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