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 + cnt.v_page_count / 16 + 3 * min(98304 * 4, 334 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 = cnt.v_page_count * 2 / usevnodes; 712 done = 0; 713 vn_start_write(NULL, &mp, V_WAIT); 714 MNT_ILOCK(mp); 715 count = mp->mnt_nvnodelistsize / 10 + 1; 716 while (count != 0) { 717 vp = TAILQ_FIRST(&mp->mnt_nvnodelist); 718 while (vp != NULL && vp->v_type == VMARKER) 719 vp = TAILQ_NEXT(vp, v_nmntvnodes); 720 if (vp == NULL) 721 break; 722 TAILQ_REMOVE(&mp->mnt_nvnodelist, vp, v_nmntvnodes); 723 TAILQ_INSERT_TAIL(&mp->mnt_nvnodelist, vp, v_nmntvnodes); 724 --count; 725 if (!VI_TRYLOCK(vp)) 726 goto next_iter; 727 /* 728 * If it's been deconstructed already, it's still 729 * referenced, or it exceeds the trigger, skip it. 730 */ 731 if (vp->v_usecount || 732 (!vlru_allow_cache_src && 733 !LIST_EMPTY(&(vp)->v_cache_src)) || 734 (vp->v_iflag & VI_DOOMED) != 0 || (vp->v_object != NULL && 735 vp->v_object->resident_page_count > trigger)) { 736 VI_UNLOCK(vp); 737 goto next_iter; 738 } 739 MNT_IUNLOCK(mp); 740 vholdl(vp); 741 if (VOP_LOCK(vp, LK_INTERLOCK|LK_EXCLUSIVE|LK_NOWAIT)) { 742 vdrop(vp); 743 goto next_iter_mntunlocked; 744 } 745 VI_LOCK(vp); 746 /* 747 * v_usecount may have been bumped after VOP_LOCK() dropped 748 * the vnode interlock and before it was locked again. 749 * 750 * It is not necessary to recheck VI_DOOMED because it can 751 * only be set by another thread that holds both the vnode 752 * lock and vnode interlock. If another thread has the 753 * vnode lock before we get to VOP_LOCK() and obtains the 754 * vnode interlock after VOP_LOCK() drops the vnode 755 * interlock, the other thread will be unable to drop the 756 * vnode lock before our VOP_LOCK() call fails. 757 */ 758 if (vp->v_usecount || 759 (!vlru_allow_cache_src && 760 !LIST_EMPTY(&(vp)->v_cache_src)) || 761 (vp->v_object != NULL && 762 vp->v_object->resident_page_count > trigger)) { 763 VOP_UNLOCK(vp, LK_INTERLOCK); 764 vdrop(vp); 765 goto next_iter_mntunlocked; 766 } 767 KASSERT((vp->v_iflag & VI_DOOMED) == 0, 768 ("VI_DOOMED unexpectedly detected in vlrureclaim()")); 769 vgonel(vp); 770 VOP_UNLOCK(vp, 0); 771 vdropl(vp); 772 done++; 773 next_iter_mntunlocked: 774 if (!should_yield()) 775 goto relock_mnt; 776 goto yield; 777 next_iter: 778 if (!should_yield()) 779 continue; 780 MNT_IUNLOCK(mp); 781 yield: 782 kern_yield(PRI_USER); 783 relock_mnt: 784 MNT_ILOCK(mp); 785 } 786 MNT_IUNLOCK(mp); 787 vn_finished_write(mp); 788 return done; 789 } 790 791 /* 792 * Attempt to keep the free list at wantfreevnodes length. 793 */ 794 static void 795 vnlru_free(int count) 796 { 797 struct vnode *vp; 798 799 mtx_assert(&vnode_free_list_mtx, MA_OWNED); 800 for (; count > 0; count--) { 801 vp = TAILQ_FIRST(&vnode_free_list); 802 /* 803 * The list can be modified while the free_list_mtx 804 * has been dropped and vp could be NULL here. 805 */ 806 if (!vp) 807 break; 808 VNASSERT(vp->v_op != NULL, vp, 809 ("vnlru_free: vnode already reclaimed.")); 810 KASSERT((vp->v_iflag & VI_FREE) != 0, 811 ("Removing vnode not on freelist")); 812 KASSERT((vp->v_iflag & VI_ACTIVE) == 0, 813 ("Mangling active vnode")); 814 TAILQ_REMOVE(&vnode_free_list, vp, v_actfreelist); 815 /* 816 * Don't recycle if we can't get the interlock. 817 */ 818 if (!VI_TRYLOCK(vp)) { 819 TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_actfreelist); 820 continue; 821 } 822 VNASSERT(VCANRECYCLE(vp), vp, 823 ("vp inconsistent on freelist")); 824 freevnodes--; 825 vp->v_iflag &= ~VI_FREE; 826 vholdl(vp); 827 mtx_unlock(&vnode_free_list_mtx); 828 VI_UNLOCK(vp); 829 vtryrecycle(vp); 830 /* 831 * If the recycled succeeded this vdrop will actually free 832 * the vnode. If not it will simply place it back on 833 * the free list. 834 */ 835 vdrop(vp); 836 mtx_lock(&vnode_free_list_mtx); 837 } 838 } 839 /* 840 * Attempt to recycle vnodes in a context that is always safe to block. 841 * Calling vlrurecycle() from the bowels of filesystem code has some 842 * interesting deadlock problems. 843 */ 844 static struct proc *vnlruproc; 845 static int vnlruproc_sig; 846 847 static void 848 vnlru_proc(void) 849 { 850 struct mount *mp, *nmp; 851 int done; 852 struct proc *p = vnlruproc; 853 854 EVENTHANDLER_REGISTER(shutdown_pre_sync, kproc_shutdown, p, 855 SHUTDOWN_PRI_FIRST); 856 857 for (;;) { 858 kproc_suspend_check(p); 859 mtx_lock(&vnode_free_list_mtx); 860 if (freevnodes > wantfreevnodes) 861 vnlru_free(freevnodes - wantfreevnodes); 862 if (numvnodes <= desiredvnodes * 9 / 10) { 863 vnlruproc_sig = 0; 864 wakeup(&vnlruproc_sig); 865 msleep(vnlruproc, &vnode_free_list_mtx, 866 PVFS|PDROP, "vlruwt", hz); 867 continue; 868 } 869 mtx_unlock(&vnode_free_list_mtx); 870 done = 0; 871 mtx_lock(&mountlist_mtx); 872 for (mp = TAILQ_FIRST(&mountlist); mp != NULL; mp = nmp) { 873 if (vfs_busy(mp, MBF_NOWAIT | MBF_MNTLSTLOCK)) { 874 nmp = TAILQ_NEXT(mp, mnt_list); 875 continue; 876 } 877 done += vlrureclaim(mp); 878 mtx_lock(&mountlist_mtx); 879 nmp = TAILQ_NEXT(mp, mnt_list); 880 vfs_unbusy(mp); 881 } 882 mtx_unlock(&mountlist_mtx); 883 if (done == 0) { 884 #if 0 885 /* These messages are temporary debugging aids */ 886 if (vnlru_nowhere < 5) 887 printf("vnlru process getting nowhere..\n"); 888 else if (vnlru_nowhere == 5) 889 printf("vnlru process messages stopped.\n"); 890 #endif 891 vnlru_nowhere++; 892 tsleep(vnlruproc, PPAUSE, "vlrup", hz * 3); 893 } else 894 kern_yield(PRI_USER); 895 } 896 } 897 898 static struct kproc_desc vnlru_kp = { 899 "vnlru", 900 vnlru_proc, 901 &vnlruproc 902 }; 903 SYSINIT(vnlru, SI_SUB_KTHREAD_UPDATE, SI_ORDER_FIRST, kproc_start, 904 &vnlru_kp); 905 906 /* 907 * Routines having to do with the management of the vnode table. 908 */ 909 910 /* 911 * Try to recycle a freed vnode. We abort if anyone picks up a reference 912 * before we actually vgone(). This function must be called with the vnode 913 * held to prevent the vnode from being returned to the free list midway 914 * through vgone(). 915 */ 916 static int 917 vtryrecycle(struct vnode *vp) 918 { 919 struct mount *vnmp; 920 921 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 922 VNASSERT(vp->v_holdcnt, vp, 923 ("vtryrecycle: Recycling vp %p without a reference.", vp)); 924 /* 925 * This vnode may found and locked via some other list, if so we 926 * can't recycle it yet. 927 */ 928 if (VOP_LOCK(vp, LK_EXCLUSIVE | LK_NOWAIT) != 0) { 929 CTR2(KTR_VFS, 930 "%s: impossible to recycle, vp %p lock is already held", 931 __func__, vp); 932 return (EWOULDBLOCK); 933 } 934 /* 935 * Don't recycle if its filesystem is being suspended. 936 */ 937 if (vn_start_write(vp, &vnmp, V_NOWAIT) != 0) { 938 VOP_UNLOCK(vp, 0); 939 CTR2(KTR_VFS, 940 "%s: impossible to recycle, cannot start the write for %p", 941 __func__, vp); 942 return (EBUSY); 943 } 944 /* 945 * If we got this far, we need to acquire the interlock and see if 946 * anyone picked up this vnode from another list. If not, we will 947 * mark it with DOOMED via vgonel() so that anyone who does find it 948 * will skip over it. 949 */ 950 VI_LOCK(vp); 951 if (vp->v_usecount) { 952 VOP_UNLOCK(vp, LK_INTERLOCK); 953 vn_finished_write(vnmp); 954 CTR2(KTR_VFS, 955 "%s: impossible to recycle, %p is already referenced", 956 __func__, vp); 957 return (EBUSY); 958 } 959 if ((vp->v_iflag & VI_DOOMED) == 0) 960 vgonel(vp); 961 VOP_UNLOCK(vp, LK_INTERLOCK); 962 vn_finished_write(vnmp); 963 return (0); 964 } 965 966 /* 967 * Wait for available vnodes. 968 */ 969 static int 970 getnewvnode_wait(int suspended) 971 { 972 973 mtx_assert(&vnode_free_list_mtx, MA_OWNED); 974 if (numvnodes > desiredvnodes) { 975 if (suspended) { 976 /* 977 * File system is beeing suspended, we cannot risk a 978 * deadlock here, so allocate new vnode anyway. 979 */ 980 if (freevnodes > wantfreevnodes) 981 vnlru_free(freevnodes - wantfreevnodes); 982 return (0); 983 } 984 if (vnlruproc_sig == 0) { 985 vnlruproc_sig = 1; /* avoid unnecessary wakeups */ 986 wakeup(vnlruproc); 987 } 988 msleep(&vnlruproc_sig, &vnode_free_list_mtx, PVFS, 989 "vlruwk", hz); 990 } 991 return (numvnodes > desiredvnodes ? ENFILE : 0); 992 } 993 994 void 995 getnewvnode_reserve(u_int count) 996 { 997 struct thread *td; 998 999 td = curthread; 1000 mtx_lock(&vnode_free_list_mtx); 1001 while (count > 0) { 1002 if (getnewvnode_wait(0) == 0) { 1003 count--; 1004 td->td_vp_reserv++; 1005 numvnodes++; 1006 } 1007 } 1008 mtx_unlock(&vnode_free_list_mtx); 1009 } 1010 1011 void 1012 getnewvnode_drop_reserve(void) 1013 { 1014 struct thread *td; 1015 1016 td = curthread; 1017 mtx_lock(&vnode_free_list_mtx); 1018 KASSERT(numvnodes >= td->td_vp_reserv, ("reserve too large")); 1019 numvnodes -= td->td_vp_reserv; 1020 mtx_unlock(&vnode_free_list_mtx); 1021 td->td_vp_reserv = 0; 1022 } 1023 1024 /* 1025 * Return the next vnode from the free list. 1026 */ 1027 int 1028 getnewvnode(const char *tag, struct mount *mp, struct vop_vector *vops, 1029 struct vnode **vpp) 1030 { 1031 struct vnode *vp; 1032 struct bufobj *bo; 1033 struct thread *td; 1034 int error; 1035 1036 CTR3(KTR_VFS, "%s: mp %p with tag %s", __func__, mp, tag); 1037 vp = NULL; 1038 td = curthread; 1039 if (td->td_vp_reserv > 0) { 1040 td->td_vp_reserv -= 1; 1041 goto alloc; 1042 } 1043 mtx_lock(&vnode_free_list_mtx); 1044 /* 1045 * Lend our context to reclaim vnodes if they've exceeded the max. 1046 */ 1047 if (freevnodes > wantfreevnodes) 1048 vnlru_free(1); 1049 error = getnewvnode_wait(mp != NULL && (mp->mnt_kern_flag & 1050 MNTK_SUSPEND)); 1051 #if 0 /* XXX Not all VFS_VGET/ffs_vget callers check returns. */ 1052 if (error != 0) { 1053 mtx_unlock(&vnode_free_list_mtx); 1054 return (error); 1055 } 1056 #endif 1057 numvnodes++; 1058 mtx_unlock(&vnode_free_list_mtx); 1059 alloc: 1060 vp = (struct vnode *) uma_zalloc(vnode_zone, M_WAITOK|M_ZERO); 1061 /* 1062 * Setup locks. 1063 */ 1064 vp->v_vnlock = &vp->v_lock; 1065 mtx_init(&vp->v_interlock, "vnode interlock", NULL, MTX_DEF); 1066 /* 1067 * By default, don't allow shared locks unless filesystems 1068 * opt-in. 1069 */ 1070 lockinit(vp->v_vnlock, PVFS, tag, VLKTIMEOUT, LK_NOSHARE | LK_IS_VNODE); 1071 /* 1072 * Initialize bufobj. 1073 */ 1074 bo = &vp->v_bufobj; 1075 bo->__bo_vnode = vp; 1076 mtx_init(BO_MTX(bo), "bufobj interlock", NULL, MTX_DEF); 1077 bo->bo_ops = &buf_ops_bio; 1078 bo->bo_private = vp; 1079 TAILQ_INIT(&bo->bo_clean.bv_hd); 1080 TAILQ_INIT(&bo->bo_dirty.bv_hd); 1081 /* 1082 * Initialize namecache. 1083 */ 1084 LIST_INIT(&vp->v_cache_src); 1085 TAILQ_INIT(&vp->v_cache_dst); 1086 /* 1087 * Finalize various vnode identity bits. 1088 */ 1089 vp->v_type = VNON; 1090 vp->v_tag = tag; 1091 vp->v_op = vops; 1092 v_incr_usecount(vp); 1093 vp->v_data = NULL; 1094 #ifdef MAC 1095 mac_vnode_init(vp); 1096 if (mp != NULL && (mp->mnt_flag & MNT_MULTILABEL) == 0) 1097 mac_vnode_associate_singlelabel(mp, vp); 1098 else if (mp == NULL && vops != &dead_vnodeops) 1099 printf("NULL mp in getnewvnode()\n"); 1100 #endif 1101 if (mp != NULL) { 1102 bo->bo_bsize = mp->mnt_stat.f_iosize; 1103 if ((mp->mnt_kern_flag & MNTK_NOKNOTE) != 0) 1104 vp->v_vflag |= VV_NOKNOTE; 1105 } 1106 rangelock_init(&vp->v_rl); 1107 1108 /* 1109 * For the filesystems which do not use vfs_hash_insert(), 1110 * still initialize v_hash to have vfs_hash_index() useful. 1111 * E.g., nullfs uses vfs_hash_index() on the lower vnode for 1112 * its own hashing. 1113 */ 1114 vp->v_hash = (uintptr_t)vp >> vnsz2log; 1115 1116 *vpp = vp; 1117 return (0); 1118 } 1119 1120 /* 1121 * Delete from old mount point vnode list, if on one. 1122 */ 1123 static void 1124 delmntque(struct vnode *vp) 1125 { 1126 struct mount *mp; 1127 int active; 1128 1129 mp = vp->v_mount; 1130 if (mp == NULL) 1131 return; 1132 MNT_ILOCK(mp); 1133 VI_LOCK(vp); 1134 KASSERT(mp->mnt_activevnodelistsize <= mp->mnt_nvnodelistsize, 1135 ("Active vnode list size %d > Vnode list size %d", 1136 mp->mnt_activevnodelistsize, mp->mnt_nvnodelistsize)); 1137 active = vp->v_iflag & VI_ACTIVE; 1138 vp->v_iflag &= ~VI_ACTIVE; 1139 if (active) { 1140 mtx_lock(&vnode_free_list_mtx); 1141 TAILQ_REMOVE(&mp->mnt_activevnodelist, vp, v_actfreelist); 1142 mp->mnt_activevnodelistsize--; 1143 mtx_unlock(&vnode_free_list_mtx); 1144 } 1145 vp->v_mount = NULL; 1146 VI_UNLOCK(vp); 1147 VNASSERT(mp->mnt_nvnodelistsize > 0, vp, 1148 ("bad mount point vnode list size")); 1149 TAILQ_REMOVE(&mp->mnt_nvnodelist, vp, v_nmntvnodes); 1150 mp->mnt_nvnodelistsize--; 1151 MNT_REL(mp); 1152 MNT_IUNLOCK(mp); 1153 } 1154 1155 static void 1156 insmntque_stddtr(struct vnode *vp, void *dtr_arg) 1157 { 1158 1159 vp->v_data = NULL; 1160 vp->v_op = &dead_vnodeops; 1161 vgone(vp); 1162 vput(vp); 1163 } 1164 1165 /* 1166 * Insert into list of vnodes for the new mount point, if available. 1167 */ 1168 int 1169 insmntque1(struct vnode *vp, struct mount *mp, 1170 void (*dtr)(struct vnode *, void *), void *dtr_arg) 1171 { 1172 1173 KASSERT(vp->v_mount == NULL, 1174 ("insmntque: vnode already on per mount vnode list")); 1175 VNASSERT(mp != NULL, vp, ("Don't call insmntque(foo, NULL)")); 1176 ASSERT_VOP_ELOCKED(vp, "insmntque: non-locked vp"); 1177 1178 /* 1179 * We acquire the vnode interlock early to ensure that the 1180 * vnode cannot be recycled by another process releasing a 1181 * holdcnt on it before we get it on both the vnode list 1182 * and the active vnode list. The mount mutex protects only 1183 * manipulation of the vnode list and the vnode freelist 1184 * mutex protects only manipulation of the active vnode list. 1185 * Hence the need to hold the vnode interlock throughout. 1186 */ 1187 MNT_ILOCK(mp); 1188 VI_LOCK(vp); 1189 if (((mp->mnt_kern_flag & MNTK_NOINSMNTQ) != 0 && 1190 ((mp->mnt_kern_flag & MNTK_UNMOUNTF) != 0 || 1191 mp->mnt_nvnodelistsize == 0)) && 1192 (vp->v_vflag & VV_FORCEINSMQ) == 0) { 1193 VI_UNLOCK(vp); 1194 MNT_IUNLOCK(mp); 1195 if (dtr != NULL) 1196 dtr(vp, dtr_arg); 1197 return (EBUSY); 1198 } 1199 vp->v_mount = mp; 1200 MNT_REF(mp); 1201 TAILQ_INSERT_TAIL(&mp->mnt_nvnodelist, vp, v_nmntvnodes); 1202 VNASSERT(mp->mnt_nvnodelistsize >= 0, vp, 1203 ("neg mount point vnode list size")); 1204 mp->mnt_nvnodelistsize++; 1205 KASSERT((vp->v_iflag & VI_ACTIVE) == 0, 1206 ("Activating already active vnode")); 1207 vp->v_iflag |= VI_ACTIVE; 1208 mtx_lock(&vnode_free_list_mtx); 1209 TAILQ_INSERT_HEAD(&mp->mnt_activevnodelist, vp, v_actfreelist); 1210 mp->mnt_activevnodelistsize++; 1211 mtx_unlock(&vnode_free_list_mtx); 1212 VI_UNLOCK(vp); 1213 MNT_IUNLOCK(mp); 1214 return (0); 1215 } 1216 1217 int 1218 insmntque(struct vnode *vp, struct mount *mp) 1219 { 1220 1221 return (insmntque1(vp, mp, insmntque_stddtr, NULL)); 1222 } 1223 1224 /* 1225 * Flush out and invalidate all buffers associated with a bufobj 1226 * Called with the underlying object locked. 1227 */ 1228 int 1229 bufobj_invalbuf(struct bufobj *bo, int flags, int slpflag, int slptimeo) 1230 { 1231 int error; 1232 1233 BO_LOCK(bo); 1234 if (flags & V_SAVE) { 1235 error = bufobj_wwait(bo, slpflag, slptimeo); 1236 if (error) { 1237 BO_UNLOCK(bo); 1238 return (error); 1239 } 1240 if (bo->bo_dirty.bv_cnt > 0) { 1241 BO_UNLOCK(bo); 1242 if ((error = BO_SYNC(bo, MNT_WAIT)) != 0) 1243 return (error); 1244 /* 1245 * XXX We could save a lock/unlock if this was only 1246 * enabled under INVARIANTS 1247 */ 1248 BO_LOCK(bo); 1249 if (bo->bo_numoutput > 0 || bo->bo_dirty.bv_cnt > 0) 1250 panic("vinvalbuf: dirty bufs"); 1251 } 1252 } 1253 /* 1254 * If you alter this loop please notice that interlock is dropped and 1255 * reacquired in flushbuflist. Special care is needed to ensure that 1256 * no race conditions occur from this. 1257 */ 1258 do { 1259 error = flushbuflist(&bo->bo_clean, 1260 flags, bo, slpflag, slptimeo); 1261 if (error == 0 && !(flags & V_CLEANONLY)) 1262 error = flushbuflist(&bo->bo_dirty, 1263 flags, bo, slpflag, slptimeo); 1264 if (error != 0 && error != EAGAIN) { 1265 BO_UNLOCK(bo); 1266 return (error); 1267 } 1268 } while (error != 0); 1269 1270 /* 1271 * Wait for I/O to complete. XXX needs cleaning up. The vnode can 1272 * have write I/O in-progress but if there is a VM object then the 1273 * VM object can also have read-I/O in-progress. 1274 */ 1275 do { 1276 bufobj_wwait(bo, 0, 0); 1277 BO_UNLOCK(bo); 1278 if (bo->bo_object != NULL) { 1279 VM_OBJECT_WLOCK(bo->bo_object); 1280 vm_object_pip_wait(bo->bo_object, "bovlbx"); 1281 VM_OBJECT_WUNLOCK(bo->bo_object); 1282 } 1283 BO_LOCK(bo); 1284 } while (bo->bo_numoutput > 0); 1285 BO_UNLOCK(bo); 1286 1287 /* 1288 * Destroy the copy in the VM cache, too. 1289 */ 1290 if (bo->bo_object != NULL && 1291 (flags & (V_ALT | V_NORMAL | V_CLEANONLY)) == 0) { 1292 VM_OBJECT_WLOCK(bo->bo_object); 1293 vm_object_page_remove(bo->bo_object, 0, 0, (flags & V_SAVE) ? 1294 OBJPR_CLEANONLY : 0); 1295 VM_OBJECT_WUNLOCK(bo->bo_object); 1296 } 1297 1298 #ifdef INVARIANTS 1299 BO_LOCK(bo); 1300 if ((flags & (V_ALT | V_NORMAL | V_CLEANONLY)) == 0 && 1301 (bo->bo_dirty.bv_cnt > 0 || bo->bo_clean.bv_cnt > 0)) 1302 panic("vinvalbuf: flush failed"); 1303 BO_UNLOCK(bo); 1304 #endif 1305 return (0); 1306 } 1307 1308 /* 1309 * Flush out and invalidate all buffers associated with a vnode. 1310 * Called with the underlying object locked. 1311 */ 1312 int 1313 vinvalbuf(struct vnode *vp, int flags, int slpflag, int slptimeo) 1314 { 1315 1316 CTR3(KTR_VFS, "%s: vp %p with flags %d", __func__, vp, flags); 1317 ASSERT_VOP_LOCKED(vp, "vinvalbuf"); 1318 return (bufobj_invalbuf(&vp->v_bufobj, flags, slpflag, slptimeo)); 1319 } 1320 1321 /* 1322 * Flush out buffers on the specified list. 1323 * 1324 */ 1325 static int 1326 flushbuflist(struct bufv *bufv, int flags, struct bufobj *bo, int slpflag, 1327 int slptimeo) 1328 { 1329 struct buf *bp, *nbp; 1330 int retval, error; 1331 daddr_t lblkno; 1332 b_xflags_t xflags; 1333 1334 ASSERT_BO_LOCKED(bo); 1335 1336 retval = 0; 1337 TAILQ_FOREACH_SAFE(bp, &bufv->bv_hd, b_bobufs, nbp) { 1338 if (((flags & V_NORMAL) && (bp->b_xflags & BX_ALTDATA)) || 1339 ((flags & V_ALT) && (bp->b_xflags & BX_ALTDATA) == 0)) { 1340 continue; 1341 } 1342 lblkno = 0; 1343 xflags = 0; 1344 if (nbp != NULL) { 1345 lblkno = nbp->b_lblkno; 1346 xflags = nbp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN); 1347 } 1348 retval = EAGAIN; 1349 error = BUF_TIMELOCK(bp, 1350 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, BO_MTX(bo), 1351 "flushbuf", slpflag, slptimeo); 1352 if (error) { 1353 BO_LOCK(bo); 1354 return (error != ENOLCK ? error : EAGAIN); 1355 } 1356 KASSERT(bp->b_bufobj == bo, 1357 ("bp %p wrong b_bufobj %p should be %p", 1358 bp, bp->b_bufobj, bo)); 1359 if (bp->b_bufobj != bo) { /* XXX: necessary ? */ 1360 BUF_UNLOCK(bp); 1361 BO_LOCK(bo); 1362 return (EAGAIN); 1363 } 1364 /* 1365 * XXX Since there are no node locks for NFS, I 1366 * believe there is a slight chance that a delayed 1367 * write will occur while sleeping just above, so 1368 * check for it. 1369 */ 1370 if (((bp->b_flags & (B_DELWRI | B_INVAL)) == B_DELWRI) && 1371 (flags & V_SAVE)) { 1372 BO_LOCK(bo); 1373 bremfree(bp); 1374 BO_UNLOCK(bo); 1375 bp->b_flags |= B_ASYNC; 1376 bwrite(bp); 1377 BO_LOCK(bo); 1378 return (EAGAIN); /* XXX: why not loop ? */ 1379 } 1380 BO_LOCK(bo); 1381 bremfree(bp); 1382 BO_UNLOCK(bo); 1383 bp->b_flags |= (B_INVAL | B_RELBUF); 1384 bp->b_flags &= ~B_ASYNC; 1385 brelse(bp); 1386 BO_LOCK(bo); 1387 if (nbp != NULL && 1388 (nbp->b_bufobj != bo || 1389 nbp->b_lblkno != lblkno || 1390 (nbp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN)) != xflags)) 1391 break; /* nbp invalid */ 1392 } 1393 return (retval); 1394 } 1395 1396 /* 1397 * Truncate a file's buffer and pages to a specified length. This 1398 * is in lieu of the old vinvalbuf mechanism, which performed unneeded 1399 * sync activity. 1400 */ 1401 int 1402 vtruncbuf(struct vnode *vp, struct ucred *cred, off_t length, int blksize) 1403 { 1404 struct buf *bp, *nbp; 1405 int anyfreed; 1406 int trunclbn; 1407 struct bufobj *bo; 1408 1409 CTR5(KTR_VFS, "%s: vp %p with cred %p and block %d:%ju", __func__, 1410 vp, cred, blksize, (uintmax_t)length); 1411 1412 /* 1413 * Round up to the *next* lbn. 1414 */ 1415 trunclbn = (length + blksize - 1) / blksize; 1416 1417 ASSERT_VOP_LOCKED(vp, "vtruncbuf"); 1418 restart: 1419 bo = &vp->v_bufobj; 1420 BO_LOCK(bo); 1421 anyfreed = 1; 1422 for (;anyfreed;) { 1423 anyfreed = 0; 1424 TAILQ_FOREACH_SAFE(bp, &bo->bo_clean.bv_hd, b_bobufs, nbp) { 1425 if (bp->b_lblkno < trunclbn) 1426 continue; 1427 if (BUF_LOCK(bp, 1428 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, 1429 BO_MTX(bo)) == ENOLCK) 1430 goto restart; 1431 1432 BO_LOCK(bo); 1433 bremfree(bp); 1434 BO_UNLOCK(bo); 1435 bp->b_flags |= (B_INVAL | B_RELBUF); 1436 bp->b_flags &= ~B_ASYNC; 1437 brelse(bp); 1438 anyfreed = 1; 1439 1440 BO_LOCK(bo); 1441 if (nbp != NULL && 1442 (((nbp->b_xflags & BX_VNCLEAN) == 0) || 1443 (nbp->b_vp != vp) || 1444 (nbp->b_flags & B_DELWRI))) { 1445 BO_UNLOCK(bo); 1446 goto restart; 1447 } 1448 } 1449 1450 TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) { 1451 if (bp->b_lblkno < trunclbn) 1452 continue; 1453 if (BUF_LOCK(bp, 1454 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, 1455 BO_MTX(bo)) == ENOLCK) 1456 goto restart; 1457 BO_LOCK(bo); 1458 bremfree(bp); 1459 BO_UNLOCK(bo); 1460 bp->b_flags |= (B_INVAL | B_RELBUF); 1461 bp->b_flags &= ~B_ASYNC; 1462 brelse(bp); 1463 anyfreed = 1; 1464 1465 BO_LOCK(bo); 1466 if (nbp != NULL && 1467 (((nbp->b_xflags & BX_VNDIRTY) == 0) || 1468 (nbp->b_vp != vp) || 1469 (nbp->b_flags & B_DELWRI) == 0)) { 1470 BO_UNLOCK(bo); 1471 goto restart; 1472 } 1473 } 1474 } 1475 1476 if (length > 0) { 1477 restartsync: 1478 TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) { 1479 if (bp->b_lblkno > 0) 1480 continue; 1481 /* 1482 * Since we hold the vnode lock this should only 1483 * fail if we're racing with the buf daemon. 1484 */ 1485 if (BUF_LOCK(bp, 1486 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, 1487 BO_MTX(bo)) == ENOLCK) { 1488 goto restart; 1489 } 1490 VNASSERT((bp->b_flags & B_DELWRI), vp, 1491 ("buf(%p) on dirty queue without DELWRI", bp)); 1492 1493 BO_LOCK(bo); 1494 bremfree(bp); 1495 BO_UNLOCK(bo); 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_LOCKED(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_LOCKED(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_LOCKED(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_LOCKED(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 = EBUSY; 2233 break; 2234 } 2235 if (vp->v_usecount > 0) 2236 vp->v_iflag &= ~VI_OWEINACT; 2237 if (error == 0) { 2238 if (vp->v_iflag & VI_OWEINACT) 2239 vinactive(vp, curthread); 2240 if (func != VPUTX_VUNREF) 2241 VOP_UNLOCK(vp, 0); 2242 } 2243 vdropl(vp); 2244 } 2245 2246 /* 2247 * Vnode put/release. 2248 * If count drops to zero, call inactive routine and return to freelist. 2249 */ 2250 void 2251 vrele(struct vnode *vp) 2252 { 2253 2254 vputx(vp, VPUTX_VRELE); 2255 } 2256 2257 /* 2258 * Release an already locked vnode. This give the same effects as 2259 * unlock+vrele(), but takes less time and avoids releasing and 2260 * re-aquiring the lock (as vrele() acquires the lock internally.) 2261 */ 2262 void 2263 vput(struct vnode *vp) 2264 { 2265 2266 vputx(vp, VPUTX_VPUT); 2267 } 2268 2269 /* 2270 * Release an exclusively locked vnode. Do not unlock the vnode lock. 2271 */ 2272 void 2273 vunref(struct vnode *vp) 2274 { 2275 2276 vputx(vp, VPUTX_VUNREF); 2277 } 2278 2279 /* 2280 * Somebody doesn't want the vnode recycled. 2281 */ 2282 void 2283 vhold(struct vnode *vp) 2284 { 2285 2286 VI_LOCK(vp); 2287 vholdl(vp); 2288 VI_UNLOCK(vp); 2289 } 2290 2291 /* 2292 * Increase the hold count and activate if this is the first reference. 2293 */ 2294 void 2295 vholdl(struct vnode *vp) 2296 { 2297 struct mount *mp; 2298 2299 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2300 vp->v_holdcnt++; 2301 if (!VSHOULDBUSY(vp)) 2302 return; 2303 ASSERT_VI_LOCKED(vp, "vholdl"); 2304 VNASSERT((vp->v_iflag & VI_FREE) != 0, vp, ("vnode not free")); 2305 VNASSERT(vp->v_op != NULL, vp, ("vholdl: vnode already reclaimed.")); 2306 /* 2307 * Remove a vnode from the free list, mark it as in use, 2308 * and put it on the active list. 2309 */ 2310 mtx_lock(&vnode_free_list_mtx); 2311 TAILQ_REMOVE(&vnode_free_list, vp, v_actfreelist); 2312 freevnodes--; 2313 vp->v_iflag &= ~(VI_FREE|VI_AGE); 2314 KASSERT((vp->v_iflag & VI_ACTIVE) == 0, 2315 ("Activating already active vnode")); 2316 vp->v_iflag |= VI_ACTIVE; 2317 mp = vp->v_mount; 2318 TAILQ_INSERT_HEAD(&mp->mnt_activevnodelist, vp, v_actfreelist); 2319 mp->mnt_activevnodelistsize++; 2320 mtx_unlock(&vnode_free_list_mtx); 2321 } 2322 2323 /* 2324 * Note that there is one less who cares about this vnode. 2325 * vdrop() is the opposite of vhold(). 2326 */ 2327 void 2328 vdrop(struct vnode *vp) 2329 { 2330 2331 VI_LOCK(vp); 2332 vdropl(vp); 2333 } 2334 2335 /* 2336 * Drop the hold count of the vnode. If this is the last reference to 2337 * the vnode we place it on the free list unless it has been vgone'd 2338 * (marked VI_DOOMED) in which case we will free it. 2339 */ 2340 void 2341 vdropl(struct vnode *vp) 2342 { 2343 struct bufobj *bo; 2344 struct mount *mp; 2345 int active; 2346 2347 ASSERT_VI_LOCKED(vp, "vdropl"); 2348 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2349 if (vp->v_holdcnt <= 0) 2350 panic("vdrop: holdcnt %d", vp->v_holdcnt); 2351 vp->v_holdcnt--; 2352 if (vp->v_holdcnt > 0) { 2353 VI_UNLOCK(vp); 2354 return; 2355 } 2356 if ((vp->v_iflag & VI_DOOMED) == 0) { 2357 /* 2358 * Mark a vnode as free: remove it from its active list 2359 * and put it up for recycling on the freelist. 2360 */ 2361 VNASSERT(vp->v_op != NULL, vp, 2362 ("vdropl: vnode already reclaimed.")); 2363 VNASSERT((vp->v_iflag & VI_FREE) == 0, vp, 2364 ("vnode already free")); 2365 VNASSERT(VSHOULDFREE(vp), vp, 2366 ("vdropl: freeing when we shouldn't")); 2367 active = vp->v_iflag & VI_ACTIVE; 2368 vp->v_iflag &= ~VI_ACTIVE; 2369 mp = vp->v_mount; 2370 mtx_lock(&vnode_free_list_mtx); 2371 if (active) { 2372 TAILQ_REMOVE(&mp->mnt_activevnodelist, vp, 2373 v_actfreelist); 2374 mp->mnt_activevnodelistsize--; 2375 } 2376 if (vp->v_iflag & VI_AGE) { 2377 TAILQ_INSERT_HEAD(&vnode_free_list, vp, v_actfreelist); 2378 } else { 2379 TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_actfreelist); 2380 } 2381 freevnodes++; 2382 vp->v_iflag &= ~VI_AGE; 2383 vp->v_iflag |= VI_FREE; 2384 mtx_unlock(&vnode_free_list_mtx); 2385 VI_UNLOCK(vp); 2386 return; 2387 } 2388 /* 2389 * The vnode has been marked for destruction, so free it. 2390 */ 2391 CTR2(KTR_VFS, "%s: destroying the vnode %p", __func__, vp); 2392 mtx_lock(&vnode_free_list_mtx); 2393 numvnodes--; 2394 mtx_unlock(&vnode_free_list_mtx); 2395 bo = &vp->v_bufobj; 2396 VNASSERT((vp->v_iflag & VI_FREE) == 0, vp, 2397 ("cleaned vnode still on the free list.")); 2398 VNASSERT(vp->v_data == NULL, vp, ("cleaned vnode isn't")); 2399 VNASSERT(vp->v_holdcnt == 0, vp, ("Non-zero hold count")); 2400 VNASSERT(vp->v_usecount == 0, vp, ("Non-zero use count")); 2401 VNASSERT(vp->v_writecount == 0, vp, ("Non-zero write count")); 2402 VNASSERT(bo->bo_numoutput == 0, vp, ("Clean vnode has pending I/O's")); 2403 VNASSERT(bo->bo_clean.bv_cnt == 0, vp, ("cleanbufcnt not 0")); 2404 VNASSERT(pctrie_is_empty(&bo->bo_clean.bv_root), vp, 2405 ("clean blk trie not empty")); 2406 VNASSERT(bo->bo_dirty.bv_cnt == 0, vp, ("dirtybufcnt not 0")); 2407 VNASSERT(pctrie_is_empty(&bo->bo_dirty.bv_root), vp, 2408 ("dirty blk trie not empty")); 2409 VNASSERT(TAILQ_EMPTY(&vp->v_cache_dst), vp, ("vp has namecache dst")); 2410 VNASSERT(LIST_EMPTY(&vp->v_cache_src), vp, ("vp has namecache src")); 2411 VNASSERT(vp->v_cache_dd == NULL, vp, ("vp has namecache for ..")); 2412 VI_UNLOCK(vp); 2413 #ifdef MAC 2414 mac_vnode_destroy(vp); 2415 #endif 2416 if (vp->v_pollinfo != NULL) 2417 destroy_vpollinfo(vp->v_pollinfo); 2418 #ifdef INVARIANTS 2419 /* XXX Elsewhere we detect an already freed vnode via NULL v_op. */ 2420 vp->v_op = NULL; 2421 #endif 2422 rangelock_destroy(&vp->v_rl); 2423 lockdestroy(vp->v_vnlock); 2424 mtx_destroy(&vp->v_interlock); 2425 mtx_destroy(BO_MTX(bo)); 2426 uma_zfree(vnode_zone, vp); 2427 } 2428 2429 /* 2430 * Call VOP_INACTIVE on the vnode and manage the DOINGINACT and OWEINACT 2431 * flags. DOINGINACT prevents us from recursing in calls to vinactive. 2432 * OWEINACT tracks whether a vnode missed a call to inactive due to a 2433 * failed lock upgrade. 2434 */ 2435 void 2436 vinactive(struct vnode *vp, struct thread *td) 2437 { 2438 struct vm_object *obj; 2439 2440 ASSERT_VOP_ELOCKED(vp, "vinactive"); 2441 ASSERT_VI_LOCKED(vp, "vinactive"); 2442 VNASSERT((vp->v_iflag & VI_DOINGINACT) == 0, vp, 2443 ("vinactive: recursed on VI_DOINGINACT")); 2444 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2445 vp->v_iflag |= VI_DOINGINACT; 2446 vp->v_iflag &= ~VI_OWEINACT; 2447 VI_UNLOCK(vp); 2448 /* 2449 * Before moving off the active list, we must be sure that any 2450 * modified pages are on the vnode's dirty list since these will 2451 * no longer be checked once the vnode is on the inactive list. 2452 * Because the vnode vm object keeps a hold reference on the vnode 2453 * if there is at least one resident non-cached page, the vnode 2454 * cannot leave the active list without the page cleanup done. 2455 */ 2456 obj = vp->v_object; 2457 if (obj != NULL && (obj->flags & OBJ_MIGHTBEDIRTY) != 0) { 2458 VM_OBJECT_WLOCK(obj); 2459 vm_object_page_clean(obj, 0, 0, OBJPC_NOSYNC); 2460 VM_OBJECT_WUNLOCK(obj); 2461 } 2462 VOP_INACTIVE(vp, td); 2463 VI_LOCK(vp); 2464 VNASSERT(vp->v_iflag & VI_DOINGINACT, vp, 2465 ("vinactive: lost VI_DOINGINACT")); 2466 vp->v_iflag &= ~VI_DOINGINACT; 2467 } 2468 2469 /* 2470 * Remove any vnodes in the vnode table belonging to mount point mp. 2471 * 2472 * If FORCECLOSE is not specified, there should not be any active ones, 2473 * return error if any are found (nb: this is a user error, not a 2474 * system error). If FORCECLOSE is specified, detach any active vnodes 2475 * that are found. 2476 * 2477 * If WRITECLOSE is set, only flush out regular file vnodes open for 2478 * writing. 2479 * 2480 * SKIPSYSTEM causes any vnodes marked VV_SYSTEM to be skipped. 2481 * 2482 * `rootrefs' specifies the base reference count for the root vnode 2483 * of this filesystem. The root vnode is considered busy if its 2484 * v_usecount exceeds this value. On a successful return, vflush(, td) 2485 * will call vrele() on the root vnode exactly rootrefs times. 2486 * If the SKIPSYSTEM or WRITECLOSE flags are specified, rootrefs must 2487 * be zero. 2488 */ 2489 #ifdef DIAGNOSTIC 2490 static int busyprt = 0; /* print out busy vnodes */ 2491 SYSCTL_INT(_debug, OID_AUTO, busyprt, CTLFLAG_RW, &busyprt, 0, "Print out busy vnodes"); 2492 #endif 2493 2494 int 2495 vflush(struct mount *mp, int rootrefs, int flags, struct thread *td) 2496 { 2497 struct vnode *vp, *mvp, *rootvp = NULL; 2498 struct vattr vattr; 2499 int busy = 0, error; 2500 2501 CTR4(KTR_VFS, "%s: mp %p with rootrefs %d and flags %d", __func__, mp, 2502 rootrefs, flags); 2503 if (rootrefs > 0) { 2504 KASSERT((flags & (SKIPSYSTEM | WRITECLOSE)) == 0, 2505 ("vflush: bad args")); 2506 /* 2507 * Get the filesystem root vnode. We can vput() it 2508 * immediately, since with rootrefs > 0, it won't go away. 2509 */ 2510 if ((error = VFS_ROOT(mp, LK_EXCLUSIVE, &rootvp)) != 0) { 2511 CTR2(KTR_VFS, "%s: vfs_root lookup failed with %d", 2512 __func__, error); 2513 return (error); 2514 } 2515 vput(rootvp); 2516 } 2517 loop: 2518 MNT_VNODE_FOREACH_ALL(vp, mp, mvp) { 2519 vholdl(vp); 2520 error = vn_lock(vp, LK_INTERLOCK | LK_EXCLUSIVE); 2521 if (error) { 2522 vdrop(vp); 2523 MNT_VNODE_FOREACH_ALL_ABORT(mp, mvp); 2524 goto loop; 2525 } 2526 /* 2527 * Skip over a vnodes marked VV_SYSTEM. 2528 */ 2529 if ((flags & SKIPSYSTEM) && (vp->v_vflag & VV_SYSTEM)) { 2530 VOP_UNLOCK(vp, 0); 2531 vdrop(vp); 2532 continue; 2533 } 2534 /* 2535 * If WRITECLOSE is set, flush out unlinked but still open 2536 * files (even if open only for reading) and regular file 2537 * vnodes open for writing. 2538 */ 2539 if (flags & WRITECLOSE) { 2540 if (vp->v_object != NULL) { 2541 VM_OBJECT_WLOCK(vp->v_object); 2542 vm_object_page_clean(vp->v_object, 0, 0, 0); 2543 VM_OBJECT_WUNLOCK(vp->v_object); 2544 } 2545 error = VOP_FSYNC(vp, MNT_WAIT, td); 2546 if (error != 0) { 2547 VOP_UNLOCK(vp, 0); 2548 vdrop(vp); 2549 MNT_VNODE_FOREACH_ALL_ABORT(mp, mvp); 2550 return (error); 2551 } 2552 error = VOP_GETATTR(vp, &vattr, td->td_ucred); 2553 VI_LOCK(vp); 2554 2555 if ((vp->v_type == VNON || 2556 (error == 0 && vattr.va_nlink > 0)) && 2557 (vp->v_writecount == 0 || vp->v_type != VREG)) { 2558 VOP_UNLOCK(vp, 0); 2559 vdropl(vp); 2560 continue; 2561 } 2562 } else 2563 VI_LOCK(vp); 2564 /* 2565 * With v_usecount == 0, all we need to do is clear out the 2566 * vnode data structures and we are done. 2567 * 2568 * If FORCECLOSE is set, forcibly close the vnode. 2569 */ 2570 if (vp->v_usecount == 0 || (flags & FORCECLOSE)) { 2571 VNASSERT(vp->v_usecount == 0 || 2572 (vp->v_type != VCHR && vp->v_type != VBLK), vp, 2573 ("device VNODE %p is FORCECLOSED", vp)); 2574 vgonel(vp); 2575 } else { 2576 busy++; 2577 #ifdef DIAGNOSTIC 2578 if (busyprt) 2579 vprint("vflush: busy vnode", vp); 2580 #endif 2581 } 2582 VOP_UNLOCK(vp, 0); 2583 vdropl(vp); 2584 } 2585 if (rootrefs > 0 && (flags & FORCECLOSE) == 0) { 2586 /* 2587 * If just the root vnode is busy, and if its refcount 2588 * is equal to `rootrefs', then go ahead and kill it. 2589 */ 2590 VI_LOCK(rootvp); 2591 KASSERT(busy > 0, ("vflush: not busy")); 2592 VNASSERT(rootvp->v_usecount >= rootrefs, rootvp, 2593 ("vflush: usecount %d < rootrefs %d", 2594 rootvp->v_usecount, rootrefs)); 2595 if (busy == 1 && rootvp->v_usecount == rootrefs) { 2596 VOP_LOCK(rootvp, LK_EXCLUSIVE|LK_INTERLOCK); 2597 vgone(rootvp); 2598 VOP_UNLOCK(rootvp, 0); 2599 busy = 0; 2600 } else 2601 VI_UNLOCK(rootvp); 2602 } 2603 if (busy) { 2604 CTR2(KTR_VFS, "%s: failing as %d vnodes are busy", __func__, 2605 busy); 2606 return (EBUSY); 2607 } 2608 for (; rootrefs > 0; rootrefs--) 2609 vrele(rootvp); 2610 return (0); 2611 } 2612 2613 /* 2614 * Recycle an unused vnode to the front of the free list. 2615 */ 2616 int 2617 vrecycle(struct vnode *vp) 2618 { 2619 int recycled; 2620 2621 ASSERT_VOP_ELOCKED(vp, "vrecycle"); 2622 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2623 recycled = 0; 2624 VI_LOCK(vp); 2625 if (vp->v_usecount == 0) { 2626 recycled = 1; 2627 vgonel(vp); 2628 } 2629 VI_UNLOCK(vp); 2630 return (recycled); 2631 } 2632 2633 /* 2634 * Eliminate all activity associated with a vnode 2635 * in preparation for reuse. 2636 */ 2637 void 2638 vgone(struct vnode *vp) 2639 { 2640 VI_LOCK(vp); 2641 vgonel(vp); 2642 VI_UNLOCK(vp); 2643 } 2644 2645 static void 2646 notify_lowervp_vfs_dummy(struct mount *mp __unused, 2647 struct vnode *lowervp __unused) 2648 { 2649 } 2650 2651 /* 2652 * Notify upper mounts about reclaimed or unlinked vnode. 2653 */ 2654 void 2655 vfs_notify_upper(struct vnode *vp, int event) 2656 { 2657 static struct vfsops vgonel_vfsops = { 2658 .vfs_reclaim_lowervp = notify_lowervp_vfs_dummy, 2659 .vfs_unlink_lowervp = notify_lowervp_vfs_dummy, 2660 }; 2661 struct mount *mp, *ump, *mmp; 2662 2663 mp = vp->v_mount; 2664 if (mp == NULL) 2665 return; 2666 2667 MNT_ILOCK(mp); 2668 if (TAILQ_EMPTY(&mp->mnt_uppers)) 2669 goto unlock; 2670 MNT_IUNLOCK(mp); 2671 mmp = malloc(sizeof(struct mount), M_TEMP, M_WAITOK | M_ZERO); 2672 mmp->mnt_op = &vgonel_vfsops; 2673 mmp->mnt_kern_flag |= MNTK_MARKER; 2674 MNT_ILOCK(mp); 2675 mp->mnt_kern_flag |= MNTK_VGONE_UPPER; 2676 for (ump = TAILQ_FIRST(&mp->mnt_uppers); ump != NULL;) { 2677 if ((ump->mnt_kern_flag & MNTK_MARKER) != 0) { 2678 ump = TAILQ_NEXT(ump, mnt_upper_link); 2679 continue; 2680 } 2681 TAILQ_INSERT_AFTER(&mp->mnt_uppers, ump, mmp, mnt_upper_link); 2682 MNT_IUNLOCK(mp); 2683 switch (event) { 2684 case VFS_NOTIFY_UPPER_RECLAIM: 2685 VFS_RECLAIM_LOWERVP(ump, vp); 2686 break; 2687 case VFS_NOTIFY_UPPER_UNLINK: 2688 VFS_UNLINK_LOWERVP(ump, vp); 2689 break; 2690 default: 2691 KASSERT(0, ("invalid event %d", event)); 2692 break; 2693 } 2694 MNT_ILOCK(mp); 2695 ump = TAILQ_NEXT(mmp, mnt_upper_link); 2696 TAILQ_REMOVE(&mp->mnt_uppers, mmp, mnt_upper_link); 2697 } 2698 free(mmp, M_TEMP); 2699 mp->mnt_kern_flag &= ~MNTK_VGONE_UPPER; 2700 if ((mp->mnt_kern_flag & MNTK_VGONE_WAITER) != 0) { 2701 mp->mnt_kern_flag &= ~MNTK_VGONE_WAITER; 2702 wakeup(&mp->mnt_uppers); 2703 } 2704 unlock: 2705 MNT_IUNLOCK(mp); 2706 } 2707 2708 /* 2709 * vgone, with the vp interlock held. 2710 */ 2711 void 2712 vgonel(struct vnode *vp) 2713 { 2714 struct thread *td; 2715 int oweinact; 2716 int active; 2717 struct mount *mp; 2718 2719 ASSERT_VOP_ELOCKED(vp, "vgonel"); 2720 ASSERT_VI_LOCKED(vp, "vgonel"); 2721 VNASSERT(vp->v_holdcnt, vp, 2722 ("vgonel: vp %p has no reference.", vp)); 2723 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2724 td = curthread; 2725 2726 /* 2727 * Don't vgonel if we're already doomed. 2728 */ 2729 if (vp->v_iflag & VI_DOOMED) 2730 return; 2731 vp->v_iflag |= VI_DOOMED; 2732 2733 /* 2734 * Check to see if the vnode is in use. If so, we have to call 2735 * VOP_CLOSE() and VOP_INACTIVE(). 2736 */ 2737 active = vp->v_usecount; 2738 oweinact = (vp->v_iflag & VI_OWEINACT); 2739 VI_UNLOCK(vp); 2740 vfs_notify_upper(vp, VFS_NOTIFY_UPPER_RECLAIM); 2741 2742 /* 2743 * Clean out any buffers associated with the vnode. 2744 * If the flush fails, just toss the buffers. 2745 */ 2746 mp = NULL; 2747 if (!TAILQ_EMPTY(&vp->v_bufobj.bo_dirty.bv_hd)) 2748 (void) vn_start_secondary_write(vp, &mp, V_WAIT); 2749 if (vinvalbuf(vp, V_SAVE, 0, 0) != 0) 2750 vinvalbuf(vp, 0, 0, 0); 2751 2752 /* 2753 * If purging an active vnode, it must be closed and 2754 * deactivated before being reclaimed. 2755 */ 2756 if (active) 2757 VOP_CLOSE(vp, FNONBLOCK, NOCRED, td); 2758 if (oweinact || active) { 2759 VI_LOCK(vp); 2760 if ((vp->v_iflag & VI_DOINGINACT) == 0) 2761 vinactive(vp, td); 2762 VI_UNLOCK(vp); 2763 } 2764 if (vp->v_type == VSOCK) 2765 vfs_unp_reclaim(vp); 2766 /* 2767 * Reclaim the vnode. 2768 */ 2769 if (VOP_RECLAIM(vp, td)) 2770 panic("vgone: cannot reclaim"); 2771 if (mp != NULL) 2772 vn_finished_secondary_write(mp); 2773 VNASSERT(vp->v_object == NULL, vp, 2774 ("vop_reclaim left v_object vp=%p, tag=%s", vp, vp->v_tag)); 2775 /* 2776 * Clear the advisory locks and wake up waiting threads. 2777 */ 2778 (void)VOP_ADVLOCKPURGE(vp); 2779 /* 2780 * Delete from old mount point vnode list. 2781 */ 2782 delmntque(vp); 2783 cache_purge(vp); 2784 /* 2785 * Done with purge, reset to the standard lock and invalidate 2786 * the vnode. 2787 */ 2788 VI_LOCK(vp); 2789 vp->v_vnlock = &vp->v_lock; 2790 vp->v_op = &dead_vnodeops; 2791 vp->v_tag = "none"; 2792 vp->v_type = VBAD; 2793 } 2794 2795 /* 2796 * Calculate the total number of references to a special device. 2797 */ 2798 int 2799 vcount(struct vnode *vp) 2800 { 2801 int count; 2802 2803 dev_lock(); 2804 count = vp->v_rdev->si_usecount; 2805 dev_unlock(); 2806 return (count); 2807 } 2808 2809 /* 2810 * Same as above, but using the struct cdev *as argument 2811 */ 2812 int 2813 count_dev(struct cdev *dev) 2814 { 2815 int count; 2816 2817 dev_lock(); 2818 count = dev->si_usecount; 2819 dev_unlock(); 2820 return(count); 2821 } 2822 2823 /* 2824 * Print out a description of a vnode. 2825 */ 2826 static char *typename[] = 2827 {"VNON", "VREG", "VDIR", "VBLK", "VCHR", "VLNK", "VSOCK", "VFIFO", "VBAD", 2828 "VMARKER"}; 2829 2830 void 2831 vn_printf(struct vnode *vp, const char *fmt, ...) 2832 { 2833 va_list ap; 2834 char buf[256], buf2[16]; 2835 u_long flags; 2836 2837 va_start(ap, fmt); 2838 vprintf(fmt, ap); 2839 va_end(ap); 2840 printf("%p: ", (void *)vp); 2841 printf("tag %s, type %s\n", vp->v_tag, typename[vp->v_type]); 2842 printf(" usecount %d, writecount %d, refcount %d mountedhere %p\n", 2843 vp->v_usecount, vp->v_writecount, vp->v_holdcnt, vp->v_mountedhere); 2844 buf[0] = '\0'; 2845 buf[1] = '\0'; 2846 if (vp->v_vflag & VV_ROOT) 2847 strlcat(buf, "|VV_ROOT", sizeof(buf)); 2848 if (vp->v_vflag & VV_ISTTY) 2849 strlcat(buf, "|VV_ISTTY", sizeof(buf)); 2850 if (vp->v_vflag & VV_NOSYNC) 2851 strlcat(buf, "|VV_NOSYNC", sizeof(buf)); 2852 if (vp->v_vflag & VV_ETERNALDEV) 2853 strlcat(buf, "|VV_ETERNALDEV", sizeof(buf)); 2854 if (vp->v_vflag & VV_CACHEDLABEL) 2855 strlcat(buf, "|VV_CACHEDLABEL", sizeof(buf)); 2856 if (vp->v_vflag & VV_TEXT) 2857 strlcat(buf, "|VV_TEXT", sizeof(buf)); 2858 if (vp->v_vflag & VV_COPYONWRITE) 2859 strlcat(buf, "|VV_COPYONWRITE", sizeof(buf)); 2860 if (vp->v_vflag & VV_SYSTEM) 2861 strlcat(buf, "|VV_SYSTEM", sizeof(buf)); 2862 if (vp->v_vflag & VV_PROCDEP) 2863 strlcat(buf, "|VV_PROCDEP", sizeof(buf)); 2864 if (vp->v_vflag & VV_NOKNOTE) 2865 strlcat(buf, "|VV_NOKNOTE", sizeof(buf)); 2866 if (vp->v_vflag & VV_DELETED) 2867 strlcat(buf, "|VV_DELETED", sizeof(buf)); 2868 if (vp->v_vflag & VV_MD) 2869 strlcat(buf, "|VV_MD", sizeof(buf)); 2870 if (vp->v_vflag & VV_FORCEINSMQ) 2871 strlcat(buf, "|VV_FORCEINSMQ", sizeof(buf)); 2872 flags = vp->v_vflag & ~(VV_ROOT | VV_ISTTY | VV_NOSYNC | VV_ETERNALDEV | 2873 VV_CACHEDLABEL | VV_TEXT | VV_COPYONWRITE | VV_SYSTEM | VV_PROCDEP | 2874 VV_NOKNOTE | VV_DELETED | VV_MD | VV_FORCEINSMQ); 2875 if (flags != 0) { 2876 snprintf(buf2, sizeof(buf2), "|VV(0x%lx)", flags); 2877 strlcat(buf, buf2, sizeof(buf)); 2878 } 2879 if (vp->v_iflag & VI_MOUNT) 2880 strlcat(buf, "|VI_MOUNT", sizeof(buf)); 2881 if (vp->v_iflag & VI_AGE) 2882 strlcat(buf, "|VI_AGE", sizeof(buf)); 2883 if (vp->v_iflag & VI_DOOMED) 2884 strlcat(buf, "|VI_DOOMED", sizeof(buf)); 2885 if (vp->v_iflag & VI_FREE) 2886 strlcat(buf, "|VI_FREE", sizeof(buf)); 2887 if (vp->v_iflag & VI_ACTIVE) 2888 strlcat(buf, "|VI_ACTIVE", sizeof(buf)); 2889 if (vp->v_iflag & VI_DOINGINACT) 2890 strlcat(buf, "|VI_DOINGINACT", sizeof(buf)); 2891 if (vp->v_iflag & VI_OWEINACT) 2892 strlcat(buf, "|VI_OWEINACT", sizeof(buf)); 2893 flags = vp->v_iflag & ~(VI_MOUNT | VI_AGE | VI_DOOMED | VI_FREE | 2894 VI_ACTIVE | VI_DOINGINACT | VI_OWEINACT); 2895 if (flags != 0) { 2896 snprintf(buf2, sizeof(buf2), "|VI(0x%lx)", flags); 2897 strlcat(buf, buf2, sizeof(buf)); 2898 } 2899 printf(" flags (%s)\n", buf + 1); 2900 if (mtx_owned(VI_MTX(vp))) 2901 printf(" VI_LOCKed"); 2902 if (vp->v_object != NULL) 2903 printf(" v_object %p ref %d pages %d\n", 2904 vp->v_object, vp->v_object->ref_count, 2905 vp->v_object->resident_page_count); 2906 printf(" "); 2907 lockmgr_printinfo(vp->v_vnlock); 2908 if (vp->v_data != NULL) 2909 VOP_PRINT(vp); 2910 } 2911 2912 #ifdef DDB 2913 /* 2914 * List all of the locked vnodes in the system. 2915 * Called when debugging the kernel. 2916 */ 2917 DB_SHOW_COMMAND(lockedvnods, lockedvnodes) 2918 { 2919 struct mount *mp, *nmp; 2920 struct vnode *vp; 2921 2922 /* 2923 * Note: because this is DDB, we can't obey the locking semantics 2924 * for these structures, which means we could catch an inconsistent 2925 * state and dereference a nasty pointer. Not much to be done 2926 * about that. 2927 */ 2928 db_printf("Locked vnodes\n"); 2929 for (mp = TAILQ_FIRST(&mountlist); mp != NULL; mp = nmp) { 2930 nmp = TAILQ_NEXT(mp, mnt_list); 2931 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) { 2932 if (vp->v_type != VMARKER && 2933 VOP_ISLOCKED(vp)) 2934 vprint("", vp); 2935 } 2936 nmp = TAILQ_NEXT(mp, mnt_list); 2937 } 2938 } 2939 2940 /* 2941 * Show details about the given vnode. 2942 */ 2943 DB_SHOW_COMMAND(vnode, db_show_vnode) 2944 { 2945 struct vnode *vp; 2946 2947 if (!have_addr) 2948 return; 2949 vp = (struct vnode *)addr; 2950 vn_printf(vp, "vnode "); 2951 } 2952 2953 /* 2954 * Show details about the given mount point. 2955 */ 2956 DB_SHOW_COMMAND(mount, db_show_mount) 2957 { 2958 struct mount *mp; 2959 struct vfsopt *opt; 2960 struct statfs *sp; 2961 struct vnode *vp; 2962 char buf[512]; 2963 uint64_t mflags; 2964 u_int flags; 2965 2966 if (!have_addr) { 2967 /* No address given, print short info about all mount points. */ 2968 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 2969 db_printf("%p %s on %s (%s)\n", mp, 2970 mp->mnt_stat.f_mntfromname, 2971 mp->mnt_stat.f_mntonname, 2972 mp->mnt_stat.f_fstypename); 2973 if (db_pager_quit) 2974 break; 2975 } 2976 db_printf("\nMore info: show mount <addr>\n"); 2977 return; 2978 } 2979 2980 mp = (struct mount *)addr; 2981 db_printf("%p %s on %s (%s)\n", mp, mp->mnt_stat.f_mntfromname, 2982 mp->mnt_stat.f_mntonname, mp->mnt_stat.f_fstypename); 2983 2984 buf[0] = '\0'; 2985 mflags = mp->mnt_flag; 2986 #define MNT_FLAG(flag) do { \ 2987 if (mflags & (flag)) { \ 2988 if (buf[0] != '\0') \ 2989 strlcat(buf, ", ", sizeof(buf)); \ 2990 strlcat(buf, (#flag) + 4, sizeof(buf)); \ 2991 mflags &= ~(flag); \ 2992 } \ 2993 } while (0) 2994 MNT_FLAG(MNT_RDONLY); 2995 MNT_FLAG(MNT_SYNCHRONOUS); 2996 MNT_FLAG(MNT_NOEXEC); 2997 MNT_FLAG(MNT_NOSUID); 2998 MNT_FLAG(MNT_NFS4ACLS); 2999 MNT_FLAG(MNT_UNION); 3000 MNT_FLAG(MNT_ASYNC); 3001 MNT_FLAG(MNT_SUIDDIR); 3002 MNT_FLAG(MNT_SOFTDEP); 3003 MNT_FLAG(MNT_NOSYMFOLLOW); 3004 MNT_FLAG(MNT_GJOURNAL); 3005 MNT_FLAG(MNT_MULTILABEL); 3006 MNT_FLAG(MNT_ACLS); 3007 MNT_FLAG(MNT_NOATIME); 3008 MNT_FLAG(MNT_NOCLUSTERR); 3009 MNT_FLAG(MNT_NOCLUSTERW); 3010 MNT_FLAG(MNT_SUJ); 3011 MNT_FLAG(MNT_EXRDONLY); 3012 MNT_FLAG(MNT_EXPORTED); 3013 MNT_FLAG(MNT_DEFEXPORTED); 3014 MNT_FLAG(MNT_EXPORTANON); 3015 MNT_FLAG(MNT_EXKERB); 3016 MNT_FLAG(MNT_EXPUBLIC); 3017 MNT_FLAG(MNT_LOCAL); 3018 MNT_FLAG(MNT_QUOTA); 3019 MNT_FLAG(MNT_ROOTFS); 3020 MNT_FLAG(MNT_USER); 3021 MNT_FLAG(MNT_IGNORE); 3022 MNT_FLAG(MNT_UPDATE); 3023 MNT_FLAG(MNT_DELEXPORT); 3024 MNT_FLAG(MNT_RELOAD); 3025 MNT_FLAG(MNT_FORCE); 3026 MNT_FLAG(MNT_SNAPSHOT); 3027 MNT_FLAG(MNT_BYFSID); 3028 #undef MNT_FLAG 3029 if (mflags != 0) { 3030 if (buf[0] != '\0') 3031 strlcat(buf, ", ", sizeof(buf)); 3032 snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf), 3033 "0x%016jx", mflags); 3034 } 3035 db_printf(" mnt_flag = %s\n", buf); 3036 3037 buf[0] = '\0'; 3038 flags = mp->mnt_kern_flag; 3039 #define MNT_KERN_FLAG(flag) do { \ 3040 if (flags & (flag)) { \ 3041 if (buf[0] != '\0') \ 3042 strlcat(buf, ", ", sizeof(buf)); \ 3043 strlcat(buf, (#flag) + 5, sizeof(buf)); \ 3044 flags &= ~(flag); \ 3045 } \ 3046 } while (0) 3047 MNT_KERN_FLAG(MNTK_UNMOUNTF); 3048 MNT_KERN_FLAG(MNTK_ASYNC); 3049 MNT_KERN_FLAG(MNTK_SOFTDEP); 3050 MNT_KERN_FLAG(MNTK_NOINSMNTQ); 3051 MNT_KERN_FLAG(MNTK_DRAINING); 3052 MNT_KERN_FLAG(MNTK_REFEXPIRE); 3053 MNT_KERN_FLAG(MNTK_EXTENDED_SHARED); 3054 MNT_KERN_FLAG(MNTK_SHARED_WRITES); 3055 MNT_KERN_FLAG(MNTK_NO_IOPF); 3056 MNT_KERN_FLAG(MNTK_VGONE_UPPER); 3057 MNT_KERN_FLAG(MNTK_VGONE_WAITER); 3058 MNT_KERN_FLAG(MNTK_LOOKUP_EXCL_DOTDOT); 3059 MNT_KERN_FLAG(MNTK_MARKER); 3060 MNT_KERN_FLAG(MNTK_NOASYNC); 3061 MNT_KERN_FLAG(MNTK_UNMOUNT); 3062 MNT_KERN_FLAG(MNTK_MWAIT); 3063 MNT_KERN_FLAG(MNTK_SUSPEND); 3064 MNT_KERN_FLAG(MNTK_SUSPEND2); 3065 MNT_KERN_FLAG(MNTK_SUSPENDED); 3066 MNT_KERN_FLAG(MNTK_LOOKUP_SHARED); 3067 MNT_KERN_FLAG(MNTK_NOKNOTE); 3068 #undef MNT_KERN_FLAG 3069 if (flags != 0) { 3070 if (buf[0] != '\0') 3071 strlcat(buf, ", ", sizeof(buf)); 3072 snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf), 3073 "0x%08x", flags); 3074 } 3075 db_printf(" mnt_kern_flag = %s\n", buf); 3076 3077 db_printf(" mnt_opt = "); 3078 opt = TAILQ_FIRST(mp->mnt_opt); 3079 if (opt != NULL) { 3080 db_printf("%s", opt->name); 3081 opt = TAILQ_NEXT(opt, link); 3082 while (opt != NULL) { 3083 db_printf(", %s", opt->name); 3084 opt = TAILQ_NEXT(opt, link); 3085 } 3086 } 3087 db_printf("\n"); 3088 3089 sp = &mp->mnt_stat; 3090 db_printf(" mnt_stat = { version=%u type=%u flags=0x%016jx " 3091 "bsize=%ju iosize=%ju blocks=%ju bfree=%ju bavail=%jd files=%ju " 3092 "ffree=%jd syncwrites=%ju asyncwrites=%ju syncreads=%ju " 3093 "asyncreads=%ju namemax=%u owner=%u fsid=[%d, %d] }\n", 3094 (u_int)sp->f_version, (u_int)sp->f_type, (uintmax_t)sp->f_flags, 3095 (uintmax_t)sp->f_bsize, (uintmax_t)sp->f_iosize, 3096 (uintmax_t)sp->f_blocks, (uintmax_t)sp->f_bfree, 3097 (intmax_t)sp->f_bavail, (uintmax_t)sp->f_files, 3098 (intmax_t)sp->f_ffree, (uintmax_t)sp->f_syncwrites, 3099 (uintmax_t)sp->f_asyncwrites, (uintmax_t)sp->f_syncreads, 3100 (uintmax_t)sp->f_asyncreads, (u_int)sp->f_namemax, 3101 (u_int)sp->f_owner, (int)sp->f_fsid.val[0], (int)sp->f_fsid.val[1]); 3102 3103 db_printf(" mnt_cred = { uid=%u ruid=%u", 3104 (u_int)mp->mnt_cred->cr_uid, (u_int)mp->mnt_cred->cr_ruid); 3105 if (jailed(mp->mnt_cred)) 3106 db_printf(", jail=%d", mp->mnt_cred->cr_prison->pr_id); 3107 db_printf(" }\n"); 3108 db_printf(" mnt_ref = %d\n", mp->mnt_ref); 3109 db_printf(" mnt_gen = %d\n", mp->mnt_gen); 3110 db_printf(" mnt_nvnodelistsize = %d\n", mp->mnt_nvnodelistsize); 3111 db_printf(" mnt_activevnodelistsize = %d\n", 3112 mp->mnt_activevnodelistsize); 3113 db_printf(" mnt_writeopcount = %d\n", mp->mnt_writeopcount); 3114 db_printf(" mnt_maxsymlinklen = %d\n", mp->mnt_maxsymlinklen); 3115 db_printf(" mnt_iosize_max = %d\n", mp->mnt_iosize_max); 3116 db_printf(" mnt_hashseed = %u\n", mp->mnt_hashseed); 3117 db_printf(" mnt_secondary_writes = %d\n", mp->mnt_secondary_writes); 3118 db_printf(" mnt_secondary_accwrites = %d\n", 3119 mp->mnt_secondary_accwrites); 3120 db_printf(" mnt_gjprovider = %s\n", 3121 mp->mnt_gjprovider != NULL ? mp->mnt_gjprovider : "NULL"); 3122 3123 db_printf("\n\nList of active vnodes\n"); 3124 TAILQ_FOREACH(vp, &mp->mnt_activevnodelist, v_actfreelist) { 3125 if (vp->v_type != VMARKER) { 3126 vn_printf(vp, "vnode "); 3127 if (db_pager_quit) 3128 break; 3129 } 3130 } 3131 db_printf("\n\nList of inactive vnodes\n"); 3132 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) { 3133 if (vp->v_type != VMARKER && (vp->v_iflag & VI_ACTIVE) == 0) { 3134 vn_printf(vp, "vnode "); 3135 if (db_pager_quit) 3136 break; 3137 } 3138 } 3139 } 3140 #endif /* DDB */ 3141 3142 /* 3143 * Fill in a struct xvfsconf based on a struct vfsconf. 3144 */ 3145 static int 3146 vfsconf2x(struct sysctl_req *req, struct vfsconf *vfsp) 3147 { 3148 struct xvfsconf xvfsp; 3149 3150 bzero(&xvfsp, sizeof(xvfsp)); 3151 strcpy(xvfsp.vfc_name, vfsp->vfc_name); 3152 xvfsp.vfc_typenum = vfsp->vfc_typenum; 3153 xvfsp.vfc_refcount = vfsp->vfc_refcount; 3154 xvfsp.vfc_flags = vfsp->vfc_flags; 3155 /* 3156 * These are unused in userland, we keep them 3157 * to not break binary compatibility. 3158 */ 3159 xvfsp.vfc_vfsops = NULL; 3160 xvfsp.vfc_next = NULL; 3161 return (SYSCTL_OUT(req, &xvfsp, sizeof(xvfsp))); 3162 } 3163 3164 #ifdef COMPAT_FREEBSD32 3165 struct xvfsconf32 { 3166 uint32_t vfc_vfsops; 3167 char vfc_name[MFSNAMELEN]; 3168 int32_t vfc_typenum; 3169 int32_t vfc_refcount; 3170 int32_t vfc_flags; 3171 uint32_t vfc_next; 3172 }; 3173 3174 static int 3175 vfsconf2x32(struct sysctl_req *req, struct vfsconf *vfsp) 3176 { 3177 struct xvfsconf32 xvfsp; 3178 3179 strcpy(xvfsp.vfc_name, vfsp->vfc_name); 3180 xvfsp.vfc_typenum = vfsp->vfc_typenum; 3181 xvfsp.vfc_refcount = vfsp->vfc_refcount; 3182 xvfsp.vfc_flags = vfsp->vfc_flags; 3183 xvfsp.vfc_vfsops = 0; 3184 xvfsp.vfc_next = 0; 3185 return (SYSCTL_OUT(req, &xvfsp, sizeof(xvfsp))); 3186 } 3187 #endif 3188 3189 /* 3190 * Top level filesystem related information gathering. 3191 */ 3192 static int 3193 sysctl_vfs_conflist(SYSCTL_HANDLER_ARGS) 3194 { 3195 struct vfsconf *vfsp; 3196 int error; 3197 3198 error = 0; 3199 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) { 3200 #ifdef COMPAT_FREEBSD32 3201 if (req->flags & SCTL_MASK32) 3202 error = vfsconf2x32(req, vfsp); 3203 else 3204 #endif 3205 error = vfsconf2x(req, vfsp); 3206 if (error) 3207 break; 3208 } 3209 return (error); 3210 } 3211 3212 SYSCTL_PROC(_vfs, OID_AUTO, conflist, CTLTYPE_OPAQUE | CTLFLAG_RD, 3213 NULL, 0, sysctl_vfs_conflist, 3214 "S,xvfsconf", "List of all configured filesystems"); 3215 3216 #ifndef BURN_BRIDGES 3217 static int sysctl_ovfs_conf(SYSCTL_HANDLER_ARGS); 3218 3219 static int 3220 vfs_sysctl(SYSCTL_HANDLER_ARGS) 3221 { 3222 int *name = (int *)arg1 - 1; /* XXX */ 3223 u_int namelen = arg2 + 1; /* XXX */ 3224 struct vfsconf *vfsp; 3225 3226 log(LOG_WARNING, "userland calling deprecated sysctl, " 3227 "please rebuild world\n"); 3228 3229 #if 1 || defined(COMPAT_PRELITE2) 3230 /* Resolve ambiguity between VFS_VFSCONF and VFS_GENERIC. */ 3231 if (namelen == 1) 3232 return (sysctl_ovfs_conf(oidp, arg1, arg2, req)); 3233 #endif 3234 3235 switch (name[1]) { 3236 case VFS_MAXTYPENUM: 3237 if (namelen != 2) 3238 return (ENOTDIR); 3239 return (SYSCTL_OUT(req, &maxvfsconf, sizeof(int))); 3240 case VFS_CONF: 3241 if (namelen != 3) 3242 return (ENOTDIR); /* overloaded */ 3243 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) 3244 if (vfsp->vfc_typenum == name[2]) 3245 break; 3246 if (vfsp == NULL) 3247 return (EOPNOTSUPP); 3248 #ifdef COMPAT_FREEBSD32 3249 if (req->flags & SCTL_MASK32) 3250 return (vfsconf2x32(req, vfsp)); 3251 else 3252 #endif 3253 return (vfsconf2x(req, vfsp)); 3254 } 3255 return (EOPNOTSUPP); 3256 } 3257 3258 static SYSCTL_NODE(_vfs, VFS_GENERIC, generic, CTLFLAG_RD | CTLFLAG_SKIP, 3259 vfs_sysctl, "Generic filesystem"); 3260 3261 #if 1 || defined(COMPAT_PRELITE2) 3262 3263 static int 3264 sysctl_ovfs_conf(SYSCTL_HANDLER_ARGS) 3265 { 3266 int error; 3267 struct vfsconf *vfsp; 3268 struct ovfsconf ovfs; 3269 3270 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) { 3271 bzero(&ovfs, sizeof(ovfs)); 3272 ovfs.vfc_vfsops = vfsp->vfc_vfsops; /* XXX used as flag */ 3273 strcpy(ovfs.vfc_name, vfsp->vfc_name); 3274 ovfs.vfc_index = vfsp->vfc_typenum; 3275 ovfs.vfc_refcount = vfsp->vfc_refcount; 3276 ovfs.vfc_flags = vfsp->vfc_flags; 3277 error = SYSCTL_OUT(req, &ovfs, sizeof ovfs); 3278 if (error) 3279 return error; 3280 } 3281 return 0; 3282 } 3283 3284 #endif /* 1 || COMPAT_PRELITE2 */ 3285 #endif /* !BURN_BRIDGES */ 3286 3287 #define KINFO_VNODESLOP 10 3288 #ifdef notyet 3289 /* 3290 * Dump vnode list (via sysctl). 3291 */ 3292 /* ARGSUSED */ 3293 static int 3294 sysctl_vnode(SYSCTL_HANDLER_ARGS) 3295 { 3296 struct xvnode *xvn; 3297 struct mount *mp; 3298 struct vnode *vp; 3299 int error, len, n; 3300 3301 /* 3302 * Stale numvnodes access is not fatal here. 3303 */ 3304 req->lock = 0; 3305 len = (numvnodes + KINFO_VNODESLOP) * sizeof *xvn; 3306 if (!req->oldptr) 3307 /* Make an estimate */ 3308 return (SYSCTL_OUT(req, 0, len)); 3309 3310 error = sysctl_wire_old_buffer(req, 0); 3311 if (error != 0) 3312 return (error); 3313 xvn = malloc(len, M_TEMP, M_ZERO | M_WAITOK); 3314 n = 0; 3315 mtx_lock(&mountlist_mtx); 3316 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 3317 if (vfs_busy(mp, MBF_NOWAIT | MBF_MNTLSTLOCK)) 3318 continue; 3319 MNT_ILOCK(mp); 3320 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) { 3321 if (n == len) 3322 break; 3323 vref(vp); 3324 xvn[n].xv_size = sizeof *xvn; 3325 xvn[n].xv_vnode = vp; 3326 xvn[n].xv_id = 0; /* XXX compat */ 3327 #define XV_COPY(field) xvn[n].xv_##field = vp->v_##field 3328 XV_COPY(usecount); 3329 XV_COPY(writecount); 3330 XV_COPY(holdcnt); 3331 XV_COPY(mount); 3332 XV_COPY(numoutput); 3333 XV_COPY(type); 3334 #undef XV_COPY 3335 xvn[n].xv_flag = vp->v_vflag; 3336 3337 switch (vp->v_type) { 3338 case VREG: 3339 case VDIR: 3340 case VLNK: 3341 break; 3342 case VBLK: 3343 case VCHR: 3344 if (vp->v_rdev == NULL) { 3345 vrele(vp); 3346 continue; 3347 } 3348 xvn[n].xv_dev = dev2udev(vp->v_rdev); 3349 break; 3350 case VSOCK: 3351 xvn[n].xv_socket = vp->v_socket; 3352 break; 3353 case VFIFO: 3354 xvn[n].xv_fifo = vp->v_fifoinfo; 3355 break; 3356 case VNON: 3357 case VBAD: 3358 default: 3359 /* shouldn't happen? */ 3360 vrele(vp); 3361 continue; 3362 } 3363 vrele(vp); 3364 ++n; 3365 } 3366 MNT_IUNLOCK(mp); 3367 mtx_lock(&mountlist_mtx); 3368 vfs_unbusy(mp); 3369 if (n == len) 3370 break; 3371 } 3372 mtx_unlock(&mountlist_mtx); 3373 3374 error = SYSCTL_OUT(req, xvn, n * sizeof *xvn); 3375 free(xvn, M_TEMP); 3376 return (error); 3377 } 3378 3379 SYSCTL_PROC(_kern, KERN_VNODE, vnode, CTLTYPE_OPAQUE|CTLFLAG_RD, 3380 0, 0, sysctl_vnode, "S,xvnode", ""); 3381 #endif 3382 3383 /* 3384 * Unmount all filesystems. The list is traversed in reverse order 3385 * of mounting to avoid dependencies. 3386 */ 3387 void 3388 vfs_unmountall(void) 3389 { 3390 struct mount *mp; 3391 struct thread *td; 3392 int error; 3393 3394 CTR1(KTR_VFS, "%s: unmounting all filesystems", __func__); 3395 td = curthread; 3396 3397 /* 3398 * Since this only runs when rebooting, it is not interlocked. 3399 */ 3400 while(!TAILQ_EMPTY(&mountlist)) { 3401 mp = TAILQ_LAST(&mountlist, mntlist); 3402 error = dounmount(mp, MNT_FORCE, td); 3403 if (error) { 3404 TAILQ_REMOVE(&mountlist, mp, mnt_list); 3405 /* 3406 * XXX: Due to the way in which we mount the root 3407 * file system off of devfs, devfs will generate a 3408 * "busy" warning when we try to unmount it before 3409 * the root. Don't print a warning as a result in 3410 * order to avoid false positive errors that may 3411 * cause needless upset. 3412 */ 3413 if (strcmp(mp->mnt_vfc->vfc_name, "devfs") != 0) { 3414 printf("unmount of %s failed (", 3415 mp->mnt_stat.f_mntonname); 3416 if (error == EBUSY) 3417 printf("BUSY)\n"); 3418 else 3419 printf("%d)\n", error); 3420 } 3421 } else { 3422 /* The unmount has removed mp from the mountlist */ 3423 } 3424 } 3425 } 3426 3427 /* 3428 * perform msync on all vnodes under a mount point 3429 * the mount point must be locked. 3430 */ 3431 void 3432 vfs_msync(struct mount *mp, int flags) 3433 { 3434 struct vnode *vp, *mvp; 3435 struct vm_object *obj; 3436 3437 CTR2(KTR_VFS, "%s: mp %p", __func__, mp); 3438 MNT_VNODE_FOREACH_ACTIVE(vp, mp, mvp) { 3439 obj = vp->v_object; 3440 if (obj != NULL && (obj->flags & OBJ_MIGHTBEDIRTY) != 0 && 3441 (flags == MNT_WAIT || VOP_ISLOCKED(vp) == 0)) { 3442 if (!vget(vp, 3443 LK_EXCLUSIVE | LK_RETRY | LK_INTERLOCK, 3444 curthread)) { 3445 if (vp->v_vflag & VV_NOSYNC) { /* unlinked */ 3446 vput(vp); 3447 continue; 3448 } 3449 3450 obj = vp->v_object; 3451 if (obj != NULL) { 3452 VM_OBJECT_WLOCK(obj); 3453 vm_object_page_clean(obj, 0, 0, 3454 flags == MNT_WAIT ? 3455 OBJPC_SYNC : OBJPC_NOSYNC); 3456 VM_OBJECT_WUNLOCK(obj); 3457 } 3458 vput(vp); 3459 } 3460 } else 3461 VI_UNLOCK(vp); 3462 } 3463 } 3464 3465 static void 3466 destroy_vpollinfo(struct vpollinfo *vi) 3467 { 3468 seldrain(&vi->vpi_selinfo); 3469 knlist_destroy(&vi->vpi_selinfo.si_note); 3470 mtx_destroy(&vi->vpi_lock); 3471 uma_zfree(vnodepoll_zone, vi); 3472 } 3473 3474 /* 3475 * Initalize per-vnode helper structure to hold poll-related state. 3476 */ 3477 void 3478 v_addpollinfo(struct vnode *vp) 3479 { 3480 struct vpollinfo *vi; 3481 3482 if (vp->v_pollinfo != NULL) 3483 return; 3484 vi = uma_zalloc(vnodepoll_zone, M_WAITOK); 3485 mtx_init(&vi->vpi_lock, "vnode pollinfo", NULL, MTX_DEF); 3486 knlist_init(&vi->vpi_selinfo.si_note, vp, vfs_knllock, 3487 vfs_knlunlock, vfs_knl_assert_locked, vfs_knl_assert_unlocked); 3488 VI_LOCK(vp); 3489 if (vp->v_pollinfo != NULL) { 3490 VI_UNLOCK(vp); 3491 destroy_vpollinfo(vi); 3492 return; 3493 } 3494 vp->v_pollinfo = vi; 3495 VI_UNLOCK(vp); 3496 } 3497 3498 /* 3499 * Record a process's interest in events which might happen to 3500 * a vnode. Because poll uses the historic select-style interface 3501 * internally, this routine serves as both the ``check for any 3502 * pending events'' and the ``record my interest in future events'' 3503 * functions. (These are done together, while the lock is held, 3504 * to avoid race conditions.) 3505 */ 3506 int 3507 vn_pollrecord(struct vnode *vp, struct thread *td, int events) 3508 { 3509 3510 v_addpollinfo(vp); 3511 mtx_lock(&vp->v_pollinfo->vpi_lock); 3512 if (vp->v_pollinfo->vpi_revents & events) { 3513 /* 3514 * This leaves events we are not interested 3515 * in available for the other process which 3516 * which presumably had requested them 3517 * (otherwise they would never have been 3518 * recorded). 3519 */ 3520 events &= vp->v_pollinfo->vpi_revents; 3521 vp->v_pollinfo->vpi_revents &= ~events; 3522 3523 mtx_unlock(&vp->v_pollinfo->vpi_lock); 3524 return (events); 3525 } 3526 vp->v_pollinfo->vpi_events |= events; 3527 selrecord(td, &vp->v_pollinfo->vpi_selinfo); 3528 mtx_unlock(&vp->v_pollinfo->vpi_lock); 3529 return (0); 3530 } 3531 3532 /* 3533 * Routine to create and manage a filesystem syncer vnode. 3534 */ 3535 #define sync_close ((int (*)(struct vop_close_args *))nullop) 3536 static int sync_fsync(struct vop_fsync_args *); 3537 static int sync_inactive(struct vop_inactive_args *); 3538 static int sync_reclaim(struct vop_reclaim_args *); 3539 3540 static struct vop_vector sync_vnodeops = { 3541 .vop_bypass = VOP_EOPNOTSUPP, 3542 .vop_close = sync_close, /* close */ 3543 .vop_fsync = sync_fsync, /* fsync */ 3544 .vop_inactive = sync_inactive, /* inactive */ 3545 .vop_reclaim = sync_reclaim, /* reclaim */ 3546 .vop_lock1 = vop_stdlock, /* lock */ 3547 .vop_unlock = vop_stdunlock, /* unlock */ 3548 .vop_islocked = vop_stdislocked, /* islocked */ 3549 }; 3550 3551 /* 3552 * Create a new filesystem syncer vnode for the specified mount point. 3553 */ 3554 void 3555 vfs_allocate_syncvnode(struct mount *mp) 3556 { 3557 struct vnode *vp; 3558 struct bufobj *bo; 3559 static long start, incr, next; 3560 int error; 3561 3562 /* Allocate a new vnode */ 3563 error = getnewvnode("syncer", mp, &sync_vnodeops, &vp); 3564 if (error != 0) 3565 panic("vfs_allocate_syncvnode: getnewvnode() failed"); 3566 vp->v_type = VNON; 3567 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 3568 vp->v_vflag |= VV_FORCEINSMQ; 3569 error = insmntque(vp, mp); 3570 if (error != 0) 3571 panic("vfs_allocate_syncvnode: insmntque() failed"); 3572 vp->v_vflag &= ~VV_FORCEINSMQ; 3573 VOP_UNLOCK(vp, 0); 3574 /* 3575 * Place the vnode onto the syncer worklist. We attempt to 3576 * scatter them about on the list so that they will go off 3577 * at evenly distributed times even if all the filesystems 3578 * are mounted at once. 3579 */ 3580 next += incr; 3581 if (next == 0 || next > syncer_maxdelay) { 3582 start /= 2; 3583 incr /= 2; 3584 if (start == 0) { 3585 start = syncer_maxdelay / 2; 3586 incr = syncer_maxdelay; 3587 } 3588 next = start; 3589 } 3590 bo = &vp->v_bufobj; 3591 BO_LOCK(bo); 3592 vn_syncer_add_to_worklist(bo, syncdelay > 0 ? next % syncdelay : 0); 3593 /* XXX - vn_syncer_add_to_worklist() also grabs and drops sync_mtx. */ 3594 mtx_lock(&sync_mtx); 3595 sync_vnode_count++; 3596 if (mp->mnt_syncer == NULL) { 3597 mp->mnt_syncer = vp; 3598 vp = NULL; 3599 } 3600 mtx_unlock(&sync_mtx); 3601 BO_UNLOCK(bo); 3602 if (vp != NULL) { 3603 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 3604 vgone(vp); 3605 vput(vp); 3606 } 3607 } 3608 3609 void 3610 vfs_deallocate_syncvnode(struct mount *mp) 3611 { 3612 struct vnode *vp; 3613 3614 mtx_lock(&sync_mtx); 3615 vp = mp->mnt_syncer; 3616 if (vp != NULL) 3617 mp->mnt_syncer = NULL; 3618 mtx_unlock(&sync_mtx); 3619 if (vp != NULL) 3620 vrele(vp); 3621 } 3622 3623 /* 3624 * Do a lazy sync of the filesystem. 3625 */ 3626 static int 3627 sync_fsync(struct vop_fsync_args *ap) 3628 { 3629 struct vnode *syncvp = ap->a_vp; 3630 struct mount *mp = syncvp->v_mount; 3631 int error, save; 3632 struct bufobj *bo; 3633 3634 /* 3635 * We only need to do something if this is a lazy evaluation. 3636 */ 3637 if (ap->a_waitfor != MNT_LAZY) 3638 return (0); 3639 3640 /* 3641 * Move ourselves to the back of the sync list. 3642 */ 3643 bo = &syncvp->v_bufobj; 3644 BO_LOCK(bo); 3645 vn_syncer_add_to_worklist(bo, syncdelay); 3646 BO_UNLOCK(bo); 3647 3648 /* 3649 * Walk the list of vnodes pushing all that are dirty and 3650 * not already on the sync list. 3651 */ 3652 mtx_lock(&mountlist_mtx); 3653 if (vfs_busy(mp, MBF_NOWAIT | MBF_MNTLSTLOCK) != 0) { 3654 mtx_unlock(&mountlist_mtx); 3655 return (0); 3656 } 3657 if (vn_start_write(NULL, &mp, V_NOWAIT) != 0) { 3658 vfs_unbusy(mp); 3659 return (0); 3660 } 3661 save = curthread_pflags_set(TDP_SYNCIO); 3662 vfs_msync(mp, MNT_NOWAIT); 3663 error = VFS_SYNC(mp, MNT_LAZY); 3664 curthread_pflags_restore(save); 3665 vn_finished_write(mp); 3666 vfs_unbusy(mp); 3667 return (error); 3668 } 3669 3670 /* 3671 * The syncer vnode is no referenced. 3672 */ 3673 static int 3674 sync_inactive(struct vop_inactive_args *ap) 3675 { 3676 3677 vgone(ap->a_vp); 3678 return (0); 3679 } 3680 3681 /* 3682 * The syncer vnode is no longer needed and is being decommissioned. 3683 * 3684 * Modifications to the worklist must be protected by sync_mtx. 3685 */ 3686 static int 3687 sync_reclaim(struct vop_reclaim_args *ap) 3688 { 3689 struct vnode *vp = ap->a_vp; 3690 struct bufobj *bo; 3691 3692 bo = &vp->v_bufobj; 3693 BO_LOCK(bo); 3694 mtx_lock(&sync_mtx); 3695 if (vp->v_mount->mnt_syncer == vp) 3696 vp->v_mount->mnt_syncer = NULL; 3697 if (bo->bo_flag & BO_ONWORKLST) { 3698 LIST_REMOVE(bo, bo_synclist); 3699 syncer_worklist_len--; 3700 sync_vnode_count--; 3701 bo->bo_flag &= ~BO_ONWORKLST; 3702 } 3703 mtx_unlock(&sync_mtx); 3704 BO_UNLOCK(bo); 3705 3706 return (0); 3707 } 3708 3709 /* 3710 * Check if vnode represents a disk device 3711 */ 3712 int 3713 vn_isdisk(struct vnode *vp, int *errp) 3714 { 3715 int error; 3716 3717 error = 0; 3718 dev_lock(); 3719 if (vp->v_type != VCHR) 3720 error = ENOTBLK; 3721 else if (vp->v_rdev == NULL) 3722 error = ENXIO; 3723 else if (vp->v_rdev->si_devsw == NULL) 3724 error = ENXIO; 3725 else if (!(vp->v_rdev->si_devsw->d_flags & D_DISK)) 3726 error = ENOTBLK; 3727 dev_unlock(); 3728 if (errp != NULL) 3729 *errp = error; 3730 return (error == 0); 3731 } 3732 3733 /* 3734 * Common filesystem object access control check routine. Accepts a 3735 * vnode's type, "mode", uid and gid, requested access mode, credentials, 3736 * and optional call-by-reference privused argument allowing vaccess() 3737 * to indicate to the caller whether privilege was used to satisfy the 3738 * request (obsoleted). Returns 0 on success, or an errno on failure. 3739 */ 3740 int 3741 vaccess(enum vtype type, mode_t file_mode, uid_t file_uid, gid_t file_gid, 3742 accmode_t accmode, struct ucred *cred, int *privused) 3743 { 3744 accmode_t dac_granted; 3745 accmode_t priv_granted; 3746 3747 KASSERT((accmode & ~(VEXEC | VWRITE | VREAD | VADMIN | VAPPEND)) == 0, 3748 ("invalid bit in accmode")); 3749 KASSERT((accmode & VAPPEND) == 0 || (accmode & VWRITE), 3750 ("VAPPEND without VWRITE")); 3751 3752 /* 3753 * Look for a normal, non-privileged way to access the file/directory 3754 * as requested. If it exists, go with that. 3755 */ 3756 3757 if (privused != NULL) 3758 *privused = 0; 3759 3760 dac_granted = 0; 3761 3762 /* Check the owner. */ 3763 if (cred->cr_uid == file_uid) { 3764 dac_granted |= VADMIN; 3765 if (file_mode & S_IXUSR) 3766 dac_granted |= VEXEC; 3767 if (file_mode & S_IRUSR) 3768 dac_granted |= VREAD; 3769 if (file_mode & S_IWUSR) 3770 dac_granted |= (VWRITE | VAPPEND); 3771 3772 if ((accmode & dac_granted) == accmode) 3773 return (0); 3774 3775 goto privcheck; 3776 } 3777 3778 /* Otherwise, check the groups (first match) */ 3779 if (groupmember(file_gid, cred)) { 3780 if (file_mode & S_IXGRP) 3781 dac_granted |= VEXEC; 3782 if (file_mode & S_IRGRP) 3783 dac_granted |= VREAD; 3784 if (file_mode & S_IWGRP) 3785 dac_granted |= (VWRITE | VAPPEND); 3786 3787 if ((accmode & dac_granted) == accmode) 3788 return (0); 3789 3790 goto privcheck; 3791 } 3792 3793 /* Otherwise, check everyone else. */ 3794 if (file_mode & S_IXOTH) 3795 dac_granted |= VEXEC; 3796 if (file_mode & S_IROTH) 3797 dac_granted |= VREAD; 3798 if (file_mode & S_IWOTH) 3799 dac_granted |= (VWRITE | VAPPEND); 3800 if ((accmode & dac_granted) == accmode) 3801 return (0); 3802 3803 privcheck: 3804 /* 3805 * Build a privilege mask to determine if the set of privileges 3806 * satisfies the requirements when combined with the granted mask 3807 * from above. For each privilege, if the privilege is required, 3808 * bitwise or the request type onto the priv_granted mask. 3809 */ 3810 priv_granted = 0; 3811 3812 if (type == VDIR) { 3813 /* 3814 * For directories, use PRIV_VFS_LOOKUP to satisfy VEXEC 3815 * requests, instead of PRIV_VFS_EXEC. 3816 */ 3817 if ((accmode & VEXEC) && ((dac_granted & VEXEC) == 0) && 3818 !priv_check_cred(cred, PRIV_VFS_LOOKUP, 0)) 3819 priv_granted |= VEXEC; 3820 } else { 3821 /* 3822 * Ensure that at least one execute bit is on. Otherwise, 3823 * a privileged user will always succeed, and we don't want 3824 * this to happen unless the file really is executable. 3825 */ 3826 if ((accmode & VEXEC) && ((dac_granted & VEXEC) == 0) && 3827 (file_mode & (S_IXUSR | S_IXGRP | S_IXOTH)) != 0 && 3828 !priv_check_cred(cred, PRIV_VFS_EXEC, 0)) 3829 priv_granted |= VEXEC; 3830 } 3831 3832 if ((accmode & VREAD) && ((dac_granted & VREAD) == 0) && 3833 !priv_check_cred(cred, PRIV_VFS_READ, 0)) 3834 priv_granted |= VREAD; 3835 3836 if ((accmode & VWRITE) && ((dac_granted & VWRITE) == 0) && 3837 !priv_check_cred(cred, PRIV_VFS_WRITE, 0)) 3838 priv_granted |= (VWRITE | VAPPEND); 3839 3840 if ((accmode & VADMIN) && ((dac_granted & VADMIN) == 0) && 3841 !priv_check_cred(cred, PRIV_VFS_ADMIN, 0)) 3842 priv_granted |= VADMIN; 3843 3844 if ((accmode & (priv_granted | dac_granted)) == accmode) { 3845 /* XXX audit: privilege used */ 3846 if (privused != NULL) 3847 *privused = 1; 3848 return (0); 3849 } 3850 3851 return ((accmode & VADMIN) ? EPERM : EACCES); 3852 } 3853 3854 /* 3855 * Credential check based on process requesting service, and per-attribute 3856 * permissions. 3857 */ 3858 int 3859 extattr_check_cred(struct vnode *vp, int attrnamespace, struct ucred *cred, 3860 struct thread *td, accmode_t accmode) 3861 { 3862 3863 /* 3864 * Kernel-invoked always succeeds. 3865 */ 3866 if (cred == NOCRED) 3867 return (0); 3868 3869 /* 3870 * Do not allow privileged processes in jail to directly manipulate 3871 * system attributes. 3872 */ 3873 switch (attrnamespace) { 3874 case EXTATTR_NAMESPACE_SYSTEM: 3875 /* Potentially should be: return (EPERM); */ 3876 return (priv_check_cred(cred, PRIV_VFS_EXTATTR_SYSTEM, 0)); 3877 case EXTATTR_NAMESPACE_USER: 3878 return (VOP_ACCESS(vp, accmode, cred, td)); 3879 default: 3880 return (EPERM); 3881 } 3882 } 3883 3884 #ifdef DEBUG_VFS_LOCKS 3885 /* 3886 * This only exists to supress warnings from unlocked specfs accesses. It is 3887 * no longer ok to have an unlocked VFS. 3888 */ 3889 #define IGNORE_LOCK(vp) (panicstr != NULL || (vp) == NULL || \ 3890 (vp)->v_type == VCHR || (vp)->v_type == VBAD) 3891 3892 int vfs_badlock_ddb = 1; /* Drop into debugger on violation. */ 3893 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_ddb, CTLFLAG_RW, &vfs_badlock_ddb, 0, 3894 "Drop into debugger on lock violation"); 3895 3896 int vfs_badlock_mutex = 1; /* Check for interlock across VOPs. */ 3897 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_mutex, CTLFLAG_RW, &vfs_badlock_mutex, 3898 0, "Check for interlock across VOPs"); 3899 3900 int vfs_badlock_print = 1; /* Print lock violations. */ 3901 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_print, CTLFLAG_RW, &vfs_badlock_print, 3902 0, "Print lock violations"); 3903 3904 #ifdef KDB 3905 int vfs_badlock_backtrace = 1; /* Print backtrace at lock violations. */ 3906 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_backtrace, CTLFLAG_RW, 3907 &vfs_badlock_backtrace, 0, "Print backtrace at lock violations"); 3908 #endif 3909 3910 static void 3911 vfs_badlock(const char *msg, const char *str, struct vnode *vp) 3912 { 3913 3914 #ifdef KDB 3915 if (vfs_badlock_backtrace) 3916 kdb_backtrace(); 3917 #endif 3918 if (vfs_badlock_print) 3919 printf("%s: %p %s\n", str, (void *)vp, msg); 3920 if (vfs_badlock_ddb) 3921 kdb_enter(KDB_WHY_VFSLOCK, "lock violation"); 3922 } 3923 3924 void 3925 assert_vi_locked(struct vnode *vp, const char *str) 3926 { 3927 3928 if (vfs_badlock_mutex && !mtx_owned(VI_MTX(vp))) 3929 vfs_badlock("interlock is not locked but should be", str, vp); 3930 } 3931 3932 void 3933 assert_vi_unlocked(struct vnode *vp, const char *str) 3934 { 3935 3936 if (vfs_badlock_mutex && mtx_owned(VI_MTX(vp))) 3937 vfs_badlock("interlock is locked but should not be", str, vp); 3938 } 3939 3940 void 3941 assert_vop_locked(struct vnode *vp, const char *str) 3942 { 3943 int locked; 3944 3945 if (!IGNORE_LOCK(vp)) { 3946 locked = VOP_ISLOCKED(vp); 3947 if (locked == 0 || locked == LK_EXCLOTHER) 3948 vfs_badlock("is not locked but should be", str, vp); 3949 } 3950 } 3951 3952 void 3953 assert_vop_unlocked(struct vnode *vp, const char *str) 3954 { 3955 3956 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) == LK_EXCLUSIVE) 3957 vfs_badlock("is locked but should not be", str, vp); 3958 } 3959 3960 void 3961 assert_vop_elocked(struct vnode *vp, const char *str) 3962 { 3963 3964 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) != LK_EXCLUSIVE) 3965 vfs_badlock("is not exclusive locked but should be", str, vp); 3966 } 3967 3968 #if 0 3969 void 3970 assert_vop_elocked_other(struct vnode *vp, const char *str) 3971 { 3972 3973 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) != LK_EXCLOTHER) 3974 vfs_badlock("is not exclusive locked by another thread", 3975 str, vp); 3976 } 3977 3978 void 3979 assert_vop_slocked(struct vnode *vp, const char *str) 3980 { 3981 3982 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) != LK_SHARED) 3983 vfs_badlock("is not locked shared but should be", str, vp); 3984 } 3985 #endif /* 0 */ 3986 #endif /* DEBUG_VFS_LOCKS */ 3987 3988 void 3989 vop_rename_fail(struct vop_rename_args *ap) 3990 { 3991 3992 if (ap->a_tvp != NULL) 3993 vput(ap->a_tvp); 3994 if (ap->a_tdvp == ap->a_tvp) 3995 vrele(ap->a_tdvp); 3996 else 3997 vput(ap->a_tdvp); 3998 vrele(ap->a_fdvp); 3999 vrele(ap->a_fvp); 4000 } 4001 4002 void 4003 vop_rename_pre(void *ap) 4004 { 4005 struct vop_rename_args *a = ap; 4006 4007 #ifdef DEBUG_VFS_LOCKS 4008 if (a->a_tvp) 4009 ASSERT_VI_UNLOCKED(a->a_tvp, "VOP_RENAME"); 4010 ASSERT_VI_UNLOCKED(a->a_tdvp, "VOP_RENAME"); 4011 ASSERT_VI_UNLOCKED(a->a_fvp, "VOP_RENAME"); 4012 ASSERT_VI_UNLOCKED(a->a_fdvp, "VOP_RENAME"); 4013 4014 /* Check the source (from). */ 4015 if (a->a_tdvp->v_vnlock != a->a_fdvp->v_vnlock && 4016 (a->a_tvp == NULL || a->a_tvp->v_vnlock != a->a_fdvp->v_vnlock)) 4017 ASSERT_VOP_UNLOCKED(a->a_fdvp, "vop_rename: fdvp locked"); 4018 if (a->a_tvp == NULL || a->a_tvp->v_vnlock != a->a_fvp->v_vnlock) 4019 ASSERT_VOP_UNLOCKED(a->a_fvp, "vop_rename: fvp locked"); 4020 4021 /* Check the target. */ 4022 if (a->a_tvp) 4023 ASSERT_VOP_LOCKED(a->a_tvp, "vop_rename: tvp not locked"); 4024 ASSERT_VOP_LOCKED(a->a_tdvp, "vop_rename: tdvp not locked"); 4025 #endif 4026 if (a->a_tdvp != a->a_fdvp) 4027 vhold(a->a_fdvp); 4028 if (a->a_tvp != a->a_fvp) 4029 vhold(a->a_fvp); 4030 vhold(a->a_tdvp); 4031 if (a->a_tvp) 4032 vhold(a->a_tvp); 4033 } 4034 4035 void 4036 vop_strategy_pre(void *ap) 4037 { 4038 #ifdef DEBUG_VFS_LOCKS 4039 struct vop_strategy_args *a; 4040 struct buf *bp; 4041 4042 a = ap; 4043 bp = a->a_bp; 4044 4045 /* 4046 * Cluster ops lock their component buffers but not the IO container. 4047 */ 4048 if ((bp->b_flags & B_CLUSTER) != 0) 4049 return; 4050 4051 if (panicstr == NULL && !BUF_ISLOCKED(bp)) { 4052 if (vfs_badlock_print) 4053 printf( 4054 "VOP_STRATEGY: bp is not locked but should be\n"); 4055 if (vfs_badlock_ddb) 4056 kdb_enter(KDB_WHY_VFSLOCK, "lock violation"); 4057 } 4058 #endif 4059 } 4060 4061 void 4062 vop_lock_pre(void *ap) 4063 { 4064 #ifdef DEBUG_VFS_LOCKS 4065 struct vop_lock1_args *a = ap; 4066 4067 if ((a->a_flags & LK_INTERLOCK) == 0) 4068 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_LOCK"); 4069 else 4070 ASSERT_VI_LOCKED(a->a_vp, "VOP_LOCK"); 4071 #endif 4072 } 4073 4074 void 4075 vop_lock_post(void *ap, int rc) 4076 { 4077 #ifdef DEBUG_VFS_LOCKS 4078 struct vop_lock1_args *a = ap; 4079 4080 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_LOCK"); 4081 if (rc == 0 && (a->a_flags & LK_EXCLOTHER) == 0) 4082 ASSERT_VOP_LOCKED(a->a_vp, "VOP_LOCK"); 4083 #endif 4084 } 4085 4086 void 4087 vop_unlock_pre(void *ap) 4088 { 4089 #ifdef DEBUG_VFS_LOCKS 4090 struct vop_unlock_args *a = ap; 4091 4092 if (a->a_flags & LK_INTERLOCK) 4093 ASSERT_VI_LOCKED(a->a_vp, "VOP_UNLOCK"); 4094 ASSERT_VOP_LOCKED(a->a_vp, "VOP_UNLOCK"); 4095 #endif 4096 } 4097 4098 void 4099 vop_unlock_post(void *ap, int rc) 4100 { 4101 #ifdef DEBUG_VFS_LOCKS 4102 struct vop_unlock_args *a = ap; 4103 4104 if (a->a_flags & LK_INTERLOCK) 4105 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_UNLOCK"); 4106 #endif 4107 } 4108 4109 void 4110 vop_create_post(void *ap, int rc) 4111 { 4112 struct vop_create_args *a = ap; 4113 4114 if (!rc) 4115 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 4116 } 4117 4118 void 4119 vop_deleteextattr_post(void *ap, int rc) 4120 { 4121 struct vop_deleteextattr_args *a = ap; 4122 4123 if (!rc) 4124 VFS_KNOTE_LOCKED(a->a_vp, NOTE_ATTRIB); 4125 } 4126 4127 void 4128 vop_link_post(void *ap, int rc) 4129 { 4130 struct vop_link_args *a = ap; 4131 4132 if (!rc) { 4133 VFS_KNOTE_LOCKED(a->a_vp, NOTE_LINK); 4134 VFS_KNOTE_LOCKED(a->a_tdvp, NOTE_WRITE); 4135 } 4136 } 4137 4138 void 4139 vop_mkdir_post(void *ap, int rc) 4140 { 4141 struct vop_mkdir_args *a = ap; 4142 4143 if (!rc) 4144 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE | NOTE_LINK); 4145 } 4146 4147 void 4148 vop_mknod_post(void *ap, int rc) 4149 { 4150 struct vop_mknod_args *a = ap; 4151 4152 if (!rc) 4153 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 4154 } 4155 4156 void 4157 vop_remove_post(void *ap, int rc) 4158 { 4159 struct vop_remove_args *a = ap; 4160 4161 if (!rc) { 4162 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 4163 VFS_KNOTE_LOCKED(a->a_vp, NOTE_DELETE); 4164 } 4165 } 4166 4167 void 4168 vop_rename_post(void *ap, int rc) 4169 { 4170 struct vop_rename_args *a = ap; 4171 4172 if (!rc) { 4173 VFS_KNOTE_UNLOCKED(a->a_fdvp, NOTE_WRITE); 4174 VFS_KNOTE_UNLOCKED(a->a_tdvp, NOTE_WRITE); 4175 VFS_KNOTE_UNLOCKED(a->a_fvp, NOTE_RENAME); 4176 if (a->a_tvp) 4177 VFS_KNOTE_UNLOCKED(a->a_tvp, NOTE_DELETE); 4178 } 4179 if (a->a_tdvp != a->a_fdvp) 4180 vdrop(a->a_fdvp); 4181 if (a->a_tvp != a->a_fvp) 4182 vdrop(a->a_fvp); 4183 vdrop(a->a_tdvp); 4184 if (a->a_tvp) 4185 vdrop(a->a_tvp); 4186 } 4187 4188 void 4189 vop_rmdir_post(void *ap, int rc) 4190 { 4191 struct vop_rmdir_args *a = ap; 4192 4193 if (!rc) { 4194 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE | NOTE_LINK); 4195 VFS_KNOTE_LOCKED(a->a_vp, NOTE_DELETE); 4196 } 4197 } 4198 4199 void 4200 vop_setattr_post(void *ap, int rc) 4201 { 4202 struct vop_setattr_args *a = ap; 4203 4204 if (!rc) 4205 VFS_KNOTE_LOCKED(a->a_vp, NOTE_ATTRIB); 4206 } 4207 4208 void 4209 vop_setextattr_post(void *ap, int rc) 4210 { 4211 struct vop_setextattr_args *a = ap; 4212 4213 if (!rc) 4214 VFS_KNOTE_LOCKED(a->a_vp, NOTE_ATTRIB); 4215 } 4216 4217 void 4218 vop_symlink_post(void *ap, int rc) 4219 { 4220 struct vop_symlink_args *a = ap; 4221 4222 if (!rc) 4223 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 4224 } 4225 4226 static struct knlist fs_knlist; 4227 4228 static void 4229 vfs_event_init(void *arg) 4230 { 4231 knlist_init_mtx(&fs_knlist, NULL); 4232 } 4233 /* XXX - correct order? */ 4234 SYSINIT(vfs_knlist, SI_SUB_VFS, SI_ORDER_ANY, vfs_event_init, NULL); 4235 4236 void 4237 vfs_event_signal(fsid_t *fsid, uint32_t event, intptr_t data __unused) 4238 { 4239 4240 KNOTE_UNLOCKED(&fs_knlist, event); 4241 } 4242 4243 static int filt_fsattach(struct knote *kn); 4244 static void filt_fsdetach(struct knote *kn); 4245 static int filt_fsevent(struct knote *kn, long hint); 4246 4247 struct filterops fs_filtops = { 4248 .f_isfd = 0, 4249 .f_attach = filt_fsattach, 4250 .f_detach = filt_fsdetach, 4251 .f_event = filt_fsevent 4252 }; 4253 4254 static int 4255 filt_fsattach(struct knote *kn) 4256 { 4257 4258 kn->kn_flags |= EV_CLEAR; 4259 knlist_add(&fs_knlist, kn, 0); 4260 return (0); 4261 } 4262 4263 static void 4264 filt_fsdetach(struct knote *kn) 4265 { 4266 4267 knlist_remove(&fs_knlist, kn, 0); 4268 } 4269 4270 static int 4271 filt_fsevent(struct knote *kn, long hint) 4272 { 4273 4274 kn->kn_fflags |= hint; 4275 return (kn->kn_fflags != 0); 4276 } 4277 4278 static int 4279 sysctl_vfs_ctl(SYSCTL_HANDLER_ARGS) 4280 { 4281 struct vfsidctl vc; 4282 int error; 4283 struct mount *mp; 4284 4285 error = SYSCTL_IN(req, &vc, sizeof(vc)); 4286 if (error) 4287 return (error); 4288 if (vc.vc_vers != VFS_CTL_VERS1) 4289 return (EINVAL); 4290 mp = vfs_getvfs(&vc.vc_fsid); 4291 if (mp == NULL) 4292 return (ENOENT); 4293 /* ensure that a specific sysctl goes to the right filesystem. */ 4294 if (strcmp(vc.vc_fstypename, "*") != 0 && 4295 strcmp(vc.vc_fstypename, mp->mnt_vfc->vfc_name) != 0) { 4296 vfs_rel(mp); 4297 return (EINVAL); 4298 } 4299 VCTLTOREQ(&vc, req); 4300 error = VFS_SYSCTL(mp, vc.vc_op, req); 4301 vfs_rel(mp); 4302 return (error); 4303 } 4304 4305 SYSCTL_PROC(_vfs, OID_AUTO, ctl, CTLTYPE_OPAQUE | CTLFLAG_WR, 4306 NULL, 0, sysctl_vfs_ctl, "", 4307 "Sysctl by fsid"); 4308 4309 /* 4310 * Function to initialize a va_filerev field sensibly. 4311 * XXX: Wouldn't a random number make a lot more sense ?? 4312 */ 4313 u_quad_t 4314 init_va_filerev(void) 4315 { 4316 struct bintime bt; 4317 4318 getbinuptime(&bt); 4319 return (((u_quad_t)bt.sec << 32LL) | (bt.frac >> 32LL)); 4320 } 4321 4322 static int filt_vfsread(struct knote *kn, long hint); 4323 static int filt_vfswrite(struct knote *kn, long hint); 4324 static int filt_vfsvnode(struct knote *kn, long hint); 4325 static void filt_vfsdetach(struct knote *kn); 4326 static struct filterops vfsread_filtops = { 4327 .f_isfd = 1, 4328 .f_detach = filt_vfsdetach, 4329 .f_event = filt_vfsread 4330 }; 4331 static struct filterops vfswrite_filtops = { 4332 .f_isfd = 1, 4333 .f_detach = filt_vfsdetach, 4334 .f_event = filt_vfswrite 4335 }; 4336 static struct filterops vfsvnode_filtops = { 4337 .f_isfd = 1, 4338 .f_detach = filt_vfsdetach, 4339 .f_event = filt_vfsvnode 4340 }; 4341 4342 static void 4343 vfs_knllock(void *arg) 4344 { 4345 struct vnode *vp = arg; 4346 4347 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 4348 } 4349 4350 static void 4351 vfs_knlunlock(void *arg) 4352 { 4353 struct vnode *vp = arg; 4354 4355 VOP_UNLOCK(vp, 0); 4356 } 4357 4358 static void 4359 vfs_knl_assert_locked(void *arg) 4360 { 4361 #ifdef DEBUG_VFS_LOCKS 4362 struct vnode *vp = arg; 4363 4364 ASSERT_VOP_LOCKED(vp, "vfs_knl_assert_locked"); 4365 #endif 4366 } 4367 4368 static void 4369 vfs_knl_assert_unlocked(void *arg) 4370 { 4371 #ifdef DEBUG_VFS_LOCKS 4372 struct vnode *vp = arg; 4373 4374 ASSERT_VOP_UNLOCKED(vp, "vfs_knl_assert_unlocked"); 4375 #endif 4376 } 4377 4378 int 4379 vfs_kqfilter(struct vop_kqfilter_args *ap) 4380 { 4381 struct vnode *vp = ap->a_vp; 4382 struct knote *kn = ap->a_kn; 4383 struct knlist *knl; 4384 4385 switch (kn->kn_filter) { 4386 case EVFILT_READ: 4387 kn->kn_fop = &vfsread_filtops; 4388 break; 4389 case EVFILT_WRITE: 4390 kn->kn_fop = &vfswrite_filtops; 4391 break; 4392 case EVFILT_VNODE: 4393 kn->kn_fop = &vfsvnode_filtops; 4394 break; 4395 default: 4396 return (EINVAL); 4397 } 4398 4399 kn->kn_hook = (caddr_t)vp; 4400 4401 v_addpollinfo(vp); 4402 if (vp->v_pollinfo == NULL) 4403 return (ENOMEM); 4404 knl = &vp->v_pollinfo->vpi_selinfo.si_note; 4405 knlist_add(knl, kn, 0); 4406 4407 return (0); 4408 } 4409 4410 /* 4411 * Detach knote from vnode 4412 */ 4413 static void 4414 filt_vfsdetach(struct knote *kn) 4415 { 4416 struct vnode *vp = (struct vnode *)kn->kn_hook; 4417 4418 KASSERT(vp->v_pollinfo != NULL, ("Missing v_pollinfo")); 4419 knlist_remove(&vp->v_pollinfo->vpi_selinfo.si_note, kn, 0); 4420 } 4421 4422 /*ARGSUSED*/ 4423 static int 4424 filt_vfsread(struct knote *kn, long hint) 4425 { 4426 struct vnode *vp = (struct vnode *)kn->kn_hook; 4427 struct vattr va; 4428 int res; 4429 4430 /* 4431 * filesystem is gone, so set the EOF flag and schedule 4432 * the knote for deletion. 4433 */ 4434 if (hint == NOTE_REVOKE) { 4435 VI_LOCK(vp); 4436 kn->kn_flags |= (EV_EOF | EV_ONESHOT); 4437 VI_UNLOCK(vp); 4438 return (1); 4439 } 4440 4441 if (VOP_GETATTR(vp, &va, curthread->td_ucred)) 4442 return (0); 4443 4444 VI_LOCK(vp); 4445 kn->kn_data = va.va_size - kn->kn_fp->f_offset; 4446 res = (kn->kn_data != 0); 4447 VI_UNLOCK(vp); 4448 return (res); 4449 } 4450 4451 /*ARGSUSED*/ 4452 static int 4453 filt_vfswrite(struct knote *kn, long hint) 4454 { 4455 struct vnode *vp = (struct vnode *)kn->kn_hook; 4456 4457 VI_LOCK(vp); 4458 4459 /* 4460 * filesystem is gone, so set the EOF flag and schedule 4461 * the knote for deletion. 4462 */ 4463 if (hint == NOTE_REVOKE) 4464 kn->kn_flags |= (EV_EOF | EV_ONESHOT); 4465 4466 kn->kn_data = 0; 4467 VI_UNLOCK(vp); 4468 return (1); 4469 } 4470 4471 static int 4472 filt_vfsvnode(struct knote *kn, long hint) 4473 { 4474 struct vnode *vp = (struct vnode *)kn->kn_hook; 4475 int res; 4476 4477 VI_LOCK(vp); 4478 if (kn->kn_sfflags & hint) 4479 kn->kn_fflags |= hint; 4480 if (hint == NOTE_REVOKE) { 4481 kn->kn_flags |= EV_EOF; 4482 VI_UNLOCK(vp); 4483 return (1); 4484 } 4485 res = (kn->kn_fflags != 0); 4486 VI_UNLOCK(vp); 4487 return (res); 4488 } 4489 4490 int 4491 vfs_read_dirent(struct vop_readdir_args *ap, struct dirent *dp, off_t off) 4492 { 4493 int error; 4494 4495 if (dp->d_reclen > ap->a_uio->uio_resid) 4496 return (ENAMETOOLONG); 4497 error = uiomove(dp, dp->d_reclen, ap->a_uio); 4498 if (error) { 4499 if (ap->a_ncookies != NULL) { 4500 if (ap->a_cookies != NULL) 4501 free(ap->a_cookies, M_TEMP); 4502 ap->a_cookies = NULL; 4503 *ap->a_ncookies = 0; 4504 } 4505 return (error); 4506 } 4507 if (ap->a_ncookies == NULL) 4508 return (0); 4509 4510 KASSERT(ap->a_cookies, 4511 ("NULL ap->a_cookies value with non-NULL ap->a_ncookies!")); 4512 4513 *ap->a_cookies = realloc(*ap->a_cookies, 4514 (*ap->a_ncookies + 1) * sizeof(u_long), M_TEMP, M_WAITOK | M_ZERO); 4515 (*ap->a_cookies)[*ap->a_ncookies] = off; 4516 return (0); 4517 } 4518 4519 /* 4520 * Mark for update the access time of the file if the filesystem 4521 * supports VOP_MARKATIME. This functionality is used by execve and 4522 * mmap, so we want to avoid the I/O implied by directly setting 4523 * va_atime for the sake of efficiency. 4524 */ 4525 void 4526 vfs_mark_atime(struct vnode *vp, struct ucred *cred) 4527 { 4528 struct mount *mp; 4529 4530 mp = vp->v_mount; 4531 ASSERT_VOP_LOCKED(vp, "vfs_mark_atime"); 4532 if (mp != NULL && (mp->mnt_flag & (MNT_NOATIME | MNT_RDONLY)) == 0) 4533 (void)VOP_MARKATIME(vp); 4534 } 4535 4536 /* 4537 * The purpose of this routine is to remove granularity from accmode_t, 4538 * reducing it into standard unix access bits - VEXEC, VREAD, VWRITE, 4539 * VADMIN and VAPPEND. 4540 * 4541 * If it returns 0, the caller is supposed to continue with the usual 4542 * access checks using 'accmode' as modified by this routine. If it 4543 * returns nonzero value, the caller is supposed to return that value 4544 * as errno. 4545 * 4546 * Note that after this routine runs, accmode may be zero. 4547 */ 4548 int 4549 vfs_unixify_accmode(accmode_t *accmode) 4550 { 4551 /* 4552 * There is no way to specify explicit "deny" rule using 4553 * file mode or POSIX.1e ACLs. 4554 */ 4555 if (*accmode & VEXPLICIT_DENY) { 4556 *accmode = 0; 4557 return (0); 4558 } 4559 4560 /* 4561 * None of these can be translated into usual access bits. 4562 * Also, the common case for NFSv4 ACLs is to not contain 4563 * either of these bits. Caller should check for VWRITE 4564 * on the containing directory instead. 4565 */ 4566 if (*accmode & (VDELETE_CHILD | VDELETE)) 4567 return (EPERM); 4568 4569 if (*accmode & VADMIN_PERMS) { 4570 *accmode &= ~VADMIN_PERMS; 4571 *accmode |= VADMIN; 4572 } 4573 4574 /* 4575 * There is no way to deny VREAD_ATTRIBUTES, VREAD_ACL 4576 * or VSYNCHRONIZE using file mode or POSIX.1e ACL. 4577 */ 4578 *accmode &= ~(VSTAT_PERMS | VSYNCHRONIZE); 4579 4580 return (0); 4581 } 4582 4583 /* 4584 * These are helper functions for filesystems to traverse all 4585 * their vnodes. See MNT_VNODE_FOREACH_ALL() in sys/mount.h. 4586 * 4587 * This interface replaces MNT_VNODE_FOREACH. 4588 */ 4589 4590 MALLOC_DEFINE(M_VNODE_MARKER, "vnodemarker", "vnode marker"); 4591 4592 struct vnode * 4593 __mnt_vnode_next_all(struct vnode **mvp, struct mount *mp) 4594 { 4595 struct vnode *vp; 4596 4597 if (should_yield()) 4598 kern_yield(PRI_USER); 4599 MNT_ILOCK(mp); 4600 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch")); 4601 vp = TAILQ_NEXT(*mvp, v_nmntvnodes); 4602 while (vp != NULL && (vp->v_type == VMARKER || 4603 (vp->v_iflag & VI_DOOMED) != 0)) 4604 vp = TAILQ_NEXT(vp, v_nmntvnodes); 4605 4606 /* Check if we are done */ 4607 if (vp == NULL) { 4608 __mnt_vnode_markerfree_all(mvp, mp); 4609 /* MNT_IUNLOCK(mp); -- done in above function */ 4610 mtx_assert(MNT_MTX(mp), MA_NOTOWNED); 4611 return (NULL); 4612 } 4613 TAILQ_REMOVE(&mp->mnt_nvnodelist, *mvp, v_nmntvnodes); 4614 TAILQ_INSERT_AFTER(&mp->mnt_nvnodelist, vp, *mvp, v_nmntvnodes); 4615 VI_LOCK(vp); 4616 MNT_IUNLOCK(mp); 4617 return (vp); 4618 } 4619 4620 struct vnode * 4621 __mnt_vnode_first_all(struct vnode **mvp, struct mount *mp) 4622 { 4623 struct vnode *vp; 4624 4625 *mvp = malloc(sizeof(struct vnode), M_VNODE_MARKER, M_WAITOK | M_ZERO); 4626 MNT_ILOCK(mp); 4627 MNT_REF(mp); 4628 (*mvp)->v_type = VMARKER; 4629 4630 vp = TAILQ_FIRST(&mp->mnt_nvnodelist); 4631 while (vp != NULL && (vp->v_type == VMARKER || 4632 (vp->v_iflag & VI_DOOMED) != 0)) 4633 vp = TAILQ_NEXT(vp, v_nmntvnodes); 4634 4635 /* Check if we are done */ 4636 if (vp == NULL) { 4637 MNT_REL(mp); 4638 MNT_IUNLOCK(mp); 4639 free(*mvp, M_VNODE_MARKER); 4640 *mvp = NULL; 4641 return (NULL); 4642 } 4643 (*mvp)->v_mount = mp; 4644 TAILQ_INSERT_AFTER(&mp->mnt_nvnodelist, vp, *mvp, v_nmntvnodes); 4645 VI_LOCK(vp); 4646 MNT_IUNLOCK(mp); 4647 return (vp); 4648 } 4649 4650 4651 void 4652 __mnt_vnode_markerfree_all(struct vnode **mvp, struct mount *mp) 4653 { 4654 4655 if (*mvp == NULL) { 4656 MNT_IUNLOCK(mp); 4657 return; 4658 } 4659 4660 mtx_assert(MNT_MTX(mp), MA_OWNED); 4661 4662 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch")); 4663 TAILQ_REMOVE(&mp->mnt_nvnodelist, *mvp, v_nmntvnodes); 4664 MNT_REL(mp); 4665 MNT_IUNLOCK(mp); 4666 free(*mvp, M_VNODE_MARKER); 4667 *mvp = NULL; 4668 } 4669 4670 /* 4671 * These are helper functions for filesystems to traverse their 4672 * active vnodes. See MNT_VNODE_FOREACH_ACTIVE() in sys/mount.h 4673 */ 4674 static void 4675 mnt_vnode_markerfree_active(struct vnode **mvp, struct mount *mp) 4676 { 4677 4678 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch")); 4679 4680 MNT_ILOCK(mp); 4681 MNT_REL(mp); 4682 MNT_IUNLOCK(mp); 4683 free(*mvp, M_VNODE_MARKER); 4684 *mvp = NULL; 4685 } 4686 4687 static struct vnode * 4688 mnt_vnode_next_active(struct vnode **mvp, struct mount *mp) 4689 { 4690 struct vnode *vp, *nvp; 4691 4692 mtx_assert(&vnode_free_list_mtx, MA_OWNED); 4693 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch")); 4694 restart: 4695 vp = TAILQ_NEXT(*mvp, v_actfreelist); 4696 TAILQ_REMOVE(&mp->mnt_activevnodelist, *mvp, v_actfreelist); 4697 while (vp != NULL) { 4698 if (vp->v_type == VMARKER) { 4699 vp = TAILQ_NEXT(vp, v_actfreelist); 4700 continue; 4701 } 4702 if (!VI_TRYLOCK(vp)) { 4703 if (mp_ncpus == 1 || should_yield()) { 4704 TAILQ_INSERT_BEFORE(vp, *mvp, v_actfreelist); 4705 mtx_unlock(&vnode_free_list_mtx); 4706 kern_yield(PRI_USER); 4707 mtx_lock(&vnode_free_list_mtx); 4708 goto restart; 4709 } 4710 continue; 4711 } 4712 KASSERT(vp->v_type != VMARKER, ("locked marker %p", vp)); 4713 KASSERT(vp->v_mount == mp || vp->v_mount == NULL, 4714 ("alien vnode on the active list %p %p", vp, mp)); 4715 if (vp->v_mount == mp && (vp->v_iflag & VI_DOOMED) == 0) 4716 break; 4717 nvp = TAILQ_NEXT(vp, v_actfreelist); 4718 VI_UNLOCK(vp); 4719 vp = nvp; 4720 } 4721 4722 /* Check if we are done */ 4723 if (vp == NULL) { 4724 mtx_unlock(&vnode_free_list_mtx); 4725 mnt_vnode_markerfree_active(mvp, mp); 4726 return (NULL); 4727 } 4728 TAILQ_INSERT_AFTER(&mp->mnt_activevnodelist, vp, *mvp, v_actfreelist); 4729 mtx_unlock(&vnode_free_list_mtx); 4730 ASSERT_VI_LOCKED(vp, "active iter"); 4731 KASSERT((vp->v_iflag & VI_ACTIVE) != 0, ("Non-active vp %p", vp)); 4732 return (vp); 4733 } 4734 4735 struct vnode * 4736 __mnt_vnode_next_active(struct vnode **mvp, struct mount *mp) 4737 { 4738 4739 if (should_yield()) 4740 kern_yield(PRI_USER); 4741 mtx_lock(&vnode_free_list_mtx); 4742 return (mnt_vnode_next_active(mvp, mp)); 4743 } 4744 4745 struct vnode * 4746 __mnt_vnode_first_active(struct vnode **mvp, struct mount *mp) 4747 { 4748 struct vnode *vp; 4749 4750 *mvp = malloc(sizeof(struct vnode), M_VNODE_MARKER, M_WAITOK | M_ZERO); 4751 MNT_ILOCK(mp); 4752 MNT_REF(mp); 4753 MNT_IUNLOCK(mp); 4754 (*mvp)->v_type = VMARKER; 4755 (*mvp)->v_mount = mp; 4756 4757 mtx_lock(&vnode_free_list_mtx); 4758 vp = TAILQ_FIRST(&mp->mnt_activevnodelist); 4759 if (vp == NULL) { 4760 mtx_unlock(&vnode_free_list_mtx); 4761 mnt_vnode_markerfree_active(mvp, mp); 4762 return (NULL); 4763 } 4764 TAILQ_INSERT_BEFORE(vp, *mvp, v_actfreelist); 4765 return (mnt_vnode_next_active(mvp, mp)); 4766 } 4767 4768 void 4769 __mnt_vnode_markerfree_active(struct vnode **mvp, struct mount *mp) 4770 { 4771 4772 if (*mvp == NULL) 4773 return; 4774 4775 mtx_lock(&vnode_free_list_mtx); 4776 TAILQ_REMOVE(&mp->mnt_activevnodelist, *mvp, v_actfreelist); 4777 mtx_unlock(&vnode_free_list_mtx); 4778 mnt_vnode_markerfree_active(mvp, mp); 4779 } 4780