int flags) 468 { 469 struct vnode *vp = (struct vnode *)fp->f_data; 470 struct mount *mp; 471 int count, error, ioflag = IO_UNIT; 472 473 if (vp->v_type == VREG && (fp->f_flag & O_APPEND)) 474 ioflag |= IO_APPEND; 475 if (fp->f_flag & FNONBLOCK) 476 ioflag |= IO_NDELAY; 477 if (fp->f_flag & FFSYNC || 478 (vp->v_mount && (vp->v_mount->mnt_flag & MNT_SYNCHRONOUS))) 479 ioflag |= IO_SYNC; 480 else if (fp->f_flag & FDSYNC) 481 ioflag |= IO_DSYNC; 482 if (fp->f_flag & FALTIO) 483 ioflag |= IO_ALTSEMANTICS; 484 mp = NULL; 485 if (vp->v_type != VCHR && 486 (error = vn_start_write(vp, &mp, V_WAIT | V_PCATCH)) != 0) 487 return (error); 488 VOP_LEASE(vp, uio->uio_procp, cred, LEASE_WRITE); 489 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 490 uio->uio_offset = *offset; 491 count = uio->uio_resid; 492 error = VOP_WRITE(vp, uio, ioflag, cred); 493 if (flags & FOF_UPDATE_OFFSET) { 494 if (ioflag & IO_APPEND) 495 *offset = uio->uio_offset; 496 else 497 *offset += count - uio->uio_resid; 498 } 499 VOP_UNLOCK(vp, 0); 500 vn_finished_write(mp, 0); 501 return (error); 502 } 503 504 /* 505 * File table vnode stat routine. 506 */ 507 static int 508 vn_statfile(struct file *fp, struct stat *sb, struct proc *p) 509 { 510 struct vnode *vp = (struct vnode *)fp->f_data; 511 512 return vn_stat(vp, sb, p); 513 } 514 515 int 516 vn_stat(struct vnode *vp, struct stat *sb, struct proc *p) 517 { 518 struct vattr va; 519 int error; 520 mode_t mode; 521 522 error = VOP_GETATTR(vp, &va, p->p_ucred, p); 523 if (error) 524 return (error); 525 /* 526 * Copy from vattr table 527 */ 528 sb->st_dev = va.va_fsid; 529 sb->st_ino = va.va_fileid; 530 mode = va.va_mode; 531 switch (vp->v_type) { 532 case VREG: 533 mode |= S_IFREG; 534 break; 535 case VDIR: 536 mode |= S_IFDIR; 537 break; 538 case VBLK: 539 mode |= S_IFBLK; 540 break; 541 case VCHR: 542 mode |= S_IFCHR; 543 break; 544 case VLNK: 545 mode |= S_IFLNK; 546 break; 547 case VSOCK: 548 mode |= S_IFSOCK; 549 break; 550 case VFIFO: 551 mode |= S_IFIFO; 552 break; 553 default: 554 return (EBADF); 555 }; 556 sb->st_mode = mode; 557 sb->st_nlink = va.va_nlink; 558 sb->st_uid = va.va_uid; 559 sb->st_gid = va.va_gid; 560 sb->st_rdev = va.va_rdev; 561 sb->st_size = va.va_size; 562 sb->st_atimespec = va.va_atime; 563 sb->st_mtimespec = va.va_mtime; 564 sb->st_ctimespec = va.va_ctime; 565 sb->st_birthtimespec = va.va_birthtime; 566 sb->st_blksize = va.va_blocksize; 567 sb->st_flags = va.va_flags; 568 sb->st_gen = 0; 569 sb->st_blocks = va.va_bytes / S_BLKSIZE; 570 return (0); 571 } 572 573 /* 574 * File table vnode fcntl routine. 575 */ 576 static int 577 vn_fcntl(struct file *fp, u_int com, void *data, struct proc *p) 578 { 579 struct vnode *vp = ((struct vnode *)fp->f_data); 580 int error; 581 582 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 583 error = VOP_FCNTL(vp, com, data, fp->f_flag, p->p_ucred, p); 584 VOP_UNLOCK(vp, 0); 585 return (error); 586 } 587 588 /* 589 * File table vnode ioctl routine. 590 */ 591 static int 592 vn_ioctl(struct file *fp, u_long com, void *data, struct proc *p) 593 { 594 struct vnode *vp = ((struct vnode *)fp->f_data); 595 struct vattr vattr; 596 int error; 597 598 switch (vp->v_type) { 599 600 case VREG: 601 case VDIR: 602 if (com == FIONREAD) { 603 error = VOP_GETATTR(vp, &vattr, p->p_ucred, p); 604 if (error) 605 return (error); 606 *(int *)data = vattr.va_size - fp->f_offset; 607 return (0); 608 } 609 if ((com == FIONWRITE) || (com == FIONSPACE)) { 610 /* 611 * Files don't have send queues, so there never 612 * are any bytes in them, nor is there any 613 * open space in them. 614 */ 615 *(int *)data = 0; 616 return (0); 617 } 618 if (com == FIOGETBMAP) { 619 daddr_t *block; 620 621 if (*(daddr_t *)data < 0) 622 return (EINVAL); 623 block = (daddr_t *)data; 624 return (VOP_BMAP(vp, *block, NULL, block, NULL)); 625 } 626 if (com == OFIOGETBMAP) { 627 daddr_t ibn, obn; 628 629 if (*(int32_t *)data < 0) 630 return (EINVAL); 631 ibn = (daddr_t)*(int32_t *)data; 632 error = VOP_BMAP(vp, ibn, NULL, &obn, NULL); 633 *(int32_t *)data = (int32_t)obn; 634 return error; 635 } 636 if (com == FIONBIO || com == FIOASYNC) /* XXX */ 637 return (0); /* XXX */ 638 /* fall into ... */ 639 case VFIFO: 640 case VCHR: 641 case VBLK: 642 error = VOP_IOCTL(vp, com, data, fp->f_flag, p->p_ucred, p); 643 if (error == 0 && com == TIOCSCTTY) { 644 if (p->p_session->s_ttyvp) 645 vrele(p->p_session->s_ttyvp); 646 p->p_session->s_ttyvp = vp; 647 VREF(vp); 648 } 649 return (error); 650 651 default: 652 return (EPASSTHROUGH); 653 } 654 } 655 656 /* 657 * File table vnode poll routine. 658 */ 659 static int 660 vn_poll(struct file *fp, int events, struct proc *p) 661 { 662 663 return (VOP_POLL(((struct vnode *)fp->f_data), events, p)); 664 } 665 666 /* 667 * File table vnode kqfilter routine. 668 */ 669 int 670 vn_kqfilter(struct file *fp, struct knote *kn) 671 { 672 673 return (VOP_KQFILTER((struct vnode *)fp->f_data, kn)); 674 } 675 676 /* 677 * Check that the vnode is still valid, and if so 678 * acquire requested lock. 679 */ 680 int 681 vn_lock(struct vnode *vp, int flags) 682 { 683 int error; 684 685 #if 0 686 KASSERT(vp->v_usecount > 0 || (flags & LK_INTERLOCK) != 0 687 || (vp->v_flag & VONWORKLST) != 0); 688 #endif 689 690 do { 691 if ((flags & LK_INTERLOCK) == 0) 692 simple_lock(&vp->v_interlock); 693 if (vp->v_flag & VXLOCK) { 694 if (flags & LK_NOWAIT) { 695 simple_unlock(&vp->v_interlock); 696 return EBUSY; 697 } 698 vp->v_flag |= VXWANT; 699 ltsleep(vp, PINOD | PNORELOCK, 700 "vn_lock", 0, &vp->v_interlock); 701 error = ENOENT; 702 } else { 703 error = VOP_LOCK(vp, 704 (flags & ~LK_RETRY) | LK_INTERLOCK); 705 if (error == 0 || error == EDEADLK || error == EBUSY) 706 return (error); 707 } 708 flags &= ~LK_INTERLOCK; 709 } while (flags & LK_RETRY); 710 return (error); 711 } 712 713 /* 714 * File table vnode close routine. 715 */ 716 static int 717 vn_closefile(struct file *fp, struct proc *p) 718 { 719 720 return (vn_close(((struct vnode *)fp->f_data), fp->f_flag, 721 fp->f_cred, p)); 722 } 723 724 /* 725 * Enable LK_CANRECURSE on lock. Return prior status. 726 */ 727 u_int 728 vn_setrecurse(struct vnode *vp) 729 { 730 struct lock *lkp = &vp->v_lock; 731 u_int retval = lkp->lk_flags & LK_CANRECURSE; 732 733 lkp->lk_flags |= LK_CANRECURSE; 734 return retval; 735 } 736 737 /* 738 * Called when done with locksetrecurse. 739 */ 740 void 741 vn_restorerecurse(struct vnode *vp, u_int flags) 742 { 743 struct lock *lkp = &vp->v_lock; 744 745 lkp->lk_flags &= ~LK_CANRECURSE; 746 lkp->lk_flags |= flags; 747 } 748 749 int 750 vn_cow_establish(struct vnode *vp, 751 int (*func)(void *, struct buf *), void *cookie) 752 { 753 int s; 754 struct spec_cow_entry *e; 755 756 MALLOC(e, struct spec_cow_entry *, sizeof(struct spec_cow_entry), 757 M_DEVBUF, M_WAITOK); 758 e->ce_func = func; 759 e->ce_cookie = cookie; 760 761 SPEC_COW_LOCK(vp->v_specinfo, s); 762 vp->v_spec_cow_req++; 763 while (vp->v_spec_cow_count > 0) 764 ltsleep(&vp->v_spec_cow_req, PRIBIO, "cowlist", 0, 765 &vp->v_spec_cow_slock); 766 767 SLIST_INSERT_HEAD(&vp->v_spec_cow_head, e, ce_list); 768 769 vp->v_spec_cow_req--; 770 if (vp->v_spec_cow_req == 0) 771 wakeup(&vp->v_spec_cow_req); 772 SPEC_COW_UNLOCK(vp->v_specinfo, s); 773 774 return 0; 775 } 776 777 int 778 vn_cow_disestablish(struct vnode *vp, 779 int (*func)(void *, struct buf *), void *cookie) 780 { 781 int s; 782 struct spec_cow_entry *e; 783 784 SPEC_COW_LOCK(vp->v_specinfo, s); 785 vp->v_spec_cow_req++; 786 while (vp->v_spec_cow_count > 0) 787 ltsleep(&vp->v_spec_cow_req, PRIBIO, "cowlist", 0, 788 &vp->v_spec_cow_slock); 789 790 SLIST_FOREACH(e, &vp->v_spec_cow_head, ce_list) 791 if (e->ce_func == func && e->ce_cookie == cookie) { 792 SLIST_REMOVE(&vp->v_spec_cow_head, e, 793 spec_cow_entry, ce_list); 794 FREE(e, M_DEVBUF); 795 break; 796 } 797 798 vp->v_spec_cow_req--; 799 if (vp->v_spec_cow_req == 0) 800 wakeup(&vp->v_spec_cow_req); 801 SPEC_COW_UNLOCK(vp->v_specinfo, s); 802 803 return e ? 0 : EINVAL; 804 } 805 806 /* 807 * Simplified in-kernel wrapper calls for extended attribute access. 808 * Both calls pass in a NULL credential, authorizing a "kernel" access. 809 * Set IO_NODELOCKED in ioflg if the vnode is already locked. 810 */ 811 int 812 vn_extattr_get(struct vnode *vp, int ioflg, int attrnamespace, 813 const char *attrname, size_t *buflen, void *bf, struct proc *p) 814 { 815 struct uio auio; 816 struct iovec aiov; 817 int error; 818 819 aiov.iov_len = *buflen; 820 aiov.iov_base = bf; 821 822 auio.uio_iov = &aiov; 823 auio.uio_iovcnt = 1; 824 auio.uio_rw = UIO_READ; 825 auio.uio_segflg = UIO_SYSSPACE; 826 auio.uio_procp = p; 827 auio.uio_offset = 0; 828 auio.uio_resid = *buflen; 829 830 if ((ioflg & IO_NODELOCKED) == 0) 831 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 832 833 error = VOP_GETEXTATTR(vp, attrnamespace, attrname, &auio, NULL, NULL, 834 p); 835 836 if ((ioflg & IO_NODELOCKED) == 0) 837 VOP_UNLOCK(vp, 0); 838 839 if (error == 0) 840 *buflen = *buflen - auio.uio_resid; 841 842 return (error); 843 } 844 845 /* 846 * XXX Failure mode if partially written? 847 */ 848 int 849 vn_extattr_set(struct vnode *vp, int ioflg, int attrnamespace, 850 const char *attrname, size_t buflen, const void *bf, struct proc *p) 851 { 852 struct uio auio; 853 struct iovec aiov; 854 struct mount *mp; 855 int error; 856 857 aiov.iov_len = buflen; 858 aiov.iov_base = __UNCONST(bf); /* XXXUNCONST kills const */ 859 860 auio.uio_iov = &aiov; 861 auio.uio_iovcnt = 1; 862 auio.uio_rw = UIO_WRITE; 863 auio.uio_segflg = UIO_SYSSPACE; 864 auio.uio_procp = p; 865 auio.uio_offset = 0; 866 auio.uio_resid = buflen; 867 868 if ((ioflg & IO_NODELOCKED) == 0) { 869 if ((error = vn_start_write(vp, &mp, V_WAIT)) != 0) 870 return (error); 871 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 872 } 873 874 error = VOP_SETEXTATTR(vp, attrnamespace, attrname, &auio, NULL, p); 875 876 if ((ioflg & IO_NODELOCKED) == 0) { 877 vn_finished_write(mp, 0); 878 VOP_UNLOCK(vp, 0); 879 } 880 881 return (error); 882 } 883 884 int 885 vn_extattr_rm(struct vnode *vp, int ioflg, int attrnamespace, 886 const char *attrname, struct proc *p) 887 { 888 struct mount *mp; 889 int error; 890 891 if ((ioflg & IO_NODELOCKED) == 0) { 892 if ((error = vn_start_write(vp, &mp, V_WAIT)) != 0) 893 return (error); 894 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 895 } 896 897 error = VOP_DELETEEXTATTR(vp, attrnamespace, attrname, NULL, p); 898 if (error == EOPNOTSUPP) 899 error = VOP_SETEXTATTR(vp, attrnamespace, attrname, NULL, 900 NULL, p); 901 902 if ((ioflg & IO_NODELOCKED) == 0) { 903 vn_finished_write(mp, 0); 904 VOP_UNLOCK(vp, 0); 905 } 906 907 return (error); 908 } 909
Indexes created Sat Sep 20 22:09:52 GMT 2025