vfs_vnops.c revision 1.155.2.2
1 /* $NetBSD: vfs_vnops.c,v 1.155.2.2 2008/06/04 02:05:40 yamt 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 1.155.2.2 2008/06/04 02:05:40 yamt 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 #include <sys/atomic.h> 63 #include <sys/filedesc.h> 64 65 #include <miscfs/specfs/specdev.h> 66 67 #include <uvm/uvm_extern.h> 68 #include <uvm/uvm_readahead.h> 69 70 #ifdef UNION 71 #include <fs/union/union.h> 72 #endif 73 74 #if defined(LKM) || defined(UNION) 75 int (*vn_union_readdir_hook) (struct vnode **, struct file *, struct lwp *); 76 #endif 77 78 #include <sys/verified_exec.h> 79 80 static int vn_read(file_t *fp, off_t *offset, struct uio *uio, 81 kauth_cred_t cred, int flags); 82 static int vn_write(file_t *fp, off_t *offset, struct uio *uio, 83 kauth_cred_t cred, int flags); 84 static int vn_closefile(file_t *fp); 85 static int vn_poll(file_t *fp, int events); 86 static int vn_fcntl(file_t *fp, u_int com, void *data); 87 static int vn_statfile(file_t *fp, struct stat *sb); 88 static int vn_ioctl(file_t *fp, u_long com, void *data); 89 90 const struct fileops vnops = { 91 vn_read, vn_write, vn_ioctl, vn_fcntl, vn_poll, 92 vn_statfile, vn_closefile, vn_kqfilter 93 }; 94 95 /* 96 * Common code for vnode open operations. 97 * Check permissions, and call the VOP_OPEN or VOP_CREATE routine. 98 */ 99 int 100 vn_open(struct nameidata *ndp, int fmode, int cmode) 101 { 102 struct vnode *vp; 103 struct lwp *l = curlwp; 104 kauth_cred_t cred = l->l_cred; 105 struct vattr va; 106 int error; 107 char *path; 108 109 ndp->ni_cnd.cn_flags &= TRYEMULROOT; 110 111 if (fmode & O_CREAT) { 112 ndp->ni_cnd.cn_nameiop = CREATE; 113 ndp->ni_cnd.cn_flags |= LOCKPARENT | LOCKLEAF; 114 if ((fmode & O_EXCL) == 0 && 115 ((fmode & O_NOFOLLOW) == 0)) 116 ndp->ni_cnd.cn_flags |= FOLLOW; 117 } else { 118 ndp->ni_cnd.cn_nameiop = LOOKUP; 119 ndp->ni_cnd.cn_flags |= LOCKLEAF; 120 if ((fmode & O_NOFOLLOW) == 0) 121 ndp->ni_cnd.cn_flags |= FOLLOW; 122 } 123 124 VERIEXEC_PATH_GET(ndp->ni_dirp, ndp->ni_segflg, ndp->ni_dirp, path); 125 126 error = namei(ndp); 127 if (error) 128 goto out; 129 130 vp = ndp->ni_vp; 131 132 #if NVERIEXEC > 0 133 error = veriexec_openchk(l, ndp->ni_vp, ndp->ni_dirp, fmode); 134 if (error) 135 goto bad; 136 #endif /* NVERIEXEC > 0 */ 137 138 if (fmode & O_CREAT) { 139 if (ndp->ni_vp == NULL) { 140 VATTR_NULL(&va); 141 va.va_type = VREG; 142 va.va_mode = cmode; 143 if (fmode & O_EXCL) 144 va.va_vaflags |= VA_EXCLUSIVE; 145 error = VOP_CREATE(ndp->ni_dvp, &ndp->ni_vp, 146 &ndp->ni_cnd, &va); 147 if (error) 148 goto out; 149 fmode &= ~O_TRUNC; 150 vp = ndp->ni_vp; 151 } else { 152 VOP_ABORTOP(ndp->ni_dvp, &ndp->ni_cnd); 153 if (ndp->ni_dvp == ndp->ni_vp) 154 vrele(ndp->ni_dvp); 155 else 156 vput(ndp->ni_dvp); 157 ndp->ni_dvp = NULL; 158 vp = ndp->ni_vp; 159 if (fmode & O_EXCL) { 160 error = EEXIST; 161 goto bad; 162 } 163 fmode &= ~O_CREAT; 164 } 165 } else { 166 vp = ndp->ni_vp; 167 } 168 if (vp->v_type == VSOCK) { 169 error = EOPNOTSUPP; 170 goto bad; 171 } 172 if (ndp->ni_vp->v_type == VLNK) { 173 error = EFTYPE; 174 goto bad; 175 } 176 177 if ((fmode & O_CREAT) == 0) { 178 error = vn_openchk(vp, cred, fmode); 179 if (error != 0) 180 goto bad; 181 } 182 183 if (fmode & O_TRUNC) { 184 VOP_UNLOCK(vp, 0); /* XXX */ 185 186 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); /* XXX */ 187 VATTR_NULL(&va); 188 va.va_size = 0; 189 error = VOP_SETATTR(vp, &va, cred); 190 if (error != 0) 191 goto bad; 192 } 193 if ((error = VOP_OPEN(vp, fmode, cred)) != 0) 194 goto bad; 195 if (fmode & FWRITE) { 196 mutex_enter(&vp->v_interlock); 197 vp->v_writecount++; 198 mutex_exit(&vp->v_interlock); 199 } 200 201 bad: 202 if (error) 203 vput(vp); 204 out: 205 VERIEXEC_PATH_PUT(path); 206 return (error); 207 } 208 209 /* 210 * Check for write permissions on the specified vnode. 211 * Prototype text segments cannot be written. 212 */ 213 int 214 vn_writechk(struct vnode *vp) 215 { 216 217 /* 218 * If the vnode is in use as a process's text, 219 * we can't allow writing. 220 */ 221 if (vp->v_iflag & VI_TEXT) 222 return (ETXTBSY); 223 return (0); 224 } 225 226 int 227 vn_openchk(struct vnode *vp, kauth_cred_t cred, int fflags) 228 { 229 int permbits = 0; 230 int error; 231 232 if ((fflags & FREAD) != 0) { 233 permbits = VREAD; 234 } 235 if ((fflags & (FWRITE | O_TRUNC)) != 0) { 236 permbits |= VWRITE; 237 if (vp->v_type == VDIR) { 238 error = EISDIR; 239 goto bad; 240 } 241 error = vn_writechk(vp); 242 if (error != 0) 243 goto bad; 244 } 245 error = VOP_ACCESS(vp, permbits, cred); 246 bad: 247 return error; 248 } 249 250 /* 251 * Mark a vnode as having executable mappings. 252 */ 253 void 254 vn_markexec(struct vnode *vp) 255 { 256 257 if ((vp->v_iflag & VI_EXECMAP) != 0) { 258 /* Safe unlocked, as long as caller holds a reference. */ 259 return; 260 } 261 262 mutex_enter(&vp->v_interlock); 263 if ((vp->v_iflag & VI_EXECMAP) == 0) { 264 atomic_add_int(&uvmexp.filepages, -vp->v_uobj.uo_npages); 265 atomic_add_int(&uvmexp.execpages, vp->v_uobj.uo_npages); 266 vp->v_iflag |= VI_EXECMAP; 267 } 268 mutex_exit(&vp->v_interlock); 269 } 270 271 /* 272 * Mark a vnode as being the text of a process. 273 * Fail if the vnode is currently writable. 274 */ 275 int 276 vn_marktext(struct vnode *vp) 277 { 278 279 if ((vp->v_iflag & (VI_TEXT|VI_EXECMAP)) == (VI_TEXT|VI_EXECMAP)) { 280 /* Safe unlocked, as long as caller holds a reference. */ 281 return (0); 282 } 283 284 mutex_enter(&vp->v_interlock); 285 if (vp->v_writecount != 0) { 286 KASSERT((vp->v_iflag & VI_TEXT) == 0); 287 mutex_exit(&vp->v_interlock); 288 return (ETXTBSY); 289 } 290 if ((vp->v_iflag & VI_EXECMAP) == 0) { 291 atomic_add_int(&uvmexp.filepages, -vp->v_uobj.uo_npages); 292 atomic_add_int(&uvmexp.execpages, vp->v_uobj.uo_npages); 293 } 294 vp->v_iflag |= (VI_TEXT | VI_EXECMAP); 295 mutex_exit(&vp->v_interlock); 296 return (0); 297 } 298 299 /* 300 * Vnode close call 301 * 302 * Note: takes an unlocked vnode, while VOP_CLOSE takes a locked node. 303 */ 304 int 305 vn_close(struct vnode *vp, int flags, kauth_cred_t cred) 306 { 307 int error; 308 309 if (flags & FWRITE) { 310 mutex_enter(&vp->v_interlock); 311 vp->v_writecount--; 312 mutex_exit(&vp->v_interlock); 313 } 314 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 315 error = VOP_CLOSE(vp, flags, cred); 316 vput(vp); 317 return (error); 318 } 319 320 /* 321 * Package up an I/O request on a vnode into a uio and do it. 322 */ 323 int 324 vn_rdwr(enum uio_rw rw, struct vnode *vp, void *base, int len, off_t offset, 325 enum uio_seg segflg, int ioflg, kauth_cred_t cred, size_t *aresid, 326 struct lwp *l) 327 { 328 struct uio auio; 329 struct iovec aiov; 330 int error; 331 332 if ((ioflg & IO_NODELOCKED) == 0) { 333 if (rw == UIO_READ) { 334 vn_lock(vp, LK_SHARED | LK_RETRY); 335 } else /* UIO_WRITE */ { 336 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 337 } 338 } 339 auio.uio_iov = &aiov; 340 auio.uio_iovcnt = 1; 341 aiov.iov_base = base; 342 aiov.iov_len = len; 343 auio.uio_resid = len; 344 auio.uio_offset = offset; 345 auio.uio_rw = rw; 346 if (segflg == UIO_SYSSPACE) { 347 UIO_SETUP_SYSSPACE(&auio); 348 } else { 349 auio.uio_vmspace = l->l_proc->p_vmspace; 350 } 351 if (rw == UIO_READ) { 352 error = VOP_READ(vp, &auio, ioflg, cred); 353 } else { 354 error = VOP_WRITE(vp, &auio, ioflg, cred); 355 } 356 if (aresid) 357 *aresid = auio.uio_resid; 358 else 359 if (auio.uio_resid && error == 0) 360 error = EIO; 361 if ((ioflg & IO_NODELOCKED) == 0) { 362 VOP_UNLOCK(vp, 0); 363 } 364 return (error); 365 } 366 367 int 368 vn_readdir(file_t *fp, char *bf, int segflg, u_int count, int *done, 369 struct lwp *l, off_t **cookies, int *ncookies) 370 { 371 struct vnode *vp = (struct vnode *)fp->f_data; 372 struct iovec aiov; 373 struct uio auio; 374 int error, eofflag; 375 376 /* Limit the size on any kernel buffers used by VOP_READDIR */ 377 count = min(MAXBSIZE, count); 378 379 unionread: 380 if (vp->v_type != VDIR) 381 return (EINVAL); 382 aiov.iov_base = bf; 383 aiov.iov_len = count; 384 auio.uio_iov = &aiov; 385 auio.uio_iovcnt = 1; 386 auio.uio_rw = UIO_READ; 387 if (segflg == UIO_SYSSPACE) { 388 UIO_SETUP_SYSSPACE(&auio); 389 } else { 390 KASSERT(l == curlwp); 391 auio.uio_vmspace = l->l_proc->p_vmspace; 392 } 393 auio.uio_resid = count; 394 vn_lock(vp, LK_SHARED | LK_RETRY); 395 auio.uio_offset = fp->f_offset; 396 error = VOP_READDIR(vp, &auio, fp->f_cred, &eofflag, cookies, 397 ncookies); 398 FILE_LOCK(fp); 399 fp->f_offset = auio.uio_offset; 400 FILE_UNLOCK(fp); 401 VOP_UNLOCK(vp, 0); 402 if (error) 403 return (error); 404 405 #if defined(UNION) || defined(LKM) 406 if (count == auio.uio_resid && vn_union_readdir_hook) { 407 struct vnode *ovp = vp; 408 409 error = (*vn_union_readdir_hook)(&vp, fp, l); 410 if (error) 411 return (error); 412 if (vp != ovp) 413 goto unionread; 414 } 415 #endif /* UNION || LKM */ 416 417 if (count == auio.uio_resid && (vp->v_vflag & VV_ROOT) && 418 (vp->v_mount->mnt_flag & MNT_UNION)) { 419 struct vnode *tvp = vp; 420 vp = vp->v_mount->mnt_vnodecovered; 421 VREF(vp); 422 FILE_LOCK(fp); 423 fp->f_data = vp; 424 fp->f_offset = 0; 425 FILE_UNLOCK(fp); 426 vrele(tvp); 427 goto unionread; 428 } 429 *done = count - auio.uio_resid; 430 return error; 431 } 432 433 /* 434 * File table vnode read routine. 435 */ 436 static int 437 vn_read(file_t *fp, off_t *offset, struct uio *uio, kauth_cred_t cred, 438 int flags) 439 { 440 struct vnode *vp = (struct vnode *)fp->f_data; 441 int count, error, ioflag, fflag; 442 443 ioflag = IO_ADV_ENCODE(fp->f_advice); 444 fflag = fp->f_flag; 445 if (fflag & FNONBLOCK) 446 ioflag |= IO_NDELAY; 447 if ((fflag & (FFSYNC | FRSYNC)) == (FFSYNC | FRSYNC)) 448 ioflag |= IO_SYNC; 449 if (fflag & FALTIO) 450 ioflag |= IO_ALTSEMANTICS; 451 if (fflag & FDIRECT) 452 ioflag |= IO_DIRECT; 453 vn_lock(vp, LK_SHARED | LK_RETRY); 454 uio->uio_offset = *offset; 455 count = uio->uio_resid; 456 error = VOP_READ(vp, uio, ioflag, cred); 457 if (flags & FOF_UPDATE_OFFSET) 458 *offset += count - uio->uio_resid; 459 VOP_UNLOCK(vp, 0); 460 return (error); 461 } 462 463 /* 464 * File table vnode write routine. 465 */ 466 static int 467 vn_write(file_t *fp, off_t *offset, struct uio *uio, kauth_cred_t cred, 468 int flags) 469 { 470 struct vnode *vp = (struct vnode *)fp->f_data; 471 int count, error, ioflag, fflag; 472 473 ioflag = IO_ADV_ENCODE(fp->f_advice) | IO_UNIT; 474 fflag = fp->f_flag; 475 if (vp->v_type == VREG && (fflag & O_APPEND)) 476 ioflag |= IO_APPEND; 477 if (fflag & FNONBLOCK) 478 ioflag |= IO_NDELAY; 479 if (fflag & FFSYNC || 480 (vp->v_mount && (vp->v_mount->mnt_flag & MNT_SYNCHRONOUS))) 481 ioflag |= IO_SYNC; 482 else if (fflag & FDSYNC) 483 ioflag |= IO_DSYNC; 484 if (fflag & FALTIO) 485 ioflag |= IO_ALTSEMANTICS; 486 if (fflag & FDIRECT) 487 ioflag |= IO_DIRECT; 488 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 489 uio->uio_offset = *offset; 490 count = uio->uio_resid; 491 error = VOP_WRITE(vp, uio, ioflag, cred); 492 if (flags & FOF_UPDATE_OFFSET) { 493 if (ioflag & IO_APPEND) 494 *offset = uio->uio_offset; 495 else 496 *offset += count - uio->uio_resid; 497 } 498 VOP_UNLOCK(vp, 0); 499 return (error); 500 } 501 502 /* 503 * File table vnode stat routine. 504 */ 505 static int 506 vn_statfile(file_t *fp, struct stat *sb) 507 { 508 struct vnode *vp = (struct vnode *)fp->f_data; 509 510 return vn_stat(vp, sb); 511 } 512 513 int 514 vn_stat(struct vnode *vp, struct stat *sb) 515 { 516 struct vattr va; 517 int error; 518 mode_t mode; 519 520 error = VOP_GETATTR(vp, &va, kauth_cred_get()); 521 if (error) 522 return (error); 523 /* 524 * Copy from vattr table 525 */ 526 sb->st_dev = va.va_fsid; 527 sb->st_ino = va.va_fileid; 528 mode = va.va_mode; 529 switch (vp->v_type) { 530 case VREG: 531 mode |= S_IFREG; 532 break; 533 case VDIR: 534 mode |= S_IFDIR; 535 break; 536 case VBLK: 537 mode |= S_IFBLK; 538 break; 539 case VCHR: 540 mode |= S_IFCHR; 541 break; 542 case VLNK: 543 mode |= S_IFLNK; 544 break; 545 case VSOCK: 546 mode |= S_IFSOCK; 547 break; 548 case VFIFO: 549 mode |= S_IFIFO; 550 break; 551 default: 552 return (EBADF); 553 }; 554 sb->st_mode = mode; 555 sb->st_nlink = va.va_nlink; 556 sb->st_uid = va.va_uid; 557 sb->st_gid = va.va_gid; 558 sb->st_rdev = va.va_rdev; 559 sb->st_size = va.va_size; 560 sb->st_atimespec = va.va_atime; 561 sb->st_mtimespec = va.va_mtime; 562 sb->st_ctimespec = va.va_ctime; 563 sb->st_birthtimespec = va.va_birthtime; 564 sb->st_blksize = va.va_blocksize; 565 sb->st_flags = va.va_flags; 566 sb->st_gen = 0; 567 sb->st_blocks = va.va_bytes / S_BLKSIZE; 568 return (0); 569 } 570 571 /* 572 * File table vnode fcntl routine. 573 */ 574 static int 575 vn_fcntl(file_t *fp, u_int com, void *data) 576 { 577 struct vnode *vp = fp->f_data; 578 int error; 579 580 error = VOP_FCNTL(vp, com, data, fp->f_flag, kauth_cred_get()); 581 return (error); 582 } 583 584 /* 585 * File table vnode ioctl routine. 586 */ 587 static int 588 vn_ioctl(file_t *fp, u_long com, void *data) 589 { 590 struct vnode *vp = fp->f_data, *ovp; 591 struct vattr vattr; 592 int error; 593 594 switch (vp->v_type) { 595 596 case VREG: 597 case VDIR: 598 if (com == FIONREAD) { 599 error = VOP_GETATTR(vp, &vattr, 600 kauth_cred_get()); 601 if (error) 602 return (error); 603 *(int *)data = vattr.va_size - fp->f_offset; 604 return (0); 605 } 606 if ((com == FIONWRITE) || (com == FIONSPACE)) { 607 /* 608 * Files don't have send queues, so there never 609 * are any bytes in them, nor is there any 610 * open space in them. 611 */ 612 *(int *)data = 0; 613 return (0); 614 } 615 if (com == FIOGETBMAP) { 616 daddr_t *block; 617 618 if (*(daddr_t *)data < 0) 619 return (EINVAL); 620 block = (daddr_t *)data; 621 return (VOP_BMAP(vp, *block, NULL, block, NULL)); 622 } 623 if (com == OFIOGETBMAP) { 624 daddr_t ibn, obn; 625 626 if (*(int32_t *)data < 0) 627 return (EINVAL); 628 ibn = (daddr_t)*(int32_t *)data; 629 error = VOP_BMAP(vp, ibn, NULL, &obn, NULL); 630 *(int32_t *)data = (int32_t)obn; 631 return error; 632 } 633 if (com == FIONBIO || com == FIOASYNC) /* XXX */ 634 return (0); /* XXX */ 635 /* fall into ... */ 636 case VFIFO: 637 case VCHR: 638 case VBLK: 639 error = VOP_IOCTL(vp, com, data, fp->f_flag, 640 kauth_cred_get()); 641 if (error == 0 && com == TIOCSCTTY) { 642 VREF(vp); 643 mutex_enter(proc_lock); 644 ovp = curproc->p_session->s_ttyvp; 645 curproc->p_session->s_ttyvp = vp; 646 mutex_exit(proc_lock); 647 if (ovp != NULL) 648 vrele(ovp); 649 } 650 return (error); 651 652 default: 653 return (EPASSTHROUGH); 654 } 655 } 656 657 /* 658 * File table vnode poll routine. 659 */ 660 static int 661 vn_poll(file_t *fp, int events) 662 { 663 664 return (VOP_POLL(fp->f_data, events)); 665 } 666 667 /* 668 * File table vnode kqfilter routine. 669 */ 670 int 671 vn_kqfilter(file_t *fp, struct knote *kn) 672 { 673 674 return (VOP_KQFILTER(fp->f_data, kn)); 675 } 676 677 /* 678 * Check that the vnode is still valid, and if so 679 * acquire requested lock. 680 */ 681 int 682 vn_lock(struct vnode *vp, int flags) 683 { 684 int error; 685 686 #if 0 687 KASSERT(vp->v_usecount > 0 || (flags & LK_INTERLOCK) != 0 688 || (vp->v_iflag & VI_ONWORKLST) != 0); 689 #endif 690 KASSERT((flags & 691 ~(LK_INTERLOCK|LK_SHARED|LK_EXCLUSIVE|LK_NOWAIT|LK_RETRY| 692 LK_CANRECURSE)) 693 == 0); 694 695 do { 696 /* 697 * XXX PR 37706 forced unmount of file systems is unsafe. 698 * Race between vclean() and this the remaining problem. 699 */ 700 if (vp->v_iflag & VI_XLOCK) { 701 if ((flags & LK_INTERLOCK) == 0) { 702 mutex_enter(&vp->v_interlock); 703 } 704 flags &= ~LK_INTERLOCK; 705 if (flags & LK_NOWAIT) { 706 mutex_exit(&vp->v_interlock); 707 return EBUSY; 708 } 709 vwait(vp, VI_XLOCK); 710 mutex_exit(&vp->v_interlock); 711 error = ENOENT; 712 } else { 713 if ((flags & LK_INTERLOCK) != 0) { 714 mutex_exit(&vp->v_interlock); 715 } 716 flags &= ~LK_INTERLOCK; 717 error = VOP_LOCK(vp, (flags & ~LK_RETRY)); 718 if (error == 0 || error == EDEADLK || error == EBUSY) 719 return (error); 720 } 721 } while (flags & LK_RETRY); 722 return (error); 723 } 724 725 /* 726 * File table vnode close routine. 727 */ 728 static int 729 vn_closefile(file_t *fp) 730 { 731 732 return vn_close(fp->f_data, fp->f_flag, fp->f_cred); 733 } 734 735 /* 736 * Enable LK_CANRECURSE on lock. Return prior status. 737 */ 738 u_int 739 vn_setrecurse(struct vnode *vp) 740 { 741 struct vnlock *lkp; 742 743 lkp = (vp->v_vnlock != NULL ? vp->v_vnlock : &vp->v_lock); 744 atomic_inc_uint(&lkp->vl_canrecurse); 745 746 return 0; 747 } 748 749 /* 750 * Called when done with locksetrecurse. 751 */ 752 void 753 vn_restorerecurse(struct vnode *vp, u_int flags) 754 { 755 struct vnlock *lkp; 756 757 lkp = (vp->v_vnlock != NULL ? vp->v_vnlock : &vp->v_lock); 758 atomic_dec_uint(&lkp->vl_canrecurse); 759 } 760 761 /* 762 * Simplified in-kernel wrapper calls for extended attribute access. 763 * Both calls pass in a NULL credential, authorizing a "kernel" access. 764 * Set IO_NODELOCKED in ioflg if the vnode is already locked. 765 */ 766 int 767 vn_extattr_get(struct vnode *vp, int ioflg, int attrnamespace, 768 const char *attrname, size_t *buflen, void *bf, struct lwp *l) 769 { 770 struct uio auio; 771 struct iovec aiov; 772 int error; 773 774 aiov.iov_len = *buflen; 775 aiov.iov_base = bf; 776 777 auio.uio_iov = &aiov; 778 auio.uio_iovcnt = 1; 779 auio.uio_rw = UIO_READ; 780 auio.uio_offset = 0; 781 auio.uio_resid = *buflen; 782 UIO_SETUP_SYSSPACE(&auio); 783 784 if ((ioflg & IO_NODELOCKED) == 0) 785 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 786 787 error = VOP_GETEXTATTR(vp, attrnamespace, attrname, &auio, NULL, NULL); 788 789 if ((ioflg & IO_NODELOCKED) == 0) 790 VOP_UNLOCK(vp, 0); 791 792 if (error == 0) 793 *buflen = *buflen - auio.uio_resid; 794 795 return (error); 796 } 797 798 /* 799 * XXX Failure mode if partially written? 800 */ 801 int 802 vn_extattr_set(struct vnode *vp, int ioflg, int attrnamespace, 803 const char *attrname, size_t buflen, const void *bf, struct lwp *l) 804 { 805 struct uio auio; 806 struct iovec aiov; 807 int error; 808 809 aiov.iov_len = buflen; 810 aiov.iov_base = __UNCONST(bf); /* XXXUNCONST kills const */ 811 812 auio.uio_iov = &aiov; 813 auio.uio_iovcnt = 1; 814 auio.uio_rw = UIO_WRITE; 815 auio.uio_offset = 0; 816 auio.uio_resid = buflen; 817 UIO_SETUP_SYSSPACE(&auio); 818 819 if ((ioflg & IO_NODELOCKED) == 0) { 820 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 821 } 822 823 error = VOP_SETEXTATTR(vp, attrnamespace, attrname, &auio, NULL); 824 825 if ((ioflg & IO_NODELOCKED) == 0) { 826 VOP_UNLOCK(vp, 0); 827 } 828 829 return (error); 830 } 831 832 int 833 vn_extattr_rm(struct vnode *vp, int ioflg, int attrnamespace, 834 const char *attrname, struct lwp *l) 835 { 836 int error; 837 838 if ((ioflg & IO_NODELOCKED) == 0) { 839 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 840 } 841 842 error = VOP_DELETEEXTATTR(vp, attrnamespace, attrname, NULL); 843 if (error == EOPNOTSUPP) 844 error = VOP_SETEXTATTR(vp, attrnamespace, attrname, NULL, NULL); 845 846 if ((ioflg & IO_NODELOCKED) == 0) { 847 VOP_UNLOCK(vp, 0); 848 } 849 850 return (error); 851 } 852 853 void 854 vn_ra_allocctx(struct vnode *vp) 855 { 856 struct uvm_ractx *ra = NULL; 857 858 KASSERT(mutex_owned(&vp->v_interlock)); 859 860 if (vp->v_type != VREG) { 861 return; 862 } 863 if (vp->v_ractx != NULL) { 864 return; 865 } 866 if (vp->v_ractx == NULL) { 867 mutex_exit(&vp->v_interlock); 868 ra = uvm_ra_allocctx(); 869 mutex_enter(&vp->v_interlock); 870 if (ra != NULL && vp->v_ractx == NULL) { 871 vp->v_ractx = ra; 872 ra = NULL; 873 } 874 } 875 if (ra != NULL) { 876 uvm_ra_freectx(ra); 877 } 878 } 879
Indexes created Sun Sep 21 20:09:37 GMT 2025