vfs_vnops.c revision 1.141
1 /* $NetBSD: vfs_vnops.c,v 1.141 2007/10/07 13:39:04 hannken 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 1.141 2007/10/07 13:39:04 hannken Exp $"); 41 42 #include "fs_union.h" 43 #include "veriexec.h" 44 45 #include <sys/param.h> 46 #include <sys/systm.h> 47 #include <sys/kernel.h> 48 #include <sys/file.h> 49 #include <sys/stat.h> 50 #include <sys/buf.h> 51 #include <sys/proc.h> 52 #include <sys/malloc.h> 53 #include <sys/mount.h> 54 #include <sys/namei.h> 55 #include <sys/vnode.h> 56 #include <sys/ioctl.h> 57 #include <sys/tty.h> 58 #include <sys/poll.h> 59 #include <sys/kauth.h> 60 #include <sys/syslog.h> 61 #include <sys/fstrans.h> 62 63 #include <miscfs/specfs/specdev.h> 64 65 #include <uvm/uvm_extern.h> 66 #include <uvm/uvm_readahead.h> 67 68 #ifdef UNION 69 #include <fs/union/union.h> 70 #endif 71 72 #if defined(LKM) || defined(UNION) 73 int (*vn_union_readdir_hook) (struct vnode **, struct file *, struct lwp *); 74 #endif 75 76 #include <sys/verified_exec.h> 77 78 static int vn_read(struct file *fp, off_t *offset, struct uio *uio, 79 kauth_cred_t cred, int flags); 80 static int vn_write(struct file *fp, off_t *offset, struct uio *uio, 81 kauth_cred_t cred, int flags); 82 static int vn_closefile(struct file *fp, struct lwp *l); 83 static int vn_poll(struct file *fp, int events, struct lwp *l); 84 static int vn_fcntl(struct file *fp, u_int com, void *data, struct lwp *l); 85 static int vn_statfile(struct file *fp, struct stat *sb, struct lwp *l); 86 static int vn_ioctl(struct file *fp, u_long com, void *data, struct lwp *l); 87 88 const struct fileops vnops = { 89 vn_read, vn_write, vn_ioctl, vn_fcntl, vn_poll, 90 vn_statfile, vn_closefile, vn_kqfilter 91 }; 92 93 /* 94 * Common code for vnode open operations. 95 * Check permissions, and call the VOP_OPEN or VOP_CREATE routine. 96 */ 97 int 98 vn_open(struct nameidata *ndp, int fmode, int cmode) 99 { 100 struct vnode *vp; 101 struct lwp *l = ndp->ni_cnd.cn_lwp; 102 kauth_cred_t cred = l->l_cred; 103 struct vattr va; 104 int error; 105 char *path; 106 107 ndp->ni_cnd.cn_flags &= TRYEMULROOT; 108 109 if (fmode & O_CREAT) { 110 ndp->ni_cnd.cn_nameiop = CREATE; 111 ndp->ni_cnd.cn_flags |= LOCKPARENT | LOCKLEAF; 112 if ((fmode & O_EXCL) == 0 && 113 ((fmode & O_NOFOLLOW) == 0)) 114 ndp->ni_cnd.cn_flags |= FOLLOW; 115 } else { 116 ndp->ni_cnd.cn_nameiop = LOOKUP; 117 ndp->ni_cnd.cn_flags |= LOCKLEAF; 118 if ((fmode & O_NOFOLLOW) == 0) 119 ndp->ni_cnd.cn_flags |= FOLLOW; 120 } 121 122 VERIEXEC_PATH_GET(ndp->ni_dirp, ndp->ni_segflg, ndp->ni_dirp, path); 123 124 error = namei(ndp); 125 if (error) 126 goto out; 127 128 vp = ndp->ni_vp; 129 130 #if NVERIEXEC > 0 131 error = veriexec_openchk(l, ndp->ni_vp, ndp->ni_dirp, fmode); 132 if (error) 133 goto bad; 134 #endif /* NVERIEXEC > 0 */ 135 136 if (fmode & O_CREAT) { 137 if (ndp->ni_vp == NULL) { 138 VATTR_NULL(&va); 139 va.va_type = VREG; 140 va.va_mode = cmode; 141 if (fmode & O_EXCL) 142 va.va_vaflags |= VA_EXCLUSIVE; 143 VOP_LEASE(ndp->ni_dvp, l, cred, LEASE_WRITE); 144 error = VOP_CREATE(ndp->ni_dvp, &ndp->ni_vp, 145 &ndp->ni_cnd, &va); 146 if (error) 147 goto out; 148 fmode &= ~O_TRUNC; 149 vp = ndp->ni_vp; 150 } else { 151 VOP_ABORTOP(ndp->ni_dvp, &ndp->ni_cnd); 152 if (ndp->ni_dvp == ndp->ni_vp) 153 vrele(ndp->ni_dvp); 154 else 155 vput(ndp->ni_dvp); 156 ndp->ni_dvp = NULL; 157 vp = ndp->ni_vp; 158 if (fmode & O_EXCL) { 159 error = EEXIST; 160 goto bad; 161 } 162 fmode &= ~O_CREAT; 163 } 164 } else { 165 vp = ndp->ni_vp; 166 } 167 if (vp->v_type == VSOCK) { 168 error = EOPNOTSUPP; 169 goto bad; 170 } 171 if (ndp->ni_vp->v_type == VLNK) { 172 error = EFTYPE; 173 goto bad; 174 } 175 176 if ((fmode & O_CREAT) == 0) { 177 if (fmode & FREAD) { 178 if ((error = VOP_ACCESS(vp, VREAD, cred, l)) != 0) 179 goto bad; 180 } 181 182 if (fmode & (FWRITE | O_TRUNC)) { 183 if (vp->v_type == VDIR) { 184 error = EISDIR; 185 goto bad; 186 } 187 if ((error = vn_writechk(vp)) != 0 || 188 (error = VOP_ACCESS(vp, VWRITE, cred, l)) != 0) 189 goto bad; 190 } 191 } 192 193 if (fmode & O_TRUNC) { 194 VOP_UNLOCK(vp, 0); /* XXX */ 195 196 VOP_LEASE(vp, l, cred, LEASE_WRITE); 197 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); /* XXX */ 198 VATTR_NULL(&va); 199 va.va_size = 0; 200 error = VOP_SETATTR(vp, &va, cred, l); 201 if (error != 0) 202 goto bad; 203 } 204 if ((error = VOP_OPEN(vp, fmode, cred, l)) != 0) 205 goto bad; 206 if (fmode & FWRITE) 207 vp->v_writecount++; 208 209 bad: 210 if (error) 211 vput(vp); 212 out: 213 VERIEXEC_PATH_PUT(path); 214 return (error); 215 } 216 217 /* 218 * Check for write permissions on the specified vnode. 219 * Prototype text segments cannot be written. 220 */ 221 int 222 vn_writechk(struct vnode *vp) 223 { 224 225 /* 226 * If the vnode is in use as a process's text, 227 * we can't allow writing. 228 */ 229 if (vp->v_flag & VTEXT) 230 return (ETXTBSY); 231 return (0); 232 } 233 234 /* 235 * Mark a vnode as having executable mappings. 236 */ 237 void 238 vn_markexec(struct vnode *vp) 239 { 240 if ((vp->v_flag & VEXECMAP) == 0) { 241 uvmexp.filepages -= vp->v_uobj.uo_npages; 242 uvmexp.execpages += vp->v_uobj.uo_npages; 243 } 244 vp->v_flag |= VEXECMAP; 245 } 246 247 /* 248 * Mark a vnode as being the text of a process. 249 * Fail if the vnode is currently writable. 250 */ 251 int 252 vn_marktext(struct vnode *vp) 253 { 254 255 if (vp->v_writecount != 0) { 256 KASSERT((vp->v_flag & VTEXT) == 0); 257 return (ETXTBSY); 258 } 259 vp->v_flag |= VTEXT; 260 vn_markexec(vp); 261 return (0); 262 } 263 264 /* 265 * Vnode close call 266 * 267 * Note: takes an unlocked vnode, while VOP_CLOSE takes a locked node. 268 */ 269 int 270 vn_close(struct vnode *vp, int flags, kauth_cred_t cred, struct lwp *l) 271 { 272 int error; 273 274 if (flags & FWRITE) 275 vp->v_writecount--; 276 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 277 error = VOP_CLOSE(vp, flags, cred, l); 278 vput(vp); 279 return (error); 280 } 281 282 /* 283 * Package up an I/O request on a vnode into a uio and do it. 284 */ 285 int 286 vn_rdwr(enum uio_rw rw, struct vnode *vp, void *base, int len, off_t offset, 287 enum uio_seg segflg, int ioflg, kauth_cred_t cred, size_t *aresid, 288 struct lwp *l) 289 { 290 struct uio auio; 291 struct iovec aiov; 292 int error; 293 294 if ((ioflg & IO_NODELOCKED) == 0) { 295 if (rw == UIO_READ) { 296 vn_lock(vp, LK_SHARED | LK_RETRY); 297 } else /* UIO_WRITE */ { 298 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 299 } 300 } 301 auio.uio_iov = &aiov; 302 auio.uio_iovcnt = 1; 303 aiov.iov_base = base; 304 aiov.iov_len = len; 305 auio.uio_resid = len; 306 auio.uio_offset = offset; 307 auio.uio_rw = rw; 308 if (segflg == UIO_SYSSPACE) { 309 UIO_SETUP_SYSSPACE(&auio); 310 } else { 311 auio.uio_vmspace = l->l_proc->p_vmspace; 312 } 313 if (rw == UIO_READ) { 314 error = VOP_READ(vp, &auio, ioflg, cred); 315 } else { 316 error = VOP_WRITE(vp, &auio, ioflg, cred); 317 } 318 if (aresid) 319 *aresid = auio.uio_resid; 320 else 321 if (auio.uio_resid && error == 0) 322 error = EIO; 323 if ((ioflg & IO_NODELOCKED) == 0) { 324 VOP_UNLOCK(vp, 0); 325 } 326 return (error); 327 } 328 329 int 330 vn_readdir(struct file *fp, char *bf, int segflg, u_int count, int *done, 331 struct lwp *l, off_t **cookies, int *ncookies) 332 { 333 struct vnode *vp = (struct vnode *)fp->f_data; 334 struct iovec aiov; 335 struct uio auio; 336 int error, eofflag; 337 338 /* Limit the size on any kernel buffers used by VOP_READDIR */ 339 count = min(MAXBSIZE, count); 340 341 unionread: 342 if (vp->v_type != VDIR) 343 return (EINVAL); 344 aiov.iov_base = bf; 345 aiov.iov_len = count; 346 auio.uio_iov = &aiov; 347 auio.uio_iovcnt = 1; 348 auio.uio_rw = UIO_READ; 349 if (segflg == UIO_SYSSPACE) { 350 UIO_SETUP_SYSSPACE(&auio); 351 } else { 352 KASSERT(l == curlwp); 353 auio.uio_vmspace = l->l_proc->p_vmspace; 354 } 355 auio.uio_resid = count; 356 vn_lock(vp, LK_SHARED | LK_RETRY); 357 auio.uio_offset = fp->f_offset; 358 error = VOP_READDIR(vp, &auio, fp->f_cred, &eofflag, cookies, 359 ncookies); 360 fp->f_offset = auio.uio_offset; 361 VOP_UNLOCK(vp, 0); 362 if (error) 363 return (error); 364 365 #if defined(UNION) || defined(LKM) 366 if (count == auio.uio_resid && vn_union_readdir_hook) { 367 struct vnode *ovp = vp; 368 369 error = (*vn_union_readdir_hook)(&vp, fp, l); 370 if (error) 371 return (error); 372 if (vp != ovp) 373 goto unionread; 374 } 375 #endif /* UNION || LKM */ 376 377 if (count == auio.uio_resid && (vp->v_flag & VROOT) && 378 (vp->v_mount->mnt_flag & MNT_UNION)) { 379 struct vnode *tvp = vp; 380 vp = vp->v_mount->mnt_vnodecovered; 381 VREF(vp); 382 fp->f_data = vp; 383 fp->f_offset = 0; 384 vrele(tvp); 385 goto unionread; 386 } 387 *done = count - auio.uio_resid; 388 return error; 389 } 390 391 /* 392 * File table vnode read routine. 393 */ 394 static int 395 vn_read(struct file *fp, off_t *offset, struct uio *uio, kauth_cred_t cred, 396 int flags) 397 { 398 struct vnode *vp = (struct vnode *)fp->f_data; 399 int count, error, ioflag; 400 struct lwp *l = curlwp; 401 402 VOP_LEASE(vp, l, cred, LEASE_READ); 403 ioflag = IO_ADV_ENCODE(fp->f_advice); 404 if (fp->f_flag & FNONBLOCK) 405 ioflag |= IO_NDELAY; 406 if ((fp->f_flag & (FFSYNC | FRSYNC)) == (FFSYNC | FRSYNC)) 407 ioflag |= IO_SYNC; 408 if (fp->f_flag & FALTIO) 409 ioflag |= IO_ALTSEMANTICS; 410 if (fp->f_flag & FDIRECT) 411 ioflag |= IO_DIRECT; 412 vn_lock(vp, LK_SHARED | LK_RETRY); 413 uio->uio_offset = *offset; 414 count = uio->uio_resid; 415 error = VOP_READ(vp, uio, ioflag, cred); 416 if (flags & FOF_UPDATE_OFFSET) 417 *offset += count - uio->uio_resid; 418 VOP_UNLOCK(vp, 0); 419 return (error); 420 } 421 422 /* 423 * File table vnode write routine. 424 */ 425 static int 426 vn_write(struct file *fp, off_t *offset, struct uio *uio, kauth_cred_t cred, 427 int flags) 428 { 429 struct vnode *vp = (struct vnode *)fp->f_data; 430 int count, error, ioflag = IO_UNIT; 431 struct lwp *l = curlwp; 432 433 if (vp->v_type == VREG && (fp->f_flag & O_APPEND)) 434 ioflag |= IO_APPEND; 435 if (fp->f_flag & FNONBLOCK) 436 ioflag |= IO_NDELAY; 437 if (fp->f_flag & FFSYNC || 438 (vp->v_mount && (vp->v_mount->mnt_flag & MNT_SYNCHRONOUS))) 439 ioflag |= IO_SYNC; 440 else if (fp->f_flag & FDSYNC) 441 ioflag |= IO_DSYNC; 442 if (fp->f_flag & FALTIO) 443 ioflag |= IO_ALTSEMANTICS; 444 if (fp->f_flag & FDIRECT) 445 ioflag |= IO_DIRECT; 446 VOP_LEASE(vp, l, cred, LEASE_WRITE); 447 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 448 uio->uio_offset = *offset; 449 count = uio->uio_resid; 450 error = VOP_WRITE(vp, uio, ioflag, cred); 451 if (flags & FOF_UPDATE_OFFSET) { 452 if (ioflag & IO_APPEND) 453 *offset = uio->uio_offset; 454 else 455 *offset += count - uio->uio_resid; 456 } 457 VOP_UNLOCK(vp, 0); 458 return (error); 459 } 460 461 /* 462 * File table vnode stat routine. 463 */ 464 static int 465 vn_statfile(struct file *fp, struct stat *sb, struct lwp *l) 466 { 467 struct vnode *vp = (struct vnode *)fp->f_data; 468 469 return vn_stat(vp, sb, l); 470 } 471 472 int 473 vn_stat(struct vnode *vp, struct stat *sb, struct lwp *l) 474 { 475 struct vattr va; 476 int error; 477 mode_t mode; 478 479 error = VOP_GETATTR(vp, &va, l->l_cred, l); 480 if (error) 481 return (error); 482 /* 483 * Copy from vattr table 484 */ 485 sb->st_dev = va.va_fsid; 486 sb->st_ino = va.va_fileid; 487 mode = va.va_mode; 488 switch (vp->v_type) { 489 case VREG: 490 mode |= S_IFREG; 491 break; 492 case VDIR: 493 mode |= S_IFDIR; 494 break; 495 case VBLK: 496 mode |= S_IFBLK; 497 break; 498 case VCHR: 499 mode |= S_IFCHR; 500 break; 501 case VLNK: 502 mode |= S_IFLNK; 503 break; 504 case VSOCK: 505 mode |= S_IFSOCK; 506 break; 507 case VFIFO: 508 mode |= S_IFIFO; 509 break; 510 default: 511 return (EBADF); 512 }; 513 sb->st_mode = mode; 514 sb->st_nlink = va.va_nlink; 515 sb->st_uid = va.va_uid; 516 sb->st_gid = va.va_gid; 517 sb->st_rdev = va.va_rdev; 518 sb->st_size = va.va_size; 519 sb->st_atimespec = va.va_atime; 520 sb->st_mtimespec = va.va_mtime; 521 sb->st_ctimespec = va.va_ctime; 522 sb->st_birthtimespec = va.va_birthtime; 523 sb->st_blksize = va.va_blocksize; 524 sb->st_flags = va.va_flags; 525 sb->st_gen = 0; 526 sb->st_blocks = va.va_bytes / S_BLKSIZE; 527 return (0); 528 } 529 530 /* 531 * File table vnode fcntl routine. 532 */ 533 static int 534 vn_fcntl(struct file *fp, u_int com, void *data, struct lwp *l) 535 { 536 struct vnode *vp = ((struct vnode *)fp->f_data); 537 int error; 538 539 error = VOP_FCNTL(vp, com, data, fp->f_flag, l->l_cred, l); 540 return (error); 541 } 542 543 /* 544 * File table vnode ioctl routine. 545 */ 546 static int 547 vn_ioctl(struct file *fp, u_long com, void *data, struct lwp *l) 548 { 549 struct vnode *vp = ((struct vnode *)fp->f_data), *ovp; 550 struct proc *p = l->l_proc; 551 struct vattr vattr; 552 int error; 553 554 switch (vp->v_type) { 555 556 case VREG: 557 case VDIR: 558 if (com == FIONREAD) { 559 error = VOP_GETATTR(vp, &vattr, l->l_cred, l); 560 if (error) 561 return (error); 562 *(int *)data = vattr.va_size - fp->f_offset; 563 return (0); 564 } 565 if ((com == FIONWRITE) || (com == FIONSPACE)) { 566 /* 567 * Files don't have send queues, so there never 568 * are any bytes in them, nor is there any 569 * open space in them. 570 */ 571 *(int *)data = 0; 572 return (0); 573 } 574 if (com == FIOGETBMAP) { 575 daddr_t *block; 576 577 if (*(daddr_t *)data < 0) 578 return (EINVAL); 579 block = (daddr_t *)data; 580 return (VOP_BMAP(vp, *block, NULL, block, NULL)); 581 } 582 if (com == OFIOGETBMAP) { 583 daddr_t ibn, obn; 584 585 if (*(int32_t *)data < 0) 586 return (EINVAL); 587 ibn = (daddr_t)*(int32_t *)data; 588 error = VOP_BMAP(vp, ibn, NULL, &obn, NULL); 589 *(int32_t *)data = (int32_t)obn; 590 return error; 591 } 592 if (com == FIONBIO || com == FIOASYNC) /* XXX */ 593 return (0); /* XXX */ 594 /* fall into ... */ 595 case VFIFO: 596 case VCHR: 597 case VBLK: 598 error = VOP_IOCTL(vp, com, data, fp->f_flag, 599 l->l_cred, l); 600 if (error == 0 && com == TIOCSCTTY) { 601 VREF(vp); 602 mutex_enter(&proclist_lock); 603 ovp = p->p_session->s_ttyvp; 604 p->p_session->s_ttyvp = vp; 605 mutex_exit(&proclist_lock); 606 if (ovp != NULL) 607 vrele(ovp); 608 } 609 return (error); 610 611 default: 612 return (EPASSTHROUGH); 613 } 614 } 615 616 /* 617 * File table vnode poll routine. 618 */ 619 static int 620 vn_poll(struct file *fp, int events, struct lwp *l) 621 { 622 623 return (VOP_POLL(((struct vnode *)fp->f_data), events, l)); 624 } 625 626 /* 627 * File table vnode kqfilter routine. 628 */ 629 int 630 vn_kqfilter(struct file *fp, struct knote *kn) 631 { 632 633 return (VOP_KQFILTER((struct vnode *)fp->f_data, kn)); 634 } 635 636 /* 637 * Check that the vnode is still valid, and if so 638 * acquire requested lock. 639 */ 640 int 641 vn_lock(struct vnode *vp, int flags) 642 { 643 int error; 644 645 #if 0 646 KASSERT(vp->v_usecount > 0 || (flags & LK_INTERLOCK) != 0 647 || (vp->v_flag & VONWORKLST) != 0); 648 #endif 649 KASSERT((flags & 650 ~(LK_INTERLOCK|LK_SHARED|LK_EXCLUSIVE|LK_DRAIN|LK_NOWAIT|LK_RETRY| 651 LK_SETRECURSE|LK_CANRECURSE)) 652 == 0); 653 654 do { 655 if ((flags & LK_INTERLOCK) == 0) 656 simple_lock(&vp->v_interlock); 657 if (vp->v_flag & VXLOCK) { 658 if (flags & LK_NOWAIT) { 659 simple_unlock(&vp->v_interlock); 660 return EBUSY; 661 } 662 vp->v_flag |= VXWANT; 663 ltsleep(vp, PINOD | PNORELOCK, 664 "vn_lock", 0, &vp->v_interlock); 665 error = ENOENT; 666 } else { 667 error = VOP_LOCK(vp, 668 (flags & ~LK_RETRY) | LK_INTERLOCK); 669 if (error == 0 || error == EDEADLK || error == EBUSY) 670 return (error); 671 } 672 flags &= ~LK_INTERLOCK; 673 } while (flags & LK_RETRY); 674 return (error); 675 } 676 677 /* 678 * File table vnode close routine. 679 */ 680 static int 681 vn_closefile(struct file *fp, struct lwp *l) 682 { 683 684 return (vn_close(((struct vnode *)fp->f_data), fp->f_flag, 685 fp->f_cred, l)); 686 } 687 688 /* 689 * Enable LK_CANRECURSE on lock. Return prior status. 690 */ 691 u_int 692 vn_setrecurse(struct vnode *vp) 693 { 694 struct lock *lkp = &vp->v_lock; 695 u_int retval = lkp->lk_flags & LK_CANRECURSE; 696 697 lkp->lk_flags |= LK_CANRECURSE; 698 return retval; 699 } 700 701 /* 702 * Called when done with locksetrecurse. 703 */ 704 void 705 vn_restorerecurse(struct vnode *vp, u_int flags) 706 { 707 struct lock *lkp = &vp->v_lock; 708 709 lkp->lk_flags &= ~LK_CANRECURSE; 710 lkp->lk_flags |= flags; 711 } 712 713 /* 714 * Obsolete: this function will be removed from 6.0 715 * Please use fscow_establish() instead. 716 */ 717 int 718 vn_cow_establish(struct vnode *vp, 719 int (*func)(void *, struct buf *), void *cookie) 720 { 721 static int firstrun = 1; 722 723 if (firstrun) { 724 printf("%s: this function is obsolete.\n", __FUNCTION__); 725 firstrun = 0; 726 } 727 if (vp->v_type == VBLK) 728 return fscow_establish(vp->v_specmountpoint, func, cookie); 729 else 730 return fscow_establish(vp->v_mount, func, cookie); 731 } 732 733 /* 734 * Obsolete: this function will be removed from 6.0 735 * Please use fscow_disestablish() instead. 736 */ 737 int 738 vn_cow_disestablish(struct vnode *vp, 739 int (*func)(void *, struct buf *), void *cookie) 740 { 741 if (vp->v_type == VBLK) 742 return fscow_disestablish(vp->v_specmountpoint, func, cookie); 743 else 744 return fscow_disestablish(vp->v_mount, func, cookie); 745 } 746 747 /* 748 * Simplified in-kernel wrapper calls for extended attribute access. 749 * Both calls pass in a NULL credential, authorizing a "kernel" access. 750 * Set IO_NODELOCKED in ioflg if the vnode is already locked. 751 */ 752 int 753 vn_extattr_get(struct vnode *vp, int ioflg, int attrnamespace, 754 const char *attrname, size_t *buflen, void *bf, struct lwp *l) 755 { 756 struct uio auio; 757 struct iovec aiov; 758 int error; 759 760 aiov.iov_len = *buflen; 761 aiov.iov_base = bf; 762 763 auio.uio_iov = &aiov; 764 auio.uio_iovcnt = 1; 765 auio.uio_rw = UIO_READ; 766 auio.uio_offset = 0; 767 auio.uio_resid = *buflen; 768 UIO_SETUP_SYSSPACE(&auio); 769 770 if ((ioflg & IO_NODELOCKED) == 0) 771 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 772 773 error = VOP_GETEXTATTR(vp, attrnamespace, attrname, &auio, NULL, NULL, 774 l); 775 776 if ((ioflg & IO_NODELOCKED) == 0) 777 VOP_UNLOCK(vp, 0); 778 779 if (error == 0) 780 *buflen = *buflen - auio.uio_resid; 781 782 return (error); 783 } 784 785 /* 786 * XXX Failure mode if partially written? 787 */ 788 int 789 vn_extattr_set(struct vnode *vp, int ioflg, int attrnamespace, 790 const char *attrname, size_t buflen, const void *bf, struct lwp *l) 791 { 792 struct uio auio; 793 struct iovec aiov; 794 int error; 795 796 aiov.iov_len = buflen; 797 aiov.iov_base = __UNCONST(bf); /* XXXUNCONST kills const */ 798 799 auio.uio_iov = &aiov; 800 auio.uio_iovcnt = 1; 801 auio.uio_rw = UIO_WRITE; 802 auio.uio_offset = 0; 803 auio.uio_resid = buflen; 804 UIO_SETUP_SYSSPACE(&auio); 805 806 if ((ioflg & IO_NODELOCKED) == 0) { 807 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 808 } 809 810 error = VOP_SETEXTATTR(vp, attrnamespace, attrname, &auio, NULL, l); 811 812 if ((ioflg & IO_NODELOCKED) == 0) { 813 VOP_UNLOCK(vp, 0); 814 } 815 816 return (error); 817 } 818 819 int 820 vn_extattr_rm(struct vnode *vp, int ioflg, int attrnamespace, 821 const char *attrname, struct lwp *l) 822 { 823 int error; 824 825 if ((ioflg & IO_NODELOCKED) == 0) { 826 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 827 } 828 829 error = VOP_DELETEEXTATTR(vp, attrnamespace, attrname, NULL, l); 830 if (error == EOPNOTSUPP) 831 error = VOP_SETEXTATTR(vp, attrnamespace, attrname, NULL, 832 NULL, l); 833 834 if ((ioflg & IO_NODELOCKED) == 0) { 835 VOP_UNLOCK(vp, 0); 836 } 837 838 return (error); 839 } 840 841 void 842 vn_ra_allocctx(struct vnode *vp) 843 { 844 struct uvm_ractx *ra = NULL; 845 846 if (vp->v_type != VREG) { 847 return; 848 } 849 if (vp->v_ractx != NULL) { 850 return; 851 } 852 simple_lock(&vp->v_interlock); 853 if (vp->v_ractx == NULL) { 854 simple_unlock(&vp->v_interlock); 855 ra = uvm_ra_allocctx(); 856 simple_lock(&vp->v_interlock); 857 if (ra != NULL && vp->v_ractx == NULL) { 858 vp->v_ractx = ra; 859 ra = NULL; 860 } 861 } 862 simple_unlock(&vp->v_interlock); 863 if (ra != NULL) { 864 uvm_ra_freectx(ra); 865 } 866 } 867
Indexes created Sat Sep 20 22:09:52 GMT 2025