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