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 if (vp->v_holdcnt > 0) { 2347 VI_UNLOCK(vp); 2348 return; 2349 } 2350 if ((vp->v_iflag & VI_DOOMED) == 0) { 2351 /* 2352 * Mark a vnode as free: remove it from its active list 2353 * and put it up for recycling on the freelist. 2354 */ 2355 VNASSERT(vp->v_op != NULL, vp, 2356 ("vdropl: vnode already reclaimed.")); 2357 VNASSERT((vp->v_iflag & VI_FREE) == 0, vp, 2358 ("vnode already free")); 2359 VNASSERT(VSHOULDFREE(vp), vp, 2360 ("vdropl: freeing when we shouldn't")); 2361 active = vp->v_iflag & VI_ACTIVE; 2362 vp->v_iflag &= ~VI_ACTIVE; 2363 mp = vp->v_mount; 2364 mtx_lock(&vnode_free_list_mtx); 2365 if (active) { 2366 TAILQ_REMOVE(&mp->mnt_activevnodelist, vp, 2367 v_actfreelist); 2368 mp->mnt_activevnodelistsize--; 2369 } 2370 if (vp->v_iflag & VI_AGE) { 2371 TAILQ_INSERT_HEAD(&vnode_free_list, vp, v_actfreelist); 2372 } else { 2373 TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_actfreelist); 2374 } 2375 freevnodes++; 2376 vp->v_iflag &= ~VI_AGE; 2377 vp->v_iflag |= VI_FREE; 2378 mtx_unlock(&vnode_free_list_mtx); 2379 VI_UNLOCK(vp); 2380 return; 2381 } 2382 /* 2383 * The vnode has been marked for destruction, so free it. 2384 */ 2385 CTR2(KTR_VFS, "%s: destroying the vnode %p", __func__, vp); 2386 mtx_lock(&vnode_free_list_mtx); 2387 numvnodes--; 2388 mtx_unlock(&vnode_free_list_mtx); 2389 bo = &vp->v_bufobj; 2390 VNASSERT((vp->v_iflag & VI_FREE) == 0, vp, 2391 ("cleaned vnode still on the free list.")); 2392 VNASSERT(vp->v_data == NULL, vp, ("cleaned vnode isn't")); 2393 VNASSERT(vp->v_holdcnt == 0, vp, ("Non-zero hold count")); 2394 VNASSERT(vp->v_usecount == 0, vp, ("Non-zero use count")); 2395 VNASSERT(vp->v_writecount == 0, vp, ("Non-zero write count")); 2396 VNASSERT(bo->bo_numoutput == 0, vp, ("Clean vnode has pending I/O's")); 2397 VNASSERT(bo->bo_clean.bv_cnt == 0, vp, ("cleanbufcnt not 0")); 2398 VNASSERT(pctrie_is_empty(&bo->bo_clean.bv_root), vp, 2399 ("clean blk trie not empty")); 2400 VNASSERT(bo->bo_dirty.bv_cnt == 0, vp, ("dirtybufcnt not 0")); 2401 VNASSERT(pctrie_is_empty(&bo->bo_dirty.bv_root), vp, 2402 ("dirty blk trie not empty")); 2403 VNASSERT(TAILQ_EMPTY(&vp->v_cache_dst), vp, ("vp has namecache dst")); 2404 VNASSERT(LIST_EMPTY(&vp->v_cache_src), vp, ("vp has namecache src")); 2405 VNASSERT(vp->v_cache_dd == NULL, vp, ("vp has namecache for ..")); 2406 VI_UNLOCK(vp); 2407 #ifdef MAC 2408 mac_vnode_destroy(vp); 2409 #endif 2410 if (vp->v_pollinfo != NULL) 2411 destroy_vpollinfo(vp->v_pollinfo); 2412 #ifdef INVARIANTS 2413 /* XXX Elsewhere we detect an already freed vnode via NULL v_op. */ 2414 vp->v_op = NULL; 2415 #endif 2416 rangelock_destroy(&vp->v_rl); 2417 lockdestroy(vp->v_vnlock); 2418 mtx_destroy(&vp->v_interlock); 2419 rw_destroy(BO_LOCKPTR(bo)); 2420 uma_zfree(vnode_zone, vp); 2421 } 2422 2423 /* 2424 * Call VOP_INACTIVE on the vnode and manage the DOINGINACT and OWEINACT 2425 * flags. DOINGINACT prevents us from recursing in calls to vinactive. 2426 * OWEINACT tracks whether a vnode missed a call to inactive due to a 2427 * failed lock upgrade. 2428 */ 2429 void 2430 vinactive(struct vnode *vp, struct thread *td) 2431 { 2432 struct vm_object *obj; 2433 2434 ASSERT_VOP_ELOCKED(vp, "vinactive"); 2435 ASSERT_VI_LOCKED(vp, "vinactive"); 2436 VNASSERT((vp->v_iflag & VI_DOINGINACT) == 0, vp, 2437 ("vinactive: recursed on VI_DOINGINACT")); 2438 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2439 vp->v_iflag |= VI_DOINGINACT; 2440 vp->v_iflag &= ~VI_OWEINACT; 2441 VI_UNLOCK(vp); 2442 /* 2443 * Before moving off the active list, we must be sure that any 2444 * modified pages are on the vnode's dirty list since these will 2445 * no longer be checked once the vnode is on the inactive list. 2446 * Because the vnode vm object keeps a hold reference on the vnode 2447 * if there is at least one resident non-cached page, the vnode 2448 * cannot leave the active list without the page cleanup done. 2449 */ 2450 obj = vp->v_object; 2451 if (obj != NULL && (obj->flags & OBJ_MIGHTBEDIRTY) != 0) { 2452 VM_OBJECT_WLOCK(obj); 2453 vm_object_page_clean(obj, 0, 0, OBJPC_NOSYNC); 2454 VM_OBJECT_WUNLOCK(obj); 2455 } 2456 VOP_INACTIVE(vp, td); 2457 VI_LOCK(vp); 2458 VNASSERT(vp->v_iflag & VI_DOINGINACT, vp, 2459 ("vinactive: lost VI_DOINGINACT")); 2460 vp->v_iflag &= ~VI_DOINGINACT; 2461 } 2462 2463 /* 2464 * Remove any vnodes in the vnode table belonging to mount point mp. 2465 * 2466 * If FORCECLOSE is not specified, there should not be any active ones, 2467 * return error if any are found (nb: this is a user error, not a 2468 * system error). If FORCECLOSE is specified, detach any active vnodes 2469 * that are found. 2470 * 2471 * If WRITECLOSE is set, only flush out regular file vnodes open for 2472 * writing. 2473 * 2474 * SKIPSYSTEM causes any vnodes marked VV_SYSTEM to be skipped. 2475 * 2476 * `rootrefs' specifies the base reference count for the root vnode 2477 * of this filesystem. The root vnode is considered busy if its 2478 * v_usecount exceeds this value. On a successful return, vflush(, td) 2479 * will call vrele() on the root vnode exactly rootrefs times. 2480 * If the SKIPSYSTEM or WRITECLOSE flags are specified, rootrefs must 2481 * be zero. 2482 */ 2483 #ifdef DIAGNOSTIC 2484 static int busyprt = 0; /* print out busy vnodes */ 2485 SYSCTL_INT(_debug, OID_AUTO, busyprt, CTLFLAG_RW, &busyprt, 0, "Print out busy vnodes"); 2486 #endif 2487 2488 int 2489 vflush(struct mount *mp, int rootrefs, int flags, struct thread *td) 2490 { 2491 struct vnode *vp, *mvp, *rootvp = NULL; 2492 struct vattr vattr; 2493 int busy = 0, error; 2494 2495 CTR4(KTR_VFS, "%s: mp %p with rootrefs %d and flags %d", __func__, mp, 2496 rootrefs, flags); 2497 if (rootrefs > 0) { 2498 KASSERT((flags & (SKIPSYSTEM | WRITECLOSE)) == 0, 2499 ("vflush: bad args")); 2500 /* 2501 * Get the filesystem root vnode. We can vput() it 2502 * immediately, since with rootrefs > 0, it won't go away. 2503 */ 2504 if ((error = VFS_ROOT(mp, LK_EXCLUSIVE, &rootvp)) != 0) { 2505 CTR2(KTR_VFS, "%s: vfs_root lookup failed with %d", 2506 __func__, error); 2507 return (error); 2508 } 2509 vput(rootvp); 2510 } 2511 loop: 2512 MNT_VNODE_FOREACH_ALL(vp, mp, mvp) { 2513 vholdl(vp); 2514 error = vn_lock(vp, LK_INTERLOCK | LK_EXCLUSIVE); 2515 if (error) { 2516 vdrop(vp); 2517 MNT_VNODE_FOREACH_ALL_ABORT(mp, mvp); 2518 goto loop; 2519 } 2520 /* 2521 * Skip over a vnodes marked VV_SYSTEM. 2522 */ 2523 if ((flags & SKIPSYSTEM) && (vp->v_vflag & VV_SYSTEM)) { 2524 VOP_UNLOCK(vp, 0); 2525 vdrop(vp); 2526 continue; 2527 } 2528 /* 2529 * If WRITECLOSE is set, flush out unlinked but still open 2530 * files (even if open only for reading) and regular file 2531 * vnodes open for writing. 2532 */ 2533 if (flags & WRITECLOSE) { 2534 if (vp->v_object != NULL) { 2535 VM_OBJECT_WLOCK(vp->v_object); 2536 vm_object_page_clean(vp->v_object, 0, 0, 0); 2537 VM_OBJECT_WUNLOCK(vp->v_object); 2538 } 2539 error = VOP_FSYNC(vp, MNT_WAIT, td); 2540 if (error != 0) { 2541 VOP_UNLOCK(vp, 0); 2542 vdrop(vp); 2543 MNT_VNODE_FOREACH_ALL_ABORT(mp, mvp); 2544 return (error); 2545 } 2546 error = VOP_GETATTR(vp, &vattr, td->td_ucred); 2547 VI_LOCK(vp); 2548 2549 if ((vp->v_type == VNON || 2550 (error == 0 && vattr.va_nlink > 0)) && 2551 (vp->v_writecount == 0 || vp->v_type != VREG)) { 2552 VOP_UNLOCK(vp, 0); 2553 vdropl(vp); 2554 continue; 2555 } 2556 } else 2557 VI_LOCK(vp); 2558 /* 2559 * With v_usecount == 0, all we need to do is clear out the 2560 * vnode data structures and we are done. 2561 * 2562 * If FORCECLOSE is set, forcibly close the vnode. 2563 */ 2564 if (vp->v_usecount == 0 || (flags & FORCECLOSE)) { 2565 VNASSERT(vp->v_usecount == 0 || 2566 (vp->v_type != VCHR && vp->v_type != VBLK), vp, 2567 ("device VNODE %p is FORCECLOSED", vp)); 2568 vgonel(vp); 2569 } else { 2570 busy++; 2571 #ifdef DIAGNOSTIC 2572 if (busyprt) 2573 vprint("vflush: busy vnode", vp); 2574 #endif 2575 } 2576 VOP_UNLOCK(vp, 0); 2577 vdropl(vp); 2578 } 2579 if (rootrefs > 0 && (flags & FORCECLOSE) == 0) { 2580 /* 2581 * If just the root vnode is busy, and if its refcount 2582 * is equal to `rootrefs', then go ahead and kill it. 2583 */ 2584 VI_LOCK(rootvp); 2585 KASSERT(busy > 0, ("vflush: not busy")); 2586 VNASSERT(rootvp->v_usecount >= rootrefs, rootvp, 2587 ("vflush: usecount %d < rootrefs %d", 2588 rootvp->v_usecount, rootrefs)); 2589 if (busy == 1 && rootvp->v_usecount == rootrefs) { 2590 VOP_LOCK(rootvp, LK_EXCLUSIVE|LK_INTERLOCK); 2591 vgone(rootvp); 2592 VOP_UNLOCK(rootvp, 0); 2593 busy = 0; 2594 } else 2595 VI_UNLOCK(rootvp); 2596 } 2597 if (busy) { 2598 CTR2(KTR_VFS, "%s: failing as %d vnodes are busy", __func__, 2599 busy); 2600 return (EBUSY); 2601 } 2602 for (; rootrefs > 0; rootrefs--) 2603 vrele(rootvp); 2604 return (0); 2605 } 2606 2607 /* 2608 * Recycle an unused vnode to the front of the free list. 2609 */ 2610 int 2611 vrecycle(struct vnode *vp) 2612 { 2613 int recycled; 2614 2615 ASSERT_VOP_ELOCKED(vp, "vrecycle"); 2616 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2617 recycled = 0; 2618 VI_LOCK(vp); 2619 if (vp->v_usecount == 0) { 2620 recycled = 1; 2621 vgonel(vp); 2622 } 2623 VI_UNLOCK(vp); 2624 return (recycled); 2625 } 2626 2627 /* 2628 * Eliminate all activity associated with a vnode 2629 * in preparation for reuse. 2630 */ 2631 void 2632 vgone(struct vnode *vp) 2633 { 2634 VI_LOCK(vp); 2635 vgonel(vp); 2636 VI_UNLOCK(vp); 2637 } 2638 2639 static void 2640 notify_lowervp_vfs_dummy(struct mount *mp __unused, 2641 struct vnode *lowervp __unused) 2642 { 2643 } 2644 2645 /* 2646 * Notify upper mounts about reclaimed or unlinked vnode. 2647 */ 2648 void 2649 vfs_notify_upper(struct vnode *vp, int event) 2650 { 2651 static struct vfsops vgonel_vfsops = { 2652 .vfs_reclaim_lowervp = notify_lowervp_vfs_dummy, 2653 .vfs_unlink_lowervp = notify_lowervp_vfs_dummy, 2654 }; 2655 struct mount *mp, *ump, *mmp; 2656 2657 mp = vp->v_mount; 2658 if (mp == NULL) 2659 return; 2660 2661 MNT_ILOCK(mp); 2662 if (TAILQ_EMPTY(&mp->mnt_uppers)) 2663 goto unlock; 2664 MNT_IUNLOCK(mp); 2665 mmp = malloc(sizeof(struct mount), M_TEMP, M_WAITOK | M_ZERO); 2666 mmp->mnt_op = &vgonel_vfsops; 2667 mmp->mnt_kern_flag |= MNTK_MARKER; 2668 MNT_ILOCK(mp); 2669 mp->mnt_kern_flag |= MNTK_VGONE_UPPER; 2670 for (ump = TAILQ_FIRST(&mp->mnt_uppers); ump != NULL;) { 2671 if ((ump->mnt_kern_flag & MNTK_MARKER) != 0) { 2672 ump = TAILQ_NEXT(ump, mnt_upper_link); 2673 continue; 2674 } 2675 TAILQ_INSERT_AFTER(&mp->mnt_uppers, ump, mmp, mnt_upper_link); 2676 MNT_IUNLOCK(mp); 2677 switch (event) { 2678 case VFS_NOTIFY_UPPER_RECLAIM: 2679 VFS_RECLAIM_LOWERVP(ump, vp); 2680 break; 2681 case VFS_NOTIFY_UPPER_UNLINK: 2682 VFS_UNLINK_LOWERVP(ump, vp); 2683 break; 2684 default: 2685 KASSERT(0, ("invalid event %d", event)); 2686 break; 2687 } 2688 MNT_ILOCK(mp); 2689 ump = TAILQ_NEXT(mmp, mnt_upper_link); 2690 TAILQ_REMOVE(&mp->mnt_uppers, mmp, mnt_upper_link); 2691 } 2692 free(mmp, M_TEMP); 2693 mp->mnt_kern_flag &= ~MNTK_VGONE_UPPER; 2694 if ((mp->mnt_kern_flag & MNTK_VGONE_WAITER) != 0) { 2695 mp->mnt_kern_flag &= ~MNTK_VGONE_WAITER; 2696 wakeup(&mp->mnt_uppers); 2697 } 2698 unlock: 2699 MNT_IUNLOCK(mp); 2700 } 2701 2702 /* 2703 * vgone, with the vp interlock held. 2704 */ 2705 void 2706 vgonel(struct vnode *vp) 2707 { 2708 struct thread *td; 2709 int oweinact; 2710 int active; 2711 struct mount *mp; 2712 2713 ASSERT_VOP_ELOCKED(vp, "vgonel"); 2714 ASSERT_VI_LOCKED(vp, "vgonel"); 2715 VNASSERT(vp->v_holdcnt, vp, 2716 ("vgonel: vp %p has no reference.", vp)); 2717 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2718 td = curthread; 2719 2720 /* 2721 * Don't vgonel if we're already doomed. 2722 */ 2723 if (vp->v_iflag & VI_DOOMED) 2724 return; 2725 vp->v_iflag |= VI_DOOMED; 2726 2727 /* 2728 * Check to see if the vnode is in use. If so, we have to call 2729 * VOP_CLOSE() and VOP_INACTIVE(). 2730 */ 2731 active = vp->v_usecount; 2732 oweinact = (vp->v_iflag & VI_OWEINACT); 2733 VI_UNLOCK(vp); 2734 vfs_notify_upper(vp, VFS_NOTIFY_UPPER_RECLAIM); 2735 2736 /* 2737 * Clean out any buffers associated with the vnode. 2738 * If the flush fails, just toss the buffers. 2739 */ 2740 mp = NULL; 2741 if (!TAILQ_EMPTY(&vp->v_bufobj.bo_dirty.bv_hd)) 2742 (void) vn_start_secondary_write(vp, &mp, V_WAIT); 2743 if (vinvalbuf(vp, V_SAVE, 0, 0) != 0) 2744 vinvalbuf(vp, 0, 0, 0); 2745 2746 /* 2747 * If purging an active vnode, it must be closed and 2748 * deactivated before being reclaimed. 2749 */ 2750 if (active) 2751 VOP_CLOSE(vp, FNONBLOCK, NOCRED, td); 2752 if (oweinact || active) { 2753 VI_LOCK(vp); 2754 if ((vp->v_iflag & VI_DOINGINACT) == 0) 2755 vinactive(vp, td); 2756 VI_UNLOCK(vp); 2757 } 2758 if (vp->v_type == VSOCK) 2759 vfs_unp_reclaim(vp); 2760 /* 2761 * Reclaim the vnode. 2762 */ 2763 if (VOP_RECLAIM(vp, td)) 2764 panic("vgone: cannot reclaim"); 2765 if (mp != NULL) 2766 vn_finished_secondary_write(mp); 2767 VNASSERT(vp->v_object == NULL, vp, 2768 ("vop_reclaim left v_object vp=%p, tag=%s", vp, vp->v_tag)); 2769 /* 2770 * Clear the advisory locks and wake up waiting threads. 2771 */ 2772 (void)VOP_ADVLOCKPURGE(vp); 2773 /* 2774 * Delete from old mount point vnode list. 2775 */ 2776 delmntque(vp); 2777 cache_purge(vp); 2778 /* 2779 * Done with purge, reset to the standard lock and invalidate 2780 * the vnode. 2781 */ 2782 VI_LOCK(vp); 2783 vp->v_vnlock = &vp->v_lock; 2784 vp->v_op = &dead_vnodeops; 2785 vp->v_tag = "none"; 2786 vp->v_type = VBAD; 2787 } 2788 2789 /* 2790 * Calculate the total number of references to a special device. 2791 */ 2792 int 2793 vcount(struct vnode *vp) 2794 { 2795 int count; 2796 2797 dev_lock(); 2798 count = vp->v_rdev->si_usecount; 2799 dev_unlock(); 2800 return (count); 2801 } 2802 2803 /* 2804 * Same as above, but using the struct cdev *as argument 2805 */ 2806 int 2807 count_dev(struct cdev *dev) 2808 { 2809 int count; 2810 2811 dev_lock(); 2812 count = dev->si_usecount; 2813 dev_unlock(); 2814 return(count); 2815 } 2816 2817 /* 2818 * Print out a description of a vnode. 2819 */ 2820 static char *typename[] = 2821 {"VNON", "VREG", "VDIR", "VBLK", "VCHR", "VLNK", "VSOCK", "VFIFO", "VBAD", 2822 "VMARKER"}; 2823 2824 void 2825 vn_printf(struct vnode *vp, const char *fmt, ...) 2826 { 2827 va_list ap; 2828 char buf[256], buf2[16]; 2829 u_long flags; 2830 2831 va_start(ap, fmt); 2832 vprintf(fmt, ap); 2833 va_end(ap); 2834 printf("%p: ", (void *)vp); 2835 printf("tag %s, type %s\n", vp->v_tag, typename[vp->v_type]); 2836 printf(" usecount %d, writecount %d, refcount %d mountedhere %p\n", 2837 vp->v_usecount, vp->v_writecount, vp->v_holdcnt, vp->v_mountedhere); 2838 buf[0] = '\0'; 2839 buf[1] = '\0'; 2840 if (vp->v_vflag & VV_ROOT) 2841 strlcat(buf, "|VV_ROOT", sizeof(buf)); 2842 if (vp->v_vflag & VV_ISTTY) 2843 strlcat(buf, "|VV_ISTTY", sizeof(buf)); 2844 if (vp->v_vflag & VV_NOSYNC) 2845 strlcat(buf, "|VV_NOSYNC", sizeof(buf)); 2846 if (vp->v_vflag & VV_ETERNALDEV) 2847 strlcat(buf, "|VV_ETERNALDEV", sizeof(buf)); 2848 if (vp->v_vflag & VV_CACHEDLABEL) 2849 strlcat(buf, "|VV_CACHEDLABEL", sizeof(buf)); 2850 if (vp->v_vflag & VV_TEXT) 2851 strlcat(buf, "|VV_TEXT", sizeof(buf)); 2852 if (vp->v_vflag & VV_COPYONWRITE) 2853 strlcat(buf, "|VV_COPYONWRITE", sizeof(buf)); 2854 if (vp->v_vflag & VV_SYSTEM) 2855 strlcat(buf, "|VV_SYSTEM", sizeof(buf)); 2856 if (vp->v_vflag & VV_PROCDEP) 2857 strlcat(buf, "|VV_PROCDEP", sizeof(buf)); 2858 if (vp->v_vflag & VV_NOKNOTE) 2859 strlcat(buf, "|VV_NOKNOTE", sizeof(buf)); 2860 if (vp->v_vflag & VV_DELETED) 2861 strlcat(buf, "|VV_DELETED", sizeof(buf)); 2862 if (vp->v_vflag & VV_MD) 2863 strlcat(buf, "|VV_MD", sizeof(buf)); 2864 if (vp->v_vflag & VV_FORCEINSMQ) 2865 strlcat(buf, "|VV_FORCEINSMQ", sizeof(buf)); 2866 flags = vp->v_vflag & ~(VV_ROOT | VV_ISTTY | VV_NOSYNC | VV_ETERNALDEV | 2867 VV_CACHEDLABEL | VV_TEXT | VV_COPYONWRITE | VV_SYSTEM | VV_PROCDEP | 2868 VV_NOKNOTE | VV_DELETED | VV_MD | VV_FORCEINSMQ); 2869 if (flags != 0) { 2870 snprintf(buf2, sizeof(buf2), "|VV(0x%lx)", flags); 2871 strlcat(buf, buf2, sizeof(buf)); 2872 } 2873 if (vp->v_iflag & VI_MOUNT) 2874 strlcat(buf, "|VI_MOUNT", sizeof(buf)); 2875 if (vp->v_iflag & VI_AGE) 2876 strlcat(buf, "|VI_AGE", sizeof(buf)); 2877 if (vp->v_iflag & VI_DOOMED) 2878 strlcat(buf, "|VI_DOOMED", sizeof(buf)); 2879 if (vp->v_iflag & VI_FREE) 2880 strlcat(buf, "|VI_FREE", sizeof(buf)); 2881 if (vp->v_iflag & VI_ACTIVE) 2882 strlcat(buf, "|VI_ACTIVE", sizeof(buf)); 2883 if (vp->v_iflag & VI_DOINGINACT) 2884 strlcat(buf, "|VI_DOINGINACT", sizeof(buf)); 2885 if (vp->v_iflag & VI_OWEINACT) 2886 strlcat(buf, "|VI_OWEINACT", sizeof(buf)); 2887 flags = vp->v_iflag & ~(VI_MOUNT | VI_AGE | VI_DOOMED | VI_FREE | 2888 VI_ACTIVE | VI_DOINGINACT | VI_OWEINACT); 2889 if (flags != 0) { 2890 snprintf(buf2, sizeof(buf2), "|VI(0x%lx)", flags); 2891 strlcat(buf, buf2, sizeof(buf)); 2892 } 2893 printf(" flags (%s)\n", buf + 1); 2894 if (mtx_owned(VI_MTX(vp))) 2895 printf(" VI_LOCKed"); 2896 if (vp->v_object != NULL) 2897 printf(" v_object %p ref %d pages %d " 2898 "cleanbuf %d dirtybuf %d\n", 2899 vp->v_object, vp->v_object->ref_count, 2900 vp->v_object->resident_page_count, 2901 vp->v_bufobj.bo_dirty.bv_cnt, 2902 vp->v_bufobj.bo_clean.bv_cnt); 2903 printf(" "); 2904 lockmgr_printinfo(vp->v_vnlock); 2905 if (vp->v_data != NULL) 2906 VOP_PRINT(vp); 2907 } 2908 2909 #ifdef DDB 2910 /* 2911 * List all of the locked vnodes in the system. 2912 * Called when debugging the kernel. 2913 */ 2914 DB_SHOW_COMMAND(lockedvnods, lockedvnodes) 2915 { 2916 struct mount *mp; 2917 struct vnode *vp; 2918 2919 /* 2920 * Note: because this is DDB, we can't obey the locking semantics 2921 * for these structures, which means we could catch an inconsistent 2922 * state and dereference a nasty pointer. Not much to be done 2923 * about that. 2924 */ 2925 db_printf("Locked vnodes\n"); 2926 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 2927 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) { 2928 if (vp->v_type != VMARKER && VOP_ISLOCKED(vp)) 2929 vprint("", vp); 2930 } 2931 } 2932 } 2933 2934 /* 2935 * Show details about the given vnode. 2936 */ 2937 DB_SHOW_COMMAND(vnode, db_show_vnode) 2938 { 2939 struct vnode *vp; 2940 2941 if (!have_addr) 2942 return; 2943 vp = (struct vnode *)addr; 2944 vn_printf(vp, "vnode "); 2945 } 2946 2947 /* 2948 * Show details about the given mount point. 2949 */ 2950 DB_SHOW_COMMAND(mount, db_show_mount) 2951 { 2952 struct mount *mp; 2953 struct vfsopt *opt; 2954 struct statfs *sp; 2955 struct vnode *vp; 2956 char buf[512]; 2957 uint64_t mflags; 2958 u_int flags; 2959 2960 if (!have_addr) { 2961 /* No address given, print short info about all mount points. */ 2962 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 2963 db_printf("%p %s on %s (%s)\n", mp, 2964 mp->mnt_stat.f_mntfromname, 2965 mp->mnt_stat.f_mntonname, 2966 mp->mnt_stat.f_fstypename); 2967 if (db_pager_quit) 2968 break; 2969 } 2970 db_printf("\nMore info: show mount <addr>\n"); 2971 return; 2972 } 2973 2974 mp = (struct mount *)addr; 2975 db_printf("%p %s on %s (%s)\n", mp, mp->mnt_stat.f_mntfromname, 2976 mp->mnt_stat.f_mntonname, mp->mnt_stat.f_fstypename); 2977 2978 buf[0] = '\0'; 2979 mflags = mp->mnt_flag; 2980 #define MNT_FLAG(flag) do { \ 2981 if (mflags & (flag)) { \ 2982 if (buf[0] != '\0') \ 2983 strlcat(buf, ", ", sizeof(buf)); \ 2984 strlcat(buf, (#flag) + 4, sizeof(buf)); \ 2985 mflags &= ~(flag); \ 2986 } \ 2987 } while (0) 2988 MNT_FLAG(MNT_RDONLY); 2989 MNT_FLAG(MNT_SYNCHRONOUS); 2990 MNT_FLAG(MNT_NOEXEC); 2991 MNT_FLAG(MNT_NOSUID); 2992 MNT_FLAG(MNT_NFS4ACLS); 2993 MNT_FLAG(MNT_UNION); 2994 MNT_FLAG(MNT_ASYNC); 2995 MNT_FLAG(MNT_SUIDDIR); 2996 MNT_FLAG(MNT_SOFTDEP); 2997 MNT_FLAG(MNT_NOSYMFOLLOW); 2998 MNT_FLAG(MNT_GJOURNAL); 2999 MNT_FLAG(MNT_MULTILABEL); 3000 MNT_FLAG(MNT_ACLS); 3001 MNT_FLAG(MNT_NOATIME); 3002 MNT_FLAG(MNT_NOCLUSTERR); 3003 MNT_FLAG(MNT_NOCLUSTERW); 3004 MNT_FLAG(MNT_SUJ); 3005 MNT_FLAG(MNT_EXRDONLY); 3006 MNT_FLAG(MNT_EXPORTED); 3007 MNT_FLAG(MNT_DEFEXPORTED); 3008 MNT_FLAG(MNT_EXPORTANON); 3009 MNT_FLAG(MNT_EXKERB); 3010 MNT_FLAG(MNT_EXPUBLIC); 3011 MNT_FLAG(MNT_LOCAL); 3012 MNT_FLAG(MNT_QUOTA); 3013 MNT_FLAG(MNT_ROOTFS); 3014 MNT_FLAG(MNT_USER); 3015 MNT_FLAG(MNT_IGNORE); 3016 MNT_FLAG(MNT_UPDATE); 3017 MNT_FLAG(MNT_DELEXPORT); 3018 MNT_FLAG(MNT_RELOAD); 3019 MNT_FLAG(MNT_FORCE); 3020 MNT_FLAG(MNT_SNAPSHOT); 3021 MNT_FLAG(MNT_BYFSID); 3022 #undef MNT_FLAG 3023 if (mflags != 0) { 3024 if (buf[0] != '\0') 3025 strlcat(buf, ", ", sizeof(buf)); 3026 snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf), 3027 "0x%016jx", mflags); 3028 } 3029 db_printf(" mnt_flag = %s\n", buf); 3030 3031 buf[0] = '\0'; 3032 flags = mp->mnt_kern_flag; 3033 #define MNT_KERN_FLAG(flag) do { \ 3034 if (flags & (flag)) { \ 3035 if (buf[0] != '\0') \ 3036 strlcat(buf, ", ", sizeof(buf)); \ 3037 strlcat(buf, (#flag) + 5, sizeof(buf)); \ 3038 flags &= ~(flag); \ 3039 } \ 3040 } while (0) 3041 MNT_KERN_FLAG(MNTK_UNMOUNTF); 3042 MNT_KERN_FLAG(MNTK_ASYNC); 3043 MNT_KERN_FLAG(MNTK_SOFTDEP); 3044 MNT_KERN_FLAG(MNTK_NOINSMNTQ); 3045 MNT_KERN_FLAG(MNTK_DRAINING); 3046 MNT_KERN_FLAG(MNTK_REFEXPIRE); 3047 MNT_KERN_FLAG(MNTK_EXTENDED_SHARED); 3048 MNT_KERN_FLAG(MNTK_SHARED_WRITES); 3049 MNT_KERN_FLAG(MNTK_NO_IOPF); 3050 MNT_KERN_FLAG(MNTK_VGONE_UPPER); 3051 MNT_KERN_FLAG(MNTK_VGONE_WAITER); 3052 MNT_KERN_FLAG(MNTK_LOOKUP_EXCL_DOTDOT); 3053 MNT_KERN_FLAG(MNTK_MARKER); 3054 MNT_KERN_FLAG(MNTK_NOASYNC); 3055 MNT_KERN_FLAG(MNTK_UNMOUNT); 3056 MNT_KERN_FLAG(MNTK_MWAIT); 3057 MNT_KERN_FLAG(MNTK_SUSPEND); 3058 MNT_KERN_FLAG(MNTK_SUSPEND2); 3059 MNT_KERN_FLAG(MNTK_SUSPENDED); 3060 MNT_KERN_FLAG(MNTK_LOOKUP_SHARED); 3061 MNT_KERN_FLAG(MNTK_NOKNOTE); 3062 #undef MNT_KERN_FLAG 3063 if (flags != 0) { 3064 if (buf[0] != '\0') 3065 strlcat(buf, ", ", sizeof(buf)); 3066 snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf), 3067 "0x%08x", flags); 3068 } 3069 db_printf(" mnt_kern_flag = %s\n", buf); 3070 3071 db_printf(" mnt_opt = "); 3072 opt = TAILQ_FIRST(mp->mnt_opt); 3073 if (opt != NULL) { 3074 db_printf("%s", opt->name); 3075 opt = TAILQ_NEXT(opt, link); 3076 while (opt != NULL) { 3077 db_printf(", %s", opt->name); 3078 opt = TAILQ_NEXT(opt, link); 3079 } 3080 } 3081 db_printf("\n"); 3082 3083 sp = &mp->mnt_stat; 3084 db_printf(" mnt_stat = { version=%u type=%u flags=0x%016jx " 3085 "bsize=%ju iosize=%ju blocks=%ju bfree=%ju bavail=%jd files=%ju " 3086 "ffree=%jd syncwrites=%ju asyncwrites=%ju syncreads=%ju " 3087 "asyncreads=%ju namemax=%u owner=%u fsid=[%d, %d] }\n", 3088 (u_int)sp->f_version, (u_int)sp->f_type, (uintmax_t)sp->f_flags, 3089 (uintmax_t)sp->f_bsize, (uintmax_t)sp->f_iosize, 3090 (uintmax_t)sp->f_blocks, (uintmax_t)sp->f_bfree, 3091 (intmax_t)sp->f_bavail, (uintmax_t)sp->f_files, 3092 (intmax_t)sp->f_ffree, (uintmax_t)sp->f_syncwrites, 3093 (uintmax_t)sp->f_asyncwrites, (uintmax_t)sp->f_syncreads, 3094 (uintmax_t)sp->f_asyncreads, (u_int)sp->f_namemax, 3095 (u_int)sp->f_owner, (int)sp->f_fsid.val[0], (int)sp->f_fsid.val[1]); 3096 3097 db_printf(" mnt_cred = { uid=%u ruid=%u", 3098 (u_int)mp->mnt_cred->cr_uid, (u_int)mp->mnt_cred->cr_ruid); 3099 if (jailed(mp->mnt_cred)) 3100 db_printf(", jail=%d", mp->mnt_cred->cr_prison->pr_id); 3101 db_printf(" }\n"); 3102 db_printf(" mnt_ref = %d\n", mp->mnt_ref); 3103 db_printf(" mnt_gen = %d\n", mp->mnt_gen); 3104 db_printf(" mnt_nvnodelistsize = %d\n", mp->mnt_nvnodelistsize); 3105 db_printf(" mnt_activevnodelistsize = %d\n", 3106 mp->mnt_activevnodelistsize); 3107 db_printf(" mnt_writeopcount = %d\n", mp->mnt_writeopcount); 3108 db_printf(" mnt_maxsymlinklen = %d\n", mp->mnt_maxsymlinklen); 3109 db_printf(" mnt_iosize_max = %d\n", mp->mnt_iosize_max); 3110 db_printf(" mnt_hashseed = %u\n", mp->mnt_hashseed); 3111 db_printf(" mnt_secondary_writes = %d\n", mp->mnt_secondary_writes); 3112 db_printf(" mnt_secondary_accwrites = %d\n", 3113 mp->mnt_secondary_accwrites); 3114 db_printf(" mnt_gjprovider = %s\n", 3115 mp->mnt_gjprovider != NULL ? mp->mnt_gjprovider : "NULL"); 3116 3117 db_printf("\n\nList of active vnodes\n"); 3118 TAILQ_FOREACH(vp, &mp->mnt_activevnodelist, v_actfreelist) { 3119 if (vp->v_type != VMARKER) { 3120 vn_printf(vp, "vnode "); 3121 if (db_pager_quit) 3122 break; 3123 } 3124 } 3125 db_printf("\n\nList of inactive vnodes\n"); 3126 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) { 3127 if (vp->v_type != VMARKER && (vp->v_iflag & VI_ACTIVE) == 0) { 3128 vn_printf(vp, "vnode "); 3129 if (db_pager_quit) 3130 break; 3131 } 3132 } 3133 } 3134 #endif /* DDB */ 3135 3136 /* 3137 * Fill in a struct xvfsconf based on a struct vfsconf. 3138 */ 3139 static int 3140 vfsconf2x(struct sysctl_req *req, struct vfsconf *vfsp) 3141 { 3142 struct xvfsconf xvfsp; 3143 3144 bzero(&xvfsp, sizeof(xvfsp)); 3145 strcpy(xvfsp.vfc_name, vfsp->vfc_name); 3146 xvfsp.vfc_typenum = vfsp->vfc_typenum; 3147 xvfsp.vfc_refcount = vfsp->vfc_refcount; 3148 xvfsp.vfc_flags = vfsp->vfc_flags; 3149 /* 3150 * These are unused in userland, we keep them 3151 * to not break binary compatibility. 3152 */ 3153 xvfsp.vfc_vfsops = NULL; 3154 xvfsp.vfc_next = NULL; 3155 return (SYSCTL_OUT(req, &xvfsp, sizeof(xvfsp))); 3156 } 3157 3158 #ifdef COMPAT_FREEBSD32 3159 struct xvfsconf32 { 3160 uint32_t vfc_vfsops; 3161 char vfc_name[MFSNAMELEN]; 3162 int32_t vfc_typenum; 3163 int32_t vfc_refcount; 3164 int32_t vfc_flags; 3165 uint32_t vfc_next; 3166 }; 3167 3168 static int 3169 vfsconf2x32(struct sysctl_req *req, struct vfsconf *vfsp) 3170 { 3171 struct xvfsconf32 xvfsp; 3172 3173 strcpy(xvfsp.vfc_name, vfsp->vfc_name); 3174 xvfsp.vfc_typenum = vfsp->vfc_typenum; 3175 xvfsp.vfc_refcount = vfsp->vfc_refcount; 3176 xvfsp.vfc_flags = vfsp->vfc_flags; 3177 xvfsp.vfc_vfsops = 0; 3178 xvfsp.vfc_next = 0; 3179 return (SYSCTL_OUT(req, &xvfsp, sizeof(xvfsp))); 3180 } 3181 #endif 3182 3183 /* 3184 * Top level filesystem related information gathering. 3185 */ 3186 static int 3187 sysctl_vfs_conflist(SYSCTL_HANDLER_ARGS) 3188 { 3189 struct vfsconf *vfsp; 3190 int error; 3191 3192 error = 0; 3193 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) { 3194 #ifdef COMPAT_FREEBSD32 3195 if (req->flags & SCTL_MASK32) 3196 error = vfsconf2x32(req, vfsp); 3197 else 3198 #endif 3199 error = vfsconf2x(req, vfsp); 3200 if (error) 3201 break; 3202 } 3203 return (error); 3204 } 3205 3206 SYSCTL_PROC(_vfs, OID_AUTO, conflist, CTLTYPE_OPAQUE | CTLFLAG_RD, 3207 NULL, 0, sysctl_vfs_conflist, 3208 "S,xvfsconf", "List of all configured filesystems"); 3209 3210 #ifndef BURN_BRIDGES 3211 static int sysctl_ovfs_conf(SYSCTL_HANDLER_ARGS); 3212 3213 static int 3214 vfs_sysctl(SYSCTL_HANDLER_ARGS) 3215 { 3216 int *name = (int *)arg1 - 1; /* XXX */ 3217 u_int namelen = arg2 + 1; /* XXX */ 3218 struct vfsconf *vfsp; 3219 3220 log(LOG_WARNING, "userland calling deprecated sysctl, " 3221 "please rebuild world\n"); 3222 3223 #if 1 || defined(COMPAT_PRELITE2) 3224 /* Resolve ambiguity between VFS_VFSCONF and VFS_GENERIC. */ 3225 if (namelen == 1) 3226 return (sysctl_ovfs_conf(oidp, arg1, arg2, req)); 3227 #endif 3228 3229 switch (name[1]) { 3230 case VFS_MAXTYPENUM: 3231 if (namelen != 2) 3232 return (ENOTDIR); 3233 return (SYSCTL_OUT(req, &maxvfsconf, sizeof(int))); 3234 case VFS_CONF: 3235 if (namelen != 3) 3236 return (ENOTDIR); /* overloaded */ 3237 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) 3238 if (vfsp->vfc_typenum == name[2]) 3239 break; 3240 if (vfsp == NULL) 3241 return (EOPNOTSUPP); 3242 #ifdef COMPAT_FREEBSD32 3243 if (req->flags & SCTL_MASK32) 3244 return (vfsconf2x32(req, vfsp)); 3245 else 3246 #endif 3247 return (vfsconf2x(req, vfsp)); 3248 } 3249 return (EOPNOTSUPP); 3250 } 3251 3252 static SYSCTL_NODE(_vfs, VFS_GENERIC, generic, CTLFLAG_RD | CTLFLAG_SKIP, 3253 vfs_sysctl, "Generic filesystem"); 3254 3255 #if 1 || defined(COMPAT_PRELITE2) 3256 3257 static int 3258 sysctl_ovfs_conf(SYSCTL_HANDLER_ARGS) 3259 { 3260 int error; 3261 struct vfsconf *vfsp; 3262 struct ovfsconf ovfs; 3263 3264 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) { 3265 bzero(&ovfs, sizeof(ovfs)); 3266 ovfs.vfc_vfsops = vfsp->vfc_vfsops; /* XXX used as flag */ 3267 strcpy(ovfs.vfc_name, vfsp->vfc_name); 3268 ovfs.vfc_index = vfsp->vfc_typenum; 3269 ovfs.vfc_refcount = vfsp->vfc_refcount; 3270 ovfs.vfc_flags = vfsp->vfc_flags; 3271 error = SYSCTL_OUT(req, &ovfs, sizeof ovfs); 3272 if (error) 3273 return error; 3274 } 3275 return 0; 3276 } 3277 3278 #endif /* 1 || COMPAT_PRELITE2 */ 3279 #endif /* !BURN_BRIDGES */ 3280 3281 #define KINFO_VNODESLOP 10 3282 #ifdef notyet 3283 /* 3284 * Dump vnode list (via sysctl). 3285 */ 3286 /* ARGSUSED */ 3287 static int 3288 sysctl_vnode(SYSCTL_HANDLER_ARGS) 3289 { 3290 struct xvnode *xvn; 3291 struct mount *mp; 3292 struct vnode *vp; 3293 int error, len, n; 3294 3295 /* 3296 * Stale numvnodes access is not fatal here. 3297 */ 3298 req->lock = 0; 3299 len = (numvnodes + KINFO_VNODESLOP) * sizeof *xvn; 3300 if (!req->oldptr) 3301 /* Make an estimate */ 3302 return (SYSCTL_OUT(req, 0, len)); 3303 3304 error = sysctl_wire_old_buffer(req, 0); 3305 if (error != 0) 3306 return (error); 3307 xvn = malloc(len, M_TEMP, M_ZERO | M_WAITOK); 3308 n = 0; 3309 mtx_lock(&mountlist_mtx); 3310 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 3311 if (vfs_busy(mp, MBF_NOWAIT | MBF_MNTLSTLOCK)) 3312 continue; 3313 MNT_ILOCK(mp); 3314 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) { 3315 if (n == len) 3316 break; 3317 vref(vp); 3318 xvn[n].xv_size = sizeof *xvn; 3319 xvn[n].xv_vnode = vp; 3320 xvn[n].xv_id = 0; /* XXX compat */ 3321 #define XV_COPY(field) xvn[n].xv_##field = vp->v_##field 3322 XV_COPY(usecount); 3323 XV_COPY(writecount); 3324 XV_COPY(holdcnt); 3325 XV_COPY(mount); 3326 XV_COPY(numoutput); 3327 XV_COPY(type); 3328 #undef XV_COPY 3329 xvn[n].xv_flag = vp->v_vflag; 3330 3331 switch (vp->v_type) { 3332 case VREG: 3333 case VDIR: 3334 case VLNK: 3335 break; 3336 case VBLK: 3337 case VCHR: 3338 if (vp->v_rdev == NULL) { 3339 vrele(vp); 3340 continue; 3341 } 3342 xvn[n].xv_dev = dev2udev(vp->v_rdev); 3343 break; 3344 case VSOCK: 3345 xvn[n].xv_socket = vp->v_socket; 3346 break; 3347 case VFIFO: 3348 xvn[n].xv_fifo = vp->v_fifoinfo; 3349 break; 3350 case VNON: 3351 case VBAD: 3352 default: 3353 /* shouldn't happen? */ 3354 vrele(vp); 3355 continue; 3356 } 3357 vrele(vp); 3358 ++n; 3359 } 3360 MNT_IUNLOCK(mp); 3361 mtx_lock(&mountlist_mtx); 3362 vfs_unbusy(mp); 3363 if (n == len) 3364 break; 3365 } 3366 mtx_unlock(&mountlist_mtx); 3367 3368 error = SYSCTL_OUT(req, xvn, n * sizeof *xvn); 3369 free(xvn, M_TEMP); 3370 return (error); 3371 } 3372 3373 SYSCTL_PROC(_kern, KERN_VNODE, vnode, CTLTYPE_OPAQUE|CTLFLAG_RD, 3374 0, 0, sysctl_vnode, "S,xvnode", ""); 3375 #endif 3376 3377 /* 3378 * Unmount all filesystems. The list is traversed in reverse order 3379 * of mounting to avoid dependencies. 3380 */ 3381 void 3382 vfs_unmountall(void) 3383 { 3384 struct mount *mp; 3385 struct thread *td; 3386 int error; 3387 3388 CTR1(KTR_VFS, "%s: unmounting all filesystems", __func__); 3389 td = curthread; 3390 3391 /* 3392 * Since this only runs when rebooting, it is not interlocked. 3393 */ 3394 while(!TAILQ_EMPTY(&mountlist)) { 3395 mp = TAILQ_LAST(&mountlist, mntlist); 3396 error = dounmount(mp, MNT_FORCE, td); 3397 if (error) { 3398 TAILQ_REMOVE(&mountlist, mp, mnt_list); 3399 /* 3400 * XXX: Due to the way in which we mount the root 3401 * file system off of devfs, devfs will generate a 3402 * "busy" warning when we try to unmount it before 3403 * the root. Don't print a warning as a result in 3404 * order to avoid false positive errors that may 3405 * cause needless upset. 3406 */ 3407 if (strcmp(mp->mnt_vfc->vfc_name, "devfs") != 0) { 3408 printf("unmount of %s failed (", 3409 mp->mnt_stat.f_mntonname); 3410 if (error == EBUSY) 3411 printf("BUSY)\n"); 3412 else 3413 printf("%d)\n", error); 3414 } 3415 } else { 3416 /* The unmount has removed mp from the mountlist */ 3417 } 3418 } 3419 } 3420 3421 /* 3422 * perform msync on all vnodes under a mount point 3423 * the mount point must be locked. 3424 */ 3425 void 3426 vfs_msync(struct mount *mp, int flags) 3427 { 3428 struct vnode *vp, *mvp; 3429 struct vm_object *obj; 3430 3431 CTR2(KTR_VFS, "%s: mp %p", __func__, mp); 3432 MNT_VNODE_FOREACH_ACTIVE(vp, mp, mvp) { 3433 obj = vp->v_object; 3434 if (obj != NULL && (obj->flags & OBJ_MIGHTBEDIRTY) != 0 && 3435 (flags == MNT_WAIT || VOP_ISLOCKED(vp) == 0)) { 3436 if (!vget(vp, 3437 LK_EXCLUSIVE | LK_RETRY | LK_INTERLOCK, 3438 curthread)) { 3439 if (vp->v_vflag & VV_NOSYNC) { /* unlinked */ 3440 vput(vp); 3441 continue; 3442 } 3443 3444 obj = vp->v_object; 3445 if (obj != NULL) { 3446 VM_OBJECT_WLOCK(obj); 3447 vm_object_page_clean(obj, 0, 0, 3448 flags == MNT_WAIT ? 3449 OBJPC_SYNC : OBJPC_NOSYNC); 3450 VM_OBJECT_WUNLOCK(obj); 3451 } 3452 vput(vp); 3453 } 3454 } else 3455 VI_UNLOCK(vp); 3456 } 3457 } 3458 3459 static void 3460 destroy_vpollinfo_free(struct vpollinfo *vi) 3461 { 3462 3463 knlist_destroy(&vi->vpi_selinfo.si_note); 3464 mtx_destroy(&vi->vpi_lock); 3465 uma_zfree(vnodepoll_zone, vi); 3466 } 3467 3468 static void 3469 destroy_vpollinfo(struct vpollinfo *vi) 3470 { 3471 3472 knlist_clear(&vi->vpi_selinfo.si_note, 1); 3473 seldrain(&vi->vpi_selinfo); 3474 destroy_vpollinfo_free(vi); 3475 } 3476 3477 /* 3478 * Initalize per-vnode helper structure to hold poll-related state. 3479 */ 3480 void 3481 v_addpollinfo(struct vnode *vp) 3482 { 3483 struct vpollinfo *vi; 3484 3485 if (vp->v_pollinfo != NULL) 3486 return; 3487 vi = uma_zalloc(vnodepoll_zone, M_WAITOK); 3488 mtx_init(&vi->vpi_lock, "vnode pollinfo", NULL, MTX_DEF); 3489 knlist_init(&vi->vpi_selinfo.si_note, vp, vfs_knllock, 3490 vfs_knlunlock, vfs_knl_assert_locked, vfs_knl_assert_unlocked); 3491 VI_LOCK(vp); 3492 if (vp->v_pollinfo != NULL) { 3493 VI_UNLOCK(vp); 3494 destroy_vpollinfo_free(vi); 3495 return; 3496 } 3497 vp->v_pollinfo = vi; 3498 VI_UNLOCK(vp); 3499 } 3500 3501 /* 3502 * Record a process's interest in events which might happen to 3503 * a vnode. Because poll uses the historic select-style interface 3504 * internally, this routine serves as both the ``check for any 3505 * pending events'' and the ``record my interest in future events'' 3506 * functions. (These are done together, while the lock is held, 3507 * to avoid race conditions.) 3508 */ 3509 int 3510 vn_pollrecord(struct vnode *vp, struct thread *td, int events) 3511 { 3512 3513 v_addpollinfo(vp); 3514 mtx_lock(&vp->v_pollinfo->vpi_lock); 3515 if (vp->v_pollinfo->vpi_revents & events) { 3516 /* 3517 * This leaves events we are not interested 3518 * in available for the other process which 3519 * which presumably had requested them 3520 * (otherwise they would never have been 3521 * recorded). 3522 */ 3523 events &= vp->v_pollinfo->vpi_revents; 3524 vp->v_pollinfo->vpi_revents &= ~events; 3525 3526 mtx_unlock(&vp->v_pollinfo->vpi_lock); 3527 return (events); 3528 } 3529 vp->v_pollinfo->vpi_events |= events; 3530 selrecord(td, &vp->v_pollinfo->vpi_selinfo); 3531 mtx_unlock(&vp->v_pollinfo->vpi_lock); 3532 return (0); 3533 } 3534 3535 /* 3536 * Routine to create and manage a filesystem syncer vnode. 3537 */ 3538 #define sync_close ((int (*)(struct vop_close_args *))nullop) 3539 static int sync_fsync(struct vop_fsync_args *); 3540 static int sync_inactive(struct vop_inactive_args *); 3541 static int sync_reclaim(struct vop_reclaim_args *); 3542 3543 static struct vop_vector sync_vnodeops = { 3544 .vop_bypass = VOP_EOPNOTSUPP, 3545 .vop_close = sync_close, /* close */ 3546 .vop_fsync = sync_fsync, /* fsync */ 3547 .vop_inactive = sync_inactive, /* inactive */ 3548 .vop_reclaim = sync_reclaim, /* reclaim */ 3549 .vop_lock1 = vop_stdlock, /* lock */ 3550 .vop_unlock = vop_stdunlock, /* unlock */ 3551 .vop_islocked = vop_stdislocked, /* islocked */ 3552 }; 3553 3554 /* 3555 * Create a new filesystem syncer vnode for the specified mount point. 3556 */ 3557 void 3558 vfs_allocate_syncvnode(struct mount *mp) 3559 { 3560 struct vnode *vp; 3561 struct bufobj *bo; 3562 static long start, incr, next; 3563 int error; 3564 3565 /* Allocate a new vnode */ 3566 error = getnewvnode("syncer", mp, &sync_vnodeops, &vp); 3567 if (error != 0) 3568 panic("vfs_allocate_syncvnode: getnewvnode() failed"); 3569 vp->v_type = VNON; 3570 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 3571 vp->v_vflag |= VV_FORCEINSMQ; 3572 error = insmntque(vp, mp); 3573 if (error != 0) 3574 panic("vfs_allocate_syncvnode: insmntque() failed"); 3575 vp->v_vflag &= ~VV_FORCEINSMQ; 3576 VOP_UNLOCK(vp, 0); 3577 /* 3578 * Place the vnode onto the syncer worklist. We attempt to 3579 * scatter them about on the list so that they will go off 3580 * at evenly distributed times even if all the filesystems 3581 * are mounted at once. 3582 */ 3583 next += incr; 3584 if (next == 0 || next > syncer_maxdelay) { 3585 start /= 2; 3586 incr /= 2; 3587 if (start == 0) { 3588 start = syncer_maxdelay / 2; 3589 incr = syncer_maxdelay; 3590 } 3591 next = start; 3592 } 3593 bo = &vp->v_bufobj; 3594 BO_LOCK(bo); 3595 vn_syncer_add_to_worklist(bo, syncdelay > 0 ? next % syncdelay : 0); 3596 /* XXX - vn_syncer_add_to_worklist() also grabs and drops sync_mtx. */ 3597 mtx_lock(&sync_mtx); 3598 sync_vnode_count++; 3599 if (mp->mnt_syncer == NULL) { 3600 mp->mnt_syncer = vp; 3601 vp = NULL; 3602 } 3603 mtx_unlock(&sync_mtx); 3604 BO_UNLOCK(bo); 3605 if (vp != NULL) { 3606 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 3607 vgone(vp); 3608 vput(vp); 3609 } 3610 } 3611 3612 void 3613 vfs_deallocate_syncvnode(struct mount *mp) 3614 { 3615 struct vnode *vp; 3616 3617 mtx_lock(&sync_mtx); 3618 vp = mp->mnt_syncer; 3619 if (vp != NULL) 3620 mp->mnt_syncer = NULL; 3621 mtx_unlock(&sync_mtx); 3622 if (vp != NULL) 3623 vrele(vp); 3624 } 3625 3626 /* 3627 * Do a lazy sync of the filesystem. 3628 */ 3629 static int 3630 sync_fsync(struct vop_fsync_args *ap) 3631 { 3632 struct vnode *syncvp = ap->a_vp; 3633 struct mount *mp = syncvp->v_mount; 3634 int error, save; 3635 struct bufobj *bo; 3636 3637 /* 3638 * We only need to do something if this is a lazy evaluation. 3639 */ 3640 if (ap->a_waitfor != MNT_LAZY) 3641 return (0); 3642 3643 /* 3644 * Move ourselves to the back of the sync list. 3645 */ 3646 bo = &syncvp->v_bufobj; 3647 BO_LOCK(bo); 3648 vn_syncer_add_to_worklist(bo, syncdelay); 3649 BO_UNLOCK(bo); 3650 3651 /* 3652 * Walk the list of vnodes pushing all that are dirty and 3653 * not already on the sync list. 3654 */ 3655 mtx_lock(&mountlist_mtx); 3656 if (vfs_busy(mp, MBF_NOWAIT | MBF_MNTLSTLOCK) != 0) { 3657 mtx_unlock(&mountlist_mtx); 3658 return (0); 3659 } 3660 if (vn_start_write(NULL, &mp, V_NOWAIT) != 0) { 3661 vfs_unbusy(mp); 3662 return (0); 3663 } 3664 save = curthread_pflags_set(TDP_SYNCIO); 3665 vfs_msync(mp, MNT_NOWAIT); 3666 error = VFS_SYNC(mp, MNT_LAZY); 3667 curthread_pflags_restore(save); 3668 vn_finished_write(mp); 3669 vfs_unbusy(mp); 3670 return (error); 3671 } 3672 3673 /* 3674 * The syncer vnode is no referenced. 3675 */ 3676 static int 3677 sync_inactive(struct vop_inactive_args *ap) 3678 { 3679 3680 vgone(ap->a_vp); 3681 return (0); 3682 } 3683 3684 /* 3685 * The syncer vnode is no longer needed and is being decommissioned. 3686 * 3687 * Modifications to the worklist must be protected by sync_mtx. 3688 */ 3689 static int 3690 sync_reclaim(struct vop_reclaim_args *ap) 3691 { 3692 struct vnode *vp = ap->a_vp; 3693 struct bufobj *bo; 3694 3695 bo = &vp->v_bufobj; 3696 BO_LOCK(bo); 3697 mtx_lock(&sync_mtx); 3698 if (vp->v_mount->mnt_syncer == vp) 3699 vp->v_mount->mnt_syncer = NULL; 3700 if (bo->bo_flag & BO_ONWORKLST) { 3701 LIST_REMOVE(bo, bo_synclist); 3702 syncer_worklist_len--; 3703 sync_vnode_count--; 3704 bo->bo_flag &= ~BO_ONWORKLST; 3705 } 3706 mtx_unlock(&sync_mtx); 3707 BO_UNLOCK(bo); 3708 3709 return (0); 3710 } 3711 3712 /* 3713 * Check if vnode represents a disk device 3714 */ 3715 int 3716 vn_isdisk(struct vnode *vp, int *errp) 3717 { 3718 int error; 3719 3720 error = 0; 3721 dev_lock(); 3722 if (vp->v_type != VCHR) 3723 error = ENOTBLK; 3724 else if (vp->v_rdev == NULL) 3725 error = ENXIO; 3726 else if (vp->v_rdev->si_devsw == NULL) 3727 error = ENXIO; 3728 else if (!(vp->v_rdev->si_devsw->d_flags & D_DISK)) 3729 error = ENOTBLK; 3730 dev_unlock(); 3731 if (errp != NULL) 3732 *errp = error; 3733 return (error == 0); 3734 } 3735 3736 /* 3737 * Common filesystem object access control check routine. Accepts a 3738 * vnode's type, "mode", uid and gid, requested access mode, credentials, 3739 * and optional call-by-reference privused argument allowing vaccess() 3740 * to indicate to the caller whether privilege was used to satisfy the 3741 * request (obsoleted). Returns 0 on success, or an errno on failure. 3742 */ 3743 int 3744 vaccess(enum vtype type, mode_t file_mode, uid_t file_uid, gid_t file_gid, 3745 accmode_t accmode, struct ucred *cred, int *privused) 3746 { 3747 accmode_t dac_granted; 3748 accmode_t priv_granted; 3749 3750 KASSERT((accmode & ~(VEXEC | VWRITE | VREAD | VADMIN | VAPPEND)) == 0, 3751 ("invalid bit in accmode")); 3752 KASSERT((accmode & VAPPEND) == 0 || (accmode & VWRITE), 3753 ("VAPPEND without VWRITE")); 3754 3755 /* 3756 * Look for a normal, non-privileged way to access the file/directory 3757 * as requested. If it exists, go with that. 3758 */ 3759 3760 if (privused != NULL) 3761 *privused = 0; 3762 3763 dac_granted = 0; 3764 3765 /* Check the owner. */ 3766 if (cred->cr_uid == file_uid) { 3767 dac_granted |= VADMIN; 3768 if (file_mode & S_IXUSR) 3769 dac_granted |= VEXEC; 3770 if (file_mode & S_IRUSR) 3771 dac_granted |= VREAD; 3772 if (file_mode & S_IWUSR) 3773 dac_granted |= (VWRITE | VAPPEND); 3774 3775 if ((accmode & dac_granted) == accmode) 3776 return (0); 3777 3778 goto privcheck; 3779 } 3780 3781 /* Otherwise, check the groups (first match) */ 3782 if (groupmember(file_gid, cred)) { 3783 if (file_mode & S_IXGRP) 3784 dac_granted |= VEXEC; 3785 if (file_mode & S_IRGRP) 3786 dac_granted |= VREAD; 3787 if (file_mode & S_IWGRP) 3788 dac_granted |= (VWRITE | VAPPEND); 3789 3790 if ((accmode & dac_granted) == accmode) 3791 return (0); 3792 3793 goto privcheck; 3794 } 3795 3796 /* Otherwise, check everyone else. */ 3797 if (file_mode & S_IXOTH) 3798 dac_granted |= VEXEC; 3799 if (file_mode & S_IROTH) 3800 dac_granted |= VREAD; 3801 if (file_mode & S_IWOTH) 3802 dac_granted |= (VWRITE | VAPPEND); 3803 if ((accmode & dac_granted) == accmode) 3804 return (0); 3805 3806 privcheck: 3807 /* 3808 * Build a privilege mask to determine if the set of privileges 3809 * satisfies the requirements when combined with the granted mask 3810 * from above. For each privilege, if the privilege is required, 3811 * bitwise or the request type onto the priv_granted mask. 3812 */ 3813 priv_granted = 0; 3814 3815 if (type == VDIR) { 3816 /* 3817 * For directories, use PRIV_VFS_LOOKUP to satisfy VEXEC 3818 * requests, instead of PRIV_VFS_EXEC. 3819 */ 3820 if ((accmode & VEXEC) && ((dac_granted & VEXEC) == 0) && 3821 !priv_check_cred(cred, PRIV_VFS_LOOKUP, 0)) 3822 priv_granted |= VEXEC; 3823 } else { 3824 /* 3825 * Ensure that at least one execute bit is on. Otherwise, 3826 * a privileged user will always succeed, and we don't want 3827 * this to happen unless the file really is executable. 3828 */ 3829 if ((accmode & VEXEC) && ((dac_granted & VEXEC) == 0) && 3830 (file_mode & (S_IXUSR | S_IXGRP | S_IXOTH)) != 0 && 3831 !priv_check_cred(cred, PRIV_VFS_EXEC, 0)) 3832 priv_granted |= VEXEC; 3833 } 3834 3835 if ((accmode & VREAD) && ((dac_granted & VREAD) == 0) && 3836 !priv_check_cred(cred, PRIV_VFS_READ, 0)) 3837 priv_granted |= VREAD; 3838 3839 if ((accmode & VWRITE) && ((dac_granted & VWRITE) == 0) && 3840 !priv_check_cred(cred, PRIV_VFS_WRITE, 0)) 3841 priv_granted |= (VWRITE | VAPPEND); 3842 3843 if ((accmode & VADMIN) && ((dac_granted & VADMIN) == 0) && 3844 !priv_check_cred(cred, PRIV_VFS_ADMIN, 0)) 3845 priv_granted |= VADMIN; 3846 3847 if ((accmode & (priv_granted | dac_granted)) == accmode) { 3848 /* XXX audit: privilege used */ 3849 if (privused != NULL) 3850 *privused = 1; 3851 return (0); 3852 } 3853 3854 return ((accmode & VADMIN) ? EPERM : EACCES); 3855 } 3856 3857 /* 3858 * Credential check based on process requesting service, and per-attribute 3859 * permissions. 3860 */ 3861 int 3862 extattr_check_cred(struct vnode *vp, int attrnamespace, struct ucred *cred, 3863 struct thread *td, accmode_t accmode) 3864 { 3865 3866 /* 3867 * Kernel-invoked always succeeds. 3868 */ 3869 if (cred == NOCRED) 3870 return (0); 3871 3872 /* 3873 * Do not allow privileged processes in jail to directly manipulate 3874 * system attributes. 3875 */ 3876 switch (attrnamespace) { 3877 case EXTATTR_NAMESPACE_SYSTEM: 3878 /* Potentially should be: return (EPERM); */ 3879 return (priv_check_cred(cred, PRIV_VFS_EXTATTR_SYSTEM, 0)); 3880 case EXTATTR_NAMESPACE_USER: 3881 return (VOP_ACCESS(vp, accmode, cred, td)); 3882 default: 3883 return (EPERM); 3884 } 3885 } 3886 3887 #ifdef DEBUG_VFS_LOCKS 3888 /* 3889 * This only exists to supress warnings from unlocked specfs accesses. It is 3890 * no longer ok to have an unlocked VFS. 3891 */ 3892 #define IGNORE_LOCK(vp) (panicstr != NULL || (vp) == NULL || \ 3893 (vp)->v_type == VCHR || (vp)->v_type == VBAD) 3894 3895 int vfs_badlock_ddb = 1; /* Drop into debugger on violation. */ 3896 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_ddb, CTLFLAG_RW, &vfs_badlock_ddb, 0, 3897 "Drop into debugger on lock violation"); 3898 3899 int vfs_badlock_mutex = 1; /* Check for interlock across VOPs. */ 3900 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_mutex, CTLFLAG_RW, &vfs_badlock_mutex, 3901 0, "Check for interlock across VOPs"); 3902 3903 int vfs_badlock_print = 1; /* Print lock violations. */ 3904 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_print, CTLFLAG_RW, &vfs_badlock_print, 3905 0, "Print lock violations"); 3906 3907 #ifdef KDB 3908 int vfs_badlock_backtrace = 1; /* Print backtrace at lock violations. */ 3909 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_backtrace, CTLFLAG_RW, 3910 &vfs_badlock_backtrace, 0, "Print backtrace at lock violations"); 3911 #endif 3912 3913 static void 3914 vfs_badlock(const char *msg, const char *str, struct vnode *vp) 3915 { 3916 3917 #ifdef KDB 3918 if (vfs_badlock_backtrace) 3919 kdb_backtrace(); 3920 #endif 3921 if (vfs_badlock_print) 3922 printf("%s: %p %s\n", str, (void *)vp, msg); 3923 if (vfs_badlock_ddb) 3924 kdb_enter(KDB_WHY_VFSLOCK, "lock violation"); 3925 } 3926 3927 void 3928 assert_vi_locked(struct vnode *vp, const char *str) 3929 { 3930 3931 if (vfs_badlock_mutex && !mtx_owned(VI_MTX(vp))) 3932 vfs_badlock("interlock is not locked but should be", str, vp); 3933 } 3934 3935 void 3936 assert_vi_unlocked(struct vnode *vp, const char *str) 3937 { 3938 3939 if (vfs_badlock_mutex && mtx_owned(VI_MTX(vp))) 3940 vfs_badlock("interlock is locked but should not be", str, vp); 3941 } 3942 3943 void 3944 assert_vop_locked(struct vnode *vp, const char *str) 3945 { 3946 int locked; 3947 3948 if (!IGNORE_LOCK(vp)) { 3949 locked = VOP_ISLOCKED(vp); 3950 if (locked == 0 || locked == LK_EXCLOTHER) 3951 vfs_badlock("is not locked but should be", str, vp); 3952 } 3953 } 3954 3955 void 3956 assert_vop_unlocked(struct vnode *vp, const char *str) 3957 { 3958 3959 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) == LK_EXCLUSIVE) 3960 vfs_badlock("is locked but should not be", str, vp); 3961 } 3962 3963 void 3964 assert_vop_elocked(struct vnode *vp, const char *str) 3965 { 3966 3967 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) != LK_EXCLUSIVE) 3968 vfs_badlock("is not exclusive locked but should be", str, vp); 3969 } 3970 3971 #if 0 3972 void 3973 assert_vop_elocked_other(struct vnode *vp, const char *str) 3974 { 3975 3976 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) != LK_EXCLOTHER) 3977 vfs_badlock("is not exclusive locked by another thread", 3978 str, vp); 3979 } 3980 3981 void 3982 assert_vop_slocked(struct vnode *vp, const char *str) 3983 { 3984 3985 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) != LK_SHARED) 3986 vfs_badlock("is not locked shared but should be", str, vp); 3987 } 3988 #endif /* 0 */ 3989 #endif /* DEBUG_VFS_LOCKS */ 3990 3991 void 3992 vop_rename_fail(struct vop_rename_args *ap) 3993 { 3994 3995 if (ap->a_tvp != NULL) 3996 vput(ap->a_tvp); 3997 if (ap->a_tdvp == ap->a_tvp) 3998 vrele(ap->a_tdvp); 3999 else 4000 vput(ap->a_tdvp); 4001 vrele(ap->a_fdvp); 4002 vrele(ap->a_fvp); 4003 } 4004 4005 void 4006 vop_rename_pre(void *ap) 4007 { 4008 struct vop_rename_args *a = ap; 4009 4010 #ifdef DEBUG_VFS_LOCKS 4011 if (a->a_tvp) 4012 ASSERT_VI_UNLOCKED(a->a_tvp, "VOP_RENAME"); 4013 ASSERT_VI_UNLOCKED(a->a_tdvp, "VOP_RENAME"); 4014 ASSERT_VI_UNLOCKED(a->a_fvp, "VOP_RENAME"); 4015 ASSERT_VI_UNLOCKED(a->a_fdvp, "VOP_RENAME"); 4016 4017 /* Check the source (from). */ 4018 if (a->a_tdvp->v_vnlock != a->a_fdvp->v_vnlock && 4019 (a->a_tvp == NULL || a->a_tvp->v_vnlock != a->a_fdvp->v_vnlock)) 4020 ASSERT_VOP_UNLOCKED(a->a_fdvp, "vop_rename: fdvp locked"); 4021 if (a->a_tvp == NULL || a->a_tvp->v_vnlock != a->a_fvp->v_vnlock) 4022 ASSERT_VOP_UNLOCKED(a->a_fvp, "vop_rename: fvp locked"); 4023 4024 /* Check the target. */ 4025 if (a->a_tvp) 4026 ASSERT_VOP_LOCKED(a->a_tvp, "vop_rename: tvp not locked"); 4027 ASSERT_VOP_LOCKED(a->a_tdvp, "vop_rename: tdvp not locked"); 4028 #endif 4029 if (a->a_tdvp != a->a_fdvp) 4030 vhold(a->a_fdvp); 4031 if (a->a_tvp != a->a_fvp) 4032 vhold(a->a_fvp); 4033 vhold(a->a_tdvp); 4034 if (a->a_tvp) 4035 vhold(a->a_tvp); 4036 } 4037 4038 void 4039 vop_strategy_pre(void *ap) 4040 { 4041 #ifdef DEBUG_VFS_LOCKS 4042 struct vop_strategy_args *a; 4043 struct buf *bp; 4044 4045 a = ap; 4046 bp = a->a_bp; 4047 4048 /* 4049 * Cluster ops lock their component buffers but not the IO container. 4050 */ 4051 if ((bp->b_flags & B_CLUSTER) != 0) 4052 return; 4053 4054 if (panicstr == NULL && !BUF_ISLOCKED(bp)) { 4055 if (vfs_badlock_print) 4056 printf( 4057 "VOP_STRATEGY: bp is not locked but should be\n"); 4058 if (vfs_badlock_ddb) 4059 kdb_enter(KDB_WHY_VFSLOCK, "lock violation"); 4060 } 4061 #endif 4062 } 4063 4064 void 4065 vop_lock_pre(void *ap) 4066 { 4067 #ifdef DEBUG_VFS_LOCKS 4068 struct vop_lock1_args *a = ap; 4069 4070 if ((a->a_flags & LK_INTERLOCK) == 0) 4071 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_LOCK"); 4072 else 4073 ASSERT_VI_LOCKED(a->a_vp, "VOP_LOCK"); 4074 #endif 4075 } 4076 4077 void 4078 vop_lock_post(void *ap, int rc) 4079 { 4080 #ifdef DEBUG_VFS_LOCKS 4081 struct vop_lock1_args *a = ap; 4082 4083 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_LOCK"); 4084 if (rc == 0 && (a->a_flags & LK_EXCLOTHER) == 0) 4085 ASSERT_VOP_LOCKED(a->a_vp, "VOP_LOCK"); 4086 #endif 4087 } 4088 4089 void 4090 vop_unlock_pre(void *ap) 4091 { 4092 #ifdef DEBUG_VFS_LOCKS 4093 struct vop_unlock_args *a = ap; 4094 4095 if (a->a_flags & LK_INTERLOCK) 4096 ASSERT_VI_LOCKED(a->a_vp, "VOP_UNLOCK"); 4097 ASSERT_VOP_LOCKED(a->a_vp, "VOP_UNLOCK"); 4098 #endif 4099 } 4100 4101 void 4102 vop_unlock_post(void *ap, int rc) 4103 { 4104 #ifdef DEBUG_VFS_LOCKS 4105 struct vop_unlock_args *a = ap; 4106 4107 if (a->a_flags & LK_INTERLOCK) 4108 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_UNLOCK"); 4109 #endif 4110 } 4111 4112 void 4113 vop_create_post(void *ap, int rc) 4114 { 4115 struct vop_create_args *a = ap; 4116 4117 if (!rc) 4118 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 4119 } 4120 4121 void 4122 vop_deleteextattr_post(void *ap, int rc) 4123 { 4124 struct vop_deleteextattr_args *a = ap; 4125 4126 if (!rc) 4127 VFS_KNOTE_LOCKED(a->a_vp, NOTE_ATTRIB); 4128 } 4129 4130 void 4131 vop_link_post(void *ap, int rc) 4132 { 4133 struct vop_link_args *a = ap; 4134 4135 if (!rc) { 4136 VFS_KNOTE_LOCKED(a->a_vp, NOTE_LINK); 4137 VFS_KNOTE_LOCKED(a->a_tdvp, NOTE_WRITE); 4138 } 4139 } 4140 4141 void 4142 vop_mkdir_post(void *ap, int rc) 4143 { 4144 struct vop_mkdir_args *a = ap; 4145 4146 if (!rc) 4147 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE | NOTE_LINK); 4148 } 4149 4150 void 4151 vop_mknod_post(void *ap, int rc) 4152 { 4153 struct vop_mknod_args *a = ap; 4154 4155 if (!rc) 4156 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 4157 } 4158 4159 void 4160 vop_remove_post(void *ap, int rc) 4161 { 4162 struct vop_remove_args *a = ap; 4163 4164 if (!rc) { 4165 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 4166 VFS_KNOTE_LOCKED(a->a_vp, NOTE_DELETE); 4167 } 4168 } 4169 4170 void 4171 vop_rename_post(void *ap, int rc) 4172 { 4173 struct vop_rename_args *a = ap; 4174 4175 if (!rc) { 4176 VFS_KNOTE_UNLOCKED(a->a_fdvp, NOTE_WRITE); 4177 VFS_KNOTE_UNLOCKED(a->a_tdvp, NOTE_WRITE); 4178 VFS_KNOTE_UNLOCKED(a->a_fvp, NOTE_RENAME); 4179 if (a->a_tvp) 4180 VFS_KNOTE_UNLOCKED(a->a_tvp, NOTE_DELETE); 4181 } 4182 if (a->a_tdvp != a->a_fdvp) 4183 vdrop(a->a_fdvp); 4184 if (a->a_tvp != a->a_fvp) 4185 vdrop(a->a_fvp); 4186 vdrop(a->a_tdvp); 4187 if (a->a_tvp) 4188 vdrop(a->a_tvp); 4189 } 4190 4191 void 4192 vop_rmdir_post(void *ap, int rc) 4193 { 4194 struct vop_rmdir_args *a = ap; 4195 4196 if (!rc) { 4197 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE | NOTE_LINK); 4198 VFS_KNOTE_LOCKED(a->a_vp, NOTE_DELETE); 4199 } 4200 } 4201 4202 void 4203 vop_setattr_post(void *ap, int rc) 4204 { 4205 struct vop_setattr_args *a = ap; 4206 4207 if (!rc) 4208 VFS_KNOTE_LOCKED(a->a_vp, NOTE_ATTRIB); 4209 } 4210 4211 void 4212 vop_setextattr_post(void *ap, int rc) 4213 { 4214 struct vop_setextattr_args *a = ap; 4215 4216 if (!rc) 4217 VFS_KNOTE_LOCKED(a->a_vp, NOTE_ATTRIB); 4218 } 4219 4220 void 4221 vop_symlink_post(void *ap, int rc) 4222 { 4223 struct vop_symlink_args *a = ap; 4224 4225 if (!rc) 4226 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 4227 } 4228 4229 static struct knlist fs_knlist; 4230 4231 static void 4232 vfs_event_init(void *arg) 4233 { 4234 knlist_init_mtx(&fs_knlist, NULL); 4235 } 4236 /* XXX - correct order? */ 4237 SYSINIT(vfs_knlist, SI_SUB_VFS, SI_ORDER_ANY, vfs_event_init, NULL); 4238 4239 void 4240 vfs_event_signal(fsid_t *fsid, uint32_t event, intptr_t data __unused) 4241 { 4242 4243 KNOTE_UNLOCKED(&fs_knlist, event); 4244 } 4245 4246 static int filt_fsattach(struct knote *kn); 4247 static void filt_fsdetach(struct knote *kn); 4248 static int filt_fsevent(struct knote *kn, long hint); 4249 4250 struct filterops fs_filtops = { 4251 .f_isfd = 0, 4252 .f_attach = filt_fsattach, 4253 .f_detach = filt_fsdetach, 4254 .f_event = filt_fsevent 4255 }; 4256 4257 static int 4258 filt_fsattach(struct knote *kn) 4259 { 4260 4261 kn->kn_flags |= EV_CLEAR; 4262 knlist_add(&fs_knlist, kn, 0); 4263 return (0); 4264 } 4265 4266 static void 4267 filt_fsdetach(struct knote *kn) 4268 { 4269 4270 knlist_remove(&fs_knlist, kn, 0); 4271 } 4272 4273 static int 4274 filt_fsevent(struct knote *kn, long hint) 4275 { 4276 4277 kn->kn_fflags |= hint; 4278 return (kn->kn_fflags != 0); 4279 } 4280 4281 static int 4282 sysctl_vfs_ctl(SYSCTL_HANDLER_ARGS) 4283 { 4284 struct vfsidctl vc; 4285 int error; 4286 struct mount *mp; 4287 4288 error = SYSCTL_IN(req, &vc, sizeof(vc)); 4289 if (error) 4290 return (error); 4291 if (vc.vc_vers != VFS_CTL_VERS1) 4292 return (EINVAL); 4293 mp = vfs_getvfs(&vc.vc_fsid); 4294 if (mp == NULL) 4295 return (ENOENT); 4296 /* ensure that a specific sysctl goes to the right filesystem. */ 4297 if (strcmp(vc.vc_fstypename, "*") != 0 && 4298 strcmp(vc.vc_fstypename, mp->mnt_vfc->vfc_name) != 0) { 4299 vfs_rel(mp); 4300 return (EINVAL); 4301 } 4302 VCTLTOREQ(&vc, req); 4303 error = VFS_SYSCTL(mp, vc.vc_op, req); 4304 vfs_rel(mp); 4305 return (error); 4306 } 4307 4308 SYSCTL_PROC(_vfs, OID_AUTO, ctl, CTLTYPE_OPAQUE | CTLFLAG_WR, 4309 NULL, 0, sysctl_vfs_ctl, "", 4310 "Sysctl by fsid"); 4311 4312 /* 4313 * Function to initialize a va_filerev field sensibly. 4314 * XXX: Wouldn't a random number make a lot more sense ?? 4315 */ 4316 u_quad_t 4317 init_va_filerev(void) 4318 { 4319 struct bintime bt; 4320 4321 getbinuptime(&bt); 4322 return (((u_quad_t)bt.sec << 32LL) | (bt.frac >> 32LL)); 4323 } 4324 4325 static int filt_vfsread(struct knote *kn, long hint); 4326 static int filt_vfswrite(struct knote *kn, long hint); 4327 static int filt_vfsvnode(struct knote *kn, long hint); 4328 static void filt_vfsdetach(struct knote *kn); 4329 static struct filterops vfsread_filtops = { 4330 .f_isfd = 1, 4331 .f_detach = filt_vfsdetach, 4332 .f_event = filt_vfsread 4333 }; 4334 static struct filterops vfswrite_filtops = { 4335 .f_isfd = 1, 4336 .f_detach = filt_vfsdetach, 4337 .f_event = filt_vfswrite 4338 }; 4339 static struct filterops vfsvnode_filtops = { 4340 .f_isfd = 1, 4341 .f_detach = filt_vfsdetach, 4342 .f_event = filt_vfsvnode 4343 }; 4344 4345 static void 4346 vfs_knllock(void *arg) 4347 { 4348 struct vnode *vp = arg; 4349 4350 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 4351 } 4352 4353 static void 4354 vfs_knlunlock(void *arg) 4355 { 4356 struct vnode *vp = arg; 4357 4358 VOP_UNLOCK(vp, 0); 4359 } 4360 4361 static void 4362 vfs_knl_assert_locked(void *arg) 4363 { 4364 #ifdef DEBUG_VFS_LOCKS 4365 struct vnode *vp = arg; 4366 4367 ASSERT_VOP_LOCKED(vp, "vfs_knl_assert_locked"); 4368 #endif 4369 } 4370 4371 static void 4372 vfs_knl_assert_unlocked(void *arg) 4373 { 4374 #ifdef DEBUG_VFS_LOCKS 4375 struct vnode *vp = arg; 4376 4377 ASSERT_VOP_UNLOCKED(vp, "vfs_knl_assert_unlocked"); 4378 #endif 4379 } 4380 4381 int 4382 vfs_kqfilter(struct vop_kqfilter_args *ap) 4383 { 4384 struct vnode *vp = ap->a_vp; 4385 struct knote *kn = ap->a_kn; 4386 struct knlist *knl; 4387 4388 switch (kn->kn_filter) { 4389 case EVFILT_READ: 4390 kn->kn_fop = &vfsread_filtops; 4391 break; 4392 case EVFILT_WRITE: 4393 kn->kn_fop = &vfswrite_filtops; 4394 break; 4395 case EVFILT_VNODE: 4396 kn->kn_fop = &vfsvnode_filtops; 4397 break; 4398 default: 4399 return (EINVAL); 4400 } 4401 4402 kn->kn_hook = (caddr_t)vp; 4403 4404 v_addpollinfo(vp); 4405 if (vp->v_pollinfo == NULL) 4406 return (ENOMEM); 4407 knl = &vp->v_pollinfo->vpi_selinfo.si_note; 4408 vhold(vp); 4409 knlist_add(knl, kn, 0); 4410 4411 return (0); 4412 } 4413 4414 /* 4415 * Detach knote from vnode 4416 */ 4417 static void 4418 filt_vfsdetach(struct knote *kn) 4419 { 4420 struct vnode *vp = (struct vnode *)kn->kn_hook; 4421 4422 KASSERT(vp->v_pollinfo != NULL, ("Missing v_pollinfo")); 4423 knlist_remove(&vp->v_pollinfo->vpi_selinfo.si_note, kn, 0); 4424 vdrop(vp); 4425 } 4426 4427 /*ARGSUSED*/ 4428 static int 4429 filt_vfsread(struct knote *kn, long hint) 4430 { 4431 struct vnode *vp = (struct vnode *)kn->kn_hook; 4432 struct vattr va; 4433 int res; 4434 4435 /* 4436 * filesystem is gone, so set the EOF flag and schedule 4437 * the knote for deletion. 4438 */ 4439 if (hint == NOTE_REVOKE) { 4440 VI_LOCK(vp); 4441 kn->kn_flags |= (EV_EOF | EV_ONESHOT); 4442 VI_UNLOCK(vp); 4443 return (1); 4444 } 4445 4446 if (VOP_GETATTR(vp, &va, curthread->td_ucred)) 4447 return (0); 4448 4449 VI_LOCK(vp); 4450 kn->kn_data = va.va_size - kn->kn_fp->f_offset; 4451 res = (kn->kn_data != 0); 4452 VI_UNLOCK(vp); 4453 return (res); 4454 } 4455 4456 /*ARGSUSED*/ 4457 static int 4458 filt_vfswrite(struct knote *kn, long hint) 4459 { 4460 struct vnode *vp = (struct vnode *)kn->kn_hook; 4461 4462 VI_LOCK(vp); 4463 4464 /* 4465 * filesystem is gone, so set the EOF flag and schedule 4466 * the knote for deletion. 4467 */ 4468 if (hint == NOTE_REVOKE) 4469 kn->kn_flags |= (EV_EOF | EV_ONESHOT); 4470 4471 kn->kn_data = 0; 4472 VI_UNLOCK(vp); 4473 return (1); 4474 } 4475 4476 static int 4477 filt_vfsvnode(struct knote *kn, long hint) 4478 { 4479 struct vnode *vp = (struct vnode *)kn->kn_hook; 4480 int res; 4481 4482 VI_LOCK(vp); 4483 if (kn->kn_sfflags & hint) 4484 kn->kn_fflags |= hint; 4485 if (hint == NOTE_REVOKE) { 4486 kn->kn_flags |= EV_EOF; 4487 VI_UNLOCK(vp); 4488 return (1); 4489 } 4490 res = (kn->kn_fflags != 0); 4491 VI_UNLOCK(vp); 4492 return (res); 4493 } 4494 4495 int 4496 vfs_read_dirent(struct vop_readdir_args *ap, struct dirent *dp, off_t off) 4497 { 4498 int error; 4499 4500 if (dp->d_reclen > ap->a_uio->uio_resid) 4501 return (ENAMETOOLONG); 4502 error = uiomove(dp, dp->d_reclen, ap->a_uio); 4503 if (error) { 4504 if (ap->a_ncookies != NULL) { 4505 if (ap->a_cookies != NULL) 4506 free(ap->a_cookies, M_TEMP); 4507 ap->a_cookies = NULL; 4508 *ap->a_ncookies = 0; 4509 } 4510 return (error); 4511 } 4512 if (ap->a_ncookies == NULL) 4513 return (0); 4514 4515 KASSERT(ap->a_cookies, 4516 ("NULL ap->a_cookies value with non-NULL ap->a_ncookies!")); 4517 4518 *ap->a_cookies = realloc(*ap->a_cookies, 4519 (*ap->a_ncookies + 1) * sizeof(u_long), M_TEMP, M_WAITOK | M_ZERO); 4520 (*ap->a_cookies)[*ap->a_ncookies] = off; 4521 return (0); 4522 } 4523 4524 /* 4525 * Mark for update the access time of the file if the filesystem 4526 * supports VOP_MARKATIME. This functionality is used by execve and 4527 * mmap, so we want to avoid the I/O implied by directly setting 4528 * va_atime for the sake of efficiency. 4529 */ 4530 void 4531 vfs_mark_atime(struct vnode *vp, struct ucred *cred) 4532 { 4533 struct mount *mp; 4534 4535 mp = vp->v_mount; 4536 ASSERT_VOP_LOCKED(vp, "vfs_mark_atime"); 4537 if (mp != NULL && (mp->mnt_flag & (MNT_NOATIME | MNT_RDONLY)) == 0) 4538 (void)VOP_MARKATIME(vp); 4539 } 4540 4541 /* 4542 * The purpose of this routine is to remove granularity from accmode_t, 4543 * reducing it into standard unix access bits - VEXEC, VREAD, VWRITE, 4544 * VADMIN and VAPPEND. 4545 * 4546 * If it returns 0, the caller is supposed to continue with the usual 4547 * access checks using 'accmode' as modified by this routine. If it 4548 * returns nonzero value, the caller is supposed to return that value 4549 * as errno. 4550 * 4551 * Note that after this routine runs, accmode may be zero. 4552 */ 4553 int 4554 vfs_unixify_accmode(accmode_t *accmode) 4555 { 4556 /* 4557 * There is no way to specify explicit "deny" rule using 4558 * file mode or POSIX.1e ACLs. 4559 */ 4560 if (*accmode & VEXPLICIT_DENY) { 4561 *accmode = 0; 4562 return (0); 4563 } 4564 4565 /* 4566 * None of these can be translated into usual access bits. 4567 * Also, the common case for NFSv4 ACLs is to not contain 4568 * either of these bits. Caller should check for VWRITE 4569 * on the containing directory instead. 4570 */ 4571 if (*accmode & (VDELETE_CHILD | VDELETE)) 4572 return (EPERM); 4573 4574 if (*accmode & VADMIN_PERMS) { 4575 *accmode &= ~VADMIN_PERMS; 4576 *accmode |= VADMIN; 4577 } 4578 4579 /* 4580 * There is no way to deny VREAD_ATTRIBUTES, VREAD_ACL 4581 * or VSYNCHRONIZE using file mode or POSIX.1e ACL. 4582 */ 4583 *accmode &= ~(VSTAT_PERMS | VSYNCHRONIZE); 4584 4585 return (0); 4586 } 4587 4588 /* 4589 * These are helper functions for filesystems to traverse all 4590 * their vnodes. See MNT_VNODE_FOREACH_ALL() in sys/mount.h. 4591 * 4592 * This interface replaces MNT_VNODE_FOREACH. 4593 */ 4594 4595 MALLOC_DEFINE(M_VNODE_MARKER, "vnodemarker", "vnode marker"); 4596 4597 struct vnode * 4598 __mnt_vnode_next_all(struct vnode **mvp, struct mount *mp) 4599 { 4600 struct vnode *vp; 4601 4602 if (should_yield()) 4603 kern_yield(PRI_USER); 4604 MNT_ILOCK(mp); 4605 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch")); 4606 vp = TAILQ_NEXT(*mvp, v_nmntvnodes); 4607 while (vp != NULL && (vp->v_type == VMARKER || 4608 (vp->v_iflag & VI_DOOMED) != 0)) 4609 vp = TAILQ_NEXT(vp, v_nmntvnodes); 4610 4611 /* Check if we are done */ 4612 if (vp == NULL) { 4613 __mnt_vnode_markerfree_all(mvp, mp); 4614 /* MNT_IUNLOCK(mp); -- done in above function */ 4615 mtx_assert(MNT_MTX(mp), MA_NOTOWNED); 4616 return (NULL); 4617 } 4618 TAILQ_REMOVE(&mp->mnt_nvnodelist, *mvp, v_nmntvnodes); 4619 TAILQ_INSERT_AFTER(&mp->mnt_nvnodelist, vp, *mvp, v_nmntvnodes); 4620 VI_LOCK(vp); 4621 MNT_IUNLOCK(mp); 4622 return (vp); 4623 } 4624 4625 struct vnode * 4626 __mnt_vnode_first_all(struct vnode **mvp, struct mount *mp) 4627 { 4628 struct vnode *vp; 4629 4630 *mvp = malloc(sizeof(struct vnode), M_VNODE_MARKER, M_WAITOK | M_ZERO); 4631 MNT_ILOCK(mp); 4632 MNT_REF(mp); 4633 (*mvp)->v_type = VMARKER; 4634 4635 vp = TAILQ_FIRST(&mp->mnt_nvnodelist); 4636 while (vp != NULL && (vp->v_type == VMARKER || 4637 (vp->v_iflag & VI_DOOMED) != 0)) 4638 vp = TAILQ_NEXT(vp, v_nmntvnodes); 4639 4640 /* Check if we are done */ 4641 if (vp == NULL) { 4642 MNT_REL(mp); 4643 MNT_IUNLOCK(mp); 4644 free(*mvp, M_VNODE_MARKER); 4645 *mvp = NULL; 4646 return (NULL); 4647 } 4648 (*mvp)->v_mount = mp; 4649 TAILQ_INSERT_AFTER(&mp->mnt_nvnodelist, vp, *mvp, v_nmntvnodes); 4650 VI_LOCK(vp); 4651 MNT_IUNLOCK(mp); 4652 return (vp); 4653 } 4654 4655 4656 void 4657 __mnt_vnode_markerfree_all(struct vnode **mvp, struct mount *mp) 4658 { 4659 4660 if (*mvp == NULL) { 4661 MNT_IUNLOCK(mp); 4662 return; 4663 } 4664 4665 mtx_assert(MNT_MTX(mp), MA_OWNED); 4666 4667 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch")); 4668 TAILQ_REMOVE(&mp->mnt_nvnodelist, *mvp, v_nmntvnodes); 4669 MNT_REL(mp); 4670 MNT_IUNLOCK(mp); 4671 free(*mvp, M_VNODE_MARKER); 4672 *mvp = NULL; 4673 } 4674 4675 /* 4676 * These are helper functions for filesystems to traverse their 4677 * active vnodes. See MNT_VNODE_FOREACH_ACTIVE() in sys/mount.h 4678 */ 4679 static void 4680 mnt_vnode_markerfree_active(struct vnode **mvp, struct mount *mp) 4681 { 4682 4683 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch")); 4684 4685 MNT_ILOCK(mp); 4686 MNT_REL(mp); 4687 MNT_IUNLOCK(mp); 4688 free(*mvp, M_VNODE_MARKER); 4689 *mvp = NULL; 4690 } 4691 4692 static struct vnode * 4693 mnt_vnode_next_active(struct vnode **mvp, struct mount *mp) 4694 { 4695 struct vnode *vp, *nvp; 4696 4697 mtx_assert(&vnode_free_list_mtx, MA_OWNED); 4698 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch")); 4699 restart: 4700 vp = TAILQ_NEXT(*mvp, v_actfreelist); 4701 TAILQ_REMOVE(&mp->mnt_activevnodelist, *mvp, v_actfreelist); 4702 while (vp != NULL) { 4703 if (vp->v_type == VMARKER) { 4704 vp = TAILQ_NEXT(vp, v_actfreelist); 4705 continue; 4706 } 4707 if (!VI_TRYLOCK(vp)) { 4708 if (mp_ncpus == 1 || should_yield()) { 4709 TAILQ_INSERT_BEFORE(vp, *mvp, v_actfreelist); 4710 mtx_unlock(&vnode_free_list_mtx); 4711 pause("vnacti", 1); 4712 mtx_lock(&vnode_free_list_mtx); 4713 goto restart; 4714 } 4715 continue; 4716 } 4717 KASSERT(vp->v_type != VMARKER, ("locked marker %p", vp)); 4718 KASSERT(vp->v_mount == mp || vp->v_mount == NULL, 4719 ("alien vnode on the active list %p %p", vp, mp)); 4720 if (vp->v_mount == mp && (vp->v_iflag & VI_DOOMED) == 0) 4721 break; 4722 nvp = TAILQ_NEXT(vp, v_actfreelist); 4723 VI_UNLOCK(vp); 4724 vp = nvp; 4725 } 4726 4727 /* Check if we are done */ 4728 if (vp == NULL) { 4729 mtx_unlock(&vnode_free_list_mtx); 4730 mnt_vnode_markerfree_active(mvp, mp); 4731 return (NULL); 4732 } 4733 TAILQ_INSERT_AFTER(&mp->mnt_activevnodelist, vp, *mvp, v_actfreelist); 4734 mtx_unlock(&vnode_free_list_mtx); 4735 ASSERT_VI_LOCKED(vp, "active iter"); 4736 KASSERT((vp->v_iflag & VI_ACTIVE) != 0, ("Non-active vp %p", vp)); 4737 return (vp); 4738 } 4739 4740 struct vnode * 4741 __mnt_vnode_next_active(struct vnode **mvp, struct mount *mp) 4742 { 4743 4744 if (should_yield()) 4745 kern_yield(PRI_USER); 4746 mtx_lock(&vnode_free_list_mtx); 4747 return (mnt_vnode_next_active(mvp, mp)); 4748 } 4749 4750 struct vnode * 4751 __mnt_vnode_first_active(struct vnode **mvp, struct mount *mp) 4752 { 4753 struct vnode *vp; 4754 4755 *mvp = malloc(sizeof(struct vnode), M_VNODE_MARKER, M_WAITOK | M_ZERO); 4756 MNT_ILOCK(mp); 4757 MNT_REF(mp); 4758 MNT_IUNLOCK(mp); 4759 (*mvp)->v_type = VMARKER; 4760 (*mvp)->v_mount = mp; 4761 4762 mtx_lock(&vnode_free_list_mtx); 4763 vp = TAILQ_FIRST(&mp->mnt_activevnodelist); 4764 if (vp == NULL) { 4765 mtx_unlock(&vnode_free_list_mtx); 4766 mnt_vnode_markerfree_active(mvp, mp); 4767 return (NULL); 4768 } 4769 TAILQ_INSERT_BEFORE(vp, *mvp, v_actfreelist); 4770 return (mnt_vnode_next_active(mvp, mp)); 4771 } 4772 4773 void 4774 __mnt_vnode_markerfree_active(struct vnode **mvp, struct mount *mp) 4775 { 4776 4777 if (*mvp == NULL) 4778 return; 4779 4780 mtx_lock(&vnode_free_list_mtx); 4781 TAILQ_REMOVE(&mp->mnt_activevnodelist, *mvp, v_actfreelist); 4782 mtx_unlock(&vnode_free_list_mtx); 4783 mnt_vnode_markerfree_active(mvp, mp); 4784 } 4785