1 /*- 2 * Copyright (c) 1989, 1993 3 * The Regents of the University of California. All rights reserved. 4 * (c) UNIX System Laboratories, Inc. 5 * All or some portions of this file are derived from material licensed 6 * to the University of California by American Telephone and Telegraph 7 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 8 * the permission of UNIX System Laboratories, Inc. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 4. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * @(#)vfs_subr.c 8.31 (Berkeley) 5/26/95 35 */ 36 37 /* 38 * External virtual filesystem routines 39 */ 40 41 #include <sys/cdefs.h> 42 __FBSDID("$FreeBSD$"); 43 44 #include "opt_compat.h" 45 #include "opt_ddb.h" 46 #include "opt_watchdog.h" 47 48 #include <sys/param.h> 49 #include <sys/systm.h> 50 #include <sys/bio.h> 51 #include <sys/buf.h> 52 #include <sys/condvar.h> 53 #include <sys/conf.h> 54 #include <sys/dirent.h> 55 #include <sys/event.h> 56 #include <sys/eventhandler.h> 57 #include <sys/extattr.h> 58 #include <sys/file.h> 59 #include <sys/fcntl.h> 60 #include <sys/jail.h> 61 #include <sys/kdb.h> 62 #include <sys/kernel.h> 63 #include <sys/kthread.h> 64 #include <sys/lockf.h> 65 #include <sys/malloc.h> 66 #include <sys/mount.h> 67 #include <sys/namei.h> 68 #include <sys/pctrie.h> 69 #include <sys/priv.h> 70 #include <sys/reboot.h> 71 #include <sys/rwlock.h> 72 #include <sys/sched.h> 73 #include <sys/sleepqueue.h> 74 #include <sys/smp.h> 75 #include <sys/stat.h> 76 #include <sys/sysctl.h> 77 #include <sys/syslog.h> 78 #include <sys/vmmeter.h> 79 #include <sys/vnode.h> 80 #include <sys/watchdog.h> 81 82 #include <machine/stdarg.h> 83 84 #include <security/mac/mac_framework.h> 85 86 #include <vm/vm.h> 87 #include <vm/vm_object.h> 88 #include <vm/vm_extern.h> 89 #include <vm/pmap.h> 90 #include <vm/vm_map.h> 91 #include <vm/vm_page.h> 92 #include <vm/vm_kern.h> 93 #include <vm/uma.h> 94 95 #ifdef DDB 96 #include <ddb/ddb.h> 97 #endif 98 99 static void delmntque(struct vnode *vp); 100 static int flushbuflist(struct bufv *bufv, int flags, struct bufobj *bo, 101 int slpflag, int slptimeo); 102 static void syncer_shutdown(void *arg, int howto); 103 static int vtryrecycle(struct vnode *vp); 104 static void v_incr_usecount(struct vnode *); 105 static void v_decr_usecount(struct vnode *); 106 static void v_decr_useonly(struct vnode *); 107 static void v_upgrade_usecount(struct vnode *); 108 static void vnlru_free(int); 109 static void vgonel(struct vnode *); 110 static void vfs_knllock(void *arg); 111 static void vfs_knlunlock(void *arg); 112 static void vfs_knl_assert_locked(void *arg); 113 static void vfs_knl_assert_unlocked(void *arg); 114 static void destroy_vpollinfo(struct vpollinfo *vi); 115 116 /* 117 * Number of vnodes in existence. Increased whenever getnewvnode() 118 * allocates a new vnode, decreased in vdropl() for VI_DOOMED vnode. 119 */ 120 static unsigned long numvnodes; 121 122 SYSCTL_ULONG(_vfs, OID_AUTO, numvnodes, CTLFLAG_RD, &numvnodes, 0, 123 "Number of vnodes in existence"); 124 125 /* 126 * Conversion tables for conversion from vnode types to inode formats 127 * and back. 128 */ 129 enum vtype iftovt_tab[16] = { 130 VNON, VFIFO, VCHR, VNON, VDIR, VNON, VBLK, VNON, 131 VREG, VNON, VLNK, VNON, VSOCK, VNON, VNON, VBAD, 132 }; 133 int vttoif_tab[10] = { 134 0, S_IFREG, S_IFDIR, S_IFBLK, S_IFCHR, S_IFLNK, 135 S_IFSOCK, S_IFIFO, S_IFMT, S_IFMT 136 }; 137 138 /* 139 * List of vnodes that are ready for recycling. 140 */ 141 static TAILQ_HEAD(freelst, vnode) vnode_free_list; 142 143 /* 144 * Free vnode target. Free vnodes may simply be files which have been stat'd 145 * but not read. This is somewhat common, and a small cache of such files 146 * should be kept to avoid recreation costs. 147 */ 148 static u_long wantfreevnodes; 149 SYSCTL_ULONG(_vfs, OID_AUTO, wantfreevnodes, CTLFLAG_RW, &wantfreevnodes, 0, ""); 150 /* Number of vnodes in the free list. */ 151 static u_long freevnodes; 152 SYSCTL_ULONG(_vfs, OID_AUTO, freevnodes, CTLFLAG_RD, &freevnodes, 0, 153 "Number of vnodes in the free list"); 154 155 static int vlru_allow_cache_src; 156 SYSCTL_INT(_vfs, OID_AUTO, vlru_allow_cache_src, CTLFLAG_RW, 157 &vlru_allow_cache_src, 0, "Allow vlru to reclaim source vnode"); 158 159 /* 160 * Various variables used for debugging the new implementation of 161 * reassignbuf(). 162 * XXX these are probably of (very) limited utility now. 163 */ 164 static int reassignbufcalls; 165 SYSCTL_INT(_vfs, OID_AUTO, reassignbufcalls, CTLFLAG_RW, &reassignbufcalls, 0, 166 "Number of calls to reassignbuf"); 167 168 /* 169 * Cache for the mount type id assigned to NFS. This is used for 170 * special checks in nfs/nfs_nqlease.c and vm/vnode_pager.c. 171 */ 172 int nfs_mount_type = -1; 173 174 /* To keep more than one thread at a time from running vfs_getnewfsid */ 175 static struct mtx mntid_mtx; 176 177 /* 178 * Lock for any access to the following: 179 * vnode_free_list 180 * numvnodes 181 * freevnodes 182 */ 183 static struct mtx vnode_free_list_mtx; 184 185 /* Publicly exported FS */ 186 struct nfs_public nfs_pub; 187 188 static uma_zone_t buf_trie_zone; 189 190 /* Zone for allocation of new vnodes - used exclusively by getnewvnode() */ 191 static uma_zone_t vnode_zone; 192 static uma_zone_t vnodepoll_zone; 193 194 /* 195 * The workitem queue. 196 * 197 * It is useful to delay writes of file data and filesystem metadata 198 * for tens of seconds so that quickly created and deleted files need 199 * not waste disk bandwidth being created and removed. To realize this, 200 * we append vnodes to a "workitem" queue. When running with a soft 201 * updates implementation, most pending metadata dependencies should 202 * not wait for more than a few seconds. Thus, mounted on block devices 203 * are delayed only about a half the time that file data is delayed. 204 * Similarly, directory updates are more critical, so are only delayed 205 * about a third the time that file data is delayed. Thus, there are 206 * SYNCER_MAXDELAY queues that are processed round-robin at a rate of 207 * one each second (driven off the filesystem syncer process). The 208 * syncer_delayno variable indicates the next queue that is to be processed. 209 * Items that need to be processed soon are placed in this queue: 210 * 211 * syncer_workitem_pending[syncer_delayno] 212 * 213 * A delay of fifteen seconds is done by placing the request fifteen 214 * entries later in the queue: 215 * 216 * syncer_workitem_pending[(syncer_delayno + 15) & syncer_mask] 217 * 218 */ 219 static int syncer_delayno; 220 static long syncer_mask; 221 LIST_HEAD(synclist, bufobj); 222 static struct synclist *syncer_workitem_pending; 223 /* 224 * The sync_mtx protects: 225 * bo->bo_synclist 226 * sync_vnode_count 227 * syncer_delayno 228 * syncer_state 229 * syncer_workitem_pending 230 * syncer_worklist_len 231 * rushjob 232 */ 233 static struct mtx sync_mtx; 234 static struct cv sync_wakeup; 235 236 #define SYNCER_MAXDELAY 32 237 static int syncer_maxdelay = SYNCER_MAXDELAY; /* maximum delay time */ 238 static int syncdelay = 30; /* max time to delay syncing data */ 239 static int filedelay = 30; /* time to delay syncing files */ 240 SYSCTL_INT(_kern, OID_AUTO, filedelay, CTLFLAG_RW, &filedelay, 0, 241 "Time to delay syncing files (in seconds)"); 242 static int dirdelay = 29; /* time to delay syncing directories */ 243 SYSCTL_INT(_kern, OID_AUTO, dirdelay, CTLFLAG_RW, &dirdelay, 0, 244 "Time to delay syncing directories (in seconds)"); 245 static int metadelay = 28; /* time to delay syncing metadata */ 246 SYSCTL_INT(_kern, OID_AUTO, metadelay, CTLFLAG_RW, &metadelay, 0, 247 "Time to delay syncing metadata (in seconds)"); 248 static int rushjob; /* number of slots to run ASAP */ 249 static int stat_rush_requests; /* number of times I/O speeded up */ 250 SYSCTL_INT(_debug, OID_AUTO, rush_requests, CTLFLAG_RW, &stat_rush_requests, 0, 251 "Number of times I/O speeded up (rush requests)"); 252 253 /* 254 * When shutting down the syncer, run it at four times normal speed. 255 */ 256 #define SYNCER_SHUTDOWN_SPEEDUP 4 257 static int sync_vnode_count; 258 static int syncer_worklist_len; 259 static enum { SYNCER_RUNNING, SYNCER_SHUTTING_DOWN, SYNCER_FINAL_DELAY } 260 syncer_state; 261 262 /* 263 * Number of vnodes we want to exist at any one time. This is mostly used 264 * to size hash tables in vnode-related code. It is normally not used in 265 * getnewvnode(), as wantfreevnodes is normally nonzero.) 266 * 267 * XXX desiredvnodes is historical cruft and should not exist. 268 */ 269 int desiredvnodes; 270 SYSCTL_INT(_kern, KERN_MAXVNODES, maxvnodes, CTLFLAG_RW, 271 &desiredvnodes, 0, "Maximum number of vnodes"); 272 SYSCTL_ULONG(_kern, OID_AUTO, minvnodes, CTLFLAG_RW, 273 &wantfreevnodes, 0, "Minimum number of vnodes (legacy)"); 274 static int vnlru_nowhere; 275 SYSCTL_INT(_debug, OID_AUTO, vnlru_nowhere, CTLFLAG_RW, 276 &vnlru_nowhere, 0, "Number of times the vnlru process ran without success"); 277 278 /* 279 * Macros to control when a vnode is freed and recycled. All require 280 * the vnode interlock. 281 */ 282 #define VCANRECYCLE(vp) (((vp)->v_iflag & VI_FREE) && !(vp)->v_holdcnt) 283 #define VSHOULDFREE(vp) (!((vp)->v_iflag & VI_FREE) && !(vp)->v_holdcnt) 284 #define VSHOULDBUSY(vp) (((vp)->v_iflag & VI_FREE) && (vp)->v_holdcnt) 285 286 /* Shift count for (uintptr_t)vp to initialize vp->v_hash. */ 287 static int vnsz2log; 288 289 /* 290 * Support for the bufobj clean & dirty pctrie. 291 */ 292 static void * 293 buf_trie_alloc(struct pctrie *ptree) 294 { 295 296 return uma_zalloc(buf_trie_zone, M_NOWAIT); 297 } 298 299 static void 300 buf_trie_free(struct pctrie *ptree, void *node) 301 { 302 303 uma_zfree(buf_trie_zone, node); 304 } 305 PCTRIE_DEFINE(BUF, buf, b_lblkno, buf_trie_alloc, buf_trie_free); 306 307 /* 308 * Initialize the vnode management data structures. 309 * 310 * Reevaluate the following cap on the number of vnodes after the physical 311 * memory size exceeds 512GB. In the limit, as the physical memory size 312 * grows, the ratio of physical pages to vnodes approaches sixteen to one. 313 */ 314 #ifndef MAXVNODES_MAX 315 #define MAXVNODES_MAX (512 * (1024 * 1024 * 1024 / (int)PAGE_SIZE / 16)) 316 #endif 317 static void 318 vntblinit(void *dummy __unused) 319 { 320 u_int i; 321 int physvnodes, virtvnodes; 322 323 /* 324 * Desiredvnodes is a function of the physical memory size and the 325 * kernel's heap size. Generally speaking, it scales with the 326 * physical memory size. The ratio of desiredvnodes to physical pages 327 * is one to four until desiredvnodes exceeds 98,304. Thereafter, the 328 * marginal ratio of desiredvnodes to physical pages is one to 329 * sixteen. However, desiredvnodes is limited by the kernel's heap 330 * size. The memory required by desiredvnodes vnodes and vm objects 331 * may not exceed one seventh of the kernel's heap size. 332 */ 333 physvnodes = maxproc + vm_cnt.v_page_count / 16 + 3 * min(98304 * 4, 334 vm_cnt.v_page_count) / 16; 335 virtvnodes = vm_kmem_size / (7 * (sizeof(struct vm_object) + 336 sizeof(struct vnode))); 337 desiredvnodes = min(physvnodes, virtvnodes); 338 if (desiredvnodes > MAXVNODES_MAX) { 339 if (bootverbose) 340 printf("Reducing kern.maxvnodes %d -> %d\n", 341 desiredvnodes, MAXVNODES_MAX); 342 desiredvnodes = MAXVNODES_MAX; 343 } 344 wantfreevnodes = desiredvnodes / 4; 345 mtx_init(&mntid_mtx, "mntid", NULL, MTX_DEF); 346 TAILQ_INIT(&vnode_free_list); 347 mtx_init(&vnode_free_list_mtx, "vnode_free_list", NULL, MTX_DEF); 348 vnode_zone = uma_zcreate("VNODE", sizeof (struct vnode), NULL, NULL, 349 NULL, NULL, UMA_ALIGN_PTR, 0); 350 vnodepoll_zone = uma_zcreate("VNODEPOLL", sizeof (struct vpollinfo), 351 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); 352 /* 353 * Preallocate enough nodes to support one-per buf so that 354 * we can not fail an insert. reassignbuf() callers can not 355 * tolerate the insertion failure. 356 */ 357 buf_trie_zone = uma_zcreate("BUF TRIE", pctrie_node_size(), 358 NULL, NULL, pctrie_zone_init, NULL, UMA_ALIGN_PTR, 359 UMA_ZONE_NOFREE | UMA_ZONE_VM); 360 uma_prealloc(buf_trie_zone, nbuf); 361 /* 362 * Initialize the filesystem syncer. 363 */ 364 syncer_workitem_pending = hashinit(syncer_maxdelay, M_VNODE, 365 &syncer_mask); 366 syncer_maxdelay = syncer_mask + 1; 367 mtx_init(&sync_mtx, "Syncer mtx", NULL, MTX_DEF); 368 cv_init(&sync_wakeup, "syncer"); 369 for (i = 1; i <= sizeof(struct vnode); i <<= 1) 370 vnsz2log++; 371 vnsz2log--; 372 } 373 SYSINIT(vfs, SI_SUB_VFS, SI_ORDER_FIRST, vntblinit, NULL); 374 375 376 /* 377 * Mark a mount point as busy. Used to synchronize access and to delay 378 * unmounting. Eventually, mountlist_mtx is not released on failure. 379 * 380 * vfs_busy() is a custom lock, it can block the caller. 381 * vfs_busy() only sleeps if the unmount is active on the mount point. 382 * For a mountpoint mp, vfs_busy-enforced lock is before lock of any 383 * vnode belonging to mp. 384 * 385 * Lookup uses vfs_busy() to traverse mount points. 386 * root fs var fs 387 * / vnode lock A / vnode lock (/var) D 388 * /var vnode lock B /log vnode lock(/var/log) E 389 * vfs_busy lock C vfs_busy lock F 390 * 391 * Within each file system, the lock order is C->A->B and F->D->E. 392 * 393 * When traversing across mounts, the system follows that lock order: 394 * 395 * C->A->B 396 * | 397 * +->F->D->E 398 * 399 * The lookup() process for namei("/var") illustrates the process: 400 * VOP_LOOKUP() obtains B while A is held 401 * vfs_busy() obtains a shared lock on F while A and B are held 402 * vput() releases lock on B 403 * vput() releases lock on A 404 * VFS_ROOT() obtains lock on D while shared lock on F is held 405 * vfs_unbusy() releases shared lock on F 406 * vn_lock() obtains lock on deadfs vnode vp_crossmp instead of A. 407 * Attempt to lock A (instead of vp_crossmp) while D is held would 408 * violate the global order, causing deadlocks. 409 * 410 * dounmount() locks B while F is drained. 411 */ 412 int 413 vfs_busy(struct mount *mp, int flags) 414 { 415 416 MPASS((flags & ~MBF_MASK) == 0); 417 CTR3(KTR_VFS, "%s: mp %p with flags %d", __func__, mp, flags); 418 419 MNT_ILOCK(mp); 420 MNT_REF(mp); 421 /* 422 * If mount point is currenly being unmounted, sleep until the 423 * mount point fate is decided. If thread doing the unmounting fails, 424 * it will clear MNTK_UNMOUNT flag before waking us up, indicating 425 * that this mount point has survived the unmount attempt and vfs_busy 426 * should retry. Otherwise the unmounter thread will set MNTK_REFEXPIRE 427 * flag in addition to MNTK_UNMOUNT, indicating that mount point is 428 * about to be really destroyed. vfs_busy needs to release its 429 * reference on the mount point in this case and return with ENOENT, 430 * telling the caller that mount mount it tried to busy is no longer 431 * valid. 432 */ 433 while (mp->mnt_kern_flag & MNTK_UNMOUNT) { 434 if (flags & MBF_NOWAIT || mp->mnt_kern_flag & MNTK_REFEXPIRE) { 435 MNT_REL(mp); 436 MNT_IUNLOCK(mp); 437 CTR1(KTR_VFS, "%s: failed busying before sleeping", 438 __func__); 439 return (ENOENT); 440 } 441 if (flags & MBF_MNTLSTLOCK) 442 mtx_unlock(&mountlist_mtx); 443 mp->mnt_kern_flag |= MNTK_MWAIT; 444 msleep(mp, MNT_MTX(mp), PVFS | PDROP, "vfs_busy", 0); 445 if (flags & MBF_MNTLSTLOCK) 446 mtx_lock(&mountlist_mtx); 447 MNT_ILOCK(mp); 448 } 449 if (flags & MBF_MNTLSTLOCK) 450 mtx_unlock(&mountlist_mtx); 451 mp->mnt_lockref++; 452 MNT_IUNLOCK(mp); 453 return (0); 454 } 455 456 /* 457 * Free a busy filesystem. 458 */ 459 void 460 vfs_unbusy(struct mount *mp) 461 { 462 463 CTR2(KTR_VFS, "%s: mp %p", __func__, mp); 464 MNT_ILOCK(mp); 465 MNT_REL(mp); 466 KASSERT(mp->mnt_lockref > 0, ("negative mnt_lockref")); 467 mp->mnt_lockref--; 468 if (mp->mnt_lockref == 0 && (mp->mnt_kern_flag & MNTK_DRAINING) != 0) { 469 MPASS(mp->mnt_kern_flag & MNTK_UNMOUNT); 470 CTR1(KTR_VFS, "%s: waking up waiters", __func__); 471 mp->mnt_kern_flag &= ~MNTK_DRAINING; 472 wakeup(&mp->mnt_lockref); 473 } 474 MNT_IUNLOCK(mp); 475 } 476 477 /* 478 * Lookup a mount point by filesystem identifier. 479 */ 480 struct mount * 481 vfs_getvfs(fsid_t *fsid) 482 { 483 struct mount *mp; 484 485 CTR2(KTR_VFS, "%s: fsid %p", __func__, fsid); 486 mtx_lock(&mountlist_mtx); 487 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 488 if (mp->mnt_stat.f_fsid.val[0] == fsid->val[0] && 489 mp->mnt_stat.f_fsid.val[1] == fsid->val[1]) { 490 vfs_ref(mp); 491 mtx_unlock(&mountlist_mtx); 492 return (mp); 493 } 494 } 495 mtx_unlock(&mountlist_mtx); 496 CTR2(KTR_VFS, "%s: lookup failed for %p id", __func__, fsid); 497 return ((struct mount *) 0); 498 } 499 500 /* 501 * Lookup a mount point by filesystem identifier, busying it before 502 * returning. 503 */ 504 struct mount * 505 vfs_busyfs(fsid_t *fsid) 506 { 507 struct mount *mp; 508 int error; 509 510 CTR2(KTR_VFS, "%s: fsid %p", __func__, fsid); 511 mtx_lock(&mountlist_mtx); 512 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 513 if (mp->mnt_stat.f_fsid.val[0] == fsid->val[0] && 514 mp->mnt_stat.f_fsid.val[1] == fsid->val[1]) { 515 error = vfs_busy(mp, MBF_MNTLSTLOCK); 516 if (error) { 517 mtx_unlock(&mountlist_mtx); 518 return (NULL); 519 } 520 return (mp); 521 } 522 } 523 CTR2(KTR_VFS, "%s: lookup failed for %p id", __func__, fsid); 524 mtx_unlock(&mountlist_mtx); 525 return ((struct mount *) 0); 526 } 527 528 /* 529 * Check if a user can access privileged mount options. 530 */ 531 int 532 vfs_suser(struct mount *mp, struct thread *td) 533 { 534 int error; 535 536 /* 537 * If the thread is jailed, but this is not a jail-friendly file 538 * system, deny immediately. 539 */ 540 if (!(mp->mnt_vfc->vfc_flags & VFCF_JAIL) && jailed(td->td_ucred)) 541 return (EPERM); 542 543 /* 544 * If the file system was mounted outside the jail of the calling 545 * thread, deny immediately. 546 */ 547 if (prison_check(td->td_ucred, mp->mnt_cred) != 0) 548 return (EPERM); 549 550 /* 551 * If file system supports delegated administration, we don't check 552 * for the PRIV_VFS_MOUNT_OWNER privilege - it will be better verified 553 * by the file system itself. 554 * If this is not the user that did original mount, we check for 555 * the PRIV_VFS_MOUNT_OWNER privilege. 556 */ 557 if (!(mp->mnt_vfc->vfc_flags & VFCF_DELEGADMIN) && 558 mp->mnt_cred->cr_uid != td->td_ucred->cr_uid) { 559 if ((error = priv_check(td, PRIV_VFS_MOUNT_OWNER)) != 0) 560 return (error); 561 } 562 return (0); 563 } 564 565 /* 566 * Get a new unique fsid. Try to make its val[0] unique, since this value 567 * will be used to create fake device numbers for stat(). Also try (but 568 * not so hard) make its val[0] unique mod 2^16, since some emulators only 569 * support 16-bit device numbers. We end up with unique val[0]'s for the 570 * first 2^16 calls and unique val[0]'s mod 2^16 for the first 2^8 calls. 571 * 572 * Keep in mind that several mounts may be running in parallel. Starting 573 * the search one past where the previous search terminated is both a 574 * micro-optimization and a defense against returning the same fsid to 575 * different mounts. 576 */ 577 void 578 vfs_getnewfsid(struct mount *mp) 579 { 580 static uint16_t mntid_base; 581 struct mount *nmp; 582 fsid_t tfsid; 583 int mtype; 584 585 CTR2(KTR_VFS, "%s: mp %p", __func__, mp); 586 mtx_lock(&mntid_mtx); 587 mtype = mp->mnt_vfc->vfc_typenum; 588 tfsid.val[1] = mtype; 589 mtype = (mtype & 0xFF) << 24; 590 for (;;) { 591 tfsid.val[0] = makedev(255, 592 mtype | ((mntid_base & 0xFF00) << 8) | (mntid_base & 0xFF)); 593 mntid_base++; 594 if ((nmp = vfs_getvfs(&tfsid)) == NULL) 595 break; 596 vfs_rel(nmp); 597 } 598 mp->mnt_stat.f_fsid.val[0] = tfsid.val[0]; 599 mp->mnt_stat.f_fsid.val[1] = tfsid.val[1]; 600 mtx_unlock(&mntid_mtx); 601 } 602 603 /* 604 * Knob to control the precision of file timestamps: 605 * 606 * 0 = seconds only; nanoseconds zeroed. 607 * 1 = seconds and nanoseconds, accurate within 1/HZ. 608 * 2 = seconds and nanoseconds, truncated to microseconds. 609 * >=3 = seconds and nanoseconds, maximum precision. 610 */ 611 enum { TSP_SEC, TSP_HZ, TSP_USEC, TSP_NSEC }; 612 613 static int timestamp_precision = TSP_SEC; 614 SYSCTL_INT(_vfs, OID_AUTO, timestamp_precision, CTLFLAG_RW, 615 ×tamp_precision, 0, "File timestamp precision (0: seconds, " 616 "1: sec + ns accurate to 1/HZ, 2: sec + ns truncated to ms, " 617 "3+: sec + ns (max. precision))"); 618 619 /* 620 * Get a current timestamp. 621 */ 622 void 623 vfs_timestamp(struct timespec *tsp) 624 { 625 struct timeval tv; 626 627 switch (timestamp_precision) { 628 case TSP_SEC: 629 tsp->tv_sec = time_second; 630 tsp->tv_nsec = 0; 631 break; 632 case TSP_HZ: 633 getnanotime(tsp); 634 break; 635 case TSP_USEC: 636 microtime(&tv); 637 TIMEVAL_TO_TIMESPEC(&tv, tsp); 638 break; 639 case TSP_NSEC: 640 default: 641 nanotime(tsp); 642 break; 643 } 644 } 645 646 /* 647 * Set vnode attributes to VNOVAL 648 */ 649 void 650 vattr_null(struct vattr *vap) 651 { 652 653 vap->va_type = VNON; 654 vap->va_size = VNOVAL; 655 vap->va_bytes = VNOVAL; 656 vap->va_mode = VNOVAL; 657 vap->va_nlink = VNOVAL; 658 vap->va_uid = VNOVAL; 659 vap->va_gid = VNOVAL; 660 vap->va_fsid = VNOVAL; 661 vap->va_fileid = VNOVAL; 662 vap->va_blocksize = VNOVAL; 663 vap->va_rdev = VNOVAL; 664 vap->va_atime.tv_sec = VNOVAL; 665 vap->va_atime.tv_nsec = VNOVAL; 666 vap->va_mtime.tv_sec = VNOVAL; 667 vap->va_mtime.tv_nsec = VNOVAL; 668 vap->va_ctime.tv_sec = VNOVAL; 669 vap->va_ctime.tv_nsec = VNOVAL; 670 vap->va_birthtime.tv_sec = VNOVAL; 671 vap->va_birthtime.tv_nsec = VNOVAL; 672 vap->va_flags = VNOVAL; 673 vap->va_gen = VNOVAL; 674 vap->va_vaflags = 0; 675 } 676 677 /* 678 * This routine is called when we have too many vnodes. It attempts 679 * to free <count> vnodes and will potentially free vnodes that still 680 * have VM backing store (VM backing store is typically the cause 681 * of a vnode blowout so we want to do this). Therefore, this operation 682 * is not considered cheap. 683 * 684 * A number of conditions may prevent a vnode from being reclaimed. 685 * the buffer cache may have references on the vnode, a directory 686 * vnode may still have references due to the namei cache representing 687 * underlying files, or the vnode may be in active use. It is not 688 * desireable to reuse such vnodes. These conditions may cause the 689 * number of vnodes to reach some minimum value regardless of what 690 * you set kern.maxvnodes to. Do not set kern.maxvnodes too low. 691 */ 692 static int 693 vlrureclaim(struct mount *mp) 694 { 695 struct vnode *vp; 696 int done; 697 int trigger; 698 int usevnodes; 699 int count; 700 701 /* 702 * Calculate the trigger point, don't allow user 703 * screwups to blow us up. This prevents us from 704 * recycling vnodes with lots of resident pages. We 705 * aren't trying to free memory, we are trying to 706 * free vnodes. 707 */ 708 usevnodes = desiredvnodes; 709 if (usevnodes <= 0) 710 usevnodes = 1; 711 trigger = vm_cnt.v_page_count * 2 / usevnodes; 712 done = 0; 713 vn_start_write(NULL, &mp, V_WAIT); 714 MNT_ILOCK(mp); 715 count = mp->mnt_nvnodelistsize / 10 + 1; 716 while (count != 0) { 717 vp = TAILQ_FIRST(&mp->mnt_nvnodelist); 718 while (vp != NULL && vp->v_type == VMARKER) 719 vp = TAILQ_NEXT(vp, v_nmntvnodes); 720 if (vp == NULL) 721 break; 722 TAILQ_REMOVE(&mp->mnt_nvnodelist, vp, v_nmntvnodes); 723 TAILQ_INSERT_TAIL(&mp->mnt_nvnodelist, vp, v_nmntvnodes); 724 --count; 725 if (!VI_TRYLOCK(vp)) 726 goto next_iter; 727 /* 728 * If it's been deconstructed already, it's still 729 * referenced, or it exceeds the trigger, skip it. 730 */ 731 if (vp->v_usecount || 732 (!vlru_allow_cache_src && 733 !LIST_EMPTY(&(vp)->v_cache_src)) || 734 (vp->v_iflag & VI_DOOMED) != 0 || (vp->v_object != NULL && 735 vp->v_object->resident_page_count > trigger)) { 736 VI_UNLOCK(vp); 737 goto next_iter; 738 } 739 MNT_IUNLOCK(mp); 740 vholdl(vp); 741 if (VOP_LOCK(vp, LK_INTERLOCK|LK_EXCLUSIVE|LK_NOWAIT)) { 742 vdrop(vp); 743 goto next_iter_mntunlocked; 744 } 745 VI_LOCK(vp); 746 /* 747 * v_usecount may have been bumped after VOP_LOCK() dropped 748 * the vnode interlock and before it was locked again. 749 * 750 * It is not necessary to recheck VI_DOOMED because it can 751 * only be set by another thread that holds both the vnode 752 * lock and vnode interlock. If another thread has the 753 * vnode lock before we get to VOP_LOCK() and obtains the 754 * vnode interlock after VOP_LOCK() drops the vnode 755 * interlock, the other thread will be unable to drop the 756 * vnode lock before our VOP_LOCK() call fails. 757 */ 758 if (vp->v_usecount || 759 (!vlru_allow_cache_src && 760 !LIST_EMPTY(&(vp)->v_cache_src)) || 761 (vp->v_object != NULL && 762 vp->v_object->resident_page_count > trigger)) { 763 VOP_UNLOCK(vp, LK_INTERLOCK); 764 vdrop(vp); 765 goto next_iter_mntunlocked; 766 } 767 KASSERT((vp->v_iflag & VI_DOOMED) == 0, 768 ("VI_DOOMED unexpectedly detected in vlrureclaim()")); 769 vgonel(vp); 770 VOP_UNLOCK(vp, 0); 771 vdropl(vp); 772 done++; 773 next_iter_mntunlocked: 774 if (!should_yield()) 775 goto relock_mnt; 776 goto yield; 777 next_iter: 778 if (!should_yield()) 779 continue; 780 MNT_IUNLOCK(mp); 781 yield: 782 kern_yield(PRI_USER); 783 relock_mnt: 784 MNT_ILOCK(mp); 785 } 786 MNT_IUNLOCK(mp); 787 vn_finished_write(mp); 788 return done; 789 } 790 791 /* 792 * Attempt to keep the free list at wantfreevnodes length. 793 */ 794 static void 795 vnlru_free(int count) 796 { 797 struct vnode *vp; 798 799 mtx_assert(&vnode_free_list_mtx, MA_OWNED); 800 for (; count > 0; count--) { 801 vp = TAILQ_FIRST(&vnode_free_list); 802 /* 803 * The list can be modified while the free_list_mtx 804 * has been dropped and vp could be NULL here. 805 */ 806 if (!vp) 807 break; 808 VNASSERT(vp->v_op != NULL, vp, 809 ("vnlru_free: vnode already reclaimed.")); 810 KASSERT((vp->v_iflag & VI_FREE) != 0, 811 ("Removing vnode not on freelist")); 812 KASSERT((vp->v_iflag & VI_ACTIVE) == 0, 813 ("Mangling active vnode")); 814 TAILQ_REMOVE(&vnode_free_list, vp, v_actfreelist); 815 /* 816 * Don't recycle if we can't get the interlock. 817 */ 818 if (!VI_TRYLOCK(vp)) { 819 TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_actfreelist); 820 continue; 821 } 822 VNASSERT(VCANRECYCLE(vp), vp, 823 ("vp inconsistent on freelist")); 824 freevnodes--; 825 vp->v_iflag &= ~VI_FREE; 826 vholdl(vp); 827 mtx_unlock(&vnode_free_list_mtx); 828 VI_UNLOCK(vp); 829 vtryrecycle(vp); 830 /* 831 * If the recycled succeeded this vdrop will actually free 832 * the vnode. If not it will simply place it back on 833 * the free list. 834 */ 835 vdrop(vp); 836 mtx_lock(&vnode_free_list_mtx); 837 } 838 } 839 /* 840 * Attempt to recycle vnodes in a context that is always safe to block. 841 * Calling vlrurecycle() from the bowels of filesystem code has some 842 * interesting deadlock problems. 843 */ 844 static struct proc *vnlruproc; 845 static int vnlruproc_sig; 846 847 static void 848 vnlru_proc(void) 849 { 850 struct mount *mp, *nmp; 851 int done; 852 struct proc *p = vnlruproc; 853 854 EVENTHANDLER_REGISTER(shutdown_pre_sync, kproc_shutdown, p, 855 SHUTDOWN_PRI_FIRST); 856 857 for (;;) { 858 kproc_suspend_check(p); 859 mtx_lock(&vnode_free_list_mtx); 860 if (freevnodes > wantfreevnodes) 861 vnlru_free(freevnodes - wantfreevnodes); 862 if (numvnodes <= desiredvnodes * 9 / 10) { 863 vnlruproc_sig = 0; 864 wakeup(&vnlruproc_sig); 865 msleep(vnlruproc, &vnode_free_list_mtx, 866 PVFS|PDROP, "vlruwt", hz); 867 continue; 868 } 869 mtx_unlock(&vnode_free_list_mtx); 870 done = 0; 871 mtx_lock(&mountlist_mtx); 872 for (mp = TAILQ_FIRST(&mountlist); mp != NULL; mp = nmp) { 873 if (vfs_busy(mp, MBF_NOWAIT | MBF_MNTLSTLOCK)) { 874 nmp = TAILQ_NEXT(mp, mnt_list); 875 continue; 876 } 877 done += vlrureclaim(mp); 878 mtx_lock(&mountlist_mtx); 879 nmp = TAILQ_NEXT(mp, mnt_list); 880 vfs_unbusy(mp); 881 } 882 mtx_unlock(&mountlist_mtx); 883 if (done == 0) { 884 #if 0 885 /* These messages are temporary debugging aids */ 886 if (vnlru_nowhere < 5) 887 printf("vnlru process getting nowhere..\n"); 888 else if (vnlru_nowhere == 5) 889 printf("vnlru process messages stopped.\n"); 890 #endif 891 vnlru_nowhere++; 892 tsleep(vnlruproc, PPAUSE, "vlrup", hz * 3); 893 } else 894 kern_yield(PRI_USER); 895 } 896 } 897 898 static struct kproc_desc vnlru_kp = { 899 "vnlru", 900 vnlru_proc, 901 &vnlruproc 902 }; 903 SYSINIT(vnlru, SI_SUB_KTHREAD_UPDATE, SI_ORDER_FIRST, kproc_start, 904 &vnlru_kp); 905 906 /* 907 * Routines having to do with the management of the vnode table. 908 */ 909 910 /* 911 * Try to recycle a freed vnode. We abort if anyone picks up a reference 912 * before we actually vgone(). This function must be called with the vnode 913 * held to prevent the vnode from being returned to the free list midway 914 * through vgone(). 915 */ 916 static int 917 vtryrecycle(struct vnode *vp) 918 { 919 struct mount *vnmp; 920 921 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 922 VNASSERT(vp->v_holdcnt, vp, 923 ("vtryrecycle: Recycling vp %p without a reference.", vp)); 924 /* 925 * This vnode may found and locked via some other list, if so we 926 * can't recycle it yet. 927 */ 928 if (VOP_LOCK(vp, LK_EXCLUSIVE | LK_NOWAIT) != 0) { 929 CTR2(KTR_VFS, 930 "%s: impossible to recycle, vp %p lock is already held", 931 __func__, vp); 932 return (EWOULDBLOCK); 933 } 934 /* 935 * Don't recycle if its filesystem is being suspended. 936 */ 937 if (vn_start_write(vp, &vnmp, V_NOWAIT) != 0) { 938 VOP_UNLOCK(vp, 0); 939 CTR2(KTR_VFS, 940 "%s: impossible to recycle, cannot start the write for %p", 941 __func__, vp); 942 return (EBUSY); 943 } 944 /* 945 * If we got this far, we need to acquire the interlock and see if 946 * anyone picked up this vnode from another list. If not, we will 947 * mark it with DOOMED via vgonel() so that anyone who does find it 948 * will skip over it. 949 */ 950 VI_LOCK(vp); 951 if (vp->v_usecount) { 952 VOP_UNLOCK(vp, LK_INTERLOCK); 953 vn_finished_write(vnmp); 954 CTR2(KTR_VFS, 955 "%s: impossible to recycle, %p is already referenced", 956 __func__, vp); 957 return (EBUSY); 958 } 959 if ((vp->v_iflag & VI_DOOMED) == 0) 960 vgonel(vp); 961 VOP_UNLOCK(vp, LK_INTERLOCK); 962 vn_finished_write(vnmp); 963 return (0); 964 } 965 966 /* 967 * Wait for available vnodes. 968 */ 969 static int 970 getnewvnode_wait(int suspended) 971 { 972 973 mtx_assert(&vnode_free_list_mtx, MA_OWNED); 974 if (numvnodes > desiredvnodes) { 975 if (suspended) { 976 /* 977 * File system is beeing suspended, we cannot risk a 978 * deadlock here, so allocate new vnode anyway. 979 */ 980 if (freevnodes > wantfreevnodes) 981 vnlru_free(freevnodes - wantfreevnodes); 982 return (0); 983 } 984 if (vnlruproc_sig == 0) { 985 vnlruproc_sig = 1; /* avoid unnecessary wakeups */ 986 wakeup(vnlruproc); 987 } 988 msleep(&vnlruproc_sig, &vnode_free_list_mtx, PVFS, 989 "vlruwk", hz); 990 } 991 return (numvnodes > desiredvnodes ? ENFILE : 0); 992 } 993 994 void 995 getnewvnode_reserve(u_int count) 996 { 997 struct thread *td; 998 999 td = curthread; 1000 mtx_lock(&vnode_free_list_mtx); 1001 while (count > 0) { 1002 if (getnewvnode_wait(0) == 0) { 1003 count--; 1004 td->td_vp_reserv++; 1005 numvnodes++; 1006 } 1007 } 1008 mtx_unlock(&vnode_free_list_mtx); 1009 } 1010 1011 void 1012 getnewvnode_drop_reserve(void) 1013 { 1014 struct thread *td; 1015 1016 td = curthread; 1017 mtx_lock(&vnode_free_list_mtx); 1018 KASSERT(numvnodes >= td->td_vp_reserv, ("reserve too large")); 1019 numvnodes -= td->td_vp_reserv; 1020 mtx_unlock(&vnode_free_list_mtx); 1021 td->td_vp_reserv = 0; 1022 } 1023 1024 /* 1025 * Return the next vnode from the free list. 1026 */ 1027 int 1028 getnewvnode(const char *tag, struct mount *mp, struct vop_vector *vops, 1029 struct vnode **vpp) 1030 { 1031 struct vnode *vp; 1032 struct bufobj *bo; 1033 struct thread *td; 1034 int error; 1035 1036 CTR3(KTR_VFS, "%s: mp %p with tag %s", __func__, mp, tag); 1037 vp = NULL; 1038 td = curthread; 1039 if (td->td_vp_reserv > 0) { 1040 td->td_vp_reserv -= 1; 1041 goto alloc; 1042 } 1043 mtx_lock(&vnode_free_list_mtx); 1044 /* 1045 * Lend our context to reclaim vnodes if they've exceeded the max. 1046 */ 1047 if (freevnodes > wantfreevnodes) 1048 vnlru_free(1); 1049 error = getnewvnode_wait(mp != NULL && (mp->mnt_kern_flag & 1050 MNTK_SUSPEND)); 1051 #if 0 /* XXX Not all VFS_VGET/ffs_vget callers check returns. */ 1052 if (error != 0) { 1053 mtx_unlock(&vnode_free_list_mtx); 1054 return (error); 1055 } 1056 #endif 1057 numvnodes++; 1058 mtx_unlock(&vnode_free_list_mtx); 1059 alloc: 1060 vp = (struct vnode *) uma_zalloc(vnode_zone, M_WAITOK|M_ZERO); 1061 /* 1062 * Setup locks. 1063 */ 1064 vp->v_vnlock = &vp->v_lock; 1065 mtx_init(&vp->v_interlock, "vnode interlock", NULL, MTX_DEF); 1066 /* 1067 * By default, don't allow shared locks unless filesystems 1068 * opt-in. 1069 */ 1070 lockinit(vp->v_vnlock, PVFS, tag, VLKTIMEOUT, LK_NOSHARE | LK_IS_VNODE); 1071 /* 1072 * Initialize bufobj. 1073 */ 1074 bo = &vp->v_bufobj; 1075 bo->__bo_vnode = vp; 1076 rw_init(BO_LOCKPTR(bo), "bufobj interlock"); 1077 bo->bo_ops = &buf_ops_bio; 1078 bo->bo_private = vp; 1079 TAILQ_INIT(&bo->bo_clean.bv_hd); 1080 TAILQ_INIT(&bo->bo_dirty.bv_hd); 1081 /* 1082 * Initialize namecache. 1083 */ 1084 LIST_INIT(&vp->v_cache_src); 1085 TAILQ_INIT(&vp->v_cache_dst); 1086 /* 1087 * Finalize various vnode identity bits. 1088 */ 1089 vp->v_type = VNON; 1090 vp->v_tag = tag; 1091 vp->v_op = vops; 1092 v_incr_usecount(vp); 1093 vp->v_data = NULL; 1094 #ifdef MAC 1095 mac_vnode_init(vp); 1096 if (mp != NULL && (mp->mnt_flag & MNT_MULTILABEL) == 0) 1097 mac_vnode_associate_singlelabel(mp, vp); 1098 else if (mp == NULL && vops != &dead_vnodeops) 1099 printf("NULL mp in getnewvnode()\n"); 1100 #endif 1101 if (mp != NULL) { 1102 bo->bo_bsize = mp->mnt_stat.f_iosize; 1103 if ((mp->mnt_kern_flag & MNTK_NOKNOTE) != 0) 1104 vp->v_vflag |= VV_NOKNOTE; 1105 } 1106 rangelock_init(&vp->v_rl); 1107 1108 /* 1109 * For the filesystems which do not use vfs_hash_insert(), 1110 * still initialize v_hash to have vfs_hash_index() useful. 1111 * E.g., nullfs uses vfs_hash_index() on the lower vnode for 1112 * its own hashing. 1113 */ 1114 vp->v_hash = (uintptr_t)vp >> vnsz2log; 1115 1116 *vpp = vp; 1117 return (0); 1118 } 1119 1120 /* 1121 * Delete from old mount point vnode list, if on one. 1122 */ 1123 static void 1124 delmntque(struct vnode *vp) 1125 { 1126 struct mount *mp; 1127 int active; 1128 1129 mp = vp->v_mount; 1130 if (mp == NULL) 1131 return; 1132 MNT_ILOCK(mp); 1133 VI_LOCK(vp); 1134 KASSERT(mp->mnt_activevnodelistsize <= mp->mnt_nvnodelistsize, 1135 ("Active vnode list size %d > Vnode list size %d", 1136 mp->mnt_activevnodelistsize, mp->mnt_nvnodelistsize)); 1137 active = vp->v_iflag & VI_ACTIVE; 1138 vp->v_iflag &= ~VI_ACTIVE; 1139 if (active) { 1140 mtx_lock(&vnode_free_list_mtx); 1141 TAILQ_REMOVE(&mp->mnt_activevnodelist, vp, v_actfreelist); 1142 mp->mnt_activevnodelistsize--; 1143 mtx_unlock(&vnode_free_list_mtx); 1144 } 1145 vp->v_mount = NULL; 1146 VI_UNLOCK(vp); 1147 VNASSERT(mp->mnt_nvnodelistsize > 0, vp, 1148 ("bad mount point vnode list size")); 1149 TAILQ_REMOVE(&mp->mnt_nvnodelist, vp, v_nmntvnodes); 1150 mp->mnt_nvnodelistsize--; 1151 MNT_REL(mp); 1152 MNT_IUNLOCK(mp); 1153 } 1154 1155 static void 1156 insmntque_stddtr(struct vnode *vp, void *dtr_arg) 1157 { 1158 1159 vp->v_data = NULL; 1160 vp->v_op = &dead_vnodeops; 1161 vgone(vp); 1162 vput(vp); 1163 } 1164 1165 /* 1166 * Insert into list of vnodes for the new mount point, if available. 1167 */ 1168 int 1169 insmntque1(struct vnode *vp, struct mount *mp, 1170 void (*dtr)(struct vnode *, void *), void *dtr_arg) 1171 { 1172 1173 KASSERT(vp->v_mount == NULL, 1174 ("insmntque: vnode already on per mount vnode list")); 1175 VNASSERT(mp != NULL, vp, ("Don't call insmntque(foo, NULL)")); 1176 ASSERT_VOP_ELOCKED(vp, "insmntque: non-locked vp"); 1177 1178 /* 1179 * We acquire the vnode interlock early to ensure that the 1180 * vnode cannot be recycled by another process releasing a 1181 * holdcnt on it before we get it on both the vnode list 1182 * and the active vnode list. The mount mutex protects only 1183 * manipulation of the vnode list and the vnode freelist 1184 * mutex protects only manipulation of the active vnode list. 1185 * Hence the need to hold the vnode interlock throughout. 1186 */ 1187 MNT_ILOCK(mp); 1188 VI_LOCK(vp); 1189 if (((mp->mnt_kern_flag & MNTK_NOINSMNTQ) != 0 && 1190 ((mp->mnt_kern_flag & MNTK_UNMOUNTF) != 0 || 1191 mp->mnt_nvnodelistsize == 0)) && 1192 (vp->v_vflag & VV_FORCEINSMQ) == 0) { 1193 VI_UNLOCK(vp); 1194 MNT_IUNLOCK(mp); 1195 if (dtr != NULL) 1196 dtr(vp, dtr_arg); 1197 return (EBUSY); 1198 } 1199 vp->v_mount = mp; 1200 MNT_REF(mp); 1201 TAILQ_INSERT_TAIL(&mp->mnt_nvnodelist, vp, v_nmntvnodes); 1202 VNASSERT(mp->mnt_nvnodelistsize >= 0, vp, 1203 ("neg mount point vnode list size")); 1204 mp->mnt_nvnodelistsize++; 1205 KASSERT((vp->v_iflag & VI_ACTIVE) == 0, 1206 ("Activating already active vnode")); 1207 vp->v_iflag |= VI_ACTIVE; 1208 mtx_lock(&vnode_free_list_mtx); 1209 TAILQ_INSERT_HEAD(&mp->mnt_activevnodelist, vp, v_actfreelist); 1210 mp->mnt_activevnodelistsize++; 1211 mtx_unlock(&vnode_free_list_mtx); 1212 VI_UNLOCK(vp); 1213 MNT_IUNLOCK(mp); 1214 return (0); 1215 } 1216 1217 int 1218 insmntque(struct vnode *vp, struct mount *mp) 1219 { 1220 1221 return (insmntque1(vp, mp, insmntque_stddtr, NULL)); 1222 } 1223 1224 /* 1225 * Flush out and invalidate all buffers associated with a bufobj 1226 * Called with the underlying object locked. 1227 */ 1228 int 1229 bufobj_invalbuf(struct bufobj *bo, int flags, int slpflag, int slptimeo) 1230 { 1231 int error; 1232 1233 BO_LOCK(bo); 1234 if (flags & V_SAVE) { 1235 error = bufobj_wwait(bo, slpflag, slptimeo); 1236 if (error) { 1237 BO_UNLOCK(bo); 1238 return (error); 1239 } 1240 if (bo->bo_dirty.bv_cnt > 0) { 1241 BO_UNLOCK(bo); 1242 if ((error = BO_SYNC(bo, MNT_WAIT)) != 0) 1243 return (error); 1244 /* 1245 * XXX We could save a lock/unlock if this was only 1246 * enabled under INVARIANTS 1247 */ 1248 BO_LOCK(bo); 1249 if (bo->bo_numoutput > 0 || bo->bo_dirty.bv_cnt > 0) 1250 panic("vinvalbuf: dirty bufs"); 1251 } 1252 } 1253 /* 1254 * If you alter this loop please notice that interlock is dropped and 1255 * reacquired in flushbuflist. Special care is needed to ensure that 1256 * no race conditions occur from this. 1257 */ 1258 do { 1259 error = flushbuflist(&bo->bo_clean, 1260 flags, bo, slpflag, slptimeo); 1261 if (error == 0 && !(flags & V_CLEANONLY)) 1262 error = flushbuflist(&bo->bo_dirty, 1263 flags, bo, slpflag, slptimeo); 1264 if (error != 0 && error != EAGAIN) { 1265 BO_UNLOCK(bo); 1266 return (error); 1267 } 1268 } while (error != 0); 1269 1270 /* 1271 * Wait for I/O to complete. XXX needs cleaning up. The vnode can 1272 * have write I/O in-progress but if there is a VM object then the 1273 * VM object can also have read-I/O in-progress. 1274 */ 1275 do { 1276 bufobj_wwait(bo, 0, 0); 1277 BO_UNLOCK(bo); 1278 if (bo->bo_object != NULL) { 1279 VM_OBJECT_WLOCK(bo->bo_object); 1280 vm_object_pip_wait(bo->bo_object, "bovlbx"); 1281 VM_OBJECT_WUNLOCK(bo->bo_object); 1282 } 1283 BO_LOCK(bo); 1284 } while (bo->bo_numoutput > 0); 1285 BO_UNLOCK(bo); 1286 1287 /* 1288 * Destroy the copy in the VM cache, too. 1289 */ 1290 if (bo->bo_object != NULL && 1291 (flags & (V_ALT | V_NORMAL | V_CLEANONLY)) == 0) { 1292 VM_OBJECT_WLOCK(bo->bo_object); 1293 vm_object_page_remove(bo->bo_object, 0, 0, (flags & V_SAVE) ? 1294 OBJPR_CLEANONLY : 0); 1295 VM_OBJECT_WUNLOCK(bo->bo_object); 1296 } 1297 1298 #ifdef INVARIANTS 1299 BO_LOCK(bo); 1300 if ((flags & (V_ALT | V_NORMAL | V_CLEANONLY)) == 0 && 1301 (bo->bo_dirty.bv_cnt > 0 || bo->bo_clean.bv_cnt > 0)) 1302 panic("vinvalbuf: flush failed"); 1303 BO_UNLOCK(bo); 1304 #endif 1305 return (0); 1306 } 1307 1308 /* 1309 * Flush out and invalidate all buffers associated with a vnode. 1310 * Called with the underlying object locked. 1311 */ 1312 int 1313 vinvalbuf(struct vnode *vp, int flags, int slpflag, int slptimeo) 1314 { 1315 1316 CTR3(KTR_VFS, "%s: vp %p with flags %d", __func__, vp, flags); 1317 ASSERT_VOP_LOCKED(vp, "vinvalbuf"); 1318 if (vp->v_object != NULL && vp->v_object->handle != vp) 1319 return (0); 1320 return (bufobj_invalbuf(&vp->v_bufobj, flags, slpflag, slptimeo)); 1321 } 1322 1323 /* 1324 * Flush out buffers on the specified list. 1325 * 1326 */ 1327 static int 1328 flushbuflist(struct bufv *bufv, int flags, struct bufobj *bo, int slpflag, 1329 int slptimeo) 1330 { 1331 struct buf *bp, *nbp; 1332 int retval, error; 1333 daddr_t lblkno; 1334 b_xflags_t xflags; 1335 1336 ASSERT_BO_WLOCKED(bo); 1337 1338 retval = 0; 1339 TAILQ_FOREACH_SAFE(bp, &bufv->bv_hd, b_bobufs, nbp) { 1340 if (((flags & V_NORMAL) && (bp->b_xflags & BX_ALTDATA)) || 1341 ((flags & V_ALT) && (bp->b_xflags & BX_ALTDATA) == 0)) { 1342 continue; 1343 } 1344 lblkno = 0; 1345 xflags = 0; 1346 if (nbp != NULL) { 1347 lblkno = nbp->b_lblkno; 1348 xflags = nbp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN); 1349 } 1350 retval = EAGAIN; 1351 error = BUF_TIMELOCK(bp, 1352 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, BO_LOCKPTR(bo), 1353 "flushbuf", slpflag, slptimeo); 1354 if (error) { 1355 BO_LOCK(bo); 1356 return (error != ENOLCK ? error : EAGAIN); 1357 } 1358 KASSERT(bp->b_bufobj == bo, 1359 ("bp %p wrong b_bufobj %p should be %p", 1360 bp, bp->b_bufobj, bo)); 1361 if (bp->b_bufobj != bo) { /* XXX: necessary ? */ 1362 BUF_UNLOCK(bp); 1363 BO_LOCK(bo); 1364 return (EAGAIN); 1365 } 1366 /* 1367 * XXX Since there are no node locks for NFS, I 1368 * believe there is a slight chance that a delayed 1369 * write will occur while sleeping just above, so 1370 * check for it. 1371 */ 1372 if (((bp->b_flags & (B_DELWRI | B_INVAL)) == B_DELWRI) && 1373 (flags & V_SAVE)) { 1374 bremfree(bp); 1375 bp->b_flags |= B_ASYNC; 1376 bwrite(bp); 1377 BO_LOCK(bo); 1378 return (EAGAIN); /* XXX: why not loop ? */ 1379 } 1380 bremfree(bp); 1381 bp->b_flags |= (B_INVAL | B_RELBUF); 1382 bp->b_flags &= ~B_ASYNC; 1383 brelse(bp); 1384 BO_LOCK(bo); 1385 if (nbp != NULL && 1386 (nbp->b_bufobj != bo || 1387 nbp->b_lblkno != lblkno || 1388 (nbp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN)) != xflags)) 1389 break; /* nbp invalid */ 1390 } 1391 return (retval); 1392 } 1393 1394 /* 1395 * Truncate a file's buffer and pages to a specified length. This 1396 * is in lieu of the old vinvalbuf mechanism, which performed unneeded 1397 * sync activity. 1398 */ 1399 int 1400 vtruncbuf(struct vnode *vp, struct ucred *cred, off_t length, int blksize) 1401 { 1402 struct buf *bp, *nbp; 1403 int anyfreed; 1404 int trunclbn; 1405 struct bufobj *bo; 1406 1407 CTR5(KTR_VFS, "%s: vp %p with cred %p and block %d:%ju", __func__, 1408 vp, cred, blksize, (uintmax_t)length); 1409 1410 /* 1411 * Round up to the *next* lbn. 1412 */ 1413 trunclbn = (length + blksize - 1) / blksize; 1414 1415 ASSERT_VOP_LOCKED(vp, "vtruncbuf"); 1416 restart: 1417 bo = &vp->v_bufobj; 1418 BO_LOCK(bo); 1419 anyfreed = 1; 1420 for (;anyfreed;) { 1421 anyfreed = 0; 1422 TAILQ_FOREACH_SAFE(bp, &bo->bo_clean.bv_hd, b_bobufs, nbp) { 1423 if (bp->b_lblkno < trunclbn) 1424 continue; 1425 if (BUF_LOCK(bp, 1426 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, 1427 BO_LOCKPTR(bo)) == ENOLCK) 1428 goto restart; 1429 1430 bremfree(bp); 1431 bp->b_flags |= (B_INVAL | B_RELBUF); 1432 bp->b_flags &= ~B_ASYNC; 1433 brelse(bp); 1434 anyfreed = 1; 1435 1436 BO_LOCK(bo); 1437 if (nbp != NULL && 1438 (((nbp->b_xflags & BX_VNCLEAN) == 0) || 1439 (nbp->b_vp != vp) || 1440 (nbp->b_flags & B_DELWRI))) { 1441 BO_UNLOCK(bo); 1442 goto restart; 1443 } 1444 } 1445 1446 TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) { 1447 if (bp->b_lblkno < trunclbn) 1448 continue; 1449 if (BUF_LOCK(bp, 1450 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, 1451 BO_LOCKPTR(bo)) == ENOLCK) 1452 goto restart; 1453 bremfree(bp); 1454 bp->b_flags |= (B_INVAL | B_RELBUF); 1455 bp->b_flags &= ~B_ASYNC; 1456 brelse(bp); 1457 anyfreed = 1; 1458 1459 BO_LOCK(bo); 1460 if (nbp != NULL && 1461 (((nbp->b_xflags & BX_VNDIRTY) == 0) || 1462 (nbp->b_vp != vp) || 1463 (nbp->b_flags & B_DELWRI) == 0)) { 1464 BO_UNLOCK(bo); 1465 goto restart; 1466 } 1467 } 1468 } 1469 1470 if (length > 0) { 1471 restartsync: 1472 TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) { 1473 if (bp->b_lblkno > 0) 1474 continue; 1475 /* 1476 * Since we hold the vnode lock this should only 1477 * fail if we're racing with the buf daemon. 1478 */ 1479 if (BUF_LOCK(bp, 1480 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, 1481 BO_LOCKPTR(bo)) == ENOLCK) { 1482 goto restart; 1483 } 1484 VNASSERT((bp->b_flags & B_DELWRI), vp, 1485 ("buf(%p) on dirty queue without DELWRI", bp)); 1486 1487 bremfree(bp); 1488 bawrite(bp); 1489 BO_LOCK(bo); 1490 goto restartsync; 1491 } 1492 } 1493 1494 bufobj_wwait(bo, 0, 0); 1495 BO_UNLOCK(bo); 1496 vnode_pager_setsize(vp, length); 1497 1498 return (0); 1499 } 1500 1501 static void 1502 buf_vlist_remove(struct buf *bp) 1503 { 1504 struct bufv *bv; 1505 1506 KASSERT(bp->b_bufobj != NULL, ("No b_bufobj %p", bp)); 1507 ASSERT_BO_WLOCKED(bp->b_bufobj); 1508 KASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) != 1509 (BX_VNDIRTY|BX_VNCLEAN), 1510 ("buf_vlist_remove: Buf %p is on two lists", bp)); 1511 if (bp->b_xflags & BX_VNDIRTY) 1512 bv = &bp->b_bufobj->bo_dirty; 1513 else 1514 bv = &bp->b_bufobj->bo_clean; 1515 BUF_PCTRIE_REMOVE(&bv->bv_root, bp->b_lblkno); 1516 TAILQ_REMOVE(&bv->bv_hd, bp, b_bobufs); 1517 bv->bv_cnt--; 1518 bp->b_xflags &= ~(BX_VNDIRTY | BX_VNCLEAN); 1519 } 1520 1521 /* 1522 * Add the buffer to the sorted clean or dirty block list. 1523 * 1524 * NOTE: xflags is passed as a constant, optimizing this inline function! 1525 */ 1526 static void 1527 buf_vlist_add(struct buf *bp, struct bufobj *bo, b_xflags_t xflags) 1528 { 1529 struct bufv *bv; 1530 struct buf *n; 1531 int error; 1532 1533 ASSERT_BO_WLOCKED(bo); 1534 KASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) == 0, 1535 ("buf_vlist_add: Buf %p has existing xflags %d", bp, bp->b_xflags)); 1536 bp->b_xflags |= xflags; 1537 if (xflags & BX_VNDIRTY) 1538 bv = &bo->bo_dirty; 1539 else 1540 bv = &bo->bo_clean; 1541 1542 /* 1543 * Keep the list ordered. Optimize empty list insertion. Assume 1544 * we tend to grow at the tail so lookup_le should usually be cheaper 1545 * than _ge. 1546 */ 1547 if (bv->bv_cnt == 0 || 1548 bp->b_lblkno > TAILQ_LAST(&bv->bv_hd, buflists)->b_lblkno) 1549 TAILQ_INSERT_TAIL(&bv->bv_hd, bp, b_bobufs); 1550 else if ((n = BUF_PCTRIE_LOOKUP_LE(&bv->bv_root, bp->b_lblkno)) == NULL) 1551 TAILQ_INSERT_HEAD(&bv->bv_hd, bp, b_bobufs); 1552 else 1553 TAILQ_INSERT_AFTER(&bv->bv_hd, n, bp, b_bobufs); 1554 error = BUF_PCTRIE_INSERT(&bv->bv_root, bp); 1555 if (error) 1556 panic("buf_vlist_add: Preallocated nodes insufficient."); 1557 bv->bv_cnt++; 1558 } 1559 1560 /* 1561 * Lookup a buffer using the splay tree. Note that we specifically avoid 1562 * shadow buffers used in background bitmap writes. 1563 * 1564 * This code isn't quite efficient as it could be because we are maintaining 1565 * two sorted lists and do not know which list the block resides in. 1566 * 1567 * During a "make buildworld" the desired buffer is found at one of 1568 * the roots more than 60% of the time. Thus, checking both roots 1569 * before performing either splay eliminates unnecessary splays on the 1570 * first tree splayed. 1571 */ 1572 struct buf * 1573 gbincore(struct bufobj *bo, daddr_t lblkno) 1574 { 1575 struct buf *bp; 1576 1577 ASSERT_BO_LOCKED(bo); 1578 bp = BUF_PCTRIE_LOOKUP(&bo->bo_clean.bv_root, lblkno); 1579 if (bp != NULL) 1580 return (bp); 1581 return BUF_PCTRIE_LOOKUP(&bo->bo_dirty.bv_root, lblkno); 1582 } 1583 1584 /* 1585 * Associate a buffer with a vnode. 1586 */ 1587 void 1588 bgetvp(struct vnode *vp, struct buf *bp) 1589 { 1590 struct bufobj *bo; 1591 1592 bo = &vp->v_bufobj; 1593 ASSERT_BO_WLOCKED(bo); 1594 VNASSERT(bp->b_vp == NULL, bp->b_vp, ("bgetvp: not free")); 1595 1596 CTR3(KTR_BUF, "bgetvp(%p) vp %p flags %X", bp, vp, bp->b_flags); 1597 VNASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) == 0, vp, 1598 ("bgetvp: bp already attached! %p", bp)); 1599 1600 vhold(vp); 1601 bp->b_vp = vp; 1602 bp->b_bufobj = bo; 1603 /* 1604 * Insert onto list for new vnode. 1605 */ 1606 buf_vlist_add(bp, bo, BX_VNCLEAN); 1607 } 1608 1609 /* 1610 * Disassociate a buffer from a vnode. 1611 */ 1612 void 1613 brelvp(struct buf *bp) 1614 { 1615 struct bufobj *bo; 1616 struct vnode *vp; 1617 1618 CTR3(KTR_BUF, "brelvp(%p) vp %p flags %X", bp, bp->b_vp, bp->b_flags); 1619 KASSERT(bp->b_vp != NULL, ("brelvp: NULL")); 1620 1621 /* 1622 * Delete from old vnode list, if on one. 1623 */ 1624 vp = bp->b_vp; /* XXX */ 1625 bo = bp->b_bufobj; 1626 BO_LOCK(bo); 1627 if (bp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN)) 1628 buf_vlist_remove(bp); 1629 else 1630 panic("brelvp: Buffer %p not on queue.", bp); 1631 if ((bo->bo_flag & BO_ONWORKLST) && bo->bo_dirty.bv_cnt == 0) { 1632 bo->bo_flag &= ~BO_ONWORKLST; 1633 mtx_lock(&sync_mtx); 1634 LIST_REMOVE(bo, bo_synclist); 1635 syncer_worklist_len--; 1636 mtx_unlock(&sync_mtx); 1637 } 1638 bp->b_vp = NULL; 1639 bp->b_bufobj = NULL; 1640 BO_UNLOCK(bo); 1641 vdrop(vp); 1642 } 1643 1644 /* 1645 * Add an item to the syncer work queue. 1646 */ 1647 static void 1648 vn_syncer_add_to_worklist(struct bufobj *bo, int delay) 1649 { 1650 int slot; 1651 1652 ASSERT_BO_WLOCKED(bo); 1653 1654 mtx_lock(&sync_mtx); 1655 if (bo->bo_flag & BO_ONWORKLST) 1656 LIST_REMOVE(bo, bo_synclist); 1657 else { 1658 bo->bo_flag |= BO_ONWORKLST; 1659 syncer_worklist_len++; 1660 } 1661 1662 if (delay > syncer_maxdelay - 2) 1663 delay = syncer_maxdelay - 2; 1664 slot = (syncer_delayno + delay) & syncer_mask; 1665 1666 LIST_INSERT_HEAD(&syncer_workitem_pending[slot], bo, bo_synclist); 1667 mtx_unlock(&sync_mtx); 1668 } 1669 1670 static int 1671 sysctl_vfs_worklist_len(SYSCTL_HANDLER_ARGS) 1672 { 1673 int error, len; 1674 1675 mtx_lock(&sync_mtx); 1676 len = syncer_worklist_len - sync_vnode_count; 1677 mtx_unlock(&sync_mtx); 1678 error = SYSCTL_OUT(req, &len, sizeof(len)); 1679 return (error); 1680 } 1681 1682 SYSCTL_PROC(_vfs, OID_AUTO, worklist_len, CTLTYPE_INT | CTLFLAG_RD, NULL, 0, 1683 sysctl_vfs_worklist_len, "I", "Syncer thread worklist length"); 1684 1685 static struct proc *updateproc; 1686 static void sched_sync(void); 1687 static struct kproc_desc up_kp = { 1688 "syncer", 1689 sched_sync, 1690 &updateproc 1691 }; 1692 SYSINIT(syncer, SI_SUB_KTHREAD_UPDATE, SI_ORDER_FIRST, kproc_start, &up_kp); 1693 1694 static int 1695 sync_vnode(struct synclist *slp, struct bufobj **bo, struct thread *td) 1696 { 1697 struct vnode *vp; 1698 struct mount *mp; 1699 1700 *bo = LIST_FIRST(slp); 1701 if (*bo == NULL) 1702 return (0); 1703 vp = (*bo)->__bo_vnode; /* XXX */ 1704 if (VOP_ISLOCKED(vp) != 0 || VI_TRYLOCK(vp) == 0) 1705 return (1); 1706 /* 1707 * We use vhold in case the vnode does not 1708 * successfully sync. vhold prevents the vnode from 1709 * going away when we unlock the sync_mtx so that 1710 * we can acquire the vnode interlock. 1711 */ 1712 vholdl(vp); 1713 mtx_unlock(&sync_mtx); 1714 VI_UNLOCK(vp); 1715 if (vn_start_write(vp, &mp, V_NOWAIT) != 0) { 1716 vdrop(vp); 1717 mtx_lock(&sync_mtx); 1718 return (*bo == LIST_FIRST(slp)); 1719 } 1720 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 1721 (void) VOP_FSYNC(vp, MNT_LAZY, td); 1722 VOP_UNLOCK(vp, 0); 1723 vn_finished_write(mp); 1724 BO_LOCK(*bo); 1725 if (((*bo)->bo_flag & BO_ONWORKLST) != 0) { 1726 /* 1727 * Put us back on the worklist. The worklist 1728 * routine will remove us from our current 1729 * position and then add us back in at a later 1730 * position. 1731 */ 1732 vn_syncer_add_to_worklist(*bo, syncdelay); 1733 } 1734 BO_UNLOCK(*bo); 1735 vdrop(vp); 1736 mtx_lock(&sync_mtx); 1737 return (0); 1738 } 1739 1740 /* 1741 * System filesystem synchronizer daemon. 1742 */ 1743 static void 1744 sched_sync(void) 1745 { 1746 struct synclist *next, *slp; 1747 struct bufobj *bo; 1748 long starttime; 1749 struct thread *td = curthread; 1750 int last_work_seen; 1751 int net_worklist_len; 1752 int syncer_final_iter; 1753 int first_printf; 1754 int error; 1755 1756 last_work_seen = 0; 1757 syncer_final_iter = 0; 1758 first_printf = 1; 1759 syncer_state = SYNCER_RUNNING; 1760 starttime = time_uptime; 1761 td->td_pflags |= TDP_NORUNNINGBUF; 1762 1763 EVENTHANDLER_REGISTER(shutdown_pre_sync, syncer_shutdown, td->td_proc, 1764 SHUTDOWN_PRI_LAST); 1765 1766 mtx_lock(&sync_mtx); 1767 for (;;) { 1768 if (syncer_state == SYNCER_FINAL_DELAY && 1769 syncer_final_iter == 0) { 1770 mtx_unlock(&sync_mtx); 1771 kproc_suspend_check(td->td_proc); 1772 mtx_lock(&sync_mtx); 1773 } 1774 net_worklist_len = syncer_worklist_len - sync_vnode_count; 1775 if (syncer_state != SYNCER_RUNNING && 1776 starttime != time_uptime) { 1777 if (first_printf) { 1778 printf("\nSyncing disks, vnodes remaining..."); 1779 first_printf = 0; 1780 } 1781 printf("%d ", net_worklist_len); 1782 } 1783 starttime = time_uptime; 1784 1785 /* 1786 * Push files whose dirty time has expired. Be careful 1787 * of interrupt race on slp queue. 1788 * 1789 * Skip over empty worklist slots when shutting down. 1790 */ 1791 do { 1792 slp = &syncer_workitem_pending[syncer_delayno]; 1793 syncer_delayno += 1; 1794 if (syncer_delayno == syncer_maxdelay) 1795 syncer_delayno = 0; 1796 next = &syncer_workitem_pending[syncer_delayno]; 1797 /* 1798 * If the worklist has wrapped since the 1799 * it was emptied of all but syncer vnodes, 1800 * switch to the FINAL_DELAY state and run 1801 * for one more second. 1802 */ 1803 if (syncer_state == SYNCER_SHUTTING_DOWN && 1804 net_worklist_len == 0 && 1805 last_work_seen == syncer_delayno) { 1806 syncer_state = SYNCER_FINAL_DELAY; 1807 syncer_final_iter = SYNCER_SHUTDOWN_SPEEDUP; 1808 } 1809 } while (syncer_state != SYNCER_RUNNING && LIST_EMPTY(slp) && 1810 syncer_worklist_len > 0); 1811 1812 /* 1813 * Keep track of the last time there was anything 1814 * on the worklist other than syncer vnodes. 1815 * Return to the SHUTTING_DOWN state if any 1816 * new work appears. 1817 */ 1818 if (net_worklist_len > 0 || syncer_state == SYNCER_RUNNING) 1819 last_work_seen = syncer_delayno; 1820 if (net_worklist_len > 0 && syncer_state == SYNCER_FINAL_DELAY) 1821 syncer_state = SYNCER_SHUTTING_DOWN; 1822 while (!LIST_EMPTY(slp)) { 1823 error = sync_vnode(slp, &bo, td); 1824 if (error == 1) { 1825 LIST_REMOVE(bo, bo_synclist); 1826 LIST_INSERT_HEAD(next, bo, bo_synclist); 1827 continue; 1828 } 1829 1830 if (first_printf == 0) 1831 wdog_kern_pat(WD_LASTVAL); 1832 1833 } 1834 if (syncer_state == SYNCER_FINAL_DELAY && syncer_final_iter > 0) 1835 syncer_final_iter--; 1836 /* 1837 * The variable rushjob allows the kernel to speed up the 1838 * processing of the filesystem syncer process. A rushjob 1839 * value of N tells the filesystem syncer to process the next 1840 * N seconds worth of work on its queue ASAP. Currently rushjob 1841 * is used by the soft update code to speed up the filesystem 1842 * syncer process when the incore state is getting so far 1843 * ahead of the disk that the kernel memory pool is being 1844 * threatened with exhaustion. 1845 */ 1846 if (rushjob > 0) { 1847 rushjob -= 1; 1848 continue; 1849 } 1850 /* 1851 * Just sleep for a short period of time between 1852 * iterations when shutting down to allow some I/O 1853 * to happen. 1854 * 1855 * If it has taken us less than a second to process the 1856 * current work, then wait. Otherwise start right over 1857 * again. We can still lose time if any single round 1858 * takes more than two seconds, but it does not really 1859 * matter as we are just trying to generally pace the 1860 * filesystem activity. 1861 */ 1862 if (syncer_state != SYNCER_RUNNING || 1863 time_uptime == starttime) { 1864 thread_lock(td); 1865 sched_prio(td, PPAUSE); 1866 thread_unlock(td); 1867 } 1868 if (syncer_state != SYNCER_RUNNING) 1869 cv_timedwait(&sync_wakeup, &sync_mtx, 1870 hz / SYNCER_SHUTDOWN_SPEEDUP); 1871 else if (time_uptime == starttime) 1872 cv_timedwait(&sync_wakeup, &sync_mtx, hz); 1873 } 1874 } 1875 1876 /* 1877 * Request the syncer daemon to speed up its work. 1878 * We never push it to speed up more than half of its 1879 * normal turn time, otherwise it could take over the cpu. 1880 */ 1881 int 1882 speedup_syncer(void) 1883 { 1884 int ret = 0; 1885 1886 mtx_lock(&sync_mtx); 1887 if (rushjob < syncdelay / 2) { 1888 rushjob += 1; 1889 stat_rush_requests += 1; 1890 ret = 1; 1891 } 1892 mtx_unlock(&sync_mtx); 1893 cv_broadcast(&sync_wakeup); 1894 return (ret); 1895 } 1896 1897 /* 1898 * Tell the syncer to speed up its work and run though its work 1899 * list several times, then tell it to shut down. 1900 */ 1901 static void 1902 syncer_shutdown(void *arg, int howto) 1903 { 1904 1905 if (howto & RB_NOSYNC) 1906 return; 1907 mtx_lock(&sync_mtx); 1908 syncer_state = SYNCER_SHUTTING_DOWN; 1909 rushjob = 0; 1910 mtx_unlock(&sync_mtx); 1911 cv_broadcast(&sync_wakeup); 1912 kproc_shutdown(arg, howto); 1913 } 1914 1915 /* 1916 * Reassign a buffer from one vnode to another. 1917 * Used to assign file specific control information 1918 * (indirect blocks) to the vnode to which they belong. 1919 */ 1920 void 1921 reassignbuf(struct buf *bp) 1922 { 1923 struct vnode *vp; 1924 struct bufobj *bo; 1925 int delay; 1926 #ifdef INVARIANTS 1927 struct bufv *bv; 1928 #endif 1929 1930 vp = bp->b_vp; 1931 bo = bp->b_bufobj; 1932 ++reassignbufcalls; 1933 1934 CTR3(KTR_BUF, "reassignbuf(%p) vp %p flags %X", 1935 bp, bp->b_vp, bp->b_flags); 1936 /* 1937 * B_PAGING flagged buffers cannot be reassigned because their vp 1938 * is not fully linked in. 1939 */ 1940 if (bp->b_flags & B_PAGING) 1941 panic("cannot reassign paging buffer"); 1942 1943 /* 1944 * Delete from old vnode list, if on one. 1945 */ 1946 BO_LOCK(bo); 1947 if (bp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN)) 1948 buf_vlist_remove(bp); 1949 else 1950 panic("reassignbuf: Buffer %p not on queue.", bp); 1951 /* 1952 * If dirty, put on list of dirty buffers; otherwise insert onto list 1953 * of clean buffers. 1954 */ 1955 if (bp->b_flags & B_DELWRI) { 1956 if ((bo->bo_flag & BO_ONWORKLST) == 0) { 1957 switch (vp->v_type) { 1958 case VDIR: 1959 delay = dirdelay; 1960 break; 1961 case VCHR: 1962 delay = metadelay; 1963 break; 1964 default: 1965 delay = filedelay; 1966 } 1967 vn_syncer_add_to_worklist(bo, delay); 1968 } 1969 buf_vlist_add(bp, bo, BX_VNDIRTY); 1970 } else { 1971 buf_vlist_add(bp, bo, BX_VNCLEAN); 1972 1973 if ((bo->bo_flag & BO_ONWORKLST) && bo->bo_dirty.bv_cnt == 0) { 1974 mtx_lock(&sync_mtx); 1975 LIST_REMOVE(bo, bo_synclist); 1976 syncer_worklist_len--; 1977 mtx_unlock(&sync_mtx); 1978 bo->bo_flag &= ~BO_ONWORKLST; 1979 } 1980 } 1981 #ifdef INVARIANTS 1982 bv = &bo->bo_clean; 1983 bp = TAILQ_FIRST(&bv->bv_hd); 1984 KASSERT(bp == NULL || bp->b_bufobj == bo, 1985 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 1986 bp = TAILQ_LAST(&bv->bv_hd, buflists); 1987 KASSERT(bp == NULL || bp->b_bufobj == bo, 1988 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 1989 bv = &bo->bo_dirty; 1990 bp = TAILQ_FIRST(&bv->bv_hd); 1991 KASSERT(bp == NULL || bp->b_bufobj == bo, 1992 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 1993 bp = TAILQ_LAST(&bv->bv_hd, buflists); 1994 KASSERT(bp == NULL || bp->b_bufobj == bo, 1995 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 1996 #endif 1997 BO_UNLOCK(bo); 1998 } 1999 2000 /* 2001 * Increment the use and hold counts on the vnode, taking care to reference 2002 * the driver's usecount if this is a chardev. The vholdl() will remove 2003 * the vnode from the free list if it is presently free. Requires the 2004 * vnode interlock and returns with it held. 2005 */ 2006 static void 2007 v_incr_usecount(struct vnode *vp) 2008 { 2009 2010 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2011 vp->v_usecount++; 2012 if (vp->v_type == VCHR && vp->v_rdev != NULL) { 2013 dev_lock(); 2014 vp->v_rdev->si_usecount++; 2015 dev_unlock(); 2016 } 2017 vholdl(vp); 2018 } 2019 2020 /* 2021 * Turn a holdcnt into a use+holdcnt such that only one call to 2022 * v_decr_usecount is needed. 2023 */ 2024 static void 2025 v_upgrade_usecount(struct vnode *vp) 2026 { 2027 2028 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2029 vp->v_usecount++; 2030 if (vp->v_type == VCHR && vp->v_rdev != NULL) { 2031 dev_lock(); 2032 vp->v_rdev->si_usecount++; 2033 dev_unlock(); 2034 } 2035 } 2036 2037 /* 2038 * Decrement the vnode use and hold count along with the driver's usecount 2039 * if this is a chardev. The vdropl() below releases the vnode interlock 2040 * as it may free the vnode. 2041 */ 2042 static void 2043 v_decr_usecount(struct vnode *vp) 2044 { 2045 2046 ASSERT_VI_LOCKED(vp, __FUNCTION__); 2047 VNASSERT(vp->v_usecount > 0, vp, 2048 ("v_decr_usecount: negative usecount")); 2049 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2050 vp->v_usecount--; 2051 if (vp->v_type == VCHR && vp->v_rdev != NULL) { 2052 dev_lock(); 2053 vp->v_rdev->si_usecount--; 2054 dev_unlock(); 2055 } 2056 vdropl(vp); 2057 } 2058 2059 /* 2060 * Decrement only the use count and driver use count. This is intended to 2061 * be paired with a follow on vdropl() to release the remaining hold count. 2062 * In this way we may vgone() a vnode with a 0 usecount without risk of 2063 * having it end up on a free list because the hold count is kept above 0. 2064 */ 2065 static void 2066 v_decr_useonly(struct vnode *vp) 2067 { 2068 2069 ASSERT_VI_LOCKED(vp, __FUNCTION__); 2070 VNASSERT(vp->v_usecount > 0, vp, 2071 ("v_decr_useonly: negative usecount")); 2072 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2073 vp->v_usecount--; 2074 if (vp->v_type == VCHR && vp->v_rdev != NULL) { 2075 dev_lock(); 2076 vp->v_rdev->si_usecount--; 2077 dev_unlock(); 2078 } 2079 } 2080 2081 /* 2082 * Grab a particular vnode from the free list, increment its 2083 * reference count and lock it. VI_DOOMED is set if the vnode 2084 * is being destroyed. Only callers who specify LK_RETRY will 2085 * see doomed vnodes. If inactive processing was delayed in 2086 * vput try to do it here. 2087 */ 2088 int 2089 vget(struct vnode *vp, int flags, struct thread *td) 2090 { 2091 int error; 2092 2093 error = 0; 2094 VNASSERT((flags & LK_TYPE_MASK) != 0, vp, 2095 ("vget: invalid lock operation")); 2096 CTR3(KTR_VFS, "%s: vp %p with flags %d", __func__, vp, flags); 2097 2098 if ((flags & LK_INTERLOCK) == 0) 2099 VI_LOCK(vp); 2100 vholdl(vp); 2101 if ((error = vn_lock(vp, flags | LK_INTERLOCK)) != 0) { 2102 vdrop(vp); 2103 CTR2(KTR_VFS, "%s: impossible to lock vnode %p", __func__, 2104 vp); 2105 return (error); 2106 } 2107 if (vp->v_iflag & VI_DOOMED && (flags & LK_RETRY) == 0) 2108 panic("vget: vn_lock failed to return ENOENT\n"); 2109 VI_LOCK(vp); 2110 /* Upgrade our holdcnt to a usecount. */ 2111 v_upgrade_usecount(vp); 2112 /* 2113 * We don't guarantee that any particular close will 2114 * trigger inactive processing so just make a best effort 2115 * here at preventing a reference to a removed file. If 2116 * we don't succeed no harm is done. 2117 */ 2118 if (vp->v_iflag & VI_OWEINACT) { 2119 if (VOP_ISLOCKED(vp) == LK_EXCLUSIVE && 2120 (flags & LK_NOWAIT) == 0) 2121 vinactive(vp, td); 2122 vp->v_iflag &= ~VI_OWEINACT; 2123 } 2124 VI_UNLOCK(vp); 2125 return (0); 2126 } 2127 2128 /* 2129 * Increase the reference count of a vnode. 2130 */ 2131 void 2132 vref(struct vnode *vp) 2133 { 2134 2135 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2136 VI_LOCK(vp); 2137 v_incr_usecount(vp); 2138 VI_UNLOCK(vp); 2139 } 2140 2141 /* 2142 * Return reference count of a vnode. 2143 * 2144 * The results of this call are only guaranteed when some mechanism other 2145 * than the VI lock is used to stop other processes from gaining references 2146 * to the vnode. This may be the case if the caller holds the only reference. 2147 * This is also useful when stale data is acceptable as race conditions may 2148 * be accounted for by some other means. 2149 */ 2150 int 2151 vrefcnt(struct vnode *vp) 2152 { 2153 int usecnt; 2154 2155 VI_LOCK(vp); 2156 usecnt = vp->v_usecount; 2157 VI_UNLOCK(vp); 2158 2159 return (usecnt); 2160 } 2161 2162 #define VPUTX_VRELE 1 2163 #define VPUTX_VPUT 2 2164 #define VPUTX_VUNREF 3 2165 2166 static void 2167 vputx(struct vnode *vp, int func) 2168 { 2169 int error; 2170 2171 KASSERT(vp != NULL, ("vputx: null vp")); 2172 if (func == VPUTX_VUNREF) 2173 ASSERT_VOP_LOCKED(vp, "vunref"); 2174 else if (func == VPUTX_VPUT) 2175 ASSERT_VOP_LOCKED(vp, "vput"); 2176 else 2177 KASSERT(func == VPUTX_VRELE, ("vputx: wrong func")); 2178 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2179 VI_LOCK(vp); 2180 2181 /* Skip this v_writecount check if we're going to panic below. */ 2182 VNASSERT(vp->v_writecount < vp->v_usecount || vp->v_usecount < 1, vp, 2183 ("vputx: missed vn_close")); 2184 error = 0; 2185 2186 if (vp->v_usecount > 1 || ((vp->v_iflag & VI_DOINGINACT) && 2187 vp->v_usecount == 1)) { 2188 if (func == VPUTX_VPUT) 2189 VOP_UNLOCK(vp, 0); 2190 v_decr_usecount(vp); 2191 return; 2192 } 2193 2194 if (vp->v_usecount != 1) { 2195 vprint("vputx: negative ref count", vp); 2196 panic("vputx: negative ref cnt"); 2197 } 2198 CTR2(KTR_VFS, "%s: return vnode %p to the freelist", __func__, vp); 2199 /* 2200 * We want to hold the vnode until the inactive finishes to 2201 * prevent vgone() races. We drop the use count here and the 2202 * hold count below when we're done. 2203 */ 2204 v_decr_useonly(vp); 2205 /* 2206 * We must call VOP_INACTIVE with the node locked. Mark 2207 * as VI_DOINGINACT to avoid recursion. 2208 */ 2209 vp->v_iflag |= VI_OWEINACT; 2210 switch (func) { 2211 case VPUTX_VRELE: 2212 error = vn_lock(vp, LK_EXCLUSIVE | LK_INTERLOCK); 2213 VI_LOCK(vp); 2214 break; 2215 case VPUTX_VPUT: 2216 if (VOP_ISLOCKED(vp) != LK_EXCLUSIVE) { 2217 error = VOP_LOCK(vp, LK_UPGRADE | LK_INTERLOCK | 2218 LK_NOWAIT); 2219 VI_LOCK(vp); 2220 } 2221 break; 2222 case VPUTX_VUNREF: 2223 if (VOP_ISLOCKED(vp) != LK_EXCLUSIVE) { 2224 error = VOP_LOCK(vp, LK_TRYUPGRADE | LK_INTERLOCK); 2225 VI_LOCK(vp); 2226 } 2227 break; 2228 } 2229 if (vp->v_usecount > 0) 2230 vp->v_iflag &= ~VI_OWEINACT; 2231 if (error == 0) { 2232 if (vp->v_iflag & VI_OWEINACT) 2233 vinactive(vp, curthread); 2234 if (func != VPUTX_VUNREF) 2235 VOP_UNLOCK(vp, 0); 2236 } 2237 vdropl(vp); 2238 } 2239 2240 /* 2241 * Vnode put/release. 2242 * If count drops to zero, call inactive routine and return to freelist. 2243 */ 2244 void 2245 vrele(struct vnode *vp) 2246 { 2247 2248 vputx(vp, VPUTX_VRELE); 2249 } 2250 2251 /* 2252 * Release an already locked vnode. This give the same effects as 2253 * unlock+vrele(), but takes less time and avoids releasing and 2254 * re-aquiring the lock (as vrele() acquires the lock internally.) 2255 */ 2256 void 2257 vput(struct vnode *vp) 2258 { 2259 2260 vputx(vp, VPUTX_VPUT); 2261 } 2262 2263 /* 2264 * Release an exclusively locked vnode. Do not unlock the vnode lock. 2265 */ 2266 void 2267 vunref(struct vnode *vp) 2268 { 2269 2270 vputx(vp, VPUTX_VUNREF); 2271 } 2272 2273 /* 2274 * Somebody doesn't want the vnode recycled. 2275 */ 2276 void 2277 vhold(struct vnode *vp) 2278 { 2279 2280 VI_LOCK(vp); 2281 vholdl(vp); 2282 VI_UNLOCK(vp); 2283 } 2284 2285 /* 2286 * Increase the hold count and activate if this is the first reference. 2287 */ 2288 void 2289 vholdl(struct vnode *vp) 2290 { 2291 struct mount *mp; 2292 2293 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2294 vp->v_holdcnt++; 2295 if (!VSHOULDBUSY(vp)) 2296 return; 2297 ASSERT_VI_LOCKED(vp, "vholdl"); 2298 VNASSERT((vp->v_iflag & VI_FREE) != 0, vp, ("vnode not free")); 2299 VNASSERT(vp->v_op != NULL, vp, ("vholdl: vnode already reclaimed.")); 2300 /* 2301 * Remove a vnode from the free list, mark it as in use, 2302 * and put it on the active list. 2303 */ 2304 mtx_lock(&vnode_free_list_mtx); 2305 TAILQ_REMOVE(&vnode_free_list, vp, v_actfreelist); 2306 freevnodes--; 2307 vp->v_iflag &= ~(VI_FREE|VI_AGE); 2308 KASSERT((vp->v_iflag & VI_ACTIVE) == 0, 2309 ("Activating already active vnode")); 2310 vp->v_iflag |= VI_ACTIVE; 2311 mp = vp->v_mount; 2312 TAILQ_INSERT_HEAD(&mp->mnt_activevnodelist, vp, v_actfreelist); 2313 mp->mnt_activevnodelistsize++; 2314 mtx_unlock(&vnode_free_list_mtx); 2315 } 2316 2317 /* 2318 * Note that there is one less who cares about this vnode. 2319 * vdrop() is the opposite of vhold(). 2320 */ 2321 void 2322 vdrop(struct vnode *vp) 2323 { 2324 2325 VI_LOCK(vp); 2326 vdropl(vp); 2327 } 2328 2329 /* 2330 * Drop the hold count of the vnode. If this is the last reference to 2331 * the vnode we place it on the free list unless it has been vgone'd 2332 * (marked VI_DOOMED) in which case we will free it. 2333 */ 2334 void 2335 vdropl(struct vnode *vp) 2336 { 2337 struct bufobj *bo; 2338 struct mount *mp; 2339 int active; 2340 2341 ASSERT_VI_LOCKED(vp, "vdropl"); 2342 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2343 if (vp->v_holdcnt <= 0) 2344 panic("vdrop: holdcnt %d", vp->v_holdcnt); 2345 vp->v_holdcnt--; 2346 VNASSERT(vp->v_holdcnt >= vp->v_usecount, vp, 2347 ("hold count less than use count")); 2348 if (vp->v_holdcnt > 0) { 2349 VI_UNLOCK(vp); 2350 return; 2351 } 2352 if ((vp->v_iflag & VI_DOOMED) == 0) { 2353 /* 2354 * Mark a vnode as free: remove it from its active list 2355 * and put it up for recycling on the freelist. 2356 */ 2357 VNASSERT(vp->v_op != NULL, vp, 2358 ("vdropl: vnode already reclaimed.")); 2359 VNASSERT((vp->v_iflag & VI_FREE) == 0, vp, 2360 ("vnode already free")); 2361 VNASSERT(VSHOULDFREE(vp), vp, 2362 ("vdropl: freeing when we shouldn't")); 2363 active = vp->v_iflag & VI_ACTIVE; 2364 vp->v_iflag &= ~VI_ACTIVE; 2365 mp = vp->v_mount; 2366 mtx_lock(&vnode_free_list_mtx); 2367 if (active) { 2368 TAILQ_REMOVE(&mp->mnt_activevnodelist, vp, 2369 v_actfreelist); 2370 mp->mnt_activevnodelistsize--; 2371 } 2372 if (vp->v_iflag & VI_AGE) { 2373 TAILQ_INSERT_HEAD(&vnode_free_list, vp, v_actfreelist); 2374 } else { 2375 TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_actfreelist); 2376 } 2377 freevnodes++; 2378 vp->v_iflag &= ~VI_AGE; 2379 vp->v_iflag |= VI_FREE; 2380 mtx_unlock(&vnode_free_list_mtx); 2381 VI_UNLOCK(vp); 2382 return; 2383 } 2384 /* 2385 * The vnode has been marked for destruction, so free it. 2386 */ 2387 CTR2(KTR_VFS, "%s: destroying the vnode %p", __func__, vp); 2388 mtx_lock(&vnode_free_list_mtx); 2389 numvnodes--; 2390 mtx_unlock(&vnode_free_list_mtx); 2391 bo = &vp->v_bufobj; 2392 VNASSERT((vp->v_iflag & VI_FREE) == 0, vp, 2393 ("cleaned vnode still on the free list.")); 2394 VNASSERT(vp->v_data == NULL, vp, ("cleaned vnode isn't")); 2395 VNASSERT(vp->v_holdcnt == 0, vp, ("Non-zero hold count")); 2396 VNASSERT(vp->v_usecount == 0, vp, ("Non-zero use count")); 2397 VNASSERT(vp->v_writecount == 0, vp, ("Non-zero write count")); 2398 VNASSERT(bo->bo_numoutput == 0, vp, ("Clean vnode has pending I/O's")); 2399 VNASSERT(bo->bo_clean.bv_cnt == 0, vp, ("cleanbufcnt not 0")); 2400 VNASSERT(pctrie_is_empty(&bo->bo_clean.bv_root), vp, 2401 ("clean blk trie not empty")); 2402 VNASSERT(bo->bo_dirty.bv_cnt == 0, vp, ("dirtybufcnt not 0")); 2403 VNASSERT(pctrie_is_empty(&bo->bo_dirty.bv_root), vp, 2404 ("dirty blk trie not empty")); 2405 VNASSERT(TAILQ_EMPTY(&vp->v_cache_dst), vp, ("vp has namecache dst")); 2406 VNASSERT(LIST_EMPTY(&vp->v_cache_src), vp, ("vp has namecache src")); 2407 VNASSERT(vp->v_cache_dd == NULL, vp, ("vp has namecache for ..")); 2408 VI_UNLOCK(vp); 2409 #ifdef MAC 2410 mac_vnode_destroy(vp); 2411 #endif 2412 if (vp->v_pollinfo != NULL) 2413 destroy_vpollinfo(vp->v_pollinfo); 2414 #ifdef INVARIANTS 2415 /* XXX Elsewhere we detect an already freed vnode via NULL v_op. */ 2416 vp->v_op = NULL; 2417 #endif 2418 rangelock_destroy(&vp->v_rl); 2419 lockdestroy(vp->v_vnlock); 2420 mtx_destroy(&vp->v_interlock); 2421 rw_destroy(BO_LOCKPTR(bo)); 2422 uma_zfree(vnode_zone, vp); 2423 } 2424 2425 /* 2426 * Call VOP_INACTIVE on the vnode and manage the DOINGINACT and OWEINACT 2427 * flags. DOINGINACT prevents us from recursing in calls to vinactive. 2428 * OWEINACT tracks whether a vnode missed a call to inactive due to a 2429 * failed lock upgrade. 2430 */ 2431 void 2432 vinactive(struct vnode *vp, struct thread *td) 2433 { 2434 struct vm_object *obj; 2435 2436 ASSERT_VOP_ELOCKED(vp, "vinactive"); 2437 ASSERT_VI_LOCKED(vp, "vinactive"); 2438 VNASSERT((vp->v_iflag & VI_DOINGINACT) == 0, vp, 2439 ("vinactive: recursed on VI_DOINGINACT")); 2440 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2441 vp->v_iflag |= VI_DOINGINACT; 2442 vp->v_iflag &= ~VI_OWEINACT; 2443 VI_UNLOCK(vp); 2444 /* 2445 * Before moving off the active list, we must be sure that any 2446 * modified pages are on the vnode's dirty list since these will 2447 * no longer be checked once the vnode is on the inactive list. 2448 * Because the vnode vm object keeps a hold reference on the vnode 2449 * if there is at least one resident non-cached page, the vnode 2450 * cannot leave the active list without the page cleanup done. 2451 */ 2452 obj = vp->v_object; 2453 if (obj != NULL && (obj->flags & OBJ_MIGHTBEDIRTY) != 0) { 2454 VM_OBJECT_WLOCK(obj); 2455 vm_object_page_clean(obj, 0, 0, OBJPC_NOSYNC); 2456 VM_OBJECT_WUNLOCK(obj); 2457 } 2458 VOP_INACTIVE(vp, td); 2459 VI_LOCK(vp); 2460 VNASSERT(vp->v_iflag & VI_DOINGINACT, vp, 2461 ("vinactive: lost VI_DOINGINACT")); 2462 vp->v_iflag &= ~VI_DOINGINACT; 2463 } 2464 2465 /* 2466 * Remove any vnodes in the vnode table belonging to mount point mp. 2467 * 2468 * If FORCECLOSE is not specified, there should not be any active ones, 2469 * return error if any are found (nb: this is a user error, not a 2470 * system error). If FORCECLOSE is specified, detach any active vnodes 2471 * that are found. 2472 * 2473 * If WRITECLOSE is set, only flush out regular file vnodes open for 2474 * writing. 2475 * 2476 * SKIPSYSTEM causes any vnodes marked VV_SYSTEM to be skipped. 2477 * 2478 * `rootrefs' specifies the base reference count for the root vnode 2479 * of this filesystem. The root vnode is considered busy if its 2480 * v_usecount exceeds this value. On a successful return, vflush(, td) 2481 * will call vrele() on the root vnode exactly rootrefs times. 2482 * If the SKIPSYSTEM or WRITECLOSE flags are specified, rootrefs must 2483 * be zero. 2484 */ 2485 #ifdef DIAGNOSTIC 2486 static int busyprt = 0; /* print out busy vnodes */ 2487 SYSCTL_INT(_debug, OID_AUTO, busyprt, CTLFLAG_RW, &busyprt, 0, "Print out busy vnodes"); 2488 #endif 2489 2490 int 2491 vflush(struct mount *mp, int rootrefs, int flags, struct thread *td) 2492 { 2493 struct vnode *vp, *mvp, *rootvp = NULL; 2494 struct vattr vattr; 2495 int busy = 0, error; 2496 2497 CTR4(KTR_VFS, "%s: mp %p with rootrefs %d and flags %d", __func__, mp, 2498 rootrefs, flags); 2499 if (rootrefs > 0) { 2500 KASSERT((flags & (SKIPSYSTEM | WRITECLOSE)) == 0, 2501 ("vflush: bad args")); 2502 /* 2503 * Get the filesystem root vnode. We can vput() it 2504 * immediately, since with rootrefs > 0, it won't go away. 2505 */ 2506 if ((error = VFS_ROOT(mp, LK_EXCLUSIVE, &rootvp)) != 0) { 2507 CTR2(KTR_VFS, "%s: vfs_root lookup failed with %d", 2508 __func__, error); 2509 return (error); 2510 } 2511 vput(rootvp); 2512 } 2513 loop: 2514 MNT_VNODE_FOREACH_ALL(vp, mp, mvp) { 2515 vholdl(vp); 2516 error = vn_lock(vp, LK_INTERLOCK | LK_EXCLUSIVE); 2517 if (error) { 2518 vdrop(vp); 2519 MNT_VNODE_FOREACH_ALL_ABORT(mp, mvp); 2520 goto loop; 2521 } 2522 /* 2523 * Skip over a vnodes marked VV_SYSTEM. 2524 */ 2525 if ((flags & SKIPSYSTEM) && (vp->v_vflag & VV_SYSTEM)) { 2526 VOP_UNLOCK(vp, 0); 2527 vdrop(vp); 2528 continue; 2529 } 2530 /* 2531 * If WRITECLOSE is set, flush out unlinked but still open 2532 * files (even if open only for reading) and regular file 2533 * vnodes open for writing. 2534 */ 2535 if (flags & WRITECLOSE) { 2536 if (vp->v_object != NULL) { 2537 VM_OBJECT_WLOCK(vp->v_object); 2538 vm_object_page_clean(vp->v_object, 0, 0, 0); 2539 VM_OBJECT_WUNLOCK(vp->v_object); 2540 } 2541 error = VOP_FSYNC(vp, MNT_WAIT, td); 2542 if (error != 0) { 2543 VOP_UNLOCK(vp, 0); 2544 vdrop(vp); 2545 MNT_VNODE_FOREACH_ALL_ABORT(mp, mvp); 2546 return (error); 2547 } 2548 error = VOP_GETATTR(vp, &vattr, td->td_ucred); 2549 VI_LOCK(vp); 2550 2551 if ((vp->v_type == VNON || 2552 (error == 0 && vattr.va_nlink > 0)) && 2553 (vp->v_writecount == 0 || vp->v_type != VREG)) { 2554 VOP_UNLOCK(vp, 0); 2555 vdropl(vp); 2556 continue; 2557 } 2558 } else 2559 VI_LOCK(vp); 2560 /* 2561 * With v_usecount == 0, all we need to do is clear out the 2562 * vnode data structures and we are done. 2563 * 2564 * If FORCECLOSE is set, forcibly close the vnode. 2565 */ 2566 if (vp->v_usecount == 0 || (flags & FORCECLOSE)) { 2567 VNASSERT(vp->v_usecount == 0 || 2568 (vp->v_type != VCHR && vp->v_type != VBLK), vp, 2569 ("device VNODE %p is FORCECLOSED", vp)); 2570 vgonel(vp); 2571 } else { 2572 busy++; 2573 #ifdef DIAGNOSTIC 2574 if (busyprt) 2575 vprint("vflush: busy vnode", vp); 2576 #endif 2577 } 2578 VOP_UNLOCK(vp, 0); 2579 vdropl(vp); 2580 } 2581 if (rootrefs > 0 && (flags & FORCECLOSE) == 0) { 2582 /* 2583 * If just the root vnode is busy, and if its refcount 2584 * is equal to `rootrefs', then go ahead and kill it. 2585 */ 2586 VI_LOCK(rootvp); 2587 KASSERT(busy > 0, ("vflush: not busy")); 2588 VNASSERT(rootvp->v_usecount >= rootrefs, rootvp, 2589 ("vflush: usecount %d < rootrefs %d", 2590 rootvp->v_usecount, rootrefs)); 2591 if (busy == 1 && rootvp->v_usecount == rootrefs) { 2592 VOP_LOCK(rootvp, LK_EXCLUSIVE|LK_INTERLOCK); 2593 vgone(rootvp); 2594 VOP_UNLOCK(rootvp, 0); 2595 busy = 0; 2596 } else 2597 VI_UNLOCK(rootvp); 2598 } 2599 if (busy) { 2600 CTR2(KTR_VFS, "%s: failing as %d vnodes are busy", __func__, 2601 busy); 2602 return (EBUSY); 2603 } 2604 for (; rootrefs > 0; rootrefs--) 2605 vrele(rootvp); 2606 return (0); 2607 } 2608 2609 /* 2610 * Recycle an unused vnode to the front of the free list. 2611 */ 2612 int 2613 vrecycle(struct vnode *vp) 2614 { 2615 int recycled; 2616 2617 ASSERT_VOP_ELOCKED(vp, "vrecycle"); 2618 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2619 recycled = 0; 2620 VI_LOCK(vp); 2621 if (vp->v_usecount == 0) { 2622 recycled = 1; 2623 vgonel(vp); 2624 } 2625 VI_UNLOCK(vp); 2626 return (recycled); 2627 } 2628 2629 /* 2630 * Eliminate all activity associated with a vnode 2631 * in preparation for reuse. 2632 */ 2633 void 2634 vgone(struct vnode *vp) 2635 { 2636 VI_LOCK(vp); 2637 vgonel(vp); 2638 VI_UNLOCK(vp); 2639 } 2640 2641 static void 2642 notify_lowervp_vfs_dummy(struct mount *mp __unused, 2643 struct vnode *lowervp __unused) 2644 { 2645 } 2646 2647 /* 2648 * Notify upper mounts about reclaimed or unlinked vnode. 2649 */ 2650 void 2651 vfs_notify_upper(struct vnode *vp, int event) 2652 { 2653 static struct vfsops vgonel_vfsops = { 2654 .vfs_reclaim_lowervp = notify_lowervp_vfs_dummy, 2655 .vfs_unlink_lowervp = notify_lowervp_vfs_dummy, 2656 }; 2657 struct mount *mp, *ump, *mmp; 2658 2659 mp = vp->v_mount; 2660 if (mp == NULL) 2661 return; 2662 2663 MNT_ILOCK(mp); 2664 if (TAILQ_EMPTY(&mp->mnt_uppers)) 2665 goto unlock; 2666 MNT_IUNLOCK(mp); 2667 mmp = malloc(sizeof(struct mount), M_TEMP, M_WAITOK | M_ZERO); 2668 mmp->mnt_op = &vgonel_vfsops; 2669 mmp->mnt_kern_flag |= MNTK_MARKER; 2670 MNT_ILOCK(mp); 2671 mp->mnt_kern_flag |= MNTK_VGONE_UPPER; 2672 for (ump = TAILQ_FIRST(&mp->mnt_uppers); ump != NULL;) { 2673 if ((ump->mnt_kern_flag & MNTK_MARKER) != 0) { 2674 ump = TAILQ_NEXT(ump, mnt_upper_link); 2675 continue; 2676 } 2677 TAILQ_INSERT_AFTER(&mp->mnt_uppers, ump, mmp, mnt_upper_link); 2678 MNT_IUNLOCK(mp); 2679 switch (event) { 2680 case VFS_NOTIFY_UPPER_RECLAIM: 2681 VFS_RECLAIM_LOWERVP(ump, vp); 2682 break; 2683 case VFS_NOTIFY_UPPER_UNLINK: 2684 VFS_UNLINK_LOWERVP(ump, vp); 2685 break; 2686 default: 2687 KASSERT(0, ("invalid event %d", event)); 2688 break; 2689 } 2690 MNT_ILOCK(mp); 2691 ump = TAILQ_NEXT(mmp, mnt_upper_link); 2692 TAILQ_REMOVE(&mp->mnt_uppers, mmp, mnt_upper_link); 2693 } 2694 free(mmp, M_TEMP); 2695 mp->mnt_kern_flag &= ~MNTK_VGONE_UPPER; 2696 if ((mp->mnt_kern_flag & MNTK_VGONE_WAITER) != 0) { 2697 mp->mnt_kern_flag &= ~MNTK_VGONE_WAITER; 2698 wakeup(&mp->mnt_uppers); 2699 } 2700 unlock: 2701 MNT_IUNLOCK(mp); 2702 } 2703 2704 /* 2705 * vgone, with the vp interlock held. 2706 */ 2707 void 2708 vgonel(struct vnode *vp) 2709 { 2710 struct thread *td; 2711 int oweinact; 2712 int active; 2713 struct mount *mp; 2714 2715 ASSERT_VOP_ELOCKED(vp, "vgonel"); 2716 ASSERT_VI_LOCKED(vp, "vgonel"); 2717 VNASSERT(vp->v_holdcnt, vp, 2718 ("vgonel: vp %p has no reference.", vp)); 2719 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2720 td = curthread; 2721 2722 /* 2723 * Don't vgonel if we're already doomed. 2724 */ 2725 if (vp->v_iflag & VI_DOOMED) 2726 return; 2727 vp->v_iflag |= VI_DOOMED; 2728 2729 /* 2730 * Check to see if the vnode is in use. If so, we have to call 2731 * VOP_CLOSE() and VOP_INACTIVE(). 2732 */ 2733 active = vp->v_usecount; 2734 oweinact = (vp->v_iflag & VI_OWEINACT); 2735 VI_UNLOCK(vp); 2736 vfs_notify_upper(vp, VFS_NOTIFY_UPPER_RECLAIM); 2737 2738 /* 2739 * Clean out any buffers associated with the vnode. 2740 * If the flush fails, just toss the buffers. 2741 */ 2742 mp = NULL; 2743 if (!TAILQ_EMPTY(&vp->v_bufobj.bo_dirty.bv_hd)) 2744 (void) vn_start_secondary_write(vp, &mp, V_WAIT); 2745 if (vinvalbuf(vp, V_SAVE, 0, 0) != 0) 2746 vinvalbuf(vp, 0, 0, 0); 2747 2748 /* 2749 * If purging an active vnode, it must be closed and 2750 * deactivated before being reclaimed. 2751 */ 2752 if (active) 2753 VOP_CLOSE(vp, FNONBLOCK, NOCRED, td); 2754 if (oweinact || active) { 2755 VI_LOCK(vp); 2756 if ((vp->v_iflag & VI_DOINGINACT) == 0) 2757 vinactive(vp, td); 2758 VI_UNLOCK(vp); 2759 } 2760 if (vp->v_type == VSOCK) 2761 vfs_unp_reclaim(vp); 2762 /* 2763 * Reclaim the vnode. 2764 */ 2765 if (VOP_RECLAIM(vp, td)) 2766 panic("vgone: cannot reclaim"); 2767 if (mp != NULL) 2768 vn_finished_secondary_write(mp); 2769 VNASSERT(vp->v_object == NULL, vp, 2770 ("vop_reclaim left v_object vp=%p, tag=%s", vp, vp->v_tag)); 2771 /* 2772 * Clear the advisory locks and wake up waiting threads. 2773 */ 2774 (void)VOP_ADVLOCKPURGE(vp); 2775 /* 2776 * Delete from old mount point vnode list. 2777 */ 2778 delmntque(vp); 2779 cache_purge(vp); 2780 /* 2781 * Done with purge, reset to the standard lock and invalidate 2782 * the vnode. 2783 */ 2784 VI_LOCK(vp); 2785 vp->v_vnlock = &vp->v_lock; 2786 vp->v_op = &dead_vnodeops; 2787 vp->v_tag = "none"; 2788 vp->v_type = VBAD; 2789 } 2790 2791 /* 2792 * Calculate the total number of references to a special device. 2793 */ 2794 int 2795 vcount(struct vnode *vp) 2796 { 2797 int count; 2798 2799 dev_lock(); 2800 count = vp->v_rdev->si_usecount; 2801 dev_unlock(); 2802 return (count); 2803 } 2804 2805 /* 2806 * Same as above, but using the struct cdev *as argument 2807 */ 2808 int 2809 count_dev(struct cdev *dev) 2810 { 2811 int count; 2812 2813 dev_lock(); 2814 count = dev->si_usecount; 2815 dev_unlock(); 2816 return(count); 2817 } 2818 2819 /* 2820 * Print out a description of a vnode. 2821 */ 2822 static char *typename[] = 2823 {"VNON", "VREG", "VDIR", "VBLK", "VCHR", "VLNK", "VSOCK", "VFIFO", "VBAD", 2824 "VMARKER"}; 2825 2826 void 2827 vn_printf(struct vnode *vp, const char *fmt, ...) 2828 { 2829 va_list ap; 2830 char buf[256], buf2[16]; 2831 u_long flags; 2832 2833 va_start(ap, fmt); 2834 vprintf(fmt, ap); 2835 va_end(ap); 2836 printf("%p: ", (void *)vp); 2837 printf("tag %s, type %s\n", vp->v_tag, typename[vp->v_type]); 2838 printf(" usecount %d, writecount %d, refcount %d mountedhere %p\n", 2839 vp->v_usecount, vp->v_writecount, vp->v_holdcnt, vp->v_mountedhere); 2840 buf[0] = '\0'; 2841 buf[1] = '\0'; 2842 if (vp->v_vflag & VV_ROOT) 2843 strlcat(buf, "|VV_ROOT", sizeof(buf)); 2844 if (vp->v_vflag & VV_ISTTY) 2845 strlcat(buf, "|VV_ISTTY", sizeof(buf)); 2846 if (vp->v_vflag & VV_NOSYNC) 2847 strlcat(buf, "|VV_NOSYNC", sizeof(buf)); 2848 if (vp->v_vflag & VV_ETERNALDEV) 2849 strlcat(buf, "|VV_ETERNALDEV", sizeof(buf)); 2850 if (vp->v_vflag & VV_CACHEDLABEL) 2851 strlcat(buf, "|VV_CACHEDLABEL", sizeof(buf)); 2852 if (vp->v_vflag & VV_TEXT) 2853 strlcat(buf, "|VV_TEXT", sizeof(buf)); 2854 if (vp->v_vflag & VV_COPYONWRITE) 2855 strlcat(buf, "|VV_COPYONWRITE", sizeof(buf)); 2856 if (vp->v_vflag & VV_SYSTEM) 2857 strlcat(buf, "|VV_SYSTEM", sizeof(buf)); 2858 if (vp->v_vflag & VV_PROCDEP) 2859 strlcat(buf, "|VV_PROCDEP", sizeof(buf)); 2860 if (vp->v_vflag & VV_NOKNOTE) 2861 strlcat(buf, "|VV_NOKNOTE", sizeof(buf)); 2862 if (vp->v_vflag & VV_DELETED) 2863 strlcat(buf, "|VV_DELETED", sizeof(buf)); 2864 if (vp->v_vflag & VV_MD) 2865 strlcat(buf, "|VV_MD", sizeof(buf)); 2866 if (vp->v_vflag & VV_FORCEINSMQ) 2867 strlcat(buf, "|VV_FORCEINSMQ", sizeof(buf)); 2868 flags = vp->v_vflag & ~(VV_ROOT | VV_ISTTY | VV_NOSYNC | VV_ETERNALDEV | 2869 VV_CACHEDLABEL | VV_TEXT | VV_COPYONWRITE | VV_SYSTEM | VV_PROCDEP | 2870 VV_NOKNOTE | VV_DELETED | VV_MD | VV_FORCEINSMQ); 2871 if (flags != 0) { 2872 snprintf(buf2, sizeof(buf2), "|VV(0x%lx)", flags); 2873 strlcat(buf, buf2, sizeof(buf)); 2874 } 2875 if (vp->v_iflag & VI_MOUNT) 2876 strlcat(buf, "|VI_MOUNT", sizeof(buf)); 2877 if (vp->v_iflag & VI_AGE) 2878 strlcat(buf, "|VI_AGE", sizeof(buf)); 2879 if (vp->v_iflag & VI_DOOMED) 2880 strlcat(buf, "|VI_DOOMED", sizeof(buf)); 2881 if (vp->v_iflag & VI_FREE) 2882 strlcat(buf, "|VI_FREE", sizeof(buf)); 2883 if (vp->v_iflag & VI_ACTIVE) 2884 strlcat(buf, "|VI_ACTIVE", sizeof(buf)); 2885 if (vp->v_iflag & VI_DOINGINACT) 2886 strlcat(buf, "|VI_DOINGINACT", sizeof(buf)); 2887 if (vp->v_iflag & VI_OWEINACT) 2888 strlcat(buf, "|VI_OWEINACT", sizeof(buf)); 2889 flags = vp->v_iflag & ~(VI_MOUNT | VI_AGE | VI_DOOMED | VI_FREE | 2890 VI_ACTIVE | VI_DOINGINACT | VI_OWEINACT); 2891 if (flags != 0) { 2892 snprintf(buf2, sizeof(buf2), "|VI(0x%lx)", flags); 2893 strlcat(buf, buf2, sizeof(buf)); 2894 } 2895 printf(" flags (%s)\n", buf + 1); 2896 if (mtx_owned(VI_MTX(vp))) 2897 printf(" VI_LOCKed"); 2898 if (vp->v_object != NULL) 2899 printf(" v_object %p ref %d pages %d " 2900 "cleanbuf %d dirtybuf %d\n", 2901 vp->v_object, vp->v_object->ref_count, 2902 vp->v_object->resident_page_count, 2903 vp->v_bufobj.bo_dirty.bv_cnt, 2904 vp->v_bufobj.bo_clean.bv_cnt); 2905 printf(" "); 2906 lockmgr_printinfo(vp->v_vnlock); 2907 if (vp->v_data != NULL) 2908 VOP_PRINT(vp); 2909 } 2910 2911 #ifdef DDB 2912 /* 2913 * List all of the locked vnodes in the system. 2914 * Called when debugging the kernel. 2915 */ 2916 DB_SHOW_COMMAND(lockedvnods, lockedvnodes) 2917 { 2918 struct mount *mp; 2919 struct vnode *vp; 2920 2921 /* 2922 * Note: because this is DDB, we can't obey the locking semantics 2923 * for these structures, which means we could catch an inconsistent 2924 * state and dereference a nasty pointer. Not much to be done 2925 * about that. 2926 */ 2927 db_printf("Locked vnodes\n"); 2928 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 2929 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) { 2930 if (vp->v_type != VMARKER && VOP_ISLOCKED(vp)) 2931 vprint("", vp); 2932 } 2933 } 2934 } 2935 2936 /* 2937 * Show details about the given vnode. 2938 */ 2939 DB_SHOW_COMMAND(vnode, db_show_vnode) 2940 { 2941 struct vnode *vp; 2942 2943 if (!have_addr) 2944 return; 2945 vp = (struct vnode *)addr; 2946 vn_printf(vp, "vnode "); 2947 } 2948 2949 /* 2950 * Show details about the given mount point. 2951 */ 2952 DB_SHOW_COMMAND(mount, db_show_mount) 2953 { 2954 struct mount *mp; 2955 struct vfsopt *opt; 2956 struct statfs *sp; 2957 struct vnode *vp; 2958 char buf[512]; 2959 uint64_t mflags; 2960 u_int flags; 2961 2962 if (!have_addr) { 2963 /* No address given, print short info about all mount points. */ 2964 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 2965 db_printf("%p %s on %s (%s)\n", mp, 2966 mp->mnt_stat.f_mntfromname, 2967 mp->mnt_stat.f_mntonname, 2968 mp->mnt_stat.f_fstypename); 2969 if (db_pager_quit) 2970 break; 2971 } 2972 db_printf("\nMore info: show mount <addr>\n"); 2973 return; 2974 } 2975 2976 mp = (struct mount *)addr; 2977 db_printf("%p %s on %s (%s)\n", mp, mp->mnt_stat.f_mntfromname, 2978 mp->mnt_stat.f_mntonname, mp->mnt_stat.f_fstypename); 2979 2980 buf[0] = '\0'; 2981 mflags = mp->mnt_flag; 2982 #define MNT_FLAG(flag) do { \ 2983 if (mflags & (flag)) { \ 2984 if (buf[0] != '\0') \ 2985 strlcat(buf, ", ", sizeof(buf)); \ 2986 strlcat(buf, (#flag) + 4, sizeof(buf)); \ 2987 mflags &= ~(flag); \ 2988 } \ 2989 } while (0) 2990 MNT_FLAG(MNT_RDONLY); 2991 MNT_FLAG(MNT_SYNCHRONOUS); 2992 MNT_FLAG(MNT_NOEXEC); 2993 MNT_FLAG(MNT_NOSUID); 2994 MNT_FLAG(MNT_NFS4ACLS); 2995 MNT_FLAG(MNT_UNION); 2996 MNT_FLAG(MNT_ASYNC); 2997 MNT_FLAG(MNT_SUIDDIR); 2998 MNT_FLAG(MNT_SOFTDEP); 2999 MNT_FLAG(MNT_NOSYMFOLLOW); 3000 MNT_FLAG(MNT_GJOURNAL); 3001 MNT_FLAG(MNT_MULTILABEL); 3002 MNT_FLAG(MNT_ACLS); 3003 MNT_FLAG(MNT_NOATIME); 3004 MNT_FLAG(MNT_NOCLUSTERR); 3005 MNT_FLAG(MNT_NOCLUSTERW); 3006 MNT_FLAG(MNT_SUJ); 3007 MNT_FLAG(MNT_EXRDONLY); 3008 MNT_FLAG(MNT_EXPORTED); 3009 MNT_FLAG(MNT_DEFEXPORTED); 3010 MNT_FLAG(MNT_EXPORTANON); 3011 MNT_FLAG(MNT_EXKERB); 3012 MNT_FLAG(MNT_EXPUBLIC); 3013 MNT_FLAG(MNT_LOCAL); 3014 MNT_FLAG(MNT_QUOTA); 3015 MNT_FLAG(MNT_ROOTFS); 3016 MNT_FLAG(MNT_USER); 3017 MNT_FLAG(MNT_IGNORE); 3018 MNT_FLAG(MNT_UPDATE); 3019 MNT_FLAG(MNT_DELEXPORT); 3020 MNT_FLAG(MNT_RELOAD); 3021 MNT_FLAG(MNT_FORCE); 3022 MNT_FLAG(MNT_SNAPSHOT); 3023 MNT_FLAG(MNT_BYFSID); 3024 #undef MNT_FLAG 3025 if (mflags != 0) { 3026 if (buf[0] != '\0') 3027 strlcat(buf, ", ", sizeof(buf)); 3028 snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf), 3029 "0x%016jx", mflags); 3030 } 3031 db_printf(" mnt_flag = %s\n", buf); 3032 3033 buf[0] = '\0'; 3034 flags = mp->mnt_kern_flag; 3035 #define MNT_KERN_FLAG(flag) do { \ 3036 if (flags & (flag)) { \ 3037 if (buf[0] != '\0') \ 3038 strlcat(buf, ", ", sizeof(buf)); \ 3039 strlcat(buf, (#flag) + 5, sizeof(buf)); \ 3040 flags &= ~(flag); \ 3041 } \ 3042 } while (0) 3043 MNT_KERN_FLAG(MNTK_UNMOUNTF); 3044 MNT_KERN_FLAG(MNTK_ASYNC); 3045 MNT_KERN_FLAG(MNTK_SOFTDEP); 3046 MNT_KERN_FLAG(MNTK_NOINSMNTQ); 3047 MNT_KERN_FLAG(MNTK_DRAINING); 3048 MNT_KERN_FLAG(MNTK_REFEXPIRE); 3049 MNT_KERN_FLAG(MNTK_EXTENDED_SHARED); 3050 MNT_KERN_FLAG(MNTK_SHARED_WRITES); 3051 MNT_KERN_FLAG(MNTK_NO_IOPF); 3052 MNT_KERN_FLAG(MNTK_VGONE_UPPER); 3053 MNT_KERN_FLAG(MNTK_VGONE_WAITER); 3054 MNT_KERN_FLAG(MNTK_LOOKUP_EXCL_DOTDOT); 3055 MNT_KERN_FLAG(MNTK_MARKER); 3056 MNT_KERN_FLAG(MNTK_NOASYNC); 3057 MNT_KERN_FLAG(MNTK_UNMOUNT); 3058 MNT_KERN_FLAG(MNTK_MWAIT); 3059 MNT_KERN_FLAG(MNTK_SUSPEND); 3060 MNT_KERN_FLAG(MNTK_SUSPEND2); 3061 MNT_KERN_FLAG(MNTK_SUSPENDED); 3062 MNT_KERN_FLAG(MNTK_LOOKUP_SHARED); 3063 MNT_KERN_FLAG(MNTK_NOKNOTE); 3064 #undef MNT_KERN_FLAG 3065 if (flags != 0) { 3066 if (buf[0] != '\0') 3067 strlcat(buf, ", ", sizeof(buf)); 3068 snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf), 3069 "0x%08x", flags); 3070 } 3071 db_printf(" mnt_kern_flag = %s\n", buf); 3072 3073 db_printf(" mnt_opt = "); 3074 opt = TAILQ_FIRST(mp->mnt_opt); 3075 if (opt != NULL) { 3076 db_printf("%s", opt->name); 3077 opt = TAILQ_NEXT(opt, link); 3078 while (opt != NULL) { 3079 db_printf(", %s", opt->name); 3080 opt = TAILQ_NEXT(opt, link); 3081 } 3082 } 3083 db_printf("\n"); 3084 3085 sp = &mp->mnt_stat; 3086 db_printf(" mnt_stat = { version=%u type=%u flags=0x%016jx " 3087 "bsize=%ju iosize=%ju blocks=%ju bfree=%ju bavail=%jd files=%ju " 3088 "ffree=%jd syncwrites=%ju asyncwrites=%ju syncreads=%ju " 3089 "asyncreads=%ju namemax=%u owner=%u fsid=[%d, %d] }\n", 3090 (u_int)sp->f_version, (u_int)sp->f_type, (uintmax_t)sp->f_flags, 3091 (uintmax_t)sp->f_bsize, (uintmax_t)sp->f_iosize, 3092 (uintmax_t)sp->f_blocks, (uintmax_t)sp->f_bfree, 3093 (intmax_t)sp->f_bavail, (uintmax_t)sp->f_files, 3094 (intmax_t)sp->f_ffree, (uintmax_t)sp->f_syncwrites, 3095 (uintmax_t)sp->f_asyncwrites, (uintmax_t)sp->f_syncreads, 3096 (uintmax_t)sp->f_asyncreads, (u_int)sp->f_namemax, 3097 (u_int)sp->f_owner, (int)sp->f_fsid.val[0], (int)sp->f_fsid.val[1]); 3098 3099 db_printf(" mnt_cred = { uid=%u ruid=%u", 3100 (u_int)mp->mnt_cred->cr_uid, (u_int)mp->mnt_cred->cr_ruid); 3101 if (jailed(mp->mnt_cred)) 3102 db_printf(", jail=%d", mp->mnt_cred->cr_prison->pr_id); 3103 db_printf(" }\n"); 3104 db_printf(" mnt_ref = %d\n", mp->mnt_ref); 3105 db_printf(" mnt_gen = %d\n", mp->mnt_gen); 3106 db_printf(" mnt_nvnodelistsize = %d\n", mp->mnt_nvnodelistsize); 3107 db_printf(" mnt_activevnodelistsize = %d\n", 3108 mp->mnt_activevnodelistsize); 3109 db_printf(" mnt_writeopcount = %d\n", mp->mnt_writeopcount); 3110 db_printf(" mnt_maxsymlinklen = %d\n", mp->mnt_maxsymlinklen); 3111 db_printf(" mnt_iosize_max = %d\n", mp->mnt_iosize_max); 3112 db_printf(" mnt_hashseed = %u\n", mp->mnt_hashseed); 3113 db_printf(" mnt_secondary_writes = %d\n", mp->mnt_secondary_writes); 3114 db_printf(" mnt_secondary_accwrites = %d\n", 3115 mp->mnt_secondary_accwrites); 3116 db_printf(" mnt_gjprovider = %s\n", 3117 mp->mnt_gjprovider != NULL ? mp->mnt_gjprovider : "NULL"); 3118 3119 db_printf("\n\nList of active vnodes\n"); 3120 TAILQ_FOREACH(vp, &mp->mnt_activevnodelist, v_actfreelist) { 3121 if (vp->v_type != VMARKER) { 3122 vn_printf(vp, "vnode "); 3123 if (db_pager_quit) 3124 break; 3125 } 3126 } 3127 db_printf("\n\nList of inactive vnodes\n"); 3128 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) { 3129 if (vp->v_type != VMARKER && (vp->v_iflag & VI_ACTIVE) == 0) { 3130 vn_printf(vp, "vnode "); 3131 if (db_pager_quit) 3132 break; 3133 } 3134 } 3135 } 3136 #endif /* DDB */ 3137 3138 /* 3139 * Fill in a struct xvfsconf based on a struct vfsconf. 3140 */ 3141 static int 3142 vfsconf2x(struct sysctl_req *req, struct vfsconf *vfsp) 3143 { 3144 struct xvfsconf xvfsp; 3145 3146 bzero(&xvfsp, sizeof(xvfsp)); 3147 strcpy(xvfsp.vfc_name, vfsp->vfc_name); 3148 xvfsp.vfc_typenum = vfsp->vfc_typenum; 3149 xvfsp.vfc_refcount = vfsp->vfc_refcount; 3150 xvfsp.vfc_flags = vfsp->vfc_flags; 3151 /* 3152 * These are unused in userland, we keep them 3153 * to not break binary compatibility. 3154 */ 3155 xvfsp.vfc_vfsops = NULL; 3156 xvfsp.vfc_next = NULL; 3157 return (SYSCTL_OUT(req, &xvfsp, sizeof(xvfsp))); 3158 } 3159 3160 #ifdef COMPAT_FREEBSD32 3161 struct xvfsconf32 { 3162 uint32_t vfc_vfsops; 3163 char vfc_name[MFSNAMELEN]; 3164 int32_t vfc_typenum; 3165 int32_t vfc_refcount; 3166 int32_t vfc_flags; 3167 uint32_t vfc_next; 3168 }; 3169 3170 static int 3171 vfsconf2x32(struct sysctl_req *req, struct vfsconf *vfsp) 3172 { 3173 struct xvfsconf32 xvfsp; 3174 3175 strcpy(xvfsp.vfc_name, vfsp->vfc_name); 3176 xvfsp.vfc_typenum = vfsp->vfc_typenum; 3177 xvfsp.vfc_refcount = vfsp->vfc_refcount; 3178 xvfsp.vfc_flags = vfsp->vfc_flags; 3179 xvfsp.vfc_vfsops = 0; 3180 xvfsp.vfc_next = 0; 3181 return (SYSCTL_OUT(req, &xvfsp, sizeof(xvfsp))); 3182 } 3183 #endif 3184 3185 /* 3186 * Top level filesystem related information gathering. 3187 */ 3188 static int 3189 sysctl_vfs_conflist(SYSCTL_HANDLER_ARGS) 3190 { 3191 struct vfsconf *vfsp; 3192 int error; 3193 3194 error = 0; 3195 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) { 3196 #ifdef COMPAT_FREEBSD32 3197 if (req->flags & SCTL_MASK32) 3198 error = vfsconf2x32(req, vfsp); 3199 else 3200 #endif 3201 error = vfsconf2x(req, vfsp); 3202 if (error) 3203 break; 3204 } 3205 return (error); 3206 } 3207 3208 SYSCTL_PROC(_vfs, OID_AUTO, conflist, CTLTYPE_OPAQUE | CTLFLAG_RD, 3209 NULL, 0, sysctl_vfs_conflist, 3210 "S,xvfsconf", "List of all configured filesystems"); 3211 3212 #ifndef BURN_BRIDGES 3213 static int sysctl_ovfs_conf(SYSCTL_HANDLER_ARGS); 3214 3215 static int 3216 vfs_sysctl(SYSCTL_HANDLER_ARGS) 3217 { 3218 int *name = (int *)arg1 - 1; /* XXX */ 3219 u_int namelen = arg2 + 1; /* XXX */ 3220 struct vfsconf *vfsp; 3221 3222 log(LOG_WARNING, "userland calling deprecated sysctl, " 3223 "please rebuild world\n"); 3224 3225 #if 1 || defined(COMPAT_PRELITE2) 3226 /* Resolve ambiguity between VFS_VFSCONF and VFS_GENERIC. */ 3227 if (namelen == 1) 3228 return (sysctl_ovfs_conf(oidp, arg1, arg2, req)); 3229 #endif 3230 3231 switch (name[1]) { 3232 case VFS_MAXTYPENUM: 3233 if (namelen != 2) 3234 return (ENOTDIR); 3235 return (SYSCTL_OUT(req, &maxvfsconf, sizeof(int))); 3236 case VFS_CONF: 3237 if (namelen != 3) 3238 return (ENOTDIR); /* overloaded */ 3239 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) 3240 if (vfsp->vfc_typenum == name[2]) 3241 break; 3242 if (vfsp == NULL) 3243 return (EOPNOTSUPP); 3244 #ifdef COMPAT_FREEBSD32 3245 if (req->flags & SCTL_MASK32) 3246 return (vfsconf2x32(req, vfsp)); 3247 else 3248 #endif 3249 return (vfsconf2x(req, vfsp)); 3250 } 3251 return (EOPNOTSUPP); 3252 } 3253 3254 static SYSCTL_NODE(_vfs, VFS_GENERIC, generic, CTLFLAG_RD | CTLFLAG_SKIP, 3255 vfs_sysctl, "Generic filesystem"); 3256 3257 #if 1 || defined(COMPAT_PRELITE2) 3258 3259 static int 3260 sysctl_ovfs_conf(SYSCTL_HANDLER_ARGS) 3261 { 3262 int error; 3263 struct vfsconf *vfsp; 3264 struct ovfsconf ovfs; 3265 3266 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) { 3267 bzero(&ovfs, sizeof(ovfs)); 3268 ovfs.vfc_vfsops = vfsp->vfc_vfsops; /* XXX used as flag */ 3269 strcpy(ovfs.vfc_name, vfsp->vfc_name); 3270 ovfs.vfc_index = vfsp->vfc_typenum; 3271 ovfs.vfc_refcount = vfsp->vfc_refcount; 3272 ovfs.vfc_flags = vfsp->vfc_flags; 3273 error = SYSCTL_OUT(req, &ovfs, sizeof ovfs); 3274 if (error) 3275 return error; 3276 } 3277 return 0; 3278 } 3279 3280 #endif /* 1 || COMPAT_PRELITE2 */ 3281 #endif /* !BURN_BRIDGES */ 3282 3283 #define KINFO_VNODESLOP 10 3284 #ifdef notyet 3285 /* 3286 * Dump vnode list (via sysctl). 3287 */ 3288 /* ARGSUSED */ 3289 static int 3290 sysctl_vnode(SYSCTL_HANDLER_ARGS) 3291 { 3292 struct xvnode *xvn; 3293 struct mount *mp; 3294 struct vnode *vp; 3295 int error, len, n; 3296 3297 /* 3298 * Stale numvnodes access is not fatal here. 3299 */ 3300 req->lock = 0; 3301 len = (numvnodes + KINFO_VNODESLOP) * sizeof *xvn; 3302 if (!req->oldptr) 3303 /* Make an estimate */ 3304 return (SYSCTL_OUT(req, 0, len)); 3305 3306 error = sysctl_wire_old_buffer(req, 0); 3307 if (error != 0) 3308 return (error); 3309 xvn = malloc(len, M_TEMP, M_ZERO | M_WAITOK); 3310 n = 0; 3311 mtx_lock(&mountlist_mtx); 3312 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 3313 if (vfs_busy(mp, MBF_NOWAIT | MBF_MNTLSTLOCK)) 3314 continue; 3315 MNT_ILOCK(mp); 3316 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) { 3317 if (n == len) 3318 break; 3319 vref(vp); 3320 xvn[n].xv_size = sizeof *xvn; 3321 xvn[n].xv_vnode = vp; 3322 xvn[n].xv_id = 0; /* XXX compat */ 3323 #define XV_COPY(field) xvn[n].xv_##field = vp->v_##field 3324 XV_COPY(usecount); 3325 XV_COPY(writecount); 3326 XV_COPY(holdcnt); 3327 XV_COPY(mount); 3328 XV_COPY(numoutput); 3329 XV_COPY(type); 3330 #undef XV_COPY 3331 xvn[n].xv_flag = vp->v_vflag; 3332 3333 switch (vp->v_type) { 3334 case VREG: 3335 case VDIR: 3336 case VLNK: 3337 break; 3338 case VBLK: 3339 case VCHR: 3340 if (vp->v_rdev == NULL) { 3341 vrele(vp); 3342 continue; 3343 } 3344 xvn[n].xv_dev = dev2udev(vp->v_rdev); 3345 break; 3346 case VSOCK: 3347 xvn[n].xv_socket = vp->v_socket; 3348 break; 3349 case VFIFO: 3350 xvn[n].xv_fifo = vp->v_fifoinfo; 3351 break; 3352 case VNON: 3353 case VBAD: 3354 default: 3355 /* shouldn't happen? */ 3356 vrele(vp); 3357 continue; 3358 } 3359 vrele(vp); 3360 ++n; 3361 } 3362 MNT_IUNLOCK(mp); 3363 mtx_lock(&mountlist_mtx); 3364 vfs_unbusy(mp); 3365 if (n == len) 3366 break; 3367 } 3368 mtx_unlock(&mountlist_mtx); 3369 3370 error = SYSCTL_OUT(req, xvn, n * sizeof *xvn); 3371 free(xvn, M_TEMP); 3372 return (error); 3373 } 3374 3375 SYSCTL_PROC(_kern, KERN_VNODE, vnode, CTLTYPE_OPAQUE|CTLFLAG_RD, 3376 0, 0, sysctl_vnode, "S,xvnode", ""); 3377 #endif 3378 3379 /* 3380 * Unmount all filesystems. The list is traversed in reverse order 3381 * of mounting to avoid dependencies. 3382 */ 3383 void 3384 vfs_unmountall(void) 3385 { 3386 struct mount *mp; 3387 struct thread *td; 3388 int error; 3389 3390 CTR1(KTR_VFS, "%s: unmounting all filesystems", __func__); 3391 td = curthread; 3392 3393 /* 3394 * Since this only runs when rebooting, it is not interlocked. 3395 */ 3396 while(!TAILQ_EMPTY(&mountlist)) { 3397 mp = TAILQ_LAST(&mountlist, mntlist); 3398 error = dounmount(mp, MNT_FORCE, td); 3399 if (error) { 3400 TAILQ_REMOVE(&mountlist, mp, mnt_list); 3401 /* 3402 * XXX: Due to the way in which we mount the root 3403 * file system off of devfs, devfs will generate a 3404 * "busy" warning when we try to unmount it before 3405 * the root. Don't print a warning as a result in 3406 * order to avoid false positive errors that may 3407 * cause needless upset. 3408 */ 3409 if (strcmp(mp->mnt_vfc->vfc_name, "devfs") != 0) { 3410 printf("unmount of %s failed (", 3411 mp->mnt_stat.f_mntonname); 3412 if (error == EBUSY) 3413 printf("BUSY)\n"); 3414 else 3415 printf("%d)\n", error); 3416 } 3417 } else { 3418 /* The unmount has removed mp from the mountlist */ 3419 } 3420 } 3421 } 3422 3423 /* 3424 * perform msync on all vnodes under a mount point 3425 * the mount point must be locked. 3426 */ 3427 void 3428 vfs_msync(struct mount *mp, int flags) 3429 { 3430 struct vnode *vp, *mvp; 3431 struct vm_object *obj; 3432 3433 CTR2(KTR_VFS, "%s: mp %p", __func__, mp); 3434 MNT_VNODE_FOREACH_ACTIVE(vp, mp, mvp) { 3435 obj = vp->v_object; 3436 if (obj != NULL && (obj->flags & OBJ_MIGHTBEDIRTY) != 0 && 3437 (flags == MNT_WAIT || VOP_ISLOCKED(vp) == 0)) { 3438 if (!vget(vp, 3439 LK_EXCLUSIVE | LK_RETRY | LK_INTERLOCK, 3440 curthread)) { 3441 if (vp->v_vflag & VV_NOSYNC) { /* unlinked */ 3442 vput(vp); 3443 continue; 3444 } 3445 3446 obj = vp->v_object; 3447 if (obj != NULL) { 3448 VM_OBJECT_WLOCK(obj); 3449 vm_object_page_clean(obj, 0, 0, 3450 flags == MNT_WAIT ? 3451 OBJPC_SYNC : OBJPC_NOSYNC); 3452 VM_OBJECT_WUNLOCK(obj); 3453 } 3454 vput(vp); 3455 } 3456 } else 3457 VI_UNLOCK(vp); 3458 } 3459 } 3460 3461 static void 3462 destroy_vpollinfo_free(struct vpollinfo *vi) 3463 { 3464 3465 knlist_destroy(&vi->vpi_selinfo.si_note); 3466 mtx_destroy(&vi->vpi_lock); 3467 uma_zfree(vnodepoll_zone, vi); 3468 } 3469 3470 static void 3471 destroy_vpollinfo(struct vpollinfo *vi) 3472 { 3473 3474 knlist_clear(&vi->vpi_selinfo.si_note, 1); 3475 seldrain(&vi->vpi_selinfo); 3476 destroy_vpollinfo_free(vi); 3477 } 3478 3479 /* 3480 * Initalize per-vnode helper structure to hold poll-related state. 3481 */ 3482 void 3483 v_addpollinfo(struct vnode *vp) 3484 { 3485 struct vpollinfo *vi; 3486 3487 if (vp->v_pollinfo != NULL) 3488 return; 3489 vi = uma_zalloc(vnodepoll_zone, M_WAITOK); 3490 mtx_init(&vi->vpi_lock, "vnode pollinfo", NULL, MTX_DEF); 3491 knlist_init(&vi->vpi_selinfo.si_note, vp, vfs_knllock, 3492 vfs_knlunlock, vfs_knl_assert_locked, vfs_knl_assert_unlocked); 3493 VI_LOCK(vp); 3494 if (vp->v_pollinfo != NULL) { 3495 VI_UNLOCK(vp); 3496 destroy_vpollinfo_free(vi); 3497 return; 3498 } 3499 vp->v_pollinfo = vi; 3500 VI_UNLOCK(vp); 3501 } 3502 3503 /* 3504 * Record a process's interest in events which might happen to 3505 * a vnode. Because poll uses the historic select-style interface 3506 * internally, this routine serves as both the ``check for any 3507 * pending events'' and the ``record my interest in future events'' 3508 * functions. (These are done together, while the lock is held, 3509 * to avoid race conditions.) 3510 */ 3511 int 3512 vn_pollrecord(struct vnode *vp, struct thread *td, int events) 3513 { 3514 3515 v_addpollinfo(vp); 3516 mtx_lock(&vp->v_pollinfo->vpi_lock); 3517 if (vp->v_pollinfo->vpi_revents & events) { 3518 /* 3519 * This leaves events we are not interested 3520 * in available for the other process which 3521 * which presumably had requested them 3522 * (otherwise they would never have been 3523 * recorded). 3524 */ 3525 events &= vp->v_pollinfo->vpi_revents; 3526 vp->v_pollinfo->vpi_revents &= ~events; 3527 3528 mtx_unlock(&vp->v_pollinfo->vpi_lock); 3529 return (events); 3530 } 3531 vp->v_pollinfo->vpi_events |= events; 3532 selrecord(td, &vp->v_pollinfo->vpi_selinfo); 3533 mtx_unlock(&vp->v_pollinfo->vpi_lock); 3534 return (0); 3535 } 3536 3537 /* 3538 * Routine to create and manage a filesystem syncer vnode. 3539 */ 3540 #define sync_close ((int (*)(struct vop_close_args *))nullop) 3541 static int sync_fsync(struct vop_fsync_args *); 3542 static int sync_inactive(struct vop_inactive_args *); 3543 static int sync_reclaim(struct vop_reclaim_args *); 3544 3545 static struct vop_vector sync_vnodeops = { 3546 .vop_bypass = VOP_EOPNOTSUPP, 3547 .vop_close = sync_close, /* close */ 3548 .vop_fsync = sync_fsync, /* fsync */ 3549 .vop_inactive = sync_inactive, /* inactive */ 3550 .vop_reclaim = sync_reclaim, /* reclaim */ 3551 .vop_lock1 = vop_stdlock, /* lock */ 3552 .vop_unlock = vop_stdunlock, /* unlock */ 3553 .vop_islocked = vop_stdislocked, /* islocked */ 3554 }; 3555 3556 /* 3557 * Create a new filesystem syncer vnode for the specified mount point. 3558 */ 3559 void 3560 vfs_allocate_syncvnode(struct mount *mp) 3561 { 3562 struct vnode *vp; 3563 struct bufobj *bo; 3564 static long start, incr, next; 3565 int error; 3566 3567 /* Allocate a new vnode */ 3568 error = getnewvnode("syncer", mp, &sync_vnodeops, &vp); 3569 if (error != 0) 3570 panic("vfs_allocate_syncvnode: getnewvnode() failed"); 3571 vp->v_type = VNON; 3572 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 3573 vp->v_vflag |= VV_FORCEINSMQ; 3574 error = insmntque(vp, mp); 3575 if (error != 0) 3576 panic("vfs_allocate_syncvnode: insmntque() failed"); 3577 vp->v_vflag &= ~VV_FORCEINSMQ; 3578 VOP_UNLOCK(vp, 0); 3579 /* 3580 * Place the vnode onto the syncer worklist. We attempt to 3581 * scatter them about on the list so that they will go off 3582 * at evenly distributed times even if all the filesystems 3583 * are mounted at once. 3584 */ 3585 next += incr; 3586 if (next == 0 || next > syncer_maxdelay) { 3587 start /= 2; 3588 incr /= 2; 3589 if (start == 0) { 3590 start = syncer_maxdelay / 2; 3591 incr = syncer_maxdelay; 3592 } 3593 next = start; 3594 } 3595 bo = &vp->v_bufobj; 3596 BO_LOCK(bo); 3597 vn_syncer_add_to_worklist(bo, syncdelay > 0 ? next % syncdelay : 0); 3598 /* XXX - vn_syncer_add_to_worklist() also grabs and drops sync_mtx. */ 3599 mtx_lock(&sync_mtx); 3600 sync_vnode_count++; 3601 if (mp->mnt_syncer == NULL) { 3602 mp->mnt_syncer = vp; 3603 vp = NULL; 3604 } 3605 mtx_unlock(&sync_mtx); 3606 BO_UNLOCK(bo); 3607 if (vp != NULL) { 3608 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 3609 vgone(vp); 3610 vput(vp); 3611 } 3612 } 3613 3614 void 3615 vfs_deallocate_syncvnode(struct mount *mp) 3616 { 3617 struct vnode *vp; 3618 3619 mtx_lock(&sync_mtx); 3620 vp = mp->mnt_syncer; 3621 if (vp != NULL) 3622 mp->mnt_syncer = NULL; 3623 mtx_unlock(&sync_mtx); 3624 if (vp != NULL) 3625 vrele(vp); 3626 } 3627 3628 /* 3629 * Do a lazy sync of the filesystem. 3630 */ 3631 static int 3632 sync_fsync(struct vop_fsync_args *ap) 3633 { 3634 struct vnode *syncvp = ap->a_vp; 3635 struct mount *mp = syncvp->v_mount; 3636 int error, save; 3637 struct bufobj *bo; 3638 3639 /* 3640 * We only need to do something if this is a lazy evaluation. 3641 */ 3642 if (ap->a_waitfor != MNT_LAZY) 3643 return (0); 3644 3645 /* 3646 * Move ourselves to the back of the sync list. 3647 */ 3648 bo = &syncvp->v_bufobj; 3649 BO_LOCK(bo); 3650 vn_syncer_add_to_worklist(bo, syncdelay); 3651 BO_UNLOCK(bo); 3652 3653 /* 3654 * Walk the list of vnodes pushing all that are dirty and 3655 * not already on the sync list. 3656 */ 3657 mtx_lock(&mountlist_mtx); 3658 if (vfs_busy(mp, MBF_NOWAIT | MBF_MNTLSTLOCK) != 0) { 3659 mtx_unlock(&mountlist_mtx); 3660 return (0); 3661 } 3662 if (vn_start_write(NULL, &mp, V_NOWAIT) != 0) { 3663 vfs_unbusy(mp); 3664 return (0); 3665 } 3666 save = curthread_pflags_set(TDP_SYNCIO); 3667 vfs_msync(mp, MNT_NOWAIT); 3668 error = VFS_SYNC(mp, MNT_LAZY); 3669 curthread_pflags_restore(save); 3670 vn_finished_write(mp); 3671 vfs_unbusy(mp); 3672 return (error); 3673 } 3674 3675 /* 3676 * The syncer vnode is no referenced. 3677 */ 3678 static int 3679 sync_inactive(struct vop_inactive_args *ap) 3680 { 3681 3682 vgone(ap->a_vp); 3683 return (0); 3684 } 3685 3686 /* 3687 * The syncer vnode is no longer needed and is being decommissioned. 3688 * 3689 * Modifications to the worklist must be protected by sync_mtx. 3690 */ 3691 static int 3692 sync_reclaim(struct vop_reclaim_args *ap) 3693 { 3694 struct vnode *vp = ap->a_vp; 3695 struct bufobj *bo; 3696 3697 bo = &vp->v_bufobj; 3698 BO_LOCK(bo); 3699 mtx_lock(&sync_mtx); 3700 if (vp->v_mount->mnt_syncer == vp) 3701 vp->v_mount->mnt_syncer = NULL; 3702 if (bo->bo_flag & BO_ONWORKLST) { 3703 LIST_REMOVE(bo, bo_synclist); 3704 syncer_worklist_len--; 3705 sync_vnode_count--; 3706 bo->bo_flag &= ~BO_ONWORKLST; 3707 } 3708 mtx_unlock(&sync_mtx); 3709 BO_UNLOCK(bo); 3710 3711 return (0); 3712 } 3713 3714 /* 3715 * Check if vnode represents a disk device 3716 */ 3717 int 3718 vn_isdisk(struct vnode *vp, int *errp) 3719 { 3720 int error; 3721 3722 error = 0; 3723 dev_lock(); 3724 if (vp->v_type != VCHR) 3725 error = ENOTBLK; 3726 else if (vp->v_rdev == NULL) 3727 error = ENXIO; 3728 else if (vp->v_rdev->si_devsw == NULL) 3729 error = ENXIO; 3730 else if (!(vp->v_rdev->si_devsw->d_flags & D_DISK)) 3731 error = ENOTBLK; 3732 dev_unlock(); 3733 if (errp != NULL) 3734 *errp = error; 3735 return (error == 0); 3736 } 3737 3738 /* 3739 * Common filesystem object access control check routine. Accepts a 3740 * vnode's type, "mode", uid and gid, requested access mode, credentials, 3741 * and optional call-by-reference privused argument allowing vaccess() 3742 * to indicate to the caller whether privilege was used to satisfy the 3743 * request (obsoleted). Returns 0 on success, or an errno on failure. 3744 */ 3745 int 3746 vaccess(enum vtype type, mode_t file_mode, uid_t file_uid, gid_t file_gid, 3747 accmode_t accmode, struct ucred *cred, int *privused) 3748 { 3749 accmode_t dac_granted; 3750 accmode_t priv_granted; 3751 3752 KASSERT((accmode & ~(VEXEC | VWRITE | VREAD | VADMIN | VAPPEND)) == 0, 3753 ("invalid bit in accmode")); 3754 KASSERT((accmode & VAPPEND) == 0 || (accmode & VWRITE), 3755 ("VAPPEND without VWRITE")); 3756 3757 /* 3758 * Look for a normal, non-privileged way to access the file/directory 3759 * as requested. If it exists, go with that. 3760 */ 3761 3762 if (privused != NULL) 3763 *privused = 0; 3764 3765 dac_granted = 0; 3766 3767 /* Check the owner. */ 3768 if (cred->cr_uid == file_uid) { 3769 dac_granted |= VADMIN; 3770 if (file_mode & S_IXUSR) 3771 dac_granted |= VEXEC; 3772 if (file_mode & S_IRUSR) 3773 dac_granted |= VREAD; 3774 if (file_mode & S_IWUSR) 3775 dac_granted |= (VWRITE | VAPPEND); 3776 3777 if ((accmode & dac_granted) == accmode) 3778 return (0); 3779 3780 goto privcheck; 3781 } 3782 3783 /* Otherwise, check the groups (first match) */ 3784 if (groupmember(file_gid, cred)) { 3785 if (file_mode & S_IXGRP) 3786 dac_granted |= VEXEC; 3787 if (file_mode & S_IRGRP) 3788 dac_granted |= VREAD; 3789 if (file_mode & S_IWGRP) 3790 dac_granted |= (VWRITE | VAPPEND); 3791 3792 if ((accmode & dac_granted) == accmode) 3793 return (0); 3794 3795 goto privcheck; 3796 } 3797 3798 /* Otherwise, check everyone else. */ 3799 if (file_mode & S_IXOTH) 3800 dac_granted |= VEXEC; 3801 if (file_mode & S_IROTH) 3802 dac_granted |= VREAD; 3803 if (file_mode & S_IWOTH) 3804 dac_granted |= (VWRITE | VAPPEND); 3805 if ((accmode & dac_granted) == accmode) 3806 return (0); 3807 3808 privcheck: 3809 /* 3810 * Build a privilege mask to determine if the set of privileges 3811 * satisfies the requirements when combined with the granted mask 3812 * from above. For each privilege, if the privilege is required, 3813 * bitwise or the request type onto the priv_granted mask. 3814 */ 3815 priv_granted = 0; 3816 3817 if (type == VDIR) { 3818 /* 3819 * For directories, use PRIV_VFS_LOOKUP to satisfy VEXEC 3820 * requests, instead of PRIV_VFS_EXEC. 3821 */ 3822 if ((accmode & VEXEC) && ((dac_granted & VEXEC) == 0) && 3823 !priv_check_cred(cred, PRIV_VFS_LOOKUP, 0)) 3824 priv_granted |= VEXEC; 3825 } else { 3826 /* 3827 * Ensure that at least one execute bit is on. Otherwise, 3828 * a privileged user will always succeed, and we don't want 3829 * this to happen unless the file really is executable. 3830 */ 3831 if ((accmode & VEXEC) && ((dac_granted & VEXEC) == 0) && 3832 (file_mode & (S_IXUSR | S_IXGRP | S_IXOTH)) != 0 && 3833 !priv_check_cred(cred, PRIV_VFS_EXEC, 0)) 3834 priv_granted |= VEXEC; 3835 } 3836 3837 if ((accmode & VREAD) && ((dac_granted & VREAD) == 0) && 3838 !priv_check_cred(cred, PRIV_VFS_READ, 0)) 3839 priv_granted |= VREAD; 3840 3841 if ((accmode & VWRITE) && ((dac_granted & VWRITE) == 0) && 3842 !priv_check_cred(cred, PRIV_VFS_WRITE, 0)) 3843 priv_granted |= (VWRITE | VAPPEND); 3844 3845 if ((accmode & VADMIN) && ((dac_granted & VADMIN) == 0) && 3846 !priv_check_cred(cred, PRIV_VFS_ADMIN, 0)) 3847 priv_granted |= VADMIN; 3848 3849 if ((accmode & (priv_granted | dac_granted)) == accmode) { 3850 /* XXX audit: privilege used */ 3851 if (privused != NULL) 3852 *privused = 1; 3853 return (0); 3854 } 3855 3856 return ((accmode & VADMIN) ? EPERM : EACCES); 3857 } 3858 3859 /* 3860 * Credential check based on process requesting service, and per-attribute 3861 * permissions. 3862 */ 3863 int 3864 extattr_check_cred(struct vnode *vp, int attrnamespace, struct ucred *cred, 3865 struct thread *td, accmode_t accmode) 3866 { 3867 3868 /* 3869 * Kernel-invoked always succeeds. 3870 */ 3871 if (cred == NOCRED) 3872 return (0); 3873 3874 /* 3875 * Do not allow privileged processes in jail to directly manipulate 3876 * system attributes. 3877 */ 3878 switch (attrnamespace) { 3879 case EXTATTR_NAMESPACE_SYSTEM: 3880 /* Potentially should be: return (EPERM); */ 3881 return (priv_check_cred(cred, PRIV_VFS_EXTATTR_SYSTEM, 0)); 3882 case EXTATTR_NAMESPACE_USER: 3883 return (VOP_ACCESS(vp, accmode, cred, td)); 3884 default: 3885 return (EPERM); 3886 } 3887 } 3888 3889 #ifdef DEBUG_VFS_LOCKS 3890 /* 3891 * This only exists to supress warnings from unlocked specfs accesses. It is 3892 * no longer ok to have an unlocked VFS. 3893 */ 3894 #define IGNORE_LOCK(vp) (panicstr != NULL || (vp) == NULL || \ 3895 (vp)->v_type == VCHR || (vp)->v_type == VBAD) 3896 3897 int vfs_badlock_ddb = 1; /* Drop into debugger on violation. */ 3898 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_ddb, CTLFLAG_RW, &vfs_badlock_ddb, 0, 3899 "Drop into debugger on lock violation"); 3900 3901 int vfs_badlock_mutex = 1; /* Check for interlock across VOPs. */ 3902 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_mutex, CTLFLAG_RW, &vfs_badlock_mutex, 3903 0, "Check for interlock across VOPs"); 3904 3905 int vfs_badlock_print = 1; /* Print lock violations. */ 3906 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_print, CTLFLAG_RW, &vfs_badlock_print, 3907 0, "Print lock violations"); 3908 3909 #ifdef KDB 3910 int vfs_badlock_backtrace = 1; /* Print backtrace at lock violations. */ 3911 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_backtrace, CTLFLAG_RW, 3912 &vfs_badlock_backtrace, 0, "Print backtrace at lock violations"); 3913 #endif 3914 3915 static void 3916 vfs_badlock(const char *msg, const char *str, struct vnode *vp) 3917 { 3918 3919 #ifdef KDB 3920 if (vfs_badlock_backtrace) 3921 kdb_backtrace(); 3922 #endif 3923 if (vfs_badlock_print) 3924 printf("%s: %p %s\n", str, (void *)vp, msg); 3925 if (vfs_badlock_ddb) 3926 kdb_enter(KDB_WHY_VFSLOCK, "lock violation"); 3927 } 3928 3929 void 3930 assert_vi_locked(struct vnode *vp, const char *str) 3931 { 3932 3933 if (vfs_badlock_mutex && !mtx_owned(VI_MTX(vp))) 3934 vfs_badlock("interlock is not locked but should be", str, vp); 3935 } 3936 3937 void 3938 assert_vi_unlocked(struct vnode *vp, const char *str) 3939 { 3940 3941 if (vfs_badlock_mutex && mtx_owned(VI_MTX(vp))) 3942 vfs_badlock("interlock is locked but should not be", str, vp); 3943 } 3944 3945 void 3946 assert_vop_locked(struct vnode *vp, const char *str) 3947 { 3948 int locked; 3949 3950 if (!IGNORE_LOCK(vp)) { 3951 locked = VOP_ISLOCKED(vp); 3952 if (locked == 0 || locked == LK_EXCLOTHER) 3953 vfs_badlock("is not locked but should be", str, vp); 3954 } 3955 } 3956 3957 void 3958 assert_vop_unlocked(struct vnode *vp, const char *str) 3959 { 3960 3961 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) == LK_EXCLUSIVE) 3962 vfs_badlock("is locked but should not be", str, vp); 3963 } 3964 3965 void 3966 assert_vop_elocked(struct vnode *vp, const char *str) 3967 { 3968 3969 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) != LK_EXCLUSIVE) 3970 vfs_badlock("is not exclusive locked but should be", str, vp); 3971 } 3972 3973 #if 0 3974 void 3975 assert_vop_elocked_other(struct vnode *vp, const char *str) 3976 { 3977 3978 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) != LK_EXCLOTHER) 3979 vfs_badlock("is not exclusive locked by another thread", 3980 str, vp); 3981 } 3982 3983 void 3984 assert_vop_slocked(struct vnode *vp, const char *str) 3985 { 3986 3987 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) != LK_SHARED) 3988 vfs_badlock("is not locked shared but should be", str, vp); 3989 } 3990 #endif /* 0 */ 3991 #endif /* DEBUG_VFS_LOCKS */ 3992 3993 void 3994 vop_rename_fail(struct vop_rename_args *ap) 3995 { 3996 3997 if (ap->a_tvp != NULL) 3998 vput(ap->a_tvp); 3999 if (ap->a_tdvp == ap->a_tvp) 4000 vrele(ap->a_tdvp); 4001 else 4002 vput(ap->a_tdvp); 4003 vrele(ap->a_fdvp); 4004 vrele(ap->a_fvp); 4005 } 4006 4007 void 4008 vop_rename_pre(void *ap) 4009 { 4010 struct vop_rename_args *a = ap; 4011 4012 #ifdef DEBUG_VFS_LOCKS 4013 if (a->a_tvp) 4014 ASSERT_VI_UNLOCKED(a->a_tvp, "VOP_RENAME"); 4015 ASSERT_VI_UNLOCKED(a->a_tdvp, "VOP_RENAME"); 4016 ASSERT_VI_UNLOCKED(a->a_fvp, "VOP_RENAME"); 4017 ASSERT_VI_UNLOCKED(a->a_fdvp, "VOP_RENAME"); 4018 4019 /* Check the source (from). */ 4020 if (a->a_tdvp->v_vnlock != a->a_fdvp->v_vnlock && 4021 (a->a_tvp == NULL || a->a_tvp->v_vnlock != a->a_fdvp->v_vnlock)) 4022 ASSERT_VOP_UNLOCKED(a->a_fdvp, "vop_rename: fdvp locked"); 4023 if (a->a_tvp == NULL || a->a_tvp->v_vnlock != a->a_fvp->v_vnlock) 4024 ASSERT_VOP_UNLOCKED(a->a_fvp, "vop_rename: fvp locked"); 4025 4026 /* Check the target. */ 4027 if (a->a_tvp) 4028 ASSERT_VOP_LOCKED(a->a_tvp, "vop_rename: tvp not locked"); 4029 ASSERT_VOP_LOCKED(a->a_tdvp, "vop_rename: tdvp not locked"); 4030 #endif 4031 if (a->a_tdvp != a->a_fdvp) 4032 vhold(a->a_fdvp); 4033 if (a->a_tvp != a->a_fvp) 4034 vhold(a->a_fvp); 4035 vhold(a->a_tdvp); 4036 if (a->a_tvp) 4037 vhold(a->a_tvp); 4038 } 4039 4040 void 4041 vop_strategy_pre(void *ap) 4042 { 4043 #ifdef DEBUG_VFS_LOCKS 4044 struct vop_strategy_args *a; 4045 struct buf *bp; 4046 4047 a = ap; 4048 bp = a->a_bp; 4049 4050 /* 4051 * Cluster ops lock their component buffers but not the IO container. 4052 */ 4053 if ((bp->b_flags & B_CLUSTER) != 0) 4054 return; 4055 4056 if (panicstr == NULL && !BUF_ISLOCKED(bp)) { 4057 if (vfs_badlock_print) 4058 printf( 4059 "VOP_STRATEGY: bp is not locked but should be\n"); 4060 if (vfs_badlock_ddb) 4061 kdb_enter(KDB_WHY_VFSLOCK, "lock violation"); 4062 } 4063 #endif 4064 } 4065 4066 void 4067 vop_lock_pre(void *ap) 4068 { 4069 #ifdef DEBUG_VFS_LOCKS 4070 struct vop_lock1_args *a = ap; 4071 4072 if ((a->a_flags & LK_INTERLOCK) == 0) 4073 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_LOCK"); 4074 else 4075 ASSERT_VI_LOCKED(a->a_vp, "VOP_LOCK"); 4076 #endif 4077 } 4078 4079 void 4080 vop_lock_post(void *ap, int rc) 4081 { 4082 #ifdef DEBUG_VFS_LOCKS 4083 struct vop_lock1_args *a = ap; 4084 4085 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_LOCK"); 4086 if (rc == 0 && (a->a_flags & LK_EXCLOTHER) == 0) 4087 ASSERT_VOP_LOCKED(a->a_vp, "VOP_LOCK"); 4088 #endif 4089 } 4090 4091 void 4092 vop_unlock_pre(void *ap) 4093 { 4094 #ifdef DEBUG_VFS_LOCKS 4095 struct vop_unlock_args *a = ap; 4096 4097 if (a->a_flags & LK_INTERLOCK) 4098 ASSERT_VI_LOCKED(a->a_vp, "VOP_UNLOCK"); 4099 ASSERT_VOP_LOCKED(a->a_vp, "VOP_UNLOCK"); 4100 #endif 4101 } 4102 4103 void 4104 vop_unlock_post(void *ap, int rc) 4105 { 4106 #ifdef DEBUG_VFS_LOCKS 4107 struct vop_unlock_args *a = ap; 4108 4109 if (a->a_flags & LK_INTERLOCK) 4110 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_UNLOCK"); 4111 #endif 4112 } 4113 4114 void 4115 vop_create_post(void *ap, int rc) 4116 { 4117 struct vop_create_args *a = ap; 4118 4119 if (!rc) 4120 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 4121 } 4122 4123 void 4124 vop_deleteextattr_post(void *ap, int rc) 4125 { 4126 struct vop_deleteextattr_args *a = ap; 4127 4128 if (!rc) 4129 VFS_KNOTE_LOCKED(a->a_vp, NOTE_ATTRIB); 4130 } 4131 4132 void 4133 vop_link_post(void *ap, int rc) 4134 { 4135 struct vop_link_args *a = ap; 4136 4137 if (!rc) { 4138 VFS_KNOTE_LOCKED(a->a_vp, NOTE_LINK); 4139 VFS_KNOTE_LOCKED(a->a_tdvp, NOTE_WRITE); 4140 } 4141 } 4142 4143 void 4144 vop_mkdir_post(void *ap, int rc) 4145 { 4146 struct vop_mkdir_args *a = ap; 4147 4148 if (!rc) 4149 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE | NOTE_LINK); 4150 } 4151 4152 void 4153 vop_mknod_post(void *ap, int rc) 4154 { 4155 struct vop_mknod_args *a = ap; 4156 4157 if (!rc) 4158 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 4159 } 4160 4161 void 4162 vop_remove_post(void *ap, int rc) 4163 { 4164 struct vop_remove_args *a = ap; 4165 4166 if (!rc) { 4167 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 4168 VFS_KNOTE_LOCKED(a->a_vp, NOTE_DELETE); 4169 } 4170 } 4171 4172 void 4173 vop_rename_post(void *ap, int rc) 4174 { 4175 struct vop_rename_args *a = ap; 4176 4177 if (!rc) { 4178 VFS_KNOTE_UNLOCKED(a->a_fdvp, NOTE_WRITE); 4179 VFS_KNOTE_UNLOCKED(a->a_tdvp, NOTE_WRITE); 4180 VFS_KNOTE_UNLOCKED(a->a_fvp, NOTE_RENAME); 4181 if (a->a_tvp) 4182 VFS_KNOTE_UNLOCKED(a->a_tvp, NOTE_DELETE); 4183 } 4184 if (a->a_tdvp != a->a_fdvp) 4185 vdrop(a->a_fdvp); 4186 if (a->a_tvp != a->a_fvp) 4187 vdrop(a->a_fvp); 4188 vdrop(a->a_tdvp); 4189 if (a->a_tvp) 4190 vdrop(a->a_tvp); 4191 } 4192 4193 void 4194 vop_rmdir_post(void *ap, int rc) 4195 { 4196 struct vop_rmdir_args *a = ap; 4197 4198 if (!rc) { 4199 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE | NOTE_LINK); 4200 VFS_KNOTE_LOCKED(a->a_vp, NOTE_DELETE); 4201 } 4202 } 4203 4204 void 4205 vop_setattr_post(void *ap, int rc) 4206 { 4207 struct vop_setattr_args *a = ap; 4208 4209 if (!rc) 4210 VFS_KNOTE_LOCKED(a->a_vp, NOTE_ATTRIB); 4211 } 4212 4213 void 4214 vop_setextattr_post(void *ap, int rc) 4215 { 4216 struct vop_setextattr_args *a = ap; 4217 4218 if (!rc) 4219 VFS_KNOTE_LOCKED(a->a_vp, NOTE_ATTRIB); 4220 } 4221 4222 void 4223 vop_symlink_post(void *ap, int rc) 4224 { 4225 struct vop_symlink_args *a = ap; 4226 4227 if (!rc) 4228 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 4229 } 4230 4231 static struct knlist fs_knlist; 4232 4233 static void 4234 vfs_event_init(void *arg) 4235 { 4236 knlist_init_mtx(&fs_knlist, NULL); 4237 } 4238 /* XXX - correct order? */ 4239 SYSINIT(vfs_knlist, SI_SUB_VFS, SI_ORDER_ANY, vfs_event_init, NULL); 4240 4241 void 4242 vfs_event_signal(fsid_t *fsid, uint32_t event, intptr_t data __unused) 4243 { 4244 4245 KNOTE_UNLOCKED(&fs_knlist, event); 4246 } 4247 4248 static int filt_fsattach(struct knote *kn); 4249 static void filt_fsdetach(struct knote *kn); 4250 static int filt_fsevent(struct knote *kn, long hint); 4251 4252 struct filterops fs_filtops = { 4253 .f_isfd = 0, 4254 .f_attach = filt_fsattach, 4255 .f_detach = filt_fsdetach, 4256 .f_event = filt_fsevent 4257 }; 4258 4259 static int 4260 filt_fsattach(struct knote *kn) 4261 { 4262 4263 kn->kn_flags |= EV_CLEAR; 4264 knlist_add(&fs_knlist, kn, 0); 4265 return (0); 4266 } 4267 4268 static void 4269 filt_fsdetach(struct knote *kn) 4270 { 4271 4272 knlist_remove(&fs_knlist, kn, 0); 4273 } 4274 4275 static int 4276 filt_fsevent(struct knote *kn, long hint) 4277 { 4278 4279 kn->kn_fflags |= hint; 4280 return (kn->kn_fflags != 0); 4281 } 4282 4283 static int 4284 sysctl_vfs_ctl(SYSCTL_HANDLER_ARGS) 4285 { 4286 struct vfsidctl vc; 4287 int error; 4288 struct mount *mp; 4289 4290 error = SYSCTL_IN(req, &vc, sizeof(vc)); 4291 if (error) 4292 return (error); 4293 if (vc.vc_vers != VFS_CTL_VERS1) 4294 return (EINVAL); 4295 mp = vfs_getvfs(&vc.vc_fsid); 4296 if (mp == NULL) 4297 return (ENOENT); 4298 /* ensure that a specific sysctl goes to the right filesystem. */ 4299 if (strcmp(vc.vc_fstypename, "*") != 0 && 4300 strcmp(vc.vc_fstypename, mp->mnt_vfc->vfc_name) != 0) { 4301 vfs_rel(mp); 4302 return (EINVAL); 4303 } 4304 VCTLTOREQ(&vc, req); 4305 error = VFS_SYSCTL(mp, vc.vc_op, req); 4306 vfs_rel(mp); 4307 return (error); 4308 } 4309 4310 SYSCTL_PROC(_vfs, OID_AUTO, ctl, CTLTYPE_OPAQUE | CTLFLAG_WR, 4311 NULL, 0, sysctl_vfs_ctl, "", 4312 "Sysctl by fsid"); 4313 4314 /* 4315 * Function to initialize a va_filerev field sensibly. 4316 * XXX: Wouldn't a random number make a lot more sense ?? 4317 */ 4318 u_quad_t 4319 init_va_filerev(void) 4320 { 4321 struct bintime bt; 4322 4323 getbinuptime(&bt); 4324 return (((u_quad_t)bt.sec << 32LL) | (bt.frac >> 32LL)); 4325 } 4326 4327 static int filt_vfsread(struct knote *kn, long hint); 4328 static int filt_vfswrite(struct knote *kn, long hint); 4329 static int filt_vfsvnode(struct knote *kn, long hint); 4330 static void filt_vfsdetach(struct knote *kn); 4331 static struct filterops vfsread_filtops = { 4332 .f_isfd = 1, 4333 .f_detach = filt_vfsdetach, 4334 .f_event = filt_vfsread 4335 }; 4336 static struct filterops vfswrite_filtops = { 4337 .f_isfd = 1, 4338 .f_detach = filt_vfsdetach, 4339 .f_event = filt_vfswrite 4340 }; 4341 static struct filterops vfsvnode_filtops = { 4342 .f_isfd = 1, 4343 .f_detach = filt_vfsdetach, 4344 .f_event = filt_vfsvnode 4345 }; 4346 4347 static void 4348 vfs_knllock(void *arg) 4349 { 4350 struct vnode *vp = arg; 4351 4352 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 4353 } 4354 4355 static void 4356 vfs_knlunlock(void *arg) 4357 { 4358 struct vnode *vp = arg; 4359 4360 VOP_UNLOCK(vp, 0); 4361 } 4362 4363 static void 4364 vfs_knl_assert_locked(void *arg) 4365 { 4366 #ifdef DEBUG_VFS_LOCKS 4367 struct vnode *vp = arg; 4368 4369 ASSERT_VOP_LOCKED(vp, "vfs_knl_assert_locked"); 4370 #endif 4371 } 4372 4373 static void 4374 vfs_knl_assert_unlocked(void *arg) 4375 { 4376 #ifdef DEBUG_VFS_LOCKS 4377 struct vnode *vp = arg; 4378 4379 ASSERT_VOP_UNLOCKED(vp, "vfs_knl_assert_unlocked"); 4380 #endif 4381 } 4382 4383 int 4384 vfs_kqfilter(struct vop_kqfilter_args *ap) 4385 { 4386 struct vnode *vp = ap->a_vp; 4387 struct knote *kn = ap->a_kn; 4388 struct knlist *knl; 4389 4390 switch (kn->kn_filter) { 4391 case EVFILT_READ: 4392 kn->kn_fop = &vfsread_filtops; 4393 break; 4394 case EVFILT_WRITE: 4395 kn->kn_fop = &vfswrite_filtops; 4396 break; 4397 case EVFILT_VNODE: 4398 kn->kn_fop = &vfsvnode_filtops; 4399 break; 4400 default: 4401 return (EINVAL); 4402 } 4403 4404 kn->kn_hook = (caddr_t)vp; 4405 4406 v_addpollinfo(vp); 4407 if (vp->v_pollinfo == NULL) 4408 return (ENOMEM); 4409 knl = &vp->v_pollinfo->vpi_selinfo.si_note; 4410 vhold(vp); 4411 knlist_add(knl, kn, 0); 4412 4413 return (0); 4414 } 4415 4416 /* 4417 * Detach knote from vnode 4418 */ 4419 static void 4420 filt_vfsdetach(struct knote *kn) 4421 { 4422 struct vnode *vp = (struct vnode *)kn->kn_hook; 4423 4424 KASSERT(vp->v_pollinfo != NULL, ("Missing v_pollinfo")); 4425 knlist_remove(&vp->v_pollinfo->vpi_selinfo.si_note, kn, 0); 4426 vdrop(vp); 4427 } 4428 4429 /*ARGSUSED*/ 4430 static int 4431 filt_vfsread(struct knote *kn, long hint) 4432 { 4433 struct vnode *vp = (struct vnode *)kn->kn_hook; 4434 struct vattr va; 4435 int res; 4436 4437 /* 4438 * filesystem is gone, so set the EOF flag and schedule 4439 * the knote for deletion. 4440 */ 4441 if (hint == NOTE_REVOKE) { 4442 VI_LOCK(vp); 4443 kn->kn_flags |= (EV_EOF | EV_ONESHOT); 4444 VI_UNLOCK(vp); 4445 return (1); 4446 } 4447 4448 if (VOP_GETATTR(vp, &va, curthread->td_ucred)) 4449 return (0); 4450 4451 VI_LOCK(vp); 4452 kn->kn_data = va.va_size - kn->kn_fp->f_offset; 4453 res = (kn->kn_data != 0); 4454 VI_UNLOCK(vp); 4455 return (res); 4456 } 4457 4458 /*ARGSUSED*/ 4459 static int 4460 filt_vfswrite(struct knote *kn, long hint) 4461 { 4462 struct vnode *vp = (struct vnode *)kn->kn_hook; 4463 4464 VI_LOCK(vp); 4465 4466 /* 4467 * filesystem is gone, so set the EOF flag and schedule 4468 * the knote for deletion. 4469 */ 4470 if (hint == NOTE_REVOKE) 4471 kn->kn_flags |= (EV_EOF | EV_ONESHOT); 4472 4473 kn->kn_data = 0; 4474 VI_UNLOCK(vp); 4475 return (1); 4476 } 4477 4478 static int 4479 filt_vfsvnode(struct knote *kn, long hint) 4480 { 4481 struct vnode *vp = (struct vnode *)kn->kn_hook; 4482 int res; 4483 4484 VI_LOCK(vp); 4485 if (kn->kn_sfflags & hint) 4486 kn->kn_fflags |= hint; 4487 if (hint == NOTE_REVOKE) { 4488 kn->kn_flags |= EV_EOF; 4489 VI_UNLOCK(vp); 4490 return (1); 4491 } 4492 res = (kn->kn_fflags != 0); 4493 VI_UNLOCK(vp); 4494 return (res); 4495 } 4496 4497 int 4498 vfs_read_dirent(struct vop_readdir_args *ap, struct dirent *dp, off_t off) 4499 { 4500 int error; 4501 4502 if (dp->d_reclen > ap->a_uio->uio_resid) 4503 return (ENAMETOOLONG); 4504 error = uiomove(dp, dp->d_reclen, ap->a_uio); 4505 if (error) { 4506 if (ap->a_ncookies != NULL) { 4507 if (ap->a_cookies != NULL) 4508 free(ap->a_cookies, M_TEMP); 4509 ap->a_cookies = NULL; 4510 *ap->a_ncookies = 0; 4511 } 4512 return (error); 4513 } 4514 if (ap->a_ncookies == NULL) 4515 return (0); 4516 4517 KASSERT(ap->a_cookies, 4518 ("NULL ap->a_cookies value with non-NULL ap->a_ncookies!")); 4519 4520 *ap->a_cookies = realloc(*ap->a_cookies, 4521 (*ap->a_ncookies + 1) * sizeof(u_long), M_TEMP, M_WAITOK | M_ZERO); 4522 (*ap->a_cookies)[*ap->a_ncookies] = off; 4523 return (0); 4524 } 4525 4526 /* 4527 * Mark for update the access time of the file if the filesystem 4528 * supports VOP_MARKATIME. This functionality is used by execve and 4529 * mmap, so we want to avoid the I/O implied by directly setting 4530 * va_atime for the sake of efficiency. 4531 */ 4532 void 4533 vfs_mark_atime(struct vnode *vp, struct ucred *cred) 4534 { 4535 struct mount *mp; 4536 4537 mp = vp->v_mount; 4538 ASSERT_VOP_LOCKED(vp, "vfs_mark_atime"); 4539 if (mp != NULL && (mp->mnt_flag & (MNT_NOATIME | MNT_RDONLY)) == 0) 4540 (void)VOP_MARKATIME(vp); 4541 } 4542 4543 /* 4544 * The purpose of this routine is to remove granularity from accmode_t, 4545 * reducing it into standard unix access bits - VEXEC, VREAD, VWRITE, 4546 * VADMIN and VAPPEND. 4547 * 4548 * If it returns 0, the caller is supposed to continue with the usual 4549 * access checks using 'accmode' as modified by this routine. If it 4550 * returns nonzero value, the caller is supposed to return that value 4551 * as errno. 4552 * 4553 * Note that after this routine runs, accmode may be zero. 4554 */ 4555 int 4556 vfs_unixify_accmode(accmode_t *accmode) 4557 { 4558 /* 4559 * There is no way to specify explicit "deny" rule using 4560 * file mode or POSIX.1e ACLs. 4561 */ 4562 if (*accmode & VEXPLICIT_DENY) { 4563 *accmode = 0; 4564 return (0); 4565 } 4566 4567 /* 4568 * None of these can be translated into usual access bits. 4569 * Also, the common case for NFSv4 ACLs is to not contain 4570 * either of these bits. Caller should check for VWRITE 4571 * on the containing directory instead. 4572 */ 4573 if (*accmode & (VDELETE_CHILD | VDELETE)) 4574 return (EPERM); 4575 4576 if (*accmode & VADMIN_PERMS) { 4577 *accmode &= ~VADMIN_PERMS; 4578 *accmode |= VADMIN; 4579 } 4580 4581 /* 4582 * There is no way to deny VREAD_ATTRIBUTES, VREAD_ACL 4583 * or VSYNCHRONIZE using file mode or POSIX.1e ACL. 4584 */ 4585 *accmode &= ~(VSTAT_PERMS | VSYNCHRONIZE); 4586 4587 return (0); 4588 } 4589 4590 /* 4591 * These are helper functions for filesystems to traverse all 4592 * their vnodes. See MNT_VNODE_FOREACH_ALL() in sys/mount.h. 4593 * 4594 * This interface replaces MNT_VNODE_FOREACH. 4595 */ 4596 4597 MALLOC_DEFINE(M_VNODE_MARKER, "vnodemarker", "vnode marker"); 4598 4599 struct vnode * 4600 __mnt_vnode_next_all(struct vnode **mvp, struct mount *mp) 4601 { 4602 struct vnode *vp; 4603 4604 if (should_yield()) 4605 kern_yield(PRI_USER); 4606 MNT_ILOCK(mp); 4607 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch")); 4608 vp = TAILQ_NEXT(*mvp, v_nmntvnodes); 4609 while (vp != NULL && (vp->v_type == VMARKER || 4610 (vp->v_iflag & VI_DOOMED) != 0)) 4611 vp = TAILQ_NEXT(vp, v_nmntvnodes); 4612 4613 /* Check if we are done */ 4614 if (vp == NULL) { 4615 __mnt_vnode_markerfree_all(mvp, mp); 4616 /* MNT_IUNLOCK(mp); -- done in above function */ 4617 mtx_assert(MNT_MTX(mp), MA_NOTOWNED); 4618 return (NULL); 4619 } 4620 TAILQ_REMOVE(&mp->mnt_nvnodelist, *mvp, v_nmntvnodes); 4621 TAILQ_INSERT_AFTER(&mp->mnt_nvnodelist, vp, *mvp, v_nmntvnodes); 4622 VI_LOCK(vp); 4623 MNT_IUNLOCK(mp); 4624 return (vp); 4625 } 4626 4627 struct vnode * 4628 __mnt_vnode_first_all(struct vnode **mvp, struct mount *mp) 4629 { 4630 struct vnode *vp; 4631 4632 *mvp = malloc(sizeof(struct vnode), M_VNODE_MARKER, M_WAITOK | M_ZERO); 4633 MNT_ILOCK(mp); 4634 MNT_REF(mp); 4635 (*mvp)->v_type = VMARKER; 4636 4637 vp = TAILQ_FIRST(&mp->mnt_nvnodelist); 4638 while (vp != NULL && (vp->v_type == VMARKER || 4639 (vp->v_iflag & VI_DOOMED) != 0)) 4640 vp = TAILQ_NEXT(vp, v_nmntvnodes); 4641 4642 /* Check if we are done */ 4643 if (vp == NULL) { 4644 MNT_REL(mp); 4645 MNT_IUNLOCK(mp); 4646 free(*mvp, M_VNODE_MARKER); 4647 *mvp = NULL; 4648 return (NULL); 4649 } 4650 (*mvp)->v_mount = mp; 4651 TAILQ_INSERT_AFTER(&mp->mnt_nvnodelist, vp, *mvp, v_nmntvnodes); 4652 VI_LOCK(vp); 4653 MNT_IUNLOCK(mp); 4654 return (vp); 4655 } 4656 4657 4658 void 4659 __mnt_vnode_markerfree_all(struct vnode **mvp, struct mount *mp) 4660 { 4661 4662 if (*mvp == NULL) { 4663 MNT_IUNLOCK(mp); 4664 return; 4665 } 4666 4667 mtx_assert(MNT_MTX(mp), MA_OWNED); 4668 4669 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch")); 4670 TAILQ_REMOVE(&mp->mnt_nvnodelist, *mvp, v_nmntvnodes); 4671 MNT_REL(mp); 4672 MNT_IUNLOCK(mp); 4673 free(*mvp, M_VNODE_MARKER); 4674 *mvp = NULL; 4675 } 4676 4677 /* 4678 * These are helper functions for filesystems to traverse their 4679 * active vnodes. See MNT_VNODE_FOREACH_ACTIVE() in sys/mount.h 4680 */ 4681 static void 4682 mnt_vnode_markerfree_active(struct vnode **mvp, struct mount *mp) 4683 { 4684 4685 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch")); 4686 4687 MNT_ILOCK(mp); 4688 MNT_REL(mp); 4689 MNT_IUNLOCK(mp); 4690 free(*mvp, M_VNODE_MARKER); 4691 *mvp = NULL; 4692 } 4693 4694 static struct vnode * 4695 mnt_vnode_next_active(struct vnode **mvp, struct mount *mp) 4696 { 4697 struct vnode *vp, *nvp; 4698 4699 mtx_assert(&vnode_free_list_mtx, MA_OWNED); 4700 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch")); 4701 restart: 4702 vp = TAILQ_NEXT(*mvp, v_actfreelist); 4703 TAILQ_REMOVE(&mp->mnt_activevnodelist, *mvp, v_actfreelist); 4704 while (vp != NULL) { 4705 if (vp->v_type == VMARKER) { 4706 vp = TAILQ_NEXT(vp, v_actfreelist); 4707 continue; 4708 } 4709 if (!VI_TRYLOCK(vp)) { 4710 if (mp_ncpus == 1 || should_yield()) { 4711 TAILQ_INSERT_BEFORE(vp, *mvp, v_actfreelist); 4712 mtx_unlock(&vnode_free_list_mtx); 4713 pause("vnacti", 1); 4714 mtx_lock(&vnode_free_list_mtx); 4715 goto restart; 4716 } 4717 continue; 4718 } 4719 KASSERT(vp->v_type != VMARKER, ("locked marker %p", vp)); 4720 KASSERT(vp->v_mount == mp || vp->v_mount == NULL, 4721 ("alien vnode on the active list %p %p", vp, mp)); 4722 if (vp->v_mount == mp && (vp->v_iflag & VI_DOOMED) == 0) 4723 break; 4724 nvp = TAILQ_NEXT(vp, v_actfreelist); 4725 VI_UNLOCK(vp); 4726 vp = nvp; 4727 } 4728 4729 /* Check if we are done */ 4730 if (vp == NULL) { 4731 mtx_unlock(&vnode_free_list_mtx); 4732 mnt_vnode_markerfree_active(mvp, mp); 4733 return (NULL); 4734 } 4735 TAILQ_INSERT_AFTER(&mp->mnt_activevnodelist, vp, *mvp, v_actfreelist); 4736 mtx_unlock(&vnode_free_list_mtx); 4737 ASSERT_VI_LOCKED(vp, "active iter"); 4738 KASSERT((vp->v_iflag & VI_ACTIVE) != 0, ("Non-active vp %p", vp)); 4739 return (vp); 4740 } 4741 4742 struct vnode * 4743 __mnt_vnode_next_active(struct vnode **mvp, struct mount *mp) 4744 { 4745 4746 if (should_yield()) 4747 kern_yield(PRI_USER); 4748 mtx_lock(&vnode_free_list_mtx); 4749 return (mnt_vnode_next_active(mvp, mp)); 4750 } 4751 4752 struct vnode * 4753 __mnt_vnode_first_active(struct vnode **mvp, struct mount *mp) 4754 { 4755 struct vnode *vp; 4756 4757 *mvp = malloc(sizeof(struct vnode), M_VNODE_MARKER, M_WAITOK | M_ZERO); 4758 MNT_ILOCK(mp); 4759 MNT_REF(mp); 4760 MNT_IUNLOCK(mp); 4761 (*mvp)->v_type = VMARKER; 4762 (*mvp)->v_mount = mp; 4763 4764 mtx_lock(&vnode_free_list_mtx); 4765 vp = TAILQ_FIRST(&mp->mnt_activevnodelist); 4766 if (vp == NULL) { 4767 mtx_unlock(&vnode_free_list_mtx); 4768 mnt_vnode_markerfree_active(mvp, mp); 4769 return (NULL); 4770 } 4771 TAILQ_INSERT_BEFORE(vp, *mvp, v_actfreelist); 4772 return (mnt_vnode_next_active(mvp, mp)); 4773 } 4774 4775 void 4776 __mnt_vnode_markerfree_active(struct vnode **mvp, struct mount *mp) 4777 { 4778 4779 if (*mvp == NULL) 4780 return; 4781 4782 mtx_lock(&vnode_free_list_mtx); 4783 TAILQ_REMOVE(&mp->mnt_activevnodelist, *mvp, v_actfreelist); 4784 mtx_unlock(&vnode_free_list_mtx); 4785 mnt_vnode_markerfree_active(mvp, mp); 4786 } 4787