vfs_vnops.c revision 1.135
1/* $NetBSD: vfs_vnops.c,v 1.135 2007/03/09 14:11:27 ad 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 1.135 2007/03/09 14:11:27 ad 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 62#include <miscfs/specfs/specdev.h> 63 64#include <uvm/uvm_extern.h> 65#include <uvm/uvm_readahead.h> 66 67#ifdef UNION 68#include <fs/union/union.h> 69#endif 70 71#if defined(LKM) || defined(UNION) 72int (*vn_union_readdir_hook) (struct vnode **, struct file *, struct lwp *); 73#endif 74 75#if NVERIEXEC > 0 76#include <sys/verified_exec.h> 77#endif /* NVERIEXEC > 0 */ 78 79static int vn_read(struct file *fp, off_t *offset, struct uio *uio, 80 kauth_cred_t cred, int flags); 81static int vn_write(struct file *fp, off_t *offset, struct uio *uio, 82 kauth_cred_t cred, int flags); 83static int vn_closefile(struct file *fp, struct lwp *l); 84static int vn_poll(struct file *fp, int events, struct lwp *l); 85static int vn_fcntl(struct file *fp, u_int com, void *data, struct lwp *l); 86static int vn_statfile(struct file *fp, struct stat *sb, struct lwp *l); 87static int vn_ioctl(struct file *fp, u_long com, void *data, struct lwp *l); 88 89const struct fileops vnops = { 90 vn_read, vn_write, vn_ioctl, vn_fcntl, vn_poll, 91 vn_statfile, vn_closefile, vn_kqfilter 92}; 93 94/* 95 * Common code for vnode open operations. 96 * Check permissions, and call the VOP_OPEN or VOP_CREATE routine. 97 */ 98int 99vn_open(struct nameidata *ndp, int fmode, int cmode) 100{ 101 struct vnode *vp; 102 struct mount *mp = NULL; /* XXX: GCC */ 103 struct lwp *l = ndp->ni_cnd.cn_lwp; 104 kauth_cred_t cred = l->l_cred; 105 struct vattr va; 106 int error; 107 pathname_t pn = NULL; 108 109restart: 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 } else { 117 ndp->ni_cnd.cn_nameiop = LOOKUP; 118 ndp->ni_cnd.cn_flags = LOCKLEAF; 119 if ((fmode & O_NOFOLLOW) == 0) 120 ndp->ni_cnd.cn_flags |= FOLLOW; 121 } 122#if NVERIEXEC > 0 123 error = pathname_get(ndp->ni_dirp, ndp->ni_segflg, &pn); 124 if (error) 125 goto bad2; 126 ndp->ni_dirp = pathname_path(pn); 127 ndp->ni_segflg = UIO_SYSSPACE; 128#endif /* NVERIEXEC > 0 */ 129 error = namei(ndp); 130 if (error) 131 goto bad2; 132 133 vp = ndp->ni_vp; 134 135#if NVERIEXEC > 0 136 error = veriexec_openchk(l, ndp->ni_vp, ndp->ni_dirp, fmode); 137 if (error) 138 goto bad; 139#endif /* NVERIEXEC > 0 */ 140 141 if (fmode & O_CREAT) { 142 if (ndp->ni_vp == NULL) { 143 VATTR_NULL(&va); 144 va.va_type = VREG; 145 va.va_mode = cmode; 146 if (fmode & O_EXCL) 147 va.va_vaflags |= VA_EXCLUSIVE; 148 if (vn_start_write(ndp->ni_dvp, &mp, V_NOWAIT) != 0) { 149 VOP_ABORTOP(ndp->ni_dvp, &ndp->ni_cnd); 150 vput(ndp->ni_dvp); 151 if ((error = vn_start_write(NULL, &mp, 152 V_WAIT | V_SLEEPONLY | V_PCATCH)) != 0) 153 goto bad2; 154 goto restart; 155 } 156 VOP_LEASE(ndp->ni_dvp, l, cred, LEASE_WRITE); 157 error = VOP_CREATE(ndp->ni_dvp, &ndp->ni_vp, 158 &ndp->ni_cnd, &va); 159 vn_finished_write(mp, 0); 160 if (error) 161 goto bad2; 162 fmode &= ~O_TRUNC; 163 vp = ndp->ni_vp; 164 } else { 165 VOP_ABORTOP(ndp->ni_dvp, &ndp->ni_cnd); 166 if (ndp->ni_dvp == ndp->ni_vp) 167 vrele(ndp->ni_dvp); 168 else 169 vput(ndp->ni_dvp); 170 ndp->ni_dvp = NULL; 171 vp = ndp->ni_vp; 172 if (fmode & O_EXCL) { 173 error = EEXIST; 174 goto bad; 175 } 176 fmode &= ~O_CREAT; 177 } 178 } else { 179 vp = ndp->ni_vp; 180 } 181 if (vp->v_type == VSOCK) { 182 error = EOPNOTSUPP; 183 goto bad; 184 } 185 if (ndp->ni_vp->v_type == VLNK) { 186 error = EFTYPE; 187 goto bad; 188 } 189 190 if ((fmode & O_CREAT) == 0) { 191 if (fmode & FREAD) { 192 if ((error = VOP_ACCESS(vp, VREAD, cred, l)) != 0) 193 goto bad; 194 } 195 196 if (fmode & (FWRITE | O_TRUNC)) { 197 if (vp->v_type == VDIR) { 198 error = EISDIR; 199 goto bad; 200 } 201 if ((error = vn_writechk(vp)) != 0 || 202 (error = VOP_ACCESS(vp, VWRITE, cred, l)) != 0) 203 goto bad; 204 } 205 } 206 207 if (fmode & O_TRUNC) { 208 VOP_UNLOCK(vp, 0); /* XXX */ 209 210 if ((error = vn_start_write(vp, &mp, V_WAIT | V_PCATCH)) != 0) { 211 vrele(vp); 212 goto bad2; 213 } 214 VOP_LEASE(vp, l, cred, LEASE_WRITE); 215 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); /* XXX */ 216 VATTR_NULL(&va); 217 va.va_size = 0; 218 error = VOP_SETATTR(vp, &va, cred, l); 219 vn_finished_write(mp, 0); 220 if (error != 0) 221 goto bad; 222 } 223 if ((error = VOP_OPEN(vp, fmode, cred, l)) != 0) 224 goto bad; 225 if (vp->v_type == VREG && 226 uvn_attach(vp, fmode & FWRITE ? VM_PROT_WRITE : 0) == NULL) { 227 error = EIO; 228 goto bad; 229 } 230 if (fmode & FWRITE) 231 vp->v_writecount++; 232 233bad: 234 if (error) 235 vput(vp); 236 237bad2: 238 pathname_put(pn); 239 240 return (error); 241} 242 243/* 244 * Check for write permissions on the specified vnode. 245 * Prototype text segments cannot be written. 246 */ 247int 248vn_writechk(struct vnode *vp) 249{ 250 251 /* 252 * If the vnode is in use as a process's text, 253 * we can't allow writing. 254 */ 255 if (vp->v_flag & VTEXT) 256 return (ETXTBSY); 257 return (0); 258} 259 260/* 261 * Mark a vnode as having executable mappings. 262 */ 263void 264vn_markexec(struct vnode *vp) 265{ 266 if ((vp->v_flag & VEXECMAP) == 0) { 267 uvmexp.filepages -= vp->v_uobj.uo_npages; 268 uvmexp.execpages += vp->v_uobj.uo_npages; 269 } 270 vp->v_flag |= VEXECMAP; 271} 272 273/* 274 * Mark a vnode as being the text of a process. 275 * Fail if the vnode is currently writable. 276 */ 277int 278vn_marktext(struct vnode *vp) 279{ 280 281 if (vp->v_writecount != 0) { 282 KASSERT((vp->v_flag & VTEXT) == 0); 283 return (ETXTBSY); 284 } 285 vp->v_flag |= VTEXT; 286 vn_markexec(vp); 287 return (0); 288} 289 290/* 291 * Vnode close call 292 * 293 * Note: takes an unlocked vnode, while VOP_CLOSE takes a locked node. 294 */ 295int 296vn_close(struct vnode *vp, int flags, kauth_cred_t cred, struct lwp *l) 297{ 298 int error; 299 300 if (flags & FWRITE) 301 vp->v_writecount--; 302 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 303 error = VOP_CLOSE(vp, flags, cred, l); 304 vput(vp); 305 return (error); 306} 307 308/* 309 * Package up an I/O request on a vnode into a uio and do it. 310 */ 311int 312vn_rdwr(enum uio_rw rw, struct vnode *vp, void *base, int len, off_t offset, 313 enum uio_seg segflg, int ioflg, kauth_cred_t cred, size_t *aresid, 314 struct lwp *l) 315{ 316 struct uio auio; 317 struct iovec aiov; 318 struct mount *mp = NULL; 319 int error; 320 321 if ((ioflg & IO_NODELOCKED) == 0) { 322 if (rw == UIO_READ) { 323 vn_lock(vp, LK_SHARED | LK_RETRY); 324 } else /* UIO_WRITE */ { 325 if (vp->v_type != VCHR && 326 (error = vn_start_write(vp, &mp, V_WAIT | V_PCATCH)) 327 != 0) 328 return (error); 329 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 330 } 331 } 332 auio.uio_iov = &aiov; 333 auio.uio_iovcnt = 1; 334 aiov.iov_base = base; 335 aiov.iov_len = len; 336 auio.uio_resid = len; 337 auio.uio_offset = offset; 338 auio.uio_rw = rw; 339 if (segflg == UIO_SYSSPACE) { 340 UIO_SETUP_SYSSPACE(&auio); 341 } else { 342 auio.uio_vmspace = l->l_proc->p_vmspace; 343 } 344 if (rw == UIO_READ) { 345 error = VOP_READ(vp, &auio, ioflg, cred); 346 } else { 347 error = VOP_WRITE(vp, &auio, ioflg, cred); 348 } 349 if (aresid) 350 *aresid = auio.uio_resid; 351 else 352 if (auio.uio_resid && error == 0) 353 error = EIO; 354 if ((ioflg & IO_NODELOCKED) == 0) { 355 if (rw == UIO_WRITE) 356 vn_finished_write(mp, 0); 357 VOP_UNLOCK(vp, 0); 358 } 359 return (error); 360} 361 362int 363vn_readdir(struct file *fp, char *bf, int segflg, u_int count, int *done, 364 struct lwp *l, off_t **cookies, int *ncookies) 365{ 366 struct vnode *vp = (struct vnode *)fp->f_data; 367 struct iovec aiov; 368 struct uio auio; 369 int error, eofflag; 370 371 /* Limit the size on any kernel buffers used by VOP_READDIR */ 372 count = min(MAXBSIZE, count); 373 374unionread: 375 if (vp->v_type != VDIR) 376 return (EINVAL); 377 aiov.iov_base = bf; 378 aiov.iov_len = count; 379 auio.uio_iov = &aiov; 380 auio.uio_iovcnt = 1; 381 auio.uio_rw = UIO_READ; 382 if (segflg == UIO_SYSSPACE) { 383 UIO_SETUP_SYSSPACE(&auio); 384 } else { 385 KASSERT(l == curlwp); 386 auio.uio_vmspace = l->l_proc->p_vmspace; 387 } 388 auio.uio_resid = count; 389 vn_lock(vp, LK_SHARED | LK_RETRY); 390 auio.uio_offset = fp->f_offset; 391 error = VOP_READDIR(vp, &auio, fp->f_cred, &eofflag, cookies, 392 ncookies); 393 fp->f_offset = auio.uio_offset; 394 VOP_UNLOCK(vp, 0); 395 if (error) 396 return (error); 397 398#if defined(UNION) || defined(LKM) 399 if (count == auio.uio_resid && vn_union_readdir_hook) { 400 struct vnode *ovp = vp; 401 402 error = (*vn_union_readdir_hook)(&vp, fp, l); 403 if (error) 404 return (error); 405 if (vp != ovp) 406 goto unionread; 407 } 408#endif /* UNION || LKM */ 409 410 if (count == auio.uio_resid && (vp->v_flag & VROOT) && 411 (vp->v_mount->mnt_flag & MNT_UNION)) { 412 struct vnode *tvp = vp; 413 vp = vp->v_mount->mnt_vnodecovered; 414 VREF(vp); 415 fp->f_data = vp; 416 fp->f_offset = 0; 417 vrele(tvp); 418 goto unionread; 419 } 420 *done = count - auio.uio_resid; 421 return error; 422} 423 424/* 425 * File table vnode read routine. 426 */ 427static int 428vn_read(struct file *fp, off_t *offset, struct uio *uio, kauth_cred_t cred, 429 int flags) 430{ 431 struct vnode *vp = (struct vnode *)fp->f_data; 432 int count, error, ioflag; 433 struct lwp *l = curlwp; 434 435 VOP_LEASE(vp, l, cred, LEASE_READ); 436 ioflag = IO_ADV_ENCODE(fp->f_advice); 437 if (fp->f_flag & FNONBLOCK) 438 ioflag |= IO_NDELAY; 439 if ((fp->f_flag & (FFSYNC | FRSYNC)) == (FFSYNC | FRSYNC)) 440 ioflag |= IO_SYNC; 441 if (fp->f_flag & FALTIO) 442 ioflag |= IO_ALTSEMANTICS; 443 if (fp->f_flag & FDIRECT) 444 ioflag |= IO_DIRECT; 445 vn_lock(vp, LK_SHARED | LK_RETRY); 446 uio->uio_offset = *offset; 447 count = uio->uio_resid; 448 error = VOP_READ(vp, uio, ioflag, cred); 449 if (flags & FOF_UPDATE_OFFSET) 450 *offset += count - uio->uio_resid; 451 VOP_UNLOCK(vp, 0); 452 return (error); 453} 454 455/* 456 * File table vnode write routine. 457 */ 458static int 459vn_write(struct file *fp, off_t *offset, struct uio *uio, kauth_cred_t cred, 460 int flags) 461{ 462 struct vnode *vp = (struct vnode *)fp->f_data; 463 struct mount *mp; 464 int count, error, ioflag = IO_UNIT; 465 struct lwp *l = curlwp; 466 467 if (vp->v_type == VREG && (fp->f_flag & O_APPEND)) 468 ioflag |= IO_APPEND; 469 if (fp->f_flag & FNONBLOCK) 470 ioflag |= IO_NDELAY; 471 if (fp->f_flag & FFSYNC || 472 (vp->v_mount && (vp->v_mount->mnt_flag & MNT_SYNCHRONOUS))) 473 ioflag |= IO_SYNC; 474 else if (fp->f_flag & FDSYNC) 475 ioflag |= IO_DSYNC; 476 if (fp->f_flag & FALTIO) 477 ioflag |= IO_ALTSEMANTICS; 478 if (fp->f_flag & FDIRECT) 479 ioflag |= IO_DIRECT; 480 mp = NULL; 481 if (vp->v_type != VCHR && 482 (error = vn_start_write(vp, &mp, V_WAIT | V_PCATCH)) != 0) 483 return (error); 484 VOP_LEASE(vp, l, cred, LEASE_WRITE); 485 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 486 uio->uio_offset = *offset; 487 count = uio->uio_resid; 488 error = VOP_WRITE(vp, uio, ioflag, cred); 489 if (flags & FOF_UPDATE_OFFSET) { 490 if (ioflag & IO_APPEND) 491 *offset = uio->uio_offset; 492 else 493 *offset += count - uio->uio_resid; 494 } 495 VOP_UNLOCK(vp, 0); 496 vn_finished_write(mp, 0); 497 return (error); 498} 499 500/* 501 * File table vnode stat routine. 502 */ 503static int 504vn_statfile(struct file *fp, struct stat *sb, struct lwp *l) 505{ 506 struct vnode *vp = (struct vnode *)fp->f_data; 507 508 return vn_stat(vp, sb, l); 509} 510 511int 512vn_stat(struct vnode *vp, struct stat *sb, struct lwp *l) 513{ 514 struct vattr va; 515 int error; 516 mode_t mode; 517 518 error = VOP_GETATTR(vp, &va, l->l_cred, l); 519 if (error) 520 return (error); 521 /* 522 * Copy from vattr table 523 */ 524 sb->st_dev = va.va_fsid; 525 sb->st_ino = va.va_fileid; 526 mode = va.va_mode; 527 switch (vp->v_type) { 528 case VREG: 529 mode |= S_IFREG; 530 break; 531 case VDIR: 532 mode |= S_IFDIR; 533 break; 534 case VBLK: 535 mode |= S_IFBLK; 536 break; 537 case VCHR: 538 mode |= S_IFCHR; 539 break; 540 case VLNK: 541 mode |= S_IFLNK; 542 break; 543 case VSOCK: 544 mode |= S_IFSOCK; 545 break; 546 case VFIFO: 547 mode |= S_IFIFO; 548 break; 549 default: 550 return (EBADF); 551 }; 552 sb->st_mode = mode; 553 sb->st_nlink = va.va_nlink; 554 sb->st_uid = va.va_uid; 555 sb->st_gid = va.va_gid; 556 sb->st_rdev = va.va_rdev; 557 sb->st_size = va.va_size; 558 sb->st_atimespec = va.va_atime; 559 sb->st_mtimespec = va.va_mtime; 560 sb->st_ctimespec = va.va_ctime; 561 sb->st_birthtimespec = va.va_birthtime; 562 sb->st_blksize = va.va_blocksize; 563 sb->st_flags = va.va_flags; 564 sb->st_gen = 0; 565 sb->st_blocks = va.va_bytes / S_BLKSIZE; 566 return (0); 567} 568 569/* 570 * File table vnode fcntl routine. 571 */ 572static int 573vn_fcntl(struct file *fp, u_int com, void *data, struct lwp *l) 574{ 575 struct vnode *vp = ((struct vnode *)fp->f_data); 576 int error; 577 578 error = VOP_FCNTL(vp, com, data, fp->f_flag, l->l_cred, l); 579 return (error); 580} 581 582/* 583 * File table vnode ioctl routine. 584 */ 585static int 586vn_ioctl(struct file *fp, u_long com, void *data, struct lwp *l) 587{ 588 struct vnode *vp = ((struct vnode *)fp->f_data), *ovp; 589 struct proc *p = l->l_proc; 590 struct vattr vattr; 591 int error; 592 593 switch (vp->v_type) { 594 595 case VREG: 596 case VDIR: 597 if (com == FIONREAD) { 598 error = VOP_GETATTR(vp, &vattr, l->l_cred, l); 599 if (error) 600 return (error); 601 *(int *)data = vattr.va_size - fp->f_offset; 602 return (0); 603 } 604 if ((com == FIONWRITE) || (com == FIONSPACE)) { 605 /* 606 * Files don't have send queues, so there never 607 * are any bytes in them, nor is there any 608 * open space in them. 609 */ 610 *(int *)data = 0; 611 return (0); 612 } 613 if (com == FIOGETBMAP) { 614 daddr_t *block; 615 616 if (*(daddr_t *)data < 0) 617 return (EINVAL); 618 block = (daddr_t *)data; 619 return (VOP_BMAP(vp, *block, NULL, block, NULL)); 620 } 621 if (com == OFIOGETBMAP) { 622 daddr_t ibn, obn; 623 624 if (*(int32_t *)data < 0) 625 return (EINVAL); 626 ibn = (daddr_t)*(int32_t *)data; 627 error = VOP_BMAP(vp, ibn, NULL, &obn, NULL); 628 *(int32_t *)data = (int32_t)obn; 629 return error; 630 } 631 if (com == FIONBIO || com == FIOASYNC) /* XXX */ 632 return (0); /* XXX */ 633 /* fall into ... */ 634 case VFIFO: 635 case VCHR: 636 case VBLK: 637 error = VOP_IOCTL(vp, com, data, fp->f_flag, 638 l->l_cred, l); 639 if (error == 0 && com == TIOCSCTTY) { 640 VREF(vp); 641 mutex_enter(&proclist_lock); 642 ovp = p->p_session->s_ttyvp; 643 p->p_session->s_ttyvp = vp; 644 mutex_exit(&proclist_lock); 645 if (ovp != NULL) 646 vrele(ovp); 647 } 648 return (error); 649 650 default: 651 return (EPASSTHROUGH); 652 } 653} 654 655/* 656 * File table vnode poll routine. 657 */ 658static int 659vn_poll(struct file *fp, int events, struct lwp *l) 660{ 661 662 return (VOP_POLL(((struct vnode *)fp->f_data), events, l)); 663} 664 665/* 666 * File table vnode kqfilter routine. 667 */ 668int 669vn_kqfilter(struct file *fp, struct knote *kn) 670{ 671 672 return (VOP_KQFILTER((struct vnode *)fp->f_data, kn)); 673} 674 675/* 676 * Check that the vnode is still valid, and if so 677 * acquire requested lock. 678 */ 679int 680vn_lock(struct vnode *vp, int flags) 681{ 682 int error; 683 684#if 0 685 KASSERT(vp->v_usecount > 0 || (flags & LK_INTERLOCK) != 0 686 || (vp->v_flag & VONWORKLST) != 0); 687#endif 688 KASSERT((flags & 689 ~(LK_INTERLOCK|LK_SHARED|LK_EXCLUSIVE|LK_DRAIN|LK_NOWAIT|LK_RETRY| 690 LK_SETRECURSE|LK_CANRECURSE)) 691 == 0); 692 693 do { 694 if ((flags & LK_INTERLOCK) == 0) 695 simple_lock(&vp->v_interlock); 696 if (vp->v_flag & VXLOCK) { 697 if (flags & LK_NOWAIT) { 698 simple_unlock(&vp->v_interlock); 699 return EBUSY; 700 } 701 vp->v_flag |= VXWANT; 702 ltsleep(vp, PINOD | PNORELOCK, 703 "vn_lock", 0, &vp->v_interlock); 704 error = ENOENT; 705 } else { 706 error = VOP_LOCK(vp, 707 (flags & ~LK_RETRY) | LK_INTERLOCK); 708 if (error == 0 || error == EDEADLK || error == EBUSY) 709 return (error); 710 } 711 flags &= ~LK_INTERLOCK; 712 } while (flags & LK_RETRY); 713 return (error); 714} 715 716/* 717 * File table vnode close routine. 718 */ 719static int 720vn_closefile(struct file *fp, struct lwp *l) 721{ 722 723 return (vn_close(((struct vnode *)fp->f_data), fp->f_flag, 724 fp->f_cred, l)); 725} 726 727/* 728 * Enable LK_CANRECURSE on lock. Return prior status. 729 */ 730u_int 731vn_setrecurse(struct vnode *vp) 732{ 733 struct lock *lkp = &vp->v_lock; 734 u_int retval = lkp->lk_flags & LK_CANRECURSE; 735 736 lkp->lk_flags |= LK_CANRECURSE; 737 return retval; 738} 739 740/* 741 * Called when done with locksetrecurse. 742 */ 743void 744vn_restorerecurse(struct vnode *vp, u_int flags) 745{ 746 struct lock *lkp = &vp->v_lock; 747 748 lkp->lk_flags &= ~LK_CANRECURSE; 749 lkp->lk_flags |= flags; 750} 751 752int 753vn_cow_establish(struct vnode *vp, 754 int (*func)(void *, struct buf *), void *cookie) 755{ 756 int s; 757 struct spec_cow_entry *e; 758 759 MALLOC(e, struct spec_cow_entry *, sizeof(struct spec_cow_entry), 760 M_DEVBUF, M_WAITOK); 761 e->ce_func = func; 762 e->ce_cookie = cookie; 763 764 SPEC_COW_LOCK(vp->v_specinfo, s); 765 vp->v_spec_cow_req++; 766 while (vp->v_spec_cow_count > 0) 767 ltsleep(&vp->v_spec_cow_req, PRIBIO, "cowlist", 0, 768 &vp->v_spec_cow_slock); 769 770 SLIST_INSERT_HEAD(&vp->v_spec_cow_head, e, ce_list); 771 772 vp->v_spec_cow_req--; 773 if (vp->v_spec_cow_req == 0) 774 wakeup(&vp->v_spec_cow_req); 775 SPEC_COW_UNLOCK(vp->v_specinfo, s); 776 777 return 0; 778} 779 780int 781vn_cow_disestablish(struct vnode *vp, 782 int (*func)(void *, struct buf *), void *cookie) 783{ 784 int s; 785 struct spec_cow_entry *e; 786 787 SPEC_COW_LOCK(vp->v_specinfo, s); 788 vp->v_spec_cow_req++; 789 while (vp->v_spec_cow_count > 0) 790 ltsleep(&vp->v_spec_cow_req, PRIBIO, "cowlist", 0, 791 &vp->v_spec_cow_slock); 792 793 SLIST_FOREACH(e, &vp->v_spec_cow_head, ce_list) 794 if (e->ce_func == func && e->ce_cookie == cookie) { 795 SLIST_REMOVE(&vp->v_spec_cow_head, e, 796 spec_cow_entry, ce_list); 797 FREE(e, M_DEVBUF); 798 break; 799 } 800 801 vp->v_spec_cow_req--; 802 if (vp->v_spec_cow_req == 0) 803 wakeup(&vp->v_spec_cow_req); 804 SPEC_COW_UNLOCK(vp->v_specinfo, s); 805 806 return e ? 0 : EINVAL; 807} 808 809/* 810 * Simplified in-kernel wrapper calls for extended attribute access. 811 * Both calls pass in a NULL credential, authorizing a "kernel" access. 812 * Set IO_NODELOCKED in ioflg if the vnode is already locked. 813 */ 814int 815vn_extattr_get(struct vnode *vp, int ioflg, int attrnamespace, 816 const char *attrname, size_t *buflen, void *bf, struct lwp *l) 817{ 818 struct uio auio; 819 struct iovec aiov; 820 int error; 821 822 aiov.iov_len = *buflen; 823 aiov.iov_base = bf; 824 825 auio.uio_iov = &aiov; 826 auio.uio_iovcnt = 1; 827 auio.uio_rw = UIO_READ; 828 auio.uio_offset = 0; 829 auio.uio_resid = *buflen; 830 UIO_SETUP_SYSSPACE(&auio); 831 832 if ((ioflg & IO_NODELOCKED) == 0) 833 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 834 835 error = VOP_GETEXTATTR(vp, attrnamespace, attrname, &auio, NULL, NULL, 836 l); 837 838 if ((ioflg & IO_NODELOCKED) == 0) 839 VOP_UNLOCK(vp, 0); 840 841 if (error == 0) 842 *buflen = *buflen - auio.uio_resid; 843 844 return (error); 845} 846 847/* 848 * XXX Failure mode if partially written? 849 */ 850int 851vn_extattr_set(struct vnode *vp, int ioflg, int attrnamespace, 852 const char *attrname, size_t buflen, const void *bf, struct lwp *l) 853{ 854 struct uio auio; 855 struct iovec aiov; 856 struct mount *mp = NULL; /* XXX: GCC */ 857 int error; 858 859 aiov.iov_len = buflen; 860 aiov.iov_base = __UNCONST(bf); /* XXXUNCONST kills const */ 861 862 auio.uio_iov = &aiov; 863 auio.uio_iovcnt = 1; 864 auio.uio_rw = UIO_WRITE; 865 auio.uio_offset = 0; 866 auio.uio_resid = buflen; 867 UIO_SETUP_SYSSPACE(&auio); 868 869 if ((ioflg & IO_NODELOCKED) == 0) { 870 if ((error = vn_start_write(vp, &mp, V_WAIT)) != 0) 871 return (error); 872 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 873 } 874 875 error = VOP_SETEXTATTR(vp, attrnamespace, attrname, &auio, NULL, l); 876 877 if ((ioflg & IO_NODELOCKED) == 0) { 878 vn_finished_write(mp, 0); 879 VOP_UNLOCK(vp, 0); 880 } 881 882 return (error); 883} 884 885int 886vn_extattr_rm(struct vnode *vp, int ioflg, int attrnamespace, 887 const char *attrname, struct lwp *l) 888{ 889 struct mount *mp = NULL; /* XXX: GCC */ 890 int error; 891 892 if ((ioflg & IO_NODELOCKED) == 0) { 893 if ((error = vn_start_write(vp, &mp, V_WAIT)) != 0) 894 return (error); 895 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 896 } 897 898 error = VOP_DELETEEXTATTR(vp, attrnamespace, attrname, NULL, l); 899 if (error == EOPNOTSUPP) 900 error = VOP_SETEXTATTR(vp, attrnamespace, attrname, NULL, 901 NULL, l); 902 903 if ((ioflg & IO_NODELOCKED) == 0) { 904 vn_finished_write(mp, 0); 905 VOP_UNLOCK(vp, 0); 906 } 907 908 return (error); 909} 910 911/* 912 * OBSOLETE -- this function will be removed in the near future! 913 * 914 * Preparing to start a filesystem write operation. If the operation is 915 * permitted, then we bump the count of operations in progress and 916 * proceed. If a suspend request is in progress, we wait until the 917 * suspension is over, and then proceed. 918 * V_PCATCH adds PCATCH to the tsleep flags. 919 * V_WAIT waits until suspension is over. Otherwise returns EWOULDBLOCK. 920 * V_SLEEPONLY wait, but do not bump the operations count. 921 * V_LOWER this is a lower level operation. No further vnodes should be 922 * locked. Otherwise it is a upper level operation. No vnodes 923 * should be locked. 924 */ 925int 926vn_start_write(struct vnode *vp, struct mount **mpp, int flags) 927{ 928 929 /* 930 * If a vnode is provided, get and return the mount point that 931 * to which it will write. 932 */ 933 if (vp != NULL) { 934 *mpp = vp->v_mount; 935 } 936 return 0; 937} 938 939/* 940 * OBSOLETE -- this function will be removed in the near future! 941 * 942 * Filesystem write operation has completed. If we are suspending and this 943 * operation is the last one, notify the suspender that the suspension is 944 * now in effect. 945 */ 946void 947vn_finished_write(struct mount *mp, int flags) 948{ 949} 950 951void 952vn_ra_allocctx(struct vnode *vp) 953{ 954 struct uvm_ractx *ra = NULL; 955 956 if (vp->v_type != VREG) { 957 return; 958 } 959 if (vp->v_ractx != NULL) { 960 return; 961 } 962 simple_lock(&vp->v_interlock); 963 if (vp->v_ractx == NULL) { 964 simple_unlock(&vp->v_interlock); 965 ra = uvm_ra_allocctx(); 966 simple_lock(&vp->v_interlock); 967 if (ra != NULL && vp->v_ractx == NULL) { 968 vp->v_ractx = ra; 969 ra = NULL; 970 } 971 } 972 simple_unlock(&vp->v_interlock); 973 if (ra != NULL) { 974 uvm_ra_freectx(ra); 975 } 976} 977