1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1992, 1993, 1994, 1995 Jan-Simon Pendry. 5 * Copyright (c) 1992, 1993, 1994, 1995 6 * The Regents of the University of California. 7 * Copyright (c) 2005, 2006, 2012 Masanori Ozawa <ozawa@ongs.co.jp>, ONGS Inc. 8 * Copyright (c) 2006, 2012 Daichi Goto <daichi@freebsd.org> 9 * All rights reserved. 10 * 11 * This code is derived from software contributed to Berkeley by 12 * Jan-Simon Pendry. 13 * 14 * Redistribution and use in source and binary forms, with or without 15 * modification, are permitted provided that the following conditions 16 * are met: 17 * 1. Redistributions of source code must retain the above copyright 18 * notice, this list of conditions and the following disclaimer. 19 * 2. Redistributions in binary form must reproduce the above copyright 20 * notice, this list of conditions and the following disclaimer in the 21 * documentation and/or other materials provided with the distribution. 22 * 3. Neither the name of the University nor the names of its contributors 23 * may be used to endorse or promote products derived from this software 24 * without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 * 38 */ 39 40 #include <sys/param.h> 41 #include <sys/systm.h> 42 #include <sys/conf.h> 43 #include <sys/kernel.h> 44 #include <sys/lock.h> 45 #include <sys/malloc.h> 46 #include <sys/mount.h> 47 #include <sys/mutex.h> 48 #include <sys/namei.h> 49 #include <sys/sysctl.h> 50 #include <sys/vnode.h> 51 #include <sys/kdb.h> 52 #include <sys/fcntl.h> 53 #include <sys/stat.h> 54 #include <sys/dirent.h> 55 #include <sys/proc.h> 56 #include <sys/bio.h> 57 #include <sys/buf.h> 58 59 #include <fs/unionfs/union.h> 60 61 #include <machine/atomic.h> 62 63 #include <vm/vm.h> 64 #include <vm/vm_extern.h> 65 #include <vm/vm_object.h> 66 #include <vm/vnode_pager.h> 67 68 #if 0 69 #define UNIONFS_INTERNAL_DEBUG(msg, args...) printf(msg, ## args) 70 #define UNIONFS_IDBG_RENAME 71 #else 72 #define UNIONFS_INTERNAL_DEBUG(msg, args...) 73 #endif 74 75 #define KASSERT_UNIONFS_VNODE(vp) \ 76 VNASSERT(((vp)->v_op == &unionfs_vnodeops), vp, \ 77 ("%s: non-unionfs vnode", __func__)) 78 79 static int 80 unionfs_lookup(struct vop_cachedlookup_args *ap) 81 { 82 struct unionfs_node *dunp; 83 struct vnode *dvp, *udvp, *ldvp, *vp, *uvp, *lvp, *dtmpvp; 84 struct vattr va; 85 struct componentname *cnp; 86 struct thread *td; 87 u_long nameiop; 88 u_long cnflags, cnflagsbk; 89 int iswhiteout; 90 int lockflag; 91 int error , uerror, lerror; 92 93 iswhiteout = 0; 94 lockflag = 0; 95 error = uerror = lerror = ENOENT; 96 cnp = ap->a_cnp; 97 nameiop = cnp->cn_nameiop; 98 cnflags = cnp->cn_flags; 99 dvp = ap->a_dvp; 100 dunp = VTOUNIONFS(dvp); 101 udvp = dunp->un_uppervp; 102 ldvp = dunp->un_lowervp; 103 vp = uvp = lvp = NULLVP; 104 td = curthread; 105 *(ap->a_vpp) = NULLVP; 106 107 UNIONFS_INTERNAL_DEBUG( 108 "unionfs_lookup: enter: nameiop=%ld, flags=%lx, path=%s\n", 109 nameiop, cnflags, cnp->cn_nameptr); 110 111 if (dvp->v_type != VDIR) 112 return (ENOTDIR); 113 114 /* 115 * If read-only and op is not LOOKUP, will return EROFS. 116 */ 117 if ((cnflags & ISLASTCN) && 118 (dvp->v_mount->mnt_flag & MNT_RDONLY) && 119 LOOKUP != nameiop) 120 return (EROFS); 121 122 /* 123 * lookup dotdot 124 */ 125 if (cnflags & ISDOTDOT) { 126 if (LOOKUP != nameiop && udvp == NULLVP) 127 return (EROFS); 128 129 if (udvp != NULLVP) { 130 dtmpvp = udvp; 131 if (ldvp != NULLVP) 132 VOP_UNLOCK(ldvp); 133 } 134 else 135 dtmpvp = ldvp; 136 137 error = VOP_LOOKUP(dtmpvp, &vp, cnp); 138 139 if (dtmpvp == udvp && ldvp != NULLVP) { 140 VOP_UNLOCK(udvp); 141 vn_lock(dvp, LK_EXCLUSIVE | LK_RETRY); 142 } 143 144 if (error == 0) { 145 /* 146 * Exchange lock and reference from vp to 147 * dunp->un_dvp. vp is upper/lower vnode, but it 148 * will need to return the unionfs vnode. 149 */ 150 if (nameiop == DELETE || nameiop == RENAME || 151 (cnp->cn_lkflags & LK_TYPE_MASK)) 152 VOP_UNLOCK(vp); 153 vrele(vp); 154 155 VOP_UNLOCK(dvp); 156 *(ap->a_vpp) = dunp->un_dvp; 157 vref(dunp->un_dvp); 158 159 if (nameiop == DELETE || nameiop == RENAME) 160 vn_lock(dunp->un_dvp, LK_EXCLUSIVE | LK_RETRY); 161 else if (cnp->cn_lkflags & LK_TYPE_MASK) 162 vn_lock(dunp->un_dvp, cnp->cn_lkflags | 163 LK_RETRY); 164 165 vn_lock(dvp, LK_EXCLUSIVE | LK_RETRY); 166 } else if (error == ENOENT && (cnflags & MAKEENTRY) != 0) 167 cache_enter(dvp, NULLVP, cnp); 168 169 goto unionfs_lookup_return; 170 } 171 172 /* 173 * lookup upper layer 174 */ 175 if (udvp != NULLVP) { 176 uerror = VOP_LOOKUP(udvp, &uvp, cnp); 177 178 if (uerror == 0) { 179 if (udvp == uvp) { /* is dot */ 180 vrele(uvp); 181 *(ap->a_vpp) = dvp; 182 vref(dvp); 183 184 error = uerror; 185 goto unionfs_lookup_return; 186 } 187 if (nameiop == DELETE || nameiop == RENAME || 188 (cnp->cn_lkflags & LK_TYPE_MASK)) 189 VOP_UNLOCK(uvp); 190 } 191 192 /* check whiteout */ 193 if (uerror == ENOENT || uerror == EJUSTRETURN) 194 if (cnp->cn_flags & ISWHITEOUT) 195 iswhiteout = 1; /* don't lookup lower */ 196 if (iswhiteout == 0 && ldvp != NULLVP) 197 if (!VOP_GETATTR(udvp, &va, cnp->cn_cred) && 198 (va.va_flags & OPAQUE)) 199 iswhiteout = 1; /* don't lookup lower */ 200 #if 0 201 UNIONFS_INTERNAL_DEBUG( 202 "unionfs_lookup: debug: whiteout=%d, path=%s\n", 203 iswhiteout, cnp->cn_nameptr); 204 #endif 205 } 206 207 /* 208 * lookup lower layer 209 */ 210 if (ldvp != NULLVP && !(cnflags & DOWHITEOUT) && iswhiteout == 0) { 211 /* always op is LOOKUP */ 212 cnp->cn_nameiop = LOOKUP; 213 cnflagsbk = cnp->cn_flags; 214 cnp->cn_flags = cnflags; 215 216 lerror = VOP_LOOKUP(ldvp, &lvp, cnp); 217 218 cnp->cn_nameiop = nameiop; 219 if (udvp != NULLVP && (uerror == 0 || uerror == EJUSTRETURN)) 220 cnp->cn_flags = cnflagsbk; 221 222 if (lerror == 0) { 223 if (ldvp == lvp) { /* is dot */ 224 if (uvp != NULLVP) 225 vrele(uvp); /* no need? */ 226 vrele(lvp); 227 *(ap->a_vpp) = dvp; 228 vref(dvp); 229 230 UNIONFS_INTERNAL_DEBUG( 231 "unionfs_lookup: leave (%d)\n", lerror); 232 233 return (lerror); 234 } 235 if (cnp->cn_lkflags & LK_TYPE_MASK) 236 VOP_UNLOCK(lvp); 237 } 238 } 239 240 /* 241 * check lookup result 242 */ 243 if (uvp == NULLVP && lvp == NULLVP) { 244 error = (udvp != NULLVP ? uerror : lerror); 245 goto unionfs_lookup_return; 246 } 247 248 /* 249 * check vnode type 250 */ 251 if (uvp != NULLVP && lvp != NULLVP && uvp->v_type != lvp->v_type) { 252 vrele(lvp); 253 lvp = NULLVP; 254 } 255 256 /* 257 * check shadow dir 258 */ 259 if (uerror != 0 && uerror != EJUSTRETURN && udvp != NULLVP && 260 lerror == 0 && lvp != NULLVP && lvp->v_type == VDIR && 261 !(dvp->v_mount->mnt_flag & MNT_RDONLY) && 262 (1 < cnp->cn_namelen || '.' != *(cnp->cn_nameptr))) { 263 /* get unionfs vnode in order to create a new shadow dir. */ 264 error = unionfs_nodeget(dvp->v_mount, NULLVP, lvp, dvp, &vp, 265 cnp); 266 if (error != 0) 267 goto unionfs_lookup_cleanup; 268 269 if (LK_SHARED == (cnp->cn_lkflags & LK_TYPE_MASK)) 270 VOP_UNLOCK(vp); 271 if (LK_EXCLUSIVE != VOP_ISLOCKED(vp)) { 272 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 273 lockflag = 1; 274 } 275 error = unionfs_mkshadowdir(MOUNTTOUNIONFSMOUNT(dvp->v_mount), 276 udvp, VTOUNIONFS(vp), cnp, td); 277 if (lockflag != 0) 278 VOP_UNLOCK(vp); 279 if (error != 0) { 280 UNIONFSDEBUG( 281 "unionfs_lookup: Unable to create shadow dir."); 282 if ((cnp->cn_lkflags & LK_TYPE_MASK) == LK_EXCLUSIVE) 283 vput(vp); 284 else 285 vrele(vp); 286 goto unionfs_lookup_cleanup; 287 } 288 if ((cnp->cn_lkflags & LK_TYPE_MASK) == LK_SHARED) 289 vn_lock(vp, LK_SHARED | LK_RETRY); 290 } 291 /* 292 * get unionfs vnode. 293 */ 294 else { 295 if (uvp != NULLVP) 296 error = uerror; 297 else 298 error = lerror; 299 if (error != 0) 300 goto unionfs_lookup_cleanup; 301 /* 302 * get socket vnode. 303 */ 304 if (uvp != NULLVP && uvp->v_type == VSOCK) { 305 vp = uvp; 306 vref(vp); 307 if (cnp->cn_lkflags & LK_TYPE_MASK) 308 vn_lock(vp, cnp->cn_lkflags | LK_RETRY); 309 } 310 else if (lvp != NULLVP && lvp->v_type == VSOCK) { 311 vp = lvp; 312 vref(vp); 313 if (cnp->cn_lkflags & LK_TYPE_MASK) 314 vn_lock(vp, cnp->cn_lkflags | LK_RETRY); 315 } 316 /* 317 * get unionfs vnode. 318 */ 319 else 320 error = unionfs_nodeget(dvp->v_mount, uvp, lvp, 321 dvp, &vp, cnp); 322 if (error != 0) { 323 UNIONFSDEBUG( 324 "unionfs_lookup: Unable to create unionfs vnode."); 325 goto unionfs_lookup_cleanup; 326 } 327 if ((nameiop == DELETE || nameiop == RENAME) && 328 (cnp->cn_lkflags & LK_TYPE_MASK) == 0) 329 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 330 } 331 332 *(ap->a_vpp) = vp; 333 334 if ((cnflags & MAKEENTRY) && vp->v_type != VSOCK) 335 cache_enter(dvp, vp, cnp); 336 337 unionfs_lookup_cleanup: 338 if (uvp != NULLVP) 339 vrele(uvp); 340 if (lvp != NULLVP) 341 vrele(lvp); 342 343 if (error == ENOENT && (cnflags & MAKEENTRY) != 0) 344 cache_enter(dvp, NULLVP, cnp); 345 346 unionfs_lookup_return: 347 348 UNIONFS_INTERNAL_DEBUG("unionfs_lookup: leave (%d)\n", error); 349 350 return (error); 351 } 352 353 static int 354 unionfs_create(struct vop_create_args *ap) 355 { 356 struct unionfs_node *dunp; 357 struct componentname *cnp; 358 struct vnode *udvp; 359 struct vnode *vp; 360 int error; 361 362 UNIONFS_INTERNAL_DEBUG("unionfs_create: enter\n"); 363 364 KASSERT_UNIONFS_VNODE(ap->a_dvp); 365 366 dunp = VTOUNIONFS(ap->a_dvp); 367 cnp = ap->a_cnp; 368 udvp = dunp->un_uppervp; 369 error = EROFS; 370 371 if (udvp != NULLVP) { 372 error = VOP_CREATE(udvp, &vp, cnp, ap->a_vap); 373 if (error != 0) 374 goto unionfs_create_abort; 375 376 if (vp->v_type == VSOCK) 377 *(ap->a_vpp) = vp; 378 else { 379 VOP_UNLOCK(vp); 380 error = unionfs_nodeget(ap->a_dvp->v_mount, vp, NULLVP, 381 ap->a_dvp, ap->a_vpp, cnp); 382 vrele(vp); 383 } 384 } 385 386 unionfs_create_abort: 387 UNIONFS_INTERNAL_DEBUG("unionfs_create: leave (%d)\n", error); 388 389 return (error); 390 } 391 392 static int 393 unionfs_whiteout(struct vop_whiteout_args *ap) 394 { 395 struct unionfs_node *dunp; 396 struct componentname *cnp; 397 struct vnode *udvp; 398 int error; 399 400 UNIONFS_INTERNAL_DEBUG("unionfs_whiteout: enter\n"); 401 402 KASSERT_UNIONFS_VNODE(ap->a_dvp); 403 404 dunp = VTOUNIONFS(ap->a_dvp); 405 cnp = ap->a_cnp; 406 udvp = dunp->un_uppervp; 407 error = EOPNOTSUPP; 408 409 if (udvp != NULLVP) { 410 switch (ap->a_flags) { 411 case CREATE: 412 case DELETE: 413 case LOOKUP: 414 error = VOP_WHITEOUT(udvp, cnp, ap->a_flags); 415 break; 416 default: 417 error = EINVAL; 418 break; 419 } 420 } 421 422 UNIONFS_INTERNAL_DEBUG("unionfs_whiteout: leave (%d)\n", error); 423 424 return (error); 425 } 426 427 static int 428 unionfs_mknod(struct vop_mknod_args *ap) 429 { 430 struct unionfs_node *dunp; 431 struct componentname *cnp; 432 struct vnode *udvp; 433 struct vnode *vp; 434 int error; 435 436 UNIONFS_INTERNAL_DEBUG("unionfs_mknod: enter\n"); 437 438 KASSERT_UNIONFS_VNODE(ap->a_dvp); 439 440 dunp = VTOUNIONFS(ap->a_dvp); 441 cnp = ap->a_cnp; 442 udvp = dunp->un_uppervp; 443 error = EROFS; 444 445 if (udvp != NULLVP) { 446 error = VOP_MKNOD(udvp, &vp, cnp, ap->a_vap); 447 if (error != 0) 448 goto unionfs_mknod_abort; 449 450 if (vp->v_type == VSOCK) 451 *(ap->a_vpp) = vp; 452 else { 453 VOP_UNLOCK(vp); 454 error = unionfs_nodeget(ap->a_dvp->v_mount, vp, NULLVP, 455 ap->a_dvp, ap->a_vpp, cnp); 456 vrele(vp); 457 } 458 } 459 460 unionfs_mknod_abort: 461 UNIONFS_INTERNAL_DEBUG("unionfs_mknod: leave (%d)\n", error); 462 463 return (error); 464 } 465 466 enum unionfs_lkupgrade { 467 UNIONFS_LKUPGRADE_SUCCESS, /* lock successfully upgraded */ 468 UNIONFS_LKUPGRADE_ALREADY, /* lock already held exclusive */ 469 UNIONFS_LKUPGRADE_DOOMED /* lock was upgraded, but vnode reclaimed */ 470 }; 471 472 static inline enum unionfs_lkupgrade 473 unionfs_upgrade_lock(struct vnode *vp) 474 { 475 ASSERT_VOP_LOCKED(vp, __func__); 476 477 if (VOP_ISLOCKED(vp) == LK_EXCLUSIVE) 478 return (UNIONFS_LKUPGRADE_ALREADY); 479 480 if (vn_lock(vp, LK_UPGRADE) != 0) { 481 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 482 if (VN_IS_DOOMED(vp)) 483 return (UNIONFS_LKUPGRADE_DOOMED); 484 } 485 return (UNIONFS_LKUPGRADE_SUCCESS); 486 } 487 488 static inline void 489 unionfs_downgrade_lock(struct vnode *vp, enum unionfs_lkupgrade status) 490 { 491 if (status != UNIONFS_LKUPGRADE_ALREADY) 492 vn_lock(vp, LK_DOWNGRADE | LK_RETRY); 493 } 494 495 static int 496 unionfs_open(struct vop_open_args *ap) 497 { 498 struct unionfs_node *unp; 499 struct unionfs_node_status *unsp; 500 struct vnode *vp; 501 struct vnode *uvp; 502 struct vnode *lvp; 503 struct vnode *targetvp; 504 struct ucred *cred; 505 struct thread *td; 506 int error; 507 enum unionfs_lkupgrade lkstatus; 508 509 UNIONFS_INTERNAL_DEBUG("unionfs_open: enter\n"); 510 511 KASSERT_UNIONFS_VNODE(ap->a_vp); 512 513 error = 0; 514 vp = ap->a_vp; 515 targetvp = NULLVP; 516 cred = ap->a_cred; 517 td = ap->a_td; 518 519 /* 520 * The executable loader path may call this function with vp locked 521 * shared. If the vnode is reclaimed while upgrading, we can't safely 522 * use unp or do anything else unionfs- specific. 523 */ 524 lkstatus = unionfs_upgrade_lock(vp); 525 if (lkstatus == UNIONFS_LKUPGRADE_DOOMED) { 526 error = ENOENT; 527 goto unionfs_open_cleanup; 528 } 529 530 unp = VTOUNIONFS(vp); 531 uvp = unp->un_uppervp; 532 lvp = unp->un_lowervp; 533 unionfs_get_node_status(unp, td, &unsp); 534 535 if (unsp->uns_lower_opencnt > 0 || unsp->uns_upper_opencnt > 0) { 536 /* vnode is already opend. */ 537 if (unsp->uns_upper_opencnt > 0) 538 targetvp = uvp; 539 else 540 targetvp = lvp; 541 542 if (targetvp == lvp && 543 (ap->a_mode & FWRITE) && lvp->v_type == VREG) 544 targetvp = NULLVP; 545 } 546 if (targetvp == NULLVP) { 547 if (uvp == NULLVP) { 548 if ((ap->a_mode & FWRITE) && lvp->v_type == VREG) { 549 error = unionfs_copyfile(unp, 550 !(ap->a_mode & O_TRUNC), cred, td); 551 if (error != 0) 552 goto unionfs_open_abort; 553 targetvp = uvp = unp->un_uppervp; 554 } else 555 targetvp = lvp; 556 } else 557 targetvp = uvp; 558 } 559 560 error = VOP_OPEN(targetvp, ap->a_mode, cred, td, ap->a_fp); 561 if (error == 0) { 562 if (targetvp == uvp) { 563 if (uvp->v_type == VDIR && lvp != NULLVP && 564 unsp->uns_lower_opencnt <= 0) { 565 /* open lower for readdir */ 566 error = VOP_OPEN(lvp, FREAD, cred, td, NULL); 567 if (error != 0) { 568 VOP_CLOSE(uvp, ap->a_mode, cred, td); 569 goto unionfs_open_abort; 570 } 571 unsp->uns_node_flag |= UNS_OPENL_4_READDIR; 572 unsp->uns_lower_opencnt++; 573 } 574 unsp->uns_upper_opencnt++; 575 } else { 576 unsp->uns_lower_opencnt++; 577 unsp->uns_lower_openmode = ap->a_mode; 578 } 579 vp->v_object = targetvp->v_object; 580 } 581 582 unionfs_open_abort: 583 if (error != 0) 584 unionfs_tryrem_node_status(unp, unsp); 585 586 unionfs_open_cleanup: 587 unionfs_downgrade_lock(vp, lkstatus); 588 589 UNIONFS_INTERNAL_DEBUG("unionfs_open: leave (%d)\n", error); 590 591 return (error); 592 } 593 594 static int 595 unionfs_close(struct vop_close_args *ap) 596 { 597 struct unionfs_node *unp; 598 struct unionfs_node_status *unsp; 599 struct ucred *cred; 600 struct thread *td; 601 struct vnode *vp; 602 struct vnode *ovp; 603 int error; 604 enum unionfs_lkupgrade lkstatus;; 605 606 UNIONFS_INTERNAL_DEBUG("unionfs_close: enter\n"); 607 608 KASSERT_UNIONFS_VNODE(ap->a_vp); 609 610 vp = ap->a_vp; 611 cred = ap->a_cred; 612 td = ap->a_td; 613 error = 0; 614 615 /* 616 * If the vnode is reclaimed while upgrading, we can't safely use unp 617 * or do anything else unionfs- specific. 618 */ 619 lkstatus = unionfs_upgrade_lock(vp); 620 if (lkstatus == UNIONFS_LKUPGRADE_DOOMED) 621 goto unionfs_close_cleanup; 622 623 unp = VTOUNIONFS(vp); 624 unionfs_get_node_status(unp, td, &unsp); 625 626 if (unsp->uns_lower_opencnt <= 0 && unsp->uns_upper_opencnt <= 0) { 627 #ifdef DIAGNOSTIC 628 printf("unionfs_close: warning: open count is 0\n"); 629 #endif 630 if (unp->un_uppervp != NULLVP) 631 ovp = unp->un_uppervp; 632 else 633 ovp = unp->un_lowervp; 634 } else if (unsp->uns_upper_opencnt > 0) 635 ovp = unp->un_uppervp; 636 else 637 ovp = unp->un_lowervp; 638 639 error = VOP_CLOSE(ovp, ap->a_fflag, cred, td); 640 641 if (error != 0) 642 goto unionfs_close_abort; 643 644 vp->v_object = ovp->v_object; 645 646 if (ovp == unp->un_uppervp) { 647 unsp->uns_upper_opencnt--; 648 if (unsp->uns_upper_opencnt == 0) { 649 if (unsp->uns_node_flag & UNS_OPENL_4_READDIR) { 650 VOP_CLOSE(unp->un_lowervp, FREAD, cred, td); 651 unsp->uns_node_flag &= ~UNS_OPENL_4_READDIR; 652 unsp->uns_lower_opencnt--; 653 } 654 if (unsp->uns_lower_opencnt > 0) 655 vp->v_object = unp->un_lowervp->v_object; 656 } 657 } else 658 unsp->uns_lower_opencnt--; 659 660 unionfs_close_abort: 661 unionfs_tryrem_node_status(unp, unsp); 662 663 unionfs_close_cleanup: 664 unionfs_downgrade_lock(vp, lkstatus); 665 666 UNIONFS_INTERNAL_DEBUG("unionfs_close: leave (%d)\n", error); 667 668 return (error); 669 } 670 671 /* 672 * Check the access mode toward shadow file/dir. 673 */ 674 static int 675 unionfs_check_corrected_access(accmode_t accmode, struct vattr *va, 676 struct ucred *cred) 677 { 678 uid_t uid; /* upper side vnode's uid */ 679 gid_t gid; /* upper side vnode's gid */ 680 u_short vmode; /* upper side vnode's mode */ 681 u_short mask; 682 683 mask = 0; 684 uid = va->va_uid; 685 gid = va->va_gid; 686 vmode = va->va_mode; 687 688 /* check owner */ 689 if (cred->cr_uid == uid) { 690 if (accmode & VEXEC) 691 mask |= S_IXUSR; 692 if (accmode & VREAD) 693 mask |= S_IRUSR; 694 if (accmode & VWRITE) 695 mask |= S_IWUSR; 696 return ((vmode & mask) == mask ? 0 : EACCES); 697 } 698 699 /* check group */ 700 if (groupmember(gid, cred)) { 701 if (accmode & VEXEC) 702 mask |= S_IXGRP; 703 if (accmode & VREAD) 704 mask |= S_IRGRP; 705 if (accmode & VWRITE) 706 mask |= S_IWGRP; 707 return ((vmode & mask) == mask ? 0 : EACCES); 708 } 709 710 /* check other */ 711 if (accmode & VEXEC) 712 mask |= S_IXOTH; 713 if (accmode & VREAD) 714 mask |= S_IROTH; 715 if (accmode & VWRITE) 716 mask |= S_IWOTH; 717 718 return ((vmode & mask) == mask ? 0 : EACCES); 719 } 720 721 static int 722 unionfs_access(struct vop_access_args *ap) 723 { 724 struct unionfs_mount *ump; 725 struct unionfs_node *unp; 726 struct vnode *uvp; 727 struct vnode *lvp; 728 struct thread *td; 729 struct vattr va; 730 accmode_t accmode; 731 int error; 732 733 UNIONFS_INTERNAL_DEBUG("unionfs_access: enter\n"); 734 735 KASSERT_UNIONFS_VNODE(ap->a_vp); 736 737 ump = MOUNTTOUNIONFSMOUNT(ap->a_vp->v_mount); 738 unp = VTOUNIONFS(ap->a_vp); 739 uvp = unp->un_uppervp; 740 lvp = unp->un_lowervp; 741 td = ap->a_td; 742 accmode = ap->a_accmode; 743 error = EACCES; 744 745 if ((accmode & VWRITE) && 746 (ap->a_vp->v_mount->mnt_flag & MNT_RDONLY)) { 747 switch (ap->a_vp->v_type) { 748 case VREG: 749 case VDIR: 750 case VLNK: 751 return (EROFS); 752 default: 753 break; 754 } 755 } 756 757 if (uvp != NULLVP) { 758 error = VOP_ACCESS(uvp, accmode, ap->a_cred, td); 759 760 UNIONFS_INTERNAL_DEBUG("unionfs_access: leave (%d)\n", error); 761 762 return (error); 763 } 764 765 if (lvp != NULLVP) { 766 if (accmode & VWRITE) { 767 if (ump->um_uppervp->v_mount->mnt_flag & MNT_RDONLY) { 768 switch (ap->a_vp->v_type) { 769 case VREG: 770 case VDIR: 771 case VLNK: 772 return (EROFS); 773 default: 774 break; 775 } 776 } else if (ap->a_vp->v_type == VREG || 777 ap->a_vp->v_type == VDIR) { 778 /* check shadow file/dir */ 779 if (ump->um_copymode != UNIONFS_TRANSPARENT) { 780 error = unionfs_create_uppervattr(ump, 781 lvp, &va, ap->a_cred, td); 782 if (error != 0) 783 return (error); 784 785 error = unionfs_check_corrected_access( 786 accmode, &va, ap->a_cred); 787 if (error != 0) 788 return (error); 789 } 790 } 791 accmode &= ~(VWRITE | VAPPEND); 792 accmode |= VREAD; /* will copy to upper */ 793 } 794 error = VOP_ACCESS(lvp, accmode, ap->a_cred, td); 795 } 796 797 UNIONFS_INTERNAL_DEBUG("unionfs_access: leave (%d)\n", error); 798 799 return (error); 800 } 801 802 static int 803 unionfs_getattr(struct vop_getattr_args *ap) 804 { 805 struct unionfs_node *unp; 806 struct unionfs_mount *ump; 807 struct vnode *uvp; 808 struct vnode *lvp; 809 struct thread *td; 810 struct vattr va; 811 int error; 812 813 UNIONFS_INTERNAL_DEBUG("unionfs_getattr: enter\n"); 814 815 KASSERT_UNIONFS_VNODE(ap->a_vp); 816 817 unp = VTOUNIONFS(ap->a_vp); 818 ump = MOUNTTOUNIONFSMOUNT(ap->a_vp->v_mount); 819 uvp = unp->un_uppervp; 820 lvp = unp->un_lowervp; 821 td = curthread; 822 823 if (uvp != NULLVP) { 824 if ((error = VOP_GETATTR(uvp, ap->a_vap, ap->a_cred)) == 0) 825 ap->a_vap->va_fsid = 826 ap->a_vp->v_mount->mnt_stat.f_fsid.val[0]; 827 828 UNIONFS_INTERNAL_DEBUG( 829 "unionfs_getattr: leave mode=%o, uid=%d, gid=%d (%d)\n", 830 ap->a_vap->va_mode, ap->a_vap->va_uid, 831 ap->a_vap->va_gid, error); 832 833 return (error); 834 } 835 836 error = VOP_GETATTR(lvp, ap->a_vap, ap->a_cred); 837 838 if (error == 0 && !(ump->um_uppervp->v_mount->mnt_flag & MNT_RDONLY)) { 839 /* correct the attr toward shadow file/dir. */ 840 if (ap->a_vp->v_type == VREG || ap->a_vp->v_type == VDIR) { 841 unionfs_create_uppervattr_core(ump, ap->a_vap, &va, td); 842 ap->a_vap->va_mode = va.va_mode; 843 ap->a_vap->va_uid = va.va_uid; 844 ap->a_vap->va_gid = va.va_gid; 845 } 846 } 847 848 if (error == 0) 849 ap->a_vap->va_fsid = ap->a_vp->v_mount->mnt_stat.f_fsid.val[0]; 850 851 UNIONFS_INTERNAL_DEBUG( 852 "unionfs_getattr: leave mode=%o, uid=%d, gid=%d (%d)\n", 853 ap->a_vap->va_mode, ap->a_vap->va_uid, ap->a_vap->va_gid, error); 854 855 return (error); 856 } 857 858 static int 859 unionfs_setattr(struct vop_setattr_args *ap) 860 { 861 struct unionfs_node *unp; 862 struct vnode *uvp; 863 struct vnode *lvp; 864 struct thread *td; 865 struct vattr *vap; 866 int error; 867 868 UNIONFS_INTERNAL_DEBUG("unionfs_setattr: enter\n"); 869 870 KASSERT_UNIONFS_VNODE(ap->a_vp); 871 872 error = EROFS; 873 unp = VTOUNIONFS(ap->a_vp); 874 uvp = unp->un_uppervp; 875 lvp = unp->un_lowervp; 876 td = curthread; 877 vap = ap->a_vap; 878 879 if ((ap->a_vp->v_mount->mnt_flag & MNT_RDONLY) && 880 (vap->va_flags != VNOVAL || vap->va_uid != (uid_t)VNOVAL || 881 vap->va_gid != (gid_t)VNOVAL || vap->va_atime.tv_sec != VNOVAL || 882 vap->va_mtime.tv_sec != VNOVAL || vap->va_mode != (mode_t)VNOVAL)) 883 return (EROFS); 884 885 if (uvp == NULLVP && lvp->v_type == VREG) { 886 error = unionfs_copyfile(unp, (vap->va_size != 0), 887 ap->a_cred, td); 888 if (error != 0) 889 return (error); 890 uvp = unp->un_uppervp; 891 } 892 893 if (uvp != NULLVP) 894 error = VOP_SETATTR(uvp, vap, ap->a_cred); 895 896 UNIONFS_INTERNAL_DEBUG("unionfs_setattr: leave (%d)\n", error); 897 898 return (error); 899 } 900 901 static int 902 unionfs_read(struct vop_read_args *ap) 903 { 904 struct unionfs_node *unp; 905 struct vnode *tvp; 906 int error; 907 908 /* UNIONFS_INTERNAL_DEBUG("unionfs_read: enter\n"); */ 909 910 KASSERT_UNIONFS_VNODE(ap->a_vp); 911 912 unp = VTOUNIONFS(ap->a_vp); 913 tvp = (unp->un_uppervp != NULLVP ? unp->un_uppervp : unp->un_lowervp); 914 915 error = VOP_READ(tvp, ap->a_uio, ap->a_ioflag, ap->a_cred); 916 917 /* UNIONFS_INTERNAL_DEBUG("unionfs_read: leave (%d)\n", error); */ 918 919 return (error); 920 } 921 922 static int 923 unionfs_write(struct vop_write_args *ap) 924 { 925 struct unionfs_node *unp; 926 struct vnode *tvp; 927 int error; 928 929 /* UNIONFS_INTERNAL_DEBUG("unionfs_write: enter\n"); */ 930 931 KASSERT_UNIONFS_VNODE(ap->a_vp); 932 933 unp = VTOUNIONFS(ap->a_vp); 934 tvp = (unp->un_uppervp != NULLVP ? unp->un_uppervp : unp->un_lowervp); 935 936 error = VOP_WRITE(tvp, ap->a_uio, ap->a_ioflag, ap->a_cred); 937 938 /* UNIONFS_INTERNAL_DEBUG("unionfs_write: leave (%d)\n", error); */ 939 940 return (error); 941 } 942 943 static int 944 unionfs_ioctl(struct vop_ioctl_args *ap) 945 { 946 struct unionfs_node *unp; 947 struct unionfs_node_status *unsp; 948 struct vnode *ovp; 949 int error; 950 951 UNIONFS_INTERNAL_DEBUG("unionfs_ioctl: enter\n"); 952 953 KASSERT_UNIONFS_VNODE(ap->a_vp); 954 955 vn_lock(ap->a_vp, LK_EXCLUSIVE | LK_RETRY); 956 unp = VTOUNIONFS(ap->a_vp); 957 unionfs_get_node_status(unp, ap->a_td, &unsp); 958 ovp = (unsp->uns_upper_opencnt ? unp->un_uppervp : unp->un_lowervp); 959 unionfs_tryrem_node_status(unp, unsp); 960 VOP_UNLOCK(ap->a_vp); 961 962 if (ovp == NULLVP) 963 return (EBADF); 964 965 error = VOP_IOCTL(ovp, ap->a_command, ap->a_data, ap->a_fflag, 966 ap->a_cred, ap->a_td); 967 968 UNIONFS_INTERNAL_DEBUG("unionfs_ioctl: leave (%d)\n", error); 969 970 return (error); 971 } 972 973 static int 974 unionfs_poll(struct vop_poll_args *ap) 975 { 976 struct unionfs_node *unp; 977 struct unionfs_node_status *unsp; 978 struct vnode *ovp; 979 980 KASSERT_UNIONFS_VNODE(ap->a_vp); 981 982 vn_lock(ap->a_vp, LK_EXCLUSIVE | LK_RETRY); 983 unp = VTOUNIONFS(ap->a_vp); 984 unionfs_get_node_status(unp, ap->a_td, &unsp); 985 ovp = (unsp->uns_upper_opencnt ? unp->un_uppervp : unp->un_lowervp); 986 unionfs_tryrem_node_status(unp, unsp); 987 VOP_UNLOCK(ap->a_vp); 988 989 if (ovp == NULLVP) 990 return (EBADF); 991 992 return (VOP_POLL(ovp, ap->a_events, ap->a_cred, ap->a_td)); 993 } 994 995 static int 996 unionfs_fsync(struct vop_fsync_args *ap) 997 { 998 struct unionfs_node *unp; 999 struct unionfs_node_status *unsp; 1000 struct vnode *ovp; 1001 1002 KASSERT_UNIONFS_VNODE(ap->a_vp); 1003 1004 unp = VTOUNIONFS(ap->a_vp); 1005 unionfs_get_node_status(unp, ap->a_td, &unsp); 1006 ovp = (unsp->uns_upper_opencnt ? unp->un_uppervp : unp->un_lowervp); 1007 unionfs_tryrem_node_status(unp, unsp); 1008 1009 if (ovp == NULLVP) 1010 return (EBADF); 1011 1012 return (VOP_FSYNC(ovp, ap->a_waitfor, ap->a_td)); 1013 } 1014 1015 static int 1016 unionfs_remove(struct vop_remove_args *ap) 1017 { 1018 char *path; 1019 struct unionfs_node *dunp; 1020 struct unionfs_node *unp; 1021 struct unionfs_mount *ump; 1022 struct vnode *udvp; 1023 struct vnode *uvp; 1024 struct vnode *lvp; 1025 struct vnode *vp; 1026 struct componentname *cnp; 1027 struct componentname cn; 1028 struct thread *td; 1029 int error; 1030 int pathlen; 1031 1032 UNIONFS_INTERNAL_DEBUG("unionfs_remove: enter\n"); 1033 1034 KASSERT_UNIONFS_VNODE(ap->a_dvp); 1035 1036 error = 0; 1037 dunp = VTOUNIONFS(ap->a_dvp); 1038 udvp = dunp->un_uppervp; 1039 cnp = ap->a_cnp; 1040 td = curthread; 1041 1042 if (ap->a_vp->v_op != &unionfs_vnodeops) { 1043 if (ap->a_vp->v_type != VSOCK) 1044 return (EINVAL); 1045 ump = NULL; 1046 vp = uvp = lvp = NULLVP; 1047 /* search vnode */ 1048 VOP_UNLOCK(ap->a_vp); 1049 error = unionfs_relookup(udvp, &vp, cnp, &cn, td, 1050 cnp->cn_nameptr, cnp->cn_namelen, DELETE); 1051 if (error != 0 && error != ENOENT) { 1052 vn_lock(ap->a_vp, LK_EXCLUSIVE | LK_RETRY); 1053 return (error); 1054 } 1055 1056 if (error == 0 && vp == ap->a_vp) { 1057 /* target vnode in upper */ 1058 uvp = vp; 1059 vrele(vp); 1060 } else { 1061 /* target vnode in lower */ 1062 if (vp != NULLVP) { 1063 if (udvp == vp) 1064 vrele(vp); 1065 else 1066 vput(vp); 1067 } 1068 vn_lock(ap->a_vp, LK_EXCLUSIVE | LK_RETRY); 1069 lvp = ap->a_vp; 1070 } 1071 path = cnp->cn_nameptr; 1072 pathlen = cnp->cn_namelen; 1073 } else { 1074 ump = MOUNTTOUNIONFSMOUNT(ap->a_vp->v_mount); 1075 unp = VTOUNIONFS(ap->a_vp); 1076 uvp = unp->un_uppervp; 1077 lvp = unp->un_lowervp; 1078 path = unp->un_path; 1079 pathlen = unp->un_pathlen; 1080 } 1081 1082 if (udvp == NULLVP) 1083 return (EROFS); 1084 1085 if (uvp != NULLVP) { 1086 /* 1087 * XXX: if the vnode type is VSOCK, it will create whiteout 1088 * after remove. 1089 */ 1090 if (ump == NULL || ump->um_whitemode == UNIONFS_WHITE_ALWAYS || 1091 lvp != NULLVP) 1092 cnp->cn_flags |= DOWHITEOUT; 1093 error = VOP_REMOVE(udvp, uvp, cnp); 1094 } else if (lvp != NULLVP) 1095 error = unionfs_mkwhiteout(udvp, cnp, td, path, pathlen); 1096 1097 UNIONFS_INTERNAL_DEBUG("unionfs_remove: leave (%d)\n", error); 1098 1099 return (error); 1100 } 1101 1102 static int 1103 unionfs_link(struct vop_link_args *ap) 1104 { 1105 struct unionfs_node *dunp; 1106 struct unionfs_node *unp; 1107 struct vnode *udvp; 1108 struct vnode *uvp; 1109 struct componentname *cnp; 1110 struct thread *td; 1111 int error; 1112 int needrelookup; 1113 1114 UNIONFS_INTERNAL_DEBUG("unionfs_link: enter\n"); 1115 1116 KASSERT_UNIONFS_VNODE(ap->a_tdvp); 1117 KASSERT_UNIONFS_VNODE(ap->a_vp); 1118 1119 error = 0; 1120 needrelookup = 0; 1121 dunp = VTOUNIONFS(ap->a_tdvp); 1122 unp = NULL; 1123 udvp = dunp->un_uppervp; 1124 uvp = NULLVP; 1125 cnp = ap->a_cnp; 1126 td = curthread; 1127 1128 if (udvp == NULLVP) 1129 return (EROFS); 1130 1131 if (ap->a_vp->v_op != &unionfs_vnodeops) 1132 uvp = ap->a_vp; 1133 else { 1134 unp = VTOUNIONFS(ap->a_vp); 1135 1136 if (unp->un_uppervp == NULLVP) { 1137 if (ap->a_vp->v_type != VREG) 1138 return (EOPNOTSUPP); 1139 1140 error = unionfs_copyfile(unp, 1, cnp->cn_cred, td); 1141 if (error != 0) 1142 return (error); 1143 needrelookup = 1; 1144 } 1145 uvp = unp->un_uppervp; 1146 } 1147 1148 if (needrelookup != 0) 1149 error = unionfs_relookup_for_create(ap->a_tdvp, cnp, td); 1150 1151 if (error == 0) 1152 error = VOP_LINK(udvp, uvp, cnp); 1153 1154 UNIONFS_INTERNAL_DEBUG("unionfs_link: leave (%d)\n", error); 1155 1156 return (error); 1157 } 1158 1159 static int 1160 unionfs_rename(struct vop_rename_args *ap) 1161 { 1162 struct vnode *fdvp; 1163 struct vnode *fvp; 1164 struct componentname *fcnp; 1165 struct vnode *tdvp; 1166 struct vnode *tvp; 1167 struct componentname *tcnp; 1168 struct vnode *ltdvp; 1169 struct vnode *ltvp; 1170 struct thread *td; 1171 1172 /* rename target vnodes */ 1173 struct vnode *rfdvp; 1174 struct vnode *rfvp; 1175 struct vnode *rtdvp; 1176 struct vnode *rtvp; 1177 1178 struct unionfs_mount *ump; 1179 struct unionfs_node *unp; 1180 int error; 1181 int needrelookup; 1182 1183 UNIONFS_INTERNAL_DEBUG("unionfs_rename: enter\n"); 1184 1185 error = 0; 1186 fdvp = ap->a_fdvp; 1187 fvp = ap->a_fvp; 1188 fcnp = ap->a_fcnp; 1189 tdvp = ap->a_tdvp; 1190 tvp = ap->a_tvp; 1191 tcnp = ap->a_tcnp; 1192 ltdvp = NULLVP; 1193 ltvp = NULLVP; 1194 td = curthread; 1195 rfdvp = fdvp; 1196 rfvp = fvp; 1197 rtdvp = tdvp; 1198 rtvp = tvp; 1199 needrelookup = 0; 1200 1201 /* check for cross device rename */ 1202 if (fvp->v_mount != tdvp->v_mount || 1203 (tvp != NULLVP && fvp->v_mount != tvp->v_mount)) { 1204 if (fvp->v_op != &unionfs_vnodeops) 1205 error = ENODEV; 1206 else 1207 error = EXDEV; 1208 goto unionfs_rename_abort; 1209 } 1210 1211 /* Renaming a file to itself has no effect. */ 1212 if (fvp == tvp) 1213 goto unionfs_rename_abort; 1214 1215 /* 1216 * from/to vnode is unionfs node. 1217 */ 1218 1219 KASSERT_UNIONFS_VNODE(fdvp); 1220 KASSERT_UNIONFS_VNODE(fvp); 1221 KASSERT_UNIONFS_VNODE(tdvp); 1222 if (tvp != NULLVP) 1223 KASSERT_UNIONFS_VNODE(tvp); 1224 1225 unp = VTOUNIONFS(fdvp); 1226 #ifdef UNIONFS_IDBG_RENAME 1227 UNIONFS_INTERNAL_DEBUG("fdvp=%p, ufdvp=%p, lfdvp=%p\n", 1228 fdvp, unp->un_uppervp, unp->un_lowervp); 1229 #endif 1230 if (unp->un_uppervp == NULLVP) { 1231 error = ENODEV; 1232 goto unionfs_rename_abort; 1233 } 1234 rfdvp = unp->un_uppervp; 1235 vref(rfdvp); 1236 1237 unp = VTOUNIONFS(fvp); 1238 #ifdef UNIONFS_IDBG_RENAME 1239 UNIONFS_INTERNAL_DEBUG("fvp=%p, ufvp=%p, lfvp=%p\n", 1240 fvp, unp->un_uppervp, unp->un_lowervp); 1241 #endif 1242 ump = MOUNTTOUNIONFSMOUNT(fvp->v_mount); 1243 if (unp->un_uppervp == NULLVP) { 1244 switch (fvp->v_type) { 1245 case VREG: 1246 if ((error = vn_lock(fvp, LK_EXCLUSIVE)) != 0) 1247 goto unionfs_rename_abort; 1248 error = unionfs_copyfile(unp, 1, fcnp->cn_cred, td); 1249 VOP_UNLOCK(fvp); 1250 if (error != 0) 1251 goto unionfs_rename_abort; 1252 break; 1253 case VDIR: 1254 if ((error = vn_lock(fvp, LK_EXCLUSIVE)) != 0) 1255 goto unionfs_rename_abort; 1256 error = unionfs_mkshadowdir(ump, rfdvp, unp, fcnp, td); 1257 VOP_UNLOCK(fvp); 1258 if (error != 0) 1259 goto unionfs_rename_abort; 1260 break; 1261 default: 1262 error = ENODEV; 1263 goto unionfs_rename_abort; 1264 } 1265 1266 needrelookup = 1; 1267 } 1268 1269 if (unp->un_lowervp != NULLVP) 1270 fcnp->cn_flags |= DOWHITEOUT; 1271 rfvp = unp->un_uppervp; 1272 vref(rfvp); 1273 1274 unp = VTOUNIONFS(tdvp); 1275 #ifdef UNIONFS_IDBG_RENAME 1276 UNIONFS_INTERNAL_DEBUG("tdvp=%p, utdvp=%p, ltdvp=%p\n", 1277 tdvp, unp->un_uppervp, unp->un_lowervp); 1278 #endif 1279 if (unp->un_uppervp == NULLVP) { 1280 error = ENODEV; 1281 goto unionfs_rename_abort; 1282 } 1283 rtdvp = unp->un_uppervp; 1284 ltdvp = unp->un_lowervp; 1285 vref(rtdvp); 1286 1287 if (tdvp == tvp) { 1288 rtvp = rtdvp; 1289 vref(rtvp); 1290 } else if (tvp != NULLVP) { 1291 unp = VTOUNIONFS(tvp); 1292 #ifdef UNIONFS_IDBG_RENAME 1293 UNIONFS_INTERNAL_DEBUG("tvp=%p, utvp=%p, ltvp=%p\n", 1294 tvp, unp->un_uppervp, unp->un_lowervp); 1295 #endif 1296 if (unp->un_uppervp == NULLVP) 1297 rtvp = NULLVP; 1298 else { 1299 if (tvp->v_type == VDIR) { 1300 error = EINVAL; 1301 goto unionfs_rename_abort; 1302 } 1303 rtvp = unp->un_uppervp; 1304 ltvp = unp->un_lowervp; 1305 vref(rtvp); 1306 } 1307 } 1308 1309 if (rfvp == rtvp) 1310 goto unionfs_rename_abort; 1311 1312 if (needrelookup != 0) { 1313 if ((error = vn_lock(fdvp, LK_EXCLUSIVE)) != 0) 1314 goto unionfs_rename_abort; 1315 error = unionfs_relookup_for_delete(fdvp, fcnp, td); 1316 VOP_UNLOCK(fdvp); 1317 if (error != 0) 1318 goto unionfs_rename_abort; 1319 1320 /* Lock of tvp is canceled in order to avoid recursive lock. */ 1321 if (tvp != NULLVP && tvp != tdvp) 1322 VOP_UNLOCK(tvp); 1323 error = unionfs_relookup_for_rename(tdvp, tcnp, td); 1324 if (tvp != NULLVP && tvp != tdvp) 1325 vn_lock(tvp, LK_EXCLUSIVE | LK_RETRY); 1326 if (error != 0) 1327 goto unionfs_rename_abort; 1328 } 1329 1330 error = VOP_RENAME(rfdvp, rfvp, fcnp, rtdvp, rtvp, tcnp); 1331 1332 if (error == 0) { 1333 if (rtvp != NULLVP && rtvp->v_type == VDIR) 1334 cache_purge(tdvp); 1335 if (fvp->v_type == VDIR && fdvp != tdvp) 1336 cache_purge(fdvp); 1337 } 1338 1339 if (ltdvp != NULLVP) 1340 VOP_UNLOCK(ltdvp); 1341 if (tdvp != rtdvp) 1342 vrele(tdvp); 1343 if (ltvp != NULLVP) 1344 VOP_UNLOCK(ltvp); 1345 if (tvp != rtvp && tvp != NULLVP) { 1346 if (rtvp == NULLVP) 1347 vput(tvp); 1348 else 1349 vrele(tvp); 1350 } 1351 if (fdvp != rfdvp) 1352 vrele(fdvp); 1353 if (fvp != rfvp) 1354 vrele(fvp); 1355 1356 UNIONFS_INTERNAL_DEBUG("unionfs_rename: leave (%d)\n", error); 1357 1358 return (error); 1359 1360 unionfs_rename_abort: 1361 vput(tdvp); 1362 if (tdvp != rtdvp) 1363 vrele(rtdvp); 1364 if (tvp != NULLVP) { 1365 if (tdvp != tvp) 1366 vput(tvp); 1367 else 1368 vrele(tvp); 1369 } 1370 if (tvp != rtvp && rtvp != NULLVP) 1371 vrele(rtvp); 1372 if (fdvp != rfdvp) 1373 vrele(rfdvp); 1374 if (fvp != rfvp) 1375 vrele(rfvp); 1376 vrele(fdvp); 1377 vrele(fvp); 1378 1379 UNIONFS_INTERNAL_DEBUG("unionfs_rename: leave (%d)\n", error); 1380 1381 return (error); 1382 } 1383 1384 static int 1385 unionfs_mkdir(struct vop_mkdir_args *ap) 1386 { 1387 struct unionfs_node *dunp; 1388 struct componentname *cnp; 1389 struct vnode *dvp; 1390 struct vnode *udvp; 1391 struct vnode *uvp; 1392 struct vattr va; 1393 int error; 1394 int lkflags; 1395 1396 UNIONFS_INTERNAL_DEBUG("unionfs_mkdir: enter\n"); 1397 1398 KASSERT_UNIONFS_VNODE(ap->a_dvp); 1399 1400 error = EROFS; 1401 dvp = ap->a_dvp; 1402 dunp = VTOUNIONFS(dvp); 1403 cnp = ap->a_cnp; 1404 lkflags = cnp->cn_lkflags; 1405 udvp = dunp->un_uppervp; 1406 1407 if (udvp != NULLVP) { 1408 vref(udvp); 1409 /* check opaque */ 1410 if (!(cnp->cn_flags & ISWHITEOUT)) { 1411 error = VOP_GETATTR(udvp, &va, cnp->cn_cred); 1412 if (error != 0) 1413 goto unionfs_mkdir_cleanup; 1414 if ((va.va_flags & OPAQUE) != 0) 1415 cnp->cn_flags |= ISWHITEOUT; 1416 } 1417 1418 if ((error = VOP_MKDIR(udvp, &uvp, cnp, ap->a_vap)) == 0) { 1419 VOP_UNLOCK(uvp); 1420 cnp->cn_lkflags = LK_EXCLUSIVE; 1421 /* 1422 * The underlying VOP_MKDIR() implementation may have 1423 * temporarily dropped the parent directory vnode lock. 1424 * Because the unionfs vnode ordinarily shares that 1425 * lock, this may allow the unionfs vnode to be reclaimed 1426 * and its lock field reset. In that case, the unionfs 1427 * vnode is effectively no longer locked, and we must 1428 * explicitly lock it before returning in order to meet 1429 * the locking requirements of VOP_MKDIR(). 1430 */ 1431 if (__predict_false(VTOUNIONFS(dvp) == NULL)) { 1432 error = ENOENT; 1433 goto unionfs_mkdir_cleanup; 1434 } 1435 error = unionfs_nodeget(dvp->v_mount, uvp, NULLVP, 1436 dvp, ap->a_vpp, cnp); 1437 cnp->cn_lkflags = lkflags; 1438 vrele(uvp); 1439 } 1440 } 1441 1442 unionfs_mkdir_cleanup: 1443 1444 if (__predict_false(VTOUNIONFS(dvp) == NULL)) { 1445 vput(udvp); 1446 vn_lock(dvp, LK_EXCLUSIVE | LK_RETRY); 1447 } else if (udvp != NULLVP) 1448 vrele(udvp); 1449 1450 UNIONFS_INTERNAL_DEBUG("unionfs_mkdir: leave (%d)\n", error); 1451 1452 return (error); 1453 } 1454 1455 static int 1456 unionfs_rmdir(struct vop_rmdir_args *ap) 1457 { 1458 struct unionfs_node *dunp; 1459 struct unionfs_node *unp; 1460 struct unionfs_mount *ump; 1461 struct componentname *cnp; 1462 struct thread *td; 1463 struct vnode *udvp; 1464 struct vnode *uvp; 1465 struct vnode *lvp; 1466 int error; 1467 1468 UNIONFS_INTERNAL_DEBUG("unionfs_rmdir: enter\n"); 1469 1470 KASSERT_UNIONFS_VNODE(ap->a_dvp); 1471 KASSERT_UNIONFS_VNODE(ap->a_vp); 1472 1473 error = 0; 1474 dunp = VTOUNIONFS(ap->a_dvp); 1475 unp = VTOUNIONFS(ap->a_vp); 1476 cnp = ap->a_cnp; 1477 td = curthread; 1478 udvp = dunp->un_uppervp; 1479 uvp = unp->un_uppervp; 1480 lvp = unp->un_lowervp; 1481 1482 if (udvp == NULLVP) 1483 return (EROFS); 1484 1485 if (udvp == uvp) 1486 return (EOPNOTSUPP); 1487 1488 if (uvp != NULLVP) { 1489 if (lvp != NULLVP) { 1490 error = unionfs_check_rmdir(ap->a_vp, cnp->cn_cred, td); 1491 if (error != 0) 1492 return (error); 1493 } 1494 ump = MOUNTTOUNIONFSMOUNT(ap->a_vp->v_mount); 1495 if (ump->um_whitemode == UNIONFS_WHITE_ALWAYS || lvp != NULLVP) 1496 cnp->cn_flags |= DOWHITEOUT; 1497 /* 1498 * The relookup path will need to relock the parent dvp and 1499 * possibly the vp as well. Locking is expected to be done 1500 * in parent->child order; drop the lock on vp to avoid LOR 1501 * and potential recursion on vp's lock. 1502 * vp is expected to remain referenced during VOP_RMDIR(), 1503 * so vref/vrele should not be necessary here. 1504 */ 1505 VOP_UNLOCK(ap->a_vp); 1506 VNPASS(vrefcnt(ap->a_vp) > 0, ap->a_vp); 1507 error = unionfs_relookup_for_delete(ap->a_dvp, cnp, td); 1508 vn_lock(ap->a_vp, LK_EXCLUSIVE | LK_RETRY); 1509 /* 1510 * VOP_RMDIR is dispatched against udvp, so if uvp became 1511 * doomed while the lock was dropped above the target 1512 * filesystem may not be able to cope. 1513 */ 1514 if (error == 0 && VN_IS_DOOMED(uvp)) 1515 error = ENOENT; 1516 if (error == 0) 1517 error = VOP_RMDIR(udvp, uvp, cnp); 1518 } else if (lvp != NULLVP) 1519 error = unionfs_mkwhiteout(udvp, cnp, td, 1520 unp->un_path, unp->un_pathlen); 1521 1522 if (error == 0) { 1523 cache_purge(ap->a_dvp); 1524 cache_purge(ap->a_vp); 1525 } 1526 1527 UNIONFS_INTERNAL_DEBUG("unionfs_rmdir: leave (%d)\n", error); 1528 1529 return (error); 1530 } 1531 1532 static int 1533 unionfs_symlink(struct vop_symlink_args *ap) 1534 { 1535 struct unionfs_node *dunp; 1536 struct componentname *cnp; 1537 struct vnode *udvp; 1538 struct vnode *uvp; 1539 int error; 1540 int lkflags; 1541 1542 UNIONFS_INTERNAL_DEBUG("unionfs_symlink: enter\n"); 1543 1544 KASSERT_UNIONFS_VNODE(ap->a_dvp); 1545 1546 error = EROFS; 1547 dunp = VTOUNIONFS(ap->a_dvp); 1548 cnp = ap->a_cnp; 1549 lkflags = cnp->cn_lkflags; 1550 udvp = dunp->un_uppervp; 1551 1552 if (udvp != NULLVP) { 1553 error = VOP_SYMLINK(udvp, &uvp, cnp, ap->a_vap, ap->a_target); 1554 if (error == 0) { 1555 VOP_UNLOCK(uvp); 1556 cnp->cn_lkflags = LK_EXCLUSIVE; 1557 error = unionfs_nodeget(ap->a_dvp->v_mount, uvp, NULLVP, 1558 ap->a_dvp, ap->a_vpp, cnp); 1559 cnp->cn_lkflags = lkflags; 1560 vrele(uvp); 1561 } 1562 } 1563 1564 UNIONFS_INTERNAL_DEBUG("unionfs_symlink: leave (%d)\n", error); 1565 1566 return (error); 1567 } 1568 1569 static int 1570 unionfs_readdir(struct vop_readdir_args *ap) 1571 { 1572 struct unionfs_node *unp; 1573 struct unionfs_node_status *unsp; 1574 struct uio *uio; 1575 struct vnode *vp; 1576 struct vnode *uvp; 1577 struct vnode *lvp; 1578 struct thread *td; 1579 struct vattr va; 1580 1581 uint64_t *cookies_bk; 1582 int error; 1583 int eofflag; 1584 int ncookies_bk; 1585 int uio_offset_bk; 1586 enum unionfs_lkupgrade lkstatus; 1587 1588 UNIONFS_INTERNAL_DEBUG("unionfs_readdir: enter\n"); 1589 1590 KASSERT_UNIONFS_VNODE(ap->a_vp); 1591 1592 error = 0; 1593 eofflag = 0; 1594 uio_offset_bk = 0; 1595 uio = ap->a_uio; 1596 uvp = NULLVP; 1597 lvp = NULLVP; 1598 td = uio->uio_td; 1599 ncookies_bk = 0; 1600 cookies_bk = NULL; 1601 1602 vp = ap->a_vp; 1603 if (vp->v_type != VDIR) 1604 return (ENOTDIR); 1605 1606 /* 1607 * If the vnode is reclaimed while upgrading, we can't safely use unp 1608 * or do anything else unionfs- specific. 1609 */ 1610 lkstatus = unionfs_upgrade_lock(vp); 1611 if (lkstatus == UNIONFS_LKUPGRADE_DOOMED) 1612 error = EBADF; 1613 if (error == 0) { 1614 unp = VTOUNIONFS(vp); 1615 uvp = unp->un_uppervp; 1616 lvp = unp->un_lowervp; 1617 /* check the open count. unionfs needs open before readdir. */ 1618 unionfs_get_node_status(unp, td, &unsp); 1619 if ((uvp != NULLVP && unsp->uns_upper_opencnt <= 0) || 1620 (lvp != NULLVP && unsp->uns_lower_opencnt <= 0)) { 1621 unionfs_tryrem_node_status(unp, unsp); 1622 error = EBADF; 1623 } 1624 } 1625 unionfs_downgrade_lock(vp, lkstatus); 1626 if (error != 0) 1627 goto unionfs_readdir_exit; 1628 1629 /* check opaque */ 1630 if (uvp != NULLVP && lvp != NULLVP) { 1631 if ((error = VOP_GETATTR(uvp, &va, ap->a_cred)) != 0) 1632 goto unionfs_readdir_exit; 1633 if (va.va_flags & OPAQUE) 1634 lvp = NULLVP; 1635 } 1636 1637 /* upper only */ 1638 if (uvp != NULLVP && lvp == NULLVP) { 1639 error = VOP_READDIR(uvp, uio, ap->a_cred, ap->a_eofflag, 1640 ap->a_ncookies, ap->a_cookies); 1641 unsp->uns_readdir_status = 0; 1642 1643 goto unionfs_readdir_exit; 1644 } 1645 1646 /* lower only */ 1647 if (uvp == NULLVP && lvp != NULLVP) { 1648 error = VOP_READDIR(lvp, uio, ap->a_cred, ap->a_eofflag, 1649 ap->a_ncookies, ap->a_cookies); 1650 unsp->uns_readdir_status = 2; 1651 1652 goto unionfs_readdir_exit; 1653 } 1654 1655 /* 1656 * readdir upper and lower 1657 */ 1658 KASSERT(uvp != NULLVP, ("unionfs_readdir: null upper vp")); 1659 KASSERT(lvp != NULLVP, ("unionfs_readdir: null lower vp")); 1660 if (uio->uio_offset == 0) 1661 unsp->uns_readdir_status = 0; 1662 1663 if (unsp->uns_readdir_status == 0) { 1664 /* read upper */ 1665 error = VOP_READDIR(uvp, uio, ap->a_cred, &eofflag, 1666 ap->a_ncookies, ap->a_cookies); 1667 1668 if (error != 0 || eofflag == 0) 1669 goto unionfs_readdir_exit; 1670 unsp->uns_readdir_status = 1; 1671 1672 /* 1673 * UFS(and other FS) needs size of uio_resid larger than 1674 * DIRBLKSIZ. 1675 * size of DIRBLKSIZ equals DEV_BSIZE. 1676 * (see: ufs/ufs/ufs_vnops.c ufs_readdir func , ufs/ufs/dir.h) 1677 */ 1678 if (uio->uio_resid <= (uio->uio_resid & (DEV_BSIZE -1))) 1679 goto unionfs_readdir_exit; 1680 1681 /* 1682 * Backup cookies. 1683 * It prepares to readdir in lower. 1684 */ 1685 if (ap->a_ncookies != NULL) { 1686 ncookies_bk = *(ap->a_ncookies); 1687 *(ap->a_ncookies) = 0; 1688 } 1689 if (ap->a_cookies != NULL) { 1690 cookies_bk = *(ap->a_cookies); 1691 *(ap->a_cookies) = NULL; 1692 } 1693 } 1694 1695 /* initialize for readdir in lower */ 1696 if (unsp->uns_readdir_status == 1) { 1697 unsp->uns_readdir_status = 2; 1698 /* 1699 * Backup uio_offset. See the comment after the 1700 * VOP_READDIR call on the lower layer. 1701 */ 1702 uio_offset_bk = uio->uio_offset; 1703 uio->uio_offset = 0; 1704 } 1705 1706 if (lvp == NULLVP) { 1707 error = EBADF; 1708 goto unionfs_readdir_exit; 1709 } 1710 /* read lower */ 1711 error = VOP_READDIR(lvp, uio, ap->a_cred, ap->a_eofflag, 1712 ap->a_ncookies, ap->a_cookies); 1713 1714 /* 1715 * We can't return an uio_offset of 0: this would trigger an 1716 * infinite loop, because the next call to unionfs_readdir would 1717 * always restart with the upper layer (uio_offset == 0) and 1718 * always return some data. 1719 * 1720 * This happens when the lower layer root directory is removed. 1721 * (A root directory deleting of unionfs should not be permitted. 1722 * But current VFS can not do it.) 1723 */ 1724 if (uio->uio_offset == 0) 1725 uio->uio_offset = uio_offset_bk; 1726 1727 if (cookies_bk != NULL) { 1728 /* merge cookies */ 1729 int size; 1730 uint64_t *newcookies, *pos; 1731 1732 size = *(ap->a_ncookies) + ncookies_bk; 1733 newcookies = (uint64_t *) malloc(size * sizeof(*newcookies), 1734 M_TEMP, M_WAITOK); 1735 pos = newcookies; 1736 1737 memcpy(pos, cookies_bk, ncookies_bk * sizeof(*newcookies)); 1738 pos += ncookies_bk; 1739 memcpy(pos, *(ap->a_cookies), 1740 *(ap->a_ncookies) * sizeof(*newcookies)); 1741 free(cookies_bk, M_TEMP); 1742 free(*(ap->a_cookies), M_TEMP); 1743 *(ap->a_ncookies) = size; 1744 *(ap->a_cookies) = newcookies; 1745 } 1746 1747 unionfs_readdir_exit: 1748 if (error != 0 && ap->a_eofflag != NULL) 1749 *(ap->a_eofflag) = 1; 1750 1751 UNIONFS_INTERNAL_DEBUG("unionfs_readdir: leave (%d)\n", error); 1752 1753 return (error); 1754 } 1755 1756 static int 1757 unionfs_readlink(struct vop_readlink_args *ap) 1758 { 1759 struct unionfs_node *unp; 1760 struct vnode *vp; 1761 int error; 1762 1763 UNIONFS_INTERNAL_DEBUG("unionfs_readlink: enter\n"); 1764 1765 KASSERT_UNIONFS_VNODE(ap->a_vp); 1766 1767 unp = VTOUNIONFS(ap->a_vp); 1768 vp = (unp->un_uppervp != NULLVP ? unp->un_uppervp : unp->un_lowervp); 1769 1770 error = VOP_READLINK(vp, ap->a_uio, ap->a_cred); 1771 1772 UNIONFS_INTERNAL_DEBUG("unionfs_readlink: leave (%d)\n", error); 1773 1774 return (error); 1775 } 1776 1777 static int 1778 unionfs_getwritemount(struct vop_getwritemount_args *ap) 1779 { 1780 struct unionfs_node *unp; 1781 struct vnode *uvp; 1782 struct vnode *vp, *ovp; 1783 int error; 1784 1785 UNIONFS_INTERNAL_DEBUG("unionfs_getwritemount: enter\n"); 1786 1787 error = 0; 1788 vp = ap->a_vp; 1789 uvp = NULLVP; 1790 1791 VI_LOCK(vp); 1792 unp = VTOUNIONFS(vp); 1793 if (unp != NULL) 1794 uvp = unp->un_uppervp; 1795 1796 /* 1797 * If our node has no upper vnode, check the parent directory. 1798 * We may be initiating a write operation that will produce a 1799 * new upper vnode through CoW. 1800 */ 1801 if (uvp == NULLVP && unp != NULL) { 1802 ovp = vp; 1803 vp = unp->un_dvp; 1804 /* 1805 * Only the root vnode should have an empty parent, but it 1806 * should not have an empty uppervp, so we shouldn't get here. 1807 */ 1808 VNASSERT(vp != NULL, ovp, ("%s: NULL parent vnode", __func__)); 1809 VI_UNLOCK(ovp); 1810 VI_LOCK(vp); 1811 unp = VTOUNIONFS(vp); 1812 if (unp != NULL) 1813 uvp = unp->un_uppervp; 1814 if (uvp == NULLVP) 1815 error = EACCES; 1816 } 1817 1818 if (uvp != NULLVP) { 1819 vholdnz(uvp); 1820 VI_UNLOCK(vp); 1821 error = VOP_GETWRITEMOUNT(uvp, ap->a_mpp); 1822 vdrop(uvp); 1823 } else { 1824 VI_UNLOCK(vp); 1825 *(ap->a_mpp) = NULL; 1826 } 1827 1828 UNIONFS_INTERNAL_DEBUG("unionfs_getwritemount: leave (%d)\n", error); 1829 1830 return (error); 1831 } 1832 1833 static int 1834 unionfs_inactive(struct vop_inactive_args *ap) 1835 { 1836 ap->a_vp->v_object = NULL; 1837 vrecycle(ap->a_vp); 1838 return (0); 1839 } 1840 1841 static int 1842 unionfs_reclaim(struct vop_reclaim_args *ap) 1843 { 1844 /* UNIONFS_INTERNAL_DEBUG("unionfs_reclaim: enter\n"); */ 1845 1846 unionfs_noderem(ap->a_vp); 1847 1848 /* UNIONFS_INTERNAL_DEBUG("unionfs_reclaim: leave\n"); */ 1849 1850 return (0); 1851 } 1852 1853 static int 1854 unionfs_print(struct vop_print_args *ap) 1855 { 1856 struct unionfs_node *unp; 1857 /* struct unionfs_node_status *unsp; */ 1858 1859 unp = VTOUNIONFS(ap->a_vp); 1860 /* unionfs_get_node_status(unp, curthread, &unsp); */ 1861 1862 printf("unionfs_vp=%p, uppervp=%p, lowervp=%p\n", 1863 ap->a_vp, unp->un_uppervp, unp->un_lowervp); 1864 /* 1865 printf("unionfs opencnt: uppervp=%d, lowervp=%d\n", 1866 unsp->uns_upper_opencnt, unsp->uns_lower_opencnt); 1867 */ 1868 1869 if (unp->un_uppervp != NULLVP) 1870 vn_printf(unp->un_uppervp, "unionfs: upper "); 1871 if (unp->un_lowervp != NULLVP) 1872 vn_printf(unp->un_lowervp, "unionfs: lower "); 1873 1874 return (0); 1875 } 1876 1877 static int 1878 unionfs_get_llt_revlock(struct vnode *vp, int flags) 1879 { 1880 int revlock; 1881 1882 revlock = 0; 1883 1884 switch (flags & LK_TYPE_MASK) { 1885 case LK_SHARED: 1886 if (VOP_ISLOCKED(vp) == LK_EXCLUSIVE) 1887 revlock = LK_UPGRADE; 1888 else 1889 revlock = LK_RELEASE; 1890 break; 1891 case LK_EXCLUSIVE: 1892 case LK_UPGRADE: 1893 revlock = LK_RELEASE; 1894 break; 1895 case LK_DOWNGRADE: 1896 revlock = LK_UPGRADE; 1897 break; 1898 default: 1899 break; 1900 } 1901 1902 return (revlock); 1903 } 1904 1905 /* 1906 * The state of an acquired lock is adjusted similarly to 1907 * the time of error generating. 1908 * flags: LK_RELEASE or LK_UPGRADE 1909 */ 1910 static void 1911 unionfs_revlock(struct vnode *vp, int flags) 1912 { 1913 if (flags & LK_RELEASE) 1914 VOP_UNLOCK_FLAGS(vp, flags); 1915 else { 1916 /* UPGRADE */ 1917 if (vn_lock(vp, flags) != 0) 1918 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 1919 } 1920 } 1921 1922 static int 1923 unionfs_lock(struct vop_lock1_args *ap) 1924 { 1925 struct unionfs_node *unp; 1926 struct vnode *vp; 1927 struct vnode *uvp; 1928 struct vnode *lvp; 1929 int error; 1930 int flags; 1931 int revlock; 1932 int interlock; 1933 int uhold; 1934 1935 /* 1936 * TODO: rework the unionfs locking scheme. 1937 * It's not guaranteed to be safe to blindly lock two vnodes on 1938 * different mounts as is done here. Further, the entanglement 1939 * of locking both vnodes with the various options that can be 1940 * passed to VOP_LOCK() makes this code hard to reason about. 1941 * Instead, consider locking only the upper vnode, or the lower 1942 * vnode is the upper is not present, and taking separate measures 1943 * to lock both vnodes in the few cases when that is needed. 1944 */ 1945 error = 0; 1946 interlock = 1; 1947 uhold = 0; 1948 flags = ap->a_flags; 1949 vp = ap->a_vp; 1950 1951 if (LK_RELEASE == (flags & LK_TYPE_MASK) || !(flags & LK_TYPE_MASK)) 1952 return (VOP_UNLOCK_FLAGS(vp, flags | LK_RELEASE)); 1953 1954 if ((flags & LK_INTERLOCK) == 0) 1955 VI_LOCK(vp); 1956 1957 unp = VTOUNIONFS(vp); 1958 if (unp == NULL) 1959 goto unionfs_lock_null_vnode; 1960 1961 KASSERT_UNIONFS_VNODE(ap->a_vp); 1962 1963 lvp = unp->un_lowervp; 1964 uvp = unp->un_uppervp; 1965 1966 if ((revlock = unionfs_get_llt_revlock(vp, flags)) == 0) 1967 panic("unknown lock type: 0x%x", flags & LK_TYPE_MASK); 1968 1969 /* 1970 * During unmount, the root vnode lock may be taken recursively, 1971 * because it may share the same v_vnlock field as the vnode covered by 1972 * the unionfs mount. The covered vnode is locked across VFS_UNMOUNT(), 1973 * and the same lock may be taken recursively here during vflush() 1974 * issued by unionfs_unmount(). 1975 */ 1976 if ((flags & LK_TYPE_MASK) == LK_EXCLUSIVE && 1977 (vp->v_vflag & VV_ROOT) != 0) 1978 flags |= LK_CANRECURSE; 1979 1980 if (lvp != NULLVP) { 1981 if (uvp != NULLVP && flags & LK_UPGRADE) { 1982 /* 1983 * Share Lock is once released and a deadlock is 1984 * avoided. 1985 */ 1986 vholdnz(uvp); 1987 uhold = 1; 1988 VOP_UNLOCK(uvp); 1989 } 1990 VI_LOCK_FLAGS(lvp, MTX_DUPOK); 1991 flags |= LK_INTERLOCK; 1992 vholdl(lvp); 1993 1994 VI_UNLOCK(vp); 1995 ap->a_flags &= ~LK_INTERLOCK; 1996 1997 error = VOP_LOCK(lvp, flags); 1998 1999 VI_LOCK(vp); 2000 unp = VTOUNIONFS(vp); 2001 if (unp == NULL) { 2002 /* vnode is released. */ 2003 VI_UNLOCK(vp); 2004 if (error == 0) 2005 VOP_UNLOCK(lvp); 2006 vdrop(lvp); 2007 if (uhold != 0) 2008 vdrop(uvp); 2009 goto unionfs_lock_fallback; 2010 } 2011 } 2012 2013 if (error == 0 && uvp != NULLVP) { 2014 if (uhold && flags & LK_UPGRADE) { 2015 flags &= ~LK_TYPE_MASK; 2016 flags |= LK_EXCLUSIVE; 2017 } 2018 VI_LOCK_FLAGS(uvp, MTX_DUPOK); 2019 flags |= LK_INTERLOCK; 2020 if (uhold == 0) { 2021 vholdl(uvp); 2022 uhold = 1; 2023 } 2024 2025 VI_UNLOCK(vp); 2026 ap->a_flags &= ~LK_INTERLOCK; 2027 2028 error = VOP_LOCK(uvp, flags); 2029 2030 VI_LOCK(vp); 2031 unp = VTOUNIONFS(vp); 2032 if (unp == NULL) { 2033 /* vnode is released. */ 2034 VI_UNLOCK(vp); 2035 if (error == 0) 2036 VOP_UNLOCK(uvp); 2037 vdrop(uvp); 2038 if (lvp != NULLVP) { 2039 VOP_UNLOCK(lvp); 2040 vdrop(lvp); 2041 } 2042 goto unionfs_lock_fallback; 2043 } 2044 if (error != 0 && lvp != NULLVP) { 2045 /* rollback */ 2046 VI_UNLOCK(vp); 2047 unionfs_revlock(lvp, revlock); 2048 interlock = 0; 2049 } 2050 } 2051 2052 if (interlock) 2053 VI_UNLOCK(vp); 2054 if (lvp != NULLVP) 2055 vdrop(lvp); 2056 if (uhold != 0) 2057 vdrop(uvp); 2058 2059 return (error); 2060 2061 unionfs_lock_null_vnode: 2062 ap->a_flags |= LK_INTERLOCK; 2063 return (vop_stdlock(ap)); 2064 2065 unionfs_lock_fallback: 2066 /* 2067 * If we reach this point, we've discovered the unionfs vnode 2068 * has been reclaimed while the upper/lower vnode locks were 2069 * temporarily dropped. Such temporary droppage may happen 2070 * during the course of an LK_UPGRADE operation itself, and in 2071 * that case LK_UPGRADE must be cleared as the unionfs vnode's 2072 * lock has been reset to point to the standard v_lock field, 2073 * which has not previously been held. 2074 */ 2075 if (flags & LK_UPGRADE) { 2076 ap->a_flags &= ~LK_TYPE_MASK; 2077 ap->a_flags |= LK_EXCLUSIVE; 2078 } 2079 return (vop_stdlock(ap)); 2080 } 2081 2082 static int 2083 unionfs_unlock(struct vop_unlock_args *ap) 2084 { 2085 struct vnode *vp; 2086 struct vnode *lvp; 2087 struct vnode *uvp; 2088 struct unionfs_node *unp; 2089 int error; 2090 int uhold; 2091 2092 KASSERT_UNIONFS_VNODE(ap->a_vp); 2093 2094 error = 0; 2095 uhold = 0; 2096 vp = ap->a_vp; 2097 2098 unp = VTOUNIONFS(vp); 2099 if (unp == NULL) 2100 goto unionfs_unlock_null_vnode; 2101 lvp = unp->un_lowervp; 2102 uvp = unp->un_uppervp; 2103 2104 if (lvp != NULLVP) { 2105 vholdnz(lvp); 2106 error = VOP_UNLOCK(lvp); 2107 } 2108 2109 if (error == 0 && uvp != NULLVP) { 2110 vholdnz(uvp); 2111 uhold = 1; 2112 error = VOP_UNLOCK(uvp); 2113 } 2114 2115 if (lvp != NULLVP) 2116 vdrop(lvp); 2117 if (uhold != 0) 2118 vdrop(uvp); 2119 2120 return error; 2121 2122 unionfs_unlock_null_vnode: 2123 return (vop_stdunlock(ap)); 2124 } 2125 2126 static int 2127 unionfs_pathconf(struct vop_pathconf_args *ap) 2128 { 2129 struct unionfs_node *unp; 2130 struct vnode *vp; 2131 2132 KASSERT_UNIONFS_VNODE(ap->a_vp); 2133 2134 unp = VTOUNIONFS(ap->a_vp); 2135 vp = (unp->un_uppervp != NULLVP ? unp->un_uppervp : unp->un_lowervp); 2136 2137 return (VOP_PATHCONF(vp, ap->a_name, ap->a_retval)); 2138 } 2139 2140 static int 2141 unionfs_advlock(struct vop_advlock_args *ap) 2142 { 2143 struct unionfs_node *unp; 2144 struct unionfs_node_status *unsp; 2145 struct vnode *vp; 2146 struct vnode *uvp; 2147 struct thread *td; 2148 int error; 2149 2150 UNIONFS_INTERNAL_DEBUG("unionfs_advlock: enter\n"); 2151 2152 KASSERT_UNIONFS_VNODE(ap->a_vp); 2153 2154 vp = ap->a_vp; 2155 td = curthread; 2156 2157 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 2158 2159 unp = VTOUNIONFS(ap->a_vp); 2160 uvp = unp->un_uppervp; 2161 2162 if (uvp == NULLVP) { 2163 error = unionfs_copyfile(unp, 1, td->td_ucred, td); 2164 if (error != 0) 2165 goto unionfs_advlock_abort; 2166 uvp = unp->un_uppervp; 2167 2168 unionfs_get_node_status(unp, td, &unsp); 2169 if (unsp->uns_lower_opencnt > 0) { 2170 /* try reopen the vnode */ 2171 error = VOP_OPEN(uvp, unsp->uns_lower_openmode, 2172 td->td_ucred, td, NULL); 2173 if (error) 2174 goto unionfs_advlock_abort; 2175 unsp->uns_upper_opencnt++; 2176 VOP_CLOSE(unp->un_lowervp, unsp->uns_lower_openmode, 2177 td->td_ucred, td); 2178 unsp->uns_lower_opencnt--; 2179 } else 2180 unionfs_tryrem_node_status(unp, unsp); 2181 } 2182 2183 VOP_UNLOCK(vp); 2184 2185 error = VOP_ADVLOCK(uvp, ap->a_id, ap->a_op, ap->a_fl, ap->a_flags); 2186 2187 UNIONFS_INTERNAL_DEBUG("unionfs_advlock: leave (%d)\n", error); 2188 2189 return error; 2190 2191 unionfs_advlock_abort: 2192 VOP_UNLOCK(vp); 2193 2194 UNIONFS_INTERNAL_DEBUG("unionfs_advlock: leave (%d)\n", error); 2195 2196 return error; 2197 } 2198 2199 static int 2200 unionfs_strategy(struct vop_strategy_args *ap) 2201 { 2202 struct unionfs_node *unp; 2203 struct vnode *vp; 2204 2205 KASSERT_UNIONFS_VNODE(ap->a_vp); 2206 2207 unp = VTOUNIONFS(ap->a_vp); 2208 vp = (unp->un_uppervp != NULLVP ? unp->un_uppervp : unp->un_lowervp); 2209 2210 #ifdef DIAGNOSTIC 2211 if (vp == NULLVP) 2212 panic("unionfs_strategy: nullvp"); 2213 2214 if (ap->a_bp->b_iocmd == BIO_WRITE && vp == unp->un_lowervp) 2215 panic("unionfs_strategy: writing to lowervp"); 2216 #endif 2217 2218 return (VOP_STRATEGY(vp, ap->a_bp)); 2219 } 2220 2221 static int 2222 unionfs_getacl(struct vop_getacl_args *ap) 2223 { 2224 struct unionfs_node *unp; 2225 struct vnode *vp; 2226 int error; 2227 2228 KASSERT_UNIONFS_VNODE(ap->a_vp); 2229 2230 unp = VTOUNIONFS(ap->a_vp); 2231 vp = (unp->un_uppervp != NULLVP ? unp->un_uppervp : unp->un_lowervp); 2232 2233 UNIONFS_INTERNAL_DEBUG("unionfs_getacl: enter\n"); 2234 2235 error = VOP_GETACL(vp, ap->a_type, ap->a_aclp, ap->a_cred, ap->a_td); 2236 2237 UNIONFS_INTERNAL_DEBUG("unionfs_getacl: leave (%d)\n", error); 2238 2239 return (error); 2240 } 2241 2242 static int 2243 unionfs_setacl(struct vop_setacl_args *ap) 2244 { 2245 struct unionfs_node *unp; 2246 struct vnode *uvp; 2247 struct vnode *lvp; 2248 struct thread *td; 2249 int error; 2250 2251 UNIONFS_INTERNAL_DEBUG("unionfs_setacl: enter\n"); 2252 2253 KASSERT_UNIONFS_VNODE(ap->a_vp); 2254 2255 error = EROFS; 2256 unp = VTOUNIONFS(ap->a_vp); 2257 uvp = unp->un_uppervp; 2258 lvp = unp->un_lowervp; 2259 td = ap->a_td; 2260 2261 if (ap->a_vp->v_mount->mnt_flag & MNT_RDONLY) 2262 return (EROFS); 2263 2264 if (uvp == NULLVP && lvp->v_type == VREG) { 2265 if ((error = unionfs_copyfile(unp, 1, ap->a_cred, td)) != 0) 2266 return (error); 2267 uvp = unp->un_uppervp; 2268 } 2269 2270 if (uvp != NULLVP) 2271 error = VOP_SETACL(uvp, ap->a_type, ap->a_aclp, ap->a_cred, td); 2272 2273 UNIONFS_INTERNAL_DEBUG("unionfs_setacl: leave (%d)\n", error); 2274 2275 return (error); 2276 } 2277 2278 static int 2279 unionfs_aclcheck(struct vop_aclcheck_args *ap) 2280 { 2281 struct unionfs_node *unp; 2282 struct vnode *vp; 2283 int error; 2284 2285 UNIONFS_INTERNAL_DEBUG("unionfs_aclcheck: enter\n"); 2286 2287 KASSERT_UNIONFS_VNODE(ap->a_vp); 2288 2289 unp = VTOUNIONFS(ap->a_vp); 2290 vp = (unp->un_uppervp != NULLVP ? unp->un_uppervp : unp->un_lowervp); 2291 2292 error = VOP_ACLCHECK(vp, ap->a_type, ap->a_aclp, ap->a_cred, ap->a_td); 2293 2294 UNIONFS_INTERNAL_DEBUG("unionfs_aclcheck: leave (%d)\n", error); 2295 2296 return (error); 2297 } 2298 2299 static int 2300 unionfs_openextattr(struct vop_openextattr_args *ap) 2301 { 2302 struct unionfs_node *unp; 2303 struct vnode *vp; 2304 struct vnode *tvp; 2305 int error; 2306 2307 KASSERT_UNIONFS_VNODE(ap->a_vp); 2308 2309 vp = ap->a_vp; 2310 unp = VTOUNIONFS(vp); 2311 tvp = (unp->un_uppervp != NULLVP ? unp->un_uppervp : unp->un_lowervp); 2312 2313 if ((tvp == unp->un_uppervp && (unp->un_flag & UNIONFS_OPENEXTU)) || 2314 (tvp == unp->un_lowervp && (unp->un_flag & UNIONFS_OPENEXTL))) 2315 return (EBUSY); 2316 2317 error = VOP_OPENEXTATTR(tvp, ap->a_cred, ap->a_td); 2318 2319 if (error == 0) { 2320 if (vn_lock(vp, LK_UPGRADE) != 0) 2321 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 2322 if (!VN_IS_DOOMED(vp)) { 2323 if (tvp == unp->un_uppervp) 2324 unp->un_flag |= UNIONFS_OPENEXTU; 2325 else 2326 unp->un_flag |= UNIONFS_OPENEXTL; 2327 } 2328 vn_lock(vp, LK_DOWNGRADE | LK_RETRY); 2329 } 2330 2331 return (error); 2332 } 2333 2334 static int 2335 unionfs_closeextattr(struct vop_closeextattr_args *ap) 2336 { 2337 struct unionfs_node *unp; 2338 struct vnode *vp; 2339 struct vnode *tvp; 2340 int error; 2341 2342 KASSERT_UNIONFS_VNODE(ap->a_vp); 2343 2344 vp = ap->a_vp; 2345 unp = VTOUNIONFS(vp); 2346 tvp = NULLVP; 2347 2348 if (unp->un_flag & UNIONFS_OPENEXTU) 2349 tvp = unp->un_uppervp; 2350 else if (unp->un_flag & UNIONFS_OPENEXTL) 2351 tvp = unp->un_lowervp; 2352 2353 if (tvp == NULLVP) 2354 return (EOPNOTSUPP); 2355 2356 error = VOP_CLOSEEXTATTR(tvp, ap->a_commit, ap->a_cred, ap->a_td); 2357 2358 if (error == 0) { 2359 if (vn_lock(vp, LK_UPGRADE) != 0) 2360 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 2361 if (!VN_IS_DOOMED(vp)) { 2362 if (tvp == unp->un_uppervp) 2363 unp->un_flag &= ~UNIONFS_OPENEXTU; 2364 else 2365 unp->un_flag &= ~UNIONFS_OPENEXTL; 2366 } 2367 vn_lock(vp, LK_DOWNGRADE | LK_RETRY); 2368 } 2369 2370 return (error); 2371 } 2372 2373 static int 2374 unionfs_getextattr(struct vop_getextattr_args *ap) 2375 { 2376 struct unionfs_node *unp; 2377 struct vnode *vp; 2378 2379 KASSERT_UNIONFS_VNODE(ap->a_vp); 2380 2381 unp = VTOUNIONFS(ap->a_vp); 2382 vp = NULLVP; 2383 2384 if (unp->un_flag & UNIONFS_OPENEXTU) 2385 vp = unp->un_uppervp; 2386 else if (unp->un_flag & UNIONFS_OPENEXTL) 2387 vp = unp->un_lowervp; 2388 2389 if (vp == NULLVP) 2390 return (EOPNOTSUPP); 2391 2392 return (VOP_GETEXTATTR(vp, ap->a_attrnamespace, ap->a_name, 2393 ap->a_uio, ap->a_size, ap->a_cred, ap->a_td)); 2394 } 2395 2396 static int 2397 unionfs_setextattr(struct vop_setextattr_args *ap) 2398 { 2399 struct unionfs_node *unp; 2400 struct vnode *uvp; 2401 struct vnode *lvp; 2402 struct vnode *ovp; 2403 struct ucred *cred; 2404 struct thread *td; 2405 int error; 2406 2407 KASSERT_UNIONFS_VNODE(ap->a_vp); 2408 2409 error = EROFS; 2410 unp = VTOUNIONFS(ap->a_vp); 2411 uvp = unp->un_uppervp; 2412 lvp = unp->un_lowervp; 2413 ovp = NULLVP; 2414 cred = ap->a_cred; 2415 td = ap->a_td; 2416 2417 UNIONFS_INTERNAL_DEBUG("unionfs_setextattr: enter (un_flag=%x)\n", 2418 unp->un_flag); 2419 2420 if (ap->a_vp->v_mount->mnt_flag & MNT_RDONLY) 2421 return (EROFS); 2422 2423 if (unp->un_flag & UNIONFS_OPENEXTU) 2424 ovp = unp->un_uppervp; 2425 else if (unp->un_flag & UNIONFS_OPENEXTL) 2426 ovp = unp->un_lowervp; 2427 2428 if (ovp == NULLVP) 2429 return (EOPNOTSUPP); 2430 2431 if (ovp == lvp && lvp->v_type == VREG) { 2432 VOP_CLOSEEXTATTR(lvp, 0, cred, td); 2433 if (uvp == NULLVP && 2434 (error = unionfs_copyfile(unp, 1, cred, td)) != 0) { 2435 unionfs_setextattr_reopen: 2436 if ((unp->un_flag & UNIONFS_OPENEXTL) && 2437 VOP_OPENEXTATTR(lvp, cred, td)) { 2438 #ifdef DIAGNOSTIC 2439 panic("unionfs: VOP_OPENEXTATTR failed"); 2440 #endif 2441 unp->un_flag &= ~UNIONFS_OPENEXTL; 2442 } 2443 goto unionfs_setextattr_abort; 2444 } 2445 uvp = unp->un_uppervp; 2446 if ((error = VOP_OPENEXTATTR(uvp, cred, td)) != 0) 2447 goto unionfs_setextattr_reopen; 2448 unp->un_flag &= ~UNIONFS_OPENEXTL; 2449 unp->un_flag |= UNIONFS_OPENEXTU; 2450 ovp = uvp; 2451 } 2452 2453 if (ovp == uvp) 2454 error = VOP_SETEXTATTR(ovp, ap->a_attrnamespace, ap->a_name, 2455 ap->a_uio, cred, td); 2456 2457 unionfs_setextattr_abort: 2458 UNIONFS_INTERNAL_DEBUG("unionfs_setextattr: leave (%d)\n", error); 2459 2460 return (error); 2461 } 2462 2463 static int 2464 unionfs_listextattr(struct vop_listextattr_args *ap) 2465 { 2466 struct unionfs_node *unp; 2467 struct vnode *vp; 2468 2469 KASSERT_UNIONFS_VNODE(ap->a_vp); 2470 2471 unp = VTOUNIONFS(ap->a_vp); 2472 vp = NULLVP; 2473 2474 if (unp->un_flag & UNIONFS_OPENEXTU) 2475 vp = unp->un_uppervp; 2476 else if (unp->un_flag & UNIONFS_OPENEXTL) 2477 vp = unp->un_lowervp; 2478 2479 if (vp == NULLVP) 2480 return (EOPNOTSUPP); 2481 2482 return (VOP_LISTEXTATTR(vp, ap->a_attrnamespace, ap->a_uio, 2483 ap->a_size, ap->a_cred, ap->a_td)); 2484 } 2485 2486 static int 2487 unionfs_deleteextattr(struct vop_deleteextattr_args *ap) 2488 { 2489 struct unionfs_node *unp; 2490 struct vnode *uvp; 2491 struct vnode *lvp; 2492 struct vnode *ovp; 2493 struct ucred *cred; 2494 struct thread *td; 2495 int error; 2496 2497 KASSERT_UNIONFS_VNODE(ap->a_vp); 2498 2499 error = EROFS; 2500 unp = VTOUNIONFS(ap->a_vp); 2501 uvp = unp->un_uppervp; 2502 lvp = unp->un_lowervp; 2503 ovp = NULLVP; 2504 cred = ap->a_cred; 2505 td = ap->a_td; 2506 2507 UNIONFS_INTERNAL_DEBUG("unionfs_deleteextattr: enter (un_flag=%x)\n", 2508 unp->un_flag); 2509 2510 if (ap->a_vp->v_mount->mnt_flag & MNT_RDONLY) 2511 return (EROFS); 2512 2513 if (unp->un_flag & UNIONFS_OPENEXTU) 2514 ovp = unp->un_uppervp; 2515 else if (unp->un_flag & UNIONFS_OPENEXTL) 2516 ovp = unp->un_lowervp; 2517 2518 if (ovp == NULLVP) 2519 return (EOPNOTSUPP); 2520 2521 if (ovp == lvp && lvp->v_type == VREG) { 2522 VOP_CLOSEEXTATTR(lvp, 0, cred, td); 2523 if (uvp == NULLVP && 2524 (error = unionfs_copyfile(unp, 1, cred, td)) != 0) { 2525 unionfs_deleteextattr_reopen: 2526 if ((unp->un_flag & UNIONFS_OPENEXTL) && 2527 VOP_OPENEXTATTR(lvp, cred, td)) { 2528 #ifdef DIAGNOSTIC 2529 panic("unionfs: VOP_OPENEXTATTR failed"); 2530 #endif 2531 unp->un_flag &= ~UNIONFS_OPENEXTL; 2532 } 2533 goto unionfs_deleteextattr_abort; 2534 } 2535 uvp = unp->un_uppervp; 2536 if ((error = VOP_OPENEXTATTR(uvp, cred, td)) != 0) 2537 goto unionfs_deleteextattr_reopen; 2538 unp->un_flag &= ~UNIONFS_OPENEXTL; 2539 unp->un_flag |= UNIONFS_OPENEXTU; 2540 ovp = uvp; 2541 } 2542 2543 if (ovp == uvp) 2544 error = VOP_DELETEEXTATTR(ovp, ap->a_attrnamespace, ap->a_name, 2545 ap->a_cred, ap->a_td); 2546 2547 unionfs_deleteextattr_abort: 2548 UNIONFS_INTERNAL_DEBUG("unionfs_deleteextattr: leave (%d)\n", error); 2549 2550 return (error); 2551 } 2552 2553 static int 2554 unionfs_setlabel(struct vop_setlabel_args *ap) 2555 { 2556 struct unionfs_node *unp; 2557 struct vnode *uvp; 2558 struct vnode *lvp; 2559 struct thread *td; 2560 int error; 2561 2562 UNIONFS_INTERNAL_DEBUG("unionfs_setlabel: enter\n"); 2563 2564 KASSERT_UNIONFS_VNODE(ap->a_vp); 2565 2566 error = EROFS; 2567 unp = VTOUNIONFS(ap->a_vp); 2568 uvp = unp->un_uppervp; 2569 lvp = unp->un_lowervp; 2570 td = ap->a_td; 2571 2572 if (ap->a_vp->v_mount->mnt_flag & MNT_RDONLY) 2573 return (EROFS); 2574 2575 if (uvp == NULLVP && lvp->v_type == VREG) { 2576 if ((error = unionfs_copyfile(unp, 1, ap->a_cred, td)) != 0) 2577 return (error); 2578 uvp = unp->un_uppervp; 2579 } 2580 2581 if (uvp != NULLVP) 2582 error = VOP_SETLABEL(uvp, ap->a_label, ap->a_cred, td); 2583 2584 UNIONFS_INTERNAL_DEBUG("unionfs_setlabel: leave (%d)\n", error); 2585 2586 return (error); 2587 } 2588 2589 static int 2590 unionfs_vptofh(struct vop_vptofh_args *ap) 2591 { 2592 return (EOPNOTSUPP); 2593 } 2594 2595 static int 2596 unionfs_add_writecount(struct vop_add_writecount_args *ap) 2597 { 2598 struct vnode *tvp, *vp; 2599 struct unionfs_node *unp; 2600 int error, writerefs __diagused; 2601 2602 vp = ap->a_vp; 2603 unp = VTOUNIONFS(vp); 2604 tvp = unp->un_uppervp; 2605 KASSERT(tvp != NULL, 2606 ("%s: adding write ref without upper vnode", __func__)); 2607 error = VOP_ADD_WRITECOUNT(tvp, ap->a_inc); 2608 if (error != 0) 2609 return (error); 2610 /* 2611 * We need to track the write refs we've passed to the underlying 2612 * vnodes so that we can undo them in case we are forcibly unmounted. 2613 */ 2614 writerefs = atomic_fetchadd_int(&vp->v_writecount, ap->a_inc); 2615 /* text refs are bypassed to lowervp */ 2616 VNASSERT(writerefs >= 0, vp, 2617 ("%s: invalid write count %d", __func__, writerefs)); 2618 VNASSERT(writerefs + ap->a_inc >= 0, vp, 2619 ("%s: invalid write count inc %d + %d", __func__, 2620 writerefs, ap->a_inc)); 2621 return (0); 2622 } 2623 2624 static int 2625 unionfs_vput_pair(struct vop_vput_pair_args *ap) 2626 { 2627 struct mount *mp; 2628 struct vnode *dvp, *vp, **vpp, *lvp, *ldvp, *uvp, *udvp, *tempvp; 2629 struct unionfs_node *dunp, *unp; 2630 int error, res; 2631 2632 dvp = ap->a_dvp; 2633 vpp = ap->a_vpp; 2634 vp = NULLVP; 2635 lvp = NULLVP; 2636 uvp = NULLVP; 2637 unp = NULL; 2638 2639 dunp = VTOUNIONFS(dvp); 2640 udvp = dunp->un_uppervp; 2641 ldvp = dunp->un_lowervp; 2642 2643 /* 2644 * Underlying vnodes should be locked because the encompassing unionfs 2645 * node is locked, but will not be referenced, as the reference will 2646 * only be on the unionfs node. Reference them now so that the vput()s 2647 * performed by VOP_VPUT_PAIR() will have a reference to drop. 2648 */ 2649 if (udvp != NULLVP) 2650 vref(udvp); 2651 if (ldvp != NULLVP) 2652 vref(ldvp); 2653 2654 if (vpp != NULL) 2655 vp = *vpp; 2656 2657 if (vp != NULLVP) { 2658 unp = VTOUNIONFS(vp); 2659 uvp = unp->un_uppervp; 2660 lvp = unp->un_lowervp; 2661 if (uvp != NULLVP) 2662 vref(uvp); 2663 if (lvp != NULLVP) 2664 vref(lvp); 2665 2666 /* 2667 * If we're being asked to return a locked child vnode, then 2668 * we may need to create a replacement vnode in case the 2669 * original is reclaimed while the lock is dropped. In that 2670 * case we'll need to ensure the mount and the underlying 2671 * vnodes aren't also recycled during that window. 2672 */ 2673 if (!ap->a_unlock_vp) { 2674 vhold(vp); 2675 if (uvp != NULLVP) 2676 vhold(uvp); 2677 if (lvp != NULLVP) 2678 vhold(lvp); 2679 mp = vp->v_mount; 2680 vfs_ref(mp); 2681 } 2682 } 2683 2684 /* 2685 * TODO: Because unionfs_lock() locks both the lower and upper vnodes 2686 * (if available), we must also call VOP_VPUT_PAIR() on both the lower 2687 * and upper parent/child pairs. If unionfs_lock() is reworked to lock 2688 * only a single vnode, this code will need to change to also only 2689 * operate on one vnode pair. 2690 */ 2691 ASSERT_VOP_LOCKED(ldvp, __func__); 2692 ASSERT_VOP_LOCKED(udvp, __func__); 2693 ASSERT_VOP_LOCKED(lvp, __func__); 2694 ASSERT_VOP_LOCKED(uvp, __func__); 2695 2696 KASSERT(lvp == NULLVP || ldvp != NULLVP, 2697 ("%s: NULL ldvp with non-NULL lvp", __func__)); 2698 if (ldvp != NULLVP) 2699 res = VOP_VPUT_PAIR(ldvp, lvp != NULLVP ? &lvp : NULL, true); 2700 KASSERT(uvp == NULLVP || udvp != NULLVP, 2701 ("%s: NULL udvp with non-NULL uvp", __func__)); 2702 if (udvp != NULLVP) 2703 res = VOP_VPUT_PAIR(udvp, uvp != NULLVP ? &uvp : NULL, true); 2704 2705 ASSERT_VOP_UNLOCKED(ldvp, __func__); 2706 ASSERT_VOP_UNLOCKED(udvp, __func__); 2707 ASSERT_VOP_UNLOCKED(lvp, __func__); 2708 ASSERT_VOP_UNLOCKED(uvp, __func__); 2709 2710 /* 2711 * VOP_VPUT_PAIR() dropped the references we added to the underlying 2712 * vnodes, now drop the caller's reference to the unionfs vnodes. 2713 */ 2714 if (vp != NULLVP && ap->a_unlock_vp) 2715 vrele(vp); 2716 vrele(dvp); 2717 2718 if (vp == NULLVP || ap->a_unlock_vp) 2719 return (res); 2720 2721 /* 2722 * We're being asked to return a locked vnode. At this point, the 2723 * underlying vnodes have been unlocked, so vp may have been reclaimed. 2724 */ 2725 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 2726 if (vp->v_data == NULL && vfs_busy(mp, MBF_NOWAIT) == 0) { 2727 vput(vp); 2728 error = unionfs_nodeget(mp, uvp, lvp, dvp, &tempvp, NULL); 2729 if (error == 0) { 2730 vn_lock(tempvp, LK_EXCLUSIVE | LK_RETRY); 2731 *vpp = tempvp; 2732 } else 2733 vget(vp, LK_EXCLUSIVE | LK_RETRY); 2734 vfs_unbusy(mp); 2735 } 2736 if (lvp != NULLVP) 2737 vdrop(lvp); 2738 if (uvp != NULLVP) 2739 vdrop(uvp); 2740 vdrop(vp); 2741 vfs_rel(mp); 2742 2743 return (res); 2744 } 2745 2746 static int 2747 unionfs_set_text(struct vop_set_text_args *ap) 2748 { 2749 struct vnode *tvp; 2750 struct unionfs_node *unp; 2751 int error; 2752 2753 /* 2754 * We assume text refs are managed against lvp/uvp through the 2755 * executable mapping backed by its VM object. We therefore don't 2756 * need to track leased text refs in the case of a forcible unmount. 2757 */ 2758 unp = VTOUNIONFS(ap->a_vp); 2759 ASSERT_VOP_LOCKED(ap->a_vp, __func__); 2760 tvp = unp->un_uppervp != NULL ? unp->un_uppervp : unp->un_lowervp; 2761 error = VOP_SET_TEXT(tvp); 2762 return (error); 2763 } 2764 2765 static int 2766 unionfs_unset_text(struct vop_unset_text_args *ap) 2767 { 2768 struct vnode *tvp; 2769 struct unionfs_node *unp; 2770 2771 ASSERT_VOP_LOCKED(ap->a_vp, __func__); 2772 unp = VTOUNIONFS(ap->a_vp); 2773 tvp = unp->un_uppervp != NULL ? unp->un_uppervp : unp->un_lowervp; 2774 VOP_UNSET_TEXT_CHECKED(tvp); 2775 return (0); 2776 } 2777 2778 struct vop_vector unionfs_vnodeops = { 2779 .vop_default = &default_vnodeops, 2780 2781 .vop_access = unionfs_access, 2782 .vop_aclcheck = unionfs_aclcheck, 2783 .vop_advlock = unionfs_advlock, 2784 .vop_bmap = VOP_EOPNOTSUPP, 2785 .vop_cachedlookup = unionfs_lookup, 2786 .vop_close = unionfs_close, 2787 .vop_closeextattr = unionfs_closeextattr, 2788 .vop_create = unionfs_create, 2789 .vop_deleteextattr = unionfs_deleteextattr, 2790 .vop_fsync = unionfs_fsync, 2791 .vop_getacl = unionfs_getacl, 2792 .vop_getattr = unionfs_getattr, 2793 .vop_getextattr = unionfs_getextattr, 2794 .vop_getwritemount = unionfs_getwritemount, 2795 .vop_inactive = unionfs_inactive, 2796 .vop_need_inactive = vop_stdneed_inactive, 2797 .vop_islocked = vop_stdislocked, 2798 .vop_ioctl = unionfs_ioctl, 2799 .vop_link = unionfs_link, 2800 .vop_listextattr = unionfs_listextattr, 2801 .vop_lock1 = unionfs_lock, 2802 .vop_lookup = vfs_cache_lookup, 2803 .vop_mkdir = unionfs_mkdir, 2804 .vop_mknod = unionfs_mknod, 2805 .vop_open = unionfs_open, 2806 .vop_openextattr = unionfs_openextattr, 2807 .vop_pathconf = unionfs_pathconf, 2808 .vop_poll = unionfs_poll, 2809 .vop_print = unionfs_print, 2810 .vop_read = unionfs_read, 2811 .vop_readdir = unionfs_readdir, 2812 .vop_readlink = unionfs_readlink, 2813 .vop_reclaim = unionfs_reclaim, 2814 .vop_remove = unionfs_remove, 2815 .vop_rename = unionfs_rename, 2816 .vop_rmdir = unionfs_rmdir, 2817 .vop_setacl = unionfs_setacl, 2818 .vop_setattr = unionfs_setattr, 2819 .vop_setextattr = unionfs_setextattr, 2820 .vop_setlabel = unionfs_setlabel, 2821 .vop_strategy = unionfs_strategy, 2822 .vop_symlink = unionfs_symlink, 2823 .vop_unlock = unionfs_unlock, 2824 .vop_whiteout = unionfs_whiteout, 2825 .vop_write = unionfs_write, 2826 .vop_vptofh = unionfs_vptofh, 2827 .vop_add_writecount = unionfs_add_writecount, 2828 .vop_vput_pair = unionfs_vput_pair, 2829 .vop_set_text = unionfs_set_text, 2830 .vop_unset_text = unionfs_unset_text, 2831 }; 2832 VFS_VOP_VECTOR_REGISTER(unionfs_vnodeops); 2833