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