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/sched.h> 71 #include <sys/sleepqueue.h> 72 #include <sys/smp.h> 73 #include <sys/stat.h> 74 #include <sys/sysctl.h> 75 #include <sys/syslog.h> 76 #include <sys/vmmeter.h> 77 #include <sys/vnode.h> 78 #include <sys/watchdog.h> 79 80 #include <machine/stdarg.h> 81 82 #include <security/mac/mac_framework.h> 83 84 #include <vm/vm.h> 85 #include <vm/vm_object.h> 86 #include <vm/vm_extern.h> 87 #include <vm/pmap.h> 88 #include <vm/vm_map.h> 89 #include <vm/vm_page.h> 90 #include <vm/vm_kern.h> 91 #include <vm/uma.h> 92 93 #ifdef DDB 94 #include <ddb/ddb.h> 95 #endif 96 97 static void delmntque(struct vnode *vp); 98 static int flushbuflist(struct bufv *bufv, int flags, struct bufobj *bo, 99 int slpflag, int slptimeo); 100 static void syncer_shutdown(void *arg, int howto); 101 static int vtryrecycle(struct vnode *vp); 102 static void v_incr_usecount(struct vnode *); 103 static void v_decr_usecount(struct vnode *); 104 static void v_decr_useonly(struct vnode *); 105 static void v_upgrade_usecount(struct vnode *); 106 static void vnlru_free(int); 107 static void vgonel(struct vnode *); 108 static void vfs_knllock(void *arg); 109 static void vfs_knlunlock(void *arg); 110 static void vfs_knl_assert_locked(void *arg); 111 static void vfs_knl_assert_unlocked(void *arg); 112 static void destroy_vpollinfo(struct vpollinfo *vi); 113 114 /* 115 * Number of vnodes in existence. Increased whenever getnewvnode() 116 * allocates a new vnode, decreased in vdropl() for VI_DOOMED vnode. 117 */ 118 static unsigned long numvnodes; 119 120 SYSCTL_ULONG(_vfs, OID_AUTO, numvnodes, CTLFLAG_RD, &numvnodes, 0, 121 "Number of vnodes in existence"); 122 123 /* 124 * Conversion tables for conversion from vnode types to inode formats 125 * and back. 126 */ 127 enum vtype iftovt_tab[16] = { 128 VNON, VFIFO, VCHR, VNON, VDIR, VNON, VBLK, VNON, 129 VREG, VNON, VLNK, VNON, VSOCK, VNON, VNON, VBAD, 130 }; 131 int vttoif_tab[10] = { 132 0, S_IFREG, S_IFDIR, S_IFBLK, S_IFCHR, S_IFLNK, 133 S_IFSOCK, S_IFIFO, S_IFMT, S_IFMT 134 }; 135 136 /* 137 * List of vnodes that are ready for recycling. 138 */ 139 static TAILQ_HEAD(freelst, vnode) vnode_free_list; 140 141 /* 142 * Free vnode target. Free vnodes may simply be files which have been stat'd 143 * but not read. This is somewhat common, and a small cache of such files 144 * should be kept to avoid recreation costs. 145 */ 146 static u_long wantfreevnodes; 147 SYSCTL_ULONG(_vfs, OID_AUTO, wantfreevnodes, CTLFLAG_RW, &wantfreevnodes, 0, ""); 148 /* Number of vnodes in the free list. */ 149 static u_long freevnodes; 150 SYSCTL_ULONG(_vfs, OID_AUTO, freevnodes, CTLFLAG_RD, &freevnodes, 0, 151 "Number of vnodes in the free list"); 152 153 static int vlru_allow_cache_src; 154 SYSCTL_INT(_vfs, OID_AUTO, vlru_allow_cache_src, CTLFLAG_RW, 155 &vlru_allow_cache_src, 0, "Allow vlru to reclaim source vnode"); 156 157 /* 158 * Various variables used for debugging the new implementation of 159 * reassignbuf(). 160 * XXX these are probably of (very) limited utility now. 161 */ 162 static int reassignbufcalls; 163 SYSCTL_INT(_vfs, OID_AUTO, reassignbufcalls, CTLFLAG_RW, &reassignbufcalls, 0, 164 "Number of calls to reassignbuf"); 165 166 /* 167 * Cache for the mount type id assigned to NFS. This is used for 168 * special checks in nfs/nfs_nqlease.c and vm/vnode_pager.c. 169 */ 170 int nfs_mount_type = -1; 171 172 /* To keep more than one thread at a time from running vfs_getnewfsid */ 173 static struct mtx mntid_mtx; 174 175 /* 176 * Lock for any access to the following: 177 * vnode_free_list 178 * numvnodes 179 * freevnodes 180 */ 181 static struct mtx vnode_free_list_mtx; 182 183 /* Publicly exported FS */ 184 struct nfs_public nfs_pub; 185 186 /* Zone for allocation of new vnodes - used exclusively by getnewvnode() */ 187 static uma_zone_t vnode_zone; 188 static uma_zone_t vnodepoll_zone; 189 190 /* 191 * The workitem queue. 192 * 193 * It is useful to delay writes of file data and filesystem metadata 194 * for tens of seconds so that quickly created and deleted files need 195 * not waste disk bandwidth being created and removed. To realize this, 196 * we append vnodes to a "workitem" queue. When running with a soft 197 * updates implementation, most pending metadata dependencies should 198 * not wait for more than a few seconds. Thus, mounted on block devices 199 * are delayed only about a half the time that file data is delayed. 200 * Similarly, directory updates are more critical, so are only delayed 201 * about a third the time that file data is delayed. Thus, there are 202 * SYNCER_MAXDELAY queues that are processed round-robin at a rate of 203 * one each second (driven off the filesystem syncer process). The 204 * syncer_delayno variable indicates the next queue that is to be processed. 205 * Items that need to be processed soon are placed in this queue: 206 * 207 * syncer_workitem_pending[syncer_delayno] 208 * 209 * A delay of fifteen seconds is done by placing the request fifteen 210 * entries later in the queue: 211 * 212 * syncer_workitem_pending[(syncer_delayno + 15) & syncer_mask] 213 * 214 */ 215 static int syncer_delayno; 216 static long syncer_mask; 217 LIST_HEAD(synclist, bufobj); 218 static struct synclist *syncer_workitem_pending; 219 /* 220 * The sync_mtx protects: 221 * bo->bo_synclist 222 * sync_vnode_count 223 * syncer_delayno 224 * syncer_state 225 * syncer_workitem_pending 226 * syncer_worklist_len 227 * rushjob 228 */ 229 static struct mtx sync_mtx; 230 static struct cv sync_wakeup; 231 232 #define SYNCER_MAXDELAY 32 233 static int syncer_maxdelay = SYNCER_MAXDELAY; /* maximum delay time */ 234 static int syncdelay = 30; /* max time to delay syncing data */ 235 static int filedelay = 30; /* time to delay syncing files */ 236 SYSCTL_INT(_kern, OID_AUTO, filedelay, CTLFLAG_RW, &filedelay, 0, 237 "Time to delay syncing files (in seconds)"); 238 static int dirdelay = 29; /* time to delay syncing directories */ 239 SYSCTL_INT(_kern, OID_AUTO, dirdelay, CTLFLAG_RW, &dirdelay, 0, 240 "Time to delay syncing directories (in seconds)"); 241 static int metadelay = 28; /* time to delay syncing metadata */ 242 SYSCTL_INT(_kern, OID_AUTO, metadelay, CTLFLAG_RW, &metadelay, 0, 243 "Time to delay syncing metadata (in seconds)"); 244 static int rushjob; /* number of slots to run ASAP */ 245 static int stat_rush_requests; /* number of times I/O speeded up */ 246 SYSCTL_INT(_debug, OID_AUTO, rush_requests, CTLFLAG_RW, &stat_rush_requests, 0, 247 "Number of times I/O speeded up (rush requests)"); 248 249 /* 250 * When shutting down the syncer, run it at four times normal speed. 251 */ 252 #define SYNCER_SHUTDOWN_SPEEDUP 4 253 static int sync_vnode_count; 254 static int syncer_worklist_len; 255 static enum { SYNCER_RUNNING, SYNCER_SHUTTING_DOWN, SYNCER_FINAL_DELAY } 256 syncer_state; 257 258 /* 259 * Number of vnodes we want to exist at any one time. This is mostly used 260 * to size hash tables in vnode-related code. It is normally not used in 261 * getnewvnode(), as wantfreevnodes is normally nonzero.) 262 * 263 * XXX desiredvnodes is historical cruft and should not exist. 264 */ 265 int desiredvnodes; 266 SYSCTL_INT(_kern, KERN_MAXVNODES, maxvnodes, CTLFLAG_RW, 267 &desiredvnodes, 0, "Maximum number of vnodes"); 268 SYSCTL_ULONG(_kern, OID_AUTO, minvnodes, CTLFLAG_RW, 269 &wantfreevnodes, 0, "Minimum number of vnodes (legacy)"); 270 static int vnlru_nowhere; 271 SYSCTL_INT(_debug, OID_AUTO, vnlru_nowhere, CTLFLAG_RW, 272 &vnlru_nowhere, 0, "Number of times the vnlru process ran without success"); 273 274 /* 275 * Macros to control when a vnode is freed and recycled. All require 276 * the vnode interlock. 277 */ 278 #define VCANRECYCLE(vp) (((vp)->v_iflag & VI_FREE) && !(vp)->v_holdcnt) 279 #define VSHOULDFREE(vp) (!((vp)->v_iflag & VI_FREE) && !(vp)->v_holdcnt) 280 #define VSHOULDBUSY(vp) (((vp)->v_iflag & VI_FREE) && (vp)->v_holdcnt) 281 282 /* Shift count for (uintptr_t)vp to initialize vp->v_hash. */ 283 static int vnsz2log; 284 285 /* 286 * Initialize the vnode management data structures. 287 * 288 * Reevaluate the following cap on the number of vnodes after the physical 289 * memory size exceeds 512GB. In the limit, as the physical memory size 290 * grows, the ratio of physical pages to vnodes approaches sixteen to one. 291 */ 292 #ifndef MAXVNODES_MAX 293 #define MAXVNODES_MAX (512 * (1024 * 1024 * 1024 / (int)PAGE_SIZE / 16)) 294 #endif 295 static void 296 vntblinit(void *dummy __unused) 297 { 298 u_int i; 299 int physvnodes, virtvnodes; 300 301 /* 302 * Desiredvnodes is a function of the physical memory size and the 303 * kernel's heap size. Generally speaking, it scales with the 304 * physical memory size. The ratio of desiredvnodes to physical pages 305 * is one to four until desiredvnodes exceeds 98,304. Thereafter, the 306 * marginal ratio of desiredvnodes to physical pages is one to 307 * sixteen. However, desiredvnodes is limited by the kernel's heap 308 * size. The memory required by desiredvnodes vnodes and vm objects 309 * may not exceed one seventh of the kernel's heap size. 310 */ 311 physvnodes = maxproc + cnt.v_page_count / 16 + 3 * min(98304 * 4, 312 cnt.v_page_count) / 16; 313 virtvnodes = vm_kmem_size / (7 * (sizeof(struct vm_object) + 314 sizeof(struct vnode))); 315 desiredvnodes = min(physvnodes, virtvnodes); 316 if (desiredvnodes > MAXVNODES_MAX) { 317 if (bootverbose) 318 printf("Reducing kern.maxvnodes %d -> %d\n", 319 desiredvnodes, MAXVNODES_MAX); 320 desiredvnodes = MAXVNODES_MAX; 321 } 322 wantfreevnodes = desiredvnodes / 4; 323 mtx_init(&mntid_mtx, "mntid", NULL, MTX_DEF); 324 TAILQ_INIT(&vnode_free_list); 325 mtx_init(&vnode_free_list_mtx, "vnode_free_list", NULL, MTX_DEF); 326 vnode_zone = uma_zcreate("VNODE", sizeof (struct vnode), NULL, NULL, 327 NULL, NULL, UMA_ALIGN_PTR, 0); 328 vnodepoll_zone = uma_zcreate("VNODEPOLL", sizeof (struct vpollinfo), 329 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0); 330 /* 331 * Initialize the filesystem syncer. 332 */ 333 syncer_workitem_pending = hashinit(syncer_maxdelay, M_VNODE, 334 &syncer_mask); 335 syncer_maxdelay = syncer_mask + 1; 336 mtx_init(&sync_mtx, "Syncer mtx", NULL, MTX_DEF); 337 cv_init(&sync_wakeup, "syncer"); 338 for (i = 1; i <= sizeof(struct vnode); i <<= 1) 339 vnsz2log++; 340 vnsz2log--; 341 } 342 SYSINIT(vfs, SI_SUB_VFS, SI_ORDER_FIRST, vntblinit, NULL); 343 344 345 /* 346 * Mark a mount point as busy. Used to synchronize access and to delay 347 * unmounting. Eventually, mountlist_mtx is not released on failure. 348 * 349 * vfs_busy() is a custom lock, it can block the caller. 350 * vfs_busy() only sleeps if the unmount is active on the mount point. 351 * For a mountpoint mp, vfs_busy-enforced lock is before lock of any 352 * vnode belonging to mp. 353 * 354 * Lookup uses vfs_busy() to traverse mount points. 355 * root fs var fs 356 * / vnode lock A / vnode lock (/var) D 357 * /var vnode lock B /log vnode lock(/var/log) E 358 * vfs_busy lock C vfs_busy lock F 359 * 360 * Within each file system, the lock order is C->A->B and F->D->E. 361 * 362 * When traversing across mounts, the system follows that lock order: 363 * 364 * C->A->B 365 * | 366 * +->F->D->E 367 * 368 * The lookup() process for namei("/var") illustrates the process: 369 * VOP_LOOKUP() obtains B while A is held 370 * vfs_busy() obtains a shared lock on F while A and B are held 371 * vput() releases lock on B 372 * vput() releases lock on A 373 * VFS_ROOT() obtains lock on D while shared lock on F is held 374 * vfs_unbusy() releases shared lock on F 375 * vn_lock() obtains lock on deadfs vnode vp_crossmp instead of A. 376 * Attempt to lock A (instead of vp_crossmp) while D is held would 377 * violate the global order, causing deadlocks. 378 * 379 * dounmount() locks B while F is drained. 380 */ 381 int 382 vfs_busy(struct mount *mp, int flags) 383 { 384 385 MPASS((flags & ~MBF_MASK) == 0); 386 CTR3(KTR_VFS, "%s: mp %p with flags %d", __func__, mp, flags); 387 388 MNT_ILOCK(mp); 389 MNT_REF(mp); 390 /* 391 * If mount point is currenly being unmounted, sleep until the 392 * mount point fate is decided. If thread doing the unmounting fails, 393 * it will clear MNTK_UNMOUNT flag before waking us up, indicating 394 * that this mount point has survived the unmount attempt and vfs_busy 395 * should retry. Otherwise the unmounter thread will set MNTK_REFEXPIRE 396 * flag in addition to MNTK_UNMOUNT, indicating that mount point is 397 * about to be really destroyed. vfs_busy needs to release its 398 * reference on the mount point in this case and return with ENOENT, 399 * telling the caller that mount mount it tried to busy is no longer 400 * valid. 401 */ 402 while (mp->mnt_kern_flag & MNTK_UNMOUNT) { 403 if (flags & MBF_NOWAIT || mp->mnt_kern_flag & MNTK_REFEXPIRE) { 404 MNT_REL(mp); 405 MNT_IUNLOCK(mp); 406 CTR1(KTR_VFS, "%s: failed busying before sleeping", 407 __func__); 408 return (ENOENT); 409 } 410 if (flags & MBF_MNTLSTLOCK) 411 mtx_unlock(&mountlist_mtx); 412 mp->mnt_kern_flag |= MNTK_MWAIT; 413 msleep(mp, MNT_MTX(mp), PVFS | PDROP, "vfs_busy", 0); 414 if (flags & MBF_MNTLSTLOCK) 415 mtx_lock(&mountlist_mtx); 416 MNT_ILOCK(mp); 417 } 418 if (flags & MBF_MNTLSTLOCK) 419 mtx_unlock(&mountlist_mtx); 420 mp->mnt_lockref++; 421 MNT_IUNLOCK(mp); 422 return (0); 423 } 424 425 /* 426 * Free a busy filesystem. 427 */ 428 void 429 vfs_unbusy(struct mount *mp) 430 { 431 432 CTR2(KTR_VFS, "%s: mp %p", __func__, mp); 433 MNT_ILOCK(mp); 434 MNT_REL(mp); 435 KASSERT(mp->mnt_lockref > 0, ("negative mnt_lockref")); 436 mp->mnt_lockref--; 437 if (mp->mnt_lockref == 0 && (mp->mnt_kern_flag & MNTK_DRAINING) != 0) { 438 MPASS(mp->mnt_kern_flag & MNTK_UNMOUNT); 439 CTR1(KTR_VFS, "%s: waking up waiters", __func__); 440 mp->mnt_kern_flag &= ~MNTK_DRAINING; 441 wakeup(&mp->mnt_lockref); 442 } 443 MNT_IUNLOCK(mp); 444 } 445 446 /* 447 * Lookup a mount point by filesystem identifier. 448 */ 449 struct mount * 450 vfs_getvfs(fsid_t *fsid) 451 { 452 struct mount *mp; 453 454 CTR2(KTR_VFS, "%s: fsid %p", __func__, fsid); 455 mtx_lock(&mountlist_mtx); 456 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 457 if (mp->mnt_stat.f_fsid.val[0] == fsid->val[0] && 458 mp->mnt_stat.f_fsid.val[1] == fsid->val[1]) { 459 vfs_ref(mp); 460 mtx_unlock(&mountlist_mtx); 461 return (mp); 462 } 463 } 464 mtx_unlock(&mountlist_mtx); 465 CTR2(KTR_VFS, "%s: lookup failed for %p id", __func__, fsid); 466 return ((struct mount *) 0); 467 } 468 469 /* 470 * Lookup a mount point by filesystem identifier, busying it before 471 * returning. 472 */ 473 struct mount * 474 vfs_busyfs(fsid_t *fsid) 475 { 476 struct mount *mp; 477 int error; 478 479 CTR2(KTR_VFS, "%s: fsid %p", __func__, fsid); 480 mtx_lock(&mountlist_mtx); 481 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 482 if (mp->mnt_stat.f_fsid.val[0] == fsid->val[0] && 483 mp->mnt_stat.f_fsid.val[1] == fsid->val[1]) { 484 error = vfs_busy(mp, MBF_MNTLSTLOCK); 485 if (error) { 486 mtx_unlock(&mountlist_mtx); 487 return (NULL); 488 } 489 return (mp); 490 } 491 } 492 CTR2(KTR_VFS, "%s: lookup failed for %p id", __func__, fsid); 493 mtx_unlock(&mountlist_mtx); 494 return ((struct mount *) 0); 495 } 496 497 /* 498 * Check if a user can access privileged mount options. 499 */ 500 int 501 vfs_suser(struct mount *mp, struct thread *td) 502 { 503 int error; 504 505 /* 506 * If the thread is jailed, but this is not a jail-friendly file 507 * system, deny immediately. 508 */ 509 if (!(mp->mnt_vfc->vfc_flags & VFCF_JAIL) && jailed(td->td_ucred)) 510 return (EPERM); 511 512 /* 513 * If the file system was mounted outside the jail of the calling 514 * thread, deny immediately. 515 */ 516 if (prison_check(td->td_ucred, mp->mnt_cred) != 0) 517 return (EPERM); 518 519 /* 520 * If file system supports delegated administration, we don't check 521 * for the PRIV_VFS_MOUNT_OWNER privilege - it will be better verified 522 * by the file system itself. 523 * If this is not the user that did original mount, we check for 524 * the PRIV_VFS_MOUNT_OWNER privilege. 525 */ 526 if (!(mp->mnt_vfc->vfc_flags & VFCF_DELEGADMIN) && 527 mp->mnt_cred->cr_uid != td->td_ucred->cr_uid) { 528 if ((error = priv_check(td, PRIV_VFS_MOUNT_OWNER)) != 0) 529 return (error); 530 } 531 return (0); 532 } 533 534 /* 535 * Get a new unique fsid. Try to make its val[0] unique, since this value 536 * will be used to create fake device numbers for stat(). Also try (but 537 * not so hard) make its val[0] unique mod 2^16, since some emulators only 538 * support 16-bit device numbers. We end up with unique val[0]'s for the 539 * first 2^16 calls and unique val[0]'s mod 2^16 for the first 2^8 calls. 540 * 541 * Keep in mind that several mounts may be running in parallel. Starting 542 * the search one past where the previous search terminated is both a 543 * micro-optimization and a defense against returning the same fsid to 544 * different mounts. 545 */ 546 void 547 vfs_getnewfsid(struct mount *mp) 548 { 549 static uint16_t mntid_base; 550 struct mount *nmp; 551 fsid_t tfsid; 552 int mtype; 553 554 CTR2(KTR_VFS, "%s: mp %p", __func__, mp); 555 mtx_lock(&mntid_mtx); 556 mtype = mp->mnt_vfc->vfc_typenum; 557 tfsid.val[1] = mtype; 558 mtype = (mtype & 0xFF) << 24; 559 for (;;) { 560 tfsid.val[0] = makedev(255, 561 mtype | ((mntid_base & 0xFF00) << 8) | (mntid_base & 0xFF)); 562 mntid_base++; 563 if ((nmp = vfs_getvfs(&tfsid)) == NULL) 564 break; 565 vfs_rel(nmp); 566 } 567 mp->mnt_stat.f_fsid.val[0] = tfsid.val[0]; 568 mp->mnt_stat.f_fsid.val[1] = tfsid.val[1]; 569 mtx_unlock(&mntid_mtx); 570 } 571 572 /* 573 * Knob to control the precision of file timestamps: 574 * 575 * 0 = seconds only; nanoseconds zeroed. 576 * 1 = seconds and nanoseconds, accurate within 1/HZ. 577 * 2 = seconds and nanoseconds, truncated to microseconds. 578 * >=3 = seconds and nanoseconds, maximum precision. 579 */ 580 enum { TSP_SEC, TSP_HZ, TSP_USEC, TSP_NSEC }; 581 582 static int timestamp_precision = TSP_SEC; 583 SYSCTL_INT(_vfs, OID_AUTO, timestamp_precision, CTLFLAG_RW, 584 ×tamp_precision, 0, "File timestamp precision (0: seconds, " 585 "1: sec + ns accurate to 1/HZ, 2: sec + ns truncated to ms, " 586 "3+: sec + ns (max. precision))"); 587 588 /* 589 * Get a current timestamp. 590 */ 591 void 592 vfs_timestamp(struct timespec *tsp) 593 { 594 struct timeval tv; 595 596 switch (timestamp_precision) { 597 case TSP_SEC: 598 tsp->tv_sec = time_second; 599 tsp->tv_nsec = 0; 600 break; 601 case TSP_HZ: 602 getnanotime(tsp); 603 break; 604 case TSP_USEC: 605 microtime(&tv); 606 TIMEVAL_TO_TIMESPEC(&tv, tsp); 607 break; 608 case TSP_NSEC: 609 default: 610 nanotime(tsp); 611 break; 612 } 613 } 614 615 /* 616 * Set vnode attributes to VNOVAL 617 */ 618 void 619 vattr_null(struct vattr *vap) 620 { 621 622 vap->va_type = VNON; 623 vap->va_size = VNOVAL; 624 vap->va_bytes = VNOVAL; 625 vap->va_mode = VNOVAL; 626 vap->va_nlink = VNOVAL; 627 vap->va_uid = VNOVAL; 628 vap->va_gid = VNOVAL; 629 vap->va_fsid = VNOVAL; 630 vap->va_fileid = VNOVAL; 631 vap->va_blocksize = VNOVAL; 632 vap->va_rdev = VNOVAL; 633 vap->va_atime.tv_sec = VNOVAL; 634 vap->va_atime.tv_nsec = VNOVAL; 635 vap->va_mtime.tv_sec = VNOVAL; 636 vap->va_mtime.tv_nsec = VNOVAL; 637 vap->va_ctime.tv_sec = VNOVAL; 638 vap->va_ctime.tv_nsec = VNOVAL; 639 vap->va_birthtime.tv_sec = VNOVAL; 640 vap->va_birthtime.tv_nsec = VNOVAL; 641 vap->va_flags = VNOVAL; 642 vap->va_gen = VNOVAL; 643 vap->va_vaflags = 0; 644 } 645 646 /* 647 * This routine is called when we have too many vnodes. It attempts 648 * to free <count> vnodes and will potentially free vnodes that still 649 * have VM backing store (VM backing store is typically the cause 650 * of a vnode blowout so we want to do this). Therefore, this operation 651 * is not considered cheap. 652 * 653 * A number of conditions may prevent a vnode from being reclaimed. 654 * the buffer cache may have references on the vnode, a directory 655 * vnode may still have references due to the namei cache representing 656 * underlying files, or the vnode may be in active use. It is not 657 * desireable to reuse such vnodes. These conditions may cause the 658 * number of vnodes to reach some minimum value regardless of what 659 * you set kern.maxvnodes to. Do not set kern.maxvnodes too low. 660 */ 661 static int 662 vlrureclaim(struct mount *mp) 663 { 664 struct vnode *vp; 665 int done; 666 int trigger; 667 int usevnodes; 668 int count; 669 670 /* 671 * Calculate the trigger point, don't allow user 672 * screwups to blow us up. This prevents us from 673 * recycling vnodes with lots of resident pages. We 674 * aren't trying to free memory, we are trying to 675 * free vnodes. 676 */ 677 usevnodes = desiredvnodes; 678 if (usevnodes <= 0) 679 usevnodes = 1; 680 trigger = cnt.v_page_count * 2 / usevnodes; 681 done = 0; 682 vn_start_write(NULL, &mp, V_WAIT); 683 MNT_ILOCK(mp); 684 count = mp->mnt_nvnodelistsize / 10 + 1; 685 while (count != 0) { 686 vp = TAILQ_FIRST(&mp->mnt_nvnodelist); 687 while (vp != NULL && vp->v_type == VMARKER) 688 vp = TAILQ_NEXT(vp, v_nmntvnodes); 689 if (vp == NULL) 690 break; 691 TAILQ_REMOVE(&mp->mnt_nvnodelist, vp, v_nmntvnodes); 692 TAILQ_INSERT_TAIL(&mp->mnt_nvnodelist, vp, v_nmntvnodes); 693 --count; 694 if (!VI_TRYLOCK(vp)) 695 goto next_iter; 696 /* 697 * If it's been deconstructed already, it's still 698 * referenced, or it exceeds the trigger, skip it. 699 */ 700 if (vp->v_usecount || 701 (!vlru_allow_cache_src && 702 !LIST_EMPTY(&(vp)->v_cache_src)) || 703 (vp->v_iflag & VI_DOOMED) != 0 || (vp->v_object != NULL && 704 vp->v_object->resident_page_count > trigger)) { 705 VI_UNLOCK(vp); 706 goto next_iter; 707 } 708 MNT_IUNLOCK(mp); 709 vholdl(vp); 710 if (VOP_LOCK(vp, LK_INTERLOCK|LK_EXCLUSIVE|LK_NOWAIT)) { 711 vdrop(vp); 712 goto next_iter_mntunlocked; 713 } 714 VI_LOCK(vp); 715 /* 716 * v_usecount may have been bumped after VOP_LOCK() dropped 717 * the vnode interlock and before it was locked again. 718 * 719 * It is not necessary to recheck VI_DOOMED because it can 720 * only be set by another thread that holds both the vnode 721 * lock and vnode interlock. If another thread has the 722 * vnode lock before we get to VOP_LOCK() and obtains the 723 * vnode interlock after VOP_LOCK() drops the vnode 724 * interlock, the other thread will be unable to drop the 725 * vnode lock before our VOP_LOCK() call fails. 726 */ 727 if (vp->v_usecount || 728 (!vlru_allow_cache_src && 729 !LIST_EMPTY(&(vp)->v_cache_src)) || 730 (vp->v_object != NULL && 731 vp->v_object->resident_page_count > trigger)) { 732 VOP_UNLOCK(vp, LK_INTERLOCK); 733 goto next_iter_mntunlocked; 734 } 735 KASSERT((vp->v_iflag & VI_DOOMED) == 0, 736 ("VI_DOOMED unexpectedly detected in vlrureclaim()")); 737 vgonel(vp); 738 VOP_UNLOCK(vp, 0); 739 vdropl(vp); 740 done++; 741 next_iter_mntunlocked: 742 if (!should_yield()) 743 goto relock_mnt; 744 goto yield; 745 next_iter: 746 if (!should_yield()) 747 continue; 748 MNT_IUNLOCK(mp); 749 yield: 750 kern_yield(PRI_USER); 751 relock_mnt: 752 MNT_ILOCK(mp); 753 } 754 MNT_IUNLOCK(mp); 755 vn_finished_write(mp); 756 return done; 757 } 758 759 /* 760 * Attempt to keep the free list at wantfreevnodes length. 761 */ 762 static void 763 vnlru_free(int count) 764 { 765 struct vnode *vp; 766 767 mtx_assert(&vnode_free_list_mtx, MA_OWNED); 768 for (; count > 0; count--) { 769 vp = TAILQ_FIRST(&vnode_free_list); 770 /* 771 * The list can be modified while the free_list_mtx 772 * has been dropped and vp could be NULL here. 773 */ 774 if (!vp) 775 break; 776 VNASSERT(vp->v_op != NULL, vp, 777 ("vnlru_free: vnode already reclaimed.")); 778 KASSERT((vp->v_iflag & VI_FREE) != 0, 779 ("Removing vnode not on freelist")); 780 KASSERT((vp->v_iflag & VI_ACTIVE) == 0, 781 ("Mangling active vnode")); 782 TAILQ_REMOVE(&vnode_free_list, vp, v_actfreelist); 783 /* 784 * Don't recycle if we can't get the interlock. 785 */ 786 if (!VI_TRYLOCK(vp)) { 787 TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_actfreelist); 788 continue; 789 } 790 VNASSERT(VCANRECYCLE(vp), vp, 791 ("vp inconsistent on freelist")); 792 freevnodes--; 793 vp->v_iflag &= ~VI_FREE; 794 vholdl(vp); 795 mtx_unlock(&vnode_free_list_mtx); 796 VI_UNLOCK(vp); 797 vtryrecycle(vp); 798 /* 799 * If the recycled succeeded this vdrop will actually free 800 * the vnode. If not it will simply place it back on 801 * the free list. 802 */ 803 vdrop(vp); 804 mtx_lock(&vnode_free_list_mtx); 805 } 806 } 807 /* 808 * Attempt to recycle vnodes in a context that is always safe to block. 809 * Calling vlrurecycle() from the bowels of filesystem code has some 810 * interesting deadlock problems. 811 */ 812 static struct proc *vnlruproc; 813 static int vnlruproc_sig; 814 815 static void 816 vnlru_proc(void) 817 { 818 struct mount *mp, *nmp; 819 int done; 820 struct proc *p = vnlruproc; 821 822 EVENTHANDLER_REGISTER(shutdown_pre_sync, kproc_shutdown, p, 823 SHUTDOWN_PRI_FIRST); 824 825 for (;;) { 826 kproc_suspend_check(p); 827 mtx_lock(&vnode_free_list_mtx); 828 if (freevnodes > wantfreevnodes) 829 vnlru_free(freevnodes - wantfreevnodes); 830 if (numvnodes <= desiredvnodes * 9 / 10) { 831 vnlruproc_sig = 0; 832 wakeup(&vnlruproc_sig); 833 msleep(vnlruproc, &vnode_free_list_mtx, 834 PVFS|PDROP, "vlruwt", hz); 835 continue; 836 } 837 mtx_unlock(&vnode_free_list_mtx); 838 done = 0; 839 mtx_lock(&mountlist_mtx); 840 for (mp = TAILQ_FIRST(&mountlist); mp != NULL; mp = nmp) { 841 if (vfs_busy(mp, MBF_NOWAIT | MBF_MNTLSTLOCK)) { 842 nmp = TAILQ_NEXT(mp, mnt_list); 843 continue; 844 } 845 done += vlrureclaim(mp); 846 mtx_lock(&mountlist_mtx); 847 nmp = TAILQ_NEXT(mp, mnt_list); 848 vfs_unbusy(mp); 849 } 850 mtx_unlock(&mountlist_mtx); 851 if (done == 0) { 852 #if 0 853 /* These messages are temporary debugging aids */ 854 if (vnlru_nowhere < 5) 855 printf("vnlru process getting nowhere..\n"); 856 else if (vnlru_nowhere == 5) 857 printf("vnlru process messages stopped.\n"); 858 #endif 859 vnlru_nowhere++; 860 tsleep(vnlruproc, PPAUSE, "vlrup", hz * 3); 861 } else 862 kern_yield(PRI_USER); 863 } 864 } 865 866 static struct kproc_desc vnlru_kp = { 867 "vnlru", 868 vnlru_proc, 869 &vnlruproc 870 }; 871 SYSINIT(vnlru, SI_SUB_KTHREAD_UPDATE, SI_ORDER_FIRST, kproc_start, 872 &vnlru_kp); 873 874 /* 875 * Routines having to do with the management of the vnode table. 876 */ 877 878 /* 879 * Try to recycle a freed vnode. We abort if anyone picks up a reference 880 * before we actually vgone(). This function must be called with the vnode 881 * held to prevent the vnode from being returned to the free list midway 882 * through vgone(). 883 */ 884 static int 885 vtryrecycle(struct vnode *vp) 886 { 887 struct mount *vnmp; 888 889 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 890 VNASSERT(vp->v_holdcnt, vp, 891 ("vtryrecycle: Recycling vp %p without a reference.", vp)); 892 /* 893 * This vnode may found and locked via some other list, if so we 894 * can't recycle it yet. 895 */ 896 if (VOP_LOCK(vp, LK_EXCLUSIVE | LK_NOWAIT) != 0) { 897 CTR2(KTR_VFS, 898 "%s: impossible to recycle, vp %p lock is already held", 899 __func__, vp); 900 return (EWOULDBLOCK); 901 } 902 /* 903 * Don't recycle if its filesystem is being suspended. 904 */ 905 if (vn_start_write(vp, &vnmp, V_NOWAIT) != 0) { 906 VOP_UNLOCK(vp, 0); 907 CTR2(KTR_VFS, 908 "%s: impossible to recycle, cannot start the write for %p", 909 __func__, vp); 910 return (EBUSY); 911 } 912 /* 913 * If we got this far, we need to acquire the interlock and see if 914 * anyone picked up this vnode from another list. If not, we will 915 * mark it with DOOMED via vgonel() so that anyone who does find it 916 * will skip over it. 917 */ 918 VI_LOCK(vp); 919 if (vp->v_usecount) { 920 VOP_UNLOCK(vp, LK_INTERLOCK); 921 vn_finished_write(vnmp); 922 CTR2(KTR_VFS, 923 "%s: impossible to recycle, %p is already referenced", 924 __func__, vp); 925 return (EBUSY); 926 } 927 if ((vp->v_iflag & VI_DOOMED) == 0) 928 vgonel(vp); 929 VOP_UNLOCK(vp, LK_INTERLOCK); 930 vn_finished_write(vnmp); 931 return (0); 932 } 933 934 /* 935 * Wait for available vnodes. 936 */ 937 static int 938 getnewvnode_wait(int suspended) 939 { 940 941 mtx_assert(&vnode_free_list_mtx, MA_OWNED); 942 if (numvnodes > desiredvnodes) { 943 if (suspended) { 944 /* 945 * File system is beeing suspended, we cannot risk a 946 * deadlock here, so allocate new vnode anyway. 947 */ 948 if (freevnodes > wantfreevnodes) 949 vnlru_free(freevnodes - wantfreevnodes); 950 return (0); 951 } 952 if (vnlruproc_sig == 0) { 953 vnlruproc_sig = 1; /* avoid unnecessary wakeups */ 954 wakeup(vnlruproc); 955 } 956 msleep(&vnlruproc_sig, &vnode_free_list_mtx, PVFS, 957 "vlruwk", hz); 958 } 959 return (numvnodes > desiredvnodes ? ENFILE : 0); 960 } 961 962 void 963 getnewvnode_reserve(u_int count) 964 { 965 struct thread *td; 966 967 td = curthread; 968 mtx_lock(&vnode_free_list_mtx); 969 while (count > 0) { 970 if (getnewvnode_wait(0) == 0) { 971 count--; 972 td->td_vp_reserv++; 973 numvnodes++; 974 } 975 } 976 mtx_unlock(&vnode_free_list_mtx); 977 } 978 979 void 980 getnewvnode_drop_reserve(void) 981 { 982 struct thread *td; 983 984 td = curthread; 985 mtx_lock(&vnode_free_list_mtx); 986 KASSERT(numvnodes >= td->td_vp_reserv, ("reserve too large")); 987 numvnodes -= td->td_vp_reserv; 988 mtx_unlock(&vnode_free_list_mtx); 989 td->td_vp_reserv = 0; 990 } 991 992 /* 993 * Return the next vnode from the free list. 994 */ 995 int 996 getnewvnode(const char *tag, struct mount *mp, struct vop_vector *vops, 997 struct vnode **vpp) 998 { 999 struct vnode *vp; 1000 struct bufobj *bo; 1001 struct thread *td; 1002 int error; 1003 1004 CTR3(KTR_VFS, "%s: mp %p with tag %s", __func__, mp, tag); 1005 vp = NULL; 1006 td = curthread; 1007 if (td->td_vp_reserv > 0) { 1008 td->td_vp_reserv -= 1; 1009 goto alloc; 1010 } 1011 mtx_lock(&vnode_free_list_mtx); 1012 /* 1013 * Lend our context to reclaim vnodes if they've exceeded the max. 1014 */ 1015 if (freevnodes > wantfreevnodes) 1016 vnlru_free(1); 1017 error = getnewvnode_wait(mp != NULL && (mp->mnt_kern_flag & 1018 MNTK_SUSPEND)); 1019 #if 0 /* XXX Not all VFS_VGET/ffs_vget callers check returns. */ 1020 if (error != 0) { 1021 mtx_unlock(&vnode_free_list_mtx); 1022 return (error); 1023 } 1024 #endif 1025 numvnodes++; 1026 mtx_unlock(&vnode_free_list_mtx); 1027 alloc: 1028 vp = (struct vnode *) uma_zalloc(vnode_zone, M_WAITOK|M_ZERO); 1029 /* 1030 * Setup locks. 1031 */ 1032 vp->v_vnlock = &vp->v_lock; 1033 mtx_init(&vp->v_interlock, "vnode interlock", NULL, MTX_DEF); 1034 /* 1035 * By default, don't allow shared locks unless filesystems 1036 * opt-in. 1037 */ 1038 lockinit(vp->v_vnlock, PVFS, tag, VLKTIMEOUT, LK_NOSHARE); 1039 /* 1040 * Initialize bufobj. 1041 */ 1042 bo = &vp->v_bufobj; 1043 bo->__bo_vnode = vp; 1044 mtx_init(BO_MTX(bo), "bufobj interlock", NULL, MTX_DEF); 1045 bo->bo_ops = &buf_ops_bio; 1046 bo->bo_private = vp; 1047 TAILQ_INIT(&bo->bo_clean.bv_hd); 1048 TAILQ_INIT(&bo->bo_dirty.bv_hd); 1049 /* 1050 * Initialize namecache. 1051 */ 1052 LIST_INIT(&vp->v_cache_src); 1053 TAILQ_INIT(&vp->v_cache_dst); 1054 /* 1055 * Finalize various vnode identity bits. 1056 */ 1057 vp->v_type = VNON; 1058 vp->v_tag = tag; 1059 vp->v_op = vops; 1060 v_incr_usecount(vp); 1061 vp->v_data = NULL; 1062 #ifdef MAC 1063 mac_vnode_init(vp); 1064 if (mp != NULL && (mp->mnt_flag & MNT_MULTILABEL) == 0) 1065 mac_vnode_associate_singlelabel(mp, vp); 1066 else if (mp == NULL && vops != &dead_vnodeops) 1067 printf("NULL mp in getnewvnode()\n"); 1068 #endif 1069 if (mp != NULL) { 1070 bo->bo_bsize = mp->mnt_stat.f_iosize; 1071 if ((mp->mnt_kern_flag & MNTK_NOKNOTE) != 0) 1072 vp->v_vflag |= VV_NOKNOTE; 1073 } 1074 rangelock_init(&vp->v_rl); 1075 1076 /* 1077 * For the filesystems which do not use vfs_hash_insert(), 1078 * still initialize v_hash to have vfs_hash_index() useful. 1079 * E.g., nullfs uses vfs_hash_index() on the lower vnode for 1080 * its own hashing. 1081 */ 1082 vp->v_hash = (uintptr_t)vp >> vnsz2log; 1083 1084 *vpp = vp; 1085 return (0); 1086 } 1087 1088 /* 1089 * Delete from old mount point vnode list, if on one. 1090 */ 1091 static void 1092 delmntque(struct vnode *vp) 1093 { 1094 struct mount *mp; 1095 int active; 1096 1097 mp = vp->v_mount; 1098 if (mp == NULL) 1099 return; 1100 MNT_ILOCK(mp); 1101 VI_LOCK(vp); 1102 KASSERT(mp->mnt_activevnodelistsize <= mp->mnt_nvnodelistsize, 1103 ("Active vnode list size %d > Vnode list size %d", 1104 mp->mnt_activevnodelistsize, mp->mnt_nvnodelistsize)); 1105 active = vp->v_iflag & VI_ACTIVE; 1106 vp->v_iflag &= ~VI_ACTIVE; 1107 if (active) { 1108 mtx_lock(&vnode_free_list_mtx); 1109 TAILQ_REMOVE(&mp->mnt_activevnodelist, vp, v_actfreelist); 1110 mp->mnt_activevnodelistsize--; 1111 mtx_unlock(&vnode_free_list_mtx); 1112 } 1113 vp->v_mount = NULL; 1114 VI_UNLOCK(vp); 1115 VNASSERT(mp->mnt_nvnodelistsize > 0, vp, 1116 ("bad mount point vnode list size")); 1117 TAILQ_REMOVE(&mp->mnt_nvnodelist, vp, v_nmntvnodes); 1118 mp->mnt_nvnodelistsize--; 1119 MNT_REL(mp); 1120 MNT_IUNLOCK(mp); 1121 } 1122 1123 static void 1124 insmntque_stddtr(struct vnode *vp, void *dtr_arg) 1125 { 1126 1127 vp->v_data = NULL; 1128 vp->v_op = &dead_vnodeops; 1129 vgone(vp); 1130 vput(vp); 1131 } 1132 1133 /* 1134 * Insert into list of vnodes for the new mount point, if available. 1135 */ 1136 int 1137 insmntque1(struct vnode *vp, struct mount *mp, 1138 void (*dtr)(struct vnode *, void *), void *dtr_arg) 1139 { 1140 1141 KASSERT(vp->v_mount == NULL, 1142 ("insmntque: vnode already on per mount vnode list")); 1143 VNASSERT(mp != NULL, vp, ("Don't call insmntque(foo, NULL)")); 1144 ASSERT_VOP_ELOCKED(vp, "insmntque: non-locked vp"); 1145 1146 /* 1147 * We acquire the vnode interlock early to ensure that the 1148 * vnode cannot be recycled by another process releasing a 1149 * holdcnt on it before we get it on both the vnode list 1150 * and the active vnode list. The mount mutex protects only 1151 * manipulation of the vnode list and the vnode freelist 1152 * mutex protects only manipulation of the active vnode list. 1153 * Hence the need to hold the vnode interlock throughout. 1154 */ 1155 MNT_ILOCK(mp); 1156 VI_LOCK(vp); 1157 if (((mp->mnt_kern_flag & MNTK_NOINSMNTQ) != 0 && 1158 ((mp->mnt_kern_flag & MNTK_UNMOUNTF) != 0 || 1159 mp->mnt_nvnodelistsize == 0)) && 1160 (vp->v_vflag & VV_FORCEINSMQ) == 0) { 1161 VI_UNLOCK(vp); 1162 MNT_IUNLOCK(mp); 1163 if (dtr != NULL) 1164 dtr(vp, dtr_arg); 1165 return (EBUSY); 1166 } 1167 vp->v_mount = mp; 1168 MNT_REF(mp); 1169 TAILQ_INSERT_TAIL(&mp->mnt_nvnodelist, vp, v_nmntvnodes); 1170 VNASSERT(mp->mnt_nvnodelistsize >= 0, vp, 1171 ("neg mount point vnode list size")); 1172 mp->mnt_nvnodelistsize++; 1173 KASSERT((vp->v_iflag & VI_ACTIVE) == 0, 1174 ("Activating already active vnode")); 1175 vp->v_iflag |= VI_ACTIVE; 1176 mtx_lock(&vnode_free_list_mtx); 1177 TAILQ_INSERT_HEAD(&mp->mnt_activevnodelist, vp, v_actfreelist); 1178 mp->mnt_activevnodelistsize++; 1179 mtx_unlock(&vnode_free_list_mtx); 1180 VI_UNLOCK(vp); 1181 MNT_IUNLOCK(mp); 1182 return (0); 1183 } 1184 1185 int 1186 insmntque(struct vnode *vp, struct mount *mp) 1187 { 1188 1189 return (insmntque1(vp, mp, insmntque_stddtr, NULL)); 1190 } 1191 1192 /* 1193 * Flush out and invalidate all buffers associated with a bufobj 1194 * Called with the underlying object locked. 1195 */ 1196 int 1197 bufobj_invalbuf(struct bufobj *bo, int flags, int slpflag, int slptimeo) 1198 { 1199 int error; 1200 1201 BO_LOCK(bo); 1202 if (flags & V_SAVE) { 1203 error = bufobj_wwait(bo, slpflag, slptimeo); 1204 if (error) { 1205 BO_UNLOCK(bo); 1206 return (error); 1207 } 1208 if (bo->bo_dirty.bv_cnt > 0) { 1209 BO_UNLOCK(bo); 1210 if ((error = BO_SYNC(bo, MNT_WAIT)) != 0) 1211 return (error); 1212 /* 1213 * XXX We could save a lock/unlock if this was only 1214 * enabled under INVARIANTS 1215 */ 1216 BO_LOCK(bo); 1217 if (bo->bo_numoutput > 0 || bo->bo_dirty.bv_cnt > 0) 1218 panic("vinvalbuf: dirty bufs"); 1219 } 1220 } 1221 /* 1222 * If you alter this loop please notice that interlock is dropped and 1223 * reacquired in flushbuflist. Special care is needed to ensure that 1224 * no race conditions occur from this. 1225 */ 1226 do { 1227 error = flushbuflist(&bo->bo_clean, 1228 flags, bo, slpflag, slptimeo); 1229 if (error == 0 && !(flags & V_CLEANONLY)) 1230 error = flushbuflist(&bo->bo_dirty, 1231 flags, bo, slpflag, slptimeo); 1232 if (error != 0 && error != EAGAIN) { 1233 BO_UNLOCK(bo); 1234 return (error); 1235 } 1236 } while (error != 0); 1237 1238 /* 1239 * Wait for I/O to complete. XXX needs cleaning up. The vnode can 1240 * have write I/O in-progress but if there is a VM object then the 1241 * VM object can also have read-I/O in-progress. 1242 */ 1243 do { 1244 bufobj_wwait(bo, 0, 0); 1245 BO_UNLOCK(bo); 1246 if (bo->bo_object != NULL) { 1247 VM_OBJECT_LOCK(bo->bo_object); 1248 vm_object_pip_wait(bo->bo_object, "bovlbx"); 1249 VM_OBJECT_UNLOCK(bo->bo_object); 1250 } 1251 BO_LOCK(bo); 1252 } while (bo->bo_numoutput > 0); 1253 BO_UNLOCK(bo); 1254 1255 /* 1256 * Destroy the copy in the VM cache, too. 1257 */ 1258 if (bo->bo_object != NULL && 1259 (flags & (V_ALT | V_NORMAL | V_CLEANONLY)) == 0) { 1260 VM_OBJECT_LOCK(bo->bo_object); 1261 vm_object_page_remove(bo->bo_object, 0, 0, (flags & V_SAVE) ? 1262 OBJPR_CLEANONLY : 0); 1263 VM_OBJECT_UNLOCK(bo->bo_object); 1264 } 1265 1266 #ifdef INVARIANTS 1267 BO_LOCK(bo); 1268 if ((flags & (V_ALT | V_NORMAL | V_CLEANONLY)) == 0 && 1269 (bo->bo_dirty.bv_cnt > 0 || bo->bo_clean.bv_cnt > 0)) 1270 panic("vinvalbuf: flush failed"); 1271 BO_UNLOCK(bo); 1272 #endif 1273 return (0); 1274 } 1275 1276 /* 1277 * Flush out and invalidate all buffers associated with a vnode. 1278 * Called with the underlying object locked. 1279 */ 1280 int 1281 vinvalbuf(struct vnode *vp, int flags, int slpflag, int slptimeo) 1282 { 1283 1284 CTR3(KTR_VFS, "%s: vp %p with flags %d", __func__, vp, flags); 1285 ASSERT_VOP_LOCKED(vp, "vinvalbuf"); 1286 return (bufobj_invalbuf(&vp->v_bufobj, flags, slpflag, slptimeo)); 1287 } 1288 1289 /* 1290 * Flush out buffers on the specified list. 1291 * 1292 */ 1293 static int 1294 flushbuflist(struct bufv *bufv, int flags, struct bufobj *bo, int slpflag, 1295 int slptimeo) 1296 { 1297 struct buf *bp, *nbp; 1298 int retval, error; 1299 daddr_t lblkno; 1300 b_xflags_t xflags; 1301 1302 ASSERT_BO_LOCKED(bo); 1303 1304 retval = 0; 1305 TAILQ_FOREACH_SAFE(bp, &bufv->bv_hd, b_bobufs, nbp) { 1306 if (((flags & V_NORMAL) && (bp->b_xflags & BX_ALTDATA)) || 1307 ((flags & V_ALT) && (bp->b_xflags & BX_ALTDATA) == 0)) { 1308 continue; 1309 } 1310 lblkno = 0; 1311 xflags = 0; 1312 if (nbp != NULL) { 1313 lblkno = nbp->b_lblkno; 1314 xflags = nbp->b_xflags & 1315 (BX_BKGRDMARKER | BX_VNDIRTY | BX_VNCLEAN); 1316 } 1317 retval = EAGAIN; 1318 error = BUF_TIMELOCK(bp, 1319 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, BO_MTX(bo), 1320 "flushbuf", slpflag, slptimeo); 1321 if (error) { 1322 BO_LOCK(bo); 1323 return (error != ENOLCK ? error : EAGAIN); 1324 } 1325 KASSERT(bp->b_bufobj == bo, 1326 ("bp %p wrong b_bufobj %p should be %p", 1327 bp, bp->b_bufobj, bo)); 1328 if (bp->b_bufobj != bo) { /* XXX: necessary ? */ 1329 BUF_UNLOCK(bp); 1330 BO_LOCK(bo); 1331 return (EAGAIN); 1332 } 1333 /* 1334 * XXX Since there are no node locks for NFS, I 1335 * believe there is a slight chance that a delayed 1336 * write will occur while sleeping just above, so 1337 * check for it. 1338 */ 1339 if (((bp->b_flags & (B_DELWRI | B_INVAL)) == B_DELWRI) && 1340 (flags & V_SAVE)) { 1341 BO_LOCK(bo); 1342 bremfree(bp); 1343 BO_UNLOCK(bo); 1344 bp->b_flags |= B_ASYNC; 1345 bwrite(bp); 1346 BO_LOCK(bo); 1347 return (EAGAIN); /* XXX: why not loop ? */ 1348 } 1349 BO_LOCK(bo); 1350 bremfree(bp); 1351 BO_UNLOCK(bo); 1352 bp->b_flags |= (B_INVAL | B_RELBUF); 1353 bp->b_flags &= ~B_ASYNC; 1354 brelse(bp); 1355 BO_LOCK(bo); 1356 if (nbp != NULL && 1357 (nbp->b_bufobj != bo || 1358 nbp->b_lblkno != lblkno || 1359 (nbp->b_xflags & 1360 (BX_BKGRDMARKER | BX_VNDIRTY | BX_VNCLEAN)) != xflags)) 1361 break; /* nbp invalid */ 1362 } 1363 return (retval); 1364 } 1365 1366 /* 1367 * Truncate a file's buffer and pages to a specified length. This 1368 * is in lieu of the old vinvalbuf mechanism, which performed unneeded 1369 * sync activity. 1370 */ 1371 int 1372 vtruncbuf(struct vnode *vp, struct ucred *cred, off_t length, int blksize) 1373 { 1374 struct buf *bp, *nbp; 1375 int anyfreed; 1376 int trunclbn; 1377 struct bufobj *bo; 1378 1379 CTR5(KTR_VFS, "%s: vp %p with cred %p and block %d:%ju", __func__, 1380 vp, cred, blksize, (uintmax_t)length); 1381 1382 /* 1383 * Round up to the *next* lbn. 1384 */ 1385 trunclbn = (length + blksize - 1) / blksize; 1386 1387 ASSERT_VOP_LOCKED(vp, "vtruncbuf"); 1388 restart: 1389 bo = &vp->v_bufobj; 1390 BO_LOCK(bo); 1391 anyfreed = 1; 1392 for (;anyfreed;) { 1393 anyfreed = 0; 1394 TAILQ_FOREACH_SAFE(bp, &bo->bo_clean.bv_hd, b_bobufs, nbp) { 1395 if (bp->b_lblkno < trunclbn) 1396 continue; 1397 if (BUF_LOCK(bp, 1398 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, 1399 BO_MTX(bo)) == ENOLCK) 1400 goto restart; 1401 1402 BO_LOCK(bo); 1403 bremfree(bp); 1404 BO_UNLOCK(bo); 1405 bp->b_flags |= (B_INVAL | B_RELBUF); 1406 bp->b_flags &= ~B_ASYNC; 1407 brelse(bp); 1408 anyfreed = 1; 1409 1410 BO_LOCK(bo); 1411 if (nbp != NULL && 1412 (((nbp->b_xflags & BX_VNCLEAN) == 0) || 1413 (nbp->b_vp != vp) || 1414 (nbp->b_flags & B_DELWRI))) { 1415 BO_UNLOCK(bo); 1416 goto restart; 1417 } 1418 } 1419 1420 TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) { 1421 if (bp->b_lblkno < trunclbn) 1422 continue; 1423 if (BUF_LOCK(bp, 1424 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, 1425 BO_MTX(bo)) == ENOLCK) 1426 goto restart; 1427 BO_LOCK(bo); 1428 bremfree(bp); 1429 BO_UNLOCK(bo); 1430 bp->b_flags |= (B_INVAL | B_RELBUF); 1431 bp->b_flags &= ~B_ASYNC; 1432 brelse(bp); 1433 anyfreed = 1; 1434 1435 BO_LOCK(bo); 1436 if (nbp != NULL && 1437 (((nbp->b_xflags & BX_VNDIRTY) == 0) || 1438 (nbp->b_vp != vp) || 1439 (nbp->b_flags & B_DELWRI) == 0)) { 1440 BO_UNLOCK(bo); 1441 goto restart; 1442 } 1443 } 1444 } 1445 1446 if (length > 0) { 1447 restartsync: 1448 TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) { 1449 if (bp->b_lblkno > 0) 1450 continue; 1451 /* 1452 * Since we hold the vnode lock this should only 1453 * fail if we're racing with the buf daemon. 1454 */ 1455 if (BUF_LOCK(bp, 1456 LK_EXCLUSIVE | LK_SLEEPFAIL | LK_INTERLOCK, 1457 BO_MTX(bo)) == ENOLCK) { 1458 goto restart; 1459 } 1460 VNASSERT((bp->b_flags & B_DELWRI), vp, 1461 ("buf(%p) on dirty queue without DELWRI", bp)); 1462 1463 BO_LOCK(bo); 1464 bremfree(bp); 1465 BO_UNLOCK(bo); 1466 bawrite(bp); 1467 BO_LOCK(bo); 1468 goto restartsync; 1469 } 1470 } 1471 1472 bufobj_wwait(bo, 0, 0); 1473 BO_UNLOCK(bo); 1474 vnode_pager_setsize(vp, length); 1475 1476 return (0); 1477 } 1478 1479 /* 1480 * buf_splay() - splay tree core for the clean/dirty list of buffers in 1481 * a vnode. 1482 * 1483 * NOTE: We have to deal with the special case of a background bitmap 1484 * buffer, a situation where two buffers will have the same logical 1485 * block offset. We want (1) only the foreground buffer to be accessed 1486 * in a lookup and (2) must differentiate between the foreground and 1487 * background buffer in the splay tree algorithm because the splay 1488 * tree cannot normally handle multiple entities with the same 'index'. 1489 * We accomplish this by adding differentiating flags to the splay tree's 1490 * numerical domain. 1491 */ 1492 static 1493 struct buf * 1494 buf_splay(daddr_t lblkno, b_xflags_t xflags, struct buf *root) 1495 { 1496 struct buf dummy; 1497 struct buf *lefttreemax, *righttreemin, *y; 1498 1499 if (root == NULL) 1500 return (NULL); 1501 lefttreemax = righttreemin = &dummy; 1502 for (;;) { 1503 if (lblkno < root->b_lblkno || 1504 (lblkno == root->b_lblkno && 1505 (xflags & BX_BKGRDMARKER) < (root->b_xflags & BX_BKGRDMARKER))) { 1506 if ((y = root->b_left) == NULL) 1507 break; 1508 if (lblkno < y->b_lblkno) { 1509 /* Rotate right. */ 1510 root->b_left = y->b_right; 1511 y->b_right = root; 1512 root = y; 1513 if ((y = root->b_left) == NULL) 1514 break; 1515 } 1516 /* Link into the new root's right tree. */ 1517 righttreemin->b_left = root; 1518 righttreemin = root; 1519 } else if (lblkno > root->b_lblkno || 1520 (lblkno == root->b_lblkno && 1521 (xflags & BX_BKGRDMARKER) > (root->b_xflags & BX_BKGRDMARKER))) { 1522 if ((y = root->b_right) == NULL) 1523 break; 1524 if (lblkno > y->b_lblkno) { 1525 /* Rotate left. */ 1526 root->b_right = y->b_left; 1527 y->b_left = root; 1528 root = y; 1529 if ((y = root->b_right) == NULL) 1530 break; 1531 } 1532 /* Link into the new root's left tree. */ 1533 lefttreemax->b_right = root; 1534 lefttreemax = root; 1535 } else { 1536 break; 1537 } 1538 root = y; 1539 } 1540 /* Assemble the new root. */ 1541 lefttreemax->b_right = root->b_left; 1542 righttreemin->b_left = root->b_right; 1543 root->b_left = dummy.b_right; 1544 root->b_right = dummy.b_left; 1545 return (root); 1546 } 1547 1548 static void 1549 buf_vlist_remove(struct buf *bp) 1550 { 1551 struct buf *root; 1552 struct bufv *bv; 1553 1554 KASSERT(bp->b_bufobj != NULL, ("No b_bufobj %p", bp)); 1555 ASSERT_BO_LOCKED(bp->b_bufobj); 1556 KASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) != 1557 (BX_VNDIRTY|BX_VNCLEAN), 1558 ("buf_vlist_remove: Buf %p is on two lists", bp)); 1559 if (bp->b_xflags & BX_VNDIRTY) 1560 bv = &bp->b_bufobj->bo_dirty; 1561 else 1562 bv = &bp->b_bufobj->bo_clean; 1563 if (bp != bv->bv_root) { 1564 root = buf_splay(bp->b_lblkno, bp->b_xflags, bv->bv_root); 1565 KASSERT(root == bp, ("splay lookup failed in remove")); 1566 } 1567 if (bp->b_left == NULL) { 1568 root = bp->b_right; 1569 } else { 1570 root = buf_splay(bp->b_lblkno, bp->b_xflags, bp->b_left); 1571 root->b_right = bp->b_right; 1572 } 1573 bv->bv_root = root; 1574 TAILQ_REMOVE(&bv->bv_hd, bp, b_bobufs); 1575 bv->bv_cnt--; 1576 bp->b_xflags &= ~(BX_VNDIRTY | BX_VNCLEAN); 1577 } 1578 1579 /* 1580 * Add the buffer to the sorted clean or dirty block list using a 1581 * splay tree algorithm. 1582 * 1583 * NOTE: xflags is passed as a constant, optimizing this inline function! 1584 */ 1585 static void 1586 buf_vlist_add(struct buf *bp, struct bufobj *bo, b_xflags_t xflags) 1587 { 1588 struct buf *root; 1589 struct bufv *bv; 1590 1591 ASSERT_BO_LOCKED(bo); 1592 KASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) == 0, 1593 ("buf_vlist_add: Buf %p has existing xflags %d", bp, bp->b_xflags)); 1594 bp->b_xflags |= xflags; 1595 if (xflags & BX_VNDIRTY) 1596 bv = &bo->bo_dirty; 1597 else 1598 bv = &bo->bo_clean; 1599 1600 root = buf_splay(bp->b_lblkno, bp->b_xflags, bv->bv_root); 1601 if (root == NULL) { 1602 bp->b_left = NULL; 1603 bp->b_right = NULL; 1604 TAILQ_INSERT_TAIL(&bv->bv_hd, bp, b_bobufs); 1605 } else if (bp->b_lblkno < root->b_lblkno || 1606 (bp->b_lblkno == root->b_lblkno && 1607 (bp->b_xflags & BX_BKGRDMARKER) < (root->b_xflags & BX_BKGRDMARKER))) { 1608 bp->b_left = root->b_left; 1609 bp->b_right = root; 1610 root->b_left = NULL; 1611 TAILQ_INSERT_BEFORE(root, bp, b_bobufs); 1612 } else { 1613 bp->b_right = root->b_right; 1614 bp->b_left = root; 1615 root->b_right = NULL; 1616 TAILQ_INSERT_AFTER(&bv->bv_hd, root, bp, b_bobufs); 1617 } 1618 bv->bv_cnt++; 1619 bv->bv_root = bp; 1620 } 1621 1622 /* 1623 * Lookup a buffer using the splay tree. Note that we specifically avoid 1624 * shadow buffers used in background bitmap writes. 1625 * 1626 * This code isn't quite efficient as it could be because we are maintaining 1627 * two sorted lists and do not know which list the block resides in. 1628 * 1629 * During a "make buildworld" the desired buffer is found at one of 1630 * the roots more than 60% of the time. Thus, checking both roots 1631 * before performing either splay eliminates unnecessary splays on the 1632 * first tree splayed. 1633 */ 1634 struct buf * 1635 gbincore(struct bufobj *bo, daddr_t lblkno) 1636 { 1637 struct buf *bp; 1638 1639 ASSERT_BO_LOCKED(bo); 1640 if ((bp = bo->bo_clean.bv_root) != NULL && 1641 bp->b_lblkno == lblkno && !(bp->b_xflags & BX_BKGRDMARKER)) 1642 return (bp); 1643 if ((bp = bo->bo_dirty.bv_root) != NULL && 1644 bp->b_lblkno == lblkno && !(bp->b_xflags & BX_BKGRDMARKER)) 1645 return (bp); 1646 if ((bp = bo->bo_clean.bv_root) != NULL) { 1647 bo->bo_clean.bv_root = bp = buf_splay(lblkno, 0, bp); 1648 if (bp->b_lblkno == lblkno && !(bp->b_xflags & BX_BKGRDMARKER)) 1649 return (bp); 1650 } 1651 if ((bp = bo->bo_dirty.bv_root) != NULL) { 1652 bo->bo_dirty.bv_root = bp = buf_splay(lblkno, 0, bp); 1653 if (bp->b_lblkno == lblkno && !(bp->b_xflags & BX_BKGRDMARKER)) 1654 return (bp); 1655 } 1656 return (NULL); 1657 } 1658 1659 /* 1660 * Associate a buffer with a vnode. 1661 */ 1662 void 1663 bgetvp(struct vnode *vp, struct buf *bp) 1664 { 1665 struct bufobj *bo; 1666 1667 bo = &vp->v_bufobj; 1668 ASSERT_BO_LOCKED(bo); 1669 VNASSERT(bp->b_vp == NULL, bp->b_vp, ("bgetvp: not free")); 1670 1671 CTR3(KTR_BUF, "bgetvp(%p) vp %p flags %X", bp, vp, bp->b_flags); 1672 VNASSERT((bp->b_xflags & (BX_VNDIRTY|BX_VNCLEAN)) == 0, vp, 1673 ("bgetvp: bp already attached! %p", bp)); 1674 1675 vhold(vp); 1676 bp->b_vp = vp; 1677 bp->b_bufobj = bo; 1678 /* 1679 * Insert onto list for new vnode. 1680 */ 1681 buf_vlist_add(bp, bo, BX_VNCLEAN); 1682 } 1683 1684 /* 1685 * Disassociate a buffer from a vnode. 1686 */ 1687 void 1688 brelvp(struct buf *bp) 1689 { 1690 struct bufobj *bo; 1691 struct vnode *vp; 1692 1693 CTR3(KTR_BUF, "brelvp(%p) vp %p flags %X", bp, bp->b_vp, bp->b_flags); 1694 KASSERT(bp->b_vp != NULL, ("brelvp: NULL")); 1695 1696 /* 1697 * Delete from old vnode list, if on one. 1698 */ 1699 vp = bp->b_vp; /* XXX */ 1700 bo = bp->b_bufobj; 1701 BO_LOCK(bo); 1702 if (bp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN)) 1703 buf_vlist_remove(bp); 1704 else 1705 panic("brelvp: Buffer %p not on queue.", bp); 1706 if ((bo->bo_flag & BO_ONWORKLST) && bo->bo_dirty.bv_cnt == 0) { 1707 bo->bo_flag &= ~BO_ONWORKLST; 1708 mtx_lock(&sync_mtx); 1709 LIST_REMOVE(bo, bo_synclist); 1710 syncer_worklist_len--; 1711 mtx_unlock(&sync_mtx); 1712 } 1713 bp->b_vp = NULL; 1714 bp->b_bufobj = NULL; 1715 BO_UNLOCK(bo); 1716 vdrop(vp); 1717 } 1718 1719 /* 1720 * Add an item to the syncer work queue. 1721 */ 1722 static void 1723 vn_syncer_add_to_worklist(struct bufobj *bo, int delay) 1724 { 1725 int slot; 1726 1727 ASSERT_BO_LOCKED(bo); 1728 1729 mtx_lock(&sync_mtx); 1730 if (bo->bo_flag & BO_ONWORKLST) 1731 LIST_REMOVE(bo, bo_synclist); 1732 else { 1733 bo->bo_flag |= BO_ONWORKLST; 1734 syncer_worklist_len++; 1735 } 1736 1737 if (delay > syncer_maxdelay - 2) 1738 delay = syncer_maxdelay - 2; 1739 slot = (syncer_delayno + delay) & syncer_mask; 1740 1741 LIST_INSERT_HEAD(&syncer_workitem_pending[slot], bo, bo_synclist); 1742 mtx_unlock(&sync_mtx); 1743 } 1744 1745 static int 1746 sysctl_vfs_worklist_len(SYSCTL_HANDLER_ARGS) 1747 { 1748 int error, len; 1749 1750 mtx_lock(&sync_mtx); 1751 len = syncer_worklist_len - sync_vnode_count; 1752 mtx_unlock(&sync_mtx); 1753 error = SYSCTL_OUT(req, &len, sizeof(len)); 1754 return (error); 1755 } 1756 1757 SYSCTL_PROC(_vfs, OID_AUTO, worklist_len, CTLTYPE_INT | CTLFLAG_RD, NULL, 0, 1758 sysctl_vfs_worklist_len, "I", "Syncer thread worklist length"); 1759 1760 static struct proc *updateproc; 1761 static void sched_sync(void); 1762 static struct kproc_desc up_kp = { 1763 "syncer", 1764 sched_sync, 1765 &updateproc 1766 }; 1767 SYSINIT(syncer, SI_SUB_KTHREAD_UPDATE, SI_ORDER_FIRST, kproc_start, &up_kp); 1768 1769 static int 1770 sync_vnode(struct synclist *slp, struct bufobj **bo, struct thread *td) 1771 { 1772 struct vnode *vp; 1773 struct mount *mp; 1774 1775 *bo = LIST_FIRST(slp); 1776 if (*bo == NULL) 1777 return (0); 1778 vp = (*bo)->__bo_vnode; /* XXX */ 1779 if (VOP_ISLOCKED(vp) != 0 || VI_TRYLOCK(vp) == 0) 1780 return (1); 1781 /* 1782 * We use vhold in case the vnode does not 1783 * successfully sync. vhold prevents the vnode from 1784 * going away when we unlock the sync_mtx so that 1785 * we can acquire the vnode interlock. 1786 */ 1787 vholdl(vp); 1788 mtx_unlock(&sync_mtx); 1789 VI_UNLOCK(vp); 1790 if (vn_start_write(vp, &mp, V_NOWAIT) != 0) { 1791 vdrop(vp); 1792 mtx_lock(&sync_mtx); 1793 return (*bo == LIST_FIRST(slp)); 1794 } 1795 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 1796 (void) VOP_FSYNC(vp, MNT_LAZY, td); 1797 VOP_UNLOCK(vp, 0); 1798 vn_finished_write(mp); 1799 BO_LOCK(*bo); 1800 if (((*bo)->bo_flag & BO_ONWORKLST) != 0) { 1801 /* 1802 * Put us back on the worklist. The worklist 1803 * routine will remove us from our current 1804 * position and then add us back in at a later 1805 * position. 1806 */ 1807 vn_syncer_add_to_worklist(*bo, syncdelay); 1808 } 1809 BO_UNLOCK(*bo); 1810 vdrop(vp); 1811 mtx_lock(&sync_mtx); 1812 return (0); 1813 } 1814 1815 /* 1816 * System filesystem synchronizer daemon. 1817 */ 1818 static void 1819 sched_sync(void) 1820 { 1821 struct synclist *next, *slp; 1822 struct bufobj *bo; 1823 long starttime; 1824 struct thread *td = curthread; 1825 int last_work_seen; 1826 int net_worklist_len; 1827 int syncer_final_iter; 1828 int first_printf; 1829 int error; 1830 1831 last_work_seen = 0; 1832 syncer_final_iter = 0; 1833 first_printf = 1; 1834 syncer_state = SYNCER_RUNNING; 1835 starttime = time_uptime; 1836 td->td_pflags |= TDP_NORUNNINGBUF; 1837 1838 EVENTHANDLER_REGISTER(shutdown_pre_sync, syncer_shutdown, td->td_proc, 1839 SHUTDOWN_PRI_LAST); 1840 1841 mtx_lock(&sync_mtx); 1842 for (;;) { 1843 if (syncer_state == SYNCER_FINAL_DELAY && 1844 syncer_final_iter == 0) { 1845 mtx_unlock(&sync_mtx); 1846 kproc_suspend_check(td->td_proc); 1847 mtx_lock(&sync_mtx); 1848 } 1849 net_worklist_len = syncer_worklist_len - sync_vnode_count; 1850 if (syncer_state != SYNCER_RUNNING && 1851 starttime != time_uptime) { 1852 if (first_printf) { 1853 printf("\nSyncing disks, vnodes remaining..."); 1854 first_printf = 0; 1855 } 1856 printf("%d ", net_worklist_len); 1857 } 1858 starttime = time_uptime; 1859 1860 /* 1861 * Push files whose dirty time has expired. Be careful 1862 * of interrupt race on slp queue. 1863 * 1864 * Skip over empty worklist slots when shutting down. 1865 */ 1866 do { 1867 slp = &syncer_workitem_pending[syncer_delayno]; 1868 syncer_delayno += 1; 1869 if (syncer_delayno == syncer_maxdelay) 1870 syncer_delayno = 0; 1871 next = &syncer_workitem_pending[syncer_delayno]; 1872 /* 1873 * If the worklist has wrapped since the 1874 * it was emptied of all but syncer vnodes, 1875 * switch to the FINAL_DELAY state and run 1876 * for one more second. 1877 */ 1878 if (syncer_state == SYNCER_SHUTTING_DOWN && 1879 net_worklist_len == 0 && 1880 last_work_seen == syncer_delayno) { 1881 syncer_state = SYNCER_FINAL_DELAY; 1882 syncer_final_iter = SYNCER_SHUTDOWN_SPEEDUP; 1883 } 1884 } while (syncer_state != SYNCER_RUNNING && LIST_EMPTY(slp) && 1885 syncer_worklist_len > 0); 1886 1887 /* 1888 * Keep track of the last time there was anything 1889 * on the worklist other than syncer vnodes. 1890 * Return to the SHUTTING_DOWN state if any 1891 * new work appears. 1892 */ 1893 if (net_worklist_len > 0 || syncer_state == SYNCER_RUNNING) 1894 last_work_seen = syncer_delayno; 1895 if (net_worklist_len > 0 && syncer_state == SYNCER_FINAL_DELAY) 1896 syncer_state = SYNCER_SHUTTING_DOWN; 1897 while (!LIST_EMPTY(slp)) { 1898 error = sync_vnode(slp, &bo, td); 1899 if (error == 1) { 1900 LIST_REMOVE(bo, bo_synclist); 1901 LIST_INSERT_HEAD(next, bo, bo_synclist); 1902 continue; 1903 } 1904 1905 if (first_printf == 0) 1906 wdog_kern_pat(WD_LASTVAL); 1907 1908 } 1909 if (syncer_state == SYNCER_FINAL_DELAY && syncer_final_iter > 0) 1910 syncer_final_iter--; 1911 /* 1912 * The variable rushjob allows the kernel to speed up the 1913 * processing of the filesystem syncer process. A rushjob 1914 * value of N tells the filesystem syncer to process the next 1915 * N seconds worth of work on its queue ASAP. Currently rushjob 1916 * is used by the soft update code to speed up the filesystem 1917 * syncer process when the incore state is getting so far 1918 * ahead of the disk that the kernel memory pool is being 1919 * threatened with exhaustion. 1920 */ 1921 if (rushjob > 0) { 1922 rushjob -= 1; 1923 continue; 1924 } 1925 /* 1926 * Just sleep for a short period of time between 1927 * iterations when shutting down to allow some I/O 1928 * to happen. 1929 * 1930 * If it has taken us less than a second to process the 1931 * current work, then wait. Otherwise start right over 1932 * again. We can still lose time if any single round 1933 * takes more than two seconds, but it does not really 1934 * matter as we are just trying to generally pace the 1935 * filesystem activity. 1936 */ 1937 if (syncer_state != SYNCER_RUNNING || 1938 time_uptime == starttime) { 1939 thread_lock(td); 1940 sched_prio(td, PPAUSE); 1941 thread_unlock(td); 1942 } 1943 if (syncer_state != SYNCER_RUNNING) 1944 cv_timedwait(&sync_wakeup, &sync_mtx, 1945 hz / SYNCER_SHUTDOWN_SPEEDUP); 1946 else if (time_uptime == starttime) 1947 cv_timedwait(&sync_wakeup, &sync_mtx, hz); 1948 } 1949 } 1950 1951 /* 1952 * Request the syncer daemon to speed up its work. 1953 * We never push it to speed up more than half of its 1954 * normal turn time, otherwise it could take over the cpu. 1955 */ 1956 int 1957 speedup_syncer(void) 1958 { 1959 int ret = 0; 1960 1961 mtx_lock(&sync_mtx); 1962 if (rushjob < syncdelay / 2) { 1963 rushjob += 1; 1964 stat_rush_requests += 1; 1965 ret = 1; 1966 } 1967 mtx_unlock(&sync_mtx); 1968 cv_broadcast(&sync_wakeup); 1969 return (ret); 1970 } 1971 1972 /* 1973 * Tell the syncer to speed up its work and run though its work 1974 * list several times, then tell it to shut down. 1975 */ 1976 static void 1977 syncer_shutdown(void *arg, int howto) 1978 { 1979 1980 if (howto & RB_NOSYNC) 1981 return; 1982 mtx_lock(&sync_mtx); 1983 syncer_state = SYNCER_SHUTTING_DOWN; 1984 rushjob = 0; 1985 mtx_unlock(&sync_mtx); 1986 cv_broadcast(&sync_wakeup); 1987 kproc_shutdown(arg, howto); 1988 } 1989 1990 /* 1991 * Reassign a buffer from one vnode to another. 1992 * Used to assign file specific control information 1993 * (indirect blocks) to the vnode to which they belong. 1994 */ 1995 void 1996 reassignbuf(struct buf *bp) 1997 { 1998 struct vnode *vp; 1999 struct bufobj *bo; 2000 int delay; 2001 #ifdef INVARIANTS 2002 struct bufv *bv; 2003 #endif 2004 2005 vp = bp->b_vp; 2006 bo = bp->b_bufobj; 2007 ++reassignbufcalls; 2008 2009 CTR3(KTR_BUF, "reassignbuf(%p) vp %p flags %X", 2010 bp, bp->b_vp, bp->b_flags); 2011 /* 2012 * B_PAGING flagged buffers cannot be reassigned because their vp 2013 * is not fully linked in. 2014 */ 2015 if (bp->b_flags & B_PAGING) 2016 panic("cannot reassign paging buffer"); 2017 2018 /* 2019 * Delete from old vnode list, if on one. 2020 */ 2021 BO_LOCK(bo); 2022 if (bp->b_xflags & (BX_VNDIRTY | BX_VNCLEAN)) 2023 buf_vlist_remove(bp); 2024 else 2025 panic("reassignbuf: Buffer %p not on queue.", bp); 2026 /* 2027 * If dirty, put on list of dirty buffers; otherwise insert onto list 2028 * of clean buffers. 2029 */ 2030 if (bp->b_flags & B_DELWRI) { 2031 if ((bo->bo_flag & BO_ONWORKLST) == 0) { 2032 switch (vp->v_type) { 2033 case VDIR: 2034 delay = dirdelay; 2035 break; 2036 case VCHR: 2037 delay = metadelay; 2038 break; 2039 default: 2040 delay = filedelay; 2041 } 2042 vn_syncer_add_to_worklist(bo, delay); 2043 } 2044 buf_vlist_add(bp, bo, BX_VNDIRTY); 2045 } else { 2046 buf_vlist_add(bp, bo, BX_VNCLEAN); 2047 2048 if ((bo->bo_flag & BO_ONWORKLST) && bo->bo_dirty.bv_cnt == 0) { 2049 mtx_lock(&sync_mtx); 2050 LIST_REMOVE(bo, bo_synclist); 2051 syncer_worklist_len--; 2052 mtx_unlock(&sync_mtx); 2053 bo->bo_flag &= ~BO_ONWORKLST; 2054 } 2055 } 2056 #ifdef INVARIANTS 2057 bv = &bo->bo_clean; 2058 bp = TAILQ_FIRST(&bv->bv_hd); 2059 KASSERT(bp == NULL || bp->b_bufobj == bo, 2060 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 2061 bp = TAILQ_LAST(&bv->bv_hd, buflists); 2062 KASSERT(bp == NULL || bp->b_bufobj == bo, 2063 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 2064 bv = &bo->bo_dirty; 2065 bp = TAILQ_FIRST(&bv->bv_hd); 2066 KASSERT(bp == NULL || bp->b_bufobj == bo, 2067 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 2068 bp = TAILQ_LAST(&bv->bv_hd, buflists); 2069 KASSERT(bp == NULL || bp->b_bufobj == bo, 2070 ("bp %p wrong b_bufobj %p should be %p", bp, bp->b_bufobj, bo)); 2071 #endif 2072 BO_UNLOCK(bo); 2073 } 2074 2075 /* 2076 * Increment the use and hold counts on the vnode, taking care to reference 2077 * the driver's usecount if this is a chardev. The vholdl() will remove 2078 * the vnode from the free list if it is presently free. Requires the 2079 * vnode interlock and returns with it held. 2080 */ 2081 static void 2082 v_incr_usecount(struct vnode *vp) 2083 { 2084 2085 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2086 vp->v_usecount++; 2087 if (vp->v_type == VCHR && vp->v_rdev != NULL) { 2088 dev_lock(); 2089 vp->v_rdev->si_usecount++; 2090 dev_unlock(); 2091 } 2092 vholdl(vp); 2093 } 2094 2095 /* 2096 * Turn a holdcnt into a use+holdcnt such that only one call to 2097 * v_decr_usecount is needed. 2098 */ 2099 static void 2100 v_upgrade_usecount(struct vnode *vp) 2101 { 2102 2103 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2104 vp->v_usecount++; 2105 if (vp->v_type == VCHR && vp->v_rdev != NULL) { 2106 dev_lock(); 2107 vp->v_rdev->si_usecount++; 2108 dev_unlock(); 2109 } 2110 } 2111 2112 /* 2113 * Decrement the vnode use and hold count along with the driver's usecount 2114 * if this is a chardev. The vdropl() below releases the vnode interlock 2115 * as it may free the vnode. 2116 */ 2117 static void 2118 v_decr_usecount(struct vnode *vp) 2119 { 2120 2121 ASSERT_VI_LOCKED(vp, __FUNCTION__); 2122 VNASSERT(vp->v_usecount > 0, vp, 2123 ("v_decr_usecount: negative usecount")); 2124 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2125 vp->v_usecount--; 2126 if (vp->v_type == VCHR && vp->v_rdev != NULL) { 2127 dev_lock(); 2128 vp->v_rdev->si_usecount--; 2129 dev_unlock(); 2130 } 2131 vdropl(vp); 2132 } 2133 2134 /* 2135 * Decrement only the use count and driver use count. This is intended to 2136 * be paired with a follow on vdropl() to release the remaining hold count. 2137 * In this way we may vgone() a vnode with a 0 usecount without risk of 2138 * having it end up on a free list because the hold count is kept above 0. 2139 */ 2140 static void 2141 v_decr_useonly(struct vnode *vp) 2142 { 2143 2144 ASSERT_VI_LOCKED(vp, __FUNCTION__); 2145 VNASSERT(vp->v_usecount > 0, vp, 2146 ("v_decr_useonly: negative usecount")); 2147 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2148 vp->v_usecount--; 2149 if (vp->v_type == VCHR && vp->v_rdev != NULL) { 2150 dev_lock(); 2151 vp->v_rdev->si_usecount--; 2152 dev_unlock(); 2153 } 2154 } 2155 2156 /* 2157 * Grab a particular vnode from the free list, increment its 2158 * reference count and lock it. VI_DOOMED is set if the vnode 2159 * is being destroyed. Only callers who specify LK_RETRY will 2160 * see doomed vnodes. If inactive processing was delayed in 2161 * vput try to do it here. 2162 */ 2163 int 2164 vget(struct vnode *vp, int flags, struct thread *td) 2165 { 2166 int error; 2167 2168 error = 0; 2169 VNASSERT((flags & LK_TYPE_MASK) != 0, vp, 2170 ("vget: invalid lock operation")); 2171 CTR3(KTR_VFS, "%s: vp %p with flags %d", __func__, vp, flags); 2172 2173 if ((flags & LK_INTERLOCK) == 0) 2174 VI_LOCK(vp); 2175 vholdl(vp); 2176 if ((error = vn_lock(vp, flags | LK_INTERLOCK)) != 0) { 2177 vdrop(vp); 2178 CTR2(KTR_VFS, "%s: impossible to lock vnode %p", __func__, 2179 vp); 2180 return (error); 2181 } 2182 if (vp->v_iflag & VI_DOOMED && (flags & LK_RETRY) == 0) 2183 panic("vget: vn_lock failed to return ENOENT\n"); 2184 VI_LOCK(vp); 2185 /* Upgrade our holdcnt to a usecount. */ 2186 v_upgrade_usecount(vp); 2187 /* 2188 * We don't guarantee that any particular close will 2189 * trigger inactive processing so just make a best effort 2190 * here at preventing a reference to a removed file. If 2191 * we don't succeed no harm is done. 2192 */ 2193 if (vp->v_iflag & VI_OWEINACT) { 2194 if (VOP_ISLOCKED(vp) == LK_EXCLUSIVE && 2195 (flags & LK_NOWAIT) == 0) 2196 vinactive(vp, td); 2197 vp->v_iflag &= ~VI_OWEINACT; 2198 } 2199 VI_UNLOCK(vp); 2200 return (0); 2201 } 2202 2203 /* 2204 * Increase the reference count of a vnode. 2205 */ 2206 void 2207 vref(struct vnode *vp) 2208 { 2209 2210 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2211 VI_LOCK(vp); 2212 v_incr_usecount(vp); 2213 VI_UNLOCK(vp); 2214 } 2215 2216 /* 2217 * Return reference count of a vnode. 2218 * 2219 * The results of this call are only guaranteed when some mechanism other 2220 * than the VI lock is used to stop other processes from gaining references 2221 * to the vnode. This may be the case if the caller holds the only reference. 2222 * This is also useful when stale data is acceptable as race conditions may 2223 * be accounted for by some other means. 2224 */ 2225 int 2226 vrefcnt(struct vnode *vp) 2227 { 2228 int usecnt; 2229 2230 VI_LOCK(vp); 2231 usecnt = vp->v_usecount; 2232 VI_UNLOCK(vp); 2233 2234 return (usecnt); 2235 } 2236 2237 #define VPUTX_VRELE 1 2238 #define VPUTX_VPUT 2 2239 #define VPUTX_VUNREF 3 2240 2241 static void 2242 vputx(struct vnode *vp, int func) 2243 { 2244 int error; 2245 2246 KASSERT(vp != NULL, ("vputx: null vp")); 2247 if (func == VPUTX_VUNREF) 2248 ASSERT_VOP_LOCKED(vp, "vunref"); 2249 else if (func == VPUTX_VPUT) 2250 ASSERT_VOP_LOCKED(vp, "vput"); 2251 else 2252 KASSERT(func == VPUTX_VRELE, ("vputx: wrong func")); 2253 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2254 VI_LOCK(vp); 2255 2256 /* Skip this v_writecount check if we're going to panic below. */ 2257 VNASSERT(vp->v_writecount < vp->v_usecount || vp->v_usecount < 1, vp, 2258 ("vputx: missed vn_close")); 2259 error = 0; 2260 2261 if (vp->v_usecount > 1 || ((vp->v_iflag & VI_DOINGINACT) && 2262 vp->v_usecount == 1)) { 2263 if (func == VPUTX_VPUT) 2264 VOP_UNLOCK(vp, 0); 2265 v_decr_usecount(vp); 2266 return; 2267 } 2268 2269 if (vp->v_usecount != 1) { 2270 vprint("vputx: negative ref count", vp); 2271 panic("vputx: negative ref cnt"); 2272 } 2273 CTR2(KTR_VFS, "%s: return vnode %p to the freelist", __func__, vp); 2274 /* 2275 * We want to hold the vnode until the inactive finishes to 2276 * prevent vgone() races. We drop the use count here and the 2277 * hold count below when we're done. 2278 */ 2279 v_decr_useonly(vp); 2280 /* 2281 * We must call VOP_INACTIVE with the node locked. Mark 2282 * as VI_DOINGINACT to avoid recursion. 2283 */ 2284 vp->v_iflag |= VI_OWEINACT; 2285 switch (func) { 2286 case VPUTX_VRELE: 2287 error = vn_lock(vp, LK_EXCLUSIVE | LK_INTERLOCK); 2288 VI_LOCK(vp); 2289 break; 2290 case VPUTX_VPUT: 2291 if (VOP_ISLOCKED(vp) != LK_EXCLUSIVE) { 2292 error = VOP_LOCK(vp, LK_UPGRADE | LK_INTERLOCK | 2293 LK_NOWAIT); 2294 VI_LOCK(vp); 2295 } 2296 break; 2297 case VPUTX_VUNREF: 2298 if (VOP_ISLOCKED(vp) != LK_EXCLUSIVE) 2299 error = EBUSY; 2300 break; 2301 } 2302 if (vp->v_usecount > 0) 2303 vp->v_iflag &= ~VI_OWEINACT; 2304 if (error == 0) { 2305 if (vp->v_iflag & VI_OWEINACT) 2306 vinactive(vp, curthread); 2307 if (func != VPUTX_VUNREF) 2308 VOP_UNLOCK(vp, 0); 2309 } 2310 vdropl(vp); 2311 } 2312 2313 /* 2314 * Vnode put/release. 2315 * If count drops to zero, call inactive routine and return to freelist. 2316 */ 2317 void 2318 vrele(struct vnode *vp) 2319 { 2320 2321 vputx(vp, VPUTX_VRELE); 2322 } 2323 2324 /* 2325 * Release an already locked vnode. This give the same effects as 2326 * unlock+vrele(), but takes less time and avoids releasing and 2327 * re-aquiring the lock (as vrele() acquires the lock internally.) 2328 */ 2329 void 2330 vput(struct vnode *vp) 2331 { 2332 2333 vputx(vp, VPUTX_VPUT); 2334 } 2335 2336 /* 2337 * Release an exclusively locked vnode. Do not unlock the vnode lock. 2338 */ 2339 void 2340 vunref(struct vnode *vp) 2341 { 2342 2343 vputx(vp, VPUTX_VUNREF); 2344 } 2345 2346 /* 2347 * Somebody doesn't want the vnode recycled. 2348 */ 2349 void 2350 vhold(struct vnode *vp) 2351 { 2352 2353 VI_LOCK(vp); 2354 vholdl(vp); 2355 VI_UNLOCK(vp); 2356 } 2357 2358 /* 2359 * Increase the hold count and activate if this is the first reference. 2360 */ 2361 void 2362 vholdl(struct vnode *vp) 2363 { 2364 struct mount *mp; 2365 2366 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2367 vp->v_holdcnt++; 2368 if (!VSHOULDBUSY(vp)) 2369 return; 2370 ASSERT_VI_LOCKED(vp, "vholdl"); 2371 VNASSERT((vp->v_iflag & VI_FREE) != 0, vp, ("vnode not free")); 2372 VNASSERT(vp->v_op != NULL, vp, ("vholdl: vnode already reclaimed.")); 2373 /* 2374 * Remove a vnode from the free list, mark it as in use, 2375 * and put it on the active list. 2376 */ 2377 mtx_lock(&vnode_free_list_mtx); 2378 TAILQ_REMOVE(&vnode_free_list, vp, v_actfreelist); 2379 freevnodes--; 2380 vp->v_iflag &= ~(VI_FREE|VI_AGE); 2381 KASSERT((vp->v_iflag & VI_ACTIVE) == 0, 2382 ("Activating already active vnode")); 2383 vp->v_iflag |= VI_ACTIVE; 2384 mp = vp->v_mount; 2385 TAILQ_INSERT_HEAD(&mp->mnt_activevnodelist, vp, v_actfreelist); 2386 mp->mnt_activevnodelistsize++; 2387 mtx_unlock(&vnode_free_list_mtx); 2388 } 2389 2390 /* 2391 * Note that there is one less who cares about this vnode. 2392 * vdrop() is the opposite of vhold(). 2393 */ 2394 void 2395 vdrop(struct vnode *vp) 2396 { 2397 2398 VI_LOCK(vp); 2399 vdropl(vp); 2400 } 2401 2402 /* 2403 * Drop the hold count of the vnode. If this is the last reference to 2404 * the vnode we place it on the free list unless it has been vgone'd 2405 * (marked VI_DOOMED) in which case we will free it. 2406 */ 2407 void 2408 vdropl(struct vnode *vp) 2409 { 2410 struct bufobj *bo; 2411 struct mount *mp; 2412 int active; 2413 2414 ASSERT_VI_LOCKED(vp, "vdropl"); 2415 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2416 if (vp->v_holdcnt <= 0) 2417 panic("vdrop: holdcnt %d", vp->v_holdcnt); 2418 vp->v_holdcnt--; 2419 if (vp->v_holdcnt > 0) { 2420 VI_UNLOCK(vp); 2421 return; 2422 } 2423 if ((vp->v_iflag & VI_DOOMED) == 0) { 2424 /* 2425 * Mark a vnode as free: remove it from its active list 2426 * and put it up for recycling on the freelist. 2427 */ 2428 VNASSERT(vp->v_op != NULL, vp, 2429 ("vdropl: vnode already reclaimed.")); 2430 VNASSERT((vp->v_iflag & VI_FREE) == 0, vp, 2431 ("vnode already free")); 2432 VNASSERT(VSHOULDFREE(vp), vp, 2433 ("vdropl: freeing when we shouldn't")); 2434 active = vp->v_iflag & VI_ACTIVE; 2435 vp->v_iflag &= ~VI_ACTIVE; 2436 mp = vp->v_mount; 2437 mtx_lock(&vnode_free_list_mtx); 2438 if (active) { 2439 TAILQ_REMOVE(&mp->mnt_activevnodelist, vp, 2440 v_actfreelist); 2441 mp->mnt_activevnodelistsize--; 2442 } 2443 if (vp->v_iflag & VI_AGE) { 2444 TAILQ_INSERT_HEAD(&vnode_free_list, vp, v_actfreelist); 2445 } else { 2446 TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_actfreelist); 2447 } 2448 freevnodes++; 2449 vp->v_iflag &= ~VI_AGE; 2450 vp->v_iflag |= VI_FREE; 2451 mtx_unlock(&vnode_free_list_mtx); 2452 VI_UNLOCK(vp); 2453 return; 2454 } 2455 /* 2456 * The vnode has been marked for destruction, so free it. 2457 */ 2458 CTR2(KTR_VFS, "%s: destroying the vnode %p", __func__, vp); 2459 mtx_lock(&vnode_free_list_mtx); 2460 numvnodes--; 2461 mtx_unlock(&vnode_free_list_mtx); 2462 bo = &vp->v_bufobj; 2463 VNASSERT((vp->v_iflag & VI_FREE) == 0, vp, 2464 ("cleaned vnode still on the free list.")); 2465 VNASSERT(vp->v_data == NULL, vp, ("cleaned vnode isn't")); 2466 VNASSERT(vp->v_holdcnt == 0, vp, ("Non-zero hold count")); 2467 VNASSERT(vp->v_usecount == 0, vp, ("Non-zero use count")); 2468 VNASSERT(vp->v_writecount == 0, vp, ("Non-zero write count")); 2469 VNASSERT(bo->bo_numoutput == 0, vp, ("Clean vnode has pending I/O's")); 2470 VNASSERT(bo->bo_clean.bv_cnt == 0, vp, ("cleanbufcnt not 0")); 2471 VNASSERT(bo->bo_clean.bv_root == NULL, vp, ("cleanblkroot not NULL")); 2472 VNASSERT(bo->bo_dirty.bv_cnt == 0, vp, ("dirtybufcnt not 0")); 2473 VNASSERT(bo->bo_dirty.bv_root == NULL, vp, ("dirtyblkroot not NULL")); 2474 VNASSERT(TAILQ_EMPTY(&vp->v_cache_dst), vp, ("vp has namecache dst")); 2475 VNASSERT(LIST_EMPTY(&vp->v_cache_src), vp, ("vp has namecache src")); 2476 VNASSERT(vp->v_cache_dd == NULL, vp, ("vp has namecache for ..")); 2477 VI_UNLOCK(vp); 2478 #ifdef MAC 2479 mac_vnode_destroy(vp); 2480 #endif 2481 if (vp->v_pollinfo != NULL) 2482 destroy_vpollinfo(vp->v_pollinfo); 2483 #ifdef INVARIANTS 2484 /* XXX Elsewhere we detect an already freed vnode via NULL v_op. */ 2485 vp->v_op = NULL; 2486 #endif 2487 rangelock_destroy(&vp->v_rl); 2488 lockdestroy(vp->v_vnlock); 2489 mtx_destroy(&vp->v_interlock); 2490 mtx_destroy(BO_MTX(bo)); 2491 uma_zfree(vnode_zone, vp); 2492 } 2493 2494 /* 2495 * Call VOP_INACTIVE on the vnode and manage the DOINGINACT and OWEINACT 2496 * flags. DOINGINACT prevents us from recursing in calls to vinactive. 2497 * OWEINACT tracks whether a vnode missed a call to inactive due to a 2498 * failed lock upgrade. 2499 */ 2500 void 2501 vinactive(struct vnode *vp, struct thread *td) 2502 { 2503 struct vm_object *obj; 2504 2505 ASSERT_VOP_ELOCKED(vp, "vinactive"); 2506 ASSERT_VI_LOCKED(vp, "vinactive"); 2507 VNASSERT((vp->v_iflag & VI_DOINGINACT) == 0, vp, 2508 ("vinactive: recursed on VI_DOINGINACT")); 2509 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2510 vp->v_iflag |= VI_DOINGINACT; 2511 vp->v_iflag &= ~VI_OWEINACT; 2512 VI_UNLOCK(vp); 2513 /* 2514 * Before moving off the active list, we must be sure that any 2515 * modified pages are on the vnode's dirty list since these will 2516 * no longer be checked once the vnode is on the inactive list. 2517 * Because the vnode vm object keeps a hold reference on the vnode 2518 * if there is at least one resident non-cached page, the vnode 2519 * cannot leave the active list without the page cleanup done. 2520 */ 2521 obj = vp->v_object; 2522 if (obj != NULL && (obj->flags & OBJ_MIGHTBEDIRTY) != 0) { 2523 VM_OBJECT_LOCK(obj); 2524 vm_object_page_clean(obj, 0, 0, OBJPC_NOSYNC); 2525 VM_OBJECT_UNLOCK(obj); 2526 } 2527 VOP_INACTIVE(vp, td); 2528 VI_LOCK(vp); 2529 VNASSERT(vp->v_iflag & VI_DOINGINACT, vp, 2530 ("vinactive: lost VI_DOINGINACT")); 2531 vp->v_iflag &= ~VI_DOINGINACT; 2532 } 2533 2534 /* 2535 * Remove any vnodes in the vnode table belonging to mount point mp. 2536 * 2537 * If FORCECLOSE is not specified, there should not be any active ones, 2538 * return error if any are found (nb: this is a user error, not a 2539 * system error). If FORCECLOSE is specified, detach any active vnodes 2540 * that are found. 2541 * 2542 * If WRITECLOSE is set, only flush out regular file vnodes open for 2543 * writing. 2544 * 2545 * SKIPSYSTEM causes any vnodes marked VV_SYSTEM to be skipped. 2546 * 2547 * `rootrefs' specifies the base reference count for the root vnode 2548 * of this filesystem. The root vnode is considered busy if its 2549 * v_usecount exceeds this value. On a successful return, vflush(, td) 2550 * will call vrele() on the root vnode exactly rootrefs times. 2551 * If the SKIPSYSTEM or WRITECLOSE flags are specified, rootrefs must 2552 * be zero. 2553 */ 2554 #ifdef DIAGNOSTIC 2555 static int busyprt = 0; /* print out busy vnodes */ 2556 SYSCTL_INT(_debug, OID_AUTO, busyprt, CTLFLAG_RW, &busyprt, 0, "Print out busy vnodes"); 2557 #endif 2558 2559 int 2560 vflush(struct mount *mp, int rootrefs, int flags, struct thread *td) 2561 { 2562 struct vnode *vp, *mvp, *rootvp = NULL; 2563 struct vattr vattr; 2564 int busy = 0, error; 2565 2566 CTR4(KTR_VFS, "%s: mp %p with rootrefs %d and flags %d", __func__, mp, 2567 rootrefs, flags); 2568 if (rootrefs > 0) { 2569 KASSERT((flags & (SKIPSYSTEM | WRITECLOSE)) == 0, 2570 ("vflush: bad args")); 2571 /* 2572 * Get the filesystem root vnode. We can vput() it 2573 * immediately, since with rootrefs > 0, it won't go away. 2574 */ 2575 if ((error = VFS_ROOT(mp, LK_EXCLUSIVE, &rootvp)) != 0) { 2576 CTR2(KTR_VFS, "%s: vfs_root lookup failed with %d", 2577 __func__, error); 2578 return (error); 2579 } 2580 vput(rootvp); 2581 } 2582 loop: 2583 MNT_VNODE_FOREACH_ALL(vp, mp, mvp) { 2584 vholdl(vp); 2585 error = vn_lock(vp, LK_INTERLOCK | LK_EXCLUSIVE); 2586 if (error) { 2587 vdrop(vp); 2588 MNT_VNODE_FOREACH_ALL_ABORT(mp, mvp); 2589 goto loop; 2590 } 2591 /* 2592 * Skip over a vnodes marked VV_SYSTEM. 2593 */ 2594 if ((flags & SKIPSYSTEM) && (vp->v_vflag & VV_SYSTEM)) { 2595 VOP_UNLOCK(vp, 0); 2596 vdrop(vp); 2597 continue; 2598 } 2599 /* 2600 * If WRITECLOSE is set, flush out unlinked but still open 2601 * files (even if open only for reading) and regular file 2602 * vnodes open for writing. 2603 */ 2604 if (flags & WRITECLOSE) { 2605 if (vp->v_object != NULL) { 2606 VM_OBJECT_LOCK(vp->v_object); 2607 vm_object_page_clean(vp->v_object, 0, 0, 0); 2608 VM_OBJECT_UNLOCK(vp->v_object); 2609 } 2610 error = VOP_FSYNC(vp, MNT_WAIT, td); 2611 if (error != 0) { 2612 VOP_UNLOCK(vp, 0); 2613 vdrop(vp); 2614 MNT_VNODE_FOREACH_ALL_ABORT(mp, mvp); 2615 return (error); 2616 } 2617 error = VOP_GETATTR(vp, &vattr, td->td_ucred); 2618 VI_LOCK(vp); 2619 2620 if ((vp->v_type == VNON || 2621 (error == 0 && vattr.va_nlink > 0)) && 2622 (vp->v_writecount == 0 || vp->v_type != VREG)) { 2623 VOP_UNLOCK(vp, 0); 2624 vdropl(vp); 2625 continue; 2626 } 2627 } else 2628 VI_LOCK(vp); 2629 /* 2630 * With v_usecount == 0, all we need to do is clear out the 2631 * vnode data structures and we are done. 2632 * 2633 * If FORCECLOSE is set, forcibly close the vnode. 2634 */ 2635 if (vp->v_usecount == 0 || (flags & FORCECLOSE)) { 2636 VNASSERT(vp->v_usecount == 0 || 2637 (vp->v_type != VCHR && vp->v_type != VBLK), vp, 2638 ("device VNODE %p is FORCECLOSED", vp)); 2639 vgonel(vp); 2640 } else { 2641 busy++; 2642 #ifdef DIAGNOSTIC 2643 if (busyprt) 2644 vprint("vflush: busy vnode", vp); 2645 #endif 2646 } 2647 VOP_UNLOCK(vp, 0); 2648 vdropl(vp); 2649 } 2650 if (rootrefs > 0 && (flags & FORCECLOSE) == 0) { 2651 /* 2652 * If just the root vnode is busy, and if its refcount 2653 * is equal to `rootrefs', then go ahead and kill it. 2654 */ 2655 VI_LOCK(rootvp); 2656 KASSERT(busy > 0, ("vflush: not busy")); 2657 VNASSERT(rootvp->v_usecount >= rootrefs, rootvp, 2658 ("vflush: usecount %d < rootrefs %d", 2659 rootvp->v_usecount, rootrefs)); 2660 if (busy == 1 && rootvp->v_usecount == rootrefs) { 2661 VOP_LOCK(rootvp, LK_EXCLUSIVE|LK_INTERLOCK); 2662 vgone(rootvp); 2663 VOP_UNLOCK(rootvp, 0); 2664 busy = 0; 2665 } else 2666 VI_UNLOCK(rootvp); 2667 } 2668 if (busy) { 2669 CTR2(KTR_VFS, "%s: failing as %d vnodes are busy", __func__, 2670 busy); 2671 return (EBUSY); 2672 } 2673 for (; rootrefs > 0; rootrefs--) 2674 vrele(rootvp); 2675 return (0); 2676 } 2677 2678 /* 2679 * Recycle an unused vnode to the front of the free list. 2680 */ 2681 int 2682 vrecycle(struct vnode *vp) 2683 { 2684 int recycled; 2685 2686 ASSERT_VOP_ELOCKED(vp, "vrecycle"); 2687 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2688 recycled = 0; 2689 VI_LOCK(vp); 2690 if (vp->v_usecount == 0) { 2691 recycled = 1; 2692 vgonel(vp); 2693 } 2694 VI_UNLOCK(vp); 2695 return (recycled); 2696 } 2697 2698 /* 2699 * Eliminate all activity associated with a vnode 2700 * in preparation for reuse. 2701 */ 2702 void 2703 vgone(struct vnode *vp) 2704 { 2705 VI_LOCK(vp); 2706 vgonel(vp); 2707 VI_UNLOCK(vp); 2708 } 2709 2710 static void 2711 vgonel_reclaim_lowervp_vfs(struct mount *mp __unused, 2712 struct vnode *lowervp __unused) 2713 { 2714 } 2715 2716 /* 2717 * Notify upper mounts about reclaimed vnode. 2718 */ 2719 static void 2720 vgonel_reclaim_lowervp(struct vnode *vp) 2721 { 2722 static struct vfsops vgonel_vfsops = { 2723 .vfs_reclaim_lowervp = vgonel_reclaim_lowervp_vfs 2724 }; 2725 struct mount *mp, *ump, *mmp; 2726 2727 mp = vp->v_mount; 2728 if (mp == NULL) 2729 return; 2730 2731 MNT_ILOCK(mp); 2732 if (TAILQ_EMPTY(&mp->mnt_uppers)) 2733 goto unlock; 2734 MNT_IUNLOCK(mp); 2735 mmp = malloc(sizeof(struct mount), M_TEMP, M_WAITOK | M_ZERO); 2736 mmp->mnt_op = &vgonel_vfsops; 2737 mmp->mnt_kern_flag |= MNTK_MARKER; 2738 MNT_ILOCK(mp); 2739 mp->mnt_kern_flag |= MNTK_VGONE_UPPER; 2740 for (ump = TAILQ_FIRST(&mp->mnt_uppers); ump != NULL;) { 2741 if ((ump->mnt_kern_flag & MNTK_MARKER) != 0) { 2742 ump = TAILQ_NEXT(ump, mnt_upper_link); 2743 continue; 2744 } 2745 TAILQ_INSERT_AFTER(&mp->mnt_uppers, ump, mmp, mnt_upper_link); 2746 MNT_IUNLOCK(mp); 2747 VFS_RECLAIM_LOWERVP(ump, vp); 2748 MNT_ILOCK(mp); 2749 ump = TAILQ_NEXT(mmp, mnt_upper_link); 2750 TAILQ_REMOVE(&mp->mnt_uppers, mmp, mnt_upper_link); 2751 } 2752 free(mmp, M_TEMP); 2753 mp->mnt_kern_flag &= ~MNTK_VGONE_UPPER; 2754 if ((mp->mnt_kern_flag & MNTK_VGONE_WAITER) != 0) { 2755 mp->mnt_kern_flag &= ~MNTK_VGONE_WAITER; 2756 wakeup(&mp->mnt_uppers); 2757 } 2758 unlock: 2759 MNT_IUNLOCK(mp); 2760 } 2761 2762 /* 2763 * vgone, with the vp interlock held. 2764 */ 2765 void 2766 vgonel(struct vnode *vp) 2767 { 2768 struct thread *td; 2769 int oweinact; 2770 int active; 2771 struct mount *mp; 2772 2773 ASSERT_VOP_ELOCKED(vp, "vgonel"); 2774 ASSERT_VI_LOCKED(vp, "vgonel"); 2775 VNASSERT(vp->v_holdcnt, vp, 2776 ("vgonel: vp %p has no reference.", vp)); 2777 CTR2(KTR_VFS, "%s: vp %p", __func__, vp); 2778 td = curthread; 2779 2780 /* 2781 * Don't vgonel if we're already doomed. 2782 */ 2783 if (vp->v_iflag & VI_DOOMED) 2784 return; 2785 vp->v_iflag |= VI_DOOMED; 2786 2787 /* 2788 * Check to see if the vnode is in use. If so, we have to call 2789 * VOP_CLOSE() and VOP_INACTIVE(). 2790 */ 2791 active = vp->v_usecount; 2792 oweinact = (vp->v_iflag & VI_OWEINACT); 2793 VI_UNLOCK(vp); 2794 vgonel_reclaim_lowervp(vp); 2795 2796 /* 2797 * Clean out any buffers associated with the vnode. 2798 * If the flush fails, just toss the buffers. 2799 */ 2800 mp = NULL; 2801 if (!TAILQ_EMPTY(&vp->v_bufobj.bo_dirty.bv_hd)) 2802 (void) vn_start_secondary_write(vp, &mp, V_WAIT); 2803 if (vinvalbuf(vp, V_SAVE, 0, 0) != 0) 2804 vinvalbuf(vp, 0, 0, 0); 2805 2806 /* 2807 * If purging an active vnode, it must be closed and 2808 * deactivated before being reclaimed. 2809 */ 2810 if (active) 2811 VOP_CLOSE(vp, FNONBLOCK, NOCRED, td); 2812 if (oweinact || active) { 2813 VI_LOCK(vp); 2814 if ((vp->v_iflag & VI_DOINGINACT) == 0) 2815 vinactive(vp, td); 2816 VI_UNLOCK(vp); 2817 } 2818 if (vp->v_type == VSOCK) 2819 vfs_unp_reclaim(vp); 2820 /* 2821 * Reclaim the vnode. 2822 */ 2823 if (VOP_RECLAIM(vp, td)) 2824 panic("vgone: cannot reclaim"); 2825 if (mp != NULL) 2826 vn_finished_secondary_write(mp); 2827 VNASSERT(vp->v_object == NULL, vp, 2828 ("vop_reclaim left v_object vp=%p, tag=%s", vp, vp->v_tag)); 2829 /* 2830 * Clear the advisory locks and wake up waiting threads. 2831 */ 2832 (void)VOP_ADVLOCKPURGE(vp); 2833 /* 2834 * Delete from old mount point vnode list. 2835 */ 2836 delmntque(vp); 2837 cache_purge(vp); 2838 /* 2839 * Done with purge, reset to the standard lock and invalidate 2840 * the vnode. 2841 */ 2842 VI_LOCK(vp); 2843 vp->v_vnlock = &vp->v_lock; 2844 vp->v_op = &dead_vnodeops; 2845 vp->v_tag = "none"; 2846 vp->v_type = VBAD; 2847 } 2848 2849 /* 2850 * Calculate the total number of references to a special device. 2851 */ 2852 int 2853 vcount(struct vnode *vp) 2854 { 2855 int count; 2856 2857 dev_lock(); 2858 count = vp->v_rdev->si_usecount; 2859 dev_unlock(); 2860 return (count); 2861 } 2862 2863 /* 2864 * Same as above, but using the struct cdev *as argument 2865 */ 2866 int 2867 count_dev(struct cdev *dev) 2868 { 2869 int count; 2870 2871 dev_lock(); 2872 count = dev->si_usecount; 2873 dev_unlock(); 2874 return(count); 2875 } 2876 2877 /* 2878 * Print out a description of a vnode. 2879 */ 2880 static char *typename[] = 2881 {"VNON", "VREG", "VDIR", "VBLK", "VCHR", "VLNK", "VSOCK", "VFIFO", "VBAD", 2882 "VMARKER"}; 2883 2884 void 2885 vn_printf(struct vnode *vp, const char *fmt, ...) 2886 { 2887 va_list ap; 2888 char buf[256], buf2[16]; 2889 u_long flags; 2890 2891 va_start(ap, fmt); 2892 vprintf(fmt, ap); 2893 va_end(ap); 2894 printf("%p: ", (void *)vp); 2895 printf("tag %s, type %s\n", vp->v_tag, typename[vp->v_type]); 2896 printf(" usecount %d, writecount %d, refcount %d mountedhere %p\n", 2897 vp->v_usecount, vp->v_writecount, vp->v_holdcnt, vp->v_mountedhere); 2898 buf[0] = '\0'; 2899 buf[1] = '\0'; 2900 if (vp->v_vflag & VV_ROOT) 2901 strlcat(buf, "|VV_ROOT", sizeof(buf)); 2902 if (vp->v_vflag & VV_ISTTY) 2903 strlcat(buf, "|VV_ISTTY", sizeof(buf)); 2904 if (vp->v_vflag & VV_NOSYNC) 2905 strlcat(buf, "|VV_NOSYNC", sizeof(buf)); 2906 if (vp->v_vflag & VV_ETERNALDEV) 2907 strlcat(buf, "|VV_ETERNALDEV", sizeof(buf)); 2908 if (vp->v_vflag & VV_CACHEDLABEL) 2909 strlcat(buf, "|VV_CACHEDLABEL", sizeof(buf)); 2910 if (vp->v_vflag & VV_TEXT) 2911 strlcat(buf, "|VV_TEXT", sizeof(buf)); 2912 if (vp->v_vflag & VV_COPYONWRITE) 2913 strlcat(buf, "|VV_COPYONWRITE", sizeof(buf)); 2914 if (vp->v_vflag & VV_SYSTEM) 2915 strlcat(buf, "|VV_SYSTEM", sizeof(buf)); 2916 if (vp->v_vflag & VV_PROCDEP) 2917 strlcat(buf, "|VV_PROCDEP", sizeof(buf)); 2918 if (vp->v_vflag & VV_NOKNOTE) 2919 strlcat(buf, "|VV_NOKNOTE", sizeof(buf)); 2920 if (vp->v_vflag & VV_DELETED) 2921 strlcat(buf, "|VV_DELETED", sizeof(buf)); 2922 if (vp->v_vflag & VV_MD) 2923 strlcat(buf, "|VV_MD", sizeof(buf)); 2924 if (vp->v_vflag & VV_FORCEINSMQ) 2925 strlcat(buf, "|VV_FORCEINSMQ", sizeof(buf)); 2926 flags = vp->v_vflag & ~(VV_ROOT | VV_ISTTY | VV_NOSYNC | VV_ETERNALDEV | 2927 VV_CACHEDLABEL | VV_TEXT | VV_COPYONWRITE | VV_SYSTEM | VV_PROCDEP | 2928 VV_NOKNOTE | VV_DELETED | VV_MD | VV_FORCEINSMQ); 2929 if (flags != 0) { 2930 snprintf(buf2, sizeof(buf2), "|VV(0x%lx)", flags); 2931 strlcat(buf, buf2, sizeof(buf)); 2932 } 2933 if (vp->v_iflag & VI_MOUNT) 2934 strlcat(buf, "|VI_MOUNT", sizeof(buf)); 2935 if (vp->v_iflag & VI_AGE) 2936 strlcat(buf, "|VI_AGE", sizeof(buf)); 2937 if (vp->v_iflag & VI_DOOMED) 2938 strlcat(buf, "|VI_DOOMED", sizeof(buf)); 2939 if (vp->v_iflag & VI_FREE) 2940 strlcat(buf, "|VI_FREE", sizeof(buf)); 2941 if (vp->v_iflag & VI_ACTIVE) 2942 strlcat(buf, "|VI_ACTIVE", sizeof(buf)); 2943 if (vp->v_iflag & VI_DOINGINACT) 2944 strlcat(buf, "|VI_DOINGINACT", sizeof(buf)); 2945 if (vp->v_iflag & VI_OWEINACT) 2946 strlcat(buf, "|VI_OWEINACT", sizeof(buf)); 2947 flags = vp->v_iflag & ~(VI_MOUNT | VI_AGE | VI_DOOMED | VI_FREE | 2948 VI_ACTIVE | VI_DOINGINACT | VI_OWEINACT); 2949 if (flags != 0) { 2950 snprintf(buf2, sizeof(buf2), "|VI(0x%lx)", flags); 2951 strlcat(buf, buf2, sizeof(buf)); 2952 } 2953 printf(" flags (%s)\n", buf + 1); 2954 if (mtx_owned(VI_MTX(vp))) 2955 printf(" VI_LOCKed"); 2956 if (vp->v_object != NULL) 2957 printf(" v_object %p ref %d pages %d\n", 2958 vp->v_object, vp->v_object->ref_count, 2959 vp->v_object->resident_page_count); 2960 printf(" "); 2961 lockmgr_printinfo(vp->v_vnlock); 2962 if (vp->v_data != NULL) 2963 VOP_PRINT(vp); 2964 } 2965 2966 #ifdef DDB 2967 /* 2968 * List all of the locked vnodes in the system. 2969 * Called when debugging the kernel. 2970 */ 2971 DB_SHOW_COMMAND(lockedvnods, lockedvnodes) 2972 { 2973 struct mount *mp, *nmp; 2974 struct vnode *vp; 2975 2976 /* 2977 * Note: because this is DDB, we can't obey the locking semantics 2978 * for these structures, which means we could catch an inconsistent 2979 * state and dereference a nasty pointer. Not much to be done 2980 * about that. 2981 */ 2982 db_printf("Locked vnodes\n"); 2983 for (mp = TAILQ_FIRST(&mountlist); mp != NULL; mp = nmp) { 2984 nmp = TAILQ_NEXT(mp, mnt_list); 2985 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) { 2986 if (vp->v_type != VMARKER && 2987 VOP_ISLOCKED(vp)) 2988 vprint("", vp); 2989 } 2990 nmp = TAILQ_NEXT(mp, mnt_list); 2991 } 2992 } 2993 2994 /* 2995 * Show details about the given vnode. 2996 */ 2997 DB_SHOW_COMMAND(vnode, db_show_vnode) 2998 { 2999 struct vnode *vp; 3000 3001 if (!have_addr) 3002 return; 3003 vp = (struct vnode *)addr; 3004 vn_printf(vp, "vnode "); 3005 } 3006 3007 /* 3008 * Show details about the given mount point. 3009 */ 3010 DB_SHOW_COMMAND(mount, db_show_mount) 3011 { 3012 struct mount *mp; 3013 struct vfsopt *opt; 3014 struct statfs *sp; 3015 struct vnode *vp; 3016 char buf[512]; 3017 uint64_t mflags; 3018 u_int flags; 3019 3020 if (!have_addr) { 3021 /* No address given, print short info about all mount points. */ 3022 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 3023 db_printf("%p %s on %s (%s)\n", mp, 3024 mp->mnt_stat.f_mntfromname, 3025 mp->mnt_stat.f_mntonname, 3026 mp->mnt_stat.f_fstypename); 3027 if (db_pager_quit) 3028 break; 3029 } 3030 db_printf("\nMore info: show mount <addr>\n"); 3031 return; 3032 } 3033 3034 mp = (struct mount *)addr; 3035 db_printf("%p %s on %s (%s)\n", mp, mp->mnt_stat.f_mntfromname, 3036 mp->mnt_stat.f_mntonname, mp->mnt_stat.f_fstypename); 3037 3038 buf[0] = '\0'; 3039 mflags = mp->mnt_flag; 3040 #define MNT_FLAG(flag) do { \ 3041 if (mflags & (flag)) { \ 3042 if (buf[0] != '\0') \ 3043 strlcat(buf, ", ", sizeof(buf)); \ 3044 strlcat(buf, (#flag) + 4, sizeof(buf)); \ 3045 mflags &= ~(flag); \ 3046 } \ 3047 } while (0) 3048 MNT_FLAG(MNT_RDONLY); 3049 MNT_FLAG(MNT_SYNCHRONOUS); 3050 MNT_FLAG(MNT_NOEXEC); 3051 MNT_FLAG(MNT_NOSUID); 3052 MNT_FLAG(MNT_NFS4ACLS); 3053 MNT_FLAG(MNT_UNION); 3054 MNT_FLAG(MNT_ASYNC); 3055 MNT_FLAG(MNT_SUIDDIR); 3056 MNT_FLAG(MNT_SOFTDEP); 3057 MNT_FLAG(MNT_NOSYMFOLLOW); 3058 MNT_FLAG(MNT_GJOURNAL); 3059 MNT_FLAG(MNT_MULTILABEL); 3060 MNT_FLAG(MNT_ACLS); 3061 MNT_FLAG(MNT_NOATIME); 3062 MNT_FLAG(MNT_NOCLUSTERR); 3063 MNT_FLAG(MNT_NOCLUSTERW); 3064 MNT_FLAG(MNT_SUJ); 3065 MNT_FLAG(MNT_EXRDONLY); 3066 MNT_FLAG(MNT_EXPORTED); 3067 MNT_FLAG(MNT_DEFEXPORTED); 3068 MNT_FLAG(MNT_EXPORTANON); 3069 MNT_FLAG(MNT_EXKERB); 3070 MNT_FLAG(MNT_EXPUBLIC); 3071 MNT_FLAG(MNT_LOCAL); 3072 MNT_FLAG(MNT_QUOTA); 3073 MNT_FLAG(MNT_ROOTFS); 3074 MNT_FLAG(MNT_USER); 3075 MNT_FLAG(MNT_IGNORE); 3076 MNT_FLAG(MNT_UPDATE); 3077 MNT_FLAG(MNT_DELEXPORT); 3078 MNT_FLAG(MNT_RELOAD); 3079 MNT_FLAG(MNT_FORCE); 3080 MNT_FLAG(MNT_SNAPSHOT); 3081 MNT_FLAG(MNT_BYFSID); 3082 #undef MNT_FLAG 3083 if (mflags != 0) { 3084 if (buf[0] != '\0') 3085 strlcat(buf, ", ", sizeof(buf)); 3086 snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf), 3087 "0x%016jx", mflags); 3088 } 3089 db_printf(" mnt_flag = %s\n", buf); 3090 3091 buf[0] = '\0'; 3092 flags = mp->mnt_kern_flag; 3093 #define MNT_KERN_FLAG(flag) do { \ 3094 if (flags & (flag)) { \ 3095 if (buf[0] != '\0') \ 3096 strlcat(buf, ", ", sizeof(buf)); \ 3097 strlcat(buf, (#flag) + 5, sizeof(buf)); \ 3098 flags &= ~(flag); \ 3099 } \ 3100 } while (0) 3101 MNT_KERN_FLAG(MNTK_UNMOUNTF); 3102 MNT_KERN_FLAG(MNTK_ASYNC); 3103 MNT_KERN_FLAG(MNTK_SOFTDEP); 3104 MNT_KERN_FLAG(MNTK_NOINSMNTQ); 3105 MNT_KERN_FLAG(MNTK_DRAINING); 3106 MNT_KERN_FLAG(MNTK_REFEXPIRE); 3107 MNT_KERN_FLAG(MNTK_EXTENDED_SHARED); 3108 MNT_KERN_FLAG(MNTK_SHARED_WRITES); 3109 MNT_KERN_FLAG(MNTK_NO_IOPF); 3110 MNT_KERN_FLAG(MNTK_VGONE_UPPER); 3111 MNT_KERN_FLAG(MNTK_VGONE_WAITER); 3112 MNT_KERN_FLAG(MNTK_LOOKUP_EXCL_DOTDOT); 3113 MNT_KERN_FLAG(MNTK_MARKER); 3114 MNT_KERN_FLAG(MNTK_NOASYNC); 3115 MNT_KERN_FLAG(MNTK_UNMOUNT); 3116 MNT_KERN_FLAG(MNTK_MWAIT); 3117 MNT_KERN_FLAG(MNTK_SUSPEND); 3118 MNT_KERN_FLAG(MNTK_SUSPEND2); 3119 MNT_KERN_FLAG(MNTK_SUSPENDED); 3120 MNT_KERN_FLAG(MNTK_LOOKUP_SHARED); 3121 MNT_KERN_FLAG(MNTK_NOKNOTE); 3122 #undef MNT_KERN_FLAG 3123 if (flags != 0) { 3124 if (buf[0] != '\0') 3125 strlcat(buf, ", ", sizeof(buf)); 3126 snprintf(buf + strlen(buf), sizeof(buf) - strlen(buf), 3127 "0x%08x", flags); 3128 } 3129 db_printf(" mnt_kern_flag = %s\n", buf); 3130 3131 db_printf(" mnt_opt = "); 3132 opt = TAILQ_FIRST(mp->mnt_opt); 3133 if (opt != NULL) { 3134 db_printf("%s", opt->name); 3135 opt = TAILQ_NEXT(opt, link); 3136 while (opt != NULL) { 3137 db_printf(", %s", opt->name); 3138 opt = TAILQ_NEXT(opt, link); 3139 } 3140 } 3141 db_printf("\n"); 3142 3143 sp = &mp->mnt_stat; 3144 db_printf(" mnt_stat = { version=%u type=%u flags=0x%016jx " 3145 "bsize=%ju iosize=%ju blocks=%ju bfree=%ju bavail=%jd files=%ju " 3146 "ffree=%jd syncwrites=%ju asyncwrites=%ju syncreads=%ju " 3147 "asyncreads=%ju namemax=%u owner=%u fsid=[%d, %d] }\n", 3148 (u_int)sp->f_version, (u_int)sp->f_type, (uintmax_t)sp->f_flags, 3149 (uintmax_t)sp->f_bsize, (uintmax_t)sp->f_iosize, 3150 (uintmax_t)sp->f_blocks, (uintmax_t)sp->f_bfree, 3151 (intmax_t)sp->f_bavail, (uintmax_t)sp->f_files, 3152 (intmax_t)sp->f_ffree, (uintmax_t)sp->f_syncwrites, 3153 (uintmax_t)sp->f_asyncwrites, (uintmax_t)sp->f_syncreads, 3154 (uintmax_t)sp->f_asyncreads, (u_int)sp->f_namemax, 3155 (u_int)sp->f_owner, (int)sp->f_fsid.val[0], (int)sp->f_fsid.val[1]); 3156 3157 db_printf(" mnt_cred = { uid=%u ruid=%u", 3158 (u_int)mp->mnt_cred->cr_uid, (u_int)mp->mnt_cred->cr_ruid); 3159 if (jailed(mp->mnt_cred)) 3160 db_printf(", jail=%d", mp->mnt_cred->cr_prison->pr_id); 3161 db_printf(" }\n"); 3162 db_printf(" mnt_ref = %d\n", mp->mnt_ref); 3163 db_printf(" mnt_gen = %d\n", mp->mnt_gen); 3164 db_printf(" mnt_nvnodelistsize = %d\n", mp->mnt_nvnodelistsize); 3165 db_printf(" mnt_activevnodelistsize = %d\n", 3166 mp->mnt_activevnodelistsize); 3167 db_printf(" mnt_writeopcount = %d\n", mp->mnt_writeopcount); 3168 db_printf(" mnt_maxsymlinklen = %d\n", mp->mnt_maxsymlinklen); 3169 db_printf(" mnt_iosize_max = %d\n", mp->mnt_iosize_max); 3170 db_printf(" mnt_hashseed = %u\n", mp->mnt_hashseed); 3171 db_printf(" mnt_secondary_writes = %d\n", mp->mnt_secondary_writes); 3172 db_printf(" mnt_secondary_accwrites = %d\n", 3173 mp->mnt_secondary_accwrites); 3174 db_printf(" mnt_gjprovider = %s\n", 3175 mp->mnt_gjprovider != NULL ? mp->mnt_gjprovider : "NULL"); 3176 3177 db_printf("\n\nList of active vnodes\n"); 3178 TAILQ_FOREACH(vp, &mp->mnt_activevnodelist, v_actfreelist) { 3179 if (vp->v_type != VMARKER) { 3180 vn_printf(vp, "vnode "); 3181 if (db_pager_quit) 3182 break; 3183 } 3184 } 3185 db_printf("\n\nList of inactive vnodes\n"); 3186 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) { 3187 if (vp->v_type != VMARKER && (vp->v_iflag & VI_ACTIVE) == 0) { 3188 vn_printf(vp, "vnode "); 3189 if (db_pager_quit) 3190 break; 3191 } 3192 } 3193 } 3194 #endif /* DDB */ 3195 3196 /* 3197 * Fill in a struct xvfsconf based on a struct vfsconf. 3198 */ 3199 static int 3200 vfsconf2x(struct sysctl_req *req, struct vfsconf *vfsp) 3201 { 3202 struct xvfsconf xvfsp; 3203 3204 bzero(&xvfsp, sizeof(xvfsp)); 3205 strcpy(xvfsp.vfc_name, vfsp->vfc_name); 3206 xvfsp.vfc_typenum = vfsp->vfc_typenum; 3207 xvfsp.vfc_refcount = vfsp->vfc_refcount; 3208 xvfsp.vfc_flags = vfsp->vfc_flags; 3209 /* 3210 * These are unused in userland, we keep them 3211 * to not break binary compatibility. 3212 */ 3213 xvfsp.vfc_vfsops = NULL; 3214 xvfsp.vfc_next = NULL; 3215 return (SYSCTL_OUT(req, &xvfsp, sizeof(xvfsp))); 3216 } 3217 3218 #ifdef COMPAT_FREEBSD32 3219 struct xvfsconf32 { 3220 uint32_t vfc_vfsops; 3221 char vfc_name[MFSNAMELEN]; 3222 int32_t vfc_typenum; 3223 int32_t vfc_refcount; 3224 int32_t vfc_flags; 3225 uint32_t vfc_next; 3226 }; 3227 3228 static int 3229 vfsconf2x32(struct sysctl_req *req, struct vfsconf *vfsp) 3230 { 3231 struct xvfsconf32 xvfsp; 3232 3233 strcpy(xvfsp.vfc_name, vfsp->vfc_name); 3234 xvfsp.vfc_typenum = vfsp->vfc_typenum; 3235 xvfsp.vfc_refcount = vfsp->vfc_refcount; 3236 xvfsp.vfc_flags = vfsp->vfc_flags; 3237 xvfsp.vfc_vfsops = 0; 3238 xvfsp.vfc_next = 0; 3239 return (SYSCTL_OUT(req, &xvfsp, sizeof(xvfsp))); 3240 } 3241 #endif 3242 3243 /* 3244 * Top level filesystem related information gathering. 3245 */ 3246 static int 3247 sysctl_vfs_conflist(SYSCTL_HANDLER_ARGS) 3248 { 3249 struct vfsconf *vfsp; 3250 int error; 3251 3252 error = 0; 3253 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) { 3254 #ifdef COMPAT_FREEBSD32 3255 if (req->flags & SCTL_MASK32) 3256 error = vfsconf2x32(req, vfsp); 3257 else 3258 #endif 3259 error = vfsconf2x(req, vfsp); 3260 if (error) 3261 break; 3262 } 3263 return (error); 3264 } 3265 3266 SYSCTL_PROC(_vfs, OID_AUTO, conflist, CTLTYPE_OPAQUE | CTLFLAG_RD, 3267 NULL, 0, sysctl_vfs_conflist, 3268 "S,xvfsconf", "List of all configured filesystems"); 3269 3270 #ifndef BURN_BRIDGES 3271 static int sysctl_ovfs_conf(SYSCTL_HANDLER_ARGS); 3272 3273 static int 3274 vfs_sysctl(SYSCTL_HANDLER_ARGS) 3275 { 3276 int *name = (int *)arg1 - 1; /* XXX */ 3277 u_int namelen = arg2 + 1; /* XXX */ 3278 struct vfsconf *vfsp; 3279 3280 log(LOG_WARNING, "userland calling deprecated sysctl, " 3281 "please rebuild world\n"); 3282 3283 #if 1 || defined(COMPAT_PRELITE2) 3284 /* Resolve ambiguity between VFS_VFSCONF and VFS_GENERIC. */ 3285 if (namelen == 1) 3286 return (sysctl_ovfs_conf(oidp, arg1, arg2, req)); 3287 #endif 3288 3289 switch (name[1]) { 3290 case VFS_MAXTYPENUM: 3291 if (namelen != 2) 3292 return (ENOTDIR); 3293 return (SYSCTL_OUT(req, &maxvfsconf, sizeof(int))); 3294 case VFS_CONF: 3295 if (namelen != 3) 3296 return (ENOTDIR); /* overloaded */ 3297 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) 3298 if (vfsp->vfc_typenum == name[2]) 3299 break; 3300 if (vfsp == NULL) 3301 return (EOPNOTSUPP); 3302 #ifdef COMPAT_FREEBSD32 3303 if (req->flags & SCTL_MASK32) 3304 return (vfsconf2x32(req, vfsp)); 3305 else 3306 #endif 3307 return (vfsconf2x(req, vfsp)); 3308 } 3309 return (EOPNOTSUPP); 3310 } 3311 3312 static SYSCTL_NODE(_vfs, VFS_GENERIC, generic, CTLFLAG_RD | CTLFLAG_SKIP, 3313 vfs_sysctl, "Generic filesystem"); 3314 3315 #if 1 || defined(COMPAT_PRELITE2) 3316 3317 static int 3318 sysctl_ovfs_conf(SYSCTL_HANDLER_ARGS) 3319 { 3320 int error; 3321 struct vfsconf *vfsp; 3322 struct ovfsconf ovfs; 3323 3324 TAILQ_FOREACH(vfsp, &vfsconf, vfc_list) { 3325 bzero(&ovfs, sizeof(ovfs)); 3326 ovfs.vfc_vfsops = vfsp->vfc_vfsops; /* XXX used as flag */ 3327 strcpy(ovfs.vfc_name, vfsp->vfc_name); 3328 ovfs.vfc_index = vfsp->vfc_typenum; 3329 ovfs.vfc_refcount = vfsp->vfc_refcount; 3330 ovfs.vfc_flags = vfsp->vfc_flags; 3331 error = SYSCTL_OUT(req, &ovfs, sizeof ovfs); 3332 if (error) 3333 return error; 3334 } 3335 return 0; 3336 } 3337 3338 #endif /* 1 || COMPAT_PRELITE2 */ 3339 #endif /* !BURN_BRIDGES */ 3340 3341 #define KINFO_VNODESLOP 10 3342 #ifdef notyet 3343 /* 3344 * Dump vnode list (via sysctl). 3345 */ 3346 /* ARGSUSED */ 3347 static int 3348 sysctl_vnode(SYSCTL_HANDLER_ARGS) 3349 { 3350 struct xvnode *xvn; 3351 struct mount *mp; 3352 struct vnode *vp; 3353 int error, len, n; 3354 3355 /* 3356 * Stale numvnodes access is not fatal here. 3357 */ 3358 req->lock = 0; 3359 len = (numvnodes + KINFO_VNODESLOP) * sizeof *xvn; 3360 if (!req->oldptr) 3361 /* Make an estimate */ 3362 return (SYSCTL_OUT(req, 0, len)); 3363 3364 error = sysctl_wire_old_buffer(req, 0); 3365 if (error != 0) 3366 return (error); 3367 xvn = malloc(len, M_TEMP, M_ZERO | M_WAITOK); 3368 n = 0; 3369 mtx_lock(&mountlist_mtx); 3370 TAILQ_FOREACH(mp, &mountlist, mnt_list) { 3371 if (vfs_busy(mp, MBF_NOWAIT | MBF_MNTLSTLOCK)) 3372 continue; 3373 MNT_ILOCK(mp); 3374 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) { 3375 if (n == len) 3376 break; 3377 vref(vp); 3378 xvn[n].xv_size = sizeof *xvn; 3379 xvn[n].xv_vnode = vp; 3380 xvn[n].xv_id = 0; /* XXX compat */ 3381 #define XV_COPY(field) xvn[n].xv_##field = vp->v_##field 3382 XV_COPY(usecount); 3383 XV_COPY(writecount); 3384 XV_COPY(holdcnt); 3385 XV_COPY(mount); 3386 XV_COPY(numoutput); 3387 XV_COPY(type); 3388 #undef XV_COPY 3389 xvn[n].xv_flag = vp->v_vflag; 3390 3391 switch (vp->v_type) { 3392 case VREG: 3393 case VDIR: 3394 case VLNK: 3395 break; 3396 case VBLK: 3397 case VCHR: 3398 if (vp->v_rdev == NULL) { 3399 vrele(vp); 3400 continue; 3401 } 3402 xvn[n].xv_dev = dev2udev(vp->v_rdev); 3403 break; 3404 case VSOCK: 3405 xvn[n].xv_socket = vp->v_socket; 3406 break; 3407 case VFIFO: 3408 xvn[n].xv_fifo = vp->v_fifoinfo; 3409 break; 3410 case VNON: 3411 case VBAD: 3412 default: 3413 /* shouldn't happen? */ 3414 vrele(vp); 3415 continue; 3416 } 3417 vrele(vp); 3418 ++n; 3419 } 3420 MNT_IUNLOCK(mp); 3421 mtx_lock(&mountlist_mtx); 3422 vfs_unbusy(mp); 3423 if (n == len) 3424 break; 3425 } 3426 mtx_unlock(&mountlist_mtx); 3427 3428 error = SYSCTL_OUT(req, xvn, n * sizeof *xvn); 3429 free(xvn, M_TEMP); 3430 return (error); 3431 } 3432 3433 SYSCTL_PROC(_kern, KERN_VNODE, vnode, CTLTYPE_OPAQUE|CTLFLAG_RD, 3434 0, 0, sysctl_vnode, "S,xvnode", ""); 3435 #endif 3436 3437 /* 3438 * Unmount all filesystems. The list is traversed in reverse order 3439 * of mounting to avoid dependencies. 3440 */ 3441 void 3442 vfs_unmountall(void) 3443 { 3444 struct mount *mp; 3445 struct thread *td; 3446 int error; 3447 3448 CTR1(KTR_VFS, "%s: unmounting all filesystems", __func__); 3449 td = curthread; 3450 3451 /* 3452 * Since this only runs when rebooting, it is not interlocked. 3453 */ 3454 while(!TAILQ_EMPTY(&mountlist)) { 3455 mp = TAILQ_LAST(&mountlist, mntlist); 3456 error = dounmount(mp, MNT_FORCE, td); 3457 if (error) { 3458 TAILQ_REMOVE(&mountlist, mp, mnt_list); 3459 /* 3460 * XXX: Due to the way in which we mount the root 3461 * file system off of devfs, devfs will generate a 3462 * "busy" warning when we try to unmount it before 3463 * the root. Don't print a warning as a result in 3464 * order to avoid false positive errors that may 3465 * cause needless upset. 3466 */ 3467 if (strcmp(mp->mnt_vfc->vfc_name, "devfs") != 0) { 3468 printf("unmount of %s failed (", 3469 mp->mnt_stat.f_mntonname); 3470 if (error == EBUSY) 3471 printf("BUSY)\n"); 3472 else 3473 printf("%d)\n", error); 3474 } 3475 } else { 3476 /* The unmount has removed mp from the mountlist */ 3477 } 3478 } 3479 } 3480 3481 /* 3482 * perform msync on all vnodes under a mount point 3483 * the mount point must be locked. 3484 */ 3485 void 3486 vfs_msync(struct mount *mp, int flags) 3487 { 3488 struct vnode *vp, *mvp; 3489 struct vm_object *obj; 3490 3491 CTR2(KTR_VFS, "%s: mp %p", __func__, mp); 3492 MNT_VNODE_FOREACH_ACTIVE(vp, mp, mvp) { 3493 obj = vp->v_object; 3494 if (obj != NULL && (obj->flags & OBJ_MIGHTBEDIRTY) != 0 && 3495 (flags == MNT_WAIT || VOP_ISLOCKED(vp) == 0)) { 3496 if (!vget(vp, 3497 LK_EXCLUSIVE | LK_RETRY | LK_INTERLOCK, 3498 curthread)) { 3499 if (vp->v_vflag & VV_NOSYNC) { /* unlinked */ 3500 vput(vp); 3501 continue; 3502 } 3503 3504 obj = vp->v_object; 3505 if (obj != NULL) { 3506 VM_OBJECT_LOCK(obj); 3507 vm_object_page_clean(obj, 0, 0, 3508 flags == MNT_WAIT ? 3509 OBJPC_SYNC : OBJPC_NOSYNC); 3510 VM_OBJECT_UNLOCK(obj); 3511 } 3512 vput(vp); 3513 } 3514 } else 3515 VI_UNLOCK(vp); 3516 } 3517 } 3518 3519 static void 3520 destroy_vpollinfo(struct vpollinfo *vi) 3521 { 3522 seldrain(&vi->vpi_selinfo); 3523 knlist_destroy(&vi->vpi_selinfo.si_note); 3524 mtx_destroy(&vi->vpi_lock); 3525 uma_zfree(vnodepoll_zone, vi); 3526 } 3527 3528 /* 3529 * Initalize per-vnode helper structure to hold poll-related state. 3530 */ 3531 void 3532 v_addpollinfo(struct vnode *vp) 3533 { 3534 struct vpollinfo *vi; 3535 3536 if (vp->v_pollinfo != NULL) 3537 return; 3538 vi = uma_zalloc(vnodepoll_zone, M_WAITOK); 3539 mtx_init(&vi->vpi_lock, "vnode pollinfo", NULL, MTX_DEF); 3540 knlist_init(&vi->vpi_selinfo.si_note, vp, vfs_knllock, 3541 vfs_knlunlock, vfs_knl_assert_locked, vfs_knl_assert_unlocked); 3542 VI_LOCK(vp); 3543 if (vp->v_pollinfo != NULL) { 3544 VI_UNLOCK(vp); 3545 destroy_vpollinfo(vi); 3546 return; 3547 } 3548 vp->v_pollinfo = vi; 3549 VI_UNLOCK(vp); 3550 } 3551 3552 /* 3553 * Record a process's interest in events which might happen to 3554 * a vnode. Because poll uses the historic select-style interface 3555 * internally, this routine serves as both the ``check for any 3556 * pending events'' and the ``record my interest in future events'' 3557 * functions. (These are done together, while the lock is held, 3558 * to avoid race conditions.) 3559 */ 3560 int 3561 vn_pollrecord(struct vnode *vp, struct thread *td, int events) 3562 { 3563 3564 v_addpollinfo(vp); 3565 mtx_lock(&vp->v_pollinfo->vpi_lock); 3566 if (vp->v_pollinfo->vpi_revents & events) { 3567 /* 3568 * This leaves events we are not interested 3569 * in available for the other process which 3570 * which presumably had requested them 3571 * (otherwise they would never have been 3572 * recorded). 3573 */ 3574 events &= vp->v_pollinfo->vpi_revents; 3575 vp->v_pollinfo->vpi_revents &= ~events; 3576 3577 mtx_unlock(&vp->v_pollinfo->vpi_lock); 3578 return (events); 3579 } 3580 vp->v_pollinfo->vpi_events |= events; 3581 selrecord(td, &vp->v_pollinfo->vpi_selinfo); 3582 mtx_unlock(&vp->v_pollinfo->vpi_lock); 3583 return (0); 3584 } 3585 3586 /* 3587 * Routine to create and manage a filesystem syncer vnode. 3588 */ 3589 #define sync_close ((int (*)(struct vop_close_args *))nullop) 3590 static int sync_fsync(struct vop_fsync_args *); 3591 static int sync_inactive(struct vop_inactive_args *); 3592 static int sync_reclaim(struct vop_reclaim_args *); 3593 3594 static struct vop_vector sync_vnodeops = { 3595 .vop_bypass = VOP_EOPNOTSUPP, 3596 .vop_close = sync_close, /* close */ 3597 .vop_fsync = sync_fsync, /* fsync */ 3598 .vop_inactive = sync_inactive, /* inactive */ 3599 .vop_reclaim = sync_reclaim, /* reclaim */ 3600 .vop_lock1 = vop_stdlock, /* lock */ 3601 .vop_unlock = vop_stdunlock, /* unlock */ 3602 .vop_islocked = vop_stdislocked, /* islocked */ 3603 }; 3604 3605 /* 3606 * Create a new filesystem syncer vnode for the specified mount point. 3607 */ 3608 void 3609 vfs_allocate_syncvnode(struct mount *mp) 3610 { 3611 struct vnode *vp; 3612 struct bufobj *bo; 3613 static long start, incr, next; 3614 int error; 3615 3616 /* Allocate a new vnode */ 3617 error = getnewvnode("syncer", mp, &sync_vnodeops, &vp); 3618 if (error != 0) 3619 panic("vfs_allocate_syncvnode: getnewvnode() failed"); 3620 vp->v_type = VNON; 3621 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 3622 vp->v_vflag |= VV_FORCEINSMQ; 3623 error = insmntque(vp, mp); 3624 if (error != 0) 3625 panic("vfs_allocate_syncvnode: insmntque() failed"); 3626 vp->v_vflag &= ~VV_FORCEINSMQ; 3627 VOP_UNLOCK(vp, 0); 3628 /* 3629 * Place the vnode onto the syncer worklist. We attempt to 3630 * scatter them about on the list so that they will go off 3631 * at evenly distributed times even if all the filesystems 3632 * are mounted at once. 3633 */ 3634 next += incr; 3635 if (next == 0 || next > syncer_maxdelay) { 3636 start /= 2; 3637 incr /= 2; 3638 if (start == 0) { 3639 start = syncer_maxdelay / 2; 3640 incr = syncer_maxdelay; 3641 } 3642 next = start; 3643 } 3644 bo = &vp->v_bufobj; 3645 BO_LOCK(bo); 3646 vn_syncer_add_to_worklist(bo, syncdelay > 0 ? next % syncdelay : 0); 3647 /* XXX - vn_syncer_add_to_worklist() also grabs and drops sync_mtx. */ 3648 mtx_lock(&sync_mtx); 3649 sync_vnode_count++; 3650 if (mp->mnt_syncer == NULL) { 3651 mp->mnt_syncer = vp; 3652 vp = NULL; 3653 } 3654 mtx_unlock(&sync_mtx); 3655 BO_UNLOCK(bo); 3656 if (vp != NULL) { 3657 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 3658 vgone(vp); 3659 vput(vp); 3660 } 3661 } 3662 3663 void 3664 vfs_deallocate_syncvnode(struct mount *mp) 3665 { 3666 struct vnode *vp; 3667 3668 mtx_lock(&sync_mtx); 3669 vp = mp->mnt_syncer; 3670 if (vp != NULL) 3671 mp->mnt_syncer = NULL; 3672 mtx_unlock(&sync_mtx); 3673 if (vp != NULL) 3674 vrele(vp); 3675 } 3676 3677 /* 3678 * Do a lazy sync of the filesystem. 3679 */ 3680 static int 3681 sync_fsync(struct vop_fsync_args *ap) 3682 { 3683 struct vnode *syncvp = ap->a_vp; 3684 struct mount *mp = syncvp->v_mount; 3685 int error, save; 3686 struct bufobj *bo; 3687 3688 /* 3689 * We only need to do something if this is a lazy evaluation. 3690 */ 3691 if (ap->a_waitfor != MNT_LAZY) 3692 return (0); 3693 3694 /* 3695 * Move ourselves to the back of the sync list. 3696 */ 3697 bo = &syncvp->v_bufobj; 3698 BO_LOCK(bo); 3699 vn_syncer_add_to_worklist(bo, syncdelay); 3700 BO_UNLOCK(bo); 3701 3702 /* 3703 * Walk the list of vnodes pushing all that are dirty and 3704 * not already on the sync list. 3705 */ 3706 mtx_lock(&mountlist_mtx); 3707 if (vfs_busy(mp, MBF_NOWAIT | MBF_MNTLSTLOCK) != 0) { 3708 mtx_unlock(&mountlist_mtx); 3709 return (0); 3710 } 3711 if (vn_start_write(NULL, &mp, V_NOWAIT) != 0) { 3712 vfs_unbusy(mp); 3713 return (0); 3714 } 3715 save = curthread_pflags_set(TDP_SYNCIO); 3716 vfs_msync(mp, MNT_NOWAIT); 3717 error = VFS_SYNC(mp, MNT_LAZY); 3718 curthread_pflags_restore(save); 3719 vn_finished_write(mp); 3720 vfs_unbusy(mp); 3721 return (error); 3722 } 3723 3724 /* 3725 * The syncer vnode is no referenced. 3726 */ 3727 static int 3728 sync_inactive(struct vop_inactive_args *ap) 3729 { 3730 3731 vgone(ap->a_vp); 3732 return (0); 3733 } 3734 3735 /* 3736 * The syncer vnode is no longer needed and is being decommissioned. 3737 * 3738 * Modifications to the worklist must be protected by sync_mtx. 3739 */ 3740 static int 3741 sync_reclaim(struct vop_reclaim_args *ap) 3742 { 3743 struct vnode *vp = ap->a_vp; 3744 struct bufobj *bo; 3745 3746 bo = &vp->v_bufobj; 3747 BO_LOCK(bo); 3748 mtx_lock(&sync_mtx); 3749 if (vp->v_mount->mnt_syncer == vp) 3750 vp->v_mount->mnt_syncer = NULL; 3751 if (bo->bo_flag & BO_ONWORKLST) { 3752 LIST_REMOVE(bo, bo_synclist); 3753 syncer_worklist_len--; 3754 sync_vnode_count--; 3755 bo->bo_flag &= ~BO_ONWORKLST; 3756 } 3757 mtx_unlock(&sync_mtx); 3758 BO_UNLOCK(bo); 3759 3760 return (0); 3761 } 3762 3763 /* 3764 * Check if vnode represents a disk device 3765 */ 3766 int 3767 vn_isdisk(struct vnode *vp, int *errp) 3768 { 3769 int error; 3770 3771 error = 0; 3772 dev_lock(); 3773 if (vp->v_type != VCHR) 3774 error = ENOTBLK; 3775 else if (vp->v_rdev == NULL) 3776 error = ENXIO; 3777 else if (vp->v_rdev->si_devsw == NULL) 3778 error = ENXIO; 3779 else if (!(vp->v_rdev->si_devsw->d_flags & D_DISK)) 3780 error = ENOTBLK; 3781 dev_unlock(); 3782 if (errp != NULL) 3783 *errp = error; 3784 return (error == 0); 3785 } 3786 3787 /* 3788 * Common filesystem object access control check routine. Accepts a 3789 * vnode's type, "mode", uid and gid, requested access mode, credentials, 3790 * and optional call-by-reference privused argument allowing vaccess() 3791 * to indicate to the caller whether privilege was used to satisfy the 3792 * request (obsoleted). Returns 0 on success, or an errno on failure. 3793 */ 3794 int 3795 vaccess(enum vtype type, mode_t file_mode, uid_t file_uid, gid_t file_gid, 3796 accmode_t accmode, struct ucred *cred, int *privused) 3797 { 3798 accmode_t dac_granted; 3799 accmode_t priv_granted; 3800 3801 KASSERT((accmode & ~(VEXEC | VWRITE | VREAD | VADMIN | VAPPEND)) == 0, 3802 ("invalid bit in accmode")); 3803 KASSERT((accmode & VAPPEND) == 0 || (accmode & VWRITE), 3804 ("VAPPEND without VWRITE")); 3805 3806 /* 3807 * Look for a normal, non-privileged way to access the file/directory 3808 * as requested. If it exists, go with that. 3809 */ 3810 3811 if (privused != NULL) 3812 *privused = 0; 3813 3814 dac_granted = 0; 3815 3816 /* Check the owner. */ 3817 if (cred->cr_uid == file_uid) { 3818 dac_granted |= VADMIN; 3819 if (file_mode & S_IXUSR) 3820 dac_granted |= VEXEC; 3821 if (file_mode & S_IRUSR) 3822 dac_granted |= VREAD; 3823 if (file_mode & S_IWUSR) 3824 dac_granted |= (VWRITE | VAPPEND); 3825 3826 if ((accmode & dac_granted) == accmode) 3827 return (0); 3828 3829 goto privcheck; 3830 } 3831 3832 /* Otherwise, check the groups (first match) */ 3833 if (groupmember(file_gid, cred)) { 3834 if (file_mode & S_IXGRP) 3835 dac_granted |= VEXEC; 3836 if (file_mode & S_IRGRP) 3837 dac_granted |= VREAD; 3838 if (file_mode & S_IWGRP) 3839 dac_granted |= (VWRITE | VAPPEND); 3840 3841 if ((accmode & dac_granted) == accmode) 3842 return (0); 3843 3844 goto privcheck; 3845 } 3846 3847 /* Otherwise, check everyone else. */ 3848 if (file_mode & S_IXOTH) 3849 dac_granted |= VEXEC; 3850 if (file_mode & S_IROTH) 3851 dac_granted |= VREAD; 3852 if (file_mode & S_IWOTH) 3853 dac_granted |= (VWRITE | VAPPEND); 3854 if ((accmode & dac_granted) == accmode) 3855 return (0); 3856 3857 privcheck: 3858 /* 3859 * Build a privilege mask to determine if the set of privileges 3860 * satisfies the requirements when combined with the granted mask 3861 * from above. For each privilege, if the privilege is required, 3862 * bitwise or the request type onto the priv_granted mask. 3863 */ 3864 priv_granted = 0; 3865 3866 if (type == VDIR) { 3867 /* 3868 * For directories, use PRIV_VFS_LOOKUP to satisfy VEXEC 3869 * requests, instead of PRIV_VFS_EXEC. 3870 */ 3871 if ((accmode & VEXEC) && ((dac_granted & VEXEC) == 0) && 3872 !priv_check_cred(cred, PRIV_VFS_LOOKUP, 0)) 3873 priv_granted |= VEXEC; 3874 } else { 3875 /* 3876 * Ensure that at least one execute bit is on. Otherwise, 3877 * a privileged user will always succeed, and we don't want 3878 * this to happen unless the file really is executable. 3879 */ 3880 if ((accmode & VEXEC) && ((dac_granted & VEXEC) == 0) && 3881 (file_mode & (S_IXUSR | S_IXGRP | S_IXOTH)) != 0 && 3882 !priv_check_cred(cred, PRIV_VFS_EXEC, 0)) 3883 priv_granted |= VEXEC; 3884 } 3885 3886 if ((accmode & VREAD) && ((dac_granted & VREAD) == 0) && 3887 !priv_check_cred(cred, PRIV_VFS_READ, 0)) 3888 priv_granted |= VREAD; 3889 3890 if ((accmode & VWRITE) && ((dac_granted & VWRITE) == 0) && 3891 !priv_check_cred(cred, PRIV_VFS_WRITE, 0)) 3892 priv_granted |= (VWRITE | VAPPEND); 3893 3894 if ((accmode & VADMIN) && ((dac_granted & VADMIN) == 0) && 3895 !priv_check_cred(cred, PRIV_VFS_ADMIN, 0)) 3896 priv_granted |= VADMIN; 3897 3898 if ((accmode & (priv_granted | dac_granted)) == accmode) { 3899 /* XXX audit: privilege used */ 3900 if (privused != NULL) 3901 *privused = 1; 3902 return (0); 3903 } 3904 3905 return ((accmode & VADMIN) ? EPERM : EACCES); 3906 } 3907 3908 /* 3909 * Credential check based on process requesting service, and per-attribute 3910 * permissions. 3911 */ 3912 int 3913 extattr_check_cred(struct vnode *vp, int attrnamespace, struct ucred *cred, 3914 struct thread *td, accmode_t accmode) 3915 { 3916 3917 /* 3918 * Kernel-invoked always succeeds. 3919 */ 3920 if (cred == NOCRED) 3921 return (0); 3922 3923 /* 3924 * Do not allow privileged processes in jail to directly manipulate 3925 * system attributes. 3926 */ 3927 switch (attrnamespace) { 3928 case EXTATTR_NAMESPACE_SYSTEM: 3929 /* Potentially should be: return (EPERM); */ 3930 return (priv_check_cred(cred, PRIV_VFS_EXTATTR_SYSTEM, 0)); 3931 case EXTATTR_NAMESPACE_USER: 3932 return (VOP_ACCESS(vp, accmode, cred, td)); 3933 default: 3934 return (EPERM); 3935 } 3936 } 3937 3938 #ifdef DEBUG_VFS_LOCKS 3939 /* 3940 * This only exists to supress warnings from unlocked specfs accesses. It is 3941 * no longer ok to have an unlocked VFS. 3942 */ 3943 #define IGNORE_LOCK(vp) (panicstr != NULL || (vp) == NULL || \ 3944 (vp)->v_type == VCHR || (vp)->v_type == VBAD) 3945 3946 int vfs_badlock_ddb = 1; /* Drop into debugger on violation. */ 3947 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_ddb, CTLFLAG_RW, &vfs_badlock_ddb, 0, 3948 "Drop into debugger on lock violation"); 3949 3950 int vfs_badlock_mutex = 1; /* Check for interlock across VOPs. */ 3951 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_mutex, CTLFLAG_RW, &vfs_badlock_mutex, 3952 0, "Check for interlock across VOPs"); 3953 3954 int vfs_badlock_print = 1; /* Print lock violations. */ 3955 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_print, CTLFLAG_RW, &vfs_badlock_print, 3956 0, "Print lock violations"); 3957 3958 #ifdef KDB 3959 int vfs_badlock_backtrace = 1; /* Print backtrace at lock violations. */ 3960 SYSCTL_INT(_debug, OID_AUTO, vfs_badlock_backtrace, CTLFLAG_RW, 3961 &vfs_badlock_backtrace, 0, "Print backtrace at lock violations"); 3962 #endif 3963 3964 static void 3965 vfs_badlock(const char *msg, const char *str, struct vnode *vp) 3966 { 3967 3968 #ifdef KDB 3969 if (vfs_badlock_backtrace) 3970 kdb_backtrace(); 3971 #endif 3972 if (vfs_badlock_print) 3973 printf("%s: %p %s\n", str, (void *)vp, msg); 3974 if (vfs_badlock_ddb) 3975 kdb_enter(KDB_WHY_VFSLOCK, "lock violation"); 3976 } 3977 3978 void 3979 assert_vi_locked(struct vnode *vp, const char *str) 3980 { 3981 3982 if (vfs_badlock_mutex && !mtx_owned(VI_MTX(vp))) 3983 vfs_badlock("interlock is not locked but should be", str, vp); 3984 } 3985 3986 void 3987 assert_vi_unlocked(struct vnode *vp, const char *str) 3988 { 3989 3990 if (vfs_badlock_mutex && mtx_owned(VI_MTX(vp))) 3991 vfs_badlock("interlock is locked but should not be", str, vp); 3992 } 3993 3994 void 3995 assert_vop_locked(struct vnode *vp, const char *str) 3996 { 3997 int locked; 3998 3999 if (!IGNORE_LOCK(vp)) { 4000 locked = VOP_ISLOCKED(vp); 4001 if (locked == 0 || locked == LK_EXCLOTHER) 4002 vfs_badlock("is not locked but should be", str, vp); 4003 } 4004 } 4005 4006 void 4007 assert_vop_unlocked(struct vnode *vp, const char *str) 4008 { 4009 4010 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) == LK_EXCLUSIVE) 4011 vfs_badlock("is locked but should not be", str, vp); 4012 } 4013 4014 void 4015 assert_vop_elocked(struct vnode *vp, const char *str) 4016 { 4017 4018 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) != LK_EXCLUSIVE) 4019 vfs_badlock("is not exclusive locked but should be", str, vp); 4020 } 4021 4022 #if 0 4023 void 4024 assert_vop_elocked_other(struct vnode *vp, const char *str) 4025 { 4026 4027 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) != LK_EXCLOTHER) 4028 vfs_badlock("is not exclusive locked by another thread", 4029 str, vp); 4030 } 4031 4032 void 4033 assert_vop_slocked(struct vnode *vp, const char *str) 4034 { 4035 4036 if (!IGNORE_LOCK(vp) && VOP_ISLOCKED(vp) != LK_SHARED) 4037 vfs_badlock("is not locked shared but should be", str, vp); 4038 } 4039 #endif /* 0 */ 4040 #endif /* DEBUG_VFS_LOCKS */ 4041 4042 void 4043 vop_rename_fail(struct vop_rename_args *ap) 4044 { 4045 4046 if (ap->a_tvp != NULL) 4047 vput(ap->a_tvp); 4048 if (ap->a_tdvp == ap->a_tvp) 4049 vrele(ap->a_tdvp); 4050 else 4051 vput(ap->a_tdvp); 4052 vrele(ap->a_fdvp); 4053 vrele(ap->a_fvp); 4054 } 4055 4056 void 4057 vop_rename_pre(void *ap) 4058 { 4059 struct vop_rename_args *a = ap; 4060 4061 #ifdef DEBUG_VFS_LOCKS 4062 if (a->a_tvp) 4063 ASSERT_VI_UNLOCKED(a->a_tvp, "VOP_RENAME"); 4064 ASSERT_VI_UNLOCKED(a->a_tdvp, "VOP_RENAME"); 4065 ASSERT_VI_UNLOCKED(a->a_fvp, "VOP_RENAME"); 4066 ASSERT_VI_UNLOCKED(a->a_fdvp, "VOP_RENAME"); 4067 4068 /* Check the source (from). */ 4069 if (a->a_tdvp->v_vnlock != a->a_fdvp->v_vnlock && 4070 (a->a_tvp == NULL || a->a_tvp->v_vnlock != a->a_fdvp->v_vnlock)) 4071 ASSERT_VOP_UNLOCKED(a->a_fdvp, "vop_rename: fdvp locked"); 4072 if (a->a_tvp == NULL || a->a_tvp->v_vnlock != a->a_fvp->v_vnlock) 4073 ASSERT_VOP_UNLOCKED(a->a_fvp, "vop_rename: fvp locked"); 4074 4075 /* Check the target. */ 4076 if (a->a_tvp) 4077 ASSERT_VOP_LOCKED(a->a_tvp, "vop_rename: tvp not locked"); 4078 ASSERT_VOP_LOCKED(a->a_tdvp, "vop_rename: tdvp not locked"); 4079 #endif 4080 if (a->a_tdvp != a->a_fdvp) 4081 vhold(a->a_fdvp); 4082 if (a->a_tvp != a->a_fvp) 4083 vhold(a->a_fvp); 4084 vhold(a->a_tdvp); 4085 if (a->a_tvp) 4086 vhold(a->a_tvp); 4087 } 4088 4089 void 4090 vop_strategy_pre(void *ap) 4091 { 4092 #ifdef DEBUG_VFS_LOCKS 4093 struct vop_strategy_args *a; 4094 struct buf *bp; 4095 4096 a = ap; 4097 bp = a->a_bp; 4098 4099 /* 4100 * Cluster ops lock their component buffers but not the IO container. 4101 */ 4102 if ((bp->b_flags & B_CLUSTER) != 0) 4103 return; 4104 4105 if (panicstr == NULL && !BUF_ISLOCKED(bp)) { 4106 if (vfs_badlock_print) 4107 printf( 4108 "VOP_STRATEGY: bp is not locked but should be\n"); 4109 if (vfs_badlock_ddb) 4110 kdb_enter(KDB_WHY_VFSLOCK, "lock violation"); 4111 } 4112 #endif 4113 } 4114 4115 void 4116 vop_lock_pre(void *ap) 4117 { 4118 #ifdef DEBUG_VFS_LOCKS 4119 struct vop_lock1_args *a = ap; 4120 4121 if ((a->a_flags & LK_INTERLOCK) == 0) 4122 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_LOCK"); 4123 else 4124 ASSERT_VI_LOCKED(a->a_vp, "VOP_LOCK"); 4125 #endif 4126 } 4127 4128 void 4129 vop_lock_post(void *ap, int rc) 4130 { 4131 #ifdef DEBUG_VFS_LOCKS 4132 struct vop_lock1_args *a = ap; 4133 4134 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_LOCK"); 4135 if (rc == 0) 4136 ASSERT_VOP_LOCKED(a->a_vp, "VOP_LOCK"); 4137 #endif 4138 } 4139 4140 void 4141 vop_unlock_pre(void *ap) 4142 { 4143 #ifdef DEBUG_VFS_LOCKS 4144 struct vop_unlock_args *a = ap; 4145 4146 if (a->a_flags & LK_INTERLOCK) 4147 ASSERT_VI_LOCKED(a->a_vp, "VOP_UNLOCK"); 4148 ASSERT_VOP_LOCKED(a->a_vp, "VOP_UNLOCK"); 4149 #endif 4150 } 4151 4152 void 4153 vop_unlock_post(void *ap, int rc) 4154 { 4155 #ifdef DEBUG_VFS_LOCKS 4156 struct vop_unlock_args *a = ap; 4157 4158 if (a->a_flags & LK_INTERLOCK) 4159 ASSERT_VI_UNLOCKED(a->a_vp, "VOP_UNLOCK"); 4160 #endif 4161 } 4162 4163 void 4164 vop_create_post(void *ap, int rc) 4165 { 4166 struct vop_create_args *a = ap; 4167 4168 if (!rc) 4169 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 4170 } 4171 4172 void 4173 vop_deleteextattr_post(void *ap, int rc) 4174 { 4175 struct vop_deleteextattr_args *a = ap; 4176 4177 if (!rc) 4178 VFS_KNOTE_LOCKED(a->a_vp, NOTE_ATTRIB); 4179 } 4180 4181 void 4182 vop_link_post(void *ap, int rc) 4183 { 4184 struct vop_link_args *a = ap; 4185 4186 if (!rc) { 4187 VFS_KNOTE_LOCKED(a->a_vp, NOTE_LINK); 4188 VFS_KNOTE_LOCKED(a->a_tdvp, NOTE_WRITE); 4189 } 4190 } 4191 4192 void 4193 vop_mkdir_post(void *ap, int rc) 4194 { 4195 struct vop_mkdir_args *a = ap; 4196 4197 if (!rc) 4198 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE | NOTE_LINK); 4199 } 4200 4201 void 4202 vop_mknod_post(void *ap, int rc) 4203 { 4204 struct vop_mknod_args *a = ap; 4205 4206 if (!rc) 4207 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 4208 } 4209 4210 void 4211 vop_remove_post(void *ap, int rc) 4212 { 4213 struct vop_remove_args *a = ap; 4214 4215 if (!rc) { 4216 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 4217 VFS_KNOTE_LOCKED(a->a_vp, NOTE_DELETE); 4218 } 4219 } 4220 4221 void 4222 vop_rename_post(void *ap, int rc) 4223 { 4224 struct vop_rename_args *a = ap; 4225 4226 if (!rc) { 4227 VFS_KNOTE_UNLOCKED(a->a_fdvp, NOTE_WRITE); 4228 VFS_KNOTE_UNLOCKED(a->a_tdvp, NOTE_WRITE); 4229 VFS_KNOTE_UNLOCKED(a->a_fvp, NOTE_RENAME); 4230 if (a->a_tvp) 4231 VFS_KNOTE_UNLOCKED(a->a_tvp, NOTE_DELETE); 4232 } 4233 if (a->a_tdvp != a->a_fdvp) 4234 vdrop(a->a_fdvp); 4235 if (a->a_tvp != a->a_fvp) 4236 vdrop(a->a_fvp); 4237 vdrop(a->a_tdvp); 4238 if (a->a_tvp) 4239 vdrop(a->a_tvp); 4240 } 4241 4242 void 4243 vop_rmdir_post(void *ap, int rc) 4244 { 4245 struct vop_rmdir_args *a = ap; 4246 4247 if (!rc) { 4248 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE | NOTE_LINK); 4249 VFS_KNOTE_LOCKED(a->a_vp, NOTE_DELETE); 4250 } 4251 } 4252 4253 void 4254 vop_setattr_post(void *ap, int rc) 4255 { 4256 struct vop_setattr_args *a = ap; 4257 4258 if (!rc) 4259 VFS_KNOTE_LOCKED(a->a_vp, NOTE_ATTRIB); 4260 } 4261 4262 void 4263 vop_setextattr_post(void *ap, int rc) 4264 { 4265 struct vop_setextattr_args *a = ap; 4266 4267 if (!rc) 4268 VFS_KNOTE_LOCKED(a->a_vp, NOTE_ATTRIB); 4269 } 4270 4271 void 4272 vop_symlink_post(void *ap, int rc) 4273 { 4274 struct vop_symlink_args *a = ap; 4275 4276 if (!rc) 4277 VFS_KNOTE_LOCKED(a->a_dvp, NOTE_WRITE); 4278 } 4279 4280 static struct knlist fs_knlist; 4281 4282 static void 4283 vfs_event_init(void *arg) 4284 { 4285 knlist_init_mtx(&fs_knlist, NULL); 4286 } 4287 /* XXX - correct order? */ 4288 SYSINIT(vfs_knlist, SI_SUB_VFS, SI_ORDER_ANY, vfs_event_init, NULL); 4289 4290 void 4291 vfs_event_signal(fsid_t *fsid, uint32_t event, intptr_t data __unused) 4292 { 4293 4294 KNOTE_UNLOCKED(&fs_knlist, event); 4295 } 4296 4297 static int filt_fsattach(struct knote *kn); 4298 static void filt_fsdetach(struct knote *kn); 4299 static int filt_fsevent(struct knote *kn, long hint); 4300 4301 struct filterops fs_filtops = { 4302 .f_isfd = 0, 4303 .f_attach = filt_fsattach, 4304 .f_detach = filt_fsdetach, 4305 .f_event = filt_fsevent 4306 }; 4307 4308 static int 4309 filt_fsattach(struct knote *kn) 4310 { 4311 4312 kn->kn_flags |= EV_CLEAR; 4313 knlist_add(&fs_knlist, kn, 0); 4314 return (0); 4315 } 4316 4317 static void 4318 filt_fsdetach(struct knote *kn) 4319 { 4320 4321 knlist_remove(&fs_knlist, kn, 0); 4322 } 4323 4324 static int 4325 filt_fsevent(struct knote *kn, long hint) 4326 { 4327 4328 kn->kn_fflags |= hint; 4329 return (kn->kn_fflags != 0); 4330 } 4331 4332 static int 4333 sysctl_vfs_ctl(SYSCTL_HANDLER_ARGS) 4334 { 4335 struct vfsidctl vc; 4336 int error; 4337 struct mount *mp; 4338 4339 error = SYSCTL_IN(req, &vc, sizeof(vc)); 4340 if (error) 4341 return (error); 4342 if (vc.vc_vers != VFS_CTL_VERS1) 4343 return (EINVAL); 4344 mp = vfs_getvfs(&vc.vc_fsid); 4345 if (mp == NULL) 4346 return (ENOENT); 4347 /* ensure that a specific sysctl goes to the right filesystem. */ 4348 if (strcmp(vc.vc_fstypename, "*") != 0 && 4349 strcmp(vc.vc_fstypename, mp->mnt_vfc->vfc_name) != 0) { 4350 vfs_rel(mp); 4351 return (EINVAL); 4352 } 4353 VCTLTOREQ(&vc, req); 4354 error = VFS_SYSCTL(mp, vc.vc_op, req); 4355 vfs_rel(mp); 4356 return (error); 4357 } 4358 4359 SYSCTL_PROC(_vfs, OID_AUTO, ctl, CTLTYPE_OPAQUE | CTLFLAG_WR, 4360 NULL, 0, sysctl_vfs_ctl, "", 4361 "Sysctl by fsid"); 4362 4363 /* 4364 * Function to initialize a va_filerev field sensibly. 4365 * XXX: Wouldn't a random number make a lot more sense ?? 4366 */ 4367 u_quad_t 4368 init_va_filerev(void) 4369 { 4370 struct bintime bt; 4371 4372 getbinuptime(&bt); 4373 return (((u_quad_t)bt.sec << 32LL) | (bt.frac >> 32LL)); 4374 } 4375 4376 static int filt_vfsread(struct knote *kn, long hint); 4377 static int filt_vfswrite(struct knote *kn, long hint); 4378 static int filt_vfsvnode(struct knote *kn, long hint); 4379 static void filt_vfsdetach(struct knote *kn); 4380 static struct filterops vfsread_filtops = { 4381 .f_isfd = 1, 4382 .f_detach = filt_vfsdetach, 4383 .f_event = filt_vfsread 4384 }; 4385 static struct filterops vfswrite_filtops = { 4386 .f_isfd = 1, 4387 .f_detach = filt_vfsdetach, 4388 .f_event = filt_vfswrite 4389 }; 4390 static struct filterops vfsvnode_filtops = { 4391 .f_isfd = 1, 4392 .f_detach = filt_vfsdetach, 4393 .f_event = filt_vfsvnode 4394 }; 4395 4396 static void 4397 vfs_knllock(void *arg) 4398 { 4399 struct vnode *vp = arg; 4400 4401 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 4402 } 4403 4404 static void 4405 vfs_knlunlock(void *arg) 4406 { 4407 struct vnode *vp = arg; 4408 4409 VOP_UNLOCK(vp, 0); 4410 } 4411 4412 static void 4413 vfs_knl_assert_locked(void *arg) 4414 { 4415 #ifdef DEBUG_VFS_LOCKS 4416 struct vnode *vp = arg; 4417 4418 ASSERT_VOP_LOCKED(vp, "vfs_knl_assert_locked"); 4419 #endif 4420 } 4421 4422 static void 4423 vfs_knl_assert_unlocked(void *arg) 4424 { 4425 #ifdef DEBUG_VFS_LOCKS 4426 struct vnode *vp = arg; 4427 4428 ASSERT_VOP_UNLOCKED(vp, "vfs_knl_assert_unlocked"); 4429 #endif 4430 } 4431 4432 int 4433 vfs_kqfilter(struct vop_kqfilter_args *ap) 4434 { 4435 struct vnode *vp = ap->a_vp; 4436 struct knote *kn = ap->a_kn; 4437 struct knlist *knl; 4438 4439 switch (kn->kn_filter) { 4440 case EVFILT_READ: 4441 kn->kn_fop = &vfsread_filtops; 4442 break; 4443 case EVFILT_WRITE: 4444 kn->kn_fop = &vfswrite_filtops; 4445 break; 4446 case EVFILT_VNODE: 4447 kn->kn_fop = &vfsvnode_filtops; 4448 break; 4449 default: 4450 return (EINVAL); 4451 } 4452 4453 kn->kn_hook = (caddr_t)vp; 4454 4455 v_addpollinfo(vp); 4456 if (vp->v_pollinfo == NULL) 4457 return (ENOMEM); 4458 knl = &vp->v_pollinfo->vpi_selinfo.si_note; 4459 knlist_add(knl, kn, 0); 4460 4461 return (0); 4462 } 4463 4464 /* 4465 * Detach knote from vnode 4466 */ 4467 static void 4468 filt_vfsdetach(struct knote *kn) 4469 { 4470 struct vnode *vp = (struct vnode *)kn->kn_hook; 4471 4472 KASSERT(vp->v_pollinfo != NULL, ("Missing v_pollinfo")); 4473 knlist_remove(&vp->v_pollinfo->vpi_selinfo.si_note, kn, 0); 4474 } 4475 4476 /*ARGSUSED*/ 4477 static int 4478 filt_vfsread(struct knote *kn, long hint) 4479 { 4480 struct vnode *vp = (struct vnode *)kn->kn_hook; 4481 struct vattr va; 4482 int res; 4483 4484 /* 4485 * filesystem is gone, so set the EOF flag and schedule 4486 * the knote for deletion. 4487 */ 4488 if (hint == NOTE_REVOKE) { 4489 VI_LOCK(vp); 4490 kn->kn_flags |= (EV_EOF | EV_ONESHOT); 4491 VI_UNLOCK(vp); 4492 return (1); 4493 } 4494 4495 if (VOP_GETATTR(vp, &va, curthread->td_ucred)) 4496 return (0); 4497 4498 VI_LOCK(vp); 4499 kn->kn_data = va.va_size - kn->kn_fp->f_offset; 4500 res = (kn->kn_data != 0); 4501 VI_UNLOCK(vp); 4502 return (res); 4503 } 4504 4505 /*ARGSUSED*/ 4506 static int 4507 filt_vfswrite(struct knote *kn, long hint) 4508 { 4509 struct vnode *vp = (struct vnode *)kn->kn_hook; 4510 4511 VI_LOCK(vp); 4512 4513 /* 4514 * filesystem is gone, so set the EOF flag and schedule 4515 * the knote for deletion. 4516 */ 4517 if (hint == NOTE_REVOKE) 4518 kn->kn_flags |= (EV_EOF | EV_ONESHOT); 4519 4520 kn->kn_data = 0; 4521 VI_UNLOCK(vp); 4522 return (1); 4523 } 4524 4525 static int 4526 filt_vfsvnode(struct knote *kn, long hint) 4527 { 4528 struct vnode *vp = (struct vnode *)kn->kn_hook; 4529 int res; 4530 4531 VI_LOCK(vp); 4532 if (kn->kn_sfflags & hint) 4533 kn->kn_fflags |= hint; 4534 if (hint == NOTE_REVOKE) { 4535 kn->kn_flags |= EV_EOF; 4536 VI_UNLOCK(vp); 4537 return (1); 4538 } 4539 res = (kn->kn_fflags != 0); 4540 VI_UNLOCK(vp); 4541 return (res); 4542 } 4543 4544 int 4545 vfs_read_dirent(struct vop_readdir_args *ap, struct dirent *dp, off_t off) 4546 { 4547 int error; 4548 4549 if (dp->d_reclen > ap->a_uio->uio_resid) 4550 return (ENAMETOOLONG); 4551 error = uiomove(dp, dp->d_reclen, ap->a_uio); 4552 if (error) { 4553 if (ap->a_ncookies != NULL) { 4554 if (ap->a_cookies != NULL) 4555 free(ap->a_cookies, M_TEMP); 4556 ap->a_cookies = NULL; 4557 *ap->a_ncookies = 0; 4558 } 4559 return (error); 4560 } 4561 if (ap->a_ncookies == NULL) 4562 return (0); 4563 4564 KASSERT(ap->a_cookies, 4565 ("NULL ap->a_cookies value with non-NULL ap->a_ncookies!")); 4566 4567 *ap->a_cookies = realloc(*ap->a_cookies, 4568 (*ap->a_ncookies + 1) * sizeof(u_long), M_TEMP, M_WAITOK | M_ZERO); 4569 (*ap->a_cookies)[*ap->a_ncookies] = off; 4570 return (0); 4571 } 4572 4573 /* 4574 * Mark for update the access time of the file if the filesystem 4575 * supports VOP_MARKATIME. This functionality is used by execve and 4576 * mmap, so we want to avoid the I/O implied by directly setting 4577 * va_atime for the sake of efficiency. 4578 */ 4579 void 4580 vfs_mark_atime(struct vnode *vp, struct ucred *cred) 4581 { 4582 struct mount *mp; 4583 4584 mp = vp->v_mount; 4585 ASSERT_VOP_LOCKED(vp, "vfs_mark_atime"); 4586 if (mp != NULL && (mp->mnt_flag & (MNT_NOATIME | MNT_RDONLY)) == 0) 4587 (void)VOP_MARKATIME(vp); 4588 } 4589 4590 /* 4591 * The purpose of this routine is to remove granularity from accmode_t, 4592 * reducing it into standard unix access bits - VEXEC, VREAD, VWRITE, 4593 * VADMIN and VAPPEND. 4594 * 4595 * If it returns 0, the caller is supposed to continue with the usual 4596 * access checks using 'accmode' as modified by this routine. If it 4597 * returns nonzero value, the caller is supposed to return that value 4598 * as errno. 4599 * 4600 * Note that after this routine runs, accmode may be zero. 4601 */ 4602 int 4603 vfs_unixify_accmode(accmode_t *accmode) 4604 { 4605 /* 4606 * There is no way to specify explicit "deny" rule using 4607 * file mode or POSIX.1e ACLs. 4608 */ 4609 if (*accmode & VEXPLICIT_DENY) { 4610 *accmode = 0; 4611 return (0); 4612 } 4613 4614 /* 4615 * None of these can be translated into usual access bits. 4616 * Also, the common case for NFSv4 ACLs is to not contain 4617 * either of these bits. Caller should check for VWRITE 4618 * on the containing directory instead. 4619 */ 4620 if (*accmode & (VDELETE_CHILD | VDELETE)) 4621 return (EPERM); 4622 4623 if (*accmode & VADMIN_PERMS) { 4624 *accmode &= ~VADMIN_PERMS; 4625 *accmode |= VADMIN; 4626 } 4627 4628 /* 4629 * There is no way to deny VREAD_ATTRIBUTES, VREAD_ACL 4630 * or VSYNCHRONIZE using file mode or POSIX.1e ACL. 4631 */ 4632 *accmode &= ~(VSTAT_PERMS | VSYNCHRONIZE); 4633 4634 return (0); 4635 } 4636 4637 /* 4638 * These are helper functions for filesystems to traverse all 4639 * their vnodes. See MNT_VNODE_FOREACH_ALL() in sys/mount.h. 4640 * 4641 * This interface replaces MNT_VNODE_FOREACH. 4642 */ 4643 4644 MALLOC_DEFINE(M_VNODE_MARKER, "vnodemarker", "vnode marker"); 4645 4646 struct vnode * 4647 __mnt_vnode_next_all(struct vnode **mvp, struct mount *mp) 4648 { 4649 struct vnode *vp; 4650 4651 if (should_yield()) 4652 kern_yield(PRI_USER); 4653 MNT_ILOCK(mp); 4654 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch")); 4655 vp = TAILQ_NEXT(*mvp, v_nmntvnodes); 4656 while (vp != NULL && (vp->v_type == VMARKER || 4657 (vp->v_iflag & VI_DOOMED) != 0)) 4658 vp = TAILQ_NEXT(vp, v_nmntvnodes); 4659 4660 /* Check if we are done */ 4661 if (vp == NULL) { 4662 __mnt_vnode_markerfree_all(mvp, mp); 4663 /* MNT_IUNLOCK(mp); -- done in above function */ 4664 mtx_assert(MNT_MTX(mp), MA_NOTOWNED); 4665 return (NULL); 4666 } 4667 TAILQ_REMOVE(&mp->mnt_nvnodelist, *mvp, v_nmntvnodes); 4668 TAILQ_INSERT_AFTER(&mp->mnt_nvnodelist, vp, *mvp, v_nmntvnodes); 4669 VI_LOCK(vp); 4670 MNT_IUNLOCK(mp); 4671 return (vp); 4672 } 4673 4674 struct vnode * 4675 __mnt_vnode_first_all(struct vnode **mvp, struct mount *mp) 4676 { 4677 struct vnode *vp; 4678 4679 *mvp = malloc(sizeof(struct vnode), M_VNODE_MARKER, M_WAITOK | M_ZERO); 4680 MNT_ILOCK(mp); 4681 MNT_REF(mp); 4682 (*mvp)->v_type = VMARKER; 4683 4684 vp = TAILQ_FIRST(&mp->mnt_nvnodelist); 4685 while (vp != NULL && (vp->v_type == VMARKER || 4686 (vp->v_iflag & VI_DOOMED) != 0)) 4687 vp = TAILQ_NEXT(vp, v_nmntvnodes); 4688 4689 /* Check if we are done */ 4690 if (vp == NULL) { 4691 MNT_REL(mp); 4692 MNT_IUNLOCK(mp); 4693 free(*mvp, M_VNODE_MARKER); 4694 *mvp = NULL; 4695 return (NULL); 4696 } 4697 (*mvp)->v_mount = mp; 4698 TAILQ_INSERT_AFTER(&mp->mnt_nvnodelist, vp, *mvp, v_nmntvnodes); 4699 VI_LOCK(vp); 4700 MNT_IUNLOCK(mp); 4701 return (vp); 4702 } 4703 4704 4705 void 4706 __mnt_vnode_markerfree_all(struct vnode **mvp, struct mount *mp) 4707 { 4708 4709 if (*mvp == NULL) { 4710 MNT_IUNLOCK(mp); 4711 return; 4712 } 4713 4714 mtx_assert(MNT_MTX(mp), MA_OWNED); 4715 4716 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch")); 4717 TAILQ_REMOVE(&mp->mnt_nvnodelist, *mvp, v_nmntvnodes); 4718 MNT_REL(mp); 4719 MNT_IUNLOCK(mp); 4720 free(*mvp, M_VNODE_MARKER); 4721 *mvp = NULL; 4722 } 4723 4724 /* 4725 * These are helper functions for filesystems to traverse their 4726 * active vnodes. See MNT_VNODE_FOREACH_ACTIVE() in sys/mount.h 4727 */ 4728 static void 4729 mnt_vnode_markerfree_active(struct vnode **mvp, struct mount *mp) 4730 { 4731 4732 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch")); 4733 4734 MNT_ILOCK(mp); 4735 MNT_REL(mp); 4736 MNT_IUNLOCK(mp); 4737 free(*mvp, M_VNODE_MARKER); 4738 *mvp = NULL; 4739 } 4740 4741 static struct vnode * 4742 mnt_vnode_next_active(struct vnode **mvp, struct mount *mp) 4743 { 4744 struct vnode *vp, *nvp; 4745 4746 mtx_assert(&vnode_free_list_mtx, MA_OWNED); 4747 KASSERT((*mvp)->v_mount == mp, ("marker vnode mount list mismatch")); 4748 restart: 4749 vp = TAILQ_NEXT(*mvp, v_actfreelist); 4750 TAILQ_REMOVE(&mp->mnt_activevnodelist, *mvp, v_actfreelist); 4751 while (vp != NULL) { 4752 if (vp->v_type == VMARKER) { 4753 vp = TAILQ_NEXT(vp, v_actfreelist); 4754 continue; 4755 } 4756 if (!VI_TRYLOCK(vp)) { 4757 if (mp_ncpus == 1 || should_yield()) { 4758 TAILQ_INSERT_BEFORE(vp, *mvp, v_actfreelist); 4759 mtx_unlock(&vnode_free_list_mtx); 4760 kern_yield(PRI_USER); 4761 mtx_lock(&vnode_free_list_mtx); 4762 goto restart; 4763 } 4764 continue; 4765 } 4766 KASSERT(vp->v_type != VMARKER, ("locked marker %p", vp)); 4767 KASSERT(vp->v_mount == mp || vp->v_mount == NULL, 4768 ("alien vnode on the active list %p %p", vp, mp)); 4769 if (vp->v_mount == mp && (vp->v_iflag & VI_DOOMED) == 0) 4770 break; 4771 nvp = TAILQ_NEXT(vp, v_actfreelist); 4772 VI_UNLOCK(vp); 4773 vp = nvp; 4774 } 4775 4776 /* Check if we are done */ 4777 if (vp == NULL) { 4778 mtx_unlock(&vnode_free_list_mtx); 4779 mnt_vnode_markerfree_active(mvp, mp); 4780 return (NULL); 4781 } 4782 TAILQ_INSERT_AFTER(&mp->mnt_activevnodelist, vp, *mvp, v_actfreelist); 4783 mtx_unlock(&vnode_free_list_mtx); 4784 ASSERT_VI_LOCKED(vp, "active iter"); 4785 KASSERT((vp->v_iflag & VI_ACTIVE) != 0, ("Non-active vp %p", vp)); 4786 return (vp); 4787 } 4788 4789 struct vnode * 4790 __mnt_vnode_next_active(struct vnode **mvp, struct mount *mp) 4791 { 4792 4793 if (should_yield()) 4794 kern_yield(PRI_USER); 4795 mtx_lock(&vnode_free_list_mtx); 4796 return (mnt_vnode_next_active(mvp, mp)); 4797 } 4798 4799 struct vnode * 4800 __mnt_vnode_first_active(struct vnode **mvp, struct mount *mp) 4801 { 4802 struct vnode *vp; 4803 4804 *mvp = malloc(sizeof(struct vnode), M_VNODE_MARKER, M_WAITOK | M_ZERO); 4805 MNT_ILOCK(mp); 4806 MNT_REF(mp); 4807 MNT_IUNLOCK(mp); 4808 (*mvp)->v_type = VMARKER; 4809 (*mvp)->v_mount = mp; 4810 4811 mtx_lock(&vnode_free_list_mtx); 4812 vp = TAILQ_FIRST(&mp->mnt_activevnodelist); 4813 if (vp == NULL) { 4814 mtx_unlock(&vnode_free_list_mtx); 4815 mnt_vnode_markerfree_active(mvp, mp); 4816 return (NULL); 4817 } 4818 TAILQ_INSERT_BEFORE(vp, *mvp, v_actfreelist); 4819 return (mnt_vnode_next_active(mvp, mp)); 4820 } 4821 4822 void 4823 __mnt_vnode_markerfree_active(struct vnode **mvp, struct mount *mp) 4824 { 4825 4826 if (*mvp == NULL) 4827 return; 4828 4829 mtx_lock(&vnode_free_list_mtx); 4830 TAILQ_REMOVE(&mp->mnt_activevnodelist, *mvp, v_actfreelist); 4831 mtx_unlock(&vnode_free_list_mtx); 4832 mnt_vnode_markerfree_active(mvp, mp); 4833 } 4834