1 /*- 2 * Copyright (c) 1989, 1993 3 * The Regents of the University of California. All rights reserved. 4 * (c) UNIX System Laboratories, Inc. 5 * All or some portions of this file are derived from material licensed 6 * to the University of California by American Telephone and Telegraph 7 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 8 * the permission of UNIX System Laboratories, Inc. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 4. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * @(#)vfs_subr.c 8.31 (Berkeley) 5/26/95 35 */ 36 37 /* 38 * External virtual filesystem routines 39 */ 40 41 #include <sys/cdefs.h> 42 __FBSDID("$FreeBSD$"); 43 44 #include "opt_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/refcount.h> 72 #include <sys/rwlock.h> 73 #include <sys/sched.h> 74 #include <sys/sleepqueue.h> 75 #include <sys/smp.h> 76 #include <sys/stat.h> 77 #include <sys/sysctl.h> 78 #include <sys/syslog.h> 79 #include <sys/vmmeter.h> 80 #include <sys/vnode.h> 81 #include <sys/watchdog.h> 82 83 #include <machine/stdarg.h> 84 85 #include <security/mac/mac_framework.h> 86 87 #include <vm/vm.h> 88 #include <vm/vm_object.h> 89 #include <vm/vm_extern.h> 90 #include <vm/pmap.h> 91 #include <vm/vm_map.h> 92 #include <vm/vm_page.h> 93 #include <vm/vm_kern.h> 94 #include <vm/uma.h> 95 96 #ifdef DDB 97 #include <ddb/ddb.h> 98 #endif 99 100 static void delmntque(struct vnode *vp); 101 static int flushbuflist(struct bufv *bufv, int flags, struct bufobj *bo, 102 int slpflag, int slptimeo); 103 static void syncer_shutdown(void *arg, int howto); 104 static int vtryrecycle(struct vnode *vp); 105 static void v_init_counters(struct vnode *); 106 static void v_incr_usecount(struct vnode *); 107 static void v_incr_devcount(struct vnode *); 108 static void v_decr_devcount(struct vnode *); 109 static void vnlru_free(int); 110 static void vgonel(struct vnode *); 111 static void vfs_knllock(void *arg); 112 static void vfs_knlunlock(void *arg); 113 static void vfs_knl_assert_locked(void *arg); 114 static void vfs_knl_assert_unlocked(void *arg); 115 static void destroy_vpollinfo(struct vpollinfo *vi); 116 117 /* 118 * Number of vnodes in existence. Increased whenever getnewvnode() 119 * allocates a new vnode, decreased in vdropl() for VI_DOOMED vnode. 120 */ 121 static unsigned long numvnodes; 122 123 SYSCTL_ULONG(_vfs, OID_AUTO, numvnodes, CTLFLAG_RD, &numvnodes, 0, 124 "Number of vnodes in existence"); 125 126 static u_long vnodes_created; 127 SYSCTL_ULONG(_vfs, OID_AUTO, vnodes_created, CTLFLAG_RD, &vnodes_created, 128 0, "Number of vnodes created by getnewvnode"); 129 130 /* 131 * Conversion tables for conversion from vnode types to inode formats 132 * and back. 133 */ 134 enum vtype iftovt_tab[16] = { 135 VNON, VFIFO, VCHR, VNON, VDIR, VNON, VBLK, VNON, 136 VREG, VNON, VLNK, VNON, VSOCK, VNON, VNON, VBAD, 137 }; 138 int vttoif_tab[10] = { 139 0, S_IFREG, S_IFDIR, S_IFBLK, S_IFCHR, S_IFLNK, 140 S_IFSOCK, S_IFIFO, S_IFMT, S_IFMT 141 }; 142 143 /* 144 * List of vnodes that are ready for recycling. 145 */ 146 static TAILQ_HEAD(freelst, vnode) vnode_free_list; 147 148 /* 149 * Free vnode target. Free vnodes may simply be files which have been stat'd 150 * but not read. This is somewhat common, and a small cache of such files 151 * should be kept to avoid recreation costs. 152 */ 153 static u_long wantfreevnodes; 154 SYSCTL_ULONG(_vfs, OID_AUTO, wantfreevnodes, CTLFLAG_RW, &wantfreevnodes, 0, ""); 155 /* Number of vnodes in the free list. */ 156 static u_long freevnodes; 157 SYSCTL_ULONG(_vfs, OID_AUTO, freevnodes, CTLFLAG_RD, &freevnodes, 0, 158 "Number of vnodes in the free list"); 159 160 static int vlru_allow_cache_src; 161 SYSCTL_INT(_vfs, OID_AUTO, vlru_allow_cache_src, CTLFLAG_RW, 162 &vlru_allow_cache_src, 0, "Allow vlru to reclaim source vnode"); 163 164 static u_long recycles_count; 165 SYSCTL_ULONG(_vfs, OID_AUTO, recycles, CTLFLAG_RD, &recycles_count, 0, 166 "Number of vnodes recycled to avoid exceding kern.maxvnodes"); 167 168 /* 169 * Various variables used for debugging the new implementation of 170 * reassignbuf(). 171 * XXX these are probably of (very) limited utility now. 172 */ 173 static int reassignbufcalls; 174 SYSCTL_INT(_vfs, OID_AUTO, reassignbufcalls, CTLFLAG_RW, &reassignbufcalls, 0, 175 "Number of calls to reassignbuf"); 176 177 static u_long free_owe_inact; 178 SYSCTL_ULONG(_vfs, OID_AUTO, free_owe_inact, CTLFLAG_RD, &free_owe_inact, 0, 179 "Number of times free vnodes kept on active list due to VFS " 180 "owing inactivation"); 181 182 /* 183 * Cache for the mount type id assigned to NFS. This is used for 184 * special checks in nfs/nfs_nqlease.c and vm/vnode_pager.c. 185 */ 186 int nfs_mount_type = -1; 187 188 /* To keep more than one thread at a time from running vfs_getnewfsid */ 189 static struct mtx mntid_mtx; 190 191 /* 192 * Lock for any access to the following: 193 * vnode_free_list 194 * numvnodes 195 * freevnodes 196 */ 197 static struct mtx vnode_free_list_mtx; 198 199 /* Publicly exported FS */ 200 struct nfs_public nfs_pub; 201 202 static uma_zone_t buf_trie_zone; 203 204 /* Zone for allocation of new vnodes - used exclusively by getnewvnode() */ 205 static uma_zone_t vnode_zone; 206 static uma_zone_t vnodepoll_zone; 207 208 /* 209 * The workitem queue. 210 * 211 * It is useful to delay writes of file data and filesystem metadata 212 * for tens of seconds so that quickly created and deleted files need 213 * not waste disk bandwidth being created and removed. To realize this, 214 * we append vnodes to a "workitem" queue. When running with a soft 215 * updates implementation, most pending metadata dependencies should 216 * not wait for more than a few seconds. Thus, mounted on block devices 217 * are delayed only about a half the time that file data is delayed. 218 * Similarly, directory updates are more critical, so are only delayed 219 * about a third the time that file data is delayed. Thus, there are 220 * SYNCER_MAXDELAY queues that are processed round-robin at a rate of 221 * one each second (driven off the filesystem syncer process). The 222 * syncer_delayno variable indicates the next queue that is to be processed. 223 * Items that need to be processed soon are placed in this queue: 224 * 225 * syncer_workitem_pending[syncer_delayno] 226 * 227 * A delay of fifteen seconds is done by placing the request fifteen 228 * entries later in the queue: 229 * 230 * syncer_workitem_pending[(syncer_delayno + 15) & syncer_mask] 231 * 232 */ 233 static int syncer_delayno; 234 static long syncer_mask; 235 LIST_HEAD(synclist, bufobj); 236 static struct synclist *syncer_workitem_pending; 237 /* 238 * The sync_mtx protects: 239 * bo->bo_synclist 240 * sync_vnode_count 241 * syncer_delayno 242 * syncer_state 243 * syncer_workitem_pending 244 * syncer_worklist_len 245 * rushjob 246 */ 247 static struct mtx sync_mtx; 248 static struct cv sync_wakeup; 249 250 #define SYNCER_MAXDELAY 32 251 static int syncer_maxdelay = SYNCER_MAXDELAY; /* maximum delay time */ 252 static int syncdelay = 30; /* max time to delay syncing data */ 253 static int filedelay = 30; /* time to delay syncing files */ 254 SYSCTL_INT(_kern, OID_AUTO, filedelay, CTLFLAG_RW, &filedelay, 0, 255 "Time to delay syncing files (in seconds)"); 256 static int dirdelay = 29; /* time to delay syncing directories */ 257 SYSCTL_INT(_kern, OID_AUTO, dirdelay, CTLFLAG_RW, &dirdelay, 0, 258 "Time to delay syncing directories (in seconds)"); 259 static int metadelay = 28; /* time to delay syncing metadata */ 260 SYSCTL_INT(_kern, OID_AUTO, metadelay, CTLFLAG_RW, &metadelay, 0, 261 "Time to delay syncing metadata (in seconds)"); 262 static int rushjob; /* number of slots to run ASAP */ 263 static int stat_rush_requests; /* number of times I/O speeded up */ 264 SYSCTL_INT(_debug, OID_AUTO, rush_requests, CTLFLAG_RW, &stat_rush_requests, 0, 265 "Number of times I/O speeded up (rush requests)"); 266 267 /* 268 * When shutting down the syncer, run it at four times normal speed. 269 */ 270 #define SYNCER_SHUTDOWN_SPEEDUP 4 271 static int sync_vnode_count; 272 static int syncer_worklist_len; 273 static enum { SYNCER_RUNNING, SYNCER_SHUTTING_DOWN, SYNCER_FINAL_DELAY } 274 syncer_state; 275 276 /* 277 * Number of vnodes we want to exist at any one time. This is mostly used 278 * to size hash tables in vnode-related code. It is normally not used in 279 * getnewvnode(), as wantfreevnodes is normally nonzero.) 280 * 281 * XXX desiredvnodes is historical cruft and should not exist. 282 */ 283 int desiredvnodes; 284 285 static int 286 sysctl_update_desiredvnodes(SYSCTL_HANDLER_ARGS) 287 { 288 int error, old_desiredvnodes; 289 290 old_desiredvnodes = desiredvnodes; 291 if ((error = sysctl_handle_int(oidp, arg1, arg2, req)) != 0) 292 return (error); 293 if (old_desiredvnodes != desiredvnodes) { 294 vfs_hash_changesize(desiredvnodes); 295 cache_changesize(desiredvnodes); 296 } 297 return (0); 298 } 299 300 SYSCTL_PROC(_kern, KERN_MAXVNODES, maxvnodes, 301 CTLTYPE_INT | CTLFLAG_MPSAFE | CTLFLAG_RW, &desiredvnodes, 0, 302 sysctl_update_desiredvnodes, "I", "Maximum number of vnodes"); 303 SYSCTL_ULONG(_kern, OID_AUTO, minvnodes, CTLFLAG_RW, 304 &wantfreevnodes, 0, "Minimum number of vnodes (legacy)"); 305 static int vnlru_nowhere; 306 SYSCTL_INT(_debug, OID_AUTO, vnlru_nowhere, CTLFLAG_RW, 307 &vnlru_nowhere, 0, "Number of times the vnlru process ran without success"); 308 309 /* Shift count for (uintptr_t)vp to initialize vp->v_hash. */ 310 static int vnsz2log; 311 312 /* 313 * Support for the bufobj clean & dirty pctrie. 314 */ 315 static void * 316 buf_trie_alloc(struct pctrie *ptree) 317 { 318 319 return uma_zalloc(buf_trie_zone, M_NOWAIT); 320 } 321 322 static void 323 buf_trie_free(struct pctrie *ptree, void *node) 324 { 325 326 uma_zfree(buf_trie_zone, node); 327 } 328 PCTRIE_DEFINE(BUF, buf, b_lblkno, buf_trie_alloc, buf_trie_free); 329 330 /* 331 * Initialize the vnode management data structures. 332 * 333 * Reevaluate the following cap on the number of vnodes after the physical 334 * memory size exceeds 512GB. In the limit, as the physical memory size 335 * grows, the ratio of physical pages to vnodes approaches sixteen to one. 336 */ 337 #ifndef MAXVNODES_MAX 338 #define MAXVNODES_MAX (512 * (1024 * 1024 * 1024 / (int)PAGE_SIZE / 16)) 339 #endif 340 static void 341 vntblinit(void *dummy __unused) 342 { 343 u_int i; 344 int physvnodes, virtvnodes; 345 346 /* 347 * Desiredvnodes is a function of the physical memory size and the 348 * kernel's heap size. Generally speaking, it scales with the 349 * physical memory size. The ratio of desiredvnodes to physical pages 350 * is one to four until desiredvnodes exceeds 98,304. Thereafter, the 351 * marginal ratio of desiredvnodes to physical pages is one to 352 * sixteen. However, desiredvnodes is limited by the kernel's heap 353 * size. The memory required by desiredvnodes vnodes and vm objects 354 * may not exceed one seventh of the kernel's heap size. 355 */ 356 physvnodes = maxproc + vm_cnt.v_page_count / 16 + 3 * min(98304 * 4, 357 vm_cnt.v_page_count) / 16; 358 virtvnodes = vm_kmem_size / (7 * (sizeof(struct vm_object) + 359 sizeof(struct vnode))); 360 desiredvnodes = min(physvnodes, virtvnodes); 361 if (desiredvnodes > MAXVNODES_MAX) { 362 if (bootverbose) 363 printf("Reducing kern.maxvnodes %d -> %d\n", 364 desiredvnodes, MAXVNODES_MAX); 365 desiredvnodes = MAXVNODES_MAX; 366 } 367 wantfreevnodes = desiredvnodes / 4; 368 mtx_init(&mntid_mtx, "mntid", NULL, MTX_DEF); 369 TAILQ_INIT(&vnode_free_list); 370 mtx_init(&vnode_free_list_mtx, "vnode_free_list", NULL, MTX_DEF); 371 vnode_zone = uma_zcreate("VNODE", sizeof (struct vnode), NULL, NULL, 372 NULL, NULL, UMA_ALIGN_PTR, 0); 373 vnodepoll_zone = uma_zcreate("VNODEPOLL", sizeof (struct vpollinfo), 374 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); 375 /* 376 * Preallocate enough nodes to support one-per buf so that 377 * we can not fail an insert. reassignbuf() callers can not 378 * tolerate the insertion failure. 379 */ 380 buf_trie_zone = uma_zcreate("BUF TRIE", pctrie_node_size(), 381 NULL, NULL, pctrie_zone_init, NULL, UMA_ALIGN_PTR, 382 UMA_ZONE_NOFREE | UMA_ZONE_VM); 383 uma_prealloc(buf_trie_zone, nbuf); 384 /* 385 * Initialize the filesystem syncer. 386 */ 387 syncer_workitem_pending = hashinit(syncer_maxdelay, M_VNODE, 388 &syncer_mask); 389 syncer_maxdelay = syncer_mask + 1; 390 mtx_init(&sync_mtx, "Syncer mtx", NULL, MTX_DEF); 391 cv_init(&sync_wakeup, "syncer"); 392 for (i = 1; i <= sizeof(struct vnode); i <<= 1) 393 vnsz2log++; 394 vnsz2log--; 395 } 396 SYSINIT(vfs, SI_SUB_VFS, SI_ORDER_FIRST, vntblinit, NULL); 397 398 399 /* 400 * Mark a mount point as busy. Used to synchronize access and to delay 401 * unmounting. Eventually, mountlist_mtx is not released on failure. 402 * 403 * vfs_busy() is a custom lock, it can block the caller. 404 * vfs_busy() only sleeps if the unmount is active on the mount point. 405 * For a mountpoint mp, vfs_busy-enforced lock is before lock of any 406 * vnode belonging to mp. 407 * 408 * Lookup uses vfs_busy() to traverse mount points. 409 * root fs var fs 410 * / vnode lock A / vnode lock (/var) D 411 * /var vnode lock B /log vnode lock(/var/log) E 412 * vfs_busy lock C vfs_busy lock F 413 * 414 * Within each file system, the lock order is C->A->B and F->D->E. 415 * 416 * When traversing across mounts, the system follows that lock order: 417 * 418 * C->A->B 419 * | 420 * +->F->D->E 421 * 422 * The lookup() process for namei("/var") illustrates the process: 423 * VOP_LOOKUP() obtains B while A is held 424 * vfs_busy() obtains a shared lock on F while A and B are held 425 * vput() releases lock on B 426 * vput() releases lock on A 427 * VFS_ROOT() obtains lock on D while shared lock on F is held 428 * vfs_unbusy() releases shared lock on F 429 * vn_lock() obtains lock on deadfs vnode vp_crossmp instead of A. 430 * Attempt to lock A (instead of vp_crossmp) while D is held would 431 * violate the global order, causing deadlocks. 432 * 433 * dounmount() locks B while F is drained. 434 */ 435 int 436 vfs_busy(struct mount *mp, int flags) 437 { 438 439 MPASS((flags & ~MBF_MASK) == 0); 440 CTR3(KTR_VFS, "%s: mp %p with flags %d", __func__, mp, flags); 441 442 MNT_ILOCK(mp); 443 MNT_REF(mp); 444 /* 445 * If mount point is currenly being unmounted, sleep until the 446 * mount point fate is decided. If thread doing the unmounting fails, 447 * it will clear MNTK_UNMOUNT flag before waking us up, indicating 448 * that this mount point has survived the unmount attempt and vfs_busy 449 * should retry. Otherwise the unmounter thread will set MNTK_REFEXPIRE 450 * flag in addition to MNTK_UNMOUNT, indicating that mount point is 451 * about to be really destroyed. vfs_busy needs to release its 452 * reference on the mount point in this case and return with ENOENT, 453 * telling the caller that mount mount it tried to busy is no longer 454 * valid. 455 */ 456 while (mp->mnt_kern_flag & MNTK_UNMOUNT) { 457 if (flags & MBF_NOWAIT || mp->mnt_kern_flag & MNTK_REFEXPIRE) { 458 MNT_REL(mp); 459 MNT_IUNLOCK(mp); 460 CTR1(KTR_VFS, "%s: failed busying before sleeping", 461 __func__); 462 return (ENOENT); 463 } 464 if (flags & MBF_MNTLSTLOCK) 465 mtx_unlock(&mountlist_mtx); 466 mp->mnt_kern_flag |= MNTK_MWAIT; 467 msleep(mp, MNT_MTX(mp), PVFS | PDROP, "vfs_busy", 0); 468 if (flags & MBF_MNTLSTLOCK) 469 mtx_lock(&mountlist_mtx); 470 MNT_ILOCK(mp); 471 } 472 if (flags & MBF_MNTLSTLOCK) 473 mtx_unlock(&mountlist_mtx); 474 mp->mnt_lockref++; 475 MNT_IUNLOCK(mp); 476 return (0); 477 } 478 479 /* 480 * Free a busy filesystem. 481 */ 482 void 483 vfs_unbusy(struct mount *mp) 484 { 485 486 CTR2(KTR_VFS, "%s: mp %p", __func__, mp); 487 MNT_ILOCK(mp); 488 MNT_REL(mp); 489 KASSERT(mp->mnt_lockref > 0, ("negative mnt_lockref")); 490 mp->mnt_lockref--; 491 if (mp->mnt_lockref == 0 && (mp->mnt_kern_flag & MNTK_DRAINING) != 0) { 492 MPASS(mp->mnt_kern_flag & MNTK_UNMOUNT); 493 CTR1(KTR_VFS, "%s: waking up waiters", __func__); 494 mp->mnt_kern_flag &= ~MNTK_DRAINING; 495 wakeup(&mp->mnt_lockref); 496 } 497 MNT_IUNLOCK(mp); 498 } 499 500 /* 501 * Lookup a mount point by filesystem identifier. 502 */ 503 struct mount * 504 vfs_getvfs(fsid_t *fsid) 505 { 506 struct mount *mp; 507 508 CTR2(KTR_VFS, "%s: fsid %p", __func__, fsid); 509 mtx_lock(&mountlist_mtx); 510 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 511 if (mp->mnt_stat.f_fsid.val[0] == fsid->val[0] && 512 mp->mnt_stat.f_fsid.val[1] == fsid->val[1]) { 513 vfs_ref(mp); 514 mtx_unlock(&mountlist_mtx); 515 return (mp); 516 } 517 } 518 mtx_unlock(&mountlist_mtx); 519 CTR2(KTR_VFS, "%s: lookup failed for %p id", __func__, fsid); 520 return ((struct mount *) 0); 521 } 522 523 /* 524 * Lookup a mount point by filesystem identifier, busying it before 525 * returning. 526 * 527 * To avoid congestion on mountlist_mtx, implement simple direct-mapped 528 * cache for popular filesystem identifiers. The cache is lockess, using 529 * the fact that struct mount's are never freed. In worst case we may 530 * get pointer to unmounted or even different filesystem, so we have to 531 * check what we got, and go slow way if so. 532 */ 533 struct mount * 534 vfs_busyfs(fsid_t *fsid) 535 { 536 #define FSID_CACHE_SIZE 256 537 typedef struct mount * volatile vmp_t; 538 static vmp_t cache[FSID_CACHE_SIZE]; 539 struct mount *mp; 540 int error; 541 uint32_t hash; 542 543 CTR2(KTR_VFS, "%s: fsid %p", __func__, fsid); 544 hash = fsid->val[0] ^ fsid->val[1]; 545 hash = (hash >> 16 ^ hash) & (FSID_CACHE_SIZE - 1); 546 mp = cache[hash]; 547 if (mp == NULL || 548 mp->mnt_stat.f_fsid.val[0] != fsid->val[0] || 549 mp->mnt_stat.f_fsid.val[1] != fsid->val[1]) 550 goto slow; 551 if (vfs_busy(mp, 0) != 0) { 552 cache[hash] = NULL; 553 goto slow; 554 } 555 if (mp->mnt_stat.f_fsid.val[0] == fsid->val[0] && 556 mp->mnt_stat.f_fsid.val[1] == fsid->val[1]) 557 return (mp); 558 else 559 vfs_unbusy(mp); 560 561 slow: 562 mtx_lock(&mountlist_mtx); 563 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 564 if (mp->mnt_stat.f_fsid.val[0] == fsid->val[0] && 565 mp->mnt_stat.f_fsid.val[1] == fsid->val[1]) { 566 error = vfs_busy(mp, MBF_MNTLSTLOCK); 567 if (error) { 568 cache[hash] = NULL; 569 mtx_unlock(&mountlist_mtx); 570 return (NULL); 571 } 572 cache[hash] = mp; 573 return (mp); 574 } 575 } 576 CTR2(KTR_VFS, "%s: lookup failed for %p id", __func__, fsid); 577 mtx_unlock(&mountlist_mtx); 578 return ((struct mount *) 0); 579 } 580 581 /* 582 * Check if a user can access privileged mount options. 583 */ 584 int 585 vfs_suser(struct mount *mp, struct thread *td) 586 { 587 int error; 588 589 /* 590 * If the thread is jailed, but this is not a jail-friendly file 591 * system, deny immediately. 592 */ 593 if (!(mp->mnt_vfc->vfc_flags & VFCF_JAIL) && jailed(td->td_ucred)) 594 return (EPERM); 595 596 /* 597 * If the file system was mounted outside the jail of the calling 598 * thread, deny immediately. 599 */ 600 if (prison_check(td->td_ucred, mp->mnt_cred) != 0) 601 return (EPERM); 602 603 /* 604 * If file system supports delegated administration, we don't check 605 * for the PRIV_VFS_MOUNT_OWNER privilege - it will be better verified 606 * by the file system itself. 607 * If this is not the user that did original mount, we check for 608 * the PRIV_VFS_MOUNT_OWNER privilege. 609 */ 610 if (!(mp->mnt_vfc->vfc_flags & VFCF_DELEGADMIN) && 611 mp->mnt_cred->cr_uid != td->td_ucred->cr_uid) { 612 if ((error = priv_check(td, PRIV_VFS_MOUNT_OWNER)) != 0) 613 return (error); 614 } 615 return (0); 616 } 617 618 /* 619 * Get a new unique fsid. Try to make its val[0] unique, since this value 620 * will be used to create fake device numbers for stat(). Also try (but 621 * not so hard) make its val[0] unique mod 2^16, since some emulators only 622 * support 16-bit device numbers. We end up with unique val[0]'s for the 623 * first 2^16 calls and unique val[0]'s mod 2^16 for the first 2^8 calls. 624 * 625 * Keep in mind that several mounts may be running in parallel. Starting 626 * the search one past where the previous search terminated is both a 627 * micro-optimization and a defense against returning the same fsid to 628 * different mounts. 629 */ 630 void 631 vfs_getnewfsid(struct mount *mp) 632 { 633 static uint16_t mntid_base; 634 struct mount *nmp; 635 fsid_t tfsid; 636 int mtype; 637 638 CTR2(KTR_VFS, "%s: mp %p", __func__, mp); 639 mtx_lock(&mntid_mtx); 640 mtype = mp->mnt_vfc->vfc_typenum; 641 tfsid.val[1] = mtype; 642 mtype = (mtype & 0xFF) << 24; 643 for (;;) { 644 tfsid.val[0] = makedev(255, 645 mtype | ((mntid_base & 0xFF00) << 8) | (mntid_base & 0xFF)); 646 mntid_base++; 647 if ((nmp = vfs_getvfs(&tfsid)) == NULL) 648 break; 649 vfs_rel(nmp); 650 } 651 mp->mnt_stat.f_fsid.val[0] = tfsid.val[0]; 652 mp->mnt_stat.f_fsid.val[1] = tfsid.val[1]; 653 mtx_unlock(&mntid_mtx); 654 } 655 656 /* 657 * Knob to control the precision of file timestamps: 658 * 659 * 0 = seconds only; nanoseconds zeroed. 660 * 1 = seconds and nanoseconds, accurate within 1/HZ. 661 * 2 = seconds and nanoseconds, truncated to microseconds. 662 * >=3 = seconds and nanoseconds, maximum precision. 663 */ 664 enum { TSP_SEC, TSP_HZ, TSP_USEC, TSP_NSEC }; 665 666 static int timestamp_precision = TSP_USEC; 667 SYSCTL_INT(_vfs, OID_AUTO, timestamp_precision, CTLFLAG_RW, 668 ×tamp_precision, 0, "File timestamp precision (0: seconds, " 669 "1: sec + ns accurate to 1/HZ, 2: sec + ns truncated to ms, " 670 "3+: sec + ns (max. precision))"); 671 672 /* 673 * Get a current timestamp. 674 */ 675 void 676 vfs_timestamp(struct timespec *tsp) 677 { 678 struct timeval tv; 679 680 switch (timestamp_precision) { 681 case TSP_SEC: 682 tsp->tv_sec = time_second; 683 tsp->tv_nsec = 0; 684 break; 685 case TSP_HZ: 686 getnanotime(tsp); 687 break; 688 case TSP_USEC: 689 microtime(&tv); 690 TIMEVAL_TO_TIMESPEC(&tv, tsp); 691 break; 692 case TSP_NSEC: 693 default: 694 nanotime(tsp); 695 break; 696 } 697 } 698 699 /* 700 * Set vnode attributes to VNOVAL 701 */ 702 void 703 vattr_null(struct vattr *vap) 704 { 705 706 vap->va_type = VNON; 707 vap->va_size = VNOVAL; 708 vap->va_bytes = VNOVAL; 709 vap->va_mode = VNOVAL; 710 vap->va_nlink = VNOVAL; 711 vap->va_uid = VNOVAL; 712 vap->va_gid = VNOVAL; 713 vap->va_fsid = VNOVAL; 714 vap->va_fileid = VNOVAL; 715 vap->va_blocksize = VNOVAL; 716 vap->va_rdev = VNOVAL; 717 vap->va_atime.tv_sec = VNOVAL; 718 vap->va_atime.tv_nsec = VNOVAL; 719 vap->va_mtime.tv_sec = VNOVAL; 720 vap->va_mtime.tv_nsec = VNOVAL; 721 vap->va_ctime.tv_sec = VNOVAL; 722 vap->va_ctime.tv_nsec = VNOVAL; 723 vap->va_birthtime.tv_sec = VNOVAL; 724 vap->va_birthtime.tv_nsec = VNOVAL; 725 vap->va_flags = VNOVAL; 726 vap->va_gen = VNOVAL; 727 vap->va_vaflags = 0; 728 } 729 730 /* 731 * This routine is called when we have too many vnodes. It attempts 732 * to free <count> vnodes and will potentially free vnodes that still 733 * have VM backing store (VM backing store is typically the cause 734 * of a vnode blowout so we want to do this). Therefore, this operation 735 * is not considered cheap. 736 * 737 * A number of conditions may prevent a vnode from being reclaimed. 738 * the buffer cache may have references on the vnode, a directory 739 * vnode may still have references due to the namei cache representing 740 * underlying files, or the vnode may be in active use. It is not 741 * desireable to reuse such vnodes. These conditions may cause the 742 * number of vnodes to reach some minimum value regardless of what 743 * you set kern.maxvnodes to. Do not set kern.maxvnodes too low. 744 */ 745 static int 746 vlrureclaim(struct mount *mp) 747 { 748 struct vnode *vp; 749 int done; 750 int trigger; 751 int usevnodes; 752 int count; 753 754 /* 755 * Calculate the trigger point, don't allow user 756 * screwups to blow us up. This prevents us from 757 * recycling vnodes with lots of resident pages. We 758 * aren't trying to free memory, we are trying to 759 * free vnodes. 760 */ 761 usevnodes = desiredvnodes; 762 if (usevnodes <= 0) 763 usevnodes = 1; 764 trigger = vm_cnt.v_page_count * 2 / usevnodes; 765 done = 0; 766 vn_start_write(NULL, &mp, V_WAIT); 767 MNT_ILOCK(mp); 768 count = mp->mnt_nvnodelistsize / 10 + 1; 769 while (count != 0) { 770 vp = TAILQ_FIRST(&mp->mnt_nvnodelist); 771 while (vp != NULL && vp->v_type == VMARKER) 772 vp = TAILQ_NEXT(vp, v_nmntvnodes); 773 if (vp == NULL) 774 break; 775 TAILQ_REMOVE(&mp->mnt_nvnodelist, vp, v_nmntvnodes); 776 TAILQ_INSERT_TAIL(&mp->mnt_nvnodelist, vp, v_nmntvnodes); 777 --count; 778 if (!VI_TRYLOCK(vp)) 779 goto next_iter; 780 /* 781 * If it's been deconstructed already, it's still 782 * referenced, or it exceeds the trigger, skip it. 783 */ 784 if (vp->v_usecount || 785 (!vlru_allow_cache_src && 786 !LIST_EMPTY(&(vp)->v_cache_src)) || 787 (vp->v_iflag & VI_DOOMED) != 0 || (vp->v_object != NULL && 788 vp->v_object->resident_page_count > trigger)) { 789 VI_UNLOCK(vp); 790 goto next_iter; 791 } 792 MNT_IUNLOCK(mp); 793 vholdl(vp); 794 if (VOP_LOCK(vp, LK_INTERLOCK|LK_EXCLUSIVE|LK_NOWAIT)) { 795 vdrop(vp); 796 goto next_iter_mntunlocked; 797 } 798 VI_LOCK(vp); 799 /* 800 * v_usecount may have been bumped after VOP_LOCK() dropped 801 * the vnode interlock and before it was locked again. 802 * 803 * It is not necessary to recheck VI_DOOMED because it can 804 * only be set by another thread that holds both the vnode 805 * lock and vnode interlock. If another thread has the 806 * vnode lock before we get to VOP_LOCK() and obtains the 807 * vnode interlock after VOP_LOCK() drops the vnode 808 * interlock, the other thread will be unable to drop the 809 * vnode lock before our VOP_LOCK() call fails. 810 */ 811 if (vp->v_usecount || 812 (!vlru_allow_cache_src && 813 !LIST_EMPTY(&(vp)->v_cache_src)) || 814 (vp->v_object != NULL && 815 vp->v_object->resident_page_count > trigger)) { 816 VOP_UNLOCK(vp, LK_INTERLOCK); 817 vdrop(vp); 818 goto next_iter_mntunlocked; 819 } 820 KASSERT((vp->v_iflag & VI_DOOMED) == 0, 821 ("VI_DOOMED unexpectedly detected in vlrureclaim()")); 822 atomic_add_long(&recycles_count, 1); 823 vgonel(vp); 824 VOP_UNLOCK(vp, 0); 825 vdropl(vp); 826 done++; 827 next_iter_mntunlocked: 828 if (!should_yield()) 829 goto relock_mnt; 830 goto yield; 831 next_iter: 832 if (!should_yield()) 833 continue; 834 MNT_IUNLOCK(mp); 835 yield: 836 kern_yield(PRI_USER); 837 relock_mnt: 838 MNT_ILOCK(mp); 839 } 840 MNT_IUNLOCK(mp); 841 vn_finished_write(mp); 842 return done; 843 } 844 845 /* 846 * Attempt to keep the free list at wantfreevnodes length. 847 */ 848 static void 849 vnlru_free(int count) 850 { 851 struct vnode *vp; 852 853 mtx_assert(&vnode_free_list_mtx, MA_OWNED); 854 for (; count > 0; count--) { 855 vp = TAILQ_FIRST(&vnode_free_list); 856 /* 857 * The list can be modified while the free_list_mtx 858 * has been dropped and vp could be NULL here. 859 */ 860 if (!vp) 861 break; 862 VNASSERT(vp->v_op != NULL, vp, 863 ("vnlru_free: vnode already reclaimed.")); 864 KASSERT((vp->v_iflag & VI_FREE) != 0, 865 ("Removing vnode not on freelist")); 866 KASSERT((vp->v_iflag & VI_ACTIVE) == 0, 867 ("Mangling active vnode")); 868 TAILQ_REMOVE(&vnode_free_list, vp, v_actfreelist); 869 /* 870 * Don't recycle if we can't get the interlock. 871 */ 872 if (!VI_TRYLOCK(vp)) { 873 TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_actfreelist); 874 continue; 875 } 876 VNASSERT((vp->v_iflag & VI_FREE) != 0 && vp->v_holdcnt == 0, 877 vp, ("vp inconsistent on freelist")); 878 879 /* 880 * The clear of VI_FREE prevents activation of the 881 * vnode. There is no sense in putting the vnode on 882 * the mount point active list, only to remove it 883 * later during recycling. Inline the relevant part 884 * of vholdl(), to avoid triggering assertions or 885 * activating. 886 */ 887 freevnodes--; 888 vp->v_iflag &= ~VI_FREE; 889 refcount_acquire(&vp->v_holdcnt); 890 891 mtx_unlock(&vnode_free_list_mtx); 892 VI_UNLOCK(vp); 893 vtryrecycle(vp); 894 /* 895 * If the recycled succeeded this vdrop will actually free 896 * the vnode. If not it will simply place it back on 897 * the free list. 898 */ 899 vdrop(vp); 900 mtx_lock(&vnode_free_list_mtx); 901 } 902 } 903 /* 904 * Attempt to recycle vnodes in a context that is always safe to block. 905 * Calling vlrurecycle() from the bowels of filesystem code has some 906 * interesting deadlock problems. 907 */ 908 static struct proc *vnlruproc; 909 static int vnlruproc_sig; 910 911 static void 912 vnlru_proc(void) 913 { 914 struct mount *mp, *nmp; 915 int done; 916 struct proc *p = vnlruproc; 917 918 EVENTHANDLER_REGISTER(shutdown_pre_sync, kproc_shutdown, p, 919 SHUTDOWN_PRI_FIRST); 920 921 for (;;) { 922 kproc_suspend_check(p); 923 mtx_lock(&vnode_free_list_mtx); 924 if (freevnodes > wantfreevnodes) 925 vnlru_free(freevnodes - wantfreevnodes); 926 if (numvnodes <= desiredvnodes * 9 / 10) { 927 vnlruproc_sig = 0; 928 wakeup(&vnlruproc_sig); 929 msleep(vnlruproc, &vnode_free_list_mtx, 930 PVFS|PDROP, "vlruwt", hz); 931 continue; 932 } 933 mtx_unlock(&vnode_free_list_mtx); 934 done = 0; 935 mtx_lock(&mountlist_mtx); 936 for (mp = TAILQ_FIRST(&mountlist); mp != NULL; mp = nmp) { 937 if (vfs_busy(mp, MBF_NOWAIT | MBF_MNTLSTLOCK)) { 938 nmp = TAILQ_NEXT(mp, mnt_list); 939 continue; 940 } 941 done += vlrureclaim(mp); 942 mtx_lock(&mountlist_mtx); 943 nmp = TAILQ_NEXT(mp, mnt_list); 944 vfs_unbusy(mp); 945 } 946 mtx_unlock(&mountlist_mtx); 947 if (done == 0) { 948 #if 0 949 /* These messages are temporary debugging aids */ 950 if (vnlru_nowhere < 5) 951 printf("vnlru process getting nowhere..\n"); 952 else if (vnlru_nowhere == 5) 953 printf("vnlru process messages stopped.\n"); 954 #endif 955 vnlru_nowhere++; 956 tsleep(vnlruproc, PPAUSE, "vlrup", hz * 3); 957 } else 958 kern_yield(PRI_USER); 959 } 960 } 961 962 static struct kproc_desc vnlru_kp = { 963 "vnlru", 964 vnlru_proc, 965 &vnlruproc 966 }; 967 SYSINIT(vnlru, SI_SUB_KTHREAD_UPDATE, SI_ORDER_FIRST, kproc_start, 968 &vnlru_kp); 969 970 /* 971 * Routines having to do with the management of the vnode table. 972 */ 973 974 /* 975 * Try to recycle a freed vnode. We abort if anyone picks up a reference 976 * before we actually vgone(). This function must be called with the vnode 977 * held to prevent the vnode from being returned to the free list midway 978 * through vgone(). 979 */ 980 static int 981 vtryrecycle(struct vnode *vp) 982 { 983 struct mount *vnmp; 984 985 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 986 VNASSERT(vp->v_holdcnt, vp, 987 ("vtryrecycle: Recycling vp %p without a reference.", vp)); 988 /* 989 * This vnode may found and locked via some other list, if so we 990 * can't recycle it yet. 991 */ 992 if (VOP_LOCK(vp, LK_EXCLUSIVE | LK_NOWAIT) != 0) { 993 CTR2(KTR_VFS, 994 "%s: impossible to recycle, vp %p lock is already held", 995 __func__, vp); 996 return (EWOULDBLOCK); 997 } 998 /* 999 * Don't recycle if its filesystem is being suspended. 1000 */ 1001 if (vn_start_write(vp, &vnmp, V_NOWAIT) != 0) { 1002 VOP_UNLOCK(vp, 0); 1003 CTR2(KTR_VFS, 1004 "%s: impossible to recycle, cannot start the write for %p", 1005 __func__, vp); 1006 return (EBUSY); 1007 } 1008 /* 1009 * If we got this far, we need to acquire the interlock and see if 1010 * anyone picked up this vnode from another list. If not, we will 1011 * mark it with DOOMED via vgonel() so that anyone who does find it 1012 * will skip over it. 1013 */ 1014 VI_LOCK(vp); 1015 if (vp->v_usecount) { 1016 VOP_UNLOCK(vp, LK_INTERLOCK); 1017 vn_finished_write(vnmp); 1018 CTR2(KTR_VFS, 1019 "%s: impossible to recycle, %p is already referenced", 1020 __func__, vp); 1021 return (EBUSY); 1022 } 1023 if ((vp->v_iflag & VI_DOOMED) == 0) { 1024 atomic_add_long(&recycles_count, 1); 1025 vgonel(vp); 1026 } 1027 VOP_UNLOCK(vp, LK_INTERLOCK); 1028 vn_finished_write(vnmp); 1029 return (0); 1030 } 1031 1032 /* 1033 * Wait for available vnodes. 1034 */ 1035 static int 1036 getnewvnode_wait(int suspended) 1037 { 1038 1039 mtx_assert(&vnode_free_list_mtx, MA_OWNED); 1040 if (numvnodes > desiredvnodes) { 1041 if (suspended) { 1042 /* 1043 * File system is beeing suspended, we cannot risk a 1044 * deadlock here, so allocate new vnode anyway. 1045 */ 1046 if (freevnodes > wantfreevnodes) 1047 vnlru_free(freevnodes - wantfreevnodes); 1048 return (0); 1049 } 1050 if (vnlruproc_sig == 0) { 1051 vnlruproc_sig = 1; /* avoid unnecessary wakeups */ 1052 wakeup(vnlruproc); 1053 } 1054 msleep(&vnlruproc_sig, &vnode_free_list_mtx, PVFS, 1055 "vlruwk", hz); 1056 } 1057 return (numvnodes > desiredvnodes ? ENFILE : 0); 1058 } 1059 1060 void 1061 getnewvnode_reserve(u_int count) 1062 { 1063 struct thread *td; 1064 1065 td = curthread; 1066 /* First try to be quick and racy. */ 1067 if (atomic_fetchadd_long(&numvnodes, count) + count <= desiredvnodes) { 1068 td->td_vp_reserv += count; 1069 return; 1070 } else 1071 atomic_subtract_long(&numvnodes, count); 1072 1073 mtx_lock(&vnode_free_list_mtx); 1074 while (count > 0) { 1075 if (getnewvnode_wait(0) == 0) { 1076 count--; 1077 td->td_vp_reserv++; 1078 atomic_add_long(&numvnodes, 1); 1079 } 1080 } 1081 mtx_unlock(&vnode_free_list_mtx); 1082 } 1083 1084 void 1085 getnewvnode_drop_reserve(void) 1086 { 1087 struct thread *td; 1088 1089 td = curthread; 1090 atomic_subtract_long(&numvnodes, td->td_vp_reserv); 1091 td->td_vp_reserv = 0; 1092 } 1093 1094 /* 1095 * Return the next vnode from the free list. 1096 */ 1097 int 1098 getnewvnode(const char *tag, struct mount *mp, struct vop_vector *vops, 1099 struct vnode **vpp) 1100 { 1101 struct vnode *vp; 1102 struct bufobj *bo; 1103 struct thread *td; 1104 int error; 1105 1106 CTR3(KTR_VFS, "%s: mp %p with tag %s", __func__, mp, tag); 1107 vp = NULL; 1108 td = curthread; 1109 if (td->td_vp_reserv > 0) { 1110 td->td_vp_reserv -= 1; 1111 goto alloc; 1112 } 1113 mtx_lock(&vnode_free_list_mtx); 1114 /* 1115 * Lend our context to reclaim vnodes if they've exceeded the max. 1116 */ 1117 if (freevnodes > wantfreevnodes) 1118 vnlru_free(1); 1119 error = getnewvnode_wait(mp != NULL && (mp->mnt_kern_flag & 1120 MNTK_SUSPEND)); 1121 #if 0 /* XXX Not all VFS_VGET/ffs_vget callers check returns. */ 1122 if (error != 0) { 1123 mtx_unlock(&vnode_free_list_mtx); 1124 return (error); 1125 } 1126 #endif 1127 atomic_add_long(&numvnodes, 1); 1128 mtx_unlock(&vnode_free_list_mtx); 1129 alloc: 1130 atomic_add_long(&vnodes_created, 1); 1131 vp = (struct vnode *) uma_zalloc(vnode_zone, M_WAITOK|M_ZERO); 1132 /* 1133 * Setup locks. 1134 */ 1135 vp->v_vnlock = &vp->v_lock; 1136 mtx_init(&vp->v_interlock, "vnode interlock", NULL, MTX_DEF); 1137 /* 1138 * By default, don't allow shared locks unless filesystems 1139 * opt-in. 1140 */ 1141 lockinit(vp->v_vnlock, PVFS, tag, VLKTIMEOUT, LK_NOSHARE | LK_IS_VNODE); 1142 /* 1143 * Initialize bufobj. 1144 */ 1145 bo = &vp->v_bufobj; 1146 bo->__bo_vnode = vp; 1147 rw_init(BO_LOCKPTR(bo), "bufobj interlock"); 1148 bo->bo_ops = &buf_ops_bio; 1149 bo->bo_private = vp; 1150 TAILQ_INIT(&bo->bo_clean.bv_hd); 1151 TAILQ_INIT(&bo->bo_dirty.bv_hd); 1152 /* 1153 * Initialize namecache. 1154 */ 1155 LIST_INIT(&vp->v_cache_src); 1156 TAILQ_INIT(&vp->v_cache_dst); 1157 /* 1158 * Finalize various vnode identity bits. 1159 */ 1160 vp->v_type = VNON; 1161 vp->v_tag = tag; 1162 vp->v_op = vops; 1163 v_init_counters(vp); 1164 vp->v_data = NULL; 1165 #ifdef MAC 1166 mac_vnode_init(vp); 1167 if (mp != NULL && (mp->mnt_flag & MNT_MULTILABEL) == 0) 1168 mac_vnode_associate_singlelabel(mp, vp); 1169 else if (mp == NULL && vops != &dead_vnodeops) 1170 printf("NULL mp in getnewvnode()\n"); 1171 #endif 1172 if (mp != NULL) { 1173 bo->bo_bsize = mp->mnt_stat.f_iosize; 1174 if ((mp->mnt_kern_flag & MNTK_NOKNOTE) != 0) 1175 vp->v_vflag |= VV_NOKNOTE; 1176 } 1177 rangelock_init(&vp->v_rl); 1178 1179 /* 1180 * For the filesystems which do not use vfs_hash_insert(), 1181 * still initialize v_hash to have vfs_hash_index() useful. 1182 * E.g., nullfs uses vfs_hash_index() on the lower vnode for 1183 * its own hashing. 1184 */ 1185 vp->v_hash = (uintptr_t)vp >> vnsz2log; 1186 1187 *vpp = vp; 1188 return (0); 1189 } 1190 1191 /* 1192 * Delete from old mount point vnode list, if on one. 1193 */ 1194 static void 1195 delmntque(struct vnode *vp) 1196 { 1197 struct mount *mp; 1198 int active; 1199 1200 mp = vp->v_mount; 1201 if (mp == NULL) 1202 return; 1203 MNT_ILOCK(mp); 1204 VI_LOCK(vp); 1205 KASSERT(mp->mnt_activevnodelistsize <= mp->mnt_nvnodelistsize, 1206 ("Active vnode list size %d > Vnode list size %d", 1207 mp->mnt_activevnodelistsize, mp->mnt_nvnodelistsize)); 1208 active = vp->v_iflag & VI_ACTIVE; 1209 vp->v_iflag &= ~VI_ACTIVE; 1210 if (active) { 1211 mtx_lock(&vnode_free_list_mtx); 1212 TAILQ_REMOVE(&mp->mnt_activevnodelist, vp, v_actfreelist); 1213 mp->mnt_activevnodelistsize--; 1214 mtx_unlock(&vnode_free_list_mtx); 1215 } 1216 vp->v_mount = NULL; 1217 VI_UNLOCK(vp); 1218 VNASSERT(mp->mnt_nvnodelistsize > 0, vp, 1219 ("bad mount point vnode list size")); 1220 TAILQ_REMOVE(&mp->mnt_nvnodelist, vp, v_nmntvnodes); 1221 mp->mnt_nvnodelistsize--; 1222 MNT_REL(mp); 1223 MNT_IUNLOCK(mp); 1224 } 1225 1226 static void 1227 insmntque_stddtr(struct vnode *vp, void *dtr_arg) 1228 { 1229 1230 vp->v_data = NULL; 1231 vp->v_op = &dead_vnodeops; 1232 vgone(vp); 1233 vput(vp); 1234 } 1235 1236 /* 1237 * Insert into list of vnodes for the new mount point, if available. 1238 */ 1239 int 1240 insmntque1(struct vnode *vp, struct mount *mp, 1241 void (*dtr)(struct vnode *, void *), void *dtr_arg) 1242 { 1243 1244 KASSERT(vp->v_mount == NULL, 1245 ("insmntque: vnode already on per mount vnode list")); 1246 VNASSERT(mp != NULL, vp, ("Don't call insmntque(foo, NULL)")); 1247 ASSERT_VOP_ELOCKED(vp, "insmntque: non-locked vp"); 1248 1249 /* 1250 * We acquire the vnode interlock early to ensure that the 1251 * vnode cannot be recycled by another process releasing a 1252 * holdcnt on it before we get it on both the vnode list 1253 * and the active vnode list. The mount mutex protects only 1254 * manipulation of the vnode list and the vnode freelist 1255 * mutex protects only manipulation of the active vnode list. 1256 * Hence the need to hold the vnode interlock throughout. 1257 */ 1258 MNT_ILOCK(mp); 1259 VI_LOCK(vp); 1260 if (((mp->mnt_kern_flag & MNTK_NOINSMNTQ) != 0 && 1261 ((mp->mnt_kern_flag & MNTK_UNMOUNTF) != 0 || 1262 mp->mnt_nvnodelistsize == 0)) && 1263 (vp->v_vflag & VV_FORCEINSMQ) == 0) { 1264 VI_UNLOCK(vp); 1265 MNT_IUNLOCK(mp); 1266 if (dtr != NULL) 1267 dtr(vp, dtr_arg); 1268 return (EBUSY); 1269 } 1270 vp->v_mount = mp; 1271 MNT_REF(mp); 1272 TAILQ_INSERT_TAIL(&mp->mnt_nvnodelist, vp, v_nmntvnodes); 1273 VNASSERT(mp->mnt_nvnodelistsize >= 0, vp, 1274 ("neg mount point vnode list size")); 1275 mp->mnt_nvnodelistsize++; 1276 KASSERT((vp->v_iflag & VI_ACTIVE) == 0, 1277 ("Activating already active vnode")); 1278 vp->v_iflag |= VI_ACTIVE; 1279 mtx_lock(&vnode_free_list_mtx); 1280 TAILQ_INSERT_HEAD(&mp->mnt_activevnodelist, vp, v_actfreelist); 1281 mp->mnt_activevnodelistsize++; 1282 mtx_unlock(&vnode_free_list_mtx); 1283 VI_UNLOCK(vp); 1284 MNT_IUNLOCK(mp); 1285 return (0); 1286 } 1287 1288 int 1289 insmntque(struct vnode *vp, struct mount *mp) 1290 { 1291 1292 return (insmntque1(vp, mp, insmntque_stddtr, NULL)); 1293 } 1294 1295 /* 1296 * Flush out and invalidate all buffers associated with a bufobj 1297 * Called with the underlying object locked. 1298 */ 1299 int 1300 bufobj_invalbuf(struct bufobj *bo, int flags, int slpflag, int slptimeo) 1301 { 1302 int error; 1303 1304 BO_LOCK(bo); 1305 if (flags & V_SAVE) { 1306 error = bufobj_wwait(bo, slpflag, slptimeo); 1307 if (error) { 1308 BO_UNLOCK(bo); 1309 return (error); 1310 } 1311 if (bo->bo_dirty.bv_cnt > 0) { 1312 BO_UNLOCK(bo); 1313 if ((error = BO_SYNC(bo, MNT_WAIT)) != 0) 1314 return (error); 1315 /* 1316 * XXX We could save a lock/unlock if this was only 1317 * enabled under INVARIANTS 1318 */ 1319 BO_LOCK(bo); 1320 if (bo->bo_numoutput > 0 || bo->bo_dirty.bv_cnt > 0) 1321 panic("vinvalbuf: dirty bufs"); 1322 } 1323 } 1324 /* 1325 * If you alter this loop please notice that interlock is dropped and 1326 * reacquired in flushbuflist. Special care is needed to ensure that 1327 * no race conditions occur from this. 1328 */ 1329 do { 1330 error = flushbuflist(&bo->bo_clean, 1331 flags, bo, slpflag, slptimeo); 1332 if (error == 0 && !(flags & V_CLEANONLY)) 1333 error = flushbuflist(&bo->bo_dirty, 1334 flags, bo, slpflag, slptimeo); 1335 if (error != 0 && error != EAGAIN) { 1336 BO_UNLOCK(bo); 1337 return (error); 1338 } 1339 } while (error != 0); 1340 1341 /* 1342 * Wait for I/O to complete. XXX needs cleaning up. The vnode can 1343 * have write I/O in-progress but if there is a VM object then the 1344 * VM object can also have read-I/O in-progress. 1345 */ 1346 do { 1347 bufobj_wwait(bo, 0, 0); 1348 BO_UNLOCK(bo); 1349 if (bo->bo_object != NULL) { 1350 VM_OBJECT_WLOCK(bo->bo_object); 1351 vm_object_pip_wait(bo->bo_object, "bovlbx"); 1352 VM_OBJECT_WUNLOCK(bo->bo_object); 1353 } 1354 BO_LOCK(bo); 1355 } while (bo->bo_numoutput > 0); 1356 BO_UNLOCK(bo); 1357 1358 /* 1359 * Destroy the copy in the VM cache, too. 1360 */ 1361 if (bo->bo_object != NULL && 1362 (flags & (V_ALT | V_NORMAL | V_CLEANONLY)) == 0) { 1363 VM_OBJECT_WLOCK(bo->bo_object); 1364 vm_object_page_remove(bo->bo_object, 0, 0, (flags & V_SAVE) ? 1365 OBJPR_CLEANONLY : 0); 1366 VM_OBJECT_WUNLOCK(bo->bo_object); 1367 } 1368 1369 #ifdef INVARIANTS 1370 BO_LOCK(bo); 1371 if ((flags & (V_ALT | V_NORMAL | V_CLEANONLY)) == 0 && 1372 (bo->bo_dirty.bv_cnt > 0 || bo->bo_clean.bv_cnt > 0)) 1373 panic("vinvalbuf: flush failed"); 1374 BO_UNLOCK(bo); 1375 #endif 1376 return (0); 1377 } 1378 1379 /* 1380 * Flush out and invalidate all buffers associated with a vnode. 1381 * Called with the underlying object locked. 1382 */ 1383 int 1384 vinvalbuf(struct vnode *vp, int flags, int slpflag, int slptimeo) 1385 { 1386 1387 CTR3(KTR_VFS, "%s: vp %p with flags %d", __func__, vp, flags); 1388 ASSERT_VOP_LOCKED(vp, "vinvalbuf"); 1389 if (vp->v_object != NULL && vp->v_object->handle != vp) 1390 return (0); 1391 return (bufobj_invalbuf(&vp->v_bufobj, flags, slpflag, slptimeo)); 1392 } 1393 1394 /* 1395 * Flush out buffers on the specified list. 1396 * 1397 */ 1398 static int 1399 flushbuflist(struct bufv *bufv, int flags, struct bufobj *bo, int slpflag, 1400 int slptimeo) 1401 { 1402 struct buf *bp, *nbp; 1403 int retval, error; 1404 daddr_t lblkno; 1405 b_xflags_t xflags; 1406 1407 ASSERT_BO_WLOCKED(bo); 1408 1409 retval = 0; 1410 TAILQ_FOREACH_SAFE(bp, &bufv->bv_hd, b_bobufs, nbp) { 1411 if (((flags & V_NORMAL) && (bp->b_xflags & BX_ALTDATA)) || 1412 ((flags & V_ALT) && (bp->b_xflags & BX_ALTDATA) == 0)) { 1413 continue; 1414 } 1415 lblkno = 0; 1416 xflags = 0; 1417 if (nbp != NULL) { 1418 lblkno = nbp->b_lblkno; 1419 xflags = nbp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN); 1420 } 1421 retval = EAGAIN; 1422 error = BUF_TIMELOCK(bp, 1423 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, BO_LOCKPTR(bo), 1424 "flushbuf", slpflag, slptimeo); 1425 if (error) { 1426 BO_LOCK(bo); 1427 return (error != ENOLCK ? error : EAGAIN); 1428 } 1429 KASSERT(bp->b_bufobj == bo, 1430 ("bp %p wrong b_bufobj %p should be %p", 1431 bp, bp->b_bufobj, bo)); 1432 if (bp->b_bufobj != bo) { /* XXX: necessary ? */ 1433 BUF_UNLOCK(bp); 1434 BO_LOCK(bo); 1435 return (EAGAIN); 1436 } 1437 /* 1438 * XXX Since there are no node locks for NFS, I 1439 * believe there is a slight chance that a delayed 1440 * write will occur while sleeping just above, so 1441 * check for it. 1442 */ 1443 if (((bp->b_flags & (B_DELWRI | B_INVAL)) == B_DELWRI) && 1444 (flags & V_SAVE)) { 1445 bremfree(bp); 1446 bp->b_flags |= B_ASYNC; 1447 bwrite(bp); 1448 BO_LOCK(bo); 1449 return (EAGAIN); /* XXX: why not loop ? */ 1450 } 1451 bremfree(bp); 1452 bp->b_flags |= (B_INVAL | B_RELBUF); 1453 bp->b_flags &= ~B_ASYNC; 1454 brelse(bp); 1455 BO_LOCK(bo); 1456 if (nbp != NULL && 1457 (nbp->b_bufobj != bo || 1458 nbp->b_lblkno != lblkno || 1459 (nbp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN)) != xflags)) 1460 break; /* nbp invalid */ 1461 } 1462 return (retval); 1463 } 1464 1465 /* 1466 * Truncate a file's buffer and pages to a specified length. This 1467 * is in lieu of the old vinvalbuf mechanism, which performed unneeded 1468 * sync activity. 1469 */ 1470 int 1471 vtruncbuf(struct vnode *vp, struct ucred *cred, off_t length, int blksize) 1472 { 1473 struct buf *bp, *nbp; 1474 int anyfreed; 1475 int trunclbn; 1476 struct bufobj *bo; 1477 1478 CTR5(KTR_VFS, "%s: vp %p with cred %p and block %d:%ju", __func__, 1479 vp, cred, blksize, (uintmax_t)length); 1480 1481 /* 1482 * Round up to the *next* lbn. 1483 */ 1484 trunclbn = (length + blksize - 1) / blksize; 1485 1486 ASSERT_VOP_LOCKED(vp, "vtruncbuf"); 1487 restart: 1488 bo = &vp->v_bufobj; 1489 BO_LOCK(bo); 1490 anyfreed = 1; 1491 for (;anyfreed;) { 1492 anyfreed = 0; 1493 TAILQ_FOREACH_SAFE(bp, &bo->bo_clean.bv_hd, b_bobufs, nbp) { 1494 if (bp->b_lblkno < trunclbn) 1495 continue; 1496 if (BUF_LOCK(bp, 1497 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, 1498 BO_LOCKPTR(bo)) == ENOLCK) 1499 goto restart; 1500 1501 bremfree(bp); 1502 bp->b_flags |= (B_INVAL | B_RELBUF); 1503 bp->b_flags &= ~B_ASYNC; 1504 brelse(bp); 1505 anyfreed = 1; 1506 1507 BO_LOCK(bo); 1508 if (nbp != NULL && 1509 (((nbp->b_xflags & BX_VNCLEAN) == 0) || 1510 (nbp->b_vp != vp) || 1511 (nbp->b_flags & B_DELWRI))) { 1512 BO_UNLOCK(bo); 1513 goto restart; 1514 } 1515 } 1516 1517 TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) { 1518 if (bp->b_lblkno < trunclbn) 1519 continue; 1520 if (BUF_LOCK(bp, 1521 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, 1522 BO_LOCKPTR(bo)) == ENOLCK) 1523 goto restart; 1524 bremfree(bp); 1525 bp->b_flags |= (B_INVAL | B_RELBUF); 1526 bp->b_flags &= ~B_ASYNC; 1527 brelse(bp); 1528 anyfreed = 1; 1529 1530 BO_LOCK(bo); 1531 if (nbp != NULL && 1532 (((nbp->b_xflags & BX_VNDIRTY) == 0) || 1533 (nbp->b_vp != vp) || 1534 (nbp->b_flags & B_DELWRI) == 0)) { 1535 BO_UNLOCK(bo); 1536 goto restart; 1537 } 1538 } 1539 } 1540 1541 if (length > 0) { 1542 restartsync: 1543 TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) { 1544 if (bp->b_lblkno > 0) 1545 continue; 1546 /* 1547 * Since we hold the vnode lock this should only 1548 * fail if we're racing with the buf daemon. 1549 */ 1550 if (BUF_LOCK(bp, 1551 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, 1552 BO_LOCKPTR(bo)) == ENOLCK) { 1553 goto restart; 1554 } 1555 VNASSERT((bp->b_flags & B_DELWRI), vp, 1556 ("buf(%p) on dirty queue without DELWRI", bp)); 1557 1558 bremfree(bp); 1559 bawrite(bp); 1560 BO_LOCK(bo); 1561 goto restartsync; 1562 } 1563 } 1564 1565 bufobj_wwait(bo, 0, 0); 1566 BO_UNLOCK(bo); 1567 vnode_pager_setsize(vp, length); 1568 1569 return (0); 1570 } 1571 1572 static void 1573 buf_vlist_remove(struct buf *bp) 1574 { 1575 struct bufv *bv; 1576 1577 KASSERT(bp->b_bufobj != NULL, ("No b_bufobj %p", bp)); 1578 ASSERT_BO_WLOCKED(bp->b_bufobj); 1579 KASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) != 1580 (BX_VNDIRTY|BX_VNCLEAN), 1581 ("buf_vlist_remove: Buf %p is on two lists", bp)); 1582 if (bp->b_xflags & BX_VNDIRTY) 1583 bv = &bp->b_bufobj->bo_dirty; 1584 else 1585 bv = &bp->b_bufobj->bo_clean; 1586 BUF_PCTRIE_REMOVE(&bv->bv_root, bp->b_lblkno); 1587 TAILQ_REMOVE(&bv->bv_hd, bp, b_bobufs); 1588 bv->bv_cnt--; 1589 bp->b_xflags &= ~(BX_VNDIRTY | BX_VNCLEAN); 1590 } 1591 1592 /* 1593 * Add the buffer to the sorted clean or dirty block list. 1594 * 1595 * NOTE: xflags is passed as a constant, optimizing this inline function! 1596 */ 1597 static void 1598 buf_vlist_add(struct buf *bp, struct bufobj *bo, b_xflags_t xflags) 1599 { 1600 struct bufv *bv; 1601 struct buf *n; 1602 int error; 1603 1604 ASSERT_BO_WLOCKED(bo); 1605 KASSERT((xflags & BX_VNDIRTY) == 0 || (bo->bo_flag & BO_DEAD) == 0, 1606 ("dead bo %p", bo)); 1607 KASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) == 0, 1608 ("buf_vlist_add: Buf %p has existing xflags %d", bp, bp->b_xflags)); 1609 bp->b_xflags |= xflags; 1610 if (xflags & BX_VNDIRTY) 1611 bv = &bo->bo_dirty; 1612 else 1613 bv = &bo->bo_clean; 1614 1615 /* 1616 * Keep the list ordered. Optimize empty list insertion. Assume 1617 * we tend to grow at the tail so lookup_le should usually be cheaper 1618 * than _ge. 1619 */ 1620 if (bv->bv_cnt == 0 || 1621 bp->b_lblkno > TAILQ_LAST(&bv->bv_hd, buflists)->b_lblkno) 1622 TAILQ_INSERT_TAIL(&bv->bv_hd, bp, b_bobufs); 1623 else if ((n = BUF_PCTRIE_LOOKUP_LE(&bv->bv_root, bp->b_lblkno)) == NULL) 1624 TAILQ_INSERT_HEAD(&bv->bv_hd, bp, b_bobufs); 1625 else 1626 TAILQ_INSERT_AFTER(&bv->bv_hd, n, bp, b_bobufs); 1627 error = BUF_PCTRIE_INSERT(&bv->bv_root, bp); 1628 if (error) 1629 panic("buf_vlist_add: Preallocated nodes insufficient."); 1630 bv->bv_cnt++; 1631 } 1632 1633 /* 1634 * Look up a buffer using the buffer tries. 1635 */ 1636 struct buf * 1637 gbincore(struct bufobj *bo, daddr_t lblkno) 1638 { 1639 struct buf *bp; 1640 1641 ASSERT_BO_LOCKED(bo); 1642 bp = BUF_PCTRIE_LOOKUP(&bo->bo_clean.bv_root, lblkno); 1643 if (bp != NULL) 1644 return (bp); 1645 return BUF_PCTRIE_LOOKUP(&bo->bo_dirty.bv_root, lblkno); 1646 } 1647 1648 /* 1649 * Associate a buffer with a vnode. 1650 */ 1651 void 1652 bgetvp(struct vnode *vp, struct buf *bp) 1653 { 1654 struct bufobj *bo; 1655 1656 bo = &vp->v_bufobj; 1657 ASSERT_BO_WLOCKED(bo); 1658 VNASSERT(bp->b_vp == NULL, bp->b_vp, ("bgetvp: not free")); 1659 1660 CTR3(KTR_BUF, "bgetvp(%p) vp %p flags %X", bp, vp, bp->b_flags); 1661 VNASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) == 0, vp, 1662 ("bgetvp: bp already attached! %p", bp)); 1663 1664 vhold(vp); 1665 bp->b_vp = vp; 1666 bp->b_bufobj = bo; 1667 /* 1668 * Insert onto list for new vnode. 1669 */ 1670 buf_vlist_add(bp, bo, BX_VNCLEAN); 1671 } 1672 1673 /* 1674 * Disassociate a buffer from a vnode. 1675 */ 1676 void 1677 brelvp(struct buf *bp) 1678 { 1679 struct bufobj *bo; 1680 struct vnode *vp; 1681 1682 CTR3(KTR_BUF, "brelvp(%p) vp %p flags %X", bp, bp->b_vp, bp->b_flags); 1683 KASSERT(bp->b_vp != NULL, ("brelvp: NULL")); 1684 1685 /* 1686 * Delete from old vnode list, if on one. 1687 */ 1688 vp = bp->b_vp; /* XXX */ 1689 bo = bp->b_bufobj; 1690 BO_LOCK(bo); 1691 if (bp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN)) 1692 buf_vlist_remove(bp); 1693 else 1694 panic("brelvp: Buffer %p not on queue.", bp); 1695 if ((bo->bo_flag & BO_ONWORKLST) && bo->bo_dirty.bv_cnt == 0) { 1696 bo->bo_flag &= ~BO_ONWORKLST; 1697 mtx_lock(&sync_mtx); 1698 LIST_REMOVE(bo, bo_synclist); 1699 syncer_worklist_len--; 1700 mtx_unlock(&sync_mtx); 1701 } 1702 bp->b_vp = NULL; 1703 bp->b_bufobj = NULL; 1704 BO_UNLOCK(bo); 1705 vdrop(vp); 1706 } 1707 1708 /* 1709 * Add an item to the syncer work queue. 1710 */ 1711 static void 1712 vn_syncer_add_to_worklist(struct bufobj *bo, int delay) 1713 { 1714 int slot; 1715 1716 ASSERT_BO_WLOCKED(bo); 1717 1718 mtx_lock(&sync_mtx); 1719 if (bo->bo_flag & BO_ONWORKLST) 1720 LIST_REMOVE(bo, bo_synclist); 1721 else { 1722 bo->bo_flag |= BO_ONWORKLST; 1723 syncer_worklist_len++; 1724 } 1725 1726 if (delay > syncer_maxdelay - 2) 1727 delay = syncer_maxdelay - 2; 1728 slot = (syncer_delayno + delay) & syncer_mask; 1729 1730 LIST_INSERT_HEAD(&syncer_workitem_pending[slot], bo, bo_synclist); 1731 mtx_unlock(&sync_mtx); 1732 } 1733 1734 static int 1735 sysctl_vfs_worklist_len(SYSCTL_HANDLER_ARGS) 1736 { 1737 int error, len; 1738 1739 mtx_lock(&sync_mtx); 1740 len = syncer_worklist_len - sync_vnode_count; 1741 mtx_unlock(&sync_mtx); 1742 error = SYSCTL_OUT(req, &len, sizeof(len)); 1743 return (error); 1744 } 1745 1746 SYSCTL_PROC(_vfs, OID_AUTO, worklist_len, CTLTYPE_INT | CTLFLAG_RD, NULL, 0, 1747 sysctl_vfs_worklist_len, "I", "Syncer thread worklist length"); 1748 1749 static struct proc *updateproc; 1750 static void sched_sync(void); 1751 static struct kproc_desc up_kp = { 1752 "syncer", 1753 sched_sync, 1754 &updateproc 1755 }; 1756 SYSINIT(syncer, SI_SUB_KTHREAD_UPDATE, SI_ORDER_FIRST, kproc_start, &up_kp); 1757 1758 static int 1759 sync_vnode(struct synclist *slp, struct bufobj **bo, struct thread *td) 1760 { 1761 struct vnode *vp; 1762 struct mount *mp; 1763 1764 *bo = LIST_FIRST(slp); 1765 if (*bo == NULL) 1766 return (0); 1767 vp = (*bo)->__bo_vnode; /* XXX */ 1768 if (VOP_ISLOCKED(vp) != 0 || VI_TRYLOCK(vp) == 0) 1769 return (1); 1770 /* 1771 * We use vhold in case the vnode does not 1772 * successfully sync. vhold prevents the vnode from 1773 * going away when we unlock the sync_mtx so that 1774 * we can acquire the vnode interlock. 1775 */ 1776 vholdl(vp); 1777 mtx_unlock(&sync_mtx); 1778 VI_UNLOCK(vp); 1779 if (vn_start_write(vp, &mp, V_NOWAIT) != 0) { 1780 vdrop(vp); 1781 mtx_lock(&sync_mtx); 1782 return (*bo == LIST_FIRST(slp)); 1783 } 1784 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 1785 (void) VOP_FSYNC(vp, MNT_LAZY, td); 1786 VOP_UNLOCK(vp, 0); 1787 vn_finished_write(mp); 1788 BO_LOCK(*bo); 1789 if (((*bo)->bo_flag & BO_ONWORKLST) != 0) { 1790 /* 1791 * Put us back on the worklist. The worklist 1792 * routine will remove us from our current 1793 * position and then add us back in at a later 1794 * position. 1795 */ 1796 vn_syncer_add_to_worklist(*bo, syncdelay); 1797 } 1798 BO_UNLOCK(*bo); 1799 vdrop(vp); 1800 mtx_lock(&sync_mtx); 1801 return (0); 1802 } 1803 1804 static int first_printf = 1; 1805 1806 /* 1807 * System filesystem synchronizer daemon. 1808 */ 1809 static void 1810 sched_sync(void) 1811 { 1812 struct synclist *next, *slp; 1813 struct bufobj *bo; 1814 long starttime; 1815 struct thread *td = curthread; 1816 int last_work_seen; 1817 int net_worklist_len; 1818 int syncer_final_iter; 1819 int error; 1820 1821 last_work_seen = 0; 1822 syncer_final_iter = 0; 1823 syncer_state = SYNCER_RUNNING; 1824 starttime = time_uptime; 1825 td->td_pflags |= TDP_NORUNNINGBUF; 1826 1827 EVENTHANDLER_REGISTER(shutdown_pre_sync, syncer_shutdown, td->td_proc, 1828 SHUTDOWN_PRI_LAST); 1829 1830 mtx_lock(&sync_mtx); 1831 for (;;) { 1832 if (syncer_state == SYNCER_FINAL_DELAY && 1833 syncer_final_iter == 0) { 1834 mtx_unlock(&sync_mtx); 1835 kproc_suspend_check(td->td_proc); 1836 mtx_lock(&sync_mtx); 1837 } 1838 net_worklist_len = syncer_worklist_len - sync_vnode_count; 1839 if (syncer_state != SYNCER_RUNNING && 1840 starttime != time_uptime) { 1841 if (first_printf) { 1842 printf("\nSyncing disks, vnodes remaining..."); 1843 first_printf = 0; 1844 } 1845 printf("%d ", net_worklist_len); 1846 } 1847 starttime = time_uptime; 1848 1849 /* 1850 * Push files whose dirty time has expired. Be careful 1851 * of interrupt race on slp queue. 1852 * 1853 * Skip over empty worklist slots when shutting down. 1854 */ 1855 do { 1856 slp = &syncer_workitem_pending[syncer_delayno]; 1857 syncer_delayno += 1; 1858 if (syncer_delayno == syncer_maxdelay) 1859 syncer_delayno = 0; 1860 next = &syncer_workitem_pending[syncer_delayno]; 1861 /* 1862 * If the worklist has wrapped since the 1863 * it was emptied of all but syncer vnodes, 1864 * switch to the FINAL_DELAY state and run 1865 * for one more second. 1866 */ 1867 if (syncer_state == SYNCER_SHUTTING_DOWN && 1868 net_worklist_len == 0 && 1869 last_work_seen == syncer_delayno) { 1870 syncer_state = SYNCER_FINAL_DELAY; 1871 syncer_final_iter = SYNCER_SHUTDOWN_SPEEDUP; 1872 } 1873 } while (syncer_state != SYNCER_RUNNING && LIST_EMPTY(slp) && 1874 syncer_worklist_len > 0); 1875 1876 /* 1877 * Keep track of the last time there was anything 1878 * on the worklist other than syncer vnodes. 1879 * Return to the SHUTTING_DOWN state if any 1880 * new work appears. 1881 */ 1882 if (net_worklist_len > 0 || syncer_state == SYNCER_RUNNING) 1883 last_work_seen = syncer_delayno; 1884 if (net_worklist_len > 0 && syncer_state == SYNCER_FINAL_DELAY) 1885 syncer_state = SYNCER_SHUTTING_DOWN; 1886 while (!LIST_EMPTY(slp)) { 1887 error = sync_vnode(slp, &bo, td); 1888 if (error == 1) { 1889 LIST_REMOVE(bo, bo_synclist); 1890 LIST_INSERT_HEAD(next, bo, bo_synclist); 1891 continue; 1892 } 1893 1894 if (first_printf == 0) { 1895 /* 1896 * Drop the sync mutex, because some watchdog 1897 * drivers need to sleep while patting 1898 */ 1899 mtx_unlock(&sync_mtx); 1900 wdog_kern_pat(WD_LASTVAL); 1901 mtx_lock(&sync_mtx); 1902 } 1903 1904 } 1905 if (syncer_state == SYNCER_FINAL_DELAY && syncer_final_iter > 0) 1906 syncer_final_iter--; 1907 /* 1908 * The variable rushjob allows the kernel to speed up the 1909 * processing of the filesystem syncer process. A rushjob 1910 * value of N tells the filesystem syncer to process the next 1911 * N seconds worth of work on its queue ASAP. Currently rushjob 1912 * is used by the soft update code to speed up the filesystem 1913 * syncer process when the incore state is getting so far 1914 * ahead of the disk that the kernel memory pool is being 1915 * threatened with exhaustion. 1916 */ 1917 if (rushjob > 0) { 1918 rushjob -= 1; 1919 continue; 1920 } 1921 /* 1922 * Just sleep for a short period of time between 1923 * iterations when shutting down to allow some I/O 1924 * to happen. 1925 * 1926 * If it has taken us less than a second to process the 1927 * current work, then wait. Otherwise start right over 1928 * again. We can still lose time if any single round 1929 * takes more than two seconds, but it does not really 1930 * matter as we are just trying to generally pace the 1931 * filesystem activity. 1932 */ 1933 if (syncer_state != SYNCER_RUNNING || 1934 time_uptime == starttime) { 1935 thread_lock(td); 1936 sched_prio(td, PPAUSE); 1937 thread_unlock(td); 1938 } 1939 if (syncer_state != SYNCER_RUNNING) 1940 cv_timedwait(&sync_wakeup, &sync_mtx, 1941 hz / SYNCER_SHUTDOWN_SPEEDUP); 1942 else if (time_uptime == starttime) 1943 cv_timedwait(&sync_wakeup, &sync_mtx, hz); 1944 } 1945 } 1946 1947 /* 1948 * Request the syncer daemon to speed up its work. 1949 * We never push it to speed up more than half of its 1950 * normal turn time, otherwise it could take over the cpu. 1951 */ 1952 int 1953 speedup_syncer(void) 1954 { 1955 int ret = 0; 1956 1957 mtx_lock(&sync_mtx); 1958 if (rushjob < syncdelay / 2) { 1959 rushjob += 1; 1960 stat_rush_requests += 1; 1961 ret = 1; 1962 } 1963 mtx_unlock(&sync_mtx); 1964 cv_broadcast(&sync_wakeup); 1965 return (ret); 1966 } 1967 1968 /* 1969 * Tell the syncer to speed up its work and run though its work 1970 * list several times, then tell it to shut down. 1971 */ 1972 static void 1973 syncer_shutdown(void *arg, int howto) 1974 { 1975 1976 if (howto & RB_NOSYNC) 1977 return; 1978 mtx_lock(&sync_mtx); 1979 syncer_state = SYNCER_SHUTTING_DOWN; 1980 rushjob = 0; 1981 mtx_unlock(&sync_mtx); 1982 cv_broadcast(&sync_wakeup); 1983 kproc_shutdown(arg, howto); 1984 } 1985 1986 void 1987 syncer_suspend(void) 1988 { 1989 1990 syncer_shutdown(updateproc, 0); 1991 } 1992 1993 void 1994 syncer_resume(void) 1995 { 1996 1997 mtx_lock(&sync_mtx); 1998 first_printf = 1; 1999 syncer_state = SYNCER_RUNNING; 2000 mtx_unlock(&sync_mtx); 2001 cv_broadcast(&sync_wakeup); 2002 kproc_resume(updateproc); 2003 } 2004 2005 /* 2006 * Reassign a buffer from one vnode to another. 2007 * Used to assign file specific control information 2008 * (indirect blocks) to the vnode to which they belong. 2009 */ 2010 void 2011 reassignbuf(struct buf *bp) 2012 { 2013 struct vnode *vp; 2014 struct bufobj *bo; 2015 int delay; 2016 #ifdef INVARIANTS 2017 struct bufv *bv; 2018 #endif 2019 2020 vp = bp->b_vp; 2021 bo = bp->b_bufobj; 2022 ++reassignbufcalls; 2023 2024 CTR3(KTR_BUF, "reassignbuf(%p) vp %p flags %X", 2025 bp, bp->b_vp, bp->b_flags); 2026 /* 2027 * B_PAGING flagged buffers cannot be reassigned because their vp 2028 * is not fully linked in. 2029 */ 2030 if (bp->b_flags & B_PAGING) 2031 panic("cannot reassign paging buffer"); 2032 2033 /* 2034 * Delete from old vnode list, if on one. 2035 */ 2036 BO_LOCK(bo); 2037 if (bp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN)) 2038 buf_vlist_remove(bp); 2039 else 2040 panic("reassignbuf: Buffer %p not on queue.", bp); 2041 /* 2042 * If dirty, put on list of dirty buffers; otherwise insert onto list 2043 * of clean buffers. 2044 */ 2045 if (bp->b_flags & B_DELWRI) { 2046 if ((bo->bo_flag & BO_ONWORKLST) == 0) { 2047 switch (vp->v_type) { 2048 case VDIR: 2049 delay = dirdelay; 2050 break; 2051 case VCHR: 2052 delay = metadelay; 2053 break; 2054 default: 2055 delay = filedelay; 2056 } 2057 vn_syncer_add_to_worklist(bo, delay); 2058 } 2059 buf_vlist_add(bp, bo, BX_VNDIRTY); 2060 } else { 2061 buf_vlist_add(bp, bo, BX_VNCLEAN); 2062 2063 if ((bo->bo_flag & BO_ONWORKLST) && bo->bo_dirty.bv_cnt == 0) { 2064 mtx_lock(&sync_mtx); 2065 LIST_REMOVE(bo, bo_synclist); 2066 syncer_worklist_len--; 2067 mtx_unlock(&sync_mtx); 2068 bo->bo_flag &= ~BO_ONWORKLST; 2069 } 2070 } 2071 #ifdef INVARIANTS 2072 bv = &bo->bo_clean; 2073 bp = TAILQ_FIRST(&bv->bv_hd); 2074 KASSERT(bp == NULL || bp->b_bufobj == bo, 2075 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 2076 bp = TAILQ_LAST(&bv->bv_hd, buflists); 2077 KASSERT(bp == NULL || bp->b_bufobj == bo, 2078 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 2079 bv = &bo->bo_dirty; 2080 bp = TAILQ_FIRST(&bv->bv_hd); 2081 KASSERT(bp == NULL || bp->b_bufobj == bo, 2082 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 2083 bp = TAILQ_LAST(&bv->bv_hd, buflists); 2084 KASSERT(bp == NULL || bp->b_bufobj == bo, 2085 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 2086 #endif 2087 BO_UNLOCK(bo); 2088 } 2089 2090 /* 2091 * A temporary hack until refcount_* APIs are sorted out. 2092 */ 2093 static __inline int 2094 vfs_refcount_acquire_if_not_zero(volatile u_int *count) 2095 { 2096 u_int old; 2097 2098 for (;;) { 2099 old = *count; 2100 if (old == 0) 2101 return (0); 2102 if (atomic_cmpset_int(count, old, old + 1)) 2103 return (1); 2104 } 2105 } 2106 2107 static __inline int 2108 vfs_refcount_release_if_not_last(volatile u_int *count) 2109 { 2110 u_int old; 2111 2112 for (;;) { 2113 old = *count; 2114 if (old == 1) 2115 return (0); 2116 if (atomic_cmpset_int(count, old, old - 1)) 2117 return (1); 2118 } 2119 } 2120 2121 static void 2122 v_init_counters(struct vnode *vp) 2123 { 2124 2125 VNASSERT(vp->v_type == VNON && vp->v_data == NULL && vp->v_iflag == 0, 2126 vp, ("%s called for an initialized vnode", __FUNCTION__)); 2127 ASSERT_VI_UNLOCKED(vp, __FUNCTION__); 2128 2129 refcount_init(&vp->v_holdcnt, 1); 2130 refcount_init(&vp->v_usecount, 1); 2131 } 2132 2133 /* 2134 * Increment the use and hold counts on the vnode, taking care to reference 2135 * the driver's usecount if this is a chardev. The _vhold() will remove 2136 * the vnode from the free list if it is presently free. 2137 */ 2138 static void 2139 v_incr_usecount(struct vnode *vp) 2140 { 2141 2142 ASSERT_VI_UNLOCKED(vp, __func__); 2143 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2144 2145 if (vp->v_type == VCHR) { 2146 VI_LOCK(vp); 2147 _vhold(vp, true); 2148 if (vp->v_iflag & VI_OWEINACT) { 2149 VNASSERT(vp->v_usecount == 0, vp, 2150 ("vnode with usecount and VI_OWEINACT set")); 2151 vp->v_iflag &= ~VI_OWEINACT; 2152 } 2153 refcount_acquire(&vp->v_usecount); 2154 v_incr_devcount(vp); 2155 VI_UNLOCK(vp); 2156 return; 2157 } 2158 2159 _vhold(vp, false); 2160 if (vfs_refcount_acquire_if_not_zero(&vp->v_usecount)) { 2161 VNASSERT((vp->v_iflag & VI_OWEINACT) == 0, vp, 2162 ("vnode with usecount and VI_OWEINACT set")); 2163 } else { 2164 VI_LOCK(vp); 2165 if (vp->v_iflag & VI_OWEINACT) 2166 vp->v_iflag &= ~VI_OWEINACT; 2167 refcount_acquire(&vp->v_usecount); 2168 VI_UNLOCK(vp); 2169 } 2170 } 2171 2172 /* 2173 * Increment si_usecount of the associated device, if any. 2174 */ 2175 static void 2176 v_incr_devcount(struct vnode *vp) 2177 { 2178 2179 ASSERT_VI_LOCKED(vp, __FUNCTION__); 2180 if (vp->v_type == VCHR && vp->v_rdev != NULL) { 2181 dev_lock(); 2182 vp->v_rdev->si_usecount++; 2183 dev_unlock(); 2184 } 2185 } 2186 2187 /* 2188 * Decrement si_usecount of the associated device, if any. 2189 */ 2190 static void 2191 v_decr_devcount(struct vnode *vp) 2192 { 2193 2194 ASSERT_VI_LOCKED(vp, __FUNCTION__); 2195 if (vp->v_type == VCHR && vp->v_rdev != NULL) { 2196 dev_lock(); 2197 vp->v_rdev->si_usecount--; 2198 dev_unlock(); 2199 } 2200 } 2201 2202 /* 2203 * Grab a particular vnode from the free list, increment its 2204 * reference count and lock it. VI_DOOMED is set if the vnode 2205 * is being destroyed. Only callers who specify LK_RETRY will 2206 * see doomed vnodes. If inactive processing was delayed in 2207 * vput try to do it here. 2208 * 2209 * Notes on lockless counter manipulation: 2210 * _vhold, vputx and other routines make various decisions based 2211 * on either holdcnt or usecount being 0. As long as either contuner 2212 * is not transitioning 0->1 nor 1->0, the manipulation can be done 2213 * with atomic operations. Otherwise the interlock is taken. 2214 */ 2215 int 2216 vget(struct vnode *vp, int flags, struct thread *td) 2217 { 2218 int error, oweinact; 2219 2220 VNASSERT((flags & LK_TYPE_MASK) != 0, vp, 2221 ("vget: invalid lock operation")); 2222 2223 if ((flags & LK_INTERLOCK) != 0) 2224 ASSERT_VI_LOCKED(vp, __func__); 2225 else 2226 ASSERT_VI_UNLOCKED(vp, __func__); 2227 if ((flags & LK_VNHELD) != 0) 2228 VNASSERT((vp->v_holdcnt > 0), vp, 2229 ("vget: LK_VNHELD passed but vnode not held")); 2230 2231 CTR3(KTR_VFS, "%s: vp %p with flags %d", __func__, vp, flags); 2232 2233 if ((flags & LK_VNHELD) == 0) 2234 _vhold(vp, (flags & LK_INTERLOCK) != 0); 2235 2236 if ((error = vn_lock(vp, flags)) != 0) { 2237 vdrop(vp); 2238 CTR2(KTR_VFS, "%s: impossible to lock vnode %p", __func__, 2239 vp); 2240 return (error); 2241 } 2242 if (vp->v_iflag & VI_DOOMED && (flags & LK_RETRY) == 0) 2243 panic("vget: vn_lock failed to return ENOENT\n"); 2244 /* 2245 * We don't guarantee that any particular close will 2246 * trigger inactive processing so just make a best effort 2247 * here at preventing a reference to a removed file. If 2248 * we don't succeed no harm is done. 2249 * 2250 * Upgrade our holdcnt to a usecount. 2251 */ 2252 if (vp->v_type != VCHR && 2253 vfs_refcount_acquire_if_not_zero(&vp->v_usecount)) { 2254 VNASSERT((vp->v_iflag & VI_OWEINACT) == 0, vp, 2255 ("vnode with usecount and VI_OWEINACT set")); 2256 } else { 2257 VI_LOCK(vp); 2258 if ((vp->v_iflag & VI_OWEINACT) == 0) { 2259 oweinact = 0; 2260 } else { 2261 oweinact = 1; 2262 vp->v_iflag &= ~VI_OWEINACT; 2263 } 2264 refcount_acquire(&vp->v_usecount); 2265 v_incr_devcount(vp); 2266 if (oweinact && VOP_ISLOCKED(vp) == LK_EXCLUSIVE && 2267 (flags & LK_NOWAIT) == 0) 2268 vinactive(vp, td); 2269 VI_UNLOCK(vp); 2270 } 2271 return (0); 2272 } 2273 2274 /* 2275 * Increase the reference count of a vnode. 2276 */ 2277 void 2278 vref(struct vnode *vp) 2279 { 2280 2281 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2282 v_incr_usecount(vp); 2283 } 2284 2285 /* 2286 * Return reference count of a vnode. 2287 * 2288 * The results of this call are only guaranteed when some mechanism is used to 2289 * stop other processes from gaining references to the vnode. This may be the 2290 * case if the caller holds the only reference. This is also useful when stale 2291 * data is acceptable as race conditions may be accounted for by some other 2292 * means. 2293 */ 2294 int 2295 vrefcnt(struct vnode *vp) 2296 { 2297 2298 return (vp->v_usecount); 2299 } 2300 2301 #define VPUTX_VRELE 1 2302 #define VPUTX_VPUT 2 2303 #define VPUTX_VUNREF 3 2304 2305 /* 2306 * Decrement the use and hold counts for a vnode. 2307 * 2308 * See an explanation near vget() as to why atomic operation is safe. 2309 */ 2310 static void 2311 vputx(struct vnode *vp, int func) 2312 { 2313 int error; 2314 2315 KASSERT(vp != NULL, ("vputx: null vp")); 2316 if (func == VPUTX_VUNREF) 2317 ASSERT_VOP_LOCKED(vp, "vunref"); 2318 else if (func == VPUTX_VPUT) 2319 ASSERT_VOP_LOCKED(vp, "vput"); 2320 else 2321 KASSERT(func == VPUTX_VRELE, ("vputx: wrong func")); 2322 ASSERT_VI_UNLOCKED(vp, __func__); 2323 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2324 2325 if (vp->v_type != VCHR && 2326 vfs_refcount_release_if_not_last(&vp->v_usecount)) { 2327 if (func == VPUTX_VPUT) 2328 VOP_UNLOCK(vp, 0); 2329 vdrop(vp); 2330 return; 2331 } 2332 2333 VI_LOCK(vp); 2334 2335 /* 2336 * We want to hold the vnode until the inactive finishes to 2337 * prevent vgone() races. We drop the use count here and the 2338 * hold count below when we're done. 2339 */ 2340 if (!refcount_release(&vp->v_usecount) || 2341 (vp->v_iflag & VI_DOINGINACT)) { 2342 if (func == VPUTX_VPUT) 2343 VOP_UNLOCK(vp, 0); 2344 v_decr_devcount(vp); 2345 vdropl(vp); 2346 return; 2347 } 2348 2349 v_decr_devcount(vp); 2350 2351 error = 0; 2352 2353 if (vp->v_usecount != 0) { 2354 vprint("vputx: usecount not zero", vp); 2355 panic("vputx: usecount not zero"); 2356 } 2357 2358 CTR2(KTR_VFS, "%s: return vnode %p to the freelist", __func__, vp); 2359 2360 /* 2361 * We must call VOP_INACTIVE with the node locked. Mark 2362 * as VI_DOINGINACT to avoid recursion. 2363 */ 2364 vp->v_iflag |= VI_OWEINACT; 2365 switch (func) { 2366 case VPUTX_VRELE: 2367 error = vn_lock(vp, LK_EXCLUSIVE | LK_INTERLOCK); 2368 VI_LOCK(vp); 2369 break; 2370 case VPUTX_VPUT: 2371 if (VOP_ISLOCKED(vp) != LK_EXCLUSIVE) { 2372 error = VOP_LOCK(vp, LK_UPGRADE | LK_INTERLOCK | 2373 LK_NOWAIT); 2374 VI_LOCK(vp); 2375 } 2376 break; 2377 case VPUTX_VUNREF: 2378 if (VOP_ISLOCKED(vp) != LK_EXCLUSIVE) { 2379 error = VOP_LOCK(vp, LK_TRYUPGRADE | LK_INTERLOCK); 2380 VI_LOCK(vp); 2381 } 2382 break; 2383 } 2384 VNASSERT(vp->v_usecount == 0 || (vp->v_iflag & VI_OWEINACT) == 0, vp, 2385 ("vnode with usecount and VI_OWEINACT set")); 2386 if (error == 0) { 2387 if (vp->v_iflag & VI_OWEINACT) 2388 vinactive(vp, curthread); 2389 if (func != VPUTX_VUNREF) 2390 VOP_UNLOCK(vp, 0); 2391 } 2392 vdropl(vp); 2393 } 2394 2395 /* 2396 * Vnode put/release. 2397 * If count drops to zero, call inactive routine and return to freelist. 2398 */ 2399 void 2400 vrele(struct vnode *vp) 2401 { 2402 2403 vputx(vp, VPUTX_VRELE); 2404 } 2405 2406 /* 2407 * Release an already locked vnode. This give the same effects as 2408 * unlock+vrele(), but takes less time and avoids releasing and 2409 * re-aquiring the lock (as vrele() acquires the lock internally.) 2410 */ 2411 void 2412 vput(struct vnode *vp) 2413 { 2414 2415 vputx(vp, VPUTX_VPUT); 2416 } 2417 2418 /* 2419 * Release an exclusively locked vnode. Do not unlock the vnode lock. 2420 */ 2421 void 2422 vunref(struct vnode *vp) 2423 { 2424 2425 vputx(vp, VPUTX_VUNREF); 2426 } 2427 2428 /* 2429 * Increase the hold count and activate if this is the first reference. 2430 */ 2431 void 2432 _vhold(struct vnode *vp, bool locked) 2433 { 2434 struct mount *mp; 2435 2436 if (locked) 2437 ASSERT_VI_LOCKED(vp, __func__); 2438 else 2439 ASSERT_VI_UNLOCKED(vp, __func__); 2440 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2441 if (!locked && vfs_refcount_acquire_if_not_zero(&vp->v_holdcnt)) { 2442 VNASSERT((vp->v_iflag & VI_FREE) == 0, vp, 2443 ("_vhold: vnode with holdcnt is free")); 2444 return; 2445 } 2446 2447 if (!locked) 2448 VI_LOCK(vp); 2449 if ((vp->v_iflag & VI_FREE) == 0) { 2450 refcount_acquire(&vp->v_holdcnt); 2451 if (!locked) 2452 VI_UNLOCK(vp); 2453 return; 2454 } 2455 VNASSERT(vp->v_holdcnt == 0, vp, 2456 ("%s: wrong hold count", __func__)); 2457 VNASSERT(vp->v_op != NULL, vp, 2458 ("%s: vnode already reclaimed.", __func__)); 2459 /* 2460 * Remove a vnode from the free list, mark it as in use, 2461 * and put it on the active list. 2462 */ 2463 mtx_lock(&vnode_free_list_mtx); 2464 TAILQ_REMOVE(&vnode_free_list, vp, v_actfreelist); 2465 freevnodes--; 2466 vp->v_iflag &= ~(VI_FREE|VI_AGE); 2467 KASSERT((vp->v_iflag & VI_ACTIVE) == 0, 2468 ("Activating already active vnode")); 2469 vp->v_iflag |= VI_ACTIVE; 2470 mp = vp->v_mount; 2471 TAILQ_INSERT_HEAD(&mp->mnt_activevnodelist, vp, v_actfreelist); 2472 mp->mnt_activevnodelistsize++; 2473 mtx_unlock(&vnode_free_list_mtx); 2474 refcount_acquire(&vp->v_holdcnt); 2475 if (!locked) 2476 VI_UNLOCK(vp); 2477 } 2478 2479 /* 2480 * Drop the hold count of the vnode. If this is the last reference to 2481 * the vnode we place it on the free list unless it has been vgone'd 2482 * (marked VI_DOOMED) in which case we will free it. 2483 */ 2484 void 2485 _vdrop(struct vnode *vp, bool locked) 2486 { 2487 struct bufobj *bo; 2488 struct mount *mp; 2489 int active; 2490 2491 if (locked) 2492 ASSERT_VI_LOCKED(vp, __func__); 2493 else 2494 ASSERT_VI_UNLOCKED(vp, __func__); 2495 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2496 if ((int)vp->v_holdcnt <= 0) 2497 panic("vdrop: holdcnt %d", vp->v_holdcnt); 2498 if (vfs_refcount_release_if_not_last(&vp->v_holdcnt)) { 2499 if (locked) 2500 VI_UNLOCK(vp); 2501 return; 2502 } 2503 2504 if (!locked) 2505 VI_LOCK(vp); 2506 if (refcount_release(&vp->v_holdcnt) == 0) { 2507 VI_UNLOCK(vp); 2508 return; 2509 } 2510 if ((vp->v_iflag & VI_DOOMED) == 0) { 2511 /* 2512 * Mark a vnode as free: remove it from its active list 2513 * and put it up for recycling on the freelist. 2514 */ 2515 VNASSERT(vp->v_op != NULL, vp, 2516 ("vdropl: vnode already reclaimed.")); 2517 VNASSERT((vp->v_iflag & VI_FREE) == 0, vp, 2518 ("vnode already free")); 2519 VNASSERT(vp->v_holdcnt == 0, vp, 2520 ("vdropl: freeing when we shouldn't")); 2521 active = vp->v_iflag & VI_ACTIVE; 2522 if ((vp->v_iflag & VI_OWEINACT) == 0) { 2523 vp->v_iflag &= ~VI_ACTIVE; 2524 mp = vp->v_mount; 2525 mtx_lock(&vnode_free_list_mtx); 2526 if (active) { 2527 TAILQ_REMOVE(&mp->mnt_activevnodelist, vp, 2528 v_actfreelist); 2529 mp->mnt_activevnodelistsize--; 2530 } 2531 if (vp->v_iflag & VI_AGE) { 2532 TAILQ_INSERT_HEAD(&vnode_free_list, vp, 2533 v_actfreelist); 2534 } else { 2535 TAILQ_INSERT_TAIL(&vnode_free_list, vp, 2536 v_actfreelist); 2537 } 2538 freevnodes++; 2539 vp->v_iflag &= ~VI_AGE; 2540 vp->v_iflag |= VI_FREE; 2541 mtx_unlock(&vnode_free_list_mtx); 2542 } else { 2543 atomic_add_long(&free_owe_inact, 1); 2544 } 2545 VI_UNLOCK(vp); 2546 return; 2547 } 2548 /* 2549 * The vnode has been marked for destruction, so free it. 2550 */ 2551 CTR2(KTR_VFS, "%s: destroying the vnode %p", __func__, vp); 2552 atomic_subtract_long(&numvnodes, 1); 2553 bo = &vp->v_bufobj; 2554 VNASSERT((vp->v_iflag & VI_FREE) == 0, vp, 2555 ("cleaned vnode still on the free list.")); 2556 VNASSERT(vp->v_data == NULL, vp, ("cleaned vnode isn't")); 2557 VNASSERT(vp->v_holdcnt == 0, vp, ("Non-zero hold count")); 2558 VNASSERT(vp->v_usecount == 0, vp, ("Non-zero use count")); 2559 VNASSERT(vp->v_writecount == 0, vp, ("Non-zero write count")); 2560 VNASSERT(bo->bo_numoutput == 0, vp, ("Clean vnode has pending I/O's")); 2561 VNASSERT(bo->bo_clean.bv_cnt == 0, vp, ("cleanbufcnt not 0")); 2562 VNASSERT(pctrie_is_empty(&bo->bo_clean.bv_root), vp, 2563 ("clean blk trie not empty")); 2564 VNASSERT(bo->bo_dirty.bv_cnt == 0, vp, ("dirtybufcnt not 0")); 2565 VNASSERT(pctrie_is_empty(&bo->bo_dirty.bv_root), vp, 2566 ("dirty blk trie not empty")); 2567 VNASSERT(TAILQ_EMPTY(&vp->v_cache_dst), vp, ("vp has namecache dst")); 2568 VNASSERT(LIST_EMPTY(&vp->v_cache_src), vp, ("vp has namecache src")); 2569 VNASSERT(vp->v_cache_dd == NULL, vp, ("vp has namecache for ..")); 2570 VI_UNLOCK(vp); 2571 #ifdef MAC 2572 mac_vnode_destroy(vp); 2573 #endif 2574 if (vp->v_pollinfo != NULL) 2575 destroy_vpollinfo(vp->v_pollinfo); 2576 #ifdef INVARIANTS 2577 /* XXX Elsewhere we detect an already freed vnode via NULL v_op. */ 2578 vp->v_op = NULL; 2579 #endif 2580 rangelock_destroy(&vp->v_rl); 2581 lockdestroy(vp->v_vnlock); 2582 mtx_destroy(&vp->v_interlock); 2583 rw_destroy(BO_LOCKPTR(bo)); 2584 uma_zfree(vnode_zone, vp); 2585 } 2586 2587 /* 2588 * Call VOP_INACTIVE on the vnode and manage the DOINGINACT and OWEINACT 2589 * flags. DOINGINACT prevents us from recursing in calls to vinactive. 2590 * OWEINACT tracks whether a vnode missed a call to inactive due to a 2591 * failed lock upgrade. 2592 */ 2593 void 2594 vinactive(struct vnode *vp, struct thread *td) 2595 { 2596 struct vm_object *obj; 2597 2598 ASSERT_VOP_ELOCKED(vp, "vinactive"); 2599 ASSERT_VI_LOCKED(vp, "vinactive"); 2600 VNASSERT((vp->v_iflag & VI_DOINGINACT) == 0, vp, 2601 ("vinactive: recursed on VI_DOINGINACT")); 2602 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2603 vp->v_iflag |= VI_DOINGINACT; 2604 vp->v_iflag &= ~VI_OWEINACT; 2605 VI_UNLOCK(vp); 2606 /* 2607 * Before moving off the active list, we must be sure that any 2608 * modified pages are on the vnode's dirty list since these will 2609 * no longer be checked once the vnode is on the inactive list. 2610 * Because the vnode vm object keeps a hold reference on the vnode 2611 * if there is at least one resident non-cached page, the vnode 2612 * cannot leave the active list without the page cleanup done. 2613 */ 2614 obj = vp->v_object; 2615 if (obj != NULL && (obj->flags & OBJ_MIGHTBEDIRTY) != 0) { 2616 VM_OBJECT_WLOCK(obj); 2617 vm_object_page_clean(obj, 0, 0, OBJPC_NOSYNC); 2618 VM_OBJECT_WUNLOCK(obj); 2619 } 2620 VOP_INACTIVE(vp, td); 2621 VI_LOCK(vp); 2622 VNASSERT(vp->v_iflag & VI_DOINGINACT, vp, 2623 ("vinactive: lost VI_DOINGINACT")); 2624 vp->v_iflag &= ~VI_DOINGINACT; 2625 } 2626 2627 /* 2628 * Remove any vnodes in the vnode table belonging to mount point mp. 2629 * 2630 * If FORCECLOSE is not specified, there should not be any active ones, 2631 * return error if any are found (nb: this is a user error, not a 2632 * system error). If FORCECLOSE is specified, detach any active vnodes 2633 * that are found. 2634 * 2635 * If WRITECLOSE is set, only flush out regular file vnodes open for 2636 * writing. 2637 * 2638 * SKIPSYSTEM causes any vnodes marked VV_SYSTEM to be skipped. 2639 * 2640 * `rootrefs' specifies the base reference count for the root vnode 2641 * of this filesystem. The root vnode is considered busy if its 2642 * v_usecount exceeds this value. On a successful return, vflush(, td) 2643 * will call vrele() on the root vnode exactly rootrefs times. 2644 * If the SKIPSYSTEM or WRITECLOSE flags are specified, rootrefs must 2645 * be zero. 2646 */ 2647 #ifdef DIAGNOSTIC 2648 static int busyprt = 0; /* print out busy vnodes */ 2649 SYSCTL_INT(_debug, OID_AUTO, busyprt, CTLFLAG_RW, &busyprt, 0, "Print out busy vnodes"); 2650 #endif 2651 2652 int 2653 vflush(struct mount *mp, int rootrefs, int flags, struct thread *td) 2654 { 2655 struct vnode *vp, *mvp, *rootvp = NULL; 2656 struct vattr vattr; 2657 int busy = 0, error; 2658 2659 CTR4(KTR_VFS, "%s: mp %p with rootrefs %d and flags %d", __func__, mp, 2660 rootrefs, flags); 2661 if (rootrefs > 0) { 2662 KASSERT((flags & (SKIPSYSTEM | WRITECLOSE)) == 0, 2663 ("vflush: bad args")); 2664 /* 2665 * Get the filesystem root vnode. We can vput() it 2666 * immediately, since with rootrefs > 0, it won't go away. 2667 */ 2668 if ((error = VFS_ROOT(mp, LK_EXCLUSIVE, &rootvp)) != 0) { 2669 CTR2(KTR_VFS, "%s: vfs_root lookup failed with %d", 2670 __func__, error); 2671 return (error); 2672 } 2673 vput(rootvp); 2674 } 2675 loop: 2676 MNT_VNODE_FOREACH_ALL(vp, mp, mvp) { 2677 vholdl(vp); 2678 error = vn_lock(vp, LK_INTERLOCK | LK_EXCLUSIVE); 2679 if (error) { 2680 vdrop(vp); 2681 MNT_VNODE_FOREACH_ALL_ABORT(mp, mvp); 2682 goto loop; 2683 } 2684 /* 2685 * Skip over a vnodes marked VV_SYSTEM. 2686 */ 2687 if ((flags & SKIPSYSTEM) && (vp->v_vflag & VV_SYSTEM)) { 2688 VOP_UNLOCK(vp, 0); 2689 vdrop(vp); 2690 continue; 2691 } 2692 /* 2693 * If WRITECLOSE is set, flush out unlinked but still open 2694 * files (even if open only for reading) and regular file 2695 * vnodes open for writing. 2696 */ 2697 if (flags & WRITECLOSE) { 2698 if (vp->v_object != NULL) { 2699 VM_OBJECT_WLOCK(vp->v_object); 2700 vm_object_page_clean(vp->v_object, 0, 0, 0); 2701 VM_OBJECT_WUNLOCK(vp->v_object); 2702 } 2703 error = VOP_FSYNC(vp, MNT_WAIT, td); 2704 if (error != 0) { 2705 VOP_UNLOCK(vp, 0); 2706 vdrop(vp); 2707 MNT_VNODE_FOREACH_ALL_ABORT(mp, mvp); 2708 return (error); 2709 } 2710 error = VOP_GETATTR(vp, &vattr, td->td_ucred); 2711 VI_LOCK(vp); 2712 2713 if ((vp->v_type == VNON || 2714 (error == 0 && vattr.va_nlink > 0)) && 2715 (vp->v_writecount == 0 || vp->v_type != VREG)) { 2716 VOP_UNLOCK(vp, 0); 2717 vdropl(vp); 2718 continue; 2719 } 2720 } else 2721 VI_LOCK(vp); 2722 /* 2723 * With v_usecount == 0, all we need to do is clear out the 2724 * vnode data structures and we are done. 2725 * 2726 * If FORCECLOSE is set, forcibly close the vnode. 2727 */ 2728 if (vp->v_usecount == 0 || (flags & FORCECLOSE)) { 2729 vgonel(vp); 2730 } else { 2731 busy++; 2732 #ifdef DIAGNOSTIC 2733 if (busyprt) 2734 vprint("vflush: busy vnode", vp); 2735 #endif 2736 } 2737 VOP_UNLOCK(vp, 0); 2738 vdropl(vp); 2739 } 2740 if (rootrefs > 0 && (flags & FORCECLOSE) == 0) { 2741 /* 2742 * If just the root vnode is busy, and if its refcount 2743 * is equal to `rootrefs', then go ahead and kill it. 2744 */ 2745 VI_LOCK(rootvp); 2746 KASSERT(busy > 0, ("vflush: not busy")); 2747 VNASSERT(rootvp->v_usecount >= rootrefs, rootvp, 2748 ("vflush: usecount %d < rootrefs %d", 2749 rootvp->v_usecount, rootrefs)); 2750 if (busy == 1 && rootvp->v_usecount == rootrefs) { 2751 VOP_LOCK(rootvp, LK_EXCLUSIVE|LK_INTERLOCK); 2752 vgone(rootvp); 2753 VOP_UNLOCK(rootvp, 0); 2754 busy = 0; 2755 } else 2756 VI_UNLOCK(rootvp); 2757 } 2758 if (busy) { 2759 CTR2(KTR_VFS, "%s: failing as %d vnodes are busy", __func__, 2760 busy); 2761 return (EBUSY); 2762 } 2763 for (; rootrefs > 0; rootrefs--) 2764 vrele(rootvp); 2765 return (0); 2766 } 2767 2768 /* 2769 * Recycle an unused vnode to the front of the free list. 2770 */ 2771 int 2772 vrecycle(struct vnode *vp) 2773 { 2774 int recycled; 2775 2776 ASSERT_VOP_ELOCKED(vp, "vrecycle"); 2777 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2778 recycled = 0; 2779 VI_LOCK(vp); 2780 if (vp->v_usecount == 0) { 2781 recycled = 1; 2782 vgonel(vp); 2783 } 2784 VI_UNLOCK(vp); 2785 return (recycled); 2786 } 2787 2788 /* 2789 * Eliminate all activity associated with a vnode 2790 * in preparation for reuse. 2791 */ 2792 void 2793 vgone(struct vnode *vp) 2794 { 2795 VI_LOCK(vp); 2796 vgonel(vp); 2797 VI_UNLOCK(vp); 2798 } 2799 2800 static void 2801 notify_lowervp_vfs_dummy(struct mount *mp __unused, 2802 struct vnode *lowervp __unused) 2803 { 2804 } 2805 2806 /* 2807 * Notify upper mounts about reclaimed or unlinked vnode. 2808 */ 2809 void 2810 vfs_notify_upper(struct vnode *vp, int event) 2811 { 2812 static struct vfsops vgonel_vfsops = { 2813 .vfs_reclaim_lowervp = notify_lowervp_vfs_dummy, 2814 .vfs_unlink_lowervp = notify_lowervp_vfs_dummy, 2815 }; 2816 struct mount *mp, *ump, *mmp; 2817 2818 mp = vp->v_mount; 2819 if (mp == NULL) 2820 return; 2821 2822 MNT_ILOCK(mp); 2823 if (TAILQ_EMPTY(&mp->mnt_uppers)) 2824 goto unlock; 2825 MNT_IUNLOCK(mp); 2826 mmp = malloc(sizeof(struct mount), M_TEMP, M_WAITOK | M_ZERO); 2827 mmp->mnt_op = &vgonel_vfsops; 2828 mmp->mnt_kern_flag |= MNTK_MARKER; 2829 MNT_ILOCK(mp); 2830 mp->mnt_kern_flag |= MNTK_VGONE_UPPER; 2831 for (ump = TAILQ_FIRST(&mp->mnt_uppers); ump != NULL;) { 2832 if ((ump->mnt_kern_flag & MNTK_MARKER) != 0) { 2833 ump = TAILQ_NEXT(ump, mnt_upper_link); 2834 continue; 2835 } 2836 TAILQ_INSERT_AFTER(&mp->mnt_uppers, ump, mmp, mnt_upper_link); 2837 MNT_IUNLOCK(mp); 2838 switch (event) { 2839 case VFS_NOTIFY_UPPER_RECLAIM: 2840 VFS_RECLAIM_LOWERVP(ump, vp); 2841 break; 2842 case VFS_NOTIFY_UPPER_UNLINK: 2843 VFS_UNLINK_LOWERVP(ump, vp); 2844 break; 2845 default: 2846 KASSERT(0, ("invalid event %d", event)); 2847 break; 2848 } 2849 MNT_ILOCK(mp); 2850 ump = TAILQ_NEXT(mmp, mnt_upper_link); 2851 TAILQ_REMOVE(&mp->mnt_uppers, mmp, mnt_upper_link); 2852 } 2853 free(mmp, M_TEMP); 2854 mp->mnt_kern_flag &= ~MNTK_VGONE_UPPER; 2855 if ((mp->mnt_kern_flag & MNTK_VGONE_WAITER) != 0) { 2856 mp->mnt_kern_flag &= ~MNTK_VGONE_WAITER; 2857 wakeup(&mp->mnt_uppers); 2858 } 2859 unlock: 2860 MNT_IUNLOCK(mp); 2861 } 2862 2863 /* 2864 * vgone, with the vp interlock held. 2865 */ 2866 static void 2867 vgonel(struct vnode *vp) 2868 { 2869 struct thread *td; 2870 int oweinact; 2871 int active; 2872 struct mount *mp; 2873 2874 ASSERT_VOP_ELOCKED(vp, "vgonel"); 2875 ASSERT_VI_LOCKED(vp, "vgonel"); 2876 VNASSERT(vp->v_holdcnt, vp, 2877 ("vgonel: vp %p has no reference.", vp)); 2878 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2879 td = curthread; 2880 2881 /* 2882 * Don't vgonel if we're already doomed. 2883 */ 2884 if (vp->v_iflag & VI_DOOMED) 2885 return; 2886 vp->v_iflag |= VI_DOOMED; 2887 2888 /* 2889 * Check to see if the vnode is in use. If so, we have to call 2890 * VOP_CLOSE() and VOP_INACTIVE(). 2891 */ 2892 active = vp->v_usecount; 2893 oweinact = (vp->v_iflag & VI_OWEINACT); 2894 VI_UNLOCK(vp); 2895 vfs_notify_upper(vp, VFS_NOTIFY_UPPER_RECLAIM); 2896 2897 /* 2898 * If purging an active vnode, it must be closed and 2899 * deactivated before being reclaimed. 2900 */ 2901 if (active) 2902 VOP_CLOSE(vp, FNONBLOCK, NOCRED, td); 2903 if (oweinact || active) { 2904 VI_LOCK(vp); 2905 if ((vp->v_iflag & VI_DOINGINACT) == 0) 2906 vinactive(vp, td); 2907 VI_UNLOCK(vp); 2908 } 2909 if (vp->v_type == VSOCK) 2910 vfs_unp_reclaim(vp); 2911 2912 /* 2913 * Clean out any buffers associated with the vnode. 2914 * If the flush fails, just toss the buffers. 2915 */ 2916 mp = NULL; 2917 if (!TAILQ_EMPTY(&vp->v_bufobj.bo_dirty.bv_hd)) 2918 (void) vn_start_secondary_write(vp, &mp, V_WAIT); 2919 if (vinvalbuf(vp, V_SAVE, 0, 0) != 0) { 2920 while (vinvalbuf(vp, 0, 0, 0) != 0) 2921 ; 2922 } 2923 2924 BO_LOCK(&vp->v_bufobj); 2925 KASSERT(TAILQ_EMPTY(&vp->v_bufobj.bo_dirty.bv_hd) && 2926 vp->v_bufobj.bo_dirty.bv_cnt == 0 && 2927 TAILQ_EMPTY(&vp->v_bufobj.bo_clean.bv_hd) && 2928 vp->v_bufobj.bo_clean.bv_cnt == 0, 2929 ("vp %p bufobj not invalidated", vp)); 2930 vp->v_bufobj.bo_flag |= BO_DEAD; 2931 BO_UNLOCK(&vp->v_bufobj); 2932 2933 /* 2934 * Reclaim the vnode. 2935 */ 2936 if (VOP_RECLAIM(vp, td)) 2937 panic("vgone: cannot reclaim"); 2938 if (mp != NULL) 2939 vn_finished_secondary_write(mp); 2940 VNASSERT(vp->v_object == NULL, vp, 2941 ("vop_reclaim left v_object vp=%p, tag=%s", vp, vp->v_tag)); 2942 /* 2943 * Clear the advisory locks and wake up waiting threads. 2944 */ 2945 (void)VOP_ADVLOCKPURGE(vp); 2946 /* 2947 * Delete from old mount point vnode list. 2948 */ 2949 delmntque(vp); 2950 cache_purge(vp); 2951 /* 2952 * Done with purge, reset to the standard lock and invalidate 2953 * the vnode. 2954 */ 2955 VI_LOCK(vp); 2956 vp->v_vnlock = &vp->v_lock; 2957 vp->v_op = &dead_vnodeops; 2958 vp->v_tag = "none"; 2959 vp->v_type = VBAD; 2960 } 2961 2962 /* 2963 * Calculate the total number of references to a special device. 2964 */ 2965 int 2966 vcount(struct vnode *vp) 2967 { 2968 int count; 2969 2970 dev_lock(); 2971 count = vp->v_rdev->si_usecount; 2972 dev_unlock(); 2973 return (count); 2974 } 2975 2976 /* 2977 * Same as above, but using the struct cdev *as argument 2978 */ 2979 int 2980 count_dev(struct cdev *dev) 2981 { 2982 int count; 2983 2984 dev_lock(); 2985 count = dev->si_usecount; 2986 dev_unlock(); 2987 return(count); 2988 } 2989 2990 /* 2991 * Print out a description of a vnode. 2992 */ 2993 static char *typename[] = 2994 {"VNON", "VREG", "VDIR", "VBLK", "VCHR", "VLNK", "VSOCK", "VFIFO", "VBAD", 2995 "VMARKER"}; 2996 2997 void 2998 vn_printf(struct vnode *vp, const char *fmt, ...) 2999 { 3000 va_list ap; 3001 char buf[256], buf2[16]; 3002 u_long flags; 3003 3004 va_start(ap, fmt); 3005 vprintf(fmt, ap); 3006 va_end(ap); 3007 printf("%p: ", (void *)vp); 3008 printf("tag %s, type %s\n", vp->v_tag, typename[vp->v_type]); 3009 printf(" usecount %d, writecount %d, refcount %d mountedhere %p\n", 3010 vp->v_usecount, vp->v_writecount, vp->v_holdcnt, vp->v_mountedhere); 3011 buf[0] = '\0'; 3012 buf[1] = '\0'; 3013 if (vp->v_vflag & VV_ROOT) 3014 strlcat(buf, "|VV_ROOT", sizeof(buf)); 3015 if (vp->v_vflag & VV_ISTTY) 3016 strlcat(buf, "|VV_ISTTY", sizeof(buf)); 3017 if (vp->v_vflag & VV_NOSYNC) 3018 strlcat(buf, "|VV_NOSYNC", sizeof(buf)); 3019 if (vp->v_vflag & VV_ETERNALDEV) 3020 strlcat(buf, "|VV_ETERNALDEV", sizeof(buf)); 3021 if (vp->v_vflag & VV_CACHEDLABEL) 3022 strlcat(buf, "|VV_CACHEDLABEL", sizeof(buf)); 3023 if (vp->v_vflag & VV_TEXT) 3024 strlcat(buf, "|VV_TEXT", sizeof(buf)); 3025 if (vp->v_vflag & VV_COPYONWRITE) 3026 strlcat(buf, "|VV_COPYONWRITE", sizeof(buf)); 3027 if (vp->v_vflag & VV_SYSTEM) 3028 strlcat(buf, "|VV_SYSTEM", sizeof(buf)); 3029 if (vp->v_vflag & VV_PROCDEP) 3030 strlcat(buf, "|VV_PROCDEP", sizeof(buf)); 3031 if (vp->v_vflag & VV_NOKNOTE) 3032 strlcat(buf, "|VV_NOKNOTE", sizeof(buf)); 3033 if (vp->v_vflag & VV_DELETED) 3034 strlcat(buf, "|VV_DELETED", sizeof(buf)); 3035 if (vp->v_vflag & VV_MD) 3036 strlcat(buf, "|VV_MD", sizeof(buf)); 3037 if (vp->v_vflag & VV_FORCEINSMQ) 3038 strlcat(buf, "|VV_FORCEINSMQ", sizeof(buf)); 3039 flags = vp->v_vflag & ~(VV_ROOT | VV_ISTTY | VV_NOSYNC | VV_ETERNALDEV | 3040 VV_CACHEDLABEL | VV_TEXT | VV_COPYONWRITE | VV_SYSTEM | VV_PROCDEP | 3041 VV_NOKNOTE | VV_DELETED | VV_MD | VV_FORCEINSMQ); 3042 if (flags != 0) { 3043 snprintf(buf2, sizeof(buf2), "|VV(0x%lx)", flags); 3044 strlcat(buf, buf2, sizeof(buf)); 3045 } 3046 if (vp->v_iflag & VI_MOUNT) 3047 strlcat(buf, "|VI_MOUNT", sizeof(buf)); 3048 if (vp->v_iflag & VI_AGE) 3049 strlcat(buf, "|VI_AGE", sizeof(buf)); 3050 if (vp->v_iflag & VI_DOOMED) 3051 strlcat(buf, "|VI_DOOMED", sizeof(buf)); 3052 if (vp->v_iflag & VI_FREE) 3053 strlcat(buf, "|VI_FREE", sizeof(buf)); 3054 if (vp->v_iflag & VI_ACTIVE) 3055 strlcat(buf, "|VI_ACTIVE", sizeof(buf)); 3056 if (vp->v_iflag & VI_DOINGINACT) 3057 strlcat(buf, "|VI_DOINGINACT", sizeof(buf)); 3058 if (vp->v_iflag & VI_OWEINACT) 3059 strlcat(buf, "|VI_OWEINACT", sizeof(buf)); 3060 flags = vp->v_iflag & ~(VI_MOUNT | VI_AGE | VI_DOOMED | VI_FREE | 3061 VI_ACTIVE | VI_DOINGINACT | VI_OWEINACT); 3062 if (flags != 0) { 3063 snprintf(buf2, sizeof(buf2), "|VI(0x%lx)", flags); 3064 strlcat(buf, buf2, sizeof(buf)); 3065 } 3066 printf(" flags (%s)\n", buf + 1); 3067 if (mtx_owned(VI_MTX(vp))) 3068 printf(" VI_LOCKed"); 3069 if (vp->v_object != NULL) 3070 printf(" v_object %p ref %d pages %d " 3071 "cleanbuf %d dirtybuf %d\n", 3072 vp->v_object, vp->v_object->ref_count, 3073 vp->v_object->resident_page_count, 3074 vp->v_bufobj.bo_dirty.bv_cnt, 3075 vp->v_bufobj.bo_clean.bv_cnt); 3076 printf(" "); 3077 lockmgr_printinfo(vp->v_vnlock); 3078 if (vp->v_data != NULL) 3079 VOP_PRINT(vp); 3080 } 3081 3082 #ifdef DDB 3083 /* 3084 * List all of the locked vnodes in the system. 3085 * Called when debugging the kernel. 3086 */ 3087 DB_SHOW_COMMAND(lockedvnods, lockedvnodes) 3088 { 3089 struct mount *mp; 3090 struct vnode *vp; 3091 3092 /* 3093 * Note: because this is DDB, we can't obey the locking semantics 3094 * for these structures, which means we could catch an inconsistent 3095 * state and dereference a nasty pointer. Not much to be done 3096 * about that. 3097 */ 3098 db_printf("Locked vnodes\n"); 3099 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 3100 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) { 3101 if (vp->v_type != VMARKER && VOP_ISLOCKED(vp)) 3102 vprint("", vp); 3103 } 3104 } 3105 } 3106 3107 /* 3108 * Show details about the given vnode. 3109 */ 3110 DB_SHOW_COMMAND(vnode, db_show_vnode) 3111 { 3112 struct vnode *vp; 3113 3114 if (!have_addr) 3115 return; 3116 vp = (struct vnode *)addr; 3117 vn_printf(vp, "vnode "); 3118 } 3119 3120 /* 3121 * Show details about the given mount point. 3122 */ 3123 DB_SHOW_COMMAND(mount, db_show_mount) 3124 { 3125 struct mount *mp; 3126 struct vfsopt *opt; 3127 struct statfs *sp; 3128 struct vnode *vp; 3129 char buf[512]; 3130 uint64_t mflags; 3131 u_int flags; 3132 3133 if (!have_addr) { 3134 /* No address given, print short info about all mount points. */ 3135 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 3136 db_printf("%p %s on %s (%s)\n", mp, 3137 mp->mnt_stat.f_mntfromname, 3138 mp->mnt_stat.f_mntonname, 3139 mp->mnt_stat.f_fstypename); 3140 if (db_pager_quit) 3141 break; 3142 } 3143 db_printf("\nMore info: show mount <addr>\n"); 3144 return; 3145 } 3146 3147 mp = (struct mount *)addr; 3148 db_printf("%p %s on %s (%s)\n", mp, mp->mnt_stat.f_mntfromname, 3149 mp->mnt_stat.f_mntonname, mp->mnt_stat.f_fstypename); 3150 3151 buf[0] = '\0'; 3152 mflags = mp->mnt_flag; 3153 #define MNT_FLAG(flag) do { \ 3154 if (mflags & (flag)) { \ 3155 if (buf[0] != '\0') \ 3156 strlcat(buf, ", ", sizeof(buf)); \ 3157 strlcat(buf, (#flag) + 4, sizeof(buf)); \ 3158 mflags &= ~(flag); \ 3159 } \ 3160 } while (0) 3161 MNT_FLAG(MNT_RDONLY); 3162 MNT_FLAG(MNT_SYNCHRONOUS); 3163 MNT_FLAG(MNT_NOEXEC); 3164 MNT_FLAG(MNT_NOSUID); 3165 MNT_FLAG(MNT_NFS4ACLS); 3166 MNT_FLAG(MNT_UNION); 3167 MNT_FLAG(MNT_ASYNC); 3168 MNT_FLAG(MNT_SUIDDIR); 3169 MNT_FLAG(MNT_SOFTDEP); 3170 MNT_FLAG(MNT_NOSYMFOLLOW); 3171 MNT_FLAG(MNT_GJOURNAL); 3172 MNT_FLAG(MNT_MULTILABEL); 3173 MNT_FLAG(MNT_ACLS); 3174 MNT_FLAG(MNT_NOATIME); 3175 MNT_FLAG(MNT_NOCLUSTERR); 3176 MNT_FLAG(MNT_NOCLUSTERW); 3177 MNT_FLAG(MNT_SUJ); 3178 MNT_FLAG(MNT_EXRDONLY); 3179 MNT_FLAG(MNT_EXPORTED); 3180 MNT_FLAG(MNT_DEFEXPORTED); 3181 MNT_FLAG(MNT_EXPORTANON); 3182 MNT_FLAG(MNT_EXKERB); 3183 MNT_FLAG(MNT_EXPUBLIC); 3184 MNT_FLAG(MNT_LOCAL); 3185 MNT_FLAG(MNT_QUOTA); 3186 MNT_FLAG(MNT_ROOTFS); 3187 MNT_FLAG(MNT_USER); 3188 MNT_FLAG(MNT_IGNORE); 3189 MNT_FLAG(MNT_UPDATE); 3190 MNT_FLAG(MNT_DELEXPORT); 3191 MNT_FLAG(MNT_RELOAD); 3192 MNT_FLAG(MNT_FORCE); 3193 MNT_FLAG(MNT_SNAPSHOT); 3194 MNT_FLAG(MNT_BYFSID); 3195 #undef MNT_FLAG 3196 if (mflags != 0) { 3197 if (buf[0] != '\0') 3198 strlcat(buf, ", ", sizeof(buf)); 3199 snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf), 3200 "0x%016jx", mflags); 3201 } 3202 db_printf(" mnt_flag = %s\n", buf); 3203 3204 buf[0] = '\0'; 3205 flags = mp->mnt_kern_flag; 3206 #define MNT_KERN_FLAG(flag) do { \ 3207 if (flags & (flag)) { \ 3208 if (buf[0] != '\0') \ 3209 strlcat(buf, ", ", sizeof(buf)); \ 3210 strlcat(buf, (#flag) + 5, sizeof(buf)); \ 3211 flags &= ~(flag); \ 3212 } \ 3213 } while (0) 3214 MNT_KERN_FLAG(MNTK_UNMOUNTF); 3215 MNT_KERN_FLAG(MNTK_ASYNC); 3216 MNT_KERN_FLAG(MNTK_SOFTDEP); 3217 MNT_KERN_FLAG(MNTK_NOINSMNTQ); 3218 MNT_KERN_FLAG(MNTK_DRAINING); 3219 MNT_KERN_FLAG(MNTK_REFEXPIRE); 3220 MNT_KERN_FLAG(MNTK_EXTENDED_SHARED); 3221 MNT_KERN_FLAG(MNTK_SHARED_WRITES); 3222 MNT_KERN_FLAG(MNTK_NO_IOPF); 3223 MNT_KERN_FLAG(MNTK_VGONE_UPPER); 3224 MNT_KERN_FLAG(MNTK_VGONE_WAITER); 3225 MNT_KERN_FLAG(MNTK_LOOKUP_EXCL_DOTDOT); 3226 MNT_KERN_FLAG(MNTK_MARKER); 3227 MNT_KERN_FLAG(MNTK_USES_BCACHE); 3228 MNT_KERN_FLAG(MNTK_NOASYNC); 3229 MNT_KERN_FLAG(MNTK_UNMOUNT); 3230 MNT_KERN_FLAG(MNTK_MWAIT); 3231 MNT_KERN_FLAG(MNTK_SUSPEND); 3232 MNT_KERN_FLAG(MNTK_SUSPEND2); 3233 MNT_KERN_FLAG(MNTK_SUSPENDED); 3234 MNT_KERN_FLAG(MNTK_LOOKUP_SHARED); 3235 MNT_KERN_FLAG(MNTK_NOKNOTE); 3236 #undef MNT_KERN_FLAG 3237 if (flags != 0) { 3238 if (buf[0] != '\0') 3239 strlcat(buf, ", ", sizeof(buf)); 3240 snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf), 3241 "0x%08x", flags); 3242 } 3243 db_printf(" mnt_kern_flag = %s\n", buf); 3244 3245 db_printf(" mnt_opt = "); 3246 opt = TAILQ_FIRST(mp->mnt_opt); 3247 if (opt != NULL) { 3248 db_printf("%s", opt->name); 3249 opt = TAILQ_NEXT(opt, link); 3250 while (opt != NULL) { 3251 db_printf(", %s", opt->name); 3252 opt = TAILQ_NEXT(opt, link); 3253 } 3254 } 3255 db_printf("\n"); 3256 3257 sp = &mp->mnt_stat; 3258 db_printf(" mnt_stat = { version=%u type=%u flags=0x%016jx " 3259 "bsize=%ju iosize=%ju blocks=%ju bfree=%ju bavail=%jd files=%ju " 3260 "ffree=%jd syncwrites=%ju asyncwrites=%ju syncreads=%ju " 3261 "asyncreads=%ju namemax=%u owner=%u fsid=[%d, %d] }\n", 3262 (u_int)sp->f_version, (u_int)sp->f_type, (uintmax_t)sp->f_flags, 3263 (uintmax_t)sp->f_bsize, (uintmax_t)sp->f_iosize, 3264 (uintmax_t)sp->f_blocks, (uintmax_t)sp->f_bfree, 3265 (intmax_t)sp->f_bavail, (uintmax_t)sp->f_files, 3266 (intmax_t)sp->f_ffree, (uintmax_t)sp->f_syncwrites, 3267 (uintmax_t)sp->f_asyncwrites, (uintmax_t)sp->f_syncreads, 3268 (uintmax_t)sp->f_asyncreads, (u_int)sp->f_namemax, 3269 (u_int)sp->f_owner, (int)sp->f_fsid.val[0], (int)sp->f_fsid.val[1]); 3270 3271 db_printf(" mnt_cred = { uid=%u ruid=%u", 3272 (u_int)mp->mnt_cred->cr_uid, (u_int)mp->mnt_cred->cr_ruid); 3273 if (jailed(mp->mnt_cred)) 3274 db_printf(", jail=%d", mp->mnt_cred->cr_prison->pr_id); 3275 db_printf(" }\n"); 3276 db_printf(" mnt_ref = %d\n", mp->mnt_ref); 3277 db_printf(" mnt_gen = %d\n", mp->mnt_gen); 3278 db_printf(" mnt_nvnodelistsize = %d\n", mp->mnt_nvnodelistsize); 3279 db_printf(" mnt_activevnodelistsize = %d\n", 3280 mp->mnt_activevnodelistsize); 3281 db_printf(" mnt_writeopcount = %d\n", mp->mnt_writeopcount); 3282 db_printf(" mnt_maxsymlinklen = %d\n", mp->mnt_maxsymlinklen); 3283 db_printf(" mnt_iosize_max = %d\n", mp->mnt_iosize_max); 3284 db_printf(" mnt_hashseed = %u\n", mp->mnt_hashseed); 3285 db_printf(" mnt_lockref = %d\n", mp->mnt_lockref); 3286 db_printf(" mnt_secondary_writes = %d\n", mp->mnt_secondary_writes); 3287 db_printf(" mnt_secondary_accwrites = %d\n", 3288 mp->mnt_secondary_accwrites); 3289 db_printf(" mnt_gjprovider = %s\n", 3290 mp->mnt_gjprovider != NULL ? mp->mnt_gjprovider : "NULL"); 3291 3292 db_printf("\n\nList of active vnodes\n"); 3293 TAILQ_FOREACH(vp, &mp->mnt_activevnodelist, v_actfreelist) { 3294 if (vp->v_type != VMARKER) { 3295 vn_printf(vp, "vnode "); 3296 if (db_pager_quit) 3297 break; 3298 } 3299 } 3300 db_printf("\n\nList of inactive vnodes\n"); 3301 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) { 3302 if (vp->v_type != VMARKER && (vp->v_iflag & VI_ACTIVE) == 0) { 3303 vn_printf(vp, "vnode "); 3304 if (db_pager_quit) 3305 break; 3306 } 3307 } 3308 } 3309 #endif /* DDB */ 3310 3311 /* 3312 * Fill in a struct xvfsconf based on a struct vfsconf. 3313 */ 3314 static int 3315 vfsconf2x(struct sysctl_req *req, struct vfsconf *vfsp) 3316 { 3317 struct xvfsconf xvfsp; 3318 3319 bzero(&xvfsp, sizeof(xvfsp)); 3320 strcpy(xvfsp.vfc_name, vfsp->vfc_name); 3321 xvfsp.vfc_typenum = vfsp->vfc_typenum; 3322 xvfsp.vfc_refcount = vfsp->vfc_refcount; 3323 xvfsp.vfc_flags = vfsp->vfc_flags; 3324 /* 3325 * These are unused in userland, we keep them 3326 * to not break binary compatibility. 3327 */ 3328 xvfsp.vfc_vfsops = NULL; 3329 xvfsp.vfc_next = NULL; 3330 return (SYSCTL_OUT(req, &xvfsp, sizeof(xvfsp))); 3331 } 3332 3333 #ifdef COMPAT_FREEBSD32 3334 struct xvfsconf32 { 3335 uint32_t vfc_vfsops; 3336 char vfc_name[MFSNAMELEN]; 3337 int32_t vfc_typenum; 3338 int32_t vfc_refcount; 3339 int32_t vfc_flags; 3340 uint32_t vfc_next; 3341 }; 3342 3343 static int 3344 vfsconf2x32(struct sysctl_req *req, struct vfsconf *vfsp) 3345 { 3346 struct xvfsconf32 xvfsp; 3347 3348 strcpy(xvfsp.vfc_name, vfsp->vfc_name); 3349 xvfsp.vfc_typenum = vfsp->vfc_typenum; 3350 xvfsp.vfc_refcount = vfsp->vfc_refcount; 3351 xvfsp.vfc_flags = vfsp->vfc_flags; 3352 xvfsp.vfc_vfsops = 0; 3353 xvfsp.vfc_next = 0; 3354 return (SYSCTL_OUT(req, &xvfsp, sizeof(xvfsp))); 3355 } 3356 #endif 3357 3358 /* 3359 * Top level filesystem related information gathering. 3360 */ 3361 static int 3362 sysctl_vfs_conflist(SYSCTL_HANDLER_ARGS) 3363 { 3364 struct vfsconf *vfsp; 3365 int error; 3366 3367 error = 0; 3368 vfsconf_slock(); 3369 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) { 3370 #ifdef COMPAT_FREEBSD32 3371 if (req->flags & SCTL_MASK32) 3372 error = vfsconf2x32(req, vfsp); 3373 else 3374 #endif 3375 error = vfsconf2x(req, vfsp); 3376 if (error) 3377 break; 3378 } 3379 vfsconf_sunlock(); 3380 return (error); 3381 } 3382 3383 SYSCTL_PROC(_vfs, OID_AUTO, conflist, CTLTYPE_OPAQUE | CTLFLAG_RD | 3384 CTLFLAG_MPSAFE, NULL, 0, sysctl_vfs_conflist, 3385 "S,xvfsconf", "List of all configured filesystems"); 3386 3387 #ifndef BURN_BRIDGES 3388 static int sysctl_ovfs_conf(SYSCTL_HANDLER_ARGS); 3389 3390 static int 3391 vfs_sysctl(SYSCTL_HANDLER_ARGS) 3392 { 3393 int *name = (int *)arg1 - 1; /* XXX */ 3394 u_int namelen = arg2 + 1; /* XXX */ 3395 struct vfsconf *vfsp; 3396 3397 log(LOG_WARNING, "userland calling deprecated sysctl, " 3398 "please rebuild world\n"); 3399 3400 #if 1 || defined(COMPAT_PRELITE2) 3401 /* Resolve ambiguity between VFS_VFSCONF and VFS_GENERIC. */ 3402 if (namelen == 1) 3403 return (sysctl_ovfs_conf(oidp, arg1, arg2, req)); 3404 #endif 3405 3406 switch (name[1]) { 3407 case VFS_MAXTYPENUM: 3408 if (namelen != 2) 3409 return (ENOTDIR); 3410 return (SYSCTL_OUT(req, &maxvfsconf, sizeof(int))); 3411 case VFS_CONF: 3412 if (namelen != 3) 3413 return (ENOTDIR); /* overloaded */ 3414 vfsconf_slock(); 3415 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) { 3416 if (vfsp->vfc_typenum == name[2]) 3417 break; 3418 } 3419 vfsconf_sunlock(); 3420 if (vfsp == NULL) 3421 return (EOPNOTSUPP); 3422 #ifdef COMPAT_FREEBSD32 3423 if (req->flags & SCTL_MASK32) 3424 return (vfsconf2x32(req, vfsp)); 3425 else 3426 #endif 3427 return (vfsconf2x(req, vfsp)); 3428 } 3429 return (EOPNOTSUPP); 3430 } 3431 3432 static SYSCTL_NODE(_vfs, VFS_GENERIC, generic, CTLFLAG_RD | CTLFLAG_SKIP | 3433 CTLFLAG_MPSAFE, vfs_sysctl, 3434 "Generic filesystem"); 3435 3436 #if 1 || defined(COMPAT_PRELITE2) 3437 3438 static int 3439 sysctl_ovfs_conf(SYSCTL_HANDLER_ARGS) 3440 { 3441 int error; 3442 struct vfsconf *vfsp; 3443 struct ovfsconf ovfs; 3444 3445 vfsconf_slock(); 3446 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) { 3447 bzero(&ovfs, sizeof(ovfs)); 3448 ovfs.vfc_vfsops = vfsp->vfc_vfsops; /* XXX used as flag */ 3449 strcpy(ovfs.vfc_name, vfsp->vfc_name); 3450 ovfs.vfc_index = vfsp->vfc_typenum; 3451 ovfs.vfc_refcount = vfsp->vfc_refcount; 3452 ovfs.vfc_flags = vfsp->vfc_flags; 3453 error = SYSCTL_OUT(req, &ovfs, sizeof ovfs); 3454 if (error != 0) { 3455 vfsconf_sunlock(); 3456 return (error); 3457 } 3458 } 3459 vfsconf_sunlock(); 3460 return (0); 3461 } 3462 3463 #endif /* 1 || COMPAT_PRELITE2 */ 3464 #endif /* !BURN_BRIDGES */ 3465 3466 #define KINFO_VNODESLOP 10 3467 #ifdef notyet 3468 /* 3469 * Dump vnode list (via sysctl). 3470 */ 3471 /* ARGSUSED */ 3472 static int 3473 sysctl_vnode(SYSCTL_HANDLER_ARGS) 3474 { 3475 struct xvnode *xvn; 3476 struct mount *mp; 3477 struct vnode *vp; 3478 int error, len, n; 3479 3480 /* 3481 * Stale numvnodes access is not fatal here. 3482 */ 3483 req->lock = 0; 3484 len = (numvnodes + KINFO_VNODESLOP) * sizeof *xvn; 3485 if (!req->oldptr) 3486 /* Make an estimate */ 3487 return (SYSCTL_OUT(req, 0, len)); 3488 3489 error = sysctl_wire_old_buffer(req, 0); 3490 if (error != 0) 3491 return (error); 3492 xvn = malloc(len, M_TEMP, M_ZERO | M_WAITOK); 3493 n = 0; 3494 mtx_lock(&mountlist_mtx); 3495 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 3496 if (vfs_busy(mp, MBF_NOWAIT | MBF_MNTLSTLOCK)) 3497 continue; 3498 MNT_ILOCK(mp); 3499 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) { 3500 if (n == len) 3501 break; 3502 vref(vp); 3503 xvn[n].xv_size = sizeof *xvn; 3504 xvn[n].xv_vnode = vp; 3505 xvn[n].xv_id = 0; /* XXX compat */ 3506 #define XV_COPY(field) xvn[n].xv_##field = vp->v_##field 3507 XV_COPY(usecount); 3508 XV_COPY(writecount); 3509 XV_COPY(holdcnt); 3510 XV_COPY(mount); 3511 XV_COPY(numoutput); 3512 XV_COPY(type); 3513 #undef XV_COPY 3514 xvn[n].xv_flag = vp->v_vflag; 3515 3516 switch (vp->v_type) { 3517 case VREG: 3518 case VDIR: 3519 case VLNK: 3520 break; 3521 case VBLK: 3522 case VCHR: 3523 if (vp->v_rdev == NULL) { 3524 vrele(vp); 3525 continue; 3526 } 3527 xvn[n].xv_dev = dev2udev(vp->v_rdev); 3528 break; 3529 case VSOCK: 3530 xvn[n].xv_socket = vp->v_socket; 3531 break; 3532 case VFIFO: 3533 xvn[n].xv_fifo = vp->v_fifoinfo; 3534 break; 3535 case VNON: 3536 case VBAD: 3537 default: 3538 /* shouldn't happen? */ 3539 vrele(vp); 3540 continue; 3541 } 3542 vrele(vp); 3543 ++n; 3544 } 3545 MNT_IUNLOCK(mp); 3546 mtx_lock(&mountlist_mtx); 3547 vfs_unbusy(mp); 3548 if (n == len) 3549 break; 3550 } 3551 mtx_unlock(&mountlist_mtx); 3552 3553 error = SYSCTL_OUT(req, xvn, n * sizeof *xvn); 3554 free(xvn, M_TEMP); 3555 return (error); 3556 } 3557 3558 SYSCTL_PROC(_kern, KERN_VNODE, vnode, CTLTYPE_OPAQUE | CTLFLAG_RD | 3559 CTLFLAG_MPSAFE, 0, 0, sysctl_vnode, "S,xvnode", 3560 ""); 3561 #endif 3562 3563 static void 3564 unmount_or_warn(struct mount *mp) 3565 { 3566 int error; 3567 3568 error = dounmount(mp, MNT_FORCE, curthread); 3569 if (error != 0) { 3570 printf("unmount of %s failed (", mp->mnt_stat.f_mntonname); 3571 if (error == EBUSY) 3572 printf("BUSY)\n"); 3573 else 3574 printf("%d)\n", error); 3575 } 3576 } 3577 3578 /* 3579 * Unmount all filesystems. The list is traversed in reverse order 3580 * of mounting to avoid dependencies. 3581 */ 3582 void 3583 vfs_unmountall(void) 3584 { 3585 struct mount *mp, *tmp; 3586 3587 CTR1(KTR_VFS, "%s: unmounting all filesystems", __func__); 3588 3589 /* 3590 * Since this only runs when rebooting, it is not interlocked. 3591 */ 3592 TAILQ_FOREACH_REVERSE_SAFE(mp, &mountlist, mntlist, mnt_list, tmp) { 3593 vfs_ref(mp); 3594 3595 /* 3596 * Forcibly unmounting "/dev" before "/" would prevent clean 3597 * unmount of the latter. 3598 */ 3599 if (mp == rootdevmp) 3600 continue; 3601 3602 unmount_or_warn(mp); 3603 } 3604 3605 if (rootdevmp != NULL) 3606 unmount_or_warn(rootdevmp); 3607 } 3608 3609 /* 3610 * perform msync on all vnodes under a mount point 3611 * the mount point must be locked. 3612 */ 3613 void 3614 vfs_msync(struct mount *mp, int flags) 3615 { 3616 struct vnode *vp, *mvp; 3617 struct vm_object *obj; 3618 3619 CTR2(KTR_VFS, "%s: mp %p", __func__, mp); 3620 MNT_VNODE_FOREACH_ACTIVE(vp, mp, mvp) { 3621 obj = vp->v_object; 3622 if (obj != NULL && (obj->flags & OBJ_MIGHTBEDIRTY) != 0 && 3623 (flags == MNT_WAIT || VOP_ISLOCKED(vp) == 0)) { 3624 if (!vget(vp, 3625 LK_EXCLUSIVE | LK_RETRY | LK_INTERLOCK, 3626 curthread)) { 3627 if (vp->v_vflag & VV_NOSYNC) { /* unlinked */ 3628 vput(vp); 3629 continue; 3630 } 3631 3632 obj = vp->v_object; 3633 if (obj != NULL) { 3634 VM_OBJECT_WLOCK(obj); 3635 vm_object_page_clean(obj, 0, 0, 3636 flags == MNT_WAIT ? 3637 OBJPC_SYNC : OBJPC_NOSYNC); 3638 VM_OBJECT_WUNLOCK(obj); 3639 } 3640 vput(vp); 3641 } 3642 } else 3643 VI_UNLOCK(vp); 3644 } 3645 } 3646 3647 static void 3648 destroy_vpollinfo_free(struct vpollinfo *vi) 3649 { 3650 3651 knlist_destroy(&vi->vpi_selinfo.si_note); 3652 mtx_destroy(&vi->vpi_lock); 3653 uma_zfree(vnodepoll_zone, vi); 3654 } 3655 3656 static void 3657 destroy_vpollinfo(struct vpollinfo *vi) 3658 { 3659 3660 knlist_clear(&vi->vpi_selinfo.si_note, 1); 3661 seldrain(&vi->vpi_selinfo); 3662 destroy_vpollinfo_free(vi); 3663 } 3664 3665 /* 3666 * Initalize per-vnode helper structure to hold poll-related state. 3667 */ 3668 void 3669 v_addpollinfo(struct vnode *vp) 3670 { 3671 struct vpollinfo *vi; 3672 3673 if (vp->v_pollinfo != NULL) 3674 return; 3675 vi = uma_zalloc(vnodepoll_zone, M_WAITOK | M_ZERO); 3676 mtx_init(&vi->vpi_lock, "vnode pollinfo", NULL, MTX_DEF); 3677 knlist_init(&vi->vpi_selinfo.si_note, vp, vfs_knllock, 3678 vfs_knlunlock, vfs_knl_assert_locked, vfs_knl_assert_unlocked); 3679 VI_LOCK(vp); 3680 if (vp->v_pollinfo != NULL) { 3681 VI_UNLOCK(vp); 3682 destroy_vpollinfo_free(vi); 3683 return; 3684 } 3685 vp->v_pollinfo = vi; 3686 VI_UNLOCK(vp); 3687 } 3688 3689 /* 3690 * Record a process's interest in events which might happen to 3691 * a vnode. Because poll uses the historic select-style interface 3692 * internally, this routine serves as both the ``check for any 3693 * pending events'' and the ``record my interest in future events'' 3694 * functions. (These are done together, while the lock is held, 3695 * to avoid race conditions.) 3696 */ 3697 int 3698 vn_pollrecord(struct vnode *vp, struct thread *td, int events) 3699 { 3700 3701 v_addpollinfo(vp); 3702 mtx_lock(&vp->v_pollinfo->vpi_lock); 3703 if (vp->v_pollinfo->vpi_revents & events) { 3704 /* 3705 * This leaves events we are not interested 3706 * in available for the other process which 3707 * which presumably had requested them 3708 * (otherwise they would never have been 3709 * recorded). 3710 */ 3711 events &= vp->v_pollinfo->vpi_revents; 3712 vp->v_pollinfo->vpi_revents &= ~events; 3713 3714 mtx_unlock(&vp->v_pollinfo->vpi_lock); 3715 return (events); 3716 } 3717 vp->v_pollinfo->vpi_events |= events; 3718 selrecord(td, &vp->v_pollinfo->vpi_selinfo); 3719 mtx_unlock(&vp->v_pollinfo->vpi_lock); 3720 return (0); 3721 } 3722 3723 /* 3724 * Routine to create and manage a filesystem syncer vnode. 3725 */ 3726 #define sync_close ((int (*)(struct vop_close_args *))nullop) 3727 static int sync_fsync(struct vop_fsync_args *); 3728 static int sync_inactive(struct vop_inactive_args *); 3729 static int sync_reclaim(struct vop_reclaim_args *); 3730 3731 static struct vop_vector sync_vnodeops = { 3732 .vop_bypass = VOP_EOPNOTSUPP, 3733 .vop_close = sync_close, /* close */ 3734 .vop_fsync = sync_fsync, /* fsync */ 3735 .vop_inactive = sync_inactive, /* inactive */ 3736 .vop_reclaim = sync_reclaim, /* reclaim */ 3737 .vop_lock1 = vop_stdlock, /* lock */ 3738 .vop_unlock = vop_stdunlock, /* unlock */ 3739 .vop_islocked = vop_stdislocked, /* islocked */ 3740 }; 3741 3742 /* 3743 * Create a new filesystem syncer vnode for the specified mount point. 3744 */ 3745 void 3746 vfs_allocate_syncvnode(struct mount *mp) 3747 { 3748 struct vnode *vp; 3749 struct bufobj *bo; 3750 static long start, incr, next; 3751 int error; 3752 3753 /* Allocate a new vnode */ 3754 error = getnewvnode("syncer", mp, &sync_vnodeops, &vp); 3755 if (error != 0) 3756 panic("vfs_allocate_syncvnode: getnewvnode() failed"); 3757 vp->v_type = VNON; 3758 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 3759 vp->v_vflag |= VV_FORCEINSMQ; 3760 error = insmntque(vp, mp); 3761 if (error != 0) 3762 panic("vfs_allocate_syncvnode: insmntque() failed"); 3763 vp->v_vflag &= ~VV_FORCEINSMQ; 3764 VOP_UNLOCK(vp, 0); 3765 /* 3766 * Place the vnode onto the syncer worklist. We attempt to 3767 * scatter them about on the list so that they will go off 3768 * at evenly distributed times even if all the filesystems 3769 * are mounted at once. 3770 */ 3771 next += incr; 3772 if (next == 0 || next > syncer_maxdelay) { 3773 start /= 2; 3774 incr /= 2; 3775 if (start == 0) { 3776 start = syncer_maxdelay / 2; 3777 incr = syncer_maxdelay; 3778 } 3779 next = start; 3780 } 3781 bo = &vp->v_bufobj; 3782 BO_LOCK(bo); 3783 vn_syncer_add_to_worklist(bo, syncdelay > 0 ? next % syncdelay : 0); 3784 /* XXX - vn_syncer_add_to_worklist() also grabs and drops sync_mtx. */ 3785 mtx_lock(&sync_mtx); 3786 sync_vnode_count++; 3787 if (mp->mnt_syncer == NULL) { 3788 mp->mnt_syncer = vp; 3789 vp = NULL; 3790 } 3791 mtx_unlock(&sync_mtx); 3792 BO_UNLOCK(bo); 3793 if (vp != NULL) { 3794 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 3795 vgone(vp); 3796 vput(vp); 3797 } 3798 } 3799 3800 void 3801 vfs_deallocate_syncvnode(struct mount *mp) 3802 { 3803 struct vnode *vp; 3804 3805 mtx_lock(&sync_mtx); 3806 vp = mp->mnt_syncer; 3807 if (vp != NULL) 3808 mp->mnt_syncer = NULL; 3809 mtx_unlock(&sync_mtx); 3810 if (vp != NULL) 3811 vrele(vp); 3812 } 3813 3814 /* 3815 * Do a lazy sync of the filesystem. 3816 */ 3817 static int 3818 sync_fsync(struct vop_fsync_args *ap) 3819 { 3820 struct vnode *syncvp = ap->a_vp; 3821 struct mount *mp = syncvp->v_mount; 3822 int error, save; 3823 struct bufobj *bo; 3824 3825 /* 3826 * We only need to do something if this is a lazy evaluation. 3827 */ 3828 if (ap->a_waitfor != MNT_LAZY) 3829 return (0); 3830 3831 /* 3832 * Move ourselves to the back of the sync list. 3833 */ 3834 bo = &syncvp->v_bufobj; 3835 BO_LOCK(bo); 3836 vn_syncer_add_to_worklist(bo, syncdelay); 3837 BO_UNLOCK(bo); 3838 3839 /* 3840 * Walk the list of vnodes pushing all that are dirty and 3841 * not already on the sync list. 3842 */ 3843 if (vfs_busy(mp, MBF_NOWAIT) != 0) 3844 return (0); 3845 if (vn_start_write(NULL, &mp, V_NOWAIT) != 0) { 3846 vfs_unbusy(mp); 3847 return (0); 3848 } 3849 save = curthread_pflags_set(TDP_SYNCIO); 3850 vfs_msync(mp, MNT_NOWAIT); 3851 error = VFS_SYNC(mp, MNT_LAZY); 3852 curthread_pflags_restore(save); 3853 vn_finished_write(mp); 3854 vfs_unbusy(mp); 3855 return (error); 3856 } 3857 3858 /* 3859 * The syncer vnode is no referenced. 3860 */ 3861 static int 3862 sync_inactive(struct vop_inactive_args *ap) 3863 { 3864 3865 vgone(ap->a_vp); 3866 return (0); 3867 } 3868 3869 /* 3870 * The syncer vnode is no longer needed and is being decommissioned. 3871 * 3872 * Modifications to the worklist must be protected by sync_mtx. 3873 */ 3874 static int 3875 sync_reclaim(struct vop_reclaim_args *ap) 3876 { 3877 struct vnode *vp = ap->a_vp; 3878 struct bufobj *bo; 3879 3880 bo = &vp->v_bufobj; 3881 BO_LOCK(bo); 3882 mtx_lock(&sync_mtx); 3883 if (vp->v_mount->mnt_syncer == vp) 3884 vp->v_mount->mnt_syncer = NULL; 3885 if (bo->bo_flag & BO_ONWORKLST) { 3886 LIST_REMOVE(bo, bo_synclist); 3887 syncer_worklist_len--; 3888 sync_vnode_count--; 3889 bo->bo_flag &= ~BO_ONWORKLST; 3890 } 3891 mtx_unlock(&sync_mtx); 3892 BO_UNLOCK(bo); 3893 3894 return (0); 3895 } 3896 3897 /* 3898 * Check if vnode represents a disk device 3899 */ 3900 int 3901 vn_isdisk(struct vnode *vp, int *errp) 3902 { 3903 int error; 3904 3905 if (vp->v_type != VCHR) { 3906 error = ENOTBLK; 3907 goto out; 3908 } 3909 error = 0; 3910 dev_lock(); 3911 if (vp->v_rdev == NULL) 3912 error = ENXIO; 3913 else if (vp->v_rdev->si_devsw == NULL) 3914 error = ENXIO; 3915 else if (!(vp->v_rdev->si_devsw->d_flags & D_DISK)) 3916 error = ENOTBLK; 3917 dev_unlock(); 3918 out: 3919 if (errp != NULL) 3920 *errp = error; 3921 return (error == 0); 3922 } 3923 3924 /* 3925 * Common filesystem object access control check routine. Accepts a 3926 * vnode's type, "mode", uid and gid, requested access mode, credentials, 3927 * and optional call-by-reference privused argument allowing vaccess() 3928 * to indicate to the caller whether privilege was used to satisfy the 3929 * request (obsoleted). Returns 0 on success, or an errno on failure. 3930 */ 3931 int 3932 vaccess(enum vtype type, mode_t file_mode, uid_t file_uid, gid_t file_gid, 3933 accmode_t accmode, struct ucred *cred, int *privused) 3934 { 3935 accmode_t dac_granted; 3936 accmode_t priv_granted; 3937 3938 KASSERT((accmode & ~(VEXEC | VWRITE | VREAD | VADMIN | VAPPEND)) == 0, 3939 ("invalid bit in accmode")); 3940 KASSERT((accmode & VAPPEND) == 0 || (accmode & VWRITE), 3941 ("VAPPEND without VWRITE")); 3942 3943 /* 3944 * Look for a normal, non-privileged way to access the file/directory 3945 * as requested. If it exists, go with that. 3946 */ 3947 3948 if (privused != NULL) 3949 *privused = 0; 3950 3951 dac_granted = 0; 3952 3953 /* Check the owner. */ 3954 if (cred->cr_uid == file_uid) { 3955 dac_granted |= VADMIN; 3956 if (file_mode & S_IXUSR) 3957 dac_granted |= VEXEC; 3958 if (file_mode & S_IRUSR) 3959 dac_granted |= VREAD; 3960 if (file_mode & S_IWUSR) 3961 dac_granted |= (VWRITE | VAPPEND); 3962 3963 if ((accmode & dac_granted) == accmode) 3964 return (0); 3965 3966 goto privcheck; 3967 } 3968 3969 /* Otherwise, check the groups (first match) */ 3970 if (groupmember(file_gid, cred)) { 3971 if (file_mode & S_IXGRP) 3972 dac_granted |= VEXEC; 3973 if (file_mode & S_IRGRP) 3974 dac_granted |= VREAD; 3975 if (file_mode & S_IWGRP) 3976 dac_granted |= (VWRITE | VAPPEND); 3977 3978 if ((accmode & dac_granted) == accmode) 3979 return (0); 3980 3981 goto privcheck; 3982 } 3983 3984 /* Otherwise, check everyone else. */ 3985 if (file_mode & S_IXOTH) 3986 dac_granted |= VEXEC; 3987 if (file_mode & S_IROTH) 3988 dac_granted |= VREAD; 3989 if (file_mode & S_IWOTH) 3990 dac_granted |= (VWRITE | VAPPEND); 3991 if ((accmode & dac_granted) == accmode) 3992 return (0); 3993 3994 privcheck: 3995 /* 3996 * Build a privilege mask to determine if the set of privileges 3997 * satisfies the requirements when combined with the granted mask 3998 * from above. For each privilege, if the privilege is required, 3999 * bitwise or the request type onto the priv_granted mask. 4000 */ 4001 priv_granted = 0; 4002 4003 if (type == VDIR) { 4004 /* 4005 * For directories, use PRIV_VFS_LOOKUP to satisfy VEXEC 4006 * requests, instead of PRIV_VFS_EXEC. 4007 */ 4008 if ((accmode & VEXEC) && ((dac_granted & VEXEC) == 0) && 4009 !priv_check_cred(cred, PRIV_VFS_LOOKUP, 0)) 4010 priv_granted |= VEXEC; 4011 } else { 4012 /* 4013 * Ensure that at least one execute bit is on. Otherwise, 4014 * a privileged user will always succeed, and we don't want 4015 * this to happen unless the file really is executable. 4016 */ 4017 if ((accmode & VEXEC) && ((dac_granted & VEXEC) == 0) && 4018 (file_mode & (S_IXUSR | S_IXGRP | S_IXOTH)) != 0 && 4019 !priv_check_cred(cred, PRIV_VFS_EXEC, 0)) 4020 priv_granted |= VEXEC; 4021 } 4022 4023 if ((accmode & VREAD) && ((dac_granted & VREAD) == 0) && 4024 !priv_check_cred(cred, PRIV_VFS_READ, 0)) 4025 priv_granted |= VREAD; 4026 4027 if ((accmode & VWRITE) && ((dac_granted & VWRITE) == 0) && 4028 !priv_check_cred(cred, PRIV_VFS_WRITE, 0)) 4029 priv_granted |= (VWRITE | VAPPEND); 4030 4031 if ((accmode & VADMIN) && ((dac_granted & VADMIN) == 0) && 4032 !priv_check_cred(cred, PRIV_VFS_ADMIN, 0)) 4033 priv_granted |= VADMIN; 4034 4035 if ((accmode & (priv_granted | dac_granted)) == accmode) { 4036 /* XXX audit: privilege used */ 4037 if (privused != NULL) 4038 *privused = 1; 4039 return (0); 4040 } 4041 4042 return ((accmode & VADMIN) ? EPERM : EACCES); 4043 } 4044 4045 /* 4046 * Credential check based on process requesting service, and per-attribute 4047 * permissions. 4048 */ 4049 int 4050 extattr_check_cred(struct vnode *vp, int attrnamespace, struct ucred *cred, 4051 struct thread *td, accmode_t accmode) 4052 { 4053 4054 /* 4055 * Kernel-invoked always succeeds. 4056 */ 4057 if (cred == NOCRED) 4058 return (0); 4059 4060 /* 4061 * Do not allow privileged processes in jail to directly manipulate 4062 * system attributes. 4063 */ 4064 switch (attrnamespace) { 4065 case EXTATTR_NAMESPACE_SYSTEM: 4066 /* Potentially should be: return (EPERM); */ 4067 return (priv_check_cred(cred, PRIV_VFS_EXTATTR_SYSTEM, 0)); 4068 case EXTATTR_NAMESPACE_USER: 4069 return (VOP_ACCESS(vp, accmode, cred, td)); 4070 default: 4071 return (EPERM); 4072 } 4073 } 4074 4075 #ifdef DEBUG_VFS_LOCKS 4076 /* 4077 * This only exists to supress warnings from unlocked specfs accesses. It is 4078 * no longer ok to have an unlocked VFS. 4079 */ 4080 #define IGNORE_LOCK(vp) (panicstr != NULL || (vp) == NULL || \ 4081 (vp)->v_type == VCHR || (vp)->v_type == VBAD) 4082 4083 int vfs_badlock_ddb = 1; /* Drop into debugger on violation. */ 4084 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_ddb, CTLFLAG_RW, &vfs_badlock_ddb, 0, 4085 "Drop into debugger on lock violation"); 4086 4087 int vfs_badlock_mutex = 1; /* Check for interlock across VOPs. */ 4088 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_mutex, CTLFLAG_RW, &vfs_badlock_mutex, 4089 0, "Check for interlock across VOPs"); 4090 4091 int vfs_badlock_print = 1; /* Print lock violations. */ 4092 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_print, CTLFLAG_RW, &vfs_badlock_print, 4093 0, "Print lock violations"); 4094 4095 #ifdef KDB 4096 int vfs_badlock_backtrace = 1; /* Print backtrace at lock violations. */ 4097 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_backtrace, CTLFLAG_RW, 4098 &vfs_badlock_backtrace, 0, "Print backtrace at lock violations"); 4099 #endif 4100 4101 static void 4102 vfs_badlock(const char *msg, const char *str, struct vnode *vp) 4103 { 4104 4105 #ifdef KDB 4106 if (vfs_badlock_backtrace) 4107 kdb_backtrace(); 4108 #endif 4109 if (vfs_badlock_print) 4110 printf("%s: %p %s\n", str, (void *)vp, msg); 4111 if (vfs_badlock_ddb) 4112 kdb_enter(KDB_WHY_VFSLOCK, "lock violation"); 4113 } 4114 4115 void 4116 assert_vi_locked(struct vnode *vp, const char *str) 4117 { 4118 4119 if (vfs_badlock_mutex && !mtx_owned(VI_MTX(vp))) 4120 vfs_badlock("interlock is not locked but should be", str, vp); 4121 } 4122 4123 void 4124 assert_vi_unlocked(struct vnode *vp, const char *str) 4125 { 4126 4127 if (vfs_badlock_mutex && mtx_owned(VI_MTX(vp))) 4128 vfs_badlock("interlock is locked but should not be", str, vp); 4129 } 4130 4131 void 4132 assert_vop_locked(struct vnode *vp, const char *str) 4133 { 4134 int locked; 4135 4136 if (!IGNORE_LOCK(vp)) { 4137 locked = VOP_ISLOCKED(vp); 4138 if (locked == 0 || locked == LK_EXCLOTHER) 4139 vfs_badlock("is not locked but should be", str, vp); 4140 } 4141 } 4142 4143 void 4144 assert_vop_unlocked(struct vnode *vp, const char *str) 4145 { 4146 4147 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) == LK_EXCLUSIVE) 4148 vfs_badlock("is locked but should not be", str, vp); 4149 } 4150 4151 void 4152 assert_vop_elocked(struct vnode *vp, const char *str) 4153 { 4154 4155 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) != LK_EXCLUSIVE) 4156 vfs_badlock("is not exclusive locked but should be", str, vp); 4157 } 4158 4159 #if 0 4160 void 4161 assert_vop_elocked_other(struct vnode *vp, const char *str) 4162 { 4163 4164 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) != LK_EXCLOTHER) 4165 vfs_badlock("is not exclusive locked by another thread", 4166 str, vp); 4167 } 4168 4169 void 4170 assert_vop_slocked(struct vnode *vp, const char *str) 4171 { 4172 4173 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) != LK_SHARED) 4174 vfs_badlock("is not locked shared but should be", str, vp); 4175 } 4176 #endif /* 0 */ 4177 #endif /* DEBUG_VFS_LOCKS */ 4178 4179 void 4180 vop_rename_fail(struct vop_rename_args *ap) 4181 { 4182 4183 if (ap->a_tvp != NULL) 4184 vput(ap->a_tvp); 4185 if (ap->a_tdvp == ap->a_tvp) 4186 vrele(ap->a_tdvp); 4187 else 4188 vput(ap->a_tdvp); 4189 vrele(ap->a_fdvp); 4190 vrele(ap->a_fvp); 4191 } 4192 4193 void 4194 vop_rename_pre(void *ap) 4195 { 4196 struct vop_rename_args *a = ap; 4197 4198 #ifdef DEBUG_VFS_LOCKS 4199 if (a->a_tvp) 4200 ASSERT_VI_UNLOCKED(a->a_tvp, "VOP_RENAME"); 4201 ASSERT_VI_UNLOCKED(a->a_tdvp, "VOP_RENAME"); 4202 ASSERT_VI_UNLOCKED(a->a_fvp, "VOP_RENAME"); 4203 ASSERT_VI_UNLOCKED(a->a_fdvp, "VOP_RENAME"); 4204 4205 /* Check the source (from). */ 4206 if (a->a_tdvp->v_vnlock != a->a_fdvp->v_vnlock && 4207 (a->a_tvp == NULL || a->a_tvp->v_vnlock != a->a_fdvp->v_vnlock)) 4208 ASSERT_VOP_UNLOCKED(a->a_fdvp, "vop_rename: fdvp locked"); 4209 if (a->a_tvp == NULL || a->a_tvp->v_vnlock != a->a_fvp->v_vnlock) 4210 ASSERT_VOP_UNLOCKED(a->a_fvp, "vop_rename: fvp locked"); 4211 4212 /* Check the target. */ 4213 if (a->a_tvp) 4214 ASSERT_VOP_LOCKED(a->a_tvp, "vop_rename: tvp not locked"); 4215 ASSERT_VOP_LOCKED(a->a_tdvp, "vop_rename: tdvp not locked"); 4216 #endif 4217 if (a->a_tdvp != a->a_fdvp) 4218 vhold(a->a_fdvp); 4219 if (a->a_tvp != a->a_fvp) 4220 vhold(a->a_fvp); 4221 vhold(a->a_tdvp); 4222 if (a->a_tvp) 4223 vhold(a->a_tvp); 4224 } 4225 4226 void 4227 vop_strategy_pre(void *ap) 4228 { 4229 #ifdef DEBUG_VFS_LOCKS 4230 struct vop_strategy_args *a; 4231 struct buf *bp; 4232 4233 a = ap; 4234 bp = a->a_bp; 4235 4236 /* 4237 * Cluster ops lock their component buffers but not the IO container. 4238 */ 4239 if ((bp->b_flags & B_CLUSTER) != 0) 4240 return; 4241 4242 if (panicstr == NULL && !BUF_ISLOCKED(bp)) { 4243 if (vfs_badlock_print) 4244 printf( 4245 "VOP_STRATEGY: bp is not locked but should be\n"); 4246 if (vfs_badlock_ddb) 4247 kdb_enter(KDB_WHY_VFSLOCK, "lock violation"); 4248 } 4249 #endif 4250 } 4251 4252 void 4253 vop_lock_pre(void *ap) 4254 { 4255 #ifdef DEBUG_VFS_LOCKS 4256 struct vop_lock1_args *a = ap; 4257 4258 if ((a->a_flags & LK_INTERLOCK) == 0) 4259 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_LOCK"); 4260 else 4261 ASSERT_VI_LOCKED(a->a_vp, "VOP_LOCK"); 4262 #endif 4263 } 4264 4265 void 4266 vop_lock_post(void *ap, int rc) 4267 { 4268 #ifdef DEBUG_VFS_LOCKS 4269 struct vop_lock1_args *a = ap; 4270 4271 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_LOCK"); 4272 if (rc == 0 && (a->a_flags & LK_EXCLOTHER) == 0) 4273 ASSERT_VOP_LOCKED(a->a_vp, "VOP_LOCK"); 4274 #endif 4275 } 4276 4277 void 4278 vop_unlock_pre(void *ap) 4279 { 4280 #ifdef DEBUG_VFS_LOCKS 4281 struct vop_unlock_args *a = ap; 4282 4283 if (a->a_flags & LK_INTERLOCK) 4284 ASSERT_VI_LOCKED(a->a_vp, "VOP_UNLOCK"); 4285 ASSERT_VOP_LOCKED(a->a_vp, "VOP_UNLOCK"); 4286 #endif 4287 } 4288 4289 void 4290 vop_unlock_post(void *ap, int rc) 4291 { 4292 #ifdef DEBUG_VFS_LOCKS 4293 struct vop_unlock_args *a = ap; 4294 4295 if (a->a_flags & LK_INTERLOCK) 4296 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_UNLOCK"); 4297 #endif 4298 } 4299 4300 void 4301 vop_create_post(void *ap, int rc) 4302 { 4303 struct vop_create_args *a = ap; 4304 4305 if (!rc) 4306 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 4307 } 4308 4309 void 4310 vop_deleteextattr_post(void *ap, int rc) 4311 { 4312 struct vop_deleteextattr_args *a = ap; 4313 4314 if (!rc) 4315 VFS_KNOTE_LOCKED(a->a_vp, NOTE_ATTRIB); 4316 } 4317 4318 void 4319 vop_link_post(void *ap, int rc) 4320 { 4321 struct vop_link_args *a = ap; 4322 4323 if (!rc) { 4324 VFS_KNOTE_LOCKED(a->a_vp, NOTE_LINK); 4325 VFS_KNOTE_LOCKED(a->a_tdvp, NOTE_WRITE); 4326 } 4327 } 4328 4329 void 4330 vop_mkdir_post(void *ap, int rc) 4331 { 4332 struct vop_mkdir_args *a = ap; 4333 4334 if (!rc) 4335 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE | NOTE_LINK); 4336 } 4337 4338 void 4339 vop_mknod_post(void *ap, int rc) 4340 { 4341 struct vop_mknod_args *a = ap; 4342 4343 if (!rc) 4344 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 4345 } 4346 4347 void 4348 vop_reclaim_post(void *ap, int rc) 4349 { 4350 struct vop_reclaim_args *a = ap; 4351 4352 if (!rc) 4353 VFS_KNOTE_LOCKED(a->a_vp, NOTE_REVOKE); 4354 } 4355 4356 void 4357 vop_remove_post(void *ap, int rc) 4358 { 4359 struct vop_remove_args *a = ap; 4360 4361 if (!rc) { 4362 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 4363 VFS_KNOTE_LOCKED(a->a_vp, NOTE_DELETE); 4364 } 4365 } 4366 4367 void 4368 vop_rename_post(void *ap, int rc) 4369 { 4370 struct vop_rename_args *a = ap; 4371 4372 if (!rc) { 4373 VFS_KNOTE_UNLOCKED(a->a_fdvp, NOTE_WRITE); 4374 VFS_KNOTE_UNLOCKED(a->a_tdvp, NOTE_WRITE); 4375 VFS_KNOTE_UNLOCKED(a->a_fvp, NOTE_RENAME); 4376 if (a->a_tvp) 4377 VFS_KNOTE_UNLOCKED(a->a_tvp, NOTE_DELETE); 4378 } 4379 if (a->a_tdvp != a->a_fdvp) 4380 vdrop(a->a_fdvp); 4381 if (a->a_tvp != a->a_fvp) 4382 vdrop(a->a_fvp); 4383 vdrop(a->a_tdvp); 4384 if (a->a_tvp) 4385 vdrop(a->a_tvp); 4386 } 4387 4388 void 4389 vop_rmdir_post(void *ap, int rc) 4390 { 4391 struct vop_rmdir_args *a = ap; 4392 4393 if (!rc) { 4394 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE | NOTE_LINK); 4395 VFS_KNOTE_LOCKED(a->a_vp, NOTE_DELETE); 4396 } 4397 } 4398 4399 void 4400 vop_setattr_post(void *ap, int rc) 4401 { 4402 struct vop_setattr_args *a = ap; 4403 4404 if (!rc) 4405 VFS_KNOTE_LOCKED(a->a_vp, NOTE_ATTRIB); 4406 } 4407 4408 void 4409 vop_setextattr_post(void *ap, int rc) 4410 { 4411 struct vop_setextattr_args *a = ap; 4412 4413 if (!rc) 4414 VFS_KNOTE_LOCKED(a->a_vp, NOTE_ATTRIB); 4415 } 4416 4417 void 4418 vop_symlink_post(void *ap, int rc) 4419 { 4420 struct vop_symlink_args *a = ap; 4421 4422 if (!rc) 4423 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 4424 } 4425 4426 static struct knlist fs_knlist; 4427 4428 static void 4429 vfs_event_init(void *arg) 4430 { 4431 knlist_init_mtx(&fs_knlist, NULL); 4432 } 4433 /* XXX - correct order? */ 4434 SYSINIT(vfs_knlist, SI_SUB_VFS, SI_ORDER_ANY, vfs_event_init, NULL); 4435 4436 void 4437 vfs_event_signal(fsid_t *fsid, uint32_t event, intptr_t data __unused) 4438 { 4439 4440 KNOTE_UNLOCKED(&fs_knlist, event); 4441 } 4442 4443 static int filt_fsattach(struct knote *kn); 4444 static void filt_fsdetach(struct knote *kn); 4445 static int filt_fsevent(struct knote *kn, long hint); 4446 4447 struct filterops fs_filtops = { 4448 .f_isfd = 0, 4449 .f_attach = filt_fsattach, 4450 .f_detach = filt_fsdetach, 4451 .f_event = filt_fsevent 4452 }; 4453 4454 static int 4455 filt_fsattach(struct knote *kn) 4456 { 4457 4458 kn->kn_flags |= EV_CLEAR; 4459 knlist_add(&fs_knlist, kn, 0); 4460 return (0); 4461 } 4462 4463 static void 4464 filt_fsdetach(struct knote *kn) 4465 { 4466 4467 knlist_remove(&fs_knlist, kn, 0); 4468 } 4469 4470 static int 4471 filt_fsevent(struct knote *kn, long hint) 4472 { 4473 4474 kn->kn_fflags |= hint; 4475 return (kn->kn_fflags != 0); 4476 } 4477 4478 static int 4479 sysctl_vfs_ctl(SYSCTL_HANDLER_ARGS) 4480 { 4481 struct vfsidctl vc; 4482 int error; 4483 struct mount *mp; 4484 4485 error = SYSCTL_IN(req, &vc, sizeof(vc)); 4486 if (error) 4487 return (error); 4488 if (vc.vc_vers != VFS_CTL_VERS1) 4489 return (EINVAL); 4490 mp = vfs_getvfs(&vc.vc_fsid); 4491 if (mp == NULL) 4492 return (ENOENT); 4493 /* ensure that a specific sysctl goes to the right filesystem. */ 4494 if (strcmp(vc.vc_fstypename, "*") != 0 && 4495 strcmp(vc.vc_fstypename, mp->mnt_vfc->vfc_name) != 0) { 4496 vfs_rel(mp); 4497 return (EINVAL); 4498 } 4499 VCTLTOREQ(&vc, req); 4500 error = VFS_SYSCTL(mp, vc.vc_op, req); 4501 vfs_rel(mp); 4502 return (error); 4503 } 4504 4505 SYSCTL_PROC(_vfs, OID_AUTO, ctl, CTLTYPE_OPAQUE | CTLFLAG_WR, 4506 NULL, 0, sysctl_vfs_ctl, "", 4507 "Sysctl by fsid"); 4508 4509 /* 4510 * Function to initialize a va_filerev field sensibly. 4511 * XXX: Wouldn't a random number make a lot more sense ?? 4512 */ 4513 u_quad_t 4514 init_va_filerev(void) 4515 { 4516 struct bintime bt; 4517 4518 getbinuptime(&bt); 4519 return (((u_quad_t)bt.sec << 32LL) | (bt.frac >> 32LL)); 4520 } 4521 4522 static int filt_vfsread(struct knote *kn, long hint); 4523 static int filt_vfswrite(struct knote *kn, long hint); 4524 static int filt_vfsvnode(struct knote *kn, long hint); 4525 static void filt_vfsdetach(struct knote *kn); 4526 static struct filterops vfsread_filtops = { 4527 .f_isfd = 1, 4528 .f_detach = filt_vfsdetach, 4529 .f_event = filt_vfsread 4530 }; 4531 static struct filterops vfswrite_filtops = { 4532 .f_isfd = 1, 4533 .f_detach = filt_vfsdetach, 4534 .f_event = filt_vfswrite 4535 }; 4536 static struct filterops vfsvnode_filtops = { 4537 .f_isfd = 1, 4538 .f_detach = filt_vfsdetach, 4539 .f_event = filt_vfsvnode 4540 }; 4541 4542 static void 4543 vfs_knllock(void *arg) 4544 { 4545 struct vnode *vp = arg; 4546 4547 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 4548 } 4549 4550 static void 4551 vfs_knlunlock(void *arg) 4552 { 4553 struct vnode *vp = arg; 4554 4555 VOP_UNLOCK(vp, 0); 4556 } 4557 4558 static void 4559 vfs_knl_assert_locked(void *arg) 4560 { 4561 #ifdef DEBUG_VFS_LOCKS 4562 struct vnode *vp = arg; 4563 4564 ASSERT_VOP_LOCKED(vp, "vfs_knl_assert_locked"); 4565 #endif 4566 } 4567 4568 static void 4569 vfs_knl_assert_unlocked(void *arg) 4570 { 4571 #ifdef DEBUG_VFS_LOCKS 4572 struct vnode *vp = arg; 4573 4574 ASSERT_VOP_UNLOCKED(vp, "vfs_knl_assert_unlocked"); 4575 #endif 4576 } 4577 4578 int 4579 vfs_kqfilter(struct vop_kqfilter_args *ap) 4580 { 4581 struct vnode *vp = ap->a_vp; 4582 struct knote *kn = ap->a_kn; 4583 struct knlist *knl; 4584 4585 switch (kn->kn_filter) { 4586 case EVFILT_READ: 4587 kn->kn_fop = &vfsread_filtops; 4588 break; 4589 case EVFILT_WRITE: 4590 kn->kn_fop = &vfswrite_filtops; 4591 break; 4592 case EVFILT_VNODE: 4593 kn->kn_fop = &vfsvnode_filtops; 4594 break; 4595 default: 4596 return (EINVAL); 4597 } 4598 4599 kn->kn_hook = (caddr_t)vp; 4600 4601 v_addpollinfo(vp); 4602 if (vp->v_pollinfo == NULL) 4603 return (ENOMEM); 4604 knl = &vp->v_pollinfo->vpi_selinfo.si_note; 4605 vhold(vp); 4606 knlist_add(knl, kn, 0); 4607 4608 return (0); 4609 } 4610 4611 /* 4612 * Detach knote from vnode 4613 */ 4614 static void 4615 filt_vfsdetach(struct knote *kn) 4616 { 4617 struct vnode *vp = (struct vnode *)kn->kn_hook; 4618 4619 KASSERT(vp->v_pollinfo != NULL, ("Missing v_pollinfo")); 4620 knlist_remove(&vp->v_pollinfo->vpi_selinfo.si_note, kn, 0); 4621 vdrop(vp); 4622 } 4623 4624 /*ARGSUSED*/ 4625 static int 4626 filt_vfsread(struct knote *kn, long hint) 4627 { 4628 struct vnode *vp = (struct vnode *)kn->kn_hook; 4629 struct vattr va; 4630 int res; 4631 4632 /* 4633 * filesystem is gone, so set the EOF flag and schedule 4634 * the knote for deletion. 4635 */ 4636 if (hint == NOTE_REVOKE || (hint == 0 && vp->v_type == VBAD)) { 4637 VI_LOCK(vp); 4638 kn->kn_flags |= (EV_EOF | EV_ONESHOT); 4639 VI_UNLOCK(vp); 4640 return (1); 4641 } 4642 4643 if (VOP_GETATTR(vp, &va, curthread->td_ucred)) 4644 return (0); 4645 4646 VI_LOCK(vp); 4647 kn->kn_data = va.va_size - kn->kn_fp->f_offset; 4648 res = (kn->kn_sfflags & NOTE_FILE_POLL) != 0 || kn->kn_data != 0; 4649 VI_UNLOCK(vp); 4650 return (res); 4651 } 4652 4653 /*ARGSUSED*/ 4654 static int 4655 filt_vfswrite(struct knote *kn, long hint) 4656 { 4657 struct vnode *vp = (struct vnode *)kn->kn_hook; 4658 4659 VI_LOCK(vp); 4660 4661 /* 4662 * filesystem is gone, so set the EOF flag and schedule 4663 * the knote for deletion. 4664 */ 4665 if (hint == NOTE_REVOKE || (hint == 0 && vp->v_type == VBAD)) 4666 kn->kn_flags |= (EV_EOF | EV_ONESHOT); 4667 4668 kn->kn_data = 0; 4669 VI_UNLOCK(vp); 4670 return (1); 4671 } 4672 4673 static int 4674 filt_vfsvnode(struct knote *kn, long hint) 4675 { 4676 struct vnode *vp = (struct vnode *)kn->kn_hook; 4677 int res; 4678 4679 VI_LOCK(vp); 4680 if (kn->kn_sfflags & hint) 4681 kn->kn_fflags |= hint; 4682 if (hint == NOTE_REVOKE || (hint == 0 && vp->v_type == VBAD)) { 4683 kn->kn_flags |= EV_EOF; 4684 VI_UNLOCK(vp); 4685 return (1); 4686 } 4687 res = (kn->kn_fflags != 0); 4688 VI_UNLOCK(vp); 4689 return (res); 4690 } 4691 4692 int 4693 vfs_read_dirent(struct vop_readdir_args *ap, struct dirent *dp, off_t off) 4694 { 4695 int error; 4696 4697 if (dp->d_reclen > ap->a_uio->uio_resid) 4698 return (ENAMETOOLONG); 4699 error = uiomove(dp, dp->d_reclen, ap->a_uio); 4700 if (error) { 4701 if (ap->a_ncookies != NULL) { 4702 if (ap->a_cookies != NULL) 4703 free(ap->a_cookies, M_TEMP); 4704 ap->a_cookies = NULL; 4705 *ap->a_ncookies = 0; 4706 } 4707 return (error); 4708 } 4709 if (ap->a_ncookies == NULL) 4710 return (0); 4711 4712 KASSERT(ap->a_cookies, 4713 ("NULL ap->a_cookies value with non-NULL ap->a_ncookies!")); 4714 4715 *ap->a_cookies = realloc(*ap->a_cookies, 4716 (*ap->a_ncookies + 1) * sizeof(u_long), M_TEMP, M_WAITOK | M_ZERO); 4717 (*ap->a_cookies)[*ap->a_ncookies] = off; 4718 return (0); 4719 } 4720 4721 /* 4722 * Mark for update the access time of the file if the filesystem 4723 * supports VOP_MARKATIME. This functionality is used by execve and 4724 * mmap, so we want to avoid the I/O implied by directly setting 4725 * va_atime for the sake of efficiency. 4726 */ 4727 void 4728 vfs_mark_atime(struct vnode *vp, struct ucred *cred) 4729 { 4730 struct mount *mp; 4731 4732 mp = vp->v_mount; 4733 ASSERT_VOP_LOCKED(vp, "vfs_mark_atime"); 4734 if (mp != NULL && (mp->mnt_flag & (MNT_NOATIME | MNT_RDONLY)) == 0) 4735 (void)VOP_MARKATIME(vp); 4736 } 4737 4738 /* 4739 * The purpose of this routine is to remove granularity from accmode_t, 4740 * reducing it into standard unix access bits - VEXEC, VREAD, VWRITE, 4741 * VADMIN and VAPPEND. 4742 * 4743 * If it returns 0, the caller is supposed to continue with the usual 4744 * access checks using 'accmode' as modified by this routine. If it 4745 * returns nonzero value, the caller is supposed to return that value 4746 * as errno. 4747 * 4748 * Note that after this routine runs, accmode may be zero. 4749 */ 4750 int 4751 vfs_unixify_accmode(accmode_t *accmode) 4752 { 4753 /* 4754 * There is no way to specify explicit "deny" rule using 4755 * file mode or POSIX.1e ACLs. 4756 */ 4757 if (*accmode & VEXPLICIT_DENY) { 4758 *accmode = 0; 4759 return (0); 4760 } 4761 4762 /* 4763 * None of these can be translated into usual access bits. 4764 * Also, the common case for NFSv4 ACLs is to not contain 4765 * either of these bits. Caller should check for VWRITE 4766 * on the containing directory instead. 4767 */ 4768 if (*accmode & (VDELETE_CHILD | VDELETE)) 4769 return (EPERM); 4770 4771 if (*accmode & VADMIN_PERMS) { 4772 *accmode &= ~VADMIN_PERMS; 4773 *accmode |= VADMIN; 4774 } 4775 4776 /* 4777 * There is no way to deny VREAD_ATTRIBUTES, VREAD_ACL 4778 * or VSYNCHRONIZE using file mode or POSIX.1e ACL. 4779 */ 4780 *accmode &= ~(VSTAT_PERMS | VSYNCHRONIZE); 4781 4782 return (0); 4783 } 4784 4785 /* 4786 * These are helper functions for filesystems to traverse all 4787 * their vnodes. See MNT_VNODE_FOREACH_ALL() in sys/mount.h. 4788 * 4789 * This interface replaces MNT_VNODE_FOREACH. 4790 */ 4791 4792 MALLOC_DEFINE(M_VNODE_MARKER, "vnodemarker", "vnode marker"); 4793 4794 struct vnode * 4795 __mnt_vnode_next_all(struct vnode **mvp, struct mount *mp) 4796 { 4797 struct vnode *vp; 4798 4799 if (should_yield()) 4800 kern_yield(PRI_USER); 4801 MNT_ILOCK(mp); 4802 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch")); 4803 vp = TAILQ_NEXT(*mvp, v_nmntvnodes); 4804 while (vp != NULL && (vp->v_type == VMARKER || 4805 (vp->v_iflag & VI_DOOMED) != 0)) 4806 vp = TAILQ_NEXT(vp, v_nmntvnodes); 4807 4808 /* Check if we are done */ 4809 if (vp == NULL) { 4810 __mnt_vnode_markerfree_all(mvp, mp); 4811 /* MNT_IUNLOCK(mp); -- done in above function */ 4812 mtx_assert(MNT_MTX(mp), MA_NOTOWNED); 4813 return (NULL); 4814 } 4815 TAILQ_REMOVE(&mp->mnt_nvnodelist, *mvp, v_nmntvnodes); 4816 TAILQ_INSERT_AFTER(&mp->mnt_nvnodelist, vp, *mvp, v_nmntvnodes); 4817 VI_LOCK(vp); 4818 MNT_IUNLOCK(mp); 4819 return (vp); 4820 } 4821 4822 struct vnode * 4823 __mnt_vnode_first_all(struct vnode **mvp, struct mount *mp) 4824 { 4825 struct vnode *vp; 4826 4827 *mvp = malloc(sizeof(struct vnode), M_VNODE_MARKER, M_WAITOK | M_ZERO); 4828 MNT_ILOCK(mp); 4829 MNT_REF(mp); 4830 (*mvp)->v_type = VMARKER; 4831 4832 vp = TAILQ_FIRST(&mp->mnt_nvnodelist); 4833 while (vp != NULL && (vp->v_type == VMARKER || 4834 (vp->v_iflag & VI_DOOMED) != 0)) 4835 vp = TAILQ_NEXT(vp, v_nmntvnodes); 4836 4837 /* Check if we are done */ 4838 if (vp == NULL) { 4839 MNT_REL(mp); 4840 MNT_IUNLOCK(mp); 4841 free(*mvp, M_VNODE_MARKER); 4842 *mvp = NULL; 4843 return (NULL); 4844 } 4845 (*mvp)->v_mount = mp; 4846 TAILQ_INSERT_AFTER(&mp->mnt_nvnodelist, vp, *mvp, v_nmntvnodes); 4847 VI_LOCK(vp); 4848 MNT_IUNLOCK(mp); 4849 return (vp); 4850 } 4851 4852 4853 void 4854 __mnt_vnode_markerfree_all(struct vnode **mvp, struct mount *mp) 4855 { 4856 4857 if (*mvp == NULL) { 4858 MNT_IUNLOCK(mp); 4859 return; 4860 } 4861 4862 mtx_assert(MNT_MTX(mp), MA_OWNED); 4863 4864 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch")); 4865 TAILQ_REMOVE(&mp->mnt_nvnodelist, *mvp, v_nmntvnodes); 4866 MNT_REL(mp); 4867 MNT_IUNLOCK(mp); 4868 free(*mvp, M_VNODE_MARKER); 4869 *mvp = NULL; 4870 } 4871 4872 /* 4873 * These are helper functions for filesystems to traverse their 4874 * active vnodes. See MNT_VNODE_FOREACH_ACTIVE() in sys/mount.h 4875 */ 4876 static void 4877 mnt_vnode_markerfree_active(struct vnode **mvp, struct mount *mp) 4878 { 4879 4880 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch")); 4881 4882 MNT_ILOCK(mp); 4883 MNT_REL(mp); 4884 MNT_IUNLOCK(mp); 4885 free(*mvp, M_VNODE_MARKER); 4886 *mvp = NULL; 4887 } 4888 4889 static struct vnode * 4890 mnt_vnode_next_active(struct vnode **mvp, struct mount *mp) 4891 { 4892 struct vnode *vp, *nvp; 4893 4894 mtx_assert(&vnode_free_list_mtx, MA_OWNED); 4895 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch")); 4896 restart: 4897 vp = TAILQ_NEXT(*mvp, v_actfreelist); 4898 TAILQ_REMOVE(&mp->mnt_activevnodelist, *mvp, v_actfreelist); 4899 while (vp != NULL) { 4900 if (vp->v_type == VMARKER) { 4901 vp = TAILQ_NEXT(vp, v_actfreelist); 4902 continue; 4903 } 4904 if (!VI_TRYLOCK(vp)) { 4905 if (mp_ncpus == 1 || should_yield()) { 4906 TAILQ_INSERT_BEFORE(vp, *mvp, v_actfreelist); 4907 mtx_unlock(&vnode_free_list_mtx); 4908 pause("vnacti", 1); 4909 mtx_lock(&vnode_free_list_mtx); 4910 goto restart; 4911 } 4912 continue; 4913 } 4914 KASSERT(vp->v_type != VMARKER, ("locked marker %p", vp)); 4915 KASSERT(vp->v_mount == mp || vp->v_mount == NULL, 4916 ("alien vnode on the active list %p %p", vp, mp)); 4917 if (vp->v_mount == mp && (vp->v_iflag & VI_DOOMED) == 0) 4918 break; 4919 nvp = TAILQ_NEXT(vp, v_actfreelist); 4920 VI_UNLOCK(vp); 4921 vp = nvp; 4922 } 4923 4924 /* Check if we are done */ 4925 if (vp == NULL) { 4926 mtx_unlock(&vnode_free_list_mtx); 4927 mnt_vnode_markerfree_active(mvp, mp); 4928 return (NULL); 4929 } 4930 TAILQ_INSERT_AFTER(&mp->mnt_activevnodelist, vp, *mvp, v_actfreelist); 4931 mtx_unlock(&vnode_free_list_mtx); 4932 ASSERT_VI_LOCKED(vp, "active iter"); 4933 KASSERT((vp->v_iflag & VI_ACTIVE) != 0, ("Non-active vp %p", vp)); 4934 return (vp); 4935 } 4936 4937 struct vnode * 4938 __mnt_vnode_next_active(struct vnode **mvp, struct mount *mp) 4939 { 4940 4941 if (should_yield()) 4942 kern_yield(PRI_USER); 4943 mtx_lock(&vnode_free_list_mtx); 4944 return (mnt_vnode_next_active(mvp, mp)); 4945 } 4946 4947 struct vnode * 4948 __mnt_vnode_first_active(struct vnode **mvp, struct mount *mp) 4949 { 4950 struct vnode *vp; 4951 4952 *mvp = malloc(sizeof(struct vnode), M_VNODE_MARKER, M_WAITOK | M_ZERO); 4953 MNT_ILOCK(mp); 4954 MNT_REF(mp); 4955 MNT_IUNLOCK(mp); 4956 (*mvp)->v_type = VMARKER; 4957 (*mvp)->v_mount = mp; 4958 4959 mtx_lock(&vnode_free_list_mtx); 4960 vp = TAILQ_FIRST(&mp->mnt_activevnodelist); 4961 if (vp == NULL) { 4962 mtx_unlock(&vnode_free_list_mtx); 4963 mnt_vnode_markerfree_active(mvp, mp); 4964 return (NULL); 4965 } 4966 TAILQ_INSERT_BEFORE(vp, *mvp, v_actfreelist); 4967 return (mnt_vnode_next_active(mvp, mp)); 4968 } 4969 4970 void 4971 __mnt_vnode_markerfree_active(struct vnode **mvp, struct mount *mp) 4972 { 4973 4974 if (*mvp == NULL) 4975 return; 4976 4977 mtx_lock(&vnode_free_list_mtx); 4978 TAILQ_REMOVE(&mp->mnt_activevnodelist, *mvp, v_actfreelist); 4979 mtx_unlock(&vnode_free_list_mtx); 4980 mnt_vnode_markerfree_active(mvp, mp); 4981 } 4982