1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 /* 22 * Copyright 2007 Sun Microsystems, Inc. All rights reserved. 23 * Use is subject to license terms. 24 */ 25 26 /* Portions Copyright 2007 Jeremy Teo */ 27 28 #pragma ident "%Z%%M% %I% %E% SMI" 29 30 #include <sys/types.h> 31 #include <sys/param.h> 32 #include <sys/time.h> 33 #include <sys/systm.h> 34 #include <sys/sysmacros.h> 35 #include <sys/resource.h> 36 #include <sys/vfs.h> 37 #include <sys/vfs_opreg.h> 38 #include <sys/vnode.h> 39 #include <sys/file.h> 40 #include <sys/stat.h> 41 #include <sys/kmem.h> 42 #include <sys/taskq.h> 43 #include <sys/uio.h> 44 #include <sys/vmsystm.h> 45 #include <sys/atomic.h> 46 #include <sys/vm.h> 47 #include <vm/seg_vn.h> 48 #include <vm/pvn.h> 49 #include <vm/as.h> 50 #include <sys/mman.h> 51 #include <sys/pathname.h> 52 #include <sys/cmn_err.h> 53 #include <sys/errno.h> 54 #include <sys/unistd.h> 55 #include <sys/zfs_vfsops.h> 56 #include <sys/zfs_dir.h> 57 #include <sys/zfs_acl.h> 58 #include <sys/zfs_ioctl.h> 59 #include <sys/fs/zfs.h> 60 #include <sys/dmu.h> 61 #include <sys/spa.h> 62 #include <sys/txg.h> 63 #include <sys/dbuf.h> 64 #include <sys/zap.h> 65 #include <sys/dirent.h> 66 #include <sys/policy.h> 67 #include <sys/sunddi.h> 68 #include <sys/filio.h> 69 #include "fs/fs_subr.h" 70 #include <sys/zfs_ctldir.h> 71 #include <sys/dnlc.h> 72 #include <sys/zfs_rlock.h> 73 74 /* 75 * Programming rules. 76 * 77 * Each vnode op performs some logical unit of work. To do this, the ZPL must 78 * properly lock its in-core state, create a DMU transaction, do the work, 79 * record this work in the intent log (ZIL), commit the DMU transaction, 80 * and wait the the intent log to commit if it's is a synchronous operation. 81 * Morover, the vnode ops must work in both normal and log replay context. 82 * The ordering of events is important to avoid deadlocks and references 83 * to freed memory. The example below illustrates the following Big Rules: 84 * 85 * (1) A check must be made in each zfs thread for a mounted file system. 86 * This is done avoiding races using ZFS_ENTER(zfsvfs) or 87 * ZFS_ENTER_VERIFY(zfsvfs, zp). A ZFS_EXIT(zfsvfs) is needed before 88 * all returns. 89 * 90 * (2) VN_RELE() should always be the last thing except for zil_commit() 91 * (if necessary) and ZFS_EXIT(). This is for 3 reasons: 92 * First, if it's the last reference, the vnode/znode 93 * can be freed, so the zp may point to freed memory. Second, the last 94 * reference will call zfs_zinactive(), which may induce a lot of work -- 95 * pushing cached pages (which acquires range locks) and syncing out 96 * cached atime changes. Third, zfs_zinactive() may require a new tx, 97 * which could deadlock the system if you were already holding one. 98 * 99 * (3) All range locks must be grabbed before calling dmu_tx_assign(), 100 * as they can span dmu_tx_assign() calls. 101 * 102 * (4) Always pass zfsvfs->z_assign as the second argument to dmu_tx_assign(). 103 * In normal operation, this will be TXG_NOWAIT. During ZIL replay, 104 * it will be a specific txg. Either way, dmu_tx_assign() never blocks. 105 * This is critical because we don't want to block while holding locks. 106 * Note, in particular, that if a lock is sometimes acquired before 107 * the tx assigns, and sometimes after (e.g. z_lock), then failing to 108 * use a non-blocking assign can deadlock the system. The scenario: 109 * 110 * Thread A has grabbed a lock before calling dmu_tx_assign(). 111 * Thread B is in an already-assigned tx, and blocks for this lock. 112 * Thread A calls dmu_tx_assign(TXG_WAIT) and blocks in txg_wait_open() 113 * forever, because the previous txg can't quiesce until B's tx commits. 114 * 115 * If dmu_tx_assign() returns ERESTART and zfsvfs->z_assign is TXG_NOWAIT, 116 * then drop all locks, call dmu_tx_wait(), and try again. 117 * 118 * (5) If the operation succeeded, generate the intent log entry for it 119 * before dropping locks. This ensures that the ordering of events 120 * in the intent log matches the order in which they actually occurred. 121 * 122 * (6) At the end of each vnode op, the DMU tx must always commit, 123 * regardless of whether there were any errors. 124 * 125 * (7) After dropping all locks, invoke zil_commit(zilog, seq, foid) 126 * to ensure that synchronous semantics are provided when necessary. 127 * 128 * In general, this is how things should be ordered in each vnode op: 129 * 130 * ZFS_ENTER(zfsvfs); // exit if unmounted 131 * top: 132 * zfs_dirent_lock(&dl, ...) // lock directory entry (may VN_HOLD()) 133 * rw_enter(...); // grab any other locks you need 134 * tx = dmu_tx_create(...); // get DMU tx 135 * dmu_tx_hold_*(); // hold each object you might modify 136 * error = dmu_tx_assign(tx, zfsvfs->z_assign); // try to assign 137 * if (error) { 138 * rw_exit(...); // drop locks 139 * zfs_dirent_unlock(dl); // unlock directory entry 140 * VN_RELE(...); // release held vnodes 141 * if (error == ERESTART && zfsvfs->z_assign == TXG_NOWAIT) { 142 * dmu_tx_wait(tx); 143 * dmu_tx_abort(tx); 144 * goto top; 145 * } 146 * dmu_tx_abort(tx); // abort DMU tx 147 * ZFS_EXIT(zfsvfs); // finished in zfs 148 * return (error); // really out of space 149 * } 150 * error = do_real_work(); // do whatever this VOP does 151 * if (error == 0) 152 * zfs_log_*(...); // on success, make ZIL entry 153 * dmu_tx_commit(tx); // commit DMU tx -- error or not 154 * rw_exit(...); // drop locks 155 * zfs_dirent_unlock(dl); // unlock directory entry 156 * VN_RELE(...); // release held vnodes 157 * zil_commit(zilog, seq, foid); // synchronous when necessary 158 * ZFS_EXIT(zfsvfs); // finished in zfs 159 * return (error); // done, report error 160 */ 161 /* ARGSUSED */ 162 static int 163 zfs_open(vnode_t **vpp, int flag, cred_t *cr) 164 { 165 znode_t *zp = VTOZ(*vpp); 166 167 /* Keep a count of the synchronous opens in the znode */ 168 if (flag & (FSYNC | FDSYNC)) 169 atomic_inc_32(&zp->z_sync_cnt); 170 return (0); 171 } 172 173 /* ARGSUSED */ 174 static int 175 zfs_close(vnode_t *vp, int flag, int count, offset_t offset, cred_t *cr) 176 { 177 znode_t *zp = VTOZ(vp); 178 179 /* Decrement the synchronous opens in the znode */ 180 if ((flag & (FSYNC | FDSYNC)) && (count == 1)) 181 atomic_dec_32(&zp->z_sync_cnt); 182 183 /* 184 * Clean up any locks held by this process on the vp. 185 */ 186 cleanlocks(vp, ddi_get_pid(), 0); 187 cleanshares(vp, ddi_get_pid()); 188 189 return (0); 190 } 191 192 /* 193 * Lseek support for finding holes (cmd == _FIO_SEEK_HOLE) and 194 * data (cmd == _FIO_SEEK_DATA). "off" is an in/out parameter. 195 */ 196 static int 197 zfs_holey(vnode_t *vp, int cmd, offset_t *off) 198 { 199 znode_t *zp = VTOZ(vp); 200 uint64_t noff = (uint64_t)*off; /* new offset */ 201 uint64_t file_sz; 202 int error; 203 boolean_t hole; 204 205 file_sz = zp->z_phys->zp_size; 206 if (noff >= file_sz) { 207 return (ENXIO); 208 } 209 210 if (cmd == _FIO_SEEK_HOLE) 211 hole = B_TRUE; 212 else 213 hole = B_FALSE; 214 215 error = dmu_offset_next(zp->z_zfsvfs->z_os, zp->z_id, hole, &noff); 216 217 /* end of file? */ 218 if ((error == ESRCH) || (noff > file_sz)) { 219 /* 220 * Handle the virtual hole at the end of file. 221 */ 222 if (hole) { 223 *off = file_sz; 224 return (0); 225 } 226 return (ENXIO); 227 } 228 229 if (noff < *off) 230 return (error); 231 *off = noff; 232 return (error); 233 } 234 235 /* ARGSUSED */ 236 static int 237 zfs_ioctl(vnode_t *vp, int com, intptr_t data, int flag, cred_t *cred, 238 int *rvalp) 239 { 240 offset_t off; 241 int error; 242 zfsvfs_t *zfsvfs; 243 znode_t *zp; 244 245 switch (com) { 246 case _FIOFFS: 247 return (zfs_sync(vp->v_vfsp, 0, cred)); 248 249 /* 250 * The following two ioctls are used by bfu. Faking out, 251 * necessary to avoid bfu errors. 252 */ 253 case _FIOGDIO: 254 case _FIOSDIO: 255 return (0); 256 257 case _FIO_SEEK_DATA: 258 case _FIO_SEEK_HOLE: 259 if (ddi_copyin((void *)data, &off, sizeof (off), flag)) 260 return (EFAULT); 261 262 zp = VTOZ(vp); 263 zfsvfs = zp->z_zfsvfs; 264 ZFS_ENTER_VERIFY_ZP(zfsvfs, zp); 265 266 /* offset parameter is in/out */ 267 error = zfs_holey(vp, com, &off); 268 ZFS_EXIT(zfsvfs); 269 if (error) 270 return (error); 271 if (ddi_copyout(&off, (void *)data, sizeof (off), flag)) 272 return (EFAULT); 273 return (0); 274 } 275 return (ENOTTY); 276 } 277 278 /* 279 * When a file is memory mapped, we must keep the IO data synchronized 280 * between the DMU cache and the memory mapped pages. What this means: 281 * 282 * On Write: If we find a memory mapped page, we write to *both* 283 * the page and the dmu buffer. 284 * 285 * NOTE: We will always "break up" the IO into PAGESIZE uiomoves when 286 * the file is memory mapped. 287 */ 288 static int 289 mappedwrite(vnode_t *vp, int nbytes, uio_t *uio, dmu_tx_t *tx) 290 { 291 znode_t *zp = VTOZ(vp); 292 zfsvfs_t *zfsvfs = zp->z_zfsvfs; 293 int64_t start, off; 294 int len = nbytes; 295 int error = 0; 296 297 start = uio->uio_loffset; 298 off = start & PAGEOFFSET; 299 for (start &= PAGEMASK; len > 0; start += PAGESIZE) { 300 page_t *pp; 301 uint64_t bytes = MIN(PAGESIZE - off, len); 302 uint64_t woff = uio->uio_loffset; 303 304 /* 305 * We don't want a new page to "appear" in the middle of 306 * the file update (because it may not get the write 307 * update data), so we grab a lock to block 308 * zfs_getpage(). 309 */ 310 rw_enter(&zp->z_map_lock, RW_WRITER); 311 if (pp = page_lookup(vp, start, SE_SHARED)) { 312 caddr_t va; 313 314 rw_exit(&zp->z_map_lock); 315 va = ppmapin(pp, PROT_READ | PROT_WRITE, (caddr_t)-1L); 316 error = uiomove(va+off, bytes, UIO_WRITE, uio); 317 if (error == 0) { 318 dmu_write(zfsvfs->z_os, zp->z_id, 319 woff, bytes, va+off, tx); 320 } 321 ppmapout(va); 322 page_unlock(pp); 323 } else { 324 error = dmu_write_uio(zfsvfs->z_os, zp->z_id, 325 uio, bytes, tx); 326 rw_exit(&zp->z_map_lock); 327 } 328 len -= bytes; 329 off = 0; 330 if (error) 331 break; 332 } 333 return (error); 334 } 335 336 /* 337 * When a file is memory mapped, we must keep the IO data synchronized 338 * between the DMU cache and the memory mapped pages. What this means: 339 * 340 * On Read: We "read" preferentially from memory mapped pages, 341 * else we default from the dmu buffer. 342 * 343 * NOTE: We will always "break up" the IO into PAGESIZE uiomoves when 344 * the file is memory mapped. 345 */ 346 static int 347 mappedread(vnode_t *vp, int nbytes, uio_t *uio) 348 { 349 znode_t *zp = VTOZ(vp); 350 objset_t *os = zp->z_zfsvfs->z_os; 351 int64_t start, off; 352 int len = nbytes; 353 int error = 0; 354 355 start = uio->uio_loffset; 356 off = start & PAGEOFFSET; 357 for (start &= PAGEMASK; len > 0; start += PAGESIZE) { 358 page_t *pp; 359 uint64_t bytes = MIN(PAGESIZE - off, len); 360 361 if (pp = page_lookup(vp, start, SE_SHARED)) { 362 caddr_t va; 363 364 va = ppmapin(pp, PROT_READ, (caddr_t)-1L); 365 error = uiomove(va + off, bytes, UIO_READ, uio); 366 ppmapout(va); 367 page_unlock(pp); 368 } else { 369 error = dmu_read_uio(os, zp->z_id, uio, bytes); 370 } 371 len -= bytes; 372 off = 0; 373 if (error) 374 break; 375 } 376 return (error); 377 } 378 379 offset_t zfs_read_chunk_size = 1024 * 1024; /* Tunable */ 380 381 /* 382 * Read bytes from specified file into supplied buffer. 383 * 384 * IN: vp - vnode of file to be read from. 385 * uio - structure supplying read location, range info, 386 * and return buffer. 387 * ioflag - SYNC flags; used to provide FRSYNC semantics. 388 * cr - credentials of caller. 389 * 390 * OUT: uio - updated offset and range, buffer filled. 391 * 392 * RETURN: 0 if success 393 * error code if failure 394 * 395 * Side Effects: 396 * vp - atime updated if byte count > 0 397 */ 398 /* ARGSUSED */ 399 static int 400 zfs_read(vnode_t *vp, uio_t *uio, int ioflag, cred_t *cr, caller_context_t *ct) 401 { 402 znode_t *zp = VTOZ(vp); 403 zfsvfs_t *zfsvfs = zp->z_zfsvfs; 404 objset_t *os; 405 ssize_t n, nbytes; 406 int error; 407 rl_t *rl; 408 409 ZFS_ENTER_VERIFY_ZP(zfsvfs, zp); 410 os = zfsvfs->z_os; 411 412 /* 413 * Validate file offset 414 */ 415 if (uio->uio_loffset < (offset_t)0) { 416 ZFS_EXIT(zfsvfs); 417 return (EINVAL); 418 } 419 420 /* 421 * Fasttrack empty reads 422 */ 423 if (uio->uio_resid == 0) { 424 ZFS_EXIT(zfsvfs); 425 return (0); 426 } 427 428 /* 429 * Check for mandatory locks 430 */ 431 if (MANDMODE((mode_t)zp->z_phys->zp_mode)) { 432 if (error = chklock(vp, FREAD, 433 uio->uio_loffset, uio->uio_resid, uio->uio_fmode, ct)) { 434 ZFS_EXIT(zfsvfs); 435 return (error); 436 } 437 } 438 439 /* 440 * If we're in FRSYNC mode, sync out this znode before reading it. 441 */ 442 if (ioflag & FRSYNC) 443 zil_commit(zfsvfs->z_log, zp->z_last_itx, zp->z_id); 444 445 /* 446 * Lock the range against changes. 447 */ 448 rl = zfs_range_lock(zp, uio->uio_loffset, uio->uio_resid, RL_READER); 449 450 /* 451 * If we are reading past end-of-file we can skip 452 * to the end; but we might still need to set atime. 453 */ 454 if (uio->uio_loffset >= zp->z_phys->zp_size) { 455 error = 0; 456 goto out; 457 } 458 459 ASSERT(uio->uio_loffset < zp->z_phys->zp_size); 460 n = MIN(uio->uio_resid, zp->z_phys->zp_size - uio->uio_loffset); 461 462 while (n > 0) { 463 nbytes = MIN(n, zfs_read_chunk_size - 464 P2PHASE(uio->uio_loffset, zfs_read_chunk_size)); 465 466 if (vn_has_cached_data(vp)) 467 error = mappedread(vp, nbytes, uio); 468 else 469 error = dmu_read_uio(os, zp->z_id, uio, nbytes); 470 if (error) 471 break; 472 473 n -= nbytes; 474 } 475 476 out: 477 zfs_range_unlock(rl); 478 479 ZFS_ACCESSTIME_STAMP(zfsvfs, zp); 480 ZFS_EXIT(zfsvfs); 481 return (error); 482 } 483 484 /* 485 * Fault in the pages of the first n bytes specified by the uio structure. 486 * 1 byte in each page is touched and the uio struct is unmodified. 487 * Any error will exit this routine as this is only a best 488 * attempt to get the pages resident. This is a copy of ufs_trans_touch(). 489 */ 490 static void 491 zfs_prefault_write(ssize_t n, struct uio *uio) 492 { 493 struct iovec *iov; 494 ulong_t cnt, incr; 495 caddr_t p; 496 uint8_t tmp; 497 498 iov = uio->uio_iov; 499 500 while (n) { 501 cnt = MIN(iov->iov_len, n); 502 if (cnt == 0) { 503 /* empty iov entry */ 504 iov++; 505 continue; 506 } 507 n -= cnt; 508 /* 509 * touch each page in this segment. 510 */ 511 p = iov->iov_base; 512 while (cnt) { 513 switch (uio->uio_segflg) { 514 case UIO_USERSPACE: 515 case UIO_USERISPACE: 516 if (fuword8(p, &tmp)) 517 return; 518 break; 519 case UIO_SYSSPACE: 520 if (kcopy(p, &tmp, 1)) 521 return; 522 break; 523 } 524 incr = MIN(cnt, PAGESIZE); 525 p += incr; 526 cnt -= incr; 527 } 528 /* 529 * touch the last byte in case it straddles a page. 530 */ 531 p--; 532 switch (uio->uio_segflg) { 533 case UIO_USERSPACE: 534 case UIO_USERISPACE: 535 if (fuword8(p, &tmp)) 536 return; 537 break; 538 case UIO_SYSSPACE: 539 if (kcopy(p, &tmp, 1)) 540 return; 541 break; 542 } 543 iov++; 544 } 545 } 546 547 /* 548 * Write the bytes to a file. 549 * 550 * IN: vp - vnode of file to be written to. 551 * uio - structure supplying write location, range info, 552 * and data buffer. 553 * ioflag - FAPPEND flag set if in append mode. 554 * cr - credentials of caller. 555 * 556 * OUT: uio - updated offset and range. 557 * 558 * RETURN: 0 if success 559 * error code if failure 560 * 561 * Timestamps: 562 * vp - ctime|mtime updated if byte count > 0 563 */ 564 /* ARGSUSED */ 565 static int 566 zfs_write(vnode_t *vp, uio_t *uio, int ioflag, cred_t *cr, caller_context_t *ct) 567 { 568 znode_t *zp = VTOZ(vp); 569 rlim64_t limit = uio->uio_llimit; 570 ssize_t start_resid = uio->uio_resid; 571 ssize_t tx_bytes; 572 uint64_t end_size; 573 dmu_tx_t *tx; 574 zfsvfs_t *zfsvfs = zp->z_zfsvfs; 575 zilog_t *zilog; 576 offset_t woff; 577 ssize_t n, nbytes; 578 rl_t *rl; 579 int max_blksz = zfsvfs->z_max_blksz; 580 int error; 581 582 /* 583 * Fasttrack empty write 584 */ 585 n = start_resid; 586 if (n == 0) 587 return (0); 588 589 if (limit == RLIM64_INFINITY || limit > MAXOFFSET_T) 590 limit = MAXOFFSET_T; 591 592 ZFS_ENTER_VERIFY_ZP(zfsvfs, zp); 593 zilog = zfsvfs->z_log; 594 595 /* 596 * Pre-fault the pages to ensure slow (eg NFS) pages 597 * don't hold up txg. 598 */ 599 zfs_prefault_write(n, uio); 600 601 /* 602 * If in append mode, set the io offset pointer to eof. 603 */ 604 if (ioflag & FAPPEND) { 605 /* 606 * Range lock for a file append: 607 * The value for the start of range will be determined by 608 * zfs_range_lock() (to guarantee append semantics). 609 * If this write will cause the block size to increase, 610 * zfs_range_lock() will lock the entire file, so we must 611 * later reduce the range after we grow the block size. 612 */ 613 rl = zfs_range_lock(zp, 0, n, RL_APPEND); 614 if (rl->r_len == UINT64_MAX) { 615 /* overlocked, zp_size can't change */ 616 woff = uio->uio_loffset = zp->z_phys->zp_size; 617 } else { 618 woff = uio->uio_loffset = rl->r_off; 619 } 620 } else { 621 woff = uio->uio_loffset; 622 /* 623 * Validate file offset 624 */ 625 if (woff < 0) { 626 ZFS_EXIT(zfsvfs); 627 return (EINVAL); 628 } 629 630 /* 631 * If we need to grow the block size then zfs_range_lock() 632 * will lock a wider range than we request here. 633 * Later after growing the block size we reduce the range. 634 */ 635 rl = zfs_range_lock(zp, woff, n, RL_WRITER); 636 } 637 638 if (woff >= limit) { 639 zfs_range_unlock(rl); 640 ZFS_EXIT(zfsvfs); 641 return (EFBIG); 642 } 643 644 if ((woff + n) > limit || woff > (limit - n)) 645 n = limit - woff; 646 647 /* 648 * Check for mandatory locks 649 */ 650 if (MANDMODE((mode_t)zp->z_phys->zp_mode) && 651 (error = chklock(vp, FWRITE, woff, n, uio->uio_fmode, ct)) != 0) { 652 zfs_range_unlock(rl); 653 ZFS_EXIT(zfsvfs); 654 return (error); 655 } 656 end_size = MAX(zp->z_phys->zp_size, woff + n); 657 658 /* 659 * Write the file in reasonable size chunks. Each chunk is written 660 * in a separate transaction; this keeps the intent log records small 661 * and allows us to do more fine-grained space accounting. 662 */ 663 while (n > 0) { 664 /* 665 * Start a transaction. 666 */ 667 woff = uio->uio_loffset; 668 tx = dmu_tx_create(zfsvfs->z_os); 669 dmu_tx_hold_bonus(tx, zp->z_id); 670 dmu_tx_hold_write(tx, zp->z_id, woff, MIN(n, max_blksz)); 671 error = dmu_tx_assign(tx, zfsvfs->z_assign); 672 if (error) { 673 if (error == ERESTART && 674 zfsvfs->z_assign == TXG_NOWAIT) { 675 dmu_tx_wait(tx); 676 dmu_tx_abort(tx); 677 continue; 678 } 679 dmu_tx_abort(tx); 680 break; 681 } 682 683 /* 684 * If zfs_range_lock() over-locked we grow the blocksize 685 * and then reduce the lock range. This will only happen 686 * on the first iteration since zfs_range_reduce() will 687 * shrink down r_len to the appropriate size. 688 */ 689 if (rl->r_len == UINT64_MAX) { 690 uint64_t new_blksz; 691 692 if (zp->z_blksz > max_blksz) { 693 ASSERT(!ISP2(zp->z_blksz)); 694 new_blksz = MIN(end_size, SPA_MAXBLOCKSIZE); 695 } else { 696 new_blksz = MIN(end_size, max_blksz); 697 } 698 zfs_grow_blocksize(zp, new_blksz, tx); 699 zfs_range_reduce(rl, woff, n); 700 } 701 702 /* 703 * XXX - should we really limit each write to z_max_blksz? 704 * Perhaps we should use SPA_MAXBLOCKSIZE chunks? 705 */ 706 nbytes = MIN(n, max_blksz - P2PHASE(woff, max_blksz)); 707 rw_enter(&zp->z_map_lock, RW_READER); 708 709 tx_bytes = uio->uio_resid; 710 if (vn_has_cached_data(vp)) { 711 rw_exit(&zp->z_map_lock); 712 error = mappedwrite(vp, nbytes, uio, tx); 713 } else { 714 error = dmu_write_uio(zfsvfs->z_os, zp->z_id, 715 uio, nbytes, tx); 716 rw_exit(&zp->z_map_lock); 717 } 718 tx_bytes -= uio->uio_resid; 719 720 /* 721 * If we made no progress, we're done. If we made even 722 * partial progress, update the znode and ZIL accordingly. 723 */ 724 if (tx_bytes == 0) { 725 dmu_tx_commit(tx); 726 ASSERT(error != 0); 727 break; 728 } 729 730 /* 731 * Clear Set-UID/Set-GID bits on successful write if not 732 * privileged and at least one of the excute bits is set. 733 * 734 * It would be nice to to this after all writes have 735 * been done, but that would still expose the ISUID/ISGID 736 * to another app after the partial write is committed. 737 */ 738 mutex_enter(&zp->z_acl_lock); 739 if ((zp->z_phys->zp_mode & (S_IXUSR | (S_IXUSR >> 3) | 740 (S_IXUSR >> 6))) != 0 && 741 (zp->z_phys->zp_mode & (S_ISUID | S_ISGID)) != 0 && 742 secpolicy_vnode_setid_retain(cr, 743 (zp->z_phys->zp_mode & S_ISUID) != 0 && 744 zp->z_phys->zp_uid == 0) != 0) { 745 zp->z_phys->zp_mode &= ~(S_ISUID | S_ISGID); 746 } 747 mutex_exit(&zp->z_acl_lock); 748 749 /* 750 * Update time stamp. NOTE: This marks the bonus buffer as 751 * dirty, so we don't have to do it again for zp_size. 752 */ 753 zfs_time_stamper(zp, CONTENT_MODIFIED, tx); 754 755 /* 756 * Update the file size (zp_size) if it has changed; 757 * account for possible concurrent updates. 758 */ 759 while ((end_size = zp->z_phys->zp_size) < uio->uio_loffset) 760 (void) atomic_cas_64(&zp->z_phys->zp_size, end_size, 761 uio->uio_loffset); 762 zfs_log_write(zilog, tx, TX_WRITE, zp, woff, tx_bytes, ioflag); 763 dmu_tx_commit(tx); 764 765 if (error != 0) 766 break; 767 ASSERT(tx_bytes == nbytes); 768 n -= nbytes; 769 } 770 771 zfs_range_unlock(rl); 772 773 /* 774 * If we're in replay mode, or we made no progress, return error. 775 * Otherwise, it's at least a partial write, so it's successful. 776 */ 777 if (zfsvfs->z_assign >= TXG_INITIAL || uio->uio_resid == start_resid) { 778 ZFS_EXIT(zfsvfs); 779 return (error); 780 } 781 782 if (ioflag & (FSYNC | FDSYNC)) 783 zil_commit(zilog, zp->z_last_itx, zp->z_id); 784 785 ZFS_EXIT(zfsvfs); 786 return (0); 787 } 788 789 void 790 zfs_get_done(dmu_buf_t *db, void *vzgd) 791 { 792 zgd_t *zgd = (zgd_t *)vzgd; 793 rl_t *rl = zgd->zgd_rl; 794 vnode_t *vp = ZTOV(rl->r_zp); 795 796 dmu_buf_rele(db, vzgd); 797 zfs_range_unlock(rl); 798 VN_RELE(vp); 799 zil_add_vdev(zgd->zgd_zilog, DVA_GET_VDEV(BP_IDENTITY(zgd->zgd_bp))); 800 kmem_free(zgd, sizeof (zgd_t)); 801 } 802 803 /* 804 * Get data to generate a TX_WRITE intent log record. 805 */ 806 int 807 zfs_get_data(void *arg, lr_write_t *lr, char *buf, zio_t *zio) 808 { 809 zfsvfs_t *zfsvfs = arg; 810 objset_t *os = zfsvfs->z_os; 811 znode_t *zp; 812 uint64_t off = lr->lr_offset; 813 dmu_buf_t *db; 814 rl_t *rl; 815 zgd_t *zgd; 816 int dlen = lr->lr_length; /* length of user data */ 817 int error = 0; 818 819 ASSERT(zio); 820 ASSERT(dlen != 0); 821 822 /* 823 * Nothing to do if the file has been removed 824 */ 825 if (zfs_zget(zfsvfs, lr->lr_foid, &zp) != 0) 826 return (ENOENT); 827 if (zp->z_unlinked) { 828 VN_RELE(ZTOV(zp)); 829 return (ENOENT); 830 } 831 832 /* 833 * Write records come in two flavors: immediate and indirect. 834 * For small writes it's cheaper to store the data with the 835 * log record (immediate); for large writes it's cheaper to 836 * sync the data and get a pointer to it (indirect) so that 837 * we don't have to write the data twice. 838 */ 839 if (buf != NULL) { /* immediate write */ 840 rl = zfs_range_lock(zp, off, dlen, RL_READER); 841 /* test for truncation needs to be done while range locked */ 842 if (off >= zp->z_phys->zp_size) { 843 error = ENOENT; 844 goto out; 845 } 846 VERIFY(0 == dmu_read(os, lr->lr_foid, off, dlen, buf)); 847 } else { /* indirect write */ 848 uint64_t boff; /* block starting offset */ 849 850 /* 851 * Have to lock the whole block to ensure when it's 852 * written out and it's checksum is being calculated 853 * that no one can change the data. We need to re-check 854 * blocksize after we get the lock in case it's changed! 855 */ 856 for (;;) { 857 if (ISP2(zp->z_blksz)) { 858 boff = P2ALIGN_TYPED(off, zp->z_blksz, 859 uint64_t); 860 } else { 861 boff = 0; 862 } 863 dlen = zp->z_blksz; 864 rl = zfs_range_lock(zp, boff, dlen, RL_READER); 865 if (zp->z_blksz == dlen) 866 break; 867 zfs_range_unlock(rl); 868 } 869 /* test for truncation needs to be done while range locked */ 870 if (off >= zp->z_phys->zp_size) { 871 error = ENOENT; 872 goto out; 873 } 874 zgd = (zgd_t *)kmem_alloc(sizeof (zgd_t), KM_SLEEP); 875 zgd->zgd_rl = rl; 876 zgd->zgd_zilog = zfsvfs->z_log; 877 zgd->zgd_bp = &lr->lr_blkptr; 878 VERIFY(0 == dmu_buf_hold(os, lr->lr_foid, boff, zgd, &db)); 879 ASSERT(boff == db->db_offset); 880 lr->lr_blkoff = off - boff; 881 error = dmu_sync(zio, db, &lr->lr_blkptr, 882 lr->lr_common.lrc_txg, zfs_get_done, zgd); 883 ASSERT((error && error != EINPROGRESS) || 884 lr->lr_length <= zp->z_blksz); 885 if (error == 0) { 886 zil_add_vdev(zfsvfs->z_log, 887 DVA_GET_VDEV(BP_IDENTITY(&lr->lr_blkptr))); 888 } 889 /* 890 * If we get EINPROGRESS, then we need to wait for a 891 * write IO initiated by dmu_sync() to complete before 892 * we can release this dbuf. We will finish everything 893 * up in the zfs_get_done() callback. 894 */ 895 if (error == EINPROGRESS) 896 return (0); 897 dmu_buf_rele(db, zgd); 898 kmem_free(zgd, sizeof (zgd_t)); 899 } 900 out: 901 zfs_range_unlock(rl); 902 VN_RELE(ZTOV(zp)); 903 return (error); 904 } 905 906 /*ARGSUSED*/ 907 static int 908 zfs_access(vnode_t *vp, int mode, int flags, cred_t *cr) 909 { 910 znode_t *zp = VTOZ(vp); 911 zfsvfs_t *zfsvfs = zp->z_zfsvfs; 912 int error; 913 914 ZFS_ENTER_VERIFY_ZP(zfsvfs, zp); 915 error = zfs_zaccess_rwx(zp, mode, cr); 916 ZFS_EXIT(zfsvfs); 917 return (error); 918 } 919 920 /* 921 * Lookup an entry in a directory, or an extended attribute directory. 922 * If it exists, return a held vnode reference for it. 923 * 924 * IN: dvp - vnode of directory to search. 925 * nm - name of entry to lookup. 926 * pnp - full pathname to lookup [UNUSED]. 927 * flags - LOOKUP_XATTR set if looking for an attribute. 928 * rdir - root directory vnode [UNUSED]. 929 * cr - credentials of caller. 930 * 931 * OUT: vpp - vnode of located entry, NULL if not found. 932 * 933 * RETURN: 0 if success 934 * error code if failure 935 * 936 * Timestamps: 937 * NA 938 */ 939 /* ARGSUSED */ 940 static int 941 zfs_lookup(vnode_t *dvp, char *nm, vnode_t **vpp, struct pathname *pnp, 942 int flags, vnode_t *rdir, cred_t *cr) 943 { 944 945 znode_t *zdp = VTOZ(dvp); 946 zfsvfs_t *zfsvfs = zdp->z_zfsvfs; 947 int error; 948 949 ZFS_ENTER_VERIFY_ZP(zfsvfs, zdp); 950 951 *vpp = NULL; 952 953 if (flags & LOOKUP_XATTR) { 954 /* 955 * If the xattr property is off, refuse the lookup request. 956 */ 957 if (!(zfsvfs->z_vfs->vfs_flag & VFS_XATTR)) { 958 ZFS_EXIT(zfsvfs); 959 return (EINVAL); 960 } 961 962 /* 963 * We don't allow recursive attributes.. 964 * Maybe someday we will. 965 */ 966 if (zdp->z_phys->zp_flags & ZFS_XATTR) { 967 ZFS_EXIT(zfsvfs); 968 return (EINVAL); 969 } 970 971 if (error = zfs_get_xattrdir(VTOZ(dvp), vpp, cr, flags)) { 972 ZFS_EXIT(zfsvfs); 973 return (error); 974 } 975 976 /* 977 * Do we have permission to get into attribute directory? 978 */ 979 980 if (error = zfs_zaccess(VTOZ(*vpp), ACE_EXECUTE, cr)) { 981 VN_RELE(*vpp); 982 } 983 984 ZFS_EXIT(zfsvfs); 985 return (error); 986 } 987 988 if (dvp->v_type != VDIR) { 989 ZFS_EXIT(zfsvfs); 990 return (ENOTDIR); 991 } 992 993 /* 994 * Check accessibility of directory. 995 */ 996 997 if (error = zfs_zaccess(zdp, ACE_EXECUTE, cr)) { 998 ZFS_EXIT(zfsvfs); 999 return (error); 1000 } 1001 1002 if ((error = zfs_dirlook(zdp, nm, vpp)) == 0) { 1003 1004 /* 1005 * Convert device special files 1006 */ 1007 if (IS_DEVVP(*vpp)) { 1008 vnode_t *svp; 1009 1010 svp = specvp(*vpp, (*vpp)->v_rdev, (*vpp)->v_type, cr); 1011 VN_RELE(*vpp); 1012 if (svp == NULL) 1013 error = ENOSYS; 1014 else 1015 *vpp = svp; 1016 } 1017 } 1018 1019 ZFS_EXIT(zfsvfs); 1020 return (error); 1021 } 1022 1023 /* 1024 * Attempt to create a new entry in a directory. If the entry 1025 * already exists, truncate the file if permissible, else return 1026 * an error. Return the vp of the created or trunc'd file. 1027 * 1028 * IN: dvp - vnode of directory to put new file entry in. 1029 * name - name of new file entry. 1030 * vap - attributes of new file. 1031 * excl - flag indicating exclusive or non-exclusive mode. 1032 * mode - mode to open file with. 1033 * cr - credentials of caller. 1034 * flag - large file flag [UNUSED]. 1035 * 1036 * OUT: vpp - vnode of created or trunc'd entry. 1037 * 1038 * RETURN: 0 if success 1039 * error code if failure 1040 * 1041 * Timestamps: 1042 * dvp - ctime|mtime updated if new entry created 1043 * vp - ctime|mtime always, atime if new 1044 */ 1045 /* ARGSUSED */ 1046 static int 1047 zfs_create(vnode_t *dvp, char *name, vattr_t *vap, vcexcl_t excl, 1048 int mode, vnode_t **vpp, cred_t *cr, int flag) 1049 { 1050 znode_t *zp, *dzp = VTOZ(dvp); 1051 zfsvfs_t *zfsvfs = dzp->z_zfsvfs; 1052 zilog_t *zilog; 1053 objset_t *os; 1054 zfs_dirlock_t *dl; 1055 dmu_tx_t *tx; 1056 int error; 1057 uint64_t zoid; 1058 1059 ZFS_ENTER_VERIFY_ZP(zfsvfs, dzp); 1060 os = zfsvfs->z_os; 1061 zilog = zfsvfs->z_log; 1062 1063 top: 1064 *vpp = NULL; 1065 1066 if ((vap->va_mode & VSVTX) && secpolicy_vnode_stky_modify(cr)) 1067 vap->va_mode &= ~VSVTX; 1068 1069 if (*name == '\0') { 1070 /* 1071 * Null component name refers to the directory itself. 1072 */ 1073 VN_HOLD(dvp); 1074 zp = dzp; 1075 dl = NULL; 1076 error = 0; 1077 } else { 1078 /* possible VN_HOLD(zp) */ 1079 if (error = zfs_dirent_lock(&dl, dzp, name, &zp, 0)) { 1080 if (strcmp(name, "..") == 0) 1081 error = EISDIR; 1082 ZFS_EXIT(zfsvfs); 1083 return (error); 1084 } 1085 } 1086 1087 zoid = zp ? zp->z_id : -1ULL; 1088 1089 if (zp == NULL) { 1090 /* 1091 * Create a new file object and update the directory 1092 * to reference it. 1093 */ 1094 if (error = zfs_zaccess(dzp, ACE_ADD_FILE, cr)) { 1095 goto out; 1096 } 1097 1098 /* 1099 * We only support the creation of regular files in 1100 * extended attribute directories. 1101 */ 1102 if ((dzp->z_phys->zp_flags & ZFS_XATTR) && 1103 (vap->va_type != VREG)) { 1104 error = EINVAL; 1105 goto out; 1106 } 1107 1108 tx = dmu_tx_create(os); 1109 dmu_tx_hold_bonus(tx, DMU_NEW_OBJECT); 1110 dmu_tx_hold_bonus(tx, dzp->z_id); 1111 dmu_tx_hold_zap(tx, dzp->z_id, TRUE, name); 1112 if (dzp->z_phys->zp_flags & ZFS_INHERIT_ACE) 1113 dmu_tx_hold_write(tx, DMU_NEW_OBJECT, 1114 0, SPA_MAXBLOCKSIZE); 1115 error = dmu_tx_assign(tx, zfsvfs->z_assign); 1116 if (error) { 1117 zfs_dirent_unlock(dl); 1118 if (error == ERESTART && 1119 zfsvfs->z_assign == TXG_NOWAIT) { 1120 dmu_tx_wait(tx); 1121 dmu_tx_abort(tx); 1122 goto top; 1123 } 1124 dmu_tx_abort(tx); 1125 ZFS_EXIT(zfsvfs); 1126 return (error); 1127 } 1128 zfs_mknode(dzp, vap, &zoid, tx, cr, 0, &zp, 0); 1129 ASSERT(zp->z_id == zoid); 1130 (void) zfs_link_create(dl, zp, tx, ZNEW); 1131 zfs_log_create(zilog, tx, TX_CREATE, dzp, zp, name); 1132 dmu_tx_commit(tx); 1133 } else { 1134 /* 1135 * A directory entry already exists for this name. 1136 */ 1137 /* 1138 * Can't truncate an existing file if in exclusive mode. 1139 */ 1140 if (excl == EXCL) { 1141 error = EEXIST; 1142 goto out; 1143 } 1144 /* 1145 * Can't open a directory for writing. 1146 */ 1147 if ((ZTOV(zp)->v_type == VDIR) && (mode & S_IWRITE)) { 1148 error = EISDIR; 1149 goto out; 1150 } 1151 /* 1152 * Verify requested access to file. 1153 */ 1154 if (mode && (error = zfs_zaccess_rwx(zp, mode, cr))) { 1155 goto out; 1156 } 1157 1158 mutex_enter(&dzp->z_lock); 1159 dzp->z_seq++; 1160 mutex_exit(&dzp->z_lock); 1161 1162 /* 1163 * Truncate regular files if requested. 1164 */ 1165 if ((ZTOV(zp)->v_type == VREG) && 1166 (vap->va_mask & AT_SIZE) && (vap->va_size == 0)) { 1167 error = zfs_freesp(zp, 0, 0, mode, TRUE); 1168 if (error == ERESTART && 1169 zfsvfs->z_assign == TXG_NOWAIT) { 1170 /* NB: we already did dmu_tx_wait() */ 1171 zfs_dirent_unlock(dl); 1172 VN_RELE(ZTOV(zp)); 1173 goto top; 1174 } 1175 1176 if (error == 0) { 1177 vnevent_create(ZTOV(zp)); 1178 } 1179 } 1180 } 1181 out: 1182 1183 if (dl) 1184 zfs_dirent_unlock(dl); 1185 1186 if (error) { 1187 if (zp) 1188 VN_RELE(ZTOV(zp)); 1189 } else { 1190 *vpp = ZTOV(zp); 1191 /* 1192 * If vnode is for a device return a specfs vnode instead. 1193 */ 1194 if (IS_DEVVP(*vpp)) { 1195 struct vnode *svp; 1196 1197 svp = specvp(*vpp, (*vpp)->v_rdev, (*vpp)->v_type, cr); 1198 VN_RELE(*vpp); 1199 if (svp == NULL) { 1200 error = ENOSYS; 1201 } 1202 *vpp = svp; 1203 } 1204 } 1205 1206 ZFS_EXIT(zfsvfs); 1207 return (error); 1208 } 1209 1210 /* 1211 * Remove an entry from a directory. 1212 * 1213 * IN: dvp - vnode of directory to remove entry from. 1214 * name - name of entry to remove. 1215 * cr - credentials of caller. 1216 * 1217 * RETURN: 0 if success 1218 * error code if failure 1219 * 1220 * Timestamps: 1221 * dvp - ctime|mtime 1222 * vp - ctime (if nlink > 0) 1223 */ 1224 static int 1225 zfs_remove(vnode_t *dvp, char *name, cred_t *cr) 1226 { 1227 znode_t *zp, *dzp = VTOZ(dvp); 1228 znode_t *xzp = NULL; 1229 vnode_t *vp; 1230 zfsvfs_t *zfsvfs = dzp->z_zfsvfs; 1231 zilog_t *zilog; 1232 uint64_t acl_obj, xattr_obj; 1233 zfs_dirlock_t *dl; 1234 dmu_tx_t *tx; 1235 boolean_t may_delete_now, delete_now = FALSE; 1236 boolean_t unlinked; 1237 int error; 1238 1239 ZFS_ENTER_VERIFY_ZP(zfsvfs, dzp); 1240 zilog = zfsvfs->z_log; 1241 1242 top: 1243 /* 1244 * Attempt to lock directory; fail if entry doesn't exist. 1245 */ 1246 if (error = zfs_dirent_lock(&dl, dzp, name, &zp, ZEXISTS)) { 1247 ZFS_EXIT(zfsvfs); 1248 return (error); 1249 } 1250 1251 vp = ZTOV(zp); 1252 1253 if (error = zfs_zaccess_delete(dzp, zp, cr)) { 1254 goto out; 1255 } 1256 1257 /* 1258 * Need to use rmdir for removing directories. 1259 */ 1260 if (vp->v_type == VDIR) { 1261 error = EPERM; 1262 goto out; 1263 } 1264 1265 vnevent_remove(vp, dvp, name); 1266 1267 dnlc_remove(dvp, name); 1268 1269 mutex_enter(&vp->v_lock); 1270 may_delete_now = vp->v_count == 1 && !vn_has_cached_data(vp); 1271 mutex_exit(&vp->v_lock); 1272 1273 /* 1274 * We may delete the znode now, or we may put it in the unlinked set; 1275 * it depends on whether we're the last link, and on whether there are 1276 * other holds on the vnode. So we dmu_tx_hold() the right things to 1277 * allow for either case. 1278 */ 1279 tx = dmu_tx_create(zfsvfs->z_os); 1280 dmu_tx_hold_zap(tx, dzp->z_id, FALSE, name); 1281 dmu_tx_hold_bonus(tx, zp->z_id); 1282 if (may_delete_now) 1283 dmu_tx_hold_free(tx, zp->z_id, 0, DMU_OBJECT_END); 1284 1285 /* are there any extended attributes? */ 1286 if ((xattr_obj = zp->z_phys->zp_xattr) != 0) { 1287 /* XXX - do we need this if we are deleting? */ 1288 dmu_tx_hold_bonus(tx, xattr_obj); 1289 } 1290 1291 /* are there any additional acls */ 1292 if ((acl_obj = zp->z_phys->zp_acl.z_acl_extern_obj) != 0 && 1293 may_delete_now) 1294 dmu_tx_hold_free(tx, acl_obj, 0, DMU_OBJECT_END); 1295 1296 /* charge as an update -- would be nice not to charge at all */ 1297 dmu_tx_hold_zap(tx, zfsvfs->z_unlinkedobj, FALSE, NULL); 1298 1299 error = dmu_tx_assign(tx, zfsvfs->z_assign); 1300 if (error) { 1301 zfs_dirent_unlock(dl); 1302 VN_RELE(vp); 1303 if (error == ERESTART && zfsvfs->z_assign == TXG_NOWAIT) { 1304 dmu_tx_wait(tx); 1305 dmu_tx_abort(tx); 1306 goto top; 1307 } 1308 dmu_tx_abort(tx); 1309 ZFS_EXIT(zfsvfs); 1310 return (error); 1311 } 1312 1313 /* 1314 * Remove the directory entry. 1315 */ 1316 error = zfs_link_destroy(dl, zp, tx, 0, &unlinked); 1317 1318 if (error) { 1319 dmu_tx_commit(tx); 1320 goto out; 1321 } 1322 1323 if (unlinked) { 1324 mutex_enter(&vp->v_lock); 1325 delete_now = may_delete_now && 1326 vp->v_count == 1 && !vn_has_cached_data(vp) && 1327 zp->z_phys->zp_xattr == xattr_obj && 1328 zp->z_phys->zp_acl.z_acl_extern_obj == acl_obj; 1329 mutex_exit(&vp->v_lock); 1330 } 1331 1332 if (delete_now) { 1333 if (zp->z_phys->zp_xattr) { 1334 error = zfs_zget(zfsvfs, zp->z_phys->zp_xattr, &xzp); 1335 ASSERT3U(error, ==, 0); 1336 ASSERT3U(xzp->z_phys->zp_links, ==, 2); 1337 dmu_buf_will_dirty(xzp->z_dbuf, tx); 1338 mutex_enter(&xzp->z_lock); 1339 xzp->z_unlinked = 1; 1340 xzp->z_phys->zp_links = 0; 1341 mutex_exit(&xzp->z_lock); 1342 zfs_unlinked_add(xzp, tx); 1343 zp->z_phys->zp_xattr = 0; /* probably unnecessary */ 1344 } 1345 mutex_enter(&zp->z_lock); 1346 mutex_enter(&vp->v_lock); 1347 vp->v_count--; 1348 ASSERT3U(vp->v_count, ==, 0); 1349 mutex_exit(&vp->v_lock); 1350 mutex_exit(&zp->z_lock); 1351 zfs_znode_delete(zp, tx); 1352 VFS_RELE(zfsvfs->z_vfs); 1353 } else if (unlinked) { 1354 zfs_unlinked_add(zp, tx); 1355 } 1356 1357 zfs_log_remove(zilog, tx, TX_REMOVE, dzp, name); 1358 1359 dmu_tx_commit(tx); 1360 out: 1361 zfs_dirent_unlock(dl); 1362 1363 if (!delete_now) { 1364 VN_RELE(vp); 1365 } else if (xzp) { 1366 /* this rele delayed to prevent nesting transactions */ 1367 VN_RELE(ZTOV(xzp)); 1368 } 1369 1370 ZFS_EXIT(zfsvfs); 1371 return (error); 1372 } 1373 1374 /* 1375 * Create a new directory and insert it into dvp using the name 1376 * provided. Return a pointer to the inserted directory. 1377 * 1378 * IN: dvp - vnode of directory to add subdir to. 1379 * dirname - name of new directory. 1380 * vap - attributes of new directory. 1381 * cr - credentials of caller. 1382 * 1383 * OUT: vpp - vnode of created directory. 1384 * 1385 * RETURN: 0 if success 1386 * error code if failure 1387 * 1388 * Timestamps: 1389 * dvp - ctime|mtime updated 1390 * vp - ctime|mtime|atime updated 1391 */ 1392 static int 1393 zfs_mkdir(vnode_t *dvp, char *dirname, vattr_t *vap, vnode_t **vpp, cred_t *cr) 1394 { 1395 znode_t *zp, *dzp = VTOZ(dvp); 1396 zfsvfs_t *zfsvfs = dzp->z_zfsvfs; 1397 zilog_t *zilog; 1398 zfs_dirlock_t *dl; 1399 uint64_t zoid = 0; 1400 dmu_tx_t *tx; 1401 int error; 1402 1403 ASSERT(vap->va_type == VDIR); 1404 1405 ZFS_ENTER_VERIFY_ZP(zfsvfs, dzp); 1406 zilog = zfsvfs->z_log; 1407 1408 if (dzp->z_phys->zp_flags & ZFS_XATTR) { 1409 ZFS_EXIT(zfsvfs); 1410 return (EINVAL); 1411 } 1412 top: 1413 *vpp = NULL; 1414 1415 /* 1416 * First make sure the new directory doesn't exist. 1417 */ 1418 if (error = zfs_dirent_lock(&dl, dzp, dirname, &zp, ZNEW)) { 1419 ZFS_EXIT(zfsvfs); 1420 return (error); 1421 } 1422 1423 if (error = zfs_zaccess(dzp, ACE_ADD_SUBDIRECTORY, cr)) { 1424 zfs_dirent_unlock(dl); 1425 ZFS_EXIT(zfsvfs); 1426 return (error); 1427 } 1428 1429 /* 1430 * Add a new entry to the directory. 1431 */ 1432 tx = dmu_tx_create(zfsvfs->z_os); 1433 dmu_tx_hold_zap(tx, dzp->z_id, TRUE, dirname); 1434 dmu_tx_hold_zap(tx, DMU_NEW_OBJECT, FALSE, NULL); 1435 if (dzp->z_phys->zp_flags & ZFS_INHERIT_ACE) 1436 dmu_tx_hold_write(tx, DMU_NEW_OBJECT, 1437 0, SPA_MAXBLOCKSIZE); 1438 error = dmu_tx_assign(tx, zfsvfs->z_assign); 1439 if (error) { 1440 zfs_dirent_unlock(dl); 1441 if (error == ERESTART && zfsvfs->z_assign == TXG_NOWAIT) { 1442 dmu_tx_wait(tx); 1443 dmu_tx_abort(tx); 1444 goto top; 1445 } 1446 dmu_tx_abort(tx); 1447 ZFS_EXIT(zfsvfs); 1448 return (error); 1449 } 1450 1451 /* 1452 * Create new node. 1453 */ 1454 zfs_mknode(dzp, vap, &zoid, tx, cr, 0, &zp, 0); 1455 1456 /* 1457 * Now put new name in parent dir. 1458 */ 1459 (void) zfs_link_create(dl, zp, tx, ZNEW); 1460 1461 *vpp = ZTOV(zp); 1462 1463 zfs_log_create(zilog, tx, TX_MKDIR, dzp, zp, dirname); 1464 dmu_tx_commit(tx); 1465 1466 zfs_dirent_unlock(dl); 1467 1468 ZFS_EXIT(zfsvfs); 1469 return (0); 1470 } 1471 1472 /* 1473 * Remove a directory subdir entry. If the current working 1474 * directory is the same as the subdir to be removed, the 1475 * remove will fail. 1476 * 1477 * IN: dvp - vnode of directory to remove from. 1478 * name - name of directory to be removed. 1479 * cwd - vnode of current working directory. 1480 * cr - credentials of caller. 1481 * 1482 * RETURN: 0 if success 1483 * error code if failure 1484 * 1485 * Timestamps: 1486 * dvp - ctime|mtime updated 1487 */ 1488 static int 1489 zfs_rmdir(vnode_t *dvp, char *name, vnode_t *cwd, cred_t *cr) 1490 { 1491 znode_t *dzp = VTOZ(dvp); 1492 znode_t *zp; 1493 vnode_t *vp; 1494 zfsvfs_t *zfsvfs = dzp->z_zfsvfs; 1495 zilog_t *zilog; 1496 zfs_dirlock_t *dl; 1497 dmu_tx_t *tx; 1498 int error; 1499 1500 ZFS_ENTER_VERIFY_ZP(zfsvfs, dzp); 1501 zilog = zfsvfs->z_log; 1502 1503 top: 1504 zp = NULL; 1505 1506 /* 1507 * Attempt to lock directory; fail if entry doesn't exist. 1508 */ 1509 if (error = zfs_dirent_lock(&dl, dzp, name, &zp, ZEXISTS)) { 1510 ZFS_EXIT(zfsvfs); 1511 return (error); 1512 } 1513 1514 vp = ZTOV(zp); 1515 1516 if (error = zfs_zaccess_delete(dzp, zp, cr)) { 1517 goto out; 1518 } 1519 1520 if (vp->v_type != VDIR) { 1521 error = ENOTDIR; 1522 goto out; 1523 } 1524 1525 if (vp == cwd) { 1526 error = EINVAL; 1527 goto out; 1528 } 1529 1530 vnevent_rmdir(vp, dvp, name); 1531 1532 /* 1533 * Grab a lock on the directory to make sure that noone is 1534 * trying to add (or lookup) entries while we are removing it. 1535 */ 1536 rw_enter(&zp->z_name_lock, RW_WRITER); 1537 1538 /* 1539 * Grab a lock on the parent pointer to make sure we play well 1540 * with the treewalk and directory rename code. 1541 */ 1542 rw_enter(&zp->z_parent_lock, RW_WRITER); 1543 1544 tx = dmu_tx_create(zfsvfs->z_os); 1545 dmu_tx_hold_zap(tx, dzp->z_id, FALSE, name); 1546 dmu_tx_hold_bonus(tx, zp->z_id); 1547 dmu_tx_hold_zap(tx, zfsvfs->z_unlinkedobj, FALSE, NULL); 1548 error = dmu_tx_assign(tx, zfsvfs->z_assign); 1549 if (error) { 1550 rw_exit(&zp->z_parent_lock); 1551 rw_exit(&zp->z_name_lock); 1552 zfs_dirent_unlock(dl); 1553 VN_RELE(vp); 1554 if (error == ERESTART && zfsvfs->z_assign == TXG_NOWAIT) { 1555 dmu_tx_wait(tx); 1556 dmu_tx_abort(tx); 1557 goto top; 1558 } 1559 dmu_tx_abort(tx); 1560 ZFS_EXIT(zfsvfs); 1561 return (error); 1562 } 1563 1564 error = zfs_link_destroy(dl, zp, tx, 0, NULL); 1565 1566 if (error == 0) 1567 zfs_log_remove(zilog, tx, TX_RMDIR, dzp, name); 1568 1569 dmu_tx_commit(tx); 1570 1571 rw_exit(&zp->z_parent_lock); 1572 rw_exit(&zp->z_name_lock); 1573 out: 1574 zfs_dirent_unlock(dl); 1575 1576 VN_RELE(vp); 1577 1578 ZFS_EXIT(zfsvfs); 1579 return (error); 1580 } 1581 1582 /* 1583 * Read as many directory entries as will fit into the provided 1584 * buffer from the given directory cursor position (specified in 1585 * the uio structure. 1586 * 1587 * IN: vp - vnode of directory to read. 1588 * uio - structure supplying read location, range info, 1589 * and return buffer. 1590 * cr - credentials of caller. 1591 * 1592 * OUT: uio - updated offset and range, buffer filled. 1593 * eofp - set to true if end-of-file detected. 1594 * 1595 * RETURN: 0 if success 1596 * error code if failure 1597 * 1598 * Timestamps: 1599 * vp - atime updated 1600 * 1601 * Note that the low 4 bits of the cookie returned by zap is always zero. 1602 * This allows us to use the low range for "special" directory entries: 1603 * We use 0 for '.', and 1 for '..'. If this is the root of the filesystem, 1604 * we use the offset 2 for the '.zfs' directory. 1605 */ 1606 /* ARGSUSED */ 1607 static int 1608 zfs_readdir(vnode_t *vp, uio_t *uio, cred_t *cr, int *eofp) 1609 { 1610 znode_t *zp = VTOZ(vp); 1611 iovec_t *iovp; 1612 dirent64_t *odp; 1613 zfsvfs_t *zfsvfs = zp->z_zfsvfs; 1614 objset_t *os; 1615 caddr_t outbuf; 1616 size_t bufsize; 1617 zap_cursor_t zc; 1618 zap_attribute_t zap; 1619 uint_t bytes_wanted; 1620 uint64_t offset; /* must be unsigned; checks for < 1 */ 1621 int local_eof; 1622 int outcount; 1623 int error; 1624 uint8_t prefetch; 1625 1626 ZFS_ENTER_VERIFY_ZP(zfsvfs, zp); 1627 1628 /* 1629 * If we are not given an eof variable, 1630 * use a local one. 1631 */ 1632 if (eofp == NULL) 1633 eofp = &local_eof; 1634 1635 /* 1636 * Check for valid iov_len. 1637 */ 1638 if (uio->uio_iov->iov_len <= 0) { 1639 ZFS_EXIT(zfsvfs); 1640 return (EINVAL); 1641 } 1642 1643 /* 1644 * Quit if directory has been removed (posix) 1645 */ 1646 if ((*eofp = zp->z_unlinked) != 0) { 1647 ZFS_EXIT(zfsvfs); 1648 return (0); 1649 } 1650 1651 error = 0; 1652 os = zfsvfs->z_os; 1653 offset = uio->uio_loffset; 1654 prefetch = zp->z_zn_prefetch; 1655 1656 /* 1657 * Initialize the iterator cursor. 1658 */ 1659 if (offset <= 3) { 1660 /* 1661 * Start iteration from the beginning of the directory. 1662 */ 1663 zap_cursor_init(&zc, os, zp->z_id); 1664 } else { 1665 /* 1666 * The offset is a serialized cursor. 1667 */ 1668 zap_cursor_init_serialized(&zc, os, zp->z_id, offset); 1669 } 1670 1671 /* 1672 * Get space to change directory entries into fs independent format. 1673 */ 1674 iovp = uio->uio_iov; 1675 bytes_wanted = iovp->iov_len; 1676 if (uio->uio_segflg != UIO_SYSSPACE || uio->uio_iovcnt != 1) { 1677 bufsize = bytes_wanted; 1678 outbuf = kmem_alloc(bufsize, KM_SLEEP); 1679 odp = (struct dirent64 *)outbuf; 1680 } else { 1681 bufsize = bytes_wanted; 1682 odp = (struct dirent64 *)iovp->iov_base; 1683 } 1684 1685 /* 1686 * Transform to file-system independent format 1687 */ 1688 outcount = 0; 1689 while (outcount < bytes_wanted) { 1690 ino64_t objnum; 1691 ushort_t reclen; 1692 off64_t *next; 1693 1694 /* 1695 * Special case `.', `..', and `.zfs'. 1696 */ 1697 if (offset == 0) { 1698 (void) strcpy(zap.za_name, "."); 1699 objnum = zp->z_id; 1700 } else if (offset == 1) { 1701 (void) strcpy(zap.za_name, ".."); 1702 objnum = zp->z_phys->zp_parent; 1703 } else if (offset == 2 && zfs_show_ctldir(zp)) { 1704 (void) strcpy(zap.za_name, ZFS_CTLDIR_NAME); 1705 objnum = ZFSCTL_INO_ROOT; 1706 } else { 1707 /* 1708 * Grab next entry. 1709 */ 1710 if (error = zap_cursor_retrieve(&zc, &zap)) { 1711 if ((*eofp = (error == ENOENT)) != 0) 1712 break; 1713 else 1714 goto update; 1715 } 1716 1717 if (zap.za_integer_length != 8 || 1718 zap.za_num_integers != 1) { 1719 cmn_err(CE_WARN, "zap_readdir: bad directory " 1720 "entry, obj = %lld, offset = %lld\n", 1721 (u_longlong_t)zp->z_id, 1722 (u_longlong_t)offset); 1723 error = ENXIO; 1724 goto update; 1725 } 1726 1727 objnum = ZFS_DIRENT_OBJ(zap.za_first_integer); 1728 /* 1729 * MacOS X can extract the object type here such as: 1730 * uint8_t type = ZFS_DIRENT_TYPE(zap.za_first_integer); 1731 */ 1732 } 1733 reclen = DIRENT64_RECLEN(strlen(zap.za_name)); 1734 1735 /* 1736 * Will this entry fit in the buffer? 1737 */ 1738 if (outcount + reclen > bufsize) { 1739 /* 1740 * Did we manage to fit anything in the buffer? 1741 */ 1742 if (!outcount) { 1743 error = EINVAL; 1744 goto update; 1745 } 1746 break; 1747 } 1748 /* 1749 * Add this entry: 1750 */ 1751 odp->d_ino = objnum; 1752 odp->d_reclen = reclen; 1753 /* NOTE: d_off is the offset for the *next* entry */ 1754 next = &(odp->d_off); 1755 (void) strncpy(odp->d_name, zap.za_name, 1756 DIRENT64_NAMELEN(reclen)); 1757 outcount += reclen; 1758 odp = (dirent64_t *)((intptr_t)odp + reclen); 1759 1760 ASSERT(outcount <= bufsize); 1761 1762 /* Prefetch znode */ 1763 if (prefetch) 1764 dmu_prefetch(os, objnum, 0, 0); 1765 1766 /* 1767 * Move to the next entry, fill in the previous offset. 1768 */ 1769 if (offset > 2 || (offset == 2 && !zfs_show_ctldir(zp))) { 1770 zap_cursor_advance(&zc); 1771 offset = zap_cursor_serialize(&zc); 1772 } else { 1773 offset += 1; 1774 } 1775 *next = offset; 1776 } 1777 zp->z_zn_prefetch = B_FALSE; /* a lookup will re-enable pre-fetching */ 1778 1779 if (uio->uio_segflg == UIO_SYSSPACE && uio->uio_iovcnt == 1) { 1780 iovp->iov_base += outcount; 1781 iovp->iov_len -= outcount; 1782 uio->uio_resid -= outcount; 1783 } else if (error = uiomove(outbuf, (long)outcount, UIO_READ, uio)) { 1784 /* 1785 * Reset the pointer. 1786 */ 1787 offset = uio->uio_loffset; 1788 } 1789 1790 update: 1791 zap_cursor_fini(&zc); 1792 if (uio->uio_segflg != UIO_SYSSPACE || uio->uio_iovcnt != 1) 1793 kmem_free(outbuf, bufsize); 1794 1795 if (error == ENOENT) 1796 error = 0; 1797 1798 ZFS_ACCESSTIME_STAMP(zfsvfs, zp); 1799 1800 uio->uio_loffset = offset; 1801 ZFS_EXIT(zfsvfs); 1802 return (error); 1803 } 1804 1805 ulong_t zfs_fsync_sync_cnt = 4; 1806 1807 static int 1808 zfs_fsync(vnode_t *vp, int syncflag, cred_t *cr) 1809 { 1810 znode_t *zp = VTOZ(vp); 1811 zfsvfs_t *zfsvfs = zp->z_zfsvfs; 1812 1813 /* 1814 * Regardless of whether this is required for standards conformance, 1815 * this is the logical behavior when fsync() is called on a file with 1816 * dirty pages. We use B_ASYNC since the ZIL transactions are already 1817 * going to be pushed out as part of the zil_commit(). 1818 */ 1819 if (vn_has_cached_data(vp) && !(syncflag & FNODSYNC) && 1820 (vp->v_type == VREG) && !(IS_SWAPVP(vp))) 1821 (void) VOP_PUTPAGE(vp, (offset_t)0, (size_t)0, B_ASYNC, cr); 1822 1823 (void) tsd_set(zfs_fsyncer_key, (void *)zfs_fsync_sync_cnt); 1824 1825 ZFS_ENTER_VERIFY_ZP(zfsvfs, zp); 1826 zil_commit(zfsvfs->z_log, zp->z_last_itx, zp->z_id); 1827 ZFS_EXIT(zfsvfs); 1828 return (0); 1829 } 1830 1831 /* 1832 * Get the requested file attributes and place them in the provided 1833 * vattr structure. 1834 * 1835 * IN: vp - vnode of file. 1836 * vap - va_mask identifies requested attributes. 1837 * flags - [UNUSED] 1838 * cr - credentials of caller. 1839 * 1840 * OUT: vap - attribute values. 1841 * 1842 * RETURN: 0 (always succeeds) 1843 */ 1844 /* ARGSUSED */ 1845 static int 1846 zfs_getattr(vnode_t *vp, vattr_t *vap, int flags, cred_t *cr) 1847 { 1848 znode_t *zp = VTOZ(vp); 1849 zfsvfs_t *zfsvfs = zp->z_zfsvfs; 1850 znode_phys_t *pzp; 1851 int error; 1852 uint64_t links; 1853 1854 ZFS_ENTER_VERIFY_ZP(zfsvfs, zp); 1855 pzp = zp->z_phys; 1856 1857 /* 1858 * Return all attributes. It's cheaper to provide the answer 1859 * than to determine whether we were asked the question. 1860 */ 1861 mutex_enter(&zp->z_lock); 1862 1863 vap->va_type = vp->v_type; 1864 vap->va_mode = pzp->zp_mode & MODEMASK; 1865 vap->va_uid = zp->z_phys->zp_uid; 1866 vap->va_gid = zp->z_phys->zp_gid; 1867 vap->va_fsid = zp->z_zfsvfs->z_vfs->vfs_dev; 1868 vap->va_nodeid = zp->z_id; 1869 if ((vp->v_flag & VROOT) && zfs_show_ctldir(zp)) 1870 links = pzp->zp_links + 1; 1871 else 1872 links = pzp->zp_links; 1873 vap->va_nlink = MIN(links, UINT32_MAX); /* nlink_t limit! */ 1874 vap->va_size = pzp->zp_size; 1875 vap->va_rdev = vp->v_rdev; 1876 vap->va_seq = zp->z_seq; 1877 1878 ZFS_TIME_DECODE(&vap->va_atime, pzp->zp_atime); 1879 ZFS_TIME_DECODE(&vap->va_mtime, pzp->zp_mtime); 1880 ZFS_TIME_DECODE(&vap->va_ctime, pzp->zp_ctime); 1881 1882 /* 1883 * If ACL is trivial don't bother looking for ACE_READ_ATTRIBUTES. 1884 * Also, if we are the owner don't bother, since owner should 1885 * always be allowed to read basic attributes of file. 1886 */ 1887 if (!(zp->z_phys->zp_flags & ZFS_ACL_TRIVIAL) && 1888 (zp->z_phys->zp_uid != crgetuid(cr))) { 1889 if (error = zfs_zaccess(zp, ACE_READ_ATTRIBUTES, cr)) { 1890 mutex_exit(&zp->z_lock); 1891 ZFS_EXIT(zfsvfs); 1892 return (error); 1893 } 1894 } 1895 1896 mutex_exit(&zp->z_lock); 1897 1898 dmu_object_size_from_db(zp->z_dbuf, &vap->va_blksize, &vap->va_nblocks); 1899 1900 if (zp->z_blksz == 0) { 1901 /* 1902 * Block size hasn't been set; suggest maximal I/O transfers. 1903 */ 1904 vap->va_blksize = zfsvfs->z_max_blksz; 1905 } 1906 1907 ZFS_EXIT(zfsvfs); 1908 return (0); 1909 } 1910 1911 /* 1912 * Set the file attributes to the values contained in the 1913 * vattr structure. 1914 * 1915 * IN: vp - vnode of file to be modified. 1916 * vap - new attribute values. 1917 * flags - ATTR_UTIME set if non-default time values provided. 1918 * cr - credentials of caller. 1919 * 1920 * RETURN: 0 if success 1921 * error code if failure 1922 * 1923 * Timestamps: 1924 * vp - ctime updated, mtime updated if size changed. 1925 */ 1926 /* ARGSUSED */ 1927 static int 1928 zfs_setattr(vnode_t *vp, vattr_t *vap, int flags, cred_t *cr, 1929 caller_context_t *ct) 1930 { 1931 znode_t *zp = VTOZ(vp); 1932 znode_phys_t *pzp; 1933 zfsvfs_t *zfsvfs = zp->z_zfsvfs; 1934 zilog_t *zilog; 1935 dmu_tx_t *tx; 1936 vattr_t oldva; 1937 uint_t mask = vap->va_mask; 1938 uint_t saved_mask; 1939 int trim_mask = 0; 1940 uint64_t new_mode; 1941 znode_t *attrzp; 1942 int need_policy = FALSE; 1943 int err; 1944 1945 if (mask == 0) 1946 return (0); 1947 1948 if (mask & AT_NOSET) 1949 return (EINVAL); 1950 1951 if (mask & AT_SIZE && vp->v_type == VDIR) 1952 return (EISDIR); 1953 1954 if (mask & AT_SIZE && vp->v_type != VREG && vp->v_type != VFIFO) 1955 return (EINVAL); 1956 1957 ZFS_ENTER_VERIFY_ZP(zfsvfs, zp); 1958 pzp = zp->z_phys; 1959 zilog = zfsvfs->z_log; 1960 1961 top: 1962 attrzp = NULL; 1963 1964 if (zfsvfs->z_vfs->vfs_flag & VFS_RDONLY) { 1965 ZFS_EXIT(zfsvfs); 1966 return (EROFS); 1967 } 1968 1969 /* 1970 * First validate permissions 1971 */ 1972 1973 if (mask & AT_SIZE) { 1974 err = zfs_zaccess(zp, ACE_WRITE_DATA, cr); 1975 if (err) { 1976 ZFS_EXIT(zfsvfs); 1977 return (err); 1978 } 1979 /* 1980 * XXX - Note, we are not providing any open 1981 * mode flags here (like FNDELAY), so we may 1982 * block if there are locks present... this 1983 * should be addressed in openat(). 1984 */ 1985 do { 1986 err = zfs_freesp(zp, vap->va_size, 0, 0, FALSE); 1987 /* NB: we already did dmu_tx_wait() if necessary */ 1988 } while (err == ERESTART && zfsvfs->z_assign == TXG_NOWAIT); 1989 if (err) { 1990 ZFS_EXIT(zfsvfs); 1991 return (err); 1992 } 1993 } 1994 1995 if (mask & (AT_ATIME|AT_MTIME)) 1996 need_policy = zfs_zaccess_v4_perm(zp, ACE_WRITE_ATTRIBUTES, cr); 1997 1998 if (mask & (AT_UID|AT_GID)) { 1999 int idmask = (mask & (AT_UID|AT_GID)); 2000 int take_owner; 2001 int take_group; 2002 2003 /* 2004 * NOTE: even if a new mode is being set, 2005 * we may clear S_ISUID/S_ISGID bits. 2006 */ 2007 2008 if (!(mask & AT_MODE)) 2009 vap->va_mode = pzp->zp_mode; 2010 2011 /* 2012 * Take ownership or chgrp to group we are a member of 2013 */ 2014 2015 take_owner = (mask & AT_UID) && (vap->va_uid == crgetuid(cr)); 2016 take_group = (mask & AT_GID) && groupmember(vap->va_gid, cr); 2017 2018 /* 2019 * If both AT_UID and AT_GID are set then take_owner and 2020 * take_group must both be set in order to allow taking 2021 * ownership. 2022 * 2023 * Otherwise, send the check through secpolicy_vnode_setattr() 2024 * 2025 */ 2026 2027 if (((idmask == (AT_UID|AT_GID)) && take_owner && take_group) || 2028 ((idmask == AT_UID) && take_owner) || 2029 ((idmask == AT_GID) && take_group)) { 2030 if (zfs_zaccess_v4_perm(zp, ACE_WRITE_OWNER, cr) == 0) { 2031 /* 2032 * Remove setuid/setgid for non-privileged users 2033 */ 2034 secpolicy_setid_clear(vap, cr); 2035 trim_mask = (mask & (AT_UID|AT_GID)); 2036 } else { 2037 need_policy = TRUE; 2038 } 2039 } else { 2040 need_policy = TRUE; 2041 } 2042 } 2043 2044 mutex_enter(&zp->z_lock); 2045 oldva.va_mode = pzp->zp_mode; 2046 oldva.va_uid = zp->z_phys->zp_uid; 2047 oldva.va_gid = zp->z_phys->zp_gid; 2048 mutex_exit(&zp->z_lock); 2049 2050 if (mask & AT_MODE) { 2051 if (zfs_zaccess_v4_perm(zp, ACE_WRITE_ACL, cr) == 0) { 2052 err = secpolicy_setid_setsticky_clear(vp, vap, 2053 &oldva, cr); 2054 if (err) { 2055 ZFS_EXIT(zfsvfs); 2056 return (err); 2057 } 2058 trim_mask |= AT_MODE; 2059 } else { 2060 need_policy = TRUE; 2061 } 2062 } 2063 2064 if (need_policy) { 2065 /* 2066 * If trim_mask is set then take ownership 2067 * has been granted or write_acl is present and user 2068 * has the ability to modify mode. In that case remove 2069 * UID|GID and or MODE from mask so that 2070 * secpolicy_vnode_setattr() doesn't revoke it. 2071 */ 2072 2073 if (trim_mask) { 2074 saved_mask = vap->va_mask; 2075 vap->va_mask &= ~trim_mask; 2076 2077 } 2078 err = secpolicy_vnode_setattr(cr, vp, vap, &oldva, flags, 2079 (int (*)(void *, int, cred_t *))zfs_zaccess_rwx, zp); 2080 if (err) { 2081 ZFS_EXIT(zfsvfs); 2082 return (err); 2083 } 2084 2085 if (trim_mask) 2086 vap->va_mask |= saved_mask; 2087 } 2088 2089 /* 2090 * secpolicy_vnode_setattr, or take ownership may have 2091 * changed va_mask 2092 */ 2093 mask = vap->va_mask; 2094 2095 tx = dmu_tx_create(zfsvfs->z_os); 2096 dmu_tx_hold_bonus(tx, zp->z_id); 2097 2098 if (mask & AT_MODE) { 2099 uint64_t pmode = pzp->zp_mode; 2100 2101 new_mode = (pmode & S_IFMT) | (vap->va_mode & ~S_IFMT); 2102 2103 if (zp->z_phys->zp_acl.z_acl_extern_obj) 2104 dmu_tx_hold_write(tx, 2105 pzp->zp_acl.z_acl_extern_obj, 0, SPA_MAXBLOCKSIZE); 2106 else 2107 dmu_tx_hold_write(tx, DMU_NEW_OBJECT, 2108 0, ZFS_ACL_SIZE(MAX_ACL_SIZE)); 2109 } 2110 2111 if ((mask & (AT_UID | AT_GID)) && zp->z_phys->zp_xattr != 0) { 2112 err = zfs_zget(zp->z_zfsvfs, zp->z_phys->zp_xattr, &attrzp); 2113 if (err) { 2114 dmu_tx_abort(tx); 2115 ZFS_EXIT(zfsvfs); 2116 return (err); 2117 } 2118 dmu_tx_hold_bonus(tx, attrzp->z_id); 2119 } 2120 2121 err = dmu_tx_assign(tx, zfsvfs->z_assign); 2122 if (err) { 2123 if (attrzp) 2124 VN_RELE(ZTOV(attrzp)); 2125 if (err == ERESTART && zfsvfs->z_assign == TXG_NOWAIT) { 2126 dmu_tx_wait(tx); 2127 dmu_tx_abort(tx); 2128 goto top; 2129 } 2130 dmu_tx_abort(tx); 2131 ZFS_EXIT(zfsvfs); 2132 return (err); 2133 } 2134 2135 dmu_buf_will_dirty(zp->z_dbuf, tx); 2136 2137 /* 2138 * Set each attribute requested. 2139 * We group settings according to the locks they need to acquire. 2140 * 2141 * Note: you cannot set ctime directly, although it will be 2142 * updated as a side-effect of calling this function. 2143 */ 2144 2145 mutex_enter(&zp->z_lock); 2146 2147 if (mask & AT_MODE) { 2148 err = zfs_acl_chmod_setattr(zp, new_mode, tx); 2149 ASSERT3U(err, ==, 0); 2150 } 2151 2152 if (attrzp) 2153 mutex_enter(&attrzp->z_lock); 2154 2155 if (mask & AT_UID) { 2156 zp->z_phys->zp_uid = (uint64_t)vap->va_uid; 2157 if (attrzp) { 2158 attrzp->z_phys->zp_uid = (uint64_t)vap->va_uid; 2159 } 2160 } 2161 2162 if (mask & AT_GID) { 2163 zp->z_phys->zp_gid = (uint64_t)vap->va_gid; 2164 if (attrzp) 2165 attrzp->z_phys->zp_gid = (uint64_t)vap->va_gid; 2166 } 2167 2168 if (attrzp) 2169 mutex_exit(&attrzp->z_lock); 2170 2171 if (mask & AT_ATIME) 2172 ZFS_TIME_ENCODE(&vap->va_atime, pzp->zp_atime); 2173 2174 if (mask & AT_MTIME) 2175 ZFS_TIME_ENCODE(&vap->va_mtime, pzp->zp_mtime); 2176 2177 if (mask & AT_SIZE) 2178 zfs_time_stamper_locked(zp, CONTENT_MODIFIED, tx); 2179 else if (mask != 0) 2180 zfs_time_stamper_locked(zp, STATE_CHANGED, tx); 2181 2182 if (mask != 0) 2183 zfs_log_setattr(zilog, tx, TX_SETATTR, zp, vap, mask); 2184 2185 mutex_exit(&zp->z_lock); 2186 2187 if (attrzp) 2188 VN_RELE(ZTOV(attrzp)); 2189 2190 dmu_tx_commit(tx); 2191 2192 ZFS_EXIT(zfsvfs); 2193 return (err); 2194 } 2195 2196 typedef struct zfs_zlock { 2197 krwlock_t *zl_rwlock; /* lock we acquired */ 2198 znode_t *zl_znode; /* znode we held */ 2199 struct zfs_zlock *zl_next; /* next in list */ 2200 } zfs_zlock_t; 2201 2202 /* 2203 * Drop locks and release vnodes that were held by zfs_rename_lock(). 2204 */ 2205 static void 2206 zfs_rename_unlock(zfs_zlock_t **zlpp) 2207 { 2208 zfs_zlock_t *zl; 2209 2210 while ((zl = *zlpp) != NULL) { 2211 if (zl->zl_znode != NULL) 2212 VN_RELE(ZTOV(zl->zl_znode)); 2213 rw_exit(zl->zl_rwlock); 2214 *zlpp = zl->zl_next; 2215 kmem_free(zl, sizeof (*zl)); 2216 } 2217 } 2218 2219 /* 2220 * Search back through the directory tree, using the ".." entries. 2221 * Lock each directory in the chain to prevent concurrent renames. 2222 * Fail any attempt to move a directory into one of its own descendants. 2223 * XXX - z_parent_lock can overlap with map or grow locks 2224 */ 2225 static int 2226 zfs_rename_lock(znode_t *szp, znode_t *tdzp, znode_t *sdzp, zfs_zlock_t **zlpp) 2227 { 2228 zfs_zlock_t *zl; 2229 znode_t *zp = tdzp; 2230 uint64_t rootid = zp->z_zfsvfs->z_root; 2231 uint64_t *oidp = &zp->z_id; 2232 krwlock_t *rwlp = &szp->z_parent_lock; 2233 krw_t rw = RW_WRITER; 2234 2235 /* 2236 * First pass write-locks szp and compares to zp->z_id. 2237 * Later passes read-lock zp and compare to zp->z_parent. 2238 */ 2239 do { 2240 if (!rw_tryenter(rwlp, rw)) { 2241 /* 2242 * Another thread is renaming in this path. 2243 * Note that if we are a WRITER, we don't have any 2244 * parent_locks held yet. 2245 */ 2246 if (rw == RW_READER && zp->z_id > szp->z_id) { 2247 /* 2248 * Drop our locks and restart 2249 */ 2250 zfs_rename_unlock(&zl); 2251 *zlpp = NULL; 2252 zp = tdzp; 2253 oidp = &zp->z_id; 2254 rwlp = &szp->z_parent_lock; 2255 rw = RW_WRITER; 2256 continue; 2257 } else { 2258 /* 2259 * Wait for other thread to drop its locks 2260 */ 2261 rw_enter(rwlp, rw); 2262 } 2263 } 2264 2265 zl = kmem_alloc(sizeof (*zl), KM_SLEEP); 2266 zl->zl_rwlock = rwlp; 2267 zl->zl_znode = NULL; 2268 zl->zl_next = *zlpp; 2269 *zlpp = zl; 2270 2271 if (*oidp == szp->z_id) /* We're a descendant of szp */ 2272 return (EINVAL); 2273 2274 if (*oidp == rootid) /* We've hit the top */ 2275 return (0); 2276 2277 if (rw == RW_READER) { /* i.e. not the first pass */ 2278 int error = zfs_zget(zp->z_zfsvfs, *oidp, &zp); 2279 if (error) 2280 return (error); 2281 zl->zl_znode = zp; 2282 } 2283 oidp = &zp->z_phys->zp_parent; 2284 rwlp = &zp->z_parent_lock; 2285 rw = RW_READER; 2286 2287 } while (zp->z_id != sdzp->z_id); 2288 2289 return (0); 2290 } 2291 2292 /* 2293 * Move an entry from the provided source directory to the target 2294 * directory. Change the entry name as indicated. 2295 * 2296 * IN: sdvp - Source directory containing the "old entry". 2297 * snm - Old entry name. 2298 * tdvp - Target directory to contain the "new entry". 2299 * tnm - New entry name. 2300 * cr - credentials of caller. 2301 * 2302 * RETURN: 0 if success 2303 * error code if failure 2304 * 2305 * Timestamps: 2306 * sdvp,tdvp - ctime|mtime updated 2307 */ 2308 static int 2309 zfs_rename(vnode_t *sdvp, char *snm, vnode_t *tdvp, char *tnm, cred_t *cr) 2310 { 2311 znode_t *tdzp, *szp, *tzp; 2312 znode_t *sdzp = VTOZ(sdvp); 2313 zfsvfs_t *zfsvfs = sdzp->z_zfsvfs; 2314 zilog_t *zilog; 2315 vnode_t *realvp; 2316 zfs_dirlock_t *sdl, *tdl; 2317 dmu_tx_t *tx; 2318 zfs_zlock_t *zl; 2319 int cmp, serr, terr, error; 2320 2321 ZFS_ENTER_VERIFY_ZP(zfsvfs, sdzp); 2322 zilog = zfsvfs->z_log; 2323 2324 /* 2325 * Make sure we have the real vp for the target directory. 2326 */ 2327 if (VOP_REALVP(tdvp, &realvp) == 0) 2328 tdvp = realvp; 2329 2330 if (tdvp->v_vfsp != sdvp->v_vfsp) { 2331 ZFS_EXIT(zfsvfs); 2332 return (EXDEV); 2333 } 2334 2335 tdzp = VTOZ(tdvp); 2336 if (!tdzp->z_dbuf_held) { 2337 ZFS_EXIT(zfsvfs); 2338 return (EIO); 2339 } 2340 top: 2341 szp = NULL; 2342 tzp = NULL; 2343 zl = NULL; 2344 2345 /* 2346 * This is to prevent the creation of links into attribute space 2347 * by renaming a linked file into/outof an attribute directory. 2348 * See the comment in zfs_link() for why this is considered bad. 2349 */ 2350 if ((tdzp->z_phys->zp_flags & ZFS_XATTR) != 2351 (sdzp->z_phys->zp_flags & ZFS_XATTR)) { 2352 ZFS_EXIT(zfsvfs); 2353 return (EINVAL); 2354 } 2355 2356 /* 2357 * Lock source and target directory entries. To prevent deadlock, 2358 * a lock ordering must be defined. We lock the directory with 2359 * the smallest object id first, or if it's a tie, the one with 2360 * the lexically first name. 2361 */ 2362 if (sdzp->z_id < tdzp->z_id) { 2363 cmp = -1; 2364 } else if (sdzp->z_id > tdzp->z_id) { 2365 cmp = 1; 2366 } else { 2367 cmp = strcmp(snm, tnm); 2368 if (cmp == 0) { 2369 /* 2370 * POSIX: "If the old argument and the new argument 2371 * both refer to links to the same existing file, 2372 * the rename() function shall return successfully 2373 * and perform no other action." 2374 */ 2375 ZFS_EXIT(zfsvfs); 2376 return (0); 2377 } 2378 } 2379 if (cmp < 0) { 2380 serr = zfs_dirent_lock(&sdl, sdzp, snm, &szp, ZEXISTS); 2381 terr = zfs_dirent_lock(&tdl, tdzp, tnm, &tzp, 0); 2382 } else { 2383 terr = zfs_dirent_lock(&tdl, tdzp, tnm, &tzp, 0); 2384 serr = zfs_dirent_lock(&sdl, sdzp, snm, &szp, ZEXISTS); 2385 } 2386 2387 if (serr) { 2388 /* 2389 * Source entry invalid or not there. 2390 */ 2391 if (!terr) { 2392 zfs_dirent_unlock(tdl); 2393 if (tzp) 2394 VN_RELE(ZTOV(tzp)); 2395 } 2396 if (strcmp(snm, "..") == 0) 2397 serr = EINVAL; 2398 ZFS_EXIT(zfsvfs); 2399 return (serr); 2400 } 2401 if (terr) { 2402 zfs_dirent_unlock(sdl); 2403 VN_RELE(ZTOV(szp)); 2404 if (strcmp(tnm, "..") == 0) 2405 terr = EINVAL; 2406 ZFS_EXIT(zfsvfs); 2407 return (terr); 2408 } 2409 2410 /* 2411 * Must have write access at the source to remove the old entry 2412 * and write access at the target to create the new entry. 2413 * Note that if target and source are the same, this can be 2414 * done in a single check. 2415 */ 2416 2417 if (error = zfs_zaccess_rename(sdzp, szp, tdzp, tzp, cr)) 2418 goto out; 2419 2420 if (ZTOV(szp)->v_type == VDIR) { 2421 /* 2422 * Check to make sure rename is valid. 2423 * Can't do a move like this: /usr/a/b to /usr/a/b/c/d 2424 */ 2425 if (error = zfs_rename_lock(szp, tdzp, sdzp, &zl)) 2426 goto out; 2427 } 2428 2429 /* 2430 * Does target exist? 2431 */ 2432 if (tzp) { 2433 /* 2434 * Source and target must be the same type. 2435 */ 2436 if (ZTOV(szp)->v_type == VDIR) { 2437 if (ZTOV(tzp)->v_type != VDIR) { 2438 error = ENOTDIR; 2439 goto out; 2440 } 2441 } else { 2442 if (ZTOV(tzp)->v_type == VDIR) { 2443 error = EISDIR; 2444 goto out; 2445 } 2446 } 2447 /* 2448 * POSIX dictates that when the source and target 2449 * entries refer to the same file object, rename 2450 * must do nothing and exit without error. 2451 */ 2452 if (szp->z_id == tzp->z_id) { 2453 error = 0; 2454 goto out; 2455 } 2456 } 2457 2458 vnevent_rename_src(ZTOV(szp), sdvp, snm); 2459 if (tzp) 2460 vnevent_rename_dest(ZTOV(tzp), tdvp, tnm); 2461 2462 /* 2463 * notify the target directory if it is not the same 2464 * as source directory. 2465 */ 2466 if (tdvp != sdvp) { 2467 vnevent_rename_dest_dir(tdvp); 2468 } 2469 2470 tx = dmu_tx_create(zfsvfs->z_os); 2471 dmu_tx_hold_bonus(tx, szp->z_id); /* nlink changes */ 2472 dmu_tx_hold_bonus(tx, sdzp->z_id); /* nlink changes */ 2473 dmu_tx_hold_zap(tx, sdzp->z_id, FALSE, snm); 2474 dmu_tx_hold_zap(tx, tdzp->z_id, TRUE, tnm); 2475 if (sdzp != tdzp) 2476 dmu_tx_hold_bonus(tx, tdzp->z_id); /* nlink changes */ 2477 if (tzp) 2478 dmu_tx_hold_bonus(tx, tzp->z_id); /* parent changes */ 2479 dmu_tx_hold_zap(tx, zfsvfs->z_unlinkedobj, FALSE, NULL); 2480 error = dmu_tx_assign(tx, zfsvfs->z_assign); 2481 if (error) { 2482 if (zl != NULL) 2483 zfs_rename_unlock(&zl); 2484 zfs_dirent_unlock(sdl); 2485 zfs_dirent_unlock(tdl); 2486 VN_RELE(ZTOV(szp)); 2487 if (tzp) 2488 VN_RELE(ZTOV(tzp)); 2489 if (error == ERESTART && zfsvfs->z_assign == TXG_NOWAIT) { 2490 dmu_tx_wait(tx); 2491 dmu_tx_abort(tx); 2492 goto top; 2493 } 2494 dmu_tx_abort(tx); 2495 ZFS_EXIT(zfsvfs); 2496 return (error); 2497 } 2498 2499 if (tzp) /* Attempt to remove the existing target */ 2500 error = zfs_link_destroy(tdl, tzp, tx, 0, NULL); 2501 2502 if (error == 0) { 2503 error = zfs_link_create(tdl, szp, tx, ZRENAMING); 2504 if (error == 0) { 2505 error = zfs_link_destroy(sdl, szp, tx, ZRENAMING, NULL); 2506 ASSERT(error == 0); 2507 zfs_log_rename(zilog, tx, TX_RENAME, sdzp, 2508 sdl->dl_name, tdzp, tdl->dl_name, szp); 2509 } 2510 } 2511 2512 dmu_tx_commit(tx); 2513 out: 2514 if (zl != NULL) 2515 zfs_rename_unlock(&zl); 2516 2517 zfs_dirent_unlock(sdl); 2518 zfs_dirent_unlock(tdl); 2519 2520 VN_RELE(ZTOV(szp)); 2521 if (tzp) 2522 VN_RELE(ZTOV(tzp)); 2523 2524 ZFS_EXIT(zfsvfs); 2525 return (error); 2526 } 2527 2528 /* 2529 * Insert the indicated symbolic reference entry into the directory. 2530 * 2531 * IN: dvp - Directory to contain new symbolic link. 2532 * link - Name for new symlink entry. 2533 * vap - Attributes of new entry. 2534 * target - Target path of new symlink. 2535 * cr - credentials of caller. 2536 * 2537 * RETURN: 0 if success 2538 * error code if failure 2539 * 2540 * Timestamps: 2541 * dvp - ctime|mtime updated 2542 */ 2543 static int 2544 zfs_symlink(vnode_t *dvp, char *name, vattr_t *vap, char *link, cred_t *cr) 2545 { 2546 znode_t *zp, *dzp = VTOZ(dvp); 2547 zfs_dirlock_t *dl; 2548 dmu_tx_t *tx; 2549 zfsvfs_t *zfsvfs = dzp->z_zfsvfs; 2550 zilog_t *zilog; 2551 uint64_t zoid; 2552 int len = strlen(link); 2553 int error; 2554 2555 ASSERT(vap->va_type == VLNK); 2556 2557 ZFS_ENTER_VERIFY_ZP(zfsvfs, dzp); 2558 zilog = zfsvfs->z_log; 2559 top: 2560 if (error = zfs_zaccess(dzp, ACE_ADD_FILE, cr)) { 2561 ZFS_EXIT(zfsvfs); 2562 return (error); 2563 } 2564 2565 if (len > MAXPATHLEN) { 2566 ZFS_EXIT(zfsvfs); 2567 return (ENAMETOOLONG); 2568 } 2569 2570 /* 2571 * Attempt to lock directory; fail if entry already exists. 2572 */ 2573 if (error = zfs_dirent_lock(&dl, dzp, name, &zp, ZNEW)) { 2574 ZFS_EXIT(zfsvfs); 2575 return (error); 2576 } 2577 2578 tx = dmu_tx_create(zfsvfs->z_os); 2579 dmu_tx_hold_write(tx, DMU_NEW_OBJECT, 0, MAX(1, len)); 2580 dmu_tx_hold_bonus(tx, dzp->z_id); 2581 dmu_tx_hold_zap(tx, dzp->z_id, TRUE, name); 2582 if (dzp->z_phys->zp_flags & ZFS_INHERIT_ACE) 2583 dmu_tx_hold_write(tx, DMU_NEW_OBJECT, 0, SPA_MAXBLOCKSIZE); 2584 error = dmu_tx_assign(tx, zfsvfs->z_assign); 2585 if (error) { 2586 zfs_dirent_unlock(dl); 2587 if (error == ERESTART && zfsvfs->z_assign == TXG_NOWAIT) { 2588 dmu_tx_wait(tx); 2589 dmu_tx_abort(tx); 2590 goto top; 2591 } 2592 dmu_tx_abort(tx); 2593 ZFS_EXIT(zfsvfs); 2594 return (error); 2595 } 2596 2597 dmu_buf_will_dirty(dzp->z_dbuf, tx); 2598 2599 /* 2600 * Create a new object for the symlink. 2601 * Put the link content into bonus buffer if it will fit; 2602 * otherwise, store it just like any other file data. 2603 */ 2604 zoid = 0; 2605 if (sizeof (znode_phys_t) + len <= dmu_bonus_max()) { 2606 zfs_mknode(dzp, vap, &zoid, tx, cr, 0, &zp, len); 2607 if (len != 0) 2608 bcopy(link, zp->z_phys + 1, len); 2609 } else { 2610 dmu_buf_t *dbp; 2611 2612 zfs_mknode(dzp, vap, &zoid, tx, cr, 0, &zp, 0); 2613 2614 /* 2615 * Nothing can access the znode yet so no locking needed 2616 * for growing the znode's blocksize. 2617 */ 2618 zfs_grow_blocksize(zp, len, tx); 2619 2620 VERIFY(0 == dmu_buf_hold(zfsvfs->z_os, zoid, 0, FTAG, &dbp)); 2621 dmu_buf_will_dirty(dbp, tx); 2622 2623 ASSERT3U(len, <=, dbp->db_size); 2624 bcopy(link, dbp->db_data, len); 2625 dmu_buf_rele(dbp, FTAG); 2626 } 2627 zp->z_phys->zp_size = len; 2628 2629 /* 2630 * Insert the new object into the directory. 2631 */ 2632 (void) zfs_link_create(dl, zp, tx, ZNEW); 2633 out: 2634 if (error == 0) 2635 zfs_log_symlink(zilog, tx, TX_SYMLINK, dzp, zp, name, link); 2636 2637 dmu_tx_commit(tx); 2638 2639 zfs_dirent_unlock(dl); 2640 2641 VN_RELE(ZTOV(zp)); 2642 2643 ZFS_EXIT(zfsvfs); 2644 return (error); 2645 } 2646 2647 /* 2648 * Return, in the buffer contained in the provided uio structure, 2649 * the symbolic path referred to by vp. 2650 * 2651 * IN: vp - vnode of symbolic link. 2652 * uoip - structure to contain the link path. 2653 * cr - credentials of caller. 2654 * 2655 * OUT: uio - structure to contain the link path. 2656 * 2657 * RETURN: 0 if success 2658 * error code if failure 2659 * 2660 * Timestamps: 2661 * vp - atime updated 2662 */ 2663 /* ARGSUSED */ 2664 static int 2665 zfs_readlink(vnode_t *vp, uio_t *uio, cred_t *cr) 2666 { 2667 znode_t *zp = VTOZ(vp); 2668 zfsvfs_t *zfsvfs = zp->z_zfsvfs; 2669 size_t bufsz; 2670 int error; 2671 2672 ZFS_ENTER_VERIFY_ZP(zfsvfs, zp); 2673 2674 bufsz = (size_t)zp->z_phys->zp_size; 2675 if (bufsz + sizeof (znode_phys_t) <= zp->z_dbuf->db_size) { 2676 error = uiomove(zp->z_phys + 1, 2677 MIN((size_t)bufsz, uio->uio_resid), UIO_READ, uio); 2678 } else { 2679 dmu_buf_t *dbp; 2680 error = dmu_buf_hold(zfsvfs->z_os, zp->z_id, 0, FTAG, &dbp); 2681 if (error) { 2682 ZFS_EXIT(zfsvfs); 2683 return (error); 2684 } 2685 error = uiomove(dbp->db_data, 2686 MIN((size_t)bufsz, uio->uio_resid), UIO_READ, uio); 2687 dmu_buf_rele(dbp, FTAG); 2688 } 2689 2690 ZFS_ACCESSTIME_STAMP(zfsvfs, zp); 2691 ZFS_EXIT(zfsvfs); 2692 return (error); 2693 } 2694 2695 /* 2696 * Insert a new entry into directory tdvp referencing svp. 2697 * 2698 * IN: tdvp - Directory to contain new entry. 2699 * svp - vnode of new entry. 2700 * name - name of new entry. 2701 * cr - credentials of caller. 2702 * 2703 * RETURN: 0 if success 2704 * error code if failure 2705 * 2706 * Timestamps: 2707 * tdvp - ctime|mtime updated 2708 * svp - ctime updated 2709 */ 2710 /* ARGSUSED */ 2711 static int 2712 zfs_link(vnode_t *tdvp, vnode_t *svp, char *name, cred_t *cr) 2713 { 2714 znode_t *dzp = VTOZ(tdvp); 2715 znode_t *tzp, *szp; 2716 zfsvfs_t *zfsvfs = dzp->z_zfsvfs; 2717 zilog_t *zilog; 2718 zfs_dirlock_t *dl; 2719 dmu_tx_t *tx; 2720 vnode_t *realvp; 2721 int error; 2722 2723 ASSERT(tdvp->v_type == VDIR); 2724 2725 ZFS_ENTER_VERIFY_ZP(zfsvfs, dzp); 2726 zilog = zfsvfs->z_log; 2727 2728 if (VOP_REALVP(svp, &realvp) == 0) 2729 svp = realvp; 2730 2731 if (svp->v_vfsp != tdvp->v_vfsp) { 2732 ZFS_EXIT(zfsvfs); 2733 return (EXDEV); 2734 } 2735 2736 szp = VTOZ(svp); 2737 if (!szp->z_dbuf_held) { 2738 ZFS_EXIT(zfsvfs); 2739 return (EIO); 2740 } 2741 top: 2742 /* 2743 * We do not support links between attributes and non-attributes 2744 * because of the potential security risk of creating links 2745 * into "normal" file space in order to circumvent restrictions 2746 * imposed in attribute space. 2747 */ 2748 if ((szp->z_phys->zp_flags & ZFS_XATTR) != 2749 (dzp->z_phys->zp_flags & ZFS_XATTR)) { 2750 ZFS_EXIT(zfsvfs); 2751 return (EINVAL); 2752 } 2753 2754 /* 2755 * POSIX dictates that we return EPERM here. 2756 * Better choices include ENOTSUP or EISDIR. 2757 */ 2758 if (svp->v_type == VDIR) { 2759 ZFS_EXIT(zfsvfs); 2760 return (EPERM); 2761 } 2762 2763 if ((uid_t)szp->z_phys->zp_uid != crgetuid(cr) && 2764 secpolicy_basic_link(cr) != 0) { 2765 ZFS_EXIT(zfsvfs); 2766 return (EPERM); 2767 } 2768 2769 if (error = zfs_zaccess(dzp, ACE_ADD_FILE, cr)) { 2770 ZFS_EXIT(zfsvfs); 2771 return (error); 2772 } 2773 2774 /* 2775 * Attempt to lock directory; fail if entry already exists. 2776 */ 2777 if (error = zfs_dirent_lock(&dl, dzp, name, &tzp, ZNEW)) { 2778 ZFS_EXIT(zfsvfs); 2779 return (error); 2780 } 2781 2782 tx = dmu_tx_create(zfsvfs->z_os); 2783 dmu_tx_hold_bonus(tx, szp->z_id); 2784 dmu_tx_hold_zap(tx, dzp->z_id, TRUE, name); 2785 error = dmu_tx_assign(tx, zfsvfs->z_assign); 2786 if (error) { 2787 zfs_dirent_unlock(dl); 2788 if (error == ERESTART && zfsvfs->z_assign == TXG_NOWAIT) { 2789 dmu_tx_wait(tx); 2790 dmu_tx_abort(tx); 2791 goto top; 2792 } 2793 dmu_tx_abort(tx); 2794 ZFS_EXIT(zfsvfs); 2795 return (error); 2796 } 2797 2798 error = zfs_link_create(dl, szp, tx, 0); 2799 2800 if (error == 0) 2801 zfs_log_link(zilog, tx, TX_LINK, dzp, szp, name); 2802 2803 dmu_tx_commit(tx); 2804 2805 zfs_dirent_unlock(dl); 2806 2807 if (error == 0) { 2808 vnevent_link(svp); 2809 } 2810 2811 ZFS_EXIT(zfsvfs); 2812 return (error); 2813 } 2814 2815 /* 2816 * zfs_null_putapage() is used when the file system has been force 2817 * unmounted. It just drops the pages. 2818 */ 2819 /* ARGSUSED */ 2820 static int 2821 zfs_null_putapage(vnode_t *vp, page_t *pp, u_offset_t *offp, 2822 size_t *lenp, int flags, cred_t *cr) 2823 { 2824 pvn_write_done(pp, B_INVAL|B_FORCE|B_ERROR); 2825 return (0); 2826 } 2827 2828 /* 2829 * Push a page out to disk, klustering if possible. 2830 * 2831 * IN: vp - file to push page to. 2832 * pp - page to push. 2833 * flags - additional flags. 2834 * cr - credentials of caller. 2835 * 2836 * OUT: offp - start of range pushed. 2837 * lenp - len of range pushed. 2838 * 2839 * RETURN: 0 if success 2840 * error code if failure 2841 * 2842 * NOTE: callers must have locked the page to be pushed. On 2843 * exit, the page (and all other pages in the kluster) must be 2844 * unlocked. 2845 */ 2846 /* ARGSUSED */ 2847 static int 2848 zfs_putapage(vnode_t *vp, page_t *pp, u_offset_t *offp, 2849 size_t *lenp, int flags, cred_t *cr) 2850 { 2851 znode_t *zp = VTOZ(vp); 2852 zfsvfs_t *zfsvfs = zp->z_zfsvfs; 2853 zilog_t *zilog = zfsvfs->z_log; 2854 dmu_tx_t *tx; 2855 rl_t *rl; 2856 u_offset_t off, koff; 2857 size_t len, klen; 2858 uint64_t filesz; 2859 int err; 2860 2861 filesz = zp->z_phys->zp_size; 2862 off = pp->p_offset; 2863 len = PAGESIZE; 2864 /* 2865 * If our blocksize is bigger than the page size, try to kluster 2866 * muiltiple pages so that we write a full block (thus avoiding 2867 * a read-modify-write). 2868 */ 2869 if (off < filesz && zp->z_blksz > PAGESIZE) { 2870 if (!ISP2(zp->z_blksz)) { 2871 /* Only one block in the file. */ 2872 klen = P2ROUNDUP((ulong_t)zp->z_blksz, PAGESIZE); 2873 koff = 0; 2874 } else { 2875 klen = zp->z_blksz; 2876 koff = P2ALIGN(off, (u_offset_t)klen); 2877 } 2878 ASSERT(koff <= filesz); 2879 if (koff + klen > filesz) 2880 klen = P2ROUNDUP(filesz - koff, (uint64_t)PAGESIZE); 2881 pp = pvn_write_kluster(vp, pp, &off, &len, koff, klen, flags); 2882 } 2883 ASSERT3U(btop(len), ==, btopr(len)); 2884 top: 2885 rl = zfs_range_lock(zp, off, len, RL_WRITER); 2886 /* 2887 * Can't push pages past end-of-file. 2888 */ 2889 filesz = zp->z_phys->zp_size; 2890 if (off >= filesz) { 2891 /* ignore all pages */ 2892 err = 0; 2893 goto out; 2894 } else if (off + len > filesz) { 2895 int npages = btopr(filesz - off); 2896 page_t *trunc; 2897 2898 page_list_break(&pp, &trunc, npages); 2899 /* ignore pages past end of file */ 2900 if (trunc) 2901 pvn_write_done(trunc, flags); 2902 len = filesz - off; 2903 } 2904 2905 tx = dmu_tx_create(zfsvfs->z_os); 2906 dmu_tx_hold_write(tx, zp->z_id, off, len); 2907 dmu_tx_hold_bonus(tx, zp->z_id); 2908 err = dmu_tx_assign(tx, zfsvfs->z_assign); 2909 if (err != 0) { 2910 if (err == ERESTART && zfsvfs->z_assign == TXG_NOWAIT) { 2911 zfs_range_unlock(rl); 2912 dmu_tx_wait(tx); 2913 dmu_tx_abort(tx); 2914 err = 0; 2915 goto top; 2916 } 2917 dmu_tx_abort(tx); 2918 goto out; 2919 } 2920 2921 if (zp->z_blksz <= PAGESIZE) { 2922 caddr_t va = ppmapin(pp, PROT_READ, (caddr_t)-1); 2923 ASSERT3U(len, <=, PAGESIZE); 2924 dmu_write(zfsvfs->z_os, zp->z_id, off, len, va, tx); 2925 ppmapout(va); 2926 } else { 2927 err = dmu_write_pages(zfsvfs->z_os, zp->z_id, off, len, pp, tx); 2928 } 2929 2930 if (err == 0) { 2931 zfs_time_stamper(zp, CONTENT_MODIFIED, tx); 2932 zfs_log_write(zilog, tx, TX_WRITE, zp, off, len, 0); 2933 dmu_tx_commit(tx); 2934 } 2935 2936 out: 2937 zfs_range_unlock(rl); 2938 pvn_write_done(pp, (err ? B_ERROR : 0) | flags); 2939 if (offp) 2940 *offp = off; 2941 if (lenp) 2942 *lenp = len; 2943 2944 return (err); 2945 } 2946 2947 /* 2948 * Copy the portion of the file indicated from pages into the file. 2949 * The pages are stored in a page list attached to the files vnode. 2950 * 2951 * IN: vp - vnode of file to push page data to. 2952 * off - position in file to put data. 2953 * len - amount of data to write. 2954 * flags - flags to control the operation. 2955 * cr - credentials of caller. 2956 * 2957 * RETURN: 0 if success 2958 * error code if failure 2959 * 2960 * Timestamps: 2961 * vp - ctime|mtime updated 2962 */ 2963 static int 2964 zfs_putpage(vnode_t *vp, offset_t off, size_t len, int flags, cred_t *cr) 2965 { 2966 znode_t *zp = VTOZ(vp); 2967 zfsvfs_t *zfsvfs = zp->z_zfsvfs; 2968 page_t *pp; 2969 size_t io_len; 2970 u_offset_t io_off; 2971 uint64_t filesz; 2972 int error = 0; 2973 2974 ZFS_ENTER_VERIFY_ZP(zfsvfs, zp); 2975 2976 ASSERT(zp->z_dbuf_held && zp->z_phys); 2977 2978 if (len == 0) { 2979 /* 2980 * Search the entire vp list for pages >= off. 2981 */ 2982 error = pvn_vplist_dirty(vp, (u_offset_t)off, zfs_putapage, 2983 flags, cr); 2984 goto out; 2985 } 2986 2987 filesz = zp->z_phys->zp_size; /* get consistent copy of zp_size */ 2988 if (off > filesz) { 2989 /* past end of file */ 2990 ZFS_EXIT(zfsvfs); 2991 return (0); 2992 } 2993 2994 len = MIN(len, filesz - off); 2995 2996 for (io_off = off; io_off < off + len; io_off += io_len) { 2997 if ((flags & B_INVAL) || ((flags & B_ASYNC) == 0)) { 2998 pp = page_lookup(vp, io_off, 2999 (flags & (B_INVAL | B_FREE)) ? SE_EXCL : SE_SHARED); 3000 } else { 3001 pp = page_lookup_nowait(vp, io_off, 3002 (flags & B_FREE) ? SE_EXCL : SE_SHARED); 3003 } 3004 3005 if (pp != NULL && pvn_getdirty(pp, flags)) { 3006 int err; 3007 3008 /* 3009 * Found a dirty page to push 3010 */ 3011 err = zfs_putapage(vp, pp, &io_off, &io_len, flags, cr); 3012 if (err) 3013 error = err; 3014 } else { 3015 io_len = PAGESIZE; 3016 } 3017 } 3018 out: 3019 if ((flags & B_ASYNC) == 0) 3020 zil_commit(zfsvfs->z_log, UINT64_MAX, zp->z_id); 3021 ZFS_EXIT(zfsvfs); 3022 return (error); 3023 } 3024 3025 void 3026 zfs_inactive(vnode_t *vp, cred_t *cr) 3027 { 3028 znode_t *zp = VTOZ(vp); 3029 zfsvfs_t *zfsvfs = zp->z_zfsvfs; 3030 int error; 3031 3032 rw_enter(&zfsvfs->z_teardown_inactive_lock, RW_READER); 3033 if (zp->z_dbuf_held == 0) { 3034 if (vn_has_cached_data(vp)) { 3035 (void) pvn_vplist_dirty(vp, 0, zfs_null_putapage, 3036 B_INVAL, cr); 3037 } 3038 3039 mutex_enter(&zp->z_lock); 3040 vp->v_count = 0; /* count arrives as 1 */ 3041 if (zp->z_dbuf == NULL) { 3042 mutex_exit(&zp->z_lock); 3043 zfs_znode_free(zp); 3044 } else { 3045 mutex_exit(&zp->z_lock); 3046 } 3047 rw_exit(&zfsvfs->z_teardown_inactive_lock); 3048 VFS_RELE(zfsvfs->z_vfs); 3049 return; 3050 } 3051 3052 /* 3053 * Attempt to push any data in the page cache. If this fails 3054 * we will get kicked out later in zfs_zinactive(). 3055 */ 3056 if (vn_has_cached_data(vp)) { 3057 (void) pvn_vplist_dirty(vp, 0, zfs_putapage, B_INVAL|B_ASYNC, 3058 cr); 3059 } 3060 3061 if (zp->z_atime_dirty && zp->z_unlinked == 0) { 3062 dmu_tx_t *tx = dmu_tx_create(zfsvfs->z_os); 3063 3064 dmu_tx_hold_bonus(tx, zp->z_id); 3065 error = dmu_tx_assign(tx, TXG_WAIT); 3066 if (error) { 3067 dmu_tx_abort(tx); 3068 } else { 3069 dmu_buf_will_dirty(zp->z_dbuf, tx); 3070 mutex_enter(&zp->z_lock); 3071 zp->z_atime_dirty = 0; 3072 mutex_exit(&zp->z_lock); 3073 dmu_tx_commit(tx); 3074 } 3075 } 3076 3077 zfs_zinactive(zp); 3078 rw_exit(&zfsvfs->z_teardown_inactive_lock); 3079 } 3080 3081 /* 3082 * Bounds-check the seek operation. 3083 * 3084 * IN: vp - vnode seeking within 3085 * ooff - old file offset 3086 * noffp - pointer to new file offset 3087 * 3088 * RETURN: 0 if success 3089 * EINVAL if new offset invalid 3090 */ 3091 /* ARGSUSED */ 3092 static int 3093 zfs_seek(vnode_t *vp, offset_t ooff, offset_t *noffp) 3094 { 3095 if (vp->v_type == VDIR) 3096 return (0); 3097 return ((*noffp < 0 || *noffp > MAXOFFSET_T) ? EINVAL : 0); 3098 } 3099 3100 /* 3101 * Pre-filter the generic locking function to trap attempts to place 3102 * a mandatory lock on a memory mapped file. 3103 */ 3104 static int 3105 zfs_frlock(vnode_t *vp, int cmd, flock64_t *bfp, int flag, offset_t offset, 3106 flk_callback_t *flk_cbp, cred_t *cr) 3107 { 3108 znode_t *zp = VTOZ(vp); 3109 zfsvfs_t *zfsvfs = zp->z_zfsvfs; 3110 int error; 3111 3112 ZFS_ENTER_VERIFY_ZP(zfsvfs, zp); 3113 3114 /* 3115 * We are following the UFS semantics with respect to mapcnt 3116 * here: If we see that the file is mapped already, then we will 3117 * return an error, but we don't worry about races between this 3118 * function and zfs_map(). 3119 */ 3120 if (zp->z_mapcnt > 0 && MANDMODE((mode_t)zp->z_phys->zp_mode)) { 3121 ZFS_EXIT(zfsvfs); 3122 return (EAGAIN); 3123 } 3124 error = fs_frlock(vp, cmd, bfp, flag, offset, flk_cbp, cr); 3125 ZFS_EXIT(zfsvfs); 3126 return (error); 3127 } 3128 3129 /* 3130 * If we can't find a page in the cache, we will create a new page 3131 * and fill it with file data. For efficiency, we may try to fill 3132 * multiple pages at once (klustering). 3133 */ 3134 static int 3135 zfs_fillpage(vnode_t *vp, u_offset_t off, struct seg *seg, 3136 caddr_t addr, page_t *pl[], size_t plsz, enum seg_rw rw) 3137 { 3138 znode_t *zp = VTOZ(vp); 3139 page_t *pp, *cur_pp; 3140 objset_t *os = zp->z_zfsvfs->z_os; 3141 caddr_t va; 3142 u_offset_t io_off, total; 3143 uint64_t oid = zp->z_id; 3144 size_t io_len; 3145 uint64_t filesz; 3146 int err; 3147 3148 /* 3149 * If we are only asking for a single page don't bother klustering. 3150 */ 3151 filesz = zp->z_phys->zp_size; /* get consistent copy of zp_size */ 3152 if (off >= filesz) 3153 return (EFAULT); 3154 if (plsz == PAGESIZE || zp->z_blksz <= PAGESIZE) { 3155 io_off = off; 3156 io_len = PAGESIZE; 3157 pp = page_create_va(vp, io_off, io_len, PG_WAIT, seg, addr); 3158 } else { 3159 /* 3160 * Try to fill a kluster of pages (a blocks worth). 3161 */ 3162 size_t klen; 3163 u_offset_t koff; 3164 3165 if (!ISP2(zp->z_blksz)) { 3166 /* Only one block in the file. */ 3167 klen = P2ROUNDUP((ulong_t)zp->z_blksz, PAGESIZE); 3168 koff = 0; 3169 } else { 3170 /* 3171 * It would be ideal to align our offset to the 3172 * blocksize but doing so has resulted in some 3173 * strange application crashes. For now, we 3174 * leave the offset as is and only adjust the 3175 * length if we are off the end of the file. 3176 */ 3177 koff = off; 3178 klen = plsz; 3179 } 3180 ASSERT(koff <= filesz); 3181 if (koff + klen > filesz) 3182 klen = P2ROUNDUP(filesz, (uint64_t)PAGESIZE) - koff; 3183 ASSERT3U(off, >=, koff); 3184 ASSERT3U(off, <, koff + klen); 3185 pp = pvn_read_kluster(vp, off, seg, addr, &io_off, 3186 &io_len, koff, klen, 0); 3187 } 3188 if (pp == NULL) { 3189 /* 3190 * Some other thread entered the page before us. 3191 * Return to zfs_getpage to retry the lookup. 3192 */ 3193 *pl = NULL; 3194 return (0); 3195 } 3196 3197 /* 3198 * Fill the pages in the kluster. 3199 */ 3200 cur_pp = pp; 3201 for (total = io_off + io_len; io_off < total; io_off += PAGESIZE) { 3202 ASSERT3U(io_off, ==, cur_pp->p_offset); 3203 va = ppmapin(cur_pp, PROT_READ | PROT_WRITE, (caddr_t)-1); 3204 err = dmu_read(os, oid, io_off, PAGESIZE, va); 3205 ppmapout(va); 3206 if (err) { 3207 /* On error, toss the entire kluster */ 3208 pvn_read_done(pp, B_ERROR); 3209 return (err); 3210 } 3211 cur_pp = cur_pp->p_next; 3212 } 3213 out: 3214 /* 3215 * Fill in the page list array from the kluster. If 3216 * there are too many pages in the kluster, return 3217 * as many pages as possible starting from the desired 3218 * offset `off'. 3219 * NOTE: the page list will always be null terminated. 3220 */ 3221 pvn_plist_init(pp, pl, plsz, off, io_len, rw); 3222 3223 return (0); 3224 } 3225 3226 /* 3227 * Return pointers to the pages for the file region [off, off + len] 3228 * in the pl array. If plsz is greater than len, this function may 3229 * also return page pointers from before or after the specified 3230 * region (i.e. some region [off', off' + plsz]). These additional 3231 * pages are only returned if they are already in the cache, or were 3232 * created as part of a klustered read. 3233 * 3234 * IN: vp - vnode of file to get data from. 3235 * off - position in file to get data from. 3236 * len - amount of data to retrieve. 3237 * plsz - length of provided page list. 3238 * seg - segment to obtain pages for. 3239 * addr - virtual address of fault. 3240 * rw - mode of created pages. 3241 * cr - credentials of caller. 3242 * 3243 * OUT: protp - protection mode of created pages. 3244 * pl - list of pages created. 3245 * 3246 * RETURN: 0 if success 3247 * error code if failure 3248 * 3249 * Timestamps: 3250 * vp - atime updated 3251 */ 3252 /* ARGSUSED */ 3253 static int 3254 zfs_getpage(vnode_t *vp, offset_t off, size_t len, uint_t *protp, 3255 page_t *pl[], size_t plsz, struct seg *seg, caddr_t addr, 3256 enum seg_rw rw, cred_t *cr) 3257 { 3258 znode_t *zp = VTOZ(vp); 3259 zfsvfs_t *zfsvfs = zp->z_zfsvfs; 3260 page_t *pp, **pl0 = pl; 3261 int need_unlock = 0, err = 0; 3262 offset_t orig_off; 3263 3264 ZFS_ENTER_VERIFY_ZP(zfsvfs, zp); 3265 3266 if (protp) 3267 *protp = PROT_ALL; 3268 3269 ASSERT(zp->z_dbuf_held && zp->z_phys); 3270 3271 /* no faultahead (for now) */ 3272 if (pl == NULL) { 3273 ZFS_EXIT(zfsvfs); 3274 return (0); 3275 } 3276 3277 /* can't fault past EOF */ 3278 if (off >= zp->z_phys->zp_size) { 3279 ZFS_EXIT(zfsvfs); 3280 return (EFAULT); 3281 } 3282 orig_off = off; 3283 3284 /* 3285 * If we already own the lock, then we must be page faulting 3286 * in the middle of a write to this file (i.e., we are writing 3287 * to this file using data from a mapped region of the file). 3288 */ 3289 if (rw_owner(&zp->z_map_lock) != curthread) { 3290 rw_enter(&zp->z_map_lock, RW_WRITER); 3291 need_unlock = TRUE; 3292 } 3293 3294 /* 3295 * Loop through the requested range [off, off + len] looking 3296 * for pages. If we don't find a page, we will need to create 3297 * a new page and fill it with data from the file. 3298 */ 3299 while (len > 0) { 3300 if (plsz < PAGESIZE) 3301 break; 3302 if (pp = page_lookup(vp, off, SE_SHARED)) { 3303 *pl++ = pp; 3304 off += PAGESIZE; 3305 addr += PAGESIZE; 3306 len -= PAGESIZE; 3307 plsz -= PAGESIZE; 3308 } else { 3309 err = zfs_fillpage(vp, off, seg, addr, pl, plsz, rw); 3310 if (err) 3311 goto out; 3312 /* 3313 * klustering may have changed our region 3314 * to be block aligned. 3315 */ 3316 if (((pp = *pl) != 0) && (off != pp->p_offset)) { 3317 int delta = off - pp->p_offset; 3318 len += delta; 3319 off -= delta; 3320 addr -= delta; 3321 } 3322 while (*pl) { 3323 pl++; 3324 off += PAGESIZE; 3325 addr += PAGESIZE; 3326 plsz -= PAGESIZE; 3327 if (len > PAGESIZE) 3328 len -= PAGESIZE; 3329 else 3330 len = 0; 3331 } 3332 } 3333 } 3334 3335 /* 3336 * Fill out the page array with any pages already in the cache. 3337 */ 3338 while (plsz > 0) { 3339 pp = page_lookup_nowait(vp, off, SE_SHARED); 3340 if (pp == NULL) 3341 break; 3342 *pl++ = pp; 3343 off += PAGESIZE; 3344 plsz -= PAGESIZE; 3345 } 3346 3347 ZFS_ACCESSTIME_STAMP(zfsvfs, zp); 3348 out: 3349 /* 3350 * We can't grab the range lock for the page as reader which would 3351 * stop truncation as this leads to deadlock. So we need to recheck 3352 * the file size. 3353 */ 3354 if (orig_off >= zp->z_phys->zp_size) 3355 err = EFAULT; 3356 if (err) { 3357 /* 3358 * Release any pages we have previously locked. 3359 */ 3360 while (pl > pl0) 3361 page_unlock(*--pl); 3362 } 3363 3364 *pl = NULL; 3365 3366 if (need_unlock) 3367 rw_exit(&zp->z_map_lock); 3368 3369 ZFS_EXIT(zfsvfs); 3370 return (err); 3371 } 3372 3373 /* 3374 * Request a memory map for a section of a file. This code interacts 3375 * with common code and the VM system as follows: 3376 * 3377 * common code calls mmap(), which ends up in smmap_common() 3378 * 3379 * this calls VOP_MAP(), which takes you into (say) zfs 3380 * 3381 * zfs_map() calls as_map(), passing segvn_create() as the callback 3382 * 3383 * segvn_create() creates the new segment and calls VOP_ADDMAP() 3384 * 3385 * zfs_addmap() updates z_mapcnt 3386 */ 3387 static int 3388 zfs_map(vnode_t *vp, offset_t off, struct as *as, caddr_t *addrp, 3389 size_t len, uchar_t prot, uchar_t maxprot, uint_t flags, cred_t *cr) 3390 { 3391 znode_t *zp = VTOZ(vp); 3392 zfsvfs_t *zfsvfs = zp->z_zfsvfs; 3393 segvn_crargs_t vn_a; 3394 int error; 3395 3396 ZFS_ENTER_VERIFY_ZP(zfsvfs, zp); 3397 3398 if (vp->v_flag & VNOMAP) { 3399 ZFS_EXIT(zfsvfs); 3400 return (ENOSYS); 3401 } 3402 3403 if (off < 0 || len > MAXOFFSET_T - off) { 3404 ZFS_EXIT(zfsvfs); 3405 return (ENXIO); 3406 } 3407 3408 if (vp->v_type != VREG) { 3409 ZFS_EXIT(zfsvfs); 3410 return (ENODEV); 3411 } 3412 3413 /* 3414 * If file is locked, disallow mapping. 3415 */ 3416 if (MANDMODE((mode_t)zp->z_phys->zp_mode) && vn_has_flocks(vp)) { 3417 ZFS_EXIT(zfsvfs); 3418 return (EAGAIN); 3419 } 3420 3421 as_rangelock(as); 3422 if ((flags & MAP_FIXED) == 0) { 3423 map_addr(addrp, len, off, 1, flags); 3424 if (*addrp == NULL) { 3425 as_rangeunlock(as); 3426 ZFS_EXIT(zfsvfs); 3427 return (ENOMEM); 3428 } 3429 } else { 3430 /* 3431 * User specified address - blow away any previous mappings 3432 */ 3433 (void) as_unmap(as, *addrp, len); 3434 } 3435 3436 vn_a.vp = vp; 3437 vn_a.offset = (u_offset_t)off; 3438 vn_a.type = flags & MAP_TYPE; 3439 vn_a.prot = prot; 3440 vn_a.maxprot = maxprot; 3441 vn_a.cred = cr; 3442 vn_a.amp = NULL; 3443 vn_a.flags = flags & ~MAP_TYPE; 3444 vn_a.szc = 0; 3445 vn_a.lgrp_mem_policy_flags = 0; 3446 3447 error = as_map(as, *addrp, len, segvn_create, &vn_a); 3448 3449 as_rangeunlock(as); 3450 ZFS_EXIT(zfsvfs); 3451 return (error); 3452 } 3453 3454 /* ARGSUSED */ 3455 static int 3456 zfs_addmap(vnode_t *vp, offset_t off, struct as *as, caddr_t addr, 3457 size_t len, uchar_t prot, uchar_t maxprot, uint_t flags, cred_t *cr) 3458 { 3459 uint64_t pages = btopr(len); 3460 3461 atomic_add_64(&VTOZ(vp)->z_mapcnt, pages); 3462 return (0); 3463 } 3464 3465 /* 3466 * The reason we push dirty pages as part of zfs_delmap() is so that we get a 3467 * more accurate mtime for the associated file. Since we don't have a way of 3468 * detecting when the data was actually modified, we have to resort to 3469 * heuristics. If an explicit msync() is done, then we mark the mtime when the 3470 * last page is pushed. The problem occurs when the msync() call is omitted, 3471 * which by far the most common case: 3472 * 3473 * open() 3474 * mmap() 3475 * <modify memory> 3476 * munmap() 3477 * close() 3478 * <time lapse> 3479 * putpage() via fsflush 3480 * 3481 * If we wait until fsflush to come along, we can have a modification time that 3482 * is some arbitrary point in the future. In order to prevent this in the 3483 * common case, we flush pages whenever a (MAP_SHARED, PROT_WRITE) mapping is 3484 * torn down. 3485 */ 3486 /* ARGSUSED */ 3487 static int 3488 zfs_delmap(vnode_t *vp, offset_t off, struct as *as, caddr_t addr, 3489 size_t len, uint_t prot, uint_t maxprot, uint_t flags, cred_t *cr) 3490 { 3491 uint64_t pages = btopr(len); 3492 3493 ASSERT3U(VTOZ(vp)->z_mapcnt, >=, pages); 3494 atomic_add_64(&VTOZ(vp)->z_mapcnt, -pages); 3495 3496 if ((flags & MAP_SHARED) && (prot & PROT_WRITE) && 3497 vn_has_cached_data(vp)) 3498 (void) VOP_PUTPAGE(vp, off, len, B_ASYNC, cr); 3499 3500 return (0); 3501 } 3502 3503 /* 3504 * Free or allocate space in a file. Currently, this function only 3505 * supports the `F_FREESP' command. However, this command is somewhat 3506 * misnamed, as its functionality includes the ability to allocate as 3507 * well as free space. 3508 * 3509 * IN: vp - vnode of file to free data in. 3510 * cmd - action to take (only F_FREESP supported). 3511 * bfp - section of file to free/alloc. 3512 * flag - current file open mode flags. 3513 * offset - current file offset. 3514 * cr - credentials of caller [UNUSED]. 3515 * 3516 * RETURN: 0 if success 3517 * error code if failure 3518 * 3519 * Timestamps: 3520 * vp - ctime|mtime updated 3521 */ 3522 /* ARGSUSED */ 3523 static int 3524 zfs_space(vnode_t *vp, int cmd, flock64_t *bfp, int flag, 3525 offset_t offset, cred_t *cr, caller_context_t *ct) 3526 { 3527 znode_t *zp = VTOZ(vp); 3528 zfsvfs_t *zfsvfs = zp->z_zfsvfs; 3529 uint64_t off, len; 3530 int error; 3531 3532 ZFS_ENTER_VERIFY_ZP(zfsvfs, zp); 3533 3534 top: 3535 if (cmd != F_FREESP) { 3536 ZFS_EXIT(zfsvfs); 3537 return (EINVAL); 3538 } 3539 3540 if (error = convoff(vp, bfp, 0, offset)) { 3541 ZFS_EXIT(zfsvfs); 3542 return (error); 3543 } 3544 3545 if (bfp->l_len < 0) { 3546 ZFS_EXIT(zfsvfs); 3547 return (EINVAL); 3548 } 3549 3550 off = bfp->l_start; 3551 len = bfp->l_len; /* 0 means from off to end of file */ 3552 3553 do { 3554 error = zfs_freesp(zp, off, len, flag, TRUE); 3555 /* NB: we already did dmu_tx_wait() if necessary */ 3556 } while (error == ERESTART && zfsvfs->z_assign == TXG_NOWAIT); 3557 3558 ZFS_EXIT(zfsvfs); 3559 return (error); 3560 } 3561 3562 static int 3563 zfs_fid(vnode_t *vp, fid_t *fidp) 3564 { 3565 znode_t *zp = VTOZ(vp); 3566 zfsvfs_t *zfsvfs = zp->z_zfsvfs; 3567 uint32_t gen; 3568 uint64_t object = zp->z_id; 3569 zfid_short_t *zfid; 3570 int size, i; 3571 3572 ZFS_ENTER_VERIFY_ZP(zfsvfs, zp); 3573 gen = (uint32_t)zp->z_gen; 3574 3575 size = (zfsvfs->z_parent != zfsvfs) ? LONG_FID_LEN : SHORT_FID_LEN; 3576 if (fidp->fid_len < size) { 3577 fidp->fid_len = size; 3578 ZFS_EXIT(zfsvfs); 3579 return (ENOSPC); 3580 } 3581 3582 zfid = (zfid_short_t *)fidp; 3583 3584 zfid->zf_len = size; 3585 3586 for (i = 0; i < sizeof (zfid->zf_object); i++) 3587 zfid->zf_object[i] = (uint8_t)(object >> (8 * i)); 3588 3589 /* Must have a non-zero generation number to distinguish from .zfs */ 3590 if (gen == 0) 3591 gen = 1; 3592 for (i = 0; i < sizeof (zfid->zf_gen); i++) 3593 zfid->zf_gen[i] = (uint8_t)(gen >> (8 * i)); 3594 3595 if (size == LONG_FID_LEN) { 3596 uint64_t objsetid = dmu_objset_id(zfsvfs->z_os); 3597 zfid_long_t *zlfid; 3598 3599 zlfid = (zfid_long_t *)fidp; 3600 3601 for (i = 0; i < sizeof (zlfid->zf_setid); i++) 3602 zlfid->zf_setid[i] = (uint8_t)(objsetid >> (8 * i)); 3603 3604 /* XXX - this should be the generation number for the objset */ 3605 for (i = 0; i < sizeof (zlfid->zf_setgen); i++) 3606 zlfid->zf_setgen[i] = 0; 3607 } 3608 3609 ZFS_EXIT(zfsvfs); 3610 return (0); 3611 } 3612 3613 static int 3614 zfs_pathconf(vnode_t *vp, int cmd, ulong_t *valp, cred_t *cr) 3615 { 3616 znode_t *zp, *xzp; 3617 zfsvfs_t *zfsvfs; 3618 zfs_dirlock_t *dl; 3619 int error; 3620 3621 switch (cmd) { 3622 case _PC_LINK_MAX: 3623 *valp = ULONG_MAX; 3624 return (0); 3625 3626 case _PC_FILESIZEBITS: 3627 *valp = 64; 3628 return (0); 3629 3630 case _PC_XATTR_EXISTS: 3631 zp = VTOZ(vp); 3632 zfsvfs = zp->z_zfsvfs; 3633 ZFS_ENTER_VERIFY_ZP(zfsvfs, zp); 3634 *valp = 0; 3635 error = zfs_dirent_lock(&dl, zp, "", &xzp, 3636 ZXATTR | ZEXISTS | ZSHARED); 3637 if (error == 0) { 3638 zfs_dirent_unlock(dl); 3639 if (!zfs_dirempty(xzp)) 3640 *valp = 1; 3641 VN_RELE(ZTOV(xzp)); 3642 } else if (error == ENOENT) { 3643 /* 3644 * If there aren't extended attributes, it's the 3645 * same as having zero of them. 3646 */ 3647 error = 0; 3648 } 3649 ZFS_EXIT(zfsvfs); 3650 return (error); 3651 3652 case _PC_ACL_ENABLED: 3653 *valp = _ACL_ACE_ENABLED; 3654 return (0); 3655 3656 case _PC_MIN_HOLE_SIZE: 3657 *valp = (ulong_t)SPA_MINBLOCKSIZE; 3658 return (0); 3659 3660 default: 3661 return (fs_pathconf(vp, cmd, valp, cr)); 3662 } 3663 } 3664 3665 /*ARGSUSED*/ 3666 static int 3667 zfs_getsecattr(vnode_t *vp, vsecattr_t *vsecp, int flag, cred_t *cr) 3668 { 3669 znode_t *zp = VTOZ(vp); 3670 zfsvfs_t *zfsvfs = zp->z_zfsvfs; 3671 int error; 3672 3673 ZFS_ENTER_VERIFY_ZP(zfsvfs, zp); 3674 error = zfs_getacl(zp, vsecp, cr); 3675 ZFS_EXIT(zfsvfs); 3676 3677 return (error); 3678 } 3679 3680 /*ARGSUSED*/ 3681 static int 3682 zfs_setsecattr(vnode_t *vp, vsecattr_t *vsecp, int flag, cred_t *cr) 3683 { 3684 znode_t *zp = VTOZ(vp); 3685 zfsvfs_t *zfsvfs = zp->z_zfsvfs; 3686 int error; 3687 3688 ZFS_ENTER_VERIFY_ZP(zfsvfs, zp); 3689 error = zfs_setacl(zp, vsecp, cr); 3690 ZFS_EXIT(zfsvfs); 3691 return (error); 3692 } 3693 3694 /* 3695 * Predeclare these here so that the compiler assumes that 3696 * this is an "old style" function declaration that does 3697 * not include arguments => we won't get type mismatch errors 3698 * in the initializations that follow. 3699 */ 3700 static int zfs_inval(); 3701 static int zfs_isdir(); 3702 3703 static int 3704 zfs_inval() 3705 { 3706 return (EINVAL); 3707 } 3708 3709 static int 3710 zfs_isdir() 3711 { 3712 return (EISDIR); 3713 } 3714 /* 3715 * Directory vnode operations template 3716 */ 3717 vnodeops_t *zfs_dvnodeops; 3718 const fs_operation_def_t zfs_dvnodeops_template[] = { 3719 VOPNAME_OPEN, { .vop_open = zfs_open }, 3720 VOPNAME_CLOSE, { .vop_close = zfs_close }, 3721 VOPNAME_READ, { .error = zfs_isdir }, 3722 VOPNAME_WRITE, { .error = zfs_isdir }, 3723 VOPNAME_IOCTL, { .vop_ioctl = zfs_ioctl }, 3724 VOPNAME_GETATTR, { .vop_getattr = zfs_getattr }, 3725 VOPNAME_SETATTR, { .vop_setattr = zfs_setattr }, 3726 VOPNAME_ACCESS, { .vop_access = zfs_access }, 3727 VOPNAME_LOOKUP, { .vop_lookup = zfs_lookup }, 3728 VOPNAME_CREATE, { .vop_create = zfs_create }, 3729 VOPNAME_REMOVE, { .vop_remove = zfs_remove }, 3730 VOPNAME_LINK, { .vop_link = zfs_link }, 3731 VOPNAME_RENAME, { .vop_rename = zfs_rename }, 3732 VOPNAME_MKDIR, { .vop_mkdir = zfs_mkdir }, 3733 VOPNAME_RMDIR, { .vop_rmdir = zfs_rmdir }, 3734 VOPNAME_READDIR, { .vop_readdir = zfs_readdir }, 3735 VOPNAME_SYMLINK, { .vop_symlink = zfs_symlink }, 3736 VOPNAME_FSYNC, { .vop_fsync = zfs_fsync }, 3737 VOPNAME_INACTIVE, { .vop_inactive = zfs_inactive }, 3738 VOPNAME_FID, { .vop_fid = zfs_fid }, 3739 VOPNAME_SEEK, { .vop_seek = zfs_seek }, 3740 VOPNAME_PATHCONF, { .vop_pathconf = zfs_pathconf }, 3741 VOPNAME_GETSECATTR, { .vop_getsecattr = zfs_getsecattr }, 3742 VOPNAME_SETSECATTR, { .vop_setsecattr = zfs_setsecattr }, 3743 VOPNAME_VNEVENT, { .vop_vnevent = fs_vnevent_support }, 3744 NULL, NULL 3745 }; 3746 3747 /* 3748 * Regular file vnode operations template 3749 */ 3750 vnodeops_t *zfs_fvnodeops; 3751 const fs_operation_def_t zfs_fvnodeops_template[] = { 3752 VOPNAME_OPEN, { .vop_open = zfs_open }, 3753 VOPNAME_CLOSE, { .vop_close = zfs_close }, 3754 VOPNAME_READ, { .vop_read = zfs_read }, 3755 VOPNAME_WRITE, { .vop_write = zfs_write }, 3756 VOPNAME_IOCTL, { .vop_ioctl = zfs_ioctl }, 3757 VOPNAME_GETATTR, { .vop_getattr = zfs_getattr }, 3758 VOPNAME_SETATTR, { .vop_setattr = zfs_setattr }, 3759 VOPNAME_ACCESS, { .vop_access = zfs_access }, 3760 VOPNAME_LOOKUP, { .vop_lookup = zfs_lookup }, 3761 VOPNAME_RENAME, { .vop_rename = zfs_rename }, 3762 VOPNAME_FSYNC, { .vop_fsync = zfs_fsync }, 3763 VOPNAME_INACTIVE, { .vop_inactive = zfs_inactive }, 3764 VOPNAME_FID, { .vop_fid = zfs_fid }, 3765 VOPNAME_SEEK, { .vop_seek = zfs_seek }, 3766 VOPNAME_FRLOCK, { .vop_frlock = zfs_frlock }, 3767 VOPNAME_SPACE, { .vop_space = zfs_space }, 3768 VOPNAME_GETPAGE, { .vop_getpage = zfs_getpage }, 3769 VOPNAME_PUTPAGE, { .vop_putpage = zfs_putpage }, 3770 VOPNAME_MAP, { .vop_map = zfs_map }, 3771 VOPNAME_ADDMAP, { .vop_addmap = zfs_addmap }, 3772 VOPNAME_DELMAP, { .vop_delmap = zfs_delmap }, 3773 VOPNAME_PATHCONF, { .vop_pathconf = zfs_pathconf }, 3774 VOPNAME_GETSECATTR, { .vop_getsecattr = zfs_getsecattr }, 3775 VOPNAME_SETSECATTR, { .vop_setsecattr = zfs_setsecattr }, 3776 VOPNAME_VNEVENT, { .vop_vnevent = fs_vnevent_support }, 3777 NULL, NULL 3778 }; 3779 3780 /* 3781 * Symbolic link vnode operations template 3782 */ 3783 vnodeops_t *zfs_symvnodeops; 3784 const fs_operation_def_t zfs_symvnodeops_template[] = { 3785 VOPNAME_GETATTR, { .vop_getattr = zfs_getattr }, 3786 VOPNAME_SETATTR, { .vop_setattr = zfs_setattr }, 3787 VOPNAME_ACCESS, { .vop_access = zfs_access }, 3788 VOPNAME_RENAME, { .vop_rename = zfs_rename }, 3789 VOPNAME_READLINK, { .vop_readlink = zfs_readlink }, 3790 VOPNAME_INACTIVE, { .vop_inactive = zfs_inactive }, 3791 VOPNAME_FID, { .vop_fid = zfs_fid }, 3792 VOPNAME_PATHCONF, { .vop_pathconf = zfs_pathconf }, 3793 VOPNAME_VNEVENT, { .vop_vnevent = fs_vnevent_support }, 3794 NULL, NULL 3795 }; 3796 3797 /* 3798 * Extended attribute directory vnode operations template 3799 * This template is identical to the directory vnodes 3800 * operation template except for restricted operations: 3801 * VOP_MKDIR() 3802 * VOP_SYMLINK() 3803 * Note that there are other restrictions embedded in: 3804 * zfs_create() - restrict type to VREG 3805 * zfs_link() - no links into/out of attribute space 3806 * zfs_rename() - no moves into/out of attribute space 3807 */ 3808 vnodeops_t *zfs_xdvnodeops; 3809 const fs_operation_def_t zfs_xdvnodeops_template[] = { 3810 VOPNAME_OPEN, { .vop_open = zfs_open }, 3811 VOPNAME_CLOSE, { .vop_close = zfs_close }, 3812 VOPNAME_IOCTL, { .vop_ioctl = zfs_ioctl }, 3813 VOPNAME_GETATTR, { .vop_getattr = zfs_getattr }, 3814 VOPNAME_SETATTR, { .vop_setattr = zfs_setattr }, 3815 VOPNAME_ACCESS, { .vop_access = zfs_access }, 3816 VOPNAME_LOOKUP, { .vop_lookup = zfs_lookup }, 3817 VOPNAME_CREATE, { .vop_create = zfs_create }, 3818 VOPNAME_REMOVE, { .vop_remove = zfs_remove }, 3819 VOPNAME_LINK, { .vop_link = zfs_link }, 3820 VOPNAME_RENAME, { .vop_rename = zfs_rename }, 3821 VOPNAME_MKDIR, { .error = zfs_inval }, 3822 VOPNAME_RMDIR, { .vop_rmdir = zfs_rmdir }, 3823 VOPNAME_READDIR, { .vop_readdir = zfs_readdir }, 3824 VOPNAME_SYMLINK, { .error = zfs_inval }, 3825 VOPNAME_FSYNC, { .vop_fsync = zfs_fsync }, 3826 VOPNAME_INACTIVE, { .vop_inactive = zfs_inactive }, 3827 VOPNAME_FID, { .vop_fid = zfs_fid }, 3828 VOPNAME_SEEK, { .vop_seek = zfs_seek }, 3829 VOPNAME_PATHCONF, { .vop_pathconf = zfs_pathconf }, 3830 VOPNAME_GETSECATTR, { .vop_getsecattr = zfs_getsecattr }, 3831 VOPNAME_SETSECATTR, { .vop_setsecattr = zfs_setsecattr }, 3832 VOPNAME_VNEVENT, { .vop_vnevent = fs_vnevent_support }, 3833 NULL, NULL 3834 }; 3835 3836 /* 3837 * Error vnode operations template 3838 */ 3839 vnodeops_t *zfs_evnodeops; 3840 const fs_operation_def_t zfs_evnodeops_template[] = { 3841 VOPNAME_INACTIVE, { .vop_inactive = zfs_inactive }, 3842 VOPNAME_PATHCONF, { .vop_pathconf = zfs_pathconf }, 3843 NULL, NULL 3844 }; 3845