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 46 #include <sys/param.h> 47 #include <sys/systm.h> 48 #include <sys/bio.h> 49 #include <sys/buf.h> 50 #include <sys/condvar.h> 51 #include <sys/conf.h> 52 #include <sys/dirent.h> 53 #include <sys/event.h> 54 #include <sys/eventhandler.h> 55 #include <sys/extattr.h> 56 #include <sys/file.h> 57 #include <sys/fcntl.h> 58 #include <sys/jail.h> 59 #include <sys/kdb.h> 60 #include <sys/kernel.h> 61 #include <sys/kthread.h> 62 #include <sys/lockf.h> 63 #include <sys/malloc.h> 64 #include <sys/mount.h> 65 #include <sys/namei.h> 66 #include <sys/priv.h> 67 #include <sys/reboot.h> 68 #include <sys/sleepqueue.h> 69 #include <sys/stat.h> 70 #include <sys/sysctl.h> 71 #include <sys/syslog.h> 72 #include <sys/vmmeter.h> 73 #include <sys/vnode.h> 74 75 #include <machine/stdarg.h> 76 77 #include <security/mac/mac_framework.h> 78 79 #include <vm/vm.h> 80 #include <vm/vm_object.h> 81 #include <vm/vm_extern.h> 82 #include <vm/pmap.h> 83 #include <vm/vm_map.h> 84 #include <vm/vm_page.h> 85 #include <vm/vm_kern.h> 86 #include <vm/uma.h> 87 88 #ifdef DDB 89 #include <ddb/ddb.h> 90 #endif 91 92 #define WI_MPSAFEQ 0 93 #define WI_GIANTQ 1 94 95 static MALLOC_DEFINE(M_NETADDR, "subr_export_host", "Export host address structure"); 96 97 static void delmntque(struct vnode *vp); 98 static int flushbuflist(struct bufv *bufv, int flags, struct bufobj *bo, 99 int slpflag, int slptimeo); 100 static void syncer_shutdown(void *arg, int howto); 101 static int vtryrecycle(struct vnode *vp); 102 static void vbusy(struct vnode *vp); 103 static void vinactive(struct vnode *, struct thread *); 104 static void v_incr_usecount(struct vnode *); 105 static void v_decr_usecount(struct vnode *); 106 static void v_decr_useonly(struct vnode *); 107 static void v_upgrade_usecount(struct vnode *); 108 static void vfree(struct vnode *); 109 static void vnlru_free(int); 110 static void vgonel(struct vnode *); 111 static void vfs_knllock(void *arg); 112 static void vfs_knlunlock(void *arg); 113 static void vfs_knl_assert_locked(void *arg); 114 static void vfs_knl_assert_unlocked(void *arg); 115 static void destroy_vpollinfo(struct vpollinfo *vi); 116 117 /* 118 * Number of vnodes in existence. Increased whenever getnewvnode() 119 * allocates a new vnode, decreased on vdestroy() called on VI_DOOMed 120 * vnode. 121 */ 122 static unsigned long numvnodes; 123 124 SYSCTL_LONG(_vfs, OID_AUTO, numvnodes, CTLFLAG_RD, &numvnodes, 0, ""); 125 126 /* 127 * Conversion tables for conversion from vnode types to inode formats 128 * and back. 129 */ 130 enum vtype iftovt_tab[16] = { 131 VNON, VFIFO, VCHR, VNON, VDIR, VNON, VBLK, VNON, 132 VREG, VNON, VLNK, VNON, VSOCK, VNON, VNON, VBAD, 133 }; 134 int vttoif_tab[10] = { 135 0, S_IFREG, S_IFDIR, S_IFBLK, S_IFCHR, S_IFLNK, 136 S_IFSOCK, S_IFIFO, S_IFMT, S_IFMT 137 }; 138 139 /* 140 * List of vnodes that are ready for recycling. 141 */ 142 static TAILQ_HEAD(freelst, vnode) vnode_free_list; 143 144 /* 145 * Free vnode target. Free vnodes may simply be files which have been stat'd 146 * but not read. This is somewhat common, and a small cache of such files 147 * should be kept to avoid recreation costs. 148 */ 149 static u_long wantfreevnodes; 150 SYSCTL_LONG(_vfs, OID_AUTO, wantfreevnodes, CTLFLAG_RW, &wantfreevnodes, 0, ""); 151 /* Number of vnodes in the free list. */ 152 static u_long freevnodes; 153 SYSCTL_LONG(_vfs, OID_AUTO, freevnodes, CTLFLAG_RD, &freevnodes, 0, ""); 154 155 static int vlru_allow_cache_src; 156 SYSCTL_INT(_vfs, OID_AUTO, vlru_allow_cache_src, CTLFLAG_RW, 157 &vlru_allow_cache_src, 0, "Allow vlru to reclaim source vnode"); 158 159 /* 160 * Various variables used for debugging the new implementation of 161 * reassignbuf(). 162 * XXX these are probably of (very) limited utility now. 163 */ 164 static int reassignbufcalls; 165 SYSCTL_INT(_vfs, OID_AUTO, reassignbufcalls, CTLFLAG_RW, &reassignbufcalls, 0, ""); 166 167 /* 168 * Cache for the mount type id assigned to NFS. This is used for 169 * special checks in nfs/nfs_nqlease.c and vm/vnode_pager.c. 170 */ 171 int nfs_mount_type = -1; 172 173 /* To keep more than one thread at a time from running vfs_getnewfsid */ 174 static struct mtx mntid_mtx; 175 176 /* 177 * Lock for any access to the following: 178 * vnode_free_list 179 * numvnodes 180 * freevnodes 181 */ 182 static struct mtx vnode_free_list_mtx; 183 184 /* Publicly exported FS */ 185 struct nfs_public nfs_pub; 186 187 /* Zone for allocation of new vnodes - used exclusively by getnewvnode() */ 188 static uma_zone_t vnode_zone; 189 static uma_zone_t vnodepoll_zone; 190 191 /* Set to 1 to print out reclaim of active vnodes */ 192 int prtactive; 193 194 /* 195 * The workitem queue. 196 * 197 * It is useful to delay writes of file data and filesystem metadata 198 * for tens of seconds so that quickly created and deleted files need 199 * not waste disk bandwidth being created and removed. To realize this, 200 * we append vnodes to a "workitem" queue. When running with a soft 201 * updates implementation, most pending metadata dependencies should 202 * not wait for more than a few seconds. Thus, mounted on block devices 203 * are delayed only about a half the time that file data is delayed. 204 * Similarly, directory updates are more critical, so are only delayed 205 * about a third the time that file data is delayed. Thus, there are 206 * SYNCER_MAXDELAY queues that are processed round-robin at a rate of 207 * one each second (driven off the filesystem syncer process). The 208 * syncer_delayno variable indicates the next queue that is to be processed. 209 * Items that need to be processed soon are placed in this queue: 210 * 211 * syncer_workitem_pending[syncer_delayno] 212 * 213 * A delay of fifteen seconds is done by placing the request fifteen 214 * entries later in the queue: 215 * 216 * syncer_workitem_pending[(syncer_delayno + 15) & syncer_mask] 217 * 218 */ 219 static int syncer_delayno; 220 static long syncer_mask; 221 LIST_HEAD(synclist, bufobj); 222 static struct synclist *syncer_workitem_pending[2]; 223 /* 224 * The sync_mtx protects: 225 * bo->bo_synclist 226 * sync_vnode_count 227 * syncer_delayno 228 * syncer_state 229 * syncer_workitem_pending 230 * syncer_worklist_len 231 * rushjob 232 */ 233 static struct mtx sync_mtx; 234 static struct cv sync_wakeup; 235 236 #define SYNCER_MAXDELAY 32 237 static int syncer_maxdelay = SYNCER_MAXDELAY; /* maximum delay time */ 238 static int syncdelay = 30; /* max time to delay syncing data */ 239 static int filedelay = 30; /* time to delay syncing files */ 240 SYSCTL_INT(_kern, OID_AUTO, filedelay, CTLFLAG_RW, &filedelay, 0, ""); 241 static int dirdelay = 29; /* time to delay syncing directories */ 242 SYSCTL_INT(_kern, OID_AUTO, dirdelay, CTLFLAG_RW, &dirdelay, 0, ""); 243 static int metadelay = 28; /* time to delay syncing metadata */ 244 SYSCTL_INT(_kern, OID_AUTO, metadelay, CTLFLAG_RW, &metadelay, 0, ""); 245 static int rushjob; /* number of slots to run ASAP */ 246 static int stat_rush_requests; /* number of times I/O speeded up */ 247 SYSCTL_INT(_debug, OID_AUTO, rush_requests, CTLFLAG_RW, &stat_rush_requests, 0, ""); 248 249 /* 250 * When shutting down the syncer, run it at four times normal speed. 251 */ 252 #define SYNCER_SHUTDOWN_SPEEDUP 4 253 static int sync_vnode_count; 254 static int syncer_worklist_len; 255 static enum { SYNCER_RUNNING, SYNCER_SHUTTING_DOWN, SYNCER_FINAL_DELAY } 256 syncer_state; 257 258 /* 259 * Number of vnodes we want to exist at any one time. This is mostly used 260 * to size hash tables in vnode-related code. It is normally not used in 261 * getnewvnode(), as wantfreevnodes is normally nonzero.) 262 * 263 * XXX desiredvnodes is historical cruft and should not exist. 264 */ 265 int desiredvnodes; 266 SYSCTL_INT(_kern, KERN_MAXVNODES, maxvnodes, CTLFLAG_RW, 267 &desiredvnodes, 0, "Maximum number of vnodes"); 268 SYSCTL_INT(_kern, OID_AUTO, minvnodes, CTLFLAG_RW, 269 &wantfreevnodes, 0, "Minimum number of vnodes (legacy)"); 270 static int vnlru_nowhere; 271 SYSCTL_INT(_debug, OID_AUTO, vnlru_nowhere, CTLFLAG_RW, 272 &vnlru_nowhere, 0, "Number of times the vnlru process ran without success"); 273 274 /* 275 * Macros to control when a vnode is freed and recycled. All require 276 * the vnode interlock. 277 */ 278 #define VCANRECYCLE(vp) (((vp)->v_iflag & VI_FREE) && !(vp)->v_holdcnt) 279 #define VSHOULDFREE(vp) (!((vp)->v_iflag & VI_FREE) && !(vp)->v_holdcnt) 280 #define VSHOULDBUSY(vp) (((vp)->v_iflag & VI_FREE) && (vp)->v_holdcnt) 281 282 283 /* 284 * Initialize the vnode management data structures. 285 */ 286 #ifndef MAXVNODES_MAX 287 #define MAXVNODES_MAX 100000 288 #endif 289 static void 290 vntblinit(void *dummy __unused) 291 { 292 293 /* 294 * Desiredvnodes is a function of the physical memory size and 295 * the kernel's heap size. Specifically, desiredvnodes scales 296 * in proportion to the physical memory size until two fifths 297 * of the kernel's heap size is consumed by vnodes and vm 298 * objects. 299 */ 300 desiredvnodes = min(maxproc + cnt.v_page_count / 4, 2 * vm_kmem_size / 301 (5 * (sizeof(struct vm_object) + sizeof(struct vnode)))); 302 if (desiredvnodes > MAXVNODES_MAX) { 303 if (bootverbose) 304 printf("Reducing kern.maxvnodes %d -> %d\n", 305 desiredvnodes, MAXVNODES_MAX); 306 desiredvnodes = MAXVNODES_MAX; 307 } 308 wantfreevnodes = desiredvnodes / 4; 309 mtx_init(&mntid_mtx, "mntid", NULL, MTX_DEF); 310 TAILQ_INIT(&vnode_free_list); 311 mtx_init(&vnode_free_list_mtx, "vnode_free_list", NULL, MTX_DEF); 312 vnode_zone = uma_zcreate("VNODE", sizeof (struct vnode), NULL, NULL, 313 NULL, NULL, UMA_ALIGN_PTR, 0); 314 vnodepoll_zone = uma_zcreate("VNODEPOLL", sizeof (struct vpollinfo), 315 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); 316 /* 317 * Initialize the filesystem syncer. 318 */ 319 syncer_workitem_pending[WI_MPSAFEQ] = hashinit(syncer_maxdelay, M_VNODE, 320 &syncer_mask); 321 syncer_workitem_pending[WI_GIANTQ] = hashinit(syncer_maxdelay, M_VNODE, 322 &syncer_mask); 323 syncer_maxdelay = syncer_mask + 1; 324 mtx_init(&sync_mtx, "Syncer mtx", NULL, MTX_DEF); 325 cv_init(&sync_wakeup, "syncer"); 326 } 327 SYSINIT(vfs, SI_SUB_VFS, SI_ORDER_FIRST, vntblinit, NULL); 328 329 330 /* 331 * Mark a mount point as busy. Used to synchronize access and to delay 332 * unmounting. Eventually, mountlist_mtx is not released on failure. 333 */ 334 int 335 vfs_busy(struct mount *mp, int flags) 336 { 337 338 MPASS((flags & ~MBF_MASK) == 0); 339 CTR3(KTR_VFS, "%s: mp %p with flags %d", __func__, mp, flags); 340 341 MNT_ILOCK(mp); 342 MNT_REF(mp); 343 /* 344 * If mount point is currenly being unmounted, sleep until the 345 * mount point fate is decided. If thread doing the unmounting fails, 346 * it will clear MNTK_UNMOUNT flag before waking us up, indicating 347 * that this mount point has survived the unmount attempt and vfs_busy 348 * should retry. Otherwise the unmounter thread will set MNTK_REFEXPIRE 349 * flag in addition to MNTK_UNMOUNT, indicating that mount point is 350 * about to be really destroyed. vfs_busy needs to release its 351 * reference on the mount point in this case and return with ENOENT, 352 * telling the caller that mount mount it tried to busy is no longer 353 * valid. 354 */ 355 while (mp->mnt_kern_flag & MNTK_UNMOUNT) { 356 if (flags & MBF_NOWAIT || mp->mnt_kern_flag & MNTK_REFEXPIRE) { 357 MNT_REL(mp); 358 MNT_IUNLOCK(mp); 359 CTR1(KTR_VFS, "%s: failed busying before sleeping", 360 __func__); 361 return (ENOENT); 362 } 363 if (flags & MBF_MNTLSTLOCK) 364 mtx_unlock(&mountlist_mtx); 365 mp->mnt_kern_flag |= MNTK_MWAIT; 366 msleep(mp, MNT_MTX(mp), PVFS, "vfs_busy", 0); 367 if (flags & MBF_MNTLSTLOCK) 368 mtx_lock(&mountlist_mtx); 369 } 370 if (flags & MBF_MNTLSTLOCK) 371 mtx_unlock(&mountlist_mtx); 372 mp->mnt_lockref++; 373 MNT_IUNLOCK(mp); 374 return (0); 375 } 376 377 /* 378 * Free a busy filesystem. 379 */ 380 void 381 vfs_unbusy(struct mount *mp) 382 { 383 384 CTR2(KTR_VFS, "%s: mp %p", __func__, mp); 385 MNT_ILOCK(mp); 386 MNT_REL(mp); 387 KASSERT(mp->mnt_lockref > 0, ("negative mnt_lockref")); 388 mp->mnt_lockref--; 389 if (mp->mnt_lockref == 0 && (mp->mnt_kern_flag & MNTK_DRAINING) != 0) { 390 MPASS(mp->mnt_kern_flag & MNTK_UNMOUNT); 391 CTR1(KTR_VFS, "%s: waking up waiters", __func__); 392 mp->mnt_kern_flag &= ~MNTK_DRAINING; 393 wakeup(&mp->mnt_lockref); 394 } 395 MNT_IUNLOCK(mp); 396 } 397 398 /* 399 * Lookup a mount point by filesystem identifier. 400 */ 401 struct mount * 402 vfs_getvfs(fsid_t *fsid) 403 { 404 struct mount *mp; 405 406 CTR2(KTR_VFS, "%s: fsid %p", __func__, fsid); 407 mtx_lock(&mountlist_mtx); 408 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 409 if (mp->mnt_stat.f_fsid.val[0] == fsid->val[0] && 410 mp->mnt_stat.f_fsid.val[1] == fsid->val[1]) { 411 vfs_ref(mp); 412 mtx_unlock(&mountlist_mtx); 413 return (mp); 414 } 415 } 416 mtx_unlock(&mountlist_mtx); 417 CTR2(KTR_VFS, "%s: lookup failed for %p id", __func__, fsid); 418 return ((struct mount *) 0); 419 } 420 421 /* 422 * Lookup a mount point by filesystem identifier, busying it before 423 * returning. 424 */ 425 struct mount * 426 vfs_busyfs(fsid_t *fsid) 427 { 428 struct mount *mp; 429 int error; 430 431 CTR2(KTR_VFS, "%s: fsid %p", __func__, fsid); 432 mtx_lock(&mountlist_mtx); 433 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 434 if (mp->mnt_stat.f_fsid.val[0] == fsid->val[0] && 435 mp->mnt_stat.f_fsid.val[1] == fsid->val[1]) { 436 error = vfs_busy(mp, MBF_MNTLSTLOCK); 437 if (error) { 438 mtx_unlock(&mountlist_mtx); 439 return (NULL); 440 } 441 return (mp); 442 } 443 } 444 CTR2(KTR_VFS, "%s: lookup failed for %p id", __func__, fsid); 445 mtx_unlock(&mountlist_mtx); 446 return ((struct mount *) 0); 447 } 448 449 /* 450 * Check if a user can access privileged mount options. 451 */ 452 int 453 vfs_suser(struct mount *mp, struct thread *td) 454 { 455 int error; 456 457 /* 458 * If the thread is jailed, but this is not a jail-friendly file 459 * system, deny immediately. 460 */ 461 if (!(mp->mnt_vfc->vfc_flags & VFCF_JAIL) && jailed(td->td_ucred)) 462 return (EPERM); 463 464 /* 465 * If the file system was mounted outside the jail of the calling 466 * thread, deny immediately. 467 */ 468 if (prison_check(td->td_ucred, mp->mnt_cred) != 0) 469 return (EPERM); 470 471 /* 472 * If file system supports delegated administration, we don't check 473 * for the PRIV_VFS_MOUNT_OWNER privilege - it will be better verified 474 * by the file system itself. 475 * If this is not the user that did original mount, we check for 476 * the PRIV_VFS_MOUNT_OWNER privilege. 477 */ 478 if (!(mp->mnt_vfc->vfc_flags & VFCF_DELEGADMIN) && 479 mp->mnt_cred->cr_uid != td->td_ucred->cr_uid) { 480 if ((error = priv_check(td, PRIV_VFS_MOUNT_OWNER)) != 0) 481 return (error); 482 } 483 return (0); 484 } 485 486 /* 487 * Get a new unique fsid. Try to make its val[0] unique, since this value 488 * will be used to create fake device numbers for stat(). Also try (but 489 * not so hard) make its val[0] unique mod 2^16, since some emulators only 490 * support 16-bit device numbers. We end up with unique val[0]'s for the 491 * first 2^16 calls and unique val[0]'s mod 2^16 for the first 2^8 calls. 492 * 493 * Keep in mind that several mounts may be running in parallel. Starting 494 * the search one past where the previous search terminated is both a 495 * micro-optimization and a defense against returning the same fsid to 496 * different mounts. 497 */ 498 void 499 vfs_getnewfsid(struct mount *mp) 500 { 501 static u_int16_t mntid_base; 502 struct mount *nmp; 503 fsid_t tfsid; 504 int mtype; 505 506 CTR2(KTR_VFS, "%s: mp %p", __func__, mp); 507 mtx_lock(&mntid_mtx); 508 mtype = mp->mnt_vfc->vfc_typenum; 509 tfsid.val[1] = mtype; 510 mtype = (mtype & 0xFF) << 24; 511 for (;;) { 512 tfsid.val[0] = makedev(255, 513 mtype | ((mntid_base & 0xFF00) << 8) | (mntid_base & 0xFF)); 514 mntid_base++; 515 if ((nmp = vfs_getvfs(&tfsid)) == NULL) 516 break; 517 vfs_rel(nmp); 518 } 519 mp->mnt_stat.f_fsid.val[0] = tfsid.val[0]; 520 mp->mnt_stat.f_fsid.val[1] = tfsid.val[1]; 521 mtx_unlock(&mntid_mtx); 522 } 523 524 /* 525 * Knob to control the precision of file timestamps: 526 * 527 * 0 = seconds only; nanoseconds zeroed. 528 * 1 = seconds and nanoseconds, accurate within 1/HZ. 529 * 2 = seconds and nanoseconds, truncated to microseconds. 530 * >=3 = seconds and nanoseconds, maximum precision. 531 */ 532 enum { TSP_SEC, TSP_HZ, TSP_USEC, TSP_NSEC }; 533 534 static int timestamp_precision = TSP_SEC; 535 SYSCTL_INT(_vfs, OID_AUTO, timestamp_precision, CTLFLAG_RW, 536 ×tamp_precision, 0, ""); 537 538 /* 539 * Get a current timestamp. 540 */ 541 void 542 vfs_timestamp(struct timespec *tsp) 543 { 544 struct timeval tv; 545 546 switch (timestamp_precision) { 547 case TSP_SEC: 548 tsp->tv_sec = time_second; 549 tsp->tv_nsec = 0; 550 break; 551 case TSP_HZ: 552 getnanotime(tsp); 553 break; 554 case TSP_USEC: 555 microtime(&tv); 556 TIMEVAL_TO_TIMESPEC(&tv, tsp); 557 break; 558 case TSP_NSEC: 559 default: 560 nanotime(tsp); 561 break; 562 } 563 } 564 565 /* 566 * Set vnode attributes to VNOVAL 567 */ 568 void 569 vattr_null(struct vattr *vap) 570 { 571 572 vap->va_type = VNON; 573 vap->va_size = VNOVAL; 574 vap->va_bytes = VNOVAL; 575 vap->va_mode = VNOVAL; 576 vap->va_nlink = VNOVAL; 577 vap->va_uid = VNOVAL; 578 vap->va_gid = VNOVAL; 579 vap->va_fsid = VNOVAL; 580 vap->va_fileid = VNOVAL; 581 vap->va_blocksize = VNOVAL; 582 vap->va_rdev = VNOVAL; 583 vap->va_atime.tv_sec = VNOVAL; 584 vap->va_atime.tv_nsec = VNOVAL; 585 vap->va_mtime.tv_sec = VNOVAL; 586 vap->va_mtime.tv_nsec = VNOVAL; 587 vap->va_ctime.tv_sec = VNOVAL; 588 vap->va_ctime.tv_nsec = VNOVAL; 589 vap->va_birthtime.tv_sec = VNOVAL; 590 vap->va_birthtime.tv_nsec = VNOVAL; 591 vap->va_flags = VNOVAL; 592 vap->va_gen = VNOVAL; 593 vap->va_vaflags = 0; 594 } 595 596 /* 597 * This routine is called when we have too many vnodes. It attempts 598 * to free <count> vnodes and will potentially free vnodes that still 599 * have VM backing store (VM backing store is typically the cause 600 * of a vnode blowout so we want to do this). Therefore, this operation 601 * is not considered cheap. 602 * 603 * A number of conditions may prevent a vnode from being reclaimed. 604 * the buffer cache may have references on the vnode, a directory 605 * vnode may still have references due to the namei cache representing 606 * underlying files, or the vnode may be in active use. It is not 607 * desireable to reuse such vnodes. These conditions may cause the 608 * number of vnodes to reach some minimum value regardless of what 609 * you set kern.maxvnodes to. Do not set kern.maxvnodes too low. 610 */ 611 static int 612 vlrureclaim(struct mount *mp) 613 { 614 struct vnode *vp; 615 int done; 616 int trigger; 617 int usevnodes; 618 int count; 619 620 /* 621 * Calculate the trigger point, don't allow user 622 * screwups to blow us up. This prevents us from 623 * recycling vnodes with lots of resident pages. We 624 * aren't trying to free memory, we are trying to 625 * free vnodes. 626 */ 627 usevnodes = desiredvnodes; 628 if (usevnodes <= 0) 629 usevnodes = 1; 630 trigger = cnt.v_page_count * 2 / usevnodes; 631 done = 0; 632 vn_start_write(NULL, &mp, V_WAIT); 633 MNT_ILOCK(mp); 634 count = mp->mnt_nvnodelistsize / 10 + 1; 635 while (count != 0) { 636 vp = TAILQ_FIRST(&mp->mnt_nvnodelist); 637 while (vp != NULL && vp->v_type == VMARKER) 638 vp = TAILQ_NEXT(vp, v_nmntvnodes); 639 if (vp == NULL) 640 break; 641 TAILQ_REMOVE(&mp->mnt_nvnodelist, vp, v_nmntvnodes); 642 TAILQ_INSERT_TAIL(&mp->mnt_nvnodelist, vp, v_nmntvnodes); 643 --count; 644 if (!VI_TRYLOCK(vp)) 645 goto next_iter; 646 /* 647 * If it's been deconstructed already, it's still 648 * referenced, or it exceeds the trigger, skip it. 649 */ 650 if (vp->v_usecount || 651 (!vlru_allow_cache_src && 652 !LIST_EMPTY(&(vp)->v_cache_src)) || 653 (vp->v_iflag & VI_DOOMED) != 0 || (vp->v_object != NULL && 654 vp->v_object->resident_page_count > trigger)) { 655 VI_UNLOCK(vp); 656 goto next_iter; 657 } 658 MNT_IUNLOCK(mp); 659 vholdl(vp); 660 if (VOP_LOCK(vp, LK_INTERLOCK|LK_EXCLUSIVE|LK_NOWAIT)) { 661 vdrop(vp); 662 goto next_iter_mntunlocked; 663 } 664 VI_LOCK(vp); 665 /* 666 * v_usecount may have been bumped after VOP_LOCK() dropped 667 * the vnode interlock and before it was locked again. 668 * 669 * It is not necessary to recheck VI_DOOMED because it can 670 * only be set by another thread that holds both the vnode 671 * lock and vnode interlock. If another thread has the 672 * vnode lock before we get to VOP_LOCK() and obtains the 673 * vnode interlock after VOP_LOCK() drops the vnode 674 * interlock, the other thread will be unable to drop the 675 * vnode lock before our VOP_LOCK() call fails. 676 */ 677 if (vp->v_usecount || 678 (!vlru_allow_cache_src && 679 !LIST_EMPTY(&(vp)->v_cache_src)) || 680 (vp->v_object != NULL && 681 vp->v_object->resident_page_count > trigger)) { 682 VOP_UNLOCK(vp, LK_INTERLOCK); 683 goto next_iter_mntunlocked; 684 } 685 KASSERT((vp->v_iflag & VI_DOOMED) == 0, 686 ("VI_DOOMED unexpectedly detected in vlrureclaim()")); 687 vgonel(vp); 688 VOP_UNLOCK(vp, 0); 689 vdropl(vp); 690 done++; 691 next_iter_mntunlocked: 692 if ((count % 256) != 0) 693 goto relock_mnt; 694 goto yield; 695 next_iter: 696 if ((count % 256) != 0) 697 continue; 698 MNT_IUNLOCK(mp); 699 yield: 700 uio_yield(); 701 relock_mnt: 702 MNT_ILOCK(mp); 703 } 704 MNT_IUNLOCK(mp); 705 vn_finished_write(mp); 706 return done; 707 } 708 709 /* 710 * Attempt to keep the free list at wantfreevnodes length. 711 */ 712 static void 713 vnlru_free(int count) 714 { 715 struct vnode *vp; 716 int vfslocked; 717 718 mtx_assert(&vnode_free_list_mtx, MA_OWNED); 719 for (; count > 0; count--) { 720 vp = TAILQ_FIRST(&vnode_free_list); 721 /* 722 * The list can be modified while the free_list_mtx 723 * has been dropped and vp could be NULL here. 724 */ 725 if (!vp) 726 break; 727 VNASSERT(vp->v_op != NULL, vp, 728 ("vnlru_free: vnode already reclaimed.")); 729 TAILQ_REMOVE(&vnode_free_list, vp, v_freelist); 730 /* 731 * Don't recycle if we can't get the interlock. 732 */ 733 if (!VI_TRYLOCK(vp)) { 734 TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_freelist); 735 continue; 736 } 737 VNASSERT(VCANRECYCLE(vp), vp, 738 ("vp inconsistent on freelist")); 739 freevnodes--; 740 vp->v_iflag &= ~VI_FREE; 741 vholdl(vp); 742 mtx_unlock(&vnode_free_list_mtx); 743 VI_UNLOCK(vp); 744 vfslocked = VFS_LOCK_GIANT(vp->v_mount); 745 vtryrecycle(vp); 746 VFS_UNLOCK_GIANT(vfslocked); 747 /* 748 * If the recycled succeeded this vdrop will actually free 749 * the vnode. If not it will simply place it back on 750 * the free list. 751 */ 752 vdrop(vp); 753 mtx_lock(&vnode_free_list_mtx); 754 } 755 } 756 /* 757 * Attempt to recycle vnodes in a context that is always safe to block. 758 * Calling vlrurecycle() from the bowels of filesystem code has some 759 * interesting deadlock problems. 760 */ 761 static struct proc *vnlruproc; 762 static int vnlruproc_sig; 763 764 static void 765 vnlru_proc(void) 766 { 767 struct mount *mp, *nmp; 768 int done, vfslocked; 769 struct proc *p = vnlruproc; 770 771 EVENTHANDLER_REGISTER(shutdown_pre_sync, kproc_shutdown, p, 772 SHUTDOWN_PRI_FIRST); 773 774 for (;;) { 775 kproc_suspend_check(p); 776 mtx_lock(&vnode_free_list_mtx); 777 if (freevnodes > wantfreevnodes) 778 vnlru_free(freevnodes - wantfreevnodes); 779 if (numvnodes <= desiredvnodes * 9 / 10) { 780 vnlruproc_sig = 0; 781 wakeup(&vnlruproc_sig); 782 msleep(vnlruproc, &vnode_free_list_mtx, 783 PVFS|PDROP, "vlruwt", hz); 784 continue; 785 } 786 mtx_unlock(&vnode_free_list_mtx); 787 done = 0; 788 mtx_lock(&mountlist_mtx); 789 for (mp = TAILQ_FIRST(&mountlist); mp != NULL; mp = nmp) { 790 if (vfs_busy(mp, MBF_NOWAIT | MBF_MNTLSTLOCK)) { 791 nmp = TAILQ_NEXT(mp, mnt_list); 792 continue; 793 } 794 vfslocked = VFS_LOCK_GIANT(mp); 795 done += vlrureclaim(mp); 796 VFS_UNLOCK_GIANT(vfslocked); 797 mtx_lock(&mountlist_mtx); 798 nmp = TAILQ_NEXT(mp, mnt_list); 799 vfs_unbusy(mp); 800 } 801 mtx_unlock(&mountlist_mtx); 802 if (done == 0) { 803 #if 0 804 /* These messages are temporary debugging aids */ 805 if (vnlru_nowhere < 5) 806 printf("vnlru process getting nowhere..\n"); 807 else if (vnlru_nowhere == 5) 808 printf("vnlru process messages stopped.\n"); 809 #endif 810 vnlru_nowhere++; 811 tsleep(vnlruproc, PPAUSE, "vlrup", hz * 3); 812 } else 813 uio_yield(); 814 } 815 } 816 817 static struct kproc_desc vnlru_kp = { 818 "vnlru", 819 vnlru_proc, 820 &vnlruproc 821 }; 822 SYSINIT(vnlru, SI_SUB_KTHREAD_UPDATE, SI_ORDER_FIRST, kproc_start, 823 &vnlru_kp); 824 825 static void 826 vfs_lowmem(void *arg __unused) 827 { 828 829 /* 830 * On low memory condition free 1/8th of the free vnodes. 831 */ 832 mtx_lock(&vnode_free_list_mtx); 833 vnlru_free(freevnodes / 8); 834 mtx_unlock(&vnode_free_list_mtx); 835 } 836 EVENTHANDLER_DEFINE(vm_lowmem, vfs_lowmem, NULL, 0); 837 838 /* 839 * Routines having to do with the management of the vnode table. 840 */ 841 842 void 843 vdestroy(struct vnode *vp) 844 { 845 struct bufobj *bo; 846 847 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 848 mtx_lock(&vnode_free_list_mtx); 849 numvnodes--; 850 mtx_unlock(&vnode_free_list_mtx); 851 bo = &vp->v_bufobj; 852 VNASSERT((vp->v_iflag & VI_FREE) == 0, vp, 853 ("cleaned vnode still on the free list.")); 854 VNASSERT(vp->v_data == NULL, vp, ("cleaned vnode isn't")); 855 VNASSERT(vp->v_holdcnt == 0, vp, ("Non-zero hold count")); 856 VNASSERT(vp->v_usecount == 0, vp, ("Non-zero use count")); 857 VNASSERT(vp->v_writecount == 0, vp, ("Non-zero write count")); 858 VNASSERT(bo->bo_numoutput == 0, vp, ("Clean vnode has pending I/O's")); 859 VNASSERT(bo->bo_clean.bv_cnt == 0, vp, ("cleanbufcnt not 0")); 860 VNASSERT(bo->bo_clean.bv_root == NULL, vp, ("cleanblkroot not NULL")); 861 VNASSERT(bo->bo_dirty.bv_cnt == 0, vp, ("dirtybufcnt not 0")); 862 VNASSERT(bo->bo_dirty.bv_root == NULL, vp, ("dirtyblkroot not NULL")); 863 VNASSERT(TAILQ_EMPTY(&vp->v_cache_dst), vp, ("vp has namecache dst")); 864 VNASSERT(LIST_EMPTY(&vp->v_cache_src), vp, ("vp has namecache src")); 865 VNASSERT(vp->v_cache_dd == NULL, vp, ("vp has namecache for ..")); 866 VI_UNLOCK(vp); 867 #ifdef MAC 868 mac_vnode_destroy(vp); 869 #endif 870 if (vp->v_pollinfo != NULL) 871 destroy_vpollinfo(vp->v_pollinfo); 872 #ifdef INVARIANTS 873 /* XXX Elsewhere we can detect an already freed vnode via NULL v_op. */ 874 vp->v_op = NULL; 875 #endif 876 lockdestroy(vp->v_vnlock); 877 mtx_destroy(&vp->v_interlock); 878 mtx_destroy(BO_MTX(bo)); 879 uma_zfree(vnode_zone, vp); 880 } 881 882 /* 883 * Try to recycle a freed vnode. We abort if anyone picks up a reference 884 * before we actually vgone(). This function must be called with the vnode 885 * held to prevent the vnode from being returned to the free list midway 886 * through vgone(). 887 */ 888 static int 889 vtryrecycle(struct vnode *vp) 890 { 891 struct mount *vnmp; 892 893 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 894 VNASSERT(vp->v_holdcnt, vp, 895 ("vtryrecycle: Recycling vp %p without a reference.", vp)); 896 /* 897 * This vnode may found and locked via some other list, if so we 898 * can't recycle it yet. 899 */ 900 if (VOP_LOCK(vp, LK_EXCLUSIVE | LK_NOWAIT) != 0) { 901 CTR2(KTR_VFS, 902 "%s: impossible to recycle, vp %p lock is already held", 903 __func__, vp); 904 return (EWOULDBLOCK); 905 } 906 /* 907 * Don't recycle if its filesystem is being suspended. 908 */ 909 if (vn_start_write(vp, &vnmp, V_NOWAIT) != 0) { 910 VOP_UNLOCK(vp, 0); 911 CTR2(KTR_VFS, 912 "%s: impossible to recycle, cannot start the write for %p", 913 __func__, vp); 914 return (EBUSY); 915 } 916 /* 917 * If we got this far, we need to acquire the interlock and see if 918 * anyone picked up this vnode from another list. If not, we will 919 * mark it with DOOMED via vgonel() so that anyone who does find it 920 * will skip over it. 921 */ 922 VI_LOCK(vp); 923 if (vp->v_usecount) { 924 VOP_UNLOCK(vp, LK_INTERLOCK); 925 vn_finished_write(vnmp); 926 CTR2(KTR_VFS, 927 "%s: impossible to recycle, %p is already referenced", 928 __func__, vp); 929 return (EBUSY); 930 } 931 if ((vp->v_iflag & VI_DOOMED) == 0) 932 vgonel(vp); 933 VOP_UNLOCK(vp, LK_INTERLOCK); 934 vn_finished_write(vnmp); 935 return (0); 936 } 937 938 /* 939 * Return the next vnode from the free list. 940 */ 941 int 942 getnewvnode(const char *tag, struct mount *mp, struct vop_vector *vops, 943 struct vnode **vpp) 944 { 945 struct vnode *vp = NULL; 946 struct bufobj *bo; 947 948 CTR3(KTR_VFS, "%s: mp %p with tag %s", __func__, mp, tag); 949 mtx_lock(&vnode_free_list_mtx); 950 /* 951 * Lend our context to reclaim vnodes if they've exceeded the max. 952 */ 953 if (freevnodes > wantfreevnodes) 954 vnlru_free(1); 955 /* 956 * Wait for available vnodes. 957 */ 958 if (numvnodes > desiredvnodes) { 959 if (mp != NULL && (mp->mnt_kern_flag & MNTK_SUSPEND)) { 960 /* 961 * File system is beeing suspended, we cannot risk a 962 * deadlock here, so allocate new vnode anyway. 963 */ 964 if (freevnodes > wantfreevnodes) 965 vnlru_free(freevnodes - wantfreevnodes); 966 goto alloc; 967 } 968 if (vnlruproc_sig == 0) { 969 vnlruproc_sig = 1; /* avoid unnecessary wakeups */ 970 wakeup(vnlruproc); 971 } 972 msleep(&vnlruproc_sig, &vnode_free_list_mtx, PVFS, 973 "vlruwk", hz); 974 #if 0 /* XXX Not all VFS_VGET/ffs_vget callers check returns. */ 975 if (numvnodes > desiredvnodes) { 976 mtx_unlock(&vnode_free_list_mtx); 977 return (ENFILE); 978 } 979 #endif 980 } 981 alloc: 982 numvnodes++; 983 mtx_unlock(&vnode_free_list_mtx); 984 vp = (struct vnode *) uma_zalloc(vnode_zone, M_WAITOK|M_ZERO); 985 /* 986 * Setup locks. 987 */ 988 vp->v_vnlock = &vp->v_lock; 989 mtx_init(&vp->v_interlock, "vnode interlock", NULL, MTX_DEF); 990 /* 991 * By default, don't allow shared locks unless filesystems 992 * opt-in. 993 */ 994 lockinit(vp->v_vnlock, PVFS, tag, VLKTIMEOUT, LK_NOSHARE); 995 /* 996 * Initialize bufobj. 997 */ 998 bo = &vp->v_bufobj; 999 bo->__bo_vnode = vp; 1000 mtx_init(BO_MTX(bo), "bufobj interlock", NULL, MTX_DEF); 1001 bo->bo_ops = &buf_ops_bio; 1002 bo->bo_private = vp; 1003 TAILQ_INIT(&bo->bo_clean.bv_hd); 1004 TAILQ_INIT(&bo->bo_dirty.bv_hd); 1005 /* 1006 * Initialize namecache. 1007 */ 1008 LIST_INIT(&vp->v_cache_src); 1009 TAILQ_INIT(&vp->v_cache_dst); 1010 /* 1011 * Finalize various vnode identity bits. 1012 */ 1013 vp->v_type = VNON; 1014 vp->v_tag = tag; 1015 vp->v_op = vops; 1016 v_incr_usecount(vp); 1017 vp->v_data = 0; 1018 #ifdef MAC 1019 mac_vnode_init(vp); 1020 if (mp != NULL && (mp->mnt_flag & MNT_MULTILABEL) == 0) 1021 mac_vnode_associate_singlelabel(mp, vp); 1022 else if (mp == NULL && vops != &dead_vnodeops) 1023 printf("NULL mp in getnewvnode()\n"); 1024 #endif 1025 if (mp != NULL) { 1026 bo->bo_bsize = mp->mnt_stat.f_iosize; 1027 if ((mp->mnt_kern_flag & MNTK_NOKNOTE) != 0) 1028 vp->v_vflag |= VV_NOKNOTE; 1029 } 1030 1031 *vpp = vp; 1032 return (0); 1033 } 1034 1035 /* 1036 * Delete from old mount point vnode list, if on one. 1037 */ 1038 static void 1039 delmntque(struct vnode *vp) 1040 { 1041 struct mount *mp; 1042 1043 mp = vp->v_mount; 1044 if (mp == NULL) 1045 return; 1046 MNT_ILOCK(mp); 1047 vp->v_mount = NULL; 1048 VNASSERT(mp->mnt_nvnodelistsize > 0, vp, 1049 ("bad mount point vnode list size")); 1050 TAILQ_REMOVE(&mp->mnt_nvnodelist, vp, v_nmntvnodes); 1051 mp->mnt_nvnodelistsize--; 1052 MNT_REL(mp); 1053 MNT_IUNLOCK(mp); 1054 } 1055 1056 static void 1057 insmntque_stddtr(struct vnode *vp, void *dtr_arg) 1058 { 1059 1060 vp->v_data = NULL; 1061 vp->v_op = &dead_vnodeops; 1062 /* XXX non mp-safe fs may still call insmntque with vnode 1063 unlocked */ 1064 if (!VOP_ISLOCKED(vp)) 1065 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 1066 vgone(vp); 1067 vput(vp); 1068 } 1069 1070 /* 1071 * Insert into list of vnodes for the new mount point, if available. 1072 */ 1073 int 1074 insmntque1(struct vnode *vp, struct mount *mp, 1075 void (*dtr)(struct vnode *, void *), void *dtr_arg) 1076 { 1077 int locked; 1078 1079 KASSERT(vp->v_mount == NULL, 1080 ("insmntque: vnode already on per mount vnode list")); 1081 VNASSERT(mp != NULL, vp, ("Don't call insmntque(foo, NULL)")); 1082 #ifdef DEBUG_VFS_LOCKS 1083 if (!VFS_NEEDSGIANT(mp)) 1084 ASSERT_VOP_ELOCKED(vp, 1085 "insmntque: mp-safe fs and non-locked vp"); 1086 #endif 1087 MNT_ILOCK(mp); 1088 if ((mp->mnt_kern_flag & MNTK_NOINSMNTQ) != 0 && 1089 ((mp->mnt_kern_flag & MNTK_UNMOUNTF) != 0 || 1090 mp->mnt_nvnodelistsize == 0)) { 1091 locked = VOP_ISLOCKED(vp); 1092 if (!locked || (locked == LK_EXCLUSIVE && 1093 (vp->v_vflag & VV_FORCEINSMQ) == 0)) { 1094 MNT_IUNLOCK(mp); 1095 if (dtr != NULL) 1096 dtr(vp, dtr_arg); 1097 return (EBUSY); 1098 } 1099 } 1100 vp->v_mount = mp; 1101 MNT_REF(mp); 1102 TAILQ_INSERT_TAIL(&mp->mnt_nvnodelist, vp, v_nmntvnodes); 1103 VNASSERT(mp->mnt_nvnodelistsize >= 0, vp, 1104 ("neg mount point vnode list size")); 1105 mp->mnt_nvnodelistsize++; 1106 MNT_IUNLOCK(mp); 1107 return (0); 1108 } 1109 1110 int 1111 insmntque(struct vnode *vp, struct mount *mp) 1112 { 1113 1114 return (insmntque1(vp, mp, insmntque_stddtr, NULL)); 1115 } 1116 1117 /* 1118 * Flush out and invalidate all buffers associated with a bufobj 1119 * Called with the underlying object locked. 1120 */ 1121 int 1122 bufobj_invalbuf(struct bufobj *bo, int flags, int slpflag, int slptimeo) 1123 { 1124 int error; 1125 1126 BO_LOCK(bo); 1127 if (flags & V_SAVE) { 1128 error = bufobj_wwait(bo, slpflag, slptimeo); 1129 if (error) { 1130 BO_UNLOCK(bo); 1131 return (error); 1132 } 1133 if (bo->bo_dirty.bv_cnt > 0) { 1134 BO_UNLOCK(bo); 1135 if ((error = BO_SYNC(bo, MNT_WAIT)) != 0) 1136 return (error); 1137 /* 1138 * XXX We could save a lock/unlock if this was only 1139 * enabled under INVARIANTS 1140 */ 1141 BO_LOCK(bo); 1142 if (bo->bo_numoutput > 0 || bo->bo_dirty.bv_cnt > 0) 1143 panic("vinvalbuf: dirty bufs"); 1144 } 1145 } 1146 /* 1147 * If you alter this loop please notice that interlock is dropped and 1148 * reacquired in flushbuflist. Special care is needed to ensure that 1149 * no race conditions occur from this. 1150 */ 1151 do { 1152 error = flushbuflist(&bo->bo_clean, 1153 flags, bo, slpflag, slptimeo); 1154 if (error == 0) 1155 error = flushbuflist(&bo->bo_dirty, 1156 flags, bo, slpflag, slptimeo); 1157 if (error != 0 && error != EAGAIN) { 1158 BO_UNLOCK(bo); 1159 return (error); 1160 } 1161 } while (error != 0); 1162 1163 /* 1164 * Wait for I/O to complete. XXX needs cleaning up. The vnode can 1165 * have write I/O in-progress but if there is a VM object then the 1166 * VM object can also have read-I/O in-progress. 1167 */ 1168 do { 1169 bufobj_wwait(bo, 0, 0); 1170 BO_UNLOCK(bo); 1171 if (bo->bo_object != NULL) { 1172 VM_OBJECT_LOCK(bo->bo_object); 1173 vm_object_pip_wait(bo->bo_object, "bovlbx"); 1174 VM_OBJECT_UNLOCK(bo->bo_object); 1175 } 1176 BO_LOCK(bo); 1177 } while (bo->bo_numoutput > 0); 1178 BO_UNLOCK(bo); 1179 1180 /* 1181 * Destroy the copy in the VM cache, too. 1182 */ 1183 if (bo->bo_object != NULL && (flags & (V_ALT | V_NORMAL)) == 0) { 1184 VM_OBJECT_LOCK(bo->bo_object); 1185 vm_object_page_remove(bo->bo_object, 0, 0, 1186 (flags & V_SAVE) ? TRUE : FALSE); 1187 VM_OBJECT_UNLOCK(bo->bo_object); 1188 } 1189 1190 #ifdef INVARIANTS 1191 BO_LOCK(bo); 1192 if ((flags & (V_ALT | V_NORMAL)) == 0 && 1193 (bo->bo_dirty.bv_cnt > 0 || bo->bo_clean.bv_cnt > 0)) 1194 panic("vinvalbuf: flush failed"); 1195 BO_UNLOCK(bo); 1196 #endif 1197 return (0); 1198 } 1199 1200 /* 1201 * Flush out and invalidate all buffers associated with a vnode. 1202 * Called with the underlying object locked. 1203 */ 1204 int 1205 vinvalbuf(struct vnode *vp, int flags, int slpflag, int slptimeo) 1206 { 1207 1208 CTR3(KTR_VFS, "%s: vp %p with flags %d", __func__, vp, flags); 1209 ASSERT_VOP_LOCKED(vp, "vinvalbuf"); 1210 return (bufobj_invalbuf(&vp->v_bufobj, flags, slpflag, slptimeo)); 1211 } 1212 1213 /* 1214 * Flush out buffers on the specified list. 1215 * 1216 */ 1217 static int 1218 flushbuflist( struct bufv *bufv, int flags, struct bufobj *bo, int slpflag, 1219 int slptimeo) 1220 { 1221 struct buf *bp, *nbp; 1222 int retval, error; 1223 daddr_t lblkno; 1224 b_xflags_t xflags; 1225 1226 ASSERT_BO_LOCKED(bo); 1227 1228 retval = 0; 1229 TAILQ_FOREACH_SAFE(bp, &bufv->bv_hd, b_bobufs, nbp) { 1230 if (((flags & V_NORMAL) && (bp->b_xflags & BX_ALTDATA)) || 1231 ((flags & V_ALT) && (bp->b_xflags & BX_ALTDATA) == 0)) { 1232 continue; 1233 } 1234 lblkno = 0; 1235 xflags = 0; 1236 if (nbp != NULL) { 1237 lblkno = nbp->b_lblkno; 1238 xflags = nbp->b_xflags & 1239 (BX_BKGRDMARKER | BX_VNDIRTY | BX_VNCLEAN); 1240 } 1241 retval = EAGAIN; 1242 error = BUF_TIMELOCK(bp, 1243 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, BO_MTX(bo), 1244 "flushbuf", slpflag, slptimeo); 1245 if (error) { 1246 BO_LOCK(bo); 1247 return (error != ENOLCK ? error : EAGAIN); 1248 } 1249 KASSERT(bp->b_bufobj == bo, 1250 ("bp %p wrong b_bufobj %p should be %p", 1251 bp, bp->b_bufobj, bo)); 1252 if (bp->b_bufobj != bo) { /* XXX: necessary ? */ 1253 BUF_UNLOCK(bp); 1254 BO_LOCK(bo); 1255 return (EAGAIN); 1256 } 1257 /* 1258 * XXX Since there are no node locks for NFS, I 1259 * believe there is a slight chance that a delayed 1260 * write will occur while sleeping just above, so 1261 * check for it. 1262 */ 1263 if (((bp->b_flags & (B_DELWRI | B_INVAL)) == B_DELWRI) && 1264 (flags & V_SAVE)) { 1265 bremfree(bp); 1266 bp->b_flags |= B_ASYNC; 1267 bwrite(bp); 1268 BO_LOCK(bo); 1269 return (EAGAIN); /* XXX: why not loop ? */ 1270 } 1271 bremfree(bp); 1272 bp->b_flags |= (B_INVAL | B_RELBUF); 1273 bp->b_flags &= ~B_ASYNC; 1274 brelse(bp); 1275 BO_LOCK(bo); 1276 if (nbp != NULL && 1277 (nbp->b_bufobj != bo || 1278 nbp->b_lblkno != lblkno || 1279 (nbp->b_xflags & 1280 (BX_BKGRDMARKER | BX_VNDIRTY | BX_VNCLEAN)) != xflags)) 1281 break; /* nbp invalid */ 1282 } 1283 return (retval); 1284 } 1285 1286 /* 1287 * Truncate a file's buffer and pages to a specified length. This 1288 * is in lieu of the old vinvalbuf mechanism, which performed unneeded 1289 * sync activity. 1290 */ 1291 int 1292 vtruncbuf(struct vnode *vp, struct ucred *cred, struct thread *td, 1293 off_t length, int blksize) 1294 { 1295 struct buf *bp, *nbp; 1296 int anyfreed; 1297 int trunclbn; 1298 struct bufobj *bo; 1299 1300 CTR5(KTR_VFS, "%s: vp %p with cred %p and block %d:%ju", __func__, 1301 vp, cred, blksize, (uintmax_t)length); 1302 1303 /* 1304 * Round up to the *next* lbn. 1305 */ 1306 trunclbn = (length + blksize - 1) / blksize; 1307 1308 ASSERT_VOP_LOCKED(vp, "vtruncbuf"); 1309 restart: 1310 bo = &vp->v_bufobj; 1311 BO_LOCK(bo); 1312 anyfreed = 1; 1313 for (;anyfreed;) { 1314 anyfreed = 0; 1315 TAILQ_FOREACH_SAFE(bp, &bo->bo_clean.bv_hd, b_bobufs, nbp) { 1316 if (bp->b_lblkno < trunclbn) 1317 continue; 1318 if (BUF_LOCK(bp, 1319 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, 1320 BO_MTX(bo)) == ENOLCK) 1321 goto restart; 1322 1323 bremfree(bp); 1324 bp->b_flags |= (B_INVAL | B_RELBUF); 1325 bp->b_flags &= ~B_ASYNC; 1326 brelse(bp); 1327 anyfreed = 1; 1328 1329 if (nbp != NULL && 1330 (((nbp->b_xflags & BX_VNCLEAN) == 0) || 1331 (nbp->b_vp != vp) || 1332 (nbp->b_flags & B_DELWRI))) { 1333 goto restart; 1334 } 1335 BO_LOCK(bo); 1336 } 1337 1338 TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) { 1339 if (bp->b_lblkno < trunclbn) 1340 continue; 1341 if (BUF_LOCK(bp, 1342 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, 1343 BO_MTX(bo)) == ENOLCK) 1344 goto restart; 1345 bremfree(bp); 1346 bp->b_flags |= (B_INVAL | B_RELBUF); 1347 bp->b_flags &= ~B_ASYNC; 1348 brelse(bp); 1349 anyfreed = 1; 1350 if (nbp != NULL && 1351 (((nbp->b_xflags & BX_VNDIRTY) == 0) || 1352 (nbp->b_vp != vp) || 1353 (nbp->b_flags & B_DELWRI) == 0)) { 1354 goto restart; 1355 } 1356 BO_LOCK(bo); 1357 } 1358 } 1359 1360 if (length > 0) { 1361 restartsync: 1362 TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) { 1363 if (bp->b_lblkno > 0) 1364 continue; 1365 /* 1366 * Since we hold the vnode lock this should only 1367 * fail if we're racing with the buf daemon. 1368 */ 1369 if (BUF_LOCK(bp, 1370 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, 1371 BO_MTX(bo)) == ENOLCK) { 1372 goto restart; 1373 } 1374 VNASSERT((bp->b_flags & B_DELWRI), vp, 1375 ("buf(%p) on dirty queue without DELWRI", bp)); 1376 1377 bremfree(bp); 1378 bawrite(bp); 1379 BO_LOCK(bo); 1380 goto restartsync; 1381 } 1382 } 1383 1384 bufobj_wwait(bo, 0, 0); 1385 BO_UNLOCK(bo); 1386 vnode_pager_setsize(vp, length); 1387 1388 return (0); 1389 } 1390 1391 /* 1392 * buf_splay() - splay tree core for the clean/dirty list of buffers in 1393 * a vnode. 1394 * 1395 * NOTE: We have to deal with the special case of a background bitmap 1396 * buffer, a situation where two buffers will have the same logical 1397 * block offset. We want (1) only the foreground buffer to be accessed 1398 * in a lookup and (2) must differentiate between the foreground and 1399 * background buffer in the splay tree algorithm because the splay 1400 * tree cannot normally handle multiple entities with the same 'index'. 1401 * We accomplish this by adding differentiating flags to the splay tree's 1402 * numerical domain. 1403 */ 1404 static 1405 struct buf * 1406 buf_splay(daddr_t lblkno, b_xflags_t xflags, struct buf *root) 1407 { 1408 struct buf dummy; 1409 struct buf *lefttreemax, *righttreemin, *y; 1410 1411 if (root == NULL) 1412 return (NULL); 1413 lefttreemax = righttreemin = &dummy; 1414 for (;;) { 1415 if (lblkno < root->b_lblkno || 1416 (lblkno == root->b_lblkno && 1417 (xflags & BX_BKGRDMARKER) < (root->b_xflags & BX_BKGRDMARKER))) { 1418 if ((y = root->b_left) == NULL) 1419 break; 1420 if (lblkno < y->b_lblkno) { 1421 /* Rotate right. */ 1422 root->b_left = y->b_right; 1423 y->b_right = root; 1424 root = y; 1425 if ((y = root->b_left) == NULL) 1426 break; 1427 } 1428 /* Link into the new root's right tree. */ 1429 righttreemin->b_left = root; 1430 righttreemin = root; 1431 } else if (lblkno > root->b_lblkno || 1432 (lblkno == root->b_lblkno && 1433 (xflags & BX_BKGRDMARKER) > (root->b_xflags & BX_BKGRDMARKER))) { 1434 if ((y = root->b_right) == NULL) 1435 break; 1436 if (lblkno > y->b_lblkno) { 1437 /* Rotate left. */ 1438 root->b_right = y->b_left; 1439 y->b_left = root; 1440 root = y; 1441 if ((y = root->b_right) == NULL) 1442 break; 1443 } 1444 /* Link into the new root's left tree. */ 1445 lefttreemax->b_right = root; 1446 lefttreemax = root; 1447 } else { 1448 break; 1449 } 1450 root = y; 1451 } 1452 /* Assemble the new root. */ 1453 lefttreemax->b_right = root->b_left; 1454 righttreemin->b_left = root->b_right; 1455 root->b_left = dummy.b_right; 1456 root->b_right = dummy.b_left; 1457 return (root); 1458 } 1459 1460 static void 1461 buf_vlist_remove(struct buf *bp) 1462 { 1463 struct buf *root; 1464 struct bufv *bv; 1465 1466 KASSERT(bp->b_bufobj != NULL, ("No b_bufobj %p", bp)); 1467 ASSERT_BO_LOCKED(bp->b_bufobj); 1468 KASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) != 1469 (BX_VNDIRTY|BX_VNCLEAN), 1470 ("buf_vlist_remove: Buf %p is on two lists", bp)); 1471 if (bp->b_xflags & BX_VNDIRTY) 1472 bv = &bp->b_bufobj->bo_dirty; 1473 else 1474 bv = &bp->b_bufobj->bo_clean; 1475 if (bp != bv->bv_root) { 1476 root = buf_splay(bp->b_lblkno, bp->b_xflags, bv->bv_root); 1477 KASSERT(root == bp, ("splay lookup failed in remove")); 1478 } 1479 if (bp->b_left == NULL) { 1480 root = bp->b_right; 1481 } else { 1482 root = buf_splay(bp->b_lblkno, bp->b_xflags, bp->b_left); 1483 root->b_right = bp->b_right; 1484 } 1485 bv->bv_root = root; 1486 TAILQ_REMOVE(&bv->bv_hd, bp, b_bobufs); 1487 bv->bv_cnt--; 1488 bp->b_xflags &= ~(BX_VNDIRTY | BX_VNCLEAN); 1489 } 1490 1491 /* 1492 * Add the buffer to the sorted clean or dirty block list using a 1493 * splay tree algorithm. 1494 * 1495 * NOTE: xflags is passed as a constant, optimizing this inline function! 1496 */ 1497 static void 1498 buf_vlist_add(struct buf *bp, struct bufobj *bo, b_xflags_t xflags) 1499 { 1500 struct buf *root; 1501 struct bufv *bv; 1502 1503 ASSERT_BO_LOCKED(bo); 1504 KASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) == 0, 1505 ("buf_vlist_add: Buf %p has existing xflags %d", bp, bp->b_xflags)); 1506 bp->b_xflags |= xflags; 1507 if (xflags & BX_VNDIRTY) 1508 bv = &bo->bo_dirty; 1509 else 1510 bv = &bo->bo_clean; 1511 1512 root = buf_splay(bp->b_lblkno, bp->b_xflags, bv->bv_root); 1513 if (root == NULL) { 1514 bp->b_left = NULL; 1515 bp->b_right = NULL; 1516 TAILQ_INSERT_TAIL(&bv->bv_hd, bp, b_bobufs); 1517 } else if (bp->b_lblkno < root->b_lblkno || 1518 (bp->b_lblkno == root->b_lblkno && 1519 (bp->b_xflags & BX_BKGRDMARKER) < (root->b_xflags & BX_BKGRDMARKER))) { 1520 bp->b_left = root->b_left; 1521 bp->b_right = root; 1522 root->b_left = NULL; 1523 TAILQ_INSERT_BEFORE(root, bp, b_bobufs); 1524 } else { 1525 bp->b_right = root->b_right; 1526 bp->b_left = root; 1527 root->b_right = NULL; 1528 TAILQ_INSERT_AFTER(&bv->bv_hd, root, bp, b_bobufs); 1529 } 1530 bv->bv_cnt++; 1531 bv->bv_root = bp; 1532 } 1533 1534 /* 1535 * Lookup a buffer using the splay tree. Note that we specifically avoid 1536 * shadow buffers used in background bitmap writes. 1537 * 1538 * This code isn't quite efficient as it could be because we are maintaining 1539 * two sorted lists and do not know which list the block resides in. 1540 * 1541 * During a "make buildworld" the desired buffer is found at one of 1542 * the roots more than 60% of the time. Thus, checking both roots 1543 * before performing either splay eliminates unnecessary splays on the 1544 * first tree splayed. 1545 */ 1546 struct buf * 1547 gbincore(struct bufobj *bo, daddr_t lblkno) 1548 { 1549 struct buf *bp; 1550 1551 ASSERT_BO_LOCKED(bo); 1552 if ((bp = bo->bo_clean.bv_root) != NULL && 1553 bp->b_lblkno == lblkno && !(bp->b_xflags & BX_BKGRDMARKER)) 1554 return (bp); 1555 if ((bp = bo->bo_dirty.bv_root) != NULL && 1556 bp->b_lblkno == lblkno && !(bp->b_xflags & BX_BKGRDMARKER)) 1557 return (bp); 1558 if ((bp = bo->bo_clean.bv_root) != NULL) { 1559 bo->bo_clean.bv_root = bp = buf_splay(lblkno, 0, bp); 1560 if (bp->b_lblkno == lblkno && !(bp->b_xflags & BX_BKGRDMARKER)) 1561 return (bp); 1562 } 1563 if ((bp = bo->bo_dirty.bv_root) != NULL) { 1564 bo->bo_dirty.bv_root = bp = buf_splay(lblkno, 0, bp); 1565 if (bp->b_lblkno == lblkno && !(bp->b_xflags & BX_BKGRDMARKER)) 1566 return (bp); 1567 } 1568 return (NULL); 1569 } 1570 1571 /* 1572 * Associate a buffer with a vnode. 1573 */ 1574 void 1575 bgetvp(struct vnode *vp, struct buf *bp) 1576 { 1577 struct bufobj *bo; 1578 1579 bo = &vp->v_bufobj; 1580 ASSERT_BO_LOCKED(bo); 1581 VNASSERT(bp->b_vp == NULL, bp->b_vp, ("bgetvp: not free")); 1582 1583 CTR3(KTR_BUF, "bgetvp(%p) vp %p flags %X", bp, vp, bp->b_flags); 1584 VNASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) == 0, vp, 1585 ("bgetvp: bp already attached! %p", bp)); 1586 1587 vhold(vp); 1588 if (VFS_NEEDSGIANT(vp->v_mount) || bo->bo_flag & BO_NEEDSGIANT) 1589 bp->b_flags |= B_NEEDSGIANT; 1590 bp->b_vp = vp; 1591 bp->b_bufobj = bo; 1592 /* 1593 * Insert onto list for new vnode. 1594 */ 1595 buf_vlist_add(bp, bo, BX_VNCLEAN); 1596 } 1597 1598 /* 1599 * Disassociate a buffer from a vnode. 1600 */ 1601 void 1602 brelvp(struct buf *bp) 1603 { 1604 struct bufobj *bo; 1605 struct vnode *vp; 1606 1607 CTR3(KTR_BUF, "brelvp(%p) vp %p flags %X", bp, bp->b_vp, bp->b_flags); 1608 KASSERT(bp->b_vp != NULL, ("brelvp: NULL")); 1609 1610 /* 1611 * Delete from old vnode list, if on one. 1612 */ 1613 vp = bp->b_vp; /* XXX */ 1614 bo = bp->b_bufobj; 1615 BO_LOCK(bo); 1616 if (bp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN)) 1617 buf_vlist_remove(bp); 1618 else 1619 panic("brelvp: Buffer %p not on queue.", bp); 1620 if ((bo->bo_flag & BO_ONWORKLST) && bo->bo_dirty.bv_cnt == 0) { 1621 bo->bo_flag &= ~BO_ONWORKLST; 1622 mtx_lock(&sync_mtx); 1623 LIST_REMOVE(bo, bo_synclist); 1624 syncer_worklist_len--; 1625 mtx_unlock(&sync_mtx); 1626 } 1627 bp->b_flags &= ~B_NEEDSGIANT; 1628 bp->b_vp = NULL; 1629 bp->b_bufobj = NULL; 1630 BO_UNLOCK(bo); 1631 vdrop(vp); 1632 } 1633 1634 /* 1635 * Add an item to the syncer work queue. 1636 */ 1637 static void 1638 vn_syncer_add_to_worklist(struct bufobj *bo, int delay) 1639 { 1640 int queue, slot; 1641 1642 ASSERT_BO_LOCKED(bo); 1643 1644 mtx_lock(&sync_mtx); 1645 if (bo->bo_flag & BO_ONWORKLST) 1646 LIST_REMOVE(bo, bo_synclist); 1647 else { 1648 bo->bo_flag |= BO_ONWORKLST; 1649 syncer_worklist_len++; 1650 } 1651 1652 if (delay > syncer_maxdelay - 2) 1653 delay = syncer_maxdelay - 2; 1654 slot = (syncer_delayno + delay) & syncer_mask; 1655 1656 queue = VFS_NEEDSGIANT(bo->__bo_vnode->v_mount) ? WI_GIANTQ : 1657 WI_MPSAFEQ; 1658 LIST_INSERT_HEAD(&syncer_workitem_pending[queue][slot], bo, 1659 bo_synclist); 1660 mtx_unlock(&sync_mtx); 1661 } 1662 1663 static int 1664 sysctl_vfs_worklist_len(SYSCTL_HANDLER_ARGS) 1665 { 1666 int error, len; 1667 1668 mtx_lock(&sync_mtx); 1669 len = syncer_worklist_len - sync_vnode_count; 1670 mtx_unlock(&sync_mtx); 1671 error = SYSCTL_OUT(req, &len, sizeof(len)); 1672 return (error); 1673 } 1674 1675 SYSCTL_PROC(_vfs, OID_AUTO, worklist_len, CTLTYPE_INT | CTLFLAG_RD, NULL, 0, 1676 sysctl_vfs_worklist_len, "I", "Syncer thread worklist length"); 1677 1678 static struct proc *updateproc; 1679 static void sched_sync(void); 1680 static struct kproc_desc up_kp = { 1681 "syncer", 1682 sched_sync, 1683 &updateproc 1684 }; 1685 SYSINIT(syncer, SI_SUB_KTHREAD_UPDATE, SI_ORDER_FIRST, kproc_start, &up_kp); 1686 1687 static int 1688 sync_vnode(struct synclist *slp, struct bufobj **bo, struct thread *td) 1689 { 1690 struct vnode *vp; 1691 struct mount *mp; 1692 1693 *bo = LIST_FIRST(slp); 1694 if (*bo == NULL) 1695 return (0); 1696 vp = (*bo)->__bo_vnode; /* XXX */ 1697 if (VOP_ISLOCKED(vp) != 0 || VI_TRYLOCK(vp) == 0) 1698 return (1); 1699 /* 1700 * We use vhold in case the vnode does not 1701 * successfully sync. vhold prevents the vnode from 1702 * going away when we unlock the sync_mtx so that 1703 * we can acquire the vnode interlock. 1704 */ 1705 vholdl(vp); 1706 mtx_unlock(&sync_mtx); 1707 VI_UNLOCK(vp); 1708 if (vn_start_write(vp, &mp, V_NOWAIT) != 0) { 1709 vdrop(vp); 1710 mtx_lock(&sync_mtx); 1711 return (*bo == LIST_FIRST(slp)); 1712 } 1713 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 1714 (void) VOP_FSYNC(vp, MNT_LAZY, td); 1715 VOP_UNLOCK(vp, 0); 1716 vn_finished_write(mp); 1717 BO_LOCK(*bo); 1718 if (((*bo)->bo_flag & BO_ONWORKLST) != 0) { 1719 /* 1720 * Put us back on the worklist. The worklist 1721 * routine will remove us from our current 1722 * position and then add us back in at a later 1723 * position. 1724 */ 1725 vn_syncer_add_to_worklist(*bo, syncdelay); 1726 } 1727 BO_UNLOCK(*bo); 1728 vdrop(vp); 1729 mtx_lock(&sync_mtx); 1730 return (0); 1731 } 1732 1733 /* 1734 * System filesystem synchronizer daemon. 1735 */ 1736 static void 1737 sched_sync(void) 1738 { 1739 struct synclist *gnext, *next; 1740 struct synclist *gslp, *slp; 1741 struct bufobj *bo; 1742 long starttime; 1743 struct thread *td = curthread; 1744 int last_work_seen; 1745 int net_worklist_len; 1746 int syncer_final_iter; 1747 int first_printf; 1748 int error; 1749 1750 last_work_seen = 0; 1751 syncer_final_iter = 0; 1752 first_printf = 1; 1753 syncer_state = SYNCER_RUNNING; 1754 starttime = time_uptime; 1755 td->td_pflags |= TDP_NORUNNINGBUF; 1756 1757 EVENTHANDLER_REGISTER(shutdown_pre_sync, syncer_shutdown, td->td_proc, 1758 SHUTDOWN_PRI_LAST); 1759 1760 mtx_lock(&sync_mtx); 1761 for (;;) { 1762 if (syncer_state == SYNCER_FINAL_DELAY && 1763 syncer_final_iter == 0) { 1764 mtx_unlock(&sync_mtx); 1765 kproc_suspend_check(td->td_proc); 1766 mtx_lock(&sync_mtx); 1767 } 1768 net_worklist_len = syncer_worklist_len - sync_vnode_count; 1769 if (syncer_state != SYNCER_RUNNING && 1770 starttime != time_uptime) { 1771 if (first_printf) { 1772 printf("\nSyncing disks, vnodes remaining..."); 1773 first_printf = 0; 1774 } 1775 printf("%d ", net_worklist_len); 1776 } 1777 starttime = time_uptime; 1778 1779 /* 1780 * Push files whose dirty time has expired. Be careful 1781 * of interrupt race on slp queue. 1782 * 1783 * Skip over empty worklist slots when shutting down. 1784 */ 1785 do { 1786 slp = &syncer_workitem_pending[WI_MPSAFEQ][syncer_delayno]; 1787 gslp = &syncer_workitem_pending[WI_GIANTQ][syncer_delayno]; 1788 syncer_delayno += 1; 1789 if (syncer_delayno == syncer_maxdelay) 1790 syncer_delayno = 0; 1791 next = &syncer_workitem_pending[WI_MPSAFEQ][syncer_delayno]; 1792 gnext = &syncer_workitem_pending[WI_GIANTQ][syncer_delayno]; 1793 /* 1794 * If the worklist has wrapped since the 1795 * it was emptied of all but syncer vnodes, 1796 * switch to the FINAL_DELAY state and run 1797 * for one more second. 1798 */ 1799 if (syncer_state == SYNCER_SHUTTING_DOWN && 1800 net_worklist_len == 0 && 1801 last_work_seen == syncer_delayno) { 1802 syncer_state = SYNCER_FINAL_DELAY; 1803 syncer_final_iter = SYNCER_SHUTDOWN_SPEEDUP; 1804 } 1805 } while (syncer_state != SYNCER_RUNNING && LIST_EMPTY(slp) && 1806 LIST_EMPTY(gslp) && syncer_worklist_len > 0); 1807 1808 /* 1809 * Keep track of the last time there was anything 1810 * on the worklist other than syncer vnodes. 1811 * Return to the SHUTTING_DOWN state if any 1812 * new work appears. 1813 */ 1814 if (net_worklist_len > 0 || syncer_state == SYNCER_RUNNING) 1815 last_work_seen = syncer_delayno; 1816 if (net_worklist_len > 0 && syncer_state == SYNCER_FINAL_DELAY) 1817 syncer_state = SYNCER_SHUTTING_DOWN; 1818 while (!LIST_EMPTY(slp)) { 1819 error = sync_vnode(slp, &bo, td); 1820 if (error == 1) { 1821 LIST_REMOVE(bo, bo_synclist); 1822 LIST_INSERT_HEAD(next, bo, bo_synclist); 1823 continue; 1824 } 1825 } 1826 if (!LIST_EMPTY(gslp)) { 1827 mtx_unlock(&sync_mtx); 1828 mtx_lock(&Giant); 1829 mtx_lock(&sync_mtx); 1830 while (!LIST_EMPTY(gslp)) { 1831 error = sync_vnode(gslp, &bo, td); 1832 if (error == 1) { 1833 LIST_REMOVE(bo, bo_synclist); 1834 LIST_INSERT_HEAD(gnext, bo, 1835 bo_synclist); 1836 continue; 1837 } 1838 } 1839 mtx_unlock(&Giant); 1840 } 1841 if (syncer_state == SYNCER_FINAL_DELAY && syncer_final_iter > 0) 1842 syncer_final_iter--; 1843 /* 1844 * The variable rushjob allows the kernel to speed up the 1845 * processing of the filesystem syncer process. A rushjob 1846 * value of N tells the filesystem syncer to process the next 1847 * N seconds worth of work on its queue ASAP. Currently rushjob 1848 * is used by the soft update code to speed up the filesystem 1849 * syncer process when the incore state is getting so far 1850 * ahead of the disk that the kernel memory pool is being 1851 * threatened with exhaustion. 1852 */ 1853 if (rushjob > 0) { 1854 rushjob -= 1; 1855 continue; 1856 } 1857 /* 1858 * Just sleep for a short period of time between 1859 * iterations when shutting down to allow some I/O 1860 * to happen. 1861 * 1862 * If it has taken us less than a second to process the 1863 * current work, then wait. Otherwise start right over 1864 * again. We can still lose time if any single round 1865 * takes more than two seconds, but it does not really 1866 * matter as we are just trying to generally pace the 1867 * filesystem activity. 1868 */ 1869 if (syncer_state != SYNCER_RUNNING) 1870 cv_timedwait(&sync_wakeup, &sync_mtx, 1871 hz / SYNCER_SHUTDOWN_SPEEDUP); 1872 else if (time_uptime == starttime) 1873 cv_timedwait(&sync_wakeup, &sync_mtx, hz); 1874 } 1875 } 1876 1877 /* 1878 * Request the syncer daemon to speed up its work. 1879 * We never push it to speed up more than half of its 1880 * normal turn time, otherwise it could take over the cpu. 1881 */ 1882 int 1883 speedup_syncer(void) 1884 { 1885 int ret = 0; 1886 1887 mtx_lock(&sync_mtx); 1888 if (rushjob < syncdelay / 2) { 1889 rushjob += 1; 1890 stat_rush_requests += 1; 1891 ret = 1; 1892 } 1893 mtx_unlock(&sync_mtx); 1894 cv_broadcast(&sync_wakeup); 1895 return (ret); 1896 } 1897 1898 /* 1899 * Tell the syncer to speed up its work and run though its work 1900 * list several times, then tell it to shut down. 1901 */ 1902 static void 1903 syncer_shutdown(void *arg, int howto) 1904 { 1905 1906 if (howto & RB_NOSYNC) 1907 return; 1908 mtx_lock(&sync_mtx); 1909 syncer_state = SYNCER_SHUTTING_DOWN; 1910 rushjob = 0; 1911 mtx_unlock(&sync_mtx); 1912 cv_broadcast(&sync_wakeup); 1913 kproc_shutdown(arg, howto); 1914 } 1915 1916 /* 1917 * Reassign a buffer from one vnode to another. 1918 * Used to assign file specific control information 1919 * (indirect blocks) to the vnode to which they belong. 1920 */ 1921 void 1922 reassignbuf(struct buf *bp) 1923 { 1924 struct vnode *vp; 1925 struct bufobj *bo; 1926 int delay; 1927 #ifdef INVARIANTS 1928 struct bufv *bv; 1929 #endif 1930 1931 vp = bp->b_vp; 1932 bo = bp->b_bufobj; 1933 ++reassignbufcalls; 1934 1935 CTR3(KTR_BUF, "reassignbuf(%p) vp %p flags %X", 1936 bp, bp->b_vp, bp->b_flags); 1937 /* 1938 * B_PAGING flagged buffers cannot be reassigned because their vp 1939 * is not fully linked in. 1940 */ 1941 if (bp->b_flags & B_PAGING) 1942 panic("cannot reassign paging buffer"); 1943 1944 /* 1945 * Delete from old vnode list, if on one. 1946 */ 1947 BO_LOCK(bo); 1948 if (bp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN)) 1949 buf_vlist_remove(bp); 1950 else 1951 panic("reassignbuf: Buffer %p not on queue.", bp); 1952 /* 1953 * If dirty, put on list of dirty buffers; otherwise insert onto list 1954 * of clean buffers. 1955 */ 1956 if (bp->b_flags & B_DELWRI) { 1957 if ((bo->bo_flag & BO_ONWORKLST) == 0) { 1958 switch (vp->v_type) { 1959 case VDIR: 1960 delay = dirdelay; 1961 break; 1962 case VCHR: 1963 delay = metadelay; 1964 break; 1965 default: 1966 delay = filedelay; 1967 } 1968 vn_syncer_add_to_worklist(bo, delay); 1969 } 1970 buf_vlist_add(bp, bo, BX_VNDIRTY); 1971 } else { 1972 buf_vlist_add(bp, bo, BX_VNCLEAN); 1973 1974 if ((bo->bo_flag & BO_ONWORKLST) && bo->bo_dirty.bv_cnt == 0) { 1975 mtx_lock(&sync_mtx); 1976 LIST_REMOVE(bo, bo_synclist); 1977 syncer_worklist_len--; 1978 mtx_unlock(&sync_mtx); 1979 bo->bo_flag &= ~BO_ONWORKLST; 1980 } 1981 } 1982 #ifdef INVARIANTS 1983 bv = &bo->bo_clean; 1984 bp = TAILQ_FIRST(&bv->bv_hd); 1985 KASSERT(bp == NULL || bp->b_bufobj == bo, 1986 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 1987 bp = TAILQ_LAST(&bv->bv_hd, buflists); 1988 KASSERT(bp == NULL || bp->b_bufobj == bo, 1989 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 1990 bv = &bo->bo_dirty; 1991 bp = TAILQ_FIRST(&bv->bv_hd); 1992 KASSERT(bp == NULL || bp->b_bufobj == bo, 1993 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 1994 bp = TAILQ_LAST(&bv->bv_hd, buflists); 1995 KASSERT(bp == NULL || bp->b_bufobj == bo, 1996 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 1997 #endif 1998 BO_UNLOCK(bo); 1999 } 2000 2001 /* 2002 * Increment the use and hold counts on the vnode, taking care to reference 2003 * the driver's usecount if this is a chardev. The vholdl() will remove 2004 * the vnode from the free list if it is presently free. Requires the 2005 * vnode interlock and returns with it held. 2006 */ 2007 static void 2008 v_incr_usecount(struct vnode *vp) 2009 { 2010 2011 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2012 vp->v_usecount++; 2013 if (vp->v_type == VCHR && vp->v_rdev != NULL) { 2014 dev_lock(); 2015 vp->v_rdev->si_usecount++; 2016 dev_unlock(); 2017 } 2018 vholdl(vp); 2019 } 2020 2021 /* 2022 * Turn a holdcnt into a use+holdcnt such that only one call to 2023 * v_decr_usecount is needed. 2024 */ 2025 static void 2026 v_upgrade_usecount(struct vnode *vp) 2027 { 2028 2029 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2030 vp->v_usecount++; 2031 if (vp->v_type == VCHR && vp->v_rdev != NULL) { 2032 dev_lock(); 2033 vp->v_rdev->si_usecount++; 2034 dev_unlock(); 2035 } 2036 } 2037 2038 /* 2039 * Decrement the vnode use and hold count along with the driver's usecount 2040 * if this is a chardev. The vdropl() below releases the vnode interlock 2041 * as it may free the vnode. 2042 */ 2043 static void 2044 v_decr_usecount(struct vnode *vp) 2045 { 2046 2047 ASSERT_VI_LOCKED(vp, __FUNCTION__); 2048 VNASSERT(vp->v_usecount > 0, vp, 2049 ("v_decr_usecount: negative usecount")); 2050 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2051 vp->v_usecount--; 2052 if (vp->v_type == VCHR && vp->v_rdev != NULL) { 2053 dev_lock(); 2054 vp->v_rdev->si_usecount--; 2055 dev_unlock(); 2056 } 2057 vdropl(vp); 2058 } 2059 2060 /* 2061 * Decrement only the use count and driver use count. This is intended to 2062 * be paired with a follow on vdropl() to release the remaining hold count. 2063 * In this way we may vgone() a vnode with a 0 usecount without risk of 2064 * having it end up on a free list because the hold count is kept above 0. 2065 */ 2066 static void 2067 v_decr_useonly(struct vnode *vp) 2068 { 2069 2070 ASSERT_VI_LOCKED(vp, __FUNCTION__); 2071 VNASSERT(vp->v_usecount > 0, vp, 2072 ("v_decr_useonly: negative usecount")); 2073 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2074 vp->v_usecount--; 2075 if (vp->v_type == VCHR && vp->v_rdev != NULL) { 2076 dev_lock(); 2077 vp->v_rdev->si_usecount--; 2078 dev_unlock(); 2079 } 2080 } 2081 2082 /* 2083 * Grab a particular vnode from the free list, increment its 2084 * reference count and lock it. VI_DOOMED is set if the vnode 2085 * is being destroyed. Only callers who specify LK_RETRY will 2086 * see doomed vnodes. If inactive processing was delayed in 2087 * vput try to do it here. 2088 */ 2089 int 2090 vget(struct vnode *vp, int flags, struct thread *td) 2091 { 2092 int error; 2093 2094 error = 0; 2095 VFS_ASSERT_GIANT(vp->v_mount); 2096 VNASSERT((flags & LK_TYPE_MASK) != 0, vp, 2097 ("vget: invalid lock operation")); 2098 CTR3(KTR_VFS, "%s: vp %p with flags %d", __func__, vp, flags); 2099 2100 if ((flags & LK_INTERLOCK) == 0) 2101 VI_LOCK(vp); 2102 vholdl(vp); 2103 if ((error = vn_lock(vp, flags | LK_INTERLOCK)) != 0) { 2104 vdrop(vp); 2105 CTR2(KTR_VFS, "%s: impossible to lock vnode %p", __func__, 2106 vp); 2107 return (error); 2108 } 2109 if (vp->v_iflag & VI_DOOMED && (flags & LK_RETRY) == 0) 2110 panic("vget: vn_lock failed to return ENOENT\n"); 2111 VI_LOCK(vp); 2112 /* Upgrade our holdcnt to a usecount. */ 2113 v_upgrade_usecount(vp); 2114 /* 2115 * We don't guarantee that any particular close will 2116 * trigger inactive processing so just make a best effort 2117 * here at preventing a reference to a removed file. If 2118 * we don't succeed no harm is done. 2119 */ 2120 if (vp->v_iflag & VI_OWEINACT) { 2121 if (VOP_ISLOCKED(vp) == LK_EXCLUSIVE && 2122 (flags & LK_NOWAIT) == 0) 2123 vinactive(vp, td); 2124 vp->v_iflag &= ~VI_OWEINACT; 2125 } 2126 VI_UNLOCK(vp); 2127 return (0); 2128 } 2129 2130 /* 2131 * Increase the reference count of a vnode. 2132 */ 2133 void 2134 vref(struct vnode *vp) 2135 { 2136 2137 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2138 VI_LOCK(vp); 2139 v_incr_usecount(vp); 2140 VI_UNLOCK(vp); 2141 } 2142 2143 /* 2144 * Return reference count of a vnode. 2145 * 2146 * The results of this call are only guaranteed when some mechanism other 2147 * than the VI lock is used to stop other processes from gaining references 2148 * to the vnode. This may be the case if the caller holds the only reference. 2149 * This is also useful when stale data is acceptable as race conditions may 2150 * be accounted for by some other means. 2151 */ 2152 int 2153 vrefcnt(struct vnode *vp) 2154 { 2155 int usecnt; 2156 2157 VI_LOCK(vp); 2158 usecnt = vp->v_usecount; 2159 VI_UNLOCK(vp); 2160 2161 return (usecnt); 2162 } 2163 2164 #define VPUTX_VRELE 1 2165 #define VPUTX_VPUT 2 2166 #define VPUTX_VUNREF 3 2167 2168 static void 2169 vputx(struct vnode *vp, int func) 2170 { 2171 int error; 2172 2173 KASSERT(vp != NULL, ("vputx: null vp")); 2174 if (func == VPUTX_VUNREF) 2175 ASSERT_VOP_ELOCKED(vp, "vunref"); 2176 else if (func == VPUTX_VPUT) 2177 ASSERT_VOP_LOCKED(vp, "vput"); 2178 else 2179 KASSERT(func == VPUTX_VRELE, ("vputx: wrong func")); 2180 VFS_ASSERT_GIANT(vp->v_mount); 2181 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2182 VI_LOCK(vp); 2183 2184 /* Skip this v_writecount check if we're going to panic below. */ 2185 VNASSERT(vp->v_writecount < vp->v_usecount || vp->v_usecount < 1, vp, 2186 ("vputx: missed vn_close")); 2187 error = 0; 2188 2189 if (vp->v_usecount > 1 || ((vp->v_iflag & VI_DOINGINACT) && 2190 vp->v_usecount == 1)) { 2191 if (func == VPUTX_VPUT) 2192 VOP_UNLOCK(vp, 0); 2193 v_decr_usecount(vp); 2194 return; 2195 } 2196 2197 if (vp->v_usecount != 1) { 2198 #ifdef DIAGNOSTIC 2199 vprint("vputx: negative ref count", vp); 2200 #endif 2201 panic("vputx: negative ref cnt"); 2202 } 2203 CTR2(KTR_VFS, "%s: return vnode %p to the freelist", __func__, vp); 2204 /* 2205 * We want to hold the vnode until the inactive finishes to 2206 * prevent vgone() races. We drop the use count here and the 2207 * hold count below when we're done. 2208 */ 2209 v_decr_useonly(vp); 2210 /* 2211 * We must call VOP_INACTIVE with the node locked. Mark 2212 * as VI_DOINGINACT to avoid recursion. 2213 */ 2214 vp->v_iflag |= VI_OWEINACT; 2215 if (func == VPUTX_VRELE) { 2216 error = vn_lock(vp, LK_EXCLUSIVE | LK_INTERLOCK); 2217 VI_LOCK(vp); 2218 } else if (func == VPUTX_VPUT && VOP_ISLOCKED(vp) != LK_EXCLUSIVE) { 2219 error = VOP_LOCK(vp, LK_UPGRADE | LK_INTERLOCK | LK_NOWAIT); 2220 VI_LOCK(vp); 2221 } 2222 if (vp->v_usecount > 0) 2223 vp->v_iflag &= ~VI_OWEINACT; 2224 if (error == 0) { 2225 if (vp->v_iflag & VI_OWEINACT) 2226 vinactive(vp, curthread); 2227 if (func != VPUTX_VUNREF) 2228 VOP_UNLOCK(vp, 0); 2229 } 2230 vdropl(vp); 2231 } 2232 2233 /* 2234 * Vnode put/release. 2235 * If count drops to zero, call inactive routine and return to freelist. 2236 */ 2237 void 2238 vrele(struct vnode *vp) 2239 { 2240 2241 vputx(vp, VPUTX_VRELE); 2242 } 2243 2244 /* 2245 * Release an already locked vnode. This give the same effects as 2246 * unlock+vrele(), but takes less time and avoids releasing and 2247 * re-aquiring the lock (as vrele() acquires the lock internally.) 2248 */ 2249 void 2250 vput(struct vnode *vp) 2251 { 2252 2253 vputx(vp, VPUTX_VPUT); 2254 } 2255 2256 /* 2257 * Release an exclusively locked vnode. Do not unlock the vnode lock. 2258 */ 2259 void 2260 vunref(struct vnode *vp) 2261 { 2262 2263 vputx(vp, VPUTX_VUNREF); 2264 } 2265 2266 /* 2267 * Somebody doesn't want the vnode recycled. 2268 */ 2269 void 2270 vhold(struct vnode *vp) 2271 { 2272 2273 VI_LOCK(vp); 2274 vholdl(vp); 2275 VI_UNLOCK(vp); 2276 } 2277 2278 void 2279 vholdl(struct vnode *vp) 2280 { 2281 2282 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2283 vp->v_holdcnt++; 2284 if (VSHOULDBUSY(vp)) 2285 vbusy(vp); 2286 } 2287 2288 /* 2289 * Note that there is one less who cares about this vnode. vdrop() is the 2290 * opposite of vhold(). 2291 */ 2292 void 2293 vdrop(struct vnode *vp) 2294 { 2295 2296 VI_LOCK(vp); 2297 vdropl(vp); 2298 } 2299 2300 /* 2301 * Drop the hold count of the vnode. If this is the last reference to 2302 * the vnode we will free it if it has been vgone'd otherwise it is 2303 * placed on the free list. 2304 */ 2305 void 2306 vdropl(struct vnode *vp) 2307 { 2308 2309 ASSERT_VI_LOCKED(vp, "vdropl"); 2310 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2311 if (vp->v_holdcnt <= 0) 2312 panic("vdrop: holdcnt %d", vp->v_holdcnt); 2313 vp->v_holdcnt--; 2314 if (vp->v_holdcnt == 0) { 2315 if (vp->v_iflag & VI_DOOMED) { 2316 CTR2(KTR_VFS, "%s: destroying the vnode %p", __func__, 2317 vp); 2318 vdestroy(vp); 2319 return; 2320 } else 2321 vfree(vp); 2322 } 2323 VI_UNLOCK(vp); 2324 } 2325 2326 /* 2327 * Call VOP_INACTIVE on the vnode and manage the DOINGINACT and OWEINACT 2328 * flags. DOINGINACT prevents us from recursing in calls to vinactive. 2329 * OWEINACT tracks whether a vnode missed a call to inactive due to a 2330 * failed lock upgrade. 2331 */ 2332 static void 2333 vinactive(struct vnode *vp, struct thread *td) 2334 { 2335 2336 ASSERT_VOP_ELOCKED(vp, "vinactive"); 2337 ASSERT_VI_LOCKED(vp, "vinactive"); 2338 VNASSERT((vp->v_iflag & VI_DOINGINACT) == 0, vp, 2339 ("vinactive: recursed on VI_DOINGINACT")); 2340 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2341 vp->v_iflag |= VI_DOINGINACT; 2342 vp->v_iflag &= ~VI_OWEINACT; 2343 VI_UNLOCK(vp); 2344 VOP_INACTIVE(vp, td); 2345 VI_LOCK(vp); 2346 VNASSERT(vp->v_iflag & VI_DOINGINACT, vp, 2347 ("vinactive: lost VI_DOINGINACT")); 2348 vp->v_iflag &= ~VI_DOINGINACT; 2349 } 2350 2351 /* 2352 * Remove any vnodes in the vnode table belonging to mount point mp. 2353 * 2354 * If FORCECLOSE is not specified, there should not be any active ones, 2355 * return error if any are found (nb: this is a user error, not a 2356 * system error). If FORCECLOSE is specified, detach any active vnodes 2357 * that are found. 2358 * 2359 * If WRITECLOSE is set, only flush out regular file vnodes open for 2360 * writing. 2361 * 2362 * SKIPSYSTEM causes any vnodes marked VV_SYSTEM to be skipped. 2363 * 2364 * `rootrefs' specifies the base reference count for the root vnode 2365 * of this filesystem. The root vnode is considered busy if its 2366 * v_usecount exceeds this value. On a successful return, vflush(, td) 2367 * will call vrele() on the root vnode exactly rootrefs times. 2368 * If the SKIPSYSTEM or WRITECLOSE flags are specified, rootrefs must 2369 * be zero. 2370 */ 2371 #ifdef DIAGNOSTIC 2372 static int busyprt = 0; /* print out busy vnodes */ 2373 SYSCTL_INT(_debug, OID_AUTO, busyprt, CTLFLAG_RW, &busyprt, 0, ""); 2374 #endif 2375 2376 int 2377 vflush(struct mount *mp, int rootrefs, int flags, struct thread *td) 2378 { 2379 struct vnode *vp, *mvp, *rootvp = NULL; 2380 struct vattr vattr; 2381 int busy = 0, error; 2382 2383 CTR4(KTR_VFS, "%s: mp %p with rootrefs %d and flags %d", __func__, mp, 2384 rootrefs, flags); 2385 if (rootrefs > 0) { 2386 KASSERT((flags & (SKIPSYSTEM | WRITECLOSE)) == 0, 2387 ("vflush: bad args")); 2388 /* 2389 * Get the filesystem root vnode. We can vput() it 2390 * immediately, since with rootrefs > 0, it won't go away. 2391 */ 2392 if ((error = VFS_ROOT(mp, LK_EXCLUSIVE, &rootvp)) != 0) { 2393 CTR2(KTR_VFS, "%s: vfs_root lookup failed with %d", 2394 __func__, error); 2395 return (error); 2396 } 2397 vput(rootvp); 2398 } 2399 MNT_ILOCK(mp); 2400 loop: 2401 MNT_VNODE_FOREACH(vp, mp, mvp) { 2402 VI_LOCK(vp); 2403 vholdl(vp); 2404 MNT_IUNLOCK(mp); 2405 error = vn_lock(vp, LK_INTERLOCK | LK_EXCLUSIVE); 2406 if (error) { 2407 vdrop(vp); 2408 MNT_ILOCK(mp); 2409 MNT_VNODE_FOREACH_ABORT_ILOCKED(mp, mvp); 2410 goto loop; 2411 } 2412 /* 2413 * Skip over a vnodes marked VV_SYSTEM. 2414 */ 2415 if ((flags & SKIPSYSTEM) && (vp->v_vflag & VV_SYSTEM)) { 2416 VOP_UNLOCK(vp, 0); 2417 vdrop(vp); 2418 MNT_ILOCK(mp); 2419 continue; 2420 } 2421 /* 2422 * If WRITECLOSE is set, flush out unlinked but still open 2423 * files (even if open only for reading) and regular file 2424 * vnodes open for writing. 2425 */ 2426 if (flags & WRITECLOSE) { 2427 error = VOP_GETATTR(vp, &vattr, td->td_ucred); 2428 VI_LOCK(vp); 2429 2430 if ((vp->v_type == VNON || 2431 (error == 0 && vattr.va_nlink > 0)) && 2432 (vp->v_writecount == 0 || vp->v_type != VREG)) { 2433 VOP_UNLOCK(vp, 0); 2434 vdropl(vp); 2435 MNT_ILOCK(mp); 2436 continue; 2437 } 2438 } else 2439 VI_LOCK(vp); 2440 /* 2441 * With v_usecount == 0, all we need to do is clear out the 2442 * vnode data structures and we are done. 2443 * 2444 * If FORCECLOSE is set, forcibly close the vnode. 2445 */ 2446 if (vp->v_usecount == 0 || (flags & FORCECLOSE)) { 2447 VNASSERT(vp->v_usecount == 0 || 2448 (vp->v_type != VCHR && vp->v_type != VBLK), vp, 2449 ("device VNODE %p is FORCECLOSED", vp)); 2450 vgonel(vp); 2451 } else { 2452 busy++; 2453 #ifdef DIAGNOSTIC 2454 if (busyprt) 2455 vprint("vflush: busy vnode", vp); 2456 #endif 2457 } 2458 VOP_UNLOCK(vp, 0); 2459 vdropl(vp); 2460 MNT_ILOCK(mp); 2461 } 2462 MNT_IUNLOCK(mp); 2463 if (rootrefs > 0 && (flags & FORCECLOSE) == 0) { 2464 /* 2465 * If just the root vnode is busy, and if its refcount 2466 * is equal to `rootrefs', then go ahead and kill it. 2467 */ 2468 VI_LOCK(rootvp); 2469 KASSERT(busy > 0, ("vflush: not busy")); 2470 VNASSERT(rootvp->v_usecount >= rootrefs, rootvp, 2471 ("vflush: usecount %d < rootrefs %d", 2472 rootvp->v_usecount, rootrefs)); 2473 if (busy == 1 && rootvp->v_usecount == rootrefs) { 2474 VOP_LOCK(rootvp, LK_EXCLUSIVE|LK_INTERLOCK); 2475 vgone(rootvp); 2476 VOP_UNLOCK(rootvp, 0); 2477 busy = 0; 2478 } else 2479 VI_UNLOCK(rootvp); 2480 } 2481 if (busy) { 2482 CTR2(KTR_VFS, "%s: failing as %d vnodes are busy", __func__, 2483 busy); 2484 return (EBUSY); 2485 } 2486 for (; rootrefs > 0; rootrefs--) 2487 vrele(rootvp); 2488 return (0); 2489 } 2490 2491 /* 2492 * Recycle an unused vnode to the front of the free list. 2493 */ 2494 int 2495 vrecycle(struct vnode *vp, struct thread *td) 2496 { 2497 int recycled; 2498 2499 ASSERT_VOP_ELOCKED(vp, "vrecycle"); 2500 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2501 recycled = 0; 2502 VI_LOCK(vp); 2503 if (vp->v_usecount == 0) { 2504 recycled = 1; 2505 vgonel(vp); 2506 } 2507 VI_UNLOCK(vp); 2508 return (recycled); 2509 } 2510 2511 /* 2512 * Eliminate all activity associated with a vnode 2513 * in preparation for reuse. 2514 */ 2515 void 2516 vgone(struct vnode *vp) 2517 { 2518 VI_LOCK(vp); 2519 vgonel(vp); 2520 VI_UNLOCK(vp); 2521 } 2522 2523 /* 2524 * vgone, with the vp interlock held. 2525 */ 2526 void 2527 vgonel(struct vnode *vp) 2528 { 2529 struct thread *td; 2530 int oweinact; 2531 int active; 2532 struct mount *mp; 2533 2534 ASSERT_VOP_ELOCKED(vp, "vgonel"); 2535 ASSERT_VI_LOCKED(vp, "vgonel"); 2536 VNASSERT(vp->v_holdcnt, vp, 2537 ("vgonel: vp %p has no reference.", vp)); 2538 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2539 td = curthread; 2540 2541 /* 2542 * Don't vgonel if we're already doomed. 2543 */ 2544 if (vp->v_iflag & VI_DOOMED) 2545 return; 2546 vp->v_iflag |= VI_DOOMED; 2547 /* 2548 * Check to see if the vnode is in use. If so, we have to call 2549 * VOP_CLOSE() and VOP_INACTIVE(). 2550 */ 2551 active = vp->v_usecount; 2552 oweinact = (vp->v_iflag & VI_OWEINACT); 2553 VI_UNLOCK(vp); 2554 /* 2555 * Clean out any buffers associated with the vnode. 2556 * If the flush fails, just toss the buffers. 2557 */ 2558 mp = NULL; 2559 if (!TAILQ_EMPTY(&vp->v_bufobj.bo_dirty.bv_hd)) 2560 (void) vn_start_secondary_write(vp, &mp, V_WAIT); 2561 if (vinvalbuf(vp, V_SAVE, 0, 0) != 0) 2562 vinvalbuf(vp, 0, 0, 0); 2563 2564 /* 2565 * If purging an active vnode, it must be closed and 2566 * deactivated before being reclaimed. 2567 */ 2568 if (active) 2569 VOP_CLOSE(vp, FNONBLOCK, NOCRED, td); 2570 if (oweinact || active) { 2571 VI_LOCK(vp); 2572 if ((vp->v_iflag & VI_DOINGINACT) == 0) 2573 vinactive(vp, td); 2574 VI_UNLOCK(vp); 2575 } 2576 /* 2577 * Reclaim the vnode. 2578 */ 2579 if (VOP_RECLAIM(vp, td)) 2580 panic("vgone: cannot reclaim"); 2581 if (mp != NULL) 2582 vn_finished_secondary_write(mp); 2583 VNASSERT(vp->v_object == NULL, vp, 2584 ("vop_reclaim left v_object vp=%p, tag=%s", vp, vp->v_tag)); 2585 /* 2586 * Clear the advisory locks and wake up waiting threads. 2587 */ 2588 (void)VOP_ADVLOCKPURGE(vp); 2589 /* 2590 * Delete from old mount point vnode list. 2591 */ 2592 delmntque(vp); 2593 cache_purge(vp); 2594 /* 2595 * Done with purge, reset to the standard lock and invalidate 2596 * the vnode. 2597 */ 2598 VI_LOCK(vp); 2599 vp->v_vnlock = &vp->v_lock; 2600 vp->v_op = &dead_vnodeops; 2601 vp->v_tag = "none"; 2602 vp->v_type = VBAD; 2603 } 2604 2605 /* 2606 * Calculate the total number of references to a special device. 2607 */ 2608 int 2609 vcount(struct vnode *vp) 2610 { 2611 int count; 2612 2613 dev_lock(); 2614 count = vp->v_rdev->si_usecount; 2615 dev_unlock(); 2616 return (count); 2617 } 2618 2619 /* 2620 * Same as above, but using the struct cdev *as argument 2621 */ 2622 int 2623 count_dev(struct cdev *dev) 2624 { 2625 int count; 2626 2627 dev_lock(); 2628 count = dev->si_usecount; 2629 dev_unlock(); 2630 return(count); 2631 } 2632 2633 /* 2634 * Print out a description of a vnode. 2635 */ 2636 static char *typename[] = 2637 {"VNON", "VREG", "VDIR", "VBLK", "VCHR", "VLNK", "VSOCK", "VFIFO", "VBAD", 2638 "VMARKER"}; 2639 2640 void 2641 vn_printf(struct vnode *vp, const char *fmt, ...) 2642 { 2643 va_list ap; 2644 char buf[256], buf2[16]; 2645 u_long flags; 2646 2647 va_start(ap, fmt); 2648 vprintf(fmt, ap); 2649 va_end(ap); 2650 printf("%p: ", (void *)vp); 2651 printf("tag %s, type %s\n", vp->v_tag, typename[vp->v_type]); 2652 printf(" usecount %d, writecount %d, refcount %d mountedhere %p\n", 2653 vp->v_usecount, vp->v_writecount, vp->v_holdcnt, vp->v_mountedhere); 2654 buf[0] = '\0'; 2655 buf[1] = '\0'; 2656 if (vp->v_vflag & VV_ROOT) 2657 strlcat(buf, "|VV_ROOT", sizeof(buf)); 2658 if (vp->v_vflag & VV_ISTTY) 2659 strlcat(buf, "|VV_ISTTY", sizeof(buf)); 2660 if (vp->v_vflag & VV_NOSYNC) 2661 strlcat(buf, "|VV_NOSYNC", sizeof(buf)); 2662 if (vp->v_vflag & VV_CACHEDLABEL) 2663 strlcat(buf, "|VV_CACHEDLABEL", sizeof(buf)); 2664 if (vp->v_vflag & VV_TEXT) 2665 strlcat(buf, "|VV_TEXT", sizeof(buf)); 2666 if (vp->v_vflag & VV_COPYONWRITE) 2667 strlcat(buf, "|VV_COPYONWRITE", sizeof(buf)); 2668 if (vp->v_vflag & VV_SYSTEM) 2669 strlcat(buf, "|VV_SYSTEM", sizeof(buf)); 2670 if (vp->v_vflag & VV_PROCDEP) 2671 strlcat(buf, "|VV_PROCDEP", sizeof(buf)); 2672 if (vp->v_vflag & VV_NOKNOTE) 2673 strlcat(buf, "|VV_NOKNOTE", sizeof(buf)); 2674 if (vp->v_vflag & VV_DELETED) 2675 strlcat(buf, "|VV_DELETED", sizeof(buf)); 2676 if (vp->v_vflag & VV_MD) 2677 strlcat(buf, "|VV_MD", sizeof(buf)); 2678 flags = vp->v_vflag & ~(VV_ROOT | VV_ISTTY | VV_NOSYNC | 2679 VV_CACHEDLABEL | VV_TEXT | VV_COPYONWRITE | VV_SYSTEM | VV_PROCDEP | 2680 VV_NOKNOTE | VV_DELETED | VV_MD); 2681 if (flags != 0) { 2682 snprintf(buf2, sizeof(buf2), "|VV(0x%lx)", flags); 2683 strlcat(buf, buf2, sizeof(buf)); 2684 } 2685 if (vp->v_iflag & VI_MOUNT) 2686 strlcat(buf, "|VI_MOUNT", sizeof(buf)); 2687 if (vp->v_iflag & VI_AGE) 2688 strlcat(buf, "|VI_AGE", sizeof(buf)); 2689 if (vp->v_iflag & VI_DOOMED) 2690 strlcat(buf, "|VI_DOOMED", sizeof(buf)); 2691 if (vp->v_iflag & VI_FREE) 2692 strlcat(buf, "|VI_FREE", sizeof(buf)); 2693 if (vp->v_iflag & VI_DOINGINACT) 2694 strlcat(buf, "|VI_DOINGINACT", sizeof(buf)); 2695 if (vp->v_iflag & VI_OWEINACT) 2696 strlcat(buf, "|VI_OWEINACT", sizeof(buf)); 2697 flags = vp->v_iflag & ~(VI_MOUNT | VI_AGE | VI_DOOMED | VI_FREE | 2698 VI_DOINGINACT | VI_OWEINACT); 2699 if (flags != 0) { 2700 snprintf(buf2, sizeof(buf2), "|VI(0x%lx)", flags); 2701 strlcat(buf, buf2, sizeof(buf)); 2702 } 2703 printf(" flags (%s)\n", buf + 1); 2704 if (mtx_owned(VI_MTX(vp))) 2705 printf(" VI_LOCKed"); 2706 if (vp->v_object != NULL) 2707 printf(" v_object %p ref %d pages %d\n", 2708 vp->v_object, vp->v_object->ref_count, 2709 vp->v_object->resident_page_count); 2710 printf(" "); 2711 lockmgr_printinfo(vp->v_vnlock); 2712 if (vp->v_data != NULL) 2713 VOP_PRINT(vp); 2714 } 2715 2716 #ifdef DDB 2717 /* 2718 * List all of the locked vnodes in the system. 2719 * Called when debugging the kernel. 2720 */ 2721 DB_SHOW_COMMAND(lockedvnods, lockedvnodes) 2722 { 2723 struct mount *mp, *nmp; 2724 struct vnode *vp; 2725 2726 /* 2727 * Note: because this is DDB, we can't obey the locking semantics 2728 * for these structures, which means we could catch an inconsistent 2729 * state and dereference a nasty pointer. Not much to be done 2730 * about that. 2731 */ 2732 db_printf("Locked vnodes\n"); 2733 for (mp = TAILQ_FIRST(&mountlist); mp != NULL; mp = nmp) { 2734 nmp = TAILQ_NEXT(mp, mnt_list); 2735 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) { 2736 if (vp->v_type != VMARKER && 2737 VOP_ISLOCKED(vp)) 2738 vprint("", vp); 2739 } 2740 nmp = TAILQ_NEXT(mp, mnt_list); 2741 } 2742 } 2743 2744 /* 2745 * Show details about the given vnode. 2746 */ 2747 DB_SHOW_COMMAND(vnode, db_show_vnode) 2748 { 2749 struct vnode *vp; 2750 2751 if (!have_addr) 2752 return; 2753 vp = (struct vnode *)addr; 2754 vn_printf(vp, "vnode "); 2755 } 2756 2757 /* 2758 * Show details about the given mount point. 2759 */ 2760 DB_SHOW_COMMAND(mount, db_show_mount) 2761 { 2762 struct mount *mp; 2763 struct vfsopt *opt; 2764 struct statfs *sp; 2765 struct vnode *vp; 2766 char buf[512]; 2767 u_int flags; 2768 2769 if (!have_addr) { 2770 /* No address given, print short info about all mount points. */ 2771 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 2772 db_printf("%p %s on %s (%s)\n", mp, 2773 mp->mnt_stat.f_mntfromname, 2774 mp->mnt_stat.f_mntonname, 2775 mp->mnt_stat.f_fstypename); 2776 if (db_pager_quit) 2777 break; 2778 } 2779 db_printf("\nMore info: show mount <addr>\n"); 2780 return; 2781 } 2782 2783 mp = (struct mount *)addr; 2784 db_printf("%p %s on %s (%s)\n", mp, mp->mnt_stat.f_mntfromname, 2785 mp->mnt_stat.f_mntonname, mp->mnt_stat.f_fstypename); 2786 2787 buf[0] = '\0'; 2788 flags = mp->mnt_flag; 2789 #define MNT_FLAG(flag) do { \ 2790 if (flags & (flag)) { \ 2791 if (buf[0] != '\0') \ 2792 strlcat(buf, ", ", sizeof(buf)); \ 2793 strlcat(buf, (#flag) + 4, sizeof(buf)); \ 2794 flags &= ~(flag); \ 2795 } \ 2796 } while (0) 2797 MNT_FLAG(MNT_RDONLY); 2798 MNT_FLAG(MNT_SYNCHRONOUS); 2799 MNT_FLAG(MNT_NOEXEC); 2800 MNT_FLAG(MNT_NOSUID); 2801 MNT_FLAG(MNT_UNION); 2802 MNT_FLAG(MNT_ASYNC); 2803 MNT_FLAG(MNT_SUIDDIR); 2804 MNT_FLAG(MNT_SOFTDEP); 2805 MNT_FLAG(MNT_NOSYMFOLLOW); 2806 MNT_FLAG(MNT_GJOURNAL); 2807 MNT_FLAG(MNT_MULTILABEL); 2808 MNT_FLAG(MNT_ACLS); 2809 MNT_FLAG(MNT_NOATIME); 2810 MNT_FLAG(MNT_NOCLUSTERR); 2811 MNT_FLAG(MNT_NOCLUSTERW); 2812 MNT_FLAG(MNT_NFS4ACLS); 2813 MNT_FLAG(MNT_EXRDONLY); 2814 MNT_FLAG(MNT_EXPORTED); 2815 MNT_FLAG(MNT_DEFEXPORTED); 2816 MNT_FLAG(MNT_EXPORTANON); 2817 MNT_FLAG(MNT_EXKERB); 2818 MNT_FLAG(MNT_EXPUBLIC); 2819 MNT_FLAG(MNT_LOCAL); 2820 MNT_FLAG(MNT_QUOTA); 2821 MNT_FLAG(MNT_ROOTFS); 2822 MNT_FLAG(MNT_USER); 2823 MNT_FLAG(MNT_IGNORE); 2824 MNT_FLAG(MNT_UPDATE); 2825 MNT_FLAG(MNT_DELEXPORT); 2826 MNT_FLAG(MNT_RELOAD); 2827 MNT_FLAG(MNT_FORCE); 2828 MNT_FLAG(MNT_SNAPSHOT); 2829 MNT_FLAG(MNT_BYFSID); 2830 MNT_FLAG(MNT_SOFTDEP); 2831 #undef MNT_FLAG 2832 if (flags != 0) { 2833 if (buf[0] != '\0') 2834 strlcat(buf, ", ", sizeof(buf)); 2835 snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf), 2836 "0x%08x", flags); 2837 } 2838 db_printf(" mnt_flag = %s\n", buf); 2839 2840 buf[0] = '\0'; 2841 flags = mp->mnt_kern_flag; 2842 #define MNT_KERN_FLAG(flag) do { \ 2843 if (flags & (flag)) { \ 2844 if (buf[0] != '\0') \ 2845 strlcat(buf, ", ", sizeof(buf)); \ 2846 strlcat(buf, (#flag) + 5, sizeof(buf)); \ 2847 flags &= ~(flag); \ 2848 } \ 2849 } while (0) 2850 MNT_KERN_FLAG(MNTK_UNMOUNTF); 2851 MNT_KERN_FLAG(MNTK_ASYNC); 2852 MNT_KERN_FLAG(MNTK_SOFTDEP); 2853 MNT_KERN_FLAG(MNTK_NOINSMNTQ); 2854 MNT_KERN_FLAG(MNTK_DRAINING); 2855 MNT_KERN_FLAG(MNTK_REFEXPIRE); 2856 MNT_KERN_FLAG(MNTK_EXTENDED_SHARED); 2857 MNT_KERN_FLAG(MNTK_SHARED_WRITES); 2858 MNT_KERN_FLAG(MNTK_UNMOUNT); 2859 MNT_KERN_FLAG(MNTK_MWAIT); 2860 MNT_KERN_FLAG(MNTK_SUSPEND); 2861 MNT_KERN_FLAG(MNTK_SUSPEND2); 2862 MNT_KERN_FLAG(MNTK_SUSPENDED); 2863 MNT_KERN_FLAG(MNTK_MPSAFE); 2864 MNT_KERN_FLAG(MNTK_LOOKUP_SHARED); 2865 MNT_KERN_FLAG(MNTK_NOKNOTE); 2866 #undef MNT_KERN_FLAG 2867 if (flags != 0) { 2868 if (buf[0] != '\0') 2869 strlcat(buf, ", ", sizeof(buf)); 2870 snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf), 2871 "0x%08x", flags); 2872 } 2873 db_printf(" mnt_kern_flag = %s\n", buf); 2874 2875 db_printf(" mnt_opt = "); 2876 opt = TAILQ_FIRST(mp->mnt_opt); 2877 if (opt != NULL) { 2878 db_printf("%s", opt->name); 2879 opt = TAILQ_NEXT(opt, link); 2880 while (opt != NULL) { 2881 db_printf(", %s", opt->name); 2882 opt = TAILQ_NEXT(opt, link); 2883 } 2884 } 2885 db_printf("\n"); 2886 2887 sp = &mp->mnt_stat; 2888 db_printf(" mnt_stat = { version=%u type=%u flags=0x%016jx " 2889 "bsize=%ju iosize=%ju blocks=%ju bfree=%ju bavail=%jd files=%ju " 2890 "ffree=%jd syncwrites=%ju asyncwrites=%ju syncreads=%ju " 2891 "asyncreads=%ju namemax=%u owner=%u fsid=[%d, %d] }\n", 2892 (u_int)sp->f_version, (u_int)sp->f_type, (uintmax_t)sp->f_flags, 2893 (uintmax_t)sp->f_bsize, (uintmax_t)sp->f_iosize, 2894 (uintmax_t)sp->f_blocks, (uintmax_t)sp->f_bfree, 2895 (intmax_t)sp->f_bavail, (uintmax_t)sp->f_files, 2896 (intmax_t)sp->f_ffree, (uintmax_t)sp->f_syncwrites, 2897 (uintmax_t)sp->f_asyncwrites, (uintmax_t)sp->f_syncreads, 2898 (uintmax_t)sp->f_asyncreads, (u_int)sp->f_namemax, 2899 (u_int)sp->f_owner, (int)sp->f_fsid.val[0], (int)sp->f_fsid.val[1]); 2900 2901 db_printf(" mnt_cred = { uid=%u ruid=%u", 2902 (u_int)mp->mnt_cred->cr_uid, (u_int)mp->mnt_cred->cr_ruid); 2903 if (jailed(mp->mnt_cred)) 2904 db_printf(", jail=%d", mp->mnt_cred->cr_prison->pr_id); 2905 db_printf(" }\n"); 2906 db_printf(" mnt_ref = %d\n", mp->mnt_ref); 2907 db_printf(" mnt_gen = %d\n", mp->mnt_gen); 2908 db_printf(" mnt_nvnodelistsize = %d\n", mp->mnt_nvnodelistsize); 2909 db_printf(" mnt_writeopcount = %d\n", mp->mnt_writeopcount); 2910 db_printf(" mnt_noasync = %u\n", mp->mnt_noasync); 2911 db_printf(" mnt_maxsymlinklen = %d\n", mp->mnt_maxsymlinklen); 2912 db_printf(" mnt_iosize_max = %d\n", mp->mnt_iosize_max); 2913 db_printf(" mnt_hashseed = %u\n", mp->mnt_hashseed); 2914 db_printf(" mnt_secondary_writes = %d\n", mp->mnt_secondary_writes); 2915 db_printf(" mnt_secondary_accwrites = %d\n", 2916 mp->mnt_secondary_accwrites); 2917 db_printf(" mnt_gjprovider = %s\n", 2918 mp->mnt_gjprovider != NULL ? mp->mnt_gjprovider : "NULL"); 2919 db_printf("\n"); 2920 2921 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) { 2922 if (vp->v_type != VMARKER) { 2923 vn_printf(vp, "vnode "); 2924 if (db_pager_quit) 2925 break; 2926 } 2927 } 2928 } 2929 #endif /* DDB */ 2930 2931 /* 2932 * Fill in a struct xvfsconf based on a struct vfsconf. 2933 */ 2934 static void 2935 vfsconf2x(struct vfsconf *vfsp, struct xvfsconf *xvfsp) 2936 { 2937 2938 strcpy(xvfsp->vfc_name, vfsp->vfc_name); 2939 xvfsp->vfc_typenum = vfsp->vfc_typenum; 2940 xvfsp->vfc_refcount = vfsp->vfc_refcount; 2941 xvfsp->vfc_flags = vfsp->vfc_flags; 2942 /* 2943 * These are unused in userland, we keep them 2944 * to not break binary compatibility. 2945 */ 2946 xvfsp->vfc_vfsops = NULL; 2947 xvfsp->vfc_next = NULL; 2948 } 2949 2950 /* 2951 * Top level filesystem related information gathering. 2952 */ 2953 static int 2954 sysctl_vfs_conflist(SYSCTL_HANDLER_ARGS) 2955 { 2956 struct vfsconf *vfsp; 2957 struct xvfsconf xvfsp; 2958 int error; 2959 2960 error = 0; 2961 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) { 2962 bzero(&xvfsp, sizeof(xvfsp)); 2963 vfsconf2x(vfsp, &xvfsp); 2964 error = SYSCTL_OUT(req, &xvfsp, sizeof xvfsp); 2965 if (error) 2966 break; 2967 } 2968 return (error); 2969 } 2970 2971 SYSCTL_PROC(_vfs, OID_AUTO, conflist, CTLFLAG_RD, NULL, 0, sysctl_vfs_conflist, 2972 "S,xvfsconf", "List of all configured filesystems"); 2973 2974 #ifndef BURN_BRIDGES 2975 static int sysctl_ovfs_conf(SYSCTL_HANDLER_ARGS); 2976 2977 static int 2978 vfs_sysctl(SYSCTL_HANDLER_ARGS) 2979 { 2980 int *name = (int *)arg1 - 1; /* XXX */ 2981 u_int namelen = arg2 + 1; /* XXX */ 2982 struct vfsconf *vfsp; 2983 struct xvfsconf xvfsp; 2984 2985 printf("WARNING: userland calling deprecated sysctl, " 2986 "please rebuild world\n"); 2987 2988 #if 1 || defined(COMPAT_PRELITE2) 2989 /* Resolve ambiguity between VFS_VFSCONF and VFS_GENERIC. */ 2990 if (namelen == 1) 2991 return (sysctl_ovfs_conf(oidp, arg1, arg2, req)); 2992 #endif 2993 2994 switch (name[1]) { 2995 case VFS_MAXTYPENUM: 2996 if (namelen != 2) 2997 return (ENOTDIR); 2998 return (SYSCTL_OUT(req, &maxvfsconf, sizeof(int))); 2999 case VFS_CONF: 3000 if (namelen != 3) 3001 return (ENOTDIR); /* overloaded */ 3002 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) 3003 if (vfsp->vfc_typenum == name[2]) 3004 break; 3005 if (vfsp == NULL) 3006 return (EOPNOTSUPP); 3007 bzero(&xvfsp, sizeof(xvfsp)); 3008 vfsconf2x(vfsp, &xvfsp); 3009 return (SYSCTL_OUT(req, &xvfsp, sizeof(xvfsp))); 3010 } 3011 return (EOPNOTSUPP); 3012 } 3013 3014 static SYSCTL_NODE(_vfs, VFS_GENERIC, generic, CTLFLAG_RD | CTLFLAG_SKIP, 3015 vfs_sysctl, "Generic filesystem"); 3016 3017 #if 1 || defined(COMPAT_PRELITE2) 3018 3019 static int 3020 sysctl_ovfs_conf(SYSCTL_HANDLER_ARGS) 3021 { 3022 int error; 3023 struct vfsconf *vfsp; 3024 struct ovfsconf ovfs; 3025 3026 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) { 3027 bzero(&ovfs, sizeof(ovfs)); 3028 ovfs.vfc_vfsops = vfsp->vfc_vfsops; /* XXX used as flag */ 3029 strcpy(ovfs.vfc_name, vfsp->vfc_name); 3030 ovfs.vfc_index = vfsp->vfc_typenum; 3031 ovfs.vfc_refcount = vfsp->vfc_refcount; 3032 ovfs.vfc_flags = vfsp->vfc_flags; 3033 error = SYSCTL_OUT(req, &ovfs, sizeof ovfs); 3034 if (error) 3035 return error; 3036 } 3037 return 0; 3038 } 3039 3040 #endif /* 1 || COMPAT_PRELITE2 */ 3041 #endif /* !BURN_BRIDGES */ 3042 3043 #define KINFO_VNODESLOP 10 3044 #ifdef notyet 3045 /* 3046 * Dump vnode list (via sysctl). 3047 */ 3048 /* ARGSUSED */ 3049 static int 3050 sysctl_vnode(SYSCTL_HANDLER_ARGS) 3051 { 3052 struct xvnode *xvn; 3053 struct mount *mp; 3054 struct vnode *vp; 3055 int error, len, n; 3056 3057 /* 3058 * Stale numvnodes access is not fatal here. 3059 */ 3060 req->lock = 0; 3061 len = (numvnodes + KINFO_VNODESLOP) * sizeof *xvn; 3062 if (!req->oldptr) 3063 /* Make an estimate */ 3064 return (SYSCTL_OUT(req, 0, len)); 3065 3066 error = sysctl_wire_old_buffer(req, 0); 3067 if (error != 0) 3068 return (error); 3069 xvn = malloc(len, M_TEMP, M_ZERO | M_WAITOK); 3070 n = 0; 3071 mtx_lock(&mountlist_mtx); 3072 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 3073 if (vfs_busy(mp, MBF_NOWAIT | MBF_MNTLSTLOCK)) 3074 continue; 3075 MNT_ILOCK(mp); 3076 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) { 3077 if (n == len) 3078 break; 3079 vref(vp); 3080 xvn[n].xv_size = sizeof *xvn; 3081 xvn[n].xv_vnode = vp; 3082 xvn[n].xv_id = 0; /* XXX compat */ 3083 #define XV_COPY(field) xvn[n].xv_##field = vp->v_##field 3084 XV_COPY(usecount); 3085 XV_COPY(writecount); 3086 XV_COPY(holdcnt); 3087 XV_COPY(mount); 3088 XV_COPY(numoutput); 3089 XV_COPY(type); 3090 #undef XV_COPY 3091 xvn[n].xv_flag = vp->v_vflag; 3092 3093 switch (vp->v_type) { 3094 case VREG: 3095 case VDIR: 3096 case VLNK: 3097 break; 3098 case VBLK: 3099 case VCHR: 3100 if (vp->v_rdev == NULL) { 3101 vrele(vp); 3102 continue; 3103 } 3104 xvn[n].xv_dev = dev2udev(vp->v_rdev); 3105 break; 3106 case VSOCK: 3107 xvn[n].xv_socket = vp->v_socket; 3108 break; 3109 case VFIFO: 3110 xvn[n].xv_fifo = vp->v_fifoinfo; 3111 break; 3112 case VNON: 3113 case VBAD: 3114 default: 3115 /* shouldn't happen? */ 3116 vrele(vp); 3117 continue; 3118 } 3119 vrele(vp); 3120 ++n; 3121 } 3122 MNT_IUNLOCK(mp); 3123 mtx_lock(&mountlist_mtx); 3124 vfs_unbusy(mp); 3125 if (n == len) 3126 break; 3127 } 3128 mtx_unlock(&mountlist_mtx); 3129 3130 error = SYSCTL_OUT(req, xvn, n * sizeof *xvn); 3131 free(xvn, M_TEMP); 3132 return (error); 3133 } 3134 3135 SYSCTL_PROC(_kern, KERN_VNODE, vnode, CTLTYPE_OPAQUE|CTLFLAG_RD, 3136 0, 0, sysctl_vnode, "S,xvnode", ""); 3137 #endif 3138 3139 /* 3140 * Unmount all filesystems. The list is traversed in reverse order 3141 * of mounting to avoid dependencies. 3142 */ 3143 void 3144 vfs_unmountall(void) 3145 { 3146 struct mount *mp; 3147 struct thread *td; 3148 int error; 3149 3150 KASSERT(curthread != NULL, ("vfs_unmountall: NULL curthread")); 3151 CTR1(KTR_VFS, "%s: unmounting all filesystems", __func__); 3152 td = curthread; 3153 3154 /* 3155 * Since this only runs when rebooting, it is not interlocked. 3156 */ 3157 while(!TAILQ_EMPTY(&mountlist)) { 3158 mp = TAILQ_LAST(&mountlist, mntlist); 3159 error = dounmount(mp, MNT_FORCE, td); 3160 if (error) { 3161 TAILQ_REMOVE(&mountlist, mp, mnt_list); 3162 /* 3163 * XXX: Due to the way in which we mount the root 3164 * file system off of devfs, devfs will generate a 3165 * "busy" warning when we try to unmount it before 3166 * the root. Don't print a warning as a result in 3167 * order to avoid false positive errors that may 3168 * cause needless upset. 3169 */ 3170 if (strcmp(mp->mnt_vfc->vfc_name, "devfs") != 0) { 3171 printf("unmount of %s failed (", 3172 mp->mnt_stat.f_mntonname); 3173 if (error == EBUSY) 3174 printf("BUSY)\n"); 3175 else 3176 printf("%d)\n", error); 3177 } 3178 } else { 3179 /* The unmount has removed mp from the mountlist */ 3180 } 3181 } 3182 } 3183 3184 /* 3185 * perform msync on all vnodes under a mount point 3186 * the mount point must be locked. 3187 */ 3188 void 3189 vfs_msync(struct mount *mp, int flags) 3190 { 3191 struct vnode *vp, *mvp; 3192 struct vm_object *obj; 3193 3194 CTR2(KTR_VFS, "%s: mp %p", __func__, mp); 3195 MNT_ILOCK(mp); 3196 MNT_VNODE_FOREACH(vp, mp, mvp) { 3197 VI_LOCK(vp); 3198 obj = vp->v_object; 3199 if (obj != NULL && (obj->flags & OBJ_MIGHTBEDIRTY) != 0 && 3200 (flags == MNT_WAIT || VOP_ISLOCKED(vp) == 0)) { 3201 MNT_IUNLOCK(mp); 3202 if (!vget(vp, 3203 LK_EXCLUSIVE | LK_RETRY | LK_INTERLOCK, 3204 curthread)) { 3205 if (vp->v_vflag & VV_NOSYNC) { /* unlinked */ 3206 vput(vp); 3207 MNT_ILOCK(mp); 3208 continue; 3209 } 3210 3211 obj = vp->v_object; 3212 if (obj != NULL) { 3213 VM_OBJECT_LOCK(obj); 3214 vm_object_page_clean(obj, 0, 0, 3215 flags == MNT_WAIT ? 3216 OBJPC_SYNC : OBJPC_NOSYNC); 3217 VM_OBJECT_UNLOCK(obj); 3218 } 3219 vput(vp); 3220 } 3221 MNT_ILOCK(mp); 3222 } else 3223 VI_UNLOCK(vp); 3224 } 3225 MNT_IUNLOCK(mp); 3226 } 3227 3228 /* 3229 * Mark a vnode as free, putting it up for recycling. 3230 */ 3231 static void 3232 vfree(struct vnode *vp) 3233 { 3234 3235 ASSERT_VI_LOCKED(vp, "vfree"); 3236 mtx_lock(&vnode_free_list_mtx); 3237 VNASSERT(vp->v_op != NULL, vp, ("vfree: vnode already reclaimed.")); 3238 VNASSERT((vp->v_iflag & VI_FREE) == 0, vp, ("vnode already free")); 3239 VNASSERT(VSHOULDFREE(vp), vp, ("vfree: freeing when we shouldn't")); 3240 VNASSERT((vp->v_iflag & VI_DOOMED) == 0, vp, 3241 ("vfree: Freeing doomed vnode")); 3242 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 3243 if (vp->v_iflag & VI_AGE) { 3244 TAILQ_INSERT_HEAD(&vnode_free_list, vp, v_freelist); 3245 } else { 3246 TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_freelist); 3247 } 3248 freevnodes++; 3249 vp->v_iflag &= ~VI_AGE; 3250 vp->v_iflag |= VI_FREE; 3251 mtx_unlock(&vnode_free_list_mtx); 3252 } 3253 3254 /* 3255 * Opposite of vfree() - mark a vnode as in use. 3256 */ 3257 static void 3258 vbusy(struct vnode *vp) 3259 { 3260 ASSERT_VI_LOCKED(vp, "vbusy"); 3261 VNASSERT((vp->v_iflag & VI_FREE) != 0, vp, ("vnode not free")); 3262 VNASSERT(vp->v_op != NULL, vp, ("vbusy: vnode already reclaimed.")); 3263 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 3264 3265 mtx_lock(&vnode_free_list_mtx); 3266 TAILQ_REMOVE(&vnode_free_list, vp, v_freelist); 3267 freevnodes--; 3268 vp->v_iflag &= ~(VI_FREE|VI_AGE); 3269 mtx_unlock(&vnode_free_list_mtx); 3270 } 3271 3272 static void 3273 destroy_vpollinfo(struct vpollinfo *vi) 3274 { 3275 knlist_destroy(&vi->vpi_selinfo.si_note); 3276 mtx_destroy(&vi->vpi_lock); 3277 uma_zfree(vnodepoll_zone, vi); 3278 } 3279 3280 /* 3281 * Initalize per-vnode helper structure to hold poll-related state. 3282 */ 3283 void 3284 v_addpollinfo(struct vnode *vp) 3285 { 3286 struct vpollinfo *vi; 3287 3288 if (vp->v_pollinfo != NULL) 3289 return; 3290 vi = uma_zalloc(vnodepoll_zone, M_WAITOK); 3291 mtx_init(&vi->vpi_lock, "vnode pollinfo", NULL, MTX_DEF); 3292 knlist_init(&vi->vpi_selinfo.si_note, vp, vfs_knllock, 3293 vfs_knlunlock, vfs_knl_assert_locked, vfs_knl_assert_unlocked); 3294 VI_LOCK(vp); 3295 if (vp->v_pollinfo != NULL) { 3296 VI_UNLOCK(vp); 3297 destroy_vpollinfo(vi); 3298 return; 3299 } 3300 vp->v_pollinfo = vi; 3301 VI_UNLOCK(vp); 3302 } 3303 3304 /* 3305 * Record a process's interest in events which might happen to 3306 * a vnode. Because poll uses the historic select-style interface 3307 * internally, this routine serves as both the ``check for any 3308 * pending events'' and the ``record my interest in future events'' 3309 * functions. (These are done together, while the lock is held, 3310 * to avoid race conditions.) 3311 */ 3312 int 3313 vn_pollrecord(struct vnode *vp, struct thread *td, int events) 3314 { 3315 3316 v_addpollinfo(vp); 3317 mtx_lock(&vp->v_pollinfo->vpi_lock); 3318 if (vp->v_pollinfo->vpi_revents & events) { 3319 /* 3320 * This leaves events we are not interested 3321 * in available for the other process which 3322 * which presumably had requested them 3323 * (otherwise they would never have been 3324 * recorded). 3325 */ 3326 events &= vp->v_pollinfo->vpi_revents; 3327 vp->v_pollinfo->vpi_revents &= ~events; 3328 3329 mtx_unlock(&vp->v_pollinfo->vpi_lock); 3330 return (events); 3331 } 3332 vp->v_pollinfo->vpi_events |= events; 3333 selrecord(td, &vp->v_pollinfo->vpi_selinfo); 3334 mtx_unlock(&vp->v_pollinfo->vpi_lock); 3335 return (0); 3336 } 3337 3338 /* 3339 * Routine to create and manage a filesystem syncer vnode. 3340 */ 3341 #define sync_close ((int (*)(struct vop_close_args *))nullop) 3342 static int sync_fsync(struct vop_fsync_args *); 3343 static int sync_inactive(struct vop_inactive_args *); 3344 static int sync_reclaim(struct vop_reclaim_args *); 3345 3346 static struct vop_vector sync_vnodeops = { 3347 .vop_bypass = VOP_EOPNOTSUPP, 3348 .vop_close = sync_close, /* close */ 3349 .vop_fsync = sync_fsync, /* fsync */ 3350 .vop_inactive = sync_inactive, /* inactive */ 3351 .vop_reclaim = sync_reclaim, /* reclaim */ 3352 .vop_lock1 = vop_stdlock, /* lock */ 3353 .vop_unlock = vop_stdunlock, /* unlock */ 3354 .vop_islocked = vop_stdislocked, /* islocked */ 3355 }; 3356 3357 /* 3358 * Create a new filesystem syncer vnode for the specified mount point. 3359 */ 3360 int 3361 vfs_allocate_syncvnode(struct mount *mp) 3362 { 3363 struct vnode *vp; 3364 struct bufobj *bo; 3365 static long start, incr, next; 3366 int error; 3367 3368 /* Allocate a new vnode */ 3369 if ((error = getnewvnode("syncer", mp, &sync_vnodeops, &vp)) != 0) { 3370 mp->mnt_syncer = NULL; 3371 return (error); 3372 } 3373 vp->v_type = VNON; 3374 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 3375 vp->v_vflag |= VV_FORCEINSMQ; 3376 error = insmntque(vp, mp); 3377 if (error != 0) 3378 panic("vfs_allocate_syncvnode: insmntque failed"); 3379 vp->v_vflag &= ~VV_FORCEINSMQ; 3380 VOP_UNLOCK(vp, 0); 3381 /* 3382 * Place the vnode onto the syncer worklist. We attempt to 3383 * scatter them about on the list so that they will go off 3384 * at evenly distributed times even if all the filesystems 3385 * are mounted at once. 3386 */ 3387 next += incr; 3388 if (next == 0 || next > syncer_maxdelay) { 3389 start /= 2; 3390 incr /= 2; 3391 if (start == 0) { 3392 start = syncer_maxdelay / 2; 3393 incr = syncer_maxdelay; 3394 } 3395 next = start; 3396 } 3397 bo = &vp->v_bufobj; 3398 BO_LOCK(bo); 3399 vn_syncer_add_to_worklist(bo, syncdelay > 0 ? next % syncdelay : 0); 3400 /* XXX - vn_syncer_add_to_worklist() also grabs and drops sync_mtx. */ 3401 mtx_lock(&sync_mtx); 3402 sync_vnode_count++; 3403 mtx_unlock(&sync_mtx); 3404 BO_UNLOCK(bo); 3405 mp->mnt_syncer = vp; 3406 return (0); 3407 } 3408 3409 /* 3410 * Do a lazy sync of the filesystem. 3411 */ 3412 static int 3413 sync_fsync(struct vop_fsync_args *ap) 3414 { 3415 struct vnode *syncvp = ap->a_vp; 3416 struct mount *mp = syncvp->v_mount; 3417 int error; 3418 struct bufobj *bo; 3419 3420 /* 3421 * We only need to do something if this is a lazy evaluation. 3422 */ 3423 if (ap->a_waitfor != MNT_LAZY) 3424 return (0); 3425 3426 /* 3427 * Move ourselves to the back of the sync list. 3428 */ 3429 bo = &syncvp->v_bufobj; 3430 BO_LOCK(bo); 3431 vn_syncer_add_to_worklist(bo, syncdelay); 3432 BO_UNLOCK(bo); 3433 3434 /* 3435 * Walk the list of vnodes pushing all that are dirty and 3436 * not already on the sync list. 3437 */ 3438 mtx_lock(&mountlist_mtx); 3439 if (vfs_busy(mp, MBF_NOWAIT | MBF_MNTLSTLOCK) != 0) { 3440 mtx_unlock(&mountlist_mtx); 3441 return (0); 3442 } 3443 if (vn_start_write(NULL, &mp, V_NOWAIT) != 0) { 3444 vfs_unbusy(mp); 3445 return (0); 3446 } 3447 MNT_ILOCK(mp); 3448 mp->mnt_noasync++; 3449 mp->mnt_kern_flag &= ~MNTK_ASYNC; 3450 MNT_IUNLOCK(mp); 3451 vfs_msync(mp, MNT_NOWAIT); 3452 error = VFS_SYNC(mp, MNT_LAZY); 3453 MNT_ILOCK(mp); 3454 mp->mnt_noasync--; 3455 if ((mp->mnt_flag & MNT_ASYNC) != 0 && mp->mnt_noasync == 0) 3456 mp->mnt_kern_flag |= MNTK_ASYNC; 3457 MNT_IUNLOCK(mp); 3458 vn_finished_write(mp); 3459 vfs_unbusy(mp); 3460 return (error); 3461 } 3462 3463 /* 3464 * The syncer vnode is no referenced. 3465 */ 3466 static int 3467 sync_inactive(struct vop_inactive_args *ap) 3468 { 3469 3470 vgone(ap->a_vp); 3471 return (0); 3472 } 3473 3474 /* 3475 * The syncer vnode is no longer needed and is being decommissioned. 3476 * 3477 * Modifications to the worklist must be protected by sync_mtx. 3478 */ 3479 static int 3480 sync_reclaim(struct vop_reclaim_args *ap) 3481 { 3482 struct vnode *vp = ap->a_vp; 3483 struct bufobj *bo; 3484 3485 bo = &vp->v_bufobj; 3486 BO_LOCK(bo); 3487 vp->v_mount->mnt_syncer = NULL; 3488 if (bo->bo_flag & BO_ONWORKLST) { 3489 mtx_lock(&sync_mtx); 3490 LIST_REMOVE(bo, bo_synclist); 3491 syncer_worklist_len--; 3492 sync_vnode_count--; 3493 mtx_unlock(&sync_mtx); 3494 bo->bo_flag &= ~BO_ONWORKLST; 3495 } 3496 BO_UNLOCK(bo); 3497 3498 return (0); 3499 } 3500 3501 /* 3502 * Check if vnode represents a disk device 3503 */ 3504 int 3505 vn_isdisk(struct vnode *vp, int *errp) 3506 { 3507 int error; 3508 3509 error = 0; 3510 dev_lock(); 3511 if (vp->v_type != VCHR) 3512 error = ENOTBLK; 3513 else if (vp->v_rdev == NULL) 3514 error = ENXIO; 3515 else if (vp->v_rdev->si_devsw == NULL) 3516 error = ENXIO; 3517 else if (!(vp->v_rdev->si_devsw->d_flags & D_DISK)) 3518 error = ENOTBLK; 3519 dev_unlock(); 3520 if (errp != NULL) 3521 *errp = error; 3522 return (error == 0); 3523 } 3524 3525 /* 3526 * Common filesystem object access control check routine. Accepts a 3527 * vnode's type, "mode", uid and gid, requested access mode, credentials, 3528 * and optional call-by-reference privused argument allowing vaccess() 3529 * to indicate to the caller whether privilege was used to satisfy the 3530 * request (obsoleted). Returns 0 on success, or an errno on failure. 3531 * 3532 * The ifdef'd CAPABILITIES version is here for reference, but is not 3533 * actually used. 3534 */ 3535 int 3536 vaccess(enum vtype type, mode_t file_mode, uid_t file_uid, gid_t file_gid, 3537 accmode_t accmode, struct ucred *cred, int *privused) 3538 { 3539 accmode_t dac_granted; 3540 accmode_t priv_granted; 3541 3542 KASSERT((accmode & ~(VEXEC | VWRITE | VREAD | VADMIN | VAPPEND)) == 0, 3543 ("invalid bit in accmode")); 3544 KASSERT((accmode & VAPPEND) == 0 || (accmode & VWRITE), 3545 ("VAPPEND without VWRITE")); 3546 3547 /* 3548 * Look for a normal, non-privileged way to access the file/directory 3549 * as requested. If it exists, go with that. 3550 */ 3551 3552 if (privused != NULL) 3553 *privused = 0; 3554 3555 dac_granted = 0; 3556 3557 /* Check the owner. */ 3558 if (cred->cr_uid == file_uid) { 3559 dac_granted |= VADMIN; 3560 if (file_mode & S_IXUSR) 3561 dac_granted |= VEXEC; 3562 if (file_mode & S_IRUSR) 3563 dac_granted |= VREAD; 3564 if (file_mode & S_IWUSR) 3565 dac_granted |= (VWRITE | VAPPEND); 3566 3567 if ((accmode & dac_granted) == accmode) 3568 return (0); 3569 3570 goto privcheck; 3571 } 3572 3573 /* Otherwise, check the groups (first match) */ 3574 if (groupmember(file_gid, cred)) { 3575 if (file_mode & S_IXGRP) 3576 dac_granted |= VEXEC; 3577 if (file_mode & S_IRGRP) 3578 dac_granted |= VREAD; 3579 if (file_mode & S_IWGRP) 3580 dac_granted |= (VWRITE | VAPPEND); 3581 3582 if ((accmode & dac_granted) == accmode) 3583 return (0); 3584 3585 goto privcheck; 3586 } 3587 3588 /* Otherwise, check everyone else. */ 3589 if (file_mode & S_IXOTH) 3590 dac_granted |= VEXEC; 3591 if (file_mode & S_IROTH) 3592 dac_granted |= VREAD; 3593 if (file_mode & S_IWOTH) 3594 dac_granted |= (VWRITE | VAPPEND); 3595 if ((accmode & dac_granted) == accmode) 3596 return (0); 3597 3598 privcheck: 3599 /* 3600 * Build a privilege mask to determine if the set of privileges 3601 * satisfies the requirements when combined with the granted mask 3602 * from above. For each privilege, if the privilege is required, 3603 * bitwise or the request type onto the priv_granted mask. 3604 */ 3605 priv_granted = 0; 3606 3607 if (type == VDIR) { 3608 /* 3609 * For directories, use PRIV_VFS_LOOKUP to satisfy VEXEC 3610 * requests, instead of PRIV_VFS_EXEC. 3611 */ 3612 if ((accmode & VEXEC) && ((dac_granted & VEXEC) == 0) && 3613 !priv_check_cred(cred, PRIV_VFS_LOOKUP, 0)) 3614 priv_granted |= VEXEC; 3615 } else { 3616 if ((accmode & VEXEC) && ((dac_granted & VEXEC) == 0) && 3617 !priv_check_cred(cred, PRIV_VFS_EXEC, 0)) 3618 priv_granted |= VEXEC; 3619 } 3620 3621 if ((accmode & VREAD) && ((dac_granted & VREAD) == 0) && 3622 !priv_check_cred(cred, PRIV_VFS_READ, 0)) 3623 priv_granted |= VREAD; 3624 3625 if ((accmode & VWRITE) && ((dac_granted & VWRITE) == 0) && 3626 !priv_check_cred(cred, PRIV_VFS_WRITE, 0)) 3627 priv_granted |= (VWRITE | VAPPEND); 3628 3629 if ((accmode & VADMIN) && ((dac_granted & VADMIN) == 0) && 3630 !priv_check_cred(cred, PRIV_VFS_ADMIN, 0)) 3631 priv_granted |= VADMIN; 3632 3633 if ((accmode & (priv_granted | dac_granted)) == accmode) { 3634 /* XXX audit: privilege used */ 3635 if (privused != NULL) 3636 *privused = 1; 3637 return (0); 3638 } 3639 3640 return ((accmode & VADMIN) ? EPERM : EACCES); 3641 } 3642 3643 /* 3644 * Credential check based on process requesting service, and per-attribute 3645 * permissions. 3646 */ 3647 int 3648 extattr_check_cred(struct vnode *vp, int attrnamespace, struct ucred *cred, 3649 struct thread *td, accmode_t accmode) 3650 { 3651 3652 /* 3653 * Kernel-invoked always succeeds. 3654 */ 3655 if (cred == NOCRED) 3656 return (0); 3657 3658 /* 3659 * Do not allow privileged processes in jail to directly manipulate 3660 * system attributes. 3661 */ 3662 switch (attrnamespace) { 3663 case EXTATTR_NAMESPACE_SYSTEM: 3664 /* Potentially should be: return (EPERM); */ 3665 return (priv_check_cred(cred, PRIV_VFS_EXTATTR_SYSTEM, 0)); 3666 case EXTATTR_NAMESPACE_USER: 3667 return (VOP_ACCESS(vp, accmode, cred, td)); 3668 default: 3669 return (EPERM); 3670 } 3671 } 3672 3673 #ifdef DEBUG_VFS_LOCKS 3674 /* 3675 * This only exists to supress warnings from unlocked specfs accesses. It is 3676 * no longer ok to have an unlocked VFS. 3677 */ 3678 #define IGNORE_LOCK(vp) (panicstr != NULL || (vp) == NULL || \ 3679 (vp)->v_type == VCHR || (vp)->v_type == VBAD) 3680 3681 int vfs_badlock_ddb = 1; /* Drop into debugger on violation. */ 3682 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_ddb, CTLFLAG_RW, &vfs_badlock_ddb, 0, ""); 3683 3684 int vfs_badlock_mutex = 1; /* Check for interlock across VOPs. */ 3685 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_mutex, CTLFLAG_RW, &vfs_badlock_mutex, 0, ""); 3686 3687 int vfs_badlock_print = 1; /* Print lock violations. */ 3688 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_print, CTLFLAG_RW, &vfs_badlock_print, 0, ""); 3689 3690 #ifdef KDB 3691 int vfs_badlock_backtrace = 1; /* Print backtrace at lock violations. */ 3692 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_backtrace, CTLFLAG_RW, &vfs_badlock_backtrace, 0, ""); 3693 #endif 3694 3695 static void 3696 vfs_badlock(const char *msg, const char *str, struct vnode *vp) 3697 { 3698 3699 #ifdef KDB 3700 if (vfs_badlock_backtrace) 3701 kdb_backtrace(); 3702 #endif 3703 if (vfs_badlock_print) 3704 printf("%s: %p %s\n", str, (void *)vp, msg); 3705 if (vfs_badlock_ddb) 3706 kdb_enter(KDB_WHY_VFSLOCK, "lock violation"); 3707 } 3708 3709 void 3710 assert_vi_locked(struct vnode *vp, const char *str) 3711 { 3712 3713 if (vfs_badlock_mutex && !mtx_owned(VI_MTX(vp))) 3714 vfs_badlock("interlock is not locked but should be", str, vp); 3715 } 3716 3717 void 3718 assert_vi_unlocked(struct vnode *vp, const char *str) 3719 { 3720 3721 if (vfs_badlock_mutex && mtx_owned(VI_MTX(vp))) 3722 vfs_badlock("interlock is locked but should not be", str, vp); 3723 } 3724 3725 void 3726 assert_vop_locked(struct vnode *vp, const char *str) 3727 { 3728 3729 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) == 0) 3730 vfs_badlock("is not locked but should be", str, vp); 3731 } 3732 3733 void 3734 assert_vop_unlocked(struct vnode *vp, const char *str) 3735 { 3736 3737 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) == LK_EXCLUSIVE) 3738 vfs_badlock("is locked but should not be", str, vp); 3739 } 3740 3741 void 3742 assert_vop_elocked(struct vnode *vp, const char *str) 3743 { 3744 3745 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) != LK_EXCLUSIVE) 3746 vfs_badlock("is not exclusive locked but should be", str, vp); 3747 } 3748 3749 #if 0 3750 void 3751 assert_vop_elocked_other(struct vnode *vp, const char *str) 3752 { 3753 3754 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) != LK_EXCLOTHER) 3755 vfs_badlock("is not exclusive locked by another thread", 3756 str, vp); 3757 } 3758 3759 void 3760 assert_vop_slocked(struct vnode *vp, const char *str) 3761 { 3762 3763 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) != LK_SHARED) 3764 vfs_badlock("is not locked shared but should be", str, vp); 3765 } 3766 #endif /* 0 */ 3767 #endif /* DEBUG_VFS_LOCKS */ 3768 3769 void 3770 vop_rename_fail(struct vop_rename_args *ap) 3771 { 3772 3773 if (ap->a_tvp != NULL) 3774 vput(ap->a_tvp); 3775 if (ap->a_tdvp == ap->a_tvp) 3776 vrele(ap->a_tdvp); 3777 else 3778 vput(ap->a_tdvp); 3779 vrele(ap->a_fdvp); 3780 vrele(ap->a_fvp); 3781 } 3782 3783 void 3784 vop_rename_pre(void *ap) 3785 { 3786 struct vop_rename_args *a = ap; 3787 3788 #ifdef DEBUG_VFS_LOCKS 3789 if (a->a_tvp) 3790 ASSERT_VI_UNLOCKED(a->a_tvp, "VOP_RENAME"); 3791 ASSERT_VI_UNLOCKED(a->a_tdvp, "VOP_RENAME"); 3792 ASSERT_VI_UNLOCKED(a->a_fvp, "VOP_RENAME"); 3793 ASSERT_VI_UNLOCKED(a->a_fdvp, "VOP_RENAME"); 3794 3795 /* Check the source (from). */ 3796 if (a->a_tdvp->v_vnlock != a->a_fdvp->v_vnlock && 3797 (a->a_tvp == NULL || a->a_tvp->v_vnlock != a->a_fdvp->v_vnlock)) 3798 ASSERT_VOP_UNLOCKED(a->a_fdvp, "vop_rename: fdvp locked"); 3799 if (a->a_tvp == NULL || a->a_tvp->v_vnlock != a->a_fvp->v_vnlock) 3800 ASSERT_VOP_UNLOCKED(a->a_fvp, "vop_rename: fvp locked"); 3801 3802 /* Check the target. */ 3803 if (a->a_tvp) 3804 ASSERT_VOP_LOCKED(a->a_tvp, "vop_rename: tvp not locked"); 3805 ASSERT_VOP_LOCKED(a->a_tdvp, "vop_rename: tdvp not locked"); 3806 #endif 3807 if (a->a_tdvp != a->a_fdvp) 3808 vhold(a->a_fdvp); 3809 if (a->a_tvp != a->a_fvp) 3810 vhold(a->a_fvp); 3811 vhold(a->a_tdvp); 3812 if (a->a_tvp) 3813 vhold(a->a_tvp); 3814 } 3815 3816 void 3817 vop_strategy_pre(void *ap) 3818 { 3819 #ifdef DEBUG_VFS_LOCKS 3820 struct vop_strategy_args *a; 3821 struct buf *bp; 3822 3823 a = ap; 3824 bp = a->a_bp; 3825 3826 /* 3827 * Cluster ops lock their component buffers but not the IO container. 3828 */ 3829 if ((bp->b_flags & B_CLUSTER) != 0) 3830 return; 3831 3832 if (!BUF_ISLOCKED(bp)) { 3833 if (vfs_badlock_print) 3834 printf( 3835 "VOP_STRATEGY: bp is not locked but should be\n"); 3836 if (vfs_badlock_ddb) 3837 kdb_enter(KDB_WHY_VFSLOCK, "lock violation"); 3838 } 3839 #endif 3840 } 3841 3842 void 3843 vop_lookup_pre(void *ap) 3844 { 3845 #ifdef DEBUG_VFS_LOCKS 3846 struct vop_lookup_args *a; 3847 struct vnode *dvp; 3848 3849 a = ap; 3850 dvp = a->a_dvp; 3851 ASSERT_VI_UNLOCKED(dvp, "VOP_LOOKUP"); 3852 ASSERT_VOP_LOCKED(dvp, "VOP_LOOKUP"); 3853 #endif 3854 } 3855 3856 void 3857 vop_lookup_post(void *ap, int rc) 3858 { 3859 #ifdef DEBUG_VFS_LOCKS 3860 struct vop_lookup_args *a; 3861 struct vnode *dvp; 3862 struct vnode *vp; 3863 3864 a = ap; 3865 dvp = a->a_dvp; 3866 vp = *(a->a_vpp); 3867 3868 ASSERT_VI_UNLOCKED(dvp, "VOP_LOOKUP"); 3869 ASSERT_VOP_LOCKED(dvp, "VOP_LOOKUP"); 3870 3871 if (!rc) 3872 ASSERT_VOP_LOCKED(vp, "VOP_LOOKUP (child)"); 3873 #endif 3874 } 3875 3876 void 3877 vop_lock_pre(void *ap) 3878 { 3879 #ifdef DEBUG_VFS_LOCKS 3880 struct vop_lock1_args *a = ap; 3881 3882 if ((a->a_flags & LK_INTERLOCK) == 0) 3883 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_LOCK"); 3884 else 3885 ASSERT_VI_LOCKED(a->a_vp, "VOP_LOCK"); 3886 #endif 3887 } 3888 3889 void 3890 vop_lock_post(void *ap, int rc) 3891 { 3892 #ifdef DEBUG_VFS_LOCKS 3893 struct vop_lock1_args *a = ap; 3894 3895 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_LOCK"); 3896 if (rc == 0) 3897 ASSERT_VOP_LOCKED(a->a_vp, "VOP_LOCK"); 3898 #endif 3899 } 3900 3901 void 3902 vop_unlock_pre(void *ap) 3903 { 3904 #ifdef DEBUG_VFS_LOCKS 3905 struct vop_unlock_args *a = ap; 3906 3907 if (a->a_flags & LK_INTERLOCK) 3908 ASSERT_VI_LOCKED(a->a_vp, "VOP_UNLOCK"); 3909 ASSERT_VOP_LOCKED(a->a_vp, "VOP_UNLOCK"); 3910 #endif 3911 } 3912 3913 void 3914 vop_unlock_post(void *ap, int rc) 3915 { 3916 #ifdef DEBUG_VFS_LOCKS 3917 struct vop_unlock_args *a = ap; 3918 3919 if (a->a_flags & LK_INTERLOCK) 3920 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_UNLOCK"); 3921 #endif 3922 } 3923 3924 void 3925 vop_create_post(void *ap, int rc) 3926 { 3927 struct vop_create_args *a = ap; 3928 3929 if (!rc) 3930 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 3931 } 3932 3933 void 3934 vop_link_post(void *ap, int rc) 3935 { 3936 struct vop_link_args *a = ap; 3937 3938 if (!rc) { 3939 VFS_KNOTE_LOCKED(a->a_vp, NOTE_LINK); 3940 VFS_KNOTE_LOCKED(a->a_tdvp, NOTE_WRITE); 3941 } 3942 } 3943 3944 void 3945 vop_mkdir_post(void *ap, int rc) 3946 { 3947 struct vop_mkdir_args *a = ap; 3948 3949 if (!rc) 3950 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE | NOTE_LINK); 3951 } 3952 3953 void 3954 vop_mknod_post(void *ap, int rc) 3955 { 3956 struct vop_mknod_args *a = ap; 3957 3958 if (!rc) 3959 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 3960 } 3961 3962 void 3963 vop_remove_post(void *ap, int rc) 3964 { 3965 struct vop_remove_args *a = ap; 3966 3967 if (!rc) { 3968 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 3969 VFS_KNOTE_LOCKED(a->a_vp, NOTE_DELETE); 3970 } 3971 } 3972 3973 void 3974 vop_rename_post(void *ap, int rc) 3975 { 3976 struct vop_rename_args *a = ap; 3977 3978 if (!rc) { 3979 VFS_KNOTE_UNLOCKED(a->a_fdvp, NOTE_WRITE); 3980 VFS_KNOTE_UNLOCKED(a->a_tdvp, NOTE_WRITE); 3981 VFS_KNOTE_UNLOCKED(a->a_fvp, NOTE_RENAME); 3982 if (a->a_tvp) 3983 VFS_KNOTE_UNLOCKED(a->a_tvp, NOTE_DELETE); 3984 } 3985 if (a->a_tdvp != a->a_fdvp) 3986 vdrop(a->a_fdvp); 3987 if (a->a_tvp != a->a_fvp) 3988 vdrop(a->a_fvp); 3989 vdrop(a->a_tdvp); 3990 if (a->a_tvp) 3991 vdrop(a->a_tvp); 3992 } 3993 3994 void 3995 vop_rmdir_post(void *ap, int rc) 3996 { 3997 struct vop_rmdir_args *a = ap; 3998 3999 if (!rc) { 4000 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE | NOTE_LINK); 4001 VFS_KNOTE_LOCKED(a->a_vp, NOTE_DELETE); 4002 } 4003 } 4004 4005 void 4006 vop_setattr_post(void *ap, int rc) 4007 { 4008 struct vop_setattr_args *a = ap; 4009 4010 if (!rc) 4011 VFS_KNOTE_LOCKED(a->a_vp, NOTE_ATTRIB); 4012 } 4013 4014 void 4015 vop_symlink_post(void *ap, int rc) 4016 { 4017 struct vop_symlink_args *a = ap; 4018 4019 if (!rc) 4020 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 4021 } 4022 4023 static struct knlist fs_knlist; 4024 4025 static void 4026 vfs_event_init(void *arg) 4027 { 4028 knlist_init_mtx(&fs_knlist, NULL); 4029 } 4030 /* XXX - correct order? */ 4031 SYSINIT(vfs_knlist, SI_SUB_VFS, SI_ORDER_ANY, vfs_event_init, NULL); 4032 4033 void 4034 vfs_event_signal(fsid_t *fsid, u_int32_t event, intptr_t data __unused) 4035 { 4036 4037 KNOTE_UNLOCKED(&fs_knlist, event); 4038 } 4039 4040 static int filt_fsattach(struct knote *kn); 4041 static void filt_fsdetach(struct knote *kn); 4042 static int filt_fsevent(struct knote *kn, long hint); 4043 4044 struct filterops fs_filtops = { 4045 .f_isfd = 0, 4046 .f_attach = filt_fsattach, 4047 .f_detach = filt_fsdetach, 4048 .f_event = filt_fsevent 4049 }; 4050 4051 static int 4052 filt_fsattach(struct knote *kn) 4053 { 4054 4055 kn->kn_flags |= EV_CLEAR; 4056 knlist_add(&fs_knlist, kn, 0); 4057 return (0); 4058 } 4059 4060 static void 4061 filt_fsdetach(struct knote *kn) 4062 { 4063 4064 knlist_remove(&fs_knlist, kn, 0); 4065 } 4066 4067 static int 4068 filt_fsevent(struct knote *kn, long hint) 4069 { 4070 4071 kn->kn_fflags |= hint; 4072 return (kn->kn_fflags != 0); 4073 } 4074 4075 static int 4076 sysctl_vfs_ctl(SYSCTL_HANDLER_ARGS) 4077 { 4078 struct vfsidctl vc; 4079 int error; 4080 struct mount *mp; 4081 4082 error = SYSCTL_IN(req, &vc, sizeof(vc)); 4083 if (error) 4084 return (error); 4085 if (vc.vc_vers != VFS_CTL_VERS1) 4086 return (EINVAL); 4087 mp = vfs_getvfs(&vc.vc_fsid); 4088 if (mp == NULL) 4089 return (ENOENT); 4090 /* ensure that a specific sysctl goes to the right filesystem. */ 4091 if (strcmp(vc.vc_fstypename, "*") != 0 && 4092 strcmp(vc.vc_fstypename, mp->mnt_vfc->vfc_name) != 0) { 4093 vfs_rel(mp); 4094 return (EINVAL); 4095 } 4096 VCTLTOREQ(&vc, req); 4097 error = VFS_SYSCTL(mp, vc.vc_op, req); 4098 vfs_rel(mp); 4099 return (error); 4100 } 4101 4102 SYSCTL_PROC(_vfs, OID_AUTO, ctl, CTLFLAG_WR, NULL, 0, sysctl_vfs_ctl, "", 4103 "Sysctl by fsid"); 4104 4105 /* 4106 * Function to initialize a va_filerev field sensibly. 4107 * XXX: Wouldn't a random number make a lot more sense ?? 4108 */ 4109 u_quad_t 4110 init_va_filerev(void) 4111 { 4112 struct bintime bt; 4113 4114 getbinuptime(&bt); 4115 return (((u_quad_t)bt.sec << 32LL) | (bt.frac >> 32LL)); 4116 } 4117 4118 static int filt_vfsread(struct knote *kn, long hint); 4119 static int filt_vfswrite(struct knote *kn, long hint); 4120 static int filt_vfsvnode(struct knote *kn, long hint); 4121 static void filt_vfsdetach(struct knote *kn); 4122 static struct filterops vfsread_filtops = { 4123 .f_isfd = 1, 4124 .f_detach = filt_vfsdetach, 4125 .f_event = filt_vfsread 4126 }; 4127 static struct filterops vfswrite_filtops = { 4128 .f_isfd = 1, 4129 .f_detach = filt_vfsdetach, 4130 .f_event = filt_vfswrite 4131 }; 4132 static struct filterops vfsvnode_filtops = { 4133 .f_isfd = 1, 4134 .f_detach = filt_vfsdetach, 4135 .f_event = filt_vfsvnode 4136 }; 4137 4138 static void 4139 vfs_knllock(void *arg) 4140 { 4141 struct vnode *vp = arg; 4142 4143 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 4144 } 4145 4146 static void 4147 vfs_knlunlock(void *arg) 4148 { 4149 struct vnode *vp = arg; 4150 4151 VOP_UNLOCK(vp, 0); 4152 } 4153 4154 static void 4155 vfs_knl_assert_locked(void *arg) 4156 { 4157 #ifdef DEBUG_VFS_LOCKS 4158 struct vnode *vp = arg; 4159 4160 ASSERT_VOP_LOCKED(vp, "vfs_knl_assert_locked"); 4161 #endif 4162 } 4163 4164 static void 4165 vfs_knl_assert_unlocked(void *arg) 4166 { 4167 #ifdef DEBUG_VFS_LOCKS 4168 struct vnode *vp = arg; 4169 4170 ASSERT_VOP_UNLOCKED(vp, "vfs_knl_assert_unlocked"); 4171 #endif 4172 } 4173 4174 int 4175 vfs_kqfilter(struct vop_kqfilter_args *ap) 4176 { 4177 struct vnode *vp = ap->a_vp; 4178 struct knote *kn = ap->a_kn; 4179 struct knlist *knl; 4180 4181 switch (kn->kn_filter) { 4182 case EVFILT_READ: 4183 kn->kn_fop = &vfsread_filtops; 4184 break; 4185 case EVFILT_WRITE: 4186 kn->kn_fop = &vfswrite_filtops; 4187 break; 4188 case EVFILT_VNODE: 4189 kn->kn_fop = &vfsvnode_filtops; 4190 break; 4191 default: 4192 return (EINVAL); 4193 } 4194 4195 kn->kn_hook = (caddr_t)vp; 4196 4197 v_addpollinfo(vp); 4198 if (vp->v_pollinfo == NULL) 4199 return (ENOMEM); 4200 knl = &vp->v_pollinfo->vpi_selinfo.si_note; 4201 knlist_add(knl, kn, 0); 4202 4203 return (0); 4204 } 4205 4206 /* 4207 * Detach knote from vnode 4208 */ 4209 static void 4210 filt_vfsdetach(struct knote *kn) 4211 { 4212 struct vnode *vp = (struct vnode *)kn->kn_hook; 4213 4214 KASSERT(vp->v_pollinfo != NULL, ("Missing v_pollinfo")); 4215 knlist_remove(&vp->v_pollinfo->vpi_selinfo.si_note, kn, 0); 4216 } 4217 4218 /*ARGSUSED*/ 4219 static int 4220 filt_vfsread(struct knote *kn, long hint) 4221 { 4222 struct vnode *vp = (struct vnode *)kn->kn_hook; 4223 struct vattr va; 4224 int res; 4225 4226 /* 4227 * filesystem is gone, so set the EOF flag and schedule 4228 * the knote for deletion. 4229 */ 4230 if (hint == NOTE_REVOKE) { 4231 VI_LOCK(vp); 4232 kn->kn_flags |= (EV_EOF | EV_ONESHOT); 4233 VI_UNLOCK(vp); 4234 return (1); 4235 } 4236 4237 if (VOP_GETATTR(vp, &va, curthread->td_ucred)) 4238 return (0); 4239 4240 VI_LOCK(vp); 4241 kn->kn_data = va.va_size - kn->kn_fp->f_offset; 4242 res = (kn->kn_data != 0); 4243 VI_UNLOCK(vp); 4244 return (res); 4245 } 4246 4247 /*ARGSUSED*/ 4248 static int 4249 filt_vfswrite(struct knote *kn, long hint) 4250 { 4251 struct vnode *vp = (struct vnode *)kn->kn_hook; 4252 4253 VI_LOCK(vp); 4254 4255 /* 4256 * filesystem is gone, so set the EOF flag and schedule 4257 * the knote for deletion. 4258 */ 4259 if (hint == NOTE_REVOKE) 4260 kn->kn_flags |= (EV_EOF | EV_ONESHOT); 4261 4262 kn->kn_data = 0; 4263 VI_UNLOCK(vp); 4264 return (1); 4265 } 4266 4267 static int 4268 filt_vfsvnode(struct knote *kn, long hint) 4269 { 4270 struct vnode *vp = (struct vnode *)kn->kn_hook; 4271 int res; 4272 4273 VI_LOCK(vp); 4274 if (kn->kn_sfflags & hint) 4275 kn->kn_fflags |= hint; 4276 if (hint == NOTE_REVOKE) { 4277 kn->kn_flags |= EV_EOF; 4278 VI_UNLOCK(vp); 4279 return (1); 4280 } 4281 res = (kn->kn_fflags != 0); 4282 VI_UNLOCK(vp); 4283 return (res); 4284 } 4285 4286 int 4287 vfs_read_dirent(struct vop_readdir_args *ap, struct dirent *dp, off_t off) 4288 { 4289 int error; 4290 4291 if (dp->d_reclen > ap->a_uio->uio_resid) 4292 return (ENAMETOOLONG); 4293 error = uiomove(dp, dp->d_reclen, ap->a_uio); 4294 if (error) { 4295 if (ap->a_ncookies != NULL) { 4296 if (ap->a_cookies != NULL) 4297 free(ap->a_cookies, M_TEMP); 4298 ap->a_cookies = NULL; 4299 *ap->a_ncookies = 0; 4300 } 4301 return (error); 4302 } 4303 if (ap->a_ncookies == NULL) 4304 return (0); 4305 4306 KASSERT(ap->a_cookies, 4307 ("NULL ap->a_cookies value with non-NULL ap->a_ncookies!")); 4308 4309 *ap->a_cookies = realloc(*ap->a_cookies, 4310 (*ap->a_ncookies + 1) * sizeof(u_long), M_TEMP, M_WAITOK | M_ZERO); 4311 (*ap->a_cookies)[*ap->a_ncookies] = off; 4312 return (0); 4313 } 4314 4315 /* 4316 * Mark for update the access time of the file if the filesystem 4317 * supports VOP_MARKATIME. This functionality is used by execve and 4318 * mmap, so we want to avoid the I/O implied by directly setting 4319 * va_atime for the sake of efficiency. 4320 */ 4321 void 4322 vfs_mark_atime(struct vnode *vp, struct ucred *cred) 4323 { 4324 struct mount *mp; 4325 4326 mp = vp->v_mount; 4327 VFS_ASSERT_GIANT(mp); 4328 ASSERT_VOP_LOCKED(vp, "vfs_mark_atime"); 4329 if (mp != NULL && (mp->mnt_flag & (MNT_NOATIME | MNT_RDONLY)) == 0) 4330 (void)VOP_MARKATIME(vp); 4331 } 4332 4333 /* 4334 * The purpose of this routine is to remove granularity from accmode_t, 4335 * reducing it into standard unix access bits - VEXEC, VREAD, VWRITE, 4336 * VADMIN and VAPPEND. 4337 * 4338 * If it returns 0, the caller is supposed to continue with the usual 4339 * access checks using 'accmode' as modified by this routine. If it 4340 * returns nonzero value, the caller is supposed to return that value 4341 * as errno. 4342 * 4343 * Note that after this routine runs, accmode may be zero. 4344 */ 4345 int 4346 vfs_unixify_accmode(accmode_t *accmode) 4347 { 4348 /* 4349 * There is no way to specify explicit "deny" rule using 4350 * file mode or POSIX.1e ACLs. 4351 */ 4352 if (*accmode & VEXPLICIT_DENY) { 4353 *accmode = 0; 4354 return (0); 4355 } 4356 4357 /* 4358 * None of these can be translated into usual access bits. 4359 * Also, the common case for NFSv4 ACLs is to not contain 4360 * either of these bits. Caller should check for VWRITE 4361 * on the containing directory instead. 4362 */ 4363 if (*accmode & (VDELETE_CHILD | VDELETE)) 4364 return (EPERM); 4365 4366 if (*accmode & VADMIN_PERMS) { 4367 *accmode &= ~VADMIN_PERMS; 4368 *accmode |= VADMIN; 4369 } 4370 4371 /* 4372 * There is no way to deny VREAD_ATTRIBUTES, VREAD_ACL 4373 * or VSYNCHRONIZE using file mode or POSIX.1e ACL. 4374 */ 4375 *accmode &= ~(VSTAT_PERMS | VSYNCHRONIZE); 4376 4377 return (0); 4378 } 4379