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 * 3. 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 * $FreeBSD: src/sys/kern/vfs_subr.c,v 1.249.2.30 2003/04/04 20:35:57 tegge Exp $ 36 */ 37 38 /* 39 * External virtual filesystem routines 40 */ 41 #include "opt_ddb.h" 42 #include "opt_inet.h" 43 #include "opt_inet6.h" 44 45 #include <sys/param.h> 46 #include <sys/systm.h> 47 #include <sys/uio.h> 48 #include <sys/buf.h> 49 #include <sys/conf.h> 50 #include <sys/dirent.h> 51 #include <sys/endian.h> 52 #include <sys/eventhandler.h> 53 #include <sys/fcntl.h> 54 #include <sys/file.h> 55 #include <sys/kernel.h> 56 #include <sys/kthread.h> 57 #include <sys/malloc.h> 58 #include <sys/mbuf.h> 59 #include <sys/mount.h> 60 #include <sys/caps.h> 61 #include <sys/proc.h> 62 #include <sys/reboot.h> 63 #include <sys/socket.h> 64 #include <sys/stat.h> 65 #include <sys/sysctl.h> 66 #include <sys/syslog.h> 67 #include <sys/unistd.h> 68 #include <sys/vmmeter.h> 69 #include <sys/vnode.h> 70 71 #include <machine/limits.h> 72 73 #include <vm/vm.h> 74 #include <vm/vm_object.h> 75 #include <vm/vm_extern.h> 76 #include <vm/vm_kern.h> 77 #include <vm/pmap.h> 78 #include <vm/vm_map.h> 79 #include <vm/vm_page.h> 80 #include <vm/vm_pager.h> 81 #include <vm/vnode_pager.h> 82 #include <vm/vm_zone.h> 83 84 #include <sys/buf2.h> 85 #include <vm/vm_page2.h> 86 87 #include <netinet/in.h> 88 89 static MALLOC_DEFINE(M_NETCRED, "Export Host", "Export host address structure"); 90 91 __read_mostly int numvnodes; 92 SYSCTL_INT(_debug, OID_AUTO, numvnodes, CTLFLAG_RD, &numvnodes, 0, 93 "Number of vnodes allocated"); 94 __read_mostly int verbose_reclaims; 95 SYSCTL_INT(_debug, OID_AUTO, verbose_reclaims, CTLFLAG_RD, &verbose_reclaims, 0, 96 "Output filename of reclaimed vnode(s)"); 97 98 __read_mostly enum vtype iftovt_tab[16] = { 99 VNON, VFIFO, VCHR, VNON, VDIR, VNON, VBLK, VNON, 100 VREG, VNON, VLNK, VNON, VSOCK, VNON, VNON, VBAD, 101 }; 102 __read_mostly int vttoif_tab[9] = { 103 0, S_IFREG, S_IFDIR, S_IFBLK, S_IFCHR, S_IFLNK, 104 S_IFSOCK, S_IFIFO, S_IFMT, 105 }; 106 107 static int reassignbufcalls; 108 SYSCTL_INT(_vfs, OID_AUTO, reassignbufcalls, CTLFLAG_RW, &reassignbufcalls, 109 0, "Number of times buffers have been reassigned to the proper list"); 110 111 __read_mostly static int check_buf_overlap = 2; /* invasive check */ 112 SYSCTL_INT(_vfs, OID_AUTO, check_buf_overlap, CTLFLAG_RW, &check_buf_overlap, 113 0, "Enable overlapping buffer checks"); 114 115 int nfs_mount_type = -1; 116 static struct lwkt_token spechash_token; 117 struct nfs_public nfs_pub; /* publicly exported FS */ 118 119 __read_mostly int maxvnodes; 120 SYSCTL_INT(_kern, KERN_MAXVNODES, maxvnodes, CTLFLAG_RW, 121 &maxvnodes, 0, "Maximum number of vnodes"); 122 123 static struct radix_node_head *vfs_create_addrlist_af(int af, 124 struct netexport *nep); 125 static void vclean_vxlocked(struct vnode *vp, int flags); 126 127 __read_mostly int prtactive = 0; /* 1 => print out reclaim of active vnodes */ 128 129 /* 130 * Red black tree functions 131 */ 132 static int rb_buf_compare(struct buf *b1, struct buf *b2); 133 RB_GENERATE2(buf_rb_tree, buf, b_rbnode, rb_buf_compare, off_t, b_loffset); 134 RB_GENERATE2(buf_rb_hash, buf, b_rbhash, rb_buf_compare, off_t, b_loffset); 135 136 static int 137 rb_buf_compare(struct buf *b1, struct buf *b2) 138 { 139 if (b1->b_loffset < b2->b_loffset) 140 return(-1); 141 if (b1->b_loffset > b2->b_loffset) 142 return(1); 143 return(0); 144 } 145 146 /* 147 * Initialize the vnode management data structures. 148 * 149 * Called from vfsinit() 150 */ 151 #define VNBREAKMEM1 (1L * 1024 * 1024 * 1024) 152 #define VNBREAKMEM2 (7L * 1024 * 1024 * 1024) 153 #define MINVNODES 2000 154 #define MAXVNODES 4000000 155 156 void 157 vfs_subr_init(void) 158 { 159 int factor1; /* Limit based on ram (x 2 above 1GB) */ 160 size_t freemem; 161 162 /* 163 * Size maxvnodes non-linearly to available memory. Don't bloat 164 * the count on low-memory systems. Scale up for systems with 165 * more than 1G and more than 8G of ram, but do so non-linearly 166 * because the value of a large maxvnodes count diminishes 167 * significantly beyond a certain point. 168 * 169 * The general minimum is maxproc * 8 (we want someone pushing 170 * up maxproc a lot to also get more vnodes). Usually maxproc 171 * does not affect this calculation. The KvaSize limitation also 172 * typically does not affect this calculation (it is just in case 173 * the kernel VM space is made much smaller than main memory, which 174 * should no longer happen on 64-bit systems). 175 * 176 * There isn't much of a point allowing maxvnodes to exceed a 177 * few million as modern filesystems cache pages in the 178 * underlying block device and not so much hanging off of VM 179 * objects. 180 * 181 * Also, VM objects, vnodes, and filesystem inode and other related 182 * structures have gotten a lot larger in recent years and the kernel 183 * memory use tends to scale with maxvnodes, so we don't want to bloat 184 * it too much. But neither do we want the max set too low because 185 * systems with large amounts of memory and cores are capable of 186 * doing a hell of a lot. 187 */ 188 factor1 = 80 * (sizeof(struct vm_object) + sizeof(struct vnode)); 189 190 freemem = (int64_t)vmstats.v_page_count * PAGE_SIZE; 191 192 maxvnodes = freemem / factor1; 193 if (freemem > VNBREAKMEM1) { 194 freemem -= VNBREAKMEM1; 195 if (freemem < VNBREAKMEM2) { 196 maxvnodes += freemem / factor1 / 2; 197 } else { 198 maxvnodes += VNBREAKMEM2 / factor1 / 2; 199 freemem -= VNBREAKMEM2; 200 maxvnodes += freemem / factor1 / 4; 201 } 202 } 203 maxvnodes = imax(maxvnodes, maxproc * 8); 204 maxvnodes = imin(maxvnodes, KvaSize / factor1); 205 maxvnodes = imin(maxvnodes, MAXVNODES); 206 maxvnodes = imax(maxvnodes, MINVNODES); 207 208 lwkt_token_init(&spechash_token, "spechash"); 209 } 210 211 /* 212 * Knob to control the precision of file timestamps: 213 * 214 * 0 = seconds only; nanoseconds zeroed. 215 * 1 = microseconds accurate to tick precision 216 * 2 = microseconds accurate to tick precision (default, hz >= 100) 217 * 3 = nanoseconds accurate to tick precision 218 * 4 = microseconds, maximum precision (default, hz < 100) 219 * 5 = nanoseconds, maximum precision 220 * 221 * Note that utimes() precision is microseconds because it takes a timeval 222 * structure, so its probably best to default to USEC or USEC_PRECISE, and 223 * not NSEC. 224 */ 225 enum { TSP_SEC, TSP_HZ, TSP_USEC, TSP_NSEC, 226 TSP_USEC_PRECISE, TSP_NSEC_PRECISE }; 227 228 __read_mostly static int timestamp_precision = -1; 229 SYSCTL_INT(_vfs, OID_AUTO, timestamp_precision, CTLFLAG_RW, 230 ×tamp_precision, 0, "Precision of file timestamps"); 231 232 /* 233 * Get a current timestamp. 234 * 235 * MPSAFE 236 */ 237 void 238 vfs_timestamp(struct timespec *tsp) 239 { 240 switch (timestamp_precision) { 241 case TSP_SEC: /* seconds precision */ 242 getnanotime(tsp); 243 tsp->tv_nsec = 0; 244 break; 245 case TSP_HZ: /* ticks precision (limit to microseconds) */ 246 getnanotime(tsp); 247 tsp->tv_nsec -= tsp->tv_nsec % 1000; 248 break; 249 default: 250 case TSP_USEC: /* microseconds (ticks precision) */ 251 getnanotime(tsp); 252 tsp->tv_nsec -= tsp->tv_nsec % 1000; 253 break; 254 case TSP_NSEC: /* nanoseconds (ticks precision) */ 255 getnanotime(tsp); 256 break; 257 case TSP_USEC_PRECISE: /* microseconds (high preceision) */ 258 nanotime(tsp); 259 tsp->tv_nsec -= tsp->tv_nsec % 1000; 260 break; 261 case TSP_NSEC_PRECISE: /* nanoseconds (high precision) */ 262 nanotime(tsp); 263 break; 264 } 265 } 266 267 /* 268 * Set vnode attributes to VNOVAL 269 */ 270 void 271 vattr_null(struct vattr *vap) 272 { 273 vap->va_type = VNON; 274 vap->va_size = VNOVAL; 275 vap->va_bytes = VNOVAL; 276 vap->va_mode = VNOVAL; 277 vap->va_nlink = VNOVAL; 278 vap->va_uid = VNOVAL; 279 vap->va_gid = VNOVAL; 280 vap->va_fsid = VNOVAL; 281 vap->va_fileid = VNOVAL; 282 vap->va_blocksize = VNOVAL; 283 vap->va_rmajor = VNOVAL; 284 vap->va_rminor = VNOVAL; 285 vap->va_atime.tv_sec = VNOVAL; 286 vap->va_atime.tv_nsec = VNOVAL; 287 vap->va_mtime.tv_sec = VNOVAL; 288 vap->va_mtime.tv_nsec = VNOVAL; 289 vap->va_ctime.tv_sec = VNOVAL; 290 vap->va_ctime.tv_nsec = VNOVAL; 291 vap->va_flags = VNOVAL; 292 vap->va_gen = VNOVAL; 293 vap->va_vaflags = 0; 294 /* va_*_uuid fields are only valid if related flags are set */ 295 } 296 297 /* 298 * Flush out and invalidate all buffers associated with a vnode. 299 * 300 * vp must be locked. 301 */ 302 static int vinvalbuf_bp(struct buf *bp, void *data); 303 304 struct vinvalbuf_bp_info { 305 struct vnode *vp; 306 int slptimeo; 307 int lkflags; 308 int flags; 309 int clean; 310 }; 311 312 int 313 vinvalbuf(struct vnode *vp, int flags, int slpflag, int slptimeo) 314 { 315 struct vinvalbuf_bp_info info; 316 vm_object_t object; 317 int error; 318 319 lwkt_gettoken(&vp->v_token); 320 321 /* 322 * If we are being asked to save, call fsync to ensure that the inode 323 * is updated. 324 */ 325 if (flags & V_SAVE) { 326 error = bio_track_wait(&vp->v_track_write, slpflag, slptimeo); 327 if (error) 328 goto done; 329 if (!RB_EMPTY(&vp->v_rbdirty_tree)) { 330 if ((error = VOP_FSYNC(vp, MNT_WAIT, 0)) != 0) 331 goto done; 332 #if 0 333 /* 334 * Dirty bufs may be left or generated via races 335 * in circumstances where vinvalbuf() is called on 336 * a vnode not undergoing reclamation. Only 337 * panic if we are trying to reclaim the vnode. 338 */ 339 if ((vp->v_flag & VRECLAIMED) && 340 (bio_track_active(&vp->v_track_write) || 341 !RB_EMPTY(&vp->v_rbdirty_tree))) { 342 panic("vinvalbuf: dirty bufs"); 343 } 344 #endif 345 } 346 } 347 info.slptimeo = slptimeo; 348 info.lkflags = LK_EXCLUSIVE | LK_SLEEPFAIL; 349 if (slpflag & PCATCH) 350 info.lkflags |= LK_PCATCH; 351 info.flags = flags; 352 info.vp = vp; 353 354 /* 355 * Flush the buffer cache until nothing is left, wait for all I/O 356 * to complete. At least one pass is required. We might block 357 * in the pip code so we have to re-check. Order is important. 358 */ 359 do { 360 /* 361 * Flush buffer cache 362 */ 363 if (!RB_EMPTY(&vp->v_rbclean_tree)) { 364 info.clean = 1; 365 error = RB_SCAN(buf_rb_tree, &vp->v_rbclean_tree, 366 NULL, vinvalbuf_bp, &info); 367 } 368 if (!RB_EMPTY(&vp->v_rbdirty_tree)) { 369 info.clean = 0; 370 error = RB_SCAN(buf_rb_tree, &vp->v_rbdirty_tree, 371 NULL, vinvalbuf_bp, &info); 372 } 373 374 /* 375 * Wait for I/O completion. 376 */ 377 bio_track_wait(&vp->v_track_write, 0, 0); 378 if ((object = vp->v_object) != NULL) 379 refcount_wait(&object->paging_in_progress, "vnvlbx"); 380 } while (bio_track_active(&vp->v_track_write) || 381 !RB_EMPTY(&vp->v_rbclean_tree) || 382 !RB_EMPTY(&vp->v_rbdirty_tree)); 383 384 /* 385 * Destroy the copy in the VM cache, too. 386 */ 387 if ((object = vp->v_object) != NULL) { 388 vm_object_page_remove(object, 0, 0, 389 (flags & V_SAVE) ? TRUE : FALSE); 390 } 391 392 if (!RB_EMPTY(&vp->v_rbdirty_tree) || !RB_EMPTY(&vp->v_rbclean_tree)) 393 panic("vinvalbuf: flush failed"); 394 if (!RB_EMPTY(&vp->v_rbhash_tree)) 395 panic("vinvalbuf: flush failed, buffers still present"); 396 error = 0; 397 done: 398 lwkt_reltoken(&vp->v_token); 399 return (error); 400 } 401 402 static int 403 vinvalbuf_bp(struct buf *bp, void *data) 404 { 405 struct vinvalbuf_bp_info *info = data; 406 int error; 407 408 if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_NOWAIT)) { 409 atomic_add_int(&bp->b_refs, 1); 410 error = BUF_TIMELOCK(bp, info->lkflags, 411 "vinvalbuf", info->slptimeo); 412 atomic_subtract_int(&bp->b_refs, 1); 413 if (error == 0) { 414 BUF_UNLOCK(bp); 415 error = ENOLCK; 416 } 417 if (error == ENOLCK) 418 return(0); 419 return (-error); 420 } 421 KKASSERT(bp->b_vp == info->vp); 422 423 /* 424 * Must check clean/dirty status after successfully locking as 425 * it may race. 426 */ 427 if ((info->clean && (bp->b_flags & B_DELWRI)) || 428 (info->clean == 0 && (bp->b_flags & B_DELWRI) == 0)) { 429 BUF_UNLOCK(bp); 430 return(0); 431 } 432 433 /* 434 * NOTE: NO B_LOCKED CHECK. Also no buf_checkwrite() 435 * check. This code will write out the buffer, period. 436 */ 437 bremfree(bp); 438 if (((bp->b_flags & (B_DELWRI | B_INVAL)) == B_DELWRI) && 439 (info->flags & V_SAVE)) { 440 cluster_awrite(bp); 441 } else if (info->flags & V_SAVE) { 442 /* 443 * Cannot set B_NOCACHE on a clean buffer as this will 444 * destroy the VM backing store which might actually 445 * be dirty (and unsynchronized). 446 */ 447 bp->b_flags |= (B_INVAL | B_RELBUF); 448 brelse(bp); 449 } else { 450 bp->b_flags |= (B_INVAL | B_NOCACHE | B_RELBUF); 451 brelse(bp); 452 } 453 return(0); 454 } 455 456 /* 457 * Truncate a file's buffer and pages to a specified length. This 458 * is in lieu of the old vinvalbuf mechanism, which performed unneeded 459 * sync activity. 460 * 461 * The vnode must be locked. 462 */ 463 static int vtruncbuf_bp_trunc_cmp(struct buf *bp, void *data); 464 static int vtruncbuf_bp_trunc(struct buf *bp, void *data); 465 static int vtruncbuf_bp_metasync_cmp(struct buf *bp, void *data); 466 static int vtruncbuf_bp_metasync(struct buf *bp, void *data); 467 468 struct vtruncbuf_info { 469 struct vnode *vp; 470 off_t truncloffset; 471 int clean; 472 }; 473 474 int 475 vtruncbuf(struct vnode *vp, off_t length, int blksize) 476 { 477 struct vtruncbuf_info info; 478 const char *filename; 479 int count; 480 481 /* 482 * Round up to the *next* block, then destroy the buffers in question. 483 * Since we are only removing some of the buffers we must rely on the 484 * scan count to determine whether a loop is necessary. 485 */ 486 if ((count = (int)(length % blksize)) != 0) 487 info.truncloffset = length + (blksize - count); 488 else 489 info.truncloffset = length; 490 info.vp = vp; 491 492 lwkt_gettoken(&vp->v_token); 493 do { 494 info.clean = 1; 495 count = RB_SCAN(buf_rb_tree, &vp->v_rbclean_tree, 496 vtruncbuf_bp_trunc_cmp, 497 vtruncbuf_bp_trunc, &info); 498 info.clean = 0; 499 count += RB_SCAN(buf_rb_tree, &vp->v_rbdirty_tree, 500 vtruncbuf_bp_trunc_cmp, 501 vtruncbuf_bp_trunc, &info); 502 } while(count); 503 504 /* 505 * For safety, fsync any remaining metadata if the file is not being 506 * truncated to 0. Since the metadata does not represent the entire 507 * dirty list we have to rely on the hit count to ensure that we get 508 * all of it. 509 */ 510 if (length > 0) { 511 do { 512 count = RB_SCAN(buf_rb_tree, &vp->v_rbdirty_tree, 513 vtruncbuf_bp_metasync_cmp, 514 vtruncbuf_bp_metasync, &info); 515 } while (count); 516 } 517 518 /* 519 * Clean out any left over VM backing store. 520 * 521 * It is possible to have in-progress I/O from buffers that were 522 * not part of the truncation. This should not happen if we 523 * are truncating to 0-length. 524 */ 525 vnode_pager_setsize(vp, length); 526 bio_track_wait(&vp->v_track_write, 0, 0); 527 528 /* 529 * Debugging only 530 */ 531 spin_lock(&vp->v_spin); 532 filename = TAILQ_FIRST(&vp->v_namecache) ? 533 TAILQ_FIRST(&vp->v_namecache)->nc_name : "?"; 534 spin_unlock(&vp->v_spin); 535 536 /* 537 * Make sure no buffers were instantiated while we were trying 538 * to clean out the remaining VM pages. This could occur due 539 * to busy dirty VM pages being flushed out to disk. 540 */ 541 do { 542 info.clean = 1; 543 count = RB_SCAN(buf_rb_tree, &vp->v_rbclean_tree, 544 vtruncbuf_bp_trunc_cmp, 545 vtruncbuf_bp_trunc, &info); 546 info.clean = 0; 547 count += RB_SCAN(buf_rb_tree, &vp->v_rbdirty_tree, 548 vtruncbuf_bp_trunc_cmp, 549 vtruncbuf_bp_trunc, &info); 550 if (count) { 551 kprintf("Warning: vtruncbuf(): Had to re-clean %d " 552 "left over buffers in %s\n", count, filename); 553 } 554 } while(count); 555 556 lwkt_reltoken(&vp->v_token); 557 558 return (0); 559 } 560 561 /* 562 * The callback buffer is beyond the new file EOF and must be destroyed. 563 * Note that the compare function must conform to the RB_SCAN's requirements. 564 */ 565 static 566 int 567 vtruncbuf_bp_trunc_cmp(struct buf *bp, void *data) 568 { 569 struct vtruncbuf_info *info = data; 570 571 if (bp->b_loffset >= info->truncloffset) 572 return(0); 573 return(-1); 574 } 575 576 static 577 int 578 vtruncbuf_bp_trunc(struct buf *bp, void *data) 579 { 580 struct vtruncbuf_info *info = data; 581 582 /* 583 * Do not try to use a buffer we cannot immediately lock, but sleep 584 * anyway to prevent a livelock. The code will loop until all buffers 585 * can be acted upon. 586 * 587 * We must always revalidate the buffer after locking it to deal 588 * with MP races. 589 */ 590 if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_NOWAIT)) { 591 atomic_add_int(&bp->b_refs, 1); 592 if (BUF_LOCK(bp, LK_EXCLUSIVE|LK_SLEEPFAIL) == 0) 593 BUF_UNLOCK(bp); 594 atomic_subtract_int(&bp->b_refs, 1); 595 } else if ((info->clean && (bp->b_flags & B_DELWRI)) || 596 (info->clean == 0 && (bp->b_flags & B_DELWRI) == 0) || 597 bp->b_vp != info->vp || 598 vtruncbuf_bp_trunc_cmp(bp, data)) { 599 BUF_UNLOCK(bp); 600 } else { 601 bremfree(bp); 602 bp->b_flags |= (B_INVAL | B_RELBUF | B_NOCACHE); 603 brelse(bp); 604 } 605 return(1); 606 } 607 608 /* 609 * Fsync all meta-data after truncating a file to be non-zero. Only metadata 610 * blocks (with a negative loffset) are scanned. 611 * Note that the compare function must conform to the RB_SCAN's requirements. 612 */ 613 static int 614 vtruncbuf_bp_metasync_cmp(struct buf *bp, void *data __unused) 615 { 616 if (bp->b_loffset < 0) 617 return(0); 618 return(1); 619 } 620 621 static int 622 vtruncbuf_bp_metasync(struct buf *bp, void *data) 623 { 624 struct vtruncbuf_info *info = data; 625 626 if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_NOWAIT)) { 627 atomic_add_int(&bp->b_refs, 1); 628 if (BUF_LOCK(bp, LK_EXCLUSIVE|LK_SLEEPFAIL) == 0) 629 BUF_UNLOCK(bp); 630 atomic_subtract_int(&bp->b_refs, 1); 631 } else if ((bp->b_flags & B_DELWRI) == 0 || 632 bp->b_vp != info->vp || 633 vtruncbuf_bp_metasync_cmp(bp, data)) { 634 BUF_UNLOCK(bp); 635 } else { 636 bremfree(bp); 637 if (bp->b_vp == info->vp) 638 bawrite(bp); 639 else 640 bwrite(bp); 641 } 642 return(1); 643 } 644 645 /* 646 * vfsync - implements a multipass fsync on a file which understands 647 * dependancies and meta-data. The passed vnode must be locked. The 648 * waitfor argument may be MNT_WAIT or MNT_NOWAIT, or MNT_LAZY. 649 * 650 * When fsyncing data asynchronously just do one consolidated pass starting 651 * with the most negative block number. This may not get all the data due 652 * to dependancies. 653 * 654 * When fsyncing data synchronously do a data pass, then a metadata pass, 655 * then do additional data+metadata passes to try to get all the data out. 656 * 657 * Caller must ref the vnode but does not have to lock it. 658 */ 659 static int vfsync_wait_output(struct vnode *vp, 660 int (*waitoutput)(struct vnode *, struct thread *)); 661 static int vfsync_dummy_cmp(struct buf *bp __unused, void *data __unused); 662 static int vfsync_data_only_cmp(struct buf *bp, void *data); 663 static int vfsync_meta_only_cmp(struct buf *bp, void *data); 664 static int vfsync_lazy_range_cmp(struct buf *bp, void *data); 665 static int vfsync_bp(struct buf *bp, void *data); 666 667 struct vfsync_info { 668 struct vnode *vp; 669 int fastpass; 670 int synchronous; 671 int syncdeps; 672 int lazycount; 673 int lazylimit; 674 int skippedbufs; 675 int (*checkdef)(struct buf *); 676 int (*cmpfunc)(struct buf *, void *); 677 }; 678 679 int 680 vfsync(struct vnode *vp, int waitfor, int passes, 681 int (*checkdef)(struct buf *), 682 int (*waitoutput)(struct vnode *, struct thread *)) 683 { 684 struct vfsync_info info; 685 int error; 686 687 bzero(&info, sizeof(info)); 688 info.vp = vp; 689 if ((info.checkdef = checkdef) == NULL) 690 info.syncdeps = 1; 691 692 lwkt_gettoken(&vp->v_token); 693 694 switch(waitfor) { 695 case MNT_LAZY | MNT_NOWAIT: 696 case MNT_LAZY: 697 /* 698 * Lazy (filesystem syncer typ) Asynchronous plus limit the 699 * number of data (not meta) pages we try to flush to 1MB. 700 * A non-zero return means that lazy limit was reached. 701 */ 702 info.lazylimit = 1024 * 1024; 703 info.syncdeps = 1; 704 info.cmpfunc = vfsync_lazy_range_cmp; 705 error = RB_SCAN(buf_rb_tree, &vp->v_rbdirty_tree, 706 vfsync_lazy_range_cmp, vfsync_bp, &info); 707 info.cmpfunc = vfsync_meta_only_cmp; 708 RB_SCAN(buf_rb_tree, &vp->v_rbdirty_tree, 709 vfsync_meta_only_cmp, vfsync_bp, &info); 710 if (error == 0) 711 vp->v_lazyw = 0; 712 else if (!RB_EMPTY(&vp->v_rbdirty_tree)) 713 vn_syncer_add(vp, 1); 714 error = 0; 715 break; 716 case MNT_NOWAIT: 717 /* 718 * Asynchronous. Do a data-only pass and a meta-only pass. 719 */ 720 info.syncdeps = 1; 721 info.cmpfunc = vfsync_data_only_cmp; 722 RB_SCAN(buf_rb_tree, &vp->v_rbdirty_tree, vfsync_data_only_cmp, 723 vfsync_bp, &info); 724 info.cmpfunc = vfsync_meta_only_cmp; 725 RB_SCAN(buf_rb_tree, &vp->v_rbdirty_tree, vfsync_meta_only_cmp, 726 vfsync_bp, &info); 727 error = 0; 728 break; 729 default: 730 /* 731 * Synchronous. Do a data-only pass, then a meta-data+data 732 * pass, then additional integrated passes to try to get 733 * all the dependancies flushed. 734 */ 735 info.cmpfunc = vfsync_data_only_cmp; 736 info.fastpass = 1; 737 RB_SCAN(buf_rb_tree, &vp->v_rbdirty_tree, vfsync_data_only_cmp, 738 vfsync_bp, &info); 739 info.fastpass = 0; 740 error = vfsync_wait_output(vp, waitoutput); 741 if (error == 0) { 742 info.skippedbufs = 0; 743 info.cmpfunc = vfsync_dummy_cmp; 744 RB_SCAN(buf_rb_tree, &vp->v_rbdirty_tree, NULL, 745 vfsync_bp, &info); 746 error = vfsync_wait_output(vp, waitoutput); 747 if (info.skippedbufs) { 748 kprintf("Warning: vfsync skipped %d dirty " 749 "buf%s in pass2!\n", 750 info.skippedbufs, 751 ((info.skippedbufs > 1) ? "s" : "")); 752 } 753 } 754 while (error == 0 && passes > 0 && 755 !RB_EMPTY(&vp->v_rbdirty_tree) 756 ) { 757 info.skippedbufs = 0; 758 if (--passes == 0) { 759 info.synchronous = 1; 760 info.syncdeps = 1; 761 } 762 info.cmpfunc = vfsync_dummy_cmp; 763 error = RB_SCAN(buf_rb_tree, &vp->v_rbdirty_tree, NULL, 764 vfsync_bp, &info); 765 if (error < 0) 766 error = -error; 767 info.syncdeps = 1; 768 if (error == 0) 769 error = vfsync_wait_output(vp, waitoutput); 770 if (info.skippedbufs && passes == 0) { 771 kprintf("Warning: vfsync skipped %d dirty " 772 "buf%s in final pass!\n", 773 info.skippedbufs, 774 ((info.skippedbufs > 1) ? "s" : "")); 775 } 776 } 777 #if 0 778 /* 779 * This case can occur normally because vnode lock might 780 * not be held. 781 */ 782 if (!RB_EMPTY(&vp->v_rbdirty_tree)) 783 kprintf("dirty bufs left after final pass\n"); 784 #endif 785 break; 786 } 787 lwkt_reltoken(&vp->v_token); 788 789 return(error); 790 } 791 792 static int 793 vfsync_wait_output(struct vnode *vp, 794 int (*waitoutput)(struct vnode *, struct thread *)) 795 { 796 int error; 797 798 error = bio_track_wait(&vp->v_track_write, 0, 0); 799 if (waitoutput) 800 error = waitoutput(vp, curthread); 801 return(error); 802 } 803 804 static int 805 vfsync_dummy_cmp(struct buf *bp __unused, void *data __unused) 806 { 807 return(0); 808 } 809 810 static int 811 vfsync_data_only_cmp(struct buf *bp, void *data) 812 { 813 if (bp->b_loffset < 0) 814 return(-1); 815 return(0); 816 } 817 818 static int 819 vfsync_meta_only_cmp(struct buf *bp, void *data) 820 { 821 if (bp->b_loffset < 0) 822 return(0); 823 return(1); 824 } 825 826 static int 827 vfsync_lazy_range_cmp(struct buf *bp, void *data) 828 { 829 struct vfsync_info *info = data; 830 831 if (bp->b_loffset < info->vp->v_lazyw) 832 return(-1); 833 return(0); 834 } 835 836 static int 837 vfsync_bp(struct buf *bp, void *data) 838 { 839 struct vfsync_info *info = data; 840 struct vnode *vp = info->vp; 841 int error; 842 843 if (info->fastpass) { 844 /* 845 * Ignore buffers that we cannot immediately lock. 846 */ 847 if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_NOWAIT)) { 848 /* 849 * Removed BUF_TIMELOCK(..., 1), even a 1-tick 850 * delay can mess up performance 851 * 852 * Another reason is that during a dirty-buffer 853 * scan a clustered write can start I/O on buffers 854 * ahead of the scan, causing the scan to not 855 * get a lock here. Usually this means the write 856 * is already in progress so, in fact, we *want* 857 * to skip the buffer. 858 */ 859 ++info->skippedbufs; 860 return(0); 861 } 862 } else if (info->synchronous == 0) { 863 /* 864 * Normal pass, give the buffer a little time to become 865 * available to us. 866 */ 867 if (BUF_TIMELOCK(bp, LK_EXCLUSIVE, "bflst2", hz / 10)) { 868 ++info->skippedbufs; 869 return(0); 870 } 871 } else { 872 /* 873 * Synchronous pass, give the buffer a lot of time before 874 * giving up. 875 */ 876 if (BUF_TIMELOCK(bp, LK_EXCLUSIVE, "bflst3", hz * 10)) { 877 ++info->skippedbufs; 878 return(0); 879 } 880 } 881 882 /* 883 * We must revalidate the buffer after locking. 884 */ 885 if ((bp->b_flags & B_DELWRI) == 0 || 886 bp->b_vp != info->vp || 887 info->cmpfunc(bp, data)) { 888 BUF_UNLOCK(bp); 889 return(0); 890 } 891 892 /* 893 * If syncdeps is not set we do not try to write buffers which have 894 * dependancies. 895 */ 896 if (!info->synchronous && info->syncdeps == 0 && info->checkdef(bp)) { 897 BUF_UNLOCK(bp); 898 return(0); 899 } 900 901 /* 902 * B_NEEDCOMMIT (primarily used by NFS) is a state where the buffer 903 * has been written but an additional handshake with the device 904 * is required before we can dispose of the buffer. We have no idea 905 * how to do this so we have to skip these buffers. 906 */ 907 if (bp->b_flags & B_NEEDCOMMIT) { 908 BUF_UNLOCK(bp); 909 return(0); 910 } 911 912 /* 913 * Ask bioops if it is ok to sync. If not the VFS may have 914 * set B_LOCKED so we have to cycle the buffer. 915 */ 916 if (LIST_FIRST(&bp->b_dep) != NULL && buf_checkwrite(bp)) { 917 bremfree(bp); 918 brelse(bp); 919 return(0); 920 } 921 922 if (info->synchronous) { 923 /* 924 * Synchronous flush. An error may be returned and will 925 * stop the scan. 926 */ 927 bremfree(bp); 928 error = bwrite(bp); 929 } else { 930 /* 931 * Asynchronous flush. We use the error return to support 932 * MNT_LAZY flushes. 933 * 934 * In low-memory situations we revert to synchronous 935 * operation. This should theoretically prevent the I/O 936 * path from exhausting memory in a non-recoverable way. 937 */ 938 vp->v_lazyw = bp->b_loffset; 939 bremfree(bp); 940 if (vm_paging_min()) { 941 /* low memory */ 942 info->lazycount += bp->b_bufsize; 943 bwrite(bp); 944 } else { 945 /* normal */ 946 info->lazycount += cluster_awrite(bp); 947 waitrunningbufspace(); 948 /*vm_wait_nominal();*/ 949 } 950 if (info->lazylimit && info->lazycount >= info->lazylimit) 951 error = 1; 952 else 953 error = 0; 954 } 955 return(-error); 956 } 957 958 /* 959 * Associate a buffer with a vnode. 960 * 961 * MPSAFE 962 */ 963 int 964 bgetvp(struct vnode *vp, struct buf *bp, int testsize) 965 { 966 KASSERT(bp->b_vp == NULL, ("bgetvp: not free")); 967 KKASSERT((bp->b_flags & (B_HASHED|B_DELWRI|B_VNCLEAN|B_VNDIRTY)) == 0); 968 969 /* 970 * Insert onto list for new vnode. 971 */ 972 lwkt_gettoken(&vp->v_token); 973 974 if (buf_rb_hash_RB_INSERT(&vp->v_rbhash_tree, bp)) { 975 lwkt_reltoken(&vp->v_token); 976 return (EEXIST); 977 } 978 979 /* 980 * Diagnostics (mainly for HAMMER debugging). Check for 981 * overlapping buffers. 982 */ 983 if (check_buf_overlap) { 984 struct buf *bx; 985 bx = buf_rb_hash_RB_PREV(bp); 986 if (bx) { 987 if (bx->b_loffset + bx->b_bufsize > bp->b_loffset) { 988 kprintf("bgetvp: overlapl %016jx/%d %016jx " 989 "bx %p bp %p\n", 990 (intmax_t)bx->b_loffset, 991 bx->b_bufsize, 992 (intmax_t)bp->b_loffset, 993 bx, bp); 994 if (check_buf_overlap > 1) 995 panic("bgetvp - overlapping buffer"); 996 } 997 } 998 bx = buf_rb_hash_RB_NEXT(bp); 999 if (bx) { 1000 if (bp->b_loffset + testsize > bx->b_loffset) { 1001 kprintf("bgetvp: overlapr %016jx/%d %016jx " 1002 "bp %p bx %p\n", 1003 (intmax_t)bp->b_loffset, 1004 testsize, 1005 (intmax_t)bx->b_loffset, 1006 bp, bx); 1007 if (check_buf_overlap > 1) 1008 panic("bgetvp - overlapping buffer"); 1009 } 1010 } 1011 } 1012 bp->b_vp = vp; 1013 bp->b_flags |= B_HASHED; 1014 bp->b_flags |= B_VNCLEAN; 1015 if (buf_rb_tree_RB_INSERT(&vp->v_rbclean_tree, bp)) 1016 panic("reassignbuf: dup lblk/clean vp %p bp %p", vp, bp); 1017 /*vhold(vp);*/ 1018 lwkt_reltoken(&vp->v_token); 1019 return(0); 1020 } 1021 1022 /* 1023 * Disassociate a buffer from a vnode. 1024 * 1025 * MPSAFE 1026 */ 1027 void 1028 brelvp(struct buf *bp) 1029 { 1030 struct vnode *vp; 1031 1032 KASSERT(bp->b_vp != NULL, ("brelvp: NULL")); 1033 1034 /* 1035 * Delete from old vnode list, if on one. 1036 */ 1037 vp = bp->b_vp; 1038 lwkt_gettoken(&vp->v_token); 1039 if (bp->b_flags & (B_VNDIRTY | B_VNCLEAN)) { 1040 if (bp->b_flags & B_VNDIRTY) 1041 buf_rb_tree_RB_REMOVE(&vp->v_rbdirty_tree, bp); 1042 else 1043 buf_rb_tree_RB_REMOVE(&vp->v_rbclean_tree, bp); 1044 bp->b_flags &= ~(B_VNDIRTY | B_VNCLEAN); 1045 } 1046 if (bp->b_flags & B_HASHED) { 1047 buf_rb_hash_RB_REMOVE(&vp->v_rbhash_tree, bp); 1048 bp->b_flags &= ~B_HASHED; 1049 } 1050 1051 /* 1052 * Only remove from synclist when no dirty buffers are left AND 1053 * the VFS has not flagged the vnode's inode as being dirty. 1054 */ 1055 if ((vp->v_flag & (VONWORKLST | VISDIRTY | VOBJDIRTY)) == VONWORKLST && 1056 RB_EMPTY(&vp->v_rbdirty_tree)) { 1057 vn_syncer_remove(vp, 0); 1058 } 1059 bp->b_vp = NULL; 1060 1061 lwkt_reltoken(&vp->v_token); 1062 1063 /*vdrop(vp);*/ 1064 } 1065 1066 /* 1067 * Reassign the buffer to the proper clean/dirty list based on B_DELWRI. 1068 * This routine is called when the state of the B_DELWRI bit is changed. 1069 * 1070 * Must be called with vp->v_token held. 1071 * MPSAFE 1072 */ 1073 void 1074 reassignbuf(struct buf *bp) 1075 { 1076 struct vnode *vp = bp->b_vp; 1077 int delay; 1078 1079 ASSERT_LWKT_TOKEN_HELD(&vp->v_token); 1080 ++reassignbufcalls; 1081 1082 /* 1083 * B_PAGING flagged buffers cannot be reassigned because their vp 1084 * is not fully linked in. 1085 */ 1086 if (bp->b_flags & B_PAGING) 1087 panic("cannot reassign paging buffer"); 1088 1089 if (bp->b_flags & B_DELWRI) { 1090 /* 1091 * Move to the dirty list, add the vnode to the worklist 1092 */ 1093 if (bp->b_flags & B_VNCLEAN) { 1094 buf_rb_tree_RB_REMOVE(&vp->v_rbclean_tree, bp); 1095 bp->b_flags &= ~B_VNCLEAN; 1096 } 1097 if ((bp->b_flags & B_VNDIRTY) == 0) { 1098 if (buf_rb_tree_RB_INSERT(&vp->v_rbdirty_tree, bp)) { 1099 panic("reassignbuf: dup lblk vp %p bp %p", 1100 vp, bp); 1101 } 1102 bp->b_flags |= B_VNDIRTY; 1103 } 1104 if ((vp->v_flag & VONWORKLST) == 0) { 1105 switch (vp->v_type) { 1106 case VDIR: 1107 delay = dirdelay; 1108 break; 1109 case VCHR: 1110 case VBLK: 1111 if (vp->v_rdev && 1112 vp->v_rdev->si_mountpoint != NULL) { 1113 delay = metadelay; 1114 break; 1115 } 1116 /* fall through */ 1117 default: 1118 delay = filedelay; 1119 } 1120 vn_syncer_add(vp, delay); 1121 } 1122 } else { 1123 /* 1124 * Move to the clean list, remove the vnode from the worklist 1125 * if no dirty blocks remain. 1126 */ 1127 if (bp->b_flags & B_VNDIRTY) { 1128 buf_rb_tree_RB_REMOVE(&vp->v_rbdirty_tree, bp); 1129 bp->b_flags &= ~B_VNDIRTY; 1130 } 1131 if ((bp->b_flags & B_VNCLEAN) == 0) { 1132 if (buf_rb_tree_RB_INSERT(&vp->v_rbclean_tree, bp)) { 1133 panic("reassignbuf: dup lblk vp %p bp %p", 1134 vp, bp); 1135 } 1136 bp->b_flags |= B_VNCLEAN; 1137 } 1138 1139 /* 1140 * Only remove from synclist when no dirty buffers are left 1141 * AND the VFS has not flagged the vnode's inode as being 1142 * dirty. 1143 */ 1144 if ((vp->v_flag & (VONWORKLST | VISDIRTY | VOBJDIRTY)) == 1145 VONWORKLST && 1146 RB_EMPTY(&vp->v_rbdirty_tree)) { 1147 vn_syncer_remove(vp, 0); 1148 } 1149 } 1150 } 1151 1152 /* 1153 * Create a vnode for a block device. Used for mounting the root file 1154 * system. 1155 * 1156 * A vref()'d vnode is returned. 1157 */ 1158 extern struct vop_ops *devfs_vnode_dev_vops_p; 1159 int 1160 bdevvp(cdev_t dev, struct vnode **vpp) 1161 { 1162 struct vnode *vp; 1163 struct vnode *nvp; 1164 int error; 1165 1166 if (dev == NULL) { 1167 *vpp = NULLVP; 1168 return (ENXIO); 1169 } 1170 error = getspecialvnode(VT_NON, NULL, &devfs_vnode_dev_vops_p, 1171 &nvp, 0, 0); 1172 if (error) { 1173 *vpp = NULLVP; 1174 return (error); 1175 } 1176 vp = nvp; 1177 vp->v_type = VCHR; 1178 #if 0 1179 vp->v_rdev = dev; 1180 #endif 1181 v_associate_rdev(vp, dev); 1182 vp->v_umajor = dev->si_umajor; 1183 vp->v_uminor = dev->si_uminor; 1184 vx_unlock(vp); 1185 *vpp = vp; 1186 return (0); 1187 } 1188 1189 int 1190 v_associate_rdev(struct vnode *vp, cdev_t dev) 1191 { 1192 if (dev == NULL) 1193 return(ENXIO); 1194 if (dev_is_good(dev) == 0) 1195 return(ENXIO); 1196 KKASSERT(vp->v_rdev == NULL); 1197 vp->v_rdev = reference_dev(dev); 1198 lwkt_gettoken(&spechash_token); 1199 SLIST_INSERT_HEAD(&dev->si_hlist, vp, v_cdevnext); 1200 lwkt_reltoken(&spechash_token); 1201 return(0); 1202 } 1203 1204 void 1205 v_release_rdev(struct vnode *vp) 1206 { 1207 cdev_t dev; 1208 1209 if ((dev = vp->v_rdev) != NULL) { 1210 lwkt_gettoken(&spechash_token); 1211 SLIST_REMOVE(&dev->si_hlist, vp, vnode, v_cdevnext); 1212 vp->v_rdev = NULL; 1213 release_dev(dev); 1214 lwkt_reltoken(&spechash_token); 1215 } 1216 } 1217 1218 /* 1219 * Add a vnode to the alias list hung off the cdev_t. We only associate 1220 * the device number with the vnode. The actual device is not associated 1221 * until the vnode is opened (usually in spec_open()), and will be 1222 * disassociated on last close. 1223 */ 1224 void 1225 addaliasu(struct vnode *nvp, int x, int y) 1226 { 1227 if (nvp->v_type != VBLK && nvp->v_type != VCHR) 1228 panic("addaliasu on non-special vnode"); 1229 nvp->v_umajor = x; 1230 nvp->v_uminor = y; 1231 } 1232 1233 /* 1234 * Simple call that a filesystem can make to try to get rid of a 1235 * vnode. It will fail if anyone is referencing the vnode (including 1236 * the caller). 1237 * 1238 * The filesystem can check whether its in-memory inode structure still 1239 * references the vp on return. 1240 * 1241 * May only be called if the vnode is in a known state (i.e. being prevented 1242 * from being deallocated by some other condition such as a vfs inode hold). 1243 * 1244 * This call might not succeed. 1245 */ 1246 void 1247 vclean_unlocked(struct vnode *vp) 1248 { 1249 vx_get(vp); 1250 if (VREFCNT(vp) <= 1) 1251 vgone_vxlocked(vp); 1252 vx_put(vp); 1253 } 1254 1255 /* 1256 * Disassociate a vnode from its underlying filesystem. 1257 * 1258 * The vnode must be VX locked and referenced. In all normal situations 1259 * there are no active references. If vclean_vxlocked() is called while 1260 * there are active references, the vnode is being ripped out and we have 1261 * to call VOP_CLOSE() as appropriate before we can reclaim it. 1262 */ 1263 static void 1264 vclean_vxlocked(struct vnode *vp, int flags) 1265 { 1266 int active; 1267 int n; 1268 vm_object_t object; 1269 struct namecache *ncp; 1270 1271 /* 1272 * If the vnode has already been reclaimed we have nothing to do. 1273 */ 1274 if (vp->v_flag & VRECLAIMED) 1275 return; 1276 1277 /* 1278 * Set flag to interlock operation, flag finalization to ensure 1279 * that the vnode winds up on the inactive list, and set v_act to 0. 1280 */ 1281 vsetflags(vp, VRECLAIMED); 1282 atomic_set_int(&vp->v_refcnt, VREF_FINALIZE); 1283 vp->v_act = 0; 1284 1285 if (verbose_reclaims) { 1286 if ((ncp = TAILQ_FIRST(&vp->v_namecache)) != NULL) 1287 kprintf("Debug: reclaim %p %s\n", vp, ncp->nc_name); 1288 } 1289 1290 /* 1291 * Scrap the vfs cache 1292 */ 1293 while (cache_inval_vp(vp, 0) != 0) { 1294 kprintf("Warning: vnode %p clean/cache_resolution " 1295 "race detected\n", vp); 1296 tsleep(vp, 0, "vclninv", 2); 1297 } 1298 1299 /* 1300 * Check to see if the vnode is in use. If so we have to reference it 1301 * before we clean it out so that its count cannot fall to zero and 1302 * generate a race against ourselves to recycle it. 1303 */ 1304 active = (VREFCNT(vp) > 0); 1305 1306 /* 1307 * Clean out any buffers associated with the vnode and destroy its 1308 * object, if it has one. 1309 */ 1310 vinvalbuf(vp, V_SAVE, 0, 0); 1311 1312 /* 1313 * If purging an active vnode (typically during a forced unmount 1314 * or reboot), it must be closed and deactivated before being 1315 * reclaimed. This isn't really all that safe, but what can 1316 * we do? XXX. 1317 * 1318 * Note that neither of these routines unlocks the vnode. 1319 */ 1320 if (active && (flags & DOCLOSE)) { 1321 while ((n = vp->v_opencount) != 0) { 1322 if (vp->v_writecount) 1323 VOP_CLOSE(vp, FWRITE|FNONBLOCK, NULL); 1324 else 1325 VOP_CLOSE(vp, FNONBLOCK, NULL); 1326 if (vp->v_opencount == n) { 1327 kprintf("Warning: unable to force-close" 1328 " vnode %p\n", vp); 1329 break; 1330 } 1331 } 1332 } 1333 1334 /* 1335 * If the vnode has not been deactivated, deactivated it. Deactivation 1336 * can create new buffers and VM pages so we have to call vinvalbuf() 1337 * again to make sure they all get flushed. 1338 * 1339 * This can occur if a file with a link count of 0 needs to be 1340 * truncated. 1341 * 1342 * If the vnode is already dead don't try to deactivate it. 1343 */ 1344 if ((vp->v_flag & VINACTIVE) == 0) { 1345 vsetflags(vp, VINACTIVE); 1346 if (vp->v_mount) 1347 VOP_INACTIVE(vp); 1348 vinvalbuf(vp, V_SAVE, 0, 0); 1349 } 1350 1351 /* 1352 * If the vnode has an object, destroy it. 1353 */ 1354 while ((object = vp->v_object) != NULL) { 1355 vm_object_hold(object); 1356 if (object == vp->v_object) 1357 break; 1358 vm_object_drop(object); 1359 } 1360 1361 if (object != NULL) { 1362 if (object->ref_count == 0) { 1363 if ((object->flags & OBJ_DEAD) == 0) 1364 vm_object_terminate(object); 1365 vm_object_drop(object); 1366 vclrflags(vp, VOBJBUF); 1367 } else { 1368 vm_pager_deallocate(object); 1369 vclrflags(vp, VOBJBUF); 1370 vm_object_drop(object); 1371 } 1372 } 1373 KKASSERT((vp->v_flag & VOBJBUF) == 0); 1374 1375 if (vp->v_flag & VOBJDIRTY) 1376 vclrobjdirty(vp); 1377 1378 /* 1379 * Reclaim the vnode if not already dead. 1380 */ 1381 if (vp->v_mount && VOP_RECLAIM(vp)) 1382 panic("vclean: cannot reclaim"); 1383 1384 /* 1385 * Done with purge, notify sleepers of the grim news. 1386 */ 1387 vp->v_ops = &dead_vnode_vops_p; 1388 vn_gone(vp); 1389 vp->v_tag = VT_NON; 1390 1391 /* 1392 * If we are destroying an active vnode, reactivate it now that 1393 * we have reassociated it with deadfs. This prevents the system 1394 * from crashing on the vnode due to it being unexpectedly marked 1395 * as inactive or reclaimed. 1396 */ 1397 if (active && (flags & DOCLOSE)) { 1398 vclrflags(vp, VINACTIVE | VRECLAIMED); 1399 } 1400 } 1401 1402 /* 1403 * Eliminate all activity associated with the requested vnode 1404 * and with all vnodes aliased to the requested vnode. 1405 * 1406 * The vnode must be referenced but should not be locked. 1407 */ 1408 int 1409 vrevoke(struct vnode *vp, struct ucred *cred) 1410 { 1411 struct vnode *vq; 1412 struct vnode *vqn; 1413 cdev_t dev; 1414 int error; 1415 1416 /* 1417 * If the vnode has a device association, scrap all vnodes associated 1418 * with the device. Don't let the device disappear on us while we 1419 * are scrapping the vnodes. 1420 * 1421 * The passed vp will probably show up in the list, do not VX lock 1422 * it twice! 1423 * 1424 * Releasing the vnode's rdev here can mess up specfs's call to 1425 * device close, so don't do it. The vnode has been disassociated 1426 * and the device will be closed after the last ref on the related 1427 * fp goes away (if not still open by e.g. the kernel). 1428 */ 1429 if (vp->v_type != VCHR) { 1430 error = fdrevoke(vp, DTYPE_VNODE, cred); 1431 return (error); 1432 } 1433 if ((dev = vp->v_rdev) == NULL) { 1434 return(0); 1435 } 1436 reference_dev(dev); 1437 lwkt_gettoken(&spechash_token); 1438 1439 restart: 1440 vqn = SLIST_FIRST(&dev->si_hlist); 1441 if (vqn) 1442 vhold(vqn); 1443 while ((vq = vqn) != NULL) { 1444 if (VREFCNT(vq) > 0) { 1445 vref(vq); 1446 fdrevoke(vq, DTYPE_VNODE, cred); 1447 /*v_release_rdev(vq);*/ 1448 vrele(vq); 1449 if (vq->v_rdev != dev) { 1450 vdrop(vq); 1451 goto restart; 1452 } 1453 } 1454 vqn = SLIST_NEXT(vq, v_cdevnext); 1455 if (vqn) 1456 vhold(vqn); 1457 vdrop(vq); 1458 } 1459 lwkt_reltoken(&spechash_token); 1460 dev_drevoke(dev); 1461 release_dev(dev); 1462 return (0); 1463 } 1464 1465 /* 1466 * This is called when the object underlying a vnode is being destroyed, 1467 * such as in a remove(). Try to recycle the vnode immediately if the 1468 * only active reference is our reference. 1469 * 1470 * Directory vnodes in the namecache with children cannot be immediately 1471 * recycled because numerous VOP_N*() ops require them to be stable. 1472 * 1473 * To avoid recursive recycling from VOP_INACTIVE implemenetations this 1474 * function is a NOP if VRECLAIMED is already set. 1475 */ 1476 int 1477 vrecycle(struct vnode *vp) 1478 { 1479 if (VREFCNT(vp) <= 1 && (vp->v_flag & VRECLAIMED) == 0) { 1480 if (cache_inval_vp_nonblock(vp)) 1481 return(0); 1482 vgone_vxlocked(vp); 1483 return (1); 1484 } 1485 return (0); 1486 } 1487 1488 /* 1489 * Return the maximum I/O size allowed for strategy calls on VP. 1490 * 1491 * If vp is VCHR or VBLK we dive the device, otherwise we use 1492 * the vp's mount info. 1493 * 1494 * The returned value is clamped at MAXPHYS as most callers cannot use 1495 * buffers larger than that size. 1496 */ 1497 int 1498 vmaxiosize(struct vnode *vp) 1499 { 1500 int maxiosize; 1501 1502 if (vp->v_type == VBLK || vp->v_type == VCHR) 1503 maxiosize = vp->v_rdev->si_iosize_max; 1504 else 1505 maxiosize = vp->v_mount->mnt_iosize_max; 1506 1507 if (maxiosize > MAXPHYS) 1508 maxiosize = MAXPHYS; 1509 return (maxiosize); 1510 } 1511 1512 /* 1513 * Eliminate all activity associated with a vnode in preparation for 1514 * destruction. 1515 * 1516 * The vnode must be VX locked and refd and will remain VX locked and refd 1517 * on return. This routine may be called with the vnode in any state, as 1518 * long as it is VX locked. The vnode will be cleaned out and marked 1519 * VRECLAIMED but will not actually be reused until all existing refs and 1520 * holds go away. 1521 * 1522 * NOTE: This routine may be called on a vnode which has not yet been 1523 * already been deactivated (VOP_INACTIVE), or on a vnode which has 1524 * already been reclaimed. 1525 * 1526 * This routine is not responsible for placing us back on the freelist. 1527 * Instead, it happens automatically when the caller releases the VX lock 1528 * (assuming there aren't any other references). 1529 */ 1530 void 1531 vgone_vxlocked(struct vnode *vp) 1532 { 1533 /* 1534 * assert that the VX lock is held. This is an absolute requirement 1535 * now for vgone_vxlocked() to be called. 1536 */ 1537 KKASSERT(lockinuse(&vp->v_lock)); 1538 1539 /* 1540 * Clean out the filesystem specific data and set the VRECLAIMED 1541 * bit. Also deactivate the vnode if necessary. 1542 * 1543 * The vnode should have automatically been removed from the syncer 1544 * list as syncer/dirty flags cleared during the cleaning. 1545 */ 1546 vclean_vxlocked(vp, DOCLOSE); 1547 1548 /* 1549 * Normally panic if the vnode is still dirty, unless we are doing 1550 * a forced unmount (tmpfs typically). 1551 */ 1552 if (vp->v_flag & VONWORKLST) { 1553 if (vp->v_mount->mnt_kern_flag & MNTK_UNMOUNTF) { 1554 /* force removal */ 1555 vn_syncer_remove(vp, 1); 1556 } else { 1557 panic("vp %p still dirty in vgone after flush", vp); 1558 } 1559 } 1560 1561 /* 1562 * Delete from old mount point vnode list, if on one. 1563 */ 1564 if (vp->v_mount != NULL) { 1565 KKASSERT(vp->v_data == NULL); 1566 insmntque(vp, NULL); 1567 } 1568 1569 /* 1570 * If special device, remove it from special device alias list 1571 * if it is on one. This should normally only occur if a vnode is 1572 * being revoked as the device should otherwise have been released 1573 * naturally. 1574 */ 1575 if ((vp->v_type == VBLK || vp->v_type == VCHR) && vp->v_rdev != NULL) { 1576 v_release_rdev(vp); 1577 } 1578 1579 /* 1580 * Set us to VBAD 1581 */ 1582 vp->v_type = VBAD; 1583 } 1584 1585 /* 1586 * Calculate the total number of references to a special device. This 1587 * routine may only be called for VBLK and VCHR vnodes since v_rdev is 1588 * an overloaded field. Since dev_from_devid() can now return NULL, we 1589 * have to check for a NULL v_rdev. 1590 */ 1591 int 1592 count_dev(cdev_t dev) 1593 { 1594 struct vnode *vp; 1595 int count = 0; 1596 1597 if (SLIST_FIRST(&dev->si_hlist)) { 1598 lwkt_gettoken(&spechash_token); 1599 SLIST_FOREACH(vp, &dev->si_hlist, v_cdevnext) { 1600 count += vp->v_opencount; 1601 } 1602 lwkt_reltoken(&spechash_token); 1603 } 1604 return(count); 1605 } 1606 1607 int 1608 vcount(struct vnode *vp) 1609 { 1610 if (vp->v_rdev == NULL) 1611 return(0); 1612 return(count_dev(vp->v_rdev)); 1613 } 1614 1615 /* 1616 * Initialize VMIO for a vnode. This routine MUST be called before a 1617 * VFS can issue buffer cache ops on a vnode. It is typically called 1618 * when a vnode is initialized from its inode. 1619 */ 1620 int 1621 vinitvmio(struct vnode *vp, off_t filesize, int blksize, int boff) 1622 { 1623 vm_object_t object; 1624 int error = 0; 1625 1626 object = vp->v_object; 1627 if (object) { 1628 vm_object_hold(object); 1629 KKASSERT(vp->v_object == object); 1630 } 1631 1632 if (object == NULL) { 1633 object = vnode_pager_alloc(vp, filesize, 0, 0, blksize, boff); 1634 1635 /* 1636 * Dereference the reference we just created. This assumes 1637 * that the object is associated with the vp. Allow it to 1638 * have zero refs. It cannot be destroyed as long as it 1639 * is associated with the vnode. 1640 */ 1641 vm_object_hold(object); 1642 atomic_add_int(&object->ref_count, -1); 1643 vrele(vp); 1644 } else { 1645 KKASSERT((object->flags & OBJ_DEAD) == 0); 1646 } 1647 KASSERT(vp->v_object != NULL, ("vinitvmio: NULL object")); 1648 vsetflags(vp, VOBJBUF); 1649 vm_object_drop(object); 1650 1651 return (error); 1652 } 1653 1654 1655 /* 1656 * Print out a description of a vnode. 1657 */ 1658 static char *typename[] = 1659 {"VNON", "VREG", "VDIR", "VBLK", "VCHR", "VLNK", "VSOCK", "VFIFO", "VBAD"}; 1660 1661 void 1662 vprint(char *label, struct vnode *vp) 1663 { 1664 char buf[96]; 1665 1666 if (label != NULL) 1667 kprintf("%s: %p: ", label, (void *)vp); 1668 else 1669 kprintf("%p: ", (void *)vp); 1670 kprintf("type %s, refcnt %08x, writecount %d, holdcnt %d,", 1671 typename[vp->v_type], 1672 vp->v_refcnt, vp->v_writecount, vp->v_auxrefs); 1673 buf[0] = '\0'; 1674 if (vp->v_flag & VROOT) 1675 strcat(buf, "|VROOT"); 1676 if (vp->v_flag & VPFSROOT) 1677 strcat(buf, "|VPFSROOT"); 1678 if (vp->v_flag & VTEXT) 1679 strcat(buf, "|VTEXT"); 1680 if (vp->v_flag & VSYSTEM) 1681 strcat(buf, "|VSYSTEM"); 1682 if (vp->v_flag & VOBJBUF) 1683 strcat(buf, "|VOBJBUF"); 1684 if (buf[0] != '\0') 1685 kprintf(" flags (%s)", &buf[1]); 1686 if (vp->v_data == NULL) { 1687 kprintf("\n"); 1688 } else { 1689 kprintf("\n\t"); 1690 VOP_PRINT(vp); 1691 } 1692 } 1693 1694 /* 1695 * Do the usual access checking. 1696 * file_mode, uid and gid are from the vnode in question, 1697 * while acc_mode and cred are from the VOP_ACCESS parameter list 1698 */ 1699 int 1700 vaccess(enum vtype type, mode_t file_mode, uid_t uid, gid_t gid, 1701 mode_t acc_mode, struct ucred *cred) 1702 { 1703 mode_t mask; 1704 int ismember; 1705 1706 /* 1707 * Super-user always gets read/write access, but execute access depends 1708 * on at least one execute bit being set. 1709 */ 1710 if (caps_priv_check(cred, SYSCAP_RESTRICTEDROOT) == 0) { 1711 if ((acc_mode & VEXEC) && type != VDIR && 1712 (file_mode & (S_IXUSR|S_IXGRP|S_IXOTH)) == 0) 1713 return (EACCES); 1714 return (0); 1715 } 1716 1717 mask = 0; 1718 1719 /* Otherwise, check the owner. */ 1720 if (cred->cr_uid == uid) { 1721 if (acc_mode & VEXEC) 1722 mask |= S_IXUSR; 1723 if (acc_mode & VREAD) 1724 mask |= S_IRUSR; 1725 if (acc_mode & VWRITE) 1726 mask |= S_IWUSR; 1727 return ((file_mode & mask) == mask ? 0 : EACCES); 1728 } 1729 1730 /* Otherwise, check the groups. */ 1731 ismember = groupmember(gid, cred); 1732 if (cred->cr_svgid == gid || ismember) { 1733 if (acc_mode & VEXEC) 1734 mask |= S_IXGRP; 1735 if (acc_mode & VREAD) 1736 mask |= S_IRGRP; 1737 if (acc_mode & VWRITE) 1738 mask |= S_IWGRP; 1739 return ((file_mode & mask) == mask ? 0 : EACCES); 1740 } 1741 1742 /* Otherwise, check everyone else. */ 1743 if (acc_mode & VEXEC) 1744 mask |= S_IXOTH; 1745 if (acc_mode & VREAD) 1746 mask |= S_IROTH; 1747 if (acc_mode & VWRITE) 1748 mask |= S_IWOTH; 1749 return ((file_mode & mask) == mask ? 0 : EACCES); 1750 } 1751 1752 #ifdef DDB 1753 #include <ddb/ddb.h> 1754 1755 static int db_show_locked_vnodes(struct mount *mp, void *data); 1756 1757 /* 1758 * List all of the locked vnodes in the system. 1759 * Called when debugging the kernel. 1760 */ 1761 DB_SHOW_COMMAND(lockedvnodes, lockedvnodes) 1762 { 1763 kprintf("Locked vnodes\n"); 1764 mountlist_scan(db_show_locked_vnodes, NULL, 1765 MNTSCAN_FORWARD|MNTSCAN_NOBUSY); 1766 } 1767 1768 static int 1769 db_show_locked_vnodes(struct mount *mp, void *data __unused) 1770 { 1771 struct vnode *vp; 1772 1773 TAILQ_FOREACH(vp, &mp->mnt_nvnodelist, v_nmntvnodes) { 1774 if (vn_islocked(vp)) 1775 vprint(NULL, vp); 1776 } 1777 return(0); 1778 } 1779 #endif 1780 1781 /* 1782 * Top level filesystem related information gathering. 1783 */ 1784 static int sysctl_ovfs_conf (SYSCTL_HANDLER_ARGS); 1785 1786 static int 1787 vfs_sysctl(SYSCTL_HANDLER_ARGS) 1788 { 1789 int *name = (int *)arg1 - 1; /* XXX */ 1790 u_int namelen = arg2 + 1; /* XXX */ 1791 struct vfsconf *vfsp; 1792 int maxtypenum; 1793 1794 #if 1 || defined(COMPAT_PRELITE2) 1795 /* Resolve ambiguity between VFS_VFSCONF and VFS_GENERIC. */ 1796 if (namelen == 1) 1797 return (sysctl_ovfs_conf(oidp, arg1, arg2, req)); 1798 #endif 1799 1800 #ifdef notyet 1801 /* all sysctl names at this level are at least name and field */ 1802 if (namelen < 2) 1803 return (ENOTDIR); /* overloaded */ 1804 if (name[0] != VFS_GENERIC) { 1805 vfsp = vfsconf_find_by_typenum(name[0]); 1806 if (vfsp == NULL) 1807 return (EOPNOTSUPP); 1808 return ((*vfsp->vfc_vfsops->vfs_sysctl)(&name[1], namelen - 1, 1809 oldp, oldlenp, newp, newlen, p)); 1810 } 1811 #endif 1812 switch (name[1]) { 1813 case VFS_MAXTYPENUM: 1814 if (namelen != 2) 1815 return (ENOTDIR); 1816 maxtypenum = vfsconf_get_maxtypenum(); 1817 return (SYSCTL_OUT(req, &maxtypenum, sizeof(maxtypenum))); 1818 case VFS_CONF: 1819 if (namelen != 3) 1820 return (ENOTDIR); /* overloaded */ 1821 vfsp = vfsconf_find_by_typenum(name[2]); 1822 if (vfsp == NULL) 1823 return (EOPNOTSUPP); 1824 return (SYSCTL_OUT(req, vfsp, sizeof *vfsp)); 1825 } 1826 return (EOPNOTSUPP); 1827 } 1828 1829 SYSCTL_NODE(_vfs, VFS_GENERIC, generic, CTLFLAG_RD, vfs_sysctl, 1830 "Generic filesystem"); 1831 1832 #if 1 || defined(COMPAT_PRELITE2) 1833 1834 static int 1835 sysctl_ovfs_conf_iter(struct vfsconf *vfsp, void *data) 1836 { 1837 int error; 1838 struct ovfsconf ovfs; 1839 struct sysctl_req *req = (struct sysctl_req*) data; 1840 1841 bzero(&ovfs, sizeof(ovfs)); 1842 ovfs.vfc_vfsops = vfsp->vfc_vfsops; /* XXX used as flag */ 1843 strcpy(ovfs.vfc_name, vfsp->vfc_name); 1844 ovfs.vfc_index = vfsp->vfc_typenum; 1845 ovfs.vfc_refcount = vfsp->vfc_refcount; 1846 ovfs.vfc_flags = vfsp->vfc_flags; 1847 error = SYSCTL_OUT(req, &ovfs, sizeof ovfs); 1848 if (error) 1849 return error; /* abort iteration with error code */ 1850 else 1851 return 0; /* continue iterating with next element */ 1852 } 1853 1854 static int 1855 sysctl_ovfs_conf(SYSCTL_HANDLER_ARGS) 1856 { 1857 return vfsconf_each(sysctl_ovfs_conf_iter, (void*)req); 1858 } 1859 1860 #endif /* 1 || COMPAT_PRELITE2 */ 1861 1862 /* 1863 * Check to see if a filesystem is mounted on a block device. 1864 */ 1865 int 1866 vfs_mountedon(struct vnode *vp) 1867 { 1868 cdev_t dev; 1869 1870 dev = vp->v_rdev; 1871 if (dev != NULL && dev->si_mountpoint) 1872 return (EBUSY); 1873 return (0); 1874 } 1875 1876 /* 1877 * Unmount all filesystems. The list is traversed in reverse order 1878 * of mounting to avoid dependencies. 1879 * 1880 * We want the umountall to be able to break out of its loop if a 1881 * failure occurs, after scanning all possible mounts, so the callback 1882 * returns 0 on error. 1883 * 1884 * NOTE: Do not call mountlist_remove(mp) on error any more, this will 1885 * confuse mountlist_scan()'s unbusy check. 1886 */ 1887 static int vfs_umountall_callback(struct mount *mp, void *data); 1888 1889 void 1890 vfs_unmountall(int halting) 1891 { 1892 int count; 1893 1894 do { 1895 count = mountlist_scan(vfs_umountall_callback, &halting, 1896 MNTSCAN_REVERSE|MNTSCAN_NOBUSY); 1897 } while (count); 1898 } 1899 1900 static 1901 int 1902 vfs_umountall_callback(struct mount *mp, void *data) 1903 { 1904 int error; 1905 int halting = *(int *)data; 1906 1907 /* 1908 * NOTE: When halting, dounmount will disconnect but leave 1909 * certain mount points intact. e.g. devfs. 1910 */ 1911 error = dounmount(mp, MNT_FORCE, halting); 1912 if (error) { 1913 kprintf("unmount of filesystem mounted from %s failed (", 1914 mp->mnt_stat.f_mntfromname); 1915 if (error == EBUSY) 1916 kprintf("BUSY)\n"); 1917 else 1918 kprintf("%d)\n", error); 1919 return 0; 1920 } else { 1921 return 1; 1922 } 1923 } 1924 1925 /* 1926 * Checks the mount flags for parameter mp and put the names comma-separated 1927 * into a string buffer buf with a size limit specified by len. 1928 * 1929 * It returns the number of bytes written into buf, and (*errorp) will be 1930 * set to 0, EINVAL (if passed length is 0), or ENOSPC (supplied buffer was 1931 * not large enough). The buffer will be 0-terminated if len was not 0. 1932 */ 1933 size_t 1934 vfs_flagstostr(int flags, const struct mountctl_opt *optp, 1935 char *buf, size_t len, int *errorp) 1936 { 1937 static const struct mountctl_opt optnames[] = { 1938 { MNT_RDONLY, "read-only" }, 1939 { MNT_SYNCHRONOUS, "synchronous" }, 1940 { MNT_NOEXEC, "noexec" }, 1941 { MNT_NOSUID, "nosuid" }, 1942 { MNT_NODEV, "nodev" }, 1943 { MNT_AUTOMOUNTED, "automounted" }, 1944 { MNT_ASYNC, "asynchronous" }, 1945 { MNT_SUIDDIR, "suiddir" }, 1946 { MNT_SOFTDEP, "soft-updates" }, 1947 { MNT_NOSYMFOLLOW, "nosymfollow" }, 1948 { MNT_TRIM, "trim" }, 1949 { MNT_NOATIME, "noatime" }, 1950 { MNT_NOCLUSTERR, "noclusterr" }, 1951 { MNT_NOCLUSTERW, "noclusterw" }, 1952 { MNT_EXRDONLY, "NFS read-only" }, 1953 { MNT_EXPORTED, "NFS exported" }, 1954 /* Remaining NFS flags could come here */ 1955 { MNT_LOCAL, "local" }, 1956 { MNT_QUOTA, "with-quotas" }, 1957 /* { MNT_ROOTFS, "rootfs" }, */ 1958 /* { MNT_IGNORE, "ignore" }, */ 1959 { 0, NULL} 1960 }; 1961 int bwritten; 1962 int bleft; 1963 int optlen; 1964 int actsize; 1965 1966 *errorp = 0; 1967 bwritten = 0; 1968 bleft = len - 1; /* leave room for trailing \0 */ 1969 1970 /* 1971 * Checks the size of the string. If it contains 1972 * any data, then we will append the new flags to 1973 * it. 1974 */ 1975 actsize = strlen(buf); 1976 if (actsize > 0) 1977 buf += actsize; 1978 1979 /* Default flags if no flags passed */ 1980 if (optp == NULL) 1981 optp = optnames; 1982 1983 if (bleft < 0) { /* degenerate case, 0-length buffer */ 1984 *errorp = EINVAL; 1985 return(0); 1986 } 1987 1988 for (; flags && optp->o_opt; ++optp) { 1989 if ((flags & optp->o_opt) == 0) 1990 continue; 1991 optlen = strlen(optp->o_name); 1992 if (bwritten || actsize > 0) { 1993 if (bleft < 2) { 1994 *errorp = ENOSPC; 1995 break; 1996 } 1997 buf[bwritten++] = ','; 1998 buf[bwritten++] = ' '; 1999 bleft -= 2; 2000 } 2001 if (bleft < optlen) { 2002 *errorp = ENOSPC; 2003 break; 2004 } 2005 bcopy(optp->o_name, buf + bwritten, optlen); 2006 bwritten += optlen; 2007 bleft -= optlen; 2008 flags &= ~optp->o_opt; 2009 } 2010 2011 /* 2012 * Space already reserved for trailing \0 2013 */ 2014 buf[bwritten] = 0; 2015 return (bwritten); 2016 } 2017 2018 /* 2019 * Build hash lists of net addresses and hang them off the mount point. 2020 * Called by ufs_mount() to set up the lists of export addresses. 2021 */ 2022 static int 2023 vfs_hang_addrlist(struct mount *mp, struct netexport *nep, 2024 const struct export_args *argp) 2025 { 2026 struct netcred *np; 2027 struct radix_node_head *rnh; 2028 int i; 2029 struct radix_node *rn; 2030 struct sockaddr *saddr, *smask = NULL; 2031 int error; 2032 2033 if (argp->ex_addrlen == 0) { 2034 if (mp->mnt_flag & MNT_DEFEXPORTED) 2035 return (EPERM); 2036 np = &nep->ne_defexported; 2037 np->netc_exflags = argp->ex_flags; 2038 np->netc_anon = argp->ex_anon; 2039 np->netc_anon.cr_ref = 1; 2040 mp->mnt_flag |= MNT_DEFEXPORTED; 2041 return (0); 2042 } 2043 2044 if (argp->ex_addrlen < 0 || argp->ex_addrlen > MLEN) 2045 return (EINVAL); 2046 if (argp->ex_masklen < 0 || argp->ex_masklen > MLEN) 2047 return (EINVAL); 2048 2049 i = sizeof(struct netcred) + argp->ex_addrlen + argp->ex_masklen; 2050 np = (struct netcred *)kmalloc(i, M_NETCRED, M_WAITOK | M_ZERO); 2051 saddr = (struct sockaddr *) (np + 1); 2052 if ((error = copyin(argp->ex_addr, (caddr_t) saddr, argp->ex_addrlen))) 2053 goto out; 2054 if (saddr->sa_len > argp->ex_addrlen) 2055 saddr->sa_len = argp->ex_addrlen; 2056 if (argp->ex_masklen) { 2057 smask = (struct sockaddr *)((caddr_t)saddr + argp->ex_addrlen); 2058 error = copyin(argp->ex_mask, (caddr_t)smask, argp->ex_masklen); 2059 if (error) 2060 goto out; 2061 if (smask->sa_len > argp->ex_masklen) 2062 smask->sa_len = argp->ex_masklen; 2063 } 2064 NE_LOCK(nep); 2065 if (nep->ne_maskhead == NULL) { 2066 if (!rn_inithead(&nep->ne_maskhead, NULL, 0)) { 2067 error = ENOBUFS; 2068 goto out; 2069 } 2070 } 2071 if ((rnh = vfs_create_addrlist_af(saddr->sa_family, nep)) == NULL) { 2072 error = ENOBUFS; 2073 goto out; 2074 } 2075 rn = rnh->rnh_addaddr(saddr, smask, rnh, np->netc_rnodes); 2076 NE_UNLOCK(nep); 2077 if (rn == NULL || np != (struct netcred *)rn) { /* already exists */ 2078 error = EPERM; 2079 goto out; 2080 } 2081 np->netc_exflags = argp->ex_flags; 2082 np->netc_anon = argp->ex_anon; 2083 np->netc_anon.cr_ref = 1; 2084 return (0); 2085 2086 out: 2087 kfree(np, M_NETCRED); 2088 return (error); 2089 } 2090 2091 /* 2092 * Free netcred structures installed in the netexport 2093 */ 2094 static void 2095 vfs_free_netcred(struct radix_node *rn) 2096 { 2097 struct netcred *np; 2098 2099 np = (struct netcred *)rn; 2100 kfree(np, M_NETCRED); 2101 } 2102 2103 static struct radix_node_head * 2104 vfs_create_addrlist_af(int af, struct netexport *nep) 2105 { 2106 struct radix_node_head *rnh = NULL; 2107 #if defined(INET) || defined(INET6) 2108 struct radix_node_head *maskhead = nep->ne_maskhead; 2109 int off; 2110 #endif 2111 2112 NE_ASSERT_LOCKED(nep); 2113 #if defined(INET) || defined(INET6) 2114 KKASSERT(maskhead != NULL); 2115 #endif 2116 switch (af) { 2117 #ifdef INET 2118 case AF_INET: 2119 if ((rnh = nep->ne_inethead) == NULL) { 2120 off = offsetof(struct sockaddr_in, sin_addr); 2121 if (!rn_inithead(&rnh, maskhead, off)) 2122 return (NULL); 2123 nep->ne_inethead = rnh; 2124 } 2125 break; 2126 #endif 2127 #ifdef INET6 2128 case AF_INET6: 2129 if ((rnh = nep->ne_inet6head) == NULL) { 2130 off = offsetof(struct sockaddr_in6, sin6_addr); 2131 if (!rn_inithead(&rnh, maskhead, off)) 2132 return (NULL); 2133 nep->ne_inet6head = rnh; 2134 } 2135 break; 2136 #endif 2137 } 2138 return (rnh); 2139 } 2140 2141 /* 2142 * Free the net address hash lists that are hanging off the mount points. 2143 */ 2144 static void 2145 vfs_free_addrlist(struct netexport *nep) 2146 { 2147 NE_LOCK(nep); 2148 if (nep->ne_inethead != NULL) { 2149 rn_flush(nep->ne_inethead, vfs_free_netcred); 2150 rn_freehead(nep->ne_inethead); 2151 nep->ne_inethead = NULL; 2152 } 2153 if (nep->ne_inet6head != NULL) { 2154 rn_flush(nep->ne_inet6head, vfs_free_netcred); 2155 rn_freehead(nep->ne_inet6head); 2156 nep->ne_inet6head = NULL; 2157 } 2158 if (nep->ne_maskhead != NULL) { 2159 rn_flush(nep->ne_maskhead, rn_freemask); 2160 rn_freehead(nep->ne_maskhead); 2161 nep->ne_maskhead = NULL; 2162 } 2163 NE_UNLOCK(nep); 2164 } 2165 2166 int 2167 vfs_export(struct mount *mp, struct netexport *nep, 2168 const struct export_args *argp) 2169 { 2170 int error; 2171 2172 if (argp->ex_flags & MNT_DELEXPORT) { 2173 if (mp->mnt_flag & MNT_EXPUBLIC) { 2174 vfs_setpublicfs(NULL, NULL, NULL); 2175 mp->mnt_flag &= ~MNT_EXPUBLIC; 2176 } 2177 vfs_free_addrlist(nep); 2178 mp->mnt_flag &= ~(MNT_EXPORTED | MNT_DEFEXPORTED); 2179 } 2180 if (argp->ex_flags & MNT_EXPORTED) { 2181 if (argp->ex_flags & MNT_EXPUBLIC) { 2182 if ((error = vfs_setpublicfs(mp, nep, argp)) != 0) 2183 return (error); 2184 mp->mnt_flag |= MNT_EXPUBLIC; 2185 } 2186 if ((error = vfs_hang_addrlist(mp, nep, argp))) 2187 return (error); 2188 mp->mnt_flag |= MNT_EXPORTED; 2189 } 2190 return (0); 2191 } 2192 2193 2194 /* 2195 * Set the publicly exported filesystem (WebNFS). Currently, only 2196 * one public filesystem is possible in the spec (RFC 2054 and 2055) 2197 */ 2198 int 2199 vfs_setpublicfs(struct mount *mp, struct netexport *nep, 2200 const struct export_args *argp) 2201 { 2202 int error; 2203 struct vnode *rvp; 2204 char *cp; 2205 2206 /* 2207 * mp == NULL -> invalidate the current info, the FS is 2208 * no longer exported. May be called from either vfs_export 2209 * or unmount, so check if it hasn't already been done. 2210 */ 2211 if (mp == NULL) { 2212 if (nfs_pub.np_valid) { 2213 nfs_pub.np_valid = 0; 2214 if (nfs_pub.np_index != NULL) { 2215 kfree(nfs_pub.np_index, M_TEMP); 2216 nfs_pub.np_index = NULL; 2217 } 2218 } 2219 return (0); 2220 } 2221 2222 /* 2223 * Only one allowed at a time. 2224 */ 2225 if (nfs_pub.np_valid != 0 && mp != nfs_pub.np_mount) 2226 return (EBUSY); 2227 2228 /* 2229 * Get real filehandle for root of exported FS. 2230 */ 2231 bzero((caddr_t)&nfs_pub.np_handle, sizeof(nfs_pub.np_handle)); 2232 nfs_pub.np_handle.fh_fsid = mp->mnt_stat.f_fsid; 2233 2234 if ((error = VFS_ROOT(mp, &rvp))) 2235 return (error); 2236 2237 if ((error = VFS_VPTOFH(rvp, &nfs_pub.np_handle.fh_fid))) 2238 return (error); 2239 2240 vput(rvp); 2241 2242 /* 2243 * If an indexfile was specified, pull it in. 2244 */ 2245 if (argp->ex_indexfile != NULL) { 2246 int namelen; 2247 2248 error = vn_get_namelen(rvp, &namelen); 2249 if (error) 2250 return (error); 2251 nfs_pub.np_index = kmalloc(namelen, M_TEMP, M_WAITOK); 2252 error = copyinstr(argp->ex_indexfile, nfs_pub.np_index, 2253 namelen, NULL); 2254 if (!error) { 2255 /* 2256 * Check for illegal filenames. 2257 */ 2258 for (cp = nfs_pub.np_index; *cp; cp++) { 2259 if (*cp == '/') { 2260 error = EINVAL; 2261 break; 2262 } 2263 } 2264 } 2265 if (error) { 2266 kfree(nfs_pub.np_index, M_TEMP); 2267 return (error); 2268 } 2269 } 2270 2271 nfs_pub.np_mount = mp; 2272 nfs_pub.np_valid = 1; 2273 return (0); 2274 } 2275 2276 struct netcred * 2277 vfs_export_lookup(struct mount *mp, struct netexport *nep, 2278 struct sockaddr *nam) 2279 { 2280 struct netcred *np; 2281 struct radix_node_head *rnh; 2282 struct sockaddr *saddr; 2283 2284 np = NULL; 2285 if (mp->mnt_flag & MNT_EXPORTED) { 2286 /* 2287 * Lookup in the export list first. 2288 */ 2289 NE_LOCK(nep); 2290 if (nam != NULL) { 2291 saddr = nam; 2292 switch (saddr->sa_family) { 2293 #ifdef INET 2294 case AF_INET: 2295 rnh = nep->ne_inethead; 2296 break; 2297 #endif 2298 #ifdef INET6 2299 case AF_INET6: 2300 rnh = nep->ne_inet6head; 2301 break; 2302 #endif 2303 default: 2304 rnh = NULL; 2305 } 2306 if (rnh != NULL) { 2307 np = (struct netcred *) 2308 rnh->rnh_matchaddr(saddr, rnh); 2309 if (np && np->netc_rnodes->rn_flags & RNF_ROOT) 2310 np = NULL; 2311 } 2312 } 2313 NE_UNLOCK(nep); 2314 /* 2315 * If no address match, use the default if it exists. 2316 */ 2317 if (np == NULL && mp->mnt_flag & MNT_DEFEXPORTED) 2318 np = &nep->ne_defexported; 2319 } 2320 return (np); 2321 } 2322 2323 /* 2324 * perform msync on all vnodes under a mount point. The mount point must 2325 * be locked. This code is also responsible for lazy-freeing unreferenced 2326 * vnodes whos VM objects no longer contain pages. 2327 * 2328 * NOTE: MNT_WAIT still skips vnodes in the VXLOCK state. 2329 * 2330 * NOTE: XXX VOP_PUTPAGES and friends requires that the vnode be locked, 2331 * but vnode_pager_putpages() doesn't lock the vnode. We have to do it 2332 * way up in this high level function. 2333 */ 2334 static int vfs_msync_scan1(struct mount *mp, struct vnode *vp, void *data); 2335 static int vfs_msync_scan2(struct mount *mp, struct vnode *vp, void *data); 2336 2337 void 2338 vfs_msync(struct mount *mp, int flags) 2339 { 2340 int vmsc_flags; 2341 2342 /* 2343 * tmpfs sets this flag to prevent msync(), sync, and the 2344 * filesystem periodic syncer from trying to flush VM pages 2345 * to swap. Only pure memory pressure flushes tmpfs VM pages 2346 * to swap. 2347 */ 2348 if (mp->mnt_kern_flag & MNTK_NOMSYNC) 2349 return; 2350 2351 /* 2352 * Ok, scan the vnodes for work. If the filesystem is using the 2353 * syncer thread feature we can use vsyncscan() instead of 2354 * vmntvnodescan(), which is much faster. 2355 */ 2356 vmsc_flags = VMSC_GETVP; 2357 if (flags != MNT_WAIT) 2358 vmsc_flags |= VMSC_NOWAIT; 2359 2360 if (mp->mnt_kern_flag & MNTK_THR_SYNC) { 2361 vsyncscan(mp, vmsc_flags, vfs_msync_scan2, 2362 (void *)(intptr_t)flags); 2363 } else { 2364 vmntvnodescan(mp, vmsc_flags, 2365 vfs_msync_scan1, vfs_msync_scan2, 2366 (void *)(intptr_t)flags); 2367 } 2368 } 2369 2370 /* 2371 * scan1 is a fast pre-check. There could be hundreds of thousands of 2372 * vnodes, we cannot afford to do anything heavy weight until we have a 2373 * fairly good indication that there is work to do. 2374 * 2375 * The new namecache holds the vnode for each v_namecache association 2376 * so allow these refs. 2377 */ 2378 static 2379 int 2380 vfs_msync_scan1(struct mount *mp, struct vnode *vp, void *data) 2381 { 2382 int flags = (int)(intptr_t)data; 2383 2384 if ((vp->v_flag & VRECLAIMED) == 0) { 2385 if (vp->v_auxrefs == vp->v_namecache_count && 2386 VREFCNT(vp) <= 0 && vp->v_object) { 2387 return(0); /* call scan2 */ 2388 } 2389 if ((mp->mnt_flag & MNT_RDONLY) == 0 && 2390 (vp->v_flag & VOBJDIRTY) && 2391 (flags == MNT_WAIT || vn_islocked(vp) == 0)) { 2392 return(0); /* call scan2 */ 2393 } 2394 } 2395 2396 /* 2397 * do not call scan2, continue the loop 2398 */ 2399 return(-1); 2400 } 2401 2402 /* 2403 * This callback is handed a locked vnode. 2404 */ 2405 static 2406 int 2407 vfs_msync_scan2(struct mount *mp, struct vnode *vp, void *data) 2408 { 2409 vm_object_t obj; 2410 int flags = (int)(intptr_t)data; 2411 int opcflags; 2412 2413 if (vp->v_flag & VRECLAIMED) 2414 return(0); 2415 2416 if ((mp->mnt_flag & MNT_RDONLY) == 0 && (vp->v_flag & VOBJDIRTY)) { 2417 if ((obj = vp->v_object) != NULL) { 2418 if (flags == MNT_WAIT) { 2419 /* 2420 * VFS_MSYNC is called with MNT_WAIT when 2421 * unmounting. 2422 */ 2423 opcflags = OBJPC_SYNC; 2424 } else if (vp->v_writecount || obj->ref_count) { 2425 /* 2426 * VFS_MSYNC is otherwise called via the 2427 * periodic filesystem sync or the 'sync' 2428 * command. Honor MADV_NOSYNC / MAP_NOSYNC 2429 * if the file is open for writing or memory 2430 * mapped. Pages flagged PG_NOSYNC will not 2431 * be automatically flushed at this time. 2432 * 2433 * The obj->ref_count test is not perfect 2434 * since temporary refs may be present, but 2435 * the periodic filesystem sync will ultimately 2436 * catch it if the file is not open and not 2437 * mapped. 2438 */ 2439 opcflags = OBJPC_NOSYNC; 2440 } else { 2441 /* 2442 * If the file is no longer open for writing 2443 * and also no longer mapped, do not honor 2444 * MAP_NOSYNC. That is, fully synchronize 2445 * the file. 2446 * 2447 * This still occurs on the periodic fs sync, 2448 * so frontend programs which turn the file 2449 * over quickly enough can still avoid the 2450 * sync, but ultimately we do want to flush 2451 * even MADV_NOSYNC pages once it is no longer 2452 * mapped or open for writing. 2453 */ 2454 opcflags = 0; 2455 } 2456 vm_object_page_clean(obj, 0, 0, opcflags); 2457 } 2458 } 2459 return(0); 2460 } 2461 2462 /* 2463 * Wake up anyone interested in vp because it is being revoked. 2464 */ 2465 void 2466 vn_gone(struct vnode *vp) 2467 { 2468 lwkt_gettoken(&vp->v_token); 2469 KNOTE(&vp->v_pollinfo.vpi_kqinfo.ki_note, NOTE_REVOKE); 2470 lwkt_reltoken(&vp->v_token); 2471 } 2472 2473 /* 2474 * extract the cdev_t from a VBLK or VCHR. The vnode must have been opened 2475 * (or v_rdev might be NULL). 2476 */ 2477 cdev_t 2478 vn_todev(struct vnode *vp) 2479 { 2480 if (vp->v_type != VBLK && vp->v_type != VCHR) 2481 return (NULL); 2482 KKASSERT(vp->v_rdev != NULL); 2483 return (vp->v_rdev); 2484 } 2485 2486 /* 2487 * Check if vnode represents a disk device. The vnode does not need to be 2488 * opened. 2489 * 2490 * MPALMOSTSAFE 2491 */ 2492 int 2493 vn_isdisk(struct vnode *vp, int *errp) 2494 { 2495 cdev_t dev; 2496 2497 if (vp->v_type != VCHR) { 2498 if (errp != NULL) 2499 *errp = ENOTBLK; 2500 return (0); 2501 } 2502 2503 dev = vp->v_rdev; 2504 2505 if (dev == NULL) { 2506 if (errp != NULL) 2507 *errp = ENXIO; 2508 return (0); 2509 } 2510 if (dev_is_good(dev) == 0) { 2511 if (errp != NULL) 2512 *errp = ENXIO; 2513 return (0); 2514 } 2515 if ((dev_dflags(dev) & D_DISK) == 0) { 2516 if (errp != NULL) 2517 *errp = ENOTBLK; 2518 return (0); 2519 } 2520 if (errp != NULL) 2521 *errp = 0; 2522 return (1); 2523 } 2524 2525 int 2526 vn_get_namelen(struct vnode *vp, int *namelen) 2527 { 2528 int error; 2529 register_t retval[2]; 2530 2531 error = VOP_PATHCONF(vp, _PC_NAME_MAX, retval); 2532 if (error) 2533 return (error); 2534 *namelen = (int)retval[0]; 2535 return (0); 2536 } 2537 2538 int 2539 vop_write_dirent(int *error, struct uio *uio, ino_t d_ino, uint8_t d_type, 2540 uint16_t d_namlen, const char *d_name) 2541 { 2542 struct dirent *dp; 2543 size_t len; 2544 2545 len = _DIRENT_RECLEN(d_namlen); 2546 if (len > uio->uio_resid) 2547 return(1); 2548 2549 dp = kmalloc(len, M_TEMP, M_WAITOK | M_ZERO); 2550 2551 dp->d_ino = d_ino; 2552 dp->d_namlen = d_namlen; 2553 dp->d_type = d_type; 2554 bcopy(d_name, dp->d_name, d_namlen); 2555 2556 *error = uiomove((caddr_t)dp, len, uio); 2557 2558 kfree(dp, M_TEMP); 2559 2560 return(0); 2561 } 2562 2563 void 2564 vn_mark_atime(struct vnode *vp, struct thread *td) 2565 { 2566 struct proc *p = td->td_proc; 2567 struct ucred *cred = p ? p->p_ucred : proc0.p_ucred; 2568 2569 if ((vp->v_mount->mnt_flag & (MNT_NOATIME | MNT_RDONLY)) == 0) { 2570 VOP_MARKATIME(vp, cred); 2571 } 2572 } 2573 2574 /* 2575 * Calculate the number of entries in an inode-related chained hash table. 2576 * With today's memory sizes, maxvnodes can wind up being a very large 2577 * number. There is no reason to waste memory, so tolerate some stacking. 2578 */ 2579 int 2580 vfs_inodehashsize(void) 2581 { 2582 int hsize; 2583 2584 hsize = 32; 2585 while (hsize < maxvnodes) 2586 hsize <<= 1; 2587 while (hsize > maxvnodes * 2) 2588 hsize >>= 1; /* nominal 2x stacking */ 2589 2590 if (maxvnodes > 1024 * 1024) 2591 hsize >>= 1; /* nominal 8x stacking */ 2592 2593 if (maxvnodes > 128 * 1024) 2594 hsize >>= 1; /* nominal 4x stacking */ 2595 2596 if (hsize < 16) 2597 hsize = 16; 2598 2599 return hsize; 2600 } 2601 2602 union _qcvt { 2603 quad_t qcvt; 2604 int32_t val[2]; 2605 }; 2606 2607 #define SETHIGH(q, h) { \ 2608 union _qcvt tmp; \ 2609 tmp.qcvt = (q); \ 2610 tmp.val[_QUAD_HIGHWORD] = (h); \ 2611 (q) = tmp.qcvt; \ 2612 } 2613 #define SETLOW(q, l) { \ 2614 union _qcvt tmp; \ 2615 tmp.qcvt = (q); \ 2616 tmp.val[_QUAD_LOWWORD] = (l); \ 2617 (q) = tmp.qcvt; \ 2618 } 2619 2620 u_quad_t 2621 init_va_filerev(void) 2622 { 2623 struct timeval tv; 2624 u_quad_t ret = 0; 2625 2626 getmicrouptime(&tv); 2627 SETHIGH(ret, tv.tv_sec); 2628 SETLOW(ret, tv.tv_usec * 4294); 2629 2630 return ret; 2631 } 2632 2633 /* 2634 * Set default timestamp_precision. If hz is reasonably high we go for 2635 * performance and limit vfs timestamps to microseconds with tick resolution. 2636 * If hz is too low, however, we lose a bit of performance to get a more 2637 * precise timestamp, because the mtime/ctime granularity might just be too 2638 * rough otherwise (for make and Makefile's, for example). 2639 */ 2640 static void 2641 vfs_ts_prec_init(void *dummy) 2642 { 2643 if (timestamp_precision < 0) { 2644 if (hz >= 100) 2645 timestamp_precision = TSP_USEC; 2646 else 2647 timestamp_precision = TSP_USEC_PRECISE; 2648 } 2649 } 2650 SYSINIT(vfs_ts_prec_init, SI_SUB_VFS, SI_ORDER_ANY, vfs_ts_prec_init, NULL); 2651