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