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 BO_LOCK(bo); 1264 bremfree(bp); 1265 BO_UNLOCK(bo); 1266 bp->b_flags |= B_ASYNC; 1267 bwrite(bp); 1268 BO_LOCK(bo); 1269 return (EAGAIN); /* XXX: why not loop ? */ 1270 } 1271 BO_LOCK(bo); 1272 bremfree(bp); 1273 BO_UNLOCK(bo); 1274 bp->b_flags |= (B_INVAL | B_RELBUF); 1275 bp->b_flags &= ~B_ASYNC; 1276 brelse(bp); 1277 BO_LOCK(bo); 1278 if (nbp != NULL && 1279 (nbp->b_bufobj != bo || 1280 nbp->b_lblkno != lblkno || 1281 (nbp->b_xflags & 1282 (BX_BKGRDMARKER | BX_VNDIRTY | BX_VNCLEAN)) != xflags)) 1283 break; /* nbp invalid */ 1284 } 1285 return (retval); 1286 } 1287 1288 /* 1289 * Truncate a file's buffer and pages to a specified length. This 1290 * is in lieu of the old vinvalbuf mechanism, which performed unneeded 1291 * sync activity. 1292 */ 1293 int 1294 vtruncbuf(struct vnode *vp, struct ucred *cred, struct thread *td, 1295 off_t length, int blksize) 1296 { 1297 struct buf *bp, *nbp; 1298 int anyfreed; 1299 int trunclbn; 1300 struct bufobj *bo; 1301 1302 CTR5(KTR_VFS, "%s: vp %p with cred %p and block %d:%ju", __func__, 1303 vp, cred, blksize, (uintmax_t)length); 1304 1305 /* 1306 * Round up to the *next* lbn. 1307 */ 1308 trunclbn = (length + blksize - 1) / blksize; 1309 1310 ASSERT_VOP_LOCKED(vp, "vtruncbuf"); 1311 restart: 1312 bo = &vp->v_bufobj; 1313 BO_LOCK(bo); 1314 anyfreed = 1; 1315 for (;anyfreed;) { 1316 anyfreed = 0; 1317 TAILQ_FOREACH_SAFE(bp, &bo->bo_clean.bv_hd, b_bobufs, nbp) { 1318 if (bp->b_lblkno < trunclbn) 1319 continue; 1320 if (BUF_LOCK(bp, 1321 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, 1322 BO_MTX(bo)) == ENOLCK) 1323 goto restart; 1324 1325 BO_LOCK(bo); 1326 bremfree(bp); 1327 BO_UNLOCK(bo); 1328 bp->b_flags |= (B_INVAL | B_RELBUF); 1329 bp->b_flags &= ~B_ASYNC; 1330 brelse(bp); 1331 anyfreed = 1; 1332 1333 if (nbp != NULL && 1334 (((nbp->b_xflags & BX_VNCLEAN) == 0) || 1335 (nbp->b_vp != vp) || 1336 (nbp->b_flags & B_DELWRI))) { 1337 goto restart; 1338 } 1339 BO_LOCK(bo); 1340 } 1341 1342 TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) { 1343 if (bp->b_lblkno < trunclbn) 1344 continue; 1345 if (BUF_LOCK(bp, 1346 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, 1347 BO_MTX(bo)) == ENOLCK) 1348 goto restart; 1349 BO_LOCK(bo); 1350 bremfree(bp); 1351 BO_UNLOCK(bo); 1352 bp->b_flags |= (B_INVAL | B_RELBUF); 1353 bp->b_flags &= ~B_ASYNC; 1354 brelse(bp); 1355 anyfreed = 1; 1356 if (nbp != NULL && 1357 (((nbp->b_xflags & BX_VNDIRTY) == 0) || 1358 (nbp->b_vp != vp) || 1359 (nbp->b_flags & B_DELWRI) == 0)) { 1360 goto restart; 1361 } 1362 BO_LOCK(bo); 1363 } 1364 } 1365 1366 if (length > 0) { 1367 restartsync: 1368 TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) { 1369 if (bp->b_lblkno > 0) 1370 continue; 1371 /* 1372 * Since we hold the vnode lock this should only 1373 * fail if we're racing with the buf daemon. 1374 */ 1375 if (BUF_LOCK(bp, 1376 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, 1377 BO_MTX(bo)) == ENOLCK) { 1378 goto restart; 1379 } 1380 VNASSERT((bp->b_flags & B_DELWRI), vp, 1381 ("buf(%p) on dirty queue without DELWRI", bp)); 1382 1383 BO_LOCK(bo); 1384 bremfree(bp); 1385 BO_UNLOCK(bo); 1386 bawrite(bp); 1387 BO_LOCK(bo); 1388 goto restartsync; 1389 } 1390 } 1391 1392 bufobj_wwait(bo, 0, 0); 1393 BO_UNLOCK(bo); 1394 vnode_pager_setsize(vp, length); 1395 1396 return (0); 1397 } 1398 1399 /* 1400 * buf_splay() - splay tree core for the clean/dirty list of buffers in 1401 * a vnode. 1402 * 1403 * NOTE: We have to deal with the special case of a background bitmap 1404 * buffer, a situation where two buffers will have the same logical 1405 * block offset. We want (1) only the foreground buffer to be accessed 1406 * in a lookup and (2) must differentiate between the foreground and 1407 * background buffer in the splay tree algorithm because the splay 1408 * tree cannot normally handle multiple entities with the same 'index'. 1409 * We accomplish this by adding differentiating flags to the splay tree's 1410 * numerical domain. 1411 */ 1412 static 1413 struct buf * 1414 buf_splay(daddr_t lblkno, b_xflags_t xflags, struct buf *root) 1415 { 1416 struct buf dummy; 1417 struct buf *lefttreemax, *righttreemin, *y; 1418 1419 if (root == NULL) 1420 return (NULL); 1421 lefttreemax = righttreemin = &dummy; 1422 for (;;) { 1423 if (lblkno < root->b_lblkno || 1424 (lblkno == root->b_lblkno && 1425 (xflags & BX_BKGRDMARKER) < (root->b_xflags & BX_BKGRDMARKER))) { 1426 if ((y = root->b_left) == NULL) 1427 break; 1428 if (lblkno < y->b_lblkno) { 1429 /* Rotate right. */ 1430 root->b_left = y->b_right; 1431 y->b_right = root; 1432 root = y; 1433 if ((y = root->b_left) == NULL) 1434 break; 1435 } 1436 /* Link into the new root's right tree. */ 1437 righttreemin->b_left = root; 1438 righttreemin = root; 1439 } else if (lblkno > root->b_lblkno || 1440 (lblkno == root->b_lblkno && 1441 (xflags & BX_BKGRDMARKER) > (root->b_xflags & BX_BKGRDMARKER))) { 1442 if ((y = root->b_right) == NULL) 1443 break; 1444 if (lblkno > y->b_lblkno) { 1445 /* Rotate left. */ 1446 root->b_right = y->b_left; 1447 y->b_left = root; 1448 root = y; 1449 if ((y = root->b_right) == NULL) 1450 break; 1451 } 1452 /* Link into the new root's left tree. */ 1453 lefttreemax->b_right = root; 1454 lefttreemax = root; 1455 } else { 1456 break; 1457 } 1458 root = y; 1459 } 1460 /* Assemble the new root. */ 1461 lefttreemax->b_right = root->b_left; 1462 righttreemin->b_left = root->b_right; 1463 root->b_left = dummy.b_right; 1464 root->b_right = dummy.b_left; 1465 return (root); 1466 } 1467 1468 static void 1469 buf_vlist_remove(struct buf *bp) 1470 { 1471 struct buf *root; 1472 struct bufv *bv; 1473 1474 KASSERT(bp->b_bufobj != NULL, ("No b_bufobj %p", bp)); 1475 ASSERT_BO_LOCKED(bp->b_bufobj); 1476 KASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) != 1477 (BX_VNDIRTY|BX_VNCLEAN), 1478 ("buf_vlist_remove: Buf %p is on two lists", bp)); 1479 if (bp->b_xflags & BX_VNDIRTY) 1480 bv = &bp->b_bufobj->bo_dirty; 1481 else 1482 bv = &bp->b_bufobj->bo_clean; 1483 if (bp != bv->bv_root) { 1484 root = buf_splay(bp->b_lblkno, bp->b_xflags, bv->bv_root); 1485 KASSERT(root == bp, ("splay lookup failed in remove")); 1486 } 1487 if (bp->b_left == NULL) { 1488 root = bp->b_right; 1489 } else { 1490 root = buf_splay(bp->b_lblkno, bp->b_xflags, bp->b_left); 1491 root->b_right = bp->b_right; 1492 } 1493 bv->bv_root = root; 1494 TAILQ_REMOVE(&bv->bv_hd, bp, b_bobufs); 1495 bv->bv_cnt--; 1496 bp->b_xflags &= ~(BX_VNDIRTY | BX_VNCLEAN); 1497 } 1498 1499 /* 1500 * Add the buffer to the sorted clean or dirty block list using a 1501 * splay tree algorithm. 1502 * 1503 * NOTE: xflags is passed as a constant, optimizing this inline function! 1504 */ 1505 static void 1506 buf_vlist_add(struct buf *bp, struct bufobj *bo, b_xflags_t xflags) 1507 { 1508 struct buf *root; 1509 struct bufv *bv; 1510 1511 ASSERT_BO_LOCKED(bo); 1512 KASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) == 0, 1513 ("buf_vlist_add: Buf %p has existing xflags %d", bp, bp->b_xflags)); 1514 bp->b_xflags |= xflags; 1515 if (xflags & BX_VNDIRTY) 1516 bv = &bo->bo_dirty; 1517 else 1518 bv = &bo->bo_clean; 1519 1520 root = buf_splay(bp->b_lblkno, bp->b_xflags, bv->bv_root); 1521 if (root == NULL) { 1522 bp->b_left = NULL; 1523 bp->b_right = NULL; 1524 TAILQ_INSERT_TAIL(&bv->bv_hd, bp, b_bobufs); 1525 } else if (bp->b_lblkno < root->b_lblkno || 1526 (bp->b_lblkno == root->b_lblkno && 1527 (bp->b_xflags & BX_BKGRDMARKER) < (root->b_xflags & BX_BKGRDMARKER))) { 1528 bp->b_left = root->b_left; 1529 bp->b_right = root; 1530 root->b_left = NULL; 1531 TAILQ_INSERT_BEFORE(root, bp, b_bobufs); 1532 } else { 1533 bp->b_right = root->b_right; 1534 bp->b_left = root; 1535 root->b_right = NULL; 1536 TAILQ_INSERT_AFTER(&bv->bv_hd, root, bp, b_bobufs); 1537 } 1538 bv->bv_cnt++; 1539 bv->bv_root = bp; 1540 } 1541 1542 /* 1543 * Lookup a buffer using the splay tree. Note that we specifically avoid 1544 * shadow buffers used in background bitmap writes. 1545 * 1546 * This code isn't quite efficient as it could be because we are maintaining 1547 * two sorted lists and do not know which list the block resides in. 1548 * 1549 * During a "make buildworld" the desired buffer is found at one of 1550 * the roots more than 60% of the time. Thus, checking both roots 1551 * before performing either splay eliminates unnecessary splays on the 1552 * first tree splayed. 1553 */ 1554 struct buf * 1555 gbincore(struct bufobj *bo, daddr_t lblkno) 1556 { 1557 struct buf *bp; 1558 1559 ASSERT_BO_LOCKED(bo); 1560 if ((bp = bo->bo_clean.bv_root) != NULL && 1561 bp->b_lblkno == lblkno && !(bp->b_xflags & BX_BKGRDMARKER)) 1562 return (bp); 1563 if ((bp = bo->bo_dirty.bv_root) != NULL && 1564 bp->b_lblkno == lblkno && !(bp->b_xflags & BX_BKGRDMARKER)) 1565 return (bp); 1566 if ((bp = bo->bo_clean.bv_root) != NULL) { 1567 bo->bo_clean.bv_root = bp = buf_splay(lblkno, 0, bp); 1568 if (bp->b_lblkno == lblkno && !(bp->b_xflags & BX_BKGRDMARKER)) 1569 return (bp); 1570 } 1571 if ((bp = bo->bo_dirty.bv_root) != NULL) { 1572 bo->bo_dirty.bv_root = bp = buf_splay(lblkno, 0, bp); 1573 if (bp->b_lblkno == lblkno && !(bp->b_xflags & BX_BKGRDMARKER)) 1574 return (bp); 1575 } 1576 return (NULL); 1577 } 1578 1579 /* 1580 * Associate a buffer with a vnode. 1581 */ 1582 void 1583 bgetvp(struct vnode *vp, struct buf *bp) 1584 { 1585 struct bufobj *bo; 1586 1587 bo = &vp->v_bufobj; 1588 ASSERT_BO_LOCKED(bo); 1589 VNASSERT(bp->b_vp == NULL, bp->b_vp, ("bgetvp: not free")); 1590 1591 CTR3(KTR_BUF, "bgetvp(%p) vp %p flags %X", bp, vp, bp->b_flags); 1592 VNASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) == 0, vp, 1593 ("bgetvp: bp already attached! %p", bp)); 1594 1595 vhold(vp); 1596 if (VFS_NEEDSGIANT(vp->v_mount) || bo->bo_flag & BO_NEEDSGIANT) 1597 bp->b_flags |= B_NEEDSGIANT; 1598 bp->b_vp = vp; 1599 bp->b_bufobj = bo; 1600 /* 1601 * Insert onto list for new vnode. 1602 */ 1603 buf_vlist_add(bp, bo, BX_VNCLEAN); 1604 } 1605 1606 /* 1607 * Disassociate a buffer from a vnode. 1608 */ 1609 void 1610 brelvp(struct buf *bp) 1611 { 1612 struct bufobj *bo; 1613 struct vnode *vp; 1614 1615 CTR3(KTR_BUF, "brelvp(%p) vp %p flags %X", bp, bp->b_vp, bp->b_flags); 1616 KASSERT(bp->b_vp != NULL, ("brelvp: NULL")); 1617 1618 /* 1619 * Delete from old vnode list, if on one. 1620 */ 1621 vp = bp->b_vp; /* XXX */ 1622 bo = bp->b_bufobj; 1623 BO_LOCK(bo); 1624 if (bp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN)) 1625 buf_vlist_remove(bp); 1626 else 1627 panic("brelvp: Buffer %p not on queue.", bp); 1628 if ((bo->bo_flag & BO_ONWORKLST) && bo->bo_dirty.bv_cnt == 0) { 1629 bo->bo_flag &= ~BO_ONWORKLST; 1630 mtx_lock(&sync_mtx); 1631 LIST_REMOVE(bo, bo_synclist); 1632 syncer_worklist_len--; 1633 mtx_unlock(&sync_mtx); 1634 } 1635 bp->b_flags &= ~B_NEEDSGIANT; 1636 bp->b_vp = NULL; 1637 bp->b_bufobj = NULL; 1638 BO_UNLOCK(bo); 1639 vdrop(vp); 1640 } 1641 1642 /* 1643 * Add an item to the syncer work queue. 1644 */ 1645 static void 1646 vn_syncer_add_to_worklist(struct bufobj *bo, int delay) 1647 { 1648 int queue, slot; 1649 1650 ASSERT_BO_LOCKED(bo); 1651 1652 mtx_lock(&sync_mtx); 1653 if (bo->bo_flag & BO_ONWORKLST) 1654 LIST_REMOVE(bo, bo_synclist); 1655 else { 1656 bo->bo_flag |= BO_ONWORKLST; 1657 syncer_worklist_len++; 1658 } 1659 1660 if (delay > syncer_maxdelay - 2) 1661 delay = syncer_maxdelay - 2; 1662 slot = (syncer_delayno + delay) & syncer_mask; 1663 1664 queue = VFS_NEEDSGIANT(bo->__bo_vnode->v_mount) ? WI_GIANTQ : 1665 WI_MPSAFEQ; 1666 LIST_INSERT_HEAD(&syncer_workitem_pending[queue][slot], bo, 1667 bo_synclist); 1668 mtx_unlock(&sync_mtx); 1669 } 1670 1671 static int 1672 sysctl_vfs_worklist_len(SYSCTL_HANDLER_ARGS) 1673 { 1674 int error, len; 1675 1676 mtx_lock(&sync_mtx); 1677 len = syncer_worklist_len - sync_vnode_count; 1678 mtx_unlock(&sync_mtx); 1679 error = SYSCTL_OUT(req, &len, sizeof(len)); 1680 return (error); 1681 } 1682 1683 SYSCTL_PROC(_vfs, OID_AUTO, worklist_len, CTLTYPE_INT | CTLFLAG_RD, NULL, 0, 1684 sysctl_vfs_worklist_len, "I", "Syncer thread worklist length"); 1685 1686 static struct proc *updateproc; 1687 static void sched_sync(void); 1688 static struct kproc_desc up_kp = { 1689 "syncer", 1690 sched_sync, 1691 &updateproc 1692 }; 1693 SYSINIT(syncer, SI_SUB_KTHREAD_UPDATE, SI_ORDER_FIRST, kproc_start, &up_kp); 1694 1695 static int 1696 sync_vnode(struct synclist *slp, struct bufobj **bo, struct thread *td) 1697 { 1698 struct vnode *vp; 1699 struct mount *mp; 1700 1701 *bo = LIST_FIRST(slp); 1702 if (*bo == NULL) 1703 return (0); 1704 vp = (*bo)->__bo_vnode; /* XXX */ 1705 if (VOP_ISLOCKED(vp) != 0 || VI_TRYLOCK(vp) == 0) 1706 return (1); 1707 /* 1708 * We use vhold in case the vnode does not 1709 * successfully sync. vhold prevents the vnode from 1710 * going away when we unlock the sync_mtx so that 1711 * we can acquire the vnode interlock. 1712 */ 1713 vholdl(vp); 1714 mtx_unlock(&sync_mtx); 1715 VI_UNLOCK(vp); 1716 if (vn_start_write(vp, &mp, V_NOWAIT) != 0) { 1717 vdrop(vp); 1718 mtx_lock(&sync_mtx); 1719 return (*bo == LIST_FIRST(slp)); 1720 } 1721 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 1722 (void) VOP_FSYNC(vp, MNT_LAZY, td); 1723 VOP_UNLOCK(vp, 0); 1724 vn_finished_write(mp); 1725 BO_LOCK(*bo); 1726 if (((*bo)->bo_flag & BO_ONWORKLST) != 0) { 1727 /* 1728 * Put us back on the worklist. The worklist 1729 * routine will remove us from our current 1730 * position and then add us back in at a later 1731 * position. 1732 */ 1733 vn_syncer_add_to_worklist(*bo, syncdelay); 1734 } 1735 BO_UNLOCK(*bo); 1736 vdrop(vp); 1737 mtx_lock(&sync_mtx); 1738 return (0); 1739 } 1740 1741 /* 1742 * System filesystem synchronizer daemon. 1743 */ 1744 static void 1745 sched_sync(void) 1746 { 1747 struct synclist *gnext, *next; 1748 struct synclist *gslp, *slp; 1749 struct bufobj *bo; 1750 long starttime; 1751 struct thread *td = curthread; 1752 int last_work_seen; 1753 int net_worklist_len; 1754 int syncer_final_iter; 1755 int first_printf; 1756 int error; 1757 1758 last_work_seen = 0; 1759 syncer_final_iter = 0; 1760 first_printf = 1; 1761 syncer_state = SYNCER_RUNNING; 1762 starttime = time_uptime; 1763 td->td_pflags |= TDP_NORUNNINGBUF; 1764 1765 EVENTHANDLER_REGISTER(shutdown_pre_sync, syncer_shutdown, td->td_proc, 1766 SHUTDOWN_PRI_LAST); 1767 1768 mtx_lock(&sync_mtx); 1769 for (;;) { 1770 if (syncer_state == SYNCER_FINAL_DELAY && 1771 syncer_final_iter == 0) { 1772 mtx_unlock(&sync_mtx); 1773 kproc_suspend_check(td->td_proc); 1774 mtx_lock(&sync_mtx); 1775 } 1776 net_worklist_len = syncer_worklist_len - sync_vnode_count; 1777 if (syncer_state != SYNCER_RUNNING && 1778 starttime != time_uptime) { 1779 if (first_printf) { 1780 printf("\nSyncing disks, vnodes remaining..."); 1781 first_printf = 0; 1782 } 1783 printf("%d ", net_worklist_len); 1784 } 1785 starttime = time_uptime; 1786 1787 /* 1788 * Push files whose dirty time has expired. Be careful 1789 * of interrupt race on slp queue. 1790 * 1791 * Skip over empty worklist slots when shutting down. 1792 */ 1793 do { 1794 slp = &syncer_workitem_pending[WI_MPSAFEQ][syncer_delayno]; 1795 gslp = &syncer_workitem_pending[WI_GIANTQ][syncer_delayno]; 1796 syncer_delayno += 1; 1797 if (syncer_delayno == syncer_maxdelay) 1798 syncer_delayno = 0; 1799 next = &syncer_workitem_pending[WI_MPSAFEQ][syncer_delayno]; 1800 gnext = &syncer_workitem_pending[WI_GIANTQ][syncer_delayno]; 1801 /* 1802 * If the worklist has wrapped since the 1803 * it was emptied of all but syncer vnodes, 1804 * switch to the FINAL_DELAY state and run 1805 * for one more second. 1806 */ 1807 if (syncer_state == SYNCER_SHUTTING_DOWN && 1808 net_worklist_len == 0 && 1809 last_work_seen == syncer_delayno) { 1810 syncer_state = SYNCER_FINAL_DELAY; 1811 syncer_final_iter = SYNCER_SHUTDOWN_SPEEDUP; 1812 } 1813 } while (syncer_state != SYNCER_RUNNING && LIST_EMPTY(slp) && 1814 LIST_EMPTY(gslp) && syncer_worklist_len > 0); 1815 1816 /* 1817 * Keep track of the last time there was anything 1818 * on the worklist other than syncer vnodes. 1819 * Return to the SHUTTING_DOWN state if any 1820 * new work appears. 1821 */ 1822 if (net_worklist_len > 0 || syncer_state == SYNCER_RUNNING) 1823 last_work_seen = syncer_delayno; 1824 if (net_worklist_len > 0 && syncer_state == SYNCER_FINAL_DELAY) 1825 syncer_state = SYNCER_SHUTTING_DOWN; 1826 while (!LIST_EMPTY(slp)) { 1827 error = sync_vnode(slp, &bo, td); 1828 if (error == 1) { 1829 LIST_REMOVE(bo, bo_synclist); 1830 LIST_INSERT_HEAD(next, bo, bo_synclist); 1831 continue; 1832 } 1833 } 1834 if (!LIST_EMPTY(gslp)) { 1835 mtx_unlock(&sync_mtx); 1836 mtx_lock(&Giant); 1837 mtx_lock(&sync_mtx); 1838 while (!LIST_EMPTY(gslp)) { 1839 error = sync_vnode(gslp, &bo, td); 1840 if (error == 1) { 1841 LIST_REMOVE(bo, bo_synclist); 1842 LIST_INSERT_HEAD(gnext, bo, 1843 bo_synclist); 1844 continue; 1845 } 1846 } 1847 mtx_unlock(&Giant); 1848 } 1849 if (syncer_state == SYNCER_FINAL_DELAY && syncer_final_iter > 0) 1850 syncer_final_iter--; 1851 /* 1852 * The variable rushjob allows the kernel to speed up the 1853 * processing of the filesystem syncer process. A rushjob 1854 * value of N tells the filesystem syncer to process the next 1855 * N seconds worth of work on its queue ASAP. Currently rushjob 1856 * is used by the soft update code to speed up the filesystem 1857 * syncer process when the incore state is getting so far 1858 * ahead of the disk that the kernel memory pool is being 1859 * threatened with exhaustion. 1860 */ 1861 if (rushjob > 0) { 1862 rushjob -= 1; 1863 continue; 1864 } 1865 /* 1866 * Just sleep for a short period of time between 1867 * iterations when shutting down to allow some I/O 1868 * to happen. 1869 * 1870 * If it has taken us less than a second to process the 1871 * current work, then wait. Otherwise start right over 1872 * again. We can still lose time if any single round 1873 * takes more than two seconds, but it does not really 1874 * matter as we are just trying to generally pace the 1875 * filesystem activity. 1876 */ 1877 if (syncer_state != SYNCER_RUNNING) 1878 cv_timedwait(&sync_wakeup, &sync_mtx, 1879 hz / SYNCER_SHUTDOWN_SPEEDUP); 1880 else if (time_uptime == starttime) 1881 cv_timedwait(&sync_wakeup, &sync_mtx, hz); 1882 } 1883 } 1884 1885 /* 1886 * Request the syncer daemon to speed up its work. 1887 * We never push it to speed up more than half of its 1888 * normal turn time, otherwise it could take over the cpu. 1889 */ 1890 int 1891 speedup_syncer(void) 1892 { 1893 int ret = 0; 1894 1895 mtx_lock(&sync_mtx); 1896 if (rushjob < syncdelay / 2) { 1897 rushjob += 1; 1898 stat_rush_requests += 1; 1899 ret = 1; 1900 } 1901 mtx_unlock(&sync_mtx); 1902 cv_broadcast(&sync_wakeup); 1903 return (ret); 1904 } 1905 1906 /* 1907 * Tell the syncer to speed up its work and run though its work 1908 * list several times, then tell it to shut down. 1909 */ 1910 static void 1911 syncer_shutdown(void *arg, int howto) 1912 { 1913 1914 if (howto & RB_NOSYNC) 1915 return; 1916 mtx_lock(&sync_mtx); 1917 syncer_state = SYNCER_SHUTTING_DOWN; 1918 rushjob = 0; 1919 mtx_unlock(&sync_mtx); 1920 cv_broadcast(&sync_wakeup); 1921 kproc_shutdown(arg, howto); 1922 } 1923 1924 /* 1925 * Reassign a buffer from one vnode to another. 1926 * Used to assign file specific control information 1927 * (indirect blocks) to the vnode to which they belong. 1928 */ 1929 void 1930 reassignbuf(struct buf *bp) 1931 { 1932 struct vnode *vp; 1933 struct bufobj *bo; 1934 int delay; 1935 #ifdef INVARIANTS 1936 struct bufv *bv; 1937 #endif 1938 1939 vp = bp->b_vp; 1940 bo = bp->b_bufobj; 1941 ++reassignbufcalls; 1942 1943 CTR3(KTR_BUF, "reassignbuf(%p) vp %p flags %X", 1944 bp, bp->b_vp, bp->b_flags); 1945 /* 1946 * B_PAGING flagged buffers cannot be reassigned because their vp 1947 * is not fully linked in. 1948 */ 1949 if (bp->b_flags & B_PAGING) 1950 panic("cannot reassign paging buffer"); 1951 1952 /* 1953 * Delete from old vnode list, if on one. 1954 */ 1955 BO_LOCK(bo); 1956 if (bp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN)) 1957 buf_vlist_remove(bp); 1958 else 1959 panic("reassignbuf: Buffer %p not on queue.", bp); 1960 /* 1961 * If dirty, put on list of dirty buffers; otherwise insert onto list 1962 * of clean buffers. 1963 */ 1964 if (bp->b_flags & B_DELWRI) { 1965 if ((bo->bo_flag & BO_ONWORKLST) == 0) { 1966 switch (vp->v_type) { 1967 case VDIR: 1968 delay = dirdelay; 1969 break; 1970 case VCHR: 1971 delay = metadelay; 1972 break; 1973 default: 1974 delay = filedelay; 1975 } 1976 vn_syncer_add_to_worklist(bo, delay); 1977 } 1978 buf_vlist_add(bp, bo, BX_VNDIRTY); 1979 } else { 1980 buf_vlist_add(bp, bo, BX_VNCLEAN); 1981 1982 if ((bo->bo_flag & BO_ONWORKLST) && bo->bo_dirty.bv_cnt == 0) { 1983 mtx_lock(&sync_mtx); 1984 LIST_REMOVE(bo, bo_synclist); 1985 syncer_worklist_len--; 1986 mtx_unlock(&sync_mtx); 1987 bo->bo_flag &= ~BO_ONWORKLST; 1988 } 1989 } 1990 #ifdef INVARIANTS 1991 bv = &bo->bo_clean; 1992 bp = TAILQ_FIRST(&bv->bv_hd); 1993 KASSERT(bp == NULL || bp->b_bufobj == bo, 1994 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 1995 bp = TAILQ_LAST(&bv->bv_hd, buflists); 1996 KASSERT(bp == NULL || bp->b_bufobj == bo, 1997 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 1998 bv = &bo->bo_dirty; 1999 bp = TAILQ_FIRST(&bv->bv_hd); 2000 KASSERT(bp == NULL || bp->b_bufobj == bo, 2001 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 2002 bp = TAILQ_LAST(&bv->bv_hd, buflists); 2003 KASSERT(bp == NULL || bp->b_bufobj == bo, 2004 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 2005 #endif 2006 BO_UNLOCK(bo); 2007 } 2008 2009 /* 2010 * Increment the use and hold counts on the vnode, taking care to reference 2011 * the driver's usecount if this is a chardev. The vholdl() will remove 2012 * the vnode from the free list if it is presently free. Requires the 2013 * vnode interlock and returns with it held. 2014 */ 2015 static void 2016 v_incr_usecount(struct vnode *vp) 2017 { 2018 2019 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2020 vp->v_usecount++; 2021 if (vp->v_type == VCHR && vp->v_rdev != NULL) { 2022 dev_lock(); 2023 vp->v_rdev->si_usecount++; 2024 dev_unlock(); 2025 } 2026 vholdl(vp); 2027 } 2028 2029 /* 2030 * Turn a holdcnt into a use+holdcnt such that only one call to 2031 * v_decr_usecount is needed. 2032 */ 2033 static void 2034 v_upgrade_usecount(struct vnode *vp) 2035 { 2036 2037 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2038 vp->v_usecount++; 2039 if (vp->v_type == VCHR && vp->v_rdev != NULL) { 2040 dev_lock(); 2041 vp->v_rdev->si_usecount++; 2042 dev_unlock(); 2043 } 2044 } 2045 2046 /* 2047 * Decrement the vnode use and hold count along with the driver's usecount 2048 * if this is a chardev. The vdropl() below releases the vnode interlock 2049 * as it may free the vnode. 2050 */ 2051 static void 2052 v_decr_usecount(struct vnode *vp) 2053 { 2054 2055 ASSERT_VI_LOCKED(vp, __FUNCTION__); 2056 VNASSERT(vp->v_usecount > 0, vp, 2057 ("v_decr_usecount: negative usecount")); 2058 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2059 vp->v_usecount--; 2060 if (vp->v_type == VCHR && vp->v_rdev != NULL) { 2061 dev_lock(); 2062 vp->v_rdev->si_usecount--; 2063 dev_unlock(); 2064 } 2065 vdropl(vp); 2066 } 2067 2068 /* 2069 * Decrement only the use count and driver use count. This is intended to 2070 * be paired with a follow on vdropl() to release the remaining hold count. 2071 * In this way we may vgone() a vnode with a 0 usecount without risk of 2072 * having it end up on a free list because the hold count is kept above 0. 2073 */ 2074 static void 2075 v_decr_useonly(struct vnode *vp) 2076 { 2077 2078 ASSERT_VI_LOCKED(vp, __FUNCTION__); 2079 VNASSERT(vp->v_usecount > 0, vp, 2080 ("v_decr_useonly: negative usecount")); 2081 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2082 vp->v_usecount--; 2083 if (vp->v_type == VCHR && vp->v_rdev != NULL) { 2084 dev_lock(); 2085 vp->v_rdev->si_usecount--; 2086 dev_unlock(); 2087 } 2088 } 2089 2090 /* 2091 * Grab a particular vnode from the free list, increment its 2092 * reference count and lock it. VI_DOOMED is set if the vnode 2093 * is being destroyed. Only callers who specify LK_RETRY will 2094 * see doomed vnodes. If inactive processing was delayed in 2095 * vput try to do it here. 2096 */ 2097 int 2098 vget(struct vnode *vp, int flags, struct thread *td) 2099 { 2100 int error; 2101 2102 error = 0; 2103 VFS_ASSERT_GIANT(vp->v_mount); 2104 VNASSERT((flags & LK_TYPE_MASK) != 0, vp, 2105 ("vget: invalid lock operation")); 2106 CTR3(KTR_VFS, "%s: vp %p with flags %d", __func__, vp, flags); 2107 2108 if ((flags & LK_INTERLOCK) == 0) 2109 VI_LOCK(vp); 2110 vholdl(vp); 2111 if ((error = vn_lock(vp, flags | LK_INTERLOCK)) != 0) { 2112 vdrop(vp); 2113 CTR2(KTR_VFS, "%s: impossible to lock vnode %p", __func__, 2114 vp); 2115 return (error); 2116 } 2117 if (vp->v_iflag & VI_DOOMED && (flags & LK_RETRY) == 0) 2118 panic("vget: vn_lock failed to return ENOENT\n"); 2119 VI_LOCK(vp); 2120 /* Upgrade our holdcnt to a usecount. */ 2121 v_upgrade_usecount(vp); 2122 /* 2123 * We don't guarantee that any particular close will 2124 * trigger inactive processing so just make a best effort 2125 * here at preventing a reference to a removed file. If 2126 * we don't succeed no harm is done. 2127 */ 2128 if (vp->v_iflag & VI_OWEINACT) { 2129 if (VOP_ISLOCKED(vp) == LK_EXCLUSIVE && 2130 (flags & LK_NOWAIT) == 0) 2131 vinactive(vp, td); 2132 vp->v_iflag &= ~VI_OWEINACT; 2133 } 2134 VI_UNLOCK(vp); 2135 return (0); 2136 } 2137 2138 /* 2139 * Increase the reference count of a vnode. 2140 */ 2141 void 2142 vref(struct vnode *vp) 2143 { 2144 2145 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2146 VI_LOCK(vp); 2147 v_incr_usecount(vp); 2148 VI_UNLOCK(vp); 2149 } 2150 2151 /* 2152 * Return reference count of a vnode. 2153 * 2154 * The results of this call are only guaranteed when some mechanism other 2155 * than the VI lock is used to stop other processes from gaining references 2156 * to the vnode. This may be the case if the caller holds the only reference. 2157 * This is also useful when stale data is acceptable as race conditions may 2158 * be accounted for by some other means. 2159 */ 2160 int 2161 vrefcnt(struct vnode *vp) 2162 { 2163 int usecnt; 2164 2165 VI_LOCK(vp); 2166 usecnt = vp->v_usecount; 2167 VI_UNLOCK(vp); 2168 2169 return (usecnt); 2170 } 2171 2172 #define VPUTX_VRELE 1 2173 #define VPUTX_VPUT 2 2174 #define VPUTX_VUNREF 3 2175 2176 static void 2177 vputx(struct vnode *vp, int func) 2178 { 2179 int error; 2180 2181 KASSERT(vp != NULL, ("vputx: null vp")); 2182 if (func == VPUTX_VUNREF) 2183 ASSERT_VOP_ELOCKED(vp, "vunref"); 2184 else if (func == VPUTX_VPUT) 2185 ASSERT_VOP_LOCKED(vp, "vput"); 2186 else 2187 KASSERT(func == VPUTX_VRELE, ("vputx: wrong func")); 2188 VFS_ASSERT_GIANT(vp->v_mount); 2189 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2190 VI_LOCK(vp); 2191 2192 /* Skip this v_writecount check if we're going to panic below. */ 2193 VNASSERT(vp->v_writecount < vp->v_usecount || vp->v_usecount < 1, vp, 2194 ("vputx: missed vn_close")); 2195 error = 0; 2196 2197 if (vp->v_usecount > 1 || ((vp->v_iflag & VI_DOINGINACT) && 2198 vp->v_usecount == 1)) { 2199 if (func == VPUTX_VPUT) 2200 VOP_UNLOCK(vp, 0); 2201 v_decr_usecount(vp); 2202 return; 2203 } 2204 2205 if (vp->v_usecount != 1) { 2206 #ifdef DIAGNOSTIC 2207 vprint("vputx: negative ref count", vp); 2208 #endif 2209 panic("vputx: negative ref cnt"); 2210 } 2211 CTR2(KTR_VFS, "%s: return vnode %p to the freelist", __func__, vp); 2212 /* 2213 * We want to hold the vnode until the inactive finishes to 2214 * prevent vgone() races. We drop the use count here and the 2215 * hold count below when we're done. 2216 */ 2217 v_decr_useonly(vp); 2218 /* 2219 * We must call VOP_INACTIVE with the node locked. Mark 2220 * as VI_DOINGINACT to avoid recursion. 2221 */ 2222 vp->v_iflag |= VI_OWEINACT; 2223 if (func == VPUTX_VRELE) { 2224 error = vn_lock(vp, LK_EXCLUSIVE | LK_INTERLOCK); 2225 VI_LOCK(vp); 2226 } else if (func == VPUTX_VPUT && VOP_ISLOCKED(vp) != LK_EXCLUSIVE) { 2227 error = VOP_LOCK(vp, LK_UPGRADE | LK_INTERLOCK | LK_NOWAIT); 2228 VI_LOCK(vp); 2229 } 2230 if (vp->v_usecount > 0) 2231 vp->v_iflag &= ~VI_OWEINACT; 2232 if (error == 0) { 2233 if (vp->v_iflag & VI_OWEINACT) 2234 vinactive(vp, curthread); 2235 if (func != VPUTX_VUNREF) 2236 VOP_UNLOCK(vp, 0); 2237 } 2238 vdropl(vp); 2239 } 2240 2241 /* 2242 * Vnode put/release. 2243 * If count drops to zero, call inactive routine and return to freelist. 2244 */ 2245 void 2246 vrele(struct vnode *vp) 2247 { 2248 2249 vputx(vp, VPUTX_VRELE); 2250 } 2251 2252 /* 2253 * Release an already locked vnode. This give the same effects as 2254 * unlock+vrele(), but takes less time and avoids releasing and 2255 * re-aquiring the lock (as vrele() acquires the lock internally.) 2256 */ 2257 void 2258 vput(struct vnode *vp) 2259 { 2260 2261 vputx(vp, VPUTX_VPUT); 2262 } 2263 2264 /* 2265 * Release an exclusively locked vnode. Do not unlock the vnode lock. 2266 */ 2267 void 2268 vunref(struct vnode *vp) 2269 { 2270 2271 vputx(vp, VPUTX_VUNREF); 2272 } 2273 2274 /* 2275 * Somebody doesn't want the vnode recycled. 2276 */ 2277 void 2278 vhold(struct vnode *vp) 2279 { 2280 2281 VI_LOCK(vp); 2282 vholdl(vp); 2283 VI_UNLOCK(vp); 2284 } 2285 2286 void 2287 vholdl(struct vnode *vp) 2288 { 2289 2290 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2291 vp->v_holdcnt++; 2292 if (VSHOULDBUSY(vp)) 2293 vbusy(vp); 2294 } 2295 2296 /* 2297 * Note that there is one less who cares about this vnode. vdrop() is the 2298 * opposite of vhold(). 2299 */ 2300 void 2301 vdrop(struct vnode *vp) 2302 { 2303 2304 VI_LOCK(vp); 2305 vdropl(vp); 2306 } 2307 2308 /* 2309 * Drop the hold count of the vnode. If this is the last reference to 2310 * the vnode we will free it if it has been vgone'd otherwise it is 2311 * placed on the free list. 2312 */ 2313 void 2314 vdropl(struct vnode *vp) 2315 { 2316 2317 ASSERT_VI_LOCKED(vp, "vdropl"); 2318 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2319 if (vp->v_holdcnt <= 0) 2320 panic("vdrop: holdcnt %d", vp->v_holdcnt); 2321 vp->v_holdcnt--; 2322 if (vp->v_holdcnt == 0) { 2323 if (vp->v_iflag & VI_DOOMED) { 2324 CTR2(KTR_VFS, "%s: destroying the vnode %p", __func__, 2325 vp); 2326 vdestroy(vp); 2327 return; 2328 } else 2329 vfree(vp); 2330 } 2331 VI_UNLOCK(vp); 2332 } 2333 2334 /* 2335 * Call VOP_INACTIVE on the vnode and manage the DOINGINACT and OWEINACT 2336 * flags. DOINGINACT prevents us from recursing in calls to vinactive. 2337 * OWEINACT tracks whether a vnode missed a call to inactive due to a 2338 * failed lock upgrade. 2339 */ 2340 static void 2341 vinactive(struct vnode *vp, struct thread *td) 2342 { 2343 2344 ASSERT_VOP_ELOCKED(vp, "vinactive"); 2345 ASSERT_VI_LOCKED(vp, "vinactive"); 2346 VNASSERT((vp->v_iflag & VI_DOINGINACT) == 0, vp, 2347 ("vinactive: recursed on VI_DOINGINACT")); 2348 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2349 vp->v_iflag |= VI_DOINGINACT; 2350 vp->v_iflag &= ~VI_OWEINACT; 2351 VI_UNLOCK(vp); 2352 VOP_INACTIVE(vp, td); 2353 VI_LOCK(vp); 2354 VNASSERT(vp->v_iflag & VI_DOINGINACT, vp, 2355 ("vinactive: lost VI_DOINGINACT")); 2356 vp->v_iflag &= ~VI_DOINGINACT; 2357 } 2358 2359 /* 2360 * Remove any vnodes in the vnode table belonging to mount point mp. 2361 * 2362 * If FORCECLOSE is not specified, there should not be any active ones, 2363 * return error if any are found (nb: this is a user error, not a 2364 * system error). If FORCECLOSE is specified, detach any active vnodes 2365 * that are found. 2366 * 2367 * If WRITECLOSE is set, only flush out regular file vnodes open for 2368 * writing. 2369 * 2370 * SKIPSYSTEM causes any vnodes marked VV_SYSTEM to be skipped. 2371 * 2372 * `rootrefs' specifies the base reference count for the root vnode 2373 * of this filesystem. The root vnode is considered busy if its 2374 * v_usecount exceeds this value. On a successful return, vflush(, td) 2375 * will call vrele() on the root vnode exactly rootrefs times. 2376 * If the SKIPSYSTEM or WRITECLOSE flags are specified, rootrefs must 2377 * be zero. 2378 */ 2379 #ifdef DIAGNOSTIC 2380 static int busyprt = 0; /* print out busy vnodes */ 2381 SYSCTL_INT(_debug, OID_AUTO, busyprt, CTLFLAG_RW, &busyprt, 0, ""); 2382 #endif 2383 2384 int 2385 vflush(struct mount *mp, int rootrefs, int flags, struct thread *td) 2386 { 2387 struct vnode *vp, *mvp, *rootvp = NULL; 2388 struct vattr vattr; 2389 int busy = 0, error; 2390 2391 CTR4(KTR_VFS, "%s: mp %p with rootrefs %d and flags %d", __func__, mp, 2392 rootrefs, flags); 2393 if (rootrefs > 0) { 2394 KASSERT((flags & (SKIPSYSTEM | WRITECLOSE)) == 0, 2395 ("vflush: bad args")); 2396 /* 2397 * Get the filesystem root vnode. We can vput() it 2398 * immediately, since with rootrefs > 0, it won't go away. 2399 */ 2400 if ((error = VFS_ROOT(mp, LK_EXCLUSIVE, &rootvp)) != 0) { 2401 CTR2(KTR_VFS, "%s: vfs_root lookup failed with %d", 2402 __func__, error); 2403 return (error); 2404 } 2405 vput(rootvp); 2406 } 2407 MNT_ILOCK(mp); 2408 loop: 2409 MNT_VNODE_FOREACH(vp, mp, mvp) { 2410 VI_LOCK(vp); 2411 vholdl(vp); 2412 MNT_IUNLOCK(mp); 2413 error = vn_lock(vp, LK_INTERLOCK | LK_EXCLUSIVE); 2414 if (error) { 2415 vdrop(vp); 2416 MNT_ILOCK(mp); 2417 MNT_VNODE_FOREACH_ABORT_ILOCKED(mp, mvp); 2418 goto loop; 2419 } 2420 /* 2421 * Skip over a vnodes marked VV_SYSTEM. 2422 */ 2423 if ((flags & SKIPSYSTEM) && (vp->v_vflag & VV_SYSTEM)) { 2424 VOP_UNLOCK(vp, 0); 2425 vdrop(vp); 2426 MNT_ILOCK(mp); 2427 continue; 2428 } 2429 /* 2430 * If WRITECLOSE is set, flush out unlinked but still open 2431 * files (even if open only for reading) and regular file 2432 * vnodes open for writing. 2433 */ 2434 if (flags & WRITECLOSE) { 2435 error = VOP_GETATTR(vp, &vattr, td->td_ucred); 2436 VI_LOCK(vp); 2437 2438 if ((vp->v_type == VNON || 2439 (error == 0 && vattr.va_nlink > 0)) && 2440 (vp->v_writecount == 0 || vp->v_type != VREG)) { 2441 VOP_UNLOCK(vp, 0); 2442 vdropl(vp); 2443 MNT_ILOCK(mp); 2444 continue; 2445 } 2446 } else 2447 VI_LOCK(vp); 2448 /* 2449 * With v_usecount == 0, all we need to do is clear out the 2450 * vnode data structures and we are done. 2451 * 2452 * If FORCECLOSE is set, forcibly close the vnode. 2453 */ 2454 if (vp->v_usecount == 0 || (flags & FORCECLOSE)) { 2455 VNASSERT(vp->v_usecount == 0 || 2456 (vp->v_type != VCHR && vp->v_type != VBLK), vp, 2457 ("device VNODE %p is FORCECLOSED", vp)); 2458 vgonel(vp); 2459 } else { 2460 busy++; 2461 #ifdef DIAGNOSTIC 2462 if (busyprt) 2463 vprint("vflush: busy vnode", vp); 2464 #endif 2465 } 2466 VOP_UNLOCK(vp, 0); 2467 vdropl(vp); 2468 MNT_ILOCK(mp); 2469 } 2470 MNT_IUNLOCK(mp); 2471 if (rootrefs > 0 && (flags & FORCECLOSE) == 0) { 2472 /* 2473 * If just the root vnode is busy, and if its refcount 2474 * is equal to `rootrefs', then go ahead and kill it. 2475 */ 2476 VI_LOCK(rootvp); 2477 KASSERT(busy > 0, ("vflush: not busy")); 2478 VNASSERT(rootvp->v_usecount >= rootrefs, rootvp, 2479 ("vflush: usecount %d < rootrefs %d", 2480 rootvp->v_usecount, rootrefs)); 2481 if (busy == 1 && rootvp->v_usecount == rootrefs) { 2482 VOP_LOCK(rootvp, LK_EXCLUSIVE|LK_INTERLOCK); 2483 vgone(rootvp); 2484 VOP_UNLOCK(rootvp, 0); 2485 busy = 0; 2486 } else 2487 VI_UNLOCK(rootvp); 2488 } 2489 if (busy) { 2490 CTR2(KTR_VFS, "%s: failing as %d vnodes are busy", __func__, 2491 busy); 2492 return (EBUSY); 2493 } 2494 for (; rootrefs > 0; rootrefs--) 2495 vrele(rootvp); 2496 return (0); 2497 } 2498 2499 /* 2500 * Recycle an unused vnode to the front of the free list. 2501 */ 2502 int 2503 vrecycle(struct vnode *vp, struct thread *td) 2504 { 2505 int recycled; 2506 2507 ASSERT_VOP_ELOCKED(vp, "vrecycle"); 2508 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2509 recycled = 0; 2510 VI_LOCK(vp); 2511 if (vp->v_usecount == 0) { 2512 recycled = 1; 2513 vgonel(vp); 2514 } 2515 VI_UNLOCK(vp); 2516 return (recycled); 2517 } 2518 2519 /* 2520 * Eliminate all activity associated with a vnode 2521 * in preparation for reuse. 2522 */ 2523 void 2524 vgone(struct vnode *vp) 2525 { 2526 VI_LOCK(vp); 2527 vgonel(vp); 2528 VI_UNLOCK(vp); 2529 } 2530 2531 /* 2532 * vgone, with the vp interlock held. 2533 */ 2534 void 2535 vgonel(struct vnode *vp) 2536 { 2537 struct thread *td; 2538 int oweinact; 2539 int active; 2540 struct mount *mp; 2541 2542 ASSERT_VOP_ELOCKED(vp, "vgonel"); 2543 ASSERT_VI_LOCKED(vp, "vgonel"); 2544 VNASSERT(vp->v_holdcnt, vp, 2545 ("vgonel: vp %p has no reference.", vp)); 2546 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2547 td = curthread; 2548 2549 /* 2550 * Don't vgonel if we're already doomed. 2551 */ 2552 if (vp->v_iflag & VI_DOOMED) 2553 return; 2554 vp->v_iflag |= VI_DOOMED; 2555 /* 2556 * Check to see if the vnode is in use. If so, we have to call 2557 * VOP_CLOSE() and VOP_INACTIVE(). 2558 */ 2559 active = vp->v_usecount; 2560 oweinact = (vp->v_iflag & VI_OWEINACT); 2561 VI_UNLOCK(vp); 2562 /* 2563 * Clean out any buffers associated with the vnode. 2564 * If the flush fails, just toss the buffers. 2565 */ 2566 mp = NULL; 2567 if (!TAILQ_EMPTY(&vp->v_bufobj.bo_dirty.bv_hd)) 2568 (void) vn_start_secondary_write(vp, &mp, V_WAIT); 2569 if (vinvalbuf(vp, V_SAVE, 0, 0) != 0) 2570 vinvalbuf(vp, 0, 0, 0); 2571 2572 /* 2573 * If purging an active vnode, it must be closed and 2574 * deactivated before being reclaimed. 2575 */ 2576 if (active) 2577 VOP_CLOSE(vp, FNONBLOCK, NOCRED, td); 2578 if (oweinact || active) { 2579 VI_LOCK(vp); 2580 if ((vp->v_iflag & VI_DOINGINACT) == 0) 2581 vinactive(vp, td); 2582 VI_UNLOCK(vp); 2583 } 2584 /* 2585 * Reclaim the vnode. 2586 */ 2587 if (VOP_RECLAIM(vp, td)) 2588 panic("vgone: cannot reclaim"); 2589 if (mp != NULL) 2590 vn_finished_secondary_write(mp); 2591 VNASSERT(vp->v_object == NULL, vp, 2592 ("vop_reclaim left v_object vp=%p, tag=%s", vp, vp->v_tag)); 2593 /* 2594 * Clear the advisory locks and wake up waiting threads. 2595 */ 2596 (void)VOP_ADVLOCKPURGE(vp); 2597 /* 2598 * Delete from old mount point vnode list. 2599 */ 2600 delmntque(vp); 2601 cache_purge(vp); 2602 /* 2603 * Done with purge, reset to the standard lock and invalidate 2604 * the vnode. 2605 */ 2606 VI_LOCK(vp); 2607 vp->v_vnlock = &vp->v_lock; 2608 vp->v_op = &dead_vnodeops; 2609 vp->v_tag = "none"; 2610 vp->v_type = VBAD; 2611 } 2612 2613 /* 2614 * Calculate the total number of references to a special device. 2615 */ 2616 int 2617 vcount(struct vnode *vp) 2618 { 2619 int count; 2620 2621 dev_lock(); 2622 count = vp->v_rdev->si_usecount; 2623 dev_unlock(); 2624 return (count); 2625 } 2626 2627 /* 2628 * Same as above, but using the struct cdev *as argument 2629 */ 2630 int 2631 count_dev(struct cdev *dev) 2632 { 2633 int count; 2634 2635 dev_lock(); 2636 count = dev->si_usecount; 2637 dev_unlock(); 2638 return(count); 2639 } 2640 2641 /* 2642 * Print out a description of a vnode. 2643 */ 2644 static char *typename[] = 2645 {"VNON", "VREG", "VDIR", "VBLK", "VCHR", "VLNK", "VSOCK", "VFIFO", "VBAD", 2646 "VMARKER"}; 2647 2648 void 2649 vn_printf(struct vnode *vp, const char *fmt, ...) 2650 { 2651 va_list ap; 2652 char buf[256], buf2[16]; 2653 u_long flags; 2654 2655 va_start(ap, fmt); 2656 vprintf(fmt, ap); 2657 va_end(ap); 2658 printf("%p: ", (void *)vp); 2659 printf("tag %s, type %s\n", vp->v_tag, typename[vp->v_type]); 2660 printf(" usecount %d, writecount %d, refcount %d mountedhere %p\n", 2661 vp->v_usecount, vp->v_writecount, vp->v_holdcnt, vp->v_mountedhere); 2662 buf[0] = '\0'; 2663 buf[1] = '\0'; 2664 if (vp->v_vflag & VV_ROOT) 2665 strlcat(buf, "|VV_ROOT", sizeof(buf)); 2666 if (vp->v_vflag & VV_ISTTY) 2667 strlcat(buf, "|VV_ISTTY", sizeof(buf)); 2668 if (vp->v_vflag & VV_NOSYNC) 2669 strlcat(buf, "|VV_NOSYNC", sizeof(buf)); 2670 if (vp->v_vflag & VV_CACHEDLABEL) 2671 strlcat(buf, "|VV_CACHEDLABEL", sizeof(buf)); 2672 if (vp->v_vflag & VV_TEXT) 2673 strlcat(buf, "|VV_TEXT", sizeof(buf)); 2674 if (vp->v_vflag & VV_COPYONWRITE) 2675 strlcat(buf, "|VV_COPYONWRITE", sizeof(buf)); 2676 if (vp->v_vflag & VV_SYSTEM) 2677 strlcat(buf, "|VV_SYSTEM", sizeof(buf)); 2678 if (vp->v_vflag & VV_PROCDEP) 2679 strlcat(buf, "|VV_PROCDEP", sizeof(buf)); 2680 if (vp->v_vflag & VV_NOKNOTE) 2681 strlcat(buf, "|VV_NOKNOTE", sizeof(buf)); 2682 if (vp->v_vflag & VV_DELETED) 2683 strlcat(buf, "|VV_DELETED", sizeof(buf)); 2684 if (vp->v_vflag & VV_MD) 2685 strlcat(buf, "|VV_MD", sizeof(buf)); 2686 flags = vp->v_vflag & ~(VV_ROOT | VV_ISTTY | VV_NOSYNC | 2687 VV_CACHEDLABEL | VV_TEXT | VV_COPYONWRITE | VV_SYSTEM | VV_PROCDEP | 2688 VV_NOKNOTE | VV_DELETED | VV_MD); 2689 if (flags != 0) { 2690 snprintf(buf2, sizeof(buf2), "|VV(0x%lx)", flags); 2691 strlcat(buf, buf2, sizeof(buf)); 2692 } 2693 if (vp->v_iflag & VI_MOUNT) 2694 strlcat(buf, "|VI_MOUNT", sizeof(buf)); 2695 if (vp->v_iflag & VI_AGE) 2696 strlcat(buf, "|VI_AGE", sizeof(buf)); 2697 if (vp->v_iflag & VI_DOOMED) 2698 strlcat(buf, "|VI_DOOMED", sizeof(buf)); 2699 if (vp->v_iflag & VI_FREE) 2700 strlcat(buf, "|VI_FREE", sizeof(buf)); 2701 if (vp->v_iflag & VI_DOINGINACT) 2702 strlcat(buf, "|VI_DOINGINACT", sizeof(buf)); 2703 if (vp->v_iflag & VI_OWEINACT) 2704 strlcat(buf, "|VI_OWEINACT", sizeof(buf)); 2705 flags = vp->v_iflag & ~(VI_MOUNT | VI_AGE | VI_DOOMED | VI_FREE | 2706 VI_DOINGINACT | VI_OWEINACT); 2707 if (flags != 0) { 2708 snprintf(buf2, sizeof(buf2), "|VI(0x%lx)", flags); 2709 strlcat(buf, buf2, sizeof(buf)); 2710 } 2711 printf(" flags (%s)\n", buf + 1); 2712 if (mtx_owned(VI_MTX(vp))) 2713 printf(" VI_LOCKed"); 2714 if (vp->v_object != NULL) 2715 printf(" v_object %p ref %d pages %d\n", 2716 vp->v_object, vp->v_object->ref_count, 2717 vp->v_object->resident_page_count); 2718 printf(" "); 2719 lockmgr_printinfo(vp->v_vnlock); 2720 if (vp->v_data != NULL) 2721 VOP_PRINT(vp); 2722 } 2723 2724 #ifdef DDB 2725 /* 2726 * List all of the locked vnodes in the system. 2727 * Called when debugging the kernel. 2728 */ 2729 DB_SHOW_COMMAND(lockedvnods, lockedvnodes) 2730 { 2731 struct mount *mp, *nmp; 2732 struct vnode *vp; 2733 2734 /* 2735 * Note: because this is DDB, we can't obey the locking semantics 2736 * for these structures, which means we could catch an inconsistent 2737 * state and dereference a nasty pointer. Not much to be done 2738 * about that. 2739 */ 2740 db_printf("Locked vnodes\n"); 2741 for (mp = TAILQ_FIRST(&mountlist); mp != NULL; mp = nmp) { 2742 nmp = TAILQ_NEXT(mp, mnt_list); 2743 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) { 2744 if (vp->v_type != VMARKER && 2745 VOP_ISLOCKED(vp)) 2746 vprint("", vp); 2747 } 2748 nmp = TAILQ_NEXT(mp, mnt_list); 2749 } 2750 } 2751 2752 /* 2753 * Show details about the given vnode. 2754 */ 2755 DB_SHOW_COMMAND(vnode, db_show_vnode) 2756 { 2757 struct vnode *vp; 2758 2759 if (!have_addr) 2760 return; 2761 vp = (struct vnode *)addr; 2762 vn_printf(vp, "vnode "); 2763 } 2764 2765 /* 2766 * Show details about the given mount point. 2767 */ 2768 DB_SHOW_COMMAND(mount, db_show_mount) 2769 { 2770 struct mount *mp; 2771 struct vfsopt *opt; 2772 struct statfs *sp; 2773 struct vnode *vp; 2774 char buf[512]; 2775 u_int flags; 2776 2777 if (!have_addr) { 2778 /* No address given, print short info about all mount points. */ 2779 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 2780 db_printf("%p %s on %s (%s)\n", mp, 2781 mp->mnt_stat.f_mntfromname, 2782 mp->mnt_stat.f_mntonname, 2783 mp->mnt_stat.f_fstypename); 2784 if (db_pager_quit) 2785 break; 2786 } 2787 db_printf("\nMore info: show mount <addr>\n"); 2788 return; 2789 } 2790 2791 mp = (struct mount *)addr; 2792 db_printf("%p %s on %s (%s)\n", mp, mp->mnt_stat.f_mntfromname, 2793 mp->mnt_stat.f_mntonname, mp->mnt_stat.f_fstypename); 2794 2795 buf[0] = '\0'; 2796 flags = mp->mnt_flag; 2797 #define MNT_FLAG(flag) do { \ 2798 if (flags & (flag)) { \ 2799 if (buf[0] != '\0') \ 2800 strlcat(buf, ", ", sizeof(buf)); \ 2801 strlcat(buf, (#flag) + 4, sizeof(buf)); \ 2802 flags &= ~(flag); \ 2803 } \ 2804 } while (0) 2805 MNT_FLAG(MNT_RDONLY); 2806 MNT_FLAG(MNT_SYNCHRONOUS); 2807 MNT_FLAG(MNT_NOEXEC); 2808 MNT_FLAG(MNT_NOSUID); 2809 MNT_FLAG(MNT_UNION); 2810 MNT_FLAG(MNT_ASYNC); 2811 MNT_FLAG(MNT_SUIDDIR); 2812 MNT_FLAG(MNT_SOFTDEP); 2813 MNT_FLAG(MNT_NOSYMFOLLOW); 2814 MNT_FLAG(MNT_GJOURNAL); 2815 MNT_FLAG(MNT_MULTILABEL); 2816 MNT_FLAG(MNT_ACLS); 2817 MNT_FLAG(MNT_NOATIME); 2818 MNT_FLAG(MNT_NOCLUSTERR); 2819 MNT_FLAG(MNT_NOCLUSTERW); 2820 MNT_FLAG(MNT_NFS4ACLS); 2821 MNT_FLAG(MNT_EXRDONLY); 2822 MNT_FLAG(MNT_EXPORTED); 2823 MNT_FLAG(MNT_DEFEXPORTED); 2824 MNT_FLAG(MNT_EXPORTANON); 2825 MNT_FLAG(MNT_EXKERB); 2826 MNT_FLAG(MNT_EXPUBLIC); 2827 MNT_FLAG(MNT_LOCAL); 2828 MNT_FLAG(MNT_QUOTA); 2829 MNT_FLAG(MNT_ROOTFS); 2830 MNT_FLAG(MNT_USER); 2831 MNT_FLAG(MNT_IGNORE); 2832 MNT_FLAG(MNT_UPDATE); 2833 MNT_FLAG(MNT_DELEXPORT); 2834 MNT_FLAG(MNT_RELOAD); 2835 MNT_FLAG(MNT_FORCE); 2836 MNT_FLAG(MNT_SNAPSHOT); 2837 MNT_FLAG(MNT_BYFSID); 2838 MNT_FLAG(MNT_SOFTDEP); 2839 #undef MNT_FLAG 2840 if (flags != 0) { 2841 if (buf[0] != '\0') 2842 strlcat(buf, ", ", sizeof(buf)); 2843 snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf), 2844 "0x%08x", flags); 2845 } 2846 db_printf(" mnt_flag = %s\n", buf); 2847 2848 buf[0] = '\0'; 2849 flags = mp->mnt_kern_flag; 2850 #define MNT_KERN_FLAG(flag) do { \ 2851 if (flags & (flag)) { \ 2852 if (buf[0] != '\0') \ 2853 strlcat(buf, ", ", sizeof(buf)); \ 2854 strlcat(buf, (#flag) + 5, sizeof(buf)); \ 2855 flags &= ~(flag); \ 2856 } \ 2857 } while (0) 2858 MNT_KERN_FLAG(MNTK_UNMOUNTF); 2859 MNT_KERN_FLAG(MNTK_ASYNC); 2860 MNT_KERN_FLAG(MNTK_SOFTDEP); 2861 MNT_KERN_FLAG(MNTK_NOINSMNTQ); 2862 MNT_KERN_FLAG(MNTK_DRAINING); 2863 MNT_KERN_FLAG(MNTK_REFEXPIRE); 2864 MNT_KERN_FLAG(MNTK_EXTENDED_SHARED); 2865 MNT_KERN_FLAG(MNTK_SHARED_WRITES); 2866 MNT_KERN_FLAG(MNTK_UNMOUNT); 2867 MNT_KERN_FLAG(MNTK_MWAIT); 2868 MNT_KERN_FLAG(MNTK_SUSPEND); 2869 MNT_KERN_FLAG(MNTK_SUSPEND2); 2870 MNT_KERN_FLAG(MNTK_SUSPENDED); 2871 MNT_KERN_FLAG(MNTK_MPSAFE); 2872 MNT_KERN_FLAG(MNTK_LOOKUP_SHARED); 2873 MNT_KERN_FLAG(MNTK_NOKNOTE); 2874 #undef MNT_KERN_FLAG 2875 if (flags != 0) { 2876 if (buf[0] != '\0') 2877 strlcat(buf, ", ", sizeof(buf)); 2878 snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf), 2879 "0x%08x", flags); 2880 } 2881 db_printf(" mnt_kern_flag = %s\n", buf); 2882 2883 db_printf(" mnt_opt = "); 2884 opt = TAILQ_FIRST(mp->mnt_opt); 2885 if (opt != NULL) { 2886 db_printf("%s", opt->name); 2887 opt = TAILQ_NEXT(opt, link); 2888 while (opt != NULL) { 2889 db_printf(", %s", opt->name); 2890 opt = TAILQ_NEXT(opt, link); 2891 } 2892 } 2893 db_printf("\n"); 2894 2895 sp = &mp->mnt_stat; 2896 db_printf(" mnt_stat = { version=%u type=%u flags=0x%016jx " 2897 "bsize=%ju iosize=%ju blocks=%ju bfree=%ju bavail=%jd files=%ju " 2898 "ffree=%jd syncwrites=%ju asyncwrites=%ju syncreads=%ju " 2899 "asyncreads=%ju namemax=%u owner=%u fsid=[%d, %d] }\n", 2900 (u_int)sp->f_version, (u_int)sp->f_type, (uintmax_t)sp->f_flags, 2901 (uintmax_t)sp->f_bsize, (uintmax_t)sp->f_iosize, 2902 (uintmax_t)sp->f_blocks, (uintmax_t)sp->f_bfree, 2903 (intmax_t)sp->f_bavail, (uintmax_t)sp->f_files, 2904 (intmax_t)sp->f_ffree, (uintmax_t)sp->f_syncwrites, 2905 (uintmax_t)sp->f_asyncwrites, (uintmax_t)sp->f_syncreads, 2906 (uintmax_t)sp->f_asyncreads, (u_int)sp->f_namemax, 2907 (u_int)sp->f_owner, (int)sp->f_fsid.val[0], (int)sp->f_fsid.val[1]); 2908 2909 db_printf(" mnt_cred = { uid=%u ruid=%u", 2910 (u_int)mp->mnt_cred->cr_uid, (u_int)mp->mnt_cred->cr_ruid); 2911 if (jailed(mp->mnt_cred)) 2912 db_printf(", jail=%d", mp->mnt_cred->cr_prison->pr_id); 2913 db_printf(" }\n"); 2914 db_printf(" mnt_ref = %d\n", mp->mnt_ref); 2915 db_printf(" mnt_gen = %d\n", mp->mnt_gen); 2916 db_printf(" mnt_nvnodelistsize = %d\n", mp->mnt_nvnodelistsize); 2917 db_printf(" mnt_writeopcount = %d\n", mp->mnt_writeopcount); 2918 db_printf(" mnt_noasync = %u\n", mp->mnt_noasync); 2919 db_printf(" mnt_maxsymlinklen = %d\n", mp->mnt_maxsymlinklen); 2920 db_printf(" mnt_iosize_max = %d\n", mp->mnt_iosize_max); 2921 db_printf(" mnt_hashseed = %u\n", mp->mnt_hashseed); 2922 db_printf(" mnt_secondary_writes = %d\n", mp->mnt_secondary_writes); 2923 db_printf(" mnt_secondary_accwrites = %d\n", 2924 mp->mnt_secondary_accwrites); 2925 db_printf(" mnt_gjprovider = %s\n", 2926 mp->mnt_gjprovider != NULL ? mp->mnt_gjprovider : "NULL"); 2927 db_printf("\n"); 2928 2929 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) { 2930 if (vp->v_type != VMARKER) { 2931 vn_printf(vp, "vnode "); 2932 if (db_pager_quit) 2933 break; 2934 } 2935 } 2936 } 2937 #endif /* DDB */ 2938 2939 /* 2940 * Fill in a struct xvfsconf based on a struct vfsconf. 2941 */ 2942 static void 2943 vfsconf2x(struct vfsconf *vfsp, struct xvfsconf *xvfsp) 2944 { 2945 2946 strcpy(xvfsp->vfc_name, vfsp->vfc_name); 2947 xvfsp->vfc_typenum = vfsp->vfc_typenum; 2948 xvfsp->vfc_refcount = vfsp->vfc_refcount; 2949 xvfsp->vfc_flags = vfsp->vfc_flags; 2950 /* 2951 * These are unused in userland, we keep them 2952 * to not break binary compatibility. 2953 */ 2954 xvfsp->vfc_vfsops = NULL; 2955 xvfsp->vfc_next = NULL; 2956 } 2957 2958 /* 2959 * Top level filesystem related information gathering. 2960 */ 2961 static int 2962 sysctl_vfs_conflist(SYSCTL_HANDLER_ARGS) 2963 { 2964 struct vfsconf *vfsp; 2965 struct xvfsconf xvfsp; 2966 int error; 2967 2968 error = 0; 2969 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) { 2970 bzero(&xvfsp, sizeof(xvfsp)); 2971 vfsconf2x(vfsp, &xvfsp); 2972 error = SYSCTL_OUT(req, &xvfsp, sizeof xvfsp); 2973 if (error) 2974 break; 2975 } 2976 return (error); 2977 } 2978 2979 SYSCTL_PROC(_vfs, OID_AUTO, conflist, CTLFLAG_RD, NULL, 0, sysctl_vfs_conflist, 2980 "S,xvfsconf", "List of all configured filesystems"); 2981 2982 #ifndef BURN_BRIDGES 2983 static int sysctl_ovfs_conf(SYSCTL_HANDLER_ARGS); 2984 2985 static int 2986 vfs_sysctl(SYSCTL_HANDLER_ARGS) 2987 { 2988 int *name = (int *)arg1 - 1; /* XXX */ 2989 u_int namelen = arg2 + 1; /* XXX */ 2990 struct vfsconf *vfsp; 2991 struct xvfsconf xvfsp; 2992 2993 printf("WARNING: userland calling deprecated sysctl, " 2994 "please rebuild world\n"); 2995 2996 #if 1 || defined(COMPAT_PRELITE2) 2997 /* Resolve ambiguity between VFS_VFSCONF and VFS_GENERIC. */ 2998 if (namelen == 1) 2999 return (sysctl_ovfs_conf(oidp, arg1, arg2, req)); 3000 #endif 3001 3002 switch (name[1]) { 3003 case VFS_MAXTYPENUM: 3004 if (namelen != 2) 3005 return (ENOTDIR); 3006 return (SYSCTL_OUT(req, &maxvfsconf, sizeof(int))); 3007 case VFS_CONF: 3008 if (namelen != 3) 3009 return (ENOTDIR); /* overloaded */ 3010 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) 3011 if (vfsp->vfc_typenum == name[2]) 3012 break; 3013 if (vfsp == NULL) 3014 return (EOPNOTSUPP); 3015 bzero(&xvfsp, sizeof(xvfsp)); 3016 vfsconf2x(vfsp, &xvfsp); 3017 return (SYSCTL_OUT(req, &xvfsp, sizeof(xvfsp))); 3018 } 3019 return (EOPNOTSUPP); 3020 } 3021 3022 static SYSCTL_NODE(_vfs, VFS_GENERIC, generic, CTLFLAG_RD | CTLFLAG_SKIP, 3023 vfs_sysctl, "Generic filesystem"); 3024 3025 #if 1 || defined(COMPAT_PRELITE2) 3026 3027 static int 3028 sysctl_ovfs_conf(SYSCTL_HANDLER_ARGS) 3029 { 3030 int error; 3031 struct vfsconf *vfsp; 3032 struct ovfsconf ovfs; 3033 3034 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) { 3035 bzero(&ovfs, sizeof(ovfs)); 3036 ovfs.vfc_vfsops = vfsp->vfc_vfsops; /* XXX used as flag */ 3037 strcpy(ovfs.vfc_name, vfsp->vfc_name); 3038 ovfs.vfc_index = vfsp->vfc_typenum; 3039 ovfs.vfc_refcount = vfsp->vfc_refcount; 3040 ovfs.vfc_flags = vfsp->vfc_flags; 3041 error = SYSCTL_OUT(req, &ovfs, sizeof ovfs); 3042 if (error) 3043 return error; 3044 } 3045 return 0; 3046 } 3047 3048 #endif /* 1 || COMPAT_PRELITE2 */ 3049 #endif /* !BURN_BRIDGES */ 3050 3051 #define KINFO_VNODESLOP 10 3052 #ifdef notyet 3053 /* 3054 * Dump vnode list (via sysctl). 3055 */ 3056 /* ARGSUSED */ 3057 static int 3058 sysctl_vnode(SYSCTL_HANDLER_ARGS) 3059 { 3060 struct xvnode *xvn; 3061 struct mount *mp; 3062 struct vnode *vp; 3063 int error, len, n; 3064 3065 /* 3066 * Stale numvnodes access is not fatal here. 3067 */ 3068 req->lock = 0; 3069 len = (numvnodes + KINFO_VNODESLOP) * sizeof *xvn; 3070 if (!req->oldptr) 3071 /* Make an estimate */ 3072 return (SYSCTL_OUT(req, 0, len)); 3073 3074 error = sysctl_wire_old_buffer(req, 0); 3075 if (error != 0) 3076 return (error); 3077 xvn = malloc(len, M_TEMP, M_ZERO | M_WAITOK); 3078 n = 0; 3079 mtx_lock(&mountlist_mtx); 3080 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 3081 if (vfs_busy(mp, MBF_NOWAIT | MBF_MNTLSTLOCK)) 3082 continue; 3083 MNT_ILOCK(mp); 3084 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) { 3085 if (n == len) 3086 break; 3087 vref(vp); 3088 xvn[n].xv_size = sizeof *xvn; 3089 xvn[n].xv_vnode = vp; 3090 xvn[n].xv_id = 0; /* XXX compat */ 3091 #define XV_COPY(field) xvn[n].xv_##field = vp->v_##field 3092 XV_COPY(usecount); 3093 XV_COPY(writecount); 3094 XV_COPY(holdcnt); 3095 XV_COPY(mount); 3096 XV_COPY(numoutput); 3097 XV_COPY(type); 3098 #undef XV_COPY 3099 xvn[n].xv_flag = vp->v_vflag; 3100 3101 switch (vp->v_type) { 3102 case VREG: 3103 case VDIR: 3104 case VLNK: 3105 break; 3106 case VBLK: 3107 case VCHR: 3108 if (vp->v_rdev == NULL) { 3109 vrele(vp); 3110 continue; 3111 } 3112 xvn[n].xv_dev = dev2udev(vp->v_rdev); 3113 break; 3114 case VSOCK: 3115 xvn[n].xv_socket = vp->v_socket; 3116 break; 3117 case VFIFO: 3118 xvn[n].xv_fifo = vp->v_fifoinfo; 3119 break; 3120 case VNON: 3121 case VBAD: 3122 default: 3123 /* shouldn't happen? */ 3124 vrele(vp); 3125 continue; 3126 } 3127 vrele(vp); 3128 ++n; 3129 } 3130 MNT_IUNLOCK(mp); 3131 mtx_lock(&mountlist_mtx); 3132 vfs_unbusy(mp); 3133 if (n == len) 3134 break; 3135 } 3136 mtx_unlock(&mountlist_mtx); 3137 3138 error = SYSCTL_OUT(req, xvn, n * sizeof *xvn); 3139 free(xvn, M_TEMP); 3140 return (error); 3141 } 3142 3143 SYSCTL_PROC(_kern, KERN_VNODE, vnode, CTLTYPE_OPAQUE|CTLFLAG_RD, 3144 0, 0, sysctl_vnode, "S,xvnode", ""); 3145 #endif 3146 3147 /* 3148 * Unmount all filesystems. The list is traversed in reverse order 3149 * of mounting to avoid dependencies. 3150 */ 3151 void 3152 vfs_unmountall(void) 3153 { 3154 struct mount *mp; 3155 struct thread *td; 3156 int error; 3157 3158 KASSERT(curthread != NULL, ("vfs_unmountall: NULL curthread")); 3159 CTR1(KTR_VFS, "%s: unmounting all filesystems", __func__); 3160 td = curthread; 3161 3162 /* 3163 * Since this only runs when rebooting, it is not interlocked. 3164 */ 3165 while(!TAILQ_EMPTY(&mountlist)) { 3166 mp = TAILQ_LAST(&mountlist, mntlist); 3167 error = dounmount(mp, MNT_FORCE, td); 3168 if (error) { 3169 TAILQ_REMOVE(&mountlist, mp, mnt_list); 3170 /* 3171 * XXX: Due to the way in which we mount the root 3172 * file system off of devfs, devfs will generate a 3173 * "busy" warning when we try to unmount it before 3174 * the root. Don't print a warning as a result in 3175 * order to avoid false positive errors that may 3176 * cause needless upset. 3177 */ 3178 if (strcmp(mp->mnt_vfc->vfc_name, "devfs") != 0) { 3179 printf("unmount of %s failed (", 3180 mp->mnt_stat.f_mntonname); 3181 if (error == EBUSY) 3182 printf("BUSY)\n"); 3183 else 3184 printf("%d)\n", error); 3185 } 3186 } else { 3187 /* The unmount has removed mp from the mountlist */ 3188 } 3189 } 3190 } 3191 3192 /* 3193 * perform msync on all vnodes under a mount point 3194 * the mount point must be locked. 3195 */ 3196 void 3197 vfs_msync(struct mount *mp, int flags) 3198 { 3199 struct vnode *vp, *mvp; 3200 struct vm_object *obj; 3201 3202 CTR2(KTR_VFS, "%s: mp %p", __func__, mp); 3203 MNT_ILOCK(mp); 3204 MNT_VNODE_FOREACH(vp, mp, mvp) { 3205 VI_LOCK(vp); 3206 obj = vp->v_object; 3207 if (obj != NULL && (obj->flags & OBJ_MIGHTBEDIRTY) != 0 && 3208 (flags == MNT_WAIT || VOP_ISLOCKED(vp) == 0)) { 3209 MNT_IUNLOCK(mp); 3210 if (!vget(vp, 3211 LK_EXCLUSIVE | LK_RETRY | LK_INTERLOCK, 3212 curthread)) { 3213 if (vp->v_vflag & VV_NOSYNC) { /* unlinked */ 3214 vput(vp); 3215 MNT_ILOCK(mp); 3216 continue; 3217 } 3218 3219 obj = vp->v_object; 3220 if (obj != NULL) { 3221 VM_OBJECT_LOCK(obj); 3222 vm_object_page_clean(obj, 0, 0, 3223 flags == MNT_WAIT ? 3224 OBJPC_SYNC : OBJPC_NOSYNC); 3225 VM_OBJECT_UNLOCK(obj); 3226 } 3227 vput(vp); 3228 } 3229 MNT_ILOCK(mp); 3230 } else 3231 VI_UNLOCK(vp); 3232 } 3233 MNT_IUNLOCK(mp); 3234 } 3235 3236 /* 3237 * Mark a vnode as free, putting it up for recycling. 3238 */ 3239 static void 3240 vfree(struct vnode *vp) 3241 { 3242 3243 ASSERT_VI_LOCKED(vp, "vfree"); 3244 mtx_lock(&vnode_free_list_mtx); 3245 VNASSERT(vp->v_op != NULL, vp, ("vfree: vnode already reclaimed.")); 3246 VNASSERT((vp->v_iflag & VI_FREE) == 0, vp, ("vnode already free")); 3247 VNASSERT(VSHOULDFREE(vp), vp, ("vfree: freeing when we shouldn't")); 3248 VNASSERT((vp->v_iflag & VI_DOOMED) == 0, vp, 3249 ("vfree: Freeing doomed vnode")); 3250 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 3251 if (vp->v_iflag & VI_AGE) { 3252 TAILQ_INSERT_HEAD(&vnode_free_list, vp, v_freelist); 3253 } else { 3254 TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_freelist); 3255 } 3256 freevnodes++; 3257 vp->v_iflag &= ~VI_AGE; 3258 vp->v_iflag |= VI_FREE; 3259 mtx_unlock(&vnode_free_list_mtx); 3260 } 3261 3262 /* 3263 * Opposite of vfree() - mark a vnode as in use. 3264 */ 3265 static void 3266 vbusy(struct vnode *vp) 3267 { 3268 ASSERT_VI_LOCKED(vp, "vbusy"); 3269 VNASSERT((vp->v_iflag & VI_FREE) != 0, vp, ("vnode not free")); 3270 VNASSERT(vp->v_op != NULL, vp, ("vbusy: vnode already reclaimed.")); 3271 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 3272 3273 mtx_lock(&vnode_free_list_mtx); 3274 TAILQ_REMOVE(&vnode_free_list, vp, v_freelist); 3275 freevnodes--; 3276 vp->v_iflag &= ~(VI_FREE|VI_AGE); 3277 mtx_unlock(&vnode_free_list_mtx); 3278 } 3279 3280 static void 3281 destroy_vpollinfo(struct vpollinfo *vi) 3282 { 3283 knlist_destroy(&vi->vpi_selinfo.si_note); 3284 mtx_destroy(&vi->vpi_lock); 3285 uma_zfree(vnodepoll_zone, vi); 3286 } 3287 3288 /* 3289 * Initalize per-vnode helper structure to hold poll-related state. 3290 */ 3291 void 3292 v_addpollinfo(struct vnode *vp) 3293 { 3294 struct vpollinfo *vi; 3295 3296 if (vp->v_pollinfo != NULL) 3297 return; 3298 vi = uma_zalloc(vnodepoll_zone, M_WAITOK); 3299 mtx_init(&vi->vpi_lock, "vnode pollinfo", NULL, MTX_DEF); 3300 knlist_init(&vi->vpi_selinfo.si_note, vp, vfs_knllock, 3301 vfs_knlunlock, vfs_knl_assert_locked, vfs_knl_assert_unlocked); 3302 VI_LOCK(vp); 3303 if (vp->v_pollinfo != NULL) { 3304 VI_UNLOCK(vp); 3305 destroy_vpollinfo(vi); 3306 return; 3307 } 3308 vp->v_pollinfo = vi; 3309 VI_UNLOCK(vp); 3310 } 3311 3312 /* 3313 * Record a process's interest in events which might happen to 3314 * a vnode. Because poll uses the historic select-style interface 3315 * internally, this routine serves as both the ``check for any 3316 * pending events'' and the ``record my interest in future events'' 3317 * functions. (These are done together, while the lock is held, 3318 * to avoid race conditions.) 3319 */ 3320 int 3321 vn_pollrecord(struct vnode *vp, struct thread *td, int events) 3322 { 3323 3324 v_addpollinfo(vp); 3325 mtx_lock(&vp->v_pollinfo->vpi_lock); 3326 if (vp->v_pollinfo->vpi_revents & events) { 3327 /* 3328 * This leaves events we are not interested 3329 * in available for the other process which 3330 * which presumably had requested them 3331 * (otherwise they would never have been 3332 * recorded). 3333 */ 3334 events &= vp->v_pollinfo->vpi_revents; 3335 vp->v_pollinfo->vpi_revents &= ~events; 3336 3337 mtx_unlock(&vp->v_pollinfo->vpi_lock); 3338 return (events); 3339 } 3340 vp->v_pollinfo->vpi_events |= events; 3341 selrecord(td, &vp->v_pollinfo->vpi_selinfo); 3342 mtx_unlock(&vp->v_pollinfo->vpi_lock); 3343 return (0); 3344 } 3345 3346 /* 3347 * Routine to create and manage a filesystem syncer vnode. 3348 */ 3349 #define sync_close ((int (*)(struct vop_close_args *))nullop) 3350 static int sync_fsync(struct vop_fsync_args *); 3351 static int sync_inactive(struct vop_inactive_args *); 3352 static int sync_reclaim(struct vop_reclaim_args *); 3353 3354 static struct vop_vector sync_vnodeops = { 3355 .vop_bypass = VOP_EOPNOTSUPP, 3356 .vop_close = sync_close, /* close */ 3357 .vop_fsync = sync_fsync, /* fsync */ 3358 .vop_inactive = sync_inactive, /* inactive */ 3359 .vop_reclaim = sync_reclaim, /* reclaim */ 3360 .vop_lock1 = vop_stdlock, /* lock */ 3361 .vop_unlock = vop_stdunlock, /* unlock */ 3362 .vop_islocked = vop_stdislocked, /* islocked */ 3363 }; 3364 3365 /* 3366 * Create a new filesystem syncer vnode for the specified mount point. 3367 */ 3368 int 3369 vfs_allocate_syncvnode(struct mount *mp) 3370 { 3371 struct vnode *vp; 3372 struct bufobj *bo; 3373 static long start, incr, next; 3374 int error; 3375 3376 /* Allocate a new vnode */ 3377 if ((error = getnewvnode("syncer", mp, &sync_vnodeops, &vp)) != 0) { 3378 mp->mnt_syncer = NULL; 3379 return (error); 3380 } 3381 vp->v_type = VNON; 3382 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 3383 vp->v_vflag |= VV_FORCEINSMQ; 3384 error = insmntque(vp, mp); 3385 if (error != 0) 3386 panic("vfs_allocate_syncvnode: insmntque failed"); 3387 vp->v_vflag &= ~VV_FORCEINSMQ; 3388 VOP_UNLOCK(vp, 0); 3389 /* 3390 * Place the vnode onto the syncer worklist. We attempt to 3391 * scatter them about on the list so that they will go off 3392 * at evenly distributed times even if all the filesystems 3393 * are mounted at once. 3394 */ 3395 next += incr; 3396 if (next == 0 || next > syncer_maxdelay) { 3397 start /= 2; 3398 incr /= 2; 3399 if (start == 0) { 3400 start = syncer_maxdelay / 2; 3401 incr = syncer_maxdelay; 3402 } 3403 next = start; 3404 } 3405 bo = &vp->v_bufobj; 3406 BO_LOCK(bo); 3407 vn_syncer_add_to_worklist(bo, syncdelay > 0 ? next % syncdelay : 0); 3408 /* XXX - vn_syncer_add_to_worklist() also grabs and drops sync_mtx. */ 3409 mtx_lock(&sync_mtx); 3410 sync_vnode_count++; 3411 mtx_unlock(&sync_mtx); 3412 BO_UNLOCK(bo); 3413 mp->mnt_syncer = vp; 3414 return (0); 3415 } 3416 3417 /* 3418 * Do a lazy sync of the filesystem. 3419 */ 3420 static int 3421 sync_fsync(struct vop_fsync_args *ap) 3422 { 3423 struct vnode *syncvp = ap->a_vp; 3424 struct mount *mp = syncvp->v_mount; 3425 int error; 3426 struct bufobj *bo; 3427 3428 /* 3429 * We only need to do something if this is a lazy evaluation. 3430 */ 3431 if (ap->a_waitfor != MNT_LAZY) 3432 return (0); 3433 3434 /* 3435 * Move ourselves to the back of the sync list. 3436 */ 3437 bo = &syncvp->v_bufobj; 3438 BO_LOCK(bo); 3439 vn_syncer_add_to_worklist(bo, syncdelay); 3440 BO_UNLOCK(bo); 3441 3442 /* 3443 * Walk the list of vnodes pushing all that are dirty and 3444 * not already on the sync list. 3445 */ 3446 mtx_lock(&mountlist_mtx); 3447 if (vfs_busy(mp, MBF_NOWAIT | MBF_MNTLSTLOCK) != 0) { 3448 mtx_unlock(&mountlist_mtx); 3449 return (0); 3450 } 3451 if (vn_start_write(NULL, &mp, V_NOWAIT) != 0) { 3452 vfs_unbusy(mp); 3453 return (0); 3454 } 3455 MNT_ILOCK(mp); 3456 mp->mnt_noasync++; 3457 mp->mnt_kern_flag &= ~MNTK_ASYNC; 3458 MNT_IUNLOCK(mp); 3459 vfs_msync(mp, MNT_NOWAIT); 3460 error = VFS_SYNC(mp, MNT_LAZY); 3461 MNT_ILOCK(mp); 3462 mp->mnt_noasync--; 3463 if ((mp->mnt_flag & MNT_ASYNC) != 0 && mp->mnt_noasync == 0) 3464 mp->mnt_kern_flag |= MNTK_ASYNC; 3465 MNT_IUNLOCK(mp); 3466 vn_finished_write(mp); 3467 vfs_unbusy(mp); 3468 return (error); 3469 } 3470 3471 /* 3472 * The syncer vnode is no referenced. 3473 */ 3474 static int 3475 sync_inactive(struct vop_inactive_args *ap) 3476 { 3477 3478 vgone(ap->a_vp); 3479 return (0); 3480 } 3481 3482 /* 3483 * The syncer vnode is no longer needed and is being decommissioned. 3484 * 3485 * Modifications to the worklist must be protected by sync_mtx. 3486 */ 3487 static int 3488 sync_reclaim(struct vop_reclaim_args *ap) 3489 { 3490 struct vnode *vp = ap->a_vp; 3491 struct bufobj *bo; 3492 3493 bo = &vp->v_bufobj; 3494 BO_LOCK(bo); 3495 vp->v_mount->mnt_syncer = NULL; 3496 if (bo->bo_flag & BO_ONWORKLST) { 3497 mtx_lock(&sync_mtx); 3498 LIST_REMOVE(bo, bo_synclist); 3499 syncer_worklist_len--; 3500 sync_vnode_count--; 3501 mtx_unlock(&sync_mtx); 3502 bo->bo_flag &= ~BO_ONWORKLST; 3503 } 3504 BO_UNLOCK(bo); 3505 3506 return (0); 3507 } 3508 3509 /* 3510 * Check if vnode represents a disk device 3511 */ 3512 int 3513 vn_isdisk(struct vnode *vp, int *errp) 3514 { 3515 int error; 3516 3517 error = 0; 3518 dev_lock(); 3519 if (vp->v_type != VCHR) 3520 error = ENOTBLK; 3521 else if (vp->v_rdev == NULL) 3522 error = ENXIO; 3523 else if (vp->v_rdev->si_devsw == NULL) 3524 error = ENXIO; 3525 else if (!(vp->v_rdev->si_devsw->d_flags & D_DISK)) 3526 error = ENOTBLK; 3527 dev_unlock(); 3528 if (errp != NULL) 3529 *errp = error; 3530 return (error == 0); 3531 } 3532 3533 /* 3534 * Common filesystem object access control check routine. Accepts a 3535 * vnode's type, "mode", uid and gid, requested access mode, credentials, 3536 * and optional call-by-reference privused argument allowing vaccess() 3537 * to indicate to the caller whether privilege was used to satisfy the 3538 * request (obsoleted). Returns 0 on success, or an errno on failure. 3539 * 3540 * The ifdef'd CAPABILITIES version is here for reference, but is not 3541 * actually used. 3542 */ 3543 int 3544 vaccess(enum vtype type, mode_t file_mode, uid_t file_uid, gid_t file_gid, 3545 accmode_t accmode, struct ucred *cred, int *privused) 3546 { 3547 accmode_t dac_granted; 3548 accmode_t priv_granted; 3549 3550 KASSERT((accmode & ~(VEXEC | VWRITE | VREAD | VADMIN | VAPPEND)) == 0, 3551 ("invalid bit in accmode")); 3552 KASSERT((accmode & VAPPEND) == 0 || (accmode & VWRITE), 3553 ("VAPPEND without VWRITE")); 3554 3555 /* 3556 * Look for a normal, non-privileged way to access the file/directory 3557 * as requested. If it exists, go with that. 3558 */ 3559 3560 if (privused != NULL) 3561 *privused = 0; 3562 3563 dac_granted = 0; 3564 3565 /* Check the owner. */ 3566 if (cred->cr_uid == file_uid) { 3567 dac_granted |= VADMIN; 3568 if (file_mode & S_IXUSR) 3569 dac_granted |= VEXEC; 3570 if (file_mode & S_IRUSR) 3571 dac_granted |= VREAD; 3572 if (file_mode & S_IWUSR) 3573 dac_granted |= (VWRITE | VAPPEND); 3574 3575 if ((accmode & dac_granted) == accmode) 3576 return (0); 3577 3578 goto privcheck; 3579 } 3580 3581 /* Otherwise, check the groups (first match) */ 3582 if (groupmember(file_gid, cred)) { 3583 if (file_mode & S_IXGRP) 3584 dac_granted |= VEXEC; 3585 if (file_mode & S_IRGRP) 3586 dac_granted |= VREAD; 3587 if (file_mode & S_IWGRP) 3588 dac_granted |= (VWRITE | VAPPEND); 3589 3590 if ((accmode & dac_granted) == accmode) 3591 return (0); 3592 3593 goto privcheck; 3594 } 3595 3596 /* Otherwise, check everyone else. */ 3597 if (file_mode & S_IXOTH) 3598 dac_granted |= VEXEC; 3599 if (file_mode & S_IROTH) 3600 dac_granted |= VREAD; 3601 if (file_mode & S_IWOTH) 3602 dac_granted |= (VWRITE | VAPPEND); 3603 if ((accmode & dac_granted) == accmode) 3604 return (0); 3605 3606 privcheck: 3607 /* 3608 * Build a privilege mask to determine if the set of privileges 3609 * satisfies the requirements when combined with the granted mask 3610 * from above. For each privilege, if the privilege is required, 3611 * bitwise or the request type onto the priv_granted mask. 3612 */ 3613 priv_granted = 0; 3614 3615 if (type == VDIR) { 3616 /* 3617 * For directories, use PRIV_VFS_LOOKUP to satisfy VEXEC 3618 * requests, instead of PRIV_VFS_EXEC. 3619 */ 3620 if ((accmode & VEXEC) && ((dac_granted & VEXEC) == 0) && 3621 !priv_check_cred(cred, PRIV_VFS_LOOKUP, 0)) 3622 priv_granted |= VEXEC; 3623 } else { 3624 if ((accmode & VEXEC) && ((dac_granted & VEXEC) == 0) && 3625 !priv_check_cred(cred, PRIV_VFS_EXEC, 0)) 3626 priv_granted |= VEXEC; 3627 } 3628 3629 if ((accmode & VREAD) && ((dac_granted & VREAD) == 0) && 3630 !priv_check_cred(cred, PRIV_VFS_READ, 0)) 3631 priv_granted |= VREAD; 3632 3633 if ((accmode & VWRITE) && ((dac_granted & VWRITE) == 0) && 3634 !priv_check_cred(cred, PRIV_VFS_WRITE, 0)) 3635 priv_granted |= (VWRITE | VAPPEND); 3636 3637 if ((accmode & VADMIN) && ((dac_granted & VADMIN) == 0) && 3638 !priv_check_cred(cred, PRIV_VFS_ADMIN, 0)) 3639 priv_granted |= VADMIN; 3640 3641 if ((accmode & (priv_granted | dac_granted)) == accmode) { 3642 /* XXX audit: privilege used */ 3643 if (privused != NULL) 3644 *privused = 1; 3645 return (0); 3646 } 3647 3648 return ((accmode & VADMIN) ? EPERM : EACCES); 3649 } 3650 3651 /* 3652 * Credential check based on process requesting service, and per-attribute 3653 * permissions. 3654 */ 3655 int 3656 extattr_check_cred(struct vnode *vp, int attrnamespace, struct ucred *cred, 3657 struct thread *td, accmode_t accmode) 3658 { 3659 3660 /* 3661 * Kernel-invoked always succeeds. 3662 */ 3663 if (cred == NOCRED) 3664 return (0); 3665 3666 /* 3667 * Do not allow privileged processes in jail to directly manipulate 3668 * system attributes. 3669 */ 3670 switch (attrnamespace) { 3671 case EXTATTR_NAMESPACE_SYSTEM: 3672 /* Potentially should be: return (EPERM); */ 3673 return (priv_check_cred(cred, PRIV_VFS_EXTATTR_SYSTEM, 0)); 3674 case EXTATTR_NAMESPACE_USER: 3675 return (VOP_ACCESS(vp, accmode, cred, td)); 3676 default: 3677 return (EPERM); 3678 } 3679 } 3680 3681 #ifdef DEBUG_VFS_LOCKS 3682 /* 3683 * This only exists to supress warnings from unlocked specfs accesses. It is 3684 * no longer ok to have an unlocked VFS. 3685 */ 3686 #define IGNORE_LOCK(vp) (panicstr != NULL || (vp) == NULL || \ 3687 (vp)->v_type == VCHR || (vp)->v_type == VBAD) 3688 3689 int vfs_badlock_ddb = 1; /* Drop into debugger on violation. */ 3690 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_ddb, CTLFLAG_RW, &vfs_badlock_ddb, 0, ""); 3691 3692 int vfs_badlock_mutex = 1; /* Check for interlock across VOPs. */ 3693 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_mutex, CTLFLAG_RW, &vfs_badlock_mutex, 0, ""); 3694 3695 int vfs_badlock_print = 1; /* Print lock violations. */ 3696 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_print, CTLFLAG_RW, &vfs_badlock_print, 0, ""); 3697 3698 #ifdef KDB 3699 int vfs_badlock_backtrace = 1; /* Print backtrace at lock violations. */ 3700 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_backtrace, CTLFLAG_RW, &vfs_badlock_backtrace, 0, ""); 3701 #endif 3702 3703 static void 3704 vfs_badlock(const char *msg, const char *str, struct vnode *vp) 3705 { 3706 3707 #ifdef KDB 3708 if (vfs_badlock_backtrace) 3709 kdb_backtrace(); 3710 #endif 3711 if (vfs_badlock_print) 3712 printf("%s: %p %s\n", str, (void *)vp, msg); 3713 if (vfs_badlock_ddb) 3714 kdb_enter(KDB_WHY_VFSLOCK, "lock violation"); 3715 } 3716 3717 void 3718 assert_vi_locked(struct vnode *vp, const char *str) 3719 { 3720 3721 if (vfs_badlock_mutex && !mtx_owned(VI_MTX(vp))) 3722 vfs_badlock("interlock is not locked but should be", str, vp); 3723 } 3724 3725 void 3726 assert_vi_unlocked(struct vnode *vp, const char *str) 3727 { 3728 3729 if (vfs_badlock_mutex && mtx_owned(VI_MTX(vp))) 3730 vfs_badlock("interlock is locked but should not be", str, vp); 3731 } 3732 3733 void 3734 assert_vop_locked(struct vnode *vp, const char *str) 3735 { 3736 3737 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) == 0) 3738 vfs_badlock("is not locked but should be", str, vp); 3739 } 3740 3741 void 3742 assert_vop_unlocked(struct vnode *vp, const char *str) 3743 { 3744 3745 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) == LK_EXCLUSIVE) 3746 vfs_badlock("is locked but should not be", str, vp); 3747 } 3748 3749 void 3750 assert_vop_elocked(struct vnode *vp, const char *str) 3751 { 3752 3753 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) != LK_EXCLUSIVE) 3754 vfs_badlock("is not exclusive locked but should be", str, vp); 3755 } 3756 3757 #if 0 3758 void 3759 assert_vop_elocked_other(struct vnode *vp, const char *str) 3760 { 3761 3762 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) != LK_EXCLOTHER) 3763 vfs_badlock("is not exclusive locked by another thread", 3764 str, vp); 3765 } 3766 3767 void 3768 assert_vop_slocked(struct vnode *vp, const char *str) 3769 { 3770 3771 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) != LK_SHARED) 3772 vfs_badlock("is not locked shared but should be", str, vp); 3773 } 3774 #endif /* 0 */ 3775 #endif /* DEBUG_VFS_LOCKS */ 3776 3777 void 3778 vop_rename_fail(struct vop_rename_args *ap) 3779 { 3780 3781 if (ap->a_tvp != NULL) 3782 vput(ap->a_tvp); 3783 if (ap->a_tdvp == ap->a_tvp) 3784 vrele(ap->a_tdvp); 3785 else 3786 vput(ap->a_tdvp); 3787 vrele(ap->a_fdvp); 3788 vrele(ap->a_fvp); 3789 } 3790 3791 void 3792 vop_rename_pre(void *ap) 3793 { 3794 struct vop_rename_args *a = ap; 3795 3796 #ifdef DEBUG_VFS_LOCKS 3797 if (a->a_tvp) 3798 ASSERT_VI_UNLOCKED(a->a_tvp, "VOP_RENAME"); 3799 ASSERT_VI_UNLOCKED(a->a_tdvp, "VOP_RENAME"); 3800 ASSERT_VI_UNLOCKED(a->a_fvp, "VOP_RENAME"); 3801 ASSERT_VI_UNLOCKED(a->a_fdvp, "VOP_RENAME"); 3802 3803 /* Check the source (from). */ 3804 if (a->a_tdvp->v_vnlock != a->a_fdvp->v_vnlock && 3805 (a->a_tvp == NULL || a->a_tvp->v_vnlock != a->a_fdvp->v_vnlock)) 3806 ASSERT_VOP_UNLOCKED(a->a_fdvp, "vop_rename: fdvp locked"); 3807 if (a->a_tvp == NULL || a->a_tvp->v_vnlock != a->a_fvp->v_vnlock) 3808 ASSERT_VOP_UNLOCKED(a->a_fvp, "vop_rename: fvp locked"); 3809 3810 /* Check the target. */ 3811 if (a->a_tvp) 3812 ASSERT_VOP_LOCKED(a->a_tvp, "vop_rename: tvp not locked"); 3813 ASSERT_VOP_LOCKED(a->a_tdvp, "vop_rename: tdvp not locked"); 3814 #endif 3815 if (a->a_tdvp != a->a_fdvp) 3816 vhold(a->a_fdvp); 3817 if (a->a_tvp != a->a_fvp) 3818 vhold(a->a_fvp); 3819 vhold(a->a_tdvp); 3820 if (a->a_tvp) 3821 vhold(a->a_tvp); 3822 } 3823 3824 void 3825 vop_strategy_pre(void *ap) 3826 { 3827 #ifdef DEBUG_VFS_LOCKS 3828 struct vop_strategy_args *a; 3829 struct buf *bp; 3830 3831 a = ap; 3832 bp = a->a_bp; 3833 3834 /* 3835 * Cluster ops lock their component buffers but not the IO container. 3836 */ 3837 if ((bp->b_flags & B_CLUSTER) != 0) 3838 return; 3839 3840 if (!BUF_ISLOCKED(bp)) { 3841 if (vfs_badlock_print) 3842 printf( 3843 "VOP_STRATEGY: bp is not locked but should be\n"); 3844 if (vfs_badlock_ddb) 3845 kdb_enter(KDB_WHY_VFSLOCK, "lock violation"); 3846 } 3847 #endif 3848 } 3849 3850 void 3851 vop_lookup_pre(void *ap) 3852 { 3853 #ifdef DEBUG_VFS_LOCKS 3854 struct vop_lookup_args *a; 3855 struct vnode *dvp; 3856 3857 a = ap; 3858 dvp = a->a_dvp; 3859 ASSERT_VI_UNLOCKED(dvp, "VOP_LOOKUP"); 3860 ASSERT_VOP_LOCKED(dvp, "VOP_LOOKUP"); 3861 #endif 3862 } 3863 3864 void 3865 vop_lookup_post(void *ap, int rc) 3866 { 3867 #ifdef DEBUG_VFS_LOCKS 3868 struct vop_lookup_args *a; 3869 struct vnode *dvp; 3870 struct vnode *vp; 3871 3872 a = ap; 3873 dvp = a->a_dvp; 3874 vp = *(a->a_vpp); 3875 3876 ASSERT_VI_UNLOCKED(dvp, "VOP_LOOKUP"); 3877 ASSERT_VOP_LOCKED(dvp, "VOP_LOOKUP"); 3878 3879 if (!rc) 3880 ASSERT_VOP_LOCKED(vp, "VOP_LOOKUP (child)"); 3881 #endif 3882 } 3883 3884 void 3885 vop_lock_pre(void *ap) 3886 { 3887 #ifdef DEBUG_VFS_LOCKS 3888 struct vop_lock1_args *a = ap; 3889 3890 if ((a->a_flags & LK_INTERLOCK) == 0) 3891 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_LOCK"); 3892 else 3893 ASSERT_VI_LOCKED(a->a_vp, "VOP_LOCK"); 3894 #endif 3895 } 3896 3897 void 3898 vop_lock_post(void *ap, int rc) 3899 { 3900 #ifdef DEBUG_VFS_LOCKS 3901 struct vop_lock1_args *a = ap; 3902 3903 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_LOCK"); 3904 if (rc == 0) 3905 ASSERT_VOP_LOCKED(a->a_vp, "VOP_LOCK"); 3906 #endif 3907 } 3908 3909 void 3910 vop_unlock_pre(void *ap) 3911 { 3912 #ifdef DEBUG_VFS_LOCKS 3913 struct vop_unlock_args *a = ap; 3914 3915 if (a->a_flags & LK_INTERLOCK) 3916 ASSERT_VI_LOCKED(a->a_vp, "VOP_UNLOCK"); 3917 ASSERT_VOP_LOCKED(a->a_vp, "VOP_UNLOCK"); 3918 #endif 3919 } 3920 3921 void 3922 vop_unlock_post(void *ap, int rc) 3923 { 3924 #ifdef DEBUG_VFS_LOCKS 3925 struct vop_unlock_args *a = ap; 3926 3927 if (a->a_flags & LK_INTERLOCK) 3928 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_UNLOCK"); 3929 #endif 3930 } 3931 3932 void 3933 vop_create_post(void *ap, int rc) 3934 { 3935 struct vop_create_args *a = ap; 3936 3937 if (!rc) 3938 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 3939 } 3940 3941 void 3942 vop_link_post(void *ap, int rc) 3943 { 3944 struct vop_link_args *a = ap; 3945 3946 if (!rc) { 3947 VFS_KNOTE_LOCKED(a->a_vp, NOTE_LINK); 3948 VFS_KNOTE_LOCKED(a->a_tdvp, NOTE_WRITE); 3949 } 3950 } 3951 3952 void 3953 vop_mkdir_post(void *ap, int rc) 3954 { 3955 struct vop_mkdir_args *a = ap; 3956 3957 if (!rc) 3958 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE | NOTE_LINK); 3959 } 3960 3961 void 3962 vop_mknod_post(void *ap, int rc) 3963 { 3964 struct vop_mknod_args *a = ap; 3965 3966 if (!rc) 3967 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 3968 } 3969 3970 void 3971 vop_remove_post(void *ap, int rc) 3972 { 3973 struct vop_remove_args *a = ap; 3974 3975 if (!rc) { 3976 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 3977 VFS_KNOTE_LOCKED(a->a_vp, NOTE_DELETE); 3978 } 3979 } 3980 3981 void 3982 vop_rename_post(void *ap, int rc) 3983 { 3984 struct vop_rename_args *a = ap; 3985 3986 if (!rc) { 3987 VFS_KNOTE_UNLOCKED(a->a_fdvp, NOTE_WRITE); 3988 VFS_KNOTE_UNLOCKED(a->a_tdvp, NOTE_WRITE); 3989 VFS_KNOTE_UNLOCKED(a->a_fvp, NOTE_RENAME); 3990 if (a->a_tvp) 3991 VFS_KNOTE_UNLOCKED(a->a_tvp, NOTE_DELETE); 3992 } 3993 if (a->a_tdvp != a->a_fdvp) 3994 vdrop(a->a_fdvp); 3995 if (a->a_tvp != a->a_fvp) 3996 vdrop(a->a_fvp); 3997 vdrop(a->a_tdvp); 3998 if (a->a_tvp) 3999 vdrop(a->a_tvp); 4000 } 4001 4002 void 4003 vop_rmdir_post(void *ap, int rc) 4004 { 4005 struct vop_rmdir_args *a = ap; 4006 4007 if (!rc) { 4008 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE | NOTE_LINK); 4009 VFS_KNOTE_LOCKED(a->a_vp, NOTE_DELETE); 4010 } 4011 } 4012 4013 void 4014 vop_setattr_post(void *ap, int rc) 4015 { 4016 struct vop_setattr_args *a = ap; 4017 4018 if (!rc) 4019 VFS_KNOTE_LOCKED(a->a_vp, NOTE_ATTRIB); 4020 } 4021 4022 void 4023 vop_symlink_post(void *ap, int rc) 4024 { 4025 struct vop_symlink_args *a = ap; 4026 4027 if (!rc) 4028 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 4029 } 4030 4031 static struct knlist fs_knlist; 4032 4033 static void 4034 vfs_event_init(void *arg) 4035 { 4036 knlist_init_mtx(&fs_knlist, NULL); 4037 } 4038 /* XXX - correct order? */ 4039 SYSINIT(vfs_knlist, SI_SUB_VFS, SI_ORDER_ANY, vfs_event_init, NULL); 4040 4041 void 4042 vfs_event_signal(fsid_t *fsid, uint32_t event, intptr_t data __unused) 4043 { 4044 4045 KNOTE_UNLOCKED(&fs_knlist, event); 4046 } 4047 4048 static int filt_fsattach(struct knote *kn); 4049 static void filt_fsdetach(struct knote *kn); 4050 static int filt_fsevent(struct knote *kn, long hint); 4051 4052 struct filterops fs_filtops = { 4053 .f_isfd = 0, 4054 .f_attach = filt_fsattach, 4055 .f_detach = filt_fsdetach, 4056 .f_event = filt_fsevent 4057 }; 4058 4059 static int 4060 filt_fsattach(struct knote *kn) 4061 { 4062 4063 kn->kn_flags |= EV_CLEAR; 4064 knlist_add(&fs_knlist, kn, 0); 4065 return (0); 4066 } 4067 4068 static void 4069 filt_fsdetach(struct knote *kn) 4070 { 4071 4072 knlist_remove(&fs_knlist, kn, 0); 4073 } 4074 4075 static int 4076 filt_fsevent(struct knote *kn, long hint) 4077 { 4078 4079 kn->kn_fflags |= hint; 4080 return (kn->kn_fflags != 0); 4081 } 4082 4083 static int 4084 sysctl_vfs_ctl(SYSCTL_HANDLER_ARGS) 4085 { 4086 struct vfsidctl vc; 4087 int error; 4088 struct mount *mp; 4089 4090 error = SYSCTL_IN(req, &vc, sizeof(vc)); 4091 if (error) 4092 return (error); 4093 if (vc.vc_vers != VFS_CTL_VERS1) 4094 return (EINVAL); 4095 mp = vfs_getvfs(&vc.vc_fsid); 4096 if (mp == NULL) 4097 return (ENOENT); 4098 /* ensure that a specific sysctl goes to the right filesystem. */ 4099 if (strcmp(vc.vc_fstypename, "*") != 0 && 4100 strcmp(vc.vc_fstypename, mp->mnt_vfc->vfc_name) != 0) { 4101 vfs_rel(mp); 4102 return (EINVAL); 4103 } 4104 VCTLTOREQ(&vc, req); 4105 error = VFS_SYSCTL(mp, vc.vc_op, req); 4106 vfs_rel(mp); 4107 return (error); 4108 } 4109 4110 SYSCTL_PROC(_vfs, OID_AUTO, ctl, CTLFLAG_WR, NULL, 0, sysctl_vfs_ctl, "", 4111 "Sysctl by fsid"); 4112 4113 /* 4114 * Function to initialize a va_filerev field sensibly. 4115 * XXX: Wouldn't a random number make a lot more sense ?? 4116 */ 4117 u_quad_t 4118 init_va_filerev(void) 4119 { 4120 struct bintime bt; 4121 4122 getbinuptime(&bt); 4123 return (((u_quad_t)bt.sec << 32LL) | (bt.frac >> 32LL)); 4124 } 4125 4126 static int filt_vfsread(struct knote *kn, long hint); 4127 static int filt_vfswrite(struct knote *kn, long hint); 4128 static int filt_vfsvnode(struct knote *kn, long hint); 4129 static void filt_vfsdetach(struct knote *kn); 4130 static struct filterops vfsread_filtops = { 4131 .f_isfd = 1, 4132 .f_detach = filt_vfsdetach, 4133 .f_event = filt_vfsread 4134 }; 4135 static struct filterops vfswrite_filtops = { 4136 .f_isfd = 1, 4137 .f_detach = filt_vfsdetach, 4138 .f_event = filt_vfswrite 4139 }; 4140 static struct filterops vfsvnode_filtops = { 4141 .f_isfd = 1, 4142 .f_detach = filt_vfsdetach, 4143 .f_event = filt_vfsvnode 4144 }; 4145 4146 static void 4147 vfs_knllock(void *arg) 4148 { 4149 struct vnode *vp = arg; 4150 4151 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 4152 } 4153 4154 static void 4155 vfs_knlunlock(void *arg) 4156 { 4157 struct vnode *vp = arg; 4158 4159 VOP_UNLOCK(vp, 0); 4160 } 4161 4162 static void 4163 vfs_knl_assert_locked(void *arg) 4164 { 4165 #ifdef DEBUG_VFS_LOCKS 4166 struct vnode *vp = arg; 4167 4168 ASSERT_VOP_LOCKED(vp, "vfs_knl_assert_locked"); 4169 #endif 4170 } 4171 4172 static void 4173 vfs_knl_assert_unlocked(void *arg) 4174 { 4175 #ifdef DEBUG_VFS_LOCKS 4176 struct vnode *vp = arg; 4177 4178 ASSERT_VOP_UNLOCKED(vp, "vfs_knl_assert_unlocked"); 4179 #endif 4180 } 4181 4182 int 4183 vfs_kqfilter(struct vop_kqfilter_args *ap) 4184 { 4185 struct vnode *vp = ap->a_vp; 4186 struct knote *kn = ap->a_kn; 4187 struct knlist *knl; 4188 4189 switch (kn->kn_filter) { 4190 case EVFILT_READ: 4191 kn->kn_fop = &vfsread_filtops; 4192 break; 4193 case EVFILT_WRITE: 4194 kn->kn_fop = &vfswrite_filtops; 4195 break; 4196 case EVFILT_VNODE: 4197 kn->kn_fop = &vfsvnode_filtops; 4198 break; 4199 default: 4200 return (EINVAL); 4201 } 4202 4203 kn->kn_hook = (caddr_t)vp; 4204 4205 v_addpollinfo(vp); 4206 if (vp->v_pollinfo == NULL) 4207 return (ENOMEM); 4208 knl = &vp->v_pollinfo->vpi_selinfo.si_note; 4209 knlist_add(knl, kn, 0); 4210 4211 return (0); 4212 } 4213 4214 /* 4215 * Detach knote from vnode 4216 */ 4217 static void 4218 filt_vfsdetach(struct knote *kn) 4219 { 4220 struct vnode *vp = (struct vnode *)kn->kn_hook; 4221 4222 KASSERT(vp->v_pollinfo != NULL, ("Missing v_pollinfo")); 4223 knlist_remove(&vp->v_pollinfo->vpi_selinfo.si_note, kn, 0); 4224 } 4225 4226 /*ARGSUSED*/ 4227 static int 4228 filt_vfsread(struct knote *kn, long hint) 4229 { 4230 struct vnode *vp = (struct vnode *)kn->kn_hook; 4231 struct vattr va; 4232 int res; 4233 4234 /* 4235 * filesystem is gone, so set the EOF flag and schedule 4236 * the knote for deletion. 4237 */ 4238 if (hint == NOTE_REVOKE) { 4239 VI_LOCK(vp); 4240 kn->kn_flags |= (EV_EOF | EV_ONESHOT); 4241 VI_UNLOCK(vp); 4242 return (1); 4243 } 4244 4245 if (VOP_GETATTR(vp, &va, curthread->td_ucred)) 4246 return (0); 4247 4248 VI_LOCK(vp); 4249 kn->kn_data = va.va_size - kn->kn_fp->f_offset; 4250 res = (kn->kn_data != 0); 4251 VI_UNLOCK(vp); 4252 return (res); 4253 } 4254 4255 /*ARGSUSED*/ 4256 static int 4257 filt_vfswrite(struct knote *kn, long hint) 4258 { 4259 struct vnode *vp = (struct vnode *)kn->kn_hook; 4260 4261 VI_LOCK(vp); 4262 4263 /* 4264 * filesystem is gone, so set the EOF flag and schedule 4265 * the knote for deletion. 4266 */ 4267 if (hint == NOTE_REVOKE) 4268 kn->kn_flags |= (EV_EOF | EV_ONESHOT); 4269 4270 kn->kn_data = 0; 4271 VI_UNLOCK(vp); 4272 return (1); 4273 } 4274 4275 static int 4276 filt_vfsvnode(struct knote *kn, long hint) 4277 { 4278 struct vnode *vp = (struct vnode *)kn->kn_hook; 4279 int res; 4280 4281 VI_LOCK(vp); 4282 if (kn->kn_sfflags & hint) 4283 kn->kn_fflags |= hint; 4284 if (hint == NOTE_REVOKE) { 4285 kn->kn_flags |= EV_EOF; 4286 VI_UNLOCK(vp); 4287 return (1); 4288 } 4289 res = (kn->kn_fflags != 0); 4290 VI_UNLOCK(vp); 4291 return (res); 4292 } 4293 4294 int 4295 vfs_read_dirent(struct vop_readdir_args *ap, struct dirent *dp, off_t off) 4296 { 4297 int error; 4298 4299 if (dp->d_reclen > ap->a_uio->uio_resid) 4300 return (ENAMETOOLONG); 4301 error = uiomove(dp, dp->d_reclen, ap->a_uio); 4302 if (error) { 4303 if (ap->a_ncookies != NULL) { 4304 if (ap->a_cookies != NULL) 4305 free(ap->a_cookies, M_TEMP); 4306 ap->a_cookies = NULL; 4307 *ap->a_ncookies = 0; 4308 } 4309 return (error); 4310 } 4311 if (ap->a_ncookies == NULL) 4312 return (0); 4313 4314 KASSERT(ap->a_cookies, 4315 ("NULL ap->a_cookies value with non-NULL ap->a_ncookies!")); 4316 4317 *ap->a_cookies = realloc(*ap->a_cookies, 4318 (*ap->a_ncookies + 1) * sizeof(u_long), M_TEMP, M_WAITOK | M_ZERO); 4319 (*ap->a_cookies)[*ap->a_ncookies] = off; 4320 return (0); 4321 } 4322 4323 /* 4324 * Mark for update the access time of the file if the filesystem 4325 * supports VOP_MARKATIME. This functionality is used by execve and 4326 * mmap, so we want to avoid the I/O implied by directly setting 4327 * va_atime for the sake of efficiency. 4328 */ 4329 void 4330 vfs_mark_atime(struct vnode *vp, struct ucred *cred) 4331 { 4332 struct mount *mp; 4333 4334 mp = vp->v_mount; 4335 VFS_ASSERT_GIANT(mp); 4336 ASSERT_VOP_LOCKED(vp, "vfs_mark_atime"); 4337 if (mp != NULL && (mp->mnt_flag & (MNT_NOATIME | MNT_RDONLY)) == 0) 4338 (void)VOP_MARKATIME(vp); 4339 } 4340 4341 /* 4342 * The purpose of this routine is to remove granularity from accmode_t, 4343 * reducing it into standard unix access bits - VEXEC, VREAD, VWRITE, 4344 * VADMIN and VAPPEND. 4345 * 4346 * If it returns 0, the caller is supposed to continue with the usual 4347 * access checks using 'accmode' as modified by this routine. If it 4348 * returns nonzero value, the caller is supposed to return that value 4349 * as errno. 4350 * 4351 * Note that after this routine runs, accmode may be zero. 4352 */ 4353 int 4354 vfs_unixify_accmode(accmode_t *accmode) 4355 { 4356 /* 4357 * There is no way to specify explicit "deny" rule using 4358 * file mode or POSIX.1e ACLs. 4359 */ 4360 if (*accmode & VEXPLICIT_DENY) { 4361 *accmode = 0; 4362 return (0); 4363 } 4364 4365 /* 4366 * None of these can be translated into usual access bits. 4367 * Also, the common case for NFSv4 ACLs is to not contain 4368 * either of these bits. Caller should check for VWRITE 4369 * on the containing directory instead. 4370 */ 4371 if (*accmode & (VDELETE_CHILD | VDELETE)) 4372 return (EPERM); 4373 4374 if (*accmode & VADMIN_PERMS) { 4375 *accmode &= ~VADMIN_PERMS; 4376 *accmode |= VADMIN; 4377 } 4378 4379 /* 4380 * There is no way to deny VREAD_ATTRIBUTES, VREAD_ACL 4381 * or VSYNCHRONIZE using file mode or POSIX.1e ACL. 4382 */ 4383 *accmode &= ~(VSTAT_PERMS | VSYNCHRONIZE); 4384 4385 return (0); 4386 } 4387