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