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_ddb.h" 45 #include "opt_mac.h" 46 47 #include <sys/param.h> 48 #include <sys/systm.h> 49 #include <sys/bio.h> 50 #include <sys/buf.h> 51 #include <sys/condvar.h> 52 #include <sys/conf.h> 53 #include <sys/dirent.h> 54 #include <sys/event.h> 55 #include <sys/eventhandler.h> 56 #include <sys/extattr.h> 57 #include <sys/file.h> 58 #include <sys/fcntl.h> 59 #include <sys/jail.h> 60 #include <sys/kdb.h> 61 #include <sys/kernel.h> 62 #include <sys/kthread.h> 63 #include <sys/lockf.h> 64 #include <sys/malloc.h> 65 #include <sys/mount.h> 66 #include <sys/namei.h> 67 #include <sys/priv.h> 68 #include <sys/reboot.h> 69 #include <sys/sleepqueue.h> 70 #include <sys/stat.h> 71 #include <sys/sysctl.h> 72 #include <sys/syslog.h> 73 #include <sys/vmmeter.h> 74 #include <sys/vnode.h> 75 76 #include <machine/stdarg.h> 77 78 #include <security/mac/mac_framework.h> 79 80 #include <vm/vm.h> 81 #include <vm/vm_object.h> 82 #include <vm/vm_extern.h> 83 #include <vm/pmap.h> 84 #include <vm/vm_map.h> 85 #include <vm/vm_page.h> 86 #include <vm/vm_kern.h> 87 #include <vm/uma.h> 88 89 #ifdef DDB 90 #include <ddb/ddb.h> 91 #endif 92 93 #define WI_MPSAFEQ 0 94 #define WI_GIANTQ 1 95 96 static MALLOC_DEFINE(M_NETADDR, "subr_export_host", "Export host address structure"); 97 98 static void delmntque(struct vnode *vp); 99 static int flushbuflist(struct bufv *bufv, int flags, struct bufobj *bo, 100 int slpflag, int slptimeo); 101 static void syncer_shutdown(void *arg, int howto); 102 static int vtryrecycle(struct vnode *vp); 103 static void vbusy(struct vnode *vp); 104 static void vinactive(struct vnode *, struct thread *); 105 static void v_incr_usecount(struct vnode *); 106 static void v_decr_usecount(struct vnode *); 107 static void v_decr_useonly(struct vnode *); 108 static void v_upgrade_usecount(struct vnode *); 109 static void vfree(struct vnode *); 110 static void vnlru_free(int); 111 static void vdestroy(struct vnode *); 112 static void vgonel(struct vnode *); 113 static void vfs_knllock(void *arg); 114 static void vfs_knlunlock(void *arg); 115 static int vfs_knllocked(void *arg); 116 117 118 /* 119 * Enable Giant pushdown based on whether or not the vm is mpsafe in this 120 * build. Without mpsafevm the buffer cache can not run Giant free. 121 */ 122 int mpsafe_vfs = 1; 123 TUNABLE_INT("debug.mpsafevfs", &mpsafe_vfs); 124 SYSCTL_INT(_debug, OID_AUTO, mpsafevfs, CTLFLAG_RD, &mpsafe_vfs, 0, 125 "MPSAFE VFS"); 126 127 /* 128 * Number of vnodes in existence. Increased whenever getnewvnode() 129 * allocates a new vnode, decreased on vdestroy() called on VI_DOOMed 130 * vnode. 131 */ 132 static unsigned long numvnodes; 133 134 SYSCTL_LONG(_vfs, OID_AUTO, numvnodes, CTLFLAG_RD, &numvnodes, 0, ""); 135 136 /* 137 * Conversion tables for conversion from vnode types to inode formats 138 * and back. 139 */ 140 enum vtype iftovt_tab[16] = { 141 VNON, VFIFO, VCHR, VNON, VDIR, VNON, VBLK, VNON, 142 VREG, VNON, VLNK, VNON, VSOCK, VNON, VNON, VBAD, 143 }; 144 int vttoif_tab[10] = { 145 0, S_IFREG, S_IFDIR, S_IFBLK, S_IFCHR, S_IFLNK, 146 S_IFSOCK, S_IFIFO, S_IFMT, S_IFMT 147 }; 148 149 /* 150 * List of vnodes that are ready for recycling. 151 */ 152 static TAILQ_HEAD(freelst, vnode) vnode_free_list; 153 154 /* 155 * Free vnode target. Free vnodes may simply be files which have been stat'd 156 * but not read. This is somewhat common, and a small cache of such files 157 * should be kept to avoid recreation costs. 158 */ 159 static u_long wantfreevnodes; 160 SYSCTL_LONG(_vfs, OID_AUTO, wantfreevnodes, CTLFLAG_RW, &wantfreevnodes, 0, ""); 161 /* Number of vnodes in the free list. */ 162 static u_long freevnodes; 163 SYSCTL_LONG(_vfs, OID_AUTO, freevnodes, CTLFLAG_RD, &freevnodes, 0, ""); 164 165 /* 166 * Various variables used for debugging the new implementation of 167 * reassignbuf(). 168 * XXX these are probably of (very) limited utility now. 169 */ 170 static int reassignbufcalls; 171 SYSCTL_INT(_vfs, OID_AUTO, reassignbufcalls, CTLFLAG_RW, &reassignbufcalls, 0, ""); 172 173 /* 174 * Cache for the mount type id assigned to NFS. This is used for 175 * special checks in nfs/nfs_nqlease.c and vm/vnode_pager.c. 176 */ 177 int nfs_mount_type = -1; 178 179 /* To keep more than one thread at a time from running vfs_getnewfsid */ 180 static struct mtx mntid_mtx; 181 182 /* 183 * Lock for any access to the following: 184 * vnode_free_list 185 * numvnodes 186 * freevnodes 187 */ 188 static struct mtx vnode_free_list_mtx; 189 190 /* Publicly exported FS */ 191 struct nfs_public nfs_pub; 192 193 /* Zone for allocation of new vnodes - used exclusively by getnewvnode() */ 194 static uma_zone_t vnode_zone; 195 static uma_zone_t vnodepoll_zone; 196 197 /* Set to 1 to print out reclaim of active vnodes */ 198 int prtactive; 199 200 /* 201 * The workitem queue. 202 * 203 * It is useful to delay writes of file data and filesystem metadata 204 * for tens of seconds so that quickly created and deleted files need 205 * not waste disk bandwidth being created and removed. To realize this, 206 * we append vnodes to a "workitem" queue. When running with a soft 207 * updates implementation, most pending metadata dependencies should 208 * not wait for more than a few seconds. Thus, mounted on block devices 209 * are delayed only about a half the time that file data is delayed. 210 * Similarly, directory updates are more critical, so are only delayed 211 * about a third the time that file data is delayed. Thus, there are 212 * SYNCER_MAXDELAY queues that are processed round-robin at a rate of 213 * one each second (driven off the filesystem syncer process). The 214 * syncer_delayno variable indicates the next queue that is to be processed. 215 * Items that need to be processed soon are placed in this queue: 216 * 217 * syncer_workitem_pending[syncer_delayno] 218 * 219 * A delay of fifteen seconds is done by placing the request fifteen 220 * entries later in the queue: 221 * 222 * syncer_workitem_pending[(syncer_delayno + 15) & syncer_mask] 223 * 224 */ 225 static int syncer_delayno; 226 static long syncer_mask; 227 LIST_HEAD(synclist, bufobj); 228 static struct synclist *syncer_workitem_pending[2]; 229 /* 230 * The sync_mtx protects: 231 * bo->bo_synclist 232 * sync_vnode_count 233 * syncer_delayno 234 * syncer_state 235 * syncer_workitem_pending 236 * syncer_worklist_len 237 * rushjob 238 */ 239 static struct mtx sync_mtx; 240 static struct cv sync_wakeup; 241 242 #define SYNCER_MAXDELAY 32 243 static int syncer_maxdelay = SYNCER_MAXDELAY; /* maximum delay time */ 244 static int syncdelay = 30; /* max time to delay syncing data */ 245 static int filedelay = 30; /* time to delay syncing files */ 246 SYSCTL_INT(_kern, OID_AUTO, filedelay, CTLFLAG_RW, &filedelay, 0, ""); 247 static int dirdelay = 29; /* time to delay syncing directories */ 248 SYSCTL_INT(_kern, OID_AUTO, dirdelay, CTLFLAG_RW, &dirdelay, 0, ""); 249 static int metadelay = 28; /* time to delay syncing metadata */ 250 SYSCTL_INT(_kern, OID_AUTO, metadelay, CTLFLAG_RW, &metadelay, 0, ""); 251 static int rushjob; /* number of slots to run ASAP */ 252 static int stat_rush_requests; /* number of times I/O speeded up */ 253 SYSCTL_INT(_debug, OID_AUTO, rush_requests, CTLFLAG_RW, &stat_rush_requests, 0, ""); 254 255 /* 256 * When shutting down the syncer, run it at four times normal speed. 257 */ 258 #define SYNCER_SHUTDOWN_SPEEDUP 4 259 static int sync_vnode_count; 260 static int syncer_worklist_len; 261 static enum { SYNCER_RUNNING, SYNCER_SHUTTING_DOWN, SYNCER_FINAL_DELAY } 262 syncer_state; 263 264 /* 265 * Number of vnodes we want to exist at any one time. This is mostly used 266 * to size hash tables in vnode-related code. It is normally not used in 267 * getnewvnode(), as wantfreevnodes is normally nonzero.) 268 * 269 * XXX desiredvnodes is historical cruft and should not exist. 270 */ 271 int desiredvnodes; 272 SYSCTL_INT(_kern, KERN_MAXVNODES, maxvnodes, CTLFLAG_RW, 273 &desiredvnodes, 0, "Maximum number of vnodes"); 274 SYSCTL_INT(_kern, OID_AUTO, minvnodes, CTLFLAG_RW, 275 &wantfreevnodes, 0, "Minimum number of vnodes (legacy)"); 276 static int vnlru_nowhere; 277 SYSCTL_INT(_debug, OID_AUTO, vnlru_nowhere, CTLFLAG_RW, 278 &vnlru_nowhere, 0, "Number of times the vnlru process ran without success"); 279 280 /* 281 * Macros to control when a vnode is freed and recycled. All require 282 * the vnode interlock. 283 */ 284 #define VCANRECYCLE(vp) (((vp)->v_iflag & VI_FREE) && !(vp)->v_holdcnt) 285 #define VSHOULDFREE(vp) (!((vp)->v_iflag & VI_FREE) && !(vp)->v_holdcnt) 286 #define VSHOULDBUSY(vp) (((vp)->v_iflag & VI_FREE) && (vp)->v_holdcnt) 287 288 289 /* 290 * Initialize the vnode management data structures. 291 */ 292 #ifndef MAXVNODES_MAX 293 #define MAXVNODES_MAX 100000 294 #endif 295 static void 296 vntblinit(void *dummy __unused) 297 { 298 299 /* 300 * Desiredvnodes is a function of the physical memory size and 301 * the kernel's heap size. Specifically, desiredvnodes scales 302 * in proportion to the physical memory size until two fifths 303 * of the kernel's heap size is consumed by vnodes and vm 304 * objects. 305 */ 306 desiredvnodes = min(maxproc + cnt.v_page_count / 4, 2 * vm_kmem_size / 307 (5 * (sizeof(struct vm_object) + sizeof(struct vnode)))); 308 if (desiredvnodes > MAXVNODES_MAX) { 309 if (bootverbose) 310 printf("Reducing kern.maxvnodes %d -> %d\n", 311 desiredvnodes, MAXVNODES_MAX); 312 desiredvnodes = MAXVNODES_MAX; 313 } 314 wantfreevnodes = desiredvnodes / 4; 315 mtx_init(&mntid_mtx, "mntid", NULL, MTX_DEF); 316 TAILQ_INIT(&vnode_free_list); 317 mtx_init(&vnode_free_list_mtx, "vnode_free_list", NULL, MTX_DEF); 318 vnode_zone = uma_zcreate("VNODE", sizeof (struct vnode), NULL, NULL, 319 NULL, NULL, UMA_ALIGN_PTR, 0); 320 vnodepoll_zone = uma_zcreate("VNODEPOLL", sizeof (struct vpollinfo), 321 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); 322 /* 323 * Initialize the filesystem syncer. 324 */ 325 syncer_workitem_pending[WI_MPSAFEQ] = hashinit(syncer_maxdelay, M_VNODE, 326 &syncer_mask); 327 syncer_workitem_pending[WI_GIANTQ] = hashinit(syncer_maxdelay, M_VNODE, 328 &syncer_mask); 329 syncer_maxdelay = syncer_mask + 1; 330 mtx_init(&sync_mtx, "Syncer mtx", NULL, MTX_DEF); 331 cv_init(&sync_wakeup, "syncer"); 332 } 333 SYSINIT(vfs, SI_SUB_VFS, SI_ORDER_FIRST, vntblinit, NULL); 334 335 336 /* 337 * Mark a mount point as busy. Used to synchronize access and to delay 338 * unmounting. Interlock is not released on failure. 339 */ 340 int 341 vfs_busy(struct mount *mp, int flags, struct mtx *interlkp) 342 { 343 int lkflags; 344 345 MNT_ILOCK(mp); 346 MNT_REF(mp); 347 if (mp->mnt_kern_flag & MNTK_UNMOUNT) { 348 if (flags & LK_NOWAIT) { 349 MNT_REL(mp); 350 MNT_IUNLOCK(mp); 351 return (ENOENT); 352 } 353 if (interlkp) 354 mtx_unlock(interlkp); 355 mp->mnt_kern_flag |= MNTK_MWAIT; 356 /* 357 * Since all busy locks are shared except the exclusive 358 * lock granted when unmounting, the only place that a 359 * wakeup needs to be done is at the release of the 360 * exclusive lock at the end of dounmount. 361 */ 362 msleep(mp, MNT_MTX(mp), PVFS, "vfs_busy", 0); 363 MNT_REL(mp); 364 MNT_IUNLOCK(mp); 365 if (interlkp) 366 mtx_lock(interlkp); 367 return (ENOENT); 368 } 369 if (interlkp) 370 mtx_unlock(interlkp); 371 lkflags = LK_SHARED | LK_INTERLOCK; 372 if (lockmgr(&mp->mnt_lock, lkflags, MNT_MTX(mp))) 373 panic("vfs_busy: unexpected lock failure"); 374 return (0); 375 } 376 377 /* 378 * Free a busy filesystem. 379 */ 380 void 381 vfs_unbusy(struct mount *mp) 382 { 383 384 lockmgr(&mp->mnt_lock, LK_RELEASE, NULL); 385 vfs_rel(mp); 386 } 387 388 /* 389 * Lookup a mount point by filesystem identifier. 390 */ 391 struct mount * 392 vfs_getvfs(fsid_t *fsid) 393 { 394 struct mount *mp; 395 396 mtx_lock(&mountlist_mtx); 397 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 398 if (mp->mnt_stat.f_fsid.val[0] == fsid->val[0] && 399 mp->mnt_stat.f_fsid.val[1] == fsid->val[1]) { 400 vfs_ref(mp); 401 mtx_unlock(&mountlist_mtx); 402 return (mp); 403 } 404 } 405 mtx_unlock(&mountlist_mtx); 406 return ((struct mount *) 0); 407 } 408 409 /* 410 * Check if a user can access privileged mount options. 411 */ 412 int 413 vfs_suser(struct mount *mp, struct thread *td) 414 { 415 int error; 416 417 /* 418 * If the thread is jailed, but this is not a jail-friendly file 419 * system, deny immediately. 420 */ 421 if (jailed(td->td_ucred) && !(mp->mnt_vfc->vfc_flags & VFCF_JAIL)) 422 return (EPERM); 423 424 /* 425 * If the file system was mounted outside a jail and a jailed thread 426 * tries to access it, deny immediately. 427 */ 428 if (!jailed(mp->mnt_cred) && jailed(td->td_ucred)) 429 return (EPERM); 430 431 /* 432 * If the file system was mounted inside different jail that the jail of 433 * the calling thread, deny immediately. 434 */ 435 if (jailed(mp->mnt_cred) && jailed(td->td_ucred) && 436 mp->mnt_cred->cr_prison != td->td_ucred->cr_prison) { 437 return (EPERM); 438 } 439 440 if ((mp->mnt_flag & MNT_USER) == 0 || 441 mp->mnt_cred->cr_uid != td->td_ucred->cr_uid) { 442 if ((error = priv_check(td, PRIV_VFS_MOUNT_OWNER)) != 0) 443 return (error); 444 } 445 return (0); 446 } 447 448 /* 449 * Get a new unique fsid. Try to make its val[0] unique, since this value 450 * will be used to create fake device numbers for stat(). Also try (but 451 * not so hard) make its val[0] unique mod 2^16, since some emulators only 452 * support 16-bit device numbers. We end up with unique val[0]'s for the 453 * first 2^16 calls and unique val[0]'s mod 2^16 for the first 2^8 calls. 454 * 455 * Keep in mind that several mounts may be running in parallel. Starting 456 * the search one past where the previous search terminated is both a 457 * micro-optimization and a defense against returning the same fsid to 458 * different mounts. 459 */ 460 void 461 vfs_getnewfsid(struct mount *mp) 462 { 463 static u_int16_t mntid_base; 464 struct mount *nmp; 465 fsid_t tfsid; 466 int mtype; 467 468 mtx_lock(&mntid_mtx); 469 mtype = mp->mnt_vfc->vfc_typenum; 470 tfsid.val[1] = mtype; 471 mtype = (mtype & 0xFF) << 24; 472 for (;;) { 473 tfsid.val[0] = makedev(255, 474 mtype | ((mntid_base & 0xFF00) << 8) | (mntid_base & 0xFF)); 475 mntid_base++; 476 if ((nmp = vfs_getvfs(&tfsid)) == NULL) 477 break; 478 vfs_rel(nmp); 479 } 480 mp->mnt_stat.f_fsid.val[0] = tfsid.val[0]; 481 mp->mnt_stat.f_fsid.val[1] = tfsid.val[1]; 482 mtx_unlock(&mntid_mtx); 483 } 484 485 /* 486 * Knob to control the precision of file timestamps: 487 * 488 * 0 = seconds only; nanoseconds zeroed. 489 * 1 = seconds and nanoseconds, accurate within 1/HZ. 490 * 2 = seconds and nanoseconds, truncated to microseconds. 491 * >=3 = seconds and nanoseconds, maximum precision. 492 */ 493 enum { TSP_SEC, TSP_HZ, TSP_USEC, TSP_NSEC }; 494 495 static int timestamp_precision = TSP_SEC; 496 SYSCTL_INT(_vfs, OID_AUTO, timestamp_precision, CTLFLAG_RW, 497 ×tamp_precision, 0, ""); 498 499 /* 500 * Get a current timestamp. 501 */ 502 void 503 vfs_timestamp(struct timespec *tsp) 504 { 505 struct timeval tv; 506 507 switch (timestamp_precision) { 508 case TSP_SEC: 509 tsp->tv_sec = time_second; 510 tsp->tv_nsec = 0; 511 break; 512 case TSP_HZ: 513 getnanotime(tsp); 514 break; 515 case TSP_USEC: 516 microtime(&tv); 517 TIMEVAL_TO_TIMESPEC(&tv, tsp); 518 break; 519 case TSP_NSEC: 520 default: 521 nanotime(tsp); 522 break; 523 } 524 } 525 526 /* 527 * Set vnode attributes to VNOVAL 528 */ 529 void 530 vattr_null(struct vattr *vap) 531 { 532 533 vap->va_type = VNON; 534 vap->va_size = VNOVAL; 535 vap->va_bytes = VNOVAL; 536 vap->va_mode = VNOVAL; 537 vap->va_nlink = VNOVAL; 538 vap->va_uid = VNOVAL; 539 vap->va_gid = VNOVAL; 540 vap->va_fsid = VNOVAL; 541 vap->va_fileid = VNOVAL; 542 vap->va_blocksize = VNOVAL; 543 vap->va_rdev = VNOVAL; 544 vap->va_atime.tv_sec = VNOVAL; 545 vap->va_atime.tv_nsec = VNOVAL; 546 vap->va_mtime.tv_sec = VNOVAL; 547 vap->va_mtime.tv_nsec = VNOVAL; 548 vap->va_ctime.tv_sec = VNOVAL; 549 vap->va_ctime.tv_nsec = VNOVAL; 550 vap->va_birthtime.tv_sec = VNOVAL; 551 vap->va_birthtime.tv_nsec = VNOVAL; 552 vap->va_flags = VNOVAL; 553 vap->va_gen = VNOVAL; 554 vap->va_vaflags = 0; 555 } 556 557 /* 558 * This routine is called when we have too many vnodes. It attempts 559 * to free <count> vnodes and will potentially free vnodes that still 560 * have VM backing store (VM backing store is typically the cause 561 * of a vnode blowout so we want to do this). Therefore, this operation 562 * is not considered cheap. 563 * 564 * A number of conditions may prevent a vnode from being reclaimed. 565 * the buffer cache may have references on the vnode, a directory 566 * vnode may still have references due to the namei cache representing 567 * underlying files, or the vnode may be in active use. It is not 568 * desireable to reuse such vnodes. These conditions may cause the 569 * number of vnodes to reach some minimum value regardless of what 570 * you set kern.maxvnodes to. Do not set kern.maxvnodes too low. 571 */ 572 static int 573 vlrureclaim(struct mount *mp) 574 { 575 struct vnode *vp; 576 int done; 577 int trigger; 578 int usevnodes; 579 int count; 580 581 /* 582 * Calculate the trigger point, don't allow user 583 * screwups to blow us up. This prevents us from 584 * recycling vnodes with lots of resident pages. We 585 * aren't trying to free memory, we are trying to 586 * free vnodes. 587 */ 588 usevnodes = desiredvnodes; 589 if (usevnodes <= 0) 590 usevnodes = 1; 591 trigger = cnt.v_page_count * 2 / usevnodes; 592 done = 0; 593 vn_start_write(NULL, &mp, V_WAIT); 594 MNT_ILOCK(mp); 595 count = mp->mnt_nvnodelistsize / 10 + 1; 596 while (count != 0) { 597 vp = TAILQ_FIRST(&mp->mnt_nvnodelist); 598 while (vp != NULL && vp->v_type == VMARKER) 599 vp = TAILQ_NEXT(vp, v_nmntvnodes); 600 if (vp == NULL) 601 break; 602 TAILQ_REMOVE(&mp->mnt_nvnodelist, vp, v_nmntvnodes); 603 TAILQ_INSERT_TAIL(&mp->mnt_nvnodelist, vp, v_nmntvnodes); 604 --count; 605 if (!VI_TRYLOCK(vp)) 606 goto next_iter; 607 /* 608 * If it's been deconstructed already, it's still 609 * referenced, or it exceeds the trigger, skip it. 610 */ 611 if (vp->v_usecount || !LIST_EMPTY(&(vp)->v_cache_src) || 612 (vp->v_iflag & VI_DOOMED) != 0 || (vp->v_object != NULL && 613 vp->v_object->resident_page_count > trigger)) { 614 VI_UNLOCK(vp); 615 goto next_iter; 616 } 617 MNT_IUNLOCK(mp); 618 vholdl(vp); 619 if (VOP_LOCK(vp, LK_INTERLOCK|LK_EXCLUSIVE|LK_NOWAIT)) { 620 vdrop(vp); 621 goto next_iter_mntunlocked; 622 } 623 VI_LOCK(vp); 624 /* 625 * v_usecount may have been bumped after VOP_LOCK() dropped 626 * the vnode interlock and before it was locked again. 627 * 628 * It is not necessary to recheck VI_DOOMED because it can 629 * only be set by another thread that holds both the vnode 630 * lock and vnode interlock. If another thread has the 631 * vnode lock before we get to VOP_LOCK() and obtains the 632 * vnode interlock after VOP_LOCK() drops the vnode 633 * interlock, the other thread will be unable to drop the 634 * vnode lock before our VOP_LOCK() call fails. 635 */ 636 if (vp->v_usecount || !LIST_EMPTY(&(vp)->v_cache_src) || 637 (vp->v_object != NULL && 638 vp->v_object->resident_page_count > trigger)) { 639 VOP_UNLOCK(vp, LK_INTERLOCK); 640 goto next_iter_mntunlocked; 641 } 642 KASSERT((vp->v_iflag & VI_DOOMED) == 0, 643 ("VI_DOOMED unexpectedly detected in vlrureclaim()")); 644 vgonel(vp); 645 VOP_UNLOCK(vp, 0); 646 vdropl(vp); 647 done++; 648 next_iter_mntunlocked: 649 if ((count % 256) != 0) 650 goto relock_mnt; 651 goto yield; 652 next_iter: 653 if ((count % 256) != 0) 654 continue; 655 MNT_IUNLOCK(mp); 656 yield: 657 uio_yield(); 658 relock_mnt: 659 MNT_ILOCK(mp); 660 } 661 MNT_IUNLOCK(mp); 662 vn_finished_write(mp); 663 return done; 664 } 665 666 /* 667 * Attempt to keep the free list at wantfreevnodes length. 668 */ 669 static void 670 vnlru_free(int count) 671 { 672 struct vnode *vp; 673 int vfslocked; 674 675 mtx_assert(&vnode_free_list_mtx, MA_OWNED); 676 for (; count > 0; count--) { 677 vp = TAILQ_FIRST(&vnode_free_list); 678 /* 679 * The list can be modified while the free_list_mtx 680 * has been dropped and vp could be NULL here. 681 */ 682 if (!vp) 683 break; 684 VNASSERT(vp->v_op != NULL, vp, 685 ("vnlru_free: vnode already reclaimed.")); 686 TAILQ_REMOVE(&vnode_free_list, vp, v_freelist); 687 /* 688 * Don't recycle if we can't get the interlock. 689 */ 690 if (!VI_TRYLOCK(vp)) { 691 TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_freelist); 692 continue; 693 } 694 VNASSERT(VCANRECYCLE(vp), vp, 695 ("vp inconsistent on freelist")); 696 freevnodes--; 697 vp->v_iflag &= ~VI_FREE; 698 vholdl(vp); 699 mtx_unlock(&vnode_free_list_mtx); 700 VI_UNLOCK(vp); 701 vfslocked = VFS_LOCK_GIANT(vp->v_mount); 702 vtryrecycle(vp); 703 VFS_UNLOCK_GIANT(vfslocked); 704 /* 705 * If the recycled succeeded this vdrop will actually free 706 * the vnode. If not it will simply place it back on 707 * the free list. 708 */ 709 vdrop(vp); 710 mtx_lock(&vnode_free_list_mtx); 711 } 712 } 713 /* 714 * Attempt to recycle vnodes in a context that is always safe to block. 715 * Calling vlrurecycle() from the bowels of filesystem code has some 716 * interesting deadlock problems. 717 */ 718 static struct proc *vnlruproc; 719 static int vnlruproc_sig; 720 721 static void 722 vnlru_proc(void) 723 { 724 struct mount *mp, *nmp; 725 int done; 726 struct proc *p = vnlruproc; 727 728 EVENTHANDLER_REGISTER(shutdown_pre_sync, kproc_shutdown, p, 729 SHUTDOWN_PRI_FIRST); 730 731 mtx_lock(&Giant); 732 733 for (;;) { 734 kproc_suspend_check(p); 735 mtx_lock(&vnode_free_list_mtx); 736 if (freevnodes > wantfreevnodes) 737 vnlru_free(freevnodes - wantfreevnodes); 738 if (numvnodes <= desiredvnodes * 9 / 10) { 739 vnlruproc_sig = 0; 740 wakeup(&vnlruproc_sig); 741 msleep(vnlruproc, &vnode_free_list_mtx, 742 PVFS|PDROP, "vlruwt", hz); 743 continue; 744 } 745 mtx_unlock(&vnode_free_list_mtx); 746 done = 0; 747 mtx_lock(&mountlist_mtx); 748 for (mp = TAILQ_FIRST(&mountlist); mp != NULL; mp = nmp) { 749 int vfsunlocked; 750 if (vfs_busy(mp, LK_NOWAIT, &mountlist_mtx)) { 751 nmp = TAILQ_NEXT(mp, mnt_list); 752 continue; 753 } 754 if (!VFS_NEEDSGIANT(mp)) { 755 mtx_unlock(&Giant); 756 vfsunlocked = 1; 757 } else 758 vfsunlocked = 0; 759 done += vlrureclaim(mp); 760 if (vfsunlocked) 761 mtx_lock(&Giant); 762 mtx_lock(&mountlist_mtx); 763 nmp = TAILQ_NEXT(mp, mnt_list); 764 vfs_unbusy(mp); 765 } 766 mtx_unlock(&mountlist_mtx); 767 if (done == 0) { 768 EVENTHANDLER_INVOKE(vfs_lowvnodes, desiredvnodes / 10); 769 #if 0 770 /* These messages are temporary debugging aids */ 771 if (vnlru_nowhere < 5) 772 printf("vnlru process getting nowhere..\n"); 773 else if (vnlru_nowhere == 5) 774 printf("vnlru process messages stopped.\n"); 775 #endif 776 vnlru_nowhere++; 777 tsleep(vnlruproc, PPAUSE, "vlrup", hz * 3); 778 } else 779 uio_yield(); 780 } 781 } 782 783 static struct kproc_desc vnlru_kp = { 784 "vnlru", 785 vnlru_proc, 786 &vnlruproc 787 }; 788 SYSINIT(vnlru, SI_SUB_KTHREAD_UPDATE, SI_ORDER_FIRST, kproc_start, 789 &vnlru_kp); 790 791 /* 792 * Routines having to do with the management of the vnode table. 793 */ 794 795 static void 796 vdestroy(struct vnode *vp) 797 { 798 struct bufobj *bo; 799 800 CTR1(KTR_VFS, "vdestroy vp %p", vp); 801 mtx_lock(&vnode_free_list_mtx); 802 numvnodes--; 803 mtx_unlock(&vnode_free_list_mtx); 804 bo = &vp->v_bufobj; 805 VNASSERT((vp->v_iflag & VI_FREE) == 0, vp, 806 ("cleaned vnode still on the free list.")); 807 VNASSERT(vp->v_data == NULL, vp, ("cleaned vnode isn't")); 808 VNASSERT(vp->v_holdcnt == 0, vp, ("Non-zero hold count")); 809 VNASSERT(vp->v_usecount == 0, vp, ("Non-zero use count")); 810 VNASSERT(vp->v_writecount == 0, vp, ("Non-zero write count")); 811 VNASSERT(bo->bo_numoutput == 0, vp, ("Clean vnode has pending I/O's")); 812 VNASSERT(bo->bo_clean.bv_cnt == 0, vp, ("cleanbufcnt not 0")); 813 VNASSERT(bo->bo_clean.bv_root == NULL, vp, ("cleanblkroot not NULL")); 814 VNASSERT(bo->bo_dirty.bv_cnt == 0, vp, ("dirtybufcnt not 0")); 815 VNASSERT(bo->bo_dirty.bv_root == NULL, vp, ("dirtyblkroot not NULL")); 816 VNASSERT(TAILQ_EMPTY(&vp->v_cache_dst), vp, ("vp has namecache dst")); 817 VNASSERT(LIST_EMPTY(&vp->v_cache_src), vp, ("vp has namecache src")); 818 VI_UNLOCK(vp); 819 #ifdef MAC 820 mac_vnode_destroy(vp); 821 #endif 822 if (vp->v_pollinfo != NULL) { 823 knlist_destroy(&vp->v_pollinfo->vpi_selinfo.si_note); 824 mtx_destroy(&vp->v_pollinfo->vpi_lock); 825 uma_zfree(vnodepoll_zone, vp->v_pollinfo); 826 } 827 #ifdef INVARIANTS 828 /* XXX Elsewhere we can detect an already freed vnode via NULL v_op. */ 829 vp->v_op = NULL; 830 #endif 831 lockdestroy(vp->v_vnlock); 832 mtx_destroy(&vp->v_interlock); 833 mtx_destroy(BO_MTX(bo)); 834 uma_zfree(vnode_zone, vp); 835 } 836 837 /* 838 * Try to recycle a freed vnode. We abort if anyone picks up a reference 839 * before we actually vgone(). This function must be called with the vnode 840 * held to prevent the vnode from being returned to the free list midway 841 * through vgone(). 842 */ 843 static int 844 vtryrecycle(struct vnode *vp) 845 { 846 struct mount *vnmp; 847 848 CTR1(KTR_VFS, "vtryrecycle: trying vp %p", vp); 849 VNASSERT(vp->v_holdcnt, vp, 850 ("vtryrecycle: Recycling vp %p without a reference.", vp)); 851 /* 852 * This vnode may found and locked via some other list, if so we 853 * can't recycle it yet. 854 */ 855 if (VOP_LOCK(vp, LK_EXCLUSIVE | LK_NOWAIT) != 0) 856 return (EWOULDBLOCK); 857 /* 858 * Don't recycle if its filesystem is being suspended. 859 */ 860 if (vn_start_write(vp, &vnmp, V_NOWAIT) != 0) { 861 VOP_UNLOCK(vp, 0); 862 return (EBUSY); 863 } 864 /* 865 * If we got this far, we need to acquire the interlock and see if 866 * anyone picked up this vnode from another list. If not, we will 867 * mark it with DOOMED via vgonel() so that anyone who does find it 868 * will skip over it. 869 */ 870 VI_LOCK(vp); 871 if (vp->v_usecount) { 872 VOP_UNLOCK(vp, LK_INTERLOCK); 873 vn_finished_write(vnmp); 874 return (EBUSY); 875 } 876 if ((vp->v_iflag & VI_DOOMED) == 0) 877 vgonel(vp); 878 VOP_UNLOCK(vp, LK_INTERLOCK); 879 vn_finished_write(vnmp); 880 CTR1(KTR_VFS, "vtryrecycle: recycled vp %p", vp); 881 return (0); 882 } 883 884 /* 885 * Return the next vnode from the free list. 886 */ 887 int 888 getnewvnode(const char *tag, struct mount *mp, struct vop_vector *vops, 889 struct vnode **vpp) 890 { 891 struct vnode *vp = NULL; 892 struct bufobj *bo; 893 894 mtx_lock(&vnode_free_list_mtx); 895 /* 896 * Lend our context to reclaim vnodes if they've exceeded the max. 897 */ 898 if (freevnodes > wantfreevnodes) 899 vnlru_free(1); 900 /* 901 * Wait for available vnodes. 902 */ 903 if (numvnodes > desiredvnodes) { 904 if (mp != NULL && (mp->mnt_kern_flag & MNTK_SUSPEND)) { 905 /* 906 * File system is beeing suspended, we cannot risk a 907 * deadlock here, so allocate new vnode anyway. 908 */ 909 if (freevnodes > wantfreevnodes) 910 vnlru_free(freevnodes - wantfreevnodes); 911 goto alloc; 912 } 913 if (vnlruproc_sig == 0) { 914 vnlruproc_sig = 1; /* avoid unnecessary wakeups */ 915 wakeup(vnlruproc); 916 } 917 msleep(&vnlruproc_sig, &vnode_free_list_mtx, PVFS, 918 "vlruwk", hz); 919 #if 0 /* XXX Not all VFS_VGET/ffs_vget callers check returns. */ 920 if (numvnodes > desiredvnodes) { 921 mtx_unlock(&vnode_free_list_mtx); 922 return (ENFILE); 923 } 924 #endif 925 } 926 alloc: 927 numvnodes++; 928 mtx_unlock(&vnode_free_list_mtx); 929 vp = (struct vnode *) uma_zalloc(vnode_zone, M_WAITOK|M_ZERO); 930 /* 931 * Setup locks. 932 */ 933 vp->v_vnlock = &vp->v_lock; 934 mtx_init(&vp->v_interlock, "vnode interlock", NULL, MTX_DEF); 935 /* 936 * By default, don't allow shared locks unless filesystems 937 * opt-in. 938 */ 939 lockinit(vp->v_vnlock, PVFS, tag, VLKTIMEOUT, LK_NOSHARE); 940 /* 941 * Initialize bufobj. 942 */ 943 bo = &vp->v_bufobj; 944 bo->__bo_vnode = vp; 945 mtx_init(BO_MTX(bo), "bufobj interlock", NULL, MTX_DEF); 946 bo->bo_ops = &buf_ops_bio; 947 bo->bo_private = vp; 948 TAILQ_INIT(&bo->bo_clean.bv_hd); 949 TAILQ_INIT(&bo->bo_dirty.bv_hd); 950 /* 951 * Initialize namecache. 952 */ 953 LIST_INIT(&vp->v_cache_src); 954 TAILQ_INIT(&vp->v_cache_dst); 955 /* 956 * Finalize various vnode identity bits. 957 */ 958 vp->v_type = VNON; 959 vp->v_tag = tag; 960 vp->v_op = vops; 961 v_incr_usecount(vp); 962 vp->v_data = 0; 963 #ifdef MAC 964 mac_vnode_init(vp); 965 if (mp != NULL && (mp->mnt_flag & MNT_MULTILABEL) == 0) 966 mac_vnode_associate_singlelabel(mp, vp); 967 else if (mp == NULL && vops != &dead_vnodeops) 968 printf("NULL mp in getnewvnode()\n"); 969 #endif 970 if (mp != NULL) { 971 bo->bo_bsize = mp->mnt_stat.f_iosize; 972 if ((mp->mnt_kern_flag & MNTK_NOKNOTE) != 0) 973 vp->v_vflag |= VV_NOKNOTE; 974 } 975 976 CTR2(KTR_VFS, "getnewvnode: mp %p vp %p", mp, vp); 977 *vpp = vp; 978 return (0); 979 } 980 981 /* 982 * Delete from old mount point vnode list, if on one. 983 */ 984 static void 985 delmntque(struct vnode *vp) 986 { 987 struct mount *mp; 988 989 mp = vp->v_mount; 990 if (mp == NULL) 991 return; 992 MNT_ILOCK(mp); 993 vp->v_mount = NULL; 994 VNASSERT(mp->mnt_nvnodelistsize > 0, vp, 995 ("bad mount point vnode list size")); 996 TAILQ_REMOVE(&mp->mnt_nvnodelist, vp, v_nmntvnodes); 997 mp->mnt_nvnodelistsize--; 998 MNT_REL(mp); 999 MNT_IUNLOCK(mp); 1000 } 1001 1002 static void 1003 insmntque_stddtr(struct vnode *vp, void *dtr_arg) 1004 { 1005 1006 vp->v_data = NULL; 1007 vp->v_op = &dead_vnodeops; 1008 /* XXX non mp-safe fs may still call insmntque with vnode 1009 unlocked */ 1010 if (!VOP_ISLOCKED(vp)) 1011 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 1012 vgone(vp); 1013 vput(vp); 1014 } 1015 1016 /* 1017 * Insert into list of vnodes for the new mount point, if available. 1018 */ 1019 int 1020 insmntque1(struct vnode *vp, struct mount *mp, 1021 void (*dtr)(struct vnode *, void *), void *dtr_arg) 1022 { 1023 int locked; 1024 1025 KASSERT(vp->v_mount == NULL, 1026 ("insmntque: vnode already on per mount vnode list")); 1027 VNASSERT(mp != NULL, vp, ("Don't call insmntque(foo, NULL)")); 1028 #ifdef DEBUG_VFS_LOCKS 1029 if (!VFS_NEEDSGIANT(mp)) 1030 ASSERT_VOP_ELOCKED(vp, 1031 "insmntque: mp-safe fs and non-locked vp"); 1032 #endif 1033 MNT_ILOCK(mp); 1034 if ((mp->mnt_kern_flag & MNTK_NOINSMNTQ) != 0 && 1035 ((mp->mnt_kern_flag & MNTK_UNMOUNTF) != 0 || 1036 mp->mnt_nvnodelistsize == 0)) { 1037 locked = VOP_ISLOCKED(vp); 1038 if (!locked || (locked == LK_EXCLUSIVE && 1039 (vp->v_vflag & VV_FORCEINSMQ) == 0)) { 1040 MNT_IUNLOCK(mp); 1041 if (dtr != NULL) 1042 dtr(vp, dtr_arg); 1043 return (EBUSY); 1044 } 1045 } 1046 vp->v_mount = mp; 1047 MNT_REF(mp); 1048 TAILQ_INSERT_TAIL(&mp->mnt_nvnodelist, vp, v_nmntvnodes); 1049 VNASSERT(mp->mnt_nvnodelistsize >= 0, vp, 1050 ("neg mount point vnode list size")); 1051 mp->mnt_nvnodelistsize++; 1052 MNT_IUNLOCK(mp); 1053 return (0); 1054 } 1055 1056 int 1057 insmntque(struct vnode *vp, struct mount *mp) 1058 { 1059 1060 return (insmntque1(vp, mp, insmntque_stddtr, NULL)); 1061 } 1062 1063 /* 1064 * Flush out and invalidate all buffers associated with a bufobj 1065 * Called with the underlying object locked. 1066 */ 1067 int 1068 bufobj_invalbuf(struct bufobj *bo, int flags, struct thread *td, int slpflag, 1069 int slptimeo) 1070 { 1071 int error; 1072 1073 BO_LOCK(bo); 1074 if (flags & V_SAVE) { 1075 error = bufobj_wwait(bo, slpflag, slptimeo); 1076 if (error) { 1077 BO_UNLOCK(bo); 1078 return (error); 1079 } 1080 if (bo->bo_dirty.bv_cnt > 0) { 1081 BO_UNLOCK(bo); 1082 if ((error = BO_SYNC(bo, MNT_WAIT, td)) != 0) 1083 return (error); 1084 /* 1085 * XXX We could save a lock/unlock if this was only 1086 * enabled under INVARIANTS 1087 */ 1088 BO_LOCK(bo); 1089 if (bo->bo_numoutput > 0 || bo->bo_dirty.bv_cnt > 0) 1090 panic("vinvalbuf: dirty bufs"); 1091 } 1092 } 1093 /* 1094 * If you alter this loop please notice that interlock is dropped and 1095 * reacquired in flushbuflist. Special care is needed to ensure that 1096 * no race conditions occur from this. 1097 */ 1098 do { 1099 error = flushbuflist(&bo->bo_clean, 1100 flags, bo, slpflag, slptimeo); 1101 if (error == 0) 1102 error = flushbuflist(&bo->bo_dirty, 1103 flags, bo, slpflag, slptimeo); 1104 if (error != 0 && error != EAGAIN) { 1105 BO_UNLOCK(bo); 1106 return (error); 1107 } 1108 } while (error != 0); 1109 1110 /* 1111 * Wait for I/O to complete. XXX needs cleaning up. The vnode can 1112 * have write I/O in-progress but if there is a VM object then the 1113 * VM object can also have read-I/O in-progress. 1114 */ 1115 do { 1116 bufobj_wwait(bo, 0, 0); 1117 BO_UNLOCK(bo); 1118 if (bo->bo_object != NULL) { 1119 VM_OBJECT_LOCK(bo->bo_object); 1120 vm_object_pip_wait(bo->bo_object, "bovlbx"); 1121 VM_OBJECT_UNLOCK(bo->bo_object); 1122 } 1123 BO_LOCK(bo); 1124 } while (bo->bo_numoutput > 0); 1125 BO_UNLOCK(bo); 1126 1127 /* 1128 * Destroy the copy in the VM cache, too. 1129 */ 1130 if (bo->bo_object != NULL) { 1131 VM_OBJECT_LOCK(bo->bo_object); 1132 vm_object_page_remove(bo->bo_object, 0, 0, 1133 (flags & V_SAVE) ? TRUE : FALSE); 1134 VM_OBJECT_UNLOCK(bo->bo_object); 1135 } 1136 1137 #ifdef INVARIANTS 1138 BO_LOCK(bo); 1139 if ((flags & (V_ALT | V_NORMAL)) == 0 && 1140 (bo->bo_dirty.bv_cnt > 0 || bo->bo_clean.bv_cnt > 0)) 1141 panic("vinvalbuf: flush failed"); 1142 BO_UNLOCK(bo); 1143 #endif 1144 return (0); 1145 } 1146 1147 /* 1148 * Flush out and invalidate all buffers associated with a vnode. 1149 * Called with the underlying object locked. 1150 */ 1151 int 1152 vinvalbuf(struct vnode *vp, int flags, struct thread *td, int slpflag, 1153 int slptimeo) 1154 { 1155 1156 CTR2(KTR_VFS, "vinvalbuf vp %p flags %d", vp, flags); 1157 ASSERT_VOP_LOCKED(vp, "vinvalbuf"); 1158 return (bufobj_invalbuf(&vp->v_bufobj, flags, td, slpflag, slptimeo)); 1159 } 1160 1161 /* 1162 * Flush out buffers on the specified list. 1163 * 1164 */ 1165 static int 1166 flushbuflist( struct bufv *bufv, int flags, struct bufobj *bo, int slpflag, 1167 int slptimeo) 1168 { 1169 struct buf *bp, *nbp; 1170 int retval, error; 1171 daddr_t lblkno; 1172 b_xflags_t xflags; 1173 1174 ASSERT_BO_LOCKED(bo); 1175 1176 retval = 0; 1177 TAILQ_FOREACH_SAFE(bp, &bufv->bv_hd, b_bobufs, nbp) { 1178 if (((flags & V_NORMAL) && (bp->b_xflags & BX_ALTDATA)) || 1179 ((flags & V_ALT) && (bp->b_xflags & BX_ALTDATA) == 0)) { 1180 continue; 1181 } 1182 lblkno = 0; 1183 xflags = 0; 1184 if (nbp != NULL) { 1185 lblkno = nbp->b_lblkno; 1186 xflags = nbp->b_xflags & 1187 (BX_BKGRDMARKER | BX_VNDIRTY | BX_VNCLEAN); 1188 } 1189 retval = EAGAIN; 1190 error = BUF_TIMELOCK(bp, 1191 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, BO_MTX(bo), 1192 "flushbuf", slpflag, slptimeo); 1193 if (error) { 1194 BO_LOCK(bo); 1195 return (error != ENOLCK ? error : EAGAIN); 1196 } 1197 KASSERT(bp->b_bufobj == bo, 1198 ("bp %p wrong b_bufobj %p should be %p", 1199 bp, bp->b_bufobj, bo)); 1200 if (bp->b_bufobj != bo) { /* XXX: necessary ? */ 1201 BUF_UNLOCK(bp); 1202 BO_LOCK(bo); 1203 return (EAGAIN); 1204 } 1205 /* 1206 * XXX Since there are no node locks for NFS, I 1207 * believe there is a slight chance that a delayed 1208 * write will occur while sleeping just above, so 1209 * check for it. 1210 */ 1211 if (((bp->b_flags & (B_DELWRI | B_INVAL)) == B_DELWRI) && 1212 (flags & V_SAVE)) { 1213 bremfree(bp); 1214 bp->b_flags |= B_ASYNC; 1215 bwrite(bp); 1216 BO_LOCK(bo); 1217 return (EAGAIN); /* XXX: why not loop ? */ 1218 } 1219 bremfree(bp); 1220 bp->b_flags |= (B_INVAL | B_RELBUF); 1221 bp->b_flags &= ~B_ASYNC; 1222 brelse(bp); 1223 BO_LOCK(bo); 1224 if (nbp != NULL && 1225 (nbp->b_bufobj != bo || 1226 nbp->b_lblkno != lblkno || 1227 (nbp->b_xflags & 1228 (BX_BKGRDMARKER | BX_VNDIRTY | BX_VNCLEAN)) != xflags)) 1229 break; /* nbp invalid */ 1230 } 1231 return (retval); 1232 } 1233 1234 /* 1235 * Truncate a file's buffer and pages to a specified length. This 1236 * is in lieu of the old vinvalbuf mechanism, which performed unneeded 1237 * sync activity. 1238 */ 1239 int 1240 vtruncbuf(struct vnode *vp, struct ucred *cred, struct thread *td, 1241 off_t length, int blksize) 1242 { 1243 struct buf *bp, *nbp; 1244 int anyfreed; 1245 int trunclbn; 1246 struct bufobj *bo; 1247 1248 CTR2(KTR_VFS, "vtruncbuf vp %p length %jd", vp, length); 1249 /* 1250 * Round up to the *next* lbn. 1251 */ 1252 trunclbn = (length + blksize - 1) / blksize; 1253 1254 ASSERT_VOP_LOCKED(vp, "vtruncbuf"); 1255 restart: 1256 bo = &vp->v_bufobj; 1257 BO_LOCK(bo); 1258 anyfreed = 1; 1259 for (;anyfreed;) { 1260 anyfreed = 0; 1261 TAILQ_FOREACH_SAFE(bp, &bo->bo_clean.bv_hd, b_bobufs, nbp) { 1262 if (bp->b_lblkno < trunclbn) 1263 continue; 1264 if (BUF_LOCK(bp, 1265 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, 1266 BO_MTX(bo)) == ENOLCK) 1267 goto restart; 1268 1269 bremfree(bp); 1270 bp->b_flags |= (B_INVAL | B_RELBUF); 1271 bp->b_flags &= ~B_ASYNC; 1272 brelse(bp); 1273 anyfreed = 1; 1274 1275 if (nbp != NULL && 1276 (((nbp->b_xflags & BX_VNCLEAN) == 0) || 1277 (nbp->b_vp != vp) || 1278 (nbp->b_flags & B_DELWRI))) { 1279 goto restart; 1280 } 1281 BO_LOCK(bo); 1282 } 1283 1284 TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) { 1285 if (bp->b_lblkno < trunclbn) 1286 continue; 1287 if (BUF_LOCK(bp, 1288 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, 1289 BO_MTX(bo)) == ENOLCK) 1290 goto restart; 1291 bremfree(bp); 1292 bp->b_flags |= (B_INVAL | B_RELBUF); 1293 bp->b_flags &= ~B_ASYNC; 1294 brelse(bp); 1295 anyfreed = 1; 1296 if (nbp != NULL && 1297 (((nbp->b_xflags & BX_VNDIRTY) == 0) || 1298 (nbp->b_vp != vp) || 1299 (nbp->b_flags & B_DELWRI) == 0)) { 1300 goto restart; 1301 } 1302 BO_LOCK(bo); 1303 } 1304 } 1305 1306 if (length > 0) { 1307 restartsync: 1308 TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) { 1309 if (bp->b_lblkno > 0) 1310 continue; 1311 /* 1312 * Since we hold the vnode lock this should only 1313 * fail if we're racing with the buf daemon. 1314 */ 1315 if (BUF_LOCK(bp, 1316 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, 1317 BO_MTX(bo)) == ENOLCK) { 1318 goto restart; 1319 } 1320 VNASSERT((bp->b_flags & B_DELWRI), vp, 1321 ("buf(%p) on dirty queue without DELWRI", bp)); 1322 1323 bremfree(bp); 1324 bawrite(bp); 1325 BO_LOCK(bo); 1326 goto restartsync; 1327 } 1328 } 1329 1330 bufobj_wwait(bo, 0, 0); 1331 BO_UNLOCK(bo); 1332 vnode_pager_setsize(vp, length); 1333 1334 return (0); 1335 } 1336 1337 /* 1338 * buf_splay() - splay tree core for the clean/dirty list of buffers in 1339 * a vnode. 1340 * 1341 * NOTE: We have to deal with the special case of a background bitmap 1342 * buffer, a situation where two buffers will have the same logical 1343 * block offset. We want (1) only the foreground buffer to be accessed 1344 * in a lookup and (2) must differentiate between the foreground and 1345 * background buffer in the splay tree algorithm because the splay 1346 * tree cannot normally handle multiple entities with the same 'index'. 1347 * We accomplish this by adding differentiating flags to the splay tree's 1348 * numerical domain. 1349 */ 1350 static 1351 struct buf * 1352 buf_splay(daddr_t lblkno, b_xflags_t xflags, struct buf *root) 1353 { 1354 struct buf dummy; 1355 struct buf *lefttreemax, *righttreemin, *y; 1356 1357 if (root == NULL) 1358 return (NULL); 1359 lefttreemax = righttreemin = &dummy; 1360 for (;;) { 1361 if (lblkno < root->b_lblkno || 1362 (lblkno == root->b_lblkno && 1363 (xflags & BX_BKGRDMARKER) < (root->b_xflags & BX_BKGRDMARKER))) { 1364 if ((y = root->b_left) == NULL) 1365 break; 1366 if (lblkno < y->b_lblkno) { 1367 /* Rotate right. */ 1368 root->b_left = y->b_right; 1369 y->b_right = root; 1370 root = y; 1371 if ((y = root->b_left) == NULL) 1372 break; 1373 } 1374 /* Link into the new root's right tree. */ 1375 righttreemin->b_left = root; 1376 righttreemin = root; 1377 } else if (lblkno > root->b_lblkno || 1378 (lblkno == root->b_lblkno && 1379 (xflags & BX_BKGRDMARKER) > (root->b_xflags & BX_BKGRDMARKER))) { 1380 if ((y = root->b_right) == NULL) 1381 break; 1382 if (lblkno > y->b_lblkno) { 1383 /* Rotate left. */ 1384 root->b_right = y->b_left; 1385 y->b_left = root; 1386 root = y; 1387 if ((y = root->b_right) == NULL) 1388 break; 1389 } 1390 /* Link into the new root's left tree. */ 1391 lefttreemax->b_right = root; 1392 lefttreemax = root; 1393 } else { 1394 break; 1395 } 1396 root = y; 1397 } 1398 /* Assemble the new root. */ 1399 lefttreemax->b_right = root->b_left; 1400 righttreemin->b_left = root->b_right; 1401 root->b_left = dummy.b_right; 1402 root->b_right = dummy.b_left; 1403 return (root); 1404 } 1405 1406 static void 1407 buf_vlist_remove(struct buf *bp) 1408 { 1409 struct buf *root; 1410 struct bufv *bv; 1411 1412 KASSERT(bp->b_bufobj != NULL, ("No b_bufobj %p", bp)); 1413 ASSERT_BO_LOCKED(bp->b_bufobj); 1414 KASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) != 1415 (BX_VNDIRTY|BX_VNCLEAN), 1416 ("buf_vlist_remove: Buf %p is on two lists", bp)); 1417 if (bp->b_xflags & BX_VNDIRTY) 1418 bv = &bp->b_bufobj->bo_dirty; 1419 else 1420 bv = &bp->b_bufobj->bo_clean; 1421 if (bp != bv->bv_root) { 1422 root = buf_splay(bp->b_lblkno, bp->b_xflags, bv->bv_root); 1423 KASSERT(root == bp, ("splay lookup failed in remove")); 1424 } 1425 if (bp->b_left == NULL) { 1426 root = bp->b_right; 1427 } else { 1428 root = buf_splay(bp->b_lblkno, bp->b_xflags, bp->b_left); 1429 root->b_right = bp->b_right; 1430 } 1431 bv->bv_root = root; 1432 TAILQ_REMOVE(&bv->bv_hd, bp, b_bobufs); 1433 bv->bv_cnt--; 1434 bp->b_xflags &= ~(BX_VNDIRTY | BX_VNCLEAN); 1435 } 1436 1437 /* 1438 * Add the buffer to the sorted clean or dirty block list using a 1439 * splay tree algorithm. 1440 * 1441 * NOTE: xflags is passed as a constant, optimizing this inline function! 1442 */ 1443 static void 1444 buf_vlist_add(struct buf *bp, struct bufobj *bo, b_xflags_t xflags) 1445 { 1446 struct buf *root; 1447 struct bufv *bv; 1448 1449 ASSERT_BO_LOCKED(bo); 1450 KASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) == 0, 1451 ("buf_vlist_add: Buf %p has existing xflags %d", bp, bp->b_xflags)); 1452 bp->b_xflags |= xflags; 1453 if (xflags & BX_VNDIRTY) 1454 bv = &bo->bo_dirty; 1455 else 1456 bv = &bo->bo_clean; 1457 1458 root = buf_splay(bp->b_lblkno, bp->b_xflags, bv->bv_root); 1459 if (root == NULL) { 1460 bp->b_left = NULL; 1461 bp->b_right = NULL; 1462 TAILQ_INSERT_TAIL(&bv->bv_hd, bp, b_bobufs); 1463 } else if (bp->b_lblkno < root->b_lblkno || 1464 (bp->b_lblkno == root->b_lblkno && 1465 (bp->b_xflags & BX_BKGRDMARKER) < (root->b_xflags & BX_BKGRDMARKER))) { 1466 bp->b_left = root->b_left; 1467 bp->b_right = root; 1468 root->b_left = NULL; 1469 TAILQ_INSERT_BEFORE(root, bp, b_bobufs); 1470 } else { 1471 bp->b_right = root->b_right; 1472 bp->b_left = root; 1473 root->b_right = NULL; 1474 TAILQ_INSERT_AFTER(&bv->bv_hd, root, bp, b_bobufs); 1475 } 1476 bv->bv_cnt++; 1477 bv->bv_root = bp; 1478 } 1479 1480 /* 1481 * Lookup a buffer using the splay tree. Note that we specifically avoid 1482 * shadow buffers used in background bitmap writes. 1483 * 1484 * This code isn't quite efficient as it could be because we are maintaining 1485 * two sorted lists and do not know which list the block resides in. 1486 * 1487 * During a "make buildworld" the desired buffer is found at one of 1488 * the roots more than 60% of the time. Thus, checking both roots 1489 * before performing either splay eliminates unnecessary splays on the 1490 * first tree splayed. 1491 */ 1492 struct buf * 1493 gbincore(struct bufobj *bo, daddr_t lblkno) 1494 { 1495 struct buf *bp; 1496 1497 ASSERT_BO_LOCKED(bo); 1498 if ((bp = bo->bo_clean.bv_root) != NULL && 1499 bp->b_lblkno == lblkno && !(bp->b_xflags & BX_BKGRDMARKER)) 1500 return (bp); 1501 if ((bp = bo->bo_dirty.bv_root) != NULL && 1502 bp->b_lblkno == lblkno && !(bp->b_xflags & BX_BKGRDMARKER)) 1503 return (bp); 1504 if ((bp = bo->bo_clean.bv_root) != NULL) { 1505 bo->bo_clean.bv_root = bp = buf_splay(lblkno, 0, bp); 1506 if (bp->b_lblkno == lblkno && !(bp->b_xflags & BX_BKGRDMARKER)) 1507 return (bp); 1508 } 1509 if ((bp = bo->bo_dirty.bv_root) != NULL) { 1510 bo->bo_dirty.bv_root = bp = buf_splay(lblkno, 0, bp); 1511 if (bp->b_lblkno == lblkno && !(bp->b_xflags & BX_BKGRDMARKER)) 1512 return (bp); 1513 } 1514 return (NULL); 1515 } 1516 1517 /* 1518 * Associate a buffer with a vnode. 1519 */ 1520 void 1521 bgetvp(struct vnode *vp, struct buf *bp) 1522 { 1523 struct bufobj *bo; 1524 1525 bo = &vp->v_bufobj; 1526 ASSERT_BO_LOCKED(bo); 1527 VNASSERT(bp->b_vp == NULL, bp->b_vp, ("bgetvp: not free")); 1528 1529 CTR3(KTR_BUF, "bgetvp(%p) vp %p flags %X", bp, vp, bp->b_flags); 1530 VNASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) == 0, vp, 1531 ("bgetvp: bp already attached! %p", bp)); 1532 1533 vhold(vp); 1534 if (VFS_NEEDSGIANT(vp->v_mount) || bo->bo_flag & BO_NEEDSGIANT) 1535 bp->b_flags |= B_NEEDSGIANT; 1536 bp->b_vp = vp; 1537 bp->b_bufobj = bo; 1538 /* 1539 * Insert onto list for new vnode. 1540 */ 1541 buf_vlist_add(bp, bo, BX_VNCLEAN); 1542 } 1543 1544 /* 1545 * Disassociate a buffer from a vnode. 1546 */ 1547 void 1548 brelvp(struct buf *bp) 1549 { 1550 struct bufobj *bo; 1551 struct vnode *vp; 1552 1553 CTR3(KTR_BUF, "brelvp(%p) vp %p flags %X", bp, bp->b_vp, bp->b_flags); 1554 KASSERT(bp->b_vp != NULL, ("brelvp: NULL")); 1555 1556 /* 1557 * Delete from old vnode list, if on one. 1558 */ 1559 vp = bp->b_vp; /* XXX */ 1560 bo = bp->b_bufobj; 1561 BO_LOCK(bo); 1562 if (bp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN)) 1563 buf_vlist_remove(bp); 1564 else 1565 panic("brelvp: Buffer %p not on queue.", bp); 1566 if ((bo->bo_flag & BO_ONWORKLST) && bo->bo_dirty.bv_cnt == 0) { 1567 bo->bo_flag &= ~BO_ONWORKLST; 1568 mtx_lock(&sync_mtx); 1569 LIST_REMOVE(bo, bo_synclist); 1570 syncer_worklist_len--; 1571 mtx_unlock(&sync_mtx); 1572 } 1573 bp->b_flags &= ~B_NEEDSGIANT; 1574 bp->b_vp = NULL; 1575 bp->b_bufobj = NULL; 1576 BO_UNLOCK(bo); 1577 vdrop(vp); 1578 } 1579 1580 /* 1581 * Add an item to the syncer work queue. 1582 */ 1583 static void 1584 vn_syncer_add_to_worklist(struct bufobj *bo, int delay) 1585 { 1586 int queue, slot; 1587 1588 ASSERT_BO_LOCKED(bo); 1589 1590 mtx_lock(&sync_mtx); 1591 if (bo->bo_flag & BO_ONWORKLST) 1592 LIST_REMOVE(bo, bo_synclist); 1593 else { 1594 bo->bo_flag |= BO_ONWORKLST; 1595 syncer_worklist_len++; 1596 } 1597 1598 if (delay > syncer_maxdelay - 2) 1599 delay = syncer_maxdelay - 2; 1600 slot = (syncer_delayno + delay) & syncer_mask; 1601 1602 queue = VFS_NEEDSGIANT(bo->__bo_vnode->v_mount) ? WI_GIANTQ : 1603 WI_MPSAFEQ; 1604 LIST_INSERT_HEAD(&syncer_workitem_pending[queue][slot], bo, 1605 bo_synclist); 1606 mtx_unlock(&sync_mtx); 1607 } 1608 1609 static int 1610 sysctl_vfs_worklist_len(SYSCTL_HANDLER_ARGS) 1611 { 1612 int error, len; 1613 1614 mtx_lock(&sync_mtx); 1615 len = syncer_worklist_len - sync_vnode_count; 1616 mtx_unlock(&sync_mtx); 1617 error = SYSCTL_OUT(req, &len, sizeof(len)); 1618 return (error); 1619 } 1620 1621 SYSCTL_PROC(_vfs, OID_AUTO, worklist_len, CTLTYPE_INT | CTLFLAG_RD, NULL, 0, 1622 sysctl_vfs_worklist_len, "I", "Syncer thread worklist length"); 1623 1624 static struct proc *updateproc; 1625 static void sched_sync(void); 1626 static struct kproc_desc up_kp = { 1627 "syncer", 1628 sched_sync, 1629 &updateproc 1630 }; 1631 SYSINIT(syncer, SI_SUB_KTHREAD_UPDATE, SI_ORDER_FIRST, kproc_start, &up_kp); 1632 1633 static int 1634 sync_vnode(struct synclist *slp, struct bufobj **bo, struct thread *td) 1635 { 1636 struct vnode *vp; 1637 struct mount *mp; 1638 1639 *bo = LIST_FIRST(slp); 1640 if (*bo == NULL) 1641 return (0); 1642 vp = (*bo)->__bo_vnode; /* XXX */ 1643 if (VOP_ISLOCKED(vp) != 0 || VI_TRYLOCK(vp) == 0) 1644 return (1); 1645 /* 1646 * We use vhold in case the vnode does not 1647 * successfully sync. vhold prevents the vnode from 1648 * going away when we unlock the sync_mtx so that 1649 * we can acquire the vnode interlock. 1650 */ 1651 vholdl(vp); 1652 mtx_unlock(&sync_mtx); 1653 VI_UNLOCK(vp); 1654 if (vn_start_write(vp, &mp, V_NOWAIT) != 0) { 1655 vdrop(vp); 1656 mtx_lock(&sync_mtx); 1657 return (*bo == LIST_FIRST(slp)); 1658 } 1659 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 1660 (void) VOP_FSYNC(vp, MNT_LAZY, td); 1661 VOP_UNLOCK(vp, 0); 1662 vn_finished_write(mp); 1663 BO_LOCK(*bo); 1664 if (((*bo)->bo_flag & BO_ONWORKLST) != 0) { 1665 /* 1666 * Put us back on the worklist. The worklist 1667 * routine will remove us from our current 1668 * position and then add us back in at a later 1669 * position. 1670 */ 1671 vn_syncer_add_to_worklist(*bo, syncdelay); 1672 } 1673 BO_UNLOCK(*bo); 1674 vdrop(vp); 1675 mtx_lock(&sync_mtx); 1676 return (0); 1677 } 1678 1679 /* 1680 * System filesystem synchronizer daemon. 1681 */ 1682 static void 1683 sched_sync(void) 1684 { 1685 struct synclist *gnext, *next; 1686 struct synclist *gslp, *slp; 1687 struct bufobj *bo; 1688 long starttime; 1689 struct thread *td = curthread; 1690 int last_work_seen; 1691 int net_worklist_len; 1692 int syncer_final_iter; 1693 int first_printf; 1694 int error; 1695 1696 last_work_seen = 0; 1697 syncer_final_iter = 0; 1698 first_printf = 1; 1699 syncer_state = SYNCER_RUNNING; 1700 starttime = time_uptime; 1701 td->td_pflags |= TDP_NORUNNINGBUF; 1702 1703 EVENTHANDLER_REGISTER(shutdown_pre_sync, syncer_shutdown, td->td_proc, 1704 SHUTDOWN_PRI_LAST); 1705 1706 mtx_lock(&sync_mtx); 1707 for (;;) { 1708 if (syncer_state == SYNCER_FINAL_DELAY && 1709 syncer_final_iter == 0) { 1710 mtx_unlock(&sync_mtx); 1711 kproc_suspend_check(td->td_proc); 1712 mtx_lock(&sync_mtx); 1713 } 1714 net_worklist_len = syncer_worklist_len - sync_vnode_count; 1715 if (syncer_state != SYNCER_RUNNING && 1716 starttime != time_uptime) { 1717 if (first_printf) { 1718 printf("\nSyncing disks, vnodes remaining..."); 1719 first_printf = 0; 1720 } 1721 printf("%d ", net_worklist_len); 1722 } 1723 starttime = time_uptime; 1724 1725 /* 1726 * Push files whose dirty time has expired. Be careful 1727 * of interrupt race on slp queue. 1728 * 1729 * Skip over empty worklist slots when shutting down. 1730 */ 1731 do { 1732 slp = &syncer_workitem_pending[WI_MPSAFEQ][syncer_delayno]; 1733 gslp = &syncer_workitem_pending[WI_GIANTQ][syncer_delayno]; 1734 syncer_delayno += 1; 1735 if (syncer_delayno == syncer_maxdelay) 1736 syncer_delayno = 0; 1737 next = &syncer_workitem_pending[WI_MPSAFEQ][syncer_delayno]; 1738 gnext = &syncer_workitem_pending[WI_GIANTQ][syncer_delayno]; 1739 /* 1740 * If the worklist has wrapped since the 1741 * it was emptied of all but syncer vnodes, 1742 * switch to the FINAL_DELAY state and run 1743 * for one more second. 1744 */ 1745 if (syncer_state == SYNCER_SHUTTING_DOWN && 1746 net_worklist_len == 0 && 1747 last_work_seen == syncer_delayno) { 1748 syncer_state = SYNCER_FINAL_DELAY; 1749 syncer_final_iter = SYNCER_SHUTDOWN_SPEEDUP; 1750 } 1751 } while (syncer_state != SYNCER_RUNNING && LIST_EMPTY(slp) && 1752 LIST_EMPTY(gslp) && syncer_worklist_len > 0); 1753 1754 /* 1755 * Keep track of the last time there was anything 1756 * on the worklist other than syncer vnodes. 1757 * Return to the SHUTTING_DOWN state if any 1758 * new work appears. 1759 */ 1760 if (net_worklist_len > 0 || syncer_state == SYNCER_RUNNING) 1761 last_work_seen = syncer_delayno; 1762 if (net_worklist_len > 0 && syncer_state == SYNCER_FINAL_DELAY) 1763 syncer_state = SYNCER_SHUTTING_DOWN; 1764 while (!LIST_EMPTY(slp)) { 1765 error = sync_vnode(slp, &bo, td); 1766 if (error == 1) { 1767 LIST_REMOVE(bo, bo_synclist); 1768 LIST_INSERT_HEAD(next, bo, bo_synclist); 1769 continue; 1770 } 1771 } 1772 if (!LIST_EMPTY(gslp)) { 1773 mtx_unlock(&sync_mtx); 1774 mtx_lock(&Giant); 1775 mtx_lock(&sync_mtx); 1776 while (!LIST_EMPTY(gslp)) { 1777 error = sync_vnode(gslp, &bo, td); 1778 if (error == 1) { 1779 LIST_REMOVE(bo, bo_synclist); 1780 LIST_INSERT_HEAD(gnext, bo, 1781 bo_synclist); 1782 continue; 1783 } 1784 } 1785 mtx_unlock(&Giant); 1786 } 1787 if (syncer_state == SYNCER_FINAL_DELAY && syncer_final_iter > 0) 1788 syncer_final_iter--; 1789 /* 1790 * The variable rushjob allows the kernel to speed up the 1791 * processing of the filesystem syncer process. A rushjob 1792 * value of N tells the filesystem syncer to process the next 1793 * N seconds worth of work on its queue ASAP. Currently rushjob 1794 * is used by the soft update code to speed up the filesystem 1795 * syncer process when the incore state is getting so far 1796 * ahead of the disk that the kernel memory pool is being 1797 * threatened with exhaustion. 1798 */ 1799 if (rushjob > 0) { 1800 rushjob -= 1; 1801 continue; 1802 } 1803 /* 1804 * Just sleep for a short period of time between 1805 * iterations when shutting down to allow some I/O 1806 * to happen. 1807 * 1808 * If it has taken us less than a second to process the 1809 * current work, then wait. Otherwise start right over 1810 * again. We can still lose time if any single round 1811 * takes more than two seconds, but it does not really 1812 * matter as we are just trying to generally pace the 1813 * filesystem activity. 1814 */ 1815 if (syncer_state != SYNCER_RUNNING) 1816 cv_timedwait(&sync_wakeup, &sync_mtx, 1817 hz / SYNCER_SHUTDOWN_SPEEDUP); 1818 else if (time_uptime == starttime) 1819 cv_timedwait(&sync_wakeup, &sync_mtx, hz); 1820 } 1821 } 1822 1823 /* 1824 * Request the syncer daemon to speed up its work. 1825 * We never push it to speed up more than half of its 1826 * normal turn time, otherwise it could take over the cpu. 1827 */ 1828 int 1829 speedup_syncer(void) 1830 { 1831 int ret = 0; 1832 1833 mtx_lock(&sync_mtx); 1834 if (rushjob < syncdelay / 2) { 1835 rushjob += 1; 1836 stat_rush_requests += 1; 1837 ret = 1; 1838 } 1839 mtx_unlock(&sync_mtx); 1840 cv_broadcast(&sync_wakeup); 1841 return (ret); 1842 } 1843 1844 /* 1845 * Tell the syncer to speed up its work and run though its work 1846 * list several times, then tell it to shut down. 1847 */ 1848 static void 1849 syncer_shutdown(void *arg, int howto) 1850 { 1851 1852 if (howto & RB_NOSYNC) 1853 return; 1854 mtx_lock(&sync_mtx); 1855 syncer_state = SYNCER_SHUTTING_DOWN; 1856 rushjob = 0; 1857 mtx_unlock(&sync_mtx); 1858 cv_broadcast(&sync_wakeup); 1859 kproc_shutdown(arg, howto); 1860 } 1861 1862 /* 1863 * Reassign a buffer from one vnode to another. 1864 * Used to assign file specific control information 1865 * (indirect blocks) to the vnode to which they belong. 1866 */ 1867 void 1868 reassignbuf(struct buf *bp) 1869 { 1870 struct vnode *vp; 1871 struct bufobj *bo; 1872 int delay; 1873 #ifdef INVARIANTS 1874 struct bufv *bv; 1875 #endif 1876 1877 vp = bp->b_vp; 1878 bo = bp->b_bufobj; 1879 ++reassignbufcalls; 1880 1881 CTR3(KTR_BUF, "reassignbuf(%p) vp %p flags %X", 1882 bp, bp->b_vp, bp->b_flags); 1883 /* 1884 * B_PAGING flagged buffers cannot be reassigned because their vp 1885 * is not fully linked in. 1886 */ 1887 if (bp->b_flags & B_PAGING) 1888 panic("cannot reassign paging buffer"); 1889 1890 /* 1891 * Delete from old vnode list, if on one. 1892 */ 1893 BO_LOCK(bo); 1894 if (bp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN)) 1895 buf_vlist_remove(bp); 1896 else 1897 panic("reassignbuf: Buffer %p not on queue.", bp); 1898 /* 1899 * If dirty, put on list of dirty buffers; otherwise insert onto list 1900 * of clean buffers. 1901 */ 1902 if (bp->b_flags & B_DELWRI) { 1903 if ((bo->bo_flag & BO_ONWORKLST) == 0) { 1904 switch (vp->v_type) { 1905 case VDIR: 1906 delay = dirdelay; 1907 break; 1908 case VCHR: 1909 delay = metadelay; 1910 break; 1911 default: 1912 delay = filedelay; 1913 } 1914 vn_syncer_add_to_worklist(bo, delay); 1915 } 1916 buf_vlist_add(bp, bo, BX_VNDIRTY); 1917 } else { 1918 buf_vlist_add(bp, bo, BX_VNCLEAN); 1919 1920 if ((bo->bo_flag & BO_ONWORKLST) && bo->bo_dirty.bv_cnt == 0) { 1921 mtx_lock(&sync_mtx); 1922 LIST_REMOVE(bo, bo_synclist); 1923 syncer_worklist_len--; 1924 mtx_unlock(&sync_mtx); 1925 bo->bo_flag &= ~BO_ONWORKLST; 1926 } 1927 } 1928 #ifdef INVARIANTS 1929 bv = &bo->bo_clean; 1930 bp = TAILQ_FIRST(&bv->bv_hd); 1931 KASSERT(bp == NULL || bp->b_bufobj == bo, 1932 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 1933 bp = TAILQ_LAST(&bv->bv_hd, buflists); 1934 KASSERT(bp == NULL || bp->b_bufobj == bo, 1935 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 1936 bv = &bo->bo_dirty; 1937 bp = TAILQ_FIRST(&bv->bv_hd); 1938 KASSERT(bp == NULL || bp->b_bufobj == bo, 1939 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 1940 bp = TAILQ_LAST(&bv->bv_hd, buflists); 1941 KASSERT(bp == NULL || bp->b_bufobj == bo, 1942 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 1943 #endif 1944 BO_UNLOCK(bo); 1945 } 1946 1947 /* 1948 * Increment the use and hold counts on the vnode, taking care to reference 1949 * the driver's usecount if this is a chardev. The vholdl() will remove 1950 * the vnode from the free list if it is presently free. Requires the 1951 * vnode interlock and returns with it held. 1952 */ 1953 static void 1954 v_incr_usecount(struct vnode *vp) 1955 { 1956 1957 CTR3(KTR_VFS, "v_incr_usecount: vp %p holdcnt %d usecount %d\n", 1958 vp, vp->v_holdcnt, vp->v_usecount); 1959 vp->v_usecount++; 1960 if (vp->v_type == VCHR && vp->v_rdev != NULL) { 1961 dev_lock(); 1962 vp->v_rdev->si_usecount++; 1963 dev_unlock(); 1964 } 1965 vholdl(vp); 1966 } 1967 1968 /* 1969 * Turn a holdcnt into a use+holdcnt such that only one call to 1970 * v_decr_usecount is needed. 1971 */ 1972 static void 1973 v_upgrade_usecount(struct vnode *vp) 1974 { 1975 1976 CTR3(KTR_VFS, "v_upgrade_usecount: vp %p holdcnt %d usecount %d\n", 1977 vp, vp->v_holdcnt, vp->v_usecount); 1978 vp->v_usecount++; 1979 if (vp->v_type == VCHR && vp->v_rdev != NULL) { 1980 dev_lock(); 1981 vp->v_rdev->si_usecount++; 1982 dev_unlock(); 1983 } 1984 } 1985 1986 /* 1987 * Decrement the vnode use and hold count along with the driver's usecount 1988 * if this is a chardev. The vdropl() below releases the vnode interlock 1989 * as it may free the vnode. 1990 */ 1991 static void 1992 v_decr_usecount(struct vnode *vp) 1993 { 1994 1995 CTR3(KTR_VFS, "v_decr_usecount: vp %p holdcnt %d usecount %d\n", 1996 vp, vp->v_holdcnt, vp->v_usecount); 1997 ASSERT_VI_LOCKED(vp, __FUNCTION__); 1998 VNASSERT(vp->v_usecount > 0, vp, 1999 ("v_decr_usecount: negative usecount")); 2000 vp->v_usecount--; 2001 if (vp->v_type == VCHR && vp->v_rdev != NULL) { 2002 dev_lock(); 2003 vp->v_rdev->si_usecount--; 2004 dev_unlock(); 2005 } 2006 vdropl(vp); 2007 } 2008 2009 /* 2010 * Decrement only the use count and driver use count. This is intended to 2011 * be paired with a follow on vdropl() to release the remaining hold count. 2012 * In this way we may vgone() a vnode with a 0 usecount without risk of 2013 * having it end up on a free list because the hold count is kept above 0. 2014 */ 2015 static void 2016 v_decr_useonly(struct vnode *vp) 2017 { 2018 2019 CTR3(KTR_VFS, "v_decr_useonly: vp %p holdcnt %d usecount %d\n", 2020 vp, vp->v_holdcnt, vp->v_usecount); 2021 ASSERT_VI_LOCKED(vp, __FUNCTION__); 2022 VNASSERT(vp->v_usecount > 0, vp, 2023 ("v_decr_useonly: negative usecount")); 2024 vp->v_usecount--; 2025 if (vp->v_type == VCHR && vp->v_rdev != NULL) { 2026 dev_lock(); 2027 vp->v_rdev->si_usecount--; 2028 dev_unlock(); 2029 } 2030 } 2031 2032 /* 2033 * Grab a particular vnode from the free list, increment its 2034 * reference count and lock it. VI_DOOMED is set if the vnode 2035 * is being destroyed. Only callers who specify LK_RETRY will 2036 * see doomed vnodes. If inactive processing was delayed in 2037 * vput try to do it here. 2038 */ 2039 int 2040 vget(struct vnode *vp, int flags, struct thread *td) 2041 { 2042 int error; 2043 2044 error = 0; 2045 VFS_ASSERT_GIANT(vp->v_mount); 2046 VNASSERT((flags & LK_TYPE_MASK) != 0, vp, 2047 ("vget: invalid lock operation")); 2048 if ((flags & LK_INTERLOCK) == 0) 2049 VI_LOCK(vp); 2050 vholdl(vp); 2051 if ((error = vn_lock(vp, flags | LK_INTERLOCK)) != 0) { 2052 vdrop(vp); 2053 return (error); 2054 } 2055 if (vp->v_iflag & VI_DOOMED && (flags & LK_RETRY) == 0) 2056 panic("vget: vn_lock failed to return ENOENT\n"); 2057 VI_LOCK(vp); 2058 /* Upgrade our holdcnt to a usecount. */ 2059 v_upgrade_usecount(vp); 2060 /* 2061 * We don't guarantee that any particular close will 2062 * trigger inactive processing so just make a best effort 2063 * here at preventing a reference to a removed file. If 2064 * we don't succeed no harm is done. 2065 */ 2066 if (vp->v_iflag & VI_OWEINACT) { 2067 if (VOP_ISLOCKED(vp) == LK_EXCLUSIVE && 2068 (flags & LK_NOWAIT) == 0) 2069 vinactive(vp, td); 2070 vp->v_iflag &= ~VI_OWEINACT; 2071 } 2072 VI_UNLOCK(vp); 2073 return (0); 2074 } 2075 2076 /* 2077 * Increase the reference count of a vnode. 2078 */ 2079 void 2080 vref(struct vnode *vp) 2081 { 2082 2083 VI_LOCK(vp); 2084 v_incr_usecount(vp); 2085 VI_UNLOCK(vp); 2086 } 2087 2088 /* 2089 * Return reference count of a vnode. 2090 * 2091 * The results of this call are only guaranteed when some mechanism other 2092 * than the VI lock is used to stop other processes from gaining references 2093 * to the vnode. This may be the case if the caller holds the only reference. 2094 * This is also useful when stale data is acceptable as race conditions may 2095 * be accounted for by some other means. 2096 */ 2097 int 2098 vrefcnt(struct vnode *vp) 2099 { 2100 int usecnt; 2101 2102 VI_LOCK(vp); 2103 usecnt = vp->v_usecount; 2104 VI_UNLOCK(vp); 2105 2106 return (usecnt); 2107 } 2108 2109 2110 /* 2111 * Vnode put/release. 2112 * If count drops to zero, call inactive routine and return to freelist. 2113 */ 2114 void 2115 vrele(struct vnode *vp) 2116 { 2117 struct thread *td = curthread; /* XXX */ 2118 2119 KASSERT(vp != NULL, ("vrele: null vp")); 2120 VFS_ASSERT_GIANT(vp->v_mount); 2121 2122 VI_LOCK(vp); 2123 2124 /* Skip this v_writecount check if we're going to panic below. */ 2125 VNASSERT(vp->v_writecount < vp->v_usecount || vp->v_usecount < 1, vp, 2126 ("vrele: missed vn_close")); 2127 2128 if (vp->v_usecount > 1 || ((vp->v_iflag & VI_DOINGINACT) && 2129 vp->v_usecount == 1)) { 2130 v_decr_usecount(vp); 2131 return; 2132 } 2133 if (vp->v_usecount != 1) { 2134 #ifdef DIAGNOSTIC 2135 vprint("vrele: negative ref count", vp); 2136 #endif 2137 VI_UNLOCK(vp); 2138 panic("vrele: negative ref cnt"); 2139 } 2140 /* 2141 * We want to hold the vnode until the inactive finishes to 2142 * prevent vgone() races. We drop the use count here and the 2143 * hold count below when we're done. 2144 */ 2145 v_decr_useonly(vp); 2146 /* 2147 * We must call VOP_INACTIVE with the node locked. Mark 2148 * as VI_DOINGINACT to avoid recursion. 2149 */ 2150 vp->v_iflag |= VI_OWEINACT; 2151 if (vn_lock(vp, LK_EXCLUSIVE | LK_INTERLOCK) == 0) { 2152 VI_LOCK(vp); 2153 if (vp->v_usecount > 0) 2154 vp->v_iflag &= ~VI_OWEINACT; 2155 if (vp->v_iflag & VI_OWEINACT) 2156 vinactive(vp, td); 2157 VOP_UNLOCK(vp, 0); 2158 } else { 2159 VI_LOCK(vp); 2160 if (vp->v_usecount > 0) 2161 vp->v_iflag &= ~VI_OWEINACT; 2162 } 2163 vdropl(vp); 2164 } 2165 2166 /* 2167 * Release an already locked vnode. This give the same effects as 2168 * unlock+vrele(), but takes less time and avoids releasing and 2169 * re-aquiring the lock (as vrele() acquires the lock internally.) 2170 */ 2171 void 2172 vput(struct vnode *vp) 2173 { 2174 struct thread *td = curthread; /* XXX */ 2175 int error; 2176 2177 KASSERT(vp != NULL, ("vput: null vp")); 2178 ASSERT_VOP_LOCKED(vp, "vput"); 2179 VFS_ASSERT_GIANT(vp->v_mount); 2180 VI_LOCK(vp); 2181 /* Skip this v_writecount check if we're going to panic below. */ 2182 VNASSERT(vp->v_writecount < vp->v_usecount || vp->v_usecount < 1, vp, 2183 ("vput: missed vn_close")); 2184 error = 0; 2185 2186 if (vp->v_usecount > 1 || ((vp->v_iflag & VI_DOINGINACT) && 2187 vp->v_usecount == 1)) { 2188 VOP_UNLOCK(vp, 0); 2189 v_decr_usecount(vp); 2190 return; 2191 } 2192 2193 if (vp->v_usecount != 1) { 2194 #ifdef DIAGNOSTIC 2195 vprint("vput: negative ref count", vp); 2196 #endif 2197 panic("vput: negative ref cnt"); 2198 } 2199 /* 2200 * We want to hold the vnode until the inactive finishes to 2201 * prevent vgone() races. We drop the use count here and the 2202 * hold count below when we're done. 2203 */ 2204 v_decr_useonly(vp); 2205 vp->v_iflag |= VI_OWEINACT; 2206 if (VOP_ISLOCKED(vp) != LK_EXCLUSIVE) { 2207 error = VOP_LOCK(vp, LK_UPGRADE|LK_INTERLOCK|LK_NOWAIT); 2208 VI_LOCK(vp); 2209 if (error) { 2210 if (vp->v_usecount > 0) 2211 vp->v_iflag &= ~VI_OWEINACT; 2212 goto done; 2213 } 2214 } 2215 if (vp->v_usecount > 0) 2216 vp->v_iflag &= ~VI_OWEINACT; 2217 if (vp->v_iflag & VI_OWEINACT) 2218 vinactive(vp, td); 2219 VOP_UNLOCK(vp, 0); 2220 done: 2221 vdropl(vp); 2222 } 2223 2224 /* 2225 * Somebody doesn't want the vnode recycled. 2226 */ 2227 void 2228 vhold(struct vnode *vp) 2229 { 2230 2231 VI_LOCK(vp); 2232 vholdl(vp); 2233 VI_UNLOCK(vp); 2234 } 2235 2236 void 2237 vholdl(struct vnode *vp) 2238 { 2239 2240 vp->v_holdcnt++; 2241 if (VSHOULDBUSY(vp)) 2242 vbusy(vp); 2243 } 2244 2245 /* 2246 * Note that there is one less who cares about this vnode. vdrop() is the 2247 * opposite of vhold(). 2248 */ 2249 void 2250 vdrop(struct vnode *vp) 2251 { 2252 2253 VI_LOCK(vp); 2254 vdropl(vp); 2255 } 2256 2257 /* 2258 * Drop the hold count of the vnode. If this is the last reference to 2259 * the vnode we will free it if it has been vgone'd otherwise it is 2260 * placed on the free list. 2261 */ 2262 void 2263 vdropl(struct vnode *vp) 2264 { 2265 2266 ASSERT_VI_LOCKED(vp, "vdropl"); 2267 if (vp->v_holdcnt <= 0) 2268 panic("vdrop: holdcnt %d", vp->v_holdcnt); 2269 vp->v_holdcnt--; 2270 if (vp->v_holdcnt == 0) { 2271 if (vp->v_iflag & VI_DOOMED) { 2272 vdestroy(vp); 2273 return; 2274 } else 2275 vfree(vp); 2276 } 2277 VI_UNLOCK(vp); 2278 } 2279 2280 /* 2281 * Call VOP_INACTIVE on the vnode and manage the DOINGINACT and OWEINACT 2282 * flags. DOINGINACT prevents us from recursing in calls to vinactive. 2283 * OWEINACT tracks whether a vnode missed a call to inactive due to a 2284 * failed lock upgrade. 2285 */ 2286 static void 2287 vinactive(struct vnode *vp, struct thread *td) 2288 { 2289 2290 ASSERT_VOP_ELOCKED(vp, "vinactive"); 2291 ASSERT_VI_LOCKED(vp, "vinactive"); 2292 VNASSERT((vp->v_iflag & VI_DOINGINACT) == 0, vp, 2293 ("vinactive: recursed on VI_DOINGINACT")); 2294 vp->v_iflag |= VI_DOINGINACT; 2295 vp->v_iflag &= ~VI_OWEINACT; 2296 VI_UNLOCK(vp); 2297 VOP_INACTIVE(vp, td); 2298 VI_LOCK(vp); 2299 VNASSERT(vp->v_iflag & VI_DOINGINACT, vp, 2300 ("vinactive: lost VI_DOINGINACT")); 2301 vp->v_iflag &= ~VI_DOINGINACT; 2302 } 2303 2304 /* 2305 * Remove any vnodes in the vnode table belonging to mount point mp. 2306 * 2307 * If FORCECLOSE is not specified, there should not be any active ones, 2308 * return error if any are found (nb: this is a user error, not a 2309 * system error). If FORCECLOSE is specified, detach any active vnodes 2310 * that are found. 2311 * 2312 * If WRITECLOSE is set, only flush out regular file vnodes open for 2313 * writing. 2314 * 2315 * SKIPSYSTEM causes any vnodes marked VV_SYSTEM to be skipped. 2316 * 2317 * `rootrefs' specifies the base reference count for the root vnode 2318 * of this filesystem. The root vnode is considered busy if its 2319 * v_usecount exceeds this value. On a successful return, vflush(, td) 2320 * will call vrele() on the root vnode exactly rootrefs times. 2321 * If the SKIPSYSTEM or WRITECLOSE flags are specified, rootrefs must 2322 * be zero. 2323 */ 2324 #ifdef DIAGNOSTIC 2325 static int busyprt = 0; /* print out busy vnodes */ 2326 SYSCTL_INT(_debug, OID_AUTO, busyprt, CTLFLAG_RW, &busyprt, 0, ""); 2327 #endif 2328 2329 int 2330 vflush( struct mount *mp, int rootrefs, int flags, struct thread *td) 2331 { 2332 struct vnode *vp, *mvp, *rootvp = NULL; 2333 struct vattr vattr; 2334 int busy = 0, error; 2335 2336 CTR1(KTR_VFS, "vflush: mp %p", mp); 2337 if (rootrefs > 0) { 2338 KASSERT((flags & (SKIPSYSTEM | WRITECLOSE)) == 0, 2339 ("vflush: bad args")); 2340 /* 2341 * Get the filesystem root vnode. We can vput() it 2342 * immediately, since with rootrefs > 0, it won't go away. 2343 */ 2344 if ((error = VFS_ROOT(mp, LK_EXCLUSIVE, &rootvp, td)) != 0) 2345 return (error); 2346 vput(rootvp); 2347 2348 } 2349 MNT_ILOCK(mp); 2350 loop: 2351 MNT_VNODE_FOREACH(vp, mp, mvp) { 2352 2353 VI_LOCK(vp); 2354 vholdl(vp); 2355 MNT_IUNLOCK(mp); 2356 error = vn_lock(vp, LK_INTERLOCK | LK_EXCLUSIVE); 2357 if (error) { 2358 vdrop(vp); 2359 MNT_ILOCK(mp); 2360 MNT_VNODE_FOREACH_ABORT_ILOCKED(mp, mvp); 2361 goto loop; 2362 } 2363 /* 2364 * Skip over a vnodes marked VV_SYSTEM. 2365 */ 2366 if ((flags & SKIPSYSTEM) && (vp->v_vflag & VV_SYSTEM)) { 2367 VOP_UNLOCK(vp, 0); 2368 vdrop(vp); 2369 MNT_ILOCK(mp); 2370 continue; 2371 } 2372 /* 2373 * If WRITECLOSE is set, flush out unlinked but still open 2374 * files (even if open only for reading) and regular file 2375 * vnodes open for writing. 2376 */ 2377 if (flags & WRITECLOSE) { 2378 error = VOP_GETATTR(vp, &vattr, td->td_ucred); 2379 VI_LOCK(vp); 2380 2381 if ((vp->v_type == VNON || 2382 (error == 0 && vattr.va_nlink > 0)) && 2383 (vp->v_writecount == 0 || vp->v_type != VREG)) { 2384 VOP_UNLOCK(vp, 0); 2385 vdropl(vp); 2386 MNT_ILOCK(mp); 2387 continue; 2388 } 2389 } else 2390 VI_LOCK(vp); 2391 /* 2392 * With v_usecount == 0, all we need to do is clear out the 2393 * vnode data structures and we are done. 2394 * 2395 * If FORCECLOSE is set, forcibly close the vnode. 2396 */ 2397 if (vp->v_usecount == 0 || (flags & FORCECLOSE)) { 2398 VNASSERT(vp->v_usecount == 0 || 2399 (vp->v_type != VCHR && vp->v_type != VBLK), vp, 2400 ("device VNODE %p is FORCECLOSED", vp)); 2401 vgonel(vp); 2402 } else { 2403 busy++; 2404 #ifdef DIAGNOSTIC 2405 if (busyprt) 2406 vprint("vflush: busy vnode", vp); 2407 #endif 2408 } 2409 VOP_UNLOCK(vp, 0); 2410 vdropl(vp); 2411 MNT_ILOCK(mp); 2412 } 2413 MNT_IUNLOCK(mp); 2414 if (rootrefs > 0 && (flags & FORCECLOSE) == 0) { 2415 /* 2416 * If just the root vnode is busy, and if its refcount 2417 * is equal to `rootrefs', then go ahead and kill it. 2418 */ 2419 VI_LOCK(rootvp); 2420 KASSERT(busy > 0, ("vflush: not busy")); 2421 VNASSERT(rootvp->v_usecount >= rootrefs, rootvp, 2422 ("vflush: usecount %d < rootrefs %d", 2423 rootvp->v_usecount, rootrefs)); 2424 if (busy == 1 && rootvp->v_usecount == rootrefs) { 2425 VOP_LOCK(rootvp, LK_EXCLUSIVE|LK_INTERLOCK); 2426 vgone(rootvp); 2427 VOP_UNLOCK(rootvp, 0); 2428 busy = 0; 2429 } else 2430 VI_UNLOCK(rootvp); 2431 } 2432 if (busy) 2433 return (EBUSY); 2434 for (; rootrefs > 0; rootrefs--) 2435 vrele(rootvp); 2436 return (0); 2437 } 2438 2439 /* 2440 * Recycle an unused vnode to the front of the free list. 2441 */ 2442 int 2443 vrecycle(struct vnode *vp, struct thread *td) 2444 { 2445 int recycled; 2446 2447 ASSERT_VOP_ELOCKED(vp, "vrecycle"); 2448 recycled = 0; 2449 VI_LOCK(vp); 2450 if (vp->v_usecount == 0) { 2451 recycled = 1; 2452 vgonel(vp); 2453 } 2454 VI_UNLOCK(vp); 2455 return (recycled); 2456 } 2457 2458 /* 2459 * Eliminate all activity associated with a vnode 2460 * in preparation for reuse. 2461 */ 2462 void 2463 vgone(struct vnode *vp) 2464 { 2465 VI_LOCK(vp); 2466 vgonel(vp); 2467 VI_UNLOCK(vp); 2468 } 2469 2470 /* 2471 * vgone, with the vp interlock held. 2472 */ 2473 void 2474 vgonel(struct vnode *vp) 2475 { 2476 struct thread *td; 2477 int oweinact; 2478 int active; 2479 struct mount *mp; 2480 2481 CTR1(KTR_VFS, "vgonel: vp %p", vp); 2482 ASSERT_VOP_ELOCKED(vp, "vgonel"); 2483 ASSERT_VI_LOCKED(vp, "vgonel"); 2484 VNASSERT(vp->v_holdcnt, vp, 2485 ("vgonel: vp %p has no reference.", vp)); 2486 td = curthread; 2487 2488 /* 2489 * Don't vgonel if we're already doomed. 2490 */ 2491 if (vp->v_iflag & VI_DOOMED) 2492 return; 2493 vp->v_iflag |= VI_DOOMED; 2494 /* 2495 * Check to see if the vnode is in use. If so, we have to call 2496 * VOP_CLOSE() and VOP_INACTIVE(). 2497 */ 2498 active = vp->v_usecount; 2499 oweinact = (vp->v_iflag & VI_OWEINACT); 2500 VI_UNLOCK(vp); 2501 /* 2502 * Clean out any buffers associated with the vnode. 2503 * If the flush fails, just toss the buffers. 2504 */ 2505 mp = NULL; 2506 if (!TAILQ_EMPTY(&vp->v_bufobj.bo_dirty.bv_hd)) 2507 (void) vn_start_secondary_write(vp, &mp, V_WAIT); 2508 if (vinvalbuf(vp, V_SAVE, td, 0, 0) != 0) 2509 vinvalbuf(vp, 0, td, 0, 0); 2510 2511 /* 2512 * If purging an active vnode, it must be closed and 2513 * deactivated before being reclaimed. 2514 */ 2515 if (active) 2516 VOP_CLOSE(vp, FNONBLOCK, NOCRED, td); 2517 if (oweinact || active) { 2518 VI_LOCK(vp); 2519 if ((vp->v_iflag & VI_DOINGINACT) == 0) 2520 vinactive(vp, td); 2521 VI_UNLOCK(vp); 2522 } 2523 /* 2524 * Reclaim the vnode. 2525 */ 2526 if (VOP_RECLAIM(vp, td)) 2527 panic("vgone: cannot reclaim"); 2528 if (mp != NULL) 2529 vn_finished_secondary_write(mp); 2530 VNASSERT(vp->v_object == NULL, vp, 2531 ("vop_reclaim left v_object vp=%p, tag=%s", vp, vp->v_tag)); 2532 /* 2533 * Clear the advisory locks and wake up waiting threads. 2534 */ 2535 lf_purgelocks(vp, &(vp->v_lockf)); 2536 /* 2537 * Delete from old mount point vnode list. 2538 */ 2539 delmntque(vp); 2540 cache_purge(vp); 2541 /* 2542 * Done with purge, reset to the standard lock and invalidate 2543 * the vnode. 2544 */ 2545 VI_LOCK(vp); 2546 vp->v_vnlock = &vp->v_lock; 2547 vp->v_op = &dead_vnodeops; 2548 vp->v_tag = "none"; 2549 vp->v_type = VBAD; 2550 } 2551 2552 /* 2553 * Calculate the total number of references to a special device. 2554 */ 2555 int 2556 vcount(struct vnode *vp) 2557 { 2558 int count; 2559 2560 dev_lock(); 2561 count = vp->v_rdev->si_usecount; 2562 dev_unlock(); 2563 return (count); 2564 } 2565 2566 /* 2567 * Same as above, but using the struct cdev *as argument 2568 */ 2569 int 2570 count_dev(struct cdev *dev) 2571 { 2572 int count; 2573 2574 dev_lock(); 2575 count = dev->si_usecount; 2576 dev_unlock(); 2577 return(count); 2578 } 2579 2580 /* 2581 * Print out a description of a vnode. 2582 */ 2583 static char *typename[] = 2584 {"VNON", "VREG", "VDIR", "VBLK", "VCHR", "VLNK", "VSOCK", "VFIFO", "VBAD", 2585 "VMARKER"}; 2586 2587 void 2588 vn_printf(struct vnode *vp, const char *fmt, ...) 2589 { 2590 va_list ap; 2591 char buf[256], buf2[16]; 2592 u_long flags; 2593 2594 va_start(ap, fmt); 2595 vprintf(fmt, ap); 2596 va_end(ap); 2597 printf("%p: ", (void *)vp); 2598 printf("tag %s, type %s\n", vp->v_tag, typename[vp->v_type]); 2599 printf(" usecount %d, writecount %d, refcount %d mountedhere %p\n", 2600 vp->v_usecount, vp->v_writecount, vp->v_holdcnt, vp->v_mountedhere); 2601 buf[0] = '\0'; 2602 buf[1] = '\0'; 2603 if (vp->v_vflag & VV_ROOT) 2604 strlcat(buf, "|VV_ROOT", sizeof(buf)); 2605 if (vp->v_vflag & VV_ISTTY) 2606 strlcat(buf, "|VV_ISTTY", sizeof(buf)); 2607 if (vp->v_vflag & VV_NOSYNC) 2608 strlcat(buf, "|VV_NOSYNC", sizeof(buf)); 2609 if (vp->v_vflag & VV_CACHEDLABEL) 2610 strlcat(buf, "|VV_CACHEDLABEL", sizeof(buf)); 2611 if (vp->v_vflag & VV_TEXT) 2612 strlcat(buf, "|VV_TEXT", sizeof(buf)); 2613 if (vp->v_vflag & VV_COPYONWRITE) 2614 strlcat(buf, "|VV_COPYONWRITE", sizeof(buf)); 2615 if (vp->v_vflag & VV_SYSTEM) 2616 strlcat(buf, "|VV_SYSTEM", sizeof(buf)); 2617 if (vp->v_vflag & VV_PROCDEP) 2618 strlcat(buf, "|VV_PROCDEP", sizeof(buf)); 2619 if (vp->v_vflag & VV_NOKNOTE) 2620 strlcat(buf, "|VV_NOKNOTE", sizeof(buf)); 2621 if (vp->v_vflag & VV_DELETED) 2622 strlcat(buf, "|VV_DELETED", sizeof(buf)); 2623 if (vp->v_vflag & VV_MD) 2624 strlcat(buf, "|VV_MD", sizeof(buf)); 2625 flags = vp->v_vflag & ~(VV_ROOT | VV_ISTTY | VV_NOSYNC | 2626 VV_CACHEDLABEL | VV_TEXT | VV_COPYONWRITE | VV_SYSTEM | VV_PROCDEP | 2627 VV_NOKNOTE | VV_DELETED | VV_MD); 2628 if (flags != 0) { 2629 snprintf(buf2, sizeof(buf2), "|VV(0x%lx)", flags); 2630 strlcat(buf, buf2, sizeof(buf)); 2631 } 2632 if (vp->v_iflag & VI_MOUNT) 2633 strlcat(buf, "|VI_MOUNT", sizeof(buf)); 2634 if (vp->v_iflag & VI_AGE) 2635 strlcat(buf, "|VI_AGE", sizeof(buf)); 2636 if (vp->v_iflag & VI_DOOMED) 2637 strlcat(buf, "|VI_DOOMED", sizeof(buf)); 2638 if (vp->v_iflag & VI_FREE) 2639 strlcat(buf, "|VI_FREE", sizeof(buf)); 2640 if (vp->v_iflag & VI_OBJDIRTY) 2641 strlcat(buf, "|VI_OBJDIRTY", sizeof(buf)); 2642 if (vp->v_iflag & VI_DOINGINACT) 2643 strlcat(buf, "|VI_DOINGINACT", sizeof(buf)); 2644 if (vp->v_iflag & VI_OWEINACT) 2645 strlcat(buf, "|VI_OWEINACT", sizeof(buf)); 2646 flags = vp->v_iflag & ~(VI_MOUNT | VI_AGE | VI_DOOMED | VI_FREE | 2647 VI_OBJDIRTY | VI_DOINGINACT | VI_OWEINACT); 2648 if (flags != 0) { 2649 snprintf(buf2, sizeof(buf2), "|VI(0x%lx)", flags); 2650 strlcat(buf, buf2, sizeof(buf)); 2651 } 2652 printf(" flags (%s)\n", buf + 1); 2653 if (mtx_owned(VI_MTX(vp))) 2654 printf(" VI_LOCKed"); 2655 if (vp->v_object != NULL) 2656 printf(" v_object %p ref %d pages %d\n", 2657 vp->v_object, vp->v_object->ref_count, 2658 vp->v_object->resident_page_count); 2659 printf(" "); 2660 lockmgr_printinfo(vp->v_vnlock); 2661 printf("\n"); 2662 if (vp->v_data != NULL) 2663 VOP_PRINT(vp); 2664 } 2665 2666 #ifdef DDB 2667 /* 2668 * List all of the locked vnodes in the system. 2669 * Called when debugging the kernel. 2670 */ 2671 DB_SHOW_COMMAND(lockedvnods, lockedvnodes) 2672 { 2673 struct mount *mp, *nmp; 2674 struct vnode *vp; 2675 2676 /* 2677 * Note: because this is DDB, we can't obey the locking semantics 2678 * for these structures, which means we could catch an inconsistent 2679 * state and dereference a nasty pointer. Not much to be done 2680 * about that. 2681 */ 2682 db_printf("Locked vnodes\n"); 2683 for (mp = TAILQ_FIRST(&mountlist); mp != NULL; mp = nmp) { 2684 nmp = TAILQ_NEXT(mp, mnt_list); 2685 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) { 2686 if (vp->v_type != VMARKER && 2687 VOP_ISLOCKED(vp)) 2688 vprint("", vp); 2689 } 2690 nmp = TAILQ_NEXT(mp, mnt_list); 2691 } 2692 } 2693 2694 /* 2695 * Show details about the given vnode. 2696 */ 2697 DB_SHOW_COMMAND(vnode, db_show_vnode) 2698 { 2699 struct vnode *vp; 2700 2701 if (!have_addr) 2702 return; 2703 vp = (struct vnode *)addr; 2704 vn_printf(vp, "vnode "); 2705 } 2706 2707 /* 2708 * Show details about the given mount point. 2709 */ 2710 DB_SHOW_COMMAND(mount, db_show_mount) 2711 { 2712 struct mount *mp; 2713 struct statfs *sp; 2714 struct vnode *vp; 2715 char buf[512]; 2716 u_int flags; 2717 2718 if (!have_addr) { 2719 /* No address given, print short info about all mount points. */ 2720 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 2721 db_printf("%p %s on %s (%s)\n", mp, 2722 mp->mnt_stat.f_mntfromname, 2723 mp->mnt_stat.f_mntonname, 2724 mp->mnt_stat.f_fstypename); 2725 if (db_pager_quit) 2726 break; 2727 } 2728 db_printf("\nMore info: show mount <addr>\n"); 2729 return; 2730 } 2731 2732 mp = (struct mount *)addr; 2733 db_printf("%p %s on %s (%s)\n", mp, mp->mnt_stat.f_mntfromname, 2734 mp->mnt_stat.f_mntonname, mp->mnt_stat.f_fstypename); 2735 2736 buf[0] = '\0'; 2737 flags = mp->mnt_flag; 2738 #define MNT_FLAG(flag) do { \ 2739 if (flags & (flag)) { \ 2740 if (buf[0] != '\0') \ 2741 strlcat(buf, ", ", sizeof(buf)); \ 2742 strlcat(buf, (#flag) + 4, sizeof(buf)); \ 2743 flags &= ~(flag); \ 2744 } \ 2745 } while (0) 2746 MNT_FLAG(MNT_RDONLY); 2747 MNT_FLAG(MNT_SYNCHRONOUS); 2748 MNT_FLAG(MNT_NOEXEC); 2749 MNT_FLAG(MNT_NOSUID); 2750 MNT_FLAG(MNT_UNION); 2751 MNT_FLAG(MNT_ASYNC); 2752 MNT_FLAG(MNT_SUIDDIR); 2753 MNT_FLAG(MNT_SOFTDEP); 2754 MNT_FLAG(MNT_NOSYMFOLLOW); 2755 MNT_FLAG(MNT_GJOURNAL); 2756 MNT_FLAG(MNT_MULTILABEL); 2757 MNT_FLAG(MNT_ACLS); 2758 MNT_FLAG(MNT_NOATIME); 2759 MNT_FLAG(MNT_NOCLUSTERR); 2760 MNT_FLAG(MNT_NOCLUSTERW); 2761 MNT_FLAG(MNT_EXRDONLY); 2762 MNT_FLAG(MNT_EXPORTED); 2763 MNT_FLAG(MNT_DEFEXPORTED); 2764 MNT_FLAG(MNT_EXPORTANON); 2765 MNT_FLAG(MNT_EXKERB); 2766 MNT_FLAG(MNT_EXPUBLIC); 2767 MNT_FLAG(MNT_LOCAL); 2768 MNT_FLAG(MNT_QUOTA); 2769 MNT_FLAG(MNT_ROOTFS); 2770 MNT_FLAG(MNT_USER); 2771 MNT_FLAG(MNT_IGNORE); 2772 MNT_FLAG(MNT_UPDATE); 2773 MNT_FLAG(MNT_DELEXPORT); 2774 MNT_FLAG(MNT_RELOAD); 2775 MNT_FLAG(MNT_FORCE); 2776 MNT_FLAG(MNT_SNAPSHOT); 2777 MNT_FLAG(MNT_BYFSID); 2778 #undef MNT_FLAG 2779 if (flags != 0) { 2780 if (buf[0] != '\0') 2781 strlcat(buf, ", ", sizeof(buf)); 2782 snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf), 2783 "0x%08x", flags); 2784 } 2785 db_printf(" mnt_flag = %s\n", buf); 2786 2787 buf[0] = '\0'; 2788 flags = mp->mnt_kern_flag; 2789 #define MNT_KERN_FLAG(flag) do { \ 2790 if (flags & (flag)) { \ 2791 if (buf[0] != '\0') \ 2792 strlcat(buf, ", ", sizeof(buf)); \ 2793 strlcat(buf, (#flag) + 5, sizeof(buf)); \ 2794 flags &= ~(flag); \ 2795 } \ 2796 } while (0) 2797 MNT_KERN_FLAG(MNTK_UNMOUNTF); 2798 MNT_KERN_FLAG(MNTK_ASYNC); 2799 MNT_KERN_FLAG(MNTK_SOFTDEP); 2800 MNT_KERN_FLAG(MNTK_NOINSMNTQ); 2801 MNT_KERN_FLAG(MNTK_UNMOUNT); 2802 MNT_KERN_FLAG(MNTK_MWAIT); 2803 MNT_KERN_FLAG(MNTK_SUSPEND); 2804 MNT_KERN_FLAG(MNTK_SUSPEND2); 2805 MNT_KERN_FLAG(MNTK_SUSPENDED); 2806 MNT_KERN_FLAG(MNTK_MPSAFE); 2807 MNT_KERN_FLAG(MNTK_NOKNOTE); 2808 MNT_KERN_FLAG(MNTK_LOOKUP_SHARED); 2809 #undef MNT_KERN_FLAG 2810 if (flags != 0) { 2811 if (buf[0] != '\0') 2812 strlcat(buf, ", ", sizeof(buf)); 2813 snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf), 2814 "0x%08x", flags); 2815 } 2816 db_printf(" mnt_kern_flag = %s\n", buf); 2817 2818 sp = &mp->mnt_stat; 2819 db_printf(" mnt_stat = { version=%u type=%u flags=0x%016jx " 2820 "bsize=%ju iosize=%ju blocks=%ju bfree=%ju bavail=%jd files=%ju " 2821 "ffree=%jd syncwrites=%ju asyncwrites=%ju syncreads=%ju " 2822 "asyncreads=%ju namemax=%u owner=%u fsid=[%d, %d] }\n", 2823 (u_int)sp->f_version, (u_int)sp->f_type, (uintmax_t)sp->f_flags, 2824 (uintmax_t)sp->f_bsize, (uintmax_t)sp->f_iosize, 2825 (uintmax_t)sp->f_blocks, (uintmax_t)sp->f_bfree, 2826 (intmax_t)sp->f_bavail, (uintmax_t)sp->f_files, 2827 (intmax_t)sp->f_ffree, (uintmax_t)sp->f_syncwrites, 2828 (uintmax_t)sp->f_asyncwrites, (uintmax_t)sp->f_syncreads, 2829 (uintmax_t)sp->f_asyncreads, (u_int)sp->f_namemax, 2830 (u_int)sp->f_owner, (int)sp->f_fsid.val[0], (int)sp->f_fsid.val[1]); 2831 2832 db_printf(" mnt_cred = { uid=%u ruid=%u", 2833 (u_int)mp->mnt_cred->cr_uid, (u_int)mp->mnt_cred->cr_ruid); 2834 if (mp->mnt_cred->cr_prison != NULL) 2835 db_printf(", jail=%d", mp->mnt_cred->cr_prison->pr_id); 2836 db_printf(" }\n"); 2837 db_printf(" mnt_ref = %d\n", mp->mnt_ref); 2838 db_printf(" mnt_gen = %d\n", mp->mnt_gen); 2839 db_printf(" mnt_nvnodelistsize = %d\n", mp->mnt_nvnodelistsize); 2840 db_printf(" mnt_writeopcount = %d\n", mp->mnt_writeopcount); 2841 db_printf(" mnt_noasync = %u\n", mp->mnt_noasync); 2842 db_printf(" mnt_maxsymlinklen = %d\n", mp->mnt_maxsymlinklen); 2843 db_printf(" mnt_iosize_max = %d\n", mp->mnt_iosize_max); 2844 db_printf(" mnt_hashseed = %u\n", mp->mnt_hashseed); 2845 db_printf(" mnt_markercnt = %d\n", mp->mnt_markercnt); 2846 db_printf(" mnt_holdcnt = %d\n", mp->mnt_holdcnt); 2847 db_printf(" mnt_holdcntwaiters = %d\n", mp->mnt_holdcntwaiters); 2848 db_printf(" mnt_secondary_writes = %d\n", mp->mnt_secondary_writes); 2849 db_printf(" mnt_secondary_accwrites = %d\n", 2850 mp->mnt_secondary_accwrites); 2851 db_printf(" mnt_gjprovider = %s\n", 2852 mp->mnt_gjprovider != NULL ? mp->mnt_gjprovider : "NULL"); 2853 db_printf("\n"); 2854 2855 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) { 2856 if (vp->v_type != VMARKER) { 2857 vn_printf(vp, "vnode "); 2858 if (db_pager_quit) 2859 break; 2860 } 2861 } 2862 } 2863 #endif /* DDB */ 2864 2865 /* 2866 * Fill in a struct xvfsconf based on a struct vfsconf. 2867 */ 2868 static void 2869 vfsconf2x(struct vfsconf *vfsp, struct xvfsconf *xvfsp) 2870 { 2871 2872 strcpy(xvfsp->vfc_name, vfsp->vfc_name); 2873 xvfsp->vfc_typenum = vfsp->vfc_typenum; 2874 xvfsp->vfc_refcount = vfsp->vfc_refcount; 2875 xvfsp->vfc_flags = vfsp->vfc_flags; 2876 /* 2877 * These are unused in userland, we keep them 2878 * to not break binary compatibility. 2879 */ 2880 xvfsp->vfc_vfsops = NULL; 2881 xvfsp->vfc_next = NULL; 2882 } 2883 2884 /* 2885 * Top level filesystem related information gathering. 2886 */ 2887 static int 2888 sysctl_vfs_conflist(SYSCTL_HANDLER_ARGS) 2889 { 2890 struct vfsconf *vfsp; 2891 struct xvfsconf xvfsp; 2892 int error; 2893 2894 error = 0; 2895 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) { 2896 bzero(&xvfsp, sizeof(xvfsp)); 2897 vfsconf2x(vfsp, &xvfsp); 2898 error = SYSCTL_OUT(req, &xvfsp, sizeof xvfsp); 2899 if (error) 2900 break; 2901 } 2902 return (error); 2903 } 2904 2905 SYSCTL_PROC(_vfs, OID_AUTO, conflist, CTLFLAG_RD, NULL, 0, sysctl_vfs_conflist, 2906 "S,xvfsconf", "List of all configured filesystems"); 2907 2908 #ifndef BURN_BRIDGES 2909 static int sysctl_ovfs_conf(SYSCTL_HANDLER_ARGS); 2910 2911 static int 2912 vfs_sysctl(SYSCTL_HANDLER_ARGS) 2913 { 2914 int *name = (int *)arg1 - 1; /* XXX */ 2915 u_int namelen = arg2 + 1; /* XXX */ 2916 struct vfsconf *vfsp; 2917 struct xvfsconf xvfsp; 2918 2919 printf("WARNING: userland calling deprecated sysctl, " 2920 "please rebuild world\n"); 2921 2922 #if 1 || defined(COMPAT_PRELITE2) 2923 /* Resolve ambiguity between VFS_VFSCONF and VFS_GENERIC. */ 2924 if (namelen == 1) 2925 return (sysctl_ovfs_conf(oidp, arg1, arg2, req)); 2926 #endif 2927 2928 switch (name[1]) { 2929 case VFS_MAXTYPENUM: 2930 if (namelen != 2) 2931 return (ENOTDIR); 2932 return (SYSCTL_OUT(req, &maxvfsconf, sizeof(int))); 2933 case VFS_CONF: 2934 if (namelen != 3) 2935 return (ENOTDIR); /* overloaded */ 2936 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) 2937 if (vfsp->vfc_typenum == name[2]) 2938 break; 2939 if (vfsp == NULL) 2940 return (EOPNOTSUPP); 2941 bzero(&xvfsp, sizeof(xvfsp)); 2942 vfsconf2x(vfsp, &xvfsp); 2943 return (SYSCTL_OUT(req, &xvfsp, sizeof(xvfsp))); 2944 } 2945 return (EOPNOTSUPP); 2946 } 2947 2948 static SYSCTL_NODE(_vfs, VFS_GENERIC, generic, CTLFLAG_RD | CTLFLAG_SKIP, 2949 vfs_sysctl, "Generic filesystem"); 2950 2951 #if 1 || defined(COMPAT_PRELITE2) 2952 2953 static int 2954 sysctl_ovfs_conf(SYSCTL_HANDLER_ARGS) 2955 { 2956 int error; 2957 struct vfsconf *vfsp; 2958 struct ovfsconf ovfs; 2959 2960 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) { 2961 bzero(&ovfs, sizeof(ovfs)); 2962 ovfs.vfc_vfsops = vfsp->vfc_vfsops; /* XXX used as flag */ 2963 strcpy(ovfs.vfc_name, vfsp->vfc_name); 2964 ovfs.vfc_index = vfsp->vfc_typenum; 2965 ovfs.vfc_refcount = vfsp->vfc_refcount; 2966 ovfs.vfc_flags = vfsp->vfc_flags; 2967 error = SYSCTL_OUT(req, &ovfs, sizeof ovfs); 2968 if (error) 2969 return error; 2970 } 2971 return 0; 2972 } 2973 2974 #endif /* 1 || COMPAT_PRELITE2 */ 2975 #endif /* !BURN_BRIDGES */ 2976 2977 #define KINFO_VNODESLOP 10 2978 #ifdef notyet 2979 /* 2980 * Dump vnode list (via sysctl). 2981 */ 2982 /* ARGSUSED */ 2983 static int 2984 sysctl_vnode(SYSCTL_HANDLER_ARGS) 2985 { 2986 struct xvnode *xvn; 2987 struct mount *mp; 2988 struct vnode *vp; 2989 int error, len, n; 2990 2991 /* 2992 * Stale numvnodes access is not fatal here. 2993 */ 2994 req->lock = 0; 2995 len = (numvnodes + KINFO_VNODESLOP) * sizeof *xvn; 2996 if (!req->oldptr) 2997 /* Make an estimate */ 2998 return (SYSCTL_OUT(req, 0, len)); 2999 3000 error = sysctl_wire_old_buffer(req, 0); 3001 if (error != 0) 3002 return (error); 3003 xvn = malloc(len, M_TEMP, M_ZERO | M_WAITOK); 3004 n = 0; 3005 mtx_lock(&mountlist_mtx); 3006 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 3007 if (vfs_busy(mp, LK_NOWAIT, &mountlist_mtx)) 3008 continue; 3009 MNT_ILOCK(mp); 3010 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) { 3011 if (n == len) 3012 break; 3013 vref(vp); 3014 xvn[n].xv_size = sizeof *xvn; 3015 xvn[n].xv_vnode = vp; 3016 xvn[n].xv_id = 0; /* XXX compat */ 3017 #define XV_COPY(field) xvn[n].xv_##field = vp->v_##field 3018 XV_COPY(usecount); 3019 XV_COPY(writecount); 3020 XV_COPY(holdcnt); 3021 XV_COPY(mount); 3022 XV_COPY(numoutput); 3023 XV_COPY(type); 3024 #undef XV_COPY 3025 xvn[n].xv_flag = vp->v_vflag; 3026 3027 switch (vp->v_type) { 3028 case VREG: 3029 case VDIR: 3030 case VLNK: 3031 break; 3032 case VBLK: 3033 case VCHR: 3034 if (vp->v_rdev == NULL) { 3035 vrele(vp); 3036 continue; 3037 } 3038 xvn[n].xv_dev = dev2udev(vp->v_rdev); 3039 break; 3040 case VSOCK: 3041 xvn[n].xv_socket = vp->v_socket; 3042 break; 3043 case VFIFO: 3044 xvn[n].xv_fifo = vp->v_fifoinfo; 3045 break; 3046 case VNON: 3047 case VBAD: 3048 default: 3049 /* shouldn't happen? */ 3050 vrele(vp); 3051 continue; 3052 } 3053 vrele(vp); 3054 ++n; 3055 } 3056 MNT_IUNLOCK(mp); 3057 mtx_lock(&mountlist_mtx); 3058 vfs_unbusy(mp); 3059 if (n == len) 3060 break; 3061 } 3062 mtx_unlock(&mountlist_mtx); 3063 3064 error = SYSCTL_OUT(req, xvn, n * sizeof *xvn); 3065 free(xvn, M_TEMP); 3066 return (error); 3067 } 3068 3069 SYSCTL_PROC(_kern, KERN_VNODE, vnode, CTLTYPE_OPAQUE|CTLFLAG_RD, 3070 0, 0, sysctl_vnode, "S,xvnode", ""); 3071 #endif 3072 3073 /* 3074 * Unmount all filesystems. The list is traversed in reverse order 3075 * of mounting to avoid dependencies. 3076 */ 3077 void 3078 vfs_unmountall(void) 3079 { 3080 struct mount *mp; 3081 struct thread *td; 3082 int error; 3083 3084 KASSERT(curthread != NULL, ("vfs_unmountall: NULL curthread")); 3085 td = curthread; 3086 /* 3087 * Since this only runs when rebooting, it is not interlocked. 3088 */ 3089 while(!TAILQ_EMPTY(&mountlist)) { 3090 mp = TAILQ_LAST(&mountlist, mntlist); 3091 error = dounmount(mp, MNT_FORCE, td); 3092 if (error) { 3093 TAILQ_REMOVE(&mountlist, mp, mnt_list); 3094 /* 3095 * XXX: Due to the way in which we mount the root 3096 * file system off of devfs, devfs will generate a 3097 * "busy" warning when we try to unmount it before 3098 * the root. Don't print a warning as a result in 3099 * order to avoid false positive errors that may 3100 * cause needless upset. 3101 */ 3102 if (strcmp(mp->mnt_vfc->vfc_name, "devfs") != 0) { 3103 printf("unmount of %s failed (", 3104 mp->mnt_stat.f_mntonname); 3105 if (error == EBUSY) 3106 printf("BUSY)\n"); 3107 else 3108 printf("%d)\n", error); 3109 } 3110 } else { 3111 /* The unmount has removed mp from the mountlist */ 3112 } 3113 } 3114 } 3115 3116 /* 3117 * perform msync on all vnodes under a mount point 3118 * the mount point must be locked. 3119 */ 3120 void 3121 vfs_msync(struct mount *mp, int flags) 3122 { 3123 struct vnode *vp, *mvp; 3124 struct vm_object *obj; 3125 3126 MNT_ILOCK(mp); 3127 MNT_VNODE_FOREACH(vp, mp, mvp) { 3128 VI_LOCK(vp); 3129 if ((vp->v_iflag & VI_OBJDIRTY) && 3130 (flags == MNT_WAIT || VOP_ISLOCKED(vp) == 0)) { 3131 MNT_IUNLOCK(mp); 3132 if (!vget(vp, 3133 LK_EXCLUSIVE | LK_RETRY | LK_INTERLOCK, 3134 curthread)) { 3135 if (vp->v_vflag & VV_NOSYNC) { /* unlinked */ 3136 vput(vp); 3137 MNT_ILOCK(mp); 3138 continue; 3139 } 3140 3141 obj = vp->v_object; 3142 if (obj != NULL) { 3143 VM_OBJECT_LOCK(obj); 3144 vm_object_page_clean(obj, 0, 0, 3145 flags == MNT_WAIT ? 3146 OBJPC_SYNC : OBJPC_NOSYNC); 3147 VM_OBJECT_UNLOCK(obj); 3148 } 3149 vput(vp); 3150 } 3151 MNT_ILOCK(mp); 3152 } else 3153 VI_UNLOCK(vp); 3154 } 3155 MNT_IUNLOCK(mp); 3156 } 3157 3158 /* 3159 * Mark a vnode as free, putting it up for recycling. 3160 */ 3161 static void 3162 vfree(struct vnode *vp) 3163 { 3164 3165 CTR1(KTR_VFS, "vfree vp %p", vp); 3166 ASSERT_VI_LOCKED(vp, "vfree"); 3167 mtx_lock(&vnode_free_list_mtx); 3168 VNASSERT(vp->v_op != NULL, vp, ("vfree: vnode already reclaimed.")); 3169 VNASSERT((vp->v_iflag & VI_FREE) == 0, vp, ("vnode already free")); 3170 VNASSERT(VSHOULDFREE(vp), vp, ("vfree: freeing when we shouldn't")); 3171 VNASSERT((vp->v_iflag & VI_DOOMED) == 0, vp, 3172 ("vfree: Freeing doomed vnode")); 3173 if (vp->v_iflag & VI_AGE) { 3174 TAILQ_INSERT_HEAD(&vnode_free_list, vp, v_freelist); 3175 } else { 3176 TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_freelist); 3177 } 3178 freevnodes++; 3179 vp->v_iflag &= ~VI_AGE; 3180 vp->v_iflag |= VI_FREE; 3181 mtx_unlock(&vnode_free_list_mtx); 3182 } 3183 3184 /* 3185 * Opposite of vfree() - mark a vnode as in use. 3186 */ 3187 static void 3188 vbusy(struct vnode *vp) 3189 { 3190 CTR1(KTR_VFS, "vbusy vp %p", vp); 3191 ASSERT_VI_LOCKED(vp, "vbusy"); 3192 VNASSERT((vp->v_iflag & VI_FREE) != 0, vp, ("vnode not free")); 3193 VNASSERT(vp->v_op != NULL, vp, ("vbusy: vnode already reclaimed.")); 3194 3195 mtx_lock(&vnode_free_list_mtx); 3196 TAILQ_REMOVE(&vnode_free_list, vp, v_freelist); 3197 freevnodes--; 3198 vp->v_iflag &= ~(VI_FREE|VI_AGE); 3199 mtx_unlock(&vnode_free_list_mtx); 3200 } 3201 3202 /* 3203 * Initalize per-vnode helper structure to hold poll-related state. 3204 */ 3205 void 3206 v_addpollinfo(struct vnode *vp) 3207 { 3208 struct vpollinfo *vi; 3209 3210 vi = uma_zalloc(vnodepoll_zone, M_WAITOK); 3211 if (vp->v_pollinfo != NULL) { 3212 uma_zfree(vnodepoll_zone, vi); 3213 return; 3214 } 3215 vp->v_pollinfo = vi; 3216 mtx_init(&vp->v_pollinfo->vpi_lock, "vnode pollinfo", NULL, MTX_DEF); 3217 knlist_init(&vp->v_pollinfo->vpi_selinfo.si_note, vp, vfs_knllock, 3218 vfs_knlunlock, vfs_knllocked); 3219 } 3220 3221 /* 3222 * Record a process's interest in events which might happen to 3223 * a vnode. Because poll uses the historic select-style interface 3224 * internally, this routine serves as both the ``check for any 3225 * pending events'' and the ``record my interest in future events'' 3226 * functions. (These are done together, while the lock is held, 3227 * to avoid race conditions.) 3228 */ 3229 int 3230 vn_pollrecord(struct vnode *vp, struct thread *td, int events) 3231 { 3232 3233 if (vp->v_pollinfo == NULL) 3234 v_addpollinfo(vp); 3235 mtx_lock(&vp->v_pollinfo->vpi_lock); 3236 if (vp->v_pollinfo->vpi_revents & events) { 3237 /* 3238 * This leaves events we are not interested 3239 * in available for the other process which 3240 * which presumably had requested them 3241 * (otherwise they would never have been 3242 * recorded). 3243 */ 3244 events &= vp->v_pollinfo->vpi_revents; 3245 vp->v_pollinfo->vpi_revents &= ~events; 3246 3247 mtx_unlock(&vp->v_pollinfo->vpi_lock); 3248 return events; 3249 } 3250 vp->v_pollinfo->vpi_events |= events; 3251 selrecord(td, &vp->v_pollinfo->vpi_selinfo); 3252 mtx_unlock(&vp->v_pollinfo->vpi_lock); 3253 return 0; 3254 } 3255 3256 /* 3257 * Routine to create and manage a filesystem syncer vnode. 3258 */ 3259 #define sync_close ((int (*)(struct vop_close_args *))nullop) 3260 static int sync_fsync(struct vop_fsync_args *); 3261 static int sync_inactive(struct vop_inactive_args *); 3262 static int sync_reclaim(struct vop_reclaim_args *); 3263 3264 static struct vop_vector sync_vnodeops = { 3265 .vop_bypass = VOP_EOPNOTSUPP, 3266 .vop_close = sync_close, /* close */ 3267 .vop_fsync = sync_fsync, /* fsync */ 3268 .vop_inactive = sync_inactive, /* inactive */ 3269 .vop_reclaim = sync_reclaim, /* reclaim */ 3270 .vop_lock1 = vop_stdlock, /* lock */ 3271 .vop_unlock = vop_stdunlock, /* unlock */ 3272 .vop_islocked = vop_stdislocked, /* islocked */ 3273 }; 3274 3275 /* 3276 * Create a new filesystem syncer vnode for the specified mount point. 3277 */ 3278 int 3279 vfs_allocate_syncvnode(struct mount *mp) 3280 { 3281 struct vnode *vp; 3282 struct bufobj *bo; 3283 static long start, incr, next; 3284 int error; 3285 3286 /* Allocate a new vnode */ 3287 if ((error = getnewvnode("syncer", mp, &sync_vnodeops, &vp)) != 0) { 3288 mp->mnt_syncer = NULL; 3289 return (error); 3290 } 3291 vp->v_type = VNON; 3292 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 3293 vp->v_vflag |= VV_FORCEINSMQ; 3294 error = insmntque(vp, mp); 3295 if (error != 0) 3296 panic("vfs_allocate_syncvnode: insmntque failed"); 3297 vp->v_vflag &= ~VV_FORCEINSMQ; 3298 VOP_UNLOCK(vp, 0); 3299 /* 3300 * Place the vnode onto the syncer worklist. We attempt to 3301 * scatter them about on the list so that they will go off 3302 * at evenly distributed times even if all the filesystems 3303 * are mounted at once. 3304 */ 3305 next += incr; 3306 if (next == 0 || next > syncer_maxdelay) { 3307 start /= 2; 3308 incr /= 2; 3309 if (start == 0) { 3310 start = syncer_maxdelay / 2; 3311 incr = syncer_maxdelay; 3312 } 3313 next = start; 3314 } 3315 bo = &vp->v_bufobj; 3316 BO_LOCK(bo); 3317 vn_syncer_add_to_worklist(bo, syncdelay > 0 ? next % syncdelay : 0); 3318 /* XXX - vn_syncer_add_to_worklist() also grabs and drops sync_mtx. */ 3319 mtx_lock(&sync_mtx); 3320 sync_vnode_count++; 3321 mtx_unlock(&sync_mtx); 3322 BO_UNLOCK(bo); 3323 mp->mnt_syncer = vp; 3324 return (0); 3325 } 3326 3327 /* 3328 * Do a lazy sync of the filesystem. 3329 */ 3330 static int 3331 sync_fsync(struct vop_fsync_args *ap) 3332 { 3333 struct vnode *syncvp = ap->a_vp; 3334 struct mount *mp = syncvp->v_mount; 3335 int error; 3336 struct bufobj *bo; 3337 3338 /* 3339 * We only need to do something if this is a lazy evaluation. 3340 */ 3341 if (ap->a_waitfor != MNT_LAZY) 3342 return (0); 3343 3344 /* 3345 * Move ourselves to the back of the sync list. 3346 */ 3347 bo = &syncvp->v_bufobj; 3348 BO_LOCK(bo); 3349 vn_syncer_add_to_worklist(bo, syncdelay); 3350 BO_UNLOCK(bo); 3351 3352 /* 3353 * Walk the list of vnodes pushing all that are dirty and 3354 * not already on the sync list. 3355 */ 3356 mtx_lock(&mountlist_mtx); 3357 if (vfs_busy(mp, LK_EXCLUSIVE | LK_NOWAIT, &mountlist_mtx) != 0) { 3358 mtx_unlock(&mountlist_mtx); 3359 return (0); 3360 } 3361 if (vn_start_write(NULL, &mp, V_NOWAIT) != 0) { 3362 vfs_unbusy(mp); 3363 return (0); 3364 } 3365 MNT_ILOCK(mp); 3366 mp->mnt_noasync++; 3367 mp->mnt_kern_flag &= ~MNTK_ASYNC; 3368 MNT_IUNLOCK(mp); 3369 vfs_msync(mp, MNT_NOWAIT); 3370 error = VFS_SYNC(mp, MNT_LAZY, ap->a_td); 3371 MNT_ILOCK(mp); 3372 mp->mnt_noasync--; 3373 if ((mp->mnt_flag & MNT_ASYNC) != 0 && mp->mnt_noasync == 0) 3374 mp->mnt_kern_flag |= MNTK_ASYNC; 3375 MNT_IUNLOCK(mp); 3376 vn_finished_write(mp); 3377 vfs_unbusy(mp); 3378 return (error); 3379 } 3380 3381 /* 3382 * The syncer vnode is no referenced. 3383 */ 3384 static int 3385 sync_inactive(struct vop_inactive_args *ap) 3386 { 3387 3388 vgone(ap->a_vp); 3389 return (0); 3390 } 3391 3392 /* 3393 * The syncer vnode is no longer needed and is being decommissioned. 3394 * 3395 * Modifications to the worklist must be protected by sync_mtx. 3396 */ 3397 static int 3398 sync_reclaim(struct vop_reclaim_args *ap) 3399 { 3400 struct vnode *vp = ap->a_vp; 3401 struct bufobj *bo; 3402 3403 bo = &vp->v_bufobj; 3404 BO_LOCK(bo); 3405 vp->v_mount->mnt_syncer = NULL; 3406 if (bo->bo_flag & BO_ONWORKLST) { 3407 mtx_lock(&sync_mtx); 3408 LIST_REMOVE(bo, bo_synclist); 3409 syncer_worklist_len--; 3410 sync_vnode_count--; 3411 mtx_unlock(&sync_mtx); 3412 bo->bo_flag &= ~BO_ONWORKLST; 3413 } 3414 BO_UNLOCK(bo); 3415 3416 return (0); 3417 } 3418 3419 /* 3420 * Check if vnode represents a disk device 3421 */ 3422 int 3423 vn_isdisk(struct vnode *vp, int *errp) 3424 { 3425 int error; 3426 3427 error = 0; 3428 dev_lock(); 3429 if (vp->v_type != VCHR) 3430 error = ENOTBLK; 3431 else if (vp->v_rdev == NULL) 3432 error = ENXIO; 3433 else if (vp->v_rdev->si_devsw == NULL) 3434 error = ENXIO; 3435 else if (!(vp->v_rdev->si_devsw->d_flags & D_DISK)) 3436 error = ENOTBLK; 3437 dev_unlock(); 3438 if (errp != NULL) 3439 *errp = error; 3440 return (error == 0); 3441 } 3442 3443 /* 3444 * Common filesystem object access control check routine. Accepts a 3445 * vnode's type, "mode", uid and gid, requested access mode, credentials, 3446 * and optional call-by-reference privused argument allowing vaccess() 3447 * to indicate to the caller whether privilege was used to satisfy the 3448 * request (obsoleted). Returns 0 on success, or an errno on failure. 3449 * 3450 * The ifdef'd CAPABILITIES version is here for reference, but is not 3451 * actually used. 3452 */ 3453 int 3454 vaccess(enum vtype type, mode_t file_mode, uid_t file_uid, gid_t file_gid, 3455 mode_t acc_mode, struct ucred *cred, int *privused) 3456 { 3457 mode_t dac_granted; 3458 mode_t priv_granted; 3459 3460 /* 3461 * Look for a normal, non-privileged way to access the file/directory 3462 * as requested. If it exists, go with that. 3463 */ 3464 3465 if (privused != NULL) 3466 *privused = 0; 3467 3468 dac_granted = 0; 3469 3470 /* Check the owner. */ 3471 if (cred->cr_uid == file_uid) { 3472 dac_granted |= VADMIN; 3473 if (file_mode & S_IXUSR) 3474 dac_granted |= VEXEC; 3475 if (file_mode & S_IRUSR) 3476 dac_granted |= VREAD; 3477 if (file_mode & S_IWUSR) 3478 dac_granted |= (VWRITE | VAPPEND); 3479 3480 if ((acc_mode & dac_granted) == acc_mode) 3481 return (0); 3482 3483 goto privcheck; 3484 } 3485 3486 /* Otherwise, check the groups (first match) */ 3487 if (groupmember(file_gid, cred)) { 3488 if (file_mode & S_IXGRP) 3489 dac_granted |= VEXEC; 3490 if (file_mode & S_IRGRP) 3491 dac_granted |= VREAD; 3492 if (file_mode & S_IWGRP) 3493 dac_granted |= (VWRITE | VAPPEND); 3494 3495 if ((acc_mode & dac_granted) == acc_mode) 3496 return (0); 3497 3498 goto privcheck; 3499 } 3500 3501 /* Otherwise, check everyone else. */ 3502 if (file_mode & S_IXOTH) 3503 dac_granted |= VEXEC; 3504 if (file_mode & S_IROTH) 3505 dac_granted |= VREAD; 3506 if (file_mode & S_IWOTH) 3507 dac_granted |= (VWRITE | VAPPEND); 3508 if ((acc_mode & dac_granted) == acc_mode) 3509 return (0); 3510 3511 privcheck: 3512 /* 3513 * Build a privilege mask to determine if the set of privileges 3514 * satisfies the requirements when combined with the granted mask 3515 * from above. For each privilege, if the privilege is required, 3516 * bitwise or the request type onto the priv_granted mask. 3517 */ 3518 priv_granted = 0; 3519 3520 if (type == VDIR) { 3521 /* 3522 * For directories, use PRIV_VFS_LOOKUP to satisfy VEXEC 3523 * requests, instead of PRIV_VFS_EXEC. 3524 */ 3525 if ((acc_mode & VEXEC) && ((dac_granted & VEXEC) == 0) && 3526 !priv_check_cred(cred, PRIV_VFS_LOOKUP, 0)) 3527 priv_granted |= VEXEC; 3528 } else { 3529 if ((acc_mode & VEXEC) && ((dac_granted & VEXEC) == 0) && 3530 !priv_check_cred(cred, PRIV_VFS_EXEC, 0)) 3531 priv_granted |= VEXEC; 3532 } 3533 3534 if ((acc_mode & VREAD) && ((dac_granted & VREAD) == 0) && 3535 !priv_check_cred(cred, PRIV_VFS_READ, 0)) 3536 priv_granted |= VREAD; 3537 3538 if ((acc_mode & VWRITE) && ((dac_granted & VWRITE) == 0) && 3539 !priv_check_cred(cred, PRIV_VFS_WRITE, 0)) 3540 priv_granted |= (VWRITE | VAPPEND); 3541 3542 if ((acc_mode & VADMIN) && ((dac_granted & VADMIN) == 0) && 3543 !priv_check_cred(cred, PRIV_VFS_ADMIN, 0)) 3544 priv_granted |= VADMIN; 3545 3546 if ((acc_mode & (priv_granted | dac_granted)) == acc_mode) { 3547 /* XXX audit: privilege used */ 3548 if (privused != NULL) 3549 *privused = 1; 3550 return (0); 3551 } 3552 3553 return ((acc_mode & VADMIN) ? EPERM : EACCES); 3554 } 3555 3556 /* 3557 * Credential check based on process requesting service, and per-attribute 3558 * permissions. 3559 */ 3560 int 3561 extattr_check_cred(struct vnode *vp, int attrnamespace, struct ucred *cred, 3562 struct thread *td, int access) 3563 { 3564 3565 /* 3566 * Kernel-invoked always succeeds. 3567 */ 3568 if (cred == NOCRED) 3569 return (0); 3570 3571 /* 3572 * Do not allow privileged processes in jail to directly manipulate 3573 * system attributes. 3574 */ 3575 switch (attrnamespace) { 3576 case EXTATTR_NAMESPACE_SYSTEM: 3577 /* Potentially should be: return (EPERM); */ 3578 return (priv_check_cred(cred, PRIV_VFS_EXTATTR_SYSTEM, 0)); 3579 case EXTATTR_NAMESPACE_USER: 3580 return (VOP_ACCESS(vp, access, cred, td)); 3581 default: 3582 return (EPERM); 3583 } 3584 } 3585 3586 #ifdef DEBUG_VFS_LOCKS 3587 /* 3588 * This only exists to supress warnings from unlocked specfs accesses. It is 3589 * no longer ok to have an unlocked VFS. 3590 */ 3591 #define IGNORE_LOCK(vp) (panicstr != NULL || (vp) == NULL || \ 3592 (vp)->v_type == VCHR || (vp)->v_type == VBAD) 3593 3594 int vfs_badlock_ddb = 1; /* Drop into debugger on violation. */ 3595 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_ddb, CTLFLAG_RW, &vfs_badlock_ddb, 0, ""); 3596 3597 int vfs_badlock_mutex = 1; /* Check for interlock across VOPs. */ 3598 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_mutex, CTLFLAG_RW, &vfs_badlock_mutex, 0, ""); 3599 3600 int vfs_badlock_print = 1; /* Print lock violations. */ 3601 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_print, CTLFLAG_RW, &vfs_badlock_print, 0, ""); 3602 3603 #ifdef KDB 3604 int vfs_badlock_backtrace = 1; /* Print backtrace at lock violations. */ 3605 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_backtrace, CTLFLAG_RW, &vfs_badlock_backtrace, 0, ""); 3606 #endif 3607 3608 static void 3609 vfs_badlock(const char *msg, const char *str, struct vnode *vp) 3610 { 3611 3612 #ifdef KDB 3613 if (vfs_badlock_backtrace) 3614 kdb_backtrace(); 3615 #endif 3616 if (vfs_badlock_print) 3617 printf("%s: %p %s\n", str, (void *)vp, msg); 3618 if (vfs_badlock_ddb) 3619 kdb_enter(KDB_WHY_VFSLOCK, "lock violation"); 3620 } 3621 3622 void 3623 assert_vi_locked(struct vnode *vp, const char *str) 3624 { 3625 3626 if (vfs_badlock_mutex && !mtx_owned(VI_MTX(vp))) 3627 vfs_badlock("interlock is not locked but should be", str, vp); 3628 } 3629 3630 void 3631 assert_vi_unlocked(struct vnode *vp, const char *str) 3632 { 3633 3634 if (vfs_badlock_mutex && mtx_owned(VI_MTX(vp))) 3635 vfs_badlock("interlock is locked but should not be", str, vp); 3636 } 3637 3638 void 3639 assert_vop_locked(struct vnode *vp, const char *str) 3640 { 3641 3642 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) == 0) 3643 vfs_badlock("is not locked but should be", str, vp); 3644 } 3645 3646 void 3647 assert_vop_unlocked(struct vnode *vp, const char *str) 3648 { 3649 3650 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) == LK_EXCLUSIVE) 3651 vfs_badlock("is locked but should not be", str, vp); 3652 } 3653 3654 void 3655 assert_vop_elocked(struct vnode *vp, const char *str) 3656 { 3657 3658 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) != LK_EXCLUSIVE) 3659 vfs_badlock("is not exclusive locked but should be", str, vp); 3660 } 3661 3662 #if 0 3663 void 3664 assert_vop_elocked_other(struct vnode *vp, const char *str) 3665 { 3666 3667 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) != LK_EXCLOTHER) 3668 vfs_badlock("is not exclusive locked by another thread", 3669 str, vp); 3670 } 3671 3672 void 3673 assert_vop_slocked(struct vnode *vp, const char *str) 3674 { 3675 3676 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) != LK_SHARED) 3677 vfs_badlock("is not locked shared but should be", str, vp); 3678 } 3679 #endif /* 0 */ 3680 #endif /* DEBUG_VFS_LOCKS */ 3681 3682 void 3683 vop_rename_pre(void *ap) 3684 { 3685 struct vop_rename_args *a = ap; 3686 3687 #ifdef DEBUG_VFS_LOCKS 3688 if (a->a_tvp) 3689 ASSERT_VI_UNLOCKED(a->a_tvp, "VOP_RENAME"); 3690 ASSERT_VI_UNLOCKED(a->a_tdvp, "VOP_RENAME"); 3691 ASSERT_VI_UNLOCKED(a->a_fvp, "VOP_RENAME"); 3692 ASSERT_VI_UNLOCKED(a->a_fdvp, "VOP_RENAME"); 3693 3694 /* Check the source (from). */ 3695 if (a->a_tdvp != a->a_fdvp && a->a_tvp != a->a_fdvp) 3696 ASSERT_VOP_UNLOCKED(a->a_fdvp, "vop_rename: fdvp locked"); 3697 if (a->a_tvp != a->a_fvp) 3698 ASSERT_VOP_UNLOCKED(a->a_fvp, "vop_rename: fvp locked"); 3699 3700 /* Check the target. */ 3701 if (a->a_tvp) 3702 ASSERT_VOP_LOCKED(a->a_tvp, "vop_rename: tvp not locked"); 3703 ASSERT_VOP_LOCKED(a->a_tdvp, "vop_rename: tdvp not locked"); 3704 #endif 3705 if (a->a_tdvp != a->a_fdvp) 3706 vhold(a->a_fdvp); 3707 if (a->a_tvp != a->a_fvp) 3708 vhold(a->a_fvp); 3709 vhold(a->a_tdvp); 3710 if (a->a_tvp) 3711 vhold(a->a_tvp); 3712 } 3713 3714 void 3715 vop_strategy_pre(void *ap) 3716 { 3717 #ifdef DEBUG_VFS_LOCKS 3718 struct vop_strategy_args *a; 3719 struct buf *bp; 3720 3721 a = ap; 3722 bp = a->a_bp; 3723 3724 /* 3725 * Cluster ops lock their component buffers but not the IO container. 3726 */ 3727 if ((bp->b_flags & B_CLUSTER) != 0) 3728 return; 3729 3730 if (!BUF_ISLOCKED(bp)) { 3731 if (vfs_badlock_print) 3732 printf( 3733 "VOP_STRATEGY: bp is not locked but should be\n"); 3734 if (vfs_badlock_ddb) 3735 kdb_enter(KDB_WHY_VFSLOCK, "lock violation"); 3736 } 3737 #endif 3738 } 3739 3740 void 3741 vop_lookup_pre(void *ap) 3742 { 3743 #ifdef DEBUG_VFS_LOCKS 3744 struct vop_lookup_args *a; 3745 struct vnode *dvp; 3746 3747 a = ap; 3748 dvp = a->a_dvp; 3749 ASSERT_VI_UNLOCKED(dvp, "VOP_LOOKUP"); 3750 ASSERT_VOP_LOCKED(dvp, "VOP_LOOKUP"); 3751 #endif 3752 } 3753 3754 void 3755 vop_lookup_post(void *ap, int rc) 3756 { 3757 #ifdef DEBUG_VFS_LOCKS 3758 struct vop_lookup_args *a; 3759 struct vnode *dvp; 3760 struct vnode *vp; 3761 3762 a = ap; 3763 dvp = a->a_dvp; 3764 vp = *(a->a_vpp); 3765 3766 ASSERT_VI_UNLOCKED(dvp, "VOP_LOOKUP"); 3767 ASSERT_VOP_LOCKED(dvp, "VOP_LOOKUP"); 3768 3769 if (!rc) 3770 ASSERT_VOP_LOCKED(vp, "VOP_LOOKUP (child)"); 3771 #endif 3772 } 3773 3774 void 3775 vop_lock_pre(void *ap) 3776 { 3777 #ifdef DEBUG_VFS_LOCKS 3778 struct vop_lock1_args *a = ap; 3779 3780 if ((a->a_flags & LK_INTERLOCK) == 0) 3781 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_LOCK"); 3782 else 3783 ASSERT_VI_LOCKED(a->a_vp, "VOP_LOCK"); 3784 #endif 3785 } 3786 3787 void 3788 vop_lock_post(void *ap, int rc) 3789 { 3790 #ifdef DEBUG_VFS_LOCKS 3791 struct vop_lock1_args *a = ap; 3792 3793 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_LOCK"); 3794 if (rc == 0) 3795 ASSERT_VOP_LOCKED(a->a_vp, "VOP_LOCK"); 3796 #endif 3797 } 3798 3799 void 3800 vop_unlock_pre(void *ap) 3801 { 3802 #ifdef DEBUG_VFS_LOCKS 3803 struct vop_unlock_args *a = ap; 3804 3805 if (a->a_flags & LK_INTERLOCK) 3806 ASSERT_VI_LOCKED(a->a_vp, "VOP_UNLOCK"); 3807 ASSERT_VOP_LOCKED(a->a_vp, "VOP_UNLOCK"); 3808 #endif 3809 } 3810 3811 void 3812 vop_unlock_post(void *ap, int rc) 3813 { 3814 #ifdef DEBUG_VFS_LOCKS 3815 struct vop_unlock_args *a = ap; 3816 3817 if (a->a_flags & LK_INTERLOCK) 3818 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_UNLOCK"); 3819 #endif 3820 } 3821 3822 void 3823 vop_create_post(void *ap, int rc) 3824 { 3825 struct vop_create_args *a = ap; 3826 3827 if (!rc) 3828 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 3829 } 3830 3831 void 3832 vop_link_post(void *ap, int rc) 3833 { 3834 struct vop_link_args *a = ap; 3835 3836 if (!rc) { 3837 VFS_KNOTE_LOCKED(a->a_vp, NOTE_LINK); 3838 VFS_KNOTE_LOCKED(a->a_tdvp, NOTE_WRITE); 3839 } 3840 } 3841 3842 void 3843 vop_mkdir_post(void *ap, int rc) 3844 { 3845 struct vop_mkdir_args *a = ap; 3846 3847 if (!rc) 3848 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE | NOTE_LINK); 3849 } 3850 3851 void 3852 vop_mknod_post(void *ap, int rc) 3853 { 3854 struct vop_mknod_args *a = ap; 3855 3856 if (!rc) 3857 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 3858 } 3859 3860 void 3861 vop_remove_post(void *ap, int rc) 3862 { 3863 struct vop_remove_args *a = ap; 3864 3865 if (!rc) { 3866 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 3867 VFS_KNOTE_LOCKED(a->a_vp, NOTE_DELETE); 3868 } 3869 } 3870 3871 void 3872 vop_rename_post(void *ap, int rc) 3873 { 3874 struct vop_rename_args *a = ap; 3875 3876 if (!rc) { 3877 VFS_KNOTE_UNLOCKED(a->a_fdvp, NOTE_WRITE); 3878 VFS_KNOTE_UNLOCKED(a->a_tdvp, NOTE_WRITE); 3879 VFS_KNOTE_UNLOCKED(a->a_fvp, NOTE_RENAME); 3880 if (a->a_tvp) 3881 VFS_KNOTE_UNLOCKED(a->a_tvp, NOTE_DELETE); 3882 } 3883 if (a->a_tdvp != a->a_fdvp) 3884 vdrop(a->a_fdvp); 3885 if (a->a_tvp != a->a_fvp) 3886 vdrop(a->a_fvp); 3887 vdrop(a->a_tdvp); 3888 if (a->a_tvp) 3889 vdrop(a->a_tvp); 3890 } 3891 3892 void 3893 vop_rmdir_post(void *ap, int rc) 3894 { 3895 struct vop_rmdir_args *a = ap; 3896 3897 if (!rc) { 3898 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE | NOTE_LINK); 3899 VFS_KNOTE_LOCKED(a->a_vp, NOTE_DELETE); 3900 } 3901 } 3902 3903 void 3904 vop_setattr_post(void *ap, int rc) 3905 { 3906 struct vop_setattr_args *a = ap; 3907 3908 if (!rc) 3909 VFS_KNOTE_LOCKED(a->a_vp, NOTE_ATTRIB); 3910 } 3911 3912 void 3913 vop_symlink_post(void *ap, int rc) 3914 { 3915 struct vop_symlink_args *a = ap; 3916 3917 if (!rc) 3918 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 3919 } 3920 3921 static struct knlist fs_knlist; 3922 3923 static void 3924 vfs_event_init(void *arg) 3925 { 3926 knlist_init(&fs_knlist, NULL, NULL, NULL, NULL); 3927 } 3928 /* XXX - correct order? */ 3929 SYSINIT(vfs_knlist, SI_SUB_VFS, SI_ORDER_ANY, vfs_event_init, NULL); 3930 3931 void 3932 vfs_event_signal(fsid_t *fsid, u_int32_t event, intptr_t data __unused) 3933 { 3934 3935 KNOTE_UNLOCKED(&fs_knlist, event); 3936 } 3937 3938 static int filt_fsattach(struct knote *kn); 3939 static void filt_fsdetach(struct knote *kn); 3940 static int filt_fsevent(struct knote *kn, long hint); 3941 3942 struct filterops fs_filtops = 3943 { 0, filt_fsattach, filt_fsdetach, filt_fsevent }; 3944 3945 static int 3946 filt_fsattach(struct knote *kn) 3947 { 3948 3949 kn->kn_flags |= EV_CLEAR; 3950 knlist_add(&fs_knlist, kn, 0); 3951 return (0); 3952 } 3953 3954 static void 3955 filt_fsdetach(struct knote *kn) 3956 { 3957 3958 knlist_remove(&fs_knlist, kn, 0); 3959 } 3960 3961 static int 3962 filt_fsevent(struct knote *kn, long hint) 3963 { 3964 3965 kn->kn_fflags |= hint; 3966 return (kn->kn_fflags != 0); 3967 } 3968 3969 static int 3970 sysctl_vfs_ctl(SYSCTL_HANDLER_ARGS) 3971 { 3972 struct vfsidctl vc; 3973 int error; 3974 struct mount *mp; 3975 3976 error = SYSCTL_IN(req, &vc, sizeof(vc)); 3977 if (error) 3978 return (error); 3979 if (vc.vc_vers != VFS_CTL_VERS1) 3980 return (EINVAL); 3981 mp = vfs_getvfs(&vc.vc_fsid); 3982 if (mp == NULL) 3983 return (ENOENT); 3984 /* ensure that a specific sysctl goes to the right filesystem. */ 3985 if (strcmp(vc.vc_fstypename, "*") != 0 && 3986 strcmp(vc.vc_fstypename, mp->mnt_vfc->vfc_name) != 0) { 3987 vfs_rel(mp); 3988 return (EINVAL); 3989 } 3990 VCTLTOREQ(&vc, req); 3991 error = VFS_SYSCTL(mp, vc.vc_op, req); 3992 vfs_rel(mp); 3993 return (error); 3994 } 3995 3996 SYSCTL_PROC(_vfs, OID_AUTO, ctl, CTLFLAG_WR, NULL, 0, sysctl_vfs_ctl, "", 3997 "Sysctl by fsid"); 3998 3999 /* 4000 * Function to initialize a va_filerev field sensibly. 4001 * XXX: Wouldn't a random number make a lot more sense ?? 4002 */ 4003 u_quad_t 4004 init_va_filerev(void) 4005 { 4006 struct bintime bt; 4007 4008 getbinuptime(&bt); 4009 return (((u_quad_t)bt.sec << 32LL) | (bt.frac >> 32LL)); 4010 } 4011 4012 static int filt_vfsread(struct knote *kn, long hint); 4013 static int filt_vfswrite(struct knote *kn, long hint); 4014 static int filt_vfsvnode(struct knote *kn, long hint); 4015 static void filt_vfsdetach(struct knote *kn); 4016 static struct filterops vfsread_filtops = 4017 { 1, NULL, filt_vfsdetach, filt_vfsread }; 4018 static struct filterops vfswrite_filtops = 4019 { 1, NULL, filt_vfsdetach, filt_vfswrite }; 4020 static struct filterops vfsvnode_filtops = 4021 { 1, NULL, filt_vfsdetach, filt_vfsvnode }; 4022 4023 static void 4024 vfs_knllock(void *arg) 4025 { 4026 struct vnode *vp = arg; 4027 4028 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 4029 } 4030 4031 static void 4032 vfs_knlunlock(void *arg) 4033 { 4034 struct vnode *vp = arg; 4035 4036 VOP_UNLOCK(vp, 0); 4037 } 4038 4039 static int 4040 vfs_knllocked(void *arg) 4041 { 4042 struct vnode *vp = arg; 4043 4044 return (VOP_ISLOCKED(vp) == LK_EXCLUSIVE); 4045 } 4046 4047 int 4048 vfs_kqfilter(struct vop_kqfilter_args *ap) 4049 { 4050 struct vnode *vp = ap->a_vp; 4051 struct knote *kn = ap->a_kn; 4052 struct knlist *knl; 4053 4054 switch (kn->kn_filter) { 4055 case EVFILT_READ: 4056 kn->kn_fop = &vfsread_filtops; 4057 break; 4058 case EVFILT_WRITE: 4059 kn->kn_fop = &vfswrite_filtops; 4060 break; 4061 case EVFILT_VNODE: 4062 kn->kn_fop = &vfsvnode_filtops; 4063 break; 4064 default: 4065 return (EINVAL); 4066 } 4067 4068 kn->kn_hook = (caddr_t)vp; 4069 4070 if (vp->v_pollinfo == NULL) 4071 v_addpollinfo(vp); 4072 if (vp->v_pollinfo == NULL) 4073 return (ENOMEM); 4074 knl = &vp->v_pollinfo->vpi_selinfo.si_note; 4075 knlist_add(knl, kn, 0); 4076 4077 return (0); 4078 } 4079 4080 /* 4081 * Detach knote from vnode 4082 */ 4083 static void 4084 filt_vfsdetach(struct knote *kn) 4085 { 4086 struct vnode *vp = (struct vnode *)kn->kn_hook; 4087 4088 KASSERT(vp->v_pollinfo != NULL, ("Missing v_pollinfo")); 4089 knlist_remove(&vp->v_pollinfo->vpi_selinfo.si_note, kn, 0); 4090 } 4091 4092 /*ARGSUSED*/ 4093 static int 4094 filt_vfsread(struct knote *kn, long hint) 4095 { 4096 struct vnode *vp = (struct vnode *)kn->kn_hook; 4097 struct vattr va; 4098 4099 /* 4100 * filesystem is gone, so set the EOF flag and schedule 4101 * the knote for deletion. 4102 */ 4103 if (hint == NOTE_REVOKE) { 4104 kn->kn_flags |= (EV_EOF | EV_ONESHOT); 4105 return (1); 4106 } 4107 4108 if (VOP_GETATTR(vp, &va, curthread->td_ucred)) 4109 return (0); 4110 4111 kn->kn_data = va.va_size - kn->kn_fp->f_offset; 4112 return (kn->kn_data != 0); 4113 } 4114 4115 /*ARGSUSED*/ 4116 static int 4117 filt_vfswrite(struct knote *kn, long hint) 4118 { 4119 /* 4120 * filesystem is gone, so set the EOF flag and schedule 4121 * the knote for deletion. 4122 */ 4123 if (hint == NOTE_REVOKE) 4124 kn->kn_flags |= (EV_EOF | EV_ONESHOT); 4125 4126 kn->kn_data = 0; 4127 return (1); 4128 } 4129 4130 static int 4131 filt_vfsvnode(struct knote *kn, long hint) 4132 { 4133 if (kn->kn_sfflags & hint) 4134 kn->kn_fflags |= hint; 4135 if (hint == NOTE_REVOKE) { 4136 kn->kn_flags |= EV_EOF; 4137 return (1); 4138 } 4139 return (kn->kn_fflags != 0); 4140 } 4141 4142 int 4143 vfs_read_dirent(struct vop_readdir_args *ap, struct dirent *dp, off_t off) 4144 { 4145 int error; 4146 4147 if (dp->d_reclen > ap->a_uio->uio_resid) 4148 return (ENAMETOOLONG); 4149 error = uiomove(dp, dp->d_reclen, ap->a_uio); 4150 if (error) { 4151 if (ap->a_ncookies != NULL) { 4152 if (ap->a_cookies != NULL) 4153 free(ap->a_cookies, M_TEMP); 4154 ap->a_cookies = NULL; 4155 *ap->a_ncookies = 0; 4156 } 4157 return (error); 4158 } 4159 if (ap->a_ncookies == NULL) 4160 return (0); 4161 4162 KASSERT(ap->a_cookies, 4163 ("NULL ap->a_cookies value with non-NULL ap->a_ncookies!")); 4164 4165 *ap->a_cookies = realloc(*ap->a_cookies, 4166 (*ap->a_ncookies + 1) * sizeof(u_long), M_TEMP, M_WAITOK | M_ZERO); 4167 (*ap->a_cookies)[*ap->a_ncookies] = off; 4168 return (0); 4169 } 4170 4171 /* 4172 * Mark for update the access time of the file if the filesystem 4173 * supports VA_MARK_ATIME. This functionality is used by execve 4174 * and mmap, so we want to avoid the synchronous I/O implied by 4175 * directly setting va_atime for the sake of efficiency. 4176 */ 4177 void 4178 vfs_mark_atime(struct vnode *vp, struct ucred *cred) 4179 { 4180 struct vattr atimeattr; 4181 4182 if ((vp->v_mount->mnt_flag & (MNT_NOATIME | MNT_RDONLY)) == 0) { 4183 VATTR_NULL(&atimeattr); 4184 atimeattr.va_vaflags |= VA_MARK_ATIME; 4185 (void)VOP_SETATTR(vp, &atimeattr, cred); 4186 } 4187 } 4188