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_watchdog.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/sched.h> 70 #include <sys/sleepqueue.h> 71 #include <sys/stat.h> 72 #include <sys/sysctl.h> 73 #include <sys/syslog.h> 74 #include <sys/vmmeter.h> 75 #include <sys/vnode.h> 76 #ifdef SW_WATCHDOG 77 #include <sys/watchdog.h> 78 #endif 79 80 #include <machine/stdarg.h> 81 82 #include <security/mac/mac_framework.h> 83 84 #include <vm/vm.h> 85 #include <vm/vm_object.h> 86 #include <vm/vm_extern.h> 87 #include <vm/pmap.h> 88 #include <vm/vm_map.h> 89 #include <vm/vm_page.h> 90 #include <vm/vm_kern.h> 91 #include <vm/uma.h> 92 93 #ifdef DDB 94 #include <ddb/ddb.h> 95 #endif 96 97 #define WI_MPSAFEQ 0 98 #define WI_GIANTQ 1 99 100 static void delmntque(struct vnode *vp); 101 static int flushbuflist(struct bufv *bufv, int flags, struct bufobj *bo, 102 int slpflag, int slptimeo); 103 static void syncer_shutdown(void *arg, int howto); 104 static int vtryrecycle(struct vnode *vp); 105 static void vbusy(struct vnode *vp); 106 static void vinactive(struct vnode *, struct thread *); 107 static void v_incr_usecount(struct vnode *); 108 static void v_decr_usecount(struct vnode *); 109 static void v_decr_useonly(struct vnode *); 110 static void v_upgrade_usecount(struct vnode *); 111 static void vfree(struct vnode *); 112 static void vnlru_free(int); 113 static void vgonel(struct vnode *); 114 static void vfs_knllock(void *arg); 115 static void vfs_knlunlock(void *arg); 116 static void vfs_knl_assert_locked(void *arg); 117 static void vfs_knl_assert_unlocked(void *arg); 118 static void destroy_vpollinfo(struct vpollinfo *vi); 119 120 /* 121 * Number of vnodes in existence. Increased whenever getnewvnode() 122 * allocates a new vnode, decreased on vdestroy() called on VI_DOOMed 123 * vnode. 124 */ 125 static unsigned long numvnodes; 126 127 SYSCTL_ULONG(_vfs, OID_AUTO, numvnodes, CTLFLAG_RD, &numvnodes, 0, 128 "Number of vnodes in existence"); 129 130 /* 131 * Conversion tables for conversion from vnode types to inode formats 132 * and back. 133 */ 134 enum vtype iftovt_tab[16] = { 135 VNON, VFIFO, VCHR, VNON, VDIR, VNON, VBLK, VNON, 136 VREG, VNON, VLNK, VNON, VSOCK, VNON, VNON, VBAD, 137 }; 138 int vttoif_tab[10] = { 139 0, S_IFREG, S_IFDIR, S_IFBLK, S_IFCHR, S_IFLNK, 140 S_IFSOCK, S_IFIFO, S_IFMT, S_IFMT 141 }; 142 143 /* 144 * List of vnodes that are ready for recycling. 145 */ 146 static TAILQ_HEAD(freelst, vnode) vnode_free_list; 147 148 /* 149 * Free vnode target. Free vnodes may simply be files which have been stat'd 150 * but not read. This is somewhat common, and a small cache of such files 151 * should be kept to avoid recreation costs. 152 */ 153 static u_long wantfreevnodes; 154 SYSCTL_ULONG(_vfs, OID_AUTO, wantfreevnodes, CTLFLAG_RW, &wantfreevnodes, 0, ""); 155 /* Number of vnodes in the free list. */ 156 static u_long freevnodes; 157 SYSCTL_ULONG(_vfs, OID_AUTO, freevnodes, CTLFLAG_RD, &freevnodes, 0, 158 "Number of vnodes in the free list"); 159 160 static int vlru_allow_cache_src; 161 SYSCTL_INT(_vfs, OID_AUTO, vlru_allow_cache_src, CTLFLAG_RW, 162 &vlru_allow_cache_src, 0, "Allow vlru to reclaim source vnode"); 163 164 /* 165 * Various variables used for debugging the new implementation of 166 * reassignbuf(). 167 * XXX these are probably of (very) limited utility now. 168 */ 169 static int reassignbufcalls; 170 SYSCTL_INT(_vfs, OID_AUTO, reassignbufcalls, CTLFLAG_RW, &reassignbufcalls, 0, 171 "Number of calls to reassignbuf"); 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 /* 198 * The workitem queue. 199 * 200 * It is useful to delay writes of file data and filesystem metadata 201 * for tens of seconds so that quickly created and deleted files need 202 * not waste disk bandwidth being created and removed. To realize this, 203 * we append vnodes to a "workitem" queue. When running with a soft 204 * updates implementation, most pending metadata dependencies should 205 * not wait for more than a few seconds. Thus, mounted on block devices 206 * are delayed only about a half the time that file data is delayed. 207 * Similarly, directory updates are more critical, so are only delayed 208 * about a third the time that file data is delayed. Thus, there are 209 * SYNCER_MAXDELAY queues that are processed round-robin at a rate of 210 * one each second (driven off the filesystem syncer process). The 211 * syncer_delayno variable indicates the next queue that is to be processed. 212 * Items that need to be processed soon are placed in this queue: 213 * 214 * syncer_workitem_pending[syncer_delayno] 215 * 216 * A delay of fifteen seconds is done by placing the request fifteen 217 * entries later in the queue: 218 * 219 * syncer_workitem_pending[(syncer_delayno + 15) & syncer_mask] 220 * 221 */ 222 static int syncer_delayno; 223 static long syncer_mask; 224 LIST_HEAD(synclist, bufobj); 225 static struct synclist *syncer_workitem_pending[2]; 226 /* 227 * The sync_mtx protects: 228 * bo->bo_synclist 229 * sync_vnode_count 230 * syncer_delayno 231 * syncer_state 232 * syncer_workitem_pending 233 * syncer_worklist_len 234 * rushjob 235 */ 236 static struct mtx sync_mtx; 237 static struct cv sync_wakeup; 238 239 #define SYNCER_MAXDELAY 32 240 static int syncer_maxdelay = SYNCER_MAXDELAY; /* maximum delay time */ 241 static int syncdelay = 30; /* max time to delay syncing data */ 242 static int filedelay = 30; /* time to delay syncing files */ 243 SYSCTL_INT(_kern, OID_AUTO, filedelay, CTLFLAG_RW, &filedelay, 0, 244 "Time to delay syncing files (in seconds)"); 245 static int dirdelay = 29; /* time to delay syncing directories */ 246 SYSCTL_INT(_kern, OID_AUTO, dirdelay, CTLFLAG_RW, &dirdelay, 0, 247 "Time to delay syncing directories (in seconds)"); 248 static int metadelay = 28; /* time to delay syncing metadata */ 249 SYSCTL_INT(_kern, OID_AUTO, metadelay, CTLFLAG_RW, &metadelay, 0, 250 "Time to delay syncing metadata (in seconds)"); 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 "Number of times I/O speeded up (rush requests)"); 255 256 /* 257 * When shutting down the syncer, run it at four times normal speed. 258 */ 259 #define SYNCER_SHUTDOWN_SPEEDUP 4 260 static int sync_vnode_count; 261 static int syncer_worklist_len; 262 static enum { SYNCER_RUNNING, SYNCER_SHUTTING_DOWN, SYNCER_FINAL_DELAY } 263 syncer_state; 264 265 /* 266 * Number of vnodes we want to exist at any one time. This is mostly used 267 * to size hash tables in vnode-related code. It is normally not used in 268 * getnewvnode(), as wantfreevnodes is normally nonzero.) 269 * 270 * XXX desiredvnodes is historical cruft and should not exist. 271 */ 272 int desiredvnodes; 273 SYSCTL_INT(_kern, KERN_MAXVNODES, maxvnodes, CTLFLAG_RW, 274 &desiredvnodes, 0, "Maximum number of vnodes"); 275 SYSCTL_ULONG(_kern, OID_AUTO, minvnodes, CTLFLAG_RW, 276 &wantfreevnodes, 0, "Minimum number of vnodes (legacy)"); 277 static int vnlru_nowhere; 278 SYSCTL_INT(_debug, OID_AUTO, vnlru_nowhere, CTLFLAG_RW, 279 &vnlru_nowhere, 0, "Number of times the vnlru process ran without success"); 280 281 /* 282 * Macros to control when a vnode is freed and recycled. All require 283 * the vnode interlock. 284 */ 285 #define VCANRECYCLE(vp) (((vp)->v_iflag & VI_FREE) && !(vp)->v_holdcnt) 286 #define VSHOULDFREE(vp) (!((vp)->v_iflag & VI_FREE) && !(vp)->v_holdcnt) 287 #define VSHOULDBUSY(vp) (((vp)->v_iflag & VI_FREE) && (vp)->v_holdcnt) 288 289 290 /* 291 * Initialize the vnode management data structures. 292 * 293 * Reevaluate the following cap on the number of vnodes after the physical 294 * memory size exceeds 512GB. In the limit, as the physical memory size 295 * grows, the ratio of physical pages to vnodes approaches sixteen to one. 296 */ 297 #ifndef MAXVNODES_MAX 298 #define MAXVNODES_MAX (512 * (1024 * 1024 * 1024 / (int)PAGE_SIZE / 16)) 299 #endif 300 static void 301 vntblinit(void *dummy __unused) 302 { 303 int physvnodes, virtvnodes; 304 305 /* 306 * Desiredvnodes is a function of the physical memory size and the 307 * kernel's heap size. Generally speaking, it scales with the 308 * physical memory size. The ratio of desiredvnodes to physical pages 309 * is one to four until desiredvnodes exceeds 98,304. Thereafter, the 310 * marginal ratio of desiredvnodes to physical pages is one to 311 * sixteen. However, desiredvnodes is limited by the kernel's heap 312 * size. The memory required by desiredvnodes vnodes and vm objects 313 * may not exceed one seventh of the kernel's heap size. 314 */ 315 physvnodes = maxproc + cnt.v_page_count / 16 + 3 * min(98304 * 4, 316 cnt.v_page_count) / 16; 317 virtvnodes = vm_kmem_size / (7 * (sizeof(struct vm_object) + 318 sizeof(struct vnode))); 319 desiredvnodes = min(physvnodes, virtvnodes); 320 if (desiredvnodes > MAXVNODES_MAX) { 321 if (bootverbose) 322 printf("Reducing kern.maxvnodes %d -> %d\n", 323 desiredvnodes, MAXVNODES_MAX); 324 desiredvnodes = MAXVNODES_MAX; 325 } 326 wantfreevnodes = desiredvnodes / 4; 327 mtx_init(&mntid_mtx, "mntid", NULL, MTX_DEF); 328 TAILQ_INIT(&vnode_free_list); 329 mtx_init(&vnode_free_list_mtx, "vnode_free_list", NULL, MTX_DEF); 330 vnode_zone = uma_zcreate("VNODE", sizeof (struct vnode), NULL, NULL, 331 NULL, NULL, UMA_ALIGN_PTR, 0); 332 vnodepoll_zone = uma_zcreate("VNODEPOLL", sizeof (struct vpollinfo), 333 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); 334 /* 335 * Initialize the filesystem syncer. 336 */ 337 syncer_workitem_pending[WI_MPSAFEQ] = hashinit(syncer_maxdelay, M_VNODE, 338 &syncer_mask); 339 syncer_workitem_pending[WI_GIANTQ] = hashinit(syncer_maxdelay, M_VNODE, 340 &syncer_mask); 341 syncer_maxdelay = syncer_mask + 1; 342 mtx_init(&sync_mtx, "Syncer mtx", NULL, MTX_DEF); 343 cv_init(&sync_wakeup, "syncer"); 344 } 345 SYSINIT(vfs, SI_SUB_VFS, SI_ORDER_FIRST, vntblinit, NULL); 346 347 348 /* 349 * Mark a mount point as busy. Used to synchronize access and to delay 350 * unmounting. Eventually, mountlist_mtx is not released on failure. 351 */ 352 int 353 vfs_busy(struct mount *mp, int flags) 354 { 355 356 MPASS((flags & ~MBF_MASK) == 0); 357 CTR3(KTR_VFS, "%s: mp %p with flags %d", __func__, mp, flags); 358 359 MNT_ILOCK(mp); 360 MNT_REF(mp); 361 /* 362 * If mount point is currenly being unmounted, sleep until the 363 * mount point fate is decided. If thread doing the unmounting fails, 364 * it will clear MNTK_UNMOUNT flag before waking us up, indicating 365 * that this mount point has survived the unmount attempt and vfs_busy 366 * should retry. Otherwise the unmounter thread will set MNTK_REFEXPIRE 367 * flag in addition to MNTK_UNMOUNT, indicating that mount point is 368 * about to be really destroyed. vfs_busy needs to release its 369 * reference on the mount point in this case and return with ENOENT, 370 * telling the caller that mount mount it tried to busy is no longer 371 * valid. 372 */ 373 while (mp->mnt_kern_flag & MNTK_UNMOUNT) { 374 if (flags & MBF_NOWAIT || mp->mnt_kern_flag & MNTK_REFEXPIRE) { 375 MNT_REL(mp); 376 MNT_IUNLOCK(mp); 377 CTR1(KTR_VFS, "%s: failed busying before sleeping", 378 __func__); 379 return (ENOENT); 380 } 381 if (flags & MBF_MNTLSTLOCK) 382 mtx_unlock(&mountlist_mtx); 383 mp->mnt_kern_flag |= MNTK_MWAIT; 384 msleep(mp, MNT_MTX(mp), PVFS | PDROP, "vfs_busy", 0); 385 if (flags & MBF_MNTLSTLOCK) 386 mtx_lock(&mountlist_mtx); 387 MNT_ILOCK(mp); 388 } 389 if (flags & MBF_MNTLSTLOCK) 390 mtx_unlock(&mountlist_mtx); 391 mp->mnt_lockref++; 392 MNT_IUNLOCK(mp); 393 return (0); 394 } 395 396 /* 397 * Free a busy filesystem. 398 */ 399 void 400 vfs_unbusy(struct mount *mp) 401 { 402 403 CTR2(KTR_VFS, "%s: mp %p", __func__, mp); 404 MNT_ILOCK(mp); 405 MNT_REL(mp); 406 KASSERT(mp->mnt_lockref > 0, ("negative mnt_lockref")); 407 mp->mnt_lockref--; 408 if (mp->mnt_lockref == 0 && (mp->mnt_kern_flag & MNTK_DRAINING) != 0) { 409 MPASS(mp->mnt_kern_flag & MNTK_UNMOUNT); 410 CTR1(KTR_VFS, "%s: waking up waiters", __func__); 411 mp->mnt_kern_flag &= ~MNTK_DRAINING; 412 wakeup(&mp->mnt_lockref); 413 } 414 MNT_IUNLOCK(mp); 415 } 416 417 /* 418 * Lookup a mount point by filesystem identifier. 419 */ 420 struct mount * 421 vfs_getvfs(fsid_t *fsid) 422 { 423 struct mount *mp; 424 425 CTR2(KTR_VFS, "%s: fsid %p", __func__, fsid); 426 mtx_lock(&mountlist_mtx); 427 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 428 if (mp->mnt_stat.f_fsid.val[0] == fsid->val[0] && 429 mp->mnt_stat.f_fsid.val[1] == fsid->val[1]) { 430 vfs_ref(mp); 431 mtx_unlock(&mountlist_mtx); 432 return (mp); 433 } 434 } 435 mtx_unlock(&mountlist_mtx); 436 CTR2(KTR_VFS, "%s: lookup failed for %p id", __func__, fsid); 437 return ((struct mount *) 0); 438 } 439 440 /* 441 * Lookup a mount point by filesystem identifier, busying it before 442 * returning. 443 */ 444 struct mount * 445 vfs_busyfs(fsid_t *fsid) 446 { 447 struct mount *mp; 448 int error; 449 450 CTR2(KTR_VFS, "%s: fsid %p", __func__, fsid); 451 mtx_lock(&mountlist_mtx); 452 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 453 if (mp->mnt_stat.f_fsid.val[0] == fsid->val[0] && 454 mp->mnt_stat.f_fsid.val[1] == fsid->val[1]) { 455 error = vfs_busy(mp, MBF_MNTLSTLOCK); 456 if (error) { 457 mtx_unlock(&mountlist_mtx); 458 return (NULL); 459 } 460 return (mp); 461 } 462 } 463 CTR2(KTR_VFS, "%s: lookup failed for %p id", __func__, fsid); 464 mtx_unlock(&mountlist_mtx); 465 return ((struct mount *) 0); 466 } 467 468 /* 469 * Check if a user can access privileged mount options. 470 */ 471 int 472 vfs_suser(struct mount *mp, struct thread *td) 473 { 474 int error; 475 476 /* 477 * If the thread is jailed, but this is not a jail-friendly file 478 * system, deny immediately. 479 */ 480 if (!(mp->mnt_vfc->vfc_flags & VFCF_JAIL) && jailed(td->td_ucred)) 481 return (EPERM); 482 483 /* 484 * If the file system was mounted outside the jail of the calling 485 * thread, deny immediately. 486 */ 487 if (prison_check(td->td_ucred, mp->mnt_cred) != 0) 488 return (EPERM); 489 490 /* 491 * If file system supports delegated administration, we don't check 492 * for the PRIV_VFS_MOUNT_OWNER privilege - it will be better verified 493 * by the file system itself. 494 * If this is not the user that did original mount, we check for 495 * the PRIV_VFS_MOUNT_OWNER privilege. 496 */ 497 if (!(mp->mnt_vfc->vfc_flags & VFCF_DELEGADMIN) && 498 mp->mnt_cred->cr_uid != td->td_ucred->cr_uid) { 499 if ((error = priv_check(td, PRIV_VFS_MOUNT_OWNER)) != 0) 500 return (error); 501 } 502 return (0); 503 } 504 505 /* 506 * Get a new unique fsid. Try to make its val[0] unique, since this value 507 * will be used to create fake device numbers for stat(). Also try (but 508 * not so hard) make its val[0] unique mod 2^16, since some emulators only 509 * support 16-bit device numbers. We end up with unique val[0]'s for the 510 * first 2^16 calls and unique val[0]'s mod 2^16 for the first 2^8 calls. 511 * 512 * Keep in mind that several mounts may be running in parallel. Starting 513 * the search one past where the previous search terminated is both a 514 * micro-optimization and a defense against returning the same fsid to 515 * different mounts. 516 */ 517 void 518 vfs_getnewfsid(struct mount *mp) 519 { 520 static uint16_t mntid_base; 521 struct mount *nmp; 522 fsid_t tfsid; 523 int mtype; 524 525 CTR2(KTR_VFS, "%s: mp %p", __func__, mp); 526 mtx_lock(&mntid_mtx); 527 mtype = mp->mnt_vfc->vfc_typenum; 528 tfsid.val[1] = mtype; 529 mtype = (mtype & 0xFF) << 24; 530 for (;;) { 531 tfsid.val[0] = makedev(255, 532 mtype | ((mntid_base & 0xFF00) << 8) | (mntid_base & 0xFF)); 533 mntid_base++; 534 if ((nmp = vfs_getvfs(&tfsid)) == NULL) 535 break; 536 vfs_rel(nmp); 537 } 538 mp->mnt_stat.f_fsid.val[0] = tfsid.val[0]; 539 mp->mnt_stat.f_fsid.val[1] = tfsid.val[1]; 540 mtx_unlock(&mntid_mtx); 541 } 542 543 /* 544 * Knob to control the precision of file timestamps: 545 * 546 * 0 = seconds only; nanoseconds zeroed. 547 * 1 = seconds and nanoseconds, accurate within 1/HZ. 548 * 2 = seconds and nanoseconds, truncated to microseconds. 549 * >=3 = seconds and nanoseconds, maximum precision. 550 */ 551 enum { TSP_SEC, TSP_HZ, TSP_USEC, TSP_NSEC }; 552 553 static int timestamp_precision = TSP_SEC; 554 SYSCTL_INT(_vfs, OID_AUTO, timestamp_precision, CTLFLAG_RW, 555 ×tamp_precision, 0, "File timestamp precision (0: seconds, " 556 "1: sec + ns accurate to 1/HZ, 2: sec + ns truncated to ms, " 557 "3+: sec + ns (max. precision))"); 558 559 /* 560 * Get a current timestamp. 561 */ 562 void 563 vfs_timestamp(struct timespec *tsp) 564 { 565 struct timeval tv; 566 567 switch (timestamp_precision) { 568 case TSP_SEC: 569 tsp->tv_sec = time_second; 570 tsp->tv_nsec = 0; 571 break; 572 case TSP_HZ: 573 getnanotime(tsp); 574 break; 575 case TSP_USEC: 576 microtime(&tv); 577 TIMEVAL_TO_TIMESPEC(&tv, tsp); 578 break; 579 case TSP_NSEC: 580 default: 581 nanotime(tsp); 582 break; 583 } 584 } 585 586 /* 587 * Set vnode attributes to VNOVAL 588 */ 589 void 590 vattr_null(struct vattr *vap) 591 { 592 593 vap->va_type = VNON; 594 vap->va_size = VNOVAL; 595 vap->va_bytes = VNOVAL; 596 vap->va_mode = VNOVAL; 597 vap->va_nlink = VNOVAL; 598 vap->va_uid = VNOVAL; 599 vap->va_gid = VNOVAL; 600 vap->va_fsid = VNOVAL; 601 vap->va_fileid = VNOVAL; 602 vap->va_blocksize = VNOVAL; 603 vap->va_rdev = VNOVAL; 604 vap->va_atime.tv_sec = VNOVAL; 605 vap->va_atime.tv_nsec = VNOVAL; 606 vap->va_mtime.tv_sec = VNOVAL; 607 vap->va_mtime.tv_nsec = VNOVAL; 608 vap->va_ctime.tv_sec = VNOVAL; 609 vap->va_ctime.tv_nsec = VNOVAL; 610 vap->va_birthtime.tv_sec = VNOVAL; 611 vap->va_birthtime.tv_nsec = VNOVAL; 612 vap->va_flags = VNOVAL; 613 vap->va_gen = VNOVAL; 614 vap->va_vaflags = 0; 615 } 616 617 /* 618 * This routine is called when we have too many vnodes. It attempts 619 * to free <count> vnodes and will potentially free vnodes that still 620 * have VM backing store (VM backing store is typically the cause 621 * of a vnode blowout so we want to do this). Therefore, this operation 622 * is not considered cheap. 623 * 624 * A number of conditions may prevent a vnode from being reclaimed. 625 * the buffer cache may have references on the vnode, a directory 626 * vnode may still have references due to the namei cache representing 627 * underlying files, or the vnode may be in active use. It is not 628 * desireable to reuse such vnodes. These conditions may cause the 629 * number of vnodes to reach some minimum value regardless of what 630 * you set kern.maxvnodes to. Do not set kern.maxvnodes too low. 631 */ 632 static int 633 vlrureclaim(struct mount *mp) 634 { 635 struct vnode *vp; 636 int done; 637 int trigger; 638 int usevnodes; 639 int count; 640 641 /* 642 * Calculate the trigger point, don't allow user 643 * screwups to blow us up. This prevents us from 644 * recycling vnodes with lots of resident pages. We 645 * aren't trying to free memory, we are trying to 646 * free vnodes. 647 */ 648 usevnodes = desiredvnodes; 649 if (usevnodes <= 0) 650 usevnodes = 1; 651 trigger = cnt.v_page_count * 2 / usevnodes; 652 done = 0; 653 vn_start_write(NULL, &mp, V_WAIT); 654 MNT_ILOCK(mp); 655 count = mp->mnt_nvnodelistsize / 10 + 1; 656 while (count != 0) { 657 vp = TAILQ_FIRST(&mp->mnt_nvnodelist); 658 while (vp != NULL && vp->v_type == VMARKER) 659 vp = TAILQ_NEXT(vp, v_nmntvnodes); 660 if (vp == NULL) 661 break; 662 TAILQ_REMOVE(&mp->mnt_nvnodelist, vp, v_nmntvnodes); 663 TAILQ_INSERT_TAIL(&mp->mnt_nvnodelist, vp, v_nmntvnodes); 664 --count; 665 if (!VI_TRYLOCK(vp)) 666 goto next_iter; 667 /* 668 * If it's been deconstructed already, it's still 669 * referenced, or it exceeds the trigger, skip it. 670 */ 671 if (vp->v_usecount || 672 (!vlru_allow_cache_src && 673 !LIST_EMPTY(&(vp)->v_cache_src)) || 674 (vp->v_iflag & VI_DOOMED) != 0 || (vp->v_object != NULL && 675 vp->v_object->resident_page_count > trigger)) { 676 VI_UNLOCK(vp); 677 goto next_iter; 678 } 679 MNT_IUNLOCK(mp); 680 vholdl(vp); 681 if (VOP_LOCK(vp, LK_INTERLOCK|LK_EXCLUSIVE|LK_NOWAIT)) { 682 vdrop(vp); 683 goto next_iter_mntunlocked; 684 } 685 VI_LOCK(vp); 686 /* 687 * v_usecount may have been bumped after VOP_LOCK() dropped 688 * the vnode interlock and before it was locked again. 689 * 690 * It is not necessary to recheck VI_DOOMED because it can 691 * only be set by another thread that holds both the vnode 692 * lock and vnode interlock. If another thread has the 693 * vnode lock before we get to VOP_LOCK() and obtains the 694 * vnode interlock after VOP_LOCK() drops the vnode 695 * interlock, the other thread will be unable to drop the 696 * vnode lock before our VOP_LOCK() call fails. 697 */ 698 if (vp->v_usecount || 699 (!vlru_allow_cache_src && 700 !LIST_EMPTY(&(vp)->v_cache_src)) || 701 (vp->v_object != NULL && 702 vp->v_object->resident_page_count > trigger)) { 703 VOP_UNLOCK(vp, LK_INTERLOCK); 704 goto next_iter_mntunlocked; 705 } 706 KASSERT((vp->v_iflag & VI_DOOMED) == 0, 707 ("VI_DOOMED unexpectedly detected in vlrureclaim()")); 708 vgonel(vp); 709 VOP_UNLOCK(vp, 0); 710 vdropl(vp); 711 done++; 712 next_iter_mntunlocked: 713 if (!should_yield()) 714 goto relock_mnt; 715 goto yield; 716 next_iter: 717 if (!should_yield()) 718 continue; 719 MNT_IUNLOCK(mp); 720 yield: 721 kern_yield(PRI_UNCHANGED); 722 relock_mnt: 723 MNT_ILOCK(mp); 724 } 725 MNT_IUNLOCK(mp); 726 vn_finished_write(mp); 727 return done; 728 } 729 730 /* 731 * Attempt to keep the free list at wantfreevnodes length. 732 */ 733 static void 734 vnlru_free(int count) 735 { 736 struct vnode *vp; 737 int vfslocked; 738 739 mtx_assert(&vnode_free_list_mtx, MA_OWNED); 740 for (; count > 0; count--) { 741 vp = TAILQ_FIRST(&vnode_free_list); 742 /* 743 * The list can be modified while the free_list_mtx 744 * has been dropped and vp could be NULL here. 745 */ 746 if (!vp) 747 break; 748 VNASSERT(vp->v_op != NULL, vp, 749 ("vnlru_free: vnode already reclaimed.")); 750 TAILQ_REMOVE(&vnode_free_list, vp, v_freelist); 751 /* 752 * Don't recycle if we can't get the interlock. 753 */ 754 if (!VI_TRYLOCK(vp)) { 755 TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_freelist); 756 continue; 757 } 758 VNASSERT(VCANRECYCLE(vp), vp, 759 ("vp inconsistent on freelist")); 760 freevnodes--; 761 vp->v_iflag &= ~VI_FREE; 762 vholdl(vp); 763 mtx_unlock(&vnode_free_list_mtx); 764 VI_UNLOCK(vp); 765 vfslocked = VFS_LOCK_GIANT(vp->v_mount); 766 vtryrecycle(vp); 767 VFS_UNLOCK_GIANT(vfslocked); 768 /* 769 * If the recycled succeeded this vdrop will actually free 770 * the vnode. If not it will simply place it back on 771 * the free list. 772 */ 773 vdrop(vp); 774 mtx_lock(&vnode_free_list_mtx); 775 } 776 } 777 /* 778 * Attempt to recycle vnodes in a context that is always safe to block. 779 * Calling vlrurecycle() from the bowels of filesystem code has some 780 * interesting deadlock problems. 781 */ 782 static struct proc *vnlruproc; 783 static int vnlruproc_sig; 784 785 static void 786 vnlru_proc(void) 787 { 788 struct mount *mp, *nmp; 789 int done, vfslocked; 790 struct proc *p = vnlruproc; 791 792 EVENTHANDLER_REGISTER(shutdown_pre_sync, kproc_shutdown, p, 793 SHUTDOWN_PRI_FIRST); 794 795 for (;;) { 796 kproc_suspend_check(p); 797 mtx_lock(&vnode_free_list_mtx); 798 if (freevnodes > wantfreevnodes) 799 vnlru_free(freevnodes - wantfreevnodes); 800 if (numvnodes <= desiredvnodes * 9 / 10) { 801 vnlruproc_sig = 0; 802 wakeup(&vnlruproc_sig); 803 msleep(vnlruproc, &vnode_free_list_mtx, 804 PVFS|PDROP, "vlruwt", hz); 805 continue; 806 } 807 mtx_unlock(&vnode_free_list_mtx); 808 done = 0; 809 mtx_lock(&mountlist_mtx); 810 for (mp = TAILQ_FIRST(&mountlist); mp != NULL; mp = nmp) { 811 if (vfs_busy(mp, MBF_NOWAIT | MBF_MNTLSTLOCK)) { 812 nmp = TAILQ_NEXT(mp, mnt_list); 813 continue; 814 } 815 vfslocked = VFS_LOCK_GIANT(mp); 816 done += vlrureclaim(mp); 817 VFS_UNLOCK_GIANT(vfslocked); 818 mtx_lock(&mountlist_mtx); 819 nmp = TAILQ_NEXT(mp, mnt_list); 820 vfs_unbusy(mp); 821 } 822 mtx_unlock(&mountlist_mtx); 823 if (done == 0) { 824 #if 0 825 /* These messages are temporary debugging aids */ 826 if (vnlru_nowhere < 5) 827 printf("vnlru process getting nowhere..\n"); 828 else if (vnlru_nowhere == 5) 829 printf("vnlru process messages stopped.\n"); 830 #endif 831 vnlru_nowhere++; 832 tsleep(vnlruproc, PPAUSE, "vlrup", hz * 3); 833 } else 834 kern_yield(PRI_UNCHANGED); 835 } 836 } 837 838 static struct kproc_desc vnlru_kp = { 839 "vnlru", 840 vnlru_proc, 841 &vnlruproc 842 }; 843 SYSINIT(vnlru, SI_SUB_KTHREAD_UPDATE, SI_ORDER_FIRST, kproc_start, 844 &vnlru_kp); 845 846 /* 847 * Routines having to do with the management of the vnode table. 848 */ 849 850 void 851 vdestroy(struct vnode *vp) 852 { 853 struct bufobj *bo; 854 855 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 856 mtx_lock(&vnode_free_list_mtx); 857 numvnodes--; 858 mtx_unlock(&vnode_free_list_mtx); 859 bo = &vp->v_bufobj; 860 VNASSERT((vp->v_iflag & VI_FREE) == 0, vp, 861 ("cleaned vnode still on the free list.")); 862 VNASSERT(vp->v_data == NULL, vp, ("cleaned vnode isn't")); 863 VNASSERT(vp->v_holdcnt == 0, vp, ("Non-zero hold count")); 864 VNASSERT(vp->v_usecount == 0, vp, ("Non-zero use count")); 865 VNASSERT(vp->v_writecount == 0, vp, ("Non-zero write count")); 866 VNASSERT(bo->bo_numoutput == 0, vp, ("Clean vnode has pending I/O's")); 867 VNASSERT(bo->bo_clean.bv_cnt == 0, vp, ("cleanbufcnt not 0")); 868 VNASSERT(bo->bo_clean.bv_root == NULL, vp, ("cleanblkroot not NULL")); 869 VNASSERT(bo->bo_dirty.bv_cnt == 0, vp, ("dirtybufcnt not 0")); 870 VNASSERT(bo->bo_dirty.bv_root == NULL, vp, ("dirtyblkroot not NULL")); 871 VNASSERT(TAILQ_EMPTY(&vp->v_cache_dst), vp, ("vp has namecache dst")); 872 VNASSERT(LIST_EMPTY(&vp->v_cache_src), vp, ("vp has namecache src")); 873 VNASSERT(vp->v_cache_dd == NULL, vp, ("vp has namecache for ..")); 874 VI_UNLOCK(vp); 875 #ifdef MAC 876 mac_vnode_destroy(vp); 877 #endif 878 if (vp->v_pollinfo != NULL) 879 destroy_vpollinfo(vp->v_pollinfo); 880 #ifdef INVARIANTS 881 /* XXX Elsewhere we can detect an already freed vnode via NULL v_op. */ 882 vp->v_op = NULL; 883 #endif 884 lockdestroy(vp->v_vnlock); 885 mtx_destroy(&vp->v_interlock); 886 mtx_destroy(BO_MTX(bo)); 887 uma_zfree(vnode_zone, vp); 888 } 889 890 /* 891 * Try to recycle a freed vnode. We abort if anyone picks up a reference 892 * before we actually vgone(). This function must be called with the vnode 893 * held to prevent the vnode from being returned to the free list midway 894 * through vgone(). 895 */ 896 static int 897 vtryrecycle(struct vnode *vp) 898 { 899 struct mount *vnmp; 900 901 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 902 VNASSERT(vp->v_holdcnt, vp, 903 ("vtryrecycle: Recycling vp %p without a reference.", vp)); 904 /* 905 * This vnode may found and locked via some other list, if so we 906 * can't recycle it yet. 907 */ 908 if (VOP_LOCK(vp, LK_EXCLUSIVE | LK_NOWAIT) != 0) { 909 CTR2(KTR_VFS, 910 "%s: impossible to recycle, vp %p lock is already held", 911 __func__, vp); 912 return (EWOULDBLOCK); 913 } 914 /* 915 * Don't recycle if its filesystem is being suspended. 916 */ 917 if (vn_start_write(vp, &vnmp, V_NOWAIT) != 0) { 918 VOP_UNLOCK(vp, 0); 919 CTR2(KTR_VFS, 920 "%s: impossible to recycle, cannot start the write for %p", 921 __func__, vp); 922 return (EBUSY); 923 } 924 /* 925 * If we got this far, we need to acquire the interlock and see if 926 * anyone picked up this vnode from another list. If not, we will 927 * mark it with DOOMED via vgonel() so that anyone who does find it 928 * will skip over it. 929 */ 930 VI_LOCK(vp); 931 if (vp->v_usecount) { 932 VOP_UNLOCK(vp, LK_INTERLOCK); 933 vn_finished_write(vnmp); 934 CTR2(KTR_VFS, 935 "%s: impossible to recycle, %p is already referenced", 936 __func__, vp); 937 return (EBUSY); 938 } 939 if ((vp->v_iflag & VI_DOOMED) == 0) 940 vgonel(vp); 941 VOP_UNLOCK(vp, LK_INTERLOCK); 942 vn_finished_write(vnmp); 943 return (0); 944 } 945 946 /* 947 * Return the next vnode from the free list. 948 */ 949 int 950 getnewvnode(const char *tag, struct mount *mp, struct vop_vector *vops, 951 struct vnode **vpp) 952 { 953 struct vnode *vp = NULL; 954 struct bufobj *bo; 955 956 CTR3(KTR_VFS, "%s: mp %p with tag %s", __func__, mp, tag); 957 mtx_lock(&vnode_free_list_mtx); 958 /* 959 * Lend our context to reclaim vnodes if they've exceeded the max. 960 */ 961 if (freevnodes > wantfreevnodes) 962 vnlru_free(1); 963 /* 964 * Wait for available vnodes. 965 */ 966 if (numvnodes > desiredvnodes) { 967 if (mp != NULL && (mp->mnt_kern_flag & MNTK_SUSPEND)) { 968 /* 969 * File system is beeing suspended, we cannot risk a 970 * deadlock here, so allocate new vnode anyway. 971 */ 972 if (freevnodes > wantfreevnodes) 973 vnlru_free(freevnodes - wantfreevnodes); 974 goto alloc; 975 } 976 if (vnlruproc_sig == 0) { 977 vnlruproc_sig = 1; /* avoid unnecessary wakeups */ 978 wakeup(vnlruproc); 979 } 980 msleep(&vnlruproc_sig, &vnode_free_list_mtx, PVFS, 981 "vlruwk", hz); 982 #if 0 /* XXX Not all VFS_VGET/ffs_vget callers check returns. */ 983 if (numvnodes > desiredvnodes) { 984 mtx_unlock(&vnode_free_list_mtx); 985 return (ENFILE); 986 } 987 #endif 988 } 989 alloc: 990 numvnodes++; 991 mtx_unlock(&vnode_free_list_mtx); 992 vp = (struct vnode *) uma_zalloc(vnode_zone, M_WAITOK|M_ZERO); 993 /* 994 * Setup locks. 995 */ 996 vp->v_vnlock = &vp->v_lock; 997 mtx_init(&vp->v_interlock, "vnode interlock", NULL, MTX_DEF); 998 /* 999 * By default, don't allow shared locks unless filesystems 1000 * opt-in. 1001 */ 1002 lockinit(vp->v_vnlock, PVFS, tag, VLKTIMEOUT, LK_NOSHARE); 1003 /* 1004 * Initialize bufobj. 1005 */ 1006 bo = &vp->v_bufobj; 1007 bo->__bo_vnode = vp; 1008 mtx_init(BO_MTX(bo), "bufobj interlock", NULL, MTX_DEF); 1009 bo->bo_ops = &buf_ops_bio; 1010 bo->bo_private = vp; 1011 TAILQ_INIT(&bo->bo_clean.bv_hd); 1012 TAILQ_INIT(&bo->bo_dirty.bv_hd); 1013 /* 1014 * Initialize namecache. 1015 */ 1016 LIST_INIT(&vp->v_cache_src); 1017 TAILQ_INIT(&vp->v_cache_dst); 1018 /* 1019 * Finalize various vnode identity bits. 1020 */ 1021 vp->v_type = VNON; 1022 vp->v_tag = tag; 1023 vp->v_op = vops; 1024 v_incr_usecount(vp); 1025 vp->v_data = 0; 1026 #ifdef MAC 1027 mac_vnode_init(vp); 1028 if (mp != NULL && (mp->mnt_flag & MNT_MULTILABEL) == 0) 1029 mac_vnode_associate_singlelabel(mp, vp); 1030 else if (mp == NULL && vops != &dead_vnodeops) 1031 printf("NULL mp in getnewvnode()\n"); 1032 #endif 1033 if (mp != NULL) { 1034 bo->bo_bsize = mp->mnt_stat.f_iosize; 1035 if ((mp->mnt_kern_flag & MNTK_NOKNOTE) != 0) 1036 vp->v_vflag |= VV_NOKNOTE; 1037 } 1038 1039 *vpp = vp; 1040 return (0); 1041 } 1042 1043 /* 1044 * Delete from old mount point vnode list, if on one. 1045 */ 1046 static void 1047 delmntque(struct vnode *vp) 1048 { 1049 struct mount *mp; 1050 1051 mp = vp->v_mount; 1052 if (mp == NULL) 1053 return; 1054 MNT_ILOCK(mp); 1055 vp->v_mount = NULL; 1056 VNASSERT(mp->mnt_nvnodelistsize > 0, vp, 1057 ("bad mount point vnode list size")); 1058 TAILQ_REMOVE(&mp->mnt_nvnodelist, vp, v_nmntvnodes); 1059 mp->mnt_nvnodelistsize--; 1060 MNT_REL(mp); 1061 MNT_IUNLOCK(mp); 1062 } 1063 1064 static void 1065 insmntque_stddtr(struct vnode *vp, void *dtr_arg) 1066 { 1067 1068 vp->v_data = NULL; 1069 vp->v_op = &dead_vnodeops; 1070 /* XXX non mp-safe fs may still call insmntque with vnode 1071 unlocked */ 1072 if (!VOP_ISLOCKED(vp)) 1073 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 1074 vgone(vp); 1075 vput(vp); 1076 } 1077 1078 /* 1079 * Insert into list of vnodes for the new mount point, if available. 1080 */ 1081 int 1082 insmntque1(struct vnode *vp, struct mount *mp, 1083 void (*dtr)(struct vnode *, void *), void *dtr_arg) 1084 { 1085 int locked; 1086 1087 KASSERT(vp->v_mount == NULL, 1088 ("insmntque: vnode already on per mount vnode list")); 1089 VNASSERT(mp != NULL, vp, ("Don't call insmntque(foo, NULL)")); 1090 #ifdef DEBUG_VFS_LOCKS 1091 if (!VFS_NEEDSGIANT(mp)) 1092 ASSERT_VOP_ELOCKED(vp, 1093 "insmntque: mp-safe fs and non-locked vp"); 1094 #endif 1095 MNT_ILOCK(mp); 1096 if ((mp->mnt_kern_flag & MNTK_NOINSMNTQ) != 0 && 1097 ((mp->mnt_kern_flag & MNTK_UNMOUNTF) != 0 || 1098 mp->mnt_nvnodelistsize == 0)) { 1099 locked = VOP_ISLOCKED(vp); 1100 if (!locked || (locked == LK_EXCLUSIVE && 1101 (vp->v_vflag & VV_FORCEINSMQ) == 0)) { 1102 MNT_IUNLOCK(mp); 1103 if (dtr != NULL) 1104 dtr(vp, dtr_arg); 1105 return (EBUSY); 1106 } 1107 } 1108 vp->v_mount = mp; 1109 MNT_REF(mp); 1110 TAILQ_INSERT_TAIL(&mp->mnt_nvnodelist, vp, v_nmntvnodes); 1111 VNASSERT(mp->mnt_nvnodelistsize >= 0, vp, 1112 ("neg mount point vnode list size")); 1113 mp->mnt_nvnodelistsize++; 1114 MNT_IUNLOCK(mp); 1115 return (0); 1116 } 1117 1118 int 1119 insmntque(struct vnode *vp, struct mount *mp) 1120 { 1121 1122 return (insmntque1(vp, mp, insmntque_stddtr, NULL)); 1123 } 1124 1125 /* 1126 * Flush out and invalidate all buffers associated with a bufobj 1127 * Called with the underlying object locked. 1128 */ 1129 int 1130 bufobj_invalbuf(struct bufobj *bo, int flags, int slpflag, int slptimeo) 1131 { 1132 int error; 1133 1134 BO_LOCK(bo); 1135 if (flags & V_SAVE) { 1136 error = bufobj_wwait(bo, slpflag, slptimeo); 1137 if (error) { 1138 BO_UNLOCK(bo); 1139 return (error); 1140 } 1141 if (bo->bo_dirty.bv_cnt > 0) { 1142 BO_UNLOCK(bo); 1143 if ((error = BO_SYNC(bo, MNT_WAIT)) != 0) 1144 return (error); 1145 /* 1146 * XXX We could save a lock/unlock if this was only 1147 * enabled under INVARIANTS 1148 */ 1149 BO_LOCK(bo); 1150 if (bo->bo_numoutput > 0 || bo->bo_dirty.bv_cnt > 0) 1151 panic("vinvalbuf: dirty bufs"); 1152 } 1153 } 1154 /* 1155 * If you alter this loop please notice that interlock is dropped and 1156 * reacquired in flushbuflist. Special care is needed to ensure that 1157 * no race conditions occur from this. 1158 */ 1159 do { 1160 error = flushbuflist(&bo->bo_clean, 1161 flags, bo, slpflag, slptimeo); 1162 if (error == 0) 1163 error = flushbuflist(&bo->bo_dirty, 1164 flags, bo, slpflag, slptimeo); 1165 if (error != 0 && error != EAGAIN) { 1166 BO_UNLOCK(bo); 1167 return (error); 1168 } 1169 } while (error != 0); 1170 1171 /* 1172 * Wait for I/O to complete. XXX needs cleaning up. The vnode can 1173 * have write I/O in-progress but if there is a VM object then the 1174 * VM object can also have read-I/O in-progress. 1175 */ 1176 do { 1177 bufobj_wwait(bo, 0, 0); 1178 BO_UNLOCK(bo); 1179 if (bo->bo_object != NULL) { 1180 VM_OBJECT_LOCK(bo->bo_object); 1181 vm_object_pip_wait(bo->bo_object, "bovlbx"); 1182 VM_OBJECT_UNLOCK(bo->bo_object); 1183 } 1184 BO_LOCK(bo); 1185 } while (bo->bo_numoutput > 0); 1186 BO_UNLOCK(bo); 1187 1188 /* 1189 * Destroy the copy in the VM cache, too. 1190 */ 1191 if (bo->bo_object != NULL && (flags & (V_ALT | V_NORMAL)) == 0) { 1192 VM_OBJECT_LOCK(bo->bo_object); 1193 vm_object_page_remove(bo->bo_object, 0, 0, 1194 (flags & V_SAVE) ? TRUE : FALSE); 1195 VM_OBJECT_UNLOCK(bo->bo_object); 1196 } 1197 1198 #ifdef INVARIANTS 1199 BO_LOCK(bo); 1200 if ((flags & (V_ALT | V_NORMAL)) == 0 && 1201 (bo->bo_dirty.bv_cnt > 0 || bo->bo_clean.bv_cnt > 0)) 1202 panic("vinvalbuf: flush failed"); 1203 BO_UNLOCK(bo); 1204 #endif 1205 return (0); 1206 } 1207 1208 /* 1209 * Flush out and invalidate all buffers associated with a vnode. 1210 * Called with the underlying object locked. 1211 */ 1212 int 1213 vinvalbuf(struct vnode *vp, int flags, int slpflag, int slptimeo) 1214 { 1215 1216 CTR3(KTR_VFS, "%s: vp %p with flags %d", __func__, vp, flags); 1217 ASSERT_VOP_LOCKED(vp, "vinvalbuf"); 1218 return (bufobj_invalbuf(&vp->v_bufobj, flags, slpflag, slptimeo)); 1219 } 1220 1221 /* 1222 * Flush out buffers on the specified list. 1223 * 1224 */ 1225 static int 1226 flushbuflist( struct bufv *bufv, int flags, struct bufobj *bo, int slpflag, 1227 int slptimeo) 1228 { 1229 struct buf *bp, *nbp; 1230 int retval, error; 1231 daddr_t lblkno; 1232 b_xflags_t xflags; 1233 1234 ASSERT_BO_LOCKED(bo); 1235 1236 retval = 0; 1237 TAILQ_FOREACH_SAFE(bp, &bufv->bv_hd, b_bobufs, nbp) { 1238 if (((flags & V_NORMAL) && (bp->b_xflags & BX_ALTDATA)) || 1239 ((flags & V_ALT) && (bp->b_xflags & BX_ALTDATA) == 0)) { 1240 continue; 1241 } 1242 lblkno = 0; 1243 xflags = 0; 1244 if (nbp != NULL) { 1245 lblkno = nbp->b_lblkno; 1246 xflags = nbp->b_xflags & 1247 (BX_BKGRDMARKER | BX_VNDIRTY | BX_VNCLEAN); 1248 } 1249 retval = EAGAIN; 1250 error = BUF_TIMELOCK(bp, 1251 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, BO_MTX(bo), 1252 "flushbuf", slpflag, slptimeo); 1253 if (error) { 1254 BO_LOCK(bo); 1255 return (error != ENOLCK ? error : EAGAIN); 1256 } 1257 KASSERT(bp->b_bufobj == bo, 1258 ("bp %p wrong b_bufobj %p should be %p", 1259 bp, bp->b_bufobj, bo)); 1260 if (bp->b_bufobj != bo) { /* XXX: necessary ? */ 1261 BUF_UNLOCK(bp); 1262 BO_LOCK(bo); 1263 return (EAGAIN); 1264 } 1265 /* 1266 * XXX Since there are no node locks for NFS, I 1267 * believe there is a slight chance that a delayed 1268 * write will occur while sleeping just above, so 1269 * check for it. 1270 */ 1271 if (((bp->b_flags & (B_DELWRI | B_INVAL)) == B_DELWRI) && 1272 (flags & V_SAVE)) { 1273 BO_LOCK(bo); 1274 bremfree(bp); 1275 BO_UNLOCK(bo); 1276 bp->b_flags |= B_ASYNC; 1277 bwrite(bp); 1278 BO_LOCK(bo); 1279 return (EAGAIN); /* XXX: why not loop ? */ 1280 } 1281 BO_LOCK(bo); 1282 bremfree(bp); 1283 BO_UNLOCK(bo); 1284 bp->b_flags |= (B_INVAL | B_RELBUF); 1285 bp->b_flags &= ~B_ASYNC; 1286 brelse(bp); 1287 BO_LOCK(bo); 1288 if (nbp != NULL && 1289 (nbp->b_bufobj != bo || 1290 nbp->b_lblkno != lblkno || 1291 (nbp->b_xflags & 1292 (BX_BKGRDMARKER | BX_VNDIRTY | BX_VNCLEAN)) != xflags)) 1293 break; /* nbp invalid */ 1294 } 1295 return (retval); 1296 } 1297 1298 /* 1299 * Truncate a file's buffer and pages to a specified length. This 1300 * is in lieu of the old vinvalbuf mechanism, which performed unneeded 1301 * sync activity. 1302 */ 1303 int 1304 vtruncbuf(struct vnode *vp, struct ucred *cred, struct thread *td, 1305 off_t length, int blksize) 1306 { 1307 struct buf *bp, *nbp; 1308 int anyfreed; 1309 int trunclbn; 1310 struct bufobj *bo; 1311 1312 CTR5(KTR_VFS, "%s: vp %p with cred %p and block %d:%ju", __func__, 1313 vp, cred, blksize, (uintmax_t)length); 1314 1315 /* 1316 * Round up to the *next* lbn. 1317 */ 1318 trunclbn = (length + blksize - 1) / blksize; 1319 1320 ASSERT_VOP_LOCKED(vp, "vtruncbuf"); 1321 restart: 1322 bo = &vp->v_bufobj; 1323 BO_LOCK(bo); 1324 anyfreed = 1; 1325 for (;anyfreed;) { 1326 anyfreed = 0; 1327 TAILQ_FOREACH_SAFE(bp, &bo->bo_clean.bv_hd, b_bobufs, nbp) { 1328 if (bp->b_lblkno < trunclbn) 1329 continue; 1330 if (BUF_LOCK(bp, 1331 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, 1332 BO_MTX(bo)) == ENOLCK) 1333 goto restart; 1334 1335 BO_LOCK(bo); 1336 bremfree(bp); 1337 BO_UNLOCK(bo); 1338 bp->b_flags |= (B_INVAL | B_RELBUF); 1339 bp->b_flags &= ~B_ASYNC; 1340 brelse(bp); 1341 anyfreed = 1; 1342 1343 BO_LOCK(bo); 1344 if (nbp != NULL && 1345 (((nbp->b_xflags & BX_VNCLEAN) == 0) || 1346 (nbp->b_vp != vp) || 1347 (nbp->b_flags & B_DELWRI))) { 1348 BO_UNLOCK(bo); 1349 goto restart; 1350 } 1351 } 1352 1353 TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) { 1354 if (bp->b_lblkno < trunclbn) 1355 continue; 1356 if (BUF_LOCK(bp, 1357 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, 1358 BO_MTX(bo)) == ENOLCK) 1359 goto restart; 1360 BO_LOCK(bo); 1361 bremfree(bp); 1362 BO_UNLOCK(bo); 1363 bp->b_flags |= (B_INVAL | B_RELBUF); 1364 bp->b_flags &= ~B_ASYNC; 1365 brelse(bp); 1366 anyfreed = 1; 1367 1368 BO_LOCK(bo); 1369 if (nbp != NULL && 1370 (((nbp->b_xflags & BX_VNDIRTY) == 0) || 1371 (nbp->b_vp != vp) || 1372 (nbp->b_flags & B_DELWRI) == 0)) { 1373 BO_UNLOCK(bo); 1374 goto restart; 1375 } 1376 } 1377 } 1378 1379 if (length > 0) { 1380 restartsync: 1381 TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) { 1382 if (bp->b_lblkno > 0) 1383 continue; 1384 /* 1385 * Since we hold the vnode lock this should only 1386 * fail if we're racing with the buf daemon. 1387 */ 1388 if (BUF_LOCK(bp, 1389 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, 1390 BO_MTX(bo)) == ENOLCK) { 1391 goto restart; 1392 } 1393 VNASSERT((bp->b_flags & B_DELWRI), vp, 1394 ("buf(%p) on dirty queue without DELWRI", bp)); 1395 1396 BO_LOCK(bo); 1397 bremfree(bp); 1398 BO_UNLOCK(bo); 1399 bawrite(bp); 1400 BO_LOCK(bo); 1401 goto restartsync; 1402 } 1403 } 1404 1405 bufobj_wwait(bo, 0, 0); 1406 BO_UNLOCK(bo); 1407 vnode_pager_setsize(vp, length); 1408 1409 return (0); 1410 } 1411 1412 /* 1413 * buf_splay() - splay tree core for the clean/dirty list of buffers in 1414 * a vnode. 1415 * 1416 * NOTE: We have to deal with the special case of a background bitmap 1417 * buffer, a situation where two buffers will have the same logical 1418 * block offset. We want (1) only the foreground buffer to be accessed 1419 * in a lookup and (2) must differentiate between the foreground and 1420 * background buffer in the splay tree algorithm because the splay 1421 * tree cannot normally handle multiple entities with the same 'index'. 1422 * We accomplish this by adding differentiating flags to the splay tree's 1423 * numerical domain. 1424 */ 1425 static 1426 struct buf * 1427 buf_splay(daddr_t lblkno, b_xflags_t xflags, struct buf *root) 1428 { 1429 struct buf dummy; 1430 struct buf *lefttreemax, *righttreemin, *y; 1431 1432 if (root == NULL) 1433 return (NULL); 1434 lefttreemax = righttreemin = &dummy; 1435 for (;;) { 1436 if (lblkno < root->b_lblkno || 1437 (lblkno == root->b_lblkno && 1438 (xflags & BX_BKGRDMARKER) < (root->b_xflags & BX_BKGRDMARKER))) { 1439 if ((y = root->b_left) == NULL) 1440 break; 1441 if (lblkno < y->b_lblkno) { 1442 /* Rotate right. */ 1443 root->b_left = y->b_right; 1444 y->b_right = root; 1445 root = y; 1446 if ((y = root->b_left) == NULL) 1447 break; 1448 } 1449 /* Link into the new root's right tree. */ 1450 righttreemin->b_left = root; 1451 righttreemin = root; 1452 } else if (lblkno > root->b_lblkno || 1453 (lblkno == root->b_lblkno && 1454 (xflags & BX_BKGRDMARKER) > (root->b_xflags & BX_BKGRDMARKER))) { 1455 if ((y = root->b_right) == NULL) 1456 break; 1457 if (lblkno > y->b_lblkno) { 1458 /* Rotate left. */ 1459 root->b_right = y->b_left; 1460 y->b_left = root; 1461 root = y; 1462 if ((y = root->b_right) == NULL) 1463 break; 1464 } 1465 /* Link into the new root's left tree. */ 1466 lefttreemax->b_right = root; 1467 lefttreemax = root; 1468 } else { 1469 break; 1470 } 1471 root = y; 1472 } 1473 /* Assemble the new root. */ 1474 lefttreemax->b_right = root->b_left; 1475 righttreemin->b_left = root->b_right; 1476 root->b_left = dummy.b_right; 1477 root->b_right = dummy.b_left; 1478 return (root); 1479 } 1480 1481 static void 1482 buf_vlist_remove(struct buf *bp) 1483 { 1484 struct buf *root; 1485 struct bufv *bv; 1486 1487 KASSERT(bp->b_bufobj != NULL, ("No b_bufobj %p", bp)); 1488 ASSERT_BO_LOCKED(bp->b_bufobj); 1489 KASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) != 1490 (BX_VNDIRTY|BX_VNCLEAN), 1491 ("buf_vlist_remove: Buf %p is on two lists", bp)); 1492 if (bp->b_xflags & BX_VNDIRTY) 1493 bv = &bp->b_bufobj->bo_dirty; 1494 else 1495 bv = &bp->b_bufobj->bo_clean; 1496 if (bp != bv->bv_root) { 1497 root = buf_splay(bp->b_lblkno, bp->b_xflags, bv->bv_root); 1498 KASSERT(root == bp, ("splay lookup failed in remove")); 1499 } 1500 if (bp->b_left == NULL) { 1501 root = bp->b_right; 1502 } else { 1503 root = buf_splay(bp->b_lblkno, bp->b_xflags, bp->b_left); 1504 root->b_right = bp->b_right; 1505 } 1506 bv->bv_root = root; 1507 TAILQ_REMOVE(&bv->bv_hd, bp, b_bobufs); 1508 bv->bv_cnt--; 1509 bp->b_xflags &= ~(BX_VNDIRTY | BX_VNCLEAN); 1510 } 1511 1512 /* 1513 * Add the buffer to the sorted clean or dirty block list using a 1514 * splay tree algorithm. 1515 * 1516 * NOTE: xflags is passed as a constant, optimizing this inline function! 1517 */ 1518 static void 1519 buf_vlist_add(struct buf *bp, struct bufobj *bo, b_xflags_t xflags) 1520 { 1521 struct buf *root; 1522 struct bufv *bv; 1523 1524 ASSERT_BO_LOCKED(bo); 1525 KASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) == 0, 1526 ("buf_vlist_add: Buf %p has existing xflags %d", bp, bp->b_xflags)); 1527 bp->b_xflags |= xflags; 1528 if (xflags & BX_VNDIRTY) 1529 bv = &bo->bo_dirty; 1530 else 1531 bv = &bo->bo_clean; 1532 1533 root = buf_splay(bp->b_lblkno, bp->b_xflags, bv->bv_root); 1534 if (root == NULL) { 1535 bp->b_left = NULL; 1536 bp->b_right = NULL; 1537 TAILQ_INSERT_TAIL(&bv->bv_hd, bp, b_bobufs); 1538 } else if (bp->b_lblkno < root->b_lblkno || 1539 (bp->b_lblkno == root->b_lblkno && 1540 (bp->b_xflags & BX_BKGRDMARKER) < (root->b_xflags & BX_BKGRDMARKER))) { 1541 bp->b_left = root->b_left; 1542 bp->b_right = root; 1543 root->b_left = NULL; 1544 TAILQ_INSERT_BEFORE(root, bp, b_bobufs); 1545 } else { 1546 bp->b_right = root->b_right; 1547 bp->b_left = root; 1548 root->b_right = NULL; 1549 TAILQ_INSERT_AFTER(&bv->bv_hd, root, bp, b_bobufs); 1550 } 1551 bv->bv_cnt++; 1552 bv->bv_root = bp; 1553 } 1554 1555 /* 1556 * Lookup a buffer using the splay tree. Note that we specifically avoid 1557 * shadow buffers used in background bitmap writes. 1558 * 1559 * This code isn't quite efficient as it could be because we are maintaining 1560 * two sorted lists and do not know which list the block resides in. 1561 * 1562 * During a "make buildworld" the desired buffer is found at one of 1563 * the roots more than 60% of the time. Thus, checking both roots 1564 * before performing either splay eliminates unnecessary splays on the 1565 * first tree splayed. 1566 */ 1567 struct buf * 1568 gbincore(struct bufobj *bo, daddr_t lblkno) 1569 { 1570 struct buf *bp; 1571 1572 ASSERT_BO_LOCKED(bo); 1573 if ((bp = bo->bo_clean.bv_root) != NULL && 1574 bp->b_lblkno == lblkno && !(bp->b_xflags & BX_BKGRDMARKER)) 1575 return (bp); 1576 if ((bp = bo->bo_dirty.bv_root) != NULL && 1577 bp->b_lblkno == lblkno && !(bp->b_xflags & BX_BKGRDMARKER)) 1578 return (bp); 1579 if ((bp = bo->bo_clean.bv_root) != NULL) { 1580 bo->bo_clean.bv_root = bp = buf_splay(lblkno, 0, bp); 1581 if (bp->b_lblkno == lblkno && !(bp->b_xflags & BX_BKGRDMARKER)) 1582 return (bp); 1583 } 1584 if ((bp = bo->bo_dirty.bv_root) != NULL) { 1585 bo->bo_dirty.bv_root = bp = buf_splay(lblkno, 0, bp); 1586 if (bp->b_lblkno == lblkno && !(bp->b_xflags & BX_BKGRDMARKER)) 1587 return (bp); 1588 } 1589 return (NULL); 1590 } 1591 1592 /* 1593 * Associate a buffer with a vnode. 1594 */ 1595 void 1596 bgetvp(struct vnode *vp, struct buf *bp) 1597 { 1598 struct bufobj *bo; 1599 1600 bo = &vp->v_bufobj; 1601 ASSERT_BO_LOCKED(bo); 1602 VNASSERT(bp->b_vp == NULL, bp->b_vp, ("bgetvp: not free")); 1603 1604 CTR3(KTR_BUF, "bgetvp(%p) vp %p flags %X", bp, vp, bp->b_flags); 1605 VNASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) == 0, vp, 1606 ("bgetvp: bp already attached! %p", bp)); 1607 1608 vhold(vp); 1609 if (VFS_NEEDSGIANT(vp->v_mount) || bo->bo_flag & BO_NEEDSGIANT) 1610 bp->b_flags |= B_NEEDSGIANT; 1611 bp->b_vp = vp; 1612 bp->b_bufobj = bo; 1613 /* 1614 * Insert onto list for new vnode. 1615 */ 1616 buf_vlist_add(bp, bo, BX_VNCLEAN); 1617 } 1618 1619 /* 1620 * Disassociate a buffer from a vnode. 1621 */ 1622 void 1623 brelvp(struct buf *bp) 1624 { 1625 struct bufobj *bo; 1626 struct vnode *vp; 1627 1628 CTR3(KTR_BUF, "brelvp(%p) vp %p flags %X", bp, bp->b_vp, bp->b_flags); 1629 KASSERT(bp->b_vp != NULL, ("brelvp: NULL")); 1630 1631 /* 1632 * Delete from old vnode list, if on one. 1633 */ 1634 vp = bp->b_vp; /* XXX */ 1635 bo = bp->b_bufobj; 1636 BO_LOCK(bo); 1637 if (bp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN)) 1638 buf_vlist_remove(bp); 1639 else 1640 panic("brelvp: Buffer %p not on queue.", bp); 1641 if ((bo->bo_flag & BO_ONWORKLST) && bo->bo_dirty.bv_cnt == 0) { 1642 bo->bo_flag &= ~BO_ONWORKLST; 1643 mtx_lock(&sync_mtx); 1644 LIST_REMOVE(bo, bo_synclist); 1645 syncer_worklist_len--; 1646 mtx_unlock(&sync_mtx); 1647 } 1648 bp->b_flags &= ~B_NEEDSGIANT; 1649 bp->b_vp = NULL; 1650 bp->b_bufobj = NULL; 1651 BO_UNLOCK(bo); 1652 vdrop(vp); 1653 } 1654 1655 /* 1656 * Add an item to the syncer work queue. 1657 */ 1658 static void 1659 vn_syncer_add_to_worklist(struct bufobj *bo, int delay) 1660 { 1661 int queue, slot; 1662 1663 ASSERT_BO_LOCKED(bo); 1664 1665 mtx_lock(&sync_mtx); 1666 if (bo->bo_flag & BO_ONWORKLST) 1667 LIST_REMOVE(bo, bo_synclist); 1668 else { 1669 bo->bo_flag |= BO_ONWORKLST; 1670 syncer_worklist_len++; 1671 } 1672 1673 if (delay > syncer_maxdelay - 2) 1674 delay = syncer_maxdelay - 2; 1675 slot = (syncer_delayno + delay) & syncer_mask; 1676 1677 queue = VFS_NEEDSGIANT(bo->__bo_vnode->v_mount) ? WI_GIANTQ : 1678 WI_MPSAFEQ; 1679 LIST_INSERT_HEAD(&syncer_workitem_pending[queue][slot], bo, 1680 bo_synclist); 1681 mtx_unlock(&sync_mtx); 1682 } 1683 1684 static int 1685 sysctl_vfs_worklist_len(SYSCTL_HANDLER_ARGS) 1686 { 1687 int error, len; 1688 1689 mtx_lock(&sync_mtx); 1690 len = syncer_worklist_len - sync_vnode_count; 1691 mtx_unlock(&sync_mtx); 1692 error = SYSCTL_OUT(req, &len, sizeof(len)); 1693 return (error); 1694 } 1695 1696 SYSCTL_PROC(_vfs, OID_AUTO, worklist_len, CTLTYPE_INT | CTLFLAG_RD, NULL, 0, 1697 sysctl_vfs_worklist_len, "I", "Syncer thread worklist length"); 1698 1699 static struct proc *updateproc; 1700 static void sched_sync(void); 1701 static struct kproc_desc up_kp = { 1702 "syncer", 1703 sched_sync, 1704 &updateproc 1705 }; 1706 SYSINIT(syncer, SI_SUB_KTHREAD_UPDATE, SI_ORDER_FIRST, kproc_start, &up_kp); 1707 1708 static int 1709 sync_vnode(struct synclist *slp, struct bufobj **bo, struct thread *td) 1710 { 1711 struct vnode *vp; 1712 struct mount *mp; 1713 1714 *bo = LIST_FIRST(slp); 1715 if (*bo == NULL) 1716 return (0); 1717 vp = (*bo)->__bo_vnode; /* XXX */ 1718 if (VOP_ISLOCKED(vp) != 0 || VI_TRYLOCK(vp) == 0) 1719 return (1); 1720 /* 1721 * We use vhold in case the vnode does not 1722 * successfully sync. vhold prevents the vnode from 1723 * going away when we unlock the sync_mtx so that 1724 * we can acquire the vnode interlock. 1725 */ 1726 vholdl(vp); 1727 mtx_unlock(&sync_mtx); 1728 VI_UNLOCK(vp); 1729 if (vn_start_write(vp, &mp, V_NOWAIT) != 0) { 1730 vdrop(vp); 1731 mtx_lock(&sync_mtx); 1732 return (*bo == LIST_FIRST(slp)); 1733 } 1734 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 1735 (void) VOP_FSYNC(vp, MNT_LAZY, td); 1736 VOP_UNLOCK(vp, 0); 1737 vn_finished_write(mp); 1738 BO_LOCK(*bo); 1739 if (((*bo)->bo_flag & BO_ONWORKLST) != 0) { 1740 /* 1741 * Put us back on the worklist. The worklist 1742 * routine will remove us from our current 1743 * position and then add us back in at a later 1744 * position. 1745 */ 1746 vn_syncer_add_to_worklist(*bo, syncdelay); 1747 } 1748 BO_UNLOCK(*bo); 1749 vdrop(vp); 1750 mtx_lock(&sync_mtx); 1751 return (0); 1752 } 1753 1754 /* 1755 * System filesystem synchronizer daemon. 1756 */ 1757 static void 1758 sched_sync(void) 1759 { 1760 struct synclist *gnext, *next; 1761 struct synclist *gslp, *slp; 1762 struct bufobj *bo; 1763 long starttime; 1764 struct thread *td = curthread; 1765 int last_work_seen; 1766 int net_worklist_len; 1767 int syncer_final_iter; 1768 int first_printf; 1769 int error; 1770 1771 last_work_seen = 0; 1772 syncer_final_iter = 0; 1773 first_printf = 1; 1774 syncer_state = SYNCER_RUNNING; 1775 starttime = time_uptime; 1776 td->td_pflags |= TDP_NORUNNINGBUF; 1777 1778 EVENTHANDLER_REGISTER(shutdown_pre_sync, syncer_shutdown, td->td_proc, 1779 SHUTDOWN_PRI_LAST); 1780 1781 mtx_lock(&sync_mtx); 1782 for (;;) { 1783 if (syncer_state == SYNCER_FINAL_DELAY && 1784 syncer_final_iter == 0) { 1785 mtx_unlock(&sync_mtx); 1786 kproc_suspend_check(td->td_proc); 1787 mtx_lock(&sync_mtx); 1788 } 1789 net_worklist_len = syncer_worklist_len - sync_vnode_count; 1790 if (syncer_state != SYNCER_RUNNING && 1791 starttime != time_uptime) { 1792 if (first_printf) { 1793 printf("\nSyncing disks, vnodes remaining..."); 1794 first_printf = 0; 1795 } 1796 printf("%d ", net_worklist_len); 1797 } 1798 starttime = time_uptime; 1799 1800 /* 1801 * Push files whose dirty time has expired. Be careful 1802 * of interrupt race on slp queue. 1803 * 1804 * Skip over empty worklist slots when shutting down. 1805 */ 1806 do { 1807 slp = &syncer_workitem_pending[WI_MPSAFEQ][syncer_delayno]; 1808 gslp = &syncer_workitem_pending[WI_GIANTQ][syncer_delayno]; 1809 syncer_delayno += 1; 1810 if (syncer_delayno == syncer_maxdelay) 1811 syncer_delayno = 0; 1812 next = &syncer_workitem_pending[WI_MPSAFEQ][syncer_delayno]; 1813 gnext = &syncer_workitem_pending[WI_GIANTQ][syncer_delayno]; 1814 /* 1815 * If the worklist has wrapped since the 1816 * it was emptied of all but syncer vnodes, 1817 * switch to the FINAL_DELAY state and run 1818 * for one more second. 1819 */ 1820 if (syncer_state == SYNCER_SHUTTING_DOWN && 1821 net_worklist_len == 0 && 1822 last_work_seen == syncer_delayno) { 1823 syncer_state = SYNCER_FINAL_DELAY; 1824 syncer_final_iter = SYNCER_SHUTDOWN_SPEEDUP; 1825 } 1826 } while (syncer_state != SYNCER_RUNNING && LIST_EMPTY(slp) && 1827 LIST_EMPTY(gslp) && syncer_worklist_len > 0); 1828 1829 /* 1830 * Keep track of the last time there was anything 1831 * on the worklist other than syncer vnodes. 1832 * Return to the SHUTTING_DOWN state if any 1833 * new work appears. 1834 */ 1835 if (net_worklist_len > 0 || syncer_state == SYNCER_RUNNING) 1836 last_work_seen = syncer_delayno; 1837 if (net_worklist_len > 0 && syncer_state == SYNCER_FINAL_DELAY) 1838 syncer_state = SYNCER_SHUTTING_DOWN; 1839 while (!LIST_EMPTY(slp)) { 1840 error = sync_vnode(slp, &bo, td); 1841 if (error == 1) { 1842 LIST_REMOVE(bo, bo_synclist); 1843 LIST_INSERT_HEAD(next, bo, bo_synclist); 1844 continue; 1845 } 1846 #ifdef SW_WATCHDOG 1847 if (first_printf == 0) 1848 wdog_kern_pat(WD_LASTVAL); 1849 #endif 1850 } 1851 if (!LIST_EMPTY(gslp)) { 1852 mtx_unlock(&sync_mtx); 1853 mtx_lock(&Giant); 1854 mtx_lock(&sync_mtx); 1855 while (!LIST_EMPTY(gslp)) { 1856 error = sync_vnode(gslp, &bo, td); 1857 if (error == 1) { 1858 LIST_REMOVE(bo, bo_synclist); 1859 LIST_INSERT_HEAD(gnext, bo, 1860 bo_synclist); 1861 continue; 1862 } 1863 } 1864 mtx_unlock(&Giant); 1865 } 1866 if (syncer_state == SYNCER_FINAL_DELAY && syncer_final_iter > 0) 1867 syncer_final_iter--; 1868 /* 1869 * The variable rushjob allows the kernel to speed up the 1870 * processing of the filesystem syncer process. A rushjob 1871 * value of N tells the filesystem syncer to process the next 1872 * N seconds worth of work on its queue ASAP. Currently rushjob 1873 * is used by the soft update code to speed up the filesystem 1874 * syncer process when the incore state is getting so far 1875 * ahead of the disk that the kernel memory pool is being 1876 * threatened with exhaustion. 1877 */ 1878 if (rushjob > 0) { 1879 rushjob -= 1; 1880 continue; 1881 } 1882 /* 1883 * Just sleep for a short period of time between 1884 * iterations when shutting down to allow some I/O 1885 * to happen. 1886 * 1887 * If it has taken us less than a second to process the 1888 * current work, then wait. Otherwise start right over 1889 * again. We can still lose time if any single round 1890 * takes more than two seconds, but it does not really 1891 * matter as we are just trying to generally pace the 1892 * filesystem activity. 1893 */ 1894 if (syncer_state != SYNCER_RUNNING || 1895 time_uptime == starttime) { 1896 thread_lock(td); 1897 sched_prio(td, PPAUSE); 1898 thread_unlock(td); 1899 } 1900 if (syncer_state != SYNCER_RUNNING) 1901 cv_timedwait(&sync_wakeup, &sync_mtx, 1902 hz / SYNCER_SHUTDOWN_SPEEDUP); 1903 else if (time_uptime == starttime) 1904 cv_timedwait(&sync_wakeup, &sync_mtx, hz); 1905 } 1906 } 1907 1908 /* 1909 * Request the syncer daemon to speed up its work. 1910 * We never push it to speed up more than half of its 1911 * normal turn time, otherwise it could take over the cpu. 1912 */ 1913 int 1914 speedup_syncer(void) 1915 { 1916 int ret = 0; 1917 1918 mtx_lock(&sync_mtx); 1919 if (rushjob < syncdelay / 2) { 1920 rushjob += 1; 1921 stat_rush_requests += 1; 1922 ret = 1; 1923 } 1924 mtx_unlock(&sync_mtx); 1925 cv_broadcast(&sync_wakeup); 1926 return (ret); 1927 } 1928 1929 /* 1930 * Tell the syncer to speed up its work and run though its work 1931 * list several times, then tell it to shut down. 1932 */ 1933 static void 1934 syncer_shutdown(void *arg, int howto) 1935 { 1936 1937 if (howto & RB_NOSYNC) 1938 return; 1939 mtx_lock(&sync_mtx); 1940 syncer_state = SYNCER_SHUTTING_DOWN; 1941 rushjob = 0; 1942 mtx_unlock(&sync_mtx); 1943 cv_broadcast(&sync_wakeup); 1944 kproc_shutdown(arg, howto); 1945 } 1946 1947 /* 1948 * Reassign a buffer from one vnode to another. 1949 * Used to assign file specific control information 1950 * (indirect blocks) to the vnode to which they belong. 1951 */ 1952 void 1953 reassignbuf(struct buf *bp) 1954 { 1955 struct vnode *vp; 1956 struct bufobj *bo; 1957 int delay; 1958 #ifdef INVARIANTS 1959 struct bufv *bv; 1960 #endif 1961 1962 vp = bp->b_vp; 1963 bo = bp->b_bufobj; 1964 ++reassignbufcalls; 1965 1966 CTR3(KTR_BUF, "reassignbuf(%p) vp %p flags %X", 1967 bp, bp->b_vp, bp->b_flags); 1968 /* 1969 * B_PAGING flagged buffers cannot be reassigned because their vp 1970 * is not fully linked in. 1971 */ 1972 if (bp->b_flags & B_PAGING) 1973 panic("cannot reassign paging buffer"); 1974 1975 /* 1976 * Delete from old vnode list, if on one. 1977 */ 1978 BO_LOCK(bo); 1979 if (bp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN)) 1980 buf_vlist_remove(bp); 1981 else 1982 panic("reassignbuf: Buffer %p not on queue.", bp); 1983 /* 1984 * If dirty, put on list of dirty buffers; otherwise insert onto list 1985 * of clean buffers. 1986 */ 1987 if (bp->b_flags & B_DELWRI) { 1988 if ((bo->bo_flag & BO_ONWORKLST) == 0) { 1989 switch (vp->v_type) { 1990 case VDIR: 1991 delay = dirdelay; 1992 break; 1993 case VCHR: 1994 delay = metadelay; 1995 break; 1996 default: 1997 delay = filedelay; 1998 } 1999 vn_syncer_add_to_worklist(bo, delay); 2000 } 2001 buf_vlist_add(bp, bo, BX_VNDIRTY); 2002 } else { 2003 buf_vlist_add(bp, bo, BX_VNCLEAN); 2004 2005 if ((bo->bo_flag & BO_ONWORKLST) && bo->bo_dirty.bv_cnt == 0) { 2006 mtx_lock(&sync_mtx); 2007 LIST_REMOVE(bo, bo_synclist); 2008 syncer_worklist_len--; 2009 mtx_unlock(&sync_mtx); 2010 bo->bo_flag &= ~BO_ONWORKLST; 2011 } 2012 } 2013 #ifdef INVARIANTS 2014 bv = &bo->bo_clean; 2015 bp = TAILQ_FIRST(&bv->bv_hd); 2016 KASSERT(bp == NULL || bp->b_bufobj == bo, 2017 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 2018 bp = TAILQ_LAST(&bv->bv_hd, buflists); 2019 KASSERT(bp == NULL || bp->b_bufobj == bo, 2020 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 2021 bv = &bo->bo_dirty; 2022 bp = TAILQ_FIRST(&bv->bv_hd); 2023 KASSERT(bp == NULL || bp->b_bufobj == bo, 2024 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 2025 bp = TAILQ_LAST(&bv->bv_hd, buflists); 2026 KASSERT(bp == NULL || bp->b_bufobj == bo, 2027 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 2028 #endif 2029 BO_UNLOCK(bo); 2030 } 2031 2032 /* 2033 * Increment the use and hold counts on the vnode, taking care to reference 2034 * the driver's usecount if this is a chardev. The vholdl() will remove 2035 * the vnode from the free list if it is presently free. Requires the 2036 * vnode interlock and returns with it held. 2037 */ 2038 static void 2039 v_incr_usecount(struct vnode *vp) 2040 { 2041 2042 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2043 vp->v_usecount++; 2044 if (vp->v_type == VCHR && vp->v_rdev != NULL) { 2045 dev_lock(); 2046 vp->v_rdev->si_usecount++; 2047 dev_unlock(); 2048 } 2049 vholdl(vp); 2050 } 2051 2052 /* 2053 * Turn a holdcnt into a use+holdcnt such that only one call to 2054 * v_decr_usecount is needed. 2055 */ 2056 static void 2057 v_upgrade_usecount(struct vnode *vp) 2058 { 2059 2060 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2061 vp->v_usecount++; 2062 if (vp->v_type == VCHR && vp->v_rdev != NULL) { 2063 dev_lock(); 2064 vp->v_rdev->si_usecount++; 2065 dev_unlock(); 2066 } 2067 } 2068 2069 /* 2070 * Decrement the vnode use and hold count along with the driver's usecount 2071 * if this is a chardev. The vdropl() below releases the vnode interlock 2072 * as it may free the vnode. 2073 */ 2074 static void 2075 v_decr_usecount(struct vnode *vp) 2076 { 2077 2078 ASSERT_VI_LOCKED(vp, __FUNCTION__); 2079 VNASSERT(vp->v_usecount > 0, vp, 2080 ("v_decr_usecount: negative usecount")); 2081 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2082 vp->v_usecount--; 2083 if (vp->v_type == VCHR && vp->v_rdev != NULL) { 2084 dev_lock(); 2085 vp->v_rdev->si_usecount--; 2086 dev_unlock(); 2087 } 2088 vdropl(vp); 2089 } 2090 2091 /* 2092 * Decrement only the use count and driver use count. This is intended to 2093 * be paired with a follow on vdropl() to release the remaining hold count. 2094 * In this way we may vgone() a vnode with a 0 usecount without risk of 2095 * having it end up on a free list because the hold count is kept above 0. 2096 */ 2097 static void 2098 v_decr_useonly(struct vnode *vp) 2099 { 2100 2101 ASSERT_VI_LOCKED(vp, __FUNCTION__); 2102 VNASSERT(vp->v_usecount > 0, vp, 2103 ("v_decr_useonly: negative usecount")); 2104 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2105 vp->v_usecount--; 2106 if (vp->v_type == VCHR && vp->v_rdev != NULL) { 2107 dev_lock(); 2108 vp->v_rdev->si_usecount--; 2109 dev_unlock(); 2110 } 2111 } 2112 2113 /* 2114 * Grab a particular vnode from the free list, increment its 2115 * reference count and lock it. VI_DOOMED is set if the vnode 2116 * is being destroyed. Only callers who specify LK_RETRY will 2117 * see doomed vnodes. If inactive processing was delayed in 2118 * vput try to do it here. 2119 */ 2120 int 2121 vget(struct vnode *vp, int flags, struct thread *td) 2122 { 2123 int error; 2124 2125 error = 0; 2126 VFS_ASSERT_GIANT(vp->v_mount); 2127 VNASSERT((flags & LK_TYPE_MASK) != 0, vp, 2128 ("vget: invalid lock operation")); 2129 CTR3(KTR_VFS, "%s: vp %p with flags %d", __func__, vp, flags); 2130 2131 if ((flags & LK_INTERLOCK) == 0) 2132 VI_LOCK(vp); 2133 vholdl(vp); 2134 if ((error = vn_lock(vp, flags | LK_INTERLOCK)) != 0) { 2135 vdrop(vp); 2136 CTR2(KTR_VFS, "%s: impossible to lock vnode %p", __func__, 2137 vp); 2138 return (error); 2139 } 2140 if (vp->v_iflag & VI_DOOMED && (flags & LK_RETRY) == 0) 2141 panic("vget: vn_lock failed to return ENOENT\n"); 2142 VI_LOCK(vp); 2143 /* Upgrade our holdcnt to a usecount. */ 2144 v_upgrade_usecount(vp); 2145 /* 2146 * We don't guarantee that any particular close will 2147 * trigger inactive processing so just make a best effort 2148 * here at preventing a reference to a removed file. If 2149 * we don't succeed no harm is done. 2150 */ 2151 if (vp->v_iflag & VI_OWEINACT) { 2152 if (VOP_ISLOCKED(vp) == LK_EXCLUSIVE && 2153 (flags & LK_NOWAIT) == 0) 2154 vinactive(vp, td); 2155 vp->v_iflag &= ~VI_OWEINACT; 2156 } 2157 VI_UNLOCK(vp); 2158 return (0); 2159 } 2160 2161 /* 2162 * Increase the reference count of a vnode. 2163 */ 2164 void 2165 vref(struct vnode *vp) 2166 { 2167 2168 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2169 VI_LOCK(vp); 2170 v_incr_usecount(vp); 2171 VI_UNLOCK(vp); 2172 } 2173 2174 /* 2175 * Return reference count of a vnode. 2176 * 2177 * The results of this call are only guaranteed when some mechanism other 2178 * than the VI lock is used to stop other processes from gaining references 2179 * to the vnode. This may be the case if the caller holds the only reference. 2180 * This is also useful when stale data is acceptable as race conditions may 2181 * be accounted for by some other means. 2182 */ 2183 int 2184 vrefcnt(struct vnode *vp) 2185 { 2186 int usecnt; 2187 2188 VI_LOCK(vp); 2189 usecnt = vp->v_usecount; 2190 VI_UNLOCK(vp); 2191 2192 return (usecnt); 2193 } 2194 2195 #define VPUTX_VRELE 1 2196 #define VPUTX_VPUT 2 2197 #define VPUTX_VUNREF 3 2198 2199 static void 2200 vputx(struct vnode *vp, int func) 2201 { 2202 int error; 2203 2204 KASSERT(vp != NULL, ("vputx: null vp")); 2205 if (func == VPUTX_VUNREF) 2206 ASSERT_VOP_LOCKED(vp, "vunref"); 2207 else if (func == VPUTX_VPUT) 2208 ASSERT_VOP_LOCKED(vp, "vput"); 2209 else 2210 KASSERT(func == VPUTX_VRELE, ("vputx: wrong func")); 2211 VFS_ASSERT_GIANT(vp->v_mount); 2212 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2213 VI_LOCK(vp); 2214 2215 /* Skip this v_writecount check if we're going to panic below. */ 2216 VNASSERT(vp->v_writecount < vp->v_usecount || vp->v_usecount < 1, vp, 2217 ("vputx: missed vn_close")); 2218 error = 0; 2219 2220 if (vp->v_usecount > 1 || ((vp->v_iflag & VI_DOINGINACT) && 2221 vp->v_usecount == 1)) { 2222 if (func == VPUTX_VPUT) 2223 VOP_UNLOCK(vp, 0); 2224 v_decr_usecount(vp); 2225 return; 2226 } 2227 2228 if (vp->v_usecount != 1) { 2229 vprint("vputx: negative ref count", vp); 2230 panic("vputx: negative ref cnt"); 2231 } 2232 CTR2(KTR_VFS, "%s: return vnode %p to the freelist", __func__, vp); 2233 /* 2234 * We want to hold the vnode until the inactive finishes to 2235 * prevent vgone() races. We drop the use count here and the 2236 * hold count below when we're done. 2237 */ 2238 v_decr_useonly(vp); 2239 /* 2240 * We must call VOP_INACTIVE with the node locked. Mark 2241 * as VI_DOINGINACT to avoid recursion. 2242 */ 2243 vp->v_iflag |= VI_OWEINACT; 2244 switch (func) { 2245 case VPUTX_VRELE: 2246 error = vn_lock(vp, LK_EXCLUSIVE | LK_INTERLOCK); 2247 VI_LOCK(vp); 2248 break; 2249 case VPUTX_VPUT: 2250 if (VOP_ISLOCKED(vp) != LK_EXCLUSIVE) { 2251 error = VOP_LOCK(vp, LK_UPGRADE | LK_INTERLOCK | 2252 LK_NOWAIT); 2253 VI_LOCK(vp); 2254 } 2255 break; 2256 case VPUTX_VUNREF: 2257 if (VOP_ISLOCKED(vp) != LK_EXCLUSIVE) 2258 error = EBUSY; 2259 break; 2260 } 2261 if (vp->v_usecount > 0) 2262 vp->v_iflag &= ~VI_OWEINACT; 2263 if (error == 0) { 2264 if (vp->v_iflag & VI_OWEINACT) 2265 vinactive(vp, curthread); 2266 if (func != VPUTX_VUNREF) 2267 VOP_UNLOCK(vp, 0); 2268 } 2269 vdropl(vp); 2270 } 2271 2272 /* 2273 * Vnode put/release. 2274 * If count drops to zero, call inactive routine and return to freelist. 2275 */ 2276 void 2277 vrele(struct vnode *vp) 2278 { 2279 2280 vputx(vp, VPUTX_VRELE); 2281 } 2282 2283 /* 2284 * Release an already locked vnode. This give the same effects as 2285 * unlock+vrele(), but takes less time and avoids releasing and 2286 * re-aquiring the lock (as vrele() acquires the lock internally.) 2287 */ 2288 void 2289 vput(struct vnode *vp) 2290 { 2291 2292 vputx(vp, VPUTX_VPUT); 2293 } 2294 2295 /* 2296 * Release an exclusively locked vnode. Do not unlock the vnode lock. 2297 */ 2298 void 2299 vunref(struct vnode *vp) 2300 { 2301 2302 vputx(vp, VPUTX_VUNREF); 2303 } 2304 2305 /* 2306 * Somebody doesn't want the vnode recycled. 2307 */ 2308 void 2309 vhold(struct vnode *vp) 2310 { 2311 2312 VI_LOCK(vp); 2313 vholdl(vp); 2314 VI_UNLOCK(vp); 2315 } 2316 2317 void 2318 vholdl(struct vnode *vp) 2319 { 2320 2321 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2322 vp->v_holdcnt++; 2323 if (VSHOULDBUSY(vp)) 2324 vbusy(vp); 2325 } 2326 2327 /* 2328 * Note that there is one less who cares about this vnode. vdrop() is the 2329 * opposite of vhold(). 2330 */ 2331 void 2332 vdrop(struct vnode *vp) 2333 { 2334 2335 VI_LOCK(vp); 2336 vdropl(vp); 2337 } 2338 2339 /* 2340 * Drop the hold count of the vnode. If this is the last reference to 2341 * the vnode we will free it if it has been vgone'd otherwise it is 2342 * placed on the free list. 2343 */ 2344 void 2345 vdropl(struct vnode *vp) 2346 { 2347 2348 ASSERT_VI_LOCKED(vp, "vdropl"); 2349 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2350 if (vp->v_holdcnt <= 0) 2351 panic("vdrop: holdcnt %d", vp->v_holdcnt); 2352 vp->v_holdcnt--; 2353 if (vp->v_holdcnt == 0) { 2354 if (vp->v_iflag & VI_DOOMED) { 2355 CTR2(KTR_VFS, "%s: destroying the vnode %p", __func__, 2356 vp); 2357 vdestroy(vp); 2358 return; 2359 } else 2360 vfree(vp); 2361 } 2362 VI_UNLOCK(vp); 2363 } 2364 2365 /* 2366 * Call VOP_INACTIVE on the vnode and manage the DOINGINACT and OWEINACT 2367 * flags. DOINGINACT prevents us from recursing in calls to vinactive. 2368 * OWEINACT tracks whether a vnode missed a call to inactive due to a 2369 * failed lock upgrade. 2370 */ 2371 static void 2372 vinactive(struct vnode *vp, struct thread *td) 2373 { 2374 2375 ASSERT_VOP_ELOCKED(vp, "vinactive"); 2376 ASSERT_VI_LOCKED(vp, "vinactive"); 2377 VNASSERT((vp->v_iflag & VI_DOINGINACT) == 0, vp, 2378 ("vinactive: recursed on VI_DOINGINACT")); 2379 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2380 vp->v_iflag |= VI_DOINGINACT; 2381 vp->v_iflag &= ~VI_OWEINACT; 2382 VI_UNLOCK(vp); 2383 VOP_INACTIVE(vp, td); 2384 VI_LOCK(vp); 2385 VNASSERT(vp->v_iflag & VI_DOINGINACT, vp, 2386 ("vinactive: lost VI_DOINGINACT")); 2387 vp->v_iflag &= ~VI_DOINGINACT; 2388 } 2389 2390 /* 2391 * Remove any vnodes in the vnode table belonging to mount point mp. 2392 * 2393 * If FORCECLOSE is not specified, there should not be any active ones, 2394 * return error if any are found (nb: this is a user error, not a 2395 * system error). If FORCECLOSE is specified, detach any active vnodes 2396 * that are found. 2397 * 2398 * If WRITECLOSE is set, only flush out regular file vnodes open for 2399 * writing. 2400 * 2401 * SKIPSYSTEM causes any vnodes marked VV_SYSTEM to be skipped. 2402 * 2403 * `rootrefs' specifies the base reference count for the root vnode 2404 * of this filesystem. The root vnode is considered busy if its 2405 * v_usecount exceeds this value. On a successful return, vflush(, td) 2406 * will call vrele() on the root vnode exactly rootrefs times. 2407 * If the SKIPSYSTEM or WRITECLOSE flags are specified, rootrefs must 2408 * be zero. 2409 */ 2410 #ifdef DIAGNOSTIC 2411 static int busyprt = 0; /* print out busy vnodes */ 2412 SYSCTL_INT(_debug, OID_AUTO, busyprt, CTLFLAG_RW, &busyprt, 0, "Print out busy vnodes"); 2413 #endif 2414 2415 int 2416 vflush(struct mount *mp, int rootrefs, int flags, struct thread *td) 2417 { 2418 struct vnode *vp, *mvp, *rootvp = NULL; 2419 struct vattr vattr; 2420 int busy = 0, error; 2421 2422 CTR4(KTR_VFS, "%s: mp %p with rootrefs %d and flags %d", __func__, mp, 2423 rootrefs, flags); 2424 if (rootrefs > 0) { 2425 KASSERT((flags & (SKIPSYSTEM | WRITECLOSE)) == 0, 2426 ("vflush: bad args")); 2427 /* 2428 * Get the filesystem root vnode. We can vput() it 2429 * immediately, since with rootrefs > 0, it won't go away. 2430 */ 2431 if ((error = VFS_ROOT(mp, LK_EXCLUSIVE, &rootvp)) != 0) { 2432 CTR2(KTR_VFS, "%s: vfs_root lookup failed with %d", 2433 __func__, error); 2434 return (error); 2435 } 2436 vput(rootvp); 2437 } 2438 MNT_ILOCK(mp); 2439 loop: 2440 MNT_VNODE_FOREACH(vp, mp, mvp) { 2441 VI_LOCK(vp); 2442 vholdl(vp); 2443 MNT_IUNLOCK(mp); 2444 error = vn_lock(vp, LK_INTERLOCK | LK_EXCLUSIVE); 2445 if (error) { 2446 vdrop(vp); 2447 MNT_ILOCK(mp); 2448 MNT_VNODE_FOREACH_ABORT_ILOCKED(mp, mvp); 2449 goto loop; 2450 } 2451 /* 2452 * Skip over a vnodes marked VV_SYSTEM. 2453 */ 2454 if ((flags & SKIPSYSTEM) && (vp->v_vflag & VV_SYSTEM)) { 2455 VOP_UNLOCK(vp, 0); 2456 vdrop(vp); 2457 MNT_ILOCK(mp); 2458 continue; 2459 } 2460 /* 2461 * If WRITECLOSE is set, flush out unlinked but still open 2462 * files (even if open only for reading) and regular file 2463 * vnodes open for writing. 2464 */ 2465 if (flags & WRITECLOSE) { 2466 error = VOP_GETATTR(vp, &vattr, td->td_ucred); 2467 VI_LOCK(vp); 2468 2469 if ((vp->v_type == VNON || 2470 (error == 0 && vattr.va_nlink > 0)) && 2471 (vp->v_writecount == 0 || vp->v_type != VREG)) { 2472 VOP_UNLOCK(vp, 0); 2473 vdropl(vp); 2474 MNT_ILOCK(mp); 2475 continue; 2476 } 2477 } else 2478 VI_LOCK(vp); 2479 /* 2480 * With v_usecount == 0, all we need to do is clear out the 2481 * vnode data structures and we are done. 2482 * 2483 * If FORCECLOSE is set, forcibly close the vnode. 2484 */ 2485 if (vp->v_usecount == 0 || (flags & FORCECLOSE)) { 2486 VNASSERT(vp->v_usecount == 0 || 2487 (vp->v_type != VCHR && vp->v_type != VBLK), vp, 2488 ("device VNODE %p is FORCECLOSED", vp)); 2489 vgonel(vp); 2490 } else { 2491 busy++; 2492 #ifdef DIAGNOSTIC 2493 if (busyprt) 2494 vprint("vflush: busy vnode", vp); 2495 #endif 2496 } 2497 VOP_UNLOCK(vp, 0); 2498 vdropl(vp); 2499 MNT_ILOCK(mp); 2500 } 2501 MNT_IUNLOCK(mp); 2502 if (rootrefs > 0 && (flags & FORCECLOSE) == 0) { 2503 /* 2504 * If just the root vnode is busy, and if its refcount 2505 * is equal to `rootrefs', then go ahead and kill it. 2506 */ 2507 VI_LOCK(rootvp); 2508 KASSERT(busy > 0, ("vflush: not busy")); 2509 VNASSERT(rootvp->v_usecount >= rootrefs, rootvp, 2510 ("vflush: usecount %d < rootrefs %d", 2511 rootvp->v_usecount, rootrefs)); 2512 if (busy == 1 && rootvp->v_usecount == rootrefs) { 2513 VOP_LOCK(rootvp, LK_EXCLUSIVE|LK_INTERLOCK); 2514 vgone(rootvp); 2515 VOP_UNLOCK(rootvp, 0); 2516 busy = 0; 2517 } else 2518 VI_UNLOCK(rootvp); 2519 } 2520 if (busy) { 2521 CTR2(KTR_VFS, "%s: failing as %d vnodes are busy", __func__, 2522 busy); 2523 return (EBUSY); 2524 } 2525 for (; rootrefs > 0; rootrefs--) 2526 vrele(rootvp); 2527 return (0); 2528 } 2529 2530 /* 2531 * Recycle an unused vnode to the front of the free list. 2532 */ 2533 int 2534 vrecycle(struct vnode *vp, struct thread *td) 2535 { 2536 int recycled; 2537 2538 ASSERT_VOP_ELOCKED(vp, "vrecycle"); 2539 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2540 recycled = 0; 2541 VI_LOCK(vp); 2542 if (vp->v_usecount == 0) { 2543 recycled = 1; 2544 vgonel(vp); 2545 } 2546 VI_UNLOCK(vp); 2547 return (recycled); 2548 } 2549 2550 /* 2551 * Eliminate all activity associated with a vnode 2552 * in preparation for reuse. 2553 */ 2554 void 2555 vgone(struct vnode *vp) 2556 { 2557 VI_LOCK(vp); 2558 vgonel(vp); 2559 VI_UNLOCK(vp); 2560 } 2561 2562 /* 2563 * vgone, with the vp interlock held. 2564 */ 2565 void 2566 vgonel(struct vnode *vp) 2567 { 2568 struct thread *td; 2569 int oweinact; 2570 int active; 2571 struct mount *mp; 2572 2573 ASSERT_VOP_ELOCKED(vp, "vgonel"); 2574 ASSERT_VI_LOCKED(vp, "vgonel"); 2575 VNASSERT(vp->v_holdcnt, vp, 2576 ("vgonel: vp %p has no reference.", vp)); 2577 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2578 td = curthread; 2579 2580 /* 2581 * Don't vgonel if we're already doomed. 2582 */ 2583 if (vp->v_iflag & VI_DOOMED) 2584 return; 2585 vp->v_iflag |= VI_DOOMED; 2586 /* 2587 * Check to see if the vnode is in use. If so, we have to call 2588 * VOP_CLOSE() and VOP_INACTIVE(). 2589 */ 2590 active = vp->v_usecount; 2591 oweinact = (vp->v_iflag & VI_OWEINACT); 2592 VI_UNLOCK(vp); 2593 /* 2594 * Clean out any buffers associated with the vnode. 2595 * If the flush fails, just toss the buffers. 2596 */ 2597 mp = NULL; 2598 if (!TAILQ_EMPTY(&vp->v_bufobj.bo_dirty.bv_hd)) 2599 (void) vn_start_secondary_write(vp, &mp, V_WAIT); 2600 if (vinvalbuf(vp, V_SAVE, 0, 0) != 0) 2601 vinvalbuf(vp, 0, 0, 0); 2602 2603 /* 2604 * If purging an active vnode, it must be closed and 2605 * deactivated before being reclaimed. 2606 */ 2607 if (active) 2608 VOP_CLOSE(vp, FNONBLOCK, NOCRED, td); 2609 if (oweinact || active) { 2610 VI_LOCK(vp); 2611 if ((vp->v_iflag & VI_DOINGINACT) == 0) 2612 vinactive(vp, td); 2613 VI_UNLOCK(vp); 2614 } 2615 /* 2616 * Reclaim the vnode. 2617 */ 2618 if (VOP_RECLAIM(vp, td)) 2619 panic("vgone: cannot reclaim"); 2620 if (mp != NULL) 2621 vn_finished_secondary_write(mp); 2622 VNASSERT(vp->v_object == NULL, vp, 2623 ("vop_reclaim left v_object vp=%p, tag=%s", vp, vp->v_tag)); 2624 /* 2625 * Clear the advisory locks and wake up waiting threads. 2626 */ 2627 (void)VOP_ADVLOCKPURGE(vp); 2628 /* 2629 * Delete from old mount point vnode list. 2630 */ 2631 delmntque(vp); 2632 cache_purge(vp); 2633 /* 2634 * Done with purge, reset to the standard lock and invalidate 2635 * the vnode. 2636 */ 2637 VI_LOCK(vp); 2638 vp->v_vnlock = &vp->v_lock; 2639 vp->v_op = &dead_vnodeops; 2640 vp->v_tag = "none"; 2641 vp->v_type = VBAD; 2642 } 2643 2644 /* 2645 * Calculate the total number of references to a special device. 2646 */ 2647 int 2648 vcount(struct vnode *vp) 2649 { 2650 int count; 2651 2652 dev_lock(); 2653 count = vp->v_rdev->si_usecount; 2654 dev_unlock(); 2655 return (count); 2656 } 2657 2658 /* 2659 * Same as above, but using the struct cdev *as argument 2660 */ 2661 int 2662 count_dev(struct cdev *dev) 2663 { 2664 int count; 2665 2666 dev_lock(); 2667 count = dev->si_usecount; 2668 dev_unlock(); 2669 return(count); 2670 } 2671 2672 /* 2673 * Print out a description of a vnode. 2674 */ 2675 static char *typename[] = 2676 {"VNON", "VREG", "VDIR", "VBLK", "VCHR", "VLNK", "VSOCK", "VFIFO", "VBAD", 2677 "VMARKER"}; 2678 2679 void 2680 vn_printf(struct vnode *vp, const char *fmt, ...) 2681 { 2682 va_list ap; 2683 char buf[256], buf2[16]; 2684 u_long flags; 2685 2686 va_start(ap, fmt); 2687 vprintf(fmt, ap); 2688 va_end(ap); 2689 printf("%p: ", (void *)vp); 2690 printf("tag %s, type %s\n", vp->v_tag, typename[vp->v_type]); 2691 printf(" usecount %d, writecount %d, refcount %d mountedhere %p\n", 2692 vp->v_usecount, vp->v_writecount, vp->v_holdcnt, vp->v_mountedhere); 2693 buf[0] = '\0'; 2694 buf[1] = '\0'; 2695 if (vp->v_vflag & VV_ROOT) 2696 strlcat(buf, "|VV_ROOT", sizeof(buf)); 2697 if (vp->v_vflag & VV_ISTTY) 2698 strlcat(buf, "|VV_ISTTY", sizeof(buf)); 2699 if (vp->v_vflag & VV_NOSYNC) 2700 strlcat(buf, "|VV_NOSYNC", sizeof(buf)); 2701 if (vp->v_vflag & VV_CACHEDLABEL) 2702 strlcat(buf, "|VV_CACHEDLABEL", sizeof(buf)); 2703 if (vp->v_vflag & VV_TEXT) 2704 strlcat(buf, "|VV_TEXT", sizeof(buf)); 2705 if (vp->v_vflag & VV_COPYONWRITE) 2706 strlcat(buf, "|VV_COPYONWRITE", sizeof(buf)); 2707 if (vp->v_vflag & VV_SYSTEM) 2708 strlcat(buf, "|VV_SYSTEM", sizeof(buf)); 2709 if (vp->v_vflag & VV_PROCDEP) 2710 strlcat(buf, "|VV_PROCDEP", sizeof(buf)); 2711 if (vp->v_vflag & VV_NOKNOTE) 2712 strlcat(buf, "|VV_NOKNOTE", sizeof(buf)); 2713 if (vp->v_vflag & VV_DELETED) 2714 strlcat(buf, "|VV_DELETED", sizeof(buf)); 2715 if (vp->v_vflag & VV_MD) 2716 strlcat(buf, "|VV_MD", sizeof(buf)); 2717 flags = vp->v_vflag & ~(VV_ROOT | VV_ISTTY | VV_NOSYNC | 2718 VV_CACHEDLABEL | VV_TEXT | VV_COPYONWRITE | VV_SYSTEM | VV_PROCDEP | 2719 VV_NOKNOTE | VV_DELETED | VV_MD); 2720 if (flags != 0) { 2721 snprintf(buf2, sizeof(buf2), "|VV(0x%lx)", flags); 2722 strlcat(buf, buf2, sizeof(buf)); 2723 } 2724 if (vp->v_iflag & VI_MOUNT) 2725 strlcat(buf, "|VI_MOUNT", sizeof(buf)); 2726 if (vp->v_iflag & VI_AGE) 2727 strlcat(buf, "|VI_AGE", sizeof(buf)); 2728 if (vp->v_iflag & VI_DOOMED) 2729 strlcat(buf, "|VI_DOOMED", sizeof(buf)); 2730 if (vp->v_iflag & VI_FREE) 2731 strlcat(buf, "|VI_FREE", sizeof(buf)); 2732 if (vp->v_iflag & VI_DOINGINACT) 2733 strlcat(buf, "|VI_DOINGINACT", sizeof(buf)); 2734 if (vp->v_iflag & VI_OWEINACT) 2735 strlcat(buf, "|VI_OWEINACT", sizeof(buf)); 2736 flags = vp->v_iflag & ~(VI_MOUNT | VI_AGE | VI_DOOMED | VI_FREE | 2737 VI_DOINGINACT | VI_OWEINACT); 2738 if (flags != 0) { 2739 snprintf(buf2, sizeof(buf2), "|VI(0x%lx)", flags); 2740 strlcat(buf, buf2, sizeof(buf)); 2741 } 2742 printf(" flags (%s)\n", buf + 1); 2743 if (mtx_owned(VI_MTX(vp))) 2744 printf(" VI_LOCKed"); 2745 if (vp->v_object != NULL) 2746 printf(" v_object %p ref %d pages %d\n", 2747 vp->v_object, vp->v_object->ref_count, 2748 vp->v_object->resident_page_count); 2749 printf(" "); 2750 lockmgr_printinfo(vp->v_vnlock); 2751 if (vp->v_data != NULL) 2752 VOP_PRINT(vp); 2753 } 2754 2755 #ifdef DDB 2756 /* 2757 * List all of the locked vnodes in the system. 2758 * Called when debugging the kernel. 2759 */ 2760 DB_SHOW_COMMAND(lockedvnods, lockedvnodes) 2761 { 2762 struct mount *mp, *nmp; 2763 struct vnode *vp; 2764 2765 /* 2766 * Note: because this is DDB, we can't obey the locking semantics 2767 * for these structures, which means we could catch an inconsistent 2768 * state and dereference a nasty pointer. Not much to be done 2769 * about that. 2770 */ 2771 db_printf("Locked vnodes\n"); 2772 for (mp = TAILQ_FIRST(&mountlist); mp != NULL; mp = nmp) { 2773 nmp = TAILQ_NEXT(mp, mnt_list); 2774 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) { 2775 if (vp->v_type != VMARKER && 2776 VOP_ISLOCKED(vp)) 2777 vprint("", vp); 2778 } 2779 nmp = TAILQ_NEXT(mp, mnt_list); 2780 } 2781 } 2782 2783 /* 2784 * Show details about the given vnode. 2785 */ 2786 DB_SHOW_COMMAND(vnode, db_show_vnode) 2787 { 2788 struct vnode *vp; 2789 2790 if (!have_addr) 2791 return; 2792 vp = (struct vnode *)addr; 2793 vn_printf(vp, "vnode "); 2794 } 2795 2796 /* 2797 * Show details about the given mount point. 2798 */ 2799 DB_SHOW_COMMAND(mount, db_show_mount) 2800 { 2801 struct mount *mp; 2802 struct vfsopt *opt; 2803 struct statfs *sp; 2804 struct vnode *vp; 2805 char buf[512]; 2806 u_int flags; 2807 2808 if (!have_addr) { 2809 /* No address given, print short info about all mount points. */ 2810 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 2811 db_printf("%p %s on %s (%s)\n", mp, 2812 mp->mnt_stat.f_mntfromname, 2813 mp->mnt_stat.f_mntonname, 2814 mp->mnt_stat.f_fstypename); 2815 if (db_pager_quit) 2816 break; 2817 } 2818 db_printf("\nMore info: show mount <addr>\n"); 2819 return; 2820 } 2821 2822 mp = (struct mount *)addr; 2823 db_printf("%p %s on %s (%s)\n", mp, mp->mnt_stat.f_mntfromname, 2824 mp->mnt_stat.f_mntonname, mp->mnt_stat.f_fstypename); 2825 2826 buf[0] = '\0'; 2827 flags = mp->mnt_flag; 2828 #define MNT_FLAG(flag) do { \ 2829 if (flags & (flag)) { \ 2830 if (buf[0] != '\0') \ 2831 strlcat(buf, ", ", sizeof(buf)); \ 2832 strlcat(buf, (#flag) + 4, sizeof(buf)); \ 2833 flags &= ~(flag); \ 2834 } \ 2835 } while (0) 2836 MNT_FLAG(MNT_RDONLY); 2837 MNT_FLAG(MNT_SYNCHRONOUS); 2838 MNT_FLAG(MNT_NOEXEC); 2839 MNT_FLAG(MNT_NOSUID); 2840 MNT_FLAG(MNT_UNION); 2841 MNT_FLAG(MNT_ASYNC); 2842 MNT_FLAG(MNT_SUIDDIR); 2843 MNT_FLAG(MNT_SOFTDEP); 2844 MNT_FLAG(MNT_NOSYMFOLLOW); 2845 MNT_FLAG(MNT_GJOURNAL); 2846 MNT_FLAG(MNT_MULTILABEL); 2847 MNT_FLAG(MNT_ACLS); 2848 MNT_FLAG(MNT_NOATIME); 2849 MNT_FLAG(MNT_NOCLUSTERR); 2850 MNT_FLAG(MNT_NOCLUSTERW); 2851 MNT_FLAG(MNT_NFS4ACLS); 2852 MNT_FLAG(MNT_EXRDONLY); 2853 MNT_FLAG(MNT_EXPORTED); 2854 MNT_FLAG(MNT_DEFEXPORTED); 2855 MNT_FLAG(MNT_EXPORTANON); 2856 MNT_FLAG(MNT_EXKERB); 2857 MNT_FLAG(MNT_EXPUBLIC); 2858 MNT_FLAG(MNT_LOCAL); 2859 MNT_FLAG(MNT_QUOTA); 2860 MNT_FLAG(MNT_ROOTFS); 2861 MNT_FLAG(MNT_USER); 2862 MNT_FLAG(MNT_IGNORE); 2863 MNT_FLAG(MNT_UPDATE); 2864 MNT_FLAG(MNT_DELEXPORT); 2865 MNT_FLAG(MNT_RELOAD); 2866 MNT_FLAG(MNT_FORCE); 2867 MNT_FLAG(MNT_SNAPSHOT); 2868 MNT_FLAG(MNT_BYFSID); 2869 MNT_FLAG(MNT_SOFTDEP); 2870 #undef MNT_FLAG 2871 if (flags != 0) { 2872 if (buf[0] != '\0') 2873 strlcat(buf, ", ", sizeof(buf)); 2874 snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf), 2875 "0x%08x", flags); 2876 } 2877 db_printf(" mnt_flag = %s\n", buf); 2878 2879 buf[0] = '\0'; 2880 flags = mp->mnt_kern_flag; 2881 #define MNT_KERN_FLAG(flag) do { \ 2882 if (flags & (flag)) { \ 2883 if (buf[0] != '\0') \ 2884 strlcat(buf, ", ", sizeof(buf)); \ 2885 strlcat(buf, (#flag) + 5, sizeof(buf)); \ 2886 flags &= ~(flag); \ 2887 } \ 2888 } while (0) 2889 MNT_KERN_FLAG(MNTK_UNMOUNTF); 2890 MNT_KERN_FLAG(MNTK_ASYNC); 2891 MNT_KERN_FLAG(MNTK_SOFTDEP); 2892 MNT_KERN_FLAG(MNTK_NOINSMNTQ); 2893 MNT_KERN_FLAG(MNTK_DRAINING); 2894 MNT_KERN_FLAG(MNTK_REFEXPIRE); 2895 MNT_KERN_FLAG(MNTK_EXTENDED_SHARED); 2896 MNT_KERN_FLAG(MNTK_SHARED_WRITES); 2897 MNT_KERN_FLAG(MNTK_SUJ); 2898 MNT_KERN_FLAG(MNTK_UNMOUNT); 2899 MNT_KERN_FLAG(MNTK_MWAIT); 2900 MNT_KERN_FLAG(MNTK_SUSPEND); 2901 MNT_KERN_FLAG(MNTK_SUSPEND2); 2902 MNT_KERN_FLAG(MNTK_SUSPENDED); 2903 MNT_KERN_FLAG(MNTK_MPSAFE); 2904 MNT_KERN_FLAG(MNTK_LOOKUP_SHARED); 2905 MNT_KERN_FLAG(MNTK_NOKNOTE); 2906 #undef MNT_KERN_FLAG 2907 if (flags != 0) { 2908 if (buf[0] != '\0') 2909 strlcat(buf, ", ", sizeof(buf)); 2910 snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf), 2911 "0x%08x", flags); 2912 } 2913 db_printf(" mnt_kern_flag = %s\n", buf); 2914 2915 db_printf(" mnt_opt = "); 2916 opt = TAILQ_FIRST(mp->mnt_opt); 2917 if (opt != NULL) { 2918 db_printf("%s", opt->name); 2919 opt = TAILQ_NEXT(opt, link); 2920 while (opt != NULL) { 2921 db_printf(", %s", opt->name); 2922 opt = TAILQ_NEXT(opt, link); 2923 } 2924 } 2925 db_printf("\n"); 2926 2927 sp = &mp->mnt_stat; 2928 db_printf(" mnt_stat = { version=%u type=%u flags=0x%016jx " 2929 "bsize=%ju iosize=%ju blocks=%ju bfree=%ju bavail=%jd files=%ju " 2930 "ffree=%jd syncwrites=%ju asyncwrites=%ju syncreads=%ju " 2931 "asyncreads=%ju namemax=%u owner=%u fsid=[%d, %d] }\n", 2932 (u_int)sp->f_version, (u_int)sp->f_type, (uintmax_t)sp->f_flags, 2933 (uintmax_t)sp->f_bsize, (uintmax_t)sp->f_iosize, 2934 (uintmax_t)sp->f_blocks, (uintmax_t)sp->f_bfree, 2935 (intmax_t)sp->f_bavail, (uintmax_t)sp->f_files, 2936 (intmax_t)sp->f_ffree, (uintmax_t)sp->f_syncwrites, 2937 (uintmax_t)sp->f_asyncwrites, (uintmax_t)sp->f_syncreads, 2938 (uintmax_t)sp->f_asyncreads, (u_int)sp->f_namemax, 2939 (u_int)sp->f_owner, (int)sp->f_fsid.val[0], (int)sp->f_fsid.val[1]); 2940 2941 db_printf(" mnt_cred = { uid=%u ruid=%u", 2942 (u_int)mp->mnt_cred->cr_uid, (u_int)mp->mnt_cred->cr_ruid); 2943 if (jailed(mp->mnt_cred)) 2944 db_printf(", jail=%d", mp->mnt_cred->cr_prison->pr_id); 2945 db_printf(" }\n"); 2946 db_printf(" mnt_ref = %d\n", mp->mnt_ref); 2947 db_printf(" mnt_gen = %d\n", mp->mnt_gen); 2948 db_printf(" mnt_nvnodelistsize = %d\n", mp->mnt_nvnodelistsize); 2949 db_printf(" mnt_writeopcount = %d\n", mp->mnt_writeopcount); 2950 db_printf(" mnt_noasync = %u\n", mp->mnt_noasync); 2951 db_printf(" mnt_maxsymlinklen = %d\n", mp->mnt_maxsymlinklen); 2952 db_printf(" mnt_iosize_max = %d\n", mp->mnt_iosize_max); 2953 db_printf(" mnt_hashseed = %u\n", mp->mnt_hashseed); 2954 db_printf(" mnt_secondary_writes = %d\n", mp->mnt_secondary_writes); 2955 db_printf(" mnt_secondary_accwrites = %d\n", 2956 mp->mnt_secondary_accwrites); 2957 db_printf(" mnt_gjprovider = %s\n", 2958 mp->mnt_gjprovider != NULL ? mp->mnt_gjprovider : "NULL"); 2959 db_printf("\n"); 2960 2961 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) { 2962 if (vp->v_type != VMARKER) { 2963 vn_printf(vp, "vnode "); 2964 if (db_pager_quit) 2965 break; 2966 } 2967 } 2968 } 2969 #endif /* DDB */ 2970 2971 /* 2972 * Fill in a struct xvfsconf based on a struct vfsconf. 2973 */ 2974 static void 2975 vfsconf2x(struct vfsconf *vfsp, struct xvfsconf *xvfsp) 2976 { 2977 2978 strcpy(xvfsp->vfc_name, vfsp->vfc_name); 2979 xvfsp->vfc_typenum = vfsp->vfc_typenum; 2980 xvfsp->vfc_refcount = vfsp->vfc_refcount; 2981 xvfsp->vfc_flags = vfsp->vfc_flags; 2982 /* 2983 * These are unused in userland, we keep them 2984 * to not break binary compatibility. 2985 */ 2986 xvfsp->vfc_vfsops = NULL; 2987 xvfsp->vfc_next = NULL; 2988 } 2989 2990 /* 2991 * Top level filesystem related information gathering. 2992 */ 2993 static int 2994 sysctl_vfs_conflist(SYSCTL_HANDLER_ARGS) 2995 { 2996 struct vfsconf *vfsp; 2997 struct xvfsconf xvfsp; 2998 int error; 2999 3000 error = 0; 3001 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) { 3002 bzero(&xvfsp, sizeof(xvfsp)); 3003 vfsconf2x(vfsp, &xvfsp); 3004 error = SYSCTL_OUT(req, &xvfsp, sizeof xvfsp); 3005 if (error) 3006 break; 3007 } 3008 return (error); 3009 } 3010 3011 SYSCTL_PROC(_vfs, OID_AUTO, conflist, CTLTYPE_OPAQUE | CTLFLAG_RD, 3012 NULL, 0, sysctl_vfs_conflist, 3013 "S,xvfsconf", "List of all configured filesystems"); 3014 3015 #ifndef BURN_BRIDGES 3016 static int sysctl_ovfs_conf(SYSCTL_HANDLER_ARGS); 3017 3018 static int 3019 vfs_sysctl(SYSCTL_HANDLER_ARGS) 3020 { 3021 int *name = (int *)arg1 - 1; /* XXX */ 3022 u_int namelen = arg2 + 1; /* XXX */ 3023 struct vfsconf *vfsp; 3024 struct xvfsconf xvfsp; 3025 3026 printf("WARNING: userland calling deprecated sysctl, " 3027 "please rebuild world\n"); 3028 3029 #if 1 || defined(COMPAT_PRELITE2) 3030 /* Resolve ambiguity between VFS_VFSCONF and VFS_GENERIC. */ 3031 if (namelen == 1) 3032 return (sysctl_ovfs_conf(oidp, arg1, arg2, req)); 3033 #endif 3034 3035 switch (name[1]) { 3036 case VFS_MAXTYPENUM: 3037 if (namelen != 2) 3038 return (ENOTDIR); 3039 return (SYSCTL_OUT(req, &maxvfsconf, sizeof(int))); 3040 case VFS_CONF: 3041 if (namelen != 3) 3042 return (ENOTDIR); /* overloaded */ 3043 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) 3044 if (vfsp->vfc_typenum == name[2]) 3045 break; 3046 if (vfsp == NULL) 3047 return (EOPNOTSUPP); 3048 bzero(&xvfsp, sizeof(xvfsp)); 3049 vfsconf2x(vfsp, &xvfsp); 3050 return (SYSCTL_OUT(req, &xvfsp, sizeof(xvfsp))); 3051 } 3052 return (EOPNOTSUPP); 3053 } 3054 3055 static SYSCTL_NODE(_vfs, VFS_GENERIC, generic, CTLFLAG_RD | CTLFLAG_SKIP, 3056 vfs_sysctl, "Generic filesystem"); 3057 3058 #if 1 || defined(COMPAT_PRELITE2) 3059 3060 static int 3061 sysctl_ovfs_conf(SYSCTL_HANDLER_ARGS) 3062 { 3063 int error; 3064 struct vfsconf *vfsp; 3065 struct ovfsconf ovfs; 3066 3067 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) { 3068 bzero(&ovfs, sizeof(ovfs)); 3069 ovfs.vfc_vfsops = vfsp->vfc_vfsops; /* XXX used as flag */ 3070 strcpy(ovfs.vfc_name, vfsp->vfc_name); 3071 ovfs.vfc_index = vfsp->vfc_typenum; 3072 ovfs.vfc_refcount = vfsp->vfc_refcount; 3073 ovfs.vfc_flags = vfsp->vfc_flags; 3074 error = SYSCTL_OUT(req, &ovfs, sizeof ovfs); 3075 if (error) 3076 return error; 3077 } 3078 return 0; 3079 } 3080 3081 #endif /* 1 || COMPAT_PRELITE2 */ 3082 #endif /* !BURN_BRIDGES */ 3083 3084 #define KINFO_VNODESLOP 10 3085 #ifdef notyet 3086 /* 3087 * Dump vnode list (via sysctl). 3088 */ 3089 /* ARGSUSED */ 3090 static int 3091 sysctl_vnode(SYSCTL_HANDLER_ARGS) 3092 { 3093 struct xvnode *xvn; 3094 struct mount *mp; 3095 struct vnode *vp; 3096 int error, len, n; 3097 3098 /* 3099 * Stale numvnodes access is not fatal here. 3100 */ 3101 req->lock = 0; 3102 len = (numvnodes + KINFO_VNODESLOP) * sizeof *xvn; 3103 if (!req->oldptr) 3104 /* Make an estimate */ 3105 return (SYSCTL_OUT(req, 0, len)); 3106 3107 error = sysctl_wire_old_buffer(req, 0); 3108 if (error != 0) 3109 return (error); 3110 xvn = malloc(len, M_TEMP, M_ZERO | M_WAITOK); 3111 n = 0; 3112 mtx_lock(&mountlist_mtx); 3113 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 3114 if (vfs_busy(mp, MBF_NOWAIT | MBF_MNTLSTLOCK)) 3115 continue; 3116 MNT_ILOCK(mp); 3117 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) { 3118 if (n == len) 3119 break; 3120 vref(vp); 3121 xvn[n].xv_size = sizeof *xvn; 3122 xvn[n].xv_vnode = vp; 3123 xvn[n].xv_id = 0; /* XXX compat */ 3124 #define XV_COPY(field) xvn[n].xv_##field = vp->v_##field 3125 XV_COPY(usecount); 3126 XV_COPY(writecount); 3127 XV_COPY(holdcnt); 3128 XV_COPY(mount); 3129 XV_COPY(numoutput); 3130 XV_COPY(type); 3131 #undef XV_COPY 3132 xvn[n].xv_flag = vp->v_vflag; 3133 3134 switch (vp->v_type) { 3135 case VREG: 3136 case VDIR: 3137 case VLNK: 3138 break; 3139 case VBLK: 3140 case VCHR: 3141 if (vp->v_rdev == NULL) { 3142 vrele(vp); 3143 continue; 3144 } 3145 xvn[n].xv_dev = dev2udev(vp->v_rdev); 3146 break; 3147 case VSOCK: 3148 xvn[n].xv_socket = vp->v_socket; 3149 break; 3150 case VFIFO: 3151 xvn[n].xv_fifo = vp->v_fifoinfo; 3152 break; 3153 case VNON: 3154 case VBAD: 3155 default: 3156 /* shouldn't happen? */ 3157 vrele(vp); 3158 continue; 3159 } 3160 vrele(vp); 3161 ++n; 3162 } 3163 MNT_IUNLOCK(mp); 3164 mtx_lock(&mountlist_mtx); 3165 vfs_unbusy(mp); 3166 if (n == len) 3167 break; 3168 } 3169 mtx_unlock(&mountlist_mtx); 3170 3171 error = SYSCTL_OUT(req, xvn, n * sizeof *xvn); 3172 free(xvn, M_TEMP); 3173 return (error); 3174 } 3175 3176 SYSCTL_PROC(_kern, KERN_VNODE, vnode, CTLTYPE_OPAQUE|CTLFLAG_RD, 3177 0, 0, sysctl_vnode, "S,xvnode", ""); 3178 #endif 3179 3180 /* 3181 * Unmount all filesystems. The list is traversed in reverse order 3182 * of mounting to avoid dependencies. 3183 */ 3184 void 3185 vfs_unmountall(void) 3186 { 3187 struct mount *mp; 3188 struct thread *td; 3189 int error; 3190 3191 KASSERT(curthread != NULL, ("vfs_unmountall: NULL curthread")); 3192 CTR1(KTR_VFS, "%s: unmounting all filesystems", __func__); 3193 td = curthread; 3194 3195 /* 3196 * Since this only runs when rebooting, it is not interlocked. 3197 */ 3198 while(!TAILQ_EMPTY(&mountlist)) { 3199 mp = TAILQ_LAST(&mountlist, mntlist); 3200 error = dounmount(mp, MNT_FORCE, td); 3201 if (error) { 3202 TAILQ_REMOVE(&mountlist, mp, mnt_list); 3203 /* 3204 * XXX: Due to the way in which we mount the root 3205 * file system off of devfs, devfs will generate a 3206 * "busy" warning when we try to unmount it before 3207 * the root. Don't print a warning as a result in 3208 * order to avoid false positive errors that may 3209 * cause needless upset. 3210 */ 3211 if (strcmp(mp->mnt_vfc->vfc_name, "devfs") != 0) { 3212 printf("unmount of %s failed (", 3213 mp->mnt_stat.f_mntonname); 3214 if (error == EBUSY) 3215 printf("BUSY)\n"); 3216 else 3217 printf("%d)\n", error); 3218 } 3219 } else { 3220 /* The unmount has removed mp from the mountlist */ 3221 } 3222 } 3223 } 3224 3225 /* 3226 * perform msync on all vnodes under a mount point 3227 * the mount point must be locked. 3228 */ 3229 void 3230 vfs_msync(struct mount *mp, int flags) 3231 { 3232 struct vnode *vp, *mvp; 3233 struct vm_object *obj; 3234 3235 CTR2(KTR_VFS, "%s: mp %p", __func__, mp); 3236 MNT_ILOCK(mp); 3237 MNT_VNODE_FOREACH(vp, mp, mvp) { 3238 VI_LOCK(vp); 3239 obj = vp->v_object; 3240 if (obj != NULL && (obj->flags & OBJ_MIGHTBEDIRTY) != 0 && 3241 (flags == MNT_WAIT || VOP_ISLOCKED(vp) == 0)) { 3242 MNT_IUNLOCK(mp); 3243 if (!vget(vp, 3244 LK_EXCLUSIVE | LK_RETRY | LK_INTERLOCK, 3245 curthread)) { 3246 if (vp->v_vflag & VV_NOSYNC) { /* unlinked */ 3247 vput(vp); 3248 MNT_ILOCK(mp); 3249 continue; 3250 } 3251 3252 obj = vp->v_object; 3253 if (obj != NULL) { 3254 VM_OBJECT_LOCK(obj); 3255 vm_object_page_clean(obj, 0, 0, 3256 flags == MNT_WAIT ? 3257 OBJPC_SYNC : OBJPC_NOSYNC); 3258 VM_OBJECT_UNLOCK(obj); 3259 } 3260 vput(vp); 3261 } 3262 MNT_ILOCK(mp); 3263 } else 3264 VI_UNLOCK(vp); 3265 } 3266 MNT_IUNLOCK(mp); 3267 } 3268 3269 /* 3270 * Mark a vnode as free, putting it up for recycling. 3271 */ 3272 static void 3273 vfree(struct vnode *vp) 3274 { 3275 3276 ASSERT_VI_LOCKED(vp, "vfree"); 3277 mtx_lock(&vnode_free_list_mtx); 3278 VNASSERT(vp->v_op != NULL, vp, ("vfree: vnode already reclaimed.")); 3279 VNASSERT((vp->v_iflag & VI_FREE) == 0, vp, ("vnode already free")); 3280 VNASSERT(VSHOULDFREE(vp), vp, ("vfree: freeing when we shouldn't")); 3281 VNASSERT((vp->v_iflag & VI_DOOMED) == 0, vp, 3282 ("vfree: Freeing doomed vnode")); 3283 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 3284 if (vp->v_iflag & VI_AGE) { 3285 TAILQ_INSERT_HEAD(&vnode_free_list, vp, v_freelist); 3286 } else { 3287 TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_freelist); 3288 } 3289 freevnodes++; 3290 vp->v_iflag &= ~VI_AGE; 3291 vp->v_iflag |= VI_FREE; 3292 mtx_unlock(&vnode_free_list_mtx); 3293 } 3294 3295 /* 3296 * Opposite of vfree() - mark a vnode as in use. 3297 */ 3298 static void 3299 vbusy(struct vnode *vp) 3300 { 3301 ASSERT_VI_LOCKED(vp, "vbusy"); 3302 VNASSERT((vp->v_iflag & VI_FREE) != 0, vp, ("vnode not free")); 3303 VNASSERT(vp->v_op != NULL, vp, ("vbusy: vnode already reclaimed.")); 3304 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 3305 3306 mtx_lock(&vnode_free_list_mtx); 3307 TAILQ_REMOVE(&vnode_free_list, vp, v_freelist); 3308 freevnodes--; 3309 vp->v_iflag &= ~(VI_FREE|VI_AGE); 3310 mtx_unlock(&vnode_free_list_mtx); 3311 } 3312 3313 static void 3314 destroy_vpollinfo(struct vpollinfo *vi) 3315 { 3316 knlist_destroy(&vi->vpi_selinfo.si_note); 3317 mtx_destroy(&vi->vpi_lock); 3318 uma_zfree(vnodepoll_zone, vi); 3319 } 3320 3321 /* 3322 * Initalize per-vnode helper structure to hold poll-related state. 3323 */ 3324 void 3325 v_addpollinfo(struct vnode *vp) 3326 { 3327 struct vpollinfo *vi; 3328 3329 if (vp->v_pollinfo != NULL) 3330 return; 3331 vi = uma_zalloc(vnodepoll_zone, M_WAITOK); 3332 mtx_init(&vi->vpi_lock, "vnode pollinfo", NULL, MTX_DEF); 3333 knlist_init(&vi->vpi_selinfo.si_note, vp, vfs_knllock, 3334 vfs_knlunlock, vfs_knl_assert_locked, vfs_knl_assert_unlocked); 3335 VI_LOCK(vp); 3336 if (vp->v_pollinfo != NULL) { 3337 VI_UNLOCK(vp); 3338 destroy_vpollinfo(vi); 3339 return; 3340 } 3341 vp->v_pollinfo = vi; 3342 VI_UNLOCK(vp); 3343 } 3344 3345 /* 3346 * Record a process's interest in events which might happen to 3347 * a vnode. Because poll uses the historic select-style interface 3348 * internally, this routine serves as both the ``check for any 3349 * pending events'' and the ``record my interest in future events'' 3350 * functions. (These are done together, while the lock is held, 3351 * to avoid race conditions.) 3352 */ 3353 int 3354 vn_pollrecord(struct vnode *vp, struct thread *td, int events) 3355 { 3356 3357 v_addpollinfo(vp); 3358 mtx_lock(&vp->v_pollinfo->vpi_lock); 3359 if (vp->v_pollinfo->vpi_revents & events) { 3360 /* 3361 * This leaves events we are not interested 3362 * in available for the other process which 3363 * which presumably had requested them 3364 * (otherwise they would never have been 3365 * recorded). 3366 */ 3367 events &= vp->v_pollinfo->vpi_revents; 3368 vp->v_pollinfo->vpi_revents &= ~events; 3369 3370 mtx_unlock(&vp->v_pollinfo->vpi_lock); 3371 return (events); 3372 } 3373 vp->v_pollinfo->vpi_events |= events; 3374 selrecord(td, &vp->v_pollinfo->vpi_selinfo); 3375 mtx_unlock(&vp->v_pollinfo->vpi_lock); 3376 return (0); 3377 } 3378 3379 /* 3380 * Routine to create and manage a filesystem syncer vnode. 3381 */ 3382 #define sync_close ((int (*)(struct vop_close_args *))nullop) 3383 static int sync_fsync(struct vop_fsync_args *); 3384 static int sync_inactive(struct vop_inactive_args *); 3385 static int sync_reclaim(struct vop_reclaim_args *); 3386 3387 static struct vop_vector sync_vnodeops = { 3388 .vop_bypass = VOP_EOPNOTSUPP, 3389 .vop_close = sync_close, /* close */ 3390 .vop_fsync = sync_fsync, /* fsync */ 3391 .vop_inactive = sync_inactive, /* inactive */ 3392 .vop_reclaim = sync_reclaim, /* reclaim */ 3393 .vop_lock1 = vop_stdlock, /* lock */ 3394 .vop_unlock = vop_stdunlock, /* unlock */ 3395 .vop_islocked = vop_stdislocked, /* islocked */ 3396 }; 3397 3398 /* 3399 * Create a new filesystem syncer vnode for the specified mount point. 3400 */ 3401 void 3402 vfs_allocate_syncvnode(struct mount *mp) 3403 { 3404 struct vnode *vp; 3405 struct bufobj *bo; 3406 static long start, incr, next; 3407 int error; 3408 3409 /* Allocate a new vnode */ 3410 error = getnewvnode("syncer", mp, &sync_vnodeops, &vp); 3411 if (error != 0) 3412 panic("vfs_allocate_syncvnode: getnewvnode() failed"); 3413 vp->v_type = VNON; 3414 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 3415 vp->v_vflag |= VV_FORCEINSMQ; 3416 error = insmntque(vp, mp); 3417 if (error != 0) 3418 panic("vfs_allocate_syncvnode: insmntque() failed"); 3419 vp->v_vflag &= ~VV_FORCEINSMQ; 3420 VOP_UNLOCK(vp, 0); 3421 /* 3422 * Place the vnode onto the syncer worklist. We attempt to 3423 * scatter them about on the list so that they will go off 3424 * at evenly distributed times even if all the filesystems 3425 * are mounted at once. 3426 */ 3427 next += incr; 3428 if (next == 0 || next > syncer_maxdelay) { 3429 start /= 2; 3430 incr /= 2; 3431 if (start == 0) { 3432 start = syncer_maxdelay / 2; 3433 incr = syncer_maxdelay; 3434 } 3435 next = start; 3436 } 3437 bo = &vp->v_bufobj; 3438 BO_LOCK(bo); 3439 vn_syncer_add_to_worklist(bo, syncdelay > 0 ? next % syncdelay : 0); 3440 /* XXX - vn_syncer_add_to_worklist() also grabs and drops sync_mtx. */ 3441 mtx_lock(&sync_mtx); 3442 sync_vnode_count++; 3443 if (mp->mnt_syncer == NULL) { 3444 mp->mnt_syncer = vp; 3445 vp = NULL; 3446 } 3447 mtx_unlock(&sync_mtx); 3448 BO_UNLOCK(bo); 3449 if (vp != NULL) { 3450 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 3451 vgone(vp); 3452 vput(vp); 3453 } 3454 } 3455 3456 void 3457 vfs_deallocate_syncvnode(struct mount *mp) 3458 { 3459 struct vnode *vp; 3460 3461 mtx_lock(&sync_mtx); 3462 vp = mp->mnt_syncer; 3463 if (vp != NULL) 3464 mp->mnt_syncer = NULL; 3465 mtx_unlock(&sync_mtx); 3466 if (vp != NULL) 3467 vrele(vp); 3468 } 3469 3470 /* 3471 * Do a lazy sync of the filesystem. 3472 */ 3473 static int 3474 sync_fsync(struct vop_fsync_args *ap) 3475 { 3476 struct vnode *syncvp = ap->a_vp; 3477 struct mount *mp = syncvp->v_mount; 3478 int error; 3479 struct bufobj *bo; 3480 3481 /* 3482 * We only need to do something if this is a lazy evaluation. 3483 */ 3484 if (ap->a_waitfor != MNT_LAZY) 3485 return (0); 3486 3487 /* 3488 * Move ourselves to the back of the sync list. 3489 */ 3490 bo = &syncvp->v_bufobj; 3491 BO_LOCK(bo); 3492 vn_syncer_add_to_worklist(bo, syncdelay); 3493 BO_UNLOCK(bo); 3494 3495 /* 3496 * Walk the list of vnodes pushing all that are dirty and 3497 * not already on the sync list. 3498 */ 3499 mtx_lock(&mountlist_mtx); 3500 if (vfs_busy(mp, MBF_NOWAIT | MBF_MNTLSTLOCK) != 0) { 3501 mtx_unlock(&mountlist_mtx); 3502 return (0); 3503 } 3504 if (vn_start_write(NULL, &mp, V_NOWAIT) != 0) { 3505 vfs_unbusy(mp); 3506 return (0); 3507 } 3508 MNT_ILOCK(mp); 3509 mp->mnt_noasync++; 3510 mp->mnt_kern_flag &= ~MNTK_ASYNC; 3511 MNT_IUNLOCK(mp); 3512 vfs_msync(mp, MNT_NOWAIT); 3513 error = VFS_SYNC(mp, MNT_LAZY); 3514 MNT_ILOCK(mp); 3515 mp->mnt_noasync--; 3516 if ((mp->mnt_flag & MNT_ASYNC) != 0 && mp->mnt_noasync == 0) 3517 mp->mnt_kern_flag |= MNTK_ASYNC; 3518 MNT_IUNLOCK(mp); 3519 vn_finished_write(mp); 3520 vfs_unbusy(mp); 3521 return (error); 3522 } 3523 3524 /* 3525 * The syncer vnode is no referenced. 3526 */ 3527 static int 3528 sync_inactive(struct vop_inactive_args *ap) 3529 { 3530 3531 vgone(ap->a_vp); 3532 return (0); 3533 } 3534 3535 /* 3536 * The syncer vnode is no longer needed and is being decommissioned. 3537 * 3538 * Modifications to the worklist must be protected by sync_mtx. 3539 */ 3540 static int 3541 sync_reclaim(struct vop_reclaim_args *ap) 3542 { 3543 struct vnode *vp = ap->a_vp; 3544 struct bufobj *bo; 3545 3546 bo = &vp->v_bufobj; 3547 BO_LOCK(bo); 3548 mtx_lock(&sync_mtx); 3549 if (vp->v_mount->mnt_syncer == vp) 3550 vp->v_mount->mnt_syncer = NULL; 3551 if (bo->bo_flag & BO_ONWORKLST) { 3552 LIST_REMOVE(bo, bo_synclist); 3553 syncer_worklist_len--; 3554 sync_vnode_count--; 3555 bo->bo_flag &= ~BO_ONWORKLST; 3556 } 3557 mtx_unlock(&sync_mtx); 3558 BO_UNLOCK(bo); 3559 3560 return (0); 3561 } 3562 3563 /* 3564 * Check if vnode represents a disk device 3565 */ 3566 int 3567 vn_isdisk(struct vnode *vp, int *errp) 3568 { 3569 int error; 3570 3571 error = 0; 3572 dev_lock(); 3573 if (vp->v_type != VCHR) 3574 error = ENOTBLK; 3575 else if (vp->v_rdev == NULL) 3576 error = ENXIO; 3577 else if (vp->v_rdev->si_devsw == NULL) 3578 error = ENXIO; 3579 else if (!(vp->v_rdev->si_devsw->d_flags & D_DISK)) 3580 error = ENOTBLK; 3581 dev_unlock(); 3582 if (errp != NULL) 3583 *errp = error; 3584 return (error == 0); 3585 } 3586 3587 /* 3588 * Common filesystem object access control check routine. Accepts a 3589 * vnode's type, "mode", uid and gid, requested access mode, credentials, 3590 * and optional call-by-reference privused argument allowing vaccess() 3591 * to indicate to the caller whether privilege was used to satisfy the 3592 * request (obsoleted). Returns 0 on success, or an errno on failure. 3593 * 3594 * The ifdef'd CAPABILITIES version is here for reference, but is not 3595 * actually used. 3596 */ 3597 int 3598 vaccess(enum vtype type, mode_t file_mode, uid_t file_uid, gid_t file_gid, 3599 accmode_t accmode, struct ucred *cred, int *privused) 3600 { 3601 accmode_t dac_granted; 3602 accmode_t priv_granted; 3603 3604 KASSERT((accmode & ~(VEXEC | VWRITE | VREAD | VADMIN | VAPPEND)) == 0, 3605 ("invalid bit in accmode")); 3606 KASSERT((accmode & VAPPEND) == 0 || (accmode & VWRITE), 3607 ("VAPPEND without VWRITE")); 3608 3609 /* 3610 * Look for a normal, non-privileged way to access the file/directory 3611 * as requested. If it exists, go with that. 3612 */ 3613 3614 if (privused != NULL) 3615 *privused = 0; 3616 3617 dac_granted = 0; 3618 3619 /* Check the owner. */ 3620 if (cred->cr_uid == file_uid) { 3621 dac_granted |= VADMIN; 3622 if (file_mode & S_IXUSR) 3623 dac_granted |= VEXEC; 3624 if (file_mode & S_IRUSR) 3625 dac_granted |= VREAD; 3626 if (file_mode & S_IWUSR) 3627 dac_granted |= (VWRITE | VAPPEND); 3628 3629 if ((accmode & dac_granted) == accmode) 3630 return (0); 3631 3632 goto privcheck; 3633 } 3634 3635 /* Otherwise, check the groups (first match) */ 3636 if (groupmember(file_gid, cred)) { 3637 if (file_mode & S_IXGRP) 3638 dac_granted |= VEXEC; 3639 if (file_mode & S_IRGRP) 3640 dac_granted |= VREAD; 3641 if (file_mode & S_IWGRP) 3642 dac_granted |= (VWRITE | VAPPEND); 3643 3644 if ((accmode & dac_granted) == accmode) 3645 return (0); 3646 3647 goto privcheck; 3648 } 3649 3650 /* Otherwise, check everyone else. */ 3651 if (file_mode & S_IXOTH) 3652 dac_granted |= VEXEC; 3653 if (file_mode & S_IROTH) 3654 dac_granted |= VREAD; 3655 if (file_mode & S_IWOTH) 3656 dac_granted |= (VWRITE | VAPPEND); 3657 if ((accmode & dac_granted) == accmode) 3658 return (0); 3659 3660 privcheck: 3661 /* 3662 * Build a privilege mask to determine if the set of privileges 3663 * satisfies the requirements when combined with the granted mask 3664 * from above. For each privilege, if the privilege is required, 3665 * bitwise or the request type onto the priv_granted mask. 3666 */ 3667 priv_granted = 0; 3668 3669 if (type == VDIR) { 3670 /* 3671 * For directories, use PRIV_VFS_LOOKUP to satisfy VEXEC 3672 * requests, instead of PRIV_VFS_EXEC. 3673 */ 3674 if ((accmode & VEXEC) && ((dac_granted & VEXEC) == 0) && 3675 !priv_check_cred(cred, PRIV_VFS_LOOKUP, 0)) 3676 priv_granted |= VEXEC; 3677 } else { 3678 /* 3679 * Ensure that at least one execute bit is on. Otherwise, 3680 * a privileged user will always succeed, and we don't want 3681 * this to happen unless the file really is executable. 3682 */ 3683 if ((accmode & VEXEC) && ((dac_granted & VEXEC) == 0) && 3684 (file_mode & (S_IXUSR | S_IXGRP | S_IXOTH)) != 0 && 3685 !priv_check_cred(cred, PRIV_VFS_EXEC, 0)) 3686 priv_granted |= VEXEC; 3687 } 3688 3689 if ((accmode & VREAD) && ((dac_granted & VREAD) == 0) && 3690 !priv_check_cred(cred, PRIV_VFS_READ, 0)) 3691 priv_granted |= VREAD; 3692 3693 if ((accmode & VWRITE) && ((dac_granted & VWRITE) == 0) && 3694 !priv_check_cred(cred, PRIV_VFS_WRITE, 0)) 3695 priv_granted |= (VWRITE | VAPPEND); 3696 3697 if ((accmode & VADMIN) && ((dac_granted & VADMIN) == 0) && 3698 !priv_check_cred(cred, PRIV_VFS_ADMIN, 0)) 3699 priv_granted |= VADMIN; 3700 3701 if ((accmode & (priv_granted | dac_granted)) == accmode) { 3702 /* XXX audit: privilege used */ 3703 if (privused != NULL) 3704 *privused = 1; 3705 return (0); 3706 } 3707 3708 return ((accmode & VADMIN) ? EPERM : EACCES); 3709 } 3710 3711 /* 3712 * Credential check based on process requesting service, and per-attribute 3713 * permissions. 3714 */ 3715 int 3716 extattr_check_cred(struct vnode *vp, int attrnamespace, struct ucred *cred, 3717 struct thread *td, accmode_t accmode) 3718 { 3719 3720 /* 3721 * Kernel-invoked always succeeds. 3722 */ 3723 if (cred == NOCRED) 3724 return (0); 3725 3726 /* 3727 * Do not allow privileged processes in jail to directly manipulate 3728 * system attributes. 3729 */ 3730 switch (attrnamespace) { 3731 case EXTATTR_NAMESPACE_SYSTEM: 3732 /* Potentially should be: return (EPERM); */ 3733 return (priv_check_cred(cred, PRIV_VFS_EXTATTR_SYSTEM, 0)); 3734 case EXTATTR_NAMESPACE_USER: 3735 return (VOP_ACCESS(vp, accmode, cred, td)); 3736 default: 3737 return (EPERM); 3738 } 3739 } 3740 3741 #ifdef DEBUG_VFS_LOCKS 3742 /* 3743 * This only exists to supress warnings from unlocked specfs accesses. It is 3744 * no longer ok to have an unlocked VFS. 3745 */ 3746 #define IGNORE_LOCK(vp) (panicstr != NULL || (vp) == NULL || \ 3747 (vp)->v_type == VCHR || (vp)->v_type == VBAD) 3748 3749 int vfs_badlock_ddb = 1; /* Drop into debugger on violation. */ 3750 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_ddb, CTLFLAG_RW, &vfs_badlock_ddb, 0, 3751 "Drop into debugger on lock violation"); 3752 3753 int vfs_badlock_mutex = 1; /* Check for interlock across VOPs. */ 3754 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_mutex, CTLFLAG_RW, &vfs_badlock_mutex, 3755 0, "Check for interlock across VOPs"); 3756 3757 int vfs_badlock_print = 1; /* Print lock violations. */ 3758 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_print, CTLFLAG_RW, &vfs_badlock_print, 3759 0, "Print lock violations"); 3760 3761 #ifdef KDB 3762 int vfs_badlock_backtrace = 1; /* Print backtrace at lock violations. */ 3763 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_backtrace, CTLFLAG_RW, 3764 &vfs_badlock_backtrace, 0, "Print backtrace at lock violations"); 3765 #endif 3766 3767 static void 3768 vfs_badlock(const char *msg, const char *str, struct vnode *vp) 3769 { 3770 3771 #ifdef KDB 3772 if (vfs_badlock_backtrace) 3773 kdb_backtrace(); 3774 #endif 3775 if (vfs_badlock_print) 3776 printf("%s: %p %s\n", str, (void *)vp, msg); 3777 if (vfs_badlock_ddb) 3778 kdb_enter(KDB_WHY_VFSLOCK, "lock violation"); 3779 } 3780 3781 void 3782 assert_vi_locked(struct vnode *vp, const char *str) 3783 { 3784 3785 if (vfs_badlock_mutex && !mtx_owned(VI_MTX(vp))) 3786 vfs_badlock("interlock is not locked but should be", str, vp); 3787 } 3788 3789 void 3790 assert_vi_unlocked(struct vnode *vp, const char *str) 3791 { 3792 3793 if (vfs_badlock_mutex && mtx_owned(VI_MTX(vp))) 3794 vfs_badlock("interlock is locked but should not be", str, vp); 3795 } 3796 3797 void 3798 assert_vop_locked(struct vnode *vp, const char *str) 3799 { 3800 3801 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) == 0) 3802 vfs_badlock("is not locked but should be", str, vp); 3803 } 3804 3805 void 3806 assert_vop_unlocked(struct vnode *vp, const char *str) 3807 { 3808 3809 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) == LK_EXCLUSIVE) 3810 vfs_badlock("is locked but should not be", str, vp); 3811 } 3812 3813 void 3814 assert_vop_elocked(struct vnode *vp, const char *str) 3815 { 3816 3817 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) != LK_EXCLUSIVE) 3818 vfs_badlock("is not exclusive locked but should be", str, vp); 3819 } 3820 3821 #if 0 3822 void 3823 assert_vop_elocked_other(struct vnode *vp, const char *str) 3824 { 3825 3826 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) != LK_EXCLOTHER) 3827 vfs_badlock("is not exclusive locked by another thread", 3828 str, vp); 3829 } 3830 3831 void 3832 assert_vop_slocked(struct vnode *vp, const char *str) 3833 { 3834 3835 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) != LK_SHARED) 3836 vfs_badlock("is not locked shared but should be", str, vp); 3837 } 3838 #endif /* 0 */ 3839 #endif /* DEBUG_VFS_LOCKS */ 3840 3841 void 3842 vop_rename_fail(struct vop_rename_args *ap) 3843 { 3844 3845 if (ap->a_tvp != NULL) 3846 vput(ap->a_tvp); 3847 if (ap->a_tdvp == ap->a_tvp) 3848 vrele(ap->a_tdvp); 3849 else 3850 vput(ap->a_tdvp); 3851 vrele(ap->a_fdvp); 3852 vrele(ap->a_fvp); 3853 } 3854 3855 void 3856 vop_rename_pre(void *ap) 3857 { 3858 struct vop_rename_args *a = ap; 3859 3860 #ifdef DEBUG_VFS_LOCKS 3861 if (a->a_tvp) 3862 ASSERT_VI_UNLOCKED(a->a_tvp, "VOP_RENAME"); 3863 ASSERT_VI_UNLOCKED(a->a_tdvp, "VOP_RENAME"); 3864 ASSERT_VI_UNLOCKED(a->a_fvp, "VOP_RENAME"); 3865 ASSERT_VI_UNLOCKED(a->a_fdvp, "VOP_RENAME"); 3866 3867 /* Check the source (from). */ 3868 if (a->a_tdvp->v_vnlock != a->a_fdvp->v_vnlock && 3869 (a->a_tvp == NULL || a->a_tvp->v_vnlock != a->a_fdvp->v_vnlock)) 3870 ASSERT_VOP_UNLOCKED(a->a_fdvp, "vop_rename: fdvp locked"); 3871 if (a->a_tvp == NULL || a->a_tvp->v_vnlock != a->a_fvp->v_vnlock) 3872 ASSERT_VOP_UNLOCKED(a->a_fvp, "vop_rename: fvp locked"); 3873 3874 /* Check the target. */ 3875 if (a->a_tvp) 3876 ASSERT_VOP_LOCKED(a->a_tvp, "vop_rename: tvp not locked"); 3877 ASSERT_VOP_LOCKED(a->a_tdvp, "vop_rename: tdvp not locked"); 3878 #endif 3879 if (a->a_tdvp != a->a_fdvp) 3880 vhold(a->a_fdvp); 3881 if (a->a_tvp != a->a_fvp) 3882 vhold(a->a_fvp); 3883 vhold(a->a_tdvp); 3884 if (a->a_tvp) 3885 vhold(a->a_tvp); 3886 } 3887 3888 void 3889 vop_strategy_pre(void *ap) 3890 { 3891 #ifdef DEBUG_VFS_LOCKS 3892 struct vop_strategy_args *a; 3893 struct buf *bp; 3894 3895 a = ap; 3896 bp = a->a_bp; 3897 3898 /* 3899 * Cluster ops lock their component buffers but not the IO container. 3900 */ 3901 if ((bp->b_flags & B_CLUSTER) != 0) 3902 return; 3903 3904 if (panicstr == NULL && !BUF_ISLOCKED(bp)) { 3905 if (vfs_badlock_print) 3906 printf( 3907 "VOP_STRATEGY: bp is not locked but should be\n"); 3908 if (vfs_badlock_ddb) 3909 kdb_enter(KDB_WHY_VFSLOCK, "lock violation"); 3910 } 3911 #endif 3912 } 3913 3914 void 3915 vop_lookup_pre(void *ap) 3916 { 3917 #ifdef DEBUG_VFS_LOCKS 3918 struct vop_lookup_args *a; 3919 struct vnode *dvp; 3920 3921 a = ap; 3922 dvp = a->a_dvp; 3923 ASSERT_VI_UNLOCKED(dvp, "VOP_LOOKUP"); 3924 ASSERT_VOP_LOCKED(dvp, "VOP_LOOKUP"); 3925 #endif 3926 } 3927 3928 void 3929 vop_lookup_post(void *ap, int rc) 3930 { 3931 #ifdef DEBUG_VFS_LOCKS 3932 struct vop_lookup_args *a; 3933 struct vnode *dvp; 3934 struct vnode *vp; 3935 3936 a = ap; 3937 dvp = a->a_dvp; 3938 vp = *(a->a_vpp); 3939 3940 ASSERT_VI_UNLOCKED(dvp, "VOP_LOOKUP"); 3941 ASSERT_VOP_LOCKED(dvp, "VOP_LOOKUP"); 3942 3943 if (!rc) 3944 ASSERT_VOP_LOCKED(vp, "VOP_LOOKUP (child)"); 3945 #endif 3946 } 3947 3948 void 3949 vop_lock_pre(void *ap) 3950 { 3951 #ifdef DEBUG_VFS_LOCKS 3952 struct vop_lock1_args *a = ap; 3953 3954 if ((a->a_flags & LK_INTERLOCK) == 0) 3955 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_LOCK"); 3956 else 3957 ASSERT_VI_LOCKED(a->a_vp, "VOP_LOCK"); 3958 #endif 3959 } 3960 3961 void 3962 vop_lock_post(void *ap, int rc) 3963 { 3964 #ifdef DEBUG_VFS_LOCKS 3965 struct vop_lock1_args *a = ap; 3966 3967 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_LOCK"); 3968 if (rc == 0) 3969 ASSERT_VOP_LOCKED(a->a_vp, "VOP_LOCK"); 3970 #endif 3971 } 3972 3973 void 3974 vop_unlock_pre(void *ap) 3975 { 3976 #ifdef DEBUG_VFS_LOCKS 3977 struct vop_unlock_args *a = ap; 3978 3979 if (a->a_flags & LK_INTERLOCK) 3980 ASSERT_VI_LOCKED(a->a_vp, "VOP_UNLOCK"); 3981 ASSERT_VOP_LOCKED(a->a_vp, "VOP_UNLOCK"); 3982 #endif 3983 } 3984 3985 void 3986 vop_unlock_post(void *ap, int rc) 3987 { 3988 #ifdef DEBUG_VFS_LOCKS 3989 struct vop_unlock_args *a = ap; 3990 3991 if (a->a_flags & LK_INTERLOCK) 3992 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_UNLOCK"); 3993 #endif 3994 } 3995 3996 void 3997 vop_create_post(void *ap, int rc) 3998 { 3999 struct vop_create_args *a = ap; 4000 4001 if (!rc) 4002 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 4003 } 4004 4005 void 4006 vop_link_post(void *ap, int rc) 4007 { 4008 struct vop_link_args *a = ap; 4009 4010 if (!rc) { 4011 VFS_KNOTE_LOCKED(a->a_vp, NOTE_LINK); 4012 VFS_KNOTE_LOCKED(a->a_tdvp, NOTE_WRITE); 4013 } 4014 } 4015 4016 void 4017 vop_mkdir_post(void *ap, int rc) 4018 { 4019 struct vop_mkdir_args *a = ap; 4020 4021 if (!rc) 4022 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE | NOTE_LINK); 4023 } 4024 4025 void 4026 vop_mknod_post(void *ap, int rc) 4027 { 4028 struct vop_mknod_args *a = ap; 4029 4030 if (!rc) 4031 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 4032 } 4033 4034 void 4035 vop_remove_post(void *ap, int rc) 4036 { 4037 struct vop_remove_args *a = ap; 4038 4039 if (!rc) { 4040 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 4041 VFS_KNOTE_LOCKED(a->a_vp, NOTE_DELETE); 4042 } 4043 } 4044 4045 void 4046 vop_rename_post(void *ap, int rc) 4047 { 4048 struct vop_rename_args *a = ap; 4049 4050 if (!rc) { 4051 VFS_KNOTE_UNLOCKED(a->a_fdvp, NOTE_WRITE); 4052 VFS_KNOTE_UNLOCKED(a->a_tdvp, NOTE_WRITE); 4053 VFS_KNOTE_UNLOCKED(a->a_fvp, NOTE_RENAME); 4054 if (a->a_tvp) 4055 VFS_KNOTE_UNLOCKED(a->a_tvp, NOTE_DELETE); 4056 } 4057 if (a->a_tdvp != a->a_fdvp) 4058 vdrop(a->a_fdvp); 4059 if (a->a_tvp != a->a_fvp) 4060 vdrop(a->a_fvp); 4061 vdrop(a->a_tdvp); 4062 if (a->a_tvp) 4063 vdrop(a->a_tvp); 4064 } 4065 4066 void 4067 vop_rmdir_post(void *ap, int rc) 4068 { 4069 struct vop_rmdir_args *a = ap; 4070 4071 if (!rc) { 4072 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE | NOTE_LINK); 4073 VFS_KNOTE_LOCKED(a->a_vp, NOTE_DELETE); 4074 } 4075 } 4076 4077 void 4078 vop_setattr_post(void *ap, int rc) 4079 { 4080 struct vop_setattr_args *a = ap; 4081 4082 if (!rc) 4083 VFS_KNOTE_LOCKED(a->a_vp, NOTE_ATTRIB); 4084 } 4085 4086 void 4087 vop_symlink_post(void *ap, int rc) 4088 { 4089 struct vop_symlink_args *a = ap; 4090 4091 if (!rc) 4092 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 4093 } 4094 4095 static struct knlist fs_knlist; 4096 4097 static void 4098 vfs_event_init(void *arg) 4099 { 4100 knlist_init_mtx(&fs_knlist, NULL); 4101 } 4102 /* XXX - correct order? */ 4103 SYSINIT(vfs_knlist, SI_SUB_VFS, SI_ORDER_ANY, vfs_event_init, NULL); 4104 4105 void 4106 vfs_event_signal(fsid_t *fsid, uint32_t event, intptr_t data __unused) 4107 { 4108 4109 KNOTE_UNLOCKED(&fs_knlist, event); 4110 } 4111 4112 static int filt_fsattach(struct knote *kn); 4113 static void filt_fsdetach(struct knote *kn); 4114 static int filt_fsevent(struct knote *kn, long hint); 4115 4116 struct filterops fs_filtops = { 4117 .f_isfd = 0, 4118 .f_attach = filt_fsattach, 4119 .f_detach = filt_fsdetach, 4120 .f_event = filt_fsevent 4121 }; 4122 4123 static int 4124 filt_fsattach(struct knote *kn) 4125 { 4126 4127 kn->kn_flags |= EV_CLEAR; 4128 knlist_add(&fs_knlist, kn, 0); 4129 return (0); 4130 } 4131 4132 static void 4133 filt_fsdetach(struct knote *kn) 4134 { 4135 4136 knlist_remove(&fs_knlist, kn, 0); 4137 } 4138 4139 static int 4140 filt_fsevent(struct knote *kn, long hint) 4141 { 4142 4143 kn->kn_fflags |= hint; 4144 return (kn->kn_fflags != 0); 4145 } 4146 4147 static int 4148 sysctl_vfs_ctl(SYSCTL_HANDLER_ARGS) 4149 { 4150 struct vfsidctl vc; 4151 int error; 4152 struct mount *mp; 4153 4154 error = SYSCTL_IN(req, &vc, sizeof(vc)); 4155 if (error) 4156 return (error); 4157 if (vc.vc_vers != VFS_CTL_VERS1) 4158 return (EINVAL); 4159 mp = vfs_getvfs(&vc.vc_fsid); 4160 if (mp == NULL) 4161 return (ENOENT); 4162 /* ensure that a specific sysctl goes to the right filesystem. */ 4163 if (strcmp(vc.vc_fstypename, "*") != 0 && 4164 strcmp(vc.vc_fstypename, mp->mnt_vfc->vfc_name) != 0) { 4165 vfs_rel(mp); 4166 return (EINVAL); 4167 } 4168 VCTLTOREQ(&vc, req); 4169 error = VFS_SYSCTL(mp, vc.vc_op, req); 4170 vfs_rel(mp); 4171 return (error); 4172 } 4173 4174 SYSCTL_PROC(_vfs, OID_AUTO, ctl, CTLTYPE_OPAQUE | CTLFLAG_WR, 4175 NULL, 0, sysctl_vfs_ctl, "", 4176 "Sysctl by fsid"); 4177 4178 /* 4179 * Function to initialize a va_filerev field sensibly. 4180 * XXX: Wouldn't a random number make a lot more sense ?? 4181 */ 4182 u_quad_t 4183 init_va_filerev(void) 4184 { 4185 struct bintime bt; 4186 4187 getbinuptime(&bt); 4188 return (((u_quad_t)bt.sec << 32LL) | (bt.frac >> 32LL)); 4189 } 4190 4191 static int filt_vfsread(struct knote *kn, long hint); 4192 static int filt_vfswrite(struct knote *kn, long hint); 4193 static int filt_vfsvnode(struct knote *kn, long hint); 4194 static void filt_vfsdetach(struct knote *kn); 4195 static struct filterops vfsread_filtops = { 4196 .f_isfd = 1, 4197 .f_detach = filt_vfsdetach, 4198 .f_event = filt_vfsread 4199 }; 4200 static struct filterops vfswrite_filtops = { 4201 .f_isfd = 1, 4202 .f_detach = filt_vfsdetach, 4203 .f_event = filt_vfswrite 4204 }; 4205 static struct filterops vfsvnode_filtops = { 4206 .f_isfd = 1, 4207 .f_detach = filt_vfsdetach, 4208 .f_event = filt_vfsvnode 4209 }; 4210 4211 static void 4212 vfs_knllock(void *arg) 4213 { 4214 struct vnode *vp = arg; 4215 4216 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 4217 } 4218 4219 static void 4220 vfs_knlunlock(void *arg) 4221 { 4222 struct vnode *vp = arg; 4223 4224 VOP_UNLOCK(vp, 0); 4225 } 4226 4227 static void 4228 vfs_knl_assert_locked(void *arg) 4229 { 4230 #ifdef DEBUG_VFS_LOCKS 4231 struct vnode *vp = arg; 4232 4233 ASSERT_VOP_LOCKED(vp, "vfs_knl_assert_locked"); 4234 #endif 4235 } 4236 4237 static void 4238 vfs_knl_assert_unlocked(void *arg) 4239 { 4240 #ifdef DEBUG_VFS_LOCKS 4241 struct vnode *vp = arg; 4242 4243 ASSERT_VOP_UNLOCKED(vp, "vfs_knl_assert_unlocked"); 4244 #endif 4245 } 4246 4247 int 4248 vfs_kqfilter(struct vop_kqfilter_args *ap) 4249 { 4250 struct vnode *vp = ap->a_vp; 4251 struct knote *kn = ap->a_kn; 4252 struct knlist *knl; 4253 4254 switch (kn->kn_filter) { 4255 case EVFILT_READ: 4256 kn->kn_fop = &vfsread_filtops; 4257 break; 4258 case EVFILT_WRITE: 4259 kn->kn_fop = &vfswrite_filtops; 4260 break; 4261 case EVFILT_VNODE: 4262 kn->kn_fop = &vfsvnode_filtops; 4263 break; 4264 default: 4265 return (EINVAL); 4266 } 4267 4268 kn->kn_hook = (caddr_t)vp; 4269 4270 v_addpollinfo(vp); 4271 if (vp->v_pollinfo == NULL) 4272 return (ENOMEM); 4273 knl = &vp->v_pollinfo->vpi_selinfo.si_note; 4274 knlist_add(knl, kn, 0); 4275 4276 return (0); 4277 } 4278 4279 /* 4280 * Detach knote from vnode 4281 */ 4282 static void 4283 filt_vfsdetach(struct knote *kn) 4284 { 4285 struct vnode *vp = (struct vnode *)kn->kn_hook; 4286 4287 KASSERT(vp->v_pollinfo != NULL, ("Missing v_pollinfo")); 4288 knlist_remove(&vp->v_pollinfo->vpi_selinfo.si_note, kn, 0); 4289 } 4290 4291 /*ARGSUSED*/ 4292 static int 4293 filt_vfsread(struct knote *kn, long hint) 4294 { 4295 struct vnode *vp = (struct vnode *)kn->kn_hook; 4296 struct vattr va; 4297 int res; 4298 4299 /* 4300 * filesystem is gone, so set the EOF flag and schedule 4301 * the knote for deletion. 4302 */ 4303 if (hint == NOTE_REVOKE) { 4304 VI_LOCK(vp); 4305 kn->kn_flags |= (EV_EOF | EV_ONESHOT); 4306 VI_UNLOCK(vp); 4307 return (1); 4308 } 4309 4310 if (VOP_GETATTR(vp, &va, curthread->td_ucred)) 4311 return (0); 4312 4313 VI_LOCK(vp); 4314 kn->kn_data = va.va_size - kn->kn_fp->f_offset; 4315 res = (kn->kn_data != 0); 4316 VI_UNLOCK(vp); 4317 return (res); 4318 } 4319 4320 /*ARGSUSED*/ 4321 static int 4322 filt_vfswrite(struct knote *kn, long hint) 4323 { 4324 struct vnode *vp = (struct vnode *)kn->kn_hook; 4325 4326 VI_LOCK(vp); 4327 4328 /* 4329 * filesystem is gone, so set the EOF flag and schedule 4330 * the knote for deletion. 4331 */ 4332 if (hint == NOTE_REVOKE) 4333 kn->kn_flags |= (EV_EOF | EV_ONESHOT); 4334 4335 kn->kn_data = 0; 4336 VI_UNLOCK(vp); 4337 return (1); 4338 } 4339 4340 static int 4341 filt_vfsvnode(struct knote *kn, long hint) 4342 { 4343 struct vnode *vp = (struct vnode *)kn->kn_hook; 4344 int res; 4345 4346 VI_LOCK(vp); 4347 if (kn->kn_sfflags & hint) 4348 kn->kn_fflags |= hint; 4349 if (hint == NOTE_REVOKE) { 4350 kn->kn_flags |= EV_EOF; 4351 VI_UNLOCK(vp); 4352 return (1); 4353 } 4354 res = (kn->kn_fflags != 0); 4355 VI_UNLOCK(vp); 4356 return (res); 4357 } 4358 4359 int 4360 vfs_read_dirent(struct vop_readdir_args *ap, struct dirent *dp, off_t off) 4361 { 4362 int error; 4363 4364 if (dp->d_reclen > ap->a_uio->uio_resid) 4365 return (ENAMETOOLONG); 4366 error = uiomove(dp, dp->d_reclen, ap->a_uio); 4367 if (error) { 4368 if (ap->a_ncookies != NULL) { 4369 if (ap->a_cookies != NULL) 4370 free(ap->a_cookies, M_TEMP); 4371 ap->a_cookies = NULL; 4372 *ap->a_ncookies = 0; 4373 } 4374 return (error); 4375 } 4376 if (ap->a_ncookies == NULL) 4377 return (0); 4378 4379 KASSERT(ap->a_cookies, 4380 ("NULL ap->a_cookies value with non-NULL ap->a_ncookies!")); 4381 4382 *ap->a_cookies = realloc(*ap->a_cookies, 4383 (*ap->a_ncookies + 1) * sizeof(u_long), M_TEMP, M_WAITOK | M_ZERO); 4384 (*ap->a_cookies)[*ap->a_ncookies] = off; 4385 return (0); 4386 } 4387 4388 /* 4389 * Mark for update the access time of the file if the filesystem 4390 * supports VOP_MARKATIME. This functionality is used by execve and 4391 * mmap, so we want to avoid the I/O implied by directly setting 4392 * va_atime for the sake of efficiency. 4393 */ 4394 void 4395 vfs_mark_atime(struct vnode *vp, struct ucred *cred) 4396 { 4397 struct mount *mp; 4398 4399 mp = vp->v_mount; 4400 VFS_ASSERT_GIANT(mp); 4401 ASSERT_VOP_LOCKED(vp, "vfs_mark_atime"); 4402 if (mp != NULL && (mp->mnt_flag & (MNT_NOATIME | MNT_RDONLY)) == 0) 4403 (void)VOP_MARKATIME(vp); 4404 } 4405 4406 /* 4407 * The purpose of this routine is to remove granularity from accmode_t, 4408 * reducing it into standard unix access bits - VEXEC, VREAD, VWRITE, 4409 * VADMIN and VAPPEND. 4410 * 4411 * If it returns 0, the caller is supposed to continue with the usual 4412 * access checks using 'accmode' as modified by this routine. If it 4413 * returns nonzero value, the caller is supposed to return that value 4414 * as errno. 4415 * 4416 * Note that after this routine runs, accmode may be zero. 4417 */ 4418 int 4419 vfs_unixify_accmode(accmode_t *accmode) 4420 { 4421 /* 4422 * There is no way to specify explicit "deny" rule using 4423 * file mode or POSIX.1e ACLs. 4424 */ 4425 if (*accmode & VEXPLICIT_DENY) { 4426 *accmode = 0; 4427 return (0); 4428 } 4429 4430 /* 4431 * None of these can be translated into usual access bits. 4432 * Also, the common case for NFSv4 ACLs is to not contain 4433 * either of these bits. Caller should check for VWRITE 4434 * on the containing directory instead. 4435 */ 4436 if (*accmode & (VDELETE_CHILD | VDELETE)) 4437 return (EPERM); 4438 4439 if (*accmode & VADMIN_PERMS) { 4440 *accmode &= ~VADMIN_PERMS; 4441 *accmode |= VADMIN; 4442 } 4443 4444 /* 4445 * There is no way to deny VREAD_ATTRIBUTES, VREAD_ACL 4446 * or VSYNCHRONIZE using file mode or POSIX.1e ACL. 4447 */ 4448 *accmode &= ~(VSTAT_PERMS | VSYNCHRONIZE); 4449 4450 return (0); 4451 } 4452