vfs_vnops.c revision 1.160
1 /* $NetBSD: vfs_vnops.c,v 1.160 2008/08/27 06:28:09 christos 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 1.160 2008/08/27 06:28:09 christos 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 #include <sys/wapbl.h> 65 66 #include <miscfs/specfs/specdev.h> 67 68 #include <uvm/uvm_extern.h> 69 #include <uvm/uvm_readahead.h> 70 71 #ifdef UNION 72 #include <fs/union/union.h> 73 #endif 74 75 #if defined(LKM) || defined(UNION) 76 int (*vn_union_readdir_hook) (struct vnode **, struct file *, struct lwp *); 77 #endif 78 79 #include <sys/verified_exec.h> 80 81 static int vn_read(file_t *fp, off_t *offset, struct uio *uio, 82 kauth_cred_t cred, int flags); 83 static int vn_write(file_t *fp, off_t *offset, struct uio *uio, 84 kauth_cred_t cred, int flags); 85 static int vn_closefile(file_t *fp); 86 static int vn_poll(file_t *fp, int events); 87 static int vn_fcntl(file_t *fp, u_int com, void *data); 88 static int vn_statfile(file_t *fp, struct stat *sb); 89 static int vn_ioctl(file_t *fp, u_long com, void *data); 90 91 const struct fileops vnops = { 92 vn_read, vn_write, vn_ioctl, vn_fcntl, vn_poll, 93 vn_statfile, vn_closefile, vn_kqfilter 94 }; 95 96 /* 97 * Common code for vnode open operations. 98 * Check permissions, and call the VOP_OPEN or VOP_CREATE routine. 99 */ 100 int 101 vn_open(struct nameidata *ndp, int fmode, int cmode) 102 { 103 struct vnode *vp; 104 struct lwp *l = curlwp; 105 kauth_cred_t cred = l->l_cred; 106 struct vattr va; 107 int error; 108 char *path; 109 110 ndp->ni_cnd.cn_flags &= TRYEMULROOT; 111 112 if (fmode & O_CREAT) { 113 ndp->ni_cnd.cn_nameiop = CREATE; 114 ndp->ni_cnd.cn_flags |= LOCKPARENT | LOCKLEAF; 115 if ((fmode & O_EXCL) == 0 && 116 ((fmode & O_NOFOLLOW) == 0)) 117 ndp->ni_cnd.cn_flags |= FOLLOW; 118 } else { 119 ndp->ni_cnd.cn_nameiop = LOOKUP; 120 ndp->ni_cnd.cn_flags |= LOCKLEAF; 121 if ((fmode & O_NOFOLLOW) == 0) 122 ndp->ni_cnd.cn_flags |= FOLLOW; 123 } 124 125 VERIEXEC_PATH_GET(ndp->ni_dirp, ndp->ni_segflg, ndp->ni_dirp, path); 126 127 error = namei(ndp); 128 if (error) 129 goto out; 130 131 vp = ndp->ni_vp; 132 133 #if NVERIEXEC > 0 134 error = veriexec_openchk(l, ndp->ni_vp, ndp->ni_dirp, fmode); 135 if (error) 136 goto bad; 137 #endif /* NVERIEXEC > 0 */ 138 139 if (fmode & O_CREAT) { 140 if (ndp->ni_vp == NULL) { 141 VATTR_NULL(&va); 142 va.va_type = VREG; 143 va.va_mode = cmode; 144 if (fmode & O_EXCL) 145 va.va_vaflags |= VA_EXCLUSIVE; 146 error = VOP_CREATE(ndp->ni_dvp, &ndp->ni_vp, 147 &ndp->ni_cnd, &va); 148 if (error) 149 goto out; 150 fmode &= ~O_TRUNC; 151 vp = ndp->ni_vp; 152 } else { 153 VOP_ABORTOP(ndp->ni_dvp, &ndp->ni_cnd); 154 if (ndp->ni_dvp == ndp->ni_vp) 155 vrele(ndp->ni_dvp); 156 else 157 vput(ndp->ni_dvp); 158 ndp->ni_dvp = NULL; 159 vp = ndp->ni_vp; 160 if (fmode & O_EXCL) { 161 error = EEXIST; 162 goto bad; 163 } 164 fmode &= ~O_CREAT; 165 } 166 } else { 167 vp = ndp->ni_vp; 168 } 169 if (vp->v_type == VSOCK) { 170 error = EOPNOTSUPP; 171 goto bad; 172 } 173 if (ndp->ni_vp->v_type == VLNK) { 174 error = EFTYPE; 175 goto bad; 176 } 177 178 if ((fmode & O_CREAT) == 0) { 179 error = vn_openchk(vp, cred, fmode); 180 if (error != 0) 181 goto bad; 182 } 183 184 if (fmode & O_TRUNC) { 185 VOP_UNLOCK(vp, 0); /* XXX */ 186 187 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); /* XXX */ 188 VATTR_NULL(&va); 189 va.va_size = 0; 190 error = VOP_SETATTR(vp, &va, cred); 191 if (error != 0) 192 goto bad; 193 } 194 if ((error = VOP_OPEN(vp, fmode, cred)) != 0) 195 goto bad; 196 if (fmode & FWRITE) { 197 mutex_enter(&vp->v_interlock); 198 vp->v_writecount++; 199 mutex_exit(&vp->v_interlock); 200 } 201 202 bad: 203 if (error) 204 vput(vp); 205 out: 206 VERIEXEC_PATH_PUT(path); 207 return (error); 208 } 209 210 /* 211 * Check for write permissions on the specified vnode. 212 * Prototype text segments cannot be written. 213 */ 214 int 215 vn_writechk(struct vnode *vp) 216 { 217 218 /* 219 * If the vnode is in use as a process's text, 220 * we can't allow writing. 221 */ 222 if (vp->v_iflag & VI_TEXT) 223 return (ETXTBSY); 224 return (0); 225 } 226 227 int 228 vn_openchk(struct vnode *vp, kauth_cred_t cred, int fflags) 229 { 230 int permbits = 0; 231 int error; 232 233 if ((fflags & FREAD) != 0) { 234 permbits = VREAD; 235 } 236 if ((fflags & (FWRITE | O_TRUNC)) != 0) { 237 permbits |= VWRITE; 238 if (vp->v_type == VDIR) { 239 error = EISDIR; 240 goto bad; 241 } 242 error = vn_writechk(vp); 243 if (error != 0) 244 goto bad; 245 } 246 error = VOP_ACCESS(vp, permbits, cred); 247 bad: 248 return error; 249 } 250 251 /* 252 * Mark a vnode as having executable mappings. 253 */ 254 void 255 vn_markexec(struct vnode *vp) 256 { 257 258 if ((vp->v_iflag & VI_EXECMAP) != 0) { 259 /* Safe unlocked, as long as caller holds a reference. */ 260 return; 261 } 262 263 mutex_enter(&vp->v_interlock); 264 if ((vp->v_iflag & VI_EXECMAP) == 0) { 265 atomic_add_int(&uvmexp.filepages, -vp->v_uobj.uo_npages); 266 atomic_add_int(&uvmexp.execpages, vp->v_uobj.uo_npages); 267 vp->v_iflag |= VI_EXECMAP; 268 } 269 mutex_exit(&vp->v_interlock); 270 } 271 272 /* 273 * Mark a vnode as being the text of a process. 274 * Fail if the vnode is currently writable. 275 */ 276 int 277 vn_marktext(struct vnode *vp) 278 { 279 280 if ((vp->v_iflag & (VI_TEXT|VI_EXECMAP)) == (VI_TEXT|VI_EXECMAP)) { 281 /* Safe unlocked, as long as caller holds a reference. */ 282 return (0); 283 } 284 285 mutex_enter(&vp->v_interlock); 286 if (vp->v_writecount != 0) { 287 KASSERT((vp->v_iflag & VI_TEXT) == 0); 288 mutex_exit(&vp->v_interlock); 289 return (ETXTBSY); 290 } 291 if ((vp->v_iflag & VI_EXECMAP) == 0) { 292 atomic_add_int(&uvmexp.filepages, -vp->v_uobj.uo_npages); 293 atomic_add_int(&uvmexp.execpages, vp->v_uobj.uo_npages); 294 } 295 vp->v_iflag |= (VI_TEXT | VI_EXECMAP); 296 mutex_exit(&vp->v_interlock); 297 return (0); 298 } 299 300 /* 301 * Vnode close call 302 * 303 * Note: takes an unlocked vnode, while VOP_CLOSE takes a locked node. 304 */ 305 int 306 vn_close(struct vnode *vp, int flags, kauth_cred_t cred) 307 { 308 int error; 309 310 if (flags & FWRITE) { 311 mutex_enter(&vp->v_interlock); 312 vp->v_writecount--; 313 mutex_exit(&vp->v_interlock); 314 } 315 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 316 error = VOP_CLOSE(vp, flags, cred); 317 vput(vp); 318 return (error); 319 } 320 321 /* 322 * Package up an I/O request on a vnode into a uio and do it. 323 */ 324 int 325 vn_rdwr(enum uio_rw rw, struct vnode *vp, void *base, int len, off_t offset, 326 enum uio_seg segflg, int ioflg, kauth_cred_t cred, size_t *aresid, 327 struct lwp *l) 328 { 329 struct uio auio; 330 struct iovec aiov; 331 int error; 332 333 if ((ioflg & IO_NODELOCKED) == 0) { 334 if (rw == UIO_READ) { 335 vn_lock(vp, LK_SHARED | LK_RETRY); 336 } else /* UIO_WRITE */ { 337 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 338 } 339 } 340 auio.uio_iov = &aiov; 341 auio.uio_iovcnt = 1; 342 aiov.iov_base = base; 343 aiov.iov_len = len; 344 auio.uio_resid = len; 345 auio.uio_offset = offset; 346 auio.uio_rw = rw; 347 if (segflg == UIO_SYSSPACE) { 348 UIO_SETUP_SYSSPACE(&auio); 349 } else { 350 auio.uio_vmspace = l->l_proc->p_vmspace; 351 } 352 if (rw == UIO_READ) { 353 error = VOP_READ(vp, &auio, ioflg, cred); 354 } else { 355 error = VOP_WRITE(vp, &auio, ioflg, cred); 356 } 357 if (aresid) 358 *aresid = auio.uio_resid; 359 else 360 if (auio.uio_resid && error == 0) 361 error = EIO; 362 if ((ioflg & IO_NODELOCKED) == 0) { 363 VOP_UNLOCK(vp, 0); 364 } 365 return (error); 366 } 367 368 int 369 vn_readdir(file_t *fp, char *bf, int segflg, u_int count, int *done, 370 struct lwp *l, off_t **cookies, int *ncookies) 371 { 372 struct vnode *vp = (struct vnode *)fp->f_data; 373 struct iovec aiov; 374 struct uio auio; 375 int error, eofflag; 376 377 /* Limit the size on any kernel buffers used by VOP_READDIR */ 378 count = min(MAXBSIZE, count); 379 380 unionread: 381 if (vp->v_type != VDIR) 382 return (EINVAL); 383 aiov.iov_base = bf; 384 aiov.iov_len = count; 385 auio.uio_iov = &aiov; 386 auio.uio_iovcnt = 1; 387 auio.uio_rw = UIO_READ; 388 if (segflg == UIO_SYSSPACE) { 389 UIO_SETUP_SYSSPACE(&auio); 390 } else { 391 KASSERT(l == curlwp); 392 auio.uio_vmspace = l->l_proc->p_vmspace; 393 } 394 auio.uio_resid = count; 395 vn_lock(vp, LK_SHARED | LK_RETRY); 396 auio.uio_offset = fp->f_offset; 397 error = VOP_READDIR(vp, &auio, fp->f_cred, &eofflag, cookies, 398 ncookies); 399 FILE_LOCK(fp); 400 fp->f_offset = auio.uio_offset; 401 FILE_UNLOCK(fp); 402 VOP_UNLOCK(vp, 0); 403 if (error) 404 return (error); 405 406 #if defined(UNION) || defined(LKM) 407 if (count == auio.uio_resid && vn_union_readdir_hook) { 408 struct vnode *ovp = vp; 409 410 error = (*vn_union_readdir_hook)(&vp, fp, l); 411 if (error) 412 return (error); 413 if (vp != ovp) 414 goto unionread; 415 } 416 #endif /* UNION || LKM */ 417 418 if (count == auio.uio_resid && (vp->v_vflag & VV_ROOT) && 419 (vp->v_mount->mnt_flag & MNT_UNION)) { 420 struct vnode *tvp = vp; 421 vp = vp->v_mount->mnt_vnodecovered; 422 VREF(vp); 423 FILE_LOCK(fp); 424 fp->f_data = vp; 425 fp->f_offset = 0; 426 FILE_UNLOCK(fp); 427 vrele(tvp); 428 goto unionread; 429 } 430 *done = count - auio.uio_resid; 431 return error; 432 } 433 434 /* 435 * File table vnode read routine. 436 */ 437 static int 438 vn_read(file_t *fp, off_t *offset, struct uio *uio, kauth_cred_t cred, 439 int flags) 440 { 441 struct vnode *vp = (struct vnode *)fp->f_data; 442 int count, error, ioflag, fflag; 443 444 ioflag = IO_ADV_ENCODE(fp->f_advice); 445 fflag = fp->f_flag; 446 if (fflag & FNONBLOCK) 447 ioflag |= IO_NDELAY; 448 if ((fflag & (FFSYNC | FRSYNC)) == (FFSYNC | FRSYNC)) 449 ioflag |= IO_SYNC; 450 if (fflag & FALTIO) 451 ioflag |= IO_ALTSEMANTICS; 452 if (fflag & FDIRECT) 453 ioflag |= IO_DIRECT; 454 vn_lock(vp, LK_SHARED | LK_RETRY); 455 uio->uio_offset = *offset; 456 count = uio->uio_resid; 457 error = VOP_READ(vp, uio, ioflag, cred); 458 if (flags & FOF_UPDATE_OFFSET) 459 *offset += count - uio->uio_resid; 460 VOP_UNLOCK(vp, 0); 461 return (error); 462 } 463 464 /* 465 * File table vnode write routine. 466 */ 467 static int 468 vn_write(file_t *fp, off_t *offset, struct uio *uio, kauth_cred_t cred, 469 int flags) 470 { 471 struct vnode *vp = (struct vnode *)fp->f_data; 472 int count, error, ioflag, fflag; 473 474 ioflag = IO_ADV_ENCODE(fp->f_advice) | IO_UNIT; 475 fflag = fp->f_flag; 476 if (vp->v_type == VREG && (fflag & O_APPEND)) 477 ioflag |= IO_APPEND; 478 if (fflag & FNONBLOCK) 479 ioflag |= IO_NDELAY; 480 if (fflag & FFSYNC || 481 (vp->v_mount && (vp->v_mount->mnt_flag & MNT_SYNCHRONOUS))) 482 ioflag |= IO_SYNC; 483 else if (fflag & FDSYNC) 484 ioflag |= IO_DSYNC; 485 if (fflag & FALTIO) 486 ioflag |= IO_ALTSEMANTICS; 487 if (fflag & FDIRECT) 488 ioflag |= IO_DIRECT; 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 /* 496 * SUSv3 describes behaviour for count = 0 as following: 497 * "Before any action ... is taken, and if nbyte is zero 498 * and the file is a regular file, the write() function 499 * ... in the absence of errors ... shall return zero 500 * and have no other results." 501 */ 502 if (count) 503 *offset = uio->uio_offset; 504 } else 505 *offset += count - uio->uio_resid; 506 } 507 VOP_UNLOCK(vp, 0); 508 return (error); 509 } 510 511 /* 512 * File table vnode stat routine. 513 */ 514 static int 515 vn_statfile(file_t *fp, struct stat *sb) 516 { 517 struct vnode *vp = (struct vnode *)fp->f_data; 518 519 return vn_stat(vp, sb); 520 } 521 522 int 523 vn_stat(struct vnode *vp, struct stat *sb) 524 { 525 struct vattr va; 526 int error; 527 mode_t mode; 528 529 error = VOP_GETATTR(vp, &va, kauth_cred_get()); 530 if (error) 531 return (error); 532 /* 533 * Copy from vattr table 534 */ 535 sb->st_dev = va.va_fsid; 536 sb->st_ino = va.va_fileid; 537 mode = va.va_mode; 538 switch (vp->v_type) { 539 case VREG: 540 mode |= S_IFREG; 541 break; 542 case VDIR: 543 mode |= S_IFDIR; 544 break; 545 case VBLK: 546 mode |= S_IFBLK; 547 break; 548 case VCHR: 549 mode |= S_IFCHR; 550 break; 551 case VLNK: 552 mode |= S_IFLNK; 553 break; 554 case VSOCK: 555 mode |= S_IFSOCK; 556 break; 557 case VFIFO: 558 mode |= S_IFIFO; 559 break; 560 default: 561 return (EBADF); 562 }; 563 sb->st_mode = mode; 564 sb->st_nlink = va.va_nlink; 565 sb->st_uid = va.va_uid; 566 sb->st_gid = va.va_gid; 567 sb->st_rdev = va.va_rdev; 568 sb->st_size = va.va_size; 569 sb->st_atimespec = va.va_atime; 570 sb->st_mtimespec = va.va_mtime; 571 sb->st_ctimespec = va.va_ctime; 572 sb->st_birthtimespec = va.va_birthtime; 573 sb->st_blksize = va.va_blocksize; 574 sb->st_flags = va.va_flags; 575 sb->st_gen = 0; 576 sb->st_blocks = va.va_bytes / S_BLKSIZE; 577 return (0); 578 } 579 580 /* 581 * File table vnode fcntl routine. 582 */ 583 static int 584 vn_fcntl(file_t *fp, u_int com, void *data) 585 { 586 struct vnode *vp = fp->f_data; 587 int error; 588 589 error = VOP_FCNTL(vp, com, data, fp->f_flag, kauth_cred_get()); 590 return (error); 591 } 592 593 /* 594 * File table vnode ioctl routine. 595 */ 596 static int 597 vn_ioctl(file_t *fp, u_long com, void *data) 598 { 599 struct vnode *vp = fp->f_data, *ovp; 600 struct vattr vattr; 601 int error; 602 603 switch (vp->v_type) { 604 605 case VREG: 606 case VDIR: 607 if (com == FIONREAD) { 608 error = VOP_GETATTR(vp, &vattr, 609 kauth_cred_get()); 610 if (error) 611 return (error); 612 *(int *)data = vattr.va_size - fp->f_offset; 613 return (0); 614 } 615 if ((com == FIONWRITE) || (com == FIONSPACE)) { 616 /* 617 * Files don't have send queues, so there never 618 * are any bytes in them, nor is there any 619 * open space in them. 620 */ 621 *(int *)data = 0; 622 return (0); 623 } 624 if (com == FIOGETBMAP) { 625 daddr_t *block; 626 627 if (*(daddr_t *)data < 0) 628 return (EINVAL); 629 block = (daddr_t *)data; 630 return (VOP_BMAP(vp, *block, NULL, block, NULL)); 631 } 632 if (com == OFIOGETBMAP) { 633 daddr_t ibn, obn; 634 635 if (*(int32_t *)data < 0) 636 return (EINVAL); 637 ibn = (daddr_t)*(int32_t *)data; 638 error = VOP_BMAP(vp, ibn, NULL, &obn, NULL); 639 *(int32_t *)data = (int32_t)obn; 640 return error; 641 } 642 if (com == FIONBIO || com == FIOASYNC) /* XXX */ 643 return (0); /* XXX */ 644 /* fall into ... */ 645 case VFIFO: 646 case VCHR: 647 case VBLK: 648 error = VOP_IOCTL(vp, com, data, fp->f_flag, 649 kauth_cred_get()); 650 if (error == 0 && com == TIOCSCTTY) { 651 VREF(vp); 652 mutex_enter(proc_lock); 653 ovp = curproc->p_session->s_ttyvp; 654 curproc->p_session->s_ttyvp = vp; 655 mutex_exit(proc_lock); 656 if (ovp != NULL) 657 vrele(ovp); 658 } 659 return (error); 660 661 default: 662 return (EPASSTHROUGH); 663 } 664 } 665 666 /* 667 * File table vnode poll routine. 668 */ 669 static int 670 vn_poll(file_t *fp, int events) 671 { 672 673 return (VOP_POLL(fp->f_data, events)); 674 } 675 676 /* 677 * File table vnode kqfilter routine. 678 */ 679 int 680 vn_kqfilter(file_t *fp, struct knote *kn) 681 { 682 683 return (VOP_KQFILTER(fp->f_data, kn)); 684 } 685 686 /* 687 * Check that the vnode is still valid, and if so 688 * acquire requested lock. 689 */ 690 int 691 vn_lock(struct vnode *vp, int flags) 692 { 693 int error; 694 695 #if 0 696 KASSERT(vp->v_usecount > 0 || (flags & LK_INTERLOCK) != 0 697 || (vp->v_iflag & VI_ONWORKLST) != 0); 698 #endif 699 KASSERT((flags & 700 ~(LK_INTERLOCK|LK_SHARED|LK_EXCLUSIVE|LK_NOWAIT|LK_RETRY| 701 LK_CANRECURSE)) 702 == 0); 703 704 #ifdef DIAGNOSTIC 705 if (wapbl_vphaswapbl(vp)) 706 WAPBL_JUNLOCK_ASSERT(wapbl_vptomp(vp)); 707 #endif 708 709 do { 710 /* 711 * XXX PR 37706 forced unmount of file systems is unsafe. 712 * Race between vclean() and this the remaining problem. 713 */ 714 if (vp->v_iflag & VI_XLOCK) { 715 if ((flags & LK_INTERLOCK) == 0) { 716 mutex_enter(&vp->v_interlock); 717 } 718 flags &= ~LK_INTERLOCK; 719 if (flags & LK_NOWAIT) { 720 mutex_exit(&vp->v_interlock); 721 return EBUSY; 722 } 723 vwait(vp, VI_XLOCK); 724 mutex_exit(&vp->v_interlock); 725 error = ENOENT; 726 } else { 727 if ((flags & LK_INTERLOCK) != 0) { 728 mutex_exit(&vp->v_interlock); 729 } 730 flags &= ~LK_INTERLOCK; 731 error = VOP_LOCK(vp, (flags & ~LK_RETRY)); 732 if (error == 0 || error == EDEADLK || error == EBUSY) 733 return (error); 734 } 735 } while (flags & LK_RETRY); 736 return (error); 737 } 738 739 /* 740 * File table vnode close routine. 741 */ 742 static int 743 vn_closefile(file_t *fp) 744 { 745 746 return vn_close(fp->f_data, fp->f_flag, fp->f_cred); 747 } 748 749 /* 750 * Enable LK_CANRECURSE on lock. Return prior status. 751 */ 752 u_int 753 vn_setrecurse(struct vnode *vp) 754 { 755 struct vnlock *lkp; 756 757 lkp = (vp->v_vnlock != NULL ? vp->v_vnlock : &vp->v_lock); 758 atomic_inc_uint(&lkp->vl_canrecurse); 759 760 return 0; 761 } 762 763 /* 764 * Called when done with locksetrecurse. 765 */ 766 void 767 vn_restorerecurse(struct vnode *vp, u_int flags) 768 { 769 struct vnlock *lkp; 770 771 lkp = (vp->v_vnlock != NULL ? vp->v_vnlock : &vp->v_lock); 772 atomic_dec_uint(&lkp->vl_canrecurse); 773 } 774 775 /* 776 * Simplified in-kernel wrapper calls for extended attribute access. 777 * Both calls pass in a NULL credential, authorizing a "kernel" access. 778 * Set IO_NODELOCKED in ioflg if the vnode is already locked. 779 */ 780 int 781 vn_extattr_get(struct vnode *vp, int ioflg, int attrnamespace, 782 const char *attrname, size_t *buflen, void *bf, struct lwp *l) 783 { 784 struct uio auio; 785 struct iovec aiov; 786 int error; 787 788 aiov.iov_len = *buflen; 789 aiov.iov_base = bf; 790 791 auio.uio_iov = &aiov; 792 auio.uio_iovcnt = 1; 793 auio.uio_rw = UIO_READ; 794 auio.uio_offset = 0; 795 auio.uio_resid = *buflen; 796 UIO_SETUP_SYSSPACE(&auio); 797 798 if ((ioflg & IO_NODELOCKED) == 0) 799 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 800 801 error = VOP_GETEXTATTR(vp, attrnamespace, attrname, &auio, NULL, NULL); 802 803 if ((ioflg & IO_NODELOCKED) == 0) 804 VOP_UNLOCK(vp, 0); 805 806 if (error == 0) 807 *buflen = *buflen - auio.uio_resid; 808 809 return (error); 810 } 811 812 /* 813 * XXX Failure mode if partially written? 814 */ 815 int 816 vn_extattr_set(struct vnode *vp, int ioflg, int attrnamespace, 817 const char *attrname, size_t buflen, const void *bf, struct lwp *l) 818 { 819 struct uio auio; 820 struct iovec aiov; 821 int error; 822 823 aiov.iov_len = buflen; 824 aiov.iov_base = __UNCONST(bf); /* XXXUNCONST kills const */ 825 826 auio.uio_iov = &aiov; 827 auio.uio_iovcnt = 1; 828 auio.uio_rw = UIO_WRITE; 829 auio.uio_offset = 0; 830 auio.uio_resid = buflen; 831 UIO_SETUP_SYSSPACE(&auio); 832 833 if ((ioflg & IO_NODELOCKED) == 0) { 834 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 835 } 836 837 error = VOP_SETEXTATTR(vp, attrnamespace, attrname, &auio, NULL); 838 839 if ((ioflg & IO_NODELOCKED) == 0) { 840 VOP_UNLOCK(vp, 0); 841 } 842 843 return (error); 844 } 845 846 int 847 vn_extattr_rm(struct vnode *vp, int ioflg, int attrnamespace, 848 const char *attrname, struct lwp *l) 849 { 850 int error; 851 852 if ((ioflg & IO_NODELOCKED) == 0) { 853 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 854 } 855 856 error = VOP_DELETEEXTATTR(vp, attrnamespace, attrname, NULL); 857 if (error == EOPNOTSUPP) 858 error = VOP_SETEXTATTR(vp, attrnamespace, attrname, NULL, NULL); 859 860 if ((ioflg & IO_NODELOCKED) == 0) { 861 VOP_UNLOCK(vp, 0); 862 } 863 864 return (error); 865 } 866 867 void 868 vn_ra_allocctx(struct vnode *vp) 869 { 870 struct uvm_ractx *ra = NULL; 871 872 KASSERT(mutex_owned(&vp->v_interlock)); 873 874 if (vp->v_type != VREG) { 875 return; 876 } 877 if (vp->v_ractx != NULL) { 878 return; 879 } 880 if (vp->v_ractx == NULL) { 881 mutex_exit(&vp->v_interlock); 882 ra = uvm_ra_allocctx(); 883 mutex_enter(&vp->v_interlock); 884 if (ra != NULL && vp->v_ractx == NULL) { 885 vp->v_ractx = ra; 886 ra = NULL; 887 } 888 } 889 if (ra != NULL) { 890 uvm_ra_freectx(ra); 891 } 892 } 893
Indexes created Sat Sep 20 22:09:52 GMT 2025