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