1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1989, 1993 5 * The Regents of the University of California. All rights reserved. 6 * (c) UNIX System Laboratories, Inc. 7 * All or some portions of this file are derived from material licensed 8 * to the University of California by American Telephone and Telegraph 9 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 10 * the permission of UNIX System Laboratories, Inc. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 3. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 * 36 * @(#)vfs_subr.c 8.31 (Berkeley) 5/26/95 37 */ 38 39 /* 40 * External virtual filesystem routines 41 */ 42 43 #include <sys/cdefs.h> 44 __FBSDID("$FreeBSD$"); 45 46 #include "opt_ddb.h" 47 #include "opt_watchdog.h" 48 49 #include <sys/param.h> 50 #include <sys/systm.h> 51 #include <sys/bio.h> 52 #include <sys/buf.h> 53 #include <sys/capsicum.h> 54 #include <sys/condvar.h> 55 #include <sys/conf.h> 56 #include <sys/counter.h> 57 #include <sys/dirent.h> 58 #include <sys/event.h> 59 #include <sys/eventhandler.h> 60 #include <sys/extattr.h> 61 #include <sys/file.h> 62 #include <sys/fcntl.h> 63 #include <sys/jail.h> 64 #include <sys/kdb.h> 65 #include <sys/kernel.h> 66 #include <sys/kthread.h> 67 #include <sys/ktr.h> 68 #include <sys/lockf.h> 69 #include <sys/malloc.h> 70 #include <sys/mount.h> 71 #include <sys/namei.h> 72 #include <sys/pctrie.h> 73 #include <sys/priv.h> 74 #include <sys/reboot.h> 75 #include <sys/refcount.h> 76 #include <sys/rwlock.h> 77 #include <sys/sched.h> 78 #include <sys/sleepqueue.h> 79 #include <sys/smp.h> 80 #include <sys/stat.h> 81 #include <sys/sysctl.h> 82 #include <sys/syslog.h> 83 #include <sys/vmmeter.h> 84 #include <sys/vnode.h> 85 #include <sys/watchdog.h> 86 87 #include <machine/stdarg.h> 88 89 #include <security/mac/mac_framework.h> 90 91 #include <vm/vm.h> 92 #include <vm/vm_object.h> 93 #include <vm/vm_extern.h> 94 #include <vm/pmap.h> 95 #include <vm/vm_map.h> 96 #include <vm/vm_page.h> 97 #include <vm/vm_kern.h> 98 #include <vm/uma.h> 99 100 #ifdef DDB 101 #include <ddb/ddb.h> 102 #endif 103 104 static void delmntque(struct vnode *vp); 105 static int flushbuflist(struct bufv *bufv, int flags, struct bufobj *bo, 106 int slpflag, int slptimeo); 107 static void syncer_shutdown(void *arg, int howto); 108 static int vtryrecycle(struct vnode *vp); 109 static void v_init_counters(struct vnode *); 110 static void v_incr_devcount(struct vnode *); 111 static void v_decr_devcount(struct vnode *); 112 static void vgonel(struct vnode *); 113 static void vfs_knllock(void *arg); 114 static void vfs_knlunlock(void *arg); 115 static void vfs_knl_assert_locked(void *arg); 116 static void vfs_knl_assert_unlocked(void *arg); 117 static void vnlru_return_batches(struct vfsops *mnt_op); 118 static void destroy_vpollinfo(struct vpollinfo *vi); 119 static int v_inval_buf_range_locked(struct vnode *vp, struct bufobj *bo, 120 daddr_t startlbn, daddr_t endlbn); 121 122 /* 123 * These fences are intended for cases where some synchronization is 124 * needed between access of v_iflags and lockless vnode refcount (v_holdcnt 125 * and v_usecount) updates. Access to v_iflags is generally synchronized 126 * by the interlock, but we have some internal assertions that check vnode 127 * flags without acquiring the lock. Thus, these fences are INVARIANTS-only 128 * for now. 129 */ 130 #ifdef INVARIANTS 131 #define VNODE_REFCOUNT_FENCE_ACQ() atomic_thread_fence_acq() 132 #define VNODE_REFCOUNT_FENCE_REL() atomic_thread_fence_rel() 133 #else 134 #define VNODE_REFCOUNT_FENCE_ACQ() 135 #define VNODE_REFCOUNT_FENCE_REL() 136 #endif 137 138 /* 139 * Number of vnodes in existence. Increased whenever getnewvnode() 140 * allocates a new vnode, decreased in vdropl() for VI_DOOMED vnode. 141 */ 142 static unsigned long numvnodes; 143 144 SYSCTL_ULONG(_vfs, OID_AUTO, numvnodes, CTLFLAG_RD, &numvnodes, 0, 145 "Number of vnodes in existence"); 146 147 static counter_u64_t vnodes_created; 148 SYSCTL_COUNTER_U64(_vfs, OID_AUTO, vnodes_created, CTLFLAG_RD, &vnodes_created, 149 "Number of vnodes created by getnewvnode"); 150 151 static u_long mnt_free_list_batch = 128; 152 SYSCTL_ULONG(_vfs, OID_AUTO, mnt_free_list_batch, CTLFLAG_RW, 153 &mnt_free_list_batch, 0, "Limit of vnodes held on mnt's free list"); 154 155 /* 156 * Conversion tables for conversion from vnode types to inode formats 157 * and back. 158 */ 159 enum vtype iftovt_tab[16] = { 160 VNON, VFIFO, VCHR, VNON, VDIR, VNON, VBLK, VNON, 161 VREG, VNON, VLNK, VNON, VSOCK, VNON, VNON, VNON 162 }; 163 int vttoif_tab[10] = { 164 0, S_IFREG, S_IFDIR, S_IFBLK, S_IFCHR, S_IFLNK, 165 S_IFSOCK, S_IFIFO, S_IFMT, S_IFMT 166 }; 167 168 /* 169 * List of vnodes that are ready for recycling. 170 */ 171 static TAILQ_HEAD(freelst, vnode) vnode_free_list; 172 173 /* 174 * "Free" vnode target. Free vnodes are rarely completely free, but are 175 * just ones that are cheap to recycle. Usually they are for files which 176 * have been stat'd but not read; these usually have inode and namecache 177 * data attached to them. This target is the preferred minimum size of a 178 * sub-cache consisting mostly of such files. The system balances the size 179 * of this sub-cache with its complement to try to prevent either from 180 * thrashing while the other is relatively inactive. The targets express 181 * a preference for the best balance. 182 * 183 * "Above" this target there are 2 further targets (watermarks) related 184 * to recyling of free vnodes. In the best-operating case, the cache is 185 * exactly full, the free list has size between vlowat and vhiwat above the 186 * free target, and recycling from it and normal use maintains this state. 187 * Sometimes the free list is below vlowat or even empty, but this state 188 * is even better for immediate use provided the cache is not full. 189 * Otherwise, vnlru_proc() runs to reclaim enough vnodes (usually non-free 190 * ones) to reach one of these states. The watermarks are currently hard- 191 * coded as 4% and 9% of the available space higher. These and the default 192 * of 25% for wantfreevnodes are too large if the memory size is large. 193 * E.g., 9% of 75% of MAXVNODES is more than 566000 vnodes to reclaim 194 * whenever vnlru_proc() becomes active. 195 */ 196 static u_long wantfreevnodes; 197 SYSCTL_ULONG(_vfs, OID_AUTO, wantfreevnodes, CTLFLAG_RW, 198 &wantfreevnodes, 0, "Target for minimum number of \"free\" vnodes"); 199 static u_long freevnodes; 200 SYSCTL_ULONG(_vfs, OID_AUTO, freevnodes, CTLFLAG_RD, 201 &freevnodes, 0, "Number of \"free\" vnodes"); 202 203 static counter_u64_t recycles_count; 204 SYSCTL_COUNTER_U64(_vfs, OID_AUTO, recycles, CTLFLAG_RD, &recycles_count, 205 "Number of vnodes recycled to meet vnode cache targets"); 206 207 /* 208 * Various variables used for debugging the new implementation of 209 * reassignbuf(). 210 * XXX these are probably of (very) limited utility now. 211 */ 212 static int reassignbufcalls; 213 SYSCTL_INT(_vfs, OID_AUTO, reassignbufcalls, CTLFLAG_RW, &reassignbufcalls, 0, 214 "Number of calls to reassignbuf"); 215 216 static counter_u64_t free_owe_inact; 217 SYSCTL_COUNTER_U64(_vfs, OID_AUTO, free_owe_inact, CTLFLAG_RD, &free_owe_inact, 218 "Number of times free vnodes kept on active list due to VFS " 219 "owing inactivation"); 220 221 /* To keep more than one thread at a time from running vfs_getnewfsid */ 222 static struct mtx mntid_mtx; 223 224 /* 225 * Lock for any access to the following: 226 * vnode_free_list 227 * numvnodes 228 * freevnodes 229 */ 230 static struct mtx vnode_free_list_mtx; 231 232 /* Publicly exported FS */ 233 struct nfs_public nfs_pub; 234 235 static uma_zone_t buf_trie_zone; 236 237 /* Zone for allocation of new vnodes - used exclusively by getnewvnode() */ 238 static uma_zone_t vnode_zone; 239 static uma_zone_t vnodepoll_zone; 240 241 /* 242 * The workitem queue. 243 * 244 * It is useful to delay writes of file data and filesystem metadata 245 * for tens of seconds so that quickly created and deleted files need 246 * not waste disk bandwidth being created and removed. To realize this, 247 * we append vnodes to a "workitem" queue. When running with a soft 248 * updates implementation, most pending metadata dependencies should 249 * not wait for more than a few seconds. Thus, mounted on block devices 250 * are delayed only about a half the time that file data is delayed. 251 * Similarly, directory updates are more critical, so are only delayed 252 * about a third the time that file data is delayed. Thus, there are 253 * SYNCER_MAXDELAY queues that are processed round-robin at a rate of 254 * one each second (driven off the filesystem syncer process). The 255 * syncer_delayno variable indicates the next queue that is to be processed. 256 * Items that need to be processed soon are placed in this queue: 257 * 258 * syncer_workitem_pending[syncer_delayno] 259 * 260 * A delay of fifteen seconds is done by placing the request fifteen 261 * entries later in the queue: 262 * 263 * syncer_workitem_pending[(syncer_delayno + 15) & syncer_mask] 264 * 265 */ 266 static int syncer_delayno; 267 static long syncer_mask; 268 LIST_HEAD(synclist, bufobj); 269 static struct synclist *syncer_workitem_pending; 270 /* 271 * The sync_mtx protects: 272 * bo->bo_synclist 273 * sync_vnode_count 274 * syncer_delayno 275 * syncer_state 276 * syncer_workitem_pending 277 * syncer_worklist_len 278 * rushjob 279 */ 280 static struct mtx sync_mtx; 281 static struct cv sync_wakeup; 282 283 #define SYNCER_MAXDELAY 32 284 static int syncer_maxdelay = SYNCER_MAXDELAY; /* maximum delay time */ 285 static int syncdelay = 30; /* max time to delay syncing data */ 286 static int filedelay = 30; /* time to delay syncing files */ 287 SYSCTL_INT(_kern, OID_AUTO, filedelay, CTLFLAG_RW, &filedelay, 0, 288 "Time to delay syncing files (in seconds)"); 289 static int dirdelay = 29; /* time to delay syncing directories */ 290 SYSCTL_INT(_kern, OID_AUTO, dirdelay, CTLFLAG_RW, &dirdelay, 0, 291 "Time to delay syncing directories (in seconds)"); 292 static int metadelay = 28; /* time to delay syncing metadata */ 293 SYSCTL_INT(_kern, OID_AUTO, metadelay, CTLFLAG_RW, &metadelay, 0, 294 "Time to delay syncing metadata (in seconds)"); 295 static int rushjob; /* number of slots to run ASAP */ 296 static int stat_rush_requests; /* number of times I/O speeded up */ 297 SYSCTL_INT(_debug, OID_AUTO, rush_requests, CTLFLAG_RW, &stat_rush_requests, 0, 298 "Number of times I/O speeded up (rush requests)"); 299 300 /* 301 * When shutting down the syncer, run it at four times normal speed. 302 */ 303 #define SYNCER_SHUTDOWN_SPEEDUP 4 304 static int sync_vnode_count; 305 static int syncer_worklist_len; 306 static enum { SYNCER_RUNNING, SYNCER_SHUTTING_DOWN, SYNCER_FINAL_DELAY } 307 syncer_state; 308 309 /* Target for maximum number of vnodes. */ 310 int desiredvnodes; 311 static int gapvnodes; /* gap between wanted and desired */ 312 static int vhiwat; /* enough extras after expansion */ 313 static int vlowat; /* minimal extras before expansion */ 314 static int vstir; /* nonzero to stir non-free vnodes */ 315 static volatile int vsmalltrigger = 8; /* pref to keep if > this many pages */ 316 317 static int 318 sysctl_update_desiredvnodes(SYSCTL_HANDLER_ARGS) 319 { 320 int error, old_desiredvnodes; 321 322 old_desiredvnodes = desiredvnodes; 323 if ((error = sysctl_handle_int(oidp, arg1, arg2, req)) != 0) 324 return (error); 325 if (old_desiredvnodes != desiredvnodes) { 326 wantfreevnodes = desiredvnodes / 4; 327 /* XXX locking seems to be incomplete. */ 328 vfs_hash_changesize(desiredvnodes); 329 cache_changesize(desiredvnodes); 330 } 331 return (0); 332 } 333 334 SYSCTL_PROC(_kern, KERN_MAXVNODES, maxvnodes, 335 CTLTYPE_INT | CTLFLAG_MPSAFE | CTLFLAG_RW, &desiredvnodes, 0, 336 sysctl_update_desiredvnodes, "I", "Target for maximum number of vnodes"); 337 SYSCTL_ULONG(_kern, OID_AUTO, minvnodes, CTLFLAG_RW, 338 &wantfreevnodes, 0, "Old name for vfs.wantfreevnodes (legacy)"); 339 static int vnlru_nowhere; 340 SYSCTL_INT(_debug, OID_AUTO, vnlru_nowhere, CTLFLAG_RW, 341 &vnlru_nowhere, 0, "Number of times the vnlru process ran without success"); 342 343 static int 344 sysctl_try_reclaim_vnode(SYSCTL_HANDLER_ARGS) 345 { 346 struct vnode *vp; 347 struct nameidata nd; 348 char *buf; 349 unsigned long ndflags; 350 int error; 351 352 if (req->newptr == NULL) 353 return (EINVAL); 354 if (req->newlen > PATH_MAX) 355 return (E2BIG); 356 357 buf = malloc(PATH_MAX + 1, M_TEMP, M_WAITOK); 358 error = SYSCTL_IN(req, buf, req->newlen); 359 if (error != 0) 360 goto out; 361 362 buf[req->newlen] = '\0'; 363 364 ndflags = LOCKLEAF | NOFOLLOW | AUDITVNODE1 | NOCACHE | SAVENAME; 365 NDINIT(&nd, LOOKUP, ndflags, UIO_SYSSPACE, buf, curthread); 366 if ((error = namei(&nd)) != 0) 367 goto out; 368 vp = nd.ni_vp; 369 370 if ((vp->v_iflag & VI_DOOMED) != 0) { 371 /* 372 * This vnode is being recycled. Return != 0 to let the caller 373 * know that the sysctl had no effect. Return EAGAIN because a 374 * subsequent call will likely succeed (since namei will create 375 * a new vnode if necessary) 376 */ 377 error = EAGAIN; 378 goto putvnode; 379 } 380 381 counter_u64_add(recycles_count, 1); 382 vgone(vp); 383 putvnode: 384 NDFREE(&nd, 0); 385 out: 386 free(buf, M_TEMP); 387 return (error); 388 } 389 390 static int 391 sysctl_ftry_reclaim_vnode(SYSCTL_HANDLER_ARGS) 392 { 393 struct thread *td = curthread; 394 struct vnode *vp; 395 struct file *fp; 396 int error; 397 int fd; 398 399 if (req->newptr == NULL) 400 return (EBADF); 401 402 error = sysctl_handle_int(oidp, &fd, 0, req); 403 if (error != 0) 404 return (error); 405 error = getvnode(curthread, fd, &cap_fcntl_rights, &fp); 406 if (error != 0) 407 return (error); 408 vp = fp->f_vnode; 409 410 error = vn_lock(vp, LK_EXCLUSIVE); 411 if (error != 0) 412 goto drop; 413 414 counter_u64_add(recycles_count, 1); 415 vgone(vp); 416 VOP_UNLOCK(vp, 0); 417 drop: 418 fdrop(fp, td); 419 return (error); 420 } 421 422 SYSCTL_PROC(_debug, OID_AUTO, try_reclaim_vnode, 423 CTLTYPE_STRING | CTLFLAG_MPSAFE | CTLFLAG_WR, NULL, 0, 424 sysctl_try_reclaim_vnode, "A", "Try to reclaim a vnode by its pathname"); 425 SYSCTL_PROC(_debug, OID_AUTO, ftry_reclaim_vnode, 426 CTLTYPE_INT | CTLFLAG_MPSAFE | CTLFLAG_WR, NULL, 0, 427 sysctl_ftry_reclaim_vnode, "I", 428 "Try to reclaim a vnode by its file descriptor"); 429 430 /* Shift count for (uintptr_t)vp to initialize vp->v_hash. */ 431 static int vnsz2log; 432 433 /* 434 * Support for the bufobj clean & dirty pctrie. 435 */ 436 static void * 437 buf_trie_alloc(struct pctrie *ptree) 438 { 439 440 return uma_zalloc(buf_trie_zone, M_NOWAIT); 441 } 442 443 static void 444 buf_trie_free(struct pctrie *ptree, void *node) 445 { 446 447 uma_zfree(buf_trie_zone, node); 448 } 449 PCTRIE_DEFINE(BUF, buf, b_lblkno, buf_trie_alloc, buf_trie_free); 450 451 /* 452 * Initialize the vnode management data structures. 453 * 454 * Reevaluate the following cap on the number of vnodes after the physical 455 * memory size exceeds 512GB. In the limit, as the physical memory size 456 * grows, the ratio of the memory size in KB to vnodes approaches 64:1. 457 */ 458 #ifndef MAXVNODES_MAX 459 #define MAXVNODES_MAX (512 * 1024 * 1024 / 64) /* 8M */ 460 #endif 461 462 /* 463 * Initialize a vnode as it first enters the zone. 464 */ 465 static int 466 vnode_init(void *mem, int size, int flags) 467 { 468 struct vnode *vp; 469 470 vp = mem; 471 bzero(vp, size); 472 /* 473 * Setup locks. 474 */ 475 vp->v_vnlock = &vp->v_lock; 476 mtx_init(&vp->v_interlock, "vnode interlock", NULL, MTX_DEF); 477 /* 478 * By default, don't allow shared locks unless filesystems opt-in. 479 */ 480 lockinit(vp->v_vnlock, PVFS, "vnode", VLKTIMEOUT, 481 LK_NOSHARE | LK_IS_VNODE); 482 /* 483 * Initialize bufobj. 484 */ 485 bufobj_init(&vp->v_bufobj, vp); 486 /* 487 * Initialize namecache. 488 */ 489 LIST_INIT(&vp->v_cache_src); 490 TAILQ_INIT(&vp->v_cache_dst); 491 /* 492 * Initialize rangelocks. 493 */ 494 rangelock_init(&vp->v_rl); 495 return (0); 496 } 497 498 /* 499 * Free a vnode when it is cleared from the zone. 500 */ 501 static void 502 vnode_fini(void *mem, int size) 503 { 504 struct vnode *vp; 505 struct bufobj *bo; 506 507 vp = mem; 508 rangelock_destroy(&vp->v_rl); 509 lockdestroy(vp->v_vnlock); 510 mtx_destroy(&vp->v_interlock); 511 bo = &vp->v_bufobj; 512 rw_destroy(BO_LOCKPTR(bo)); 513 } 514 515 /* 516 * Provide the size of NFS nclnode and NFS fh for calculation of the 517 * vnode memory consumption. The size is specified directly to 518 * eliminate dependency on NFS-private header. 519 * 520 * Other filesystems may use bigger or smaller (like UFS and ZFS) 521 * private inode data, but the NFS-based estimation is ample enough. 522 * Still, we care about differences in the size between 64- and 32-bit 523 * platforms. 524 * 525 * Namecache structure size is heuristically 526 * sizeof(struct namecache_ts) + CACHE_PATH_CUTOFF + 1. 527 */ 528 #ifdef _LP64 529 #define NFS_NCLNODE_SZ (528 + 64) 530 #define NC_SZ 148 531 #else 532 #define NFS_NCLNODE_SZ (360 + 32) 533 #define NC_SZ 92 534 #endif 535 536 static void 537 vntblinit(void *dummy __unused) 538 { 539 u_int i; 540 int physvnodes, virtvnodes; 541 542 /* 543 * Desiredvnodes is a function of the physical memory size and the 544 * kernel's heap size. Generally speaking, it scales with the 545 * physical memory size. The ratio of desiredvnodes to the physical 546 * memory size is 1:16 until desiredvnodes exceeds 98,304. 547 * Thereafter, the 548 * marginal ratio of desiredvnodes to the physical memory size is 549 * 1:64. However, desiredvnodes is limited by the kernel's heap 550 * size. The memory required by desiredvnodes vnodes and vm objects 551 * must not exceed 1/10th of the kernel's heap size. 552 */ 553 physvnodes = maxproc + pgtok(vm_cnt.v_page_count) / 64 + 554 3 * min(98304 * 16, pgtok(vm_cnt.v_page_count)) / 64; 555 virtvnodes = vm_kmem_size / (10 * (sizeof(struct vm_object) + 556 sizeof(struct vnode) + NC_SZ * ncsizefactor + NFS_NCLNODE_SZ)); 557 desiredvnodes = min(physvnodes, virtvnodes); 558 if (desiredvnodes > MAXVNODES_MAX) { 559 if (bootverbose) 560 printf("Reducing kern.maxvnodes %d -> %d\n", 561 desiredvnodes, MAXVNODES_MAX); 562 desiredvnodes = MAXVNODES_MAX; 563 } 564 wantfreevnodes = desiredvnodes / 4; 565 mtx_init(&mntid_mtx, "mntid", NULL, MTX_DEF); 566 TAILQ_INIT(&vnode_free_list); 567 mtx_init(&vnode_free_list_mtx, "vnode_free_list", NULL, MTX_DEF); 568 vnode_zone = uma_zcreate("VNODE", sizeof (struct vnode), NULL, NULL, 569 vnode_init, vnode_fini, UMA_ALIGN_PTR, 0); 570 vnodepoll_zone = uma_zcreate("VNODEPOLL", sizeof (struct vpollinfo), 571 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); 572 /* 573 * Preallocate enough nodes to support one-per buf so that 574 * we can not fail an insert. reassignbuf() callers can not 575 * tolerate the insertion failure. 576 */ 577 buf_trie_zone = uma_zcreate("BUF TRIE", pctrie_node_size(), 578 NULL, NULL, pctrie_zone_init, NULL, UMA_ALIGN_PTR, 579 UMA_ZONE_NOFREE | UMA_ZONE_VM); 580 uma_prealloc(buf_trie_zone, nbuf); 581 582 vnodes_created = counter_u64_alloc(M_WAITOK); 583 recycles_count = counter_u64_alloc(M_WAITOK); 584 free_owe_inact = counter_u64_alloc(M_WAITOK); 585 586 /* 587 * Initialize the filesystem syncer. 588 */ 589 syncer_workitem_pending = hashinit(syncer_maxdelay, M_VNODE, 590 &syncer_mask); 591 syncer_maxdelay = syncer_mask + 1; 592 mtx_init(&sync_mtx, "Syncer mtx", NULL, MTX_DEF); 593 cv_init(&sync_wakeup, "syncer"); 594 for (i = 1; i <= sizeof(struct vnode); i <<= 1) 595 vnsz2log++; 596 vnsz2log--; 597 } 598 SYSINIT(vfs, SI_SUB_VFS, SI_ORDER_FIRST, vntblinit, NULL); 599 600 601 /* 602 * Mark a mount point as busy. Used to synchronize access and to delay 603 * unmounting. Eventually, mountlist_mtx is not released on failure. 604 * 605 * vfs_busy() is a custom lock, it can block the caller. 606 * vfs_busy() only sleeps if the unmount is active on the mount point. 607 * For a mountpoint mp, vfs_busy-enforced lock is before lock of any 608 * vnode belonging to mp. 609 * 610 * Lookup uses vfs_busy() to traverse mount points. 611 * root fs var fs 612 * / vnode lock A / vnode lock (/var) D 613 * /var vnode lock B /log vnode lock(/var/log) E 614 * vfs_busy lock C vfs_busy lock F 615 * 616 * Within each file system, the lock order is C->A->B and F->D->E. 617 * 618 * When traversing across mounts, the system follows that lock order: 619 * 620 * C->A->B 621 * | 622 * +->F->D->E 623 * 624 * The lookup() process for namei("/var") illustrates the process: 625 * VOP_LOOKUP() obtains B while A is held 626 * vfs_busy() obtains a shared lock on F while A and B are held 627 * vput() releases lock on B 628 * vput() releases lock on A 629 * VFS_ROOT() obtains lock on D while shared lock on F is held 630 * vfs_unbusy() releases shared lock on F 631 * vn_lock() obtains lock on deadfs vnode vp_crossmp instead of A. 632 * Attempt to lock A (instead of vp_crossmp) while D is held would 633 * violate the global order, causing deadlocks. 634 * 635 * dounmount() locks B while F is drained. 636 */ 637 int 638 vfs_busy(struct mount *mp, int flags) 639 { 640 641 MPASS((flags & ~MBF_MASK) == 0); 642 CTR3(KTR_VFS, "%s: mp %p with flags %d", __func__, mp, flags); 643 644 MNT_ILOCK(mp); 645 MNT_REF(mp); 646 /* 647 * If mount point is currently being unmounted, sleep until the 648 * mount point fate is decided. If thread doing the unmounting fails, 649 * it will clear MNTK_UNMOUNT flag before waking us up, indicating 650 * that this mount point has survived the unmount attempt and vfs_busy 651 * should retry. Otherwise the unmounter thread will set MNTK_REFEXPIRE 652 * flag in addition to MNTK_UNMOUNT, indicating that mount point is 653 * about to be really destroyed. vfs_busy needs to release its 654 * reference on the mount point in this case and return with ENOENT, 655 * telling the caller that mount mount it tried to busy is no longer 656 * valid. 657 */ 658 while (mp->mnt_kern_flag & MNTK_UNMOUNT) { 659 if (flags & MBF_NOWAIT || mp->mnt_kern_flag & MNTK_REFEXPIRE) { 660 MNT_REL(mp); 661 MNT_IUNLOCK(mp); 662 CTR1(KTR_VFS, "%s: failed busying before sleeping", 663 __func__); 664 return (ENOENT); 665 } 666 if (flags & MBF_MNTLSTLOCK) 667 mtx_unlock(&mountlist_mtx); 668 mp->mnt_kern_flag |= MNTK_MWAIT; 669 msleep(mp, MNT_MTX(mp), PVFS | PDROP, "vfs_busy", 0); 670 if (flags & MBF_MNTLSTLOCK) 671 mtx_lock(&mountlist_mtx); 672 MNT_ILOCK(mp); 673 } 674 if (flags & MBF_MNTLSTLOCK) 675 mtx_unlock(&mountlist_mtx); 676 mp->mnt_lockref++; 677 MNT_IUNLOCK(mp); 678 return (0); 679 } 680 681 /* 682 * Free a busy filesystem. 683 */ 684 void 685 vfs_unbusy(struct mount *mp) 686 { 687 688 CTR2(KTR_VFS, "%s: mp %p", __func__, mp); 689 MNT_ILOCK(mp); 690 MNT_REL(mp); 691 KASSERT(mp->mnt_lockref > 0, ("negative mnt_lockref")); 692 mp->mnt_lockref--; 693 if (mp->mnt_lockref == 0 && (mp->mnt_kern_flag & MNTK_DRAINING) != 0) { 694 MPASS(mp->mnt_kern_flag & MNTK_UNMOUNT); 695 CTR1(KTR_VFS, "%s: waking up waiters", __func__); 696 mp->mnt_kern_flag &= ~MNTK_DRAINING; 697 wakeup(&mp->mnt_lockref); 698 } 699 MNT_IUNLOCK(mp); 700 } 701 702 /* 703 * Lookup a mount point by filesystem identifier. 704 */ 705 struct mount * 706 vfs_getvfs(fsid_t *fsid) 707 { 708 struct mount *mp; 709 710 CTR2(KTR_VFS, "%s: fsid %p", __func__, fsid); 711 mtx_lock(&mountlist_mtx); 712 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 713 if (mp->mnt_stat.f_fsid.val[0] == fsid->val[0] && 714 mp->mnt_stat.f_fsid.val[1] == fsid->val[1]) { 715 vfs_ref(mp); 716 mtx_unlock(&mountlist_mtx); 717 return (mp); 718 } 719 } 720 mtx_unlock(&mountlist_mtx); 721 CTR2(KTR_VFS, "%s: lookup failed for %p id", __func__, fsid); 722 return ((struct mount *) 0); 723 } 724 725 /* 726 * Lookup a mount point by filesystem identifier, busying it before 727 * returning. 728 * 729 * To avoid congestion on mountlist_mtx, implement simple direct-mapped 730 * cache for popular filesystem identifiers. The cache is lockess, using 731 * the fact that struct mount's are never freed. In worst case we may 732 * get pointer to unmounted or even different filesystem, so we have to 733 * check what we got, and go slow way if so. 734 */ 735 struct mount * 736 vfs_busyfs(fsid_t *fsid) 737 { 738 #define FSID_CACHE_SIZE 256 739 typedef struct mount * volatile vmp_t; 740 static vmp_t cache[FSID_CACHE_SIZE]; 741 struct mount *mp; 742 int error; 743 uint32_t hash; 744 745 CTR2(KTR_VFS, "%s: fsid %p", __func__, fsid); 746 hash = fsid->val[0] ^ fsid->val[1]; 747 hash = (hash >> 16 ^ hash) & (FSID_CACHE_SIZE - 1); 748 mp = cache[hash]; 749 if (mp == NULL || 750 mp->mnt_stat.f_fsid.val[0] != fsid->val[0] || 751 mp->mnt_stat.f_fsid.val[1] != fsid->val[1]) 752 goto slow; 753 if (vfs_busy(mp, 0) != 0) { 754 cache[hash] = NULL; 755 goto slow; 756 } 757 if (mp->mnt_stat.f_fsid.val[0] == fsid->val[0] && 758 mp->mnt_stat.f_fsid.val[1] == fsid->val[1]) 759 return (mp); 760 else 761 vfs_unbusy(mp); 762 763 slow: 764 mtx_lock(&mountlist_mtx); 765 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 766 if (mp->mnt_stat.f_fsid.val[0] == fsid->val[0] && 767 mp->mnt_stat.f_fsid.val[1] == fsid->val[1]) { 768 error = vfs_busy(mp, MBF_MNTLSTLOCK); 769 if (error) { 770 cache[hash] = NULL; 771 mtx_unlock(&mountlist_mtx); 772 return (NULL); 773 } 774 cache[hash] = mp; 775 return (mp); 776 } 777 } 778 CTR2(KTR_VFS, "%s: lookup failed for %p id", __func__, fsid); 779 mtx_unlock(&mountlist_mtx); 780 return ((struct mount *) 0); 781 } 782 783 /* 784 * Check if a user can access privileged mount options. 785 */ 786 int 787 vfs_suser(struct mount *mp, struct thread *td) 788 { 789 int error; 790 791 if (jailed(td->td_ucred)) { 792 /* 793 * If the jail of the calling thread lacks permission for 794 * this type of file system, deny immediately. 795 */ 796 if (!prison_allow(td->td_ucred, mp->mnt_vfc->vfc_prison_flag)) 797 return (EPERM); 798 799 /* 800 * If the file system was mounted outside the jail of the 801 * calling thread, deny immediately. 802 */ 803 if (prison_check(td->td_ucred, mp->mnt_cred) != 0) 804 return (EPERM); 805 } 806 807 /* 808 * If file system supports delegated administration, we don't check 809 * for the PRIV_VFS_MOUNT_OWNER privilege - it will be better verified 810 * by the file system itself. 811 * If this is not the user that did original mount, we check for 812 * the PRIV_VFS_MOUNT_OWNER privilege. 813 */ 814 if (!(mp->mnt_vfc->vfc_flags & VFCF_DELEGADMIN) && 815 mp->mnt_cred->cr_uid != td->td_ucred->cr_uid) { 816 if ((error = priv_check(td, PRIV_VFS_MOUNT_OWNER)) != 0) 817 return (error); 818 } 819 return (0); 820 } 821 822 /* 823 * Get a new unique fsid. Try to make its val[0] unique, since this value 824 * will be used to create fake device numbers for stat(). Also try (but 825 * not so hard) make its val[0] unique mod 2^16, since some emulators only 826 * support 16-bit device numbers. We end up with unique val[0]'s for the 827 * first 2^16 calls and unique val[0]'s mod 2^16 for the first 2^8 calls. 828 * 829 * Keep in mind that several mounts may be running in parallel. Starting 830 * the search one past where the previous search terminated is both a 831 * micro-optimization and a defense against returning the same fsid to 832 * different mounts. 833 */ 834 void 835 vfs_getnewfsid(struct mount *mp) 836 { 837 static uint16_t mntid_base; 838 struct mount *nmp; 839 fsid_t tfsid; 840 int mtype; 841 842 CTR2(KTR_VFS, "%s: mp %p", __func__, mp); 843 mtx_lock(&mntid_mtx); 844 mtype = mp->mnt_vfc->vfc_typenum; 845 tfsid.val[1] = mtype; 846 mtype = (mtype & 0xFF) << 24; 847 for (;;) { 848 tfsid.val[0] = makedev(255, 849 mtype | ((mntid_base & 0xFF00) << 8) | (mntid_base & 0xFF)); 850 mntid_base++; 851 if ((nmp = vfs_getvfs(&tfsid)) == NULL) 852 break; 853 vfs_rel(nmp); 854 } 855 mp->mnt_stat.f_fsid.val[0] = tfsid.val[0]; 856 mp->mnt_stat.f_fsid.val[1] = tfsid.val[1]; 857 mtx_unlock(&mntid_mtx); 858 } 859 860 /* 861 * Knob to control the precision of file timestamps: 862 * 863 * 0 = seconds only; nanoseconds zeroed. 864 * 1 = seconds and nanoseconds, accurate within 1/HZ. 865 * 2 = seconds and nanoseconds, truncated to microseconds. 866 * >=3 = seconds and nanoseconds, maximum precision. 867 */ 868 enum { TSP_SEC, TSP_HZ, TSP_USEC, TSP_NSEC }; 869 870 static int timestamp_precision = TSP_USEC; 871 SYSCTL_INT(_vfs, OID_AUTO, timestamp_precision, CTLFLAG_RW, 872 ×tamp_precision, 0, "File timestamp precision (0: seconds, " 873 "1: sec + ns accurate to 1/HZ, 2: sec + ns truncated to us, " 874 "3+: sec + ns (max. precision))"); 875 876 /* 877 * Get a current timestamp. 878 */ 879 void 880 vfs_timestamp(struct timespec *tsp) 881 { 882 struct timeval tv; 883 884 switch (timestamp_precision) { 885 case TSP_SEC: 886 tsp->tv_sec = time_second; 887 tsp->tv_nsec = 0; 888 break; 889 case TSP_HZ: 890 getnanotime(tsp); 891 break; 892 case TSP_USEC: 893 microtime(&tv); 894 TIMEVAL_TO_TIMESPEC(&tv, tsp); 895 break; 896 case TSP_NSEC: 897 default: 898 nanotime(tsp); 899 break; 900 } 901 } 902 903 /* 904 * Set vnode attributes to VNOVAL 905 */ 906 void 907 vattr_null(struct vattr *vap) 908 { 909 910 vap->va_type = VNON; 911 vap->va_size = VNOVAL; 912 vap->va_bytes = VNOVAL; 913 vap->va_mode = VNOVAL; 914 vap->va_nlink = VNOVAL; 915 vap->va_uid = VNOVAL; 916 vap->va_gid = VNOVAL; 917 vap->va_fsid = VNOVAL; 918 vap->va_fileid = VNOVAL; 919 vap->va_blocksize = VNOVAL; 920 vap->va_rdev = VNOVAL; 921 vap->va_atime.tv_sec = VNOVAL; 922 vap->va_atime.tv_nsec = VNOVAL; 923 vap->va_mtime.tv_sec = VNOVAL; 924 vap->va_mtime.tv_nsec = VNOVAL; 925 vap->va_ctime.tv_sec = VNOVAL; 926 vap->va_ctime.tv_nsec = VNOVAL; 927 vap->va_birthtime.tv_sec = VNOVAL; 928 vap->va_birthtime.tv_nsec = VNOVAL; 929 vap->va_flags = VNOVAL; 930 vap->va_gen = VNOVAL; 931 vap->va_vaflags = 0; 932 } 933 934 /* 935 * This routine is called when we have too many vnodes. It attempts 936 * to free <count> vnodes and will potentially free vnodes that still 937 * have VM backing store (VM backing store is typically the cause 938 * of a vnode blowout so we want to do this). Therefore, this operation 939 * is not considered cheap. 940 * 941 * A number of conditions may prevent a vnode from being reclaimed. 942 * the buffer cache may have references on the vnode, a directory 943 * vnode may still have references due to the namei cache representing 944 * underlying files, or the vnode may be in active use. It is not 945 * desirable to reuse such vnodes. These conditions may cause the 946 * number of vnodes to reach some minimum value regardless of what 947 * you set kern.maxvnodes to. Do not set kern.maxvnodes too low. 948 * 949 * @param mp Try to reclaim vnodes from this mountpoint 950 * @param reclaim_nc_src Only reclaim directories with outgoing namecache 951 * entries if this argument is strue 952 * @param trigger Only reclaim vnodes with fewer than this many resident 953 * pages. 954 * @return The number of vnodes that were reclaimed. 955 */ 956 static int 957 vlrureclaim(struct mount *mp, bool reclaim_nc_src, int trigger) 958 { 959 struct vnode *vp; 960 int count, done, target; 961 962 done = 0; 963 vn_start_write(NULL, &mp, V_WAIT); 964 MNT_ILOCK(mp); 965 count = mp->mnt_nvnodelistsize; 966 target = count * (int64_t)gapvnodes / imax(desiredvnodes, 1); 967 target = target / 10 + 1; 968 while (count != 0 && done < target) { 969 vp = TAILQ_FIRST(&mp->mnt_nvnodelist); 970 while (vp != NULL && vp->v_type == VMARKER) 971 vp = TAILQ_NEXT(vp, v_nmntvnodes); 972 if (vp == NULL) 973 break; 974 /* 975 * XXX LRU is completely broken for non-free vnodes. First 976 * by calling here in mountpoint order, then by moving 977 * unselected vnodes to the end here, and most grossly by 978 * removing the vlruvp() function that was supposed to 979 * maintain the order. (This function was born broken 980 * since syncer problems prevented it doing anything.) The 981 * order is closer to LRC (C = Created). 982 * 983 * LRU reclaiming of vnodes seems to have last worked in 984 * FreeBSD-3 where LRU wasn't mentioned under any spelling. 985 * Then there was no hold count, and inactive vnodes were 986 * simply put on the free list in LRU order. The separate 987 * lists also break LRU. We prefer to reclaim from the 988 * free list for technical reasons. This tends to thrash 989 * the free list to keep very unrecently used held vnodes. 990 * The problem is mitigated by keeping the free list large. 991 */ 992 TAILQ_REMOVE(&mp->mnt_nvnodelist, vp, v_nmntvnodes); 993 TAILQ_INSERT_TAIL(&mp->mnt_nvnodelist, vp, v_nmntvnodes); 994 --count; 995 if (!VI_TRYLOCK(vp)) 996 goto next_iter; 997 /* 998 * If it's been deconstructed already, it's still 999 * referenced, or it exceeds the trigger, skip it. 1000 * Also skip free vnodes. We are trying to make space 1001 * to expand the free list, not reduce it. 1002 */ 1003 if (vp->v_usecount || 1004 (!reclaim_nc_src && !LIST_EMPTY(&vp->v_cache_src)) || 1005 ((vp->v_iflag & VI_FREE) != 0) || 1006 (vp->v_iflag & VI_DOOMED) != 0 || (vp->v_object != NULL && 1007 vp->v_object->resident_page_count > trigger)) { 1008 VI_UNLOCK(vp); 1009 goto next_iter; 1010 } 1011 MNT_IUNLOCK(mp); 1012 vholdl(vp); 1013 if (VOP_LOCK(vp, LK_INTERLOCK|LK_EXCLUSIVE|LK_NOWAIT)) { 1014 vdrop(vp); 1015 goto next_iter_mntunlocked; 1016 } 1017 VI_LOCK(vp); 1018 /* 1019 * v_usecount may have been bumped after VOP_LOCK() dropped 1020 * the vnode interlock and before it was locked again. 1021 * 1022 * It is not necessary to recheck VI_DOOMED because it can 1023 * only be set by another thread that holds both the vnode 1024 * lock and vnode interlock. If another thread has the 1025 * vnode lock before we get to VOP_LOCK() and obtains the 1026 * vnode interlock after VOP_LOCK() drops the vnode 1027 * interlock, the other thread will be unable to drop the 1028 * vnode lock before our VOP_LOCK() call fails. 1029 */ 1030 if (vp->v_usecount || 1031 (!reclaim_nc_src && !LIST_EMPTY(&vp->v_cache_src)) || 1032 (vp->v_iflag & VI_FREE) != 0 || 1033 (vp->v_object != NULL && 1034 vp->v_object->resident_page_count > trigger)) { 1035 VOP_UNLOCK(vp, 0); 1036 vdropl(vp); 1037 goto next_iter_mntunlocked; 1038 } 1039 KASSERT((vp->v_iflag & VI_DOOMED) == 0, 1040 ("VI_DOOMED unexpectedly detected in vlrureclaim()")); 1041 counter_u64_add(recycles_count, 1); 1042 vgonel(vp); 1043 VOP_UNLOCK(vp, 0); 1044 vdropl(vp); 1045 done++; 1046 next_iter_mntunlocked: 1047 if (!should_yield()) 1048 goto relock_mnt; 1049 goto yield; 1050 next_iter: 1051 if (!should_yield()) 1052 continue; 1053 MNT_IUNLOCK(mp); 1054 yield: 1055 kern_yield(PRI_USER); 1056 relock_mnt: 1057 MNT_ILOCK(mp); 1058 } 1059 MNT_IUNLOCK(mp); 1060 vn_finished_write(mp); 1061 return done; 1062 } 1063 1064 static int max_vnlru_free = 10000; /* limit on vnode free requests per call */ 1065 SYSCTL_INT(_debug, OID_AUTO, max_vnlru_free, CTLFLAG_RW, &max_vnlru_free, 1066 0, 1067 "limit on vnode free requests per call to the vnlru_free routine"); 1068 1069 /* 1070 * Attempt to reduce the free list by the requested amount. 1071 */ 1072 static void 1073 vnlru_free_locked(int count, struct vfsops *mnt_op) 1074 { 1075 struct vnode *vp; 1076 struct mount *mp; 1077 bool tried_batches; 1078 1079 tried_batches = false; 1080 mtx_assert(&vnode_free_list_mtx, MA_OWNED); 1081 if (count > max_vnlru_free) 1082 count = max_vnlru_free; 1083 for (; count > 0; count--) { 1084 vp = TAILQ_FIRST(&vnode_free_list); 1085 /* 1086 * The list can be modified while the free_list_mtx 1087 * has been dropped and vp could be NULL here. 1088 */ 1089 if (vp == NULL) { 1090 if (tried_batches) 1091 break; 1092 mtx_unlock(&vnode_free_list_mtx); 1093 vnlru_return_batches(mnt_op); 1094 tried_batches = true; 1095 mtx_lock(&vnode_free_list_mtx); 1096 continue; 1097 } 1098 1099 VNASSERT(vp->v_op != NULL, vp, 1100 ("vnlru_free: vnode already reclaimed.")); 1101 KASSERT((vp->v_iflag & VI_FREE) != 0, 1102 ("Removing vnode not on freelist")); 1103 KASSERT((vp->v_iflag & VI_ACTIVE) == 0, 1104 ("Mangling active vnode")); 1105 1106 /* 1107 * Don't recycle if our vnode is from different type 1108 * of mount point. Note that mp is type-safe, the 1109 * check does not reach unmapped address even if 1110 * vnode is reclaimed. 1111 * Don't recycle if we can't get the interlock without 1112 * blocking. 1113 */ 1114 if ((mnt_op != NULL && (mp = vp->v_mount) != NULL && 1115 mp->mnt_op != mnt_op) || !VI_TRYLOCK(vp)) { 1116 continue; 1117 } 1118 VNASSERT((vp->v_iflag & VI_FREE) != 0 && vp->v_holdcnt == 0, 1119 vp, ("vp inconsistent on freelist")); 1120 1121 /* 1122 * The clear of VI_FREE prevents activation of the 1123 * vnode. There is no sense in putting the vnode on 1124 * the mount point active list, only to remove it 1125 * later during recycling. Inline the relevant part 1126 * of vholdl(), to avoid triggering assertions or 1127 * activating. 1128 */ 1129 freevnodes--; 1130 mtx_unlock(&vnode_free_list_mtx); 1131 vholdl(vp); 1132 VI_UNLOCK(vp); 1133 vtryrecycle(vp); 1134 /* 1135 * If the recycled succeeded this vdrop will actually free 1136 * the vnode. If not it will simply place it back on 1137 * the free list. 1138 */ 1139 vdrop(vp); 1140 mtx_lock(&vnode_free_list_mtx); 1141 } 1142 } 1143 1144 void 1145 vnlru_free(int count, struct vfsops *mnt_op) 1146 { 1147 1148 mtx_lock(&vnode_free_list_mtx); 1149 vnlru_free_locked(count, mnt_op); 1150 mtx_unlock(&vnode_free_list_mtx); 1151 } 1152 1153 1154 /* XXX some names and initialization are bad for limits and watermarks. */ 1155 static int 1156 vspace(void) 1157 { 1158 int space; 1159 1160 gapvnodes = imax(desiredvnodes - wantfreevnodes, 100); 1161 vhiwat = gapvnodes / 11; /* 9% -- just under the 10% in vlrureclaim() */ 1162 vlowat = vhiwat / 2; 1163 if (numvnodes > desiredvnodes) 1164 return (0); 1165 space = desiredvnodes - numvnodes; 1166 if (freevnodes > wantfreevnodes) 1167 space += freevnodes - wantfreevnodes; 1168 return (space); 1169 } 1170 1171 static void 1172 vnlru_return_batch_locked(struct mount *mp) 1173 { 1174 struct vnode *vp; 1175 1176 mtx_assert(&mp->mnt_listmtx, MA_OWNED); 1177 1178 if (mp->mnt_tmpfreevnodelistsize == 0) 1179 return; 1180 1181 TAILQ_FOREACH(vp, &mp->mnt_tmpfreevnodelist, v_actfreelist) { 1182 VNASSERT((vp->v_mflag & VMP_TMPMNTFREELIST) != 0, vp, 1183 ("vnode without VMP_TMPMNTFREELIST on mnt_tmpfreevnodelist")); 1184 vp->v_mflag &= ~VMP_TMPMNTFREELIST; 1185 } 1186 mtx_lock(&vnode_free_list_mtx); 1187 TAILQ_CONCAT(&vnode_free_list, &mp->mnt_tmpfreevnodelist, v_actfreelist); 1188 freevnodes += mp->mnt_tmpfreevnodelistsize; 1189 mtx_unlock(&vnode_free_list_mtx); 1190 mp->mnt_tmpfreevnodelistsize = 0; 1191 } 1192 1193 static void 1194 vnlru_return_batch(struct mount *mp) 1195 { 1196 1197 mtx_lock(&mp->mnt_listmtx); 1198 vnlru_return_batch_locked(mp); 1199 mtx_unlock(&mp->mnt_listmtx); 1200 } 1201 1202 static void 1203 vnlru_return_batches(struct vfsops *mnt_op) 1204 { 1205 struct mount *mp, *nmp; 1206 bool need_unbusy; 1207 1208 mtx_lock(&mountlist_mtx); 1209 for (mp = TAILQ_FIRST(&mountlist); mp != NULL; mp = nmp) { 1210 need_unbusy = false; 1211 if (mnt_op != NULL && mp->mnt_op != mnt_op) 1212 goto next; 1213 if (mp->mnt_tmpfreevnodelistsize == 0) 1214 goto next; 1215 if (vfs_busy(mp, MBF_NOWAIT | MBF_MNTLSTLOCK) == 0) { 1216 vnlru_return_batch(mp); 1217 need_unbusy = true; 1218 mtx_lock(&mountlist_mtx); 1219 } 1220 next: 1221 nmp = TAILQ_NEXT(mp, mnt_list); 1222 if (need_unbusy) 1223 vfs_unbusy(mp); 1224 } 1225 mtx_unlock(&mountlist_mtx); 1226 } 1227 1228 /* 1229 * Attempt to recycle vnodes in a context that is always safe to block. 1230 * Calling vlrurecycle() from the bowels of filesystem code has some 1231 * interesting deadlock problems. 1232 */ 1233 static struct proc *vnlruproc; 1234 static int vnlruproc_sig; 1235 1236 static void 1237 vnlru_proc(void) 1238 { 1239 struct mount *mp, *nmp; 1240 unsigned long onumvnodes; 1241 int done, force, trigger, usevnodes; 1242 bool reclaim_nc_src; 1243 1244 EVENTHANDLER_REGISTER(shutdown_pre_sync, kproc_shutdown, vnlruproc, 1245 SHUTDOWN_PRI_FIRST); 1246 1247 force = 0; 1248 for (;;) { 1249 kproc_suspend_check(vnlruproc); 1250 mtx_lock(&vnode_free_list_mtx); 1251 /* 1252 * If numvnodes is too large (due to desiredvnodes being 1253 * adjusted using its sysctl, or emergency growth), first 1254 * try to reduce it by discarding from the free list. 1255 */ 1256 if (numvnodes > desiredvnodes) 1257 vnlru_free_locked(numvnodes - desiredvnodes, NULL); 1258 /* 1259 * Sleep if the vnode cache is in a good state. This is 1260 * when it is not over-full and has space for about a 4% 1261 * or 9% expansion (by growing its size or inexcessively 1262 * reducing its free list). Otherwise, try to reclaim 1263 * space for a 10% expansion. 1264 */ 1265 if (vstir && force == 0) { 1266 force = 1; 1267 vstir = 0; 1268 } 1269 if (vspace() >= vlowat && force == 0) { 1270 vnlruproc_sig = 0; 1271 wakeup(&vnlruproc_sig); 1272 msleep(vnlruproc, &vnode_free_list_mtx, 1273 PVFS|PDROP, "vlruwt", hz); 1274 continue; 1275 } 1276 mtx_unlock(&vnode_free_list_mtx); 1277 done = 0; 1278 onumvnodes = numvnodes; 1279 /* 1280 * Calculate parameters for recycling. These are the same 1281 * throughout the loop to give some semblance of fairness. 1282 * The trigger point is to avoid recycling vnodes with lots 1283 * of resident pages. We aren't trying to free memory; we 1284 * are trying to recycle or at least free vnodes. 1285 */ 1286 if (numvnodes <= desiredvnodes) 1287 usevnodes = numvnodes - freevnodes; 1288 else 1289 usevnodes = numvnodes; 1290 if (usevnodes <= 0) 1291 usevnodes = 1; 1292 /* 1293 * The trigger value is is chosen to give a conservatively 1294 * large value to ensure that it alone doesn't prevent 1295 * making progress. The value can easily be so large that 1296 * it is effectively infinite in some congested and 1297 * misconfigured cases, and this is necessary. Normally 1298 * it is about 8 to 100 (pages), which is quite large. 1299 */ 1300 trigger = vm_cnt.v_page_count * 2 / usevnodes; 1301 if (force < 2) 1302 trigger = vsmalltrigger; 1303 reclaim_nc_src = force >= 3; 1304 mtx_lock(&mountlist_mtx); 1305 for (mp = TAILQ_FIRST(&mountlist); mp != NULL; mp = nmp) { 1306 if (vfs_busy(mp, MBF_NOWAIT | MBF_MNTLSTLOCK)) { 1307 nmp = TAILQ_NEXT(mp, mnt_list); 1308 continue; 1309 } 1310 done += vlrureclaim(mp, reclaim_nc_src, trigger); 1311 mtx_lock(&mountlist_mtx); 1312 nmp = TAILQ_NEXT(mp, mnt_list); 1313 vfs_unbusy(mp); 1314 } 1315 mtx_unlock(&mountlist_mtx); 1316 if (onumvnodes > desiredvnodes && numvnodes <= desiredvnodes) 1317 uma_reclaim(UMA_RECLAIM_DRAIN); 1318 if (done == 0) { 1319 if (force == 0 || force == 1) { 1320 force = 2; 1321 continue; 1322 } 1323 if (force == 2) { 1324 force = 3; 1325 continue; 1326 } 1327 force = 0; 1328 vnlru_nowhere++; 1329 tsleep(vnlruproc, PPAUSE, "vlrup", hz * 3); 1330 } else 1331 kern_yield(PRI_USER); 1332 /* 1333 * After becoming active to expand above low water, keep 1334 * active until above high water. 1335 */ 1336 force = vspace() < vhiwat; 1337 } 1338 } 1339 1340 static struct kproc_desc vnlru_kp = { 1341 "vnlru", 1342 vnlru_proc, 1343 &vnlruproc 1344 }; 1345 SYSINIT(vnlru, SI_SUB_KTHREAD_UPDATE, SI_ORDER_FIRST, kproc_start, 1346 &vnlru_kp); 1347 1348 /* 1349 * Routines having to do with the management of the vnode table. 1350 */ 1351 1352 /* 1353 * Try to recycle a freed vnode. We abort if anyone picks up a reference 1354 * before we actually vgone(). This function must be called with the vnode 1355 * held to prevent the vnode from being returned to the free list midway 1356 * through vgone(). 1357 */ 1358 static int 1359 vtryrecycle(struct vnode *vp) 1360 { 1361 struct mount *vnmp; 1362 1363 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 1364 VNASSERT(vp->v_holdcnt, vp, 1365 ("vtryrecycle: Recycling vp %p without a reference.", vp)); 1366 /* 1367 * This vnode may found and locked via some other list, if so we 1368 * can't recycle it yet. 1369 */ 1370 if (VOP_LOCK(vp, LK_EXCLUSIVE | LK_NOWAIT) != 0) { 1371 CTR2(KTR_VFS, 1372 "%s: impossible to recycle, vp %p lock is already held", 1373 __func__, vp); 1374 return (EWOULDBLOCK); 1375 } 1376 /* 1377 * Don't recycle if its filesystem is being suspended. 1378 */ 1379 if (vn_start_write(vp, &vnmp, V_NOWAIT) != 0) { 1380 VOP_UNLOCK(vp, 0); 1381 CTR2(KTR_VFS, 1382 "%s: impossible to recycle, cannot start the write for %p", 1383 __func__, vp); 1384 return (EBUSY); 1385 } 1386 /* 1387 * If we got this far, we need to acquire the interlock and see if 1388 * anyone picked up this vnode from another list. If not, we will 1389 * mark it with DOOMED via vgonel() so that anyone who does find it 1390 * will skip over it. 1391 */ 1392 VI_LOCK(vp); 1393 if (vp->v_usecount) { 1394 VOP_UNLOCK(vp, 0); 1395 VI_UNLOCK(vp); 1396 vn_finished_write(vnmp); 1397 CTR2(KTR_VFS, 1398 "%s: impossible to recycle, %p is already referenced", 1399 __func__, vp); 1400 return (EBUSY); 1401 } 1402 if ((vp->v_iflag & VI_DOOMED) == 0) { 1403 counter_u64_add(recycles_count, 1); 1404 vgonel(vp); 1405 } 1406 VOP_UNLOCK(vp, 0); 1407 VI_UNLOCK(vp); 1408 vn_finished_write(vnmp); 1409 return (0); 1410 } 1411 1412 static void 1413 vcheckspace(void) 1414 { 1415 1416 if (vspace() < vlowat && vnlruproc_sig == 0) { 1417 vnlruproc_sig = 1; 1418 wakeup(vnlruproc); 1419 } 1420 } 1421 1422 /* 1423 * Wait if necessary for space for a new vnode. 1424 */ 1425 static int 1426 getnewvnode_wait(int suspended) 1427 { 1428 1429 mtx_assert(&vnode_free_list_mtx, MA_OWNED); 1430 if (numvnodes >= desiredvnodes) { 1431 if (suspended) { 1432 /* 1433 * The file system is being suspended. We cannot 1434 * risk a deadlock here, so allow allocation of 1435 * another vnode even if this would give too many. 1436 */ 1437 return (0); 1438 } 1439 if (vnlruproc_sig == 0) { 1440 vnlruproc_sig = 1; /* avoid unnecessary wakeups */ 1441 wakeup(vnlruproc); 1442 } 1443 msleep(&vnlruproc_sig, &vnode_free_list_mtx, PVFS, 1444 "vlruwk", hz); 1445 } 1446 /* Post-adjust like the pre-adjust in getnewvnode(). */ 1447 if (numvnodes + 1 > desiredvnodes && freevnodes > 1) 1448 vnlru_free_locked(1, NULL); 1449 return (numvnodes >= desiredvnodes ? ENFILE : 0); 1450 } 1451 1452 /* 1453 * This hack is fragile, and probably not needed any more now that the 1454 * watermark handling works. 1455 */ 1456 void 1457 getnewvnode_reserve(u_int count) 1458 { 1459 struct thread *td; 1460 1461 /* Pre-adjust like the pre-adjust in getnewvnode(), with any count. */ 1462 /* XXX no longer so quick, but this part is not racy. */ 1463 mtx_lock(&vnode_free_list_mtx); 1464 if (numvnodes + count > desiredvnodes && freevnodes > wantfreevnodes) 1465 vnlru_free_locked(ulmin(numvnodes + count - desiredvnodes, 1466 freevnodes - wantfreevnodes), NULL); 1467 mtx_unlock(&vnode_free_list_mtx); 1468 1469 td = curthread; 1470 /* First try to be quick and racy. */ 1471 if (atomic_fetchadd_long(&numvnodes, count) + count <= desiredvnodes) { 1472 td->td_vp_reserv += count; 1473 vcheckspace(); /* XXX no longer so quick, but more racy */ 1474 return; 1475 } else 1476 atomic_subtract_long(&numvnodes, count); 1477 1478 mtx_lock(&vnode_free_list_mtx); 1479 while (count > 0) { 1480 if (getnewvnode_wait(0) == 0) { 1481 count--; 1482 td->td_vp_reserv++; 1483 atomic_add_long(&numvnodes, 1); 1484 } 1485 } 1486 vcheckspace(); 1487 mtx_unlock(&vnode_free_list_mtx); 1488 } 1489 1490 /* 1491 * This hack is fragile, especially if desiredvnodes or wantvnodes are 1492 * misconfgured or changed significantly. Reducing desiredvnodes below 1493 * the reserved amount should cause bizarre behaviour like reducing it 1494 * below the number of active vnodes -- the system will try to reduce 1495 * numvnodes to match, but should fail, so the subtraction below should 1496 * not overflow. 1497 */ 1498 void 1499 getnewvnode_drop_reserve(void) 1500 { 1501 struct thread *td; 1502 1503 td = curthread; 1504 atomic_subtract_long(&numvnodes, td->td_vp_reserv); 1505 td->td_vp_reserv = 0; 1506 } 1507 1508 /* 1509 * Return the next vnode from the free list. 1510 */ 1511 int 1512 getnewvnode(const char *tag, struct mount *mp, struct vop_vector *vops, 1513 struct vnode **vpp) 1514 { 1515 struct vnode *vp; 1516 struct thread *td; 1517 struct lock_object *lo; 1518 static int cyclecount; 1519 int error __unused; 1520 1521 CTR3(KTR_VFS, "%s: mp %p with tag %s", __func__, mp, tag); 1522 vp = NULL; 1523 td = curthread; 1524 if (td->td_vp_reserv > 0) { 1525 td->td_vp_reserv -= 1; 1526 goto alloc; 1527 } 1528 mtx_lock(&vnode_free_list_mtx); 1529 if (numvnodes < desiredvnodes) 1530 cyclecount = 0; 1531 else if (cyclecount++ >= freevnodes) { 1532 cyclecount = 0; 1533 vstir = 1; 1534 } 1535 /* 1536 * Grow the vnode cache if it will not be above its target max 1537 * after growing. Otherwise, if the free list is nonempty, try 1538 * to reclaim 1 item from it before growing the cache (possibly 1539 * above its target max if the reclamation failed or is delayed). 1540 * Otherwise, wait for some space. In all cases, schedule 1541 * vnlru_proc() if we are getting short of space. The watermarks 1542 * should be chosen so that we never wait or even reclaim from 1543 * the free list to below its target minimum. 1544 */ 1545 if (numvnodes + 1 <= desiredvnodes) 1546 ; 1547 else if (freevnodes > 0) 1548 vnlru_free_locked(1, NULL); 1549 else { 1550 error = getnewvnode_wait(mp != NULL && (mp->mnt_kern_flag & 1551 MNTK_SUSPEND)); 1552 #if 0 /* XXX Not all VFS_VGET/ffs_vget callers check returns. */ 1553 if (error != 0) { 1554 mtx_unlock(&vnode_free_list_mtx); 1555 return (error); 1556 } 1557 #endif 1558 } 1559 vcheckspace(); 1560 atomic_add_long(&numvnodes, 1); 1561 mtx_unlock(&vnode_free_list_mtx); 1562 alloc: 1563 counter_u64_add(vnodes_created, 1); 1564 vp = (struct vnode *) uma_zalloc(vnode_zone, M_WAITOK); 1565 /* 1566 * Locks are given the generic name "vnode" when created. 1567 * Follow the historic practice of using the filesystem 1568 * name when they allocated, e.g., "zfs", "ufs", "nfs, etc. 1569 * 1570 * Locks live in a witness group keyed on their name. Thus, 1571 * when a lock is renamed, it must also move from the witness 1572 * group of its old name to the witness group of its new name. 1573 * 1574 * The change only needs to be made when the vnode moves 1575 * from one filesystem type to another. We ensure that each 1576 * filesystem use a single static name pointer for its tag so 1577 * that we can compare pointers rather than doing a strcmp(). 1578 */ 1579 lo = &vp->v_vnlock->lock_object; 1580 if (lo->lo_name != tag) { 1581 lo->lo_name = tag; 1582 WITNESS_DESTROY(lo); 1583 WITNESS_INIT(lo, tag); 1584 } 1585 /* 1586 * By default, don't allow shared locks unless filesystems opt-in. 1587 */ 1588 vp->v_vnlock->lock_object.lo_flags |= LK_NOSHARE; 1589 /* 1590 * Finalize various vnode identity bits. 1591 */ 1592 KASSERT(vp->v_object == NULL, ("stale v_object %p", vp)); 1593 KASSERT(vp->v_lockf == NULL, ("stale v_lockf %p", vp)); 1594 KASSERT(vp->v_pollinfo == NULL, ("stale v_pollinfo %p", vp)); 1595 vp->v_type = VNON; 1596 vp->v_tag = tag; 1597 vp->v_op = vops; 1598 v_init_counters(vp); 1599 vp->v_bufobj.bo_ops = &buf_ops_bio; 1600 #ifdef DIAGNOSTIC 1601 if (mp == NULL && vops != &dead_vnodeops) 1602 printf("NULL mp in getnewvnode(9), tag %s\n", tag); 1603 #endif 1604 #ifdef MAC 1605 mac_vnode_init(vp); 1606 if (mp != NULL && (mp->mnt_flag & MNT_MULTILABEL) == 0) 1607 mac_vnode_associate_singlelabel(mp, vp); 1608 #endif 1609 if (mp != NULL) { 1610 vp->v_bufobj.bo_bsize = mp->mnt_stat.f_iosize; 1611 if ((mp->mnt_kern_flag & MNTK_NOKNOTE) != 0) 1612 vp->v_vflag |= VV_NOKNOTE; 1613 } 1614 1615 /* 1616 * For the filesystems which do not use vfs_hash_insert(), 1617 * still initialize v_hash to have vfs_hash_index() useful. 1618 * E.g., nullfs uses vfs_hash_index() on the lower vnode for 1619 * its own hashing. 1620 */ 1621 vp->v_hash = (uintptr_t)vp >> vnsz2log; 1622 1623 *vpp = vp; 1624 return (0); 1625 } 1626 1627 /* 1628 * Delete from old mount point vnode list, if on one. 1629 */ 1630 static void 1631 delmntque(struct vnode *vp) 1632 { 1633 struct mount *mp; 1634 int active; 1635 1636 mp = vp->v_mount; 1637 if (mp == NULL) 1638 return; 1639 MNT_ILOCK(mp); 1640 VI_LOCK(vp); 1641 KASSERT(mp->mnt_activevnodelistsize <= mp->mnt_nvnodelistsize, 1642 ("Active vnode list size %d > Vnode list size %d", 1643 mp->mnt_activevnodelistsize, mp->mnt_nvnodelistsize)); 1644 active = vp->v_iflag & VI_ACTIVE; 1645 vp->v_iflag &= ~VI_ACTIVE; 1646 if (active) { 1647 mtx_lock(&mp->mnt_listmtx); 1648 TAILQ_REMOVE(&mp->mnt_activevnodelist, vp, v_actfreelist); 1649 mp->mnt_activevnodelistsize--; 1650 mtx_unlock(&mp->mnt_listmtx); 1651 } 1652 vp->v_mount = NULL; 1653 VI_UNLOCK(vp); 1654 VNASSERT(mp->mnt_nvnodelistsize > 0, vp, 1655 ("bad mount point vnode list size")); 1656 TAILQ_REMOVE(&mp->mnt_nvnodelist, vp, v_nmntvnodes); 1657 mp->mnt_nvnodelistsize--; 1658 MNT_REL(mp); 1659 MNT_IUNLOCK(mp); 1660 } 1661 1662 static void 1663 insmntque_stddtr(struct vnode *vp, void *dtr_arg) 1664 { 1665 1666 vp->v_data = NULL; 1667 vp->v_op = &dead_vnodeops; 1668 vgone(vp); 1669 vput(vp); 1670 } 1671 1672 /* 1673 * Insert into list of vnodes for the new mount point, if available. 1674 */ 1675 int 1676 insmntque1(struct vnode *vp, struct mount *mp, 1677 void (*dtr)(struct vnode *, void *), void *dtr_arg) 1678 { 1679 1680 KASSERT(vp->v_mount == NULL, 1681 ("insmntque: vnode already on per mount vnode list")); 1682 VNASSERT(mp != NULL, vp, ("Don't call insmntque(foo, NULL)")); 1683 ASSERT_VOP_ELOCKED(vp, "insmntque: non-locked vp"); 1684 1685 /* 1686 * We acquire the vnode interlock early to ensure that the 1687 * vnode cannot be recycled by another process releasing a 1688 * holdcnt on it before we get it on both the vnode list 1689 * and the active vnode list. The mount mutex protects only 1690 * manipulation of the vnode list and the vnode freelist 1691 * mutex protects only manipulation of the active vnode list. 1692 * Hence the need to hold the vnode interlock throughout. 1693 */ 1694 MNT_ILOCK(mp); 1695 VI_LOCK(vp); 1696 if (((mp->mnt_kern_flag & MNTK_UNMOUNT) != 0 && 1697 ((mp->mnt_kern_flag & MNTK_UNMOUNTF) != 0 || 1698 mp->mnt_nvnodelistsize == 0)) && 1699 (vp->v_vflag & VV_FORCEINSMQ) == 0) { 1700 VI_UNLOCK(vp); 1701 MNT_IUNLOCK(mp); 1702 if (dtr != NULL) 1703 dtr(vp, dtr_arg); 1704 return (EBUSY); 1705 } 1706 vp->v_mount = mp; 1707 MNT_REF(mp); 1708 TAILQ_INSERT_TAIL(&mp->mnt_nvnodelist, vp, v_nmntvnodes); 1709 VNASSERT(mp->mnt_nvnodelistsize >= 0, vp, 1710 ("neg mount point vnode list size")); 1711 mp->mnt_nvnodelistsize++; 1712 KASSERT((vp->v_iflag & VI_ACTIVE) == 0, 1713 ("Activating already active vnode")); 1714 vp->v_iflag |= VI_ACTIVE; 1715 mtx_lock(&mp->mnt_listmtx); 1716 TAILQ_INSERT_HEAD(&mp->mnt_activevnodelist, vp, v_actfreelist); 1717 mp->mnt_activevnodelistsize++; 1718 mtx_unlock(&mp->mnt_listmtx); 1719 VI_UNLOCK(vp); 1720 MNT_IUNLOCK(mp); 1721 return (0); 1722 } 1723 1724 int 1725 insmntque(struct vnode *vp, struct mount *mp) 1726 { 1727 1728 return (insmntque1(vp, mp, insmntque_stddtr, NULL)); 1729 } 1730 1731 /* 1732 * Flush out and invalidate all buffers associated with a bufobj 1733 * Called with the underlying object locked. 1734 */ 1735 int 1736 bufobj_invalbuf(struct bufobj *bo, int flags, int slpflag, int slptimeo) 1737 { 1738 int error; 1739 1740 BO_LOCK(bo); 1741 if (flags & V_SAVE) { 1742 error = bufobj_wwait(bo, slpflag, slptimeo); 1743 if (error) { 1744 BO_UNLOCK(bo); 1745 return (error); 1746 } 1747 if (bo->bo_dirty.bv_cnt > 0) { 1748 BO_UNLOCK(bo); 1749 if ((error = BO_SYNC(bo, MNT_WAIT)) != 0) 1750 return (error); 1751 /* 1752 * XXX We could save a lock/unlock if this was only 1753 * enabled under INVARIANTS 1754 */ 1755 BO_LOCK(bo); 1756 if (bo->bo_numoutput > 0 || bo->bo_dirty.bv_cnt > 0) 1757 panic("vinvalbuf: dirty bufs"); 1758 } 1759 } 1760 /* 1761 * If you alter this loop please notice that interlock is dropped and 1762 * reacquired in flushbuflist. Special care is needed to ensure that 1763 * no race conditions occur from this. 1764 */ 1765 do { 1766 error = flushbuflist(&bo->bo_clean, 1767 flags, bo, slpflag, slptimeo); 1768 if (error == 0 && !(flags & V_CLEANONLY)) 1769 error = flushbuflist(&bo->bo_dirty, 1770 flags, bo, slpflag, slptimeo); 1771 if (error != 0 && error != EAGAIN) { 1772 BO_UNLOCK(bo); 1773 return (error); 1774 } 1775 } while (error != 0); 1776 1777 /* 1778 * Wait for I/O to complete. XXX needs cleaning up. The vnode can 1779 * have write I/O in-progress but if there is a VM object then the 1780 * VM object can also have read-I/O in-progress. 1781 */ 1782 do { 1783 bufobj_wwait(bo, 0, 0); 1784 if ((flags & V_VMIO) == 0 && bo->bo_object != NULL) { 1785 BO_UNLOCK(bo); 1786 vm_object_pip_wait_unlocked(bo->bo_object, "bovlbx"); 1787 BO_LOCK(bo); 1788 } 1789 } while (bo->bo_numoutput > 0); 1790 BO_UNLOCK(bo); 1791 1792 /* 1793 * Destroy the copy in the VM cache, too. 1794 */ 1795 if (bo->bo_object != NULL && 1796 (flags & (V_ALT | V_NORMAL | V_CLEANONLY | V_VMIO)) == 0) { 1797 VM_OBJECT_WLOCK(bo->bo_object); 1798 vm_object_page_remove(bo->bo_object, 0, 0, (flags & V_SAVE) ? 1799 OBJPR_CLEANONLY : 0); 1800 VM_OBJECT_WUNLOCK(bo->bo_object); 1801 } 1802 1803 #ifdef INVARIANTS 1804 BO_LOCK(bo); 1805 if ((flags & (V_ALT | V_NORMAL | V_CLEANONLY | V_VMIO | 1806 V_ALLOWCLEAN)) == 0 && (bo->bo_dirty.bv_cnt > 0 || 1807 bo->bo_clean.bv_cnt > 0)) 1808 panic("vinvalbuf: flush failed"); 1809 if ((flags & (V_ALT | V_NORMAL | V_CLEANONLY | V_VMIO)) == 0 && 1810 bo->bo_dirty.bv_cnt > 0) 1811 panic("vinvalbuf: flush dirty failed"); 1812 BO_UNLOCK(bo); 1813 #endif 1814 return (0); 1815 } 1816 1817 /* 1818 * Flush out and invalidate all buffers associated with a vnode. 1819 * Called with the underlying object locked. 1820 */ 1821 int 1822 vinvalbuf(struct vnode *vp, int flags, int slpflag, int slptimeo) 1823 { 1824 1825 CTR3(KTR_VFS, "%s: vp %p with flags %d", __func__, vp, flags); 1826 ASSERT_VOP_LOCKED(vp, "vinvalbuf"); 1827 if (vp->v_object != NULL && vp->v_object->handle != vp) 1828 return (0); 1829 return (bufobj_invalbuf(&vp->v_bufobj, flags, slpflag, slptimeo)); 1830 } 1831 1832 /* 1833 * Flush out buffers on the specified list. 1834 * 1835 */ 1836 static int 1837 flushbuflist(struct bufv *bufv, int flags, struct bufobj *bo, int slpflag, 1838 int slptimeo) 1839 { 1840 struct buf *bp, *nbp; 1841 int retval, error; 1842 daddr_t lblkno; 1843 b_xflags_t xflags; 1844 1845 ASSERT_BO_WLOCKED(bo); 1846 1847 retval = 0; 1848 TAILQ_FOREACH_SAFE(bp, &bufv->bv_hd, b_bobufs, nbp) { 1849 /* 1850 * If we are flushing both V_NORMAL and V_ALT buffers then 1851 * do not skip any buffers. If we are flushing only V_NORMAL 1852 * buffers then skip buffers marked as BX_ALTDATA. If we are 1853 * flushing only V_ALT buffers then skip buffers not marked 1854 * as BX_ALTDATA. 1855 */ 1856 if (((flags & (V_NORMAL | V_ALT)) != (V_NORMAL | V_ALT)) && 1857 (((flags & V_NORMAL) && (bp->b_xflags & BX_ALTDATA) != 0) || 1858 ((flags & V_ALT) && (bp->b_xflags & BX_ALTDATA) == 0))) { 1859 continue; 1860 } 1861 if (nbp != NULL) { 1862 lblkno = nbp->b_lblkno; 1863 xflags = nbp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN); 1864 } 1865 retval = EAGAIN; 1866 error = BUF_TIMELOCK(bp, 1867 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, BO_LOCKPTR(bo), 1868 "flushbuf", slpflag, slptimeo); 1869 if (error) { 1870 BO_LOCK(bo); 1871 return (error != ENOLCK ? error : EAGAIN); 1872 } 1873 KASSERT(bp->b_bufobj == bo, 1874 ("bp %p wrong b_bufobj %p should be %p", 1875 bp, bp->b_bufobj, bo)); 1876 /* 1877 * XXX Since there are no node locks for NFS, I 1878 * believe there is a slight chance that a delayed 1879 * write will occur while sleeping just above, so 1880 * check for it. 1881 */ 1882 if (((bp->b_flags & (B_DELWRI | B_INVAL)) == B_DELWRI) && 1883 (flags & V_SAVE)) { 1884 bremfree(bp); 1885 bp->b_flags |= B_ASYNC; 1886 bwrite(bp); 1887 BO_LOCK(bo); 1888 return (EAGAIN); /* XXX: why not loop ? */ 1889 } 1890 bremfree(bp); 1891 bp->b_flags |= (B_INVAL | B_RELBUF); 1892 bp->b_flags &= ~B_ASYNC; 1893 brelse(bp); 1894 BO_LOCK(bo); 1895 if (nbp == NULL) 1896 break; 1897 nbp = gbincore(bo, lblkno); 1898 if (nbp == NULL || (nbp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN)) 1899 != xflags) 1900 break; /* nbp invalid */ 1901 } 1902 return (retval); 1903 } 1904 1905 int 1906 bnoreuselist(struct bufv *bufv, struct bufobj *bo, daddr_t startn, daddr_t endn) 1907 { 1908 struct buf *bp; 1909 int error; 1910 daddr_t lblkno; 1911 1912 ASSERT_BO_LOCKED(bo); 1913 1914 for (lblkno = startn;;) { 1915 again: 1916 bp = BUF_PCTRIE_LOOKUP_GE(&bufv->bv_root, lblkno); 1917 if (bp == NULL || bp->b_lblkno >= endn || 1918 bp->b_lblkno < startn) 1919 break; 1920 error = BUF_TIMELOCK(bp, LK_EXCLUSIVE | LK_SLEEPFAIL | 1921 LK_INTERLOCK, BO_LOCKPTR(bo), "brlsfl", 0, 0); 1922 if (error != 0) { 1923 BO_RLOCK(bo); 1924 if (error == ENOLCK) 1925 goto again; 1926 return (error); 1927 } 1928 KASSERT(bp->b_bufobj == bo, 1929 ("bp %p wrong b_bufobj %p should be %p", 1930 bp, bp->b_bufobj, bo)); 1931 lblkno = bp->b_lblkno + 1; 1932 if ((bp->b_flags & B_MANAGED) == 0) 1933 bremfree(bp); 1934 bp->b_flags |= B_RELBUF; 1935 /* 1936 * In the VMIO case, use the B_NOREUSE flag to hint that the 1937 * pages backing each buffer in the range are unlikely to be 1938 * reused. Dirty buffers will have the hint applied once 1939 * they've been written. 1940 */ 1941 if ((bp->b_flags & B_VMIO) != 0) 1942 bp->b_flags |= B_NOREUSE; 1943 brelse(bp); 1944 BO_RLOCK(bo); 1945 } 1946 return (0); 1947 } 1948 1949 /* 1950 * Truncate a file's buffer and pages to a specified length. This 1951 * is in lieu of the old vinvalbuf mechanism, which performed unneeded 1952 * sync activity. 1953 */ 1954 int 1955 vtruncbuf(struct vnode *vp, off_t length, int blksize) 1956 { 1957 struct buf *bp, *nbp; 1958 struct bufobj *bo; 1959 daddr_t startlbn; 1960 1961 CTR4(KTR_VFS, "%s: vp %p with block %d:%ju", __func__, 1962 vp, blksize, (uintmax_t)length); 1963 1964 /* 1965 * Round up to the *next* lbn. 1966 */ 1967 startlbn = howmany(length, blksize); 1968 1969 ASSERT_VOP_LOCKED(vp, "vtruncbuf"); 1970 1971 bo = &vp->v_bufobj; 1972 restart_unlocked: 1973 BO_LOCK(bo); 1974 1975 while (v_inval_buf_range_locked(vp, bo, startlbn, INT64_MAX) == EAGAIN) 1976 ; 1977 1978 if (length > 0) { 1979 restartsync: 1980 TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) { 1981 if (bp->b_lblkno > 0) 1982 continue; 1983 /* 1984 * Since we hold the vnode lock this should only 1985 * fail if we're racing with the buf daemon. 1986 */ 1987 if (BUF_LOCK(bp, 1988 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, 1989 BO_LOCKPTR(bo)) == ENOLCK) 1990 goto restart_unlocked; 1991 1992 VNASSERT((bp->b_flags & B_DELWRI), vp, 1993 ("buf(%p) on dirty queue without DELWRI", bp)); 1994 1995 bremfree(bp); 1996 bawrite(bp); 1997 BO_LOCK(bo); 1998 goto restartsync; 1999 } 2000 } 2001 2002 bufobj_wwait(bo, 0, 0); 2003 BO_UNLOCK(bo); 2004 vnode_pager_setsize(vp, length); 2005 2006 return (0); 2007 } 2008 2009 /* 2010 * Invalidate the cached pages of a file's buffer within the range of block 2011 * numbers [startlbn, endlbn). 2012 */ 2013 void 2014 v_inval_buf_range(struct vnode *vp, daddr_t startlbn, daddr_t endlbn, 2015 int blksize) 2016 { 2017 struct bufobj *bo; 2018 off_t start, end; 2019 2020 ASSERT_VOP_LOCKED(vp, "v_inval_buf_range"); 2021 2022 start = blksize * startlbn; 2023 end = blksize * endlbn; 2024 2025 bo = &vp->v_bufobj; 2026 BO_LOCK(bo); 2027 MPASS(blksize == bo->bo_bsize); 2028 2029 while (v_inval_buf_range_locked(vp, bo, startlbn, endlbn) == EAGAIN) 2030 ; 2031 2032 BO_UNLOCK(bo); 2033 vn_pages_remove(vp, OFF_TO_IDX(start), OFF_TO_IDX(end + PAGE_SIZE - 1)); 2034 } 2035 2036 static int 2037 v_inval_buf_range_locked(struct vnode *vp, struct bufobj *bo, 2038 daddr_t startlbn, daddr_t endlbn) 2039 { 2040 struct buf *bp, *nbp; 2041 bool anyfreed; 2042 2043 ASSERT_VOP_LOCKED(vp, "v_inval_buf_range_locked"); 2044 ASSERT_BO_LOCKED(bo); 2045 2046 do { 2047 anyfreed = false; 2048 TAILQ_FOREACH_SAFE(bp, &bo->bo_clean.bv_hd, b_bobufs, nbp) { 2049 if (bp->b_lblkno < startlbn || bp->b_lblkno >= endlbn) 2050 continue; 2051 if (BUF_LOCK(bp, 2052 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, 2053 BO_LOCKPTR(bo)) == ENOLCK) { 2054 BO_LOCK(bo); 2055 return (EAGAIN); 2056 } 2057 2058 bremfree(bp); 2059 bp->b_flags |= B_INVAL | B_RELBUF; 2060 bp->b_flags &= ~B_ASYNC; 2061 brelse(bp); 2062 anyfreed = true; 2063 2064 BO_LOCK(bo); 2065 if (nbp != NULL && 2066 (((nbp->b_xflags & BX_VNCLEAN) == 0) || 2067 nbp->b_vp != vp || 2068 (nbp->b_flags & B_DELWRI) != 0)) 2069 return (EAGAIN); 2070 } 2071 2072 TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) { 2073 if (bp->b_lblkno < startlbn || bp->b_lblkno >= endlbn) 2074 continue; 2075 if (BUF_LOCK(bp, 2076 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, 2077 BO_LOCKPTR(bo)) == ENOLCK) { 2078 BO_LOCK(bo); 2079 return (EAGAIN); 2080 } 2081 bremfree(bp); 2082 bp->b_flags |= B_INVAL | B_RELBUF; 2083 bp->b_flags &= ~B_ASYNC; 2084 brelse(bp); 2085 anyfreed = true; 2086 2087 BO_LOCK(bo); 2088 if (nbp != NULL && 2089 (((nbp->b_xflags & BX_VNDIRTY) == 0) || 2090 (nbp->b_vp != vp) || 2091 (nbp->b_flags & B_DELWRI) == 0)) 2092 return (EAGAIN); 2093 } 2094 } while (anyfreed); 2095 return (0); 2096 } 2097 2098 static void 2099 buf_vlist_remove(struct buf *bp) 2100 { 2101 struct bufv *bv; 2102 2103 KASSERT(bp->b_bufobj != NULL, ("No b_bufobj %p", bp)); 2104 ASSERT_BO_WLOCKED(bp->b_bufobj); 2105 KASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) != 2106 (BX_VNDIRTY|BX_VNCLEAN), 2107 ("buf_vlist_remove: Buf %p is on two lists", bp)); 2108 if (bp->b_xflags & BX_VNDIRTY) 2109 bv = &bp->b_bufobj->bo_dirty; 2110 else 2111 bv = &bp->b_bufobj->bo_clean; 2112 BUF_PCTRIE_REMOVE(&bv->bv_root, bp->b_lblkno); 2113 TAILQ_REMOVE(&bv->bv_hd, bp, b_bobufs); 2114 bv->bv_cnt--; 2115 bp->b_xflags &= ~(BX_VNDIRTY | BX_VNCLEAN); 2116 } 2117 2118 /* 2119 * Add the buffer to the sorted clean or dirty block list. 2120 * 2121 * NOTE: xflags is passed as a constant, optimizing this inline function! 2122 */ 2123 static void 2124 buf_vlist_add(struct buf *bp, struct bufobj *bo, b_xflags_t xflags) 2125 { 2126 struct bufv *bv; 2127 struct buf *n; 2128 int error; 2129 2130 ASSERT_BO_WLOCKED(bo); 2131 KASSERT((xflags & BX_VNDIRTY) == 0 || (bo->bo_flag & BO_DEAD) == 0, 2132 ("dead bo %p", bo)); 2133 KASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) == 0, 2134 ("buf_vlist_add: Buf %p has existing xflags %d", bp, bp->b_xflags)); 2135 bp->b_xflags |= xflags; 2136 if (xflags & BX_VNDIRTY) 2137 bv = &bo->bo_dirty; 2138 else 2139 bv = &bo->bo_clean; 2140 2141 /* 2142 * Keep the list ordered. Optimize empty list insertion. Assume 2143 * we tend to grow at the tail so lookup_le should usually be cheaper 2144 * than _ge. 2145 */ 2146 if (bv->bv_cnt == 0 || 2147 bp->b_lblkno > TAILQ_LAST(&bv->bv_hd, buflists)->b_lblkno) 2148 TAILQ_INSERT_TAIL(&bv->bv_hd, bp, b_bobufs); 2149 else if ((n = BUF_PCTRIE_LOOKUP_LE(&bv->bv_root, bp->b_lblkno)) == NULL) 2150 TAILQ_INSERT_HEAD(&bv->bv_hd, bp, b_bobufs); 2151 else 2152 TAILQ_INSERT_AFTER(&bv->bv_hd, n, bp, b_bobufs); 2153 error = BUF_PCTRIE_INSERT(&bv->bv_root, bp); 2154 if (error) 2155 panic("buf_vlist_add: Preallocated nodes insufficient."); 2156 bv->bv_cnt++; 2157 } 2158 2159 /* 2160 * Look up a buffer using the buffer tries. 2161 */ 2162 struct buf * 2163 gbincore(struct bufobj *bo, daddr_t lblkno) 2164 { 2165 struct buf *bp; 2166 2167 ASSERT_BO_LOCKED(bo); 2168 bp = BUF_PCTRIE_LOOKUP(&bo->bo_clean.bv_root, lblkno); 2169 if (bp != NULL) 2170 return (bp); 2171 return BUF_PCTRIE_LOOKUP(&bo->bo_dirty.bv_root, lblkno); 2172 } 2173 2174 /* 2175 * Associate a buffer with a vnode. 2176 */ 2177 void 2178 bgetvp(struct vnode *vp, struct buf *bp) 2179 { 2180 struct bufobj *bo; 2181 2182 bo = &vp->v_bufobj; 2183 ASSERT_BO_WLOCKED(bo); 2184 VNASSERT(bp->b_vp == NULL, bp->b_vp, ("bgetvp: not free")); 2185 2186 CTR3(KTR_BUF, "bgetvp(%p) vp %p flags %X", bp, vp, bp->b_flags); 2187 VNASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) == 0, vp, 2188 ("bgetvp: bp already attached! %p", bp)); 2189 2190 vhold(vp); 2191 bp->b_vp = vp; 2192 bp->b_bufobj = bo; 2193 /* 2194 * Insert onto list for new vnode. 2195 */ 2196 buf_vlist_add(bp, bo, BX_VNCLEAN); 2197 } 2198 2199 /* 2200 * Disassociate a buffer from a vnode. 2201 */ 2202 void 2203 brelvp(struct buf *bp) 2204 { 2205 struct bufobj *bo; 2206 struct vnode *vp; 2207 2208 CTR3(KTR_BUF, "brelvp(%p) vp %p flags %X", bp, bp->b_vp, bp->b_flags); 2209 KASSERT(bp->b_vp != NULL, ("brelvp: NULL")); 2210 2211 /* 2212 * Delete from old vnode list, if on one. 2213 */ 2214 vp = bp->b_vp; /* XXX */ 2215 bo = bp->b_bufobj; 2216 BO_LOCK(bo); 2217 if (bp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN)) 2218 buf_vlist_remove(bp); 2219 else 2220 panic("brelvp: Buffer %p not on queue.", bp); 2221 if ((bo->bo_flag & BO_ONWORKLST) && bo->bo_dirty.bv_cnt == 0) { 2222 bo->bo_flag &= ~BO_ONWORKLST; 2223 mtx_lock(&sync_mtx); 2224 LIST_REMOVE(bo, bo_synclist); 2225 syncer_worklist_len--; 2226 mtx_unlock(&sync_mtx); 2227 } 2228 bp->b_vp = NULL; 2229 bp->b_bufobj = NULL; 2230 BO_UNLOCK(bo); 2231 vdrop(vp); 2232 } 2233 2234 /* 2235 * Add an item to the syncer work queue. 2236 */ 2237 static void 2238 vn_syncer_add_to_worklist(struct bufobj *bo, int delay) 2239 { 2240 int slot; 2241 2242 ASSERT_BO_WLOCKED(bo); 2243 2244 mtx_lock(&sync_mtx); 2245 if (bo->bo_flag & BO_ONWORKLST) 2246 LIST_REMOVE(bo, bo_synclist); 2247 else { 2248 bo->bo_flag |= BO_ONWORKLST; 2249 syncer_worklist_len++; 2250 } 2251 2252 if (delay > syncer_maxdelay - 2) 2253 delay = syncer_maxdelay - 2; 2254 slot = (syncer_delayno + delay) & syncer_mask; 2255 2256 LIST_INSERT_HEAD(&syncer_workitem_pending[slot], bo, bo_synclist); 2257 mtx_unlock(&sync_mtx); 2258 } 2259 2260 static int 2261 sysctl_vfs_worklist_len(SYSCTL_HANDLER_ARGS) 2262 { 2263 int error, len; 2264 2265 mtx_lock(&sync_mtx); 2266 len = syncer_worklist_len - sync_vnode_count; 2267 mtx_unlock(&sync_mtx); 2268 error = SYSCTL_OUT(req, &len, sizeof(len)); 2269 return (error); 2270 } 2271 2272 SYSCTL_PROC(_vfs, OID_AUTO, worklist_len, CTLTYPE_INT | CTLFLAG_RD, NULL, 0, 2273 sysctl_vfs_worklist_len, "I", "Syncer thread worklist length"); 2274 2275 static struct proc *updateproc; 2276 static void sched_sync(void); 2277 static struct kproc_desc up_kp = { 2278 "syncer", 2279 sched_sync, 2280 &updateproc 2281 }; 2282 SYSINIT(syncer, SI_SUB_KTHREAD_UPDATE, SI_ORDER_FIRST, kproc_start, &up_kp); 2283 2284 static int 2285 sync_vnode(struct synclist *slp, struct bufobj **bo, struct thread *td) 2286 { 2287 struct vnode *vp; 2288 struct mount *mp; 2289 2290 *bo = LIST_FIRST(slp); 2291 if (*bo == NULL) 2292 return (0); 2293 vp = bo2vnode(*bo); 2294 if (VOP_ISLOCKED(vp) != 0 || VI_TRYLOCK(vp) == 0) 2295 return (1); 2296 /* 2297 * We use vhold in case the vnode does not 2298 * successfully sync. vhold prevents the vnode from 2299 * going away when we unlock the sync_mtx so that 2300 * we can acquire the vnode interlock. 2301 */ 2302 vholdl(vp); 2303 mtx_unlock(&sync_mtx); 2304 VI_UNLOCK(vp); 2305 if (vn_start_write(vp, &mp, V_NOWAIT) != 0) { 2306 vdrop(vp); 2307 mtx_lock(&sync_mtx); 2308 return (*bo == LIST_FIRST(slp)); 2309 } 2310 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 2311 (void) VOP_FSYNC(vp, MNT_LAZY, td); 2312 VOP_UNLOCK(vp, 0); 2313 vn_finished_write(mp); 2314 BO_LOCK(*bo); 2315 if (((*bo)->bo_flag & BO_ONWORKLST) != 0) { 2316 /* 2317 * Put us back on the worklist. The worklist 2318 * routine will remove us from our current 2319 * position and then add us back in at a later 2320 * position. 2321 */ 2322 vn_syncer_add_to_worklist(*bo, syncdelay); 2323 } 2324 BO_UNLOCK(*bo); 2325 vdrop(vp); 2326 mtx_lock(&sync_mtx); 2327 return (0); 2328 } 2329 2330 static int first_printf = 1; 2331 2332 /* 2333 * System filesystem synchronizer daemon. 2334 */ 2335 static void 2336 sched_sync(void) 2337 { 2338 struct synclist *next, *slp; 2339 struct bufobj *bo; 2340 long starttime; 2341 struct thread *td = curthread; 2342 int last_work_seen; 2343 int net_worklist_len; 2344 int syncer_final_iter; 2345 int error; 2346 2347 last_work_seen = 0; 2348 syncer_final_iter = 0; 2349 syncer_state = SYNCER_RUNNING; 2350 starttime = time_uptime; 2351 td->td_pflags |= TDP_NORUNNINGBUF; 2352 2353 EVENTHANDLER_REGISTER(shutdown_pre_sync, syncer_shutdown, td->td_proc, 2354 SHUTDOWN_PRI_LAST); 2355 2356 mtx_lock(&sync_mtx); 2357 for (;;) { 2358 if (syncer_state == SYNCER_FINAL_DELAY && 2359 syncer_final_iter == 0) { 2360 mtx_unlock(&sync_mtx); 2361 kproc_suspend_check(td->td_proc); 2362 mtx_lock(&sync_mtx); 2363 } 2364 net_worklist_len = syncer_worklist_len - sync_vnode_count; 2365 if (syncer_state != SYNCER_RUNNING && 2366 starttime != time_uptime) { 2367 if (first_printf) { 2368 printf("\nSyncing disks, vnodes remaining... "); 2369 first_printf = 0; 2370 } 2371 printf("%d ", net_worklist_len); 2372 } 2373 starttime = time_uptime; 2374 2375 /* 2376 * Push files whose dirty time has expired. Be careful 2377 * of interrupt race on slp queue. 2378 * 2379 * Skip over empty worklist slots when shutting down. 2380 */ 2381 do { 2382 slp = &syncer_workitem_pending[syncer_delayno]; 2383 syncer_delayno += 1; 2384 if (syncer_delayno == syncer_maxdelay) 2385 syncer_delayno = 0; 2386 next = &syncer_workitem_pending[syncer_delayno]; 2387 /* 2388 * If the worklist has wrapped since the 2389 * it was emptied of all but syncer vnodes, 2390 * switch to the FINAL_DELAY state and run 2391 * for one more second. 2392 */ 2393 if (syncer_state == SYNCER_SHUTTING_DOWN && 2394 net_worklist_len == 0 && 2395 last_work_seen == syncer_delayno) { 2396 syncer_state = SYNCER_FINAL_DELAY; 2397 syncer_final_iter = SYNCER_SHUTDOWN_SPEEDUP; 2398 } 2399 } while (syncer_state != SYNCER_RUNNING && LIST_EMPTY(slp) && 2400 syncer_worklist_len > 0); 2401 2402 /* 2403 * Keep track of the last time there was anything 2404 * on the worklist other than syncer vnodes. 2405 * Return to the SHUTTING_DOWN state if any 2406 * new work appears. 2407 */ 2408 if (net_worklist_len > 0 || syncer_state == SYNCER_RUNNING) 2409 last_work_seen = syncer_delayno; 2410 if (net_worklist_len > 0 && syncer_state == SYNCER_FINAL_DELAY) 2411 syncer_state = SYNCER_SHUTTING_DOWN; 2412 while (!LIST_EMPTY(slp)) { 2413 error = sync_vnode(slp, &bo, td); 2414 if (error == 1) { 2415 LIST_REMOVE(bo, bo_synclist); 2416 LIST_INSERT_HEAD(next, bo, bo_synclist); 2417 continue; 2418 } 2419 2420 if (first_printf == 0) { 2421 /* 2422 * Drop the sync mutex, because some watchdog 2423 * drivers need to sleep while patting 2424 */ 2425 mtx_unlock(&sync_mtx); 2426 wdog_kern_pat(WD_LASTVAL); 2427 mtx_lock(&sync_mtx); 2428 } 2429 2430 } 2431 if (syncer_state == SYNCER_FINAL_DELAY && syncer_final_iter > 0) 2432 syncer_final_iter--; 2433 /* 2434 * The variable rushjob allows the kernel to speed up the 2435 * processing of the filesystem syncer process. A rushjob 2436 * value of N tells the filesystem syncer to process the next 2437 * N seconds worth of work on its queue ASAP. Currently rushjob 2438 * is used by the soft update code to speed up the filesystem 2439 * syncer process when the incore state is getting so far 2440 * ahead of the disk that the kernel memory pool is being 2441 * threatened with exhaustion. 2442 */ 2443 if (rushjob > 0) { 2444 rushjob -= 1; 2445 continue; 2446 } 2447 /* 2448 * Just sleep for a short period of time between 2449 * iterations when shutting down to allow some I/O 2450 * to happen. 2451 * 2452 * If it has taken us less than a second to process the 2453 * current work, then wait. Otherwise start right over 2454 * again. We can still lose time if any single round 2455 * takes more than two seconds, but it does not really 2456 * matter as we are just trying to generally pace the 2457 * filesystem activity. 2458 */ 2459 if (syncer_state != SYNCER_RUNNING || 2460 time_uptime == starttime) { 2461 thread_lock(td); 2462 sched_prio(td, PPAUSE); 2463 thread_unlock(td); 2464 } 2465 if (syncer_state != SYNCER_RUNNING) 2466 cv_timedwait(&sync_wakeup, &sync_mtx, 2467 hz / SYNCER_SHUTDOWN_SPEEDUP); 2468 else if (time_uptime == starttime) 2469 cv_timedwait(&sync_wakeup, &sync_mtx, hz); 2470 } 2471 } 2472 2473 /* 2474 * Request the syncer daemon to speed up its work. 2475 * We never push it to speed up more than half of its 2476 * normal turn time, otherwise it could take over the cpu. 2477 */ 2478 int 2479 speedup_syncer(void) 2480 { 2481 int ret = 0; 2482 2483 mtx_lock(&sync_mtx); 2484 if (rushjob < syncdelay / 2) { 2485 rushjob += 1; 2486 stat_rush_requests += 1; 2487 ret = 1; 2488 } 2489 mtx_unlock(&sync_mtx); 2490 cv_broadcast(&sync_wakeup); 2491 return (ret); 2492 } 2493 2494 /* 2495 * Tell the syncer to speed up its work and run though its work 2496 * list several times, then tell it to shut down. 2497 */ 2498 static void 2499 syncer_shutdown(void *arg, int howto) 2500 { 2501 2502 if (howto & RB_NOSYNC) 2503 return; 2504 mtx_lock(&sync_mtx); 2505 syncer_state = SYNCER_SHUTTING_DOWN; 2506 rushjob = 0; 2507 mtx_unlock(&sync_mtx); 2508 cv_broadcast(&sync_wakeup); 2509 kproc_shutdown(arg, howto); 2510 } 2511 2512 void 2513 syncer_suspend(void) 2514 { 2515 2516 syncer_shutdown(updateproc, 0); 2517 } 2518 2519 void 2520 syncer_resume(void) 2521 { 2522 2523 mtx_lock(&sync_mtx); 2524 first_printf = 1; 2525 syncer_state = SYNCER_RUNNING; 2526 mtx_unlock(&sync_mtx); 2527 cv_broadcast(&sync_wakeup); 2528 kproc_resume(updateproc); 2529 } 2530 2531 /* 2532 * Reassign a buffer from one vnode to another. 2533 * Used to assign file specific control information 2534 * (indirect blocks) to the vnode to which they belong. 2535 */ 2536 void 2537 reassignbuf(struct buf *bp) 2538 { 2539 struct vnode *vp; 2540 struct bufobj *bo; 2541 int delay; 2542 #ifdef INVARIANTS 2543 struct bufv *bv; 2544 #endif 2545 2546 vp = bp->b_vp; 2547 bo = bp->b_bufobj; 2548 ++reassignbufcalls; 2549 2550 CTR3(KTR_BUF, "reassignbuf(%p) vp %p flags %X", 2551 bp, bp->b_vp, bp->b_flags); 2552 /* 2553 * B_PAGING flagged buffers cannot be reassigned because their vp 2554 * is not fully linked in. 2555 */ 2556 if (bp->b_flags & B_PAGING) 2557 panic("cannot reassign paging buffer"); 2558 2559 /* 2560 * Delete from old vnode list, if on one. 2561 */ 2562 BO_LOCK(bo); 2563 if (bp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN)) 2564 buf_vlist_remove(bp); 2565 else 2566 panic("reassignbuf: Buffer %p not on queue.", bp); 2567 /* 2568 * If dirty, put on list of dirty buffers; otherwise insert onto list 2569 * of clean buffers. 2570 */ 2571 if (bp->b_flags & B_DELWRI) { 2572 if ((bo->bo_flag & BO_ONWORKLST) == 0) { 2573 switch (vp->v_type) { 2574 case VDIR: 2575 delay = dirdelay; 2576 break; 2577 case VCHR: 2578 delay = metadelay; 2579 break; 2580 default: 2581 delay = filedelay; 2582 } 2583 vn_syncer_add_to_worklist(bo, delay); 2584 } 2585 buf_vlist_add(bp, bo, BX_VNDIRTY); 2586 } else { 2587 buf_vlist_add(bp, bo, BX_VNCLEAN); 2588 2589 if ((bo->bo_flag & BO_ONWORKLST) && bo->bo_dirty.bv_cnt == 0) { 2590 mtx_lock(&sync_mtx); 2591 LIST_REMOVE(bo, bo_synclist); 2592 syncer_worklist_len--; 2593 mtx_unlock(&sync_mtx); 2594 bo->bo_flag &= ~BO_ONWORKLST; 2595 } 2596 } 2597 #ifdef INVARIANTS 2598 bv = &bo->bo_clean; 2599 bp = TAILQ_FIRST(&bv->bv_hd); 2600 KASSERT(bp == NULL || bp->b_bufobj == bo, 2601 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 2602 bp = TAILQ_LAST(&bv->bv_hd, buflists); 2603 KASSERT(bp == NULL || bp->b_bufobj == bo, 2604 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 2605 bv = &bo->bo_dirty; 2606 bp = TAILQ_FIRST(&bv->bv_hd); 2607 KASSERT(bp == NULL || bp->b_bufobj == bo, 2608 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 2609 bp = TAILQ_LAST(&bv->bv_hd, buflists); 2610 KASSERT(bp == NULL || bp->b_bufobj == bo, 2611 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 2612 #endif 2613 BO_UNLOCK(bo); 2614 } 2615 2616 static void 2617 v_init_counters(struct vnode *vp) 2618 { 2619 2620 VNASSERT(vp->v_type == VNON && vp->v_data == NULL && vp->v_iflag == 0, 2621 vp, ("%s called for an initialized vnode", __FUNCTION__)); 2622 ASSERT_VI_UNLOCKED(vp, __FUNCTION__); 2623 2624 refcount_init(&vp->v_holdcnt, 1); 2625 refcount_init(&vp->v_usecount, 1); 2626 } 2627 2628 /* 2629 * Increment si_usecount of the associated device, if any. 2630 */ 2631 static void 2632 v_incr_devcount(struct vnode *vp) 2633 { 2634 2635 ASSERT_VI_LOCKED(vp, __FUNCTION__); 2636 if (vp->v_type == VCHR && vp->v_rdev != NULL) { 2637 dev_lock(); 2638 vp->v_rdev->si_usecount++; 2639 dev_unlock(); 2640 } 2641 } 2642 2643 /* 2644 * Decrement si_usecount of the associated device, if any. 2645 */ 2646 static void 2647 v_decr_devcount(struct vnode *vp) 2648 { 2649 2650 ASSERT_VI_LOCKED(vp, __FUNCTION__); 2651 if (vp->v_type == VCHR && vp->v_rdev != NULL) { 2652 dev_lock(); 2653 vp->v_rdev->si_usecount--; 2654 dev_unlock(); 2655 } 2656 } 2657 2658 /* 2659 * Grab a particular vnode from the free list, increment its 2660 * reference count and lock it. VI_DOOMED is set if the vnode 2661 * is being destroyed. Only callers who specify LK_RETRY will 2662 * see doomed vnodes. If inactive processing was delayed in 2663 * vput try to do it here. 2664 * 2665 * Notes on lockless counter manipulation: 2666 * _vhold, vputx and other routines make various decisions based 2667 * on either holdcnt or usecount being 0. As long as either counter 2668 * is not transitioning 0->1 nor 1->0, the manipulation can be done 2669 * with atomic operations. Otherwise the interlock is taken covering 2670 * both the atomic and additional actions. 2671 */ 2672 static enum vgetstate 2673 _vget_prep(struct vnode *vp, bool interlock) 2674 { 2675 enum vgetstate vs; 2676 2677 if (__predict_true(vp->v_type != VCHR)) { 2678 if (refcount_acquire_if_not_zero(&vp->v_usecount)) { 2679 vs = VGET_USECOUNT; 2680 } else { 2681 _vhold(vp, interlock); 2682 vs = VGET_HOLDCNT; 2683 } 2684 } else { 2685 if (!interlock) 2686 VI_LOCK(vp); 2687 if (vp->v_usecount == 0) { 2688 vholdl(vp); 2689 vs = VGET_HOLDCNT; 2690 } else { 2691 v_incr_devcount(vp); 2692 refcount_acquire(&vp->v_usecount); 2693 vs = VGET_USECOUNT; 2694 } 2695 if (!interlock) 2696 VI_UNLOCK(vp); 2697 } 2698 return (vs); 2699 } 2700 2701 enum vgetstate 2702 vget_prep(struct vnode *vp) 2703 { 2704 2705 return (_vget_prep(vp, false)); 2706 } 2707 2708 int 2709 vget(struct vnode *vp, int flags, struct thread *td) 2710 { 2711 enum vgetstate vs; 2712 2713 MPASS(td == curthread); 2714 2715 vs = _vget_prep(vp, (flags & LK_INTERLOCK) != 0); 2716 return (vget_finish(vp, flags, vs)); 2717 } 2718 2719 int 2720 vget_finish(struct vnode *vp, int flags, enum vgetstate vs) 2721 { 2722 int error, oweinact; 2723 2724 VNASSERT((flags & LK_TYPE_MASK) != 0, vp, 2725 ("%s: invalid lock operation", __func__)); 2726 2727 if ((flags & LK_INTERLOCK) != 0) 2728 ASSERT_VI_LOCKED(vp, __func__); 2729 else 2730 ASSERT_VI_UNLOCKED(vp, __func__); 2731 VNASSERT(vp->v_holdcnt > 0, vp, ("%s: vnode not held", __func__)); 2732 if (vs == VGET_USECOUNT) { 2733 VNASSERT(vp->v_usecount > 0, vp, 2734 ("%s: vnode without usecount when VGET_USECOUNT was passed", 2735 __func__)); 2736 } 2737 2738 if ((error = vn_lock(vp, flags)) != 0) { 2739 if (vs == VGET_USECOUNT) 2740 vrele(vp); 2741 else 2742 vdrop(vp); 2743 CTR2(KTR_VFS, "%s: impossible to lock vnode %p", __func__, 2744 vp); 2745 return (error); 2746 } 2747 2748 if (vs == VGET_USECOUNT) { 2749 VNASSERT((vp->v_iflag & VI_OWEINACT) == 0, vp, 2750 ("%s: vnode with usecount and VI_OWEINACT set", __func__)); 2751 return (0); 2752 } 2753 2754 /* 2755 * We hold the vnode. If the usecount is 0 it will be utilized to keep 2756 * the vnode around. Otherwise someone else lended their hold count and 2757 * we have to drop ours. 2758 */ 2759 if (vp->v_type != VCHR && 2760 refcount_acquire_if_not_zero(&vp->v_usecount)) { 2761 #ifdef INVARIANTS 2762 int old = atomic_fetchadd_int(&vp->v_holdcnt, -1) - 1; 2763 VNASSERT(old > 0, vp, ("%s: wrong hold count", __func__)); 2764 #else 2765 refcount_release(&vp->v_holdcnt); 2766 #endif 2767 VNODE_REFCOUNT_FENCE_ACQ(); 2768 VNASSERT((vp->v_iflag & VI_OWEINACT) == 0, vp, 2769 ("%s: vnode with usecount and VI_OWEINACT set", __func__)); 2770 return (0); 2771 } 2772 2773 /* 2774 * We don't guarantee that any particular close will 2775 * trigger inactive processing so just make a best effort 2776 * here at preventing a reference to a removed file. If 2777 * we don't succeed no harm is done. 2778 * 2779 * Upgrade our holdcnt to a usecount. 2780 */ 2781 VI_LOCK(vp); 2782 if ((vp->v_iflag & VI_OWEINACT) == 0) { 2783 oweinact = 0; 2784 } else { 2785 oweinact = 1; 2786 vp->v_iflag &= ~VI_OWEINACT; 2787 VNODE_REFCOUNT_FENCE_REL(); 2788 } 2789 if (vp->v_usecount > 0) 2790 refcount_release(&vp->v_holdcnt); 2791 v_incr_devcount(vp); 2792 refcount_acquire(&vp->v_usecount); 2793 if (oweinact && VOP_ISLOCKED(vp) == LK_EXCLUSIVE && 2794 (flags & LK_NOWAIT) == 0) 2795 vinactive(vp, curthread); 2796 VI_UNLOCK(vp); 2797 return (0); 2798 } 2799 2800 /* 2801 * Increase the reference (use) and hold count of a vnode. 2802 * This will also remove the vnode from the free list if it is presently free. 2803 */ 2804 void 2805 vref(struct vnode *vp) 2806 { 2807 2808 ASSERT_VI_UNLOCKED(vp, __func__); 2809 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2810 if (vp->v_type != VCHR && 2811 refcount_acquire_if_not_zero(&vp->v_usecount)) { 2812 VNODE_REFCOUNT_FENCE_ACQ(); 2813 VNASSERT(vp->v_holdcnt > 0, vp, 2814 ("%s: active vnode not held", __func__)); 2815 VNASSERT((vp->v_iflag & VI_OWEINACT) == 0, vp, 2816 ("%s: vnode with usecount and VI_OWEINACT set", __func__)); 2817 return; 2818 } 2819 VI_LOCK(vp); 2820 vrefl(vp); 2821 VI_UNLOCK(vp); 2822 } 2823 2824 void 2825 vrefl(struct vnode *vp) 2826 { 2827 2828 ASSERT_VI_LOCKED(vp, __func__); 2829 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2830 if (vp->v_usecount == 0) 2831 vholdl(vp); 2832 if ((vp->v_iflag & VI_OWEINACT) != 0) { 2833 vp->v_iflag &= ~VI_OWEINACT; 2834 VNODE_REFCOUNT_FENCE_REL(); 2835 } 2836 v_incr_devcount(vp); 2837 refcount_acquire(&vp->v_usecount); 2838 } 2839 2840 void 2841 vrefact(struct vnode *vp) 2842 { 2843 2844 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2845 if (__predict_false(vp->v_type == VCHR)) { 2846 VNASSERT(vp->v_holdcnt > 0 && vp->v_usecount > 0, vp, 2847 ("%s: wrong ref counts", __func__)); 2848 vref(vp); 2849 return; 2850 } 2851 #ifdef INVARIANTS 2852 int old = atomic_fetchadd_int(&vp->v_usecount, 1); 2853 VNASSERT(old > 0, vp, ("%s: wrong use count", __func__)); 2854 #else 2855 refcount_acquire(&vp->v_usecount); 2856 #endif 2857 } 2858 2859 /* 2860 * Return reference count of a vnode. 2861 * 2862 * The results of this call are only guaranteed when some mechanism is used to 2863 * stop other processes from gaining references to the vnode. This may be the 2864 * case if the caller holds the only reference. This is also useful when stale 2865 * data is acceptable as race conditions may be accounted for by some other 2866 * means. 2867 */ 2868 int 2869 vrefcnt(struct vnode *vp) 2870 { 2871 2872 return (vp->v_usecount); 2873 } 2874 2875 #define VPUTX_VRELE 1 2876 #define VPUTX_VPUT 2 2877 #define VPUTX_VUNREF 3 2878 2879 /* 2880 * Decrement the use and hold counts for a vnode. 2881 * 2882 * See an explanation near vget() as to why atomic operation is safe. 2883 */ 2884 static void 2885 vputx(struct vnode *vp, int func) 2886 { 2887 int error; 2888 2889 KASSERT(vp != NULL, ("vputx: null vp")); 2890 if (func == VPUTX_VUNREF) 2891 ASSERT_VOP_LOCKED(vp, "vunref"); 2892 else if (func == VPUTX_VPUT) 2893 ASSERT_VOP_LOCKED(vp, "vput"); 2894 else 2895 KASSERT(func == VPUTX_VRELE, ("vputx: wrong func")); 2896 ASSERT_VI_UNLOCKED(vp, __func__); 2897 VNASSERT(vp->v_holdcnt > 0 && vp->v_usecount > 0, vp, 2898 ("%s: wrong ref counts", __func__)); 2899 2900 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2901 2902 /* 2903 * It is an invariant that all VOP_* calls operate on a held vnode. 2904 * We may be only having an implicit hold stemming from our usecount, 2905 * which we are about to release. If we unlock the vnode afterwards we 2906 * open a time window where someone else dropped the last usecount and 2907 * proceeded to free the vnode before our unlock finished. For this 2908 * reason we unlock the vnode early. This is a little bit wasteful as 2909 * it may be the vnode is exclusively locked and inactive processing is 2910 * needed, in which case we are adding work. 2911 */ 2912 if (func == VPUTX_VPUT) 2913 VOP_UNLOCK(vp, 0); 2914 2915 if (vp->v_type != VCHR && 2916 refcount_release_if_not_last(&vp->v_usecount)) 2917 return; 2918 2919 VI_LOCK(vp); 2920 2921 /* 2922 * We want to hold the vnode until the inactive finishes to 2923 * prevent vgone() races. We drop the use count here and the 2924 * hold count below when we're done. 2925 */ 2926 v_decr_devcount(vp); 2927 if (!refcount_release(&vp->v_usecount)) { 2928 VI_UNLOCK(vp); 2929 return; 2930 } 2931 if (vp->v_iflag & VI_DOINGINACT) { 2932 vdropl(vp); 2933 return; 2934 } 2935 2936 error = 0; 2937 2938 if (vp->v_usecount != 0) { 2939 vn_printf(vp, "vputx: usecount not zero for vnode "); 2940 panic("vputx: usecount not zero"); 2941 } 2942 2943 CTR2(KTR_VFS, "%s: return vnode %p to the freelist", __func__, vp); 2944 2945 /* 2946 * Check if the fs wants to perform inactive processing. Note we 2947 * may be only holding the interlock, in which case it is possible 2948 * someone else called vgone on the vnode and ->v_data is now NULL. 2949 * Since vgone performs inactive on its own there is nothing to do 2950 * here but to drop our hold count. 2951 */ 2952 if (__predict_false(vp->v_iflag & VI_DOOMED) || 2953 VOP_NEED_INACTIVE(vp) == 0) { 2954 vdropl(vp); 2955 return; 2956 } 2957 2958 /* 2959 * We must call VOP_INACTIVE with the node locked. Mark 2960 * as VI_DOINGINACT to avoid recursion. 2961 */ 2962 vp->v_iflag |= VI_OWEINACT; 2963 switch (func) { 2964 case VPUTX_VRELE: 2965 error = vn_lock(vp, LK_EXCLUSIVE | LK_INTERLOCK); 2966 VI_LOCK(vp); 2967 break; 2968 case VPUTX_VPUT: 2969 error = VOP_LOCK(vp, LK_EXCLUSIVE | LK_INTERLOCK | LK_NOWAIT); 2970 VI_LOCK(vp); 2971 break; 2972 case VPUTX_VUNREF: 2973 if (VOP_ISLOCKED(vp) != LK_EXCLUSIVE) { 2974 error = VOP_LOCK(vp, LK_TRYUPGRADE | LK_INTERLOCK); 2975 VI_LOCK(vp); 2976 } 2977 break; 2978 } 2979 VNASSERT(vp->v_usecount == 0 || (vp->v_iflag & VI_OWEINACT) == 0, vp, 2980 ("vnode with usecount and VI_OWEINACT set")); 2981 if (error == 0) { 2982 if (vp->v_iflag & VI_OWEINACT) 2983 vinactive(vp, curthread); 2984 if (func != VPUTX_VUNREF) 2985 VOP_UNLOCK(vp, 0); 2986 } 2987 vdropl(vp); 2988 } 2989 2990 /* 2991 * Vnode put/release. 2992 * If count drops to zero, call inactive routine and return to freelist. 2993 */ 2994 void 2995 vrele(struct vnode *vp) 2996 { 2997 2998 vputx(vp, VPUTX_VRELE); 2999 } 3000 3001 /* 3002 * Release an already locked vnode. This give the same effects as 3003 * unlock+vrele(), but takes less time and avoids releasing and 3004 * re-aquiring the lock (as vrele() acquires the lock internally.) 3005 */ 3006 void 3007 vput(struct vnode *vp) 3008 { 3009 3010 vputx(vp, VPUTX_VPUT); 3011 } 3012 3013 /* 3014 * Release an exclusively locked vnode. Do not unlock the vnode lock. 3015 */ 3016 void 3017 vunref(struct vnode *vp) 3018 { 3019 3020 vputx(vp, VPUTX_VUNREF); 3021 } 3022 3023 /* 3024 * Increase the hold count and activate if this is the first reference. 3025 */ 3026 void 3027 _vhold(struct vnode *vp, bool locked) 3028 { 3029 struct mount *mp; 3030 3031 if (locked) 3032 ASSERT_VI_LOCKED(vp, __func__); 3033 else 3034 ASSERT_VI_UNLOCKED(vp, __func__); 3035 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 3036 if (!locked) { 3037 if (refcount_acquire_if_not_zero(&vp->v_holdcnt)) { 3038 VNODE_REFCOUNT_FENCE_ACQ(); 3039 VNASSERT((vp->v_iflag & VI_FREE) == 0, vp, 3040 ("_vhold: vnode with holdcnt is free")); 3041 return; 3042 } 3043 VI_LOCK(vp); 3044 } 3045 if ((vp->v_iflag & VI_FREE) == 0) { 3046 refcount_acquire(&vp->v_holdcnt); 3047 if (!locked) 3048 VI_UNLOCK(vp); 3049 return; 3050 } 3051 VNASSERT(vp->v_holdcnt == 0, vp, 3052 ("%s: wrong hold count", __func__)); 3053 VNASSERT(vp->v_op != NULL, vp, 3054 ("%s: vnode already reclaimed.", __func__)); 3055 /* 3056 * Remove a vnode from the free list, mark it as in use, 3057 * and put it on the active list. 3058 */ 3059 VNASSERT(vp->v_mount != NULL, vp, 3060 ("_vhold: vnode not on per mount vnode list")); 3061 mp = vp->v_mount; 3062 mtx_lock(&mp->mnt_listmtx); 3063 if ((vp->v_mflag & VMP_TMPMNTFREELIST) != 0) { 3064 TAILQ_REMOVE(&mp->mnt_tmpfreevnodelist, vp, v_actfreelist); 3065 mp->mnt_tmpfreevnodelistsize--; 3066 vp->v_mflag &= ~VMP_TMPMNTFREELIST; 3067 } else { 3068 mtx_lock(&vnode_free_list_mtx); 3069 TAILQ_REMOVE(&vnode_free_list, vp, v_actfreelist); 3070 freevnodes--; 3071 mtx_unlock(&vnode_free_list_mtx); 3072 } 3073 KASSERT((vp->v_iflag & VI_ACTIVE) == 0, 3074 ("Activating already active vnode")); 3075 vp->v_iflag &= ~VI_FREE; 3076 vp->v_iflag |= VI_ACTIVE; 3077 TAILQ_INSERT_HEAD(&mp->mnt_activevnodelist, vp, v_actfreelist); 3078 mp->mnt_activevnodelistsize++; 3079 mtx_unlock(&mp->mnt_listmtx); 3080 refcount_acquire(&vp->v_holdcnt); 3081 if (!locked) 3082 VI_UNLOCK(vp); 3083 } 3084 3085 void 3086 vholdnz(struct vnode *vp) 3087 { 3088 3089 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 3090 #ifdef INVARIANTS 3091 int old = atomic_fetchadd_int(&vp->v_holdcnt, 1); 3092 VNASSERT(old > 0, vp, ("%s: wrong hold count", __func__)); 3093 #else 3094 atomic_add_int(&vp->v_holdcnt, 1); 3095 #endif 3096 } 3097 3098 /* 3099 * Drop the hold count of the vnode. If this is the last reference to 3100 * the vnode we place it on the free list unless it has been vgone'd 3101 * (marked VI_DOOMED) in which case we will free it. 3102 * 3103 * Because the vnode vm object keeps a hold reference on the vnode if 3104 * there is at least one resident non-cached page, the vnode cannot 3105 * leave the active list without the page cleanup done. 3106 */ 3107 void 3108 _vdrop(struct vnode *vp, bool locked) 3109 { 3110 struct bufobj *bo; 3111 struct mount *mp; 3112 int active; 3113 3114 if (locked) 3115 ASSERT_VI_LOCKED(vp, __func__); 3116 else 3117 ASSERT_VI_UNLOCKED(vp, __func__); 3118 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 3119 if (__predict_false((int)vp->v_holdcnt <= 0)) { 3120 vn_printf(vp, "vdrop: holdcnt %d", vp->v_holdcnt); 3121 panic("vdrop: wrong holdcnt"); 3122 } 3123 if (!locked) { 3124 if (refcount_release_if_not_last(&vp->v_holdcnt)) 3125 return; 3126 VI_LOCK(vp); 3127 } 3128 if (refcount_release(&vp->v_holdcnt) == 0) { 3129 VI_UNLOCK(vp); 3130 return; 3131 } 3132 if ((vp->v_iflag & VI_DOOMED) == 0) { 3133 /* 3134 * Mark a vnode as free: remove it from its active list 3135 * and put it up for recycling on the freelist. 3136 */ 3137 VNASSERT(vp->v_op != NULL, vp, 3138 ("vdropl: vnode already reclaimed.")); 3139 VNASSERT((vp->v_iflag & VI_FREE) == 0, vp, 3140 ("vnode already free")); 3141 VNASSERT(vp->v_holdcnt == 0, vp, 3142 ("vdropl: freeing when we shouldn't")); 3143 active = vp->v_iflag & VI_ACTIVE; 3144 if ((vp->v_iflag & VI_OWEINACT) == 0) { 3145 vp->v_iflag &= ~VI_ACTIVE; 3146 mp = vp->v_mount; 3147 if (mp != NULL) { 3148 mtx_lock(&mp->mnt_listmtx); 3149 if (active) { 3150 TAILQ_REMOVE(&mp->mnt_activevnodelist, 3151 vp, v_actfreelist); 3152 mp->mnt_activevnodelistsize--; 3153 } 3154 TAILQ_INSERT_TAIL(&mp->mnt_tmpfreevnodelist, 3155 vp, v_actfreelist); 3156 mp->mnt_tmpfreevnodelistsize++; 3157 vp->v_iflag |= VI_FREE; 3158 vp->v_mflag |= VMP_TMPMNTFREELIST; 3159 VI_UNLOCK(vp); 3160 if (mp->mnt_tmpfreevnodelistsize >= 3161 mnt_free_list_batch) 3162 vnlru_return_batch_locked(mp); 3163 mtx_unlock(&mp->mnt_listmtx); 3164 } else { 3165 VNASSERT(active == 0, vp, 3166 ("vdropl: active vnode not on per mount " 3167 "vnode list")); 3168 mtx_lock(&vnode_free_list_mtx); 3169 TAILQ_INSERT_TAIL(&vnode_free_list, vp, 3170 v_actfreelist); 3171 freevnodes++; 3172 vp->v_iflag |= VI_FREE; 3173 VI_UNLOCK(vp); 3174 mtx_unlock(&vnode_free_list_mtx); 3175 } 3176 } else { 3177 VI_UNLOCK(vp); 3178 counter_u64_add(free_owe_inact, 1); 3179 } 3180 return; 3181 } 3182 /* 3183 * The vnode has been marked for destruction, so free it. 3184 * 3185 * The vnode will be returned to the zone where it will 3186 * normally remain until it is needed for another vnode. We 3187 * need to cleanup (or verify that the cleanup has already 3188 * been done) any residual data left from its current use 3189 * so as not to contaminate the freshly allocated vnode. 3190 */ 3191 CTR2(KTR_VFS, "%s: destroying the vnode %p", __func__, vp); 3192 atomic_subtract_long(&numvnodes, 1); 3193 bo = &vp->v_bufobj; 3194 VNASSERT((vp->v_iflag & VI_FREE) == 0, vp, 3195 ("cleaned vnode still on the free list.")); 3196 VNASSERT(vp->v_data == NULL, vp, ("cleaned vnode isn't")); 3197 VNASSERT(vp->v_holdcnt == 0, vp, ("Non-zero hold count")); 3198 VNASSERT(vp->v_usecount == 0, vp, ("Non-zero use count")); 3199 VNASSERT(vp->v_writecount == 0, vp, ("Non-zero write count")); 3200 VNASSERT(bo->bo_numoutput == 0, vp, ("Clean vnode has pending I/O's")); 3201 VNASSERT(bo->bo_clean.bv_cnt == 0, vp, ("cleanbufcnt not 0")); 3202 VNASSERT(pctrie_is_empty(&bo->bo_clean.bv_root), vp, 3203 ("clean blk trie not empty")); 3204 VNASSERT(bo->bo_dirty.bv_cnt == 0, vp, ("dirtybufcnt not 0")); 3205 VNASSERT(pctrie_is_empty(&bo->bo_dirty.bv_root), vp, 3206 ("dirty blk trie not empty")); 3207 VNASSERT(TAILQ_EMPTY(&vp->v_cache_dst), vp, ("vp has namecache dst")); 3208 VNASSERT(LIST_EMPTY(&vp->v_cache_src), vp, ("vp has namecache src")); 3209 VNASSERT(vp->v_cache_dd == NULL, vp, ("vp has namecache for ..")); 3210 VNASSERT(TAILQ_EMPTY(&vp->v_rl.rl_waiters), vp, 3211 ("Dangling rangelock waiters")); 3212 VI_UNLOCK(vp); 3213 #ifdef MAC 3214 mac_vnode_destroy(vp); 3215 #endif 3216 if (vp->v_pollinfo != NULL) { 3217 destroy_vpollinfo(vp->v_pollinfo); 3218 vp->v_pollinfo = NULL; 3219 } 3220 #ifdef INVARIANTS 3221 /* XXX Elsewhere we detect an already freed vnode via NULL v_op. */ 3222 vp->v_op = NULL; 3223 #endif 3224 vp->v_mountedhere = NULL; 3225 vp->v_unpcb = NULL; 3226 vp->v_rdev = NULL; 3227 vp->v_fifoinfo = NULL; 3228 vp->v_lasta = vp->v_clen = vp->v_cstart = vp->v_lastw = 0; 3229 vp->v_iflag = 0; 3230 vp->v_vflag = 0; 3231 bo->bo_flag = 0; 3232 uma_zfree(vnode_zone, vp); 3233 } 3234 3235 /* 3236 * Call VOP_INACTIVE on the vnode and manage the DOINGINACT and OWEINACT 3237 * flags. DOINGINACT prevents us from recursing in calls to vinactive. 3238 * OWEINACT tracks whether a vnode missed a call to inactive due to a 3239 * failed lock upgrade. 3240 */ 3241 void 3242 vinactive(struct vnode *vp, struct thread *td) 3243 { 3244 struct vm_object *obj; 3245 3246 ASSERT_VOP_ELOCKED(vp, "vinactive"); 3247 ASSERT_VI_LOCKED(vp, "vinactive"); 3248 VNASSERT((vp->v_iflag & VI_DOINGINACT) == 0, vp, 3249 ("vinactive: recursed on VI_DOINGINACT")); 3250 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 3251 vp->v_iflag |= VI_DOINGINACT; 3252 vp->v_iflag &= ~VI_OWEINACT; 3253 VI_UNLOCK(vp); 3254 /* 3255 * Before moving off the active list, we must be sure that any 3256 * modified pages are converted into the vnode's dirty 3257 * buffers, since these will no longer be checked once the 3258 * vnode is on the inactive list. 3259 * 3260 * The write-out of the dirty pages is asynchronous. At the 3261 * point that VOP_INACTIVE() is called, there could still be 3262 * pending I/O and dirty pages in the object. 3263 */ 3264 if ((obj = vp->v_object) != NULL && (vp->v_vflag & VV_NOSYNC) == 0 && 3265 (obj->flags & OBJ_MIGHTBEDIRTY) != 0) { 3266 VM_OBJECT_WLOCK(obj); 3267 vm_object_page_clean(obj, 0, 0, 0); 3268 VM_OBJECT_WUNLOCK(obj); 3269 } 3270 VOP_INACTIVE(vp, td); 3271 VI_LOCK(vp); 3272 VNASSERT(vp->v_iflag & VI_DOINGINACT, vp, 3273 ("vinactive: lost VI_DOINGINACT")); 3274 vp->v_iflag &= ~VI_DOINGINACT; 3275 } 3276 3277 /* 3278 * Remove any vnodes in the vnode table belonging to mount point mp. 3279 * 3280 * If FORCECLOSE is not specified, there should not be any active ones, 3281 * return error if any are found (nb: this is a user error, not a 3282 * system error). If FORCECLOSE is specified, detach any active vnodes 3283 * that are found. 3284 * 3285 * If WRITECLOSE is set, only flush out regular file vnodes open for 3286 * writing. 3287 * 3288 * SKIPSYSTEM causes any vnodes marked VV_SYSTEM to be skipped. 3289 * 3290 * `rootrefs' specifies the base reference count for the root vnode 3291 * of this filesystem. The root vnode is considered busy if its 3292 * v_usecount exceeds this value. On a successful return, vflush(, td) 3293 * will call vrele() on the root vnode exactly rootrefs times. 3294 * If the SKIPSYSTEM or WRITECLOSE flags are specified, rootrefs must 3295 * be zero. 3296 */ 3297 #ifdef DIAGNOSTIC 3298 static int busyprt = 0; /* print out busy vnodes */ 3299 SYSCTL_INT(_debug, OID_AUTO, busyprt, CTLFLAG_RW, &busyprt, 0, "Print out busy vnodes"); 3300 #endif 3301 3302 int 3303 vflush(struct mount *mp, int rootrefs, int flags, struct thread *td) 3304 { 3305 struct vnode *vp, *mvp, *rootvp = NULL; 3306 struct vattr vattr; 3307 int busy = 0, error; 3308 3309 CTR4(KTR_VFS, "%s: mp %p with rootrefs %d and flags %d", __func__, mp, 3310 rootrefs, flags); 3311 if (rootrefs > 0) { 3312 KASSERT((flags & (SKIPSYSTEM | WRITECLOSE)) == 0, 3313 ("vflush: bad args")); 3314 /* 3315 * Get the filesystem root vnode. We can vput() it 3316 * immediately, since with rootrefs > 0, it won't go away. 3317 */ 3318 if ((error = VFS_ROOT(mp, LK_EXCLUSIVE, &rootvp)) != 0) { 3319 CTR2(KTR_VFS, "%s: vfs_root lookup failed with %d", 3320 __func__, error); 3321 return (error); 3322 } 3323 vput(rootvp); 3324 } 3325 loop: 3326 MNT_VNODE_FOREACH_ALL(vp, mp, mvp) { 3327 vholdl(vp); 3328 error = vn_lock(vp, LK_INTERLOCK | LK_EXCLUSIVE); 3329 if (error) { 3330 vdrop(vp); 3331 MNT_VNODE_FOREACH_ALL_ABORT(mp, mvp); 3332 goto loop; 3333 } 3334 /* 3335 * Skip over a vnodes marked VV_SYSTEM. 3336 */ 3337 if ((flags & SKIPSYSTEM) && (vp->v_vflag & VV_SYSTEM)) { 3338 VOP_UNLOCK(vp, 0); 3339 vdrop(vp); 3340 continue; 3341 } 3342 /* 3343 * If WRITECLOSE is set, flush out unlinked but still open 3344 * files (even if open only for reading) and regular file 3345 * vnodes open for writing. 3346 */ 3347 if (flags & WRITECLOSE) { 3348 if (vp->v_object != NULL) { 3349 VM_OBJECT_WLOCK(vp->v_object); 3350 vm_object_page_clean(vp->v_object, 0, 0, 0); 3351 VM_OBJECT_WUNLOCK(vp->v_object); 3352 } 3353 error = VOP_FSYNC(vp, MNT_WAIT, td); 3354 if (error != 0) { 3355 VOP_UNLOCK(vp, 0); 3356 vdrop(vp); 3357 MNT_VNODE_FOREACH_ALL_ABORT(mp, mvp); 3358 return (error); 3359 } 3360 error = VOP_GETATTR(vp, &vattr, td->td_ucred); 3361 VI_LOCK(vp); 3362 3363 if ((vp->v_type == VNON || 3364 (error == 0 && vattr.va_nlink > 0)) && 3365 (vp->v_writecount <= 0 || vp->v_type != VREG)) { 3366 VOP_UNLOCK(vp, 0); 3367 vdropl(vp); 3368 continue; 3369 } 3370 } else 3371 VI_LOCK(vp); 3372 /* 3373 * With v_usecount == 0, all we need to do is clear out the 3374 * vnode data structures and we are done. 3375 * 3376 * If FORCECLOSE is set, forcibly close the vnode. 3377 */ 3378 if (vp->v_usecount == 0 || (flags & FORCECLOSE)) { 3379 vgonel(vp); 3380 } else { 3381 busy++; 3382 #ifdef DIAGNOSTIC 3383 if (busyprt) 3384 vn_printf(vp, "vflush: busy vnode "); 3385 #endif 3386 } 3387 VOP_UNLOCK(vp, 0); 3388 vdropl(vp); 3389 } 3390 if (rootrefs > 0 && (flags & FORCECLOSE) == 0) { 3391 /* 3392 * If just the root vnode is busy, and if its refcount 3393 * is equal to `rootrefs', then go ahead and kill it. 3394 */ 3395 VI_LOCK(rootvp); 3396 KASSERT(busy > 0, ("vflush: not busy")); 3397 VNASSERT(rootvp->v_usecount >= rootrefs, rootvp, 3398 ("vflush: usecount %d < rootrefs %d", 3399 rootvp->v_usecount, rootrefs)); 3400 if (busy == 1 && rootvp->v_usecount == rootrefs) { 3401 VOP_LOCK(rootvp, LK_EXCLUSIVE|LK_INTERLOCK); 3402 vgone(rootvp); 3403 VOP_UNLOCK(rootvp, 0); 3404 busy = 0; 3405 } else 3406 VI_UNLOCK(rootvp); 3407 } 3408 if (busy) { 3409 CTR2(KTR_VFS, "%s: failing as %d vnodes are busy", __func__, 3410 busy); 3411 return (EBUSY); 3412 } 3413 for (; rootrefs > 0; rootrefs--) 3414 vrele(rootvp); 3415 return (0); 3416 } 3417 3418 /* 3419 * Recycle an unused vnode to the front of the free list. 3420 */ 3421 int 3422 vrecycle(struct vnode *vp) 3423 { 3424 int recycled; 3425 3426 VI_LOCK(vp); 3427 recycled = vrecyclel(vp); 3428 VI_UNLOCK(vp); 3429 return (recycled); 3430 } 3431 3432 /* 3433 * vrecycle, with the vp interlock held. 3434 */ 3435 int 3436 vrecyclel(struct vnode *vp) 3437 { 3438 int recycled; 3439 3440 ASSERT_VOP_ELOCKED(vp, __func__); 3441 ASSERT_VI_LOCKED(vp, __func__); 3442 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 3443 recycled = 0; 3444 if (vp->v_usecount == 0) { 3445 recycled = 1; 3446 vgonel(vp); 3447 } 3448 return (recycled); 3449 } 3450 3451 /* 3452 * Eliminate all activity associated with a vnode 3453 * in preparation for reuse. 3454 */ 3455 void 3456 vgone(struct vnode *vp) 3457 { 3458 VI_LOCK(vp); 3459 vgonel(vp); 3460 VI_UNLOCK(vp); 3461 } 3462 3463 static void 3464 notify_lowervp_vfs_dummy(struct mount *mp __unused, 3465 struct vnode *lowervp __unused) 3466 { 3467 } 3468 3469 /* 3470 * Notify upper mounts about reclaimed or unlinked vnode. 3471 */ 3472 void 3473 vfs_notify_upper(struct vnode *vp, int event) 3474 { 3475 static struct vfsops vgonel_vfsops = { 3476 .vfs_reclaim_lowervp = notify_lowervp_vfs_dummy, 3477 .vfs_unlink_lowervp = notify_lowervp_vfs_dummy, 3478 }; 3479 struct mount *mp, *ump, *mmp; 3480 3481 mp = vp->v_mount; 3482 if (mp == NULL) 3483 return; 3484 3485 MNT_ILOCK(mp); 3486 if (TAILQ_EMPTY(&mp->mnt_uppers)) 3487 goto unlock; 3488 MNT_IUNLOCK(mp); 3489 mmp = malloc(sizeof(struct mount), M_TEMP, M_WAITOK | M_ZERO); 3490 mmp->mnt_op = &vgonel_vfsops; 3491 mmp->mnt_kern_flag |= MNTK_MARKER; 3492 MNT_ILOCK(mp); 3493 mp->mnt_kern_flag |= MNTK_VGONE_UPPER; 3494 for (ump = TAILQ_FIRST(&mp->mnt_uppers); ump != NULL;) { 3495 if ((ump->mnt_kern_flag & MNTK_MARKER) != 0) { 3496 ump = TAILQ_NEXT(ump, mnt_upper_link); 3497 continue; 3498 } 3499 TAILQ_INSERT_AFTER(&mp->mnt_uppers, ump, mmp, mnt_upper_link); 3500 MNT_IUNLOCK(mp); 3501 switch (event) { 3502 case VFS_NOTIFY_UPPER_RECLAIM: 3503 VFS_RECLAIM_LOWERVP(ump, vp); 3504 break; 3505 case VFS_NOTIFY_UPPER_UNLINK: 3506 VFS_UNLINK_LOWERVP(ump, vp); 3507 break; 3508 default: 3509 KASSERT(0, ("invalid event %d", event)); 3510 break; 3511 } 3512 MNT_ILOCK(mp); 3513 ump = TAILQ_NEXT(mmp, mnt_upper_link); 3514 TAILQ_REMOVE(&mp->mnt_uppers, mmp, mnt_upper_link); 3515 } 3516 free(mmp, M_TEMP); 3517 mp->mnt_kern_flag &= ~MNTK_VGONE_UPPER; 3518 if ((mp->mnt_kern_flag & MNTK_VGONE_WAITER) != 0) { 3519 mp->mnt_kern_flag &= ~MNTK_VGONE_WAITER; 3520 wakeup(&mp->mnt_uppers); 3521 } 3522 unlock: 3523 MNT_IUNLOCK(mp); 3524 } 3525 3526 /* 3527 * vgone, with the vp interlock held. 3528 */ 3529 static void 3530 vgonel(struct vnode *vp) 3531 { 3532 struct thread *td; 3533 struct mount *mp; 3534 vm_object_t object; 3535 bool active, oweinact; 3536 3537 ASSERT_VOP_ELOCKED(vp, "vgonel"); 3538 ASSERT_VI_LOCKED(vp, "vgonel"); 3539 VNASSERT(vp->v_holdcnt, vp, 3540 ("vgonel: vp %p has no reference.", vp)); 3541 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 3542 td = curthread; 3543 3544 /* 3545 * Don't vgonel if we're already doomed. 3546 */ 3547 if (vp->v_iflag & VI_DOOMED) 3548 return; 3549 vp->v_iflag |= VI_DOOMED; 3550 3551 /* 3552 * Check to see if the vnode is in use. If so, we have to call 3553 * VOP_CLOSE() and VOP_INACTIVE(). 3554 */ 3555 active = vp->v_usecount > 0; 3556 oweinact = (vp->v_iflag & VI_OWEINACT) != 0; 3557 VI_UNLOCK(vp); 3558 vfs_notify_upper(vp, VFS_NOTIFY_UPPER_RECLAIM); 3559 3560 /* 3561 * If purging an active vnode, it must be closed and 3562 * deactivated before being reclaimed. 3563 */ 3564 if (active) 3565 VOP_CLOSE(vp, FNONBLOCK, NOCRED, td); 3566 if (oweinact || active) { 3567 VI_LOCK(vp); 3568 if ((vp->v_iflag & VI_DOINGINACT) == 0) 3569 vinactive(vp, td); 3570 VI_UNLOCK(vp); 3571 } 3572 if (vp->v_type == VSOCK) 3573 vfs_unp_reclaim(vp); 3574 3575 /* 3576 * Clean out any buffers associated with the vnode. 3577 * If the flush fails, just toss the buffers. 3578 */ 3579 mp = NULL; 3580 if (!TAILQ_EMPTY(&vp->v_bufobj.bo_dirty.bv_hd)) 3581 (void) vn_start_secondary_write(vp, &mp, V_WAIT); 3582 if (vinvalbuf(vp, V_SAVE, 0, 0) != 0) { 3583 while (vinvalbuf(vp, 0, 0, 0) != 0) 3584 ; 3585 } 3586 3587 BO_LOCK(&vp->v_bufobj); 3588 KASSERT(TAILQ_EMPTY(&vp->v_bufobj.bo_dirty.bv_hd) && 3589 vp->v_bufobj.bo_dirty.bv_cnt == 0 && 3590 TAILQ_EMPTY(&vp->v_bufobj.bo_clean.bv_hd) && 3591 vp->v_bufobj.bo_clean.bv_cnt == 0, 3592 ("vp %p bufobj not invalidated", vp)); 3593 3594 /* 3595 * For VMIO bufobj, BO_DEAD is set later, or in 3596 * vm_object_terminate() after the object's page queue is 3597 * flushed. 3598 */ 3599 object = vp->v_bufobj.bo_object; 3600 if (object == NULL) 3601 vp->v_bufobj.bo_flag |= BO_DEAD; 3602 BO_UNLOCK(&vp->v_bufobj); 3603 3604 /* 3605 * Handle the VM part. Tmpfs handles v_object on its own (the 3606 * OBJT_VNODE check). Nullfs or other bypassing filesystems 3607 * should not touch the object borrowed from the lower vnode 3608 * (the handle check). 3609 */ 3610 if (object != NULL && object->type == OBJT_VNODE && 3611 object->handle == vp) 3612 vnode_destroy_vobject(vp); 3613 3614 /* 3615 * Reclaim the vnode. 3616 */ 3617 if (VOP_RECLAIM(vp, td)) 3618 panic("vgone: cannot reclaim"); 3619 if (mp != NULL) 3620 vn_finished_secondary_write(mp); 3621 VNASSERT(vp->v_object == NULL, vp, 3622 ("vop_reclaim left v_object vp=%p, tag=%s", vp, vp->v_tag)); 3623 /* 3624 * Clear the advisory locks and wake up waiting threads. 3625 */ 3626 (void)VOP_ADVLOCKPURGE(vp); 3627 vp->v_lockf = NULL; 3628 /* 3629 * Delete from old mount point vnode list. 3630 */ 3631 delmntque(vp); 3632 cache_purge(vp); 3633 /* 3634 * Done with purge, reset to the standard lock and invalidate 3635 * the vnode. 3636 */ 3637 VI_LOCK(vp); 3638 vp->v_vnlock = &vp->v_lock; 3639 vp->v_op = &dead_vnodeops; 3640 vp->v_tag = "none"; 3641 vp->v_type = VBAD; 3642 } 3643 3644 /* 3645 * Calculate the total number of references to a special device. 3646 */ 3647 int 3648 vcount(struct vnode *vp) 3649 { 3650 int count; 3651 3652 dev_lock(); 3653 count = vp->v_rdev->si_usecount; 3654 dev_unlock(); 3655 return (count); 3656 } 3657 3658 /* 3659 * Same as above, but using the struct cdev *as argument 3660 */ 3661 int 3662 count_dev(struct cdev *dev) 3663 { 3664 int count; 3665 3666 dev_lock(); 3667 count = dev->si_usecount; 3668 dev_unlock(); 3669 return(count); 3670 } 3671 3672 /* 3673 * Print out a description of a vnode. 3674 */ 3675 static char *typename[] = 3676 {"VNON", "VREG", "VDIR", "VBLK", "VCHR", "VLNK", "VSOCK", "VFIFO", "VBAD", 3677 "VMARKER"}; 3678 3679 void 3680 vn_printf(struct vnode *vp, const char *fmt, ...) 3681 { 3682 va_list ap; 3683 char buf[256], buf2[16]; 3684 u_long flags; 3685 3686 va_start(ap, fmt); 3687 vprintf(fmt, ap); 3688 va_end(ap); 3689 printf("%p: ", (void *)vp); 3690 printf("tag %s, type %s\n", vp->v_tag, typename[vp->v_type]); 3691 printf(" usecount %d, writecount %d, refcount %d", 3692 vp->v_usecount, vp->v_writecount, vp->v_holdcnt); 3693 switch (vp->v_type) { 3694 case VDIR: 3695 printf(" mountedhere %p\n", vp->v_mountedhere); 3696 break; 3697 case VCHR: 3698 printf(" rdev %p\n", vp->v_rdev); 3699 break; 3700 case VSOCK: 3701 printf(" socket %p\n", vp->v_unpcb); 3702 break; 3703 case VFIFO: 3704 printf(" fifoinfo %p\n", vp->v_fifoinfo); 3705 break; 3706 default: 3707 printf("\n"); 3708 break; 3709 } 3710 buf[0] = '\0'; 3711 buf[1] = '\0'; 3712 if (vp->v_vflag & VV_ROOT) 3713 strlcat(buf, "|VV_ROOT", sizeof(buf)); 3714 if (vp->v_vflag & VV_ISTTY) 3715 strlcat(buf, "|VV_ISTTY", sizeof(buf)); 3716 if (vp->v_vflag & VV_NOSYNC) 3717 strlcat(buf, "|VV_NOSYNC", sizeof(buf)); 3718 if (vp->v_vflag & VV_ETERNALDEV) 3719 strlcat(buf, "|VV_ETERNALDEV", sizeof(buf)); 3720 if (vp->v_vflag & VV_CACHEDLABEL) 3721 strlcat(buf, "|VV_CACHEDLABEL", sizeof(buf)); 3722 if (vp->v_vflag & VV_COPYONWRITE) 3723 strlcat(buf, "|VV_COPYONWRITE", sizeof(buf)); 3724 if (vp->v_vflag & VV_SYSTEM) 3725 strlcat(buf, "|VV_SYSTEM", sizeof(buf)); 3726 if (vp->v_vflag & VV_PROCDEP) 3727 strlcat(buf, "|VV_PROCDEP", sizeof(buf)); 3728 if (vp->v_vflag & VV_NOKNOTE) 3729 strlcat(buf, "|VV_NOKNOTE", sizeof(buf)); 3730 if (vp->v_vflag & VV_DELETED) 3731 strlcat(buf, "|VV_DELETED", sizeof(buf)); 3732 if (vp->v_vflag & VV_MD) 3733 strlcat(buf, "|VV_MD", sizeof(buf)); 3734 if (vp->v_vflag & VV_FORCEINSMQ) 3735 strlcat(buf, "|VV_FORCEINSMQ", sizeof(buf)); 3736 flags = vp->v_vflag & ~(VV_ROOT | VV_ISTTY | VV_NOSYNC | VV_ETERNALDEV | 3737 VV_CACHEDLABEL | VV_COPYONWRITE | VV_SYSTEM | VV_PROCDEP | 3738 VV_NOKNOTE | VV_DELETED | VV_MD | VV_FORCEINSMQ); 3739 if (flags != 0) { 3740 snprintf(buf2, sizeof(buf2), "|VV(0x%lx)", flags); 3741 strlcat(buf, buf2, sizeof(buf)); 3742 } 3743 if (vp->v_iflag & VI_MOUNT) 3744 strlcat(buf, "|VI_MOUNT", sizeof(buf)); 3745 if (vp->v_iflag & VI_DOOMED) 3746 strlcat(buf, "|VI_DOOMED", sizeof(buf)); 3747 if (vp->v_iflag & VI_FREE) 3748 strlcat(buf, "|VI_FREE", sizeof(buf)); 3749 if (vp->v_iflag & VI_ACTIVE) 3750 strlcat(buf, "|VI_ACTIVE", sizeof(buf)); 3751 if (vp->v_iflag & VI_DOINGINACT) 3752 strlcat(buf, "|VI_DOINGINACT", sizeof(buf)); 3753 if (vp->v_iflag & VI_OWEINACT) 3754 strlcat(buf, "|VI_OWEINACT", sizeof(buf)); 3755 flags = vp->v_iflag & ~(VI_MOUNT | VI_DOOMED | VI_FREE | 3756 VI_ACTIVE | VI_DOINGINACT | VI_OWEINACT); 3757 if (flags != 0) { 3758 snprintf(buf2, sizeof(buf2), "|VI(0x%lx)", flags); 3759 strlcat(buf, buf2, sizeof(buf)); 3760 } 3761 printf(" flags (%s)\n", buf + 1); 3762 if (mtx_owned(VI_MTX(vp))) 3763 printf(" VI_LOCKed"); 3764 if (vp->v_object != NULL) 3765 printf(" v_object %p ref %d pages %d " 3766 "cleanbuf %d dirtybuf %d\n", 3767 vp->v_object, vp->v_object->ref_count, 3768 vp->v_object->resident_page_count, 3769 vp->v_bufobj.bo_clean.bv_cnt, 3770 vp->v_bufobj.bo_dirty.bv_cnt); 3771 printf(" "); 3772 lockmgr_printinfo(vp->v_vnlock); 3773 if (vp->v_data != NULL) 3774 VOP_PRINT(vp); 3775 } 3776 3777 #ifdef DDB 3778 /* 3779 * List all of the locked vnodes in the system. 3780 * Called when debugging the kernel. 3781 */ 3782 DB_SHOW_COMMAND(lockedvnods, lockedvnodes) 3783 { 3784 struct mount *mp; 3785 struct vnode *vp; 3786 3787 /* 3788 * Note: because this is DDB, we can't obey the locking semantics 3789 * for these structures, which means we could catch an inconsistent 3790 * state and dereference a nasty pointer. Not much to be done 3791 * about that. 3792 */ 3793 db_printf("Locked vnodes\n"); 3794 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 3795 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) { 3796 if (vp->v_type != VMARKER && VOP_ISLOCKED(vp)) 3797 vn_printf(vp, "vnode "); 3798 } 3799 } 3800 } 3801 3802 /* 3803 * Show details about the given vnode. 3804 */ 3805 DB_SHOW_COMMAND(vnode, db_show_vnode) 3806 { 3807 struct vnode *vp; 3808 3809 if (!have_addr) 3810 return; 3811 vp = (struct vnode *)addr; 3812 vn_printf(vp, "vnode "); 3813 } 3814 3815 /* 3816 * Show details about the given mount point. 3817 */ 3818 DB_SHOW_COMMAND(mount, db_show_mount) 3819 { 3820 struct mount *mp; 3821 struct vfsopt *opt; 3822 struct statfs *sp; 3823 struct vnode *vp; 3824 char buf[512]; 3825 uint64_t mflags; 3826 u_int flags; 3827 3828 if (!have_addr) { 3829 /* No address given, print short info about all mount points. */ 3830 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 3831 db_printf("%p %s on %s (%s)\n", mp, 3832 mp->mnt_stat.f_mntfromname, 3833 mp->mnt_stat.f_mntonname, 3834 mp->mnt_stat.f_fstypename); 3835 if (db_pager_quit) 3836 break; 3837 } 3838 db_printf("\nMore info: show mount <addr>\n"); 3839 return; 3840 } 3841 3842 mp = (struct mount *)addr; 3843 db_printf("%p %s on %s (%s)\n", mp, mp->mnt_stat.f_mntfromname, 3844 mp->mnt_stat.f_mntonname, mp->mnt_stat.f_fstypename); 3845 3846 buf[0] = '\0'; 3847 mflags = mp->mnt_flag; 3848 #define MNT_FLAG(flag) do { \ 3849 if (mflags & (flag)) { \ 3850 if (buf[0] != '\0') \ 3851 strlcat(buf, ", ", sizeof(buf)); \ 3852 strlcat(buf, (#flag) + 4, sizeof(buf)); \ 3853 mflags &= ~(flag); \ 3854 } \ 3855 } while (0) 3856 MNT_FLAG(MNT_RDONLY); 3857 MNT_FLAG(MNT_SYNCHRONOUS); 3858 MNT_FLAG(MNT_NOEXEC); 3859 MNT_FLAG(MNT_NOSUID); 3860 MNT_FLAG(MNT_NFS4ACLS); 3861 MNT_FLAG(MNT_UNION); 3862 MNT_FLAG(MNT_ASYNC); 3863 MNT_FLAG(MNT_SUIDDIR); 3864 MNT_FLAG(MNT_SOFTDEP); 3865 MNT_FLAG(MNT_NOSYMFOLLOW); 3866 MNT_FLAG(MNT_GJOURNAL); 3867 MNT_FLAG(MNT_MULTILABEL); 3868 MNT_FLAG(MNT_ACLS); 3869 MNT_FLAG(MNT_NOATIME); 3870 MNT_FLAG(MNT_NOCLUSTERR); 3871 MNT_FLAG(MNT_NOCLUSTERW); 3872 MNT_FLAG(MNT_SUJ); 3873 MNT_FLAG(MNT_EXRDONLY); 3874 MNT_FLAG(MNT_EXPORTED); 3875 MNT_FLAG(MNT_DEFEXPORTED); 3876 MNT_FLAG(MNT_EXPORTANON); 3877 MNT_FLAG(MNT_EXKERB); 3878 MNT_FLAG(MNT_EXPUBLIC); 3879 MNT_FLAG(MNT_LOCAL); 3880 MNT_FLAG(MNT_QUOTA); 3881 MNT_FLAG(MNT_ROOTFS); 3882 MNT_FLAG(MNT_USER); 3883 MNT_FLAG(MNT_IGNORE); 3884 MNT_FLAG(MNT_UPDATE); 3885 MNT_FLAG(MNT_DELEXPORT); 3886 MNT_FLAG(MNT_RELOAD); 3887 MNT_FLAG(MNT_FORCE); 3888 MNT_FLAG(MNT_SNAPSHOT); 3889 MNT_FLAG(MNT_BYFSID); 3890 #undef MNT_FLAG 3891 if (mflags != 0) { 3892 if (buf[0] != '\0') 3893 strlcat(buf, ", ", sizeof(buf)); 3894 snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf), 3895 "0x%016jx", mflags); 3896 } 3897 db_printf(" mnt_flag = %s\n", buf); 3898 3899 buf[0] = '\0'; 3900 flags = mp->mnt_kern_flag; 3901 #define MNT_KERN_FLAG(flag) do { \ 3902 if (flags & (flag)) { \ 3903 if (buf[0] != '\0') \ 3904 strlcat(buf, ", ", sizeof(buf)); \ 3905 strlcat(buf, (#flag) + 5, sizeof(buf)); \ 3906 flags &= ~(flag); \ 3907 } \ 3908 } while (0) 3909 MNT_KERN_FLAG(MNTK_UNMOUNTF); 3910 MNT_KERN_FLAG(MNTK_ASYNC); 3911 MNT_KERN_FLAG(MNTK_SOFTDEP); 3912 MNT_KERN_FLAG(MNTK_DRAINING); 3913 MNT_KERN_FLAG(MNTK_REFEXPIRE); 3914 MNT_KERN_FLAG(MNTK_EXTENDED_SHARED); 3915 MNT_KERN_FLAG(MNTK_SHARED_WRITES); 3916 MNT_KERN_FLAG(MNTK_NO_IOPF); 3917 MNT_KERN_FLAG(MNTK_VGONE_UPPER); 3918 MNT_KERN_FLAG(MNTK_VGONE_WAITER); 3919 MNT_KERN_FLAG(MNTK_LOOKUP_EXCL_DOTDOT); 3920 MNT_KERN_FLAG(MNTK_MARKER); 3921 MNT_KERN_FLAG(MNTK_USES_BCACHE); 3922 MNT_KERN_FLAG(MNTK_NOASYNC); 3923 MNT_KERN_FLAG(MNTK_UNMOUNT); 3924 MNT_KERN_FLAG(MNTK_MWAIT); 3925 MNT_KERN_FLAG(MNTK_SUSPEND); 3926 MNT_KERN_FLAG(MNTK_SUSPEND2); 3927 MNT_KERN_FLAG(MNTK_SUSPENDED); 3928 MNT_KERN_FLAG(MNTK_LOOKUP_SHARED); 3929 MNT_KERN_FLAG(MNTK_NOKNOTE); 3930 #undef MNT_KERN_FLAG 3931 if (flags != 0) { 3932 if (buf[0] != '\0') 3933 strlcat(buf, ", ", sizeof(buf)); 3934 snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf), 3935 "0x%08x", flags); 3936 } 3937 db_printf(" mnt_kern_flag = %s\n", buf); 3938 3939 db_printf(" mnt_opt = "); 3940 opt = TAILQ_FIRST(mp->mnt_opt); 3941 if (opt != NULL) { 3942 db_printf("%s", opt->name); 3943 opt = TAILQ_NEXT(opt, link); 3944 while (opt != NULL) { 3945 db_printf(", %s", opt->name); 3946 opt = TAILQ_NEXT(opt, link); 3947 } 3948 } 3949 db_printf("\n"); 3950 3951 sp = &mp->mnt_stat; 3952 db_printf(" mnt_stat = { version=%u type=%u flags=0x%016jx " 3953 "bsize=%ju iosize=%ju blocks=%ju bfree=%ju bavail=%jd files=%ju " 3954 "ffree=%jd syncwrites=%ju asyncwrites=%ju syncreads=%ju " 3955 "asyncreads=%ju namemax=%u owner=%u fsid=[%d, %d] }\n", 3956 (u_int)sp->f_version, (u_int)sp->f_type, (uintmax_t)sp->f_flags, 3957 (uintmax_t)sp->f_bsize, (uintmax_t)sp->f_iosize, 3958 (uintmax_t)sp->f_blocks, (uintmax_t)sp->f_bfree, 3959 (intmax_t)sp->f_bavail, (uintmax_t)sp->f_files, 3960 (intmax_t)sp->f_ffree, (uintmax_t)sp->f_syncwrites, 3961 (uintmax_t)sp->f_asyncwrites, (uintmax_t)sp->f_syncreads, 3962 (uintmax_t)sp->f_asyncreads, (u_int)sp->f_namemax, 3963 (u_int)sp->f_owner, (int)sp->f_fsid.val[0], (int)sp->f_fsid.val[1]); 3964 3965 db_printf(" mnt_cred = { uid=%u ruid=%u", 3966 (u_int)mp->mnt_cred->cr_uid, (u_int)mp->mnt_cred->cr_ruid); 3967 if (jailed(mp->mnt_cred)) 3968 db_printf(", jail=%d", mp->mnt_cred->cr_prison->pr_id); 3969 db_printf(" }\n"); 3970 db_printf(" mnt_ref = %d\n", mp->mnt_ref); 3971 db_printf(" mnt_gen = %d\n", mp->mnt_gen); 3972 db_printf(" mnt_nvnodelistsize = %d\n", mp->mnt_nvnodelistsize); 3973 db_printf(" mnt_activevnodelistsize = %d\n", 3974 mp->mnt_activevnodelistsize); 3975 db_printf(" mnt_writeopcount = %d\n", mp->mnt_writeopcount); 3976 db_printf(" mnt_maxsymlinklen = %d\n", mp->mnt_maxsymlinklen); 3977 db_printf(" mnt_iosize_max = %d\n", mp->mnt_iosize_max); 3978 db_printf(" mnt_hashseed = %u\n", mp->mnt_hashseed); 3979 db_printf(" mnt_lockref = %d\n", mp->mnt_lockref); 3980 db_printf(" mnt_secondary_writes = %d\n", mp->mnt_secondary_writes); 3981 db_printf(" mnt_secondary_accwrites = %d\n", 3982 mp->mnt_secondary_accwrites); 3983 db_printf(" mnt_gjprovider = %s\n", 3984 mp->mnt_gjprovider != NULL ? mp->mnt_gjprovider : "NULL"); 3985 3986 db_printf("\n\nList of active vnodes\n"); 3987 TAILQ_FOREACH(vp, &mp->mnt_activevnodelist, v_actfreelist) { 3988 if (vp->v_type != VMARKER) { 3989 vn_printf(vp, "vnode "); 3990 if (db_pager_quit) 3991 break; 3992 } 3993 } 3994 db_printf("\n\nList of inactive vnodes\n"); 3995 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) { 3996 if (vp->v_type != VMARKER && (vp->v_iflag & VI_ACTIVE) == 0) { 3997 vn_printf(vp, "vnode "); 3998 if (db_pager_quit) 3999 break; 4000 } 4001 } 4002 } 4003 #endif /* DDB */ 4004 4005 /* 4006 * Fill in a struct xvfsconf based on a struct vfsconf. 4007 */ 4008 static int 4009 vfsconf2x(struct sysctl_req *req, struct vfsconf *vfsp) 4010 { 4011 struct xvfsconf xvfsp; 4012 4013 bzero(&xvfsp, sizeof(xvfsp)); 4014 strcpy(xvfsp.vfc_name, vfsp->vfc_name); 4015 xvfsp.vfc_typenum = vfsp->vfc_typenum; 4016 xvfsp.vfc_refcount = vfsp->vfc_refcount; 4017 xvfsp.vfc_flags = vfsp->vfc_flags; 4018 /* 4019 * These are unused in userland, we keep them 4020 * to not break binary compatibility. 4021 */ 4022 xvfsp.vfc_vfsops = NULL; 4023 xvfsp.vfc_next = NULL; 4024 return (SYSCTL_OUT(req, &xvfsp, sizeof(xvfsp))); 4025 } 4026 4027 #ifdef COMPAT_FREEBSD32 4028 struct xvfsconf32 { 4029 uint32_t vfc_vfsops; 4030 char vfc_name[MFSNAMELEN]; 4031 int32_t vfc_typenum; 4032 int32_t vfc_refcount; 4033 int32_t vfc_flags; 4034 uint32_t vfc_next; 4035 }; 4036 4037 static int 4038 vfsconf2x32(struct sysctl_req *req, struct vfsconf *vfsp) 4039 { 4040 struct xvfsconf32 xvfsp; 4041 4042 bzero(&xvfsp, sizeof(xvfsp)); 4043 strcpy(xvfsp.vfc_name, vfsp->vfc_name); 4044 xvfsp.vfc_typenum = vfsp->vfc_typenum; 4045 xvfsp.vfc_refcount = vfsp->vfc_refcount; 4046 xvfsp.vfc_flags = vfsp->vfc_flags; 4047 return (SYSCTL_OUT(req, &xvfsp, sizeof(xvfsp))); 4048 } 4049 #endif 4050 4051 /* 4052 * Top level filesystem related information gathering. 4053 */ 4054 static int 4055 sysctl_vfs_conflist(SYSCTL_HANDLER_ARGS) 4056 { 4057 struct vfsconf *vfsp; 4058 int error; 4059 4060 error = 0; 4061 vfsconf_slock(); 4062 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) { 4063 #ifdef COMPAT_FREEBSD32 4064 if (req->flags & SCTL_MASK32) 4065 error = vfsconf2x32(req, vfsp); 4066 else 4067 #endif 4068 error = vfsconf2x(req, vfsp); 4069 if (error) 4070 break; 4071 } 4072 vfsconf_sunlock(); 4073 return (error); 4074 } 4075 4076 SYSCTL_PROC(_vfs, OID_AUTO, conflist, CTLTYPE_OPAQUE | CTLFLAG_RD | 4077 CTLFLAG_MPSAFE, NULL, 0, sysctl_vfs_conflist, 4078 "S,xvfsconf", "List of all configured filesystems"); 4079 4080 #ifndef BURN_BRIDGES 4081 static int sysctl_ovfs_conf(SYSCTL_HANDLER_ARGS); 4082 4083 static int 4084 vfs_sysctl(SYSCTL_HANDLER_ARGS) 4085 { 4086 int *name = (int *)arg1 - 1; /* XXX */ 4087 u_int namelen = arg2 + 1; /* XXX */ 4088 struct vfsconf *vfsp; 4089 4090 log(LOG_WARNING, "userland calling deprecated sysctl, " 4091 "please rebuild world\n"); 4092 4093 #if 1 || defined(COMPAT_PRELITE2) 4094 /* Resolve ambiguity between VFS_VFSCONF and VFS_GENERIC. */ 4095 if (namelen == 1) 4096 return (sysctl_ovfs_conf(oidp, arg1, arg2, req)); 4097 #endif 4098 4099 switch (name[1]) { 4100 case VFS_MAXTYPENUM: 4101 if (namelen != 2) 4102 return (ENOTDIR); 4103 return (SYSCTL_OUT(req, &maxvfsconf, sizeof(int))); 4104 case VFS_CONF: 4105 if (namelen != 3) 4106 return (ENOTDIR); /* overloaded */ 4107 vfsconf_slock(); 4108 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) { 4109 if (vfsp->vfc_typenum == name[2]) 4110 break; 4111 } 4112 vfsconf_sunlock(); 4113 if (vfsp == NULL) 4114 return (EOPNOTSUPP); 4115 #ifdef COMPAT_FREEBSD32 4116 if (req->flags & SCTL_MASK32) 4117 return (vfsconf2x32(req, vfsp)); 4118 else 4119 #endif 4120 return (vfsconf2x(req, vfsp)); 4121 } 4122 return (EOPNOTSUPP); 4123 } 4124 4125 static SYSCTL_NODE(_vfs, VFS_GENERIC, generic, CTLFLAG_RD | CTLFLAG_SKIP | 4126 CTLFLAG_MPSAFE, vfs_sysctl, 4127 "Generic filesystem"); 4128 4129 #if 1 || defined(COMPAT_PRELITE2) 4130 4131 static int 4132 sysctl_ovfs_conf(SYSCTL_HANDLER_ARGS) 4133 { 4134 int error; 4135 struct vfsconf *vfsp; 4136 struct ovfsconf ovfs; 4137 4138 vfsconf_slock(); 4139 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) { 4140 bzero(&ovfs, sizeof(ovfs)); 4141 ovfs.vfc_vfsops = vfsp->vfc_vfsops; /* XXX used as flag */ 4142 strcpy(ovfs.vfc_name, vfsp->vfc_name); 4143 ovfs.vfc_index = vfsp->vfc_typenum; 4144 ovfs.vfc_refcount = vfsp->vfc_refcount; 4145 ovfs.vfc_flags = vfsp->vfc_flags; 4146 error = SYSCTL_OUT(req, &ovfs, sizeof ovfs); 4147 if (error != 0) { 4148 vfsconf_sunlock(); 4149 return (error); 4150 } 4151 } 4152 vfsconf_sunlock(); 4153 return (0); 4154 } 4155 4156 #endif /* 1 || COMPAT_PRELITE2 */ 4157 #endif /* !BURN_BRIDGES */ 4158 4159 #define KINFO_VNODESLOP 10 4160 #ifdef notyet 4161 /* 4162 * Dump vnode list (via sysctl). 4163 */ 4164 /* ARGSUSED */ 4165 static int 4166 sysctl_vnode(SYSCTL_HANDLER_ARGS) 4167 { 4168 struct xvnode *xvn; 4169 struct mount *mp; 4170 struct vnode *vp; 4171 int error, len, n; 4172 4173 /* 4174 * Stale numvnodes access is not fatal here. 4175 */ 4176 req->lock = 0; 4177 len = (numvnodes + KINFO_VNODESLOP) * sizeof *xvn; 4178 if (!req->oldptr) 4179 /* Make an estimate */ 4180 return (SYSCTL_OUT(req, 0, len)); 4181 4182 error = sysctl_wire_old_buffer(req, 0); 4183 if (error != 0) 4184 return (error); 4185 xvn = malloc(len, M_TEMP, M_ZERO | M_WAITOK); 4186 n = 0; 4187 mtx_lock(&mountlist_mtx); 4188 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 4189 if (vfs_busy(mp, MBF_NOWAIT | MBF_MNTLSTLOCK)) 4190 continue; 4191 MNT_ILOCK(mp); 4192 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) { 4193 if (n == len) 4194 break; 4195 vref(vp); 4196 xvn[n].xv_size = sizeof *xvn; 4197 xvn[n].xv_vnode = vp; 4198 xvn[n].xv_id = 0; /* XXX compat */ 4199 #define XV_COPY(field) xvn[n].xv_##field = vp->v_##field 4200 XV_COPY(usecount); 4201 XV_COPY(writecount); 4202 XV_COPY(holdcnt); 4203 XV_COPY(mount); 4204 XV_COPY(numoutput); 4205 XV_COPY(type); 4206 #undef XV_COPY 4207 xvn[n].xv_flag = vp->v_vflag; 4208 4209 switch (vp->v_type) { 4210 case VREG: 4211 case VDIR: 4212 case VLNK: 4213 break; 4214 case VBLK: 4215 case VCHR: 4216 if (vp->v_rdev == NULL) { 4217 vrele(vp); 4218 continue; 4219 } 4220 xvn[n].xv_dev = dev2udev(vp->v_rdev); 4221 break; 4222 case VSOCK: 4223 xvn[n].xv_socket = vp->v_socket; 4224 break; 4225 case VFIFO: 4226 xvn[n].xv_fifo = vp->v_fifoinfo; 4227 break; 4228 case VNON: 4229 case VBAD: 4230 default: 4231 /* shouldn't happen? */ 4232 vrele(vp); 4233 continue; 4234 } 4235 vrele(vp); 4236 ++n; 4237 } 4238 MNT_IUNLOCK(mp); 4239 mtx_lock(&mountlist_mtx); 4240 vfs_unbusy(mp); 4241 if (n == len) 4242 break; 4243 } 4244 mtx_unlock(&mountlist_mtx); 4245 4246 error = SYSCTL_OUT(req, xvn, n * sizeof *xvn); 4247 free(xvn, M_TEMP); 4248 return (error); 4249 } 4250 4251 SYSCTL_PROC(_kern, KERN_VNODE, vnode, CTLTYPE_OPAQUE | CTLFLAG_RD | 4252 CTLFLAG_MPSAFE, 0, 0, sysctl_vnode, "S,xvnode", 4253 ""); 4254 #endif 4255 4256 static void 4257 unmount_or_warn(struct mount *mp) 4258 { 4259 int error; 4260 4261 error = dounmount(mp, MNT_FORCE, curthread); 4262 if (error != 0) { 4263 printf("unmount of %s failed (", mp->mnt_stat.f_mntonname); 4264 if (error == EBUSY) 4265 printf("BUSY)\n"); 4266 else 4267 printf("%d)\n", error); 4268 } 4269 } 4270 4271 /* 4272 * Unmount all filesystems. The list is traversed in reverse order 4273 * of mounting to avoid dependencies. 4274 */ 4275 void 4276 vfs_unmountall(void) 4277 { 4278 struct mount *mp, *tmp; 4279 4280 CTR1(KTR_VFS, "%s: unmounting all filesystems", __func__); 4281 4282 /* 4283 * Since this only runs when rebooting, it is not interlocked. 4284 */ 4285 TAILQ_FOREACH_REVERSE_SAFE(mp, &mountlist, mntlist, mnt_list, tmp) { 4286 vfs_ref(mp); 4287 4288 /* 4289 * Forcibly unmounting "/dev" before "/" would prevent clean 4290 * unmount of the latter. 4291 */ 4292 if (mp == rootdevmp) 4293 continue; 4294 4295 unmount_or_warn(mp); 4296 } 4297 4298 if (rootdevmp != NULL) 4299 unmount_or_warn(rootdevmp); 4300 } 4301 4302 /* 4303 * perform msync on all vnodes under a mount point 4304 * the mount point must be locked. 4305 */ 4306 void 4307 vfs_msync(struct mount *mp, int flags) 4308 { 4309 struct vnode *vp, *mvp; 4310 struct vm_object *obj; 4311 4312 CTR2(KTR_VFS, "%s: mp %p", __func__, mp); 4313 4314 vnlru_return_batch(mp); 4315 4316 MNT_VNODE_FOREACH_ACTIVE(vp, mp, mvp) { 4317 obj = vp->v_object; 4318 if (obj != NULL && (obj->flags & OBJ_MIGHTBEDIRTY) != 0 && 4319 (flags == MNT_WAIT || VOP_ISLOCKED(vp) == 0)) { 4320 if (!vget(vp, 4321 LK_EXCLUSIVE | LK_RETRY | LK_INTERLOCK, 4322 curthread)) { 4323 if (vp->v_vflag & VV_NOSYNC) { /* unlinked */ 4324 vput(vp); 4325 continue; 4326 } 4327 4328 obj = vp->v_object; 4329 if (obj != NULL) { 4330 VM_OBJECT_WLOCK(obj); 4331 vm_object_page_clean(obj, 0, 0, 4332 flags == MNT_WAIT ? 4333 OBJPC_SYNC : OBJPC_NOSYNC); 4334 VM_OBJECT_WUNLOCK(obj); 4335 } 4336 vput(vp); 4337 } 4338 } else 4339 VI_UNLOCK(vp); 4340 } 4341 } 4342 4343 static void 4344 destroy_vpollinfo_free(struct vpollinfo *vi) 4345 { 4346 4347 knlist_destroy(&vi->vpi_selinfo.si_note); 4348 mtx_destroy(&vi->vpi_lock); 4349 uma_zfree(vnodepoll_zone, vi); 4350 } 4351 4352 static void 4353 destroy_vpollinfo(struct vpollinfo *vi) 4354 { 4355 4356 knlist_clear(&vi->vpi_selinfo.si_note, 1); 4357 seldrain(&vi->vpi_selinfo); 4358 destroy_vpollinfo_free(vi); 4359 } 4360 4361 /* 4362 * Initialize per-vnode helper structure to hold poll-related state. 4363 */ 4364 void 4365 v_addpollinfo(struct vnode *vp) 4366 { 4367 struct vpollinfo *vi; 4368 4369 if (vp->v_pollinfo != NULL) 4370 return; 4371 vi = uma_zalloc(vnodepoll_zone, M_WAITOK | M_ZERO); 4372 mtx_init(&vi->vpi_lock, "vnode pollinfo", NULL, MTX_DEF); 4373 knlist_init(&vi->vpi_selinfo.si_note, vp, vfs_knllock, 4374 vfs_knlunlock, vfs_knl_assert_locked, vfs_knl_assert_unlocked); 4375 VI_LOCK(vp); 4376 if (vp->v_pollinfo != NULL) { 4377 VI_UNLOCK(vp); 4378 destroy_vpollinfo_free(vi); 4379 return; 4380 } 4381 vp->v_pollinfo = vi; 4382 VI_UNLOCK(vp); 4383 } 4384 4385 /* 4386 * Record a process's interest in events which might happen to 4387 * a vnode. Because poll uses the historic select-style interface 4388 * internally, this routine serves as both the ``check for any 4389 * pending events'' and the ``record my interest in future events'' 4390 * functions. (These are done together, while the lock is held, 4391 * to avoid race conditions.) 4392 */ 4393 int 4394 vn_pollrecord(struct vnode *vp, struct thread *td, int events) 4395 { 4396 4397 v_addpollinfo(vp); 4398 mtx_lock(&vp->v_pollinfo->vpi_lock); 4399 if (vp->v_pollinfo->vpi_revents & events) { 4400 /* 4401 * This leaves events we are not interested 4402 * in available for the other process which 4403 * which presumably had requested them 4404 * (otherwise they would never have been 4405 * recorded). 4406 */ 4407 events &= vp->v_pollinfo->vpi_revents; 4408 vp->v_pollinfo->vpi_revents &= ~events; 4409 4410 mtx_unlock(&vp->v_pollinfo->vpi_lock); 4411 return (events); 4412 } 4413 vp->v_pollinfo->vpi_events |= events; 4414 selrecord(td, &vp->v_pollinfo->vpi_selinfo); 4415 mtx_unlock(&vp->v_pollinfo->vpi_lock); 4416 return (0); 4417 } 4418 4419 /* 4420 * Routine to create and manage a filesystem syncer vnode. 4421 */ 4422 #define sync_close ((int (*)(struct vop_close_args *))nullop) 4423 static int sync_fsync(struct vop_fsync_args *); 4424 static int sync_inactive(struct vop_inactive_args *); 4425 static int sync_reclaim(struct vop_reclaim_args *); 4426 4427 static struct vop_vector sync_vnodeops = { 4428 .vop_bypass = VOP_EOPNOTSUPP, 4429 .vop_close = sync_close, /* close */ 4430 .vop_fsync = sync_fsync, /* fsync */ 4431 .vop_inactive = sync_inactive, /* inactive */ 4432 .vop_need_inactive = vop_stdneed_inactive, /* need_inactive */ 4433 .vop_reclaim = sync_reclaim, /* reclaim */ 4434 .vop_lock1 = vop_stdlock, /* lock */ 4435 .vop_unlock = vop_stdunlock, /* unlock */ 4436 .vop_islocked = vop_stdislocked, /* islocked */ 4437 }; 4438 4439 /* 4440 * Create a new filesystem syncer vnode for the specified mount point. 4441 */ 4442 void 4443 vfs_allocate_syncvnode(struct mount *mp) 4444 { 4445 struct vnode *vp; 4446 struct bufobj *bo; 4447 static long start, incr, next; 4448 int error; 4449 4450 /* Allocate a new vnode */ 4451 error = getnewvnode("syncer", mp, &sync_vnodeops, &vp); 4452 if (error != 0) 4453 panic("vfs_allocate_syncvnode: getnewvnode() failed"); 4454 vp->v_type = VNON; 4455 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 4456 vp->v_vflag |= VV_FORCEINSMQ; 4457 error = insmntque(vp, mp); 4458 if (error != 0) 4459 panic("vfs_allocate_syncvnode: insmntque() failed"); 4460 vp->v_vflag &= ~VV_FORCEINSMQ; 4461 VOP_UNLOCK(vp, 0); 4462 /* 4463 * Place the vnode onto the syncer worklist. We attempt to 4464 * scatter them about on the list so that they will go off 4465 * at evenly distributed times even if all the filesystems 4466 * are mounted at once. 4467 */ 4468 next += incr; 4469 if (next == 0 || next > syncer_maxdelay) { 4470 start /= 2; 4471 incr /= 2; 4472 if (start == 0) { 4473 start = syncer_maxdelay / 2; 4474 incr = syncer_maxdelay; 4475 } 4476 next = start; 4477 } 4478 bo = &vp->v_bufobj; 4479 BO_LOCK(bo); 4480 vn_syncer_add_to_worklist(bo, syncdelay > 0 ? next % syncdelay : 0); 4481 /* XXX - vn_syncer_add_to_worklist() also grabs and drops sync_mtx. */ 4482 mtx_lock(&sync_mtx); 4483 sync_vnode_count++; 4484 if (mp->mnt_syncer == NULL) { 4485 mp->mnt_syncer = vp; 4486 vp = NULL; 4487 } 4488 mtx_unlock(&sync_mtx); 4489 BO_UNLOCK(bo); 4490 if (vp != NULL) { 4491 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 4492 vgone(vp); 4493 vput(vp); 4494 } 4495 } 4496 4497 void 4498 vfs_deallocate_syncvnode(struct mount *mp) 4499 { 4500 struct vnode *vp; 4501 4502 mtx_lock(&sync_mtx); 4503 vp = mp->mnt_syncer; 4504 if (vp != NULL) 4505 mp->mnt_syncer = NULL; 4506 mtx_unlock(&sync_mtx); 4507 if (vp != NULL) 4508 vrele(vp); 4509 } 4510 4511 /* 4512 * Do a lazy sync of the filesystem. 4513 */ 4514 static int 4515 sync_fsync(struct vop_fsync_args *ap) 4516 { 4517 struct vnode *syncvp = ap->a_vp; 4518 struct mount *mp = syncvp->v_mount; 4519 int error, save; 4520 struct bufobj *bo; 4521 4522 /* 4523 * We only need to do something if this is a lazy evaluation. 4524 */ 4525 if (ap->a_waitfor != MNT_LAZY) 4526 return (0); 4527 4528 /* 4529 * Move ourselves to the back of the sync list. 4530 */ 4531 bo = &syncvp->v_bufobj; 4532 BO_LOCK(bo); 4533 vn_syncer_add_to_worklist(bo, syncdelay); 4534 BO_UNLOCK(bo); 4535 4536 /* 4537 * Walk the list of vnodes pushing all that are dirty and 4538 * not already on the sync list. 4539 */ 4540 if (vfs_busy(mp, MBF_NOWAIT) != 0) 4541 return (0); 4542 if (vn_start_write(NULL, &mp, V_NOWAIT) != 0) { 4543 vfs_unbusy(mp); 4544 return (0); 4545 } 4546 save = curthread_pflags_set(TDP_SYNCIO); 4547 vfs_msync(mp, MNT_NOWAIT); 4548 error = VFS_SYNC(mp, MNT_LAZY); 4549 curthread_pflags_restore(save); 4550 vn_finished_write(mp); 4551 vfs_unbusy(mp); 4552 return (error); 4553 } 4554 4555 /* 4556 * The syncer vnode is no referenced. 4557 */ 4558 static int 4559 sync_inactive(struct vop_inactive_args *ap) 4560 { 4561 4562 vgone(ap->a_vp); 4563 return (0); 4564 } 4565 4566 /* 4567 * The syncer vnode is no longer needed and is being decommissioned. 4568 * 4569 * Modifications to the worklist must be protected by sync_mtx. 4570 */ 4571 static int 4572 sync_reclaim(struct vop_reclaim_args *ap) 4573 { 4574 struct vnode *vp = ap->a_vp; 4575 struct bufobj *bo; 4576 4577 bo = &vp->v_bufobj; 4578 BO_LOCK(bo); 4579 mtx_lock(&sync_mtx); 4580 if (vp->v_mount->mnt_syncer == vp) 4581 vp->v_mount->mnt_syncer = NULL; 4582 if (bo->bo_flag & BO_ONWORKLST) { 4583 LIST_REMOVE(bo, bo_synclist); 4584 syncer_worklist_len--; 4585 sync_vnode_count--; 4586 bo->bo_flag &= ~BO_ONWORKLST; 4587 } 4588 mtx_unlock(&sync_mtx); 4589 BO_UNLOCK(bo); 4590 4591 return (0); 4592 } 4593 4594 int 4595 vn_need_pageq_flush(struct vnode *vp) 4596 { 4597 struct vm_object *obj; 4598 int need; 4599 4600 MPASS(mtx_owned(VI_MTX(vp))); 4601 need = 0; 4602 if ((obj = vp->v_object) != NULL && (vp->v_vflag & VV_NOSYNC) == 0 && 4603 (obj->flags & OBJ_MIGHTBEDIRTY) != 0) 4604 need = 1; 4605 return (need); 4606 } 4607 4608 /* 4609 * Check if vnode represents a disk device 4610 */ 4611 int 4612 vn_isdisk(struct vnode *vp, int *errp) 4613 { 4614 int error; 4615 4616 if (vp->v_type != VCHR) { 4617 error = ENOTBLK; 4618 goto out; 4619 } 4620 error = 0; 4621 dev_lock(); 4622 if (vp->v_rdev == NULL) 4623 error = ENXIO; 4624 else if (vp->v_rdev->si_devsw == NULL) 4625 error = ENXIO; 4626 else if (!(vp->v_rdev->si_devsw->d_flags & D_DISK)) 4627 error = ENOTBLK; 4628 dev_unlock(); 4629 out: 4630 if (errp != NULL) 4631 *errp = error; 4632 return (error == 0); 4633 } 4634 4635 /* 4636 * Common filesystem object access control check routine. Accepts a 4637 * vnode's type, "mode", uid and gid, requested access mode, credentials, 4638 * and optional call-by-reference privused argument allowing vaccess() 4639 * to indicate to the caller whether privilege was used to satisfy the 4640 * request (obsoleted). Returns 0 on success, or an errno on failure. 4641 */ 4642 int 4643 vaccess(enum vtype type, mode_t file_mode, uid_t file_uid, gid_t file_gid, 4644 accmode_t accmode, struct ucred *cred, int *privused) 4645 { 4646 accmode_t dac_granted; 4647 accmode_t priv_granted; 4648 4649 KASSERT((accmode & ~(VEXEC | VWRITE | VREAD | VADMIN | VAPPEND)) == 0, 4650 ("invalid bit in accmode")); 4651 KASSERT((accmode & VAPPEND) == 0 || (accmode & VWRITE), 4652 ("VAPPEND without VWRITE")); 4653 4654 /* 4655 * Look for a normal, non-privileged way to access the file/directory 4656 * as requested. If it exists, go with that. 4657 */ 4658 4659 if (privused != NULL) 4660 *privused = 0; 4661 4662 dac_granted = 0; 4663 4664 /* Check the owner. */ 4665 if (cred->cr_uid == file_uid) { 4666 dac_granted |= VADMIN; 4667 if (file_mode & S_IXUSR) 4668 dac_granted |= VEXEC; 4669 if (file_mode & S_IRUSR) 4670 dac_granted |= VREAD; 4671 if (file_mode & S_IWUSR) 4672 dac_granted |= (VWRITE | VAPPEND); 4673 4674 if ((accmode & dac_granted) == accmode) 4675 return (0); 4676 4677 goto privcheck; 4678 } 4679 4680 /* Otherwise, check the groups (first match) */ 4681 if (groupmember(file_gid, cred)) { 4682 if (file_mode & S_IXGRP) 4683 dac_granted |= VEXEC; 4684 if (file_mode & S_IRGRP) 4685 dac_granted |= VREAD; 4686 if (file_mode & S_IWGRP) 4687 dac_granted |= (VWRITE | VAPPEND); 4688 4689 if ((accmode & dac_granted) == accmode) 4690 return (0); 4691 4692 goto privcheck; 4693 } 4694 4695 /* Otherwise, check everyone else. */ 4696 if (file_mode & S_IXOTH) 4697 dac_granted |= VEXEC; 4698 if (file_mode & S_IROTH) 4699 dac_granted |= VREAD; 4700 if (file_mode & S_IWOTH) 4701 dac_granted |= (VWRITE | VAPPEND); 4702 if ((accmode & dac_granted) == accmode) 4703 return (0); 4704 4705 privcheck: 4706 /* 4707 * Build a privilege mask to determine if the set of privileges 4708 * satisfies the requirements when combined with the granted mask 4709 * from above. For each privilege, if the privilege is required, 4710 * bitwise or the request type onto the priv_granted mask. 4711 */ 4712 priv_granted = 0; 4713 4714 if (type == VDIR) { 4715 /* 4716 * For directories, use PRIV_VFS_LOOKUP to satisfy VEXEC 4717 * requests, instead of PRIV_VFS_EXEC. 4718 */ 4719 if ((accmode & VEXEC) && ((dac_granted & VEXEC) == 0) && 4720 !priv_check_cred(cred, PRIV_VFS_LOOKUP)) 4721 priv_granted |= VEXEC; 4722 } else { 4723 /* 4724 * Ensure that at least one execute bit is on. Otherwise, 4725 * a privileged user will always succeed, and we don't want 4726 * this to happen unless the file really is executable. 4727 */ 4728 if ((accmode & VEXEC) && ((dac_granted & VEXEC) == 0) && 4729 (file_mode & (S_IXUSR | S_IXGRP | S_IXOTH)) != 0 && 4730 !priv_check_cred(cred, PRIV_VFS_EXEC)) 4731 priv_granted |= VEXEC; 4732 } 4733 4734 if ((accmode & VREAD) && ((dac_granted & VREAD) == 0) && 4735 !priv_check_cred(cred, PRIV_VFS_READ)) 4736 priv_granted |= VREAD; 4737 4738 if ((accmode & VWRITE) && ((dac_granted & VWRITE) == 0) && 4739 !priv_check_cred(cred, PRIV_VFS_WRITE)) 4740 priv_granted |= (VWRITE | VAPPEND); 4741 4742 if ((accmode & VADMIN) && ((dac_granted & VADMIN) == 0) && 4743 !priv_check_cred(cred, PRIV_VFS_ADMIN)) 4744 priv_granted |= VADMIN; 4745 4746 if ((accmode & (priv_granted | dac_granted)) == accmode) { 4747 /* XXX audit: privilege used */ 4748 if (privused != NULL) 4749 *privused = 1; 4750 return (0); 4751 } 4752 4753 return ((accmode & VADMIN) ? EPERM : EACCES); 4754 } 4755 4756 /* 4757 * Credential check based on process requesting service, and per-attribute 4758 * permissions. 4759 */ 4760 int 4761 extattr_check_cred(struct vnode *vp, int attrnamespace, struct ucred *cred, 4762 struct thread *td, accmode_t accmode) 4763 { 4764 4765 /* 4766 * Kernel-invoked always succeeds. 4767 */ 4768 if (cred == NOCRED) 4769 return (0); 4770 4771 /* 4772 * Do not allow privileged processes in jail to directly manipulate 4773 * system attributes. 4774 */ 4775 switch (attrnamespace) { 4776 case EXTATTR_NAMESPACE_SYSTEM: 4777 /* Potentially should be: return (EPERM); */ 4778 return (priv_check_cred(cred, PRIV_VFS_EXTATTR_SYSTEM)); 4779 case EXTATTR_NAMESPACE_USER: 4780 return (VOP_ACCESS(vp, accmode, cred, td)); 4781 default: 4782 return (EPERM); 4783 } 4784 } 4785 4786 #ifdef DEBUG_VFS_LOCKS 4787 /* 4788 * This only exists to suppress warnings from unlocked specfs accesses. It is 4789 * no longer ok to have an unlocked VFS. 4790 */ 4791 #define IGNORE_LOCK(vp) (panicstr != NULL || (vp) == NULL || \ 4792 (vp)->v_type == VCHR || (vp)->v_type == VBAD) 4793 4794 int vfs_badlock_ddb = 1; /* Drop into debugger on violation. */ 4795 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_ddb, CTLFLAG_RW, &vfs_badlock_ddb, 0, 4796 "Drop into debugger on lock violation"); 4797 4798 int vfs_badlock_mutex = 1; /* Check for interlock across VOPs. */ 4799 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_mutex, CTLFLAG_RW, &vfs_badlock_mutex, 4800 0, "Check for interlock across VOPs"); 4801 4802 int vfs_badlock_print = 1; /* Print lock violations. */ 4803 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_print, CTLFLAG_RW, &vfs_badlock_print, 4804 0, "Print lock violations"); 4805 4806 int vfs_badlock_vnode = 1; /* Print vnode details on lock violations. */ 4807 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_vnode, CTLFLAG_RW, &vfs_badlock_vnode, 4808 0, "Print vnode details on lock violations"); 4809 4810 #ifdef KDB 4811 int vfs_badlock_backtrace = 1; /* Print backtrace at lock violations. */ 4812 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_backtrace, CTLFLAG_RW, 4813 &vfs_badlock_backtrace, 0, "Print backtrace at lock violations"); 4814 #endif 4815 4816 static void 4817 vfs_badlock(const char *msg, const char *str, struct vnode *vp) 4818 { 4819 4820 #ifdef KDB 4821 if (vfs_badlock_backtrace) 4822 kdb_backtrace(); 4823 #endif 4824 if (vfs_badlock_vnode) 4825 vn_printf(vp, "vnode "); 4826 if (vfs_badlock_print) 4827 printf("%s: %p %s\n", str, (void *)vp, msg); 4828 if (vfs_badlock_ddb) 4829 kdb_enter(KDB_WHY_VFSLOCK, "lock violation"); 4830 } 4831 4832 void 4833 assert_vi_locked(struct vnode *vp, const char *str) 4834 { 4835 4836 if (vfs_badlock_mutex && !mtx_owned(VI_MTX(vp))) 4837 vfs_badlock("interlock is not locked but should be", str, vp); 4838 } 4839 4840 void 4841 assert_vi_unlocked(struct vnode *vp, const char *str) 4842 { 4843 4844 if (vfs_badlock_mutex && mtx_owned(VI_MTX(vp))) 4845 vfs_badlock("interlock is locked but should not be", str, vp); 4846 } 4847 4848 void 4849 assert_vop_locked(struct vnode *vp, const char *str) 4850 { 4851 int locked; 4852 4853 if (!IGNORE_LOCK(vp)) { 4854 locked = VOP_ISLOCKED(vp); 4855 if (locked == 0 || locked == LK_EXCLOTHER) 4856 vfs_badlock("is not locked but should be", str, vp); 4857 } 4858 } 4859 4860 void 4861 assert_vop_unlocked(struct vnode *vp, const char *str) 4862 { 4863 4864 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) == LK_EXCLUSIVE) 4865 vfs_badlock("is locked but should not be", str, vp); 4866 } 4867 4868 void 4869 assert_vop_elocked(struct vnode *vp, const char *str) 4870 { 4871 4872 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) != LK_EXCLUSIVE) 4873 vfs_badlock("is not exclusive locked but should be", str, vp); 4874 } 4875 #endif /* DEBUG_VFS_LOCKS */ 4876 4877 void 4878 vop_rename_fail(struct vop_rename_args *ap) 4879 { 4880 4881 if (ap->a_tvp != NULL) 4882 vput(ap->a_tvp); 4883 if (ap->a_tdvp == ap->a_tvp) 4884 vrele(ap->a_tdvp); 4885 else 4886 vput(ap->a_tdvp); 4887 vrele(ap->a_fdvp); 4888 vrele(ap->a_fvp); 4889 } 4890 4891 void 4892 vop_rename_pre(void *ap) 4893 { 4894 struct vop_rename_args *a = ap; 4895 4896 #ifdef DEBUG_VFS_LOCKS 4897 if (a->a_tvp) 4898 ASSERT_VI_UNLOCKED(a->a_tvp, "VOP_RENAME"); 4899 ASSERT_VI_UNLOCKED(a->a_tdvp, "VOP_RENAME"); 4900 ASSERT_VI_UNLOCKED(a->a_fvp, "VOP_RENAME"); 4901 ASSERT_VI_UNLOCKED(a->a_fdvp, "VOP_RENAME"); 4902 4903 /* Check the source (from). */ 4904 if (a->a_tdvp->v_vnlock != a->a_fdvp->v_vnlock && 4905 (a->a_tvp == NULL || a->a_tvp->v_vnlock != a->a_fdvp->v_vnlock)) 4906 ASSERT_VOP_UNLOCKED(a->a_fdvp, "vop_rename: fdvp locked"); 4907 if (a->a_tvp == NULL || a->a_tvp->v_vnlock != a->a_fvp->v_vnlock) 4908 ASSERT_VOP_UNLOCKED(a->a_fvp, "vop_rename: fvp locked"); 4909 4910 /* Check the target. */ 4911 if (a->a_tvp) 4912 ASSERT_VOP_LOCKED(a->a_tvp, "vop_rename: tvp not locked"); 4913 ASSERT_VOP_LOCKED(a->a_tdvp, "vop_rename: tdvp not locked"); 4914 #endif 4915 if (a->a_tdvp != a->a_fdvp) 4916 vhold(a->a_fdvp); 4917 if (a->a_tvp != a->a_fvp) 4918 vhold(a->a_fvp); 4919 vhold(a->a_tdvp); 4920 if (a->a_tvp) 4921 vhold(a->a_tvp); 4922 } 4923 4924 #ifdef DEBUG_VFS_LOCKS 4925 void 4926 vop_strategy_pre(void *ap) 4927 { 4928 struct vop_strategy_args *a; 4929 struct buf *bp; 4930 4931 a = ap; 4932 bp = a->a_bp; 4933 4934 /* 4935 * Cluster ops lock their component buffers but not the IO container. 4936 */ 4937 if ((bp->b_flags & B_CLUSTER) != 0) 4938 return; 4939 4940 if (panicstr == NULL && !BUF_ISLOCKED(bp)) { 4941 if (vfs_badlock_print) 4942 printf( 4943 "VOP_STRATEGY: bp is not locked but should be\n"); 4944 if (vfs_badlock_ddb) 4945 kdb_enter(KDB_WHY_VFSLOCK, "lock violation"); 4946 } 4947 } 4948 4949 void 4950 vop_lock_pre(void *ap) 4951 { 4952 struct vop_lock1_args *a = ap; 4953 4954 if ((a->a_flags & LK_INTERLOCK) == 0) 4955 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_LOCK"); 4956 else 4957 ASSERT_VI_LOCKED(a->a_vp, "VOP_LOCK"); 4958 } 4959 4960 void 4961 vop_lock_post(void *ap, int rc) 4962 { 4963 struct vop_lock1_args *a = ap; 4964 4965 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_LOCK"); 4966 if (rc == 0 && (a->a_flags & LK_EXCLOTHER) == 0) 4967 ASSERT_VOP_LOCKED(a->a_vp, "VOP_LOCK"); 4968 } 4969 4970 void 4971 vop_unlock_pre(void *ap) 4972 { 4973 struct vop_unlock_args *a = ap; 4974 4975 if (a->a_flags & LK_INTERLOCK) 4976 ASSERT_VI_LOCKED(a->a_vp, "VOP_UNLOCK"); 4977 ASSERT_VOP_LOCKED(a->a_vp, "VOP_UNLOCK"); 4978 } 4979 4980 void 4981 vop_unlock_post(void *ap, int rc) 4982 { 4983 struct vop_unlock_args *a = ap; 4984 4985 if (a->a_flags & LK_INTERLOCK) 4986 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_UNLOCK"); 4987 } 4988 4989 void 4990 vop_need_inactive_pre(void *ap) 4991 { 4992 struct vop_need_inactive_args *a = ap; 4993 4994 ASSERT_VI_LOCKED(a->a_vp, "VOP_NEED_INACTIVE"); 4995 } 4996 4997 void 4998 vop_need_inactive_post(void *ap, int rc) 4999 { 5000 struct vop_need_inactive_args *a = ap; 5001 5002 ASSERT_VI_LOCKED(a->a_vp, "VOP_NEED_INACTIVE"); 5003 } 5004 #endif 5005 5006 void 5007 vop_create_post(void *ap, int rc) 5008 { 5009 struct vop_create_args *a = ap; 5010 5011 if (!rc) 5012 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 5013 } 5014 5015 void 5016 vop_deleteextattr_post(void *ap, int rc) 5017 { 5018 struct vop_deleteextattr_args *a = ap; 5019 5020 if (!rc) 5021 VFS_KNOTE_LOCKED(a->a_vp, NOTE_ATTRIB); 5022 } 5023 5024 void 5025 vop_link_post(void *ap, int rc) 5026 { 5027 struct vop_link_args *a = ap; 5028 5029 if (!rc) { 5030 VFS_KNOTE_LOCKED(a->a_vp, NOTE_LINK); 5031 VFS_KNOTE_LOCKED(a->a_tdvp, NOTE_WRITE); 5032 } 5033 } 5034 5035 void 5036 vop_mkdir_post(void *ap, int rc) 5037 { 5038 struct vop_mkdir_args *a = ap; 5039 5040 if (!rc) 5041 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE | NOTE_LINK); 5042 } 5043 5044 void 5045 vop_mknod_post(void *ap, int rc) 5046 { 5047 struct vop_mknod_args *a = ap; 5048 5049 if (!rc) 5050 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 5051 } 5052 5053 void 5054 vop_reclaim_post(void *ap, int rc) 5055 { 5056 struct vop_reclaim_args *a = ap; 5057 5058 if (!rc) 5059 VFS_KNOTE_LOCKED(a->a_vp, NOTE_REVOKE); 5060 } 5061 5062 void 5063 vop_remove_post(void *ap, int rc) 5064 { 5065 struct vop_remove_args *a = ap; 5066 5067 if (!rc) { 5068 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 5069 VFS_KNOTE_LOCKED(a->a_vp, NOTE_DELETE); 5070 } 5071 } 5072 5073 void 5074 vop_rename_post(void *ap, int rc) 5075 { 5076 struct vop_rename_args *a = ap; 5077 long hint; 5078 5079 if (!rc) { 5080 hint = NOTE_WRITE; 5081 if (a->a_fdvp == a->a_tdvp) { 5082 if (a->a_tvp != NULL && a->a_tvp->v_type == VDIR) 5083 hint |= NOTE_LINK; 5084 VFS_KNOTE_UNLOCKED(a->a_fdvp, hint); 5085 VFS_KNOTE_UNLOCKED(a->a_tdvp, hint); 5086 } else { 5087 hint |= NOTE_EXTEND; 5088 if (a->a_fvp->v_type == VDIR) 5089 hint |= NOTE_LINK; 5090 VFS_KNOTE_UNLOCKED(a->a_fdvp, hint); 5091 5092 if (a->a_fvp->v_type == VDIR && a->a_tvp != NULL && 5093 a->a_tvp->v_type == VDIR) 5094 hint &= ~NOTE_LINK; 5095 VFS_KNOTE_UNLOCKED(a->a_tdvp, hint); 5096 } 5097 5098 VFS_KNOTE_UNLOCKED(a->a_fvp, NOTE_RENAME); 5099 if (a->a_tvp) 5100 VFS_KNOTE_UNLOCKED(a->a_tvp, NOTE_DELETE); 5101 } 5102 if (a->a_tdvp != a->a_fdvp) 5103 vdrop(a->a_fdvp); 5104 if (a->a_tvp != a->a_fvp) 5105 vdrop(a->a_fvp); 5106 vdrop(a->a_tdvp); 5107 if (a->a_tvp) 5108 vdrop(a->a_tvp); 5109 } 5110 5111 void 5112 vop_rmdir_post(void *ap, int rc) 5113 { 5114 struct vop_rmdir_args *a = ap; 5115 5116 if (!rc) { 5117 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE | NOTE_LINK); 5118 VFS_KNOTE_LOCKED(a->a_vp, NOTE_DELETE); 5119 } 5120 } 5121 5122 void 5123 vop_setattr_post(void *ap, int rc) 5124 { 5125 struct vop_setattr_args *a = ap; 5126 5127 if (!rc) 5128 VFS_KNOTE_LOCKED(a->a_vp, NOTE_ATTRIB); 5129 } 5130 5131 void 5132 vop_setextattr_post(void *ap, int rc) 5133 { 5134 struct vop_setextattr_args *a = ap; 5135 5136 if (!rc) 5137 VFS_KNOTE_LOCKED(a->a_vp, NOTE_ATTRIB); 5138 } 5139 5140 void 5141 vop_symlink_post(void *ap, int rc) 5142 { 5143 struct vop_symlink_args *a = ap; 5144 5145 if (!rc) 5146 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 5147 } 5148 5149 void 5150 vop_open_post(void *ap, int rc) 5151 { 5152 struct vop_open_args *a = ap; 5153 5154 if (!rc) 5155 VFS_KNOTE_LOCKED(a->a_vp, NOTE_OPEN); 5156 } 5157 5158 void 5159 vop_close_post(void *ap, int rc) 5160 { 5161 struct vop_close_args *a = ap; 5162 5163 if (!rc && (a->a_cred != NOCRED || /* filter out revokes */ 5164 (a->a_vp->v_iflag & VI_DOOMED) == 0)) { 5165 VFS_KNOTE_LOCKED(a->a_vp, (a->a_fflag & FWRITE) != 0 ? 5166 NOTE_CLOSE_WRITE : NOTE_CLOSE); 5167 } 5168 } 5169 5170 void 5171 vop_read_post(void *ap, int rc) 5172 { 5173 struct vop_read_args *a = ap; 5174 5175 if (!rc) 5176 VFS_KNOTE_LOCKED(a->a_vp, NOTE_READ); 5177 } 5178 5179 void 5180 vop_readdir_post(void *ap, int rc) 5181 { 5182 struct vop_readdir_args *a = ap; 5183 5184 if (!rc) 5185 VFS_KNOTE_LOCKED(a->a_vp, NOTE_READ); 5186 } 5187 5188 static struct knlist fs_knlist; 5189 5190 static void 5191 vfs_event_init(void *arg) 5192 { 5193 knlist_init_mtx(&fs_knlist, NULL); 5194 } 5195 /* XXX - correct order? */ 5196 SYSINIT(vfs_knlist, SI_SUB_VFS, SI_ORDER_ANY, vfs_event_init, NULL); 5197 5198 void 5199 vfs_event_signal(fsid_t *fsid, uint32_t event, intptr_t data __unused) 5200 { 5201 5202 KNOTE_UNLOCKED(&fs_knlist, event); 5203 } 5204 5205 static int filt_fsattach(struct knote *kn); 5206 static void filt_fsdetach(struct knote *kn); 5207 static int filt_fsevent(struct knote *kn, long hint); 5208 5209 struct filterops fs_filtops = { 5210 .f_isfd = 0, 5211 .f_attach = filt_fsattach, 5212 .f_detach = filt_fsdetach, 5213 .f_event = filt_fsevent 5214 }; 5215 5216 static int 5217 filt_fsattach(struct knote *kn) 5218 { 5219 5220 kn->kn_flags |= EV_CLEAR; 5221 knlist_add(&fs_knlist, kn, 0); 5222 return (0); 5223 } 5224 5225 static void 5226 filt_fsdetach(struct knote *kn) 5227 { 5228 5229 knlist_remove(&fs_knlist, kn, 0); 5230 } 5231 5232 static int 5233 filt_fsevent(struct knote *kn, long hint) 5234 { 5235 5236 kn->kn_fflags |= hint; 5237 return (kn->kn_fflags != 0); 5238 } 5239 5240 static int 5241 sysctl_vfs_ctl(SYSCTL_HANDLER_ARGS) 5242 { 5243 struct vfsidctl vc; 5244 int error; 5245 struct mount *mp; 5246 5247 error = SYSCTL_IN(req, &vc, sizeof(vc)); 5248 if (error) 5249 return (error); 5250 if (vc.vc_vers != VFS_CTL_VERS1) 5251 return (EINVAL); 5252 mp = vfs_getvfs(&vc.vc_fsid); 5253 if (mp == NULL) 5254 return (ENOENT); 5255 /* ensure that a specific sysctl goes to the right filesystem. */ 5256 if (strcmp(vc.vc_fstypename, "*") != 0 && 5257 strcmp(vc.vc_fstypename, mp->mnt_vfc->vfc_name) != 0) { 5258 vfs_rel(mp); 5259 return (EINVAL); 5260 } 5261 VCTLTOREQ(&vc, req); 5262 error = VFS_SYSCTL(mp, vc.vc_op, req); 5263 vfs_rel(mp); 5264 return (error); 5265 } 5266 5267 SYSCTL_PROC(_vfs, OID_AUTO, ctl, CTLTYPE_OPAQUE | CTLFLAG_WR, 5268 NULL, 0, sysctl_vfs_ctl, "", 5269 "Sysctl by fsid"); 5270 5271 /* 5272 * Function to initialize a va_filerev field sensibly. 5273 * XXX: Wouldn't a random number make a lot more sense ?? 5274 */ 5275 u_quad_t 5276 init_va_filerev(void) 5277 { 5278 struct bintime bt; 5279 5280 getbinuptime(&bt); 5281 return (((u_quad_t)bt.sec << 32LL) | (bt.frac >> 32LL)); 5282 } 5283 5284 static int filt_vfsread(struct knote *kn, long hint); 5285 static int filt_vfswrite(struct knote *kn, long hint); 5286 static int filt_vfsvnode(struct knote *kn, long hint); 5287 static void filt_vfsdetach(struct knote *kn); 5288 static struct filterops vfsread_filtops = { 5289 .f_isfd = 1, 5290 .f_detach = filt_vfsdetach, 5291 .f_event = filt_vfsread 5292 }; 5293 static struct filterops vfswrite_filtops = { 5294 .f_isfd = 1, 5295 .f_detach = filt_vfsdetach, 5296 .f_event = filt_vfswrite 5297 }; 5298 static struct filterops vfsvnode_filtops = { 5299 .f_isfd = 1, 5300 .f_detach = filt_vfsdetach, 5301 .f_event = filt_vfsvnode 5302 }; 5303 5304 static void 5305 vfs_knllock(void *arg) 5306 { 5307 struct vnode *vp = arg; 5308 5309 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 5310 } 5311 5312 static void 5313 vfs_knlunlock(void *arg) 5314 { 5315 struct vnode *vp = arg; 5316 5317 VOP_UNLOCK(vp, 0); 5318 } 5319 5320 static void 5321 vfs_knl_assert_locked(void *arg) 5322 { 5323 #ifdef DEBUG_VFS_LOCKS 5324 struct vnode *vp = arg; 5325 5326 ASSERT_VOP_LOCKED(vp, "vfs_knl_assert_locked"); 5327 #endif 5328 } 5329 5330 static void 5331 vfs_knl_assert_unlocked(void *arg) 5332 { 5333 #ifdef DEBUG_VFS_LOCKS 5334 struct vnode *vp = arg; 5335 5336 ASSERT_VOP_UNLOCKED(vp, "vfs_knl_assert_unlocked"); 5337 #endif 5338 } 5339 5340 int 5341 vfs_kqfilter(struct vop_kqfilter_args *ap) 5342 { 5343 struct vnode *vp = ap->a_vp; 5344 struct knote *kn = ap->a_kn; 5345 struct knlist *knl; 5346 5347 switch (kn->kn_filter) { 5348 case EVFILT_READ: 5349 kn->kn_fop = &vfsread_filtops; 5350 break; 5351 case EVFILT_WRITE: 5352 kn->kn_fop = &vfswrite_filtops; 5353 break; 5354 case EVFILT_VNODE: 5355 kn->kn_fop = &vfsvnode_filtops; 5356 break; 5357 default: 5358 return (EINVAL); 5359 } 5360 5361 kn->kn_hook = (caddr_t)vp; 5362 5363 v_addpollinfo(vp); 5364 if (vp->v_pollinfo == NULL) 5365 return (ENOMEM); 5366 knl = &vp->v_pollinfo->vpi_selinfo.si_note; 5367 vhold(vp); 5368 knlist_add(knl, kn, 0); 5369 5370 return (0); 5371 } 5372 5373 /* 5374 * Detach knote from vnode 5375 */ 5376 static void 5377 filt_vfsdetach(struct knote *kn) 5378 { 5379 struct vnode *vp = (struct vnode *)kn->kn_hook; 5380 5381 KASSERT(vp->v_pollinfo != NULL, ("Missing v_pollinfo")); 5382 knlist_remove(&vp->v_pollinfo->vpi_selinfo.si_note, kn, 0); 5383 vdrop(vp); 5384 } 5385 5386 /*ARGSUSED*/ 5387 static int 5388 filt_vfsread(struct knote *kn, long hint) 5389 { 5390 struct vnode *vp = (struct vnode *)kn->kn_hook; 5391 struct vattr va; 5392 int res; 5393 5394 /* 5395 * filesystem is gone, so set the EOF flag and schedule 5396 * the knote for deletion. 5397 */ 5398 if (hint == NOTE_REVOKE || (hint == 0 && vp->v_type == VBAD)) { 5399 VI_LOCK(vp); 5400 kn->kn_flags |= (EV_EOF | EV_ONESHOT); 5401 VI_UNLOCK(vp); 5402 return (1); 5403 } 5404 5405 if (VOP_GETATTR(vp, &va, curthread->td_ucred)) 5406 return (0); 5407 5408 VI_LOCK(vp); 5409 kn->kn_data = va.va_size - kn->kn_fp->f_offset; 5410 res = (kn->kn_sfflags & NOTE_FILE_POLL) != 0 || kn->kn_data != 0; 5411 VI_UNLOCK(vp); 5412 return (res); 5413 } 5414 5415 /*ARGSUSED*/ 5416 static int 5417 filt_vfswrite(struct knote *kn, long hint) 5418 { 5419 struct vnode *vp = (struct vnode *)kn->kn_hook; 5420 5421 VI_LOCK(vp); 5422 5423 /* 5424 * filesystem is gone, so set the EOF flag and schedule 5425 * the knote for deletion. 5426 */ 5427 if (hint == NOTE_REVOKE || (hint == 0 && vp->v_type == VBAD)) 5428 kn->kn_flags |= (EV_EOF | EV_ONESHOT); 5429 5430 kn->kn_data = 0; 5431 VI_UNLOCK(vp); 5432 return (1); 5433 } 5434 5435 static int 5436 filt_vfsvnode(struct knote *kn, long hint) 5437 { 5438 struct vnode *vp = (struct vnode *)kn->kn_hook; 5439 int res; 5440 5441 VI_LOCK(vp); 5442 if (kn->kn_sfflags & hint) 5443 kn->kn_fflags |= hint; 5444 if (hint == NOTE_REVOKE || (hint == 0 && vp->v_type == VBAD)) { 5445 kn->kn_flags |= EV_EOF; 5446 VI_UNLOCK(vp); 5447 return (1); 5448 } 5449 res = (kn->kn_fflags != 0); 5450 VI_UNLOCK(vp); 5451 return (res); 5452 } 5453 5454 int 5455 vfs_read_dirent(struct vop_readdir_args *ap, struct dirent *dp, off_t off) 5456 { 5457 int error; 5458 5459 if (dp->d_reclen > ap->a_uio->uio_resid) 5460 return (ENAMETOOLONG); 5461 error = uiomove(dp, dp->d_reclen, ap->a_uio); 5462 if (error) { 5463 if (ap->a_ncookies != NULL) { 5464 if (ap->a_cookies != NULL) 5465 free(ap->a_cookies, M_TEMP); 5466 ap->a_cookies = NULL; 5467 *ap->a_ncookies = 0; 5468 } 5469 return (error); 5470 } 5471 if (ap->a_ncookies == NULL) 5472 return (0); 5473 5474 KASSERT(ap->a_cookies, 5475 ("NULL ap->a_cookies value with non-NULL ap->a_ncookies!")); 5476 5477 *ap->a_cookies = realloc(*ap->a_cookies, 5478 (*ap->a_ncookies + 1) * sizeof(u_long), M_TEMP, M_WAITOK | M_ZERO); 5479 (*ap->a_cookies)[*ap->a_ncookies] = off; 5480 *ap->a_ncookies += 1; 5481 return (0); 5482 } 5483 5484 /* 5485 * Mark for update the access time of the file if the filesystem 5486 * supports VOP_MARKATIME. This functionality is used by execve and 5487 * mmap, so we want to avoid the I/O implied by directly setting 5488 * va_atime for the sake of efficiency. 5489 */ 5490 void 5491 vfs_mark_atime(struct vnode *vp, struct ucred *cred) 5492 { 5493 struct mount *mp; 5494 5495 mp = vp->v_mount; 5496 ASSERT_VOP_LOCKED(vp, "vfs_mark_atime"); 5497 if (mp != NULL && (mp->mnt_flag & (MNT_NOATIME | MNT_RDONLY)) == 0) 5498 (void)VOP_MARKATIME(vp); 5499 } 5500 5501 /* 5502 * The purpose of this routine is to remove granularity from accmode_t, 5503 * reducing it into standard unix access bits - VEXEC, VREAD, VWRITE, 5504 * VADMIN and VAPPEND. 5505 * 5506 * If it returns 0, the caller is supposed to continue with the usual 5507 * access checks using 'accmode' as modified by this routine. If it 5508 * returns nonzero value, the caller is supposed to return that value 5509 * as errno. 5510 * 5511 * Note that after this routine runs, accmode may be zero. 5512 */ 5513 int 5514 vfs_unixify_accmode(accmode_t *accmode) 5515 { 5516 /* 5517 * There is no way to specify explicit "deny" rule using 5518 * file mode or POSIX.1e ACLs. 5519 */ 5520 if (*accmode & VEXPLICIT_DENY) { 5521 *accmode = 0; 5522 return (0); 5523 } 5524 5525 /* 5526 * None of these can be translated into usual access bits. 5527 * Also, the common case for NFSv4 ACLs is to not contain 5528 * either of these bits. Caller should check for VWRITE 5529 * on the containing directory instead. 5530 */ 5531 if (*accmode & (VDELETE_CHILD | VDELETE)) 5532 return (EPERM); 5533 5534 if (*accmode & VADMIN_PERMS) { 5535 *accmode &= ~VADMIN_PERMS; 5536 *accmode |= VADMIN; 5537 } 5538 5539 /* 5540 * There is no way to deny VREAD_ATTRIBUTES, VREAD_ACL 5541 * or VSYNCHRONIZE using file mode or POSIX.1e ACL. 5542 */ 5543 *accmode &= ~(VSTAT_PERMS | VSYNCHRONIZE); 5544 5545 return (0); 5546 } 5547 5548 /* 5549 * These are helper functions for filesystems to traverse all 5550 * their vnodes. See MNT_VNODE_FOREACH_ALL() in sys/mount.h. 5551 * 5552 * This interface replaces MNT_VNODE_FOREACH. 5553 */ 5554 5555 MALLOC_DEFINE(M_VNODE_MARKER, "vnodemarker", "vnode marker"); 5556 5557 struct vnode * 5558 __mnt_vnode_next_all(struct vnode **mvp, struct mount *mp) 5559 { 5560 struct vnode *vp; 5561 5562 if (should_yield()) 5563 kern_yield(PRI_USER); 5564 MNT_ILOCK(mp); 5565 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch")); 5566 for (vp = TAILQ_NEXT(*mvp, v_nmntvnodes); vp != NULL; 5567 vp = TAILQ_NEXT(vp, v_nmntvnodes)) { 5568 /* Allow a racy peek at VI_DOOMED to save a lock acquisition. */ 5569 if (vp->v_type == VMARKER || (vp->v_iflag & VI_DOOMED) != 0) 5570 continue; 5571 VI_LOCK(vp); 5572 if ((vp->v_iflag & VI_DOOMED) != 0) { 5573 VI_UNLOCK(vp); 5574 continue; 5575 } 5576 break; 5577 } 5578 if (vp == NULL) { 5579 __mnt_vnode_markerfree_all(mvp, mp); 5580 /* MNT_IUNLOCK(mp); -- done in above function */ 5581 mtx_assert(MNT_MTX(mp), MA_NOTOWNED); 5582 return (NULL); 5583 } 5584 TAILQ_REMOVE(&mp->mnt_nvnodelist, *mvp, v_nmntvnodes); 5585 TAILQ_INSERT_AFTER(&mp->mnt_nvnodelist, vp, *mvp, v_nmntvnodes); 5586 MNT_IUNLOCK(mp); 5587 return (vp); 5588 } 5589 5590 struct vnode * 5591 __mnt_vnode_first_all(struct vnode **mvp, struct mount *mp) 5592 { 5593 struct vnode *vp; 5594 5595 *mvp = malloc(sizeof(struct vnode), M_VNODE_MARKER, M_WAITOK | M_ZERO); 5596 MNT_ILOCK(mp); 5597 MNT_REF(mp); 5598 (*mvp)->v_mount = mp; 5599 (*mvp)->v_type = VMARKER; 5600 5601 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) { 5602 /* Allow a racy peek at VI_DOOMED to save a lock acquisition. */ 5603 if (vp->v_type == VMARKER || (vp->v_iflag & VI_DOOMED) != 0) 5604 continue; 5605 VI_LOCK(vp); 5606 if ((vp->v_iflag & VI_DOOMED) != 0) { 5607 VI_UNLOCK(vp); 5608 continue; 5609 } 5610 break; 5611 } 5612 if (vp == NULL) { 5613 MNT_REL(mp); 5614 MNT_IUNLOCK(mp); 5615 free(*mvp, M_VNODE_MARKER); 5616 *mvp = NULL; 5617 return (NULL); 5618 } 5619 TAILQ_INSERT_AFTER(&mp->mnt_nvnodelist, vp, *mvp, v_nmntvnodes); 5620 MNT_IUNLOCK(mp); 5621 return (vp); 5622 } 5623 5624 void 5625 __mnt_vnode_markerfree_all(struct vnode **mvp, struct mount *mp) 5626 { 5627 5628 if (*mvp == NULL) { 5629 MNT_IUNLOCK(mp); 5630 return; 5631 } 5632 5633 mtx_assert(MNT_MTX(mp), MA_OWNED); 5634 5635 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch")); 5636 TAILQ_REMOVE(&mp->mnt_nvnodelist, *mvp, v_nmntvnodes); 5637 MNT_REL(mp); 5638 MNT_IUNLOCK(mp); 5639 free(*mvp, M_VNODE_MARKER); 5640 *mvp = NULL; 5641 } 5642 5643 /* 5644 * These are helper functions for filesystems to traverse their 5645 * active vnodes. See MNT_VNODE_FOREACH_ACTIVE() in sys/mount.h 5646 */ 5647 static void 5648 mnt_vnode_markerfree_active(struct vnode **mvp, struct mount *mp) 5649 { 5650 5651 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch")); 5652 5653 MNT_ILOCK(mp); 5654 MNT_REL(mp); 5655 MNT_IUNLOCK(mp); 5656 free(*mvp, M_VNODE_MARKER); 5657 *mvp = NULL; 5658 } 5659 5660 /* 5661 * Relock the mp mount vnode list lock with the vp vnode interlock in the 5662 * conventional lock order during mnt_vnode_next_active iteration. 5663 * 5664 * On entry, the mount vnode list lock is held and the vnode interlock is not. 5665 * The list lock is dropped and reacquired. On success, both locks are held. 5666 * On failure, the mount vnode list lock is held but the vnode interlock is 5667 * not, and the procedure may have yielded. 5668 */ 5669 static bool 5670 mnt_vnode_next_active_relock(struct vnode *mvp, struct mount *mp, 5671 struct vnode *vp) 5672 { 5673 const struct vnode *tmp; 5674 bool held, ret; 5675 5676 VNASSERT(mvp->v_mount == mp && mvp->v_type == VMARKER && 5677 TAILQ_NEXT(mvp, v_actfreelist) != NULL, mvp, 5678 ("%s: bad marker", __func__)); 5679 VNASSERT(vp->v_mount == mp && vp->v_type != VMARKER, vp, 5680 ("%s: inappropriate vnode", __func__)); 5681 ASSERT_VI_UNLOCKED(vp, __func__); 5682 mtx_assert(&mp->mnt_listmtx, MA_OWNED); 5683 5684 ret = false; 5685 5686 TAILQ_REMOVE(&mp->mnt_activevnodelist, mvp, v_actfreelist); 5687 TAILQ_INSERT_BEFORE(vp, mvp, v_actfreelist); 5688 5689 /* 5690 * Use a hold to prevent vp from disappearing while the mount vnode 5691 * list lock is dropped and reacquired. Normally a hold would be 5692 * acquired with vhold(), but that might try to acquire the vnode 5693 * interlock, which would be a LOR with the mount vnode list lock. 5694 */ 5695 held = refcount_acquire_if_not_zero(&vp->v_holdcnt); 5696 mtx_unlock(&mp->mnt_listmtx); 5697 if (!held) 5698 goto abort; 5699 VI_LOCK(vp); 5700 if (!refcount_release_if_not_last(&vp->v_holdcnt)) { 5701 vdropl(vp); 5702 goto abort; 5703 } 5704 mtx_lock(&mp->mnt_listmtx); 5705 5706 /* 5707 * Determine whether the vnode is still the next one after the marker, 5708 * excepting any other markers. If the vnode has not been doomed by 5709 * vgone() then the hold should have ensured that it remained on the 5710 * active list. If it has been doomed but is still on the active list, 5711 * don't abort, but rather skip over it (avoid spinning on doomed 5712 * vnodes). 5713 */ 5714 tmp = mvp; 5715 do { 5716 tmp = TAILQ_NEXT(tmp, v_actfreelist); 5717 } while (tmp != NULL && tmp->v_type == VMARKER); 5718 if (tmp != vp) { 5719 mtx_unlock(&mp->mnt_listmtx); 5720 VI_UNLOCK(vp); 5721 goto abort; 5722 } 5723 5724 ret = true; 5725 goto out; 5726 abort: 5727 maybe_yield(); 5728 mtx_lock(&mp->mnt_listmtx); 5729 out: 5730 if (ret) 5731 ASSERT_VI_LOCKED(vp, __func__); 5732 else 5733 ASSERT_VI_UNLOCKED(vp, __func__); 5734 mtx_assert(&mp->mnt_listmtx, MA_OWNED); 5735 return (ret); 5736 } 5737 5738 static struct vnode * 5739 mnt_vnode_next_active(struct vnode **mvp, struct mount *mp) 5740 { 5741 struct vnode *vp, *nvp; 5742 5743 mtx_assert(&mp->mnt_listmtx, MA_OWNED); 5744 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch")); 5745 restart: 5746 vp = TAILQ_NEXT(*mvp, v_actfreelist); 5747 while (vp != NULL) { 5748 if (vp->v_type == VMARKER) { 5749 vp = TAILQ_NEXT(vp, v_actfreelist); 5750 continue; 5751 } 5752 /* 5753 * Try-lock because this is the wrong lock order. If that does 5754 * not succeed, drop the mount vnode list lock and try to 5755 * reacquire it and the vnode interlock in the right order. 5756 */ 5757 if (!VI_TRYLOCK(vp) && 5758 !mnt_vnode_next_active_relock(*mvp, mp, vp)) 5759 goto restart; 5760 KASSERT(vp->v_type != VMARKER, ("locked marker %p", vp)); 5761 KASSERT(vp->v_mount == mp || vp->v_mount == NULL, 5762 ("alien vnode on the active list %p %p", vp, mp)); 5763 if (vp->v_mount == mp && (vp->v_iflag & VI_DOOMED) == 0) 5764 break; 5765 nvp = TAILQ_NEXT(vp, v_actfreelist); 5766 VI_UNLOCK(vp); 5767 vp = nvp; 5768 } 5769 TAILQ_REMOVE(&mp->mnt_activevnodelist, *mvp, v_actfreelist); 5770 5771 /* Check if we are done */ 5772 if (vp == NULL) { 5773 mtx_unlock(&mp->mnt_listmtx); 5774 mnt_vnode_markerfree_active(mvp, mp); 5775 return (NULL); 5776 } 5777 TAILQ_INSERT_AFTER(&mp->mnt_activevnodelist, vp, *mvp, v_actfreelist); 5778 mtx_unlock(&mp->mnt_listmtx); 5779 ASSERT_VI_LOCKED(vp, "active iter"); 5780 KASSERT((vp->v_iflag & VI_ACTIVE) != 0, ("Non-active vp %p", vp)); 5781 return (vp); 5782 } 5783 5784 struct vnode * 5785 __mnt_vnode_next_active(struct vnode **mvp, struct mount *mp) 5786 { 5787 5788 if (should_yield()) 5789 kern_yield(PRI_USER); 5790 mtx_lock(&mp->mnt_listmtx); 5791 return (mnt_vnode_next_active(mvp, mp)); 5792 } 5793 5794 struct vnode * 5795 __mnt_vnode_first_active(struct vnode **mvp, struct mount *mp) 5796 { 5797 struct vnode *vp; 5798 5799 *mvp = malloc(sizeof(struct vnode), M_VNODE_MARKER, M_WAITOK | M_ZERO); 5800 MNT_ILOCK(mp); 5801 MNT_REF(mp); 5802 MNT_IUNLOCK(mp); 5803 (*mvp)->v_type = VMARKER; 5804 (*mvp)->v_mount = mp; 5805 5806 mtx_lock(&mp->mnt_listmtx); 5807 vp = TAILQ_FIRST(&mp->mnt_activevnodelist); 5808 if (vp == NULL) { 5809 mtx_unlock(&mp->mnt_listmtx); 5810 mnt_vnode_markerfree_active(mvp, mp); 5811 return (NULL); 5812 } 5813 TAILQ_INSERT_BEFORE(vp, *mvp, v_actfreelist); 5814 return (mnt_vnode_next_active(mvp, mp)); 5815 } 5816 5817 void 5818 __mnt_vnode_markerfree_active(struct vnode **mvp, struct mount *mp) 5819 { 5820 5821 if (*mvp == NULL) 5822 return; 5823 5824 mtx_lock(&mp->mnt_listmtx); 5825 TAILQ_REMOVE(&mp->mnt_activevnodelist, *mvp, v_actfreelist); 5826 mtx_unlock(&mp->mnt_listmtx); 5827 mnt_vnode_markerfree_active(mvp, mp); 5828 } 5829