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 1.201 1999/06/15 23:37:25 mckusick 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 80 static MALLOC_DEFINE(M_NETADDR, "Export Host", "Export host address structure"); 81 82 static void insmntque __P((struct vnode *vp, struct mount *mp)); 83 static void vclean __P((struct vnode *vp, int flags, struct proc *p)); 84 static void vfree __P((struct vnode *)); 85 static void vgonel __P((struct vnode *vp, struct proc *p)); 86 static unsigned long numvnodes; 87 SYSCTL_INT(_debug, OID_AUTO, numvnodes, CTLFLAG_RD, &numvnodes, 0, ""); 88 89 enum vtype iftovt_tab[16] = { 90 VNON, VFIFO, VCHR, VNON, VDIR, VNON, VBLK, VNON, 91 VREG, VNON, VLNK, VNON, VSOCK, VNON, VNON, VBAD, 92 }; 93 int vttoif_tab[9] = { 94 0, S_IFREG, S_IFDIR, S_IFBLK, S_IFCHR, S_IFLNK, 95 S_IFSOCK, S_IFIFO, S_IFMT, 96 }; 97 98 static TAILQ_HEAD(freelst, vnode) vnode_free_list; /* vnode free list */ 99 struct tobefreelist vnode_tobefree_list; /* vnode free list */ 100 101 static u_long wantfreevnodes = 25; 102 SYSCTL_INT(_debug, OID_AUTO, wantfreevnodes, CTLFLAG_RW, &wantfreevnodes, 0, ""); 103 static u_long freevnodes = 0; 104 SYSCTL_INT(_debug, OID_AUTO, freevnodes, CTLFLAG_RD, &freevnodes, 0, ""); 105 106 int vfs_ioopt = 0; 107 #ifdef ENABLE_VFS_IOOPT 108 SYSCTL_INT(_vfs, OID_AUTO, ioopt, CTLFLAG_RW, &vfs_ioopt, 0, ""); 109 #endif 110 111 struct mntlist mountlist; /* mounted filesystem list */ 112 struct simplelock mountlist_slock; 113 struct simplelock mntvnode_slock; 114 int nfs_mount_type = -1; 115 #ifndef NULL_SIMPLELOCKS 116 static struct simplelock mntid_slock; 117 static struct simplelock vnode_free_list_slock; 118 static struct simplelock spechash_slock; 119 #endif 120 struct nfs_public nfs_pub; /* publicly exported FS */ 121 static vm_zone_t vnode_zone; 122 123 /* 124 * The workitem queue. 125 */ 126 #define SYNCER_MAXDELAY 32 127 static int syncer_maxdelay = SYNCER_MAXDELAY; /* maximum delay time */ 128 time_t syncdelay = 30; /* max time to delay syncing data */ 129 time_t filedelay = 30; /* time to delay syncing files */ 130 SYSCTL_INT(_kern, OID_AUTO, filedelay, CTLFLAG_RW, &filedelay, 0, ""); 131 time_t dirdelay = 15; /* time to delay syncing directories */ 132 SYSCTL_INT(_kern, OID_AUTO, dirdelay, CTLFLAG_RW, &dirdelay, 0, ""); 133 time_t metadelay = 10; /* time to delay syncing metadata */ 134 SYSCTL_INT(_kern, OID_AUTO, metadelay, CTLFLAG_RW, &metadelay, 0, ""); 135 static int rushjob; /* number of slots to run ASAP */ 136 static int stat_rush_requests; /* number of times I/O speeded up */ 137 SYSCTL_INT(_debug, OID_AUTO, rush_requests, CTLFLAG_RW, &stat_rush_requests, 0, ""); 138 139 static int syncer_delayno = 0; 140 static long syncer_mask; 141 LIST_HEAD(synclist, vnode); 142 static struct synclist *syncer_workitem_pending; 143 144 int desiredvnodes; 145 SYSCTL_INT(_kern, KERN_MAXVNODES, maxvnodes, CTLFLAG_RW, 146 &desiredvnodes, 0, "Maximum number of vnodes"); 147 148 static void vfs_free_addrlist __P((struct netexport *nep)); 149 static int vfs_free_netcred __P((struct radix_node *rn, void *w)); 150 static int vfs_hang_addrlist __P((struct mount *mp, struct netexport *nep, 151 struct export_args *argp)); 152 153 /* 154 * Initialize the vnode management data structures. 155 */ 156 void 157 vntblinit() 158 { 159 160 desiredvnodes = maxproc + cnt.v_page_count / 4; 161 simple_lock_init(&mntvnode_slock); 162 simple_lock_init(&mntid_slock); 163 simple_lock_init(&spechash_slock); 164 TAILQ_INIT(&vnode_free_list); 165 TAILQ_INIT(&vnode_tobefree_list); 166 simple_lock_init(&vnode_free_list_slock); 167 CIRCLEQ_INIT(&mountlist); 168 vnode_zone = zinit("VNODE", sizeof (struct vnode), 0, 0, 5); 169 /* 170 * Initialize the filesystem syncer. 171 */ 172 syncer_workitem_pending = hashinit(syncer_maxdelay, M_VNODE, 173 &syncer_mask); 174 syncer_maxdelay = syncer_mask + 1; 175 } 176 177 /* 178 * Mark a mount point as busy. Used to synchronize access and to delay 179 * unmounting. Interlock is not released on failure. 180 */ 181 int 182 vfs_busy(mp, flags, interlkp, p) 183 struct mount *mp; 184 int flags; 185 struct simplelock *interlkp; 186 struct proc *p; 187 { 188 int lkflags; 189 190 if (mp->mnt_kern_flag & MNTK_UNMOUNT) { 191 if (flags & LK_NOWAIT) 192 return (ENOENT); 193 mp->mnt_kern_flag |= MNTK_MWAIT; 194 if (interlkp) { 195 simple_unlock(interlkp); 196 } 197 /* 198 * Since all busy locks are shared except the exclusive 199 * lock granted when unmounting, the only place that a 200 * wakeup needs to be done is at the release of the 201 * exclusive lock at the end of dounmount. 202 */ 203 tsleep((caddr_t)mp, PVFS, "vfs_busy", 0); 204 if (interlkp) { 205 simple_lock(interlkp); 206 } 207 return (ENOENT); 208 } 209 lkflags = LK_SHARED | LK_NOPAUSE; 210 if (interlkp) 211 lkflags |= LK_INTERLOCK; 212 if (lockmgr(&mp->mnt_lock, lkflags, interlkp, p)) 213 panic("vfs_busy: unexpected lock failure"); 214 return (0); 215 } 216 217 /* 218 * Free a busy filesystem. 219 */ 220 void 221 vfs_unbusy(mp, p) 222 struct mount *mp; 223 struct proc *p; 224 { 225 226 lockmgr(&mp->mnt_lock, LK_RELEASE, NULL, p); 227 } 228 229 /* 230 * Lookup a filesystem type, and if found allocate and initialize 231 * a mount structure for it. 232 * 233 * Devname is usually updated by mount(8) after booting. 234 */ 235 int 236 vfs_rootmountalloc(fstypename, devname, mpp) 237 char *fstypename; 238 char *devname; 239 struct mount **mpp; 240 { 241 struct proc *p = curproc; /* XXX */ 242 struct vfsconf *vfsp; 243 struct mount *mp; 244 245 if (fstypename == NULL) 246 return (ENODEV); 247 for (vfsp = vfsconf; vfsp; vfsp = vfsp->vfc_next) 248 if (!strcmp(vfsp->vfc_name, fstypename)) 249 break; 250 if (vfsp == NULL) 251 return (ENODEV); 252 mp = malloc((u_long)sizeof(struct mount), M_MOUNT, M_WAITOK); 253 bzero((char *)mp, (u_long)sizeof(struct mount)); 254 lockinit(&mp->mnt_lock, PVFS, "vfslock", 0, LK_NOPAUSE); 255 (void)vfs_busy(mp, LK_NOWAIT, 0, p); 256 LIST_INIT(&mp->mnt_vnodelist); 257 mp->mnt_vfc = vfsp; 258 mp->mnt_op = vfsp->vfc_vfsops; 259 mp->mnt_flag = MNT_RDONLY; 260 mp->mnt_vnodecovered = NULLVP; 261 vfsp->vfc_refcount++; 262 mp->mnt_stat.f_type = vfsp->vfc_typenum; 263 mp->mnt_flag |= vfsp->vfc_flags & MNT_VISFLAGMASK; 264 strncpy(mp->mnt_stat.f_fstypename, vfsp->vfc_name, MFSNAMELEN); 265 mp->mnt_stat.f_mntonname[0] = '/'; 266 mp->mnt_stat.f_mntonname[1] = 0; 267 (void) copystr(devname, mp->mnt_stat.f_mntfromname, MNAMELEN - 1, 0); 268 *mpp = mp; 269 return (0); 270 } 271 272 /* 273 * Find an appropriate filesystem to use for the root. If a filesystem 274 * has not been preselected, walk through the list of known filesystems 275 * trying those that have mountroot routines, and try them until one 276 * works or we have tried them all. 277 */ 278 #ifdef notdef /* XXX JH */ 279 int 280 lite2_vfs_mountroot() 281 { 282 struct vfsconf *vfsp; 283 extern int (*lite2_mountroot) __P((void)); 284 int error; 285 286 if (lite2_mountroot != NULL) 287 return ((*lite2_mountroot)()); 288 for (vfsp = vfsconf; vfsp; vfsp = vfsp->vfc_next) { 289 if (vfsp->vfc_mountroot == NULL) 290 continue; 291 if ((error = (*vfsp->vfc_mountroot)()) == 0) 292 return (0); 293 printf("%s_mountroot failed: %d\n", vfsp->vfc_name, error); 294 } 295 return (ENODEV); 296 } 297 #endif 298 299 /* 300 * Lookup a mount point by filesystem identifier. 301 */ 302 struct mount * 303 vfs_getvfs(fsid) 304 fsid_t *fsid; 305 { 306 register struct mount *mp; 307 308 simple_lock(&mountlist_slock); 309 for (mp = mountlist.cqh_first; mp != (void *)&mountlist; 310 mp = mp->mnt_list.cqe_next) { 311 if (mp->mnt_stat.f_fsid.val[0] == fsid->val[0] && 312 mp->mnt_stat.f_fsid.val[1] == fsid->val[1]) { 313 simple_unlock(&mountlist_slock); 314 return (mp); 315 } 316 } 317 simple_unlock(&mountlist_slock); 318 return ((struct mount *) 0); 319 } 320 321 /* 322 * Get a new unique fsid 323 */ 324 void 325 vfs_getnewfsid(mp) 326 struct mount *mp; 327 { 328 static u_short xxxfs_mntid; 329 330 fsid_t tfsid; 331 int mtype; 332 333 simple_lock(&mntid_slock); 334 mtype = mp->mnt_vfc->vfc_typenum; 335 mp->mnt_stat.f_fsid.val[0] = (256 + mtype) * 256; 336 mp->mnt_stat.f_fsid.val[1] = mtype; 337 if (xxxfs_mntid == 0) 338 ++xxxfs_mntid; 339 tfsid.val[0] = (256 + mtype) * 256 | xxxfs_mntid; 340 tfsid.val[1] = mtype; 341 if (mountlist.cqh_first != (void *)&mountlist) { 342 while (vfs_getvfs(&tfsid)) { 343 tfsid.val[0]++; 344 xxxfs_mntid++; 345 } 346 } 347 mp->mnt_stat.f_fsid.val[0] = tfsid.val[0]; 348 simple_unlock(&mntid_slock); 349 } 350 351 /* 352 * Set vnode attributes to VNOVAL 353 */ 354 void 355 vattr_null(vap) 356 register struct vattr *vap; 357 { 358 359 vap->va_type = VNON; 360 vap->va_size = VNOVAL; 361 vap->va_bytes = VNOVAL; 362 vap->va_mode = VNOVAL; 363 vap->va_nlink = VNOVAL; 364 vap->va_uid = VNOVAL; 365 vap->va_gid = VNOVAL; 366 vap->va_fsid = VNOVAL; 367 vap->va_fileid = VNOVAL; 368 vap->va_blocksize = VNOVAL; 369 vap->va_rdev = VNOVAL; 370 vap->va_atime.tv_sec = VNOVAL; 371 vap->va_atime.tv_nsec = VNOVAL; 372 vap->va_mtime.tv_sec = VNOVAL; 373 vap->va_mtime.tv_nsec = VNOVAL; 374 vap->va_ctime.tv_sec = VNOVAL; 375 vap->va_ctime.tv_nsec = VNOVAL; 376 vap->va_flags = VNOVAL; 377 vap->va_gen = VNOVAL; 378 vap->va_vaflags = 0; 379 } 380 381 /* 382 * Routines having to do with the management of the vnode table. 383 */ 384 extern vop_t **dead_vnodeop_p; 385 386 /* 387 * Return the next vnode from the free list. 388 */ 389 int 390 getnewvnode(tag, mp, vops, vpp) 391 enum vtagtype tag; 392 struct mount *mp; 393 vop_t **vops; 394 struct vnode **vpp; 395 { 396 int s; 397 struct proc *p = curproc; /* XXX */ 398 struct vnode *vp, *tvp, *nvp; 399 vm_object_t object; 400 TAILQ_HEAD(freelst, vnode) vnode_tmp_list; 401 402 /* 403 * We take the least recently used vnode from the freelist 404 * if we can get it and it has no cached pages, and no 405 * namecache entries are relative to it. 406 * Otherwise we allocate a new vnode 407 */ 408 409 s = splbio(); 410 simple_lock(&vnode_free_list_slock); 411 TAILQ_INIT(&vnode_tmp_list); 412 413 for (vp = TAILQ_FIRST(&vnode_tobefree_list); vp; vp = nvp) { 414 nvp = TAILQ_NEXT(vp, v_freelist); 415 TAILQ_REMOVE(&vnode_tobefree_list, vp, v_freelist); 416 if (vp->v_flag & VAGE) { 417 TAILQ_INSERT_HEAD(&vnode_free_list, vp, v_freelist); 418 } else { 419 TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_freelist); 420 } 421 vp->v_flag &= ~(VTBFREE|VAGE); 422 vp->v_flag |= VFREE; 423 if (vp->v_usecount) 424 panic("tobe free vnode isn't"); 425 freevnodes++; 426 } 427 428 if (wantfreevnodes && freevnodes < wantfreevnodes) { 429 vp = NULL; 430 } else if (!wantfreevnodes && freevnodes <= desiredvnodes) { 431 /* 432 * XXX: this is only here to be backwards compatible 433 */ 434 vp = NULL; 435 } else { 436 for (vp = TAILQ_FIRST(&vnode_free_list); vp; vp = nvp) { 437 nvp = TAILQ_NEXT(vp, v_freelist); 438 if (!simple_lock_try(&vp->v_interlock)) 439 continue; 440 if (vp->v_usecount) 441 panic("free vnode isn't"); 442 443 object = vp->v_object; 444 if (object && (object->resident_page_count || object->ref_count)) { 445 printf("object inconsistant state: RPC: %d, RC: %d\n", 446 object->resident_page_count, object->ref_count); 447 /* Don't recycle if it's caching some pages */ 448 TAILQ_REMOVE(&vnode_free_list, vp, v_freelist); 449 TAILQ_INSERT_TAIL(&vnode_tmp_list, vp, v_freelist); 450 continue; 451 } else if (LIST_FIRST(&vp->v_cache_src)) { 452 /* Don't recycle if active in the namecache */ 453 simple_unlock(&vp->v_interlock); 454 continue; 455 } else { 456 break; 457 } 458 } 459 } 460 461 for (tvp = TAILQ_FIRST(&vnode_tmp_list); tvp; tvp = nvp) { 462 nvp = TAILQ_NEXT(tvp, v_freelist); 463 TAILQ_REMOVE(&vnode_tmp_list, tvp, v_freelist); 464 TAILQ_INSERT_TAIL(&vnode_free_list, tvp, v_freelist); 465 simple_unlock(&tvp->v_interlock); 466 } 467 468 if (vp) { 469 vp->v_flag |= VDOOMED; 470 TAILQ_REMOVE(&vnode_free_list, vp, v_freelist); 471 freevnodes--; 472 simple_unlock(&vnode_free_list_slock); 473 cache_purge(vp); 474 vp->v_lease = NULL; 475 if (vp->v_type != VBAD) { 476 vgonel(vp, p); 477 } else { 478 simple_unlock(&vp->v_interlock); 479 } 480 481 #ifdef INVARIANTS 482 { 483 int s; 484 485 if (vp->v_data) 486 panic("cleaned vnode isn't"); 487 s = splbio(); 488 if (vp->v_numoutput) 489 panic("Clean vnode has pending I/O's"); 490 splx(s); 491 } 492 #endif 493 vp->v_flag = 0; 494 vp->v_lastr = 0; 495 vp->v_lastw = 0; 496 vp->v_lasta = 0; 497 vp->v_cstart = 0; 498 vp->v_clen = 0; 499 vp->v_socket = 0; 500 vp->v_writecount = 0; /* XXX */ 501 vp->v_maxio = 0; 502 } else { 503 simple_unlock(&vnode_free_list_slock); 504 vp = (struct vnode *) zalloc(vnode_zone); 505 bzero((char *) vp, sizeof *vp); 506 simple_lock_init(&vp->v_interlock); 507 vp->v_dd = vp; 508 cache_purge(vp); 509 LIST_INIT(&vp->v_cache_src); 510 TAILQ_INIT(&vp->v_cache_dst); 511 numvnodes++; 512 } 513 514 TAILQ_INIT(&vp->v_cleanblkhd); 515 TAILQ_INIT(&vp->v_dirtyblkhd); 516 vp->v_type = VNON; 517 vp->v_tag = tag; 518 vp->v_op = vops; 519 insmntque(vp, mp); 520 *vpp = vp; 521 vp->v_usecount = 1; 522 vp->v_data = 0; 523 splx(s); 524 525 vfs_object_create(vp, p, p->p_ucred); 526 return (0); 527 } 528 529 /* 530 * Move a vnode from one mount queue to another. 531 */ 532 static void 533 insmntque(vp, mp) 534 register struct vnode *vp; 535 register struct mount *mp; 536 { 537 538 simple_lock(&mntvnode_slock); 539 /* 540 * Delete from old mount point vnode list, if on one. 541 */ 542 if (vp->v_mount != NULL) 543 LIST_REMOVE(vp, v_mntvnodes); 544 /* 545 * Insert into list of vnodes for the new mount point, if available. 546 */ 547 if ((vp->v_mount = mp) == NULL) { 548 simple_unlock(&mntvnode_slock); 549 return; 550 } 551 LIST_INSERT_HEAD(&mp->mnt_vnodelist, vp, v_mntvnodes); 552 simple_unlock(&mntvnode_slock); 553 } 554 555 /* 556 * Update outstanding I/O count and do wakeup if requested. 557 */ 558 void 559 vwakeup(bp) 560 register struct buf *bp; 561 { 562 register struct vnode *vp; 563 564 bp->b_flags &= ~B_WRITEINPROG; 565 if ((vp = bp->b_vp)) { 566 vp->v_numoutput--; 567 if (vp->v_numoutput < 0) 568 panic("vwakeup: neg numoutput"); 569 if ((vp->v_numoutput == 0) && (vp->v_flag & VBWAIT)) { 570 vp->v_flag &= ~VBWAIT; 571 wakeup((caddr_t) &vp->v_numoutput); 572 } 573 } 574 } 575 576 /* 577 * Flush out and invalidate all buffers associated with a vnode. 578 * Called with the underlying object locked. 579 */ 580 int 581 vinvalbuf(vp, flags, cred, p, slpflag, slptimeo) 582 register struct vnode *vp; 583 int flags; 584 struct ucred *cred; 585 struct proc *p; 586 int slpflag, slptimeo; 587 { 588 register struct buf *bp; 589 struct buf *nbp, *blist; 590 int s, error; 591 vm_object_t object; 592 593 if (flags & V_SAVE) { 594 s = splbio(); 595 while (vp->v_numoutput) { 596 vp->v_flag |= VBWAIT; 597 error = tsleep((caddr_t)&vp->v_numoutput, 598 slpflag | (PRIBIO + 1), "vinvlbuf", slptimeo); 599 if (error) { 600 splx(s); 601 return (error); 602 } 603 } 604 if (!TAILQ_EMPTY(&vp->v_dirtyblkhd)) { 605 splx(s); 606 if ((error = VOP_FSYNC(vp, cred, MNT_WAIT, p)) != 0) 607 return (error); 608 s = splbio(); 609 if (vp->v_numoutput > 0 || 610 !TAILQ_EMPTY(&vp->v_dirtyblkhd)) 611 panic("vinvalbuf: dirty bufs"); 612 } 613 splx(s); 614 } 615 s = splbio(); 616 for (;;) { 617 blist = TAILQ_FIRST(&vp->v_cleanblkhd); 618 if (!blist) 619 blist = TAILQ_FIRST(&vp->v_dirtyblkhd); 620 if (!blist) 621 break; 622 623 for (bp = blist; bp; bp = nbp) { 624 nbp = TAILQ_NEXT(bp, b_vnbufs); 625 if (bp->b_flags & B_BUSY) { 626 bp->b_flags |= B_WANTED; 627 error = tsleep((caddr_t) bp, 628 slpflag | (PRIBIO + 4), "vinvalbuf", 629 slptimeo); 630 if (error) { 631 splx(s); 632 return (error); 633 } 634 break; 635 } 636 /* 637 * XXX Since there are no node locks for NFS, I 638 * believe there is a slight chance that a delayed 639 * write will occur while sleeping just above, so 640 * check for it. Note that vfs_bio_awrite expects 641 * buffers to reside on a queue, while VOP_BWRITE and 642 * brelse do not. 643 */ 644 if (((bp->b_flags & (B_DELWRI | B_INVAL)) == B_DELWRI) && 645 (flags & V_SAVE)) { 646 647 if (bp->b_vp == vp) { 648 if (bp->b_flags & B_CLUSTEROK) { 649 vfs_bio_awrite(bp); 650 } else { 651 bremfree(bp); 652 bp->b_flags |= (B_BUSY | B_ASYNC); 653 VOP_BWRITE(bp->b_vp, bp); 654 } 655 } else { 656 bremfree(bp); 657 bp->b_flags |= B_BUSY; 658 (void) VOP_BWRITE(bp->b_vp, bp); 659 } 660 break; 661 } 662 bremfree(bp); 663 bp->b_flags |= (B_INVAL | B_NOCACHE | B_RELBUF | B_BUSY); 664 bp->b_flags &= ~B_ASYNC; 665 brelse(bp); 666 } 667 } 668 669 while (vp->v_numoutput > 0) { 670 vp->v_flag |= VBWAIT; 671 tsleep(&vp->v_numoutput, PVM, "vnvlbv", 0); 672 } 673 674 splx(s); 675 676 /* 677 * Destroy the copy in the VM cache, too. 678 */ 679 simple_lock(&vp->v_interlock); 680 object = vp->v_object; 681 if (object != NULL) { 682 vm_object_page_remove(object, 0, 0, 683 (flags & V_SAVE) ? TRUE : FALSE); 684 } 685 simple_unlock(&vp->v_interlock); 686 687 if (!TAILQ_EMPTY(&vp->v_dirtyblkhd) || !TAILQ_EMPTY(&vp->v_cleanblkhd)) 688 panic("vinvalbuf: flush failed"); 689 return (0); 690 } 691 692 /* 693 * Truncate a file's buffer and pages to a specified length. This 694 * is in lieu of the old vinvalbuf mechanism, which performed unneeded 695 * sync activity. 696 */ 697 int 698 vtruncbuf(vp, cred, p, length, blksize) 699 register struct vnode *vp; 700 struct ucred *cred; 701 struct proc *p; 702 off_t length; 703 int blksize; 704 { 705 register struct buf *bp; 706 struct buf *nbp; 707 int s, anyfreed; 708 int trunclbn; 709 710 /* 711 * Round up to the *next* lbn. 712 */ 713 trunclbn = (length + blksize - 1) / blksize; 714 715 s = splbio(); 716 restart: 717 anyfreed = 1; 718 for (;anyfreed;) { 719 anyfreed = 0; 720 for (bp = TAILQ_FIRST(&vp->v_cleanblkhd); bp; bp = nbp) { 721 nbp = TAILQ_NEXT(bp, b_vnbufs); 722 if (bp->b_lblkno >= trunclbn) { 723 if (bp->b_flags & B_BUSY) { 724 bp->b_flags |= B_WANTED; 725 tsleep(bp, PRIBIO + 4, "vtrb1", 0); 726 goto restart; 727 } else { 728 bremfree(bp); 729 bp->b_flags |= (B_BUSY | B_INVAL | B_RELBUF); 730 bp->b_flags &= ~B_ASYNC; 731 brelse(bp); 732 anyfreed = 1; 733 } 734 if (nbp && (((nbp->b_xflags & B_VNCLEAN) == 0)|| 735 (nbp->b_vp != vp) || 736 (nbp->b_flags & B_DELWRI))) { 737 goto restart; 738 } 739 } 740 } 741 742 for (bp = TAILQ_FIRST(&vp->v_dirtyblkhd); bp; bp = nbp) { 743 nbp = TAILQ_NEXT(bp, b_vnbufs); 744 if (bp->b_lblkno >= trunclbn) { 745 if (bp->b_flags & B_BUSY) { 746 bp->b_flags |= B_WANTED; 747 tsleep(bp, PRIBIO + 4, "vtrb2", 0); 748 goto restart; 749 } else { 750 bremfree(bp); 751 bp->b_flags |= (B_BUSY | B_INVAL | B_RELBUF); 752 bp->b_flags &= ~B_ASYNC; 753 brelse(bp); 754 anyfreed = 1; 755 } 756 if (nbp && (((nbp->b_xflags & B_VNDIRTY) == 0)|| 757 (nbp->b_vp != vp) || 758 (nbp->b_flags & B_DELWRI) == 0)) { 759 goto restart; 760 } 761 } 762 } 763 } 764 765 if (length > 0) { 766 restartsync: 767 for (bp = TAILQ_FIRST(&vp->v_dirtyblkhd); bp; bp = nbp) { 768 nbp = TAILQ_NEXT(bp, b_vnbufs); 769 if ((bp->b_flags & B_DELWRI) && (bp->b_lblkno < 0)) { 770 if (bp->b_flags & B_BUSY) { 771 bp->b_flags |= B_WANTED; 772 tsleep(bp, PRIBIO, "vtrb3", 0); 773 } else { 774 bremfree(bp); 775 bp->b_flags |= B_BUSY; 776 if (bp->b_vp == vp) { 777 bp->b_flags |= B_ASYNC; 778 } else { 779 bp->b_flags &= ~B_ASYNC; 780 } 781 VOP_BWRITE(bp->b_vp, bp); 782 } 783 goto restartsync; 784 } 785 786 } 787 } 788 789 while (vp->v_numoutput > 0) { 790 vp->v_flag |= VBWAIT; 791 tsleep(&vp->v_numoutput, PVM, "vbtrunc", 0); 792 } 793 794 splx(s); 795 796 vnode_pager_setsize(vp, length); 797 798 return (0); 799 } 800 801 /* 802 * Associate a buffer with a vnode. 803 */ 804 void 805 bgetvp(vp, bp) 806 register struct vnode *vp; 807 register struct buf *bp; 808 { 809 int s; 810 811 KASSERT(bp->b_vp == NULL, ("bgetvp: not free")); 812 813 vhold(vp); 814 bp->b_vp = vp; 815 if (vp->v_type == VBLK || vp->v_type == VCHR) 816 bp->b_dev = vp->v_rdev; 817 else 818 bp->b_dev = NODEV; 819 /* 820 * Insert onto list for new vnode. 821 */ 822 s = splbio(); 823 bp->b_xflags |= B_VNCLEAN; 824 bp->b_xflags &= ~B_VNDIRTY; 825 TAILQ_INSERT_TAIL(&vp->v_cleanblkhd, bp, b_vnbufs); 826 splx(s); 827 } 828 829 /* 830 * Disassociate a buffer from a vnode. 831 */ 832 void 833 brelvp(bp) 834 register struct buf *bp; 835 { 836 struct vnode *vp; 837 struct buflists *listheadp; 838 int s; 839 840 KASSERT(bp->b_vp != NULL, ("brelvp: NULL")); 841 842 /* 843 * Delete from old vnode list, if on one. 844 */ 845 vp = bp->b_vp; 846 s = splbio(); 847 if (bp->b_xflags & (B_VNDIRTY|B_VNCLEAN)) { 848 if (bp->b_xflags & B_VNDIRTY) 849 listheadp = &vp->v_dirtyblkhd; 850 else 851 listheadp = &vp->v_cleanblkhd; 852 TAILQ_REMOVE(listheadp, bp, b_vnbufs); 853 bp->b_xflags &= ~(B_VNDIRTY|B_VNCLEAN); 854 } 855 if ((vp->v_flag & VONWORKLST) && TAILQ_EMPTY(&vp->v_dirtyblkhd)) { 856 vp->v_flag &= ~VONWORKLST; 857 LIST_REMOVE(vp, v_synclist); 858 } 859 splx(s); 860 bp->b_vp = (struct vnode *) 0; 861 vdrop(vp); 862 } 863 864 /* 865 * The workitem queue. 866 * 867 * It is useful to delay writes of file data and filesystem metadata 868 * for tens of seconds so that quickly created and deleted files need 869 * not waste disk bandwidth being created and removed. To realize this, 870 * we append vnodes to a "workitem" queue. When running with a soft 871 * updates implementation, most pending metadata dependencies should 872 * not wait for more than a few seconds. Thus, mounted on block devices 873 * are delayed only about a half the time that file data is delayed. 874 * Similarly, directory updates are more critical, so are only delayed 875 * about a third the time that file data is delayed. Thus, there are 876 * SYNCER_MAXDELAY queues that are processed round-robin at a rate of 877 * one each second (driven off the filesystem syner process). The 878 * syncer_delayno variable indicates the next queue that is to be processed. 879 * Items that need to be processed soon are placed in this queue: 880 * 881 * syncer_workitem_pending[syncer_delayno] 882 * 883 * A delay of fifteen seconds is done by placing the request fifteen 884 * entries later in the queue: 885 * 886 * syncer_workitem_pending[(syncer_delayno + 15) & syncer_mask] 887 * 888 */ 889 890 /* 891 * Add an item to the syncer work queue. 892 */ 893 static void 894 vn_syncer_add_to_worklist(struct vnode *vp, int delay) 895 { 896 int s, slot; 897 898 s = splbio(); 899 900 if (vp->v_flag & VONWORKLST) { 901 LIST_REMOVE(vp, v_synclist); 902 } 903 904 if (delay > syncer_maxdelay - 2) 905 delay = syncer_maxdelay - 2; 906 slot = (syncer_delayno + delay) & syncer_mask; 907 908 LIST_INSERT_HEAD(&syncer_workitem_pending[slot], vp, v_synclist); 909 vp->v_flag |= VONWORKLST; 910 splx(s); 911 } 912 913 struct proc *updateproc; 914 static void sched_sync __P((void)); 915 static const struct kproc_desc up_kp = { 916 "syncer", 917 sched_sync, 918 &updateproc 919 }; 920 SYSINIT_KT(syncer, SI_SUB_KTHREAD_UPDATE, SI_ORDER_FIRST, kproc_start, &up_kp) 921 922 /* 923 * System filesystem synchronizer daemon. 924 */ 925 void 926 sched_sync(void) 927 { 928 struct synclist *slp; 929 struct vnode *vp; 930 long starttime; 931 int s; 932 struct proc *p = updateproc; 933 934 for (;;) { 935 starttime = time_second; 936 937 /* 938 * Push files whose dirty time has expired. Be careful 939 * of interrupt race on slp queue. 940 */ 941 s = splbio(); 942 slp = &syncer_workitem_pending[syncer_delayno]; 943 syncer_delayno += 1; 944 if (syncer_delayno == syncer_maxdelay) 945 syncer_delayno = 0; 946 splx(s); 947 948 while ((vp = LIST_FIRST(slp)) != NULL) { 949 if (VOP_ISLOCKED(vp) == 0) { 950 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p); 951 (void) VOP_FSYNC(vp, p->p_ucred, MNT_LAZY, p); 952 VOP_UNLOCK(vp, 0, p); 953 } 954 s = splbio(); 955 if (LIST_FIRST(slp) == vp) { 956 /* 957 * Note: v_tag VT_VFS vps can remain on the 958 * worklist too with no dirty blocks, but 959 * since sync_fsync() moves it to a different 960 * slot we are safe. 961 */ 962 if (TAILQ_EMPTY(&vp->v_dirtyblkhd) && 963 vp->v_type != VBLK) 964 panic("sched_sync: fsync failed vp %p tag %d", vp, vp->v_tag); 965 /* 966 * Put us back on the worklist. The worklist 967 * routine will remove us from our current 968 * position and then add us back in at a later 969 * position. 970 */ 971 vn_syncer_add_to_worklist(vp, syncdelay); 972 } 973 splx(s); 974 } 975 976 /* 977 * Do soft update processing. 978 */ 979 if (bioops.io_sync) 980 (*bioops.io_sync)(NULL); 981 982 /* 983 * The variable rushjob allows the kernel to speed up the 984 * processing of the filesystem syncer process. A rushjob 985 * value of N tells the filesystem syncer to process the next 986 * N seconds worth of work on its queue ASAP. Currently rushjob 987 * is used by the soft update code to speed up the filesystem 988 * syncer process when the incore state is getting so far 989 * ahead of the disk that the kernel memory pool is being 990 * threatened with exhaustion. 991 */ 992 if (rushjob > 0) { 993 rushjob -= 1; 994 continue; 995 } 996 /* 997 * If it has taken us less than a second to process the 998 * current work, then wait. Otherwise start right over 999 * again. We can still lose time if any single round 1000 * takes more than two seconds, but it does not really 1001 * matter as we are just trying to generally pace the 1002 * filesystem activity. 1003 */ 1004 if (time_second == starttime) 1005 tsleep(&lbolt, PPAUSE, "syncer", 0); 1006 } 1007 } 1008 1009 /* 1010 * Request the syncer daemon to speed up its work. 1011 * We never push it to speed up more than half of its 1012 * normal turn time, otherwise it could take over the cpu. 1013 */ 1014 int 1015 speedup_syncer() 1016 { 1017 int s; 1018 1019 s = splhigh(); 1020 if (updateproc->p_wchan == &lbolt) 1021 setrunnable(updateproc); 1022 splx(s); 1023 if (rushjob < syncdelay / 2) { 1024 rushjob += 1; 1025 stat_rush_requests += 1; 1026 return (1); 1027 } 1028 return(0); 1029 } 1030 1031 /* 1032 * Associate a p-buffer with a vnode. 1033 * 1034 * Also sets B_PAGING flag to indicate that vnode is not fully associated 1035 * with the buffer. i.e. the bp has not been linked into the vnode or 1036 * ref-counted. 1037 */ 1038 void 1039 pbgetvp(vp, bp) 1040 register struct vnode *vp; 1041 register struct buf *bp; 1042 { 1043 1044 KASSERT(bp->b_vp == NULL, ("pbgetvp: not free")); 1045 1046 bp->b_vp = vp; 1047 bp->b_flags |= B_PAGING; 1048 if (vp->v_type == VBLK || vp->v_type == VCHR) 1049 bp->b_dev = vp->v_rdev; 1050 else 1051 bp->b_dev = NODEV; 1052 } 1053 1054 /* 1055 * Disassociate a p-buffer from a vnode. 1056 */ 1057 void 1058 pbrelvp(bp) 1059 register struct buf *bp; 1060 { 1061 1062 KASSERT(bp->b_vp != NULL, ("pbrelvp: NULL")); 1063 1064 #if !defined(MAX_PERF) 1065 /* XXX REMOVE ME */ 1066 if (bp->b_vnbufs.tqe_next != NULL) { 1067 panic( 1068 "relpbuf(): b_vp was probably reassignbuf()d %p %x", 1069 bp, 1070 (int)bp->b_flags 1071 ); 1072 } 1073 #endif 1074 bp->b_vp = (struct vnode *) 0; 1075 bp->b_flags &= ~B_PAGING; 1076 } 1077 1078 void 1079 pbreassignbuf(bp, newvp) 1080 struct buf *bp; 1081 struct vnode *newvp; 1082 { 1083 #if !defined(MAX_PERF) 1084 if ((bp->b_flags & B_PAGING) == 0) { 1085 panic( 1086 "pbreassignbuf() on non phys bp %p", 1087 bp 1088 ); 1089 } 1090 #endif 1091 bp->b_vp = newvp; 1092 } 1093 1094 /* 1095 * Reassign a buffer from one vnode to another. 1096 * Used to assign file specific control information 1097 * (indirect blocks) to the vnode to which they belong. 1098 */ 1099 void 1100 reassignbuf(bp, newvp) 1101 register struct buf *bp; 1102 register struct vnode *newvp; 1103 { 1104 struct buflists *listheadp; 1105 int delay; 1106 int s; 1107 1108 if (newvp == NULL) { 1109 printf("reassignbuf: NULL"); 1110 return; 1111 } 1112 1113 #if !defined(MAX_PERF) 1114 /* 1115 * B_PAGING flagged buffers cannot be reassigned because their vp 1116 * is not fully linked in. 1117 */ 1118 if (bp->b_flags & B_PAGING) 1119 panic("cannot reassign paging buffer"); 1120 #endif 1121 1122 s = splbio(); 1123 /* 1124 * Delete from old vnode list, if on one. 1125 */ 1126 if (bp->b_xflags & (B_VNDIRTY|B_VNCLEAN)) { 1127 if (bp->b_xflags & B_VNDIRTY) 1128 listheadp = &bp->b_vp->v_dirtyblkhd; 1129 else 1130 listheadp = &bp->b_vp->v_cleanblkhd; 1131 TAILQ_REMOVE(listheadp, bp, b_vnbufs); 1132 bp->b_xflags &= ~(B_VNDIRTY|B_VNCLEAN); 1133 if (bp->b_vp != newvp) { 1134 vdrop(bp->b_vp); 1135 bp->b_vp = NULL; /* for clarification */ 1136 } 1137 } 1138 /* 1139 * If dirty, put on list of dirty buffers; otherwise insert onto list 1140 * of clean buffers. 1141 */ 1142 if (bp->b_flags & B_DELWRI) { 1143 struct buf *tbp; 1144 1145 listheadp = &newvp->v_dirtyblkhd; 1146 if ((newvp->v_flag & VONWORKLST) == 0) { 1147 switch (newvp->v_type) { 1148 case VDIR: 1149 delay = dirdelay; 1150 break; 1151 case VBLK: 1152 if (newvp->v_specmountpoint != NULL) { 1153 delay = metadelay; 1154 break; 1155 } 1156 /* fall through */ 1157 default: 1158 delay = filedelay; 1159 } 1160 vn_syncer_add_to_worklist(newvp, delay); 1161 } 1162 bp->b_xflags |= B_VNDIRTY; 1163 tbp = TAILQ_FIRST(listheadp); 1164 if (tbp == NULL || 1165 (bp->b_lblkno >= 0 && tbp->b_lblkno > bp->b_lblkno)) { 1166 TAILQ_INSERT_HEAD(listheadp, bp, b_vnbufs); 1167 } else { 1168 if (bp->b_lblkno >= 0) { 1169 struct buf *ttbp; 1170 while ((ttbp = TAILQ_NEXT(tbp, b_vnbufs)) && 1171 (ttbp->b_lblkno < bp->b_lblkno)) { 1172 tbp = ttbp; 1173 } 1174 TAILQ_INSERT_AFTER(listheadp, tbp, bp, b_vnbufs); 1175 } else { 1176 TAILQ_INSERT_TAIL(listheadp, bp, b_vnbufs); 1177 } 1178 } 1179 } else { 1180 bp->b_xflags |= B_VNCLEAN; 1181 TAILQ_INSERT_TAIL(&newvp->v_cleanblkhd, bp, b_vnbufs); 1182 if ((newvp->v_flag & VONWORKLST) && 1183 TAILQ_EMPTY(&newvp->v_dirtyblkhd)) { 1184 newvp->v_flag &= ~VONWORKLST; 1185 LIST_REMOVE(newvp, v_synclist); 1186 } 1187 } 1188 if (bp->b_vp != newvp) { 1189 bp->b_vp = newvp; 1190 vhold(bp->b_vp); 1191 } 1192 splx(s); 1193 } 1194 1195 /* 1196 * Create a vnode for a block device. 1197 * Used for mounting the root file system. 1198 */ 1199 int 1200 bdevvp(dev, vpp) 1201 dev_t dev; 1202 struct vnode **vpp; 1203 { 1204 register struct vnode *vp; 1205 struct vnode *nvp; 1206 int error; 1207 1208 if (dev == NODEV) { 1209 *vpp = NULLVP; 1210 return (ENXIO); 1211 } 1212 error = getnewvnode(VT_NON, (struct mount *)0, spec_vnodeop_p, &nvp); 1213 if (error) { 1214 *vpp = NULLVP; 1215 return (error); 1216 } 1217 vp = nvp; 1218 vp->v_type = VBLK; 1219 if ((nvp = checkalias(vp, dev2udev(dev), (struct mount *)0)) != NULL) { 1220 vput(vp); 1221 vp = nvp; 1222 } 1223 *vpp = vp; 1224 return (0); 1225 } 1226 1227 /* 1228 * Check to see if the new vnode represents a special device 1229 * for which we already have a vnode (either because of 1230 * bdevvp() or because of a different vnode representing 1231 * the same block device). If such an alias exists, deallocate 1232 * the existing contents and return the aliased vnode. The 1233 * caller is responsible for filling it with its new contents. 1234 */ 1235 struct vnode * 1236 checkalias(nvp, nvp_rdev, mp) 1237 register struct vnode *nvp; 1238 udev_t nvp_rdev; 1239 struct mount *mp; 1240 { 1241 struct proc *p = curproc; /* XXX */ 1242 struct vnode *vp; 1243 struct vnode **vpp; 1244 dev_t dev; 1245 1246 if (nvp->v_type != VBLK && nvp->v_type != VCHR) 1247 return (NULLVP); 1248 1249 dev = udev2dev(nvp_rdev, 2); 1250 1251 vpp = &speclisth[SPECHASH(dev)]; 1252 loop: 1253 simple_lock(&spechash_slock); 1254 for (vp = *vpp; vp; vp = vp->v_specnext) { 1255 if (dev != vp->v_rdev || nvp->v_type != vp->v_type) 1256 continue; 1257 /* 1258 * Alias, but not in use, so flush it out. 1259 * Only alias active device nodes. 1260 * Not sure why we don't re-use this like we do below. 1261 */ 1262 simple_lock(&vp->v_interlock); 1263 if (vp->v_usecount == 0) { 1264 simple_unlock(&spechash_slock); 1265 vgonel(vp, p); 1266 goto loop; 1267 } 1268 if (vget(vp, LK_EXCLUSIVE | LK_INTERLOCK, p)) { 1269 /* 1270 * It dissappeared, and we may have slept. 1271 * Restart from the beginning 1272 */ 1273 simple_unlock(&spechash_slock); 1274 goto loop; 1275 } 1276 break; 1277 } 1278 /* 1279 * It would be a lot clearer what is going on here if 1280 * this had been expressed as: 1281 * if ( vp && (vp->v_tag == VT_NULL)) 1282 * and the clauses had been swapped. 1283 */ 1284 if (vp == NULL || vp->v_tag != VT_NON) { 1285 struct specinfo *sinfo; 1286 1287 /* 1288 * Put the new vnode into the hash chain. 1289 * and if there was an alias, connect them. 1290 */ 1291 MALLOC(sinfo, struct specinfo *, 1292 sizeof(struct specinfo), M_VNODE, M_WAITOK); 1293 bzero(sinfo, sizeof(struct specinfo)); 1294 nvp->v_specinfo = sinfo; 1295 sinfo->si_rdev = dev; 1296 sinfo->si_hashchain = vpp; 1297 sinfo->si_specnext = *vpp; 1298 sinfo->si_bsize_phys = DEV_BSIZE; 1299 sinfo->si_bsize_best = BLKDEV_IOSIZE; 1300 sinfo->si_bsize_max = MAXBSIZE; 1301 1302 /* 1303 * Ask the device to fix up specinfo. Typically the 1304 * si_bsize_* parameters may need fixing up. 1305 */ 1306 1307 if (nvp->v_type == VBLK) { 1308 if (bdevsw(dev) && bdevsw(dev)->d_parms) 1309 (*bdevsw(dev)->d_parms)(dev, sinfo, DPARM_GET); 1310 } else if (nvp->v_type == VCHR) { 1311 if (devsw(dev) && devsw(dev)->d_parms) 1312 (*devsw(dev)->d_parms)(dev, sinfo, DPARM_GET); 1313 } 1314 1315 simple_unlock(&spechash_slock); 1316 *vpp = nvp; 1317 if (vp != NULLVP) { 1318 nvp->v_flag |= VALIASED; 1319 vp->v_flag |= VALIASED; 1320 vput(vp); 1321 } 1322 return (NULLVP); 1323 } 1324 /* 1325 * if ( vp && (vp->v_tag == VT_NULL)) 1326 * We have a vnode alias, but it is a trashed. 1327 * Make it look like it's newley allocated. (by getnewvnode()) 1328 * The caller should use this instead. 1329 */ 1330 simple_unlock(&spechash_slock); 1331 VOP_UNLOCK(vp, 0, p); 1332 simple_lock(&vp->v_interlock); 1333 vclean(vp, 0, p); 1334 vp->v_op = nvp->v_op; 1335 vp->v_tag = nvp->v_tag; 1336 nvp->v_type = VNON; 1337 insmntque(vp, mp); 1338 return (vp); 1339 } 1340 1341 /* 1342 * Grab a particular vnode from the free list, increment its 1343 * reference count and lock it. The vnode lock bit is set the 1344 * vnode is being eliminated in vgone. The process is awakened 1345 * when the transition is completed, and an error returned to 1346 * indicate that the vnode is no longer usable (possibly having 1347 * been changed to a new file system type). 1348 */ 1349 int 1350 vget(vp, flags, p) 1351 register struct vnode *vp; 1352 int flags; 1353 struct proc *p; 1354 { 1355 int error; 1356 1357 /* 1358 * If the vnode is in the process of being cleaned out for 1359 * another use, we wait for the cleaning to finish and then 1360 * return failure. Cleaning is determined by checking that 1361 * the VXLOCK flag is set. 1362 */ 1363 if ((flags & LK_INTERLOCK) == 0) { 1364 simple_lock(&vp->v_interlock); 1365 } 1366 if (vp->v_flag & VXLOCK) { 1367 vp->v_flag |= VXWANT; 1368 simple_unlock(&vp->v_interlock); 1369 tsleep((caddr_t)vp, PINOD, "vget", 0); 1370 return (ENOENT); 1371 } 1372 1373 vp->v_usecount++; 1374 1375 if (VSHOULDBUSY(vp)) 1376 vbusy(vp); 1377 if (flags & LK_TYPE_MASK) { 1378 if ((error = vn_lock(vp, flags | LK_INTERLOCK, p)) != 0) { 1379 /* 1380 * must expand vrele here because we do not want 1381 * to call VOP_INACTIVE if the reference count 1382 * drops back to zero since it was never really 1383 * active. We must remove it from the free list 1384 * before sleeping so that multiple processes do 1385 * not try to recycle it. 1386 */ 1387 simple_lock(&vp->v_interlock); 1388 vp->v_usecount--; 1389 if (VSHOULDFREE(vp)) 1390 vfree(vp); 1391 simple_unlock(&vp->v_interlock); 1392 } 1393 return (error); 1394 } 1395 simple_unlock(&vp->v_interlock); 1396 return (0); 1397 } 1398 1399 void 1400 vref(struct vnode *vp) 1401 { 1402 simple_lock(&vp->v_interlock); 1403 vp->v_usecount++; 1404 simple_unlock(&vp->v_interlock); 1405 } 1406 1407 /* 1408 * Vnode put/release. 1409 * If count drops to zero, call inactive routine and return to freelist. 1410 */ 1411 void 1412 vrele(vp) 1413 struct vnode *vp; 1414 { 1415 struct proc *p = curproc; /* XXX */ 1416 1417 KASSERT(vp != NULL, ("vrele: null vp")); 1418 1419 simple_lock(&vp->v_interlock); 1420 1421 if (vp->v_usecount > 1) { 1422 1423 vp->v_usecount--; 1424 simple_unlock(&vp->v_interlock); 1425 1426 return; 1427 } 1428 1429 if (vp->v_usecount == 1) { 1430 1431 vp->v_usecount--; 1432 if (VSHOULDFREE(vp)) 1433 vfree(vp); 1434 /* 1435 * If we are doing a vput, the node is already locked, and we must 1436 * call VOP_INACTIVE with the node locked. So, in the case of 1437 * vrele, we explicitly lock the vnode before calling VOP_INACTIVE. 1438 */ 1439 if (vn_lock(vp, LK_EXCLUSIVE | LK_INTERLOCK, p) == 0) { 1440 VOP_INACTIVE(vp, p); 1441 } 1442 1443 } else { 1444 #ifdef DIAGNOSTIC 1445 vprint("vrele: negative ref count", vp); 1446 simple_unlock(&vp->v_interlock); 1447 #endif 1448 panic("vrele: negative ref cnt"); 1449 } 1450 } 1451 1452 void 1453 vput(vp) 1454 struct vnode *vp; 1455 { 1456 struct proc *p = curproc; /* XXX */ 1457 1458 KASSERT(vp != NULL, ("vput: null vp")); 1459 1460 simple_lock(&vp->v_interlock); 1461 1462 if (vp->v_usecount > 1) { 1463 1464 vp->v_usecount--; 1465 VOP_UNLOCK(vp, LK_INTERLOCK, p); 1466 return; 1467 1468 } 1469 1470 if (vp->v_usecount == 1) { 1471 1472 vp->v_usecount--; 1473 if (VSHOULDFREE(vp)) 1474 vfree(vp); 1475 /* 1476 * If we are doing a vput, the node is already locked, and we must 1477 * call VOP_INACTIVE with the node locked. So, in the case of 1478 * vrele, we explicitly lock the vnode before calling VOP_INACTIVE. 1479 */ 1480 simple_unlock(&vp->v_interlock); 1481 VOP_INACTIVE(vp, p); 1482 1483 } else { 1484 #ifdef DIAGNOSTIC 1485 vprint("vput: negative ref count", vp); 1486 #endif 1487 panic("vput: negative ref cnt"); 1488 } 1489 } 1490 1491 /* 1492 * Somebody doesn't want the vnode recycled. 1493 */ 1494 void 1495 vhold(vp) 1496 register struct vnode *vp; 1497 { 1498 int s; 1499 1500 s = splbio(); 1501 vp->v_holdcnt++; 1502 if (VSHOULDBUSY(vp)) 1503 vbusy(vp); 1504 splx(s); 1505 } 1506 1507 /* 1508 * One less who cares about this vnode. 1509 */ 1510 void 1511 vdrop(vp) 1512 register struct vnode *vp; 1513 { 1514 int s; 1515 1516 s = splbio(); 1517 if (vp->v_holdcnt <= 0) 1518 panic("vdrop: holdcnt"); 1519 vp->v_holdcnt--; 1520 if (VSHOULDFREE(vp)) 1521 vfree(vp); 1522 splx(s); 1523 } 1524 1525 /* 1526 * Remove any vnodes in the vnode table belonging to mount point mp. 1527 * 1528 * If MNT_NOFORCE is specified, there should not be any active ones, 1529 * return error if any are found (nb: this is a user error, not a 1530 * system error). If MNT_FORCE is specified, detach any active vnodes 1531 * that are found. 1532 */ 1533 #ifdef DIAGNOSTIC 1534 static int busyprt = 0; /* print out busy vnodes */ 1535 SYSCTL_INT(_debug, OID_AUTO, busyprt, CTLFLAG_RW, &busyprt, 0, ""); 1536 #endif 1537 1538 int 1539 vflush(mp, skipvp, flags) 1540 struct mount *mp; 1541 struct vnode *skipvp; 1542 int flags; 1543 { 1544 struct proc *p = curproc; /* XXX */ 1545 struct vnode *vp, *nvp; 1546 int busy = 0; 1547 1548 simple_lock(&mntvnode_slock); 1549 loop: 1550 for (vp = mp->mnt_vnodelist.lh_first; vp; vp = nvp) { 1551 /* 1552 * Make sure this vnode wasn't reclaimed in getnewvnode(). 1553 * Start over if it has (it won't be on the list anymore). 1554 */ 1555 if (vp->v_mount != mp) 1556 goto loop; 1557 nvp = vp->v_mntvnodes.le_next; 1558 /* 1559 * Skip over a selected vnode. 1560 */ 1561 if (vp == skipvp) 1562 continue; 1563 1564 simple_lock(&vp->v_interlock); 1565 /* 1566 * Skip over a vnodes marked VSYSTEM. 1567 */ 1568 if ((flags & SKIPSYSTEM) && (vp->v_flag & VSYSTEM)) { 1569 simple_unlock(&vp->v_interlock); 1570 continue; 1571 } 1572 /* 1573 * If WRITECLOSE is set, only flush out regular file vnodes 1574 * open for writing. 1575 */ 1576 if ((flags & WRITECLOSE) && 1577 (vp->v_writecount == 0 || vp->v_type != VREG)) { 1578 simple_unlock(&vp->v_interlock); 1579 continue; 1580 } 1581 1582 /* 1583 * With v_usecount == 0, all we need to do is clear out the 1584 * vnode data structures and we are done. 1585 */ 1586 if (vp->v_usecount == 0) { 1587 simple_unlock(&mntvnode_slock); 1588 vgonel(vp, p); 1589 simple_lock(&mntvnode_slock); 1590 continue; 1591 } 1592 1593 /* 1594 * If FORCECLOSE is set, forcibly close the vnode. For block 1595 * or character devices, revert to an anonymous device. For 1596 * all other files, just kill them. 1597 */ 1598 if (flags & FORCECLOSE) { 1599 simple_unlock(&mntvnode_slock); 1600 if (vp->v_type != VBLK && vp->v_type != VCHR) { 1601 vgonel(vp, p); 1602 } else { 1603 vclean(vp, 0, p); 1604 vp->v_op = spec_vnodeop_p; 1605 insmntque(vp, (struct mount *) 0); 1606 } 1607 simple_lock(&mntvnode_slock); 1608 continue; 1609 } 1610 #ifdef DIAGNOSTIC 1611 if (busyprt) 1612 vprint("vflush: busy vnode", vp); 1613 #endif 1614 simple_unlock(&vp->v_interlock); 1615 busy++; 1616 } 1617 simple_unlock(&mntvnode_slock); 1618 if (busy) 1619 return (EBUSY); 1620 return (0); 1621 } 1622 1623 /* 1624 * Disassociate the underlying file system from a vnode. 1625 */ 1626 static void 1627 vclean(vp, flags, p) 1628 struct vnode *vp; 1629 int flags; 1630 struct proc *p; 1631 { 1632 int active; 1633 vm_object_t obj; 1634 1635 /* 1636 * Check to see if the vnode is in use. If so we have to reference it 1637 * before we clean it out so that its count cannot fall to zero and 1638 * generate a race against ourselves to recycle it. 1639 */ 1640 if ((active = vp->v_usecount)) 1641 vp->v_usecount++; 1642 1643 /* 1644 * Prevent the vnode from being recycled or brought into use while we 1645 * clean it out. 1646 */ 1647 if (vp->v_flag & VXLOCK) 1648 panic("vclean: deadlock"); 1649 vp->v_flag |= VXLOCK; 1650 /* 1651 * Even if the count is zero, the VOP_INACTIVE routine may still 1652 * have the object locked while it cleans it out. The VOP_LOCK 1653 * ensures that the VOP_INACTIVE routine is done with its work. 1654 * For active vnodes, it ensures that no other activity can 1655 * occur while the underlying object is being cleaned out. 1656 */ 1657 VOP_LOCK(vp, LK_DRAIN | LK_INTERLOCK, p); 1658 1659 /* 1660 * Clean out any buffers associated with the vnode. 1661 */ 1662 vinvalbuf(vp, V_SAVE, NOCRED, p, 0, 0); 1663 if ((obj = vp->v_object) != NULL) { 1664 if (obj->ref_count == 0) { 1665 /* 1666 * This is a normal way of shutting down the object/vnode 1667 * association. 1668 */ 1669 vm_object_terminate(obj); 1670 } else { 1671 /* 1672 * Woe to the process that tries to page now :-). 1673 */ 1674 vm_pager_deallocate(obj); 1675 } 1676 } 1677 1678 /* 1679 * If purging an active vnode, it must be closed and 1680 * deactivated before being reclaimed. Note that the 1681 * VOP_INACTIVE will unlock the vnode. 1682 */ 1683 if (active) { 1684 if (flags & DOCLOSE) 1685 VOP_CLOSE(vp, FNONBLOCK, NOCRED, p); 1686 VOP_INACTIVE(vp, p); 1687 } else { 1688 /* 1689 * Any other processes trying to obtain this lock must first 1690 * wait for VXLOCK to clear, then call the new lock operation. 1691 */ 1692 VOP_UNLOCK(vp, 0, p); 1693 } 1694 /* 1695 * Reclaim the vnode. 1696 */ 1697 if (VOP_RECLAIM(vp, p)) 1698 panic("vclean: cannot reclaim"); 1699 1700 if (active) 1701 vrele(vp); 1702 1703 cache_purge(vp); 1704 if (vp->v_vnlock) { 1705 #if 0 /* This is the only place we have LK_DRAINED in the entire kernel ??? */ 1706 #ifdef DIAGNOSTIC 1707 if ((vp->v_vnlock->lk_flags & LK_DRAINED) == 0) 1708 vprint("vclean: lock not drained", vp); 1709 #endif 1710 #endif 1711 FREE(vp->v_vnlock, M_VNODE); 1712 vp->v_vnlock = NULL; 1713 } 1714 1715 if (VSHOULDFREE(vp)) 1716 vfree(vp); 1717 1718 /* 1719 * Done with purge, notify sleepers of the grim news. 1720 */ 1721 vp->v_op = dead_vnodeop_p; 1722 vn_pollgone(vp); 1723 vp->v_tag = VT_NON; 1724 vp->v_flag &= ~VXLOCK; 1725 if (vp->v_flag & VXWANT) { 1726 vp->v_flag &= ~VXWANT; 1727 wakeup((caddr_t) vp); 1728 } 1729 } 1730 1731 /* 1732 * Eliminate all activity associated with the requested vnode 1733 * and with all vnodes aliased to the requested vnode. 1734 */ 1735 int 1736 vop_revoke(ap) 1737 struct vop_revoke_args /* { 1738 struct vnode *a_vp; 1739 int a_flags; 1740 } */ *ap; 1741 { 1742 struct vnode *vp, *vq; 1743 struct proc *p = curproc; /* XXX */ 1744 1745 KASSERT((ap->a_flags & REVOKEALL) != 0, ("vop_revoke")); 1746 1747 vp = ap->a_vp; 1748 simple_lock(&vp->v_interlock); 1749 1750 if (vp->v_flag & VALIASED) { 1751 /* 1752 * If a vgone (or vclean) is already in progress, 1753 * wait until it is done and return. 1754 */ 1755 if (vp->v_flag & VXLOCK) { 1756 vp->v_flag |= VXWANT; 1757 simple_unlock(&vp->v_interlock); 1758 tsleep((caddr_t)vp, PINOD, "vop_revokeall", 0); 1759 return (0); 1760 } 1761 /* 1762 * Ensure that vp will not be vgone'd while we 1763 * are eliminating its aliases. 1764 */ 1765 vp->v_flag |= VXLOCK; 1766 simple_unlock(&vp->v_interlock); 1767 while (vp->v_flag & VALIASED) { 1768 simple_lock(&spechash_slock); 1769 for (vq = *vp->v_hashchain; vq; vq = vq->v_specnext) { 1770 if (vq->v_rdev != vp->v_rdev || 1771 vq->v_type != vp->v_type || vp == vq) 1772 continue; 1773 simple_unlock(&spechash_slock); 1774 vgone(vq); 1775 break; 1776 } 1777 if (vq == NULLVP) { 1778 simple_unlock(&spechash_slock); 1779 } 1780 } 1781 /* 1782 * Remove the lock so that vgone below will 1783 * really eliminate the vnode after which time 1784 * vgone will awaken any sleepers. 1785 */ 1786 simple_lock(&vp->v_interlock); 1787 vp->v_flag &= ~VXLOCK; 1788 if (vp->v_flag & VXWANT) { 1789 vp->v_flag &= ~VXWANT; 1790 wakeup(vp); 1791 } 1792 } 1793 vgonel(vp, p); 1794 return (0); 1795 } 1796 1797 /* 1798 * Recycle an unused vnode to the front of the free list. 1799 * Release the passed interlock if the vnode will be recycled. 1800 */ 1801 int 1802 vrecycle(vp, inter_lkp, p) 1803 struct vnode *vp; 1804 struct simplelock *inter_lkp; 1805 struct proc *p; 1806 { 1807 1808 simple_lock(&vp->v_interlock); 1809 if (vp->v_usecount == 0) { 1810 if (inter_lkp) { 1811 simple_unlock(inter_lkp); 1812 } 1813 vgonel(vp, p); 1814 return (1); 1815 } 1816 simple_unlock(&vp->v_interlock); 1817 return (0); 1818 } 1819 1820 /* 1821 * Eliminate all activity associated with a vnode 1822 * in preparation for reuse. 1823 */ 1824 void 1825 vgone(vp) 1826 register struct vnode *vp; 1827 { 1828 struct proc *p = curproc; /* XXX */ 1829 1830 simple_lock(&vp->v_interlock); 1831 vgonel(vp, p); 1832 } 1833 1834 /* 1835 * vgone, with the vp interlock held. 1836 */ 1837 static void 1838 vgonel(vp, p) 1839 struct vnode *vp; 1840 struct proc *p; 1841 { 1842 int s; 1843 struct vnode *vq; 1844 struct vnode *vx; 1845 1846 /* 1847 * If a vgone (or vclean) is already in progress, 1848 * wait until it is done and return. 1849 */ 1850 if (vp->v_flag & VXLOCK) { 1851 vp->v_flag |= VXWANT; 1852 simple_unlock(&vp->v_interlock); 1853 tsleep((caddr_t)vp, PINOD, "vgone", 0); 1854 return; 1855 } 1856 1857 /* 1858 * Clean out the filesystem specific data. 1859 */ 1860 vclean(vp, DOCLOSE, p); 1861 simple_lock(&vp->v_interlock); 1862 1863 /* 1864 * Delete from old mount point vnode list, if on one. 1865 */ 1866 if (vp->v_mount != NULL) 1867 insmntque(vp, (struct mount *)0); 1868 /* 1869 * If special device, remove it from special device alias list 1870 * if it is on one. 1871 */ 1872 if ((vp->v_type == VBLK || vp->v_type == VCHR) && vp->v_specinfo != 0) { 1873 simple_lock(&spechash_slock); 1874 if (*vp->v_hashchain == vp) { 1875 *vp->v_hashchain = vp->v_specnext; 1876 } else { 1877 for (vq = *vp->v_hashchain; vq; vq = vq->v_specnext) { 1878 if (vq->v_specnext != vp) 1879 continue; 1880 vq->v_specnext = vp->v_specnext; 1881 break; 1882 } 1883 if (vq == NULL) 1884 panic("missing bdev"); 1885 } 1886 if (vp->v_flag & VALIASED) { 1887 vx = NULL; 1888 for (vq = *vp->v_hashchain; vq; vq = vq->v_specnext) { 1889 if (vq->v_rdev != vp->v_rdev || 1890 vq->v_type != vp->v_type) 1891 continue; 1892 if (vx) 1893 break; 1894 vx = vq; 1895 } 1896 if (vx == NULL) 1897 panic("missing alias"); 1898 if (vq == NULL) 1899 vx->v_flag &= ~VALIASED; 1900 vp->v_flag &= ~VALIASED; 1901 } 1902 simple_unlock(&spechash_slock); 1903 FREE(vp->v_specinfo, M_VNODE); 1904 vp->v_specinfo = NULL; 1905 } 1906 1907 /* 1908 * If it is on the freelist and not already at the head, 1909 * move it to the head of the list. The test of the back 1910 * pointer and the reference count of zero is because 1911 * it will be removed from the free list by getnewvnode, 1912 * but will not have its reference count incremented until 1913 * after calling vgone. If the reference count were 1914 * incremented first, vgone would (incorrectly) try to 1915 * close the previous instance of the underlying object. 1916 */ 1917 if (vp->v_usecount == 0 && !(vp->v_flag & VDOOMED)) { 1918 s = splbio(); 1919 simple_lock(&vnode_free_list_slock); 1920 if (vp->v_flag & VFREE) { 1921 TAILQ_REMOVE(&vnode_free_list, vp, v_freelist); 1922 } else if (vp->v_flag & VTBFREE) { 1923 TAILQ_REMOVE(&vnode_tobefree_list, vp, v_freelist); 1924 vp->v_flag &= ~VTBFREE; 1925 freevnodes++; 1926 } else 1927 freevnodes++; 1928 vp->v_flag |= VFREE; 1929 TAILQ_INSERT_HEAD(&vnode_free_list, vp, v_freelist); 1930 simple_unlock(&vnode_free_list_slock); 1931 splx(s); 1932 } 1933 1934 vp->v_type = VBAD; 1935 simple_unlock(&vp->v_interlock); 1936 } 1937 1938 /* 1939 * Lookup a vnode by device number. 1940 */ 1941 int 1942 vfinddev(dev, type, vpp) 1943 dev_t dev; 1944 enum vtype type; 1945 struct vnode **vpp; 1946 { 1947 register struct vnode *vp; 1948 int rc = 0; 1949 1950 simple_lock(&spechash_slock); 1951 for (vp = speclisth[SPECHASH(dev)]; vp; vp = vp->v_specnext) { 1952 if (dev != vp->v_rdev || type != vp->v_type) 1953 continue; 1954 *vpp = vp; 1955 rc = 1; 1956 break; 1957 } 1958 simple_unlock(&spechash_slock); 1959 return (rc); 1960 } 1961 1962 /* 1963 * Calculate the total number of references to a special device. 1964 */ 1965 int 1966 vcount(vp) 1967 register struct vnode *vp; 1968 { 1969 struct vnode *vq, *vnext; 1970 int count; 1971 1972 loop: 1973 if ((vp->v_flag & VALIASED) == 0) 1974 return (vp->v_usecount); 1975 simple_lock(&spechash_slock); 1976 for (count = 0, vq = *vp->v_hashchain; vq; vq = vnext) { 1977 vnext = vq->v_specnext; 1978 if (vq->v_rdev != vp->v_rdev || vq->v_type != vp->v_type) 1979 continue; 1980 /* 1981 * Alias, but not in use, so flush it out. 1982 */ 1983 if (vq->v_usecount == 0 && vq != vp) { 1984 simple_unlock(&spechash_slock); 1985 vgone(vq); 1986 goto loop; 1987 } 1988 count += vq->v_usecount; 1989 } 1990 simple_unlock(&spechash_slock); 1991 return (count); 1992 } 1993 /* 1994 * Print out a description of a vnode. 1995 */ 1996 static char *typename[] = 1997 {"VNON", "VREG", "VDIR", "VBLK", "VCHR", "VLNK", "VSOCK", "VFIFO", "VBAD"}; 1998 1999 void 2000 vprint(label, vp) 2001 char *label; 2002 register struct vnode *vp; 2003 { 2004 char buf[96]; 2005 2006 if (label != NULL) 2007 printf("%s: %p: ", label, (void *)vp); 2008 else 2009 printf("%p: ", (void *)vp); 2010 printf("type %s, usecount %d, writecount %d, refcount %d,", 2011 typename[vp->v_type], vp->v_usecount, vp->v_writecount, 2012 vp->v_holdcnt); 2013 buf[0] = '\0'; 2014 if (vp->v_flag & VROOT) 2015 strcat(buf, "|VROOT"); 2016 if (vp->v_flag & VTEXT) 2017 strcat(buf, "|VTEXT"); 2018 if (vp->v_flag & VSYSTEM) 2019 strcat(buf, "|VSYSTEM"); 2020 if (vp->v_flag & VXLOCK) 2021 strcat(buf, "|VXLOCK"); 2022 if (vp->v_flag & VXWANT) 2023 strcat(buf, "|VXWANT"); 2024 if (vp->v_flag & VBWAIT) 2025 strcat(buf, "|VBWAIT"); 2026 if (vp->v_flag & VALIASED) 2027 strcat(buf, "|VALIASED"); 2028 if (vp->v_flag & VDOOMED) 2029 strcat(buf, "|VDOOMED"); 2030 if (vp->v_flag & VFREE) 2031 strcat(buf, "|VFREE"); 2032 if (vp->v_flag & VOBJBUF) 2033 strcat(buf, "|VOBJBUF"); 2034 if (buf[0] != '\0') 2035 printf(" flags (%s)", &buf[1]); 2036 if (vp->v_data == NULL) { 2037 printf("\n"); 2038 } else { 2039 printf("\n\t"); 2040 VOP_PRINT(vp); 2041 } 2042 } 2043 2044 #ifdef DDB 2045 #include <ddb/ddb.h> 2046 /* 2047 * List all of the locked vnodes in the system. 2048 * Called when debugging the kernel. 2049 */ 2050 DB_SHOW_COMMAND(lockedvnodes, lockedvnodes) 2051 { 2052 struct proc *p = curproc; /* XXX */ 2053 struct mount *mp, *nmp; 2054 struct vnode *vp; 2055 2056 printf("Locked vnodes\n"); 2057 simple_lock(&mountlist_slock); 2058 for (mp = mountlist.cqh_first; mp != (void *)&mountlist; mp = nmp) { 2059 if (vfs_busy(mp, LK_NOWAIT, &mountlist_slock, p)) { 2060 nmp = mp->mnt_list.cqe_next; 2061 continue; 2062 } 2063 for (vp = mp->mnt_vnodelist.lh_first; 2064 vp != NULL; 2065 vp = vp->v_mntvnodes.le_next) { 2066 if (VOP_ISLOCKED(vp)) 2067 vprint((char *)0, vp); 2068 } 2069 simple_lock(&mountlist_slock); 2070 nmp = mp->mnt_list.cqe_next; 2071 vfs_unbusy(mp, p); 2072 } 2073 simple_unlock(&mountlist_slock); 2074 } 2075 #endif 2076 2077 /* 2078 * Top level filesystem related information gathering. 2079 */ 2080 static int sysctl_ovfs_conf __P(SYSCTL_HANDLER_ARGS); 2081 2082 static int 2083 vfs_sysctl SYSCTL_HANDLER_ARGS 2084 { 2085 int *name = (int *)arg1 - 1; /* XXX */ 2086 u_int namelen = arg2 + 1; /* XXX */ 2087 struct vfsconf *vfsp; 2088 2089 #if 1 || defined(COMPAT_PRELITE2) 2090 /* Resolve ambiguity between VFS_VFSCONF and VFS_GENERIC. */ 2091 if (namelen == 1) 2092 return (sysctl_ovfs_conf(oidp, arg1, arg2, req)); 2093 #endif 2094 2095 #ifdef notyet 2096 /* all sysctl names at this level are at least name and field */ 2097 if (namelen < 2) 2098 return (ENOTDIR); /* overloaded */ 2099 if (name[0] != VFS_GENERIC) { 2100 for (vfsp = vfsconf; vfsp; vfsp = vfsp->vfc_next) 2101 if (vfsp->vfc_typenum == name[0]) 2102 break; 2103 if (vfsp == NULL) 2104 return (EOPNOTSUPP); 2105 return ((*vfsp->vfc_vfsops->vfs_sysctl)(&name[1], namelen - 1, 2106 oldp, oldlenp, newp, newlen, p)); 2107 } 2108 #endif 2109 switch (name[1]) { 2110 case VFS_MAXTYPENUM: 2111 if (namelen != 2) 2112 return (ENOTDIR); 2113 return (SYSCTL_OUT(req, &maxvfsconf, sizeof(int))); 2114 case VFS_CONF: 2115 if (namelen != 3) 2116 return (ENOTDIR); /* overloaded */ 2117 for (vfsp = vfsconf; vfsp; vfsp = vfsp->vfc_next) 2118 if (vfsp->vfc_typenum == name[2]) 2119 break; 2120 if (vfsp == NULL) 2121 return (EOPNOTSUPP); 2122 return (SYSCTL_OUT(req, vfsp, sizeof *vfsp)); 2123 } 2124 return (EOPNOTSUPP); 2125 } 2126 2127 SYSCTL_NODE(_vfs, VFS_GENERIC, generic, CTLFLAG_RD, vfs_sysctl, 2128 "Generic filesystem"); 2129 2130 #if 1 || defined(COMPAT_PRELITE2) 2131 2132 static int 2133 sysctl_ovfs_conf SYSCTL_HANDLER_ARGS 2134 { 2135 int error; 2136 struct vfsconf *vfsp; 2137 struct ovfsconf ovfs; 2138 2139 for (vfsp = vfsconf; vfsp; vfsp = vfsp->vfc_next) { 2140 ovfs.vfc_vfsops = vfsp->vfc_vfsops; /* XXX used as flag */ 2141 strcpy(ovfs.vfc_name, vfsp->vfc_name); 2142 ovfs.vfc_index = vfsp->vfc_typenum; 2143 ovfs.vfc_refcount = vfsp->vfc_refcount; 2144 ovfs.vfc_flags = vfsp->vfc_flags; 2145 error = SYSCTL_OUT(req, &ovfs, sizeof ovfs); 2146 if (error) 2147 return error; 2148 } 2149 return 0; 2150 } 2151 2152 #endif /* 1 || COMPAT_PRELITE2 */ 2153 2154 #if 0 2155 #define KINFO_VNODESLOP 10 2156 /* 2157 * Dump vnode list (via sysctl). 2158 * Copyout address of vnode followed by vnode. 2159 */ 2160 /* ARGSUSED */ 2161 static int 2162 sysctl_vnode SYSCTL_HANDLER_ARGS 2163 { 2164 struct proc *p = curproc; /* XXX */ 2165 struct mount *mp, *nmp; 2166 struct vnode *nvp, *vp; 2167 int error; 2168 2169 #define VPTRSZ sizeof (struct vnode *) 2170 #define VNODESZ sizeof (struct vnode) 2171 2172 req->lock = 0; 2173 if (!req->oldptr) /* Make an estimate */ 2174 return (SYSCTL_OUT(req, 0, 2175 (numvnodes + KINFO_VNODESLOP) * (VPTRSZ + VNODESZ))); 2176 2177 simple_lock(&mountlist_slock); 2178 for (mp = mountlist.cqh_first; mp != (void *)&mountlist; mp = nmp) { 2179 if (vfs_busy(mp, LK_NOWAIT, &mountlist_slock, p)) { 2180 nmp = mp->mnt_list.cqe_next; 2181 continue; 2182 } 2183 again: 2184 simple_lock(&mntvnode_slock); 2185 for (vp = mp->mnt_vnodelist.lh_first; 2186 vp != NULL; 2187 vp = nvp) { 2188 /* 2189 * Check that the vp is still associated with 2190 * this filesystem. RACE: could have been 2191 * recycled onto the same filesystem. 2192 */ 2193 if (vp->v_mount != mp) { 2194 simple_unlock(&mntvnode_slock); 2195 goto again; 2196 } 2197 nvp = vp->v_mntvnodes.le_next; 2198 simple_unlock(&mntvnode_slock); 2199 if ((error = SYSCTL_OUT(req, &vp, VPTRSZ)) || 2200 (error = SYSCTL_OUT(req, vp, VNODESZ))) 2201 return (error); 2202 simple_lock(&mntvnode_slock); 2203 } 2204 simple_unlock(&mntvnode_slock); 2205 simple_lock(&mountlist_slock); 2206 nmp = mp->mnt_list.cqe_next; 2207 vfs_unbusy(mp, p); 2208 } 2209 simple_unlock(&mountlist_slock); 2210 2211 return (0); 2212 } 2213 #endif 2214 2215 /* 2216 * XXX 2217 * Exporting the vnode list on large systems causes them to crash. 2218 * Exporting the vnode list on medium systems causes sysctl to coredump. 2219 */ 2220 #if 0 2221 SYSCTL_PROC(_kern, KERN_VNODE, vnode, CTLTYPE_OPAQUE|CTLFLAG_RD, 2222 0, 0, sysctl_vnode, "S,vnode", ""); 2223 #endif 2224 2225 /* 2226 * Check to see if a filesystem is mounted on a block device. 2227 */ 2228 int 2229 vfs_mountedon(vp) 2230 struct vnode *vp; 2231 { 2232 struct vnode *vq; 2233 int error = 0; 2234 2235 if (vp->v_specmountpoint != NULL) 2236 return (EBUSY); 2237 if (vp->v_flag & VALIASED) { 2238 simple_lock(&spechash_slock); 2239 for (vq = *vp->v_hashchain; vq; vq = vq->v_specnext) { 2240 if (vq->v_rdev != vp->v_rdev || 2241 vq->v_type != vp->v_type) 2242 continue; 2243 if (vq->v_specmountpoint != NULL) { 2244 error = EBUSY; 2245 break; 2246 } 2247 } 2248 simple_unlock(&spechash_slock); 2249 } 2250 return (error); 2251 } 2252 2253 /* 2254 * Unmount all filesystems. The list is traversed in reverse order 2255 * of mounting to avoid dependencies. 2256 */ 2257 void 2258 vfs_unmountall() 2259 { 2260 struct mount *mp, *nmp; 2261 struct proc *p; 2262 int error; 2263 2264 if (curproc != NULL) 2265 p = curproc; 2266 else 2267 p = initproc; /* XXX XXX should this be proc0? */ 2268 /* 2269 * Since this only runs when rebooting, it is not interlocked. 2270 */ 2271 for (mp = mountlist.cqh_last; mp != (void *)&mountlist; mp = nmp) { 2272 nmp = mp->mnt_list.cqe_prev; 2273 error = dounmount(mp, MNT_FORCE, p); 2274 if (error) { 2275 printf("unmount of %s failed (", 2276 mp->mnt_stat.f_mntonname); 2277 if (error == EBUSY) 2278 printf("BUSY)\n"); 2279 else 2280 printf("%d)\n", error); 2281 } 2282 } 2283 } 2284 2285 /* 2286 * Build hash lists of net addresses and hang them off the mount point. 2287 * Called by ufs_mount() to set up the lists of export addresses. 2288 */ 2289 static int 2290 vfs_hang_addrlist(mp, nep, argp) 2291 struct mount *mp; 2292 struct netexport *nep; 2293 struct export_args *argp; 2294 { 2295 register struct netcred *np; 2296 register struct radix_node_head *rnh; 2297 register int i; 2298 struct radix_node *rn; 2299 struct sockaddr *saddr, *smask = 0; 2300 struct domain *dom; 2301 int error; 2302 2303 if (argp->ex_addrlen == 0) { 2304 if (mp->mnt_flag & MNT_DEFEXPORTED) 2305 return (EPERM); 2306 np = &nep->ne_defexported; 2307 np->netc_exflags = argp->ex_flags; 2308 np->netc_anon = argp->ex_anon; 2309 np->netc_anon.cr_ref = 1; 2310 mp->mnt_flag |= MNT_DEFEXPORTED; 2311 return (0); 2312 } 2313 i = sizeof(struct netcred) + argp->ex_addrlen + argp->ex_masklen; 2314 np = (struct netcred *) malloc(i, M_NETADDR, M_WAITOK); 2315 bzero((caddr_t) np, i); 2316 saddr = (struct sockaddr *) (np + 1); 2317 if ((error = copyin(argp->ex_addr, (caddr_t) saddr, argp->ex_addrlen))) 2318 goto out; 2319 if (saddr->sa_len > argp->ex_addrlen) 2320 saddr->sa_len = argp->ex_addrlen; 2321 if (argp->ex_masklen) { 2322 smask = (struct sockaddr *) ((caddr_t) saddr + argp->ex_addrlen); 2323 error = copyin(argp->ex_mask, (caddr_t) smask, argp->ex_masklen); 2324 if (error) 2325 goto out; 2326 if (smask->sa_len > argp->ex_masklen) 2327 smask->sa_len = argp->ex_masklen; 2328 } 2329 i = saddr->sa_family; 2330 if ((rnh = nep->ne_rtable[i]) == 0) { 2331 /* 2332 * Seems silly to initialize every AF when most are not used, 2333 * do so on demand here 2334 */ 2335 for (dom = domains; dom; dom = dom->dom_next) 2336 if (dom->dom_family == i && dom->dom_rtattach) { 2337 dom->dom_rtattach((void **) &nep->ne_rtable[i], 2338 dom->dom_rtoffset); 2339 break; 2340 } 2341 if ((rnh = nep->ne_rtable[i]) == 0) { 2342 error = ENOBUFS; 2343 goto out; 2344 } 2345 } 2346 rn = (*rnh->rnh_addaddr) ((caddr_t) saddr, (caddr_t) smask, rnh, 2347 np->netc_rnodes); 2348 if (rn == 0 || np != (struct netcred *) rn) { /* already exists */ 2349 error = EPERM; 2350 goto out; 2351 } 2352 np->netc_exflags = argp->ex_flags; 2353 np->netc_anon = argp->ex_anon; 2354 np->netc_anon.cr_ref = 1; 2355 return (0); 2356 out: 2357 free(np, M_NETADDR); 2358 return (error); 2359 } 2360 2361 /* ARGSUSED */ 2362 static int 2363 vfs_free_netcred(rn, w) 2364 struct radix_node *rn; 2365 void *w; 2366 { 2367 register struct radix_node_head *rnh = (struct radix_node_head *) w; 2368 2369 (*rnh->rnh_deladdr) (rn->rn_key, rn->rn_mask, rnh); 2370 free((caddr_t) rn, M_NETADDR); 2371 return (0); 2372 } 2373 2374 /* 2375 * Free the net address hash lists that are hanging off the mount points. 2376 */ 2377 static void 2378 vfs_free_addrlist(nep) 2379 struct netexport *nep; 2380 { 2381 register int i; 2382 register struct radix_node_head *rnh; 2383 2384 for (i = 0; i <= AF_MAX; i++) 2385 if ((rnh = nep->ne_rtable[i])) { 2386 (*rnh->rnh_walktree) (rnh, vfs_free_netcred, 2387 (caddr_t) rnh); 2388 free((caddr_t) rnh, M_RTABLE); 2389 nep->ne_rtable[i] = 0; 2390 } 2391 } 2392 2393 int 2394 vfs_export(mp, nep, argp) 2395 struct mount *mp; 2396 struct netexport *nep; 2397 struct export_args *argp; 2398 { 2399 int error; 2400 2401 if (argp->ex_flags & MNT_DELEXPORT) { 2402 if (mp->mnt_flag & MNT_EXPUBLIC) { 2403 vfs_setpublicfs(NULL, NULL, NULL); 2404 mp->mnt_flag &= ~MNT_EXPUBLIC; 2405 } 2406 vfs_free_addrlist(nep); 2407 mp->mnt_flag &= ~(MNT_EXPORTED | MNT_DEFEXPORTED); 2408 } 2409 if (argp->ex_flags & MNT_EXPORTED) { 2410 if (argp->ex_flags & MNT_EXPUBLIC) { 2411 if ((error = vfs_setpublicfs(mp, nep, argp)) != 0) 2412 return (error); 2413 mp->mnt_flag |= MNT_EXPUBLIC; 2414 } 2415 if ((error = vfs_hang_addrlist(mp, nep, argp))) 2416 return (error); 2417 mp->mnt_flag |= MNT_EXPORTED; 2418 } 2419 return (0); 2420 } 2421 2422 2423 /* 2424 * Set the publicly exported filesystem (WebNFS). Currently, only 2425 * one public filesystem is possible in the spec (RFC 2054 and 2055) 2426 */ 2427 int 2428 vfs_setpublicfs(mp, nep, argp) 2429 struct mount *mp; 2430 struct netexport *nep; 2431 struct export_args *argp; 2432 { 2433 int error; 2434 struct vnode *rvp; 2435 char *cp; 2436 2437 /* 2438 * mp == NULL -> invalidate the current info, the FS is 2439 * no longer exported. May be called from either vfs_export 2440 * or unmount, so check if it hasn't already been done. 2441 */ 2442 if (mp == NULL) { 2443 if (nfs_pub.np_valid) { 2444 nfs_pub.np_valid = 0; 2445 if (nfs_pub.np_index != NULL) { 2446 FREE(nfs_pub.np_index, M_TEMP); 2447 nfs_pub.np_index = NULL; 2448 } 2449 } 2450 return (0); 2451 } 2452 2453 /* 2454 * Only one allowed at a time. 2455 */ 2456 if (nfs_pub.np_valid != 0 && mp != nfs_pub.np_mount) 2457 return (EBUSY); 2458 2459 /* 2460 * Get real filehandle for root of exported FS. 2461 */ 2462 bzero((caddr_t)&nfs_pub.np_handle, sizeof(nfs_pub.np_handle)); 2463 nfs_pub.np_handle.fh_fsid = mp->mnt_stat.f_fsid; 2464 2465 if ((error = VFS_ROOT(mp, &rvp))) 2466 return (error); 2467 2468 if ((error = VFS_VPTOFH(rvp, &nfs_pub.np_handle.fh_fid))) 2469 return (error); 2470 2471 vput(rvp); 2472 2473 /* 2474 * If an indexfile was specified, pull it in. 2475 */ 2476 if (argp->ex_indexfile != NULL) { 2477 MALLOC(nfs_pub.np_index, char *, MAXNAMLEN + 1, M_TEMP, 2478 M_WAITOK); 2479 error = copyinstr(argp->ex_indexfile, nfs_pub.np_index, 2480 MAXNAMLEN, (size_t *)0); 2481 if (!error) { 2482 /* 2483 * Check for illegal filenames. 2484 */ 2485 for (cp = nfs_pub.np_index; *cp; cp++) { 2486 if (*cp == '/') { 2487 error = EINVAL; 2488 break; 2489 } 2490 } 2491 } 2492 if (error) { 2493 FREE(nfs_pub.np_index, M_TEMP); 2494 return (error); 2495 } 2496 } 2497 2498 nfs_pub.np_mount = mp; 2499 nfs_pub.np_valid = 1; 2500 return (0); 2501 } 2502 2503 struct netcred * 2504 vfs_export_lookup(mp, nep, nam) 2505 register struct mount *mp; 2506 struct netexport *nep; 2507 struct sockaddr *nam; 2508 { 2509 register struct netcred *np; 2510 register struct radix_node_head *rnh; 2511 struct sockaddr *saddr; 2512 2513 np = NULL; 2514 if (mp->mnt_flag & MNT_EXPORTED) { 2515 /* 2516 * Lookup in the export list first. 2517 */ 2518 if (nam != NULL) { 2519 saddr = nam; 2520 rnh = nep->ne_rtable[saddr->sa_family]; 2521 if (rnh != NULL) { 2522 np = (struct netcred *) 2523 (*rnh->rnh_matchaddr)((caddr_t)saddr, 2524 rnh); 2525 if (np && np->netc_rnodes->rn_flags & RNF_ROOT) 2526 np = NULL; 2527 } 2528 } 2529 /* 2530 * If no address match, use the default if it exists. 2531 */ 2532 if (np == NULL && mp->mnt_flag & MNT_DEFEXPORTED) 2533 np = &nep->ne_defexported; 2534 } 2535 return (np); 2536 } 2537 2538 /* 2539 * perform msync on all vnodes under a mount point 2540 * the mount point must be locked. 2541 */ 2542 void 2543 vfs_msync(struct mount *mp, int flags) { 2544 struct vnode *vp, *nvp; 2545 struct vm_object *obj; 2546 int anyio, tries; 2547 2548 tries = 5; 2549 loop: 2550 anyio = 0; 2551 for (vp = mp->mnt_vnodelist.lh_first; vp != NULL; vp = nvp) { 2552 2553 nvp = vp->v_mntvnodes.le_next; 2554 2555 if (vp->v_mount != mp) { 2556 goto loop; 2557 } 2558 2559 if (vp->v_flag & VXLOCK) /* XXX: what if MNT_WAIT? */ 2560 continue; 2561 2562 if (flags != MNT_WAIT) { 2563 obj = vp->v_object; 2564 if (obj == NULL || (obj->flags & OBJ_MIGHTBEDIRTY) == 0) 2565 continue; 2566 if (VOP_ISLOCKED(vp)) 2567 continue; 2568 } 2569 2570 simple_lock(&vp->v_interlock); 2571 if (vp->v_object && 2572 (vp->v_object->flags & OBJ_MIGHTBEDIRTY)) { 2573 if (!vget(vp, 2574 LK_INTERLOCK | LK_EXCLUSIVE | LK_RETRY | LK_NOOBJ, curproc)) { 2575 if (vp->v_object) { 2576 vm_object_page_clean(vp->v_object, 0, 0, flags == MNT_WAIT ? OBJPC_SYNC : 0); 2577 anyio = 1; 2578 } 2579 vput(vp); 2580 } 2581 } else { 2582 simple_unlock(&vp->v_interlock); 2583 } 2584 } 2585 if (anyio && (--tries > 0)) 2586 goto loop; 2587 } 2588 2589 /* 2590 * Create the VM object needed for VMIO and mmap support. This 2591 * is done for all VREG files in the system. Some filesystems might 2592 * afford the additional metadata buffering capability of the 2593 * VMIO code by making the device node be VMIO mode also. 2594 * 2595 * vp must be locked when vfs_object_create is called. 2596 */ 2597 int 2598 vfs_object_create(vp, p, cred) 2599 struct vnode *vp; 2600 struct proc *p; 2601 struct ucred *cred; 2602 { 2603 struct vattr vat; 2604 vm_object_t object; 2605 int error = 0; 2606 2607 if ((vp->v_type != VREG) && (vp->v_type != VBLK)) 2608 return 0; 2609 2610 retry: 2611 if ((object = vp->v_object) == NULL) { 2612 if (vp->v_type == VREG) { 2613 if ((error = VOP_GETATTR(vp, &vat, cred, p)) != 0) 2614 goto retn; 2615 object = vnode_pager_alloc(vp, vat.va_size, 0, 0); 2616 } else if (bdevsw(vp->v_rdev) != NULL) { 2617 /* 2618 * This simply allocates the biggest object possible 2619 * for a VBLK vnode. This should be fixed, but doesn't 2620 * cause any problems (yet). 2621 */ 2622 object = vnode_pager_alloc(vp, IDX_TO_OFF(INT_MAX), 0, 0); 2623 } else { 2624 goto retn; 2625 } 2626 /* 2627 * Dereference the reference we just created. This assumes 2628 * that the object is associated with the vp. 2629 */ 2630 object->ref_count--; 2631 vp->v_usecount--; 2632 } else { 2633 if (object->flags & OBJ_DEAD) { 2634 VOP_UNLOCK(vp, 0, p); 2635 tsleep(object, PVM, "vodead", 0); 2636 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p); 2637 goto retry; 2638 } 2639 } 2640 2641 KASSERT(vp->v_object != NULL, ("vfs_object_create: NULL object")); 2642 vp->v_flag |= VOBJBUF; 2643 2644 retn: 2645 return error; 2646 } 2647 2648 static void 2649 vfree(vp) 2650 struct vnode *vp; 2651 { 2652 int s; 2653 2654 s = splbio(); 2655 simple_lock(&vnode_free_list_slock); 2656 if (vp->v_flag & VTBFREE) { 2657 TAILQ_REMOVE(&vnode_tobefree_list, vp, v_freelist); 2658 vp->v_flag &= ~VTBFREE; 2659 } 2660 if (vp->v_flag & VAGE) { 2661 TAILQ_INSERT_HEAD(&vnode_free_list, vp, v_freelist); 2662 } else { 2663 TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_freelist); 2664 } 2665 freevnodes++; 2666 simple_unlock(&vnode_free_list_slock); 2667 vp->v_flag &= ~VAGE; 2668 vp->v_flag |= VFREE; 2669 splx(s); 2670 } 2671 2672 void 2673 vbusy(vp) 2674 struct vnode *vp; 2675 { 2676 int s; 2677 2678 s = splbio(); 2679 simple_lock(&vnode_free_list_slock); 2680 if (vp->v_flag & VTBFREE) { 2681 TAILQ_REMOVE(&vnode_tobefree_list, vp, v_freelist); 2682 vp->v_flag &= ~VTBFREE; 2683 } else { 2684 TAILQ_REMOVE(&vnode_free_list, vp, v_freelist); 2685 freevnodes--; 2686 } 2687 simple_unlock(&vnode_free_list_slock); 2688 vp->v_flag &= ~(VFREE|VAGE); 2689 splx(s); 2690 } 2691 2692 /* 2693 * Record a process's interest in events which might happen to 2694 * a vnode. Because poll uses the historic select-style interface 2695 * internally, this routine serves as both the ``check for any 2696 * pending events'' and the ``record my interest in future events'' 2697 * functions. (These are done together, while the lock is held, 2698 * to avoid race conditions.) 2699 */ 2700 int 2701 vn_pollrecord(vp, p, events) 2702 struct vnode *vp; 2703 struct proc *p; 2704 short events; 2705 { 2706 simple_lock(&vp->v_pollinfo.vpi_lock); 2707 if (vp->v_pollinfo.vpi_revents & events) { 2708 /* 2709 * This leaves events we are not interested 2710 * in available for the other process which 2711 * which presumably had requested them 2712 * (otherwise they would never have been 2713 * recorded). 2714 */ 2715 events &= vp->v_pollinfo.vpi_revents; 2716 vp->v_pollinfo.vpi_revents &= ~events; 2717 2718 simple_unlock(&vp->v_pollinfo.vpi_lock); 2719 return events; 2720 } 2721 vp->v_pollinfo.vpi_events |= events; 2722 selrecord(p, &vp->v_pollinfo.vpi_selinfo); 2723 simple_unlock(&vp->v_pollinfo.vpi_lock); 2724 return 0; 2725 } 2726 2727 /* 2728 * Note the occurrence of an event. If the VN_POLLEVENT macro is used, 2729 * it is possible for us to miss an event due to race conditions, but 2730 * that condition is expected to be rare, so for the moment it is the 2731 * preferred interface. 2732 */ 2733 void 2734 vn_pollevent(vp, events) 2735 struct vnode *vp; 2736 short events; 2737 { 2738 simple_lock(&vp->v_pollinfo.vpi_lock); 2739 if (vp->v_pollinfo.vpi_events & events) { 2740 /* 2741 * We clear vpi_events so that we don't 2742 * call selwakeup() twice if two events are 2743 * posted before the polling process(es) is 2744 * awakened. This also ensures that we take at 2745 * most one selwakeup() if the polling process 2746 * is no longer interested. However, it does 2747 * mean that only one event can be noticed at 2748 * a time. (Perhaps we should only clear those 2749 * event bits which we note?) XXX 2750 */ 2751 vp->v_pollinfo.vpi_events = 0; /* &= ~events ??? */ 2752 vp->v_pollinfo.vpi_revents |= events; 2753 selwakeup(&vp->v_pollinfo.vpi_selinfo); 2754 } 2755 simple_unlock(&vp->v_pollinfo.vpi_lock); 2756 } 2757 2758 /* 2759 * Wake up anyone polling on vp because it is being revoked. 2760 * This depends on dead_poll() returning POLLHUP for correct 2761 * behavior. 2762 */ 2763 void 2764 vn_pollgone(vp) 2765 struct vnode *vp; 2766 { 2767 simple_lock(&vp->v_pollinfo.vpi_lock); 2768 if (vp->v_pollinfo.vpi_events) { 2769 vp->v_pollinfo.vpi_events = 0; 2770 selwakeup(&vp->v_pollinfo.vpi_selinfo); 2771 } 2772 simple_unlock(&vp->v_pollinfo.vpi_lock); 2773 } 2774 2775 2776 2777 /* 2778 * Routine to create and manage a filesystem syncer vnode. 2779 */ 2780 #define sync_close ((int (*) __P((struct vop_close_args *)))nullop) 2781 static int sync_fsync __P((struct vop_fsync_args *)); 2782 static int sync_inactive __P((struct vop_inactive_args *)); 2783 static int sync_reclaim __P((struct vop_reclaim_args *)); 2784 #define sync_lock ((int (*) __P((struct vop_lock_args *)))vop_nolock) 2785 #define sync_unlock ((int (*) __P((struct vop_unlock_args *)))vop_nounlock) 2786 static int sync_print __P((struct vop_print_args *)); 2787 #define sync_islocked ((int(*) __P((struct vop_islocked_args *)))vop_noislocked) 2788 2789 static vop_t **sync_vnodeop_p; 2790 static struct vnodeopv_entry_desc sync_vnodeop_entries[] = { 2791 { &vop_default_desc, (vop_t *) vop_eopnotsupp }, 2792 { &vop_close_desc, (vop_t *) sync_close }, /* close */ 2793 { &vop_fsync_desc, (vop_t *) sync_fsync }, /* fsync */ 2794 { &vop_inactive_desc, (vop_t *) sync_inactive }, /* inactive */ 2795 { &vop_reclaim_desc, (vop_t *) sync_reclaim }, /* reclaim */ 2796 { &vop_lock_desc, (vop_t *) sync_lock }, /* lock */ 2797 { &vop_unlock_desc, (vop_t *) sync_unlock }, /* unlock */ 2798 { &vop_print_desc, (vop_t *) sync_print }, /* print */ 2799 { &vop_islocked_desc, (vop_t *) sync_islocked }, /* islocked */ 2800 { NULL, NULL } 2801 }; 2802 static struct vnodeopv_desc sync_vnodeop_opv_desc = 2803 { &sync_vnodeop_p, sync_vnodeop_entries }; 2804 2805 VNODEOP_SET(sync_vnodeop_opv_desc); 2806 2807 /* 2808 * Create a new filesystem syncer vnode for the specified mount point. 2809 */ 2810 int 2811 vfs_allocate_syncvnode(mp) 2812 struct mount *mp; 2813 { 2814 struct vnode *vp; 2815 static long start, incr, next; 2816 int error; 2817 2818 /* Allocate a new vnode */ 2819 if ((error = getnewvnode(VT_VFS, mp, sync_vnodeop_p, &vp)) != 0) { 2820 mp->mnt_syncer = NULL; 2821 return (error); 2822 } 2823 vp->v_type = VNON; 2824 /* 2825 * Place the vnode onto the syncer worklist. We attempt to 2826 * scatter them about on the list so that they will go off 2827 * at evenly distributed times even if all the filesystems 2828 * are mounted at once. 2829 */ 2830 next += incr; 2831 if (next == 0 || next > syncer_maxdelay) { 2832 start /= 2; 2833 incr /= 2; 2834 if (start == 0) { 2835 start = syncer_maxdelay / 2; 2836 incr = syncer_maxdelay; 2837 } 2838 next = start; 2839 } 2840 vn_syncer_add_to_worklist(vp, syncdelay > 0 ? next % syncdelay : 0); 2841 mp->mnt_syncer = vp; 2842 return (0); 2843 } 2844 2845 /* 2846 * Do a lazy sync of the filesystem. 2847 */ 2848 static int 2849 sync_fsync(ap) 2850 struct vop_fsync_args /* { 2851 struct vnode *a_vp; 2852 struct ucred *a_cred; 2853 int a_waitfor; 2854 struct proc *a_p; 2855 } */ *ap; 2856 { 2857 struct vnode *syncvp = ap->a_vp; 2858 struct mount *mp = syncvp->v_mount; 2859 struct proc *p = ap->a_p; 2860 int asyncflag; 2861 2862 /* 2863 * We only need to do something if this is a lazy evaluation. 2864 */ 2865 if (ap->a_waitfor != MNT_LAZY) 2866 return (0); 2867 2868 /* 2869 * Move ourselves to the back of the sync list. 2870 */ 2871 vn_syncer_add_to_worklist(syncvp, syncdelay); 2872 2873 /* 2874 * Walk the list of vnodes pushing all that are dirty and 2875 * not already on the sync list. 2876 */ 2877 simple_lock(&mountlist_slock); 2878 if (vfs_busy(mp, LK_EXCLUSIVE | LK_NOWAIT, &mountlist_slock, p) != 0) { 2879 simple_unlock(&mountlist_slock); 2880 return (0); 2881 } 2882 asyncflag = mp->mnt_flag & MNT_ASYNC; 2883 mp->mnt_flag &= ~MNT_ASYNC; 2884 vfs_msync(mp, MNT_NOWAIT); 2885 VFS_SYNC(mp, MNT_LAZY, ap->a_cred, p); 2886 if (asyncflag) 2887 mp->mnt_flag |= MNT_ASYNC; 2888 vfs_unbusy(mp, p); 2889 return (0); 2890 } 2891 2892 /* 2893 * The syncer vnode is no referenced. 2894 */ 2895 static int 2896 sync_inactive(ap) 2897 struct vop_inactive_args /* { 2898 struct vnode *a_vp; 2899 struct proc *a_p; 2900 } */ *ap; 2901 { 2902 2903 vgone(ap->a_vp); 2904 return (0); 2905 } 2906 2907 /* 2908 * The syncer vnode is no longer needed and is being decommissioned. 2909 * 2910 * Modifications to the worklist must be protected at splbio(). 2911 */ 2912 static int 2913 sync_reclaim(ap) 2914 struct vop_reclaim_args /* { 2915 struct vnode *a_vp; 2916 } */ *ap; 2917 { 2918 struct vnode *vp = ap->a_vp; 2919 int s; 2920 2921 s = splbio(); 2922 vp->v_mount->mnt_syncer = NULL; 2923 if (vp->v_flag & VONWORKLST) { 2924 LIST_REMOVE(vp, v_synclist); 2925 vp->v_flag &= ~VONWORKLST; 2926 } 2927 splx(s); 2928 2929 return (0); 2930 } 2931 2932 /* 2933 * Print out a syncer vnode. 2934 */ 2935 static int 2936 sync_print(ap) 2937 struct vop_print_args /* { 2938 struct vnode *a_vp; 2939 } */ *ap; 2940 { 2941 struct vnode *vp = ap->a_vp; 2942 2943 printf("syncer vnode"); 2944 if (vp->v_vnlock != NULL) 2945 lockmgr_printinfo(vp->v_vnlock); 2946 printf("\n"); 2947 return (0); 2948 } 2949