1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2013 Peter Grehan <grehan@freebsd.org> 5 * All rights reserved. 6 * Copyright 2020 Joyent, Inc. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * $FreeBSD$ 30 */ 31 32 /* 33 * Copyright 2020 Joyent, Inc. 34 */ 35 36 #include <sys/cdefs.h> 37 __FBSDID("$FreeBSD$"); 38 39 #include <sys/param.h> 40 #ifndef WITHOUT_CAPSICUM 41 #include <sys/capsicum.h> 42 #endif 43 #include <sys/queue.h> 44 #include <sys/errno.h> 45 #include <sys/stat.h> 46 #include <sys/ioctl.h> 47 #include <sys/disk.h> 48 #ifndef __FreeBSD__ 49 #include <sys/limits.h> 50 #include <sys/uio.h> 51 #include <sys/dkio.h> 52 #endif 53 54 #include <assert.h> 55 #ifndef WITHOUT_CAPSICUM 56 #include <capsicum_helpers.h> 57 #endif 58 #include <err.h> 59 #include <fcntl.h> 60 #include <stdio.h> 61 #include <stdlib.h> 62 #include <string.h> 63 #include <pthread.h> 64 #include <pthread_np.h> 65 #include <signal.h> 66 #include <sysexits.h> 67 #include <unistd.h> 68 69 #include <machine/atomic.h> 70 71 #include "bhyverun.h" 72 #include "config.h" 73 #include "debug.h" 74 #include "mevent.h" 75 #include "pci_emul.h" 76 #include "block_if.h" 77 78 #define BLOCKIF_SIG 0xb109b109 79 80 #ifdef __FreeBSD__ 81 #define BLOCKIF_NUMTHR 8 82 #else 83 /* Enlarge to keep pace with the virtio-block ring size */ 84 #define BLOCKIF_NUMTHR 16 85 #endif 86 #define BLOCKIF_MAXREQ (BLOCKIF_RING_MAX + BLOCKIF_NUMTHR) 87 88 enum blockop { 89 BOP_READ, 90 BOP_WRITE, 91 #ifndef __FreeBSD__ 92 BOP_WRITE_SYNC, 93 #endif 94 BOP_FLUSH, 95 BOP_DELETE 96 }; 97 98 enum blockstat { 99 BST_FREE, 100 BST_BLOCK, 101 BST_PEND, 102 BST_BUSY, 103 BST_DONE 104 }; 105 106 struct blockif_elem { 107 TAILQ_ENTRY(blockif_elem) be_link; 108 struct blockif_req *be_req; 109 enum blockop be_op; 110 enum blockstat be_status; 111 pthread_t be_tid; 112 off_t be_block; 113 }; 114 115 #ifndef __FreeBSD__ 116 enum blockif_wce { 117 WCE_NONE = 0, 118 WCE_IOCTL, 119 WCE_FCNTL 120 }; 121 #endif 122 123 struct blockif_ctxt { 124 unsigned int bc_magic; 125 int bc_fd; 126 int bc_ischr; 127 int bc_isgeom; 128 int bc_candelete; 129 #ifndef __FreeBSD__ 130 enum blockif_wce bc_wce; 131 #endif 132 int bc_rdonly; 133 off_t bc_size; 134 int bc_sectsz; 135 int bc_psectsz; 136 int bc_psectoff; 137 int bc_closing; 138 pthread_t bc_btid[BLOCKIF_NUMTHR]; 139 pthread_mutex_t bc_mtx; 140 pthread_cond_t bc_cond; 141 blockif_resize_cb *bc_resize_cb; 142 void *bc_resize_cb_arg; 143 struct mevent *bc_resize_event; 144 145 /* Request elements and free/pending/busy queues */ 146 TAILQ_HEAD(, blockif_elem) bc_freeq; 147 TAILQ_HEAD(, blockif_elem) bc_pendq; 148 TAILQ_HEAD(, blockif_elem) bc_busyq; 149 struct blockif_elem bc_reqs[BLOCKIF_MAXREQ]; 150 }; 151 152 static pthread_once_t blockif_once = PTHREAD_ONCE_INIT; 153 154 struct blockif_sig_elem { 155 pthread_mutex_t bse_mtx; 156 pthread_cond_t bse_cond; 157 int bse_pending; 158 struct blockif_sig_elem *bse_next; 159 }; 160 161 static struct blockif_sig_elem *blockif_bse_head; 162 163 static int 164 blockif_enqueue(struct blockif_ctxt *bc, struct blockif_req *breq, 165 enum blockop op) 166 { 167 struct blockif_elem *be, *tbe; 168 off_t off; 169 int i; 170 171 be = TAILQ_FIRST(&bc->bc_freeq); 172 assert(be != NULL); 173 assert(be->be_status == BST_FREE); 174 TAILQ_REMOVE(&bc->bc_freeq, be, be_link); 175 be->be_req = breq; 176 be->be_op = op; 177 switch (op) { 178 case BOP_READ: 179 case BOP_WRITE: 180 #ifndef __FreeBSD__ 181 case BOP_WRITE_SYNC: 182 #endif 183 case BOP_DELETE: 184 off = breq->br_offset; 185 for (i = 0; i < breq->br_iovcnt; i++) 186 off += breq->br_iov[i].iov_len; 187 break; 188 default: 189 off = OFF_MAX; 190 } 191 be->be_block = off; 192 TAILQ_FOREACH(tbe, &bc->bc_pendq, be_link) { 193 if (tbe->be_block == breq->br_offset) 194 break; 195 } 196 if (tbe == NULL) { 197 TAILQ_FOREACH(tbe, &bc->bc_busyq, be_link) { 198 if (tbe->be_block == breq->br_offset) 199 break; 200 } 201 } 202 if (tbe == NULL) 203 be->be_status = BST_PEND; 204 else 205 be->be_status = BST_BLOCK; 206 TAILQ_INSERT_TAIL(&bc->bc_pendq, be, be_link); 207 return (be->be_status == BST_PEND); 208 } 209 210 static int 211 blockif_dequeue(struct blockif_ctxt *bc, pthread_t t, struct blockif_elem **bep) 212 { 213 struct blockif_elem *be; 214 215 TAILQ_FOREACH(be, &bc->bc_pendq, be_link) { 216 if (be->be_status == BST_PEND) 217 break; 218 assert(be->be_status == BST_BLOCK); 219 } 220 if (be == NULL) 221 return (0); 222 TAILQ_REMOVE(&bc->bc_pendq, be, be_link); 223 be->be_status = BST_BUSY; 224 be->be_tid = t; 225 TAILQ_INSERT_TAIL(&bc->bc_busyq, be, be_link); 226 *bep = be; 227 return (1); 228 } 229 230 static void 231 blockif_complete(struct blockif_ctxt *bc, struct blockif_elem *be) 232 { 233 struct blockif_elem *tbe; 234 235 if (be->be_status == BST_DONE || be->be_status == BST_BUSY) 236 TAILQ_REMOVE(&bc->bc_busyq, be, be_link); 237 else 238 TAILQ_REMOVE(&bc->bc_pendq, be, be_link); 239 TAILQ_FOREACH(tbe, &bc->bc_pendq, be_link) { 240 if (tbe->be_req->br_offset == be->be_block) 241 tbe->be_status = BST_PEND; 242 } 243 be->be_tid = 0; 244 be->be_status = BST_FREE; 245 be->be_req = NULL; 246 TAILQ_INSERT_TAIL(&bc->bc_freeq, be, be_link); 247 } 248 249 static int 250 blockif_flush_bc(struct blockif_ctxt *bc) 251 { 252 #ifdef __FreeBSD__ 253 if (bc->bc_ischr) { 254 if (ioctl(bc->bc_fd, DIOCGFLUSH)) 255 return (errno); 256 } else if (fsync(bc->bc_fd)) 257 return (errno); 258 #else 259 /* 260 * This fsync() should be adequate to flush the cache of a file 261 * or device. In VFS, the VOP_SYNC operation is converted to 262 * the appropriate ioctl in both sdev (for real devices) and 263 * zfs (for zvols). 264 */ 265 if (fsync(bc->bc_fd)) 266 return (errno); 267 #endif 268 269 return (0); 270 } 271 272 static void 273 blockif_proc(struct blockif_ctxt *bc, struct blockif_elem *be, uint8_t *buf) 274 { 275 #ifdef __FreeBSD__ 276 struct spacectl_range range; 277 #endif 278 struct blockif_req *br; 279 #ifdef __FreeBSD__ 280 off_t arg[2]; 281 #endif 282 ssize_t n; 283 size_t clen, len, off, boff, voff; 284 int i, err; 285 286 br = be->be_req; 287 assert(br->br_resid >= 0); 288 289 if (br->br_iovcnt <= 1) 290 buf = NULL; 291 err = 0; 292 switch (be->be_op) { 293 case BOP_READ: 294 if (buf == NULL) { 295 if ((n = preadv(bc->bc_fd, br->br_iov, br->br_iovcnt, 296 br->br_offset)) < 0) 297 err = errno; 298 else 299 br->br_resid -= n; 300 break; 301 } 302 i = 0; 303 off = voff = 0; 304 while (br->br_resid > 0) { 305 len = MIN(br->br_resid, MAXPHYS); 306 n = pread(bc->bc_fd, buf, len, br->br_offset + off); 307 if (n < 0) { 308 err = errno; 309 break; 310 } 311 len = (size_t)n; 312 boff = 0; 313 do { 314 clen = MIN(len - boff, br->br_iov[i].iov_len - 315 voff); 316 memcpy((uint8_t *)br->br_iov[i].iov_base + voff, 317 buf + boff, clen); 318 if (clen < br->br_iov[i].iov_len - voff) 319 voff += clen; 320 else { 321 i++; 322 voff = 0; 323 } 324 boff += clen; 325 } while (boff < len); 326 off += len; 327 br->br_resid -= len; 328 } 329 break; 330 case BOP_WRITE: 331 if (bc->bc_rdonly) { 332 err = EROFS; 333 break; 334 } 335 if (buf == NULL) { 336 if ((n = pwritev(bc->bc_fd, br->br_iov, br->br_iovcnt, 337 br->br_offset)) < 0) 338 err = errno; 339 else 340 br->br_resid -= n; 341 break; 342 } 343 i = 0; 344 off = voff = 0; 345 while (br->br_resid > 0) { 346 len = MIN(br->br_resid, MAXPHYS); 347 boff = 0; 348 do { 349 clen = MIN(len - boff, br->br_iov[i].iov_len - 350 voff); 351 memcpy(buf + boff, 352 (uint8_t *)br->br_iov[i].iov_base + voff, 353 clen); 354 if (clen < br->br_iov[i].iov_len - voff) 355 voff += clen; 356 else { 357 i++; 358 voff = 0; 359 } 360 boff += clen; 361 } while (boff < len); 362 363 n = pwrite(bc->bc_fd, buf, len, br->br_offset + off); 364 if (n < 0) { 365 err = errno; 366 break; 367 } 368 off += n; 369 br->br_resid -= n; 370 } 371 break; 372 case BOP_FLUSH: 373 err = blockif_flush_bc(bc); 374 break; 375 case BOP_DELETE: 376 if (!bc->bc_candelete) 377 err = EOPNOTSUPP; 378 else if (bc->bc_rdonly) 379 err = EROFS; 380 #ifdef __FreeBSD__ 381 else if (bc->bc_ischr) { 382 arg[0] = br->br_offset; 383 arg[1] = br->br_resid; 384 if (ioctl(bc->bc_fd, DIOCGDELETE, arg)) 385 err = errno; 386 else 387 br->br_resid = 0; 388 } else { 389 range.r_offset = br->br_offset; 390 range.r_len = br->br_resid; 391 392 while (range.r_len > 0) { 393 if (fspacectl(bc->bc_fd, SPACECTL_DEALLOC, 394 &range, 0, &range) != 0) { 395 err = errno; 396 break; 397 } 398 } 399 if (err == 0) 400 br->br_resid = 0; 401 } 402 #else 403 else if (bc->bc_ischr) { 404 dkioc_free_list_t dfl = { 405 .dfl_num_exts = 1, 406 .dfl_offset = 0, 407 .dfl_flags = 0, 408 .dfl_exts = { 409 { 410 .dfle_start = br->br_offset, 411 .dfle_length = br->br_resid 412 } 413 } 414 }; 415 416 if (ioctl(bc->bc_fd, DKIOCFREE, &dfl)) 417 err = errno; 418 else 419 br->br_resid = 0; 420 } else { 421 struct flock fl = { 422 .l_whence = 0, 423 .l_type = F_WRLCK, 424 .l_start = br->br_offset, 425 .l_len = br->br_resid 426 }; 427 428 if (fcntl(bc->bc_fd, F_FREESP, &fl)) 429 err = errno; 430 else 431 br->br_resid = 0; 432 } 433 #endif 434 break; 435 default: 436 err = EINVAL; 437 break; 438 } 439 440 be->be_status = BST_DONE; 441 442 (*br->br_callback)(br, err); 443 } 444 445 static inline bool 446 blockif_empty(const struct blockif_ctxt *bc) 447 { 448 return (TAILQ_EMPTY(&bc->bc_pendq) && TAILQ_EMPTY(&bc->bc_busyq)); 449 } 450 451 static void * 452 blockif_thr(void *arg) 453 { 454 struct blockif_ctxt *bc; 455 struct blockif_elem *be; 456 pthread_t t; 457 uint8_t *buf; 458 459 bc = arg; 460 if (bc->bc_isgeom) 461 buf = malloc(MAXPHYS); 462 else 463 buf = NULL; 464 t = pthread_self(); 465 466 pthread_mutex_lock(&bc->bc_mtx); 467 for (;;) { 468 while (blockif_dequeue(bc, t, &be)) { 469 pthread_mutex_unlock(&bc->bc_mtx); 470 blockif_proc(bc, be, buf); 471 pthread_mutex_lock(&bc->bc_mtx); 472 blockif_complete(bc, be); 473 } 474 /* Check ctxt status here to see if exit requested */ 475 if (bc->bc_closing) 476 break; 477 478 pthread_cond_wait(&bc->bc_cond, &bc->bc_mtx); 479 } 480 pthread_mutex_unlock(&bc->bc_mtx); 481 482 if (buf) 483 free(buf); 484 pthread_exit(NULL); 485 return (NULL); 486 } 487 488 #ifdef __FreeBSD__ 489 static void 490 blockif_sigcont_handler(int signal __unused, enum ev_type type __unused, 491 void *arg __unused) 492 #else 493 static void 494 blockif_sigcont_handler(int signal __unused) 495 #endif 496 { 497 struct blockif_sig_elem *bse; 498 499 for (;;) { 500 /* 501 * Process the entire list even if not intended for 502 * this thread. 503 */ 504 do { 505 bse = blockif_bse_head; 506 if (bse == NULL) 507 return; 508 } while (!atomic_cmpset_ptr((uintptr_t *)&blockif_bse_head, 509 (uintptr_t)bse, 510 (uintptr_t)bse->bse_next)); 511 512 pthread_mutex_lock(&bse->bse_mtx); 513 bse->bse_pending = 0; 514 pthread_cond_signal(&bse->bse_cond); 515 pthread_mutex_unlock(&bse->bse_mtx); 516 } 517 } 518 519 static void 520 blockif_init(void) 521 { 522 #ifdef __FreeBSD__ 523 mevent_add(SIGCONT, EVF_SIGNAL, blockif_sigcont_handler, NULL); 524 (void) signal(SIGCONT, SIG_IGN); 525 #else 526 (void) sigset(SIGCONT, blockif_sigcont_handler); 527 #endif 528 } 529 530 int 531 blockif_legacy_config(nvlist_t *nvl, const char *opts) 532 { 533 char *cp, *path; 534 535 if (opts == NULL) 536 return (0); 537 538 cp = strchr(opts, ','); 539 if (cp == NULL) { 540 set_config_value_node(nvl, "path", opts); 541 return (0); 542 } 543 path = strndup(opts, cp - opts); 544 set_config_value_node(nvl, "path", path); 545 free(path); 546 return (pci_parse_legacy_config(nvl, cp + 1)); 547 } 548 549 struct blockif_ctxt * 550 blockif_open(nvlist_t *nvl, const char *ident) 551 { 552 char tname[MAXCOMLEN + 1]; 553 #ifdef __FreeBSD__ 554 char name[MAXPATHLEN]; 555 #endif 556 const char *path, *pssval, *ssval; 557 char *cp; 558 struct blockif_ctxt *bc; 559 struct stat sbuf; 560 #ifdef __FreeBSD__ 561 struct diocgattr_arg arg; 562 #else 563 enum blockif_wce wce = WCE_NONE; 564 #endif 565 off_t size, psectsz, psectoff; 566 int extra, fd, i, sectsz; 567 int ro, candelete, geom, ssopt, pssopt; 568 int nodelete; 569 570 #ifndef WITHOUT_CAPSICUM 571 cap_rights_t rights; 572 cap_ioctl_t cmds[] = { DIOCGFLUSH, DIOCGDELETE, DIOCGMEDIASIZE }; 573 #endif 574 575 pthread_once(&blockif_once, blockif_init); 576 577 fd = -1; 578 extra = 0; 579 ssopt = 0; 580 #ifndef __FreeBSD__ 581 pssopt = 0; 582 #endif 583 ro = 0; 584 nodelete = 0; 585 586 if (get_config_bool_node_default(nvl, "nocache", false)) 587 extra |= O_DIRECT; 588 if (get_config_bool_node_default(nvl, "nodelete", false)) 589 nodelete = 1; 590 if (get_config_bool_node_default(nvl, "sync", false) || 591 get_config_bool_node_default(nvl, "direct", false)) 592 extra |= O_SYNC; 593 if (get_config_bool_node_default(nvl, "ro", false)) 594 ro = 1; 595 ssval = get_config_value_node(nvl, "sectorsize"); 596 if (ssval != NULL) { 597 ssopt = strtol(ssval, &cp, 10); 598 if (cp == ssval) { 599 EPRINTLN("Invalid sector size \"%s\"", ssval); 600 goto err; 601 } 602 if (*cp == '\0') { 603 pssopt = ssopt; 604 } else if (*cp == '/') { 605 pssval = cp + 1; 606 pssopt = strtol(pssval, &cp, 10); 607 if (cp == pssval || *cp != '\0') { 608 EPRINTLN("Invalid sector size \"%s\"", ssval); 609 goto err; 610 } 611 } else { 612 EPRINTLN("Invalid sector size \"%s\"", ssval); 613 goto err; 614 } 615 } 616 617 path = get_config_value_node(nvl, "path"); 618 if (path == NULL) { 619 EPRINTLN("Missing \"path\" for block device."); 620 goto err; 621 } 622 623 fd = open(path, (ro ? O_RDONLY : O_RDWR) | extra); 624 if (fd < 0 && !ro) { 625 /* Attempt a r/w fail with a r/o open */ 626 fd = open(path, O_RDONLY | extra); 627 ro = 1; 628 } 629 630 if (fd < 0) { 631 warn("Could not open backing file: %s", path); 632 goto err; 633 } 634 635 if (fstat(fd, &sbuf) < 0) { 636 warn("Could not stat backing file %s", path); 637 goto err; 638 } 639 640 #ifndef WITHOUT_CAPSICUM 641 cap_rights_init(&rights, CAP_FSYNC, CAP_IOCTL, CAP_READ, CAP_SEEK, 642 CAP_WRITE, CAP_FSTAT, CAP_EVENT, CAP_FPATHCONF); 643 if (ro) 644 cap_rights_clear(&rights, CAP_FSYNC, CAP_WRITE); 645 646 if (caph_rights_limit(fd, &rights) == -1) 647 errx(EX_OSERR, "Unable to apply rights for sandbox"); 648 #endif 649 650 /* 651 * Deal with raw devices 652 */ 653 size = sbuf.st_size; 654 sectsz = DEV_BSIZE; 655 psectsz = psectoff = 0; 656 candelete = geom = 0; 657 #ifdef __FreeBSD__ 658 if (S_ISCHR(sbuf.st_mode)) { 659 if (ioctl(fd, DIOCGMEDIASIZE, &size) < 0 || 660 ioctl(fd, DIOCGSECTORSIZE, §sz)) { 661 perror("Could not fetch dev blk/sector size"); 662 goto err; 663 } 664 assert(size != 0); 665 assert(sectsz != 0); 666 if (ioctl(fd, DIOCGSTRIPESIZE, &psectsz) == 0 && psectsz > 0) 667 ioctl(fd, DIOCGSTRIPEOFFSET, &psectoff); 668 strlcpy(arg.name, "GEOM::candelete", sizeof(arg.name)); 669 arg.len = sizeof(arg.value.i); 670 if (nodelete == 0 && ioctl(fd, DIOCGATTR, &arg) == 0) 671 candelete = arg.value.i; 672 if (ioctl(fd, DIOCGPROVIDERNAME, name) == 0) 673 geom = 1; 674 } else { 675 psectsz = sbuf.st_blksize; 676 /* Avoid fallback implementation */ 677 candelete = fpathconf(fd, _PC_DEALLOC_PRESENT) == 1; 678 } 679 #else 680 psectsz = sbuf.st_blksize; 681 if (S_ISCHR(sbuf.st_mode)) { 682 struct dk_minfo_ext dkmext; 683 int wce_val; 684 685 /* Look for a more accurate physical block/media size */ 686 if (ioctl(fd, DKIOCGMEDIAINFOEXT, &dkmext) == 0) { 687 psectsz = dkmext.dki_pbsize; 688 size = dkmext.dki_lbsize * dkmext.dki_capacity; 689 } 690 /* See if a configurable write cache is present and working */ 691 if (ioctl(fd, DKIOCGETWCE, &wce_val) == 0) { 692 /* 693 * If WCE is already active, disable it until the 694 * specific device driver calls for its return. If it 695 * is not active, toggle it on and off to verify that 696 * such actions are possible. 697 */ 698 if (wce_val != 0) { 699 wce_val = 0; 700 /* 701 * Inability to disable the cache is a threat 702 * to data durability. 703 */ 704 assert(ioctl(fd, DKIOCSETWCE, &wce_val) == 0); 705 wce = WCE_IOCTL; 706 } else { 707 int r1, r2; 708 709 wce_val = 1; 710 r1 = ioctl(fd, DKIOCSETWCE, &wce_val); 711 wce_val = 0; 712 r2 = ioctl(fd, DKIOCSETWCE, &wce_val); 713 714 if (r1 == 0 && r2 == 0) { 715 wce = WCE_IOCTL; 716 } else { 717 /* 718 * If the cache cache toggle was not 719 * successful, ensure that the cache 720 * was not left enabled. 721 */ 722 assert(r1 != 0); 723 } 724 } 725 } 726 727 if (nodelete == 0 && ioctl(fd, DKIOC_CANFREE, &candelete)) 728 candelete = 0; 729 730 } else { 731 int flags; 732 733 if ((flags = fcntl(fd, F_GETFL)) >= 0) { 734 flags |= O_DSYNC; 735 if (fcntl(fd, F_SETFL, flags) != -1) { 736 wce = WCE_FCNTL; 737 } 738 } 739 740 /* 741 * We don't have a way to discover if a file supports the 742 * FREESP fcntl cmd (other than trying it). However, 743 * zfs, ufs, tmpfs, and udfs all support the FREESP fcntl cmd. 744 * Nfsv4 and nfsv4 also forward the FREESP request 745 * to the server, so we always enable it for file based 746 * volumes. Anyone trying to run volumes on an unsupported 747 * configuration is on their own, and should be prepared 748 * for the requests to fail. 749 */ 750 if (nodelete == 0) 751 candelete = 1; 752 } 753 #endif 754 755 #ifndef WITHOUT_CAPSICUM 756 if (caph_ioctls_limit(fd, cmds, nitems(cmds)) == -1) 757 errx(EX_OSERR, "Unable to apply rights for sandbox"); 758 #endif 759 760 if (ssopt != 0) { 761 if (!powerof2(ssopt) || !powerof2(pssopt) || ssopt < 512 || 762 ssopt > pssopt) { 763 EPRINTLN("Invalid sector size %d/%d", 764 ssopt, pssopt); 765 goto err; 766 } 767 768 /* 769 * Some backend drivers (e.g. cd0, ada0) require that the I/O 770 * size be a multiple of the device's sector size. 771 * 772 * Validate that the emulated sector size complies with this 773 * requirement. 774 */ 775 if (S_ISCHR(sbuf.st_mode)) { 776 if (ssopt < sectsz || (ssopt % sectsz) != 0) { 777 EPRINTLN("Sector size %d incompatible " 778 "with underlying device sector size %d", 779 ssopt, sectsz); 780 goto err; 781 } 782 } 783 784 sectsz = ssopt; 785 psectsz = pssopt; 786 psectoff = 0; 787 } 788 789 bc = calloc(1, sizeof(struct blockif_ctxt)); 790 if (bc == NULL) { 791 perror("calloc"); 792 goto err; 793 } 794 795 bc->bc_magic = BLOCKIF_SIG; 796 bc->bc_fd = fd; 797 bc->bc_ischr = S_ISCHR(sbuf.st_mode); 798 bc->bc_isgeom = geom; 799 bc->bc_candelete = candelete; 800 #ifndef __FreeBSD__ 801 bc->bc_wce = wce; 802 #endif 803 bc->bc_rdonly = ro; 804 bc->bc_size = size; 805 bc->bc_sectsz = sectsz; 806 bc->bc_psectsz = psectsz; 807 bc->bc_psectoff = psectoff; 808 pthread_mutex_init(&bc->bc_mtx, NULL); 809 pthread_cond_init(&bc->bc_cond, NULL); 810 TAILQ_INIT(&bc->bc_freeq); 811 TAILQ_INIT(&bc->bc_pendq); 812 TAILQ_INIT(&bc->bc_busyq); 813 for (i = 0; i < BLOCKIF_MAXREQ; i++) { 814 bc->bc_reqs[i].be_status = BST_FREE; 815 TAILQ_INSERT_HEAD(&bc->bc_freeq, &bc->bc_reqs[i], be_link); 816 } 817 818 for (i = 0; i < BLOCKIF_NUMTHR; i++) { 819 pthread_create(&bc->bc_btid[i], NULL, blockif_thr, bc); 820 snprintf(tname, sizeof(tname), "blk-%s-%d", ident, i); 821 pthread_set_name_np(bc->bc_btid[i], tname); 822 } 823 824 return (bc); 825 err: 826 if (fd >= 0) 827 close(fd); 828 return (NULL); 829 } 830 831 static void 832 blockif_resized(int fd, enum ev_type type __unused, void *arg) 833 { 834 struct blockif_ctxt *bc; 835 struct stat sb; 836 off_t mediasize; 837 838 if (fstat(fd, &sb) != 0) 839 return; 840 841 #ifdef __FreeBSD__ 842 if (S_ISCHR(sb.st_mode)) { 843 if (ioctl(fd, DIOCGMEDIASIZE, &mediasize) < 0) { 844 EPRINTLN("blockif_resized: get mediasize failed: %s", 845 strerror(errno)); 846 return; 847 } 848 } else 849 mediasize = sb.st_size; 850 #else 851 mediasize = sb.st_size; 852 if (S_ISCHR(sb.st_mode)) { 853 struct dk_minfo dkm; 854 855 if (ioctl(fd, DKIOCGMEDIAINFO, &dkm) == 0) 856 mediasize = dkm.dki_lbsize * dkm.dki_capacity; 857 } 858 #endif 859 860 bc = arg; 861 pthread_mutex_lock(&bc->bc_mtx); 862 if (mediasize != bc->bc_size) { 863 bc->bc_size = mediasize; 864 bc->bc_resize_cb(bc, bc->bc_resize_cb_arg, bc->bc_size); 865 } 866 pthread_mutex_unlock(&bc->bc_mtx); 867 } 868 869 int 870 blockif_register_resize_callback(struct blockif_ctxt *bc, blockif_resize_cb *cb, 871 void *cb_arg) 872 { 873 struct stat sb; 874 int err; 875 876 if (cb == NULL) 877 return (EINVAL); 878 879 err = 0; 880 881 pthread_mutex_lock(&bc->bc_mtx); 882 if (bc->bc_resize_cb != NULL) { 883 err = EBUSY; 884 goto out; 885 } 886 887 assert(bc->bc_closing == 0); 888 889 if (fstat(bc->bc_fd, &sb) != 0) { 890 err = errno; 891 goto out; 892 } 893 894 bc->bc_resize_event = mevent_add_flags(bc->bc_fd, EVF_VNODE, 895 EVFF_ATTRIB, blockif_resized, bc); 896 if (bc->bc_resize_event == NULL) { 897 err = ENXIO; 898 goto out; 899 } 900 901 bc->bc_resize_cb = cb; 902 bc->bc_resize_cb_arg = cb_arg; 903 out: 904 pthread_mutex_unlock(&bc->bc_mtx); 905 906 return (err); 907 } 908 909 static int 910 blockif_request(struct blockif_ctxt *bc, struct blockif_req *breq, 911 enum blockop op) 912 { 913 int err; 914 915 err = 0; 916 917 pthread_mutex_lock(&bc->bc_mtx); 918 if (!TAILQ_EMPTY(&bc->bc_freeq)) { 919 /* 920 * Enqueue and inform the block i/o thread 921 * that there is work available 922 */ 923 if (blockif_enqueue(bc, breq, op)) 924 pthread_cond_signal(&bc->bc_cond); 925 } else { 926 /* 927 * Callers are not allowed to enqueue more than 928 * the specified blockif queue limit. Return an 929 * error to indicate that the queue length has been 930 * exceeded. 931 */ 932 err = E2BIG; 933 } 934 pthread_mutex_unlock(&bc->bc_mtx); 935 936 return (err); 937 } 938 939 int 940 blockif_read(struct blockif_ctxt *bc, struct blockif_req *breq) 941 { 942 assert(bc->bc_magic == BLOCKIF_SIG); 943 return (blockif_request(bc, breq, BOP_READ)); 944 } 945 946 int 947 blockif_write(struct blockif_ctxt *bc, struct blockif_req *breq) 948 { 949 assert(bc->bc_magic == BLOCKIF_SIG); 950 return (blockif_request(bc, breq, BOP_WRITE)); 951 } 952 953 int 954 blockif_flush(struct blockif_ctxt *bc, struct blockif_req *breq) 955 { 956 assert(bc->bc_magic == BLOCKIF_SIG); 957 return (blockif_request(bc, breq, BOP_FLUSH)); 958 } 959 960 int 961 blockif_delete(struct blockif_ctxt *bc, struct blockif_req *breq) 962 { 963 assert(bc->bc_magic == BLOCKIF_SIG); 964 return (blockif_request(bc, breq, BOP_DELETE)); 965 } 966 967 int 968 blockif_cancel(struct blockif_ctxt *bc, struct blockif_req *breq) 969 { 970 struct blockif_elem *be; 971 972 assert(bc->bc_magic == BLOCKIF_SIG); 973 974 pthread_mutex_lock(&bc->bc_mtx); 975 /* 976 * Check pending requests. 977 */ 978 TAILQ_FOREACH(be, &bc->bc_pendq, be_link) { 979 if (be->be_req == breq) 980 break; 981 } 982 if (be != NULL) { 983 /* 984 * Found it. 985 */ 986 blockif_complete(bc, be); 987 pthread_mutex_unlock(&bc->bc_mtx); 988 989 return (0); 990 } 991 992 /* 993 * Check in-flight requests. 994 */ 995 TAILQ_FOREACH(be, &bc->bc_busyq, be_link) { 996 if (be->be_req == breq) 997 break; 998 } 999 if (be == NULL) { 1000 /* 1001 * Didn't find it. 1002 */ 1003 pthread_mutex_unlock(&bc->bc_mtx); 1004 return (EINVAL); 1005 } 1006 1007 /* 1008 * Interrupt the processing thread to force it return 1009 * prematurely via it's normal callback path. 1010 */ 1011 while (be->be_status == BST_BUSY) { 1012 struct blockif_sig_elem bse, *old_head; 1013 1014 pthread_mutex_init(&bse.bse_mtx, NULL); 1015 pthread_cond_init(&bse.bse_cond, NULL); 1016 1017 bse.bse_pending = 1; 1018 1019 do { 1020 old_head = blockif_bse_head; 1021 bse.bse_next = old_head; 1022 } while (!atomic_cmpset_ptr((uintptr_t *)&blockif_bse_head, 1023 (uintptr_t)old_head, 1024 (uintptr_t)&bse)); 1025 1026 pthread_kill(be->be_tid, SIGCONT); 1027 1028 pthread_mutex_lock(&bse.bse_mtx); 1029 while (bse.bse_pending) 1030 pthread_cond_wait(&bse.bse_cond, &bse.bse_mtx); 1031 pthread_mutex_unlock(&bse.bse_mtx); 1032 } 1033 1034 pthread_mutex_unlock(&bc->bc_mtx); 1035 1036 /* 1037 * The processing thread has been interrupted. Since it's not 1038 * clear if the callback has been invoked yet, return EBUSY. 1039 */ 1040 return (EBUSY); 1041 } 1042 1043 int 1044 blockif_close(struct blockif_ctxt *bc) 1045 { 1046 void *jval; 1047 int i; 1048 1049 assert(bc->bc_magic == BLOCKIF_SIG); 1050 1051 /* 1052 * Stop the block i/o thread 1053 */ 1054 pthread_mutex_lock(&bc->bc_mtx); 1055 bc->bc_closing = 1; 1056 if (bc->bc_resize_event != NULL) 1057 mevent_disable(bc->bc_resize_event); 1058 pthread_mutex_unlock(&bc->bc_mtx); 1059 pthread_cond_broadcast(&bc->bc_cond); 1060 for (i = 0; i < BLOCKIF_NUMTHR; i++) 1061 pthread_join(bc->bc_btid[i], &jval); 1062 1063 /* XXX Cancel queued i/o's ??? */ 1064 1065 /* 1066 * Release resources 1067 */ 1068 bc->bc_magic = 0; 1069 close(bc->bc_fd); 1070 free(bc); 1071 1072 return (0); 1073 } 1074 1075 /* 1076 * Return virtual C/H/S values for a given block. Use the algorithm 1077 * outlined in the VHD specification to calculate values. 1078 */ 1079 void 1080 blockif_chs(struct blockif_ctxt *bc, uint16_t *c, uint8_t *h, uint8_t *s) 1081 { 1082 off_t sectors; /* total sectors of the block dev */ 1083 off_t hcyl; /* cylinders times heads */ 1084 uint16_t secpt; /* sectors per track */ 1085 uint8_t heads; 1086 1087 assert(bc->bc_magic == BLOCKIF_SIG); 1088 1089 sectors = bc->bc_size / bc->bc_sectsz; 1090 1091 /* Clamp the size to the largest possible with CHS */ 1092 if (sectors > 65535L * 16 * 255) 1093 sectors = 65535L * 16 * 255; 1094 1095 if (sectors >= 65536L * 16 * 63) { 1096 secpt = 255; 1097 heads = 16; 1098 hcyl = sectors / secpt; 1099 } else { 1100 secpt = 17; 1101 hcyl = sectors / secpt; 1102 heads = (hcyl + 1023) / 1024; 1103 1104 if (heads < 4) 1105 heads = 4; 1106 1107 if (hcyl >= (heads * 1024) || heads > 16) { 1108 secpt = 31; 1109 heads = 16; 1110 hcyl = sectors / secpt; 1111 } 1112 if (hcyl >= (heads * 1024)) { 1113 secpt = 63; 1114 heads = 16; 1115 hcyl = sectors / secpt; 1116 } 1117 } 1118 1119 *c = hcyl / heads; 1120 *h = heads; 1121 *s = secpt; 1122 } 1123 1124 /* 1125 * Accessors 1126 */ 1127 off_t 1128 blockif_size(struct blockif_ctxt *bc) 1129 { 1130 assert(bc->bc_magic == BLOCKIF_SIG); 1131 return (bc->bc_size); 1132 } 1133 1134 int 1135 blockif_sectsz(struct blockif_ctxt *bc) 1136 { 1137 assert(bc->bc_magic == BLOCKIF_SIG); 1138 return (bc->bc_sectsz); 1139 } 1140 1141 void 1142 blockif_psectsz(struct blockif_ctxt *bc, int *size, int *off) 1143 { 1144 assert(bc->bc_magic == BLOCKIF_SIG); 1145 *size = bc->bc_psectsz; 1146 *off = bc->bc_psectoff; 1147 } 1148 1149 int 1150 blockif_queuesz(struct blockif_ctxt *bc) 1151 { 1152 assert(bc->bc_magic == BLOCKIF_SIG); 1153 return (BLOCKIF_MAXREQ - 1); 1154 } 1155 1156 int 1157 blockif_is_ro(struct blockif_ctxt *bc) 1158 { 1159 assert(bc->bc_magic == BLOCKIF_SIG); 1160 return (bc->bc_rdonly); 1161 } 1162 1163 int 1164 blockif_candelete(struct blockif_ctxt *bc) 1165 { 1166 assert(bc->bc_magic == BLOCKIF_SIG); 1167 return (bc->bc_candelete); 1168 } 1169 1170 #ifndef __FreeBSD__ 1171 int 1172 blockif_set_wce(struct blockif_ctxt *bc, int wc_enable) 1173 { 1174 int res = 0, flags; 1175 int clean_val = (wc_enable != 0) ? 1 : 0; 1176 1177 (void) pthread_mutex_lock(&bc->bc_mtx); 1178 switch (bc->bc_wce) { 1179 case WCE_IOCTL: 1180 res = ioctl(bc->bc_fd, DKIOCSETWCE, &clean_val); 1181 break; 1182 case WCE_FCNTL: 1183 if ((flags = fcntl(bc->bc_fd, F_GETFL)) >= 0) { 1184 if (wc_enable == 0) { 1185 flags |= O_DSYNC; 1186 } else { 1187 flags &= ~O_DSYNC; 1188 } 1189 if (fcntl(bc->bc_fd, F_SETFL, flags) == -1) { 1190 res = -1; 1191 } 1192 } else { 1193 res = -1; 1194 } 1195 break; 1196 default: 1197 break; 1198 } 1199 1200 /* 1201 * After a successful disable of the write cache, ensure that any 1202 * lingering data in the cache is synced out. 1203 */ 1204 if (res == 0 && wc_enable == 0) { 1205 res = fsync(bc->bc_fd); 1206 } 1207 (void) pthread_mutex_unlock(&bc->bc_mtx); 1208 1209 return (res); 1210 } 1211 #endif /* __FreeBSD__ */ 1212