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 #include "opt_ffs.h" 47 48 #include <sys/param.h> 49 #include <sys/systm.h> 50 #include <sys/bio.h> 51 #include <sys/buf.h> 52 #include <sys/conf.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/stat.h> 61 #include <sys/sysctl.h> 62 #include <sys/vmmeter.h> 63 #include <sys/vnode.h> 64 65 #include <vm/vm.h> 66 #include <vm/vm_object.h> 67 #include <vm/vm_extern.h> 68 #include <vm/pmap.h> 69 #include <vm/vm_map.h> 70 #include <vm/vm_page.h> 71 #include <vm/vm_zone.h> 72 73 static MALLOC_DEFINE(M_NETADDR, "Export Host", "Export host address structure"); 74 75 static void addalias __P((struct vnode *vp, dev_t nvp_rdev)); 76 static void insmntque __P((struct vnode *vp, struct mount *mp)); 77 static void vclean __P((struct vnode *vp, int flags, struct proc *p)); 78 79 /* 80 * Number of vnodes in existence. Increased whenever getnewvnode() 81 * allocates a new vnode, never decreased. 82 */ 83 static unsigned long numvnodes; 84 SYSCTL_LONG(_debug, OID_AUTO, numvnodes, CTLFLAG_RD, &numvnodes, 0, ""); 85 86 /* 87 * Conversion tables for conversion from vnode types to inode formats 88 * and back. 89 */ 90 enum vtype iftovt_tab[16] = { 91 VNON, VFIFO, VCHR, VNON, VDIR, VNON, VBLK, VNON, 92 VREG, VNON, VLNK, VNON, VSOCK, VNON, VNON, VBAD, 93 }; 94 int vttoif_tab[9] = { 95 0, S_IFREG, S_IFDIR, S_IFBLK, S_IFCHR, S_IFLNK, 96 S_IFSOCK, S_IFIFO, S_IFMT, 97 }; 98 99 /* 100 * List of vnodes that are ready for recycling. 101 */ 102 static TAILQ_HEAD(freelst, vnode) vnode_free_list; 103 104 /* 105 * Minimum number of free vnodes. If there are fewer than this free vnodes, 106 * getnewvnode() will return a newly allocated vnode. 107 */ 108 static u_long wantfreevnodes = 25; 109 SYSCTL_LONG(_debug, OID_AUTO, wantfreevnodes, CTLFLAG_RW, &wantfreevnodes, 0, ""); 110 /* Number of vnodes in the free list. */ 111 static u_long freevnodes = 0; 112 SYSCTL_LONG(_debug, OID_AUTO, freevnodes, CTLFLAG_RD, &freevnodes, 0, ""); 113 /* Number of vnode allocation. */ 114 static u_long vnodeallocs = 0; 115 SYSCTL_LONG(_debug, OID_AUTO, vnodeallocs, CTLFLAG_RD, &vnodeallocs, 0, ""); 116 /* Period of vnode recycle from namecache in vnode allocation times. */ 117 static u_long vnoderecycleperiod = 1000; 118 SYSCTL_LONG(_debug, OID_AUTO, vnoderecycleperiod, CTLFLAG_RW, &vnoderecycleperiod, 0, ""); 119 /* Minimum number of total vnodes required to invoke vnode recycle from namecache. */ 120 static u_long vnoderecyclemintotalvn = 2000; 121 SYSCTL_LONG(_debug, OID_AUTO, vnoderecyclemintotalvn, CTLFLAG_RW, &vnoderecyclemintotalvn, 0, ""); 122 /* Minimum number of free vnodes required to invoke vnode recycle from namecache. */ 123 static u_long vnoderecycleminfreevn = 2000; 124 SYSCTL_LONG(_debug, OID_AUTO, vnoderecycleminfreevn, CTLFLAG_RW, &vnoderecycleminfreevn, 0, ""); 125 /* Number of vnodes attempted to recycle at a time. */ 126 static u_long vnoderecyclenumber = 3000; 127 SYSCTL_LONG(_debug, OID_AUTO, vnoderecyclenumber, CTLFLAG_RW, &vnoderecyclenumber, 0, ""); 128 129 /* 130 * Various variables used for debugging the new implementation of 131 * reassignbuf(). 132 * XXX these are probably of (very) limited utility now. 133 */ 134 static int reassignbufcalls; 135 SYSCTL_INT(_vfs, OID_AUTO, reassignbufcalls, CTLFLAG_RW, &reassignbufcalls, 0, ""); 136 static int reassignbufloops; 137 SYSCTL_INT(_vfs, OID_AUTO, reassignbufloops, CTLFLAG_RW, &reassignbufloops, 0, ""); 138 static int reassignbufsortgood; 139 SYSCTL_INT(_vfs, OID_AUTO, reassignbufsortgood, CTLFLAG_RW, &reassignbufsortgood, 0, ""); 140 static int reassignbufsortbad; 141 SYSCTL_INT(_vfs, OID_AUTO, reassignbufsortbad, CTLFLAG_RW, &reassignbufsortbad, 0, ""); 142 /* Set to 0 for old insertion-sort based reassignbuf, 1 for modern method. */ 143 static int reassignbufmethod = 1; 144 SYSCTL_INT(_vfs, OID_AUTO, reassignbufmethod, CTLFLAG_RW, &reassignbufmethod, 0, ""); 145 146 #ifdef ENABLE_VFS_IOOPT 147 /* See NOTES for a description of this setting. */ 148 int vfs_ioopt = 0; 149 SYSCTL_INT(_vfs, OID_AUTO, ioopt, CTLFLAG_RW, &vfs_ioopt, 0, ""); 150 #endif 151 152 /* List of mounted filesystems. */ 153 struct mntlist mountlist = TAILQ_HEAD_INITIALIZER(mountlist); 154 155 /* For any iteration/modification of mountlist */ 156 struct mtx mountlist_mtx; 157 158 /* For any iteration/modification of mnt_vnodelist */ 159 struct mtx mntvnode_mtx; 160 161 /* 162 * Cache for the mount type id assigned to NFS. This is used for 163 * special checks in nfs/nfs_nqlease.c and vm/vnode_pager.c. 164 */ 165 int nfs_mount_type = -1; 166 167 /* To keep more than one thread at a time from running vfs_getnewfsid */ 168 static struct mtx mntid_mtx; 169 170 /* For any iteration/modification of vnode_free_list */ 171 static struct mtx vnode_free_list_mtx; 172 173 /* 174 * For any iteration/modification of dev->si_hlist (linked through 175 * v_specnext) 176 */ 177 static struct mtx spechash_mtx; 178 179 /* Publicly exported FS */ 180 struct nfs_public nfs_pub; 181 182 /* Zone for allocation of new vnodes - used exclusively by getnewvnode() */ 183 static vm_zone_t vnode_zone; 184 185 /* Set to 1 to print out reclaim of active vnodes */ 186 int prtactive = 0; 187 188 /* 189 * The workitem queue. 190 * 191 * It is useful to delay writes of file data and filesystem metadata 192 * for tens of seconds so that quickly created and deleted files need 193 * not waste disk bandwidth being created and removed. To realize this, 194 * we append vnodes to a "workitem" queue. When running with a soft 195 * updates implementation, most pending metadata dependencies should 196 * not wait for more than a few seconds. Thus, mounted on block devices 197 * are delayed only about a half the time that file data is delayed. 198 * Similarly, directory updates are more critical, so are only delayed 199 * about a third the time that file data is delayed. Thus, there are 200 * SYNCER_MAXDELAY queues that are processed round-robin at a rate of 201 * one each second (driven off the filesystem syncer process). The 202 * syncer_delayno variable indicates the next queue that is to be processed. 203 * Items that need to be processed soon are placed in this queue: 204 * 205 * syncer_workitem_pending[syncer_delayno] 206 * 207 * A delay of fifteen seconds is done by placing the request fifteen 208 * entries later in the queue: 209 * 210 * syncer_workitem_pending[(syncer_delayno + 15) & syncer_mask] 211 * 212 */ 213 static int syncer_delayno = 0; 214 static long syncer_mask; 215 LIST_HEAD(synclist, vnode); 216 static struct synclist *syncer_workitem_pending; 217 218 #define SYNCER_MAXDELAY 32 219 static int syncer_maxdelay = SYNCER_MAXDELAY; /* maximum delay time */ 220 time_t syncdelay = 30; /* max time to delay syncing data */ 221 time_t filedelay = 30; /* time to delay syncing files */ 222 SYSCTL_INT(_kern, OID_AUTO, filedelay, CTLFLAG_RW, &filedelay, 0, ""); 223 time_t dirdelay = 29; /* time to delay syncing directories */ 224 SYSCTL_INT(_kern, OID_AUTO, dirdelay, CTLFLAG_RW, &dirdelay, 0, ""); 225 time_t metadelay = 28; /* time to delay syncing metadata */ 226 SYSCTL_INT(_kern, OID_AUTO, metadelay, CTLFLAG_RW, &metadelay, 0, ""); 227 static int rushjob; /* number of slots to run ASAP */ 228 static int stat_rush_requests; /* number of times I/O speeded up */ 229 SYSCTL_INT(_debug, OID_AUTO, rush_requests, CTLFLAG_RW, &stat_rush_requests, 0, ""); 230 231 /* 232 * Number of vnodes we want to exist at any one time. This is mostly used 233 * to size hash tables in vnode-related code. It is normally not used in 234 * getnewvnode(), as wantfreevnodes is normally nonzero.) 235 * 236 * XXX desiredvnodes is historical cruft and should not exist. 237 */ 238 int desiredvnodes; 239 SYSCTL_INT(_kern, KERN_MAXVNODES, maxvnodes, CTLFLAG_RW, 240 &desiredvnodes, 0, "Maximum number of vnodes"); 241 242 /* 243 * Initialize the vnode management data structures. 244 */ 245 static void 246 vntblinit(void *dummy __unused) 247 { 248 249 desiredvnodes = maxproc + cnt.v_page_count / 4; 250 mtx_init(&mountlist_mtx, "mountlist", MTX_DEF); 251 mtx_init(&mntvnode_mtx, "mntvnode", MTX_DEF); 252 mtx_init(&mntid_mtx, "mntid", MTX_DEF); 253 mtx_init(&spechash_mtx, "spechash", MTX_DEF); 254 TAILQ_INIT(&vnode_free_list); 255 mtx_init(&vnode_free_list_mtx, "vnode_free_list", MTX_DEF); 256 vnode_zone = zinit("VNODE", sizeof (struct vnode), 0, 0, 5); 257 /* 258 * Initialize the filesystem syncer. 259 */ 260 syncer_workitem_pending = hashinit(syncer_maxdelay, M_VNODE, 261 &syncer_mask); 262 syncer_maxdelay = syncer_mask + 1; 263 } 264 SYSINIT(vfs, SI_SUB_VFS, SI_ORDER_FIRST, vntblinit, NULL) 265 266 267 /* 268 * Mark a mount point as busy. Used to synchronize access and to delay 269 * unmounting. Interlock is not released on failure. 270 */ 271 int 272 vfs_busy(mp, flags, interlkp, p) 273 struct mount *mp; 274 int flags; 275 struct mtx *interlkp; 276 struct proc *p; 277 { 278 int lkflags; 279 280 if (mp->mnt_kern_flag & MNTK_UNMOUNT) { 281 if (flags & LK_NOWAIT) 282 return (ENOENT); 283 mp->mnt_kern_flag |= MNTK_MWAIT; 284 /* 285 * Since all busy locks are shared except the exclusive 286 * lock granted when unmounting, the only place that a 287 * wakeup needs to be done is at the release of the 288 * exclusive lock at the end of dounmount. 289 */ 290 msleep((caddr_t)mp, interlkp, PVFS, "vfs_busy", 0); 291 return (ENOENT); 292 } 293 lkflags = LK_SHARED | LK_NOPAUSE; 294 if (interlkp) 295 lkflags |= LK_INTERLOCK; 296 if (lockmgr(&mp->mnt_lock, lkflags, interlkp, p)) 297 panic("vfs_busy: unexpected lock failure"); 298 return (0); 299 } 300 301 /* 302 * Free a busy filesystem. 303 */ 304 void 305 vfs_unbusy(mp, p) 306 struct mount *mp; 307 struct proc *p; 308 { 309 310 lockmgr(&mp->mnt_lock, LK_RELEASE, NULL, p); 311 } 312 313 /* 314 * Lookup a filesystem type, and if found allocate and initialize 315 * a mount structure for it. 316 * 317 * Devname is usually updated by mount(8) after booting. 318 */ 319 int 320 vfs_rootmountalloc(fstypename, devname, mpp) 321 char *fstypename; 322 char *devname; 323 struct mount **mpp; 324 { 325 struct proc *p = curproc; /* XXX */ 326 struct vfsconf *vfsp; 327 struct mount *mp; 328 329 if (fstypename == NULL) 330 return (ENODEV); 331 for (vfsp = vfsconf; vfsp; vfsp = vfsp->vfc_next) 332 if (!strcmp(vfsp->vfc_name, fstypename)) 333 break; 334 if (vfsp == NULL) 335 return (ENODEV); 336 mp = malloc((u_long)sizeof(struct mount), M_MOUNT, M_WAITOK | M_ZERO); 337 lockinit(&mp->mnt_lock, PVFS, "vfslock", 0, LK_NOPAUSE); 338 (void)vfs_busy(mp, LK_NOWAIT, 0, p); 339 LIST_INIT(&mp->mnt_vnodelist); 340 mp->mnt_vfc = vfsp; 341 mp->mnt_op = vfsp->vfc_vfsops; 342 mp->mnt_flag = MNT_RDONLY; 343 mp->mnt_vnodecovered = NULLVP; 344 vfsp->vfc_refcount++; 345 mp->mnt_iosize_max = DFLTPHYS; 346 mp->mnt_stat.f_type = vfsp->vfc_typenum; 347 mp->mnt_flag |= vfsp->vfc_flags & MNT_VISFLAGMASK; 348 strncpy(mp->mnt_stat.f_fstypename, vfsp->vfc_name, MFSNAMELEN); 349 mp->mnt_stat.f_mntonname[0] = '/'; 350 mp->mnt_stat.f_mntonname[1] = 0; 351 (void) copystr(devname, mp->mnt_stat.f_mntfromname, MNAMELEN - 1, 0); 352 *mpp = mp; 353 return (0); 354 } 355 356 /* 357 * Find an appropriate filesystem to use for the root. If a filesystem 358 * has not been preselected, walk through the list of known filesystems 359 * trying those that have mountroot routines, and try them until one 360 * works or we have tried them all. 361 */ 362 #ifdef notdef /* XXX JH */ 363 int 364 lite2_vfs_mountroot() 365 { 366 struct vfsconf *vfsp; 367 extern int (*lite2_mountroot) __P((void)); 368 int error; 369 370 if (lite2_mountroot != NULL) 371 return ((*lite2_mountroot)()); 372 for (vfsp = vfsconf; vfsp; vfsp = vfsp->vfc_next) { 373 if (vfsp->vfc_mountroot == NULL) 374 continue; 375 if ((error = (*vfsp->vfc_mountroot)()) == 0) 376 return (0); 377 printf("%s_mountroot failed: %d\n", vfsp->vfc_name, error); 378 } 379 return (ENODEV); 380 } 381 #endif 382 383 /* 384 * Lookup a mount point by filesystem identifier. 385 */ 386 struct mount * 387 vfs_getvfs(fsid) 388 fsid_t *fsid; 389 { 390 register struct mount *mp; 391 392 mtx_lock(&mountlist_mtx); 393 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 394 if (mp->mnt_stat.f_fsid.val[0] == fsid->val[0] && 395 mp->mnt_stat.f_fsid.val[1] == fsid->val[1]) { 396 mtx_unlock(&mountlist_mtx); 397 return (mp); 398 } 399 } 400 mtx_unlock(&mountlist_mtx); 401 return ((struct mount *) 0); 402 } 403 404 /* 405 * Get a new unique fsid. Try to make its val[0] unique, since this value 406 * will be used to create fake device numbers for stat(). Also try (but 407 * not so hard) make its val[0] unique mod 2^16, since some emulators only 408 * support 16-bit device numbers. We end up with unique val[0]'s for the 409 * first 2^16 calls and unique val[0]'s mod 2^16 for the first 2^8 calls. 410 * 411 * Keep in mind that several mounts may be running in parallel. Starting 412 * the search one past where the previous search terminated is both a 413 * micro-optimization and a defense against returning the same fsid to 414 * different mounts. 415 */ 416 void 417 vfs_getnewfsid(mp) 418 struct mount *mp; 419 { 420 static u_int16_t mntid_base; 421 fsid_t tfsid; 422 int mtype; 423 424 mtx_lock(&mntid_mtx); 425 mtype = mp->mnt_vfc->vfc_typenum; 426 tfsid.val[1] = mtype; 427 mtype = (mtype & 0xFF) << 24; 428 for (;;) { 429 tfsid.val[0] = makeudev(255, 430 mtype | ((mntid_base & 0xFF00) << 8) | (mntid_base & 0xFF)); 431 mntid_base++; 432 if (vfs_getvfs(&tfsid) == NULL) 433 break; 434 } 435 mp->mnt_stat.f_fsid.val[0] = tfsid.val[0]; 436 mp->mnt_stat.f_fsid.val[1] = tfsid.val[1]; 437 mtx_unlock(&mntid_mtx); 438 } 439 440 /* 441 * Knob to control the precision of file timestamps: 442 * 443 * 0 = seconds only; nanoseconds zeroed. 444 * 1 = seconds and nanoseconds, accurate within 1/HZ. 445 * 2 = seconds and nanoseconds, truncated to microseconds. 446 * >=3 = seconds and nanoseconds, maximum precision. 447 */ 448 enum { TSP_SEC, TSP_HZ, TSP_USEC, TSP_NSEC }; 449 450 static int timestamp_precision = TSP_SEC; 451 SYSCTL_INT(_vfs, OID_AUTO, timestamp_precision, CTLFLAG_RW, 452 ×tamp_precision, 0, ""); 453 454 /* 455 * Get a current timestamp. 456 */ 457 void 458 vfs_timestamp(tsp) 459 struct timespec *tsp; 460 { 461 struct timeval tv; 462 463 switch (timestamp_precision) { 464 case TSP_SEC: 465 tsp->tv_sec = time_second; 466 tsp->tv_nsec = 0; 467 break; 468 case TSP_HZ: 469 getnanotime(tsp); 470 break; 471 case TSP_USEC: 472 microtime(&tv); 473 TIMEVAL_TO_TIMESPEC(&tv, tsp); 474 break; 475 case TSP_NSEC: 476 default: 477 nanotime(tsp); 478 break; 479 } 480 } 481 482 /* 483 * Set vnode attributes to VNOVAL 484 */ 485 void 486 vattr_null(vap) 487 register struct vattr *vap; 488 { 489 490 vap->va_type = VNON; 491 vap->va_size = VNOVAL; 492 vap->va_bytes = VNOVAL; 493 vap->va_mode = VNOVAL; 494 vap->va_nlink = VNOVAL; 495 vap->va_uid = VNOVAL; 496 vap->va_gid = VNOVAL; 497 vap->va_fsid = VNOVAL; 498 vap->va_fileid = VNOVAL; 499 vap->va_blocksize = VNOVAL; 500 vap->va_rdev = VNOVAL; 501 vap->va_atime.tv_sec = VNOVAL; 502 vap->va_atime.tv_nsec = VNOVAL; 503 vap->va_mtime.tv_sec = VNOVAL; 504 vap->va_mtime.tv_nsec = VNOVAL; 505 vap->va_ctime.tv_sec = VNOVAL; 506 vap->va_ctime.tv_nsec = VNOVAL; 507 vap->va_flags = VNOVAL; 508 vap->va_gen = VNOVAL; 509 vap->va_vaflags = 0; 510 } 511 512 /* 513 * Routines having to do with the management of the vnode table. 514 */ 515 516 /* 517 * Return the next vnode from the free list. 518 */ 519 int 520 getnewvnode(tag, mp, vops, vpp) 521 enum vtagtype tag; 522 struct mount *mp; 523 vop_t **vops; 524 struct vnode **vpp; 525 { 526 int s, count; 527 struct proc *p = curproc; /* XXX */ 528 struct vnode *vp = NULL; 529 struct mount *vnmp; 530 vm_object_t object; 531 532 /* 533 * We take the least recently used vnode from the freelist 534 * if we can get it and it has no cached pages, and no 535 * namecache entries are relative to it. 536 * Otherwise we allocate a new vnode 537 */ 538 539 s = splbio(); 540 mtx_lock(&vnode_free_list_mtx); 541 542 if (wantfreevnodes && freevnodes < wantfreevnodes) { 543 vp = NULL; 544 } else if (!wantfreevnodes && freevnodes <= desiredvnodes) { 545 /* 546 * XXX: this is only here to be backwards compatible 547 */ 548 vp = NULL; 549 } else for (count = 0; count < freevnodes; count++) { 550 vp = TAILQ_FIRST(&vnode_free_list); 551 if (vp == NULL || vp->v_usecount) 552 panic("getnewvnode: free vnode isn't"); 553 TAILQ_REMOVE(&vnode_free_list, vp, v_freelist); 554 555 /* 556 * Don't recycle if active in the namecache or 557 * if it still has cached pages or we cannot get 558 * its interlock. 559 */ 560 if (LIST_FIRST(&vp->v_cache_src) != NULL || 561 (VOP_GETVOBJECT(vp, &object) == 0 && 562 (object->resident_page_count || object->ref_count)) || 563 !mtx_trylock(&vp->v_interlock)) { 564 TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_freelist); 565 vp = NULL; 566 continue; 567 } 568 /* 569 * Skip over it if its filesystem is being suspended. 570 */ 571 if (vn_start_write(vp, &vnmp, V_NOWAIT) == 0) 572 break; 573 mtx_unlock(&vp->v_interlock); 574 TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_freelist); 575 vp = NULL; 576 } 577 if (vp) { 578 vp->v_flag |= VDOOMED; 579 vp->v_flag &= ~VFREE; 580 freevnodes--; 581 mtx_unlock(&vnode_free_list_mtx); 582 cache_purge(vp); 583 vp->v_lease = NULL; 584 if (vp->v_type != VBAD) { 585 vgonel(vp, p); 586 } else { 587 mtx_unlock(&vp->v_interlock); 588 } 589 vn_finished_write(vnmp); 590 591 #ifdef INVARIANTS 592 { 593 int s; 594 595 if (vp->v_data) 596 panic("cleaned vnode isn't"); 597 s = splbio(); 598 if (vp->v_numoutput) 599 panic("Clean vnode has pending I/O's"); 600 splx(s); 601 if (vp->v_writecount != 0) 602 panic("Non-zero write count"); 603 } 604 #endif 605 vp->v_flag = 0; 606 vp->v_lastw = 0; 607 vp->v_lasta = 0; 608 vp->v_cstart = 0; 609 vp->v_clen = 0; 610 vp->v_socket = 0; 611 } else { 612 mtx_unlock(&vnode_free_list_mtx); 613 vp = (struct vnode *) zalloc(vnode_zone); 614 bzero((char *) vp, sizeof *vp); 615 mtx_init(&vp->v_interlock, "vnode interlock", MTX_DEF); 616 vp->v_dd = vp; 617 mtx_init(&vp->v_pollinfo.vpi_lock, "vnode pollinfo", MTX_DEF); 618 cache_purge(vp); 619 LIST_INIT(&vp->v_cache_src); 620 TAILQ_INIT(&vp->v_cache_dst); 621 numvnodes++; 622 } 623 624 TAILQ_INIT(&vp->v_cleanblkhd); 625 TAILQ_INIT(&vp->v_dirtyblkhd); 626 vp->v_type = VNON; 627 vp->v_tag = tag; 628 vp->v_op = vops; 629 lockinit(&vp->v_lock, PVFS, "vnlock", 0, LK_NOPAUSE); 630 insmntque(vp, mp); 631 *vpp = vp; 632 vp->v_usecount = 1; 633 vp->v_data = 0; 634 635 splx(s); 636 637 vfs_object_create(vp, p, p->p_ucred); 638 639 vnodeallocs++; 640 if (vnodeallocs % vnoderecycleperiod == 0 && 641 freevnodes < vnoderecycleminfreevn && 642 vnoderecyclemintotalvn < numvnodes) { 643 /* Recycle vnodes. */ 644 cache_purgeleafdirs(vnoderecyclenumber); 645 } 646 647 return (0); 648 } 649 650 /* 651 * Move a vnode from one mount queue to another. 652 */ 653 static void 654 insmntque(vp, mp) 655 register struct vnode *vp; 656 register struct mount *mp; 657 { 658 659 mtx_lock(&mntvnode_mtx); 660 /* 661 * Delete from old mount point vnode list, if on one. 662 */ 663 if (vp->v_mount != NULL) 664 LIST_REMOVE(vp, v_mntvnodes); 665 /* 666 * Insert into list of vnodes for the new mount point, if available. 667 */ 668 if ((vp->v_mount = mp) == NULL) { 669 mtx_unlock(&mntvnode_mtx); 670 return; 671 } 672 LIST_INSERT_HEAD(&mp->mnt_vnodelist, vp, v_mntvnodes); 673 mtx_unlock(&mntvnode_mtx); 674 } 675 676 /* 677 * Update outstanding I/O count and do wakeup if requested. 678 */ 679 void 680 vwakeup(bp) 681 register struct buf *bp; 682 { 683 register struct vnode *vp; 684 685 bp->b_flags &= ~B_WRITEINPROG; 686 if ((vp = bp->b_vp)) { 687 vp->v_numoutput--; 688 if (vp->v_numoutput < 0) 689 panic("vwakeup: neg numoutput"); 690 if ((vp->v_numoutput == 0) && (vp->v_flag & VBWAIT)) { 691 vp->v_flag &= ~VBWAIT; 692 wakeup((caddr_t) &vp->v_numoutput); 693 } 694 } 695 } 696 697 /* 698 * Flush out and invalidate all buffers associated with a vnode. 699 * Called with the underlying object locked. 700 */ 701 int 702 vinvalbuf(vp, flags, cred, p, slpflag, slptimeo) 703 register struct vnode *vp; 704 int flags; 705 struct ucred *cred; 706 struct proc *p; 707 int slpflag, slptimeo; 708 { 709 register struct buf *bp; 710 struct buf *nbp, *blist; 711 int s, error; 712 vm_object_t object; 713 714 GIANT_REQUIRED; 715 716 if (flags & V_SAVE) { 717 s = splbio(); 718 while (vp->v_numoutput) { 719 vp->v_flag |= VBWAIT; 720 error = tsleep((caddr_t)&vp->v_numoutput, 721 slpflag | (PRIBIO + 1), "vinvlbuf", slptimeo); 722 if (error) { 723 splx(s); 724 return (error); 725 } 726 } 727 if (!TAILQ_EMPTY(&vp->v_dirtyblkhd)) { 728 splx(s); 729 if ((error = VOP_FSYNC(vp, cred, MNT_WAIT, p)) != 0) 730 return (error); 731 s = splbio(); 732 if (vp->v_numoutput > 0 || 733 !TAILQ_EMPTY(&vp->v_dirtyblkhd)) 734 panic("vinvalbuf: dirty bufs"); 735 } 736 splx(s); 737 } 738 s = splbio(); 739 for (;;) { 740 blist = TAILQ_FIRST(&vp->v_cleanblkhd); 741 if (!blist) 742 blist = TAILQ_FIRST(&vp->v_dirtyblkhd); 743 if (!blist) 744 break; 745 746 for (bp = blist; bp; bp = nbp) { 747 nbp = TAILQ_NEXT(bp, b_vnbufs); 748 if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_NOWAIT)) { 749 error = BUF_TIMELOCK(bp, 750 LK_EXCLUSIVE | LK_SLEEPFAIL, 751 "vinvalbuf", slpflag, slptimeo); 752 if (error == ENOLCK) 753 break; 754 splx(s); 755 return (error); 756 } 757 /* 758 * XXX Since there are no node locks for NFS, I 759 * believe there is a slight chance that a delayed 760 * write will occur while sleeping just above, so 761 * check for it. Note that vfs_bio_awrite expects 762 * buffers to reside on a queue, while BUF_WRITE and 763 * brelse do not. 764 */ 765 if (((bp->b_flags & (B_DELWRI | B_INVAL)) == B_DELWRI) && 766 (flags & V_SAVE)) { 767 768 if (bp->b_vp == vp) { 769 if (bp->b_flags & B_CLUSTEROK) { 770 BUF_UNLOCK(bp); 771 vfs_bio_awrite(bp); 772 } else { 773 bremfree(bp); 774 bp->b_flags |= B_ASYNC; 775 BUF_WRITE(bp); 776 } 777 } else { 778 bremfree(bp); 779 (void) BUF_WRITE(bp); 780 } 781 break; 782 } 783 bremfree(bp); 784 bp->b_flags |= (B_INVAL | B_NOCACHE | B_RELBUF); 785 bp->b_flags &= ~B_ASYNC; 786 brelse(bp); 787 } 788 } 789 790 while (vp->v_numoutput > 0) { 791 vp->v_flag |= VBWAIT; 792 tsleep(&vp->v_numoutput, PVM, "vnvlbv", 0); 793 } 794 795 splx(s); 796 797 /* 798 * Destroy the copy in the VM cache, too. 799 */ 800 mtx_lock(&vp->v_interlock); 801 if (VOP_GETVOBJECT(vp, &object) == 0) { 802 vm_object_page_remove(object, 0, 0, 803 (flags & V_SAVE) ? TRUE : FALSE); 804 } 805 mtx_unlock(&vp->v_interlock); 806 807 if (!TAILQ_EMPTY(&vp->v_dirtyblkhd) || !TAILQ_EMPTY(&vp->v_cleanblkhd)) 808 panic("vinvalbuf: flush failed"); 809 return (0); 810 } 811 812 /* 813 * Truncate a file's buffer and pages to a specified length. This 814 * is in lieu of the old vinvalbuf mechanism, which performed unneeded 815 * sync activity. 816 */ 817 int 818 vtruncbuf(vp, cred, p, length, blksize) 819 register struct vnode *vp; 820 struct ucred *cred; 821 struct proc *p; 822 off_t length; 823 int blksize; 824 { 825 register struct buf *bp; 826 struct buf *nbp; 827 int s, anyfreed; 828 int trunclbn; 829 830 /* 831 * Round up to the *next* lbn. 832 */ 833 trunclbn = (length + blksize - 1) / blksize; 834 835 s = splbio(); 836 restart: 837 anyfreed = 1; 838 for (;anyfreed;) { 839 anyfreed = 0; 840 for (bp = TAILQ_FIRST(&vp->v_cleanblkhd); bp; bp = nbp) { 841 nbp = TAILQ_NEXT(bp, b_vnbufs); 842 if (bp->b_lblkno >= trunclbn) { 843 if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_NOWAIT)) { 844 BUF_LOCK(bp, LK_EXCLUSIVE|LK_SLEEPFAIL); 845 goto restart; 846 } else { 847 bremfree(bp); 848 bp->b_flags |= (B_INVAL | B_RELBUF); 849 bp->b_flags &= ~B_ASYNC; 850 brelse(bp); 851 anyfreed = 1; 852 } 853 if (nbp && 854 (((nbp->b_xflags & BX_VNCLEAN) == 0) || 855 (nbp->b_vp != vp) || 856 (nbp->b_flags & B_DELWRI))) { 857 goto restart; 858 } 859 } 860 } 861 862 for (bp = TAILQ_FIRST(&vp->v_dirtyblkhd); bp; bp = nbp) { 863 nbp = TAILQ_NEXT(bp, b_vnbufs); 864 if (bp->b_lblkno >= trunclbn) { 865 if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_NOWAIT)) { 866 BUF_LOCK(bp, LK_EXCLUSIVE|LK_SLEEPFAIL); 867 goto restart; 868 } else { 869 bremfree(bp); 870 bp->b_flags |= (B_INVAL | B_RELBUF); 871 bp->b_flags &= ~B_ASYNC; 872 brelse(bp); 873 anyfreed = 1; 874 } 875 if (nbp && 876 (((nbp->b_xflags & BX_VNDIRTY) == 0) || 877 (nbp->b_vp != vp) || 878 (nbp->b_flags & B_DELWRI) == 0)) { 879 goto restart; 880 } 881 } 882 } 883 } 884 885 if (length > 0) { 886 restartsync: 887 for (bp = TAILQ_FIRST(&vp->v_dirtyblkhd); bp; bp = nbp) { 888 nbp = TAILQ_NEXT(bp, b_vnbufs); 889 if ((bp->b_flags & B_DELWRI) && (bp->b_lblkno < 0)) { 890 if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_NOWAIT)) { 891 BUF_LOCK(bp, LK_EXCLUSIVE|LK_SLEEPFAIL); 892 goto restart; 893 } else { 894 bremfree(bp); 895 if (bp->b_vp == vp) { 896 bp->b_flags |= B_ASYNC; 897 } else { 898 bp->b_flags &= ~B_ASYNC; 899 } 900 BUF_WRITE(bp); 901 } 902 goto restartsync; 903 } 904 905 } 906 } 907 908 while (vp->v_numoutput > 0) { 909 vp->v_flag |= VBWAIT; 910 tsleep(&vp->v_numoutput, PVM, "vbtrunc", 0); 911 } 912 913 splx(s); 914 915 vnode_pager_setsize(vp, length); 916 917 return (0); 918 } 919 920 /* 921 * Associate a buffer with a vnode. 922 */ 923 void 924 bgetvp(vp, bp) 925 register struct vnode *vp; 926 register struct buf *bp; 927 { 928 int s; 929 930 KASSERT(bp->b_vp == NULL, ("bgetvp: not free")); 931 932 vhold(vp); 933 bp->b_vp = vp; 934 bp->b_dev = vn_todev(vp); 935 /* 936 * Insert onto list for new vnode. 937 */ 938 s = splbio(); 939 bp->b_xflags |= BX_VNCLEAN; 940 bp->b_xflags &= ~BX_VNDIRTY; 941 TAILQ_INSERT_TAIL(&vp->v_cleanblkhd, bp, b_vnbufs); 942 splx(s); 943 } 944 945 /* 946 * Disassociate a buffer from a vnode. 947 */ 948 void 949 brelvp(bp) 950 register struct buf *bp; 951 { 952 struct vnode *vp; 953 struct buflists *listheadp; 954 int s; 955 956 KASSERT(bp->b_vp != NULL, ("brelvp: NULL")); 957 958 /* 959 * Delete from old vnode list, if on one. 960 */ 961 vp = bp->b_vp; 962 s = splbio(); 963 if (bp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN)) { 964 if (bp->b_xflags & BX_VNDIRTY) 965 listheadp = &vp->v_dirtyblkhd; 966 else 967 listheadp = &vp->v_cleanblkhd; 968 TAILQ_REMOVE(listheadp, bp, b_vnbufs); 969 bp->b_xflags &= ~(BX_VNDIRTY | BX_VNCLEAN); 970 } 971 if ((vp->v_flag & VONWORKLST) && TAILQ_EMPTY(&vp->v_dirtyblkhd)) { 972 vp->v_flag &= ~VONWORKLST; 973 LIST_REMOVE(vp, v_synclist); 974 } 975 splx(s); 976 bp->b_vp = (struct vnode *) 0; 977 vdrop(vp); 978 } 979 980 /* 981 * Add an item to the syncer work queue. 982 */ 983 static void 984 vn_syncer_add_to_worklist(struct vnode *vp, int delay) 985 { 986 int s, slot; 987 988 s = splbio(); 989 990 if (vp->v_flag & VONWORKLST) { 991 LIST_REMOVE(vp, v_synclist); 992 } 993 994 if (delay > syncer_maxdelay - 2) 995 delay = syncer_maxdelay - 2; 996 slot = (syncer_delayno + delay) & syncer_mask; 997 998 LIST_INSERT_HEAD(&syncer_workitem_pending[slot], vp, v_synclist); 999 vp->v_flag |= VONWORKLST; 1000 splx(s); 1001 } 1002 1003 struct proc *updateproc; 1004 static void sched_sync __P((void)); 1005 static struct kproc_desc up_kp = { 1006 "syncer", 1007 sched_sync, 1008 &updateproc 1009 }; 1010 SYSINIT(syncer, SI_SUB_KTHREAD_UPDATE, SI_ORDER_FIRST, kproc_start, &up_kp) 1011 1012 /* 1013 * System filesystem synchronizer daemon. 1014 */ 1015 void 1016 sched_sync(void) 1017 { 1018 struct synclist *slp; 1019 struct vnode *vp; 1020 struct mount *mp; 1021 long starttime; 1022 int s; 1023 struct proc *p = updateproc; 1024 1025 mtx_lock(&Giant); 1026 1027 EVENTHANDLER_REGISTER(shutdown_pre_sync, kproc_shutdown, p, 1028 SHUTDOWN_PRI_LAST); 1029 1030 for (;;) { 1031 kthread_suspend_check(p); 1032 1033 starttime = time_second; 1034 1035 /* 1036 * Push files whose dirty time has expired. Be careful 1037 * of interrupt race on slp queue. 1038 */ 1039 s = splbio(); 1040 slp = &syncer_workitem_pending[syncer_delayno]; 1041 syncer_delayno += 1; 1042 if (syncer_delayno == syncer_maxdelay) 1043 syncer_delayno = 0; 1044 splx(s); 1045 1046 while ((vp = LIST_FIRST(slp)) != NULL) { 1047 if (VOP_ISLOCKED(vp, NULL) == 0 && 1048 vn_start_write(vp, &mp, V_NOWAIT) == 0) { 1049 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p); 1050 (void) VOP_FSYNC(vp, p->p_ucred, MNT_LAZY, p); 1051 VOP_UNLOCK(vp, 0, p); 1052 vn_finished_write(mp); 1053 } 1054 s = splbio(); 1055 if (LIST_FIRST(slp) == vp) { 1056 /* 1057 * Note: v_tag VT_VFS vps can remain on the 1058 * worklist too with no dirty blocks, but 1059 * since sync_fsync() moves it to a different 1060 * slot we are safe. 1061 */ 1062 if (TAILQ_EMPTY(&vp->v_dirtyblkhd) && 1063 !vn_isdisk(vp, NULL)) 1064 panic("sched_sync: fsync failed vp %p tag %d", vp, vp->v_tag); 1065 /* 1066 * Put us back on the worklist. The worklist 1067 * routine will remove us from our current 1068 * position and then add us back in at a later 1069 * position. 1070 */ 1071 vn_syncer_add_to_worklist(vp, syncdelay); 1072 } 1073 splx(s); 1074 } 1075 1076 /* 1077 * Do soft update processing. 1078 */ 1079 #ifdef SOFTUPDATES 1080 softdep_process_worklist(NULL); 1081 #endif 1082 1083 /* 1084 * The variable rushjob allows the kernel to speed up the 1085 * processing of the filesystem syncer process. A rushjob 1086 * value of N tells the filesystem syncer to process the next 1087 * N seconds worth of work on its queue ASAP. Currently rushjob 1088 * is used by the soft update code to speed up the filesystem 1089 * syncer process when the incore state is getting so far 1090 * ahead of the disk that the kernel memory pool is being 1091 * threatened with exhaustion. 1092 */ 1093 if (rushjob > 0) { 1094 rushjob -= 1; 1095 continue; 1096 } 1097 /* 1098 * If it has taken us less than a second to process the 1099 * current work, then wait. Otherwise start right over 1100 * again. We can still lose time if any single round 1101 * takes more than two seconds, but it does not really 1102 * matter as we are just trying to generally pace the 1103 * filesystem activity. 1104 */ 1105 if (time_second == starttime) 1106 tsleep(&lbolt, PPAUSE, "syncer", 0); 1107 } 1108 } 1109 1110 /* 1111 * Request the syncer daemon to speed up its work. 1112 * We never push it to speed up more than half of its 1113 * normal turn time, otherwise it could take over the cpu. 1114 */ 1115 int 1116 speedup_syncer() 1117 { 1118 1119 mtx_lock_spin(&sched_lock); 1120 if (updateproc->p_wchan == &lbolt) 1121 setrunnable(updateproc); 1122 mtx_unlock_spin(&sched_lock); 1123 if (rushjob < syncdelay / 2) { 1124 rushjob += 1; 1125 stat_rush_requests += 1; 1126 return (1); 1127 } 1128 return(0); 1129 } 1130 1131 /* 1132 * Associate a p-buffer with a vnode. 1133 * 1134 * Also sets B_PAGING flag to indicate that vnode is not fully associated 1135 * with the buffer. i.e. the bp has not been linked into the vnode or 1136 * ref-counted. 1137 */ 1138 void 1139 pbgetvp(vp, bp) 1140 register struct vnode *vp; 1141 register struct buf *bp; 1142 { 1143 1144 KASSERT(bp->b_vp == NULL, ("pbgetvp: not free")); 1145 1146 bp->b_vp = vp; 1147 bp->b_flags |= B_PAGING; 1148 bp->b_dev = vn_todev(vp); 1149 } 1150 1151 /* 1152 * Disassociate a p-buffer from a vnode. 1153 */ 1154 void 1155 pbrelvp(bp) 1156 register struct buf *bp; 1157 { 1158 1159 KASSERT(bp->b_vp != NULL, ("pbrelvp: NULL")); 1160 1161 /* XXX REMOVE ME */ 1162 if (TAILQ_NEXT(bp, b_vnbufs) != NULL) { 1163 panic( 1164 "relpbuf(): b_vp was probably reassignbuf()d %p %x", 1165 bp, 1166 (int)bp->b_flags 1167 ); 1168 } 1169 bp->b_vp = (struct vnode *) 0; 1170 bp->b_flags &= ~B_PAGING; 1171 } 1172 1173 /* 1174 * Change the vnode a pager buffer is associated with. 1175 */ 1176 void 1177 pbreassignbuf(bp, newvp) 1178 struct buf *bp; 1179 struct vnode *newvp; 1180 { 1181 1182 KASSERT(bp->b_flags & B_PAGING, 1183 ("pbreassignbuf() on non phys bp %p", bp)); 1184 bp->b_vp = newvp; 1185 } 1186 1187 /* 1188 * Reassign a buffer from one vnode to another. 1189 * Used to assign file specific control information 1190 * (indirect blocks) to the vnode to which they belong. 1191 */ 1192 void 1193 reassignbuf(bp, newvp) 1194 register struct buf *bp; 1195 register struct vnode *newvp; 1196 { 1197 struct buflists *listheadp; 1198 int delay; 1199 int s; 1200 1201 if (newvp == NULL) { 1202 printf("reassignbuf: NULL"); 1203 return; 1204 } 1205 ++reassignbufcalls; 1206 1207 /* 1208 * B_PAGING flagged buffers cannot be reassigned because their vp 1209 * is not fully linked in. 1210 */ 1211 if (bp->b_flags & B_PAGING) 1212 panic("cannot reassign paging buffer"); 1213 1214 s = splbio(); 1215 /* 1216 * Delete from old vnode list, if on one. 1217 */ 1218 if (bp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN)) { 1219 if (bp->b_xflags & BX_VNDIRTY) 1220 listheadp = &bp->b_vp->v_dirtyblkhd; 1221 else 1222 listheadp = &bp->b_vp->v_cleanblkhd; 1223 TAILQ_REMOVE(listheadp, bp, b_vnbufs); 1224 bp->b_xflags &= ~(BX_VNDIRTY | BX_VNCLEAN); 1225 if (bp->b_vp != newvp) { 1226 vdrop(bp->b_vp); 1227 bp->b_vp = NULL; /* for clarification */ 1228 } 1229 } 1230 /* 1231 * If dirty, put on list of dirty buffers; otherwise insert onto list 1232 * of clean buffers. 1233 */ 1234 if (bp->b_flags & B_DELWRI) { 1235 struct buf *tbp; 1236 1237 listheadp = &newvp->v_dirtyblkhd; 1238 if ((newvp->v_flag & VONWORKLST) == 0) { 1239 switch (newvp->v_type) { 1240 case VDIR: 1241 delay = dirdelay; 1242 break; 1243 case VCHR: 1244 if (newvp->v_rdev->si_mountpoint != NULL) { 1245 delay = metadelay; 1246 break; 1247 } 1248 /* fall through */ 1249 default: 1250 delay = filedelay; 1251 } 1252 vn_syncer_add_to_worklist(newvp, delay); 1253 } 1254 bp->b_xflags |= BX_VNDIRTY; 1255 tbp = TAILQ_FIRST(listheadp); 1256 if (tbp == NULL || 1257 bp->b_lblkno == 0 || 1258 (bp->b_lblkno > 0 && tbp->b_lblkno < 0) || 1259 (bp->b_lblkno > 0 && bp->b_lblkno < tbp->b_lblkno)) { 1260 TAILQ_INSERT_HEAD(listheadp, bp, b_vnbufs); 1261 ++reassignbufsortgood; 1262 } else if (bp->b_lblkno < 0) { 1263 TAILQ_INSERT_TAIL(listheadp, bp, b_vnbufs); 1264 ++reassignbufsortgood; 1265 } else if (reassignbufmethod == 1) { 1266 /* 1267 * New sorting algorithm, only handle sequential case, 1268 * otherwise append to end (but before metadata) 1269 */ 1270 if ((tbp = gbincore(newvp, bp->b_lblkno - 1)) != NULL && 1271 (tbp->b_xflags & BX_VNDIRTY)) { 1272 /* 1273 * Found the best place to insert the buffer 1274 */ 1275 TAILQ_INSERT_AFTER(listheadp, tbp, bp, b_vnbufs); 1276 ++reassignbufsortgood; 1277 } else { 1278 /* 1279 * Missed, append to end, but before meta-data. 1280 * We know that the head buffer in the list is 1281 * not meta-data due to prior conditionals. 1282 * 1283 * Indirect effects: NFS second stage write 1284 * tends to wind up here, giving maximum 1285 * distance between the unstable write and the 1286 * commit rpc. 1287 */ 1288 tbp = TAILQ_LAST(listheadp, buflists); 1289 while (tbp && tbp->b_lblkno < 0) 1290 tbp = TAILQ_PREV(tbp, buflists, b_vnbufs); 1291 TAILQ_INSERT_AFTER(listheadp, tbp, bp, b_vnbufs); 1292 ++reassignbufsortbad; 1293 } 1294 } else { 1295 /* 1296 * Old sorting algorithm, scan queue and insert 1297 */ 1298 struct buf *ttbp; 1299 while ((ttbp = TAILQ_NEXT(tbp, b_vnbufs)) && 1300 (ttbp->b_lblkno < bp->b_lblkno)) { 1301 ++reassignbufloops; 1302 tbp = ttbp; 1303 } 1304 TAILQ_INSERT_AFTER(listheadp, tbp, bp, b_vnbufs); 1305 } 1306 } else { 1307 bp->b_xflags |= BX_VNCLEAN; 1308 TAILQ_INSERT_TAIL(&newvp->v_cleanblkhd, bp, b_vnbufs); 1309 if ((newvp->v_flag & VONWORKLST) && 1310 TAILQ_EMPTY(&newvp->v_dirtyblkhd)) { 1311 newvp->v_flag &= ~VONWORKLST; 1312 LIST_REMOVE(newvp, v_synclist); 1313 } 1314 } 1315 if (bp->b_vp != newvp) { 1316 bp->b_vp = newvp; 1317 vhold(bp->b_vp); 1318 } 1319 splx(s); 1320 } 1321 1322 /* 1323 * Create a vnode for a device. 1324 * Used for mounting the root file system. 1325 */ 1326 int 1327 bdevvp(dev, vpp) 1328 dev_t dev; 1329 struct vnode **vpp; 1330 { 1331 register struct vnode *vp; 1332 struct vnode *nvp; 1333 int error; 1334 1335 if (dev == NODEV) { 1336 *vpp = NULLVP; 1337 return (ENXIO); 1338 } 1339 if (vfinddev(dev, VCHR, vpp)) 1340 return (0); 1341 error = getnewvnode(VT_NON, (struct mount *)0, spec_vnodeop_p, &nvp); 1342 if (error) { 1343 *vpp = NULLVP; 1344 return (error); 1345 } 1346 vp = nvp; 1347 vp->v_type = VCHR; 1348 addalias(vp, dev); 1349 *vpp = vp; 1350 return (0); 1351 } 1352 1353 /* 1354 * Add vnode to the alias list hung off the dev_t. 1355 * 1356 * The reason for this gunk is that multiple vnodes can reference 1357 * the same physical device, so checking vp->v_usecount to see 1358 * how many users there are is inadequate; the v_usecount for 1359 * the vnodes need to be accumulated. vcount() does that. 1360 */ 1361 struct vnode * 1362 addaliasu(nvp, nvp_rdev) 1363 struct vnode *nvp; 1364 udev_t nvp_rdev; 1365 { 1366 struct vnode *ovp; 1367 vop_t **ops; 1368 dev_t dev; 1369 1370 if (nvp->v_type == VBLK) 1371 return (nvp); 1372 if (nvp->v_type != VCHR) 1373 panic("addaliasu on non-special vnode"); 1374 dev = udev2dev(nvp_rdev, 0); 1375 /* 1376 * Check to see if we have a bdevvp vnode with no associated 1377 * filesystem. If so, we want to associate the filesystem of 1378 * the new newly instigated vnode with the bdevvp vnode and 1379 * discard the newly created vnode rather than leaving the 1380 * bdevvp vnode lying around with no associated filesystem. 1381 */ 1382 if (vfinddev(dev, nvp->v_type, &ovp) == 0 || ovp->v_data != NULL) { 1383 addalias(nvp, dev); 1384 return (nvp); 1385 } 1386 /* 1387 * Discard unneeded vnode, but save its node specific data. 1388 * Note that if there is a lock, it is carried over in the 1389 * node specific data to the replacement vnode. 1390 */ 1391 vref(ovp); 1392 ovp->v_data = nvp->v_data; 1393 ovp->v_tag = nvp->v_tag; 1394 nvp->v_data = NULL; 1395 lockinit(&ovp->v_lock, PVFS, nvp->v_lock.lk_wmesg, 1396 nvp->v_lock.lk_timo, nvp->v_lock.lk_flags & LK_EXTFLG_MASK); 1397 if (nvp->v_vnlock) 1398 ovp->v_vnlock = &ovp->v_lock; 1399 ops = ovp->v_op; 1400 ovp->v_op = nvp->v_op; 1401 if (VOP_ISLOCKED(nvp, curproc)) { 1402 VOP_UNLOCK(nvp, 0, curproc); 1403 vn_lock(ovp, LK_EXCLUSIVE | LK_RETRY, curproc); 1404 } 1405 nvp->v_op = ops; 1406 insmntque(ovp, nvp->v_mount); 1407 vrele(nvp); 1408 vgone(nvp); 1409 return (ovp); 1410 } 1411 1412 /* This is a local helper function that do the same as addaliasu, but for a 1413 * dev_t instead of an udev_t. */ 1414 static void 1415 addalias(nvp, dev) 1416 struct vnode *nvp; 1417 dev_t dev; 1418 { 1419 1420 KASSERT(nvp->v_type == VCHR, ("addalias on non-special vnode")); 1421 nvp->v_rdev = dev; 1422 mtx_lock(&spechash_mtx); 1423 SLIST_INSERT_HEAD(&dev->si_hlist, nvp, v_specnext); 1424 mtx_unlock(&spechash_mtx); 1425 } 1426 1427 /* 1428 * Grab a particular vnode from the free list, increment its 1429 * reference count and lock it. The vnode lock bit is set if the 1430 * vnode is being eliminated in vgone. The process is awakened 1431 * when the transition is completed, and an error returned to 1432 * indicate that the vnode is no longer usable (possibly having 1433 * been changed to a new file system type). 1434 */ 1435 int 1436 vget(vp, flags, p) 1437 register struct vnode *vp; 1438 int flags; 1439 struct proc *p; 1440 { 1441 int error; 1442 1443 /* 1444 * If the vnode is in the process of being cleaned out for 1445 * another use, we wait for the cleaning to finish and then 1446 * return failure. Cleaning is determined by checking that 1447 * the VXLOCK flag is set. 1448 */ 1449 if ((flags & LK_INTERLOCK) == 0) 1450 mtx_lock(&vp->v_interlock); 1451 if (vp->v_flag & VXLOCK) { 1452 if (vp->v_vxproc == curproc) { 1453 printf("VXLOCK interlock avoided\n"); 1454 } else { 1455 vp->v_flag |= VXWANT; 1456 msleep((caddr_t)vp, &vp->v_interlock, PINOD | PDROP, 1457 "vget", 0); 1458 return (ENOENT); 1459 } 1460 } 1461 1462 vp->v_usecount++; 1463 1464 if (VSHOULDBUSY(vp)) 1465 vbusy(vp); 1466 if (flags & LK_TYPE_MASK) { 1467 if ((error = vn_lock(vp, flags | LK_INTERLOCK, p)) != 0) { 1468 /* 1469 * must expand vrele here because we do not want 1470 * to call VOP_INACTIVE if the reference count 1471 * drops back to zero since it was never really 1472 * active. We must remove it from the free list 1473 * before sleeping so that multiple processes do 1474 * not try to recycle it. 1475 */ 1476 mtx_lock(&vp->v_interlock); 1477 vp->v_usecount--; 1478 if (VSHOULDFREE(vp)) 1479 vfree(vp); 1480 mtx_unlock(&vp->v_interlock); 1481 } 1482 return (error); 1483 } 1484 mtx_unlock(&vp->v_interlock); 1485 return (0); 1486 } 1487 1488 /* 1489 * Increase the reference count of a vnode. 1490 */ 1491 void 1492 vref(struct vnode *vp) 1493 { 1494 mtx_lock(&vp->v_interlock); 1495 vp->v_usecount++; 1496 mtx_unlock(&vp->v_interlock); 1497 } 1498 1499 /* 1500 * Vnode put/release. 1501 * If count drops to zero, call inactive routine and return to freelist. 1502 */ 1503 void 1504 vrele(vp) 1505 struct vnode *vp; 1506 { 1507 struct proc *p = curproc; /* XXX */ 1508 1509 KASSERT(vp != NULL, ("vrele: null vp")); 1510 1511 mtx_lock(&vp->v_interlock); 1512 1513 /* Skip this v_writecount check if we're going to panic below. */ 1514 KASSERT(vp->v_writecount < vp->v_usecount || vp->v_usecount < 1, 1515 ("vrele: missed vn_close")); 1516 1517 if (vp->v_usecount > 1) { 1518 1519 vp->v_usecount--; 1520 mtx_unlock(&vp->v_interlock); 1521 1522 return; 1523 } 1524 1525 if (vp->v_usecount == 1) { 1526 1527 vp->v_usecount--; 1528 if (VSHOULDFREE(vp)) 1529 vfree(vp); 1530 /* 1531 * If we are doing a vput, the node is already locked, and we must 1532 * call VOP_INACTIVE with the node locked. So, in the case of 1533 * vrele, we explicitly lock the vnode before calling VOP_INACTIVE. 1534 */ 1535 if (vn_lock(vp, LK_EXCLUSIVE | LK_INTERLOCK, p) == 0) { 1536 VOP_INACTIVE(vp, p); 1537 } 1538 1539 } else { 1540 #ifdef DIAGNOSTIC 1541 vprint("vrele: negative ref count", vp); 1542 mtx_unlock(&vp->v_interlock); 1543 #endif 1544 panic("vrele: negative ref cnt"); 1545 } 1546 } 1547 1548 /* 1549 * Release an already locked vnode. This give the same effects as 1550 * unlock+vrele(), but takes less time and avoids releasing and 1551 * re-aquiring the lock (as vrele() aquires the lock internally.) 1552 */ 1553 void 1554 vput(vp) 1555 struct vnode *vp; 1556 { 1557 struct proc *p = curproc; /* XXX */ 1558 1559 GIANT_REQUIRED; 1560 1561 KASSERT(vp != NULL, ("vput: null vp")); 1562 mtx_lock(&vp->v_interlock); 1563 /* Skip this v_writecount check if we're going to panic below. */ 1564 KASSERT(vp->v_writecount < vp->v_usecount || vp->v_usecount < 1, 1565 ("vput: missed vn_close")); 1566 1567 if (vp->v_usecount > 1) { 1568 1569 vp->v_usecount--; 1570 VOP_UNLOCK(vp, LK_INTERLOCK, p); 1571 return; 1572 1573 } 1574 1575 if (vp->v_usecount == 1) { 1576 1577 vp->v_usecount--; 1578 if (VSHOULDFREE(vp)) 1579 vfree(vp); 1580 /* 1581 * If we are doing a vput, the node is already locked, and we must 1582 * call VOP_INACTIVE with the node locked. So, in the case of 1583 * vrele, we explicitly lock the vnode before calling VOP_INACTIVE. 1584 */ 1585 mtx_unlock(&vp->v_interlock); 1586 VOP_INACTIVE(vp, p); 1587 1588 } else { 1589 #ifdef DIAGNOSTIC 1590 vprint("vput: negative ref count", vp); 1591 #endif 1592 panic("vput: negative ref cnt"); 1593 } 1594 } 1595 1596 /* 1597 * Somebody doesn't want the vnode recycled. 1598 */ 1599 void 1600 vhold(vp) 1601 register struct vnode *vp; 1602 { 1603 int s; 1604 1605 s = splbio(); 1606 vp->v_holdcnt++; 1607 if (VSHOULDBUSY(vp)) 1608 vbusy(vp); 1609 splx(s); 1610 } 1611 1612 /* 1613 * Note that there is one less who cares about this vnode. vdrop() is the 1614 * opposite of vhold(). 1615 */ 1616 void 1617 vdrop(vp) 1618 register struct vnode *vp; 1619 { 1620 int s; 1621 1622 s = splbio(); 1623 if (vp->v_holdcnt <= 0) 1624 panic("vdrop: holdcnt"); 1625 vp->v_holdcnt--; 1626 if (VSHOULDFREE(vp)) 1627 vfree(vp); 1628 splx(s); 1629 } 1630 1631 /* 1632 * Remove any vnodes in the vnode table belonging to mount point mp. 1633 * 1634 * If FORCECLOSE is not specified, there should not be any active ones, 1635 * return error if any are found (nb: this is a user error, not a 1636 * system error). If FORCECLOSE is specified, detach any active vnodes 1637 * that are found. 1638 * 1639 * If WRITECLOSE is set, only flush out regular file vnodes open for 1640 * writing. 1641 * 1642 * SKIPSYSTEM causes any vnodes marked VSYSTEM to be skipped. 1643 * 1644 * `rootrefs' specifies the base reference count for the root vnode 1645 * of this filesystem. The root vnode is considered busy if its 1646 * v_usecount exceeds this value. On a successful return, vflush() 1647 * will call vrele() on the root vnode exactly rootrefs times. 1648 * If the SKIPSYSTEM or WRITECLOSE flags are specified, rootrefs must 1649 * be zero. 1650 */ 1651 #ifdef DIAGNOSTIC 1652 static int busyprt = 0; /* print out busy vnodes */ 1653 SYSCTL_INT(_debug, OID_AUTO, busyprt, CTLFLAG_RW, &busyprt, 0, ""); 1654 #endif 1655 1656 int 1657 vflush(mp, rootrefs, flags) 1658 struct mount *mp; 1659 int rootrefs; 1660 int flags; 1661 { 1662 struct proc *p = curproc; /* XXX */ 1663 struct vnode *vp, *nvp, *rootvp = NULL; 1664 int busy = 0, error; 1665 1666 if (rootrefs > 0) { 1667 KASSERT((flags & (SKIPSYSTEM | WRITECLOSE)) == 0, 1668 ("vflush: bad args")); 1669 /* 1670 * Get the filesystem root vnode. We can vput() it 1671 * immediately, since with rootrefs > 0, it won't go away. 1672 */ 1673 if ((error = VFS_ROOT(mp, &rootvp)) != 0) 1674 return (error); 1675 vput(rootvp); 1676 } 1677 mtx_lock(&mntvnode_mtx); 1678 loop: 1679 for (vp = LIST_FIRST(&mp->mnt_vnodelist); vp; vp = nvp) { 1680 /* 1681 * Make sure this vnode wasn't reclaimed in getnewvnode(). 1682 * Start over if it has (it won't be on the list anymore). 1683 */ 1684 if (vp->v_mount != mp) 1685 goto loop; 1686 nvp = LIST_NEXT(vp, v_mntvnodes); 1687 1688 mtx_unlock(&mntvnode_mtx); 1689 mtx_lock(&vp->v_interlock); 1690 /* 1691 * Skip over a vnodes marked VSYSTEM. 1692 */ 1693 if ((flags & SKIPSYSTEM) && (vp->v_flag & VSYSTEM)) { 1694 mtx_unlock(&vp->v_interlock); 1695 mtx_lock(&mntvnode_mtx); 1696 continue; 1697 } 1698 /* 1699 * If WRITECLOSE is set, only flush out regular file vnodes 1700 * open for writing. 1701 */ 1702 if ((flags & WRITECLOSE) && 1703 (vp->v_writecount == 0 || vp->v_type != VREG)) { 1704 mtx_unlock(&vp->v_interlock); 1705 mtx_lock(&mntvnode_mtx); 1706 continue; 1707 } 1708 1709 /* 1710 * With v_usecount == 0, all we need to do is clear out the 1711 * vnode data structures and we are done. 1712 */ 1713 if (vp->v_usecount == 0) { 1714 vgonel(vp, p); 1715 mtx_lock(&mntvnode_mtx); 1716 continue; 1717 } 1718 1719 /* 1720 * If FORCECLOSE is set, forcibly close the vnode. For block 1721 * or character devices, revert to an anonymous device. For 1722 * all other files, just kill them. 1723 */ 1724 if (flags & FORCECLOSE) { 1725 if (vp->v_type != VCHR) { 1726 vgonel(vp, p); 1727 } else { 1728 vclean(vp, 0, p); 1729 vp->v_op = spec_vnodeop_p; 1730 insmntque(vp, (struct mount *) 0); 1731 } 1732 mtx_lock(&mntvnode_mtx); 1733 continue; 1734 } 1735 #ifdef DIAGNOSTIC 1736 if (busyprt) 1737 vprint("vflush: busy vnode", vp); 1738 #endif 1739 mtx_unlock(&vp->v_interlock); 1740 mtx_lock(&mntvnode_mtx); 1741 busy++; 1742 } 1743 mtx_unlock(&mntvnode_mtx); 1744 if (rootrefs > 0 && (flags & FORCECLOSE) == 0) { 1745 /* 1746 * If just the root vnode is busy, and if its refcount 1747 * is equal to `rootrefs', then go ahead and kill it. 1748 */ 1749 mtx_lock(&rootvp->v_interlock); 1750 KASSERT(busy > 0, ("vflush: not busy")); 1751 KASSERT(rootvp->v_usecount >= rootrefs, ("vflush: rootrefs")); 1752 if (busy == 1 && rootvp->v_usecount == rootrefs) { 1753 vgonel(rootvp, p); 1754 busy = 0; 1755 } else 1756 mtx_unlock(&rootvp->v_interlock); 1757 } 1758 if (busy) 1759 return (EBUSY); 1760 for (; rootrefs > 0; rootrefs--) 1761 vrele(rootvp); 1762 return (0); 1763 } 1764 1765 /* 1766 * Disassociate the underlying file system from a vnode. 1767 */ 1768 static void 1769 vclean(vp, flags, p) 1770 struct vnode *vp; 1771 int flags; 1772 struct proc *p; 1773 { 1774 int active; 1775 1776 /* 1777 * Check to see if the vnode is in use. If so we have to reference it 1778 * before we clean it out so that its count cannot fall to zero and 1779 * generate a race against ourselves to recycle it. 1780 */ 1781 if ((active = vp->v_usecount)) 1782 vp->v_usecount++; 1783 1784 /* 1785 * Prevent the vnode from being recycled or brought into use while we 1786 * clean it out. 1787 */ 1788 if (vp->v_flag & VXLOCK) 1789 panic("vclean: deadlock"); 1790 vp->v_flag |= VXLOCK; 1791 vp->v_vxproc = curproc; 1792 /* 1793 * Even if the count is zero, the VOP_INACTIVE routine may still 1794 * have the object locked while it cleans it out. The VOP_LOCK 1795 * ensures that the VOP_INACTIVE routine is done with its work. 1796 * For active vnodes, it ensures that no other activity can 1797 * occur while the underlying object is being cleaned out. 1798 */ 1799 VOP_LOCK(vp, LK_DRAIN | LK_INTERLOCK, p); 1800 1801 /* 1802 * Clean out any buffers associated with the vnode. 1803 * If the flush fails, just toss the buffers. 1804 */ 1805 if (flags & DOCLOSE) { 1806 if (TAILQ_FIRST(&vp->v_dirtyblkhd) != NULL) 1807 (void) vn_write_suspend_wait(vp, NULL, V_WAIT); 1808 if (vinvalbuf(vp, V_SAVE, NOCRED, p, 0, 0) != 0) 1809 vinvalbuf(vp, 0, NOCRED, p, 0, 0); 1810 } 1811 1812 VOP_DESTROYVOBJECT(vp); 1813 1814 /* 1815 * If purging an active vnode, it must be closed and 1816 * deactivated before being reclaimed. Note that the 1817 * VOP_INACTIVE will unlock the vnode. 1818 */ 1819 if (active) { 1820 if (flags & DOCLOSE) 1821 VOP_CLOSE(vp, FNONBLOCK, NOCRED, p); 1822 VOP_INACTIVE(vp, p); 1823 } else { 1824 /* 1825 * Any other processes trying to obtain this lock must first 1826 * wait for VXLOCK to clear, then call the new lock operation. 1827 */ 1828 VOP_UNLOCK(vp, 0, p); 1829 } 1830 /* 1831 * Reclaim the vnode. 1832 */ 1833 if (VOP_RECLAIM(vp, p)) 1834 panic("vclean: cannot reclaim"); 1835 1836 if (active) { 1837 /* 1838 * Inline copy of vrele() since VOP_INACTIVE 1839 * has already been called. 1840 */ 1841 mtx_lock(&vp->v_interlock); 1842 if (--vp->v_usecount <= 0) { 1843 #ifdef DIAGNOSTIC 1844 if (vp->v_usecount < 0 || vp->v_writecount != 0) { 1845 vprint("vclean: bad ref count", vp); 1846 panic("vclean: ref cnt"); 1847 } 1848 #endif 1849 vfree(vp); 1850 } 1851 mtx_unlock(&vp->v_interlock); 1852 } 1853 1854 cache_purge(vp); 1855 vp->v_vnlock = NULL; 1856 lockdestroy(&vp->v_lock); 1857 1858 if (VSHOULDFREE(vp)) 1859 vfree(vp); 1860 1861 /* 1862 * Done with purge, notify sleepers of the grim news. 1863 */ 1864 vp->v_op = dead_vnodeop_p; 1865 vn_pollgone(vp); 1866 vp->v_tag = VT_NON; 1867 vp->v_flag &= ~VXLOCK; 1868 vp->v_vxproc = NULL; 1869 if (vp->v_flag & VXWANT) { 1870 vp->v_flag &= ~VXWANT; 1871 wakeup((caddr_t) vp); 1872 } 1873 } 1874 1875 /* 1876 * Eliminate all activity associated with the requested vnode 1877 * and with all vnodes aliased to the requested vnode. 1878 */ 1879 int 1880 vop_revoke(ap) 1881 struct vop_revoke_args /* { 1882 struct vnode *a_vp; 1883 int a_flags; 1884 } */ *ap; 1885 { 1886 struct vnode *vp, *vq; 1887 dev_t dev; 1888 1889 KASSERT((ap->a_flags & REVOKEALL) != 0, ("vop_revoke")); 1890 1891 vp = ap->a_vp; 1892 /* 1893 * If a vgone (or vclean) is already in progress, 1894 * wait until it is done and return. 1895 */ 1896 if (vp->v_flag & VXLOCK) { 1897 vp->v_flag |= VXWANT; 1898 msleep((caddr_t)vp, &vp->v_interlock, PINOD | PDROP, 1899 "vop_revokeall", 0); 1900 return (0); 1901 } 1902 dev = vp->v_rdev; 1903 for (;;) { 1904 mtx_lock(&spechash_mtx); 1905 vq = SLIST_FIRST(&dev->si_hlist); 1906 mtx_unlock(&spechash_mtx); 1907 if (!vq) 1908 break; 1909 vgone(vq); 1910 } 1911 return (0); 1912 } 1913 1914 /* 1915 * Recycle an unused vnode to the front of the free list. 1916 * Release the passed interlock if the vnode will be recycled. 1917 */ 1918 int 1919 vrecycle(vp, inter_lkp, p) 1920 struct vnode *vp; 1921 struct mtx *inter_lkp; 1922 struct proc *p; 1923 { 1924 1925 mtx_lock(&vp->v_interlock); 1926 if (vp->v_usecount == 0) { 1927 if (inter_lkp) { 1928 mtx_unlock(inter_lkp); 1929 } 1930 vgonel(vp, p); 1931 return (1); 1932 } 1933 mtx_unlock(&vp->v_interlock); 1934 return (0); 1935 } 1936 1937 /* 1938 * Eliminate all activity associated with a vnode 1939 * in preparation for reuse. 1940 */ 1941 void 1942 vgone(vp) 1943 register struct vnode *vp; 1944 { 1945 struct proc *p = curproc; /* XXX */ 1946 1947 mtx_lock(&vp->v_interlock); 1948 vgonel(vp, p); 1949 } 1950 1951 /* 1952 * vgone, with the vp interlock held. 1953 */ 1954 void 1955 vgonel(vp, p) 1956 struct vnode *vp; 1957 struct proc *p; 1958 { 1959 int s; 1960 1961 /* 1962 * If a vgone (or vclean) is already in progress, 1963 * wait until it is done and return. 1964 */ 1965 if (vp->v_flag & VXLOCK) { 1966 vp->v_flag |= VXWANT; 1967 msleep((caddr_t)vp, &vp->v_interlock, PINOD | PDROP, 1968 "vgone", 0); 1969 return; 1970 } 1971 1972 /* 1973 * Clean out the filesystem specific data. 1974 */ 1975 vclean(vp, DOCLOSE, p); 1976 mtx_lock(&vp->v_interlock); 1977 1978 /* 1979 * Delete from old mount point vnode list, if on one. 1980 */ 1981 if (vp->v_mount != NULL) 1982 insmntque(vp, (struct mount *)0); 1983 /* 1984 * If special device, remove it from special device alias list 1985 * if it is on one. 1986 */ 1987 if (vp->v_type == VCHR && vp->v_rdev != NULL && vp->v_rdev != NODEV) { 1988 mtx_lock(&spechash_mtx); 1989 SLIST_REMOVE(&vp->v_rdev->si_hlist, vp, vnode, v_specnext); 1990 freedev(vp->v_rdev); 1991 mtx_unlock(&spechash_mtx); 1992 vp->v_rdev = NULL; 1993 } 1994 1995 /* 1996 * If it is on the freelist and not already at the head, 1997 * move it to the head of the list. The test of the 1998 * VDOOMED flag and the reference count of zero is because 1999 * it will be removed from the free list by getnewvnode, 2000 * but will not have its reference count incremented until 2001 * after calling vgone. If the reference count were 2002 * incremented first, vgone would (incorrectly) try to 2003 * close the previous instance of the underlying object. 2004 */ 2005 if (vp->v_usecount == 0 && !(vp->v_flag & VDOOMED)) { 2006 s = splbio(); 2007 mtx_lock(&vnode_free_list_mtx); 2008 if (vp->v_flag & VFREE) 2009 TAILQ_REMOVE(&vnode_free_list, vp, v_freelist); 2010 else 2011 freevnodes++; 2012 vp->v_flag |= VFREE; 2013 TAILQ_INSERT_HEAD(&vnode_free_list, vp, v_freelist); 2014 mtx_unlock(&vnode_free_list_mtx); 2015 splx(s); 2016 } 2017 2018 vp->v_type = VBAD; 2019 mtx_unlock(&vp->v_interlock); 2020 } 2021 2022 /* 2023 * Lookup a vnode by device number. 2024 */ 2025 int 2026 vfinddev(dev, type, vpp) 2027 dev_t dev; 2028 enum vtype type; 2029 struct vnode **vpp; 2030 { 2031 struct vnode *vp; 2032 2033 mtx_lock(&spechash_mtx); 2034 SLIST_FOREACH(vp, &dev->si_hlist, v_specnext) { 2035 if (type == vp->v_type) { 2036 *vpp = vp; 2037 mtx_unlock(&spechash_mtx); 2038 return (1); 2039 } 2040 } 2041 mtx_unlock(&spechash_mtx); 2042 return (0); 2043 } 2044 2045 /* 2046 * Calculate the total number of references to a special device. 2047 */ 2048 int 2049 vcount(vp) 2050 struct vnode *vp; 2051 { 2052 struct vnode *vq; 2053 int count; 2054 2055 count = 0; 2056 mtx_lock(&spechash_mtx); 2057 SLIST_FOREACH(vq, &vp->v_rdev->si_hlist, v_specnext) 2058 count += vq->v_usecount; 2059 mtx_unlock(&spechash_mtx); 2060 return (count); 2061 } 2062 2063 /* 2064 * Same as above, but using the dev_t as argument 2065 */ 2066 int 2067 count_dev(dev) 2068 dev_t dev; 2069 { 2070 struct vnode *vp; 2071 2072 vp = SLIST_FIRST(&dev->si_hlist); 2073 if (vp == NULL) 2074 return (0); 2075 return(vcount(vp)); 2076 } 2077 2078 /* 2079 * Print out a description of a vnode. 2080 */ 2081 static char *typename[] = 2082 {"VNON", "VREG", "VDIR", "VBLK", "VCHR", "VLNK", "VSOCK", "VFIFO", "VBAD"}; 2083 2084 void 2085 vprint(label, vp) 2086 char *label; 2087 struct vnode *vp; 2088 { 2089 char buf[96]; 2090 2091 if (label != NULL) 2092 printf("%s: %p: ", label, (void *)vp); 2093 else 2094 printf("%p: ", (void *)vp); 2095 printf("type %s, usecount %d, writecount %d, refcount %d,", 2096 typename[vp->v_type], vp->v_usecount, vp->v_writecount, 2097 vp->v_holdcnt); 2098 buf[0] = '\0'; 2099 if (vp->v_flag & VROOT) 2100 strcat(buf, "|VROOT"); 2101 if (vp->v_flag & VTEXT) 2102 strcat(buf, "|VTEXT"); 2103 if (vp->v_flag & VSYSTEM) 2104 strcat(buf, "|VSYSTEM"); 2105 if (vp->v_flag & VXLOCK) 2106 strcat(buf, "|VXLOCK"); 2107 if (vp->v_flag & VXWANT) 2108 strcat(buf, "|VXWANT"); 2109 if (vp->v_flag & VBWAIT) 2110 strcat(buf, "|VBWAIT"); 2111 if (vp->v_flag & VDOOMED) 2112 strcat(buf, "|VDOOMED"); 2113 if (vp->v_flag & VFREE) 2114 strcat(buf, "|VFREE"); 2115 if (vp->v_flag & VOBJBUF) 2116 strcat(buf, "|VOBJBUF"); 2117 if (buf[0] != '\0') 2118 printf(" flags (%s)", &buf[1]); 2119 if (vp->v_data == NULL) { 2120 printf("\n"); 2121 } else { 2122 printf("\n\t"); 2123 VOP_PRINT(vp); 2124 } 2125 } 2126 2127 #ifdef DDB 2128 #include <ddb/ddb.h> 2129 /* 2130 * List all of the locked vnodes in the system. 2131 * Called when debugging the kernel. 2132 */ 2133 DB_SHOW_COMMAND(lockedvnodes, lockedvnodes) 2134 { 2135 struct proc *p = curproc; /* XXX */ 2136 struct mount *mp, *nmp; 2137 struct vnode *vp; 2138 2139 printf("Locked vnodes\n"); 2140 mtx_lock(&mountlist_mtx); 2141 for (mp = TAILQ_FIRST(&mountlist); mp != NULL; mp = nmp) { 2142 if (vfs_busy(mp, LK_NOWAIT, &mountlist_mtx, p)) { 2143 nmp = TAILQ_NEXT(mp, mnt_list); 2144 continue; 2145 } 2146 mtx_lock(&mntvnode_mtx); 2147 LIST_FOREACH(vp, &mp->mnt_vnodelist, v_mntvnodes) { 2148 if (VOP_ISLOCKED(vp, NULL)) 2149 vprint((char *)0, vp); 2150 } 2151 mtx_unlock(&mntvnode_mtx); 2152 mtx_lock(&mountlist_mtx); 2153 nmp = TAILQ_NEXT(mp, mnt_list); 2154 vfs_unbusy(mp, p); 2155 } 2156 mtx_unlock(&mountlist_mtx); 2157 } 2158 #endif 2159 2160 /* 2161 * Top level filesystem related information gathering. 2162 */ 2163 static int sysctl_ovfs_conf __P((SYSCTL_HANDLER_ARGS)); 2164 2165 static int 2166 vfs_sysctl(SYSCTL_HANDLER_ARGS) 2167 { 2168 int *name = (int *)arg1 - 1; /* XXX */ 2169 u_int namelen = arg2 + 1; /* XXX */ 2170 struct vfsconf *vfsp; 2171 2172 #if 1 || defined(COMPAT_PRELITE2) 2173 /* Resolve ambiguity between VFS_VFSCONF and VFS_GENERIC. */ 2174 if (namelen == 1) 2175 return (sysctl_ovfs_conf(oidp, arg1, arg2, req)); 2176 #endif 2177 2178 /* XXX the below code does not compile; vfs_sysctl does not exist. */ 2179 #ifdef notyet 2180 /* all sysctl names at this level are at least name and field */ 2181 if (namelen < 2) 2182 return (ENOTDIR); /* overloaded */ 2183 if (name[0] != VFS_GENERIC) { 2184 for (vfsp = vfsconf; vfsp; vfsp = vfsp->vfc_next) 2185 if (vfsp->vfc_typenum == name[0]) 2186 break; 2187 if (vfsp == NULL) 2188 return (EOPNOTSUPP); 2189 return ((*vfsp->vfc_vfsops->vfs_sysctl)(&name[1], namelen - 1, 2190 oldp, oldlenp, newp, newlen, p)); 2191 } 2192 #endif 2193 switch (name[1]) { 2194 case VFS_MAXTYPENUM: 2195 if (namelen != 2) 2196 return (ENOTDIR); 2197 return (SYSCTL_OUT(req, &maxvfsconf, sizeof(int))); 2198 case VFS_CONF: 2199 if (namelen != 3) 2200 return (ENOTDIR); /* overloaded */ 2201 for (vfsp = vfsconf; vfsp; vfsp = vfsp->vfc_next) 2202 if (vfsp->vfc_typenum == name[2]) 2203 break; 2204 if (vfsp == NULL) 2205 return (EOPNOTSUPP); 2206 return (SYSCTL_OUT(req, vfsp, sizeof *vfsp)); 2207 } 2208 return (EOPNOTSUPP); 2209 } 2210 2211 SYSCTL_NODE(_vfs, VFS_GENERIC, generic, CTLFLAG_RD, vfs_sysctl, 2212 "Generic filesystem"); 2213 2214 #if 1 || defined(COMPAT_PRELITE2) 2215 2216 static int 2217 sysctl_ovfs_conf(SYSCTL_HANDLER_ARGS) 2218 { 2219 int error; 2220 struct vfsconf *vfsp; 2221 struct ovfsconf ovfs; 2222 2223 for (vfsp = vfsconf; vfsp; vfsp = vfsp->vfc_next) { 2224 ovfs.vfc_vfsops = vfsp->vfc_vfsops; /* XXX used as flag */ 2225 strcpy(ovfs.vfc_name, vfsp->vfc_name); 2226 ovfs.vfc_index = vfsp->vfc_typenum; 2227 ovfs.vfc_refcount = vfsp->vfc_refcount; 2228 ovfs.vfc_flags = vfsp->vfc_flags; 2229 error = SYSCTL_OUT(req, &ovfs, sizeof ovfs); 2230 if (error) 2231 return error; 2232 } 2233 return 0; 2234 } 2235 2236 #endif /* 1 || COMPAT_PRELITE2 */ 2237 2238 #if COMPILING_LINT 2239 #define KINFO_VNODESLOP 10 2240 /* 2241 * Dump vnode list (via sysctl). 2242 * Copyout address of vnode followed by vnode. 2243 */ 2244 /* ARGSUSED */ 2245 static int 2246 sysctl_vnode(SYSCTL_HANDLER_ARGS) 2247 { 2248 struct proc *p = curproc; /* XXX */ 2249 struct mount *mp, *nmp; 2250 struct vnode *nvp, *vp; 2251 int error; 2252 2253 #define VPTRSZ sizeof (struct vnode *) 2254 #define VNODESZ sizeof (struct vnode) 2255 2256 req->lock = 0; 2257 if (!req->oldptr) /* Make an estimate */ 2258 return (SYSCTL_OUT(req, 0, 2259 (numvnodes + KINFO_VNODESLOP) * (VPTRSZ + VNODESZ))); 2260 2261 mtx_lock(&mountlist_mtx); 2262 for (mp = TAILQ_FIRST(&mountlist); mp != NULL; mp = nmp) { 2263 if (vfs_busy(mp, LK_NOWAIT, &mountlist_mtx, p)) { 2264 nmp = TAILQ_NEXT(mp, mnt_list); 2265 continue; 2266 } 2267 mtx_lock(&mntvnode_mtx); 2268 again: 2269 for (vp = LIST_FIRST(&mp->mnt_vnodelist); 2270 vp != NULL; 2271 vp = nvp) { 2272 /* 2273 * Check that the vp is still associated with 2274 * this filesystem. RACE: could have been 2275 * recycled onto the same filesystem. 2276 */ 2277 if (vp->v_mount != mp) 2278 goto again; 2279 nvp = LIST_NEXT(vp, v_mntvnodes); 2280 mtx_unlock(&mntvnode_mtx); 2281 if ((error = SYSCTL_OUT(req, &vp, VPTRSZ)) || 2282 (error = SYSCTL_OUT(req, vp, VNODESZ))) 2283 return (error); 2284 mtx_lock(&mntvnode_mtx); 2285 } 2286 mtx_unlock(&mntvnode_mtx); 2287 mtx_lock(&mountlist_mtx); 2288 nmp = TAILQ_NEXT(mp, mnt_list); 2289 vfs_unbusy(mp, p); 2290 } 2291 mtx_unlock(&mountlist_mtx); 2292 2293 return (0); 2294 } 2295 2296 /* 2297 * XXX 2298 * Exporting the vnode list on large systems causes them to crash. 2299 * Exporting the vnode list on medium systems causes sysctl to coredump. 2300 */ 2301 SYSCTL_PROC(_kern, KERN_VNODE, vnode, CTLTYPE_OPAQUE|CTLFLAG_RD, 2302 0, 0, sysctl_vnode, "S,vnode", ""); 2303 #endif 2304 2305 /* 2306 * Check to see if a filesystem is mounted on a block device. 2307 */ 2308 int 2309 vfs_mountedon(vp) 2310 struct vnode *vp; 2311 { 2312 2313 if (vp->v_rdev->si_mountpoint != NULL) 2314 return (EBUSY); 2315 return (0); 2316 } 2317 2318 /* 2319 * Unmount all filesystems. The list is traversed in reverse order 2320 * of mounting to avoid dependencies. 2321 */ 2322 void 2323 vfs_unmountall() 2324 { 2325 struct mount *mp; 2326 struct proc *p; 2327 int error; 2328 2329 if (curproc != NULL) 2330 p = curproc; 2331 else 2332 p = initproc; /* XXX XXX should this be proc0? */ 2333 /* 2334 * Since this only runs when rebooting, it is not interlocked. 2335 */ 2336 while(!TAILQ_EMPTY(&mountlist)) { 2337 mp = TAILQ_LAST(&mountlist, mntlist); 2338 error = dounmount(mp, MNT_FORCE, p); 2339 if (error) { 2340 TAILQ_REMOVE(&mountlist, mp, mnt_list); 2341 printf("unmount of %s failed (", 2342 mp->mnt_stat.f_mntonname); 2343 if (error == EBUSY) 2344 printf("BUSY)\n"); 2345 else 2346 printf("%d)\n", error); 2347 } else { 2348 /* The unmount has removed mp from the mountlist */ 2349 } 2350 } 2351 } 2352 2353 /* 2354 * perform msync on all vnodes under a mount point 2355 * the mount point must be locked. 2356 */ 2357 void 2358 vfs_msync(struct mount *mp, int flags) { 2359 struct vnode *vp, *nvp; 2360 struct vm_object *obj; 2361 int anyio, tries; 2362 2363 GIANT_REQUIRED; 2364 2365 tries = 5; 2366 loop: 2367 anyio = 0; 2368 mtx_lock(&mntvnode_mtx); 2369 for (vp = LIST_FIRST(&mp->mnt_vnodelist); vp != NULL; vp = nvp) { 2370 2371 nvp = LIST_NEXT(vp, v_mntvnodes); 2372 2373 if (vp->v_mount != mp) { 2374 mtx_unlock(&mntvnode_mtx); 2375 goto loop; 2376 } 2377 2378 if (vp->v_flag & VXLOCK) /* XXX: what if MNT_WAIT? */ 2379 continue; 2380 2381 if (vp->v_flag & VNOSYNC) /* unlinked, skip it */ 2382 continue; 2383 2384 if (flags != MNT_WAIT) { 2385 if (VOP_GETVOBJECT(vp, &obj) != 0 || 2386 (obj->flags & OBJ_MIGHTBEDIRTY) == 0) 2387 continue; 2388 if (VOP_ISLOCKED(vp, NULL)) 2389 continue; 2390 } 2391 2392 mtx_unlock(&mntvnode_mtx); 2393 mtx_lock(&vp->v_interlock); 2394 if (VOP_GETVOBJECT(vp, &obj) == 0 && 2395 (obj->flags & OBJ_MIGHTBEDIRTY)) { 2396 if (!vget(vp, 2397 LK_INTERLOCK | LK_EXCLUSIVE | LK_RETRY | LK_NOOBJ, curproc)) { 2398 if (VOP_GETVOBJECT(vp, &obj) == 0) { 2399 vm_object_page_clean(obj, 0, 0, 2400 flags == MNT_WAIT ? 2401 OBJPC_SYNC : OBJPC_NOSYNC); 2402 anyio = 1; 2403 } 2404 vput(vp); 2405 } 2406 } else { 2407 mtx_unlock(&vp->v_interlock); 2408 } 2409 mtx_lock(&mntvnode_mtx); 2410 } 2411 mtx_unlock(&mntvnode_mtx); 2412 if (anyio && (--tries > 0)) 2413 goto loop; 2414 } 2415 2416 /* 2417 * Create the VM object needed for VMIO and mmap support. This 2418 * is done for all VREG files in the system. Some filesystems might 2419 * afford the additional metadata buffering capability of the 2420 * VMIO code by making the device node be VMIO mode also. 2421 * 2422 * vp must be locked when vfs_object_create is called. 2423 */ 2424 int 2425 vfs_object_create(vp, p, cred) 2426 struct vnode *vp; 2427 struct proc *p; 2428 struct ucred *cred; 2429 { 2430 GIANT_REQUIRED; 2431 return (VOP_CREATEVOBJECT(vp, cred, p)); 2432 } 2433 2434 /* 2435 * Mark a vnode as free, putting it up for recycling. 2436 */ 2437 void 2438 vfree(vp) 2439 struct vnode *vp; 2440 { 2441 int s; 2442 2443 s = splbio(); 2444 mtx_lock(&vnode_free_list_mtx); 2445 KASSERT((vp->v_flag & VFREE) == 0, ("vnode already free")); 2446 if (vp->v_flag & VAGE) { 2447 TAILQ_INSERT_HEAD(&vnode_free_list, vp, v_freelist); 2448 } else { 2449 TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_freelist); 2450 } 2451 freevnodes++; 2452 mtx_unlock(&vnode_free_list_mtx); 2453 vp->v_flag &= ~VAGE; 2454 vp->v_flag |= VFREE; 2455 splx(s); 2456 } 2457 2458 /* 2459 * Opposite of vfree() - mark a vnode as in use. 2460 */ 2461 void 2462 vbusy(vp) 2463 struct vnode *vp; 2464 { 2465 int s; 2466 2467 s = splbio(); 2468 mtx_lock(&vnode_free_list_mtx); 2469 KASSERT((vp->v_flag & VFREE) != 0, ("vnode not free")); 2470 TAILQ_REMOVE(&vnode_free_list, vp, v_freelist); 2471 freevnodes--; 2472 mtx_unlock(&vnode_free_list_mtx); 2473 vp->v_flag &= ~(VFREE|VAGE); 2474 splx(s); 2475 } 2476 2477 /* 2478 * Record a process's interest in events which might happen to 2479 * a vnode. Because poll uses the historic select-style interface 2480 * internally, this routine serves as both the ``check for any 2481 * pending events'' and the ``record my interest in future events'' 2482 * functions. (These are done together, while the lock is held, 2483 * to avoid race conditions.) 2484 */ 2485 int 2486 vn_pollrecord(vp, p, events) 2487 struct vnode *vp; 2488 struct proc *p; 2489 short events; 2490 { 2491 mtx_lock(&vp->v_pollinfo.vpi_lock); 2492 if (vp->v_pollinfo.vpi_revents & events) { 2493 /* 2494 * This leaves events we are not interested 2495 * in available for the other process which 2496 * which presumably had requested them 2497 * (otherwise they would never have been 2498 * recorded). 2499 */ 2500 events &= vp->v_pollinfo.vpi_revents; 2501 vp->v_pollinfo.vpi_revents &= ~events; 2502 2503 mtx_unlock(&vp->v_pollinfo.vpi_lock); 2504 return events; 2505 } 2506 vp->v_pollinfo.vpi_events |= events; 2507 selrecord(p, &vp->v_pollinfo.vpi_selinfo); 2508 mtx_unlock(&vp->v_pollinfo.vpi_lock); 2509 return 0; 2510 } 2511 2512 /* 2513 * Note the occurrence of an event. If the VN_POLLEVENT macro is used, 2514 * it is possible for us to miss an event due to race conditions, but 2515 * that condition is expected to be rare, so for the moment it is the 2516 * preferred interface. 2517 */ 2518 void 2519 vn_pollevent(vp, events) 2520 struct vnode *vp; 2521 short events; 2522 { 2523 mtx_lock(&vp->v_pollinfo.vpi_lock); 2524 if (vp->v_pollinfo.vpi_events & events) { 2525 /* 2526 * We clear vpi_events so that we don't 2527 * call selwakeup() twice if two events are 2528 * posted before the polling process(es) is 2529 * awakened. This also ensures that we take at 2530 * most one selwakeup() if the polling process 2531 * is no longer interested. However, it does 2532 * mean that only one event can be noticed at 2533 * a time. (Perhaps we should only clear those 2534 * event bits which we note?) XXX 2535 */ 2536 vp->v_pollinfo.vpi_events = 0; /* &= ~events ??? */ 2537 vp->v_pollinfo.vpi_revents |= events; 2538 selwakeup(&vp->v_pollinfo.vpi_selinfo); 2539 } 2540 mtx_unlock(&vp->v_pollinfo.vpi_lock); 2541 } 2542 2543 #define VN_KNOTE(vp, b) \ 2544 KNOTE((struct klist *)&vp->v_pollinfo.vpi_selinfo.si_note, (b)) 2545 2546 /* 2547 * Wake up anyone polling on vp because it is being revoked. 2548 * This depends on dead_poll() returning POLLHUP for correct 2549 * behavior. 2550 */ 2551 void 2552 vn_pollgone(vp) 2553 struct vnode *vp; 2554 { 2555 mtx_lock(&vp->v_pollinfo.vpi_lock); 2556 VN_KNOTE(vp, NOTE_REVOKE); 2557 if (vp->v_pollinfo.vpi_events) { 2558 vp->v_pollinfo.vpi_events = 0; 2559 selwakeup(&vp->v_pollinfo.vpi_selinfo); 2560 } 2561 mtx_unlock(&vp->v_pollinfo.vpi_lock); 2562 } 2563 2564 2565 2566 /* 2567 * Routine to create and manage a filesystem syncer vnode. 2568 */ 2569 #define sync_close ((int (*) __P((struct vop_close_args *)))nullop) 2570 static int sync_fsync __P((struct vop_fsync_args *)); 2571 static int sync_inactive __P((struct vop_inactive_args *)); 2572 static int sync_reclaim __P((struct vop_reclaim_args *)); 2573 #define sync_lock ((int (*) __P((struct vop_lock_args *)))vop_nolock) 2574 #define sync_unlock ((int (*) __P((struct vop_unlock_args *)))vop_nounlock) 2575 static int sync_print __P((struct vop_print_args *)); 2576 #define sync_islocked ((int(*) __P((struct vop_islocked_args *)))vop_noislocked) 2577 2578 static vop_t **sync_vnodeop_p; 2579 static struct vnodeopv_entry_desc sync_vnodeop_entries[] = { 2580 { &vop_default_desc, (vop_t *) vop_eopnotsupp }, 2581 { &vop_close_desc, (vop_t *) sync_close }, /* close */ 2582 { &vop_fsync_desc, (vop_t *) sync_fsync }, /* fsync */ 2583 { &vop_inactive_desc, (vop_t *) sync_inactive }, /* inactive */ 2584 { &vop_reclaim_desc, (vop_t *) sync_reclaim }, /* reclaim */ 2585 { &vop_lock_desc, (vop_t *) sync_lock }, /* lock */ 2586 { &vop_unlock_desc, (vop_t *) sync_unlock }, /* unlock */ 2587 { &vop_print_desc, (vop_t *) sync_print }, /* print */ 2588 { &vop_islocked_desc, (vop_t *) sync_islocked }, /* islocked */ 2589 { NULL, NULL } 2590 }; 2591 static struct vnodeopv_desc sync_vnodeop_opv_desc = 2592 { &sync_vnodeop_p, sync_vnodeop_entries }; 2593 2594 VNODEOP_SET(sync_vnodeop_opv_desc); 2595 2596 /* 2597 * Create a new filesystem syncer vnode for the specified mount point. 2598 */ 2599 int 2600 vfs_allocate_syncvnode(mp) 2601 struct mount *mp; 2602 { 2603 struct vnode *vp; 2604 static long start, incr, next; 2605 int error; 2606 2607 /* Allocate a new vnode */ 2608 if ((error = getnewvnode(VT_VFS, mp, sync_vnodeop_p, &vp)) != 0) { 2609 mp->mnt_syncer = NULL; 2610 return (error); 2611 } 2612 vp->v_type = VNON; 2613 /* 2614 * Place the vnode onto the syncer worklist. We attempt to 2615 * scatter them about on the list so that they will go off 2616 * at evenly distributed times even if all the filesystems 2617 * are mounted at once. 2618 */ 2619 next += incr; 2620 if (next == 0 || next > syncer_maxdelay) { 2621 start /= 2; 2622 incr /= 2; 2623 if (start == 0) { 2624 start = syncer_maxdelay / 2; 2625 incr = syncer_maxdelay; 2626 } 2627 next = start; 2628 } 2629 vn_syncer_add_to_worklist(vp, syncdelay > 0 ? next % syncdelay : 0); 2630 mp->mnt_syncer = vp; 2631 return (0); 2632 } 2633 2634 /* 2635 * Do a lazy sync of the filesystem. 2636 */ 2637 static int 2638 sync_fsync(ap) 2639 struct vop_fsync_args /* { 2640 struct vnode *a_vp; 2641 struct ucred *a_cred; 2642 int a_waitfor; 2643 struct proc *a_p; 2644 } */ *ap; 2645 { 2646 struct vnode *syncvp = ap->a_vp; 2647 struct mount *mp = syncvp->v_mount; 2648 struct proc *p = ap->a_p; 2649 int asyncflag; 2650 2651 /* 2652 * We only need to do something if this is a lazy evaluation. 2653 */ 2654 if (ap->a_waitfor != MNT_LAZY) 2655 return (0); 2656 2657 /* 2658 * Move ourselves to the back of the sync list. 2659 */ 2660 vn_syncer_add_to_worklist(syncvp, syncdelay); 2661 2662 /* 2663 * Walk the list of vnodes pushing all that are dirty and 2664 * not already on the sync list. 2665 */ 2666 mtx_lock(&mountlist_mtx); 2667 if (vfs_busy(mp, LK_EXCLUSIVE | LK_NOWAIT, &mountlist_mtx, p) != 0) { 2668 mtx_unlock(&mountlist_mtx); 2669 return (0); 2670 } 2671 if (vn_start_write(NULL, &mp, V_NOWAIT) != 0) { 2672 vfs_unbusy(mp, p); 2673 return (0); 2674 } 2675 asyncflag = mp->mnt_flag & MNT_ASYNC; 2676 mp->mnt_flag &= ~MNT_ASYNC; 2677 vfs_msync(mp, MNT_NOWAIT); 2678 VFS_SYNC(mp, MNT_LAZY, ap->a_cred, p); 2679 if (asyncflag) 2680 mp->mnt_flag |= MNT_ASYNC; 2681 vn_finished_write(mp); 2682 vfs_unbusy(mp, p); 2683 return (0); 2684 } 2685 2686 /* 2687 * The syncer vnode is no referenced. 2688 */ 2689 static int 2690 sync_inactive(ap) 2691 struct vop_inactive_args /* { 2692 struct vnode *a_vp; 2693 struct proc *a_p; 2694 } */ *ap; 2695 { 2696 2697 vgone(ap->a_vp); 2698 return (0); 2699 } 2700 2701 /* 2702 * The syncer vnode is no longer needed and is being decommissioned. 2703 * 2704 * Modifications to the worklist must be protected at splbio(). 2705 */ 2706 static int 2707 sync_reclaim(ap) 2708 struct vop_reclaim_args /* { 2709 struct vnode *a_vp; 2710 } */ *ap; 2711 { 2712 struct vnode *vp = ap->a_vp; 2713 int s; 2714 2715 s = splbio(); 2716 vp->v_mount->mnt_syncer = NULL; 2717 if (vp->v_flag & VONWORKLST) { 2718 LIST_REMOVE(vp, v_synclist); 2719 vp->v_flag &= ~VONWORKLST; 2720 } 2721 splx(s); 2722 2723 return (0); 2724 } 2725 2726 /* 2727 * Print out a syncer vnode. 2728 */ 2729 static int 2730 sync_print(ap) 2731 struct vop_print_args /* { 2732 struct vnode *a_vp; 2733 } */ *ap; 2734 { 2735 struct vnode *vp = ap->a_vp; 2736 2737 printf("syncer vnode"); 2738 if (vp->v_vnlock != NULL) 2739 lockmgr_printinfo(vp->v_vnlock); 2740 printf("\n"); 2741 return (0); 2742 } 2743 2744 /* 2745 * extract the dev_t from a VCHR 2746 */ 2747 dev_t 2748 vn_todev(vp) 2749 struct vnode *vp; 2750 { 2751 if (vp->v_type != VCHR) 2752 return (NODEV); 2753 return (vp->v_rdev); 2754 } 2755 2756 /* 2757 * Check if vnode represents a disk device 2758 */ 2759 int 2760 vn_isdisk(vp, errp) 2761 struct vnode *vp; 2762 int *errp; 2763 { 2764 struct cdevsw *cdevsw; 2765 2766 if (vp->v_type != VCHR) { 2767 if (errp != NULL) 2768 *errp = ENOTBLK; 2769 return (0); 2770 } 2771 if (vp->v_rdev == NULL) { 2772 if (errp != NULL) 2773 *errp = ENXIO; 2774 return (0); 2775 } 2776 cdevsw = devsw(vp->v_rdev); 2777 if (cdevsw == NULL) { 2778 if (errp != NULL) 2779 *errp = ENXIO; 2780 return (0); 2781 } 2782 if (!(cdevsw->d_flags & D_DISK)) { 2783 if (errp != NULL) 2784 *errp = ENOTBLK; 2785 return (0); 2786 } 2787 if (errp != NULL) 2788 *errp = 0; 2789 return (1); 2790 } 2791 2792 /* 2793 * Free data allocated by namei(); see namei(9) for details. 2794 */ 2795 void 2796 NDFREE(ndp, flags) 2797 struct nameidata *ndp; 2798 const uint flags; 2799 { 2800 if (!(flags & NDF_NO_FREE_PNBUF) && 2801 (ndp->ni_cnd.cn_flags & HASBUF)) { 2802 zfree(namei_zone, ndp->ni_cnd.cn_pnbuf); 2803 ndp->ni_cnd.cn_flags &= ~HASBUF; 2804 } 2805 if (!(flags & NDF_NO_DVP_UNLOCK) && 2806 (ndp->ni_cnd.cn_flags & LOCKPARENT) && 2807 ndp->ni_dvp != ndp->ni_vp) 2808 VOP_UNLOCK(ndp->ni_dvp, 0, ndp->ni_cnd.cn_proc); 2809 if (!(flags & NDF_NO_DVP_RELE) && 2810 (ndp->ni_cnd.cn_flags & (LOCKPARENT|WANTPARENT))) { 2811 vrele(ndp->ni_dvp); 2812 ndp->ni_dvp = NULL; 2813 } 2814 if (!(flags & NDF_NO_VP_UNLOCK) && 2815 (ndp->ni_cnd.cn_flags & LOCKLEAF) && ndp->ni_vp) 2816 VOP_UNLOCK(ndp->ni_vp, 0, ndp->ni_cnd.cn_proc); 2817 if (!(flags & NDF_NO_VP_RELE) && 2818 ndp->ni_vp) { 2819 vrele(ndp->ni_vp); 2820 ndp->ni_vp = NULL; 2821 } 2822 if (!(flags & NDF_NO_STARTDIR_RELE) && 2823 (ndp->ni_cnd.cn_flags & SAVESTART)) { 2824 vrele(ndp->ni_startdir); 2825 ndp->ni_startdir = NULL; 2826 } 2827 } 2828 2829 /* 2830 * Common file system object access control check routine. Accepts a 2831 * vnode's type, "mode", uid and gid, requested access mode, credentials, 2832 * and optional call-by-reference privused argument allowing vaccess() 2833 * to indicate to the caller whether privilege was used to satisfy the 2834 * request. Returns 0 on success, or an errno on failure. 2835 */ 2836 int 2837 vaccess(type, file_mode, file_uid, file_gid, acc_mode, cred, privused) 2838 enum vtype type; 2839 mode_t file_mode; 2840 uid_t file_uid; 2841 gid_t file_gid; 2842 mode_t acc_mode; 2843 struct ucred *cred; 2844 int *privused; 2845 { 2846 mode_t dac_granted; 2847 #ifdef CAPABILITIES 2848 mode_t cap_granted; 2849 #endif 2850 2851 /* 2852 * Look for a normal, non-privileged way to access the file/directory 2853 * as requested. If it exists, go with that. 2854 */ 2855 2856 if (privused != NULL) 2857 *privused = 0; 2858 2859 dac_granted = 0; 2860 2861 /* Check the owner. */ 2862 if (cred->cr_uid == file_uid) { 2863 dac_granted |= VADMIN; 2864 if (file_mode & S_IXUSR) 2865 dac_granted |= VEXEC; 2866 if (file_mode & S_IRUSR) 2867 dac_granted |= VREAD; 2868 if (file_mode & S_IWUSR) 2869 dac_granted |= VWRITE; 2870 2871 if ((acc_mode & dac_granted) == acc_mode) 2872 return (0); 2873 2874 goto privcheck; 2875 } 2876 2877 /* Otherwise, check the groups (first match) */ 2878 if (groupmember(file_gid, cred)) { 2879 if (file_mode & S_IXGRP) 2880 dac_granted |= VEXEC; 2881 if (file_mode & S_IRGRP) 2882 dac_granted |= VREAD; 2883 if (file_mode & S_IWGRP) 2884 dac_granted |= VWRITE; 2885 2886 if ((acc_mode & dac_granted) == acc_mode) 2887 return (0); 2888 2889 goto privcheck; 2890 } 2891 2892 /* Otherwise, check everyone else. */ 2893 if (file_mode & S_IXOTH) 2894 dac_granted |= VEXEC; 2895 if (file_mode & S_IROTH) 2896 dac_granted |= VREAD; 2897 if (file_mode & S_IWOTH) 2898 dac_granted |= VWRITE; 2899 if ((acc_mode & dac_granted) == acc_mode) 2900 return (0); 2901 2902 privcheck: 2903 if (!suser_xxx(cred, NULL, PRISON_ROOT)) { 2904 /* XXX audit: privilege used */ 2905 if (privused != NULL) 2906 *privused = 1; 2907 return (0); 2908 } 2909 2910 #ifdef CAPABILITIES 2911 /* 2912 * Build a capability mask to determine if the set of capabilities 2913 * satisfies the requirements when combined with the granted mask 2914 * from above. 2915 * For each capability, if the capability is required, bitwise 2916 * or the request type onto the cap_granted mask. 2917 */ 2918 cap_granted = 0; 2919 if ((acc_mode & VEXEC) && ((dac_granted & VEXEC) == 0) && 2920 !cap_check_xxx(cred, NULL, CAP_DAC_EXECUTE, PRISON_ROOT)) 2921 cap_granted |= VEXEC; 2922 2923 if ((acc_mode & VREAD) && ((dac_granted & VREAD) == 0) && 2924 !cap_check_xxx(cred, NULL, CAP_DAC_READ_SEARCH, PRISON_ROOT)) 2925 cap_granted |= VREAD; 2926 2927 if ((acc_mode & VWRITE) && ((dac_granted & VWRITE) == 0) && 2928 !cap_check_xxx(cred, NULL, CAP_DAC_WRITE, PRISON_ROOT)) 2929 cap_granted |= VWRITE; 2930 2931 if ((acc_mode & VADMIN) && ((dac_granted & VADMIN) == 0) && 2932 !cap_check_xxx(cred, NULL, CAP_FOWNER, PRISON_ROOT)) 2933 cap_granted |= VADMIN; 2934 2935 if ((acc_mode & (cap_granted | dac_granted)) == acc_mode) { 2936 /* XXX audit: privilege used */ 2937 if (privused != NULL) 2938 *privused = 1; 2939 return (0); 2940 } 2941 #endif 2942 2943 return ((acc_mode & VADMIN) ? EPERM : EACCES); 2944 } 2945 2946