1 /*- 2 * Copyright (c) 1989, 1993 3 * The Regents of the University of California. All rights reserved. 4 * (c) UNIX System Laboratories, Inc. 5 * All or some portions of this file are derived from material licensed 6 * to the University of California by American Telephone and Telegraph 7 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 8 * the permission of UNIX System Laboratories, Inc. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 4. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * @(#)vfs_subr.c 8.31 (Berkeley) 5/26/95 35 */ 36 37 /* 38 * External virtual filesystem routines 39 */ 40 41 #include <sys/cdefs.h> 42 __FBSDID("$FreeBSD$"); 43 44 #include "opt_ddb.h" 45 #include "opt_watchdog.h" 46 47 #include <sys/param.h> 48 #include <sys/systm.h> 49 #include <sys/bio.h> 50 #include <sys/buf.h> 51 #include <sys/condvar.h> 52 #include <sys/conf.h> 53 #include <sys/dirent.h> 54 #include <sys/event.h> 55 #include <sys/eventhandler.h> 56 #include <sys/extattr.h> 57 #include <sys/file.h> 58 #include <sys/fcntl.h> 59 #include <sys/jail.h> 60 #include <sys/kdb.h> 61 #include <sys/kernel.h> 62 #include <sys/kthread.h> 63 #include <sys/lockf.h> 64 #include <sys/malloc.h> 65 #include <sys/mount.h> 66 #include <sys/namei.h> 67 #include <sys/priv.h> 68 #include <sys/reboot.h> 69 #include <sys/sched.h> 70 #include <sys/sleepqueue.h> 71 #include <sys/stat.h> 72 #include <sys/sysctl.h> 73 #include <sys/syslog.h> 74 #include <sys/vmmeter.h> 75 #include <sys/vnode.h> 76 #ifdef SW_WATCHDOG 77 #include <sys/watchdog.h> 78 #endif 79 80 #include <machine/stdarg.h> 81 82 #include <security/mac/mac_framework.h> 83 84 #include <vm/vm.h> 85 #include <vm/vm_object.h> 86 #include <vm/vm_extern.h> 87 #include <vm/pmap.h> 88 #include <vm/vm_map.h> 89 #include <vm/vm_page.h> 90 #include <vm/vm_kern.h> 91 #include <vm/uma.h> 92 93 #ifdef DDB 94 #include <ddb/ddb.h> 95 #endif 96 97 #define WI_MPSAFEQ 0 98 #define WI_GIANTQ 1 99 100 static void delmntque(struct vnode *vp); 101 static int flushbuflist(struct bufv *bufv, int flags, struct bufobj *bo, 102 int slpflag, int slptimeo); 103 static void syncer_shutdown(void *arg, int howto); 104 static int vtryrecycle(struct vnode *vp); 105 static void v_incr_usecount(struct vnode *); 106 static void v_decr_usecount(struct vnode *); 107 static void v_decr_useonly(struct vnode *); 108 static void v_upgrade_usecount(struct vnode *); 109 static void 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 in vdropl() for VI_DOOMED vnode. 120 */ 121 static unsigned long numvnodes; 122 123 SYSCTL_ULONG(_vfs, OID_AUTO, numvnodes, CTLFLAG_RD, &numvnodes, 0, 124 "Number of vnodes in existence"); 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_ULONG(_vfs, OID_AUTO, wantfreevnodes, CTLFLAG_RW, &wantfreevnodes, 0, ""); 151 /* Number of vnodes in the free list. */ 152 static u_long freevnodes; 153 SYSCTL_ULONG(_vfs, OID_AUTO, freevnodes, CTLFLAG_RD, &freevnodes, 0, 154 "Number of vnodes in the free list"); 155 156 static int vlru_allow_cache_src; 157 SYSCTL_INT(_vfs, OID_AUTO, vlru_allow_cache_src, CTLFLAG_RW, 158 &vlru_allow_cache_src, 0, "Allow vlru to reclaim source vnode"); 159 160 /* 161 * Various variables used for debugging the new implementation of 162 * reassignbuf(). 163 * XXX these are probably of (very) limited utility now. 164 */ 165 static int reassignbufcalls; 166 SYSCTL_INT(_vfs, OID_AUTO, reassignbufcalls, CTLFLAG_RW, &reassignbufcalls, 0, 167 "Number of calls to reassignbuf"); 168 169 /* 170 * Cache for the mount type id assigned to NFS. This is used for 171 * special checks in nfs/nfs_nqlease.c and vm/vnode_pager.c. 172 */ 173 int nfs_mount_type = -1; 174 175 /* To keep more than one thread at a time from running vfs_getnewfsid */ 176 static struct mtx mntid_mtx; 177 178 /* 179 * Lock for any access to the following: 180 * vnode_free_list 181 * numvnodes 182 * freevnodes 183 */ 184 static struct mtx vnode_free_list_mtx; 185 186 /* Publicly exported FS */ 187 struct nfs_public nfs_pub; 188 189 /* Zone for allocation of new vnodes - used exclusively by getnewvnode() */ 190 static uma_zone_t vnode_zone; 191 static uma_zone_t vnodepoll_zone; 192 193 /* 194 * The workitem queue. 195 * 196 * It is useful to delay writes of file data and filesystem metadata 197 * for tens of seconds so that quickly created and deleted files need 198 * not waste disk bandwidth being created and removed. To realize this, 199 * we append vnodes to a "workitem" queue. When running with a soft 200 * updates implementation, most pending metadata dependencies should 201 * not wait for more than a few seconds. Thus, mounted on block devices 202 * are delayed only about a half the time that file data is delayed. 203 * Similarly, directory updates are more critical, so are only delayed 204 * about a third the time that file data is delayed. Thus, there are 205 * SYNCER_MAXDELAY queues that are processed round-robin at a rate of 206 * one each second (driven off the filesystem syncer process). The 207 * syncer_delayno variable indicates the next queue that is to be processed. 208 * Items that need to be processed soon are placed in this queue: 209 * 210 * syncer_workitem_pending[syncer_delayno] 211 * 212 * A delay of fifteen seconds is done by placing the request fifteen 213 * entries later in the queue: 214 * 215 * syncer_workitem_pending[(syncer_delayno + 15) & syncer_mask] 216 * 217 */ 218 static int syncer_delayno; 219 static long syncer_mask; 220 LIST_HEAD(synclist, bufobj); 221 static struct synclist *syncer_workitem_pending[2]; 222 /* 223 * The sync_mtx protects: 224 * bo->bo_synclist 225 * sync_vnode_count 226 * syncer_delayno 227 * syncer_state 228 * syncer_workitem_pending 229 * syncer_worklist_len 230 * rushjob 231 */ 232 static struct mtx sync_mtx; 233 static struct cv sync_wakeup; 234 235 #define SYNCER_MAXDELAY 32 236 static int syncer_maxdelay = SYNCER_MAXDELAY; /* maximum delay time */ 237 static int syncdelay = 30; /* max time to delay syncing data */ 238 static int filedelay = 30; /* time to delay syncing files */ 239 SYSCTL_INT(_kern, OID_AUTO, filedelay, CTLFLAG_RW, &filedelay, 0, 240 "Time to delay syncing files (in seconds)"); 241 static int dirdelay = 29; /* time to delay syncing directories */ 242 SYSCTL_INT(_kern, OID_AUTO, dirdelay, CTLFLAG_RW, &dirdelay, 0, 243 "Time to delay syncing directories (in seconds)"); 244 static int metadelay = 28; /* time to delay syncing metadata */ 245 SYSCTL_INT(_kern, OID_AUTO, metadelay, CTLFLAG_RW, &metadelay, 0, 246 "Time to delay syncing metadata (in seconds)"); 247 static int rushjob; /* number of slots to run ASAP */ 248 static int stat_rush_requests; /* number of times I/O speeded up */ 249 SYSCTL_INT(_debug, OID_AUTO, rush_requests, CTLFLAG_RW, &stat_rush_requests, 0, 250 "Number of times I/O speeded up (rush requests)"); 251 252 /* 253 * When shutting down the syncer, run it at four times normal speed. 254 */ 255 #define SYNCER_SHUTDOWN_SPEEDUP 4 256 static int sync_vnode_count; 257 static int syncer_worklist_len; 258 static enum { SYNCER_RUNNING, SYNCER_SHUTTING_DOWN, SYNCER_FINAL_DELAY } 259 syncer_state; 260 261 /* 262 * Number of vnodes we want to exist at any one time. This is mostly used 263 * to size hash tables in vnode-related code. It is normally not used in 264 * getnewvnode(), as wantfreevnodes is normally nonzero.) 265 * 266 * XXX desiredvnodes is historical cruft and should not exist. 267 */ 268 int desiredvnodes; 269 SYSCTL_INT(_kern, KERN_MAXVNODES, maxvnodes, CTLFLAG_RW, 270 &desiredvnodes, 0, "Maximum number of vnodes"); 271 SYSCTL_ULONG(_kern, OID_AUTO, minvnodes, CTLFLAG_RW, 272 &wantfreevnodes, 0, "Minimum number of vnodes (legacy)"); 273 static int vnlru_nowhere; 274 SYSCTL_INT(_debug, OID_AUTO, vnlru_nowhere, CTLFLAG_RW, 275 &vnlru_nowhere, 0, "Number of times the vnlru process ran without success"); 276 277 /* 278 * Macros to control when a vnode is freed and recycled. All require 279 * the vnode interlock. 280 */ 281 #define VCANRECYCLE(vp) (((vp)->v_iflag & VI_FREE) && !(vp)->v_holdcnt) 282 #define VSHOULDFREE(vp) (!((vp)->v_iflag & VI_FREE) && !(vp)->v_holdcnt) 283 #define VSHOULDBUSY(vp) (((vp)->v_iflag & VI_FREE) && (vp)->v_holdcnt) 284 285 286 /* 287 * Initialize the vnode management data structures. 288 * 289 * Reevaluate the following cap on the number of vnodes after the physical 290 * memory size exceeds 512GB. In the limit, as the physical memory size 291 * grows, the ratio of physical pages to vnodes approaches sixteen to one. 292 */ 293 #ifndef MAXVNODES_MAX 294 #define MAXVNODES_MAX (512 * (1024 * 1024 * 1024 / (int)PAGE_SIZE / 16)) 295 #endif 296 static void 297 vntblinit(void *dummy __unused) 298 { 299 int physvnodes, virtvnodes; 300 301 /* 302 * Desiredvnodes is a function of the physical memory size and the 303 * kernel's heap size. Generally speaking, it scales with the 304 * physical memory size. The ratio of desiredvnodes to physical pages 305 * is one to four until desiredvnodes exceeds 98,304. Thereafter, the 306 * marginal ratio of desiredvnodes to physical pages is one to 307 * sixteen. However, desiredvnodes is limited by the kernel's heap 308 * size. The memory required by desiredvnodes vnodes and vm objects 309 * may not exceed one seventh of the kernel's heap size. 310 */ 311 physvnodes = maxproc + cnt.v_page_count / 16 + 3 * min(98304 * 4, 312 cnt.v_page_count) / 16; 313 virtvnodes = vm_kmem_size / (7 * (sizeof(struct vm_object) + 314 sizeof(struct vnode))); 315 desiredvnodes = min(physvnodes, virtvnodes); 316 if (desiredvnodes > MAXVNODES_MAX) { 317 if (bootverbose) 318 printf("Reducing kern.maxvnodes %d -> %d\n", 319 desiredvnodes, MAXVNODES_MAX); 320 desiredvnodes = MAXVNODES_MAX; 321 } 322 wantfreevnodes = desiredvnodes / 4; 323 mtx_init(&mntid_mtx, "mntid", NULL, MTX_DEF); 324 TAILQ_INIT(&vnode_free_list); 325 mtx_init(&vnode_free_list_mtx, "vnode_free_list", NULL, MTX_DEF); 326 vnode_zone = uma_zcreate("VNODE", sizeof (struct vnode), NULL, NULL, 327 NULL, NULL, UMA_ALIGN_PTR, 0); 328 vnodepoll_zone = uma_zcreate("VNODEPOLL", sizeof (struct vpollinfo), 329 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); 330 /* 331 * Initialize the filesystem syncer. 332 */ 333 syncer_workitem_pending[WI_MPSAFEQ] = hashinit(syncer_maxdelay, M_VNODE, 334 &syncer_mask); 335 syncer_workitem_pending[WI_GIANTQ] = hashinit(syncer_maxdelay, M_VNODE, 336 &syncer_mask); 337 syncer_maxdelay = syncer_mask + 1; 338 mtx_init(&sync_mtx, "Syncer mtx", NULL, MTX_DEF); 339 cv_init(&sync_wakeup, "syncer"); 340 } 341 SYSINIT(vfs, SI_SUB_VFS, SI_ORDER_FIRST, vntblinit, NULL); 342 343 344 /* 345 * Mark a mount point as busy. Used to synchronize access and to delay 346 * unmounting. Eventually, mountlist_mtx is not released on failure. 347 * 348 * vfs_busy() is a custom lock, it can block the caller. 349 * vfs_busy() only sleeps if the unmount is active on the mount point. 350 * For a mountpoint mp, vfs_busy-enforced lock is before lock of any 351 * vnode belonging to mp. 352 * 353 * Lookup uses vfs_busy() to traverse mount points. 354 * root fs var fs 355 * / vnode lock A / vnode lock (/var) D 356 * /var vnode lock B /log vnode lock(/var/log) E 357 * vfs_busy lock C vfs_busy lock F 358 * 359 * Within each file system, the lock order is C->A->B and F->D->E. 360 * 361 * When traversing across mounts, the system follows that lock order: 362 * 363 * C->A->B 364 * | 365 * +->F->D->E 366 * 367 * The lookup() process for namei("/var") illustrates the process: 368 * VOP_LOOKUP() obtains B while A is held 369 * vfs_busy() obtains a shared lock on F while A and B are held 370 * vput() releases lock on B 371 * vput() releases lock on A 372 * VFS_ROOT() obtains lock on D while shared lock on F is held 373 * vfs_unbusy() releases shared lock on F 374 * vn_lock() obtains lock on deadfs vnode vp_crossmp instead of A. 375 * Attempt to lock A (instead of vp_crossmp) while D is held would 376 * violate the global order, causing deadlocks. 377 * 378 * dounmount() locks B while F is drained. 379 */ 380 int 381 vfs_busy(struct mount *mp, int flags) 382 { 383 384 MPASS((flags & ~MBF_MASK) == 0); 385 CTR3(KTR_VFS, "%s: mp %p with flags %d", __func__, mp, flags); 386 387 MNT_ILOCK(mp); 388 MNT_REF(mp); 389 /* 390 * If mount point is currenly being unmounted, sleep until the 391 * mount point fate is decided. If thread doing the unmounting fails, 392 * it will clear MNTK_UNMOUNT flag before waking us up, indicating 393 * that this mount point has survived the unmount attempt and vfs_busy 394 * should retry. Otherwise the unmounter thread will set MNTK_REFEXPIRE 395 * flag in addition to MNTK_UNMOUNT, indicating that mount point is 396 * about to be really destroyed. vfs_busy needs to release its 397 * reference on the mount point in this case and return with ENOENT, 398 * telling the caller that mount mount it tried to busy is no longer 399 * valid. 400 */ 401 while (mp->mnt_kern_flag & MNTK_UNMOUNT) { 402 if (flags & MBF_NOWAIT || mp->mnt_kern_flag & MNTK_REFEXPIRE) { 403 MNT_REL(mp); 404 MNT_IUNLOCK(mp); 405 CTR1(KTR_VFS, "%s: failed busying before sleeping", 406 __func__); 407 return (ENOENT); 408 } 409 if (flags & MBF_MNTLSTLOCK) 410 mtx_unlock(&mountlist_mtx); 411 mp->mnt_kern_flag |= MNTK_MWAIT; 412 msleep(mp, MNT_MTX(mp), PVFS | PDROP, "vfs_busy", 0); 413 if (flags & MBF_MNTLSTLOCK) 414 mtx_lock(&mountlist_mtx); 415 MNT_ILOCK(mp); 416 } 417 if (flags & MBF_MNTLSTLOCK) 418 mtx_unlock(&mountlist_mtx); 419 mp->mnt_lockref++; 420 MNT_IUNLOCK(mp); 421 return (0); 422 } 423 424 /* 425 * Free a busy filesystem. 426 */ 427 void 428 vfs_unbusy(struct mount *mp) 429 { 430 431 CTR2(KTR_VFS, "%s: mp %p", __func__, mp); 432 MNT_ILOCK(mp); 433 MNT_REL(mp); 434 KASSERT(mp->mnt_lockref > 0, ("negative mnt_lockref")); 435 mp->mnt_lockref--; 436 if (mp->mnt_lockref == 0 && (mp->mnt_kern_flag & MNTK_DRAINING) != 0) { 437 MPASS(mp->mnt_kern_flag & MNTK_UNMOUNT); 438 CTR1(KTR_VFS, "%s: waking up waiters", __func__); 439 mp->mnt_kern_flag &= ~MNTK_DRAINING; 440 wakeup(&mp->mnt_lockref); 441 } 442 MNT_IUNLOCK(mp); 443 } 444 445 /* 446 * Lookup a mount point by filesystem identifier. 447 */ 448 struct mount * 449 vfs_getvfs(fsid_t *fsid) 450 { 451 struct mount *mp; 452 453 CTR2(KTR_VFS, "%s: fsid %p", __func__, fsid); 454 mtx_lock(&mountlist_mtx); 455 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 456 if (mp->mnt_stat.f_fsid.val[0] == fsid->val[0] && 457 mp->mnt_stat.f_fsid.val[1] == fsid->val[1]) { 458 vfs_ref(mp); 459 mtx_unlock(&mountlist_mtx); 460 return (mp); 461 } 462 } 463 mtx_unlock(&mountlist_mtx); 464 CTR2(KTR_VFS, "%s: lookup failed for %p id", __func__, fsid); 465 return ((struct mount *) 0); 466 } 467 468 /* 469 * Lookup a mount point by filesystem identifier, busying it before 470 * returning. 471 */ 472 struct mount * 473 vfs_busyfs(fsid_t *fsid) 474 { 475 struct mount *mp; 476 int error; 477 478 CTR2(KTR_VFS, "%s: fsid %p", __func__, fsid); 479 mtx_lock(&mountlist_mtx); 480 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 481 if (mp->mnt_stat.f_fsid.val[0] == fsid->val[0] && 482 mp->mnt_stat.f_fsid.val[1] == fsid->val[1]) { 483 error = vfs_busy(mp, MBF_MNTLSTLOCK); 484 if (error) { 485 mtx_unlock(&mountlist_mtx); 486 return (NULL); 487 } 488 return (mp); 489 } 490 } 491 CTR2(KTR_VFS, "%s: lookup failed for %p id", __func__, fsid); 492 mtx_unlock(&mountlist_mtx); 493 return ((struct mount *) 0); 494 } 495 496 /* 497 * Check if a user can access privileged mount options. 498 */ 499 int 500 vfs_suser(struct mount *mp, struct thread *td) 501 { 502 int error; 503 504 /* 505 * If the thread is jailed, but this is not a jail-friendly file 506 * system, deny immediately. 507 */ 508 if (!(mp->mnt_vfc->vfc_flags & VFCF_JAIL) && jailed(td->td_ucred)) 509 return (EPERM); 510 511 /* 512 * If the file system was mounted outside the jail of the calling 513 * thread, deny immediately. 514 */ 515 if (prison_check(td->td_ucred, mp->mnt_cred) != 0) 516 return (EPERM); 517 518 /* 519 * If file system supports delegated administration, we don't check 520 * for the PRIV_VFS_MOUNT_OWNER privilege - it will be better verified 521 * by the file system itself. 522 * If this is not the user that did original mount, we check for 523 * the PRIV_VFS_MOUNT_OWNER privilege. 524 */ 525 if (!(mp->mnt_vfc->vfc_flags & VFCF_DELEGADMIN) && 526 mp->mnt_cred->cr_uid != td->td_ucred->cr_uid) { 527 if ((error = priv_check(td, PRIV_VFS_MOUNT_OWNER)) != 0) 528 return (error); 529 } 530 return (0); 531 } 532 533 /* 534 * Get a new unique fsid. Try to make its val[0] unique, since this value 535 * will be used to create fake device numbers for stat(). Also try (but 536 * not so hard) make its val[0] unique mod 2^16, since some emulators only 537 * support 16-bit device numbers. We end up with unique val[0]'s for the 538 * first 2^16 calls and unique val[0]'s mod 2^16 for the first 2^8 calls. 539 * 540 * Keep in mind that several mounts may be running in parallel. Starting 541 * the search one past where the previous search terminated is both a 542 * micro-optimization and a defense against returning the same fsid to 543 * different mounts. 544 */ 545 void 546 vfs_getnewfsid(struct mount *mp) 547 { 548 static uint16_t mntid_base; 549 struct mount *nmp; 550 fsid_t tfsid; 551 int mtype; 552 553 CTR2(KTR_VFS, "%s: mp %p", __func__, mp); 554 mtx_lock(&mntid_mtx); 555 mtype = mp->mnt_vfc->vfc_typenum; 556 tfsid.val[1] = mtype; 557 mtype = (mtype & 0xFF) << 24; 558 for (;;) { 559 tfsid.val[0] = makedev(255, 560 mtype | ((mntid_base & 0xFF00) << 8) | (mntid_base & 0xFF)); 561 mntid_base++; 562 if ((nmp = vfs_getvfs(&tfsid)) == NULL) 563 break; 564 vfs_rel(nmp); 565 } 566 mp->mnt_stat.f_fsid.val[0] = tfsid.val[0]; 567 mp->mnt_stat.f_fsid.val[1] = tfsid.val[1]; 568 mtx_unlock(&mntid_mtx); 569 } 570 571 /* 572 * Knob to control the precision of file timestamps: 573 * 574 * 0 = seconds only; nanoseconds zeroed. 575 * 1 = seconds and nanoseconds, accurate within 1/HZ. 576 * 2 = seconds and nanoseconds, truncated to microseconds. 577 * >=3 = seconds and nanoseconds, maximum precision. 578 */ 579 enum { TSP_SEC, TSP_HZ, TSP_USEC, TSP_NSEC }; 580 581 static int timestamp_precision = TSP_SEC; 582 SYSCTL_INT(_vfs, OID_AUTO, timestamp_precision, CTLFLAG_RW, 583 ×tamp_precision, 0, "File timestamp precision (0: seconds, " 584 "1: sec + ns accurate to 1/HZ, 2: sec + ns truncated to ms, " 585 "3+: sec + ns (max. precision))"); 586 587 /* 588 * Get a current timestamp. 589 */ 590 void 591 vfs_timestamp(struct timespec *tsp) 592 { 593 struct timeval tv; 594 595 switch (timestamp_precision) { 596 case TSP_SEC: 597 tsp->tv_sec = time_second; 598 tsp->tv_nsec = 0; 599 break; 600 case TSP_HZ: 601 getnanotime(tsp); 602 break; 603 case TSP_USEC: 604 microtime(&tv); 605 TIMEVAL_TO_TIMESPEC(&tv, tsp); 606 break; 607 case TSP_NSEC: 608 default: 609 nanotime(tsp); 610 break; 611 } 612 } 613 614 /* 615 * Set vnode attributes to VNOVAL 616 */ 617 void 618 vattr_null(struct vattr *vap) 619 { 620 621 vap->va_type = VNON; 622 vap->va_size = VNOVAL; 623 vap->va_bytes = VNOVAL; 624 vap->va_mode = VNOVAL; 625 vap->va_nlink = VNOVAL; 626 vap->va_uid = VNOVAL; 627 vap->va_gid = VNOVAL; 628 vap->va_fsid = VNOVAL; 629 vap->va_fileid = VNOVAL; 630 vap->va_blocksize = VNOVAL; 631 vap->va_rdev = VNOVAL; 632 vap->va_atime.tv_sec = VNOVAL; 633 vap->va_atime.tv_nsec = VNOVAL; 634 vap->va_mtime.tv_sec = VNOVAL; 635 vap->va_mtime.tv_nsec = VNOVAL; 636 vap->va_ctime.tv_sec = VNOVAL; 637 vap->va_ctime.tv_nsec = VNOVAL; 638 vap->va_birthtime.tv_sec = VNOVAL; 639 vap->va_birthtime.tv_nsec = VNOVAL; 640 vap->va_flags = VNOVAL; 641 vap->va_gen = VNOVAL; 642 vap->va_vaflags = 0; 643 } 644 645 /* 646 * This routine is called when we have too many vnodes. It attempts 647 * to free <count> vnodes and will potentially free vnodes that still 648 * have VM backing store (VM backing store is typically the cause 649 * of a vnode blowout so we want to do this). Therefore, this operation 650 * is not considered cheap. 651 * 652 * A number of conditions may prevent a vnode from being reclaimed. 653 * the buffer cache may have references on the vnode, a directory 654 * vnode may still have references due to the namei cache representing 655 * underlying files, or the vnode may be in active use. It is not 656 * desireable to reuse such vnodes. These conditions may cause the 657 * number of vnodes to reach some minimum value regardless of what 658 * you set kern.maxvnodes to. Do not set kern.maxvnodes too low. 659 */ 660 static int 661 vlrureclaim(struct mount *mp) 662 { 663 struct vnode *vp; 664 int done; 665 int trigger; 666 int usevnodes; 667 int count; 668 669 /* 670 * Calculate the trigger point, don't allow user 671 * screwups to blow us up. This prevents us from 672 * recycling vnodes with lots of resident pages. We 673 * aren't trying to free memory, we are trying to 674 * free vnodes. 675 */ 676 usevnodes = desiredvnodes; 677 if (usevnodes <= 0) 678 usevnodes = 1; 679 trigger = cnt.v_page_count * 2 / usevnodes; 680 done = 0; 681 vn_start_write(NULL, &mp, V_WAIT); 682 MNT_ILOCK(mp); 683 count = mp->mnt_nvnodelistsize / 10 + 1; 684 while (count != 0) { 685 vp = TAILQ_FIRST(&mp->mnt_nvnodelist); 686 while (vp != NULL && vp->v_type == VMARKER) 687 vp = TAILQ_NEXT(vp, v_nmntvnodes); 688 if (vp == NULL) 689 break; 690 TAILQ_REMOVE(&mp->mnt_nvnodelist, vp, v_nmntvnodes); 691 TAILQ_INSERT_TAIL(&mp->mnt_nvnodelist, vp, v_nmntvnodes); 692 --count; 693 if (!VI_TRYLOCK(vp)) 694 goto next_iter; 695 /* 696 * If it's been deconstructed already, it's still 697 * referenced, or it exceeds the trigger, skip it. 698 */ 699 if (vp->v_usecount || 700 (!vlru_allow_cache_src && 701 !LIST_EMPTY(&(vp)->v_cache_src)) || 702 (vp->v_iflag & VI_DOOMED) != 0 || (vp->v_object != NULL && 703 vp->v_object->resident_page_count > trigger)) { 704 VI_UNLOCK(vp); 705 goto next_iter; 706 } 707 MNT_IUNLOCK(mp); 708 vholdl(vp); 709 if (VOP_LOCK(vp, LK_INTERLOCK|LK_EXCLUSIVE|LK_NOWAIT)) { 710 vdrop(vp); 711 goto next_iter_mntunlocked; 712 } 713 VI_LOCK(vp); 714 /* 715 * v_usecount may have been bumped after VOP_LOCK() dropped 716 * the vnode interlock and before it was locked again. 717 * 718 * It is not necessary to recheck VI_DOOMED because it can 719 * only be set by another thread that holds both the vnode 720 * lock and vnode interlock. If another thread has the 721 * vnode lock before we get to VOP_LOCK() and obtains the 722 * vnode interlock after VOP_LOCK() drops the vnode 723 * interlock, the other thread will be unable to drop the 724 * vnode lock before our VOP_LOCK() call fails. 725 */ 726 if (vp->v_usecount || 727 (!vlru_allow_cache_src && 728 !LIST_EMPTY(&(vp)->v_cache_src)) || 729 (vp->v_object != NULL && 730 vp->v_object->resident_page_count > trigger)) { 731 VOP_UNLOCK(vp, LK_INTERLOCK); 732 goto next_iter_mntunlocked; 733 } 734 KASSERT((vp->v_iflag & VI_DOOMED) == 0, 735 ("VI_DOOMED unexpectedly detected in vlrureclaim()")); 736 vgonel(vp); 737 VOP_UNLOCK(vp, 0); 738 vdropl(vp); 739 done++; 740 next_iter_mntunlocked: 741 if (!should_yield()) 742 goto relock_mnt; 743 goto yield; 744 next_iter: 745 if (!should_yield()) 746 continue; 747 MNT_IUNLOCK(mp); 748 yield: 749 kern_yield(PRI_UNCHANGED); 750 relock_mnt: 751 MNT_ILOCK(mp); 752 } 753 MNT_IUNLOCK(mp); 754 vn_finished_write(mp); 755 return done; 756 } 757 758 /* 759 * Attempt to keep the free list at wantfreevnodes length. 760 */ 761 static void 762 vnlru_free(int count) 763 { 764 struct vnode *vp; 765 int vfslocked; 766 767 mtx_assert(&vnode_free_list_mtx, MA_OWNED); 768 for (; count > 0; count--) { 769 vp = TAILQ_FIRST(&vnode_free_list); 770 /* 771 * The list can be modified while the free_list_mtx 772 * has been dropped and vp could be NULL here. 773 */ 774 if (!vp) 775 break; 776 VNASSERT(vp->v_op != NULL, vp, 777 ("vnlru_free: vnode already reclaimed.")); 778 KASSERT((vp->v_iflag & VI_FREE) != 0, 779 ("Removing vnode not on freelist")); 780 KASSERT((vp->v_iflag & VI_ACTIVE) == 0, 781 ("Mangling active vnode")); 782 TAILQ_REMOVE(&vnode_free_list, vp, v_actfreelist); 783 /* 784 * Don't recycle if we can't get the interlock. 785 */ 786 if (!VI_TRYLOCK(vp)) { 787 TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_actfreelist); 788 continue; 789 } 790 VNASSERT(VCANRECYCLE(vp), vp, 791 ("vp inconsistent on freelist")); 792 freevnodes--; 793 vp->v_iflag &= ~VI_FREE; 794 vholdl(vp); 795 mtx_unlock(&vnode_free_list_mtx); 796 VI_UNLOCK(vp); 797 vfslocked = VFS_LOCK_GIANT(vp->v_mount); 798 vtryrecycle(vp); 799 VFS_UNLOCK_GIANT(vfslocked); 800 /* 801 * If the recycled succeeded this vdrop will actually free 802 * the vnode. If not it will simply place it back on 803 * the free list. 804 */ 805 vdrop(vp); 806 mtx_lock(&vnode_free_list_mtx); 807 } 808 } 809 /* 810 * Attempt to recycle vnodes in a context that is always safe to block. 811 * Calling vlrurecycle() from the bowels of filesystem code has some 812 * interesting deadlock problems. 813 */ 814 static struct proc *vnlruproc; 815 static int vnlruproc_sig; 816 817 static void 818 vnlru_proc(void) 819 { 820 struct mount *mp, *nmp; 821 int done, vfslocked; 822 struct proc *p = vnlruproc; 823 824 EVENTHANDLER_REGISTER(shutdown_pre_sync, kproc_shutdown, p, 825 SHUTDOWN_PRI_FIRST); 826 827 for (;;) { 828 kproc_suspend_check(p); 829 mtx_lock(&vnode_free_list_mtx); 830 if (freevnodes > wantfreevnodes) 831 vnlru_free(freevnodes - wantfreevnodes); 832 if (numvnodes <= desiredvnodes * 9 / 10) { 833 vnlruproc_sig = 0; 834 wakeup(&vnlruproc_sig); 835 msleep(vnlruproc, &vnode_free_list_mtx, 836 PVFS|PDROP, "vlruwt", hz); 837 continue; 838 } 839 mtx_unlock(&vnode_free_list_mtx); 840 done = 0; 841 mtx_lock(&mountlist_mtx); 842 for (mp = TAILQ_FIRST(&mountlist); mp != NULL; mp = nmp) { 843 if (vfs_busy(mp, MBF_NOWAIT | MBF_MNTLSTLOCK)) { 844 nmp = TAILQ_NEXT(mp, mnt_list); 845 continue; 846 } 847 vfslocked = VFS_LOCK_GIANT(mp); 848 done += vlrureclaim(mp); 849 VFS_UNLOCK_GIANT(vfslocked); 850 mtx_lock(&mountlist_mtx); 851 nmp = TAILQ_NEXT(mp, mnt_list); 852 vfs_unbusy(mp); 853 } 854 mtx_unlock(&mountlist_mtx); 855 if (done == 0) { 856 #if 0 857 /* These messages are temporary debugging aids */ 858 if (vnlru_nowhere < 5) 859 printf("vnlru process getting nowhere..\n"); 860 else if (vnlru_nowhere == 5) 861 printf("vnlru process messages stopped.\n"); 862 #endif 863 vnlru_nowhere++; 864 tsleep(vnlruproc, PPAUSE, "vlrup", hz * 3); 865 } else 866 kern_yield(PRI_UNCHANGED); 867 } 868 } 869 870 static struct kproc_desc vnlru_kp = { 871 "vnlru", 872 vnlru_proc, 873 &vnlruproc 874 }; 875 SYSINIT(vnlru, SI_SUB_KTHREAD_UPDATE, SI_ORDER_FIRST, kproc_start, 876 &vnlru_kp); 877 878 /* 879 * Routines having to do with the management of the vnode table. 880 */ 881 882 /* 883 * Try to recycle a freed vnode. We abort if anyone picks up a reference 884 * before we actually vgone(). This function must be called with the vnode 885 * held to prevent the vnode from being returned to the free list midway 886 * through vgone(). 887 */ 888 static int 889 vtryrecycle(struct vnode *vp) 890 { 891 struct mount *vnmp; 892 893 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 894 VNASSERT(vp->v_holdcnt, vp, 895 ("vtryrecycle: Recycling vp %p without a reference.", vp)); 896 /* 897 * This vnode may found and locked via some other list, if so we 898 * can't recycle it yet. 899 */ 900 if (VOP_LOCK(vp, LK_EXCLUSIVE | LK_NOWAIT) != 0) { 901 CTR2(KTR_VFS, 902 "%s: impossible to recycle, vp %p lock is already held", 903 __func__, vp); 904 return (EWOULDBLOCK); 905 } 906 /* 907 * Don't recycle if its filesystem is being suspended. 908 */ 909 if (vn_start_write(vp, &vnmp, V_NOWAIT) != 0) { 910 VOP_UNLOCK(vp, 0); 911 CTR2(KTR_VFS, 912 "%s: impossible to recycle, cannot start the write for %p", 913 __func__, vp); 914 return (EBUSY); 915 } 916 /* 917 * If we got this far, we need to acquire the interlock and see if 918 * anyone picked up this vnode from another list. If not, we will 919 * mark it with DOOMED via vgonel() so that anyone who does find it 920 * will skip over it. 921 */ 922 VI_LOCK(vp); 923 if (vp->v_usecount) { 924 VOP_UNLOCK(vp, LK_INTERLOCK); 925 vn_finished_write(vnmp); 926 CTR2(KTR_VFS, 927 "%s: impossible to recycle, %p is already referenced", 928 __func__, vp); 929 return (EBUSY); 930 } 931 if ((vp->v_iflag & VI_DOOMED) == 0) 932 vgonel(vp); 933 VOP_UNLOCK(vp, LK_INTERLOCK); 934 vn_finished_write(vnmp); 935 return (0); 936 } 937 938 /* 939 * Return the next vnode from the free list. 940 */ 941 int 942 getnewvnode(const char *tag, struct mount *mp, struct vop_vector *vops, 943 struct vnode **vpp) 944 { 945 struct vnode *vp = NULL; 946 struct bufobj *bo; 947 948 CTR3(KTR_VFS, "%s: mp %p with tag %s", __func__, mp, tag); 949 mtx_lock(&vnode_free_list_mtx); 950 /* 951 * Lend our context to reclaim vnodes if they've exceeded the max. 952 */ 953 if (freevnodes > wantfreevnodes) 954 vnlru_free(1); 955 /* 956 * Wait for available vnodes. 957 */ 958 if (numvnodes > desiredvnodes) { 959 if (mp != NULL && (mp->mnt_kern_flag & MNTK_SUSPEND)) { 960 /* 961 * File system is beeing suspended, we cannot risk a 962 * deadlock here, so allocate new vnode anyway. 963 */ 964 if (freevnodes > wantfreevnodes) 965 vnlru_free(freevnodes - wantfreevnodes); 966 goto alloc; 967 } 968 if (vnlruproc_sig == 0) { 969 vnlruproc_sig = 1; /* avoid unnecessary wakeups */ 970 wakeup(vnlruproc); 971 } 972 msleep(&vnlruproc_sig, &vnode_free_list_mtx, PVFS, 973 "vlruwk", hz); 974 #if 0 /* XXX Not all VFS_VGET/ffs_vget callers check returns. */ 975 if (numvnodes > desiredvnodes) { 976 mtx_unlock(&vnode_free_list_mtx); 977 return (ENFILE); 978 } 979 #endif 980 } 981 alloc: 982 numvnodes++; 983 mtx_unlock(&vnode_free_list_mtx); 984 vp = (struct vnode *) uma_zalloc(vnode_zone, M_WAITOK|M_ZERO); 985 /* 986 * Setup locks. 987 */ 988 vp->v_vnlock = &vp->v_lock; 989 mtx_init(&vp->v_interlock, "vnode interlock", NULL, MTX_DEF); 990 /* 991 * By default, don't allow shared locks unless filesystems 992 * opt-in. 993 */ 994 lockinit(vp->v_vnlock, PVFS, tag, VLKTIMEOUT, LK_NOSHARE); 995 /* 996 * Initialize bufobj. 997 */ 998 bo = &vp->v_bufobj; 999 bo->__bo_vnode = vp; 1000 mtx_init(BO_MTX(bo), "bufobj interlock", NULL, MTX_DEF); 1001 bo->bo_ops = &buf_ops_bio; 1002 bo->bo_private = vp; 1003 TAILQ_INIT(&bo->bo_clean.bv_hd); 1004 TAILQ_INIT(&bo->bo_dirty.bv_hd); 1005 /* 1006 * Initialize namecache. 1007 */ 1008 LIST_INIT(&vp->v_cache_src); 1009 TAILQ_INIT(&vp->v_cache_dst); 1010 /* 1011 * Finalize various vnode identity bits. 1012 */ 1013 vp->v_type = VNON; 1014 vp->v_tag = tag; 1015 vp->v_op = vops; 1016 v_incr_usecount(vp); 1017 vp->v_data = NULL; 1018 #ifdef MAC 1019 mac_vnode_init(vp); 1020 if (mp != NULL && (mp->mnt_flag & MNT_MULTILABEL) == 0) 1021 mac_vnode_associate_singlelabel(mp, vp); 1022 else if (mp == NULL && vops != &dead_vnodeops) 1023 printf("NULL mp in getnewvnode()\n"); 1024 #endif 1025 if (mp != NULL) { 1026 bo->bo_bsize = mp->mnt_stat.f_iosize; 1027 if ((mp->mnt_kern_flag & MNTK_NOKNOTE) != 0) 1028 vp->v_vflag |= VV_NOKNOTE; 1029 } 1030 rangelock_init(&vp->v_rl); 1031 1032 *vpp = vp; 1033 return (0); 1034 } 1035 1036 /* 1037 * Delete from old mount point vnode list, if on one. 1038 */ 1039 static void 1040 delmntque(struct vnode *vp) 1041 { 1042 struct mount *mp; 1043 int active; 1044 1045 mp = vp->v_mount; 1046 if (mp == NULL) 1047 return; 1048 MNT_ILOCK(mp); 1049 VI_LOCK(vp); 1050 KASSERT(mp->mnt_activevnodelistsize <= mp->mnt_nvnodelistsize, 1051 ("Active vnode list size %d > Vnode list size %d", 1052 mp->mnt_activevnodelistsize, mp->mnt_nvnodelistsize)); 1053 active = vp->v_iflag & VI_ACTIVE; 1054 vp->v_iflag &= ~VI_ACTIVE; 1055 if (active) { 1056 mtx_lock(&vnode_free_list_mtx); 1057 TAILQ_REMOVE(&mp->mnt_activevnodelist, vp, v_actfreelist); 1058 mp->mnt_activevnodelistsize--; 1059 mtx_unlock(&vnode_free_list_mtx); 1060 } 1061 vp->v_mount = NULL; 1062 VI_UNLOCK(vp); 1063 VNASSERT(mp->mnt_nvnodelistsize > 0, vp, 1064 ("bad mount point vnode list size")); 1065 TAILQ_REMOVE(&mp->mnt_nvnodelist, vp, v_nmntvnodes); 1066 mp->mnt_nvnodelistsize--; 1067 MNT_REL(mp); 1068 MNT_IUNLOCK(mp); 1069 } 1070 1071 static void 1072 insmntque_stddtr(struct vnode *vp, void *dtr_arg) 1073 { 1074 1075 vp->v_data = NULL; 1076 vp->v_op = &dead_vnodeops; 1077 /* XXX non mp-safe fs may still call insmntque with vnode 1078 unlocked */ 1079 if (!VOP_ISLOCKED(vp)) 1080 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 1081 vgone(vp); 1082 vput(vp); 1083 } 1084 1085 /* 1086 * Insert into list of vnodes for the new mount point, if available. 1087 */ 1088 int 1089 insmntque1(struct vnode *vp, struct mount *mp, 1090 void (*dtr)(struct vnode *, void *), void *dtr_arg) 1091 { 1092 int locked; 1093 1094 KASSERT(vp->v_mount == NULL, 1095 ("insmntque: vnode already on per mount vnode list")); 1096 VNASSERT(mp != NULL, vp, ("Don't call insmntque(foo, NULL)")); 1097 #ifdef DEBUG_VFS_LOCKS 1098 if (!VFS_NEEDSGIANT(mp)) 1099 ASSERT_VOP_ELOCKED(vp, 1100 "insmntque: mp-safe fs and non-locked vp"); 1101 #endif 1102 /* 1103 * We acquire the vnode interlock early to ensure that the 1104 * vnode cannot be recycled by another process releasing a 1105 * holdcnt on it before we get it on both the vnode list 1106 * and the active vnode list. The mount mutex protects only 1107 * manipulation of the vnode list and the vnode freelist 1108 * mutex protects only manipulation of the active vnode list. 1109 * Hence the need to hold the vnode interlock throughout. 1110 */ 1111 MNT_ILOCK(mp); 1112 VI_LOCK(vp); 1113 if ((mp->mnt_kern_flag & MNTK_NOINSMNTQ) != 0 && 1114 ((mp->mnt_kern_flag & MNTK_UNMOUNTF) != 0 || 1115 mp->mnt_nvnodelistsize == 0)) { 1116 locked = VOP_ISLOCKED(vp); 1117 if (!locked || (locked == LK_EXCLUSIVE && 1118 (vp->v_vflag & VV_FORCEINSMQ) == 0)) { 1119 VI_UNLOCK(vp); 1120 MNT_IUNLOCK(mp); 1121 if (dtr != NULL) 1122 dtr(vp, dtr_arg); 1123 return (EBUSY); 1124 } 1125 } 1126 vp->v_mount = mp; 1127 MNT_REF(mp); 1128 TAILQ_INSERT_TAIL(&mp->mnt_nvnodelist, vp, v_nmntvnodes); 1129 VNASSERT(mp->mnt_nvnodelistsize >= 0, vp, 1130 ("neg mount point vnode list size")); 1131 mp->mnt_nvnodelistsize++; 1132 KASSERT((vp->v_iflag & VI_ACTIVE) == 0, 1133 ("Activating already active vnode")); 1134 vp->v_iflag |= VI_ACTIVE; 1135 mtx_lock(&vnode_free_list_mtx); 1136 TAILQ_INSERT_HEAD(&mp->mnt_activevnodelist, vp, v_actfreelist); 1137 mp->mnt_activevnodelistsize++; 1138 mtx_unlock(&vnode_free_list_mtx); 1139 VI_UNLOCK(vp); 1140 MNT_IUNLOCK(mp); 1141 return (0); 1142 } 1143 1144 int 1145 insmntque(struct vnode *vp, struct mount *mp) 1146 { 1147 1148 return (insmntque1(vp, mp, insmntque_stddtr, NULL)); 1149 } 1150 1151 /* 1152 * Flush out and invalidate all buffers associated with a bufobj 1153 * Called with the underlying object locked. 1154 */ 1155 int 1156 bufobj_invalbuf(struct bufobj *bo, int flags, int slpflag, int slptimeo) 1157 { 1158 int error; 1159 1160 BO_LOCK(bo); 1161 if (flags & V_SAVE) { 1162 error = bufobj_wwait(bo, slpflag, slptimeo); 1163 if (error) { 1164 BO_UNLOCK(bo); 1165 return (error); 1166 } 1167 if (bo->bo_dirty.bv_cnt > 0) { 1168 BO_UNLOCK(bo); 1169 if ((error = BO_SYNC(bo, MNT_WAIT)) != 0) 1170 return (error); 1171 /* 1172 * XXX We could save a lock/unlock if this was only 1173 * enabled under INVARIANTS 1174 */ 1175 BO_LOCK(bo); 1176 if (bo->bo_numoutput > 0 || bo->bo_dirty.bv_cnt > 0) 1177 panic("vinvalbuf: dirty bufs"); 1178 } 1179 } 1180 /* 1181 * If you alter this loop please notice that interlock is dropped and 1182 * reacquired in flushbuflist. Special care is needed to ensure that 1183 * no race conditions occur from this. 1184 */ 1185 do { 1186 error = flushbuflist(&bo->bo_clean, 1187 flags, bo, slpflag, slptimeo); 1188 if (error == 0 && !(flags & V_CLEANONLY)) 1189 error = flushbuflist(&bo->bo_dirty, 1190 flags, bo, slpflag, slptimeo); 1191 if (error != 0 && error != EAGAIN) { 1192 BO_UNLOCK(bo); 1193 return (error); 1194 } 1195 } while (error != 0); 1196 1197 /* 1198 * Wait for I/O to complete. XXX needs cleaning up. The vnode can 1199 * have write I/O in-progress but if there is a VM object then the 1200 * VM object can also have read-I/O in-progress. 1201 */ 1202 do { 1203 bufobj_wwait(bo, 0, 0); 1204 BO_UNLOCK(bo); 1205 if (bo->bo_object != NULL) { 1206 VM_OBJECT_LOCK(bo->bo_object); 1207 vm_object_pip_wait(bo->bo_object, "bovlbx"); 1208 VM_OBJECT_UNLOCK(bo->bo_object); 1209 } 1210 BO_LOCK(bo); 1211 } while (bo->bo_numoutput > 0); 1212 BO_UNLOCK(bo); 1213 1214 /* 1215 * Destroy the copy in the VM cache, too. 1216 */ 1217 if (bo->bo_object != NULL && 1218 (flags & (V_ALT | V_NORMAL | V_CLEANONLY)) == 0) { 1219 VM_OBJECT_LOCK(bo->bo_object); 1220 vm_object_page_remove(bo->bo_object, 0, 0, (flags & V_SAVE) ? 1221 OBJPR_CLEANONLY : 0); 1222 VM_OBJECT_UNLOCK(bo->bo_object); 1223 } 1224 1225 #ifdef INVARIANTS 1226 BO_LOCK(bo); 1227 if ((flags & (V_ALT | V_NORMAL | V_CLEANONLY)) == 0 && 1228 (bo->bo_dirty.bv_cnt > 0 || bo->bo_clean.bv_cnt > 0)) 1229 panic("vinvalbuf: flush failed"); 1230 BO_UNLOCK(bo); 1231 #endif 1232 return (0); 1233 } 1234 1235 /* 1236 * Flush out and invalidate all buffers associated with a vnode. 1237 * Called with the underlying object locked. 1238 */ 1239 int 1240 vinvalbuf(struct vnode *vp, int flags, int slpflag, int slptimeo) 1241 { 1242 1243 CTR3(KTR_VFS, "%s: vp %p with flags %d", __func__, vp, flags); 1244 ASSERT_VOP_LOCKED(vp, "vinvalbuf"); 1245 return (bufobj_invalbuf(&vp->v_bufobj, flags, slpflag, slptimeo)); 1246 } 1247 1248 /* 1249 * Flush out buffers on the specified list. 1250 * 1251 */ 1252 static int 1253 flushbuflist(struct bufv *bufv, int flags, struct bufobj *bo, int slpflag, 1254 int slptimeo) 1255 { 1256 struct buf *bp, *nbp; 1257 int retval, error; 1258 daddr_t lblkno; 1259 b_xflags_t xflags; 1260 1261 ASSERT_BO_LOCKED(bo); 1262 1263 retval = 0; 1264 TAILQ_FOREACH_SAFE(bp, &bufv->bv_hd, b_bobufs, nbp) { 1265 if (((flags & V_NORMAL) && (bp->b_xflags & BX_ALTDATA)) || 1266 ((flags & V_ALT) && (bp->b_xflags & BX_ALTDATA) == 0)) { 1267 continue; 1268 } 1269 lblkno = 0; 1270 xflags = 0; 1271 if (nbp != NULL) { 1272 lblkno = nbp->b_lblkno; 1273 xflags = nbp->b_xflags & 1274 (BX_BKGRDMARKER | BX_VNDIRTY | BX_VNCLEAN); 1275 } 1276 retval = EAGAIN; 1277 error = BUF_TIMELOCK(bp, 1278 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, BO_MTX(bo), 1279 "flushbuf", slpflag, slptimeo); 1280 if (error) { 1281 BO_LOCK(bo); 1282 return (error != ENOLCK ? error : EAGAIN); 1283 } 1284 KASSERT(bp->b_bufobj == bo, 1285 ("bp %p wrong b_bufobj %p should be %p", 1286 bp, bp->b_bufobj, bo)); 1287 if (bp->b_bufobj != bo) { /* XXX: necessary ? */ 1288 BUF_UNLOCK(bp); 1289 BO_LOCK(bo); 1290 return (EAGAIN); 1291 } 1292 /* 1293 * XXX Since there are no node locks for NFS, I 1294 * believe there is a slight chance that a delayed 1295 * write will occur while sleeping just above, so 1296 * check for it. 1297 */ 1298 if (((bp->b_flags & (B_DELWRI | B_INVAL)) == B_DELWRI) && 1299 (flags & V_SAVE)) { 1300 BO_LOCK(bo); 1301 bremfree(bp); 1302 BO_UNLOCK(bo); 1303 bp->b_flags |= B_ASYNC; 1304 bwrite(bp); 1305 BO_LOCK(bo); 1306 return (EAGAIN); /* XXX: why not loop ? */ 1307 } 1308 BO_LOCK(bo); 1309 bremfree(bp); 1310 BO_UNLOCK(bo); 1311 bp->b_flags |= (B_INVAL | B_RELBUF); 1312 bp->b_flags &= ~B_ASYNC; 1313 brelse(bp); 1314 BO_LOCK(bo); 1315 if (nbp != NULL && 1316 (nbp->b_bufobj != bo || 1317 nbp->b_lblkno != lblkno || 1318 (nbp->b_xflags & 1319 (BX_BKGRDMARKER | BX_VNDIRTY | BX_VNCLEAN)) != xflags)) 1320 break; /* nbp invalid */ 1321 } 1322 return (retval); 1323 } 1324 1325 /* 1326 * Truncate a file's buffer and pages to a specified length. This 1327 * is in lieu of the old vinvalbuf mechanism, which performed unneeded 1328 * sync activity. 1329 */ 1330 int 1331 vtruncbuf(struct vnode *vp, struct ucred *cred, off_t length, int blksize) 1332 { 1333 struct buf *bp, *nbp; 1334 int anyfreed; 1335 int trunclbn; 1336 struct bufobj *bo; 1337 1338 CTR5(KTR_VFS, "%s: vp %p with cred %p and block %d:%ju", __func__, 1339 vp, cred, blksize, (uintmax_t)length); 1340 1341 /* 1342 * Round up to the *next* lbn. 1343 */ 1344 trunclbn = (length + blksize - 1) / blksize; 1345 1346 ASSERT_VOP_LOCKED(vp, "vtruncbuf"); 1347 restart: 1348 bo = &vp->v_bufobj; 1349 BO_LOCK(bo); 1350 anyfreed = 1; 1351 for (;anyfreed;) { 1352 anyfreed = 0; 1353 TAILQ_FOREACH_SAFE(bp, &bo->bo_clean.bv_hd, b_bobufs, nbp) { 1354 if (bp->b_lblkno < trunclbn) 1355 continue; 1356 if (BUF_LOCK(bp, 1357 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, 1358 BO_MTX(bo)) == ENOLCK) 1359 goto restart; 1360 1361 BO_LOCK(bo); 1362 bremfree(bp); 1363 BO_UNLOCK(bo); 1364 bp->b_flags |= (B_INVAL | B_RELBUF); 1365 bp->b_flags &= ~B_ASYNC; 1366 brelse(bp); 1367 anyfreed = 1; 1368 1369 BO_LOCK(bo); 1370 if (nbp != NULL && 1371 (((nbp->b_xflags & BX_VNCLEAN) == 0) || 1372 (nbp->b_vp != vp) || 1373 (nbp->b_flags & B_DELWRI))) { 1374 BO_UNLOCK(bo); 1375 goto restart; 1376 } 1377 } 1378 1379 TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) { 1380 if (bp->b_lblkno < trunclbn) 1381 continue; 1382 if (BUF_LOCK(bp, 1383 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, 1384 BO_MTX(bo)) == ENOLCK) 1385 goto restart; 1386 BO_LOCK(bo); 1387 bremfree(bp); 1388 BO_UNLOCK(bo); 1389 bp->b_flags |= (B_INVAL | B_RELBUF); 1390 bp->b_flags &= ~B_ASYNC; 1391 brelse(bp); 1392 anyfreed = 1; 1393 1394 BO_LOCK(bo); 1395 if (nbp != NULL && 1396 (((nbp->b_xflags & BX_VNDIRTY) == 0) || 1397 (nbp->b_vp != vp) || 1398 (nbp->b_flags & B_DELWRI) == 0)) { 1399 BO_UNLOCK(bo); 1400 goto restart; 1401 } 1402 } 1403 } 1404 1405 if (length > 0) { 1406 restartsync: 1407 TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) { 1408 if (bp->b_lblkno > 0) 1409 continue; 1410 /* 1411 * Since we hold the vnode lock this should only 1412 * fail if we're racing with the buf daemon. 1413 */ 1414 if (BUF_LOCK(bp, 1415 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, 1416 BO_MTX(bo)) == ENOLCK) { 1417 goto restart; 1418 } 1419 VNASSERT((bp->b_flags & B_DELWRI), vp, 1420 ("buf(%p) on dirty queue without DELWRI", bp)); 1421 1422 BO_LOCK(bo); 1423 bremfree(bp); 1424 BO_UNLOCK(bo); 1425 bawrite(bp); 1426 BO_LOCK(bo); 1427 goto restartsync; 1428 } 1429 } 1430 1431 bufobj_wwait(bo, 0, 0); 1432 BO_UNLOCK(bo); 1433 vnode_pager_setsize(vp, length); 1434 1435 return (0); 1436 } 1437 1438 /* 1439 * buf_splay() - splay tree core for the clean/dirty list of buffers in 1440 * a vnode. 1441 * 1442 * NOTE: We have to deal with the special case of a background bitmap 1443 * buffer, a situation where two buffers will have the same logical 1444 * block offset. We want (1) only the foreground buffer to be accessed 1445 * in a lookup and (2) must differentiate between the foreground and 1446 * background buffer in the splay tree algorithm because the splay 1447 * tree cannot normally handle multiple entities with the same 'index'. 1448 * We accomplish this by adding differentiating flags to the splay tree's 1449 * numerical domain. 1450 */ 1451 static 1452 struct buf * 1453 buf_splay(daddr_t lblkno, b_xflags_t xflags, struct buf *root) 1454 { 1455 struct buf dummy; 1456 struct buf *lefttreemax, *righttreemin, *y; 1457 1458 if (root == NULL) 1459 return (NULL); 1460 lefttreemax = righttreemin = &dummy; 1461 for (;;) { 1462 if (lblkno < root->b_lblkno || 1463 (lblkno == root->b_lblkno && 1464 (xflags & BX_BKGRDMARKER) < (root->b_xflags & BX_BKGRDMARKER))) { 1465 if ((y = root->b_left) == NULL) 1466 break; 1467 if (lblkno < y->b_lblkno) { 1468 /* Rotate right. */ 1469 root->b_left = y->b_right; 1470 y->b_right = root; 1471 root = y; 1472 if ((y = root->b_left) == NULL) 1473 break; 1474 } 1475 /* Link into the new root's right tree. */ 1476 righttreemin->b_left = root; 1477 righttreemin = root; 1478 } else if (lblkno > root->b_lblkno || 1479 (lblkno == root->b_lblkno && 1480 (xflags & BX_BKGRDMARKER) > (root->b_xflags & BX_BKGRDMARKER))) { 1481 if ((y = root->b_right) == NULL) 1482 break; 1483 if (lblkno > y->b_lblkno) { 1484 /* Rotate left. */ 1485 root->b_right = y->b_left; 1486 y->b_left = root; 1487 root = y; 1488 if ((y = root->b_right) == NULL) 1489 break; 1490 } 1491 /* Link into the new root's left tree. */ 1492 lefttreemax->b_right = root; 1493 lefttreemax = root; 1494 } else { 1495 break; 1496 } 1497 root = y; 1498 } 1499 /* Assemble the new root. */ 1500 lefttreemax->b_right = root->b_left; 1501 righttreemin->b_left = root->b_right; 1502 root->b_left = dummy.b_right; 1503 root->b_right = dummy.b_left; 1504 return (root); 1505 } 1506 1507 static void 1508 buf_vlist_remove(struct buf *bp) 1509 { 1510 struct buf *root; 1511 struct bufv *bv; 1512 1513 KASSERT(bp->b_bufobj != NULL, ("No b_bufobj %p", bp)); 1514 ASSERT_BO_LOCKED(bp->b_bufobj); 1515 KASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) != 1516 (BX_VNDIRTY|BX_VNCLEAN), 1517 ("buf_vlist_remove: Buf %p is on two lists", bp)); 1518 if (bp->b_xflags & BX_VNDIRTY) 1519 bv = &bp->b_bufobj->bo_dirty; 1520 else 1521 bv = &bp->b_bufobj->bo_clean; 1522 if (bp != bv->bv_root) { 1523 root = buf_splay(bp->b_lblkno, bp->b_xflags, bv->bv_root); 1524 KASSERT(root == bp, ("splay lookup failed in remove")); 1525 } 1526 if (bp->b_left == NULL) { 1527 root = bp->b_right; 1528 } else { 1529 root = buf_splay(bp->b_lblkno, bp->b_xflags, bp->b_left); 1530 root->b_right = bp->b_right; 1531 } 1532 bv->bv_root = root; 1533 TAILQ_REMOVE(&bv->bv_hd, bp, b_bobufs); 1534 bv->bv_cnt--; 1535 bp->b_xflags &= ~(BX_VNDIRTY | BX_VNCLEAN); 1536 } 1537 1538 /* 1539 * Add the buffer to the sorted clean or dirty block list using a 1540 * splay tree algorithm. 1541 * 1542 * NOTE: xflags is passed as a constant, optimizing this inline function! 1543 */ 1544 static void 1545 buf_vlist_add(struct buf *bp, struct bufobj *bo, b_xflags_t xflags) 1546 { 1547 struct buf *root; 1548 struct bufv *bv; 1549 1550 ASSERT_BO_LOCKED(bo); 1551 KASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) == 0, 1552 ("buf_vlist_add: Buf %p has existing xflags %d", bp, bp->b_xflags)); 1553 bp->b_xflags |= xflags; 1554 if (xflags & BX_VNDIRTY) 1555 bv = &bo->bo_dirty; 1556 else 1557 bv = &bo->bo_clean; 1558 1559 root = buf_splay(bp->b_lblkno, bp->b_xflags, bv->bv_root); 1560 if (root == NULL) { 1561 bp->b_left = NULL; 1562 bp->b_right = NULL; 1563 TAILQ_INSERT_TAIL(&bv->bv_hd, bp, b_bobufs); 1564 } else if (bp->b_lblkno < root->b_lblkno || 1565 (bp->b_lblkno == root->b_lblkno && 1566 (bp->b_xflags & BX_BKGRDMARKER) < (root->b_xflags & BX_BKGRDMARKER))) { 1567 bp->b_left = root->b_left; 1568 bp->b_right = root; 1569 root->b_left = NULL; 1570 TAILQ_INSERT_BEFORE(root, bp, b_bobufs); 1571 } else { 1572 bp->b_right = root->b_right; 1573 bp->b_left = root; 1574 root->b_right = NULL; 1575 TAILQ_INSERT_AFTER(&bv->bv_hd, root, bp, b_bobufs); 1576 } 1577 bv->bv_cnt++; 1578 bv->bv_root = bp; 1579 } 1580 1581 /* 1582 * Lookup a buffer using the splay tree. Note that we specifically avoid 1583 * shadow buffers used in background bitmap writes. 1584 * 1585 * This code isn't quite efficient as it could be because we are maintaining 1586 * two sorted lists and do not know which list the block resides in. 1587 * 1588 * During a "make buildworld" the desired buffer is found at one of 1589 * the roots more than 60% of the time. Thus, checking both roots 1590 * before performing either splay eliminates unnecessary splays on the 1591 * first tree splayed. 1592 */ 1593 struct buf * 1594 gbincore(struct bufobj *bo, daddr_t lblkno) 1595 { 1596 struct buf *bp; 1597 1598 ASSERT_BO_LOCKED(bo); 1599 if ((bp = bo->bo_clean.bv_root) != NULL && 1600 bp->b_lblkno == lblkno && !(bp->b_xflags & BX_BKGRDMARKER)) 1601 return (bp); 1602 if ((bp = bo->bo_dirty.bv_root) != NULL && 1603 bp->b_lblkno == lblkno && !(bp->b_xflags & BX_BKGRDMARKER)) 1604 return (bp); 1605 if ((bp = bo->bo_clean.bv_root) != NULL) { 1606 bo->bo_clean.bv_root = bp = buf_splay(lblkno, 0, bp); 1607 if (bp->b_lblkno == lblkno && !(bp->b_xflags & BX_BKGRDMARKER)) 1608 return (bp); 1609 } 1610 if ((bp = bo->bo_dirty.bv_root) != NULL) { 1611 bo->bo_dirty.bv_root = bp = buf_splay(lblkno, 0, bp); 1612 if (bp->b_lblkno == lblkno && !(bp->b_xflags & BX_BKGRDMARKER)) 1613 return (bp); 1614 } 1615 return (NULL); 1616 } 1617 1618 /* 1619 * Associate a buffer with a vnode. 1620 */ 1621 void 1622 bgetvp(struct vnode *vp, struct buf *bp) 1623 { 1624 struct bufobj *bo; 1625 1626 bo = &vp->v_bufobj; 1627 ASSERT_BO_LOCKED(bo); 1628 VNASSERT(bp->b_vp == NULL, bp->b_vp, ("bgetvp: not free")); 1629 1630 CTR3(KTR_BUF, "bgetvp(%p) vp %p flags %X", bp, vp, bp->b_flags); 1631 VNASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) == 0, vp, 1632 ("bgetvp: bp already attached! %p", bp)); 1633 1634 vhold(vp); 1635 if (VFS_NEEDSGIANT(vp->v_mount) || bo->bo_flag & BO_NEEDSGIANT) 1636 bp->b_flags |= B_NEEDSGIANT; 1637 bp->b_vp = vp; 1638 bp->b_bufobj = bo; 1639 /* 1640 * Insert onto list for new vnode. 1641 */ 1642 buf_vlist_add(bp, bo, BX_VNCLEAN); 1643 } 1644 1645 /* 1646 * Disassociate a buffer from a vnode. 1647 */ 1648 void 1649 brelvp(struct buf *bp) 1650 { 1651 struct bufobj *bo; 1652 struct vnode *vp; 1653 1654 CTR3(KTR_BUF, "brelvp(%p) vp %p flags %X", bp, bp->b_vp, bp->b_flags); 1655 KASSERT(bp->b_vp != NULL, ("brelvp: NULL")); 1656 1657 /* 1658 * Delete from old vnode list, if on one. 1659 */ 1660 vp = bp->b_vp; /* XXX */ 1661 bo = bp->b_bufobj; 1662 BO_LOCK(bo); 1663 if (bp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN)) 1664 buf_vlist_remove(bp); 1665 else 1666 panic("brelvp: Buffer %p not on queue.", bp); 1667 if ((bo->bo_flag & BO_ONWORKLST) && bo->bo_dirty.bv_cnt == 0) { 1668 bo->bo_flag &= ~BO_ONWORKLST; 1669 mtx_lock(&sync_mtx); 1670 LIST_REMOVE(bo, bo_synclist); 1671 syncer_worklist_len--; 1672 mtx_unlock(&sync_mtx); 1673 } 1674 bp->b_flags &= ~B_NEEDSGIANT; 1675 bp->b_vp = NULL; 1676 bp->b_bufobj = NULL; 1677 BO_UNLOCK(bo); 1678 vdrop(vp); 1679 } 1680 1681 /* 1682 * Add an item to the syncer work queue. 1683 */ 1684 static void 1685 vn_syncer_add_to_worklist(struct bufobj *bo, int delay) 1686 { 1687 int queue, slot; 1688 1689 ASSERT_BO_LOCKED(bo); 1690 1691 mtx_lock(&sync_mtx); 1692 if (bo->bo_flag & BO_ONWORKLST) 1693 LIST_REMOVE(bo, bo_synclist); 1694 else { 1695 bo->bo_flag |= BO_ONWORKLST; 1696 syncer_worklist_len++; 1697 } 1698 1699 if (delay > syncer_maxdelay - 2) 1700 delay = syncer_maxdelay - 2; 1701 slot = (syncer_delayno + delay) & syncer_mask; 1702 1703 queue = VFS_NEEDSGIANT(bo->__bo_vnode->v_mount) ? WI_GIANTQ : 1704 WI_MPSAFEQ; 1705 LIST_INSERT_HEAD(&syncer_workitem_pending[queue][slot], bo, 1706 bo_synclist); 1707 mtx_unlock(&sync_mtx); 1708 } 1709 1710 static int 1711 sysctl_vfs_worklist_len(SYSCTL_HANDLER_ARGS) 1712 { 1713 int error, len; 1714 1715 mtx_lock(&sync_mtx); 1716 len = syncer_worklist_len - sync_vnode_count; 1717 mtx_unlock(&sync_mtx); 1718 error = SYSCTL_OUT(req, &len, sizeof(len)); 1719 return (error); 1720 } 1721 1722 SYSCTL_PROC(_vfs, OID_AUTO, worklist_len, CTLTYPE_INT | CTLFLAG_RD, NULL, 0, 1723 sysctl_vfs_worklist_len, "I", "Syncer thread worklist length"); 1724 1725 static struct proc *updateproc; 1726 static void sched_sync(void); 1727 static struct kproc_desc up_kp = { 1728 "syncer", 1729 sched_sync, 1730 &updateproc 1731 }; 1732 SYSINIT(syncer, SI_SUB_KTHREAD_UPDATE, SI_ORDER_FIRST, kproc_start, &up_kp); 1733 1734 static int 1735 sync_vnode(struct synclist *slp, struct bufobj **bo, struct thread *td) 1736 { 1737 struct vnode *vp; 1738 struct mount *mp; 1739 1740 *bo = LIST_FIRST(slp); 1741 if (*bo == NULL) 1742 return (0); 1743 vp = (*bo)->__bo_vnode; /* XXX */ 1744 if (VOP_ISLOCKED(vp) != 0 || VI_TRYLOCK(vp) == 0) 1745 return (1); 1746 /* 1747 * We use vhold in case the vnode does not 1748 * successfully sync. vhold prevents the vnode from 1749 * going away when we unlock the sync_mtx so that 1750 * we can acquire the vnode interlock. 1751 */ 1752 vholdl(vp); 1753 mtx_unlock(&sync_mtx); 1754 VI_UNLOCK(vp); 1755 if (vn_start_write(vp, &mp, V_NOWAIT) != 0) { 1756 vdrop(vp); 1757 mtx_lock(&sync_mtx); 1758 return (*bo == LIST_FIRST(slp)); 1759 } 1760 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 1761 (void) VOP_FSYNC(vp, MNT_LAZY, td); 1762 VOP_UNLOCK(vp, 0); 1763 vn_finished_write(mp); 1764 BO_LOCK(*bo); 1765 if (((*bo)->bo_flag & BO_ONWORKLST) != 0) { 1766 /* 1767 * Put us back on the worklist. The worklist 1768 * routine will remove us from our current 1769 * position and then add us back in at a later 1770 * position. 1771 */ 1772 vn_syncer_add_to_worklist(*bo, syncdelay); 1773 } 1774 BO_UNLOCK(*bo); 1775 vdrop(vp); 1776 mtx_lock(&sync_mtx); 1777 return (0); 1778 } 1779 1780 /* 1781 * System filesystem synchronizer daemon. 1782 */ 1783 static void 1784 sched_sync(void) 1785 { 1786 struct synclist *gnext, *next; 1787 struct synclist *gslp, *slp; 1788 struct bufobj *bo; 1789 long starttime; 1790 struct thread *td = curthread; 1791 int last_work_seen; 1792 int net_worklist_len; 1793 int syncer_final_iter; 1794 int first_printf; 1795 int error; 1796 1797 last_work_seen = 0; 1798 syncer_final_iter = 0; 1799 first_printf = 1; 1800 syncer_state = SYNCER_RUNNING; 1801 starttime = time_uptime; 1802 td->td_pflags |= TDP_NORUNNINGBUF; 1803 1804 EVENTHANDLER_REGISTER(shutdown_pre_sync, syncer_shutdown, td->td_proc, 1805 SHUTDOWN_PRI_LAST); 1806 1807 mtx_lock(&sync_mtx); 1808 for (;;) { 1809 if (syncer_state == SYNCER_FINAL_DELAY && 1810 syncer_final_iter == 0) { 1811 mtx_unlock(&sync_mtx); 1812 kproc_suspend_check(td->td_proc); 1813 mtx_lock(&sync_mtx); 1814 } 1815 net_worklist_len = syncer_worklist_len - sync_vnode_count; 1816 if (syncer_state != SYNCER_RUNNING && 1817 starttime != time_uptime) { 1818 if (first_printf) { 1819 printf("\nSyncing disks, vnodes remaining..."); 1820 first_printf = 0; 1821 } 1822 printf("%d ", net_worklist_len); 1823 } 1824 starttime = time_uptime; 1825 1826 /* 1827 * Push files whose dirty time has expired. Be careful 1828 * of interrupt race on slp queue. 1829 * 1830 * Skip over empty worklist slots when shutting down. 1831 */ 1832 do { 1833 slp = &syncer_workitem_pending[WI_MPSAFEQ][syncer_delayno]; 1834 gslp = &syncer_workitem_pending[WI_GIANTQ][syncer_delayno]; 1835 syncer_delayno += 1; 1836 if (syncer_delayno == syncer_maxdelay) 1837 syncer_delayno = 0; 1838 next = &syncer_workitem_pending[WI_MPSAFEQ][syncer_delayno]; 1839 gnext = &syncer_workitem_pending[WI_GIANTQ][syncer_delayno]; 1840 /* 1841 * If the worklist has wrapped since the 1842 * it was emptied of all but syncer vnodes, 1843 * switch to the FINAL_DELAY state and run 1844 * for one more second. 1845 */ 1846 if (syncer_state == SYNCER_SHUTTING_DOWN && 1847 net_worklist_len == 0 && 1848 last_work_seen == syncer_delayno) { 1849 syncer_state = SYNCER_FINAL_DELAY; 1850 syncer_final_iter = SYNCER_SHUTDOWN_SPEEDUP; 1851 } 1852 } while (syncer_state != SYNCER_RUNNING && LIST_EMPTY(slp) && 1853 LIST_EMPTY(gslp) && syncer_worklist_len > 0); 1854 1855 /* 1856 * Keep track of the last time there was anything 1857 * on the worklist other than syncer vnodes. 1858 * Return to the SHUTTING_DOWN state if any 1859 * new work appears. 1860 */ 1861 if (net_worklist_len > 0 || syncer_state == SYNCER_RUNNING) 1862 last_work_seen = syncer_delayno; 1863 if (net_worklist_len > 0 && syncer_state == SYNCER_FINAL_DELAY) 1864 syncer_state = SYNCER_SHUTTING_DOWN; 1865 while (!LIST_EMPTY(slp)) { 1866 error = sync_vnode(slp, &bo, td); 1867 if (error == 1) { 1868 LIST_REMOVE(bo, bo_synclist); 1869 LIST_INSERT_HEAD(next, bo, bo_synclist); 1870 continue; 1871 } 1872 #ifdef SW_WATCHDOG 1873 if (first_printf == 0) 1874 wdog_kern_pat(WD_LASTVAL); 1875 #endif 1876 } 1877 if (!LIST_EMPTY(gslp)) { 1878 mtx_unlock(&sync_mtx); 1879 mtx_lock(&Giant); 1880 mtx_lock(&sync_mtx); 1881 while (!LIST_EMPTY(gslp)) { 1882 error = sync_vnode(gslp, &bo, td); 1883 if (error == 1) { 1884 LIST_REMOVE(bo, bo_synclist); 1885 LIST_INSERT_HEAD(gnext, bo, 1886 bo_synclist); 1887 continue; 1888 } 1889 } 1890 mtx_unlock(&Giant); 1891 } 1892 if (syncer_state == SYNCER_FINAL_DELAY && syncer_final_iter > 0) 1893 syncer_final_iter--; 1894 /* 1895 * The variable rushjob allows the kernel to speed up the 1896 * processing of the filesystem syncer process. A rushjob 1897 * value of N tells the filesystem syncer to process the next 1898 * N seconds worth of work on its queue ASAP. Currently rushjob 1899 * is used by the soft update code to speed up the filesystem 1900 * syncer process when the incore state is getting so far 1901 * ahead of the disk that the kernel memory pool is being 1902 * threatened with exhaustion. 1903 */ 1904 if (rushjob > 0) { 1905 rushjob -= 1; 1906 continue; 1907 } 1908 /* 1909 * Just sleep for a short period of time between 1910 * iterations when shutting down to allow some I/O 1911 * to happen. 1912 * 1913 * If it has taken us less than a second to process the 1914 * current work, then wait. Otherwise start right over 1915 * again. We can still lose time if any single round 1916 * takes more than two seconds, but it does not really 1917 * matter as we are just trying to generally pace the 1918 * filesystem activity. 1919 */ 1920 if (syncer_state != SYNCER_RUNNING || 1921 time_uptime == starttime) { 1922 thread_lock(td); 1923 sched_prio(td, PPAUSE); 1924 thread_unlock(td); 1925 } 1926 if (syncer_state != SYNCER_RUNNING) 1927 cv_timedwait(&sync_wakeup, &sync_mtx, 1928 hz / SYNCER_SHUTDOWN_SPEEDUP); 1929 else if (time_uptime == starttime) 1930 cv_timedwait(&sync_wakeup, &sync_mtx, hz); 1931 } 1932 } 1933 1934 /* 1935 * Request the syncer daemon to speed up its work. 1936 * We never push it to speed up more than half of its 1937 * normal turn time, otherwise it could take over the cpu. 1938 */ 1939 int 1940 speedup_syncer(void) 1941 { 1942 int ret = 0; 1943 1944 mtx_lock(&sync_mtx); 1945 if (rushjob < syncdelay / 2) { 1946 rushjob += 1; 1947 stat_rush_requests += 1; 1948 ret = 1; 1949 } 1950 mtx_unlock(&sync_mtx); 1951 cv_broadcast(&sync_wakeup); 1952 return (ret); 1953 } 1954 1955 /* 1956 * Tell the syncer to speed up its work and run though its work 1957 * list several times, then tell it to shut down. 1958 */ 1959 static void 1960 syncer_shutdown(void *arg, int howto) 1961 { 1962 1963 if (howto & RB_NOSYNC) 1964 return; 1965 mtx_lock(&sync_mtx); 1966 syncer_state = SYNCER_SHUTTING_DOWN; 1967 rushjob = 0; 1968 mtx_unlock(&sync_mtx); 1969 cv_broadcast(&sync_wakeup); 1970 kproc_shutdown(arg, howto); 1971 } 1972 1973 /* 1974 * Reassign a buffer from one vnode to another. 1975 * Used to assign file specific control information 1976 * (indirect blocks) to the vnode to which they belong. 1977 */ 1978 void 1979 reassignbuf(struct buf *bp) 1980 { 1981 struct vnode *vp; 1982 struct bufobj *bo; 1983 int delay; 1984 #ifdef INVARIANTS 1985 struct bufv *bv; 1986 #endif 1987 1988 vp = bp->b_vp; 1989 bo = bp->b_bufobj; 1990 ++reassignbufcalls; 1991 1992 CTR3(KTR_BUF, "reassignbuf(%p) vp %p flags %X", 1993 bp, bp->b_vp, bp->b_flags); 1994 /* 1995 * B_PAGING flagged buffers cannot be reassigned because their vp 1996 * is not fully linked in. 1997 */ 1998 if (bp->b_flags & B_PAGING) 1999 panic("cannot reassign paging buffer"); 2000 2001 /* 2002 * Delete from old vnode list, if on one. 2003 */ 2004 BO_LOCK(bo); 2005 if (bp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN)) 2006 buf_vlist_remove(bp); 2007 else 2008 panic("reassignbuf: Buffer %p not on queue.", bp); 2009 /* 2010 * If dirty, put on list of dirty buffers; otherwise insert onto list 2011 * of clean buffers. 2012 */ 2013 if (bp->b_flags & B_DELWRI) { 2014 if ((bo->bo_flag & BO_ONWORKLST) == 0) { 2015 switch (vp->v_type) { 2016 case VDIR: 2017 delay = dirdelay; 2018 break; 2019 case VCHR: 2020 delay = metadelay; 2021 break; 2022 default: 2023 delay = filedelay; 2024 } 2025 vn_syncer_add_to_worklist(bo, delay); 2026 } 2027 buf_vlist_add(bp, bo, BX_VNDIRTY); 2028 } else { 2029 buf_vlist_add(bp, bo, BX_VNCLEAN); 2030 2031 if ((bo->bo_flag & BO_ONWORKLST) && bo->bo_dirty.bv_cnt == 0) { 2032 mtx_lock(&sync_mtx); 2033 LIST_REMOVE(bo, bo_synclist); 2034 syncer_worklist_len--; 2035 mtx_unlock(&sync_mtx); 2036 bo->bo_flag &= ~BO_ONWORKLST; 2037 } 2038 } 2039 #ifdef INVARIANTS 2040 bv = &bo->bo_clean; 2041 bp = TAILQ_FIRST(&bv->bv_hd); 2042 KASSERT(bp == NULL || bp->b_bufobj == bo, 2043 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 2044 bp = TAILQ_LAST(&bv->bv_hd, buflists); 2045 KASSERT(bp == NULL || bp->b_bufobj == bo, 2046 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 2047 bv = &bo->bo_dirty; 2048 bp = TAILQ_FIRST(&bv->bv_hd); 2049 KASSERT(bp == NULL || bp->b_bufobj == bo, 2050 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 2051 bp = TAILQ_LAST(&bv->bv_hd, buflists); 2052 KASSERT(bp == NULL || bp->b_bufobj == bo, 2053 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 2054 #endif 2055 BO_UNLOCK(bo); 2056 } 2057 2058 /* 2059 * Increment the use and hold counts on the vnode, taking care to reference 2060 * the driver's usecount if this is a chardev. The vholdl() will remove 2061 * the vnode from the free list if it is presently free. Requires the 2062 * vnode interlock and returns with it held. 2063 */ 2064 static void 2065 v_incr_usecount(struct vnode *vp) 2066 { 2067 2068 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2069 vp->v_usecount++; 2070 if (vp->v_type == VCHR && vp->v_rdev != NULL) { 2071 dev_lock(); 2072 vp->v_rdev->si_usecount++; 2073 dev_unlock(); 2074 } 2075 vholdl(vp); 2076 } 2077 2078 /* 2079 * Turn a holdcnt into a use+holdcnt such that only one call to 2080 * v_decr_usecount is needed. 2081 */ 2082 static void 2083 v_upgrade_usecount(struct vnode *vp) 2084 { 2085 2086 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2087 vp->v_usecount++; 2088 if (vp->v_type == VCHR && vp->v_rdev != NULL) { 2089 dev_lock(); 2090 vp->v_rdev->si_usecount++; 2091 dev_unlock(); 2092 } 2093 } 2094 2095 /* 2096 * Decrement the vnode use and hold count along with the driver's usecount 2097 * if this is a chardev. The vdropl() below releases the vnode interlock 2098 * as it may free the vnode. 2099 */ 2100 static void 2101 v_decr_usecount(struct vnode *vp) 2102 { 2103 2104 ASSERT_VI_LOCKED(vp, __FUNCTION__); 2105 VNASSERT(vp->v_usecount > 0, vp, 2106 ("v_decr_usecount: negative usecount")); 2107 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2108 vp->v_usecount--; 2109 if (vp->v_type == VCHR && vp->v_rdev != NULL) { 2110 dev_lock(); 2111 vp->v_rdev->si_usecount--; 2112 dev_unlock(); 2113 } 2114 vdropl(vp); 2115 } 2116 2117 /* 2118 * Decrement only the use count and driver use count. This is intended to 2119 * be paired with a follow on vdropl() to release the remaining hold count. 2120 * In this way we may vgone() a vnode with a 0 usecount without risk of 2121 * having it end up on a free list because the hold count is kept above 0. 2122 */ 2123 static void 2124 v_decr_useonly(struct vnode *vp) 2125 { 2126 2127 ASSERT_VI_LOCKED(vp, __FUNCTION__); 2128 VNASSERT(vp->v_usecount > 0, vp, 2129 ("v_decr_useonly: negative usecount")); 2130 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2131 vp->v_usecount--; 2132 if (vp->v_type == VCHR && vp->v_rdev != NULL) { 2133 dev_lock(); 2134 vp->v_rdev->si_usecount--; 2135 dev_unlock(); 2136 } 2137 } 2138 2139 /* 2140 * Grab a particular vnode from the free list, increment its 2141 * reference count and lock it. VI_DOOMED is set if the vnode 2142 * is being destroyed. Only callers who specify LK_RETRY will 2143 * see doomed vnodes. If inactive processing was delayed in 2144 * vput try to do it here. 2145 */ 2146 int 2147 vget(struct vnode *vp, int flags, struct thread *td) 2148 { 2149 int error; 2150 2151 error = 0; 2152 VFS_ASSERT_GIANT(vp->v_mount); 2153 VNASSERT((flags & LK_TYPE_MASK) != 0, vp, 2154 ("vget: invalid lock operation")); 2155 CTR3(KTR_VFS, "%s: vp %p with flags %d", __func__, vp, flags); 2156 2157 if ((flags & LK_INTERLOCK) == 0) 2158 VI_LOCK(vp); 2159 vholdl(vp); 2160 if ((error = vn_lock(vp, flags | LK_INTERLOCK)) != 0) { 2161 vdrop(vp); 2162 CTR2(KTR_VFS, "%s: impossible to lock vnode %p", __func__, 2163 vp); 2164 return (error); 2165 } 2166 if (vp->v_iflag & VI_DOOMED && (flags & LK_RETRY) == 0) 2167 panic("vget: vn_lock failed to return ENOENT\n"); 2168 VI_LOCK(vp); 2169 /* Upgrade our holdcnt to a usecount. */ 2170 v_upgrade_usecount(vp); 2171 /* 2172 * We don't guarantee that any particular close will 2173 * trigger inactive processing so just make a best effort 2174 * here at preventing a reference to a removed file. If 2175 * we don't succeed no harm is done. 2176 */ 2177 if (vp->v_iflag & VI_OWEINACT) { 2178 if (VOP_ISLOCKED(vp) == LK_EXCLUSIVE && 2179 (flags & LK_NOWAIT) == 0) 2180 vinactive(vp, td); 2181 vp->v_iflag &= ~VI_OWEINACT; 2182 } 2183 VI_UNLOCK(vp); 2184 return (0); 2185 } 2186 2187 /* 2188 * Increase the reference count of a vnode. 2189 */ 2190 void 2191 vref(struct vnode *vp) 2192 { 2193 2194 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2195 VI_LOCK(vp); 2196 v_incr_usecount(vp); 2197 VI_UNLOCK(vp); 2198 } 2199 2200 /* 2201 * Return reference count of a vnode. 2202 * 2203 * The results of this call are only guaranteed when some mechanism other 2204 * than the VI lock is used to stop other processes from gaining references 2205 * to the vnode. This may be the case if the caller holds the only reference. 2206 * This is also useful when stale data is acceptable as race conditions may 2207 * be accounted for by some other means. 2208 */ 2209 int 2210 vrefcnt(struct vnode *vp) 2211 { 2212 int usecnt; 2213 2214 VI_LOCK(vp); 2215 usecnt = vp->v_usecount; 2216 VI_UNLOCK(vp); 2217 2218 return (usecnt); 2219 } 2220 2221 #define VPUTX_VRELE 1 2222 #define VPUTX_VPUT 2 2223 #define VPUTX_VUNREF 3 2224 2225 static void 2226 vputx(struct vnode *vp, int func) 2227 { 2228 int error; 2229 2230 KASSERT(vp != NULL, ("vputx: null vp")); 2231 if (func == VPUTX_VUNREF) 2232 ASSERT_VOP_LOCKED(vp, "vunref"); 2233 else if (func == VPUTX_VPUT) 2234 ASSERT_VOP_LOCKED(vp, "vput"); 2235 else 2236 KASSERT(func == VPUTX_VRELE, ("vputx: wrong func")); 2237 VFS_ASSERT_GIANT(vp->v_mount); 2238 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2239 VI_LOCK(vp); 2240 2241 /* Skip this v_writecount check if we're going to panic below. */ 2242 VNASSERT(vp->v_writecount < vp->v_usecount || vp->v_usecount < 1, vp, 2243 ("vputx: missed vn_close")); 2244 error = 0; 2245 2246 if (vp->v_usecount > 1 || ((vp->v_iflag & VI_DOINGINACT) && 2247 vp->v_usecount == 1)) { 2248 if (func == VPUTX_VPUT) 2249 VOP_UNLOCK(vp, 0); 2250 v_decr_usecount(vp); 2251 return; 2252 } 2253 2254 if (vp->v_usecount != 1) { 2255 vprint("vputx: negative ref count", vp); 2256 panic("vputx: negative ref cnt"); 2257 } 2258 CTR2(KTR_VFS, "%s: return vnode %p to the freelist", __func__, vp); 2259 /* 2260 * We want to hold the vnode until the inactive finishes to 2261 * prevent vgone() races. We drop the use count here and the 2262 * hold count below when we're done. 2263 */ 2264 v_decr_useonly(vp); 2265 /* 2266 * We must call VOP_INACTIVE with the node locked. Mark 2267 * as VI_DOINGINACT to avoid recursion. 2268 */ 2269 vp->v_iflag |= VI_OWEINACT; 2270 switch (func) { 2271 case VPUTX_VRELE: 2272 error = vn_lock(vp, LK_EXCLUSIVE | LK_INTERLOCK); 2273 VI_LOCK(vp); 2274 break; 2275 case VPUTX_VPUT: 2276 if (VOP_ISLOCKED(vp) != LK_EXCLUSIVE) { 2277 error = VOP_LOCK(vp, LK_UPGRADE | LK_INTERLOCK | 2278 LK_NOWAIT); 2279 VI_LOCK(vp); 2280 } 2281 break; 2282 case VPUTX_VUNREF: 2283 if (VOP_ISLOCKED(vp) != LK_EXCLUSIVE) 2284 error = EBUSY; 2285 break; 2286 } 2287 if (vp->v_usecount > 0) 2288 vp->v_iflag &= ~VI_OWEINACT; 2289 if (error == 0) { 2290 if (vp->v_iflag & VI_OWEINACT) 2291 vinactive(vp, curthread); 2292 if (func != VPUTX_VUNREF) 2293 VOP_UNLOCK(vp, 0); 2294 } 2295 vdropl(vp); 2296 } 2297 2298 /* 2299 * Vnode put/release. 2300 * If count drops to zero, call inactive routine and return to freelist. 2301 */ 2302 void 2303 vrele(struct vnode *vp) 2304 { 2305 2306 vputx(vp, VPUTX_VRELE); 2307 } 2308 2309 /* 2310 * Release an already locked vnode. This give the same effects as 2311 * unlock+vrele(), but takes less time and avoids releasing and 2312 * re-aquiring the lock (as vrele() acquires the lock internally.) 2313 */ 2314 void 2315 vput(struct vnode *vp) 2316 { 2317 2318 vputx(vp, VPUTX_VPUT); 2319 } 2320 2321 /* 2322 * Release an exclusively locked vnode. Do not unlock the vnode lock. 2323 */ 2324 void 2325 vunref(struct vnode *vp) 2326 { 2327 2328 vputx(vp, VPUTX_VUNREF); 2329 } 2330 2331 /* 2332 * Somebody doesn't want the vnode recycled. 2333 */ 2334 void 2335 vhold(struct vnode *vp) 2336 { 2337 2338 VI_LOCK(vp); 2339 vholdl(vp); 2340 VI_UNLOCK(vp); 2341 } 2342 2343 /* 2344 * Increase the hold count and activate if this is the first reference. 2345 */ 2346 void 2347 vholdl(struct vnode *vp) 2348 { 2349 struct mount *mp; 2350 2351 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2352 vp->v_holdcnt++; 2353 if (!VSHOULDBUSY(vp)) 2354 return; 2355 ASSERT_VI_LOCKED(vp, "vholdl"); 2356 VNASSERT((vp->v_iflag & VI_FREE) != 0, vp, ("vnode not free")); 2357 VNASSERT(vp->v_op != NULL, vp, ("vholdl: vnode already reclaimed.")); 2358 /* 2359 * Remove a vnode from the free list, mark it as in use, 2360 * and put it on the active list. 2361 */ 2362 mtx_lock(&vnode_free_list_mtx); 2363 TAILQ_REMOVE(&vnode_free_list, vp, v_actfreelist); 2364 freevnodes--; 2365 vp->v_iflag &= ~(VI_FREE|VI_AGE); 2366 KASSERT((vp->v_iflag & VI_ACTIVE) == 0, 2367 ("Activating already active vnode")); 2368 vp->v_iflag |= VI_ACTIVE; 2369 mp = vp->v_mount; 2370 TAILQ_INSERT_HEAD(&mp->mnt_activevnodelist, vp, v_actfreelist); 2371 mp->mnt_activevnodelistsize++; 2372 mtx_unlock(&vnode_free_list_mtx); 2373 } 2374 2375 /* 2376 * Note that there is one less who cares about this vnode. 2377 * vdrop() is the opposite of vhold(). 2378 */ 2379 void 2380 vdrop(struct vnode *vp) 2381 { 2382 2383 VI_LOCK(vp); 2384 vdropl(vp); 2385 } 2386 2387 /* 2388 * Drop the hold count of the vnode. If this is the last reference to 2389 * the vnode we place it on the free list unless it has been vgone'd 2390 * (marked VI_DOOMED) in which case we will free it. 2391 */ 2392 void 2393 vdropl(struct vnode *vp) 2394 { 2395 struct bufobj *bo; 2396 struct mount *mp; 2397 int active; 2398 2399 ASSERT_VI_LOCKED(vp, "vdropl"); 2400 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2401 if (vp->v_holdcnt <= 0) 2402 panic("vdrop: holdcnt %d", vp->v_holdcnt); 2403 vp->v_holdcnt--; 2404 if (vp->v_holdcnt > 0) { 2405 VI_UNLOCK(vp); 2406 return; 2407 } 2408 if ((vp->v_iflag & VI_DOOMED) == 0) { 2409 /* 2410 * Mark a vnode as free: remove it from its active list 2411 * and put it up for recycling on the freelist. 2412 */ 2413 VNASSERT(vp->v_op != NULL, vp, 2414 ("vdropl: vnode already reclaimed.")); 2415 VNASSERT((vp->v_iflag & VI_FREE) == 0, vp, 2416 ("vnode already free")); 2417 VNASSERT(VSHOULDFREE(vp), vp, 2418 ("vdropl: freeing when we shouldn't")); 2419 active = vp->v_iflag & VI_ACTIVE; 2420 vp->v_iflag &= ~VI_ACTIVE; 2421 mp = vp->v_mount; 2422 mtx_lock(&vnode_free_list_mtx); 2423 if (active) { 2424 TAILQ_REMOVE(&mp->mnt_activevnodelist, vp, 2425 v_actfreelist); 2426 mp->mnt_activevnodelistsize--; 2427 } 2428 if (vp->v_iflag & VI_AGE) { 2429 TAILQ_INSERT_HEAD(&vnode_free_list, vp, v_actfreelist); 2430 } else { 2431 TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_actfreelist); 2432 } 2433 freevnodes++; 2434 vp->v_iflag &= ~VI_AGE; 2435 vp->v_iflag |= VI_FREE; 2436 mtx_unlock(&vnode_free_list_mtx); 2437 VI_UNLOCK(vp); 2438 return; 2439 } 2440 /* 2441 * The vnode has been marked for destruction, so free it. 2442 */ 2443 CTR2(KTR_VFS, "%s: destroying the vnode %p", __func__, vp); 2444 mtx_lock(&vnode_free_list_mtx); 2445 numvnodes--; 2446 mtx_unlock(&vnode_free_list_mtx); 2447 bo = &vp->v_bufobj; 2448 VNASSERT((vp->v_iflag & VI_FREE) == 0, vp, 2449 ("cleaned vnode still on the free list.")); 2450 VNASSERT(vp->v_data == NULL, vp, ("cleaned vnode isn't")); 2451 VNASSERT(vp->v_holdcnt == 0, vp, ("Non-zero hold count")); 2452 VNASSERT(vp->v_usecount == 0, vp, ("Non-zero use count")); 2453 VNASSERT(vp->v_writecount == 0, vp, ("Non-zero write count")); 2454 VNASSERT(bo->bo_numoutput == 0, vp, ("Clean vnode has pending I/O's")); 2455 VNASSERT(bo->bo_clean.bv_cnt == 0, vp, ("cleanbufcnt not 0")); 2456 VNASSERT(bo->bo_clean.bv_root == NULL, vp, ("cleanblkroot not NULL")); 2457 VNASSERT(bo->bo_dirty.bv_cnt == 0, vp, ("dirtybufcnt not 0")); 2458 VNASSERT(bo->bo_dirty.bv_root == NULL, vp, ("dirtyblkroot not NULL")); 2459 VNASSERT(TAILQ_EMPTY(&vp->v_cache_dst), vp, ("vp has namecache dst")); 2460 VNASSERT(LIST_EMPTY(&vp->v_cache_src), vp, ("vp has namecache src")); 2461 VNASSERT(vp->v_cache_dd == NULL, vp, ("vp has namecache for ..")); 2462 VI_UNLOCK(vp); 2463 #ifdef MAC 2464 mac_vnode_destroy(vp); 2465 #endif 2466 if (vp->v_pollinfo != NULL) 2467 destroy_vpollinfo(vp->v_pollinfo); 2468 #ifdef INVARIANTS 2469 /* XXX Elsewhere we detect an already freed vnode via NULL v_op. */ 2470 vp->v_op = NULL; 2471 #endif 2472 rangelock_destroy(&vp->v_rl); 2473 lockdestroy(vp->v_vnlock); 2474 mtx_destroy(&vp->v_interlock); 2475 mtx_destroy(BO_MTX(bo)); 2476 uma_zfree(vnode_zone, vp); 2477 } 2478 2479 /* 2480 * Call VOP_INACTIVE on the vnode and manage the DOINGINACT and OWEINACT 2481 * flags. DOINGINACT prevents us from recursing in calls to vinactive. 2482 * OWEINACT tracks whether a vnode missed a call to inactive due to a 2483 * failed lock upgrade. 2484 */ 2485 void 2486 vinactive(struct vnode *vp, struct thread *td) 2487 { 2488 struct vm_object *obj; 2489 2490 ASSERT_VOP_ELOCKED(vp, "vinactive"); 2491 ASSERT_VI_LOCKED(vp, "vinactive"); 2492 VNASSERT((vp->v_iflag & VI_DOINGINACT) == 0, vp, 2493 ("vinactive: recursed on VI_DOINGINACT")); 2494 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2495 vp->v_iflag |= VI_DOINGINACT; 2496 vp->v_iflag &= ~VI_OWEINACT; 2497 VI_UNLOCK(vp); 2498 /* 2499 * Before moving off the active list, we must be sure that any 2500 * modified pages are on the vnode's dirty list since these will 2501 * no longer be checked once the vnode is on the inactive list. 2502 */ 2503 obj = vp->v_object; 2504 if (obj != NULL && (obj->flags & OBJ_MIGHTBEDIRTY) != 0) { 2505 VM_OBJECT_LOCK(obj); 2506 vm_object_page_clean(obj, 0, 0, OBJPC_NOSYNC); 2507 VM_OBJECT_UNLOCK(obj); 2508 } 2509 VOP_INACTIVE(vp, td); 2510 VI_LOCK(vp); 2511 VNASSERT(vp->v_iflag & VI_DOINGINACT, vp, 2512 ("vinactive: lost VI_DOINGINACT")); 2513 vp->v_iflag &= ~VI_DOINGINACT; 2514 } 2515 2516 /* 2517 * Remove any vnodes in the vnode table belonging to mount point mp. 2518 * 2519 * If FORCECLOSE is not specified, there should not be any active ones, 2520 * return error if any are found (nb: this is a user error, not a 2521 * system error). If FORCECLOSE is specified, detach any active vnodes 2522 * that are found. 2523 * 2524 * If WRITECLOSE is set, only flush out regular file vnodes open for 2525 * writing. 2526 * 2527 * SKIPSYSTEM causes any vnodes marked VV_SYSTEM to be skipped. 2528 * 2529 * `rootrefs' specifies the base reference count for the root vnode 2530 * of this filesystem. The root vnode is considered busy if its 2531 * v_usecount exceeds this value. On a successful return, vflush(, td) 2532 * will call vrele() on the root vnode exactly rootrefs times. 2533 * If the SKIPSYSTEM or WRITECLOSE flags are specified, rootrefs must 2534 * be zero. 2535 */ 2536 #ifdef DIAGNOSTIC 2537 static int busyprt = 0; /* print out busy vnodes */ 2538 SYSCTL_INT(_debug, OID_AUTO, busyprt, CTLFLAG_RW, &busyprt, 0, "Print out busy vnodes"); 2539 #endif 2540 2541 int 2542 vflush(struct mount *mp, int rootrefs, int flags, struct thread *td) 2543 { 2544 struct vnode *vp, *mvp, *rootvp = NULL; 2545 struct vattr vattr; 2546 int busy = 0, error; 2547 2548 CTR4(KTR_VFS, "%s: mp %p with rootrefs %d and flags %d", __func__, mp, 2549 rootrefs, flags); 2550 if (rootrefs > 0) { 2551 KASSERT((flags & (SKIPSYSTEM | WRITECLOSE)) == 0, 2552 ("vflush: bad args")); 2553 /* 2554 * Get the filesystem root vnode. We can vput() it 2555 * immediately, since with rootrefs > 0, it won't go away. 2556 */ 2557 if ((error = VFS_ROOT(mp, LK_EXCLUSIVE, &rootvp)) != 0) { 2558 CTR2(KTR_VFS, "%s: vfs_root lookup failed with %d", 2559 __func__, error); 2560 return (error); 2561 } 2562 vput(rootvp); 2563 } 2564 loop: 2565 MNT_VNODE_FOREACH_ALL(vp, mp, mvp) { 2566 vholdl(vp); 2567 error = vn_lock(vp, LK_INTERLOCK | LK_EXCLUSIVE); 2568 if (error) { 2569 vdrop(vp); 2570 MNT_VNODE_FOREACH_ALL_ABORT(mp, mvp); 2571 goto loop; 2572 } 2573 /* 2574 * Skip over a vnodes marked VV_SYSTEM. 2575 */ 2576 if ((flags & SKIPSYSTEM) && (vp->v_vflag & VV_SYSTEM)) { 2577 VOP_UNLOCK(vp, 0); 2578 vdrop(vp); 2579 continue; 2580 } 2581 /* 2582 * If WRITECLOSE is set, flush out unlinked but still open 2583 * files (even if open only for reading) and regular file 2584 * vnodes open for writing. 2585 */ 2586 if (flags & WRITECLOSE) { 2587 if (vp->v_object != NULL) { 2588 VM_OBJECT_LOCK(vp->v_object); 2589 vm_object_page_clean(vp->v_object, 0, 0, 0); 2590 VM_OBJECT_UNLOCK(vp->v_object); 2591 } 2592 error = VOP_FSYNC(vp, MNT_WAIT, td); 2593 if (error != 0) { 2594 VOP_UNLOCK(vp, 0); 2595 vdrop(vp); 2596 MNT_VNODE_FOREACH_ALL_ABORT(mp, mvp); 2597 return (error); 2598 } 2599 error = VOP_GETATTR(vp, &vattr, td->td_ucred); 2600 VI_LOCK(vp); 2601 2602 if ((vp->v_type == VNON || 2603 (error == 0 && vattr.va_nlink > 0)) && 2604 (vp->v_writecount == 0 || vp->v_type != VREG)) { 2605 VOP_UNLOCK(vp, 0); 2606 vdropl(vp); 2607 continue; 2608 } 2609 } else 2610 VI_LOCK(vp); 2611 /* 2612 * With v_usecount == 0, all we need to do is clear out the 2613 * vnode data structures and we are done. 2614 * 2615 * If FORCECLOSE is set, forcibly close the vnode. 2616 */ 2617 if (vp->v_usecount == 0 || (flags & FORCECLOSE)) { 2618 VNASSERT(vp->v_usecount == 0 || 2619 (vp->v_type != VCHR && vp->v_type != VBLK), vp, 2620 ("device VNODE %p is FORCECLOSED", vp)); 2621 vgonel(vp); 2622 } else { 2623 busy++; 2624 #ifdef DIAGNOSTIC 2625 if (busyprt) 2626 vprint("vflush: busy vnode", vp); 2627 #endif 2628 } 2629 VOP_UNLOCK(vp, 0); 2630 vdropl(vp); 2631 } 2632 if (rootrefs > 0 && (flags & FORCECLOSE) == 0) { 2633 /* 2634 * If just the root vnode is busy, and if its refcount 2635 * is equal to `rootrefs', then go ahead and kill it. 2636 */ 2637 VI_LOCK(rootvp); 2638 KASSERT(busy > 0, ("vflush: not busy")); 2639 VNASSERT(rootvp->v_usecount >= rootrefs, rootvp, 2640 ("vflush: usecount %d < rootrefs %d", 2641 rootvp->v_usecount, rootrefs)); 2642 if (busy == 1 && rootvp->v_usecount == rootrefs) { 2643 VOP_LOCK(rootvp, LK_EXCLUSIVE|LK_INTERLOCK); 2644 vgone(rootvp); 2645 VOP_UNLOCK(rootvp, 0); 2646 busy = 0; 2647 } else 2648 VI_UNLOCK(rootvp); 2649 } 2650 if (busy) { 2651 CTR2(KTR_VFS, "%s: failing as %d vnodes are busy", __func__, 2652 busy); 2653 return (EBUSY); 2654 } 2655 for (; rootrefs > 0; rootrefs--) 2656 vrele(rootvp); 2657 return (0); 2658 } 2659 2660 /* 2661 * Recycle an unused vnode to the front of the free list. 2662 */ 2663 int 2664 vrecycle(struct vnode *vp) 2665 { 2666 int recycled; 2667 2668 ASSERT_VOP_ELOCKED(vp, "vrecycle"); 2669 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2670 recycled = 0; 2671 VI_LOCK(vp); 2672 if (vp->v_usecount == 0) { 2673 recycled = 1; 2674 vgonel(vp); 2675 } 2676 VI_UNLOCK(vp); 2677 return (recycled); 2678 } 2679 2680 /* 2681 * Eliminate all activity associated with a vnode 2682 * in preparation for reuse. 2683 */ 2684 void 2685 vgone(struct vnode *vp) 2686 { 2687 VI_LOCK(vp); 2688 vgonel(vp); 2689 VI_UNLOCK(vp); 2690 } 2691 2692 /* 2693 * vgone, with the vp interlock held. 2694 */ 2695 void 2696 vgonel(struct vnode *vp) 2697 { 2698 struct thread *td; 2699 int oweinact; 2700 int active; 2701 struct mount *mp; 2702 2703 ASSERT_VOP_ELOCKED(vp, "vgonel"); 2704 ASSERT_VI_LOCKED(vp, "vgonel"); 2705 VNASSERT(vp->v_holdcnt, vp, 2706 ("vgonel: vp %p has no reference.", vp)); 2707 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2708 td = curthread; 2709 2710 /* 2711 * Don't vgonel if we're already doomed. 2712 */ 2713 if (vp->v_iflag & VI_DOOMED) 2714 return; 2715 vp->v_iflag |= VI_DOOMED; 2716 /* 2717 * Check to see if the vnode is in use. If so, we have to call 2718 * VOP_CLOSE() and VOP_INACTIVE(). 2719 */ 2720 active = vp->v_usecount; 2721 oweinact = (vp->v_iflag & VI_OWEINACT); 2722 VI_UNLOCK(vp); 2723 /* 2724 * Clean out any buffers associated with the vnode. 2725 * If the flush fails, just toss the buffers. 2726 */ 2727 mp = NULL; 2728 if (!TAILQ_EMPTY(&vp->v_bufobj.bo_dirty.bv_hd)) 2729 (void) vn_start_secondary_write(vp, &mp, V_WAIT); 2730 if (vinvalbuf(vp, V_SAVE, 0, 0) != 0) 2731 vinvalbuf(vp, 0, 0, 0); 2732 2733 /* 2734 * If purging an active vnode, it must be closed and 2735 * deactivated before being reclaimed. 2736 */ 2737 if (active) 2738 VOP_CLOSE(vp, FNONBLOCK, NOCRED, td); 2739 if (oweinact || active) { 2740 VI_LOCK(vp); 2741 if ((vp->v_iflag & VI_DOINGINACT) == 0) 2742 vinactive(vp, td); 2743 VI_UNLOCK(vp); 2744 } 2745 if (vp->v_type == VSOCK) 2746 vfs_unp_reclaim(vp); 2747 /* 2748 * Reclaim the vnode. 2749 */ 2750 if (VOP_RECLAIM(vp, td)) 2751 panic("vgone: cannot reclaim"); 2752 if (mp != NULL) 2753 vn_finished_secondary_write(mp); 2754 VNASSERT(vp->v_object == NULL, vp, 2755 ("vop_reclaim left v_object vp=%p, tag=%s", vp, vp->v_tag)); 2756 /* 2757 * Clear the advisory locks and wake up waiting threads. 2758 */ 2759 (void)VOP_ADVLOCKPURGE(vp); 2760 /* 2761 * Delete from old mount point vnode list. 2762 */ 2763 delmntque(vp); 2764 cache_purge(vp); 2765 /* 2766 * Done with purge, reset to the standard lock and invalidate 2767 * the vnode. 2768 */ 2769 VI_LOCK(vp); 2770 vp->v_vnlock = &vp->v_lock; 2771 vp->v_op = &dead_vnodeops; 2772 vp->v_tag = "none"; 2773 vp->v_type = VBAD; 2774 } 2775 2776 /* 2777 * Calculate the total number of references to a special device. 2778 */ 2779 int 2780 vcount(struct vnode *vp) 2781 { 2782 int count; 2783 2784 dev_lock(); 2785 count = vp->v_rdev->si_usecount; 2786 dev_unlock(); 2787 return (count); 2788 } 2789 2790 /* 2791 * Same as above, but using the struct cdev *as argument 2792 */ 2793 int 2794 count_dev(struct cdev *dev) 2795 { 2796 int count; 2797 2798 dev_lock(); 2799 count = dev->si_usecount; 2800 dev_unlock(); 2801 return(count); 2802 } 2803 2804 /* 2805 * Print out a description of a vnode. 2806 */ 2807 static char *typename[] = 2808 {"VNON", "VREG", "VDIR", "VBLK", "VCHR", "VLNK", "VSOCK", "VFIFO", "VBAD", 2809 "VMARKER"}; 2810 2811 void 2812 vn_printf(struct vnode *vp, const char *fmt, ...) 2813 { 2814 va_list ap; 2815 char buf[256], buf2[16]; 2816 u_long flags; 2817 2818 va_start(ap, fmt); 2819 vprintf(fmt, ap); 2820 va_end(ap); 2821 printf("%p: ", (void *)vp); 2822 printf("tag %s, type %s\n", vp->v_tag, typename[vp->v_type]); 2823 printf(" usecount %d, writecount %d, refcount %d mountedhere %p\n", 2824 vp->v_usecount, vp->v_writecount, vp->v_holdcnt, vp->v_mountedhere); 2825 buf[0] = '\0'; 2826 buf[1] = '\0'; 2827 if (vp->v_vflag & VV_ROOT) 2828 strlcat(buf, "|VV_ROOT", sizeof(buf)); 2829 if (vp->v_vflag & VV_ISTTY) 2830 strlcat(buf, "|VV_ISTTY", sizeof(buf)); 2831 if (vp->v_vflag & VV_NOSYNC) 2832 strlcat(buf, "|VV_NOSYNC", sizeof(buf)); 2833 if (vp->v_vflag & VV_CACHEDLABEL) 2834 strlcat(buf, "|VV_CACHEDLABEL", sizeof(buf)); 2835 if (vp->v_vflag & VV_TEXT) 2836 strlcat(buf, "|VV_TEXT", sizeof(buf)); 2837 if (vp->v_vflag & VV_COPYONWRITE) 2838 strlcat(buf, "|VV_COPYONWRITE", sizeof(buf)); 2839 if (vp->v_vflag & VV_SYSTEM) 2840 strlcat(buf, "|VV_SYSTEM", sizeof(buf)); 2841 if (vp->v_vflag & VV_PROCDEP) 2842 strlcat(buf, "|VV_PROCDEP", sizeof(buf)); 2843 if (vp->v_vflag & VV_NOKNOTE) 2844 strlcat(buf, "|VV_NOKNOTE", sizeof(buf)); 2845 if (vp->v_vflag & VV_DELETED) 2846 strlcat(buf, "|VV_DELETED", sizeof(buf)); 2847 if (vp->v_vflag & VV_MD) 2848 strlcat(buf, "|VV_MD", sizeof(buf)); 2849 flags = vp->v_vflag & ~(VV_ROOT | VV_ISTTY | VV_NOSYNC | 2850 VV_CACHEDLABEL | VV_TEXT | VV_COPYONWRITE | VV_SYSTEM | VV_PROCDEP | 2851 VV_NOKNOTE | VV_DELETED | VV_MD); 2852 if (flags != 0) { 2853 snprintf(buf2, sizeof(buf2), "|VV(0x%lx)", flags); 2854 strlcat(buf, buf2, sizeof(buf)); 2855 } 2856 if (vp->v_iflag & VI_MOUNT) 2857 strlcat(buf, "|VI_MOUNT", sizeof(buf)); 2858 if (vp->v_iflag & VI_AGE) 2859 strlcat(buf, "|VI_AGE", sizeof(buf)); 2860 if (vp->v_iflag & VI_DOOMED) 2861 strlcat(buf, "|VI_DOOMED", sizeof(buf)); 2862 if (vp->v_iflag & VI_FREE) 2863 strlcat(buf, "|VI_FREE", sizeof(buf)); 2864 if (vp->v_iflag & VI_DOINGINACT) 2865 strlcat(buf, "|VI_DOINGINACT", sizeof(buf)); 2866 if (vp->v_iflag & VI_OWEINACT) 2867 strlcat(buf, "|VI_OWEINACT", sizeof(buf)); 2868 flags = vp->v_iflag & ~(VI_MOUNT | VI_AGE | VI_DOOMED | VI_FREE | 2869 VI_DOINGINACT | VI_OWEINACT); 2870 if (flags != 0) { 2871 snprintf(buf2, sizeof(buf2), "|VI(0x%lx)", flags); 2872 strlcat(buf, buf2, sizeof(buf)); 2873 } 2874 printf(" flags (%s)\n", buf + 1); 2875 if (mtx_owned(VI_MTX(vp))) 2876 printf(" VI_LOCKed"); 2877 if (vp->v_object != NULL) 2878 printf(" v_object %p ref %d pages %d\n", 2879 vp->v_object, vp->v_object->ref_count, 2880 vp->v_object->resident_page_count); 2881 printf(" "); 2882 lockmgr_printinfo(vp->v_vnlock); 2883 if (vp->v_data != NULL) 2884 VOP_PRINT(vp); 2885 } 2886 2887 #ifdef DDB 2888 /* 2889 * List all of the locked vnodes in the system. 2890 * Called when debugging the kernel. 2891 */ 2892 DB_SHOW_COMMAND(lockedvnods, lockedvnodes) 2893 { 2894 struct mount *mp, *nmp; 2895 struct vnode *vp; 2896 2897 /* 2898 * Note: because this is DDB, we can't obey the locking semantics 2899 * for these structures, which means we could catch an inconsistent 2900 * state and dereference a nasty pointer. Not much to be done 2901 * about that. 2902 */ 2903 db_printf("Locked vnodes\n"); 2904 for (mp = TAILQ_FIRST(&mountlist); mp != NULL; mp = nmp) { 2905 nmp = TAILQ_NEXT(mp, mnt_list); 2906 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) { 2907 if (vp->v_type != VMARKER && 2908 VOP_ISLOCKED(vp)) 2909 vprint("", vp); 2910 } 2911 nmp = TAILQ_NEXT(mp, mnt_list); 2912 } 2913 } 2914 2915 /* 2916 * Show details about the given vnode. 2917 */ 2918 DB_SHOW_COMMAND(vnode, db_show_vnode) 2919 { 2920 struct vnode *vp; 2921 2922 if (!have_addr) 2923 return; 2924 vp = (struct vnode *)addr; 2925 vn_printf(vp, "vnode "); 2926 } 2927 2928 /* 2929 * Show details about the given mount point. 2930 */ 2931 DB_SHOW_COMMAND(mount, db_show_mount) 2932 { 2933 struct mount *mp; 2934 struct vfsopt *opt; 2935 struct statfs *sp; 2936 struct vnode *vp; 2937 char buf[512]; 2938 uint64_t mflags; 2939 u_int flags; 2940 2941 if (!have_addr) { 2942 /* No address given, print short info about all mount points. */ 2943 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 2944 db_printf("%p %s on %s (%s)\n", mp, 2945 mp->mnt_stat.f_mntfromname, 2946 mp->mnt_stat.f_mntonname, 2947 mp->mnt_stat.f_fstypename); 2948 if (db_pager_quit) 2949 break; 2950 } 2951 db_printf("\nMore info: show mount <addr>\n"); 2952 return; 2953 } 2954 2955 mp = (struct mount *)addr; 2956 db_printf("%p %s on %s (%s)\n", mp, mp->mnt_stat.f_mntfromname, 2957 mp->mnt_stat.f_mntonname, mp->mnt_stat.f_fstypename); 2958 2959 buf[0] = '\0'; 2960 mflags = mp->mnt_flag; 2961 #define MNT_FLAG(flag) do { \ 2962 if (mflags & (flag)) { \ 2963 if (buf[0] != '\0') \ 2964 strlcat(buf, ", ", sizeof(buf)); \ 2965 strlcat(buf, (#flag) + 4, sizeof(buf)); \ 2966 mflags &= ~(flag); \ 2967 } \ 2968 } while (0) 2969 MNT_FLAG(MNT_RDONLY); 2970 MNT_FLAG(MNT_SYNCHRONOUS); 2971 MNT_FLAG(MNT_NOEXEC); 2972 MNT_FLAG(MNT_NOSUID); 2973 MNT_FLAG(MNT_UNION); 2974 MNT_FLAG(MNT_ASYNC); 2975 MNT_FLAG(MNT_SUIDDIR); 2976 MNT_FLAG(MNT_SOFTDEP); 2977 MNT_FLAG(MNT_SUJ); 2978 MNT_FLAG(MNT_NOSYMFOLLOW); 2979 MNT_FLAG(MNT_GJOURNAL); 2980 MNT_FLAG(MNT_MULTILABEL); 2981 MNT_FLAG(MNT_ACLS); 2982 MNT_FLAG(MNT_NOATIME); 2983 MNT_FLAG(MNT_NOCLUSTERR); 2984 MNT_FLAG(MNT_NOCLUSTERW); 2985 MNT_FLAG(MNT_NFS4ACLS); 2986 MNT_FLAG(MNT_EXRDONLY); 2987 MNT_FLAG(MNT_EXPORTED); 2988 MNT_FLAG(MNT_DEFEXPORTED); 2989 MNT_FLAG(MNT_EXPORTANON); 2990 MNT_FLAG(MNT_EXKERB); 2991 MNT_FLAG(MNT_EXPUBLIC); 2992 MNT_FLAG(MNT_LOCAL); 2993 MNT_FLAG(MNT_QUOTA); 2994 MNT_FLAG(MNT_ROOTFS); 2995 MNT_FLAG(MNT_USER); 2996 MNT_FLAG(MNT_IGNORE); 2997 MNT_FLAG(MNT_UPDATE); 2998 MNT_FLAG(MNT_DELEXPORT); 2999 MNT_FLAG(MNT_RELOAD); 3000 MNT_FLAG(MNT_FORCE); 3001 MNT_FLAG(MNT_SNAPSHOT); 3002 MNT_FLAG(MNT_BYFSID); 3003 #undef MNT_FLAG 3004 if (mflags != 0) { 3005 if (buf[0] != '\0') 3006 strlcat(buf, ", ", sizeof(buf)); 3007 snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf), 3008 "0x%016jx", mflags); 3009 } 3010 db_printf(" mnt_flag = %s\n", buf); 3011 3012 buf[0] = '\0'; 3013 flags = mp->mnt_kern_flag; 3014 #define MNT_KERN_FLAG(flag) do { \ 3015 if (flags & (flag)) { \ 3016 if (buf[0] != '\0') \ 3017 strlcat(buf, ", ", sizeof(buf)); \ 3018 strlcat(buf, (#flag) + 5, sizeof(buf)); \ 3019 flags &= ~(flag); \ 3020 } \ 3021 } while (0) 3022 MNT_KERN_FLAG(MNTK_UNMOUNTF); 3023 MNT_KERN_FLAG(MNTK_ASYNC); 3024 MNT_KERN_FLAG(MNTK_SOFTDEP); 3025 MNT_KERN_FLAG(MNTK_NOINSMNTQ); 3026 MNT_KERN_FLAG(MNTK_DRAINING); 3027 MNT_KERN_FLAG(MNTK_REFEXPIRE); 3028 MNT_KERN_FLAG(MNTK_EXTENDED_SHARED); 3029 MNT_KERN_FLAG(MNTK_SHARED_WRITES); 3030 MNT_KERN_FLAG(MNTK_NOASYNC); 3031 MNT_KERN_FLAG(MNTK_UNMOUNT); 3032 MNT_KERN_FLAG(MNTK_MWAIT); 3033 MNT_KERN_FLAG(MNTK_SUSPEND); 3034 MNT_KERN_FLAG(MNTK_SUSPEND2); 3035 MNT_KERN_FLAG(MNTK_SUSPENDED); 3036 MNT_KERN_FLAG(MNTK_MPSAFE); 3037 MNT_KERN_FLAG(MNTK_LOOKUP_SHARED); 3038 MNT_KERN_FLAG(MNTK_NOKNOTE); 3039 #undef MNT_KERN_FLAG 3040 if (flags != 0) { 3041 if (buf[0] != '\0') 3042 strlcat(buf, ", ", sizeof(buf)); 3043 snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf), 3044 "0x%08x", flags); 3045 } 3046 db_printf(" mnt_kern_flag = %s\n", buf); 3047 3048 db_printf(" mnt_opt = "); 3049 opt = TAILQ_FIRST(mp->mnt_opt); 3050 if (opt != NULL) { 3051 db_printf("%s", opt->name); 3052 opt = TAILQ_NEXT(opt, link); 3053 while (opt != NULL) { 3054 db_printf(", %s", opt->name); 3055 opt = TAILQ_NEXT(opt, link); 3056 } 3057 } 3058 db_printf("\n"); 3059 3060 sp = &mp->mnt_stat; 3061 db_printf(" mnt_stat = { version=%u type=%u flags=0x%016jx " 3062 "bsize=%ju iosize=%ju blocks=%ju bfree=%ju bavail=%jd files=%ju " 3063 "ffree=%jd syncwrites=%ju asyncwrites=%ju syncreads=%ju " 3064 "asyncreads=%ju namemax=%u owner=%u fsid=[%d, %d] }\n", 3065 (u_int)sp->f_version, (u_int)sp->f_type, (uintmax_t)sp->f_flags, 3066 (uintmax_t)sp->f_bsize, (uintmax_t)sp->f_iosize, 3067 (uintmax_t)sp->f_blocks, (uintmax_t)sp->f_bfree, 3068 (intmax_t)sp->f_bavail, (uintmax_t)sp->f_files, 3069 (intmax_t)sp->f_ffree, (uintmax_t)sp->f_syncwrites, 3070 (uintmax_t)sp->f_asyncwrites, (uintmax_t)sp->f_syncreads, 3071 (uintmax_t)sp->f_asyncreads, (u_int)sp->f_namemax, 3072 (u_int)sp->f_owner, (int)sp->f_fsid.val[0], (int)sp->f_fsid.val[1]); 3073 3074 db_printf(" mnt_cred = { uid=%u ruid=%u", 3075 (u_int)mp->mnt_cred->cr_uid, (u_int)mp->mnt_cred->cr_ruid); 3076 if (jailed(mp->mnt_cred)) 3077 db_printf(", jail=%d", mp->mnt_cred->cr_prison->pr_id); 3078 db_printf(" }\n"); 3079 db_printf(" mnt_ref = %d\n", mp->mnt_ref); 3080 db_printf(" mnt_gen = %d\n", mp->mnt_gen); 3081 db_printf(" mnt_nvnodelistsize = %d\n", mp->mnt_nvnodelistsize); 3082 db_printf(" mnt_activevnodelistsize = %d\n", 3083 mp->mnt_activevnodelistsize); 3084 db_printf(" mnt_writeopcount = %d\n", mp->mnt_writeopcount); 3085 db_printf(" mnt_maxsymlinklen = %d\n", mp->mnt_maxsymlinklen); 3086 db_printf(" mnt_iosize_max = %d\n", mp->mnt_iosize_max); 3087 db_printf(" mnt_hashseed = %u\n", mp->mnt_hashseed); 3088 db_printf(" mnt_secondary_writes = %d\n", mp->mnt_secondary_writes); 3089 db_printf(" mnt_secondary_accwrites = %d\n", 3090 mp->mnt_secondary_accwrites); 3091 db_printf(" mnt_gjprovider = %s\n", 3092 mp->mnt_gjprovider != NULL ? mp->mnt_gjprovider : "NULL"); 3093 3094 db_printf("\n\nList of active vnodes\n"); 3095 TAILQ_FOREACH(vp, &mp->mnt_activevnodelist, v_actfreelist) { 3096 if (vp->v_type != VMARKER) { 3097 vn_printf(vp, "vnode "); 3098 if (db_pager_quit) 3099 break; 3100 } 3101 } 3102 db_printf("\n\nList of inactive vnodes\n"); 3103 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) { 3104 if (vp->v_type != VMARKER && (vp->v_iflag & VI_ACTIVE) == 0) { 3105 vn_printf(vp, "vnode "); 3106 if (db_pager_quit) 3107 break; 3108 } 3109 } 3110 } 3111 #endif /* DDB */ 3112 3113 /* 3114 * Fill in a struct xvfsconf based on a struct vfsconf. 3115 */ 3116 static void 3117 vfsconf2x(struct vfsconf *vfsp, struct xvfsconf *xvfsp) 3118 { 3119 3120 strcpy(xvfsp->vfc_name, vfsp->vfc_name); 3121 xvfsp->vfc_typenum = vfsp->vfc_typenum; 3122 xvfsp->vfc_refcount = vfsp->vfc_refcount; 3123 xvfsp->vfc_flags = vfsp->vfc_flags; 3124 /* 3125 * These are unused in userland, we keep them 3126 * to not break binary compatibility. 3127 */ 3128 xvfsp->vfc_vfsops = NULL; 3129 xvfsp->vfc_next = NULL; 3130 } 3131 3132 /* 3133 * Top level filesystem related information gathering. 3134 */ 3135 static int 3136 sysctl_vfs_conflist(SYSCTL_HANDLER_ARGS) 3137 { 3138 struct vfsconf *vfsp; 3139 struct xvfsconf xvfsp; 3140 int error; 3141 3142 error = 0; 3143 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) { 3144 bzero(&xvfsp, sizeof(xvfsp)); 3145 vfsconf2x(vfsp, &xvfsp); 3146 error = SYSCTL_OUT(req, &xvfsp, sizeof xvfsp); 3147 if (error) 3148 break; 3149 } 3150 return (error); 3151 } 3152 3153 SYSCTL_PROC(_vfs, OID_AUTO, conflist, CTLTYPE_OPAQUE | CTLFLAG_RD, 3154 NULL, 0, sysctl_vfs_conflist, 3155 "S,xvfsconf", "List of all configured filesystems"); 3156 3157 #ifndef BURN_BRIDGES 3158 static int sysctl_ovfs_conf(SYSCTL_HANDLER_ARGS); 3159 3160 static int 3161 vfs_sysctl(SYSCTL_HANDLER_ARGS) 3162 { 3163 int *name = (int *)arg1 - 1; /* XXX */ 3164 u_int namelen = arg2 + 1; /* XXX */ 3165 struct vfsconf *vfsp; 3166 struct xvfsconf xvfsp; 3167 3168 log(LOG_WARNING, "userland calling deprecated sysctl, " 3169 "please rebuild world\n"); 3170 3171 #if 1 || defined(COMPAT_PRELITE2) 3172 /* Resolve ambiguity between VFS_VFSCONF and VFS_GENERIC. */ 3173 if (namelen == 1) 3174 return (sysctl_ovfs_conf(oidp, arg1, arg2, req)); 3175 #endif 3176 3177 switch (name[1]) { 3178 case VFS_MAXTYPENUM: 3179 if (namelen != 2) 3180 return (ENOTDIR); 3181 return (SYSCTL_OUT(req, &maxvfsconf, sizeof(int))); 3182 case VFS_CONF: 3183 if (namelen != 3) 3184 return (ENOTDIR); /* overloaded */ 3185 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) 3186 if (vfsp->vfc_typenum == name[2]) 3187 break; 3188 if (vfsp == NULL) 3189 return (EOPNOTSUPP); 3190 bzero(&xvfsp, sizeof(xvfsp)); 3191 vfsconf2x(vfsp, &xvfsp); 3192 return (SYSCTL_OUT(req, &xvfsp, sizeof(xvfsp))); 3193 } 3194 return (EOPNOTSUPP); 3195 } 3196 3197 static SYSCTL_NODE(_vfs, VFS_GENERIC, generic, CTLFLAG_RD | CTLFLAG_SKIP, 3198 vfs_sysctl, "Generic filesystem"); 3199 3200 #if 1 || defined(COMPAT_PRELITE2) 3201 3202 static int 3203 sysctl_ovfs_conf(SYSCTL_HANDLER_ARGS) 3204 { 3205 int error; 3206 struct vfsconf *vfsp; 3207 struct ovfsconf ovfs; 3208 3209 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) { 3210 bzero(&ovfs, sizeof(ovfs)); 3211 ovfs.vfc_vfsops = vfsp->vfc_vfsops; /* XXX used as flag */ 3212 strcpy(ovfs.vfc_name, vfsp->vfc_name); 3213 ovfs.vfc_index = vfsp->vfc_typenum; 3214 ovfs.vfc_refcount = vfsp->vfc_refcount; 3215 ovfs.vfc_flags = vfsp->vfc_flags; 3216 error = SYSCTL_OUT(req, &ovfs, sizeof ovfs); 3217 if (error) 3218 return error; 3219 } 3220 return 0; 3221 } 3222 3223 #endif /* 1 || COMPAT_PRELITE2 */ 3224 #endif /* !BURN_BRIDGES */ 3225 3226 #define KINFO_VNODESLOP 10 3227 #ifdef notyet 3228 /* 3229 * Dump vnode list (via sysctl). 3230 */ 3231 /* ARGSUSED */ 3232 static int 3233 sysctl_vnode(SYSCTL_HANDLER_ARGS) 3234 { 3235 struct xvnode *xvn; 3236 struct mount *mp; 3237 struct vnode *vp; 3238 int error, len, n; 3239 3240 /* 3241 * Stale numvnodes access is not fatal here. 3242 */ 3243 req->lock = 0; 3244 len = (numvnodes + KINFO_VNODESLOP) * sizeof *xvn; 3245 if (!req->oldptr) 3246 /* Make an estimate */ 3247 return (SYSCTL_OUT(req, 0, len)); 3248 3249 error = sysctl_wire_old_buffer(req, 0); 3250 if (error != 0) 3251 return (error); 3252 xvn = malloc(len, M_TEMP, M_ZERO | M_WAITOK); 3253 n = 0; 3254 mtx_lock(&mountlist_mtx); 3255 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 3256 if (vfs_busy(mp, MBF_NOWAIT | MBF_MNTLSTLOCK)) 3257 continue; 3258 MNT_ILOCK(mp); 3259 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) { 3260 if (n == len) 3261 break; 3262 vref(vp); 3263 xvn[n].xv_size = sizeof *xvn; 3264 xvn[n].xv_vnode = vp; 3265 xvn[n].xv_id = 0; /* XXX compat */ 3266 #define XV_COPY(field) xvn[n].xv_##field = vp->v_##field 3267 XV_COPY(usecount); 3268 XV_COPY(writecount); 3269 XV_COPY(holdcnt); 3270 XV_COPY(mount); 3271 XV_COPY(numoutput); 3272 XV_COPY(type); 3273 #undef XV_COPY 3274 xvn[n].xv_flag = vp->v_vflag; 3275 3276 switch (vp->v_type) { 3277 case VREG: 3278 case VDIR: 3279 case VLNK: 3280 break; 3281 case VBLK: 3282 case VCHR: 3283 if (vp->v_rdev == NULL) { 3284 vrele(vp); 3285 continue; 3286 } 3287 xvn[n].xv_dev = dev2udev(vp->v_rdev); 3288 break; 3289 case VSOCK: 3290 xvn[n].xv_socket = vp->v_socket; 3291 break; 3292 case VFIFO: 3293 xvn[n].xv_fifo = vp->v_fifoinfo; 3294 break; 3295 case VNON: 3296 case VBAD: 3297 default: 3298 /* shouldn't happen? */ 3299 vrele(vp); 3300 continue; 3301 } 3302 vrele(vp); 3303 ++n; 3304 } 3305 MNT_IUNLOCK(mp); 3306 mtx_lock(&mountlist_mtx); 3307 vfs_unbusy(mp); 3308 if (n == len) 3309 break; 3310 } 3311 mtx_unlock(&mountlist_mtx); 3312 3313 error = SYSCTL_OUT(req, xvn, n * sizeof *xvn); 3314 free(xvn, M_TEMP); 3315 return (error); 3316 } 3317 3318 SYSCTL_PROC(_kern, KERN_VNODE, vnode, CTLTYPE_OPAQUE|CTLFLAG_RD, 3319 0, 0, sysctl_vnode, "S,xvnode", ""); 3320 #endif 3321 3322 /* 3323 * Unmount all filesystems. The list is traversed in reverse order 3324 * of mounting to avoid dependencies. 3325 */ 3326 void 3327 vfs_unmountall(void) 3328 { 3329 struct mount *mp; 3330 struct thread *td; 3331 int error; 3332 3333 KASSERT(curthread != NULL, ("vfs_unmountall: NULL curthread")); 3334 CTR1(KTR_VFS, "%s: unmounting all filesystems", __func__); 3335 td = curthread; 3336 3337 /* 3338 * Since this only runs when rebooting, it is not interlocked. 3339 */ 3340 while(!TAILQ_EMPTY(&mountlist)) { 3341 mp = TAILQ_LAST(&mountlist, mntlist); 3342 error = dounmount(mp, MNT_FORCE, td); 3343 if (error) { 3344 TAILQ_REMOVE(&mountlist, mp, mnt_list); 3345 /* 3346 * XXX: Due to the way in which we mount the root 3347 * file system off of devfs, devfs will generate a 3348 * "busy" warning when we try to unmount it before 3349 * the root. Don't print a warning as a result in 3350 * order to avoid false positive errors that may 3351 * cause needless upset. 3352 */ 3353 if (strcmp(mp->mnt_vfc->vfc_name, "devfs") != 0) { 3354 printf("unmount of %s failed (", 3355 mp->mnt_stat.f_mntonname); 3356 if (error == EBUSY) 3357 printf("BUSY)\n"); 3358 else 3359 printf("%d)\n", error); 3360 } 3361 } else { 3362 /* The unmount has removed mp from the mountlist */ 3363 } 3364 } 3365 } 3366 3367 /* 3368 * perform msync on all vnodes under a mount point 3369 * the mount point must be locked. 3370 */ 3371 void 3372 vfs_msync(struct mount *mp, int flags) 3373 { 3374 struct vnode *vp, *mvp; 3375 struct vm_object *obj; 3376 3377 CTR2(KTR_VFS, "%s: mp %p", __func__, mp); 3378 MNT_VNODE_FOREACH_ACTIVE(vp, mp, mvp) { 3379 obj = vp->v_object; 3380 if (obj != NULL && (obj->flags & OBJ_MIGHTBEDIRTY) != 0 && 3381 (flags == MNT_WAIT || VOP_ISLOCKED(vp) == 0)) { 3382 if (!vget(vp, 3383 LK_EXCLUSIVE | LK_RETRY | LK_INTERLOCK, 3384 curthread)) { 3385 if (vp->v_vflag & VV_NOSYNC) { /* unlinked */ 3386 vput(vp); 3387 continue; 3388 } 3389 3390 obj = vp->v_object; 3391 if (obj != NULL) { 3392 VM_OBJECT_LOCK(obj); 3393 vm_object_page_clean(obj, 0, 0, 3394 flags == MNT_WAIT ? 3395 OBJPC_SYNC : OBJPC_NOSYNC); 3396 VM_OBJECT_UNLOCK(obj); 3397 } 3398 vput(vp); 3399 } 3400 } else 3401 VI_UNLOCK(vp); 3402 } 3403 } 3404 3405 static void 3406 destroy_vpollinfo(struct vpollinfo *vi) 3407 { 3408 seldrain(&vi->vpi_selinfo); 3409 knlist_destroy(&vi->vpi_selinfo.si_note); 3410 mtx_destroy(&vi->vpi_lock); 3411 uma_zfree(vnodepoll_zone, vi); 3412 } 3413 3414 /* 3415 * Initalize per-vnode helper structure to hold poll-related state. 3416 */ 3417 void 3418 v_addpollinfo(struct vnode *vp) 3419 { 3420 struct vpollinfo *vi; 3421 3422 if (vp->v_pollinfo != NULL) 3423 return; 3424 vi = uma_zalloc(vnodepoll_zone, M_WAITOK); 3425 mtx_init(&vi->vpi_lock, "vnode pollinfo", NULL, MTX_DEF); 3426 knlist_init(&vi->vpi_selinfo.si_note, vp, vfs_knllock, 3427 vfs_knlunlock, vfs_knl_assert_locked, vfs_knl_assert_unlocked); 3428 VI_LOCK(vp); 3429 if (vp->v_pollinfo != NULL) { 3430 VI_UNLOCK(vp); 3431 destroy_vpollinfo(vi); 3432 return; 3433 } 3434 vp->v_pollinfo = vi; 3435 VI_UNLOCK(vp); 3436 } 3437 3438 /* 3439 * Record a process's interest in events which might happen to 3440 * a vnode. Because poll uses the historic select-style interface 3441 * internally, this routine serves as both the ``check for any 3442 * pending events'' and the ``record my interest in future events'' 3443 * functions. (These are done together, while the lock is held, 3444 * to avoid race conditions.) 3445 */ 3446 int 3447 vn_pollrecord(struct vnode *vp, struct thread *td, int events) 3448 { 3449 3450 v_addpollinfo(vp); 3451 mtx_lock(&vp->v_pollinfo->vpi_lock); 3452 if (vp->v_pollinfo->vpi_revents & events) { 3453 /* 3454 * This leaves events we are not interested 3455 * in available for the other process which 3456 * which presumably had requested them 3457 * (otherwise they would never have been 3458 * recorded). 3459 */ 3460 events &= vp->v_pollinfo->vpi_revents; 3461 vp->v_pollinfo->vpi_revents &= ~events; 3462 3463 mtx_unlock(&vp->v_pollinfo->vpi_lock); 3464 return (events); 3465 } 3466 vp->v_pollinfo->vpi_events |= events; 3467 selrecord(td, &vp->v_pollinfo->vpi_selinfo); 3468 mtx_unlock(&vp->v_pollinfo->vpi_lock); 3469 return (0); 3470 } 3471 3472 /* 3473 * Routine to create and manage a filesystem syncer vnode. 3474 */ 3475 #define sync_close ((int (*)(struct vop_close_args *))nullop) 3476 static int sync_fsync(struct vop_fsync_args *); 3477 static int sync_inactive(struct vop_inactive_args *); 3478 static int sync_reclaim(struct vop_reclaim_args *); 3479 3480 static struct vop_vector sync_vnodeops = { 3481 .vop_bypass = VOP_EOPNOTSUPP, 3482 .vop_close = sync_close, /* close */ 3483 .vop_fsync = sync_fsync, /* fsync */ 3484 .vop_inactive = sync_inactive, /* inactive */ 3485 .vop_reclaim = sync_reclaim, /* reclaim */ 3486 .vop_lock1 = vop_stdlock, /* lock */ 3487 .vop_unlock = vop_stdunlock, /* unlock */ 3488 .vop_islocked = vop_stdislocked, /* islocked */ 3489 }; 3490 3491 /* 3492 * Create a new filesystem syncer vnode for the specified mount point. 3493 */ 3494 void 3495 vfs_allocate_syncvnode(struct mount *mp) 3496 { 3497 struct vnode *vp; 3498 struct bufobj *bo; 3499 static long start, incr, next; 3500 int error; 3501 3502 /* Allocate a new vnode */ 3503 error = getnewvnode("syncer", mp, &sync_vnodeops, &vp); 3504 if (error != 0) 3505 panic("vfs_allocate_syncvnode: getnewvnode() failed"); 3506 vp->v_type = VNON; 3507 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 3508 vp->v_vflag |= VV_FORCEINSMQ; 3509 error = insmntque(vp, mp); 3510 if (error != 0) 3511 panic("vfs_allocate_syncvnode: insmntque() failed"); 3512 vp->v_vflag &= ~VV_FORCEINSMQ; 3513 VOP_UNLOCK(vp, 0); 3514 /* 3515 * Place the vnode onto the syncer worklist. We attempt to 3516 * scatter them about on the list so that they will go off 3517 * at evenly distributed times even if all the filesystems 3518 * are mounted at once. 3519 */ 3520 next += incr; 3521 if (next == 0 || next > syncer_maxdelay) { 3522 start /= 2; 3523 incr /= 2; 3524 if (start == 0) { 3525 start = syncer_maxdelay / 2; 3526 incr = syncer_maxdelay; 3527 } 3528 next = start; 3529 } 3530 bo = &vp->v_bufobj; 3531 BO_LOCK(bo); 3532 vn_syncer_add_to_worklist(bo, syncdelay > 0 ? next % syncdelay : 0); 3533 /* XXX - vn_syncer_add_to_worklist() also grabs and drops sync_mtx. */ 3534 mtx_lock(&sync_mtx); 3535 sync_vnode_count++; 3536 if (mp->mnt_syncer == NULL) { 3537 mp->mnt_syncer = vp; 3538 vp = NULL; 3539 } 3540 mtx_unlock(&sync_mtx); 3541 BO_UNLOCK(bo); 3542 if (vp != NULL) { 3543 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 3544 vgone(vp); 3545 vput(vp); 3546 } 3547 } 3548 3549 void 3550 vfs_deallocate_syncvnode(struct mount *mp) 3551 { 3552 struct vnode *vp; 3553 3554 mtx_lock(&sync_mtx); 3555 vp = mp->mnt_syncer; 3556 if (vp != NULL) 3557 mp->mnt_syncer = NULL; 3558 mtx_unlock(&sync_mtx); 3559 if (vp != NULL) 3560 vrele(vp); 3561 } 3562 3563 /* 3564 * Do a lazy sync of the filesystem. 3565 */ 3566 static int 3567 sync_fsync(struct vop_fsync_args *ap) 3568 { 3569 struct vnode *syncvp = ap->a_vp; 3570 struct mount *mp = syncvp->v_mount; 3571 int error, save; 3572 struct bufobj *bo; 3573 3574 /* 3575 * We only need to do something if this is a lazy evaluation. 3576 */ 3577 if (ap->a_waitfor != MNT_LAZY) 3578 return (0); 3579 3580 /* 3581 * Move ourselves to the back of the sync list. 3582 */ 3583 bo = &syncvp->v_bufobj; 3584 BO_LOCK(bo); 3585 vn_syncer_add_to_worklist(bo, syncdelay); 3586 BO_UNLOCK(bo); 3587 3588 /* 3589 * Walk the list of vnodes pushing all that are dirty and 3590 * not already on the sync list. 3591 */ 3592 mtx_lock(&mountlist_mtx); 3593 if (vfs_busy(mp, MBF_NOWAIT | MBF_MNTLSTLOCK) != 0) { 3594 mtx_unlock(&mountlist_mtx); 3595 return (0); 3596 } 3597 if (vn_start_write(NULL, &mp, V_NOWAIT) != 0) { 3598 vfs_unbusy(mp); 3599 return (0); 3600 } 3601 save = curthread_pflags_set(TDP_SYNCIO); 3602 vfs_msync(mp, MNT_NOWAIT); 3603 error = VFS_SYNC(mp, MNT_LAZY); 3604 curthread_pflags_restore(save); 3605 vn_finished_write(mp); 3606 vfs_unbusy(mp); 3607 return (error); 3608 } 3609 3610 /* 3611 * The syncer vnode is no referenced. 3612 */ 3613 static int 3614 sync_inactive(struct vop_inactive_args *ap) 3615 { 3616 3617 vgone(ap->a_vp); 3618 return (0); 3619 } 3620 3621 /* 3622 * The syncer vnode is no longer needed and is being decommissioned. 3623 * 3624 * Modifications to the worklist must be protected by sync_mtx. 3625 */ 3626 static int 3627 sync_reclaim(struct vop_reclaim_args *ap) 3628 { 3629 struct vnode *vp = ap->a_vp; 3630 struct bufobj *bo; 3631 3632 bo = &vp->v_bufobj; 3633 BO_LOCK(bo); 3634 mtx_lock(&sync_mtx); 3635 if (vp->v_mount->mnt_syncer == vp) 3636 vp->v_mount->mnt_syncer = NULL; 3637 if (bo->bo_flag & BO_ONWORKLST) { 3638 LIST_REMOVE(bo, bo_synclist); 3639 syncer_worklist_len--; 3640 sync_vnode_count--; 3641 bo->bo_flag &= ~BO_ONWORKLST; 3642 } 3643 mtx_unlock(&sync_mtx); 3644 BO_UNLOCK(bo); 3645 3646 return (0); 3647 } 3648 3649 /* 3650 * Check if vnode represents a disk device 3651 */ 3652 int 3653 vn_isdisk(struct vnode *vp, int *errp) 3654 { 3655 int error; 3656 3657 error = 0; 3658 dev_lock(); 3659 if (vp->v_type != VCHR) 3660 error = ENOTBLK; 3661 else if (vp->v_rdev == NULL) 3662 error = ENXIO; 3663 else if (vp->v_rdev->si_devsw == NULL) 3664 error = ENXIO; 3665 else if (!(vp->v_rdev->si_devsw->d_flags & D_DISK)) 3666 error = ENOTBLK; 3667 dev_unlock(); 3668 if (errp != NULL) 3669 *errp = error; 3670 return (error == 0); 3671 } 3672 3673 /* 3674 * Common filesystem object access control check routine. Accepts a 3675 * vnode's type, "mode", uid and gid, requested access mode, credentials, 3676 * and optional call-by-reference privused argument allowing vaccess() 3677 * to indicate to the caller whether privilege was used to satisfy the 3678 * request (obsoleted). Returns 0 on success, or an errno on failure. 3679 */ 3680 int 3681 vaccess(enum vtype type, mode_t file_mode, uid_t file_uid, gid_t file_gid, 3682 accmode_t accmode, struct ucred *cred, int *privused) 3683 { 3684 accmode_t dac_granted; 3685 accmode_t priv_granted; 3686 3687 KASSERT((accmode & ~(VEXEC | VWRITE | VREAD | VADMIN | VAPPEND)) == 0, 3688 ("invalid bit in accmode")); 3689 KASSERT((accmode & VAPPEND) == 0 || (accmode & VWRITE), 3690 ("VAPPEND without VWRITE")); 3691 3692 /* 3693 * Look for a normal, non-privileged way to access the file/directory 3694 * as requested. If it exists, go with that. 3695 */ 3696 3697 if (privused != NULL) 3698 *privused = 0; 3699 3700 dac_granted = 0; 3701 3702 /* Check the owner. */ 3703 if (cred->cr_uid == file_uid) { 3704 dac_granted |= VADMIN; 3705 if (file_mode & S_IXUSR) 3706 dac_granted |= VEXEC; 3707 if (file_mode & S_IRUSR) 3708 dac_granted |= VREAD; 3709 if (file_mode & S_IWUSR) 3710 dac_granted |= (VWRITE | VAPPEND); 3711 3712 if ((accmode & dac_granted) == accmode) 3713 return (0); 3714 3715 goto privcheck; 3716 } 3717 3718 /* Otherwise, check the groups (first match) */ 3719 if (groupmember(file_gid, cred)) { 3720 if (file_mode & S_IXGRP) 3721 dac_granted |= VEXEC; 3722 if (file_mode & S_IRGRP) 3723 dac_granted |= VREAD; 3724 if (file_mode & S_IWGRP) 3725 dac_granted |= (VWRITE | VAPPEND); 3726 3727 if ((accmode & dac_granted) == accmode) 3728 return (0); 3729 3730 goto privcheck; 3731 } 3732 3733 /* Otherwise, check everyone else. */ 3734 if (file_mode & S_IXOTH) 3735 dac_granted |= VEXEC; 3736 if (file_mode & S_IROTH) 3737 dac_granted |= VREAD; 3738 if (file_mode & S_IWOTH) 3739 dac_granted |= (VWRITE | VAPPEND); 3740 if ((accmode & dac_granted) == accmode) 3741 return (0); 3742 3743 privcheck: 3744 /* 3745 * Build a privilege mask to determine if the set of privileges 3746 * satisfies the requirements when combined with the granted mask 3747 * from above. For each privilege, if the privilege is required, 3748 * bitwise or the request type onto the priv_granted mask. 3749 */ 3750 priv_granted = 0; 3751 3752 if (type == VDIR) { 3753 /* 3754 * For directories, use PRIV_VFS_LOOKUP to satisfy VEXEC 3755 * requests, instead of PRIV_VFS_EXEC. 3756 */ 3757 if ((accmode & VEXEC) && ((dac_granted & VEXEC) == 0) && 3758 !priv_check_cred(cred, PRIV_VFS_LOOKUP, 0)) 3759 priv_granted |= VEXEC; 3760 } else { 3761 /* 3762 * Ensure that at least one execute bit is on. Otherwise, 3763 * a privileged user will always succeed, and we don't want 3764 * this to happen unless the file really is executable. 3765 */ 3766 if ((accmode & VEXEC) && ((dac_granted & VEXEC) == 0) && 3767 (file_mode & (S_IXUSR | S_IXGRP | S_IXOTH)) != 0 && 3768 !priv_check_cred(cred, PRIV_VFS_EXEC, 0)) 3769 priv_granted |= VEXEC; 3770 } 3771 3772 if ((accmode & VREAD) && ((dac_granted & VREAD) == 0) && 3773 !priv_check_cred(cred, PRIV_VFS_READ, 0)) 3774 priv_granted |= VREAD; 3775 3776 if ((accmode & VWRITE) && ((dac_granted & VWRITE) == 0) && 3777 !priv_check_cred(cred, PRIV_VFS_WRITE, 0)) 3778 priv_granted |= (VWRITE | VAPPEND); 3779 3780 if ((accmode & VADMIN) && ((dac_granted & VADMIN) == 0) && 3781 !priv_check_cred(cred, PRIV_VFS_ADMIN, 0)) 3782 priv_granted |= VADMIN; 3783 3784 if ((accmode & (priv_granted | dac_granted)) == accmode) { 3785 /* XXX audit: privilege used */ 3786 if (privused != NULL) 3787 *privused = 1; 3788 return (0); 3789 } 3790 3791 return ((accmode & VADMIN) ? EPERM : EACCES); 3792 } 3793 3794 /* 3795 * Credential check based on process requesting service, and per-attribute 3796 * permissions. 3797 */ 3798 int 3799 extattr_check_cred(struct vnode *vp, int attrnamespace, struct ucred *cred, 3800 struct thread *td, accmode_t accmode) 3801 { 3802 3803 /* 3804 * Kernel-invoked always succeeds. 3805 */ 3806 if (cred == NOCRED) 3807 return (0); 3808 3809 /* 3810 * Do not allow privileged processes in jail to directly manipulate 3811 * system attributes. 3812 */ 3813 switch (attrnamespace) { 3814 case EXTATTR_NAMESPACE_SYSTEM: 3815 /* Potentially should be: return (EPERM); */ 3816 return (priv_check_cred(cred, PRIV_VFS_EXTATTR_SYSTEM, 0)); 3817 case EXTATTR_NAMESPACE_USER: 3818 return (VOP_ACCESS(vp, accmode, cred, td)); 3819 default: 3820 return (EPERM); 3821 } 3822 } 3823 3824 #ifdef DEBUG_VFS_LOCKS 3825 /* 3826 * This only exists to supress warnings from unlocked specfs accesses. It is 3827 * no longer ok to have an unlocked VFS. 3828 */ 3829 #define IGNORE_LOCK(vp) (panicstr != NULL || (vp) == NULL || \ 3830 (vp)->v_type == VCHR || (vp)->v_type == VBAD) 3831 3832 int vfs_badlock_ddb = 1; /* Drop into debugger on violation. */ 3833 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_ddb, CTLFLAG_RW, &vfs_badlock_ddb, 0, 3834 "Drop into debugger on lock violation"); 3835 3836 int vfs_badlock_mutex = 1; /* Check for interlock across VOPs. */ 3837 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_mutex, CTLFLAG_RW, &vfs_badlock_mutex, 3838 0, "Check for interlock across VOPs"); 3839 3840 int vfs_badlock_print = 1; /* Print lock violations. */ 3841 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_print, CTLFLAG_RW, &vfs_badlock_print, 3842 0, "Print lock violations"); 3843 3844 #ifdef KDB 3845 int vfs_badlock_backtrace = 1; /* Print backtrace at lock violations. */ 3846 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_backtrace, CTLFLAG_RW, 3847 &vfs_badlock_backtrace, 0, "Print backtrace at lock violations"); 3848 #endif 3849 3850 static void 3851 vfs_badlock(const char *msg, const char *str, struct vnode *vp) 3852 { 3853 3854 #ifdef KDB 3855 if (vfs_badlock_backtrace) 3856 kdb_backtrace(); 3857 #endif 3858 if (vfs_badlock_print) 3859 printf("%s: %p %s\n", str, (void *)vp, msg); 3860 if (vfs_badlock_ddb) 3861 kdb_enter(KDB_WHY_VFSLOCK, "lock violation"); 3862 } 3863 3864 void 3865 assert_vi_locked(struct vnode *vp, const char *str) 3866 { 3867 3868 if (vfs_badlock_mutex && !mtx_owned(VI_MTX(vp))) 3869 vfs_badlock("interlock is not locked but should be", str, vp); 3870 } 3871 3872 void 3873 assert_vi_unlocked(struct vnode *vp, const char *str) 3874 { 3875 3876 if (vfs_badlock_mutex && mtx_owned(VI_MTX(vp))) 3877 vfs_badlock("interlock is locked but should not be", str, vp); 3878 } 3879 3880 void 3881 assert_vop_locked(struct vnode *vp, const char *str) 3882 { 3883 3884 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) == 0) 3885 vfs_badlock("is not locked but should be", str, vp); 3886 } 3887 3888 void 3889 assert_vop_unlocked(struct vnode *vp, const char *str) 3890 { 3891 3892 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) == LK_EXCLUSIVE) 3893 vfs_badlock("is locked but should not be", str, vp); 3894 } 3895 3896 void 3897 assert_vop_elocked(struct vnode *vp, const char *str) 3898 { 3899 3900 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) != LK_EXCLUSIVE) 3901 vfs_badlock("is not exclusive locked but should be", str, vp); 3902 } 3903 3904 #if 0 3905 void 3906 assert_vop_elocked_other(struct vnode *vp, const char *str) 3907 { 3908 3909 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) != LK_EXCLOTHER) 3910 vfs_badlock("is not exclusive locked by another thread", 3911 str, vp); 3912 } 3913 3914 void 3915 assert_vop_slocked(struct vnode *vp, const char *str) 3916 { 3917 3918 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) != LK_SHARED) 3919 vfs_badlock("is not locked shared but should be", str, vp); 3920 } 3921 #endif /* 0 */ 3922 #endif /* DEBUG_VFS_LOCKS */ 3923 3924 void 3925 vop_rename_fail(struct vop_rename_args *ap) 3926 { 3927 3928 if (ap->a_tvp != NULL) 3929 vput(ap->a_tvp); 3930 if (ap->a_tdvp == ap->a_tvp) 3931 vrele(ap->a_tdvp); 3932 else 3933 vput(ap->a_tdvp); 3934 vrele(ap->a_fdvp); 3935 vrele(ap->a_fvp); 3936 } 3937 3938 void 3939 vop_rename_pre(void *ap) 3940 { 3941 struct vop_rename_args *a = ap; 3942 3943 #ifdef DEBUG_VFS_LOCKS 3944 if (a->a_tvp) 3945 ASSERT_VI_UNLOCKED(a->a_tvp, "VOP_RENAME"); 3946 ASSERT_VI_UNLOCKED(a->a_tdvp, "VOP_RENAME"); 3947 ASSERT_VI_UNLOCKED(a->a_fvp, "VOP_RENAME"); 3948 ASSERT_VI_UNLOCKED(a->a_fdvp, "VOP_RENAME"); 3949 3950 /* Check the source (from). */ 3951 if (a->a_tdvp->v_vnlock != a->a_fdvp->v_vnlock && 3952 (a->a_tvp == NULL || a->a_tvp->v_vnlock != a->a_fdvp->v_vnlock)) 3953 ASSERT_VOP_UNLOCKED(a->a_fdvp, "vop_rename: fdvp locked"); 3954 if (a->a_tvp == NULL || a->a_tvp->v_vnlock != a->a_fvp->v_vnlock) 3955 ASSERT_VOP_UNLOCKED(a->a_fvp, "vop_rename: fvp locked"); 3956 3957 /* Check the target. */ 3958 if (a->a_tvp) 3959 ASSERT_VOP_LOCKED(a->a_tvp, "vop_rename: tvp not locked"); 3960 ASSERT_VOP_LOCKED(a->a_tdvp, "vop_rename: tdvp not locked"); 3961 #endif 3962 if (a->a_tdvp != a->a_fdvp) 3963 vhold(a->a_fdvp); 3964 if (a->a_tvp != a->a_fvp) 3965 vhold(a->a_fvp); 3966 vhold(a->a_tdvp); 3967 if (a->a_tvp) 3968 vhold(a->a_tvp); 3969 } 3970 3971 void 3972 vop_strategy_pre(void *ap) 3973 { 3974 #ifdef DEBUG_VFS_LOCKS 3975 struct vop_strategy_args *a; 3976 struct buf *bp; 3977 3978 a = ap; 3979 bp = a->a_bp; 3980 3981 /* 3982 * Cluster ops lock their component buffers but not the IO container. 3983 */ 3984 if ((bp->b_flags & B_CLUSTER) != 0) 3985 return; 3986 3987 if (panicstr == NULL && !BUF_ISLOCKED(bp)) { 3988 if (vfs_badlock_print) 3989 printf( 3990 "VOP_STRATEGY: bp is not locked but should be\n"); 3991 if (vfs_badlock_ddb) 3992 kdb_enter(KDB_WHY_VFSLOCK, "lock violation"); 3993 } 3994 #endif 3995 } 3996 3997 void 3998 vop_lookup_pre(void *ap) 3999 { 4000 #ifdef DEBUG_VFS_LOCKS 4001 struct vop_lookup_args *a; 4002 struct vnode *dvp; 4003 4004 a = ap; 4005 dvp = a->a_dvp; 4006 ASSERT_VI_UNLOCKED(dvp, "VOP_LOOKUP"); 4007 ASSERT_VOP_LOCKED(dvp, "VOP_LOOKUP"); 4008 #endif 4009 } 4010 4011 void 4012 vop_lookup_post(void *ap, int rc) 4013 { 4014 #ifdef DEBUG_VFS_LOCKS 4015 struct vop_lookup_args *a; 4016 struct vnode *dvp; 4017 struct vnode *vp; 4018 4019 a = ap; 4020 dvp = a->a_dvp; 4021 vp = *(a->a_vpp); 4022 4023 ASSERT_VI_UNLOCKED(dvp, "VOP_LOOKUP"); 4024 ASSERT_VOP_LOCKED(dvp, "VOP_LOOKUP"); 4025 4026 if (!rc) 4027 ASSERT_VOP_LOCKED(vp, "VOP_LOOKUP (child)"); 4028 #endif 4029 } 4030 4031 void 4032 vop_lock_pre(void *ap) 4033 { 4034 #ifdef DEBUG_VFS_LOCKS 4035 struct vop_lock1_args *a = ap; 4036 4037 if ((a->a_flags & LK_INTERLOCK) == 0) 4038 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_LOCK"); 4039 else 4040 ASSERT_VI_LOCKED(a->a_vp, "VOP_LOCK"); 4041 #endif 4042 } 4043 4044 void 4045 vop_lock_post(void *ap, int rc) 4046 { 4047 #ifdef DEBUG_VFS_LOCKS 4048 struct vop_lock1_args *a = ap; 4049 4050 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_LOCK"); 4051 if (rc == 0) 4052 ASSERT_VOP_LOCKED(a->a_vp, "VOP_LOCK"); 4053 #endif 4054 } 4055 4056 void 4057 vop_unlock_pre(void *ap) 4058 { 4059 #ifdef DEBUG_VFS_LOCKS 4060 struct vop_unlock_args *a = ap; 4061 4062 if (a->a_flags & LK_INTERLOCK) 4063 ASSERT_VI_LOCKED(a->a_vp, "VOP_UNLOCK"); 4064 ASSERT_VOP_LOCKED(a->a_vp, "VOP_UNLOCK"); 4065 #endif 4066 } 4067 4068 void 4069 vop_unlock_post(void *ap, int rc) 4070 { 4071 #ifdef DEBUG_VFS_LOCKS 4072 struct vop_unlock_args *a = ap; 4073 4074 if (a->a_flags & LK_INTERLOCK) 4075 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_UNLOCK"); 4076 #endif 4077 } 4078 4079 void 4080 vop_create_post(void *ap, int rc) 4081 { 4082 struct vop_create_args *a = ap; 4083 4084 if (!rc) 4085 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 4086 } 4087 4088 void 4089 vop_deleteextattr_post(void *ap, int rc) 4090 { 4091 struct vop_deleteextattr_args *a = ap; 4092 4093 if (!rc) 4094 VFS_KNOTE_LOCKED(a->a_vp, NOTE_ATTRIB); 4095 } 4096 4097 void 4098 vop_link_post(void *ap, int rc) 4099 { 4100 struct vop_link_args *a = ap; 4101 4102 if (!rc) { 4103 VFS_KNOTE_LOCKED(a->a_vp, NOTE_LINK); 4104 VFS_KNOTE_LOCKED(a->a_tdvp, NOTE_WRITE); 4105 } 4106 } 4107 4108 void 4109 vop_mkdir_post(void *ap, int rc) 4110 { 4111 struct vop_mkdir_args *a = ap; 4112 4113 if (!rc) 4114 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE | NOTE_LINK); 4115 } 4116 4117 void 4118 vop_mknod_post(void *ap, int rc) 4119 { 4120 struct vop_mknod_args *a = ap; 4121 4122 if (!rc) 4123 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 4124 } 4125 4126 void 4127 vop_remove_post(void *ap, int rc) 4128 { 4129 struct vop_remove_args *a = ap; 4130 4131 if (!rc) { 4132 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 4133 VFS_KNOTE_LOCKED(a->a_vp, NOTE_DELETE); 4134 } 4135 } 4136 4137 void 4138 vop_rename_post(void *ap, int rc) 4139 { 4140 struct vop_rename_args *a = ap; 4141 4142 if (!rc) { 4143 VFS_KNOTE_UNLOCKED(a->a_fdvp, NOTE_WRITE); 4144 VFS_KNOTE_UNLOCKED(a->a_tdvp, NOTE_WRITE); 4145 VFS_KNOTE_UNLOCKED(a->a_fvp, NOTE_RENAME); 4146 if (a->a_tvp) 4147 VFS_KNOTE_UNLOCKED(a->a_tvp, NOTE_DELETE); 4148 } 4149 if (a->a_tdvp != a->a_fdvp) 4150 vdrop(a->a_fdvp); 4151 if (a->a_tvp != a->a_fvp) 4152 vdrop(a->a_fvp); 4153 vdrop(a->a_tdvp); 4154 if (a->a_tvp) 4155 vdrop(a->a_tvp); 4156 } 4157 4158 void 4159 vop_rmdir_post(void *ap, int rc) 4160 { 4161 struct vop_rmdir_args *a = ap; 4162 4163 if (!rc) { 4164 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE | NOTE_LINK); 4165 VFS_KNOTE_LOCKED(a->a_vp, NOTE_DELETE); 4166 } 4167 } 4168 4169 void 4170 vop_setattr_post(void *ap, int rc) 4171 { 4172 struct vop_setattr_args *a = ap; 4173 4174 if (!rc) 4175 VFS_KNOTE_LOCKED(a->a_vp, NOTE_ATTRIB); 4176 } 4177 4178 void 4179 vop_setextattr_post(void *ap, int rc) 4180 { 4181 struct vop_setextattr_args *a = ap; 4182 4183 if (!rc) 4184 VFS_KNOTE_LOCKED(a->a_vp, NOTE_ATTRIB); 4185 } 4186 4187 void 4188 vop_symlink_post(void *ap, int rc) 4189 { 4190 struct vop_symlink_args *a = ap; 4191 4192 if (!rc) 4193 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 4194 } 4195 4196 static struct knlist fs_knlist; 4197 4198 static void 4199 vfs_event_init(void *arg) 4200 { 4201 knlist_init_mtx(&fs_knlist, NULL); 4202 } 4203 /* XXX - correct order? */ 4204 SYSINIT(vfs_knlist, SI_SUB_VFS, SI_ORDER_ANY, vfs_event_init, NULL); 4205 4206 void 4207 vfs_event_signal(fsid_t *fsid, uint32_t event, intptr_t data __unused) 4208 { 4209 4210 KNOTE_UNLOCKED(&fs_knlist, event); 4211 } 4212 4213 static int filt_fsattach(struct knote *kn); 4214 static void filt_fsdetach(struct knote *kn); 4215 static int filt_fsevent(struct knote *kn, long hint); 4216 4217 struct filterops fs_filtops = { 4218 .f_isfd = 0, 4219 .f_attach = filt_fsattach, 4220 .f_detach = filt_fsdetach, 4221 .f_event = filt_fsevent 4222 }; 4223 4224 static int 4225 filt_fsattach(struct knote *kn) 4226 { 4227 4228 kn->kn_flags |= EV_CLEAR; 4229 knlist_add(&fs_knlist, kn, 0); 4230 return (0); 4231 } 4232 4233 static void 4234 filt_fsdetach(struct knote *kn) 4235 { 4236 4237 knlist_remove(&fs_knlist, kn, 0); 4238 } 4239 4240 static int 4241 filt_fsevent(struct knote *kn, long hint) 4242 { 4243 4244 kn->kn_fflags |= hint; 4245 return (kn->kn_fflags != 0); 4246 } 4247 4248 static int 4249 sysctl_vfs_ctl(SYSCTL_HANDLER_ARGS) 4250 { 4251 struct vfsidctl vc; 4252 int error; 4253 struct mount *mp; 4254 4255 error = SYSCTL_IN(req, &vc, sizeof(vc)); 4256 if (error) 4257 return (error); 4258 if (vc.vc_vers != VFS_CTL_VERS1) 4259 return (EINVAL); 4260 mp = vfs_getvfs(&vc.vc_fsid); 4261 if (mp == NULL) 4262 return (ENOENT); 4263 /* ensure that a specific sysctl goes to the right filesystem. */ 4264 if (strcmp(vc.vc_fstypename, "*") != 0 && 4265 strcmp(vc.vc_fstypename, mp->mnt_vfc->vfc_name) != 0) { 4266 vfs_rel(mp); 4267 return (EINVAL); 4268 } 4269 VCTLTOREQ(&vc, req); 4270 error = VFS_SYSCTL(mp, vc.vc_op, req); 4271 vfs_rel(mp); 4272 return (error); 4273 } 4274 4275 SYSCTL_PROC(_vfs, OID_AUTO, ctl, CTLTYPE_OPAQUE | CTLFLAG_WR, 4276 NULL, 0, sysctl_vfs_ctl, "", 4277 "Sysctl by fsid"); 4278 4279 /* 4280 * Function to initialize a va_filerev field sensibly. 4281 * XXX: Wouldn't a random number make a lot more sense ?? 4282 */ 4283 u_quad_t 4284 init_va_filerev(void) 4285 { 4286 struct bintime bt; 4287 4288 getbinuptime(&bt); 4289 return (((u_quad_t)bt.sec << 32LL) | (bt.frac >> 32LL)); 4290 } 4291 4292 static int filt_vfsread(struct knote *kn, long hint); 4293 static int filt_vfswrite(struct knote *kn, long hint); 4294 static int filt_vfsvnode(struct knote *kn, long hint); 4295 static void filt_vfsdetach(struct knote *kn); 4296 static struct filterops vfsread_filtops = { 4297 .f_isfd = 1, 4298 .f_detach = filt_vfsdetach, 4299 .f_event = filt_vfsread 4300 }; 4301 static struct filterops vfswrite_filtops = { 4302 .f_isfd = 1, 4303 .f_detach = filt_vfsdetach, 4304 .f_event = filt_vfswrite 4305 }; 4306 static struct filterops vfsvnode_filtops = { 4307 .f_isfd = 1, 4308 .f_detach = filt_vfsdetach, 4309 .f_event = filt_vfsvnode 4310 }; 4311 4312 static void 4313 vfs_knllock(void *arg) 4314 { 4315 struct vnode *vp = arg; 4316 4317 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 4318 } 4319 4320 static void 4321 vfs_knlunlock(void *arg) 4322 { 4323 struct vnode *vp = arg; 4324 4325 VOP_UNLOCK(vp, 0); 4326 } 4327 4328 static void 4329 vfs_knl_assert_locked(void *arg) 4330 { 4331 #ifdef DEBUG_VFS_LOCKS 4332 struct vnode *vp = arg; 4333 4334 ASSERT_VOP_LOCKED(vp, "vfs_knl_assert_locked"); 4335 #endif 4336 } 4337 4338 static void 4339 vfs_knl_assert_unlocked(void *arg) 4340 { 4341 #ifdef DEBUG_VFS_LOCKS 4342 struct vnode *vp = arg; 4343 4344 ASSERT_VOP_UNLOCKED(vp, "vfs_knl_assert_unlocked"); 4345 #endif 4346 } 4347 4348 int 4349 vfs_kqfilter(struct vop_kqfilter_args *ap) 4350 { 4351 struct vnode *vp = ap->a_vp; 4352 struct knote *kn = ap->a_kn; 4353 struct knlist *knl; 4354 4355 switch (kn->kn_filter) { 4356 case EVFILT_READ: 4357 kn->kn_fop = &vfsread_filtops; 4358 break; 4359 case EVFILT_WRITE: 4360 kn->kn_fop = &vfswrite_filtops; 4361 break; 4362 case EVFILT_VNODE: 4363 kn->kn_fop = &vfsvnode_filtops; 4364 break; 4365 default: 4366 return (EINVAL); 4367 } 4368 4369 kn->kn_hook = (caddr_t)vp; 4370 4371 v_addpollinfo(vp); 4372 if (vp->v_pollinfo == NULL) 4373 return (ENOMEM); 4374 knl = &vp->v_pollinfo->vpi_selinfo.si_note; 4375 knlist_add(knl, kn, 0); 4376 4377 return (0); 4378 } 4379 4380 /* 4381 * Detach knote from vnode 4382 */ 4383 static void 4384 filt_vfsdetach(struct knote *kn) 4385 { 4386 struct vnode *vp = (struct vnode *)kn->kn_hook; 4387 4388 KASSERT(vp->v_pollinfo != NULL, ("Missing v_pollinfo")); 4389 knlist_remove(&vp->v_pollinfo->vpi_selinfo.si_note, kn, 0); 4390 } 4391 4392 /*ARGSUSED*/ 4393 static int 4394 filt_vfsread(struct knote *kn, long hint) 4395 { 4396 struct vnode *vp = (struct vnode *)kn->kn_hook; 4397 struct vattr va; 4398 int res; 4399 4400 /* 4401 * filesystem is gone, so set the EOF flag and schedule 4402 * the knote for deletion. 4403 */ 4404 if (hint == NOTE_REVOKE) { 4405 VI_LOCK(vp); 4406 kn->kn_flags |= (EV_EOF | EV_ONESHOT); 4407 VI_UNLOCK(vp); 4408 return (1); 4409 } 4410 4411 if (VOP_GETATTR(vp, &va, curthread->td_ucred)) 4412 return (0); 4413 4414 VI_LOCK(vp); 4415 kn->kn_data = va.va_size - kn->kn_fp->f_offset; 4416 res = (kn->kn_data != 0); 4417 VI_UNLOCK(vp); 4418 return (res); 4419 } 4420 4421 /*ARGSUSED*/ 4422 static int 4423 filt_vfswrite(struct knote *kn, long hint) 4424 { 4425 struct vnode *vp = (struct vnode *)kn->kn_hook; 4426 4427 VI_LOCK(vp); 4428 4429 /* 4430 * filesystem is gone, so set the EOF flag and schedule 4431 * the knote for deletion. 4432 */ 4433 if (hint == NOTE_REVOKE) 4434 kn->kn_flags |= (EV_EOF | EV_ONESHOT); 4435 4436 kn->kn_data = 0; 4437 VI_UNLOCK(vp); 4438 return (1); 4439 } 4440 4441 static int 4442 filt_vfsvnode(struct knote *kn, long hint) 4443 { 4444 struct vnode *vp = (struct vnode *)kn->kn_hook; 4445 int res; 4446 4447 VI_LOCK(vp); 4448 if (kn->kn_sfflags & hint) 4449 kn->kn_fflags |= hint; 4450 if (hint == NOTE_REVOKE) { 4451 kn->kn_flags |= EV_EOF; 4452 VI_UNLOCK(vp); 4453 return (1); 4454 } 4455 res = (kn->kn_fflags != 0); 4456 VI_UNLOCK(vp); 4457 return (res); 4458 } 4459 4460 int 4461 vfs_read_dirent(struct vop_readdir_args *ap, struct dirent *dp, off_t off) 4462 { 4463 int error; 4464 4465 if (dp->d_reclen > ap->a_uio->uio_resid) 4466 return (ENAMETOOLONG); 4467 error = uiomove(dp, dp->d_reclen, ap->a_uio); 4468 if (error) { 4469 if (ap->a_ncookies != NULL) { 4470 if (ap->a_cookies != NULL) 4471 free(ap->a_cookies, M_TEMP); 4472 ap->a_cookies = NULL; 4473 *ap->a_ncookies = 0; 4474 } 4475 return (error); 4476 } 4477 if (ap->a_ncookies == NULL) 4478 return (0); 4479 4480 KASSERT(ap->a_cookies, 4481 ("NULL ap->a_cookies value with non-NULL ap->a_ncookies!")); 4482 4483 *ap->a_cookies = realloc(*ap->a_cookies, 4484 (*ap->a_ncookies + 1) * sizeof(u_long), M_TEMP, M_WAITOK | M_ZERO); 4485 (*ap->a_cookies)[*ap->a_ncookies] = off; 4486 return (0); 4487 } 4488 4489 /* 4490 * Mark for update the access time of the file if the filesystem 4491 * supports VOP_MARKATIME. This functionality is used by execve and 4492 * mmap, so we want to avoid the I/O implied by directly setting 4493 * va_atime for the sake of efficiency. 4494 */ 4495 void 4496 vfs_mark_atime(struct vnode *vp, struct ucred *cred) 4497 { 4498 struct mount *mp; 4499 4500 mp = vp->v_mount; 4501 VFS_ASSERT_GIANT(mp); 4502 ASSERT_VOP_LOCKED(vp, "vfs_mark_atime"); 4503 if (mp != NULL && (mp->mnt_flag & (MNT_NOATIME | MNT_RDONLY)) == 0) 4504 (void)VOP_MARKATIME(vp); 4505 } 4506 4507 /* 4508 * The purpose of this routine is to remove granularity from accmode_t, 4509 * reducing it into standard unix access bits - VEXEC, VREAD, VWRITE, 4510 * VADMIN and VAPPEND. 4511 * 4512 * If it returns 0, the caller is supposed to continue with the usual 4513 * access checks using 'accmode' as modified by this routine. If it 4514 * returns nonzero value, the caller is supposed to return that value 4515 * as errno. 4516 * 4517 * Note that after this routine runs, accmode may be zero. 4518 */ 4519 int 4520 vfs_unixify_accmode(accmode_t *accmode) 4521 { 4522 /* 4523 * There is no way to specify explicit "deny" rule using 4524 * file mode or POSIX.1e ACLs. 4525 */ 4526 if (*accmode & VEXPLICIT_DENY) { 4527 *accmode = 0; 4528 return (0); 4529 } 4530 4531 /* 4532 * None of these can be translated into usual access bits. 4533 * Also, the common case for NFSv4 ACLs is to not contain 4534 * either of these bits. Caller should check for VWRITE 4535 * on the containing directory instead. 4536 */ 4537 if (*accmode & (VDELETE_CHILD | VDELETE)) 4538 return (EPERM); 4539 4540 if (*accmode & VADMIN_PERMS) { 4541 *accmode &= ~VADMIN_PERMS; 4542 *accmode |= VADMIN; 4543 } 4544 4545 /* 4546 * There is no way to deny VREAD_ATTRIBUTES, VREAD_ACL 4547 * or VSYNCHRONIZE using file mode or POSIX.1e ACL. 4548 */ 4549 *accmode &= ~(VSTAT_PERMS | VSYNCHRONIZE); 4550 4551 return (0); 4552 } 4553 4554 /* 4555 * These are helper functions for filesystems to traverse all 4556 * their vnodes. See MNT_VNODE_FOREACH_ALL() in sys/mount.h. 4557 * 4558 * This interface replaces MNT_VNODE_FOREACH. 4559 */ 4560 4561 MALLOC_DEFINE(M_VNODE_MARKER, "vnodemarker", "vnode marker"); 4562 4563 struct vnode * 4564 __mnt_vnode_next_all(struct vnode **mvp, struct mount *mp) 4565 { 4566 struct vnode *vp; 4567 4568 if (should_yield()) 4569 kern_yield(PRI_UNCHANGED); 4570 MNT_ILOCK(mp); 4571 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch")); 4572 vp = TAILQ_NEXT(*mvp, v_nmntvnodes); 4573 while (vp != NULL && (vp->v_type == VMARKER || 4574 (vp->v_iflag & VI_DOOMED) != 0)) 4575 vp = TAILQ_NEXT(vp, v_nmntvnodes); 4576 4577 /* Check if we are done */ 4578 if (vp == NULL) { 4579 __mnt_vnode_markerfree_all(mvp, mp); 4580 /* MNT_IUNLOCK(mp); -- done in above function */ 4581 mtx_assert(MNT_MTX(mp), MA_NOTOWNED); 4582 return (NULL); 4583 } 4584 TAILQ_REMOVE(&mp->mnt_nvnodelist, *mvp, v_nmntvnodes); 4585 TAILQ_INSERT_AFTER(&mp->mnt_nvnodelist, vp, *mvp, v_nmntvnodes); 4586 VI_LOCK(vp); 4587 MNT_IUNLOCK(mp); 4588 return (vp); 4589 } 4590 4591 struct vnode * 4592 __mnt_vnode_first_all(struct vnode **mvp, struct mount *mp) 4593 { 4594 struct vnode *vp; 4595 4596 *mvp = malloc(sizeof(struct vnode), M_VNODE_MARKER, M_WAITOK | M_ZERO); 4597 MNT_ILOCK(mp); 4598 MNT_REF(mp); 4599 (*mvp)->v_type = VMARKER; 4600 4601 vp = TAILQ_FIRST(&mp->mnt_nvnodelist); 4602 while (vp != NULL && (vp->v_type == VMARKER || 4603 (vp->v_iflag & VI_DOOMED) != 0)) 4604 vp = TAILQ_NEXT(vp, v_nmntvnodes); 4605 4606 /* Check if we are done */ 4607 if (vp == NULL) { 4608 MNT_REL(mp); 4609 MNT_IUNLOCK(mp); 4610 free(*mvp, M_VNODE_MARKER); 4611 *mvp = NULL; 4612 return (NULL); 4613 } 4614 (*mvp)->v_mount = mp; 4615 TAILQ_INSERT_AFTER(&mp->mnt_nvnodelist, vp, *mvp, v_nmntvnodes); 4616 VI_LOCK(vp); 4617 MNT_IUNLOCK(mp); 4618 return (vp); 4619 } 4620 4621 4622 void 4623 __mnt_vnode_markerfree_all(struct vnode **mvp, struct mount *mp) 4624 { 4625 4626 if (*mvp == NULL) { 4627 MNT_IUNLOCK(mp); 4628 return; 4629 } 4630 4631 mtx_assert(MNT_MTX(mp), MA_OWNED); 4632 4633 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch")); 4634 TAILQ_REMOVE(&mp->mnt_nvnodelist, *mvp, v_nmntvnodes); 4635 MNT_REL(mp); 4636 MNT_IUNLOCK(mp); 4637 free(*mvp, M_VNODE_MARKER); 4638 *mvp = NULL; 4639 } 4640 4641 /* 4642 * These are helper functions for filesystems to traverse their 4643 * active vnodes. See MNT_VNODE_FOREACH_ACTIVE() in sys/mount.h 4644 */ 4645 struct vnode * 4646 __mnt_vnode_next_active(struct vnode **mvp, struct mount *mp) 4647 { 4648 struct vnode *vp, *nvp; 4649 4650 if (should_yield()) 4651 kern_yield(PRI_UNCHANGED); 4652 MNT_ILOCK(mp); 4653 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch")); 4654 vp = TAILQ_NEXT(*mvp, v_actfreelist); 4655 while (vp != NULL) { 4656 VI_LOCK(vp); 4657 if (vp->v_mount == mp && vp->v_type != VMARKER && 4658 (vp->v_iflag & VI_DOOMED) == 0) 4659 break; 4660 nvp = TAILQ_NEXT(vp, v_actfreelist); 4661 VI_UNLOCK(vp); 4662 vp = nvp; 4663 } 4664 4665 /* Check if we are done */ 4666 if (vp == NULL) { 4667 __mnt_vnode_markerfree_active(mvp, mp); 4668 /* MNT_IUNLOCK(mp); -- done in above function */ 4669 mtx_assert(MNT_MTX(mp), MA_NOTOWNED); 4670 return (NULL); 4671 } 4672 mtx_lock(&vnode_free_list_mtx); 4673 TAILQ_REMOVE(&mp->mnt_activevnodelist, *mvp, v_actfreelist); 4674 TAILQ_INSERT_AFTER(&mp->mnt_activevnodelist, vp, *mvp, v_actfreelist); 4675 mtx_unlock(&vnode_free_list_mtx); 4676 MNT_IUNLOCK(mp); 4677 return (vp); 4678 } 4679 4680 struct vnode * 4681 __mnt_vnode_first_active(struct vnode **mvp, struct mount *mp) 4682 { 4683 struct vnode *vp, *nvp; 4684 4685 *mvp = malloc(sizeof(struct vnode), M_VNODE_MARKER, M_WAITOK | M_ZERO); 4686 MNT_ILOCK(mp); 4687 MNT_REF(mp); 4688 (*mvp)->v_type = VMARKER; 4689 4690 vp = TAILQ_NEXT(*mvp, v_actfreelist); 4691 while (vp != NULL) { 4692 VI_LOCK(vp); 4693 if (vp->v_mount == mp && vp->v_type != VMARKER && 4694 (vp->v_iflag & VI_DOOMED) == 0) 4695 break; 4696 nvp = TAILQ_NEXT(vp, v_actfreelist); 4697 VI_UNLOCK(vp); 4698 vp = nvp; 4699 } 4700 4701 /* Check if we are done */ 4702 if (vp == NULL) { 4703 MNT_REL(mp); 4704 MNT_IUNLOCK(mp); 4705 free(*mvp, M_VNODE_MARKER); 4706 *mvp = NULL; 4707 return (NULL); 4708 } 4709 (*mvp)->v_mount = mp; 4710 mtx_lock(&vnode_free_list_mtx); 4711 TAILQ_INSERT_AFTER(&mp->mnt_activevnodelist, vp, *mvp, v_actfreelist); 4712 mtx_unlock(&vnode_free_list_mtx); 4713 MNT_IUNLOCK(mp); 4714 return (vp); 4715 } 4716 4717 void 4718 __mnt_vnode_markerfree_active(struct vnode **mvp, struct mount *mp) 4719 { 4720 4721 if (*mvp == NULL) { 4722 MNT_IUNLOCK(mp); 4723 return; 4724 } 4725 4726 mtx_assert(MNT_MTX(mp), MA_OWNED); 4727 4728 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch")); 4729 mtx_lock(&vnode_free_list_mtx); 4730 TAILQ_REMOVE(&mp->mnt_activevnodelist, *mvp, v_actfreelist); 4731 mtx_unlock(&vnode_free_list_mtx); 4732 MNT_REL(mp); 4733 MNT_IUNLOCK(mp); 4734 free(*mvp, M_VNODE_MARKER); 4735 *mvp = NULL; 4736 } 4737