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/buf.h> 50 #include <sys/conf.h> 51 #include <sys/dirent.h> 52 #include <sys/domain.h> 53 #include <sys/eventhandler.h> 54 #include <sys/fcntl.h> 55 #include <sys/kernel.h> 56 #include <sys/kthread.h> 57 #include <sys/malloc.h> 58 #include <sys/mount.h> 59 #include <sys/namei.h> 60 #include <sys/proc.h> 61 #include <sys/reboot.h> 62 #include <sys/socket.h> 63 #include <sys/stat.h> 64 #include <sys/sysctl.h> 65 #include <sys/vmmeter.h> 66 #include <sys/vnode.h> 67 68 #include <machine/limits.h> 69 70 #include <vm/vm.h> 71 #include <vm/vm_object.h> 72 #include <vm/vm_extern.h> 73 #include <vm/pmap.h> 74 #include <vm/vm_map.h> 75 #include <vm/vm_page.h> 76 #include <vm/vm_pager.h> 77 #include <vm/vnode_pager.h> 78 #include <vm/vm_zone.h> 79 80 static MALLOC_DEFINE(M_NETADDR, "Export Host", "Export host address structure"); 81 82 static void insmntque __P((struct vnode *vp, struct mount *mp)); 83 static void vclean __P((struct vnode *vp, int flags, struct proc *p)); 84 static void vfree __P((struct vnode *)); 85 static unsigned long numvnodes; 86 SYSCTL_INT(_debug, OID_AUTO, numvnodes, CTLFLAG_RD, &numvnodes, 0, ""); 87 88 enum vtype iftovt_tab[16] = { 89 VNON, VFIFO, VCHR, VNON, VDIR, VNON, VBLK, VNON, 90 VREG, VNON, VLNK, VNON, VSOCK, VNON, VNON, VBAD, 91 }; 92 int vttoif_tab[9] = { 93 0, S_IFREG, S_IFDIR, S_IFBLK, S_IFCHR, S_IFLNK, 94 S_IFSOCK, S_IFIFO, S_IFMT, 95 }; 96 97 static TAILQ_HEAD(freelst, vnode) vnode_free_list; /* vnode free list */ 98 struct tobefreelist vnode_tobefree_list; /* vnode free list */ 99 100 static u_long wantfreevnodes = 25; 101 SYSCTL_INT(_debug, OID_AUTO, wantfreevnodes, CTLFLAG_RW, &wantfreevnodes, 0, ""); 102 static u_long freevnodes = 0; 103 SYSCTL_INT(_debug, OID_AUTO, freevnodes, CTLFLAG_RD, &freevnodes, 0, ""); 104 105 static int reassignbufcalls; 106 SYSCTL_INT(_vfs, OID_AUTO, reassignbufcalls, CTLFLAG_RW, &reassignbufcalls, 0, ""); 107 static int reassignbufloops; 108 SYSCTL_INT(_vfs, OID_AUTO, reassignbufloops, CTLFLAG_RW, &reassignbufloops, 0, ""); 109 static int reassignbufsortgood; 110 SYSCTL_INT(_vfs, OID_AUTO, reassignbufsortgood, CTLFLAG_RW, &reassignbufsortgood, 0, ""); 111 static int reassignbufsortbad; 112 SYSCTL_INT(_vfs, OID_AUTO, reassignbufsortbad, CTLFLAG_RW, &reassignbufsortbad, 0, ""); 113 static int reassignbufmethod = 1; 114 SYSCTL_INT(_vfs, OID_AUTO, reassignbufmethod, CTLFLAG_RW, &reassignbufmethod, 0, ""); 115 116 #ifdef ENABLE_VFS_IOOPT 117 int vfs_ioopt = 0; 118 SYSCTL_INT(_vfs, OID_AUTO, ioopt, CTLFLAG_RW, &vfs_ioopt, 0, ""); 119 #endif 120 121 struct mntlist mountlist = TAILQ_HEAD_INITIALIZER(mountlist); /* mounted fs */ 122 struct simplelock mountlist_slock; 123 struct simplelock mntvnode_slock; 124 int nfs_mount_type = -1; 125 #ifndef NULL_SIMPLELOCKS 126 static struct simplelock mntid_slock; 127 static struct simplelock vnode_free_list_slock; 128 static struct simplelock spechash_slock; 129 #endif 130 struct nfs_public nfs_pub; /* publicly exported FS */ 131 static vm_zone_t vnode_zone; 132 133 /* 134 * The workitem queue. 135 */ 136 #define SYNCER_MAXDELAY 32 137 static int syncer_maxdelay = SYNCER_MAXDELAY; /* maximum delay time */ 138 time_t syncdelay = 30; /* max time to delay syncing data */ 139 time_t filedelay = 30; /* time to delay syncing files */ 140 SYSCTL_INT(_kern, OID_AUTO, filedelay, CTLFLAG_RW, &filedelay, 0, ""); 141 time_t dirdelay = 29; /* time to delay syncing directories */ 142 SYSCTL_INT(_kern, OID_AUTO, dirdelay, CTLFLAG_RW, &dirdelay, 0, ""); 143 time_t metadelay = 28; /* time to delay syncing metadata */ 144 SYSCTL_INT(_kern, OID_AUTO, metadelay, CTLFLAG_RW, &metadelay, 0, ""); 145 static int rushjob; /* number of slots to run ASAP */ 146 static int stat_rush_requests; /* number of times I/O speeded up */ 147 SYSCTL_INT(_debug, OID_AUTO, rush_requests, CTLFLAG_RW, &stat_rush_requests, 0, ""); 148 149 static int syncer_delayno = 0; 150 static long syncer_mask; 151 LIST_HEAD(synclist, vnode); 152 static struct synclist *syncer_workitem_pending; 153 154 int desiredvnodes; 155 SYSCTL_INT(_kern, KERN_MAXVNODES, maxvnodes, CTLFLAG_RW, 156 &desiredvnodes, 0, "Maximum number of vnodes"); 157 158 static void vfs_free_addrlist __P((struct netexport *nep)); 159 static int vfs_free_netcred __P((struct radix_node *rn, void *w)); 160 static int vfs_hang_addrlist __P((struct mount *mp, struct netexport *nep, 161 struct export_args *argp)); 162 163 /* 164 * Initialize the vnode management data structures. 165 */ 166 void 167 vntblinit() 168 { 169 170 desiredvnodes = maxproc + cnt.v_page_count / 4; 171 simple_lock_init(&mntvnode_slock); 172 simple_lock_init(&mntid_slock); 173 simple_lock_init(&spechash_slock); 174 TAILQ_INIT(&vnode_free_list); 175 TAILQ_INIT(&vnode_tobefree_list); 176 simple_lock_init(&vnode_free_list_slock); 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 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 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. Try to make its val[0] unique, since this value 332 * will be used to create fake device numbers for stat(). Also try (but 333 * not so hard) make its val[0] unique mod 2^16, since some emulators only 334 * support 16-bit device numbers. We end up with unique val[0]'s for the 335 * first 2^16 calls and unique val[0]'s mod 2^16 for the first 2^8 calls. 336 * 337 * Keep in mind that several mounts may be running in parallel. Starting 338 * the search one past where the previous search terminated is both a 339 * micro-optimization and a defense against returning the same fsid to 340 * different mounts. 341 */ 342 void 343 vfs_getnewfsid(mp) 344 struct mount *mp; 345 { 346 static u_int16_t mntid_base; 347 fsid_t tfsid; 348 int mtype; 349 350 simple_lock(&mntid_slock); 351 mtype = mp->mnt_vfc->vfc_typenum; 352 tfsid.val[1] = mtype; 353 mtype = (mtype & 0xFF) << 16; 354 for (;;) { 355 tfsid.val[0] = makeudev(255, mtype | mntid_base++); 356 if (vfs_getvfs(&tfsid) == NULL) 357 break; 358 } 359 mp->mnt_stat.f_fsid.val[0] = tfsid.val[0]; 360 mp->mnt_stat.f_fsid.val[1] = tfsid.val[1]; 361 simple_unlock(&mntid_slock); 362 } 363 364 /* 365 * Knob to control the precision of file timestamps: 366 * 367 * 0 = seconds only; nanoseconds zeroed. 368 * 1 = seconds and nanoseconds, accurate within 1/HZ. 369 * 2 = seconds and nanoseconds, truncated to microseconds. 370 * >=3 = seconds and nanoseconds, maximum precision. 371 */ 372 enum { TSP_SEC, TSP_HZ, TSP_USEC, TSP_NSEC }; 373 374 static int timestamp_precision = TSP_SEC; 375 SYSCTL_INT(_vfs, OID_AUTO, timestamp_precision, CTLFLAG_RW, 376 ×tamp_precision, 0, ""); 377 378 /* 379 * Get a current timestamp. 380 */ 381 void 382 vfs_timestamp(tsp) 383 struct timespec *tsp; 384 { 385 struct timeval tv; 386 387 switch (timestamp_precision) { 388 case TSP_SEC: 389 tsp->tv_sec = time_second; 390 tsp->tv_nsec = 0; 391 break; 392 case TSP_HZ: 393 getnanotime(tsp); 394 break; 395 case TSP_USEC: 396 microtime(&tv); 397 TIMEVAL_TO_TIMESPEC(&tv, tsp); 398 break; 399 case TSP_NSEC: 400 default: 401 nanotime(tsp); 402 break; 403 } 404 } 405 406 /* 407 * Set vnode attributes to VNOVAL 408 */ 409 void 410 vattr_null(vap) 411 register struct vattr *vap; 412 { 413 414 vap->va_type = VNON; 415 vap->va_size = VNOVAL; 416 vap->va_bytes = VNOVAL; 417 vap->va_mode = VNOVAL; 418 vap->va_nlink = VNOVAL; 419 vap->va_uid = VNOVAL; 420 vap->va_gid = VNOVAL; 421 vap->va_fsid = VNOVAL; 422 vap->va_fileid = VNOVAL; 423 vap->va_blocksize = VNOVAL; 424 vap->va_rdev = VNOVAL; 425 vap->va_atime.tv_sec = VNOVAL; 426 vap->va_atime.tv_nsec = VNOVAL; 427 vap->va_mtime.tv_sec = VNOVAL; 428 vap->va_mtime.tv_nsec = VNOVAL; 429 vap->va_ctime.tv_sec = VNOVAL; 430 vap->va_ctime.tv_nsec = VNOVAL; 431 vap->va_flags = VNOVAL; 432 vap->va_gen = VNOVAL; 433 vap->va_vaflags = 0; 434 } 435 436 /* 437 * Routines having to do with the management of the vnode table. 438 */ 439 extern vop_t **dead_vnodeop_p; 440 441 /* 442 * Return the next vnode from the free list. 443 */ 444 int 445 getnewvnode(tag, mp, vops, vpp) 446 enum vtagtype tag; 447 struct mount *mp; 448 vop_t **vops; 449 struct vnode **vpp; 450 { 451 int s; 452 struct proc *p = curproc; /* XXX */ 453 struct vnode *vp, *tvp, *nvp; 454 vm_object_t object; 455 TAILQ_HEAD(freelst, vnode) vnode_tmp_list; 456 457 /* 458 * We take the least recently used vnode from the freelist 459 * if we can get it and it has no cached pages, and no 460 * namecache entries are relative to it. 461 * Otherwise we allocate a new vnode 462 */ 463 464 s = splbio(); 465 simple_lock(&vnode_free_list_slock); 466 TAILQ_INIT(&vnode_tmp_list); 467 468 for (vp = TAILQ_FIRST(&vnode_tobefree_list); vp; vp = nvp) { 469 nvp = TAILQ_NEXT(vp, v_freelist); 470 TAILQ_REMOVE(&vnode_tobefree_list, vp, v_freelist); 471 if (vp->v_flag & VAGE) { 472 TAILQ_INSERT_HEAD(&vnode_free_list, vp, v_freelist); 473 } else { 474 TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_freelist); 475 } 476 vp->v_flag &= ~(VTBFREE|VAGE); 477 vp->v_flag |= VFREE; 478 if (vp->v_usecount) 479 panic("tobe free vnode isn't"); 480 freevnodes++; 481 } 482 483 if (wantfreevnodes && freevnodes < wantfreevnodes) { 484 vp = NULL; 485 } else if (!wantfreevnodes && freevnodes <= desiredvnodes) { 486 /* 487 * XXX: this is only here to be backwards compatible 488 */ 489 vp = NULL; 490 } else { 491 for (vp = TAILQ_FIRST(&vnode_free_list); vp; vp = nvp) { 492 nvp = TAILQ_NEXT(vp, v_freelist); 493 if (!simple_lock_try(&vp->v_interlock)) 494 continue; 495 if (vp->v_usecount) 496 panic("free vnode isn't"); 497 498 object = vp->v_object; 499 if (object && (object->resident_page_count || object->ref_count)) { 500 printf("object inconsistant state: RPC: %d, RC: %d\n", 501 object->resident_page_count, object->ref_count); 502 /* Don't recycle if it's caching some pages */ 503 TAILQ_REMOVE(&vnode_free_list, vp, v_freelist); 504 TAILQ_INSERT_TAIL(&vnode_tmp_list, vp, v_freelist); 505 continue; 506 } else if (LIST_FIRST(&vp->v_cache_src)) { 507 /* Don't recycle if active in the namecache */ 508 simple_unlock(&vp->v_interlock); 509 continue; 510 } else { 511 break; 512 } 513 } 514 } 515 516 for (tvp = TAILQ_FIRST(&vnode_tmp_list); tvp; tvp = nvp) { 517 nvp = TAILQ_NEXT(tvp, v_freelist); 518 TAILQ_REMOVE(&vnode_tmp_list, tvp, v_freelist); 519 TAILQ_INSERT_TAIL(&vnode_free_list, tvp, v_freelist); 520 simple_unlock(&tvp->v_interlock); 521 } 522 523 if (vp) { 524 vp->v_flag |= VDOOMED; 525 TAILQ_REMOVE(&vnode_free_list, vp, v_freelist); 526 freevnodes--; 527 simple_unlock(&vnode_free_list_slock); 528 cache_purge(vp); 529 vp->v_lease = NULL; 530 if (vp->v_type != VBAD) { 531 vgonel(vp, p); 532 } else { 533 simple_unlock(&vp->v_interlock); 534 } 535 536 #ifdef INVARIANTS 537 { 538 int s; 539 540 if (vp->v_data) 541 panic("cleaned vnode isn't"); 542 s = splbio(); 543 if (vp->v_numoutput) 544 panic("Clean vnode has pending I/O's"); 545 splx(s); 546 } 547 #endif 548 vp->v_flag = 0; 549 vp->v_lastw = 0; 550 vp->v_lasta = 0; 551 vp->v_cstart = 0; 552 vp->v_clen = 0; 553 vp->v_socket = 0; 554 vp->v_writecount = 0; /* XXX */ 555 } else { 556 simple_unlock(&vnode_free_list_slock); 557 vp = (struct vnode *) zalloc(vnode_zone); 558 bzero((char *) vp, sizeof *vp); 559 simple_lock_init(&vp->v_interlock); 560 vp->v_dd = vp; 561 cache_purge(vp); 562 LIST_INIT(&vp->v_cache_src); 563 TAILQ_INIT(&vp->v_cache_dst); 564 numvnodes++; 565 } 566 567 TAILQ_INIT(&vp->v_cleanblkhd); 568 TAILQ_INIT(&vp->v_dirtyblkhd); 569 vp->v_type = VNON; 570 vp->v_tag = tag; 571 vp->v_op = vops; 572 insmntque(vp, mp); 573 *vpp = vp; 574 vp->v_usecount = 1; 575 vp->v_data = 0; 576 splx(s); 577 578 vfs_object_create(vp, p, p->p_ucred); 579 return (0); 580 } 581 582 /* 583 * Move a vnode from one mount queue to another. 584 */ 585 static void 586 insmntque(vp, mp) 587 register struct vnode *vp; 588 register struct mount *mp; 589 { 590 591 simple_lock(&mntvnode_slock); 592 /* 593 * Delete from old mount point vnode list, if on one. 594 */ 595 if (vp->v_mount != NULL) 596 LIST_REMOVE(vp, v_mntvnodes); 597 /* 598 * Insert into list of vnodes for the new mount point, if available. 599 */ 600 if ((vp->v_mount = mp) == NULL) { 601 simple_unlock(&mntvnode_slock); 602 return; 603 } 604 LIST_INSERT_HEAD(&mp->mnt_vnodelist, vp, v_mntvnodes); 605 simple_unlock(&mntvnode_slock); 606 } 607 608 /* 609 * Update outstanding I/O count and do wakeup if requested. 610 */ 611 void 612 vwakeup(bp) 613 register struct buf *bp; 614 { 615 register struct vnode *vp; 616 617 bp->b_flags &= ~B_WRITEINPROG; 618 if ((vp = bp->b_vp)) { 619 vp->v_numoutput--; 620 if (vp->v_numoutput < 0) 621 panic("vwakeup: neg numoutput"); 622 if ((vp->v_numoutput == 0) && (vp->v_flag & VBWAIT)) { 623 vp->v_flag &= ~VBWAIT; 624 wakeup((caddr_t) &vp->v_numoutput); 625 } 626 } 627 } 628 629 /* 630 * Flush out and invalidate all buffers associated with a vnode. 631 * Called with the underlying object locked. 632 */ 633 int 634 vinvalbuf(vp, flags, cred, p, slpflag, slptimeo) 635 register struct vnode *vp; 636 int flags; 637 struct ucred *cred; 638 struct proc *p; 639 int slpflag, slptimeo; 640 { 641 register struct buf *bp; 642 struct buf *nbp, *blist; 643 int s, error; 644 vm_object_t object; 645 646 if (flags & V_SAVE) { 647 s = splbio(); 648 while (vp->v_numoutput) { 649 vp->v_flag |= VBWAIT; 650 error = tsleep((caddr_t)&vp->v_numoutput, 651 slpflag | (PRIBIO + 1), "vinvlbuf", slptimeo); 652 if (error) { 653 splx(s); 654 return (error); 655 } 656 } 657 if (!TAILQ_EMPTY(&vp->v_dirtyblkhd)) { 658 splx(s); 659 if ((error = VOP_FSYNC(vp, cred, MNT_WAIT, p)) != 0) 660 return (error); 661 s = splbio(); 662 if (vp->v_numoutput > 0 || 663 !TAILQ_EMPTY(&vp->v_dirtyblkhd)) 664 panic("vinvalbuf: dirty bufs"); 665 } 666 splx(s); 667 } 668 s = splbio(); 669 for (;;) { 670 blist = TAILQ_FIRST(&vp->v_cleanblkhd); 671 if (!blist) 672 blist = TAILQ_FIRST(&vp->v_dirtyblkhd); 673 if (!blist) 674 break; 675 676 for (bp = blist; bp; bp = nbp) { 677 nbp = TAILQ_NEXT(bp, b_vnbufs); 678 if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_NOWAIT)) { 679 error = BUF_TIMELOCK(bp, 680 LK_EXCLUSIVE | LK_SLEEPFAIL, 681 "vinvalbuf", slpflag, slptimeo); 682 if (error == ENOLCK) 683 break; 684 splx(s); 685 return (error); 686 } 687 /* 688 * XXX Since there are no node locks for NFS, I 689 * believe there is a slight chance that a delayed 690 * write will occur while sleeping just above, so 691 * check for it. Note that vfs_bio_awrite expects 692 * buffers to reside on a queue, while VOP_BWRITE and 693 * brelse do not. 694 */ 695 if (((bp->b_flags & (B_DELWRI | B_INVAL)) == B_DELWRI) && 696 (flags & V_SAVE)) { 697 698 if (bp->b_vp == vp) { 699 if (bp->b_flags & B_CLUSTEROK) { 700 BUF_UNLOCK(bp); 701 vfs_bio_awrite(bp); 702 } else { 703 bremfree(bp); 704 bp->b_flags |= B_ASYNC; 705 BUF_WRITE(bp); 706 } 707 } else { 708 bremfree(bp); 709 (void) BUF_WRITE(bp); 710 } 711 break; 712 } 713 bremfree(bp); 714 bp->b_flags |= (B_INVAL | B_NOCACHE | B_RELBUF); 715 bp->b_flags &= ~B_ASYNC; 716 brelse(bp); 717 } 718 } 719 720 while (vp->v_numoutput > 0) { 721 vp->v_flag |= VBWAIT; 722 tsleep(&vp->v_numoutput, PVM, "vnvlbv", 0); 723 } 724 725 splx(s); 726 727 /* 728 * Destroy the copy in the VM cache, too. 729 */ 730 simple_lock(&vp->v_interlock); 731 object = vp->v_object; 732 if (object != NULL) { 733 vm_object_page_remove(object, 0, 0, 734 (flags & V_SAVE) ? TRUE : FALSE); 735 } 736 simple_unlock(&vp->v_interlock); 737 738 if (!TAILQ_EMPTY(&vp->v_dirtyblkhd) || !TAILQ_EMPTY(&vp->v_cleanblkhd)) 739 panic("vinvalbuf: flush failed"); 740 return (0); 741 } 742 743 /* 744 * Truncate a file's buffer and pages to a specified length. This 745 * is in lieu of the old vinvalbuf mechanism, which performed unneeded 746 * sync activity. 747 */ 748 int 749 vtruncbuf(vp, cred, p, length, blksize) 750 register struct vnode *vp; 751 struct ucred *cred; 752 struct proc *p; 753 off_t length; 754 int blksize; 755 { 756 register struct buf *bp; 757 struct buf *nbp; 758 int s, anyfreed; 759 int trunclbn; 760 761 /* 762 * Round up to the *next* lbn. 763 */ 764 trunclbn = (length + blksize - 1) / blksize; 765 766 s = splbio(); 767 restart: 768 anyfreed = 1; 769 for (;anyfreed;) { 770 anyfreed = 0; 771 for (bp = TAILQ_FIRST(&vp->v_cleanblkhd); bp; bp = nbp) { 772 nbp = TAILQ_NEXT(bp, b_vnbufs); 773 if (bp->b_lblkno >= trunclbn) { 774 if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_NOWAIT)) { 775 BUF_LOCK(bp, LK_EXCLUSIVE|LK_SLEEPFAIL); 776 goto restart; 777 } else { 778 bremfree(bp); 779 bp->b_flags |= (B_INVAL | B_RELBUF); 780 bp->b_flags &= ~B_ASYNC; 781 brelse(bp); 782 anyfreed = 1; 783 } 784 if (nbp && 785 (((nbp->b_xflags & BX_VNCLEAN) == 0) || 786 (nbp->b_vp != vp) || 787 (nbp->b_flags & B_DELWRI))) { 788 goto restart; 789 } 790 } 791 } 792 793 for (bp = TAILQ_FIRST(&vp->v_dirtyblkhd); bp; bp = nbp) { 794 nbp = TAILQ_NEXT(bp, b_vnbufs); 795 if (bp->b_lblkno >= trunclbn) { 796 if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_NOWAIT)) { 797 BUF_LOCK(bp, LK_EXCLUSIVE|LK_SLEEPFAIL); 798 goto restart; 799 } else { 800 bremfree(bp); 801 bp->b_flags |= (B_INVAL | B_RELBUF); 802 bp->b_flags &= ~B_ASYNC; 803 brelse(bp); 804 anyfreed = 1; 805 } 806 if (nbp && 807 (((nbp->b_xflags & BX_VNDIRTY) == 0) || 808 (nbp->b_vp != vp) || 809 (nbp->b_flags & B_DELWRI) == 0)) { 810 goto restart; 811 } 812 } 813 } 814 } 815 816 if (length > 0) { 817 restartsync: 818 for (bp = TAILQ_FIRST(&vp->v_dirtyblkhd); bp; bp = nbp) { 819 nbp = TAILQ_NEXT(bp, b_vnbufs); 820 if ((bp->b_flags & B_DELWRI) && (bp->b_lblkno < 0)) { 821 if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_NOWAIT)) { 822 BUF_LOCK(bp, LK_EXCLUSIVE|LK_SLEEPFAIL); 823 goto restart; 824 } else { 825 bremfree(bp); 826 if (bp->b_vp == vp) { 827 bp->b_flags |= B_ASYNC; 828 } else { 829 bp->b_flags &= ~B_ASYNC; 830 } 831 BUF_WRITE(bp); 832 } 833 goto restartsync; 834 } 835 836 } 837 } 838 839 while (vp->v_numoutput > 0) { 840 vp->v_flag |= VBWAIT; 841 tsleep(&vp->v_numoutput, PVM, "vbtrunc", 0); 842 } 843 844 splx(s); 845 846 vnode_pager_setsize(vp, length); 847 848 return (0); 849 } 850 851 /* 852 * Associate a buffer with a vnode. 853 */ 854 void 855 bgetvp(vp, bp) 856 register struct vnode *vp; 857 register struct buf *bp; 858 { 859 int s; 860 861 KASSERT(bp->b_vp == NULL, ("bgetvp: not free")); 862 863 vhold(vp); 864 bp->b_vp = vp; 865 bp->b_dev = vn_todev(vp); 866 /* 867 * Insert onto list for new vnode. 868 */ 869 s = splbio(); 870 bp->b_xflags |= BX_VNCLEAN; 871 bp->b_xflags &= ~BX_VNDIRTY; 872 TAILQ_INSERT_TAIL(&vp->v_cleanblkhd, bp, b_vnbufs); 873 splx(s); 874 } 875 876 /* 877 * Disassociate a buffer from a vnode. 878 */ 879 void 880 brelvp(bp) 881 register struct buf *bp; 882 { 883 struct vnode *vp; 884 struct buflists *listheadp; 885 int s; 886 887 KASSERT(bp->b_vp != NULL, ("brelvp: NULL")); 888 889 /* 890 * Delete from old vnode list, if on one. 891 */ 892 vp = bp->b_vp; 893 s = splbio(); 894 if (bp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN)) { 895 if (bp->b_xflags & BX_VNDIRTY) 896 listheadp = &vp->v_dirtyblkhd; 897 else 898 listheadp = &vp->v_cleanblkhd; 899 TAILQ_REMOVE(listheadp, bp, b_vnbufs); 900 bp->b_xflags &= ~(BX_VNDIRTY | BX_VNCLEAN); 901 } 902 if ((vp->v_flag & VONWORKLST) && TAILQ_EMPTY(&vp->v_dirtyblkhd)) { 903 vp->v_flag &= ~VONWORKLST; 904 LIST_REMOVE(vp, v_synclist); 905 } 906 splx(s); 907 bp->b_vp = (struct vnode *) 0; 908 vdrop(vp); 909 } 910 911 /* 912 * The workitem queue. 913 * 914 * It is useful to delay writes of file data and filesystem metadata 915 * for tens of seconds so that quickly created and deleted files need 916 * not waste disk bandwidth being created and removed. To realize this, 917 * we append vnodes to a "workitem" queue. When running with a soft 918 * updates implementation, most pending metadata dependencies should 919 * not wait for more than a few seconds. Thus, mounted on block devices 920 * are delayed only about a half the time that file data is delayed. 921 * Similarly, directory updates are more critical, so are only delayed 922 * about a third the time that file data is delayed. Thus, there are 923 * SYNCER_MAXDELAY queues that are processed round-robin at a rate of 924 * one each second (driven off the filesystem syncer process). The 925 * syncer_delayno variable indicates the next queue that is to be processed. 926 * Items that need to be processed soon are placed in this queue: 927 * 928 * syncer_workitem_pending[syncer_delayno] 929 * 930 * A delay of fifteen seconds is done by placing the request fifteen 931 * entries later in the queue: 932 * 933 * syncer_workitem_pending[(syncer_delayno + 15) & syncer_mask] 934 * 935 */ 936 937 /* 938 * Add an item to the syncer work queue. 939 */ 940 static void 941 vn_syncer_add_to_worklist(struct vnode *vp, int delay) 942 { 943 int s, slot; 944 945 s = splbio(); 946 947 if (vp->v_flag & VONWORKLST) { 948 LIST_REMOVE(vp, v_synclist); 949 } 950 951 if (delay > syncer_maxdelay - 2) 952 delay = syncer_maxdelay - 2; 953 slot = (syncer_delayno + delay) & syncer_mask; 954 955 LIST_INSERT_HEAD(&syncer_workitem_pending[slot], vp, v_synclist); 956 vp->v_flag |= VONWORKLST; 957 splx(s); 958 } 959 960 struct proc *updateproc; 961 static void sched_sync __P((void)); 962 static struct kproc_desc up_kp = { 963 "syncer", 964 sched_sync, 965 &updateproc 966 }; 967 SYSINIT(syncer, SI_SUB_KTHREAD_UPDATE, SI_ORDER_FIRST, kproc_start, &up_kp) 968 969 /* 970 * System filesystem synchronizer daemon. 971 */ 972 void 973 sched_sync(void) 974 { 975 struct synclist *slp; 976 struct vnode *vp; 977 long starttime; 978 int s; 979 struct proc *p = updateproc; 980 981 EVENTHANDLER_REGISTER(shutdown_pre_sync, shutdown_kproc, p, 982 SHUTDOWN_PRI_LAST); 983 984 for (;;) { 985 kproc_suspend_loop(p); 986 987 starttime = time_second; 988 989 /* 990 * Push files whose dirty time has expired. Be careful 991 * of interrupt race on slp queue. 992 */ 993 s = splbio(); 994 slp = &syncer_workitem_pending[syncer_delayno]; 995 syncer_delayno += 1; 996 if (syncer_delayno == syncer_maxdelay) 997 syncer_delayno = 0; 998 splx(s); 999 1000 while ((vp = LIST_FIRST(slp)) != NULL) { 1001 if (VOP_ISLOCKED(vp, NULL) == 0) { 1002 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p); 1003 (void) VOP_FSYNC(vp, p->p_ucred, MNT_LAZY, p); 1004 VOP_UNLOCK(vp, 0, p); 1005 } 1006 s = splbio(); 1007 if (LIST_FIRST(slp) == vp) { 1008 /* 1009 * Note: v_tag VT_VFS vps can remain on the 1010 * worklist too with no dirty blocks, but 1011 * since sync_fsync() moves it to a different 1012 * slot we are safe. 1013 */ 1014 if (TAILQ_EMPTY(&vp->v_dirtyblkhd) && 1015 !vn_isdisk(vp, NULL)) 1016 panic("sched_sync: fsync failed vp %p tag %d", vp, vp->v_tag); 1017 /* 1018 * Put us back on the worklist. The worklist 1019 * routine will remove us from our current 1020 * position and then add us back in at a later 1021 * position. 1022 */ 1023 vn_syncer_add_to_worklist(vp, syncdelay); 1024 } 1025 splx(s); 1026 } 1027 1028 /* 1029 * Do soft update processing. 1030 */ 1031 if (bioops.io_sync) 1032 (*bioops.io_sync)(NULL); 1033 1034 /* 1035 * The variable rushjob allows the kernel to speed up the 1036 * processing of the filesystem syncer process. A rushjob 1037 * value of N tells the filesystem syncer to process the next 1038 * N seconds worth of work on its queue ASAP. Currently rushjob 1039 * is used by the soft update code to speed up the filesystem 1040 * syncer process when the incore state is getting so far 1041 * ahead of the disk that the kernel memory pool is being 1042 * threatened with exhaustion. 1043 */ 1044 if (rushjob > 0) { 1045 rushjob -= 1; 1046 continue; 1047 } 1048 /* 1049 * If it has taken us less than a second to process the 1050 * current work, then wait. Otherwise start right over 1051 * again. We can still lose time if any single round 1052 * takes more than two seconds, but it does not really 1053 * matter as we are just trying to generally pace the 1054 * filesystem activity. 1055 */ 1056 if (time_second == starttime) 1057 tsleep(&lbolt, PPAUSE, "syncer", 0); 1058 } 1059 } 1060 1061 /* 1062 * Request the syncer daemon to speed up its work. 1063 * We never push it to speed up more than half of its 1064 * normal turn time, otherwise it could take over the cpu. 1065 */ 1066 int 1067 speedup_syncer() 1068 { 1069 int s; 1070 1071 s = splhigh(); 1072 if (updateproc->p_wchan == &lbolt) 1073 setrunnable(updateproc); 1074 splx(s); 1075 if (rushjob < syncdelay / 2) { 1076 rushjob += 1; 1077 stat_rush_requests += 1; 1078 return (1); 1079 } 1080 return(0); 1081 } 1082 1083 /* 1084 * Associate a p-buffer with a vnode. 1085 * 1086 * Also sets B_PAGING flag to indicate that vnode is not fully associated 1087 * with the buffer. i.e. the bp has not been linked into the vnode or 1088 * ref-counted. 1089 */ 1090 void 1091 pbgetvp(vp, bp) 1092 register struct vnode *vp; 1093 register struct buf *bp; 1094 { 1095 1096 KASSERT(bp->b_vp == NULL, ("pbgetvp: not free")); 1097 1098 bp->b_vp = vp; 1099 bp->b_flags |= B_PAGING; 1100 bp->b_dev = vn_todev(vp); 1101 } 1102 1103 /* 1104 * Disassociate a p-buffer from a vnode. 1105 */ 1106 void 1107 pbrelvp(bp) 1108 register struct buf *bp; 1109 { 1110 1111 KASSERT(bp->b_vp != NULL, ("pbrelvp: NULL")); 1112 1113 /* XXX REMOVE ME */ 1114 if (bp->b_vnbufs.tqe_next != NULL) { 1115 panic( 1116 "relpbuf(): b_vp was probably reassignbuf()d %p %x", 1117 bp, 1118 (int)bp->b_flags 1119 ); 1120 } 1121 bp->b_vp = (struct vnode *) 0; 1122 bp->b_flags &= ~B_PAGING; 1123 } 1124 1125 void 1126 pbreassignbuf(bp, newvp) 1127 struct buf *bp; 1128 struct vnode *newvp; 1129 { 1130 if ((bp->b_flags & B_PAGING) == 0) { 1131 panic( 1132 "pbreassignbuf() on non phys bp %p", 1133 bp 1134 ); 1135 } 1136 bp->b_vp = newvp; 1137 } 1138 1139 /* 1140 * Reassign a buffer from one vnode to another. 1141 * Used to assign file specific control information 1142 * (indirect blocks) to the vnode to which they belong. 1143 */ 1144 void 1145 reassignbuf(bp, newvp) 1146 register struct buf *bp; 1147 register struct vnode *newvp; 1148 { 1149 struct buflists *listheadp; 1150 int delay; 1151 int s; 1152 1153 if (newvp == NULL) { 1154 printf("reassignbuf: NULL"); 1155 return; 1156 } 1157 ++reassignbufcalls; 1158 1159 /* 1160 * B_PAGING flagged buffers cannot be reassigned because their vp 1161 * is not fully linked in. 1162 */ 1163 if (bp->b_flags & B_PAGING) 1164 panic("cannot reassign paging buffer"); 1165 1166 s = splbio(); 1167 /* 1168 * Delete from old vnode list, if on one. 1169 */ 1170 if (bp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN)) { 1171 if (bp->b_xflags & BX_VNDIRTY) 1172 listheadp = &bp->b_vp->v_dirtyblkhd; 1173 else 1174 listheadp = &bp->b_vp->v_cleanblkhd; 1175 TAILQ_REMOVE(listheadp, bp, b_vnbufs); 1176 bp->b_xflags &= ~(BX_VNDIRTY | BX_VNCLEAN); 1177 if (bp->b_vp != newvp) { 1178 vdrop(bp->b_vp); 1179 bp->b_vp = NULL; /* for clarification */ 1180 } 1181 } 1182 /* 1183 * If dirty, put on list of dirty buffers; otherwise insert onto list 1184 * of clean buffers. 1185 */ 1186 if (bp->b_flags & B_DELWRI) { 1187 struct buf *tbp; 1188 1189 listheadp = &newvp->v_dirtyblkhd; 1190 if ((newvp->v_flag & VONWORKLST) == 0) { 1191 switch (newvp->v_type) { 1192 case VDIR: 1193 delay = dirdelay; 1194 break; 1195 case VCHR: 1196 case VBLK: 1197 if (newvp->v_specmountpoint != NULL) { 1198 delay = metadelay; 1199 break; 1200 } 1201 /* fall through */ 1202 default: 1203 delay = filedelay; 1204 } 1205 vn_syncer_add_to_worklist(newvp, delay); 1206 } 1207 bp->b_xflags |= BX_VNDIRTY; 1208 tbp = TAILQ_FIRST(listheadp); 1209 if (tbp == NULL || 1210 bp->b_lblkno == 0 || 1211 (bp->b_lblkno > 0 && tbp->b_lblkno < 0) || 1212 (bp->b_lblkno > 0 && bp->b_lblkno < tbp->b_lblkno)) { 1213 TAILQ_INSERT_HEAD(listheadp, bp, b_vnbufs); 1214 ++reassignbufsortgood; 1215 } else if (bp->b_lblkno < 0) { 1216 TAILQ_INSERT_TAIL(listheadp, bp, b_vnbufs); 1217 ++reassignbufsortgood; 1218 } else if (reassignbufmethod == 1) { 1219 /* 1220 * New sorting algorithm, only handle sequential case, 1221 * otherwise append to end (but before metadata) 1222 */ 1223 if ((tbp = gbincore(newvp, bp->b_lblkno - 1)) != NULL && 1224 (tbp->b_xflags & BX_VNDIRTY)) { 1225 /* 1226 * Found the best place to insert the buffer 1227 */ 1228 TAILQ_INSERT_AFTER(listheadp, tbp, bp, b_vnbufs); 1229 ++reassignbufsortgood; 1230 } else { 1231 /* 1232 * Missed, append to end, but before meta-data. 1233 * We know that the head buffer in the list is 1234 * not meta-data due to prior conditionals. 1235 * 1236 * Indirect effects: NFS second stage write 1237 * tends to wind up here, giving maximum 1238 * distance between the unstable write and the 1239 * commit rpc. 1240 */ 1241 tbp = TAILQ_LAST(listheadp, buflists); 1242 while (tbp && tbp->b_lblkno < 0) 1243 tbp = TAILQ_PREV(tbp, buflists, b_vnbufs); 1244 TAILQ_INSERT_AFTER(listheadp, tbp, 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 |= BX_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 = LIST_FIRST(&mp->mnt_vnodelist); 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 = LIST_NEXT(vp, v_mntvnodes); 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 /* 1700 * Inline copy of vrele() since VOP_INACTIVE 1701 * has already been called. 1702 */ 1703 simple_lock(&vp->v_interlock); 1704 if (--vp->v_usecount <= 0) { 1705 #ifdef DIAGNOSTIC 1706 if (vp->v_usecount < 0 || vp->v_writecount != 0) { 1707 vprint("vclean: bad ref count", vp); 1708 panic("vclean: ref cnt"); 1709 } 1710 #endif 1711 vfree(vp); 1712 } 1713 simple_unlock(&vp->v_interlock); 1714 } 1715 1716 cache_purge(vp); 1717 if (vp->v_vnlock) { 1718 FREE(vp->v_vnlock, M_VNODE); 1719 vp->v_vnlock = NULL; 1720 } 1721 1722 if (VSHOULDFREE(vp)) 1723 vfree(vp); 1724 1725 /* 1726 * Done with purge, notify sleepers of the grim news. 1727 */ 1728 vp->v_op = dead_vnodeop_p; 1729 vn_pollgone(vp); 1730 vp->v_tag = VT_NON; 1731 vp->v_flag &= ~VXLOCK; 1732 if (vp->v_flag & VXWANT) { 1733 vp->v_flag &= ~VXWANT; 1734 wakeup((caddr_t) vp); 1735 } 1736 } 1737 1738 /* 1739 * Eliminate all activity associated with the requested vnode 1740 * and with all vnodes aliased to the requested vnode. 1741 */ 1742 int 1743 vop_revoke(ap) 1744 struct vop_revoke_args /* { 1745 struct vnode *a_vp; 1746 int a_flags; 1747 } */ *ap; 1748 { 1749 struct vnode *vp, *vq; 1750 dev_t dev; 1751 1752 KASSERT((ap->a_flags & REVOKEALL) != 0, ("vop_revoke")); 1753 1754 vp = ap->a_vp; 1755 /* 1756 * If a vgone (or vclean) is already in progress, 1757 * wait until it is done and return. 1758 */ 1759 if (vp->v_flag & VXLOCK) { 1760 vp->v_flag |= VXWANT; 1761 simple_unlock(&vp->v_interlock); 1762 tsleep((caddr_t)vp, PINOD, "vop_revokeall", 0); 1763 return (0); 1764 } 1765 dev = vp->v_rdev; 1766 for (;;) { 1767 simple_lock(&spechash_slock); 1768 vq = SLIST_FIRST(&dev->si_hlist); 1769 simple_unlock(&spechash_slock); 1770 if (!vq) 1771 break; 1772 vgone(vq); 1773 } 1774 return (0); 1775 } 1776 1777 /* 1778 * Recycle an unused vnode to the front of the free list. 1779 * Release the passed interlock if the vnode will be recycled. 1780 */ 1781 int 1782 vrecycle(vp, inter_lkp, p) 1783 struct vnode *vp; 1784 struct simplelock *inter_lkp; 1785 struct proc *p; 1786 { 1787 1788 simple_lock(&vp->v_interlock); 1789 if (vp->v_usecount == 0) { 1790 if (inter_lkp) { 1791 simple_unlock(inter_lkp); 1792 } 1793 vgonel(vp, p); 1794 return (1); 1795 } 1796 simple_unlock(&vp->v_interlock); 1797 return (0); 1798 } 1799 1800 /* 1801 * Eliminate all activity associated with a vnode 1802 * in preparation for reuse. 1803 */ 1804 void 1805 vgone(vp) 1806 register struct vnode *vp; 1807 { 1808 struct proc *p = curproc; /* XXX */ 1809 1810 simple_lock(&vp->v_interlock); 1811 vgonel(vp, p); 1812 } 1813 1814 /* 1815 * vgone, with the vp interlock held. 1816 */ 1817 void 1818 vgonel(vp, p) 1819 struct vnode *vp; 1820 struct proc *p; 1821 { 1822 int s; 1823 1824 /* 1825 * If a vgone (or vclean) is already in progress, 1826 * wait until it is done and return. 1827 */ 1828 if (vp->v_flag & VXLOCK) { 1829 vp->v_flag |= VXWANT; 1830 simple_unlock(&vp->v_interlock); 1831 tsleep((caddr_t)vp, PINOD, "vgone", 0); 1832 return; 1833 } 1834 1835 /* 1836 * Clean out the filesystem specific data. 1837 */ 1838 vclean(vp, DOCLOSE, p); 1839 simple_lock(&vp->v_interlock); 1840 1841 /* 1842 * Delete from old mount point vnode list, if on one. 1843 */ 1844 if (vp->v_mount != NULL) 1845 insmntque(vp, (struct mount *)0); 1846 /* 1847 * If special device, remove it from special device alias list 1848 * if it is on one. 1849 */ 1850 if ((vp->v_type == VBLK || vp->v_type == VCHR) && vp->v_rdev != NULL) { 1851 simple_lock(&spechash_slock); 1852 SLIST_REMOVE(&vp->v_hashchain, vp, vnode, v_specnext); 1853 freedev(vp->v_rdev); 1854 simple_unlock(&spechash_slock); 1855 vp->v_rdev = NULL; 1856 } 1857 1858 /* 1859 * If it is on the freelist and not already at the head, 1860 * move it to the head of the list. The test of the back 1861 * pointer and the reference count of zero is because 1862 * it will be removed from the free list by getnewvnode, 1863 * but will not have its reference count incremented until 1864 * after calling vgone. If the reference count were 1865 * incremented first, vgone would (incorrectly) try to 1866 * close the previous instance of the underlying object. 1867 */ 1868 if (vp->v_usecount == 0 && !(vp->v_flag & VDOOMED)) { 1869 s = splbio(); 1870 simple_lock(&vnode_free_list_slock); 1871 if (vp->v_flag & VFREE) { 1872 TAILQ_REMOVE(&vnode_free_list, vp, v_freelist); 1873 } else if (vp->v_flag & VTBFREE) { 1874 TAILQ_REMOVE(&vnode_tobefree_list, vp, v_freelist); 1875 vp->v_flag &= ~VTBFREE; 1876 freevnodes++; 1877 } else 1878 freevnodes++; 1879 vp->v_flag |= VFREE; 1880 TAILQ_INSERT_HEAD(&vnode_free_list, vp, v_freelist); 1881 simple_unlock(&vnode_free_list_slock); 1882 splx(s); 1883 } 1884 1885 vp->v_type = VBAD; 1886 simple_unlock(&vp->v_interlock); 1887 } 1888 1889 /* 1890 * Lookup a vnode by device number. 1891 */ 1892 int 1893 vfinddev(dev, type, vpp) 1894 dev_t dev; 1895 enum vtype type; 1896 struct vnode **vpp; 1897 { 1898 struct vnode *vp; 1899 1900 simple_lock(&spechash_slock); 1901 SLIST_FOREACH(vp, &dev->si_hlist, v_specnext) { 1902 if (type == vp->v_type) { 1903 *vpp = vp; 1904 simple_unlock(&spechash_slock); 1905 return (1); 1906 } 1907 } 1908 simple_unlock(&spechash_slock); 1909 return (0); 1910 } 1911 1912 /* 1913 * Calculate the total number of references to a special device. 1914 */ 1915 int 1916 vcount(vp) 1917 struct vnode *vp; 1918 { 1919 struct vnode *vq; 1920 int count; 1921 1922 count = 0; 1923 simple_lock(&spechash_slock); 1924 SLIST_FOREACH(vq, &vp->v_hashchain, v_specnext) 1925 count += vq->v_usecount; 1926 simple_unlock(&spechash_slock); 1927 return (count); 1928 } 1929 1930 /* 1931 * Same as above, but using the dev_t as argument 1932 */ 1933 1934 int 1935 count_dev(dev) 1936 dev_t dev; 1937 { 1938 struct vnode *vp; 1939 1940 vp = SLIST_FIRST(&dev->si_hlist); 1941 if (vp == NULL) 1942 return (0); 1943 return(vcount(vp)); 1944 } 1945 1946 /* 1947 * Print out a description of a vnode. 1948 */ 1949 static char *typename[] = 1950 {"VNON", "VREG", "VDIR", "VBLK", "VCHR", "VLNK", "VSOCK", "VFIFO", "VBAD"}; 1951 1952 void 1953 vprint(label, vp) 1954 char *label; 1955 struct vnode *vp; 1956 { 1957 char buf[96]; 1958 1959 if (label != NULL) 1960 printf("%s: %p: ", label, (void *)vp); 1961 else 1962 printf("%p: ", (void *)vp); 1963 printf("type %s, usecount %d, writecount %d, refcount %d,", 1964 typename[vp->v_type], vp->v_usecount, vp->v_writecount, 1965 vp->v_holdcnt); 1966 buf[0] = '\0'; 1967 if (vp->v_flag & VROOT) 1968 strcat(buf, "|VROOT"); 1969 if (vp->v_flag & VTEXT) 1970 strcat(buf, "|VTEXT"); 1971 if (vp->v_flag & VSYSTEM) 1972 strcat(buf, "|VSYSTEM"); 1973 if (vp->v_flag & VXLOCK) 1974 strcat(buf, "|VXLOCK"); 1975 if (vp->v_flag & VXWANT) 1976 strcat(buf, "|VXWANT"); 1977 if (vp->v_flag & VBWAIT) 1978 strcat(buf, "|VBWAIT"); 1979 if (vp->v_flag & VDOOMED) 1980 strcat(buf, "|VDOOMED"); 1981 if (vp->v_flag & VFREE) 1982 strcat(buf, "|VFREE"); 1983 if (vp->v_flag & VOBJBUF) 1984 strcat(buf, "|VOBJBUF"); 1985 if (buf[0] != '\0') 1986 printf(" flags (%s)", &buf[1]); 1987 if (vp->v_data == NULL) { 1988 printf("\n"); 1989 } else { 1990 printf("\n\t"); 1991 VOP_PRINT(vp); 1992 } 1993 } 1994 1995 #ifdef DDB 1996 #include <ddb/ddb.h> 1997 /* 1998 * List all of the locked vnodes in the system. 1999 * Called when debugging the kernel. 2000 */ 2001 DB_SHOW_COMMAND(lockedvnodes, lockedvnodes) 2002 { 2003 struct proc *p = curproc; /* XXX */ 2004 struct mount *mp, *nmp; 2005 struct vnode *vp; 2006 2007 printf("Locked vnodes\n"); 2008 simple_lock(&mountlist_slock); 2009 for (mp = TAILQ_FIRST(&mountlist); mp != NULL; mp = nmp) { 2010 if (vfs_busy(mp, LK_NOWAIT, &mountlist_slock, p)) { 2011 nmp = TAILQ_NEXT(mp, mnt_list); 2012 continue; 2013 } 2014 LIST_FOREACH(vp, &mp->mnt_vnodelist, v_mntvnodes) { 2015 if (VOP_ISLOCKED(vp, NULL)) 2016 vprint((char *)0, vp); 2017 } 2018 simple_lock(&mountlist_slock); 2019 nmp = TAILQ_NEXT(mp, mnt_list); 2020 vfs_unbusy(mp, p); 2021 } 2022 simple_unlock(&mountlist_slock); 2023 } 2024 #endif 2025 2026 /* 2027 * Top level filesystem related information gathering. 2028 */ 2029 static int sysctl_ovfs_conf __P(SYSCTL_HANDLER_ARGS); 2030 2031 static int 2032 vfs_sysctl SYSCTL_HANDLER_ARGS 2033 { 2034 int *name = (int *)arg1 - 1; /* XXX */ 2035 u_int namelen = arg2 + 1; /* XXX */ 2036 struct vfsconf *vfsp; 2037 2038 #if 1 || defined(COMPAT_PRELITE2) 2039 /* Resolve ambiguity between VFS_VFSCONF and VFS_GENERIC. */ 2040 if (namelen == 1) 2041 return (sysctl_ovfs_conf(oidp, arg1, arg2, req)); 2042 #endif 2043 2044 #ifdef notyet 2045 /* all sysctl names at this level are at least name and field */ 2046 if (namelen < 2) 2047 return (ENOTDIR); /* overloaded */ 2048 if (name[0] != VFS_GENERIC) { 2049 for (vfsp = vfsconf; vfsp; vfsp = vfsp->vfc_next) 2050 if (vfsp->vfc_typenum == name[0]) 2051 break; 2052 if (vfsp == NULL) 2053 return (EOPNOTSUPP); 2054 return ((*vfsp->vfc_vfsops->vfs_sysctl)(&name[1], namelen - 1, 2055 oldp, oldlenp, newp, newlen, p)); 2056 } 2057 #endif 2058 switch (name[1]) { 2059 case VFS_MAXTYPENUM: 2060 if (namelen != 2) 2061 return (ENOTDIR); 2062 return (SYSCTL_OUT(req, &maxvfsconf, sizeof(int))); 2063 case VFS_CONF: 2064 if (namelen != 3) 2065 return (ENOTDIR); /* overloaded */ 2066 for (vfsp = vfsconf; vfsp; vfsp = vfsp->vfc_next) 2067 if (vfsp->vfc_typenum == name[2]) 2068 break; 2069 if (vfsp == NULL) 2070 return (EOPNOTSUPP); 2071 return (SYSCTL_OUT(req, vfsp, sizeof *vfsp)); 2072 } 2073 return (EOPNOTSUPP); 2074 } 2075 2076 SYSCTL_NODE(_vfs, VFS_GENERIC, generic, CTLFLAG_RD, vfs_sysctl, 2077 "Generic filesystem"); 2078 2079 #if 1 || defined(COMPAT_PRELITE2) 2080 2081 static int 2082 sysctl_ovfs_conf SYSCTL_HANDLER_ARGS 2083 { 2084 int error; 2085 struct vfsconf *vfsp; 2086 struct ovfsconf ovfs; 2087 2088 for (vfsp = vfsconf; vfsp; vfsp = vfsp->vfc_next) { 2089 ovfs.vfc_vfsops = vfsp->vfc_vfsops; /* XXX used as flag */ 2090 strcpy(ovfs.vfc_name, vfsp->vfc_name); 2091 ovfs.vfc_index = vfsp->vfc_typenum; 2092 ovfs.vfc_refcount = vfsp->vfc_refcount; 2093 ovfs.vfc_flags = vfsp->vfc_flags; 2094 error = SYSCTL_OUT(req, &ovfs, sizeof ovfs); 2095 if (error) 2096 return error; 2097 } 2098 return 0; 2099 } 2100 2101 #endif /* 1 || COMPAT_PRELITE2 */ 2102 2103 #if 0 2104 #define KINFO_VNODESLOP 10 2105 /* 2106 * Dump vnode list (via sysctl). 2107 * Copyout address of vnode followed by vnode. 2108 */ 2109 /* ARGSUSED */ 2110 static int 2111 sysctl_vnode SYSCTL_HANDLER_ARGS 2112 { 2113 struct proc *p = curproc; /* XXX */ 2114 struct mount *mp, *nmp; 2115 struct vnode *nvp, *vp; 2116 int error; 2117 2118 #define VPTRSZ sizeof (struct vnode *) 2119 #define VNODESZ sizeof (struct vnode) 2120 2121 req->lock = 0; 2122 if (!req->oldptr) /* Make an estimate */ 2123 return (SYSCTL_OUT(req, 0, 2124 (numvnodes + KINFO_VNODESLOP) * (VPTRSZ + VNODESZ))); 2125 2126 simple_lock(&mountlist_slock); 2127 for (mp = TAILQ_FIRST(&mountlist); mp != NULL; mp = nmp) { 2128 if (vfs_busy(mp, LK_NOWAIT, &mountlist_slock, p)) { 2129 nmp = TAILQ_NEXT(mp, mnt_list); 2130 continue; 2131 } 2132 again: 2133 simple_lock(&mntvnode_slock); 2134 for (vp = LIST_FIRST(&mp->mnt_vnodelist); 2135 vp != NULL; 2136 vp = nvp) { 2137 /* 2138 * Check that the vp is still associated with 2139 * this filesystem. RACE: could have been 2140 * recycled onto the same filesystem. 2141 */ 2142 if (vp->v_mount != mp) { 2143 simple_unlock(&mntvnode_slock); 2144 goto again; 2145 } 2146 nvp = LIST_NEXT(vp, v_mntvnodes); 2147 simple_unlock(&mntvnode_slock); 2148 if ((error = SYSCTL_OUT(req, &vp, VPTRSZ)) || 2149 (error = SYSCTL_OUT(req, vp, VNODESZ))) 2150 return (error); 2151 simple_lock(&mntvnode_slock); 2152 } 2153 simple_unlock(&mntvnode_slock); 2154 simple_lock(&mountlist_slock); 2155 nmp = TAILQ_NEXT(mp, mnt_list); 2156 vfs_unbusy(mp, p); 2157 } 2158 simple_unlock(&mountlist_slock); 2159 2160 return (0); 2161 } 2162 #endif 2163 2164 /* 2165 * XXX 2166 * Exporting the vnode list on large systems causes them to crash. 2167 * Exporting the vnode list on medium systems causes sysctl to coredump. 2168 */ 2169 #if 0 2170 SYSCTL_PROC(_kern, KERN_VNODE, vnode, CTLTYPE_OPAQUE|CTLFLAG_RD, 2171 0, 0, sysctl_vnode, "S,vnode", ""); 2172 #endif 2173 2174 /* 2175 * Check to see if a filesystem is mounted on a block device. 2176 */ 2177 int 2178 vfs_mountedon(vp) 2179 struct vnode *vp; 2180 { 2181 2182 if (vp->v_specmountpoint != NULL) 2183 return (EBUSY); 2184 return (0); 2185 } 2186 2187 /* 2188 * Unmount all filesystems. The list is traversed in reverse order 2189 * of mounting to avoid dependencies. 2190 */ 2191 void 2192 vfs_unmountall() 2193 { 2194 struct mount *mp; 2195 struct proc *p; 2196 int error; 2197 2198 if (curproc != NULL) 2199 p = curproc; 2200 else 2201 p = initproc; /* XXX XXX should this be proc0? */ 2202 /* 2203 * Since this only runs when rebooting, it is not interlocked. 2204 */ 2205 while(!TAILQ_EMPTY(&mountlist)) { 2206 mp = TAILQ_LAST(&mountlist, mntlist); 2207 error = dounmount(mp, MNT_FORCE, p); 2208 if (error) { 2209 TAILQ_REMOVE(&mountlist, mp, mnt_list); 2210 printf("unmount of %s failed (", 2211 mp->mnt_stat.f_mntonname); 2212 if (error == EBUSY) 2213 printf("BUSY)\n"); 2214 else 2215 printf("%d)\n", error); 2216 } else { 2217 /* The unmount has removed mp from the mountlist */ 2218 } 2219 } 2220 } 2221 2222 /* 2223 * Build hash lists of net addresses and hang them off the mount point. 2224 * Called by ufs_mount() to set up the lists of export addresses. 2225 */ 2226 static int 2227 vfs_hang_addrlist(mp, nep, argp) 2228 struct mount *mp; 2229 struct netexport *nep; 2230 struct export_args *argp; 2231 { 2232 register struct netcred *np; 2233 register struct radix_node_head *rnh; 2234 register int i; 2235 struct radix_node *rn; 2236 struct sockaddr *saddr, *smask = 0; 2237 struct domain *dom; 2238 int error; 2239 2240 if (argp->ex_addrlen == 0) { 2241 if (mp->mnt_flag & MNT_DEFEXPORTED) 2242 return (EPERM); 2243 np = &nep->ne_defexported; 2244 np->netc_exflags = argp->ex_flags; 2245 np->netc_anon = argp->ex_anon; 2246 np->netc_anon.cr_ref = 1; 2247 mp->mnt_flag |= MNT_DEFEXPORTED; 2248 return (0); 2249 } 2250 i = sizeof(struct netcred) + argp->ex_addrlen + argp->ex_masklen; 2251 np = (struct netcred *) malloc(i, M_NETADDR, M_WAITOK); 2252 bzero((caddr_t) np, i); 2253 saddr = (struct sockaddr *) (np + 1); 2254 if ((error = copyin(argp->ex_addr, (caddr_t) saddr, argp->ex_addrlen))) 2255 goto out; 2256 if (saddr->sa_len > argp->ex_addrlen) 2257 saddr->sa_len = argp->ex_addrlen; 2258 if (argp->ex_masklen) { 2259 smask = (struct sockaddr *) ((caddr_t) saddr + argp->ex_addrlen); 2260 error = copyin(argp->ex_mask, (caddr_t) smask, argp->ex_masklen); 2261 if (error) 2262 goto out; 2263 if (smask->sa_len > argp->ex_masklen) 2264 smask->sa_len = argp->ex_masklen; 2265 } 2266 i = saddr->sa_family; 2267 if ((rnh = nep->ne_rtable[i]) == 0) { 2268 /* 2269 * Seems silly to initialize every AF when most are not used, 2270 * do so on demand here 2271 */ 2272 for (dom = domains; dom; dom = dom->dom_next) 2273 if (dom->dom_family == i && dom->dom_rtattach) { 2274 dom->dom_rtattach((void **) &nep->ne_rtable[i], 2275 dom->dom_rtoffset); 2276 break; 2277 } 2278 if ((rnh = nep->ne_rtable[i]) == 0) { 2279 error = ENOBUFS; 2280 goto out; 2281 } 2282 } 2283 rn = (*rnh->rnh_addaddr) ((caddr_t) saddr, (caddr_t) smask, rnh, 2284 np->netc_rnodes); 2285 if (rn == 0 || np != (struct netcred *) rn) { /* already exists */ 2286 error = EPERM; 2287 goto out; 2288 } 2289 np->netc_exflags = argp->ex_flags; 2290 np->netc_anon = argp->ex_anon; 2291 np->netc_anon.cr_ref = 1; 2292 return (0); 2293 out: 2294 free(np, M_NETADDR); 2295 return (error); 2296 } 2297 2298 /* ARGSUSED */ 2299 static int 2300 vfs_free_netcred(rn, w) 2301 struct radix_node *rn; 2302 void *w; 2303 { 2304 register struct radix_node_head *rnh = (struct radix_node_head *) w; 2305 2306 (*rnh->rnh_deladdr) (rn->rn_key, rn->rn_mask, rnh); 2307 free((caddr_t) rn, M_NETADDR); 2308 return (0); 2309 } 2310 2311 /* 2312 * Free the net address hash lists that are hanging off the mount points. 2313 */ 2314 static void 2315 vfs_free_addrlist(nep) 2316 struct netexport *nep; 2317 { 2318 register int i; 2319 register struct radix_node_head *rnh; 2320 2321 for (i = 0; i <= AF_MAX; i++) 2322 if ((rnh = nep->ne_rtable[i])) { 2323 (*rnh->rnh_walktree) (rnh, vfs_free_netcred, 2324 (caddr_t) rnh); 2325 free((caddr_t) rnh, M_RTABLE); 2326 nep->ne_rtable[i] = 0; 2327 } 2328 } 2329 2330 int 2331 vfs_export(mp, nep, argp) 2332 struct mount *mp; 2333 struct netexport *nep; 2334 struct export_args *argp; 2335 { 2336 int error; 2337 2338 if (argp->ex_flags & MNT_DELEXPORT) { 2339 if (mp->mnt_flag & MNT_EXPUBLIC) { 2340 vfs_setpublicfs(NULL, NULL, NULL); 2341 mp->mnt_flag &= ~MNT_EXPUBLIC; 2342 } 2343 vfs_free_addrlist(nep); 2344 mp->mnt_flag &= ~(MNT_EXPORTED | MNT_DEFEXPORTED); 2345 } 2346 if (argp->ex_flags & MNT_EXPORTED) { 2347 if (argp->ex_flags & MNT_EXPUBLIC) { 2348 if ((error = vfs_setpublicfs(mp, nep, argp)) != 0) 2349 return (error); 2350 mp->mnt_flag |= MNT_EXPUBLIC; 2351 } 2352 if ((error = vfs_hang_addrlist(mp, nep, argp))) 2353 return (error); 2354 mp->mnt_flag |= MNT_EXPORTED; 2355 } 2356 return (0); 2357 } 2358 2359 2360 /* 2361 * Set the publicly exported filesystem (WebNFS). Currently, only 2362 * one public filesystem is possible in the spec (RFC 2054 and 2055) 2363 */ 2364 int 2365 vfs_setpublicfs(mp, nep, argp) 2366 struct mount *mp; 2367 struct netexport *nep; 2368 struct export_args *argp; 2369 { 2370 int error; 2371 struct vnode *rvp; 2372 char *cp; 2373 2374 /* 2375 * mp == NULL -> invalidate the current info, the FS is 2376 * no longer exported. May be called from either vfs_export 2377 * or unmount, so check if it hasn't already been done. 2378 */ 2379 if (mp == NULL) { 2380 if (nfs_pub.np_valid) { 2381 nfs_pub.np_valid = 0; 2382 if (nfs_pub.np_index != NULL) { 2383 FREE(nfs_pub.np_index, M_TEMP); 2384 nfs_pub.np_index = NULL; 2385 } 2386 } 2387 return (0); 2388 } 2389 2390 /* 2391 * Only one allowed at a time. 2392 */ 2393 if (nfs_pub.np_valid != 0 && mp != nfs_pub.np_mount) 2394 return (EBUSY); 2395 2396 /* 2397 * Get real filehandle for root of exported FS. 2398 */ 2399 bzero((caddr_t)&nfs_pub.np_handle, sizeof(nfs_pub.np_handle)); 2400 nfs_pub.np_handle.fh_fsid = mp->mnt_stat.f_fsid; 2401 2402 if ((error = VFS_ROOT(mp, &rvp))) 2403 return (error); 2404 2405 if ((error = VFS_VPTOFH(rvp, &nfs_pub.np_handle.fh_fid))) 2406 return (error); 2407 2408 vput(rvp); 2409 2410 /* 2411 * If an indexfile was specified, pull it in. 2412 */ 2413 if (argp->ex_indexfile != NULL) { 2414 MALLOC(nfs_pub.np_index, char *, MAXNAMLEN + 1, M_TEMP, 2415 M_WAITOK); 2416 error = copyinstr(argp->ex_indexfile, nfs_pub.np_index, 2417 MAXNAMLEN, (size_t *)0); 2418 if (!error) { 2419 /* 2420 * Check for illegal filenames. 2421 */ 2422 for (cp = nfs_pub.np_index; *cp; cp++) { 2423 if (*cp == '/') { 2424 error = EINVAL; 2425 break; 2426 } 2427 } 2428 } 2429 if (error) { 2430 FREE(nfs_pub.np_index, M_TEMP); 2431 return (error); 2432 } 2433 } 2434 2435 nfs_pub.np_mount = mp; 2436 nfs_pub.np_valid = 1; 2437 return (0); 2438 } 2439 2440 struct netcred * 2441 vfs_export_lookup(mp, nep, nam) 2442 register struct mount *mp; 2443 struct netexport *nep; 2444 struct sockaddr *nam; 2445 { 2446 register struct netcred *np; 2447 register struct radix_node_head *rnh; 2448 struct sockaddr *saddr; 2449 2450 np = NULL; 2451 if (mp->mnt_flag & MNT_EXPORTED) { 2452 /* 2453 * Lookup in the export list first. 2454 */ 2455 if (nam != NULL) { 2456 saddr = nam; 2457 rnh = nep->ne_rtable[saddr->sa_family]; 2458 if (rnh != NULL) { 2459 np = (struct netcred *) 2460 (*rnh->rnh_matchaddr)((caddr_t)saddr, 2461 rnh); 2462 if (np && np->netc_rnodes->rn_flags & RNF_ROOT) 2463 np = NULL; 2464 } 2465 } 2466 /* 2467 * If no address match, use the default if it exists. 2468 */ 2469 if (np == NULL && mp->mnt_flag & MNT_DEFEXPORTED) 2470 np = &nep->ne_defexported; 2471 } 2472 return (np); 2473 } 2474 2475 /* 2476 * perform msync on all vnodes under a mount point 2477 * the mount point must be locked. 2478 */ 2479 void 2480 vfs_msync(struct mount *mp, int flags) { 2481 struct vnode *vp, *nvp; 2482 struct vm_object *obj; 2483 int anyio, tries; 2484 2485 tries = 5; 2486 loop: 2487 anyio = 0; 2488 for (vp = LIST_FIRST(&mp->mnt_vnodelist); vp != NULL; vp = nvp) { 2489 2490 nvp = LIST_NEXT(vp, v_mntvnodes); 2491 2492 if (vp->v_mount != mp) { 2493 goto loop; 2494 } 2495 2496 if (vp->v_flag & VXLOCK) /* XXX: what if MNT_WAIT? */ 2497 continue; 2498 2499 if (flags != MNT_WAIT) { 2500 obj = vp->v_object; 2501 if (obj == NULL || (obj->flags & OBJ_MIGHTBEDIRTY) == 0) 2502 continue; 2503 if (VOP_ISLOCKED(vp, NULL)) 2504 continue; 2505 } 2506 2507 simple_lock(&vp->v_interlock); 2508 if (vp->v_object && 2509 (vp->v_object->flags & OBJ_MIGHTBEDIRTY)) { 2510 if (!vget(vp, 2511 LK_INTERLOCK | LK_EXCLUSIVE | LK_RETRY | LK_NOOBJ, curproc)) { 2512 if (vp->v_object) { 2513 vm_object_page_clean(vp->v_object, 0, 0, flags == MNT_WAIT ? OBJPC_SYNC : OBJPC_NOSYNC); 2514 anyio = 1; 2515 } 2516 vput(vp); 2517 } 2518 } else { 2519 simple_unlock(&vp->v_interlock); 2520 } 2521 } 2522 if (anyio && (--tries > 0)) 2523 goto loop; 2524 } 2525 2526 /* 2527 * Create the VM object needed for VMIO and mmap support. This 2528 * is done for all VREG files in the system. Some filesystems might 2529 * afford the additional metadata buffering capability of the 2530 * VMIO code by making the device node be VMIO mode also. 2531 * 2532 * vp must be locked when vfs_object_create is called. 2533 */ 2534 int 2535 vfs_object_create(vp, p, cred) 2536 struct vnode *vp; 2537 struct proc *p; 2538 struct ucred *cred; 2539 { 2540 struct vattr vat; 2541 vm_object_t object; 2542 int error = 0; 2543 2544 if (!vn_isdisk(vp, NULL) && vn_canvmio(vp) == FALSE) 2545 return 0; 2546 2547 retry: 2548 if ((object = vp->v_object) == NULL) { 2549 if (vp->v_type == VREG || vp->v_type == VDIR) { 2550 if ((error = VOP_GETATTR(vp, &vat, cred, p)) != 0) 2551 goto retn; 2552 object = vnode_pager_alloc(vp, vat.va_size, 0, 0); 2553 } else if (devsw(vp->v_rdev) != NULL) { 2554 /* 2555 * This simply allocates the biggest object possible 2556 * for a disk vnode. This should be fixed, but doesn't 2557 * cause any problems (yet). 2558 */ 2559 object = vnode_pager_alloc(vp, IDX_TO_OFF(INT_MAX), 0, 0); 2560 } else { 2561 goto retn; 2562 } 2563 /* 2564 * Dereference the reference we just created. This assumes 2565 * that the object is associated with the vp. 2566 */ 2567 object->ref_count--; 2568 vp->v_usecount--; 2569 } else { 2570 if (object->flags & OBJ_DEAD) { 2571 VOP_UNLOCK(vp, 0, p); 2572 tsleep(object, PVM, "vodead", 0); 2573 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p); 2574 goto retry; 2575 } 2576 } 2577 2578 KASSERT(vp->v_object != NULL, ("vfs_object_create: NULL object")); 2579 vp->v_flag |= VOBJBUF; 2580 2581 retn: 2582 return error; 2583 } 2584 2585 static void 2586 vfree(vp) 2587 struct vnode *vp; 2588 { 2589 int s; 2590 2591 s = splbio(); 2592 simple_lock(&vnode_free_list_slock); 2593 if (vp->v_flag & VTBFREE) { 2594 TAILQ_REMOVE(&vnode_tobefree_list, vp, v_freelist); 2595 vp->v_flag &= ~VTBFREE; 2596 } 2597 if (vp->v_flag & VAGE) { 2598 TAILQ_INSERT_HEAD(&vnode_free_list, vp, v_freelist); 2599 } else { 2600 TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_freelist); 2601 } 2602 freevnodes++; 2603 simple_unlock(&vnode_free_list_slock); 2604 vp->v_flag &= ~VAGE; 2605 vp->v_flag |= VFREE; 2606 splx(s); 2607 } 2608 2609 void 2610 vbusy(vp) 2611 struct vnode *vp; 2612 { 2613 int s; 2614 2615 s = splbio(); 2616 simple_lock(&vnode_free_list_slock); 2617 if (vp->v_flag & VTBFREE) { 2618 TAILQ_REMOVE(&vnode_tobefree_list, vp, v_freelist); 2619 vp->v_flag &= ~VTBFREE; 2620 } else { 2621 TAILQ_REMOVE(&vnode_free_list, vp, v_freelist); 2622 freevnodes--; 2623 } 2624 simple_unlock(&vnode_free_list_slock); 2625 vp->v_flag &= ~(VFREE|VAGE); 2626 splx(s); 2627 } 2628 2629 /* 2630 * Record a process's interest in events which might happen to 2631 * a vnode. Because poll uses the historic select-style interface 2632 * internally, this routine serves as both the ``check for any 2633 * pending events'' and the ``record my interest in future events'' 2634 * functions. (These are done together, while the lock is held, 2635 * to avoid race conditions.) 2636 */ 2637 int 2638 vn_pollrecord(vp, p, events) 2639 struct vnode *vp; 2640 struct proc *p; 2641 short events; 2642 { 2643 simple_lock(&vp->v_pollinfo.vpi_lock); 2644 if (vp->v_pollinfo.vpi_revents & events) { 2645 /* 2646 * This leaves events we are not interested 2647 * in available for the other process which 2648 * which presumably had requested them 2649 * (otherwise they would never have been 2650 * recorded). 2651 */ 2652 events &= vp->v_pollinfo.vpi_revents; 2653 vp->v_pollinfo.vpi_revents &= ~events; 2654 2655 simple_unlock(&vp->v_pollinfo.vpi_lock); 2656 return events; 2657 } 2658 vp->v_pollinfo.vpi_events |= events; 2659 selrecord(p, &vp->v_pollinfo.vpi_selinfo); 2660 simple_unlock(&vp->v_pollinfo.vpi_lock); 2661 return 0; 2662 } 2663 2664 /* 2665 * Note the occurrence of an event. If the VN_POLLEVENT macro is used, 2666 * it is possible for us to miss an event due to race conditions, but 2667 * that condition is expected to be rare, so for the moment it is the 2668 * preferred interface. 2669 */ 2670 void 2671 vn_pollevent(vp, events) 2672 struct vnode *vp; 2673 short events; 2674 { 2675 simple_lock(&vp->v_pollinfo.vpi_lock); 2676 if (vp->v_pollinfo.vpi_events & events) { 2677 /* 2678 * We clear vpi_events so that we don't 2679 * call selwakeup() twice if two events are 2680 * posted before the polling process(es) is 2681 * awakened. This also ensures that we take at 2682 * most one selwakeup() if the polling process 2683 * is no longer interested. However, it does 2684 * mean that only one event can be noticed at 2685 * a time. (Perhaps we should only clear those 2686 * event bits which we note?) XXX 2687 */ 2688 vp->v_pollinfo.vpi_events = 0; /* &= ~events ??? */ 2689 vp->v_pollinfo.vpi_revents |= events; 2690 selwakeup(&vp->v_pollinfo.vpi_selinfo); 2691 } 2692 simple_unlock(&vp->v_pollinfo.vpi_lock); 2693 } 2694 2695 /* 2696 * Wake up anyone polling on vp because it is being revoked. 2697 * This depends on dead_poll() returning POLLHUP for correct 2698 * behavior. 2699 */ 2700 void 2701 vn_pollgone(vp) 2702 struct vnode *vp; 2703 { 2704 simple_lock(&vp->v_pollinfo.vpi_lock); 2705 if (vp->v_pollinfo.vpi_events) { 2706 vp->v_pollinfo.vpi_events = 0; 2707 selwakeup(&vp->v_pollinfo.vpi_selinfo); 2708 } 2709 simple_unlock(&vp->v_pollinfo.vpi_lock); 2710 } 2711 2712 2713 2714 /* 2715 * Routine to create and manage a filesystem syncer vnode. 2716 */ 2717 #define sync_close ((int (*) __P((struct vop_close_args *)))nullop) 2718 static int sync_fsync __P((struct vop_fsync_args *)); 2719 static int sync_inactive __P((struct vop_inactive_args *)); 2720 static int sync_reclaim __P((struct vop_reclaim_args *)); 2721 #define sync_lock ((int (*) __P((struct vop_lock_args *)))vop_nolock) 2722 #define sync_unlock ((int (*) __P((struct vop_unlock_args *)))vop_nounlock) 2723 static int sync_print __P((struct vop_print_args *)); 2724 #define sync_islocked ((int(*) __P((struct vop_islocked_args *)))vop_noislocked) 2725 2726 static vop_t **sync_vnodeop_p; 2727 static struct vnodeopv_entry_desc sync_vnodeop_entries[] = { 2728 { &vop_default_desc, (vop_t *) vop_eopnotsupp }, 2729 { &vop_close_desc, (vop_t *) sync_close }, /* close */ 2730 { &vop_fsync_desc, (vop_t *) sync_fsync }, /* fsync */ 2731 { &vop_inactive_desc, (vop_t *) sync_inactive }, /* inactive */ 2732 { &vop_reclaim_desc, (vop_t *) sync_reclaim }, /* reclaim */ 2733 { &vop_lock_desc, (vop_t *) sync_lock }, /* lock */ 2734 { &vop_unlock_desc, (vop_t *) sync_unlock }, /* unlock */ 2735 { &vop_print_desc, (vop_t *) sync_print }, /* print */ 2736 { &vop_islocked_desc, (vop_t *) sync_islocked }, /* islocked */ 2737 { NULL, NULL } 2738 }; 2739 static struct vnodeopv_desc sync_vnodeop_opv_desc = 2740 { &sync_vnodeop_p, sync_vnodeop_entries }; 2741 2742 VNODEOP_SET(sync_vnodeop_opv_desc); 2743 2744 /* 2745 * Create a new filesystem syncer vnode for the specified mount point. 2746 */ 2747 int 2748 vfs_allocate_syncvnode(mp) 2749 struct mount *mp; 2750 { 2751 struct vnode *vp; 2752 static long start, incr, next; 2753 int error; 2754 2755 /* Allocate a new vnode */ 2756 if ((error = getnewvnode(VT_VFS, mp, sync_vnodeop_p, &vp)) != 0) { 2757 mp->mnt_syncer = NULL; 2758 return (error); 2759 } 2760 vp->v_type = VNON; 2761 /* 2762 * Place the vnode onto the syncer worklist. We attempt to 2763 * scatter them about on the list so that they will go off 2764 * at evenly distributed times even if all the filesystems 2765 * are mounted at once. 2766 */ 2767 next += incr; 2768 if (next == 0 || next > syncer_maxdelay) { 2769 start /= 2; 2770 incr /= 2; 2771 if (start == 0) { 2772 start = syncer_maxdelay / 2; 2773 incr = syncer_maxdelay; 2774 } 2775 next = start; 2776 } 2777 vn_syncer_add_to_worklist(vp, syncdelay > 0 ? next % syncdelay : 0); 2778 mp->mnt_syncer = vp; 2779 return (0); 2780 } 2781 2782 /* 2783 * Do a lazy sync of the filesystem. 2784 */ 2785 static int 2786 sync_fsync(ap) 2787 struct vop_fsync_args /* { 2788 struct vnode *a_vp; 2789 struct ucred *a_cred; 2790 int a_waitfor; 2791 struct proc *a_p; 2792 } */ *ap; 2793 { 2794 struct vnode *syncvp = ap->a_vp; 2795 struct mount *mp = syncvp->v_mount; 2796 struct proc *p = ap->a_p; 2797 int asyncflag; 2798 2799 /* 2800 * We only need to do something if this is a lazy evaluation. 2801 */ 2802 if (ap->a_waitfor != MNT_LAZY) 2803 return (0); 2804 2805 /* 2806 * Move ourselves to the back of the sync list. 2807 */ 2808 vn_syncer_add_to_worklist(syncvp, syncdelay); 2809 2810 /* 2811 * Walk the list of vnodes pushing all that are dirty and 2812 * not already on the sync list. 2813 */ 2814 simple_lock(&mountlist_slock); 2815 if (vfs_busy(mp, LK_EXCLUSIVE | LK_NOWAIT, &mountlist_slock, p) != 0) { 2816 simple_unlock(&mountlist_slock); 2817 return (0); 2818 } 2819 asyncflag = mp->mnt_flag & MNT_ASYNC; 2820 mp->mnt_flag &= ~MNT_ASYNC; 2821 vfs_msync(mp, MNT_NOWAIT); 2822 VFS_SYNC(mp, MNT_LAZY, ap->a_cred, p); 2823 if (asyncflag) 2824 mp->mnt_flag |= MNT_ASYNC; 2825 vfs_unbusy(mp, p); 2826 return (0); 2827 } 2828 2829 /* 2830 * The syncer vnode is no referenced. 2831 */ 2832 static int 2833 sync_inactive(ap) 2834 struct vop_inactive_args /* { 2835 struct vnode *a_vp; 2836 struct proc *a_p; 2837 } */ *ap; 2838 { 2839 2840 vgone(ap->a_vp); 2841 return (0); 2842 } 2843 2844 /* 2845 * The syncer vnode is no longer needed and is being decommissioned. 2846 * 2847 * Modifications to the worklist must be protected at splbio(). 2848 */ 2849 static int 2850 sync_reclaim(ap) 2851 struct vop_reclaim_args /* { 2852 struct vnode *a_vp; 2853 } */ *ap; 2854 { 2855 struct vnode *vp = ap->a_vp; 2856 int s; 2857 2858 s = splbio(); 2859 vp->v_mount->mnt_syncer = NULL; 2860 if (vp->v_flag & VONWORKLST) { 2861 LIST_REMOVE(vp, v_synclist); 2862 vp->v_flag &= ~VONWORKLST; 2863 } 2864 splx(s); 2865 2866 return (0); 2867 } 2868 2869 /* 2870 * Print out a syncer vnode. 2871 */ 2872 static int 2873 sync_print(ap) 2874 struct vop_print_args /* { 2875 struct vnode *a_vp; 2876 } */ *ap; 2877 { 2878 struct vnode *vp = ap->a_vp; 2879 2880 printf("syncer vnode"); 2881 if (vp->v_vnlock != NULL) 2882 lockmgr_printinfo(vp->v_vnlock); 2883 printf("\n"); 2884 return (0); 2885 } 2886 2887 /* 2888 * extract the dev_t from a VBLK or VCHR 2889 */ 2890 dev_t 2891 vn_todev(vp) 2892 struct vnode *vp; 2893 { 2894 if (vp->v_type != VBLK && vp->v_type != VCHR) 2895 return (NODEV); 2896 return (vp->v_rdev); 2897 } 2898 2899 /* 2900 * Check if vnode represents a disk device 2901 */ 2902 int 2903 vn_isdisk(vp, errp) 2904 struct vnode *vp; 2905 int *errp; 2906 { 2907 if (vp->v_type != VBLK && vp->v_type != VCHR) { 2908 if (errp != NULL) 2909 *errp = ENOTBLK; 2910 return (0); 2911 } 2912 if (vp->v_rdev == NULL) { 2913 if (errp != NULL) 2914 *errp = ENXIO; 2915 return (0); 2916 } 2917 if (!devsw(vp->v_rdev)) { 2918 if (errp != NULL) 2919 *errp = ENXIO; 2920 return (0); 2921 } 2922 if (!(devsw(vp->v_rdev)->d_flags & D_DISK)) { 2923 if (errp != NULL) 2924 *errp = ENOTBLK; 2925 return (0); 2926 } 2927 if (errp != NULL) 2928 *errp = 0; 2929 return (1); 2930 } 2931 2932 void 2933 NDFREE(ndp, flags) 2934 struct nameidata *ndp; 2935 const uint flags; 2936 { 2937 if (!(flags & NDF_NO_FREE_PNBUF) && 2938 (ndp->ni_cnd.cn_flags & HASBUF)) { 2939 zfree(namei_zone, ndp->ni_cnd.cn_pnbuf); 2940 ndp->ni_cnd.cn_flags &= ~HASBUF; 2941 } 2942 if (!(flags & NDF_NO_DVP_UNLOCK) && 2943 (ndp->ni_cnd.cn_flags & LOCKPARENT) && 2944 ndp->ni_dvp != ndp->ni_vp) 2945 VOP_UNLOCK(ndp->ni_dvp, 0, ndp->ni_cnd.cn_proc); 2946 if (!(flags & NDF_NO_DVP_RELE) && 2947 (ndp->ni_cnd.cn_flags & (LOCKPARENT|WANTPARENT))) { 2948 vrele(ndp->ni_dvp); 2949 ndp->ni_dvp = NULL; 2950 } 2951 if (!(flags & NDF_NO_VP_UNLOCK) && 2952 (ndp->ni_cnd.cn_flags & LOCKLEAF) && ndp->ni_vp) 2953 VOP_UNLOCK(ndp->ni_vp, 0, ndp->ni_cnd.cn_proc); 2954 if (!(flags & NDF_NO_VP_RELE) && 2955 ndp->ni_vp) { 2956 vrele(ndp->ni_vp); 2957 ndp->ni_vp = NULL; 2958 } 2959 if (!(flags & NDF_NO_STARTDIR_RELE) && 2960 (ndp->ni_cnd.cn_flags & SAVESTART)) { 2961 vrele(ndp->ni_startdir); 2962 ndp->ni_startdir = NULL; 2963 } 2964 } 2965