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