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sys/fs/tmpfs/tmpfs_subr.c
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1 /* $NetBSD: tmpfs_subr.c,v 1.35 2007/07/09 21:10:50 ad Exp $ */ 2 3 /*- 4 * SPDX-License-Identifier: BSD-2-Clause-NetBSD 5 * 6 * Copyright (c) 2005 The NetBSD Foundation, Inc. 7 * All rights reserved. 8 * 9 * This code is derived from software contributed to The NetBSD Foundation 10 * by Julio M. Merino Vidal, developed as part of Google's Summer of Code 11 * 2005 program. 12 * 13 * Redistribution and use in source and binary forms, with or without 14 * modification, are permitted provided that the following conditions 15 * are met: 16 * 1. Redistributions of source code must retain the above copyright 17 * notice, this list of conditions and the following disclaimer. 18 * 2. Redistributions in binary form must reproduce the above copyright 19 * notice, this list of conditions and the following disclaimer in the 20 * documentation and/or other materials provided with the distribution. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 23 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 24 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 25 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 26 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 27 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 28 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 29 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 30 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 31 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 32 * POSSIBILITY OF SUCH DAMAGE. 33 */ 34 35 /* 36 * Efficient memory file system supporting functions. 37 */ 38 #include <sys/cdefs.h> 39 __FBSDID("$FreeBSD$"); 40 41 #include <sys/param.h> 42 #include <sys/systm.h> 43 #include <sys/dirent.h> 44 #include <sys/fnv_hash.h> 45 #include <sys/lock.h> 46 #include <sys/limits.h> 47 #include <sys/mount.h> 48 #include <sys/namei.h> 49 #include <sys/priv.h> 50 #include <sys/proc.h> 51 #include <sys/random.h> 52 #include <sys/rwlock.h> 53 #include <sys/stat.h> 54 #include <sys/sysctl.h> 55 #include <sys/vnode.h> 56 #include <sys/vmmeter.h> 57 58 #include <vm/vm.h> 59 #include <vm/vm_param.h> 60 #include <vm/vm_object.h> 61 #include <vm/vm_page.h> 62 #include <vm/vm_pageout.h> 63 #include <vm/vm_pager.h> 64 #include <vm/vm_extern.h> 65 #include <vm/swap_pager.h> 66 67 #include <fs/tmpfs/tmpfs.h> 68 #include <fs/tmpfs/tmpfs_fifoops.h> 69 #include <fs/tmpfs/tmpfs_vnops.h> 70 71 SYSCTL_NODE(_vfs, OID_AUTO, tmpfs, CTLFLAG_RW, 0, "tmpfs file system"); 72 73 static long tmpfs_pages_reserved = TMPFS_PAGES_MINRESERVED; 74 75 static uma_zone_t tmpfs_dirent_pool; 76 static uma_zone_t tmpfs_node_pool; 77 78 static int 79 tmpfs_node_ctor(void *mem, int size, void *arg, int flags) 80 { 81 struct tmpfs_node *node; 82 83 node = mem; 84 node->tn_gen++; 85 node->tn_size = 0; 86 node->tn_status = 0; 87 node->tn_flags = 0; 88 node->tn_links = 0; 89 node->tn_vnode = NULL; 90 node->tn_vpstate = 0; 91 return (0); 92 } 93 94 static void 95 tmpfs_node_dtor(void *mem, int size, void *arg) 96 { 97 struct tmpfs_node *node; 98 99 node = mem; 100 node->tn_type = VNON; 101 } 102 103 static int 104 tmpfs_node_init(void *mem, int size, int flags) 105 { 106 struct tmpfs_node *node; 107 108 node = mem; 109 node->tn_id = 0; 110 mtx_init(&node->tn_interlock, "tmpfsni", NULL, MTX_DEF); 111 node->tn_gen = arc4random(); 112 return (0); 113 } 114 115 static void 116 tmpfs_node_fini(void *mem, int size) 117 { 118 struct tmpfs_node *node; 119 120 node = mem; 121 mtx_destroy(&node->tn_interlock); 122 } 123 124 void 125 tmpfs_subr_init(void) 126 { 127 tmpfs_dirent_pool = uma_zcreate("TMPFS dirent", 128 sizeof(struct tmpfs_dirent), NULL, NULL, NULL, NULL, 129 UMA_ALIGN_PTR, 0); 130 tmpfs_node_pool = uma_zcreate("TMPFS node", 131 sizeof(struct tmpfs_node), tmpfs_node_ctor, tmpfs_node_dtor, 132 tmpfs_node_init, tmpfs_node_fini, UMA_ALIGN_PTR, 0); 133 } 134 135 void 136 tmpfs_subr_uninit(void) 137 { 138 uma_zdestroy(tmpfs_node_pool); 139 uma_zdestroy(tmpfs_dirent_pool); 140 } 141 142 static int 143 sysctl_mem_reserved(SYSCTL_HANDLER_ARGS) 144 { 145 int error; 146 long pages, bytes; 147 148 pages = *(long *)arg1; 149 bytes = pages * PAGE_SIZE; 150 151 error = sysctl_handle_long(oidp, &bytes, 0, req); 152 if (error || !req->newptr) 153 return (error); 154 155 pages = bytes / PAGE_SIZE; 156 if (pages < TMPFS_PAGES_MINRESERVED) 157 return (EINVAL); 158 159 *(long *)arg1 = pages; 160 return (0); 161 } 162 163 SYSCTL_PROC(_vfs_tmpfs, OID_AUTO, memory_reserved, CTLTYPE_LONG|CTLFLAG_RW, 164 &tmpfs_pages_reserved, 0, sysctl_mem_reserved, "L", 165 "Amount of available memory and swap below which tmpfs growth stops"); 166 167 static __inline int tmpfs_dirtree_cmp(struct tmpfs_dirent *a, 168 struct tmpfs_dirent *b); 169 RB_PROTOTYPE_STATIC(tmpfs_dir, tmpfs_dirent, uh.td_entries, tmpfs_dirtree_cmp); 170 171 size_t 172 tmpfs_mem_avail(void) 173 { 174 vm_ooffset_t avail; 175 176 avail = swap_pager_avail + vm_free_count() - tmpfs_pages_reserved; 177 if (__predict_false(avail < 0)) 178 avail = 0; 179 return (avail); 180 } 181 182 size_t 183 tmpfs_pages_used(struct tmpfs_mount *tmp) 184 { 185 const size_t node_size = sizeof(struct tmpfs_node) + 186 sizeof(struct tmpfs_dirent); 187 size_t meta_pages; 188 189 meta_pages = howmany((uintmax_t)tmp->tm_nodes_inuse * node_size, 190 PAGE_SIZE); 191 return (meta_pages + tmp->tm_pages_used); 192 } 193 194 static size_t 195 tmpfs_pages_check_avail(struct tmpfs_mount *tmp, size_t req_pages) 196 { 197 if (tmpfs_mem_avail() < req_pages) 198 return (0); 199 200 if (tmp->tm_pages_max != ULONG_MAX && 201 tmp->tm_pages_max < req_pages + tmpfs_pages_used(tmp)) 202 return (0); 203 204 return (1); 205 } 206 207 void 208 tmpfs_ref_node(struct tmpfs_node *node) 209 { 210 211 TMPFS_NODE_LOCK(node); 212 tmpfs_ref_node_locked(node); 213 TMPFS_NODE_UNLOCK(node); 214 } 215 216 void 217 tmpfs_ref_node_locked(struct tmpfs_node *node) 218 { 219 220 TMPFS_NODE_ASSERT_LOCKED(node); 221 KASSERT(node->tn_refcount > 0, ("node %p zero refcount", node)); 222 KASSERT(node->tn_refcount < UINT_MAX, ("node %p refcount %u", node, 223 node->tn_refcount)); 224 node->tn_refcount++; 225 } 226 227 /* 228 * Allocates a new node of type 'type' inside the 'tmp' mount point, with 229 * its owner set to 'uid', its group to 'gid' and its mode set to 'mode', 230 * using the credentials of the process 'p'. 231 * 232 * If the node type is set to 'VDIR', then the parent parameter must point 233 * to the parent directory of the node being created. It may only be NULL 234 * while allocating the root node. 235 * 236 * If the node type is set to 'VBLK' or 'VCHR', then the rdev parameter 237 * specifies the device the node represents. 238 * 239 * If the node type is set to 'VLNK', then the parameter target specifies 240 * the file name of the target file for the symbolic link that is being 241 * created. 242 * 243 * Note that new nodes are retrieved from the available list if it has 244 * items or, if it is empty, from the node pool as long as there is enough 245 * space to create them. 246 * 247 * Returns zero on success or an appropriate error code on failure. 248 */ 249 int 250 tmpfs_alloc_node(struct mount *mp, struct tmpfs_mount *tmp, enum vtype type, 251 uid_t uid, gid_t gid, mode_t mode, struct tmpfs_node *parent, 252 char *target, dev_t rdev, struct tmpfs_node **node) 253 { 254 struct tmpfs_node *nnode; 255 vm_object_t obj; 256 257 /* If the root directory of the 'tmp' file system is not yet 258 * allocated, this must be the request to do it. */ 259 MPASS(IMPLIES(tmp->tm_root == NULL, parent == NULL && type == VDIR)); 260 KASSERT(tmp->tm_root == NULL || mp->mnt_writeopcount > 0, 261 ("creating node not under vn_start_write")); 262 263 MPASS(IFF(type == VLNK, target != NULL)); 264 MPASS(IFF(type == VBLK || type == VCHR, rdev != VNOVAL)); 265 266 if (tmp->tm_nodes_inuse >= tmp->tm_nodes_max) 267 return (ENOSPC); 268 if (tmpfs_pages_check_avail(tmp, 1) == 0) 269 return (ENOSPC); 270 271 if ((mp->mnt_kern_flag & MNTK_UNMOUNT) != 0) { 272 /* 273 * When a new tmpfs node is created for fully 274 * constructed mount point, there must be a parent 275 * node, which vnode is locked exclusively. As 276 * consequence, if the unmount is executing in 277 * parallel, vflush() cannot reclaim the parent vnode. 278 * Due to this, the check for MNTK_UNMOUNT flag is not 279 * racy: if we did not see MNTK_UNMOUNT flag, then tmp 280 * cannot be destroyed until node construction is 281 * finished and the parent vnode unlocked. 282 * 283 * Tmpfs does not need to instantiate new nodes during 284 * unmount. 285 */ 286 return (EBUSY); 287 } 288 if ((mp->mnt_kern_flag & MNT_RDONLY) != 0) 289 return (EROFS); 290 291 nnode = uma_zalloc_arg(tmpfs_node_pool, tmp, M_WAITOK); 292 293 /* Generic initialization. */ 294 nnode->tn_type = type; 295 vfs_timestamp(&nnode->tn_atime); 296 nnode->tn_birthtime = nnode->tn_ctime = nnode->tn_mtime = 297 nnode->tn_atime; 298 nnode->tn_uid = uid; 299 nnode->tn_gid = gid; 300 nnode->tn_mode = mode; 301 nnode->tn_id = alloc_unr64(&tmp->tm_ino_unr); 302 nnode->tn_refcount = 1; 303 304 /* Type-specific initialization. */ 305 switch (nnode->tn_type) { 306 case VBLK: 307 case VCHR: 308 nnode->tn_rdev = rdev; 309 break; 310 311 case VDIR: 312 RB_INIT(&nnode->tn_dir.tn_dirhead); 313 LIST_INIT(&nnode->tn_dir.tn_dupindex); 314 MPASS(parent != nnode); 315 MPASS(IMPLIES(parent == NULL, tmp->tm_root == NULL)); 316 nnode->tn_dir.tn_parent = (parent == NULL) ? nnode : parent; 317 nnode->tn_dir.tn_readdir_lastn = 0; 318 nnode->tn_dir.tn_readdir_lastp = NULL; 319 nnode->tn_links++; 320 TMPFS_NODE_LOCK(nnode->tn_dir.tn_parent); 321 nnode->tn_dir.tn_parent->tn_links++; 322 TMPFS_NODE_UNLOCK(nnode->tn_dir.tn_parent); 323 break; 324 325 case VFIFO: 326 /* FALLTHROUGH */ 327 case VSOCK: 328 break; 329 330 case VLNK: 331 MPASS(strlen(target) < MAXPATHLEN); 332 nnode->tn_size = strlen(target); 333 nnode->tn_link = malloc(nnode->tn_size, M_TMPFSNAME, 334 M_WAITOK); 335 memcpy(nnode->tn_link, target, nnode->tn_size); 336 break; 337 338 case VREG: 339 obj = nnode->tn_reg.tn_aobj = 340 vm_pager_allocate(OBJT_SWAP, NULL, 0, VM_PROT_DEFAULT, 0, 341 NULL /* XXXKIB - tmpfs needs swap reservation */); 342 VM_OBJECT_WLOCK(obj); 343 /* OBJ_TMPFS is set together with the setting of vp->v_object */ 344 vm_object_set_flag(obj, OBJ_NOSPLIT | OBJ_TMPFS_NODE); 345 vm_object_clear_flag(obj, OBJ_ONEMAPPING); 346 VM_OBJECT_WUNLOCK(obj); 347 break; 348 349 default: 350 panic("tmpfs_alloc_node: type %p %d", nnode, 351 (int)nnode->tn_type); 352 } 353 354 TMPFS_LOCK(tmp); 355 LIST_INSERT_HEAD(&tmp->tm_nodes_used, nnode, tn_entries); 356 nnode->tn_attached = true; 357 tmp->tm_nodes_inuse++; 358 tmp->tm_refcount++; 359 TMPFS_UNLOCK(tmp); 360 361 *node = nnode; 362 return (0); 363 } 364 365 /* 366 * Destroys the node pointed to by node from the file system 'tmp'. 367 * If the node references a directory, no entries are allowed. 368 */ 369 void 370 tmpfs_free_node(struct tmpfs_mount *tmp, struct tmpfs_node *node) 371 { 372 373 TMPFS_LOCK(tmp); 374 TMPFS_NODE_LOCK(node); 375 if (!tmpfs_free_node_locked(tmp, node, false)) { 376 TMPFS_NODE_UNLOCK(node); 377 TMPFS_UNLOCK(tmp); 378 } 379 } 380 381 bool 382 tmpfs_free_node_locked(struct tmpfs_mount *tmp, struct tmpfs_node *node, 383 bool detach) 384 { 385 vm_object_t uobj; 386 387 TMPFS_MP_ASSERT_LOCKED(tmp); 388 TMPFS_NODE_ASSERT_LOCKED(node); 389 KASSERT(node->tn_refcount > 0, ("node %p refcount zero", node)); 390 391 node->tn_refcount--; 392 if (node->tn_attached && (detach || node->tn_refcount == 0)) { 393 MPASS(tmp->tm_nodes_inuse > 0); 394 tmp->tm_nodes_inuse--; 395 LIST_REMOVE(node, tn_entries); 396 node->tn_attached = false; 397 } 398 if (node->tn_refcount > 0) 399 return (false); 400 401 #ifdef INVARIANTS 402 MPASS(node->tn_vnode == NULL); 403 MPASS((node->tn_vpstate & TMPFS_VNODE_ALLOCATING) == 0); 404 #endif 405 TMPFS_NODE_UNLOCK(node); 406 TMPFS_UNLOCK(tmp); 407 408 switch (node->tn_type) { 409 case VBLK: 410 /* FALLTHROUGH */ 411 case VCHR: 412 /* FALLTHROUGH */ 413 case VDIR: 414 /* FALLTHROUGH */ 415 case VFIFO: 416 /* FALLTHROUGH */ 417 case VSOCK: 418 break; 419 420 case VLNK: 421 free(node->tn_link, M_TMPFSNAME); 422 break; 423 424 case VREG: 425 uobj = node->tn_reg.tn_aobj; 426 if (uobj != NULL) { 427 if (uobj->size != 0) 428 atomic_subtract_long(&tmp->tm_pages_used, uobj->size); 429 KASSERT((uobj->flags & OBJ_TMPFS) == 0, 430 ("leaked OBJ_TMPFS node %p vm_obj %p", node, uobj)); 431 vm_object_deallocate(uobj); 432 } 433 break; 434 435 default: 436 panic("tmpfs_free_node: type %p %d", node, (int)node->tn_type); 437 } 438 439 uma_zfree(tmpfs_node_pool, node); 440 TMPFS_LOCK(tmp); 441 tmpfs_free_tmp(tmp); 442 return (true); 443 } 444 445 static __inline uint32_t 446 tmpfs_dirent_hash(const char *name, u_int len) 447 { 448 uint32_t hash; 449 450 hash = fnv_32_buf(name, len, FNV1_32_INIT + len) & TMPFS_DIRCOOKIE_MASK; 451 #ifdef TMPFS_DEBUG_DIRCOOKIE_DUP 452 hash &= 0xf; 453 #endif 454 if (hash < TMPFS_DIRCOOKIE_MIN) 455 hash += TMPFS_DIRCOOKIE_MIN; 456 457 return (hash); 458 } 459 460 static __inline off_t 461 tmpfs_dirent_cookie(struct tmpfs_dirent *de) 462 { 463 if (de == NULL) 464 return (TMPFS_DIRCOOKIE_EOF); 465 466 MPASS(de->td_cookie >= TMPFS_DIRCOOKIE_MIN); 467 468 return (de->td_cookie); 469 } 470 471 static __inline boolean_t 472 tmpfs_dirent_dup(struct tmpfs_dirent *de) 473 { 474 return ((de->td_cookie & TMPFS_DIRCOOKIE_DUP) != 0); 475 } 476 477 static __inline boolean_t 478 tmpfs_dirent_duphead(struct tmpfs_dirent *de) 479 { 480 return ((de->td_cookie & TMPFS_DIRCOOKIE_DUPHEAD) != 0); 481 } 482 483 void 484 tmpfs_dirent_init(struct tmpfs_dirent *de, const char *name, u_int namelen) 485 { 486 de->td_hash = de->td_cookie = tmpfs_dirent_hash(name, namelen); 487 memcpy(de->ud.td_name, name, namelen); 488 de->td_namelen = namelen; 489 } 490 491 /* 492 * Allocates a new directory entry for the node node with a name of name. 493 * The new directory entry is returned in *de. 494 * 495 * The link count of node is increased by one to reflect the new object 496 * referencing it. 497 * 498 * Returns zero on success or an appropriate error code on failure. 499 */ 500 int 501 tmpfs_alloc_dirent(struct tmpfs_mount *tmp, struct tmpfs_node *node, 502 const char *name, u_int len, struct tmpfs_dirent **de) 503 { 504 struct tmpfs_dirent *nde; 505 506 nde = uma_zalloc(tmpfs_dirent_pool, M_WAITOK); 507 nde->td_node = node; 508 if (name != NULL) { 509 nde->ud.td_name = malloc(len, M_TMPFSNAME, M_WAITOK); 510 tmpfs_dirent_init(nde, name, len); 511 } else 512 nde->td_namelen = 0; 513 if (node != NULL) 514 node->tn_links++; 515 516 *de = nde; 517 518 return (0); 519 } 520 521 /* 522 * Frees a directory entry. It is the caller's responsibility to destroy 523 * the node referenced by it if needed. 524 * 525 * The link count of node is decreased by one to reflect the removal of an 526 * object that referenced it. This only happens if 'node_exists' is true; 527 * otherwise the function will not access the node referred to by the 528 * directory entry, as it may already have been released from the outside. 529 */ 530 void 531 tmpfs_free_dirent(struct tmpfs_mount *tmp, struct tmpfs_dirent *de) 532 { 533 struct tmpfs_node *node; 534 535 node = de->td_node; 536 if (node != NULL) { 537 MPASS(node->tn_links > 0); 538 node->tn_links--; 539 } 540 if (!tmpfs_dirent_duphead(de) && de->ud.td_name != NULL) 541 free(de->ud.td_name, M_TMPFSNAME); 542 uma_zfree(tmpfs_dirent_pool, de); 543 } 544 545 void 546 tmpfs_destroy_vobject(struct vnode *vp, vm_object_t obj) 547 { 548 549 ASSERT_VOP_ELOCKED(vp, "tmpfs_destroy_vobject"); 550 if (vp->v_type != VREG || obj == NULL) 551 return; 552 553 VM_OBJECT_WLOCK(obj); 554 VI_LOCK(vp); 555 vm_object_clear_flag(obj, OBJ_TMPFS); 556 obj->un_pager.swp.swp_tmpfs = NULL; 557 if (vp->v_writecount < 0) 558 vp->v_writecount = 0; 559 VI_UNLOCK(vp); 560 VM_OBJECT_WUNLOCK(obj); 561 } 562 563 /* 564 * Need to clear v_object for insmntque failure. 565 */ 566 static void 567 tmpfs_insmntque_dtr(struct vnode *vp, void *dtr_arg) 568 { 569 570 tmpfs_destroy_vobject(vp, vp->v_object); 571 vp->v_object = NULL; 572 vp->v_data = NULL; 573 vp->v_op = &dead_vnodeops; 574 vgone(vp); 575 vput(vp); 576 } 577 578 /* 579 * Allocates a new vnode for the node node or returns a new reference to 580 * an existing one if the node had already a vnode referencing it. The 581 * resulting locked vnode is returned in *vpp. 582 * 583 * Returns zero on success or an appropriate error code on failure. 584 */ 585 int 586 tmpfs_alloc_vp(struct mount *mp, struct tmpfs_node *node, int lkflag, 587 struct vnode **vpp) 588 { 589 struct vnode *vp; 590 struct tmpfs_mount *tm; 591 vm_object_t object; 592 int error; 593 594 error = 0; 595 tm = VFS_TO_TMPFS(mp); 596 TMPFS_NODE_LOCK(node); 597 tmpfs_ref_node_locked(node); 598 loop: 599 TMPFS_NODE_ASSERT_LOCKED(node); 600 if ((vp = node->tn_vnode) != NULL) { 601 MPASS((node->tn_vpstate & TMPFS_VNODE_DOOMED) == 0); 602 VI_LOCK(vp); 603 if ((node->tn_type == VDIR && node->tn_dir.tn_parent == NULL) || 604 ((vp->v_iflag & VI_DOOMED) != 0 && 605 (lkflag & LK_NOWAIT) != 0)) { 606 VI_UNLOCK(vp); 607 TMPFS_NODE_UNLOCK(node); 608 error = ENOENT; 609 vp = NULL; 610 goto out; 611 } 612 if ((vp->v_iflag & VI_DOOMED) != 0) { 613 VI_UNLOCK(vp); 614 node->tn_vpstate |= TMPFS_VNODE_WRECLAIM; 615 while ((node->tn_vpstate & TMPFS_VNODE_WRECLAIM) != 0) { 616 msleep(&node->tn_vnode, TMPFS_NODE_MTX(node), 617 0, "tmpfsE", 0); 618 } 619 goto loop; 620 } 621 TMPFS_NODE_UNLOCK(node); 622 error = vget(vp, lkflag | LK_INTERLOCK, curthread); 623 if (error == ENOENT) { 624 TMPFS_NODE_LOCK(node); 625 goto loop; 626 } 627 if (error != 0) { 628 vp = NULL; 629 goto out; 630 } 631 632 /* 633 * Make sure the vnode is still there after 634 * getting the interlock to avoid racing a free. 635 */ 636 if (node->tn_vnode == NULL || node->tn_vnode != vp) { 637 vput(vp); 638 TMPFS_NODE_LOCK(node); 639 goto loop; 640 } 641 642 goto out; 643 } 644 645 if ((node->tn_vpstate & TMPFS_VNODE_DOOMED) || 646 (node->tn_type == VDIR && node->tn_dir.tn_parent == NULL)) { 647 TMPFS_NODE_UNLOCK(node); 648 error = ENOENT; 649 vp = NULL; 650 goto out; 651 } 652 653 /* 654 * otherwise lock the vp list while we call getnewvnode 655 * since that can block. 656 */ 657 if (node->tn_vpstate & TMPFS_VNODE_ALLOCATING) { 658 node->tn_vpstate |= TMPFS_VNODE_WANT; 659 error = msleep((caddr_t) &node->tn_vpstate, 660 TMPFS_NODE_MTX(node), 0, "tmpfs_alloc_vp", 0); 661 if (error != 0) 662 goto out; 663 goto loop; 664 } else 665 node->tn_vpstate |= TMPFS_VNODE_ALLOCATING; 666 667 TMPFS_NODE_UNLOCK(node); 668 669 /* Get a new vnode and associate it with our node. */ 670 error = getnewvnode("tmpfs", mp, VFS_TO_TMPFS(mp)->tm_nonc ? 671 &tmpfs_vnodeop_nonc_entries : &tmpfs_vnodeop_entries, &vp); 672 if (error != 0) 673 goto unlock; 674 MPASS(vp != NULL); 675 676 /* lkflag is ignored, the lock is exclusive */ 677 (void) vn_lock(vp, lkflag | LK_RETRY); 678 679 vp->v_data = node; 680 vp->v_type = node->tn_type; 681 682 /* Type-specific initialization. */ 683 switch (node->tn_type) { 684 case VBLK: 685 /* FALLTHROUGH */ 686 case VCHR: 687 /* FALLTHROUGH */ 688 case VLNK: 689 /* FALLTHROUGH */ 690 case VSOCK: 691 break; 692 case VFIFO: 693 vp->v_op = &tmpfs_fifoop_entries; 694 break; 695 case VREG: 696 object = node->tn_reg.tn_aobj; 697 VM_OBJECT_WLOCK(object); 698 VI_LOCK(vp); 699 KASSERT(vp->v_object == NULL, ("Not NULL v_object in tmpfs")); 700 vp->v_object = object; 701 object->un_pager.swp.swp_tmpfs = vp; 702 vm_object_set_flag(object, OBJ_TMPFS); 703 VI_UNLOCK(vp); 704 VM_OBJECT_WUNLOCK(object); 705 break; 706 case VDIR: 707 MPASS(node->tn_dir.tn_parent != NULL); 708 if (node->tn_dir.tn_parent == node) 709 vp->v_vflag |= VV_ROOT; 710 break; 711 712 default: 713 panic("tmpfs_alloc_vp: type %p %d", node, (int)node->tn_type); 714 } 715 if (vp->v_type != VFIFO) 716 VN_LOCK_ASHARE(vp); 717 718 error = insmntque1(vp, mp, tmpfs_insmntque_dtr, NULL); 719 if (error != 0) 720 vp = NULL; 721 722 unlock: 723 TMPFS_NODE_LOCK(node); 724 725 MPASS(node->tn_vpstate & TMPFS_VNODE_ALLOCATING); 726 node->tn_vpstate &= ~TMPFS_VNODE_ALLOCATING; 727 node->tn_vnode = vp; 728 729 if (node->tn_vpstate & TMPFS_VNODE_WANT) { 730 node->tn_vpstate &= ~TMPFS_VNODE_WANT; 731 TMPFS_NODE_UNLOCK(node); 732 wakeup((caddr_t) &node->tn_vpstate); 733 } else 734 TMPFS_NODE_UNLOCK(node); 735 736 out: 737 if (error == 0) { 738 *vpp = vp; 739 740 #ifdef INVARIANTS 741 MPASS(*vpp != NULL && VOP_ISLOCKED(*vpp)); 742 TMPFS_NODE_LOCK(node); 743 MPASS(*vpp == node->tn_vnode); 744 TMPFS_NODE_UNLOCK(node); 745 #endif 746 } 747 tmpfs_free_node(tm, node); 748 749 return (error); 750 } 751 752 /* 753 * Destroys the association between the vnode vp and the node it 754 * references. 755 */ 756 void 757 tmpfs_free_vp(struct vnode *vp) 758 { 759 struct tmpfs_node *node; 760 761 node = VP_TO_TMPFS_NODE(vp); 762 763 TMPFS_NODE_ASSERT_LOCKED(node); 764 node->tn_vnode = NULL; 765 if ((node->tn_vpstate & TMPFS_VNODE_WRECLAIM) != 0) 766 wakeup(&node->tn_vnode); 767 node->tn_vpstate &= ~TMPFS_VNODE_WRECLAIM; 768 vp->v_data = NULL; 769 } 770 771 /* 772 * Allocates a new file of type 'type' and adds it to the parent directory 773 * 'dvp'; this addition is done using the component name given in 'cnp'. 774 * The ownership of the new file is automatically assigned based on the 775 * credentials of the caller (through 'cnp'), the group is set based on 776 * the parent directory and the mode is determined from the 'vap' argument. 777 * If successful, *vpp holds a vnode to the newly created file and zero 778 * is returned. Otherwise *vpp is NULL and the function returns an 779 * appropriate error code. 780 */ 781 int 782 tmpfs_alloc_file(struct vnode *dvp, struct vnode **vpp, struct vattr *vap, 783 struct componentname *cnp, char *target) 784 { 785 int error; 786 struct tmpfs_dirent *de; 787 struct tmpfs_mount *tmp; 788 struct tmpfs_node *dnode; 789 struct tmpfs_node *node; 790 struct tmpfs_node *parent; 791 792 ASSERT_VOP_ELOCKED(dvp, "tmpfs_alloc_file"); 793 MPASS(cnp->cn_flags & HASBUF); 794 795 tmp = VFS_TO_TMPFS(dvp->v_mount); 796 dnode = VP_TO_TMPFS_DIR(dvp); 797 *vpp = NULL; 798 799 /* If the entry we are creating is a directory, we cannot overflow 800 * the number of links of its parent, because it will get a new 801 * link. */ 802 if (vap->va_type == VDIR) { 803 /* Ensure that we do not overflow the maximum number of links 804 * imposed by the system. */ 805 MPASS(dnode->tn_links <= TMPFS_LINK_MAX); 806 if (dnode->tn_links == TMPFS_LINK_MAX) { 807 return (EMLINK); 808 } 809 810 parent = dnode; 811 MPASS(parent != NULL); 812 } else 813 parent = NULL; 814 815 /* Allocate a node that represents the new file. */ 816 error = tmpfs_alloc_node(dvp->v_mount, tmp, vap->va_type, 817 cnp->cn_cred->cr_uid, dnode->tn_gid, vap->va_mode, parent, 818 target, vap->va_rdev, &node); 819 if (error != 0) 820 return (error); 821 822 /* Allocate a directory entry that points to the new file. */ 823 error = tmpfs_alloc_dirent(tmp, node, cnp->cn_nameptr, cnp->cn_namelen, 824 &de); 825 if (error != 0) { 826 tmpfs_free_node(tmp, node); 827 return (error); 828 } 829 830 /* Allocate a vnode for the new file. */ 831 error = tmpfs_alloc_vp(dvp->v_mount, node, LK_EXCLUSIVE, vpp); 832 if (error != 0) { 833 tmpfs_free_dirent(tmp, de); 834 tmpfs_free_node(tmp, node); 835 return (error); 836 } 837 838 /* Now that all required items are allocated, we can proceed to 839 * insert the new node into the directory, an operation that 840 * cannot fail. */ 841 if (cnp->cn_flags & ISWHITEOUT) 842 tmpfs_dir_whiteout_remove(dvp, cnp); 843 tmpfs_dir_attach(dvp, de); 844 return (0); 845 } 846 847 struct tmpfs_dirent * 848 tmpfs_dir_first(struct tmpfs_node *dnode, struct tmpfs_dir_cursor *dc) 849 { 850 struct tmpfs_dirent *de; 851 852 de = RB_MIN(tmpfs_dir, &dnode->tn_dir.tn_dirhead); 853 dc->tdc_tree = de; 854 if (de != NULL && tmpfs_dirent_duphead(de)) 855 de = LIST_FIRST(&de->ud.td_duphead); 856 dc->tdc_current = de; 857 858 return (dc->tdc_current); 859 } 860 861 struct tmpfs_dirent * 862 tmpfs_dir_next(struct tmpfs_node *dnode, struct tmpfs_dir_cursor *dc) 863 { 864 struct tmpfs_dirent *de; 865 866 MPASS(dc->tdc_tree != NULL); 867 if (tmpfs_dirent_dup(dc->tdc_current)) { 868 dc->tdc_current = LIST_NEXT(dc->tdc_current, uh.td_dup.entries); 869 if (dc->tdc_current != NULL) 870 return (dc->tdc_current); 871 } 872 dc->tdc_tree = dc->tdc_current = RB_NEXT(tmpfs_dir, 873 &dnode->tn_dir.tn_dirhead, dc->tdc_tree); 874 if ((de = dc->tdc_current) != NULL && tmpfs_dirent_duphead(de)) { 875 dc->tdc_current = LIST_FIRST(&de->ud.td_duphead); 876 MPASS(dc->tdc_current != NULL); 877 } 878 879 return (dc->tdc_current); 880 } 881 882 /* Lookup directory entry in RB-Tree. Function may return duphead entry. */ 883 static struct tmpfs_dirent * 884 tmpfs_dir_xlookup_hash(struct tmpfs_node *dnode, uint32_t hash) 885 { 886 struct tmpfs_dirent *de, dekey; 887 888 dekey.td_hash = hash; 889 de = RB_FIND(tmpfs_dir, &dnode->tn_dir.tn_dirhead, &dekey); 890 return (de); 891 } 892 893 /* Lookup directory entry by cookie, initialize directory cursor accordingly. */ 894 static struct tmpfs_dirent * 895 tmpfs_dir_lookup_cookie(struct tmpfs_node *node, off_t cookie, 896 struct tmpfs_dir_cursor *dc) 897 { 898 struct tmpfs_dir *dirhead = &node->tn_dir.tn_dirhead; 899 struct tmpfs_dirent *de, dekey; 900 901 MPASS(cookie >= TMPFS_DIRCOOKIE_MIN); 902 903 if (cookie == node->tn_dir.tn_readdir_lastn && 904 (de = node->tn_dir.tn_readdir_lastp) != NULL) { 905 /* Protect against possible race, tn_readdir_last[pn] 906 * may be updated with only shared vnode lock held. */ 907 if (cookie == tmpfs_dirent_cookie(de)) 908 goto out; 909 } 910 911 if ((cookie & TMPFS_DIRCOOKIE_DUP) != 0) { 912 LIST_FOREACH(de, &node->tn_dir.tn_dupindex, 913 uh.td_dup.index_entries) { 914 MPASS(tmpfs_dirent_dup(de)); 915 if (de->td_cookie == cookie) 916 goto out; 917 /* dupindex list is sorted. */ 918 if (de->td_cookie < cookie) { 919 de = NULL; 920 goto out; 921 } 922 } 923 MPASS(de == NULL); 924 goto out; 925 } 926 927 if ((cookie & TMPFS_DIRCOOKIE_MASK) != cookie) { 928 de = NULL; 929 } else { 930 dekey.td_hash = cookie; 931 /* Recover if direntry for cookie was removed */ 932 de = RB_NFIND(tmpfs_dir, dirhead, &dekey); 933 } 934 dc->tdc_tree = de; 935 dc->tdc_current = de; 936 if (de != NULL && tmpfs_dirent_duphead(de)) { 937 dc->tdc_current = LIST_FIRST(&de->ud.td_duphead); 938 MPASS(dc->tdc_current != NULL); 939 } 940 return (dc->tdc_current); 941 942 out: 943 dc->tdc_tree = de; 944 dc->tdc_current = de; 945 if (de != NULL && tmpfs_dirent_dup(de)) 946 dc->tdc_tree = tmpfs_dir_xlookup_hash(node, 947 de->td_hash); 948 return (dc->tdc_current); 949 } 950 951 /* 952 * Looks for a directory entry in the directory represented by node. 953 * 'cnp' describes the name of the entry to look for. Note that the . 954 * and .. components are not allowed as they do not physically exist 955 * within directories. 956 * 957 * Returns a pointer to the entry when found, otherwise NULL. 958 */ 959 struct tmpfs_dirent * 960 tmpfs_dir_lookup(struct tmpfs_node *node, struct tmpfs_node *f, 961 struct componentname *cnp) 962 { 963 struct tmpfs_dir_duphead *duphead; 964 struct tmpfs_dirent *de; 965 uint32_t hash; 966 967 MPASS(IMPLIES(cnp->cn_namelen == 1, cnp->cn_nameptr[0] != '.')); 968 MPASS(IMPLIES(cnp->cn_namelen == 2, !(cnp->cn_nameptr[0] == '.' && 969 cnp->cn_nameptr[1] == '.'))); 970 TMPFS_VALIDATE_DIR(node); 971 972 hash = tmpfs_dirent_hash(cnp->cn_nameptr, cnp->cn_namelen); 973 de = tmpfs_dir_xlookup_hash(node, hash); 974 if (de != NULL && tmpfs_dirent_duphead(de)) { 975 duphead = &de->ud.td_duphead; 976 LIST_FOREACH(de, duphead, uh.td_dup.entries) { 977 if (TMPFS_DIRENT_MATCHES(de, cnp->cn_nameptr, 978 cnp->cn_namelen)) 979 break; 980 } 981 } else if (de != NULL) { 982 if (!TMPFS_DIRENT_MATCHES(de, cnp->cn_nameptr, 983 cnp->cn_namelen)) 984 de = NULL; 985 } 986 if (de != NULL && f != NULL && de->td_node != f) 987 de = NULL; 988 989 return (de); 990 } 991 992 /* 993 * Attach duplicate-cookie directory entry nde to dnode and insert to dupindex 994 * list, allocate new cookie value. 995 */ 996 static void 997 tmpfs_dir_attach_dup(struct tmpfs_node *dnode, 998 struct tmpfs_dir_duphead *duphead, struct tmpfs_dirent *nde) 999 { 1000 struct tmpfs_dir_duphead *dupindex; 1001 struct tmpfs_dirent *de, *pde; 1002 1003 dupindex = &dnode->tn_dir.tn_dupindex; 1004 de = LIST_FIRST(dupindex); 1005 if (de == NULL || de->td_cookie < TMPFS_DIRCOOKIE_DUP_MAX) { 1006 if (de == NULL) 1007 nde->td_cookie = TMPFS_DIRCOOKIE_DUP_MIN; 1008 else 1009 nde->td_cookie = de->td_cookie + 1; 1010 MPASS(tmpfs_dirent_dup(nde)); 1011 LIST_INSERT_HEAD(dupindex, nde, uh.td_dup.index_entries); 1012 LIST_INSERT_HEAD(duphead, nde, uh.td_dup.entries); 1013 return; 1014 } 1015 1016 /* 1017 * Cookie numbers are near exhaustion. Scan dupindex list for unused 1018 * numbers. dupindex list is sorted in descending order. Keep it so 1019 * after inserting nde. 1020 */ 1021 while (1) { 1022 pde = de; 1023 de = LIST_NEXT(de, uh.td_dup.index_entries); 1024 if (de == NULL && pde->td_cookie != TMPFS_DIRCOOKIE_DUP_MIN) { 1025 /* 1026 * Last element of the index doesn't have minimal cookie 1027 * value, use it. 1028 */ 1029 nde->td_cookie = TMPFS_DIRCOOKIE_DUP_MIN; 1030 LIST_INSERT_AFTER(pde, nde, uh.td_dup.index_entries); 1031 LIST_INSERT_HEAD(duphead, nde, uh.td_dup.entries); 1032 return; 1033 } else if (de == NULL) { 1034 /* 1035 * We are so lucky have 2^30 hash duplicates in single 1036 * directory :) Return largest possible cookie value. 1037 * It should be fine except possible issues with 1038 * VOP_READDIR restart. 1039 */ 1040 nde->td_cookie = TMPFS_DIRCOOKIE_DUP_MAX; 1041 LIST_INSERT_HEAD(dupindex, nde, 1042 uh.td_dup.index_entries); 1043 LIST_INSERT_HEAD(duphead, nde, uh.td_dup.entries); 1044 return; 1045 } 1046 if (de->td_cookie + 1 == pde->td_cookie || 1047 de->td_cookie >= TMPFS_DIRCOOKIE_DUP_MAX) 1048 continue; /* No hole or invalid cookie. */ 1049 nde->td_cookie = de->td_cookie + 1; 1050 MPASS(tmpfs_dirent_dup(nde)); 1051 MPASS(pde->td_cookie > nde->td_cookie); 1052 MPASS(nde->td_cookie > de->td_cookie); 1053 LIST_INSERT_BEFORE(de, nde, uh.td_dup.index_entries); 1054 LIST_INSERT_HEAD(duphead, nde, uh.td_dup.entries); 1055 return; 1056 } 1057 } 1058 1059 /* 1060 * Attaches the directory entry de to the directory represented by vp. 1061 * Note that this does not change the link count of the node pointed by 1062 * the directory entry, as this is done by tmpfs_alloc_dirent. 1063 */ 1064 void 1065 tmpfs_dir_attach(struct vnode *vp, struct tmpfs_dirent *de) 1066 { 1067 struct tmpfs_node *dnode; 1068 struct tmpfs_dirent *xde, *nde; 1069 1070 ASSERT_VOP_ELOCKED(vp, __func__); 1071 MPASS(de->td_namelen > 0); 1072 MPASS(de->td_hash >= TMPFS_DIRCOOKIE_MIN); 1073 MPASS(de->td_cookie == de->td_hash); 1074 1075 dnode = VP_TO_TMPFS_DIR(vp); 1076 dnode->tn_dir.tn_readdir_lastn = 0; 1077 dnode->tn_dir.tn_readdir_lastp = NULL; 1078 1079 MPASS(!tmpfs_dirent_dup(de)); 1080 xde = RB_INSERT(tmpfs_dir, &dnode->tn_dir.tn_dirhead, de); 1081 if (xde != NULL && tmpfs_dirent_duphead(xde)) 1082 tmpfs_dir_attach_dup(dnode, &xde->ud.td_duphead, de); 1083 else if (xde != NULL) { 1084 /* 1085 * Allocate new duphead. Swap xde with duphead to avoid 1086 * adding/removing elements with the same hash. 1087 */ 1088 MPASS(!tmpfs_dirent_dup(xde)); 1089 tmpfs_alloc_dirent(VFS_TO_TMPFS(vp->v_mount), NULL, NULL, 0, 1090 &nde); 1091 /* *nde = *xde; XXX gcc 4.2.1 may generate invalid code. */ 1092 memcpy(nde, xde, sizeof(*xde)); 1093 xde->td_cookie |= TMPFS_DIRCOOKIE_DUPHEAD; 1094 LIST_INIT(&xde->ud.td_duphead); 1095 xde->td_namelen = 0; 1096 xde->td_node = NULL; 1097 tmpfs_dir_attach_dup(dnode, &xde->ud.td_duphead, nde); 1098 tmpfs_dir_attach_dup(dnode, &xde->ud.td_duphead, de); 1099 } 1100 dnode->tn_size += sizeof(struct tmpfs_dirent); 1101 dnode->tn_status |= TMPFS_NODE_ACCESSED | TMPFS_NODE_CHANGED | \ 1102 TMPFS_NODE_MODIFIED; 1103 tmpfs_update(vp); 1104 } 1105 1106 /* 1107 * Detaches the directory entry de from the directory represented by vp. 1108 * Note that this does not change the link count of the node pointed by 1109 * the directory entry, as this is done by tmpfs_free_dirent. 1110 */ 1111 void 1112 tmpfs_dir_detach(struct vnode *vp, struct tmpfs_dirent *de) 1113 { 1114 struct tmpfs_mount *tmp; 1115 struct tmpfs_dir *head; 1116 struct tmpfs_node *dnode; 1117 struct tmpfs_dirent *xde; 1118 1119 ASSERT_VOP_ELOCKED(vp, __func__); 1120 1121 dnode = VP_TO_TMPFS_DIR(vp); 1122 head = &dnode->tn_dir.tn_dirhead; 1123 dnode->tn_dir.tn_readdir_lastn = 0; 1124 dnode->tn_dir.tn_readdir_lastp = NULL; 1125 1126 if (tmpfs_dirent_dup(de)) { 1127 /* Remove duphead if de was last entry. */ 1128 if (LIST_NEXT(de, uh.td_dup.entries) == NULL) { 1129 xde = tmpfs_dir_xlookup_hash(dnode, de->td_hash); 1130 MPASS(tmpfs_dirent_duphead(xde)); 1131 } else 1132 xde = NULL; 1133 LIST_REMOVE(de, uh.td_dup.entries); 1134 LIST_REMOVE(de, uh.td_dup.index_entries); 1135 if (xde != NULL) { 1136 if (LIST_EMPTY(&xde->ud.td_duphead)) { 1137 RB_REMOVE(tmpfs_dir, head, xde); 1138 tmp = VFS_TO_TMPFS(vp->v_mount); 1139 MPASS(xde->td_node == NULL); 1140 tmpfs_free_dirent(tmp, xde); 1141 } 1142 } 1143 de->td_cookie = de->td_hash; 1144 } else 1145 RB_REMOVE(tmpfs_dir, head, de); 1146 1147 dnode->tn_size -= sizeof(struct tmpfs_dirent); 1148 dnode->tn_status |= TMPFS_NODE_ACCESSED | TMPFS_NODE_CHANGED | \ 1149 TMPFS_NODE_MODIFIED; 1150 tmpfs_update(vp); 1151 } 1152 1153 void 1154 tmpfs_dir_destroy(struct tmpfs_mount *tmp, struct tmpfs_node *dnode) 1155 { 1156 struct tmpfs_dirent *de, *dde, *nde; 1157 1158 RB_FOREACH_SAFE(de, tmpfs_dir, &dnode->tn_dir.tn_dirhead, nde) { 1159 RB_REMOVE(tmpfs_dir, &dnode->tn_dir.tn_dirhead, de); 1160 /* Node may already be destroyed. */ 1161 de->td_node = NULL; 1162 if (tmpfs_dirent_duphead(de)) { 1163 while ((dde = LIST_FIRST(&de->ud.td_duphead)) != NULL) { 1164 LIST_REMOVE(dde, uh.td_dup.entries); 1165 dde->td_node = NULL; 1166 tmpfs_free_dirent(tmp, dde); 1167 } 1168 } 1169 tmpfs_free_dirent(tmp, de); 1170 } 1171 } 1172 1173 /* 1174 * Helper function for tmpfs_readdir. Creates a '.' entry for the given 1175 * directory and returns it in the uio space. The function returns 0 1176 * on success, -1 if there was not enough space in the uio structure to 1177 * hold the directory entry or an appropriate error code if another 1178 * error happens. 1179 */ 1180 static int 1181 tmpfs_dir_getdotdent(struct tmpfs_mount *tm, struct tmpfs_node *node, 1182 struct uio *uio) 1183 { 1184 int error; 1185 struct dirent dent; 1186 1187 TMPFS_VALIDATE_DIR(node); 1188 MPASS(uio->uio_offset == TMPFS_DIRCOOKIE_DOT); 1189 1190 dent.d_fileno = node->tn_id; 1191 dent.d_off = TMPFS_DIRCOOKIE_DOTDOT; 1192 dent.d_type = DT_DIR; 1193 dent.d_namlen = 1; 1194 dent.d_name[0] = '.'; 1195 dent.d_reclen = GENERIC_DIRSIZ(&dent); 1196 dirent_terminate(&dent); 1197 1198 if (dent.d_reclen > uio->uio_resid) 1199 error = EJUSTRETURN; 1200 else 1201 error = uiomove(&dent, dent.d_reclen, uio); 1202 1203 tmpfs_set_status(tm, node, TMPFS_NODE_ACCESSED); 1204 1205 return (error); 1206 } 1207 1208 /* 1209 * Helper function for tmpfs_readdir. Creates a '..' entry for the given 1210 * directory and returns it in the uio space. The function returns 0 1211 * on success, -1 if there was not enough space in the uio structure to 1212 * hold the directory entry or an appropriate error code if another 1213 * error happens. 1214 */ 1215 static int 1216 tmpfs_dir_getdotdotdent(struct tmpfs_mount *tm, struct tmpfs_node *node, 1217 struct uio *uio, off_t next) 1218 { 1219 struct tmpfs_node *parent; 1220 struct dirent dent; 1221 int error; 1222 1223 TMPFS_VALIDATE_DIR(node); 1224 MPASS(uio->uio_offset == TMPFS_DIRCOOKIE_DOTDOT); 1225 1226 /* 1227 * Return ENOENT if the current node is already removed. 1228 */ 1229 TMPFS_ASSERT_LOCKED(node); 1230 parent = node->tn_dir.tn_parent; 1231 if (parent == NULL) 1232 return (ENOENT); 1233 1234 TMPFS_NODE_LOCK(parent); 1235 dent.d_fileno = parent->tn_id; 1236 TMPFS_NODE_UNLOCK(parent); 1237 1238 dent.d_off = next; 1239 dent.d_type = DT_DIR; 1240 dent.d_namlen = 2; 1241 dent.d_name[0] = '.'; 1242 dent.d_name[1] = '.'; 1243 dent.d_reclen = GENERIC_DIRSIZ(&dent); 1244 dirent_terminate(&dent); 1245 1246 if (dent.d_reclen > uio->uio_resid) 1247 error = EJUSTRETURN; 1248 else 1249 error = uiomove(&dent, dent.d_reclen, uio); 1250 1251 tmpfs_set_status(tm, node, TMPFS_NODE_ACCESSED); 1252 1253 return (error); 1254 } 1255 1256 /* 1257 * Helper function for tmpfs_readdir. Returns as much directory entries 1258 * as can fit in the uio space. The read starts at uio->uio_offset. 1259 * The function returns 0 on success, -1 if there was not enough space 1260 * in the uio structure to hold the directory entry or an appropriate 1261 * error code if another error happens. 1262 */ 1263 int 1264 tmpfs_dir_getdents(struct tmpfs_mount *tm, struct tmpfs_node *node, 1265 struct uio *uio, int maxcookies, u_long *cookies, int *ncookies) 1266 { 1267 struct tmpfs_dir_cursor dc; 1268 struct tmpfs_dirent *de, *nde; 1269 off_t off; 1270 int error; 1271 1272 TMPFS_VALIDATE_DIR(node); 1273 1274 off = 0; 1275 1276 /* 1277 * Lookup the node from the current offset. The starting offset of 1278 * 0 will lookup both '.' and '..', and then the first real entry, 1279 * or EOF if there are none. Then find all entries for the dir that 1280 * fit into the buffer. Once no more entries are found (de == NULL), 1281 * the offset is set to TMPFS_DIRCOOKIE_EOF, which will cause the next 1282 * call to return 0. 1283 */ 1284 switch (uio->uio_offset) { 1285 case TMPFS_DIRCOOKIE_DOT: 1286 error = tmpfs_dir_getdotdent(tm, node, uio); 1287 if (error != 0) 1288 return (error); 1289 uio->uio_offset = off = TMPFS_DIRCOOKIE_DOTDOT; 1290 if (cookies != NULL) 1291 cookies[(*ncookies)++] = off; 1292 /* FALLTHROUGH */ 1293 case TMPFS_DIRCOOKIE_DOTDOT: 1294 de = tmpfs_dir_first(node, &dc); 1295 off = tmpfs_dirent_cookie(de); 1296 error = tmpfs_dir_getdotdotdent(tm, node, uio, off); 1297 if (error != 0) 1298 return (error); 1299 uio->uio_offset = off; 1300 if (cookies != NULL) 1301 cookies[(*ncookies)++] = off; 1302 /* EOF. */ 1303 if (de == NULL) 1304 return (0); 1305 break; 1306 case TMPFS_DIRCOOKIE_EOF: 1307 return (0); 1308 default: 1309 de = tmpfs_dir_lookup_cookie(node, uio->uio_offset, &dc); 1310 if (de == NULL) 1311 return (EINVAL); 1312 if (cookies != NULL) 1313 off = tmpfs_dirent_cookie(de); 1314 } 1315 1316 /* 1317 * Read as much entries as possible; i.e., until we reach the end of the 1318 * directory or we exhaust uio space. 1319 */ 1320 do { 1321 struct dirent d; 1322 1323 /* 1324 * Create a dirent structure representing the current tmpfs_node 1325 * and fill it. 1326 */ 1327 if (de->td_node == NULL) { 1328 d.d_fileno = 1; 1329 d.d_type = DT_WHT; 1330 } else { 1331 d.d_fileno = de->td_node->tn_id; 1332 switch (de->td_node->tn_type) { 1333 case VBLK: 1334 d.d_type = DT_BLK; 1335 break; 1336 1337 case VCHR: 1338 d.d_type = DT_CHR; 1339 break; 1340 1341 case VDIR: 1342 d.d_type = DT_DIR; 1343 break; 1344 1345 case VFIFO: 1346 d.d_type = DT_FIFO; 1347 break; 1348 1349 case VLNK: 1350 d.d_type = DT_LNK; 1351 break; 1352 1353 case VREG: 1354 d.d_type = DT_REG; 1355 break; 1356 1357 case VSOCK: 1358 d.d_type = DT_SOCK; 1359 break; 1360 1361 default: 1362 panic("tmpfs_dir_getdents: type %p %d", 1363 de->td_node, (int)de->td_node->tn_type); 1364 } 1365 } 1366 d.d_namlen = de->td_namelen; 1367 MPASS(de->td_namelen < sizeof(d.d_name)); 1368 (void)memcpy(d.d_name, de->ud.td_name, de->td_namelen); 1369 d.d_reclen = GENERIC_DIRSIZ(&d); 1370 1371 /* 1372 * Stop reading if the directory entry we are treating is bigger 1373 * than the amount of data that can be returned. 1374 */ 1375 if (d.d_reclen > uio->uio_resid) { 1376 error = EJUSTRETURN; 1377 break; 1378 } 1379 1380 nde = tmpfs_dir_next(node, &dc); 1381 d.d_off = tmpfs_dirent_cookie(nde); 1382 dirent_terminate(&d); 1383 1384 /* 1385 * Copy the new dirent structure into the output buffer and 1386 * advance pointers. 1387 */ 1388 error = uiomove(&d, d.d_reclen, uio); 1389 if (error == 0) { 1390 de = nde; 1391 if (cookies != NULL) { 1392 off = tmpfs_dirent_cookie(de); 1393 MPASS(*ncookies < maxcookies); 1394 cookies[(*ncookies)++] = off; 1395 } 1396 } 1397 } while (error == 0 && uio->uio_resid > 0 && de != NULL); 1398 1399 /* Skip setting off when using cookies as it is already done above. */ 1400 if (cookies == NULL) 1401 off = tmpfs_dirent_cookie(de); 1402 1403 /* Update the offset and cache. */ 1404 uio->uio_offset = off; 1405 node->tn_dir.tn_readdir_lastn = off; 1406 node->tn_dir.tn_readdir_lastp = de; 1407 1408 tmpfs_set_status(tm, node, TMPFS_NODE_ACCESSED); 1409 return error; 1410 } 1411 1412 int 1413 tmpfs_dir_whiteout_add(struct vnode *dvp, struct componentname *cnp) 1414 { 1415 struct tmpfs_dirent *de; 1416 int error; 1417 1418 error = tmpfs_alloc_dirent(VFS_TO_TMPFS(dvp->v_mount), NULL, 1419 cnp->cn_nameptr, cnp->cn_namelen, &de); 1420 if (error != 0) 1421 return (error); 1422 tmpfs_dir_attach(dvp, de); 1423 return (0); 1424 } 1425 1426 void 1427 tmpfs_dir_whiteout_remove(struct vnode *dvp, struct componentname *cnp) 1428 { 1429 struct tmpfs_dirent *de; 1430 1431 de = tmpfs_dir_lookup(VP_TO_TMPFS_DIR(dvp), NULL, cnp); 1432 MPASS(de != NULL && de->td_node == NULL); 1433 tmpfs_dir_detach(dvp, de); 1434 tmpfs_free_dirent(VFS_TO_TMPFS(dvp->v_mount), de); 1435 } 1436 1437 /* 1438 * Resizes the aobj associated with the regular file pointed to by 'vp' to the 1439 * size 'newsize'. 'vp' must point to a vnode that represents a regular file. 1440 * 'newsize' must be positive. 1441 * 1442 * Returns zero on success or an appropriate error code on failure. 1443 */ 1444 int 1445 tmpfs_reg_resize(struct vnode *vp, off_t newsize, boolean_t ignerr) 1446 { 1447 struct tmpfs_mount *tmp; 1448 struct tmpfs_node *node; 1449 vm_object_t uobj; 1450 vm_page_t m; 1451 vm_pindex_t idx, newpages, oldpages; 1452 off_t oldsize; 1453 int base, rv; 1454 1455 MPASS(vp->v_type == VREG); 1456 MPASS(newsize >= 0); 1457 1458 node = VP_TO_TMPFS_NODE(vp); 1459 uobj = node->tn_reg.tn_aobj; 1460 tmp = VFS_TO_TMPFS(vp->v_mount); 1461 1462 /* 1463 * Convert the old and new sizes to the number of pages needed to 1464 * store them. It may happen that we do not need to do anything 1465 * because the last allocated page can accommodate the change on 1466 * its own. 1467 */ 1468 oldsize = node->tn_size; 1469 oldpages = OFF_TO_IDX(oldsize + PAGE_MASK); 1470 MPASS(oldpages == uobj->size); 1471 newpages = OFF_TO_IDX(newsize + PAGE_MASK); 1472 1473 if (__predict_true(newpages == oldpages && newsize >= oldsize)) { 1474 node->tn_size = newsize; 1475 return (0); 1476 } 1477 1478 if (newpages > oldpages && 1479 tmpfs_pages_check_avail(tmp, newpages - oldpages) == 0) 1480 return (ENOSPC); 1481 1482 VM_OBJECT_WLOCK(uobj); 1483 if (newsize < oldsize) { 1484 /* 1485 * Zero the truncated part of the last page. 1486 */ 1487 base = newsize & PAGE_MASK; 1488 if (base != 0) { 1489 idx = OFF_TO_IDX(newsize); 1490 retry: 1491 m = vm_page_lookup(uobj, idx); 1492 if (m != NULL) { 1493 if (vm_page_sleep_if_busy(m, "tmfssz")) 1494 goto retry; 1495 MPASS(m->valid == VM_PAGE_BITS_ALL); 1496 } else if (vm_pager_has_page(uobj, idx, NULL, NULL)) { 1497 m = vm_page_alloc(uobj, idx, VM_ALLOC_NORMAL | 1498 VM_ALLOC_WAITFAIL); 1499 if (m == NULL) 1500 goto retry; 1501 rv = vm_pager_get_pages(uobj, &m, 1, NULL, 1502 NULL); 1503 vm_page_lock(m); 1504 if (rv == VM_PAGER_OK) { 1505 /* 1506 * Since the page was not resident, 1507 * and therefore not recently 1508 * accessed, immediately enqueue it 1509 * for asynchronous laundering. The 1510 * current operation is not regarded 1511 * as an access. 1512 */ 1513 vm_page_launder(m); 1514 vm_page_unlock(m); 1515 vm_page_xunbusy(m); 1516 } else { 1517 vm_page_free(m); 1518 vm_page_unlock(m); 1519 if (ignerr) 1520 m = NULL; 1521 else { 1522 VM_OBJECT_WUNLOCK(uobj); 1523 return (EIO); 1524 } 1525 } 1526 } 1527 if (m != NULL) { 1528 pmap_zero_page_area(m, base, PAGE_SIZE - base); 1529 vm_page_dirty(m); 1530 vm_pager_page_unswapped(m); 1531 } 1532 } 1533 1534 /* 1535 * Release any swap space and free any whole pages. 1536 */ 1537 if (newpages < oldpages) { 1538 swap_pager_freespace(uobj, newpages, oldpages - 1539 newpages); 1540 vm_object_page_remove(uobj, newpages, 0, 0); 1541 } 1542 } 1543 uobj->size = newpages; 1544 VM_OBJECT_WUNLOCK(uobj); 1545 1546 atomic_add_long(&tmp->tm_pages_used, newpages - oldpages); 1547 1548 node->tn_size = newsize; 1549 return (0); 1550 } 1551 1552 void 1553 tmpfs_check_mtime(struct vnode *vp) 1554 { 1555 struct tmpfs_node *node; 1556 struct vm_object *obj; 1557 1558 ASSERT_VOP_ELOCKED(vp, "check_mtime"); 1559 if (vp->v_type != VREG) 1560 return; 1561 obj = vp->v_object; 1562 KASSERT((obj->flags & (OBJ_TMPFS_NODE | OBJ_TMPFS)) == 1563 (OBJ_TMPFS_NODE | OBJ_TMPFS), ("non-tmpfs obj")); 1564 /* unlocked read */ 1565 if ((obj->flags & OBJ_TMPFS_DIRTY) != 0) { 1566 VM_OBJECT_WLOCK(obj); 1567 if ((obj->flags & OBJ_TMPFS_DIRTY) != 0) { 1568 obj->flags &= ~OBJ_TMPFS_DIRTY; 1569 node = VP_TO_TMPFS_NODE(vp); 1570 node->tn_status |= TMPFS_NODE_MODIFIED | 1571 TMPFS_NODE_CHANGED; 1572 } 1573 VM_OBJECT_WUNLOCK(obj); 1574 } 1575 } 1576 1577 /* 1578 * Change flags of the given vnode. 1579 * Caller should execute tmpfs_update on vp after a successful execution. 1580 * The vnode must be locked on entry and remain locked on exit. 1581 */ 1582 int 1583 tmpfs_chflags(struct vnode *vp, u_long flags, struct ucred *cred, 1584 struct thread *p) 1585 { 1586 int error; 1587 struct tmpfs_node *node; 1588 1589 ASSERT_VOP_ELOCKED(vp, "chflags"); 1590 1591 node = VP_TO_TMPFS_NODE(vp); 1592 1593 if ((flags & ~(SF_APPEND | SF_ARCHIVED | SF_IMMUTABLE | SF_NOUNLINK | 1594 UF_APPEND | UF_ARCHIVE | UF_HIDDEN | UF_IMMUTABLE | UF_NODUMP | 1595 UF_NOUNLINK | UF_OFFLINE | UF_OPAQUE | UF_READONLY | UF_REPARSE | 1596 UF_SPARSE | UF_SYSTEM)) != 0) 1597 return (EOPNOTSUPP); 1598 1599 /* Disallow this operation if the file system is mounted read-only. */ 1600 if (vp->v_mount->mnt_flag & MNT_RDONLY) 1601 return (EROFS); 1602 1603 /* 1604 * Callers may only modify the file flags on objects they 1605 * have VADMIN rights for. 1606 */ 1607 if ((error = VOP_ACCESS(vp, VADMIN, cred, p))) 1608 return (error); 1609 /* 1610 * Unprivileged processes are not permitted to unset system 1611 * flags, or modify flags if any system flags are set. 1612 */ 1613 if (!priv_check_cred(cred, PRIV_VFS_SYSFLAGS, 0)) { 1614 if (node->tn_flags & 1615 (SF_NOUNLINK | SF_IMMUTABLE | SF_APPEND)) { 1616 error = securelevel_gt(cred, 0); 1617 if (error) 1618 return (error); 1619 } 1620 } else { 1621 if (node->tn_flags & 1622 (SF_NOUNLINK | SF_IMMUTABLE | SF_APPEND) || 1623 ((flags ^ node->tn_flags) & SF_SETTABLE)) 1624 return (EPERM); 1625 } 1626 node->tn_flags = flags; 1627 node->tn_status |= TMPFS_NODE_CHANGED; 1628 1629 ASSERT_VOP_ELOCKED(vp, "chflags2"); 1630 1631 return (0); 1632 } 1633 1634 /* 1635 * Change access mode on the given vnode. 1636 * Caller should execute tmpfs_update on vp after a successful execution. 1637 * The vnode must be locked on entry and remain locked on exit. 1638 */ 1639 int 1640 tmpfs_chmod(struct vnode *vp, mode_t mode, struct ucred *cred, struct thread *p) 1641 { 1642 int error; 1643 struct tmpfs_node *node; 1644 1645 ASSERT_VOP_ELOCKED(vp, "chmod"); 1646 1647 node = VP_TO_TMPFS_NODE(vp); 1648 1649 /* Disallow this operation if the file system is mounted read-only. */ 1650 if (vp->v_mount->mnt_flag & MNT_RDONLY) 1651 return (EROFS); 1652 1653 /* Immutable or append-only files cannot be modified, either. */ 1654 if (node->tn_flags & (IMMUTABLE | APPEND)) 1655 return (EPERM); 1656 1657 /* 1658 * To modify the permissions on a file, must possess VADMIN 1659 * for that file. 1660 */ 1661 if ((error = VOP_ACCESS(vp, VADMIN, cred, p))) 1662 return (error); 1663 1664 /* 1665 * Privileged processes may set the sticky bit on non-directories, 1666 * as well as set the setgid bit on a file with a group that the 1667 * process is not a member of. 1668 */ 1669 if (vp->v_type != VDIR && (mode & S_ISTXT)) { 1670 if (priv_check_cred(cred, PRIV_VFS_STICKYFILE, 0)) 1671 return (EFTYPE); 1672 } 1673 if (!groupmember(node->tn_gid, cred) && (mode & S_ISGID)) { 1674 error = priv_check_cred(cred, PRIV_VFS_SETGID, 0); 1675 if (error) 1676 return (error); 1677 } 1678 1679 1680 node->tn_mode &= ~ALLPERMS; 1681 node->tn_mode |= mode & ALLPERMS; 1682 1683 node->tn_status |= TMPFS_NODE_CHANGED; 1684 1685 ASSERT_VOP_ELOCKED(vp, "chmod2"); 1686 1687 return (0); 1688 } 1689 1690 /* 1691 * Change ownership of the given vnode. At least one of uid or gid must 1692 * be different than VNOVAL. If one is set to that value, the attribute 1693 * is unchanged. 1694 * Caller should execute tmpfs_update on vp after a successful execution. 1695 * The vnode must be locked on entry and remain locked on exit. 1696 */ 1697 int 1698 tmpfs_chown(struct vnode *vp, uid_t uid, gid_t gid, struct ucred *cred, 1699 struct thread *p) 1700 { 1701 int error; 1702 struct tmpfs_node *node; 1703 uid_t ouid; 1704 gid_t ogid; 1705 1706 ASSERT_VOP_ELOCKED(vp, "chown"); 1707 1708 node = VP_TO_TMPFS_NODE(vp); 1709 1710 /* Assign default values if they are unknown. */ 1711 MPASS(uid != VNOVAL || gid != VNOVAL); 1712 if (uid == VNOVAL) 1713 uid = node->tn_uid; 1714 if (gid == VNOVAL) 1715 gid = node->tn_gid; 1716 MPASS(uid != VNOVAL && gid != VNOVAL); 1717 1718 /* Disallow this operation if the file system is mounted read-only. */ 1719 if (vp->v_mount->mnt_flag & MNT_RDONLY) 1720 return (EROFS); 1721 1722 /* Immutable or append-only files cannot be modified, either. */ 1723 if (node->tn_flags & (IMMUTABLE | APPEND)) 1724 return (EPERM); 1725 1726 /* 1727 * To modify the ownership of a file, must possess VADMIN for that 1728 * file. 1729 */ 1730 if ((error = VOP_ACCESS(vp, VADMIN, cred, p))) 1731 return (error); 1732 1733 /* 1734 * To change the owner of a file, or change the group of a file to a 1735 * group of which we are not a member, the caller must have 1736 * privilege. 1737 */ 1738 if ((uid != node->tn_uid || 1739 (gid != node->tn_gid && !groupmember(gid, cred))) && 1740 (error = priv_check_cred(cred, PRIV_VFS_CHOWN, 0))) 1741 return (error); 1742 1743 ogid = node->tn_gid; 1744 ouid = node->tn_uid; 1745 1746 node->tn_uid = uid; 1747 node->tn_gid = gid; 1748 1749 node->tn_status |= TMPFS_NODE_CHANGED; 1750 1751 if ((node->tn_mode & (S_ISUID | S_ISGID)) && (ouid != uid || ogid != gid)) { 1752 if (priv_check_cred(cred, PRIV_VFS_RETAINSUGID, 0)) 1753 node->tn_mode &= ~(S_ISUID | S_ISGID); 1754 } 1755 1756 ASSERT_VOP_ELOCKED(vp, "chown2"); 1757 1758 return (0); 1759 } 1760 1761 /* 1762 * Change size of the given vnode. 1763 * Caller should execute tmpfs_update on vp after a successful execution. 1764 * The vnode must be locked on entry and remain locked on exit. 1765 */ 1766 int 1767 tmpfs_chsize(struct vnode *vp, u_quad_t size, struct ucred *cred, 1768 struct thread *p) 1769 { 1770 int error; 1771 struct tmpfs_node *node; 1772 1773 ASSERT_VOP_ELOCKED(vp, "chsize"); 1774 1775 node = VP_TO_TMPFS_NODE(vp); 1776 1777 /* Decide whether this is a valid operation based on the file type. */ 1778 error = 0; 1779 switch (vp->v_type) { 1780 case VDIR: 1781 return (EISDIR); 1782 1783 case VREG: 1784 if (vp->v_mount->mnt_flag & MNT_RDONLY) 1785 return (EROFS); 1786 break; 1787 1788 case VBLK: 1789 /* FALLTHROUGH */ 1790 case VCHR: 1791 /* FALLTHROUGH */ 1792 case VFIFO: 1793 /* 1794 * Allow modifications of special files even if in the file 1795 * system is mounted read-only (we are not modifying the 1796 * files themselves, but the objects they represent). 1797 */ 1798 return (0); 1799 1800 default: 1801 /* Anything else is unsupported. */ 1802 return (EOPNOTSUPP); 1803 } 1804 1805 /* Immutable or append-only files cannot be modified, either. */ 1806 if (node->tn_flags & (IMMUTABLE | APPEND)) 1807 return (EPERM); 1808 1809 error = tmpfs_truncate(vp, size); 1810 /* 1811 * tmpfs_truncate will raise the NOTE_EXTEND and NOTE_ATTRIB kevents 1812 * for us, as will update tn_status; no need to do that here. 1813 */ 1814 1815 ASSERT_VOP_ELOCKED(vp, "chsize2"); 1816 1817 return (error); 1818 } 1819 1820 /* 1821 * Change access and modification times of the given vnode. 1822 * Caller should execute tmpfs_update on vp after a successful execution. 1823 * The vnode must be locked on entry and remain locked on exit. 1824 */ 1825 int 1826 tmpfs_chtimes(struct vnode *vp, struct vattr *vap, 1827 struct ucred *cred, struct thread *l) 1828 { 1829 int error; 1830 struct tmpfs_node *node; 1831 1832 ASSERT_VOP_ELOCKED(vp, "chtimes"); 1833 1834 node = VP_TO_TMPFS_NODE(vp); 1835 1836 /* Disallow this operation if the file system is mounted read-only. */ 1837 if (vp->v_mount->mnt_flag & MNT_RDONLY) 1838 return (EROFS); 1839 1840 /* Immutable or append-only files cannot be modified, either. */ 1841 if (node->tn_flags & (IMMUTABLE | APPEND)) 1842 return (EPERM); 1843 1844 error = vn_utimes_perm(vp, vap, cred, l); 1845 if (error != 0) 1846 return (error); 1847 1848 if (vap->va_atime.tv_sec != VNOVAL) 1849 node->tn_status |= TMPFS_NODE_ACCESSED; 1850 1851 if (vap->va_mtime.tv_sec != VNOVAL) 1852 node->tn_status |= TMPFS_NODE_MODIFIED; 1853 1854 if (vap->va_birthtime.tv_sec != VNOVAL) 1855 node->tn_status |= TMPFS_NODE_MODIFIED; 1856 1857 tmpfs_itimes(vp, &vap->va_atime, &vap->va_mtime); 1858 1859 if (vap->va_birthtime.tv_sec != VNOVAL) 1860 node->tn_birthtime = vap->va_birthtime; 1861 ASSERT_VOP_ELOCKED(vp, "chtimes2"); 1862 1863 return (0); 1864 } 1865 1866 void 1867 tmpfs_set_status(struct tmpfs_mount *tm, struct tmpfs_node *node, int status) 1868 { 1869 1870 if ((node->tn_status & status) == status || tm->tm_ronly) 1871 return; 1872 TMPFS_NODE_LOCK(node); 1873 node->tn_status |= status; 1874 TMPFS_NODE_UNLOCK(node); 1875 } 1876 1877 /* Sync timestamps */ 1878 void 1879 tmpfs_itimes(struct vnode *vp, const struct timespec *acc, 1880 const struct timespec *mod) 1881 { 1882 struct tmpfs_node *node; 1883 struct timespec now; 1884 1885 ASSERT_VOP_LOCKED(vp, "tmpfs_itimes"); 1886 node = VP_TO_TMPFS_NODE(vp); 1887 1888 if ((node->tn_status & (TMPFS_NODE_ACCESSED | TMPFS_NODE_MODIFIED | 1889 TMPFS_NODE_CHANGED)) == 0) 1890 return; 1891 1892 vfs_timestamp(&now); 1893 TMPFS_NODE_LOCK(node); 1894 if (node->tn_status & TMPFS_NODE_ACCESSED) { 1895 if (acc == NULL) 1896 acc = &now; 1897 node->tn_atime = *acc; 1898 } 1899 if (node->tn_status & TMPFS_NODE_MODIFIED) { 1900 if (mod == NULL) 1901 mod = &now; 1902 node->tn_mtime = *mod; 1903 } 1904 if (node->tn_status & TMPFS_NODE_CHANGED) 1905 node->tn_ctime = now; 1906 node->tn_status &= ~(TMPFS_NODE_ACCESSED | TMPFS_NODE_MODIFIED | 1907 TMPFS_NODE_CHANGED); 1908 TMPFS_NODE_UNLOCK(node); 1909 1910 /* XXX: FIX? The entropy here is desirable, but the harvesting may be expensive */ 1911 random_harvest_queue(node, sizeof(*node), RANDOM_FS_ATIME); 1912 } 1913 1914 void 1915 tmpfs_update(struct vnode *vp) 1916 { 1917 1918 tmpfs_itimes(vp, NULL, NULL); 1919 } 1920 1921 int 1922 tmpfs_truncate(struct vnode *vp, off_t length) 1923 { 1924 int error; 1925 struct tmpfs_node *node; 1926 1927 node = VP_TO_TMPFS_NODE(vp); 1928 1929 if (length < 0) { 1930 error = EINVAL; 1931 goto out; 1932 } 1933 1934 if (node->tn_size == length) { 1935 error = 0; 1936 goto out; 1937 } 1938 1939 if (length > VFS_TO_TMPFS(vp->v_mount)->tm_maxfilesize) 1940 return (EFBIG); 1941 1942 error = tmpfs_reg_resize(vp, length, FALSE); 1943 if (error == 0) 1944 node->tn_status |= TMPFS_NODE_CHANGED | TMPFS_NODE_MODIFIED; 1945 1946 out: 1947 tmpfs_update(vp); 1948 1949 return (error); 1950 } 1951 1952 static __inline int 1953 tmpfs_dirtree_cmp(struct tmpfs_dirent *a, struct tmpfs_dirent *b) 1954 { 1955 if (a->td_hash > b->td_hash) 1956 return (1); 1957 else if (a->td_hash < b->td_hash) 1958 return (-1); 1959 return (0); 1960 } 1961 1962 RB_GENERATE_STATIC(tmpfs_dir, tmpfs_dirent, uh.td_entries, tmpfs_dirtree_cmp);
Cache object: de28f05acd0d991f9653d9b92ae87b55
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