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/condvar.h> 52 #include <sys/conf.h> 53 #include <sys/dirent.h> 54 #include <sys/event.h> 55 #include <sys/eventhandler.h> 56 #include <sys/extattr.h> 57 #include <sys/file.h> 58 #include <sys/fcntl.h> 59 #include <sys/jail.h> 60 #include <sys/kdb.h> 61 #include <sys/kernel.h> 62 #include <sys/kthread.h> 63 #include <sys/lockf.h> 64 #include <sys/malloc.h> 65 #include <sys/mount.h> 66 #include <sys/namei.h> 67 #include <sys/priv.h> 68 #include <sys/reboot.h> 69 #include <sys/sleepqueue.h> 70 #include <sys/stat.h> 71 #include <sys/sysctl.h> 72 #include <sys/syslog.h> 73 #include <sys/vmmeter.h> 74 #include <sys/vnode.h> 75 76 #include <machine/stdarg.h> 77 78 #include <security/mac/mac_framework.h> 79 80 #include <vm/vm.h> 81 #include <vm/vm_object.h> 82 #include <vm/vm_extern.h> 83 #include <vm/pmap.h> 84 #include <vm/vm_map.h> 85 #include <vm/vm_page.h> 86 #include <vm/vm_kern.h> 87 #include <vm/uma.h> 88 89 #ifdef DDB 90 #include <ddb/ddb.h> 91 #endif 92 93 #define WI_MPSAFEQ 0 94 #define WI_GIANTQ 1 95 96 static MALLOC_DEFINE(M_NETADDR, "subr_export_host", "Export host address structure"); 97 98 static void delmntque(struct vnode *vp); 99 static int flushbuflist(struct bufv *bufv, int flags, struct bufobj *bo, 100 int slpflag, int slptimeo); 101 static void syncer_shutdown(void *arg, int howto); 102 static int vtryrecycle(struct vnode *vp); 103 static void vbusy(struct vnode *vp); 104 static void vinactive(struct vnode *, struct thread *); 105 static void v_incr_usecount(struct vnode *); 106 static void v_decr_usecount(struct vnode *); 107 static void v_decr_useonly(struct vnode *); 108 static void v_upgrade_usecount(struct vnode *); 109 static void vfree(struct vnode *); 110 static void vnlru_free(int); 111 static void vdestroy(struct vnode *); 112 static void vgonel(struct vnode *); 113 static void vfs_knllock(void *arg); 114 static void vfs_knlunlock(void *arg); 115 static int vfs_knllocked(void *arg); 116 117 118 /* 119 * Enable Giant pushdown based on whether or not the vm is mpsafe in this 120 * build. Without mpsafevm the buffer cache can not run Giant free. 121 */ 122 int mpsafe_vfs = 1; 123 TUNABLE_INT("debug.mpsafevfs", &mpsafe_vfs); 124 SYSCTL_INT(_debug, OID_AUTO, mpsafevfs, CTLFLAG_RD, &mpsafe_vfs, 0, 125 "MPSAFE VFS"); 126 127 /* 128 * Number of vnodes in existence. Increased whenever getnewvnode() 129 * allocates a new vnode, decreased on vdestroy() called on VI_DOOMed 130 * vnode. 131 */ 132 static unsigned long numvnodes; 133 134 SYSCTL_LONG(_vfs, OID_AUTO, numvnodes, CTLFLAG_RD, &numvnodes, 0, ""); 135 136 /* 137 * Conversion tables for conversion from vnode types to inode formats 138 * and back. 139 */ 140 enum vtype iftovt_tab[16] = { 141 VNON, VFIFO, VCHR, VNON, VDIR, VNON, VBLK, VNON, 142 VREG, VNON, VLNK, VNON, VSOCK, VNON, VNON, VBAD, 143 }; 144 int vttoif_tab[10] = { 145 0, S_IFREG, S_IFDIR, S_IFBLK, S_IFCHR, S_IFLNK, 146 S_IFSOCK, S_IFIFO, S_IFMT, S_IFMT 147 }; 148 149 /* 150 * List of vnodes that are ready for recycling. 151 */ 152 static TAILQ_HEAD(freelst, vnode) vnode_free_list; 153 154 /* 155 * Free vnode target. Free vnodes may simply be files which have been stat'd 156 * but not read. This is somewhat common, and a small cache of such files 157 * should be kept to avoid recreation costs. 158 */ 159 static u_long wantfreevnodes; 160 SYSCTL_LONG(_vfs, OID_AUTO, wantfreevnodes, CTLFLAG_RW, &wantfreevnodes, 0, ""); 161 /* Number of vnodes in the free list. */ 162 static u_long freevnodes; 163 SYSCTL_LONG(_vfs, OID_AUTO, freevnodes, CTLFLAG_RD, &freevnodes, 0, ""); 164 165 /* 166 * Various variables used for debugging the new implementation of 167 * reassignbuf(). 168 * XXX these are probably of (very) limited utility now. 169 */ 170 static int reassignbufcalls; 171 SYSCTL_INT(_vfs, OID_AUTO, reassignbufcalls, CTLFLAG_RW, &reassignbufcalls, 0, ""); 172 173 /* 174 * Cache for the mount type id assigned to NFS. This is used for 175 * special checks in nfs/nfs_nqlease.c and vm/vnode_pager.c. 176 */ 177 int nfs_mount_type = -1; 178 179 /* To keep more than one thread at a time from running vfs_getnewfsid */ 180 static struct mtx mntid_mtx; 181 182 /* 183 * Lock for any access to the following: 184 * vnode_free_list 185 * numvnodes 186 * freevnodes 187 */ 188 static struct mtx vnode_free_list_mtx; 189 190 /* Publicly exported FS */ 191 struct nfs_public nfs_pub; 192 193 /* Zone for allocation of new vnodes - used exclusively by getnewvnode() */ 194 static uma_zone_t vnode_zone; 195 static uma_zone_t vnodepoll_zone; 196 197 /* Set to 1 to print out reclaim of active vnodes */ 198 int prtactive; 199 200 /* 201 * The workitem queue. 202 * 203 * It is useful to delay writes of file data and filesystem metadata 204 * for tens of seconds so that quickly created and deleted files need 205 * not waste disk bandwidth being created and removed. To realize this, 206 * we append vnodes to a "workitem" queue. When running with a soft 207 * updates implementation, most pending metadata dependencies should 208 * not wait for more than a few seconds. Thus, mounted on block devices 209 * are delayed only about a half the time that file data is delayed. 210 * Similarly, directory updates are more critical, so are only delayed 211 * about a third the time that file data is delayed. Thus, there are 212 * SYNCER_MAXDELAY queues that are processed round-robin at a rate of 213 * one each second (driven off the filesystem syncer process). The 214 * syncer_delayno variable indicates the next queue that is to be processed. 215 * Items that need to be processed soon are placed in this queue: 216 * 217 * syncer_workitem_pending[syncer_delayno] 218 * 219 * A delay of fifteen seconds is done by placing the request fifteen 220 * entries later in the queue: 221 * 222 * syncer_workitem_pending[(syncer_delayno + 15) & syncer_mask] 223 * 224 */ 225 static int syncer_delayno; 226 static long syncer_mask; 227 LIST_HEAD(synclist, bufobj); 228 static struct synclist *syncer_workitem_pending[2]; 229 /* 230 * The sync_mtx protects: 231 * bo->bo_synclist 232 * sync_vnode_count 233 * syncer_delayno 234 * syncer_state 235 * syncer_workitem_pending 236 * syncer_worklist_len 237 * rushjob 238 */ 239 static struct mtx sync_mtx; 240 static struct cv sync_wakeup; 241 242 #define SYNCER_MAXDELAY 32 243 static int syncer_maxdelay = SYNCER_MAXDELAY; /* maximum delay time */ 244 static int syncdelay = 30; /* max time to delay syncing data */ 245 static int filedelay = 30; /* time to delay syncing files */ 246 SYSCTL_INT(_kern, OID_AUTO, filedelay, CTLFLAG_RW, &filedelay, 0, ""); 247 static int dirdelay = 29; /* time to delay syncing directories */ 248 SYSCTL_INT(_kern, OID_AUTO, dirdelay, CTLFLAG_RW, &dirdelay, 0, ""); 249 static int metadelay = 28; /* time to delay syncing metadata */ 250 SYSCTL_INT(_kern, OID_AUTO, metadelay, CTLFLAG_RW, &metadelay, 0, ""); 251 static int rushjob; /* number of slots to run ASAP */ 252 static int stat_rush_requests; /* number of times I/O speeded up */ 253 SYSCTL_INT(_debug, OID_AUTO, rush_requests, CTLFLAG_RW, &stat_rush_requests, 0, ""); 254 255 /* 256 * When shutting down the syncer, run it at four times normal speed. 257 */ 258 #define SYNCER_SHUTDOWN_SPEEDUP 4 259 static int sync_vnode_count; 260 static int syncer_worklist_len; 261 static enum { SYNCER_RUNNING, SYNCER_SHUTTING_DOWN, SYNCER_FINAL_DELAY } 262 syncer_state; 263 264 /* 265 * Number of vnodes we want to exist at any one time. This is mostly used 266 * to size hash tables in vnode-related code. It is normally not used in 267 * getnewvnode(), as wantfreevnodes is normally nonzero.) 268 * 269 * XXX desiredvnodes is historical cruft and should not exist. 270 */ 271 int desiredvnodes; 272 SYSCTL_INT(_kern, KERN_MAXVNODES, maxvnodes, CTLFLAG_RW, 273 &desiredvnodes, 0, "Maximum number of vnodes"); 274 SYSCTL_INT(_kern, OID_AUTO, minvnodes, CTLFLAG_RW, 275 &wantfreevnodes, 0, "Minimum number of vnodes (legacy)"); 276 static int vnlru_nowhere; 277 SYSCTL_INT(_debug, OID_AUTO, vnlru_nowhere, CTLFLAG_RW, 278 &vnlru_nowhere, 0, "Number of times the vnlru process ran without success"); 279 280 /* 281 * Macros to control when a vnode is freed and recycled. All require 282 * the vnode interlock. 283 */ 284 #define VCANRECYCLE(vp) (((vp)->v_iflag & VI_FREE) && !(vp)->v_holdcnt) 285 #define VSHOULDFREE(vp) (!((vp)->v_iflag & VI_FREE) && !(vp)->v_holdcnt) 286 #define VSHOULDBUSY(vp) (((vp)->v_iflag & VI_FREE) && (vp)->v_holdcnt) 287 288 289 /* 290 * Initialize the vnode management data structures. 291 */ 292 #ifndef MAXVNODES_MAX 293 #define MAXVNODES_MAX 100000 294 #endif 295 static void 296 vntblinit(void *dummy __unused) 297 { 298 299 /* 300 * Desiredvnodes is a function of the physical memory size and 301 * the kernel's heap size. Specifically, desiredvnodes scales 302 * in proportion to the physical memory size until two fifths 303 * of the kernel's heap size is consumed by vnodes and vm 304 * objects. 305 */ 306 desiredvnodes = min(maxproc + cnt.v_page_count / 4, 2 * vm_kmem_size / 307 (5 * (sizeof(struct vm_object) + sizeof(struct vnode)))); 308 if (desiredvnodes > MAXVNODES_MAX) { 309 if (bootverbose) 310 printf("Reducing kern.maxvnodes %d -> %d\n", 311 desiredvnodes, MAXVNODES_MAX); 312 desiredvnodes = MAXVNODES_MAX; 313 } 314 wantfreevnodes = desiredvnodes / 4; 315 mtx_init(&mntid_mtx, "mntid", NULL, MTX_DEF); 316 TAILQ_INIT(&vnode_free_list); 317 mtx_init(&vnode_free_list_mtx, "vnode_free_list", NULL, MTX_DEF); 318 vnode_zone = uma_zcreate("VNODE", sizeof (struct vnode), NULL, NULL, 319 NULL, NULL, UMA_ALIGN_PTR, 0); 320 vnodepoll_zone = uma_zcreate("VNODEPOLL", sizeof (struct vpollinfo), 321 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); 322 /* 323 * Initialize the filesystem syncer. 324 */ 325 syncer_workitem_pending[WI_MPSAFEQ] = hashinit(syncer_maxdelay, M_VNODE, 326 &syncer_mask); 327 syncer_workitem_pending[WI_GIANTQ] = hashinit(syncer_maxdelay, M_VNODE, 328 &syncer_mask); 329 syncer_maxdelay = syncer_mask + 1; 330 mtx_init(&sync_mtx, "Syncer mtx", NULL, MTX_DEF); 331 cv_init(&sync_wakeup, "syncer"); 332 } 333 SYSINIT(vfs, SI_SUB_VFS, SI_ORDER_FIRST, vntblinit, NULL); 334 335 336 /* 337 * Mark a mount point as busy. Used to synchronize access and to delay 338 * unmounting. Interlock is not released on failure. 339 */ 340 int 341 vfs_busy(struct mount *mp, int flags, struct mtx *interlkp, 342 struct thread *td) 343 { 344 int lkflags; 345 346 MNT_ILOCK(mp); 347 MNT_REF(mp); 348 if (mp->mnt_kern_flag & MNTK_UNMOUNT) { 349 if (flags & LK_NOWAIT) { 350 MNT_REL(mp); 351 MNT_IUNLOCK(mp); 352 return (ENOENT); 353 } 354 if (interlkp) 355 mtx_unlock(interlkp); 356 mp->mnt_kern_flag |= MNTK_MWAIT; 357 /* 358 * Since all busy locks are shared except the exclusive 359 * lock granted when unmounting, the only place that a 360 * wakeup needs to be done is at the release of the 361 * exclusive lock at the end of dounmount. 362 */ 363 msleep(mp, MNT_MTX(mp), PVFS, "vfs_busy", 0); 364 MNT_REL(mp); 365 MNT_IUNLOCK(mp); 366 if (interlkp) 367 mtx_lock(interlkp); 368 return (ENOENT); 369 } 370 if (interlkp) 371 mtx_unlock(interlkp); 372 lkflags = LK_SHARED | LK_INTERLOCK; 373 if (lockmgr(&mp->mnt_lock, lkflags, MNT_MTX(mp))) 374 panic("vfs_busy: unexpected lock failure"); 375 return (0); 376 } 377 378 /* 379 * Free a busy filesystem. 380 */ 381 void 382 vfs_unbusy(struct mount *mp, struct thread *td) 383 { 384 385 lockmgr(&mp->mnt_lock, LK_RELEASE, NULL); 386 vfs_rel(mp); 387 } 388 389 /* 390 * Lookup a mount point by filesystem identifier. 391 */ 392 struct mount * 393 vfs_getvfs(fsid_t *fsid) 394 { 395 struct mount *mp; 396 397 mtx_lock(&mountlist_mtx); 398 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 399 if (mp->mnt_stat.f_fsid.val[0] == fsid->val[0] && 400 mp->mnt_stat.f_fsid.val[1] == fsid->val[1]) { 401 vfs_ref(mp); 402 mtx_unlock(&mountlist_mtx); 403 return (mp); 404 } 405 } 406 mtx_unlock(&mountlist_mtx); 407 return ((struct mount *) 0); 408 } 409 410 /* 411 * Check if a user can access privileged mount options. 412 */ 413 int 414 vfs_suser(struct mount *mp, struct thread *td) 415 { 416 int error; 417 418 /* 419 * If the thread is jailed, but this is not a jail-friendly file 420 * system, deny immediately. 421 */ 422 if (jailed(td->td_ucred) && !(mp->mnt_vfc->vfc_flags & VFCF_JAIL)) 423 return (EPERM); 424 425 /* 426 * If the file system was mounted outside a jail and a jailed thread 427 * tries to access it, deny immediately. 428 */ 429 if (!jailed(mp->mnt_cred) && jailed(td->td_ucred)) 430 return (EPERM); 431 432 /* 433 * If the file system was mounted inside different jail that the jail of 434 * the calling thread, deny immediately. 435 */ 436 if (jailed(mp->mnt_cred) && jailed(td->td_ucred) && 437 mp->mnt_cred->cr_prison != td->td_ucred->cr_prison) { 438 return (EPERM); 439 } 440 441 if ((mp->mnt_flag & MNT_USER) == 0 || 442 mp->mnt_cred->cr_uid != td->td_ucred->cr_uid) { 443 if ((error = priv_check(td, PRIV_VFS_MOUNT_OWNER)) != 0) 444 return (error); 445 } 446 return (0); 447 } 448 449 /* 450 * Get a new unique fsid. Try to make its val[0] unique, since this value 451 * will be used to create fake device numbers for stat(). Also try (but 452 * not so hard) make its val[0] unique mod 2^16, since some emulators only 453 * support 16-bit device numbers. We end up with unique val[0]'s for the 454 * first 2^16 calls and unique val[0]'s mod 2^16 for the first 2^8 calls. 455 * 456 * Keep in mind that several mounts may be running in parallel. Starting 457 * the search one past where the previous search terminated is both a 458 * micro-optimization and a defense against returning the same fsid to 459 * different mounts. 460 */ 461 void 462 vfs_getnewfsid(struct mount *mp) 463 { 464 static u_int16_t mntid_base; 465 struct mount *nmp; 466 fsid_t tfsid; 467 int mtype; 468 469 mtx_lock(&mntid_mtx); 470 mtype = mp->mnt_vfc->vfc_typenum; 471 tfsid.val[1] = mtype; 472 mtype = (mtype & 0xFF) << 24; 473 for (;;) { 474 tfsid.val[0] = makedev(255, 475 mtype | ((mntid_base & 0xFF00) << 8) | (mntid_base & 0xFF)); 476 mntid_base++; 477 if ((nmp = vfs_getvfs(&tfsid)) == NULL) 478 break; 479 vfs_rel(nmp); 480 } 481 mp->mnt_stat.f_fsid.val[0] = tfsid.val[0]; 482 mp->mnt_stat.f_fsid.val[1] = tfsid.val[1]; 483 mtx_unlock(&mntid_mtx); 484 } 485 486 /* 487 * Knob to control the precision of file timestamps: 488 * 489 * 0 = seconds only; nanoseconds zeroed. 490 * 1 = seconds and nanoseconds, accurate within 1/HZ. 491 * 2 = seconds and nanoseconds, truncated to microseconds. 492 * >=3 = seconds and nanoseconds, maximum precision. 493 */ 494 enum { TSP_SEC, TSP_HZ, TSP_USEC, TSP_NSEC }; 495 496 static int timestamp_precision = TSP_SEC; 497 SYSCTL_INT(_vfs, OID_AUTO, timestamp_precision, CTLFLAG_RW, 498 ×tamp_precision, 0, ""); 499 500 /* 501 * Get a current timestamp. 502 */ 503 void 504 vfs_timestamp(struct timespec *tsp) 505 { 506 struct timeval tv; 507 508 switch (timestamp_precision) { 509 case TSP_SEC: 510 tsp->tv_sec = time_second; 511 tsp->tv_nsec = 0; 512 break; 513 case TSP_HZ: 514 getnanotime(tsp); 515 break; 516 case TSP_USEC: 517 microtime(&tv); 518 TIMEVAL_TO_TIMESPEC(&tv, tsp); 519 break; 520 case TSP_NSEC: 521 default: 522 nanotime(tsp); 523 break; 524 } 525 } 526 527 /* 528 * Set vnode attributes to VNOVAL 529 */ 530 void 531 vattr_null(struct vattr *vap) 532 { 533 534 vap->va_type = VNON; 535 vap->va_size = VNOVAL; 536 vap->va_bytes = VNOVAL; 537 vap->va_mode = VNOVAL; 538 vap->va_nlink = VNOVAL; 539 vap->va_uid = VNOVAL; 540 vap->va_gid = VNOVAL; 541 vap->va_fsid = VNOVAL; 542 vap->va_fileid = VNOVAL; 543 vap->va_blocksize = VNOVAL; 544 vap->va_rdev = VNOVAL; 545 vap->va_atime.tv_sec = VNOVAL; 546 vap->va_atime.tv_nsec = VNOVAL; 547 vap->va_mtime.tv_sec = VNOVAL; 548 vap->va_mtime.tv_nsec = VNOVAL; 549 vap->va_ctime.tv_sec = VNOVAL; 550 vap->va_ctime.tv_nsec = VNOVAL; 551 vap->va_birthtime.tv_sec = VNOVAL; 552 vap->va_birthtime.tv_nsec = VNOVAL; 553 vap->va_flags = VNOVAL; 554 vap->va_gen = VNOVAL; 555 vap->va_vaflags = 0; 556 } 557 558 /* 559 * This routine is called when we have too many vnodes. It attempts 560 * to free <count> vnodes and will potentially free vnodes that still 561 * have VM backing store (VM backing store is typically the cause 562 * of a vnode blowout so we want to do this). Therefore, this operation 563 * is not considered cheap. 564 * 565 * A number of conditions may prevent a vnode from being reclaimed. 566 * the buffer cache may have references on the vnode, a directory 567 * vnode may still have references due to the namei cache representing 568 * underlying files, or the vnode may be in active use. It is not 569 * desireable to reuse such vnodes. These conditions may cause the 570 * number of vnodes to reach some minimum value regardless of what 571 * you set kern.maxvnodes to. Do not set kern.maxvnodes too low. 572 */ 573 static int 574 vlrureclaim(struct mount *mp) 575 { 576 struct thread *td; 577 struct vnode *vp; 578 int done; 579 int trigger; 580 int usevnodes; 581 int count; 582 583 /* 584 * Calculate the trigger point, don't allow user 585 * screwups to blow us up. This prevents us from 586 * recycling vnodes with lots of resident pages. We 587 * aren't trying to free memory, we are trying to 588 * free vnodes. 589 */ 590 usevnodes = desiredvnodes; 591 if (usevnodes <= 0) 592 usevnodes = 1; 593 trigger = cnt.v_page_count * 2 / usevnodes; 594 done = 0; 595 td = curthread; 596 vn_start_write(NULL, &mp, V_WAIT); 597 MNT_ILOCK(mp); 598 count = mp->mnt_nvnodelistsize / 10 + 1; 599 while (count != 0) { 600 vp = TAILQ_FIRST(&mp->mnt_nvnodelist); 601 while (vp != NULL && vp->v_type == VMARKER) 602 vp = TAILQ_NEXT(vp, v_nmntvnodes); 603 if (vp == NULL) 604 break; 605 TAILQ_REMOVE(&mp->mnt_nvnodelist, vp, v_nmntvnodes); 606 TAILQ_INSERT_TAIL(&mp->mnt_nvnodelist, vp, v_nmntvnodes); 607 --count; 608 if (!VI_TRYLOCK(vp)) 609 goto next_iter; 610 /* 611 * If it's been deconstructed already, it's still 612 * referenced, or it exceeds the trigger, skip it. 613 */ 614 if (vp->v_usecount || !LIST_EMPTY(&(vp)->v_cache_src) || 615 (vp->v_iflag & VI_DOOMED) != 0 || (vp->v_object != NULL && 616 vp->v_object->resident_page_count > trigger)) { 617 VI_UNLOCK(vp); 618 goto next_iter; 619 } 620 MNT_IUNLOCK(mp); 621 vholdl(vp); 622 if (VOP_LOCK(vp, LK_INTERLOCK|LK_EXCLUSIVE|LK_NOWAIT)) { 623 vdrop(vp); 624 goto next_iter_mntunlocked; 625 } 626 VI_LOCK(vp); 627 /* 628 * v_usecount may have been bumped after VOP_LOCK() dropped 629 * the vnode interlock and before it was locked again. 630 * 631 * It is not necessary to recheck VI_DOOMED because it can 632 * only be set by another thread that holds both the vnode 633 * lock and vnode interlock. If another thread has the 634 * vnode lock before we get to VOP_LOCK() and obtains the 635 * vnode interlock after VOP_LOCK() drops the vnode 636 * interlock, the other thread will be unable to drop the 637 * vnode lock before our VOP_LOCK() call fails. 638 */ 639 if (vp->v_usecount || !LIST_EMPTY(&(vp)->v_cache_src) || 640 (vp->v_object != NULL && 641 vp->v_object->resident_page_count > trigger)) { 642 VOP_UNLOCK(vp, LK_INTERLOCK); 643 goto next_iter_mntunlocked; 644 } 645 KASSERT((vp->v_iflag & VI_DOOMED) == 0, 646 ("VI_DOOMED unexpectedly detected in vlrureclaim()")); 647 vgonel(vp); 648 VOP_UNLOCK(vp, 0); 649 vdropl(vp); 650 done++; 651 next_iter_mntunlocked: 652 if ((count % 256) != 0) 653 goto relock_mnt; 654 goto yield; 655 next_iter: 656 if ((count % 256) != 0) 657 continue; 658 MNT_IUNLOCK(mp); 659 yield: 660 uio_yield(); 661 relock_mnt: 662 MNT_ILOCK(mp); 663 } 664 MNT_IUNLOCK(mp); 665 vn_finished_write(mp); 666 return done; 667 } 668 669 /* 670 * Attempt to keep the free list at wantfreevnodes length. 671 */ 672 static void 673 vnlru_free(int count) 674 { 675 struct vnode *vp; 676 int vfslocked; 677 678 mtx_assert(&vnode_free_list_mtx, MA_OWNED); 679 for (; count > 0; count--) { 680 vp = TAILQ_FIRST(&vnode_free_list); 681 /* 682 * The list can be modified while the free_list_mtx 683 * has been dropped and vp could be NULL here. 684 */ 685 if (!vp) 686 break; 687 VNASSERT(vp->v_op != NULL, vp, 688 ("vnlru_free: vnode already reclaimed.")); 689 TAILQ_REMOVE(&vnode_free_list, vp, v_freelist); 690 /* 691 * Don't recycle if we can't get the interlock. 692 */ 693 if (!VI_TRYLOCK(vp)) { 694 TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_freelist); 695 continue; 696 } 697 VNASSERT(VCANRECYCLE(vp), vp, 698 ("vp inconsistent on freelist")); 699 freevnodes--; 700 vp->v_iflag &= ~VI_FREE; 701 vholdl(vp); 702 mtx_unlock(&vnode_free_list_mtx); 703 VI_UNLOCK(vp); 704 vfslocked = VFS_LOCK_GIANT(vp->v_mount); 705 vtryrecycle(vp); 706 VFS_UNLOCK_GIANT(vfslocked); 707 /* 708 * If the recycled succeeded this vdrop will actually free 709 * the vnode. If not it will simply place it back on 710 * the free list. 711 */ 712 vdrop(vp); 713 mtx_lock(&vnode_free_list_mtx); 714 } 715 } 716 /* 717 * Attempt to recycle vnodes in a context that is always safe to block. 718 * Calling vlrurecycle() from the bowels of filesystem code has some 719 * interesting deadlock problems. 720 */ 721 static struct proc *vnlruproc; 722 static int vnlruproc_sig; 723 724 static void 725 vnlru_proc(void) 726 { 727 struct mount *mp, *nmp; 728 int done; 729 struct proc *p = vnlruproc; 730 struct thread *td = curthread; 731 732 EVENTHANDLER_REGISTER(shutdown_pre_sync, kproc_shutdown, p, 733 SHUTDOWN_PRI_FIRST); 734 735 mtx_lock(&Giant); 736 737 for (;;) { 738 kproc_suspend_check(p); 739 mtx_lock(&vnode_free_list_mtx); 740 if (freevnodes > wantfreevnodes) 741 vnlru_free(freevnodes - wantfreevnodes); 742 if (numvnodes <= desiredvnodes * 9 / 10) { 743 vnlruproc_sig = 0; 744 wakeup(&vnlruproc_sig); 745 msleep(vnlruproc, &vnode_free_list_mtx, 746 PVFS|PDROP, "vlruwt", hz); 747 continue; 748 } 749 mtx_unlock(&vnode_free_list_mtx); 750 done = 0; 751 mtx_lock(&mountlist_mtx); 752 for (mp = TAILQ_FIRST(&mountlist); mp != NULL; mp = nmp) { 753 int vfsunlocked; 754 if (vfs_busy(mp, LK_NOWAIT, &mountlist_mtx, td)) { 755 nmp = TAILQ_NEXT(mp, mnt_list); 756 continue; 757 } 758 if (!VFS_NEEDSGIANT(mp)) { 759 mtx_unlock(&Giant); 760 vfsunlocked = 1; 761 } else 762 vfsunlocked = 0; 763 done += vlrureclaim(mp); 764 if (vfsunlocked) 765 mtx_lock(&Giant); 766 mtx_lock(&mountlist_mtx); 767 nmp = TAILQ_NEXT(mp, mnt_list); 768 vfs_unbusy(mp, td); 769 } 770 mtx_unlock(&mountlist_mtx); 771 if (done == 0) { 772 EVENTHANDLER_INVOKE(vfs_lowvnodes, desiredvnodes / 10); 773 #if 0 774 /* These messages are temporary debugging aids */ 775 if (vnlru_nowhere < 5) 776 printf("vnlru process getting nowhere..\n"); 777 else if (vnlru_nowhere == 5) 778 printf("vnlru process messages stopped.\n"); 779 #endif 780 vnlru_nowhere++; 781 tsleep(vnlruproc, PPAUSE, "vlrup", hz * 3); 782 } else 783 uio_yield(); 784 } 785 } 786 787 static struct kproc_desc vnlru_kp = { 788 "vnlru", 789 vnlru_proc, 790 &vnlruproc 791 }; 792 SYSINIT(vnlru, SI_SUB_KTHREAD_UPDATE, SI_ORDER_FIRST, kproc_start, 793 &vnlru_kp); 794 795 /* 796 * Routines having to do with the management of the vnode table. 797 */ 798 799 static void 800 vdestroy(struct vnode *vp) 801 { 802 struct bufobj *bo; 803 804 CTR1(KTR_VFS, "vdestroy vp %p", vp); 805 mtx_lock(&vnode_free_list_mtx); 806 numvnodes--; 807 mtx_unlock(&vnode_free_list_mtx); 808 bo = &vp->v_bufobj; 809 VNASSERT((vp->v_iflag & VI_FREE) == 0, vp, 810 ("cleaned vnode still on the free list.")); 811 VNASSERT(vp->v_data == NULL, vp, ("cleaned vnode isn't")); 812 VNASSERT(vp->v_holdcnt == 0, vp, ("Non-zero hold count")); 813 VNASSERT(vp->v_usecount == 0, vp, ("Non-zero use count")); 814 VNASSERT(vp->v_writecount == 0, vp, ("Non-zero write count")); 815 VNASSERT(bo->bo_numoutput == 0, vp, ("Clean vnode has pending I/O's")); 816 VNASSERT(bo->bo_clean.bv_cnt == 0, vp, ("cleanbufcnt not 0")); 817 VNASSERT(bo->bo_clean.bv_root == NULL, vp, ("cleanblkroot not NULL")); 818 VNASSERT(bo->bo_dirty.bv_cnt == 0, vp, ("dirtybufcnt not 0")); 819 VNASSERT(bo->bo_dirty.bv_root == NULL, vp, ("dirtyblkroot not NULL")); 820 VNASSERT(TAILQ_EMPTY(&vp->v_cache_dst), vp, ("vp has namecache dst")); 821 VNASSERT(LIST_EMPTY(&vp->v_cache_src), vp, ("vp has namecache src")); 822 VI_UNLOCK(vp); 823 #ifdef MAC 824 mac_vnode_destroy(vp); 825 #endif 826 if (vp->v_pollinfo != NULL) { 827 knlist_destroy(&vp->v_pollinfo->vpi_selinfo.si_note); 828 mtx_destroy(&vp->v_pollinfo->vpi_lock); 829 uma_zfree(vnodepoll_zone, vp->v_pollinfo); 830 } 831 #ifdef INVARIANTS 832 /* XXX Elsewhere we can detect an already freed vnode via NULL v_op. */ 833 vp->v_op = NULL; 834 #endif 835 lockdestroy(vp->v_vnlock); 836 mtx_destroy(&vp->v_interlock); 837 mtx_destroy(BO_MTX(bo)); 838 uma_zfree(vnode_zone, vp); 839 } 840 841 /* 842 * Try to recycle a freed vnode. We abort if anyone picks up a reference 843 * before we actually vgone(). This function must be called with the vnode 844 * held to prevent the vnode from being returned to the free list midway 845 * through vgone(). 846 */ 847 static int 848 vtryrecycle(struct vnode *vp) 849 { 850 struct mount *vnmp; 851 852 CTR1(KTR_VFS, "vtryrecycle: trying vp %p", vp); 853 VNASSERT(vp->v_holdcnt, vp, 854 ("vtryrecycle: Recycling vp %p without a reference.", vp)); 855 /* 856 * This vnode may found and locked via some other list, if so we 857 * can't recycle it yet. 858 */ 859 if (VOP_LOCK(vp, LK_EXCLUSIVE | LK_NOWAIT) != 0) 860 return (EWOULDBLOCK); 861 /* 862 * Don't recycle if its filesystem is being suspended. 863 */ 864 if (vn_start_write(vp, &vnmp, V_NOWAIT) != 0) { 865 VOP_UNLOCK(vp, 0); 866 return (EBUSY); 867 } 868 /* 869 * If we got this far, we need to acquire the interlock and see if 870 * anyone picked up this vnode from another list. If not, we will 871 * mark it with DOOMED via vgonel() so that anyone who does find it 872 * will skip over it. 873 */ 874 VI_LOCK(vp); 875 if (vp->v_usecount) { 876 VOP_UNLOCK(vp, LK_INTERLOCK); 877 vn_finished_write(vnmp); 878 return (EBUSY); 879 } 880 if ((vp->v_iflag & VI_DOOMED) == 0) 881 vgonel(vp); 882 VOP_UNLOCK(vp, LK_INTERLOCK); 883 vn_finished_write(vnmp); 884 CTR1(KTR_VFS, "vtryrecycle: recycled vp %p", vp); 885 return (0); 886 } 887 888 /* 889 * Return the next vnode from the free list. 890 */ 891 int 892 getnewvnode(const char *tag, struct mount *mp, struct vop_vector *vops, 893 struct vnode **vpp) 894 { 895 struct vnode *vp = NULL; 896 struct bufobj *bo; 897 898 mtx_lock(&vnode_free_list_mtx); 899 /* 900 * Lend our context to reclaim vnodes if they've exceeded the max. 901 */ 902 if (freevnodes > wantfreevnodes) 903 vnlru_free(1); 904 /* 905 * Wait for available vnodes. 906 */ 907 if (numvnodes > desiredvnodes) { 908 if (mp != NULL && (mp->mnt_kern_flag & MNTK_SUSPEND)) { 909 /* 910 * File system is beeing suspended, we cannot risk a 911 * deadlock here, so allocate new vnode anyway. 912 */ 913 if (freevnodes > wantfreevnodes) 914 vnlru_free(freevnodes - wantfreevnodes); 915 goto alloc; 916 } 917 if (vnlruproc_sig == 0) { 918 vnlruproc_sig = 1; /* avoid unnecessary wakeups */ 919 wakeup(vnlruproc); 920 } 921 msleep(&vnlruproc_sig, &vnode_free_list_mtx, PVFS, 922 "vlruwk", hz); 923 #if 0 /* XXX Not all VFS_VGET/ffs_vget callers check returns. */ 924 if (numvnodes > desiredvnodes) { 925 mtx_unlock(&vnode_free_list_mtx); 926 return (ENFILE); 927 } 928 #endif 929 } 930 alloc: 931 numvnodes++; 932 mtx_unlock(&vnode_free_list_mtx); 933 vp = (struct vnode *) uma_zalloc(vnode_zone, M_WAITOK|M_ZERO); 934 /* 935 * Setup locks. 936 */ 937 vp->v_vnlock = &vp->v_lock; 938 mtx_init(&vp->v_interlock, "vnode interlock", NULL, MTX_DEF); 939 /* 940 * By default, don't allow shared locks unless filesystems 941 * opt-in. 942 */ 943 lockinit(vp->v_vnlock, PVFS, tag, VLKTIMEOUT, LK_NOSHARE); 944 /* 945 * Initialize bufobj. 946 */ 947 bo = &vp->v_bufobj; 948 bo->__bo_vnode = vp; 949 mtx_init(BO_MTX(bo), "bufobj interlock", NULL, MTX_DEF); 950 bo->bo_ops = &buf_ops_bio; 951 bo->bo_private = vp; 952 TAILQ_INIT(&bo->bo_clean.bv_hd); 953 TAILQ_INIT(&bo->bo_dirty.bv_hd); 954 /* 955 * Initialize namecache. 956 */ 957 LIST_INIT(&vp->v_cache_src); 958 TAILQ_INIT(&vp->v_cache_dst); 959 /* 960 * Finalize various vnode identity bits. 961 */ 962 vp->v_type = VNON; 963 vp->v_tag = tag; 964 vp->v_op = vops; 965 v_incr_usecount(vp); 966 vp->v_data = 0; 967 #ifdef MAC 968 mac_vnode_init(vp); 969 if (mp != NULL && (mp->mnt_flag & MNT_MULTILABEL) == 0) 970 mac_vnode_associate_singlelabel(mp, vp); 971 else if (mp == NULL) 972 printf("NULL mp in getnewvnode()\n"); 973 #endif 974 if (mp != NULL) { 975 bo->bo_bsize = mp->mnt_stat.f_iosize; 976 if ((mp->mnt_kern_flag & MNTK_NOKNOTE) != 0) 977 vp->v_vflag |= VV_NOKNOTE; 978 } 979 980 CTR2(KTR_VFS, "getnewvnode: mp %p vp %p", mp, vp); 981 *vpp = vp; 982 return (0); 983 } 984 985 /* 986 * Delete from old mount point vnode list, if on one. 987 */ 988 static void 989 delmntque(struct vnode *vp) 990 { 991 struct mount *mp; 992 993 mp = vp->v_mount; 994 if (mp == NULL) 995 return; 996 MNT_ILOCK(mp); 997 vp->v_mount = NULL; 998 VNASSERT(mp->mnt_nvnodelistsize > 0, vp, 999 ("bad mount point vnode list size")); 1000 TAILQ_REMOVE(&mp->mnt_nvnodelist, vp, v_nmntvnodes); 1001 mp->mnt_nvnodelistsize--; 1002 MNT_REL(mp); 1003 MNT_IUNLOCK(mp); 1004 } 1005 1006 static void 1007 insmntque_stddtr(struct vnode *vp, void *dtr_arg) 1008 { 1009 1010 vp->v_data = NULL; 1011 vp->v_op = &dead_vnodeops; 1012 /* XXX non mp-safe fs may still call insmntque with vnode 1013 unlocked */ 1014 if (!VOP_ISLOCKED(vp)) 1015 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 1016 vgone(vp); 1017 vput(vp); 1018 } 1019 1020 /* 1021 * Insert into list of vnodes for the new mount point, if available. 1022 */ 1023 int 1024 insmntque1(struct vnode *vp, struct mount *mp, 1025 void (*dtr)(struct vnode *, void *), void *dtr_arg) 1026 { 1027 1028 KASSERT(vp->v_mount == NULL, 1029 ("insmntque: vnode already on per mount vnode list")); 1030 VNASSERT(mp != NULL, vp, ("Don't call insmntque(foo, NULL)")); 1031 MNT_ILOCK(mp); 1032 if ((mp->mnt_kern_flag & MNTK_NOINSMNTQ) != 0 && 1033 mp->mnt_nvnodelistsize == 0) { 1034 MNT_IUNLOCK(mp); 1035 if (dtr != NULL) 1036 dtr(vp, dtr_arg); 1037 return (EBUSY); 1038 } 1039 vp->v_mount = mp; 1040 MNT_REF(mp); 1041 TAILQ_INSERT_TAIL(&mp->mnt_nvnodelist, vp, v_nmntvnodes); 1042 VNASSERT(mp->mnt_nvnodelistsize >= 0, vp, 1043 ("neg mount point vnode list size")); 1044 mp->mnt_nvnodelistsize++; 1045 MNT_IUNLOCK(mp); 1046 return (0); 1047 } 1048 1049 int 1050 insmntque(struct vnode *vp, struct mount *mp) 1051 { 1052 1053 return (insmntque1(vp, mp, insmntque_stddtr, NULL)); 1054 } 1055 1056 /* 1057 * Flush out and invalidate all buffers associated with a bufobj 1058 * Called with the underlying object locked. 1059 */ 1060 int 1061 bufobj_invalbuf(struct bufobj *bo, int flags, struct thread *td, int slpflag, 1062 int slptimeo) 1063 { 1064 int error; 1065 1066 BO_LOCK(bo); 1067 if (flags & V_SAVE) { 1068 error = bufobj_wwait(bo, slpflag, slptimeo); 1069 if (error) { 1070 BO_UNLOCK(bo); 1071 return (error); 1072 } 1073 if (bo->bo_dirty.bv_cnt > 0) { 1074 BO_UNLOCK(bo); 1075 if ((error = BO_SYNC(bo, MNT_WAIT, td)) != 0) 1076 return (error); 1077 /* 1078 * XXX We could save a lock/unlock if this was only 1079 * enabled under INVARIANTS 1080 */ 1081 BO_LOCK(bo); 1082 if (bo->bo_numoutput > 0 || bo->bo_dirty.bv_cnt > 0) 1083 panic("vinvalbuf: dirty bufs"); 1084 } 1085 } 1086 /* 1087 * If you alter this loop please notice that interlock is dropped and 1088 * reacquired in flushbuflist. Special care is needed to ensure that 1089 * no race conditions occur from this. 1090 */ 1091 do { 1092 error = flushbuflist(&bo->bo_clean, 1093 flags, bo, slpflag, slptimeo); 1094 if (error == 0) 1095 error = flushbuflist(&bo->bo_dirty, 1096 flags, bo, slpflag, slptimeo); 1097 if (error != 0 && error != EAGAIN) { 1098 BO_UNLOCK(bo); 1099 return (error); 1100 } 1101 } while (error != 0); 1102 1103 /* 1104 * Wait for I/O to complete. XXX needs cleaning up. The vnode can 1105 * have write I/O in-progress but if there is a VM object then the 1106 * VM object can also have read-I/O in-progress. 1107 */ 1108 do { 1109 bufobj_wwait(bo, 0, 0); 1110 BO_UNLOCK(bo); 1111 if (bo->bo_object != NULL) { 1112 VM_OBJECT_LOCK(bo->bo_object); 1113 vm_object_pip_wait(bo->bo_object, "bovlbx"); 1114 VM_OBJECT_UNLOCK(bo->bo_object); 1115 } 1116 BO_LOCK(bo); 1117 } while (bo->bo_numoutput > 0); 1118 BO_UNLOCK(bo); 1119 1120 /* 1121 * Destroy the copy in the VM cache, too. 1122 */ 1123 if (bo->bo_object != NULL) { 1124 VM_OBJECT_LOCK(bo->bo_object); 1125 vm_object_page_remove(bo->bo_object, 0, 0, 1126 (flags & V_SAVE) ? TRUE : FALSE); 1127 VM_OBJECT_UNLOCK(bo->bo_object); 1128 } 1129 1130 #ifdef INVARIANTS 1131 BO_LOCK(bo); 1132 if ((flags & (V_ALT | V_NORMAL)) == 0 && 1133 (bo->bo_dirty.bv_cnt > 0 || bo->bo_clean.bv_cnt > 0)) 1134 panic("vinvalbuf: flush failed"); 1135 BO_UNLOCK(bo); 1136 #endif 1137 return (0); 1138 } 1139 1140 /* 1141 * Flush out and invalidate all buffers associated with a vnode. 1142 * Called with the underlying object locked. 1143 */ 1144 int 1145 vinvalbuf(struct vnode *vp, int flags, struct thread *td, int slpflag, 1146 int slptimeo) 1147 { 1148 1149 CTR2(KTR_VFS, "vinvalbuf vp %p flags %d", vp, flags); 1150 ASSERT_VOP_LOCKED(vp, "vinvalbuf"); 1151 return (bufobj_invalbuf(&vp->v_bufobj, flags, td, slpflag, slptimeo)); 1152 } 1153 1154 /* 1155 * Flush out buffers on the specified list. 1156 * 1157 */ 1158 static int 1159 flushbuflist( struct bufv *bufv, int flags, struct bufobj *bo, int slpflag, 1160 int slptimeo) 1161 { 1162 struct buf *bp, *nbp; 1163 int retval, error; 1164 daddr_t lblkno; 1165 b_xflags_t xflags; 1166 1167 ASSERT_BO_LOCKED(bo); 1168 1169 retval = 0; 1170 TAILQ_FOREACH_SAFE(bp, &bufv->bv_hd, b_bobufs, nbp) { 1171 if (((flags & V_NORMAL) && (bp->b_xflags & BX_ALTDATA)) || 1172 ((flags & V_ALT) && (bp->b_xflags & BX_ALTDATA) == 0)) { 1173 continue; 1174 } 1175 lblkno = 0; 1176 xflags = 0; 1177 if (nbp != NULL) { 1178 lblkno = nbp->b_lblkno; 1179 xflags = nbp->b_xflags & 1180 (BX_BKGRDMARKER | BX_VNDIRTY | BX_VNCLEAN); 1181 } 1182 retval = EAGAIN; 1183 error = BUF_TIMELOCK(bp, 1184 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, BO_MTX(bo), 1185 "flushbuf", slpflag, slptimeo); 1186 if (error) { 1187 BO_LOCK(bo); 1188 return (error != ENOLCK ? error : EAGAIN); 1189 } 1190 KASSERT(bp->b_bufobj == bo, 1191 ("bp %p wrong b_bufobj %p should be %p", 1192 bp, bp->b_bufobj, bo)); 1193 if (bp->b_bufobj != bo) { /* XXX: necessary ? */ 1194 BUF_UNLOCK(bp); 1195 BO_LOCK(bo); 1196 return (EAGAIN); 1197 } 1198 /* 1199 * XXX Since there are no node locks for NFS, I 1200 * believe there is a slight chance that a delayed 1201 * write will occur while sleeping just above, so 1202 * check for it. 1203 */ 1204 if (((bp->b_flags & (B_DELWRI | B_INVAL)) == B_DELWRI) && 1205 (flags & V_SAVE)) { 1206 bremfree(bp); 1207 bp->b_flags |= B_ASYNC; 1208 bwrite(bp); 1209 BO_LOCK(bo); 1210 return (EAGAIN); /* XXX: why not loop ? */ 1211 } 1212 bremfree(bp); 1213 bp->b_flags |= (B_INVAL | B_RELBUF); 1214 bp->b_flags &= ~B_ASYNC; 1215 brelse(bp); 1216 BO_LOCK(bo); 1217 if (nbp != NULL && 1218 (nbp->b_bufobj != bo || 1219 nbp->b_lblkno != lblkno || 1220 (nbp->b_xflags & 1221 (BX_BKGRDMARKER | BX_VNDIRTY | BX_VNCLEAN)) != xflags)) 1222 break; /* nbp invalid */ 1223 } 1224 return (retval); 1225 } 1226 1227 /* 1228 * Truncate a file's buffer and pages to a specified length. This 1229 * is in lieu of the old vinvalbuf mechanism, which performed unneeded 1230 * sync activity. 1231 */ 1232 int 1233 vtruncbuf(struct vnode *vp, struct ucred *cred, struct thread *td, 1234 off_t length, int blksize) 1235 { 1236 struct buf *bp, *nbp; 1237 int anyfreed; 1238 int trunclbn; 1239 struct bufobj *bo; 1240 1241 CTR2(KTR_VFS, "vtruncbuf vp %p length %jd", vp, length); 1242 /* 1243 * Round up to the *next* lbn. 1244 */ 1245 trunclbn = (length + blksize - 1) / blksize; 1246 1247 ASSERT_VOP_LOCKED(vp, "vtruncbuf"); 1248 restart: 1249 bo = &vp->v_bufobj; 1250 BO_LOCK(bo); 1251 anyfreed = 1; 1252 for (;anyfreed;) { 1253 anyfreed = 0; 1254 TAILQ_FOREACH_SAFE(bp, &bo->bo_clean.bv_hd, b_bobufs, nbp) { 1255 if (bp->b_lblkno < trunclbn) 1256 continue; 1257 if (BUF_LOCK(bp, 1258 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, 1259 BO_MTX(bo)) == ENOLCK) 1260 goto restart; 1261 1262 bremfree(bp); 1263 bp->b_flags |= (B_INVAL | B_RELBUF); 1264 bp->b_flags &= ~B_ASYNC; 1265 brelse(bp); 1266 anyfreed = 1; 1267 1268 if (nbp != NULL && 1269 (((nbp->b_xflags & BX_VNCLEAN) == 0) || 1270 (nbp->b_vp != vp) || 1271 (nbp->b_flags & B_DELWRI))) { 1272 goto restart; 1273 } 1274 BO_LOCK(bo); 1275 } 1276 1277 TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) { 1278 if (bp->b_lblkno < trunclbn) 1279 continue; 1280 if (BUF_LOCK(bp, 1281 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, 1282 BO_MTX(bo)) == ENOLCK) 1283 goto restart; 1284 bremfree(bp); 1285 bp->b_flags |= (B_INVAL | B_RELBUF); 1286 bp->b_flags &= ~B_ASYNC; 1287 brelse(bp); 1288 anyfreed = 1; 1289 if (nbp != NULL && 1290 (((nbp->b_xflags & BX_VNDIRTY) == 0) || 1291 (nbp->b_vp != vp) || 1292 (nbp->b_flags & B_DELWRI) == 0)) { 1293 goto restart; 1294 } 1295 BO_LOCK(bo); 1296 } 1297 } 1298 1299 if (length > 0) { 1300 restartsync: 1301 TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) { 1302 if (bp->b_lblkno > 0) 1303 continue; 1304 /* 1305 * Since we hold the vnode lock this should only 1306 * fail if we're racing with the buf daemon. 1307 */ 1308 if (BUF_LOCK(bp, 1309 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, 1310 BO_MTX(bo)) == ENOLCK) { 1311 goto restart; 1312 } 1313 VNASSERT((bp->b_flags & B_DELWRI), vp, 1314 ("buf(%p) on dirty queue without DELWRI", bp)); 1315 1316 bremfree(bp); 1317 bawrite(bp); 1318 BO_LOCK(bo); 1319 goto restartsync; 1320 } 1321 } 1322 1323 bufobj_wwait(bo, 0, 0); 1324 BO_UNLOCK(bo); 1325 vnode_pager_setsize(vp, length); 1326 1327 return (0); 1328 } 1329 1330 /* 1331 * buf_splay() - splay tree core for the clean/dirty list of buffers in 1332 * a vnode. 1333 * 1334 * NOTE: We have to deal with the special case of a background bitmap 1335 * buffer, a situation where two buffers will have the same logical 1336 * block offset. We want (1) only the foreground buffer to be accessed 1337 * in a lookup and (2) must differentiate between the foreground and 1338 * background buffer in the splay tree algorithm because the splay 1339 * tree cannot normally handle multiple entities with the same 'index'. 1340 * We accomplish this by adding differentiating flags to the splay tree's 1341 * numerical domain. 1342 */ 1343 static 1344 struct buf * 1345 buf_splay(daddr_t lblkno, b_xflags_t xflags, struct buf *root) 1346 { 1347 struct buf dummy; 1348 struct buf *lefttreemax, *righttreemin, *y; 1349 1350 if (root == NULL) 1351 return (NULL); 1352 lefttreemax = righttreemin = &dummy; 1353 for (;;) { 1354 if (lblkno < root->b_lblkno || 1355 (lblkno == root->b_lblkno && 1356 (xflags & BX_BKGRDMARKER) < (root->b_xflags & BX_BKGRDMARKER))) { 1357 if ((y = root->b_left) == NULL) 1358 break; 1359 if (lblkno < y->b_lblkno) { 1360 /* Rotate right. */ 1361 root->b_left = y->b_right; 1362 y->b_right = root; 1363 root = y; 1364 if ((y = root->b_left) == NULL) 1365 break; 1366 } 1367 /* Link into the new root's right tree. */ 1368 righttreemin->b_left = root; 1369 righttreemin = root; 1370 } else if (lblkno > root->b_lblkno || 1371 (lblkno == root->b_lblkno && 1372 (xflags & BX_BKGRDMARKER) > (root->b_xflags & BX_BKGRDMARKER))) { 1373 if ((y = root->b_right) == NULL) 1374 break; 1375 if (lblkno > y->b_lblkno) { 1376 /* Rotate left. */ 1377 root->b_right = y->b_left; 1378 y->b_left = root; 1379 root = y; 1380 if ((y = root->b_right) == NULL) 1381 break; 1382 } 1383 /* Link into the new root's left tree. */ 1384 lefttreemax->b_right = root; 1385 lefttreemax = root; 1386 } else { 1387 break; 1388 } 1389 root = y; 1390 } 1391 /* Assemble the new root. */ 1392 lefttreemax->b_right = root->b_left; 1393 righttreemin->b_left = root->b_right; 1394 root->b_left = dummy.b_right; 1395 root->b_right = dummy.b_left; 1396 return (root); 1397 } 1398 1399 static void 1400 buf_vlist_remove(struct buf *bp) 1401 { 1402 struct buf *root; 1403 struct bufv *bv; 1404 1405 KASSERT(bp->b_bufobj != NULL, ("No b_bufobj %p", bp)); 1406 ASSERT_BO_LOCKED(bp->b_bufobj); 1407 KASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) != 1408 (BX_VNDIRTY|BX_VNCLEAN), 1409 ("buf_vlist_remove: Buf %p is on two lists", bp)); 1410 if (bp->b_xflags & BX_VNDIRTY) 1411 bv = &bp->b_bufobj->bo_dirty; 1412 else 1413 bv = &bp->b_bufobj->bo_clean; 1414 if (bp != bv->bv_root) { 1415 root = buf_splay(bp->b_lblkno, bp->b_xflags, bv->bv_root); 1416 KASSERT(root == bp, ("splay lookup failed in remove")); 1417 } 1418 if (bp->b_left == NULL) { 1419 root = bp->b_right; 1420 } else { 1421 root = buf_splay(bp->b_lblkno, bp->b_xflags, bp->b_left); 1422 root->b_right = bp->b_right; 1423 } 1424 bv->bv_root = root; 1425 TAILQ_REMOVE(&bv->bv_hd, bp, b_bobufs); 1426 bv->bv_cnt--; 1427 bp->b_xflags &= ~(BX_VNDIRTY | BX_VNCLEAN); 1428 } 1429 1430 /* 1431 * Add the buffer to the sorted clean or dirty block list using a 1432 * splay tree algorithm. 1433 * 1434 * NOTE: xflags is passed as a constant, optimizing this inline function! 1435 */ 1436 static void 1437 buf_vlist_add(struct buf *bp, struct bufobj *bo, b_xflags_t xflags) 1438 { 1439 struct buf *root; 1440 struct bufv *bv; 1441 1442 ASSERT_BO_LOCKED(bo); 1443 KASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) == 0, 1444 ("buf_vlist_add: Buf %p has existing xflags %d", bp, bp->b_xflags)); 1445 bp->b_xflags |= xflags; 1446 if (xflags & BX_VNDIRTY) 1447 bv = &bo->bo_dirty; 1448 else 1449 bv = &bo->bo_clean; 1450 1451 root = buf_splay(bp->b_lblkno, bp->b_xflags, bv->bv_root); 1452 if (root == NULL) { 1453 bp->b_left = NULL; 1454 bp->b_right = NULL; 1455 TAILQ_INSERT_TAIL(&bv->bv_hd, bp, b_bobufs); 1456 } else if (bp->b_lblkno < root->b_lblkno || 1457 (bp->b_lblkno == root->b_lblkno && 1458 (bp->b_xflags & BX_BKGRDMARKER) < (root->b_xflags & BX_BKGRDMARKER))) { 1459 bp->b_left = root->b_left; 1460 bp->b_right = root; 1461 root->b_left = NULL; 1462 TAILQ_INSERT_BEFORE(root, bp, b_bobufs); 1463 } else { 1464 bp->b_right = root->b_right; 1465 bp->b_left = root; 1466 root->b_right = NULL; 1467 TAILQ_INSERT_AFTER(&bv->bv_hd, root, bp, b_bobufs); 1468 } 1469 bv->bv_cnt++; 1470 bv->bv_root = bp; 1471 } 1472 1473 /* 1474 * Lookup a buffer using the splay tree. Note that we specifically avoid 1475 * shadow buffers used in background bitmap writes. 1476 * 1477 * This code isn't quite efficient as it could be because we are maintaining 1478 * two sorted lists and do not know which list the block resides in. 1479 * 1480 * During a "make buildworld" the desired buffer is found at one of 1481 * the roots more than 60% of the time. Thus, checking both roots 1482 * before performing either splay eliminates unnecessary splays on the 1483 * first tree splayed. 1484 */ 1485 struct buf * 1486 gbincore(struct bufobj *bo, daddr_t lblkno) 1487 { 1488 struct buf *bp; 1489 1490 ASSERT_BO_LOCKED(bo); 1491 if ((bp = bo->bo_clean.bv_root) != NULL && 1492 bp->b_lblkno == lblkno && !(bp->b_xflags & BX_BKGRDMARKER)) 1493 return (bp); 1494 if ((bp = bo->bo_dirty.bv_root) != NULL && 1495 bp->b_lblkno == lblkno && !(bp->b_xflags & BX_BKGRDMARKER)) 1496 return (bp); 1497 if ((bp = bo->bo_clean.bv_root) != NULL) { 1498 bo->bo_clean.bv_root = bp = buf_splay(lblkno, 0, bp); 1499 if (bp->b_lblkno == lblkno && !(bp->b_xflags & BX_BKGRDMARKER)) 1500 return (bp); 1501 } 1502 if ((bp = bo->bo_dirty.bv_root) != NULL) { 1503 bo->bo_dirty.bv_root = bp = buf_splay(lblkno, 0, bp); 1504 if (bp->b_lblkno == lblkno && !(bp->b_xflags & BX_BKGRDMARKER)) 1505 return (bp); 1506 } 1507 return (NULL); 1508 } 1509 1510 /* 1511 * Associate a buffer with a vnode. 1512 */ 1513 void 1514 bgetvp(struct vnode *vp, struct buf *bp) 1515 { 1516 struct bufobj *bo; 1517 1518 bo = &vp->v_bufobj; 1519 ASSERT_BO_LOCKED(bo); 1520 VNASSERT(bp->b_vp == NULL, bp->b_vp, ("bgetvp: not free")); 1521 1522 CTR3(KTR_BUF, "bgetvp(%p) vp %p flags %X", bp, vp, bp->b_flags); 1523 VNASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) == 0, vp, 1524 ("bgetvp: bp already attached! %p", bp)); 1525 1526 vhold(vp); 1527 if (VFS_NEEDSGIANT(vp->v_mount) || bo->bo_flag & BO_NEEDSGIANT) 1528 bp->b_flags |= B_NEEDSGIANT; 1529 bp->b_vp = vp; 1530 bp->b_bufobj = bo; 1531 /* 1532 * Insert onto list for new vnode. 1533 */ 1534 buf_vlist_add(bp, bo, BX_VNCLEAN); 1535 } 1536 1537 /* 1538 * Disassociate a buffer from a vnode. 1539 */ 1540 void 1541 brelvp(struct buf *bp) 1542 { 1543 struct bufobj *bo; 1544 struct vnode *vp; 1545 1546 CTR3(KTR_BUF, "brelvp(%p) vp %p flags %X", bp, bp->b_vp, bp->b_flags); 1547 KASSERT(bp->b_vp != NULL, ("brelvp: NULL")); 1548 1549 /* 1550 * Delete from old vnode list, if on one. 1551 */ 1552 vp = bp->b_vp; /* XXX */ 1553 bo = bp->b_bufobj; 1554 BO_LOCK(bo); 1555 if (bp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN)) 1556 buf_vlist_remove(bp); 1557 else 1558 panic("brelvp: Buffer %p not on queue.", bp); 1559 if ((bo->bo_flag & BO_ONWORKLST) && bo->bo_dirty.bv_cnt == 0) { 1560 bo->bo_flag &= ~BO_ONWORKLST; 1561 mtx_lock(&sync_mtx); 1562 LIST_REMOVE(bo, bo_synclist); 1563 syncer_worklist_len--; 1564 mtx_unlock(&sync_mtx); 1565 } 1566 bp->b_flags &= ~B_NEEDSGIANT; 1567 bp->b_vp = NULL; 1568 bp->b_bufobj = NULL; 1569 BO_UNLOCK(bo); 1570 vdrop(vp); 1571 } 1572 1573 /* 1574 * Add an item to the syncer work queue. 1575 */ 1576 static void 1577 vn_syncer_add_to_worklist(struct bufobj *bo, int delay) 1578 { 1579 int queue, slot; 1580 1581 ASSERT_BO_LOCKED(bo); 1582 1583 mtx_lock(&sync_mtx); 1584 if (bo->bo_flag & BO_ONWORKLST) 1585 LIST_REMOVE(bo, bo_synclist); 1586 else { 1587 bo->bo_flag |= BO_ONWORKLST; 1588 syncer_worklist_len++; 1589 } 1590 1591 if (delay > syncer_maxdelay - 2) 1592 delay = syncer_maxdelay - 2; 1593 slot = (syncer_delayno + delay) & syncer_mask; 1594 1595 queue = VFS_NEEDSGIANT(bo->__bo_vnode->v_mount) ? WI_GIANTQ : 1596 WI_MPSAFEQ; 1597 LIST_INSERT_HEAD(&syncer_workitem_pending[queue][slot], bo, 1598 bo_synclist); 1599 mtx_unlock(&sync_mtx); 1600 } 1601 1602 static int 1603 sysctl_vfs_worklist_len(SYSCTL_HANDLER_ARGS) 1604 { 1605 int error, len; 1606 1607 mtx_lock(&sync_mtx); 1608 len = syncer_worklist_len - sync_vnode_count; 1609 mtx_unlock(&sync_mtx); 1610 error = SYSCTL_OUT(req, &len, sizeof(len)); 1611 return (error); 1612 } 1613 1614 SYSCTL_PROC(_vfs, OID_AUTO, worklist_len, CTLTYPE_INT | CTLFLAG_RD, NULL, 0, 1615 sysctl_vfs_worklist_len, "I", "Syncer thread worklist length"); 1616 1617 static struct proc *updateproc; 1618 static void sched_sync(void); 1619 static struct kproc_desc up_kp = { 1620 "syncer", 1621 sched_sync, 1622 &updateproc 1623 }; 1624 SYSINIT(syncer, SI_SUB_KTHREAD_UPDATE, SI_ORDER_FIRST, kproc_start, &up_kp); 1625 1626 static int 1627 sync_vnode(struct synclist *slp, struct bufobj **bo, struct thread *td) 1628 { 1629 struct vnode *vp; 1630 struct mount *mp; 1631 1632 *bo = LIST_FIRST(slp); 1633 if (*bo == NULL) 1634 return (0); 1635 vp = (*bo)->__bo_vnode; /* XXX */ 1636 if (VOP_ISLOCKED(vp) != 0 || VI_TRYLOCK(vp) == 0) 1637 return (1); 1638 /* 1639 * We use vhold in case the vnode does not 1640 * successfully sync. vhold prevents the vnode from 1641 * going away when we unlock the sync_mtx so that 1642 * we can acquire the vnode interlock. 1643 */ 1644 vholdl(vp); 1645 mtx_unlock(&sync_mtx); 1646 VI_UNLOCK(vp); 1647 if (vn_start_write(vp, &mp, V_NOWAIT) != 0) { 1648 vdrop(vp); 1649 mtx_lock(&sync_mtx); 1650 return (*bo == LIST_FIRST(slp)); 1651 } 1652 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 1653 (void) VOP_FSYNC(vp, MNT_LAZY, td); 1654 VOP_UNLOCK(vp, 0); 1655 vn_finished_write(mp); 1656 BO_LOCK(*bo); 1657 if (((*bo)->bo_flag & BO_ONWORKLST) != 0) { 1658 /* 1659 * Put us back on the worklist. The worklist 1660 * routine will remove us from our current 1661 * position and then add us back in at a later 1662 * position. 1663 */ 1664 vn_syncer_add_to_worklist(*bo, syncdelay); 1665 } 1666 BO_UNLOCK(*bo); 1667 vdrop(vp); 1668 mtx_lock(&sync_mtx); 1669 return (0); 1670 } 1671 1672 /* 1673 * System filesystem synchronizer daemon. 1674 */ 1675 static void 1676 sched_sync(void) 1677 { 1678 struct synclist *gnext, *next; 1679 struct synclist *gslp, *slp; 1680 struct bufobj *bo; 1681 long starttime; 1682 struct thread *td = curthread; 1683 int last_work_seen; 1684 int net_worklist_len; 1685 int syncer_final_iter; 1686 int first_printf; 1687 int error; 1688 1689 last_work_seen = 0; 1690 syncer_final_iter = 0; 1691 first_printf = 1; 1692 syncer_state = SYNCER_RUNNING; 1693 starttime = time_uptime; 1694 td->td_pflags |= TDP_NORUNNINGBUF; 1695 1696 EVENTHANDLER_REGISTER(shutdown_pre_sync, syncer_shutdown, td->td_proc, 1697 SHUTDOWN_PRI_LAST); 1698 1699 mtx_lock(&sync_mtx); 1700 for (;;) { 1701 if (syncer_state == SYNCER_FINAL_DELAY && 1702 syncer_final_iter == 0) { 1703 mtx_unlock(&sync_mtx); 1704 kproc_suspend_check(td->td_proc); 1705 mtx_lock(&sync_mtx); 1706 } 1707 net_worklist_len = syncer_worklist_len - sync_vnode_count; 1708 if (syncer_state != SYNCER_RUNNING && 1709 starttime != time_uptime) { 1710 if (first_printf) { 1711 printf("\nSyncing disks, vnodes remaining..."); 1712 first_printf = 0; 1713 } 1714 printf("%d ", net_worklist_len); 1715 } 1716 starttime = time_uptime; 1717 1718 /* 1719 * Push files whose dirty time has expired. Be careful 1720 * of interrupt race on slp queue. 1721 * 1722 * Skip over empty worklist slots when shutting down. 1723 */ 1724 do { 1725 slp = &syncer_workitem_pending[WI_MPSAFEQ][syncer_delayno]; 1726 gslp = &syncer_workitem_pending[WI_GIANTQ][syncer_delayno]; 1727 syncer_delayno += 1; 1728 if (syncer_delayno == syncer_maxdelay) 1729 syncer_delayno = 0; 1730 next = &syncer_workitem_pending[WI_MPSAFEQ][syncer_delayno]; 1731 gnext = &syncer_workitem_pending[WI_GIANTQ][syncer_delayno]; 1732 /* 1733 * If the worklist has wrapped since the 1734 * it was emptied of all but syncer vnodes, 1735 * switch to the FINAL_DELAY state and run 1736 * for one more second. 1737 */ 1738 if (syncer_state == SYNCER_SHUTTING_DOWN && 1739 net_worklist_len == 0 && 1740 last_work_seen == syncer_delayno) { 1741 syncer_state = SYNCER_FINAL_DELAY; 1742 syncer_final_iter = SYNCER_SHUTDOWN_SPEEDUP; 1743 } 1744 } while (syncer_state != SYNCER_RUNNING && LIST_EMPTY(slp) && 1745 LIST_EMPTY(gslp) && syncer_worklist_len > 0); 1746 1747 /* 1748 * Keep track of the last time there was anything 1749 * on the worklist other than syncer vnodes. 1750 * Return to the SHUTTING_DOWN state if any 1751 * new work appears. 1752 */ 1753 if (net_worklist_len > 0 || syncer_state == SYNCER_RUNNING) 1754 last_work_seen = syncer_delayno; 1755 if (net_worklist_len > 0 && syncer_state == SYNCER_FINAL_DELAY) 1756 syncer_state = SYNCER_SHUTTING_DOWN; 1757 while (!LIST_EMPTY(slp)) { 1758 error = sync_vnode(slp, &bo, td); 1759 if (error == 1) { 1760 LIST_REMOVE(bo, bo_synclist); 1761 LIST_INSERT_HEAD(next, bo, bo_synclist); 1762 continue; 1763 } 1764 } 1765 if (!LIST_EMPTY(gslp)) { 1766 mtx_unlock(&sync_mtx); 1767 mtx_lock(&Giant); 1768 mtx_lock(&sync_mtx); 1769 while (!LIST_EMPTY(gslp)) { 1770 error = sync_vnode(gslp, &bo, td); 1771 if (error == 1) { 1772 LIST_REMOVE(bo, bo_synclist); 1773 LIST_INSERT_HEAD(gnext, bo, 1774 bo_synclist); 1775 continue; 1776 } 1777 } 1778 mtx_unlock(&Giant); 1779 } 1780 if (syncer_state == SYNCER_FINAL_DELAY && syncer_final_iter > 0) 1781 syncer_final_iter--; 1782 /* 1783 * The variable rushjob allows the kernel to speed up the 1784 * processing of the filesystem syncer process. A rushjob 1785 * value of N tells the filesystem syncer to process the next 1786 * N seconds worth of work on its queue ASAP. Currently rushjob 1787 * is used by the soft update code to speed up the filesystem 1788 * syncer process when the incore state is getting so far 1789 * ahead of the disk that the kernel memory pool is being 1790 * threatened with exhaustion. 1791 */ 1792 if (rushjob > 0) { 1793 rushjob -= 1; 1794 continue; 1795 } 1796 /* 1797 * Just sleep for a short period of time between 1798 * iterations when shutting down to allow some I/O 1799 * to happen. 1800 * 1801 * If it has taken us less than a second to process the 1802 * current work, then wait. Otherwise start right over 1803 * again. We can still lose time if any single round 1804 * takes more than two seconds, but it does not really 1805 * matter as we are just trying to generally pace the 1806 * filesystem activity. 1807 */ 1808 if (syncer_state != SYNCER_RUNNING) 1809 cv_timedwait(&sync_wakeup, &sync_mtx, 1810 hz / SYNCER_SHUTDOWN_SPEEDUP); 1811 else if (time_uptime == starttime) 1812 cv_timedwait(&sync_wakeup, &sync_mtx, hz); 1813 } 1814 } 1815 1816 /* 1817 * Request the syncer daemon to speed up its work. 1818 * We never push it to speed up more than half of its 1819 * normal turn time, otherwise it could take over the cpu. 1820 */ 1821 int 1822 speedup_syncer(void) 1823 { 1824 int ret = 0; 1825 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 cv_broadcast(&sync_wakeup); 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 1845 if (howto & RB_NOSYNC) 1846 return; 1847 mtx_lock(&sync_mtx); 1848 syncer_state = SYNCER_SHUTTING_DOWN; 1849 rushjob = 0; 1850 mtx_unlock(&sync_mtx); 1851 cv_broadcast(&sync_wakeup); 1852 kproc_shutdown(arg, howto); 1853 } 1854 1855 /* 1856 * Reassign a buffer from one vnode to another. 1857 * Used to assign file specific control information 1858 * (indirect blocks) to the vnode to which they belong. 1859 */ 1860 void 1861 reassignbuf(struct buf *bp) 1862 { 1863 struct vnode *vp; 1864 struct bufobj *bo; 1865 int delay; 1866 #ifdef INVARIANTS 1867 struct bufv *bv; 1868 #endif 1869 1870 vp = bp->b_vp; 1871 bo = bp->b_bufobj; 1872 ++reassignbufcalls; 1873 1874 CTR3(KTR_BUF, "reassignbuf(%p) vp %p flags %X", 1875 bp, bp->b_vp, bp->b_flags); 1876 /* 1877 * B_PAGING flagged buffers cannot be reassigned because their vp 1878 * is not fully linked in. 1879 */ 1880 if (bp->b_flags & B_PAGING) 1881 panic("cannot reassign paging buffer"); 1882 1883 /* 1884 * Delete from old vnode list, if on one. 1885 */ 1886 BO_LOCK(bo); 1887 if (bp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN)) 1888 buf_vlist_remove(bp); 1889 else 1890 panic("reassignbuf: Buffer %p not on queue.", bp); 1891 /* 1892 * If dirty, put on list of dirty buffers; otherwise insert onto list 1893 * of clean buffers. 1894 */ 1895 if (bp->b_flags & B_DELWRI) { 1896 if ((bo->bo_flag & BO_ONWORKLST) == 0) { 1897 switch (vp->v_type) { 1898 case VDIR: 1899 delay = dirdelay; 1900 break; 1901 case VCHR: 1902 delay = metadelay; 1903 break; 1904 default: 1905 delay = filedelay; 1906 } 1907 vn_syncer_add_to_worklist(bo, delay); 1908 } 1909 buf_vlist_add(bp, bo, BX_VNDIRTY); 1910 } else { 1911 buf_vlist_add(bp, bo, BX_VNCLEAN); 1912 1913 if ((bo->bo_flag & BO_ONWORKLST) && bo->bo_dirty.bv_cnt == 0) { 1914 mtx_lock(&sync_mtx); 1915 LIST_REMOVE(bo, bo_synclist); 1916 syncer_worklist_len--; 1917 mtx_unlock(&sync_mtx); 1918 bo->bo_flag &= ~BO_ONWORKLST; 1919 } 1920 } 1921 #ifdef INVARIANTS 1922 bv = &bo->bo_clean; 1923 bp = TAILQ_FIRST(&bv->bv_hd); 1924 KASSERT(bp == NULL || bp->b_bufobj == bo, 1925 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 1926 bp = TAILQ_LAST(&bv->bv_hd, buflists); 1927 KASSERT(bp == NULL || bp->b_bufobj == bo, 1928 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 1929 bv = &bo->bo_dirty; 1930 bp = TAILQ_FIRST(&bv->bv_hd); 1931 KASSERT(bp == NULL || bp->b_bufobj == bo, 1932 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 1933 bp = TAILQ_LAST(&bv->bv_hd, buflists); 1934 KASSERT(bp == NULL || bp->b_bufobj == bo, 1935 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 1936 #endif 1937 BO_UNLOCK(bo); 1938 } 1939 1940 /* 1941 * Increment the use and hold counts on the vnode, taking care to reference 1942 * the driver's usecount if this is a chardev. The vholdl() will remove 1943 * the vnode from the free list if it is presently free. Requires the 1944 * vnode interlock and returns with it held. 1945 */ 1946 static void 1947 v_incr_usecount(struct vnode *vp) 1948 { 1949 1950 CTR3(KTR_VFS, "v_incr_usecount: vp %p holdcnt %d usecount %d\n", 1951 vp, vp->v_holdcnt, vp->v_usecount); 1952 vp->v_usecount++; 1953 if (vp->v_type == VCHR && vp->v_rdev != NULL) { 1954 dev_lock(); 1955 vp->v_rdev->si_usecount++; 1956 dev_unlock(); 1957 } 1958 vholdl(vp); 1959 } 1960 1961 /* 1962 * Turn a holdcnt into a use+holdcnt such that only one call to 1963 * v_decr_usecount is needed. 1964 */ 1965 static void 1966 v_upgrade_usecount(struct vnode *vp) 1967 { 1968 1969 CTR3(KTR_VFS, "v_upgrade_usecount: vp %p holdcnt %d usecount %d\n", 1970 vp, vp->v_holdcnt, vp->v_usecount); 1971 vp->v_usecount++; 1972 if (vp->v_type == VCHR && vp->v_rdev != NULL) { 1973 dev_lock(); 1974 vp->v_rdev->si_usecount++; 1975 dev_unlock(); 1976 } 1977 } 1978 1979 /* 1980 * Decrement the vnode use and hold count along with the driver's usecount 1981 * if this is a chardev. The vdropl() below releases the vnode interlock 1982 * as it may free the vnode. 1983 */ 1984 static void 1985 v_decr_usecount(struct vnode *vp) 1986 { 1987 1988 CTR3(KTR_VFS, "v_decr_usecount: vp %p holdcnt %d usecount %d\n", 1989 vp, vp->v_holdcnt, vp->v_usecount); 1990 ASSERT_VI_LOCKED(vp, __FUNCTION__); 1991 VNASSERT(vp->v_usecount > 0, vp, 1992 ("v_decr_usecount: negative usecount")); 1993 vp->v_usecount--; 1994 if (vp->v_type == VCHR && vp->v_rdev != NULL) { 1995 dev_lock(); 1996 vp->v_rdev->si_usecount--; 1997 dev_unlock(); 1998 } 1999 vdropl(vp); 2000 } 2001 2002 /* 2003 * Decrement only the use count and driver use count. This is intended to 2004 * be paired with a follow on vdropl() to release the remaining hold count. 2005 * In this way we may vgone() a vnode with a 0 usecount without risk of 2006 * having it end up on a free list because the hold count is kept above 0. 2007 */ 2008 static void 2009 v_decr_useonly(struct vnode *vp) 2010 { 2011 2012 CTR3(KTR_VFS, "v_decr_useonly: vp %p holdcnt %d usecount %d\n", 2013 vp, vp->v_holdcnt, vp->v_usecount); 2014 ASSERT_VI_LOCKED(vp, __FUNCTION__); 2015 VNASSERT(vp->v_usecount > 0, vp, 2016 ("v_decr_useonly: negative usecount")); 2017 vp->v_usecount--; 2018 if (vp->v_type == VCHR && vp->v_rdev != NULL) { 2019 dev_lock(); 2020 vp->v_rdev->si_usecount--; 2021 dev_unlock(); 2022 } 2023 } 2024 2025 /* 2026 * Grab a particular vnode from the free list, increment its 2027 * reference count and lock it. VI_DOOMED is set if the vnode 2028 * is being destroyed. Only callers who specify LK_RETRY will 2029 * see doomed vnodes. If inactive processing was delayed in 2030 * vput try to do it here. 2031 */ 2032 int 2033 vget(struct vnode *vp, int flags, struct thread *td) 2034 { 2035 int error; 2036 2037 error = 0; 2038 VFS_ASSERT_GIANT(vp->v_mount); 2039 VNASSERT((flags & LK_TYPE_MASK) != 0, vp, 2040 ("vget: invalid lock operation")); 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_ELOCKED(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_ELOCKED(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_ELOCKED(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) (panicstr != NULL || (vp) == NULL || \ 3583 (vp)->v_type == VCHR || (vp)->v_type == VBAD) 3584 3585 int vfs_badlock_ddb = 1; /* Drop into debugger on violation. */ 3586 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_ddb, CTLFLAG_RW, &vfs_badlock_ddb, 0, ""); 3587 3588 int vfs_badlock_mutex = 1; /* Check for interlock across VOPs. */ 3589 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_mutex, CTLFLAG_RW, &vfs_badlock_mutex, 0, ""); 3590 3591 int vfs_badlock_print = 1; /* Print lock violations. */ 3592 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_print, CTLFLAG_RW, &vfs_badlock_print, 0, ""); 3593 3594 #ifdef KDB 3595 int vfs_badlock_backtrace = 1; /* Print backtrace at lock violations. */ 3596 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_backtrace, CTLFLAG_RW, &vfs_badlock_backtrace, 0, ""); 3597 #endif 3598 3599 static void 3600 vfs_badlock(const char *msg, const char *str, struct vnode *vp) 3601 { 3602 3603 #ifdef KDB 3604 if (vfs_badlock_backtrace) 3605 kdb_backtrace(); 3606 #endif 3607 if (vfs_badlock_print) 3608 printf("%s: %p %s\n", str, (void *)vp, msg); 3609 if (vfs_badlock_ddb) 3610 kdb_enter(KDB_WHY_VFSLOCK, "lock violation"); 3611 } 3612 3613 void 3614 assert_vi_locked(struct vnode *vp, const char *str) 3615 { 3616 3617 if (vfs_badlock_mutex && !mtx_owned(VI_MTX(vp))) 3618 vfs_badlock("interlock is not locked but should be", str, vp); 3619 } 3620 3621 void 3622 assert_vi_unlocked(struct vnode *vp, const char *str) 3623 { 3624 3625 if (vfs_badlock_mutex && mtx_owned(VI_MTX(vp))) 3626 vfs_badlock("interlock is locked but should not be", str, vp); 3627 } 3628 3629 void 3630 assert_vop_locked(struct vnode *vp, const char *str) 3631 { 3632 3633 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) == 0) 3634 vfs_badlock("is not locked but should be", str, vp); 3635 } 3636 3637 void 3638 assert_vop_unlocked(struct vnode *vp, const char *str) 3639 { 3640 3641 if (!IGNORE_LOCK(vp) && 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 (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) != LK_EXCLUSIVE) 3650 vfs_badlock("is not exclusive locked but should be", str, vp); 3651 } 3652 3653 #if 0 3654 void 3655 assert_vop_elocked_other(struct vnode *vp, const char *str) 3656 { 3657 3658 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) != LK_EXCLOTHER) 3659 vfs_badlock("is not exclusive locked by another thread", 3660 str, vp); 3661 } 3662 3663 void 3664 assert_vop_slocked(struct vnode *vp, const char *str) 3665 { 3666 3667 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) != LK_SHARED) 3668 vfs_badlock("is not locked shared but should be", str, vp); 3669 } 3670 #endif /* 0 */ 3671 #endif /* DEBUG_VFS_LOCKS */ 3672 3673 void 3674 vop_rename_pre(void *ap) 3675 { 3676 struct vop_rename_args *a = ap; 3677 3678 #ifdef DEBUG_VFS_LOCKS 3679 if (a->a_tvp) 3680 ASSERT_VI_UNLOCKED(a->a_tvp, "VOP_RENAME"); 3681 ASSERT_VI_UNLOCKED(a->a_tdvp, "VOP_RENAME"); 3682 ASSERT_VI_UNLOCKED(a->a_fvp, "VOP_RENAME"); 3683 ASSERT_VI_UNLOCKED(a->a_fdvp, "VOP_RENAME"); 3684 3685 /* Check the source (from). */ 3686 if (a->a_tdvp != a->a_fdvp && a->a_tvp != a->a_fdvp) 3687 ASSERT_VOP_UNLOCKED(a->a_fdvp, "vop_rename: fdvp locked"); 3688 if (a->a_tvp != a->a_fvp) 3689 ASSERT_VOP_UNLOCKED(a->a_fvp, "vop_rename: fvp locked"); 3690 3691 /* Check the target. */ 3692 if (a->a_tvp) 3693 ASSERT_VOP_LOCKED(a->a_tvp, "vop_rename: tvp not locked"); 3694 ASSERT_VOP_LOCKED(a->a_tdvp, "vop_rename: tdvp not locked"); 3695 #endif 3696 if (a->a_tdvp != a->a_fdvp) 3697 vhold(a->a_fdvp); 3698 if (a->a_tvp != a->a_fvp) 3699 vhold(a->a_fvp); 3700 vhold(a->a_tdvp); 3701 if (a->a_tvp) 3702 vhold(a->a_tvp); 3703 } 3704 3705 void 3706 vop_strategy_pre(void *ap) 3707 { 3708 #ifdef DEBUG_VFS_LOCKS 3709 struct vop_strategy_args *a; 3710 struct buf *bp; 3711 3712 a = ap; 3713 bp = a->a_bp; 3714 3715 /* 3716 * Cluster ops lock their component buffers but not the IO container. 3717 */ 3718 if ((bp->b_flags & B_CLUSTER) != 0) 3719 return; 3720 3721 if (!BUF_ISLOCKED(bp)) { 3722 if (vfs_badlock_print) 3723 printf( 3724 "VOP_STRATEGY: bp is not locked but should be\n"); 3725 if (vfs_badlock_ddb) 3726 kdb_enter(KDB_WHY_VFSLOCK, "lock violation"); 3727 } 3728 #endif 3729 } 3730 3731 void 3732 vop_lookup_pre(void *ap) 3733 { 3734 #ifdef DEBUG_VFS_LOCKS 3735 struct vop_lookup_args *a; 3736 struct vnode *dvp; 3737 3738 a = ap; 3739 dvp = a->a_dvp; 3740 ASSERT_VI_UNLOCKED(dvp, "VOP_LOOKUP"); 3741 ASSERT_VOP_LOCKED(dvp, "VOP_LOOKUP"); 3742 #endif 3743 } 3744 3745 void 3746 vop_lookup_post(void *ap, int rc) 3747 { 3748 #ifdef DEBUG_VFS_LOCKS 3749 struct vop_lookup_args *a; 3750 struct vnode *dvp; 3751 struct vnode *vp; 3752 3753 a = ap; 3754 dvp = a->a_dvp; 3755 vp = *(a->a_vpp); 3756 3757 ASSERT_VI_UNLOCKED(dvp, "VOP_LOOKUP"); 3758 ASSERT_VOP_LOCKED(dvp, "VOP_LOOKUP"); 3759 3760 if (!rc) 3761 ASSERT_VOP_LOCKED(vp, "VOP_LOOKUP (child)"); 3762 #endif 3763 } 3764 3765 void 3766 vop_lock_pre(void *ap) 3767 { 3768 #ifdef DEBUG_VFS_LOCKS 3769 struct vop_lock1_args *a = ap; 3770 3771 if ((a->a_flags & LK_INTERLOCK) == 0) 3772 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_LOCK"); 3773 else 3774 ASSERT_VI_LOCKED(a->a_vp, "VOP_LOCK"); 3775 #endif 3776 } 3777 3778 void 3779 vop_lock_post(void *ap, int rc) 3780 { 3781 #ifdef DEBUG_VFS_LOCKS 3782 struct vop_lock1_args *a = ap; 3783 3784 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_LOCK"); 3785 if (rc == 0) 3786 ASSERT_VOP_LOCKED(a->a_vp, "VOP_LOCK"); 3787 #endif 3788 } 3789 3790 void 3791 vop_unlock_pre(void *ap) 3792 { 3793 #ifdef DEBUG_VFS_LOCKS 3794 struct vop_unlock_args *a = ap; 3795 3796 if (a->a_flags & LK_INTERLOCK) 3797 ASSERT_VI_LOCKED(a->a_vp, "VOP_UNLOCK"); 3798 ASSERT_VOP_LOCKED(a->a_vp, "VOP_UNLOCK"); 3799 #endif 3800 } 3801 3802 void 3803 vop_unlock_post(void *ap, int rc) 3804 { 3805 #ifdef DEBUG_VFS_LOCKS 3806 struct vop_unlock_args *a = ap; 3807 3808 if (a->a_flags & LK_INTERLOCK) 3809 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_UNLOCK"); 3810 #endif 3811 } 3812 3813 void 3814 vop_create_post(void *ap, int rc) 3815 { 3816 struct vop_create_args *a = ap; 3817 3818 if (!rc) 3819 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 3820 } 3821 3822 void 3823 vop_link_post(void *ap, int rc) 3824 { 3825 struct vop_link_args *a = ap; 3826 3827 if (!rc) { 3828 VFS_KNOTE_LOCKED(a->a_vp, NOTE_LINK); 3829 VFS_KNOTE_LOCKED(a->a_tdvp, NOTE_WRITE); 3830 } 3831 } 3832 3833 void 3834 vop_mkdir_post(void *ap, int rc) 3835 { 3836 struct vop_mkdir_args *a = ap; 3837 3838 if (!rc) 3839 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE | NOTE_LINK); 3840 } 3841 3842 void 3843 vop_mknod_post(void *ap, int rc) 3844 { 3845 struct vop_mknod_args *a = ap; 3846 3847 if (!rc) 3848 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 3849 } 3850 3851 void 3852 vop_remove_post(void *ap, int rc) 3853 { 3854 struct vop_remove_args *a = ap; 3855 3856 if (!rc) { 3857 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 3858 VFS_KNOTE_LOCKED(a->a_vp, NOTE_DELETE); 3859 } 3860 } 3861 3862 void 3863 vop_rename_post(void *ap, int rc) 3864 { 3865 struct vop_rename_args *a = ap; 3866 3867 if (!rc) { 3868 VFS_KNOTE_UNLOCKED(a->a_fdvp, NOTE_WRITE); 3869 VFS_KNOTE_UNLOCKED(a->a_tdvp, NOTE_WRITE); 3870 VFS_KNOTE_UNLOCKED(a->a_fvp, NOTE_RENAME); 3871 if (a->a_tvp) 3872 VFS_KNOTE_UNLOCKED(a->a_tvp, NOTE_DELETE); 3873 } 3874 if (a->a_tdvp != a->a_fdvp) 3875 vdrop(a->a_fdvp); 3876 if (a->a_tvp != a->a_fvp) 3877 vdrop(a->a_fvp); 3878 vdrop(a->a_tdvp); 3879 if (a->a_tvp) 3880 vdrop(a->a_tvp); 3881 } 3882 3883 void 3884 vop_rmdir_post(void *ap, int rc) 3885 { 3886 struct vop_rmdir_args *a = ap; 3887 3888 if (!rc) { 3889 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE | NOTE_LINK); 3890 VFS_KNOTE_LOCKED(a->a_vp, NOTE_DELETE); 3891 } 3892 } 3893 3894 void 3895 vop_setattr_post(void *ap, int rc) 3896 { 3897 struct vop_setattr_args *a = ap; 3898 3899 if (!rc) 3900 VFS_KNOTE_LOCKED(a->a_vp, NOTE_ATTRIB); 3901 } 3902 3903 void 3904 vop_symlink_post(void *ap, int rc) 3905 { 3906 struct vop_symlink_args *a = ap; 3907 3908 if (!rc) 3909 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 3910 } 3911 3912 static struct knlist fs_knlist; 3913 3914 static void 3915 vfs_event_init(void *arg) 3916 { 3917 knlist_init(&fs_knlist, NULL, NULL, NULL, NULL); 3918 } 3919 /* XXX - correct order? */ 3920 SYSINIT(vfs_knlist, SI_SUB_VFS, SI_ORDER_ANY, vfs_event_init, NULL); 3921 3922 void 3923 vfs_event_signal(fsid_t *fsid, u_int32_t event, intptr_t data __unused) 3924 { 3925 3926 KNOTE_UNLOCKED(&fs_knlist, event); 3927 } 3928 3929 static int filt_fsattach(struct knote *kn); 3930 static void filt_fsdetach(struct knote *kn); 3931 static int filt_fsevent(struct knote *kn, long hint); 3932 3933 struct filterops fs_filtops = 3934 { 0, filt_fsattach, filt_fsdetach, filt_fsevent }; 3935 3936 static int 3937 filt_fsattach(struct knote *kn) 3938 { 3939 3940 kn->kn_flags |= EV_CLEAR; 3941 knlist_add(&fs_knlist, kn, 0); 3942 return (0); 3943 } 3944 3945 static void 3946 filt_fsdetach(struct knote *kn) 3947 { 3948 3949 knlist_remove(&fs_knlist, kn, 0); 3950 } 3951 3952 static int 3953 filt_fsevent(struct knote *kn, long hint) 3954 { 3955 3956 kn->kn_fflags |= hint; 3957 return (kn->kn_fflags != 0); 3958 } 3959 3960 static int 3961 sysctl_vfs_ctl(SYSCTL_HANDLER_ARGS) 3962 { 3963 struct vfsidctl vc; 3964 int error; 3965 struct mount *mp; 3966 3967 error = SYSCTL_IN(req, &vc, sizeof(vc)); 3968 if (error) 3969 return (error); 3970 if (vc.vc_vers != VFS_CTL_VERS1) 3971 return (EINVAL); 3972 mp = vfs_getvfs(&vc.vc_fsid); 3973 if (mp == NULL) 3974 return (ENOENT); 3975 /* ensure that a specific sysctl goes to the right filesystem. */ 3976 if (strcmp(vc.vc_fstypename, "*") != 0 && 3977 strcmp(vc.vc_fstypename, mp->mnt_vfc->vfc_name) != 0) { 3978 vfs_rel(mp); 3979 return (EINVAL); 3980 } 3981 VCTLTOREQ(&vc, req); 3982 error = VFS_SYSCTL(mp, vc.vc_op, req); 3983 vfs_rel(mp); 3984 return (error); 3985 } 3986 3987 SYSCTL_PROC(_vfs, OID_AUTO, ctl, CTLFLAG_WR, NULL, 0, sysctl_vfs_ctl, "", 3988 "Sysctl by fsid"); 3989 3990 /* 3991 * Function to initialize a va_filerev field sensibly. 3992 * XXX: Wouldn't a random number make a lot more sense ?? 3993 */ 3994 u_quad_t 3995 init_va_filerev(void) 3996 { 3997 struct bintime bt; 3998 3999 getbinuptime(&bt); 4000 return (((u_quad_t)bt.sec << 32LL) | (bt.frac >> 32LL)); 4001 } 4002 4003 static int filt_vfsread(struct knote *kn, long hint); 4004 static int filt_vfswrite(struct knote *kn, long hint); 4005 static int filt_vfsvnode(struct knote *kn, long hint); 4006 static void filt_vfsdetach(struct knote *kn); 4007 static struct filterops vfsread_filtops = 4008 { 1, NULL, filt_vfsdetach, filt_vfsread }; 4009 static struct filterops vfswrite_filtops = 4010 { 1, NULL, filt_vfsdetach, filt_vfswrite }; 4011 static struct filterops vfsvnode_filtops = 4012 { 1, NULL, filt_vfsdetach, filt_vfsvnode }; 4013 4014 static void 4015 vfs_knllock(void *arg) 4016 { 4017 struct vnode *vp = arg; 4018 4019 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 4020 } 4021 4022 static void 4023 vfs_knlunlock(void *arg) 4024 { 4025 struct vnode *vp = arg; 4026 4027 VOP_UNLOCK(vp, 0); 4028 } 4029 4030 static int 4031 vfs_knllocked(void *arg) 4032 { 4033 struct vnode *vp = arg; 4034 4035 return (VOP_ISLOCKED(vp) == LK_EXCLUSIVE); 4036 } 4037 4038 int 4039 vfs_kqfilter(struct vop_kqfilter_args *ap) 4040 { 4041 struct vnode *vp = ap->a_vp; 4042 struct knote *kn = ap->a_kn; 4043 struct knlist *knl; 4044 4045 switch (kn->kn_filter) { 4046 case EVFILT_READ: 4047 kn->kn_fop = &vfsread_filtops; 4048 break; 4049 case EVFILT_WRITE: 4050 kn->kn_fop = &vfswrite_filtops; 4051 break; 4052 case EVFILT_VNODE: 4053 kn->kn_fop = &vfsvnode_filtops; 4054 break; 4055 default: 4056 return (EINVAL); 4057 } 4058 4059 kn->kn_hook = (caddr_t)vp; 4060 4061 if (vp->v_pollinfo == NULL) 4062 v_addpollinfo(vp); 4063 if (vp->v_pollinfo == NULL) 4064 return (ENOMEM); 4065 knl = &vp->v_pollinfo->vpi_selinfo.si_note; 4066 knlist_add(knl, kn, 0); 4067 4068 return (0); 4069 } 4070 4071 /* 4072 * Detach knote from vnode 4073 */ 4074 static void 4075 filt_vfsdetach(struct knote *kn) 4076 { 4077 struct vnode *vp = (struct vnode *)kn->kn_hook; 4078 4079 KASSERT(vp->v_pollinfo != NULL, ("Missing v_pollinfo")); 4080 knlist_remove(&vp->v_pollinfo->vpi_selinfo.si_note, kn, 0); 4081 } 4082 4083 /*ARGSUSED*/ 4084 static int 4085 filt_vfsread(struct knote *kn, long hint) 4086 { 4087 struct vnode *vp = (struct vnode *)kn->kn_hook; 4088 struct vattr va; 4089 4090 /* 4091 * filesystem is gone, so set the EOF flag and schedule 4092 * the knote for deletion. 4093 */ 4094 if (hint == NOTE_REVOKE) { 4095 kn->kn_flags |= (EV_EOF | EV_ONESHOT); 4096 return (1); 4097 } 4098 4099 if (VOP_GETATTR(vp, &va, curthread->td_ucred, curthread)) 4100 return (0); 4101 4102 kn->kn_data = va.va_size - kn->kn_fp->f_offset; 4103 return (kn->kn_data != 0); 4104 } 4105 4106 /*ARGSUSED*/ 4107 static int 4108 filt_vfswrite(struct knote *kn, long hint) 4109 { 4110 /* 4111 * filesystem is gone, so set the EOF flag and schedule 4112 * the knote for deletion. 4113 */ 4114 if (hint == NOTE_REVOKE) 4115 kn->kn_flags |= (EV_EOF | EV_ONESHOT); 4116 4117 kn->kn_data = 0; 4118 return (1); 4119 } 4120 4121 static int 4122 filt_vfsvnode(struct knote *kn, long hint) 4123 { 4124 if (kn->kn_sfflags & hint) 4125 kn->kn_fflags |= hint; 4126 if (hint == NOTE_REVOKE) { 4127 kn->kn_flags |= EV_EOF; 4128 return (1); 4129 } 4130 return (kn->kn_fflags != 0); 4131 } 4132 4133 int 4134 vfs_read_dirent(struct vop_readdir_args *ap, struct dirent *dp, off_t off) 4135 { 4136 int error; 4137 4138 if (dp->d_reclen > ap->a_uio->uio_resid) 4139 return (ENAMETOOLONG); 4140 error = uiomove(dp, dp->d_reclen, ap->a_uio); 4141 if (error) { 4142 if (ap->a_ncookies != NULL) { 4143 if (ap->a_cookies != NULL) 4144 free(ap->a_cookies, M_TEMP); 4145 ap->a_cookies = NULL; 4146 *ap->a_ncookies = 0; 4147 } 4148 return (error); 4149 } 4150 if (ap->a_ncookies == NULL) 4151 return (0); 4152 4153 KASSERT(ap->a_cookies, 4154 ("NULL ap->a_cookies value with non-NULL ap->a_ncookies!")); 4155 4156 *ap->a_cookies = realloc(*ap->a_cookies, 4157 (*ap->a_ncookies + 1) * sizeof(u_long), M_TEMP, M_WAITOK | M_ZERO); 4158 (*ap->a_cookies)[*ap->a_ncookies] = off; 4159 return (0); 4160 } 4161 4162 /* 4163 * Mark for update the access time of the file if the filesystem 4164 * supports VA_MARK_ATIME. This functionality is used by execve 4165 * and mmap, so we want to avoid the synchronous I/O implied by 4166 * directly setting va_atime for the sake of efficiency. 4167 */ 4168 void 4169 vfs_mark_atime(struct vnode *vp, struct thread *td) 4170 { 4171 struct vattr atimeattr; 4172 4173 if ((vp->v_mount->mnt_flag & (MNT_NOATIME | MNT_RDONLY)) == 0) { 4174 VATTR_NULL(&atimeattr); 4175 atimeattr.va_vaflags |= VA_MARK_ATIME; 4176 (void)VOP_SETATTR(vp, &atimeattr, td->td_ucred, td); 4177 } 4178 } 4179