vfs_export.c revision 47445
1/* 2 * Copyright (c) 1989, 1993 3 * The Regents of the University of California. All rights reserved. 4 * (c) UNIX System Laboratories, Inc. 5 * All or some portions of this file are derived from material licensed 6 * to the University of California by American Telephone and Telegraph 7 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 8 * the permission of UNIX System Laboratories, Inc. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the University of 21 * California, Berkeley and its contributors. 22 * 4. Neither the name of the University nor the names of its contributors 23 * may be used to endorse or promote products derived from this software 24 * without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 * 38 * @(#)vfs_subr.c 8.31 (Berkeley) 5/26/95 39 * $Id: vfs_subr.c,v 1.198 1999/05/14 20:40:15 luoqi Exp $ 40 */ 41 42/* 43 * External virtual filesystem routines 44 */ 45#include "opt_ddb.h" 46 47#include <sys/param.h> 48#include <sys/systm.h> 49#include <sys/conf.h> 50#include <sys/fcntl.h> 51#include <sys/kernel.h> 52#include <sys/proc.h> 53#include <sys/malloc.h> 54#include <sys/mount.h> 55#include <sys/socket.h> 56#include <sys/vnode.h> 57#include <sys/stat.h> 58#include <sys/buf.h> 59#include <sys/domain.h> 60#include <sys/dirent.h> 61#include <sys/vmmeter.h> 62 63#include <machine/limits.h> 64 65#include <vm/vm.h> 66#include <vm/vm_param.h> 67#include <vm/vm_prot.h> 68#include <vm/vm_object.h> 69#include <vm/vm_extern.h> 70#include <vm/pmap.h> 71#include <vm/vm_map.h> 72#include <vm/vm_page.h> 73#include <vm/vm_pager.h> 74#include <vm/vnode_pager.h> 75#include <vm/vm_zone.h> 76#include <sys/sysctl.h> 77 78#include <miscfs/specfs/specdev.h> 79 80static MALLOC_DEFINE(M_NETADDR, "Export Host", "Export host address structure"); 81 82static void insmntque __P((struct vnode *vp, struct mount *mp)); 83static void vclean __P((struct vnode *vp, int flags, struct proc *p)); 84static void vfree __P((struct vnode *)); 85static void vgonel __P((struct vnode *vp, struct proc *p)); 86static unsigned long numvnodes; 87SYSCTL_INT(_debug, OID_AUTO, numvnodes, CTLFLAG_RD, &numvnodes, 0, ""); 88 89enum vtype iftovt_tab[16] = { 90 VNON, VFIFO, VCHR, VNON, VDIR, VNON, VBLK, VNON, 91 VREG, VNON, VLNK, VNON, VSOCK, VNON, VNON, VBAD, 92}; 93int vttoif_tab[9] = { 94 0, S_IFREG, S_IFDIR, S_IFBLK, S_IFCHR, S_IFLNK, 95 S_IFSOCK, S_IFIFO, S_IFMT, 96}; 97 98static TAILQ_HEAD(freelst, vnode) vnode_free_list; /* vnode free list */ 99struct tobefreelist vnode_tobefree_list; /* vnode free list */ 100 101static u_long wantfreevnodes = 25; 102SYSCTL_INT(_debug, OID_AUTO, wantfreevnodes, CTLFLAG_RW, &wantfreevnodes, 0, ""); 103static u_long freevnodes = 0; 104SYSCTL_INT(_debug, OID_AUTO, freevnodes, CTLFLAG_RD, &freevnodes, 0, ""); 105 106int vfs_ioopt = 0; 107#ifdef ENABLE_VFS_IOOPT 108SYSCTL_INT(_vfs, OID_AUTO, ioopt, CTLFLAG_RW, &vfs_ioopt, 0, ""); 109#endif 110 111struct mntlist mountlist; /* mounted filesystem list */ 112struct simplelock mountlist_slock; 113struct simplelock mntvnode_slock; 114int nfs_mount_type = -1; 115#ifndef NULL_SIMPLELOCKS 116static struct simplelock mntid_slock; 117static struct simplelock vnode_free_list_slock; 118static struct simplelock spechash_slock; 119#endif 120struct nfs_public nfs_pub; /* publicly exported FS */ 121static vm_zone_t vnode_zone; 122 123/* 124 * The workitem queue. 125 */ 126#define SYNCER_MAXDELAY 32 127static int syncer_maxdelay = SYNCER_MAXDELAY; /* maximum delay time */ 128time_t syncdelay = 30; 129int rushjob; /* number of slots to run ASAP */ 130 131static int syncer_delayno = 0; 132static long syncer_mask; 133LIST_HEAD(synclist, vnode); 134static struct synclist *syncer_workitem_pending; 135 136int desiredvnodes; 137SYSCTL_INT(_kern, KERN_MAXVNODES, maxvnodes, CTLFLAG_RW, 138 &desiredvnodes, 0, "Maximum number of vnodes"); 139 140static void vfs_free_addrlist __P((struct netexport *nep)); 141static int vfs_free_netcred __P((struct radix_node *rn, void *w)); 142static int vfs_hang_addrlist __P((struct mount *mp, struct netexport *nep, 143 struct export_args *argp)); 144 145/* 146 * Initialize the vnode management data structures. 147 */ 148void 149vntblinit() 150{ 151 152 desiredvnodes = maxproc + cnt.v_page_count / 4; 153 simple_lock_init(&mntvnode_slock); 154 simple_lock_init(&mntid_slock); 155 simple_lock_init(&spechash_slock); 156 TAILQ_INIT(&vnode_free_list); 157 TAILQ_INIT(&vnode_tobefree_list); 158 simple_lock_init(&vnode_free_list_slock); 159 CIRCLEQ_INIT(&mountlist); 160 vnode_zone = zinit("VNODE", sizeof (struct vnode), 0, 0, 5); 161 /* 162 * Initialize the filesystem syncer. 163 */ 164 syncer_workitem_pending = hashinit(syncer_maxdelay, M_VNODE, 165 &syncer_mask); 166 syncer_maxdelay = syncer_mask + 1; 167} 168 169/* 170 * Mark a mount point as busy. Used to synchronize access and to delay 171 * unmounting. Interlock is not released on failure. 172 */ 173int 174vfs_busy(mp, flags, interlkp, p) 175 struct mount *mp; 176 int flags; 177 struct simplelock *interlkp; 178 struct proc *p; 179{ 180 int lkflags; 181 182 if (mp->mnt_kern_flag & MNTK_UNMOUNT) { 183 if (flags & LK_NOWAIT) 184 return (ENOENT); 185 mp->mnt_kern_flag |= MNTK_MWAIT; 186 if (interlkp) { 187 simple_unlock(interlkp); 188 } 189 /* 190 * Since all busy locks are shared except the exclusive 191 * lock granted when unmounting, the only place that a 192 * wakeup needs to be done is at the release of the 193 * exclusive lock at the end of dounmount. 194 */ 195 tsleep((caddr_t)mp, PVFS, "vfs_busy", 0); 196 if (interlkp) { 197 simple_lock(interlkp); 198 } 199 return (ENOENT); 200 } 201 lkflags = LK_SHARED | LK_NOPAUSE; 202 if (interlkp) 203 lkflags |= LK_INTERLOCK; 204 if (lockmgr(&mp->mnt_lock, lkflags, interlkp, p)) 205 panic("vfs_busy: unexpected lock failure"); 206 return (0); 207} 208 209/* 210 * Free a busy filesystem. 211 */ 212void 213vfs_unbusy(mp, p) 214 struct mount *mp; 215 struct proc *p; 216{ 217 218 lockmgr(&mp->mnt_lock, LK_RELEASE, NULL, p); 219} 220 221/* 222 * Lookup a filesystem type, and if found allocate and initialize 223 * a mount structure for it. 224 * 225 * Devname is usually updated by mount(8) after booting. 226 */ 227int 228vfs_rootmountalloc(fstypename, devname, mpp) 229 char *fstypename; 230 char *devname; 231 struct mount **mpp; 232{ 233 struct proc *p = curproc; /* XXX */ 234 struct vfsconf *vfsp; 235 struct mount *mp; 236 237 if (fstypename == NULL) 238 return (ENODEV); 239 for (vfsp = vfsconf; vfsp; vfsp = vfsp->vfc_next) 240 if (!strcmp(vfsp->vfc_name, fstypename)) 241 break; 242 if (vfsp == NULL) 243 return (ENODEV); 244 mp = malloc((u_long)sizeof(struct mount), M_MOUNT, M_WAITOK); 245 bzero((char *)mp, (u_long)sizeof(struct mount)); 246 lockinit(&mp->mnt_lock, PVFS, "vfslock", 0, LK_NOPAUSE); 247 (void)vfs_busy(mp, LK_NOWAIT, 0, p); 248 LIST_INIT(&mp->mnt_vnodelist); 249 mp->mnt_vfc = vfsp; 250 mp->mnt_op = vfsp->vfc_vfsops; 251 mp->mnt_flag = MNT_RDONLY; 252 mp->mnt_vnodecovered = NULLVP; 253 vfsp->vfc_refcount++; 254 mp->mnt_stat.f_type = vfsp->vfc_typenum; 255 mp->mnt_flag |= vfsp->vfc_flags & MNT_VISFLAGMASK; 256 strncpy(mp->mnt_stat.f_fstypename, vfsp->vfc_name, MFSNAMELEN); 257 mp->mnt_stat.f_mntonname[0] = '/'; 258 mp->mnt_stat.f_mntonname[1] = 0; 259 (void) copystr(devname, mp->mnt_stat.f_mntfromname, MNAMELEN - 1, 0); 260 *mpp = mp; 261 return (0); 262} 263 264/* 265 * Find an appropriate filesystem to use for the root. If a filesystem 266 * has not been preselected, walk through the list of known filesystems 267 * trying those that have mountroot routines, and try them until one 268 * works or we have tried them all. 269 */ 270#ifdef notdef /* XXX JH */ 271int 272lite2_vfs_mountroot() 273{ 274 struct vfsconf *vfsp; 275 extern int (*lite2_mountroot) __P((void)); 276 int error; 277 278 if (lite2_mountroot != NULL) 279 return ((*lite2_mountroot)()); 280 for (vfsp = vfsconf; vfsp; vfsp = vfsp->vfc_next) { 281 if (vfsp->vfc_mountroot == NULL) 282 continue; 283 if ((error = (*vfsp->vfc_mountroot)()) == 0) 284 return (0); 285 printf("%s_mountroot failed: %d\n", vfsp->vfc_name, error); 286 } 287 return (ENODEV); 288} 289#endif 290 291/* 292 * Lookup a mount point by filesystem identifier. 293 */ 294struct mount * 295vfs_getvfs(fsid) 296 fsid_t *fsid; 297{ 298 register struct mount *mp; 299 300 simple_lock(&mountlist_slock); 301 for (mp = mountlist.cqh_first; mp != (void *)&mountlist; 302 mp = mp->mnt_list.cqe_next) { 303 if (mp->mnt_stat.f_fsid.val[0] == fsid->val[0] && 304 mp->mnt_stat.f_fsid.val[1] == fsid->val[1]) { 305 simple_unlock(&mountlist_slock); 306 return (mp); 307 } 308 } 309 simple_unlock(&mountlist_slock); 310 return ((struct mount *) 0); 311} 312 313/* 314 * Get a new unique fsid 315 */ 316void 317vfs_getnewfsid(mp) 318 struct mount *mp; 319{ 320 static u_short xxxfs_mntid; 321 322 fsid_t tfsid; 323 int mtype; 324 325 simple_lock(&mntid_slock); 326 mtype = mp->mnt_vfc->vfc_typenum; 327 mp->mnt_stat.f_fsid.val[0] = (nblkdev + mtype) * 256; 328 mp->mnt_stat.f_fsid.val[1] = mtype; 329 if (xxxfs_mntid == 0) 330 ++xxxfs_mntid; 331 tfsid.val[0] = (nblkdev + mtype) * 256 | xxxfs_mntid; 332 tfsid.val[1] = mtype; 333 if (mountlist.cqh_first != (void *)&mountlist) { 334 while (vfs_getvfs(&tfsid)) { 335 tfsid.val[0]++; 336 xxxfs_mntid++; 337 } 338 } 339 mp->mnt_stat.f_fsid.val[0] = tfsid.val[0]; 340 simple_unlock(&mntid_slock); 341} 342 343/* 344 * Set vnode attributes to VNOVAL 345 */ 346void 347vattr_null(vap) 348 register struct vattr *vap; 349{ 350 351 vap->va_type = VNON; 352 vap->va_size = VNOVAL; 353 vap->va_bytes = VNOVAL; 354 vap->va_mode = VNOVAL; 355 vap->va_nlink = VNOVAL; 356 vap->va_uid = VNOVAL; 357 vap->va_gid = VNOVAL; 358 vap->va_fsid = VNOVAL; 359 vap->va_fileid = VNOVAL; 360 vap->va_blocksize = VNOVAL; 361 vap->va_rdev = VNOVAL; 362 vap->va_atime.tv_sec = VNOVAL; 363 vap->va_atime.tv_nsec = VNOVAL; 364 vap->va_mtime.tv_sec = VNOVAL; 365 vap->va_mtime.tv_nsec = VNOVAL; 366 vap->va_ctime.tv_sec = VNOVAL; 367 vap->va_ctime.tv_nsec = VNOVAL; 368 vap->va_flags = VNOVAL; 369 vap->va_gen = VNOVAL; 370 vap->va_vaflags = 0; 371} 372 373/* 374 * Routines having to do with the management of the vnode table. 375 */ 376extern vop_t **dead_vnodeop_p; 377 378/* 379 * Return the next vnode from the free list. 380 */ 381int 382getnewvnode(tag, mp, vops, vpp) 383 enum vtagtype tag; 384 struct mount *mp; 385 vop_t **vops; 386 struct vnode **vpp; 387{ 388 int s; 389 struct proc *p = curproc; /* XXX */ 390 struct vnode *vp, *tvp, *nvp; 391 vm_object_t object; 392 TAILQ_HEAD(freelst, vnode) vnode_tmp_list; 393 394 /* 395 * We take the least recently used vnode from the freelist 396 * if we can get it and it has no cached pages, and no 397 * namecache entries are relative to it. 398 * Otherwise we allocate a new vnode 399 */ 400 401 s = splbio(); 402 simple_lock(&vnode_free_list_slock); 403 TAILQ_INIT(&vnode_tmp_list); 404 405 for (vp = TAILQ_FIRST(&vnode_tobefree_list); vp; vp = nvp) { 406 nvp = TAILQ_NEXT(vp, v_freelist); 407 TAILQ_REMOVE(&vnode_tobefree_list, vp, v_freelist); 408 if (vp->v_flag & VAGE) { 409 TAILQ_INSERT_HEAD(&vnode_free_list, vp, v_freelist); 410 } else { 411 TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_freelist); 412 } 413 vp->v_flag &= ~(VTBFREE|VAGE); 414 vp->v_flag |= VFREE; 415 if (vp->v_usecount) 416 panic("tobe free vnode isn't"); 417 freevnodes++; 418 } 419 420 if (wantfreevnodes && freevnodes < wantfreevnodes) { 421 vp = NULL; 422 } else if (!wantfreevnodes && freevnodes <= desiredvnodes) { 423 /* 424 * XXX: this is only here to be backwards compatible 425 */ 426 vp = NULL; 427 } else { 428 for (vp = TAILQ_FIRST(&vnode_free_list); vp; vp = nvp) { 429 nvp = TAILQ_NEXT(vp, v_freelist); 430 if (!simple_lock_try(&vp->v_interlock)) 431 continue; 432 if (vp->v_usecount) 433 panic("free vnode isn't"); 434 435 object = vp->v_object; 436 if (object && (object->resident_page_count || object->ref_count)) { 437 printf("object inconsistant state: RPC: %d, RC: %d\n", 438 object->resident_page_count, object->ref_count); 439 /* Don't recycle if it's caching some pages */ 440 TAILQ_REMOVE(&vnode_free_list, vp, v_freelist); 441 TAILQ_INSERT_TAIL(&vnode_tmp_list, vp, v_freelist); 442 continue; 443 } else if (LIST_FIRST(&vp->v_cache_src)) { 444 /* Don't recycle if active in the namecache */ 445 simple_unlock(&vp->v_interlock); 446 continue; 447 } else { 448 break; 449 } 450 } 451 } 452 453 for (tvp = TAILQ_FIRST(&vnode_tmp_list); tvp; tvp = nvp) { 454 nvp = TAILQ_NEXT(tvp, v_freelist); 455 TAILQ_REMOVE(&vnode_tmp_list, tvp, v_freelist); 456 TAILQ_INSERT_TAIL(&vnode_free_list, tvp, v_freelist); 457 simple_unlock(&tvp->v_interlock); 458 } 459 460 if (vp) { 461 vp->v_flag |= VDOOMED; 462 TAILQ_REMOVE(&vnode_free_list, vp, v_freelist); 463 freevnodes--; 464 simple_unlock(&vnode_free_list_slock); 465 cache_purge(vp); 466 vp->v_lease = NULL; 467 if (vp->v_type != VBAD) { 468 vgonel(vp, p); 469 } else { 470 simple_unlock(&vp->v_interlock); 471 } 472 473#ifdef INVARIANTS 474 { 475 int s; 476 477 if (vp->v_data) 478 panic("cleaned vnode isn't"); 479 s = splbio(); 480 if (vp->v_numoutput) 481 panic("Clean vnode has pending I/O's"); 482 splx(s); 483 } 484#endif 485 vp->v_flag = 0; 486 vp->v_lastr = 0; 487 vp->v_lastw = 0; 488 vp->v_lasta = 0; 489 vp->v_cstart = 0; 490 vp->v_clen = 0; 491 vp->v_socket = 0; 492 vp->v_writecount = 0; /* XXX */ 493 vp->v_maxio = 0; 494 } else { 495 simple_unlock(&vnode_free_list_slock); 496 vp = (struct vnode *) zalloc(vnode_zone); 497 bzero((char *) vp, sizeof *vp); 498 simple_lock_init(&vp->v_interlock); 499 vp->v_dd = vp; 500 cache_purge(vp); 501 LIST_INIT(&vp->v_cache_src); 502 TAILQ_INIT(&vp->v_cache_dst); 503 numvnodes++; 504 } 505 506 TAILQ_INIT(&vp->v_cleanblkhd); 507 TAILQ_INIT(&vp->v_dirtyblkhd); 508 vp->v_type = VNON; 509 vp->v_tag = tag; 510 vp->v_op = vops; 511 insmntque(vp, mp); 512 *vpp = vp; 513 vp->v_usecount = 1; 514 vp->v_data = 0; 515 splx(s); 516 517 vfs_object_create(vp, p, p->p_ucred); 518 return (0); 519} 520 521/* 522 * Move a vnode from one mount queue to another. 523 */ 524static void 525insmntque(vp, mp) 526 register struct vnode *vp; 527 register struct mount *mp; 528{ 529 530 simple_lock(&mntvnode_slock); 531 /* 532 * Delete from old mount point vnode list, if on one. 533 */ 534 if (vp->v_mount != NULL) 535 LIST_REMOVE(vp, v_mntvnodes); 536 /* 537 * Insert into list of vnodes for the new mount point, if available. 538 */ 539 if ((vp->v_mount = mp) == NULL) { 540 simple_unlock(&mntvnode_slock); 541 return; 542 } 543 LIST_INSERT_HEAD(&mp->mnt_vnodelist, vp, v_mntvnodes); 544 simple_unlock(&mntvnode_slock); 545} 546 547/* 548 * Update outstanding I/O count and do wakeup if requested. 549 */ 550void 551vwakeup(bp) 552 register struct buf *bp; 553{ 554 register struct vnode *vp; 555 556 bp->b_flags &= ~B_WRITEINPROG; 557 if ((vp = bp->b_vp)) { 558 vp->v_numoutput--; 559 if (vp->v_numoutput < 0) 560 panic("vwakeup: neg numoutput"); 561 if ((vp->v_numoutput == 0) && (vp->v_flag & VBWAIT)) { 562 vp->v_flag &= ~VBWAIT; 563 wakeup((caddr_t) &vp->v_numoutput); 564 } 565 } 566} 567 568/* 569 * Flush out and invalidate all buffers associated with a vnode. 570 * Called with the underlying object locked. 571 */ 572int 573vinvalbuf(vp, flags, cred, p, slpflag, slptimeo) 574 register struct vnode *vp; 575 int flags; 576 struct ucred *cred; 577 struct proc *p; 578 int slpflag, slptimeo; 579{ 580 register struct buf *bp; 581 struct buf *nbp, *blist; 582 int s, error; 583 vm_object_t object; 584 585 if (flags & V_SAVE) { 586 s = splbio(); 587 while (vp->v_numoutput) { 588 vp->v_flag |= VBWAIT; 589 error = tsleep((caddr_t)&vp->v_numoutput, 590 slpflag | (PRIBIO + 1), "vinvlbuf", slptimeo); 591 if (error) { 592 splx(s); 593 return (error); 594 } 595 } 596 if (!TAILQ_EMPTY(&vp->v_dirtyblkhd)) { 597 splx(s); 598 if ((error = VOP_FSYNC(vp, cred, MNT_WAIT, p)) != 0) 599 return (error); 600 s = splbio(); 601 if (vp->v_numoutput > 0 || 602 !TAILQ_EMPTY(&vp->v_dirtyblkhd)) 603 panic("vinvalbuf: dirty bufs"); 604 } 605 splx(s); 606 } 607 s = splbio(); 608 for (;;) { 609 blist = TAILQ_FIRST(&vp->v_cleanblkhd); 610 if (!blist) 611 blist = TAILQ_FIRST(&vp->v_dirtyblkhd); 612 if (!blist) 613 break; 614 615 for (bp = blist; bp; bp = nbp) { 616 nbp = TAILQ_NEXT(bp, b_vnbufs); 617 if (bp->b_flags & B_BUSY) { 618 bp->b_flags |= B_WANTED; 619 error = tsleep((caddr_t) bp, 620 slpflag | (PRIBIO + 4), "vinvalbuf", 621 slptimeo); 622 if (error) { 623 splx(s); 624 return (error); 625 } 626 break; 627 } 628 /* 629 * XXX Since there are no node locks for NFS, I 630 * believe there is a slight chance that a delayed 631 * write will occur while sleeping just above, so 632 * check for it. Note that vfs_bio_awrite expects 633 * buffers to reside on a queue, while VOP_BWRITE and 634 * brelse do not. 635 */ 636 if (((bp->b_flags & (B_DELWRI | B_INVAL)) == B_DELWRI) && 637 (flags & V_SAVE)) { 638 639 if (bp->b_vp == vp) { 640 if (bp->b_flags & B_CLUSTEROK) { 641 vfs_bio_awrite(bp); 642 } else { 643 bremfree(bp); 644 bp->b_flags |= (B_BUSY | B_ASYNC); 645 VOP_BWRITE(bp); 646 } 647 } else { 648 bremfree(bp); 649 bp->b_flags |= B_BUSY; 650 (void) VOP_BWRITE(bp); 651 } 652 break; 653 } 654 bremfree(bp); 655 bp->b_flags |= (B_INVAL | B_NOCACHE | B_RELBUF | B_BUSY); 656 bp->b_flags &= ~B_ASYNC; 657 brelse(bp); 658 } 659 } 660 661 while (vp->v_numoutput > 0) { 662 vp->v_flag |= VBWAIT; 663 tsleep(&vp->v_numoutput, PVM, "vnvlbv", 0); 664 } 665 666 splx(s); 667 668 /* 669 * Destroy the copy in the VM cache, too. 670 */ 671 simple_lock(&vp->v_interlock); 672 object = vp->v_object; 673 if (object != NULL) { 674 vm_object_page_remove(object, 0, 0, 675 (flags & V_SAVE) ? TRUE : FALSE); 676 } 677 simple_unlock(&vp->v_interlock); 678 679 if (!TAILQ_EMPTY(&vp->v_dirtyblkhd) || !TAILQ_EMPTY(&vp->v_cleanblkhd)) 680 panic("vinvalbuf: flush failed"); 681 return (0); 682} 683 684/* 685 * Truncate a file's buffer and pages to a specified length. This 686 * is in lieu of the old vinvalbuf mechanism, which performed unneeded 687 * sync activity. 688 */ 689int 690vtruncbuf(vp, cred, p, length, blksize) 691 register struct vnode *vp; 692 struct ucred *cred; 693 struct proc *p; 694 off_t length; 695 int blksize; 696{ 697 register struct buf *bp; 698 struct buf *nbp; 699 int s, anyfreed; 700 int trunclbn; 701 702 /* 703 * Round up to the *next* lbn. 704 */ 705 trunclbn = (length + blksize - 1) / blksize; 706 707 s = splbio(); 708restart: 709 anyfreed = 1; 710 for (;anyfreed;) { 711 anyfreed = 0; 712 for (bp = TAILQ_FIRST(&vp->v_cleanblkhd); bp; bp = nbp) { 713 nbp = TAILQ_NEXT(bp, b_vnbufs); 714 if (bp->b_lblkno >= trunclbn) { 715 if (bp->b_flags & B_BUSY) { 716 bp->b_flags |= B_WANTED; 717 tsleep(bp, PRIBIO + 4, "vtrb1", 0); 718 goto restart; 719 } else { 720 bremfree(bp); 721 bp->b_flags |= (B_BUSY | B_INVAL | B_RELBUF); 722 bp->b_flags &= ~B_ASYNC; 723 brelse(bp); 724 anyfreed = 1; 725 } 726 if (nbp && (((nbp->b_xflags & B_VNCLEAN) == 0)|| 727 (nbp->b_vp != vp) || 728 (nbp->b_flags & B_DELWRI))) { 729 goto restart; 730 } 731 } 732 } 733 734 for (bp = TAILQ_FIRST(&vp->v_dirtyblkhd); bp; bp = nbp) { 735 nbp = TAILQ_NEXT(bp, b_vnbufs); 736 if (bp->b_lblkno >= trunclbn) { 737 if (bp->b_flags & B_BUSY) { 738 bp->b_flags |= B_WANTED; 739 tsleep(bp, PRIBIO + 4, "vtrb2", 0); 740 goto restart; 741 } else { 742 bremfree(bp); 743 bp->b_flags |= (B_BUSY | B_INVAL | B_RELBUF); 744 bp->b_flags &= ~B_ASYNC; 745 brelse(bp); 746 anyfreed = 1; 747 } 748 if (nbp && (((nbp->b_xflags & B_VNDIRTY) == 0)|| 749 (nbp->b_vp != vp) || 750 (nbp->b_flags & B_DELWRI) == 0)) { 751 goto restart; 752 } 753 } 754 } 755 } 756 757 if (length > 0) { 758restartsync: 759 for (bp = TAILQ_FIRST(&vp->v_dirtyblkhd); bp; bp = nbp) { 760 nbp = TAILQ_NEXT(bp, b_vnbufs); 761 if ((bp->b_flags & B_DELWRI) && (bp->b_lblkno < 0)) { 762 if (bp->b_flags & B_BUSY) { 763 bp->b_flags |= B_WANTED; 764 tsleep(bp, PRIBIO, "vtrb3", 0); 765 } else { 766 bremfree(bp); 767 bp->b_flags |= B_BUSY; 768 if (bp->b_vp == vp) { 769 bp->b_flags |= B_ASYNC; 770 } else { 771 bp->b_flags &= ~B_ASYNC; 772 } 773 VOP_BWRITE(bp); 774 } 775 goto restartsync; 776 } 777 778 } 779 } 780 781 while (vp->v_numoutput > 0) { 782 vp->v_flag |= VBWAIT; 783 tsleep(&vp->v_numoutput, PVM, "vbtrunc", 0); 784 } 785 786 splx(s); 787 788 vnode_pager_setsize(vp, length); 789 790 return (0); 791} 792 793/* 794 * Associate a buffer with a vnode. 795 */ 796void 797bgetvp(vp, bp) 798 register struct vnode *vp; 799 register struct buf *bp; 800{ 801 int s; 802 803 KASSERT(bp->b_vp == NULL, ("bgetvp: not free")); 804 805 vhold(vp); 806 bp->b_vp = vp; 807 if (vp->v_type == VBLK || vp->v_type == VCHR) 808 bp->b_dev = vp->v_rdev; 809 else 810 bp->b_dev = NODEV; 811 /* 812 * Insert onto list for new vnode. 813 */ 814 s = splbio(); 815 bp->b_xflags |= B_VNCLEAN; 816 bp->b_xflags &= ~B_VNDIRTY; 817 TAILQ_INSERT_TAIL(&vp->v_cleanblkhd, bp, b_vnbufs); 818 splx(s); 819} 820 821/* 822 * Disassociate a buffer from a vnode. 823 */ 824void 825brelvp(bp) 826 register struct buf *bp; 827{ 828 struct vnode *vp; 829 struct buflists *listheadp; 830 int s; 831 832 KASSERT(bp->b_vp != NULL, ("brelvp: NULL")); 833 834 /* 835 * Delete from old vnode list, if on one. 836 */ 837 vp = bp->b_vp; 838 s = splbio(); 839 if (bp->b_xflags & (B_VNDIRTY|B_VNCLEAN)) { 840 if (bp->b_xflags & B_VNDIRTY) 841 listheadp = &vp->v_dirtyblkhd; 842 else 843 listheadp = &vp->v_cleanblkhd; 844 TAILQ_REMOVE(listheadp, bp, b_vnbufs); 845 bp->b_xflags &= ~(B_VNDIRTY|B_VNCLEAN); 846 } 847 if ((vp->v_flag & VONWORKLST) && TAILQ_EMPTY(&vp->v_dirtyblkhd)) { 848 vp->v_flag &= ~VONWORKLST; 849 LIST_REMOVE(vp, v_synclist); 850 } 851 splx(s); 852 bp->b_vp = (struct vnode *) 0; 853 vdrop(vp); 854} 855 856/* 857 * The workitem queue. 858 * 859 * It is useful to delay writes of file data and filesystem metadata 860 * for tens of seconds so that quickly created and deleted files need 861 * not waste disk bandwidth being created and removed. To realize this, 862 * we append vnodes to a "workitem" queue. When running with a soft 863 * updates implementation, most pending metadata dependencies should 864 * not wait for more than a few seconds. Thus, mounted on block devices 865 * are delayed only about a half the time that file data is delayed. 866 * Similarly, directory updates are more critical, so are only delayed 867 * about a third the time that file data is delayed. Thus, there are 868 * SYNCER_MAXDELAY queues that are processed round-robin at a rate of 869 * one each second (driven off the filesystem syner process). The 870 * syncer_delayno variable indicates the next queue that is to be processed. 871 * Items that need to be processed soon are placed in this queue: 872 * 873 * syncer_workitem_pending[syncer_delayno] 874 * 875 * A delay of fifteen seconds is done by placing the request fifteen 876 * entries later in the queue: 877 * 878 * syncer_workitem_pending[(syncer_delayno + 15) & syncer_mask] 879 * 880 */ 881 882/* 883 * Add an item to the syncer work queue. 884 */ 885static void 886vn_syncer_add_to_worklist(struct vnode *vp, int delay) 887{ 888 int s, slot; 889 890 s = splbio(); 891 892 if (vp->v_flag & VONWORKLST) { 893 LIST_REMOVE(vp, v_synclist); 894 } 895 896 if (delay > syncer_maxdelay - 2) 897 delay = syncer_maxdelay - 2; 898 slot = (syncer_delayno + delay) & syncer_mask; 899 900 LIST_INSERT_HEAD(&syncer_workitem_pending[slot], vp, v_synclist); 901 vp->v_flag |= VONWORKLST; 902 splx(s); 903} 904 905struct proc *updateproc; 906static void sched_sync __P((void)); 907static const struct kproc_desc up_kp = { 908 "syncer", 909 sched_sync, 910 &updateproc 911}; 912SYSINIT_KT(syncer, SI_SUB_KTHREAD_UPDATE, SI_ORDER_FIRST, kproc_start, &up_kp) 913 914/* 915 * System filesystem synchronizer daemon. 916 */ 917void 918sched_sync(void) 919{ 920 struct synclist *slp; 921 struct vnode *vp; 922 long starttime; 923 int s; 924 struct proc *p = updateproc; 925 926 for (;;) { 927 starttime = time_second; 928 929 /* 930 * Push files whose dirty time has expired. Be careful 931 * of interrupt race on slp queue. 932 */ 933 s = splbio(); 934 slp = &syncer_workitem_pending[syncer_delayno]; 935 syncer_delayno += 1; 936 if (syncer_delayno == syncer_maxdelay) 937 syncer_delayno = 0; 938 splx(s); 939 940 while ((vp = LIST_FIRST(slp)) != NULL) { 941 if (VOP_ISLOCKED(vp) == 0) { 942 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p); 943 (void) VOP_FSYNC(vp, p->p_ucred, MNT_LAZY, p); 944 VOP_UNLOCK(vp, 0, p); 945 } 946 s = splbio(); 947 if (LIST_FIRST(slp) == vp) { 948 /* 949 * Note: v_tag VT_VFS vps can remain on the 950 * worklist too with no dirty blocks, but 951 * since sync_fsync() moves it to a different 952 * slot we are safe. 953 */ 954 if (TAILQ_EMPTY(&vp->v_dirtyblkhd) && 955 vp->v_type != VBLK) 956 panic("sched_sync: fsync failed vp %p tag %d", vp, vp->v_tag); 957 /* 958 * Put us back on the worklist. The worklist 959 * routine will remove us from our current 960 * position and then add us back in at a later 961 * position. 962 */ 963 vn_syncer_add_to_worklist(vp, syncdelay); 964 } 965 splx(s); 966 } 967 968 /* 969 * Do soft update processing. 970 */ 971 if (bioops.io_sync) 972 (*bioops.io_sync)(NULL); 973 974 /* 975 * The variable rushjob allows the kernel to speed up the 976 * processing of the filesystem syncer process. A rushjob 977 * value of N tells the filesystem syncer to process the next 978 * N seconds worth of work on its queue ASAP. Currently rushjob 979 * is used by the soft update code to speed up the filesystem 980 * syncer process when the incore state is getting so far 981 * ahead of the disk that the kernel memory pool is being 982 * threatened with exhaustion. 983 */ 984 if (rushjob > 0) { 985 rushjob -= 1; 986 continue; 987 } 988 /* 989 * If it has taken us less than a second to process the 990 * current work, then wait. Otherwise start right over 991 * again. We can still lose time if any single round 992 * takes more than two seconds, but it does not really 993 * matter as we are just trying to generally pace the 994 * filesystem activity. 995 */ 996 if (time_second == starttime) 997 tsleep(&lbolt, PPAUSE, "syncer", 0); 998 } 999} 1000 1001/* 1002 * Associate a p-buffer with a vnode. 1003 * 1004 * Also sets B_PAGING flag to indicate that vnode is not fully associated 1005 * with the buffer. i.e. the bp has not been linked into the vnode or 1006 * ref-counted. 1007 */ 1008void 1009pbgetvp(vp, bp) 1010 register struct vnode *vp; 1011 register struct buf *bp; 1012{ 1013 1014 KASSERT(bp->b_vp == NULL, ("pbgetvp: not free")); 1015 1016 bp->b_vp = vp; 1017 bp->b_flags |= B_PAGING; 1018 if (vp->v_type == VBLK || vp->v_type == VCHR) 1019 bp->b_dev = vp->v_rdev; 1020 else 1021 bp->b_dev = NODEV; 1022} 1023 1024/* 1025 * Disassociate a p-buffer from a vnode. 1026 */ 1027void 1028pbrelvp(bp) 1029 register struct buf *bp; 1030{ 1031 1032 KASSERT(bp->b_vp != NULL, ("pbrelvp: NULL")); 1033 1034#if !defined(MAX_PERF) 1035 /* XXX REMOVE ME */ 1036 if (bp->b_vnbufs.tqe_next != NULL) { 1037 panic( 1038 "relpbuf(): b_vp was probably reassignbuf()d %p %x", 1039 bp, 1040 (int)bp->b_flags 1041 ); 1042 } 1043#endif 1044 bp->b_vp = (struct vnode *) 0; 1045 bp->b_flags &= ~B_PAGING; 1046} 1047 1048void 1049pbreassignbuf(bp, newvp) 1050 struct buf *bp; 1051 struct vnode *newvp; 1052{ 1053#if !defined(MAX_PERF) 1054 if ((bp->b_flags & B_PAGING) == 0) { 1055 panic( 1056 "pbreassignbuf() on non phys bp %p", 1057 bp 1058 ); 1059 } 1060#endif 1061 bp->b_vp = newvp; 1062} 1063 1064/* 1065 * Reassign a buffer from one vnode to another. 1066 * Used to assign file specific control information 1067 * (indirect blocks) to the vnode to which they belong. 1068 */ 1069void 1070reassignbuf(bp, newvp) 1071 register struct buf *bp; 1072 register struct vnode *newvp; 1073{ 1074 struct buflists *listheadp; 1075 int delay; 1076 int s; 1077 1078 if (newvp == NULL) { 1079 printf("reassignbuf: NULL"); 1080 return; 1081 } 1082 1083#if !defined(MAX_PERF) 1084 /* 1085 * B_PAGING flagged buffers cannot be reassigned because their vp 1086 * is not fully linked in. 1087 */ 1088 if (bp->b_flags & B_PAGING) 1089 panic("cannot reassign paging buffer"); 1090#endif 1091 1092 s = splbio(); 1093 /* 1094 * Delete from old vnode list, if on one. 1095 */ 1096 if (bp->b_xflags & (B_VNDIRTY|B_VNCLEAN)) { 1097 if (bp->b_xflags & B_VNDIRTY) 1098 listheadp = &bp->b_vp->v_dirtyblkhd; 1099 else 1100 listheadp = &bp->b_vp->v_cleanblkhd; 1101 TAILQ_REMOVE(listheadp, bp, b_vnbufs); 1102 bp->b_xflags &= ~(B_VNDIRTY|B_VNCLEAN); 1103 if (bp->b_vp != newvp) { 1104 vdrop(bp->b_vp); 1105 bp->b_vp = NULL; /* for clarification */ 1106 } 1107 } 1108 /* 1109 * If dirty, put on list of dirty buffers; otherwise insert onto list 1110 * of clean buffers. 1111 */ 1112 if (bp->b_flags & B_DELWRI) { 1113 struct buf *tbp; 1114 1115 listheadp = &newvp->v_dirtyblkhd; 1116 if ((newvp->v_flag & VONWORKLST) == 0) { 1117 switch (newvp->v_type) { 1118 case VDIR: 1119 delay = syncdelay / 2; 1120 break; 1121 case VBLK: 1122 if (newvp->v_specmountpoint != NULL) { 1123 delay = syncdelay / 3; 1124 break; 1125 } 1126 /* fall through */ 1127 default: 1128 delay = syncdelay; 1129 } 1130 vn_syncer_add_to_worklist(newvp, delay); 1131 } 1132 bp->b_xflags |= B_VNDIRTY; 1133 tbp = TAILQ_FIRST(listheadp); 1134 if (tbp == NULL || 1135 (bp->b_lblkno >= 0 && tbp->b_lblkno > bp->b_lblkno)) { 1136 TAILQ_INSERT_HEAD(listheadp, bp, b_vnbufs); 1137 } else { 1138 if (bp->b_lblkno >= 0) { 1139 struct buf *ttbp; 1140 while ((ttbp = TAILQ_NEXT(tbp, b_vnbufs)) && 1141 (ttbp->b_lblkno < bp->b_lblkno)) { 1142 tbp = ttbp; 1143 } 1144 TAILQ_INSERT_AFTER(listheadp, tbp, bp, b_vnbufs); 1145 } else { 1146 TAILQ_INSERT_TAIL(listheadp, bp, b_vnbufs); 1147 } 1148 } 1149 } else { 1150 bp->b_xflags |= B_VNCLEAN; 1151 TAILQ_INSERT_TAIL(&newvp->v_cleanblkhd, bp, b_vnbufs); 1152 if ((newvp->v_flag & VONWORKLST) && 1153 TAILQ_EMPTY(&newvp->v_dirtyblkhd)) { 1154 newvp->v_flag &= ~VONWORKLST; 1155 LIST_REMOVE(newvp, v_synclist); 1156 } 1157 } 1158 if (bp->b_vp != newvp) { 1159 bp->b_vp = newvp; 1160 vhold(bp->b_vp); 1161 } 1162 splx(s); 1163} 1164 1165/* 1166 * Create a vnode for a block device. 1167 * Used for mounting the root file system. 1168 */ 1169int 1170bdevvp(dev, vpp) 1171 dev_t dev; 1172 struct vnode **vpp; 1173{ 1174 register struct vnode *vp; 1175 struct vnode *nvp; 1176 int error; 1177 1178 if (dev == NODEV || major(dev) >= nblkdev) { 1179 *vpp = NULLVP; 1180 return (ENXIO); 1181 } 1182 error = getnewvnode(VT_NON, (struct mount *)0, spec_vnodeop_p, &nvp); 1183 if (error) { 1184 *vpp = NULLVP; 1185 return (error); 1186 } 1187 vp = nvp; 1188 vp->v_type = VBLK; 1189 if ((nvp = checkalias(vp, dev2udev(dev), (struct mount *)0)) != NULL) { 1190 vput(vp); 1191 vp = nvp; 1192 } 1193 *vpp = vp; 1194 return (0); 1195} 1196 1197/* 1198 * Check to see if the new vnode represents a special device 1199 * for which we already have a vnode (either because of 1200 * bdevvp() or because of a different vnode representing 1201 * the same block device). If such an alias exists, deallocate 1202 * the existing contents and return the aliased vnode. The 1203 * caller is responsible for filling it with its new contents. 1204 */ 1205struct vnode * 1206checkalias(nvp, nvp_rdev, mp) 1207 register struct vnode *nvp; 1208 udev_t nvp_rdev; 1209 struct mount *mp; 1210{ 1211 struct proc *p = curproc; /* XXX */ 1212 struct vnode *vp; 1213 struct vnode **vpp; 1214 int rmaj = umajor(nvp_rdev); 1215 dev_t dev; 1216 1217 if (nvp->v_type != VBLK && nvp->v_type != VCHR) 1218 return (NULLVP); 1219 1220 dev = udev2dev(nvp_rdev, 2); 1221 1222 vpp = &speclisth[SPECHASH(dev)]; 1223loop: 1224 simple_lock(&spechash_slock); 1225 for (vp = *vpp; vp; vp = vp->v_specnext) { 1226 if (dev != vp->v_rdev || nvp->v_type != vp->v_type) 1227 continue; 1228 /* 1229 * Alias, but not in use, so flush it out. 1230 * Only alias active device nodes. 1231 * Not sure why we don't re-use this like we do below. 1232 */ 1233 simple_lock(&vp->v_interlock); 1234 if (vp->v_usecount == 0) { 1235 simple_unlock(&spechash_slock); 1236 vgonel(vp, p); 1237 goto loop; 1238 } 1239 if (vget(vp, LK_EXCLUSIVE | LK_INTERLOCK, p)) { 1240 /* 1241 * It dissappeared, and we may have slept. 1242 * Restart from the beginning 1243 */ 1244 simple_unlock(&spechash_slock); 1245 goto loop; 1246 } 1247 break; 1248 } 1249 /* 1250 * It would be a lot clearer what is going on here if 1251 * this had been expressed as: 1252 * if ( vp && (vp->v_tag == VT_NULL)) 1253 * and the clauses had been swapped. 1254 */ 1255 if (vp == NULL || vp->v_tag != VT_NON) { 1256 struct specinfo *sinfo; 1257 1258 /* 1259 * Put the new vnode into the hash chain. 1260 * and if there was an alias, connect them. 1261 */ 1262 MALLOC(sinfo, struct specinfo *, 1263 sizeof(struct specinfo), M_VNODE, M_WAITOK); 1264 bzero(sinfo, sizeof(struct specinfo)); 1265 nvp->v_specinfo = sinfo; 1266 sinfo->si_rdev = dev; 1267 sinfo->si_hashchain = vpp; 1268 sinfo->si_specnext = *vpp; 1269 sinfo->si_bsize_phys = DEV_BSIZE; 1270 sinfo->si_bsize_best = BLKDEV_IOSIZE; 1271 sinfo->si_bsize_max = MAXBSIZE; 1272 1273 /* 1274 * Ask the device to fix up specinfo. Typically the 1275 * si_bsize_* parameters may need fixing up. 1276 */ 1277 1278 if (nvp->v_type == VBLK && rmaj < nblkdev) { 1279 if (bdevsw(dev) && bdevsw(dev)->d_parms) 1280 (*bdevsw(dev)->d_parms)(dev, sinfo, DPARM_GET); 1281 } else if (nvp->v_type == VCHR && rmaj < nchrdev) { 1282 if (devsw(dev) && devsw(dev)->d_parms) 1283 (*devsw(dev)->d_parms)(dev, sinfo, DPARM_GET); 1284 } 1285 1286 simple_unlock(&spechash_slock); 1287 *vpp = nvp; 1288 if (vp != NULLVP) { 1289 nvp->v_flag |= VALIASED; 1290 vp->v_flag |= VALIASED; 1291 vput(vp); 1292 } 1293 return (NULLVP); 1294 } 1295 /* 1296 * if ( vp && (vp->v_tag == VT_NULL)) 1297 * We have a vnode alias, but it is a trashed. 1298 * Make it look like it's newley allocated. (by getnewvnode()) 1299 * The caller should use this instead. 1300 */ 1301 simple_unlock(&spechash_slock); 1302 VOP_UNLOCK(vp, 0, p); 1303 simple_lock(&vp->v_interlock); 1304 vclean(vp, 0, p); 1305 vp->v_op = nvp->v_op; 1306 vp->v_tag = nvp->v_tag; 1307 nvp->v_type = VNON; 1308 insmntque(vp, mp); 1309 return (vp); 1310} 1311 1312/* 1313 * Grab a particular vnode from the free list, increment its 1314 * reference count and lock it. The vnode lock bit is set the 1315 * vnode is being eliminated in vgone. The process is awakened 1316 * when the transition is completed, and an error returned to 1317 * indicate that the vnode is no longer usable (possibly having 1318 * been changed to a new file system type). 1319 */ 1320int 1321vget(vp, flags, p) 1322 register struct vnode *vp; 1323 int flags; 1324 struct proc *p; 1325{ 1326 int error; 1327 1328 /* 1329 * If the vnode is in the process of being cleaned out for 1330 * another use, we wait for the cleaning to finish and then 1331 * return failure. Cleaning is determined by checking that 1332 * the VXLOCK flag is set. 1333 */ 1334 if ((flags & LK_INTERLOCK) == 0) { 1335 simple_lock(&vp->v_interlock); 1336 } 1337 if (vp->v_flag & VXLOCK) { 1338 vp->v_flag |= VXWANT; 1339 simple_unlock(&vp->v_interlock); 1340 tsleep((caddr_t)vp, PINOD, "vget", 0); 1341 return (ENOENT); 1342 } 1343 1344 vp->v_usecount++; 1345 1346 if (VSHOULDBUSY(vp)) 1347 vbusy(vp); 1348 if (flags & LK_TYPE_MASK) { 1349 if ((error = vn_lock(vp, flags | LK_INTERLOCK, p)) != 0) { 1350 /* 1351 * must expand vrele here because we do not want 1352 * to call VOP_INACTIVE if the reference count 1353 * drops back to zero since it was never really 1354 * active. We must remove it from the free list 1355 * before sleeping so that multiple processes do 1356 * not try to recycle it. 1357 */ 1358 simple_lock(&vp->v_interlock); 1359 vp->v_usecount--; 1360 if (VSHOULDFREE(vp)) 1361 vfree(vp); 1362 simple_unlock(&vp->v_interlock); 1363 } 1364 return (error); 1365 } 1366 simple_unlock(&vp->v_interlock); 1367 return (0); 1368} 1369 1370void 1371vref(struct vnode *vp) 1372{ 1373 simple_lock(&vp->v_interlock); 1374 vp->v_usecount++; 1375 simple_unlock(&vp->v_interlock); 1376} 1377 1378/* 1379 * Vnode put/release. 1380 * If count drops to zero, call inactive routine and return to freelist. 1381 */ 1382void 1383vrele(vp) 1384 struct vnode *vp; 1385{ 1386 struct proc *p = curproc; /* XXX */ 1387 1388 KASSERT(vp != NULL, ("vrele: null vp")); 1389 1390 simple_lock(&vp->v_interlock); 1391 1392 if (vp->v_usecount > 1) { 1393 1394 vp->v_usecount--; 1395 simple_unlock(&vp->v_interlock); 1396 1397 return; 1398 } 1399 1400 if (vp->v_usecount == 1) { 1401 1402 vp->v_usecount--; 1403 if (VSHOULDFREE(vp)) 1404 vfree(vp); 1405 /* 1406 * If we are doing a vput, the node is already locked, and we must 1407 * call VOP_INACTIVE with the node locked. So, in the case of 1408 * vrele, we explicitly lock the vnode before calling VOP_INACTIVE. 1409 */ 1410 if (vn_lock(vp, LK_EXCLUSIVE | LK_INTERLOCK, p) == 0) { 1411 VOP_INACTIVE(vp, p); 1412 } 1413 1414 } else { 1415#ifdef DIAGNOSTIC 1416 vprint("vrele: negative ref count", vp); 1417 simple_unlock(&vp->v_interlock); 1418#endif 1419 panic("vrele: negative ref cnt"); 1420 } 1421} 1422 1423void 1424vput(vp) 1425 struct vnode *vp; 1426{ 1427 struct proc *p = curproc; /* XXX */ 1428 1429 KASSERT(vp != NULL, ("vput: null vp")); 1430 1431 simple_lock(&vp->v_interlock); 1432 1433 if (vp->v_usecount > 1) { 1434 1435 vp->v_usecount--; 1436 VOP_UNLOCK(vp, LK_INTERLOCK, p); 1437 return; 1438 1439 } 1440 1441 if (vp->v_usecount == 1) { 1442 1443 vp->v_usecount--; 1444 if (VSHOULDFREE(vp)) 1445 vfree(vp); 1446 /* 1447 * If we are doing a vput, the node is already locked, and we must 1448 * call VOP_INACTIVE with the node locked. So, in the case of 1449 * vrele, we explicitly lock the vnode before calling VOP_INACTIVE. 1450 */ 1451 simple_unlock(&vp->v_interlock); 1452 VOP_INACTIVE(vp, p); 1453 1454 } else { 1455#ifdef DIAGNOSTIC 1456 vprint("vput: negative ref count", vp); 1457#endif 1458 panic("vput: negative ref cnt"); 1459 } 1460} 1461 1462/* 1463 * Somebody doesn't want the vnode recycled. 1464 */ 1465void 1466vhold(vp) 1467 register struct vnode *vp; 1468{ 1469 int s; 1470 1471 s = splbio(); 1472 vp->v_holdcnt++; 1473 if (VSHOULDBUSY(vp)) 1474 vbusy(vp); 1475 splx(s); 1476} 1477 1478/* 1479 * One less who cares about this vnode. 1480 */ 1481void 1482vdrop(vp) 1483 register struct vnode *vp; 1484{ 1485 int s; 1486 1487 s = splbio(); 1488 if (vp->v_holdcnt <= 0) 1489 panic("vdrop: holdcnt"); 1490 vp->v_holdcnt--; 1491 if (VSHOULDFREE(vp)) 1492 vfree(vp); 1493 splx(s); 1494} 1495 1496/* 1497 * Remove any vnodes in the vnode table belonging to mount point mp. 1498 * 1499 * If MNT_NOFORCE is specified, there should not be any active ones, 1500 * return error if any are found (nb: this is a user error, not a 1501 * system error). If MNT_FORCE is specified, detach any active vnodes 1502 * that are found. 1503 */ 1504#ifdef DIAGNOSTIC 1505static int busyprt = 0; /* print out busy vnodes */ 1506SYSCTL_INT(_debug, OID_AUTO, busyprt, CTLFLAG_RW, &busyprt, 0, ""); 1507#endif 1508 1509int 1510vflush(mp, skipvp, flags) 1511 struct mount *mp; 1512 struct vnode *skipvp; 1513 int flags; 1514{ 1515 struct proc *p = curproc; /* XXX */ 1516 struct vnode *vp, *nvp; 1517 int busy = 0; 1518 1519 simple_lock(&mntvnode_slock); 1520loop: 1521 for (vp = mp->mnt_vnodelist.lh_first; vp; vp = nvp) { 1522 /* 1523 * Make sure this vnode wasn't reclaimed in getnewvnode(). 1524 * Start over if it has (it won't be on the list anymore). 1525 */ 1526 if (vp->v_mount != mp) 1527 goto loop; 1528 nvp = vp->v_mntvnodes.le_next; 1529 /* 1530 * Skip over a selected vnode. 1531 */ 1532 if (vp == skipvp) 1533 continue; 1534 1535 simple_lock(&vp->v_interlock); 1536 /* 1537 * Skip over a vnodes marked VSYSTEM. 1538 */ 1539 if ((flags & SKIPSYSTEM) && (vp->v_flag & VSYSTEM)) { 1540 simple_unlock(&vp->v_interlock); 1541 continue; 1542 } 1543 /* 1544 * If WRITECLOSE is set, only flush out regular file vnodes 1545 * open for writing. 1546 */ 1547 if ((flags & WRITECLOSE) && 1548 (vp->v_writecount == 0 || vp->v_type != VREG)) { 1549 simple_unlock(&vp->v_interlock); 1550 continue; 1551 } 1552 1553 /* 1554 * With v_usecount == 0, all we need to do is clear out the 1555 * vnode data structures and we are done. 1556 */ 1557 if (vp->v_usecount == 0) { 1558 simple_unlock(&mntvnode_slock); 1559 vgonel(vp, p); 1560 simple_lock(&mntvnode_slock); 1561 continue; 1562 } 1563 1564 /* 1565 * If FORCECLOSE is set, forcibly close the vnode. For block 1566 * or character devices, revert to an anonymous device. For 1567 * all other files, just kill them. 1568 */ 1569 if (flags & FORCECLOSE) { 1570 simple_unlock(&mntvnode_slock); 1571 if (vp->v_type != VBLK && vp->v_type != VCHR) { 1572 vgonel(vp, p); 1573 } else { 1574 vclean(vp, 0, p); 1575 vp->v_op = spec_vnodeop_p; 1576 insmntque(vp, (struct mount *) 0); 1577 } 1578 simple_lock(&mntvnode_slock); 1579 continue; 1580 } 1581#ifdef DIAGNOSTIC 1582 if (busyprt) 1583 vprint("vflush: busy vnode", vp); 1584#endif 1585 simple_unlock(&vp->v_interlock); 1586 busy++; 1587 } 1588 simple_unlock(&mntvnode_slock); 1589 if (busy) 1590 return (EBUSY); 1591 return (0); 1592} 1593 1594/* 1595 * Disassociate the underlying file system from a vnode. 1596 */ 1597static void 1598vclean(vp, flags, p) 1599 struct vnode *vp; 1600 int flags; 1601 struct proc *p; 1602{ 1603 int active; 1604 vm_object_t obj; 1605 1606 /* 1607 * Check to see if the vnode is in use. If so we have to reference it 1608 * before we clean it out so that its count cannot fall to zero and 1609 * generate a race against ourselves to recycle it. 1610 */ 1611 if ((active = vp->v_usecount)) 1612 vp->v_usecount++; 1613 1614 /* 1615 * Prevent the vnode from being recycled or brought into use while we 1616 * clean it out. 1617 */ 1618 if (vp->v_flag & VXLOCK) 1619 panic("vclean: deadlock"); 1620 vp->v_flag |= VXLOCK; 1621 /* 1622 * Even if the count is zero, the VOP_INACTIVE routine may still 1623 * have the object locked while it cleans it out. The VOP_LOCK 1624 * ensures that the VOP_INACTIVE routine is done with its work. 1625 * For active vnodes, it ensures that no other activity can 1626 * occur while the underlying object is being cleaned out. 1627 */ 1628 VOP_LOCK(vp, LK_DRAIN | LK_INTERLOCK, p); 1629 1630 /* 1631 * Clean out any buffers associated with the vnode. 1632 */ 1633 vinvalbuf(vp, V_SAVE, NOCRED, p, 0, 0); 1634 if ((obj = vp->v_object) != NULL) { 1635 if (obj->ref_count == 0) { 1636 /* 1637 * This is a normal way of shutting down the object/vnode 1638 * association. 1639 */ 1640 vm_object_terminate(obj); 1641 } else { 1642 /* 1643 * Woe to the process that tries to page now :-). 1644 */ 1645 vm_pager_deallocate(obj); 1646 } 1647 } 1648 1649 /* 1650 * If purging an active vnode, it must be closed and 1651 * deactivated before being reclaimed. Note that the 1652 * VOP_INACTIVE will unlock the vnode. 1653 */ 1654 if (active) { 1655 if (flags & DOCLOSE) 1656 VOP_CLOSE(vp, FNONBLOCK, NOCRED, p); 1657 VOP_INACTIVE(vp, p); 1658 } else { 1659 /* 1660 * Any other processes trying to obtain this lock must first 1661 * wait for VXLOCK to clear, then call the new lock operation. 1662 */ 1663 VOP_UNLOCK(vp, 0, p); 1664 } 1665 /* 1666 * Reclaim the vnode. 1667 */ 1668 if (VOP_RECLAIM(vp, p)) 1669 panic("vclean: cannot reclaim"); 1670 1671 if (active) 1672 vrele(vp); 1673 1674 cache_purge(vp); 1675 if (vp->v_vnlock) { 1676#if 0 /* This is the only place we have LK_DRAINED in the entire kernel ??? */ 1677#ifdef DIAGNOSTIC 1678 if ((vp->v_vnlock->lk_flags & LK_DRAINED) == 0) 1679 vprint("vclean: lock not drained", vp); 1680#endif 1681#endif 1682 FREE(vp->v_vnlock, M_VNODE); 1683 vp->v_vnlock = NULL; 1684 } 1685 1686 if (VSHOULDFREE(vp)) 1687 vfree(vp); 1688 1689 /* 1690 * Done with purge, notify sleepers of the grim news. 1691 */ 1692 vp->v_op = dead_vnodeop_p; 1693 vn_pollgone(vp); 1694 vp->v_tag = VT_NON; 1695 vp->v_flag &= ~VXLOCK; 1696 if (vp->v_flag & VXWANT) { 1697 vp->v_flag &= ~VXWANT; 1698 wakeup((caddr_t) vp); 1699 } 1700} 1701 1702/* 1703 * Eliminate all activity associated with the requested vnode 1704 * and with all vnodes aliased to the requested vnode. 1705 */ 1706int 1707vop_revoke(ap) 1708 struct vop_revoke_args /* { 1709 struct vnode *a_vp; 1710 int a_flags; 1711 } */ *ap; 1712{ 1713 struct vnode *vp, *vq; 1714 struct proc *p = curproc; /* XXX */ 1715 1716 KASSERT((ap->a_flags & REVOKEALL) != 0, ("vop_revoke")); 1717 1718 vp = ap->a_vp; 1719 simple_lock(&vp->v_interlock); 1720 1721 if (vp->v_flag & VALIASED) { 1722 /* 1723 * If a vgone (or vclean) is already in progress, 1724 * wait until it is done and return. 1725 */ 1726 if (vp->v_flag & VXLOCK) { 1727 vp->v_flag |= VXWANT; 1728 simple_unlock(&vp->v_interlock); 1729 tsleep((caddr_t)vp, PINOD, "vop_revokeall", 0); 1730 return (0); 1731 } 1732 /* 1733 * Ensure that vp will not be vgone'd while we 1734 * are eliminating its aliases. 1735 */ 1736 vp->v_flag |= VXLOCK; 1737 simple_unlock(&vp->v_interlock); 1738 while (vp->v_flag & VALIASED) { 1739 simple_lock(&spechash_slock); 1740 for (vq = *vp->v_hashchain; vq; vq = vq->v_specnext) { 1741 if (vq->v_rdev != vp->v_rdev || 1742 vq->v_type != vp->v_type || vp == vq) 1743 continue; 1744 simple_unlock(&spechash_slock); 1745 vgone(vq); 1746 break; 1747 } 1748 if (vq == NULLVP) { 1749 simple_unlock(&spechash_slock); 1750 } 1751 } 1752 /* 1753 * Remove the lock so that vgone below will 1754 * really eliminate the vnode after which time 1755 * vgone will awaken any sleepers. 1756 */ 1757 simple_lock(&vp->v_interlock); 1758 vp->v_flag &= ~VXLOCK; 1759 if (vp->v_flag & VXWANT) { 1760 vp->v_flag &= ~VXWANT; 1761 wakeup(vp); 1762 } 1763 } 1764 vgonel(vp, p); 1765 return (0); 1766} 1767 1768/* 1769 * Recycle an unused vnode to the front of the free list. 1770 * Release the passed interlock if the vnode will be recycled. 1771 */ 1772int 1773vrecycle(vp, inter_lkp, p) 1774 struct vnode *vp; 1775 struct simplelock *inter_lkp; 1776 struct proc *p; 1777{ 1778 1779 simple_lock(&vp->v_interlock); 1780 if (vp->v_usecount == 0) { 1781 if (inter_lkp) { 1782 simple_unlock(inter_lkp); 1783 } 1784 vgonel(vp, p); 1785 return (1); 1786 } 1787 simple_unlock(&vp->v_interlock); 1788 return (0); 1789} 1790 1791/* 1792 * Eliminate all activity associated with a vnode 1793 * in preparation for reuse. 1794 */ 1795void 1796vgone(vp) 1797 register struct vnode *vp; 1798{ 1799 struct proc *p = curproc; /* XXX */ 1800 1801 simple_lock(&vp->v_interlock); 1802 vgonel(vp, p); 1803} 1804 1805/* 1806 * vgone, with the vp interlock held. 1807 */ 1808static void 1809vgonel(vp, p) 1810 struct vnode *vp; 1811 struct proc *p; 1812{ 1813 int s; 1814 struct vnode *vq; 1815 struct vnode *vx; 1816 1817 /* 1818 * If a vgone (or vclean) is already in progress, 1819 * wait until it is done and return. 1820 */ 1821 if (vp->v_flag & VXLOCK) { 1822 vp->v_flag |= VXWANT; 1823 simple_unlock(&vp->v_interlock); 1824 tsleep((caddr_t)vp, PINOD, "vgone", 0); 1825 return; 1826 } 1827 1828 /* 1829 * Clean out the filesystem specific data. 1830 */ 1831 vclean(vp, DOCLOSE, p); 1832 simple_lock(&vp->v_interlock); 1833 1834 /* 1835 * Delete from old mount point vnode list, if on one. 1836 */ 1837 if (vp->v_mount != NULL) 1838 insmntque(vp, (struct mount *)0); 1839 /* 1840 * If special device, remove it from special device alias list 1841 * if it is on one. 1842 */ 1843 if ((vp->v_type == VBLK || vp->v_type == VCHR) && vp->v_specinfo != 0) { 1844 simple_lock(&spechash_slock); 1845 if (*vp->v_hashchain == vp) { 1846 *vp->v_hashchain = vp->v_specnext; 1847 } else { 1848 for (vq = *vp->v_hashchain; vq; vq = vq->v_specnext) { 1849 if (vq->v_specnext != vp) 1850 continue; 1851 vq->v_specnext = vp->v_specnext; 1852 break; 1853 } 1854 if (vq == NULL) 1855 panic("missing bdev"); 1856 } 1857 if (vp->v_flag & VALIASED) { 1858 vx = NULL; 1859 for (vq = *vp->v_hashchain; vq; vq = vq->v_specnext) { 1860 if (vq->v_rdev != vp->v_rdev || 1861 vq->v_type != vp->v_type) 1862 continue; 1863 if (vx) 1864 break; 1865 vx = vq; 1866 } 1867 if (vx == NULL) 1868 panic("missing alias"); 1869 if (vq == NULL) 1870 vx->v_flag &= ~VALIASED; 1871 vp->v_flag &= ~VALIASED; 1872 } 1873 simple_unlock(&spechash_slock); 1874 FREE(vp->v_specinfo, M_VNODE); 1875 vp->v_specinfo = NULL; 1876 } 1877 1878 /* 1879 * If it is on the freelist and not already at the head, 1880 * move it to the head of the list. The test of the back 1881 * pointer and the reference count of zero is because 1882 * it will be removed from the free list by getnewvnode, 1883 * but will not have its reference count incremented until 1884 * after calling vgone. If the reference count were 1885 * incremented first, vgone would (incorrectly) try to 1886 * close the previous instance of the underlying object. 1887 */ 1888 if (vp->v_usecount == 0 && !(vp->v_flag & VDOOMED)) { 1889 s = splbio(); 1890 simple_lock(&vnode_free_list_slock); 1891 if (vp->v_flag & VFREE) { 1892 TAILQ_REMOVE(&vnode_free_list, vp, v_freelist); 1893 } else if (vp->v_flag & VTBFREE) { 1894 TAILQ_REMOVE(&vnode_tobefree_list, vp, v_freelist); 1895 vp->v_flag &= ~VTBFREE; 1896 freevnodes++; 1897 } else 1898 freevnodes++; 1899 vp->v_flag |= VFREE; 1900 TAILQ_INSERT_HEAD(&vnode_free_list, vp, v_freelist); 1901 simple_unlock(&vnode_free_list_slock); 1902 splx(s); 1903 } 1904 1905 vp->v_type = VBAD; 1906 simple_unlock(&vp->v_interlock); 1907} 1908 1909/* 1910 * Lookup a vnode by device number. 1911 */ 1912int 1913vfinddev(dev, type, vpp) 1914 dev_t dev; 1915 enum vtype type; 1916 struct vnode **vpp; 1917{ 1918 register struct vnode *vp; 1919 int rc = 0; 1920 1921 simple_lock(&spechash_slock); 1922 for (vp = speclisth[SPECHASH(dev)]; vp; vp = vp->v_specnext) { 1923 if (dev != vp->v_rdev || type != vp->v_type) 1924 continue; 1925 *vpp = vp; 1926 rc = 1; 1927 break; 1928 } 1929 simple_unlock(&spechash_slock); 1930 return (rc); 1931} 1932 1933/* 1934 * Calculate the total number of references to a special device. 1935 */ 1936int 1937vcount(vp) 1938 register struct vnode *vp; 1939{ 1940 struct vnode *vq, *vnext; 1941 int count; 1942 1943loop: 1944 if ((vp->v_flag & VALIASED) == 0) 1945 return (vp->v_usecount); 1946 simple_lock(&spechash_slock); 1947 for (count = 0, vq = *vp->v_hashchain; vq; vq = vnext) { 1948 vnext = vq->v_specnext; 1949 if (vq->v_rdev != vp->v_rdev || vq->v_type != vp->v_type) 1950 continue; 1951 /* 1952 * Alias, but not in use, so flush it out. 1953 */ 1954 if (vq->v_usecount == 0 && vq != vp) { 1955 simple_unlock(&spechash_slock); 1956 vgone(vq); 1957 goto loop; 1958 } 1959 count += vq->v_usecount; 1960 } 1961 simple_unlock(&spechash_slock); 1962 return (count); 1963} 1964/* 1965 * Print out a description of a vnode. 1966 */ 1967static char *typename[] = 1968{"VNON", "VREG", "VDIR", "VBLK", "VCHR", "VLNK", "VSOCK", "VFIFO", "VBAD"}; 1969 1970void 1971vprint(label, vp) 1972 char *label; 1973 register struct vnode *vp; 1974{ 1975 char buf[96]; 1976 1977 if (label != NULL) 1978 printf("%s: %p: ", label, (void *)vp); 1979 else 1980 printf("%p: ", (void *)vp); 1981 printf("type %s, usecount %d, writecount %d, refcount %d,", 1982 typename[vp->v_type], vp->v_usecount, vp->v_writecount, 1983 vp->v_holdcnt); 1984 buf[0] = '\0'; 1985 if (vp->v_flag & VROOT) 1986 strcat(buf, "|VROOT"); 1987 if (vp->v_flag & VTEXT) 1988 strcat(buf, "|VTEXT"); 1989 if (vp->v_flag & VSYSTEM) 1990 strcat(buf, "|VSYSTEM"); 1991 if (vp->v_flag & VXLOCK) 1992 strcat(buf, "|VXLOCK"); 1993 if (vp->v_flag & VXWANT) 1994 strcat(buf, "|VXWANT"); 1995 if (vp->v_flag & VBWAIT) 1996 strcat(buf, "|VBWAIT"); 1997 if (vp->v_flag & VALIASED) 1998 strcat(buf, "|VALIASED"); 1999 if (vp->v_flag & VDOOMED) 2000 strcat(buf, "|VDOOMED"); 2001 if (vp->v_flag & VFREE) 2002 strcat(buf, "|VFREE"); 2003 if (vp->v_flag & VOBJBUF) 2004 strcat(buf, "|VOBJBUF"); 2005 if (buf[0] != '\0') 2006 printf(" flags (%s)", &buf[1]); 2007 if (vp->v_data == NULL) { 2008 printf("\n"); 2009 } else { 2010 printf("\n\t"); 2011 VOP_PRINT(vp); 2012 } 2013} 2014 2015#ifdef DDB 2016#include <ddb/ddb.h> 2017/* 2018 * List all of the locked vnodes in the system. 2019 * Called when debugging the kernel. 2020 */ 2021DB_SHOW_COMMAND(lockedvnodes, lockedvnodes) 2022{ 2023 struct proc *p = curproc; /* XXX */ 2024 struct mount *mp, *nmp; 2025 struct vnode *vp; 2026 2027 printf("Locked vnodes\n"); 2028 simple_lock(&mountlist_slock); 2029 for (mp = mountlist.cqh_first; mp != (void *)&mountlist; mp = nmp) { 2030 if (vfs_busy(mp, LK_NOWAIT, &mountlist_slock, p)) { 2031 nmp = mp->mnt_list.cqe_next; 2032 continue; 2033 } 2034 for (vp = mp->mnt_vnodelist.lh_first; 2035 vp != NULL; 2036 vp = vp->v_mntvnodes.le_next) { 2037 if (VOP_ISLOCKED(vp)) 2038 vprint((char *)0, vp); 2039 } 2040 simple_lock(&mountlist_slock); 2041 nmp = mp->mnt_list.cqe_next; 2042 vfs_unbusy(mp, p); 2043 } 2044 simple_unlock(&mountlist_slock); 2045} 2046#endif 2047 2048/* 2049 * Top level filesystem related information gathering. 2050 */ 2051static int sysctl_ovfs_conf __P(SYSCTL_HANDLER_ARGS); 2052 2053static int 2054vfs_sysctl SYSCTL_HANDLER_ARGS 2055{ 2056 int *name = (int *)arg1 - 1; /* XXX */ 2057 u_int namelen = arg2 + 1; /* XXX */ 2058 struct vfsconf *vfsp; 2059 2060#if 1 || defined(COMPAT_PRELITE2) 2061 /* Resolve ambiguity between VFS_VFSCONF and VFS_GENERIC. */ 2062 if (namelen == 1) 2063 return (sysctl_ovfs_conf(oidp, arg1, arg2, req)); 2064#endif 2065 2066#ifdef notyet 2067 /* all sysctl names at this level are at least name and field */ 2068 if (namelen < 2) 2069 return (ENOTDIR); /* overloaded */ 2070 if (name[0] != VFS_GENERIC) { 2071 for (vfsp = vfsconf; vfsp; vfsp = vfsp->vfc_next) 2072 if (vfsp->vfc_typenum == name[0]) 2073 break; 2074 if (vfsp == NULL) 2075 return (EOPNOTSUPP); 2076 return ((*vfsp->vfc_vfsops->vfs_sysctl)(&name[1], namelen - 1, 2077 oldp, oldlenp, newp, newlen, p)); 2078 } 2079#endif 2080 switch (name[1]) { 2081 case VFS_MAXTYPENUM: 2082 if (namelen != 2) 2083 return (ENOTDIR); 2084 return (SYSCTL_OUT(req, &maxvfsconf, sizeof(int))); 2085 case VFS_CONF: 2086 if (namelen != 3) 2087 return (ENOTDIR); /* overloaded */ 2088 for (vfsp = vfsconf; vfsp; vfsp = vfsp->vfc_next) 2089 if (vfsp->vfc_typenum == name[2]) 2090 break; 2091 if (vfsp == NULL) 2092 return (EOPNOTSUPP); 2093 return (SYSCTL_OUT(req, vfsp, sizeof *vfsp)); 2094 } 2095 return (EOPNOTSUPP); 2096} 2097 2098SYSCTL_NODE(_vfs, VFS_GENERIC, generic, CTLFLAG_RD, vfs_sysctl, 2099 "Generic filesystem"); 2100 2101#if 1 || defined(COMPAT_PRELITE2) 2102 2103static int 2104sysctl_ovfs_conf SYSCTL_HANDLER_ARGS 2105{ 2106 int error; 2107 struct vfsconf *vfsp; 2108 struct ovfsconf ovfs; 2109 2110 for (vfsp = vfsconf; vfsp; vfsp = vfsp->vfc_next) { 2111 ovfs.vfc_vfsops = vfsp->vfc_vfsops; /* XXX used as flag */ 2112 strcpy(ovfs.vfc_name, vfsp->vfc_name); 2113 ovfs.vfc_index = vfsp->vfc_typenum; 2114 ovfs.vfc_refcount = vfsp->vfc_refcount; 2115 ovfs.vfc_flags = vfsp->vfc_flags; 2116 error = SYSCTL_OUT(req, &ovfs, sizeof ovfs); 2117 if (error) 2118 return error; 2119 } 2120 return 0; 2121} 2122 2123#endif /* 1 || COMPAT_PRELITE2 */ 2124 2125#if 0 2126#define KINFO_VNODESLOP 10 2127/* 2128 * Dump vnode list (via sysctl). 2129 * Copyout address of vnode followed by vnode. 2130 */ 2131/* ARGSUSED */ 2132static int 2133sysctl_vnode SYSCTL_HANDLER_ARGS 2134{ 2135 struct proc *p = curproc; /* XXX */ 2136 struct mount *mp, *nmp; 2137 struct vnode *nvp, *vp; 2138 int error; 2139 2140#define VPTRSZ sizeof (struct vnode *) 2141#define VNODESZ sizeof (struct vnode) 2142 2143 req->lock = 0; 2144 if (!req->oldptr) /* Make an estimate */ 2145 return (SYSCTL_OUT(req, 0, 2146 (numvnodes + KINFO_VNODESLOP) * (VPTRSZ + VNODESZ))); 2147 2148 simple_lock(&mountlist_slock); 2149 for (mp = mountlist.cqh_first; mp != (void *)&mountlist; mp = nmp) { 2150 if (vfs_busy(mp, LK_NOWAIT, &mountlist_slock, p)) { 2151 nmp = mp->mnt_list.cqe_next; 2152 continue; 2153 } 2154again: 2155 simple_lock(&mntvnode_slock); 2156 for (vp = mp->mnt_vnodelist.lh_first; 2157 vp != NULL; 2158 vp = nvp) { 2159 /* 2160 * Check that the vp is still associated with 2161 * this filesystem. RACE: could have been 2162 * recycled onto the same filesystem. 2163 */ 2164 if (vp->v_mount != mp) { 2165 simple_unlock(&mntvnode_slock); 2166 goto again; 2167 } 2168 nvp = vp->v_mntvnodes.le_next; 2169 simple_unlock(&mntvnode_slock); 2170 if ((error = SYSCTL_OUT(req, &vp, VPTRSZ)) || 2171 (error = SYSCTL_OUT(req, vp, VNODESZ))) 2172 return (error); 2173 simple_lock(&mntvnode_slock); 2174 } 2175 simple_unlock(&mntvnode_slock); 2176 simple_lock(&mountlist_slock); 2177 nmp = mp->mnt_list.cqe_next; 2178 vfs_unbusy(mp, p); 2179 } 2180 simple_unlock(&mountlist_slock); 2181 2182 return (0); 2183} 2184#endif 2185 2186/* 2187 * XXX 2188 * Exporting the vnode list on large systems causes them to crash. 2189 * Exporting the vnode list on medium systems causes sysctl to coredump. 2190 */ 2191#if 0 2192SYSCTL_PROC(_kern, KERN_VNODE, vnode, CTLTYPE_OPAQUE|CTLFLAG_RD, 2193 0, 0, sysctl_vnode, "S,vnode", ""); 2194#endif 2195 2196/* 2197 * Check to see if a filesystem is mounted on a block device. 2198 */ 2199int 2200vfs_mountedon(vp) 2201 struct vnode *vp; 2202{ 2203 struct vnode *vq; 2204 int error = 0; 2205 2206 if (vp->v_specmountpoint != NULL) 2207 return (EBUSY); 2208 if (vp->v_flag & VALIASED) { 2209 simple_lock(&spechash_slock); 2210 for (vq = *vp->v_hashchain; vq; vq = vq->v_specnext) { 2211 if (vq->v_rdev != vp->v_rdev || 2212 vq->v_type != vp->v_type) 2213 continue; 2214 if (vq->v_specmountpoint != NULL) { 2215 error = EBUSY; 2216 break; 2217 } 2218 } 2219 simple_unlock(&spechash_slock); 2220 } 2221 return (error); 2222} 2223 2224/* 2225 * Unmount all filesystems. The list is traversed in reverse order 2226 * of mounting to avoid dependencies. 2227 */ 2228void 2229vfs_unmountall() 2230{ 2231 struct mount *mp, *nmp; 2232 struct proc *p; 2233 int error; 2234 2235 if (curproc != NULL) 2236 p = curproc; 2237 else 2238 p = initproc; /* XXX XXX should this be proc0? */ 2239 /* 2240 * Since this only runs when rebooting, it is not interlocked. 2241 */ 2242 for (mp = mountlist.cqh_last; mp != (void *)&mountlist; mp = nmp) { 2243 nmp = mp->mnt_list.cqe_prev; 2244 error = dounmount(mp, MNT_FORCE, p); 2245 if (error) { 2246 printf("unmount of %s failed (", 2247 mp->mnt_stat.f_mntonname); 2248 if (error == EBUSY) 2249 printf("BUSY)\n"); 2250 else 2251 printf("%d)\n", error); 2252 } 2253 } 2254} 2255 2256/* 2257 * Build hash lists of net addresses and hang them off the mount point. 2258 * Called by ufs_mount() to set up the lists of export addresses. 2259 */ 2260static int 2261vfs_hang_addrlist(mp, nep, argp) 2262 struct mount *mp; 2263 struct netexport *nep; 2264 struct export_args *argp; 2265{ 2266 register struct netcred *np; 2267 register struct radix_node_head *rnh; 2268 register int i; 2269 struct radix_node *rn; 2270 struct sockaddr *saddr, *smask = 0; 2271 struct domain *dom; 2272 int error; 2273 2274 if (argp->ex_addrlen == 0) { 2275 if (mp->mnt_flag & MNT_DEFEXPORTED) 2276 return (EPERM); 2277 np = &nep->ne_defexported; 2278 np->netc_exflags = argp->ex_flags; 2279 np->netc_anon = argp->ex_anon; 2280 np->netc_anon.cr_ref = 1; 2281 mp->mnt_flag |= MNT_DEFEXPORTED; 2282 return (0); 2283 } 2284 i = sizeof(struct netcred) + argp->ex_addrlen + argp->ex_masklen; 2285 np = (struct netcred *) malloc(i, M_NETADDR, M_WAITOK); 2286 bzero((caddr_t) np, i); 2287 saddr = (struct sockaddr *) (np + 1); 2288 if ((error = copyin(argp->ex_addr, (caddr_t) saddr, argp->ex_addrlen))) 2289 goto out; 2290 if (saddr->sa_len > argp->ex_addrlen) 2291 saddr->sa_len = argp->ex_addrlen; 2292 if (argp->ex_masklen) { 2293 smask = (struct sockaddr *) ((caddr_t) saddr + argp->ex_addrlen); 2294 error = copyin(argp->ex_mask, (caddr_t) smask, argp->ex_masklen); 2295 if (error) 2296 goto out; 2297 if (smask->sa_len > argp->ex_masklen) 2298 smask->sa_len = argp->ex_masklen; 2299 } 2300 i = saddr->sa_family; 2301 if ((rnh = nep->ne_rtable[i]) == 0) { 2302 /* 2303 * Seems silly to initialize every AF when most are not used, 2304 * do so on demand here 2305 */ 2306 for (dom = domains; dom; dom = dom->dom_next) 2307 if (dom->dom_family == i && dom->dom_rtattach) { 2308 dom->dom_rtattach((void **) &nep->ne_rtable[i], 2309 dom->dom_rtoffset); 2310 break; 2311 } 2312 if ((rnh = nep->ne_rtable[i]) == 0) { 2313 error = ENOBUFS; 2314 goto out; 2315 } 2316 } 2317 rn = (*rnh->rnh_addaddr) ((caddr_t) saddr, (caddr_t) smask, rnh, 2318 np->netc_rnodes); 2319 if (rn == 0 || np != (struct netcred *) rn) { /* already exists */ 2320 error = EPERM; 2321 goto out; 2322 } 2323 np->netc_exflags = argp->ex_flags; 2324 np->netc_anon = argp->ex_anon; 2325 np->netc_anon.cr_ref = 1; 2326 return (0); 2327out: 2328 free(np, M_NETADDR); 2329 return (error); 2330} 2331 2332/* ARGSUSED */ 2333static int 2334vfs_free_netcred(rn, w) 2335 struct radix_node *rn; 2336 void *w; 2337{ 2338 register struct radix_node_head *rnh = (struct radix_node_head *) w; 2339 2340 (*rnh->rnh_deladdr) (rn->rn_key, rn->rn_mask, rnh); 2341 free((caddr_t) rn, M_NETADDR); 2342 return (0); 2343} 2344 2345/* 2346 * Free the net address hash lists that are hanging off the mount points. 2347 */ 2348static void 2349vfs_free_addrlist(nep) 2350 struct netexport *nep; 2351{ 2352 register int i; 2353 register struct radix_node_head *rnh; 2354 2355 for (i = 0; i <= AF_MAX; i++) 2356 if ((rnh = nep->ne_rtable[i])) { 2357 (*rnh->rnh_walktree) (rnh, vfs_free_netcred, 2358 (caddr_t) rnh); 2359 free((caddr_t) rnh, M_RTABLE); 2360 nep->ne_rtable[i] = 0; 2361 } 2362} 2363 2364int 2365vfs_export(mp, nep, argp) 2366 struct mount *mp; 2367 struct netexport *nep; 2368 struct export_args *argp; 2369{ 2370 int error; 2371 2372 if (argp->ex_flags & MNT_DELEXPORT) { 2373 if (mp->mnt_flag & MNT_EXPUBLIC) { 2374 vfs_setpublicfs(NULL, NULL, NULL); 2375 mp->mnt_flag &= ~MNT_EXPUBLIC; 2376 } 2377 vfs_free_addrlist(nep); 2378 mp->mnt_flag &= ~(MNT_EXPORTED | MNT_DEFEXPORTED); 2379 } 2380 if (argp->ex_flags & MNT_EXPORTED) { 2381 if (argp->ex_flags & MNT_EXPUBLIC) { 2382 if ((error = vfs_setpublicfs(mp, nep, argp)) != 0) 2383 return (error); 2384 mp->mnt_flag |= MNT_EXPUBLIC; 2385 } 2386 if ((error = vfs_hang_addrlist(mp, nep, argp))) 2387 return (error); 2388 mp->mnt_flag |= MNT_EXPORTED; 2389 } 2390 return (0); 2391} 2392 2393 2394/* 2395 * Set the publicly exported filesystem (WebNFS). Currently, only 2396 * one public filesystem is possible in the spec (RFC 2054 and 2055) 2397 */ 2398int 2399vfs_setpublicfs(mp, nep, argp) 2400 struct mount *mp; 2401 struct netexport *nep; 2402 struct export_args *argp; 2403{ 2404 int error; 2405 struct vnode *rvp; 2406 char *cp; 2407 2408 /* 2409 * mp == NULL -> invalidate the current info, the FS is 2410 * no longer exported. May be called from either vfs_export 2411 * or unmount, so check if it hasn't already been done. 2412 */ 2413 if (mp == NULL) { 2414 if (nfs_pub.np_valid) { 2415 nfs_pub.np_valid = 0; 2416 if (nfs_pub.np_index != NULL) { 2417 FREE(nfs_pub.np_index, M_TEMP); 2418 nfs_pub.np_index = NULL; 2419 } 2420 } 2421 return (0); 2422 } 2423 2424 /* 2425 * Only one allowed at a time. 2426 */ 2427 if (nfs_pub.np_valid != 0 && mp != nfs_pub.np_mount) 2428 return (EBUSY); 2429 2430 /* 2431 * Get real filehandle for root of exported FS. 2432 */ 2433 bzero((caddr_t)&nfs_pub.np_handle, sizeof(nfs_pub.np_handle)); 2434 nfs_pub.np_handle.fh_fsid = mp->mnt_stat.f_fsid; 2435 2436 if ((error = VFS_ROOT(mp, &rvp))) 2437 return (error); 2438 2439 if ((error = VFS_VPTOFH(rvp, &nfs_pub.np_handle.fh_fid))) 2440 return (error); 2441 2442 vput(rvp); 2443 2444 /* 2445 * If an indexfile was specified, pull it in. 2446 */ 2447 if (argp->ex_indexfile != NULL) { 2448 MALLOC(nfs_pub.np_index, char *, MAXNAMLEN + 1, M_TEMP, 2449 M_WAITOK); 2450 error = copyinstr(argp->ex_indexfile, nfs_pub.np_index, 2451 MAXNAMLEN, (size_t *)0); 2452 if (!error) { 2453 /* 2454 * Check for illegal filenames. 2455 */ 2456 for (cp = nfs_pub.np_index; *cp; cp++) { 2457 if (*cp == '/') { 2458 error = EINVAL; 2459 break; 2460 } 2461 } 2462 } 2463 if (error) { 2464 FREE(nfs_pub.np_index, M_TEMP); 2465 return (error); 2466 } 2467 } 2468 2469 nfs_pub.np_mount = mp; 2470 nfs_pub.np_valid = 1; 2471 return (0); 2472} 2473 2474struct netcred * 2475vfs_export_lookup(mp, nep, nam) 2476 register struct mount *mp; 2477 struct netexport *nep; 2478 struct sockaddr *nam; 2479{ 2480 register struct netcred *np; 2481 register struct radix_node_head *rnh; 2482 struct sockaddr *saddr; 2483 2484 np = NULL; 2485 if (mp->mnt_flag & MNT_EXPORTED) { 2486 /* 2487 * Lookup in the export list first. 2488 */ 2489 if (nam != NULL) { 2490 saddr = nam; 2491 rnh = nep->ne_rtable[saddr->sa_family]; 2492 if (rnh != NULL) { 2493 np = (struct netcred *) 2494 (*rnh->rnh_matchaddr)((caddr_t)saddr, 2495 rnh); 2496 if (np && np->netc_rnodes->rn_flags & RNF_ROOT) 2497 np = NULL; 2498 } 2499 } 2500 /* 2501 * If no address match, use the default if it exists. 2502 */ 2503 if (np == NULL && mp->mnt_flag & MNT_DEFEXPORTED) 2504 np = &nep->ne_defexported; 2505 } 2506 return (np); 2507} 2508 2509/* 2510 * perform msync on all vnodes under a mount point 2511 * the mount point must be locked. 2512 */ 2513void 2514vfs_msync(struct mount *mp, int flags) { 2515 struct vnode *vp, *nvp; 2516 struct vm_object *obj; 2517 int anyio, tries; 2518 2519 tries = 5; 2520loop: 2521 anyio = 0; 2522 for (vp = mp->mnt_vnodelist.lh_first; vp != NULL; vp = nvp) { 2523 2524 nvp = vp->v_mntvnodes.le_next; 2525 2526 if (vp->v_mount != mp) { 2527 goto loop; 2528 } 2529 2530 if (vp->v_flag & VXLOCK) /* XXX: what if MNT_WAIT? */ 2531 continue; 2532 2533 if (flags != MNT_WAIT) { 2534 obj = vp->v_object; 2535 if (obj == NULL || (obj->flags & OBJ_MIGHTBEDIRTY) == 0) 2536 continue; 2537 if (VOP_ISLOCKED(vp)) 2538 continue; 2539 } 2540 2541 simple_lock(&vp->v_interlock); 2542 if (vp->v_object && 2543 (vp->v_object->flags & OBJ_MIGHTBEDIRTY)) { 2544 if (!vget(vp, 2545 LK_INTERLOCK | LK_EXCLUSIVE | LK_RETRY | LK_NOOBJ, curproc)) { 2546 if (vp->v_object) { 2547 vm_object_page_clean(vp->v_object, 0, 0, flags == MNT_WAIT ? OBJPC_SYNC : 0); 2548 anyio = 1; 2549 } 2550 vput(vp); 2551 } 2552 } else { 2553 simple_unlock(&vp->v_interlock); 2554 } 2555 } 2556 if (anyio && (--tries > 0)) 2557 goto loop; 2558} 2559 2560/* 2561 * Create the VM object needed for VMIO and mmap support. This 2562 * is done for all VREG files in the system. Some filesystems might 2563 * afford the additional metadata buffering capability of the 2564 * VMIO code by making the device node be VMIO mode also. 2565 * 2566 * vp must be locked when vfs_object_create is called. 2567 */ 2568int 2569vfs_object_create(vp, p, cred) 2570 struct vnode *vp; 2571 struct proc *p; 2572 struct ucred *cred; 2573{ 2574 struct vattr vat; 2575 vm_object_t object; 2576 int error = 0; 2577 2578 if ((vp->v_type != VREG) && (vp->v_type != VBLK)) 2579 return 0; 2580 2581retry: 2582 if ((object = vp->v_object) == NULL) { 2583 if (vp->v_type == VREG) { 2584 if ((error = VOP_GETATTR(vp, &vat, cred, p)) != 0) 2585 goto retn; 2586 object = vnode_pager_alloc(vp, vat.va_size, 0, 0); 2587 } else if (major(vp->v_rdev) < nblkdev && 2588 bdevsw(vp->v_rdev) != NULL) { 2589 /* 2590 * This simply allocates the biggest object possible 2591 * for a VBLK vnode. This should be fixed, but doesn't 2592 * cause any problems (yet). 2593 */ 2594 object = vnode_pager_alloc(vp, IDX_TO_OFF(INT_MAX), 0, 0); 2595 } else { 2596 goto retn; 2597 } 2598 /* 2599 * Dereference the reference we just created. This assumes 2600 * that the object is associated with the vp. 2601 */ 2602 object->ref_count--; 2603 vp->v_usecount--; 2604 } else { 2605 if (object->flags & OBJ_DEAD) { 2606 VOP_UNLOCK(vp, 0, p); 2607 tsleep(object, PVM, "vodead", 0); 2608 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p); 2609 goto retry; 2610 } 2611 } 2612 2613 KASSERT(vp->v_object != NULL, ("vfs_object_create: NULL object")); 2614 vp->v_flag |= VOBJBUF; 2615 2616retn: 2617 return error; 2618} 2619 2620static void 2621vfree(vp) 2622 struct vnode *vp; 2623{ 2624 int s; 2625 2626 s = splbio(); 2627 simple_lock(&vnode_free_list_slock); 2628 if (vp->v_flag & VTBFREE) { 2629 TAILQ_REMOVE(&vnode_tobefree_list, vp, v_freelist); 2630 vp->v_flag &= ~VTBFREE; 2631 } 2632 if (vp->v_flag & VAGE) { 2633 TAILQ_INSERT_HEAD(&vnode_free_list, vp, v_freelist); 2634 } else { 2635 TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_freelist); 2636 } 2637 freevnodes++; 2638 simple_unlock(&vnode_free_list_slock); 2639 vp->v_flag &= ~VAGE; 2640 vp->v_flag |= VFREE; 2641 splx(s); 2642} 2643 2644void 2645vbusy(vp) 2646 struct vnode *vp; 2647{ 2648 int s; 2649 2650 s = splbio(); 2651 simple_lock(&vnode_free_list_slock); 2652 if (vp->v_flag & VTBFREE) { 2653 TAILQ_REMOVE(&vnode_tobefree_list, vp, v_freelist); 2654 vp->v_flag &= ~VTBFREE; 2655 } else { 2656 TAILQ_REMOVE(&vnode_free_list, vp, v_freelist); 2657 freevnodes--; 2658 } 2659 simple_unlock(&vnode_free_list_slock); 2660 vp->v_flag &= ~(VFREE|VAGE); 2661 splx(s); 2662} 2663 2664/* 2665 * Record a process's interest in events which might happen to 2666 * a vnode. Because poll uses the historic select-style interface 2667 * internally, this routine serves as both the ``check for any 2668 * pending events'' and the ``record my interest in future events'' 2669 * functions. (These are done together, while the lock is held, 2670 * to avoid race conditions.) 2671 */ 2672int 2673vn_pollrecord(vp, p, events) 2674 struct vnode *vp; 2675 struct proc *p; 2676 short events; 2677{ 2678 simple_lock(&vp->v_pollinfo.vpi_lock); 2679 if (vp->v_pollinfo.vpi_revents & events) { 2680 /* 2681 * This leaves events we are not interested 2682 * in available for the other process which 2683 * which presumably had requested them 2684 * (otherwise they would never have been 2685 * recorded). 2686 */ 2687 events &= vp->v_pollinfo.vpi_revents; 2688 vp->v_pollinfo.vpi_revents &= ~events; 2689 2690 simple_unlock(&vp->v_pollinfo.vpi_lock); 2691 return events; 2692 } 2693 vp->v_pollinfo.vpi_events |= events; 2694 selrecord(p, &vp->v_pollinfo.vpi_selinfo); 2695 simple_unlock(&vp->v_pollinfo.vpi_lock); 2696 return 0; 2697} 2698 2699/* 2700 * Note the occurrence of an event. If the VN_POLLEVENT macro is used, 2701 * it is possible for us to miss an event due to race conditions, but 2702 * that condition is expected to be rare, so for the moment it is the 2703 * preferred interface. 2704 */ 2705void 2706vn_pollevent(vp, events) 2707 struct vnode *vp; 2708 short events; 2709{ 2710 simple_lock(&vp->v_pollinfo.vpi_lock); 2711 if (vp->v_pollinfo.vpi_events & events) { 2712 /* 2713 * We clear vpi_events so that we don't 2714 * call selwakeup() twice if two events are 2715 * posted before the polling process(es) is 2716 * awakened. This also ensures that we take at 2717 * most one selwakeup() if the polling process 2718 * is no longer interested. However, it does 2719 * mean that only one event can be noticed at 2720 * a time. (Perhaps we should only clear those 2721 * event bits which we note?) XXX 2722 */ 2723 vp->v_pollinfo.vpi_events = 0; /* &= ~events ??? */ 2724 vp->v_pollinfo.vpi_revents |= events; 2725 selwakeup(&vp->v_pollinfo.vpi_selinfo); 2726 } 2727 simple_unlock(&vp->v_pollinfo.vpi_lock); 2728} 2729 2730/* 2731 * Wake up anyone polling on vp because it is being revoked. 2732 * This depends on dead_poll() returning POLLHUP for correct 2733 * behavior. 2734 */ 2735void 2736vn_pollgone(vp) 2737 struct vnode *vp; 2738{ 2739 simple_lock(&vp->v_pollinfo.vpi_lock); 2740 if (vp->v_pollinfo.vpi_events) { 2741 vp->v_pollinfo.vpi_events = 0; 2742 selwakeup(&vp->v_pollinfo.vpi_selinfo); 2743 } 2744 simple_unlock(&vp->v_pollinfo.vpi_lock); 2745} 2746 2747 2748 2749/* 2750 * Routine to create and manage a filesystem syncer vnode. 2751 */ 2752#define sync_close ((int (*) __P((struct vop_close_args *)))nullop) 2753static int sync_fsync __P((struct vop_fsync_args *)); 2754static int sync_inactive __P((struct vop_inactive_args *)); 2755static int sync_reclaim __P((struct vop_reclaim_args *)); 2756#define sync_lock ((int (*) __P((struct vop_lock_args *)))vop_nolock) 2757#define sync_unlock ((int (*) __P((struct vop_unlock_args *)))vop_nounlock) 2758static int sync_print __P((struct vop_print_args *)); 2759#define sync_islocked ((int(*) __P((struct vop_islocked_args *)))vop_noislocked) 2760 2761static vop_t **sync_vnodeop_p; 2762static struct vnodeopv_entry_desc sync_vnodeop_entries[] = { 2763 { &vop_default_desc, (vop_t *) vop_eopnotsupp }, 2764 { &vop_close_desc, (vop_t *) sync_close }, /* close */ 2765 { &vop_fsync_desc, (vop_t *) sync_fsync }, /* fsync */ 2766 { &vop_inactive_desc, (vop_t *) sync_inactive }, /* inactive */ 2767 { &vop_reclaim_desc, (vop_t *) sync_reclaim }, /* reclaim */ 2768 { &vop_lock_desc, (vop_t *) sync_lock }, /* lock */ 2769 { &vop_unlock_desc, (vop_t *) sync_unlock }, /* unlock */ 2770 { &vop_print_desc, (vop_t *) sync_print }, /* print */ 2771 { &vop_islocked_desc, (vop_t *) sync_islocked }, /* islocked */ 2772 { NULL, NULL } 2773}; 2774static struct vnodeopv_desc sync_vnodeop_opv_desc = 2775 { &sync_vnodeop_p, sync_vnodeop_entries }; 2776 2777VNODEOP_SET(sync_vnodeop_opv_desc); 2778 2779/* 2780 * Create a new filesystem syncer vnode for the specified mount point. 2781 */ 2782int 2783vfs_allocate_syncvnode(mp) 2784 struct mount *mp; 2785{ 2786 struct vnode *vp; 2787 static long start, incr, next; 2788 int error; 2789 2790 /* Allocate a new vnode */ 2791 if ((error = getnewvnode(VT_VFS, mp, sync_vnodeop_p, &vp)) != 0) { 2792 mp->mnt_syncer = NULL; 2793 return (error); 2794 } 2795 vp->v_type = VNON; 2796 /* 2797 * Place the vnode onto the syncer worklist. We attempt to 2798 * scatter them about on the list so that they will go off 2799 * at evenly distributed times even if all the filesystems 2800 * are mounted at once. 2801 */ 2802 next += incr; 2803 if (next == 0 || next > syncer_maxdelay) { 2804 start /= 2; 2805 incr /= 2; 2806 if (start == 0) { 2807 start = syncer_maxdelay / 2; 2808 incr = syncer_maxdelay; 2809 } 2810 next = start; 2811 } 2812 vn_syncer_add_to_worklist(vp, syncdelay > 0 ? next % syncdelay : 0); 2813 mp->mnt_syncer = vp; 2814 return (0); 2815} 2816 2817/* 2818 * Do a lazy sync of the filesystem. 2819 */ 2820static int 2821sync_fsync(ap) 2822 struct vop_fsync_args /* { 2823 struct vnode *a_vp; 2824 struct ucred *a_cred; 2825 int a_waitfor; 2826 struct proc *a_p; 2827 } */ *ap; 2828{ 2829 struct vnode *syncvp = ap->a_vp; 2830 struct mount *mp = syncvp->v_mount; 2831 struct proc *p = ap->a_p; 2832 int asyncflag; 2833 2834 /* 2835 * We only need to do something if this is a lazy evaluation. 2836 */ 2837 if (ap->a_waitfor != MNT_LAZY) 2838 return (0); 2839 2840 /* 2841 * Move ourselves to the back of the sync list. 2842 */ 2843 vn_syncer_add_to_worklist(syncvp, syncdelay); 2844 2845 /* 2846 * Walk the list of vnodes pushing all that are dirty and 2847 * not already on the sync list. 2848 */ 2849 simple_lock(&mountlist_slock); 2850 if (vfs_busy(mp, LK_EXCLUSIVE | LK_NOWAIT, &mountlist_slock, p) != 0) { 2851 simple_unlock(&mountlist_slock); 2852 return (0); 2853 } 2854 asyncflag = mp->mnt_flag & MNT_ASYNC; 2855 mp->mnt_flag &= ~MNT_ASYNC; 2856 vfs_msync(mp, MNT_NOWAIT); 2857 VFS_SYNC(mp, MNT_LAZY, ap->a_cred, p); 2858 if (asyncflag) 2859 mp->mnt_flag |= MNT_ASYNC; 2860 vfs_unbusy(mp, p); 2861 return (0); 2862} 2863 2864/* 2865 * The syncer vnode is no referenced. 2866 */ 2867static int 2868sync_inactive(ap) 2869 struct vop_inactive_args /* { 2870 struct vnode *a_vp; 2871 struct proc *a_p; 2872 } */ *ap; 2873{ 2874 2875 vgone(ap->a_vp); 2876 return (0); 2877} 2878 2879/* 2880 * The syncer vnode is no longer needed and is being decommissioned. 2881 * 2882 * Modifications to the worklist must be protected at splbio(). 2883 */ 2884static int 2885sync_reclaim(ap) 2886 struct vop_reclaim_args /* { 2887 struct vnode *a_vp; 2888 } */ *ap; 2889{ 2890 struct vnode *vp = ap->a_vp; 2891 int s; 2892 2893 s = splbio(); 2894 vp->v_mount->mnt_syncer = NULL; 2895 if (vp->v_flag & VONWORKLST) { 2896 LIST_REMOVE(vp, v_synclist); 2897 vp->v_flag &= ~VONWORKLST; 2898 } 2899 splx(s); 2900 2901 return (0); 2902} 2903 2904/* 2905 * Print out a syncer vnode. 2906 */ 2907static int 2908sync_print(ap) 2909 struct vop_print_args /* { 2910 struct vnode *a_vp; 2911 } */ *ap; 2912{ 2913 struct vnode *vp = ap->a_vp; 2914 2915 printf("syncer vnode"); 2916 if (vp->v_vnlock != NULL) 2917 lockmgr_printinfo(vp->v_vnlock); 2918 printf("\n"); 2919 return (0); 2920} 2921