1 /* $NetBSD: tmpfs_vnops.c,v 1.39 2007/07/23 15:41:01 jmmv Exp $ */ 2 3 /*- 4 * SPDX-License-Identifier: BSD-2-Clause-NetBSD 5 * 6 * Copyright (c) 2005, 2006 The NetBSD Foundation, Inc. 7 * All rights reserved. 8 * 9 * This code is derived from software contributed to The NetBSD Foundation 10 * by Julio M. Merino Vidal, developed as part of Google's Summer of Code 11 * 2005 program. 12 * 13 * Redistribution and use in source and binary forms, with or without 14 * modification, are permitted provided that the following conditions 15 * are met: 16 * 1. Redistributions of source code must retain the above copyright 17 * notice, this list of conditions and the following disclaimer. 18 * 2. Redistributions in binary form must reproduce the above copyright 19 * notice, this list of conditions and the following disclaimer in the 20 * documentation and/or other materials provided with the distribution. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 23 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 24 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 25 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 26 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 27 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 28 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 29 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 30 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 31 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 32 * POSSIBILITY OF SUCH DAMAGE. 33 */ 34 35 /* 36 * tmpfs vnode interface. 37 */ 38 #include <sys/cdefs.h> 39 __FBSDID("$FreeBSD$"); 40 41 #include <sys/param.h> 42 #include <sys/systm.h> 43 #include <sys/dirent.h> 44 #include <sys/fcntl.h> 45 #include <sys/file.h> 46 #include <sys/limits.h> 47 #include <sys/lockf.h> 48 #include <sys/lock.h> 49 #include <sys/mount.h> 50 #include <sys/namei.h> 51 #include <sys/priv.h> 52 #include <sys/proc.h> 53 #include <sys/rwlock.h> 54 #include <sys/sched.h> 55 #include <sys/stat.h> 56 #include <sys/sysctl.h> 57 #include <sys/unistd.h> 58 #include <sys/vnode.h> 59 #include <sys/smr.h> 60 #include <security/audit/audit.h> 61 #include <security/mac/mac_framework.h> 62 63 #include <vm/vm.h> 64 #include <vm/vm_param.h> 65 #include <vm/vm_object.h> 66 67 #include <fs/tmpfs/tmpfs_vnops.h> 68 #include <fs/tmpfs/tmpfs.h> 69 70 SYSCTL_DECL(_vfs_tmpfs); 71 VFS_SMR_DECLARE; 72 73 static volatile int tmpfs_rename_restarts; 74 SYSCTL_INT(_vfs_tmpfs, OID_AUTO, rename_restarts, CTLFLAG_RD, 75 __DEVOLATILE(int *, &tmpfs_rename_restarts), 0, 76 "Times rename had to restart due to lock contention"); 77 78 static int 79 tmpfs_vn_get_ino_alloc(struct mount *mp, void *arg, int lkflags, 80 struct vnode **rvp) 81 { 82 83 return (tmpfs_alloc_vp(mp, arg, lkflags, rvp)); 84 } 85 86 static int 87 tmpfs_lookup1(struct vnode *dvp, struct vnode **vpp, struct componentname *cnp) 88 { 89 struct tmpfs_dirent *de; 90 struct tmpfs_node *dnode, *pnode; 91 struct tmpfs_mount *tm; 92 int error; 93 94 /* Caller assumes responsibility for ensuring access (VEXEC). */ 95 dnode = VP_TO_TMPFS_DIR(dvp); 96 *vpp = NULLVP; 97 98 /* We cannot be requesting the parent directory of the root node. */ 99 MPASS(IMPLIES(dnode->tn_type == VDIR && 100 dnode->tn_dir.tn_parent == dnode, 101 !(cnp->cn_flags & ISDOTDOT))); 102 103 TMPFS_ASSERT_LOCKED(dnode); 104 if (dnode->tn_dir.tn_parent == NULL) { 105 error = ENOENT; 106 goto out; 107 } 108 if (cnp->cn_flags & ISDOTDOT) { 109 tm = VFS_TO_TMPFS(dvp->v_mount); 110 pnode = dnode->tn_dir.tn_parent; 111 tmpfs_ref_node(pnode); 112 error = vn_vget_ino_gen(dvp, tmpfs_vn_get_ino_alloc, 113 pnode, cnp->cn_lkflags, vpp); 114 tmpfs_free_node(tm, pnode); 115 if (error != 0) 116 goto out; 117 } else if (cnp->cn_namelen == 1 && cnp->cn_nameptr[0] == '.') { 118 VREF(dvp); 119 *vpp = dvp; 120 error = 0; 121 } else { 122 de = tmpfs_dir_lookup(dnode, NULL, cnp); 123 if (de != NULL && de->td_node == NULL) 124 cnp->cn_flags |= ISWHITEOUT; 125 if (de == NULL || de->td_node == NULL) { 126 /* 127 * The entry was not found in the directory. 128 * This is OK if we are creating or renaming an 129 * entry and are working on the last component of 130 * the path name. 131 */ 132 if ((cnp->cn_flags & ISLASTCN) && 133 (cnp->cn_nameiop == CREATE || \ 134 cnp->cn_nameiop == RENAME || 135 (cnp->cn_nameiop == DELETE && 136 cnp->cn_flags & DOWHITEOUT && 137 cnp->cn_flags & ISWHITEOUT))) { 138 error = VOP_ACCESS(dvp, VWRITE, cnp->cn_cred, 139 cnp->cn_thread); 140 if (error != 0) 141 goto out; 142 143 /* 144 * Keep the component name in the buffer for 145 * future uses. 146 */ 147 cnp->cn_flags |= SAVENAME; 148 149 error = EJUSTRETURN; 150 } else 151 error = ENOENT; 152 } else { 153 struct tmpfs_node *tnode; 154 155 /* 156 * The entry was found, so get its associated 157 * tmpfs_node. 158 */ 159 tnode = de->td_node; 160 161 /* 162 * If we are not at the last path component and 163 * found a non-directory or non-link entry (which 164 * may itself be pointing to a directory), raise 165 * an error. 166 */ 167 if ((tnode->tn_type != VDIR && 168 tnode->tn_type != VLNK) && 169 !(cnp->cn_flags & ISLASTCN)) { 170 error = ENOTDIR; 171 goto out; 172 } 173 174 /* 175 * If we are deleting or renaming the entry, keep 176 * track of its tmpfs_dirent so that it can be 177 * easily deleted later. 178 */ 179 if ((cnp->cn_flags & ISLASTCN) && 180 (cnp->cn_nameiop == DELETE || 181 cnp->cn_nameiop == RENAME)) { 182 error = VOP_ACCESS(dvp, VWRITE, cnp->cn_cred, 183 cnp->cn_thread); 184 if (error != 0) 185 goto out; 186 187 /* Allocate a new vnode on the matching entry. */ 188 error = tmpfs_alloc_vp(dvp->v_mount, tnode, 189 cnp->cn_lkflags, vpp); 190 if (error != 0) 191 goto out; 192 193 if ((dnode->tn_mode & S_ISTXT) && 194 VOP_ACCESS(dvp, VADMIN, cnp->cn_cred, 195 cnp->cn_thread) && VOP_ACCESS(*vpp, VADMIN, 196 cnp->cn_cred, cnp->cn_thread)) { 197 error = EPERM; 198 vput(*vpp); 199 *vpp = NULL; 200 goto out; 201 } 202 cnp->cn_flags |= SAVENAME; 203 } else { 204 error = tmpfs_alloc_vp(dvp->v_mount, tnode, 205 cnp->cn_lkflags, vpp); 206 if (error != 0) 207 goto out; 208 } 209 } 210 } 211 212 /* 213 * Store the result of this lookup in the cache. Avoid this if the 214 * request was for creation, as it does not improve timings on 215 * emprical tests. 216 */ 217 if ((cnp->cn_flags & MAKEENTRY) != 0 && tmpfs_use_nc(dvp)) 218 cache_enter(dvp, *vpp, cnp); 219 220 out: 221 /* 222 * If there were no errors, *vpp cannot be null and it must be 223 * locked. 224 */ 225 MPASS(IFF(error == 0, *vpp != NULLVP && VOP_ISLOCKED(*vpp))); 226 227 return (error); 228 } 229 230 static int 231 tmpfs_cached_lookup(struct vop_cachedlookup_args *v) 232 { 233 234 return (tmpfs_lookup1(v->a_dvp, v->a_vpp, v->a_cnp)); 235 } 236 237 static int 238 tmpfs_lookup(struct vop_lookup_args *v) 239 { 240 struct vnode *dvp = v->a_dvp; 241 struct vnode **vpp = v->a_vpp; 242 struct componentname *cnp = v->a_cnp; 243 int error; 244 245 /* Check accessibility of requested node as a first step. */ 246 error = vn_dir_check_exec(dvp, cnp); 247 if (error != 0) 248 return (error); 249 250 return (tmpfs_lookup1(dvp, vpp, cnp)); 251 } 252 253 static int 254 tmpfs_create(struct vop_create_args *v) 255 { 256 struct vnode *dvp = v->a_dvp; 257 struct vnode **vpp = v->a_vpp; 258 struct componentname *cnp = v->a_cnp; 259 struct vattr *vap = v->a_vap; 260 int error; 261 262 MPASS(vap->va_type == VREG || vap->va_type == VSOCK); 263 264 error = tmpfs_alloc_file(dvp, vpp, vap, cnp, NULL); 265 if (error == 0 && (cnp->cn_flags & MAKEENTRY) != 0 && tmpfs_use_nc(dvp)) 266 cache_enter(dvp, *vpp, cnp); 267 return (error); 268 } 269 270 static int 271 tmpfs_mknod(struct vop_mknod_args *v) 272 { 273 struct vnode *dvp = v->a_dvp; 274 struct vnode **vpp = v->a_vpp; 275 struct componentname *cnp = v->a_cnp; 276 struct vattr *vap = v->a_vap; 277 278 if (vap->va_type != VBLK && vap->va_type != VCHR && 279 vap->va_type != VFIFO) 280 return EINVAL; 281 282 return tmpfs_alloc_file(dvp, vpp, vap, cnp, NULL); 283 } 284 285 struct fileops tmpfs_fnops; 286 287 static int 288 tmpfs_open(struct vop_open_args *v) 289 { 290 struct vnode *vp; 291 struct tmpfs_node *node; 292 struct file *fp; 293 int error, mode; 294 295 vp = v->a_vp; 296 mode = v->a_mode; 297 node = VP_TO_TMPFS_NODE(vp); 298 299 /* 300 * The file is still active but all its names have been removed 301 * (e.g. by a "rmdir $(pwd)"). It cannot be opened any more as 302 * it is about to die. 303 */ 304 if (node->tn_links < 1) 305 return (ENOENT); 306 307 /* If the file is marked append-only, deny write requests. */ 308 if (node->tn_flags & APPEND && (mode & (FWRITE | O_APPEND)) == FWRITE) 309 error = EPERM; 310 else { 311 error = 0; 312 /* For regular files, the call below is nop. */ 313 KASSERT(vp->v_type != VREG || (node->tn_reg.tn_aobj->flags & 314 OBJ_DEAD) == 0, ("dead object")); 315 vnode_create_vobject(vp, node->tn_size, v->a_td); 316 } 317 318 fp = v->a_fp; 319 MPASS(fp == NULL || fp->f_data == NULL); 320 if (error == 0 && fp != NULL && vp->v_type == VREG) { 321 tmpfs_ref_node(node); 322 finit_vnode(fp, mode, node, &tmpfs_fnops); 323 } 324 325 return (error); 326 } 327 328 static int 329 tmpfs_close(struct vop_close_args *v) 330 { 331 struct vnode *vp = v->a_vp; 332 333 /* Update node times. */ 334 tmpfs_update(vp); 335 336 return (0); 337 } 338 339 int 340 tmpfs_fo_close(struct file *fp, struct thread *td) 341 { 342 struct tmpfs_node *node; 343 344 node = fp->f_data; 345 if (node != NULL) { 346 MPASS(node->tn_type == VREG); 347 tmpfs_free_node(node->tn_reg.tn_tmp, node); 348 } 349 return (vnops.fo_close(fp, td)); 350 } 351 352 /* 353 * VOP_FPLOOKUP_VEXEC routines are subject to special circumstances, see 354 * the comment above cache_fplookup for details. 355 */ 356 int 357 tmpfs_fplookup_vexec(struct vop_fplookup_vexec_args *v) 358 { 359 struct vnode *vp; 360 struct tmpfs_node *node; 361 struct ucred *cred; 362 mode_t all_x, mode; 363 364 vp = v->a_vp; 365 node = VP_TO_TMPFS_NODE_SMR(vp); 366 if (__predict_false(node == NULL)) 367 return (EAGAIN); 368 369 all_x = S_IXUSR | S_IXGRP | S_IXOTH; 370 mode = atomic_load_short(&node->tn_mode); 371 if (__predict_true((mode & all_x) == all_x)) 372 return (0); 373 374 cred = v->a_cred; 375 return (vaccess_vexec_smr(mode, node->tn_uid, node->tn_gid, cred)); 376 } 377 378 int 379 tmpfs_access(struct vop_access_args *v) 380 { 381 struct vnode *vp = v->a_vp; 382 accmode_t accmode = v->a_accmode; 383 struct ucred *cred = v->a_cred; 384 mode_t all_x = S_IXUSR | S_IXGRP | S_IXOTH; 385 int error; 386 struct tmpfs_node *node; 387 388 MPASS(VOP_ISLOCKED(vp)); 389 390 node = VP_TO_TMPFS_NODE(vp); 391 392 /* 393 * Common case path lookup. 394 */ 395 if (__predict_true(accmode == VEXEC && (node->tn_mode & all_x) == all_x)) 396 return (0); 397 398 switch (vp->v_type) { 399 case VDIR: 400 /* FALLTHROUGH */ 401 case VLNK: 402 /* FALLTHROUGH */ 403 case VREG: 404 if (accmode & VWRITE && vp->v_mount->mnt_flag & MNT_RDONLY) { 405 error = EROFS; 406 goto out; 407 } 408 break; 409 410 case VBLK: 411 /* FALLTHROUGH */ 412 case VCHR: 413 /* FALLTHROUGH */ 414 case VSOCK: 415 /* FALLTHROUGH */ 416 case VFIFO: 417 break; 418 419 default: 420 error = EINVAL; 421 goto out; 422 } 423 424 if (accmode & VWRITE && node->tn_flags & IMMUTABLE) { 425 error = EPERM; 426 goto out; 427 } 428 429 error = vaccess(vp->v_type, node->tn_mode, node->tn_uid, node->tn_gid, 430 accmode, cred); 431 432 out: 433 MPASS(VOP_ISLOCKED(vp)); 434 435 return (error); 436 } 437 438 int 439 tmpfs_stat(struct vop_stat_args *v) 440 { 441 struct vnode *vp = v->a_vp; 442 struct stat *sb = v->a_sb; 443 vm_object_t obj; 444 struct tmpfs_node *node; 445 int error; 446 447 node = VP_TO_TMPFS_NODE(vp); 448 449 tmpfs_update_getattr(vp); 450 451 error = vop_stat_helper_pre(v); 452 if (__predict_false(error)) 453 return (error); 454 455 sb->st_dev = vp->v_mount->mnt_stat.f_fsid.val[0]; 456 sb->st_ino = node->tn_id; 457 sb->st_mode = node->tn_mode | VTTOIF(vp->v_type); 458 sb->st_nlink = node->tn_links; 459 sb->st_uid = node->tn_uid; 460 sb->st_gid = node->tn_gid; 461 sb->st_rdev = (vp->v_type == VBLK || vp->v_type == VCHR) ? 462 node->tn_rdev : NODEV; 463 sb->st_size = node->tn_size; 464 sb->st_atim.tv_sec = node->tn_atime.tv_sec; 465 sb->st_atim.tv_nsec = node->tn_atime.tv_nsec; 466 sb->st_mtim.tv_sec = node->tn_mtime.tv_sec; 467 sb->st_mtim.tv_nsec = node->tn_mtime.tv_nsec; 468 sb->st_ctim.tv_sec = node->tn_ctime.tv_sec; 469 sb->st_ctim.tv_nsec = node->tn_ctime.tv_nsec; 470 sb->st_birthtim.tv_sec = node->tn_birthtime.tv_sec; 471 sb->st_birthtim.tv_nsec = node->tn_birthtime.tv_nsec; 472 sb->st_blksize = PAGE_SIZE; 473 sb->st_flags = node->tn_flags; 474 sb->st_gen = node->tn_gen; 475 if (vp->v_type == VREG) { 476 obj = node->tn_reg.tn_aobj; 477 sb->st_blocks = (u_quad_t)obj->resident_page_count * PAGE_SIZE; 478 } else 479 sb->st_blocks = node->tn_size; 480 sb->st_blocks /= S_BLKSIZE; 481 return (vop_stat_helper_post(v, error)); 482 } 483 484 int 485 tmpfs_getattr(struct vop_getattr_args *v) 486 { 487 struct vnode *vp = v->a_vp; 488 struct vattr *vap = v->a_vap; 489 vm_object_t obj; 490 struct tmpfs_node *node; 491 492 node = VP_TO_TMPFS_NODE(vp); 493 494 tmpfs_update_getattr(vp); 495 496 vap->va_type = vp->v_type; 497 vap->va_mode = node->tn_mode; 498 vap->va_nlink = node->tn_links; 499 vap->va_uid = node->tn_uid; 500 vap->va_gid = node->tn_gid; 501 vap->va_fsid = vp->v_mount->mnt_stat.f_fsid.val[0]; 502 vap->va_fileid = node->tn_id; 503 vap->va_size = node->tn_size; 504 vap->va_blocksize = PAGE_SIZE; 505 vap->va_atime = node->tn_atime; 506 vap->va_mtime = node->tn_mtime; 507 vap->va_ctime = node->tn_ctime; 508 vap->va_birthtime = node->tn_birthtime; 509 vap->va_gen = node->tn_gen; 510 vap->va_flags = node->tn_flags; 511 vap->va_rdev = (vp->v_type == VBLK || vp->v_type == VCHR) ? 512 node->tn_rdev : NODEV; 513 if (vp->v_type == VREG) { 514 obj = node->tn_reg.tn_aobj; 515 vap->va_bytes = (u_quad_t)obj->resident_page_count * PAGE_SIZE; 516 } else 517 vap->va_bytes = node->tn_size; 518 vap->va_filerev = 0; 519 520 return 0; 521 } 522 523 int 524 tmpfs_setattr(struct vop_setattr_args *v) 525 { 526 struct vnode *vp = v->a_vp; 527 struct vattr *vap = v->a_vap; 528 struct ucred *cred = v->a_cred; 529 struct thread *td = curthread; 530 531 int error; 532 533 MPASS(VOP_ISLOCKED(vp)); 534 ASSERT_VOP_IN_SEQC(vp); 535 536 error = 0; 537 538 /* Abort if any unsettable attribute is given. */ 539 if (vap->va_type != VNON || 540 vap->va_nlink != VNOVAL || 541 vap->va_fsid != VNOVAL || 542 vap->va_fileid != VNOVAL || 543 vap->va_blocksize != VNOVAL || 544 vap->va_gen != VNOVAL || 545 vap->va_rdev != VNOVAL || 546 vap->va_bytes != VNOVAL) 547 error = EINVAL; 548 549 if (error == 0 && (vap->va_flags != VNOVAL)) 550 error = tmpfs_chflags(vp, vap->va_flags, cred, td); 551 552 if (error == 0 && (vap->va_size != VNOVAL)) 553 error = tmpfs_chsize(vp, vap->va_size, cred, td); 554 555 if (error == 0 && (vap->va_uid != VNOVAL || vap->va_gid != VNOVAL)) 556 error = tmpfs_chown(vp, vap->va_uid, vap->va_gid, cred, td); 557 558 if (error == 0 && (vap->va_mode != (mode_t)VNOVAL)) 559 error = tmpfs_chmod(vp, vap->va_mode, cred, td); 560 561 if (error == 0 && ((vap->va_atime.tv_sec != VNOVAL && 562 vap->va_atime.tv_nsec != VNOVAL) || 563 (vap->va_mtime.tv_sec != VNOVAL && 564 vap->va_mtime.tv_nsec != VNOVAL) || 565 (vap->va_birthtime.tv_sec != VNOVAL && 566 vap->va_birthtime.tv_nsec != VNOVAL))) 567 error = tmpfs_chtimes(vp, vap, cred, td); 568 569 /* 570 * Update the node times. We give preference to the error codes 571 * generated by this function rather than the ones that may arise 572 * from tmpfs_update. 573 */ 574 tmpfs_update(vp); 575 576 MPASS(VOP_ISLOCKED(vp)); 577 578 return error; 579 } 580 581 static int 582 tmpfs_read(struct vop_read_args *v) 583 { 584 struct vnode *vp; 585 struct uio *uio; 586 struct tmpfs_node *node; 587 588 vp = v->a_vp; 589 if (vp->v_type != VREG) 590 return (EISDIR); 591 uio = v->a_uio; 592 if (uio->uio_offset < 0) 593 return (EINVAL); 594 node = VP_TO_TMPFS_NODE(vp); 595 tmpfs_set_accessed(VFS_TO_TMPFS(vp->v_mount), node); 596 return (uiomove_object(node->tn_reg.tn_aobj, node->tn_size, uio)); 597 } 598 599 static int 600 tmpfs_read_pgcache(struct vop_read_pgcache_args *v) 601 { 602 struct vnode *vp; 603 struct tmpfs_node *node; 604 vm_object_t object; 605 off_t size; 606 int error; 607 608 vp = v->a_vp; 609 VNPASS((vn_irflag_read(vp) & VIRF_PGREAD) != 0, vp); 610 611 if (v->a_uio->uio_offset < 0) 612 return (EINVAL); 613 614 error = EJUSTRETURN; 615 vfs_smr_enter(); 616 617 node = VP_TO_TMPFS_NODE_SMR(vp); 618 if (node == NULL) 619 goto out_smr; 620 MPASS(node->tn_type == VREG); 621 MPASS(node->tn_refcount >= 1); 622 object = node->tn_reg.tn_aobj; 623 if (object == NULL) 624 goto out_smr; 625 626 MPASS((object->flags & (OBJ_ANON | OBJ_DEAD | OBJ_TMPFS_NODE)) == 627 OBJ_TMPFS_NODE); 628 if (!VN_IS_DOOMED(vp)) { 629 /* size cannot become shorter due to rangelock. */ 630 size = node->tn_size; 631 tmpfs_set_accessed(node->tn_reg.tn_tmp, node); 632 vfs_smr_exit(); 633 error = uiomove_object(object, size, v->a_uio); 634 return (error); 635 } 636 out_smr: 637 vfs_smr_exit(); 638 return (error); 639 } 640 641 static int 642 tmpfs_write(struct vop_write_args *v) 643 { 644 struct vnode *vp; 645 struct uio *uio; 646 struct tmpfs_node *node; 647 off_t oldsize; 648 int error, ioflag; 649 mode_t newmode; 650 651 vp = v->a_vp; 652 uio = v->a_uio; 653 ioflag = v->a_ioflag; 654 error = 0; 655 node = VP_TO_TMPFS_NODE(vp); 656 oldsize = node->tn_size; 657 658 if (uio->uio_offset < 0 || vp->v_type != VREG) 659 return (EINVAL); 660 if (uio->uio_resid == 0) 661 return (0); 662 if (ioflag & IO_APPEND) 663 uio->uio_offset = node->tn_size; 664 if (uio->uio_offset + uio->uio_resid > 665 VFS_TO_TMPFS(vp->v_mount)->tm_maxfilesize) 666 return (EFBIG); 667 if (vn_rlimit_fsize(vp, uio, uio->uio_td)) 668 return (EFBIG); 669 if (uio->uio_offset + uio->uio_resid > node->tn_size) { 670 error = tmpfs_reg_resize(vp, uio->uio_offset + uio->uio_resid, 671 FALSE); 672 if (error != 0) 673 goto out; 674 } 675 676 error = uiomove_object(node->tn_reg.tn_aobj, node->tn_size, uio); 677 node->tn_status |= TMPFS_NODE_MODIFIED | TMPFS_NODE_CHANGED; 678 node->tn_accessed = true; 679 if (node->tn_mode & (S_ISUID | S_ISGID)) { 680 if (priv_check_cred(v->a_cred, PRIV_VFS_RETAINSUGID)) { 681 newmode = node->tn_mode & ~(S_ISUID | S_ISGID); 682 vn_seqc_write_begin(vp); 683 atomic_store_short(&node->tn_mode, newmode); 684 vn_seqc_write_end(vp); 685 } 686 } 687 if (error != 0) 688 (void)tmpfs_reg_resize(vp, oldsize, TRUE); 689 690 out: 691 MPASS(IMPLIES(error == 0, uio->uio_resid == 0)); 692 MPASS(IMPLIES(error != 0, oldsize == node->tn_size)); 693 694 return (error); 695 } 696 697 static int 698 tmpfs_fsync(struct vop_fsync_args *v) 699 { 700 struct vnode *vp = v->a_vp; 701 702 MPASS(VOP_ISLOCKED(vp)); 703 704 tmpfs_check_mtime(vp); 705 tmpfs_update(vp); 706 707 return 0; 708 } 709 710 static int 711 tmpfs_remove(struct vop_remove_args *v) 712 { 713 struct vnode *dvp = v->a_dvp; 714 struct vnode *vp = v->a_vp; 715 716 int error; 717 struct tmpfs_dirent *de; 718 struct tmpfs_mount *tmp; 719 struct tmpfs_node *dnode; 720 struct tmpfs_node *node; 721 722 MPASS(VOP_ISLOCKED(dvp)); 723 MPASS(VOP_ISLOCKED(vp)); 724 725 if (vp->v_type == VDIR) { 726 error = EISDIR; 727 goto out; 728 } 729 730 dnode = VP_TO_TMPFS_DIR(dvp); 731 node = VP_TO_TMPFS_NODE(vp); 732 tmp = VFS_TO_TMPFS(vp->v_mount); 733 de = tmpfs_dir_lookup(dnode, node, v->a_cnp); 734 MPASS(de != NULL); 735 736 /* Files marked as immutable or append-only cannot be deleted. */ 737 if ((node->tn_flags & (IMMUTABLE | APPEND | NOUNLINK)) || 738 (dnode->tn_flags & APPEND)) { 739 error = EPERM; 740 goto out; 741 } 742 743 /* Remove the entry from the directory; as it is a file, we do not 744 * have to change the number of hard links of the directory. */ 745 tmpfs_dir_detach(dvp, de); 746 if (v->a_cnp->cn_flags & DOWHITEOUT) 747 tmpfs_dir_whiteout_add(dvp, v->a_cnp); 748 749 /* Free the directory entry we just deleted. Note that the node 750 * referred by it will not be removed until the vnode is really 751 * reclaimed. */ 752 tmpfs_free_dirent(tmp, de); 753 754 node->tn_status |= TMPFS_NODE_CHANGED; 755 node->tn_accessed = true; 756 error = 0; 757 758 out: 759 return (error); 760 } 761 762 static int 763 tmpfs_link(struct vop_link_args *v) 764 { 765 struct vnode *dvp = v->a_tdvp; 766 struct vnode *vp = v->a_vp; 767 struct componentname *cnp = v->a_cnp; 768 769 int error; 770 struct tmpfs_dirent *de; 771 struct tmpfs_node *node; 772 773 MPASS(VOP_ISLOCKED(dvp)); 774 MPASS(cnp->cn_flags & HASBUF); 775 MPASS(dvp != vp); /* XXX When can this be false? */ 776 node = VP_TO_TMPFS_NODE(vp); 777 778 /* Ensure that we do not overflow the maximum number of links imposed 779 * by the system. */ 780 MPASS(node->tn_links <= TMPFS_LINK_MAX); 781 if (node->tn_links == TMPFS_LINK_MAX) { 782 error = EMLINK; 783 goto out; 784 } 785 786 /* We cannot create links of files marked immutable or append-only. */ 787 if (node->tn_flags & (IMMUTABLE | APPEND)) { 788 error = EPERM; 789 goto out; 790 } 791 792 /* Allocate a new directory entry to represent the node. */ 793 error = tmpfs_alloc_dirent(VFS_TO_TMPFS(vp->v_mount), node, 794 cnp->cn_nameptr, cnp->cn_namelen, &de); 795 if (error != 0) 796 goto out; 797 798 /* Insert the new directory entry into the appropriate directory. */ 799 if (cnp->cn_flags & ISWHITEOUT) 800 tmpfs_dir_whiteout_remove(dvp, cnp); 801 tmpfs_dir_attach(dvp, de); 802 803 /* vp link count has changed, so update node times. */ 804 node->tn_status |= TMPFS_NODE_CHANGED; 805 tmpfs_update(vp); 806 807 error = 0; 808 809 out: 810 return error; 811 } 812 813 /* 814 * We acquire all but fdvp locks using non-blocking acquisitions. If we 815 * fail to acquire any lock in the path we will drop all held locks, 816 * acquire the new lock in a blocking fashion, and then release it and 817 * restart the rename. This acquire/release step ensures that we do not 818 * spin on a lock waiting for release. On error release all vnode locks 819 * and decrement references the way tmpfs_rename() would do. 820 */ 821 static int 822 tmpfs_rename_relock(struct vnode *fdvp, struct vnode **fvpp, 823 struct vnode *tdvp, struct vnode **tvpp, 824 struct componentname *fcnp, struct componentname *tcnp) 825 { 826 struct vnode *nvp; 827 struct mount *mp; 828 struct tmpfs_dirent *de; 829 int error, restarts = 0; 830 831 VOP_UNLOCK(tdvp); 832 if (*tvpp != NULL && *tvpp != tdvp) 833 VOP_UNLOCK(*tvpp); 834 mp = fdvp->v_mount; 835 836 relock: 837 restarts += 1; 838 error = vn_lock(fdvp, LK_EXCLUSIVE); 839 if (error) 840 goto releout; 841 if (vn_lock(tdvp, LK_EXCLUSIVE | LK_NOWAIT) != 0) { 842 VOP_UNLOCK(fdvp); 843 error = vn_lock(tdvp, LK_EXCLUSIVE); 844 if (error) 845 goto releout; 846 VOP_UNLOCK(tdvp); 847 goto relock; 848 } 849 /* 850 * Re-resolve fvp to be certain it still exists and fetch the 851 * correct vnode. 852 */ 853 de = tmpfs_dir_lookup(VP_TO_TMPFS_DIR(fdvp), NULL, fcnp); 854 if (de == NULL) { 855 VOP_UNLOCK(fdvp); 856 VOP_UNLOCK(tdvp); 857 if ((fcnp->cn_flags & ISDOTDOT) != 0 || 858 (fcnp->cn_namelen == 1 && fcnp->cn_nameptr[0] == '.')) 859 error = EINVAL; 860 else 861 error = ENOENT; 862 goto releout; 863 } 864 error = tmpfs_alloc_vp(mp, de->td_node, LK_EXCLUSIVE | LK_NOWAIT, &nvp); 865 if (error != 0) { 866 VOP_UNLOCK(fdvp); 867 VOP_UNLOCK(tdvp); 868 if (error != EBUSY) 869 goto releout; 870 error = tmpfs_alloc_vp(mp, de->td_node, LK_EXCLUSIVE, &nvp); 871 if (error != 0) 872 goto releout; 873 VOP_UNLOCK(nvp); 874 /* 875 * Concurrent rename race. 876 */ 877 if (nvp == tdvp) { 878 vrele(nvp); 879 error = EINVAL; 880 goto releout; 881 } 882 vrele(*fvpp); 883 *fvpp = nvp; 884 goto relock; 885 } 886 vrele(*fvpp); 887 *fvpp = nvp; 888 VOP_UNLOCK(*fvpp); 889 /* 890 * Re-resolve tvp and acquire the vnode lock if present. 891 */ 892 de = tmpfs_dir_lookup(VP_TO_TMPFS_DIR(tdvp), NULL, tcnp); 893 /* 894 * If tvp disappeared we just carry on. 895 */ 896 if (de == NULL && *tvpp != NULL) { 897 vrele(*tvpp); 898 *tvpp = NULL; 899 } 900 /* 901 * Get the tvp ino if the lookup succeeded. We may have to restart 902 * if the non-blocking acquire fails. 903 */ 904 if (de != NULL) { 905 nvp = NULL; 906 error = tmpfs_alloc_vp(mp, de->td_node, 907 LK_EXCLUSIVE | LK_NOWAIT, &nvp); 908 if (*tvpp != NULL) 909 vrele(*tvpp); 910 *tvpp = nvp; 911 if (error != 0) { 912 VOP_UNLOCK(fdvp); 913 VOP_UNLOCK(tdvp); 914 if (error != EBUSY) 915 goto releout; 916 error = tmpfs_alloc_vp(mp, de->td_node, LK_EXCLUSIVE, 917 &nvp); 918 if (error != 0) 919 goto releout; 920 VOP_UNLOCK(nvp); 921 /* 922 * fdvp contains fvp, thus tvp (=fdvp) is not empty. 923 */ 924 if (nvp == fdvp) { 925 error = ENOTEMPTY; 926 goto releout; 927 } 928 goto relock; 929 } 930 } 931 tmpfs_rename_restarts += restarts; 932 933 return (0); 934 935 releout: 936 vrele(fdvp); 937 vrele(*fvpp); 938 vrele(tdvp); 939 if (*tvpp != NULL) 940 vrele(*tvpp); 941 tmpfs_rename_restarts += restarts; 942 943 return (error); 944 } 945 946 static int 947 tmpfs_rename(struct vop_rename_args *v) 948 { 949 struct vnode *fdvp = v->a_fdvp; 950 struct vnode *fvp = v->a_fvp; 951 struct componentname *fcnp = v->a_fcnp; 952 struct vnode *tdvp = v->a_tdvp; 953 struct vnode *tvp = v->a_tvp; 954 struct componentname *tcnp = v->a_tcnp; 955 char *newname; 956 struct tmpfs_dirent *de; 957 struct tmpfs_mount *tmp; 958 struct tmpfs_node *fdnode; 959 struct tmpfs_node *fnode; 960 struct tmpfs_node *tnode; 961 struct tmpfs_node *tdnode; 962 int error; 963 bool want_seqc_end; 964 965 MPASS(VOP_ISLOCKED(tdvp)); 966 MPASS(IMPLIES(tvp != NULL, VOP_ISLOCKED(tvp))); 967 MPASS(fcnp->cn_flags & HASBUF); 968 MPASS(tcnp->cn_flags & HASBUF); 969 970 want_seqc_end = false; 971 972 /* 973 * Disallow cross-device renames. 974 * XXX Why isn't this done by the caller? 975 */ 976 if (fvp->v_mount != tdvp->v_mount || 977 (tvp != NULL && fvp->v_mount != tvp->v_mount)) { 978 error = EXDEV; 979 goto out; 980 } 981 982 /* If source and target are the same file, there is nothing to do. */ 983 if (fvp == tvp) { 984 error = 0; 985 goto out; 986 } 987 988 /* 989 * If we need to move the directory between entries, lock the 990 * source so that we can safely operate on it. 991 */ 992 if (fdvp != tdvp && fdvp != tvp) { 993 if (vn_lock(fdvp, LK_EXCLUSIVE | LK_NOWAIT) != 0) { 994 error = tmpfs_rename_relock(fdvp, &fvp, tdvp, &tvp, 995 fcnp, tcnp); 996 if (error != 0) 997 return (error); 998 ASSERT_VOP_ELOCKED(fdvp, 999 "tmpfs_rename: fdvp not locked"); 1000 ASSERT_VOP_ELOCKED(tdvp, 1001 "tmpfs_rename: tdvp not locked"); 1002 if (tvp != NULL) 1003 ASSERT_VOP_ELOCKED(tvp, 1004 "tmpfs_rename: tvp not locked"); 1005 if (fvp == tvp) { 1006 error = 0; 1007 goto out_locked; 1008 } 1009 } 1010 } 1011 1012 if (tvp != NULL) 1013 vn_seqc_write_begin(tvp); 1014 vn_seqc_write_begin(tdvp); 1015 vn_seqc_write_begin(fvp); 1016 vn_seqc_write_begin(fdvp); 1017 want_seqc_end = true; 1018 1019 tmp = VFS_TO_TMPFS(tdvp->v_mount); 1020 tdnode = VP_TO_TMPFS_DIR(tdvp); 1021 tnode = (tvp == NULL) ? NULL : VP_TO_TMPFS_NODE(tvp); 1022 fdnode = VP_TO_TMPFS_DIR(fdvp); 1023 fnode = VP_TO_TMPFS_NODE(fvp); 1024 de = tmpfs_dir_lookup(fdnode, fnode, fcnp); 1025 1026 /* 1027 * Entry can disappear before we lock fdvp, 1028 * also avoid manipulating '.' and '..' entries. 1029 */ 1030 if (de == NULL) { 1031 if ((fcnp->cn_flags & ISDOTDOT) != 0 || 1032 (fcnp->cn_namelen == 1 && fcnp->cn_nameptr[0] == '.')) 1033 error = EINVAL; 1034 else 1035 error = ENOENT; 1036 goto out_locked; 1037 } 1038 MPASS(de->td_node == fnode); 1039 1040 /* 1041 * If re-naming a directory to another preexisting directory 1042 * ensure that the target directory is empty so that its 1043 * removal causes no side effects. 1044 * Kern_rename guarantees the destination to be a directory 1045 * if the source is one. 1046 */ 1047 if (tvp != NULL) { 1048 MPASS(tnode != NULL); 1049 1050 if ((tnode->tn_flags & (NOUNLINK | IMMUTABLE | APPEND)) || 1051 (tdnode->tn_flags & (APPEND | IMMUTABLE))) { 1052 error = EPERM; 1053 goto out_locked; 1054 } 1055 1056 if (fnode->tn_type == VDIR && tnode->tn_type == VDIR) { 1057 if (tnode->tn_size > 0) { 1058 error = ENOTEMPTY; 1059 goto out_locked; 1060 } 1061 } else if (fnode->tn_type == VDIR && tnode->tn_type != VDIR) { 1062 error = ENOTDIR; 1063 goto out_locked; 1064 } else if (fnode->tn_type != VDIR && tnode->tn_type == VDIR) { 1065 error = EISDIR; 1066 goto out_locked; 1067 } else { 1068 MPASS(fnode->tn_type != VDIR && 1069 tnode->tn_type != VDIR); 1070 } 1071 } 1072 1073 if ((fnode->tn_flags & (NOUNLINK | IMMUTABLE | APPEND)) 1074 || (fdnode->tn_flags & (APPEND | IMMUTABLE))) { 1075 error = EPERM; 1076 goto out_locked; 1077 } 1078 1079 /* 1080 * Ensure that we have enough memory to hold the new name, if it 1081 * has to be changed. 1082 */ 1083 if (fcnp->cn_namelen != tcnp->cn_namelen || 1084 bcmp(fcnp->cn_nameptr, tcnp->cn_nameptr, fcnp->cn_namelen) != 0) { 1085 newname = malloc(tcnp->cn_namelen, M_TMPFSNAME, M_WAITOK); 1086 } else 1087 newname = NULL; 1088 1089 /* 1090 * If the node is being moved to another directory, we have to do 1091 * the move. 1092 */ 1093 if (fdnode != tdnode) { 1094 /* 1095 * In case we are moving a directory, we have to adjust its 1096 * parent to point to the new parent. 1097 */ 1098 if (de->td_node->tn_type == VDIR) { 1099 struct tmpfs_node *n; 1100 1101 /* 1102 * Ensure the target directory is not a child of the 1103 * directory being moved. Otherwise, we'd end up 1104 * with stale nodes. 1105 */ 1106 n = tdnode; 1107 /* 1108 * TMPFS_LOCK guaranties that no nodes are freed while 1109 * traversing the list. Nodes can only be marked as 1110 * removed: tn_parent == NULL. 1111 */ 1112 TMPFS_LOCK(tmp); 1113 TMPFS_NODE_LOCK(n); 1114 while (n != n->tn_dir.tn_parent) { 1115 struct tmpfs_node *parent; 1116 1117 if (n == fnode) { 1118 TMPFS_NODE_UNLOCK(n); 1119 TMPFS_UNLOCK(tmp); 1120 error = EINVAL; 1121 if (newname != NULL) 1122 free(newname, M_TMPFSNAME); 1123 goto out_locked; 1124 } 1125 parent = n->tn_dir.tn_parent; 1126 TMPFS_NODE_UNLOCK(n); 1127 if (parent == NULL) { 1128 n = NULL; 1129 break; 1130 } 1131 TMPFS_NODE_LOCK(parent); 1132 if (parent->tn_dir.tn_parent == NULL) { 1133 TMPFS_NODE_UNLOCK(parent); 1134 n = NULL; 1135 break; 1136 } 1137 n = parent; 1138 } 1139 TMPFS_UNLOCK(tmp); 1140 if (n == NULL) { 1141 error = EINVAL; 1142 if (newname != NULL) 1143 free(newname, M_TMPFSNAME); 1144 goto out_locked; 1145 } 1146 TMPFS_NODE_UNLOCK(n); 1147 1148 /* Adjust the parent pointer. */ 1149 TMPFS_VALIDATE_DIR(fnode); 1150 TMPFS_NODE_LOCK(de->td_node); 1151 de->td_node->tn_dir.tn_parent = tdnode; 1152 TMPFS_NODE_UNLOCK(de->td_node); 1153 1154 /* 1155 * As a result of changing the target of the '..' 1156 * entry, the link count of the source and target 1157 * directories has to be adjusted. 1158 */ 1159 TMPFS_NODE_LOCK(tdnode); 1160 TMPFS_ASSERT_LOCKED(tdnode); 1161 tdnode->tn_links++; 1162 TMPFS_NODE_UNLOCK(tdnode); 1163 1164 TMPFS_NODE_LOCK(fdnode); 1165 TMPFS_ASSERT_LOCKED(fdnode); 1166 fdnode->tn_links--; 1167 TMPFS_NODE_UNLOCK(fdnode); 1168 } 1169 } 1170 1171 /* 1172 * Do the move: just remove the entry from the source directory 1173 * and insert it into the target one. 1174 */ 1175 tmpfs_dir_detach(fdvp, de); 1176 1177 if (fcnp->cn_flags & DOWHITEOUT) 1178 tmpfs_dir_whiteout_add(fdvp, fcnp); 1179 if (tcnp->cn_flags & ISWHITEOUT) 1180 tmpfs_dir_whiteout_remove(tdvp, tcnp); 1181 1182 /* 1183 * If the name has changed, we need to make it effective by changing 1184 * it in the directory entry. 1185 */ 1186 if (newname != NULL) { 1187 MPASS(tcnp->cn_namelen <= MAXNAMLEN); 1188 1189 free(de->ud.td_name, M_TMPFSNAME); 1190 de->ud.td_name = newname; 1191 tmpfs_dirent_init(de, tcnp->cn_nameptr, tcnp->cn_namelen); 1192 1193 fnode->tn_status |= TMPFS_NODE_CHANGED; 1194 tdnode->tn_status |= TMPFS_NODE_MODIFIED; 1195 } 1196 1197 /* 1198 * If we are overwriting an entry, we have to remove the old one 1199 * from the target directory. 1200 */ 1201 if (tvp != NULL) { 1202 struct tmpfs_dirent *tde; 1203 1204 /* Remove the old entry from the target directory. */ 1205 tde = tmpfs_dir_lookup(tdnode, tnode, tcnp); 1206 tmpfs_dir_detach(tdvp, tde); 1207 1208 /* 1209 * Free the directory entry we just deleted. Note that the 1210 * node referred by it will not be removed until the vnode is 1211 * really reclaimed. 1212 */ 1213 tmpfs_free_dirent(VFS_TO_TMPFS(tvp->v_mount), tde); 1214 } 1215 1216 tmpfs_dir_attach(tdvp, de); 1217 1218 if (tmpfs_use_nc(fvp)) { 1219 cache_vop_rename(fdvp, fvp, tdvp, tvp, fcnp, tcnp); 1220 } 1221 1222 error = 0; 1223 1224 out_locked: 1225 if (fdvp != tdvp && fdvp != tvp) 1226 VOP_UNLOCK(fdvp); 1227 1228 out: 1229 if (want_seqc_end) { 1230 if (tvp != NULL) 1231 vn_seqc_write_end(tvp); 1232 vn_seqc_write_end(tdvp); 1233 vn_seqc_write_end(fvp); 1234 vn_seqc_write_end(fdvp); 1235 } 1236 1237 /* 1238 * Release target nodes. 1239 * XXX: I don't understand when tdvp can be the same as tvp, but 1240 * other code takes care of this... 1241 */ 1242 if (tdvp == tvp) 1243 vrele(tdvp); 1244 else 1245 vput(tdvp); 1246 if (tvp != NULL) 1247 vput(tvp); 1248 1249 /* Release source nodes. */ 1250 vrele(fdvp); 1251 vrele(fvp); 1252 1253 return (error); 1254 } 1255 1256 static int 1257 tmpfs_mkdir(struct vop_mkdir_args *v) 1258 { 1259 struct vnode *dvp = v->a_dvp; 1260 struct vnode **vpp = v->a_vpp; 1261 struct componentname *cnp = v->a_cnp; 1262 struct vattr *vap = v->a_vap; 1263 1264 MPASS(vap->va_type == VDIR); 1265 1266 return tmpfs_alloc_file(dvp, vpp, vap, cnp, NULL); 1267 } 1268 1269 static int 1270 tmpfs_rmdir(struct vop_rmdir_args *v) 1271 { 1272 struct vnode *dvp = v->a_dvp; 1273 struct vnode *vp = v->a_vp; 1274 1275 int error; 1276 struct tmpfs_dirent *de; 1277 struct tmpfs_mount *tmp; 1278 struct tmpfs_node *dnode; 1279 struct tmpfs_node *node; 1280 1281 MPASS(VOP_ISLOCKED(dvp)); 1282 MPASS(VOP_ISLOCKED(vp)); 1283 1284 tmp = VFS_TO_TMPFS(dvp->v_mount); 1285 dnode = VP_TO_TMPFS_DIR(dvp); 1286 node = VP_TO_TMPFS_DIR(vp); 1287 1288 /* Directories with more than two entries ('.' and '..') cannot be 1289 * removed. */ 1290 if (node->tn_size > 0) { 1291 error = ENOTEMPTY; 1292 goto out; 1293 } 1294 1295 if ((dnode->tn_flags & APPEND) 1296 || (node->tn_flags & (NOUNLINK | IMMUTABLE | APPEND))) { 1297 error = EPERM; 1298 goto out; 1299 } 1300 1301 /* This invariant holds only if we are not trying to remove "..". 1302 * We checked for that above so this is safe now. */ 1303 MPASS(node->tn_dir.tn_parent == dnode); 1304 1305 /* Get the directory entry associated with node (vp). This was 1306 * filled by tmpfs_lookup while looking up the entry. */ 1307 de = tmpfs_dir_lookup(dnode, node, v->a_cnp); 1308 MPASS(TMPFS_DIRENT_MATCHES(de, 1309 v->a_cnp->cn_nameptr, 1310 v->a_cnp->cn_namelen)); 1311 1312 /* Check flags to see if we are allowed to remove the directory. */ 1313 if ((dnode->tn_flags & APPEND) != 0 || 1314 (node->tn_flags & (NOUNLINK | IMMUTABLE | APPEND)) != 0) { 1315 error = EPERM; 1316 goto out; 1317 } 1318 1319 /* Detach the directory entry from the directory (dnode). */ 1320 tmpfs_dir_detach(dvp, de); 1321 if (v->a_cnp->cn_flags & DOWHITEOUT) 1322 tmpfs_dir_whiteout_add(dvp, v->a_cnp); 1323 1324 /* No vnode should be allocated for this entry from this point */ 1325 TMPFS_NODE_LOCK(node); 1326 node->tn_links--; 1327 node->tn_dir.tn_parent = NULL; 1328 node->tn_status |= TMPFS_NODE_CHANGED | TMPFS_NODE_MODIFIED; 1329 node->tn_accessed = true; 1330 1331 TMPFS_NODE_UNLOCK(node); 1332 1333 TMPFS_NODE_LOCK(dnode); 1334 dnode->tn_links--; 1335 dnode->tn_status |= TMPFS_NODE_CHANGED | TMPFS_NODE_MODIFIED; 1336 dnode->tn_accessed = true; 1337 TMPFS_NODE_UNLOCK(dnode); 1338 1339 if (tmpfs_use_nc(dvp)) { 1340 cache_vop_rmdir(dvp, vp); 1341 } 1342 1343 /* Free the directory entry we just deleted. Note that the node 1344 * referred by it will not be removed until the vnode is really 1345 * reclaimed. */ 1346 tmpfs_free_dirent(tmp, de); 1347 1348 /* Release the deleted vnode (will destroy the node, notify 1349 * interested parties and clean it from the cache). */ 1350 1351 dnode->tn_status |= TMPFS_NODE_CHANGED; 1352 tmpfs_update(dvp); 1353 1354 error = 0; 1355 1356 out: 1357 return error; 1358 } 1359 1360 static int 1361 tmpfs_symlink(struct vop_symlink_args *v) 1362 { 1363 struct vnode *dvp = v->a_dvp; 1364 struct vnode **vpp = v->a_vpp; 1365 struct componentname *cnp = v->a_cnp; 1366 struct vattr *vap = v->a_vap; 1367 const char *target = v->a_target; 1368 1369 #ifdef notyet /* XXX FreeBSD BUG: kern_symlink is not setting VLNK */ 1370 MPASS(vap->va_type == VLNK); 1371 #else 1372 vap->va_type = VLNK; 1373 #endif 1374 1375 return tmpfs_alloc_file(dvp, vpp, vap, cnp, target); 1376 } 1377 1378 static int 1379 tmpfs_readdir(struct vop_readdir_args *va) 1380 { 1381 struct vnode *vp; 1382 struct uio *uio; 1383 struct tmpfs_mount *tm; 1384 struct tmpfs_node *node; 1385 u_long **cookies; 1386 int *eofflag, *ncookies; 1387 ssize_t startresid; 1388 int error, maxcookies; 1389 1390 vp = va->a_vp; 1391 uio = va->a_uio; 1392 eofflag = va->a_eofflag; 1393 cookies = va->a_cookies; 1394 ncookies = va->a_ncookies; 1395 1396 /* This operation only makes sense on directory nodes. */ 1397 if (vp->v_type != VDIR) 1398 return ENOTDIR; 1399 1400 maxcookies = 0; 1401 node = VP_TO_TMPFS_DIR(vp); 1402 tm = VFS_TO_TMPFS(vp->v_mount); 1403 1404 startresid = uio->uio_resid; 1405 1406 /* Allocate cookies for NFS and compat modules. */ 1407 if (cookies != NULL && ncookies != NULL) { 1408 maxcookies = howmany(node->tn_size, 1409 sizeof(struct tmpfs_dirent)) + 2; 1410 *cookies = malloc(maxcookies * sizeof(**cookies), M_TEMP, 1411 M_WAITOK); 1412 *ncookies = 0; 1413 } 1414 1415 if (cookies == NULL) 1416 error = tmpfs_dir_getdents(tm, node, uio, 0, NULL, NULL); 1417 else 1418 error = tmpfs_dir_getdents(tm, node, uio, maxcookies, *cookies, 1419 ncookies); 1420 1421 /* Buffer was filled without hitting EOF. */ 1422 if (error == EJUSTRETURN) 1423 error = (uio->uio_resid != startresid) ? 0 : EINVAL; 1424 1425 if (error != 0 && cookies != NULL && ncookies != NULL) { 1426 free(*cookies, M_TEMP); 1427 *cookies = NULL; 1428 *ncookies = 0; 1429 } 1430 1431 if (eofflag != NULL) 1432 *eofflag = 1433 (error == 0 && uio->uio_offset == TMPFS_DIRCOOKIE_EOF); 1434 1435 return error; 1436 } 1437 1438 static int 1439 tmpfs_readlink(struct vop_readlink_args *v) 1440 { 1441 struct vnode *vp = v->a_vp; 1442 struct uio *uio = v->a_uio; 1443 1444 int error; 1445 struct tmpfs_node *node; 1446 1447 MPASS(uio->uio_offset == 0); 1448 MPASS(vp->v_type == VLNK); 1449 1450 node = VP_TO_TMPFS_NODE(vp); 1451 1452 error = uiomove(node->tn_link_target, MIN(node->tn_size, uio->uio_resid), 1453 uio); 1454 tmpfs_set_accessed(VFS_TO_TMPFS(vp->v_mount), node); 1455 1456 return (error); 1457 } 1458 1459 /* 1460 * VOP_FPLOOKUP_SYMLINK routines are subject to special circumstances, see 1461 * the comment above cache_fplookup for details. 1462 * 1463 * Check tmpfs_alloc_node for tmpfs-specific synchronisation notes. 1464 */ 1465 static int 1466 tmpfs_fplookup_symlink(struct vop_fplookup_symlink_args *v) 1467 { 1468 struct vnode *vp; 1469 struct tmpfs_node *node; 1470 char *symlink; 1471 1472 vp = v->a_vp; 1473 node = VP_TO_TMPFS_NODE_SMR(vp); 1474 if (__predict_false(node == NULL)) 1475 return (EAGAIN); 1476 if (!atomic_load_char(&node->tn_link_smr)) 1477 return (EAGAIN); 1478 symlink = atomic_load_ptr(&node->tn_link_target); 1479 if (symlink == NULL) 1480 return (EAGAIN); 1481 1482 return (cache_symlink_resolve(v->a_fpl, symlink, node->tn_size)); 1483 } 1484 1485 static int 1486 tmpfs_inactive(struct vop_inactive_args *v) 1487 { 1488 struct vnode *vp; 1489 struct tmpfs_node *node; 1490 1491 vp = v->a_vp; 1492 node = VP_TO_TMPFS_NODE(vp); 1493 if (node->tn_links == 0) 1494 vrecycle(vp); 1495 else 1496 tmpfs_check_mtime(vp); 1497 return (0); 1498 } 1499 1500 static int 1501 tmpfs_need_inactive(struct vop_need_inactive_args *ap) 1502 { 1503 struct vnode *vp; 1504 struct tmpfs_node *node; 1505 struct vm_object *obj; 1506 1507 vp = ap->a_vp; 1508 node = VP_TO_TMPFS_NODE(vp); 1509 if (node->tn_links == 0) 1510 goto need; 1511 if (vp->v_type == VREG) { 1512 obj = vp->v_object; 1513 if (obj->generation != obj->cleangeneration) 1514 goto need; 1515 } 1516 return (0); 1517 need: 1518 return (1); 1519 } 1520 1521 int 1522 tmpfs_reclaim(struct vop_reclaim_args *v) 1523 { 1524 struct vnode *vp; 1525 struct tmpfs_mount *tmp; 1526 struct tmpfs_node *node; 1527 bool unlock, tm_locked; 1528 1529 vp = v->a_vp; 1530 node = VP_TO_TMPFS_NODE(vp); 1531 tmp = VFS_TO_TMPFS(vp->v_mount); 1532 tm_locked = false; 1533 1534 if (vp->v_type == VREG) 1535 tmpfs_destroy_vobject(vp, node->tn_reg.tn_aobj); 1536 vp->v_object = NULL; 1537 1538 relock: 1539 TMPFS_NODE_LOCK(node); 1540 if (!tm_locked && node->tn_links == 0 && 1541 (node->tn_vpstate & TMPFS_VNODE_ALLOCATING) == 0) { 1542 TMPFS_NODE_UNLOCK(node); 1543 TMPFS_LOCK(tmp); 1544 tm_locked = true; 1545 goto relock; 1546 } 1547 tmpfs_free_vp(vp); 1548 1549 /* 1550 * If the node referenced by this vnode was deleted by the user, 1551 * we must free its associated data structures (now that the vnode 1552 * is being reclaimed). 1553 */ 1554 if (node->tn_links == 0 && 1555 (node->tn_vpstate & TMPFS_VNODE_ALLOCATING) == 0) { 1556 MPASS(tm_locked); 1557 node->tn_vpstate = TMPFS_VNODE_DOOMED; 1558 unlock = !tmpfs_free_node_locked(tmp, node, true); 1559 } else { 1560 unlock = true; 1561 } 1562 1563 if (unlock) { 1564 TMPFS_NODE_UNLOCK(node); 1565 if (tm_locked) 1566 TMPFS_UNLOCK(tmp); 1567 } 1568 1569 MPASS(vp->v_data == NULL); 1570 return (0); 1571 } 1572 1573 int 1574 tmpfs_print(struct vop_print_args *v) 1575 { 1576 struct vnode *vp = v->a_vp; 1577 1578 struct tmpfs_node *node; 1579 1580 node = VP_TO_TMPFS_NODE(vp); 1581 1582 printf("tag VT_TMPFS, tmpfs_node %p, flags 0x%lx, links %jd\n", 1583 node, node->tn_flags, (uintmax_t)node->tn_links); 1584 printf("\tmode 0%o, owner %d, group %d, size %jd, status 0x%x\n", 1585 node->tn_mode, node->tn_uid, node->tn_gid, 1586 (intmax_t)node->tn_size, node->tn_status); 1587 1588 if (vp->v_type == VFIFO) 1589 fifo_printinfo(vp); 1590 1591 printf("\n"); 1592 1593 return 0; 1594 } 1595 1596 int 1597 tmpfs_pathconf(struct vop_pathconf_args *v) 1598 { 1599 struct vnode *vp = v->a_vp; 1600 int name = v->a_name; 1601 long *retval = v->a_retval; 1602 1603 int error; 1604 1605 error = 0; 1606 1607 switch (name) { 1608 case _PC_LINK_MAX: 1609 *retval = TMPFS_LINK_MAX; 1610 break; 1611 1612 case _PC_SYMLINK_MAX: 1613 *retval = MAXPATHLEN; 1614 break; 1615 1616 case _PC_NAME_MAX: 1617 *retval = NAME_MAX; 1618 break; 1619 1620 case _PC_PIPE_BUF: 1621 if (vp->v_type == VDIR || vp->v_type == VFIFO) 1622 *retval = PIPE_BUF; 1623 else 1624 error = EINVAL; 1625 break; 1626 1627 case _PC_CHOWN_RESTRICTED: 1628 *retval = 1; 1629 break; 1630 1631 case _PC_NO_TRUNC: 1632 *retval = 1; 1633 break; 1634 1635 case _PC_SYNC_IO: 1636 *retval = 1; 1637 break; 1638 1639 case _PC_FILESIZEBITS: 1640 *retval = 64; 1641 break; 1642 1643 default: 1644 error = vop_stdpathconf(v); 1645 } 1646 1647 return error; 1648 } 1649 1650 static int 1651 tmpfs_vptofh(struct vop_vptofh_args *ap) 1652 /* 1653 vop_vptofh { 1654 IN struct vnode *a_vp; 1655 IN struct fid *a_fhp; 1656 }; 1657 */ 1658 { 1659 struct tmpfs_fid_data tfd; 1660 struct tmpfs_node *node; 1661 struct fid *fhp; 1662 1663 node = VP_TO_TMPFS_NODE(ap->a_vp); 1664 fhp = ap->a_fhp; 1665 fhp->fid_len = sizeof(tfd); 1666 1667 /* 1668 * Copy into fid_data from the stack to avoid unaligned pointer use. 1669 * See the comment in sys/mount.h on struct fid for details. 1670 */ 1671 tfd.tfd_id = node->tn_id; 1672 tfd.tfd_gen = node->tn_gen; 1673 memcpy(fhp->fid_data, &tfd, fhp->fid_len); 1674 1675 return (0); 1676 } 1677 1678 static int 1679 tmpfs_whiteout(struct vop_whiteout_args *ap) 1680 { 1681 struct vnode *dvp = ap->a_dvp; 1682 struct componentname *cnp = ap->a_cnp; 1683 struct tmpfs_dirent *de; 1684 1685 switch (ap->a_flags) { 1686 case LOOKUP: 1687 return (0); 1688 case CREATE: 1689 de = tmpfs_dir_lookup(VP_TO_TMPFS_DIR(dvp), NULL, cnp); 1690 if (de != NULL) 1691 return (de->td_node == NULL ? 0 : EEXIST); 1692 return (tmpfs_dir_whiteout_add(dvp, cnp)); 1693 case DELETE: 1694 tmpfs_dir_whiteout_remove(dvp, cnp); 1695 return (0); 1696 default: 1697 panic("tmpfs_whiteout: unknown op"); 1698 } 1699 } 1700 1701 static int 1702 tmpfs_vptocnp_dir(struct tmpfs_node *tn, struct tmpfs_node *tnp, 1703 struct tmpfs_dirent **pde) 1704 { 1705 struct tmpfs_dir_cursor dc; 1706 struct tmpfs_dirent *de; 1707 1708 for (de = tmpfs_dir_first(tnp, &dc); de != NULL; 1709 de = tmpfs_dir_next(tnp, &dc)) { 1710 if (de->td_node == tn) { 1711 *pde = de; 1712 return (0); 1713 } 1714 } 1715 return (ENOENT); 1716 } 1717 1718 static int 1719 tmpfs_vptocnp_fill(struct vnode *vp, struct tmpfs_node *tn, 1720 struct tmpfs_node *tnp, char *buf, size_t *buflen, struct vnode **dvp) 1721 { 1722 struct tmpfs_dirent *de; 1723 int error, i; 1724 1725 error = vn_vget_ino_gen(vp, tmpfs_vn_get_ino_alloc, tnp, LK_SHARED, 1726 dvp); 1727 if (error != 0) 1728 return (error); 1729 error = tmpfs_vptocnp_dir(tn, tnp, &de); 1730 if (error == 0) { 1731 i = *buflen; 1732 i -= de->td_namelen; 1733 if (i < 0) { 1734 error = ENOMEM; 1735 } else { 1736 bcopy(de->ud.td_name, buf + i, de->td_namelen); 1737 *buflen = i; 1738 } 1739 } 1740 if (error == 0) { 1741 if (vp != *dvp) 1742 VOP_UNLOCK(*dvp); 1743 } else { 1744 if (vp != *dvp) 1745 vput(*dvp); 1746 else 1747 vrele(vp); 1748 } 1749 return (error); 1750 } 1751 1752 static int 1753 tmpfs_vptocnp(struct vop_vptocnp_args *ap) 1754 { 1755 struct vnode *vp, **dvp; 1756 struct tmpfs_node *tn, *tnp, *tnp1; 1757 struct tmpfs_dirent *de; 1758 struct tmpfs_mount *tm; 1759 char *buf; 1760 size_t *buflen; 1761 int error; 1762 1763 vp = ap->a_vp; 1764 dvp = ap->a_vpp; 1765 buf = ap->a_buf; 1766 buflen = ap->a_buflen; 1767 1768 tm = VFS_TO_TMPFS(vp->v_mount); 1769 tn = VP_TO_TMPFS_NODE(vp); 1770 if (tn->tn_type == VDIR) { 1771 tnp = tn->tn_dir.tn_parent; 1772 if (tnp == NULL) 1773 return (ENOENT); 1774 tmpfs_ref_node(tnp); 1775 error = tmpfs_vptocnp_fill(vp, tn, tn->tn_dir.tn_parent, buf, 1776 buflen, dvp); 1777 tmpfs_free_node(tm, tnp); 1778 return (error); 1779 } 1780 restart: 1781 TMPFS_LOCK(tm); 1782 restart_locked: 1783 LIST_FOREACH_SAFE(tnp, &tm->tm_nodes_used, tn_entries, tnp1) { 1784 if (tnp->tn_type != VDIR) 1785 continue; 1786 TMPFS_NODE_LOCK(tnp); 1787 tmpfs_ref_node(tnp); 1788 1789 /* 1790 * tn_vnode cannot be instantiated while we hold the 1791 * node lock, so the directory cannot be changed while 1792 * we iterate over it. Do this to avoid instantiating 1793 * vnode for directories which cannot point to our 1794 * node. 1795 */ 1796 error = tnp->tn_vnode == NULL ? tmpfs_vptocnp_dir(tn, tnp, 1797 &de) : 0; 1798 1799 if (error == 0) { 1800 TMPFS_NODE_UNLOCK(tnp); 1801 TMPFS_UNLOCK(tm); 1802 error = tmpfs_vptocnp_fill(vp, tn, tnp, buf, buflen, 1803 dvp); 1804 if (error == 0) { 1805 tmpfs_free_node(tm, tnp); 1806 return (0); 1807 } 1808 if (VN_IS_DOOMED(vp)) { 1809 tmpfs_free_node(tm, tnp); 1810 return (ENOENT); 1811 } 1812 TMPFS_LOCK(tm); 1813 TMPFS_NODE_LOCK(tnp); 1814 } 1815 if (tmpfs_free_node_locked(tm, tnp, false)) { 1816 goto restart; 1817 } else { 1818 KASSERT(tnp->tn_refcount > 0, 1819 ("node %p refcount zero", tnp)); 1820 if (tnp->tn_attached) { 1821 tnp1 = LIST_NEXT(tnp, tn_entries); 1822 TMPFS_NODE_UNLOCK(tnp); 1823 } else { 1824 TMPFS_NODE_UNLOCK(tnp); 1825 goto restart_locked; 1826 } 1827 } 1828 } 1829 TMPFS_UNLOCK(tm); 1830 return (ENOENT); 1831 } 1832 1833 /* 1834 * Vnode operations vector used for files stored in a tmpfs file system. 1835 */ 1836 struct vop_vector tmpfs_vnodeop_entries = { 1837 .vop_default = &default_vnodeops, 1838 .vop_lookup = vfs_cache_lookup, 1839 .vop_cachedlookup = tmpfs_cached_lookup, 1840 .vop_create = tmpfs_create, 1841 .vop_mknod = tmpfs_mknod, 1842 .vop_open = tmpfs_open, 1843 .vop_close = tmpfs_close, 1844 .vop_fplookup_vexec = tmpfs_fplookup_vexec, 1845 .vop_fplookup_symlink = tmpfs_fplookup_symlink, 1846 .vop_access = tmpfs_access, 1847 .vop_stat = tmpfs_stat, 1848 .vop_getattr = tmpfs_getattr, 1849 .vop_setattr = tmpfs_setattr, 1850 .vop_read = tmpfs_read, 1851 .vop_read_pgcache = tmpfs_read_pgcache, 1852 .vop_write = tmpfs_write, 1853 .vop_fsync = tmpfs_fsync, 1854 .vop_remove = tmpfs_remove, 1855 .vop_link = tmpfs_link, 1856 .vop_rename = tmpfs_rename, 1857 .vop_mkdir = tmpfs_mkdir, 1858 .vop_rmdir = tmpfs_rmdir, 1859 .vop_symlink = tmpfs_symlink, 1860 .vop_readdir = tmpfs_readdir, 1861 .vop_readlink = tmpfs_readlink, 1862 .vop_inactive = tmpfs_inactive, 1863 .vop_need_inactive = tmpfs_need_inactive, 1864 .vop_reclaim = tmpfs_reclaim, 1865 .vop_print = tmpfs_print, 1866 .vop_pathconf = tmpfs_pathconf, 1867 .vop_vptofh = tmpfs_vptofh, 1868 .vop_whiteout = tmpfs_whiteout, 1869 .vop_bmap = VOP_EOPNOTSUPP, 1870 .vop_vptocnp = tmpfs_vptocnp, 1871 .vop_lock1 = vop_lock, 1872 .vop_unlock = vop_unlock, 1873 .vop_islocked = vop_islocked, 1874 }; 1875 VFS_VOP_VECTOR_REGISTER(tmpfs_vnodeop_entries); 1876 1877 /* 1878 * Same vector for mounts which do not use namecache. 1879 */ 1880 struct vop_vector tmpfs_vnodeop_nonc_entries = { 1881 .vop_default = &tmpfs_vnodeop_entries, 1882 .vop_lookup = tmpfs_lookup, 1883 }; 1884 VFS_VOP_VECTOR_REGISTER(tmpfs_vnodeop_nonc_entries); 1885