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