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