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). 87 * A ZFS_EXIT(zfsvfs) is needed before all returns. 88 * 89 * (2) VN_RELE() should always be the last thing except for zil_commit() 90 * (if necessary) and ZFS_EXIT(). This is for 3 reasons: 91 * First, if it's the last reference, the vnode/znode 92 * can be freed, so the zp may point to freed memory. Second, the last 93 * reference will call zfs_zinactive(), which may induce a lot of work -- 94 * pushing cached pages (which acquires range locks) and syncing out 95 * cached atime changes. Third, zfs_zinactive() may require a new tx, 96 * which could deadlock the system if you were already holding one. 97 * 98 * (3) All range locks must be grabbed before calling dmu_tx_assign(), 99 * as they can span dmu_tx_assign() calls. 100 * 101 * (4) Always pass zfsvfs->z_assign as the second argument to dmu_tx_assign(). 102 * In normal operation, this will be TXG_NOWAIT. During ZIL replay, 103 * it will be a specific txg. Either way, dmu_tx_assign() never blocks. 104 * This is critical because we don't want to block while holding locks. 105 * Note, in particular, that if a lock is sometimes acquired before 106 * the tx assigns, and sometimes after (e.g. z_lock), then failing to 107 * use a non-blocking assign can deadlock the system. The scenario: 108 * 109 * Thread A has grabbed a lock before calling dmu_tx_assign(). 110 * Thread B is in an already-assigned tx, and blocks for this lock. 111 * Thread A calls dmu_tx_assign(TXG_WAIT) and blocks in txg_wait_open() 112 * forever, because the previous txg can't quiesce until B's tx commits. 113 * 114 * If dmu_tx_assign() returns ERESTART and zfsvfs->z_assign is TXG_NOWAIT, 115 * then drop all locks, call dmu_tx_wait(), and try again. 116 * 117 * (5) If the operation succeeded, generate the intent log entry for it 118 * before dropping locks. This ensures that the ordering of events 119 * in the intent log matches the order in which they actually occurred. 120 * 121 * (6) At the end of each vnode op, the DMU tx must always commit, 122 * regardless of whether there were any errors. 123 * 124 * (7) After dropping all locks, invoke zil_commit(zilog, seq, foid) 125 * to ensure that synchronous semantics are provided when necessary. 126 * 127 * In general, this is how things should be ordered in each vnode op: 128 * 129 * ZFS_ENTER(zfsvfs); // exit if unmounted 130 * top: 131 * zfs_dirent_lock(&dl, ...) // lock directory entry (may VN_HOLD()) 132 * rw_enter(...); // grab any other locks you need 133 * tx = dmu_tx_create(...); // get DMU tx 134 * dmu_tx_hold_*(); // hold each object you might modify 135 * error = dmu_tx_assign(tx, zfsvfs->z_assign); // try to assign 136 * if (error) { 137 * rw_exit(...); // drop locks 138 * zfs_dirent_unlock(dl); // unlock directory entry 139 * VN_RELE(...); // release held vnodes 140 * if (error == ERESTART && zfsvfs->z_assign == TXG_NOWAIT) { 141 * dmu_tx_wait(tx); 142 * dmu_tx_abort(tx); 143 * goto top; 144 * } 145 * dmu_tx_abort(tx); // abort DMU tx 146 * ZFS_EXIT(zfsvfs); // finished in zfs 147 * return (error); // really out of space 148 * } 149 * error = do_real_work(); // do whatever this VOP does 150 * if (error == 0) 151 * zfs_log_*(...); // on success, make ZIL entry 152 * dmu_tx_commit(tx); // commit DMU tx -- error or not 153 * rw_exit(...); // drop locks 154 * zfs_dirent_unlock(dl); // unlock directory entry 155 * VN_RELE(...); // release held vnodes 156 * zil_commit(zilog, seq, foid); // synchronous when necessary 157 * ZFS_EXIT(zfsvfs); // finished in zfs 158 * return (error); // done, report error 159 */ 160 /* ARGSUSED */ 161 static int 162 zfs_open(vnode_t **vpp, int flag, cred_t *cr) 163 { 164 znode_t *zp = VTOZ(*vpp); 165 166 /* Keep a count of the synchronous opens in the znode */ 167 if (flag & (FSYNC | FDSYNC)) 168 atomic_inc_32(&zp->z_sync_cnt); 169 return (0); 170 } 171 172 /* ARGSUSED */ 173 static int 174 zfs_close(vnode_t *vp, int flag, int count, offset_t offset, cred_t *cr) 175 { 176 znode_t *zp = VTOZ(vp); 177 178 /* Decrement the synchronous opens in the znode */ 179 if ((flag & (FSYNC | FDSYNC)) && (count == 1)) 180 atomic_dec_32(&zp->z_sync_cnt); 181 182 /* 183 * Clean up any locks held by this process on the vp. 184 */ 185 cleanlocks(vp, ddi_get_pid(), 0); 186 cleanshares(vp, ddi_get_pid()); 187 188 return (0); 189 } 190 191 /* 192 * Lseek support for finding holes (cmd == _FIO_SEEK_HOLE) and 193 * data (cmd == _FIO_SEEK_DATA). "off" is an in/out parameter. 194 */ 195 static int 196 zfs_holey(vnode_t *vp, int cmd, offset_t *off) 197 { 198 znode_t *zp = VTOZ(vp); 199 uint64_t noff = (uint64_t)*off; /* new offset */ 200 uint64_t file_sz; 201 int error; 202 boolean_t hole; 203 204 file_sz = zp->z_phys->zp_size; 205 if (noff >= file_sz) { 206 return (ENXIO); 207 } 208 209 if (cmd == _FIO_SEEK_HOLE) 210 hole = B_TRUE; 211 else 212 hole = B_FALSE; 213 214 error = dmu_offset_next(zp->z_zfsvfs->z_os, zp->z_id, hole, &noff); 215 216 /* end of file? */ 217 if ((error == ESRCH) || (noff > file_sz)) { 218 /* 219 * Handle the virtual hole at the end of file. 220 */ 221 if (hole) { 222 *off = file_sz; 223 return (0); 224 } 225 return (ENXIO); 226 } 227 228 if (noff < *off) 229 return (error); 230 *off = noff; 231 return (error); 232 } 233 234 /* ARGSUSED */ 235 static int 236 zfs_ioctl(vnode_t *vp, int com, intptr_t data, int flag, cred_t *cred, 237 int *rvalp) 238 { 239 offset_t off; 240 int error; 241 zfsvfs_t *zfsvfs; 242 243 switch (com) { 244 case _FIOFFS: 245 return (zfs_sync(vp->v_vfsp, 0, cred)); 246 247 /* 248 * The following two ioctls are used by bfu. Faking out, 249 * necessary to avoid bfu errors. 250 */ 251 case _FIOGDIO: 252 case _FIOSDIO: 253 return (0); 254 255 case _FIO_SEEK_DATA: 256 case _FIO_SEEK_HOLE: 257 if (ddi_copyin((void *)data, &off, sizeof (off), flag)) 258 return (EFAULT); 259 260 zfsvfs = VTOZ(vp)->z_zfsvfs; 261 ZFS_ENTER(zfsvfs); 262 263 /* offset parameter is in/out */ 264 error = zfs_holey(vp, com, &off); 265 ZFS_EXIT(zfsvfs); 266 if (error) 267 return (error); 268 if (ddi_copyout(&off, (void *)data, sizeof (off), flag)) 269 return (EFAULT); 270 return (0); 271 } 272 return (ENOTTY); 273 } 274 275 /* 276 * When a file is memory mapped, we must keep the IO data synchronized 277 * between the DMU cache and the memory mapped pages. What this means: 278 * 279 * On Write: If we find a memory mapped page, we write to *both* 280 * the page and the dmu buffer. 281 * 282 * NOTE: We will always "break up" the IO into PAGESIZE uiomoves when 283 * the file is memory mapped. 284 */ 285 static int 286 mappedwrite(vnode_t *vp, int nbytes, uio_t *uio, dmu_tx_t *tx) 287 { 288 znode_t *zp = VTOZ(vp); 289 zfsvfs_t *zfsvfs = zp->z_zfsvfs; 290 int64_t start, off; 291 int len = nbytes; 292 int error = 0; 293 294 start = uio->uio_loffset; 295 off = start & PAGEOFFSET; 296 for (start &= PAGEMASK; len > 0; start += PAGESIZE) { 297 page_t *pp; 298 uint64_t bytes = MIN(PAGESIZE - off, len); 299 uint64_t woff = uio->uio_loffset; 300 301 /* 302 * We don't want a new page to "appear" in the middle of 303 * the file update (because it may not get the write 304 * update data), so we grab a lock to block 305 * zfs_getpage(). 306 */ 307 rw_enter(&zp->z_map_lock, RW_WRITER); 308 if (pp = page_lookup(vp, start, SE_SHARED)) { 309 caddr_t va; 310 311 rw_exit(&zp->z_map_lock); 312 va = ppmapin(pp, PROT_READ | PROT_WRITE, (caddr_t)-1L); 313 error = uiomove(va+off, bytes, UIO_WRITE, uio); 314 if (error == 0) { 315 dmu_write(zfsvfs->z_os, zp->z_id, 316 woff, bytes, va+off, tx); 317 } 318 ppmapout(va); 319 page_unlock(pp); 320 } else { 321 error = dmu_write_uio(zfsvfs->z_os, zp->z_id, 322 uio, bytes, tx); 323 rw_exit(&zp->z_map_lock); 324 } 325 len -= bytes; 326 off = 0; 327 if (error) 328 break; 329 } 330 return (error); 331 } 332 333 /* 334 * When a file is memory mapped, we must keep the IO data synchronized 335 * between the DMU cache and the memory mapped pages. What this means: 336 * 337 * On Read: We "read" preferentially from memory mapped pages, 338 * else we default from the dmu buffer. 339 * 340 * NOTE: We will always "break up" the IO into PAGESIZE uiomoves when 341 * the file is memory mapped. 342 */ 343 static int 344 mappedread(vnode_t *vp, int nbytes, uio_t *uio) 345 { 346 znode_t *zp = VTOZ(vp); 347 objset_t *os = zp->z_zfsvfs->z_os; 348 int64_t start, off; 349 int len = nbytes; 350 int error = 0; 351 352 start = uio->uio_loffset; 353 off = start & PAGEOFFSET; 354 for (start &= PAGEMASK; len > 0; start += PAGESIZE) { 355 page_t *pp; 356 uint64_t bytes = MIN(PAGESIZE - off, len); 357 358 if (pp = page_lookup(vp, start, SE_SHARED)) { 359 caddr_t va; 360 361 va = ppmapin(pp, PROT_READ, (caddr_t)-1L); 362 error = uiomove(va + off, bytes, UIO_READ, uio); 363 ppmapout(va); 364 page_unlock(pp); 365 } else { 366 error = dmu_read_uio(os, zp->z_id, uio, bytes); 367 } 368 len -= bytes; 369 off = 0; 370 if (error) 371 break; 372 } 373 return (error); 374 } 375 376 offset_t zfs_read_chunk_size = 1024 * 1024; /* Tunable */ 377 378 /* 379 * Read bytes from specified file into supplied buffer. 380 * 381 * IN: vp - vnode of file to be read from. 382 * uio - structure supplying read location, range info, 383 * and return buffer. 384 * ioflag - SYNC flags; used to provide FRSYNC semantics. 385 * cr - credentials of caller. 386 * 387 * OUT: uio - updated offset and range, buffer filled. 388 * 389 * RETURN: 0 if success 390 * error code if failure 391 * 392 * Side Effects: 393 * vp - atime updated if byte count > 0 394 */ 395 /* ARGSUSED */ 396 static int 397 zfs_read(vnode_t *vp, uio_t *uio, int ioflag, cred_t *cr, caller_context_t *ct) 398 { 399 znode_t *zp = VTOZ(vp); 400 zfsvfs_t *zfsvfs = zp->z_zfsvfs; 401 objset_t *os = zfsvfs->z_os; 402 ssize_t n, nbytes; 403 int error; 404 rl_t *rl; 405 406 ZFS_ENTER(zfsvfs); 407 408 /* 409 * Validate file offset 410 */ 411 if (uio->uio_loffset < (offset_t)0) { 412 ZFS_EXIT(zfsvfs); 413 return (EINVAL); 414 } 415 416 /* 417 * Fasttrack empty reads 418 */ 419 if (uio->uio_resid == 0) { 420 ZFS_EXIT(zfsvfs); 421 return (0); 422 } 423 424 /* 425 * Check for mandatory locks 426 */ 427 if (MANDMODE((mode_t)zp->z_phys->zp_mode)) { 428 if (error = chklock(vp, FREAD, 429 uio->uio_loffset, uio->uio_resid, uio->uio_fmode, ct)) { 430 ZFS_EXIT(zfsvfs); 431 return (error); 432 } 433 } 434 435 /* 436 * If we're in FRSYNC mode, sync out this znode before reading it. 437 */ 438 if (ioflag & FRSYNC) 439 zil_commit(zfsvfs->z_log, zp->z_last_itx, zp->z_id); 440 441 /* 442 * Lock the range against changes. 443 */ 444 rl = zfs_range_lock(zp, uio->uio_loffset, uio->uio_resid, RL_READER); 445 446 /* 447 * If we are reading past end-of-file we can skip 448 * to the end; but we might still need to set atime. 449 */ 450 if (uio->uio_loffset >= zp->z_phys->zp_size) { 451 error = 0; 452 goto out; 453 } 454 455 ASSERT(uio->uio_loffset < zp->z_phys->zp_size); 456 n = MIN(uio->uio_resid, zp->z_phys->zp_size - uio->uio_loffset); 457 458 while (n > 0) { 459 nbytes = MIN(n, zfs_read_chunk_size - 460 P2PHASE(uio->uio_loffset, zfs_read_chunk_size)); 461 462 if (vn_has_cached_data(vp)) 463 error = mappedread(vp, nbytes, uio); 464 else 465 error = dmu_read_uio(os, zp->z_id, uio, nbytes); 466 if (error) 467 break; 468 469 n -= nbytes; 470 } 471 472 out: 473 zfs_range_unlock(rl); 474 475 ZFS_ACCESSTIME_STAMP(zfsvfs, zp); 476 ZFS_EXIT(zfsvfs); 477 return (error); 478 } 479 480 /* 481 * Fault in the pages of the first n bytes specified by the uio structure. 482 * 1 byte in each page is touched and the uio struct is unmodified. 483 * Any error will exit this routine as this is only a best 484 * attempt to get the pages resident. This is a copy of ufs_trans_touch(). 485 */ 486 static void 487 zfs_prefault_write(ssize_t n, struct uio *uio) 488 { 489 struct iovec *iov; 490 ulong_t cnt, incr; 491 caddr_t p; 492 uint8_t tmp; 493 494 iov = uio->uio_iov; 495 496 while (n) { 497 cnt = MIN(iov->iov_len, n); 498 if (cnt == 0) { 499 /* empty iov entry */ 500 iov++; 501 continue; 502 } 503 n -= cnt; 504 /* 505 * touch each page in this segment. 506 */ 507 p = iov->iov_base; 508 while (cnt) { 509 switch (uio->uio_segflg) { 510 case UIO_USERSPACE: 511 case UIO_USERISPACE: 512 if (fuword8(p, &tmp)) 513 return; 514 break; 515 case UIO_SYSSPACE: 516 if (kcopy(p, &tmp, 1)) 517 return; 518 break; 519 } 520 incr = MIN(cnt, PAGESIZE); 521 p += incr; 522 cnt -= incr; 523 } 524 /* 525 * touch the last byte in case it straddles a page. 526 */ 527 p--; 528 switch (uio->uio_segflg) { 529 case UIO_USERSPACE: 530 case UIO_USERISPACE: 531 if (fuword8(p, &tmp)) 532 return; 533 break; 534 case UIO_SYSSPACE: 535 if (kcopy(p, &tmp, 1)) 536 return; 537 break; 538 } 539 iov++; 540 } 541 } 542 543 /* 544 * Write the bytes to a file. 545 * 546 * IN: vp - vnode of file to be written to. 547 * uio - structure supplying write location, range info, 548 * and data buffer. 549 * ioflag - FAPPEND flag set if in append mode. 550 * cr - credentials of caller. 551 * 552 * OUT: uio - updated offset and range. 553 * 554 * RETURN: 0 if success 555 * error code if failure 556 * 557 * Timestamps: 558 * vp - ctime|mtime updated if byte count > 0 559 */ 560 /* ARGSUSED */ 561 static int 562 zfs_write(vnode_t *vp, uio_t *uio, int ioflag, cred_t *cr, caller_context_t *ct) 563 { 564 znode_t *zp = VTOZ(vp); 565 rlim64_t limit = uio->uio_llimit; 566 ssize_t start_resid = uio->uio_resid; 567 ssize_t tx_bytes; 568 uint64_t end_size; 569 dmu_tx_t *tx; 570 zfsvfs_t *zfsvfs = zp->z_zfsvfs; 571 zilog_t *zilog = zfsvfs->z_log; 572 offset_t woff; 573 ssize_t n, nbytes; 574 rl_t *rl; 575 int max_blksz = zfsvfs->z_max_blksz; 576 int error; 577 578 /* 579 * Fasttrack empty write 580 */ 581 n = start_resid; 582 if (n == 0) 583 return (0); 584 585 if (limit == RLIM64_INFINITY || limit > MAXOFFSET_T) 586 limit = MAXOFFSET_T; 587 588 ZFS_ENTER(zfsvfs); 589 590 /* 591 * Pre-fault the pages to ensure slow (eg NFS) pages 592 * don't hold up txg. 593 */ 594 zfs_prefault_write(n, uio); 595 596 /* 597 * If in append mode, set the io offset pointer to eof. 598 */ 599 if (ioflag & FAPPEND) { 600 /* 601 * Range lock for a file append: 602 * The value for the start of range will be determined by 603 * zfs_range_lock() (to guarantee append semantics). 604 * If this write will cause the block size to increase, 605 * zfs_range_lock() will lock the entire file, so we must 606 * later reduce the range after we grow the block size. 607 */ 608 rl = zfs_range_lock(zp, 0, n, RL_APPEND); 609 if (rl->r_len == UINT64_MAX) { 610 /* overlocked, zp_size can't change */ 611 woff = uio->uio_loffset = zp->z_phys->zp_size; 612 } else { 613 woff = uio->uio_loffset = rl->r_off; 614 } 615 } else { 616 woff = uio->uio_loffset; 617 /* 618 * Validate file offset 619 */ 620 if (woff < 0) { 621 ZFS_EXIT(zfsvfs); 622 return (EINVAL); 623 } 624 625 /* 626 * If we need to grow the block size then zfs_range_lock() 627 * will lock a wider range than we request here. 628 * Later after growing the block size we reduce the range. 629 */ 630 rl = zfs_range_lock(zp, woff, n, RL_WRITER); 631 } 632 633 if (woff >= limit) { 634 zfs_range_unlock(rl); 635 ZFS_EXIT(zfsvfs); 636 return (EFBIG); 637 } 638 639 if ((woff + n) > limit || woff > (limit - n)) 640 n = limit - woff; 641 642 /* 643 * Check for mandatory locks 644 */ 645 if (MANDMODE((mode_t)zp->z_phys->zp_mode) && 646 (error = chklock(vp, FWRITE, woff, n, uio->uio_fmode, ct)) != 0) { 647 zfs_range_unlock(rl); 648 ZFS_EXIT(zfsvfs); 649 return (error); 650 } 651 end_size = MAX(zp->z_phys->zp_size, woff + n); 652 653 /* 654 * Write the file in reasonable size chunks. Each chunk is written 655 * in a separate transaction; this keeps the intent log records small 656 * and allows us to do more fine-grained space accounting. 657 */ 658 while (n > 0) { 659 /* 660 * Start a transaction. 661 */ 662 woff = uio->uio_loffset; 663 tx = dmu_tx_create(zfsvfs->z_os); 664 dmu_tx_hold_bonus(tx, zp->z_id); 665 dmu_tx_hold_write(tx, zp->z_id, woff, MIN(n, max_blksz)); 666 error = dmu_tx_assign(tx, zfsvfs->z_assign); 667 if (error) { 668 if (error == ERESTART && 669 zfsvfs->z_assign == TXG_NOWAIT) { 670 dmu_tx_wait(tx); 671 dmu_tx_abort(tx); 672 continue; 673 } 674 dmu_tx_abort(tx); 675 break; 676 } 677 678 /* 679 * If zfs_range_lock() over-locked we grow the blocksize 680 * and then reduce the lock range. This will only happen 681 * on the first iteration since zfs_range_reduce() will 682 * shrink down r_len to the appropriate size. 683 */ 684 if (rl->r_len == UINT64_MAX) { 685 uint64_t new_blksz; 686 687 if (zp->z_blksz > max_blksz) { 688 ASSERT(!ISP2(zp->z_blksz)); 689 new_blksz = MIN(end_size, SPA_MAXBLOCKSIZE); 690 } else { 691 new_blksz = MIN(end_size, max_blksz); 692 } 693 zfs_grow_blocksize(zp, new_blksz, tx); 694 zfs_range_reduce(rl, woff, n); 695 } 696 697 /* 698 * XXX - should we really limit each write to z_max_blksz? 699 * Perhaps we should use SPA_MAXBLOCKSIZE chunks? 700 */ 701 nbytes = MIN(n, max_blksz - P2PHASE(woff, max_blksz)); 702 rw_enter(&zp->z_map_lock, RW_READER); 703 704 tx_bytes = uio->uio_resid; 705 if (vn_has_cached_data(vp)) { 706 rw_exit(&zp->z_map_lock); 707 error = mappedwrite(vp, nbytes, uio, tx); 708 } else { 709 error = dmu_write_uio(zfsvfs->z_os, zp->z_id, 710 uio, nbytes, tx); 711 rw_exit(&zp->z_map_lock); 712 } 713 tx_bytes -= uio->uio_resid; 714 715 /* 716 * If we made no progress, we're done. If we made even 717 * partial progress, update the znode and ZIL accordingly. 718 */ 719 if (tx_bytes == 0) { 720 dmu_tx_commit(tx); 721 ASSERT(error != 0); 722 break; 723 } 724 725 /* 726 * Clear Set-UID/Set-GID bits on successful write if not 727 * privileged and at least one of the excute bits is set. 728 * 729 * It would be nice to to this after all writes have 730 * been done, but that would still expose the ISUID/ISGID 731 * to another app after the partial write is committed. 732 */ 733 mutex_enter(&zp->z_acl_lock); 734 if ((zp->z_phys->zp_mode & (S_IXUSR | (S_IXUSR >> 3) | 735 (S_IXUSR >> 6))) != 0 && 736 (zp->z_phys->zp_mode & (S_ISUID | S_ISGID)) != 0 && 737 secpolicy_vnode_setid_retain(cr, 738 (zp->z_phys->zp_mode & S_ISUID) != 0 && 739 zp->z_phys->zp_uid == 0) != 0) { 740 zp->z_phys->zp_mode &= ~(S_ISUID | S_ISGID); 741 } 742 mutex_exit(&zp->z_acl_lock); 743 744 /* 745 * Update time stamp. NOTE: This marks the bonus buffer as 746 * dirty, so we don't have to do it again for zp_size. 747 */ 748 zfs_time_stamper(zp, CONTENT_MODIFIED, tx); 749 750 /* 751 * Update the file size (zp_size) if it has changed; 752 * account for possible concurrent updates. 753 */ 754 while ((end_size = zp->z_phys->zp_size) < uio->uio_loffset) 755 (void) atomic_cas_64(&zp->z_phys->zp_size, end_size, 756 uio->uio_loffset); 757 zfs_log_write(zilog, tx, TX_WRITE, zp, woff, tx_bytes, ioflag); 758 dmu_tx_commit(tx); 759 760 if (error != 0) 761 break; 762 ASSERT(tx_bytes == nbytes); 763 n -= nbytes; 764 } 765 766 zfs_range_unlock(rl); 767 768 /* 769 * If we're in replay mode, or we made no progress, return error. 770 * Otherwise, it's at least a partial write, so it's successful. 771 */ 772 if (zfsvfs->z_assign >= TXG_INITIAL || uio->uio_resid == start_resid) { 773 ZFS_EXIT(zfsvfs); 774 return (error); 775 } 776 777 if (ioflag & (FSYNC | FDSYNC)) 778 zil_commit(zilog, zp->z_last_itx, zp->z_id); 779 780 ZFS_EXIT(zfsvfs); 781 return (0); 782 } 783 784 void 785 zfs_get_done(dmu_buf_t *db, void *vzgd) 786 { 787 zgd_t *zgd = (zgd_t *)vzgd; 788 rl_t *rl = zgd->zgd_rl; 789 vnode_t *vp = ZTOV(rl->r_zp); 790 791 dmu_buf_rele(db, vzgd); 792 zfs_range_unlock(rl); 793 VN_RELE(vp); 794 zil_add_vdev(zgd->zgd_zilog, DVA_GET_VDEV(BP_IDENTITY(zgd->zgd_bp))); 795 kmem_free(zgd, sizeof (zgd_t)); 796 } 797 798 /* 799 * Get data to generate a TX_WRITE intent log record. 800 */ 801 int 802 zfs_get_data(void *arg, lr_write_t *lr, char *buf, zio_t *zio) 803 { 804 zfsvfs_t *zfsvfs = arg; 805 objset_t *os = zfsvfs->z_os; 806 znode_t *zp; 807 uint64_t off = lr->lr_offset; 808 dmu_buf_t *db; 809 rl_t *rl; 810 zgd_t *zgd; 811 int dlen = lr->lr_length; /* length of user data */ 812 int error = 0; 813 814 ASSERT(zio); 815 ASSERT(dlen != 0); 816 817 /* 818 * Nothing to do if the file has been removed 819 */ 820 if (zfs_zget(zfsvfs, lr->lr_foid, &zp) != 0) 821 return (ENOENT); 822 if (zp->z_unlinked) { 823 VN_RELE(ZTOV(zp)); 824 return (ENOENT); 825 } 826 827 /* 828 * Write records come in two flavors: immediate and indirect. 829 * For small writes it's cheaper to store the data with the 830 * log record (immediate); for large writes it's cheaper to 831 * sync the data and get a pointer to it (indirect) so that 832 * we don't have to write the data twice. 833 */ 834 if (buf != NULL) { /* immediate write */ 835 rl = zfs_range_lock(zp, off, dlen, RL_READER); 836 /* test for truncation needs to be done while range locked */ 837 if (off >= zp->z_phys->zp_size) { 838 error = ENOENT; 839 goto out; 840 } 841 VERIFY(0 == dmu_read(os, lr->lr_foid, off, dlen, buf)); 842 } else { /* indirect write */ 843 uint64_t boff; /* block starting offset */ 844 845 /* 846 * Have to lock the whole block to ensure when it's 847 * written out and it's checksum is being calculated 848 * that no one can change the data. We need to re-check 849 * blocksize after we get the lock in case it's changed! 850 */ 851 for (;;) { 852 if (ISP2(zp->z_blksz)) { 853 boff = P2ALIGN_TYPED(off, zp->z_blksz, 854 uint64_t); 855 } else { 856 boff = 0; 857 } 858 dlen = zp->z_blksz; 859 rl = zfs_range_lock(zp, boff, dlen, RL_READER); 860 if (zp->z_blksz == dlen) 861 break; 862 zfs_range_unlock(rl); 863 } 864 /* test for truncation needs to be done while range locked */ 865 if (off >= zp->z_phys->zp_size) { 866 error = ENOENT; 867 goto out; 868 } 869 zgd = (zgd_t *)kmem_alloc(sizeof (zgd_t), KM_SLEEP); 870 zgd->zgd_rl = rl; 871 zgd->zgd_zilog = zfsvfs->z_log; 872 zgd->zgd_bp = &lr->lr_blkptr; 873 VERIFY(0 == dmu_buf_hold(os, lr->lr_foid, boff, zgd, &db)); 874 ASSERT(boff == db->db_offset); 875 lr->lr_blkoff = off - boff; 876 error = dmu_sync(zio, db, &lr->lr_blkptr, 877 lr->lr_common.lrc_txg, zfs_get_done, zgd); 878 ASSERT((error && error != EINPROGRESS) || 879 lr->lr_length <= zp->z_blksz); 880 if (error == 0) { 881 zil_add_vdev(zfsvfs->z_log, 882 DVA_GET_VDEV(BP_IDENTITY(&lr->lr_blkptr))); 883 } 884 /* 885 * If we get EINPROGRESS, then we need to wait for a 886 * write IO initiated by dmu_sync() to complete before 887 * we can release this dbuf. We will finish everything 888 * up in the zfs_get_done() callback. 889 */ 890 if (error == EINPROGRESS) 891 return (0); 892 dmu_buf_rele(db, zgd); 893 kmem_free(zgd, sizeof (zgd_t)); 894 } 895 out: 896 zfs_range_unlock(rl); 897 VN_RELE(ZTOV(zp)); 898 return (error); 899 } 900 901 /*ARGSUSED*/ 902 static int 903 zfs_access(vnode_t *vp, int mode, int flags, cred_t *cr) 904 { 905 znode_t *zp = VTOZ(vp); 906 zfsvfs_t *zfsvfs = zp->z_zfsvfs; 907 int error; 908 909 ZFS_ENTER(zfsvfs); 910 error = zfs_zaccess_rwx(zp, mode, cr); 911 ZFS_EXIT(zfsvfs); 912 return (error); 913 } 914 915 /* 916 * Lookup an entry in a directory, or an extended attribute directory. 917 * If it exists, return a held vnode reference for it. 918 * 919 * IN: dvp - vnode of directory to search. 920 * nm - name of entry to lookup. 921 * pnp - full pathname to lookup [UNUSED]. 922 * flags - LOOKUP_XATTR set if looking for an attribute. 923 * rdir - root directory vnode [UNUSED]. 924 * cr - credentials of caller. 925 * 926 * OUT: vpp - vnode of located entry, NULL if not found. 927 * 928 * RETURN: 0 if success 929 * error code if failure 930 * 931 * Timestamps: 932 * NA 933 */ 934 /* ARGSUSED */ 935 static int 936 zfs_lookup(vnode_t *dvp, char *nm, vnode_t **vpp, struct pathname *pnp, 937 int flags, vnode_t *rdir, cred_t *cr) 938 { 939 940 znode_t *zdp = VTOZ(dvp); 941 zfsvfs_t *zfsvfs = zdp->z_zfsvfs; 942 int error; 943 944 ZFS_ENTER(zfsvfs); 945 946 *vpp = NULL; 947 948 if (flags & LOOKUP_XATTR) { 949 /* 950 * If the xattr property is off, refuse the lookup request. 951 */ 952 if (!(zfsvfs->z_vfs->vfs_flag & VFS_XATTR)) { 953 ZFS_EXIT(zfsvfs); 954 return (EINVAL); 955 } 956 957 /* 958 * We don't allow recursive attributes.. 959 * Maybe someday we will. 960 */ 961 if (zdp->z_phys->zp_flags & ZFS_XATTR) { 962 ZFS_EXIT(zfsvfs); 963 return (EINVAL); 964 } 965 966 if (error = zfs_get_xattrdir(VTOZ(dvp), vpp, cr, flags)) { 967 ZFS_EXIT(zfsvfs); 968 return (error); 969 } 970 971 /* 972 * Do we have permission to get into attribute directory? 973 */ 974 975 if (error = zfs_zaccess(VTOZ(*vpp), ACE_EXECUTE, cr)) { 976 VN_RELE(*vpp); 977 } 978 979 ZFS_EXIT(zfsvfs); 980 return (error); 981 } 982 983 if (dvp->v_type != VDIR) { 984 ZFS_EXIT(zfsvfs); 985 return (ENOTDIR); 986 } 987 988 /* 989 * Check accessibility of directory. 990 */ 991 992 if (error = zfs_zaccess(zdp, ACE_EXECUTE, cr)) { 993 ZFS_EXIT(zfsvfs); 994 return (error); 995 } 996 997 if ((error = zfs_dirlook(zdp, nm, vpp)) == 0) { 998 999 /* 1000 * Convert device special files 1001 */ 1002 if (IS_DEVVP(*vpp)) { 1003 vnode_t *svp; 1004 1005 svp = specvp(*vpp, (*vpp)->v_rdev, (*vpp)->v_type, cr); 1006 VN_RELE(*vpp); 1007 if (svp == NULL) 1008 error = ENOSYS; 1009 else 1010 *vpp = svp; 1011 } 1012 } 1013 1014 ZFS_EXIT(zfsvfs); 1015 return (error); 1016 } 1017 1018 /* 1019 * Attempt to create a new entry in a directory. If the entry 1020 * already exists, truncate the file if permissible, else return 1021 * an error. Return the vp of the created or trunc'd file. 1022 * 1023 * IN: dvp - vnode of directory to put new file entry in. 1024 * name - name of new file entry. 1025 * vap - attributes of new file. 1026 * excl - flag indicating exclusive or non-exclusive mode. 1027 * mode - mode to open file with. 1028 * cr - credentials of caller. 1029 * flag - large file flag [UNUSED]. 1030 * 1031 * OUT: vpp - vnode of created or trunc'd entry. 1032 * 1033 * RETURN: 0 if success 1034 * error code if failure 1035 * 1036 * Timestamps: 1037 * dvp - ctime|mtime updated if new entry created 1038 * vp - ctime|mtime always, atime if new 1039 */ 1040 /* ARGSUSED */ 1041 static int 1042 zfs_create(vnode_t *dvp, char *name, vattr_t *vap, vcexcl_t excl, 1043 int mode, vnode_t **vpp, cred_t *cr, int flag) 1044 { 1045 znode_t *zp, *dzp = VTOZ(dvp); 1046 zfsvfs_t *zfsvfs = dzp->z_zfsvfs; 1047 zilog_t *zilog = zfsvfs->z_log; 1048 objset_t *os = zfsvfs->z_os; 1049 zfs_dirlock_t *dl; 1050 dmu_tx_t *tx; 1051 int error; 1052 uint64_t zoid; 1053 1054 ZFS_ENTER(zfsvfs); 1055 1056 top: 1057 *vpp = NULL; 1058 1059 if ((vap->va_mode & VSVTX) && secpolicy_vnode_stky_modify(cr)) 1060 vap->va_mode &= ~VSVTX; 1061 1062 if (*name == '\0') { 1063 /* 1064 * Null component name refers to the directory itself. 1065 */ 1066 VN_HOLD(dvp); 1067 zp = dzp; 1068 dl = NULL; 1069 error = 0; 1070 } else { 1071 /* possible VN_HOLD(zp) */ 1072 if (error = zfs_dirent_lock(&dl, dzp, name, &zp, 0)) { 1073 if (strcmp(name, "..") == 0) 1074 error = EISDIR; 1075 ZFS_EXIT(zfsvfs); 1076 return (error); 1077 } 1078 } 1079 1080 zoid = zp ? zp->z_id : -1ULL; 1081 1082 if (zp == NULL) { 1083 /* 1084 * Create a new file object and update the directory 1085 * to reference it. 1086 */ 1087 if (error = zfs_zaccess(dzp, ACE_ADD_FILE, cr)) { 1088 goto out; 1089 } 1090 1091 /* 1092 * We only support the creation of regular files in 1093 * extended attribute directories. 1094 */ 1095 if ((dzp->z_phys->zp_flags & ZFS_XATTR) && 1096 (vap->va_type != VREG)) { 1097 error = EINVAL; 1098 goto out; 1099 } 1100 1101 tx = dmu_tx_create(os); 1102 dmu_tx_hold_bonus(tx, DMU_NEW_OBJECT); 1103 dmu_tx_hold_bonus(tx, dzp->z_id); 1104 dmu_tx_hold_zap(tx, dzp->z_id, TRUE, name); 1105 if (dzp->z_phys->zp_flags & ZFS_INHERIT_ACE) 1106 dmu_tx_hold_write(tx, DMU_NEW_OBJECT, 1107 0, SPA_MAXBLOCKSIZE); 1108 error = dmu_tx_assign(tx, zfsvfs->z_assign); 1109 if (error) { 1110 zfs_dirent_unlock(dl); 1111 if (error == ERESTART && 1112 zfsvfs->z_assign == TXG_NOWAIT) { 1113 dmu_tx_wait(tx); 1114 dmu_tx_abort(tx); 1115 goto top; 1116 } 1117 dmu_tx_abort(tx); 1118 ZFS_EXIT(zfsvfs); 1119 return (error); 1120 } 1121 zfs_mknode(dzp, vap, &zoid, tx, cr, 0, &zp, 0); 1122 ASSERT(zp->z_id == zoid); 1123 (void) zfs_link_create(dl, zp, tx, ZNEW); 1124 zfs_log_create(zilog, tx, TX_CREATE, dzp, zp, name); 1125 dmu_tx_commit(tx); 1126 } else { 1127 /* 1128 * A directory entry already exists for this name. 1129 */ 1130 /* 1131 * Can't truncate an existing file if in exclusive mode. 1132 */ 1133 if (excl == EXCL) { 1134 error = EEXIST; 1135 goto out; 1136 } 1137 /* 1138 * Can't open a directory for writing. 1139 */ 1140 if ((ZTOV(zp)->v_type == VDIR) && (mode & S_IWRITE)) { 1141 error = EISDIR; 1142 goto out; 1143 } 1144 /* 1145 * Verify requested access to file. 1146 */ 1147 if (mode && (error = zfs_zaccess_rwx(zp, mode, cr))) { 1148 goto out; 1149 } 1150 1151 mutex_enter(&dzp->z_lock); 1152 dzp->z_seq++; 1153 mutex_exit(&dzp->z_lock); 1154 1155 /* 1156 * Truncate regular files if requested. 1157 */ 1158 if ((ZTOV(zp)->v_type == VREG) && 1159 (vap->va_mask & AT_SIZE) && (vap->va_size == 0)) { 1160 error = zfs_freesp(zp, 0, 0, mode, TRUE); 1161 if (error == ERESTART && 1162 zfsvfs->z_assign == TXG_NOWAIT) { 1163 /* NB: we already did dmu_tx_wait() */ 1164 zfs_dirent_unlock(dl); 1165 VN_RELE(ZTOV(zp)); 1166 goto top; 1167 } 1168 } 1169 } 1170 out: 1171 1172 if (dl) 1173 zfs_dirent_unlock(dl); 1174 1175 if (error) { 1176 if (zp) 1177 VN_RELE(ZTOV(zp)); 1178 } else { 1179 *vpp = ZTOV(zp); 1180 /* 1181 * If vnode is for a device return a specfs vnode instead. 1182 */ 1183 if (IS_DEVVP(*vpp)) { 1184 struct vnode *svp; 1185 1186 svp = specvp(*vpp, (*vpp)->v_rdev, (*vpp)->v_type, cr); 1187 VN_RELE(*vpp); 1188 if (svp == NULL) { 1189 error = ENOSYS; 1190 } 1191 *vpp = svp; 1192 } 1193 } 1194 1195 ZFS_EXIT(zfsvfs); 1196 return (error); 1197 } 1198 1199 /* 1200 * Remove an entry from a directory. 1201 * 1202 * IN: dvp - vnode of directory to remove entry from. 1203 * name - name of entry to remove. 1204 * cr - credentials of caller. 1205 * 1206 * RETURN: 0 if success 1207 * error code if failure 1208 * 1209 * Timestamps: 1210 * dvp - ctime|mtime 1211 * vp - ctime (if nlink > 0) 1212 */ 1213 static int 1214 zfs_remove(vnode_t *dvp, char *name, cred_t *cr) 1215 { 1216 znode_t *zp, *dzp = VTOZ(dvp); 1217 znode_t *xzp = NULL; 1218 vnode_t *vp; 1219 zfsvfs_t *zfsvfs = dzp->z_zfsvfs; 1220 zilog_t *zilog = zfsvfs->z_log; 1221 uint64_t acl_obj, xattr_obj; 1222 zfs_dirlock_t *dl; 1223 dmu_tx_t *tx; 1224 boolean_t may_delete_now, delete_now = FALSE; 1225 boolean_t unlinked; 1226 int error; 1227 1228 ZFS_ENTER(zfsvfs); 1229 1230 top: 1231 /* 1232 * Attempt to lock directory; fail if entry doesn't exist. 1233 */ 1234 if (error = zfs_dirent_lock(&dl, dzp, name, &zp, ZEXISTS)) { 1235 ZFS_EXIT(zfsvfs); 1236 return (error); 1237 } 1238 1239 vp = ZTOV(zp); 1240 1241 if (error = zfs_zaccess_delete(dzp, zp, cr)) { 1242 goto out; 1243 } 1244 1245 /* 1246 * Need to use rmdir for removing directories. 1247 */ 1248 if (vp->v_type == VDIR) { 1249 error = EPERM; 1250 goto out; 1251 } 1252 1253 vnevent_remove(vp); 1254 1255 dnlc_remove(dvp, name); 1256 1257 mutex_enter(&vp->v_lock); 1258 may_delete_now = vp->v_count == 1 && !vn_has_cached_data(vp); 1259 mutex_exit(&vp->v_lock); 1260 1261 /* 1262 * We may delete the znode now, or we may put it in the unlinked set; 1263 * it depends on whether we're the last link, and on whether there are 1264 * other holds on the vnode. So we dmu_tx_hold() the right things to 1265 * allow for either case. 1266 */ 1267 tx = dmu_tx_create(zfsvfs->z_os); 1268 dmu_tx_hold_zap(tx, dzp->z_id, FALSE, name); 1269 dmu_tx_hold_bonus(tx, zp->z_id); 1270 if (may_delete_now) 1271 dmu_tx_hold_free(tx, zp->z_id, 0, DMU_OBJECT_END); 1272 1273 /* are there any extended attributes? */ 1274 if ((xattr_obj = zp->z_phys->zp_xattr) != 0) { 1275 /* XXX - do we need this if we are deleting? */ 1276 dmu_tx_hold_bonus(tx, xattr_obj); 1277 } 1278 1279 /* are there any additional acls */ 1280 if ((acl_obj = zp->z_phys->zp_acl.z_acl_extern_obj) != 0 && 1281 may_delete_now) 1282 dmu_tx_hold_free(tx, acl_obj, 0, DMU_OBJECT_END); 1283 1284 /* charge as an update -- would be nice not to charge at all */ 1285 dmu_tx_hold_zap(tx, zfsvfs->z_unlinkedobj, FALSE, NULL); 1286 1287 error = dmu_tx_assign(tx, zfsvfs->z_assign); 1288 if (error) { 1289 zfs_dirent_unlock(dl); 1290 VN_RELE(vp); 1291 if (error == ERESTART && zfsvfs->z_assign == TXG_NOWAIT) { 1292 dmu_tx_wait(tx); 1293 dmu_tx_abort(tx); 1294 goto top; 1295 } 1296 dmu_tx_abort(tx); 1297 ZFS_EXIT(zfsvfs); 1298 return (error); 1299 } 1300 1301 /* 1302 * Remove the directory entry. 1303 */ 1304 error = zfs_link_destroy(dl, zp, tx, 0, &unlinked); 1305 1306 if (error) { 1307 dmu_tx_commit(tx); 1308 goto out; 1309 } 1310 1311 if (unlinked) { 1312 mutex_enter(&vp->v_lock); 1313 delete_now = may_delete_now && 1314 vp->v_count == 1 && !vn_has_cached_data(vp) && 1315 zp->z_phys->zp_xattr == xattr_obj && 1316 zp->z_phys->zp_acl.z_acl_extern_obj == acl_obj; 1317 mutex_exit(&vp->v_lock); 1318 } 1319 1320 if (delete_now) { 1321 if (zp->z_phys->zp_xattr) { 1322 error = zfs_zget(zfsvfs, zp->z_phys->zp_xattr, &xzp); 1323 ASSERT3U(error, ==, 0); 1324 ASSERT3U(xzp->z_phys->zp_links, ==, 2); 1325 dmu_buf_will_dirty(xzp->z_dbuf, tx); 1326 mutex_enter(&xzp->z_lock); 1327 xzp->z_unlinked = 1; 1328 xzp->z_phys->zp_links = 0; 1329 mutex_exit(&xzp->z_lock); 1330 zfs_unlinked_add(xzp, tx); 1331 zp->z_phys->zp_xattr = 0; /* probably unnecessary */ 1332 } 1333 mutex_enter(&zp->z_lock); 1334 mutex_enter(&vp->v_lock); 1335 vp->v_count--; 1336 ASSERT3U(vp->v_count, ==, 0); 1337 mutex_exit(&vp->v_lock); 1338 mutex_exit(&zp->z_lock); 1339 zfs_znode_delete(zp, tx); 1340 VFS_RELE(zfsvfs->z_vfs); 1341 } else if (unlinked) { 1342 zfs_unlinked_add(zp, tx); 1343 } 1344 1345 zfs_log_remove(zilog, tx, TX_REMOVE, dzp, name); 1346 1347 dmu_tx_commit(tx); 1348 out: 1349 zfs_dirent_unlock(dl); 1350 1351 if (!delete_now) { 1352 VN_RELE(vp); 1353 } else if (xzp) { 1354 /* this rele delayed to prevent nesting transactions */ 1355 VN_RELE(ZTOV(xzp)); 1356 } 1357 1358 ZFS_EXIT(zfsvfs); 1359 return (error); 1360 } 1361 1362 /* 1363 * Create a new directory and insert it into dvp using the name 1364 * provided. Return a pointer to the inserted directory. 1365 * 1366 * IN: dvp - vnode of directory to add subdir to. 1367 * dirname - name of new directory. 1368 * vap - attributes of new directory. 1369 * cr - credentials of caller. 1370 * 1371 * OUT: vpp - vnode of created directory. 1372 * 1373 * RETURN: 0 if success 1374 * error code if failure 1375 * 1376 * Timestamps: 1377 * dvp - ctime|mtime updated 1378 * vp - ctime|mtime|atime updated 1379 */ 1380 static int 1381 zfs_mkdir(vnode_t *dvp, char *dirname, vattr_t *vap, vnode_t **vpp, cred_t *cr) 1382 { 1383 znode_t *zp, *dzp = VTOZ(dvp); 1384 zfsvfs_t *zfsvfs = dzp->z_zfsvfs; 1385 zilog_t *zilog = zfsvfs->z_log; 1386 zfs_dirlock_t *dl; 1387 uint64_t zoid = 0; 1388 dmu_tx_t *tx; 1389 int error; 1390 1391 ASSERT(vap->va_type == VDIR); 1392 1393 ZFS_ENTER(zfsvfs); 1394 1395 if (dzp->z_phys->zp_flags & ZFS_XATTR) { 1396 ZFS_EXIT(zfsvfs); 1397 return (EINVAL); 1398 } 1399 top: 1400 *vpp = NULL; 1401 1402 /* 1403 * First make sure the new directory doesn't exist. 1404 */ 1405 if (error = zfs_dirent_lock(&dl, dzp, dirname, &zp, ZNEW)) { 1406 ZFS_EXIT(zfsvfs); 1407 return (error); 1408 } 1409 1410 if (error = zfs_zaccess(dzp, ACE_ADD_SUBDIRECTORY, cr)) { 1411 zfs_dirent_unlock(dl); 1412 ZFS_EXIT(zfsvfs); 1413 return (error); 1414 } 1415 1416 /* 1417 * Add a new entry to the directory. 1418 */ 1419 tx = dmu_tx_create(zfsvfs->z_os); 1420 dmu_tx_hold_zap(tx, dzp->z_id, TRUE, dirname); 1421 dmu_tx_hold_zap(tx, DMU_NEW_OBJECT, FALSE, NULL); 1422 if (dzp->z_phys->zp_flags & ZFS_INHERIT_ACE) 1423 dmu_tx_hold_write(tx, DMU_NEW_OBJECT, 1424 0, SPA_MAXBLOCKSIZE); 1425 error = dmu_tx_assign(tx, zfsvfs->z_assign); 1426 if (error) { 1427 zfs_dirent_unlock(dl); 1428 if (error == ERESTART && zfsvfs->z_assign == TXG_NOWAIT) { 1429 dmu_tx_wait(tx); 1430 dmu_tx_abort(tx); 1431 goto top; 1432 } 1433 dmu_tx_abort(tx); 1434 ZFS_EXIT(zfsvfs); 1435 return (error); 1436 } 1437 1438 /* 1439 * Create new node. 1440 */ 1441 zfs_mknode(dzp, vap, &zoid, tx, cr, 0, &zp, 0); 1442 1443 /* 1444 * Now put new name in parent dir. 1445 */ 1446 (void) zfs_link_create(dl, zp, tx, ZNEW); 1447 1448 *vpp = ZTOV(zp); 1449 1450 zfs_log_create(zilog, tx, TX_MKDIR, dzp, zp, dirname); 1451 dmu_tx_commit(tx); 1452 1453 zfs_dirent_unlock(dl); 1454 1455 ZFS_EXIT(zfsvfs); 1456 return (0); 1457 } 1458 1459 /* 1460 * Remove a directory subdir entry. If the current working 1461 * directory is the same as the subdir to be removed, the 1462 * remove will fail. 1463 * 1464 * IN: dvp - vnode of directory to remove from. 1465 * name - name of directory to be removed. 1466 * cwd - vnode of current working directory. 1467 * cr - credentials of caller. 1468 * 1469 * RETURN: 0 if success 1470 * error code if failure 1471 * 1472 * Timestamps: 1473 * dvp - ctime|mtime updated 1474 */ 1475 static int 1476 zfs_rmdir(vnode_t *dvp, char *name, vnode_t *cwd, cred_t *cr) 1477 { 1478 znode_t *dzp = VTOZ(dvp); 1479 znode_t *zp; 1480 vnode_t *vp; 1481 zfsvfs_t *zfsvfs = dzp->z_zfsvfs; 1482 zilog_t *zilog = zfsvfs->z_log; 1483 zfs_dirlock_t *dl; 1484 dmu_tx_t *tx; 1485 int error; 1486 1487 ZFS_ENTER(zfsvfs); 1488 1489 top: 1490 zp = NULL; 1491 1492 /* 1493 * Attempt to lock directory; fail if entry doesn't exist. 1494 */ 1495 if (error = zfs_dirent_lock(&dl, dzp, name, &zp, ZEXISTS)) { 1496 ZFS_EXIT(zfsvfs); 1497 return (error); 1498 } 1499 1500 vp = ZTOV(zp); 1501 1502 if (error = zfs_zaccess_delete(dzp, zp, cr)) { 1503 goto out; 1504 } 1505 1506 if (vp->v_type != VDIR) { 1507 error = ENOTDIR; 1508 goto out; 1509 } 1510 1511 if (vp == cwd) { 1512 error = EINVAL; 1513 goto out; 1514 } 1515 1516 vnevent_rmdir(vp); 1517 1518 /* 1519 * Grab a lock on the directory to make sure that noone is 1520 * trying to add (or lookup) entries while we are removing it. 1521 */ 1522 rw_enter(&zp->z_name_lock, RW_WRITER); 1523 1524 /* 1525 * Grab a lock on the parent pointer to make sure we play well 1526 * with the treewalk and directory rename code. 1527 */ 1528 rw_enter(&zp->z_parent_lock, RW_WRITER); 1529 1530 tx = dmu_tx_create(zfsvfs->z_os); 1531 dmu_tx_hold_zap(tx, dzp->z_id, FALSE, name); 1532 dmu_tx_hold_bonus(tx, zp->z_id); 1533 dmu_tx_hold_zap(tx, zfsvfs->z_unlinkedobj, FALSE, NULL); 1534 error = dmu_tx_assign(tx, zfsvfs->z_assign); 1535 if (error) { 1536 rw_exit(&zp->z_parent_lock); 1537 rw_exit(&zp->z_name_lock); 1538 zfs_dirent_unlock(dl); 1539 VN_RELE(vp); 1540 if (error == ERESTART && zfsvfs->z_assign == TXG_NOWAIT) { 1541 dmu_tx_wait(tx); 1542 dmu_tx_abort(tx); 1543 goto top; 1544 } 1545 dmu_tx_abort(tx); 1546 ZFS_EXIT(zfsvfs); 1547 return (error); 1548 } 1549 1550 error = zfs_link_destroy(dl, zp, tx, 0, NULL); 1551 1552 if (error == 0) 1553 zfs_log_remove(zilog, tx, TX_RMDIR, dzp, name); 1554 1555 dmu_tx_commit(tx); 1556 1557 rw_exit(&zp->z_parent_lock); 1558 rw_exit(&zp->z_name_lock); 1559 out: 1560 zfs_dirent_unlock(dl); 1561 1562 VN_RELE(vp); 1563 1564 ZFS_EXIT(zfsvfs); 1565 return (error); 1566 } 1567 1568 /* 1569 * Read as many directory entries as will fit into the provided 1570 * buffer from the given directory cursor position (specified in 1571 * the uio structure. 1572 * 1573 * IN: vp - vnode of directory to read. 1574 * uio - structure supplying read location, range info, 1575 * and return buffer. 1576 * cr - credentials of caller. 1577 * 1578 * OUT: uio - updated offset and range, buffer filled. 1579 * eofp - set to true if end-of-file detected. 1580 * 1581 * RETURN: 0 if success 1582 * error code if failure 1583 * 1584 * Timestamps: 1585 * vp - atime updated 1586 * 1587 * Note that the low 4 bits of the cookie returned by zap is always zero. 1588 * This allows us to use the low range for "special" directory entries: 1589 * We use 0 for '.', and 1 for '..'. If this is the root of the filesystem, 1590 * we use the offset 2 for the '.zfs' directory. 1591 */ 1592 /* ARGSUSED */ 1593 static int 1594 zfs_readdir(vnode_t *vp, uio_t *uio, cred_t *cr, int *eofp) 1595 { 1596 znode_t *zp = VTOZ(vp); 1597 iovec_t *iovp; 1598 dirent64_t *odp; 1599 zfsvfs_t *zfsvfs = zp->z_zfsvfs; 1600 objset_t *os; 1601 caddr_t outbuf; 1602 size_t bufsize; 1603 zap_cursor_t zc; 1604 zap_attribute_t zap; 1605 uint_t bytes_wanted; 1606 uint64_t offset; /* must be unsigned; checks for < 1 */ 1607 int local_eof; 1608 int outcount; 1609 int error; 1610 uint8_t prefetch; 1611 1612 ZFS_ENTER(zfsvfs); 1613 1614 /* 1615 * If we are not given an eof variable, 1616 * use a local one. 1617 */ 1618 if (eofp == NULL) 1619 eofp = &local_eof; 1620 1621 /* 1622 * Check for valid iov_len. 1623 */ 1624 if (uio->uio_iov->iov_len <= 0) { 1625 ZFS_EXIT(zfsvfs); 1626 return (EINVAL); 1627 } 1628 1629 /* 1630 * Quit if directory has been removed (posix) 1631 */ 1632 if ((*eofp = zp->z_unlinked) != 0) { 1633 ZFS_EXIT(zfsvfs); 1634 return (0); 1635 } 1636 1637 error = 0; 1638 os = zfsvfs->z_os; 1639 offset = uio->uio_loffset; 1640 prefetch = zp->z_zn_prefetch; 1641 1642 /* 1643 * Initialize the iterator cursor. 1644 */ 1645 if (offset <= 3) { 1646 /* 1647 * Start iteration from the beginning of the directory. 1648 */ 1649 zap_cursor_init(&zc, os, zp->z_id); 1650 } else { 1651 /* 1652 * The offset is a serialized cursor. 1653 */ 1654 zap_cursor_init_serialized(&zc, os, zp->z_id, offset); 1655 } 1656 1657 /* 1658 * Get space to change directory entries into fs independent format. 1659 */ 1660 iovp = uio->uio_iov; 1661 bytes_wanted = iovp->iov_len; 1662 if (uio->uio_segflg != UIO_SYSSPACE || uio->uio_iovcnt != 1) { 1663 bufsize = bytes_wanted; 1664 outbuf = kmem_alloc(bufsize, KM_SLEEP); 1665 odp = (struct dirent64 *)outbuf; 1666 } else { 1667 bufsize = bytes_wanted; 1668 odp = (struct dirent64 *)iovp->iov_base; 1669 } 1670 1671 /* 1672 * Transform to file-system independent format 1673 */ 1674 outcount = 0; 1675 while (outcount < bytes_wanted) { 1676 ino64_t objnum; 1677 ushort_t reclen; 1678 off64_t *next; 1679 1680 /* 1681 * Special case `.', `..', and `.zfs'. 1682 */ 1683 if (offset == 0) { 1684 (void) strcpy(zap.za_name, "."); 1685 objnum = zp->z_id; 1686 } else if (offset == 1) { 1687 (void) strcpy(zap.za_name, ".."); 1688 objnum = zp->z_phys->zp_parent; 1689 } else if (offset == 2 && zfs_show_ctldir(zp)) { 1690 (void) strcpy(zap.za_name, ZFS_CTLDIR_NAME); 1691 objnum = ZFSCTL_INO_ROOT; 1692 } else { 1693 /* 1694 * Grab next entry. 1695 */ 1696 if (error = zap_cursor_retrieve(&zc, &zap)) { 1697 if ((*eofp = (error == ENOENT)) != 0) 1698 break; 1699 else 1700 goto update; 1701 } 1702 1703 if (zap.za_integer_length != 8 || 1704 zap.za_num_integers != 1) { 1705 cmn_err(CE_WARN, "zap_readdir: bad directory " 1706 "entry, obj = %lld, offset = %lld\n", 1707 (u_longlong_t)zp->z_id, 1708 (u_longlong_t)offset); 1709 error = ENXIO; 1710 goto update; 1711 } 1712 1713 objnum = ZFS_DIRENT_OBJ(zap.za_first_integer); 1714 /* 1715 * MacOS X can extract the object type here such as: 1716 * uint8_t type = ZFS_DIRENT_TYPE(zap.za_first_integer); 1717 */ 1718 } 1719 reclen = DIRENT64_RECLEN(strlen(zap.za_name)); 1720 1721 /* 1722 * Will this entry fit in the buffer? 1723 */ 1724 if (outcount + reclen > bufsize) { 1725 /* 1726 * Did we manage to fit anything in the buffer? 1727 */ 1728 if (!outcount) { 1729 error = EINVAL; 1730 goto update; 1731 } 1732 break; 1733 } 1734 /* 1735 * Add this entry: 1736 */ 1737 odp->d_ino = objnum; 1738 odp->d_reclen = reclen; 1739 /* NOTE: d_off is the offset for the *next* entry */ 1740 next = &(odp->d_off); 1741 (void) strncpy(odp->d_name, zap.za_name, 1742 DIRENT64_NAMELEN(reclen)); 1743 outcount += reclen; 1744 odp = (dirent64_t *)((intptr_t)odp + reclen); 1745 1746 ASSERT(outcount <= bufsize); 1747 1748 /* Prefetch znode */ 1749 if (prefetch) 1750 dmu_prefetch(os, objnum, 0, 0); 1751 1752 /* 1753 * Move to the next entry, fill in the previous offset. 1754 */ 1755 if (offset > 2 || (offset == 2 && !zfs_show_ctldir(zp))) { 1756 zap_cursor_advance(&zc); 1757 offset = zap_cursor_serialize(&zc); 1758 } else { 1759 offset += 1; 1760 } 1761 *next = offset; 1762 } 1763 zp->z_zn_prefetch = B_FALSE; /* a lookup will re-enable pre-fetching */ 1764 1765 if (uio->uio_segflg == UIO_SYSSPACE && uio->uio_iovcnt == 1) { 1766 iovp->iov_base += outcount; 1767 iovp->iov_len -= outcount; 1768 uio->uio_resid -= outcount; 1769 } else if (error = uiomove(outbuf, (long)outcount, UIO_READ, uio)) { 1770 /* 1771 * Reset the pointer. 1772 */ 1773 offset = uio->uio_loffset; 1774 } 1775 1776 update: 1777 zap_cursor_fini(&zc); 1778 if (uio->uio_segflg != UIO_SYSSPACE || uio->uio_iovcnt != 1) 1779 kmem_free(outbuf, bufsize); 1780 1781 if (error == ENOENT) 1782 error = 0; 1783 1784 ZFS_ACCESSTIME_STAMP(zfsvfs, zp); 1785 1786 uio->uio_loffset = offset; 1787 ZFS_EXIT(zfsvfs); 1788 return (error); 1789 } 1790 1791 static int 1792 zfs_fsync(vnode_t *vp, int syncflag, cred_t *cr) 1793 { 1794 znode_t *zp = VTOZ(vp); 1795 zfsvfs_t *zfsvfs = zp->z_zfsvfs; 1796 1797 /* 1798 * Regardless of whether this is required for standards conformance, 1799 * this is the logical behavior when fsync() is called on a file with 1800 * dirty pages. We use B_ASYNC since the ZIL transactions are already 1801 * going to be pushed out as part of the zil_commit(). 1802 */ 1803 if (vn_has_cached_data(vp) && !(syncflag & FNODSYNC) && 1804 (vp->v_type == VREG) && !(IS_SWAPVP(vp))) 1805 (void) VOP_PUTPAGE(vp, (offset_t)0, (size_t)0, B_ASYNC, cr); 1806 1807 ZFS_ENTER(zfsvfs); 1808 zil_commit(zfsvfs->z_log, zp->z_last_itx, zp->z_id); 1809 ZFS_EXIT(zfsvfs); 1810 return (0); 1811 } 1812 1813 /* 1814 * Get the requested file attributes and place them in the provided 1815 * vattr structure. 1816 * 1817 * IN: vp - vnode of file. 1818 * vap - va_mask identifies requested attributes. 1819 * flags - [UNUSED] 1820 * cr - credentials of caller. 1821 * 1822 * OUT: vap - attribute values. 1823 * 1824 * RETURN: 0 (always succeeds) 1825 */ 1826 /* ARGSUSED */ 1827 static int 1828 zfs_getattr(vnode_t *vp, vattr_t *vap, int flags, cred_t *cr) 1829 { 1830 znode_t *zp = VTOZ(vp); 1831 zfsvfs_t *zfsvfs = zp->z_zfsvfs; 1832 znode_phys_t *pzp = zp->z_phys; 1833 int error; 1834 uint64_t links; 1835 1836 ZFS_ENTER(zfsvfs); 1837 1838 /* 1839 * Return all attributes. It's cheaper to provide the answer 1840 * than to determine whether we were asked the question. 1841 */ 1842 mutex_enter(&zp->z_lock); 1843 1844 vap->va_type = vp->v_type; 1845 vap->va_mode = pzp->zp_mode & MODEMASK; 1846 vap->va_uid = zp->z_phys->zp_uid; 1847 vap->va_gid = zp->z_phys->zp_gid; 1848 vap->va_fsid = zp->z_zfsvfs->z_vfs->vfs_dev; 1849 vap->va_nodeid = zp->z_id; 1850 if ((vp->v_flag & VROOT) && zfs_show_ctldir(zp)) 1851 links = pzp->zp_links + 1; 1852 else 1853 links = pzp->zp_links; 1854 vap->va_nlink = MIN(links, UINT32_MAX); /* nlink_t limit! */ 1855 vap->va_size = pzp->zp_size; 1856 vap->va_rdev = vp->v_rdev; 1857 vap->va_seq = zp->z_seq; 1858 1859 ZFS_TIME_DECODE(&vap->va_atime, pzp->zp_atime); 1860 ZFS_TIME_DECODE(&vap->va_mtime, pzp->zp_mtime); 1861 ZFS_TIME_DECODE(&vap->va_ctime, pzp->zp_ctime); 1862 1863 /* 1864 * If ACL is trivial don't bother looking for ACE_READ_ATTRIBUTES. 1865 * Also, if we are the owner don't bother, since owner should 1866 * always be allowed to read basic attributes of file. 1867 */ 1868 if (!(zp->z_phys->zp_flags & ZFS_ACL_TRIVIAL) && 1869 (zp->z_phys->zp_uid != crgetuid(cr))) { 1870 if (error = zfs_zaccess(zp, ACE_READ_ATTRIBUTES, cr)) { 1871 mutex_exit(&zp->z_lock); 1872 ZFS_EXIT(zfsvfs); 1873 return (error); 1874 } 1875 } 1876 1877 mutex_exit(&zp->z_lock); 1878 1879 dmu_object_size_from_db(zp->z_dbuf, &vap->va_blksize, &vap->va_nblocks); 1880 1881 if (zp->z_blksz == 0) { 1882 /* 1883 * Block size hasn't been set; suggest maximal I/O transfers. 1884 */ 1885 vap->va_blksize = zfsvfs->z_max_blksz; 1886 } 1887 1888 ZFS_EXIT(zfsvfs); 1889 return (0); 1890 } 1891 1892 /* 1893 * Set the file attributes to the values contained in the 1894 * vattr structure. 1895 * 1896 * IN: vp - vnode of file to be modified. 1897 * vap - new attribute values. 1898 * flags - ATTR_UTIME set if non-default time values provided. 1899 * cr - credentials of caller. 1900 * 1901 * RETURN: 0 if success 1902 * error code if failure 1903 * 1904 * Timestamps: 1905 * vp - ctime updated, mtime updated if size changed. 1906 */ 1907 /* ARGSUSED */ 1908 static int 1909 zfs_setattr(vnode_t *vp, vattr_t *vap, int flags, cred_t *cr, 1910 caller_context_t *ct) 1911 { 1912 struct znode *zp = VTOZ(vp); 1913 znode_phys_t *pzp = zp->z_phys; 1914 zfsvfs_t *zfsvfs = zp->z_zfsvfs; 1915 zilog_t *zilog = zfsvfs->z_log; 1916 dmu_tx_t *tx; 1917 vattr_t oldva; 1918 uint_t mask = vap->va_mask; 1919 uint_t saved_mask; 1920 int trim_mask = 0; 1921 uint64_t new_mode; 1922 znode_t *attrzp; 1923 int need_policy = FALSE; 1924 int err; 1925 1926 if (mask == 0) 1927 return (0); 1928 1929 if (mask & AT_NOSET) 1930 return (EINVAL); 1931 1932 if (mask & AT_SIZE && vp->v_type == VDIR) 1933 return (EISDIR); 1934 1935 if (mask & AT_SIZE && vp->v_type != VREG && vp->v_type != VFIFO) 1936 return (EINVAL); 1937 1938 ZFS_ENTER(zfsvfs); 1939 1940 top: 1941 attrzp = NULL; 1942 1943 if (zfsvfs->z_vfs->vfs_flag & VFS_RDONLY) { 1944 ZFS_EXIT(zfsvfs); 1945 return (EROFS); 1946 } 1947 1948 /* 1949 * First validate permissions 1950 */ 1951 1952 if (mask & AT_SIZE) { 1953 err = zfs_zaccess(zp, ACE_WRITE_DATA, cr); 1954 if (err) { 1955 ZFS_EXIT(zfsvfs); 1956 return (err); 1957 } 1958 /* 1959 * XXX - Note, we are not providing any open 1960 * mode flags here (like FNDELAY), so we may 1961 * block if there are locks present... this 1962 * should be addressed in openat(). 1963 */ 1964 do { 1965 err = zfs_freesp(zp, vap->va_size, 0, 0, FALSE); 1966 /* NB: we already did dmu_tx_wait() if necessary */ 1967 } while (err == ERESTART && zfsvfs->z_assign == TXG_NOWAIT); 1968 if (err) { 1969 ZFS_EXIT(zfsvfs); 1970 return (err); 1971 } 1972 } 1973 1974 if (mask & (AT_ATIME|AT_MTIME)) 1975 need_policy = zfs_zaccess_v4_perm(zp, ACE_WRITE_ATTRIBUTES, cr); 1976 1977 if (mask & (AT_UID|AT_GID)) { 1978 int idmask = (mask & (AT_UID|AT_GID)); 1979 int take_owner; 1980 int take_group; 1981 1982 /* 1983 * NOTE: even if a new mode is being set, 1984 * we may clear S_ISUID/S_ISGID bits. 1985 */ 1986 1987 if (!(mask & AT_MODE)) 1988 vap->va_mode = pzp->zp_mode; 1989 1990 /* 1991 * Take ownership or chgrp to group we are a member of 1992 */ 1993 1994 take_owner = (mask & AT_UID) && (vap->va_uid == crgetuid(cr)); 1995 take_group = (mask & AT_GID) && groupmember(vap->va_gid, cr); 1996 1997 /* 1998 * If both AT_UID and AT_GID are set then take_owner and 1999 * take_group must both be set in order to allow taking 2000 * ownership. 2001 * 2002 * Otherwise, send the check through secpolicy_vnode_setattr() 2003 * 2004 */ 2005 2006 if (((idmask == (AT_UID|AT_GID)) && take_owner && take_group) || 2007 ((idmask == AT_UID) && take_owner) || 2008 ((idmask == AT_GID) && take_group)) { 2009 if (zfs_zaccess_v4_perm(zp, ACE_WRITE_OWNER, cr) == 0) { 2010 /* 2011 * Remove setuid/setgid for non-privileged users 2012 */ 2013 secpolicy_setid_clear(vap, cr); 2014 trim_mask = (mask & (AT_UID|AT_GID)); 2015 } else { 2016 need_policy = TRUE; 2017 } 2018 } else { 2019 need_policy = TRUE; 2020 } 2021 } 2022 2023 mutex_enter(&zp->z_lock); 2024 oldva.va_mode = pzp->zp_mode; 2025 oldva.va_uid = zp->z_phys->zp_uid; 2026 oldva.va_gid = zp->z_phys->zp_gid; 2027 mutex_exit(&zp->z_lock); 2028 2029 if (mask & AT_MODE) { 2030 if (zfs_zaccess_v4_perm(zp, ACE_WRITE_ACL, cr) == 0) { 2031 err = secpolicy_setid_setsticky_clear(vp, vap, 2032 &oldva, cr); 2033 if (err) { 2034 ZFS_EXIT(zfsvfs); 2035 return (err); 2036 } 2037 trim_mask |= AT_MODE; 2038 } else { 2039 need_policy = TRUE; 2040 } 2041 } 2042 2043 if (need_policy) { 2044 /* 2045 * If trim_mask is set then take ownership 2046 * has been granted or write_acl is present and user 2047 * has the ability to modify mode. In that case remove 2048 * UID|GID and or MODE from mask so that 2049 * secpolicy_vnode_setattr() doesn't revoke it. 2050 */ 2051 2052 if (trim_mask) { 2053 saved_mask = vap->va_mask; 2054 vap->va_mask &= ~trim_mask; 2055 2056 } 2057 err = secpolicy_vnode_setattr(cr, vp, vap, &oldva, flags, 2058 (int (*)(void *, int, cred_t *))zfs_zaccess_rwx, zp); 2059 if (err) { 2060 ZFS_EXIT(zfsvfs); 2061 return (err); 2062 } 2063 2064 if (trim_mask) 2065 vap->va_mask |= saved_mask; 2066 } 2067 2068 /* 2069 * secpolicy_vnode_setattr, or take ownership may have 2070 * changed va_mask 2071 */ 2072 mask = vap->va_mask; 2073 2074 tx = dmu_tx_create(zfsvfs->z_os); 2075 dmu_tx_hold_bonus(tx, zp->z_id); 2076 2077 if (mask & AT_MODE) { 2078 uint64_t pmode = pzp->zp_mode; 2079 2080 new_mode = (pmode & S_IFMT) | (vap->va_mode & ~S_IFMT); 2081 2082 if (zp->z_phys->zp_acl.z_acl_extern_obj) 2083 dmu_tx_hold_write(tx, 2084 pzp->zp_acl.z_acl_extern_obj, 0, SPA_MAXBLOCKSIZE); 2085 else 2086 dmu_tx_hold_write(tx, DMU_NEW_OBJECT, 2087 0, ZFS_ACL_SIZE(MAX_ACL_SIZE)); 2088 } 2089 2090 if ((mask & (AT_UID | AT_GID)) && zp->z_phys->zp_xattr != 0) { 2091 err = zfs_zget(zp->z_zfsvfs, zp->z_phys->zp_xattr, &attrzp); 2092 if (err) { 2093 dmu_tx_abort(tx); 2094 ZFS_EXIT(zfsvfs); 2095 return (err); 2096 } 2097 dmu_tx_hold_bonus(tx, attrzp->z_id); 2098 } 2099 2100 err = dmu_tx_assign(tx, zfsvfs->z_assign); 2101 if (err) { 2102 if (attrzp) 2103 VN_RELE(ZTOV(attrzp)); 2104 if (err == ERESTART && zfsvfs->z_assign == TXG_NOWAIT) { 2105 dmu_tx_wait(tx); 2106 dmu_tx_abort(tx); 2107 goto top; 2108 } 2109 dmu_tx_abort(tx); 2110 ZFS_EXIT(zfsvfs); 2111 return (err); 2112 } 2113 2114 dmu_buf_will_dirty(zp->z_dbuf, tx); 2115 2116 /* 2117 * Set each attribute requested. 2118 * We group settings according to the locks they need to acquire. 2119 * 2120 * Note: you cannot set ctime directly, although it will be 2121 * updated as a side-effect of calling this function. 2122 */ 2123 2124 mutex_enter(&zp->z_lock); 2125 2126 if (mask & AT_MODE) { 2127 err = zfs_acl_chmod_setattr(zp, new_mode, tx); 2128 ASSERT3U(err, ==, 0); 2129 } 2130 2131 if (attrzp) 2132 mutex_enter(&attrzp->z_lock); 2133 2134 if (mask & AT_UID) { 2135 zp->z_phys->zp_uid = (uint64_t)vap->va_uid; 2136 if (attrzp) { 2137 attrzp->z_phys->zp_uid = (uint64_t)vap->va_uid; 2138 } 2139 } 2140 2141 if (mask & AT_GID) { 2142 zp->z_phys->zp_gid = (uint64_t)vap->va_gid; 2143 if (attrzp) 2144 attrzp->z_phys->zp_gid = (uint64_t)vap->va_gid; 2145 } 2146 2147 if (attrzp) 2148 mutex_exit(&attrzp->z_lock); 2149 2150 if (mask & AT_ATIME) 2151 ZFS_TIME_ENCODE(&vap->va_atime, pzp->zp_atime); 2152 2153 if (mask & AT_MTIME) 2154 ZFS_TIME_ENCODE(&vap->va_mtime, pzp->zp_mtime); 2155 2156 if (mask & AT_SIZE) 2157 zfs_time_stamper_locked(zp, CONTENT_MODIFIED, tx); 2158 else if (mask != 0) 2159 zfs_time_stamper_locked(zp, STATE_CHANGED, tx); 2160 2161 if (mask != 0) 2162 zfs_log_setattr(zilog, tx, TX_SETATTR, zp, vap, mask); 2163 2164 mutex_exit(&zp->z_lock); 2165 2166 if (attrzp) 2167 VN_RELE(ZTOV(attrzp)); 2168 2169 dmu_tx_commit(tx); 2170 2171 ZFS_EXIT(zfsvfs); 2172 return (err); 2173 } 2174 2175 typedef struct zfs_zlock { 2176 krwlock_t *zl_rwlock; /* lock we acquired */ 2177 znode_t *zl_znode; /* znode we held */ 2178 struct zfs_zlock *zl_next; /* next in list */ 2179 } zfs_zlock_t; 2180 2181 /* 2182 * Drop locks and release vnodes that were held by zfs_rename_lock(). 2183 */ 2184 static void 2185 zfs_rename_unlock(zfs_zlock_t **zlpp) 2186 { 2187 zfs_zlock_t *zl; 2188 2189 while ((zl = *zlpp) != NULL) { 2190 if (zl->zl_znode != NULL) 2191 VN_RELE(ZTOV(zl->zl_znode)); 2192 rw_exit(zl->zl_rwlock); 2193 *zlpp = zl->zl_next; 2194 kmem_free(zl, sizeof (*zl)); 2195 } 2196 } 2197 2198 /* 2199 * Search back through the directory tree, using the ".." entries. 2200 * Lock each directory in the chain to prevent concurrent renames. 2201 * Fail any attempt to move a directory into one of its own descendants. 2202 * XXX - z_parent_lock can overlap with map or grow locks 2203 */ 2204 static int 2205 zfs_rename_lock(znode_t *szp, znode_t *tdzp, znode_t *sdzp, zfs_zlock_t **zlpp) 2206 { 2207 zfs_zlock_t *zl; 2208 znode_t *zp = tdzp; 2209 uint64_t rootid = zp->z_zfsvfs->z_root; 2210 uint64_t *oidp = &zp->z_id; 2211 krwlock_t *rwlp = &szp->z_parent_lock; 2212 krw_t rw = RW_WRITER; 2213 2214 /* 2215 * First pass write-locks szp and compares to zp->z_id. 2216 * Later passes read-lock zp and compare to zp->z_parent. 2217 */ 2218 do { 2219 if (!rw_tryenter(rwlp, rw)) { 2220 /* 2221 * Another thread is renaming in this path. 2222 * Note that if we are a WRITER, we don't have any 2223 * parent_locks held yet. 2224 */ 2225 if (rw == RW_READER && zp->z_id > szp->z_id) { 2226 /* 2227 * Drop our locks and restart 2228 */ 2229 zfs_rename_unlock(&zl); 2230 *zlpp = NULL; 2231 zp = tdzp; 2232 oidp = &zp->z_id; 2233 rwlp = &szp->z_parent_lock; 2234 rw = RW_WRITER; 2235 continue; 2236 } else { 2237 /* 2238 * Wait for other thread to drop its locks 2239 */ 2240 rw_enter(rwlp, rw); 2241 } 2242 } 2243 2244 zl = kmem_alloc(sizeof (*zl), KM_SLEEP); 2245 zl->zl_rwlock = rwlp; 2246 zl->zl_znode = NULL; 2247 zl->zl_next = *zlpp; 2248 *zlpp = zl; 2249 2250 if (*oidp == szp->z_id) /* We're a descendant of szp */ 2251 return (EINVAL); 2252 2253 if (*oidp == rootid) /* We've hit the top */ 2254 return (0); 2255 2256 if (rw == RW_READER) { /* i.e. not the first pass */ 2257 int error = zfs_zget(zp->z_zfsvfs, *oidp, &zp); 2258 if (error) 2259 return (error); 2260 zl->zl_znode = zp; 2261 } 2262 oidp = &zp->z_phys->zp_parent; 2263 rwlp = &zp->z_parent_lock; 2264 rw = RW_READER; 2265 2266 } while (zp->z_id != sdzp->z_id); 2267 2268 return (0); 2269 } 2270 2271 /* 2272 * Move an entry from the provided source directory to the target 2273 * directory. Change the entry name as indicated. 2274 * 2275 * IN: sdvp - Source directory containing the "old entry". 2276 * snm - Old entry name. 2277 * tdvp - Target directory to contain the "new entry". 2278 * tnm - New entry name. 2279 * cr - credentials of caller. 2280 * 2281 * RETURN: 0 if success 2282 * error code if failure 2283 * 2284 * Timestamps: 2285 * sdvp,tdvp - ctime|mtime updated 2286 */ 2287 static int 2288 zfs_rename(vnode_t *sdvp, char *snm, vnode_t *tdvp, char *tnm, cred_t *cr) 2289 { 2290 znode_t *tdzp, *szp, *tzp; 2291 znode_t *sdzp = VTOZ(sdvp); 2292 zfsvfs_t *zfsvfs = sdzp->z_zfsvfs; 2293 zilog_t *zilog = zfsvfs->z_log; 2294 vnode_t *realvp; 2295 zfs_dirlock_t *sdl, *tdl; 2296 dmu_tx_t *tx; 2297 zfs_zlock_t *zl; 2298 int cmp, serr, terr, error; 2299 2300 ZFS_ENTER(zfsvfs); 2301 2302 /* 2303 * Make sure we have the real vp for the target directory. 2304 */ 2305 if (VOP_REALVP(tdvp, &realvp) == 0) 2306 tdvp = realvp; 2307 2308 if (tdvp->v_vfsp != sdvp->v_vfsp) { 2309 ZFS_EXIT(zfsvfs); 2310 return (EXDEV); 2311 } 2312 2313 tdzp = VTOZ(tdvp); 2314 top: 2315 szp = NULL; 2316 tzp = NULL; 2317 zl = NULL; 2318 2319 /* 2320 * This is to prevent the creation of links into attribute space 2321 * by renaming a linked file into/outof an attribute directory. 2322 * See the comment in zfs_link() for why this is considered bad. 2323 */ 2324 if ((tdzp->z_phys->zp_flags & ZFS_XATTR) != 2325 (sdzp->z_phys->zp_flags & ZFS_XATTR)) { 2326 ZFS_EXIT(zfsvfs); 2327 return (EINVAL); 2328 } 2329 2330 /* 2331 * Lock source and target directory entries. To prevent deadlock, 2332 * a lock ordering must be defined. We lock the directory with 2333 * the smallest object id first, or if it's a tie, the one with 2334 * the lexically first name. 2335 */ 2336 if (sdzp->z_id < tdzp->z_id) { 2337 cmp = -1; 2338 } else if (sdzp->z_id > tdzp->z_id) { 2339 cmp = 1; 2340 } else { 2341 cmp = strcmp(snm, tnm); 2342 if (cmp == 0) { 2343 /* 2344 * POSIX: "If the old argument and the new argument 2345 * both refer to links to the same existing file, 2346 * the rename() function shall return successfully 2347 * and perform no other action." 2348 */ 2349 ZFS_EXIT(zfsvfs); 2350 return (0); 2351 } 2352 } 2353 if (cmp < 0) { 2354 serr = zfs_dirent_lock(&sdl, sdzp, snm, &szp, ZEXISTS); 2355 terr = zfs_dirent_lock(&tdl, tdzp, tnm, &tzp, 0); 2356 } else { 2357 terr = zfs_dirent_lock(&tdl, tdzp, tnm, &tzp, 0); 2358 serr = zfs_dirent_lock(&sdl, sdzp, snm, &szp, ZEXISTS); 2359 } 2360 2361 if (serr) { 2362 /* 2363 * Source entry invalid or not there. 2364 */ 2365 if (!terr) { 2366 zfs_dirent_unlock(tdl); 2367 if (tzp) 2368 VN_RELE(ZTOV(tzp)); 2369 } 2370 if (strcmp(snm, "..") == 0) 2371 serr = EINVAL; 2372 ZFS_EXIT(zfsvfs); 2373 return (serr); 2374 } 2375 if (terr) { 2376 zfs_dirent_unlock(sdl); 2377 VN_RELE(ZTOV(szp)); 2378 if (strcmp(tnm, "..") == 0) 2379 terr = EINVAL; 2380 ZFS_EXIT(zfsvfs); 2381 return (terr); 2382 } 2383 2384 /* 2385 * Must have write access at the source to remove the old entry 2386 * and write access at the target to create the new entry. 2387 * Note that if target and source are the same, this can be 2388 * done in a single check. 2389 */ 2390 2391 if (error = zfs_zaccess_rename(sdzp, szp, tdzp, tzp, cr)) 2392 goto out; 2393 2394 if (ZTOV(szp)->v_type == VDIR) { 2395 /* 2396 * Check to make sure rename is valid. 2397 * Can't do a move like this: /usr/a/b to /usr/a/b/c/d 2398 */ 2399 if (error = zfs_rename_lock(szp, tdzp, sdzp, &zl)) 2400 goto out; 2401 } 2402 2403 /* 2404 * Does target exist? 2405 */ 2406 if (tzp) { 2407 /* 2408 * Source and target must be the same type. 2409 */ 2410 if (ZTOV(szp)->v_type == VDIR) { 2411 if (ZTOV(tzp)->v_type != VDIR) { 2412 error = ENOTDIR; 2413 goto out; 2414 } 2415 } else { 2416 if (ZTOV(tzp)->v_type == VDIR) { 2417 error = EISDIR; 2418 goto out; 2419 } 2420 } 2421 /* 2422 * POSIX dictates that when the source and target 2423 * entries refer to the same file object, rename 2424 * must do nothing and exit without error. 2425 */ 2426 if (szp->z_id == tzp->z_id) { 2427 error = 0; 2428 goto out; 2429 } 2430 } 2431 2432 vnevent_rename_src(ZTOV(szp)); 2433 if (tzp) 2434 vnevent_rename_dest(ZTOV(tzp)); 2435 2436 tx = dmu_tx_create(zfsvfs->z_os); 2437 dmu_tx_hold_bonus(tx, szp->z_id); /* nlink changes */ 2438 dmu_tx_hold_bonus(tx, sdzp->z_id); /* nlink changes */ 2439 dmu_tx_hold_zap(tx, sdzp->z_id, FALSE, snm); 2440 dmu_tx_hold_zap(tx, tdzp->z_id, TRUE, tnm); 2441 if (sdzp != tdzp) 2442 dmu_tx_hold_bonus(tx, tdzp->z_id); /* nlink changes */ 2443 if (tzp) 2444 dmu_tx_hold_bonus(tx, tzp->z_id); /* parent changes */ 2445 dmu_tx_hold_zap(tx, zfsvfs->z_unlinkedobj, FALSE, NULL); 2446 error = dmu_tx_assign(tx, zfsvfs->z_assign); 2447 if (error) { 2448 if (zl != NULL) 2449 zfs_rename_unlock(&zl); 2450 zfs_dirent_unlock(sdl); 2451 zfs_dirent_unlock(tdl); 2452 VN_RELE(ZTOV(szp)); 2453 if (tzp) 2454 VN_RELE(ZTOV(tzp)); 2455 if (error == ERESTART && zfsvfs->z_assign == TXG_NOWAIT) { 2456 dmu_tx_wait(tx); 2457 dmu_tx_abort(tx); 2458 goto top; 2459 } 2460 dmu_tx_abort(tx); 2461 ZFS_EXIT(zfsvfs); 2462 return (error); 2463 } 2464 2465 if (tzp) /* Attempt to remove the existing target */ 2466 error = zfs_link_destroy(tdl, tzp, tx, 0, NULL); 2467 2468 if (error == 0) { 2469 error = zfs_link_create(tdl, szp, tx, ZRENAMING); 2470 if (error == 0) { 2471 error = zfs_link_destroy(sdl, szp, tx, ZRENAMING, NULL); 2472 ASSERT(error == 0); 2473 zfs_log_rename(zilog, tx, TX_RENAME, sdzp, 2474 sdl->dl_name, tdzp, tdl->dl_name, szp); 2475 } 2476 } 2477 2478 dmu_tx_commit(tx); 2479 out: 2480 if (zl != NULL) 2481 zfs_rename_unlock(&zl); 2482 2483 zfs_dirent_unlock(sdl); 2484 zfs_dirent_unlock(tdl); 2485 2486 VN_RELE(ZTOV(szp)); 2487 if (tzp) 2488 VN_RELE(ZTOV(tzp)); 2489 2490 ZFS_EXIT(zfsvfs); 2491 return (error); 2492 } 2493 2494 /* 2495 * Insert the indicated symbolic reference entry into the directory. 2496 * 2497 * IN: dvp - Directory to contain new symbolic link. 2498 * link - Name for new symlink entry. 2499 * vap - Attributes of new entry. 2500 * target - Target path of new symlink. 2501 * cr - credentials of caller. 2502 * 2503 * RETURN: 0 if success 2504 * error code if failure 2505 * 2506 * Timestamps: 2507 * dvp - ctime|mtime updated 2508 */ 2509 static int 2510 zfs_symlink(vnode_t *dvp, char *name, vattr_t *vap, char *link, cred_t *cr) 2511 { 2512 znode_t *zp, *dzp = VTOZ(dvp); 2513 zfs_dirlock_t *dl; 2514 dmu_tx_t *tx; 2515 zfsvfs_t *zfsvfs = dzp->z_zfsvfs; 2516 zilog_t *zilog = zfsvfs->z_log; 2517 uint64_t zoid; 2518 int len = strlen(link); 2519 int error; 2520 2521 ASSERT(vap->va_type == VLNK); 2522 2523 ZFS_ENTER(zfsvfs); 2524 top: 2525 if (error = zfs_zaccess(dzp, ACE_ADD_FILE, cr)) { 2526 ZFS_EXIT(zfsvfs); 2527 return (error); 2528 } 2529 2530 if (len > MAXPATHLEN) { 2531 ZFS_EXIT(zfsvfs); 2532 return (ENAMETOOLONG); 2533 } 2534 2535 /* 2536 * Attempt to lock directory; fail if entry already exists. 2537 */ 2538 if (error = zfs_dirent_lock(&dl, dzp, name, &zp, ZNEW)) { 2539 ZFS_EXIT(zfsvfs); 2540 return (error); 2541 } 2542 2543 tx = dmu_tx_create(zfsvfs->z_os); 2544 dmu_tx_hold_write(tx, DMU_NEW_OBJECT, 0, MAX(1, len)); 2545 dmu_tx_hold_bonus(tx, dzp->z_id); 2546 dmu_tx_hold_zap(tx, dzp->z_id, TRUE, name); 2547 if (dzp->z_phys->zp_flags & ZFS_INHERIT_ACE) 2548 dmu_tx_hold_write(tx, DMU_NEW_OBJECT, 0, SPA_MAXBLOCKSIZE); 2549 error = dmu_tx_assign(tx, zfsvfs->z_assign); 2550 if (error) { 2551 zfs_dirent_unlock(dl); 2552 if (error == ERESTART && zfsvfs->z_assign == TXG_NOWAIT) { 2553 dmu_tx_wait(tx); 2554 dmu_tx_abort(tx); 2555 goto top; 2556 } 2557 dmu_tx_abort(tx); 2558 ZFS_EXIT(zfsvfs); 2559 return (error); 2560 } 2561 2562 dmu_buf_will_dirty(dzp->z_dbuf, tx); 2563 2564 /* 2565 * Create a new object for the symlink. 2566 * Put the link content into bonus buffer if it will fit; 2567 * otherwise, store it just like any other file data. 2568 */ 2569 zoid = 0; 2570 if (sizeof (znode_phys_t) + len <= dmu_bonus_max()) { 2571 zfs_mknode(dzp, vap, &zoid, tx, cr, 0, &zp, len); 2572 if (len != 0) 2573 bcopy(link, zp->z_phys + 1, len); 2574 } else { 2575 dmu_buf_t *dbp; 2576 2577 zfs_mknode(dzp, vap, &zoid, tx, cr, 0, &zp, 0); 2578 2579 /* 2580 * Nothing can access the znode yet so no locking needed 2581 * for growing the znode's blocksize. 2582 */ 2583 zfs_grow_blocksize(zp, len, tx); 2584 2585 VERIFY(0 == dmu_buf_hold(zfsvfs->z_os, zoid, 0, FTAG, &dbp)); 2586 dmu_buf_will_dirty(dbp, tx); 2587 2588 ASSERT3U(len, <=, dbp->db_size); 2589 bcopy(link, dbp->db_data, len); 2590 dmu_buf_rele(dbp, FTAG); 2591 } 2592 zp->z_phys->zp_size = len; 2593 2594 /* 2595 * Insert the new object into the directory. 2596 */ 2597 (void) zfs_link_create(dl, zp, tx, ZNEW); 2598 out: 2599 if (error == 0) 2600 zfs_log_symlink(zilog, tx, TX_SYMLINK, dzp, zp, name, link); 2601 2602 dmu_tx_commit(tx); 2603 2604 zfs_dirent_unlock(dl); 2605 2606 VN_RELE(ZTOV(zp)); 2607 2608 ZFS_EXIT(zfsvfs); 2609 return (error); 2610 } 2611 2612 /* 2613 * Return, in the buffer contained in the provided uio structure, 2614 * the symbolic path referred to by vp. 2615 * 2616 * IN: vp - vnode of symbolic link. 2617 * uoip - structure to contain the link path. 2618 * cr - credentials of caller. 2619 * 2620 * OUT: uio - structure to contain the link path. 2621 * 2622 * RETURN: 0 if success 2623 * error code if failure 2624 * 2625 * Timestamps: 2626 * vp - atime updated 2627 */ 2628 /* ARGSUSED */ 2629 static int 2630 zfs_readlink(vnode_t *vp, uio_t *uio, cred_t *cr) 2631 { 2632 znode_t *zp = VTOZ(vp); 2633 zfsvfs_t *zfsvfs = zp->z_zfsvfs; 2634 size_t bufsz; 2635 int error; 2636 2637 ZFS_ENTER(zfsvfs); 2638 2639 bufsz = (size_t)zp->z_phys->zp_size; 2640 if (bufsz + sizeof (znode_phys_t) <= zp->z_dbuf->db_size) { 2641 error = uiomove(zp->z_phys + 1, 2642 MIN((size_t)bufsz, uio->uio_resid), UIO_READ, uio); 2643 } else { 2644 dmu_buf_t *dbp; 2645 error = dmu_buf_hold(zfsvfs->z_os, zp->z_id, 0, FTAG, &dbp); 2646 if (error) { 2647 ZFS_EXIT(zfsvfs); 2648 return (error); 2649 } 2650 error = uiomove(dbp->db_data, 2651 MIN((size_t)bufsz, uio->uio_resid), UIO_READ, uio); 2652 dmu_buf_rele(dbp, FTAG); 2653 } 2654 2655 ZFS_ACCESSTIME_STAMP(zfsvfs, zp); 2656 ZFS_EXIT(zfsvfs); 2657 return (error); 2658 } 2659 2660 /* 2661 * Insert a new entry into directory tdvp referencing svp. 2662 * 2663 * IN: tdvp - Directory to contain new entry. 2664 * svp - vnode of new entry. 2665 * name - name of new entry. 2666 * cr - credentials of caller. 2667 * 2668 * RETURN: 0 if success 2669 * error code if failure 2670 * 2671 * Timestamps: 2672 * tdvp - ctime|mtime updated 2673 * svp - ctime updated 2674 */ 2675 /* ARGSUSED */ 2676 static int 2677 zfs_link(vnode_t *tdvp, vnode_t *svp, char *name, cred_t *cr) 2678 { 2679 znode_t *dzp = VTOZ(tdvp); 2680 znode_t *tzp, *szp; 2681 zfsvfs_t *zfsvfs = dzp->z_zfsvfs; 2682 zilog_t *zilog = zfsvfs->z_log; 2683 zfs_dirlock_t *dl; 2684 dmu_tx_t *tx; 2685 vnode_t *realvp; 2686 int error; 2687 2688 ASSERT(tdvp->v_type == VDIR); 2689 2690 ZFS_ENTER(zfsvfs); 2691 2692 if (VOP_REALVP(svp, &realvp) == 0) 2693 svp = realvp; 2694 2695 if (svp->v_vfsp != tdvp->v_vfsp) { 2696 ZFS_EXIT(zfsvfs); 2697 return (EXDEV); 2698 } 2699 2700 szp = VTOZ(svp); 2701 top: 2702 /* 2703 * We do not support links between attributes and non-attributes 2704 * because of the potential security risk of creating links 2705 * into "normal" file space in order to circumvent restrictions 2706 * imposed in attribute space. 2707 */ 2708 if ((szp->z_phys->zp_flags & ZFS_XATTR) != 2709 (dzp->z_phys->zp_flags & ZFS_XATTR)) { 2710 ZFS_EXIT(zfsvfs); 2711 return (EINVAL); 2712 } 2713 2714 /* 2715 * POSIX dictates that we return EPERM here. 2716 * Better choices include ENOTSUP or EISDIR. 2717 */ 2718 if (svp->v_type == VDIR) { 2719 ZFS_EXIT(zfsvfs); 2720 return (EPERM); 2721 } 2722 2723 if ((uid_t)szp->z_phys->zp_uid != crgetuid(cr) && 2724 secpolicy_basic_link(cr) != 0) { 2725 ZFS_EXIT(zfsvfs); 2726 return (EPERM); 2727 } 2728 2729 if (error = zfs_zaccess(dzp, ACE_ADD_FILE, cr)) { 2730 ZFS_EXIT(zfsvfs); 2731 return (error); 2732 } 2733 2734 /* 2735 * Attempt to lock directory; fail if entry already exists. 2736 */ 2737 if (error = zfs_dirent_lock(&dl, dzp, name, &tzp, ZNEW)) { 2738 ZFS_EXIT(zfsvfs); 2739 return (error); 2740 } 2741 2742 tx = dmu_tx_create(zfsvfs->z_os); 2743 dmu_tx_hold_bonus(tx, szp->z_id); 2744 dmu_tx_hold_zap(tx, dzp->z_id, TRUE, name); 2745 error = dmu_tx_assign(tx, zfsvfs->z_assign); 2746 if (error) { 2747 zfs_dirent_unlock(dl); 2748 if (error == ERESTART && zfsvfs->z_assign == TXG_NOWAIT) { 2749 dmu_tx_wait(tx); 2750 dmu_tx_abort(tx); 2751 goto top; 2752 } 2753 dmu_tx_abort(tx); 2754 ZFS_EXIT(zfsvfs); 2755 return (error); 2756 } 2757 2758 error = zfs_link_create(dl, szp, tx, 0); 2759 2760 if (error == 0) 2761 zfs_log_link(zilog, tx, TX_LINK, dzp, szp, name); 2762 2763 dmu_tx_commit(tx); 2764 2765 zfs_dirent_unlock(dl); 2766 2767 ZFS_EXIT(zfsvfs); 2768 return (error); 2769 } 2770 2771 /* 2772 * zfs_null_putapage() is used when the file system has been force 2773 * unmounted. It just drops the pages. 2774 */ 2775 /* ARGSUSED */ 2776 static int 2777 zfs_null_putapage(vnode_t *vp, page_t *pp, u_offset_t *offp, 2778 size_t *lenp, int flags, cred_t *cr) 2779 { 2780 pvn_write_done(pp, B_INVAL|B_FORCE|B_ERROR); 2781 return (0); 2782 } 2783 2784 /* 2785 * Push a page out to disk, klustering if possible. 2786 * 2787 * IN: vp - file to push page to. 2788 * pp - page to push. 2789 * flags - additional flags. 2790 * cr - credentials of caller. 2791 * 2792 * OUT: offp - start of range pushed. 2793 * lenp - len of range pushed. 2794 * 2795 * RETURN: 0 if success 2796 * error code if failure 2797 * 2798 * NOTE: callers must have locked the page to be pushed. On 2799 * exit, the page (and all other pages in the kluster) must be 2800 * unlocked. 2801 */ 2802 /* ARGSUSED */ 2803 static int 2804 zfs_putapage(vnode_t *vp, page_t *pp, u_offset_t *offp, 2805 size_t *lenp, int flags, cred_t *cr) 2806 { 2807 znode_t *zp = VTOZ(vp); 2808 zfsvfs_t *zfsvfs = zp->z_zfsvfs; 2809 zilog_t *zilog = zfsvfs->z_log; 2810 dmu_tx_t *tx; 2811 rl_t *rl; 2812 u_offset_t off, koff; 2813 size_t len, klen; 2814 uint64_t filesz; 2815 int err; 2816 2817 filesz = zp->z_phys->zp_size; 2818 off = pp->p_offset; 2819 len = PAGESIZE; 2820 /* 2821 * If our blocksize is bigger than the page size, try to kluster 2822 * muiltiple pages so that we write a full block (thus avoiding 2823 * a read-modify-write). 2824 */ 2825 if (off < filesz && zp->z_blksz > PAGESIZE) { 2826 if (!ISP2(zp->z_blksz)) { 2827 /* Only one block in the file. */ 2828 klen = P2ROUNDUP((ulong_t)zp->z_blksz, PAGESIZE); 2829 koff = 0; 2830 } else { 2831 klen = zp->z_blksz; 2832 koff = P2ALIGN(off, (u_offset_t)klen); 2833 } 2834 ASSERT(koff <= filesz); 2835 if (koff + klen > filesz) 2836 klen = P2ROUNDUP(filesz - koff, (uint64_t)PAGESIZE); 2837 pp = pvn_write_kluster(vp, pp, &off, &len, koff, klen, flags); 2838 } 2839 ASSERT3U(btop(len), ==, btopr(len)); 2840 top: 2841 rl = zfs_range_lock(zp, off, len, RL_WRITER); 2842 /* 2843 * Can't push pages past end-of-file. 2844 */ 2845 filesz = zp->z_phys->zp_size; 2846 if (off >= filesz) { 2847 /* ignore all pages */ 2848 err = 0; 2849 goto out; 2850 } else if (off + len > filesz) { 2851 int npages = btopr(filesz - off); 2852 page_t *trunc; 2853 2854 page_list_break(&pp, &trunc, npages); 2855 /* ignore pages past end of file */ 2856 if (trunc) 2857 pvn_write_done(trunc, flags); 2858 len = filesz - off; 2859 } 2860 2861 tx = dmu_tx_create(zfsvfs->z_os); 2862 dmu_tx_hold_write(tx, zp->z_id, off, len); 2863 dmu_tx_hold_bonus(tx, zp->z_id); 2864 err = dmu_tx_assign(tx, zfsvfs->z_assign); 2865 if (err != 0) { 2866 if (err == ERESTART && zfsvfs->z_assign == TXG_NOWAIT) { 2867 zfs_range_unlock(rl); 2868 dmu_tx_wait(tx); 2869 dmu_tx_abort(tx); 2870 err = 0; 2871 goto top; 2872 } 2873 dmu_tx_abort(tx); 2874 goto out; 2875 } 2876 2877 if (zp->z_blksz <= PAGESIZE) { 2878 caddr_t va = ppmapin(pp, PROT_READ, (caddr_t)-1); 2879 ASSERT3U(len, <=, PAGESIZE); 2880 dmu_write(zfsvfs->z_os, zp->z_id, off, len, va, tx); 2881 ppmapout(va); 2882 } else { 2883 err = dmu_write_pages(zfsvfs->z_os, zp->z_id, off, len, pp, tx); 2884 } 2885 2886 if (err == 0) { 2887 zfs_time_stamper(zp, CONTENT_MODIFIED, tx); 2888 zfs_log_write(zilog, tx, TX_WRITE, zp, off, len, 0); 2889 dmu_tx_commit(tx); 2890 } 2891 2892 out: 2893 zfs_range_unlock(rl); 2894 pvn_write_done(pp, (err ? B_ERROR : 0) | flags); 2895 if (offp) 2896 *offp = off; 2897 if (lenp) 2898 *lenp = len; 2899 2900 return (err); 2901 } 2902 2903 /* 2904 * Copy the portion of the file indicated from pages into the file. 2905 * The pages are stored in a page list attached to the files vnode. 2906 * 2907 * IN: vp - vnode of file to push page data to. 2908 * off - position in file to put data. 2909 * len - amount of data to write. 2910 * flags - flags to control the operation. 2911 * cr - credentials of caller. 2912 * 2913 * RETURN: 0 if success 2914 * error code if failure 2915 * 2916 * Timestamps: 2917 * vp - ctime|mtime updated 2918 */ 2919 static int 2920 zfs_putpage(vnode_t *vp, offset_t off, size_t len, int flags, cred_t *cr) 2921 { 2922 znode_t *zp = VTOZ(vp); 2923 zfsvfs_t *zfsvfs = zp->z_zfsvfs; 2924 page_t *pp; 2925 size_t io_len; 2926 u_offset_t io_off; 2927 uint64_t filesz; 2928 int error = 0; 2929 2930 ZFS_ENTER(zfsvfs); 2931 2932 ASSERT(zp->z_dbuf_held && zp->z_phys); 2933 2934 if (len == 0) { 2935 /* 2936 * Search the entire vp list for pages >= off. 2937 */ 2938 error = pvn_vplist_dirty(vp, (u_offset_t)off, zfs_putapage, 2939 flags, cr); 2940 goto out; 2941 } 2942 2943 filesz = zp->z_phys->zp_size; /* get consistent copy of zp_size */ 2944 if (off > filesz) { 2945 /* past end of file */ 2946 ZFS_EXIT(zfsvfs); 2947 return (0); 2948 } 2949 2950 len = MIN(len, filesz - off); 2951 2952 for (io_off = off; io_off < off + len; io_off += io_len) { 2953 if ((flags & B_INVAL) || ((flags & B_ASYNC) == 0)) { 2954 pp = page_lookup(vp, io_off, 2955 (flags & (B_INVAL | B_FREE)) ? SE_EXCL : SE_SHARED); 2956 } else { 2957 pp = page_lookup_nowait(vp, io_off, 2958 (flags & B_FREE) ? SE_EXCL : SE_SHARED); 2959 } 2960 2961 if (pp != NULL && pvn_getdirty(pp, flags)) { 2962 int err; 2963 2964 /* 2965 * Found a dirty page to push 2966 */ 2967 err = zfs_putapage(vp, pp, &io_off, &io_len, flags, cr); 2968 if (err) 2969 error = err; 2970 } else { 2971 io_len = PAGESIZE; 2972 } 2973 } 2974 out: 2975 if ((flags & B_ASYNC) == 0) 2976 zil_commit(zfsvfs->z_log, UINT64_MAX, zp->z_id); 2977 ZFS_EXIT(zfsvfs); 2978 return (error); 2979 } 2980 2981 void 2982 zfs_inactive(vnode_t *vp, cred_t *cr) 2983 { 2984 znode_t *zp = VTOZ(vp); 2985 zfsvfs_t *zfsvfs = zp->z_zfsvfs; 2986 int error; 2987 2988 rw_enter(&zfsvfs->z_um_lock, RW_READER); 2989 if (zfsvfs->z_unmounted2) { 2990 ASSERT(zp->z_dbuf_held == 0); 2991 2992 if (vn_has_cached_data(vp)) { 2993 (void) pvn_vplist_dirty(vp, 0, zfs_null_putapage, 2994 B_INVAL, cr); 2995 } 2996 2997 mutex_enter(&zp->z_lock); 2998 vp->v_count = 0; /* count arrives as 1 */ 2999 if (zp->z_dbuf == NULL) { 3000 mutex_exit(&zp->z_lock); 3001 zfs_znode_free(zp); 3002 } else { 3003 mutex_exit(&zp->z_lock); 3004 } 3005 rw_exit(&zfsvfs->z_um_lock); 3006 VFS_RELE(zfsvfs->z_vfs); 3007 return; 3008 } 3009 3010 /* 3011 * Attempt to push any data in the page cache. If this fails 3012 * we will get kicked out later in zfs_zinactive(). 3013 */ 3014 if (vn_has_cached_data(vp)) { 3015 (void) pvn_vplist_dirty(vp, 0, zfs_putapage, B_INVAL|B_ASYNC, 3016 cr); 3017 } 3018 3019 if (zp->z_atime_dirty && zp->z_unlinked == 0) { 3020 dmu_tx_t *tx = dmu_tx_create(zfsvfs->z_os); 3021 3022 dmu_tx_hold_bonus(tx, zp->z_id); 3023 error = dmu_tx_assign(tx, TXG_WAIT); 3024 if (error) { 3025 dmu_tx_abort(tx); 3026 } else { 3027 dmu_buf_will_dirty(zp->z_dbuf, tx); 3028 mutex_enter(&zp->z_lock); 3029 zp->z_atime_dirty = 0; 3030 mutex_exit(&zp->z_lock); 3031 dmu_tx_commit(tx); 3032 } 3033 } 3034 3035 zfs_zinactive(zp); 3036 rw_exit(&zfsvfs->z_um_lock); 3037 } 3038 3039 /* 3040 * Bounds-check the seek operation. 3041 * 3042 * IN: vp - vnode seeking within 3043 * ooff - old file offset 3044 * noffp - pointer to new file offset 3045 * 3046 * RETURN: 0 if success 3047 * EINVAL if new offset invalid 3048 */ 3049 /* ARGSUSED */ 3050 static int 3051 zfs_seek(vnode_t *vp, offset_t ooff, offset_t *noffp) 3052 { 3053 if (vp->v_type == VDIR) 3054 return (0); 3055 return ((*noffp < 0 || *noffp > MAXOFFSET_T) ? EINVAL : 0); 3056 } 3057 3058 /* 3059 * Pre-filter the generic locking function to trap attempts to place 3060 * a mandatory lock on a memory mapped file. 3061 */ 3062 static int 3063 zfs_frlock(vnode_t *vp, int cmd, flock64_t *bfp, int flag, offset_t offset, 3064 flk_callback_t *flk_cbp, cred_t *cr) 3065 { 3066 znode_t *zp = VTOZ(vp); 3067 zfsvfs_t *zfsvfs = zp->z_zfsvfs; 3068 int error; 3069 3070 ZFS_ENTER(zfsvfs); 3071 3072 /* 3073 * We are following the UFS semantics with respect to mapcnt 3074 * here: If we see that the file is mapped already, then we will 3075 * return an error, but we don't worry about races between this 3076 * function and zfs_map(). 3077 */ 3078 if (zp->z_mapcnt > 0 && MANDMODE((mode_t)zp->z_phys->zp_mode)) { 3079 ZFS_EXIT(zfsvfs); 3080 return (EAGAIN); 3081 } 3082 error = fs_frlock(vp, cmd, bfp, flag, offset, flk_cbp, cr); 3083 ZFS_EXIT(zfsvfs); 3084 return (error); 3085 } 3086 3087 /* 3088 * If we can't find a page in the cache, we will create a new page 3089 * and fill it with file data. For efficiency, we may try to fill 3090 * multiple pages at once (klustering). 3091 */ 3092 static int 3093 zfs_fillpage(vnode_t *vp, u_offset_t off, struct seg *seg, 3094 caddr_t addr, page_t *pl[], size_t plsz, enum seg_rw rw) 3095 { 3096 znode_t *zp = VTOZ(vp); 3097 page_t *pp, *cur_pp; 3098 objset_t *os = zp->z_zfsvfs->z_os; 3099 caddr_t va; 3100 u_offset_t io_off, total; 3101 uint64_t oid = zp->z_id; 3102 size_t io_len; 3103 uint64_t filesz; 3104 int err; 3105 3106 /* 3107 * If we are only asking for a single page don't bother klustering. 3108 */ 3109 filesz = zp->z_phys->zp_size; /* get consistent copy of zp_size */ 3110 if (off >= filesz) 3111 return (EFAULT); 3112 if (plsz == PAGESIZE || zp->z_blksz <= PAGESIZE) { 3113 io_off = off; 3114 io_len = PAGESIZE; 3115 pp = page_create_va(vp, io_off, io_len, PG_WAIT, seg, addr); 3116 } else { 3117 /* 3118 * Try to fill a kluster of pages (a blocks worth). 3119 */ 3120 size_t klen; 3121 u_offset_t koff; 3122 3123 if (!ISP2(zp->z_blksz)) { 3124 /* Only one block in the file. */ 3125 klen = P2ROUNDUP((ulong_t)zp->z_blksz, PAGESIZE); 3126 koff = 0; 3127 } else { 3128 /* 3129 * It would be ideal to align our offset to the 3130 * blocksize but doing so has resulted in some 3131 * strange application crashes. For now, we 3132 * leave the offset as is and only adjust the 3133 * length if we are off the end of the file. 3134 */ 3135 koff = off; 3136 klen = plsz; 3137 } 3138 ASSERT(koff <= filesz); 3139 if (koff + klen > filesz) 3140 klen = P2ROUNDUP(filesz, (uint64_t)PAGESIZE) - koff; 3141 ASSERT3U(off, >=, koff); 3142 ASSERT3U(off, <, koff + klen); 3143 pp = pvn_read_kluster(vp, off, seg, addr, &io_off, 3144 &io_len, koff, klen, 0); 3145 } 3146 if (pp == NULL) { 3147 /* 3148 * Some other thread entered the page before us. 3149 * Return to zfs_getpage to retry the lookup. 3150 */ 3151 *pl = NULL; 3152 return (0); 3153 } 3154 3155 /* 3156 * Fill the pages in the kluster. 3157 */ 3158 cur_pp = pp; 3159 for (total = io_off + io_len; io_off < total; io_off += PAGESIZE) { 3160 ASSERT3U(io_off, ==, cur_pp->p_offset); 3161 va = ppmapin(cur_pp, PROT_READ | PROT_WRITE, (caddr_t)-1); 3162 err = dmu_read(os, oid, io_off, PAGESIZE, va); 3163 ppmapout(va); 3164 if (err) { 3165 /* On error, toss the entire kluster */ 3166 pvn_read_done(pp, B_ERROR); 3167 return (err); 3168 } 3169 cur_pp = cur_pp->p_next; 3170 } 3171 out: 3172 /* 3173 * Fill in the page list array from the kluster. If 3174 * there are too many pages in the kluster, return 3175 * as many pages as possible starting from the desired 3176 * offset `off'. 3177 * NOTE: the page list will always be null terminated. 3178 */ 3179 pvn_plist_init(pp, pl, plsz, off, io_len, rw); 3180 3181 return (0); 3182 } 3183 3184 /* 3185 * Return pointers to the pages for the file region [off, off + len] 3186 * in the pl array. If plsz is greater than len, this function may 3187 * also return page pointers from before or after the specified 3188 * region (i.e. some region [off', off' + plsz]). These additional 3189 * pages are only returned if they are already in the cache, or were 3190 * created as part of a klustered read. 3191 * 3192 * IN: vp - vnode of file to get data from. 3193 * off - position in file to get data from. 3194 * len - amount of data to retrieve. 3195 * plsz - length of provided page list. 3196 * seg - segment to obtain pages for. 3197 * addr - virtual address of fault. 3198 * rw - mode of created pages. 3199 * cr - credentials of caller. 3200 * 3201 * OUT: protp - protection mode of created pages. 3202 * pl - list of pages created. 3203 * 3204 * RETURN: 0 if success 3205 * error code if failure 3206 * 3207 * Timestamps: 3208 * vp - atime updated 3209 */ 3210 /* ARGSUSED */ 3211 static int 3212 zfs_getpage(vnode_t *vp, offset_t off, size_t len, uint_t *protp, 3213 page_t *pl[], size_t plsz, struct seg *seg, caddr_t addr, 3214 enum seg_rw rw, cred_t *cr) 3215 { 3216 znode_t *zp = VTOZ(vp); 3217 zfsvfs_t *zfsvfs = zp->z_zfsvfs; 3218 page_t *pp, **pl0 = pl; 3219 int need_unlock = 0, err = 0; 3220 offset_t orig_off; 3221 3222 ZFS_ENTER(zfsvfs); 3223 3224 if (protp) 3225 *protp = PROT_ALL; 3226 3227 ASSERT(zp->z_dbuf_held && zp->z_phys); 3228 3229 /* no faultahead (for now) */ 3230 if (pl == NULL) { 3231 ZFS_EXIT(zfsvfs); 3232 return (0); 3233 } 3234 3235 /* can't fault past EOF */ 3236 if (off >= zp->z_phys->zp_size) { 3237 ZFS_EXIT(zfsvfs); 3238 return (EFAULT); 3239 } 3240 orig_off = off; 3241 3242 /* 3243 * If we already own the lock, then we must be page faulting 3244 * in the middle of a write to this file (i.e., we are writing 3245 * to this file using data from a mapped region of the file). 3246 */ 3247 if (rw_owner(&zp->z_map_lock) != curthread) { 3248 rw_enter(&zp->z_map_lock, RW_WRITER); 3249 need_unlock = TRUE; 3250 } 3251 3252 /* 3253 * Loop through the requested range [off, off + len] looking 3254 * for pages. If we don't find a page, we will need to create 3255 * a new page and fill it with data from the file. 3256 */ 3257 while (len > 0) { 3258 if (plsz < PAGESIZE) 3259 break; 3260 if (pp = page_lookup(vp, off, SE_SHARED)) { 3261 *pl++ = pp; 3262 off += PAGESIZE; 3263 addr += PAGESIZE; 3264 len -= PAGESIZE; 3265 plsz -= PAGESIZE; 3266 } else { 3267 err = zfs_fillpage(vp, off, seg, addr, pl, plsz, rw); 3268 if (err) 3269 goto out; 3270 /* 3271 * klustering may have changed our region 3272 * to be block aligned. 3273 */ 3274 if (((pp = *pl) != 0) && (off != pp->p_offset)) { 3275 int delta = off - pp->p_offset; 3276 len += delta; 3277 off -= delta; 3278 addr -= delta; 3279 } 3280 while (*pl) { 3281 pl++; 3282 off += PAGESIZE; 3283 addr += PAGESIZE; 3284 plsz -= PAGESIZE; 3285 if (len > PAGESIZE) 3286 len -= PAGESIZE; 3287 else 3288 len = 0; 3289 } 3290 } 3291 } 3292 3293 /* 3294 * Fill out the page array with any pages already in the cache. 3295 */ 3296 while (plsz > 0) { 3297 pp = page_lookup_nowait(vp, off, SE_SHARED); 3298 if (pp == NULL) 3299 break; 3300 *pl++ = pp; 3301 off += PAGESIZE; 3302 plsz -= PAGESIZE; 3303 } 3304 3305 ZFS_ACCESSTIME_STAMP(zfsvfs, zp); 3306 out: 3307 /* 3308 * We can't grab the range lock for the page as reader which would 3309 * stop truncation as this leads to deadlock. So we need to recheck 3310 * the file size. 3311 */ 3312 if (orig_off >= zp->z_phys->zp_size) 3313 err = EFAULT; 3314 if (err) { 3315 /* 3316 * Release any pages we have previously locked. 3317 */ 3318 while (pl > pl0) 3319 page_unlock(*--pl); 3320 } 3321 3322 *pl = NULL; 3323 3324 if (need_unlock) 3325 rw_exit(&zp->z_map_lock); 3326 3327 ZFS_EXIT(zfsvfs); 3328 return (err); 3329 } 3330 3331 /* 3332 * Request a memory map for a section of a file. This code interacts 3333 * with common code and the VM system as follows: 3334 * 3335 * common code calls mmap(), which ends up in smmap_common() 3336 * 3337 * this calls VOP_MAP(), which takes you into (say) zfs 3338 * 3339 * zfs_map() calls as_map(), passing segvn_create() as the callback 3340 * 3341 * segvn_create() creates the new segment and calls VOP_ADDMAP() 3342 * 3343 * zfs_addmap() updates z_mapcnt 3344 */ 3345 static int 3346 zfs_map(vnode_t *vp, offset_t off, struct as *as, caddr_t *addrp, 3347 size_t len, uchar_t prot, uchar_t maxprot, uint_t flags, cred_t *cr) 3348 { 3349 znode_t *zp = VTOZ(vp); 3350 zfsvfs_t *zfsvfs = zp->z_zfsvfs; 3351 segvn_crargs_t vn_a; 3352 int error; 3353 3354 ZFS_ENTER(zfsvfs); 3355 3356 if (vp->v_flag & VNOMAP) { 3357 ZFS_EXIT(zfsvfs); 3358 return (ENOSYS); 3359 } 3360 3361 if (off < 0 || len > MAXOFFSET_T - off) { 3362 ZFS_EXIT(zfsvfs); 3363 return (ENXIO); 3364 } 3365 3366 if (vp->v_type != VREG) { 3367 ZFS_EXIT(zfsvfs); 3368 return (ENODEV); 3369 } 3370 3371 /* 3372 * If file is locked, disallow mapping. 3373 */ 3374 if (MANDMODE((mode_t)zp->z_phys->zp_mode) && vn_has_flocks(vp)) { 3375 ZFS_EXIT(zfsvfs); 3376 return (EAGAIN); 3377 } 3378 3379 as_rangelock(as); 3380 if ((flags & MAP_FIXED) == 0) { 3381 map_addr(addrp, len, off, 1, flags); 3382 if (*addrp == NULL) { 3383 as_rangeunlock(as); 3384 ZFS_EXIT(zfsvfs); 3385 return (ENOMEM); 3386 } 3387 } else { 3388 /* 3389 * User specified address - blow away any previous mappings 3390 */ 3391 (void) as_unmap(as, *addrp, len); 3392 } 3393 3394 vn_a.vp = vp; 3395 vn_a.offset = (u_offset_t)off; 3396 vn_a.type = flags & MAP_TYPE; 3397 vn_a.prot = prot; 3398 vn_a.maxprot = maxprot; 3399 vn_a.cred = cr; 3400 vn_a.amp = NULL; 3401 vn_a.flags = flags & ~MAP_TYPE; 3402 vn_a.szc = 0; 3403 vn_a.lgrp_mem_policy_flags = 0; 3404 3405 error = as_map(as, *addrp, len, segvn_create, &vn_a); 3406 3407 as_rangeunlock(as); 3408 ZFS_EXIT(zfsvfs); 3409 return (error); 3410 } 3411 3412 /* ARGSUSED */ 3413 static int 3414 zfs_addmap(vnode_t *vp, offset_t off, struct as *as, caddr_t addr, 3415 size_t len, uchar_t prot, uchar_t maxprot, uint_t flags, cred_t *cr) 3416 { 3417 uint64_t pages = btopr(len); 3418 3419 atomic_add_64(&VTOZ(vp)->z_mapcnt, pages); 3420 return (0); 3421 } 3422 3423 /* 3424 * The reason we push dirty pages as part of zfs_delmap() is so that we get a 3425 * more accurate mtime for the associated file. Since we don't have a way of 3426 * detecting when the data was actually modified, we have to resort to 3427 * heuristics. If an explicit msync() is done, then we mark the mtime when the 3428 * last page is pushed. The problem occurs when the msync() call is omitted, 3429 * which by far the most common case: 3430 * 3431 * open() 3432 * mmap() 3433 * <modify memory> 3434 * munmap() 3435 * close() 3436 * <time lapse> 3437 * putpage() via fsflush 3438 * 3439 * If we wait until fsflush to come along, we can have a modification time that 3440 * is some arbitrary point in the future. In order to prevent this in the 3441 * common case, we flush pages whenever a (MAP_SHARED, PROT_WRITE) mapping is 3442 * torn down. 3443 */ 3444 /* ARGSUSED */ 3445 static int 3446 zfs_delmap(vnode_t *vp, offset_t off, struct as *as, caddr_t addr, 3447 size_t len, uint_t prot, uint_t maxprot, uint_t flags, cred_t *cr) 3448 { 3449 uint64_t pages = btopr(len); 3450 3451 ASSERT3U(VTOZ(vp)->z_mapcnt, >=, pages); 3452 atomic_add_64(&VTOZ(vp)->z_mapcnt, -pages); 3453 3454 if ((flags & MAP_SHARED) && (prot & PROT_WRITE) && 3455 vn_has_cached_data(vp)) 3456 (void) VOP_PUTPAGE(vp, off, len, B_ASYNC, cr); 3457 3458 return (0); 3459 } 3460 3461 /* 3462 * Free or allocate space in a file. Currently, this function only 3463 * supports the `F_FREESP' command. However, this command is somewhat 3464 * misnamed, as its functionality includes the ability to allocate as 3465 * well as free space. 3466 * 3467 * IN: vp - vnode of file to free data in. 3468 * cmd - action to take (only F_FREESP supported). 3469 * bfp - section of file to free/alloc. 3470 * flag - current file open mode flags. 3471 * offset - current file offset. 3472 * cr - credentials of caller [UNUSED]. 3473 * 3474 * RETURN: 0 if success 3475 * error code if failure 3476 * 3477 * Timestamps: 3478 * vp - ctime|mtime updated 3479 */ 3480 /* ARGSUSED */ 3481 static int 3482 zfs_space(vnode_t *vp, int cmd, flock64_t *bfp, int flag, 3483 offset_t offset, cred_t *cr, caller_context_t *ct) 3484 { 3485 znode_t *zp = VTOZ(vp); 3486 zfsvfs_t *zfsvfs = zp->z_zfsvfs; 3487 uint64_t off, len; 3488 int error; 3489 3490 ZFS_ENTER(zfsvfs); 3491 3492 top: 3493 if (cmd != F_FREESP) { 3494 ZFS_EXIT(zfsvfs); 3495 return (EINVAL); 3496 } 3497 3498 if (error = convoff(vp, bfp, 0, offset)) { 3499 ZFS_EXIT(zfsvfs); 3500 return (error); 3501 } 3502 3503 if (bfp->l_len < 0) { 3504 ZFS_EXIT(zfsvfs); 3505 return (EINVAL); 3506 } 3507 3508 off = bfp->l_start; 3509 len = bfp->l_len; /* 0 means from off to end of file */ 3510 3511 do { 3512 error = zfs_freesp(zp, off, len, flag, TRUE); 3513 /* NB: we already did dmu_tx_wait() if necessary */ 3514 } while (error == ERESTART && zfsvfs->z_assign == TXG_NOWAIT); 3515 3516 ZFS_EXIT(zfsvfs); 3517 return (error); 3518 } 3519 3520 static int 3521 zfs_fid(vnode_t *vp, fid_t *fidp) 3522 { 3523 znode_t *zp = VTOZ(vp); 3524 zfsvfs_t *zfsvfs = zp->z_zfsvfs; 3525 uint32_t gen = (uint32_t)zp->z_phys->zp_gen; 3526 uint64_t object = zp->z_id; 3527 zfid_short_t *zfid; 3528 int size, i; 3529 3530 ZFS_ENTER(zfsvfs); 3531 3532 size = (zfsvfs->z_parent != zfsvfs) ? LONG_FID_LEN : SHORT_FID_LEN; 3533 if (fidp->fid_len < size) { 3534 fidp->fid_len = size; 3535 ZFS_EXIT(zfsvfs); 3536 return (ENOSPC); 3537 } 3538 3539 zfid = (zfid_short_t *)fidp; 3540 3541 zfid->zf_len = size; 3542 3543 for (i = 0; i < sizeof (zfid->zf_object); i++) 3544 zfid->zf_object[i] = (uint8_t)(object >> (8 * i)); 3545 3546 /* Must have a non-zero generation number to distinguish from .zfs */ 3547 if (gen == 0) 3548 gen = 1; 3549 for (i = 0; i < sizeof (zfid->zf_gen); i++) 3550 zfid->zf_gen[i] = (uint8_t)(gen >> (8 * i)); 3551 3552 if (size == LONG_FID_LEN) { 3553 uint64_t objsetid = dmu_objset_id(zfsvfs->z_os); 3554 zfid_long_t *zlfid; 3555 3556 zlfid = (zfid_long_t *)fidp; 3557 3558 for (i = 0; i < sizeof (zlfid->zf_setid); i++) 3559 zlfid->zf_setid[i] = (uint8_t)(objsetid >> (8 * i)); 3560 3561 /* XXX - this should be the generation number for the objset */ 3562 for (i = 0; i < sizeof (zlfid->zf_setgen); i++) 3563 zlfid->zf_setgen[i] = 0; 3564 } 3565 3566 ZFS_EXIT(zfsvfs); 3567 return (0); 3568 } 3569 3570 static int 3571 zfs_pathconf(vnode_t *vp, int cmd, ulong_t *valp, cred_t *cr) 3572 { 3573 znode_t *zp, *xzp; 3574 zfsvfs_t *zfsvfs; 3575 zfs_dirlock_t *dl; 3576 int error; 3577 3578 switch (cmd) { 3579 case _PC_LINK_MAX: 3580 *valp = ULONG_MAX; 3581 return (0); 3582 3583 case _PC_FILESIZEBITS: 3584 *valp = 64; 3585 return (0); 3586 3587 case _PC_XATTR_EXISTS: 3588 zp = VTOZ(vp); 3589 zfsvfs = zp->z_zfsvfs; 3590 ZFS_ENTER(zfsvfs); 3591 *valp = 0; 3592 error = zfs_dirent_lock(&dl, zp, "", &xzp, 3593 ZXATTR | ZEXISTS | ZSHARED); 3594 if (error == 0) { 3595 zfs_dirent_unlock(dl); 3596 if (!zfs_dirempty(xzp)) 3597 *valp = 1; 3598 VN_RELE(ZTOV(xzp)); 3599 } else if (error == ENOENT) { 3600 /* 3601 * If there aren't extended attributes, it's the 3602 * same as having zero of them. 3603 */ 3604 error = 0; 3605 } 3606 ZFS_EXIT(zfsvfs); 3607 return (error); 3608 3609 case _PC_ACL_ENABLED: 3610 *valp = _ACL_ACE_ENABLED; 3611 return (0); 3612 3613 case _PC_MIN_HOLE_SIZE: 3614 *valp = (ulong_t)SPA_MINBLOCKSIZE; 3615 return (0); 3616 3617 default: 3618 return (fs_pathconf(vp, cmd, valp, cr)); 3619 } 3620 } 3621 3622 /*ARGSUSED*/ 3623 static int 3624 zfs_getsecattr(vnode_t *vp, vsecattr_t *vsecp, int flag, cred_t *cr) 3625 { 3626 znode_t *zp = VTOZ(vp); 3627 zfsvfs_t *zfsvfs = zp->z_zfsvfs; 3628 int error; 3629 3630 ZFS_ENTER(zfsvfs); 3631 error = zfs_getacl(zp, vsecp, cr); 3632 ZFS_EXIT(zfsvfs); 3633 3634 return (error); 3635 } 3636 3637 /*ARGSUSED*/ 3638 static int 3639 zfs_setsecattr(vnode_t *vp, vsecattr_t *vsecp, int flag, cred_t *cr) 3640 { 3641 znode_t *zp = VTOZ(vp); 3642 zfsvfs_t *zfsvfs = zp->z_zfsvfs; 3643 int error; 3644 3645 ZFS_ENTER(zfsvfs); 3646 error = zfs_setacl(zp, vsecp, cr); 3647 ZFS_EXIT(zfsvfs); 3648 return (error); 3649 } 3650 3651 /* 3652 * Predeclare these here so that the compiler assumes that 3653 * this is an "old style" function declaration that does 3654 * not include arguments => we won't get type mismatch errors 3655 * in the initializations that follow. 3656 */ 3657 static int zfs_inval(); 3658 static int zfs_isdir(); 3659 3660 static int 3661 zfs_inval() 3662 { 3663 return (EINVAL); 3664 } 3665 3666 static int 3667 zfs_isdir() 3668 { 3669 return (EISDIR); 3670 } 3671 /* 3672 * Directory vnode operations template 3673 */ 3674 vnodeops_t *zfs_dvnodeops; 3675 const fs_operation_def_t zfs_dvnodeops_template[] = { 3676 VOPNAME_OPEN, { .vop_open = zfs_open }, 3677 VOPNAME_CLOSE, { .vop_close = zfs_close }, 3678 VOPNAME_READ, { .error = zfs_isdir }, 3679 VOPNAME_WRITE, { .error = zfs_isdir }, 3680 VOPNAME_IOCTL, { .vop_ioctl = zfs_ioctl }, 3681 VOPNAME_GETATTR, { .vop_getattr = zfs_getattr }, 3682 VOPNAME_SETATTR, { .vop_setattr = zfs_setattr }, 3683 VOPNAME_ACCESS, { .vop_access = zfs_access }, 3684 VOPNAME_LOOKUP, { .vop_lookup = zfs_lookup }, 3685 VOPNAME_CREATE, { .vop_create = zfs_create }, 3686 VOPNAME_REMOVE, { .vop_remove = zfs_remove }, 3687 VOPNAME_LINK, { .vop_link = zfs_link }, 3688 VOPNAME_RENAME, { .vop_rename = zfs_rename }, 3689 VOPNAME_MKDIR, { .vop_mkdir = zfs_mkdir }, 3690 VOPNAME_RMDIR, { .vop_rmdir = zfs_rmdir }, 3691 VOPNAME_READDIR, { .vop_readdir = zfs_readdir }, 3692 VOPNAME_SYMLINK, { .vop_symlink = zfs_symlink }, 3693 VOPNAME_FSYNC, { .vop_fsync = zfs_fsync }, 3694 VOPNAME_INACTIVE, { .vop_inactive = zfs_inactive }, 3695 VOPNAME_FID, { .vop_fid = zfs_fid }, 3696 VOPNAME_SEEK, { .vop_seek = zfs_seek }, 3697 VOPNAME_PATHCONF, { .vop_pathconf = zfs_pathconf }, 3698 VOPNAME_GETSECATTR, { .vop_getsecattr = zfs_getsecattr }, 3699 VOPNAME_SETSECATTR, { .vop_setsecattr = zfs_setsecattr }, 3700 NULL, NULL 3701 }; 3702 3703 /* 3704 * Regular file vnode operations template 3705 */ 3706 vnodeops_t *zfs_fvnodeops; 3707 const fs_operation_def_t zfs_fvnodeops_template[] = { 3708 VOPNAME_OPEN, { .vop_open = zfs_open }, 3709 VOPNAME_CLOSE, { .vop_close = zfs_close }, 3710 VOPNAME_READ, { .vop_read = zfs_read }, 3711 VOPNAME_WRITE, { .vop_write = zfs_write }, 3712 VOPNAME_IOCTL, { .vop_ioctl = zfs_ioctl }, 3713 VOPNAME_GETATTR, { .vop_getattr = zfs_getattr }, 3714 VOPNAME_SETATTR, { .vop_setattr = zfs_setattr }, 3715 VOPNAME_ACCESS, { .vop_access = zfs_access }, 3716 VOPNAME_LOOKUP, { .vop_lookup = zfs_lookup }, 3717 VOPNAME_RENAME, { .vop_rename = zfs_rename }, 3718 VOPNAME_FSYNC, { .vop_fsync = zfs_fsync }, 3719 VOPNAME_INACTIVE, { .vop_inactive = zfs_inactive }, 3720 VOPNAME_FID, { .vop_fid = zfs_fid }, 3721 VOPNAME_SEEK, { .vop_seek = zfs_seek }, 3722 VOPNAME_FRLOCK, { .vop_frlock = zfs_frlock }, 3723 VOPNAME_SPACE, { .vop_space = zfs_space }, 3724 VOPNAME_GETPAGE, { .vop_getpage = zfs_getpage }, 3725 VOPNAME_PUTPAGE, { .vop_putpage = zfs_putpage }, 3726 VOPNAME_MAP, { .vop_map = zfs_map }, 3727 VOPNAME_ADDMAP, { .vop_addmap = zfs_addmap }, 3728 VOPNAME_DELMAP, { .vop_delmap = zfs_delmap }, 3729 VOPNAME_PATHCONF, { .vop_pathconf = zfs_pathconf }, 3730 VOPNAME_GETSECATTR, { .vop_getsecattr = zfs_getsecattr }, 3731 VOPNAME_SETSECATTR, { .vop_setsecattr = zfs_setsecattr }, 3732 VOPNAME_VNEVENT, { .vop_vnevent = fs_vnevent_support }, 3733 NULL, NULL 3734 }; 3735 3736 /* 3737 * Symbolic link vnode operations template 3738 */ 3739 vnodeops_t *zfs_symvnodeops; 3740 const fs_operation_def_t zfs_symvnodeops_template[] = { 3741 VOPNAME_GETATTR, { .vop_getattr = zfs_getattr }, 3742 VOPNAME_SETATTR, { .vop_setattr = zfs_setattr }, 3743 VOPNAME_ACCESS, { .vop_access = zfs_access }, 3744 VOPNAME_RENAME, { .vop_rename = zfs_rename }, 3745 VOPNAME_READLINK, { .vop_readlink = zfs_readlink }, 3746 VOPNAME_INACTIVE, { .vop_inactive = zfs_inactive }, 3747 VOPNAME_FID, { .vop_fid = zfs_fid }, 3748 VOPNAME_PATHCONF, { .vop_pathconf = zfs_pathconf }, 3749 VOPNAME_VNEVENT, { .vop_vnevent = fs_vnevent_support }, 3750 NULL, NULL 3751 }; 3752 3753 /* 3754 * Extended attribute directory vnode operations template 3755 * This template is identical to the directory vnodes 3756 * operation template except for restricted operations: 3757 * VOP_MKDIR() 3758 * VOP_SYMLINK() 3759 * Note that there are other restrictions embedded in: 3760 * zfs_create() - restrict type to VREG 3761 * zfs_link() - no links into/out of attribute space 3762 * zfs_rename() - no moves into/out of attribute space 3763 */ 3764 vnodeops_t *zfs_xdvnodeops; 3765 const fs_operation_def_t zfs_xdvnodeops_template[] = { 3766 VOPNAME_OPEN, { .vop_open = zfs_open }, 3767 VOPNAME_CLOSE, { .vop_close = zfs_close }, 3768 VOPNAME_IOCTL, { .vop_ioctl = zfs_ioctl }, 3769 VOPNAME_GETATTR, { .vop_getattr = zfs_getattr }, 3770 VOPNAME_SETATTR, { .vop_setattr = zfs_setattr }, 3771 VOPNAME_ACCESS, { .vop_access = zfs_access }, 3772 VOPNAME_LOOKUP, { .vop_lookup = zfs_lookup }, 3773 VOPNAME_CREATE, { .vop_create = zfs_create }, 3774 VOPNAME_REMOVE, { .vop_remove = zfs_remove }, 3775 VOPNAME_LINK, { .vop_link = zfs_link }, 3776 VOPNAME_RENAME, { .vop_rename = zfs_rename }, 3777 VOPNAME_MKDIR, { .error = zfs_inval }, 3778 VOPNAME_RMDIR, { .vop_rmdir = zfs_rmdir }, 3779 VOPNAME_READDIR, { .vop_readdir = zfs_readdir }, 3780 VOPNAME_SYMLINK, { .error = zfs_inval }, 3781 VOPNAME_FSYNC, { .vop_fsync = zfs_fsync }, 3782 VOPNAME_INACTIVE, { .vop_inactive = zfs_inactive }, 3783 VOPNAME_FID, { .vop_fid = zfs_fid }, 3784 VOPNAME_SEEK, { .vop_seek = zfs_seek }, 3785 VOPNAME_PATHCONF, { .vop_pathconf = zfs_pathconf }, 3786 VOPNAME_GETSECATTR, { .vop_getsecattr = zfs_getsecattr }, 3787 VOPNAME_SETSECATTR, { .vop_setsecattr = zfs_setsecattr }, 3788 VOPNAME_VNEVENT, { .vop_vnevent = fs_vnevent_support }, 3789 NULL, NULL 3790 }; 3791 3792 /* 3793 * Error vnode operations template 3794 */ 3795 vnodeops_t *zfs_evnodeops; 3796 const fs_operation_def_t zfs_evnodeops_template[] = { 3797 VOPNAME_INACTIVE, { .vop_inactive = zfs_inactive }, 3798 VOPNAME_PATHCONF, { .vop_pathconf = zfs_pathconf }, 3799 NULL, NULL 3800 }; 3801