1 /* 2 * GlusterFS backend for QEMU 3 * 4 * Copyright (C) 2012 Bharata B Rao <bharata@linux.vnet.ibm.com> 5 * 6 * This work is licensed under the terms of the GNU GPL, version 2 or later. 7 * See the COPYING file in the top-level directory. 8 * 9 */ 10 11 #include "qemu/osdep.h" 12 #include "qemu/units.h" 13 #include <glusterfs/api/glfs.h> 14 #include "block/block_int.h" 15 #include "block/qdict.h" 16 #include "qapi/error.h" 17 #include "qapi/qmp/qdict.h" 18 #include "qapi/qmp/qerror.h" 19 #include "qemu/uri.h" 20 #include "qemu/error-report.h" 21 #include "qemu/module.h" 22 #include "qemu/option.h" 23 #include "qemu/cutils.h" 24 25 #ifdef CONFIG_GLUSTERFS_FTRUNCATE_HAS_STAT 26 # define glfs_ftruncate(fd, offset) glfs_ftruncate(fd, offset, NULL, NULL) 27 #endif 28 29 #define GLUSTER_OPT_FILENAME "filename" 30 #define GLUSTER_OPT_VOLUME "volume" 31 #define GLUSTER_OPT_PATH "path" 32 #define GLUSTER_OPT_TYPE "type" 33 #define GLUSTER_OPT_SERVER_PATTERN "server." 34 #define GLUSTER_OPT_HOST "host" 35 #define GLUSTER_OPT_PORT "port" 36 #define GLUSTER_OPT_TO "to" 37 #define GLUSTER_OPT_IPV4 "ipv4" 38 #define GLUSTER_OPT_IPV6 "ipv6" 39 #define GLUSTER_OPT_SOCKET "socket" 40 #define GLUSTER_OPT_DEBUG "debug" 41 #define GLUSTER_DEFAULT_PORT 24007 42 #define GLUSTER_DEBUG_DEFAULT 4 43 #define GLUSTER_DEBUG_MAX 9 44 #define GLUSTER_OPT_LOGFILE "logfile" 45 #define GLUSTER_LOGFILE_DEFAULT "-" /* handled in libgfapi as /dev/stderr */ 46 /* 47 * Several versions of GlusterFS (3.12? -> 6.0.1) fail when the transfer size 48 * is greater or equal to 1024 MiB, so we are limiting the transfer size to 512 49 * MiB to avoid this rare issue. 50 */ 51 #define GLUSTER_MAX_TRANSFER (512 * MiB) 52 53 #define GERR_INDEX_HINT "hint: check in 'server' array index '%d'\n" 54 55 typedef struct GlusterAIOCB { 56 int64_t size; 57 int ret; 58 Coroutine *coroutine; 59 AioContext *aio_context; 60 } GlusterAIOCB; 61 62 typedef struct BDRVGlusterState { 63 struct glfs *glfs; 64 struct glfs_fd *fd; 65 char *logfile; 66 bool supports_seek_data; 67 int debug; 68 } BDRVGlusterState; 69 70 typedef struct BDRVGlusterReopenState { 71 struct glfs *glfs; 72 struct glfs_fd *fd; 73 } BDRVGlusterReopenState; 74 75 76 typedef struct GlfsPreopened { 77 char *volume; 78 glfs_t *fs; 79 int ref; 80 } GlfsPreopened; 81 82 typedef struct ListElement { 83 QLIST_ENTRY(ListElement) list; 84 GlfsPreopened saved; 85 } ListElement; 86 87 static QLIST_HEAD(, ListElement) glfs_list; 88 89 static QemuOptsList qemu_gluster_create_opts = { 90 .name = "qemu-gluster-create-opts", 91 .head = QTAILQ_HEAD_INITIALIZER(qemu_gluster_create_opts.head), 92 .desc = { 93 { 94 .name = BLOCK_OPT_SIZE, 95 .type = QEMU_OPT_SIZE, 96 .help = "Virtual disk size" 97 }, 98 { 99 .name = BLOCK_OPT_PREALLOC, 100 .type = QEMU_OPT_STRING, 101 .help = "Preallocation mode (allowed values: off" 102 #ifdef CONFIG_GLUSTERFS_FALLOCATE 103 ", falloc" 104 #endif 105 #ifdef CONFIG_GLUSTERFS_ZEROFILL 106 ", full" 107 #endif 108 ")" 109 }, 110 { 111 .name = GLUSTER_OPT_DEBUG, 112 .type = QEMU_OPT_NUMBER, 113 .help = "Gluster log level, valid range is 0-9", 114 }, 115 { 116 .name = GLUSTER_OPT_LOGFILE, 117 .type = QEMU_OPT_STRING, 118 .help = "Logfile path of libgfapi", 119 }, 120 { /* end of list */ } 121 } 122 }; 123 124 static QemuOptsList runtime_opts = { 125 .name = "gluster", 126 .head = QTAILQ_HEAD_INITIALIZER(runtime_opts.head), 127 .desc = { 128 { 129 .name = GLUSTER_OPT_FILENAME, 130 .type = QEMU_OPT_STRING, 131 .help = "URL to the gluster image", 132 }, 133 { 134 .name = GLUSTER_OPT_DEBUG, 135 .type = QEMU_OPT_NUMBER, 136 .help = "Gluster log level, valid range is 0-9", 137 }, 138 { 139 .name = GLUSTER_OPT_LOGFILE, 140 .type = QEMU_OPT_STRING, 141 .help = "Logfile path of libgfapi", 142 }, 143 { /* end of list */ } 144 }, 145 }; 146 147 static QemuOptsList runtime_json_opts = { 148 .name = "gluster_json", 149 .head = QTAILQ_HEAD_INITIALIZER(runtime_json_opts.head), 150 .desc = { 151 { 152 .name = GLUSTER_OPT_VOLUME, 153 .type = QEMU_OPT_STRING, 154 .help = "name of gluster volume where VM image resides", 155 }, 156 { 157 .name = GLUSTER_OPT_PATH, 158 .type = QEMU_OPT_STRING, 159 .help = "absolute path to image file in gluster volume", 160 }, 161 { 162 .name = GLUSTER_OPT_DEBUG, 163 .type = QEMU_OPT_NUMBER, 164 .help = "Gluster log level, valid range is 0-9", 165 }, 166 { /* end of list */ } 167 }, 168 }; 169 170 static QemuOptsList runtime_type_opts = { 171 .name = "gluster_type", 172 .head = QTAILQ_HEAD_INITIALIZER(runtime_type_opts.head), 173 .desc = { 174 { 175 .name = GLUSTER_OPT_TYPE, 176 .type = QEMU_OPT_STRING, 177 .help = "inet|unix", 178 }, 179 { /* end of list */ } 180 }, 181 }; 182 183 static QemuOptsList runtime_unix_opts = { 184 .name = "gluster_unix", 185 .head = QTAILQ_HEAD_INITIALIZER(runtime_unix_opts.head), 186 .desc = { 187 { 188 .name = GLUSTER_OPT_SOCKET, 189 .type = QEMU_OPT_STRING, 190 .help = "socket file path (legacy)", 191 }, 192 { 193 .name = GLUSTER_OPT_PATH, 194 .type = QEMU_OPT_STRING, 195 .help = "socket file path (QAPI)", 196 }, 197 { /* end of list */ } 198 }, 199 }; 200 201 static QemuOptsList runtime_inet_opts = { 202 .name = "gluster_inet", 203 .head = QTAILQ_HEAD_INITIALIZER(runtime_inet_opts.head), 204 .desc = { 205 { 206 .name = GLUSTER_OPT_TYPE, 207 .type = QEMU_OPT_STRING, 208 .help = "inet|unix", 209 }, 210 { 211 .name = GLUSTER_OPT_HOST, 212 .type = QEMU_OPT_STRING, 213 .help = "host address (hostname/ipv4/ipv6 addresses)", 214 }, 215 { 216 .name = GLUSTER_OPT_PORT, 217 .type = QEMU_OPT_STRING, 218 .help = "port number on which glusterd is listening (default 24007)", 219 }, 220 { 221 .name = "to", 222 .type = QEMU_OPT_NUMBER, 223 .help = "max port number, not supported by gluster", 224 }, 225 { 226 .name = "ipv4", 227 .type = QEMU_OPT_BOOL, 228 .help = "ipv4 bool value, not supported by gluster", 229 }, 230 { 231 .name = "ipv6", 232 .type = QEMU_OPT_BOOL, 233 .help = "ipv6 bool value, not supported by gluster", 234 }, 235 { /* end of list */ } 236 }, 237 }; 238 239 static void glfs_set_preopened(const char *volume, glfs_t *fs) 240 { 241 ListElement *entry = NULL; 242 243 entry = g_new(ListElement, 1); 244 245 entry->saved.volume = g_strdup(volume); 246 247 entry->saved.fs = fs; 248 entry->saved.ref = 1; 249 250 QLIST_INSERT_HEAD(&glfs_list, entry, list); 251 } 252 253 static glfs_t *glfs_find_preopened(const char *volume) 254 { 255 ListElement *entry = NULL; 256 257 QLIST_FOREACH(entry, &glfs_list, list) { 258 if (strcmp(entry->saved.volume, volume) == 0) { 259 entry->saved.ref++; 260 return entry->saved.fs; 261 } 262 } 263 264 return NULL; 265 } 266 267 static void glfs_clear_preopened(glfs_t *fs) 268 { 269 ListElement *entry = NULL; 270 ListElement *next; 271 272 if (fs == NULL) { 273 return; 274 } 275 276 QLIST_FOREACH_SAFE(entry, &glfs_list, list, next) { 277 if (entry->saved.fs == fs) { 278 if (--entry->saved.ref) { 279 return; 280 } 281 282 QLIST_REMOVE(entry, list); 283 284 glfs_fini(entry->saved.fs); 285 g_free(entry->saved.volume); 286 g_free(entry); 287 } 288 } 289 } 290 291 static int parse_volume_options(BlockdevOptionsGluster *gconf, char *path) 292 { 293 char *p, *q; 294 295 if (!path) { 296 return -EINVAL; 297 } 298 299 /* volume */ 300 p = q = path + strspn(path, "/"); 301 p += strcspn(p, "/"); 302 if (*p == '\0') { 303 return -EINVAL; 304 } 305 gconf->volume = g_strndup(q, p - q); 306 307 /* path */ 308 p += strspn(p, "/"); 309 if (*p == '\0') { 310 return -EINVAL; 311 } 312 gconf->path = g_strdup(p); 313 return 0; 314 } 315 316 /* 317 * file=gluster[+transport]://[host[:port]]/volume/path[?socket=...] 318 * 319 * 'gluster' is the protocol. 320 * 321 * 'transport' specifies the transport type used to connect to gluster 322 * management daemon (glusterd). Valid transport types are 323 * tcp or unix. If a transport type isn't specified, then tcp type is assumed. 324 * 325 * 'host' specifies the host where the volume file specification for 326 * the given volume resides. This can be either hostname or ipv4 address. 327 * If transport type is 'unix', then 'host' field should not be specified. 328 * The 'socket' field needs to be populated with the path to unix domain 329 * socket. 330 * 331 * 'port' is the port number on which glusterd is listening. This is optional 332 * and if not specified, QEMU will send 0 which will make gluster to use the 333 * default port. If the transport type is unix, then 'port' should not be 334 * specified. 335 * 336 * 'volume' is the name of the gluster volume which contains the VM image. 337 * 338 * 'path' is the path to the actual VM image that resides on gluster volume. 339 * 340 * Examples: 341 * 342 * file=gluster://1.2.3.4/testvol/a.img 343 * file=gluster+tcp://1.2.3.4/testvol/a.img 344 * file=gluster+tcp://1.2.3.4:24007/testvol/dir/a.img 345 * file=gluster+tcp://host.domain.com:24007/testvol/dir/a.img 346 * file=gluster+unix:///testvol/dir/a.img?socket=/tmp/glusterd.socket 347 */ 348 static int qemu_gluster_parse_uri(BlockdevOptionsGluster *gconf, 349 const char *filename) 350 { 351 SocketAddress *gsconf; 352 URI *uri; 353 QueryParams *qp = NULL; 354 bool is_unix = false; 355 int ret = 0; 356 357 uri = uri_parse(filename); 358 if (!uri) { 359 return -EINVAL; 360 } 361 362 gconf->server = g_new0(SocketAddressList, 1); 363 gconf->server->value = gsconf = g_new0(SocketAddress, 1); 364 365 /* transport */ 366 if (!uri->scheme || !strcmp(uri->scheme, "gluster")) { 367 gsconf->type = SOCKET_ADDRESS_TYPE_INET; 368 } else if (!strcmp(uri->scheme, "gluster+tcp")) { 369 gsconf->type = SOCKET_ADDRESS_TYPE_INET; 370 } else if (!strcmp(uri->scheme, "gluster+unix")) { 371 gsconf->type = SOCKET_ADDRESS_TYPE_UNIX; 372 is_unix = true; 373 } else if (!strcmp(uri->scheme, "gluster+rdma")) { 374 gsconf->type = SOCKET_ADDRESS_TYPE_INET; 375 warn_report("rdma feature is not supported, falling back to tcp"); 376 } else { 377 ret = -EINVAL; 378 goto out; 379 } 380 381 ret = parse_volume_options(gconf, uri->path); 382 if (ret < 0) { 383 goto out; 384 } 385 386 qp = query_params_parse(uri->query); 387 if (qp->n > 1 || (is_unix && !qp->n) || (!is_unix && qp->n)) { 388 ret = -EINVAL; 389 goto out; 390 } 391 392 if (is_unix) { 393 if (uri->server || uri->port) { 394 ret = -EINVAL; 395 goto out; 396 } 397 if (strcmp(qp->p[0].name, "socket")) { 398 ret = -EINVAL; 399 goto out; 400 } 401 gsconf->u.q_unix.path = g_strdup(qp->p[0].value); 402 } else { 403 gsconf->u.inet.host = g_strdup(uri->server ? uri->server : "localhost"); 404 if (uri->port) { 405 gsconf->u.inet.port = g_strdup_printf("%d", uri->port); 406 } else { 407 gsconf->u.inet.port = g_strdup_printf("%d", GLUSTER_DEFAULT_PORT); 408 } 409 } 410 411 out: 412 if (qp) { 413 query_params_free(qp); 414 } 415 uri_free(uri); 416 return ret; 417 } 418 419 static struct glfs *qemu_gluster_glfs_init(BlockdevOptionsGluster *gconf, 420 Error **errp) 421 { 422 struct glfs *glfs; 423 int ret; 424 int old_errno; 425 SocketAddressList *server; 426 unsigned long long port; 427 428 glfs = glfs_find_preopened(gconf->volume); 429 if (glfs) { 430 return glfs; 431 } 432 433 glfs = glfs_new(gconf->volume); 434 if (!glfs) { 435 goto out; 436 } 437 438 glfs_set_preopened(gconf->volume, glfs); 439 440 for (server = gconf->server; server; server = server->next) { 441 switch (server->value->type) { 442 case SOCKET_ADDRESS_TYPE_UNIX: 443 ret = glfs_set_volfile_server(glfs, "unix", 444 server->value->u.q_unix.path, 0); 445 break; 446 case SOCKET_ADDRESS_TYPE_INET: 447 if (parse_uint_full(server->value->u.inet.port, &port, 10) < 0 || 448 port > 65535) { 449 error_setg(errp, "'%s' is not a valid port number", 450 server->value->u.inet.port); 451 errno = EINVAL; 452 goto out; 453 } 454 ret = glfs_set_volfile_server(glfs, "tcp", 455 server->value->u.inet.host, 456 (int)port); 457 break; 458 case SOCKET_ADDRESS_TYPE_VSOCK: 459 case SOCKET_ADDRESS_TYPE_FD: 460 default: 461 abort(); 462 } 463 464 if (ret < 0) { 465 goto out; 466 } 467 } 468 469 ret = glfs_set_logging(glfs, gconf->logfile, gconf->debug); 470 if (ret < 0) { 471 goto out; 472 } 473 474 ret = glfs_init(glfs); 475 if (ret) { 476 error_setg(errp, "Gluster connection for volume %s, path %s failed" 477 " to connect", gconf->volume, gconf->path); 478 for (server = gconf->server; server; server = server->next) { 479 if (server->value->type == SOCKET_ADDRESS_TYPE_UNIX) { 480 error_append_hint(errp, "hint: failed on socket %s ", 481 server->value->u.q_unix.path); 482 } else { 483 error_append_hint(errp, "hint: failed on host %s and port %s ", 484 server->value->u.inet.host, 485 server->value->u.inet.port); 486 } 487 } 488 489 error_append_hint(errp, "Please refer to gluster logs for more info\n"); 490 491 /* glfs_init sometimes doesn't set errno although docs suggest that */ 492 if (errno == 0) { 493 errno = EINVAL; 494 } 495 496 goto out; 497 } 498 return glfs; 499 500 out: 501 if (glfs) { 502 old_errno = errno; 503 glfs_clear_preopened(glfs); 504 errno = old_errno; 505 } 506 return NULL; 507 } 508 509 /* 510 * Convert the json formatted command line into qapi. 511 */ 512 static int qemu_gluster_parse_json(BlockdevOptionsGluster *gconf, 513 QDict *options, Error **errp) 514 { 515 QemuOpts *opts; 516 SocketAddress *gsconf = NULL; 517 SocketAddressList *curr = NULL; 518 QDict *backing_options = NULL; 519 Error *local_err = NULL; 520 char *str = NULL; 521 const char *ptr; 522 int i, type, num_servers; 523 524 /* create opts info from runtime_json_opts list */ 525 opts = qemu_opts_create(&runtime_json_opts, NULL, 0, &error_abort); 526 if (!qemu_opts_absorb_qdict(opts, options, errp)) { 527 goto out; 528 } 529 530 num_servers = qdict_array_entries(options, GLUSTER_OPT_SERVER_PATTERN); 531 if (num_servers < 1) { 532 error_setg(&local_err, QERR_MISSING_PARAMETER, "server"); 533 goto out; 534 } 535 536 ptr = qemu_opt_get(opts, GLUSTER_OPT_VOLUME); 537 if (!ptr) { 538 error_setg(&local_err, QERR_MISSING_PARAMETER, GLUSTER_OPT_VOLUME); 539 goto out; 540 } 541 gconf->volume = g_strdup(ptr); 542 543 ptr = qemu_opt_get(opts, GLUSTER_OPT_PATH); 544 if (!ptr) { 545 error_setg(&local_err, QERR_MISSING_PARAMETER, GLUSTER_OPT_PATH); 546 goto out; 547 } 548 gconf->path = g_strdup(ptr); 549 qemu_opts_del(opts); 550 551 for (i = 0; i < num_servers; i++) { 552 str = g_strdup_printf(GLUSTER_OPT_SERVER_PATTERN"%d.", i); 553 qdict_extract_subqdict(options, &backing_options, str); 554 555 /* create opts info from runtime_type_opts list */ 556 opts = qemu_opts_create(&runtime_type_opts, NULL, 0, &error_abort); 557 if (!qemu_opts_absorb_qdict(opts, backing_options, errp)) { 558 goto out; 559 } 560 561 ptr = qemu_opt_get(opts, GLUSTER_OPT_TYPE); 562 if (!ptr) { 563 error_setg(&local_err, QERR_MISSING_PARAMETER, GLUSTER_OPT_TYPE); 564 error_append_hint(&local_err, GERR_INDEX_HINT, i); 565 goto out; 566 567 } 568 gsconf = g_new0(SocketAddress, 1); 569 if (!strcmp(ptr, "tcp")) { 570 ptr = "inet"; /* accept legacy "tcp" */ 571 } 572 type = qapi_enum_parse(&SocketAddressType_lookup, ptr, -1, NULL); 573 if (type != SOCKET_ADDRESS_TYPE_INET 574 && type != SOCKET_ADDRESS_TYPE_UNIX) { 575 error_setg(&local_err, 576 "Parameter '%s' may be 'inet' or 'unix'", 577 GLUSTER_OPT_TYPE); 578 error_append_hint(&local_err, GERR_INDEX_HINT, i); 579 goto out; 580 } 581 gsconf->type = type; 582 qemu_opts_del(opts); 583 584 if (gsconf->type == SOCKET_ADDRESS_TYPE_INET) { 585 /* create opts info from runtime_inet_opts list */ 586 opts = qemu_opts_create(&runtime_inet_opts, NULL, 0, &error_abort); 587 if (!qemu_opts_absorb_qdict(opts, backing_options, errp)) { 588 goto out; 589 } 590 591 ptr = qemu_opt_get(opts, GLUSTER_OPT_HOST); 592 if (!ptr) { 593 error_setg(&local_err, QERR_MISSING_PARAMETER, 594 GLUSTER_OPT_HOST); 595 error_append_hint(&local_err, GERR_INDEX_HINT, i); 596 goto out; 597 } 598 gsconf->u.inet.host = g_strdup(ptr); 599 ptr = qemu_opt_get(opts, GLUSTER_OPT_PORT); 600 if (!ptr) { 601 error_setg(&local_err, QERR_MISSING_PARAMETER, 602 GLUSTER_OPT_PORT); 603 error_append_hint(&local_err, GERR_INDEX_HINT, i); 604 goto out; 605 } 606 gsconf->u.inet.port = g_strdup(ptr); 607 608 /* defend for unsupported fields in InetSocketAddress, 609 * i.e. @ipv4, @ipv6 and @to 610 */ 611 ptr = qemu_opt_get(opts, GLUSTER_OPT_TO); 612 if (ptr) { 613 gsconf->u.inet.has_to = true; 614 } 615 ptr = qemu_opt_get(opts, GLUSTER_OPT_IPV4); 616 if (ptr) { 617 gsconf->u.inet.has_ipv4 = true; 618 } 619 ptr = qemu_opt_get(opts, GLUSTER_OPT_IPV6); 620 if (ptr) { 621 gsconf->u.inet.has_ipv6 = true; 622 } 623 if (gsconf->u.inet.has_to) { 624 error_setg(&local_err, "Parameter 'to' not supported"); 625 goto out; 626 } 627 if (gsconf->u.inet.has_ipv4 || gsconf->u.inet.has_ipv6) { 628 error_setg(&local_err, "Parameters 'ipv4/ipv6' not supported"); 629 goto out; 630 } 631 qemu_opts_del(opts); 632 } else { 633 /* create opts info from runtime_unix_opts list */ 634 opts = qemu_opts_create(&runtime_unix_opts, NULL, 0, &error_abort); 635 if (!qemu_opts_absorb_qdict(opts, backing_options, errp)) { 636 goto out; 637 } 638 639 ptr = qemu_opt_get(opts, GLUSTER_OPT_PATH); 640 if (!ptr) { 641 ptr = qemu_opt_get(opts, GLUSTER_OPT_SOCKET); 642 } else if (qemu_opt_get(opts, GLUSTER_OPT_SOCKET)) { 643 error_setg(&local_err, 644 "Conflicting parameters 'path' and 'socket'"); 645 error_append_hint(&local_err, GERR_INDEX_HINT, i); 646 goto out; 647 } 648 if (!ptr) { 649 error_setg(&local_err, QERR_MISSING_PARAMETER, 650 GLUSTER_OPT_PATH); 651 error_append_hint(&local_err, GERR_INDEX_HINT, i); 652 goto out; 653 } 654 gsconf->u.q_unix.path = g_strdup(ptr); 655 qemu_opts_del(opts); 656 } 657 658 if (gconf->server == NULL) { 659 gconf->server = g_new0(SocketAddressList, 1); 660 gconf->server->value = gsconf; 661 curr = gconf->server; 662 } else { 663 curr->next = g_new0(SocketAddressList, 1); 664 curr->next->value = gsconf; 665 curr = curr->next; 666 } 667 gsconf = NULL; 668 669 qobject_unref(backing_options); 670 backing_options = NULL; 671 g_free(str); 672 str = NULL; 673 } 674 675 return 0; 676 677 out: 678 error_propagate(errp, local_err); 679 qapi_free_SocketAddress(gsconf); 680 qemu_opts_del(opts); 681 g_free(str); 682 qobject_unref(backing_options); 683 errno = EINVAL; 684 return -errno; 685 } 686 687 /* Converts options given in @filename and the @options QDict into the QAPI 688 * object @gconf. */ 689 static int qemu_gluster_parse(BlockdevOptionsGluster *gconf, 690 const char *filename, 691 QDict *options, Error **errp) 692 { 693 int ret; 694 if (filename) { 695 ret = qemu_gluster_parse_uri(gconf, filename); 696 if (ret < 0) { 697 error_setg(errp, "invalid URI %s", filename); 698 error_append_hint(errp, "Usage: file=gluster[+transport]://" 699 "[host[:port]]volume/path[?socket=...]" 700 "[,file.debug=N]" 701 "[,file.logfile=/path/filename.log]\n"); 702 return ret; 703 } 704 } else { 705 ret = qemu_gluster_parse_json(gconf, options, errp); 706 if (ret < 0) { 707 error_append_hint(errp, "Usage: " 708 "-drive driver=qcow2,file.driver=gluster," 709 "file.volume=testvol,file.path=/path/a.qcow2" 710 "[,file.debug=9]" 711 "[,file.logfile=/path/filename.log]," 712 "file.server.0.type=inet," 713 "file.server.0.host=1.2.3.4," 714 "file.server.0.port=24007," 715 "file.server.1.transport=unix," 716 "file.server.1.path=/var/run/glusterd.socket ..." 717 "\n"); 718 return ret; 719 } 720 } 721 722 return 0; 723 } 724 725 static struct glfs *qemu_gluster_init(BlockdevOptionsGluster *gconf, 726 const char *filename, 727 QDict *options, Error **errp) 728 { 729 int ret; 730 731 ret = qemu_gluster_parse(gconf, filename, options, errp); 732 if (ret < 0) { 733 errno = -ret; 734 return NULL; 735 } 736 737 return qemu_gluster_glfs_init(gconf, errp); 738 } 739 740 /* 741 * AIO callback routine called from GlusterFS thread. 742 */ 743 static void gluster_finish_aiocb(struct glfs_fd *fd, ssize_t ret, 744 #ifdef CONFIG_GLUSTERFS_IOCB_HAS_STAT 745 struct glfs_stat *pre, struct glfs_stat *post, 746 #endif 747 void *arg) 748 { 749 GlusterAIOCB *acb = (GlusterAIOCB *)arg; 750 751 if (!ret || ret == acb->size) { 752 acb->ret = 0; /* Success */ 753 } else if (ret < 0) { 754 acb->ret = -errno; /* Read/Write failed */ 755 } else { 756 acb->ret = -EIO; /* Partial read/write - fail it */ 757 } 758 759 aio_co_schedule(acb->aio_context, acb->coroutine); 760 } 761 762 static void qemu_gluster_parse_flags(int bdrv_flags, int *open_flags) 763 { 764 assert(open_flags != NULL); 765 766 *open_flags |= O_BINARY; 767 768 if (bdrv_flags & BDRV_O_RDWR) { 769 *open_flags |= O_RDWR; 770 } else { 771 *open_flags |= O_RDONLY; 772 } 773 774 if ((bdrv_flags & BDRV_O_NOCACHE)) { 775 *open_flags |= O_DIRECT; 776 } 777 } 778 779 /* 780 * Do SEEK_DATA/HOLE to detect if it is functional. Older broken versions of 781 * gfapi incorrectly return the current offset when SEEK_DATA/HOLE is used. 782 * - Corrected versions return -1 and set errno to EINVAL. 783 * - Versions that support SEEK_DATA/HOLE correctly, will return -1 and set 784 * errno to ENXIO when SEEK_DATA is called with a position of EOF. 785 */ 786 static bool qemu_gluster_test_seek(struct glfs_fd *fd) 787 { 788 off_t ret = 0; 789 790 #if defined SEEK_HOLE && defined SEEK_DATA 791 off_t eof; 792 793 eof = glfs_lseek(fd, 0, SEEK_END); 794 if (eof < 0) { 795 /* this should never occur */ 796 return false; 797 } 798 799 /* this should always fail with ENXIO if SEEK_DATA is supported */ 800 ret = glfs_lseek(fd, eof, SEEK_DATA); 801 #endif 802 803 return (ret < 0) && (errno == ENXIO); 804 } 805 806 static int qemu_gluster_open(BlockDriverState *bs, QDict *options, 807 int bdrv_flags, Error **errp) 808 { 809 BDRVGlusterState *s = bs->opaque; 810 int open_flags = 0; 811 int ret = 0; 812 BlockdevOptionsGluster *gconf = NULL; 813 QemuOpts *opts; 814 const char *filename, *logfile; 815 816 opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort); 817 if (!qemu_opts_absorb_qdict(opts, options, errp)) { 818 ret = -EINVAL; 819 goto out; 820 } 821 822 filename = qemu_opt_get(opts, GLUSTER_OPT_FILENAME); 823 824 s->debug = qemu_opt_get_number(opts, GLUSTER_OPT_DEBUG, 825 GLUSTER_DEBUG_DEFAULT); 826 if (s->debug < 0) { 827 s->debug = 0; 828 } else if (s->debug > GLUSTER_DEBUG_MAX) { 829 s->debug = GLUSTER_DEBUG_MAX; 830 } 831 832 gconf = g_new0(BlockdevOptionsGluster, 1); 833 gconf->debug = s->debug; 834 gconf->has_debug = true; 835 836 logfile = qemu_opt_get(opts, GLUSTER_OPT_LOGFILE); 837 s->logfile = g_strdup(logfile ? logfile : GLUSTER_LOGFILE_DEFAULT); 838 839 gconf->logfile = g_strdup(s->logfile); 840 gconf->has_logfile = true; 841 842 s->glfs = qemu_gluster_init(gconf, filename, options, errp); 843 if (!s->glfs) { 844 ret = -errno; 845 goto out; 846 } 847 848 #ifdef CONFIG_GLUSTERFS_XLATOR_OPT 849 /* Without this, if fsync fails for a recoverable reason (for instance, 850 * ENOSPC), gluster will dump its cache, preventing retries. This means 851 * almost certain data loss. Not all gluster versions support the 852 * 'resync-failed-syncs-after-fsync' key value, but there is no way to 853 * discover during runtime if it is supported (this api returns success for 854 * unknown key/value pairs) */ 855 ret = glfs_set_xlator_option(s->glfs, "*-write-behind", 856 "resync-failed-syncs-after-fsync", 857 "on"); 858 if (ret < 0) { 859 error_setg_errno(errp, errno, "Unable to set xlator key/value pair"); 860 ret = -errno; 861 goto out; 862 } 863 #endif 864 865 qemu_gluster_parse_flags(bdrv_flags, &open_flags); 866 867 s->fd = glfs_open(s->glfs, gconf->path, open_flags); 868 ret = s->fd ? 0 : -errno; 869 870 if (ret == -EACCES || ret == -EROFS) { 871 /* Try to degrade to read-only, but if it doesn't work, still use the 872 * normal error message. */ 873 if (bdrv_apply_auto_read_only(bs, NULL, NULL) == 0) { 874 open_flags = (open_flags & ~O_RDWR) | O_RDONLY; 875 s->fd = glfs_open(s->glfs, gconf->path, open_flags); 876 ret = s->fd ? 0 : -errno; 877 } 878 } 879 880 s->supports_seek_data = qemu_gluster_test_seek(s->fd); 881 882 out: 883 qemu_opts_del(opts); 884 qapi_free_BlockdevOptionsGluster(gconf); 885 if (!ret) { 886 return ret; 887 } 888 g_free(s->logfile); 889 if (s->fd) { 890 glfs_close(s->fd); 891 } 892 893 glfs_clear_preopened(s->glfs); 894 895 return ret; 896 } 897 898 static void qemu_gluster_refresh_limits(BlockDriverState *bs, Error **errp) 899 { 900 bs->bl.max_transfer = GLUSTER_MAX_TRANSFER; 901 } 902 903 static int qemu_gluster_reopen_prepare(BDRVReopenState *state, 904 BlockReopenQueue *queue, Error **errp) 905 { 906 int ret = 0; 907 BDRVGlusterState *s; 908 BDRVGlusterReopenState *reop_s; 909 BlockdevOptionsGluster *gconf; 910 int open_flags = 0; 911 912 assert(state != NULL); 913 assert(state->bs != NULL); 914 915 s = state->bs->opaque; 916 917 state->opaque = g_new0(BDRVGlusterReopenState, 1); 918 reop_s = state->opaque; 919 920 qemu_gluster_parse_flags(state->flags, &open_flags); 921 922 gconf = g_new0(BlockdevOptionsGluster, 1); 923 gconf->debug = s->debug; 924 gconf->has_debug = true; 925 gconf->logfile = g_strdup(s->logfile); 926 gconf->has_logfile = true; 927 928 /* 929 * If 'state->bs->exact_filename' is empty, 'state->options' should contain 930 * the JSON parameters already parsed. 931 */ 932 if (state->bs->exact_filename[0] != '\0') { 933 reop_s->glfs = qemu_gluster_init(gconf, state->bs->exact_filename, NULL, 934 errp); 935 } else { 936 reop_s->glfs = qemu_gluster_init(gconf, NULL, state->options, errp); 937 } 938 if (reop_s->glfs == NULL) { 939 ret = -errno; 940 goto exit; 941 } 942 943 #ifdef CONFIG_GLUSTERFS_XLATOR_OPT 944 ret = glfs_set_xlator_option(reop_s->glfs, "*-write-behind", 945 "resync-failed-syncs-after-fsync", "on"); 946 if (ret < 0) { 947 error_setg_errno(errp, errno, "Unable to set xlator key/value pair"); 948 ret = -errno; 949 goto exit; 950 } 951 #endif 952 953 reop_s->fd = glfs_open(reop_s->glfs, gconf->path, open_flags); 954 if (reop_s->fd == NULL) { 955 /* reops->glfs will be cleaned up in _abort */ 956 ret = -errno; 957 goto exit; 958 } 959 960 exit: 961 /* state->opaque will be freed in either the _abort or _commit */ 962 qapi_free_BlockdevOptionsGluster(gconf); 963 return ret; 964 } 965 966 static void qemu_gluster_reopen_commit(BDRVReopenState *state) 967 { 968 BDRVGlusterReopenState *reop_s = state->opaque; 969 BDRVGlusterState *s = state->bs->opaque; 970 971 972 /* close the old */ 973 if (s->fd) { 974 glfs_close(s->fd); 975 } 976 977 glfs_clear_preopened(s->glfs); 978 979 /* use the newly opened image / connection */ 980 s->fd = reop_s->fd; 981 s->glfs = reop_s->glfs; 982 983 g_free(state->opaque); 984 state->opaque = NULL; 985 986 return; 987 } 988 989 990 static void qemu_gluster_reopen_abort(BDRVReopenState *state) 991 { 992 BDRVGlusterReopenState *reop_s = state->opaque; 993 994 if (reop_s == NULL) { 995 return; 996 } 997 998 if (reop_s->fd) { 999 glfs_close(reop_s->fd); 1000 } 1001 1002 glfs_clear_preopened(reop_s->glfs); 1003 1004 g_free(state->opaque); 1005 state->opaque = NULL; 1006 1007 return; 1008 } 1009 1010 #ifdef CONFIG_GLUSTERFS_ZEROFILL 1011 static coroutine_fn int qemu_gluster_co_pwrite_zeroes(BlockDriverState *bs, 1012 int64_t offset, 1013 int size, 1014 BdrvRequestFlags flags) 1015 { 1016 int ret; 1017 GlusterAIOCB acb; 1018 BDRVGlusterState *s = bs->opaque; 1019 1020 acb.size = size; 1021 acb.ret = 0; 1022 acb.coroutine = qemu_coroutine_self(); 1023 acb.aio_context = bdrv_get_aio_context(bs); 1024 1025 ret = glfs_zerofill_async(s->fd, offset, size, gluster_finish_aiocb, &acb); 1026 if (ret < 0) { 1027 return -errno; 1028 } 1029 1030 qemu_coroutine_yield(); 1031 return acb.ret; 1032 } 1033 #endif 1034 1035 static int qemu_gluster_do_truncate(struct glfs_fd *fd, int64_t offset, 1036 PreallocMode prealloc, Error **errp) 1037 { 1038 int64_t current_length; 1039 1040 current_length = glfs_lseek(fd, 0, SEEK_END); 1041 if (current_length < 0) { 1042 error_setg_errno(errp, errno, "Failed to determine current size"); 1043 return -errno; 1044 } 1045 1046 if (current_length > offset && prealloc != PREALLOC_MODE_OFF) { 1047 error_setg(errp, "Cannot use preallocation for shrinking files"); 1048 return -ENOTSUP; 1049 } 1050 1051 if (current_length == offset) { 1052 return 0; 1053 } 1054 1055 switch (prealloc) { 1056 #ifdef CONFIG_GLUSTERFS_FALLOCATE 1057 case PREALLOC_MODE_FALLOC: 1058 if (glfs_fallocate(fd, 0, current_length, offset - current_length)) { 1059 error_setg_errno(errp, errno, "Could not preallocate data"); 1060 return -errno; 1061 } 1062 break; 1063 #endif /* CONFIG_GLUSTERFS_FALLOCATE */ 1064 #ifdef CONFIG_GLUSTERFS_ZEROFILL 1065 case PREALLOC_MODE_FULL: 1066 if (glfs_ftruncate(fd, offset)) { 1067 error_setg_errno(errp, errno, "Could not resize file"); 1068 return -errno; 1069 } 1070 if (glfs_zerofill(fd, current_length, offset - current_length)) { 1071 error_setg_errno(errp, errno, "Could not zerofill the new area"); 1072 return -errno; 1073 } 1074 break; 1075 #endif /* CONFIG_GLUSTERFS_ZEROFILL */ 1076 case PREALLOC_MODE_OFF: 1077 if (glfs_ftruncate(fd, offset)) { 1078 error_setg_errno(errp, errno, "Could not resize file"); 1079 return -errno; 1080 } 1081 break; 1082 default: 1083 error_setg(errp, "Unsupported preallocation mode: %s", 1084 PreallocMode_str(prealloc)); 1085 return -EINVAL; 1086 } 1087 1088 return 0; 1089 } 1090 1091 static int qemu_gluster_co_create(BlockdevCreateOptions *options, 1092 Error **errp) 1093 { 1094 BlockdevCreateOptionsGluster *opts = &options->u.gluster; 1095 struct glfs *glfs; 1096 struct glfs_fd *fd = NULL; 1097 int ret = 0; 1098 1099 assert(options->driver == BLOCKDEV_DRIVER_GLUSTER); 1100 1101 glfs = qemu_gluster_glfs_init(opts->location, errp); 1102 if (!glfs) { 1103 ret = -errno; 1104 goto out; 1105 } 1106 1107 fd = glfs_creat(glfs, opts->location->path, 1108 O_WRONLY | O_CREAT | O_TRUNC | O_BINARY, S_IRUSR | S_IWUSR); 1109 if (!fd) { 1110 ret = -errno; 1111 goto out; 1112 } 1113 1114 ret = qemu_gluster_do_truncate(fd, opts->size, opts->preallocation, errp); 1115 1116 out: 1117 if (fd) { 1118 if (glfs_close(fd) != 0 && ret == 0) { 1119 ret = -errno; 1120 } 1121 } 1122 glfs_clear_preopened(glfs); 1123 return ret; 1124 } 1125 1126 static int coroutine_fn qemu_gluster_co_create_opts(BlockDriver *drv, 1127 const char *filename, 1128 QemuOpts *opts, 1129 Error **errp) 1130 { 1131 BlockdevCreateOptions *options; 1132 BlockdevCreateOptionsGluster *gopts; 1133 BlockdevOptionsGluster *gconf; 1134 char *tmp = NULL; 1135 Error *local_err = NULL; 1136 int ret; 1137 1138 options = g_new0(BlockdevCreateOptions, 1); 1139 options->driver = BLOCKDEV_DRIVER_GLUSTER; 1140 gopts = &options->u.gluster; 1141 1142 gconf = g_new0(BlockdevOptionsGluster, 1); 1143 gopts->location = gconf; 1144 1145 gopts->size = ROUND_UP(qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0), 1146 BDRV_SECTOR_SIZE); 1147 1148 tmp = qemu_opt_get_del(opts, BLOCK_OPT_PREALLOC); 1149 gopts->preallocation = qapi_enum_parse(&PreallocMode_lookup, tmp, 1150 PREALLOC_MODE_OFF, &local_err); 1151 g_free(tmp); 1152 if (local_err) { 1153 error_propagate(errp, local_err); 1154 ret = -EINVAL; 1155 goto fail; 1156 } 1157 1158 gconf->debug = qemu_opt_get_number_del(opts, GLUSTER_OPT_DEBUG, 1159 GLUSTER_DEBUG_DEFAULT); 1160 if (gconf->debug < 0) { 1161 gconf->debug = 0; 1162 } else if (gconf->debug > GLUSTER_DEBUG_MAX) { 1163 gconf->debug = GLUSTER_DEBUG_MAX; 1164 } 1165 gconf->has_debug = true; 1166 1167 gconf->logfile = qemu_opt_get_del(opts, GLUSTER_OPT_LOGFILE); 1168 if (!gconf->logfile) { 1169 gconf->logfile = g_strdup(GLUSTER_LOGFILE_DEFAULT); 1170 } 1171 gconf->has_logfile = true; 1172 1173 ret = qemu_gluster_parse(gconf, filename, NULL, errp); 1174 if (ret < 0) { 1175 goto fail; 1176 } 1177 1178 ret = qemu_gluster_co_create(options, errp); 1179 if (ret < 0) { 1180 goto fail; 1181 } 1182 1183 ret = 0; 1184 fail: 1185 qapi_free_BlockdevCreateOptions(options); 1186 return ret; 1187 } 1188 1189 static coroutine_fn int qemu_gluster_co_rw(BlockDriverState *bs, 1190 int64_t sector_num, int nb_sectors, 1191 QEMUIOVector *qiov, int write) 1192 { 1193 int ret; 1194 GlusterAIOCB acb; 1195 BDRVGlusterState *s = bs->opaque; 1196 size_t size = nb_sectors * BDRV_SECTOR_SIZE; 1197 off_t offset = sector_num * BDRV_SECTOR_SIZE; 1198 1199 acb.size = size; 1200 acb.ret = 0; 1201 acb.coroutine = qemu_coroutine_self(); 1202 acb.aio_context = bdrv_get_aio_context(bs); 1203 1204 if (write) { 1205 ret = glfs_pwritev_async(s->fd, qiov->iov, qiov->niov, offset, 0, 1206 gluster_finish_aiocb, &acb); 1207 } else { 1208 ret = glfs_preadv_async(s->fd, qiov->iov, qiov->niov, offset, 0, 1209 gluster_finish_aiocb, &acb); 1210 } 1211 1212 if (ret < 0) { 1213 return -errno; 1214 } 1215 1216 qemu_coroutine_yield(); 1217 return acb.ret; 1218 } 1219 1220 static coroutine_fn int qemu_gluster_co_truncate(BlockDriverState *bs, 1221 int64_t offset, 1222 bool exact, 1223 PreallocMode prealloc, 1224 BdrvRequestFlags flags, 1225 Error **errp) 1226 { 1227 BDRVGlusterState *s = bs->opaque; 1228 return qemu_gluster_do_truncate(s->fd, offset, prealloc, errp); 1229 } 1230 1231 static coroutine_fn int qemu_gluster_co_readv(BlockDriverState *bs, 1232 int64_t sector_num, 1233 int nb_sectors, 1234 QEMUIOVector *qiov) 1235 { 1236 return qemu_gluster_co_rw(bs, sector_num, nb_sectors, qiov, 0); 1237 } 1238 1239 static coroutine_fn int qemu_gluster_co_writev(BlockDriverState *bs, 1240 int64_t sector_num, 1241 int nb_sectors, 1242 QEMUIOVector *qiov, 1243 int flags) 1244 { 1245 assert(!flags); 1246 return qemu_gluster_co_rw(bs, sector_num, nb_sectors, qiov, 1); 1247 } 1248 1249 static void qemu_gluster_close(BlockDriverState *bs) 1250 { 1251 BDRVGlusterState *s = bs->opaque; 1252 1253 g_free(s->logfile); 1254 if (s->fd) { 1255 glfs_close(s->fd); 1256 s->fd = NULL; 1257 } 1258 glfs_clear_preopened(s->glfs); 1259 } 1260 1261 static coroutine_fn int qemu_gluster_co_flush_to_disk(BlockDriverState *bs) 1262 { 1263 int ret; 1264 GlusterAIOCB acb; 1265 BDRVGlusterState *s = bs->opaque; 1266 1267 acb.size = 0; 1268 acb.ret = 0; 1269 acb.coroutine = qemu_coroutine_self(); 1270 acb.aio_context = bdrv_get_aio_context(bs); 1271 1272 ret = glfs_fsync_async(s->fd, gluster_finish_aiocb, &acb); 1273 if (ret < 0) { 1274 ret = -errno; 1275 goto error; 1276 } 1277 1278 qemu_coroutine_yield(); 1279 if (acb.ret < 0) { 1280 ret = acb.ret; 1281 goto error; 1282 } 1283 1284 return acb.ret; 1285 1286 error: 1287 /* Some versions of Gluster (3.5.6 -> 3.5.8?) will not retain its cache 1288 * after a fsync failure, so we have no way of allowing the guest to safely 1289 * continue. Gluster versions prior to 3.5.6 don't retain the cache 1290 * either, but will invalidate the fd on error, so this is again our only 1291 * option. 1292 * 1293 * The 'resync-failed-syncs-after-fsync' xlator option for the 1294 * write-behind cache will cause later gluster versions to retain its 1295 * cache after error, so long as the fd remains open. However, we 1296 * currently have no way of knowing if this option is supported. 1297 * 1298 * TODO: Once gluster provides a way for us to determine if the option 1299 * is supported, bypass the closure and setting drv to NULL. */ 1300 qemu_gluster_close(bs); 1301 bs->drv = NULL; 1302 return ret; 1303 } 1304 1305 #ifdef CONFIG_GLUSTERFS_DISCARD 1306 static coroutine_fn int qemu_gluster_co_pdiscard(BlockDriverState *bs, 1307 int64_t offset, int size) 1308 { 1309 int ret; 1310 GlusterAIOCB acb; 1311 BDRVGlusterState *s = bs->opaque; 1312 1313 acb.size = 0; 1314 acb.ret = 0; 1315 acb.coroutine = qemu_coroutine_self(); 1316 acb.aio_context = bdrv_get_aio_context(bs); 1317 1318 ret = glfs_discard_async(s->fd, offset, size, gluster_finish_aiocb, &acb); 1319 if (ret < 0) { 1320 return -errno; 1321 } 1322 1323 qemu_coroutine_yield(); 1324 return acb.ret; 1325 } 1326 #endif 1327 1328 static int64_t qemu_gluster_getlength(BlockDriverState *bs) 1329 { 1330 BDRVGlusterState *s = bs->opaque; 1331 int64_t ret; 1332 1333 ret = glfs_lseek(s->fd, 0, SEEK_END); 1334 if (ret < 0) { 1335 return -errno; 1336 } else { 1337 return ret; 1338 } 1339 } 1340 1341 static int64_t qemu_gluster_allocated_file_size(BlockDriverState *bs) 1342 { 1343 BDRVGlusterState *s = bs->opaque; 1344 struct stat st; 1345 int ret; 1346 1347 ret = glfs_fstat(s->fd, &st); 1348 if (ret < 0) { 1349 return -errno; 1350 } else { 1351 return st.st_blocks * 512; 1352 } 1353 } 1354 1355 /* 1356 * Find allocation range in @bs around offset @start. 1357 * May change underlying file descriptor's file offset. 1358 * If @start is not in a hole, store @start in @data, and the 1359 * beginning of the next hole in @hole, and return 0. 1360 * If @start is in a non-trailing hole, store @start in @hole and the 1361 * beginning of the next non-hole in @data, and return 0. 1362 * If @start is in a trailing hole or beyond EOF, return -ENXIO. 1363 * If we can't find out, return a negative errno other than -ENXIO. 1364 * 1365 * (Shamefully copied from file-posix.c, only minuscule adaptions.) 1366 */ 1367 static int find_allocation(BlockDriverState *bs, off_t start, 1368 off_t *data, off_t *hole) 1369 { 1370 BDRVGlusterState *s = bs->opaque; 1371 1372 if (!s->supports_seek_data) { 1373 goto exit; 1374 } 1375 1376 #if defined SEEK_HOLE && defined SEEK_DATA 1377 off_t offs; 1378 1379 /* 1380 * SEEK_DATA cases: 1381 * D1. offs == start: start is in data 1382 * D2. offs > start: start is in a hole, next data at offs 1383 * D3. offs < 0, errno = ENXIO: either start is in a trailing hole 1384 * or start is beyond EOF 1385 * If the latter happens, the file has been truncated behind 1386 * our back since we opened it. All bets are off then. 1387 * Treating like a trailing hole is simplest. 1388 * D4. offs < 0, errno != ENXIO: we learned nothing 1389 */ 1390 offs = glfs_lseek(s->fd, start, SEEK_DATA); 1391 if (offs < 0) { 1392 return -errno; /* D3 or D4 */ 1393 } 1394 1395 if (offs < start) { 1396 /* This is not a valid return by lseek(). We are safe to just return 1397 * -EIO in this case, and we'll treat it like D4. Unfortunately some 1398 * versions of gluster server will return offs < start, so an assert 1399 * here will unnecessarily abort QEMU. */ 1400 return -EIO; 1401 } 1402 1403 if (offs > start) { 1404 /* D2: in hole, next data at offs */ 1405 *hole = start; 1406 *data = offs; 1407 return 0; 1408 } 1409 1410 /* D1: in data, end not yet known */ 1411 1412 /* 1413 * SEEK_HOLE cases: 1414 * H1. offs == start: start is in a hole 1415 * If this happens here, a hole has been dug behind our back 1416 * since the previous lseek(). 1417 * H2. offs > start: either start is in data, next hole at offs, 1418 * or start is in trailing hole, EOF at offs 1419 * Linux treats trailing holes like any other hole: offs == 1420 * start. Solaris seeks to EOF instead: offs > start (blech). 1421 * If that happens here, a hole has been dug behind our back 1422 * since the previous lseek(). 1423 * H3. offs < 0, errno = ENXIO: start is beyond EOF 1424 * If this happens, the file has been truncated behind our 1425 * back since we opened it. Treat it like a trailing hole. 1426 * H4. offs < 0, errno != ENXIO: we learned nothing 1427 * Pretend we know nothing at all, i.e. "forget" about D1. 1428 */ 1429 offs = glfs_lseek(s->fd, start, SEEK_HOLE); 1430 if (offs < 0) { 1431 return -errno; /* D1 and (H3 or H4) */ 1432 } 1433 1434 if (offs < start) { 1435 /* This is not a valid return by lseek(). We are safe to just return 1436 * -EIO in this case, and we'll treat it like H4. Unfortunately some 1437 * versions of gluster server will return offs < start, so an assert 1438 * here will unnecessarily abort QEMU. */ 1439 return -EIO; 1440 } 1441 1442 if (offs > start) { 1443 /* 1444 * D1 and H2: either in data, next hole at offs, or it was in 1445 * data but is now in a trailing hole. In the latter case, 1446 * all bets are off. Treating it as if it there was data all 1447 * the way to EOF is safe, so simply do that. 1448 */ 1449 *data = start; 1450 *hole = offs; 1451 return 0; 1452 } 1453 1454 /* D1 and H1 */ 1455 return -EBUSY; 1456 #endif 1457 1458 exit: 1459 return -ENOTSUP; 1460 } 1461 1462 /* 1463 * Returns the allocation status of the specified offset. 1464 * 1465 * The block layer guarantees 'offset' and 'bytes' are within bounds. 1466 * 1467 * 'pnum' is set to the number of bytes (including and immediately following 1468 * the specified offset) that are known to be in the same 1469 * allocated/unallocated state. 1470 * 1471 * 'bytes' is the max value 'pnum' should be set to. 1472 * 1473 * (Based on raw_co_block_status() from file-posix.c.) 1474 */ 1475 static int coroutine_fn qemu_gluster_co_block_status(BlockDriverState *bs, 1476 bool want_zero, 1477 int64_t offset, 1478 int64_t bytes, 1479 int64_t *pnum, 1480 int64_t *map, 1481 BlockDriverState **file) 1482 { 1483 BDRVGlusterState *s = bs->opaque; 1484 off_t data = 0, hole = 0; 1485 int ret = -EINVAL; 1486 1487 if (!s->fd) { 1488 return ret; 1489 } 1490 1491 if (!want_zero) { 1492 *pnum = bytes; 1493 *map = offset; 1494 *file = bs; 1495 return BDRV_BLOCK_DATA | BDRV_BLOCK_OFFSET_VALID; 1496 } 1497 1498 ret = find_allocation(bs, offset, &data, &hole); 1499 if (ret == -ENXIO) { 1500 /* Trailing hole */ 1501 *pnum = bytes; 1502 ret = BDRV_BLOCK_ZERO; 1503 } else if (ret < 0) { 1504 /* No info available, so pretend there are no holes */ 1505 *pnum = bytes; 1506 ret = BDRV_BLOCK_DATA; 1507 } else if (data == offset) { 1508 /* On a data extent, compute bytes to the end of the extent, 1509 * possibly including a partial sector at EOF. */ 1510 *pnum = MIN(bytes, hole - offset); 1511 ret = BDRV_BLOCK_DATA; 1512 } else { 1513 /* On a hole, compute bytes to the beginning of the next extent. */ 1514 assert(hole == offset); 1515 *pnum = MIN(bytes, data - offset); 1516 ret = BDRV_BLOCK_ZERO; 1517 } 1518 1519 *map = offset; 1520 *file = bs; 1521 1522 return ret | BDRV_BLOCK_OFFSET_VALID; 1523 } 1524 1525 1526 static const char *const gluster_strong_open_opts[] = { 1527 GLUSTER_OPT_VOLUME, 1528 GLUSTER_OPT_PATH, 1529 GLUSTER_OPT_TYPE, 1530 GLUSTER_OPT_SERVER_PATTERN, 1531 GLUSTER_OPT_HOST, 1532 GLUSTER_OPT_PORT, 1533 GLUSTER_OPT_TO, 1534 GLUSTER_OPT_IPV4, 1535 GLUSTER_OPT_IPV6, 1536 GLUSTER_OPT_SOCKET, 1537 1538 NULL 1539 }; 1540 1541 static BlockDriver bdrv_gluster = { 1542 .format_name = "gluster", 1543 .protocol_name = "gluster", 1544 .instance_size = sizeof(BDRVGlusterState), 1545 .bdrv_needs_filename = false, 1546 .bdrv_file_open = qemu_gluster_open, 1547 .bdrv_reopen_prepare = qemu_gluster_reopen_prepare, 1548 .bdrv_reopen_commit = qemu_gluster_reopen_commit, 1549 .bdrv_reopen_abort = qemu_gluster_reopen_abort, 1550 .bdrv_close = qemu_gluster_close, 1551 .bdrv_co_create = qemu_gluster_co_create, 1552 .bdrv_co_create_opts = qemu_gluster_co_create_opts, 1553 .bdrv_getlength = qemu_gluster_getlength, 1554 .bdrv_get_allocated_file_size = qemu_gluster_allocated_file_size, 1555 .bdrv_co_truncate = qemu_gluster_co_truncate, 1556 .bdrv_co_readv = qemu_gluster_co_readv, 1557 .bdrv_co_writev = qemu_gluster_co_writev, 1558 .bdrv_co_flush_to_disk = qemu_gluster_co_flush_to_disk, 1559 #ifdef CONFIG_GLUSTERFS_DISCARD 1560 .bdrv_co_pdiscard = qemu_gluster_co_pdiscard, 1561 #endif 1562 #ifdef CONFIG_GLUSTERFS_ZEROFILL 1563 .bdrv_co_pwrite_zeroes = qemu_gluster_co_pwrite_zeroes, 1564 #endif 1565 .bdrv_co_block_status = qemu_gluster_co_block_status, 1566 .bdrv_refresh_limits = qemu_gluster_refresh_limits, 1567 .create_opts = &qemu_gluster_create_opts, 1568 .strong_runtime_opts = gluster_strong_open_opts, 1569 }; 1570 1571 static BlockDriver bdrv_gluster_tcp = { 1572 .format_name = "gluster", 1573 .protocol_name = "gluster+tcp", 1574 .instance_size = sizeof(BDRVGlusterState), 1575 .bdrv_needs_filename = false, 1576 .bdrv_file_open = qemu_gluster_open, 1577 .bdrv_reopen_prepare = qemu_gluster_reopen_prepare, 1578 .bdrv_reopen_commit = qemu_gluster_reopen_commit, 1579 .bdrv_reopen_abort = qemu_gluster_reopen_abort, 1580 .bdrv_close = qemu_gluster_close, 1581 .bdrv_co_create = qemu_gluster_co_create, 1582 .bdrv_co_create_opts = qemu_gluster_co_create_opts, 1583 .bdrv_getlength = qemu_gluster_getlength, 1584 .bdrv_get_allocated_file_size = qemu_gluster_allocated_file_size, 1585 .bdrv_co_truncate = qemu_gluster_co_truncate, 1586 .bdrv_co_readv = qemu_gluster_co_readv, 1587 .bdrv_co_writev = qemu_gluster_co_writev, 1588 .bdrv_co_flush_to_disk = qemu_gluster_co_flush_to_disk, 1589 #ifdef CONFIG_GLUSTERFS_DISCARD 1590 .bdrv_co_pdiscard = qemu_gluster_co_pdiscard, 1591 #endif 1592 #ifdef CONFIG_GLUSTERFS_ZEROFILL 1593 .bdrv_co_pwrite_zeroes = qemu_gluster_co_pwrite_zeroes, 1594 #endif 1595 .bdrv_co_block_status = qemu_gluster_co_block_status, 1596 .bdrv_refresh_limits = qemu_gluster_refresh_limits, 1597 .create_opts = &qemu_gluster_create_opts, 1598 .strong_runtime_opts = gluster_strong_open_opts, 1599 }; 1600 1601 static BlockDriver bdrv_gluster_unix = { 1602 .format_name = "gluster", 1603 .protocol_name = "gluster+unix", 1604 .instance_size = sizeof(BDRVGlusterState), 1605 .bdrv_needs_filename = true, 1606 .bdrv_file_open = qemu_gluster_open, 1607 .bdrv_reopen_prepare = qemu_gluster_reopen_prepare, 1608 .bdrv_reopen_commit = qemu_gluster_reopen_commit, 1609 .bdrv_reopen_abort = qemu_gluster_reopen_abort, 1610 .bdrv_close = qemu_gluster_close, 1611 .bdrv_co_create = qemu_gluster_co_create, 1612 .bdrv_co_create_opts = qemu_gluster_co_create_opts, 1613 .bdrv_getlength = qemu_gluster_getlength, 1614 .bdrv_get_allocated_file_size = qemu_gluster_allocated_file_size, 1615 .bdrv_co_truncate = qemu_gluster_co_truncate, 1616 .bdrv_co_readv = qemu_gluster_co_readv, 1617 .bdrv_co_writev = qemu_gluster_co_writev, 1618 .bdrv_co_flush_to_disk = qemu_gluster_co_flush_to_disk, 1619 #ifdef CONFIG_GLUSTERFS_DISCARD 1620 .bdrv_co_pdiscard = qemu_gluster_co_pdiscard, 1621 #endif 1622 #ifdef CONFIG_GLUSTERFS_ZEROFILL 1623 .bdrv_co_pwrite_zeroes = qemu_gluster_co_pwrite_zeroes, 1624 #endif 1625 .bdrv_co_block_status = qemu_gluster_co_block_status, 1626 .bdrv_refresh_limits = qemu_gluster_refresh_limits, 1627 .create_opts = &qemu_gluster_create_opts, 1628 .strong_runtime_opts = gluster_strong_open_opts, 1629 }; 1630 1631 /* rdma is deprecated (actually never supported for volfile fetch). 1632 * Let's maintain it for the protocol compatibility, to make sure things 1633 * won't break immediately. For now, gluster+rdma will fall back to gluster+tcp 1634 * protocol with a warning. 1635 * TODO: remove gluster+rdma interface support 1636 */ 1637 static BlockDriver bdrv_gluster_rdma = { 1638 .format_name = "gluster", 1639 .protocol_name = "gluster+rdma", 1640 .instance_size = sizeof(BDRVGlusterState), 1641 .bdrv_needs_filename = true, 1642 .bdrv_file_open = qemu_gluster_open, 1643 .bdrv_reopen_prepare = qemu_gluster_reopen_prepare, 1644 .bdrv_reopen_commit = qemu_gluster_reopen_commit, 1645 .bdrv_reopen_abort = qemu_gluster_reopen_abort, 1646 .bdrv_close = qemu_gluster_close, 1647 .bdrv_co_create = qemu_gluster_co_create, 1648 .bdrv_co_create_opts = qemu_gluster_co_create_opts, 1649 .bdrv_getlength = qemu_gluster_getlength, 1650 .bdrv_get_allocated_file_size = qemu_gluster_allocated_file_size, 1651 .bdrv_co_truncate = qemu_gluster_co_truncate, 1652 .bdrv_co_readv = qemu_gluster_co_readv, 1653 .bdrv_co_writev = qemu_gluster_co_writev, 1654 .bdrv_co_flush_to_disk = qemu_gluster_co_flush_to_disk, 1655 #ifdef CONFIG_GLUSTERFS_DISCARD 1656 .bdrv_co_pdiscard = qemu_gluster_co_pdiscard, 1657 #endif 1658 #ifdef CONFIG_GLUSTERFS_ZEROFILL 1659 .bdrv_co_pwrite_zeroes = qemu_gluster_co_pwrite_zeroes, 1660 #endif 1661 .bdrv_co_block_status = qemu_gluster_co_block_status, 1662 .bdrv_refresh_limits = qemu_gluster_refresh_limits, 1663 .create_opts = &qemu_gluster_create_opts, 1664 .strong_runtime_opts = gluster_strong_open_opts, 1665 }; 1666 1667 static void bdrv_gluster_init(void) 1668 { 1669 bdrv_register(&bdrv_gluster_rdma); 1670 bdrv_register(&bdrv_gluster_unix); 1671 bdrv_register(&bdrv_gluster_tcp); 1672 bdrv_register(&bdrv_gluster); 1673 } 1674 1675 block_init(bdrv_gluster_init); 1676