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 if (flags & V_SAVE) { 715 s = splbio(); 716 while (vp->v_numoutput) { 717 vp->v_flag |= VBWAIT; 718 error = tsleep((caddr_t)&vp->v_numoutput, 719 slpflag | (PRIBIO + 1), "vinvlbuf", slptimeo); 720 if (error) { 721 splx(s); 722 return (error); 723 } 724 } 725 if (!TAILQ_EMPTY(&vp->v_dirtyblkhd)) { 726 splx(s); 727 if ((error = VOP_FSYNC(vp, cred, MNT_WAIT, p)) != 0) 728 return (error); 729 s = splbio(); 730 if (vp->v_numoutput > 0 || 731 !TAILQ_EMPTY(&vp->v_dirtyblkhd)) 732 panic("vinvalbuf: dirty bufs"); 733 } 734 splx(s); 735 } 736 s = splbio(); 737 for (;;) { 738 blist = TAILQ_FIRST(&vp->v_cleanblkhd); 739 if (!blist) 740 blist = TAILQ_FIRST(&vp->v_dirtyblkhd); 741 if (!blist) 742 break; 743 744 for (bp = blist; bp; bp = nbp) { 745 nbp = TAILQ_NEXT(bp, b_vnbufs); 746 if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_NOWAIT)) { 747 error = BUF_TIMELOCK(bp, 748 LK_EXCLUSIVE | LK_SLEEPFAIL, 749 "vinvalbuf", slpflag, slptimeo); 750 if (error == ENOLCK) 751 break; 752 splx(s); 753 return (error); 754 } 755 /* 756 * XXX Since there are no node locks for NFS, I 757 * believe there is a slight chance that a delayed 758 * write will occur while sleeping just above, so 759 * check for it. Note that vfs_bio_awrite expects 760 * buffers to reside on a queue, while BUF_WRITE and 761 * brelse do not. 762 */ 763 if (((bp->b_flags & (B_DELWRI | B_INVAL)) == B_DELWRI) && 764 (flags & V_SAVE)) { 765 766 if (bp->b_vp == vp) { 767 if (bp->b_flags & B_CLUSTEROK) { 768 BUF_UNLOCK(bp); 769 vfs_bio_awrite(bp); 770 } else { 771 bremfree(bp); 772 bp->b_flags |= B_ASYNC; 773 BUF_WRITE(bp); 774 } 775 } else { 776 bremfree(bp); 777 (void) BUF_WRITE(bp); 778 } 779 break; 780 } 781 bremfree(bp); 782 bp->b_flags |= (B_INVAL | B_NOCACHE | B_RELBUF); 783 bp->b_flags &= ~B_ASYNC; 784 brelse(bp); 785 } 786 } 787 788 while (vp->v_numoutput > 0) { 789 vp->v_flag |= VBWAIT; 790 tsleep(&vp->v_numoutput, PVM, "vnvlbv", 0); 791 } 792 793 splx(s); 794 795 /* 796 * Destroy the copy in the VM cache, too. 797 */ 798 mtx_lock(&vp->v_interlock); 799 if (VOP_GETVOBJECT(vp, &object) == 0) { 800 vm_object_page_remove(object, 0, 0, 801 (flags & V_SAVE) ? TRUE : FALSE); 802 } 803 mtx_unlock(&vp->v_interlock); 804 805 if (!TAILQ_EMPTY(&vp->v_dirtyblkhd) || !TAILQ_EMPTY(&vp->v_cleanblkhd)) 806 panic("vinvalbuf: flush failed"); 807 return (0); 808 } 809 810 /* 811 * Truncate a file's buffer and pages to a specified length. This 812 * is in lieu of the old vinvalbuf mechanism, which performed unneeded 813 * sync activity. 814 */ 815 int 816 vtruncbuf(vp, cred, p, length, blksize) 817 register struct vnode *vp; 818 struct ucred *cred; 819 struct proc *p; 820 off_t length; 821 int blksize; 822 { 823 register struct buf *bp; 824 struct buf *nbp; 825 int s, anyfreed; 826 int trunclbn; 827 828 /* 829 * Round up to the *next* lbn. 830 */ 831 trunclbn = (length + blksize - 1) / blksize; 832 833 s = splbio(); 834 restart: 835 anyfreed = 1; 836 for (;anyfreed;) { 837 anyfreed = 0; 838 for (bp = TAILQ_FIRST(&vp->v_cleanblkhd); bp; bp = nbp) { 839 nbp = TAILQ_NEXT(bp, b_vnbufs); 840 if (bp->b_lblkno >= trunclbn) { 841 if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_NOWAIT)) { 842 BUF_LOCK(bp, LK_EXCLUSIVE|LK_SLEEPFAIL); 843 goto restart; 844 } else { 845 bremfree(bp); 846 bp->b_flags |= (B_INVAL | B_RELBUF); 847 bp->b_flags &= ~B_ASYNC; 848 brelse(bp); 849 anyfreed = 1; 850 } 851 if (nbp && 852 (((nbp->b_xflags & BX_VNCLEAN) == 0) || 853 (nbp->b_vp != vp) || 854 (nbp->b_flags & B_DELWRI))) { 855 goto restart; 856 } 857 } 858 } 859 860 for (bp = TAILQ_FIRST(&vp->v_dirtyblkhd); bp; bp = nbp) { 861 nbp = TAILQ_NEXT(bp, b_vnbufs); 862 if (bp->b_lblkno >= trunclbn) { 863 if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_NOWAIT)) { 864 BUF_LOCK(bp, LK_EXCLUSIVE|LK_SLEEPFAIL); 865 goto restart; 866 } else { 867 bremfree(bp); 868 bp->b_flags |= (B_INVAL | B_RELBUF); 869 bp->b_flags &= ~B_ASYNC; 870 brelse(bp); 871 anyfreed = 1; 872 } 873 if (nbp && 874 (((nbp->b_xflags & BX_VNDIRTY) == 0) || 875 (nbp->b_vp != vp) || 876 (nbp->b_flags & B_DELWRI) == 0)) { 877 goto restart; 878 } 879 } 880 } 881 } 882 883 if (length > 0) { 884 restartsync: 885 for (bp = TAILQ_FIRST(&vp->v_dirtyblkhd); bp; bp = nbp) { 886 nbp = TAILQ_NEXT(bp, b_vnbufs); 887 if ((bp->b_flags & B_DELWRI) && (bp->b_lblkno < 0)) { 888 if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_NOWAIT)) { 889 BUF_LOCK(bp, LK_EXCLUSIVE|LK_SLEEPFAIL); 890 goto restart; 891 } else { 892 bremfree(bp); 893 if (bp->b_vp == vp) { 894 bp->b_flags |= B_ASYNC; 895 } else { 896 bp->b_flags &= ~B_ASYNC; 897 } 898 BUF_WRITE(bp); 899 } 900 goto restartsync; 901 } 902 903 } 904 } 905 906 while (vp->v_numoutput > 0) { 907 vp->v_flag |= VBWAIT; 908 tsleep(&vp->v_numoutput, PVM, "vbtrunc", 0); 909 } 910 911 splx(s); 912 913 vnode_pager_setsize(vp, length); 914 915 return (0); 916 } 917 918 /* 919 * Associate a buffer with a vnode. 920 */ 921 void 922 bgetvp(vp, bp) 923 register struct vnode *vp; 924 register struct buf *bp; 925 { 926 int s; 927 928 KASSERT(bp->b_vp == NULL, ("bgetvp: not free")); 929 930 vhold(vp); 931 bp->b_vp = vp; 932 bp->b_dev = vn_todev(vp); 933 /* 934 * Insert onto list for new vnode. 935 */ 936 s = splbio(); 937 bp->b_xflags |= BX_VNCLEAN; 938 bp->b_xflags &= ~BX_VNDIRTY; 939 TAILQ_INSERT_TAIL(&vp->v_cleanblkhd, bp, b_vnbufs); 940 splx(s); 941 } 942 943 /* 944 * Disassociate a buffer from a vnode. 945 */ 946 void 947 brelvp(bp) 948 register struct buf *bp; 949 { 950 struct vnode *vp; 951 struct buflists *listheadp; 952 int s; 953 954 KASSERT(bp->b_vp != NULL, ("brelvp: NULL")); 955 956 /* 957 * Delete from old vnode list, if on one. 958 */ 959 vp = bp->b_vp; 960 s = splbio(); 961 if (bp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN)) { 962 if (bp->b_xflags & BX_VNDIRTY) 963 listheadp = &vp->v_dirtyblkhd; 964 else 965 listheadp = &vp->v_cleanblkhd; 966 TAILQ_REMOVE(listheadp, bp, b_vnbufs); 967 bp->b_xflags &= ~(BX_VNDIRTY | BX_VNCLEAN); 968 } 969 if ((vp->v_flag & VONWORKLST) && TAILQ_EMPTY(&vp->v_dirtyblkhd)) { 970 vp->v_flag &= ~VONWORKLST; 971 LIST_REMOVE(vp, v_synclist); 972 } 973 splx(s); 974 bp->b_vp = (struct vnode *) 0; 975 vdrop(vp); 976 } 977 978 /* 979 * Add an item to the syncer work queue. 980 */ 981 static void 982 vn_syncer_add_to_worklist(struct vnode *vp, int delay) 983 { 984 int s, slot; 985 986 s = splbio(); 987 988 if (vp->v_flag & VONWORKLST) { 989 LIST_REMOVE(vp, v_synclist); 990 } 991 992 if (delay > syncer_maxdelay - 2) 993 delay = syncer_maxdelay - 2; 994 slot = (syncer_delayno + delay) & syncer_mask; 995 996 LIST_INSERT_HEAD(&syncer_workitem_pending[slot], vp, v_synclist); 997 vp->v_flag |= VONWORKLST; 998 splx(s); 999 } 1000 1001 struct proc *updateproc; 1002 static void sched_sync __P((void)); 1003 static struct kproc_desc up_kp = { 1004 "syncer", 1005 sched_sync, 1006 &updateproc 1007 }; 1008 SYSINIT(syncer, SI_SUB_KTHREAD_UPDATE, SI_ORDER_FIRST, kproc_start, &up_kp) 1009 1010 /* 1011 * System filesystem synchronizer daemon. 1012 */ 1013 void 1014 sched_sync(void) 1015 { 1016 struct synclist *slp; 1017 struct vnode *vp; 1018 struct mount *mp; 1019 long starttime; 1020 int s; 1021 struct proc *p = updateproc; 1022 1023 mtx_lock(&Giant); 1024 1025 EVENTHANDLER_REGISTER(shutdown_pre_sync, kproc_shutdown, p, 1026 SHUTDOWN_PRI_LAST); 1027 1028 for (;;) { 1029 kthread_suspend_check(p); 1030 1031 starttime = time_second; 1032 1033 /* 1034 * Push files whose dirty time has expired. Be careful 1035 * of interrupt race on slp queue. 1036 */ 1037 s = splbio(); 1038 slp = &syncer_workitem_pending[syncer_delayno]; 1039 syncer_delayno += 1; 1040 if (syncer_delayno == syncer_maxdelay) 1041 syncer_delayno = 0; 1042 splx(s); 1043 1044 while ((vp = LIST_FIRST(slp)) != NULL) { 1045 if (VOP_ISLOCKED(vp, NULL) == 0 && 1046 vn_start_write(vp, &mp, V_NOWAIT) == 0) { 1047 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p); 1048 (void) VOP_FSYNC(vp, p->p_ucred, MNT_LAZY, p); 1049 VOP_UNLOCK(vp, 0, p); 1050 vn_finished_write(mp); 1051 } 1052 s = splbio(); 1053 if (LIST_FIRST(slp) == vp) { 1054 /* 1055 * Note: v_tag VT_VFS vps can remain on the 1056 * worklist too with no dirty blocks, but 1057 * since sync_fsync() moves it to a different 1058 * slot we are safe. 1059 */ 1060 if (TAILQ_EMPTY(&vp->v_dirtyblkhd) && 1061 !vn_isdisk(vp, NULL)) 1062 panic("sched_sync: fsync failed vp %p tag %d", vp, vp->v_tag); 1063 /* 1064 * Put us back on the worklist. The worklist 1065 * routine will remove us from our current 1066 * position and then add us back in at a later 1067 * position. 1068 */ 1069 vn_syncer_add_to_worklist(vp, syncdelay); 1070 } 1071 splx(s); 1072 } 1073 1074 /* 1075 * Do soft update processing. 1076 */ 1077 #ifdef SOFTUPDATES 1078 softdep_process_worklist(NULL); 1079 #endif 1080 1081 /* 1082 * The variable rushjob allows the kernel to speed up the 1083 * processing of the filesystem syncer process. A rushjob 1084 * value of N tells the filesystem syncer to process the next 1085 * N seconds worth of work on its queue ASAP. Currently rushjob 1086 * is used by the soft update code to speed up the filesystem 1087 * syncer process when the incore state is getting so far 1088 * ahead of the disk that the kernel memory pool is being 1089 * threatened with exhaustion. 1090 */ 1091 if (rushjob > 0) { 1092 rushjob -= 1; 1093 continue; 1094 } 1095 /* 1096 * If it has taken us less than a second to process the 1097 * current work, then wait. Otherwise start right over 1098 * again. We can still lose time if any single round 1099 * takes more than two seconds, but it does not really 1100 * matter as we are just trying to generally pace the 1101 * filesystem activity. 1102 */ 1103 if (time_second == starttime) 1104 tsleep(&lbolt, PPAUSE, "syncer", 0); 1105 } 1106 } 1107 1108 /* 1109 * Request the syncer daemon to speed up its work. 1110 * We never push it to speed up more than half of its 1111 * normal turn time, otherwise it could take over the cpu. 1112 */ 1113 int 1114 speedup_syncer() 1115 { 1116 1117 mtx_lock_spin(&sched_lock); 1118 if (updateproc->p_wchan == &lbolt) 1119 setrunnable(updateproc); 1120 mtx_unlock_spin(&sched_lock); 1121 if (rushjob < syncdelay / 2) { 1122 rushjob += 1; 1123 stat_rush_requests += 1; 1124 return (1); 1125 } 1126 return(0); 1127 } 1128 1129 /* 1130 * Associate a p-buffer with a vnode. 1131 * 1132 * Also sets B_PAGING flag to indicate that vnode is not fully associated 1133 * with the buffer. i.e. the bp has not been linked into the vnode or 1134 * ref-counted. 1135 */ 1136 void 1137 pbgetvp(vp, bp) 1138 register struct vnode *vp; 1139 register struct buf *bp; 1140 { 1141 1142 KASSERT(bp->b_vp == NULL, ("pbgetvp: not free")); 1143 1144 bp->b_vp = vp; 1145 bp->b_flags |= B_PAGING; 1146 bp->b_dev = vn_todev(vp); 1147 } 1148 1149 /* 1150 * Disassociate a p-buffer from a vnode. 1151 */ 1152 void 1153 pbrelvp(bp) 1154 register struct buf *bp; 1155 { 1156 1157 KASSERT(bp->b_vp != NULL, ("pbrelvp: NULL")); 1158 1159 /* XXX REMOVE ME */ 1160 if (TAILQ_NEXT(bp, b_vnbufs) != NULL) { 1161 panic( 1162 "relpbuf(): b_vp was probably reassignbuf()d %p %x", 1163 bp, 1164 (int)bp->b_flags 1165 ); 1166 } 1167 bp->b_vp = (struct vnode *) 0; 1168 bp->b_flags &= ~B_PAGING; 1169 } 1170 1171 /* 1172 * Change the vnode a pager buffer is associated with. 1173 */ 1174 void 1175 pbreassignbuf(bp, newvp) 1176 struct buf *bp; 1177 struct vnode *newvp; 1178 { 1179 1180 KASSERT(bp->b_flags & B_PAGING, 1181 ("pbreassignbuf() on non phys bp %p", bp)); 1182 bp->b_vp = newvp; 1183 } 1184 1185 /* 1186 * Reassign a buffer from one vnode to another. 1187 * Used to assign file specific control information 1188 * (indirect blocks) to the vnode to which they belong. 1189 */ 1190 void 1191 reassignbuf(bp, newvp) 1192 register struct buf *bp; 1193 register struct vnode *newvp; 1194 { 1195 struct buflists *listheadp; 1196 int delay; 1197 int s; 1198 1199 if (newvp == NULL) { 1200 printf("reassignbuf: NULL"); 1201 return; 1202 } 1203 ++reassignbufcalls; 1204 1205 /* 1206 * B_PAGING flagged buffers cannot be reassigned because their vp 1207 * is not fully linked in. 1208 */ 1209 if (bp->b_flags & B_PAGING) 1210 panic("cannot reassign paging buffer"); 1211 1212 s = splbio(); 1213 /* 1214 * Delete from old vnode list, if on one. 1215 */ 1216 if (bp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN)) { 1217 if (bp->b_xflags & BX_VNDIRTY) 1218 listheadp = &bp->b_vp->v_dirtyblkhd; 1219 else 1220 listheadp = &bp->b_vp->v_cleanblkhd; 1221 TAILQ_REMOVE(listheadp, bp, b_vnbufs); 1222 bp->b_xflags &= ~(BX_VNDIRTY | BX_VNCLEAN); 1223 if (bp->b_vp != newvp) { 1224 vdrop(bp->b_vp); 1225 bp->b_vp = NULL; /* for clarification */ 1226 } 1227 } 1228 /* 1229 * If dirty, put on list of dirty buffers; otherwise insert onto list 1230 * of clean buffers. 1231 */ 1232 if (bp->b_flags & B_DELWRI) { 1233 struct buf *tbp; 1234 1235 listheadp = &newvp->v_dirtyblkhd; 1236 if ((newvp->v_flag & VONWORKLST) == 0) { 1237 switch (newvp->v_type) { 1238 case VDIR: 1239 delay = dirdelay; 1240 break; 1241 case VCHR: 1242 if (newvp->v_rdev->si_mountpoint != NULL) { 1243 delay = metadelay; 1244 break; 1245 } 1246 /* fall through */ 1247 default: 1248 delay = filedelay; 1249 } 1250 vn_syncer_add_to_worklist(newvp, delay); 1251 } 1252 bp->b_xflags |= BX_VNDIRTY; 1253 tbp = TAILQ_FIRST(listheadp); 1254 if (tbp == NULL || 1255 bp->b_lblkno == 0 || 1256 (bp->b_lblkno > 0 && tbp->b_lblkno < 0) || 1257 (bp->b_lblkno > 0 && bp->b_lblkno < tbp->b_lblkno)) { 1258 TAILQ_INSERT_HEAD(listheadp, bp, b_vnbufs); 1259 ++reassignbufsortgood; 1260 } else if (bp->b_lblkno < 0) { 1261 TAILQ_INSERT_TAIL(listheadp, bp, b_vnbufs); 1262 ++reassignbufsortgood; 1263 } else if (reassignbufmethod == 1) { 1264 /* 1265 * New sorting algorithm, only handle sequential case, 1266 * otherwise append to end (but before metadata) 1267 */ 1268 if ((tbp = gbincore(newvp, bp->b_lblkno - 1)) != NULL && 1269 (tbp->b_xflags & BX_VNDIRTY)) { 1270 /* 1271 * Found the best place to insert the buffer 1272 */ 1273 TAILQ_INSERT_AFTER(listheadp, tbp, bp, b_vnbufs); 1274 ++reassignbufsortgood; 1275 } else { 1276 /* 1277 * Missed, append to end, but before meta-data. 1278 * We know that the head buffer in the list is 1279 * not meta-data due to prior conditionals. 1280 * 1281 * Indirect effects: NFS second stage write 1282 * tends to wind up here, giving maximum 1283 * distance between the unstable write and the 1284 * commit rpc. 1285 */ 1286 tbp = TAILQ_LAST(listheadp, buflists); 1287 while (tbp && tbp->b_lblkno < 0) 1288 tbp = TAILQ_PREV(tbp, buflists, b_vnbufs); 1289 TAILQ_INSERT_AFTER(listheadp, tbp, bp, b_vnbufs); 1290 ++reassignbufsortbad; 1291 } 1292 } else { 1293 /* 1294 * Old sorting algorithm, scan queue and insert 1295 */ 1296 struct buf *ttbp; 1297 while ((ttbp = TAILQ_NEXT(tbp, b_vnbufs)) && 1298 (ttbp->b_lblkno < bp->b_lblkno)) { 1299 ++reassignbufloops; 1300 tbp = ttbp; 1301 } 1302 TAILQ_INSERT_AFTER(listheadp, tbp, bp, b_vnbufs); 1303 } 1304 } else { 1305 bp->b_xflags |= BX_VNCLEAN; 1306 TAILQ_INSERT_TAIL(&newvp->v_cleanblkhd, bp, b_vnbufs); 1307 if ((newvp->v_flag & VONWORKLST) && 1308 TAILQ_EMPTY(&newvp->v_dirtyblkhd)) { 1309 newvp->v_flag &= ~VONWORKLST; 1310 LIST_REMOVE(newvp, v_synclist); 1311 } 1312 } 1313 if (bp->b_vp != newvp) { 1314 bp->b_vp = newvp; 1315 vhold(bp->b_vp); 1316 } 1317 splx(s); 1318 } 1319 1320 /* 1321 * Create a vnode for a device. 1322 * Used for mounting the root file system. 1323 */ 1324 int 1325 bdevvp(dev, vpp) 1326 dev_t dev; 1327 struct vnode **vpp; 1328 { 1329 register struct vnode *vp; 1330 struct vnode *nvp; 1331 int error; 1332 1333 if (dev == NODEV) { 1334 *vpp = NULLVP; 1335 return (ENXIO); 1336 } 1337 if (vfinddev(dev, VCHR, vpp)) 1338 return (0); 1339 error = getnewvnode(VT_NON, (struct mount *)0, spec_vnodeop_p, &nvp); 1340 if (error) { 1341 *vpp = NULLVP; 1342 return (error); 1343 } 1344 vp = nvp; 1345 vp->v_type = VCHR; 1346 addalias(vp, dev); 1347 *vpp = vp; 1348 return (0); 1349 } 1350 1351 /* 1352 * Add vnode to the alias list hung off the dev_t. 1353 * 1354 * The reason for this gunk is that multiple vnodes can reference 1355 * the same physical device, so checking vp->v_usecount to see 1356 * how many users there are is inadequate; the v_usecount for 1357 * the vnodes need to be accumulated. vcount() does that. 1358 */ 1359 struct vnode * 1360 addaliasu(nvp, nvp_rdev) 1361 struct vnode *nvp; 1362 udev_t nvp_rdev; 1363 { 1364 struct vnode *ovp; 1365 vop_t **ops; 1366 dev_t dev; 1367 1368 if (nvp->v_type == VBLK) 1369 return (nvp); 1370 if (nvp->v_type != VCHR) 1371 panic("addaliasu on non-special vnode"); 1372 dev = udev2dev(nvp_rdev, 0); 1373 /* 1374 * Check to see if we have a bdevvp vnode with no associated 1375 * filesystem. If so, we want to associate the filesystem of 1376 * the new newly instigated vnode with the bdevvp vnode and 1377 * discard the newly created vnode rather than leaving the 1378 * bdevvp vnode lying around with no associated filesystem. 1379 */ 1380 if (vfinddev(dev, nvp->v_type, &ovp) == 0 || ovp->v_data != NULL) { 1381 addalias(nvp, dev); 1382 return (nvp); 1383 } 1384 /* 1385 * Discard unneeded vnode, but save its node specific data. 1386 * Note that if there is a lock, it is carried over in the 1387 * node specific data to the replacement vnode. 1388 */ 1389 vref(ovp); 1390 ovp->v_data = nvp->v_data; 1391 ovp->v_tag = nvp->v_tag; 1392 nvp->v_data = NULL; 1393 lockinit(&ovp->v_lock, PVFS, nvp->v_lock.lk_wmesg, 1394 nvp->v_lock.lk_timo, nvp->v_lock.lk_flags & LK_EXTFLG_MASK); 1395 if (nvp->v_vnlock) 1396 ovp->v_vnlock = &ovp->v_lock; 1397 ops = ovp->v_op; 1398 ovp->v_op = nvp->v_op; 1399 if (VOP_ISLOCKED(nvp, curproc)) { 1400 VOP_UNLOCK(nvp, 0, curproc); 1401 vn_lock(ovp, LK_EXCLUSIVE | LK_RETRY, curproc); 1402 } 1403 nvp->v_op = ops; 1404 insmntque(ovp, nvp->v_mount); 1405 vrele(nvp); 1406 vgone(nvp); 1407 return (ovp); 1408 } 1409 1410 /* This is a local helper function that do the same as addaliasu, but for a 1411 * dev_t instead of an udev_t. */ 1412 static void 1413 addalias(nvp, dev) 1414 struct vnode *nvp; 1415 dev_t dev; 1416 { 1417 1418 KASSERT(nvp->v_type == VCHR, ("addalias on non-special vnode")); 1419 nvp->v_rdev = dev; 1420 mtx_lock(&spechash_mtx); 1421 SLIST_INSERT_HEAD(&dev->si_hlist, nvp, v_specnext); 1422 mtx_unlock(&spechash_mtx); 1423 } 1424 1425 /* 1426 * Grab a particular vnode from the free list, increment its 1427 * reference count and lock it. The vnode lock bit is set if the 1428 * vnode is being eliminated in vgone. The process is awakened 1429 * when the transition is completed, and an error returned to 1430 * indicate that the vnode is no longer usable (possibly having 1431 * been changed to a new file system type). 1432 */ 1433 int 1434 vget(vp, flags, p) 1435 register struct vnode *vp; 1436 int flags; 1437 struct proc *p; 1438 { 1439 int error; 1440 1441 /* 1442 * If the vnode is in the process of being cleaned out for 1443 * another use, we wait for the cleaning to finish and then 1444 * return failure. Cleaning is determined by checking that 1445 * the VXLOCK flag is set. 1446 */ 1447 if ((flags & LK_INTERLOCK) == 0) 1448 mtx_lock(&vp->v_interlock); 1449 if (vp->v_flag & VXLOCK) { 1450 if (vp->v_vxproc == curproc) { 1451 printf("VXLOCK interlock avoided\n"); 1452 } else { 1453 vp->v_flag |= VXWANT; 1454 msleep((caddr_t)vp, &vp->v_interlock, PINOD | PDROP, 1455 "vget", 0); 1456 return (ENOENT); 1457 } 1458 } 1459 1460 vp->v_usecount++; 1461 1462 if (VSHOULDBUSY(vp)) 1463 vbusy(vp); 1464 if (flags & LK_TYPE_MASK) { 1465 if ((error = vn_lock(vp, flags | LK_INTERLOCK, p)) != 0) { 1466 /* 1467 * must expand vrele here because we do not want 1468 * to call VOP_INACTIVE if the reference count 1469 * drops back to zero since it was never really 1470 * active. We must remove it from the free list 1471 * before sleeping so that multiple processes do 1472 * not try to recycle it. 1473 */ 1474 mtx_lock(&vp->v_interlock); 1475 vp->v_usecount--; 1476 if (VSHOULDFREE(vp)) 1477 vfree(vp); 1478 mtx_unlock(&vp->v_interlock); 1479 } 1480 return (error); 1481 } 1482 mtx_unlock(&vp->v_interlock); 1483 return (0); 1484 } 1485 1486 /* 1487 * Increase the reference count of a vnode. 1488 */ 1489 void 1490 vref(struct vnode *vp) 1491 { 1492 mtx_lock(&vp->v_interlock); 1493 vp->v_usecount++; 1494 mtx_unlock(&vp->v_interlock); 1495 } 1496 1497 /* 1498 * Vnode put/release. 1499 * If count drops to zero, call inactive routine and return to freelist. 1500 */ 1501 void 1502 vrele(vp) 1503 struct vnode *vp; 1504 { 1505 struct proc *p = curproc; /* XXX */ 1506 1507 KASSERT(vp != NULL, ("vrele: null vp")); 1508 1509 mtx_lock(&vp->v_interlock); 1510 1511 /* Skip this v_writecount check if we're going to panic below. */ 1512 KASSERT(vp->v_writecount < vp->v_usecount || vp->v_usecount < 1, 1513 ("vrele: missed vn_close")); 1514 1515 if (vp->v_usecount > 1) { 1516 1517 vp->v_usecount--; 1518 mtx_unlock(&vp->v_interlock); 1519 1520 return; 1521 } 1522 1523 if (vp->v_usecount == 1) { 1524 1525 vp->v_usecount--; 1526 if (VSHOULDFREE(vp)) 1527 vfree(vp); 1528 /* 1529 * If we are doing a vput, the node is already locked, and we must 1530 * call VOP_INACTIVE with the node locked. So, in the case of 1531 * vrele, we explicitly lock the vnode before calling VOP_INACTIVE. 1532 */ 1533 if (vn_lock(vp, LK_EXCLUSIVE | LK_INTERLOCK, p) == 0) { 1534 VOP_INACTIVE(vp, p); 1535 } 1536 1537 } else { 1538 #ifdef DIAGNOSTIC 1539 vprint("vrele: negative ref count", vp); 1540 mtx_unlock(&vp->v_interlock); 1541 #endif 1542 panic("vrele: negative ref cnt"); 1543 } 1544 } 1545 1546 /* 1547 * Release an already locked vnode. This give the same effects as 1548 * unlock+vrele(), but takes less time and avoids releasing and 1549 * re-aquiring the lock (as vrele() aquires the lock internally.) 1550 */ 1551 void 1552 vput(vp) 1553 struct vnode *vp; 1554 { 1555 struct proc *p = curproc; /* XXX */ 1556 1557 KASSERT(vp != NULL, ("vput: null vp")); 1558 mtx_lock(&vp->v_interlock); 1559 /* Skip this v_writecount check if we're going to panic below. */ 1560 KASSERT(vp->v_writecount < vp->v_usecount || vp->v_usecount < 1, 1561 ("vput: missed vn_close")); 1562 1563 if (vp->v_usecount > 1) { 1564 1565 vp->v_usecount--; 1566 VOP_UNLOCK(vp, LK_INTERLOCK, p); 1567 return; 1568 1569 } 1570 1571 if (vp->v_usecount == 1) { 1572 1573 vp->v_usecount--; 1574 if (VSHOULDFREE(vp)) 1575 vfree(vp); 1576 /* 1577 * If we are doing a vput, the node is already locked, and we must 1578 * call VOP_INACTIVE with the node locked. So, in the case of 1579 * vrele, we explicitly lock the vnode before calling VOP_INACTIVE. 1580 */ 1581 mtx_unlock(&vp->v_interlock); 1582 VOP_INACTIVE(vp, p); 1583 1584 } else { 1585 #ifdef DIAGNOSTIC 1586 vprint("vput: negative ref count", vp); 1587 #endif 1588 panic("vput: negative ref cnt"); 1589 } 1590 } 1591 1592 /* 1593 * Somebody doesn't want the vnode recycled. 1594 */ 1595 void 1596 vhold(vp) 1597 register struct vnode *vp; 1598 { 1599 int s; 1600 1601 s = splbio(); 1602 vp->v_holdcnt++; 1603 if (VSHOULDBUSY(vp)) 1604 vbusy(vp); 1605 splx(s); 1606 } 1607 1608 /* 1609 * Note that there is one less who cares about this vnode. vdrop() is the 1610 * opposite of vhold(). 1611 */ 1612 void 1613 vdrop(vp) 1614 register struct vnode *vp; 1615 { 1616 int s; 1617 1618 s = splbio(); 1619 if (vp->v_holdcnt <= 0) 1620 panic("vdrop: holdcnt"); 1621 vp->v_holdcnt--; 1622 if (VSHOULDFREE(vp)) 1623 vfree(vp); 1624 splx(s); 1625 } 1626 1627 /* 1628 * Remove any vnodes in the vnode table belonging to mount point mp. 1629 * 1630 * If MNT_NOFORCE is specified, there should not be any active ones, 1631 * return error if any are found (nb: this is a user error, not a 1632 * system error). If MNT_FORCE is specified, detach any active vnodes 1633 * that are found. 1634 */ 1635 #ifdef DIAGNOSTIC 1636 static int busyprt = 0; /* print out busy vnodes */ 1637 SYSCTL_INT(_debug, OID_AUTO, busyprt, CTLFLAG_RW, &busyprt, 0, ""); 1638 #endif 1639 1640 int 1641 vflush(mp, skipvp, flags) 1642 struct mount *mp; 1643 struct vnode *skipvp; 1644 int flags; 1645 { 1646 struct proc *p = curproc; /* XXX */ 1647 struct vnode *vp, *nvp; 1648 int busy = 0; 1649 1650 mtx_lock(&mntvnode_mtx); 1651 loop: 1652 for (vp = LIST_FIRST(&mp->mnt_vnodelist); vp; vp = nvp) { 1653 /* 1654 * Make sure this vnode wasn't reclaimed in getnewvnode(). 1655 * Start over if it has (it won't be on the list anymore). 1656 */ 1657 if (vp->v_mount != mp) 1658 goto loop; 1659 nvp = LIST_NEXT(vp, v_mntvnodes); 1660 /* 1661 * Skip over a selected vnode. 1662 */ 1663 if (vp == skipvp) 1664 continue; 1665 1666 mtx_lock(&vp->v_interlock); 1667 /* 1668 * Skip over a vnodes marked VSYSTEM. 1669 */ 1670 if ((flags & SKIPSYSTEM) && (vp->v_flag & VSYSTEM)) { 1671 mtx_unlock(&vp->v_interlock); 1672 continue; 1673 } 1674 /* 1675 * If WRITECLOSE is set, only flush out regular file vnodes 1676 * open for writing. 1677 */ 1678 if ((flags & WRITECLOSE) && 1679 (vp->v_writecount == 0 || vp->v_type != VREG)) { 1680 mtx_unlock(&vp->v_interlock); 1681 continue; 1682 } 1683 1684 /* 1685 * With v_usecount == 0, all we need to do is clear out the 1686 * vnode data structures and we are done. 1687 */ 1688 if (vp->v_usecount == 0) { 1689 mtx_unlock(&mntvnode_mtx); 1690 vgonel(vp, p); 1691 mtx_lock(&mntvnode_mtx); 1692 continue; 1693 } 1694 1695 /* 1696 * If FORCECLOSE is set, forcibly close the vnode. For block 1697 * or character devices, revert to an anonymous device. For 1698 * all other files, just kill them. 1699 */ 1700 if (flags & FORCECLOSE) { 1701 mtx_unlock(&mntvnode_mtx); 1702 if (vp->v_type != VCHR) { 1703 vgonel(vp, p); 1704 } else { 1705 vclean(vp, 0, p); 1706 vp->v_op = spec_vnodeop_p; 1707 insmntque(vp, (struct mount *) 0); 1708 } 1709 mtx_lock(&mntvnode_mtx); 1710 continue; 1711 } 1712 #ifdef DIAGNOSTIC 1713 if (busyprt) 1714 vprint("vflush: busy vnode", vp); 1715 #endif 1716 mtx_unlock(&vp->v_interlock); 1717 busy++; 1718 } 1719 mtx_unlock(&mntvnode_mtx); 1720 if (busy) 1721 return (EBUSY); 1722 return (0); 1723 } 1724 1725 /* 1726 * Disassociate the underlying file system from a vnode. 1727 */ 1728 static void 1729 vclean(vp, flags, p) 1730 struct vnode *vp; 1731 int flags; 1732 struct proc *p; 1733 { 1734 int active; 1735 1736 /* 1737 * Check to see if the vnode is in use. If so we have to reference it 1738 * before we clean it out so that its count cannot fall to zero and 1739 * generate a race against ourselves to recycle it. 1740 */ 1741 if ((active = vp->v_usecount)) 1742 vp->v_usecount++; 1743 1744 /* 1745 * Prevent the vnode from being recycled or brought into use while we 1746 * clean it out. 1747 */ 1748 if (vp->v_flag & VXLOCK) 1749 panic("vclean: deadlock"); 1750 vp->v_flag |= VXLOCK; 1751 vp->v_vxproc = curproc; 1752 /* 1753 * Even if the count is zero, the VOP_INACTIVE routine may still 1754 * have the object locked while it cleans it out. The VOP_LOCK 1755 * ensures that the VOP_INACTIVE routine is done with its work. 1756 * For active vnodes, it ensures that no other activity can 1757 * occur while the underlying object is being cleaned out. 1758 */ 1759 VOP_LOCK(vp, LK_DRAIN | LK_INTERLOCK, p); 1760 1761 /* 1762 * Clean out any buffers associated with the vnode. 1763 * If the flush fails, just toss the buffers. 1764 */ 1765 if (flags & DOCLOSE) { 1766 if (TAILQ_FIRST(&vp->v_dirtyblkhd) != NULL) 1767 (void) vn_write_suspend_wait(vp, NULL, V_WAIT); 1768 if (vinvalbuf(vp, V_SAVE, NOCRED, p, 0, 0) != 0) 1769 vinvalbuf(vp, 0, NOCRED, p, 0, 0); 1770 } 1771 1772 VOP_DESTROYVOBJECT(vp); 1773 1774 /* 1775 * If purging an active vnode, it must be closed and 1776 * deactivated before being reclaimed. Note that the 1777 * VOP_INACTIVE will unlock the vnode. 1778 */ 1779 if (active) { 1780 if (flags & DOCLOSE) 1781 VOP_CLOSE(vp, FNONBLOCK, NOCRED, p); 1782 VOP_INACTIVE(vp, p); 1783 } else { 1784 /* 1785 * Any other processes trying to obtain this lock must first 1786 * wait for VXLOCK to clear, then call the new lock operation. 1787 */ 1788 VOP_UNLOCK(vp, 0, p); 1789 } 1790 /* 1791 * Reclaim the vnode. 1792 */ 1793 if (VOP_RECLAIM(vp, p)) 1794 panic("vclean: cannot reclaim"); 1795 1796 if (active) { 1797 /* 1798 * Inline copy of vrele() since VOP_INACTIVE 1799 * has already been called. 1800 */ 1801 mtx_lock(&vp->v_interlock); 1802 if (--vp->v_usecount <= 0) { 1803 #ifdef DIAGNOSTIC 1804 if (vp->v_usecount < 0 || vp->v_writecount != 0) { 1805 vprint("vclean: bad ref count", vp); 1806 panic("vclean: ref cnt"); 1807 } 1808 #endif 1809 vfree(vp); 1810 } 1811 mtx_unlock(&vp->v_interlock); 1812 } 1813 1814 cache_purge(vp); 1815 vp->v_vnlock = NULL; 1816 lockdestroy(&vp->v_lock); 1817 1818 if (VSHOULDFREE(vp)) 1819 vfree(vp); 1820 1821 /* 1822 * Done with purge, notify sleepers of the grim news. 1823 */ 1824 vp->v_op = dead_vnodeop_p; 1825 vn_pollgone(vp); 1826 vp->v_tag = VT_NON; 1827 vp->v_flag &= ~VXLOCK; 1828 vp->v_vxproc = NULL; 1829 if (vp->v_flag & VXWANT) { 1830 vp->v_flag &= ~VXWANT; 1831 wakeup((caddr_t) vp); 1832 } 1833 } 1834 1835 /* 1836 * Eliminate all activity associated with the requested vnode 1837 * and with all vnodes aliased to the requested vnode. 1838 */ 1839 int 1840 vop_revoke(ap) 1841 struct vop_revoke_args /* { 1842 struct vnode *a_vp; 1843 int a_flags; 1844 } */ *ap; 1845 { 1846 struct vnode *vp, *vq; 1847 dev_t dev; 1848 1849 KASSERT((ap->a_flags & REVOKEALL) != 0, ("vop_revoke")); 1850 1851 vp = ap->a_vp; 1852 /* 1853 * If a vgone (or vclean) is already in progress, 1854 * wait until it is done and return. 1855 */ 1856 if (vp->v_flag & VXLOCK) { 1857 vp->v_flag |= VXWANT; 1858 msleep((caddr_t)vp, &vp->v_interlock, PINOD | PDROP, 1859 "vop_revokeall", 0); 1860 return (0); 1861 } 1862 dev = vp->v_rdev; 1863 for (;;) { 1864 mtx_lock(&spechash_mtx); 1865 vq = SLIST_FIRST(&dev->si_hlist); 1866 mtx_unlock(&spechash_mtx); 1867 if (!vq) 1868 break; 1869 vgone(vq); 1870 } 1871 return (0); 1872 } 1873 1874 /* 1875 * Recycle an unused vnode to the front of the free list. 1876 * Release the passed interlock if the vnode will be recycled. 1877 */ 1878 int 1879 vrecycle(vp, inter_lkp, p) 1880 struct vnode *vp; 1881 struct mtx *inter_lkp; 1882 struct proc *p; 1883 { 1884 1885 mtx_lock(&vp->v_interlock); 1886 if (vp->v_usecount == 0) { 1887 if (inter_lkp) { 1888 mtx_unlock(inter_lkp); 1889 } 1890 vgonel(vp, p); 1891 return (1); 1892 } 1893 mtx_unlock(&vp->v_interlock); 1894 return (0); 1895 } 1896 1897 /* 1898 * Eliminate all activity associated with a vnode 1899 * in preparation for reuse. 1900 */ 1901 void 1902 vgone(vp) 1903 register struct vnode *vp; 1904 { 1905 struct proc *p = curproc; /* XXX */ 1906 1907 mtx_lock(&vp->v_interlock); 1908 vgonel(vp, p); 1909 } 1910 1911 /* 1912 * vgone, with the vp interlock held. 1913 */ 1914 void 1915 vgonel(vp, p) 1916 struct vnode *vp; 1917 struct proc *p; 1918 { 1919 int s; 1920 1921 /* 1922 * If a vgone (or vclean) is already in progress, 1923 * wait until it is done and return. 1924 */ 1925 if (vp->v_flag & VXLOCK) { 1926 vp->v_flag |= VXWANT; 1927 msleep((caddr_t)vp, &vp->v_interlock, PINOD | PDROP, 1928 "vgone", 0); 1929 return; 1930 } 1931 1932 /* 1933 * Clean out the filesystem specific data. 1934 */ 1935 vclean(vp, DOCLOSE, p); 1936 mtx_lock(&vp->v_interlock); 1937 1938 /* 1939 * Delete from old mount point vnode list, if on one. 1940 */ 1941 if (vp->v_mount != NULL) 1942 insmntque(vp, (struct mount *)0); 1943 /* 1944 * If special device, remove it from special device alias list 1945 * if it is on one. 1946 */ 1947 if (vp->v_type == VCHR && vp->v_rdev != NULL && vp->v_rdev != NODEV) { 1948 mtx_lock(&spechash_mtx); 1949 SLIST_REMOVE(&vp->v_rdev->si_hlist, vp, vnode, v_specnext); 1950 freedev(vp->v_rdev); 1951 mtx_unlock(&spechash_mtx); 1952 vp->v_rdev = NULL; 1953 } 1954 1955 /* 1956 * If it is on the freelist and not already at the head, 1957 * move it to the head of the list. The test of the 1958 * VDOOMED flag and the reference count of zero is because 1959 * it will be removed from the free list by getnewvnode, 1960 * but will not have its reference count incremented until 1961 * after calling vgone. If the reference count were 1962 * incremented first, vgone would (incorrectly) try to 1963 * close the previous instance of the underlying object. 1964 */ 1965 if (vp->v_usecount == 0 && !(vp->v_flag & VDOOMED)) { 1966 s = splbio(); 1967 mtx_lock(&vnode_free_list_mtx); 1968 if (vp->v_flag & VFREE) 1969 TAILQ_REMOVE(&vnode_free_list, vp, v_freelist); 1970 else 1971 freevnodes++; 1972 vp->v_flag |= VFREE; 1973 TAILQ_INSERT_HEAD(&vnode_free_list, vp, v_freelist); 1974 mtx_unlock(&vnode_free_list_mtx); 1975 splx(s); 1976 } 1977 1978 vp->v_type = VBAD; 1979 mtx_unlock(&vp->v_interlock); 1980 } 1981 1982 /* 1983 * Lookup a vnode by device number. 1984 */ 1985 int 1986 vfinddev(dev, type, vpp) 1987 dev_t dev; 1988 enum vtype type; 1989 struct vnode **vpp; 1990 { 1991 struct vnode *vp; 1992 1993 mtx_lock(&spechash_mtx); 1994 SLIST_FOREACH(vp, &dev->si_hlist, v_specnext) { 1995 if (type == vp->v_type) { 1996 *vpp = vp; 1997 mtx_unlock(&spechash_mtx); 1998 return (1); 1999 } 2000 } 2001 mtx_unlock(&spechash_mtx); 2002 return (0); 2003 } 2004 2005 /* 2006 * Calculate the total number of references to a special device. 2007 */ 2008 int 2009 vcount(vp) 2010 struct vnode *vp; 2011 { 2012 struct vnode *vq; 2013 int count; 2014 2015 count = 0; 2016 mtx_lock(&spechash_mtx); 2017 SLIST_FOREACH(vq, &vp->v_rdev->si_hlist, v_specnext) 2018 count += vq->v_usecount; 2019 mtx_unlock(&spechash_mtx); 2020 return (count); 2021 } 2022 2023 /* 2024 * Same as above, but using the dev_t as argument 2025 */ 2026 int 2027 count_dev(dev) 2028 dev_t dev; 2029 { 2030 struct vnode *vp; 2031 2032 vp = SLIST_FIRST(&dev->si_hlist); 2033 if (vp == NULL) 2034 return (0); 2035 return(vcount(vp)); 2036 } 2037 2038 /* 2039 * Print out a description of a vnode. 2040 */ 2041 static char *typename[] = 2042 {"VNON", "VREG", "VDIR", "VBLK", "VCHR", "VLNK", "VSOCK", "VFIFO", "VBAD"}; 2043 2044 void 2045 vprint(label, vp) 2046 char *label; 2047 struct vnode *vp; 2048 { 2049 char buf[96]; 2050 2051 if (label != NULL) 2052 printf("%s: %p: ", label, (void *)vp); 2053 else 2054 printf("%p: ", (void *)vp); 2055 printf("type %s, usecount %d, writecount %d, refcount %d,", 2056 typename[vp->v_type], vp->v_usecount, vp->v_writecount, 2057 vp->v_holdcnt); 2058 buf[0] = '\0'; 2059 if (vp->v_flag & VROOT) 2060 strcat(buf, "|VROOT"); 2061 if (vp->v_flag & VTEXT) 2062 strcat(buf, "|VTEXT"); 2063 if (vp->v_flag & VSYSTEM) 2064 strcat(buf, "|VSYSTEM"); 2065 if (vp->v_flag & VXLOCK) 2066 strcat(buf, "|VXLOCK"); 2067 if (vp->v_flag & VXWANT) 2068 strcat(buf, "|VXWANT"); 2069 if (vp->v_flag & VBWAIT) 2070 strcat(buf, "|VBWAIT"); 2071 if (vp->v_flag & VDOOMED) 2072 strcat(buf, "|VDOOMED"); 2073 if (vp->v_flag & VFREE) 2074 strcat(buf, "|VFREE"); 2075 if (vp->v_flag & VOBJBUF) 2076 strcat(buf, "|VOBJBUF"); 2077 if (buf[0] != '\0') 2078 printf(" flags (%s)", &buf[1]); 2079 if (vp->v_data == NULL) { 2080 printf("\n"); 2081 } else { 2082 printf("\n\t"); 2083 VOP_PRINT(vp); 2084 } 2085 } 2086 2087 #ifdef DDB 2088 #include <ddb/ddb.h> 2089 /* 2090 * List all of the locked vnodes in the system. 2091 * Called when debugging the kernel. 2092 */ 2093 DB_SHOW_COMMAND(lockedvnodes, lockedvnodes) 2094 { 2095 struct proc *p = curproc; /* XXX */ 2096 struct mount *mp, *nmp; 2097 struct vnode *vp; 2098 2099 printf("Locked vnodes\n"); 2100 mtx_lock(&mountlist_mtx); 2101 for (mp = TAILQ_FIRST(&mountlist); mp != NULL; mp = nmp) { 2102 if (vfs_busy(mp, LK_NOWAIT, &mountlist_mtx, p)) { 2103 nmp = TAILQ_NEXT(mp, mnt_list); 2104 continue; 2105 } 2106 LIST_FOREACH(vp, &mp->mnt_vnodelist, v_mntvnodes) { 2107 if (VOP_ISLOCKED(vp, NULL)) 2108 vprint((char *)0, vp); 2109 } 2110 mtx_lock(&mountlist_mtx); 2111 nmp = TAILQ_NEXT(mp, mnt_list); 2112 vfs_unbusy(mp, p); 2113 } 2114 mtx_unlock(&mountlist_mtx); 2115 } 2116 #endif 2117 2118 /* 2119 * Top level filesystem related information gathering. 2120 */ 2121 static int sysctl_ovfs_conf __P((SYSCTL_HANDLER_ARGS)); 2122 2123 static int 2124 vfs_sysctl(SYSCTL_HANDLER_ARGS) 2125 { 2126 int *name = (int *)arg1 - 1; /* XXX */ 2127 u_int namelen = arg2 + 1; /* XXX */ 2128 struct vfsconf *vfsp; 2129 2130 #if 1 || defined(COMPAT_PRELITE2) 2131 /* Resolve ambiguity between VFS_VFSCONF and VFS_GENERIC. */ 2132 if (namelen == 1) 2133 return (sysctl_ovfs_conf(oidp, arg1, arg2, req)); 2134 #endif 2135 2136 /* XXX the below code does not compile; vfs_sysctl does not exist. */ 2137 #ifdef notyet 2138 /* all sysctl names at this level are at least name and field */ 2139 if (namelen < 2) 2140 return (ENOTDIR); /* overloaded */ 2141 if (name[0] != VFS_GENERIC) { 2142 for (vfsp = vfsconf; vfsp; vfsp = vfsp->vfc_next) 2143 if (vfsp->vfc_typenum == name[0]) 2144 break; 2145 if (vfsp == NULL) 2146 return (EOPNOTSUPP); 2147 return ((*vfsp->vfc_vfsops->vfs_sysctl)(&name[1], namelen - 1, 2148 oldp, oldlenp, newp, newlen, p)); 2149 } 2150 #endif 2151 switch (name[1]) { 2152 case VFS_MAXTYPENUM: 2153 if (namelen != 2) 2154 return (ENOTDIR); 2155 return (SYSCTL_OUT(req, &maxvfsconf, sizeof(int))); 2156 case VFS_CONF: 2157 if (namelen != 3) 2158 return (ENOTDIR); /* overloaded */ 2159 for (vfsp = vfsconf; vfsp; vfsp = vfsp->vfc_next) 2160 if (vfsp->vfc_typenum == name[2]) 2161 break; 2162 if (vfsp == NULL) 2163 return (EOPNOTSUPP); 2164 return (SYSCTL_OUT(req, vfsp, sizeof *vfsp)); 2165 } 2166 return (EOPNOTSUPP); 2167 } 2168 2169 SYSCTL_NODE(_vfs, VFS_GENERIC, generic, CTLFLAG_RD, vfs_sysctl, 2170 "Generic filesystem"); 2171 2172 #if 1 || defined(COMPAT_PRELITE2) 2173 2174 static int 2175 sysctl_ovfs_conf(SYSCTL_HANDLER_ARGS) 2176 { 2177 int error; 2178 struct vfsconf *vfsp; 2179 struct ovfsconf ovfs; 2180 2181 for (vfsp = vfsconf; vfsp; vfsp = vfsp->vfc_next) { 2182 ovfs.vfc_vfsops = vfsp->vfc_vfsops; /* XXX used as flag */ 2183 strcpy(ovfs.vfc_name, vfsp->vfc_name); 2184 ovfs.vfc_index = vfsp->vfc_typenum; 2185 ovfs.vfc_refcount = vfsp->vfc_refcount; 2186 ovfs.vfc_flags = vfsp->vfc_flags; 2187 error = SYSCTL_OUT(req, &ovfs, sizeof ovfs); 2188 if (error) 2189 return error; 2190 } 2191 return 0; 2192 } 2193 2194 #endif /* 1 || COMPAT_PRELITE2 */ 2195 2196 #if COMPILING_LINT 2197 #define KINFO_VNODESLOP 10 2198 /* 2199 * Dump vnode list (via sysctl). 2200 * Copyout address of vnode followed by vnode. 2201 */ 2202 /* ARGSUSED */ 2203 static int 2204 sysctl_vnode(SYSCTL_HANDLER_ARGS) 2205 { 2206 struct proc *p = curproc; /* XXX */ 2207 struct mount *mp, *nmp; 2208 struct vnode *nvp, *vp; 2209 int error; 2210 2211 #define VPTRSZ sizeof (struct vnode *) 2212 #define VNODESZ sizeof (struct vnode) 2213 2214 req->lock = 0; 2215 if (!req->oldptr) /* Make an estimate */ 2216 return (SYSCTL_OUT(req, 0, 2217 (numvnodes + KINFO_VNODESLOP) * (VPTRSZ + VNODESZ))); 2218 2219 mtx_lock(&mountlist_mtx); 2220 for (mp = TAILQ_FIRST(&mountlist); mp != NULL; mp = nmp) { 2221 if (vfs_busy(mp, LK_NOWAIT, &mountlist_mtx, p)) { 2222 nmp = TAILQ_NEXT(mp, mnt_list); 2223 continue; 2224 } 2225 again: 2226 mtx_lock(&mntvnode_mtx); 2227 for (vp = LIST_FIRST(&mp->mnt_vnodelist); 2228 vp != NULL; 2229 vp = nvp) { 2230 /* 2231 * Check that the vp is still associated with 2232 * this filesystem. RACE: could have been 2233 * recycled onto the same filesystem. 2234 */ 2235 if (vp->v_mount != mp) { 2236 mtx_unlock(&mntvnode_mtx); 2237 goto again; 2238 } 2239 nvp = LIST_NEXT(vp, v_mntvnodes); 2240 mtx_unlock(&mntvnode_mtx); 2241 if ((error = SYSCTL_OUT(req, &vp, VPTRSZ)) || 2242 (error = SYSCTL_OUT(req, vp, VNODESZ))) 2243 return (error); 2244 mtx_lock(&mntvnode_mtx); 2245 } 2246 mtx_unlock(&mntvnode_mtx); 2247 mtx_lock(&mountlist_mtx); 2248 nmp = TAILQ_NEXT(mp, mnt_list); 2249 vfs_unbusy(mp, p); 2250 } 2251 mtx_unlock(&mountlist_mtx); 2252 2253 return (0); 2254 } 2255 2256 /* 2257 * XXX 2258 * Exporting the vnode list on large systems causes them to crash. 2259 * Exporting the vnode list on medium systems causes sysctl to coredump. 2260 */ 2261 SYSCTL_PROC(_kern, KERN_VNODE, vnode, CTLTYPE_OPAQUE|CTLFLAG_RD, 2262 0, 0, sysctl_vnode, "S,vnode", ""); 2263 #endif 2264 2265 /* 2266 * Check to see if a filesystem is mounted on a block device. 2267 */ 2268 int 2269 vfs_mountedon(vp) 2270 struct vnode *vp; 2271 { 2272 2273 if (vp->v_rdev->si_mountpoint != NULL) 2274 return (EBUSY); 2275 return (0); 2276 } 2277 2278 /* 2279 * Unmount all filesystems. The list is traversed in reverse order 2280 * of mounting to avoid dependencies. 2281 */ 2282 void 2283 vfs_unmountall() 2284 { 2285 struct mount *mp; 2286 struct proc *p; 2287 int error; 2288 2289 if (curproc != NULL) 2290 p = curproc; 2291 else 2292 p = initproc; /* XXX XXX should this be proc0? */ 2293 /* 2294 * Since this only runs when rebooting, it is not interlocked. 2295 */ 2296 while(!TAILQ_EMPTY(&mountlist)) { 2297 mp = TAILQ_LAST(&mountlist, mntlist); 2298 error = dounmount(mp, MNT_FORCE, p); 2299 if (error) { 2300 TAILQ_REMOVE(&mountlist, mp, mnt_list); 2301 printf("unmount of %s failed (", 2302 mp->mnt_stat.f_mntonname); 2303 if (error == EBUSY) 2304 printf("BUSY)\n"); 2305 else 2306 printf("%d)\n", error); 2307 } else { 2308 /* The unmount has removed mp from the mountlist */ 2309 } 2310 } 2311 } 2312 2313 /* 2314 * perform msync on all vnodes under a mount point 2315 * the mount point must be locked. 2316 */ 2317 void 2318 vfs_msync(struct mount *mp, int flags) { 2319 struct vnode *vp, *nvp; 2320 struct vm_object *obj; 2321 int anyio, tries; 2322 2323 tries = 5; 2324 loop: 2325 anyio = 0; 2326 for (vp = LIST_FIRST(&mp->mnt_vnodelist); vp != NULL; vp = nvp) { 2327 2328 nvp = LIST_NEXT(vp, v_mntvnodes); 2329 2330 if (vp->v_mount != mp) { 2331 goto loop; 2332 } 2333 2334 if (vp->v_flag & VXLOCK) /* XXX: what if MNT_WAIT? */ 2335 continue; 2336 2337 if (flags != MNT_WAIT) { 2338 if (VOP_GETVOBJECT(vp, &obj) != 0 || 2339 (obj->flags & OBJ_MIGHTBEDIRTY) == 0) 2340 continue; 2341 if (VOP_ISLOCKED(vp, NULL)) 2342 continue; 2343 } 2344 2345 mtx_lock(&vp->v_interlock); 2346 if (VOP_GETVOBJECT(vp, &obj) == 0 && 2347 (obj->flags & OBJ_MIGHTBEDIRTY)) { 2348 if (!vget(vp, 2349 LK_INTERLOCK | LK_EXCLUSIVE | LK_RETRY | LK_NOOBJ, curproc)) { 2350 if (VOP_GETVOBJECT(vp, &obj) == 0) { 2351 vm_object_page_clean(obj, 0, 0, flags == MNT_WAIT ? OBJPC_SYNC : OBJPC_NOSYNC); 2352 anyio = 1; 2353 } 2354 vput(vp); 2355 } 2356 } else { 2357 mtx_unlock(&vp->v_interlock); 2358 } 2359 } 2360 if (anyio && (--tries > 0)) 2361 goto loop; 2362 } 2363 2364 /* 2365 * Create the VM object needed for VMIO and mmap support. This 2366 * is done for all VREG files in the system. Some filesystems might 2367 * afford the additional metadata buffering capability of the 2368 * VMIO code by making the device node be VMIO mode also. 2369 * 2370 * vp must be locked when vfs_object_create is called. 2371 */ 2372 int 2373 vfs_object_create(vp, p, cred) 2374 struct vnode *vp; 2375 struct proc *p; 2376 struct ucred *cred; 2377 { 2378 return (VOP_CREATEVOBJECT(vp, cred, p)); 2379 } 2380 2381 /* 2382 * Mark a vnode as free, putting it up for recycling. 2383 */ 2384 void 2385 vfree(vp) 2386 struct vnode *vp; 2387 { 2388 int s; 2389 2390 s = splbio(); 2391 mtx_lock(&vnode_free_list_mtx); 2392 KASSERT((vp->v_flag & VFREE) == 0, ("vnode already free")); 2393 if (vp->v_flag & VAGE) { 2394 TAILQ_INSERT_HEAD(&vnode_free_list, vp, v_freelist); 2395 } else { 2396 TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_freelist); 2397 } 2398 freevnodes++; 2399 mtx_unlock(&vnode_free_list_mtx); 2400 vp->v_flag &= ~VAGE; 2401 vp->v_flag |= VFREE; 2402 splx(s); 2403 } 2404 2405 /* 2406 * Opposite of vfree() - mark a vnode as in use. 2407 */ 2408 void 2409 vbusy(vp) 2410 struct vnode *vp; 2411 { 2412 int s; 2413 2414 s = splbio(); 2415 mtx_lock(&vnode_free_list_mtx); 2416 KASSERT((vp->v_flag & VFREE) != 0, ("vnode not free")); 2417 TAILQ_REMOVE(&vnode_free_list, vp, v_freelist); 2418 freevnodes--; 2419 mtx_unlock(&vnode_free_list_mtx); 2420 vp->v_flag &= ~(VFREE|VAGE); 2421 splx(s); 2422 } 2423 2424 /* 2425 * Record a process's interest in events which might happen to 2426 * a vnode. Because poll uses the historic select-style interface 2427 * internally, this routine serves as both the ``check for any 2428 * pending events'' and the ``record my interest in future events'' 2429 * functions. (These are done together, while the lock is held, 2430 * to avoid race conditions.) 2431 */ 2432 int 2433 vn_pollrecord(vp, p, events) 2434 struct vnode *vp; 2435 struct proc *p; 2436 short events; 2437 { 2438 mtx_lock(&vp->v_pollinfo.vpi_lock); 2439 if (vp->v_pollinfo.vpi_revents & events) { 2440 /* 2441 * This leaves events we are not interested 2442 * in available for the other process which 2443 * which presumably had requested them 2444 * (otherwise they would never have been 2445 * recorded). 2446 */ 2447 events &= vp->v_pollinfo.vpi_revents; 2448 vp->v_pollinfo.vpi_revents &= ~events; 2449 2450 mtx_unlock(&vp->v_pollinfo.vpi_lock); 2451 return events; 2452 } 2453 vp->v_pollinfo.vpi_events |= events; 2454 selrecord(p, &vp->v_pollinfo.vpi_selinfo); 2455 mtx_unlock(&vp->v_pollinfo.vpi_lock); 2456 return 0; 2457 } 2458 2459 /* 2460 * Note the occurrence of an event. If the VN_POLLEVENT macro is used, 2461 * it is possible for us to miss an event due to race conditions, but 2462 * that condition is expected to be rare, so for the moment it is the 2463 * preferred interface. 2464 */ 2465 void 2466 vn_pollevent(vp, events) 2467 struct vnode *vp; 2468 short events; 2469 { 2470 mtx_lock(&vp->v_pollinfo.vpi_lock); 2471 if (vp->v_pollinfo.vpi_events & events) { 2472 /* 2473 * We clear vpi_events so that we don't 2474 * call selwakeup() twice if two events are 2475 * posted before the polling process(es) is 2476 * awakened. This also ensures that we take at 2477 * most one selwakeup() if the polling process 2478 * is no longer interested. However, it does 2479 * mean that only one event can be noticed at 2480 * a time. (Perhaps we should only clear those 2481 * event bits which we note?) XXX 2482 */ 2483 vp->v_pollinfo.vpi_events = 0; /* &= ~events ??? */ 2484 vp->v_pollinfo.vpi_revents |= events; 2485 selwakeup(&vp->v_pollinfo.vpi_selinfo); 2486 } 2487 mtx_unlock(&vp->v_pollinfo.vpi_lock); 2488 } 2489 2490 #define VN_KNOTE(vp, b) \ 2491 KNOTE((struct klist *)&vp->v_pollinfo.vpi_selinfo.si_note, (b)) 2492 2493 /* 2494 * Wake up anyone polling on vp because it is being revoked. 2495 * This depends on dead_poll() returning POLLHUP for correct 2496 * behavior. 2497 */ 2498 void 2499 vn_pollgone(vp) 2500 struct vnode *vp; 2501 { 2502 mtx_lock(&vp->v_pollinfo.vpi_lock); 2503 VN_KNOTE(vp, NOTE_REVOKE); 2504 if (vp->v_pollinfo.vpi_events) { 2505 vp->v_pollinfo.vpi_events = 0; 2506 selwakeup(&vp->v_pollinfo.vpi_selinfo); 2507 } 2508 mtx_unlock(&vp->v_pollinfo.vpi_lock); 2509 } 2510 2511 2512 2513 /* 2514 * Routine to create and manage a filesystem syncer vnode. 2515 */ 2516 #define sync_close ((int (*) __P((struct vop_close_args *)))nullop) 2517 static int sync_fsync __P((struct vop_fsync_args *)); 2518 static int sync_inactive __P((struct vop_inactive_args *)); 2519 static int sync_reclaim __P((struct vop_reclaim_args *)); 2520 #define sync_lock ((int (*) __P((struct vop_lock_args *)))vop_nolock) 2521 #define sync_unlock ((int (*) __P((struct vop_unlock_args *)))vop_nounlock) 2522 static int sync_print __P((struct vop_print_args *)); 2523 #define sync_islocked ((int(*) __P((struct vop_islocked_args *)))vop_noislocked) 2524 2525 static vop_t **sync_vnodeop_p; 2526 static struct vnodeopv_entry_desc sync_vnodeop_entries[] = { 2527 { &vop_default_desc, (vop_t *) vop_eopnotsupp }, 2528 { &vop_close_desc, (vop_t *) sync_close }, /* close */ 2529 { &vop_fsync_desc, (vop_t *) sync_fsync }, /* fsync */ 2530 { &vop_inactive_desc, (vop_t *) sync_inactive }, /* inactive */ 2531 { &vop_reclaim_desc, (vop_t *) sync_reclaim }, /* reclaim */ 2532 { &vop_lock_desc, (vop_t *) sync_lock }, /* lock */ 2533 { &vop_unlock_desc, (vop_t *) sync_unlock }, /* unlock */ 2534 { &vop_print_desc, (vop_t *) sync_print }, /* print */ 2535 { &vop_islocked_desc, (vop_t *) sync_islocked }, /* islocked */ 2536 { NULL, NULL } 2537 }; 2538 static struct vnodeopv_desc sync_vnodeop_opv_desc = 2539 { &sync_vnodeop_p, sync_vnodeop_entries }; 2540 2541 VNODEOP_SET(sync_vnodeop_opv_desc); 2542 2543 /* 2544 * Create a new filesystem syncer vnode for the specified mount point. 2545 */ 2546 int 2547 vfs_allocate_syncvnode(mp) 2548 struct mount *mp; 2549 { 2550 struct vnode *vp; 2551 static long start, incr, next; 2552 int error; 2553 2554 /* Allocate a new vnode */ 2555 if ((error = getnewvnode(VT_VFS, mp, sync_vnodeop_p, &vp)) != 0) { 2556 mp->mnt_syncer = NULL; 2557 return (error); 2558 } 2559 vp->v_type = VNON; 2560 /* 2561 * Place the vnode onto the syncer worklist. We attempt to 2562 * scatter them about on the list so that they will go off 2563 * at evenly distributed times even if all the filesystems 2564 * are mounted at once. 2565 */ 2566 next += incr; 2567 if (next == 0 || next > syncer_maxdelay) { 2568 start /= 2; 2569 incr /= 2; 2570 if (start == 0) { 2571 start = syncer_maxdelay / 2; 2572 incr = syncer_maxdelay; 2573 } 2574 next = start; 2575 } 2576 vn_syncer_add_to_worklist(vp, syncdelay > 0 ? next % syncdelay : 0); 2577 mp->mnt_syncer = vp; 2578 return (0); 2579 } 2580 2581 /* 2582 * Do a lazy sync of the filesystem. 2583 */ 2584 static int 2585 sync_fsync(ap) 2586 struct vop_fsync_args /* { 2587 struct vnode *a_vp; 2588 struct ucred *a_cred; 2589 int a_waitfor; 2590 struct proc *a_p; 2591 } */ *ap; 2592 { 2593 struct vnode *syncvp = ap->a_vp; 2594 struct mount *mp = syncvp->v_mount; 2595 struct proc *p = ap->a_p; 2596 int asyncflag; 2597 2598 /* 2599 * We only need to do something if this is a lazy evaluation. 2600 */ 2601 if (ap->a_waitfor != MNT_LAZY) 2602 return (0); 2603 2604 /* 2605 * Move ourselves to the back of the sync list. 2606 */ 2607 vn_syncer_add_to_worklist(syncvp, syncdelay); 2608 2609 /* 2610 * Walk the list of vnodes pushing all that are dirty and 2611 * not already on the sync list. 2612 */ 2613 mtx_lock(&mountlist_mtx); 2614 if (vfs_busy(mp, LK_EXCLUSIVE | LK_NOWAIT, &mountlist_mtx, p) != 0) { 2615 mtx_unlock(&mountlist_mtx); 2616 return (0); 2617 } 2618 if (vn_start_write(NULL, &mp, V_NOWAIT) != 0) { 2619 vfs_unbusy(mp, p); 2620 return (0); 2621 } 2622 asyncflag = mp->mnt_flag & MNT_ASYNC; 2623 mp->mnt_flag &= ~MNT_ASYNC; 2624 vfs_msync(mp, MNT_NOWAIT); 2625 VFS_SYNC(mp, MNT_LAZY, ap->a_cred, p); 2626 if (asyncflag) 2627 mp->mnt_flag |= MNT_ASYNC; 2628 vn_finished_write(mp); 2629 vfs_unbusy(mp, p); 2630 return (0); 2631 } 2632 2633 /* 2634 * The syncer vnode is no referenced. 2635 */ 2636 static int 2637 sync_inactive(ap) 2638 struct vop_inactive_args /* { 2639 struct vnode *a_vp; 2640 struct proc *a_p; 2641 } */ *ap; 2642 { 2643 2644 vgone(ap->a_vp); 2645 return (0); 2646 } 2647 2648 /* 2649 * The syncer vnode is no longer needed and is being decommissioned. 2650 * 2651 * Modifications to the worklist must be protected at splbio(). 2652 */ 2653 static int 2654 sync_reclaim(ap) 2655 struct vop_reclaim_args /* { 2656 struct vnode *a_vp; 2657 } */ *ap; 2658 { 2659 struct vnode *vp = ap->a_vp; 2660 int s; 2661 2662 s = splbio(); 2663 vp->v_mount->mnt_syncer = NULL; 2664 if (vp->v_flag & VONWORKLST) { 2665 LIST_REMOVE(vp, v_synclist); 2666 vp->v_flag &= ~VONWORKLST; 2667 } 2668 splx(s); 2669 2670 return (0); 2671 } 2672 2673 /* 2674 * Print out a syncer vnode. 2675 */ 2676 static int 2677 sync_print(ap) 2678 struct vop_print_args /* { 2679 struct vnode *a_vp; 2680 } */ *ap; 2681 { 2682 struct vnode *vp = ap->a_vp; 2683 2684 printf("syncer vnode"); 2685 if (vp->v_vnlock != NULL) 2686 lockmgr_printinfo(vp->v_vnlock); 2687 printf("\n"); 2688 return (0); 2689 } 2690 2691 /* 2692 * extract the dev_t from a VCHR 2693 */ 2694 dev_t 2695 vn_todev(vp) 2696 struct vnode *vp; 2697 { 2698 if (vp->v_type != VCHR) 2699 return (NODEV); 2700 return (vp->v_rdev); 2701 } 2702 2703 /* 2704 * Check if vnode represents a disk device 2705 */ 2706 int 2707 vn_isdisk(vp, errp) 2708 struct vnode *vp; 2709 int *errp; 2710 { 2711 struct cdevsw *cdevsw; 2712 2713 if (vp->v_type != VCHR) { 2714 if (errp != NULL) 2715 *errp = ENOTBLK; 2716 return (0); 2717 } 2718 if (vp->v_rdev == NULL) { 2719 if (errp != NULL) 2720 *errp = ENXIO; 2721 return (0); 2722 } 2723 cdevsw = devsw(vp->v_rdev); 2724 if (cdevsw == NULL) { 2725 if (errp != NULL) 2726 *errp = ENXIO; 2727 return (0); 2728 } 2729 if (!(cdevsw->d_flags & D_DISK)) { 2730 if (errp != NULL) 2731 *errp = ENOTBLK; 2732 return (0); 2733 } 2734 if (errp != NULL) 2735 *errp = 0; 2736 return (1); 2737 } 2738 2739 /* 2740 * Free data allocated by namei(); see namei(9) for details. 2741 */ 2742 void 2743 NDFREE(ndp, flags) 2744 struct nameidata *ndp; 2745 const uint flags; 2746 { 2747 if (!(flags & NDF_NO_FREE_PNBUF) && 2748 (ndp->ni_cnd.cn_flags & HASBUF)) { 2749 zfree(namei_zone, ndp->ni_cnd.cn_pnbuf); 2750 ndp->ni_cnd.cn_flags &= ~HASBUF; 2751 } 2752 if (!(flags & NDF_NO_DVP_UNLOCK) && 2753 (ndp->ni_cnd.cn_flags & LOCKPARENT) && 2754 ndp->ni_dvp != ndp->ni_vp) 2755 VOP_UNLOCK(ndp->ni_dvp, 0, ndp->ni_cnd.cn_proc); 2756 if (!(flags & NDF_NO_DVP_RELE) && 2757 (ndp->ni_cnd.cn_flags & (LOCKPARENT|WANTPARENT))) { 2758 vrele(ndp->ni_dvp); 2759 ndp->ni_dvp = NULL; 2760 } 2761 if (!(flags & NDF_NO_VP_UNLOCK) && 2762 (ndp->ni_cnd.cn_flags & LOCKLEAF) && ndp->ni_vp) 2763 VOP_UNLOCK(ndp->ni_vp, 0, ndp->ni_cnd.cn_proc); 2764 if (!(flags & NDF_NO_VP_RELE) && 2765 ndp->ni_vp) { 2766 vrele(ndp->ni_vp); 2767 ndp->ni_vp = NULL; 2768 } 2769 if (!(flags & NDF_NO_STARTDIR_RELE) && 2770 (ndp->ni_cnd.cn_flags & SAVESTART)) { 2771 vrele(ndp->ni_startdir); 2772 ndp->ni_startdir = NULL; 2773 } 2774 } 2775 2776 /* 2777 * Common file system object access control check routine. Accepts a 2778 * vnode's type, "mode", uid and gid, requested access mode, credentials, 2779 * and optional call-by-reference privused argument allowing vaccess() 2780 * to indicate to the caller whether privilege was used to satisfy the 2781 * request. Returns 0 on success, or an errno on failure. 2782 */ 2783 int 2784 vaccess(type, file_mode, file_uid, file_gid, acc_mode, cred, privused) 2785 enum vtype type; 2786 mode_t file_mode; 2787 uid_t file_uid; 2788 gid_t file_gid; 2789 mode_t acc_mode; 2790 struct ucred *cred; 2791 int *privused; 2792 { 2793 mode_t dac_granted; 2794 #ifdef CAPABILITIES 2795 mode_t cap_granted; 2796 #endif 2797 2798 /* 2799 * Look for a normal, non-privileged way to access the file/directory 2800 * as requested. If it exists, go with that. 2801 */ 2802 2803 if (privused != NULL) 2804 *privused = 0; 2805 2806 dac_granted = 0; 2807 2808 /* Check the owner. */ 2809 if (cred->cr_uid == file_uid) { 2810 dac_granted |= VADMIN; 2811 if (file_mode & S_IXUSR) 2812 dac_granted |= VEXEC; 2813 if (file_mode & S_IRUSR) 2814 dac_granted |= VREAD; 2815 if (file_mode & S_IWUSR) 2816 dac_granted |= VWRITE; 2817 2818 if ((acc_mode & dac_granted) == acc_mode) 2819 return (0); 2820 2821 goto privcheck; 2822 } 2823 2824 /* Otherwise, check the groups (first match) */ 2825 if (groupmember(file_gid, cred)) { 2826 if (file_mode & S_IXGRP) 2827 dac_granted |= VEXEC; 2828 if (file_mode & S_IRGRP) 2829 dac_granted |= VREAD; 2830 if (file_mode & S_IWGRP) 2831 dac_granted |= VWRITE; 2832 2833 if ((acc_mode & dac_granted) == acc_mode) 2834 return (0); 2835 2836 goto privcheck; 2837 } 2838 2839 /* Otherwise, check everyone else. */ 2840 if (file_mode & S_IXOTH) 2841 dac_granted |= VEXEC; 2842 if (file_mode & S_IROTH) 2843 dac_granted |= VREAD; 2844 if (file_mode & S_IWOTH) 2845 dac_granted |= VWRITE; 2846 if ((acc_mode & dac_granted) == acc_mode) 2847 return (0); 2848 2849 privcheck: 2850 if (!suser_xxx(cred, NULL, PRISON_ROOT)) { 2851 /* XXX audit: privilege used */ 2852 if (privused != NULL) 2853 *privused = 1; 2854 return (0); 2855 } 2856 2857 #ifdef CAPABILITIES 2858 /* 2859 * Build a capability mask to determine if the set of capabilities 2860 * satisfies the requirements when combined with the granted mask 2861 * from above. 2862 * For each capability, if the capability is required, bitwise 2863 * or the request type onto the cap_granted mask. 2864 */ 2865 cap_granted = 0; 2866 if ((acc_mode & VEXEC) && ((dac_granted & VEXEC) == 0) && 2867 !cap_check_xxx(cred, NULL, CAP_DAC_EXECUTE, PRISON_ROOT)) 2868 cap_granted |= VEXEC; 2869 2870 if ((acc_mode & VREAD) && ((dac_granted & VREAD) == 0) && 2871 !cap_check_xxx(cred, NULL, CAP_DAC_READ_SEARCH, PRISON_ROOT)) 2872 cap_granted |= VREAD; 2873 2874 if ((acc_mode & VWRITE) && ((dac_granted & VWRITE) == 0) && 2875 !cap_check_xxx(cred, NULL, CAP_DAC_WRITE, PRISON_ROOT)) 2876 cap_granted |= VWRITE; 2877 2878 if ((acc_mode & VADMIN) && ((dac_granted & VADMIN) == 0) && 2879 !cap_check_xxx(cred, NULL, CAP_FOWNER, PRISON_ROOT)) 2880 cap_granted |= VADMIN; 2881 2882 if ((acc_mode & (cap_granted | dac_granted)) == acc_mode) { 2883 /* XXX audit: privilege used */ 2884 if (privused != NULL) 2885 *privused = 1; 2886 return (0); 2887 } 2888 #endif 2889 2890 return ((acc_mode & VADMIN) ? EPERM : EACCES); 2891 } 2892 2893