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_compat.h" 45 #include "opt_ddb.h" 46 #include "opt_watchdog.h" 47 48 #include <sys/param.h> 49 #include <sys/systm.h> 50 #include <sys/bio.h> 51 #include <sys/buf.h> 52 #include <sys/condvar.h> 53 #include <sys/conf.h> 54 #include <sys/dirent.h> 55 #include <sys/event.h> 56 #include <sys/eventhandler.h> 57 #include <sys/extattr.h> 58 #include <sys/file.h> 59 #include <sys/fcntl.h> 60 #include <sys/jail.h> 61 #include <sys/kdb.h> 62 #include <sys/kernel.h> 63 #include <sys/kthread.h> 64 #include <sys/lockf.h> 65 #include <sys/malloc.h> 66 #include <sys/mount.h> 67 #include <sys/namei.h> 68 #include <sys/priv.h> 69 #include <sys/reboot.h> 70 #include <sys/rwlock.h> 71 #include <sys/sched.h> 72 #include <sys/sleepqueue.h> 73 #include <sys/smp.h> 74 #include <sys/stat.h> 75 #include <sys/sysctl.h> 76 #include <sys/syslog.h> 77 #include <sys/vmmeter.h> 78 #include <sys/vnode.h> 79 #include <sys/watchdog.h> 80 81 #include <machine/stdarg.h> 82 83 #include <security/mac/mac_framework.h> 84 85 #include <vm/vm.h> 86 #include <vm/vm_object.h> 87 #include <vm/vm_extern.h> 88 #include <vm/pmap.h> 89 #include <vm/vm_map.h> 90 #include <vm/vm_page.h> 91 #include <vm/vm_kern.h> 92 #include <vm/uma.h> 93 94 #ifdef DDB 95 #include <ddb/ddb.h> 96 #endif 97 98 static void delmntque(struct vnode *vp); 99 static int flushbuflist(struct bufv *bufv, int flags, struct bufobj *bo, 100 int slpflag, int slptimeo); 101 static void syncer_shutdown(void *arg, int howto); 102 static int vtryrecycle(struct vnode *vp); 103 static void v_incr_usecount(struct vnode *); 104 static void v_decr_usecount(struct vnode *); 105 static void v_decr_useonly(struct vnode *); 106 static void v_upgrade_usecount(struct vnode *); 107 static void vnlru_free(int); 108 static void vgonel(struct vnode *); 109 static void vfs_knllock(void *arg); 110 static void vfs_knlunlock(void *arg); 111 static void vfs_knl_assert_locked(void *arg); 112 static void vfs_knl_assert_unlocked(void *arg); 113 static void destroy_vpollinfo(struct vpollinfo *vi); 114 115 /* 116 * Number of vnodes in existence. Increased whenever getnewvnode() 117 * allocates a new vnode, decreased in vdropl() for VI_DOOMED vnode. 118 */ 119 static unsigned long numvnodes; 120 121 SYSCTL_ULONG(_vfs, OID_AUTO, numvnodes, CTLFLAG_RD, &numvnodes, 0, 122 "Number of vnodes in existence"); 123 124 /* 125 * Conversion tables for conversion from vnode types to inode formats 126 * and back. 127 */ 128 enum vtype iftovt_tab[16] = { 129 VNON, VFIFO, VCHR, VNON, VDIR, VNON, VBLK, VNON, 130 VREG, VNON, VLNK, VNON, VSOCK, VNON, VNON, VBAD, 131 }; 132 int vttoif_tab[10] = { 133 0, S_IFREG, S_IFDIR, S_IFBLK, S_IFCHR, S_IFLNK, 134 S_IFSOCK, S_IFIFO, S_IFMT, S_IFMT 135 }; 136 137 /* 138 * List of vnodes that are ready for recycling. 139 */ 140 static TAILQ_HEAD(freelst, vnode) vnode_free_list; 141 142 /* 143 * Free vnode target. Free vnodes may simply be files which have been stat'd 144 * but not read. This is somewhat common, and a small cache of such files 145 * should be kept to avoid recreation costs. 146 */ 147 static u_long wantfreevnodes; 148 SYSCTL_ULONG(_vfs, OID_AUTO, wantfreevnodes, CTLFLAG_RW, &wantfreevnodes, 0, ""); 149 /* Number of vnodes in the free list. */ 150 static u_long freevnodes; 151 SYSCTL_ULONG(_vfs, OID_AUTO, freevnodes, CTLFLAG_RD, &freevnodes, 0, 152 "Number of vnodes in the free list"); 153 154 static int vlru_allow_cache_src; 155 SYSCTL_INT(_vfs, OID_AUTO, vlru_allow_cache_src, CTLFLAG_RW, 156 &vlru_allow_cache_src, 0, "Allow vlru to reclaim source vnode"); 157 158 /* 159 * Various variables used for debugging the new implementation of 160 * reassignbuf(). 161 * XXX these are probably of (very) limited utility now. 162 */ 163 static int reassignbufcalls; 164 SYSCTL_INT(_vfs, OID_AUTO, reassignbufcalls, CTLFLAG_RW, &reassignbufcalls, 0, 165 "Number of calls to reassignbuf"); 166 167 /* 168 * Cache for the mount type id assigned to NFS. This is used for 169 * special checks in nfs/nfs_nqlease.c and vm/vnode_pager.c. 170 */ 171 int nfs_mount_type = -1; 172 173 /* To keep more than one thread at a time from running vfs_getnewfsid */ 174 static struct mtx mntid_mtx; 175 176 /* 177 * Lock for any access to the following: 178 * vnode_free_list 179 * numvnodes 180 * freevnodes 181 */ 182 static struct mtx vnode_free_list_mtx; 183 184 /* Publicly exported FS */ 185 struct nfs_public nfs_pub; 186 187 /* Zone for allocation of new vnodes - used exclusively by getnewvnode() */ 188 static uma_zone_t vnode_zone; 189 static uma_zone_t vnodepoll_zone; 190 191 /* 192 * The workitem queue. 193 * 194 * It is useful to delay writes of file data and filesystem metadata 195 * for tens of seconds so that quickly created and deleted files need 196 * not waste disk bandwidth being created and removed. To realize this, 197 * we append vnodes to a "workitem" queue. When running with a soft 198 * updates implementation, most pending metadata dependencies should 199 * not wait for more than a few seconds. Thus, mounted on block devices 200 * are delayed only about a half the time that file data is delayed. 201 * Similarly, directory updates are more critical, so are only delayed 202 * about a third the time that file data is delayed. Thus, there are 203 * SYNCER_MAXDELAY queues that are processed round-robin at a rate of 204 * one each second (driven off the filesystem syncer process). The 205 * syncer_delayno variable indicates the next queue that is to be processed. 206 * Items that need to be processed soon are placed in this queue: 207 * 208 * syncer_workitem_pending[syncer_delayno] 209 * 210 * A delay of fifteen seconds is done by placing the request fifteen 211 * entries later in the queue: 212 * 213 * syncer_workitem_pending[(syncer_delayno + 15) & syncer_mask] 214 * 215 */ 216 static int syncer_delayno; 217 static long syncer_mask; 218 LIST_HEAD(synclist, bufobj); 219 static struct synclist *syncer_workitem_pending; 220 /* 221 * The sync_mtx protects: 222 * bo->bo_synclist 223 * sync_vnode_count 224 * syncer_delayno 225 * syncer_state 226 * syncer_workitem_pending 227 * syncer_worklist_len 228 * rushjob 229 */ 230 static struct mtx sync_mtx; 231 static struct cv sync_wakeup; 232 233 #define SYNCER_MAXDELAY 32 234 static int syncer_maxdelay = SYNCER_MAXDELAY; /* maximum delay time */ 235 static int syncdelay = 30; /* max time to delay syncing data */ 236 static int filedelay = 30; /* time to delay syncing files */ 237 SYSCTL_INT(_kern, OID_AUTO, filedelay, CTLFLAG_RW, &filedelay, 0, 238 "Time to delay syncing files (in seconds)"); 239 static int dirdelay = 29; /* time to delay syncing directories */ 240 SYSCTL_INT(_kern, OID_AUTO, dirdelay, CTLFLAG_RW, &dirdelay, 0, 241 "Time to delay syncing directories (in seconds)"); 242 static int metadelay = 28; /* time to delay syncing metadata */ 243 SYSCTL_INT(_kern, OID_AUTO, metadelay, CTLFLAG_RW, &metadelay, 0, 244 "Time to delay syncing metadata (in seconds)"); 245 static int rushjob; /* number of slots to run ASAP */ 246 static int stat_rush_requests; /* number of times I/O speeded up */ 247 SYSCTL_INT(_debug, OID_AUTO, rush_requests, CTLFLAG_RW, &stat_rush_requests, 0, 248 "Number of times I/O speeded up (rush requests)"); 249 250 /* 251 * When shutting down the syncer, run it at four times normal speed. 252 */ 253 #define SYNCER_SHUTDOWN_SPEEDUP 4 254 static int sync_vnode_count; 255 static int syncer_worklist_len; 256 static enum { SYNCER_RUNNING, SYNCER_SHUTTING_DOWN, SYNCER_FINAL_DELAY } 257 syncer_state; 258 259 /* 260 * Number of vnodes we want to exist at any one time. This is mostly used 261 * to size hash tables in vnode-related code. It is normally not used in 262 * getnewvnode(), as wantfreevnodes is normally nonzero.) 263 * 264 * XXX desiredvnodes is historical cruft and should not exist. 265 */ 266 int desiredvnodes; 267 SYSCTL_INT(_kern, KERN_MAXVNODES, maxvnodes, CTLFLAG_RW, 268 &desiredvnodes, 0, "Maximum number of vnodes"); 269 SYSCTL_ULONG(_kern, OID_AUTO, minvnodes, CTLFLAG_RW, 270 &wantfreevnodes, 0, "Minimum number of vnodes (legacy)"); 271 static int vnlru_nowhere; 272 SYSCTL_INT(_debug, OID_AUTO, vnlru_nowhere, CTLFLAG_RW, 273 &vnlru_nowhere, 0, "Number of times the vnlru process ran without success"); 274 275 /* 276 * Macros to control when a vnode is freed and recycled. All require 277 * the vnode interlock. 278 */ 279 #define VCANRECYCLE(vp) (((vp)->v_iflag & VI_FREE) && !(vp)->v_holdcnt) 280 #define VSHOULDFREE(vp) (!((vp)->v_iflag & VI_FREE) && !(vp)->v_holdcnt) 281 #define VSHOULDBUSY(vp) (((vp)->v_iflag & VI_FREE) && (vp)->v_holdcnt) 282 283 /* Shift count for (uintptr_t)vp to initialize vp->v_hash. */ 284 static int vnsz2log; 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 u_int i; 300 int physvnodes, virtvnodes; 301 302 /* 303 * Desiredvnodes is a function of the physical memory size and the 304 * kernel's heap size. Generally speaking, it scales with the 305 * physical memory size. The ratio of desiredvnodes to physical pages 306 * is one to four until desiredvnodes exceeds 98,304. Thereafter, the 307 * marginal ratio of desiredvnodes to physical pages is one to 308 * sixteen. However, desiredvnodes is limited by the kernel's heap 309 * size. The memory required by desiredvnodes vnodes and vm objects 310 * may not exceed one seventh of the kernel's heap size. 311 */ 312 physvnodes = maxproc + cnt.v_page_count / 16 + 3 * min(98304 * 4, 313 cnt.v_page_count) / 16; 314 virtvnodes = vm_kmem_size / (7 * (sizeof(struct vm_object) + 315 sizeof(struct vnode))); 316 desiredvnodes = min(physvnodes, virtvnodes); 317 if (desiredvnodes > MAXVNODES_MAX) { 318 if (bootverbose) 319 printf("Reducing kern.maxvnodes %d -> %d\n", 320 desiredvnodes, MAXVNODES_MAX); 321 desiredvnodes = MAXVNODES_MAX; 322 } 323 wantfreevnodes = desiredvnodes / 4; 324 mtx_init(&mntid_mtx, "mntid", NULL, MTX_DEF); 325 TAILQ_INIT(&vnode_free_list); 326 mtx_init(&vnode_free_list_mtx, "vnode_free_list", NULL, MTX_DEF); 327 vnode_zone = uma_zcreate("VNODE", sizeof (struct vnode), NULL, NULL, 328 NULL, NULL, UMA_ALIGN_PTR, 0); 329 vnodepoll_zone = uma_zcreate("VNODEPOLL", sizeof (struct vpollinfo), 330 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); 331 /* 332 * Initialize the filesystem syncer. 333 */ 334 syncer_workitem_pending = hashinit(syncer_maxdelay, M_VNODE, 335 &syncer_mask); 336 syncer_maxdelay = syncer_mask + 1; 337 mtx_init(&sync_mtx, "Syncer mtx", NULL, MTX_DEF); 338 cv_init(&sync_wakeup, "syncer"); 339 for (i = 1; i <= sizeof(struct vnode); i <<= 1) 340 vnsz2log++; 341 vnsz2log--; 342 } 343 SYSINIT(vfs, SI_SUB_VFS, SI_ORDER_FIRST, vntblinit, NULL); 344 345 346 /* 347 * Mark a mount point as busy. Used to synchronize access and to delay 348 * unmounting. Eventually, mountlist_mtx is not released on failure. 349 * 350 * vfs_busy() is a custom lock, it can block the caller. 351 * vfs_busy() only sleeps if the unmount is active on the mount point. 352 * For a mountpoint mp, vfs_busy-enforced lock is before lock of any 353 * vnode belonging to mp. 354 * 355 * Lookup uses vfs_busy() to traverse mount points. 356 * root fs var fs 357 * / vnode lock A / vnode lock (/var) D 358 * /var vnode lock B /log vnode lock(/var/log) E 359 * vfs_busy lock C vfs_busy lock F 360 * 361 * Within each file system, the lock order is C->A->B and F->D->E. 362 * 363 * When traversing across mounts, the system follows that lock order: 364 * 365 * C->A->B 366 * | 367 * +->F->D->E 368 * 369 * The lookup() process for namei("/var") illustrates the process: 370 * VOP_LOOKUP() obtains B while A is held 371 * vfs_busy() obtains a shared lock on F while A and B are held 372 * vput() releases lock on B 373 * vput() releases lock on A 374 * VFS_ROOT() obtains lock on D while shared lock on F is held 375 * vfs_unbusy() releases shared lock on F 376 * vn_lock() obtains lock on deadfs vnode vp_crossmp instead of A. 377 * Attempt to lock A (instead of vp_crossmp) while D is held would 378 * violate the global order, causing deadlocks. 379 * 380 * dounmount() locks B while F is drained. 381 */ 382 int 383 vfs_busy(struct mount *mp, int flags) 384 { 385 386 MPASS((flags & ~MBF_MASK) == 0); 387 CTR3(KTR_VFS, "%s: mp %p with flags %d", __func__, mp, flags); 388 389 MNT_ILOCK(mp); 390 MNT_REF(mp); 391 /* 392 * If mount point is currenly being unmounted, sleep until the 393 * mount point fate is decided. If thread doing the unmounting fails, 394 * it will clear MNTK_UNMOUNT flag before waking us up, indicating 395 * that this mount point has survived the unmount attempt and vfs_busy 396 * should retry. Otherwise the unmounter thread will set MNTK_REFEXPIRE 397 * flag in addition to MNTK_UNMOUNT, indicating that mount point is 398 * about to be really destroyed. vfs_busy needs to release its 399 * reference on the mount point in this case and return with ENOENT, 400 * telling the caller that mount mount it tried to busy is no longer 401 * valid. 402 */ 403 while (mp->mnt_kern_flag & MNTK_UNMOUNT) { 404 if (flags & MBF_NOWAIT || mp->mnt_kern_flag & MNTK_REFEXPIRE) { 405 MNT_REL(mp); 406 MNT_IUNLOCK(mp); 407 CTR1(KTR_VFS, "%s: failed busying before sleeping", 408 __func__); 409 return (ENOENT); 410 } 411 if (flags & MBF_MNTLSTLOCK) 412 mtx_unlock(&mountlist_mtx); 413 mp->mnt_kern_flag |= MNTK_MWAIT; 414 msleep(mp, MNT_MTX(mp), PVFS | PDROP, "vfs_busy", 0); 415 if (flags & MBF_MNTLSTLOCK) 416 mtx_lock(&mountlist_mtx); 417 MNT_ILOCK(mp); 418 } 419 if (flags & MBF_MNTLSTLOCK) 420 mtx_unlock(&mountlist_mtx); 421 mp->mnt_lockref++; 422 MNT_IUNLOCK(mp); 423 return (0); 424 } 425 426 /* 427 * Free a busy filesystem. 428 */ 429 void 430 vfs_unbusy(struct mount *mp) 431 { 432 433 CTR2(KTR_VFS, "%s: mp %p", __func__, mp); 434 MNT_ILOCK(mp); 435 MNT_REL(mp); 436 KASSERT(mp->mnt_lockref > 0, ("negative mnt_lockref")); 437 mp->mnt_lockref--; 438 if (mp->mnt_lockref == 0 && (mp->mnt_kern_flag & MNTK_DRAINING) != 0) { 439 MPASS(mp->mnt_kern_flag & MNTK_UNMOUNT); 440 CTR1(KTR_VFS, "%s: waking up waiters", __func__); 441 mp->mnt_kern_flag &= ~MNTK_DRAINING; 442 wakeup(&mp->mnt_lockref); 443 } 444 MNT_IUNLOCK(mp); 445 } 446 447 /* 448 * Lookup a mount point by filesystem identifier. 449 */ 450 struct mount * 451 vfs_getvfs(fsid_t *fsid) 452 { 453 struct mount *mp; 454 455 CTR2(KTR_VFS, "%s: fsid %p", __func__, fsid); 456 mtx_lock(&mountlist_mtx); 457 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 458 if (mp->mnt_stat.f_fsid.val[0] == fsid->val[0] && 459 mp->mnt_stat.f_fsid.val[1] == fsid->val[1]) { 460 vfs_ref(mp); 461 mtx_unlock(&mountlist_mtx); 462 return (mp); 463 } 464 } 465 mtx_unlock(&mountlist_mtx); 466 CTR2(KTR_VFS, "%s: lookup failed for %p id", __func__, fsid); 467 return ((struct mount *) 0); 468 } 469 470 /* 471 * Lookup a mount point by filesystem identifier, busying it before 472 * returning. 473 */ 474 struct mount * 475 vfs_busyfs(fsid_t *fsid) 476 { 477 struct mount *mp; 478 int error; 479 480 CTR2(KTR_VFS, "%s: fsid %p", __func__, fsid); 481 mtx_lock(&mountlist_mtx); 482 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 483 if (mp->mnt_stat.f_fsid.val[0] == fsid->val[0] && 484 mp->mnt_stat.f_fsid.val[1] == fsid->val[1]) { 485 error = vfs_busy(mp, MBF_MNTLSTLOCK); 486 if (error) { 487 mtx_unlock(&mountlist_mtx); 488 return (NULL); 489 } 490 return (mp); 491 } 492 } 493 CTR2(KTR_VFS, "%s: lookup failed for %p id", __func__, fsid); 494 mtx_unlock(&mountlist_mtx); 495 return ((struct mount *) 0); 496 } 497 498 /* 499 * Check if a user can access privileged mount options. 500 */ 501 int 502 vfs_suser(struct mount *mp, struct thread *td) 503 { 504 int error; 505 506 /* 507 * If the thread is jailed, but this is not a jail-friendly file 508 * system, deny immediately. 509 */ 510 if (!(mp->mnt_vfc->vfc_flags & VFCF_JAIL) && jailed(td->td_ucred)) 511 return (EPERM); 512 513 /* 514 * If the file system was mounted outside the jail of the calling 515 * thread, deny immediately. 516 */ 517 if (prison_check(td->td_ucred, mp->mnt_cred) != 0) 518 return (EPERM); 519 520 /* 521 * If file system supports delegated administration, we don't check 522 * for the PRIV_VFS_MOUNT_OWNER privilege - it will be better verified 523 * by the file system itself. 524 * If this is not the user that did original mount, we check for 525 * the PRIV_VFS_MOUNT_OWNER privilege. 526 */ 527 if (!(mp->mnt_vfc->vfc_flags & VFCF_DELEGADMIN) && 528 mp->mnt_cred->cr_uid != td->td_ucred->cr_uid) { 529 if ((error = priv_check(td, PRIV_VFS_MOUNT_OWNER)) != 0) 530 return (error); 531 } 532 return (0); 533 } 534 535 /* 536 * Get a new unique fsid. Try to make its val[0] unique, since this value 537 * will be used to create fake device numbers for stat(). Also try (but 538 * not so hard) make its val[0] unique mod 2^16, since some emulators only 539 * support 16-bit device numbers. We end up with unique val[0]'s for the 540 * first 2^16 calls and unique val[0]'s mod 2^16 for the first 2^8 calls. 541 * 542 * Keep in mind that several mounts may be running in parallel. Starting 543 * the search one past where the previous search terminated is both a 544 * micro-optimization and a defense against returning the same fsid to 545 * different mounts. 546 */ 547 void 548 vfs_getnewfsid(struct mount *mp) 549 { 550 static uint16_t mntid_base; 551 struct mount *nmp; 552 fsid_t tfsid; 553 int mtype; 554 555 CTR2(KTR_VFS, "%s: mp %p", __func__, mp); 556 mtx_lock(&mntid_mtx); 557 mtype = mp->mnt_vfc->vfc_typenum; 558 tfsid.val[1] = mtype; 559 mtype = (mtype & 0xFF) << 24; 560 for (;;) { 561 tfsid.val[0] = makedev(255, 562 mtype | ((mntid_base & 0xFF00) << 8) | (mntid_base & 0xFF)); 563 mntid_base++; 564 if ((nmp = vfs_getvfs(&tfsid)) == NULL) 565 break; 566 vfs_rel(nmp); 567 } 568 mp->mnt_stat.f_fsid.val[0] = tfsid.val[0]; 569 mp->mnt_stat.f_fsid.val[1] = tfsid.val[1]; 570 mtx_unlock(&mntid_mtx); 571 } 572 573 /* 574 * Knob to control the precision of file timestamps: 575 * 576 * 0 = seconds only; nanoseconds zeroed. 577 * 1 = seconds and nanoseconds, accurate within 1/HZ. 578 * 2 = seconds and nanoseconds, truncated to microseconds. 579 * >=3 = seconds and nanoseconds, maximum precision. 580 */ 581 enum { TSP_SEC, TSP_HZ, TSP_USEC, TSP_NSEC }; 582 583 static int timestamp_precision = TSP_SEC; 584 SYSCTL_INT(_vfs, OID_AUTO, timestamp_precision, CTLFLAG_RW, 585 ×tamp_precision, 0, "File timestamp precision (0: seconds, " 586 "1: sec + ns accurate to 1/HZ, 2: sec + ns truncated to ms, " 587 "3+: sec + ns (max. precision))"); 588 589 /* 590 * Get a current timestamp. 591 */ 592 void 593 vfs_timestamp(struct timespec *tsp) 594 { 595 struct timeval tv; 596 597 switch (timestamp_precision) { 598 case TSP_SEC: 599 tsp->tv_sec = time_second; 600 tsp->tv_nsec = 0; 601 break; 602 case TSP_HZ: 603 getnanotime(tsp); 604 break; 605 case TSP_USEC: 606 microtime(&tv); 607 TIMEVAL_TO_TIMESPEC(&tv, tsp); 608 break; 609 case TSP_NSEC: 610 default: 611 nanotime(tsp); 612 break; 613 } 614 } 615 616 /* 617 * Set vnode attributes to VNOVAL 618 */ 619 void 620 vattr_null(struct vattr *vap) 621 { 622 623 vap->va_type = VNON; 624 vap->va_size = VNOVAL; 625 vap->va_bytes = VNOVAL; 626 vap->va_mode = VNOVAL; 627 vap->va_nlink = VNOVAL; 628 vap->va_uid = VNOVAL; 629 vap->va_gid = VNOVAL; 630 vap->va_fsid = VNOVAL; 631 vap->va_fileid = VNOVAL; 632 vap->va_blocksize = VNOVAL; 633 vap->va_rdev = VNOVAL; 634 vap->va_atime.tv_sec = VNOVAL; 635 vap->va_atime.tv_nsec = VNOVAL; 636 vap->va_mtime.tv_sec = VNOVAL; 637 vap->va_mtime.tv_nsec = VNOVAL; 638 vap->va_ctime.tv_sec = VNOVAL; 639 vap->va_ctime.tv_nsec = VNOVAL; 640 vap->va_birthtime.tv_sec = VNOVAL; 641 vap->va_birthtime.tv_nsec = VNOVAL; 642 vap->va_flags = VNOVAL; 643 vap->va_gen = VNOVAL; 644 vap->va_vaflags = 0; 645 } 646 647 /* 648 * This routine is called when we have too many vnodes. It attempts 649 * to free <count> vnodes and will potentially free vnodes that still 650 * have VM backing store (VM backing store is typically the cause 651 * of a vnode blowout so we want to do this). Therefore, this operation 652 * is not considered cheap. 653 * 654 * A number of conditions may prevent a vnode from being reclaimed. 655 * the buffer cache may have references on the vnode, a directory 656 * vnode may still have references due to the namei cache representing 657 * underlying files, or the vnode may be in active use. It is not 658 * desireable to reuse such vnodes. These conditions may cause the 659 * number of vnodes to reach some minimum value regardless of what 660 * you set kern.maxvnodes to. Do not set kern.maxvnodes too low. 661 */ 662 static int 663 vlrureclaim(struct mount *mp) 664 { 665 struct vnode *vp; 666 int done; 667 int trigger; 668 int usevnodes; 669 int count; 670 671 /* 672 * Calculate the trigger point, don't allow user 673 * screwups to blow us up. This prevents us from 674 * recycling vnodes with lots of resident pages. We 675 * aren't trying to free memory, we are trying to 676 * free vnodes. 677 */ 678 usevnodes = desiredvnodes; 679 if (usevnodes <= 0) 680 usevnodes = 1; 681 trigger = cnt.v_page_count * 2 / usevnodes; 682 done = 0; 683 vn_start_write(NULL, &mp, V_WAIT); 684 MNT_ILOCK(mp); 685 count = mp->mnt_nvnodelistsize / 10 + 1; 686 while (count != 0) { 687 vp = TAILQ_FIRST(&mp->mnt_nvnodelist); 688 while (vp != NULL && vp->v_type == VMARKER) 689 vp = TAILQ_NEXT(vp, v_nmntvnodes); 690 if (vp == NULL) 691 break; 692 TAILQ_REMOVE(&mp->mnt_nvnodelist, vp, v_nmntvnodes); 693 TAILQ_INSERT_TAIL(&mp->mnt_nvnodelist, vp, v_nmntvnodes); 694 --count; 695 if (!VI_TRYLOCK(vp)) 696 goto next_iter; 697 /* 698 * If it's been deconstructed already, it's still 699 * referenced, or it exceeds the trigger, skip it. 700 */ 701 if (vp->v_usecount || 702 (!vlru_allow_cache_src && 703 !LIST_EMPTY(&(vp)->v_cache_src)) || 704 (vp->v_iflag & VI_DOOMED) != 0 || (vp->v_object != NULL && 705 vp->v_object->resident_page_count > trigger)) { 706 VI_UNLOCK(vp); 707 goto next_iter; 708 } 709 MNT_IUNLOCK(mp); 710 vholdl(vp); 711 if (VOP_LOCK(vp, LK_INTERLOCK|LK_EXCLUSIVE|LK_NOWAIT)) { 712 vdrop(vp); 713 goto next_iter_mntunlocked; 714 } 715 VI_LOCK(vp); 716 /* 717 * v_usecount may have been bumped after VOP_LOCK() dropped 718 * the vnode interlock and before it was locked again. 719 * 720 * It is not necessary to recheck VI_DOOMED because it can 721 * only be set by another thread that holds both the vnode 722 * lock and vnode interlock. If another thread has the 723 * vnode lock before we get to VOP_LOCK() and obtains the 724 * vnode interlock after VOP_LOCK() drops the vnode 725 * interlock, the other thread will be unable to drop the 726 * vnode lock before our VOP_LOCK() call fails. 727 */ 728 if (vp->v_usecount || 729 (!vlru_allow_cache_src && 730 !LIST_EMPTY(&(vp)->v_cache_src)) || 731 (vp->v_object != NULL && 732 vp->v_object->resident_page_count > trigger)) { 733 VOP_UNLOCK(vp, LK_INTERLOCK); 734 goto next_iter_mntunlocked; 735 } 736 KASSERT((vp->v_iflag & VI_DOOMED) == 0, 737 ("VI_DOOMED unexpectedly detected in vlrureclaim()")); 738 vgonel(vp); 739 VOP_UNLOCK(vp, 0); 740 vdropl(vp); 741 done++; 742 next_iter_mntunlocked: 743 if (!should_yield()) 744 goto relock_mnt; 745 goto yield; 746 next_iter: 747 if (!should_yield()) 748 continue; 749 MNT_IUNLOCK(mp); 750 yield: 751 kern_yield(PRI_USER); 752 relock_mnt: 753 MNT_ILOCK(mp); 754 } 755 MNT_IUNLOCK(mp); 756 vn_finished_write(mp); 757 return done; 758 } 759 760 /* 761 * Attempt to keep the free list at wantfreevnodes length. 762 */ 763 static void 764 vnlru_free(int count) 765 { 766 struct vnode *vp; 767 768 mtx_assert(&vnode_free_list_mtx, MA_OWNED); 769 for (; count > 0; count--) { 770 vp = TAILQ_FIRST(&vnode_free_list); 771 /* 772 * The list can be modified while the free_list_mtx 773 * has been dropped and vp could be NULL here. 774 */ 775 if (!vp) 776 break; 777 VNASSERT(vp->v_op != NULL, vp, 778 ("vnlru_free: vnode already reclaimed.")); 779 KASSERT((vp->v_iflag & VI_FREE) != 0, 780 ("Removing vnode not on freelist")); 781 KASSERT((vp->v_iflag & VI_ACTIVE) == 0, 782 ("Mangling active vnode")); 783 TAILQ_REMOVE(&vnode_free_list, vp, v_actfreelist); 784 /* 785 * Don't recycle if we can't get the interlock. 786 */ 787 if (!VI_TRYLOCK(vp)) { 788 TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_actfreelist); 789 continue; 790 } 791 VNASSERT(VCANRECYCLE(vp), vp, 792 ("vp inconsistent on freelist")); 793 freevnodes--; 794 vp->v_iflag &= ~VI_FREE; 795 vholdl(vp); 796 mtx_unlock(&vnode_free_list_mtx); 797 VI_UNLOCK(vp); 798 vtryrecycle(vp); 799 /* 800 * If the recycled succeeded this vdrop will actually free 801 * the vnode. If not it will simply place it back on 802 * the free list. 803 */ 804 vdrop(vp); 805 mtx_lock(&vnode_free_list_mtx); 806 } 807 } 808 /* 809 * Attempt to recycle vnodes in a context that is always safe to block. 810 * Calling vlrurecycle() from the bowels of filesystem code has some 811 * interesting deadlock problems. 812 */ 813 static struct proc *vnlruproc; 814 static int vnlruproc_sig; 815 816 static void 817 vnlru_proc(void) 818 { 819 struct mount *mp, *nmp; 820 int done; 821 struct proc *p = vnlruproc; 822 823 EVENTHANDLER_REGISTER(shutdown_pre_sync, kproc_shutdown, p, 824 SHUTDOWN_PRI_FIRST); 825 826 for (;;) { 827 kproc_suspend_check(p); 828 mtx_lock(&vnode_free_list_mtx); 829 if (freevnodes > wantfreevnodes) 830 vnlru_free(freevnodes - wantfreevnodes); 831 if (numvnodes <= desiredvnodes * 9 / 10) { 832 vnlruproc_sig = 0; 833 wakeup(&vnlruproc_sig); 834 msleep(vnlruproc, &vnode_free_list_mtx, 835 PVFS|PDROP, "vlruwt", hz); 836 continue; 837 } 838 mtx_unlock(&vnode_free_list_mtx); 839 done = 0; 840 mtx_lock(&mountlist_mtx); 841 for (mp = TAILQ_FIRST(&mountlist); mp != NULL; mp = nmp) { 842 if (vfs_busy(mp, MBF_NOWAIT | MBF_MNTLSTLOCK)) { 843 nmp = TAILQ_NEXT(mp, mnt_list); 844 continue; 845 } 846 done += vlrureclaim(mp); 847 mtx_lock(&mountlist_mtx); 848 nmp = TAILQ_NEXT(mp, mnt_list); 849 vfs_unbusy(mp); 850 } 851 mtx_unlock(&mountlist_mtx); 852 if (done == 0) { 853 #if 0 854 /* These messages are temporary debugging aids */ 855 if (vnlru_nowhere < 5) 856 printf("vnlru process getting nowhere..\n"); 857 else if (vnlru_nowhere == 5) 858 printf("vnlru process messages stopped.\n"); 859 #endif 860 vnlru_nowhere++; 861 tsleep(vnlruproc, PPAUSE, "vlrup", hz * 3); 862 } else 863 kern_yield(PRI_USER); 864 } 865 } 866 867 static struct kproc_desc vnlru_kp = { 868 "vnlru", 869 vnlru_proc, 870 &vnlruproc 871 }; 872 SYSINIT(vnlru, SI_SUB_KTHREAD_UPDATE, SI_ORDER_FIRST, kproc_start, 873 &vnlru_kp); 874 875 /* 876 * Routines having to do with the management of the vnode table. 877 */ 878 879 /* 880 * Try to recycle a freed vnode. We abort if anyone picks up a reference 881 * before we actually vgone(). This function must be called with the vnode 882 * held to prevent the vnode from being returned to the free list midway 883 * through vgone(). 884 */ 885 static int 886 vtryrecycle(struct vnode *vp) 887 { 888 struct mount *vnmp; 889 890 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 891 VNASSERT(vp->v_holdcnt, vp, 892 ("vtryrecycle: Recycling vp %p without a reference.", vp)); 893 /* 894 * This vnode may found and locked via some other list, if so we 895 * can't recycle it yet. 896 */ 897 if (VOP_LOCK(vp, LK_EXCLUSIVE | LK_NOWAIT) != 0) { 898 CTR2(KTR_VFS, 899 "%s: impossible to recycle, vp %p lock is already held", 900 __func__, vp); 901 return (EWOULDBLOCK); 902 } 903 /* 904 * Don't recycle if its filesystem is being suspended. 905 */ 906 if (vn_start_write(vp, &vnmp, V_NOWAIT) != 0) { 907 VOP_UNLOCK(vp, 0); 908 CTR2(KTR_VFS, 909 "%s: impossible to recycle, cannot start the write for %p", 910 __func__, vp); 911 return (EBUSY); 912 } 913 /* 914 * If we got this far, we need to acquire the interlock and see if 915 * anyone picked up this vnode from another list. If not, we will 916 * mark it with DOOMED via vgonel() so that anyone who does find it 917 * will skip over it. 918 */ 919 VI_LOCK(vp); 920 if (vp->v_usecount) { 921 VOP_UNLOCK(vp, LK_INTERLOCK); 922 vn_finished_write(vnmp); 923 CTR2(KTR_VFS, 924 "%s: impossible to recycle, %p is already referenced", 925 __func__, vp); 926 return (EBUSY); 927 } 928 if ((vp->v_iflag & VI_DOOMED) == 0) 929 vgonel(vp); 930 VOP_UNLOCK(vp, LK_INTERLOCK); 931 vn_finished_write(vnmp); 932 return (0); 933 } 934 935 /* 936 * Wait for available vnodes. 937 */ 938 static int 939 getnewvnode_wait(int suspended) 940 { 941 942 mtx_assert(&vnode_free_list_mtx, MA_OWNED); 943 if (numvnodes > desiredvnodes) { 944 if (suspended) { 945 /* 946 * File system is beeing suspended, we cannot risk a 947 * deadlock here, so allocate new vnode anyway. 948 */ 949 if (freevnodes > wantfreevnodes) 950 vnlru_free(freevnodes - wantfreevnodes); 951 return (0); 952 } 953 if (vnlruproc_sig == 0) { 954 vnlruproc_sig = 1; /* avoid unnecessary wakeups */ 955 wakeup(vnlruproc); 956 } 957 msleep(&vnlruproc_sig, &vnode_free_list_mtx, PVFS, 958 "vlruwk", hz); 959 } 960 return (numvnodes > desiredvnodes ? ENFILE : 0); 961 } 962 963 void 964 getnewvnode_reserve(u_int count) 965 { 966 struct thread *td; 967 968 td = curthread; 969 mtx_lock(&vnode_free_list_mtx); 970 while (count > 0) { 971 if (getnewvnode_wait(0) == 0) { 972 count--; 973 td->td_vp_reserv++; 974 numvnodes++; 975 } 976 } 977 mtx_unlock(&vnode_free_list_mtx); 978 } 979 980 void 981 getnewvnode_drop_reserve(void) 982 { 983 struct thread *td; 984 985 td = curthread; 986 mtx_lock(&vnode_free_list_mtx); 987 KASSERT(numvnodes >= td->td_vp_reserv, ("reserve too large")); 988 numvnodes -= td->td_vp_reserv; 989 mtx_unlock(&vnode_free_list_mtx); 990 td->td_vp_reserv = 0; 991 } 992 993 /* 994 * Return the next vnode from the free list. 995 */ 996 int 997 getnewvnode(const char *tag, struct mount *mp, struct vop_vector *vops, 998 struct vnode **vpp) 999 { 1000 struct vnode *vp; 1001 struct bufobj *bo; 1002 struct thread *td; 1003 int error; 1004 1005 CTR3(KTR_VFS, "%s: mp %p with tag %s", __func__, mp, tag); 1006 vp = NULL; 1007 td = curthread; 1008 if (td->td_vp_reserv > 0) { 1009 td->td_vp_reserv -= 1; 1010 goto alloc; 1011 } 1012 mtx_lock(&vnode_free_list_mtx); 1013 /* 1014 * Lend our context to reclaim vnodes if they've exceeded the max. 1015 */ 1016 if (freevnodes > wantfreevnodes) 1017 vnlru_free(1); 1018 error = getnewvnode_wait(mp != NULL && (mp->mnt_kern_flag & 1019 MNTK_SUSPEND)); 1020 #if 0 /* XXX Not all VFS_VGET/ffs_vget callers check returns. */ 1021 if (error != 0) { 1022 mtx_unlock(&vnode_free_list_mtx); 1023 return (error); 1024 } 1025 #endif 1026 numvnodes++; 1027 mtx_unlock(&vnode_free_list_mtx); 1028 alloc: 1029 vp = (struct vnode *) uma_zalloc(vnode_zone, M_WAITOK|M_ZERO); 1030 /* 1031 * Setup locks. 1032 */ 1033 vp->v_vnlock = &vp->v_lock; 1034 mtx_init(&vp->v_interlock, "vnode interlock", NULL, MTX_DEF); 1035 /* 1036 * By default, don't allow shared locks unless filesystems 1037 * opt-in. 1038 */ 1039 lockinit(vp->v_vnlock, PVFS, tag, VLKTIMEOUT, LK_NOSHARE); 1040 /* 1041 * Initialize bufobj. 1042 */ 1043 bo = &vp->v_bufobj; 1044 bo->__bo_vnode = vp; 1045 mtx_init(BO_MTX(bo), "bufobj interlock", NULL, MTX_DEF); 1046 bo->bo_ops = &buf_ops_bio; 1047 bo->bo_private = vp; 1048 TAILQ_INIT(&bo->bo_clean.bv_hd); 1049 TAILQ_INIT(&bo->bo_dirty.bv_hd); 1050 /* 1051 * Initialize namecache. 1052 */ 1053 LIST_INIT(&vp->v_cache_src); 1054 TAILQ_INIT(&vp->v_cache_dst); 1055 /* 1056 * Finalize various vnode identity bits. 1057 */ 1058 vp->v_type = VNON; 1059 vp->v_tag = tag; 1060 vp->v_op = vops; 1061 v_incr_usecount(vp); 1062 vp->v_data = NULL; 1063 #ifdef MAC 1064 mac_vnode_init(vp); 1065 if (mp != NULL && (mp->mnt_flag & MNT_MULTILABEL) == 0) 1066 mac_vnode_associate_singlelabel(mp, vp); 1067 else if (mp == NULL && vops != &dead_vnodeops) 1068 printf("NULL mp in getnewvnode()\n"); 1069 #endif 1070 if (mp != NULL) { 1071 bo->bo_bsize = mp->mnt_stat.f_iosize; 1072 if ((mp->mnt_kern_flag & MNTK_NOKNOTE) != 0) 1073 vp->v_vflag |= VV_NOKNOTE; 1074 } 1075 rangelock_init(&vp->v_rl); 1076 1077 /* 1078 * For the filesystems which do not use vfs_hash_insert(), 1079 * still initialize v_hash to have vfs_hash_index() useful. 1080 * E.g., nullfs uses vfs_hash_index() on the lower vnode for 1081 * its own hashing. 1082 */ 1083 vp->v_hash = (uintptr_t)vp >> vnsz2log; 1084 1085 *vpp = vp; 1086 return (0); 1087 } 1088 1089 /* 1090 * Delete from old mount point vnode list, if on one. 1091 */ 1092 static void 1093 delmntque(struct vnode *vp) 1094 { 1095 struct mount *mp; 1096 int active; 1097 1098 mp = vp->v_mount; 1099 if (mp == NULL) 1100 return; 1101 MNT_ILOCK(mp); 1102 VI_LOCK(vp); 1103 KASSERT(mp->mnt_activevnodelistsize <= mp->mnt_nvnodelistsize, 1104 ("Active vnode list size %d > Vnode list size %d", 1105 mp->mnt_activevnodelistsize, mp->mnt_nvnodelistsize)); 1106 active = vp->v_iflag & VI_ACTIVE; 1107 vp->v_iflag &= ~VI_ACTIVE; 1108 if (active) { 1109 mtx_lock(&vnode_free_list_mtx); 1110 TAILQ_REMOVE(&mp->mnt_activevnodelist, vp, v_actfreelist); 1111 mp->mnt_activevnodelistsize--; 1112 mtx_unlock(&vnode_free_list_mtx); 1113 } 1114 vp->v_mount = NULL; 1115 VI_UNLOCK(vp); 1116 VNASSERT(mp->mnt_nvnodelistsize > 0, vp, 1117 ("bad mount point vnode list size")); 1118 TAILQ_REMOVE(&mp->mnt_nvnodelist, vp, v_nmntvnodes); 1119 mp->mnt_nvnodelistsize--; 1120 MNT_REL(mp); 1121 MNT_IUNLOCK(mp); 1122 } 1123 1124 static void 1125 insmntque_stddtr(struct vnode *vp, void *dtr_arg) 1126 { 1127 1128 vp->v_data = NULL; 1129 vp->v_op = &dead_vnodeops; 1130 vgone(vp); 1131 vput(vp); 1132 } 1133 1134 /* 1135 * Insert into list of vnodes for the new mount point, if available. 1136 */ 1137 int 1138 insmntque1(struct vnode *vp, struct mount *mp, 1139 void (*dtr)(struct vnode *, void *), void *dtr_arg) 1140 { 1141 1142 KASSERT(vp->v_mount == NULL, 1143 ("insmntque: vnode already on per mount vnode list")); 1144 VNASSERT(mp != NULL, vp, ("Don't call insmntque(foo, NULL)")); 1145 ASSERT_VOP_ELOCKED(vp, "insmntque: non-locked vp"); 1146 1147 /* 1148 * We acquire the vnode interlock early to ensure that the 1149 * vnode cannot be recycled by another process releasing a 1150 * holdcnt on it before we get it on both the vnode list 1151 * and the active vnode list. The mount mutex protects only 1152 * manipulation of the vnode list and the vnode freelist 1153 * mutex protects only manipulation of the active vnode list. 1154 * Hence the need to hold the vnode interlock throughout. 1155 */ 1156 MNT_ILOCK(mp); 1157 VI_LOCK(vp); 1158 if (((mp->mnt_kern_flag & MNTK_NOINSMNTQ) != 0 && 1159 ((mp->mnt_kern_flag & MNTK_UNMOUNTF) != 0 || 1160 mp->mnt_nvnodelistsize == 0)) && 1161 (vp->v_vflag & VV_FORCEINSMQ) == 0) { 1162 VI_UNLOCK(vp); 1163 MNT_IUNLOCK(mp); 1164 if (dtr != NULL) 1165 dtr(vp, dtr_arg); 1166 return (EBUSY); 1167 } 1168 vp->v_mount = mp; 1169 MNT_REF(mp); 1170 TAILQ_INSERT_TAIL(&mp->mnt_nvnodelist, vp, v_nmntvnodes); 1171 VNASSERT(mp->mnt_nvnodelistsize >= 0, vp, 1172 ("neg mount point vnode list size")); 1173 mp->mnt_nvnodelistsize++; 1174 KASSERT((vp->v_iflag & VI_ACTIVE) == 0, 1175 ("Activating already active vnode")); 1176 vp->v_iflag |= VI_ACTIVE; 1177 mtx_lock(&vnode_free_list_mtx); 1178 TAILQ_INSERT_HEAD(&mp->mnt_activevnodelist, vp, v_actfreelist); 1179 mp->mnt_activevnodelistsize++; 1180 mtx_unlock(&vnode_free_list_mtx); 1181 VI_UNLOCK(vp); 1182 MNT_IUNLOCK(mp); 1183 return (0); 1184 } 1185 1186 int 1187 insmntque(struct vnode *vp, struct mount *mp) 1188 { 1189 1190 return (insmntque1(vp, mp, insmntque_stddtr, NULL)); 1191 } 1192 1193 /* 1194 * Flush out and invalidate all buffers associated with a bufobj 1195 * Called with the underlying object locked. 1196 */ 1197 int 1198 bufobj_invalbuf(struct bufobj *bo, int flags, int slpflag, int slptimeo) 1199 { 1200 int error; 1201 1202 BO_LOCK(bo); 1203 if (flags & V_SAVE) { 1204 error = bufobj_wwait(bo, slpflag, slptimeo); 1205 if (error) { 1206 BO_UNLOCK(bo); 1207 return (error); 1208 } 1209 if (bo->bo_dirty.bv_cnt > 0) { 1210 BO_UNLOCK(bo); 1211 if ((error = BO_SYNC(bo, MNT_WAIT)) != 0) 1212 return (error); 1213 /* 1214 * XXX We could save a lock/unlock if this was only 1215 * enabled under INVARIANTS 1216 */ 1217 BO_LOCK(bo); 1218 if (bo->bo_numoutput > 0 || bo->bo_dirty.bv_cnt > 0) 1219 panic("vinvalbuf: dirty bufs"); 1220 } 1221 } 1222 /* 1223 * If you alter this loop please notice that interlock is dropped and 1224 * reacquired in flushbuflist. Special care is needed to ensure that 1225 * no race conditions occur from this. 1226 */ 1227 do { 1228 error = flushbuflist(&bo->bo_clean, 1229 flags, bo, slpflag, slptimeo); 1230 if (error == 0 && !(flags & V_CLEANONLY)) 1231 error = flushbuflist(&bo->bo_dirty, 1232 flags, bo, slpflag, slptimeo); 1233 if (error != 0 && error != EAGAIN) { 1234 BO_UNLOCK(bo); 1235 return (error); 1236 } 1237 } while (error != 0); 1238 1239 /* 1240 * Wait for I/O to complete. XXX needs cleaning up. The vnode can 1241 * have write I/O in-progress but if there is a VM object then the 1242 * VM object can also have read-I/O in-progress. 1243 */ 1244 do { 1245 bufobj_wwait(bo, 0, 0); 1246 BO_UNLOCK(bo); 1247 if (bo->bo_object != NULL) { 1248 VM_OBJECT_WLOCK(bo->bo_object); 1249 vm_object_pip_wait(bo->bo_object, "bovlbx"); 1250 VM_OBJECT_WUNLOCK(bo->bo_object); 1251 } 1252 BO_LOCK(bo); 1253 } while (bo->bo_numoutput > 0); 1254 BO_UNLOCK(bo); 1255 1256 /* 1257 * Destroy the copy in the VM cache, too. 1258 */ 1259 if (bo->bo_object != NULL && 1260 (flags & (V_ALT | V_NORMAL | V_CLEANONLY)) == 0) { 1261 VM_OBJECT_WLOCK(bo->bo_object); 1262 vm_object_page_remove(bo->bo_object, 0, 0, (flags & V_SAVE) ? 1263 OBJPR_CLEANONLY : 0); 1264 VM_OBJECT_WUNLOCK(bo->bo_object); 1265 } 1266 1267 #ifdef INVARIANTS 1268 BO_LOCK(bo); 1269 if ((flags & (V_ALT | V_NORMAL | V_CLEANONLY)) == 0 && 1270 (bo->bo_dirty.bv_cnt > 0 || bo->bo_clean.bv_cnt > 0)) 1271 panic("vinvalbuf: flush failed"); 1272 BO_UNLOCK(bo); 1273 #endif 1274 return (0); 1275 } 1276 1277 /* 1278 * Flush out and invalidate all buffers associated with a vnode. 1279 * Called with the underlying object locked. 1280 */ 1281 int 1282 vinvalbuf(struct vnode *vp, int flags, int slpflag, int slptimeo) 1283 { 1284 1285 CTR3(KTR_VFS, "%s: vp %p with flags %d", __func__, vp, flags); 1286 ASSERT_VOP_LOCKED(vp, "vinvalbuf"); 1287 return (bufobj_invalbuf(&vp->v_bufobj, flags, slpflag, slptimeo)); 1288 } 1289 1290 /* 1291 * Flush out buffers on the specified list. 1292 * 1293 */ 1294 static int 1295 flushbuflist(struct bufv *bufv, int flags, struct bufobj *bo, int slpflag, 1296 int slptimeo) 1297 { 1298 struct buf *bp, *nbp; 1299 int retval, error; 1300 daddr_t lblkno; 1301 b_xflags_t xflags; 1302 1303 ASSERT_BO_LOCKED(bo); 1304 1305 retval = 0; 1306 TAILQ_FOREACH_SAFE(bp, &bufv->bv_hd, b_bobufs, nbp) { 1307 if (((flags & V_NORMAL) && (bp->b_xflags & BX_ALTDATA)) || 1308 ((flags & V_ALT) && (bp->b_xflags & BX_ALTDATA) == 0)) { 1309 continue; 1310 } 1311 lblkno = 0; 1312 xflags = 0; 1313 if (nbp != NULL) { 1314 lblkno = nbp->b_lblkno; 1315 xflags = nbp->b_xflags & 1316 (BX_BKGRDMARKER | BX_VNDIRTY | BX_VNCLEAN); 1317 } 1318 retval = EAGAIN; 1319 error = BUF_TIMELOCK(bp, 1320 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, BO_MTX(bo), 1321 "flushbuf", slpflag, slptimeo); 1322 if (error) { 1323 BO_LOCK(bo); 1324 return (error != ENOLCK ? error : EAGAIN); 1325 } 1326 KASSERT(bp->b_bufobj == bo, 1327 ("bp %p wrong b_bufobj %p should be %p", 1328 bp, bp->b_bufobj, bo)); 1329 if (bp->b_bufobj != bo) { /* XXX: necessary ? */ 1330 BUF_UNLOCK(bp); 1331 BO_LOCK(bo); 1332 return (EAGAIN); 1333 } 1334 /* 1335 * XXX Since there are no node locks for NFS, I 1336 * believe there is a slight chance that a delayed 1337 * write will occur while sleeping just above, so 1338 * check for it. 1339 */ 1340 if (((bp->b_flags & (B_DELWRI | B_INVAL)) == B_DELWRI) && 1341 (flags & V_SAVE)) { 1342 BO_LOCK(bo); 1343 bremfree(bp); 1344 BO_UNLOCK(bo); 1345 bp->b_flags |= B_ASYNC; 1346 bwrite(bp); 1347 BO_LOCK(bo); 1348 return (EAGAIN); /* XXX: why not loop ? */ 1349 } 1350 BO_LOCK(bo); 1351 bremfree(bp); 1352 BO_UNLOCK(bo); 1353 bp->b_flags |= (B_INVAL | B_RELBUF); 1354 bp->b_flags &= ~B_ASYNC; 1355 brelse(bp); 1356 BO_LOCK(bo); 1357 if (nbp != NULL && 1358 (nbp->b_bufobj != bo || 1359 nbp->b_lblkno != lblkno || 1360 (nbp->b_xflags & 1361 (BX_BKGRDMARKER | BX_VNDIRTY | BX_VNCLEAN)) != xflags)) 1362 break; /* nbp invalid */ 1363 } 1364 return (retval); 1365 } 1366 1367 /* 1368 * Truncate a file's buffer and pages to a specified length. This 1369 * is in lieu of the old vinvalbuf mechanism, which performed unneeded 1370 * sync activity. 1371 */ 1372 int 1373 vtruncbuf(struct vnode *vp, struct ucred *cred, off_t length, int blksize) 1374 { 1375 struct buf *bp, *nbp; 1376 int anyfreed; 1377 int trunclbn; 1378 struct bufobj *bo; 1379 1380 CTR5(KTR_VFS, "%s: vp %p with cred %p and block %d:%ju", __func__, 1381 vp, cred, blksize, (uintmax_t)length); 1382 1383 /* 1384 * Round up to the *next* lbn. 1385 */ 1386 trunclbn = (length + blksize - 1) / blksize; 1387 1388 ASSERT_VOP_LOCKED(vp, "vtruncbuf"); 1389 restart: 1390 bo = &vp->v_bufobj; 1391 BO_LOCK(bo); 1392 anyfreed = 1; 1393 for (;anyfreed;) { 1394 anyfreed = 0; 1395 TAILQ_FOREACH_SAFE(bp, &bo->bo_clean.bv_hd, b_bobufs, nbp) { 1396 if (bp->b_lblkno < trunclbn) 1397 continue; 1398 if (BUF_LOCK(bp, 1399 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, 1400 BO_MTX(bo)) == ENOLCK) 1401 goto restart; 1402 1403 BO_LOCK(bo); 1404 bremfree(bp); 1405 BO_UNLOCK(bo); 1406 bp->b_flags |= (B_INVAL | B_RELBUF); 1407 bp->b_flags &= ~B_ASYNC; 1408 brelse(bp); 1409 anyfreed = 1; 1410 1411 BO_LOCK(bo); 1412 if (nbp != NULL && 1413 (((nbp->b_xflags & BX_VNCLEAN) == 0) || 1414 (nbp->b_vp != vp) || 1415 (nbp->b_flags & B_DELWRI))) { 1416 BO_UNLOCK(bo); 1417 goto restart; 1418 } 1419 } 1420 1421 TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) { 1422 if (bp->b_lblkno < trunclbn) 1423 continue; 1424 if (BUF_LOCK(bp, 1425 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, 1426 BO_MTX(bo)) == ENOLCK) 1427 goto restart; 1428 BO_LOCK(bo); 1429 bremfree(bp); 1430 BO_UNLOCK(bo); 1431 bp->b_flags |= (B_INVAL | B_RELBUF); 1432 bp->b_flags &= ~B_ASYNC; 1433 brelse(bp); 1434 anyfreed = 1; 1435 1436 BO_LOCK(bo); 1437 if (nbp != NULL && 1438 (((nbp->b_xflags & BX_VNDIRTY) == 0) || 1439 (nbp->b_vp != vp) || 1440 (nbp->b_flags & B_DELWRI) == 0)) { 1441 BO_UNLOCK(bo); 1442 goto restart; 1443 } 1444 } 1445 } 1446 1447 if (length > 0) { 1448 restartsync: 1449 TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) { 1450 if (bp->b_lblkno > 0) 1451 continue; 1452 /* 1453 * Since we hold the vnode lock this should only 1454 * fail if we're racing with the buf daemon. 1455 */ 1456 if (BUF_LOCK(bp, 1457 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, 1458 BO_MTX(bo)) == ENOLCK) { 1459 goto restart; 1460 } 1461 VNASSERT((bp->b_flags & B_DELWRI), vp, 1462 ("buf(%p) on dirty queue without DELWRI", bp)); 1463 1464 BO_LOCK(bo); 1465 bremfree(bp); 1466 BO_UNLOCK(bo); 1467 bawrite(bp); 1468 BO_LOCK(bo); 1469 goto restartsync; 1470 } 1471 } 1472 1473 bufobj_wwait(bo, 0, 0); 1474 BO_UNLOCK(bo); 1475 vnode_pager_setsize(vp, length); 1476 1477 return (0); 1478 } 1479 1480 /* 1481 * buf_splay() - splay tree core for the clean/dirty list of buffers in 1482 * a vnode. 1483 * 1484 * NOTE: We have to deal with the special case of a background bitmap 1485 * buffer, a situation where two buffers will have the same logical 1486 * block offset. We want (1) only the foreground buffer to be accessed 1487 * in a lookup and (2) must differentiate between the foreground and 1488 * background buffer in the splay tree algorithm because the splay 1489 * tree cannot normally handle multiple entities with the same 'index'. 1490 * We accomplish this by adding differentiating flags to the splay tree's 1491 * numerical domain. 1492 */ 1493 static 1494 struct buf * 1495 buf_splay(daddr_t lblkno, b_xflags_t xflags, struct buf *root) 1496 { 1497 struct buf dummy; 1498 struct buf *lefttreemax, *righttreemin, *y; 1499 1500 if (root == NULL) 1501 return (NULL); 1502 lefttreemax = righttreemin = &dummy; 1503 for (;;) { 1504 if (lblkno < root->b_lblkno || 1505 (lblkno == root->b_lblkno && 1506 (xflags & BX_BKGRDMARKER) < (root->b_xflags & BX_BKGRDMARKER))) { 1507 if ((y = root->b_left) == NULL) 1508 break; 1509 if (lblkno < y->b_lblkno) { 1510 /* Rotate right. */ 1511 root->b_left = y->b_right; 1512 y->b_right = root; 1513 root = y; 1514 if ((y = root->b_left) == NULL) 1515 break; 1516 } 1517 /* Link into the new root's right tree. */ 1518 righttreemin->b_left = root; 1519 righttreemin = root; 1520 } else if (lblkno > root->b_lblkno || 1521 (lblkno == root->b_lblkno && 1522 (xflags & BX_BKGRDMARKER) > (root->b_xflags & BX_BKGRDMARKER))) { 1523 if ((y = root->b_right) == NULL) 1524 break; 1525 if (lblkno > y->b_lblkno) { 1526 /* Rotate left. */ 1527 root->b_right = y->b_left; 1528 y->b_left = root; 1529 root = y; 1530 if ((y = root->b_right) == NULL) 1531 break; 1532 } 1533 /* Link into the new root's left tree. */ 1534 lefttreemax->b_right = root; 1535 lefttreemax = root; 1536 } else { 1537 break; 1538 } 1539 root = y; 1540 } 1541 /* Assemble the new root. */ 1542 lefttreemax->b_right = root->b_left; 1543 righttreemin->b_left = root->b_right; 1544 root->b_left = dummy.b_right; 1545 root->b_right = dummy.b_left; 1546 return (root); 1547 } 1548 1549 static void 1550 buf_vlist_remove(struct buf *bp) 1551 { 1552 struct buf *root; 1553 struct bufv *bv; 1554 1555 KASSERT(bp->b_bufobj != NULL, ("No b_bufobj %p", bp)); 1556 ASSERT_BO_LOCKED(bp->b_bufobj); 1557 KASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) != 1558 (BX_VNDIRTY|BX_VNCLEAN), 1559 ("buf_vlist_remove: Buf %p is on two lists", bp)); 1560 if (bp->b_xflags & BX_VNDIRTY) 1561 bv = &bp->b_bufobj->bo_dirty; 1562 else 1563 bv = &bp->b_bufobj->bo_clean; 1564 if (bp != bv->bv_root) { 1565 root = buf_splay(bp->b_lblkno, bp->b_xflags, bv->bv_root); 1566 KASSERT(root == bp, ("splay lookup failed in remove")); 1567 } 1568 if (bp->b_left == NULL) { 1569 root = bp->b_right; 1570 } else { 1571 root = buf_splay(bp->b_lblkno, bp->b_xflags, bp->b_left); 1572 root->b_right = bp->b_right; 1573 } 1574 bv->bv_root = root; 1575 TAILQ_REMOVE(&bv->bv_hd, bp, b_bobufs); 1576 bv->bv_cnt--; 1577 bp->b_xflags &= ~(BX_VNDIRTY | BX_VNCLEAN); 1578 } 1579 1580 /* 1581 * Add the buffer to the sorted clean or dirty block list using a 1582 * splay tree algorithm. 1583 * 1584 * NOTE: xflags is passed as a constant, optimizing this inline function! 1585 */ 1586 static void 1587 buf_vlist_add(struct buf *bp, struct bufobj *bo, b_xflags_t xflags) 1588 { 1589 struct buf *root; 1590 struct bufv *bv; 1591 1592 ASSERT_BO_LOCKED(bo); 1593 KASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) == 0, 1594 ("buf_vlist_add: Buf %p has existing xflags %d", bp, bp->b_xflags)); 1595 bp->b_xflags |= xflags; 1596 if (xflags & BX_VNDIRTY) 1597 bv = &bo->bo_dirty; 1598 else 1599 bv = &bo->bo_clean; 1600 1601 root = buf_splay(bp->b_lblkno, bp->b_xflags, bv->bv_root); 1602 if (root == NULL) { 1603 bp->b_left = NULL; 1604 bp->b_right = NULL; 1605 TAILQ_INSERT_TAIL(&bv->bv_hd, bp, b_bobufs); 1606 } else if (bp->b_lblkno < root->b_lblkno || 1607 (bp->b_lblkno == root->b_lblkno && 1608 (bp->b_xflags & BX_BKGRDMARKER) < (root->b_xflags & BX_BKGRDMARKER))) { 1609 bp->b_left = root->b_left; 1610 bp->b_right = root; 1611 root->b_left = NULL; 1612 TAILQ_INSERT_BEFORE(root, bp, b_bobufs); 1613 } else { 1614 bp->b_right = root->b_right; 1615 bp->b_left = root; 1616 root->b_right = NULL; 1617 TAILQ_INSERT_AFTER(&bv->bv_hd, root, bp, b_bobufs); 1618 } 1619 bv->bv_cnt++; 1620 bv->bv_root = bp; 1621 } 1622 1623 /* 1624 * Lookup a buffer using the splay tree. Note that we specifically avoid 1625 * shadow buffers used in background bitmap writes. 1626 * 1627 * This code isn't quite efficient as it could be because we are maintaining 1628 * two sorted lists and do not know which list the block resides in. 1629 * 1630 * During a "make buildworld" the desired buffer is found at one of 1631 * the roots more than 60% of the time. Thus, checking both roots 1632 * before performing either splay eliminates unnecessary splays on the 1633 * first tree splayed. 1634 */ 1635 struct buf * 1636 gbincore(struct bufobj *bo, daddr_t lblkno) 1637 { 1638 struct buf *bp; 1639 1640 ASSERT_BO_LOCKED(bo); 1641 if ((bp = bo->bo_clean.bv_root) != NULL && 1642 bp->b_lblkno == lblkno && !(bp->b_xflags & BX_BKGRDMARKER)) 1643 return (bp); 1644 if ((bp = bo->bo_dirty.bv_root) != NULL && 1645 bp->b_lblkno == lblkno && !(bp->b_xflags & BX_BKGRDMARKER)) 1646 return (bp); 1647 if ((bp = bo->bo_clean.bv_root) != NULL) { 1648 bo->bo_clean.bv_root = bp = buf_splay(lblkno, 0, bp); 1649 if (bp->b_lblkno == lblkno && !(bp->b_xflags & BX_BKGRDMARKER)) 1650 return (bp); 1651 } 1652 if ((bp = bo->bo_dirty.bv_root) != NULL) { 1653 bo->bo_dirty.bv_root = bp = buf_splay(lblkno, 0, bp); 1654 if (bp->b_lblkno == lblkno && !(bp->b_xflags & BX_BKGRDMARKER)) 1655 return (bp); 1656 } 1657 return (NULL); 1658 } 1659 1660 /* 1661 * Associate a buffer with a vnode. 1662 */ 1663 void 1664 bgetvp(struct vnode *vp, struct buf *bp) 1665 { 1666 struct bufobj *bo; 1667 1668 bo = &vp->v_bufobj; 1669 ASSERT_BO_LOCKED(bo); 1670 VNASSERT(bp->b_vp == NULL, bp->b_vp, ("bgetvp: not free")); 1671 1672 CTR3(KTR_BUF, "bgetvp(%p) vp %p flags %X", bp, vp, bp->b_flags); 1673 VNASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) == 0, vp, 1674 ("bgetvp: bp already attached! %p", bp)); 1675 1676 vhold(vp); 1677 bp->b_vp = vp; 1678 bp->b_bufobj = bo; 1679 /* 1680 * Insert onto list for new vnode. 1681 */ 1682 buf_vlist_add(bp, bo, BX_VNCLEAN); 1683 } 1684 1685 /* 1686 * Disassociate a buffer from a vnode. 1687 */ 1688 void 1689 brelvp(struct buf *bp) 1690 { 1691 struct bufobj *bo; 1692 struct vnode *vp; 1693 1694 CTR3(KTR_BUF, "brelvp(%p) vp %p flags %X", bp, bp->b_vp, bp->b_flags); 1695 KASSERT(bp->b_vp != NULL, ("brelvp: NULL")); 1696 1697 /* 1698 * Delete from old vnode list, if on one. 1699 */ 1700 vp = bp->b_vp; /* XXX */ 1701 bo = bp->b_bufobj; 1702 BO_LOCK(bo); 1703 if (bp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN)) 1704 buf_vlist_remove(bp); 1705 else 1706 panic("brelvp: Buffer %p not on queue.", bp); 1707 if ((bo->bo_flag & BO_ONWORKLST) && bo->bo_dirty.bv_cnt == 0) { 1708 bo->bo_flag &= ~BO_ONWORKLST; 1709 mtx_lock(&sync_mtx); 1710 LIST_REMOVE(bo, bo_synclist); 1711 syncer_worklist_len--; 1712 mtx_unlock(&sync_mtx); 1713 } 1714 bp->b_vp = NULL; 1715 bp->b_bufobj = NULL; 1716 BO_UNLOCK(bo); 1717 vdrop(vp); 1718 } 1719 1720 /* 1721 * Add an item to the syncer work queue. 1722 */ 1723 static void 1724 vn_syncer_add_to_worklist(struct bufobj *bo, int delay) 1725 { 1726 int slot; 1727 1728 ASSERT_BO_LOCKED(bo); 1729 1730 mtx_lock(&sync_mtx); 1731 if (bo->bo_flag & BO_ONWORKLST) 1732 LIST_REMOVE(bo, bo_synclist); 1733 else { 1734 bo->bo_flag |= BO_ONWORKLST; 1735 syncer_worklist_len++; 1736 } 1737 1738 if (delay > syncer_maxdelay - 2) 1739 delay = syncer_maxdelay - 2; 1740 slot = (syncer_delayno + delay) & syncer_mask; 1741 1742 LIST_INSERT_HEAD(&syncer_workitem_pending[slot], bo, bo_synclist); 1743 mtx_unlock(&sync_mtx); 1744 } 1745 1746 static int 1747 sysctl_vfs_worklist_len(SYSCTL_HANDLER_ARGS) 1748 { 1749 int error, len; 1750 1751 mtx_lock(&sync_mtx); 1752 len = syncer_worklist_len - sync_vnode_count; 1753 mtx_unlock(&sync_mtx); 1754 error = SYSCTL_OUT(req, &len, sizeof(len)); 1755 return (error); 1756 } 1757 1758 SYSCTL_PROC(_vfs, OID_AUTO, worklist_len, CTLTYPE_INT | CTLFLAG_RD, NULL, 0, 1759 sysctl_vfs_worklist_len, "I", "Syncer thread worklist length"); 1760 1761 static struct proc *updateproc; 1762 static void sched_sync(void); 1763 static struct kproc_desc up_kp = { 1764 "syncer", 1765 sched_sync, 1766 &updateproc 1767 }; 1768 SYSINIT(syncer, SI_SUB_KTHREAD_UPDATE, SI_ORDER_FIRST, kproc_start, &up_kp); 1769 1770 static int 1771 sync_vnode(struct synclist *slp, struct bufobj **bo, struct thread *td) 1772 { 1773 struct vnode *vp; 1774 struct mount *mp; 1775 1776 *bo = LIST_FIRST(slp); 1777 if (*bo == NULL) 1778 return (0); 1779 vp = (*bo)->__bo_vnode; /* XXX */ 1780 if (VOP_ISLOCKED(vp) != 0 || VI_TRYLOCK(vp) == 0) 1781 return (1); 1782 /* 1783 * We use vhold in case the vnode does not 1784 * successfully sync. vhold prevents the vnode from 1785 * going away when we unlock the sync_mtx so that 1786 * we can acquire the vnode interlock. 1787 */ 1788 vholdl(vp); 1789 mtx_unlock(&sync_mtx); 1790 VI_UNLOCK(vp); 1791 if (vn_start_write(vp, &mp, V_NOWAIT) != 0) { 1792 vdrop(vp); 1793 mtx_lock(&sync_mtx); 1794 return (*bo == LIST_FIRST(slp)); 1795 } 1796 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 1797 (void) VOP_FSYNC(vp, MNT_LAZY, td); 1798 VOP_UNLOCK(vp, 0); 1799 vn_finished_write(mp); 1800 BO_LOCK(*bo); 1801 if (((*bo)->bo_flag & BO_ONWORKLST) != 0) { 1802 /* 1803 * Put us back on the worklist. The worklist 1804 * routine will remove us from our current 1805 * position and then add us back in at a later 1806 * position. 1807 */ 1808 vn_syncer_add_to_worklist(*bo, syncdelay); 1809 } 1810 BO_UNLOCK(*bo); 1811 vdrop(vp); 1812 mtx_lock(&sync_mtx); 1813 return (0); 1814 } 1815 1816 /* 1817 * System filesystem synchronizer daemon. 1818 */ 1819 static void 1820 sched_sync(void) 1821 { 1822 struct synclist *next, *slp; 1823 struct bufobj *bo; 1824 long starttime; 1825 struct thread *td = curthread; 1826 int last_work_seen; 1827 int net_worklist_len; 1828 int syncer_final_iter; 1829 int first_printf; 1830 int error; 1831 1832 last_work_seen = 0; 1833 syncer_final_iter = 0; 1834 first_printf = 1; 1835 syncer_state = SYNCER_RUNNING; 1836 starttime = time_uptime; 1837 td->td_pflags |= TDP_NORUNNINGBUF; 1838 1839 EVENTHANDLER_REGISTER(shutdown_pre_sync, syncer_shutdown, td->td_proc, 1840 SHUTDOWN_PRI_LAST); 1841 1842 mtx_lock(&sync_mtx); 1843 for (;;) { 1844 if (syncer_state == SYNCER_FINAL_DELAY && 1845 syncer_final_iter == 0) { 1846 mtx_unlock(&sync_mtx); 1847 kproc_suspend_check(td->td_proc); 1848 mtx_lock(&sync_mtx); 1849 } 1850 net_worklist_len = syncer_worklist_len - sync_vnode_count; 1851 if (syncer_state != SYNCER_RUNNING && 1852 starttime != time_uptime) { 1853 if (first_printf) { 1854 printf("\nSyncing disks, vnodes remaining..."); 1855 first_printf = 0; 1856 } 1857 printf("%d ", net_worklist_len); 1858 } 1859 starttime = time_uptime; 1860 1861 /* 1862 * Push files whose dirty time has expired. Be careful 1863 * of interrupt race on slp queue. 1864 * 1865 * Skip over empty worklist slots when shutting down. 1866 */ 1867 do { 1868 slp = &syncer_workitem_pending[syncer_delayno]; 1869 syncer_delayno += 1; 1870 if (syncer_delayno == syncer_maxdelay) 1871 syncer_delayno = 0; 1872 next = &syncer_workitem_pending[syncer_delayno]; 1873 /* 1874 * If the worklist has wrapped since the 1875 * it was emptied of all but syncer vnodes, 1876 * switch to the FINAL_DELAY state and run 1877 * for one more second. 1878 */ 1879 if (syncer_state == SYNCER_SHUTTING_DOWN && 1880 net_worklist_len == 0 && 1881 last_work_seen == syncer_delayno) { 1882 syncer_state = SYNCER_FINAL_DELAY; 1883 syncer_final_iter = SYNCER_SHUTDOWN_SPEEDUP; 1884 } 1885 } while (syncer_state != SYNCER_RUNNING && LIST_EMPTY(slp) && 1886 syncer_worklist_len > 0); 1887 1888 /* 1889 * Keep track of the last time there was anything 1890 * on the worklist other than syncer vnodes. 1891 * Return to the SHUTTING_DOWN state if any 1892 * new work appears. 1893 */ 1894 if (net_worklist_len > 0 || syncer_state == SYNCER_RUNNING) 1895 last_work_seen = syncer_delayno; 1896 if (net_worklist_len > 0 && syncer_state == SYNCER_FINAL_DELAY) 1897 syncer_state = SYNCER_SHUTTING_DOWN; 1898 while (!LIST_EMPTY(slp)) { 1899 error = sync_vnode(slp, &bo, td); 1900 if (error == 1) { 1901 LIST_REMOVE(bo, bo_synclist); 1902 LIST_INSERT_HEAD(next, bo, bo_synclist); 1903 continue; 1904 } 1905 1906 if (first_printf == 0) 1907 wdog_kern_pat(WD_LASTVAL); 1908 1909 } 1910 if (syncer_state == SYNCER_FINAL_DELAY && syncer_final_iter > 0) 1911 syncer_final_iter--; 1912 /* 1913 * The variable rushjob allows the kernel to speed up the 1914 * processing of the filesystem syncer process. A rushjob 1915 * value of N tells the filesystem syncer to process the next 1916 * N seconds worth of work on its queue ASAP. Currently rushjob 1917 * is used by the soft update code to speed up the filesystem 1918 * syncer process when the incore state is getting so far 1919 * ahead of the disk that the kernel memory pool is being 1920 * threatened with exhaustion. 1921 */ 1922 if (rushjob > 0) { 1923 rushjob -= 1; 1924 continue; 1925 } 1926 /* 1927 * Just sleep for a short period of time between 1928 * iterations when shutting down to allow some I/O 1929 * to happen. 1930 * 1931 * If it has taken us less than a second to process the 1932 * current work, then wait. Otherwise start right over 1933 * again. We can still lose time if any single round 1934 * takes more than two seconds, but it does not really 1935 * matter as we are just trying to generally pace the 1936 * filesystem activity. 1937 */ 1938 if (syncer_state != SYNCER_RUNNING || 1939 time_uptime == starttime) { 1940 thread_lock(td); 1941 sched_prio(td, PPAUSE); 1942 thread_unlock(td); 1943 } 1944 if (syncer_state != SYNCER_RUNNING) 1945 cv_timedwait(&sync_wakeup, &sync_mtx, 1946 hz / SYNCER_SHUTDOWN_SPEEDUP); 1947 else if (time_uptime == starttime) 1948 cv_timedwait(&sync_wakeup, &sync_mtx, hz); 1949 } 1950 } 1951 1952 /* 1953 * Request the syncer daemon to speed up its work. 1954 * We never push it to speed up more than half of its 1955 * normal turn time, otherwise it could take over the cpu. 1956 */ 1957 int 1958 speedup_syncer(void) 1959 { 1960 int ret = 0; 1961 1962 mtx_lock(&sync_mtx); 1963 if (rushjob < syncdelay / 2) { 1964 rushjob += 1; 1965 stat_rush_requests += 1; 1966 ret = 1; 1967 } 1968 mtx_unlock(&sync_mtx); 1969 cv_broadcast(&sync_wakeup); 1970 return (ret); 1971 } 1972 1973 /* 1974 * Tell the syncer to speed up its work and run though its work 1975 * list several times, then tell it to shut down. 1976 */ 1977 static void 1978 syncer_shutdown(void *arg, int howto) 1979 { 1980 1981 if (howto & RB_NOSYNC) 1982 return; 1983 mtx_lock(&sync_mtx); 1984 syncer_state = SYNCER_SHUTTING_DOWN; 1985 rushjob = 0; 1986 mtx_unlock(&sync_mtx); 1987 cv_broadcast(&sync_wakeup); 1988 kproc_shutdown(arg, howto); 1989 } 1990 1991 /* 1992 * Reassign a buffer from one vnode to another. 1993 * Used to assign file specific control information 1994 * (indirect blocks) to the vnode to which they belong. 1995 */ 1996 void 1997 reassignbuf(struct buf *bp) 1998 { 1999 struct vnode *vp; 2000 struct bufobj *bo; 2001 int delay; 2002 #ifdef INVARIANTS 2003 struct bufv *bv; 2004 #endif 2005 2006 vp = bp->b_vp; 2007 bo = bp->b_bufobj; 2008 ++reassignbufcalls; 2009 2010 CTR3(KTR_BUF, "reassignbuf(%p) vp %p flags %X", 2011 bp, bp->b_vp, bp->b_flags); 2012 /* 2013 * B_PAGING flagged buffers cannot be reassigned because their vp 2014 * is not fully linked in. 2015 */ 2016 if (bp->b_flags & B_PAGING) 2017 panic("cannot reassign paging buffer"); 2018 2019 /* 2020 * Delete from old vnode list, if on one. 2021 */ 2022 BO_LOCK(bo); 2023 if (bp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN)) 2024 buf_vlist_remove(bp); 2025 else 2026 panic("reassignbuf: Buffer %p not on queue.", bp); 2027 /* 2028 * If dirty, put on list of dirty buffers; otherwise insert onto list 2029 * of clean buffers. 2030 */ 2031 if (bp->b_flags & B_DELWRI) { 2032 if ((bo->bo_flag & BO_ONWORKLST) == 0) { 2033 switch (vp->v_type) { 2034 case VDIR: 2035 delay = dirdelay; 2036 break; 2037 case VCHR: 2038 delay = metadelay; 2039 break; 2040 default: 2041 delay = filedelay; 2042 } 2043 vn_syncer_add_to_worklist(bo, delay); 2044 } 2045 buf_vlist_add(bp, bo, BX_VNDIRTY); 2046 } else { 2047 buf_vlist_add(bp, bo, BX_VNCLEAN); 2048 2049 if ((bo->bo_flag & BO_ONWORKLST) && bo->bo_dirty.bv_cnt == 0) { 2050 mtx_lock(&sync_mtx); 2051 LIST_REMOVE(bo, bo_synclist); 2052 syncer_worklist_len--; 2053 mtx_unlock(&sync_mtx); 2054 bo->bo_flag &= ~BO_ONWORKLST; 2055 } 2056 } 2057 #ifdef INVARIANTS 2058 bv = &bo->bo_clean; 2059 bp = TAILQ_FIRST(&bv->bv_hd); 2060 KASSERT(bp == NULL || bp->b_bufobj == bo, 2061 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 2062 bp = TAILQ_LAST(&bv->bv_hd, buflists); 2063 KASSERT(bp == NULL || bp->b_bufobj == bo, 2064 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 2065 bv = &bo->bo_dirty; 2066 bp = TAILQ_FIRST(&bv->bv_hd); 2067 KASSERT(bp == NULL || bp->b_bufobj == bo, 2068 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 2069 bp = TAILQ_LAST(&bv->bv_hd, buflists); 2070 KASSERT(bp == NULL || bp->b_bufobj == bo, 2071 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 2072 #endif 2073 BO_UNLOCK(bo); 2074 } 2075 2076 /* 2077 * Increment the use and hold counts on the vnode, taking care to reference 2078 * the driver's usecount if this is a chardev. The vholdl() will remove 2079 * the vnode from the free list if it is presently free. Requires the 2080 * vnode interlock and returns with it held. 2081 */ 2082 static void 2083 v_incr_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 vholdl(vp); 2094 } 2095 2096 /* 2097 * Turn a holdcnt into a use+holdcnt such that only one call to 2098 * v_decr_usecount is needed. 2099 */ 2100 static void 2101 v_upgrade_usecount(struct vnode *vp) 2102 { 2103 2104 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2105 vp->v_usecount++; 2106 if (vp->v_type == VCHR && vp->v_rdev != NULL) { 2107 dev_lock(); 2108 vp->v_rdev->si_usecount++; 2109 dev_unlock(); 2110 } 2111 } 2112 2113 /* 2114 * Decrement the vnode use and hold count along with the driver's usecount 2115 * if this is a chardev. The vdropl() below releases the vnode interlock 2116 * as it may free the vnode. 2117 */ 2118 static void 2119 v_decr_usecount(struct vnode *vp) 2120 { 2121 2122 ASSERT_VI_LOCKED(vp, __FUNCTION__); 2123 VNASSERT(vp->v_usecount > 0, vp, 2124 ("v_decr_usecount: negative usecount")); 2125 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2126 vp->v_usecount--; 2127 if (vp->v_type == VCHR && vp->v_rdev != NULL) { 2128 dev_lock(); 2129 vp->v_rdev->si_usecount--; 2130 dev_unlock(); 2131 } 2132 vdropl(vp); 2133 } 2134 2135 /* 2136 * Decrement only the use count and driver use count. This is intended to 2137 * be paired with a follow on vdropl() to release the remaining hold count. 2138 * In this way we may vgone() a vnode with a 0 usecount without risk of 2139 * having it end up on a free list because the hold count is kept above 0. 2140 */ 2141 static void 2142 v_decr_useonly(struct vnode *vp) 2143 { 2144 2145 ASSERT_VI_LOCKED(vp, __FUNCTION__); 2146 VNASSERT(vp->v_usecount > 0, vp, 2147 ("v_decr_useonly: negative usecount")); 2148 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2149 vp->v_usecount--; 2150 if (vp->v_type == VCHR && vp->v_rdev != NULL) { 2151 dev_lock(); 2152 vp->v_rdev->si_usecount--; 2153 dev_unlock(); 2154 } 2155 } 2156 2157 /* 2158 * Grab a particular vnode from the free list, increment its 2159 * reference count and lock it. VI_DOOMED is set if the vnode 2160 * is being destroyed. Only callers who specify LK_RETRY will 2161 * see doomed vnodes. If inactive processing was delayed in 2162 * vput try to do it here. 2163 */ 2164 int 2165 vget(struct vnode *vp, int flags, struct thread *td) 2166 { 2167 int error; 2168 2169 error = 0; 2170 VNASSERT((flags & LK_TYPE_MASK) != 0, vp, 2171 ("vget: invalid lock operation")); 2172 CTR3(KTR_VFS, "%s: vp %p with flags %d", __func__, vp, flags); 2173 2174 if ((flags & LK_INTERLOCK) == 0) 2175 VI_LOCK(vp); 2176 vholdl(vp); 2177 if ((error = vn_lock(vp, flags | LK_INTERLOCK)) != 0) { 2178 vdrop(vp); 2179 CTR2(KTR_VFS, "%s: impossible to lock vnode %p", __func__, 2180 vp); 2181 return (error); 2182 } 2183 if (vp->v_iflag & VI_DOOMED && (flags & LK_RETRY) == 0) 2184 panic("vget: vn_lock failed to return ENOENT\n"); 2185 VI_LOCK(vp); 2186 /* Upgrade our holdcnt to a usecount. */ 2187 v_upgrade_usecount(vp); 2188 /* 2189 * We don't guarantee that any particular close will 2190 * trigger inactive processing so just make a best effort 2191 * here at preventing a reference to a removed file. If 2192 * we don't succeed no harm is done. 2193 */ 2194 if (vp->v_iflag & VI_OWEINACT) { 2195 if (VOP_ISLOCKED(vp) == LK_EXCLUSIVE && 2196 (flags & LK_NOWAIT) == 0) 2197 vinactive(vp, td); 2198 vp->v_iflag &= ~VI_OWEINACT; 2199 } 2200 VI_UNLOCK(vp); 2201 return (0); 2202 } 2203 2204 /* 2205 * Increase the reference count of a vnode. 2206 */ 2207 void 2208 vref(struct vnode *vp) 2209 { 2210 2211 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2212 VI_LOCK(vp); 2213 v_incr_usecount(vp); 2214 VI_UNLOCK(vp); 2215 } 2216 2217 /* 2218 * Return reference count of a vnode. 2219 * 2220 * The results of this call are only guaranteed when some mechanism other 2221 * than the VI lock is used to stop other processes from gaining references 2222 * to the vnode. This may be the case if the caller holds the only reference. 2223 * This is also useful when stale data is acceptable as race conditions may 2224 * be accounted for by some other means. 2225 */ 2226 int 2227 vrefcnt(struct vnode *vp) 2228 { 2229 int usecnt; 2230 2231 VI_LOCK(vp); 2232 usecnt = vp->v_usecount; 2233 VI_UNLOCK(vp); 2234 2235 return (usecnt); 2236 } 2237 2238 #define VPUTX_VRELE 1 2239 #define VPUTX_VPUT 2 2240 #define VPUTX_VUNREF 3 2241 2242 static void 2243 vputx(struct vnode *vp, int func) 2244 { 2245 int error; 2246 2247 KASSERT(vp != NULL, ("vputx: null vp")); 2248 if (func == VPUTX_VUNREF) 2249 ASSERT_VOP_LOCKED(vp, "vunref"); 2250 else if (func == VPUTX_VPUT) 2251 ASSERT_VOP_LOCKED(vp, "vput"); 2252 else 2253 KASSERT(func == VPUTX_VRELE, ("vputx: wrong func")); 2254 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2255 VI_LOCK(vp); 2256 2257 /* Skip this v_writecount check if we're going to panic below. */ 2258 VNASSERT(vp->v_writecount < vp->v_usecount || vp->v_usecount < 1, vp, 2259 ("vputx: missed vn_close")); 2260 error = 0; 2261 2262 if (vp->v_usecount > 1 || ((vp->v_iflag & VI_DOINGINACT) && 2263 vp->v_usecount == 1)) { 2264 if (func == VPUTX_VPUT) 2265 VOP_UNLOCK(vp, 0); 2266 v_decr_usecount(vp); 2267 return; 2268 } 2269 2270 if (vp->v_usecount != 1) { 2271 vprint("vputx: negative ref count", vp); 2272 panic("vputx: negative ref cnt"); 2273 } 2274 CTR2(KTR_VFS, "%s: return vnode %p to the freelist", __func__, vp); 2275 /* 2276 * We want to hold the vnode until the inactive finishes to 2277 * prevent vgone() races. We drop the use count here and the 2278 * hold count below when we're done. 2279 */ 2280 v_decr_useonly(vp); 2281 /* 2282 * We must call VOP_INACTIVE with the node locked. Mark 2283 * as VI_DOINGINACT to avoid recursion. 2284 */ 2285 vp->v_iflag |= VI_OWEINACT; 2286 switch (func) { 2287 case VPUTX_VRELE: 2288 error = vn_lock(vp, LK_EXCLUSIVE | LK_INTERLOCK); 2289 VI_LOCK(vp); 2290 break; 2291 case VPUTX_VPUT: 2292 if (VOP_ISLOCKED(vp) != LK_EXCLUSIVE) { 2293 error = VOP_LOCK(vp, LK_UPGRADE | LK_INTERLOCK | 2294 LK_NOWAIT); 2295 VI_LOCK(vp); 2296 } 2297 break; 2298 case VPUTX_VUNREF: 2299 if (VOP_ISLOCKED(vp) != LK_EXCLUSIVE) 2300 error = EBUSY; 2301 break; 2302 } 2303 if (vp->v_usecount > 0) 2304 vp->v_iflag &= ~VI_OWEINACT; 2305 if (error == 0) { 2306 if (vp->v_iflag & VI_OWEINACT) 2307 vinactive(vp, curthread); 2308 if (func != VPUTX_VUNREF) 2309 VOP_UNLOCK(vp, 0); 2310 } 2311 vdropl(vp); 2312 } 2313 2314 /* 2315 * Vnode put/release. 2316 * If count drops to zero, call inactive routine and return to freelist. 2317 */ 2318 void 2319 vrele(struct vnode *vp) 2320 { 2321 2322 vputx(vp, VPUTX_VRELE); 2323 } 2324 2325 /* 2326 * Release an already locked vnode. This give the same effects as 2327 * unlock+vrele(), but takes less time and avoids releasing and 2328 * re-aquiring the lock (as vrele() acquires the lock internally.) 2329 */ 2330 void 2331 vput(struct vnode *vp) 2332 { 2333 2334 vputx(vp, VPUTX_VPUT); 2335 } 2336 2337 /* 2338 * Release an exclusively locked vnode. Do not unlock the vnode lock. 2339 */ 2340 void 2341 vunref(struct vnode *vp) 2342 { 2343 2344 vputx(vp, VPUTX_VUNREF); 2345 } 2346 2347 /* 2348 * Somebody doesn't want the vnode recycled. 2349 */ 2350 void 2351 vhold(struct vnode *vp) 2352 { 2353 2354 VI_LOCK(vp); 2355 vholdl(vp); 2356 VI_UNLOCK(vp); 2357 } 2358 2359 /* 2360 * Increase the hold count and activate if this is the first reference. 2361 */ 2362 void 2363 vholdl(struct vnode *vp) 2364 { 2365 struct mount *mp; 2366 2367 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2368 vp->v_holdcnt++; 2369 if (!VSHOULDBUSY(vp)) 2370 return; 2371 ASSERT_VI_LOCKED(vp, "vholdl"); 2372 VNASSERT((vp->v_iflag & VI_FREE) != 0, vp, ("vnode not free")); 2373 VNASSERT(vp->v_op != NULL, vp, ("vholdl: vnode already reclaimed.")); 2374 /* 2375 * Remove a vnode from the free list, mark it as in use, 2376 * and put it on the active list. 2377 */ 2378 mtx_lock(&vnode_free_list_mtx); 2379 TAILQ_REMOVE(&vnode_free_list, vp, v_actfreelist); 2380 freevnodes--; 2381 vp->v_iflag &= ~(VI_FREE|VI_AGE); 2382 KASSERT((vp->v_iflag & VI_ACTIVE) == 0, 2383 ("Activating already active vnode")); 2384 vp->v_iflag |= VI_ACTIVE; 2385 mp = vp->v_mount; 2386 TAILQ_INSERT_HEAD(&mp->mnt_activevnodelist, vp, v_actfreelist); 2387 mp->mnt_activevnodelistsize++; 2388 mtx_unlock(&vnode_free_list_mtx); 2389 } 2390 2391 /* 2392 * Note that there is one less who cares about this vnode. 2393 * vdrop() is the opposite of vhold(). 2394 */ 2395 void 2396 vdrop(struct vnode *vp) 2397 { 2398 2399 VI_LOCK(vp); 2400 vdropl(vp); 2401 } 2402 2403 /* 2404 * Drop the hold count of the vnode. If this is the last reference to 2405 * the vnode we place it on the free list unless it has been vgone'd 2406 * (marked VI_DOOMED) in which case we will free it. 2407 */ 2408 void 2409 vdropl(struct vnode *vp) 2410 { 2411 struct bufobj *bo; 2412 struct mount *mp; 2413 int active; 2414 2415 ASSERT_VI_LOCKED(vp, "vdropl"); 2416 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2417 if (vp->v_holdcnt <= 0) 2418 panic("vdrop: holdcnt %d", vp->v_holdcnt); 2419 vp->v_holdcnt--; 2420 if (vp->v_holdcnt > 0) { 2421 VI_UNLOCK(vp); 2422 return; 2423 } 2424 if ((vp->v_iflag & VI_DOOMED) == 0) { 2425 /* 2426 * Mark a vnode as free: remove it from its active list 2427 * and put it up for recycling on the freelist. 2428 */ 2429 VNASSERT(vp->v_op != NULL, vp, 2430 ("vdropl: vnode already reclaimed.")); 2431 VNASSERT((vp->v_iflag & VI_FREE) == 0, vp, 2432 ("vnode already free")); 2433 VNASSERT(VSHOULDFREE(vp), vp, 2434 ("vdropl: freeing when we shouldn't")); 2435 active = vp->v_iflag & VI_ACTIVE; 2436 vp->v_iflag &= ~VI_ACTIVE; 2437 mp = vp->v_mount; 2438 mtx_lock(&vnode_free_list_mtx); 2439 if (active) { 2440 TAILQ_REMOVE(&mp->mnt_activevnodelist, vp, 2441 v_actfreelist); 2442 mp->mnt_activevnodelistsize--; 2443 } 2444 if (vp->v_iflag & VI_AGE) { 2445 TAILQ_INSERT_HEAD(&vnode_free_list, vp, v_actfreelist); 2446 } else { 2447 TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_actfreelist); 2448 } 2449 freevnodes++; 2450 vp->v_iflag &= ~VI_AGE; 2451 vp->v_iflag |= VI_FREE; 2452 mtx_unlock(&vnode_free_list_mtx); 2453 VI_UNLOCK(vp); 2454 return; 2455 } 2456 /* 2457 * The vnode has been marked for destruction, so free it. 2458 */ 2459 CTR2(KTR_VFS, "%s: destroying the vnode %p", __func__, vp); 2460 mtx_lock(&vnode_free_list_mtx); 2461 numvnodes--; 2462 mtx_unlock(&vnode_free_list_mtx); 2463 bo = &vp->v_bufobj; 2464 VNASSERT((vp->v_iflag & VI_FREE) == 0, vp, 2465 ("cleaned vnode still on the free list.")); 2466 VNASSERT(vp->v_data == NULL, vp, ("cleaned vnode isn't")); 2467 VNASSERT(vp->v_holdcnt == 0, vp, ("Non-zero hold count")); 2468 VNASSERT(vp->v_usecount == 0, vp, ("Non-zero use count")); 2469 VNASSERT(vp->v_writecount == 0, vp, ("Non-zero write count")); 2470 VNASSERT(bo->bo_numoutput == 0, vp, ("Clean vnode has pending I/O's")); 2471 VNASSERT(bo->bo_clean.bv_cnt == 0, vp, ("cleanbufcnt not 0")); 2472 VNASSERT(bo->bo_clean.bv_root == NULL, vp, ("cleanblkroot not NULL")); 2473 VNASSERT(bo->bo_dirty.bv_cnt == 0, vp, ("dirtybufcnt not 0")); 2474 VNASSERT(bo->bo_dirty.bv_root == NULL, vp, ("dirtyblkroot not NULL")); 2475 VNASSERT(TAILQ_EMPTY(&vp->v_cache_dst), vp, ("vp has namecache dst")); 2476 VNASSERT(LIST_EMPTY(&vp->v_cache_src), vp, ("vp has namecache src")); 2477 VNASSERT(vp->v_cache_dd == NULL, vp, ("vp has namecache for ..")); 2478 VI_UNLOCK(vp); 2479 #ifdef MAC 2480 mac_vnode_destroy(vp); 2481 #endif 2482 if (vp->v_pollinfo != NULL) 2483 destroy_vpollinfo(vp->v_pollinfo); 2484 #ifdef INVARIANTS 2485 /* XXX Elsewhere we detect an already freed vnode via NULL v_op. */ 2486 vp->v_op = NULL; 2487 #endif 2488 rangelock_destroy(&vp->v_rl); 2489 lockdestroy(vp->v_vnlock); 2490 mtx_destroy(&vp->v_interlock); 2491 mtx_destroy(BO_MTX(bo)); 2492 uma_zfree(vnode_zone, vp); 2493 } 2494 2495 /* 2496 * Call VOP_INACTIVE on the vnode and manage the DOINGINACT and OWEINACT 2497 * flags. DOINGINACT prevents us from recursing in calls to vinactive. 2498 * OWEINACT tracks whether a vnode missed a call to inactive due to a 2499 * failed lock upgrade. 2500 */ 2501 void 2502 vinactive(struct vnode *vp, struct thread *td) 2503 { 2504 struct vm_object *obj; 2505 2506 ASSERT_VOP_ELOCKED(vp, "vinactive"); 2507 ASSERT_VI_LOCKED(vp, "vinactive"); 2508 VNASSERT((vp->v_iflag & VI_DOINGINACT) == 0, vp, 2509 ("vinactive: recursed on VI_DOINGINACT")); 2510 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2511 vp->v_iflag |= VI_DOINGINACT; 2512 vp->v_iflag &= ~VI_OWEINACT; 2513 VI_UNLOCK(vp); 2514 /* 2515 * Before moving off the active list, we must be sure that any 2516 * modified pages are on the vnode's dirty list since these will 2517 * no longer be checked once the vnode is on the inactive list. 2518 * Because the vnode vm object keeps a hold reference on the vnode 2519 * if there is at least one resident non-cached page, the vnode 2520 * cannot leave the active list without the page cleanup done. 2521 */ 2522 obj = vp->v_object; 2523 if (obj != NULL && (obj->flags & OBJ_MIGHTBEDIRTY) != 0) { 2524 VM_OBJECT_WLOCK(obj); 2525 vm_object_page_clean(obj, 0, 0, OBJPC_NOSYNC); 2526 VM_OBJECT_WUNLOCK(obj); 2527 } 2528 VOP_INACTIVE(vp, td); 2529 VI_LOCK(vp); 2530 VNASSERT(vp->v_iflag & VI_DOINGINACT, vp, 2531 ("vinactive: lost VI_DOINGINACT")); 2532 vp->v_iflag &= ~VI_DOINGINACT; 2533 } 2534 2535 /* 2536 * Remove any vnodes in the vnode table belonging to mount point mp. 2537 * 2538 * If FORCECLOSE is not specified, there should not be any active ones, 2539 * return error if any are found (nb: this is a user error, not a 2540 * system error). If FORCECLOSE is specified, detach any active vnodes 2541 * that are found. 2542 * 2543 * If WRITECLOSE is set, only flush out regular file vnodes open for 2544 * writing. 2545 * 2546 * SKIPSYSTEM causes any vnodes marked VV_SYSTEM to be skipped. 2547 * 2548 * `rootrefs' specifies the base reference count for the root vnode 2549 * of this filesystem. The root vnode is considered busy if its 2550 * v_usecount exceeds this value. On a successful return, vflush(, td) 2551 * will call vrele() on the root vnode exactly rootrefs times. 2552 * If the SKIPSYSTEM or WRITECLOSE flags are specified, rootrefs must 2553 * be zero. 2554 */ 2555 #ifdef DIAGNOSTIC 2556 static int busyprt = 0; /* print out busy vnodes */ 2557 SYSCTL_INT(_debug, OID_AUTO, busyprt, CTLFLAG_RW, &busyprt, 0, "Print out busy vnodes"); 2558 #endif 2559 2560 int 2561 vflush(struct mount *mp, int rootrefs, int flags, struct thread *td) 2562 { 2563 struct vnode *vp, *mvp, *rootvp = NULL; 2564 struct vattr vattr; 2565 int busy = 0, error; 2566 2567 CTR4(KTR_VFS, "%s: mp %p with rootrefs %d and flags %d", __func__, mp, 2568 rootrefs, flags); 2569 if (rootrefs > 0) { 2570 KASSERT((flags & (SKIPSYSTEM | WRITECLOSE)) == 0, 2571 ("vflush: bad args")); 2572 /* 2573 * Get the filesystem root vnode. We can vput() it 2574 * immediately, since with rootrefs > 0, it won't go away. 2575 */ 2576 if ((error = VFS_ROOT(mp, LK_EXCLUSIVE, &rootvp)) != 0) { 2577 CTR2(KTR_VFS, "%s: vfs_root lookup failed with %d", 2578 __func__, error); 2579 return (error); 2580 } 2581 vput(rootvp); 2582 } 2583 loop: 2584 MNT_VNODE_FOREACH_ALL(vp, mp, mvp) { 2585 vholdl(vp); 2586 error = vn_lock(vp, LK_INTERLOCK | LK_EXCLUSIVE); 2587 if (error) { 2588 vdrop(vp); 2589 MNT_VNODE_FOREACH_ALL_ABORT(mp, mvp); 2590 goto loop; 2591 } 2592 /* 2593 * Skip over a vnodes marked VV_SYSTEM. 2594 */ 2595 if ((flags & SKIPSYSTEM) && (vp->v_vflag & VV_SYSTEM)) { 2596 VOP_UNLOCK(vp, 0); 2597 vdrop(vp); 2598 continue; 2599 } 2600 /* 2601 * If WRITECLOSE is set, flush out unlinked but still open 2602 * files (even if open only for reading) and regular file 2603 * vnodes open for writing. 2604 */ 2605 if (flags & WRITECLOSE) { 2606 if (vp->v_object != NULL) { 2607 VM_OBJECT_WLOCK(vp->v_object); 2608 vm_object_page_clean(vp->v_object, 0, 0, 0); 2609 VM_OBJECT_WUNLOCK(vp->v_object); 2610 } 2611 error = VOP_FSYNC(vp, MNT_WAIT, td); 2612 if (error != 0) { 2613 VOP_UNLOCK(vp, 0); 2614 vdrop(vp); 2615 MNT_VNODE_FOREACH_ALL_ABORT(mp, mvp); 2616 return (error); 2617 } 2618 error = VOP_GETATTR(vp, &vattr, td->td_ucred); 2619 VI_LOCK(vp); 2620 2621 if ((vp->v_type == VNON || 2622 (error == 0 && vattr.va_nlink > 0)) && 2623 (vp->v_writecount == 0 || vp->v_type != VREG)) { 2624 VOP_UNLOCK(vp, 0); 2625 vdropl(vp); 2626 continue; 2627 } 2628 } else 2629 VI_LOCK(vp); 2630 /* 2631 * With v_usecount == 0, all we need to do is clear out the 2632 * vnode data structures and we are done. 2633 * 2634 * If FORCECLOSE is set, forcibly close the vnode. 2635 */ 2636 if (vp->v_usecount == 0 || (flags & FORCECLOSE)) { 2637 VNASSERT(vp->v_usecount == 0 || 2638 (vp->v_type != VCHR && vp->v_type != VBLK), vp, 2639 ("device VNODE %p is FORCECLOSED", vp)); 2640 vgonel(vp); 2641 } else { 2642 busy++; 2643 #ifdef DIAGNOSTIC 2644 if (busyprt) 2645 vprint("vflush: busy vnode", vp); 2646 #endif 2647 } 2648 VOP_UNLOCK(vp, 0); 2649 vdropl(vp); 2650 } 2651 if (rootrefs > 0 && (flags & FORCECLOSE) == 0) { 2652 /* 2653 * If just the root vnode is busy, and if its refcount 2654 * is equal to `rootrefs', then go ahead and kill it. 2655 */ 2656 VI_LOCK(rootvp); 2657 KASSERT(busy > 0, ("vflush: not busy")); 2658 VNASSERT(rootvp->v_usecount >= rootrefs, rootvp, 2659 ("vflush: usecount %d < rootrefs %d", 2660 rootvp->v_usecount, rootrefs)); 2661 if (busy == 1 && rootvp->v_usecount == rootrefs) { 2662 VOP_LOCK(rootvp, LK_EXCLUSIVE|LK_INTERLOCK); 2663 vgone(rootvp); 2664 VOP_UNLOCK(rootvp, 0); 2665 busy = 0; 2666 } else 2667 VI_UNLOCK(rootvp); 2668 } 2669 if (busy) { 2670 CTR2(KTR_VFS, "%s: failing as %d vnodes are busy", __func__, 2671 busy); 2672 return (EBUSY); 2673 } 2674 for (; rootrefs > 0; rootrefs--) 2675 vrele(rootvp); 2676 return (0); 2677 } 2678 2679 /* 2680 * Recycle an unused vnode to the front of the free list. 2681 */ 2682 int 2683 vrecycle(struct vnode *vp) 2684 { 2685 int recycled; 2686 2687 ASSERT_VOP_ELOCKED(vp, "vrecycle"); 2688 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2689 recycled = 0; 2690 VI_LOCK(vp); 2691 if (vp->v_usecount == 0) { 2692 recycled = 1; 2693 vgonel(vp); 2694 } 2695 VI_UNLOCK(vp); 2696 return (recycled); 2697 } 2698 2699 /* 2700 * Eliminate all activity associated with a vnode 2701 * in preparation for reuse. 2702 */ 2703 void 2704 vgone(struct vnode *vp) 2705 { 2706 VI_LOCK(vp); 2707 vgonel(vp); 2708 VI_UNLOCK(vp); 2709 } 2710 2711 static void 2712 vgonel_reclaim_lowervp_vfs(struct mount *mp __unused, 2713 struct vnode *lowervp __unused) 2714 { 2715 } 2716 2717 /* 2718 * Notify upper mounts about reclaimed vnode. 2719 */ 2720 static void 2721 vgonel_reclaim_lowervp(struct vnode *vp) 2722 { 2723 static struct vfsops vgonel_vfsops = { 2724 .vfs_reclaim_lowervp = vgonel_reclaim_lowervp_vfs 2725 }; 2726 struct mount *mp, *ump, *mmp; 2727 2728 mp = vp->v_mount; 2729 if (mp == NULL) 2730 return; 2731 2732 MNT_ILOCK(mp); 2733 if (TAILQ_EMPTY(&mp->mnt_uppers)) 2734 goto unlock; 2735 MNT_IUNLOCK(mp); 2736 mmp = malloc(sizeof(struct mount), M_TEMP, M_WAITOK | M_ZERO); 2737 mmp->mnt_op = &vgonel_vfsops; 2738 mmp->mnt_kern_flag |= MNTK_MARKER; 2739 MNT_ILOCK(mp); 2740 mp->mnt_kern_flag |= MNTK_VGONE_UPPER; 2741 for (ump = TAILQ_FIRST(&mp->mnt_uppers); ump != NULL;) { 2742 if ((ump->mnt_kern_flag & MNTK_MARKER) != 0) { 2743 ump = TAILQ_NEXT(ump, mnt_upper_link); 2744 continue; 2745 } 2746 TAILQ_INSERT_AFTER(&mp->mnt_uppers, ump, mmp, mnt_upper_link); 2747 MNT_IUNLOCK(mp); 2748 VFS_RECLAIM_LOWERVP(ump, vp); 2749 MNT_ILOCK(mp); 2750 ump = TAILQ_NEXT(mmp, mnt_upper_link); 2751 TAILQ_REMOVE(&mp->mnt_uppers, mmp, mnt_upper_link); 2752 } 2753 free(mmp, M_TEMP); 2754 mp->mnt_kern_flag &= ~MNTK_VGONE_UPPER; 2755 if ((mp->mnt_kern_flag & MNTK_VGONE_WAITER) != 0) { 2756 mp->mnt_kern_flag &= ~MNTK_VGONE_WAITER; 2757 wakeup(&mp->mnt_uppers); 2758 } 2759 unlock: 2760 MNT_IUNLOCK(mp); 2761 } 2762 2763 /* 2764 * vgone, with the vp interlock held. 2765 */ 2766 void 2767 vgonel(struct vnode *vp) 2768 { 2769 struct thread *td; 2770 int oweinact; 2771 int active; 2772 struct mount *mp; 2773 2774 ASSERT_VOP_ELOCKED(vp, "vgonel"); 2775 ASSERT_VI_LOCKED(vp, "vgonel"); 2776 VNASSERT(vp->v_holdcnt, vp, 2777 ("vgonel: vp %p has no reference.", vp)); 2778 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2779 td = curthread; 2780 2781 /* 2782 * Don't vgonel if we're already doomed. 2783 */ 2784 if (vp->v_iflag & VI_DOOMED) 2785 return; 2786 vp->v_iflag |= VI_DOOMED; 2787 2788 /* 2789 * Check to see if the vnode is in use. If so, we have to call 2790 * VOP_CLOSE() and VOP_INACTIVE(). 2791 */ 2792 active = vp->v_usecount; 2793 oweinact = (vp->v_iflag & VI_OWEINACT); 2794 VI_UNLOCK(vp); 2795 vgonel_reclaim_lowervp(vp); 2796 2797 /* 2798 * Clean out any buffers associated with the vnode. 2799 * If the flush fails, just toss the buffers. 2800 */ 2801 mp = NULL; 2802 if (!TAILQ_EMPTY(&vp->v_bufobj.bo_dirty.bv_hd)) 2803 (void) vn_start_secondary_write(vp, &mp, V_WAIT); 2804 if (vinvalbuf(vp, V_SAVE, 0, 0) != 0) 2805 vinvalbuf(vp, 0, 0, 0); 2806 2807 /* 2808 * If purging an active vnode, it must be closed and 2809 * deactivated before being reclaimed. 2810 */ 2811 if (active) 2812 VOP_CLOSE(vp, FNONBLOCK, NOCRED, td); 2813 if (oweinact || active) { 2814 VI_LOCK(vp); 2815 if ((vp->v_iflag & VI_DOINGINACT) == 0) 2816 vinactive(vp, td); 2817 VI_UNLOCK(vp); 2818 } 2819 if (vp->v_type == VSOCK) 2820 vfs_unp_reclaim(vp); 2821 /* 2822 * Reclaim the vnode. 2823 */ 2824 if (VOP_RECLAIM(vp, td)) 2825 panic("vgone: cannot reclaim"); 2826 if (mp != NULL) 2827 vn_finished_secondary_write(mp); 2828 VNASSERT(vp->v_object == NULL, vp, 2829 ("vop_reclaim left v_object vp=%p, tag=%s", vp, vp->v_tag)); 2830 /* 2831 * Clear the advisory locks and wake up waiting threads. 2832 */ 2833 (void)VOP_ADVLOCKPURGE(vp); 2834 /* 2835 * Delete from old mount point vnode list. 2836 */ 2837 delmntque(vp); 2838 cache_purge(vp); 2839 /* 2840 * Done with purge, reset to the standard lock and invalidate 2841 * the vnode. 2842 */ 2843 VI_LOCK(vp); 2844 vp->v_vnlock = &vp->v_lock; 2845 vp->v_op = &dead_vnodeops; 2846 vp->v_tag = "none"; 2847 vp->v_type = VBAD; 2848 } 2849 2850 /* 2851 * Calculate the total number of references to a special device. 2852 */ 2853 int 2854 vcount(struct vnode *vp) 2855 { 2856 int count; 2857 2858 dev_lock(); 2859 count = vp->v_rdev->si_usecount; 2860 dev_unlock(); 2861 return (count); 2862 } 2863 2864 /* 2865 * Same as above, but using the struct cdev *as argument 2866 */ 2867 int 2868 count_dev(struct cdev *dev) 2869 { 2870 int count; 2871 2872 dev_lock(); 2873 count = dev->si_usecount; 2874 dev_unlock(); 2875 return(count); 2876 } 2877 2878 /* 2879 * Print out a description of a vnode. 2880 */ 2881 static char *typename[] = 2882 {"VNON", "VREG", "VDIR", "VBLK", "VCHR", "VLNK", "VSOCK", "VFIFO", "VBAD", 2883 "VMARKER"}; 2884 2885 void 2886 vn_printf(struct vnode *vp, const char *fmt, ...) 2887 { 2888 va_list ap; 2889 char buf[256], buf2[16]; 2890 u_long flags; 2891 2892 va_start(ap, fmt); 2893 vprintf(fmt, ap); 2894 va_end(ap); 2895 printf("%p: ", (void *)vp); 2896 printf("tag %s, type %s\n", vp->v_tag, typename[vp->v_type]); 2897 printf(" usecount %d, writecount %d, refcount %d mountedhere %p\n", 2898 vp->v_usecount, vp->v_writecount, vp->v_holdcnt, vp->v_mountedhere); 2899 buf[0] = '\0'; 2900 buf[1] = '\0'; 2901 if (vp->v_vflag & VV_ROOT) 2902 strlcat(buf, "|VV_ROOT", sizeof(buf)); 2903 if (vp->v_vflag & VV_ISTTY) 2904 strlcat(buf, "|VV_ISTTY", sizeof(buf)); 2905 if (vp->v_vflag & VV_NOSYNC) 2906 strlcat(buf, "|VV_NOSYNC", sizeof(buf)); 2907 if (vp->v_vflag & VV_ETERNALDEV) 2908 strlcat(buf, "|VV_ETERNALDEV", sizeof(buf)); 2909 if (vp->v_vflag & VV_CACHEDLABEL) 2910 strlcat(buf, "|VV_CACHEDLABEL", sizeof(buf)); 2911 if (vp->v_vflag & VV_TEXT) 2912 strlcat(buf, "|VV_TEXT", sizeof(buf)); 2913 if (vp->v_vflag & VV_COPYONWRITE) 2914 strlcat(buf, "|VV_COPYONWRITE", sizeof(buf)); 2915 if (vp->v_vflag & VV_SYSTEM) 2916 strlcat(buf, "|VV_SYSTEM", sizeof(buf)); 2917 if (vp->v_vflag & VV_PROCDEP) 2918 strlcat(buf, "|VV_PROCDEP", sizeof(buf)); 2919 if (vp->v_vflag & VV_NOKNOTE) 2920 strlcat(buf, "|VV_NOKNOTE", sizeof(buf)); 2921 if (vp->v_vflag & VV_DELETED) 2922 strlcat(buf, "|VV_DELETED", sizeof(buf)); 2923 if (vp->v_vflag & VV_MD) 2924 strlcat(buf, "|VV_MD", sizeof(buf)); 2925 if (vp->v_vflag & VV_FORCEINSMQ) 2926 strlcat(buf, "|VV_FORCEINSMQ", sizeof(buf)); 2927 flags = vp->v_vflag & ~(VV_ROOT | VV_ISTTY | VV_NOSYNC | VV_ETERNALDEV | 2928 VV_CACHEDLABEL | VV_TEXT | VV_COPYONWRITE | VV_SYSTEM | VV_PROCDEP | 2929 VV_NOKNOTE | VV_DELETED | VV_MD | VV_FORCEINSMQ); 2930 if (flags != 0) { 2931 snprintf(buf2, sizeof(buf2), "|VV(0x%lx)", flags); 2932 strlcat(buf, buf2, sizeof(buf)); 2933 } 2934 if (vp->v_iflag & VI_MOUNT) 2935 strlcat(buf, "|VI_MOUNT", sizeof(buf)); 2936 if (vp->v_iflag & VI_AGE) 2937 strlcat(buf, "|VI_AGE", sizeof(buf)); 2938 if (vp->v_iflag & VI_DOOMED) 2939 strlcat(buf, "|VI_DOOMED", sizeof(buf)); 2940 if (vp->v_iflag & VI_FREE) 2941 strlcat(buf, "|VI_FREE", sizeof(buf)); 2942 if (vp->v_iflag & VI_ACTIVE) 2943 strlcat(buf, "|VI_ACTIVE", sizeof(buf)); 2944 if (vp->v_iflag & VI_DOINGINACT) 2945 strlcat(buf, "|VI_DOINGINACT", sizeof(buf)); 2946 if (vp->v_iflag & VI_OWEINACT) 2947 strlcat(buf, "|VI_OWEINACT", sizeof(buf)); 2948 flags = vp->v_iflag & ~(VI_MOUNT | VI_AGE | VI_DOOMED | VI_FREE | 2949 VI_ACTIVE | VI_DOINGINACT | VI_OWEINACT); 2950 if (flags != 0) { 2951 snprintf(buf2, sizeof(buf2), "|VI(0x%lx)", flags); 2952 strlcat(buf, buf2, sizeof(buf)); 2953 } 2954 printf(" flags (%s)\n", buf + 1); 2955 if (mtx_owned(VI_MTX(vp))) 2956 printf(" VI_LOCKed"); 2957 if (vp->v_object != NULL) 2958 printf(" v_object %p ref %d pages %d\n", 2959 vp->v_object, vp->v_object->ref_count, 2960 vp->v_object->resident_page_count); 2961 printf(" "); 2962 lockmgr_printinfo(vp->v_vnlock); 2963 if (vp->v_data != NULL) 2964 VOP_PRINT(vp); 2965 } 2966 2967 #ifdef DDB 2968 /* 2969 * List all of the locked vnodes in the system. 2970 * Called when debugging the kernel. 2971 */ 2972 DB_SHOW_COMMAND(lockedvnods, lockedvnodes) 2973 { 2974 struct mount *mp, *nmp; 2975 struct vnode *vp; 2976 2977 /* 2978 * Note: because this is DDB, we can't obey the locking semantics 2979 * for these structures, which means we could catch an inconsistent 2980 * state and dereference a nasty pointer. Not much to be done 2981 * about that. 2982 */ 2983 db_printf("Locked vnodes\n"); 2984 for (mp = TAILQ_FIRST(&mountlist); mp != NULL; mp = nmp) { 2985 nmp = TAILQ_NEXT(mp, mnt_list); 2986 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) { 2987 if (vp->v_type != VMARKER && 2988 VOP_ISLOCKED(vp)) 2989 vprint("", vp); 2990 } 2991 nmp = TAILQ_NEXT(mp, mnt_list); 2992 } 2993 } 2994 2995 /* 2996 * Show details about the given vnode. 2997 */ 2998 DB_SHOW_COMMAND(vnode, db_show_vnode) 2999 { 3000 struct vnode *vp; 3001 3002 if (!have_addr) 3003 return; 3004 vp = (struct vnode *)addr; 3005 vn_printf(vp, "vnode "); 3006 } 3007 3008 /* 3009 * Show details about the given mount point. 3010 */ 3011 DB_SHOW_COMMAND(mount, db_show_mount) 3012 { 3013 struct mount *mp; 3014 struct vfsopt *opt; 3015 struct statfs *sp; 3016 struct vnode *vp; 3017 char buf[512]; 3018 uint64_t mflags; 3019 u_int flags; 3020 3021 if (!have_addr) { 3022 /* No address given, print short info about all mount points. */ 3023 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 3024 db_printf("%p %s on %s (%s)\n", mp, 3025 mp->mnt_stat.f_mntfromname, 3026 mp->mnt_stat.f_mntonname, 3027 mp->mnt_stat.f_fstypename); 3028 if (db_pager_quit) 3029 break; 3030 } 3031 db_printf("\nMore info: show mount <addr>\n"); 3032 return; 3033 } 3034 3035 mp = (struct mount *)addr; 3036 db_printf("%p %s on %s (%s)\n", mp, mp->mnt_stat.f_mntfromname, 3037 mp->mnt_stat.f_mntonname, mp->mnt_stat.f_fstypename); 3038 3039 buf[0] = '\0'; 3040 mflags = mp->mnt_flag; 3041 #define MNT_FLAG(flag) do { \ 3042 if (mflags & (flag)) { \ 3043 if (buf[0] != '\0') \ 3044 strlcat(buf, ", ", sizeof(buf)); \ 3045 strlcat(buf, (#flag) + 4, sizeof(buf)); \ 3046 mflags &= ~(flag); \ 3047 } \ 3048 } while (0) 3049 MNT_FLAG(MNT_RDONLY); 3050 MNT_FLAG(MNT_SYNCHRONOUS); 3051 MNT_FLAG(MNT_NOEXEC); 3052 MNT_FLAG(MNT_NOSUID); 3053 MNT_FLAG(MNT_NFS4ACLS); 3054 MNT_FLAG(MNT_UNION); 3055 MNT_FLAG(MNT_ASYNC); 3056 MNT_FLAG(MNT_SUIDDIR); 3057 MNT_FLAG(MNT_SOFTDEP); 3058 MNT_FLAG(MNT_NOSYMFOLLOW); 3059 MNT_FLAG(MNT_GJOURNAL); 3060 MNT_FLAG(MNT_MULTILABEL); 3061 MNT_FLAG(MNT_ACLS); 3062 MNT_FLAG(MNT_NOATIME); 3063 MNT_FLAG(MNT_NOCLUSTERR); 3064 MNT_FLAG(MNT_NOCLUSTERW); 3065 MNT_FLAG(MNT_SUJ); 3066 MNT_FLAG(MNT_EXRDONLY); 3067 MNT_FLAG(MNT_EXPORTED); 3068 MNT_FLAG(MNT_DEFEXPORTED); 3069 MNT_FLAG(MNT_EXPORTANON); 3070 MNT_FLAG(MNT_EXKERB); 3071 MNT_FLAG(MNT_EXPUBLIC); 3072 MNT_FLAG(MNT_LOCAL); 3073 MNT_FLAG(MNT_QUOTA); 3074 MNT_FLAG(MNT_ROOTFS); 3075 MNT_FLAG(MNT_USER); 3076 MNT_FLAG(MNT_IGNORE); 3077 MNT_FLAG(MNT_UPDATE); 3078 MNT_FLAG(MNT_DELEXPORT); 3079 MNT_FLAG(MNT_RELOAD); 3080 MNT_FLAG(MNT_FORCE); 3081 MNT_FLAG(MNT_SNAPSHOT); 3082 MNT_FLAG(MNT_BYFSID); 3083 #undef MNT_FLAG 3084 if (mflags != 0) { 3085 if (buf[0] != '\0') 3086 strlcat(buf, ", ", sizeof(buf)); 3087 snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf), 3088 "0x%016jx", mflags); 3089 } 3090 db_printf(" mnt_flag = %s\n", buf); 3091 3092 buf[0] = '\0'; 3093 flags = mp->mnt_kern_flag; 3094 #define MNT_KERN_FLAG(flag) do { \ 3095 if (flags & (flag)) { \ 3096 if (buf[0] != '\0') \ 3097 strlcat(buf, ", ", sizeof(buf)); \ 3098 strlcat(buf, (#flag) + 5, sizeof(buf)); \ 3099 flags &= ~(flag); \ 3100 } \ 3101 } while (0) 3102 MNT_KERN_FLAG(MNTK_UNMOUNTF); 3103 MNT_KERN_FLAG(MNTK_ASYNC); 3104 MNT_KERN_FLAG(MNTK_SOFTDEP); 3105 MNT_KERN_FLAG(MNTK_NOINSMNTQ); 3106 MNT_KERN_FLAG(MNTK_DRAINING); 3107 MNT_KERN_FLAG(MNTK_REFEXPIRE); 3108 MNT_KERN_FLAG(MNTK_EXTENDED_SHARED); 3109 MNT_KERN_FLAG(MNTK_SHARED_WRITES); 3110 MNT_KERN_FLAG(MNTK_NO_IOPF); 3111 MNT_KERN_FLAG(MNTK_VGONE_UPPER); 3112 MNT_KERN_FLAG(MNTK_VGONE_WAITER); 3113 MNT_KERN_FLAG(MNTK_LOOKUP_EXCL_DOTDOT); 3114 MNT_KERN_FLAG(MNTK_MARKER); 3115 MNT_KERN_FLAG(MNTK_NOASYNC); 3116 MNT_KERN_FLAG(MNTK_UNMOUNT); 3117 MNT_KERN_FLAG(MNTK_MWAIT); 3118 MNT_KERN_FLAG(MNTK_SUSPEND); 3119 MNT_KERN_FLAG(MNTK_SUSPEND2); 3120 MNT_KERN_FLAG(MNTK_SUSPENDED); 3121 MNT_KERN_FLAG(MNTK_LOOKUP_SHARED); 3122 MNT_KERN_FLAG(MNTK_NOKNOTE); 3123 #undef MNT_KERN_FLAG 3124 if (flags != 0) { 3125 if (buf[0] != '\0') 3126 strlcat(buf, ", ", sizeof(buf)); 3127 snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf), 3128 "0x%08x", flags); 3129 } 3130 db_printf(" mnt_kern_flag = %s\n", buf); 3131 3132 db_printf(" mnt_opt = "); 3133 opt = TAILQ_FIRST(mp->mnt_opt); 3134 if (opt != NULL) { 3135 db_printf("%s", opt->name); 3136 opt = TAILQ_NEXT(opt, link); 3137 while (opt != NULL) { 3138 db_printf(", %s", opt->name); 3139 opt = TAILQ_NEXT(opt, link); 3140 } 3141 } 3142 db_printf("\n"); 3143 3144 sp = &mp->mnt_stat; 3145 db_printf(" mnt_stat = { version=%u type=%u flags=0x%016jx " 3146 "bsize=%ju iosize=%ju blocks=%ju bfree=%ju bavail=%jd files=%ju " 3147 "ffree=%jd syncwrites=%ju asyncwrites=%ju syncreads=%ju " 3148 "asyncreads=%ju namemax=%u owner=%u fsid=[%d, %d] }\n", 3149 (u_int)sp->f_version, (u_int)sp->f_type, (uintmax_t)sp->f_flags, 3150 (uintmax_t)sp->f_bsize, (uintmax_t)sp->f_iosize, 3151 (uintmax_t)sp->f_blocks, (uintmax_t)sp->f_bfree, 3152 (intmax_t)sp->f_bavail, (uintmax_t)sp->f_files, 3153 (intmax_t)sp->f_ffree, (uintmax_t)sp->f_syncwrites, 3154 (uintmax_t)sp->f_asyncwrites, (uintmax_t)sp->f_syncreads, 3155 (uintmax_t)sp->f_asyncreads, (u_int)sp->f_namemax, 3156 (u_int)sp->f_owner, (int)sp->f_fsid.val[0], (int)sp->f_fsid.val[1]); 3157 3158 db_printf(" mnt_cred = { uid=%u ruid=%u", 3159 (u_int)mp->mnt_cred->cr_uid, (u_int)mp->mnt_cred->cr_ruid); 3160 if (jailed(mp->mnt_cred)) 3161 db_printf(", jail=%d", mp->mnt_cred->cr_prison->pr_id); 3162 db_printf(" }\n"); 3163 db_printf(" mnt_ref = %d\n", mp->mnt_ref); 3164 db_printf(" mnt_gen = %d\n", mp->mnt_gen); 3165 db_printf(" mnt_nvnodelistsize = %d\n", mp->mnt_nvnodelistsize); 3166 db_printf(" mnt_activevnodelistsize = %d\n", 3167 mp->mnt_activevnodelistsize); 3168 db_printf(" mnt_writeopcount = %d\n", mp->mnt_writeopcount); 3169 db_printf(" mnt_maxsymlinklen = %d\n", mp->mnt_maxsymlinklen); 3170 db_printf(" mnt_iosize_max = %d\n", mp->mnt_iosize_max); 3171 db_printf(" mnt_hashseed = %u\n", mp->mnt_hashseed); 3172 db_printf(" mnt_secondary_writes = %d\n", mp->mnt_secondary_writes); 3173 db_printf(" mnt_secondary_accwrites = %d\n", 3174 mp->mnt_secondary_accwrites); 3175 db_printf(" mnt_gjprovider = %s\n", 3176 mp->mnt_gjprovider != NULL ? mp->mnt_gjprovider : "NULL"); 3177 3178 db_printf("\n\nList of active vnodes\n"); 3179 TAILQ_FOREACH(vp, &mp->mnt_activevnodelist, v_actfreelist) { 3180 if (vp->v_type != VMARKER) { 3181 vn_printf(vp, "vnode "); 3182 if (db_pager_quit) 3183 break; 3184 } 3185 } 3186 db_printf("\n\nList of inactive vnodes\n"); 3187 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) { 3188 if (vp->v_type != VMARKER && (vp->v_iflag & VI_ACTIVE) == 0) { 3189 vn_printf(vp, "vnode "); 3190 if (db_pager_quit) 3191 break; 3192 } 3193 } 3194 } 3195 #endif /* DDB */ 3196 3197 /* 3198 * Fill in a struct xvfsconf based on a struct vfsconf. 3199 */ 3200 static int 3201 vfsconf2x(struct sysctl_req *req, struct vfsconf *vfsp) 3202 { 3203 struct xvfsconf xvfsp; 3204 3205 bzero(&xvfsp, sizeof(xvfsp)); 3206 strcpy(xvfsp.vfc_name, vfsp->vfc_name); 3207 xvfsp.vfc_typenum = vfsp->vfc_typenum; 3208 xvfsp.vfc_refcount = vfsp->vfc_refcount; 3209 xvfsp.vfc_flags = vfsp->vfc_flags; 3210 /* 3211 * These are unused in userland, we keep them 3212 * to not break binary compatibility. 3213 */ 3214 xvfsp.vfc_vfsops = NULL; 3215 xvfsp.vfc_next = NULL; 3216 return (SYSCTL_OUT(req, &xvfsp, sizeof(xvfsp))); 3217 } 3218 3219 #ifdef COMPAT_FREEBSD32 3220 struct xvfsconf32 { 3221 uint32_t vfc_vfsops; 3222 char vfc_name[MFSNAMELEN]; 3223 int32_t vfc_typenum; 3224 int32_t vfc_refcount; 3225 int32_t vfc_flags; 3226 uint32_t vfc_next; 3227 }; 3228 3229 static int 3230 vfsconf2x32(struct sysctl_req *req, struct vfsconf *vfsp) 3231 { 3232 struct xvfsconf32 xvfsp; 3233 3234 strcpy(xvfsp.vfc_name, vfsp->vfc_name); 3235 xvfsp.vfc_typenum = vfsp->vfc_typenum; 3236 xvfsp.vfc_refcount = vfsp->vfc_refcount; 3237 xvfsp.vfc_flags = vfsp->vfc_flags; 3238 xvfsp.vfc_vfsops = 0; 3239 xvfsp.vfc_next = 0; 3240 return (SYSCTL_OUT(req, &xvfsp, sizeof(xvfsp))); 3241 } 3242 #endif 3243 3244 /* 3245 * Top level filesystem related information gathering. 3246 */ 3247 static int 3248 sysctl_vfs_conflist(SYSCTL_HANDLER_ARGS) 3249 { 3250 struct vfsconf *vfsp; 3251 int error; 3252 3253 error = 0; 3254 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) { 3255 #ifdef COMPAT_FREEBSD32 3256 if (req->flags & SCTL_MASK32) 3257 error = vfsconf2x32(req, vfsp); 3258 else 3259 #endif 3260 error = vfsconf2x(req, vfsp); 3261 if (error) 3262 break; 3263 } 3264 return (error); 3265 } 3266 3267 SYSCTL_PROC(_vfs, OID_AUTO, conflist, CTLTYPE_OPAQUE | CTLFLAG_RD, 3268 NULL, 0, sysctl_vfs_conflist, 3269 "S,xvfsconf", "List of all configured filesystems"); 3270 3271 #ifndef BURN_BRIDGES 3272 static int sysctl_ovfs_conf(SYSCTL_HANDLER_ARGS); 3273 3274 static int 3275 vfs_sysctl(SYSCTL_HANDLER_ARGS) 3276 { 3277 int *name = (int *)arg1 - 1; /* XXX */ 3278 u_int namelen = arg2 + 1; /* XXX */ 3279 struct vfsconf *vfsp; 3280 3281 log(LOG_WARNING, "userland calling deprecated sysctl, " 3282 "please rebuild world\n"); 3283 3284 #if 1 || defined(COMPAT_PRELITE2) 3285 /* Resolve ambiguity between VFS_VFSCONF and VFS_GENERIC. */ 3286 if (namelen == 1) 3287 return (sysctl_ovfs_conf(oidp, arg1, arg2, req)); 3288 #endif 3289 3290 switch (name[1]) { 3291 case VFS_MAXTYPENUM: 3292 if (namelen != 2) 3293 return (ENOTDIR); 3294 return (SYSCTL_OUT(req, &maxvfsconf, sizeof(int))); 3295 case VFS_CONF: 3296 if (namelen != 3) 3297 return (ENOTDIR); /* overloaded */ 3298 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) 3299 if (vfsp->vfc_typenum == name[2]) 3300 break; 3301 if (vfsp == NULL) 3302 return (EOPNOTSUPP); 3303 #ifdef COMPAT_FREEBSD32 3304 if (req->flags & SCTL_MASK32) 3305 return (vfsconf2x32(req, vfsp)); 3306 else 3307 #endif 3308 return (vfsconf2x(req, vfsp)); 3309 } 3310 return (EOPNOTSUPP); 3311 } 3312 3313 static SYSCTL_NODE(_vfs, VFS_GENERIC, generic, CTLFLAG_RD | CTLFLAG_SKIP, 3314 vfs_sysctl, "Generic filesystem"); 3315 3316 #if 1 || defined(COMPAT_PRELITE2) 3317 3318 static int 3319 sysctl_ovfs_conf(SYSCTL_HANDLER_ARGS) 3320 { 3321 int error; 3322 struct vfsconf *vfsp; 3323 struct ovfsconf ovfs; 3324 3325 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) { 3326 bzero(&ovfs, sizeof(ovfs)); 3327 ovfs.vfc_vfsops = vfsp->vfc_vfsops; /* XXX used as flag */ 3328 strcpy(ovfs.vfc_name, vfsp->vfc_name); 3329 ovfs.vfc_index = vfsp->vfc_typenum; 3330 ovfs.vfc_refcount = vfsp->vfc_refcount; 3331 ovfs.vfc_flags = vfsp->vfc_flags; 3332 error = SYSCTL_OUT(req, &ovfs, sizeof ovfs); 3333 if (error) 3334 return error; 3335 } 3336 return 0; 3337 } 3338 3339 #endif /* 1 || COMPAT_PRELITE2 */ 3340 #endif /* !BURN_BRIDGES */ 3341 3342 #define KINFO_VNODESLOP 10 3343 #ifdef notyet 3344 /* 3345 * Dump vnode list (via sysctl). 3346 */ 3347 /* ARGSUSED */ 3348 static int 3349 sysctl_vnode(SYSCTL_HANDLER_ARGS) 3350 { 3351 struct xvnode *xvn; 3352 struct mount *mp; 3353 struct vnode *vp; 3354 int error, len, n; 3355 3356 /* 3357 * Stale numvnodes access is not fatal here. 3358 */ 3359 req->lock = 0; 3360 len = (numvnodes + KINFO_VNODESLOP) * sizeof *xvn; 3361 if (!req->oldptr) 3362 /* Make an estimate */ 3363 return (SYSCTL_OUT(req, 0, len)); 3364 3365 error = sysctl_wire_old_buffer(req, 0); 3366 if (error != 0) 3367 return (error); 3368 xvn = malloc(len, M_TEMP, M_ZERO | M_WAITOK); 3369 n = 0; 3370 mtx_lock(&mountlist_mtx); 3371 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 3372 if (vfs_busy(mp, MBF_NOWAIT | MBF_MNTLSTLOCK)) 3373 continue; 3374 MNT_ILOCK(mp); 3375 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) { 3376 if (n == len) 3377 break; 3378 vref(vp); 3379 xvn[n].xv_size = sizeof *xvn; 3380 xvn[n].xv_vnode = vp; 3381 xvn[n].xv_id = 0; /* XXX compat */ 3382 #define XV_COPY(field) xvn[n].xv_##field = vp->v_##field 3383 XV_COPY(usecount); 3384 XV_COPY(writecount); 3385 XV_COPY(holdcnt); 3386 XV_COPY(mount); 3387 XV_COPY(numoutput); 3388 XV_COPY(type); 3389 #undef XV_COPY 3390 xvn[n].xv_flag = vp->v_vflag; 3391 3392 switch (vp->v_type) { 3393 case VREG: 3394 case VDIR: 3395 case VLNK: 3396 break; 3397 case VBLK: 3398 case VCHR: 3399 if (vp->v_rdev == NULL) { 3400 vrele(vp); 3401 continue; 3402 } 3403 xvn[n].xv_dev = dev2udev(vp->v_rdev); 3404 break; 3405 case VSOCK: 3406 xvn[n].xv_socket = vp->v_socket; 3407 break; 3408 case VFIFO: 3409 xvn[n].xv_fifo = vp->v_fifoinfo; 3410 break; 3411 case VNON: 3412 case VBAD: 3413 default: 3414 /* shouldn't happen? */ 3415 vrele(vp); 3416 continue; 3417 } 3418 vrele(vp); 3419 ++n; 3420 } 3421 MNT_IUNLOCK(mp); 3422 mtx_lock(&mountlist_mtx); 3423 vfs_unbusy(mp); 3424 if (n == len) 3425 break; 3426 } 3427 mtx_unlock(&mountlist_mtx); 3428 3429 error = SYSCTL_OUT(req, xvn, n * sizeof *xvn); 3430 free(xvn, M_TEMP); 3431 return (error); 3432 } 3433 3434 SYSCTL_PROC(_kern, KERN_VNODE, vnode, CTLTYPE_OPAQUE|CTLFLAG_RD, 3435 0, 0, sysctl_vnode, "S,xvnode", ""); 3436 #endif 3437 3438 /* 3439 * Unmount all filesystems. The list is traversed in reverse order 3440 * of mounting to avoid dependencies. 3441 */ 3442 void 3443 vfs_unmountall(void) 3444 { 3445 struct mount *mp; 3446 struct thread *td; 3447 int error; 3448 3449 CTR1(KTR_VFS, "%s: unmounting all filesystems", __func__); 3450 td = curthread; 3451 3452 /* 3453 * Since this only runs when rebooting, it is not interlocked. 3454 */ 3455 while(!TAILQ_EMPTY(&mountlist)) { 3456 mp = TAILQ_LAST(&mountlist, mntlist); 3457 error = dounmount(mp, MNT_FORCE, td); 3458 if (error) { 3459 TAILQ_REMOVE(&mountlist, mp, mnt_list); 3460 /* 3461 * XXX: Due to the way in which we mount the root 3462 * file system off of devfs, devfs will generate a 3463 * "busy" warning when we try to unmount it before 3464 * the root. Don't print a warning as a result in 3465 * order to avoid false positive errors that may 3466 * cause needless upset. 3467 */ 3468 if (strcmp(mp->mnt_vfc->vfc_name, "devfs") != 0) { 3469 printf("unmount of %s failed (", 3470 mp->mnt_stat.f_mntonname); 3471 if (error == EBUSY) 3472 printf("BUSY)\n"); 3473 else 3474 printf("%d)\n", error); 3475 } 3476 } else { 3477 /* The unmount has removed mp from the mountlist */ 3478 } 3479 } 3480 } 3481 3482 /* 3483 * perform msync on all vnodes under a mount point 3484 * the mount point must be locked. 3485 */ 3486 void 3487 vfs_msync(struct mount *mp, int flags) 3488 { 3489 struct vnode *vp, *mvp; 3490 struct vm_object *obj; 3491 3492 CTR2(KTR_VFS, "%s: mp %p", __func__, mp); 3493 MNT_VNODE_FOREACH_ACTIVE(vp, mp, mvp) { 3494 obj = vp->v_object; 3495 if (obj != NULL && (obj->flags & OBJ_MIGHTBEDIRTY) != 0 && 3496 (flags == MNT_WAIT || VOP_ISLOCKED(vp) == 0)) { 3497 if (!vget(vp, 3498 LK_EXCLUSIVE | LK_RETRY | LK_INTERLOCK, 3499 curthread)) { 3500 if (vp->v_vflag & VV_NOSYNC) { /* unlinked */ 3501 vput(vp); 3502 continue; 3503 } 3504 3505 obj = vp->v_object; 3506 if (obj != NULL) { 3507 VM_OBJECT_WLOCK(obj); 3508 vm_object_page_clean(obj, 0, 0, 3509 flags == MNT_WAIT ? 3510 OBJPC_SYNC : OBJPC_NOSYNC); 3511 VM_OBJECT_WUNLOCK(obj); 3512 } 3513 vput(vp); 3514 } 3515 } else 3516 VI_UNLOCK(vp); 3517 } 3518 } 3519 3520 static void 3521 destroy_vpollinfo(struct vpollinfo *vi) 3522 { 3523 seldrain(&vi->vpi_selinfo); 3524 knlist_destroy(&vi->vpi_selinfo.si_note); 3525 mtx_destroy(&vi->vpi_lock); 3526 uma_zfree(vnodepoll_zone, vi); 3527 } 3528 3529 /* 3530 * Initalize per-vnode helper structure to hold poll-related state. 3531 */ 3532 void 3533 v_addpollinfo(struct vnode *vp) 3534 { 3535 struct vpollinfo *vi; 3536 3537 if (vp->v_pollinfo != NULL) 3538 return; 3539 vi = uma_zalloc(vnodepoll_zone, M_WAITOK); 3540 mtx_init(&vi->vpi_lock, "vnode pollinfo", NULL, MTX_DEF); 3541 knlist_init(&vi->vpi_selinfo.si_note, vp, vfs_knllock, 3542 vfs_knlunlock, vfs_knl_assert_locked, vfs_knl_assert_unlocked); 3543 VI_LOCK(vp); 3544 if (vp->v_pollinfo != NULL) { 3545 VI_UNLOCK(vp); 3546 destroy_vpollinfo(vi); 3547 return; 3548 } 3549 vp->v_pollinfo = vi; 3550 VI_UNLOCK(vp); 3551 } 3552 3553 /* 3554 * Record a process's interest in events which might happen to 3555 * a vnode. Because poll uses the historic select-style interface 3556 * internally, this routine serves as both the ``check for any 3557 * pending events'' and the ``record my interest in future events'' 3558 * functions. (These are done together, while the lock is held, 3559 * to avoid race conditions.) 3560 */ 3561 int 3562 vn_pollrecord(struct vnode *vp, struct thread *td, int events) 3563 { 3564 3565 v_addpollinfo(vp); 3566 mtx_lock(&vp->v_pollinfo->vpi_lock); 3567 if (vp->v_pollinfo->vpi_revents & events) { 3568 /* 3569 * This leaves events we are not interested 3570 * in available for the other process which 3571 * which presumably had requested them 3572 * (otherwise they would never have been 3573 * recorded). 3574 */ 3575 events &= vp->v_pollinfo->vpi_revents; 3576 vp->v_pollinfo->vpi_revents &= ~events; 3577 3578 mtx_unlock(&vp->v_pollinfo->vpi_lock); 3579 return (events); 3580 } 3581 vp->v_pollinfo->vpi_events |= events; 3582 selrecord(td, &vp->v_pollinfo->vpi_selinfo); 3583 mtx_unlock(&vp->v_pollinfo->vpi_lock); 3584 return (0); 3585 } 3586 3587 /* 3588 * Routine to create and manage a filesystem syncer vnode. 3589 */ 3590 #define sync_close ((int (*)(struct vop_close_args *))nullop) 3591 static int sync_fsync(struct vop_fsync_args *); 3592 static int sync_inactive(struct vop_inactive_args *); 3593 static int sync_reclaim(struct vop_reclaim_args *); 3594 3595 static struct vop_vector sync_vnodeops = { 3596 .vop_bypass = VOP_EOPNOTSUPP, 3597 .vop_close = sync_close, /* close */ 3598 .vop_fsync = sync_fsync, /* fsync */ 3599 .vop_inactive = sync_inactive, /* inactive */ 3600 .vop_reclaim = sync_reclaim, /* reclaim */ 3601 .vop_lock1 = vop_stdlock, /* lock */ 3602 .vop_unlock = vop_stdunlock, /* unlock */ 3603 .vop_islocked = vop_stdislocked, /* islocked */ 3604 }; 3605 3606 /* 3607 * Create a new filesystem syncer vnode for the specified mount point. 3608 */ 3609 void 3610 vfs_allocate_syncvnode(struct mount *mp) 3611 { 3612 struct vnode *vp; 3613 struct bufobj *bo; 3614 static long start, incr, next; 3615 int error; 3616 3617 /* Allocate a new vnode */ 3618 error = getnewvnode("syncer", mp, &sync_vnodeops, &vp); 3619 if (error != 0) 3620 panic("vfs_allocate_syncvnode: getnewvnode() failed"); 3621 vp->v_type = VNON; 3622 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 3623 vp->v_vflag |= VV_FORCEINSMQ; 3624 error = insmntque(vp, mp); 3625 if (error != 0) 3626 panic("vfs_allocate_syncvnode: insmntque() failed"); 3627 vp->v_vflag &= ~VV_FORCEINSMQ; 3628 VOP_UNLOCK(vp, 0); 3629 /* 3630 * Place the vnode onto the syncer worklist. We attempt to 3631 * scatter them about on the list so that they will go off 3632 * at evenly distributed times even if all the filesystems 3633 * are mounted at once. 3634 */ 3635 next += incr; 3636 if (next == 0 || next > syncer_maxdelay) { 3637 start /= 2; 3638 incr /= 2; 3639 if (start == 0) { 3640 start = syncer_maxdelay / 2; 3641 incr = syncer_maxdelay; 3642 } 3643 next = start; 3644 } 3645 bo = &vp->v_bufobj; 3646 BO_LOCK(bo); 3647 vn_syncer_add_to_worklist(bo, syncdelay > 0 ? next % syncdelay : 0); 3648 /* XXX - vn_syncer_add_to_worklist() also grabs and drops sync_mtx. */ 3649 mtx_lock(&sync_mtx); 3650 sync_vnode_count++; 3651 if (mp->mnt_syncer == NULL) { 3652 mp->mnt_syncer = vp; 3653 vp = NULL; 3654 } 3655 mtx_unlock(&sync_mtx); 3656 BO_UNLOCK(bo); 3657 if (vp != NULL) { 3658 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 3659 vgone(vp); 3660 vput(vp); 3661 } 3662 } 3663 3664 void 3665 vfs_deallocate_syncvnode(struct mount *mp) 3666 { 3667 struct vnode *vp; 3668 3669 mtx_lock(&sync_mtx); 3670 vp = mp->mnt_syncer; 3671 if (vp != NULL) 3672 mp->mnt_syncer = NULL; 3673 mtx_unlock(&sync_mtx); 3674 if (vp != NULL) 3675 vrele(vp); 3676 } 3677 3678 /* 3679 * Do a lazy sync of the filesystem. 3680 */ 3681 static int 3682 sync_fsync(struct vop_fsync_args *ap) 3683 { 3684 struct vnode *syncvp = ap->a_vp; 3685 struct mount *mp = syncvp->v_mount; 3686 int error, save; 3687 struct bufobj *bo; 3688 3689 /* 3690 * We only need to do something if this is a lazy evaluation. 3691 */ 3692 if (ap->a_waitfor != MNT_LAZY) 3693 return (0); 3694 3695 /* 3696 * Move ourselves to the back of the sync list. 3697 */ 3698 bo = &syncvp->v_bufobj; 3699 BO_LOCK(bo); 3700 vn_syncer_add_to_worklist(bo, syncdelay); 3701 BO_UNLOCK(bo); 3702 3703 /* 3704 * Walk the list of vnodes pushing all that are dirty and 3705 * not already on the sync list. 3706 */ 3707 mtx_lock(&mountlist_mtx); 3708 if (vfs_busy(mp, MBF_NOWAIT | MBF_MNTLSTLOCK) != 0) { 3709 mtx_unlock(&mountlist_mtx); 3710 return (0); 3711 } 3712 if (vn_start_write(NULL, &mp, V_NOWAIT) != 0) { 3713 vfs_unbusy(mp); 3714 return (0); 3715 } 3716 save = curthread_pflags_set(TDP_SYNCIO); 3717 vfs_msync(mp, MNT_NOWAIT); 3718 error = VFS_SYNC(mp, MNT_LAZY); 3719 curthread_pflags_restore(save); 3720 vn_finished_write(mp); 3721 vfs_unbusy(mp); 3722 return (error); 3723 } 3724 3725 /* 3726 * The syncer vnode is no referenced. 3727 */ 3728 static int 3729 sync_inactive(struct vop_inactive_args *ap) 3730 { 3731 3732 vgone(ap->a_vp); 3733 return (0); 3734 } 3735 3736 /* 3737 * The syncer vnode is no longer needed and is being decommissioned. 3738 * 3739 * Modifications to the worklist must be protected by sync_mtx. 3740 */ 3741 static int 3742 sync_reclaim(struct vop_reclaim_args *ap) 3743 { 3744 struct vnode *vp = ap->a_vp; 3745 struct bufobj *bo; 3746 3747 bo = &vp->v_bufobj; 3748 BO_LOCK(bo); 3749 mtx_lock(&sync_mtx); 3750 if (vp->v_mount->mnt_syncer == vp) 3751 vp->v_mount->mnt_syncer = NULL; 3752 if (bo->bo_flag & BO_ONWORKLST) { 3753 LIST_REMOVE(bo, bo_synclist); 3754 syncer_worklist_len--; 3755 sync_vnode_count--; 3756 bo->bo_flag &= ~BO_ONWORKLST; 3757 } 3758 mtx_unlock(&sync_mtx); 3759 BO_UNLOCK(bo); 3760 3761 return (0); 3762 } 3763 3764 /* 3765 * Check if vnode represents a disk device 3766 */ 3767 int 3768 vn_isdisk(struct vnode *vp, int *errp) 3769 { 3770 int error; 3771 3772 error = 0; 3773 dev_lock(); 3774 if (vp->v_type != VCHR) 3775 error = ENOTBLK; 3776 else if (vp->v_rdev == NULL) 3777 error = ENXIO; 3778 else if (vp->v_rdev->si_devsw == NULL) 3779 error = ENXIO; 3780 else if (!(vp->v_rdev->si_devsw->d_flags & D_DISK)) 3781 error = ENOTBLK; 3782 dev_unlock(); 3783 if (errp != NULL) 3784 *errp = error; 3785 return (error == 0); 3786 } 3787 3788 /* 3789 * Common filesystem object access control check routine. Accepts a 3790 * vnode's type, "mode", uid and gid, requested access mode, credentials, 3791 * and optional call-by-reference privused argument allowing vaccess() 3792 * to indicate to the caller whether privilege was used to satisfy the 3793 * request (obsoleted). Returns 0 on success, or an errno on failure. 3794 */ 3795 int 3796 vaccess(enum vtype type, mode_t file_mode, uid_t file_uid, gid_t file_gid, 3797 accmode_t accmode, struct ucred *cred, int *privused) 3798 { 3799 accmode_t dac_granted; 3800 accmode_t priv_granted; 3801 3802 KASSERT((accmode & ~(VEXEC | VWRITE | VREAD | VADMIN | VAPPEND)) == 0, 3803 ("invalid bit in accmode")); 3804 KASSERT((accmode & VAPPEND) == 0 || (accmode & VWRITE), 3805 ("VAPPEND without VWRITE")); 3806 3807 /* 3808 * Look for a normal, non-privileged way to access the file/directory 3809 * as requested. If it exists, go with that. 3810 */ 3811 3812 if (privused != NULL) 3813 *privused = 0; 3814 3815 dac_granted = 0; 3816 3817 /* Check the owner. */ 3818 if (cred->cr_uid == file_uid) { 3819 dac_granted |= VADMIN; 3820 if (file_mode & S_IXUSR) 3821 dac_granted |= VEXEC; 3822 if (file_mode & S_IRUSR) 3823 dac_granted |= VREAD; 3824 if (file_mode & S_IWUSR) 3825 dac_granted |= (VWRITE | VAPPEND); 3826 3827 if ((accmode & dac_granted) == accmode) 3828 return (0); 3829 3830 goto privcheck; 3831 } 3832 3833 /* Otherwise, check the groups (first match) */ 3834 if (groupmember(file_gid, cred)) { 3835 if (file_mode & S_IXGRP) 3836 dac_granted |= VEXEC; 3837 if (file_mode & S_IRGRP) 3838 dac_granted |= VREAD; 3839 if (file_mode & S_IWGRP) 3840 dac_granted |= (VWRITE | VAPPEND); 3841 3842 if ((accmode & dac_granted) == accmode) 3843 return (0); 3844 3845 goto privcheck; 3846 } 3847 3848 /* Otherwise, check everyone else. */ 3849 if (file_mode & S_IXOTH) 3850 dac_granted |= VEXEC; 3851 if (file_mode & S_IROTH) 3852 dac_granted |= VREAD; 3853 if (file_mode & S_IWOTH) 3854 dac_granted |= (VWRITE | VAPPEND); 3855 if ((accmode & dac_granted) == accmode) 3856 return (0); 3857 3858 privcheck: 3859 /* 3860 * Build a privilege mask to determine if the set of privileges 3861 * satisfies the requirements when combined with the granted mask 3862 * from above. For each privilege, if the privilege is required, 3863 * bitwise or the request type onto the priv_granted mask. 3864 */ 3865 priv_granted = 0; 3866 3867 if (type == VDIR) { 3868 /* 3869 * For directories, use PRIV_VFS_LOOKUP to satisfy VEXEC 3870 * requests, instead of PRIV_VFS_EXEC. 3871 */ 3872 if ((accmode & VEXEC) && ((dac_granted & VEXEC) == 0) && 3873 !priv_check_cred(cred, PRIV_VFS_LOOKUP, 0)) 3874 priv_granted |= VEXEC; 3875 } else { 3876 /* 3877 * Ensure that at least one execute bit is on. Otherwise, 3878 * a privileged user will always succeed, and we don't want 3879 * this to happen unless the file really is executable. 3880 */ 3881 if ((accmode & VEXEC) && ((dac_granted & VEXEC) == 0) && 3882 (file_mode & (S_IXUSR | S_IXGRP | S_IXOTH)) != 0 && 3883 !priv_check_cred(cred, PRIV_VFS_EXEC, 0)) 3884 priv_granted |= VEXEC; 3885 } 3886 3887 if ((accmode & VREAD) && ((dac_granted & VREAD) == 0) && 3888 !priv_check_cred(cred, PRIV_VFS_READ, 0)) 3889 priv_granted |= VREAD; 3890 3891 if ((accmode & VWRITE) && ((dac_granted & VWRITE) == 0) && 3892 !priv_check_cred(cred, PRIV_VFS_WRITE, 0)) 3893 priv_granted |= (VWRITE | VAPPEND); 3894 3895 if ((accmode & VADMIN) && ((dac_granted & VADMIN) == 0) && 3896 !priv_check_cred(cred, PRIV_VFS_ADMIN, 0)) 3897 priv_granted |= VADMIN; 3898 3899 if ((accmode & (priv_granted | dac_granted)) == accmode) { 3900 /* XXX audit: privilege used */ 3901 if (privused != NULL) 3902 *privused = 1; 3903 return (0); 3904 } 3905 3906 return ((accmode & VADMIN) ? EPERM : EACCES); 3907 } 3908 3909 /* 3910 * Credential check based on process requesting service, and per-attribute 3911 * permissions. 3912 */ 3913 int 3914 extattr_check_cred(struct vnode *vp, int attrnamespace, struct ucred *cred, 3915 struct thread *td, accmode_t accmode) 3916 { 3917 3918 /* 3919 * Kernel-invoked always succeeds. 3920 */ 3921 if (cred == NOCRED) 3922 return (0); 3923 3924 /* 3925 * Do not allow privileged processes in jail to directly manipulate 3926 * system attributes. 3927 */ 3928 switch (attrnamespace) { 3929 case EXTATTR_NAMESPACE_SYSTEM: 3930 /* Potentially should be: return (EPERM); */ 3931 return (priv_check_cred(cred, PRIV_VFS_EXTATTR_SYSTEM, 0)); 3932 case EXTATTR_NAMESPACE_USER: 3933 return (VOP_ACCESS(vp, accmode, cred, td)); 3934 default: 3935 return (EPERM); 3936 } 3937 } 3938 3939 #ifdef DEBUG_VFS_LOCKS 3940 /* 3941 * This only exists to supress warnings from unlocked specfs accesses. It is 3942 * no longer ok to have an unlocked VFS. 3943 */ 3944 #define IGNORE_LOCK(vp) (panicstr != NULL || (vp) == NULL || \ 3945 (vp)->v_type == VCHR || (vp)->v_type == VBAD) 3946 3947 int vfs_badlock_ddb = 1; /* Drop into debugger on violation. */ 3948 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_ddb, CTLFLAG_RW, &vfs_badlock_ddb, 0, 3949 "Drop into debugger on lock violation"); 3950 3951 int vfs_badlock_mutex = 1; /* Check for interlock across VOPs. */ 3952 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_mutex, CTLFLAG_RW, &vfs_badlock_mutex, 3953 0, "Check for interlock across VOPs"); 3954 3955 int vfs_badlock_print = 1; /* Print lock violations. */ 3956 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_print, CTLFLAG_RW, &vfs_badlock_print, 3957 0, "Print lock violations"); 3958 3959 #ifdef KDB 3960 int vfs_badlock_backtrace = 1; /* Print backtrace at lock violations. */ 3961 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_backtrace, CTLFLAG_RW, 3962 &vfs_badlock_backtrace, 0, "Print backtrace at lock violations"); 3963 #endif 3964 3965 static void 3966 vfs_badlock(const char *msg, const char *str, struct vnode *vp) 3967 { 3968 3969 #ifdef KDB 3970 if (vfs_badlock_backtrace) 3971 kdb_backtrace(); 3972 #endif 3973 if (vfs_badlock_print) 3974 printf("%s: %p %s\n", str, (void *)vp, msg); 3975 if (vfs_badlock_ddb) 3976 kdb_enter(KDB_WHY_VFSLOCK, "lock violation"); 3977 } 3978 3979 void 3980 assert_vi_locked(struct vnode *vp, const char *str) 3981 { 3982 3983 if (vfs_badlock_mutex && !mtx_owned(VI_MTX(vp))) 3984 vfs_badlock("interlock is not locked but should be", str, vp); 3985 } 3986 3987 void 3988 assert_vi_unlocked(struct vnode *vp, const char *str) 3989 { 3990 3991 if (vfs_badlock_mutex && mtx_owned(VI_MTX(vp))) 3992 vfs_badlock("interlock is locked but should not be", str, vp); 3993 } 3994 3995 void 3996 assert_vop_locked(struct vnode *vp, const char *str) 3997 { 3998 int locked; 3999 4000 if (!IGNORE_LOCK(vp)) { 4001 locked = VOP_ISLOCKED(vp); 4002 if (locked == 0 || locked == LK_EXCLOTHER) 4003 vfs_badlock("is not locked but should be", str, vp); 4004 } 4005 } 4006 4007 void 4008 assert_vop_unlocked(struct vnode *vp, const char *str) 4009 { 4010 4011 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) == LK_EXCLUSIVE) 4012 vfs_badlock("is locked but should not be", str, vp); 4013 } 4014 4015 void 4016 assert_vop_elocked(struct vnode *vp, const char *str) 4017 { 4018 4019 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) != LK_EXCLUSIVE) 4020 vfs_badlock("is not exclusive locked but should be", str, vp); 4021 } 4022 4023 #if 0 4024 void 4025 assert_vop_elocked_other(struct vnode *vp, const char *str) 4026 { 4027 4028 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) != LK_EXCLOTHER) 4029 vfs_badlock("is not exclusive locked by another thread", 4030 str, vp); 4031 } 4032 4033 void 4034 assert_vop_slocked(struct vnode *vp, const char *str) 4035 { 4036 4037 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) != LK_SHARED) 4038 vfs_badlock("is not locked shared but should be", str, vp); 4039 } 4040 #endif /* 0 */ 4041 #endif /* DEBUG_VFS_LOCKS */ 4042 4043 void 4044 vop_rename_fail(struct vop_rename_args *ap) 4045 { 4046 4047 if (ap->a_tvp != NULL) 4048 vput(ap->a_tvp); 4049 if (ap->a_tdvp == ap->a_tvp) 4050 vrele(ap->a_tdvp); 4051 else 4052 vput(ap->a_tdvp); 4053 vrele(ap->a_fdvp); 4054 vrele(ap->a_fvp); 4055 } 4056 4057 void 4058 vop_rename_pre(void *ap) 4059 { 4060 struct vop_rename_args *a = ap; 4061 4062 #ifdef DEBUG_VFS_LOCKS 4063 if (a->a_tvp) 4064 ASSERT_VI_UNLOCKED(a->a_tvp, "VOP_RENAME"); 4065 ASSERT_VI_UNLOCKED(a->a_tdvp, "VOP_RENAME"); 4066 ASSERT_VI_UNLOCKED(a->a_fvp, "VOP_RENAME"); 4067 ASSERT_VI_UNLOCKED(a->a_fdvp, "VOP_RENAME"); 4068 4069 /* Check the source (from). */ 4070 if (a->a_tdvp->v_vnlock != a->a_fdvp->v_vnlock && 4071 (a->a_tvp == NULL || a->a_tvp->v_vnlock != a->a_fdvp->v_vnlock)) 4072 ASSERT_VOP_UNLOCKED(a->a_fdvp, "vop_rename: fdvp locked"); 4073 if (a->a_tvp == NULL || a->a_tvp->v_vnlock != a->a_fvp->v_vnlock) 4074 ASSERT_VOP_UNLOCKED(a->a_fvp, "vop_rename: fvp locked"); 4075 4076 /* Check the target. */ 4077 if (a->a_tvp) 4078 ASSERT_VOP_LOCKED(a->a_tvp, "vop_rename: tvp not locked"); 4079 ASSERT_VOP_LOCKED(a->a_tdvp, "vop_rename: tdvp not locked"); 4080 #endif 4081 if (a->a_tdvp != a->a_fdvp) 4082 vhold(a->a_fdvp); 4083 if (a->a_tvp != a->a_fvp) 4084 vhold(a->a_fvp); 4085 vhold(a->a_tdvp); 4086 if (a->a_tvp) 4087 vhold(a->a_tvp); 4088 } 4089 4090 void 4091 vop_strategy_pre(void *ap) 4092 { 4093 #ifdef DEBUG_VFS_LOCKS 4094 struct vop_strategy_args *a; 4095 struct buf *bp; 4096 4097 a = ap; 4098 bp = a->a_bp; 4099 4100 /* 4101 * Cluster ops lock their component buffers but not the IO container. 4102 */ 4103 if ((bp->b_flags & B_CLUSTER) != 0) 4104 return; 4105 4106 if (panicstr == NULL && !BUF_ISLOCKED(bp)) { 4107 if (vfs_badlock_print) 4108 printf( 4109 "VOP_STRATEGY: bp is not locked but should be\n"); 4110 if (vfs_badlock_ddb) 4111 kdb_enter(KDB_WHY_VFSLOCK, "lock violation"); 4112 } 4113 #endif 4114 } 4115 4116 void 4117 vop_lock_pre(void *ap) 4118 { 4119 #ifdef DEBUG_VFS_LOCKS 4120 struct vop_lock1_args *a = ap; 4121 4122 if ((a->a_flags & LK_INTERLOCK) == 0) 4123 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_LOCK"); 4124 else 4125 ASSERT_VI_LOCKED(a->a_vp, "VOP_LOCK"); 4126 #endif 4127 } 4128 4129 void 4130 vop_lock_post(void *ap, int rc) 4131 { 4132 #ifdef DEBUG_VFS_LOCKS 4133 struct vop_lock1_args *a = ap; 4134 4135 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_LOCK"); 4136 if (rc == 0) 4137 ASSERT_VOP_LOCKED(a->a_vp, "VOP_LOCK"); 4138 #endif 4139 } 4140 4141 void 4142 vop_unlock_pre(void *ap) 4143 { 4144 #ifdef DEBUG_VFS_LOCKS 4145 struct vop_unlock_args *a = ap; 4146 4147 if (a->a_flags & LK_INTERLOCK) 4148 ASSERT_VI_LOCKED(a->a_vp, "VOP_UNLOCK"); 4149 ASSERT_VOP_LOCKED(a->a_vp, "VOP_UNLOCK"); 4150 #endif 4151 } 4152 4153 void 4154 vop_unlock_post(void *ap, int rc) 4155 { 4156 #ifdef DEBUG_VFS_LOCKS 4157 struct vop_unlock_args *a = ap; 4158 4159 if (a->a_flags & LK_INTERLOCK) 4160 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_UNLOCK"); 4161 #endif 4162 } 4163 4164 void 4165 vop_create_post(void *ap, int rc) 4166 { 4167 struct vop_create_args *a = ap; 4168 4169 if (!rc) 4170 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 4171 } 4172 4173 void 4174 vop_deleteextattr_post(void *ap, int rc) 4175 { 4176 struct vop_deleteextattr_args *a = ap; 4177 4178 if (!rc) 4179 VFS_KNOTE_LOCKED(a->a_vp, NOTE_ATTRIB); 4180 } 4181 4182 void 4183 vop_link_post(void *ap, int rc) 4184 { 4185 struct vop_link_args *a = ap; 4186 4187 if (!rc) { 4188 VFS_KNOTE_LOCKED(a->a_vp, NOTE_LINK); 4189 VFS_KNOTE_LOCKED(a->a_tdvp, NOTE_WRITE); 4190 } 4191 } 4192 4193 void 4194 vop_mkdir_post(void *ap, int rc) 4195 { 4196 struct vop_mkdir_args *a = ap; 4197 4198 if (!rc) 4199 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE | NOTE_LINK); 4200 } 4201 4202 void 4203 vop_mknod_post(void *ap, int rc) 4204 { 4205 struct vop_mknod_args *a = ap; 4206 4207 if (!rc) 4208 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 4209 } 4210 4211 void 4212 vop_remove_post(void *ap, int rc) 4213 { 4214 struct vop_remove_args *a = ap; 4215 4216 if (!rc) { 4217 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 4218 VFS_KNOTE_LOCKED(a->a_vp, NOTE_DELETE); 4219 } 4220 } 4221 4222 void 4223 vop_rename_post(void *ap, int rc) 4224 { 4225 struct vop_rename_args *a = ap; 4226 4227 if (!rc) { 4228 VFS_KNOTE_UNLOCKED(a->a_fdvp, NOTE_WRITE); 4229 VFS_KNOTE_UNLOCKED(a->a_tdvp, NOTE_WRITE); 4230 VFS_KNOTE_UNLOCKED(a->a_fvp, NOTE_RENAME); 4231 if (a->a_tvp) 4232 VFS_KNOTE_UNLOCKED(a->a_tvp, NOTE_DELETE); 4233 } 4234 if (a->a_tdvp != a->a_fdvp) 4235 vdrop(a->a_fdvp); 4236 if (a->a_tvp != a->a_fvp) 4237 vdrop(a->a_fvp); 4238 vdrop(a->a_tdvp); 4239 if (a->a_tvp) 4240 vdrop(a->a_tvp); 4241 } 4242 4243 void 4244 vop_rmdir_post(void *ap, int rc) 4245 { 4246 struct vop_rmdir_args *a = ap; 4247 4248 if (!rc) { 4249 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE | NOTE_LINK); 4250 VFS_KNOTE_LOCKED(a->a_vp, NOTE_DELETE); 4251 } 4252 } 4253 4254 void 4255 vop_setattr_post(void *ap, int rc) 4256 { 4257 struct vop_setattr_args *a = ap; 4258 4259 if (!rc) 4260 VFS_KNOTE_LOCKED(a->a_vp, NOTE_ATTRIB); 4261 } 4262 4263 void 4264 vop_setextattr_post(void *ap, int rc) 4265 { 4266 struct vop_setextattr_args *a = ap; 4267 4268 if (!rc) 4269 VFS_KNOTE_LOCKED(a->a_vp, NOTE_ATTRIB); 4270 } 4271 4272 void 4273 vop_symlink_post(void *ap, int rc) 4274 { 4275 struct vop_symlink_args *a = ap; 4276 4277 if (!rc) 4278 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 4279 } 4280 4281 static struct knlist fs_knlist; 4282 4283 static void 4284 vfs_event_init(void *arg) 4285 { 4286 knlist_init_mtx(&fs_knlist, NULL); 4287 } 4288 /* XXX - correct order? */ 4289 SYSINIT(vfs_knlist, SI_SUB_VFS, SI_ORDER_ANY, vfs_event_init, NULL); 4290 4291 void 4292 vfs_event_signal(fsid_t *fsid, uint32_t event, intptr_t data __unused) 4293 { 4294 4295 KNOTE_UNLOCKED(&fs_knlist, event); 4296 } 4297 4298 static int filt_fsattach(struct knote *kn); 4299 static void filt_fsdetach(struct knote *kn); 4300 static int filt_fsevent(struct knote *kn, long hint); 4301 4302 struct filterops fs_filtops = { 4303 .f_isfd = 0, 4304 .f_attach = filt_fsattach, 4305 .f_detach = filt_fsdetach, 4306 .f_event = filt_fsevent 4307 }; 4308 4309 static int 4310 filt_fsattach(struct knote *kn) 4311 { 4312 4313 kn->kn_flags |= EV_CLEAR; 4314 knlist_add(&fs_knlist, kn, 0); 4315 return (0); 4316 } 4317 4318 static void 4319 filt_fsdetach(struct knote *kn) 4320 { 4321 4322 knlist_remove(&fs_knlist, kn, 0); 4323 } 4324 4325 static int 4326 filt_fsevent(struct knote *kn, long hint) 4327 { 4328 4329 kn->kn_fflags |= hint; 4330 return (kn->kn_fflags != 0); 4331 } 4332 4333 static int 4334 sysctl_vfs_ctl(SYSCTL_HANDLER_ARGS) 4335 { 4336 struct vfsidctl vc; 4337 int error; 4338 struct mount *mp; 4339 4340 error = SYSCTL_IN(req, &vc, sizeof(vc)); 4341 if (error) 4342 return (error); 4343 if (vc.vc_vers != VFS_CTL_VERS1) 4344 return (EINVAL); 4345 mp = vfs_getvfs(&vc.vc_fsid); 4346 if (mp == NULL) 4347 return (ENOENT); 4348 /* ensure that a specific sysctl goes to the right filesystem. */ 4349 if (strcmp(vc.vc_fstypename, "*") != 0 && 4350 strcmp(vc.vc_fstypename, mp->mnt_vfc->vfc_name) != 0) { 4351 vfs_rel(mp); 4352 return (EINVAL); 4353 } 4354 VCTLTOREQ(&vc, req); 4355 error = VFS_SYSCTL(mp, vc.vc_op, req); 4356 vfs_rel(mp); 4357 return (error); 4358 } 4359 4360 SYSCTL_PROC(_vfs, OID_AUTO, ctl, CTLTYPE_OPAQUE | CTLFLAG_WR, 4361 NULL, 0, sysctl_vfs_ctl, "", 4362 "Sysctl by fsid"); 4363 4364 /* 4365 * Function to initialize a va_filerev field sensibly. 4366 * XXX: Wouldn't a random number make a lot more sense ?? 4367 */ 4368 u_quad_t 4369 init_va_filerev(void) 4370 { 4371 struct bintime bt; 4372 4373 getbinuptime(&bt); 4374 return (((u_quad_t)bt.sec << 32LL) | (bt.frac >> 32LL)); 4375 } 4376 4377 static int filt_vfsread(struct knote *kn, long hint); 4378 static int filt_vfswrite(struct knote *kn, long hint); 4379 static int filt_vfsvnode(struct knote *kn, long hint); 4380 static void filt_vfsdetach(struct knote *kn); 4381 static struct filterops vfsread_filtops = { 4382 .f_isfd = 1, 4383 .f_detach = filt_vfsdetach, 4384 .f_event = filt_vfsread 4385 }; 4386 static struct filterops vfswrite_filtops = { 4387 .f_isfd = 1, 4388 .f_detach = filt_vfsdetach, 4389 .f_event = filt_vfswrite 4390 }; 4391 static struct filterops vfsvnode_filtops = { 4392 .f_isfd = 1, 4393 .f_detach = filt_vfsdetach, 4394 .f_event = filt_vfsvnode 4395 }; 4396 4397 static void 4398 vfs_knllock(void *arg) 4399 { 4400 struct vnode *vp = arg; 4401 4402 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 4403 } 4404 4405 static void 4406 vfs_knlunlock(void *arg) 4407 { 4408 struct vnode *vp = arg; 4409 4410 VOP_UNLOCK(vp, 0); 4411 } 4412 4413 static void 4414 vfs_knl_assert_locked(void *arg) 4415 { 4416 #ifdef DEBUG_VFS_LOCKS 4417 struct vnode *vp = arg; 4418 4419 ASSERT_VOP_LOCKED(vp, "vfs_knl_assert_locked"); 4420 #endif 4421 } 4422 4423 static void 4424 vfs_knl_assert_unlocked(void *arg) 4425 { 4426 #ifdef DEBUG_VFS_LOCKS 4427 struct vnode *vp = arg; 4428 4429 ASSERT_VOP_UNLOCKED(vp, "vfs_knl_assert_unlocked"); 4430 #endif 4431 } 4432 4433 int 4434 vfs_kqfilter(struct vop_kqfilter_args *ap) 4435 { 4436 struct vnode *vp = ap->a_vp; 4437 struct knote *kn = ap->a_kn; 4438 struct knlist *knl; 4439 4440 switch (kn->kn_filter) { 4441 case EVFILT_READ: 4442 kn->kn_fop = &vfsread_filtops; 4443 break; 4444 case EVFILT_WRITE: 4445 kn->kn_fop = &vfswrite_filtops; 4446 break; 4447 case EVFILT_VNODE: 4448 kn->kn_fop = &vfsvnode_filtops; 4449 break; 4450 default: 4451 return (EINVAL); 4452 } 4453 4454 kn->kn_hook = (caddr_t)vp; 4455 4456 v_addpollinfo(vp); 4457 if (vp->v_pollinfo == NULL) 4458 return (ENOMEM); 4459 knl = &vp->v_pollinfo->vpi_selinfo.si_note; 4460 knlist_add(knl, kn, 0); 4461 4462 return (0); 4463 } 4464 4465 /* 4466 * Detach knote from vnode 4467 */ 4468 static void 4469 filt_vfsdetach(struct knote *kn) 4470 { 4471 struct vnode *vp = (struct vnode *)kn->kn_hook; 4472 4473 KASSERT(vp->v_pollinfo != NULL, ("Missing v_pollinfo")); 4474 knlist_remove(&vp->v_pollinfo->vpi_selinfo.si_note, kn, 0); 4475 } 4476 4477 /*ARGSUSED*/ 4478 static int 4479 filt_vfsread(struct knote *kn, long hint) 4480 { 4481 struct vnode *vp = (struct vnode *)kn->kn_hook; 4482 struct vattr va; 4483 int res; 4484 4485 /* 4486 * filesystem is gone, so set the EOF flag and schedule 4487 * the knote for deletion. 4488 */ 4489 if (hint == NOTE_REVOKE) { 4490 VI_LOCK(vp); 4491 kn->kn_flags |= (EV_EOF | EV_ONESHOT); 4492 VI_UNLOCK(vp); 4493 return (1); 4494 } 4495 4496 if (VOP_GETATTR(vp, &va, curthread->td_ucred)) 4497 return (0); 4498 4499 VI_LOCK(vp); 4500 kn->kn_data = va.va_size - kn->kn_fp->f_offset; 4501 res = (kn->kn_data != 0); 4502 VI_UNLOCK(vp); 4503 return (res); 4504 } 4505 4506 /*ARGSUSED*/ 4507 static int 4508 filt_vfswrite(struct knote *kn, long hint) 4509 { 4510 struct vnode *vp = (struct vnode *)kn->kn_hook; 4511 4512 VI_LOCK(vp); 4513 4514 /* 4515 * filesystem is gone, so set the EOF flag and schedule 4516 * the knote for deletion. 4517 */ 4518 if (hint == NOTE_REVOKE) 4519 kn->kn_flags |= (EV_EOF | EV_ONESHOT); 4520 4521 kn->kn_data = 0; 4522 VI_UNLOCK(vp); 4523 return (1); 4524 } 4525 4526 static int 4527 filt_vfsvnode(struct knote *kn, long hint) 4528 { 4529 struct vnode *vp = (struct vnode *)kn->kn_hook; 4530 int res; 4531 4532 VI_LOCK(vp); 4533 if (kn->kn_sfflags & hint) 4534 kn->kn_fflags |= hint; 4535 if (hint == NOTE_REVOKE) { 4536 kn->kn_flags |= EV_EOF; 4537 VI_UNLOCK(vp); 4538 return (1); 4539 } 4540 res = (kn->kn_fflags != 0); 4541 VI_UNLOCK(vp); 4542 return (res); 4543 } 4544 4545 int 4546 vfs_read_dirent(struct vop_readdir_args *ap, struct dirent *dp, off_t off) 4547 { 4548 int error; 4549 4550 if (dp->d_reclen > ap->a_uio->uio_resid) 4551 return (ENAMETOOLONG); 4552 error = uiomove(dp, dp->d_reclen, ap->a_uio); 4553 if (error) { 4554 if (ap->a_ncookies != NULL) { 4555 if (ap->a_cookies != NULL) 4556 free(ap->a_cookies, M_TEMP); 4557 ap->a_cookies = NULL; 4558 *ap->a_ncookies = 0; 4559 } 4560 return (error); 4561 } 4562 if (ap->a_ncookies == NULL) 4563 return (0); 4564 4565 KASSERT(ap->a_cookies, 4566 ("NULL ap->a_cookies value with non-NULL ap->a_ncookies!")); 4567 4568 *ap->a_cookies = realloc(*ap->a_cookies, 4569 (*ap->a_ncookies + 1) * sizeof(u_long), M_TEMP, M_WAITOK | M_ZERO); 4570 (*ap->a_cookies)[*ap->a_ncookies] = off; 4571 return (0); 4572 } 4573 4574 /* 4575 * Mark for update the access time of the file if the filesystem 4576 * supports VOP_MARKATIME. This functionality is used by execve and 4577 * mmap, so we want to avoid the I/O implied by directly setting 4578 * va_atime for the sake of efficiency. 4579 */ 4580 void 4581 vfs_mark_atime(struct vnode *vp, struct ucred *cred) 4582 { 4583 struct mount *mp; 4584 4585 mp = vp->v_mount; 4586 ASSERT_VOP_LOCKED(vp, "vfs_mark_atime"); 4587 if (mp != NULL && (mp->mnt_flag & (MNT_NOATIME | MNT_RDONLY)) == 0) 4588 (void)VOP_MARKATIME(vp); 4589 } 4590 4591 /* 4592 * The purpose of this routine is to remove granularity from accmode_t, 4593 * reducing it into standard unix access bits - VEXEC, VREAD, VWRITE, 4594 * VADMIN and VAPPEND. 4595 * 4596 * If it returns 0, the caller is supposed to continue with the usual 4597 * access checks using 'accmode' as modified by this routine. If it 4598 * returns nonzero value, the caller is supposed to return that value 4599 * as errno. 4600 * 4601 * Note that after this routine runs, accmode may be zero. 4602 */ 4603 int 4604 vfs_unixify_accmode(accmode_t *accmode) 4605 { 4606 /* 4607 * There is no way to specify explicit "deny" rule using 4608 * file mode or POSIX.1e ACLs. 4609 */ 4610 if (*accmode & VEXPLICIT_DENY) { 4611 *accmode = 0; 4612 return (0); 4613 } 4614 4615 /* 4616 * None of these can be translated into usual access bits. 4617 * Also, the common case for NFSv4 ACLs is to not contain 4618 * either of these bits. Caller should check for VWRITE 4619 * on the containing directory instead. 4620 */ 4621 if (*accmode & (VDELETE_CHILD | VDELETE)) 4622 return (EPERM); 4623 4624 if (*accmode & VADMIN_PERMS) { 4625 *accmode &= ~VADMIN_PERMS; 4626 *accmode |= VADMIN; 4627 } 4628 4629 /* 4630 * There is no way to deny VREAD_ATTRIBUTES, VREAD_ACL 4631 * or VSYNCHRONIZE using file mode or POSIX.1e ACL. 4632 */ 4633 *accmode &= ~(VSTAT_PERMS | VSYNCHRONIZE); 4634 4635 return (0); 4636 } 4637 4638 /* 4639 * These are helper functions for filesystems to traverse all 4640 * their vnodes. See MNT_VNODE_FOREACH_ALL() in sys/mount.h. 4641 * 4642 * This interface replaces MNT_VNODE_FOREACH. 4643 */ 4644 4645 MALLOC_DEFINE(M_VNODE_MARKER, "vnodemarker", "vnode marker"); 4646 4647 struct vnode * 4648 __mnt_vnode_next_all(struct vnode **mvp, struct mount *mp) 4649 { 4650 struct vnode *vp; 4651 4652 if (should_yield()) 4653 kern_yield(PRI_USER); 4654 MNT_ILOCK(mp); 4655 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch")); 4656 vp = TAILQ_NEXT(*mvp, v_nmntvnodes); 4657 while (vp != NULL && (vp->v_type == VMARKER || 4658 (vp->v_iflag & VI_DOOMED) != 0)) 4659 vp = TAILQ_NEXT(vp, v_nmntvnodes); 4660 4661 /* Check if we are done */ 4662 if (vp == NULL) { 4663 __mnt_vnode_markerfree_all(mvp, mp); 4664 /* MNT_IUNLOCK(mp); -- done in above function */ 4665 mtx_assert(MNT_MTX(mp), MA_NOTOWNED); 4666 return (NULL); 4667 } 4668 TAILQ_REMOVE(&mp->mnt_nvnodelist, *mvp, v_nmntvnodes); 4669 TAILQ_INSERT_AFTER(&mp->mnt_nvnodelist, vp, *mvp, v_nmntvnodes); 4670 VI_LOCK(vp); 4671 MNT_IUNLOCK(mp); 4672 return (vp); 4673 } 4674 4675 struct vnode * 4676 __mnt_vnode_first_all(struct vnode **mvp, struct mount *mp) 4677 { 4678 struct vnode *vp; 4679 4680 *mvp = malloc(sizeof(struct vnode), M_VNODE_MARKER, M_WAITOK | M_ZERO); 4681 MNT_ILOCK(mp); 4682 MNT_REF(mp); 4683 (*mvp)->v_type = VMARKER; 4684 4685 vp = TAILQ_FIRST(&mp->mnt_nvnodelist); 4686 while (vp != NULL && (vp->v_type == VMARKER || 4687 (vp->v_iflag & VI_DOOMED) != 0)) 4688 vp = TAILQ_NEXT(vp, v_nmntvnodes); 4689 4690 /* Check if we are done */ 4691 if (vp == NULL) { 4692 MNT_REL(mp); 4693 MNT_IUNLOCK(mp); 4694 free(*mvp, M_VNODE_MARKER); 4695 *mvp = NULL; 4696 return (NULL); 4697 } 4698 (*mvp)->v_mount = mp; 4699 TAILQ_INSERT_AFTER(&mp->mnt_nvnodelist, vp, *mvp, v_nmntvnodes); 4700 VI_LOCK(vp); 4701 MNT_IUNLOCK(mp); 4702 return (vp); 4703 } 4704 4705 4706 void 4707 __mnt_vnode_markerfree_all(struct vnode **mvp, struct mount *mp) 4708 { 4709 4710 if (*mvp == NULL) { 4711 MNT_IUNLOCK(mp); 4712 return; 4713 } 4714 4715 mtx_assert(MNT_MTX(mp), MA_OWNED); 4716 4717 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch")); 4718 TAILQ_REMOVE(&mp->mnt_nvnodelist, *mvp, v_nmntvnodes); 4719 MNT_REL(mp); 4720 MNT_IUNLOCK(mp); 4721 free(*mvp, M_VNODE_MARKER); 4722 *mvp = NULL; 4723 } 4724 4725 /* 4726 * These are helper functions for filesystems to traverse their 4727 * active vnodes. See MNT_VNODE_FOREACH_ACTIVE() in sys/mount.h 4728 */ 4729 static void 4730 mnt_vnode_markerfree_active(struct vnode **mvp, struct mount *mp) 4731 { 4732 4733 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch")); 4734 4735 MNT_ILOCK(mp); 4736 MNT_REL(mp); 4737 MNT_IUNLOCK(mp); 4738 free(*mvp, M_VNODE_MARKER); 4739 *mvp = NULL; 4740 } 4741 4742 static struct vnode * 4743 mnt_vnode_next_active(struct vnode **mvp, struct mount *mp) 4744 { 4745 struct vnode *vp, *nvp; 4746 4747 mtx_assert(&vnode_free_list_mtx, MA_OWNED); 4748 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch")); 4749 restart: 4750 vp = TAILQ_NEXT(*mvp, v_actfreelist); 4751 TAILQ_REMOVE(&mp->mnt_activevnodelist, *mvp, v_actfreelist); 4752 while (vp != NULL) { 4753 if (vp->v_type == VMARKER) { 4754 vp = TAILQ_NEXT(vp, v_actfreelist); 4755 continue; 4756 } 4757 if (!VI_TRYLOCK(vp)) { 4758 if (mp_ncpus == 1 || should_yield()) { 4759 TAILQ_INSERT_BEFORE(vp, *mvp, v_actfreelist); 4760 mtx_unlock(&vnode_free_list_mtx); 4761 kern_yield(PRI_USER); 4762 mtx_lock(&vnode_free_list_mtx); 4763 goto restart; 4764 } 4765 continue; 4766 } 4767 KASSERT(vp->v_type != VMARKER, ("locked marker %p", vp)); 4768 KASSERT(vp->v_mount == mp || vp->v_mount == NULL, 4769 ("alien vnode on the active list %p %p", vp, mp)); 4770 if (vp->v_mount == mp && (vp->v_iflag & VI_DOOMED) == 0) 4771 break; 4772 nvp = TAILQ_NEXT(vp, v_actfreelist); 4773 VI_UNLOCK(vp); 4774 vp = nvp; 4775 } 4776 4777 /* Check if we are done */ 4778 if (vp == NULL) { 4779 mtx_unlock(&vnode_free_list_mtx); 4780 mnt_vnode_markerfree_active(mvp, mp); 4781 return (NULL); 4782 } 4783 TAILQ_INSERT_AFTER(&mp->mnt_activevnodelist, vp, *mvp, v_actfreelist); 4784 mtx_unlock(&vnode_free_list_mtx); 4785 ASSERT_VI_LOCKED(vp, "active iter"); 4786 KASSERT((vp->v_iflag & VI_ACTIVE) != 0, ("Non-active vp %p", vp)); 4787 return (vp); 4788 } 4789 4790 struct vnode * 4791 __mnt_vnode_next_active(struct vnode **mvp, struct mount *mp) 4792 { 4793 4794 if (should_yield()) 4795 kern_yield(PRI_USER); 4796 mtx_lock(&vnode_free_list_mtx); 4797 return (mnt_vnode_next_active(mvp, mp)); 4798 } 4799 4800 struct vnode * 4801 __mnt_vnode_first_active(struct vnode **mvp, struct mount *mp) 4802 { 4803 struct vnode *vp; 4804 4805 *mvp = malloc(sizeof(struct vnode), M_VNODE_MARKER, M_WAITOK | M_ZERO); 4806 MNT_ILOCK(mp); 4807 MNT_REF(mp); 4808 MNT_IUNLOCK(mp); 4809 (*mvp)->v_type = VMARKER; 4810 (*mvp)->v_mount = mp; 4811 4812 mtx_lock(&vnode_free_list_mtx); 4813 vp = TAILQ_FIRST(&mp->mnt_activevnodelist); 4814 if (vp == NULL) { 4815 mtx_unlock(&vnode_free_list_mtx); 4816 mnt_vnode_markerfree_active(mvp, mp); 4817 return (NULL); 4818 } 4819 TAILQ_INSERT_BEFORE(vp, *mvp, v_actfreelist); 4820 return (mnt_vnode_next_active(mvp, mp)); 4821 } 4822 4823 void 4824 __mnt_vnode_markerfree_active(struct vnode **mvp, struct mount *mp) 4825 { 4826 4827 if (*mvp == NULL) 4828 return; 4829 4830 mtx_lock(&vnode_free_list_mtx); 4831 TAILQ_REMOVE(&mp->mnt_activevnodelist, *mvp, v_actfreelist); 4832 mtx_unlock(&vnode_free_list_mtx); 4833 mnt_vnode_markerfree_active(mvp, mp); 4834 } 4835