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