vfs_subr.c revision 284993
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: stable/10/sys/kern/vfs_subr.c 284993 2015-07-01 06:54:25Z kib $"); 43 44#include "opt_compat.h" 45#include "opt_ddb.h" 46#include "opt_watchdog.h" 47 48#include <sys/param.h> 49#include <sys/systm.h> 50#include <sys/bio.h> 51#include <sys/buf.h> 52#include <sys/condvar.h> 53#include <sys/conf.h> 54#include <sys/dirent.h> 55#include <sys/event.h> 56#include <sys/eventhandler.h> 57#include <sys/extattr.h> 58#include <sys/file.h> 59#include <sys/fcntl.h> 60#include <sys/jail.h> 61#include <sys/kdb.h> 62#include <sys/kernel.h> 63#include <sys/kthread.h> 64#include <sys/lockf.h> 65#include <sys/malloc.h> 66#include <sys/mount.h> 67#include <sys/namei.h> 68#include <sys/pctrie.h> 69#include <sys/priv.h> 70#include <sys/reboot.h> 71#include <sys/rwlock.h> 72#include <sys/sched.h> 73#include <sys/sleepqueue.h> 74#include <sys/smp.h> 75#include <sys/stat.h> 76#include <sys/sysctl.h> 77#include <sys/syslog.h> 78#include <sys/vmmeter.h> 79#include <sys/vnode.h> 80#include <sys/watchdog.h> 81 82#include <machine/stdarg.h> 83 84#include <security/mac/mac_framework.h> 85 86#include <vm/vm.h> 87#include <vm/vm_object.h> 88#include <vm/vm_extern.h> 89#include <vm/pmap.h> 90#include <vm/vm_map.h> 91#include <vm/vm_page.h> 92#include <vm/vm_kern.h> 93#include <vm/uma.h> 94 95#ifdef DDB 96#include <ddb/ddb.h> 97#endif 98 99static void delmntque(struct vnode *vp); 100static int flushbuflist(struct bufv *bufv, int flags, struct bufobj *bo, 101 int slpflag, int slptimeo); 102static void syncer_shutdown(void *arg, int howto); 103static int vtryrecycle(struct vnode *vp); 104static void v_incr_usecount(struct vnode *); 105static void v_decr_usecount(struct vnode *); 106static void v_decr_useonly(struct vnode *); 107static void v_upgrade_usecount(struct vnode *); 108static void vnlru_free(int); 109static void vgonel(struct vnode *); 110static void vfs_knllock(void *arg); 111static void vfs_knlunlock(void *arg); 112static void vfs_knl_assert_locked(void *arg); 113static void vfs_knl_assert_unlocked(void *arg); 114static void destroy_vpollinfo(struct vpollinfo *vi); 115 116/* 117 * Number of vnodes in existence. Increased whenever getnewvnode() 118 * allocates a new vnode, decreased in vdropl() for VI_DOOMED vnode. 119 */ 120static unsigned long numvnodes; 121 122SYSCTL_ULONG(_vfs, OID_AUTO, numvnodes, CTLFLAG_RD, &numvnodes, 0, 123 "Number of vnodes in existence"); 124 125static u_long vnodes_created; 126SYSCTL_ULONG(_vfs, OID_AUTO, vnodes_created, CTLFLAG_RD, &vnodes_created, 127 0, "Number of vnodes created by getnewvnode"); 128 129/* 130 * Conversion tables for conversion from vnode types to inode formats 131 * and back. 132 */ 133enum vtype iftovt_tab[16] = { 134 VNON, VFIFO, VCHR, VNON, VDIR, VNON, VBLK, VNON, 135 VREG, VNON, VLNK, VNON, VSOCK, VNON, VNON, VBAD, 136}; 137int vttoif_tab[10] = { 138 0, S_IFREG, S_IFDIR, S_IFBLK, S_IFCHR, S_IFLNK, 139 S_IFSOCK, S_IFIFO, S_IFMT, S_IFMT 140}; 141 142/* 143 * List of vnodes that are ready for recycling. 144 */ 145static TAILQ_HEAD(freelst, vnode) vnode_free_list; 146 147/* 148 * Free vnode target. Free vnodes may simply be files which have been stat'd 149 * but not read. This is somewhat common, and a small cache of such files 150 * should be kept to avoid recreation costs. 151 */ 152static u_long wantfreevnodes; 153SYSCTL_ULONG(_vfs, OID_AUTO, wantfreevnodes, CTLFLAG_RW, &wantfreevnodes, 0, ""); 154/* Number of vnodes in the free list. */ 155static u_long freevnodes; 156SYSCTL_ULONG(_vfs, OID_AUTO, freevnodes, CTLFLAG_RD, &freevnodes, 0, 157 "Number of vnodes in the free list"); 158 159static int vlru_allow_cache_src; 160SYSCTL_INT(_vfs, OID_AUTO, vlru_allow_cache_src, CTLFLAG_RW, 161 &vlru_allow_cache_src, 0, "Allow vlru to reclaim source vnode"); 162 163static u_long recycles_count; 164SYSCTL_ULONG(_vfs, OID_AUTO, recycles, CTLFLAG_RD, &recycles_count, 0, 165 "Number of vnodes recycled to avoid exceding kern.maxvnodes"); 166 167/* 168 * Various variables used for debugging the new implementation of 169 * reassignbuf(). 170 * XXX these are probably of (very) limited utility now. 171 */ 172static int reassignbufcalls; 173SYSCTL_INT(_vfs, OID_AUTO, reassignbufcalls, CTLFLAG_RW, &reassignbufcalls, 0, 174 "Number of calls to reassignbuf"); 175 176static u_long free_owe_inact; 177SYSCTL_ULONG(_vfs, OID_AUTO, free_owe_inact, CTLFLAG_RD, &free_owe_inact, 0, 178 "Number of times free vnodes kept on active list due to VFS " 179 "owing inactivation"); 180 181/* 182 * Cache for the mount type id assigned to NFS. This is used for 183 * special checks in nfs/nfs_nqlease.c and vm/vnode_pager.c. 184 */ 185int nfs_mount_type = -1; 186 187/* To keep more than one thread at a time from running vfs_getnewfsid */ 188static struct mtx mntid_mtx; 189 190/* 191 * Lock for any access to the following: 192 * vnode_free_list 193 * numvnodes 194 * freevnodes 195 */ 196static struct mtx vnode_free_list_mtx; 197 198/* Publicly exported FS */ 199struct nfs_public nfs_pub; 200 201static uma_zone_t buf_trie_zone; 202 203/* Zone for allocation of new vnodes - used exclusively by getnewvnode() */ 204static uma_zone_t vnode_zone; 205static uma_zone_t vnodepoll_zone; 206 207/* 208 * The workitem queue. 209 * 210 * It is useful to delay writes of file data and filesystem metadata 211 * for tens of seconds so that quickly created and deleted files need 212 * not waste disk bandwidth being created and removed. To realize this, 213 * we append vnodes to a "workitem" queue. When running with a soft 214 * updates implementation, most pending metadata dependencies should 215 * not wait for more than a few seconds. Thus, mounted on block devices 216 * are delayed only about a half the time that file data is delayed. 217 * Similarly, directory updates are more critical, so are only delayed 218 * about a third the time that file data is delayed. Thus, there are 219 * SYNCER_MAXDELAY queues that are processed round-robin at a rate of 220 * one each second (driven off the filesystem syncer process). The 221 * syncer_delayno variable indicates the next queue that is to be processed. 222 * Items that need to be processed soon are placed in this queue: 223 * 224 * syncer_workitem_pending[syncer_delayno] 225 * 226 * A delay of fifteen seconds is done by placing the request fifteen 227 * entries later in the queue: 228 * 229 * syncer_workitem_pending[(syncer_delayno + 15) & syncer_mask] 230 * 231 */ 232static int syncer_delayno; 233static long syncer_mask; 234LIST_HEAD(synclist, bufobj); 235static struct synclist *syncer_workitem_pending; 236/* 237 * The sync_mtx protects: 238 * bo->bo_synclist 239 * sync_vnode_count 240 * syncer_delayno 241 * syncer_state 242 * syncer_workitem_pending 243 * syncer_worklist_len 244 * rushjob 245 */ 246static struct mtx sync_mtx; 247static struct cv sync_wakeup; 248 249#define SYNCER_MAXDELAY 32 250static int syncer_maxdelay = SYNCER_MAXDELAY; /* maximum delay time */ 251static int syncdelay = 30; /* max time to delay syncing data */ 252static int filedelay = 30; /* time to delay syncing files */ 253SYSCTL_INT(_kern, OID_AUTO, filedelay, CTLFLAG_RW, &filedelay, 0, 254 "Time to delay syncing files (in seconds)"); 255static int dirdelay = 29; /* time to delay syncing directories */ 256SYSCTL_INT(_kern, OID_AUTO, dirdelay, CTLFLAG_RW, &dirdelay, 0, 257 "Time to delay syncing directories (in seconds)"); 258static int metadelay = 28; /* time to delay syncing metadata */ 259SYSCTL_INT(_kern, OID_AUTO, metadelay, CTLFLAG_RW, &metadelay, 0, 260 "Time to delay syncing metadata (in seconds)"); 261static int rushjob; /* number of slots to run ASAP */ 262static int stat_rush_requests; /* number of times I/O speeded up */ 263SYSCTL_INT(_debug, OID_AUTO, rush_requests, CTLFLAG_RW, &stat_rush_requests, 0, 264 "Number of times I/O speeded up (rush requests)"); 265 266/* 267 * When shutting down the syncer, run it at four times normal speed. 268 */ 269#define SYNCER_SHUTDOWN_SPEEDUP 4 270static int sync_vnode_count; 271static int syncer_worklist_len; 272static enum { SYNCER_RUNNING, SYNCER_SHUTTING_DOWN, SYNCER_FINAL_DELAY } 273 syncer_state; 274 275/* 276 * Number of vnodes we want to exist at any one time. This is mostly used 277 * to size hash tables in vnode-related code. It is normally not used in 278 * getnewvnode(), as wantfreevnodes is normally nonzero.) 279 * 280 * XXX desiredvnodes is historical cruft and should not exist. 281 */ 282int desiredvnodes; 283SYSCTL_INT(_kern, KERN_MAXVNODES, maxvnodes, CTLFLAG_RW, 284 &desiredvnodes, 0, "Maximum number of vnodes"); 285SYSCTL_ULONG(_kern, OID_AUTO, minvnodes, CTLFLAG_RW, 286 &wantfreevnodes, 0, "Minimum number of vnodes (legacy)"); 287static int vnlru_nowhere; 288SYSCTL_INT(_debug, OID_AUTO, vnlru_nowhere, CTLFLAG_RW, 289 &vnlru_nowhere, 0, "Number of times the vnlru process ran without success"); 290 291/* Shift count for (uintptr_t)vp to initialize vp->v_hash. */ 292static int vnsz2log; 293 294/* 295 * Support for the bufobj clean & dirty pctrie. 296 */ 297static void * 298buf_trie_alloc(struct pctrie *ptree) 299{ 300 301 return uma_zalloc(buf_trie_zone, M_NOWAIT); 302} 303 304static void 305buf_trie_free(struct pctrie *ptree, void *node) 306{ 307 308 uma_zfree(buf_trie_zone, node); 309} 310PCTRIE_DEFINE(BUF, buf, b_lblkno, buf_trie_alloc, buf_trie_free); 311 312/* 313 * Initialize the vnode management data structures. 314 * 315 * Reevaluate the following cap on the number of vnodes after the physical 316 * memory size exceeds 512GB. In the limit, as the physical memory size 317 * grows, the ratio of physical pages to vnodes approaches sixteen to one. 318 */ 319#ifndef MAXVNODES_MAX 320#define MAXVNODES_MAX (512 * (1024 * 1024 * 1024 / (int)PAGE_SIZE / 16)) 321#endif 322static void 323vntblinit(void *dummy __unused) 324{ 325 u_int i; 326 int physvnodes, virtvnodes; 327 328 /* 329 * Desiredvnodes is a function of the physical memory size and the 330 * kernel's heap size. Generally speaking, it scales with the 331 * physical memory size. The ratio of desiredvnodes to physical pages 332 * is one to four until desiredvnodes exceeds 98,304. Thereafter, the 333 * marginal ratio of desiredvnodes to physical pages is one to 334 * sixteen. However, desiredvnodes is limited by the kernel's heap 335 * size. The memory required by desiredvnodes vnodes and vm objects 336 * may not exceed one seventh of the kernel's heap size. 337 */ 338 physvnodes = maxproc + cnt.v_page_count / 16 + 3 * min(98304 * 4, 339 cnt.v_page_count) / 16; 340 virtvnodes = vm_kmem_size / (7 * (sizeof(struct vm_object) + 341 sizeof(struct vnode))); 342 desiredvnodes = min(physvnodes, virtvnodes); 343 if (desiredvnodes > MAXVNODES_MAX) { 344 if (bootverbose) 345 printf("Reducing kern.maxvnodes %d -> %d\n", 346 desiredvnodes, MAXVNODES_MAX); 347 desiredvnodes = MAXVNODES_MAX; 348 } 349 wantfreevnodes = desiredvnodes / 4; 350 mtx_init(&mntid_mtx, "mntid", NULL, MTX_DEF); 351 TAILQ_INIT(&vnode_free_list); 352 mtx_init(&vnode_free_list_mtx, "vnode_free_list", NULL, MTX_DEF); 353 vnode_zone = uma_zcreate("VNODE", sizeof (struct vnode), NULL, NULL, 354 NULL, NULL, UMA_ALIGN_PTR, 0); 355 vnodepoll_zone = uma_zcreate("VNODEPOLL", sizeof (struct vpollinfo), 356 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); 357 /* 358 * Preallocate enough nodes to support one-per buf so that 359 * we can not fail an insert. reassignbuf() callers can not 360 * tolerate the insertion failure. 361 */ 362 buf_trie_zone = uma_zcreate("BUF TRIE", pctrie_node_size(), 363 NULL, NULL, pctrie_zone_init, NULL, UMA_ALIGN_PTR, 364 UMA_ZONE_NOFREE | UMA_ZONE_VM); 365 uma_prealloc(buf_trie_zone, nbuf); 366 /* 367 * Initialize the filesystem syncer. 368 */ 369 syncer_workitem_pending = hashinit(syncer_maxdelay, M_VNODE, 370 &syncer_mask); 371 syncer_maxdelay = syncer_mask + 1; 372 mtx_init(&sync_mtx, "Syncer mtx", NULL, MTX_DEF); 373 cv_init(&sync_wakeup, "syncer"); 374 for (i = 1; i <= sizeof(struct vnode); i <<= 1) 375 vnsz2log++; 376 vnsz2log--; 377} 378SYSINIT(vfs, SI_SUB_VFS, SI_ORDER_FIRST, vntblinit, NULL); 379 380 381/* 382 * Mark a mount point as busy. Used to synchronize access and to delay 383 * unmounting. Eventually, mountlist_mtx is not released on failure. 384 * 385 * vfs_busy() is a custom lock, it can block the caller. 386 * vfs_busy() only sleeps if the unmount is active on the mount point. 387 * For a mountpoint mp, vfs_busy-enforced lock is before lock of any 388 * vnode belonging to mp. 389 * 390 * Lookup uses vfs_busy() to traverse mount points. 391 * root fs var fs 392 * / vnode lock A / vnode lock (/var) D 393 * /var vnode lock B /log vnode lock(/var/log) E 394 * vfs_busy lock C vfs_busy lock F 395 * 396 * Within each file system, the lock order is C->A->B and F->D->E. 397 * 398 * When traversing across mounts, the system follows that lock order: 399 * 400 * C->A->B 401 * | 402 * +->F->D->E 403 * 404 * The lookup() process for namei("/var") illustrates the process: 405 * VOP_LOOKUP() obtains B while A is held 406 * vfs_busy() obtains a shared lock on F while A and B are held 407 * vput() releases lock on B 408 * vput() releases lock on A 409 * VFS_ROOT() obtains lock on D while shared lock on F is held 410 * vfs_unbusy() releases shared lock on F 411 * vn_lock() obtains lock on deadfs vnode vp_crossmp instead of A. 412 * Attempt to lock A (instead of vp_crossmp) while D is held would 413 * violate the global order, causing deadlocks. 414 * 415 * dounmount() locks B while F is drained. 416 */ 417int 418vfs_busy(struct mount *mp, int flags) 419{ 420 421 MPASS((flags & ~MBF_MASK) == 0); 422 CTR3(KTR_VFS, "%s: mp %p with flags %d", __func__, mp, flags); 423 424 MNT_ILOCK(mp); 425 MNT_REF(mp); 426 /* 427 * If mount point is currenly being unmounted, sleep until the 428 * mount point fate is decided. If thread doing the unmounting fails, 429 * it will clear MNTK_UNMOUNT flag before waking us up, indicating 430 * that this mount point has survived the unmount attempt and vfs_busy 431 * should retry. Otherwise the unmounter thread will set MNTK_REFEXPIRE 432 * flag in addition to MNTK_UNMOUNT, indicating that mount point is 433 * about to be really destroyed. vfs_busy needs to release its 434 * reference on the mount point in this case and return with ENOENT, 435 * telling the caller that mount mount it tried to busy is no longer 436 * valid. 437 */ 438 while (mp->mnt_kern_flag & MNTK_UNMOUNT) { 439 if (flags & MBF_NOWAIT || mp->mnt_kern_flag & MNTK_REFEXPIRE) { 440 MNT_REL(mp); 441 MNT_IUNLOCK(mp); 442 CTR1(KTR_VFS, "%s: failed busying before sleeping", 443 __func__); 444 return (ENOENT); 445 } 446 if (flags & MBF_MNTLSTLOCK) 447 mtx_unlock(&mountlist_mtx); 448 mp->mnt_kern_flag |= MNTK_MWAIT; 449 msleep(mp, MNT_MTX(mp), PVFS | PDROP, "vfs_busy", 0); 450 if (flags & MBF_MNTLSTLOCK) 451 mtx_lock(&mountlist_mtx); 452 MNT_ILOCK(mp); 453 } 454 if (flags & MBF_MNTLSTLOCK) 455 mtx_unlock(&mountlist_mtx); 456 mp->mnt_lockref++; 457 MNT_IUNLOCK(mp); 458 return (0); 459} 460 461/* 462 * Free a busy filesystem. 463 */ 464void 465vfs_unbusy(struct mount *mp) 466{ 467 468 CTR2(KTR_VFS, "%s: mp %p", __func__, mp); 469 MNT_ILOCK(mp); 470 MNT_REL(mp); 471 KASSERT(mp->mnt_lockref > 0, ("negative mnt_lockref")); 472 mp->mnt_lockref--; 473 if (mp->mnt_lockref == 0 && (mp->mnt_kern_flag & MNTK_DRAINING) != 0) { 474 MPASS(mp->mnt_kern_flag & MNTK_UNMOUNT); 475 CTR1(KTR_VFS, "%s: waking up waiters", __func__); 476 mp->mnt_kern_flag &= ~MNTK_DRAINING; 477 wakeup(&mp->mnt_lockref); 478 } 479 MNT_IUNLOCK(mp); 480} 481 482/* 483 * Lookup a mount point by filesystem identifier. 484 */ 485struct mount * 486vfs_getvfs(fsid_t *fsid) 487{ 488 struct mount *mp; 489 490 CTR2(KTR_VFS, "%s: fsid %p", __func__, fsid); 491 mtx_lock(&mountlist_mtx); 492 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 493 if (mp->mnt_stat.f_fsid.val[0] == fsid->val[0] && 494 mp->mnt_stat.f_fsid.val[1] == fsid->val[1]) { 495 vfs_ref(mp); 496 mtx_unlock(&mountlist_mtx); 497 return (mp); 498 } 499 } 500 mtx_unlock(&mountlist_mtx); 501 CTR2(KTR_VFS, "%s: lookup failed for %p id", __func__, fsid); 502 return ((struct mount *) 0); 503} 504 505/* 506 * Lookup a mount point by filesystem identifier, busying it before 507 * returning. 508 * 509 * To avoid congestion on mountlist_mtx, implement simple direct-mapped 510 * cache for popular filesystem identifiers. The cache is lockess, using 511 * the fact that struct mount's are never freed. In worst case we may 512 * get pointer to unmounted or even different filesystem, so we have to 513 * check what we got, and go slow way if so. 514 */ 515struct mount * 516vfs_busyfs(fsid_t *fsid) 517{ 518#define FSID_CACHE_SIZE 256 519 typedef struct mount * volatile vmp_t; 520 static vmp_t cache[FSID_CACHE_SIZE]; 521 struct mount *mp; 522 int error; 523 uint32_t hash; 524 525 CTR2(KTR_VFS, "%s: fsid %p", __func__, fsid); 526 hash = fsid->val[0] ^ fsid->val[1]; 527 hash = (hash >> 16 ^ hash) & (FSID_CACHE_SIZE - 1); 528 mp = cache[hash]; 529 if (mp == NULL || 530 mp->mnt_stat.f_fsid.val[0] != fsid->val[0] || 531 mp->mnt_stat.f_fsid.val[1] != fsid->val[1]) 532 goto slow; 533 if (vfs_busy(mp, 0) != 0) { 534 cache[hash] = NULL; 535 goto slow; 536 } 537 if (mp->mnt_stat.f_fsid.val[0] == fsid->val[0] && 538 mp->mnt_stat.f_fsid.val[1] == fsid->val[1]) 539 return (mp); 540 else 541 vfs_unbusy(mp); 542 543slow: 544 mtx_lock(&mountlist_mtx); 545 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 546 if (mp->mnt_stat.f_fsid.val[0] == fsid->val[0] && 547 mp->mnt_stat.f_fsid.val[1] == fsid->val[1]) { 548 error = vfs_busy(mp, MBF_MNTLSTLOCK); 549 if (error) { 550 cache[hash] = NULL; 551 mtx_unlock(&mountlist_mtx); 552 return (NULL); 553 } 554 cache[hash] = mp; 555 return (mp); 556 } 557 } 558 CTR2(KTR_VFS, "%s: lookup failed for %p id", __func__, fsid); 559 mtx_unlock(&mountlist_mtx); 560 return ((struct mount *) 0); 561} 562 563/* 564 * Check if a user can access privileged mount options. 565 */ 566int 567vfs_suser(struct mount *mp, struct thread *td) 568{ 569 int error; 570 571 /* 572 * If the thread is jailed, but this is not a jail-friendly file 573 * system, deny immediately. 574 */ 575 if (!(mp->mnt_vfc->vfc_flags & VFCF_JAIL) && jailed(td->td_ucred)) 576 return (EPERM); 577 578 /* 579 * If the file system was mounted outside the jail of the calling 580 * thread, deny immediately. 581 */ 582 if (prison_check(td->td_ucred, mp->mnt_cred) != 0) 583 return (EPERM); 584 585 /* 586 * If file system supports delegated administration, we don't check 587 * for the PRIV_VFS_MOUNT_OWNER privilege - it will be better verified 588 * by the file system itself. 589 * If this is not the user that did original mount, we check for 590 * the PRIV_VFS_MOUNT_OWNER privilege. 591 */ 592 if (!(mp->mnt_vfc->vfc_flags & VFCF_DELEGADMIN) && 593 mp->mnt_cred->cr_uid != td->td_ucred->cr_uid) { 594 if ((error = priv_check(td, PRIV_VFS_MOUNT_OWNER)) != 0) 595 return (error); 596 } 597 return (0); 598} 599 600/* 601 * Get a new unique fsid. Try to make its val[0] unique, since this value 602 * will be used to create fake device numbers for stat(). Also try (but 603 * not so hard) make its val[0] unique mod 2^16, since some emulators only 604 * support 16-bit device numbers. We end up with unique val[0]'s for the 605 * first 2^16 calls and unique val[0]'s mod 2^16 for the first 2^8 calls. 606 * 607 * Keep in mind that several mounts may be running in parallel. Starting 608 * the search one past where the previous search terminated is both a 609 * micro-optimization and a defense against returning the same fsid to 610 * different mounts. 611 */ 612void 613vfs_getnewfsid(struct mount *mp) 614{ 615 static uint16_t mntid_base; 616 struct mount *nmp; 617 fsid_t tfsid; 618 int mtype; 619 620 CTR2(KTR_VFS, "%s: mp %p", __func__, mp); 621 mtx_lock(&mntid_mtx); 622 mtype = mp->mnt_vfc->vfc_typenum; 623 tfsid.val[1] = mtype; 624 mtype = (mtype & 0xFF) << 24; 625 for (;;) { 626 tfsid.val[0] = makedev(255, 627 mtype | ((mntid_base & 0xFF00) << 8) | (mntid_base & 0xFF)); 628 mntid_base++; 629 if ((nmp = vfs_getvfs(&tfsid)) == NULL) 630 break; 631 vfs_rel(nmp); 632 } 633 mp->mnt_stat.f_fsid.val[0] = tfsid.val[0]; 634 mp->mnt_stat.f_fsid.val[1] = tfsid.val[1]; 635 mtx_unlock(&mntid_mtx); 636} 637 638/* 639 * Knob to control the precision of file timestamps: 640 * 641 * 0 = seconds only; nanoseconds zeroed. 642 * 1 = seconds and nanoseconds, accurate within 1/HZ. 643 * 2 = seconds and nanoseconds, truncated to microseconds. 644 * >=3 = seconds and nanoseconds, maximum precision. 645 */ 646enum { TSP_SEC, TSP_HZ, TSP_USEC, TSP_NSEC }; 647 648static int timestamp_precision = TSP_USEC; 649SYSCTL_INT(_vfs, OID_AUTO, timestamp_precision, CTLFLAG_RW, 650 ×tamp_precision, 0, "File timestamp precision (0: seconds, " 651 "1: sec + ns accurate to 1/HZ, 2: sec + ns truncated to ms, " 652 "3+: sec + ns (max. precision))"); 653 654/* 655 * Get a current timestamp. 656 */ 657void 658vfs_timestamp(struct timespec *tsp) 659{ 660 struct timeval tv; 661 662 switch (timestamp_precision) { 663 case TSP_SEC: 664 tsp->tv_sec = time_second; 665 tsp->tv_nsec = 0; 666 break; 667 case TSP_HZ: 668 getnanotime(tsp); 669 break; 670 case TSP_USEC: 671 microtime(&tv); 672 TIMEVAL_TO_TIMESPEC(&tv, tsp); 673 break; 674 case TSP_NSEC: 675 default: 676 nanotime(tsp); 677 break; 678 } 679} 680 681/* 682 * Set vnode attributes to VNOVAL 683 */ 684void 685vattr_null(struct vattr *vap) 686{ 687 688 vap->va_type = VNON; 689 vap->va_size = VNOVAL; 690 vap->va_bytes = VNOVAL; 691 vap->va_mode = VNOVAL; 692 vap->va_nlink = VNOVAL; 693 vap->va_uid = VNOVAL; 694 vap->va_gid = VNOVAL; 695 vap->va_fsid = VNOVAL; 696 vap->va_fileid = VNOVAL; 697 vap->va_blocksize = VNOVAL; 698 vap->va_rdev = VNOVAL; 699 vap->va_atime.tv_sec = VNOVAL; 700 vap->va_atime.tv_nsec = VNOVAL; 701 vap->va_mtime.tv_sec = VNOVAL; 702 vap->va_mtime.tv_nsec = VNOVAL; 703 vap->va_ctime.tv_sec = VNOVAL; 704 vap->va_ctime.tv_nsec = VNOVAL; 705 vap->va_birthtime.tv_sec = VNOVAL; 706 vap->va_birthtime.tv_nsec = VNOVAL; 707 vap->va_flags = VNOVAL; 708 vap->va_gen = VNOVAL; 709 vap->va_vaflags = 0; 710} 711 712/* 713 * This routine is called when we have too many vnodes. It attempts 714 * to free <count> vnodes and will potentially free vnodes that still 715 * have VM backing store (VM backing store is typically the cause 716 * of a vnode blowout so we want to do this). Therefore, this operation 717 * is not considered cheap. 718 * 719 * A number of conditions may prevent a vnode from being reclaimed. 720 * the buffer cache may have references on the vnode, a directory 721 * vnode may still have references due to the namei cache representing 722 * underlying files, or the vnode may be in active use. It is not 723 * desireable to reuse such vnodes. These conditions may cause the 724 * number of vnodes to reach some minimum value regardless of what 725 * you set kern.maxvnodes to. Do not set kern.maxvnodes too low. 726 */ 727static int 728vlrureclaim(struct mount *mp) 729{ 730 struct vnode *vp; 731 int done; 732 int trigger; 733 int usevnodes; 734 int count; 735 736 /* 737 * Calculate the trigger point, don't allow user 738 * screwups to blow us up. This prevents us from 739 * recycling vnodes with lots of resident pages. We 740 * aren't trying to free memory, we are trying to 741 * free vnodes. 742 */ 743 usevnodes = desiredvnodes; 744 if (usevnodes <= 0) 745 usevnodes = 1; 746 trigger = cnt.v_page_count * 2 / usevnodes; 747 done = 0; 748 vn_start_write(NULL, &mp, V_WAIT); 749 MNT_ILOCK(mp); 750 count = mp->mnt_nvnodelistsize / 10 + 1; 751 while (count != 0) { 752 vp = TAILQ_FIRST(&mp->mnt_nvnodelist); 753 while (vp != NULL && vp->v_type == VMARKER) 754 vp = TAILQ_NEXT(vp, v_nmntvnodes); 755 if (vp == NULL) 756 break; 757 TAILQ_REMOVE(&mp->mnt_nvnodelist, vp, v_nmntvnodes); 758 TAILQ_INSERT_TAIL(&mp->mnt_nvnodelist, vp, v_nmntvnodes); 759 --count; 760 if (!VI_TRYLOCK(vp)) 761 goto next_iter; 762 /* 763 * If it's been deconstructed already, it's still 764 * referenced, or it exceeds the trigger, skip it. 765 */ 766 if (vp->v_usecount || 767 (!vlru_allow_cache_src && 768 !LIST_EMPTY(&(vp)->v_cache_src)) || 769 (vp->v_iflag & VI_DOOMED) != 0 || (vp->v_object != NULL && 770 vp->v_object->resident_page_count > trigger)) { 771 VI_UNLOCK(vp); 772 goto next_iter; 773 } 774 MNT_IUNLOCK(mp); 775 vholdl(vp); 776 if (VOP_LOCK(vp, LK_INTERLOCK|LK_EXCLUSIVE|LK_NOWAIT)) { 777 vdrop(vp); 778 goto next_iter_mntunlocked; 779 } 780 VI_LOCK(vp); 781 /* 782 * v_usecount may have been bumped after VOP_LOCK() dropped 783 * the vnode interlock and before it was locked again. 784 * 785 * It is not necessary to recheck VI_DOOMED because it can 786 * only be set by another thread that holds both the vnode 787 * lock and vnode interlock. If another thread has the 788 * vnode lock before we get to VOP_LOCK() and obtains the 789 * vnode interlock after VOP_LOCK() drops the vnode 790 * interlock, the other thread will be unable to drop the 791 * vnode lock before our VOP_LOCK() call fails. 792 */ 793 if (vp->v_usecount || 794 (!vlru_allow_cache_src && 795 !LIST_EMPTY(&(vp)->v_cache_src)) || 796 (vp->v_object != NULL && 797 vp->v_object->resident_page_count > trigger)) { 798 VOP_UNLOCK(vp, LK_INTERLOCK); 799 vdrop(vp); 800 goto next_iter_mntunlocked; 801 } 802 KASSERT((vp->v_iflag & VI_DOOMED) == 0, 803 ("VI_DOOMED unexpectedly detected in vlrureclaim()")); 804 atomic_add_long(&recycles_count, 1); 805 vgonel(vp); 806 VOP_UNLOCK(vp, 0); 807 vdropl(vp); 808 done++; 809next_iter_mntunlocked: 810 if (!should_yield()) 811 goto relock_mnt; 812 goto yield; 813next_iter: 814 if (!should_yield()) 815 continue; 816 MNT_IUNLOCK(mp); 817yield: 818 kern_yield(PRI_USER); 819relock_mnt: 820 MNT_ILOCK(mp); 821 } 822 MNT_IUNLOCK(mp); 823 vn_finished_write(mp); 824 return done; 825} 826 827/* 828 * Attempt to keep the free list at wantfreevnodes length. 829 */ 830static void 831vnlru_free(int count) 832{ 833 struct vnode *vp; 834 835 mtx_assert(&vnode_free_list_mtx, MA_OWNED); 836 for (; count > 0; count--) { 837 vp = TAILQ_FIRST(&vnode_free_list); 838 /* 839 * The list can be modified while the free_list_mtx 840 * has been dropped and vp could be NULL here. 841 */ 842 if (!vp) 843 break; 844 VNASSERT(vp->v_op != NULL, vp, 845 ("vnlru_free: vnode already reclaimed.")); 846 KASSERT((vp->v_iflag & VI_FREE) != 0, 847 ("Removing vnode not on freelist")); 848 KASSERT((vp->v_iflag & VI_ACTIVE) == 0, 849 ("Mangling active vnode")); 850 TAILQ_REMOVE(&vnode_free_list, vp, v_actfreelist); 851 /* 852 * Don't recycle if we can't get the interlock. 853 */ 854 if (!VI_TRYLOCK(vp)) { 855 TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_actfreelist); 856 continue; 857 } 858 VNASSERT((vp->v_iflag & VI_FREE) != 0 && vp->v_holdcnt == 0, 859 vp, ("vp inconsistent on freelist")); 860 861 /* 862 * The clear of VI_FREE prevents activation of the 863 * vnode. There is no sense in putting the vnode on 864 * the mount point active list, only to remove it 865 * later during recycling. Inline the relevant part 866 * of vholdl(), to avoid triggering assertions or 867 * activating. 868 */ 869 freevnodes--; 870 vp->v_iflag &= ~VI_FREE; 871 vp->v_holdcnt++; 872 873 mtx_unlock(&vnode_free_list_mtx); 874 VI_UNLOCK(vp); 875 vtryrecycle(vp); 876 /* 877 * If the recycled succeeded this vdrop will actually free 878 * the vnode. If not it will simply place it back on 879 * the free list. 880 */ 881 vdrop(vp); 882 mtx_lock(&vnode_free_list_mtx); 883 } 884} 885/* 886 * Attempt to recycle vnodes in a context that is always safe to block. 887 * Calling vlrurecycle() from the bowels of filesystem code has some 888 * interesting deadlock problems. 889 */ 890static struct proc *vnlruproc; 891static int vnlruproc_sig; 892 893static void 894vnlru_proc(void) 895{ 896 struct mount *mp, *nmp; 897 int done; 898 struct proc *p = vnlruproc; 899 900 EVENTHANDLER_REGISTER(shutdown_pre_sync, kproc_shutdown, p, 901 SHUTDOWN_PRI_FIRST); 902 903 for (;;) { 904 kproc_suspend_check(p); 905 mtx_lock(&vnode_free_list_mtx); 906 if (freevnodes > wantfreevnodes) 907 vnlru_free(freevnodes - wantfreevnodes); 908 if (numvnodes <= desiredvnodes * 9 / 10) { 909 vnlruproc_sig = 0; 910 wakeup(&vnlruproc_sig); 911 msleep(vnlruproc, &vnode_free_list_mtx, 912 PVFS|PDROP, "vlruwt", hz); 913 continue; 914 } 915 mtx_unlock(&vnode_free_list_mtx); 916 done = 0; 917 mtx_lock(&mountlist_mtx); 918 for (mp = TAILQ_FIRST(&mountlist); mp != NULL; mp = nmp) { 919 if (vfs_busy(mp, MBF_NOWAIT | MBF_MNTLSTLOCK)) { 920 nmp = TAILQ_NEXT(mp, mnt_list); 921 continue; 922 } 923 done += vlrureclaim(mp); 924 mtx_lock(&mountlist_mtx); 925 nmp = TAILQ_NEXT(mp, mnt_list); 926 vfs_unbusy(mp); 927 } 928 mtx_unlock(&mountlist_mtx); 929 if (done == 0) { 930#if 0 931 /* These messages are temporary debugging aids */ 932 if (vnlru_nowhere < 5) 933 printf("vnlru process getting nowhere..\n"); 934 else if (vnlru_nowhere == 5) 935 printf("vnlru process messages stopped.\n"); 936#endif 937 vnlru_nowhere++; 938 tsleep(vnlruproc, PPAUSE, "vlrup", hz * 3); 939 } else 940 kern_yield(PRI_USER); 941 } 942} 943 944static struct kproc_desc vnlru_kp = { 945 "vnlru", 946 vnlru_proc, 947 &vnlruproc 948}; 949SYSINIT(vnlru, SI_SUB_KTHREAD_UPDATE, SI_ORDER_FIRST, kproc_start, 950 &vnlru_kp); 951 952/* 953 * Routines having to do with the management of the vnode table. 954 */ 955 956/* 957 * Try to recycle a freed vnode. We abort if anyone picks up a reference 958 * before we actually vgone(). This function must be called with the vnode 959 * held to prevent the vnode from being returned to the free list midway 960 * through vgone(). 961 */ 962static int 963vtryrecycle(struct vnode *vp) 964{ 965 struct mount *vnmp; 966 967 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 968 VNASSERT(vp->v_holdcnt, vp, 969 ("vtryrecycle: Recycling vp %p without a reference.", vp)); 970 /* 971 * This vnode may found and locked via some other list, if so we 972 * can't recycle it yet. 973 */ 974 if (VOP_LOCK(vp, LK_EXCLUSIVE | LK_NOWAIT) != 0) { 975 CTR2(KTR_VFS, 976 "%s: impossible to recycle, vp %p lock is already held", 977 __func__, vp); 978 return (EWOULDBLOCK); 979 } 980 /* 981 * Don't recycle if its filesystem is being suspended. 982 */ 983 if (vn_start_write(vp, &vnmp, V_NOWAIT) != 0) { 984 VOP_UNLOCK(vp, 0); 985 CTR2(KTR_VFS, 986 "%s: impossible to recycle, cannot start the write for %p", 987 __func__, vp); 988 return (EBUSY); 989 } 990 /* 991 * If we got this far, we need to acquire the interlock and see if 992 * anyone picked up this vnode from another list. If not, we will 993 * mark it with DOOMED via vgonel() so that anyone who does find it 994 * will skip over it. 995 */ 996 VI_LOCK(vp); 997 if (vp->v_usecount) { 998 VOP_UNLOCK(vp, LK_INTERLOCK); 999 vn_finished_write(vnmp); 1000 CTR2(KTR_VFS, 1001 "%s: impossible to recycle, %p is already referenced", 1002 __func__, vp); 1003 return (EBUSY); 1004 } 1005 if ((vp->v_iflag & VI_DOOMED) == 0) { 1006 atomic_add_long(&recycles_count, 1); 1007 vgonel(vp); 1008 } 1009 VOP_UNLOCK(vp, LK_INTERLOCK); 1010 vn_finished_write(vnmp); 1011 return (0); 1012} 1013 1014/* 1015 * Wait for available vnodes. 1016 */ 1017static int 1018getnewvnode_wait(int suspended) 1019{ 1020 1021 mtx_assert(&vnode_free_list_mtx, MA_OWNED); 1022 if (numvnodes > desiredvnodes) { 1023 if (suspended) { 1024 /* 1025 * File system is beeing suspended, we cannot risk a 1026 * deadlock here, so allocate new vnode anyway. 1027 */ 1028 if (freevnodes > wantfreevnodes) 1029 vnlru_free(freevnodes - wantfreevnodes); 1030 return (0); 1031 } 1032 if (vnlruproc_sig == 0) { 1033 vnlruproc_sig = 1; /* avoid unnecessary wakeups */ 1034 wakeup(vnlruproc); 1035 } 1036 msleep(&vnlruproc_sig, &vnode_free_list_mtx, PVFS, 1037 "vlruwk", hz); 1038 } 1039 return (numvnodes > desiredvnodes ? ENFILE : 0); 1040} 1041 1042void 1043getnewvnode_reserve(u_int count) 1044{ 1045 struct thread *td; 1046 1047 td = curthread; 1048 /* First try to be quick and racy. */ 1049 if (atomic_fetchadd_long(&numvnodes, count) + count <= desiredvnodes) { 1050 td->td_vp_reserv += count; 1051 return; 1052 } else 1053 atomic_subtract_long(&numvnodes, count); 1054 1055 mtx_lock(&vnode_free_list_mtx); 1056 while (count > 0) { 1057 if (getnewvnode_wait(0) == 0) { 1058 count--; 1059 td->td_vp_reserv++; 1060 atomic_add_long(&numvnodes, 1); 1061 } 1062 } 1063 mtx_unlock(&vnode_free_list_mtx); 1064} 1065 1066void 1067getnewvnode_drop_reserve(void) 1068{ 1069 struct thread *td; 1070 1071 td = curthread; 1072 atomic_subtract_long(&numvnodes, td->td_vp_reserv); 1073 td->td_vp_reserv = 0; 1074} 1075 1076/* 1077 * Return the next vnode from the free list. 1078 */ 1079int 1080getnewvnode(const char *tag, struct mount *mp, struct vop_vector *vops, 1081 struct vnode **vpp) 1082{ 1083 struct vnode *vp; 1084 struct bufobj *bo; 1085 struct thread *td; 1086 int error; 1087 1088 CTR3(KTR_VFS, "%s: mp %p with tag %s", __func__, mp, tag); 1089 vp = NULL; 1090 td = curthread; 1091 if (td->td_vp_reserv > 0) { 1092 td->td_vp_reserv -= 1; 1093 goto alloc; 1094 } 1095 mtx_lock(&vnode_free_list_mtx); 1096 /* 1097 * Lend our context to reclaim vnodes if they've exceeded the max. 1098 */ 1099 if (freevnodes > wantfreevnodes) 1100 vnlru_free(1); 1101 error = getnewvnode_wait(mp != NULL && (mp->mnt_kern_flag & 1102 MNTK_SUSPEND)); 1103#if 0 /* XXX Not all VFS_VGET/ffs_vget callers check returns. */ 1104 if (error != 0) { 1105 mtx_unlock(&vnode_free_list_mtx); 1106 return (error); 1107 } 1108#endif 1109 atomic_add_long(&numvnodes, 1); 1110 mtx_unlock(&vnode_free_list_mtx); 1111alloc: 1112 atomic_add_long(&vnodes_created, 1); 1113 vp = (struct vnode *) uma_zalloc(vnode_zone, M_WAITOK|M_ZERO); 1114 /* 1115 * Setup locks. 1116 */ 1117 vp->v_vnlock = &vp->v_lock; 1118 mtx_init(&vp->v_interlock, "vnode interlock", NULL, MTX_DEF); 1119 /* 1120 * By default, don't allow shared locks unless filesystems 1121 * opt-in. 1122 */ 1123 lockinit(vp->v_vnlock, PVFS, tag, VLKTIMEOUT, LK_NOSHARE | LK_IS_VNODE); 1124 /* 1125 * Initialize bufobj. 1126 */ 1127 bo = &vp->v_bufobj; 1128 bo->__bo_vnode = vp; 1129 rw_init(BO_LOCKPTR(bo), "bufobj interlock"); 1130 bo->bo_ops = &buf_ops_bio; 1131 bo->bo_private = vp; 1132 TAILQ_INIT(&bo->bo_clean.bv_hd); 1133 TAILQ_INIT(&bo->bo_dirty.bv_hd); 1134 /* 1135 * Initialize namecache. 1136 */ 1137 LIST_INIT(&vp->v_cache_src); 1138 TAILQ_INIT(&vp->v_cache_dst); 1139 /* 1140 * Finalize various vnode identity bits. 1141 */ 1142 vp->v_type = VNON; 1143 vp->v_tag = tag; 1144 vp->v_op = vops; 1145 v_incr_usecount(vp); 1146 vp->v_data = NULL; 1147#ifdef MAC 1148 mac_vnode_init(vp); 1149 if (mp != NULL && (mp->mnt_flag & MNT_MULTILABEL) == 0) 1150 mac_vnode_associate_singlelabel(mp, vp); 1151 else if (mp == NULL && vops != &dead_vnodeops) 1152 printf("NULL mp in getnewvnode()\n"); 1153#endif 1154 if (mp != NULL) { 1155 bo->bo_bsize = mp->mnt_stat.f_iosize; 1156 if ((mp->mnt_kern_flag & MNTK_NOKNOTE) != 0) 1157 vp->v_vflag |= VV_NOKNOTE; 1158 } 1159 rangelock_init(&vp->v_rl); 1160 1161 /* 1162 * For the filesystems which do not use vfs_hash_insert(), 1163 * still initialize v_hash to have vfs_hash_index() useful. 1164 * E.g., nullfs uses vfs_hash_index() on the lower vnode for 1165 * its own hashing. 1166 */ 1167 vp->v_hash = (uintptr_t)vp >> vnsz2log; 1168 1169 *vpp = vp; 1170 return (0); 1171} 1172 1173/* 1174 * Delete from old mount point vnode list, if on one. 1175 */ 1176static void 1177delmntque(struct vnode *vp) 1178{ 1179 struct mount *mp; 1180 int active; 1181 1182 mp = vp->v_mount; 1183 if (mp == NULL) 1184 return; 1185 MNT_ILOCK(mp); 1186 VI_LOCK(vp); 1187 KASSERT(mp->mnt_activevnodelistsize <= mp->mnt_nvnodelistsize, 1188 ("Active vnode list size %d > Vnode list size %d", 1189 mp->mnt_activevnodelistsize, mp->mnt_nvnodelistsize)); 1190 active = vp->v_iflag & VI_ACTIVE; 1191 vp->v_iflag &= ~VI_ACTIVE; 1192 if (active) { 1193 mtx_lock(&vnode_free_list_mtx); 1194 TAILQ_REMOVE(&mp->mnt_activevnodelist, vp, v_actfreelist); 1195 mp->mnt_activevnodelistsize--; 1196 mtx_unlock(&vnode_free_list_mtx); 1197 } 1198 vp->v_mount = NULL; 1199 VI_UNLOCK(vp); 1200 VNASSERT(mp->mnt_nvnodelistsize > 0, vp, 1201 ("bad mount point vnode list size")); 1202 TAILQ_REMOVE(&mp->mnt_nvnodelist, vp, v_nmntvnodes); 1203 mp->mnt_nvnodelistsize--; 1204 MNT_REL(mp); 1205 MNT_IUNLOCK(mp); 1206} 1207 1208static void 1209insmntque_stddtr(struct vnode *vp, void *dtr_arg) 1210{ 1211 1212 vp->v_data = NULL; 1213 vp->v_op = &dead_vnodeops; 1214 vgone(vp); 1215 vput(vp); 1216} 1217 1218/* 1219 * Insert into list of vnodes for the new mount point, if available. 1220 */ 1221int 1222insmntque1(struct vnode *vp, struct mount *mp, 1223 void (*dtr)(struct vnode *, void *), void *dtr_arg) 1224{ 1225 1226 KASSERT(vp->v_mount == NULL, 1227 ("insmntque: vnode already on per mount vnode list")); 1228 VNASSERT(mp != NULL, vp, ("Don't call insmntque(foo, NULL)")); 1229 ASSERT_VOP_ELOCKED(vp, "insmntque: non-locked vp"); 1230 1231 /* 1232 * We acquire the vnode interlock early to ensure that the 1233 * vnode cannot be recycled by another process releasing a 1234 * holdcnt on it before we get it on both the vnode list 1235 * and the active vnode list. The mount mutex protects only 1236 * manipulation of the vnode list and the vnode freelist 1237 * mutex protects only manipulation of the active vnode list. 1238 * Hence the need to hold the vnode interlock throughout. 1239 */ 1240 MNT_ILOCK(mp); 1241 VI_LOCK(vp); 1242 if (((mp->mnt_kern_flag & MNTK_NOINSMNTQ) != 0 && 1243 ((mp->mnt_kern_flag & MNTK_UNMOUNTF) != 0 || 1244 mp->mnt_nvnodelistsize == 0)) && 1245 (vp->v_vflag & VV_FORCEINSMQ) == 0) { 1246 VI_UNLOCK(vp); 1247 MNT_IUNLOCK(mp); 1248 if (dtr != NULL) 1249 dtr(vp, dtr_arg); 1250 return (EBUSY); 1251 } 1252 vp->v_mount = mp; 1253 MNT_REF(mp); 1254 TAILQ_INSERT_TAIL(&mp->mnt_nvnodelist, vp, v_nmntvnodes); 1255 VNASSERT(mp->mnt_nvnodelistsize >= 0, vp, 1256 ("neg mount point vnode list size")); 1257 mp->mnt_nvnodelistsize++; 1258 KASSERT((vp->v_iflag & VI_ACTIVE) == 0, 1259 ("Activating already active vnode")); 1260 vp->v_iflag |= VI_ACTIVE; 1261 mtx_lock(&vnode_free_list_mtx); 1262 TAILQ_INSERT_HEAD(&mp->mnt_activevnodelist, vp, v_actfreelist); 1263 mp->mnt_activevnodelistsize++; 1264 mtx_unlock(&vnode_free_list_mtx); 1265 VI_UNLOCK(vp); 1266 MNT_IUNLOCK(mp); 1267 return (0); 1268} 1269 1270int 1271insmntque(struct vnode *vp, struct mount *mp) 1272{ 1273 1274 return (insmntque1(vp, mp, insmntque_stddtr, NULL)); 1275} 1276 1277/* 1278 * Flush out and invalidate all buffers associated with a bufobj 1279 * Called with the underlying object locked. 1280 */ 1281int 1282bufobj_invalbuf(struct bufobj *bo, int flags, int slpflag, int slptimeo) 1283{ 1284 int error; 1285 1286 BO_LOCK(bo); 1287 if (flags & V_SAVE) { 1288 error = bufobj_wwait(bo, slpflag, slptimeo); 1289 if (error) { 1290 BO_UNLOCK(bo); 1291 return (error); 1292 } 1293 if (bo->bo_dirty.bv_cnt > 0) { 1294 BO_UNLOCK(bo); 1295 if ((error = BO_SYNC(bo, MNT_WAIT)) != 0) 1296 return (error); 1297 /* 1298 * XXX We could save a lock/unlock if this was only 1299 * enabled under INVARIANTS 1300 */ 1301 BO_LOCK(bo); 1302 if (bo->bo_numoutput > 0 || bo->bo_dirty.bv_cnt > 0) 1303 panic("vinvalbuf: dirty bufs"); 1304 } 1305 } 1306 /* 1307 * If you alter this loop please notice that interlock is dropped and 1308 * reacquired in flushbuflist. Special care is needed to ensure that 1309 * no race conditions occur from this. 1310 */ 1311 do { 1312 error = flushbuflist(&bo->bo_clean, 1313 flags, bo, slpflag, slptimeo); 1314 if (error == 0 && !(flags & V_CLEANONLY)) 1315 error = flushbuflist(&bo->bo_dirty, 1316 flags, bo, slpflag, slptimeo); 1317 if (error != 0 && error != EAGAIN) { 1318 BO_UNLOCK(bo); 1319 return (error); 1320 } 1321 } while (error != 0); 1322 1323 /* 1324 * Wait for I/O to complete. XXX needs cleaning up. The vnode can 1325 * have write I/O in-progress but if there is a VM object then the 1326 * VM object can also have read-I/O in-progress. 1327 */ 1328 do { 1329 bufobj_wwait(bo, 0, 0); 1330 BO_UNLOCK(bo); 1331 if (bo->bo_object != NULL) { 1332 VM_OBJECT_WLOCK(bo->bo_object); 1333 vm_object_pip_wait(bo->bo_object, "bovlbx"); 1334 VM_OBJECT_WUNLOCK(bo->bo_object); 1335 } 1336 BO_LOCK(bo); 1337 } while (bo->bo_numoutput > 0); 1338 BO_UNLOCK(bo); 1339 1340 /* 1341 * Destroy the copy in the VM cache, too. 1342 */ 1343 if (bo->bo_object != NULL && 1344 (flags & (V_ALT | V_NORMAL | V_CLEANONLY)) == 0) { 1345 VM_OBJECT_WLOCK(bo->bo_object); 1346 vm_object_page_remove(bo->bo_object, 0, 0, (flags & V_SAVE) ? 1347 OBJPR_CLEANONLY : 0); 1348 VM_OBJECT_WUNLOCK(bo->bo_object); 1349 } 1350 1351#ifdef INVARIANTS 1352 BO_LOCK(bo); 1353 if ((flags & (V_ALT | V_NORMAL | V_CLEANONLY)) == 0 && 1354 (bo->bo_dirty.bv_cnt > 0 || bo->bo_clean.bv_cnt > 0)) 1355 panic("vinvalbuf: flush failed"); 1356 BO_UNLOCK(bo); 1357#endif 1358 return (0); 1359} 1360 1361/* 1362 * Flush out and invalidate all buffers associated with a vnode. 1363 * Called with the underlying object locked. 1364 */ 1365int 1366vinvalbuf(struct vnode *vp, int flags, int slpflag, int slptimeo) 1367{ 1368 1369 CTR3(KTR_VFS, "%s: vp %p with flags %d", __func__, vp, flags); 1370 ASSERT_VOP_LOCKED(vp, "vinvalbuf"); 1371 if (vp->v_object != NULL && vp->v_object->handle != vp) 1372 return (0); 1373 return (bufobj_invalbuf(&vp->v_bufobj, flags, slpflag, slptimeo)); 1374} 1375 1376/* 1377 * Flush out buffers on the specified list. 1378 * 1379 */ 1380static int 1381flushbuflist(struct bufv *bufv, int flags, struct bufobj *bo, int slpflag, 1382 int slptimeo) 1383{ 1384 struct buf *bp, *nbp; 1385 int retval, error; 1386 daddr_t lblkno; 1387 b_xflags_t xflags; 1388 1389 ASSERT_BO_WLOCKED(bo); 1390 1391 retval = 0; 1392 TAILQ_FOREACH_SAFE(bp, &bufv->bv_hd, b_bobufs, nbp) { 1393 if (((flags & V_NORMAL) && (bp->b_xflags & BX_ALTDATA)) || 1394 ((flags & V_ALT) && (bp->b_xflags & BX_ALTDATA) == 0)) { 1395 continue; 1396 } 1397 lblkno = 0; 1398 xflags = 0; 1399 if (nbp != NULL) { 1400 lblkno = nbp->b_lblkno; 1401 xflags = nbp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN); 1402 } 1403 retval = EAGAIN; 1404 error = BUF_TIMELOCK(bp, 1405 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, BO_LOCKPTR(bo), 1406 "flushbuf", slpflag, slptimeo); 1407 if (error) { 1408 BO_LOCK(bo); 1409 return (error != ENOLCK ? error : EAGAIN); 1410 } 1411 KASSERT(bp->b_bufobj == bo, 1412 ("bp %p wrong b_bufobj %p should be %p", 1413 bp, bp->b_bufobj, bo)); 1414 if (bp->b_bufobj != bo) { /* XXX: necessary ? */ 1415 BUF_UNLOCK(bp); 1416 BO_LOCK(bo); 1417 return (EAGAIN); 1418 } 1419 /* 1420 * XXX Since there are no node locks for NFS, I 1421 * believe there is a slight chance that a delayed 1422 * write will occur while sleeping just above, so 1423 * check for it. 1424 */ 1425 if (((bp->b_flags & (B_DELWRI | B_INVAL)) == B_DELWRI) && 1426 (flags & V_SAVE)) { 1427 bremfree(bp); 1428 bp->b_flags |= B_ASYNC; 1429 bwrite(bp); 1430 BO_LOCK(bo); 1431 return (EAGAIN); /* XXX: why not loop ? */ 1432 } 1433 bremfree(bp); 1434 bp->b_flags |= (B_INVAL | B_RELBUF); 1435 bp->b_flags &= ~B_ASYNC; 1436 brelse(bp); 1437 BO_LOCK(bo); 1438 if (nbp != NULL && 1439 (nbp->b_bufobj != bo || 1440 nbp->b_lblkno != lblkno || 1441 (nbp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN)) != xflags)) 1442 break; /* nbp invalid */ 1443 } 1444 return (retval); 1445} 1446 1447/* 1448 * Truncate a file's buffer and pages to a specified length. This 1449 * is in lieu of the old vinvalbuf mechanism, which performed unneeded 1450 * sync activity. 1451 */ 1452int 1453vtruncbuf(struct vnode *vp, struct ucred *cred, off_t length, int blksize) 1454{ 1455 struct buf *bp, *nbp; 1456 int anyfreed; 1457 int trunclbn; 1458 struct bufobj *bo; 1459 1460 CTR5(KTR_VFS, "%s: vp %p with cred %p and block %d:%ju", __func__, 1461 vp, cred, blksize, (uintmax_t)length); 1462 1463 /* 1464 * Round up to the *next* lbn. 1465 */ 1466 trunclbn = (length + blksize - 1) / blksize; 1467 1468 ASSERT_VOP_LOCKED(vp, "vtruncbuf"); 1469restart: 1470 bo = &vp->v_bufobj; 1471 BO_LOCK(bo); 1472 anyfreed = 1; 1473 for (;anyfreed;) { 1474 anyfreed = 0; 1475 TAILQ_FOREACH_SAFE(bp, &bo->bo_clean.bv_hd, b_bobufs, nbp) { 1476 if (bp->b_lblkno < trunclbn) 1477 continue; 1478 if (BUF_LOCK(bp, 1479 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, 1480 BO_LOCKPTR(bo)) == ENOLCK) 1481 goto restart; 1482 1483 bremfree(bp); 1484 bp->b_flags |= (B_INVAL | B_RELBUF); 1485 bp->b_flags &= ~B_ASYNC; 1486 brelse(bp); 1487 anyfreed = 1; 1488 1489 BO_LOCK(bo); 1490 if (nbp != NULL && 1491 (((nbp->b_xflags & BX_VNCLEAN) == 0) || 1492 (nbp->b_vp != vp) || 1493 (nbp->b_flags & B_DELWRI))) { 1494 BO_UNLOCK(bo); 1495 goto restart; 1496 } 1497 } 1498 1499 TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) { 1500 if (bp->b_lblkno < trunclbn) 1501 continue; 1502 if (BUF_LOCK(bp, 1503 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, 1504 BO_LOCKPTR(bo)) == ENOLCK) 1505 goto restart; 1506 bremfree(bp); 1507 bp->b_flags |= (B_INVAL | B_RELBUF); 1508 bp->b_flags &= ~B_ASYNC; 1509 brelse(bp); 1510 anyfreed = 1; 1511 1512 BO_LOCK(bo); 1513 if (nbp != NULL && 1514 (((nbp->b_xflags & BX_VNDIRTY) == 0) || 1515 (nbp->b_vp != vp) || 1516 (nbp->b_flags & B_DELWRI) == 0)) { 1517 BO_UNLOCK(bo); 1518 goto restart; 1519 } 1520 } 1521 } 1522 1523 if (length > 0) { 1524restartsync: 1525 TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) { 1526 if (bp->b_lblkno > 0) 1527 continue; 1528 /* 1529 * Since we hold the vnode lock this should only 1530 * fail if we're racing with the buf daemon. 1531 */ 1532 if (BUF_LOCK(bp, 1533 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, 1534 BO_LOCKPTR(bo)) == ENOLCK) { 1535 goto restart; 1536 } 1537 VNASSERT((bp->b_flags & B_DELWRI), vp, 1538 ("buf(%p) on dirty queue without DELWRI", bp)); 1539 1540 bremfree(bp); 1541 bawrite(bp); 1542 BO_LOCK(bo); 1543 goto restartsync; 1544 } 1545 } 1546 1547 bufobj_wwait(bo, 0, 0); 1548 BO_UNLOCK(bo); 1549 vnode_pager_setsize(vp, length); 1550 1551 return (0); 1552} 1553 1554static void 1555buf_vlist_remove(struct buf *bp) 1556{ 1557 struct bufv *bv; 1558 1559 KASSERT(bp->b_bufobj != NULL, ("No b_bufobj %p", bp)); 1560 ASSERT_BO_WLOCKED(bp->b_bufobj); 1561 KASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) != 1562 (BX_VNDIRTY|BX_VNCLEAN), 1563 ("buf_vlist_remove: Buf %p is on two lists", bp)); 1564 if (bp->b_xflags & BX_VNDIRTY) 1565 bv = &bp->b_bufobj->bo_dirty; 1566 else 1567 bv = &bp->b_bufobj->bo_clean; 1568 BUF_PCTRIE_REMOVE(&bv->bv_root, bp->b_lblkno); 1569 TAILQ_REMOVE(&bv->bv_hd, bp, b_bobufs); 1570 bv->bv_cnt--; 1571 bp->b_xflags &= ~(BX_VNDIRTY | BX_VNCLEAN); 1572} 1573 1574/* 1575 * Add the buffer to the sorted clean or dirty block list. 1576 * 1577 * NOTE: xflags is passed as a constant, optimizing this inline function! 1578 */ 1579static void 1580buf_vlist_add(struct buf *bp, struct bufobj *bo, b_xflags_t xflags) 1581{ 1582 struct bufv *bv; 1583 struct buf *n; 1584 int error; 1585 1586 ASSERT_BO_WLOCKED(bo); 1587 KASSERT((bo->bo_flag & BO_DEAD) == 0, ("dead bo %p", bo)); 1588 KASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) == 0, 1589 ("buf_vlist_add: Buf %p has existing xflags %d", bp, bp->b_xflags)); 1590 bp->b_xflags |= xflags; 1591 if (xflags & BX_VNDIRTY) 1592 bv = &bo->bo_dirty; 1593 else 1594 bv = &bo->bo_clean; 1595 1596 /* 1597 * Keep the list ordered. Optimize empty list insertion. Assume 1598 * we tend to grow at the tail so lookup_le should usually be cheaper 1599 * than _ge. 1600 */ 1601 if (bv->bv_cnt == 0 || 1602 bp->b_lblkno > TAILQ_LAST(&bv->bv_hd, buflists)->b_lblkno) 1603 TAILQ_INSERT_TAIL(&bv->bv_hd, bp, b_bobufs); 1604 else if ((n = BUF_PCTRIE_LOOKUP_LE(&bv->bv_root, bp->b_lblkno)) == NULL) 1605 TAILQ_INSERT_HEAD(&bv->bv_hd, bp, b_bobufs); 1606 else 1607 TAILQ_INSERT_AFTER(&bv->bv_hd, n, bp, b_bobufs); 1608 error = BUF_PCTRIE_INSERT(&bv->bv_root, bp); 1609 if (error) 1610 panic("buf_vlist_add: Preallocated nodes insufficient."); 1611 bv->bv_cnt++; 1612} 1613 1614/* 1615 * Lookup a buffer using the splay tree. Note that we specifically avoid 1616 * shadow buffers used in background bitmap writes. 1617 * 1618 * This code isn't quite efficient as it could be because we are maintaining 1619 * two sorted lists and do not know which list the block resides in. 1620 * 1621 * During a "make buildworld" the desired buffer is found at one of 1622 * the roots more than 60% of the time. Thus, checking both roots 1623 * before performing either splay eliminates unnecessary splays on the 1624 * first tree splayed. 1625 */ 1626struct buf * 1627gbincore(struct bufobj *bo, daddr_t lblkno) 1628{ 1629 struct buf *bp; 1630 1631 ASSERT_BO_LOCKED(bo); 1632 bp = BUF_PCTRIE_LOOKUP(&bo->bo_clean.bv_root, lblkno); 1633 if (bp != NULL) 1634 return (bp); 1635 return BUF_PCTRIE_LOOKUP(&bo->bo_dirty.bv_root, lblkno); 1636} 1637 1638/* 1639 * Associate a buffer with a vnode. 1640 */ 1641void 1642bgetvp(struct vnode *vp, struct buf *bp) 1643{ 1644 struct bufobj *bo; 1645 1646 bo = &vp->v_bufobj; 1647 ASSERT_BO_WLOCKED(bo); 1648 VNASSERT(bp->b_vp == NULL, bp->b_vp, ("bgetvp: not free")); 1649 1650 CTR3(KTR_BUF, "bgetvp(%p) vp %p flags %X", bp, vp, bp->b_flags); 1651 VNASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) == 0, vp, 1652 ("bgetvp: bp already attached! %p", bp)); 1653 1654 vhold(vp); 1655 bp->b_vp = vp; 1656 bp->b_bufobj = bo; 1657 /* 1658 * Insert onto list for new vnode. 1659 */ 1660 buf_vlist_add(bp, bo, BX_VNCLEAN); 1661} 1662 1663/* 1664 * Disassociate a buffer from a vnode. 1665 */ 1666void 1667brelvp(struct buf *bp) 1668{ 1669 struct bufobj *bo; 1670 struct vnode *vp; 1671 1672 CTR3(KTR_BUF, "brelvp(%p) vp %p flags %X", bp, bp->b_vp, bp->b_flags); 1673 KASSERT(bp->b_vp != NULL, ("brelvp: NULL")); 1674 1675 /* 1676 * Delete from old vnode list, if on one. 1677 */ 1678 vp = bp->b_vp; /* XXX */ 1679 bo = bp->b_bufobj; 1680 BO_LOCK(bo); 1681 if (bp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN)) 1682 buf_vlist_remove(bp); 1683 else 1684 panic("brelvp: Buffer %p not on queue.", bp); 1685 if ((bo->bo_flag & BO_ONWORKLST) && bo->bo_dirty.bv_cnt == 0) { 1686 bo->bo_flag &= ~BO_ONWORKLST; 1687 mtx_lock(&sync_mtx); 1688 LIST_REMOVE(bo, bo_synclist); 1689 syncer_worklist_len--; 1690 mtx_unlock(&sync_mtx); 1691 } 1692 bp->b_vp = NULL; 1693 bp->b_bufobj = NULL; 1694 BO_UNLOCK(bo); 1695 vdrop(vp); 1696} 1697 1698/* 1699 * Add an item to the syncer work queue. 1700 */ 1701static void 1702vn_syncer_add_to_worklist(struct bufobj *bo, int delay) 1703{ 1704 int slot; 1705 1706 ASSERT_BO_WLOCKED(bo); 1707 1708 mtx_lock(&sync_mtx); 1709 if (bo->bo_flag & BO_ONWORKLST) 1710 LIST_REMOVE(bo, bo_synclist); 1711 else { 1712 bo->bo_flag |= BO_ONWORKLST; 1713 syncer_worklist_len++; 1714 } 1715 1716 if (delay > syncer_maxdelay - 2) 1717 delay = syncer_maxdelay - 2; 1718 slot = (syncer_delayno + delay) & syncer_mask; 1719 1720 LIST_INSERT_HEAD(&syncer_workitem_pending[slot], bo, bo_synclist); 1721 mtx_unlock(&sync_mtx); 1722} 1723 1724static int 1725sysctl_vfs_worklist_len(SYSCTL_HANDLER_ARGS) 1726{ 1727 int error, len; 1728 1729 mtx_lock(&sync_mtx); 1730 len = syncer_worklist_len - sync_vnode_count; 1731 mtx_unlock(&sync_mtx); 1732 error = SYSCTL_OUT(req, &len, sizeof(len)); 1733 return (error); 1734} 1735 1736SYSCTL_PROC(_vfs, OID_AUTO, worklist_len, CTLTYPE_INT | CTLFLAG_RD, NULL, 0, 1737 sysctl_vfs_worklist_len, "I", "Syncer thread worklist length"); 1738 1739static struct proc *updateproc; 1740static void sched_sync(void); 1741static struct kproc_desc up_kp = { 1742 "syncer", 1743 sched_sync, 1744 &updateproc 1745}; 1746SYSINIT(syncer, SI_SUB_KTHREAD_UPDATE, SI_ORDER_FIRST, kproc_start, &up_kp); 1747 1748static int 1749sync_vnode(struct synclist *slp, struct bufobj **bo, struct thread *td) 1750{ 1751 struct vnode *vp; 1752 struct mount *mp; 1753 1754 *bo = LIST_FIRST(slp); 1755 if (*bo == NULL) 1756 return (0); 1757 vp = (*bo)->__bo_vnode; /* XXX */ 1758 if (VOP_ISLOCKED(vp) != 0 || VI_TRYLOCK(vp) == 0) 1759 return (1); 1760 /* 1761 * We use vhold in case the vnode does not 1762 * successfully sync. vhold prevents the vnode from 1763 * going away when we unlock the sync_mtx so that 1764 * we can acquire the vnode interlock. 1765 */ 1766 vholdl(vp); 1767 mtx_unlock(&sync_mtx); 1768 VI_UNLOCK(vp); 1769 if (vn_start_write(vp, &mp, V_NOWAIT) != 0) { 1770 vdrop(vp); 1771 mtx_lock(&sync_mtx); 1772 return (*bo == LIST_FIRST(slp)); 1773 } 1774 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 1775 (void) VOP_FSYNC(vp, MNT_LAZY, td); 1776 VOP_UNLOCK(vp, 0); 1777 vn_finished_write(mp); 1778 BO_LOCK(*bo); 1779 if (((*bo)->bo_flag & BO_ONWORKLST) != 0) { 1780 /* 1781 * Put us back on the worklist. The worklist 1782 * routine will remove us from our current 1783 * position and then add us back in at a later 1784 * position. 1785 */ 1786 vn_syncer_add_to_worklist(*bo, syncdelay); 1787 } 1788 BO_UNLOCK(*bo); 1789 vdrop(vp); 1790 mtx_lock(&sync_mtx); 1791 return (0); 1792} 1793 1794static int first_printf = 1; 1795 1796/* 1797 * System filesystem synchronizer daemon. 1798 */ 1799static void 1800sched_sync(void) 1801{ 1802 struct synclist *next, *slp; 1803 struct bufobj *bo; 1804 long starttime; 1805 struct thread *td = curthread; 1806 int last_work_seen; 1807 int net_worklist_len; 1808 int syncer_final_iter; 1809 int error; 1810 1811 last_work_seen = 0; 1812 syncer_final_iter = 0; 1813 syncer_state = SYNCER_RUNNING; 1814 starttime = time_uptime; 1815 td->td_pflags |= TDP_NORUNNINGBUF; 1816 1817 EVENTHANDLER_REGISTER(shutdown_pre_sync, syncer_shutdown, td->td_proc, 1818 SHUTDOWN_PRI_LAST); 1819 1820 mtx_lock(&sync_mtx); 1821 for (;;) { 1822 if (syncer_state == SYNCER_FINAL_DELAY && 1823 syncer_final_iter == 0) { 1824 mtx_unlock(&sync_mtx); 1825 kproc_suspend_check(td->td_proc); 1826 mtx_lock(&sync_mtx); 1827 } 1828 net_worklist_len = syncer_worklist_len - sync_vnode_count; 1829 if (syncer_state != SYNCER_RUNNING && 1830 starttime != time_uptime) { 1831 if (first_printf) { 1832 printf("\nSyncing disks, vnodes remaining..."); 1833 first_printf = 0; 1834 } 1835 printf("%d ", net_worklist_len); 1836 } 1837 starttime = time_uptime; 1838 1839 /* 1840 * Push files whose dirty time has expired. Be careful 1841 * of interrupt race on slp queue. 1842 * 1843 * Skip over empty worklist slots when shutting down. 1844 */ 1845 do { 1846 slp = &syncer_workitem_pending[syncer_delayno]; 1847 syncer_delayno += 1; 1848 if (syncer_delayno == syncer_maxdelay) 1849 syncer_delayno = 0; 1850 next = &syncer_workitem_pending[syncer_delayno]; 1851 /* 1852 * If the worklist has wrapped since the 1853 * it was emptied of all but syncer vnodes, 1854 * switch to the FINAL_DELAY state and run 1855 * for one more second. 1856 */ 1857 if (syncer_state == SYNCER_SHUTTING_DOWN && 1858 net_worklist_len == 0 && 1859 last_work_seen == syncer_delayno) { 1860 syncer_state = SYNCER_FINAL_DELAY; 1861 syncer_final_iter = SYNCER_SHUTDOWN_SPEEDUP; 1862 } 1863 } while (syncer_state != SYNCER_RUNNING && LIST_EMPTY(slp) && 1864 syncer_worklist_len > 0); 1865 1866 /* 1867 * Keep track of the last time there was anything 1868 * on the worklist other than syncer vnodes. 1869 * Return to the SHUTTING_DOWN state if any 1870 * new work appears. 1871 */ 1872 if (net_worklist_len > 0 || syncer_state == SYNCER_RUNNING) 1873 last_work_seen = syncer_delayno; 1874 if (net_worklist_len > 0 && syncer_state == SYNCER_FINAL_DELAY) 1875 syncer_state = SYNCER_SHUTTING_DOWN; 1876 while (!LIST_EMPTY(slp)) { 1877 error = sync_vnode(slp, &bo, td); 1878 if (error == 1) { 1879 LIST_REMOVE(bo, bo_synclist); 1880 LIST_INSERT_HEAD(next, bo, bo_synclist); 1881 continue; 1882 } 1883 1884 if (first_printf == 0) 1885 wdog_kern_pat(WD_LASTVAL); 1886 1887 } 1888 if (syncer_state == SYNCER_FINAL_DELAY && syncer_final_iter > 0) 1889 syncer_final_iter--; 1890 /* 1891 * The variable rushjob allows the kernel to speed up the 1892 * processing of the filesystem syncer process. A rushjob 1893 * value of N tells the filesystem syncer to process the next 1894 * N seconds worth of work on its queue ASAP. Currently rushjob 1895 * is used by the soft update code to speed up the filesystem 1896 * syncer process when the incore state is getting so far 1897 * ahead of the disk that the kernel memory pool is being 1898 * threatened with exhaustion. 1899 */ 1900 if (rushjob > 0) { 1901 rushjob -= 1; 1902 continue; 1903 } 1904 /* 1905 * Just sleep for a short period of time between 1906 * iterations when shutting down to allow some I/O 1907 * to happen. 1908 * 1909 * If it has taken us less than a second to process the 1910 * current work, then wait. Otherwise start right over 1911 * again. We can still lose time if any single round 1912 * takes more than two seconds, but it does not really 1913 * matter as we are just trying to generally pace the 1914 * filesystem activity. 1915 */ 1916 if (syncer_state != SYNCER_RUNNING || 1917 time_uptime == starttime) { 1918 thread_lock(td); 1919 sched_prio(td, PPAUSE); 1920 thread_unlock(td); 1921 } 1922 if (syncer_state != SYNCER_RUNNING) 1923 cv_timedwait(&sync_wakeup, &sync_mtx, 1924 hz / SYNCER_SHUTDOWN_SPEEDUP); 1925 else if (time_uptime == starttime) 1926 cv_timedwait(&sync_wakeup, &sync_mtx, hz); 1927 } 1928} 1929 1930/* 1931 * Request the syncer daemon to speed up its work. 1932 * We never push it to speed up more than half of its 1933 * normal turn time, otherwise it could take over the cpu. 1934 */ 1935int 1936speedup_syncer(void) 1937{ 1938 int ret = 0; 1939 1940 mtx_lock(&sync_mtx); 1941 if (rushjob < syncdelay / 2) { 1942 rushjob += 1; 1943 stat_rush_requests += 1; 1944 ret = 1; 1945 } 1946 mtx_unlock(&sync_mtx); 1947 cv_broadcast(&sync_wakeup); 1948 return (ret); 1949} 1950 1951/* 1952 * Tell the syncer to speed up its work and run though its work 1953 * list several times, then tell it to shut down. 1954 */ 1955static void 1956syncer_shutdown(void *arg, int howto) 1957{ 1958 1959 if (howto & RB_NOSYNC) 1960 return; 1961 mtx_lock(&sync_mtx); 1962 syncer_state = SYNCER_SHUTTING_DOWN; 1963 rushjob = 0; 1964 mtx_unlock(&sync_mtx); 1965 cv_broadcast(&sync_wakeup); 1966 kproc_shutdown(arg, howto); 1967} 1968 1969void 1970syncer_suspend(void) 1971{ 1972 1973 syncer_shutdown(updateproc, 0); 1974} 1975 1976void 1977syncer_resume(void) 1978{ 1979 1980 mtx_lock(&sync_mtx); 1981 first_printf = 1; 1982 syncer_state = SYNCER_RUNNING; 1983 mtx_unlock(&sync_mtx); 1984 cv_broadcast(&sync_wakeup); 1985 kproc_resume(updateproc); 1986} 1987 1988/* 1989 * Reassign a buffer from one vnode to another. 1990 * Used to assign file specific control information 1991 * (indirect blocks) to the vnode to which they belong. 1992 */ 1993void 1994reassignbuf(struct buf *bp) 1995{ 1996 struct vnode *vp; 1997 struct bufobj *bo; 1998 int delay; 1999#ifdef INVARIANTS 2000 struct bufv *bv; 2001#endif 2002 2003 vp = bp->b_vp; 2004 bo = bp->b_bufobj; 2005 ++reassignbufcalls; 2006 2007 CTR3(KTR_BUF, "reassignbuf(%p) vp %p flags %X", 2008 bp, bp->b_vp, bp->b_flags); 2009 /* 2010 * B_PAGING flagged buffers cannot be reassigned because their vp 2011 * is not fully linked in. 2012 */ 2013 if (bp->b_flags & B_PAGING) 2014 panic("cannot reassign paging buffer"); 2015 2016 /* 2017 * Delete from old vnode list, if on one. 2018 */ 2019 BO_LOCK(bo); 2020 if (bp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN)) 2021 buf_vlist_remove(bp); 2022 else 2023 panic("reassignbuf: Buffer %p not on queue.", bp); 2024 /* 2025 * If dirty, put on list of dirty buffers; otherwise insert onto list 2026 * of clean buffers. 2027 */ 2028 if (bp->b_flags & B_DELWRI) { 2029 if ((bo->bo_flag & BO_ONWORKLST) == 0) { 2030 switch (vp->v_type) { 2031 case VDIR: 2032 delay = dirdelay; 2033 break; 2034 case VCHR: 2035 delay = metadelay; 2036 break; 2037 default: 2038 delay = filedelay; 2039 } 2040 vn_syncer_add_to_worklist(bo, delay); 2041 } 2042 buf_vlist_add(bp, bo, BX_VNDIRTY); 2043 } else { 2044 buf_vlist_add(bp, bo, BX_VNCLEAN); 2045 2046 if ((bo->bo_flag & BO_ONWORKLST) && bo->bo_dirty.bv_cnt == 0) { 2047 mtx_lock(&sync_mtx); 2048 LIST_REMOVE(bo, bo_synclist); 2049 syncer_worklist_len--; 2050 mtx_unlock(&sync_mtx); 2051 bo->bo_flag &= ~BO_ONWORKLST; 2052 } 2053 } 2054#ifdef INVARIANTS 2055 bv = &bo->bo_clean; 2056 bp = TAILQ_FIRST(&bv->bv_hd); 2057 KASSERT(bp == NULL || bp->b_bufobj == bo, 2058 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 2059 bp = TAILQ_LAST(&bv->bv_hd, buflists); 2060 KASSERT(bp == NULL || bp->b_bufobj == bo, 2061 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 2062 bv = &bo->bo_dirty; 2063 bp = TAILQ_FIRST(&bv->bv_hd); 2064 KASSERT(bp == NULL || bp->b_bufobj == bo, 2065 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 2066 bp = TAILQ_LAST(&bv->bv_hd, buflists); 2067 KASSERT(bp == NULL || bp->b_bufobj == bo, 2068 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 2069#endif 2070 BO_UNLOCK(bo); 2071} 2072 2073/* 2074 * Increment the use and hold counts on the vnode, taking care to reference 2075 * the driver's usecount if this is a chardev. The vholdl() will remove 2076 * the vnode from the free list if it is presently free. Requires the 2077 * vnode interlock and returns with it held. 2078 */ 2079static void 2080v_incr_usecount(struct vnode *vp) 2081{ 2082 2083 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2084 vholdl(vp); 2085 vp->v_usecount++; 2086 if (vp->v_type == VCHR && vp->v_rdev != NULL) { 2087 dev_lock(); 2088 vp->v_rdev->si_usecount++; 2089 dev_unlock(); 2090 } 2091} 2092 2093/* 2094 * Turn a holdcnt into a use+holdcnt such that only one call to 2095 * v_decr_usecount is needed. 2096 */ 2097static void 2098v_upgrade_usecount(struct vnode *vp) 2099{ 2100 2101 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2102 vp->v_usecount++; 2103 if (vp->v_type == VCHR && vp->v_rdev != NULL) { 2104 dev_lock(); 2105 vp->v_rdev->si_usecount++; 2106 dev_unlock(); 2107 } 2108} 2109 2110/* 2111 * Decrement the vnode use and hold count along with the driver's usecount 2112 * if this is a chardev. The vdropl() below releases the vnode interlock 2113 * as it may free the vnode. 2114 */ 2115static void 2116v_decr_usecount(struct vnode *vp) 2117{ 2118 2119 ASSERT_VI_LOCKED(vp, __FUNCTION__); 2120 VNASSERT(vp->v_usecount > 0, vp, 2121 ("v_decr_usecount: negative usecount")); 2122 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2123 vp->v_usecount--; 2124 if (vp->v_type == VCHR && vp->v_rdev != NULL) { 2125 dev_lock(); 2126 vp->v_rdev->si_usecount--; 2127 dev_unlock(); 2128 } 2129 vdropl(vp); 2130} 2131 2132/* 2133 * Decrement only the use count and driver use count. This is intended to 2134 * be paired with a follow on vdropl() to release the remaining hold count. 2135 * In this way we may vgone() a vnode with a 0 usecount without risk of 2136 * having it end up on a free list because the hold count is kept above 0. 2137 */ 2138static void 2139v_decr_useonly(struct vnode *vp) 2140{ 2141 2142 ASSERT_VI_LOCKED(vp, __FUNCTION__); 2143 VNASSERT(vp->v_usecount > 0, vp, 2144 ("v_decr_useonly: negative usecount")); 2145 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2146 vp->v_usecount--; 2147 if (vp->v_type == VCHR && vp->v_rdev != NULL) { 2148 dev_lock(); 2149 vp->v_rdev->si_usecount--; 2150 dev_unlock(); 2151 } 2152} 2153 2154/* 2155 * Grab a particular vnode from the free list, increment its 2156 * reference count and lock it. VI_DOOMED is set if the vnode 2157 * is being destroyed. Only callers who specify LK_RETRY will 2158 * see doomed vnodes. If inactive processing was delayed in 2159 * vput try to do it here. 2160 */ 2161int 2162vget(struct vnode *vp, int flags, struct thread *td) 2163{ 2164 int error; 2165 2166 error = 0; 2167 VNASSERT((flags & LK_TYPE_MASK) != 0, vp, 2168 ("vget: invalid lock operation")); 2169 CTR3(KTR_VFS, "%s: vp %p with flags %d", __func__, vp, flags); 2170 2171 if ((flags & LK_INTERLOCK) == 0) 2172 VI_LOCK(vp); 2173 vholdl(vp); 2174 if ((error = vn_lock(vp, flags | LK_INTERLOCK)) != 0) { 2175 vdrop(vp); 2176 CTR2(KTR_VFS, "%s: impossible to lock vnode %p", __func__, 2177 vp); 2178 return (error); 2179 } 2180 if (vp->v_iflag & VI_DOOMED && (flags & LK_RETRY) == 0) 2181 panic("vget: vn_lock failed to return ENOENT\n"); 2182 VI_LOCK(vp); 2183 /* Upgrade our holdcnt to a usecount. */ 2184 v_upgrade_usecount(vp); 2185 /* 2186 * We don't guarantee that any particular close will 2187 * trigger inactive processing so just make a best effort 2188 * here at preventing a reference to a removed file. If 2189 * we don't succeed no harm is done. 2190 */ 2191 if (vp->v_iflag & VI_OWEINACT) { 2192 if (VOP_ISLOCKED(vp) == LK_EXCLUSIVE && 2193 (flags & LK_NOWAIT) == 0) 2194 vinactive(vp, td); 2195 vp->v_iflag &= ~VI_OWEINACT; 2196 } 2197 VI_UNLOCK(vp); 2198 return (0); 2199} 2200 2201/* 2202 * Increase the reference count of a vnode. 2203 */ 2204void 2205vref(struct vnode *vp) 2206{ 2207 2208 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2209 VI_LOCK(vp); 2210 v_incr_usecount(vp); 2211 VI_UNLOCK(vp); 2212} 2213 2214/* 2215 * Return reference count of a vnode. 2216 * 2217 * The results of this call are only guaranteed when some mechanism other 2218 * than the VI lock is used to stop other processes from gaining references 2219 * to the vnode. This may be the case if the caller holds the only reference. 2220 * This is also useful when stale data is acceptable as race conditions may 2221 * be accounted for by some other means. 2222 */ 2223int 2224vrefcnt(struct vnode *vp) 2225{ 2226 int usecnt; 2227 2228 VI_LOCK(vp); 2229 usecnt = vp->v_usecount; 2230 VI_UNLOCK(vp); 2231 2232 return (usecnt); 2233} 2234 2235#define VPUTX_VRELE 1 2236#define VPUTX_VPUT 2 2237#define VPUTX_VUNREF 3 2238 2239static void 2240vputx(struct vnode *vp, int func) 2241{ 2242 int error; 2243 2244 KASSERT(vp != NULL, ("vputx: null vp")); 2245 if (func == VPUTX_VUNREF) 2246 ASSERT_VOP_LOCKED(vp, "vunref"); 2247 else if (func == VPUTX_VPUT) 2248 ASSERT_VOP_LOCKED(vp, "vput"); 2249 else 2250 KASSERT(func == VPUTX_VRELE, ("vputx: wrong func")); 2251 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2252 VI_LOCK(vp); 2253 2254 /* Skip this v_writecount check if we're going to panic below. */ 2255 VNASSERT(vp->v_writecount < vp->v_usecount || vp->v_usecount < 1, vp, 2256 ("vputx: missed vn_close")); 2257 error = 0; 2258 2259 if (vp->v_usecount > 1 || ((vp->v_iflag & VI_DOINGINACT) && 2260 vp->v_usecount == 1)) { 2261 if (func == VPUTX_VPUT) 2262 VOP_UNLOCK(vp, 0); 2263 v_decr_usecount(vp); 2264 return; 2265 } 2266 2267 if (vp->v_usecount != 1) { 2268 vprint("vputx: negative ref count", vp); 2269 panic("vputx: negative ref cnt"); 2270 } 2271 CTR2(KTR_VFS, "%s: return vnode %p to the freelist", __func__, vp); 2272 /* 2273 * We want to hold the vnode until the inactive finishes to 2274 * prevent vgone() races. We drop the use count here and the 2275 * hold count below when we're done. 2276 */ 2277 v_decr_useonly(vp); 2278 /* 2279 * We must call VOP_INACTIVE with the node locked. Mark 2280 * as VI_DOINGINACT to avoid recursion. 2281 */ 2282 vp->v_iflag |= VI_OWEINACT; 2283 switch (func) { 2284 case VPUTX_VRELE: 2285 error = vn_lock(vp, LK_EXCLUSIVE | LK_INTERLOCK); 2286 VI_LOCK(vp); 2287 break; 2288 case VPUTX_VPUT: 2289 if (VOP_ISLOCKED(vp) != LK_EXCLUSIVE) { 2290 error = VOP_LOCK(vp, LK_UPGRADE | LK_INTERLOCK | 2291 LK_NOWAIT); 2292 VI_LOCK(vp); 2293 } 2294 break; 2295 case VPUTX_VUNREF: 2296 if (VOP_ISLOCKED(vp) != LK_EXCLUSIVE) { 2297 error = VOP_LOCK(vp, LK_TRYUPGRADE | LK_INTERLOCK); 2298 VI_LOCK(vp); 2299 } 2300 break; 2301 } 2302 if (vp->v_usecount > 0) 2303 vp->v_iflag &= ~VI_OWEINACT; 2304 if (error == 0) { 2305 if (vp->v_iflag & VI_OWEINACT) 2306 vinactive(vp, curthread); 2307 if (func != VPUTX_VUNREF) 2308 VOP_UNLOCK(vp, 0); 2309 } 2310 vdropl(vp); 2311} 2312 2313/* 2314 * Vnode put/release. 2315 * If count drops to zero, call inactive routine and return to freelist. 2316 */ 2317void 2318vrele(struct vnode *vp) 2319{ 2320 2321 vputx(vp, VPUTX_VRELE); 2322} 2323 2324/* 2325 * Release an already locked vnode. This give the same effects as 2326 * unlock+vrele(), but takes less time and avoids releasing and 2327 * re-aquiring the lock (as vrele() acquires the lock internally.) 2328 */ 2329void 2330vput(struct vnode *vp) 2331{ 2332 2333 vputx(vp, VPUTX_VPUT); 2334} 2335 2336/* 2337 * Release an exclusively locked vnode. Do not unlock the vnode lock. 2338 */ 2339void 2340vunref(struct vnode *vp) 2341{ 2342 2343 vputx(vp, VPUTX_VUNREF); 2344} 2345 2346/* 2347 * Somebody doesn't want the vnode recycled. 2348 */ 2349void 2350vhold(struct vnode *vp) 2351{ 2352 2353 VI_LOCK(vp); 2354 vholdl(vp); 2355 VI_UNLOCK(vp); 2356} 2357 2358/* 2359 * Increase the hold count and activate if this is the first reference. 2360 */ 2361void 2362vholdl(struct vnode *vp) 2363{ 2364 struct mount *mp; 2365 2366 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2367#ifdef INVARIANTS 2368 /* getnewvnode() calls v_incr_usecount() without holding interlock. */ 2369 if (vp->v_type != VNON || vp->v_data != NULL) 2370 ASSERT_VI_LOCKED(vp, "vholdl"); 2371#endif 2372 vp->v_holdcnt++; 2373 if ((vp->v_iflag & VI_FREE) == 0) 2374 return; 2375 VNASSERT(vp->v_holdcnt == 1, vp, ("vholdl: wrong hold count")); 2376 VNASSERT(vp->v_op != NULL, vp, ("vholdl: vnode already reclaimed.")); 2377 /* 2378 * Remove a vnode from the free list, mark it as in use, 2379 * and put it on the active list. 2380 */ 2381 mtx_lock(&vnode_free_list_mtx); 2382 TAILQ_REMOVE(&vnode_free_list, vp, v_actfreelist); 2383 freevnodes--; 2384 vp->v_iflag &= ~(VI_FREE|VI_AGE); 2385 KASSERT((vp->v_iflag & VI_ACTIVE) == 0, 2386 ("Activating already active vnode")); 2387 vp->v_iflag |= VI_ACTIVE; 2388 mp = vp->v_mount; 2389 TAILQ_INSERT_HEAD(&mp->mnt_activevnodelist, vp, v_actfreelist); 2390 mp->mnt_activevnodelistsize++; 2391 mtx_unlock(&vnode_free_list_mtx); 2392} 2393 2394/* 2395 * Note that there is one less who cares about this vnode. 2396 * vdrop() is the opposite of vhold(). 2397 */ 2398void 2399vdrop(struct vnode *vp) 2400{ 2401 2402 VI_LOCK(vp); 2403 vdropl(vp); 2404} 2405 2406/* 2407 * Drop the hold count of the vnode. If this is the last reference to 2408 * the vnode we place it on the free list unless it has been vgone'd 2409 * (marked VI_DOOMED) in which case we will free it. 2410 */ 2411void 2412vdropl(struct vnode *vp) 2413{ 2414 struct bufobj *bo; 2415 struct mount *mp; 2416 int active; 2417 2418 ASSERT_VI_LOCKED(vp, "vdropl"); 2419 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2420 if (vp->v_holdcnt <= 0) 2421 panic("vdrop: holdcnt %d", vp->v_holdcnt); 2422 vp->v_holdcnt--; 2423 if (vp->v_holdcnt > 0) { 2424 VI_UNLOCK(vp); 2425 return; 2426 } 2427 if ((vp->v_iflag & VI_DOOMED) == 0) { 2428 /* 2429 * Mark a vnode as free: remove it from its active list 2430 * and put it up for recycling on the freelist. 2431 */ 2432 VNASSERT(vp->v_op != NULL, vp, 2433 ("vdropl: vnode already reclaimed.")); 2434 VNASSERT((vp->v_iflag & VI_FREE) == 0, vp, 2435 ("vnode already free")); 2436 VNASSERT(vp->v_holdcnt == 0, vp, 2437 ("vdropl: freeing when we shouldn't")); 2438 active = vp->v_iflag & VI_ACTIVE; 2439 if ((vp->v_iflag & VI_OWEINACT) == 0) { 2440 vp->v_iflag &= ~VI_ACTIVE; 2441 mp = vp->v_mount; 2442 mtx_lock(&vnode_free_list_mtx); 2443 if (active) { 2444 TAILQ_REMOVE(&mp->mnt_activevnodelist, vp, 2445 v_actfreelist); 2446 mp->mnt_activevnodelistsize--; 2447 } 2448 if (vp->v_iflag & VI_AGE) { 2449 TAILQ_INSERT_HEAD(&vnode_free_list, vp, 2450 v_actfreelist); 2451 } else { 2452 TAILQ_INSERT_TAIL(&vnode_free_list, vp, 2453 v_actfreelist); 2454 } 2455 freevnodes++; 2456 vp->v_iflag &= ~VI_AGE; 2457 vp->v_iflag |= VI_FREE; 2458 mtx_unlock(&vnode_free_list_mtx); 2459 } else { 2460 atomic_add_long(&free_owe_inact, 1); 2461 } 2462 VI_UNLOCK(vp); 2463 return; 2464 } 2465 /* 2466 * The vnode has been marked for destruction, so free it. 2467 */ 2468 CTR2(KTR_VFS, "%s: destroying the vnode %p", __func__, vp); 2469 atomic_subtract_long(&numvnodes, 1); 2470 bo = &vp->v_bufobj; 2471 VNASSERT((vp->v_iflag & VI_FREE) == 0, vp, 2472 ("cleaned vnode still on the free list.")); 2473 VNASSERT(vp->v_data == NULL, vp, ("cleaned vnode isn't")); 2474 VNASSERT(vp->v_holdcnt == 0, vp, ("Non-zero hold count")); 2475 VNASSERT(vp->v_usecount == 0, vp, ("Non-zero use count")); 2476 VNASSERT(vp->v_writecount == 0, vp, ("Non-zero write count")); 2477 VNASSERT(bo->bo_numoutput == 0, vp, ("Clean vnode has pending I/O's")); 2478 VNASSERT(bo->bo_clean.bv_cnt == 0, vp, ("cleanbufcnt not 0")); 2479 VNASSERT(pctrie_is_empty(&bo->bo_clean.bv_root), vp, 2480 ("clean blk trie not empty")); 2481 VNASSERT(bo->bo_dirty.bv_cnt == 0, vp, ("dirtybufcnt not 0")); 2482 VNASSERT(pctrie_is_empty(&bo->bo_dirty.bv_root), vp, 2483 ("dirty blk trie not empty")); 2484 VNASSERT(TAILQ_EMPTY(&vp->v_cache_dst), vp, ("vp has namecache dst")); 2485 VNASSERT(LIST_EMPTY(&vp->v_cache_src), vp, ("vp has namecache src")); 2486 VNASSERT(vp->v_cache_dd == NULL, vp, ("vp has namecache for ..")); 2487 VI_UNLOCK(vp); 2488#ifdef MAC 2489 mac_vnode_destroy(vp); 2490#endif 2491 if (vp->v_pollinfo != NULL) 2492 destroy_vpollinfo(vp->v_pollinfo); 2493#ifdef INVARIANTS 2494 /* XXX Elsewhere we detect an already freed vnode via NULL v_op. */ 2495 vp->v_op = NULL; 2496#endif 2497 rangelock_destroy(&vp->v_rl); 2498 lockdestroy(vp->v_vnlock); 2499 mtx_destroy(&vp->v_interlock); 2500 rw_destroy(BO_LOCKPTR(bo)); 2501 uma_zfree(vnode_zone, vp); 2502} 2503 2504/* 2505 * Call VOP_INACTIVE on the vnode and manage the DOINGINACT and OWEINACT 2506 * flags. DOINGINACT prevents us from recursing in calls to vinactive. 2507 * OWEINACT tracks whether a vnode missed a call to inactive due to a 2508 * failed lock upgrade. 2509 */ 2510void 2511vinactive(struct vnode *vp, struct thread *td) 2512{ 2513 struct vm_object *obj; 2514 2515 ASSERT_VOP_ELOCKED(vp, "vinactive"); 2516 ASSERT_VI_LOCKED(vp, "vinactive"); 2517 VNASSERT((vp->v_iflag & VI_DOINGINACT) == 0, vp, 2518 ("vinactive: recursed on VI_DOINGINACT")); 2519 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2520 vp->v_iflag |= VI_DOINGINACT; 2521 vp->v_iflag &= ~VI_OWEINACT; 2522 VI_UNLOCK(vp); 2523 /* 2524 * Before moving off the active list, we must be sure that any 2525 * modified pages are on the vnode's dirty list since these will 2526 * no longer be checked once the vnode is on the inactive list. 2527 * Because the vnode vm object keeps a hold reference on the vnode 2528 * if there is at least one resident non-cached page, the vnode 2529 * cannot leave the active list without the page cleanup done. 2530 */ 2531 obj = vp->v_object; 2532 if (obj != NULL && (obj->flags & OBJ_MIGHTBEDIRTY) != 0) { 2533 VM_OBJECT_WLOCK(obj); 2534 vm_object_page_clean(obj, 0, 0, OBJPC_NOSYNC); 2535 VM_OBJECT_WUNLOCK(obj); 2536 } 2537 VOP_INACTIVE(vp, td); 2538 VI_LOCK(vp); 2539 VNASSERT(vp->v_iflag & VI_DOINGINACT, vp, 2540 ("vinactive: lost VI_DOINGINACT")); 2541 vp->v_iflag &= ~VI_DOINGINACT; 2542} 2543 2544/* 2545 * Remove any vnodes in the vnode table belonging to mount point mp. 2546 * 2547 * If FORCECLOSE is not specified, there should not be any active ones, 2548 * return error if any are found (nb: this is a user error, not a 2549 * system error). If FORCECLOSE is specified, detach any active vnodes 2550 * that are found. 2551 * 2552 * If WRITECLOSE is set, only flush out regular file vnodes open for 2553 * writing. 2554 * 2555 * SKIPSYSTEM causes any vnodes marked VV_SYSTEM to be skipped. 2556 * 2557 * `rootrefs' specifies the base reference count for the root vnode 2558 * of this filesystem. The root vnode is considered busy if its 2559 * v_usecount exceeds this value. On a successful return, vflush(, td) 2560 * will call vrele() on the root vnode exactly rootrefs times. 2561 * If the SKIPSYSTEM or WRITECLOSE flags are specified, rootrefs must 2562 * be zero. 2563 */ 2564#ifdef DIAGNOSTIC 2565static int busyprt = 0; /* print out busy vnodes */ 2566SYSCTL_INT(_debug, OID_AUTO, busyprt, CTLFLAG_RW, &busyprt, 0, "Print out busy vnodes"); 2567#endif 2568 2569int 2570vflush(struct mount *mp, int rootrefs, int flags, struct thread *td) 2571{ 2572 struct vnode *vp, *mvp, *rootvp = NULL; 2573 struct vattr vattr; 2574 int busy = 0, error; 2575 2576 CTR4(KTR_VFS, "%s: mp %p with rootrefs %d and flags %d", __func__, mp, 2577 rootrefs, flags); 2578 if (rootrefs > 0) { 2579 KASSERT((flags & (SKIPSYSTEM | WRITECLOSE)) == 0, 2580 ("vflush: bad args")); 2581 /* 2582 * Get the filesystem root vnode. We can vput() it 2583 * immediately, since with rootrefs > 0, it won't go away. 2584 */ 2585 if ((error = VFS_ROOT(mp, LK_EXCLUSIVE, &rootvp)) != 0) { 2586 CTR2(KTR_VFS, "%s: vfs_root lookup failed with %d", 2587 __func__, error); 2588 return (error); 2589 } 2590 vput(rootvp); 2591 } 2592loop: 2593 MNT_VNODE_FOREACH_ALL(vp, mp, mvp) { 2594 vholdl(vp); 2595 error = vn_lock(vp, LK_INTERLOCK | LK_EXCLUSIVE); 2596 if (error) { 2597 vdrop(vp); 2598 MNT_VNODE_FOREACH_ALL_ABORT(mp, mvp); 2599 goto loop; 2600 } 2601 /* 2602 * Skip over a vnodes marked VV_SYSTEM. 2603 */ 2604 if ((flags & SKIPSYSTEM) && (vp->v_vflag & VV_SYSTEM)) { 2605 VOP_UNLOCK(vp, 0); 2606 vdrop(vp); 2607 continue; 2608 } 2609 /* 2610 * If WRITECLOSE is set, flush out unlinked but still open 2611 * files (even if open only for reading) and regular file 2612 * vnodes open for writing. 2613 */ 2614 if (flags & WRITECLOSE) { 2615 if (vp->v_object != NULL) { 2616 VM_OBJECT_WLOCK(vp->v_object); 2617 vm_object_page_clean(vp->v_object, 0, 0, 0); 2618 VM_OBJECT_WUNLOCK(vp->v_object); 2619 } 2620 error = VOP_FSYNC(vp, MNT_WAIT, td); 2621 if (error != 0) { 2622 VOP_UNLOCK(vp, 0); 2623 vdrop(vp); 2624 MNT_VNODE_FOREACH_ALL_ABORT(mp, mvp); 2625 return (error); 2626 } 2627 error = VOP_GETATTR(vp, &vattr, td->td_ucred); 2628 VI_LOCK(vp); 2629 2630 if ((vp->v_type == VNON || 2631 (error == 0 && vattr.va_nlink > 0)) && 2632 (vp->v_writecount == 0 || vp->v_type != VREG)) { 2633 VOP_UNLOCK(vp, 0); 2634 vdropl(vp); 2635 continue; 2636 } 2637 } else 2638 VI_LOCK(vp); 2639 /* 2640 * With v_usecount == 0, all we need to do is clear out the 2641 * vnode data structures and we are done. 2642 * 2643 * If FORCECLOSE is set, forcibly close the vnode. 2644 */ 2645 if (vp->v_usecount == 0 || (flags & FORCECLOSE)) { 2646 VNASSERT(vp->v_usecount == 0 || 2647 vp->v_op != &devfs_specops || 2648 (vp->v_type != VCHR && vp->v_type != VBLK), vp, 2649 ("device VNODE %p is FORCECLOSED", vp)); 2650 vgonel(vp); 2651 } else { 2652 busy++; 2653#ifdef DIAGNOSTIC 2654 if (busyprt) 2655 vprint("vflush: busy vnode", vp); 2656#endif 2657 } 2658 VOP_UNLOCK(vp, 0); 2659 vdropl(vp); 2660 } 2661 if (rootrefs > 0 && (flags & FORCECLOSE) == 0) { 2662 /* 2663 * If just the root vnode is busy, and if its refcount 2664 * is equal to `rootrefs', then go ahead and kill it. 2665 */ 2666 VI_LOCK(rootvp); 2667 KASSERT(busy > 0, ("vflush: not busy")); 2668 VNASSERT(rootvp->v_usecount >= rootrefs, rootvp, 2669 ("vflush: usecount %d < rootrefs %d", 2670 rootvp->v_usecount, rootrefs)); 2671 if (busy == 1 && rootvp->v_usecount == rootrefs) { 2672 VOP_LOCK(rootvp, LK_EXCLUSIVE|LK_INTERLOCK); 2673 vgone(rootvp); 2674 VOP_UNLOCK(rootvp, 0); 2675 busy = 0; 2676 } else 2677 VI_UNLOCK(rootvp); 2678 } 2679 if (busy) { 2680 CTR2(KTR_VFS, "%s: failing as %d vnodes are busy", __func__, 2681 busy); 2682 return (EBUSY); 2683 } 2684 for (; rootrefs > 0; rootrefs--) 2685 vrele(rootvp); 2686 return (0); 2687} 2688 2689/* 2690 * Recycle an unused vnode to the front of the free list. 2691 */ 2692int 2693vrecycle(struct vnode *vp) 2694{ 2695 int recycled; 2696 2697 ASSERT_VOP_ELOCKED(vp, "vrecycle"); 2698 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2699 recycled = 0; 2700 VI_LOCK(vp); 2701 if (vp->v_usecount == 0) { 2702 recycled = 1; 2703 vgonel(vp); 2704 } 2705 VI_UNLOCK(vp); 2706 return (recycled); 2707} 2708 2709/* 2710 * Eliminate all activity associated with a vnode 2711 * in preparation for reuse. 2712 */ 2713void 2714vgone(struct vnode *vp) 2715{ 2716 VI_LOCK(vp); 2717 vgonel(vp); 2718 VI_UNLOCK(vp); 2719} 2720 2721static void 2722notify_lowervp_vfs_dummy(struct mount *mp __unused, 2723 struct vnode *lowervp __unused) 2724{ 2725} 2726 2727/* 2728 * Notify upper mounts about reclaimed or unlinked vnode. 2729 */ 2730void 2731vfs_notify_upper(struct vnode *vp, int event) 2732{ 2733 static struct vfsops vgonel_vfsops = { 2734 .vfs_reclaim_lowervp = notify_lowervp_vfs_dummy, 2735 .vfs_unlink_lowervp = notify_lowervp_vfs_dummy, 2736 }; 2737 struct mount *mp, *ump, *mmp; 2738 2739 mp = vp->v_mount; 2740 if (mp == NULL) 2741 return; 2742 2743 MNT_ILOCK(mp); 2744 if (TAILQ_EMPTY(&mp->mnt_uppers)) 2745 goto unlock; 2746 MNT_IUNLOCK(mp); 2747 mmp = malloc(sizeof(struct mount), M_TEMP, M_WAITOK | M_ZERO); 2748 mmp->mnt_op = &vgonel_vfsops; 2749 mmp->mnt_kern_flag |= MNTK_MARKER; 2750 MNT_ILOCK(mp); 2751 mp->mnt_kern_flag |= MNTK_VGONE_UPPER; 2752 for (ump = TAILQ_FIRST(&mp->mnt_uppers); ump != NULL;) { 2753 if ((ump->mnt_kern_flag & MNTK_MARKER) != 0) { 2754 ump = TAILQ_NEXT(ump, mnt_upper_link); 2755 continue; 2756 } 2757 TAILQ_INSERT_AFTER(&mp->mnt_uppers, ump, mmp, mnt_upper_link); 2758 MNT_IUNLOCK(mp); 2759 switch (event) { 2760 case VFS_NOTIFY_UPPER_RECLAIM: 2761 VFS_RECLAIM_LOWERVP(ump, vp); 2762 break; 2763 case VFS_NOTIFY_UPPER_UNLINK: 2764 VFS_UNLINK_LOWERVP(ump, vp); 2765 break; 2766 default: 2767 KASSERT(0, ("invalid event %d", event)); 2768 break; 2769 } 2770 MNT_ILOCK(mp); 2771 ump = TAILQ_NEXT(mmp, mnt_upper_link); 2772 TAILQ_REMOVE(&mp->mnt_uppers, mmp, mnt_upper_link); 2773 } 2774 free(mmp, M_TEMP); 2775 mp->mnt_kern_flag &= ~MNTK_VGONE_UPPER; 2776 if ((mp->mnt_kern_flag & MNTK_VGONE_WAITER) != 0) { 2777 mp->mnt_kern_flag &= ~MNTK_VGONE_WAITER; 2778 wakeup(&mp->mnt_uppers); 2779 } 2780unlock: 2781 MNT_IUNLOCK(mp); 2782} 2783 2784/* 2785 * vgone, with the vp interlock held. 2786 */ 2787void 2788vgonel(struct vnode *vp) 2789{ 2790 struct thread *td; 2791 int oweinact; 2792 int active; 2793 struct mount *mp; 2794 2795 ASSERT_VOP_ELOCKED(vp, "vgonel"); 2796 ASSERT_VI_LOCKED(vp, "vgonel"); 2797 VNASSERT(vp->v_holdcnt, vp, 2798 ("vgonel: vp %p has no reference.", vp)); 2799 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2800 td = curthread; 2801 2802 /* 2803 * Don't vgonel if we're already doomed. 2804 */ 2805 if (vp->v_iflag & VI_DOOMED) 2806 return; 2807 vp->v_iflag |= VI_DOOMED; 2808 2809 /* 2810 * Check to see if the vnode is in use. If so, we have to call 2811 * VOP_CLOSE() and VOP_INACTIVE(). 2812 */ 2813 active = vp->v_usecount; 2814 oweinact = (vp->v_iflag & VI_OWEINACT); 2815 VI_UNLOCK(vp); 2816 vfs_notify_upper(vp, VFS_NOTIFY_UPPER_RECLAIM); 2817 2818 /* 2819 * If purging an active vnode, it must be closed and 2820 * deactivated before being reclaimed. 2821 */ 2822 if (active) 2823 VOP_CLOSE(vp, FNONBLOCK, NOCRED, td); 2824 if (oweinact || active) { 2825 VI_LOCK(vp); 2826 if ((vp->v_iflag & VI_DOINGINACT) == 0) 2827 vinactive(vp, td); 2828 VI_UNLOCK(vp); 2829 } 2830 if (vp->v_type == VSOCK) 2831 vfs_unp_reclaim(vp); 2832 2833 /* 2834 * Clean out any buffers associated with the vnode. 2835 * If the flush fails, just toss the buffers. 2836 */ 2837 mp = NULL; 2838 if (!TAILQ_EMPTY(&vp->v_bufobj.bo_dirty.bv_hd)) 2839 (void) vn_start_secondary_write(vp, &mp, V_WAIT); 2840 if (vinvalbuf(vp, V_SAVE, 0, 0) != 0) { 2841 while (vinvalbuf(vp, 0, 0, 0) != 0) 2842 ; 2843 } 2844#ifdef INVARIANTS 2845 BO_LOCK(&vp->v_bufobj); 2846 KASSERT(TAILQ_EMPTY(&vp->v_bufobj.bo_dirty.bv_hd) && 2847 vp->v_bufobj.bo_dirty.bv_cnt == 0 && 2848 TAILQ_EMPTY(&vp->v_bufobj.bo_clean.bv_hd) && 2849 vp->v_bufobj.bo_clean.bv_cnt == 0, 2850 ("vp %p bufobj not invalidated", vp)); 2851 vp->v_bufobj.bo_flag |= BO_DEAD; 2852 BO_UNLOCK(&vp->v_bufobj); 2853#endif 2854 2855 /* 2856 * Reclaim the vnode. 2857 */ 2858 if (VOP_RECLAIM(vp, td)) 2859 panic("vgone: cannot reclaim"); 2860 if (mp != NULL) 2861 vn_finished_secondary_write(mp); 2862 VNASSERT(vp->v_object == NULL, vp, 2863 ("vop_reclaim left v_object vp=%p, tag=%s", vp, vp->v_tag)); 2864 /* 2865 * Clear the advisory locks and wake up waiting threads. 2866 */ 2867 (void)VOP_ADVLOCKPURGE(vp); 2868 /* 2869 * Delete from old mount point vnode list. 2870 */ 2871 delmntque(vp); 2872 cache_purge(vp); 2873 /* 2874 * Done with purge, reset to the standard lock and invalidate 2875 * the vnode. 2876 */ 2877 VI_LOCK(vp); 2878 vp->v_vnlock = &vp->v_lock; 2879 vp->v_op = &dead_vnodeops; 2880 vp->v_tag = "none"; 2881 vp->v_type = VBAD; 2882} 2883 2884/* 2885 * Calculate the total number of references to a special device. 2886 */ 2887int 2888vcount(struct vnode *vp) 2889{ 2890 int count; 2891 2892 dev_lock(); 2893 count = vp->v_rdev->si_usecount; 2894 dev_unlock(); 2895 return (count); 2896} 2897 2898/* 2899 * Same as above, but using the struct cdev *as argument 2900 */ 2901int 2902count_dev(struct cdev *dev) 2903{ 2904 int count; 2905 2906 dev_lock(); 2907 count = dev->si_usecount; 2908 dev_unlock(); 2909 return(count); 2910} 2911 2912/* 2913 * Print out a description of a vnode. 2914 */ 2915static char *typename[] = 2916{"VNON", "VREG", "VDIR", "VBLK", "VCHR", "VLNK", "VSOCK", "VFIFO", "VBAD", 2917 "VMARKER"}; 2918 2919void 2920vn_printf(struct vnode *vp, const char *fmt, ...) 2921{ 2922 va_list ap; 2923 char buf[256], buf2[16]; 2924 u_long flags; 2925 2926 va_start(ap, fmt); 2927 vprintf(fmt, ap); 2928 va_end(ap); 2929 printf("%p: ", (void *)vp); 2930 printf("tag %s, type %s\n", vp->v_tag, typename[vp->v_type]); 2931 printf(" usecount %d, writecount %d, refcount %d mountedhere %p\n", 2932 vp->v_usecount, vp->v_writecount, vp->v_holdcnt, vp->v_mountedhere); 2933 buf[0] = '\0'; 2934 buf[1] = '\0'; 2935 if (vp->v_vflag & VV_ROOT) 2936 strlcat(buf, "|VV_ROOT", sizeof(buf)); 2937 if (vp->v_vflag & VV_ISTTY) 2938 strlcat(buf, "|VV_ISTTY", sizeof(buf)); 2939 if (vp->v_vflag & VV_NOSYNC) 2940 strlcat(buf, "|VV_NOSYNC", sizeof(buf)); 2941 if (vp->v_vflag & VV_ETERNALDEV) 2942 strlcat(buf, "|VV_ETERNALDEV", sizeof(buf)); 2943 if (vp->v_vflag & VV_CACHEDLABEL) 2944 strlcat(buf, "|VV_CACHEDLABEL", sizeof(buf)); 2945 if (vp->v_vflag & VV_TEXT) 2946 strlcat(buf, "|VV_TEXT", sizeof(buf)); 2947 if (vp->v_vflag & VV_COPYONWRITE) 2948 strlcat(buf, "|VV_COPYONWRITE", sizeof(buf)); 2949 if (vp->v_vflag & VV_SYSTEM) 2950 strlcat(buf, "|VV_SYSTEM", sizeof(buf)); 2951 if (vp->v_vflag & VV_PROCDEP) 2952 strlcat(buf, "|VV_PROCDEP", sizeof(buf)); 2953 if (vp->v_vflag & VV_NOKNOTE) 2954 strlcat(buf, "|VV_NOKNOTE", sizeof(buf)); 2955 if (vp->v_vflag & VV_DELETED) 2956 strlcat(buf, "|VV_DELETED", sizeof(buf)); 2957 if (vp->v_vflag & VV_MD) 2958 strlcat(buf, "|VV_MD", sizeof(buf)); 2959 if (vp->v_vflag & VV_FORCEINSMQ) 2960 strlcat(buf, "|VV_FORCEINSMQ", sizeof(buf)); 2961 flags = vp->v_vflag & ~(VV_ROOT | VV_ISTTY | VV_NOSYNC | VV_ETERNALDEV | 2962 VV_CACHEDLABEL | VV_TEXT | VV_COPYONWRITE | VV_SYSTEM | VV_PROCDEP | 2963 VV_NOKNOTE | VV_DELETED | VV_MD | VV_FORCEINSMQ); 2964 if (flags != 0) { 2965 snprintf(buf2, sizeof(buf2), "|VV(0x%lx)", flags); 2966 strlcat(buf, buf2, sizeof(buf)); 2967 } 2968 if (vp->v_iflag & VI_MOUNT) 2969 strlcat(buf, "|VI_MOUNT", sizeof(buf)); 2970 if (vp->v_iflag & VI_AGE) 2971 strlcat(buf, "|VI_AGE", sizeof(buf)); 2972 if (vp->v_iflag & VI_DOOMED) 2973 strlcat(buf, "|VI_DOOMED", sizeof(buf)); 2974 if (vp->v_iflag & VI_FREE) 2975 strlcat(buf, "|VI_FREE", sizeof(buf)); 2976 if (vp->v_iflag & VI_ACTIVE) 2977 strlcat(buf, "|VI_ACTIVE", sizeof(buf)); 2978 if (vp->v_iflag & VI_DOINGINACT) 2979 strlcat(buf, "|VI_DOINGINACT", sizeof(buf)); 2980 if (vp->v_iflag & VI_OWEINACT) 2981 strlcat(buf, "|VI_OWEINACT", sizeof(buf)); 2982 flags = vp->v_iflag & ~(VI_MOUNT | VI_AGE | VI_DOOMED | VI_FREE | 2983 VI_ACTIVE | VI_DOINGINACT | VI_OWEINACT); 2984 if (flags != 0) { 2985 snprintf(buf2, sizeof(buf2), "|VI(0x%lx)", flags); 2986 strlcat(buf, buf2, sizeof(buf)); 2987 } 2988 printf(" flags (%s)\n", buf + 1); 2989 if (mtx_owned(VI_MTX(vp))) 2990 printf(" VI_LOCKed"); 2991 if (vp->v_object != NULL) 2992 printf(" v_object %p ref %d pages %d " 2993 "cleanbuf %d dirtybuf %d\n", 2994 vp->v_object, vp->v_object->ref_count, 2995 vp->v_object->resident_page_count, 2996 vp->v_bufobj.bo_dirty.bv_cnt, 2997 vp->v_bufobj.bo_clean.bv_cnt); 2998 printf(" "); 2999 lockmgr_printinfo(vp->v_vnlock); 3000 if (vp->v_data != NULL) 3001 VOP_PRINT(vp); 3002} 3003 3004#ifdef DDB 3005/* 3006 * List all of the locked vnodes in the system. 3007 * Called when debugging the kernel. 3008 */ 3009DB_SHOW_COMMAND(lockedvnods, lockedvnodes) 3010{ 3011 struct mount *mp; 3012 struct vnode *vp; 3013 3014 /* 3015 * Note: because this is DDB, we can't obey the locking semantics 3016 * for these structures, which means we could catch an inconsistent 3017 * state and dereference a nasty pointer. Not much to be done 3018 * about that. 3019 */ 3020 db_printf("Locked vnodes\n"); 3021 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 3022 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) { 3023 if (vp->v_type != VMARKER && VOP_ISLOCKED(vp)) 3024 vprint("", vp); 3025 } 3026 } 3027} 3028 3029/* 3030 * Show details about the given vnode. 3031 */ 3032DB_SHOW_COMMAND(vnode, db_show_vnode) 3033{ 3034 struct vnode *vp; 3035 3036 if (!have_addr) 3037 return; 3038 vp = (struct vnode *)addr; 3039 vn_printf(vp, "vnode "); 3040} 3041 3042/* 3043 * Show details about the given mount point. 3044 */ 3045DB_SHOW_COMMAND(mount, db_show_mount) 3046{ 3047 struct mount *mp; 3048 struct vfsopt *opt; 3049 struct statfs *sp; 3050 struct vnode *vp; 3051 char buf[512]; 3052 uint64_t mflags; 3053 u_int flags; 3054 3055 if (!have_addr) { 3056 /* No address given, print short info about all mount points. */ 3057 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 3058 db_printf("%p %s on %s (%s)\n", mp, 3059 mp->mnt_stat.f_mntfromname, 3060 mp->mnt_stat.f_mntonname, 3061 mp->mnt_stat.f_fstypename); 3062 if (db_pager_quit) 3063 break; 3064 } 3065 db_printf("\nMore info: show mount <addr>\n"); 3066 return; 3067 } 3068 3069 mp = (struct mount *)addr; 3070 db_printf("%p %s on %s (%s)\n", mp, mp->mnt_stat.f_mntfromname, 3071 mp->mnt_stat.f_mntonname, mp->mnt_stat.f_fstypename); 3072 3073 buf[0] = '\0'; 3074 mflags = mp->mnt_flag; 3075#define MNT_FLAG(flag) do { \ 3076 if (mflags & (flag)) { \ 3077 if (buf[0] != '\0') \ 3078 strlcat(buf, ", ", sizeof(buf)); \ 3079 strlcat(buf, (#flag) + 4, sizeof(buf)); \ 3080 mflags &= ~(flag); \ 3081 } \ 3082} while (0) 3083 MNT_FLAG(MNT_RDONLY); 3084 MNT_FLAG(MNT_SYNCHRONOUS); 3085 MNT_FLAG(MNT_NOEXEC); 3086 MNT_FLAG(MNT_NOSUID); 3087 MNT_FLAG(MNT_NFS4ACLS); 3088 MNT_FLAG(MNT_UNION); 3089 MNT_FLAG(MNT_ASYNC); 3090 MNT_FLAG(MNT_SUIDDIR); 3091 MNT_FLAG(MNT_SOFTDEP); 3092 MNT_FLAG(MNT_NOSYMFOLLOW); 3093 MNT_FLAG(MNT_GJOURNAL); 3094 MNT_FLAG(MNT_MULTILABEL); 3095 MNT_FLAG(MNT_ACLS); 3096 MNT_FLAG(MNT_NOATIME); 3097 MNT_FLAG(MNT_NOCLUSTERR); 3098 MNT_FLAG(MNT_NOCLUSTERW); 3099 MNT_FLAG(MNT_SUJ); 3100 MNT_FLAG(MNT_EXRDONLY); 3101 MNT_FLAG(MNT_EXPORTED); 3102 MNT_FLAG(MNT_DEFEXPORTED); 3103 MNT_FLAG(MNT_EXPORTANON); 3104 MNT_FLAG(MNT_EXKERB); 3105 MNT_FLAG(MNT_EXPUBLIC); 3106 MNT_FLAG(MNT_LOCAL); 3107 MNT_FLAG(MNT_QUOTA); 3108 MNT_FLAG(MNT_ROOTFS); 3109 MNT_FLAG(MNT_USER); 3110 MNT_FLAG(MNT_IGNORE); 3111 MNT_FLAG(MNT_UPDATE); 3112 MNT_FLAG(MNT_DELEXPORT); 3113 MNT_FLAG(MNT_RELOAD); 3114 MNT_FLAG(MNT_FORCE); 3115 MNT_FLAG(MNT_SNAPSHOT); 3116 MNT_FLAG(MNT_BYFSID); 3117#undef MNT_FLAG 3118 if (mflags != 0) { 3119 if (buf[0] != '\0') 3120 strlcat(buf, ", ", sizeof(buf)); 3121 snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf), 3122 "0x%016jx", mflags); 3123 } 3124 db_printf(" mnt_flag = %s\n", buf); 3125 3126 buf[0] = '\0'; 3127 flags = mp->mnt_kern_flag; 3128#define MNT_KERN_FLAG(flag) do { \ 3129 if (flags & (flag)) { \ 3130 if (buf[0] != '\0') \ 3131 strlcat(buf, ", ", sizeof(buf)); \ 3132 strlcat(buf, (#flag) + 5, sizeof(buf)); \ 3133 flags &= ~(flag); \ 3134 } \ 3135} while (0) 3136 MNT_KERN_FLAG(MNTK_UNMOUNTF); 3137 MNT_KERN_FLAG(MNTK_ASYNC); 3138 MNT_KERN_FLAG(MNTK_SOFTDEP); 3139 MNT_KERN_FLAG(MNTK_NOINSMNTQ); 3140 MNT_KERN_FLAG(MNTK_DRAINING); 3141 MNT_KERN_FLAG(MNTK_REFEXPIRE); 3142 MNT_KERN_FLAG(MNTK_EXTENDED_SHARED); 3143 MNT_KERN_FLAG(MNTK_SHARED_WRITES); 3144 MNT_KERN_FLAG(MNTK_NO_IOPF); 3145 MNT_KERN_FLAG(MNTK_VGONE_UPPER); 3146 MNT_KERN_FLAG(MNTK_VGONE_WAITER); 3147 MNT_KERN_FLAG(MNTK_LOOKUP_EXCL_DOTDOT); 3148 MNT_KERN_FLAG(MNTK_MARKER); 3149 MNT_KERN_FLAG(MNTK_USES_BCACHE); 3150 MNT_KERN_FLAG(MNTK_NOASYNC); 3151 MNT_KERN_FLAG(MNTK_UNMOUNT); 3152 MNT_KERN_FLAG(MNTK_MWAIT); 3153 MNT_KERN_FLAG(MNTK_SUSPEND); 3154 MNT_KERN_FLAG(MNTK_SUSPEND2); 3155 MNT_KERN_FLAG(MNTK_SUSPENDED); 3156 MNT_KERN_FLAG(MNTK_LOOKUP_SHARED); 3157 MNT_KERN_FLAG(MNTK_NOKNOTE); 3158#undef MNT_KERN_FLAG 3159 if (flags != 0) { 3160 if (buf[0] != '\0') 3161 strlcat(buf, ", ", sizeof(buf)); 3162 snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf), 3163 "0x%08x", flags); 3164 } 3165 db_printf(" mnt_kern_flag = %s\n", buf); 3166 3167 db_printf(" mnt_opt = "); 3168 opt = TAILQ_FIRST(mp->mnt_opt); 3169 if (opt != NULL) { 3170 db_printf("%s", opt->name); 3171 opt = TAILQ_NEXT(opt, link); 3172 while (opt != NULL) { 3173 db_printf(", %s", opt->name); 3174 opt = TAILQ_NEXT(opt, link); 3175 } 3176 } 3177 db_printf("\n"); 3178 3179 sp = &mp->mnt_stat; 3180 db_printf(" mnt_stat = { version=%u type=%u flags=0x%016jx " 3181 "bsize=%ju iosize=%ju blocks=%ju bfree=%ju bavail=%jd files=%ju " 3182 "ffree=%jd syncwrites=%ju asyncwrites=%ju syncreads=%ju " 3183 "asyncreads=%ju namemax=%u owner=%u fsid=[%d, %d] }\n", 3184 (u_int)sp->f_version, (u_int)sp->f_type, (uintmax_t)sp->f_flags, 3185 (uintmax_t)sp->f_bsize, (uintmax_t)sp->f_iosize, 3186 (uintmax_t)sp->f_blocks, (uintmax_t)sp->f_bfree, 3187 (intmax_t)sp->f_bavail, (uintmax_t)sp->f_files, 3188 (intmax_t)sp->f_ffree, (uintmax_t)sp->f_syncwrites, 3189 (uintmax_t)sp->f_asyncwrites, (uintmax_t)sp->f_syncreads, 3190 (uintmax_t)sp->f_asyncreads, (u_int)sp->f_namemax, 3191 (u_int)sp->f_owner, (int)sp->f_fsid.val[0], (int)sp->f_fsid.val[1]); 3192 3193 db_printf(" mnt_cred = { uid=%u ruid=%u", 3194 (u_int)mp->mnt_cred->cr_uid, (u_int)mp->mnt_cred->cr_ruid); 3195 if (jailed(mp->mnt_cred)) 3196 db_printf(", jail=%d", mp->mnt_cred->cr_prison->pr_id); 3197 db_printf(" }\n"); 3198 db_printf(" mnt_ref = %d\n", mp->mnt_ref); 3199 db_printf(" mnt_gen = %d\n", mp->mnt_gen); 3200 db_printf(" mnt_nvnodelistsize = %d\n", mp->mnt_nvnodelistsize); 3201 db_printf(" mnt_activevnodelistsize = %d\n", 3202 mp->mnt_activevnodelistsize); 3203 db_printf(" mnt_writeopcount = %d\n", mp->mnt_writeopcount); 3204 db_printf(" mnt_maxsymlinklen = %d\n", mp->mnt_maxsymlinklen); 3205 db_printf(" mnt_iosize_max = %d\n", mp->mnt_iosize_max); 3206 db_printf(" mnt_hashseed = %u\n", mp->mnt_hashseed); 3207 db_printf(" mnt_lockref = %d\n", mp->mnt_lockref); 3208 db_printf(" mnt_secondary_writes = %d\n", mp->mnt_secondary_writes); 3209 db_printf(" mnt_secondary_accwrites = %d\n", 3210 mp->mnt_secondary_accwrites); 3211 db_printf(" mnt_gjprovider = %s\n", 3212 mp->mnt_gjprovider != NULL ? mp->mnt_gjprovider : "NULL"); 3213 3214 db_printf("\n\nList of active vnodes\n"); 3215 TAILQ_FOREACH(vp, &mp->mnt_activevnodelist, v_actfreelist) { 3216 if (vp->v_type != VMARKER) { 3217 vn_printf(vp, "vnode "); 3218 if (db_pager_quit) 3219 break; 3220 } 3221 } 3222 db_printf("\n\nList of inactive vnodes\n"); 3223 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) { 3224 if (vp->v_type != VMARKER && (vp->v_iflag & VI_ACTIVE) == 0) { 3225 vn_printf(vp, "vnode "); 3226 if (db_pager_quit) 3227 break; 3228 } 3229 } 3230} 3231#endif /* DDB */ 3232 3233/* 3234 * Fill in a struct xvfsconf based on a struct vfsconf. 3235 */ 3236static int 3237vfsconf2x(struct sysctl_req *req, struct vfsconf *vfsp) 3238{ 3239 struct xvfsconf xvfsp; 3240 3241 bzero(&xvfsp, sizeof(xvfsp)); 3242 strcpy(xvfsp.vfc_name, vfsp->vfc_name); 3243 xvfsp.vfc_typenum = vfsp->vfc_typenum; 3244 xvfsp.vfc_refcount = vfsp->vfc_refcount; 3245 xvfsp.vfc_flags = vfsp->vfc_flags; 3246 /* 3247 * These are unused in userland, we keep them 3248 * to not break binary compatibility. 3249 */ 3250 xvfsp.vfc_vfsops = NULL; 3251 xvfsp.vfc_next = NULL; 3252 return (SYSCTL_OUT(req, &xvfsp, sizeof(xvfsp))); 3253} 3254 3255#ifdef COMPAT_FREEBSD32 3256struct xvfsconf32 { 3257 uint32_t vfc_vfsops; 3258 char vfc_name[MFSNAMELEN]; 3259 int32_t vfc_typenum; 3260 int32_t vfc_refcount; 3261 int32_t vfc_flags; 3262 uint32_t vfc_next; 3263}; 3264 3265static int 3266vfsconf2x32(struct sysctl_req *req, struct vfsconf *vfsp) 3267{ 3268 struct xvfsconf32 xvfsp; 3269 3270 strcpy(xvfsp.vfc_name, vfsp->vfc_name); 3271 xvfsp.vfc_typenum = vfsp->vfc_typenum; 3272 xvfsp.vfc_refcount = vfsp->vfc_refcount; 3273 xvfsp.vfc_flags = vfsp->vfc_flags; 3274 xvfsp.vfc_vfsops = 0; 3275 xvfsp.vfc_next = 0; 3276 return (SYSCTL_OUT(req, &xvfsp, sizeof(xvfsp))); 3277} 3278#endif 3279 3280/* 3281 * Top level filesystem related information gathering. 3282 */ 3283static int 3284sysctl_vfs_conflist(SYSCTL_HANDLER_ARGS) 3285{ 3286 struct vfsconf *vfsp; 3287 int error; 3288 3289 error = 0; 3290 vfsconf_slock(); 3291 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) { 3292#ifdef COMPAT_FREEBSD32 3293 if (req->flags & SCTL_MASK32) 3294 error = vfsconf2x32(req, vfsp); 3295 else 3296#endif 3297 error = vfsconf2x(req, vfsp); 3298 if (error) 3299 break; 3300 } 3301 vfsconf_sunlock(); 3302 return (error); 3303} 3304 3305SYSCTL_PROC(_vfs, OID_AUTO, conflist, CTLTYPE_OPAQUE | CTLFLAG_RD | 3306 CTLFLAG_MPSAFE, NULL, 0, sysctl_vfs_conflist, 3307 "S,xvfsconf", "List of all configured filesystems"); 3308 3309#ifndef BURN_BRIDGES 3310static int sysctl_ovfs_conf(SYSCTL_HANDLER_ARGS); 3311 3312static int 3313vfs_sysctl(SYSCTL_HANDLER_ARGS) 3314{ 3315 int *name = (int *)arg1 - 1; /* XXX */ 3316 u_int namelen = arg2 + 1; /* XXX */ 3317 struct vfsconf *vfsp; 3318 3319 log(LOG_WARNING, "userland calling deprecated sysctl, " 3320 "please rebuild world\n"); 3321 3322#if 1 || defined(COMPAT_PRELITE2) 3323 /* Resolve ambiguity between VFS_VFSCONF and VFS_GENERIC. */ 3324 if (namelen == 1) 3325 return (sysctl_ovfs_conf(oidp, arg1, arg2, req)); 3326#endif 3327 3328 switch (name[1]) { 3329 case VFS_MAXTYPENUM: 3330 if (namelen != 2) 3331 return (ENOTDIR); 3332 return (SYSCTL_OUT(req, &maxvfsconf, sizeof(int))); 3333 case VFS_CONF: 3334 if (namelen != 3) 3335 return (ENOTDIR); /* overloaded */ 3336 vfsconf_slock(); 3337 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) { 3338 if (vfsp->vfc_typenum == name[2]) 3339 break; 3340 } 3341 vfsconf_sunlock(); 3342 if (vfsp == NULL) 3343 return (EOPNOTSUPP); 3344#ifdef COMPAT_FREEBSD32 3345 if (req->flags & SCTL_MASK32) 3346 return (vfsconf2x32(req, vfsp)); 3347 else 3348#endif 3349 return (vfsconf2x(req, vfsp)); 3350 } 3351 return (EOPNOTSUPP); 3352} 3353 3354static SYSCTL_NODE(_vfs, VFS_GENERIC, generic, CTLFLAG_RD | CTLFLAG_SKIP | 3355 CTLFLAG_MPSAFE, vfs_sysctl, 3356 "Generic filesystem"); 3357 3358#if 1 || defined(COMPAT_PRELITE2) 3359 3360static int 3361sysctl_ovfs_conf(SYSCTL_HANDLER_ARGS) 3362{ 3363 int error; 3364 struct vfsconf *vfsp; 3365 struct ovfsconf ovfs; 3366 3367 vfsconf_slock(); 3368 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) { 3369 bzero(&ovfs, sizeof(ovfs)); 3370 ovfs.vfc_vfsops = vfsp->vfc_vfsops; /* XXX used as flag */ 3371 strcpy(ovfs.vfc_name, vfsp->vfc_name); 3372 ovfs.vfc_index = vfsp->vfc_typenum; 3373 ovfs.vfc_refcount = vfsp->vfc_refcount; 3374 ovfs.vfc_flags = vfsp->vfc_flags; 3375 error = SYSCTL_OUT(req, &ovfs, sizeof ovfs); 3376 if (error != 0) { 3377 vfsconf_sunlock(); 3378 return (error); 3379 } 3380 } 3381 vfsconf_sunlock(); 3382 return (0); 3383} 3384 3385#endif /* 1 || COMPAT_PRELITE2 */ 3386#endif /* !BURN_BRIDGES */ 3387 3388#define KINFO_VNODESLOP 10 3389#ifdef notyet 3390/* 3391 * Dump vnode list (via sysctl). 3392 */ 3393/* ARGSUSED */ 3394static int 3395sysctl_vnode(SYSCTL_HANDLER_ARGS) 3396{ 3397 struct xvnode *xvn; 3398 struct mount *mp; 3399 struct vnode *vp; 3400 int error, len, n; 3401 3402 /* 3403 * Stale numvnodes access is not fatal here. 3404 */ 3405 req->lock = 0; 3406 len = (numvnodes + KINFO_VNODESLOP) * sizeof *xvn; 3407 if (!req->oldptr) 3408 /* Make an estimate */ 3409 return (SYSCTL_OUT(req, 0, len)); 3410 3411 error = sysctl_wire_old_buffer(req, 0); 3412 if (error != 0) 3413 return (error); 3414 xvn = malloc(len, M_TEMP, M_ZERO | M_WAITOK); 3415 n = 0; 3416 mtx_lock(&mountlist_mtx); 3417 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 3418 if (vfs_busy(mp, MBF_NOWAIT | MBF_MNTLSTLOCK)) 3419 continue; 3420 MNT_ILOCK(mp); 3421 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) { 3422 if (n == len) 3423 break; 3424 vref(vp); 3425 xvn[n].xv_size = sizeof *xvn; 3426 xvn[n].xv_vnode = vp; 3427 xvn[n].xv_id = 0; /* XXX compat */ 3428#define XV_COPY(field) xvn[n].xv_##field = vp->v_##field 3429 XV_COPY(usecount); 3430 XV_COPY(writecount); 3431 XV_COPY(holdcnt); 3432 XV_COPY(mount); 3433 XV_COPY(numoutput); 3434 XV_COPY(type); 3435#undef XV_COPY 3436 xvn[n].xv_flag = vp->v_vflag; 3437 3438 switch (vp->v_type) { 3439 case VREG: 3440 case VDIR: 3441 case VLNK: 3442 break; 3443 case VBLK: 3444 case VCHR: 3445 if (vp->v_rdev == NULL) { 3446 vrele(vp); 3447 continue; 3448 } 3449 xvn[n].xv_dev = dev2udev(vp->v_rdev); 3450 break; 3451 case VSOCK: 3452 xvn[n].xv_socket = vp->v_socket; 3453 break; 3454 case VFIFO: 3455 xvn[n].xv_fifo = vp->v_fifoinfo; 3456 break; 3457 case VNON: 3458 case VBAD: 3459 default: 3460 /* shouldn't happen? */ 3461 vrele(vp); 3462 continue; 3463 } 3464 vrele(vp); 3465 ++n; 3466 } 3467 MNT_IUNLOCK(mp); 3468 mtx_lock(&mountlist_mtx); 3469 vfs_unbusy(mp); 3470 if (n == len) 3471 break; 3472 } 3473 mtx_unlock(&mountlist_mtx); 3474 3475 error = SYSCTL_OUT(req, xvn, n * sizeof *xvn); 3476 free(xvn, M_TEMP); 3477 return (error); 3478} 3479 3480SYSCTL_PROC(_kern, KERN_VNODE, vnode, CTLTYPE_OPAQUE | CTLFLAG_RD | 3481 CTLFLAG_MPSAFE, 0, 0, sysctl_vnode, "S,xvnode", 3482 ""); 3483#endif 3484 3485/* 3486 * Unmount all filesystems. The list is traversed in reverse order 3487 * of mounting to avoid dependencies. 3488 */ 3489void 3490vfs_unmountall(void) 3491{ 3492 struct mount *mp; 3493 struct thread *td; 3494 int error; 3495 3496 CTR1(KTR_VFS, "%s: unmounting all filesystems", __func__); 3497 td = curthread; 3498 3499 /* 3500 * Since this only runs when rebooting, it is not interlocked. 3501 */ 3502 while(!TAILQ_EMPTY(&mountlist)) { 3503 mp = TAILQ_LAST(&mountlist, mntlist); 3504 vfs_ref(mp); 3505 error = dounmount(mp, MNT_FORCE, td); 3506 if (error != 0) { 3507 TAILQ_REMOVE(&mountlist, mp, mnt_list); 3508 /* 3509 * XXX: Due to the way in which we mount the root 3510 * file system off of devfs, devfs will generate a 3511 * "busy" warning when we try to unmount it before 3512 * the root. Don't print a warning as a result in 3513 * order to avoid false positive errors that may 3514 * cause needless upset. 3515 */ 3516 if (strcmp(mp->mnt_vfc->vfc_name, "devfs") != 0) { 3517 printf("unmount of %s failed (", 3518 mp->mnt_stat.f_mntonname); 3519 if (error == EBUSY) 3520 printf("BUSY)\n"); 3521 else 3522 printf("%d)\n", error); 3523 } 3524 } else { 3525 /* The unmount has removed mp from the mountlist */ 3526 } 3527 } 3528} 3529 3530/* 3531 * perform msync on all vnodes under a mount point 3532 * the mount point must be locked. 3533 */ 3534void 3535vfs_msync(struct mount *mp, int flags) 3536{ 3537 struct vnode *vp, *mvp; 3538 struct vm_object *obj; 3539 3540 CTR2(KTR_VFS, "%s: mp %p", __func__, mp); 3541 MNT_VNODE_FOREACH_ACTIVE(vp, mp, mvp) { 3542 obj = vp->v_object; 3543 if (obj != NULL && (obj->flags & OBJ_MIGHTBEDIRTY) != 0 && 3544 (flags == MNT_WAIT || VOP_ISLOCKED(vp) == 0)) { 3545 if (!vget(vp, 3546 LK_EXCLUSIVE | LK_RETRY | LK_INTERLOCK, 3547 curthread)) { 3548 if (vp->v_vflag & VV_NOSYNC) { /* unlinked */ 3549 vput(vp); 3550 continue; 3551 } 3552 3553 obj = vp->v_object; 3554 if (obj != NULL) { 3555 VM_OBJECT_WLOCK(obj); 3556 vm_object_page_clean(obj, 0, 0, 3557 flags == MNT_WAIT ? 3558 OBJPC_SYNC : OBJPC_NOSYNC); 3559 VM_OBJECT_WUNLOCK(obj); 3560 } 3561 vput(vp); 3562 } 3563 } else 3564 VI_UNLOCK(vp); 3565 } 3566} 3567 3568static void 3569destroy_vpollinfo_free(struct vpollinfo *vi) 3570{ 3571 3572 knlist_destroy(&vi->vpi_selinfo.si_note); 3573 mtx_destroy(&vi->vpi_lock); 3574 uma_zfree(vnodepoll_zone, vi); 3575} 3576 3577static void 3578destroy_vpollinfo(struct vpollinfo *vi) 3579{ 3580 3581 knlist_clear(&vi->vpi_selinfo.si_note, 1); 3582 seldrain(&vi->vpi_selinfo); 3583 destroy_vpollinfo_free(vi); 3584} 3585 3586/* 3587 * Initalize per-vnode helper structure to hold poll-related state. 3588 */ 3589void 3590v_addpollinfo(struct vnode *vp) 3591{ 3592 struct vpollinfo *vi; 3593 3594 if (vp->v_pollinfo != NULL) 3595 return; 3596 vi = uma_zalloc(vnodepoll_zone, M_WAITOK); 3597 mtx_init(&vi->vpi_lock, "vnode pollinfo", NULL, MTX_DEF); 3598 knlist_init(&vi->vpi_selinfo.si_note, vp, vfs_knllock, 3599 vfs_knlunlock, vfs_knl_assert_locked, vfs_knl_assert_unlocked); 3600 VI_LOCK(vp); 3601 if (vp->v_pollinfo != NULL) { 3602 VI_UNLOCK(vp); 3603 destroy_vpollinfo_free(vi); 3604 return; 3605 } 3606 vp->v_pollinfo = vi; 3607 VI_UNLOCK(vp); 3608} 3609 3610/* 3611 * Record a process's interest in events which might happen to 3612 * a vnode. Because poll uses the historic select-style interface 3613 * internally, this routine serves as both the ``check for any 3614 * pending events'' and the ``record my interest in future events'' 3615 * functions. (These are done together, while the lock is held, 3616 * to avoid race conditions.) 3617 */ 3618int 3619vn_pollrecord(struct vnode *vp, struct thread *td, int events) 3620{ 3621 3622 v_addpollinfo(vp); 3623 mtx_lock(&vp->v_pollinfo->vpi_lock); 3624 if (vp->v_pollinfo->vpi_revents & events) { 3625 /* 3626 * This leaves events we are not interested 3627 * in available for the other process which 3628 * which presumably had requested them 3629 * (otherwise they would never have been 3630 * recorded). 3631 */ 3632 events &= vp->v_pollinfo->vpi_revents; 3633 vp->v_pollinfo->vpi_revents &= ~events; 3634 3635 mtx_unlock(&vp->v_pollinfo->vpi_lock); 3636 return (events); 3637 } 3638 vp->v_pollinfo->vpi_events |= events; 3639 selrecord(td, &vp->v_pollinfo->vpi_selinfo); 3640 mtx_unlock(&vp->v_pollinfo->vpi_lock); 3641 return (0); 3642} 3643 3644/* 3645 * Routine to create and manage a filesystem syncer vnode. 3646 */ 3647#define sync_close ((int (*)(struct vop_close_args *))nullop) 3648static int sync_fsync(struct vop_fsync_args *); 3649static int sync_inactive(struct vop_inactive_args *); 3650static int sync_reclaim(struct vop_reclaim_args *); 3651 3652static struct vop_vector sync_vnodeops = { 3653 .vop_bypass = VOP_EOPNOTSUPP, 3654 .vop_close = sync_close, /* close */ 3655 .vop_fsync = sync_fsync, /* fsync */ 3656 .vop_inactive = sync_inactive, /* inactive */ 3657 .vop_reclaim = sync_reclaim, /* reclaim */ 3658 .vop_lock1 = vop_stdlock, /* lock */ 3659 .vop_unlock = vop_stdunlock, /* unlock */ 3660 .vop_islocked = vop_stdislocked, /* islocked */ 3661}; 3662 3663/* 3664 * Create a new filesystem syncer vnode for the specified mount point. 3665 */ 3666void 3667vfs_allocate_syncvnode(struct mount *mp) 3668{ 3669 struct vnode *vp; 3670 struct bufobj *bo; 3671 static long start, incr, next; 3672 int error; 3673 3674 /* Allocate a new vnode */ 3675 error = getnewvnode("syncer", mp, &sync_vnodeops, &vp); 3676 if (error != 0) 3677 panic("vfs_allocate_syncvnode: getnewvnode() failed"); 3678 vp->v_type = VNON; 3679 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 3680 vp->v_vflag |= VV_FORCEINSMQ; 3681 error = insmntque(vp, mp); 3682 if (error != 0) 3683 panic("vfs_allocate_syncvnode: insmntque() failed"); 3684 vp->v_vflag &= ~VV_FORCEINSMQ; 3685 VOP_UNLOCK(vp, 0); 3686 /* 3687 * Place the vnode onto the syncer worklist. We attempt to 3688 * scatter them about on the list so that they will go off 3689 * at evenly distributed times even if all the filesystems 3690 * are mounted at once. 3691 */ 3692 next += incr; 3693 if (next == 0 || next > syncer_maxdelay) { 3694 start /= 2; 3695 incr /= 2; 3696 if (start == 0) { 3697 start = syncer_maxdelay / 2; 3698 incr = syncer_maxdelay; 3699 } 3700 next = start; 3701 } 3702 bo = &vp->v_bufobj; 3703 BO_LOCK(bo); 3704 vn_syncer_add_to_worklist(bo, syncdelay > 0 ? next % syncdelay : 0); 3705 /* XXX - vn_syncer_add_to_worklist() also grabs and drops sync_mtx. */ 3706 mtx_lock(&sync_mtx); 3707 sync_vnode_count++; 3708 if (mp->mnt_syncer == NULL) { 3709 mp->mnt_syncer = vp; 3710 vp = NULL; 3711 } 3712 mtx_unlock(&sync_mtx); 3713 BO_UNLOCK(bo); 3714 if (vp != NULL) { 3715 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 3716 vgone(vp); 3717 vput(vp); 3718 } 3719} 3720 3721void 3722vfs_deallocate_syncvnode(struct mount *mp) 3723{ 3724 struct vnode *vp; 3725 3726 mtx_lock(&sync_mtx); 3727 vp = mp->mnt_syncer; 3728 if (vp != NULL) 3729 mp->mnt_syncer = NULL; 3730 mtx_unlock(&sync_mtx); 3731 if (vp != NULL) 3732 vrele(vp); 3733} 3734 3735/* 3736 * Do a lazy sync of the filesystem. 3737 */ 3738static int 3739sync_fsync(struct vop_fsync_args *ap) 3740{ 3741 struct vnode *syncvp = ap->a_vp; 3742 struct mount *mp = syncvp->v_mount; 3743 int error, save; 3744 struct bufobj *bo; 3745 3746 /* 3747 * We only need to do something if this is a lazy evaluation. 3748 */ 3749 if (ap->a_waitfor != MNT_LAZY) 3750 return (0); 3751 3752 /* 3753 * Move ourselves to the back of the sync list. 3754 */ 3755 bo = &syncvp->v_bufobj; 3756 BO_LOCK(bo); 3757 vn_syncer_add_to_worklist(bo, syncdelay); 3758 BO_UNLOCK(bo); 3759 3760 /* 3761 * Walk the list of vnodes pushing all that are dirty and 3762 * not already on the sync list. 3763 */ 3764 if (vfs_busy(mp, MBF_NOWAIT) != 0) 3765 return (0); 3766 if (vn_start_write(NULL, &mp, V_NOWAIT) != 0) { 3767 vfs_unbusy(mp); 3768 return (0); 3769 } 3770 save = curthread_pflags_set(TDP_SYNCIO); 3771 vfs_msync(mp, MNT_NOWAIT); 3772 error = VFS_SYNC(mp, MNT_LAZY); 3773 curthread_pflags_restore(save); 3774 vn_finished_write(mp); 3775 vfs_unbusy(mp); 3776 return (error); 3777} 3778 3779/* 3780 * The syncer vnode is no referenced. 3781 */ 3782static int 3783sync_inactive(struct vop_inactive_args *ap) 3784{ 3785 3786 vgone(ap->a_vp); 3787 return (0); 3788} 3789 3790/* 3791 * The syncer vnode is no longer needed and is being decommissioned. 3792 * 3793 * Modifications to the worklist must be protected by sync_mtx. 3794 */ 3795static int 3796sync_reclaim(struct vop_reclaim_args *ap) 3797{ 3798 struct vnode *vp = ap->a_vp; 3799 struct bufobj *bo; 3800 3801 bo = &vp->v_bufobj; 3802 BO_LOCK(bo); 3803 mtx_lock(&sync_mtx); 3804 if (vp->v_mount->mnt_syncer == vp) 3805 vp->v_mount->mnt_syncer = NULL; 3806 if (bo->bo_flag & BO_ONWORKLST) { 3807 LIST_REMOVE(bo, bo_synclist); 3808 syncer_worklist_len--; 3809 sync_vnode_count--; 3810 bo->bo_flag &= ~BO_ONWORKLST; 3811 } 3812 mtx_unlock(&sync_mtx); 3813 BO_UNLOCK(bo); 3814 3815 return (0); 3816} 3817 3818/* 3819 * Check if vnode represents a disk device 3820 */ 3821int 3822vn_isdisk(struct vnode *vp, int *errp) 3823{ 3824 int error; 3825 3826 error = 0; 3827 dev_lock(); 3828 if (vp->v_type != VCHR) 3829 error = ENOTBLK; 3830 else if (vp->v_rdev == NULL) 3831 error = ENXIO; 3832 else if (vp->v_rdev->si_devsw == NULL) 3833 error = ENXIO; 3834 else if (!(vp->v_rdev->si_devsw->d_flags & D_DISK)) 3835 error = ENOTBLK; 3836 dev_unlock(); 3837 if (errp != NULL) 3838 *errp = error; 3839 return (error == 0); 3840} 3841 3842/* 3843 * Common filesystem object access control check routine. Accepts a 3844 * vnode's type, "mode", uid and gid, requested access mode, credentials, 3845 * and optional call-by-reference privused argument allowing vaccess() 3846 * to indicate to the caller whether privilege was used to satisfy the 3847 * request (obsoleted). Returns 0 on success, or an errno on failure. 3848 */ 3849int 3850vaccess(enum vtype type, mode_t file_mode, uid_t file_uid, gid_t file_gid, 3851 accmode_t accmode, struct ucred *cred, int *privused) 3852{ 3853 accmode_t dac_granted; 3854 accmode_t priv_granted; 3855 3856 KASSERT((accmode & ~(VEXEC | VWRITE | VREAD | VADMIN | VAPPEND)) == 0, 3857 ("invalid bit in accmode")); 3858 KASSERT((accmode & VAPPEND) == 0 || (accmode & VWRITE), 3859 ("VAPPEND without VWRITE")); 3860 3861 /* 3862 * Look for a normal, non-privileged way to access the file/directory 3863 * as requested. If it exists, go with that. 3864 */ 3865 3866 if (privused != NULL) 3867 *privused = 0; 3868 3869 dac_granted = 0; 3870 3871 /* Check the owner. */ 3872 if (cred->cr_uid == file_uid) { 3873 dac_granted |= VADMIN; 3874 if (file_mode & S_IXUSR) 3875 dac_granted |= VEXEC; 3876 if (file_mode & S_IRUSR) 3877 dac_granted |= VREAD; 3878 if (file_mode & S_IWUSR) 3879 dac_granted |= (VWRITE | VAPPEND); 3880 3881 if ((accmode & dac_granted) == accmode) 3882 return (0); 3883 3884 goto privcheck; 3885 } 3886 3887 /* Otherwise, check the groups (first match) */ 3888 if (groupmember(file_gid, cred)) { 3889 if (file_mode & S_IXGRP) 3890 dac_granted |= VEXEC; 3891 if (file_mode & S_IRGRP) 3892 dac_granted |= VREAD; 3893 if (file_mode & S_IWGRP) 3894 dac_granted |= (VWRITE | VAPPEND); 3895 3896 if ((accmode & dac_granted) == accmode) 3897 return (0); 3898 3899 goto privcheck; 3900 } 3901 3902 /* Otherwise, check everyone else. */ 3903 if (file_mode & S_IXOTH) 3904 dac_granted |= VEXEC; 3905 if (file_mode & S_IROTH) 3906 dac_granted |= VREAD; 3907 if (file_mode & S_IWOTH) 3908 dac_granted |= (VWRITE | VAPPEND); 3909 if ((accmode & dac_granted) == accmode) 3910 return (0); 3911 3912privcheck: 3913 /* 3914 * Build a privilege mask to determine if the set of privileges 3915 * satisfies the requirements when combined with the granted mask 3916 * from above. For each privilege, if the privilege is required, 3917 * bitwise or the request type onto the priv_granted mask. 3918 */ 3919 priv_granted = 0; 3920 3921 if (type == VDIR) { 3922 /* 3923 * For directories, use PRIV_VFS_LOOKUP to satisfy VEXEC 3924 * requests, instead of PRIV_VFS_EXEC. 3925 */ 3926 if ((accmode & VEXEC) && ((dac_granted & VEXEC) == 0) && 3927 !priv_check_cred(cred, PRIV_VFS_LOOKUP, 0)) 3928 priv_granted |= VEXEC; 3929 } else { 3930 /* 3931 * Ensure that at least one execute bit is on. Otherwise, 3932 * a privileged user will always succeed, and we don't want 3933 * this to happen unless the file really is executable. 3934 */ 3935 if ((accmode & VEXEC) && ((dac_granted & VEXEC) == 0) && 3936 (file_mode & (S_IXUSR | S_IXGRP | S_IXOTH)) != 0 && 3937 !priv_check_cred(cred, PRIV_VFS_EXEC, 0)) 3938 priv_granted |= VEXEC; 3939 } 3940 3941 if ((accmode & VREAD) && ((dac_granted & VREAD) == 0) && 3942 !priv_check_cred(cred, PRIV_VFS_READ, 0)) 3943 priv_granted |= VREAD; 3944 3945 if ((accmode & VWRITE) && ((dac_granted & VWRITE) == 0) && 3946 !priv_check_cred(cred, PRIV_VFS_WRITE, 0)) 3947 priv_granted |= (VWRITE | VAPPEND); 3948 3949 if ((accmode & VADMIN) && ((dac_granted & VADMIN) == 0) && 3950 !priv_check_cred(cred, PRIV_VFS_ADMIN, 0)) 3951 priv_granted |= VADMIN; 3952 3953 if ((accmode & (priv_granted | dac_granted)) == accmode) { 3954 /* XXX audit: privilege used */ 3955 if (privused != NULL) 3956 *privused = 1; 3957 return (0); 3958 } 3959 3960 return ((accmode & VADMIN) ? EPERM : EACCES); 3961} 3962 3963/* 3964 * Credential check based on process requesting service, and per-attribute 3965 * permissions. 3966 */ 3967int 3968extattr_check_cred(struct vnode *vp, int attrnamespace, struct ucred *cred, 3969 struct thread *td, accmode_t accmode) 3970{ 3971 3972 /* 3973 * Kernel-invoked always succeeds. 3974 */ 3975 if (cred == NOCRED) 3976 return (0); 3977 3978 /* 3979 * Do not allow privileged processes in jail to directly manipulate 3980 * system attributes. 3981 */ 3982 switch (attrnamespace) { 3983 case EXTATTR_NAMESPACE_SYSTEM: 3984 /* Potentially should be: return (EPERM); */ 3985 return (priv_check_cred(cred, PRIV_VFS_EXTATTR_SYSTEM, 0)); 3986 case EXTATTR_NAMESPACE_USER: 3987 return (VOP_ACCESS(vp, accmode, cred, td)); 3988 default: 3989 return (EPERM); 3990 } 3991} 3992 3993#ifdef DEBUG_VFS_LOCKS 3994/* 3995 * This only exists to supress warnings from unlocked specfs accesses. It is 3996 * no longer ok to have an unlocked VFS. 3997 */ 3998#define IGNORE_LOCK(vp) (panicstr != NULL || (vp) == NULL || \ 3999 (vp)->v_type == VCHR || (vp)->v_type == VBAD) 4000 4001int vfs_badlock_ddb = 1; /* Drop into debugger on violation. */ 4002SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_ddb, CTLFLAG_RW, &vfs_badlock_ddb, 0, 4003 "Drop into debugger on lock violation"); 4004 4005int vfs_badlock_mutex = 1; /* Check for interlock across VOPs. */ 4006SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_mutex, CTLFLAG_RW, &vfs_badlock_mutex, 4007 0, "Check for interlock across VOPs"); 4008 4009int vfs_badlock_print = 1; /* Print lock violations. */ 4010SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_print, CTLFLAG_RW, &vfs_badlock_print, 4011 0, "Print lock violations"); 4012 4013#ifdef KDB 4014int vfs_badlock_backtrace = 1; /* Print backtrace at lock violations. */ 4015SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_backtrace, CTLFLAG_RW, 4016 &vfs_badlock_backtrace, 0, "Print backtrace at lock violations"); 4017#endif 4018 4019static void 4020vfs_badlock(const char *msg, const char *str, struct vnode *vp) 4021{ 4022 4023#ifdef KDB 4024 if (vfs_badlock_backtrace) 4025 kdb_backtrace(); 4026#endif 4027 if (vfs_badlock_print) 4028 printf("%s: %p %s\n", str, (void *)vp, msg); 4029 if (vfs_badlock_ddb) 4030 kdb_enter(KDB_WHY_VFSLOCK, "lock violation"); 4031} 4032 4033void 4034assert_vi_locked(struct vnode *vp, const char *str) 4035{ 4036 4037 if (vfs_badlock_mutex && !mtx_owned(VI_MTX(vp))) 4038 vfs_badlock("interlock is not locked but should be", str, vp); 4039} 4040 4041void 4042assert_vi_unlocked(struct vnode *vp, const char *str) 4043{ 4044 4045 if (vfs_badlock_mutex && mtx_owned(VI_MTX(vp))) 4046 vfs_badlock("interlock is locked but should not be", str, vp); 4047} 4048 4049void 4050assert_vop_locked(struct vnode *vp, const char *str) 4051{ 4052 int locked; 4053 4054 if (!IGNORE_LOCK(vp)) { 4055 locked = VOP_ISLOCKED(vp); 4056 if (locked == 0 || locked == LK_EXCLOTHER) 4057 vfs_badlock("is not locked but should be", str, vp); 4058 } 4059} 4060 4061void 4062assert_vop_unlocked(struct vnode *vp, const char *str) 4063{ 4064 4065 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) == LK_EXCLUSIVE) 4066 vfs_badlock("is locked but should not be", str, vp); 4067} 4068 4069void 4070assert_vop_elocked(struct vnode *vp, const char *str) 4071{ 4072 4073 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) != LK_EXCLUSIVE) 4074 vfs_badlock("is not exclusive locked but should be", str, vp); 4075} 4076 4077#if 0 4078void 4079assert_vop_elocked_other(struct vnode *vp, const char *str) 4080{ 4081 4082 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) != LK_EXCLOTHER) 4083 vfs_badlock("is not exclusive locked by another thread", 4084 str, vp); 4085} 4086 4087void 4088assert_vop_slocked(struct vnode *vp, const char *str) 4089{ 4090 4091 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) != LK_SHARED) 4092 vfs_badlock("is not locked shared but should be", str, vp); 4093} 4094#endif /* 0 */ 4095#endif /* DEBUG_VFS_LOCKS */ 4096 4097void 4098vop_rename_fail(struct vop_rename_args *ap) 4099{ 4100 4101 if (ap->a_tvp != NULL) 4102 vput(ap->a_tvp); 4103 if (ap->a_tdvp == ap->a_tvp) 4104 vrele(ap->a_tdvp); 4105 else 4106 vput(ap->a_tdvp); 4107 vrele(ap->a_fdvp); 4108 vrele(ap->a_fvp); 4109} 4110 4111void 4112vop_rename_pre(void *ap) 4113{ 4114 struct vop_rename_args *a = ap; 4115 4116#ifdef DEBUG_VFS_LOCKS 4117 if (a->a_tvp) 4118 ASSERT_VI_UNLOCKED(a->a_tvp, "VOP_RENAME"); 4119 ASSERT_VI_UNLOCKED(a->a_tdvp, "VOP_RENAME"); 4120 ASSERT_VI_UNLOCKED(a->a_fvp, "VOP_RENAME"); 4121 ASSERT_VI_UNLOCKED(a->a_fdvp, "VOP_RENAME"); 4122 4123 /* Check the source (from). */ 4124 if (a->a_tdvp->v_vnlock != a->a_fdvp->v_vnlock && 4125 (a->a_tvp == NULL || a->a_tvp->v_vnlock != a->a_fdvp->v_vnlock)) 4126 ASSERT_VOP_UNLOCKED(a->a_fdvp, "vop_rename: fdvp locked"); 4127 if (a->a_tvp == NULL || a->a_tvp->v_vnlock != a->a_fvp->v_vnlock) 4128 ASSERT_VOP_UNLOCKED(a->a_fvp, "vop_rename: fvp locked"); 4129 4130 /* Check the target. */ 4131 if (a->a_tvp) 4132 ASSERT_VOP_LOCKED(a->a_tvp, "vop_rename: tvp not locked"); 4133 ASSERT_VOP_LOCKED(a->a_tdvp, "vop_rename: tdvp not locked"); 4134#endif 4135 if (a->a_tdvp != a->a_fdvp) 4136 vhold(a->a_fdvp); 4137 if (a->a_tvp != a->a_fvp) 4138 vhold(a->a_fvp); 4139 vhold(a->a_tdvp); 4140 if (a->a_tvp) 4141 vhold(a->a_tvp); 4142} 4143 4144void 4145vop_strategy_pre(void *ap) 4146{ 4147#ifdef DEBUG_VFS_LOCKS 4148 struct vop_strategy_args *a; 4149 struct buf *bp; 4150 4151 a = ap; 4152 bp = a->a_bp; 4153 4154 /* 4155 * Cluster ops lock their component buffers but not the IO container. 4156 */ 4157 if ((bp->b_flags & B_CLUSTER) != 0) 4158 return; 4159 4160 if (panicstr == NULL && !BUF_ISLOCKED(bp)) { 4161 if (vfs_badlock_print) 4162 printf( 4163 "VOP_STRATEGY: bp is not locked but should be\n"); 4164 if (vfs_badlock_ddb) 4165 kdb_enter(KDB_WHY_VFSLOCK, "lock violation"); 4166 } 4167#endif 4168} 4169 4170void 4171vop_lock_pre(void *ap) 4172{ 4173#ifdef DEBUG_VFS_LOCKS 4174 struct vop_lock1_args *a = ap; 4175 4176 if ((a->a_flags & LK_INTERLOCK) == 0) 4177 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_LOCK"); 4178 else 4179 ASSERT_VI_LOCKED(a->a_vp, "VOP_LOCK"); 4180#endif 4181} 4182 4183void 4184vop_lock_post(void *ap, int rc) 4185{ 4186#ifdef DEBUG_VFS_LOCKS 4187 struct vop_lock1_args *a = ap; 4188 4189 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_LOCK"); 4190 if (rc == 0 && (a->a_flags & LK_EXCLOTHER) == 0) 4191 ASSERT_VOP_LOCKED(a->a_vp, "VOP_LOCK"); 4192#endif 4193} 4194 4195void 4196vop_unlock_pre(void *ap) 4197{ 4198#ifdef DEBUG_VFS_LOCKS 4199 struct vop_unlock_args *a = ap; 4200 4201 if (a->a_flags & LK_INTERLOCK) 4202 ASSERT_VI_LOCKED(a->a_vp, "VOP_UNLOCK"); 4203 ASSERT_VOP_LOCKED(a->a_vp, "VOP_UNLOCK"); 4204#endif 4205} 4206 4207void 4208vop_unlock_post(void *ap, int rc) 4209{ 4210#ifdef DEBUG_VFS_LOCKS 4211 struct vop_unlock_args *a = ap; 4212 4213 if (a->a_flags & LK_INTERLOCK) 4214 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_UNLOCK"); 4215#endif 4216} 4217 4218void 4219vop_create_post(void *ap, int rc) 4220{ 4221 struct vop_create_args *a = ap; 4222 4223 if (!rc) 4224 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 4225} 4226 4227void 4228vop_deleteextattr_post(void *ap, int rc) 4229{ 4230 struct vop_deleteextattr_args *a = ap; 4231 4232 if (!rc) 4233 VFS_KNOTE_LOCKED(a->a_vp, NOTE_ATTRIB); 4234} 4235 4236void 4237vop_link_post(void *ap, int rc) 4238{ 4239 struct vop_link_args *a = ap; 4240 4241 if (!rc) { 4242 VFS_KNOTE_LOCKED(a->a_vp, NOTE_LINK); 4243 VFS_KNOTE_LOCKED(a->a_tdvp, NOTE_WRITE); 4244 } 4245} 4246 4247void 4248vop_mkdir_post(void *ap, int rc) 4249{ 4250 struct vop_mkdir_args *a = ap; 4251 4252 if (!rc) 4253 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE | NOTE_LINK); 4254} 4255 4256void 4257vop_mknod_post(void *ap, int rc) 4258{ 4259 struct vop_mknod_args *a = ap; 4260 4261 if (!rc) 4262 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 4263} 4264 4265void 4266vop_remove_post(void *ap, int rc) 4267{ 4268 struct vop_remove_args *a = ap; 4269 4270 if (!rc) { 4271 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 4272 VFS_KNOTE_LOCKED(a->a_vp, NOTE_DELETE); 4273 } 4274} 4275 4276void 4277vop_rename_post(void *ap, int rc) 4278{ 4279 struct vop_rename_args *a = ap; 4280 4281 if (!rc) { 4282 VFS_KNOTE_UNLOCKED(a->a_fdvp, NOTE_WRITE); 4283 VFS_KNOTE_UNLOCKED(a->a_tdvp, NOTE_WRITE); 4284 VFS_KNOTE_UNLOCKED(a->a_fvp, NOTE_RENAME); 4285 if (a->a_tvp) 4286 VFS_KNOTE_UNLOCKED(a->a_tvp, NOTE_DELETE); 4287 } 4288 if (a->a_tdvp != a->a_fdvp) 4289 vdrop(a->a_fdvp); 4290 if (a->a_tvp != a->a_fvp) 4291 vdrop(a->a_fvp); 4292 vdrop(a->a_tdvp); 4293 if (a->a_tvp) 4294 vdrop(a->a_tvp); 4295} 4296 4297void 4298vop_rmdir_post(void *ap, int rc) 4299{ 4300 struct vop_rmdir_args *a = ap; 4301 4302 if (!rc) { 4303 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE | NOTE_LINK); 4304 VFS_KNOTE_LOCKED(a->a_vp, NOTE_DELETE); 4305 } 4306} 4307 4308void 4309vop_setattr_post(void *ap, int rc) 4310{ 4311 struct vop_setattr_args *a = ap; 4312 4313 if (!rc) 4314 VFS_KNOTE_LOCKED(a->a_vp, NOTE_ATTRIB); 4315} 4316 4317void 4318vop_setextattr_post(void *ap, int rc) 4319{ 4320 struct vop_setextattr_args *a = ap; 4321 4322 if (!rc) 4323 VFS_KNOTE_LOCKED(a->a_vp, NOTE_ATTRIB); 4324} 4325 4326void 4327vop_symlink_post(void *ap, int rc) 4328{ 4329 struct vop_symlink_args *a = ap; 4330 4331 if (!rc) 4332 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 4333} 4334 4335static struct knlist fs_knlist; 4336 4337static void 4338vfs_event_init(void *arg) 4339{ 4340 knlist_init_mtx(&fs_knlist, NULL); 4341} 4342/* XXX - correct order? */ 4343SYSINIT(vfs_knlist, SI_SUB_VFS, SI_ORDER_ANY, vfs_event_init, NULL); 4344 4345void 4346vfs_event_signal(fsid_t *fsid, uint32_t event, intptr_t data __unused) 4347{ 4348 4349 KNOTE_UNLOCKED(&fs_knlist, event); 4350} 4351 4352static int filt_fsattach(struct knote *kn); 4353static void filt_fsdetach(struct knote *kn); 4354static int filt_fsevent(struct knote *kn, long hint); 4355 4356struct filterops fs_filtops = { 4357 .f_isfd = 0, 4358 .f_attach = filt_fsattach, 4359 .f_detach = filt_fsdetach, 4360 .f_event = filt_fsevent 4361}; 4362 4363static int 4364filt_fsattach(struct knote *kn) 4365{ 4366 4367 kn->kn_flags |= EV_CLEAR; 4368 knlist_add(&fs_knlist, kn, 0); 4369 return (0); 4370} 4371 4372static void 4373filt_fsdetach(struct knote *kn) 4374{ 4375 4376 knlist_remove(&fs_knlist, kn, 0); 4377} 4378 4379static int 4380filt_fsevent(struct knote *kn, long hint) 4381{ 4382 4383 kn->kn_fflags |= hint; 4384 return (kn->kn_fflags != 0); 4385} 4386 4387static int 4388sysctl_vfs_ctl(SYSCTL_HANDLER_ARGS) 4389{ 4390 struct vfsidctl vc; 4391 int error; 4392 struct mount *mp; 4393 4394 error = SYSCTL_IN(req, &vc, sizeof(vc)); 4395 if (error) 4396 return (error); 4397 if (vc.vc_vers != VFS_CTL_VERS1) 4398 return (EINVAL); 4399 mp = vfs_getvfs(&vc.vc_fsid); 4400 if (mp == NULL) 4401 return (ENOENT); 4402 /* ensure that a specific sysctl goes to the right filesystem. */ 4403 if (strcmp(vc.vc_fstypename, "*") != 0 && 4404 strcmp(vc.vc_fstypename, mp->mnt_vfc->vfc_name) != 0) { 4405 vfs_rel(mp); 4406 return (EINVAL); 4407 } 4408 VCTLTOREQ(&vc, req); 4409 error = VFS_SYSCTL(mp, vc.vc_op, req); 4410 vfs_rel(mp); 4411 return (error); 4412} 4413 4414SYSCTL_PROC(_vfs, OID_AUTO, ctl, CTLTYPE_OPAQUE | CTLFLAG_WR, 4415 NULL, 0, sysctl_vfs_ctl, "", 4416 "Sysctl by fsid"); 4417 4418/* 4419 * Function to initialize a va_filerev field sensibly. 4420 * XXX: Wouldn't a random number make a lot more sense ?? 4421 */ 4422u_quad_t 4423init_va_filerev(void) 4424{ 4425 struct bintime bt; 4426 4427 getbinuptime(&bt); 4428 return (((u_quad_t)bt.sec << 32LL) | (bt.frac >> 32LL)); 4429} 4430 4431static int filt_vfsread(struct knote *kn, long hint); 4432static int filt_vfswrite(struct knote *kn, long hint); 4433static int filt_vfsvnode(struct knote *kn, long hint); 4434static void filt_vfsdetach(struct knote *kn); 4435static struct filterops vfsread_filtops = { 4436 .f_isfd = 1, 4437 .f_detach = filt_vfsdetach, 4438 .f_event = filt_vfsread 4439}; 4440static struct filterops vfswrite_filtops = { 4441 .f_isfd = 1, 4442 .f_detach = filt_vfsdetach, 4443 .f_event = filt_vfswrite 4444}; 4445static struct filterops vfsvnode_filtops = { 4446 .f_isfd = 1, 4447 .f_detach = filt_vfsdetach, 4448 .f_event = filt_vfsvnode 4449}; 4450 4451static void 4452vfs_knllock(void *arg) 4453{ 4454 struct vnode *vp = arg; 4455 4456 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 4457} 4458 4459static void 4460vfs_knlunlock(void *arg) 4461{ 4462 struct vnode *vp = arg; 4463 4464 VOP_UNLOCK(vp, 0); 4465} 4466 4467static void 4468vfs_knl_assert_locked(void *arg) 4469{ 4470#ifdef DEBUG_VFS_LOCKS 4471 struct vnode *vp = arg; 4472 4473 ASSERT_VOP_LOCKED(vp, "vfs_knl_assert_locked"); 4474#endif 4475} 4476 4477static void 4478vfs_knl_assert_unlocked(void *arg) 4479{ 4480#ifdef DEBUG_VFS_LOCKS 4481 struct vnode *vp = arg; 4482 4483 ASSERT_VOP_UNLOCKED(vp, "vfs_knl_assert_unlocked"); 4484#endif 4485} 4486 4487int 4488vfs_kqfilter(struct vop_kqfilter_args *ap) 4489{ 4490 struct vnode *vp = ap->a_vp; 4491 struct knote *kn = ap->a_kn; 4492 struct knlist *knl; 4493 4494 switch (kn->kn_filter) { 4495 case EVFILT_READ: 4496 kn->kn_fop = &vfsread_filtops; 4497 break; 4498 case EVFILT_WRITE: 4499 kn->kn_fop = &vfswrite_filtops; 4500 break; 4501 case EVFILT_VNODE: 4502 kn->kn_fop = &vfsvnode_filtops; 4503 break; 4504 default: 4505 return (EINVAL); 4506 } 4507 4508 kn->kn_hook = (caddr_t)vp; 4509 4510 v_addpollinfo(vp); 4511 if (vp->v_pollinfo == NULL) 4512 return (ENOMEM); 4513 knl = &vp->v_pollinfo->vpi_selinfo.si_note; 4514 vhold(vp); 4515 knlist_add(knl, kn, 0); 4516 4517 return (0); 4518} 4519 4520/* 4521 * Detach knote from vnode 4522 */ 4523static void 4524filt_vfsdetach(struct knote *kn) 4525{ 4526 struct vnode *vp = (struct vnode *)kn->kn_hook; 4527 4528 KASSERT(vp->v_pollinfo != NULL, ("Missing v_pollinfo")); 4529 knlist_remove(&vp->v_pollinfo->vpi_selinfo.si_note, kn, 0); 4530 vdrop(vp); 4531} 4532 4533/*ARGSUSED*/ 4534static int 4535filt_vfsread(struct knote *kn, long hint) 4536{ 4537 struct vnode *vp = (struct vnode *)kn->kn_hook; 4538 struct vattr va; 4539 int res; 4540 4541 /* 4542 * filesystem is gone, so set the EOF flag and schedule 4543 * the knote for deletion. 4544 */ 4545 if (hint == NOTE_REVOKE) { 4546 VI_LOCK(vp); 4547 kn->kn_flags |= (EV_EOF | EV_ONESHOT); 4548 VI_UNLOCK(vp); 4549 return (1); 4550 } 4551 4552 if (VOP_GETATTR(vp, &va, curthread->td_ucred)) 4553 return (0); 4554 4555 VI_LOCK(vp); 4556 kn->kn_data = va.va_size - kn->kn_fp->f_offset; 4557 res = (kn->kn_data != 0); 4558 VI_UNLOCK(vp); 4559 return (res); 4560} 4561 4562/*ARGSUSED*/ 4563static int 4564filt_vfswrite(struct knote *kn, long hint) 4565{ 4566 struct vnode *vp = (struct vnode *)kn->kn_hook; 4567 4568 VI_LOCK(vp); 4569 4570 /* 4571 * filesystem is gone, so set the EOF flag and schedule 4572 * the knote for deletion. 4573 */ 4574 if (hint == NOTE_REVOKE) 4575 kn->kn_flags |= (EV_EOF | EV_ONESHOT); 4576 4577 kn->kn_data = 0; 4578 VI_UNLOCK(vp); 4579 return (1); 4580} 4581 4582static int 4583filt_vfsvnode(struct knote *kn, long hint) 4584{ 4585 struct vnode *vp = (struct vnode *)kn->kn_hook; 4586 int res; 4587 4588 VI_LOCK(vp); 4589 if (kn->kn_sfflags & hint) 4590 kn->kn_fflags |= hint; 4591 if (hint == NOTE_REVOKE) { 4592 kn->kn_flags |= EV_EOF; 4593 VI_UNLOCK(vp); 4594 return (1); 4595 } 4596 res = (kn->kn_fflags != 0); 4597 VI_UNLOCK(vp); 4598 return (res); 4599} 4600 4601int 4602vfs_read_dirent(struct vop_readdir_args *ap, struct dirent *dp, off_t off) 4603{ 4604 int error; 4605 4606 if (dp->d_reclen > ap->a_uio->uio_resid) 4607 return (ENAMETOOLONG); 4608 error = uiomove(dp, dp->d_reclen, ap->a_uio); 4609 if (error) { 4610 if (ap->a_ncookies != NULL) { 4611 if (ap->a_cookies != NULL) 4612 free(ap->a_cookies, M_TEMP); 4613 ap->a_cookies = NULL; 4614 *ap->a_ncookies = 0; 4615 } 4616 return (error); 4617 } 4618 if (ap->a_ncookies == NULL) 4619 return (0); 4620 4621 KASSERT(ap->a_cookies, 4622 ("NULL ap->a_cookies value with non-NULL ap->a_ncookies!")); 4623 4624 *ap->a_cookies = realloc(*ap->a_cookies, 4625 (*ap->a_ncookies + 1) * sizeof(u_long), M_TEMP, M_WAITOK | M_ZERO); 4626 (*ap->a_cookies)[*ap->a_ncookies] = off; 4627 return (0); 4628} 4629 4630/* 4631 * Mark for update the access time of the file if the filesystem 4632 * supports VOP_MARKATIME. This functionality is used by execve and 4633 * mmap, so we want to avoid the I/O implied by directly setting 4634 * va_atime for the sake of efficiency. 4635 */ 4636void 4637vfs_mark_atime(struct vnode *vp, struct ucred *cred) 4638{ 4639 struct mount *mp; 4640 4641 mp = vp->v_mount; 4642 ASSERT_VOP_LOCKED(vp, "vfs_mark_atime"); 4643 if (mp != NULL && (mp->mnt_flag & (MNT_NOATIME | MNT_RDONLY)) == 0) 4644 (void)VOP_MARKATIME(vp); 4645} 4646 4647/* 4648 * The purpose of this routine is to remove granularity from accmode_t, 4649 * reducing it into standard unix access bits - VEXEC, VREAD, VWRITE, 4650 * VADMIN and VAPPEND. 4651 * 4652 * If it returns 0, the caller is supposed to continue with the usual 4653 * access checks using 'accmode' as modified by this routine. If it 4654 * returns nonzero value, the caller is supposed to return that value 4655 * as errno. 4656 * 4657 * Note that after this routine runs, accmode may be zero. 4658 */ 4659int 4660vfs_unixify_accmode(accmode_t *accmode) 4661{ 4662 /* 4663 * There is no way to specify explicit "deny" rule using 4664 * file mode or POSIX.1e ACLs. 4665 */ 4666 if (*accmode & VEXPLICIT_DENY) { 4667 *accmode = 0; 4668 return (0); 4669 } 4670 4671 /* 4672 * None of these can be translated into usual access bits. 4673 * Also, the common case for NFSv4 ACLs is to not contain 4674 * either of these bits. Caller should check for VWRITE 4675 * on the containing directory instead. 4676 */ 4677 if (*accmode & (VDELETE_CHILD | VDELETE)) 4678 return (EPERM); 4679 4680 if (*accmode & VADMIN_PERMS) { 4681 *accmode &= ~VADMIN_PERMS; 4682 *accmode |= VADMIN; 4683 } 4684 4685 /* 4686 * There is no way to deny VREAD_ATTRIBUTES, VREAD_ACL 4687 * or VSYNCHRONIZE using file mode or POSIX.1e ACL. 4688 */ 4689 *accmode &= ~(VSTAT_PERMS | VSYNCHRONIZE); 4690 4691 return (0); 4692} 4693 4694/* 4695 * These are helper functions for filesystems to traverse all 4696 * their vnodes. See MNT_VNODE_FOREACH_ALL() in sys/mount.h. 4697 * 4698 * This interface replaces MNT_VNODE_FOREACH. 4699 */ 4700 4701MALLOC_DEFINE(M_VNODE_MARKER, "vnodemarker", "vnode marker"); 4702 4703struct vnode * 4704__mnt_vnode_next_all(struct vnode **mvp, struct mount *mp) 4705{ 4706 struct vnode *vp; 4707 4708 if (should_yield()) 4709 kern_yield(PRI_USER); 4710 MNT_ILOCK(mp); 4711 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch")); 4712 vp = TAILQ_NEXT(*mvp, v_nmntvnodes); 4713 while (vp != NULL && (vp->v_type == VMARKER || 4714 (vp->v_iflag & VI_DOOMED) != 0)) 4715 vp = TAILQ_NEXT(vp, v_nmntvnodes); 4716 4717 /* Check if we are done */ 4718 if (vp == NULL) { 4719 __mnt_vnode_markerfree_all(mvp, mp); 4720 /* MNT_IUNLOCK(mp); -- done in above function */ 4721 mtx_assert(MNT_MTX(mp), MA_NOTOWNED); 4722 return (NULL); 4723 } 4724 TAILQ_REMOVE(&mp->mnt_nvnodelist, *mvp, v_nmntvnodes); 4725 TAILQ_INSERT_AFTER(&mp->mnt_nvnodelist, vp, *mvp, v_nmntvnodes); 4726 VI_LOCK(vp); 4727 MNT_IUNLOCK(mp); 4728 return (vp); 4729} 4730 4731struct vnode * 4732__mnt_vnode_first_all(struct vnode **mvp, struct mount *mp) 4733{ 4734 struct vnode *vp; 4735 4736 *mvp = malloc(sizeof(struct vnode), M_VNODE_MARKER, M_WAITOK | M_ZERO); 4737 MNT_ILOCK(mp); 4738 MNT_REF(mp); 4739 (*mvp)->v_type = VMARKER; 4740 4741 vp = TAILQ_FIRST(&mp->mnt_nvnodelist); 4742 while (vp != NULL && (vp->v_type == VMARKER || 4743 (vp->v_iflag & VI_DOOMED) != 0)) 4744 vp = TAILQ_NEXT(vp, v_nmntvnodes); 4745 4746 /* Check if we are done */ 4747 if (vp == NULL) { 4748 MNT_REL(mp); 4749 MNT_IUNLOCK(mp); 4750 free(*mvp, M_VNODE_MARKER); 4751 *mvp = NULL; 4752 return (NULL); 4753 } 4754 (*mvp)->v_mount = mp; 4755 TAILQ_INSERT_AFTER(&mp->mnt_nvnodelist, vp, *mvp, v_nmntvnodes); 4756 VI_LOCK(vp); 4757 MNT_IUNLOCK(mp); 4758 return (vp); 4759} 4760 4761 4762void 4763__mnt_vnode_markerfree_all(struct vnode **mvp, struct mount *mp) 4764{ 4765 4766 if (*mvp == NULL) { 4767 MNT_IUNLOCK(mp); 4768 return; 4769 } 4770 4771 mtx_assert(MNT_MTX(mp), MA_OWNED); 4772 4773 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch")); 4774 TAILQ_REMOVE(&mp->mnt_nvnodelist, *mvp, v_nmntvnodes); 4775 MNT_REL(mp); 4776 MNT_IUNLOCK(mp); 4777 free(*mvp, M_VNODE_MARKER); 4778 *mvp = NULL; 4779} 4780 4781/* 4782 * These are helper functions for filesystems to traverse their 4783 * active vnodes. See MNT_VNODE_FOREACH_ACTIVE() in sys/mount.h 4784 */ 4785static void 4786mnt_vnode_markerfree_active(struct vnode **mvp, struct mount *mp) 4787{ 4788 4789 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch")); 4790 4791 MNT_ILOCK(mp); 4792 MNT_REL(mp); 4793 MNT_IUNLOCK(mp); 4794 free(*mvp, M_VNODE_MARKER); 4795 *mvp = NULL; 4796} 4797 4798static struct vnode * 4799mnt_vnode_next_active(struct vnode **mvp, struct mount *mp) 4800{ 4801 struct vnode *vp, *nvp; 4802 4803 mtx_assert(&vnode_free_list_mtx, MA_OWNED); 4804 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch")); 4805restart: 4806 vp = TAILQ_NEXT(*mvp, v_actfreelist); 4807 TAILQ_REMOVE(&mp->mnt_activevnodelist, *mvp, v_actfreelist); 4808 while (vp != NULL) { 4809 if (vp->v_type == VMARKER) { 4810 vp = TAILQ_NEXT(vp, v_actfreelist); 4811 continue; 4812 } 4813 if (!VI_TRYLOCK(vp)) { 4814 if (mp_ncpus == 1 || should_yield()) { 4815 TAILQ_INSERT_BEFORE(vp, *mvp, v_actfreelist); 4816 mtx_unlock(&vnode_free_list_mtx); 4817 pause("vnacti", 1); 4818 mtx_lock(&vnode_free_list_mtx); 4819 goto restart; 4820 } 4821 continue; 4822 } 4823 KASSERT(vp->v_type != VMARKER, ("locked marker %p", vp)); 4824 KASSERT(vp->v_mount == mp || vp->v_mount == NULL, 4825 ("alien vnode on the active list %p %p", vp, mp)); 4826 if (vp->v_mount == mp && (vp->v_iflag & VI_DOOMED) == 0) 4827 break; 4828 nvp = TAILQ_NEXT(vp, v_actfreelist); 4829 VI_UNLOCK(vp); 4830 vp = nvp; 4831 } 4832 4833 /* Check if we are done */ 4834 if (vp == NULL) { 4835 mtx_unlock(&vnode_free_list_mtx); 4836 mnt_vnode_markerfree_active(mvp, mp); 4837 return (NULL); 4838 } 4839 TAILQ_INSERT_AFTER(&mp->mnt_activevnodelist, vp, *mvp, v_actfreelist); 4840 mtx_unlock(&vnode_free_list_mtx); 4841 ASSERT_VI_LOCKED(vp, "active iter"); 4842 KASSERT((vp->v_iflag & VI_ACTIVE) != 0, ("Non-active vp %p", vp)); 4843 return (vp); 4844} 4845 4846struct vnode * 4847__mnt_vnode_next_active(struct vnode **mvp, struct mount *mp) 4848{ 4849 4850 if (should_yield()) 4851 kern_yield(PRI_USER); 4852 mtx_lock(&vnode_free_list_mtx); 4853 return (mnt_vnode_next_active(mvp, mp)); 4854} 4855 4856struct vnode * 4857__mnt_vnode_first_active(struct vnode **mvp, struct mount *mp) 4858{ 4859 struct vnode *vp; 4860 4861 *mvp = malloc(sizeof(struct vnode), M_VNODE_MARKER, M_WAITOK | M_ZERO); 4862 MNT_ILOCK(mp); 4863 MNT_REF(mp); 4864 MNT_IUNLOCK(mp); 4865 (*mvp)->v_type = VMARKER; 4866 (*mvp)->v_mount = mp; 4867 4868 mtx_lock(&vnode_free_list_mtx); 4869 vp = TAILQ_FIRST(&mp->mnt_activevnodelist); 4870 if (vp == NULL) { 4871 mtx_unlock(&vnode_free_list_mtx); 4872 mnt_vnode_markerfree_active(mvp, mp); 4873 return (NULL); 4874 } 4875 TAILQ_INSERT_BEFORE(vp, *mvp, v_actfreelist); 4876 return (mnt_vnode_next_active(mvp, mp)); 4877} 4878 4879void 4880__mnt_vnode_markerfree_active(struct vnode **mvp, struct mount *mp) 4881{ 4882 4883 if (*mvp == NULL) 4884 return; 4885 4886 mtx_lock(&vnode_free_list_mtx); 4887 TAILQ_REMOVE(&mp->mnt_activevnodelist, *mvp, v_actfreelist); 4888 mtx_unlock(&vnode_free_list_mtx); 4889 mnt_vnode_markerfree_active(mvp, mp); 4890} 4891