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, int slpflag, int slptimeo) 1069 { 1070 int error; 1071 1072 BO_LOCK(bo); 1073 if (flags & V_SAVE) { 1074 error = bufobj_wwait(bo, slpflag, slptimeo); 1075 if (error) { 1076 BO_UNLOCK(bo); 1077 return (error); 1078 } 1079 if (bo->bo_dirty.bv_cnt > 0) { 1080 BO_UNLOCK(bo); 1081 if ((error = BO_SYNC(bo, MNT_WAIT)) != 0) 1082 return (error); 1083 /* 1084 * XXX We could save a lock/unlock if this was only 1085 * enabled under INVARIANTS 1086 */ 1087 BO_LOCK(bo); 1088 if (bo->bo_numoutput > 0 || bo->bo_dirty.bv_cnt > 0) 1089 panic("vinvalbuf: dirty bufs"); 1090 } 1091 } 1092 /* 1093 * If you alter this loop please notice that interlock is dropped and 1094 * reacquired in flushbuflist. Special care is needed to ensure that 1095 * no race conditions occur from this. 1096 */ 1097 do { 1098 error = flushbuflist(&bo->bo_clean, 1099 flags, bo, slpflag, slptimeo); 1100 if (error == 0) 1101 error = flushbuflist(&bo->bo_dirty, 1102 flags, bo, slpflag, slptimeo); 1103 if (error != 0 && error != EAGAIN) { 1104 BO_UNLOCK(bo); 1105 return (error); 1106 } 1107 } while (error != 0); 1108 1109 /* 1110 * Wait for I/O to complete. XXX needs cleaning up. The vnode can 1111 * have write I/O in-progress but if there is a VM object then the 1112 * VM object can also have read-I/O in-progress. 1113 */ 1114 do { 1115 bufobj_wwait(bo, 0, 0); 1116 BO_UNLOCK(bo); 1117 if (bo->bo_object != NULL) { 1118 VM_OBJECT_LOCK(bo->bo_object); 1119 vm_object_pip_wait(bo->bo_object, "bovlbx"); 1120 VM_OBJECT_UNLOCK(bo->bo_object); 1121 } 1122 BO_LOCK(bo); 1123 } while (bo->bo_numoutput > 0); 1124 BO_UNLOCK(bo); 1125 1126 /* 1127 * Destroy the copy in the VM cache, too. 1128 */ 1129 if (bo->bo_object != NULL) { 1130 VM_OBJECT_LOCK(bo->bo_object); 1131 vm_object_page_remove(bo->bo_object, 0, 0, 1132 (flags & V_SAVE) ? TRUE : FALSE); 1133 VM_OBJECT_UNLOCK(bo->bo_object); 1134 } 1135 1136 #ifdef INVARIANTS 1137 BO_LOCK(bo); 1138 if ((flags & (V_ALT | V_NORMAL)) == 0 && 1139 (bo->bo_dirty.bv_cnt > 0 || bo->bo_clean.bv_cnt > 0)) 1140 panic("vinvalbuf: flush failed"); 1141 BO_UNLOCK(bo); 1142 #endif 1143 return (0); 1144 } 1145 1146 /* 1147 * Flush out and invalidate all buffers associated with a vnode. 1148 * Called with the underlying object locked. 1149 */ 1150 int 1151 vinvalbuf(struct vnode *vp, int flags, int slpflag, int slptimeo) 1152 { 1153 1154 CTR2(KTR_VFS, "vinvalbuf vp %p flags %d", vp, flags); 1155 ASSERT_VOP_LOCKED(vp, "vinvalbuf"); 1156 return (bufobj_invalbuf(&vp->v_bufobj, flags, slpflag, slptimeo)); 1157 } 1158 1159 /* 1160 * Flush out buffers on the specified list. 1161 * 1162 */ 1163 static int 1164 flushbuflist( struct bufv *bufv, int flags, struct bufobj *bo, int slpflag, 1165 int slptimeo) 1166 { 1167 struct buf *bp, *nbp; 1168 int retval, error; 1169 daddr_t lblkno; 1170 b_xflags_t xflags; 1171 1172 ASSERT_BO_LOCKED(bo); 1173 1174 retval = 0; 1175 TAILQ_FOREACH_SAFE(bp, &bufv->bv_hd, b_bobufs, nbp) { 1176 if (((flags & V_NORMAL) && (bp->b_xflags & BX_ALTDATA)) || 1177 ((flags & V_ALT) && (bp->b_xflags & BX_ALTDATA) == 0)) { 1178 continue; 1179 } 1180 lblkno = 0; 1181 xflags = 0; 1182 if (nbp != NULL) { 1183 lblkno = nbp->b_lblkno; 1184 xflags = nbp->b_xflags & 1185 (BX_BKGRDMARKER | BX_VNDIRTY | BX_VNCLEAN); 1186 } 1187 retval = EAGAIN; 1188 error = BUF_TIMELOCK(bp, 1189 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, BO_MTX(bo), 1190 "flushbuf", slpflag, slptimeo); 1191 if (error) { 1192 BO_LOCK(bo); 1193 return (error != ENOLCK ? error : EAGAIN); 1194 } 1195 KASSERT(bp->b_bufobj == bo, 1196 ("bp %p wrong b_bufobj %p should be %p", 1197 bp, bp->b_bufobj, bo)); 1198 if (bp->b_bufobj != bo) { /* XXX: necessary ? */ 1199 BUF_UNLOCK(bp); 1200 BO_LOCK(bo); 1201 return (EAGAIN); 1202 } 1203 /* 1204 * XXX Since there are no node locks for NFS, I 1205 * believe there is a slight chance that a delayed 1206 * write will occur while sleeping just above, so 1207 * check for it. 1208 */ 1209 if (((bp->b_flags & (B_DELWRI | B_INVAL)) == B_DELWRI) && 1210 (flags & V_SAVE)) { 1211 bremfree(bp); 1212 bp->b_flags |= B_ASYNC; 1213 bwrite(bp); 1214 BO_LOCK(bo); 1215 return (EAGAIN); /* XXX: why not loop ? */ 1216 } 1217 bremfree(bp); 1218 bp->b_flags |= (B_INVAL | B_RELBUF); 1219 bp->b_flags &= ~B_ASYNC; 1220 brelse(bp); 1221 BO_LOCK(bo); 1222 if (nbp != NULL && 1223 (nbp->b_bufobj != bo || 1224 nbp->b_lblkno != lblkno || 1225 (nbp->b_xflags & 1226 (BX_BKGRDMARKER | BX_VNDIRTY | BX_VNCLEAN)) != xflags)) 1227 break; /* nbp invalid */ 1228 } 1229 return (retval); 1230 } 1231 1232 /* 1233 * Truncate a file's buffer and pages to a specified length. This 1234 * is in lieu of the old vinvalbuf mechanism, which performed unneeded 1235 * sync activity. 1236 */ 1237 int 1238 vtruncbuf(struct vnode *vp, struct ucred *cred, struct thread *td, 1239 off_t length, int blksize) 1240 { 1241 struct buf *bp, *nbp; 1242 int anyfreed; 1243 int trunclbn; 1244 struct bufobj *bo; 1245 1246 CTR2(KTR_VFS, "vtruncbuf vp %p length %jd", vp, length); 1247 /* 1248 * Round up to the *next* lbn. 1249 */ 1250 trunclbn = (length + blksize - 1) / blksize; 1251 1252 ASSERT_VOP_LOCKED(vp, "vtruncbuf"); 1253 restart: 1254 bo = &vp->v_bufobj; 1255 BO_LOCK(bo); 1256 anyfreed = 1; 1257 for (;anyfreed;) { 1258 anyfreed = 0; 1259 TAILQ_FOREACH_SAFE(bp, &bo->bo_clean.bv_hd, b_bobufs, nbp) { 1260 if (bp->b_lblkno < trunclbn) 1261 continue; 1262 if (BUF_LOCK(bp, 1263 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, 1264 BO_MTX(bo)) == ENOLCK) 1265 goto restart; 1266 1267 bremfree(bp); 1268 bp->b_flags |= (B_INVAL | B_RELBUF); 1269 bp->b_flags &= ~B_ASYNC; 1270 brelse(bp); 1271 anyfreed = 1; 1272 1273 if (nbp != NULL && 1274 (((nbp->b_xflags & BX_VNCLEAN) == 0) || 1275 (nbp->b_vp != vp) || 1276 (nbp->b_flags & B_DELWRI))) { 1277 goto restart; 1278 } 1279 BO_LOCK(bo); 1280 } 1281 1282 TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) { 1283 if (bp->b_lblkno < trunclbn) 1284 continue; 1285 if (BUF_LOCK(bp, 1286 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, 1287 BO_MTX(bo)) == ENOLCK) 1288 goto restart; 1289 bremfree(bp); 1290 bp->b_flags |= (B_INVAL | B_RELBUF); 1291 bp->b_flags &= ~B_ASYNC; 1292 brelse(bp); 1293 anyfreed = 1; 1294 if (nbp != NULL && 1295 (((nbp->b_xflags & BX_VNDIRTY) == 0) || 1296 (nbp->b_vp != vp) || 1297 (nbp->b_flags & B_DELWRI) == 0)) { 1298 goto restart; 1299 } 1300 BO_LOCK(bo); 1301 } 1302 } 1303 1304 if (length > 0) { 1305 restartsync: 1306 TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) { 1307 if (bp->b_lblkno > 0) 1308 continue; 1309 /* 1310 * Since we hold the vnode lock this should only 1311 * fail if we're racing with the buf daemon. 1312 */ 1313 if (BUF_LOCK(bp, 1314 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, 1315 BO_MTX(bo)) == ENOLCK) { 1316 goto restart; 1317 } 1318 VNASSERT((bp->b_flags & B_DELWRI), vp, 1319 ("buf(%p) on dirty queue without DELWRI", bp)); 1320 1321 bremfree(bp); 1322 bawrite(bp); 1323 BO_LOCK(bo); 1324 goto restartsync; 1325 } 1326 } 1327 1328 bufobj_wwait(bo, 0, 0); 1329 BO_UNLOCK(bo); 1330 vnode_pager_setsize(vp, length); 1331 1332 return (0); 1333 } 1334 1335 /* 1336 * buf_splay() - splay tree core for the clean/dirty list of buffers in 1337 * a vnode. 1338 * 1339 * NOTE: We have to deal with the special case of a background bitmap 1340 * buffer, a situation where two buffers will have the same logical 1341 * block offset. We want (1) only the foreground buffer to be accessed 1342 * in a lookup and (2) must differentiate between the foreground and 1343 * background buffer in the splay tree algorithm because the splay 1344 * tree cannot normally handle multiple entities with the same 'index'. 1345 * We accomplish this by adding differentiating flags to the splay tree's 1346 * numerical domain. 1347 */ 1348 static 1349 struct buf * 1350 buf_splay(daddr_t lblkno, b_xflags_t xflags, struct buf *root) 1351 { 1352 struct buf dummy; 1353 struct buf *lefttreemax, *righttreemin, *y; 1354 1355 if (root == NULL) 1356 return (NULL); 1357 lefttreemax = righttreemin = &dummy; 1358 for (;;) { 1359 if (lblkno < root->b_lblkno || 1360 (lblkno == root->b_lblkno && 1361 (xflags & BX_BKGRDMARKER) < (root->b_xflags & BX_BKGRDMARKER))) { 1362 if ((y = root->b_left) == NULL) 1363 break; 1364 if (lblkno < y->b_lblkno) { 1365 /* Rotate right. */ 1366 root->b_left = y->b_right; 1367 y->b_right = root; 1368 root = y; 1369 if ((y = root->b_left) == NULL) 1370 break; 1371 } 1372 /* Link into the new root's right tree. */ 1373 righttreemin->b_left = root; 1374 righttreemin = root; 1375 } else if (lblkno > root->b_lblkno || 1376 (lblkno == root->b_lblkno && 1377 (xflags & BX_BKGRDMARKER) > (root->b_xflags & BX_BKGRDMARKER))) { 1378 if ((y = root->b_right) == NULL) 1379 break; 1380 if (lblkno > y->b_lblkno) { 1381 /* Rotate left. */ 1382 root->b_right = y->b_left; 1383 y->b_left = root; 1384 root = y; 1385 if ((y = root->b_right) == NULL) 1386 break; 1387 } 1388 /* Link into the new root's left tree. */ 1389 lefttreemax->b_right = root; 1390 lefttreemax = root; 1391 } else { 1392 break; 1393 } 1394 root = y; 1395 } 1396 /* Assemble the new root. */ 1397 lefttreemax->b_right = root->b_left; 1398 righttreemin->b_left = root->b_right; 1399 root->b_left = dummy.b_right; 1400 root->b_right = dummy.b_left; 1401 return (root); 1402 } 1403 1404 static void 1405 buf_vlist_remove(struct buf *bp) 1406 { 1407 struct buf *root; 1408 struct bufv *bv; 1409 1410 KASSERT(bp->b_bufobj != NULL, ("No b_bufobj %p", bp)); 1411 ASSERT_BO_LOCKED(bp->b_bufobj); 1412 KASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) != 1413 (BX_VNDIRTY|BX_VNCLEAN), 1414 ("buf_vlist_remove: Buf %p is on two lists", bp)); 1415 if (bp->b_xflags & BX_VNDIRTY) 1416 bv = &bp->b_bufobj->bo_dirty; 1417 else 1418 bv = &bp->b_bufobj->bo_clean; 1419 if (bp != bv->bv_root) { 1420 root = buf_splay(bp->b_lblkno, bp->b_xflags, bv->bv_root); 1421 KASSERT(root == bp, ("splay lookup failed in remove")); 1422 } 1423 if (bp->b_left == NULL) { 1424 root = bp->b_right; 1425 } else { 1426 root = buf_splay(bp->b_lblkno, bp->b_xflags, bp->b_left); 1427 root->b_right = bp->b_right; 1428 } 1429 bv->bv_root = root; 1430 TAILQ_REMOVE(&bv->bv_hd, bp, b_bobufs); 1431 bv->bv_cnt--; 1432 bp->b_xflags &= ~(BX_VNDIRTY | BX_VNCLEAN); 1433 } 1434 1435 /* 1436 * Add the buffer to the sorted clean or dirty block list using a 1437 * splay tree algorithm. 1438 * 1439 * NOTE: xflags is passed as a constant, optimizing this inline function! 1440 */ 1441 static void 1442 buf_vlist_add(struct buf *bp, struct bufobj *bo, b_xflags_t xflags) 1443 { 1444 struct buf *root; 1445 struct bufv *bv; 1446 1447 ASSERT_BO_LOCKED(bo); 1448 KASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) == 0, 1449 ("buf_vlist_add: Buf %p has existing xflags %d", bp, bp->b_xflags)); 1450 bp->b_xflags |= xflags; 1451 if (xflags & BX_VNDIRTY) 1452 bv = &bo->bo_dirty; 1453 else 1454 bv = &bo->bo_clean; 1455 1456 root = buf_splay(bp->b_lblkno, bp->b_xflags, bv->bv_root); 1457 if (root == NULL) { 1458 bp->b_left = NULL; 1459 bp->b_right = NULL; 1460 TAILQ_INSERT_TAIL(&bv->bv_hd, bp, b_bobufs); 1461 } else if (bp->b_lblkno < root->b_lblkno || 1462 (bp->b_lblkno == root->b_lblkno && 1463 (bp->b_xflags & BX_BKGRDMARKER) < (root->b_xflags & BX_BKGRDMARKER))) { 1464 bp->b_left = root->b_left; 1465 bp->b_right = root; 1466 root->b_left = NULL; 1467 TAILQ_INSERT_BEFORE(root, bp, b_bobufs); 1468 } else { 1469 bp->b_right = root->b_right; 1470 bp->b_left = root; 1471 root->b_right = NULL; 1472 TAILQ_INSERT_AFTER(&bv->bv_hd, root, bp, b_bobufs); 1473 } 1474 bv->bv_cnt++; 1475 bv->bv_root = bp; 1476 } 1477 1478 /* 1479 * Lookup a buffer using the splay tree. Note that we specifically avoid 1480 * shadow buffers used in background bitmap writes. 1481 * 1482 * This code isn't quite efficient as it could be because we are maintaining 1483 * two sorted lists and do not know which list the block resides in. 1484 * 1485 * During a "make buildworld" the desired buffer is found at one of 1486 * the roots more than 60% of the time. Thus, checking both roots 1487 * before performing either splay eliminates unnecessary splays on the 1488 * first tree splayed. 1489 */ 1490 struct buf * 1491 gbincore(struct bufobj *bo, daddr_t lblkno) 1492 { 1493 struct buf *bp; 1494 1495 ASSERT_BO_LOCKED(bo); 1496 if ((bp = bo->bo_clean.bv_root) != NULL && 1497 bp->b_lblkno == lblkno && !(bp->b_xflags & BX_BKGRDMARKER)) 1498 return (bp); 1499 if ((bp = bo->bo_dirty.bv_root) != NULL && 1500 bp->b_lblkno == lblkno && !(bp->b_xflags & BX_BKGRDMARKER)) 1501 return (bp); 1502 if ((bp = bo->bo_clean.bv_root) != NULL) { 1503 bo->bo_clean.bv_root = bp = buf_splay(lblkno, 0, bp); 1504 if (bp->b_lblkno == lblkno && !(bp->b_xflags & BX_BKGRDMARKER)) 1505 return (bp); 1506 } 1507 if ((bp = bo->bo_dirty.bv_root) != NULL) { 1508 bo->bo_dirty.bv_root = bp = buf_splay(lblkno, 0, bp); 1509 if (bp->b_lblkno == lblkno && !(bp->b_xflags & BX_BKGRDMARKER)) 1510 return (bp); 1511 } 1512 return (NULL); 1513 } 1514 1515 /* 1516 * Associate a buffer with a vnode. 1517 */ 1518 void 1519 bgetvp(struct vnode *vp, struct buf *bp) 1520 { 1521 struct bufobj *bo; 1522 1523 bo = &vp->v_bufobj; 1524 ASSERT_BO_LOCKED(bo); 1525 VNASSERT(bp->b_vp == NULL, bp->b_vp, ("bgetvp: not free")); 1526 1527 CTR3(KTR_BUF, "bgetvp(%p) vp %p flags %X", bp, vp, bp->b_flags); 1528 VNASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) == 0, vp, 1529 ("bgetvp: bp already attached! %p", bp)); 1530 1531 vhold(vp); 1532 if (VFS_NEEDSGIANT(vp->v_mount) || bo->bo_flag & BO_NEEDSGIANT) 1533 bp->b_flags |= B_NEEDSGIANT; 1534 bp->b_vp = vp; 1535 bp->b_bufobj = bo; 1536 /* 1537 * Insert onto list for new vnode. 1538 */ 1539 buf_vlist_add(bp, bo, BX_VNCLEAN); 1540 } 1541 1542 /* 1543 * Disassociate a buffer from a vnode. 1544 */ 1545 void 1546 brelvp(struct buf *bp) 1547 { 1548 struct bufobj *bo; 1549 struct vnode *vp; 1550 1551 CTR3(KTR_BUF, "brelvp(%p) vp %p flags %X", bp, bp->b_vp, bp->b_flags); 1552 KASSERT(bp->b_vp != NULL, ("brelvp: NULL")); 1553 1554 /* 1555 * Delete from old vnode list, if on one. 1556 */ 1557 vp = bp->b_vp; /* XXX */ 1558 bo = bp->b_bufobj; 1559 BO_LOCK(bo); 1560 if (bp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN)) 1561 buf_vlist_remove(bp); 1562 else 1563 panic("brelvp: Buffer %p not on queue.", bp); 1564 if ((bo->bo_flag & BO_ONWORKLST) && bo->bo_dirty.bv_cnt == 0) { 1565 bo->bo_flag &= ~BO_ONWORKLST; 1566 mtx_lock(&sync_mtx); 1567 LIST_REMOVE(bo, bo_synclist); 1568 syncer_worklist_len--; 1569 mtx_unlock(&sync_mtx); 1570 } 1571 bp->b_flags &= ~B_NEEDSGIANT; 1572 bp->b_vp = NULL; 1573 bp->b_bufobj = NULL; 1574 BO_UNLOCK(bo); 1575 vdrop(vp); 1576 } 1577 1578 /* 1579 * Add an item to the syncer work queue. 1580 */ 1581 static void 1582 vn_syncer_add_to_worklist(struct bufobj *bo, int delay) 1583 { 1584 int queue, slot; 1585 1586 ASSERT_BO_LOCKED(bo); 1587 1588 mtx_lock(&sync_mtx); 1589 if (bo->bo_flag & BO_ONWORKLST) 1590 LIST_REMOVE(bo, bo_synclist); 1591 else { 1592 bo->bo_flag |= BO_ONWORKLST; 1593 syncer_worklist_len++; 1594 } 1595 1596 if (delay > syncer_maxdelay - 2) 1597 delay = syncer_maxdelay - 2; 1598 slot = (syncer_delayno + delay) & syncer_mask; 1599 1600 queue = VFS_NEEDSGIANT(bo->__bo_vnode->v_mount) ? WI_GIANTQ : 1601 WI_MPSAFEQ; 1602 LIST_INSERT_HEAD(&syncer_workitem_pending[queue][slot], bo, 1603 bo_synclist); 1604 mtx_unlock(&sync_mtx); 1605 } 1606 1607 static int 1608 sysctl_vfs_worklist_len(SYSCTL_HANDLER_ARGS) 1609 { 1610 int error, len; 1611 1612 mtx_lock(&sync_mtx); 1613 len = syncer_worklist_len - sync_vnode_count; 1614 mtx_unlock(&sync_mtx); 1615 error = SYSCTL_OUT(req, &len, sizeof(len)); 1616 return (error); 1617 } 1618 1619 SYSCTL_PROC(_vfs, OID_AUTO, worklist_len, CTLTYPE_INT | CTLFLAG_RD, NULL, 0, 1620 sysctl_vfs_worklist_len, "I", "Syncer thread worklist length"); 1621 1622 static struct proc *updateproc; 1623 static void sched_sync(void); 1624 static struct kproc_desc up_kp = { 1625 "syncer", 1626 sched_sync, 1627 &updateproc 1628 }; 1629 SYSINIT(syncer, SI_SUB_KTHREAD_UPDATE, SI_ORDER_FIRST, kproc_start, &up_kp); 1630 1631 static int 1632 sync_vnode(struct synclist *slp, struct bufobj **bo, struct thread *td) 1633 { 1634 struct vnode *vp; 1635 struct mount *mp; 1636 1637 *bo = LIST_FIRST(slp); 1638 if (*bo == NULL) 1639 return (0); 1640 vp = (*bo)->__bo_vnode; /* XXX */ 1641 if (VOP_ISLOCKED(vp) != 0 || VI_TRYLOCK(vp) == 0) 1642 return (1); 1643 /* 1644 * We use vhold in case the vnode does not 1645 * successfully sync. vhold prevents the vnode from 1646 * going away when we unlock the sync_mtx so that 1647 * we can acquire the vnode interlock. 1648 */ 1649 vholdl(vp); 1650 mtx_unlock(&sync_mtx); 1651 VI_UNLOCK(vp); 1652 if (vn_start_write(vp, &mp, V_NOWAIT) != 0) { 1653 vdrop(vp); 1654 mtx_lock(&sync_mtx); 1655 return (*bo == LIST_FIRST(slp)); 1656 } 1657 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 1658 (void) VOP_FSYNC(vp, MNT_LAZY, td); 1659 VOP_UNLOCK(vp, 0); 1660 vn_finished_write(mp); 1661 BO_LOCK(*bo); 1662 if (((*bo)->bo_flag & BO_ONWORKLST) != 0) { 1663 /* 1664 * Put us back on the worklist. The worklist 1665 * routine will remove us from our current 1666 * position and then add us back in at a later 1667 * position. 1668 */ 1669 vn_syncer_add_to_worklist(*bo, syncdelay); 1670 } 1671 BO_UNLOCK(*bo); 1672 vdrop(vp); 1673 mtx_lock(&sync_mtx); 1674 return (0); 1675 } 1676 1677 /* 1678 * System filesystem synchronizer daemon. 1679 */ 1680 static void 1681 sched_sync(void) 1682 { 1683 struct synclist *gnext, *next; 1684 struct synclist *gslp, *slp; 1685 struct bufobj *bo; 1686 long starttime; 1687 struct thread *td = curthread; 1688 int last_work_seen; 1689 int net_worklist_len; 1690 int syncer_final_iter; 1691 int first_printf; 1692 int error; 1693 1694 last_work_seen = 0; 1695 syncer_final_iter = 0; 1696 first_printf = 1; 1697 syncer_state = SYNCER_RUNNING; 1698 starttime = time_uptime; 1699 td->td_pflags |= TDP_NORUNNINGBUF; 1700 1701 EVENTHANDLER_REGISTER(shutdown_pre_sync, syncer_shutdown, td->td_proc, 1702 SHUTDOWN_PRI_LAST); 1703 1704 mtx_lock(&sync_mtx); 1705 for (;;) { 1706 if (syncer_state == SYNCER_FINAL_DELAY && 1707 syncer_final_iter == 0) { 1708 mtx_unlock(&sync_mtx); 1709 kproc_suspend_check(td->td_proc); 1710 mtx_lock(&sync_mtx); 1711 } 1712 net_worklist_len = syncer_worklist_len - sync_vnode_count; 1713 if (syncer_state != SYNCER_RUNNING && 1714 starttime != time_uptime) { 1715 if (first_printf) { 1716 printf("\nSyncing disks, vnodes remaining..."); 1717 first_printf = 0; 1718 } 1719 printf("%d ", net_worklist_len); 1720 } 1721 starttime = time_uptime; 1722 1723 /* 1724 * Push files whose dirty time has expired. Be careful 1725 * of interrupt race on slp queue. 1726 * 1727 * Skip over empty worklist slots when shutting down. 1728 */ 1729 do { 1730 slp = &syncer_workitem_pending[WI_MPSAFEQ][syncer_delayno]; 1731 gslp = &syncer_workitem_pending[WI_GIANTQ][syncer_delayno]; 1732 syncer_delayno += 1; 1733 if (syncer_delayno == syncer_maxdelay) 1734 syncer_delayno = 0; 1735 next = &syncer_workitem_pending[WI_MPSAFEQ][syncer_delayno]; 1736 gnext = &syncer_workitem_pending[WI_GIANTQ][syncer_delayno]; 1737 /* 1738 * If the worklist has wrapped since the 1739 * it was emptied of all but syncer vnodes, 1740 * switch to the FINAL_DELAY state and run 1741 * for one more second. 1742 */ 1743 if (syncer_state == SYNCER_SHUTTING_DOWN && 1744 net_worklist_len == 0 && 1745 last_work_seen == syncer_delayno) { 1746 syncer_state = SYNCER_FINAL_DELAY; 1747 syncer_final_iter = SYNCER_SHUTDOWN_SPEEDUP; 1748 } 1749 } while (syncer_state != SYNCER_RUNNING && LIST_EMPTY(slp) && 1750 LIST_EMPTY(gslp) && syncer_worklist_len > 0); 1751 1752 /* 1753 * Keep track of the last time there was anything 1754 * on the worklist other than syncer vnodes. 1755 * Return to the SHUTTING_DOWN state if any 1756 * new work appears. 1757 */ 1758 if (net_worklist_len > 0 || syncer_state == SYNCER_RUNNING) 1759 last_work_seen = syncer_delayno; 1760 if (net_worklist_len > 0 && syncer_state == SYNCER_FINAL_DELAY) 1761 syncer_state = SYNCER_SHUTTING_DOWN; 1762 while (!LIST_EMPTY(slp)) { 1763 error = sync_vnode(slp, &bo, td); 1764 if (error == 1) { 1765 LIST_REMOVE(bo, bo_synclist); 1766 LIST_INSERT_HEAD(next, bo, bo_synclist); 1767 continue; 1768 } 1769 } 1770 if (!LIST_EMPTY(gslp)) { 1771 mtx_unlock(&sync_mtx); 1772 mtx_lock(&Giant); 1773 mtx_lock(&sync_mtx); 1774 while (!LIST_EMPTY(gslp)) { 1775 error = sync_vnode(gslp, &bo, td); 1776 if (error == 1) { 1777 LIST_REMOVE(bo, bo_synclist); 1778 LIST_INSERT_HEAD(gnext, bo, 1779 bo_synclist); 1780 continue; 1781 } 1782 } 1783 mtx_unlock(&Giant); 1784 } 1785 if (syncer_state == SYNCER_FINAL_DELAY && syncer_final_iter > 0) 1786 syncer_final_iter--; 1787 /* 1788 * The variable rushjob allows the kernel to speed up the 1789 * processing of the filesystem syncer process. A rushjob 1790 * value of N tells the filesystem syncer to process the next 1791 * N seconds worth of work on its queue ASAP. Currently rushjob 1792 * is used by the soft update code to speed up the filesystem 1793 * syncer process when the incore state is getting so far 1794 * ahead of the disk that the kernel memory pool is being 1795 * threatened with exhaustion. 1796 */ 1797 if (rushjob > 0) { 1798 rushjob -= 1; 1799 continue; 1800 } 1801 /* 1802 * Just sleep for a short period of time between 1803 * iterations when shutting down to allow some I/O 1804 * to happen. 1805 * 1806 * If it has taken us less than a second to process the 1807 * current work, then wait. Otherwise start right over 1808 * again. We can still lose time if any single round 1809 * takes more than two seconds, but it does not really 1810 * matter as we are just trying to generally pace the 1811 * filesystem activity. 1812 */ 1813 if (syncer_state != SYNCER_RUNNING) 1814 cv_timedwait(&sync_wakeup, &sync_mtx, 1815 hz / SYNCER_SHUTDOWN_SPEEDUP); 1816 else if (time_uptime == starttime) 1817 cv_timedwait(&sync_wakeup, &sync_mtx, hz); 1818 } 1819 } 1820 1821 /* 1822 * Request the syncer daemon to speed up its work. 1823 * We never push it to speed up more than half of its 1824 * normal turn time, otherwise it could take over the cpu. 1825 */ 1826 int 1827 speedup_syncer(void) 1828 { 1829 int ret = 0; 1830 1831 mtx_lock(&sync_mtx); 1832 if (rushjob < syncdelay / 2) { 1833 rushjob += 1; 1834 stat_rush_requests += 1; 1835 ret = 1; 1836 } 1837 mtx_unlock(&sync_mtx); 1838 cv_broadcast(&sync_wakeup); 1839 return (ret); 1840 } 1841 1842 /* 1843 * Tell the syncer to speed up its work and run though its work 1844 * list several times, then tell it to shut down. 1845 */ 1846 static void 1847 syncer_shutdown(void *arg, int howto) 1848 { 1849 1850 if (howto & RB_NOSYNC) 1851 return; 1852 mtx_lock(&sync_mtx); 1853 syncer_state = SYNCER_SHUTTING_DOWN; 1854 rushjob = 0; 1855 mtx_unlock(&sync_mtx); 1856 cv_broadcast(&sync_wakeup); 1857 kproc_shutdown(arg, howto); 1858 } 1859 1860 /* 1861 * Reassign a buffer from one vnode to another. 1862 * Used to assign file specific control information 1863 * (indirect blocks) to the vnode to which they belong. 1864 */ 1865 void 1866 reassignbuf(struct buf *bp) 1867 { 1868 struct vnode *vp; 1869 struct bufobj *bo; 1870 int delay; 1871 #ifdef INVARIANTS 1872 struct bufv *bv; 1873 #endif 1874 1875 vp = bp->b_vp; 1876 bo = bp->b_bufobj; 1877 ++reassignbufcalls; 1878 1879 CTR3(KTR_BUF, "reassignbuf(%p) vp %p flags %X", 1880 bp, bp->b_vp, bp->b_flags); 1881 /* 1882 * B_PAGING flagged buffers cannot be reassigned because their vp 1883 * is not fully linked in. 1884 */ 1885 if (bp->b_flags & B_PAGING) 1886 panic("cannot reassign paging buffer"); 1887 1888 /* 1889 * Delete from old vnode list, if on one. 1890 */ 1891 BO_LOCK(bo); 1892 if (bp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN)) 1893 buf_vlist_remove(bp); 1894 else 1895 panic("reassignbuf: Buffer %p not on queue.", bp); 1896 /* 1897 * If dirty, put on list of dirty buffers; otherwise insert onto list 1898 * of clean buffers. 1899 */ 1900 if (bp->b_flags & B_DELWRI) { 1901 if ((bo->bo_flag & BO_ONWORKLST) == 0) { 1902 switch (vp->v_type) { 1903 case VDIR: 1904 delay = dirdelay; 1905 break; 1906 case VCHR: 1907 delay = metadelay; 1908 break; 1909 default: 1910 delay = filedelay; 1911 } 1912 vn_syncer_add_to_worklist(bo, delay); 1913 } 1914 buf_vlist_add(bp, bo, BX_VNDIRTY); 1915 } else { 1916 buf_vlist_add(bp, bo, BX_VNCLEAN); 1917 1918 if ((bo->bo_flag & BO_ONWORKLST) && bo->bo_dirty.bv_cnt == 0) { 1919 mtx_lock(&sync_mtx); 1920 LIST_REMOVE(bo, bo_synclist); 1921 syncer_worklist_len--; 1922 mtx_unlock(&sync_mtx); 1923 bo->bo_flag &= ~BO_ONWORKLST; 1924 } 1925 } 1926 #ifdef INVARIANTS 1927 bv = &bo->bo_clean; 1928 bp = TAILQ_FIRST(&bv->bv_hd); 1929 KASSERT(bp == NULL || bp->b_bufobj == bo, 1930 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 1931 bp = TAILQ_LAST(&bv->bv_hd, buflists); 1932 KASSERT(bp == NULL || bp->b_bufobj == bo, 1933 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 1934 bv = &bo->bo_dirty; 1935 bp = TAILQ_FIRST(&bv->bv_hd); 1936 KASSERT(bp == NULL || bp->b_bufobj == bo, 1937 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 1938 bp = TAILQ_LAST(&bv->bv_hd, buflists); 1939 KASSERT(bp == NULL || bp->b_bufobj == bo, 1940 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 1941 #endif 1942 BO_UNLOCK(bo); 1943 } 1944 1945 /* 1946 * Increment the use and hold counts on the vnode, taking care to reference 1947 * the driver's usecount if this is a chardev. The vholdl() will remove 1948 * the vnode from the free list if it is presently free. Requires the 1949 * vnode interlock and returns with it held. 1950 */ 1951 static void 1952 v_incr_usecount(struct vnode *vp) 1953 { 1954 1955 CTR3(KTR_VFS, "v_incr_usecount: vp %p holdcnt %d usecount %d\n", 1956 vp, vp->v_holdcnt, vp->v_usecount); 1957 vp->v_usecount++; 1958 if (vp->v_type == VCHR && vp->v_rdev != NULL) { 1959 dev_lock(); 1960 vp->v_rdev->si_usecount++; 1961 dev_unlock(); 1962 } 1963 vholdl(vp); 1964 } 1965 1966 /* 1967 * Turn a holdcnt into a use+holdcnt such that only one call to 1968 * v_decr_usecount is needed. 1969 */ 1970 static void 1971 v_upgrade_usecount(struct vnode *vp) 1972 { 1973 1974 CTR3(KTR_VFS, "v_upgrade_usecount: vp %p holdcnt %d usecount %d\n", 1975 vp, vp->v_holdcnt, vp->v_usecount); 1976 vp->v_usecount++; 1977 if (vp->v_type == VCHR && vp->v_rdev != NULL) { 1978 dev_lock(); 1979 vp->v_rdev->si_usecount++; 1980 dev_unlock(); 1981 } 1982 } 1983 1984 /* 1985 * Decrement the vnode use and hold count along with the driver's usecount 1986 * if this is a chardev. The vdropl() below releases the vnode interlock 1987 * as it may free the vnode. 1988 */ 1989 static void 1990 v_decr_usecount(struct vnode *vp) 1991 { 1992 1993 CTR3(KTR_VFS, "v_decr_usecount: vp %p holdcnt %d usecount %d\n", 1994 vp, vp->v_holdcnt, vp->v_usecount); 1995 ASSERT_VI_LOCKED(vp, __FUNCTION__); 1996 VNASSERT(vp->v_usecount > 0, vp, 1997 ("v_decr_usecount: negative usecount")); 1998 vp->v_usecount--; 1999 if (vp->v_type == VCHR && vp->v_rdev != NULL) { 2000 dev_lock(); 2001 vp->v_rdev->si_usecount--; 2002 dev_unlock(); 2003 } 2004 vdropl(vp); 2005 } 2006 2007 /* 2008 * Decrement only the use count and driver use count. This is intended to 2009 * be paired with a follow on vdropl() to release the remaining hold count. 2010 * In this way we may vgone() a vnode with a 0 usecount without risk of 2011 * having it end up on a free list because the hold count is kept above 0. 2012 */ 2013 static void 2014 v_decr_useonly(struct vnode *vp) 2015 { 2016 2017 CTR3(KTR_VFS, "v_decr_useonly: vp %p holdcnt %d usecount %d\n", 2018 vp, vp->v_holdcnt, vp->v_usecount); 2019 ASSERT_VI_LOCKED(vp, __FUNCTION__); 2020 VNASSERT(vp->v_usecount > 0, vp, 2021 ("v_decr_useonly: negative usecount")); 2022 vp->v_usecount--; 2023 if (vp->v_type == VCHR && vp->v_rdev != NULL) { 2024 dev_lock(); 2025 vp->v_rdev->si_usecount--; 2026 dev_unlock(); 2027 } 2028 } 2029 2030 /* 2031 * Grab a particular vnode from the free list, increment its 2032 * reference count and lock it. VI_DOOMED is set if the vnode 2033 * is being destroyed. Only callers who specify LK_RETRY will 2034 * see doomed vnodes. If inactive processing was delayed in 2035 * vput try to do it here. 2036 */ 2037 int 2038 vget(struct vnode *vp, int flags, struct thread *td) 2039 { 2040 int error; 2041 2042 error = 0; 2043 VFS_ASSERT_GIANT(vp->v_mount); 2044 VNASSERT((flags & LK_TYPE_MASK) != 0, vp, 2045 ("vget: invalid lock operation")); 2046 if ((flags & LK_INTERLOCK) == 0) 2047 VI_LOCK(vp); 2048 vholdl(vp); 2049 if ((error = vn_lock(vp, flags | LK_INTERLOCK)) != 0) { 2050 vdrop(vp); 2051 return (error); 2052 } 2053 if (vp->v_iflag & VI_DOOMED && (flags & LK_RETRY) == 0) 2054 panic("vget: vn_lock failed to return ENOENT\n"); 2055 VI_LOCK(vp); 2056 /* Upgrade our holdcnt to a usecount. */ 2057 v_upgrade_usecount(vp); 2058 /* 2059 * We don't guarantee that any particular close will 2060 * trigger inactive processing so just make a best effort 2061 * here at preventing a reference to a removed file. If 2062 * we don't succeed no harm is done. 2063 */ 2064 if (vp->v_iflag & VI_OWEINACT) { 2065 if (VOP_ISLOCKED(vp) == LK_EXCLUSIVE && 2066 (flags & LK_NOWAIT) == 0) 2067 vinactive(vp, td); 2068 vp->v_iflag &= ~VI_OWEINACT; 2069 } 2070 VI_UNLOCK(vp); 2071 return (0); 2072 } 2073 2074 /* 2075 * Increase the reference count of a vnode. 2076 */ 2077 void 2078 vref(struct vnode *vp) 2079 { 2080 2081 VI_LOCK(vp); 2082 v_incr_usecount(vp); 2083 VI_UNLOCK(vp); 2084 } 2085 2086 /* 2087 * Return reference count of a vnode. 2088 * 2089 * The results of this call are only guaranteed when some mechanism other 2090 * than the VI lock is used to stop other processes from gaining references 2091 * to the vnode. This may be the case if the caller holds the only reference. 2092 * This is also useful when stale data is acceptable as race conditions may 2093 * be accounted for by some other means. 2094 */ 2095 int 2096 vrefcnt(struct vnode *vp) 2097 { 2098 int usecnt; 2099 2100 VI_LOCK(vp); 2101 usecnt = vp->v_usecount; 2102 VI_UNLOCK(vp); 2103 2104 return (usecnt); 2105 } 2106 2107 2108 /* 2109 * Vnode put/release. 2110 * If count drops to zero, call inactive routine and return to freelist. 2111 */ 2112 void 2113 vrele(struct vnode *vp) 2114 { 2115 struct thread *td = curthread; /* XXX */ 2116 2117 KASSERT(vp != NULL, ("vrele: null vp")); 2118 VFS_ASSERT_GIANT(vp->v_mount); 2119 2120 VI_LOCK(vp); 2121 2122 /* Skip this v_writecount check if we're going to panic below. */ 2123 VNASSERT(vp->v_writecount < vp->v_usecount || vp->v_usecount < 1, vp, 2124 ("vrele: missed vn_close")); 2125 2126 if (vp->v_usecount > 1 || ((vp->v_iflag & VI_DOINGINACT) && 2127 vp->v_usecount == 1)) { 2128 v_decr_usecount(vp); 2129 return; 2130 } 2131 if (vp->v_usecount != 1) { 2132 #ifdef DIAGNOSTIC 2133 vprint("vrele: negative ref count", vp); 2134 #endif 2135 VI_UNLOCK(vp); 2136 panic("vrele: negative ref cnt"); 2137 } 2138 /* 2139 * We want to hold the vnode until the inactive finishes to 2140 * prevent vgone() races. We drop the use count here and the 2141 * hold count below when we're done. 2142 */ 2143 v_decr_useonly(vp); 2144 /* 2145 * We must call VOP_INACTIVE with the node locked. Mark 2146 * as VI_DOINGINACT to avoid recursion. 2147 */ 2148 vp->v_iflag |= VI_OWEINACT; 2149 if (vn_lock(vp, LK_EXCLUSIVE | LK_INTERLOCK) == 0) { 2150 VI_LOCK(vp); 2151 if (vp->v_usecount > 0) 2152 vp->v_iflag &= ~VI_OWEINACT; 2153 if (vp->v_iflag & VI_OWEINACT) 2154 vinactive(vp, td); 2155 VOP_UNLOCK(vp, 0); 2156 } else { 2157 VI_LOCK(vp); 2158 if (vp->v_usecount > 0) 2159 vp->v_iflag &= ~VI_OWEINACT; 2160 } 2161 vdropl(vp); 2162 } 2163 2164 /* 2165 * Release an already locked vnode. This give the same effects as 2166 * unlock+vrele(), but takes less time and avoids releasing and 2167 * re-aquiring the lock (as vrele() acquires the lock internally.) 2168 */ 2169 void 2170 vput(struct vnode *vp) 2171 { 2172 struct thread *td = curthread; /* XXX */ 2173 int error; 2174 2175 KASSERT(vp != NULL, ("vput: null vp")); 2176 ASSERT_VOP_LOCKED(vp, "vput"); 2177 VFS_ASSERT_GIANT(vp->v_mount); 2178 VI_LOCK(vp); 2179 /* Skip this v_writecount check if we're going to panic below. */ 2180 VNASSERT(vp->v_writecount < vp->v_usecount || vp->v_usecount < 1, vp, 2181 ("vput: missed vn_close")); 2182 error = 0; 2183 2184 if (vp->v_usecount > 1 || ((vp->v_iflag & VI_DOINGINACT) && 2185 vp->v_usecount == 1)) { 2186 VOP_UNLOCK(vp, 0); 2187 v_decr_usecount(vp); 2188 return; 2189 } 2190 2191 if (vp->v_usecount != 1) { 2192 #ifdef DIAGNOSTIC 2193 vprint("vput: negative ref count", vp); 2194 #endif 2195 panic("vput: negative ref cnt"); 2196 } 2197 /* 2198 * We want to hold the vnode until the inactive finishes to 2199 * prevent vgone() races. We drop the use count here and the 2200 * hold count below when we're done. 2201 */ 2202 v_decr_useonly(vp); 2203 vp->v_iflag |= VI_OWEINACT; 2204 if (VOP_ISLOCKED(vp) != LK_EXCLUSIVE) { 2205 error = VOP_LOCK(vp, LK_UPGRADE|LK_INTERLOCK|LK_NOWAIT); 2206 VI_LOCK(vp); 2207 if (error) { 2208 if (vp->v_usecount > 0) 2209 vp->v_iflag &= ~VI_OWEINACT; 2210 goto done; 2211 } 2212 } 2213 if (vp->v_usecount > 0) 2214 vp->v_iflag &= ~VI_OWEINACT; 2215 if (vp->v_iflag & VI_OWEINACT) 2216 vinactive(vp, td); 2217 VOP_UNLOCK(vp, 0); 2218 done: 2219 vdropl(vp); 2220 } 2221 2222 /* 2223 * Somebody doesn't want the vnode recycled. 2224 */ 2225 void 2226 vhold(struct vnode *vp) 2227 { 2228 2229 VI_LOCK(vp); 2230 vholdl(vp); 2231 VI_UNLOCK(vp); 2232 } 2233 2234 void 2235 vholdl(struct vnode *vp) 2236 { 2237 2238 vp->v_holdcnt++; 2239 if (VSHOULDBUSY(vp)) 2240 vbusy(vp); 2241 } 2242 2243 /* 2244 * Note that there is one less who cares about this vnode. vdrop() is the 2245 * opposite of vhold(). 2246 */ 2247 void 2248 vdrop(struct vnode *vp) 2249 { 2250 2251 VI_LOCK(vp); 2252 vdropl(vp); 2253 } 2254 2255 /* 2256 * Drop the hold count of the vnode. If this is the last reference to 2257 * the vnode we will free it if it has been vgone'd otherwise it is 2258 * placed on the free list. 2259 */ 2260 void 2261 vdropl(struct vnode *vp) 2262 { 2263 2264 ASSERT_VI_LOCKED(vp, "vdropl"); 2265 if (vp->v_holdcnt <= 0) 2266 panic("vdrop: holdcnt %d", vp->v_holdcnt); 2267 vp->v_holdcnt--; 2268 if (vp->v_holdcnt == 0) { 2269 if (vp->v_iflag & VI_DOOMED) { 2270 vdestroy(vp); 2271 return; 2272 } else 2273 vfree(vp); 2274 } 2275 VI_UNLOCK(vp); 2276 } 2277 2278 /* 2279 * Call VOP_INACTIVE on the vnode and manage the DOINGINACT and OWEINACT 2280 * flags. DOINGINACT prevents us from recursing in calls to vinactive. 2281 * OWEINACT tracks whether a vnode missed a call to inactive due to a 2282 * failed lock upgrade. 2283 */ 2284 static void 2285 vinactive(struct vnode *vp, struct thread *td) 2286 { 2287 2288 ASSERT_VOP_ELOCKED(vp, "vinactive"); 2289 ASSERT_VI_LOCKED(vp, "vinactive"); 2290 VNASSERT((vp->v_iflag & VI_DOINGINACT) == 0, vp, 2291 ("vinactive: recursed on VI_DOINGINACT")); 2292 vp->v_iflag |= VI_DOINGINACT; 2293 vp->v_iflag &= ~VI_OWEINACT; 2294 VI_UNLOCK(vp); 2295 VOP_INACTIVE(vp, td); 2296 VI_LOCK(vp); 2297 VNASSERT(vp->v_iflag & VI_DOINGINACT, vp, 2298 ("vinactive: lost VI_DOINGINACT")); 2299 vp->v_iflag &= ~VI_DOINGINACT; 2300 } 2301 2302 /* 2303 * Remove any vnodes in the vnode table belonging to mount point mp. 2304 * 2305 * If FORCECLOSE is not specified, there should not be any active ones, 2306 * return error if any are found (nb: this is a user error, not a 2307 * system error). If FORCECLOSE is specified, detach any active vnodes 2308 * that are found. 2309 * 2310 * If WRITECLOSE is set, only flush out regular file vnodes open for 2311 * writing. 2312 * 2313 * SKIPSYSTEM causes any vnodes marked VV_SYSTEM to be skipped. 2314 * 2315 * `rootrefs' specifies the base reference count for the root vnode 2316 * of this filesystem. The root vnode is considered busy if its 2317 * v_usecount exceeds this value. On a successful return, vflush(, td) 2318 * will call vrele() on the root vnode exactly rootrefs times. 2319 * If the SKIPSYSTEM or WRITECLOSE flags are specified, rootrefs must 2320 * be zero. 2321 */ 2322 #ifdef DIAGNOSTIC 2323 static int busyprt = 0; /* print out busy vnodes */ 2324 SYSCTL_INT(_debug, OID_AUTO, busyprt, CTLFLAG_RW, &busyprt, 0, ""); 2325 #endif 2326 2327 int 2328 vflush( struct mount *mp, int rootrefs, int flags, struct thread *td) 2329 { 2330 struct vnode *vp, *mvp, *rootvp = NULL; 2331 struct vattr vattr; 2332 int busy = 0, error; 2333 2334 CTR1(KTR_VFS, "vflush: mp %p", mp); 2335 if (rootrefs > 0) { 2336 KASSERT((flags & (SKIPSYSTEM | WRITECLOSE)) == 0, 2337 ("vflush: bad args")); 2338 /* 2339 * Get the filesystem root vnode. We can vput() it 2340 * immediately, since with rootrefs > 0, it won't go away. 2341 */ 2342 if ((error = VFS_ROOT(mp, LK_EXCLUSIVE, &rootvp, td)) != 0) 2343 return (error); 2344 vput(rootvp); 2345 2346 } 2347 MNT_ILOCK(mp); 2348 loop: 2349 MNT_VNODE_FOREACH(vp, mp, mvp) { 2350 2351 VI_LOCK(vp); 2352 vholdl(vp); 2353 MNT_IUNLOCK(mp); 2354 error = vn_lock(vp, LK_INTERLOCK | LK_EXCLUSIVE); 2355 if (error) { 2356 vdrop(vp); 2357 MNT_ILOCK(mp); 2358 MNT_VNODE_FOREACH_ABORT_ILOCKED(mp, mvp); 2359 goto loop; 2360 } 2361 /* 2362 * Skip over a vnodes marked VV_SYSTEM. 2363 */ 2364 if ((flags & SKIPSYSTEM) && (vp->v_vflag & VV_SYSTEM)) { 2365 VOP_UNLOCK(vp, 0); 2366 vdrop(vp); 2367 MNT_ILOCK(mp); 2368 continue; 2369 } 2370 /* 2371 * If WRITECLOSE is set, flush out unlinked but still open 2372 * files (even if open only for reading) and regular file 2373 * vnodes open for writing. 2374 */ 2375 if (flags & WRITECLOSE) { 2376 error = VOP_GETATTR(vp, &vattr, td->td_ucred); 2377 VI_LOCK(vp); 2378 2379 if ((vp->v_type == VNON || 2380 (error == 0 && vattr.va_nlink > 0)) && 2381 (vp->v_writecount == 0 || vp->v_type != VREG)) { 2382 VOP_UNLOCK(vp, 0); 2383 vdropl(vp); 2384 MNT_ILOCK(mp); 2385 continue; 2386 } 2387 } else 2388 VI_LOCK(vp); 2389 /* 2390 * With v_usecount == 0, all we need to do is clear out the 2391 * vnode data structures and we are done. 2392 * 2393 * If FORCECLOSE is set, forcibly close the vnode. 2394 */ 2395 if (vp->v_usecount == 0 || (flags & FORCECLOSE)) { 2396 VNASSERT(vp->v_usecount == 0 || 2397 (vp->v_type != VCHR && vp->v_type != VBLK), vp, 2398 ("device VNODE %p is FORCECLOSED", vp)); 2399 vgonel(vp); 2400 } else { 2401 busy++; 2402 #ifdef DIAGNOSTIC 2403 if (busyprt) 2404 vprint("vflush: busy vnode", vp); 2405 #endif 2406 } 2407 VOP_UNLOCK(vp, 0); 2408 vdropl(vp); 2409 MNT_ILOCK(mp); 2410 } 2411 MNT_IUNLOCK(mp); 2412 if (rootrefs > 0 && (flags & FORCECLOSE) == 0) { 2413 /* 2414 * If just the root vnode is busy, and if its refcount 2415 * is equal to `rootrefs', then go ahead and kill it. 2416 */ 2417 VI_LOCK(rootvp); 2418 KASSERT(busy > 0, ("vflush: not busy")); 2419 VNASSERT(rootvp->v_usecount >= rootrefs, rootvp, 2420 ("vflush: usecount %d < rootrefs %d", 2421 rootvp->v_usecount, rootrefs)); 2422 if (busy == 1 && rootvp->v_usecount == rootrefs) { 2423 VOP_LOCK(rootvp, LK_EXCLUSIVE|LK_INTERLOCK); 2424 vgone(rootvp); 2425 VOP_UNLOCK(rootvp, 0); 2426 busy = 0; 2427 } else 2428 VI_UNLOCK(rootvp); 2429 } 2430 if (busy) 2431 return (EBUSY); 2432 for (; rootrefs > 0; rootrefs--) 2433 vrele(rootvp); 2434 return (0); 2435 } 2436 2437 /* 2438 * Recycle an unused vnode to the front of the free list. 2439 */ 2440 int 2441 vrecycle(struct vnode *vp, struct thread *td) 2442 { 2443 int recycled; 2444 2445 ASSERT_VOP_ELOCKED(vp, "vrecycle"); 2446 recycled = 0; 2447 VI_LOCK(vp); 2448 if (vp->v_usecount == 0) { 2449 recycled = 1; 2450 vgonel(vp); 2451 } 2452 VI_UNLOCK(vp); 2453 return (recycled); 2454 } 2455 2456 /* 2457 * Eliminate all activity associated with a vnode 2458 * in preparation for reuse. 2459 */ 2460 void 2461 vgone(struct vnode *vp) 2462 { 2463 VI_LOCK(vp); 2464 vgonel(vp); 2465 VI_UNLOCK(vp); 2466 } 2467 2468 /* 2469 * vgone, with the vp interlock held. 2470 */ 2471 void 2472 vgonel(struct vnode *vp) 2473 { 2474 struct thread *td; 2475 int oweinact; 2476 int active; 2477 struct mount *mp; 2478 2479 CTR1(KTR_VFS, "vgonel: vp %p", vp); 2480 ASSERT_VOP_ELOCKED(vp, "vgonel"); 2481 ASSERT_VI_LOCKED(vp, "vgonel"); 2482 VNASSERT(vp->v_holdcnt, vp, 2483 ("vgonel: vp %p has no reference.", vp)); 2484 td = curthread; 2485 2486 /* 2487 * Don't vgonel if we're already doomed. 2488 */ 2489 if (vp->v_iflag & VI_DOOMED) 2490 return; 2491 vp->v_iflag |= VI_DOOMED; 2492 /* 2493 * Check to see if the vnode is in use. If so, we have to call 2494 * VOP_CLOSE() and VOP_INACTIVE(). 2495 */ 2496 active = vp->v_usecount; 2497 oweinact = (vp->v_iflag & VI_OWEINACT); 2498 VI_UNLOCK(vp); 2499 /* 2500 * Clean out any buffers associated with the vnode. 2501 * If the flush fails, just toss the buffers. 2502 */ 2503 mp = NULL; 2504 if (!TAILQ_EMPTY(&vp->v_bufobj.bo_dirty.bv_hd)) 2505 (void) vn_start_secondary_write(vp, &mp, V_WAIT); 2506 if (vinvalbuf(vp, V_SAVE, 0, 0) != 0) 2507 vinvalbuf(vp, 0, 0, 0); 2508 2509 /* 2510 * If purging an active vnode, it must be closed and 2511 * deactivated before being reclaimed. 2512 */ 2513 if (active) 2514 VOP_CLOSE(vp, FNONBLOCK, NOCRED, td); 2515 if (oweinact || active) { 2516 VI_LOCK(vp); 2517 if ((vp->v_iflag & VI_DOINGINACT) == 0) 2518 vinactive(vp, td); 2519 VI_UNLOCK(vp); 2520 } 2521 /* 2522 * Reclaim the vnode. 2523 */ 2524 if (VOP_RECLAIM(vp, td)) 2525 panic("vgone: cannot reclaim"); 2526 if (mp != NULL) 2527 vn_finished_secondary_write(mp); 2528 VNASSERT(vp->v_object == NULL, vp, 2529 ("vop_reclaim left v_object vp=%p, tag=%s", vp, vp->v_tag)); 2530 /* 2531 * Clear the advisory locks and wake up waiting threads. 2532 */ 2533 lf_purgelocks(vp, &(vp->v_lockf)); 2534 /* 2535 * Delete from old mount point vnode list. 2536 */ 2537 delmntque(vp); 2538 cache_purge(vp); 2539 /* 2540 * Done with purge, reset to the standard lock and invalidate 2541 * the vnode. 2542 */ 2543 VI_LOCK(vp); 2544 vp->v_vnlock = &vp->v_lock; 2545 vp->v_op = &dead_vnodeops; 2546 vp->v_tag = "none"; 2547 vp->v_type = VBAD; 2548 } 2549 2550 /* 2551 * Calculate the total number of references to a special device. 2552 */ 2553 int 2554 vcount(struct vnode *vp) 2555 { 2556 int count; 2557 2558 dev_lock(); 2559 count = vp->v_rdev->si_usecount; 2560 dev_unlock(); 2561 return (count); 2562 } 2563 2564 /* 2565 * Same as above, but using the struct cdev *as argument 2566 */ 2567 int 2568 count_dev(struct cdev *dev) 2569 { 2570 int count; 2571 2572 dev_lock(); 2573 count = dev->si_usecount; 2574 dev_unlock(); 2575 return(count); 2576 } 2577 2578 /* 2579 * Print out a description of a vnode. 2580 */ 2581 static char *typename[] = 2582 {"VNON", "VREG", "VDIR", "VBLK", "VCHR", "VLNK", "VSOCK", "VFIFO", "VBAD", 2583 "VMARKER"}; 2584 2585 void 2586 vn_printf(struct vnode *vp, const char *fmt, ...) 2587 { 2588 va_list ap; 2589 char buf[256], buf2[16]; 2590 u_long flags; 2591 2592 va_start(ap, fmt); 2593 vprintf(fmt, ap); 2594 va_end(ap); 2595 printf("%p: ", (void *)vp); 2596 printf("tag %s, type %s\n", vp->v_tag, typename[vp->v_type]); 2597 printf(" usecount %d, writecount %d, refcount %d mountedhere %p\n", 2598 vp->v_usecount, vp->v_writecount, vp->v_holdcnt, vp->v_mountedhere); 2599 buf[0] = '\0'; 2600 buf[1] = '\0'; 2601 if (vp->v_vflag & VV_ROOT) 2602 strlcat(buf, "|VV_ROOT", sizeof(buf)); 2603 if (vp->v_vflag & VV_ISTTY) 2604 strlcat(buf, "|VV_ISTTY", sizeof(buf)); 2605 if (vp->v_vflag & VV_NOSYNC) 2606 strlcat(buf, "|VV_NOSYNC", sizeof(buf)); 2607 if (vp->v_vflag & VV_CACHEDLABEL) 2608 strlcat(buf, "|VV_CACHEDLABEL", sizeof(buf)); 2609 if (vp->v_vflag & VV_TEXT) 2610 strlcat(buf, "|VV_TEXT", sizeof(buf)); 2611 if (vp->v_vflag & VV_COPYONWRITE) 2612 strlcat(buf, "|VV_COPYONWRITE", sizeof(buf)); 2613 if (vp->v_vflag & VV_SYSTEM) 2614 strlcat(buf, "|VV_SYSTEM", sizeof(buf)); 2615 if (vp->v_vflag & VV_PROCDEP) 2616 strlcat(buf, "|VV_PROCDEP", sizeof(buf)); 2617 if (vp->v_vflag & VV_NOKNOTE) 2618 strlcat(buf, "|VV_NOKNOTE", sizeof(buf)); 2619 if (vp->v_vflag & VV_DELETED) 2620 strlcat(buf, "|VV_DELETED", sizeof(buf)); 2621 if (vp->v_vflag & VV_MD) 2622 strlcat(buf, "|VV_MD", sizeof(buf)); 2623 flags = vp->v_vflag & ~(VV_ROOT | VV_ISTTY | VV_NOSYNC | 2624 VV_CACHEDLABEL | VV_TEXT | VV_COPYONWRITE | VV_SYSTEM | VV_PROCDEP | 2625 VV_NOKNOTE | VV_DELETED | VV_MD); 2626 if (flags != 0) { 2627 snprintf(buf2, sizeof(buf2), "|VV(0x%lx)", flags); 2628 strlcat(buf, buf2, sizeof(buf)); 2629 } 2630 if (vp->v_iflag & VI_MOUNT) 2631 strlcat(buf, "|VI_MOUNT", sizeof(buf)); 2632 if (vp->v_iflag & VI_AGE) 2633 strlcat(buf, "|VI_AGE", sizeof(buf)); 2634 if (vp->v_iflag & VI_DOOMED) 2635 strlcat(buf, "|VI_DOOMED", sizeof(buf)); 2636 if (vp->v_iflag & VI_FREE) 2637 strlcat(buf, "|VI_FREE", sizeof(buf)); 2638 if (vp->v_iflag & VI_OBJDIRTY) 2639 strlcat(buf, "|VI_OBJDIRTY", sizeof(buf)); 2640 if (vp->v_iflag & VI_DOINGINACT) 2641 strlcat(buf, "|VI_DOINGINACT", sizeof(buf)); 2642 if (vp->v_iflag & VI_OWEINACT) 2643 strlcat(buf, "|VI_OWEINACT", sizeof(buf)); 2644 flags = vp->v_iflag & ~(VI_MOUNT | VI_AGE | VI_DOOMED | VI_FREE | 2645 VI_OBJDIRTY | VI_DOINGINACT | VI_OWEINACT); 2646 if (flags != 0) { 2647 snprintf(buf2, sizeof(buf2), "|VI(0x%lx)", flags); 2648 strlcat(buf, buf2, sizeof(buf)); 2649 } 2650 printf(" flags (%s)\n", buf + 1); 2651 if (mtx_owned(VI_MTX(vp))) 2652 printf(" VI_LOCKed"); 2653 if (vp->v_object != NULL) 2654 printf(" v_object %p ref %d pages %d\n", 2655 vp->v_object, vp->v_object->ref_count, 2656 vp->v_object->resident_page_count); 2657 printf(" "); 2658 lockmgr_printinfo(vp->v_vnlock); 2659 printf("\n"); 2660 if (vp->v_data != NULL) 2661 VOP_PRINT(vp); 2662 } 2663 2664 #ifdef DDB 2665 /* 2666 * List all of the locked vnodes in the system. 2667 * Called when debugging the kernel. 2668 */ 2669 DB_SHOW_COMMAND(lockedvnods, lockedvnodes) 2670 { 2671 struct mount *mp, *nmp; 2672 struct vnode *vp; 2673 2674 /* 2675 * Note: because this is DDB, we can't obey the locking semantics 2676 * for these structures, which means we could catch an inconsistent 2677 * state and dereference a nasty pointer. Not much to be done 2678 * about that. 2679 */ 2680 db_printf("Locked vnodes\n"); 2681 for (mp = TAILQ_FIRST(&mountlist); mp != NULL; mp = nmp) { 2682 nmp = TAILQ_NEXT(mp, mnt_list); 2683 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) { 2684 if (vp->v_type != VMARKER && 2685 VOP_ISLOCKED(vp)) 2686 vprint("", vp); 2687 } 2688 nmp = TAILQ_NEXT(mp, mnt_list); 2689 } 2690 } 2691 2692 /* 2693 * Show details about the given vnode. 2694 */ 2695 DB_SHOW_COMMAND(vnode, db_show_vnode) 2696 { 2697 struct vnode *vp; 2698 2699 if (!have_addr) 2700 return; 2701 vp = (struct vnode *)addr; 2702 vn_printf(vp, "vnode "); 2703 } 2704 2705 /* 2706 * Show details about the given mount point. 2707 */ 2708 DB_SHOW_COMMAND(mount, db_show_mount) 2709 { 2710 struct mount *mp; 2711 struct statfs *sp; 2712 struct vnode *vp; 2713 char buf[512]; 2714 u_int flags; 2715 2716 if (!have_addr) { 2717 /* No address given, print short info about all mount points. */ 2718 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 2719 db_printf("%p %s on %s (%s)\n", mp, 2720 mp->mnt_stat.f_mntfromname, 2721 mp->mnt_stat.f_mntonname, 2722 mp->mnt_stat.f_fstypename); 2723 if (db_pager_quit) 2724 break; 2725 } 2726 db_printf("\nMore info: show mount <addr>\n"); 2727 return; 2728 } 2729 2730 mp = (struct mount *)addr; 2731 db_printf("%p %s on %s (%s)\n", mp, mp->mnt_stat.f_mntfromname, 2732 mp->mnt_stat.f_mntonname, mp->mnt_stat.f_fstypename); 2733 2734 buf[0] = '\0'; 2735 flags = mp->mnt_flag; 2736 #define MNT_FLAG(flag) do { \ 2737 if (flags & (flag)) { \ 2738 if (buf[0] != '\0') \ 2739 strlcat(buf, ", ", sizeof(buf)); \ 2740 strlcat(buf, (#flag) + 4, sizeof(buf)); \ 2741 flags &= ~(flag); \ 2742 } \ 2743 } while (0) 2744 MNT_FLAG(MNT_RDONLY); 2745 MNT_FLAG(MNT_SYNCHRONOUS); 2746 MNT_FLAG(MNT_NOEXEC); 2747 MNT_FLAG(MNT_NOSUID); 2748 MNT_FLAG(MNT_UNION); 2749 MNT_FLAG(MNT_ASYNC); 2750 MNT_FLAG(MNT_SUIDDIR); 2751 MNT_FLAG(MNT_SOFTDEP); 2752 MNT_FLAG(MNT_NOSYMFOLLOW); 2753 MNT_FLAG(MNT_GJOURNAL); 2754 MNT_FLAG(MNT_MULTILABEL); 2755 MNT_FLAG(MNT_ACLS); 2756 MNT_FLAG(MNT_NOATIME); 2757 MNT_FLAG(MNT_NOCLUSTERR); 2758 MNT_FLAG(MNT_NOCLUSTERW); 2759 MNT_FLAG(MNT_EXRDONLY); 2760 MNT_FLAG(MNT_EXPORTED); 2761 MNT_FLAG(MNT_DEFEXPORTED); 2762 MNT_FLAG(MNT_EXPORTANON); 2763 MNT_FLAG(MNT_EXKERB); 2764 MNT_FLAG(MNT_EXPUBLIC); 2765 MNT_FLAG(MNT_LOCAL); 2766 MNT_FLAG(MNT_QUOTA); 2767 MNT_FLAG(MNT_ROOTFS); 2768 MNT_FLAG(MNT_USER); 2769 MNT_FLAG(MNT_IGNORE); 2770 MNT_FLAG(MNT_UPDATE); 2771 MNT_FLAG(MNT_DELEXPORT); 2772 MNT_FLAG(MNT_RELOAD); 2773 MNT_FLAG(MNT_FORCE); 2774 MNT_FLAG(MNT_SNAPSHOT); 2775 MNT_FLAG(MNT_BYFSID); 2776 #undef MNT_FLAG 2777 if (flags != 0) { 2778 if (buf[0] != '\0') 2779 strlcat(buf, ", ", sizeof(buf)); 2780 snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf), 2781 "0x%08x", flags); 2782 } 2783 db_printf(" mnt_flag = %s\n", buf); 2784 2785 buf[0] = '\0'; 2786 flags = mp->mnt_kern_flag; 2787 #define MNT_KERN_FLAG(flag) do { \ 2788 if (flags & (flag)) { \ 2789 if (buf[0] != '\0') \ 2790 strlcat(buf, ", ", sizeof(buf)); \ 2791 strlcat(buf, (#flag) + 5, sizeof(buf)); \ 2792 flags &= ~(flag); \ 2793 } \ 2794 } while (0) 2795 MNT_KERN_FLAG(MNTK_UNMOUNTF); 2796 MNT_KERN_FLAG(MNTK_ASYNC); 2797 MNT_KERN_FLAG(MNTK_SOFTDEP); 2798 MNT_KERN_FLAG(MNTK_NOINSMNTQ); 2799 MNT_KERN_FLAG(MNTK_UNMOUNT); 2800 MNT_KERN_FLAG(MNTK_MWAIT); 2801 MNT_KERN_FLAG(MNTK_SUSPEND); 2802 MNT_KERN_FLAG(MNTK_SUSPEND2); 2803 MNT_KERN_FLAG(MNTK_SUSPENDED); 2804 MNT_KERN_FLAG(MNTK_MPSAFE); 2805 MNT_KERN_FLAG(MNTK_NOKNOTE); 2806 MNT_KERN_FLAG(MNTK_LOOKUP_SHARED); 2807 #undef MNT_KERN_FLAG 2808 if (flags != 0) { 2809 if (buf[0] != '\0') 2810 strlcat(buf, ", ", sizeof(buf)); 2811 snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf), 2812 "0x%08x", flags); 2813 } 2814 db_printf(" mnt_kern_flag = %s\n", buf); 2815 2816 sp = &mp->mnt_stat; 2817 db_printf(" mnt_stat = { version=%u type=%u flags=0x%016jx " 2818 "bsize=%ju iosize=%ju blocks=%ju bfree=%ju bavail=%jd files=%ju " 2819 "ffree=%jd syncwrites=%ju asyncwrites=%ju syncreads=%ju " 2820 "asyncreads=%ju namemax=%u owner=%u fsid=[%d, %d] }\n", 2821 (u_int)sp->f_version, (u_int)sp->f_type, (uintmax_t)sp->f_flags, 2822 (uintmax_t)sp->f_bsize, (uintmax_t)sp->f_iosize, 2823 (uintmax_t)sp->f_blocks, (uintmax_t)sp->f_bfree, 2824 (intmax_t)sp->f_bavail, (uintmax_t)sp->f_files, 2825 (intmax_t)sp->f_ffree, (uintmax_t)sp->f_syncwrites, 2826 (uintmax_t)sp->f_asyncwrites, (uintmax_t)sp->f_syncreads, 2827 (uintmax_t)sp->f_asyncreads, (u_int)sp->f_namemax, 2828 (u_int)sp->f_owner, (int)sp->f_fsid.val[0], (int)sp->f_fsid.val[1]); 2829 2830 db_printf(" mnt_cred = { uid=%u ruid=%u", 2831 (u_int)mp->mnt_cred->cr_uid, (u_int)mp->mnt_cred->cr_ruid); 2832 if (mp->mnt_cred->cr_prison != NULL) 2833 db_printf(", jail=%d", mp->mnt_cred->cr_prison->pr_id); 2834 db_printf(" }\n"); 2835 db_printf(" mnt_ref = %d\n", mp->mnt_ref); 2836 db_printf(" mnt_gen = %d\n", mp->mnt_gen); 2837 db_printf(" mnt_nvnodelistsize = %d\n", mp->mnt_nvnodelistsize); 2838 db_printf(" mnt_writeopcount = %d\n", mp->mnt_writeopcount); 2839 db_printf(" mnt_noasync = %u\n", mp->mnt_noasync); 2840 db_printf(" mnt_maxsymlinklen = %d\n", mp->mnt_maxsymlinklen); 2841 db_printf(" mnt_iosize_max = %d\n", mp->mnt_iosize_max); 2842 db_printf(" mnt_hashseed = %u\n", mp->mnt_hashseed); 2843 db_printf(" mnt_markercnt = %d\n", mp->mnt_markercnt); 2844 db_printf(" mnt_holdcnt = %d\n", mp->mnt_holdcnt); 2845 db_printf(" mnt_holdcntwaiters = %d\n", mp->mnt_holdcntwaiters); 2846 db_printf(" mnt_secondary_writes = %d\n", mp->mnt_secondary_writes); 2847 db_printf(" mnt_secondary_accwrites = %d\n", 2848 mp->mnt_secondary_accwrites); 2849 db_printf(" mnt_gjprovider = %s\n", 2850 mp->mnt_gjprovider != NULL ? mp->mnt_gjprovider : "NULL"); 2851 db_printf("\n"); 2852 2853 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) { 2854 if (vp->v_type != VMARKER) { 2855 vn_printf(vp, "vnode "); 2856 if (db_pager_quit) 2857 break; 2858 } 2859 } 2860 } 2861 #endif /* DDB */ 2862 2863 /* 2864 * Fill in a struct xvfsconf based on a struct vfsconf. 2865 */ 2866 static void 2867 vfsconf2x(struct vfsconf *vfsp, struct xvfsconf *xvfsp) 2868 { 2869 2870 strcpy(xvfsp->vfc_name, vfsp->vfc_name); 2871 xvfsp->vfc_typenum = vfsp->vfc_typenum; 2872 xvfsp->vfc_refcount = vfsp->vfc_refcount; 2873 xvfsp->vfc_flags = vfsp->vfc_flags; 2874 /* 2875 * These are unused in userland, we keep them 2876 * to not break binary compatibility. 2877 */ 2878 xvfsp->vfc_vfsops = NULL; 2879 xvfsp->vfc_next = NULL; 2880 } 2881 2882 /* 2883 * Top level filesystem related information gathering. 2884 */ 2885 static int 2886 sysctl_vfs_conflist(SYSCTL_HANDLER_ARGS) 2887 { 2888 struct vfsconf *vfsp; 2889 struct xvfsconf xvfsp; 2890 int error; 2891 2892 error = 0; 2893 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) { 2894 bzero(&xvfsp, sizeof(xvfsp)); 2895 vfsconf2x(vfsp, &xvfsp); 2896 error = SYSCTL_OUT(req, &xvfsp, sizeof xvfsp); 2897 if (error) 2898 break; 2899 } 2900 return (error); 2901 } 2902 2903 SYSCTL_PROC(_vfs, OID_AUTO, conflist, CTLFLAG_RD, NULL, 0, sysctl_vfs_conflist, 2904 "S,xvfsconf", "List of all configured filesystems"); 2905 2906 #ifndef BURN_BRIDGES 2907 static int sysctl_ovfs_conf(SYSCTL_HANDLER_ARGS); 2908 2909 static int 2910 vfs_sysctl(SYSCTL_HANDLER_ARGS) 2911 { 2912 int *name = (int *)arg1 - 1; /* XXX */ 2913 u_int namelen = arg2 + 1; /* XXX */ 2914 struct vfsconf *vfsp; 2915 struct xvfsconf xvfsp; 2916 2917 printf("WARNING: userland calling deprecated sysctl, " 2918 "please rebuild world\n"); 2919 2920 #if 1 || defined(COMPAT_PRELITE2) 2921 /* Resolve ambiguity between VFS_VFSCONF and VFS_GENERIC. */ 2922 if (namelen == 1) 2923 return (sysctl_ovfs_conf(oidp, arg1, arg2, req)); 2924 #endif 2925 2926 switch (name[1]) { 2927 case VFS_MAXTYPENUM: 2928 if (namelen != 2) 2929 return (ENOTDIR); 2930 return (SYSCTL_OUT(req, &maxvfsconf, sizeof(int))); 2931 case VFS_CONF: 2932 if (namelen != 3) 2933 return (ENOTDIR); /* overloaded */ 2934 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) 2935 if (vfsp->vfc_typenum == name[2]) 2936 break; 2937 if (vfsp == NULL) 2938 return (EOPNOTSUPP); 2939 bzero(&xvfsp, sizeof(xvfsp)); 2940 vfsconf2x(vfsp, &xvfsp); 2941 return (SYSCTL_OUT(req, &xvfsp, sizeof(xvfsp))); 2942 } 2943 return (EOPNOTSUPP); 2944 } 2945 2946 static SYSCTL_NODE(_vfs, VFS_GENERIC, generic, CTLFLAG_RD | CTLFLAG_SKIP, 2947 vfs_sysctl, "Generic filesystem"); 2948 2949 #if 1 || defined(COMPAT_PRELITE2) 2950 2951 static int 2952 sysctl_ovfs_conf(SYSCTL_HANDLER_ARGS) 2953 { 2954 int error; 2955 struct vfsconf *vfsp; 2956 struct ovfsconf ovfs; 2957 2958 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) { 2959 bzero(&ovfs, sizeof(ovfs)); 2960 ovfs.vfc_vfsops = vfsp->vfc_vfsops; /* XXX used as flag */ 2961 strcpy(ovfs.vfc_name, vfsp->vfc_name); 2962 ovfs.vfc_index = vfsp->vfc_typenum; 2963 ovfs.vfc_refcount = vfsp->vfc_refcount; 2964 ovfs.vfc_flags = vfsp->vfc_flags; 2965 error = SYSCTL_OUT(req, &ovfs, sizeof ovfs); 2966 if (error) 2967 return error; 2968 } 2969 return 0; 2970 } 2971 2972 #endif /* 1 || COMPAT_PRELITE2 */ 2973 #endif /* !BURN_BRIDGES */ 2974 2975 #define KINFO_VNODESLOP 10 2976 #ifdef notyet 2977 /* 2978 * Dump vnode list (via sysctl). 2979 */ 2980 /* ARGSUSED */ 2981 static int 2982 sysctl_vnode(SYSCTL_HANDLER_ARGS) 2983 { 2984 struct xvnode *xvn; 2985 struct mount *mp; 2986 struct vnode *vp; 2987 int error, len, n; 2988 2989 /* 2990 * Stale numvnodes access is not fatal here. 2991 */ 2992 req->lock = 0; 2993 len = (numvnodes + KINFO_VNODESLOP) * sizeof *xvn; 2994 if (!req->oldptr) 2995 /* Make an estimate */ 2996 return (SYSCTL_OUT(req, 0, len)); 2997 2998 error = sysctl_wire_old_buffer(req, 0); 2999 if (error != 0) 3000 return (error); 3001 xvn = malloc(len, M_TEMP, M_ZERO | M_WAITOK); 3002 n = 0; 3003 mtx_lock(&mountlist_mtx); 3004 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 3005 if (vfs_busy(mp, LK_NOWAIT, &mountlist_mtx)) 3006 continue; 3007 MNT_ILOCK(mp); 3008 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) { 3009 if (n == len) 3010 break; 3011 vref(vp); 3012 xvn[n].xv_size = sizeof *xvn; 3013 xvn[n].xv_vnode = vp; 3014 xvn[n].xv_id = 0; /* XXX compat */ 3015 #define XV_COPY(field) xvn[n].xv_##field = vp->v_##field 3016 XV_COPY(usecount); 3017 XV_COPY(writecount); 3018 XV_COPY(holdcnt); 3019 XV_COPY(mount); 3020 XV_COPY(numoutput); 3021 XV_COPY(type); 3022 #undef XV_COPY 3023 xvn[n].xv_flag = vp->v_vflag; 3024 3025 switch (vp->v_type) { 3026 case VREG: 3027 case VDIR: 3028 case VLNK: 3029 break; 3030 case VBLK: 3031 case VCHR: 3032 if (vp->v_rdev == NULL) { 3033 vrele(vp); 3034 continue; 3035 } 3036 xvn[n].xv_dev = dev2udev(vp->v_rdev); 3037 break; 3038 case VSOCK: 3039 xvn[n].xv_socket = vp->v_socket; 3040 break; 3041 case VFIFO: 3042 xvn[n].xv_fifo = vp->v_fifoinfo; 3043 break; 3044 case VNON: 3045 case VBAD: 3046 default: 3047 /* shouldn't happen? */ 3048 vrele(vp); 3049 continue; 3050 } 3051 vrele(vp); 3052 ++n; 3053 } 3054 MNT_IUNLOCK(mp); 3055 mtx_lock(&mountlist_mtx); 3056 vfs_unbusy(mp); 3057 if (n == len) 3058 break; 3059 } 3060 mtx_unlock(&mountlist_mtx); 3061 3062 error = SYSCTL_OUT(req, xvn, n * sizeof *xvn); 3063 free(xvn, M_TEMP); 3064 return (error); 3065 } 3066 3067 SYSCTL_PROC(_kern, KERN_VNODE, vnode, CTLTYPE_OPAQUE|CTLFLAG_RD, 3068 0, 0, sysctl_vnode, "S,xvnode", ""); 3069 #endif 3070 3071 /* 3072 * Unmount all filesystems. The list is traversed in reverse order 3073 * of mounting to avoid dependencies. 3074 */ 3075 void 3076 vfs_unmountall(void) 3077 { 3078 struct mount *mp; 3079 struct thread *td; 3080 int error; 3081 3082 KASSERT(curthread != NULL, ("vfs_unmountall: NULL curthread")); 3083 td = curthread; 3084 /* 3085 * Since this only runs when rebooting, it is not interlocked. 3086 */ 3087 while(!TAILQ_EMPTY(&mountlist)) { 3088 mp = TAILQ_LAST(&mountlist, mntlist); 3089 error = dounmount(mp, MNT_FORCE, td); 3090 if (error) { 3091 TAILQ_REMOVE(&mountlist, mp, mnt_list); 3092 /* 3093 * XXX: Due to the way in which we mount the root 3094 * file system off of devfs, devfs will generate a 3095 * "busy" warning when we try to unmount it before 3096 * the root. Don't print a warning as a result in 3097 * order to avoid false positive errors that may 3098 * cause needless upset. 3099 */ 3100 if (strcmp(mp->mnt_vfc->vfc_name, "devfs") != 0) { 3101 printf("unmount of %s failed (", 3102 mp->mnt_stat.f_mntonname); 3103 if (error == EBUSY) 3104 printf("BUSY)\n"); 3105 else 3106 printf("%d)\n", error); 3107 } 3108 } else { 3109 /* The unmount has removed mp from the mountlist */ 3110 } 3111 } 3112 } 3113 3114 /* 3115 * perform msync on all vnodes under a mount point 3116 * the mount point must be locked. 3117 */ 3118 void 3119 vfs_msync(struct mount *mp, int flags) 3120 { 3121 struct vnode *vp, *mvp; 3122 struct vm_object *obj; 3123 3124 MNT_ILOCK(mp); 3125 MNT_VNODE_FOREACH(vp, mp, mvp) { 3126 VI_LOCK(vp); 3127 if ((vp->v_iflag & VI_OBJDIRTY) && 3128 (flags == MNT_WAIT || VOP_ISLOCKED(vp) == 0)) { 3129 MNT_IUNLOCK(mp); 3130 if (!vget(vp, 3131 LK_EXCLUSIVE | LK_RETRY | LK_INTERLOCK, 3132 curthread)) { 3133 if (vp->v_vflag & VV_NOSYNC) { /* unlinked */ 3134 vput(vp); 3135 MNT_ILOCK(mp); 3136 continue; 3137 } 3138 3139 obj = vp->v_object; 3140 if (obj != NULL) { 3141 VM_OBJECT_LOCK(obj); 3142 vm_object_page_clean(obj, 0, 0, 3143 flags == MNT_WAIT ? 3144 OBJPC_SYNC : OBJPC_NOSYNC); 3145 VM_OBJECT_UNLOCK(obj); 3146 } 3147 vput(vp); 3148 } 3149 MNT_ILOCK(mp); 3150 } else 3151 VI_UNLOCK(vp); 3152 } 3153 MNT_IUNLOCK(mp); 3154 } 3155 3156 /* 3157 * Mark a vnode as free, putting it up for recycling. 3158 */ 3159 static void 3160 vfree(struct vnode *vp) 3161 { 3162 3163 CTR1(KTR_VFS, "vfree vp %p", vp); 3164 ASSERT_VI_LOCKED(vp, "vfree"); 3165 mtx_lock(&vnode_free_list_mtx); 3166 VNASSERT(vp->v_op != NULL, vp, ("vfree: vnode already reclaimed.")); 3167 VNASSERT((vp->v_iflag & VI_FREE) == 0, vp, ("vnode already free")); 3168 VNASSERT(VSHOULDFREE(vp), vp, ("vfree: freeing when we shouldn't")); 3169 VNASSERT((vp->v_iflag & VI_DOOMED) == 0, vp, 3170 ("vfree: Freeing doomed vnode")); 3171 if (vp->v_iflag & VI_AGE) { 3172 TAILQ_INSERT_HEAD(&vnode_free_list, vp, v_freelist); 3173 } else { 3174 TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_freelist); 3175 } 3176 freevnodes++; 3177 vp->v_iflag &= ~VI_AGE; 3178 vp->v_iflag |= VI_FREE; 3179 mtx_unlock(&vnode_free_list_mtx); 3180 } 3181 3182 /* 3183 * Opposite of vfree() - mark a vnode as in use. 3184 */ 3185 static void 3186 vbusy(struct vnode *vp) 3187 { 3188 CTR1(KTR_VFS, "vbusy vp %p", vp); 3189 ASSERT_VI_LOCKED(vp, "vbusy"); 3190 VNASSERT((vp->v_iflag & VI_FREE) != 0, vp, ("vnode not free")); 3191 VNASSERT(vp->v_op != NULL, vp, ("vbusy: vnode already reclaimed.")); 3192 3193 mtx_lock(&vnode_free_list_mtx); 3194 TAILQ_REMOVE(&vnode_free_list, vp, v_freelist); 3195 freevnodes--; 3196 vp->v_iflag &= ~(VI_FREE|VI_AGE); 3197 mtx_unlock(&vnode_free_list_mtx); 3198 } 3199 3200 /* 3201 * Initalize per-vnode helper structure to hold poll-related state. 3202 */ 3203 void 3204 v_addpollinfo(struct vnode *vp) 3205 { 3206 struct vpollinfo *vi; 3207 3208 vi = uma_zalloc(vnodepoll_zone, M_WAITOK); 3209 if (vp->v_pollinfo != NULL) { 3210 uma_zfree(vnodepoll_zone, vi); 3211 return; 3212 } 3213 vp->v_pollinfo = vi; 3214 mtx_init(&vp->v_pollinfo->vpi_lock, "vnode pollinfo", NULL, MTX_DEF); 3215 knlist_init(&vp->v_pollinfo->vpi_selinfo.si_note, vp, vfs_knllock, 3216 vfs_knlunlock, vfs_knllocked); 3217 } 3218 3219 /* 3220 * Record a process's interest in events which might happen to 3221 * a vnode. Because poll uses the historic select-style interface 3222 * internally, this routine serves as both the ``check for any 3223 * pending events'' and the ``record my interest in future events'' 3224 * functions. (These are done together, while the lock is held, 3225 * to avoid race conditions.) 3226 */ 3227 int 3228 vn_pollrecord(struct vnode *vp, struct thread *td, int events) 3229 { 3230 3231 if (vp->v_pollinfo == NULL) 3232 v_addpollinfo(vp); 3233 mtx_lock(&vp->v_pollinfo->vpi_lock); 3234 if (vp->v_pollinfo->vpi_revents & events) { 3235 /* 3236 * This leaves events we are not interested 3237 * in available for the other process which 3238 * which presumably had requested them 3239 * (otherwise they would never have been 3240 * recorded). 3241 */ 3242 events &= vp->v_pollinfo->vpi_revents; 3243 vp->v_pollinfo->vpi_revents &= ~events; 3244 3245 mtx_unlock(&vp->v_pollinfo->vpi_lock); 3246 return events; 3247 } 3248 vp->v_pollinfo->vpi_events |= events; 3249 selrecord(td, &vp->v_pollinfo->vpi_selinfo); 3250 mtx_unlock(&vp->v_pollinfo->vpi_lock); 3251 return 0; 3252 } 3253 3254 /* 3255 * Routine to create and manage a filesystem syncer vnode. 3256 */ 3257 #define sync_close ((int (*)(struct vop_close_args *))nullop) 3258 static int sync_fsync(struct vop_fsync_args *); 3259 static int sync_inactive(struct vop_inactive_args *); 3260 static int sync_reclaim(struct vop_reclaim_args *); 3261 3262 static struct vop_vector sync_vnodeops = { 3263 .vop_bypass = VOP_EOPNOTSUPP, 3264 .vop_close = sync_close, /* close */ 3265 .vop_fsync = sync_fsync, /* fsync */ 3266 .vop_inactive = sync_inactive, /* inactive */ 3267 .vop_reclaim = sync_reclaim, /* reclaim */ 3268 .vop_lock1 = vop_stdlock, /* lock */ 3269 .vop_unlock = vop_stdunlock, /* unlock */ 3270 .vop_islocked = vop_stdislocked, /* islocked */ 3271 }; 3272 3273 /* 3274 * Create a new filesystem syncer vnode for the specified mount point. 3275 */ 3276 int 3277 vfs_allocate_syncvnode(struct mount *mp) 3278 { 3279 struct vnode *vp; 3280 struct bufobj *bo; 3281 static long start, incr, next; 3282 int error; 3283 3284 /* Allocate a new vnode */ 3285 if ((error = getnewvnode("syncer", mp, &sync_vnodeops, &vp)) != 0) { 3286 mp->mnt_syncer = NULL; 3287 return (error); 3288 } 3289 vp->v_type = VNON; 3290 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 3291 vp->v_vflag |= VV_FORCEINSMQ; 3292 error = insmntque(vp, mp); 3293 if (error != 0) 3294 panic("vfs_allocate_syncvnode: insmntque failed"); 3295 vp->v_vflag &= ~VV_FORCEINSMQ; 3296 VOP_UNLOCK(vp, 0); 3297 /* 3298 * Place the vnode onto the syncer worklist. We attempt to 3299 * scatter them about on the list so that they will go off 3300 * at evenly distributed times even if all the filesystems 3301 * are mounted at once. 3302 */ 3303 next += incr; 3304 if (next == 0 || next > syncer_maxdelay) { 3305 start /= 2; 3306 incr /= 2; 3307 if (start == 0) { 3308 start = syncer_maxdelay / 2; 3309 incr = syncer_maxdelay; 3310 } 3311 next = start; 3312 } 3313 bo = &vp->v_bufobj; 3314 BO_LOCK(bo); 3315 vn_syncer_add_to_worklist(bo, syncdelay > 0 ? next % syncdelay : 0); 3316 /* XXX - vn_syncer_add_to_worklist() also grabs and drops sync_mtx. */ 3317 mtx_lock(&sync_mtx); 3318 sync_vnode_count++; 3319 mtx_unlock(&sync_mtx); 3320 BO_UNLOCK(bo); 3321 mp->mnt_syncer = vp; 3322 return (0); 3323 } 3324 3325 /* 3326 * Do a lazy sync of the filesystem. 3327 */ 3328 static int 3329 sync_fsync(struct vop_fsync_args *ap) 3330 { 3331 struct vnode *syncvp = ap->a_vp; 3332 struct mount *mp = syncvp->v_mount; 3333 int error; 3334 struct bufobj *bo; 3335 3336 /* 3337 * We only need to do something if this is a lazy evaluation. 3338 */ 3339 if (ap->a_waitfor != MNT_LAZY) 3340 return (0); 3341 3342 /* 3343 * Move ourselves to the back of the sync list. 3344 */ 3345 bo = &syncvp->v_bufobj; 3346 BO_LOCK(bo); 3347 vn_syncer_add_to_worklist(bo, syncdelay); 3348 BO_UNLOCK(bo); 3349 3350 /* 3351 * Walk the list of vnodes pushing all that are dirty and 3352 * not already on the sync list. 3353 */ 3354 mtx_lock(&mountlist_mtx); 3355 if (vfs_busy(mp, LK_EXCLUSIVE | LK_NOWAIT, &mountlist_mtx) != 0) { 3356 mtx_unlock(&mountlist_mtx); 3357 return (0); 3358 } 3359 if (vn_start_write(NULL, &mp, V_NOWAIT) != 0) { 3360 vfs_unbusy(mp); 3361 return (0); 3362 } 3363 MNT_ILOCK(mp); 3364 mp->mnt_noasync++; 3365 mp->mnt_kern_flag &= ~MNTK_ASYNC; 3366 MNT_IUNLOCK(mp); 3367 vfs_msync(mp, MNT_NOWAIT); 3368 error = VFS_SYNC(mp, MNT_LAZY, ap->a_td); 3369 MNT_ILOCK(mp); 3370 mp->mnt_noasync--; 3371 if ((mp->mnt_flag & MNT_ASYNC) != 0 && mp->mnt_noasync == 0) 3372 mp->mnt_kern_flag |= MNTK_ASYNC; 3373 MNT_IUNLOCK(mp); 3374 vn_finished_write(mp); 3375 vfs_unbusy(mp); 3376 return (error); 3377 } 3378 3379 /* 3380 * The syncer vnode is no referenced. 3381 */ 3382 static int 3383 sync_inactive(struct vop_inactive_args *ap) 3384 { 3385 3386 vgone(ap->a_vp); 3387 return (0); 3388 } 3389 3390 /* 3391 * The syncer vnode is no longer needed and is being decommissioned. 3392 * 3393 * Modifications to the worklist must be protected by sync_mtx. 3394 */ 3395 static int 3396 sync_reclaim(struct vop_reclaim_args *ap) 3397 { 3398 struct vnode *vp = ap->a_vp; 3399 struct bufobj *bo; 3400 3401 bo = &vp->v_bufobj; 3402 BO_LOCK(bo); 3403 vp->v_mount->mnt_syncer = NULL; 3404 if (bo->bo_flag & BO_ONWORKLST) { 3405 mtx_lock(&sync_mtx); 3406 LIST_REMOVE(bo, bo_synclist); 3407 syncer_worklist_len--; 3408 sync_vnode_count--; 3409 mtx_unlock(&sync_mtx); 3410 bo->bo_flag &= ~BO_ONWORKLST; 3411 } 3412 BO_UNLOCK(bo); 3413 3414 return (0); 3415 } 3416 3417 /* 3418 * Check if vnode represents a disk device 3419 */ 3420 int 3421 vn_isdisk(struct vnode *vp, int *errp) 3422 { 3423 int error; 3424 3425 error = 0; 3426 dev_lock(); 3427 if (vp->v_type != VCHR) 3428 error = ENOTBLK; 3429 else if (vp->v_rdev == NULL) 3430 error = ENXIO; 3431 else if (vp->v_rdev->si_devsw == NULL) 3432 error = ENXIO; 3433 else if (!(vp->v_rdev->si_devsw->d_flags & D_DISK)) 3434 error = ENOTBLK; 3435 dev_unlock(); 3436 if (errp != NULL) 3437 *errp = error; 3438 return (error == 0); 3439 } 3440 3441 /* 3442 * Common filesystem object access control check routine. Accepts a 3443 * vnode's type, "mode", uid and gid, requested access mode, credentials, 3444 * and optional call-by-reference privused argument allowing vaccess() 3445 * to indicate to the caller whether privilege was used to satisfy the 3446 * request (obsoleted). Returns 0 on success, or an errno on failure. 3447 * 3448 * The ifdef'd CAPABILITIES version is here for reference, but is not 3449 * actually used. 3450 */ 3451 int 3452 vaccess(enum vtype type, mode_t file_mode, uid_t file_uid, gid_t file_gid, 3453 mode_t acc_mode, struct ucred *cred, int *privused) 3454 { 3455 mode_t dac_granted; 3456 mode_t priv_granted; 3457 3458 /* 3459 * Look for a normal, non-privileged way to access the file/directory 3460 * as requested. If it exists, go with that. 3461 */ 3462 3463 if (privused != NULL) 3464 *privused = 0; 3465 3466 dac_granted = 0; 3467 3468 /* Check the owner. */ 3469 if (cred->cr_uid == file_uid) { 3470 dac_granted |= VADMIN; 3471 if (file_mode & S_IXUSR) 3472 dac_granted |= VEXEC; 3473 if (file_mode & S_IRUSR) 3474 dac_granted |= VREAD; 3475 if (file_mode & S_IWUSR) 3476 dac_granted |= (VWRITE | VAPPEND); 3477 3478 if ((acc_mode & dac_granted) == acc_mode) 3479 return (0); 3480 3481 goto privcheck; 3482 } 3483 3484 /* Otherwise, check the groups (first match) */ 3485 if (groupmember(file_gid, cred)) { 3486 if (file_mode & S_IXGRP) 3487 dac_granted |= VEXEC; 3488 if (file_mode & S_IRGRP) 3489 dac_granted |= VREAD; 3490 if (file_mode & S_IWGRP) 3491 dac_granted |= (VWRITE | VAPPEND); 3492 3493 if ((acc_mode & dac_granted) == acc_mode) 3494 return (0); 3495 3496 goto privcheck; 3497 } 3498 3499 /* Otherwise, check everyone else. */ 3500 if (file_mode & S_IXOTH) 3501 dac_granted |= VEXEC; 3502 if (file_mode & S_IROTH) 3503 dac_granted |= VREAD; 3504 if (file_mode & S_IWOTH) 3505 dac_granted |= (VWRITE | VAPPEND); 3506 if ((acc_mode & dac_granted) == acc_mode) 3507 return (0); 3508 3509 privcheck: 3510 /* 3511 * Build a privilege mask to determine if the set of privileges 3512 * satisfies the requirements when combined with the granted mask 3513 * from above. For each privilege, if the privilege is required, 3514 * bitwise or the request type onto the priv_granted mask. 3515 */ 3516 priv_granted = 0; 3517 3518 if (type == VDIR) { 3519 /* 3520 * For directories, use PRIV_VFS_LOOKUP to satisfy VEXEC 3521 * requests, instead of PRIV_VFS_EXEC. 3522 */ 3523 if ((acc_mode & VEXEC) && ((dac_granted & VEXEC) == 0) && 3524 !priv_check_cred(cred, PRIV_VFS_LOOKUP, 0)) 3525 priv_granted |= VEXEC; 3526 } else { 3527 if ((acc_mode & VEXEC) && ((dac_granted & VEXEC) == 0) && 3528 !priv_check_cred(cred, PRIV_VFS_EXEC, 0)) 3529 priv_granted |= VEXEC; 3530 } 3531 3532 if ((acc_mode & VREAD) && ((dac_granted & VREAD) == 0) && 3533 !priv_check_cred(cred, PRIV_VFS_READ, 0)) 3534 priv_granted |= VREAD; 3535 3536 if ((acc_mode & VWRITE) && ((dac_granted & VWRITE) == 0) && 3537 !priv_check_cred(cred, PRIV_VFS_WRITE, 0)) 3538 priv_granted |= (VWRITE | VAPPEND); 3539 3540 if ((acc_mode & VADMIN) && ((dac_granted & VADMIN) == 0) && 3541 !priv_check_cred(cred, PRIV_VFS_ADMIN, 0)) 3542 priv_granted |= VADMIN; 3543 3544 if ((acc_mode & (priv_granted | dac_granted)) == acc_mode) { 3545 /* XXX audit: privilege used */ 3546 if (privused != NULL) 3547 *privused = 1; 3548 return (0); 3549 } 3550 3551 return ((acc_mode & VADMIN) ? EPERM : EACCES); 3552 } 3553 3554 /* 3555 * Credential check based on process requesting service, and per-attribute 3556 * permissions. 3557 */ 3558 int 3559 extattr_check_cred(struct vnode *vp, int attrnamespace, struct ucred *cred, 3560 struct thread *td, int access) 3561 { 3562 3563 /* 3564 * Kernel-invoked always succeeds. 3565 */ 3566 if (cred == NOCRED) 3567 return (0); 3568 3569 /* 3570 * Do not allow privileged processes in jail to directly manipulate 3571 * system attributes. 3572 */ 3573 switch (attrnamespace) { 3574 case EXTATTR_NAMESPACE_SYSTEM: 3575 /* Potentially should be: return (EPERM); */ 3576 return (priv_check_cred(cred, PRIV_VFS_EXTATTR_SYSTEM, 0)); 3577 case EXTATTR_NAMESPACE_USER: 3578 return (VOP_ACCESS(vp, access, cred, td)); 3579 default: 3580 return (EPERM); 3581 } 3582 } 3583 3584 #ifdef DEBUG_VFS_LOCKS 3585 /* 3586 * This only exists to supress warnings from unlocked specfs accesses. It is 3587 * no longer ok to have an unlocked VFS. 3588 */ 3589 #define IGNORE_LOCK(vp) (panicstr != NULL || (vp) == NULL || \ 3590 (vp)->v_type == VCHR || (vp)->v_type == VBAD) 3591 3592 int vfs_badlock_ddb = 1; /* Drop into debugger on violation. */ 3593 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_ddb, CTLFLAG_RW, &vfs_badlock_ddb, 0, ""); 3594 3595 int vfs_badlock_mutex = 1; /* Check for interlock across VOPs. */ 3596 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_mutex, CTLFLAG_RW, &vfs_badlock_mutex, 0, ""); 3597 3598 int vfs_badlock_print = 1; /* Print lock violations. */ 3599 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_print, CTLFLAG_RW, &vfs_badlock_print, 0, ""); 3600 3601 #ifdef KDB 3602 int vfs_badlock_backtrace = 1; /* Print backtrace at lock violations. */ 3603 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_backtrace, CTLFLAG_RW, &vfs_badlock_backtrace, 0, ""); 3604 #endif 3605 3606 static void 3607 vfs_badlock(const char *msg, const char *str, struct vnode *vp) 3608 { 3609 3610 #ifdef KDB 3611 if (vfs_badlock_backtrace) 3612 kdb_backtrace(); 3613 #endif 3614 if (vfs_badlock_print) 3615 printf("%s: %p %s\n", str, (void *)vp, msg); 3616 if (vfs_badlock_ddb) 3617 kdb_enter(KDB_WHY_VFSLOCK, "lock violation"); 3618 } 3619 3620 void 3621 assert_vi_locked(struct vnode *vp, const char *str) 3622 { 3623 3624 if (vfs_badlock_mutex && !mtx_owned(VI_MTX(vp))) 3625 vfs_badlock("interlock is not locked but should be", str, vp); 3626 } 3627 3628 void 3629 assert_vi_unlocked(struct vnode *vp, const char *str) 3630 { 3631 3632 if (vfs_badlock_mutex && mtx_owned(VI_MTX(vp))) 3633 vfs_badlock("interlock is locked but should not be", str, vp); 3634 } 3635 3636 void 3637 assert_vop_locked(struct vnode *vp, const char *str) 3638 { 3639 3640 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) == 0) 3641 vfs_badlock("is not locked but should be", str, vp); 3642 } 3643 3644 void 3645 assert_vop_unlocked(struct vnode *vp, const char *str) 3646 { 3647 3648 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) == LK_EXCLUSIVE) 3649 vfs_badlock("is locked but should not be", str, vp); 3650 } 3651 3652 void 3653 assert_vop_elocked(struct vnode *vp, const char *str) 3654 { 3655 3656 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) != LK_EXCLUSIVE) 3657 vfs_badlock("is not exclusive locked but should be", str, vp); 3658 } 3659 3660 #if 0 3661 void 3662 assert_vop_elocked_other(struct vnode *vp, const char *str) 3663 { 3664 3665 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) != LK_EXCLOTHER) 3666 vfs_badlock("is not exclusive locked by another thread", 3667 str, vp); 3668 } 3669 3670 void 3671 assert_vop_slocked(struct vnode *vp, const char *str) 3672 { 3673 3674 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) != LK_SHARED) 3675 vfs_badlock("is not locked shared but should be", str, vp); 3676 } 3677 #endif /* 0 */ 3678 #endif /* DEBUG_VFS_LOCKS */ 3679 3680 void 3681 vop_rename_pre(void *ap) 3682 { 3683 struct vop_rename_args *a = ap; 3684 3685 #ifdef DEBUG_VFS_LOCKS 3686 if (a->a_tvp) 3687 ASSERT_VI_UNLOCKED(a->a_tvp, "VOP_RENAME"); 3688 ASSERT_VI_UNLOCKED(a->a_tdvp, "VOP_RENAME"); 3689 ASSERT_VI_UNLOCKED(a->a_fvp, "VOP_RENAME"); 3690 ASSERT_VI_UNLOCKED(a->a_fdvp, "VOP_RENAME"); 3691 3692 /* Check the source (from). */ 3693 if (a->a_tdvp != a->a_fdvp && a->a_tvp != a->a_fdvp) 3694 ASSERT_VOP_UNLOCKED(a->a_fdvp, "vop_rename: fdvp locked"); 3695 if (a->a_tvp != a->a_fvp) 3696 ASSERT_VOP_UNLOCKED(a->a_fvp, "vop_rename: fvp locked"); 3697 3698 /* Check the target. */ 3699 if (a->a_tvp) 3700 ASSERT_VOP_LOCKED(a->a_tvp, "vop_rename: tvp not locked"); 3701 ASSERT_VOP_LOCKED(a->a_tdvp, "vop_rename: tdvp not locked"); 3702 #endif 3703 if (a->a_tdvp != a->a_fdvp) 3704 vhold(a->a_fdvp); 3705 if (a->a_tvp != a->a_fvp) 3706 vhold(a->a_fvp); 3707 vhold(a->a_tdvp); 3708 if (a->a_tvp) 3709 vhold(a->a_tvp); 3710 } 3711 3712 void 3713 vop_strategy_pre(void *ap) 3714 { 3715 #ifdef DEBUG_VFS_LOCKS 3716 struct vop_strategy_args *a; 3717 struct buf *bp; 3718 3719 a = ap; 3720 bp = a->a_bp; 3721 3722 /* 3723 * Cluster ops lock their component buffers but not the IO container. 3724 */ 3725 if ((bp->b_flags & B_CLUSTER) != 0) 3726 return; 3727 3728 if (!BUF_ISLOCKED(bp)) { 3729 if (vfs_badlock_print) 3730 printf( 3731 "VOP_STRATEGY: bp is not locked but should be\n"); 3732 if (vfs_badlock_ddb) 3733 kdb_enter(KDB_WHY_VFSLOCK, "lock violation"); 3734 } 3735 #endif 3736 } 3737 3738 void 3739 vop_lookup_pre(void *ap) 3740 { 3741 #ifdef DEBUG_VFS_LOCKS 3742 struct vop_lookup_args *a; 3743 struct vnode *dvp; 3744 3745 a = ap; 3746 dvp = a->a_dvp; 3747 ASSERT_VI_UNLOCKED(dvp, "VOP_LOOKUP"); 3748 ASSERT_VOP_LOCKED(dvp, "VOP_LOOKUP"); 3749 #endif 3750 } 3751 3752 void 3753 vop_lookup_post(void *ap, int rc) 3754 { 3755 #ifdef DEBUG_VFS_LOCKS 3756 struct vop_lookup_args *a; 3757 struct vnode *dvp; 3758 struct vnode *vp; 3759 3760 a = ap; 3761 dvp = a->a_dvp; 3762 vp = *(a->a_vpp); 3763 3764 ASSERT_VI_UNLOCKED(dvp, "VOP_LOOKUP"); 3765 ASSERT_VOP_LOCKED(dvp, "VOP_LOOKUP"); 3766 3767 if (!rc) 3768 ASSERT_VOP_LOCKED(vp, "VOP_LOOKUP (child)"); 3769 #endif 3770 } 3771 3772 void 3773 vop_lock_pre(void *ap) 3774 { 3775 #ifdef DEBUG_VFS_LOCKS 3776 struct vop_lock1_args *a = ap; 3777 3778 if ((a->a_flags & LK_INTERLOCK) == 0) 3779 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_LOCK"); 3780 else 3781 ASSERT_VI_LOCKED(a->a_vp, "VOP_LOCK"); 3782 #endif 3783 } 3784 3785 void 3786 vop_lock_post(void *ap, int rc) 3787 { 3788 #ifdef DEBUG_VFS_LOCKS 3789 struct vop_lock1_args *a = ap; 3790 3791 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_LOCK"); 3792 if (rc == 0) 3793 ASSERT_VOP_LOCKED(a->a_vp, "VOP_LOCK"); 3794 #endif 3795 } 3796 3797 void 3798 vop_unlock_pre(void *ap) 3799 { 3800 #ifdef DEBUG_VFS_LOCKS 3801 struct vop_unlock_args *a = ap; 3802 3803 if (a->a_flags & LK_INTERLOCK) 3804 ASSERT_VI_LOCKED(a->a_vp, "VOP_UNLOCK"); 3805 ASSERT_VOP_LOCKED(a->a_vp, "VOP_UNLOCK"); 3806 #endif 3807 } 3808 3809 void 3810 vop_unlock_post(void *ap, int rc) 3811 { 3812 #ifdef DEBUG_VFS_LOCKS 3813 struct vop_unlock_args *a = ap; 3814 3815 if (a->a_flags & LK_INTERLOCK) 3816 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_UNLOCK"); 3817 #endif 3818 } 3819 3820 void 3821 vop_create_post(void *ap, int rc) 3822 { 3823 struct vop_create_args *a = ap; 3824 3825 if (!rc) 3826 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 3827 } 3828 3829 void 3830 vop_link_post(void *ap, int rc) 3831 { 3832 struct vop_link_args *a = ap; 3833 3834 if (!rc) { 3835 VFS_KNOTE_LOCKED(a->a_vp, NOTE_LINK); 3836 VFS_KNOTE_LOCKED(a->a_tdvp, NOTE_WRITE); 3837 } 3838 } 3839 3840 void 3841 vop_mkdir_post(void *ap, int rc) 3842 { 3843 struct vop_mkdir_args *a = ap; 3844 3845 if (!rc) 3846 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE | NOTE_LINK); 3847 } 3848 3849 void 3850 vop_mknod_post(void *ap, int rc) 3851 { 3852 struct vop_mknod_args *a = ap; 3853 3854 if (!rc) 3855 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 3856 } 3857 3858 void 3859 vop_remove_post(void *ap, int rc) 3860 { 3861 struct vop_remove_args *a = ap; 3862 3863 if (!rc) { 3864 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 3865 VFS_KNOTE_LOCKED(a->a_vp, NOTE_DELETE); 3866 } 3867 } 3868 3869 void 3870 vop_rename_post(void *ap, int rc) 3871 { 3872 struct vop_rename_args *a = ap; 3873 3874 if (!rc) { 3875 VFS_KNOTE_UNLOCKED(a->a_fdvp, NOTE_WRITE); 3876 VFS_KNOTE_UNLOCKED(a->a_tdvp, NOTE_WRITE); 3877 VFS_KNOTE_UNLOCKED(a->a_fvp, NOTE_RENAME); 3878 if (a->a_tvp) 3879 VFS_KNOTE_UNLOCKED(a->a_tvp, NOTE_DELETE); 3880 } 3881 if (a->a_tdvp != a->a_fdvp) 3882 vdrop(a->a_fdvp); 3883 if (a->a_tvp != a->a_fvp) 3884 vdrop(a->a_fvp); 3885 vdrop(a->a_tdvp); 3886 if (a->a_tvp) 3887 vdrop(a->a_tvp); 3888 } 3889 3890 void 3891 vop_rmdir_post(void *ap, int rc) 3892 { 3893 struct vop_rmdir_args *a = ap; 3894 3895 if (!rc) { 3896 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE | NOTE_LINK); 3897 VFS_KNOTE_LOCKED(a->a_vp, NOTE_DELETE); 3898 } 3899 } 3900 3901 void 3902 vop_setattr_post(void *ap, int rc) 3903 { 3904 struct vop_setattr_args *a = ap; 3905 3906 if (!rc) 3907 VFS_KNOTE_LOCKED(a->a_vp, NOTE_ATTRIB); 3908 } 3909 3910 void 3911 vop_symlink_post(void *ap, int rc) 3912 { 3913 struct vop_symlink_args *a = ap; 3914 3915 if (!rc) 3916 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 3917 } 3918 3919 static struct knlist fs_knlist; 3920 3921 static void 3922 vfs_event_init(void *arg) 3923 { 3924 knlist_init(&fs_knlist, NULL, NULL, NULL, NULL); 3925 } 3926 /* XXX - correct order? */ 3927 SYSINIT(vfs_knlist, SI_SUB_VFS, SI_ORDER_ANY, vfs_event_init, NULL); 3928 3929 void 3930 vfs_event_signal(fsid_t *fsid, u_int32_t event, intptr_t data __unused) 3931 { 3932 3933 KNOTE_UNLOCKED(&fs_knlist, event); 3934 } 3935 3936 static int filt_fsattach(struct knote *kn); 3937 static void filt_fsdetach(struct knote *kn); 3938 static int filt_fsevent(struct knote *kn, long hint); 3939 3940 struct filterops fs_filtops = 3941 { 0, filt_fsattach, filt_fsdetach, filt_fsevent }; 3942 3943 static int 3944 filt_fsattach(struct knote *kn) 3945 { 3946 3947 kn->kn_flags |= EV_CLEAR; 3948 knlist_add(&fs_knlist, kn, 0); 3949 return (0); 3950 } 3951 3952 static void 3953 filt_fsdetach(struct knote *kn) 3954 { 3955 3956 knlist_remove(&fs_knlist, kn, 0); 3957 } 3958 3959 static int 3960 filt_fsevent(struct knote *kn, long hint) 3961 { 3962 3963 kn->kn_fflags |= hint; 3964 return (kn->kn_fflags != 0); 3965 } 3966 3967 static int 3968 sysctl_vfs_ctl(SYSCTL_HANDLER_ARGS) 3969 { 3970 struct vfsidctl vc; 3971 int error; 3972 struct mount *mp; 3973 3974 error = SYSCTL_IN(req, &vc, sizeof(vc)); 3975 if (error) 3976 return (error); 3977 if (vc.vc_vers != VFS_CTL_VERS1) 3978 return (EINVAL); 3979 mp = vfs_getvfs(&vc.vc_fsid); 3980 if (mp == NULL) 3981 return (ENOENT); 3982 /* ensure that a specific sysctl goes to the right filesystem. */ 3983 if (strcmp(vc.vc_fstypename, "*") != 0 && 3984 strcmp(vc.vc_fstypename, mp->mnt_vfc->vfc_name) != 0) { 3985 vfs_rel(mp); 3986 return (EINVAL); 3987 } 3988 VCTLTOREQ(&vc, req); 3989 error = VFS_SYSCTL(mp, vc.vc_op, req); 3990 vfs_rel(mp); 3991 return (error); 3992 } 3993 3994 SYSCTL_PROC(_vfs, OID_AUTO, ctl, CTLFLAG_WR, NULL, 0, sysctl_vfs_ctl, "", 3995 "Sysctl by fsid"); 3996 3997 /* 3998 * Function to initialize a va_filerev field sensibly. 3999 * XXX: Wouldn't a random number make a lot more sense ?? 4000 */ 4001 u_quad_t 4002 init_va_filerev(void) 4003 { 4004 struct bintime bt; 4005 4006 getbinuptime(&bt); 4007 return (((u_quad_t)bt.sec << 32LL) | (bt.frac >> 32LL)); 4008 } 4009 4010 static int filt_vfsread(struct knote *kn, long hint); 4011 static int filt_vfswrite(struct knote *kn, long hint); 4012 static int filt_vfsvnode(struct knote *kn, long hint); 4013 static void filt_vfsdetach(struct knote *kn); 4014 static struct filterops vfsread_filtops = 4015 { 1, NULL, filt_vfsdetach, filt_vfsread }; 4016 static struct filterops vfswrite_filtops = 4017 { 1, NULL, filt_vfsdetach, filt_vfswrite }; 4018 static struct filterops vfsvnode_filtops = 4019 { 1, NULL, filt_vfsdetach, filt_vfsvnode }; 4020 4021 static void 4022 vfs_knllock(void *arg) 4023 { 4024 struct vnode *vp = arg; 4025 4026 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 4027 } 4028 4029 static void 4030 vfs_knlunlock(void *arg) 4031 { 4032 struct vnode *vp = arg; 4033 4034 VOP_UNLOCK(vp, 0); 4035 } 4036 4037 static int 4038 vfs_knllocked(void *arg) 4039 { 4040 struct vnode *vp = arg; 4041 4042 return (VOP_ISLOCKED(vp) == LK_EXCLUSIVE); 4043 } 4044 4045 int 4046 vfs_kqfilter(struct vop_kqfilter_args *ap) 4047 { 4048 struct vnode *vp = ap->a_vp; 4049 struct knote *kn = ap->a_kn; 4050 struct knlist *knl; 4051 4052 switch (kn->kn_filter) { 4053 case EVFILT_READ: 4054 kn->kn_fop = &vfsread_filtops; 4055 break; 4056 case EVFILT_WRITE: 4057 kn->kn_fop = &vfswrite_filtops; 4058 break; 4059 case EVFILT_VNODE: 4060 kn->kn_fop = &vfsvnode_filtops; 4061 break; 4062 default: 4063 return (EINVAL); 4064 } 4065 4066 kn->kn_hook = (caddr_t)vp; 4067 4068 if (vp->v_pollinfo == NULL) 4069 v_addpollinfo(vp); 4070 if (vp->v_pollinfo == NULL) 4071 return (ENOMEM); 4072 knl = &vp->v_pollinfo->vpi_selinfo.si_note; 4073 knlist_add(knl, kn, 0); 4074 4075 return (0); 4076 } 4077 4078 /* 4079 * Detach knote from vnode 4080 */ 4081 static void 4082 filt_vfsdetach(struct knote *kn) 4083 { 4084 struct vnode *vp = (struct vnode *)kn->kn_hook; 4085 4086 KASSERT(vp->v_pollinfo != NULL, ("Missing v_pollinfo")); 4087 knlist_remove(&vp->v_pollinfo->vpi_selinfo.si_note, kn, 0); 4088 } 4089 4090 /*ARGSUSED*/ 4091 static int 4092 filt_vfsread(struct knote *kn, long hint) 4093 { 4094 struct vnode *vp = (struct vnode *)kn->kn_hook; 4095 struct vattr va; 4096 4097 /* 4098 * filesystem is gone, so set the EOF flag and schedule 4099 * the knote for deletion. 4100 */ 4101 if (hint == NOTE_REVOKE) { 4102 kn->kn_flags |= (EV_EOF | EV_ONESHOT); 4103 return (1); 4104 } 4105 4106 if (VOP_GETATTR(vp, &va, curthread->td_ucred)) 4107 return (0); 4108 4109 kn->kn_data = va.va_size - kn->kn_fp->f_offset; 4110 return (kn->kn_data != 0); 4111 } 4112 4113 /*ARGSUSED*/ 4114 static int 4115 filt_vfswrite(struct knote *kn, long hint) 4116 { 4117 /* 4118 * filesystem is gone, so set the EOF flag and schedule 4119 * the knote for deletion. 4120 */ 4121 if (hint == NOTE_REVOKE) 4122 kn->kn_flags |= (EV_EOF | EV_ONESHOT); 4123 4124 kn->kn_data = 0; 4125 return (1); 4126 } 4127 4128 static int 4129 filt_vfsvnode(struct knote *kn, long hint) 4130 { 4131 if (kn->kn_sfflags & hint) 4132 kn->kn_fflags |= hint; 4133 if (hint == NOTE_REVOKE) { 4134 kn->kn_flags |= EV_EOF; 4135 return (1); 4136 } 4137 return (kn->kn_fflags != 0); 4138 } 4139 4140 int 4141 vfs_read_dirent(struct vop_readdir_args *ap, struct dirent *dp, off_t off) 4142 { 4143 int error; 4144 4145 if (dp->d_reclen > ap->a_uio->uio_resid) 4146 return (ENAMETOOLONG); 4147 error = uiomove(dp, dp->d_reclen, ap->a_uio); 4148 if (error) { 4149 if (ap->a_ncookies != NULL) { 4150 if (ap->a_cookies != NULL) 4151 free(ap->a_cookies, M_TEMP); 4152 ap->a_cookies = NULL; 4153 *ap->a_ncookies = 0; 4154 } 4155 return (error); 4156 } 4157 if (ap->a_ncookies == NULL) 4158 return (0); 4159 4160 KASSERT(ap->a_cookies, 4161 ("NULL ap->a_cookies value with non-NULL ap->a_ncookies!")); 4162 4163 *ap->a_cookies = realloc(*ap->a_cookies, 4164 (*ap->a_ncookies + 1) * sizeof(u_long), M_TEMP, M_WAITOK | M_ZERO); 4165 (*ap->a_cookies)[*ap->a_ncookies] = off; 4166 return (0); 4167 } 4168 4169 /* 4170 * Mark for update the access time of the file if the filesystem 4171 * supports VA_MARK_ATIME. This functionality is used by execve 4172 * and mmap, so we want to avoid the synchronous I/O implied by 4173 * directly setting va_atime for the sake of efficiency. 4174 */ 4175 void 4176 vfs_mark_atime(struct vnode *vp, struct ucred *cred) 4177 { 4178 struct vattr atimeattr; 4179 4180 if ((vp->v_mount->mnt_flag & (MNT_NOATIME | MNT_RDONLY)) == 0) { 4181 VATTR_NULL(&atimeattr); 4182 atimeattr.va_vaflags |= VA_MARK_ATIME; 4183 (void)VOP_SETATTR(vp, &atimeattr, cred); 4184 } 4185 } 4186