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 * 4. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * @(#)vfs_subr.c 8.31 (Berkeley) 5/26/95 35 */ 36 37 /* 38 * External virtual filesystem routines 39 */ 40 41 #include <sys/cdefs.h> 42 __FBSDID("$FreeBSD$"); 43 44 #include "opt_ddb.h" 45 #include "opt_mac.h" 46 47 #include <sys/param.h> 48 #include <sys/systm.h> 49 #include <sys/bio.h> 50 #include <sys/buf.h> 51 #include <sys/conf.h> 52 #include <sys/dirent.h> 53 #include <sys/event.h> 54 #include <sys/eventhandler.h> 55 #include <sys/extattr.h> 56 #include <sys/file.h> 57 #include <sys/fcntl.h> 58 #include <sys/jail.h> 59 #include <sys/kdb.h> 60 #include <sys/kernel.h> 61 #include <sys/kthread.h> 62 #include <sys/lockf.h> 63 #include <sys/malloc.h> 64 #include <sys/mount.h> 65 #include <sys/namei.h> 66 #include <sys/priv.h> 67 #include <sys/reboot.h> 68 #include <sys/sleepqueue.h> 69 #include <sys/stat.h> 70 #include <sys/sysctl.h> 71 #include <sys/syslog.h> 72 #include <sys/vmmeter.h> 73 #include <sys/vnode.h> 74 75 #include <machine/stdarg.h> 76 77 #include <security/mac/mac_framework.h> 78 79 #include <vm/vm.h> 80 #include <vm/vm_object.h> 81 #include <vm/vm_extern.h> 82 #include <vm/pmap.h> 83 #include <vm/vm_map.h> 84 #include <vm/vm_page.h> 85 #include <vm/vm_kern.h> 86 #include <vm/uma.h> 87 88 #ifdef DDB 89 #include <ddb/ddb.h> 90 #endif 91 92 #define WI_MPSAFEQ 0 93 #define WI_GIANTQ 1 94 95 static MALLOC_DEFINE(M_NETADDR, "subr_export_host", "Export host address structure"); 96 97 static void delmntque(struct vnode *vp); 98 static int flushbuflist(struct bufv *bufv, int flags, struct bufobj *bo, 99 int slpflag, int slptimeo); 100 static void syncer_shutdown(void *arg, int howto); 101 static int vtryrecycle(struct vnode *vp); 102 static void vbusy(struct vnode *vp); 103 static void vinactive(struct vnode *, struct thread *); 104 static void v_incr_usecount(struct vnode *); 105 static void v_decr_usecount(struct vnode *); 106 static void v_decr_useonly(struct vnode *); 107 static void v_upgrade_usecount(struct vnode *); 108 static void vfree(struct vnode *); 109 static void vnlru_free(int); 110 static void vdestroy(struct vnode *); 111 static void vgonel(struct vnode *); 112 static void vfs_knllock(void *arg); 113 static void vfs_knlunlock(void *arg); 114 static int vfs_knllocked(void *arg); 115 116 117 /* 118 * Enable Giant pushdown based on whether or not the vm is mpsafe in this 119 * build. Without mpsafevm the buffer cache can not run Giant free. 120 */ 121 int mpsafe_vfs = 1; 122 TUNABLE_INT("debug.mpsafevfs", &mpsafe_vfs); 123 SYSCTL_INT(_debug, OID_AUTO, mpsafevfs, CTLFLAG_RD, &mpsafe_vfs, 0, 124 "MPSAFE VFS"); 125 126 /* 127 * Number of vnodes in existence. Increased whenever getnewvnode() 128 * allocates a new vnode, decreased on vdestroy() called on VI_DOOMed 129 * vnode. 130 */ 131 static unsigned long numvnodes; 132 133 SYSCTL_LONG(_vfs, OID_AUTO, numvnodes, CTLFLAG_RD, &numvnodes, 0, ""); 134 135 /* 136 * Conversion tables for conversion from vnode types to inode formats 137 * and back. 138 */ 139 enum vtype iftovt_tab[16] = { 140 VNON, VFIFO, VCHR, VNON, VDIR, VNON, VBLK, VNON, 141 VREG, VNON, VLNK, VNON, VSOCK, VNON, VNON, VBAD, 142 }; 143 int vttoif_tab[10] = { 144 0, S_IFREG, S_IFDIR, S_IFBLK, S_IFCHR, S_IFLNK, 145 S_IFSOCK, S_IFIFO, S_IFMT, S_IFMT 146 }; 147 148 /* 149 * List of vnodes that are ready for recycling. 150 */ 151 static TAILQ_HEAD(freelst, vnode) vnode_free_list; 152 153 /* 154 * Free vnode target. Free vnodes may simply be files which have been stat'd 155 * but not read. This is somewhat common, and a small cache of such files 156 * should be kept to avoid recreation costs. 157 */ 158 static u_long wantfreevnodes; 159 SYSCTL_LONG(_vfs, OID_AUTO, wantfreevnodes, CTLFLAG_RW, &wantfreevnodes, 0, ""); 160 /* Number of vnodes in the free list. */ 161 static u_long freevnodes; 162 SYSCTL_LONG(_vfs, OID_AUTO, freevnodes, CTLFLAG_RD, &freevnodes, 0, ""); 163 164 /* 165 * Various variables used for debugging the new implementation of 166 * reassignbuf(). 167 * XXX these are probably of (very) limited utility now. 168 */ 169 static int reassignbufcalls; 170 SYSCTL_INT(_vfs, OID_AUTO, reassignbufcalls, CTLFLAG_RW, &reassignbufcalls, 0, ""); 171 172 /* 173 * Cache for the mount type id assigned to NFS. This is used for 174 * special checks in nfs/nfs_nqlease.c and vm/vnode_pager.c. 175 */ 176 int nfs_mount_type = -1; 177 178 /* To keep more than one thread at a time from running vfs_getnewfsid */ 179 static struct mtx mntid_mtx; 180 181 /* 182 * Lock for any access to the following: 183 * vnode_free_list 184 * numvnodes 185 * freevnodes 186 */ 187 static struct mtx vnode_free_list_mtx; 188 189 /* Publicly exported FS */ 190 struct nfs_public nfs_pub; 191 192 /* Zone for allocation of new vnodes - used exclusively by getnewvnode() */ 193 static uma_zone_t vnode_zone; 194 static uma_zone_t vnodepoll_zone; 195 196 /* Set to 1 to print out reclaim of active vnodes */ 197 int prtactive; 198 199 /* 200 * The workitem queue. 201 * 202 * It is useful to delay writes of file data and filesystem metadata 203 * for tens of seconds so that quickly created and deleted files need 204 * not waste disk bandwidth being created and removed. To realize this, 205 * we append vnodes to a "workitem" queue. When running with a soft 206 * updates implementation, most pending metadata dependencies should 207 * not wait for more than a few seconds. Thus, mounted on block devices 208 * are delayed only about a half the time that file data is delayed. 209 * Similarly, directory updates are more critical, so are only delayed 210 * about a third the time that file data is delayed. Thus, there are 211 * SYNCER_MAXDELAY queues that are processed round-robin at a rate of 212 * one each second (driven off the filesystem syncer process). The 213 * syncer_delayno variable indicates the next queue that is to be processed. 214 * Items that need to be processed soon are placed in this queue: 215 * 216 * syncer_workitem_pending[syncer_delayno] 217 * 218 * A delay of fifteen seconds is done by placing the request fifteen 219 * entries later in the queue: 220 * 221 * syncer_workitem_pending[(syncer_delayno + 15) & syncer_mask] 222 * 223 */ 224 static int syncer_delayno; 225 static long syncer_mask; 226 LIST_HEAD(synclist, bufobj); 227 static struct synclist *syncer_workitem_pending[2]; 228 /* 229 * The sync_mtx protects: 230 * bo->bo_synclist 231 * sync_vnode_count 232 * syncer_delayno 233 * syncer_state 234 * syncer_workitem_pending 235 * syncer_worklist_len 236 * rushjob 237 */ 238 static struct mtx sync_mtx; 239 240 #define SYNCER_MAXDELAY 32 241 static int syncer_maxdelay = SYNCER_MAXDELAY; /* maximum delay time */ 242 static int syncdelay = 30; /* max time to delay syncing data */ 243 static int filedelay = 30; /* time to delay syncing files */ 244 SYSCTL_INT(_kern, OID_AUTO, filedelay, CTLFLAG_RW, &filedelay, 0, ""); 245 static int dirdelay = 29; /* time to delay syncing directories */ 246 SYSCTL_INT(_kern, OID_AUTO, dirdelay, CTLFLAG_RW, &dirdelay, 0, ""); 247 static int metadelay = 28; /* time to delay syncing metadata */ 248 SYSCTL_INT(_kern, OID_AUTO, metadelay, CTLFLAG_RW, &metadelay, 0, ""); 249 static int rushjob; /* number of slots to run ASAP */ 250 static int stat_rush_requests; /* number of times I/O speeded up */ 251 SYSCTL_INT(_debug, OID_AUTO, rush_requests, CTLFLAG_RW, &stat_rush_requests, 0, ""); 252 253 /* 254 * When shutting down the syncer, run it at four times normal speed. 255 */ 256 #define SYNCER_SHUTDOWN_SPEEDUP 4 257 static int sync_vnode_count; 258 static int syncer_worklist_len; 259 static enum { SYNCER_RUNNING, SYNCER_SHUTTING_DOWN, SYNCER_FINAL_DELAY } 260 syncer_state; 261 262 /* 263 * Number of vnodes we want to exist at any one time. This is mostly used 264 * to size hash tables in vnode-related code. It is normally not used in 265 * getnewvnode(), as wantfreevnodes is normally nonzero.) 266 * 267 * XXX desiredvnodes is historical cruft and should not exist. 268 */ 269 int desiredvnodes; 270 SYSCTL_INT(_kern, KERN_MAXVNODES, maxvnodes, CTLFLAG_RW, 271 &desiredvnodes, 0, "Maximum number of vnodes"); 272 SYSCTL_INT(_kern, OID_AUTO, minvnodes, CTLFLAG_RW, 273 &wantfreevnodes, 0, "Minimum number of vnodes (legacy)"); 274 static int vnlru_nowhere; 275 SYSCTL_INT(_debug, OID_AUTO, vnlru_nowhere, CTLFLAG_RW, 276 &vnlru_nowhere, 0, "Number of times the vnlru process ran without success"); 277 278 /* 279 * Macros to control when a vnode is freed and recycled. All require 280 * the vnode interlock. 281 */ 282 #define VCANRECYCLE(vp) (((vp)->v_iflag & VI_FREE) && !(vp)->v_holdcnt) 283 #define VSHOULDFREE(vp) (!((vp)->v_iflag & VI_FREE) && !(vp)->v_holdcnt) 284 #define VSHOULDBUSY(vp) (((vp)->v_iflag & VI_FREE) && (vp)->v_holdcnt) 285 286 287 /* 288 * Initialize the vnode management data structures. 289 */ 290 #ifndef MAXVNODES_MAX 291 #define MAXVNODES_MAX 100000 292 #endif 293 static void 294 vntblinit(void *dummy __unused) 295 { 296 297 /* 298 * Desiredvnodes is a function of the physical memory size and 299 * the kernel's heap size. Specifically, desiredvnodes scales 300 * in proportion to the physical memory size until two fifths 301 * of the kernel's heap size is consumed by vnodes and vm 302 * objects. 303 */ 304 desiredvnodes = min(maxproc + cnt.v_page_count / 4, 2 * vm_kmem_size / 305 (5 * (sizeof(struct vm_object) + sizeof(struct vnode)))); 306 if (desiredvnodes > MAXVNODES_MAX) { 307 if (bootverbose) 308 printf("Reducing kern.maxvnodes %d -> %d\n", 309 desiredvnodes, MAXVNODES_MAX); 310 desiredvnodes = MAXVNODES_MAX; 311 } 312 wantfreevnodes = desiredvnodes / 4; 313 mtx_init(&mntid_mtx, "mntid", NULL, MTX_DEF); 314 TAILQ_INIT(&vnode_free_list); 315 mtx_init(&vnode_free_list_mtx, "vnode_free_list", NULL, MTX_DEF); 316 vnode_zone = uma_zcreate("VNODE", sizeof (struct vnode), NULL, NULL, 317 NULL, NULL, UMA_ALIGN_PTR, 0); 318 vnodepoll_zone = uma_zcreate("VNODEPOLL", sizeof (struct vpollinfo), 319 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); 320 /* 321 * Initialize the filesystem syncer. 322 */ 323 syncer_workitem_pending[WI_MPSAFEQ] = hashinit(syncer_maxdelay, M_VNODE, 324 &syncer_mask); 325 syncer_workitem_pending[WI_GIANTQ] = hashinit(syncer_maxdelay, M_VNODE, 326 &syncer_mask); 327 syncer_maxdelay = syncer_mask + 1; 328 mtx_init(&sync_mtx, "Syncer mtx", NULL, MTX_DEF); 329 } 330 SYSINIT(vfs, SI_SUB_VFS, SI_ORDER_FIRST, vntblinit, NULL); 331 332 333 /* 334 * Mark a mount point as busy. Used to synchronize access and to delay 335 * unmounting. Interlock is not released on failure. 336 */ 337 int 338 vfs_busy(struct mount *mp, int flags, struct mtx *interlkp, 339 struct thread *td) 340 { 341 int lkflags; 342 343 MNT_ILOCK(mp); 344 MNT_REF(mp); 345 if (mp->mnt_kern_flag & MNTK_UNMOUNT) { 346 if (flags & LK_NOWAIT) { 347 MNT_REL(mp); 348 MNT_IUNLOCK(mp); 349 return (ENOENT); 350 } 351 if (interlkp) 352 mtx_unlock(interlkp); 353 mp->mnt_kern_flag |= MNTK_MWAIT; 354 /* 355 * Since all busy locks are shared except the exclusive 356 * lock granted when unmounting, the only place that a 357 * wakeup needs to be done is at the release of the 358 * exclusive lock at the end of dounmount. 359 */ 360 msleep(mp, MNT_MTX(mp), PVFS, "vfs_busy", 0); 361 MNT_REL(mp); 362 MNT_IUNLOCK(mp); 363 if (interlkp) 364 mtx_lock(interlkp); 365 return (ENOENT); 366 } 367 if (interlkp) 368 mtx_unlock(interlkp); 369 lkflags = LK_SHARED | LK_INTERLOCK; 370 if (lockmgr(&mp->mnt_lock, lkflags, MNT_MTX(mp))) 371 panic("vfs_busy: unexpected lock failure"); 372 return (0); 373 } 374 375 /* 376 * Free a busy filesystem. 377 */ 378 void 379 vfs_unbusy(struct mount *mp, struct thread *td) 380 { 381 382 lockmgr(&mp->mnt_lock, LK_RELEASE, NULL); 383 vfs_rel(mp); 384 } 385 386 /* 387 * Lookup a mount point by filesystem identifier. 388 */ 389 struct mount * 390 vfs_getvfs(fsid_t *fsid) 391 { 392 struct mount *mp; 393 394 mtx_lock(&mountlist_mtx); 395 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 396 if (mp->mnt_stat.f_fsid.val[0] == fsid->val[0] && 397 mp->mnt_stat.f_fsid.val[1] == fsid->val[1]) { 398 vfs_ref(mp); 399 mtx_unlock(&mountlist_mtx); 400 return (mp); 401 } 402 } 403 mtx_unlock(&mountlist_mtx); 404 return ((struct mount *) 0); 405 } 406 407 /* 408 * Check if a user can access privileged mount options. 409 */ 410 int 411 vfs_suser(struct mount *mp, struct thread *td) 412 { 413 int error; 414 415 /* 416 * If the thread is jailed, but this is not a jail-friendly file 417 * system, deny immediately. 418 */ 419 if (jailed(td->td_ucred) && !(mp->mnt_vfc->vfc_flags & VFCF_JAIL)) 420 return (EPERM); 421 422 /* 423 * If the file system was mounted outside a jail and a jailed thread 424 * tries to access it, deny immediately. 425 */ 426 if (!jailed(mp->mnt_cred) && jailed(td->td_ucred)) 427 return (EPERM); 428 429 /* 430 * If the file system was mounted inside different jail that the jail of 431 * the calling thread, deny immediately. 432 */ 433 if (jailed(mp->mnt_cred) && jailed(td->td_ucred) && 434 mp->mnt_cred->cr_prison != td->td_ucred->cr_prison) { 435 return (EPERM); 436 } 437 438 if ((mp->mnt_flag & MNT_USER) == 0 || 439 mp->mnt_cred->cr_uid != td->td_ucred->cr_uid) { 440 if ((error = priv_check(td, PRIV_VFS_MOUNT_OWNER)) != 0) 441 return (error); 442 } 443 return (0); 444 } 445 446 /* 447 * Get a new unique fsid. Try to make its val[0] unique, since this value 448 * will be used to create fake device numbers for stat(). Also try (but 449 * not so hard) make its val[0] unique mod 2^16, since some emulators only 450 * support 16-bit device numbers. We end up with unique val[0]'s for the 451 * first 2^16 calls and unique val[0]'s mod 2^16 for the first 2^8 calls. 452 * 453 * Keep in mind that several mounts may be running in parallel. Starting 454 * the search one past where the previous search terminated is both a 455 * micro-optimization and a defense against returning the same fsid to 456 * different mounts. 457 */ 458 void 459 vfs_getnewfsid(struct mount *mp) 460 { 461 static u_int16_t mntid_base; 462 struct mount *nmp; 463 fsid_t tfsid; 464 int mtype; 465 466 mtx_lock(&mntid_mtx); 467 mtype = mp->mnt_vfc->vfc_typenum; 468 tfsid.val[1] = mtype; 469 mtype = (mtype & 0xFF) << 24; 470 for (;;) { 471 tfsid.val[0] = makedev(255, 472 mtype | ((mntid_base & 0xFF00) << 8) | (mntid_base & 0xFF)); 473 mntid_base++; 474 if ((nmp = vfs_getvfs(&tfsid)) == NULL) 475 break; 476 vfs_rel(nmp); 477 } 478 mp->mnt_stat.f_fsid.val[0] = tfsid.val[0]; 479 mp->mnt_stat.f_fsid.val[1] = tfsid.val[1]; 480 mtx_unlock(&mntid_mtx); 481 } 482 483 /* 484 * Knob to control the precision of file timestamps: 485 * 486 * 0 = seconds only; nanoseconds zeroed. 487 * 1 = seconds and nanoseconds, accurate within 1/HZ. 488 * 2 = seconds and nanoseconds, truncated to microseconds. 489 * >=3 = seconds and nanoseconds, maximum precision. 490 */ 491 enum { TSP_SEC, TSP_HZ, TSP_USEC, TSP_NSEC }; 492 493 static int timestamp_precision = TSP_SEC; 494 SYSCTL_INT(_vfs, OID_AUTO, timestamp_precision, CTLFLAG_RW, 495 ×tamp_precision, 0, ""); 496 497 /* 498 * Get a current timestamp. 499 */ 500 void 501 vfs_timestamp(struct timespec *tsp) 502 { 503 struct timeval tv; 504 505 switch (timestamp_precision) { 506 case TSP_SEC: 507 tsp->tv_sec = time_second; 508 tsp->tv_nsec = 0; 509 break; 510 case TSP_HZ: 511 getnanotime(tsp); 512 break; 513 case TSP_USEC: 514 microtime(&tv); 515 TIMEVAL_TO_TIMESPEC(&tv, tsp); 516 break; 517 case TSP_NSEC: 518 default: 519 nanotime(tsp); 520 break; 521 } 522 } 523 524 /* 525 * Set vnode attributes to VNOVAL 526 */ 527 void 528 vattr_null(struct vattr *vap) 529 { 530 531 vap->va_type = VNON; 532 vap->va_size = VNOVAL; 533 vap->va_bytes = VNOVAL; 534 vap->va_mode = VNOVAL; 535 vap->va_nlink = VNOVAL; 536 vap->va_uid = VNOVAL; 537 vap->va_gid = VNOVAL; 538 vap->va_fsid = VNOVAL; 539 vap->va_fileid = VNOVAL; 540 vap->va_blocksize = VNOVAL; 541 vap->va_rdev = VNOVAL; 542 vap->va_atime.tv_sec = VNOVAL; 543 vap->va_atime.tv_nsec = VNOVAL; 544 vap->va_mtime.tv_sec = VNOVAL; 545 vap->va_mtime.tv_nsec = VNOVAL; 546 vap->va_ctime.tv_sec = VNOVAL; 547 vap->va_ctime.tv_nsec = VNOVAL; 548 vap->va_birthtime.tv_sec = VNOVAL; 549 vap->va_birthtime.tv_nsec = VNOVAL; 550 vap->va_flags = VNOVAL; 551 vap->va_gen = VNOVAL; 552 vap->va_vaflags = 0; 553 } 554 555 /* 556 * This routine is called when we have too many vnodes. It attempts 557 * to free <count> vnodes and will potentially free vnodes that still 558 * have VM backing store (VM backing store is typically the cause 559 * of a vnode blowout so we want to do this). Therefore, this operation 560 * is not considered cheap. 561 * 562 * A number of conditions may prevent a vnode from being reclaimed. 563 * the buffer cache may have references on the vnode, a directory 564 * vnode may still have references due to the namei cache representing 565 * underlying files, or the vnode may be in active use. It is not 566 * desireable to reuse such vnodes. These conditions may cause the 567 * number of vnodes to reach some minimum value regardless of what 568 * you set kern.maxvnodes to. Do not set kern.maxvnodes too low. 569 */ 570 static int 571 vlrureclaim(struct mount *mp) 572 { 573 struct thread *td; 574 struct vnode *vp; 575 int done; 576 int trigger; 577 int usevnodes; 578 int count; 579 580 /* 581 * Calculate the trigger point, don't allow user 582 * screwups to blow us up. This prevents us from 583 * recycling vnodes with lots of resident pages. We 584 * aren't trying to free memory, we are trying to 585 * free vnodes. 586 */ 587 usevnodes = desiredvnodes; 588 if (usevnodes <= 0) 589 usevnodes = 1; 590 trigger = cnt.v_page_count * 2 / usevnodes; 591 done = 0; 592 td = curthread; 593 vn_start_write(NULL, &mp, V_WAIT); 594 MNT_ILOCK(mp); 595 count = mp->mnt_nvnodelistsize / 10 + 1; 596 while (count != 0) { 597 vp = TAILQ_FIRST(&mp->mnt_nvnodelist); 598 while (vp != NULL && vp->v_type == VMARKER) 599 vp = TAILQ_NEXT(vp, v_nmntvnodes); 600 if (vp == NULL) 601 break; 602 TAILQ_REMOVE(&mp->mnt_nvnodelist, vp, v_nmntvnodes); 603 TAILQ_INSERT_TAIL(&mp->mnt_nvnodelist, vp, v_nmntvnodes); 604 --count; 605 if (!VI_TRYLOCK(vp)) 606 goto next_iter; 607 /* 608 * If it's been deconstructed already, it's still 609 * referenced, or it exceeds the trigger, skip it. 610 */ 611 if (vp->v_usecount || !LIST_EMPTY(&(vp)->v_cache_src) || 612 (vp->v_iflag & VI_DOOMED) != 0 || (vp->v_object != NULL && 613 vp->v_object->resident_page_count > trigger)) { 614 VI_UNLOCK(vp); 615 goto next_iter; 616 } 617 MNT_IUNLOCK(mp); 618 vholdl(vp); 619 if (VOP_LOCK(vp, LK_INTERLOCK|LK_EXCLUSIVE|LK_NOWAIT)) { 620 vdrop(vp); 621 goto next_iter_mntunlocked; 622 } 623 VI_LOCK(vp); 624 /* 625 * v_usecount may have been bumped after VOP_LOCK() dropped 626 * the vnode interlock and before it was locked again. 627 * 628 * It is not necessary to recheck VI_DOOMED because it can 629 * only be set by another thread that holds both the vnode 630 * lock and vnode interlock. If another thread has the 631 * vnode lock before we get to VOP_LOCK() and obtains the 632 * vnode interlock after VOP_LOCK() drops the vnode 633 * interlock, the other thread will be unable to drop the 634 * vnode lock before our VOP_LOCK() call fails. 635 */ 636 if (vp->v_usecount || !LIST_EMPTY(&(vp)->v_cache_src) || 637 (vp->v_object != NULL && 638 vp->v_object->resident_page_count > trigger)) { 639 VOP_UNLOCK(vp, LK_INTERLOCK); 640 goto next_iter_mntunlocked; 641 } 642 KASSERT((vp->v_iflag & VI_DOOMED) == 0, 643 ("VI_DOOMED unexpectedly detected in vlrureclaim()")); 644 vgonel(vp); 645 VOP_UNLOCK(vp, 0); 646 vdropl(vp); 647 done++; 648 next_iter_mntunlocked: 649 if ((count % 256) != 0) 650 goto relock_mnt; 651 goto yield; 652 next_iter: 653 if ((count % 256) != 0) 654 continue; 655 MNT_IUNLOCK(mp); 656 yield: 657 uio_yield(); 658 relock_mnt: 659 MNT_ILOCK(mp); 660 } 661 MNT_IUNLOCK(mp); 662 vn_finished_write(mp); 663 return done; 664 } 665 666 /* 667 * Attempt to keep the free list at wantfreevnodes length. 668 */ 669 static void 670 vnlru_free(int count) 671 { 672 struct vnode *vp; 673 int vfslocked; 674 675 mtx_assert(&vnode_free_list_mtx, MA_OWNED); 676 for (; count > 0; count--) { 677 vp = TAILQ_FIRST(&vnode_free_list); 678 /* 679 * The list can be modified while the free_list_mtx 680 * has been dropped and vp could be NULL here. 681 */ 682 if (!vp) 683 break; 684 VNASSERT(vp->v_op != NULL, vp, 685 ("vnlru_free: vnode already reclaimed.")); 686 TAILQ_REMOVE(&vnode_free_list, vp, v_freelist); 687 /* 688 * Don't recycle if we can't get the interlock. 689 */ 690 if (!VI_TRYLOCK(vp)) { 691 TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_freelist); 692 continue; 693 } 694 VNASSERT(VCANRECYCLE(vp), vp, 695 ("vp inconsistent on freelist")); 696 freevnodes--; 697 vp->v_iflag &= ~VI_FREE; 698 vholdl(vp); 699 mtx_unlock(&vnode_free_list_mtx); 700 VI_UNLOCK(vp); 701 vfslocked = VFS_LOCK_GIANT(vp->v_mount); 702 vtryrecycle(vp); 703 VFS_UNLOCK_GIANT(vfslocked); 704 /* 705 * If the recycled succeeded this vdrop will actually free 706 * the vnode. If not it will simply place it back on 707 * the free list. 708 */ 709 vdrop(vp); 710 mtx_lock(&vnode_free_list_mtx); 711 } 712 } 713 /* 714 * Attempt to recycle vnodes in a context that is always safe to block. 715 * Calling vlrurecycle() from the bowels of filesystem code has some 716 * interesting deadlock problems. 717 */ 718 static struct proc *vnlruproc; 719 static int vnlruproc_sig; 720 721 static void 722 vnlru_proc(void) 723 { 724 struct mount *mp, *nmp; 725 int done; 726 struct proc *p = vnlruproc; 727 struct thread *td = curthread; 728 729 EVENTHANDLER_REGISTER(shutdown_pre_sync, kproc_shutdown, p, 730 SHUTDOWN_PRI_FIRST); 731 732 mtx_lock(&Giant); 733 734 for (;;) { 735 kproc_suspend_check(p); 736 mtx_lock(&vnode_free_list_mtx); 737 if (freevnodes > wantfreevnodes) 738 vnlru_free(freevnodes - wantfreevnodes); 739 if (numvnodes <= desiredvnodes * 9 / 10) { 740 vnlruproc_sig = 0; 741 wakeup(&vnlruproc_sig); 742 msleep(vnlruproc, &vnode_free_list_mtx, 743 PVFS|PDROP, "vlruwt", hz); 744 continue; 745 } 746 mtx_unlock(&vnode_free_list_mtx); 747 done = 0; 748 mtx_lock(&mountlist_mtx); 749 for (mp = TAILQ_FIRST(&mountlist); mp != NULL; mp = nmp) { 750 int vfsunlocked; 751 if (vfs_busy(mp, LK_NOWAIT, &mountlist_mtx, td)) { 752 nmp = TAILQ_NEXT(mp, mnt_list); 753 continue; 754 } 755 if (!VFS_NEEDSGIANT(mp)) { 756 mtx_unlock(&Giant); 757 vfsunlocked = 1; 758 } else 759 vfsunlocked = 0; 760 done += vlrureclaim(mp); 761 if (vfsunlocked) 762 mtx_lock(&Giant); 763 mtx_lock(&mountlist_mtx); 764 nmp = TAILQ_NEXT(mp, mnt_list); 765 vfs_unbusy(mp, td); 766 } 767 mtx_unlock(&mountlist_mtx); 768 if (done == 0) { 769 EVENTHANDLER_INVOKE(vfs_lowvnodes, desiredvnodes / 10); 770 #if 0 771 /* These messages are temporary debugging aids */ 772 if (vnlru_nowhere < 5) 773 printf("vnlru process getting nowhere..\n"); 774 else if (vnlru_nowhere == 5) 775 printf("vnlru process messages stopped.\n"); 776 #endif 777 vnlru_nowhere++; 778 tsleep(vnlruproc, PPAUSE, "vlrup", hz * 3); 779 } else 780 uio_yield(); 781 } 782 } 783 784 static struct kproc_desc vnlru_kp = { 785 "vnlru", 786 vnlru_proc, 787 &vnlruproc 788 }; 789 SYSINIT(vnlru, SI_SUB_KTHREAD_UPDATE, SI_ORDER_FIRST, kproc_start, 790 &vnlru_kp); 791 792 /* 793 * Routines having to do with the management of the vnode table. 794 */ 795 796 static void 797 vdestroy(struct vnode *vp) 798 { 799 struct bufobj *bo; 800 801 CTR1(KTR_VFS, "vdestroy vp %p", vp); 802 mtx_lock(&vnode_free_list_mtx); 803 numvnodes--; 804 mtx_unlock(&vnode_free_list_mtx); 805 bo = &vp->v_bufobj; 806 VNASSERT((vp->v_iflag & VI_FREE) == 0, vp, 807 ("cleaned vnode still on the free list.")); 808 VNASSERT(vp->v_data == NULL, vp, ("cleaned vnode isn't")); 809 VNASSERT(vp->v_holdcnt == 0, vp, ("Non-zero hold count")); 810 VNASSERT(vp->v_usecount == 0, vp, ("Non-zero use count")); 811 VNASSERT(vp->v_writecount == 0, vp, ("Non-zero write count")); 812 VNASSERT(bo->bo_numoutput == 0, vp, ("Clean vnode has pending I/O's")); 813 VNASSERT(bo->bo_clean.bv_cnt == 0, vp, ("cleanbufcnt not 0")); 814 VNASSERT(bo->bo_clean.bv_root == NULL, vp, ("cleanblkroot not NULL")); 815 VNASSERT(bo->bo_dirty.bv_cnt == 0, vp, ("dirtybufcnt not 0")); 816 VNASSERT(bo->bo_dirty.bv_root == NULL, vp, ("dirtyblkroot not NULL")); 817 VNASSERT(TAILQ_EMPTY(&vp->v_cache_dst), vp, ("vp has namecache dst")); 818 VNASSERT(LIST_EMPTY(&vp->v_cache_src), vp, ("vp has namecache src")); 819 VI_UNLOCK(vp); 820 #ifdef MAC 821 mac_vnode_destroy(vp); 822 #endif 823 if (vp->v_pollinfo != NULL) { 824 knlist_destroy(&vp->v_pollinfo->vpi_selinfo.si_note); 825 mtx_destroy(&vp->v_pollinfo->vpi_lock); 826 uma_zfree(vnodepoll_zone, vp->v_pollinfo); 827 } 828 #ifdef INVARIANTS 829 /* XXX Elsewhere we can detect an already freed vnode via NULL v_op. */ 830 vp->v_op = NULL; 831 #endif 832 lockdestroy(vp->v_vnlock); 833 mtx_destroy(&vp->v_interlock); 834 mtx_destroy(BO_MTX(bo)); 835 uma_zfree(vnode_zone, vp); 836 } 837 838 /* 839 * Try to recycle a freed vnode. We abort if anyone picks up a reference 840 * before we actually vgone(). This function must be called with the vnode 841 * held to prevent the vnode from being returned to the free list midway 842 * through vgone(). 843 */ 844 static int 845 vtryrecycle(struct vnode *vp) 846 { 847 struct mount *vnmp; 848 849 CTR1(KTR_VFS, "vtryrecycle: trying vp %p", vp); 850 VNASSERT(vp->v_holdcnt, vp, 851 ("vtryrecycle: Recycling vp %p without a reference.", vp)); 852 /* 853 * This vnode may found and locked via some other list, if so we 854 * can't recycle it yet. 855 */ 856 if (VOP_LOCK(vp, LK_EXCLUSIVE | LK_NOWAIT) != 0) 857 return (EWOULDBLOCK); 858 /* 859 * Don't recycle if its filesystem is being suspended. 860 */ 861 if (vn_start_write(vp, &vnmp, V_NOWAIT) != 0) { 862 VOP_UNLOCK(vp, 0); 863 return (EBUSY); 864 } 865 /* 866 * If we got this far, we need to acquire the interlock and see if 867 * anyone picked up this vnode from another list. If not, we will 868 * mark it with DOOMED via vgonel() so that anyone who does find it 869 * will skip over it. 870 */ 871 VI_LOCK(vp); 872 if (vp->v_usecount) { 873 VOP_UNLOCK(vp, LK_INTERLOCK); 874 vn_finished_write(vnmp); 875 return (EBUSY); 876 } 877 if ((vp->v_iflag & VI_DOOMED) == 0) 878 vgonel(vp); 879 VOP_UNLOCK(vp, LK_INTERLOCK); 880 vn_finished_write(vnmp); 881 CTR1(KTR_VFS, "vtryrecycle: recycled vp %p", vp); 882 return (0); 883 } 884 885 /* 886 * Return the next vnode from the free list. 887 */ 888 int 889 getnewvnode(const char *tag, struct mount *mp, struct vop_vector *vops, 890 struct vnode **vpp) 891 { 892 struct vnode *vp = NULL; 893 struct bufobj *bo; 894 895 mtx_lock(&vnode_free_list_mtx); 896 /* 897 * Lend our context to reclaim vnodes if they've exceeded the max. 898 */ 899 if (freevnodes > wantfreevnodes) 900 vnlru_free(1); 901 /* 902 * Wait for available vnodes. 903 */ 904 if (numvnodes > desiredvnodes) { 905 if (mp != NULL && (mp->mnt_kern_flag & MNTK_SUSPEND)) { 906 /* 907 * File system is beeing suspended, we cannot risk a 908 * deadlock here, so allocate new vnode anyway. 909 */ 910 if (freevnodes > wantfreevnodes) 911 vnlru_free(freevnodes - wantfreevnodes); 912 goto alloc; 913 } 914 if (vnlruproc_sig == 0) { 915 vnlruproc_sig = 1; /* avoid unnecessary wakeups */ 916 wakeup(vnlruproc); 917 } 918 msleep(&vnlruproc_sig, &vnode_free_list_mtx, PVFS, 919 "vlruwk", hz); 920 #if 0 /* XXX Not all VFS_VGET/ffs_vget callers check returns. */ 921 if (numvnodes > desiredvnodes) { 922 mtx_unlock(&vnode_free_list_mtx); 923 return (ENFILE); 924 } 925 #endif 926 } 927 alloc: 928 numvnodes++; 929 mtx_unlock(&vnode_free_list_mtx); 930 vp = (struct vnode *) uma_zalloc(vnode_zone, M_WAITOK|M_ZERO); 931 /* 932 * Setup locks. 933 */ 934 vp->v_vnlock = &vp->v_lock; 935 mtx_init(&vp->v_interlock, "vnode interlock", NULL, MTX_DEF); 936 /* 937 * By default, don't allow shared locks unless filesystems 938 * opt-in. 939 */ 940 lockinit(vp->v_vnlock, PVFS, tag, VLKTIMEOUT, LK_NOSHARE); 941 /* 942 * Initialize bufobj. 943 */ 944 bo = &vp->v_bufobj; 945 bo->__bo_vnode = vp; 946 mtx_init(BO_MTX(bo), "bufobj interlock", NULL, MTX_DEF); 947 bo->bo_ops = &buf_ops_bio; 948 bo->bo_private = vp; 949 TAILQ_INIT(&bo->bo_clean.bv_hd); 950 TAILQ_INIT(&bo->bo_dirty.bv_hd); 951 /* 952 * Initialize namecache. 953 */ 954 LIST_INIT(&vp->v_cache_src); 955 TAILQ_INIT(&vp->v_cache_dst); 956 /* 957 * Finalize various vnode identity bits. 958 */ 959 vp->v_type = VNON; 960 vp->v_tag = tag; 961 vp->v_op = vops; 962 v_incr_usecount(vp); 963 vp->v_data = 0; 964 #ifdef MAC 965 mac_vnode_init(vp); 966 if (mp != NULL && (mp->mnt_flag & MNT_MULTILABEL) == 0) 967 mac_vnode_associate_singlelabel(mp, vp); 968 else if (mp == NULL) 969 printf("NULL mp in getnewvnode()\n"); 970 #endif 971 if (mp != NULL) { 972 bo->bo_bsize = mp->mnt_stat.f_iosize; 973 if ((mp->mnt_kern_flag & MNTK_NOKNOTE) != 0) 974 vp->v_vflag |= VV_NOKNOTE; 975 } 976 977 CTR2(KTR_VFS, "getnewvnode: mp %p vp %p", mp, vp); 978 *vpp = vp; 979 return (0); 980 } 981 982 /* 983 * Delete from old mount point vnode list, if on one. 984 */ 985 static void 986 delmntque(struct vnode *vp) 987 { 988 struct mount *mp; 989 990 mp = vp->v_mount; 991 if (mp == NULL) 992 return; 993 MNT_ILOCK(mp); 994 vp->v_mount = NULL; 995 VNASSERT(mp->mnt_nvnodelistsize > 0, vp, 996 ("bad mount point vnode list size")); 997 TAILQ_REMOVE(&mp->mnt_nvnodelist, vp, v_nmntvnodes); 998 mp->mnt_nvnodelistsize--; 999 MNT_REL(mp); 1000 MNT_IUNLOCK(mp); 1001 } 1002 1003 static void 1004 insmntque_stddtr(struct vnode *vp, void *dtr_arg) 1005 { 1006 1007 vp->v_data = NULL; 1008 vp->v_op = &dead_vnodeops; 1009 /* XXX non mp-safe fs may still call insmntque with vnode 1010 unlocked */ 1011 if (!VOP_ISLOCKED(vp)) 1012 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 1013 vgone(vp); 1014 vput(vp); 1015 } 1016 1017 /* 1018 * Insert into list of vnodes for the new mount point, if available. 1019 */ 1020 int 1021 insmntque1(struct vnode *vp, struct mount *mp, 1022 void (*dtr)(struct vnode *, void *), void *dtr_arg) 1023 { 1024 1025 KASSERT(vp->v_mount == NULL, 1026 ("insmntque: vnode already on per mount vnode list")); 1027 VNASSERT(mp != NULL, vp, ("Don't call insmntque(foo, NULL)")); 1028 MNT_ILOCK(mp); 1029 if ((mp->mnt_kern_flag & MNTK_NOINSMNTQ) != 0 && 1030 mp->mnt_nvnodelistsize == 0) { 1031 MNT_IUNLOCK(mp); 1032 if (dtr != NULL) 1033 dtr(vp, dtr_arg); 1034 return (EBUSY); 1035 } 1036 vp->v_mount = mp; 1037 MNT_REF(mp); 1038 TAILQ_INSERT_TAIL(&mp->mnt_nvnodelist, vp, v_nmntvnodes); 1039 VNASSERT(mp->mnt_nvnodelistsize >= 0, vp, 1040 ("neg mount point vnode list size")); 1041 mp->mnt_nvnodelistsize++; 1042 MNT_IUNLOCK(mp); 1043 return (0); 1044 } 1045 1046 int 1047 insmntque(struct vnode *vp, struct mount *mp) 1048 { 1049 1050 return (insmntque1(vp, mp, insmntque_stddtr, NULL)); 1051 } 1052 1053 /* 1054 * Flush out and invalidate all buffers associated with a bufobj 1055 * Called with the underlying object locked. 1056 */ 1057 int 1058 bufobj_invalbuf(struct bufobj *bo, int flags, struct thread *td, int slpflag, 1059 int slptimeo) 1060 { 1061 int error; 1062 1063 BO_LOCK(bo); 1064 if (flags & V_SAVE) { 1065 error = bufobj_wwait(bo, slpflag, slptimeo); 1066 if (error) { 1067 BO_UNLOCK(bo); 1068 return (error); 1069 } 1070 if (bo->bo_dirty.bv_cnt > 0) { 1071 BO_UNLOCK(bo); 1072 if ((error = BO_SYNC(bo, MNT_WAIT, td)) != 0) 1073 return (error); 1074 /* 1075 * XXX We could save a lock/unlock if this was only 1076 * enabled under INVARIANTS 1077 */ 1078 BO_LOCK(bo); 1079 if (bo->bo_numoutput > 0 || bo->bo_dirty.bv_cnt > 0) 1080 panic("vinvalbuf: dirty bufs"); 1081 } 1082 } 1083 /* 1084 * If you alter this loop please notice that interlock is dropped and 1085 * reacquired in flushbuflist. Special care is needed to ensure that 1086 * no race conditions occur from this. 1087 */ 1088 do { 1089 error = flushbuflist(&bo->bo_clean, 1090 flags, bo, slpflag, slptimeo); 1091 if (error == 0) 1092 error = flushbuflist(&bo->bo_dirty, 1093 flags, bo, slpflag, slptimeo); 1094 if (error != 0 && error != EAGAIN) { 1095 BO_UNLOCK(bo); 1096 return (error); 1097 } 1098 } while (error != 0); 1099 1100 /* 1101 * Wait for I/O to complete. XXX needs cleaning up. The vnode can 1102 * have write I/O in-progress but if there is a VM object then the 1103 * VM object can also have read-I/O in-progress. 1104 */ 1105 do { 1106 bufobj_wwait(bo, 0, 0); 1107 BO_UNLOCK(bo); 1108 if (bo->bo_object != NULL) { 1109 VM_OBJECT_LOCK(bo->bo_object); 1110 vm_object_pip_wait(bo->bo_object, "bovlbx"); 1111 VM_OBJECT_UNLOCK(bo->bo_object); 1112 } 1113 BO_LOCK(bo); 1114 } while (bo->bo_numoutput > 0); 1115 BO_UNLOCK(bo); 1116 1117 /* 1118 * Destroy the copy in the VM cache, too. 1119 */ 1120 if (bo->bo_object != NULL) { 1121 VM_OBJECT_LOCK(bo->bo_object); 1122 vm_object_page_remove(bo->bo_object, 0, 0, 1123 (flags & V_SAVE) ? TRUE : FALSE); 1124 VM_OBJECT_UNLOCK(bo->bo_object); 1125 } 1126 1127 #ifdef INVARIANTS 1128 BO_LOCK(bo); 1129 if ((flags & (V_ALT | V_NORMAL)) == 0 && 1130 (bo->bo_dirty.bv_cnt > 0 || bo->bo_clean.bv_cnt > 0)) 1131 panic("vinvalbuf: flush failed"); 1132 BO_UNLOCK(bo); 1133 #endif 1134 return (0); 1135 } 1136 1137 /* 1138 * Flush out and invalidate all buffers associated with a vnode. 1139 * Called with the underlying object locked. 1140 */ 1141 int 1142 vinvalbuf(struct vnode *vp, int flags, struct thread *td, int slpflag, 1143 int slptimeo) 1144 { 1145 1146 CTR2(KTR_VFS, "vinvalbuf vp %p flags %d", vp, flags); 1147 ASSERT_VOP_LOCKED(vp, "vinvalbuf"); 1148 return (bufobj_invalbuf(&vp->v_bufobj, flags, td, slpflag, slptimeo)); 1149 } 1150 1151 /* 1152 * Flush out buffers on the specified list. 1153 * 1154 */ 1155 static int 1156 flushbuflist( struct bufv *bufv, int flags, struct bufobj *bo, int slpflag, 1157 int slptimeo) 1158 { 1159 struct buf *bp, *nbp; 1160 int retval, error; 1161 daddr_t lblkno; 1162 b_xflags_t xflags; 1163 1164 ASSERT_BO_LOCKED(bo); 1165 1166 retval = 0; 1167 TAILQ_FOREACH_SAFE(bp, &bufv->bv_hd, b_bobufs, nbp) { 1168 if (((flags & V_NORMAL) && (bp->b_xflags & BX_ALTDATA)) || 1169 ((flags & V_ALT) && (bp->b_xflags & BX_ALTDATA) == 0)) { 1170 continue; 1171 } 1172 lblkno = 0; 1173 xflags = 0; 1174 if (nbp != NULL) { 1175 lblkno = nbp->b_lblkno; 1176 xflags = nbp->b_xflags & 1177 (BX_BKGRDMARKER | BX_VNDIRTY | BX_VNCLEAN); 1178 } 1179 retval = EAGAIN; 1180 error = BUF_TIMELOCK(bp, 1181 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, BO_MTX(bo), 1182 "flushbuf", slpflag, slptimeo); 1183 if (error) { 1184 BO_LOCK(bo); 1185 return (error != ENOLCK ? error : EAGAIN); 1186 } 1187 KASSERT(bp->b_bufobj == bo, 1188 ("bp %p wrong b_bufobj %p should be %p", 1189 bp, bp->b_bufobj, bo)); 1190 if (bp->b_bufobj != bo) { /* XXX: necessary ? */ 1191 BUF_UNLOCK(bp); 1192 BO_LOCK(bo); 1193 return (EAGAIN); 1194 } 1195 /* 1196 * XXX Since there are no node locks for NFS, I 1197 * believe there is a slight chance that a delayed 1198 * write will occur while sleeping just above, so 1199 * check for it. 1200 */ 1201 if (((bp->b_flags & (B_DELWRI | B_INVAL)) == B_DELWRI) && 1202 (flags & V_SAVE)) { 1203 bremfree(bp); 1204 bp->b_flags |= B_ASYNC; 1205 bwrite(bp); 1206 BO_LOCK(bo); 1207 return (EAGAIN); /* XXX: why not loop ? */ 1208 } 1209 bremfree(bp); 1210 bp->b_flags |= (B_INVAL | B_RELBUF); 1211 bp->b_flags &= ~B_ASYNC; 1212 brelse(bp); 1213 BO_LOCK(bo); 1214 if (nbp != NULL && 1215 (nbp->b_bufobj != bo || 1216 nbp->b_lblkno != lblkno || 1217 (nbp->b_xflags & 1218 (BX_BKGRDMARKER | BX_VNDIRTY | BX_VNCLEAN)) != xflags)) 1219 break; /* nbp invalid */ 1220 } 1221 return (retval); 1222 } 1223 1224 /* 1225 * Truncate a file's buffer and pages to a specified length. This 1226 * is in lieu of the old vinvalbuf mechanism, which performed unneeded 1227 * sync activity. 1228 */ 1229 int 1230 vtruncbuf(struct vnode *vp, struct ucred *cred, struct thread *td, 1231 off_t length, int blksize) 1232 { 1233 struct buf *bp, *nbp; 1234 int anyfreed; 1235 int trunclbn; 1236 struct bufobj *bo; 1237 1238 CTR2(KTR_VFS, "vtruncbuf vp %p length %jd", vp, length); 1239 /* 1240 * Round up to the *next* lbn. 1241 */ 1242 trunclbn = (length + blksize - 1) / blksize; 1243 1244 ASSERT_VOP_LOCKED(vp, "vtruncbuf"); 1245 restart: 1246 bo = &vp->v_bufobj; 1247 BO_LOCK(bo); 1248 anyfreed = 1; 1249 for (;anyfreed;) { 1250 anyfreed = 0; 1251 TAILQ_FOREACH_SAFE(bp, &bo->bo_clean.bv_hd, b_bobufs, nbp) { 1252 if (bp->b_lblkno < trunclbn) 1253 continue; 1254 if (BUF_LOCK(bp, 1255 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, 1256 BO_MTX(bo)) == ENOLCK) 1257 goto restart; 1258 1259 bremfree(bp); 1260 bp->b_flags |= (B_INVAL | B_RELBUF); 1261 bp->b_flags &= ~B_ASYNC; 1262 brelse(bp); 1263 anyfreed = 1; 1264 1265 if (nbp != NULL && 1266 (((nbp->b_xflags & BX_VNCLEAN) == 0) || 1267 (nbp->b_vp != vp) || 1268 (nbp->b_flags & B_DELWRI))) { 1269 goto restart; 1270 } 1271 BO_LOCK(bo); 1272 } 1273 1274 TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) { 1275 if (bp->b_lblkno < trunclbn) 1276 continue; 1277 if (BUF_LOCK(bp, 1278 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, 1279 BO_MTX(bo)) == ENOLCK) 1280 goto restart; 1281 bremfree(bp); 1282 bp->b_flags |= (B_INVAL | B_RELBUF); 1283 bp->b_flags &= ~B_ASYNC; 1284 brelse(bp); 1285 anyfreed = 1; 1286 if (nbp != NULL && 1287 (((nbp->b_xflags & BX_VNDIRTY) == 0) || 1288 (nbp->b_vp != vp) || 1289 (nbp->b_flags & B_DELWRI) == 0)) { 1290 goto restart; 1291 } 1292 BO_LOCK(bo); 1293 } 1294 } 1295 1296 if (length > 0) { 1297 restartsync: 1298 TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) { 1299 if (bp->b_lblkno > 0) 1300 continue; 1301 /* 1302 * Since we hold the vnode lock this should only 1303 * fail if we're racing with the buf daemon. 1304 */ 1305 if (BUF_LOCK(bp, 1306 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, 1307 BO_MTX(bo)) == ENOLCK) { 1308 goto restart; 1309 } 1310 VNASSERT((bp->b_flags & B_DELWRI), vp, 1311 ("buf(%p) on dirty queue without DELWRI", bp)); 1312 1313 bremfree(bp); 1314 bawrite(bp); 1315 BO_LOCK(bo); 1316 goto restartsync; 1317 } 1318 } 1319 1320 bufobj_wwait(bo, 0, 0); 1321 BO_UNLOCK(bo); 1322 vnode_pager_setsize(vp, length); 1323 1324 return (0); 1325 } 1326 1327 /* 1328 * buf_splay() - splay tree core for the clean/dirty list of buffers in 1329 * a vnode. 1330 * 1331 * NOTE: We have to deal with the special case of a background bitmap 1332 * buffer, a situation where two buffers will have the same logical 1333 * block offset. We want (1) only the foreground buffer to be accessed 1334 * in a lookup and (2) must differentiate between the foreground and 1335 * background buffer in the splay tree algorithm because the splay 1336 * tree cannot normally handle multiple entities with the same 'index'. 1337 * We accomplish this by adding differentiating flags to the splay tree's 1338 * numerical domain. 1339 */ 1340 static 1341 struct buf * 1342 buf_splay(daddr_t lblkno, b_xflags_t xflags, struct buf *root) 1343 { 1344 struct buf dummy; 1345 struct buf *lefttreemax, *righttreemin, *y; 1346 1347 if (root == NULL) 1348 return (NULL); 1349 lefttreemax = righttreemin = &dummy; 1350 for (;;) { 1351 if (lblkno < root->b_lblkno || 1352 (lblkno == root->b_lblkno && 1353 (xflags & BX_BKGRDMARKER) < (root->b_xflags & BX_BKGRDMARKER))) { 1354 if ((y = root->b_left) == NULL) 1355 break; 1356 if (lblkno < y->b_lblkno) { 1357 /* Rotate right. */ 1358 root->b_left = y->b_right; 1359 y->b_right = root; 1360 root = y; 1361 if ((y = root->b_left) == NULL) 1362 break; 1363 } 1364 /* Link into the new root's right tree. */ 1365 righttreemin->b_left = root; 1366 righttreemin = root; 1367 } else if (lblkno > root->b_lblkno || 1368 (lblkno == root->b_lblkno && 1369 (xflags & BX_BKGRDMARKER) > (root->b_xflags & BX_BKGRDMARKER))) { 1370 if ((y = root->b_right) == NULL) 1371 break; 1372 if (lblkno > y->b_lblkno) { 1373 /* Rotate left. */ 1374 root->b_right = y->b_left; 1375 y->b_left = root; 1376 root = y; 1377 if ((y = root->b_right) == NULL) 1378 break; 1379 } 1380 /* Link into the new root's left tree. */ 1381 lefttreemax->b_right = root; 1382 lefttreemax = root; 1383 } else { 1384 break; 1385 } 1386 root = y; 1387 } 1388 /* Assemble the new root. */ 1389 lefttreemax->b_right = root->b_left; 1390 righttreemin->b_left = root->b_right; 1391 root->b_left = dummy.b_right; 1392 root->b_right = dummy.b_left; 1393 return (root); 1394 } 1395 1396 static void 1397 buf_vlist_remove(struct buf *bp) 1398 { 1399 struct buf *root; 1400 struct bufv *bv; 1401 1402 KASSERT(bp->b_bufobj != NULL, ("No b_bufobj %p", bp)); 1403 ASSERT_BO_LOCKED(bp->b_bufobj); 1404 KASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) != 1405 (BX_VNDIRTY|BX_VNCLEAN), 1406 ("buf_vlist_remove: Buf %p is on two lists", bp)); 1407 if (bp->b_xflags & BX_VNDIRTY) 1408 bv = &bp->b_bufobj->bo_dirty; 1409 else 1410 bv = &bp->b_bufobj->bo_clean; 1411 if (bp != bv->bv_root) { 1412 root = buf_splay(bp->b_lblkno, bp->b_xflags, bv->bv_root); 1413 KASSERT(root == bp, ("splay lookup failed in remove")); 1414 } 1415 if (bp->b_left == NULL) { 1416 root = bp->b_right; 1417 } else { 1418 root = buf_splay(bp->b_lblkno, bp->b_xflags, bp->b_left); 1419 root->b_right = bp->b_right; 1420 } 1421 bv->bv_root = root; 1422 TAILQ_REMOVE(&bv->bv_hd, bp, b_bobufs); 1423 bv->bv_cnt--; 1424 bp->b_xflags &= ~(BX_VNDIRTY | BX_VNCLEAN); 1425 } 1426 1427 /* 1428 * Add the buffer to the sorted clean or dirty block list using a 1429 * splay tree algorithm. 1430 * 1431 * NOTE: xflags is passed as a constant, optimizing this inline function! 1432 */ 1433 static void 1434 buf_vlist_add(struct buf *bp, struct bufobj *bo, b_xflags_t xflags) 1435 { 1436 struct buf *root; 1437 struct bufv *bv; 1438 1439 ASSERT_BO_LOCKED(bo); 1440 KASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) == 0, 1441 ("buf_vlist_add: Buf %p has existing xflags %d", bp, bp->b_xflags)); 1442 bp->b_xflags |= xflags; 1443 if (xflags & BX_VNDIRTY) 1444 bv = &bo->bo_dirty; 1445 else 1446 bv = &bo->bo_clean; 1447 1448 root = buf_splay(bp->b_lblkno, bp->b_xflags, bv->bv_root); 1449 if (root == NULL) { 1450 bp->b_left = NULL; 1451 bp->b_right = NULL; 1452 TAILQ_INSERT_TAIL(&bv->bv_hd, bp, b_bobufs); 1453 } else if (bp->b_lblkno < root->b_lblkno || 1454 (bp->b_lblkno == root->b_lblkno && 1455 (bp->b_xflags & BX_BKGRDMARKER) < (root->b_xflags & BX_BKGRDMARKER))) { 1456 bp->b_left = root->b_left; 1457 bp->b_right = root; 1458 root->b_left = NULL; 1459 TAILQ_INSERT_BEFORE(root, bp, b_bobufs); 1460 } else { 1461 bp->b_right = root->b_right; 1462 bp->b_left = root; 1463 root->b_right = NULL; 1464 TAILQ_INSERT_AFTER(&bv->bv_hd, root, bp, b_bobufs); 1465 } 1466 bv->bv_cnt++; 1467 bv->bv_root = bp; 1468 } 1469 1470 /* 1471 * Lookup a buffer using the splay tree. Note that we specifically avoid 1472 * shadow buffers used in background bitmap writes. 1473 * 1474 * This code isn't quite efficient as it could be because we are maintaining 1475 * two sorted lists and do not know which list the block resides in. 1476 * 1477 * During a "make buildworld" the desired buffer is found at one of 1478 * the roots more than 60% of the time. Thus, checking both roots 1479 * before performing either splay eliminates unnecessary splays on the 1480 * first tree splayed. 1481 */ 1482 struct buf * 1483 gbincore(struct bufobj *bo, daddr_t lblkno) 1484 { 1485 struct buf *bp; 1486 1487 ASSERT_BO_LOCKED(bo); 1488 if ((bp = bo->bo_clean.bv_root) != NULL && 1489 bp->b_lblkno == lblkno && !(bp->b_xflags & BX_BKGRDMARKER)) 1490 return (bp); 1491 if ((bp = bo->bo_dirty.bv_root) != NULL && 1492 bp->b_lblkno == lblkno && !(bp->b_xflags & BX_BKGRDMARKER)) 1493 return (bp); 1494 if ((bp = bo->bo_clean.bv_root) != NULL) { 1495 bo->bo_clean.bv_root = bp = buf_splay(lblkno, 0, bp); 1496 if (bp->b_lblkno == lblkno && !(bp->b_xflags & BX_BKGRDMARKER)) 1497 return (bp); 1498 } 1499 if ((bp = bo->bo_dirty.bv_root) != NULL) { 1500 bo->bo_dirty.bv_root = bp = buf_splay(lblkno, 0, bp); 1501 if (bp->b_lblkno == lblkno && !(bp->b_xflags & BX_BKGRDMARKER)) 1502 return (bp); 1503 } 1504 return (NULL); 1505 } 1506 1507 /* 1508 * Associate a buffer with a vnode. 1509 */ 1510 void 1511 bgetvp(struct vnode *vp, struct buf *bp) 1512 { 1513 struct bufobj *bo; 1514 1515 bo = &vp->v_bufobj; 1516 ASSERT_BO_LOCKED(bo); 1517 VNASSERT(bp->b_vp == NULL, bp->b_vp, ("bgetvp: not free")); 1518 1519 CTR3(KTR_BUF, "bgetvp(%p) vp %p flags %X", bp, vp, bp->b_flags); 1520 VNASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) == 0, vp, 1521 ("bgetvp: bp already attached! %p", bp)); 1522 1523 vhold(vp); 1524 if (VFS_NEEDSGIANT(vp->v_mount) || bo->bo_flag & BO_NEEDSGIANT) 1525 bp->b_flags |= B_NEEDSGIANT; 1526 bp->b_vp = vp; 1527 bp->b_bufobj = bo; 1528 /* 1529 * Insert onto list for new vnode. 1530 */ 1531 buf_vlist_add(bp, bo, BX_VNCLEAN); 1532 } 1533 1534 /* 1535 * Disassociate a buffer from a vnode. 1536 */ 1537 void 1538 brelvp(struct buf *bp) 1539 { 1540 struct bufobj *bo; 1541 struct vnode *vp; 1542 1543 CTR3(KTR_BUF, "brelvp(%p) vp %p flags %X", bp, bp->b_vp, bp->b_flags); 1544 KASSERT(bp->b_vp != NULL, ("brelvp: NULL")); 1545 1546 /* 1547 * Delete from old vnode list, if on one. 1548 */ 1549 vp = bp->b_vp; /* XXX */ 1550 bo = bp->b_bufobj; 1551 BO_LOCK(bo); 1552 if (bp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN)) 1553 buf_vlist_remove(bp); 1554 else 1555 panic("brelvp: Buffer %p not on queue.", bp); 1556 if ((bo->bo_flag & BO_ONWORKLST) && bo->bo_dirty.bv_cnt == 0) { 1557 bo->bo_flag &= ~BO_ONWORKLST; 1558 mtx_lock(&sync_mtx); 1559 LIST_REMOVE(bo, bo_synclist); 1560 syncer_worklist_len--; 1561 mtx_unlock(&sync_mtx); 1562 } 1563 bp->b_flags &= ~B_NEEDSGIANT; 1564 bp->b_vp = NULL; 1565 bp->b_bufobj = NULL; 1566 BO_UNLOCK(bo); 1567 vdrop(vp); 1568 } 1569 1570 /* 1571 * Add an item to the syncer work queue. 1572 */ 1573 static void 1574 vn_syncer_add_to_worklist(struct bufobj *bo, int delay) 1575 { 1576 int queue, slot; 1577 1578 ASSERT_BO_LOCKED(bo); 1579 1580 mtx_lock(&sync_mtx); 1581 if (bo->bo_flag & BO_ONWORKLST) 1582 LIST_REMOVE(bo, bo_synclist); 1583 else { 1584 bo->bo_flag |= BO_ONWORKLST; 1585 syncer_worklist_len++; 1586 } 1587 1588 if (delay > syncer_maxdelay - 2) 1589 delay = syncer_maxdelay - 2; 1590 slot = (syncer_delayno + delay) & syncer_mask; 1591 1592 queue = VFS_NEEDSGIANT(bo->__bo_vnode->v_mount) ? WI_GIANTQ : 1593 WI_MPSAFEQ; 1594 LIST_INSERT_HEAD(&syncer_workitem_pending[queue][slot], bo, 1595 bo_synclist); 1596 mtx_unlock(&sync_mtx); 1597 } 1598 1599 static int 1600 sysctl_vfs_worklist_len(SYSCTL_HANDLER_ARGS) 1601 { 1602 int error, len; 1603 1604 mtx_lock(&sync_mtx); 1605 len = syncer_worklist_len - sync_vnode_count; 1606 mtx_unlock(&sync_mtx); 1607 error = SYSCTL_OUT(req, &len, sizeof(len)); 1608 return (error); 1609 } 1610 1611 SYSCTL_PROC(_vfs, OID_AUTO, worklist_len, CTLTYPE_INT | CTLFLAG_RD, NULL, 0, 1612 sysctl_vfs_worklist_len, "I", "Syncer thread worklist length"); 1613 1614 static struct proc *updateproc; 1615 static void sched_sync(void); 1616 static struct kproc_desc up_kp = { 1617 "syncer", 1618 sched_sync, 1619 &updateproc 1620 }; 1621 SYSINIT(syncer, SI_SUB_KTHREAD_UPDATE, SI_ORDER_FIRST, kproc_start, &up_kp); 1622 1623 static int 1624 sync_vnode(struct synclist *slp, struct bufobj **bo, struct thread *td) 1625 { 1626 struct vnode *vp; 1627 struct mount *mp; 1628 1629 *bo = LIST_FIRST(slp); 1630 if (*bo == NULL) 1631 return (0); 1632 vp = (*bo)->__bo_vnode; /* XXX */ 1633 if (VOP_ISLOCKED(vp) != 0 || VI_TRYLOCK(vp) == 0) 1634 return (1); 1635 /* 1636 * We use vhold in case the vnode does not 1637 * successfully sync. vhold prevents the vnode from 1638 * going away when we unlock the sync_mtx so that 1639 * we can acquire the vnode interlock. 1640 */ 1641 vholdl(vp); 1642 mtx_unlock(&sync_mtx); 1643 VI_UNLOCK(vp); 1644 if (vn_start_write(vp, &mp, V_NOWAIT) != 0) { 1645 vdrop(vp); 1646 mtx_lock(&sync_mtx); 1647 return (*bo == LIST_FIRST(slp)); 1648 } 1649 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 1650 (void) VOP_FSYNC(vp, MNT_LAZY, td); 1651 VOP_UNLOCK(vp, 0); 1652 vn_finished_write(mp); 1653 BO_LOCK(*bo); 1654 if (((*bo)->bo_flag & BO_ONWORKLST) != 0) { 1655 /* 1656 * Put us back on the worklist. The worklist 1657 * routine will remove us from our current 1658 * position and then add us back in at a later 1659 * position. 1660 */ 1661 vn_syncer_add_to_worklist(*bo, syncdelay); 1662 } 1663 BO_UNLOCK(*bo); 1664 vdrop(vp); 1665 mtx_lock(&sync_mtx); 1666 return (0); 1667 } 1668 1669 /* 1670 * System filesystem synchronizer daemon. 1671 */ 1672 static void 1673 sched_sync(void) 1674 { 1675 struct synclist *gnext, *next; 1676 struct synclist *gslp, *slp; 1677 struct bufobj *bo; 1678 long starttime; 1679 struct thread *td = curthread; 1680 static int dummychan; 1681 int last_work_seen; 1682 int net_worklist_len; 1683 int syncer_final_iter; 1684 int first_printf; 1685 int error; 1686 1687 last_work_seen = 0; 1688 syncer_final_iter = 0; 1689 first_printf = 1; 1690 syncer_state = SYNCER_RUNNING; 1691 starttime = time_uptime; 1692 td->td_pflags |= TDP_NORUNNINGBUF; 1693 1694 EVENTHANDLER_REGISTER(shutdown_pre_sync, syncer_shutdown, td->td_proc, 1695 SHUTDOWN_PRI_LAST); 1696 1697 mtx_lock(&sync_mtx); 1698 for (;;) { 1699 if (syncer_state == SYNCER_FINAL_DELAY && 1700 syncer_final_iter == 0) { 1701 mtx_unlock(&sync_mtx); 1702 kproc_suspend_check(td->td_proc); 1703 mtx_lock(&sync_mtx); 1704 } 1705 net_worklist_len = syncer_worklist_len - sync_vnode_count; 1706 if (syncer_state != SYNCER_RUNNING && 1707 starttime != time_uptime) { 1708 if (first_printf) { 1709 printf("\nSyncing disks, vnodes remaining..."); 1710 first_printf = 0; 1711 } 1712 printf("%d ", net_worklist_len); 1713 } 1714 starttime = time_uptime; 1715 1716 /* 1717 * Push files whose dirty time has expired. Be careful 1718 * of interrupt race on slp queue. 1719 * 1720 * Skip over empty worklist slots when shutting down. 1721 */ 1722 do { 1723 slp = &syncer_workitem_pending[WI_MPSAFEQ][syncer_delayno]; 1724 gslp = &syncer_workitem_pending[WI_GIANTQ][syncer_delayno]; 1725 syncer_delayno += 1; 1726 if (syncer_delayno == syncer_maxdelay) 1727 syncer_delayno = 0; 1728 next = &syncer_workitem_pending[WI_MPSAFEQ][syncer_delayno]; 1729 gnext = &syncer_workitem_pending[WI_GIANTQ][syncer_delayno]; 1730 /* 1731 * If the worklist has wrapped since the 1732 * it was emptied of all but syncer vnodes, 1733 * switch to the FINAL_DELAY state and run 1734 * for one more second. 1735 */ 1736 if (syncer_state == SYNCER_SHUTTING_DOWN && 1737 net_worklist_len == 0 && 1738 last_work_seen == syncer_delayno) { 1739 syncer_state = SYNCER_FINAL_DELAY; 1740 syncer_final_iter = SYNCER_SHUTDOWN_SPEEDUP; 1741 } 1742 } while (syncer_state != SYNCER_RUNNING && LIST_EMPTY(slp) && 1743 LIST_EMPTY(gslp) && syncer_worklist_len > 0); 1744 1745 /* 1746 * Keep track of the last time there was anything 1747 * on the worklist other than syncer vnodes. 1748 * Return to the SHUTTING_DOWN state if any 1749 * new work appears. 1750 */ 1751 if (net_worklist_len > 0 || syncer_state == SYNCER_RUNNING) 1752 last_work_seen = syncer_delayno; 1753 if (net_worklist_len > 0 && syncer_state == SYNCER_FINAL_DELAY) 1754 syncer_state = SYNCER_SHUTTING_DOWN; 1755 while (!LIST_EMPTY(slp)) { 1756 error = sync_vnode(slp, &bo, td); 1757 if (error == 1) { 1758 LIST_REMOVE(bo, bo_synclist); 1759 LIST_INSERT_HEAD(next, bo, bo_synclist); 1760 continue; 1761 } 1762 } 1763 if (!LIST_EMPTY(gslp)) { 1764 mtx_unlock(&sync_mtx); 1765 mtx_lock(&Giant); 1766 mtx_lock(&sync_mtx); 1767 while (!LIST_EMPTY(gslp)) { 1768 error = sync_vnode(gslp, &bo, td); 1769 if (error == 1) { 1770 LIST_REMOVE(bo, bo_synclist); 1771 LIST_INSERT_HEAD(gnext, bo, 1772 bo_synclist); 1773 continue; 1774 } 1775 } 1776 mtx_unlock(&Giant); 1777 } 1778 if (syncer_state == SYNCER_FINAL_DELAY && syncer_final_iter > 0) 1779 syncer_final_iter--; 1780 /* 1781 * The variable rushjob allows the kernel to speed up the 1782 * processing of the filesystem syncer process. A rushjob 1783 * value of N tells the filesystem syncer to process the next 1784 * N seconds worth of work on its queue ASAP. Currently rushjob 1785 * is used by the soft update code to speed up the filesystem 1786 * syncer process when the incore state is getting so far 1787 * ahead of the disk that the kernel memory pool is being 1788 * threatened with exhaustion. 1789 */ 1790 if (rushjob > 0) { 1791 rushjob -= 1; 1792 continue; 1793 } 1794 /* 1795 * Just sleep for a short period of time between 1796 * iterations when shutting down to allow some I/O 1797 * to happen. 1798 * 1799 * If it has taken us less than a second to process the 1800 * current work, then wait. Otherwise start right over 1801 * again. We can still lose time if any single round 1802 * takes more than two seconds, but it does not really 1803 * matter as we are just trying to generally pace the 1804 * filesystem activity. 1805 */ 1806 if (syncer_state != SYNCER_RUNNING) 1807 msleep(&dummychan, &sync_mtx, PPAUSE, "syncfnl", 1808 hz / SYNCER_SHUTDOWN_SPEEDUP); 1809 else if (time_uptime == starttime) 1810 msleep(&lbolt, &sync_mtx, PPAUSE, "syncer", 0); 1811 } 1812 } 1813 1814 /* 1815 * Request the syncer daemon to speed up its work. 1816 * We never push it to speed up more than half of its 1817 * normal turn time, otherwise it could take over the cpu. 1818 */ 1819 int 1820 speedup_syncer(void) 1821 { 1822 struct thread *td; 1823 int ret = 0; 1824 1825 td = FIRST_THREAD_IN_PROC(updateproc); 1826 mtx_lock(&sync_mtx); 1827 if (rushjob < syncdelay / 2) { 1828 rushjob += 1; 1829 stat_rush_requests += 1; 1830 ret = 1; 1831 } 1832 mtx_unlock(&sync_mtx); 1833 sleepq_remove(td, &lbolt); 1834 return (ret); 1835 } 1836 1837 /* 1838 * Tell the syncer to speed up its work and run though its work 1839 * list several times, then tell it to shut down. 1840 */ 1841 static void 1842 syncer_shutdown(void *arg, int howto) 1843 { 1844 struct thread *td; 1845 1846 if (howto & RB_NOSYNC) 1847 return; 1848 td = FIRST_THREAD_IN_PROC(updateproc); 1849 mtx_lock(&sync_mtx); 1850 syncer_state = SYNCER_SHUTTING_DOWN; 1851 rushjob = 0; 1852 mtx_unlock(&sync_mtx); 1853 sleepq_remove(td, &lbolt); 1854 kproc_shutdown(arg, howto); 1855 } 1856 1857 /* 1858 * Reassign a buffer from one vnode to another. 1859 * Used to assign file specific control information 1860 * (indirect blocks) to the vnode to which they belong. 1861 */ 1862 void 1863 reassignbuf(struct buf *bp) 1864 { 1865 struct vnode *vp; 1866 struct bufobj *bo; 1867 int delay; 1868 #ifdef INVARIANTS 1869 struct bufv *bv; 1870 #endif 1871 1872 vp = bp->b_vp; 1873 bo = bp->b_bufobj; 1874 ++reassignbufcalls; 1875 1876 CTR3(KTR_BUF, "reassignbuf(%p) vp %p flags %X", 1877 bp, bp->b_vp, bp->b_flags); 1878 /* 1879 * B_PAGING flagged buffers cannot be reassigned because their vp 1880 * is not fully linked in. 1881 */ 1882 if (bp->b_flags & B_PAGING) 1883 panic("cannot reassign paging buffer"); 1884 1885 /* 1886 * Delete from old vnode list, if on one. 1887 */ 1888 BO_LOCK(bo); 1889 if (bp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN)) 1890 buf_vlist_remove(bp); 1891 else 1892 panic("reassignbuf: Buffer %p not on queue.", bp); 1893 /* 1894 * If dirty, put on list of dirty buffers; otherwise insert onto list 1895 * of clean buffers. 1896 */ 1897 if (bp->b_flags & B_DELWRI) { 1898 if ((bo->bo_flag & BO_ONWORKLST) == 0) { 1899 switch (vp->v_type) { 1900 case VDIR: 1901 delay = dirdelay; 1902 break; 1903 case VCHR: 1904 delay = metadelay; 1905 break; 1906 default: 1907 delay = filedelay; 1908 } 1909 vn_syncer_add_to_worklist(bo, delay); 1910 } 1911 buf_vlist_add(bp, bo, BX_VNDIRTY); 1912 } else { 1913 buf_vlist_add(bp, bo, BX_VNCLEAN); 1914 1915 if ((bo->bo_flag & BO_ONWORKLST) && bo->bo_dirty.bv_cnt == 0) { 1916 mtx_lock(&sync_mtx); 1917 LIST_REMOVE(bo, bo_synclist); 1918 syncer_worklist_len--; 1919 mtx_unlock(&sync_mtx); 1920 bo->bo_flag &= ~BO_ONWORKLST; 1921 } 1922 } 1923 #ifdef INVARIANTS 1924 bv = &bo->bo_clean; 1925 bp = TAILQ_FIRST(&bv->bv_hd); 1926 KASSERT(bp == NULL || bp->b_bufobj == bo, 1927 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 1928 bp = TAILQ_LAST(&bv->bv_hd, buflists); 1929 KASSERT(bp == NULL || bp->b_bufobj == bo, 1930 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 1931 bv = &bo->bo_dirty; 1932 bp = TAILQ_FIRST(&bv->bv_hd); 1933 KASSERT(bp == NULL || bp->b_bufobj == bo, 1934 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 1935 bp = TAILQ_LAST(&bv->bv_hd, buflists); 1936 KASSERT(bp == NULL || bp->b_bufobj == bo, 1937 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 1938 #endif 1939 BO_UNLOCK(bo); 1940 } 1941 1942 /* 1943 * Increment the use and hold counts on the vnode, taking care to reference 1944 * the driver's usecount if this is a chardev. The vholdl() will remove 1945 * the vnode from the free list if it is presently free. Requires the 1946 * vnode interlock and returns with it held. 1947 */ 1948 static void 1949 v_incr_usecount(struct vnode *vp) 1950 { 1951 1952 CTR3(KTR_VFS, "v_incr_usecount: vp %p holdcnt %d usecount %d\n", 1953 vp, vp->v_holdcnt, vp->v_usecount); 1954 vp->v_usecount++; 1955 if (vp->v_type == VCHR && vp->v_rdev != NULL) { 1956 dev_lock(); 1957 vp->v_rdev->si_usecount++; 1958 dev_unlock(); 1959 } 1960 vholdl(vp); 1961 } 1962 1963 /* 1964 * Turn a holdcnt into a use+holdcnt such that only one call to 1965 * v_decr_usecount is needed. 1966 */ 1967 static void 1968 v_upgrade_usecount(struct vnode *vp) 1969 { 1970 1971 CTR3(KTR_VFS, "v_upgrade_usecount: vp %p holdcnt %d usecount %d\n", 1972 vp, vp->v_holdcnt, vp->v_usecount); 1973 vp->v_usecount++; 1974 if (vp->v_type == VCHR && vp->v_rdev != NULL) { 1975 dev_lock(); 1976 vp->v_rdev->si_usecount++; 1977 dev_unlock(); 1978 } 1979 } 1980 1981 /* 1982 * Decrement the vnode use and hold count along with the driver's usecount 1983 * if this is a chardev. The vdropl() below releases the vnode interlock 1984 * as it may free the vnode. 1985 */ 1986 static void 1987 v_decr_usecount(struct vnode *vp) 1988 { 1989 1990 CTR3(KTR_VFS, "v_decr_usecount: vp %p holdcnt %d usecount %d\n", 1991 vp, vp->v_holdcnt, vp->v_usecount); 1992 ASSERT_VI_LOCKED(vp, __FUNCTION__); 1993 VNASSERT(vp->v_usecount > 0, vp, 1994 ("v_decr_usecount: negative usecount")); 1995 vp->v_usecount--; 1996 if (vp->v_type == VCHR && vp->v_rdev != NULL) { 1997 dev_lock(); 1998 vp->v_rdev->si_usecount--; 1999 dev_unlock(); 2000 } 2001 vdropl(vp); 2002 } 2003 2004 /* 2005 * Decrement only the use count and driver use count. This is intended to 2006 * be paired with a follow on vdropl() to release the remaining hold count. 2007 * In this way we may vgone() a vnode with a 0 usecount without risk of 2008 * having it end up on a free list because the hold count is kept above 0. 2009 */ 2010 static void 2011 v_decr_useonly(struct vnode *vp) 2012 { 2013 2014 CTR3(KTR_VFS, "v_decr_useonly: vp %p holdcnt %d usecount %d\n", 2015 vp, vp->v_holdcnt, vp->v_usecount); 2016 ASSERT_VI_LOCKED(vp, __FUNCTION__); 2017 VNASSERT(vp->v_usecount > 0, vp, 2018 ("v_decr_useonly: negative usecount")); 2019 vp->v_usecount--; 2020 if (vp->v_type == VCHR && vp->v_rdev != NULL) { 2021 dev_lock(); 2022 vp->v_rdev->si_usecount--; 2023 dev_unlock(); 2024 } 2025 } 2026 2027 /* 2028 * Grab a particular vnode from the free list, increment its 2029 * reference count and lock it. VI_DOOMED is set if the vnode 2030 * is being destroyed. Only callers who specify LK_RETRY will 2031 * see doomed vnodes. If inactive processing was delayed in 2032 * vput try to do it here. 2033 */ 2034 int 2035 vget(struct vnode *vp, int flags, struct thread *td) 2036 { 2037 int error; 2038 2039 error = 0; 2040 VFS_ASSERT_GIANT(vp->v_mount); 2041 if ((flags & LK_INTERLOCK) == 0) 2042 VI_LOCK(vp); 2043 vholdl(vp); 2044 if ((error = vn_lock(vp, flags | LK_INTERLOCK)) != 0) { 2045 vdrop(vp); 2046 return (error); 2047 } 2048 if (vp->v_iflag & VI_DOOMED && (flags & LK_RETRY) == 0) 2049 panic("vget: vn_lock failed to return ENOENT\n"); 2050 VI_LOCK(vp); 2051 /* Upgrade our holdcnt to a usecount. */ 2052 v_upgrade_usecount(vp); 2053 /* 2054 * We don't guarantee that any particular close will 2055 * trigger inactive processing so just make a best effort 2056 * here at preventing a reference to a removed file. If 2057 * we don't succeed no harm is done. 2058 */ 2059 if (vp->v_iflag & VI_OWEINACT) { 2060 if (VOP_ISLOCKED(vp) == LK_EXCLUSIVE && 2061 (flags & LK_NOWAIT) == 0) 2062 vinactive(vp, td); 2063 vp->v_iflag &= ~VI_OWEINACT; 2064 } 2065 VI_UNLOCK(vp); 2066 return (0); 2067 } 2068 2069 /* 2070 * Increase the reference count of a vnode. 2071 */ 2072 void 2073 vref(struct vnode *vp) 2074 { 2075 2076 VI_LOCK(vp); 2077 v_incr_usecount(vp); 2078 VI_UNLOCK(vp); 2079 } 2080 2081 /* 2082 * Return reference count of a vnode. 2083 * 2084 * The results of this call are only guaranteed when some mechanism other 2085 * than the VI lock is used to stop other processes from gaining references 2086 * to the vnode. This may be the case if the caller holds the only reference. 2087 * This is also useful when stale data is acceptable as race conditions may 2088 * be accounted for by some other means. 2089 */ 2090 int 2091 vrefcnt(struct vnode *vp) 2092 { 2093 int usecnt; 2094 2095 VI_LOCK(vp); 2096 usecnt = vp->v_usecount; 2097 VI_UNLOCK(vp); 2098 2099 return (usecnt); 2100 } 2101 2102 2103 /* 2104 * Vnode put/release. 2105 * If count drops to zero, call inactive routine and return to freelist. 2106 */ 2107 void 2108 vrele(struct vnode *vp) 2109 { 2110 struct thread *td = curthread; /* XXX */ 2111 2112 KASSERT(vp != NULL, ("vrele: null vp")); 2113 VFS_ASSERT_GIANT(vp->v_mount); 2114 2115 VI_LOCK(vp); 2116 2117 /* Skip this v_writecount check if we're going to panic below. */ 2118 VNASSERT(vp->v_writecount < vp->v_usecount || vp->v_usecount < 1, vp, 2119 ("vrele: missed vn_close")); 2120 2121 if (vp->v_usecount > 1 || ((vp->v_iflag & VI_DOINGINACT) && 2122 vp->v_usecount == 1)) { 2123 v_decr_usecount(vp); 2124 return; 2125 } 2126 if (vp->v_usecount != 1) { 2127 #ifdef DIAGNOSTIC 2128 vprint("vrele: negative ref count", vp); 2129 #endif 2130 VI_UNLOCK(vp); 2131 panic("vrele: negative ref cnt"); 2132 } 2133 /* 2134 * We want to hold the vnode until the inactive finishes to 2135 * prevent vgone() races. We drop the use count here and the 2136 * hold count below when we're done. 2137 */ 2138 v_decr_useonly(vp); 2139 /* 2140 * We must call VOP_INACTIVE with the node locked. Mark 2141 * as VI_DOINGINACT to avoid recursion. 2142 */ 2143 vp->v_iflag |= VI_OWEINACT; 2144 if (vn_lock(vp, LK_EXCLUSIVE | LK_INTERLOCK) == 0) { 2145 VI_LOCK(vp); 2146 if (vp->v_usecount > 0) 2147 vp->v_iflag &= ~VI_OWEINACT; 2148 if (vp->v_iflag & VI_OWEINACT) 2149 vinactive(vp, td); 2150 VOP_UNLOCK(vp, 0); 2151 } else { 2152 VI_LOCK(vp); 2153 if (vp->v_usecount > 0) 2154 vp->v_iflag &= ~VI_OWEINACT; 2155 } 2156 vdropl(vp); 2157 } 2158 2159 /* 2160 * Release an already locked vnode. This give the same effects as 2161 * unlock+vrele(), but takes less time and avoids releasing and 2162 * re-aquiring the lock (as vrele() acquires the lock internally.) 2163 */ 2164 void 2165 vput(struct vnode *vp) 2166 { 2167 struct thread *td = curthread; /* XXX */ 2168 int error; 2169 2170 KASSERT(vp != NULL, ("vput: null vp")); 2171 ASSERT_VOP_LOCKED(vp, "vput"); 2172 VFS_ASSERT_GIANT(vp->v_mount); 2173 VI_LOCK(vp); 2174 /* Skip this v_writecount check if we're going to panic below. */ 2175 VNASSERT(vp->v_writecount < vp->v_usecount || vp->v_usecount < 1, vp, 2176 ("vput: missed vn_close")); 2177 error = 0; 2178 2179 if (vp->v_usecount > 1 || ((vp->v_iflag & VI_DOINGINACT) && 2180 vp->v_usecount == 1)) { 2181 VOP_UNLOCK(vp, 0); 2182 v_decr_usecount(vp); 2183 return; 2184 } 2185 2186 if (vp->v_usecount != 1) { 2187 #ifdef DIAGNOSTIC 2188 vprint("vput: negative ref count", vp); 2189 #endif 2190 panic("vput: negative ref cnt"); 2191 } 2192 /* 2193 * We want to hold the vnode until the inactive finishes to 2194 * prevent vgone() races. We drop the use count here and the 2195 * hold count below when we're done. 2196 */ 2197 v_decr_useonly(vp); 2198 vp->v_iflag |= VI_OWEINACT; 2199 if (VOP_ISLOCKED(vp) != LK_EXCLUSIVE) { 2200 error = VOP_LOCK(vp, LK_UPGRADE|LK_INTERLOCK|LK_NOWAIT); 2201 VI_LOCK(vp); 2202 if (error) { 2203 if (vp->v_usecount > 0) 2204 vp->v_iflag &= ~VI_OWEINACT; 2205 goto done; 2206 } 2207 } 2208 if (vp->v_usecount > 0) 2209 vp->v_iflag &= ~VI_OWEINACT; 2210 if (vp->v_iflag & VI_OWEINACT) 2211 vinactive(vp, td); 2212 VOP_UNLOCK(vp, 0); 2213 done: 2214 vdropl(vp); 2215 } 2216 2217 /* 2218 * Somebody doesn't want the vnode recycled. 2219 */ 2220 void 2221 vhold(struct vnode *vp) 2222 { 2223 2224 VI_LOCK(vp); 2225 vholdl(vp); 2226 VI_UNLOCK(vp); 2227 } 2228 2229 void 2230 vholdl(struct vnode *vp) 2231 { 2232 2233 vp->v_holdcnt++; 2234 if (VSHOULDBUSY(vp)) 2235 vbusy(vp); 2236 } 2237 2238 /* 2239 * Note that there is one less who cares about this vnode. vdrop() is the 2240 * opposite of vhold(). 2241 */ 2242 void 2243 vdrop(struct vnode *vp) 2244 { 2245 2246 VI_LOCK(vp); 2247 vdropl(vp); 2248 } 2249 2250 /* 2251 * Drop the hold count of the vnode. If this is the last reference to 2252 * the vnode we will free it if it has been vgone'd otherwise it is 2253 * placed on the free list. 2254 */ 2255 void 2256 vdropl(struct vnode *vp) 2257 { 2258 2259 ASSERT_VI_LOCKED(vp, "vdropl"); 2260 if (vp->v_holdcnt <= 0) 2261 panic("vdrop: holdcnt %d", vp->v_holdcnt); 2262 vp->v_holdcnt--; 2263 if (vp->v_holdcnt == 0) { 2264 if (vp->v_iflag & VI_DOOMED) { 2265 vdestroy(vp); 2266 return; 2267 } else 2268 vfree(vp); 2269 } 2270 VI_UNLOCK(vp); 2271 } 2272 2273 /* 2274 * Call VOP_INACTIVE on the vnode and manage the DOINGINACT and OWEINACT 2275 * flags. DOINGINACT prevents us from recursing in calls to vinactive. 2276 * OWEINACT tracks whether a vnode missed a call to inactive due to a 2277 * failed lock upgrade. 2278 */ 2279 static void 2280 vinactive(struct vnode *vp, struct thread *td) 2281 { 2282 2283 ASSERT_VOP_LOCKED(vp, "vinactive"); 2284 ASSERT_VI_LOCKED(vp, "vinactive"); 2285 VNASSERT((vp->v_iflag & VI_DOINGINACT) == 0, vp, 2286 ("vinactive: recursed on VI_DOINGINACT")); 2287 vp->v_iflag |= VI_DOINGINACT; 2288 vp->v_iflag &= ~VI_OWEINACT; 2289 VI_UNLOCK(vp); 2290 VOP_INACTIVE(vp, td); 2291 VI_LOCK(vp); 2292 VNASSERT(vp->v_iflag & VI_DOINGINACT, vp, 2293 ("vinactive: lost VI_DOINGINACT")); 2294 vp->v_iflag &= ~VI_DOINGINACT; 2295 } 2296 2297 /* 2298 * Remove any vnodes in the vnode table belonging to mount point mp. 2299 * 2300 * If FORCECLOSE is not specified, there should not be any active ones, 2301 * return error if any are found (nb: this is a user error, not a 2302 * system error). If FORCECLOSE is specified, detach any active vnodes 2303 * that are found. 2304 * 2305 * If WRITECLOSE is set, only flush out regular file vnodes open for 2306 * writing. 2307 * 2308 * SKIPSYSTEM causes any vnodes marked VV_SYSTEM to be skipped. 2309 * 2310 * `rootrefs' specifies the base reference count for the root vnode 2311 * of this filesystem. The root vnode is considered busy if its 2312 * v_usecount exceeds this value. On a successful return, vflush(, td) 2313 * will call vrele() on the root vnode exactly rootrefs times. 2314 * If the SKIPSYSTEM or WRITECLOSE flags are specified, rootrefs must 2315 * be zero. 2316 */ 2317 #ifdef DIAGNOSTIC 2318 static int busyprt = 0; /* print out busy vnodes */ 2319 SYSCTL_INT(_debug, OID_AUTO, busyprt, CTLFLAG_RW, &busyprt, 0, ""); 2320 #endif 2321 2322 int 2323 vflush( struct mount *mp, int rootrefs, int flags, struct thread *td) 2324 { 2325 struct vnode *vp, *mvp, *rootvp = NULL; 2326 struct vattr vattr; 2327 int busy = 0, error; 2328 2329 CTR1(KTR_VFS, "vflush: mp %p", mp); 2330 if (rootrefs > 0) { 2331 KASSERT((flags & (SKIPSYSTEM | WRITECLOSE)) == 0, 2332 ("vflush: bad args")); 2333 /* 2334 * Get the filesystem root vnode. We can vput() it 2335 * immediately, since with rootrefs > 0, it won't go away. 2336 */ 2337 if ((error = VFS_ROOT(mp, LK_EXCLUSIVE, &rootvp, td)) != 0) 2338 return (error); 2339 vput(rootvp); 2340 2341 } 2342 MNT_ILOCK(mp); 2343 loop: 2344 MNT_VNODE_FOREACH(vp, mp, mvp) { 2345 2346 VI_LOCK(vp); 2347 vholdl(vp); 2348 MNT_IUNLOCK(mp); 2349 error = vn_lock(vp, LK_INTERLOCK | LK_EXCLUSIVE); 2350 if (error) { 2351 vdrop(vp); 2352 MNT_ILOCK(mp); 2353 MNT_VNODE_FOREACH_ABORT_ILOCKED(mp, mvp); 2354 goto loop; 2355 } 2356 /* 2357 * Skip over a vnodes marked VV_SYSTEM. 2358 */ 2359 if ((flags & SKIPSYSTEM) && (vp->v_vflag & VV_SYSTEM)) { 2360 VOP_UNLOCK(vp, 0); 2361 vdrop(vp); 2362 MNT_ILOCK(mp); 2363 continue; 2364 } 2365 /* 2366 * If WRITECLOSE is set, flush out unlinked but still open 2367 * files (even if open only for reading) and regular file 2368 * vnodes open for writing. 2369 */ 2370 if (flags & WRITECLOSE) { 2371 error = VOP_GETATTR(vp, &vattr, td->td_ucred, td); 2372 VI_LOCK(vp); 2373 2374 if ((vp->v_type == VNON || 2375 (error == 0 && vattr.va_nlink > 0)) && 2376 (vp->v_writecount == 0 || vp->v_type != VREG)) { 2377 VOP_UNLOCK(vp, 0); 2378 vdropl(vp); 2379 MNT_ILOCK(mp); 2380 continue; 2381 } 2382 } else 2383 VI_LOCK(vp); 2384 /* 2385 * With v_usecount == 0, all we need to do is clear out the 2386 * vnode data structures and we are done. 2387 * 2388 * If FORCECLOSE is set, forcibly close the vnode. 2389 */ 2390 if (vp->v_usecount == 0 || (flags & FORCECLOSE)) { 2391 VNASSERT(vp->v_usecount == 0 || 2392 (vp->v_type != VCHR && vp->v_type != VBLK), vp, 2393 ("device VNODE %p is FORCECLOSED", vp)); 2394 vgonel(vp); 2395 } else { 2396 busy++; 2397 #ifdef DIAGNOSTIC 2398 if (busyprt) 2399 vprint("vflush: busy vnode", vp); 2400 #endif 2401 } 2402 VOP_UNLOCK(vp, 0); 2403 vdropl(vp); 2404 MNT_ILOCK(mp); 2405 } 2406 MNT_IUNLOCK(mp); 2407 if (rootrefs > 0 && (flags & FORCECLOSE) == 0) { 2408 /* 2409 * If just the root vnode is busy, and if its refcount 2410 * is equal to `rootrefs', then go ahead and kill it. 2411 */ 2412 VI_LOCK(rootvp); 2413 KASSERT(busy > 0, ("vflush: not busy")); 2414 VNASSERT(rootvp->v_usecount >= rootrefs, rootvp, 2415 ("vflush: usecount %d < rootrefs %d", 2416 rootvp->v_usecount, rootrefs)); 2417 if (busy == 1 && rootvp->v_usecount == rootrefs) { 2418 VOP_LOCK(rootvp, LK_EXCLUSIVE|LK_INTERLOCK); 2419 vgone(rootvp); 2420 VOP_UNLOCK(rootvp, 0); 2421 busy = 0; 2422 } else 2423 VI_UNLOCK(rootvp); 2424 } 2425 if (busy) 2426 return (EBUSY); 2427 for (; rootrefs > 0; rootrefs--) 2428 vrele(rootvp); 2429 return (0); 2430 } 2431 2432 /* 2433 * Recycle an unused vnode to the front of the free list. 2434 */ 2435 int 2436 vrecycle(struct vnode *vp, struct thread *td) 2437 { 2438 int recycled; 2439 2440 ASSERT_VOP_LOCKED(vp, "vrecycle"); 2441 recycled = 0; 2442 VI_LOCK(vp); 2443 if (vp->v_usecount == 0) { 2444 recycled = 1; 2445 vgonel(vp); 2446 } 2447 VI_UNLOCK(vp); 2448 return (recycled); 2449 } 2450 2451 /* 2452 * Eliminate all activity associated with a vnode 2453 * in preparation for reuse. 2454 */ 2455 void 2456 vgone(struct vnode *vp) 2457 { 2458 VI_LOCK(vp); 2459 vgonel(vp); 2460 VI_UNLOCK(vp); 2461 } 2462 2463 /* 2464 * vgone, with the vp interlock held. 2465 */ 2466 void 2467 vgonel(struct vnode *vp) 2468 { 2469 struct thread *td; 2470 int oweinact; 2471 int active; 2472 struct mount *mp; 2473 2474 CTR1(KTR_VFS, "vgonel: vp %p", vp); 2475 ASSERT_VOP_LOCKED(vp, "vgonel"); 2476 ASSERT_VI_LOCKED(vp, "vgonel"); 2477 VNASSERT(vp->v_holdcnt, vp, 2478 ("vgonel: vp %p has no reference.", vp)); 2479 td = curthread; 2480 2481 /* 2482 * Don't vgonel if we're already doomed. 2483 */ 2484 if (vp->v_iflag & VI_DOOMED) 2485 return; 2486 vp->v_iflag |= VI_DOOMED; 2487 /* 2488 * Check to see if the vnode is in use. If so, we have to call 2489 * VOP_CLOSE() and VOP_INACTIVE(). 2490 */ 2491 active = vp->v_usecount; 2492 oweinact = (vp->v_iflag & VI_OWEINACT); 2493 VI_UNLOCK(vp); 2494 /* 2495 * Clean out any buffers associated with the vnode. 2496 * If the flush fails, just toss the buffers. 2497 */ 2498 mp = NULL; 2499 if (!TAILQ_EMPTY(&vp->v_bufobj.bo_dirty.bv_hd)) 2500 (void) vn_start_secondary_write(vp, &mp, V_WAIT); 2501 if (vinvalbuf(vp, V_SAVE, td, 0, 0) != 0) 2502 vinvalbuf(vp, 0, td, 0, 0); 2503 2504 /* 2505 * If purging an active vnode, it must be closed and 2506 * deactivated before being reclaimed. 2507 */ 2508 if (active) 2509 VOP_CLOSE(vp, FNONBLOCK, NOCRED, td); 2510 if (oweinact || active) { 2511 VI_LOCK(vp); 2512 if ((vp->v_iflag & VI_DOINGINACT) == 0) 2513 vinactive(vp, td); 2514 VI_UNLOCK(vp); 2515 } 2516 /* 2517 * Reclaim the vnode. 2518 */ 2519 if (VOP_RECLAIM(vp, td)) 2520 panic("vgone: cannot reclaim"); 2521 if (mp != NULL) 2522 vn_finished_secondary_write(mp); 2523 VNASSERT(vp->v_object == NULL, vp, 2524 ("vop_reclaim left v_object vp=%p, tag=%s", vp, vp->v_tag)); 2525 /* 2526 * Clear the advisory locks and wake up waiting threads. 2527 */ 2528 lf_purgelocks(vp, &(vp->v_lockf)); 2529 /* 2530 * Delete from old mount point vnode list. 2531 */ 2532 delmntque(vp); 2533 cache_purge(vp); 2534 /* 2535 * Done with purge, reset to the standard lock and invalidate 2536 * the vnode. 2537 */ 2538 VI_LOCK(vp); 2539 vp->v_vnlock = &vp->v_lock; 2540 vp->v_op = &dead_vnodeops; 2541 vp->v_tag = "none"; 2542 vp->v_type = VBAD; 2543 } 2544 2545 /* 2546 * Calculate the total number of references to a special device. 2547 */ 2548 int 2549 vcount(struct vnode *vp) 2550 { 2551 int count; 2552 2553 dev_lock(); 2554 count = vp->v_rdev->si_usecount; 2555 dev_unlock(); 2556 return (count); 2557 } 2558 2559 /* 2560 * Same as above, but using the struct cdev *as argument 2561 */ 2562 int 2563 count_dev(struct cdev *dev) 2564 { 2565 int count; 2566 2567 dev_lock(); 2568 count = dev->si_usecount; 2569 dev_unlock(); 2570 return(count); 2571 } 2572 2573 /* 2574 * Print out a description of a vnode. 2575 */ 2576 static char *typename[] = 2577 {"VNON", "VREG", "VDIR", "VBLK", "VCHR", "VLNK", "VSOCK", "VFIFO", "VBAD", 2578 "VMARKER"}; 2579 2580 void 2581 vn_printf(struct vnode *vp, const char *fmt, ...) 2582 { 2583 va_list ap; 2584 char buf[256], buf2[16]; 2585 u_long flags; 2586 2587 va_start(ap, fmt); 2588 vprintf(fmt, ap); 2589 va_end(ap); 2590 printf("%p: ", (void *)vp); 2591 printf("tag %s, type %s\n", vp->v_tag, typename[vp->v_type]); 2592 printf(" usecount %d, writecount %d, refcount %d mountedhere %p\n", 2593 vp->v_usecount, vp->v_writecount, vp->v_holdcnt, vp->v_mountedhere); 2594 buf[0] = '\0'; 2595 buf[1] = '\0'; 2596 if (vp->v_vflag & VV_ROOT) 2597 strlcat(buf, "|VV_ROOT", sizeof(buf)); 2598 if (vp->v_vflag & VV_ISTTY) 2599 strlcat(buf, "|VV_ISTTY", sizeof(buf)); 2600 if (vp->v_vflag & VV_NOSYNC) 2601 strlcat(buf, "|VV_NOSYNC", sizeof(buf)); 2602 if (vp->v_vflag & VV_CACHEDLABEL) 2603 strlcat(buf, "|VV_CACHEDLABEL", sizeof(buf)); 2604 if (vp->v_vflag & VV_TEXT) 2605 strlcat(buf, "|VV_TEXT", sizeof(buf)); 2606 if (vp->v_vflag & VV_COPYONWRITE) 2607 strlcat(buf, "|VV_COPYONWRITE", sizeof(buf)); 2608 if (vp->v_vflag & VV_SYSTEM) 2609 strlcat(buf, "|VV_SYSTEM", sizeof(buf)); 2610 if (vp->v_vflag & VV_PROCDEP) 2611 strlcat(buf, "|VV_PROCDEP", sizeof(buf)); 2612 if (vp->v_vflag & VV_NOKNOTE) 2613 strlcat(buf, "|VV_NOKNOTE", sizeof(buf)); 2614 if (vp->v_vflag & VV_DELETED) 2615 strlcat(buf, "|VV_DELETED", sizeof(buf)); 2616 if (vp->v_vflag & VV_MD) 2617 strlcat(buf, "|VV_MD", sizeof(buf)); 2618 flags = vp->v_vflag & ~(VV_ROOT | VV_ISTTY | VV_NOSYNC | 2619 VV_CACHEDLABEL | VV_TEXT | VV_COPYONWRITE | VV_SYSTEM | VV_PROCDEP | 2620 VV_NOKNOTE | VV_DELETED | VV_MD); 2621 if (flags != 0) { 2622 snprintf(buf2, sizeof(buf2), "|VV(0x%lx)", flags); 2623 strlcat(buf, buf2, sizeof(buf)); 2624 } 2625 if (vp->v_iflag & VI_MOUNT) 2626 strlcat(buf, "|VI_MOUNT", sizeof(buf)); 2627 if (vp->v_iflag & VI_AGE) 2628 strlcat(buf, "|VI_AGE", sizeof(buf)); 2629 if (vp->v_iflag & VI_DOOMED) 2630 strlcat(buf, "|VI_DOOMED", sizeof(buf)); 2631 if (vp->v_iflag & VI_FREE) 2632 strlcat(buf, "|VI_FREE", sizeof(buf)); 2633 if (vp->v_iflag & VI_OBJDIRTY) 2634 strlcat(buf, "|VI_OBJDIRTY", sizeof(buf)); 2635 if (vp->v_iflag & VI_DOINGINACT) 2636 strlcat(buf, "|VI_DOINGINACT", sizeof(buf)); 2637 if (vp->v_iflag & VI_OWEINACT) 2638 strlcat(buf, "|VI_OWEINACT", sizeof(buf)); 2639 flags = vp->v_iflag & ~(VI_MOUNT | VI_AGE | VI_DOOMED | VI_FREE | 2640 VI_OBJDIRTY | VI_DOINGINACT | VI_OWEINACT); 2641 if (flags != 0) { 2642 snprintf(buf2, sizeof(buf2), "|VI(0x%lx)", flags); 2643 strlcat(buf, buf2, sizeof(buf)); 2644 } 2645 printf(" flags (%s)\n", buf + 1); 2646 if (mtx_owned(VI_MTX(vp))) 2647 printf(" VI_LOCKed"); 2648 if (vp->v_object != NULL) 2649 printf(" v_object %p ref %d pages %d\n", 2650 vp->v_object, vp->v_object->ref_count, 2651 vp->v_object->resident_page_count); 2652 printf(" "); 2653 lockmgr_printinfo(vp->v_vnlock); 2654 printf("\n"); 2655 if (vp->v_data != NULL) 2656 VOP_PRINT(vp); 2657 } 2658 2659 #ifdef DDB 2660 /* 2661 * List all of the locked vnodes in the system. 2662 * Called when debugging the kernel. 2663 */ 2664 DB_SHOW_COMMAND(lockedvnods, lockedvnodes) 2665 { 2666 struct mount *mp, *nmp; 2667 struct vnode *vp; 2668 2669 /* 2670 * Note: because this is DDB, we can't obey the locking semantics 2671 * for these structures, which means we could catch an inconsistent 2672 * state and dereference a nasty pointer. Not much to be done 2673 * about that. 2674 */ 2675 db_printf("Locked vnodes\n"); 2676 for (mp = TAILQ_FIRST(&mountlist); mp != NULL; mp = nmp) { 2677 nmp = TAILQ_NEXT(mp, mnt_list); 2678 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) { 2679 if (vp->v_type != VMARKER && 2680 VOP_ISLOCKED(vp)) 2681 vprint("", vp); 2682 } 2683 nmp = TAILQ_NEXT(mp, mnt_list); 2684 } 2685 } 2686 2687 /* 2688 * Show details about the given vnode. 2689 */ 2690 DB_SHOW_COMMAND(vnode, db_show_vnode) 2691 { 2692 struct vnode *vp; 2693 2694 if (!have_addr) 2695 return; 2696 vp = (struct vnode *)addr; 2697 vn_printf(vp, "vnode "); 2698 } 2699 2700 /* 2701 * Show details about the given mount point. 2702 */ 2703 DB_SHOW_COMMAND(mount, db_show_mount) 2704 { 2705 struct mount *mp; 2706 struct statfs *sp; 2707 struct vnode *vp; 2708 char buf[512]; 2709 u_int flags; 2710 2711 if (!have_addr) { 2712 /* No address given, print short info about all mount points. */ 2713 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 2714 db_printf("%p %s on %s (%s)\n", mp, 2715 mp->mnt_stat.f_mntfromname, 2716 mp->mnt_stat.f_mntonname, 2717 mp->mnt_stat.f_fstypename); 2718 if (db_pager_quit) 2719 break; 2720 } 2721 db_printf("\nMore info: show mount <addr>\n"); 2722 return; 2723 } 2724 2725 mp = (struct mount *)addr; 2726 db_printf("%p %s on %s (%s)\n", mp, mp->mnt_stat.f_mntfromname, 2727 mp->mnt_stat.f_mntonname, mp->mnt_stat.f_fstypename); 2728 2729 buf[0] = '\0'; 2730 flags = mp->mnt_flag; 2731 #define MNT_FLAG(flag) do { \ 2732 if (flags & (flag)) { \ 2733 if (buf[0] != '\0') \ 2734 strlcat(buf, ", ", sizeof(buf)); \ 2735 strlcat(buf, (#flag) + 4, sizeof(buf)); \ 2736 flags &= ~(flag); \ 2737 } \ 2738 } while (0) 2739 MNT_FLAG(MNT_RDONLY); 2740 MNT_FLAG(MNT_SYNCHRONOUS); 2741 MNT_FLAG(MNT_NOEXEC); 2742 MNT_FLAG(MNT_NOSUID); 2743 MNT_FLAG(MNT_UNION); 2744 MNT_FLAG(MNT_ASYNC); 2745 MNT_FLAG(MNT_SUIDDIR); 2746 MNT_FLAG(MNT_SOFTDEP); 2747 MNT_FLAG(MNT_NOSYMFOLLOW); 2748 MNT_FLAG(MNT_GJOURNAL); 2749 MNT_FLAG(MNT_MULTILABEL); 2750 MNT_FLAG(MNT_ACLS); 2751 MNT_FLAG(MNT_NOATIME); 2752 MNT_FLAG(MNT_NOCLUSTERR); 2753 MNT_FLAG(MNT_NOCLUSTERW); 2754 MNT_FLAG(MNT_EXRDONLY); 2755 MNT_FLAG(MNT_EXPORTED); 2756 MNT_FLAG(MNT_DEFEXPORTED); 2757 MNT_FLAG(MNT_EXPORTANON); 2758 MNT_FLAG(MNT_EXKERB); 2759 MNT_FLAG(MNT_EXPUBLIC); 2760 MNT_FLAG(MNT_LOCAL); 2761 MNT_FLAG(MNT_QUOTA); 2762 MNT_FLAG(MNT_ROOTFS); 2763 MNT_FLAG(MNT_USER); 2764 MNT_FLAG(MNT_IGNORE); 2765 MNT_FLAG(MNT_UPDATE); 2766 MNT_FLAG(MNT_DELEXPORT); 2767 MNT_FLAG(MNT_RELOAD); 2768 MNT_FLAG(MNT_FORCE); 2769 MNT_FLAG(MNT_SNAPSHOT); 2770 MNT_FLAG(MNT_BYFSID); 2771 #undef MNT_FLAG 2772 if (flags != 0) { 2773 if (buf[0] != '\0') 2774 strlcat(buf, ", ", sizeof(buf)); 2775 snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf), 2776 "0x%08x", flags); 2777 } 2778 db_printf(" mnt_flag = %s\n", buf); 2779 2780 buf[0] = '\0'; 2781 flags = mp->mnt_kern_flag; 2782 #define MNT_KERN_FLAG(flag) do { \ 2783 if (flags & (flag)) { \ 2784 if (buf[0] != '\0') \ 2785 strlcat(buf, ", ", sizeof(buf)); \ 2786 strlcat(buf, (#flag) + 5, sizeof(buf)); \ 2787 flags &= ~(flag); \ 2788 } \ 2789 } while (0) 2790 MNT_KERN_FLAG(MNTK_UNMOUNTF); 2791 MNT_KERN_FLAG(MNTK_ASYNC); 2792 MNT_KERN_FLAG(MNTK_SOFTDEP); 2793 MNT_KERN_FLAG(MNTK_NOINSMNTQ); 2794 MNT_KERN_FLAG(MNTK_UNMOUNT); 2795 MNT_KERN_FLAG(MNTK_MWAIT); 2796 MNT_KERN_FLAG(MNTK_SUSPEND); 2797 MNT_KERN_FLAG(MNTK_SUSPEND2); 2798 MNT_KERN_FLAG(MNTK_SUSPENDED); 2799 MNT_KERN_FLAG(MNTK_MPSAFE); 2800 MNT_KERN_FLAG(MNTK_NOKNOTE); 2801 MNT_KERN_FLAG(MNTK_LOOKUP_SHARED); 2802 #undef MNT_KERN_FLAG 2803 if (flags != 0) { 2804 if (buf[0] != '\0') 2805 strlcat(buf, ", ", sizeof(buf)); 2806 snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf), 2807 "0x%08x", flags); 2808 } 2809 db_printf(" mnt_kern_flag = %s\n", buf); 2810 2811 sp = &mp->mnt_stat; 2812 db_printf(" mnt_stat = { version=%u type=%u flags=0x%016jx " 2813 "bsize=%ju iosize=%ju blocks=%ju bfree=%ju bavail=%jd files=%ju " 2814 "ffree=%jd syncwrites=%ju asyncwrites=%ju syncreads=%ju " 2815 "asyncreads=%ju namemax=%u owner=%u fsid=[%d, %d] }\n", 2816 (u_int)sp->f_version, (u_int)sp->f_type, (uintmax_t)sp->f_flags, 2817 (uintmax_t)sp->f_bsize, (uintmax_t)sp->f_iosize, 2818 (uintmax_t)sp->f_blocks, (uintmax_t)sp->f_bfree, 2819 (intmax_t)sp->f_bavail, (uintmax_t)sp->f_files, 2820 (intmax_t)sp->f_ffree, (uintmax_t)sp->f_syncwrites, 2821 (uintmax_t)sp->f_asyncwrites, (uintmax_t)sp->f_syncreads, 2822 (uintmax_t)sp->f_asyncreads, (u_int)sp->f_namemax, 2823 (u_int)sp->f_owner, (int)sp->f_fsid.val[0], (int)sp->f_fsid.val[1]); 2824 2825 db_printf(" mnt_cred = { uid=%u ruid=%u", 2826 (u_int)mp->mnt_cred->cr_uid, (u_int)mp->mnt_cred->cr_ruid); 2827 if (mp->mnt_cred->cr_prison != NULL) 2828 db_printf(", jail=%d", mp->mnt_cred->cr_prison->pr_id); 2829 db_printf(" }\n"); 2830 db_printf(" mnt_ref = %d\n", mp->mnt_ref); 2831 db_printf(" mnt_gen = %d\n", mp->mnt_gen); 2832 db_printf(" mnt_nvnodelistsize = %d\n", mp->mnt_nvnodelistsize); 2833 db_printf(" mnt_writeopcount = %d\n", mp->mnt_writeopcount); 2834 db_printf(" mnt_noasync = %u\n", mp->mnt_noasync); 2835 db_printf(" mnt_maxsymlinklen = %d\n", mp->mnt_maxsymlinklen); 2836 db_printf(" mnt_iosize_max = %d\n", mp->mnt_iosize_max); 2837 db_printf(" mnt_hashseed = %u\n", mp->mnt_hashseed); 2838 db_printf(" mnt_markercnt = %d\n", mp->mnt_markercnt); 2839 db_printf(" mnt_holdcnt = %d\n", mp->mnt_holdcnt); 2840 db_printf(" mnt_holdcntwaiters = %d\n", mp->mnt_holdcntwaiters); 2841 db_printf(" mnt_secondary_writes = %d\n", mp->mnt_secondary_writes); 2842 db_printf(" mnt_secondary_accwrites = %d\n", 2843 mp->mnt_secondary_accwrites); 2844 db_printf(" mnt_gjprovider = %s\n", 2845 mp->mnt_gjprovider != NULL ? mp->mnt_gjprovider : "NULL"); 2846 db_printf("\n"); 2847 2848 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) { 2849 if (vp->v_type != VMARKER) { 2850 vn_printf(vp, "vnode "); 2851 if (db_pager_quit) 2852 break; 2853 } 2854 } 2855 } 2856 #endif /* DDB */ 2857 2858 /* 2859 * Fill in a struct xvfsconf based on a struct vfsconf. 2860 */ 2861 static void 2862 vfsconf2x(struct vfsconf *vfsp, struct xvfsconf *xvfsp) 2863 { 2864 2865 strcpy(xvfsp->vfc_name, vfsp->vfc_name); 2866 xvfsp->vfc_typenum = vfsp->vfc_typenum; 2867 xvfsp->vfc_refcount = vfsp->vfc_refcount; 2868 xvfsp->vfc_flags = vfsp->vfc_flags; 2869 /* 2870 * These are unused in userland, we keep them 2871 * to not break binary compatibility. 2872 */ 2873 xvfsp->vfc_vfsops = NULL; 2874 xvfsp->vfc_next = NULL; 2875 } 2876 2877 /* 2878 * Top level filesystem related information gathering. 2879 */ 2880 static int 2881 sysctl_vfs_conflist(SYSCTL_HANDLER_ARGS) 2882 { 2883 struct vfsconf *vfsp; 2884 struct xvfsconf xvfsp; 2885 int error; 2886 2887 error = 0; 2888 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) { 2889 bzero(&xvfsp, sizeof(xvfsp)); 2890 vfsconf2x(vfsp, &xvfsp); 2891 error = SYSCTL_OUT(req, &xvfsp, sizeof xvfsp); 2892 if (error) 2893 break; 2894 } 2895 return (error); 2896 } 2897 2898 SYSCTL_PROC(_vfs, OID_AUTO, conflist, CTLFLAG_RD, NULL, 0, sysctl_vfs_conflist, 2899 "S,xvfsconf", "List of all configured filesystems"); 2900 2901 #ifndef BURN_BRIDGES 2902 static int sysctl_ovfs_conf(SYSCTL_HANDLER_ARGS); 2903 2904 static int 2905 vfs_sysctl(SYSCTL_HANDLER_ARGS) 2906 { 2907 int *name = (int *)arg1 - 1; /* XXX */ 2908 u_int namelen = arg2 + 1; /* XXX */ 2909 struct vfsconf *vfsp; 2910 struct xvfsconf xvfsp; 2911 2912 printf("WARNING: userland calling deprecated sysctl, " 2913 "please rebuild world\n"); 2914 2915 #if 1 || defined(COMPAT_PRELITE2) 2916 /* Resolve ambiguity between VFS_VFSCONF and VFS_GENERIC. */ 2917 if (namelen == 1) 2918 return (sysctl_ovfs_conf(oidp, arg1, arg2, req)); 2919 #endif 2920 2921 switch (name[1]) { 2922 case VFS_MAXTYPENUM: 2923 if (namelen != 2) 2924 return (ENOTDIR); 2925 return (SYSCTL_OUT(req, &maxvfsconf, sizeof(int))); 2926 case VFS_CONF: 2927 if (namelen != 3) 2928 return (ENOTDIR); /* overloaded */ 2929 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) 2930 if (vfsp->vfc_typenum == name[2]) 2931 break; 2932 if (vfsp == NULL) 2933 return (EOPNOTSUPP); 2934 bzero(&xvfsp, sizeof(xvfsp)); 2935 vfsconf2x(vfsp, &xvfsp); 2936 return (SYSCTL_OUT(req, &xvfsp, sizeof(xvfsp))); 2937 } 2938 return (EOPNOTSUPP); 2939 } 2940 2941 static SYSCTL_NODE(_vfs, VFS_GENERIC, generic, CTLFLAG_RD | CTLFLAG_SKIP, 2942 vfs_sysctl, "Generic filesystem"); 2943 2944 #if 1 || defined(COMPAT_PRELITE2) 2945 2946 static int 2947 sysctl_ovfs_conf(SYSCTL_HANDLER_ARGS) 2948 { 2949 int error; 2950 struct vfsconf *vfsp; 2951 struct ovfsconf ovfs; 2952 2953 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) { 2954 bzero(&ovfs, sizeof(ovfs)); 2955 ovfs.vfc_vfsops = vfsp->vfc_vfsops; /* XXX used as flag */ 2956 strcpy(ovfs.vfc_name, vfsp->vfc_name); 2957 ovfs.vfc_index = vfsp->vfc_typenum; 2958 ovfs.vfc_refcount = vfsp->vfc_refcount; 2959 ovfs.vfc_flags = vfsp->vfc_flags; 2960 error = SYSCTL_OUT(req, &ovfs, sizeof ovfs); 2961 if (error) 2962 return error; 2963 } 2964 return 0; 2965 } 2966 2967 #endif /* 1 || COMPAT_PRELITE2 */ 2968 #endif /* !BURN_BRIDGES */ 2969 2970 #define KINFO_VNODESLOP 10 2971 #ifdef notyet 2972 /* 2973 * Dump vnode list (via sysctl). 2974 */ 2975 /* ARGSUSED */ 2976 static int 2977 sysctl_vnode(SYSCTL_HANDLER_ARGS) 2978 { 2979 struct xvnode *xvn; 2980 struct thread *td = req->td; 2981 struct mount *mp; 2982 struct vnode *vp; 2983 int error, len, n; 2984 2985 /* 2986 * Stale numvnodes access is not fatal here. 2987 */ 2988 req->lock = 0; 2989 len = (numvnodes + KINFO_VNODESLOP) * sizeof *xvn; 2990 if (!req->oldptr) 2991 /* Make an estimate */ 2992 return (SYSCTL_OUT(req, 0, len)); 2993 2994 error = sysctl_wire_old_buffer(req, 0); 2995 if (error != 0) 2996 return (error); 2997 xvn = malloc(len, M_TEMP, M_ZERO | M_WAITOK); 2998 n = 0; 2999 mtx_lock(&mountlist_mtx); 3000 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 3001 if (vfs_busy(mp, LK_NOWAIT, &mountlist_mtx, td)) 3002 continue; 3003 MNT_ILOCK(mp); 3004 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) { 3005 if (n == len) 3006 break; 3007 vref(vp); 3008 xvn[n].xv_size = sizeof *xvn; 3009 xvn[n].xv_vnode = vp; 3010 xvn[n].xv_id = 0; /* XXX compat */ 3011 #define XV_COPY(field) xvn[n].xv_##field = vp->v_##field 3012 XV_COPY(usecount); 3013 XV_COPY(writecount); 3014 XV_COPY(holdcnt); 3015 XV_COPY(mount); 3016 XV_COPY(numoutput); 3017 XV_COPY(type); 3018 #undef XV_COPY 3019 xvn[n].xv_flag = vp->v_vflag; 3020 3021 switch (vp->v_type) { 3022 case VREG: 3023 case VDIR: 3024 case VLNK: 3025 break; 3026 case VBLK: 3027 case VCHR: 3028 if (vp->v_rdev == NULL) { 3029 vrele(vp); 3030 continue; 3031 } 3032 xvn[n].xv_dev = dev2udev(vp->v_rdev); 3033 break; 3034 case VSOCK: 3035 xvn[n].xv_socket = vp->v_socket; 3036 break; 3037 case VFIFO: 3038 xvn[n].xv_fifo = vp->v_fifoinfo; 3039 break; 3040 case VNON: 3041 case VBAD: 3042 default: 3043 /* shouldn't happen? */ 3044 vrele(vp); 3045 continue; 3046 } 3047 vrele(vp); 3048 ++n; 3049 } 3050 MNT_IUNLOCK(mp); 3051 mtx_lock(&mountlist_mtx); 3052 vfs_unbusy(mp, td); 3053 if (n == len) 3054 break; 3055 } 3056 mtx_unlock(&mountlist_mtx); 3057 3058 error = SYSCTL_OUT(req, xvn, n * sizeof *xvn); 3059 free(xvn, M_TEMP); 3060 return (error); 3061 } 3062 3063 SYSCTL_PROC(_kern, KERN_VNODE, vnode, CTLTYPE_OPAQUE|CTLFLAG_RD, 3064 0, 0, sysctl_vnode, "S,xvnode", ""); 3065 #endif 3066 3067 /* 3068 * Unmount all filesystems. The list is traversed in reverse order 3069 * of mounting to avoid dependencies. 3070 */ 3071 void 3072 vfs_unmountall(void) 3073 { 3074 struct mount *mp; 3075 struct thread *td; 3076 int error; 3077 3078 KASSERT(curthread != NULL, ("vfs_unmountall: NULL curthread")); 3079 td = curthread; 3080 /* 3081 * Since this only runs when rebooting, it is not interlocked. 3082 */ 3083 while(!TAILQ_EMPTY(&mountlist)) { 3084 mp = TAILQ_LAST(&mountlist, mntlist); 3085 error = dounmount(mp, MNT_FORCE, td); 3086 if (error) { 3087 TAILQ_REMOVE(&mountlist, mp, mnt_list); 3088 /* 3089 * XXX: Due to the way in which we mount the root 3090 * file system off of devfs, devfs will generate a 3091 * "busy" warning when we try to unmount it before 3092 * the root. Don't print a warning as a result in 3093 * order to avoid false positive errors that may 3094 * cause needless upset. 3095 */ 3096 if (strcmp(mp->mnt_vfc->vfc_name, "devfs") != 0) { 3097 printf("unmount of %s failed (", 3098 mp->mnt_stat.f_mntonname); 3099 if (error == EBUSY) 3100 printf("BUSY)\n"); 3101 else 3102 printf("%d)\n", error); 3103 } 3104 } else { 3105 /* The unmount has removed mp from the mountlist */ 3106 } 3107 } 3108 } 3109 3110 /* 3111 * perform msync on all vnodes under a mount point 3112 * the mount point must be locked. 3113 */ 3114 void 3115 vfs_msync(struct mount *mp, int flags) 3116 { 3117 struct vnode *vp, *mvp; 3118 struct vm_object *obj; 3119 3120 MNT_ILOCK(mp); 3121 MNT_VNODE_FOREACH(vp, mp, mvp) { 3122 VI_LOCK(vp); 3123 if ((vp->v_iflag & VI_OBJDIRTY) && 3124 (flags == MNT_WAIT || VOP_ISLOCKED(vp) == 0)) { 3125 MNT_IUNLOCK(mp); 3126 if (!vget(vp, 3127 LK_EXCLUSIVE | LK_RETRY | LK_INTERLOCK, 3128 curthread)) { 3129 if (vp->v_vflag & VV_NOSYNC) { /* unlinked */ 3130 vput(vp); 3131 MNT_ILOCK(mp); 3132 continue; 3133 } 3134 3135 obj = vp->v_object; 3136 if (obj != NULL) { 3137 VM_OBJECT_LOCK(obj); 3138 vm_object_page_clean(obj, 0, 0, 3139 flags == MNT_WAIT ? 3140 OBJPC_SYNC : OBJPC_NOSYNC); 3141 VM_OBJECT_UNLOCK(obj); 3142 } 3143 vput(vp); 3144 } 3145 MNT_ILOCK(mp); 3146 } else 3147 VI_UNLOCK(vp); 3148 } 3149 MNT_IUNLOCK(mp); 3150 } 3151 3152 /* 3153 * Mark a vnode as free, putting it up for recycling. 3154 */ 3155 static void 3156 vfree(struct vnode *vp) 3157 { 3158 3159 CTR1(KTR_VFS, "vfree vp %p", vp); 3160 ASSERT_VI_LOCKED(vp, "vfree"); 3161 mtx_lock(&vnode_free_list_mtx); 3162 VNASSERT(vp->v_op != NULL, vp, ("vfree: vnode already reclaimed.")); 3163 VNASSERT((vp->v_iflag & VI_FREE) == 0, vp, ("vnode already free")); 3164 VNASSERT(VSHOULDFREE(vp), vp, ("vfree: freeing when we shouldn't")); 3165 VNASSERT((vp->v_iflag & VI_DOOMED) == 0, vp, 3166 ("vfree: Freeing doomed vnode")); 3167 if (vp->v_iflag & VI_AGE) { 3168 TAILQ_INSERT_HEAD(&vnode_free_list, vp, v_freelist); 3169 } else { 3170 TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_freelist); 3171 } 3172 freevnodes++; 3173 vp->v_iflag &= ~VI_AGE; 3174 vp->v_iflag |= VI_FREE; 3175 mtx_unlock(&vnode_free_list_mtx); 3176 } 3177 3178 /* 3179 * Opposite of vfree() - mark a vnode as in use. 3180 */ 3181 static void 3182 vbusy(struct vnode *vp) 3183 { 3184 CTR1(KTR_VFS, "vbusy vp %p", vp); 3185 ASSERT_VI_LOCKED(vp, "vbusy"); 3186 VNASSERT((vp->v_iflag & VI_FREE) != 0, vp, ("vnode not free")); 3187 VNASSERT(vp->v_op != NULL, vp, ("vbusy: vnode already reclaimed.")); 3188 3189 mtx_lock(&vnode_free_list_mtx); 3190 TAILQ_REMOVE(&vnode_free_list, vp, v_freelist); 3191 freevnodes--; 3192 vp->v_iflag &= ~(VI_FREE|VI_AGE); 3193 mtx_unlock(&vnode_free_list_mtx); 3194 } 3195 3196 /* 3197 * Initalize per-vnode helper structure to hold poll-related state. 3198 */ 3199 void 3200 v_addpollinfo(struct vnode *vp) 3201 { 3202 struct vpollinfo *vi; 3203 3204 vi = uma_zalloc(vnodepoll_zone, M_WAITOK); 3205 if (vp->v_pollinfo != NULL) { 3206 uma_zfree(vnodepoll_zone, vi); 3207 return; 3208 } 3209 vp->v_pollinfo = vi; 3210 mtx_init(&vp->v_pollinfo->vpi_lock, "vnode pollinfo", NULL, MTX_DEF); 3211 knlist_init(&vp->v_pollinfo->vpi_selinfo.si_note, vp, vfs_knllock, 3212 vfs_knlunlock, vfs_knllocked); 3213 } 3214 3215 /* 3216 * Record a process's interest in events which might happen to 3217 * a vnode. Because poll uses the historic select-style interface 3218 * internally, this routine serves as both the ``check for any 3219 * pending events'' and the ``record my interest in future events'' 3220 * functions. (These are done together, while the lock is held, 3221 * to avoid race conditions.) 3222 */ 3223 int 3224 vn_pollrecord(struct vnode *vp, struct thread *td, int events) 3225 { 3226 3227 if (vp->v_pollinfo == NULL) 3228 v_addpollinfo(vp); 3229 mtx_lock(&vp->v_pollinfo->vpi_lock); 3230 if (vp->v_pollinfo->vpi_revents & events) { 3231 /* 3232 * This leaves events we are not interested 3233 * in available for the other process which 3234 * which presumably had requested them 3235 * (otherwise they would never have been 3236 * recorded). 3237 */ 3238 events &= vp->v_pollinfo->vpi_revents; 3239 vp->v_pollinfo->vpi_revents &= ~events; 3240 3241 mtx_unlock(&vp->v_pollinfo->vpi_lock); 3242 return events; 3243 } 3244 vp->v_pollinfo->vpi_events |= events; 3245 selrecord(td, &vp->v_pollinfo->vpi_selinfo); 3246 mtx_unlock(&vp->v_pollinfo->vpi_lock); 3247 return 0; 3248 } 3249 3250 /* 3251 * Routine to create and manage a filesystem syncer vnode. 3252 */ 3253 #define sync_close ((int (*)(struct vop_close_args *))nullop) 3254 static int sync_fsync(struct vop_fsync_args *); 3255 static int sync_inactive(struct vop_inactive_args *); 3256 static int sync_reclaim(struct vop_reclaim_args *); 3257 3258 static struct vop_vector sync_vnodeops = { 3259 .vop_bypass = VOP_EOPNOTSUPP, 3260 .vop_close = sync_close, /* close */ 3261 .vop_fsync = sync_fsync, /* fsync */ 3262 .vop_inactive = sync_inactive, /* inactive */ 3263 .vop_reclaim = sync_reclaim, /* reclaim */ 3264 .vop_lock1 = vop_stdlock, /* lock */ 3265 .vop_unlock = vop_stdunlock, /* unlock */ 3266 .vop_islocked = vop_stdislocked, /* islocked */ 3267 }; 3268 3269 /* 3270 * Create a new filesystem syncer vnode for the specified mount point. 3271 */ 3272 int 3273 vfs_allocate_syncvnode(struct mount *mp) 3274 { 3275 struct vnode *vp; 3276 struct bufobj *bo; 3277 static long start, incr, next; 3278 int error; 3279 3280 /* Allocate a new vnode */ 3281 if ((error = getnewvnode("syncer", mp, &sync_vnodeops, &vp)) != 0) { 3282 mp->mnt_syncer = NULL; 3283 return (error); 3284 } 3285 vp->v_type = VNON; 3286 error = insmntque(vp, mp); 3287 if (error != 0) 3288 panic("vfs_allocate_syncvnode: insmntque failed"); 3289 /* 3290 * Place the vnode onto the syncer worklist. We attempt to 3291 * scatter them about on the list so that they will go off 3292 * at evenly distributed times even if all the filesystems 3293 * are mounted at once. 3294 */ 3295 next += incr; 3296 if (next == 0 || next > syncer_maxdelay) { 3297 start /= 2; 3298 incr /= 2; 3299 if (start == 0) { 3300 start = syncer_maxdelay / 2; 3301 incr = syncer_maxdelay; 3302 } 3303 next = start; 3304 } 3305 bo = &vp->v_bufobj; 3306 BO_LOCK(bo); 3307 vn_syncer_add_to_worklist(bo, syncdelay > 0 ? next % syncdelay : 0); 3308 /* XXX - vn_syncer_add_to_worklist() also grabs and drops sync_mtx. */ 3309 mtx_lock(&sync_mtx); 3310 sync_vnode_count++; 3311 mtx_unlock(&sync_mtx); 3312 BO_UNLOCK(bo); 3313 mp->mnt_syncer = vp; 3314 return (0); 3315 } 3316 3317 /* 3318 * Do a lazy sync of the filesystem. 3319 */ 3320 static int 3321 sync_fsync(struct vop_fsync_args *ap) 3322 { 3323 struct vnode *syncvp = ap->a_vp; 3324 struct mount *mp = syncvp->v_mount; 3325 struct thread *td = ap->a_td; 3326 int error; 3327 struct bufobj *bo; 3328 3329 /* 3330 * We only need to do something if this is a lazy evaluation. 3331 */ 3332 if (ap->a_waitfor != MNT_LAZY) 3333 return (0); 3334 3335 /* 3336 * Move ourselves to the back of the sync list. 3337 */ 3338 bo = &syncvp->v_bufobj; 3339 BO_LOCK(bo); 3340 vn_syncer_add_to_worklist(bo, syncdelay); 3341 BO_UNLOCK(bo); 3342 3343 /* 3344 * Walk the list of vnodes pushing all that are dirty and 3345 * not already on the sync list. 3346 */ 3347 mtx_lock(&mountlist_mtx); 3348 if (vfs_busy(mp, LK_EXCLUSIVE | LK_NOWAIT, &mountlist_mtx, td) != 0) { 3349 mtx_unlock(&mountlist_mtx); 3350 return (0); 3351 } 3352 if (vn_start_write(NULL, &mp, V_NOWAIT) != 0) { 3353 vfs_unbusy(mp, td); 3354 return (0); 3355 } 3356 MNT_ILOCK(mp); 3357 mp->mnt_noasync++; 3358 mp->mnt_kern_flag &= ~MNTK_ASYNC; 3359 MNT_IUNLOCK(mp); 3360 vfs_msync(mp, MNT_NOWAIT); 3361 error = VFS_SYNC(mp, MNT_LAZY, td); 3362 MNT_ILOCK(mp); 3363 mp->mnt_noasync--; 3364 if ((mp->mnt_flag & MNT_ASYNC) != 0 && mp->mnt_noasync == 0) 3365 mp->mnt_kern_flag |= MNTK_ASYNC; 3366 MNT_IUNLOCK(mp); 3367 vn_finished_write(mp); 3368 vfs_unbusy(mp, td); 3369 return (error); 3370 } 3371 3372 /* 3373 * The syncer vnode is no referenced. 3374 */ 3375 static int 3376 sync_inactive(struct vop_inactive_args *ap) 3377 { 3378 3379 vgone(ap->a_vp); 3380 return (0); 3381 } 3382 3383 /* 3384 * The syncer vnode is no longer needed and is being decommissioned. 3385 * 3386 * Modifications to the worklist must be protected by sync_mtx. 3387 */ 3388 static int 3389 sync_reclaim(struct vop_reclaim_args *ap) 3390 { 3391 struct vnode *vp = ap->a_vp; 3392 struct bufobj *bo; 3393 3394 bo = &vp->v_bufobj; 3395 BO_LOCK(bo); 3396 vp->v_mount->mnt_syncer = NULL; 3397 if (bo->bo_flag & BO_ONWORKLST) { 3398 mtx_lock(&sync_mtx); 3399 LIST_REMOVE(bo, bo_synclist); 3400 syncer_worklist_len--; 3401 sync_vnode_count--; 3402 mtx_unlock(&sync_mtx); 3403 bo->bo_flag &= ~BO_ONWORKLST; 3404 } 3405 BO_UNLOCK(bo); 3406 3407 return (0); 3408 } 3409 3410 /* 3411 * Check if vnode represents a disk device 3412 */ 3413 int 3414 vn_isdisk(struct vnode *vp, int *errp) 3415 { 3416 int error; 3417 3418 error = 0; 3419 dev_lock(); 3420 if (vp->v_type != VCHR) 3421 error = ENOTBLK; 3422 else if (vp->v_rdev == NULL) 3423 error = ENXIO; 3424 else if (vp->v_rdev->si_devsw == NULL) 3425 error = ENXIO; 3426 else if (!(vp->v_rdev->si_devsw->d_flags & D_DISK)) 3427 error = ENOTBLK; 3428 dev_unlock(); 3429 if (errp != NULL) 3430 *errp = error; 3431 return (error == 0); 3432 } 3433 3434 /* 3435 * Common filesystem object access control check routine. Accepts a 3436 * vnode's type, "mode", uid and gid, requested access mode, credentials, 3437 * and optional call-by-reference privused argument allowing vaccess() 3438 * to indicate to the caller whether privilege was used to satisfy the 3439 * request (obsoleted). Returns 0 on success, or an errno on failure. 3440 * 3441 * The ifdef'd CAPABILITIES version is here for reference, but is not 3442 * actually used. 3443 */ 3444 int 3445 vaccess(enum vtype type, mode_t file_mode, uid_t file_uid, gid_t file_gid, 3446 mode_t acc_mode, struct ucred *cred, int *privused) 3447 { 3448 mode_t dac_granted; 3449 mode_t priv_granted; 3450 3451 /* 3452 * Look for a normal, non-privileged way to access the file/directory 3453 * as requested. If it exists, go with that. 3454 */ 3455 3456 if (privused != NULL) 3457 *privused = 0; 3458 3459 dac_granted = 0; 3460 3461 /* Check the owner. */ 3462 if (cred->cr_uid == file_uid) { 3463 dac_granted |= VADMIN; 3464 if (file_mode & S_IXUSR) 3465 dac_granted |= VEXEC; 3466 if (file_mode & S_IRUSR) 3467 dac_granted |= VREAD; 3468 if (file_mode & S_IWUSR) 3469 dac_granted |= (VWRITE | VAPPEND); 3470 3471 if ((acc_mode & dac_granted) == acc_mode) 3472 return (0); 3473 3474 goto privcheck; 3475 } 3476 3477 /* Otherwise, check the groups (first match) */ 3478 if (groupmember(file_gid, cred)) { 3479 if (file_mode & S_IXGRP) 3480 dac_granted |= VEXEC; 3481 if (file_mode & S_IRGRP) 3482 dac_granted |= VREAD; 3483 if (file_mode & S_IWGRP) 3484 dac_granted |= (VWRITE | VAPPEND); 3485 3486 if ((acc_mode & dac_granted) == acc_mode) 3487 return (0); 3488 3489 goto privcheck; 3490 } 3491 3492 /* Otherwise, check everyone else. */ 3493 if (file_mode & S_IXOTH) 3494 dac_granted |= VEXEC; 3495 if (file_mode & S_IROTH) 3496 dac_granted |= VREAD; 3497 if (file_mode & S_IWOTH) 3498 dac_granted |= (VWRITE | VAPPEND); 3499 if ((acc_mode & dac_granted) == acc_mode) 3500 return (0); 3501 3502 privcheck: 3503 /* 3504 * Build a privilege mask to determine if the set of privileges 3505 * satisfies the requirements when combined with the granted mask 3506 * from above. For each privilege, if the privilege is required, 3507 * bitwise or the request type onto the priv_granted mask. 3508 */ 3509 priv_granted = 0; 3510 3511 if (type == VDIR) { 3512 /* 3513 * For directories, use PRIV_VFS_LOOKUP to satisfy VEXEC 3514 * requests, instead of PRIV_VFS_EXEC. 3515 */ 3516 if ((acc_mode & VEXEC) && ((dac_granted & VEXEC) == 0) && 3517 !priv_check_cred(cred, PRIV_VFS_LOOKUP, 0)) 3518 priv_granted |= VEXEC; 3519 } else { 3520 if ((acc_mode & VEXEC) && ((dac_granted & VEXEC) == 0) && 3521 !priv_check_cred(cred, PRIV_VFS_EXEC, 0)) 3522 priv_granted |= VEXEC; 3523 } 3524 3525 if ((acc_mode & VREAD) && ((dac_granted & VREAD) == 0) && 3526 !priv_check_cred(cred, PRIV_VFS_READ, 0)) 3527 priv_granted |= VREAD; 3528 3529 if ((acc_mode & VWRITE) && ((dac_granted & VWRITE) == 0) && 3530 !priv_check_cred(cred, PRIV_VFS_WRITE, 0)) 3531 priv_granted |= (VWRITE | VAPPEND); 3532 3533 if ((acc_mode & VADMIN) && ((dac_granted & VADMIN) == 0) && 3534 !priv_check_cred(cred, PRIV_VFS_ADMIN, 0)) 3535 priv_granted |= VADMIN; 3536 3537 if ((acc_mode & (priv_granted | dac_granted)) == acc_mode) { 3538 /* XXX audit: privilege used */ 3539 if (privused != NULL) 3540 *privused = 1; 3541 return (0); 3542 } 3543 3544 return ((acc_mode & VADMIN) ? EPERM : EACCES); 3545 } 3546 3547 /* 3548 * Credential check based on process requesting service, and per-attribute 3549 * permissions. 3550 */ 3551 int 3552 extattr_check_cred(struct vnode *vp, int attrnamespace, struct ucred *cred, 3553 struct thread *td, int access) 3554 { 3555 3556 /* 3557 * Kernel-invoked always succeeds. 3558 */ 3559 if (cred == NOCRED) 3560 return (0); 3561 3562 /* 3563 * Do not allow privileged processes in jail to directly manipulate 3564 * system attributes. 3565 */ 3566 switch (attrnamespace) { 3567 case EXTATTR_NAMESPACE_SYSTEM: 3568 /* Potentially should be: return (EPERM); */ 3569 return (priv_check_cred(cred, PRIV_VFS_EXTATTR_SYSTEM, 0)); 3570 case EXTATTR_NAMESPACE_USER: 3571 return (VOP_ACCESS(vp, access, cred, td)); 3572 default: 3573 return (EPERM); 3574 } 3575 } 3576 3577 #ifdef DEBUG_VFS_LOCKS 3578 /* 3579 * This only exists to supress warnings from unlocked specfs accesses. It is 3580 * no longer ok to have an unlocked VFS. 3581 */ 3582 #define IGNORE_LOCK(vp) ((vp)->v_type == VCHR || (vp)->v_type == VBAD) 3583 3584 int vfs_badlock_ddb = 1; /* Drop into debugger on violation. */ 3585 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_ddb, CTLFLAG_RW, &vfs_badlock_ddb, 0, ""); 3586 3587 int vfs_badlock_mutex = 1; /* Check for interlock across VOPs. */ 3588 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_mutex, CTLFLAG_RW, &vfs_badlock_mutex, 0, ""); 3589 3590 int vfs_badlock_print = 1; /* Print lock violations. */ 3591 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_print, CTLFLAG_RW, &vfs_badlock_print, 0, ""); 3592 3593 #ifdef KDB 3594 int vfs_badlock_backtrace = 1; /* Print backtrace at lock violations. */ 3595 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_backtrace, CTLFLAG_RW, &vfs_badlock_backtrace, 0, ""); 3596 #endif 3597 3598 static void 3599 vfs_badlock(const char *msg, const char *str, struct vnode *vp) 3600 { 3601 3602 #ifdef KDB 3603 if (vfs_badlock_backtrace) 3604 kdb_backtrace(); 3605 #endif 3606 if (vfs_badlock_print) 3607 printf("%s: %p %s\n", str, (void *)vp, msg); 3608 if (vfs_badlock_ddb) 3609 kdb_enter(KDB_WHY_VFSLOCK, "lock violation"); 3610 } 3611 3612 void 3613 assert_vi_locked(struct vnode *vp, const char *str) 3614 { 3615 3616 if (vfs_badlock_mutex && !mtx_owned(VI_MTX(vp))) 3617 vfs_badlock("interlock is not locked but should be", str, vp); 3618 } 3619 3620 void 3621 assert_vi_unlocked(struct vnode *vp, const char *str) 3622 { 3623 3624 if (vfs_badlock_mutex && mtx_owned(VI_MTX(vp))) 3625 vfs_badlock("interlock is locked but should not be", str, vp); 3626 } 3627 3628 void 3629 assert_vop_locked(struct vnode *vp, const char *str) 3630 { 3631 3632 if (vp && !IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) == 0) 3633 vfs_badlock("is not locked but should be", str, vp); 3634 } 3635 3636 void 3637 assert_vop_unlocked(struct vnode *vp, const char *str) 3638 { 3639 3640 if (vp && !IGNORE_LOCK(vp) && 3641 VOP_ISLOCKED(vp) == LK_EXCLUSIVE) 3642 vfs_badlock("is locked but should not be", str, vp); 3643 } 3644 3645 void 3646 assert_vop_elocked(struct vnode *vp, const char *str) 3647 { 3648 3649 if (vp && !IGNORE_LOCK(vp) && 3650 VOP_ISLOCKED(vp) != LK_EXCLUSIVE) 3651 vfs_badlock("is not exclusive locked but should be", str, vp); 3652 } 3653 3654 #if 0 3655 void 3656 assert_vop_elocked_other(struct vnode *vp, const char *str) 3657 { 3658 3659 if (vp && !IGNORE_LOCK(vp) && 3660 VOP_ISLOCKED(vp) != LK_EXCLOTHER) 3661 vfs_badlock("is not exclusive locked by another thread", 3662 str, vp); 3663 } 3664 3665 void 3666 assert_vop_slocked(struct vnode *vp, const char *str) 3667 { 3668 3669 if (vp && !IGNORE_LOCK(vp) && 3670 VOP_ISLOCKED(vp) != LK_SHARED) 3671 vfs_badlock("is not locked shared but should be", str, vp); 3672 } 3673 #endif /* 0 */ 3674 #endif /* DEBUG_VFS_LOCKS */ 3675 3676 void 3677 vop_rename_pre(void *ap) 3678 { 3679 struct vop_rename_args *a = ap; 3680 3681 #ifdef DEBUG_VFS_LOCKS 3682 if (a->a_tvp) 3683 ASSERT_VI_UNLOCKED(a->a_tvp, "VOP_RENAME"); 3684 ASSERT_VI_UNLOCKED(a->a_tdvp, "VOP_RENAME"); 3685 ASSERT_VI_UNLOCKED(a->a_fvp, "VOP_RENAME"); 3686 ASSERT_VI_UNLOCKED(a->a_fdvp, "VOP_RENAME"); 3687 3688 /* Check the source (from). */ 3689 if (a->a_tdvp != a->a_fdvp && a->a_tvp != a->a_fdvp) 3690 ASSERT_VOP_UNLOCKED(a->a_fdvp, "vop_rename: fdvp locked"); 3691 if (a->a_tvp != a->a_fvp) 3692 ASSERT_VOP_UNLOCKED(a->a_fvp, "vop_rename: fvp locked"); 3693 3694 /* Check the target. */ 3695 if (a->a_tvp) 3696 ASSERT_VOP_LOCKED(a->a_tvp, "vop_rename: tvp not locked"); 3697 ASSERT_VOP_LOCKED(a->a_tdvp, "vop_rename: tdvp not locked"); 3698 #endif 3699 if (a->a_tdvp != a->a_fdvp) 3700 vhold(a->a_fdvp); 3701 if (a->a_tvp != a->a_fvp) 3702 vhold(a->a_fvp); 3703 vhold(a->a_tdvp); 3704 if (a->a_tvp) 3705 vhold(a->a_tvp); 3706 } 3707 3708 void 3709 vop_strategy_pre(void *ap) 3710 { 3711 #ifdef DEBUG_VFS_LOCKS 3712 struct vop_strategy_args *a; 3713 struct buf *bp; 3714 3715 a = ap; 3716 bp = a->a_bp; 3717 3718 /* 3719 * Cluster ops lock their component buffers but not the IO container. 3720 */ 3721 if ((bp->b_flags & B_CLUSTER) != 0) 3722 return; 3723 3724 if (!BUF_ISLOCKED(bp)) { 3725 if (vfs_badlock_print) 3726 printf( 3727 "VOP_STRATEGY: bp is not locked but should be\n"); 3728 if (vfs_badlock_ddb) 3729 kdb_enter(KDB_WHY_VFSLOCK, "lock violation"); 3730 } 3731 #endif 3732 } 3733 3734 void 3735 vop_lookup_pre(void *ap) 3736 { 3737 #ifdef DEBUG_VFS_LOCKS 3738 struct vop_lookup_args *a; 3739 struct vnode *dvp; 3740 3741 a = ap; 3742 dvp = a->a_dvp; 3743 ASSERT_VI_UNLOCKED(dvp, "VOP_LOOKUP"); 3744 ASSERT_VOP_LOCKED(dvp, "VOP_LOOKUP"); 3745 #endif 3746 } 3747 3748 void 3749 vop_lookup_post(void *ap, int rc) 3750 { 3751 #ifdef DEBUG_VFS_LOCKS 3752 struct vop_lookup_args *a; 3753 struct vnode *dvp; 3754 struct vnode *vp; 3755 3756 a = ap; 3757 dvp = a->a_dvp; 3758 vp = *(a->a_vpp); 3759 3760 ASSERT_VI_UNLOCKED(dvp, "VOP_LOOKUP"); 3761 ASSERT_VOP_LOCKED(dvp, "VOP_LOOKUP"); 3762 3763 if (!rc) 3764 ASSERT_VOP_LOCKED(vp, "VOP_LOOKUP (child)"); 3765 #endif 3766 } 3767 3768 void 3769 vop_lock_pre(void *ap) 3770 { 3771 #ifdef DEBUG_VFS_LOCKS 3772 struct vop_lock1_args *a = ap; 3773 3774 if ((a->a_flags & LK_INTERLOCK) == 0) 3775 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_LOCK"); 3776 else 3777 ASSERT_VI_LOCKED(a->a_vp, "VOP_LOCK"); 3778 #endif 3779 } 3780 3781 void 3782 vop_lock_post(void *ap, int rc) 3783 { 3784 #ifdef DEBUG_VFS_LOCKS 3785 struct vop_lock1_args *a = ap; 3786 3787 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_LOCK"); 3788 if (rc == 0) 3789 ASSERT_VOP_LOCKED(a->a_vp, "VOP_LOCK"); 3790 #endif 3791 } 3792 3793 void 3794 vop_unlock_pre(void *ap) 3795 { 3796 #ifdef DEBUG_VFS_LOCKS 3797 struct vop_unlock_args *a = ap; 3798 3799 if (a->a_flags & LK_INTERLOCK) 3800 ASSERT_VI_LOCKED(a->a_vp, "VOP_UNLOCK"); 3801 ASSERT_VOP_LOCKED(a->a_vp, "VOP_UNLOCK"); 3802 #endif 3803 } 3804 3805 void 3806 vop_unlock_post(void *ap, int rc) 3807 { 3808 #ifdef DEBUG_VFS_LOCKS 3809 struct vop_unlock_args *a = ap; 3810 3811 if (a->a_flags & LK_INTERLOCK) 3812 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_UNLOCK"); 3813 #endif 3814 } 3815 3816 void 3817 vop_create_post(void *ap, int rc) 3818 { 3819 struct vop_create_args *a = ap; 3820 3821 if (!rc) 3822 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 3823 } 3824 3825 void 3826 vop_link_post(void *ap, int rc) 3827 { 3828 struct vop_link_args *a = ap; 3829 3830 if (!rc) { 3831 VFS_KNOTE_LOCKED(a->a_vp, NOTE_LINK); 3832 VFS_KNOTE_LOCKED(a->a_tdvp, NOTE_WRITE); 3833 } 3834 } 3835 3836 void 3837 vop_mkdir_post(void *ap, int rc) 3838 { 3839 struct vop_mkdir_args *a = ap; 3840 3841 if (!rc) 3842 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE | NOTE_LINK); 3843 } 3844 3845 void 3846 vop_mknod_post(void *ap, int rc) 3847 { 3848 struct vop_mknod_args *a = ap; 3849 3850 if (!rc) 3851 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 3852 } 3853 3854 void 3855 vop_remove_post(void *ap, int rc) 3856 { 3857 struct vop_remove_args *a = ap; 3858 3859 if (!rc) { 3860 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 3861 VFS_KNOTE_LOCKED(a->a_vp, NOTE_DELETE); 3862 } 3863 } 3864 3865 void 3866 vop_rename_post(void *ap, int rc) 3867 { 3868 struct vop_rename_args *a = ap; 3869 3870 if (!rc) { 3871 VFS_KNOTE_UNLOCKED(a->a_fdvp, NOTE_WRITE); 3872 VFS_KNOTE_UNLOCKED(a->a_tdvp, NOTE_WRITE); 3873 VFS_KNOTE_UNLOCKED(a->a_fvp, NOTE_RENAME); 3874 if (a->a_tvp) 3875 VFS_KNOTE_UNLOCKED(a->a_tvp, NOTE_DELETE); 3876 } 3877 if (a->a_tdvp != a->a_fdvp) 3878 vdrop(a->a_fdvp); 3879 if (a->a_tvp != a->a_fvp) 3880 vdrop(a->a_fvp); 3881 vdrop(a->a_tdvp); 3882 if (a->a_tvp) 3883 vdrop(a->a_tvp); 3884 } 3885 3886 void 3887 vop_rmdir_post(void *ap, int rc) 3888 { 3889 struct vop_rmdir_args *a = ap; 3890 3891 if (!rc) { 3892 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE | NOTE_LINK); 3893 VFS_KNOTE_LOCKED(a->a_vp, NOTE_DELETE); 3894 } 3895 } 3896 3897 void 3898 vop_setattr_post(void *ap, int rc) 3899 { 3900 struct vop_setattr_args *a = ap; 3901 3902 if (!rc) 3903 VFS_KNOTE_LOCKED(a->a_vp, NOTE_ATTRIB); 3904 } 3905 3906 void 3907 vop_symlink_post(void *ap, int rc) 3908 { 3909 struct vop_symlink_args *a = ap; 3910 3911 if (!rc) 3912 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 3913 } 3914 3915 static struct knlist fs_knlist; 3916 3917 static void 3918 vfs_event_init(void *arg) 3919 { 3920 knlist_init(&fs_knlist, NULL, NULL, NULL, NULL); 3921 } 3922 /* XXX - correct order? */ 3923 SYSINIT(vfs_knlist, SI_SUB_VFS, SI_ORDER_ANY, vfs_event_init, NULL); 3924 3925 void 3926 vfs_event_signal(fsid_t *fsid, u_int32_t event, intptr_t data __unused) 3927 { 3928 3929 KNOTE_UNLOCKED(&fs_knlist, event); 3930 } 3931 3932 static int filt_fsattach(struct knote *kn); 3933 static void filt_fsdetach(struct knote *kn); 3934 static int filt_fsevent(struct knote *kn, long hint); 3935 3936 struct filterops fs_filtops = 3937 { 0, filt_fsattach, filt_fsdetach, filt_fsevent }; 3938 3939 static int 3940 filt_fsattach(struct knote *kn) 3941 { 3942 3943 kn->kn_flags |= EV_CLEAR; 3944 knlist_add(&fs_knlist, kn, 0); 3945 return (0); 3946 } 3947 3948 static void 3949 filt_fsdetach(struct knote *kn) 3950 { 3951 3952 knlist_remove(&fs_knlist, kn, 0); 3953 } 3954 3955 static int 3956 filt_fsevent(struct knote *kn, long hint) 3957 { 3958 3959 kn->kn_fflags |= hint; 3960 return (kn->kn_fflags != 0); 3961 } 3962 3963 static int 3964 sysctl_vfs_ctl(SYSCTL_HANDLER_ARGS) 3965 { 3966 struct vfsidctl vc; 3967 int error; 3968 struct mount *mp; 3969 3970 error = SYSCTL_IN(req, &vc, sizeof(vc)); 3971 if (error) 3972 return (error); 3973 if (vc.vc_vers != VFS_CTL_VERS1) 3974 return (EINVAL); 3975 mp = vfs_getvfs(&vc.vc_fsid); 3976 if (mp == NULL) 3977 return (ENOENT); 3978 /* ensure that a specific sysctl goes to the right filesystem. */ 3979 if (strcmp(vc.vc_fstypename, "*") != 0 && 3980 strcmp(vc.vc_fstypename, mp->mnt_vfc->vfc_name) != 0) { 3981 vfs_rel(mp); 3982 return (EINVAL); 3983 } 3984 VCTLTOREQ(&vc, req); 3985 error = VFS_SYSCTL(mp, vc.vc_op, req); 3986 vfs_rel(mp); 3987 return (error); 3988 } 3989 3990 SYSCTL_PROC(_vfs, OID_AUTO, ctl, CTLFLAG_WR, NULL, 0, sysctl_vfs_ctl, "", 3991 "Sysctl by fsid"); 3992 3993 /* 3994 * Function to initialize a va_filerev field sensibly. 3995 * XXX: Wouldn't a random number make a lot more sense ?? 3996 */ 3997 u_quad_t 3998 init_va_filerev(void) 3999 { 4000 struct bintime bt; 4001 4002 getbinuptime(&bt); 4003 return (((u_quad_t)bt.sec << 32LL) | (bt.frac >> 32LL)); 4004 } 4005 4006 static int filt_vfsread(struct knote *kn, long hint); 4007 static int filt_vfswrite(struct knote *kn, long hint); 4008 static int filt_vfsvnode(struct knote *kn, long hint); 4009 static void filt_vfsdetach(struct knote *kn); 4010 static struct filterops vfsread_filtops = 4011 { 1, NULL, filt_vfsdetach, filt_vfsread }; 4012 static struct filterops vfswrite_filtops = 4013 { 1, NULL, filt_vfsdetach, filt_vfswrite }; 4014 static struct filterops vfsvnode_filtops = 4015 { 1, NULL, filt_vfsdetach, filt_vfsvnode }; 4016 4017 static void 4018 vfs_knllock(void *arg) 4019 { 4020 struct vnode *vp = arg; 4021 4022 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 4023 } 4024 4025 static void 4026 vfs_knlunlock(void *arg) 4027 { 4028 struct vnode *vp = arg; 4029 4030 VOP_UNLOCK(vp, 0); 4031 } 4032 4033 static int 4034 vfs_knllocked(void *arg) 4035 { 4036 struct vnode *vp = arg; 4037 4038 return (VOP_ISLOCKED(vp) == LK_EXCLUSIVE); 4039 } 4040 4041 int 4042 vfs_kqfilter(struct vop_kqfilter_args *ap) 4043 { 4044 struct vnode *vp = ap->a_vp; 4045 struct knote *kn = ap->a_kn; 4046 struct knlist *knl; 4047 4048 switch (kn->kn_filter) { 4049 case EVFILT_READ: 4050 kn->kn_fop = &vfsread_filtops; 4051 break; 4052 case EVFILT_WRITE: 4053 kn->kn_fop = &vfswrite_filtops; 4054 break; 4055 case EVFILT_VNODE: 4056 kn->kn_fop = &vfsvnode_filtops; 4057 break; 4058 default: 4059 return (EINVAL); 4060 } 4061 4062 kn->kn_hook = (caddr_t)vp; 4063 4064 if (vp->v_pollinfo == NULL) 4065 v_addpollinfo(vp); 4066 if (vp->v_pollinfo == NULL) 4067 return (ENOMEM); 4068 knl = &vp->v_pollinfo->vpi_selinfo.si_note; 4069 knlist_add(knl, kn, 0); 4070 4071 return (0); 4072 } 4073 4074 /* 4075 * Detach knote from vnode 4076 */ 4077 static void 4078 filt_vfsdetach(struct knote *kn) 4079 { 4080 struct vnode *vp = (struct vnode *)kn->kn_hook; 4081 4082 KASSERT(vp->v_pollinfo != NULL, ("Missing v_pollinfo")); 4083 knlist_remove(&vp->v_pollinfo->vpi_selinfo.si_note, kn, 0); 4084 } 4085 4086 /*ARGSUSED*/ 4087 static int 4088 filt_vfsread(struct knote *kn, long hint) 4089 { 4090 struct vnode *vp = (struct vnode *)kn->kn_hook; 4091 struct vattr va; 4092 4093 /* 4094 * filesystem is gone, so set the EOF flag and schedule 4095 * the knote for deletion. 4096 */ 4097 if (hint == NOTE_REVOKE) { 4098 kn->kn_flags |= (EV_EOF | EV_ONESHOT); 4099 return (1); 4100 } 4101 4102 if (VOP_GETATTR(vp, &va, curthread->td_ucred, curthread)) 4103 return (0); 4104 4105 kn->kn_data = va.va_size - kn->kn_fp->f_offset; 4106 return (kn->kn_data != 0); 4107 } 4108 4109 /*ARGSUSED*/ 4110 static int 4111 filt_vfswrite(struct knote *kn, long hint) 4112 { 4113 /* 4114 * filesystem is gone, so set the EOF flag and schedule 4115 * the knote for deletion. 4116 */ 4117 if (hint == NOTE_REVOKE) 4118 kn->kn_flags |= (EV_EOF | EV_ONESHOT); 4119 4120 kn->kn_data = 0; 4121 return (1); 4122 } 4123 4124 static int 4125 filt_vfsvnode(struct knote *kn, long hint) 4126 { 4127 if (kn->kn_sfflags & hint) 4128 kn->kn_fflags |= hint; 4129 if (hint == NOTE_REVOKE) { 4130 kn->kn_flags |= EV_EOF; 4131 return (1); 4132 } 4133 return (kn->kn_fflags != 0); 4134 } 4135 4136 int 4137 vfs_read_dirent(struct vop_readdir_args *ap, struct dirent *dp, off_t off) 4138 { 4139 int error; 4140 4141 if (dp->d_reclen > ap->a_uio->uio_resid) 4142 return (ENAMETOOLONG); 4143 error = uiomove(dp, dp->d_reclen, ap->a_uio); 4144 if (error) { 4145 if (ap->a_ncookies != NULL) { 4146 if (ap->a_cookies != NULL) 4147 free(ap->a_cookies, M_TEMP); 4148 ap->a_cookies = NULL; 4149 *ap->a_ncookies = 0; 4150 } 4151 return (error); 4152 } 4153 if (ap->a_ncookies == NULL) 4154 return (0); 4155 4156 KASSERT(ap->a_cookies, 4157 ("NULL ap->a_cookies value with non-NULL ap->a_ncookies!")); 4158 4159 *ap->a_cookies = realloc(*ap->a_cookies, 4160 (*ap->a_ncookies + 1) * sizeof(u_long), M_TEMP, M_WAITOK | M_ZERO); 4161 (*ap->a_cookies)[*ap->a_ncookies] = off; 4162 return (0); 4163 } 4164 4165 /* 4166 * Mark for update the access time of the file if the filesystem 4167 * supports VA_MARK_ATIME. This functionality is used by execve 4168 * and mmap, so we want to avoid the synchronous I/O implied by 4169 * directly setting va_atime for the sake of efficiency. 4170 */ 4171 void 4172 vfs_mark_atime(struct vnode *vp, struct thread *td) 4173 { 4174 struct vattr atimeattr; 4175 4176 if ((vp->v_mount->mnt_flag & (MNT_NOATIME | MNT_RDONLY)) == 0) { 4177 VATTR_NULL(&atimeattr); 4178 atimeattr.va_vaflags |= VA_MARK_ATIME; 4179 (void)VOP_SETATTR(vp, &atimeattr, td->td_ucred, td); 4180 } 4181 } 4182