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