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