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-io.h" 15 #include "block/block_int.h" 16 #include "block/qdict.h" 17 #include "qapi/error.h" 18 #include "qapi/qmp/qdict.h" 19 #include "qapi/qmp/qerror.h" 20 #include "qemu/error-report.h" 21 #include "qemu/module.h" 22 #include "qemu/option.h" 23 #include "qemu/cutils.h" 24 25 #ifdef CONFIG_GLUSTERFS_FTRUNCATE_HAS_STAT 26 # define glfs_ftruncate(fd, offset) glfs_ftruncate(fd, offset, NULL, NULL) 27 #endif 28 29 #define GLUSTER_OPT_FILENAME "filename" 30 #define GLUSTER_OPT_VOLUME "volume" 31 #define GLUSTER_OPT_PATH "path" 32 #define GLUSTER_OPT_TYPE "type" 33 #define GLUSTER_OPT_SERVER_PATTERN "server." 34 #define GLUSTER_OPT_HOST "host" 35 #define GLUSTER_OPT_PORT "port" 36 #define GLUSTER_OPT_TO "to" 37 #define GLUSTER_OPT_IPV4 "ipv4" 38 #define GLUSTER_OPT_IPV6 "ipv6" 39 #define GLUSTER_OPT_SOCKET "socket" 40 #define GLUSTER_OPT_DEBUG "debug" 41 #define GLUSTER_DEFAULT_PORT 24007 42 #define GLUSTER_DEBUG_DEFAULT 4 43 #define GLUSTER_DEBUG_MAX 9 44 #define GLUSTER_OPT_LOGFILE "logfile" 45 #define GLUSTER_LOGFILE_DEFAULT "-" /* handled in libgfapi as /dev/stderr */ 46 /* 47 * Several versions of GlusterFS (3.12? -> 6.0.1) fail when the transfer size 48 * is greater or equal to 1024 MiB, so we are limiting the transfer size to 512 49 * MiB to avoid this rare issue. 50 */ 51 #define GLUSTER_MAX_TRANSFER (512 * MiB) 52 53 #define GERR_INDEX_HINT "hint: check in 'server' array index '%d'\n" 54 55 typedef struct GlusterAIOCB { 56 int64_t size; 57 int ret; 58 Coroutine *coroutine; 59 AioContext *aio_context; 60 } GlusterAIOCB; 61 62 typedef struct BDRVGlusterState { 63 struct glfs *glfs; 64 struct glfs_fd *fd; 65 char *logfile; 66 bool supports_seek_data; 67 int debug; 68 } BDRVGlusterState; 69 70 typedef struct BDRVGlusterReopenState { 71 struct glfs *glfs; 72 struct glfs_fd *fd; 73 } BDRVGlusterReopenState; 74 75 76 typedef struct GlfsPreopened { 77 char *volume; 78 glfs_t *fs; 79 int ref; 80 } GlfsPreopened; 81 82 typedef struct ListElement { 83 QLIST_ENTRY(ListElement) list; 84 GlfsPreopened saved; 85 } ListElement; 86 87 static QLIST_HEAD(, ListElement) glfs_list; 88 89 static QemuOptsList qemu_gluster_create_opts = { 90 .name = "qemu-gluster-create-opts", 91 .head = QTAILQ_HEAD_INITIALIZER(qemu_gluster_create_opts.head), 92 .desc = { 93 { 94 .name = BLOCK_OPT_SIZE, 95 .type = QEMU_OPT_SIZE, 96 .help = "Virtual disk size" 97 }, 98 { 99 .name = BLOCK_OPT_PREALLOC, 100 .type = QEMU_OPT_STRING, 101 .help = "Preallocation mode (allowed values: off" 102 #ifdef CONFIG_GLUSTERFS_FALLOCATE 103 ", falloc" 104 #endif 105 #ifdef CONFIG_GLUSTERFS_ZEROFILL 106 ", full" 107 #endif 108 ")" 109 }, 110 { 111 .name = GLUSTER_OPT_DEBUG, 112 .type = QEMU_OPT_NUMBER, 113 .help = "Gluster log level, valid range is 0-9", 114 }, 115 { 116 .name = GLUSTER_OPT_LOGFILE, 117 .type = QEMU_OPT_STRING, 118 .help = "Logfile path of libgfapi", 119 }, 120 { /* end of list */ } 121 } 122 }; 123 124 static QemuOptsList runtime_opts = { 125 .name = "gluster", 126 .head = QTAILQ_HEAD_INITIALIZER(runtime_opts.head), 127 .desc = { 128 { 129 .name = GLUSTER_OPT_FILENAME, 130 .type = QEMU_OPT_STRING, 131 .help = "URL to the gluster image", 132 }, 133 { 134 .name = GLUSTER_OPT_DEBUG, 135 .type = QEMU_OPT_NUMBER, 136 .help = "Gluster log level, valid range is 0-9", 137 }, 138 { 139 .name = GLUSTER_OPT_LOGFILE, 140 .type = QEMU_OPT_STRING, 141 .help = "Logfile path of libgfapi", 142 }, 143 { /* end of list */ } 144 }, 145 }; 146 147 static QemuOptsList runtime_json_opts = { 148 .name = "gluster_json", 149 .head = QTAILQ_HEAD_INITIALIZER(runtime_json_opts.head), 150 .desc = { 151 { 152 .name = GLUSTER_OPT_VOLUME, 153 .type = QEMU_OPT_STRING, 154 .help = "name of gluster volume where VM image resides", 155 }, 156 { 157 .name = GLUSTER_OPT_PATH, 158 .type = QEMU_OPT_STRING, 159 .help = "absolute path to image file in gluster volume", 160 }, 161 { 162 .name = GLUSTER_OPT_DEBUG, 163 .type = QEMU_OPT_NUMBER, 164 .help = "Gluster log level, valid range is 0-9", 165 }, 166 { /* end of list */ } 167 }, 168 }; 169 170 static QemuOptsList runtime_type_opts = { 171 .name = "gluster_type", 172 .head = QTAILQ_HEAD_INITIALIZER(runtime_type_opts.head), 173 .desc = { 174 { 175 .name = GLUSTER_OPT_TYPE, 176 .type = QEMU_OPT_STRING, 177 .help = "inet|unix", 178 }, 179 { /* end of list */ } 180 }, 181 }; 182 183 static QemuOptsList runtime_unix_opts = { 184 .name = "gluster_unix", 185 .head = QTAILQ_HEAD_INITIALIZER(runtime_unix_opts.head), 186 .desc = { 187 { 188 .name = GLUSTER_OPT_SOCKET, 189 .type = QEMU_OPT_STRING, 190 .help = "socket file path (legacy)", 191 }, 192 { 193 .name = GLUSTER_OPT_PATH, 194 .type = QEMU_OPT_STRING, 195 .help = "socket file path (QAPI)", 196 }, 197 { /* end of list */ } 198 }, 199 }; 200 201 static QemuOptsList runtime_inet_opts = { 202 .name = "gluster_inet", 203 .head = QTAILQ_HEAD_INITIALIZER(runtime_inet_opts.head), 204 .desc = { 205 { 206 .name = GLUSTER_OPT_TYPE, 207 .type = QEMU_OPT_STRING, 208 .help = "inet|unix", 209 }, 210 { 211 .name = GLUSTER_OPT_HOST, 212 .type = QEMU_OPT_STRING, 213 .help = "host address (hostname/ipv4/ipv6 addresses)", 214 }, 215 { 216 .name = GLUSTER_OPT_PORT, 217 .type = QEMU_OPT_STRING, 218 .help = "port number on which glusterd is listening (default 24007)", 219 }, 220 { 221 .name = "to", 222 .type = QEMU_OPT_NUMBER, 223 .help = "max port number, not supported by gluster", 224 }, 225 { 226 .name = "ipv4", 227 .type = QEMU_OPT_BOOL, 228 .help = "ipv4 bool value, not supported by gluster", 229 }, 230 { 231 .name = "ipv6", 232 .type = QEMU_OPT_BOOL, 233 .help = "ipv6 bool value, not supported by gluster", 234 }, 235 { /* end of list */ } 236 }, 237 }; 238 239 static void glfs_set_preopened(const char *volume, glfs_t *fs) 240 { 241 ListElement *entry = NULL; 242 243 entry = g_new(ListElement, 1); 244 245 entry->saved.volume = g_strdup(volume); 246 247 entry->saved.fs = fs; 248 entry->saved.ref = 1; 249 250 QLIST_INSERT_HEAD(&glfs_list, entry, list); 251 } 252 253 static glfs_t *glfs_find_preopened(const char *volume) 254 { 255 ListElement *entry = NULL; 256 257 QLIST_FOREACH(entry, &glfs_list, list) { 258 if (strcmp(entry->saved.volume, volume) == 0) { 259 entry->saved.ref++; 260 return entry->saved.fs; 261 } 262 } 263 264 return NULL; 265 } 266 267 static void glfs_clear_preopened(glfs_t *fs) 268 { 269 ListElement *entry = NULL; 270 ListElement *next; 271 272 if (fs == NULL) { 273 return; 274 } 275 276 QLIST_FOREACH_SAFE(entry, &glfs_list, list, next) { 277 if (entry->saved.fs == fs) { 278 if (--entry->saved.ref) { 279 return; 280 } 281 282 QLIST_REMOVE(entry, list); 283 284 glfs_fini(entry->saved.fs); 285 g_free(entry->saved.volume); 286 g_free(entry); 287 } 288 } 289 } 290 291 static int parse_volume_options(BlockdevOptionsGluster *gconf, const char *path) 292 { 293 const char *p, *q; 294 295 if (!path) { 296 return -EINVAL; 297 } 298 299 /* volume */ 300 p = q = path + strspn(path, "/"); 301 p += strcspn(p, "/"); 302 if (*p == '\0') { 303 return -EINVAL; 304 } 305 gconf->volume = g_strndup(q, p - q); 306 307 /* path */ 308 p += strspn(p, "/"); 309 if (*p == '\0') { 310 return -EINVAL; 311 } 312 gconf->path = g_strdup(p); 313 return 0; 314 } 315 316 /* 317 * file=gluster[+transport]://[host[:port]]/volume/path[?socket=...] 318 * 319 * 'gluster' is the protocol. 320 * 321 * 'transport' specifies the transport type used to connect to gluster 322 * management daemon (glusterd). Valid transport types are 323 * tcp or unix. If a transport type isn't specified, then tcp type is assumed. 324 * 325 * 'host' specifies the host where the volume file specification for 326 * the given volume resides. This can be either hostname or ipv4 address. 327 * If transport type is 'unix', then 'host' field should not be specified. 328 * The 'socket' field needs to be populated with the path to unix domain 329 * socket. 330 * 331 * 'port' is the port number on which glusterd is listening. This is optional 332 * and if not specified, QEMU will send 0 which will make gluster to use the 333 * default port. If the transport type is unix, then 'port' should not be 334 * specified. 335 * 336 * 'volume' is the name of the gluster volume which contains the VM image. 337 * 338 * 'path' is the path to the actual VM image that resides on gluster volume. 339 * 340 * Examples: 341 * 342 * file=gluster://1.2.3.4/testvol/a.img 343 * file=gluster+tcp://1.2.3.4/testvol/a.img 344 * file=gluster+tcp://1.2.3.4:24007/testvol/dir/a.img 345 * file=gluster+tcp://host.domain.com:24007/testvol/dir/a.img 346 * file=gluster+unix:///testvol/dir/a.img?socket=/tmp/glusterd.socket 347 */ 348 static int qemu_gluster_parse_uri(BlockdevOptionsGluster *gconf, 349 const char *filename) 350 { 351 g_autoptr(GUri) uri = g_uri_parse(filename, G_URI_FLAGS_NONE, NULL); 352 g_autoptr(GHashTable) qp = NULL; 353 SocketAddress *gsconf; 354 bool is_unix = false; 355 const char *uri_scheme, *uri_query, *uri_server; 356 int uri_port, ret; 357 358 if (!uri) { 359 return -EINVAL; 360 } 361 362 gsconf = g_new0(SocketAddress, 1); 363 QAPI_LIST_PREPEND(gconf->server, gsconf); 364 365 /* transport */ 366 uri_scheme = g_uri_get_scheme(uri); 367 if (!uri_scheme || !strcmp(uri_scheme, "gluster")) { 368 gsconf->type = SOCKET_ADDRESS_TYPE_INET; 369 } else if (!strcmp(uri_scheme, "gluster+tcp")) { 370 gsconf->type = SOCKET_ADDRESS_TYPE_INET; 371 } else if (!strcmp(uri_scheme, "gluster+unix")) { 372 gsconf->type = SOCKET_ADDRESS_TYPE_UNIX; 373 is_unix = true; 374 } else { 375 return -EINVAL; 376 } 377 378 ret = parse_volume_options(gconf, g_uri_get_path(uri)); 379 if (ret < 0) { 380 return ret; 381 } 382 383 uri_query = g_uri_get_query(uri); 384 if (uri_query) { 385 qp = g_uri_parse_params(uri_query, -1, "&", G_URI_PARAMS_NONE, NULL); 386 if (!qp) { 387 return -EINVAL; 388 } 389 ret = g_hash_table_size(qp); 390 if (ret > 1 || (is_unix && !ret) || (!is_unix && ret)) { 391 return -EINVAL; 392 } 393 } 394 395 uri_server = g_uri_get_host(uri); 396 uri_port = g_uri_get_port(uri); 397 398 if (is_unix) { 399 char *uri_socket = g_hash_table_lookup(qp, "socket"); 400 if (uri_server || uri_port != -1 || !uri_socket) { 401 return -EINVAL; 402 } 403 gsconf->u.q_unix.path = g_strdup(uri_socket); 404 } else { 405 gsconf->u.inet.host = g_strdup(uri_server ? uri_server : "localhost"); 406 if (uri_port > 0) { 407 gsconf->u.inet.port = g_strdup_printf("%d", uri_port); 408 } else { 409 gsconf->u.inet.port = g_strdup_printf("%d", GLUSTER_DEFAULT_PORT); 410 } 411 } 412 413 return 0; 414 } 415 416 static struct glfs *qemu_gluster_glfs_init(BlockdevOptionsGluster *gconf, 417 Error **errp) 418 { 419 struct glfs *glfs; 420 int ret; 421 int old_errno; 422 SocketAddressList *server; 423 uint64_t port; 424 425 glfs = glfs_find_preopened(gconf->volume); 426 if (glfs) { 427 return glfs; 428 } 429 430 glfs = glfs_new(gconf->volume); 431 if (!glfs) { 432 goto out; 433 } 434 435 glfs_set_preopened(gconf->volume, glfs); 436 437 for (server = gconf->server; server; server = server->next) { 438 switch (server->value->type) { 439 case SOCKET_ADDRESS_TYPE_UNIX: 440 ret = glfs_set_volfile_server(glfs, "unix", 441 server->value->u.q_unix.path, 0); 442 break; 443 case SOCKET_ADDRESS_TYPE_INET: 444 if (parse_uint_full(server->value->u.inet.port, 10, &port) < 0 || 445 port > 65535) { 446 error_setg(errp, "'%s' is not a valid port number", 447 server->value->u.inet.port); 448 errno = EINVAL; 449 goto out; 450 } 451 ret = glfs_set_volfile_server(glfs, "tcp", 452 server->value->u.inet.host, 453 (int)port); 454 break; 455 case SOCKET_ADDRESS_TYPE_VSOCK: 456 case SOCKET_ADDRESS_TYPE_FD: 457 default: 458 abort(); 459 } 460 461 if (ret < 0) { 462 goto out; 463 } 464 } 465 466 ret = glfs_set_logging(glfs, gconf->logfile, gconf->debug); 467 if (ret < 0) { 468 goto out; 469 } 470 471 ret = glfs_init(glfs); 472 if (ret) { 473 error_setg(errp, "Gluster connection for volume %s, path %s failed" 474 " to connect", gconf->volume, gconf->path); 475 for (server = gconf->server; server; server = server->next) { 476 if (server->value->type == SOCKET_ADDRESS_TYPE_UNIX) { 477 error_append_hint(errp, "hint: failed on socket %s ", 478 server->value->u.q_unix.path); 479 } else { 480 error_append_hint(errp, "hint: failed on host %s and port %s ", 481 server->value->u.inet.host, 482 server->value->u.inet.port); 483 } 484 } 485 486 error_append_hint(errp, "Please refer to gluster logs for more info\n"); 487 488 /* glfs_init sometimes doesn't set errno although docs suggest that */ 489 if (errno == 0) { 490 errno = EINVAL; 491 } 492 493 goto out; 494 } 495 return glfs; 496 497 out: 498 if (glfs) { 499 old_errno = errno; 500 glfs_clear_preopened(glfs); 501 errno = old_errno; 502 } 503 return NULL; 504 } 505 506 /* 507 * Convert the json formatted command line into qapi. 508 */ 509 static int qemu_gluster_parse_json(BlockdevOptionsGluster *gconf, 510 QDict *options, Error **errp) 511 { 512 QemuOpts *opts; 513 SocketAddress *gsconf = NULL; 514 SocketAddressList **tail; 515 QDict *backing_options = NULL; 516 Error *local_err = NULL; 517 char *str = NULL; 518 const char *ptr; 519 int i, type, num_servers; 520 521 /* create opts info from runtime_json_opts list */ 522 opts = qemu_opts_create(&runtime_json_opts, NULL, 0, &error_abort); 523 if (!qemu_opts_absorb_qdict(opts, options, errp)) { 524 goto out; 525 } 526 527 num_servers = qdict_array_entries(options, GLUSTER_OPT_SERVER_PATTERN); 528 if (num_servers < 1) { 529 error_setg(&local_err, QERR_MISSING_PARAMETER, "server"); 530 goto out; 531 } 532 533 ptr = qemu_opt_get(opts, GLUSTER_OPT_VOLUME); 534 if (!ptr) { 535 error_setg(&local_err, QERR_MISSING_PARAMETER, GLUSTER_OPT_VOLUME); 536 goto out; 537 } 538 gconf->volume = g_strdup(ptr); 539 540 ptr = qemu_opt_get(opts, GLUSTER_OPT_PATH); 541 if (!ptr) { 542 error_setg(&local_err, QERR_MISSING_PARAMETER, GLUSTER_OPT_PATH); 543 goto out; 544 } 545 gconf->path = g_strdup(ptr); 546 qemu_opts_del(opts); 547 tail = &gconf->server; 548 549 for (i = 0; i < num_servers; i++) { 550 str = g_strdup_printf(GLUSTER_OPT_SERVER_PATTERN"%d.", i); 551 qdict_extract_subqdict(options, &backing_options, str); 552 553 /* create opts info from runtime_type_opts list */ 554 opts = qemu_opts_create(&runtime_type_opts, NULL, 0, &error_abort); 555 if (!qemu_opts_absorb_qdict(opts, backing_options, errp)) { 556 goto out; 557 } 558 559 ptr = qemu_opt_get(opts, GLUSTER_OPT_TYPE); 560 if (!ptr) { 561 error_setg(&local_err, QERR_MISSING_PARAMETER, GLUSTER_OPT_TYPE); 562 error_append_hint(&local_err, GERR_INDEX_HINT, i); 563 goto out; 564 565 } 566 gsconf = g_new0(SocketAddress, 1); 567 if (!strcmp(ptr, "tcp")) { 568 ptr = "inet"; /* accept legacy "tcp" */ 569 } 570 type = qapi_enum_parse(&SocketAddressType_lookup, ptr, -1, NULL); 571 if (type != SOCKET_ADDRESS_TYPE_INET 572 && type != SOCKET_ADDRESS_TYPE_UNIX) { 573 error_setg(&local_err, 574 "Parameter '%s' may be 'inet' or 'unix'", 575 GLUSTER_OPT_TYPE); 576 error_append_hint(&local_err, GERR_INDEX_HINT, i); 577 goto out; 578 } 579 gsconf->type = type; 580 qemu_opts_del(opts); 581 582 if (gsconf->type == SOCKET_ADDRESS_TYPE_INET) { 583 /* create opts info from runtime_inet_opts list */ 584 opts = qemu_opts_create(&runtime_inet_opts, NULL, 0, &error_abort); 585 if (!qemu_opts_absorb_qdict(opts, backing_options, errp)) { 586 goto out; 587 } 588 589 ptr = qemu_opt_get(opts, GLUSTER_OPT_HOST); 590 if (!ptr) { 591 error_setg(&local_err, QERR_MISSING_PARAMETER, 592 GLUSTER_OPT_HOST); 593 error_append_hint(&local_err, GERR_INDEX_HINT, i); 594 goto out; 595 } 596 gsconf->u.inet.host = g_strdup(ptr); 597 ptr = qemu_opt_get(opts, GLUSTER_OPT_PORT); 598 if (!ptr) { 599 error_setg(&local_err, QERR_MISSING_PARAMETER, 600 GLUSTER_OPT_PORT); 601 error_append_hint(&local_err, GERR_INDEX_HINT, i); 602 goto out; 603 } 604 gsconf->u.inet.port = g_strdup(ptr); 605 606 /* defend for unsupported fields in InetSocketAddress, 607 * i.e. @ipv4, @ipv6 and @to 608 */ 609 ptr = qemu_opt_get(opts, GLUSTER_OPT_TO); 610 if (ptr) { 611 gsconf->u.inet.has_to = true; 612 } 613 ptr = qemu_opt_get(opts, GLUSTER_OPT_IPV4); 614 if (ptr) { 615 gsconf->u.inet.has_ipv4 = true; 616 } 617 ptr = qemu_opt_get(opts, GLUSTER_OPT_IPV6); 618 if (ptr) { 619 gsconf->u.inet.has_ipv6 = true; 620 } 621 if (gsconf->u.inet.has_to) { 622 error_setg(&local_err, "Parameter 'to' not supported"); 623 goto out; 624 } 625 if (gsconf->u.inet.has_ipv4 || gsconf->u.inet.has_ipv6) { 626 error_setg(&local_err, "Parameters 'ipv4/ipv6' not supported"); 627 goto out; 628 } 629 qemu_opts_del(opts); 630 } else { 631 /* create opts info from runtime_unix_opts list */ 632 opts = qemu_opts_create(&runtime_unix_opts, NULL, 0, &error_abort); 633 if (!qemu_opts_absorb_qdict(opts, backing_options, errp)) { 634 goto out; 635 } 636 637 ptr = qemu_opt_get(opts, GLUSTER_OPT_PATH); 638 if (!ptr) { 639 ptr = qemu_opt_get(opts, GLUSTER_OPT_SOCKET); 640 } else if (qemu_opt_get(opts, GLUSTER_OPT_SOCKET)) { 641 error_setg(&local_err, 642 "Conflicting parameters 'path' and 'socket'"); 643 error_append_hint(&local_err, GERR_INDEX_HINT, i); 644 goto out; 645 } 646 if (!ptr) { 647 error_setg(&local_err, QERR_MISSING_PARAMETER, 648 GLUSTER_OPT_PATH); 649 error_append_hint(&local_err, GERR_INDEX_HINT, i); 650 goto out; 651 } 652 gsconf->u.q_unix.path = g_strdup(ptr); 653 qemu_opts_del(opts); 654 } 655 656 QAPI_LIST_APPEND(tail, gsconf); 657 gsconf = NULL; 658 659 qobject_unref(backing_options); 660 backing_options = NULL; 661 g_free(str); 662 str = NULL; 663 } 664 665 return 0; 666 667 out: 668 error_propagate(errp, local_err); 669 qapi_free_SocketAddress(gsconf); 670 qemu_opts_del(opts); 671 g_free(str); 672 qobject_unref(backing_options); 673 errno = EINVAL; 674 return -errno; 675 } 676 677 /* Converts options given in @filename and the @options QDict into the QAPI 678 * object @gconf. */ 679 static int qemu_gluster_parse(BlockdevOptionsGluster *gconf, 680 const char *filename, 681 QDict *options, Error **errp) 682 { 683 int ret; 684 if (filename) { 685 ret = qemu_gluster_parse_uri(gconf, filename); 686 if (ret < 0) { 687 error_setg(errp, "invalid URI %s", filename); 688 error_append_hint(errp, "Usage: file=gluster[+transport]://" 689 "[host[:port]]volume/path[?socket=...]" 690 "[,file.debug=N]" 691 "[,file.logfile=/path/filename.log]\n"); 692 return ret; 693 } 694 } else { 695 ret = qemu_gluster_parse_json(gconf, options, errp); 696 if (ret < 0) { 697 error_append_hint(errp, "Usage: " 698 "-drive driver=qcow2,file.driver=gluster," 699 "file.volume=testvol,file.path=/path/a.qcow2" 700 "[,file.debug=9]" 701 "[,file.logfile=/path/filename.log]," 702 "file.server.0.type=inet," 703 "file.server.0.host=1.2.3.4," 704 "file.server.0.port=24007," 705 "file.server.1.transport=unix," 706 "file.server.1.path=/var/run/glusterd.socket ..." 707 "\n"); 708 return ret; 709 } 710 } 711 712 return 0; 713 } 714 715 static struct glfs *qemu_gluster_init(BlockdevOptionsGluster *gconf, 716 const char *filename, 717 QDict *options, Error **errp) 718 { 719 int ret; 720 721 ret = qemu_gluster_parse(gconf, filename, options, errp); 722 if (ret < 0) { 723 errno = -ret; 724 return NULL; 725 } 726 727 return qemu_gluster_glfs_init(gconf, errp); 728 } 729 730 /* 731 * AIO callback routine called from GlusterFS thread. 732 */ 733 static void gluster_finish_aiocb(struct glfs_fd *fd, ssize_t ret, 734 #ifdef CONFIG_GLUSTERFS_IOCB_HAS_STAT 735 struct glfs_stat *pre, struct glfs_stat *post, 736 #endif 737 void *arg) 738 { 739 GlusterAIOCB *acb = (GlusterAIOCB *)arg; 740 741 if (!ret || ret == acb->size) { 742 acb->ret = 0; /* Success */ 743 } else if (ret < 0) { 744 acb->ret = -errno; /* Read/Write failed */ 745 } else { 746 acb->ret = -EIO; /* Partial read/write - fail it */ 747 } 748 749 aio_co_schedule(acb->aio_context, acb->coroutine); 750 } 751 752 static void qemu_gluster_parse_flags(int bdrv_flags, int *open_flags) 753 { 754 assert(open_flags != NULL); 755 756 *open_flags |= O_BINARY; 757 758 if (bdrv_flags & BDRV_O_RDWR) { 759 *open_flags |= O_RDWR; 760 } else { 761 *open_flags |= O_RDONLY; 762 } 763 764 if ((bdrv_flags & BDRV_O_NOCACHE)) { 765 *open_flags |= O_DIRECT; 766 } 767 } 768 769 /* 770 * Do SEEK_DATA/HOLE to detect if it is functional. Older broken versions of 771 * gfapi incorrectly return the current offset when SEEK_DATA/HOLE is used. 772 * - Corrected versions return -1 and set errno to EINVAL. 773 * - Versions that support SEEK_DATA/HOLE correctly, will return -1 and set 774 * errno to ENXIO when SEEK_DATA is called with a position of EOF. 775 */ 776 static bool qemu_gluster_test_seek(struct glfs_fd *fd) 777 { 778 off_t ret = 0; 779 780 #if defined SEEK_HOLE && defined SEEK_DATA 781 off_t eof; 782 783 eof = glfs_lseek(fd, 0, SEEK_END); 784 if (eof < 0) { 785 /* this should never occur */ 786 return false; 787 } 788 789 /* this should always fail with ENXIO if SEEK_DATA is supported */ 790 ret = glfs_lseek(fd, eof, SEEK_DATA); 791 #endif 792 793 return (ret < 0) && (errno == ENXIO); 794 } 795 796 static int qemu_gluster_open(BlockDriverState *bs, QDict *options, 797 int bdrv_flags, Error **errp) 798 { 799 BDRVGlusterState *s = bs->opaque; 800 int open_flags = 0; 801 int ret = 0; 802 BlockdevOptionsGluster *gconf = NULL; 803 QemuOpts *opts; 804 const char *filename, *logfile; 805 806 opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort); 807 if (!qemu_opts_absorb_qdict(opts, options, errp)) { 808 ret = -EINVAL; 809 goto out; 810 } 811 812 filename = qemu_opt_get(opts, GLUSTER_OPT_FILENAME); 813 814 s->debug = qemu_opt_get_number(opts, GLUSTER_OPT_DEBUG, 815 GLUSTER_DEBUG_DEFAULT); 816 if (s->debug < 0) { 817 s->debug = 0; 818 } else if (s->debug > GLUSTER_DEBUG_MAX) { 819 s->debug = GLUSTER_DEBUG_MAX; 820 } 821 822 gconf = g_new0(BlockdevOptionsGluster, 1); 823 gconf->debug = s->debug; 824 gconf->has_debug = true; 825 826 logfile = qemu_opt_get(opts, GLUSTER_OPT_LOGFILE); 827 s->logfile = g_strdup(logfile ? logfile : GLUSTER_LOGFILE_DEFAULT); 828 829 gconf->logfile = g_strdup(s->logfile); 830 831 s->glfs = qemu_gluster_init(gconf, filename, options, errp); 832 if (!s->glfs) { 833 ret = -errno; 834 goto out; 835 } 836 837 #ifdef CONFIG_GLUSTERFS_XLATOR_OPT 838 /* Without this, if fsync fails for a recoverable reason (for instance, 839 * ENOSPC), gluster will dump its cache, preventing retries. This means 840 * almost certain data loss. Not all gluster versions support the 841 * 'resync-failed-syncs-after-fsync' key value, but there is no way to 842 * discover during runtime if it is supported (this api returns success for 843 * unknown key/value pairs) */ 844 ret = glfs_set_xlator_option(s->glfs, "*-write-behind", 845 "resync-failed-syncs-after-fsync", 846 "on"); 847 if (ret < 0) { 848 error_setg_errno(errp, errno, "Unable to set xlator key/value pair"); 849 ret = -errno; 850 goto out; 851 } 852 #endif 853 854 qemu_gluster_parse_flags(bdrv_flags, &open_flags); 855 856 s->fd = glfs_open(s->glfs, gconf->path, open_flags); 857 ret = s->fd ? 0 : -errno; 858 859 if (ret == -EACCES || ret == -EROFS) { 860 /* Try to degrade to read-only, but if it doesn't work, still use the 861 * normal error message. */ 862 bdrv_graph_rdlock_main_loop(); 863 if (bdrv_apply_auto_read_only(bs, NULL, NULL) == 0) { 864 open_flags = (open_flags & ~O_RDWR) | O_RDONLY; 865 s->fd = glfs_open(s->glfs, gconf->path, open_flags); 866 ret = s->fd ? 0 : -errno; 867 } 868 bdrv_graph_rdunlock_main_loop(); 869 } 870 871 s->supports_seek_data = qemu_gluster_test_seek(s->fd); 872 873 out: 874 qemu_opts_del(opts); 875 qapi_free_BlockdevOptionsGluster(gconf); 876 if (!ret) { 877 return ret; 878 } 879 g_free(s->logfile); 880 if (s->fd) { 881 glfs_close(s->fd); 882 } 883 884 glfs_clear_preopened(s->glfs); 885 886 return ret; 887 } 888 889 static void qemu_gluster_refresh_limits(BlockDriverState *bs, Error **errp) 890 { 891 bs->bl.max_transfer = GLUSTER_MAX_TRANSFER; 892 bs->bl.max_pdiscard = MIN(SIZE_MAX, INT64_MAX); 893 } 894 895 static int qemu_gluster_reopen_prepare(BDRVReopenState *state, 896 BlockReopenQueue *queue, Error **errp) 897 { 898 int ret = 0; 899 BDRVGlusterState *s; 900 BDRVGlusterReopenState *reop_s; 901 BlockdevOptionsGluster *gconf; 902 int open_flags = 0; 903 904 assert(state != NULL); 905 assert(state->bs != NULL); 906 907 s = state->bs->opaque; 908 909 state->opaque = g_new0(BDRVGlusterReopenState, 1); 910 reop_s = state->opaque; 911 912 qemu_gluster_parse_flags(state->flags, &open_flags); 913 914 gconf = g_new0(BlockdevOptionsGluster, 1); 915 gconf->debug = s->debug; 916 gconf->has_debug = true; 917 gconf->logfile = g_strdup(s->logfile); 918 919 /* 920 * If 'state->bs->exact_filename' is empty, 'state->options' should contain 921 * the JSON parameters already parsed. 922 */ 923 if (state->bs->exact_filename[0] != '\0') { 924 reop_s->glfs = qemu_gluster_init(gconf, state->bs->exact_filename, NULL, 925 errp); 926 } else { 927 reop_s->glfs = qemu_gluster_init(gconf, NULL, state->options, errp); 928 } 929 if (reop_s->glfs == NULL) { 930 ret = -errno; 931 goto exit; 932 } 933 934 #ifdef CONFIG_GLUSTERFS_XLATOR_OPT 935 ret = glfs_set_xlator_option(reop_s->glfs, "*-write-behind", 936 "resync-failed-syncs-after-fsync", "on"); 937 if (ret < 0) { 938 error_setg_errno(errp, errno, "Unable to set xlator key/value pair"); 939 ret = -errno; 940 goto exit; 941 } 942 #endif 943 944 reop_s->fd = glfs_open(reop_s->glfs, gconf->path, open_flags); 945 if (reop_s->fd == NULL) { 946 /* reops->glfs will be cleaned up in _abort */ 947 ret = -errno; 948 goto exit; 949 } 950 951 exit: 952 /* state->opaque will be freed in either the _abort or _commit */ 953 qapi_free_BlockdevOptionsGluster(gconf); 954 return ret; 955 } 956 957 static void qemu_gluster_reopen_commit(BDRVReopenState *state) 958 { 959 BDRVGlusterReopenState *reop_s = state->opaque; 960 BDRVGlusterState *s = state->bs->opaque; 961 962 963 /* close the old */ 964 if (s->fd) { 965 glfs_close(s->fd); 966 } 967 968 glfs_clear_preopened(s->glfs); 969 970 /* use the newly opened image / connection */ 971 s->fd = reop_s->fd; 972 s->glfs = reop_s->glfs; 973 974 g_free(state->opaque); 975 state->opaque = NULL; 976 977 return; 978 } 979 980 981 static void qemu_gluster_reopen_abort(BDRVReopenState *state) 982 { 983 BDRVGlusterReopenState *reop_s = state->opaque; 984 985 if (reop_s == NULL) { 986 return; 987 } 988 989 if (reop_s->fd) { 990 glfs_close(reop_s->fd); 991 } 992 993 glfs_clear_preopened(reop_s->glfs); 994 995 g_free(state->opaque); 996 state->opaque = NULL; 997 998 return; 999 } 1000 1001 #ifdef CONFIG_GLUSTERFS_ZEROFILL 1002 static coroutine_fn int qemu_gluster_co_pwrite_zeroes(BlockDriverState *bs, 1003 int64_t offset, 1004 int64_t bytes, 1005 BdrvRequestFlags flags) 1006 { 1007 int ret; 1008 GlusterAIOCB acb; 1009 BDRVGlusterState *s = bs->opaque; 1010 1011 acb.size = bytes; 1012 acb.ret = 0; 1013 acb.coroutine = qemu_coroutine_self(); 1014 acb.aio_context = bdrv_get_aio_context(bs); 1015 1016 ret = glfs_zerofill_async(s->fd, offset, bytes, gluster_finish_aiocb, &acb); 1017 if (ret < 0) { 1018 return -errno; 1019 } 1020 1021 qemu_coroutine_yield(); 1022 return acb.ret; 1023 } 1024 #endif 1025 1026 static int qemu_gluster_do_truncate(struct glfs_fd *fd, int64_t offset, 1027 PreallocMode prealloc, Error **errp) 1028 { 1029 int64_t current_length; 1030 1031 current_length = glfs_lseek(fd, 0, SEEK_END); 1032 if (current_length < 0) { 1033 error_setg_errno(errp, errno, "Failed to determine current size"); 1034 return -errno; 1035 } 1036 1037 if (current_length > offset && prealloc != PREALLOC_MODE_OFF) { 1038 error_setg(errp, "Cannot use preallocation for shrinking files"); 1039 return -ENOTSUP; 1040 } 1041 1042 if (current_length == offset) { 1043 return 0; 1044 } 1045 1046 switch (prealloc) { 1047 #ifdef CONFIG_GLUSTERFS_FALLOCATE 1048 case PREALLOC_MODE_FALLOC: 1049 if (glfs_fallocate(fd, 0, current_length, offset - current_length)) { 1050 error_setg_errno(errp, errno, "Could not preallocate data"); 1051 return -errno; 1052 } 1053 break; 1054 #endif /* CONFIG_GLUSTERFS_FALLOCATE */ 1055 #ifdef CONFIG_GLUSTERFS_ZEROFILL 1056 case PREALLOC_MODE_FULL: 1057 if (glfs_ftruncate(fd, offset)) { 1058 error_setg_errno(errp, errno, "Could not resize file"); 1059 return -errno; 1060 } 1061 if (glfs_zerofill(fd, current_length, offset - current_length)) { 1062 error_setg_errno(errp, errno, "Could not zerofill the new area"); 1063 return -errno; 1064 } 1065 break; 1066 #endif /* CONFIG_GLUSTERFS_ZEROFILL */ 1067 case PREALLOC_MODE_OFF: 1068 if (glfs_ftruncate(fd, offset)) { 1069 error_setg_errno(errp, errno, "Could not resize file"); 1070 return -errno; 1071 } 1072 break; 1073 default: 1074 error_setg(errp, "Unsupported preallocation mode: %s", 1075 PreallocMode_str(prealloc)); 1076 return -EINVAL; 1077 } 1078 1079 return 0; 1080 } 1081 1082 static int qemu_gluster_co_create(BlockdevCreateOptions *options, 1083 Error **errp) 1084 { 1085 BlockdevCreateOptionsGluster *opts = &options->u.gluster; 1086 struct glfs *glfs; 1087 struct glfs_fd *fd = NULL; 1088 int ret = 0; 1089 1090 assert(options->driver == BLOCKDEV_DRIVER_GLUSTER); 1091 1092 glfs = qemu_gluster_glfs_init(opts->location, errp); 1093 if (!glfs) { 1094 ret = -errno; 1095 goto out; 1096 } 1097 1098 fd = glfs_creat(glfs, opts->location->path, 1099 O_WRONLY | O_CREAT | O_TRUNC | O_BINARY, S_IRUSR | S_IWUSR); 1100 if (!fd) { 1101 ret = -errno; 1102 goto out; 1103 } 1104 1105 ret = qemu_gluster_do_truncate(fd, opts->size, opts->preallocation, errp); 1106 1107 out: 1108 if (fd) { 1109 if (glfs_close(fd) != 0 && ret == 0) { 1110 ret = -errno; 1111 } 1112 } 1113 glfs_clear_preopened(glfs); 1114 return ret; 1115 } 1116 1117 static int coroutine_fn qemu_gluster_co_create_opts(BlockDriver *drv, 1118 const char *filename, 1119 QemuOpts *opts, 1120 Error **errp) 1121 { 1122 BlockdevCreateOptions *options; 1123 BlockdevCreateOptionsGluster *gopts; 1124 BlockdevOptionsGluster *gconf; 1125 char *tmp = NULL; 1126 Error *local_err = NULL; 1127 int ret; 1128 1129 options = g_new0(BlockdevCreateOptions, 1); 1130 options->driver = BLOCKDEV_DRIVER_GLUSTER; 1131 gopts = &options->u.gluster; 1132 1133 gconf = g_new0(BlockdevOptionsGluster, 1); 1134 gopts->location = gconf; 1135 1136 gopts->size = ROUND_UP(qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0), 1137 BDRV_SECTOR_SIZE); 1138 1139 tmp = qemu_opt_get_del(opts, BLOCK_OPT_PREALLOC); 1140 gopts->preallocation = qapi_enum_parse(&PreallocMode_lookup, tmp, 1141 PREALLOC_MODE_OFF, &local_err); 1142 g_free(tmp); 1143 if (local_err) { 1144 error_propagate(errp, local_err); 1145 ret = -EINVAL; 1146 goto fail; 1147 } 1148 1149 gconf->debug = qemu_opt_get_number_del(opts, GLUSTER_OPT_DEBUG, 1150 GLUSTER_DEBUG_DEFAULT); 1151 if (gconf->debug < 0) { 1152 gconf->debug = 0; 1153 } else if (gconf->debug > GLUSTER_DEBUG_MAX) { 1154 gconf->debug = GLUSTER_DEBUG_MAX; 1155 } 1156 gconf->has_debug = true; 1157 1158 gconf->logfile = qemu_opt_get_del(opts, GLUSTER_OPT_LOGFILE); 1159 if (!gconf->logfile) { 1160 gconf->logfile = g_strdup(GLUSTER_LOGFILE_DEFAULT); 1161 } 1162 1163 ret = qemu_gluster_parse(gconf, filename, NULL, errp); 1164 if (ret < 0) { 1165 goto fail; 1166 } 1167 1168 ret = qemu_gluster_co_create(options, errp); 1169 if (ret < 0) { 1170 goto fail; 1171 } 1172 1173 ret = 0; 1174 fail: 1175 qapi_free_BlockdevCreateOptions(options); 1176 return ret; 1177 } 1178 1179 static coroutine_fn int qemu_gluster_co_rw(BlockDriverState *bs, 1180 int64_t sector_num, int nb_sectors, 1181 QEMUIOVector *qiov, int write) 1182 { 1183 int ret; 1184 GlusterAIOCB acb; 1185 BDRVGlusterState *s = bs->opaque; 1186 size_t size = nb_sectors * BDRV_SECTOR_SIZE; 1187 off_t offset = sector_num * BDRV_SECTOR_SIZE; 1188 1189 acb.size = size; 1190 acb.ret = 0; 1191 acb.coroutine = qemu_coroutine_self(); 1192 acb.aio_context = bdrv_get_aio_context(bs); 1193 1194 if (write) { 1195 ret = glfs_pwritev_async(s->fd, qiov->iov, qiov->niov, offset, 0, 1196 gluster_finish_aiocb, &acb); 1197 } else { 1198 ret = glfs_preadv_async(s->fd, qiov->iov, qiov->niov, offset, 0, 1199 gluster_finish_aiocb, &acb); 1200 } 1201 1202 if (ret < 0) { 1203 return -errno; 1204 } 1205 1206 qemu_coroutine_yield(); 1207 return acb.ret; 1208 } 1209 1210 static coroutine_fn int qemu_gluster_co_truncate(BlockDriverState *bs, 1211 int64_t offset, 1212 bool exact, 1213 PreallocMode prealloc, 1214 BdrvRequestFlags flags, 1215 Error **errp) 1216 { 1217 BDRVGlusterState *s = bs->opaque; 1218 return qemu_gluster_do_truncate(s->fd, offset, prealloc, errp); 1219 } 1220 1221 static coroutine_fn int qemu_gluster_co_readv(BlockDriverState *bs, 1222 int64_t sector_num, 1223 int nb_sectors, 1224 QEMUIOVector *qiov) 1225 { 1226 return qemu_gluster_co_rw(bs, sector_num, nb_sectors, qiov, 0); 1227 } 1228 1229 static coroutine_fn int qemu_gluster_co_writev(BlockDriverState *bs, 1230 int64_t sector_num, 1231 int nb_sectors, 1232 QEMUIOVector *qiov, 1233 int flags) 1234 { 1235 return qemu_gluster_co_rw(bs, sector_num, nb_sectors, qiov, 1); 1236 } 1237 1238 static void qemu_gluster_close(BlockDriverState *bs) 1239 { 1240 BDRVGlusterState *s = bs->opaque; 1241 1242 g_free(s->logfile); 1243 if (s->fd) { 1244 glfs_close(s->fd); 1245 s->fd = NULL; 1246 } 1247 glfs_clear_preopened(s->glfs); 1248 } 1249 1250 static coroutine_fn int qemu_gluster_co_flush_to_disk(BlockDriverState *bs) 1251 { 1252 int ret; 1253 GlusterAIOCB acb; 1254 BDRVGlusterState *s = bs->opaque; 1255 1256 acb.size = 0; 1257 acb.ret = 0; 1258 acb.coroutine = qemu_coroutine_self(); 1259 acb.aio_context = bdrv_get_aio_context(bs); 1260 1261 ret = glfs_fsync_async(s->fd, gluster_finish_aiocb, &acb); 1262 if (ret < 0) { 1263 ret = -errno; 1264 goto error; 1265 } 1266 1267 qemu_coroutine_yield(); 1268 if (acb.ret < 0) { 1269 ret = acb.ret; 1270 goto error; 1271 } 1272 1273 return acb.ret; 1274 1275 error: 1276 /* Some versions of Gluster (3.5.6 -> 3.5.8?) will not retain its cache 1277 * after a fsync failure, so we have no way of allowing the guest to safely 1278 * continue. Gluster versions prior to 3.5.6 don't retain the cache 1279 * either, but will invalidate the fd on error, so this is again our only 1280 * option. 1281 * 1282 * The 'resync-failed-syncs-after-fsync' xlator option for the 1283 * write-behind cache will cause later gluster versions to retain its 1284 * cache after error, so long as the fd remains open. However, we 1285 * currently have no way of knowing if this option is supported. 1286 * 1287 * TODO: Once gluster provides a way for us to determine if the option 1288 * is supported, bypass the closure and setting drv to NULL. */ 1289 qemu_gluster_close(bs); 1290 bs->drv = NULL; 1291 return ret; 1292 } 1293 1294 #ifdef CONFIG_GLUSTERFS_DISCARD 1295 static coroutine_fn int qemu_gluster_co_pdiscard(BlockDriverState *bs, 1296 int64_t offset, int64_t bytes) 1297 { 1298 int ret; 1299 GlusterAIOCB acb; 1300 BDRVGlusterState *s = bs->opaque; 1301 1302 assert(bytes <= SIZE_MAX); /* rely on max_pdiscard */ 1303 1304 acb.size = 0; 1305 acb.ret = 0; 1306 acb.coroutine = qemu_coroutine_self(); 1307 acb.aio_context = bdrv_get_aio_context(bs); 1308 1309 ret = glfs_discard_async(s->fd, offset, bytes, gluster_finish_aiocb, &acb); 1310 if (ret < 0) { 1311 return -errno; 1312 } 1313 1314 qemu_coroutine_yield(); 1315 return acb.ret; 1316 } 1317 #endif 1318 1319 static int64_t coroutine_fn qemu_gluster_co_getlength(BlockDriverState *bs) 1320 { 1321 BDRVGlusterState *s = bs->opaque; 1322 int64_t ret; 1323 1324 ret = glfs_lseek(s->fd, 0, SEEK_END); 1325 if (ret < 0) { 1326 return -errno; 1327 } else { 1328 return ret; 1329 } 1330 } 1331 1332 static int64_t coroutine_fn 1333 qemu_gluster_co_get_allocated_file_size(BlockDriverState *bs) 1334 { 1335 BDRVGlusterState *s = bs->opaque; 1336 struct stat st; 1337 int ret; 1338 1339 ret = glfs_fstat(s->fd, &st); 1340 if (ret < 0) { 1341 return -errno; 1342 } else { 1343 return st.st_blocks * 512; 1344 } 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 a soft cap for 'pnum'. If the information is free, 'pnum' may 1464 * well exceed it. 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 assert(QEMU_IS_ALIGNED(offset | bytes, bs->bl.request_alignment)); 1481 1482 if (!s->fd) { 1483 return ret; 1484 } 1485 1486 if (!want_zero) { 1487 *pnum = bytes; 1488 *map = offset; 1489 *file = bs; 1490 return BDRV_BLOCK_DATA | BDRV_BLOCK_OFFSET_VALID; 1491 } 1492 1493 ret = find_allocation(bs, offset, &data, &hole); 1494 if (ret == -ENXIO) { 1495 /* Trailing hole */ 1496 *pnum = bytes; 1497 ret = BDRV_BLOCK_ZERO; 1498 } else if (ret < 0) { 1499 /* No info available, so pretend there are no holes */ 1500 *pnum = bytes; 1501 ret = BDRV_BLOCK_DATA; 1502 } else if (data == offset) { 1503 /* On a data extent, compute bytes to the end of the extent, 1504 * possibly including a partial sector at EOF. */ 1505 *pnum = hole - offset; 1506 1507 /* 1508 * We are not allowed to return partial sectors, though, so 1509 * round up if necessary. 1510 */ 1511 if (!QEMU_IS_ALIGNED(*pnum, bs->bl.request_alignment)) { 1512 int64_t file_length = qemu_gluster_co_getlength(bs); 1513 if (file_length > 0) { 1514 /* Ignore errors, this is just a safeguard */ 1515 assert(hole == file_length); 1516 } 1517 *pnum = ROUND_UP(*pnum, bs->bl.request_alignment); 1518 } 1519 1520 ret = BDRV_BLOCK_DATA; 1521 } else { 1522 /* On a hole, compute bytes to the beginning of the next extent. */ 1523 assert(hole == offset); 1524 *pnum = data - offset; 1525 ret = BDRV_BLOCK_ZERO; 1526 } 1527 1528 *map = offset; 1529 *file = bs; 1530 1531 return ret | BDRV_BLOCK_OFFSET_VALID; 1532 } 1533 1534 1535 static const char *const gluster_strong_open_opts[] = { 1536 GLUSTER_OPT_VOLUME, 1537 GLUSTER_OPT_PATH, 1538 GLUSTER_OPT_TYPE, 1539 GLUSTER_OPT_SERVER_PATTERN, 1540 GLUSTER_OPT_HOST, 1541 GLUSTER_OPT_PORT, 1542 GLUSTER_OPT_TO, 1543 GLUSTER_OPT_IPV4, 1544 GLUSTER_OPT_IPV6, 1545 GLUSTER_OPT_SOCKET, 1546 1547 NULL 1548 }; 1549 1550 static BlockDriver bdrv_gluster = { 1551 .format_name = "gluster", 1552 .protocol_name = "gluster", 1553 .instance_size = sizeof(BDRVGlusterState), 1554 .bdrv_file_open = qemu_gluster_open, 1555 .bdrv_reopen_prepare = qemu_gluster_reopen_prepare, 1556 .bdrv_reopen_commit = qemu_gluster_reopen_commit, 1557 .bdrv_reopen_abort = qemu_gluster_reopen_abort, 1558 .bdrv_close = qemu_gluster_close, 1559 .bdrv_co_create = qemu_gluster_co_create, 1560 .bdrv_co_create_opts = qemu_gluster_co_create_opts, 1561 .bdrv_co_getlength = qemu_gluster_co_getlength, 1562 .bdrv_co_get_allocated_file_size = qemu_gluster_co_get_allocated_file_size, 1563 .bdrv_co_truncate = qemu_gluster_co_truncate, 1564 .bdrv_co_readv = qemu_gluster_co_readv, 1565 .bdrv_co_writev = qemu_gluster_co_writev, 1566 .bdrv_co_flush_to_disk = qemu_gluster_co_flush_to_disk, 1567 #ifdef CONFIG_GLUSTERFS_DISCARD 1568 .bdrv_co_pdiscard = qemu_gluster_co_pdiscard, 1569 #endif 1570 #ifdef CONFIG_GLUSTERFS_ZEROFILL 1571 .bdrv_co_pwrite_zeroes = qemu_gluster_co_pwrite_zeroes, 1572 #endif 1573 .bdrv_co_block_status = qemu_gluster_co_block_status, 1574 .bdrv_refresh_limits = qemu_gluster_refresh_limits, 1575 .create_opts = &qemu_gluster_create_opts, 1576 .strong_runtime_opts = gluster_strong_open_opts, 1577 }; 1578 1579 static BlockDriver bdrv_gluster_tcp = { 1580 .format_name = "gluster", 1581 .protocol_name = "gluster+tcp", 1582 .instance_size = sizeof(BDRVGlusterState), 1583 .bdrv_file_open = qemu_gluster_open, 1584 .bdrv_reopen_prepare = qemu_gluster_reopen_prepare, 1585 .bdrv_reopen_commit = qemu_gluster_reopen_commit, 1586 .bdrv_reopen_abort = qemu_gluster_reopen_abort, 1587 .bdrv_close = qemu_gluster_close, 1588 .bdrv_co_create = qemu_gluster_co_create, 1589 .bdrv_co_create_opts = qemu_gluster_co_create_opts, 1590 .bdrv_co_getlength = qemu_gluster_co_getlength, 1591 .bdrv_co_get_allocated_file_size = qemu_gluster_co_get_allocated_file_size, 1592 .bdrv_co_truncate = qemu_gluster_co_truncate, 1593 .bdrv_co_readv = qemu_gluster_co_readv, 1594 .bdrv_co_writev = qemu_gluster_co_writev, 1595 .bdrv_co_flush_to_disk = qemu_gluster_co_flush_to_disk, 1596 #ifdef CONFIG_GLUSTERFS_DISCARD 1597 .bdrv_co_pdiscard = qemu_gluster_co_pdiscard, 1598 #endif 1599 #ifdef CONFIG_GLUSTERFS_ZEROFILL 1600 .bdrv_co_pwrite_zeroes = qemu_gluster_co_pwrite_zeroes, 1601 #endif 1602 .bdrv_co_block_status = qemu_gluster_co_block_status, 1603 .bdrv_refresh_limits = qemu_gluster_refresh_limits, 1604 .create_opts = &qemu_gluster_create_opts, 1605 .strong_runtime_opts = gluster_strong_open_opts, 1606 }; 1607 1608 static BlockDriver bdrv_gluster_unix = { 1609 .format_name = "gluster", 1610 .protocol_name = "gluster+unix", 1611 .instance_size = sizeof(BDRVGlusterState), 1612 .bdrv_file_open = qemu_gluster_open, 1613 .bdrv_reopen_prepare = qemu_gluster_reopen_prepare, 1614 .bdrv_reopen_commit = qemu_gluster_reopen_commit, 1615 .bdrv_reopen_abort = qemu_gluster_reopen_abort, 1616 .bdrv_close = qemu_gluster_close, 1617 .bdrv_co_create = qemu_gluster_co_create, 1618 .bdrv_co_create_opts = qemu_gluster_co_create_opts, 1619 .bdrv_co_getlength = qemu_gluster_co_getlength, 1620 .bdrv_co_get_allocated_file_size = qemu_gluster_co_get_allocated_file_size, 1621 .bdrv_co_truncate = qemu_gluster_co_truncate, 1622 .bdrv_co_readv = qemu_gluster_co_readv, 1623 .bdrv_co_writev = qemu_gluster_co_writev, 1624 .bdrv_co_flush_to_disk = qemu_gluster_co_flush_to_disk, 1625 #ifdef CONFIG_GLUSTERFS_DISCARD 1626 .bdrv_co_pdiscard = qemu_gluster_co_pdiscard, 1627 #endif 1628 #ifdef CONFIG_GLUSTERFS_ZEROFILL 1629 .bdrv_co_pwrite_zeroes = qemu_gluster_co_pwrite_zeroes, 1630 #endif 1631 .bdrv_co_block_status = qemu_gluster_co_block_status, 1632 .bdrv_refresh_limits = qemu_gluster_refresh_limits, 1633 .create_opts = &qemu_gluster_create_opts, 1634 .strong_runtime_opts = gluster_strong_open_opts, 1635 }; 1636 1637 static void bdrv_gluster_init(void) 1638 { 1639 bdrv_register(&bdrv_gluster_unix); 1640 bdrv_register(&bdrv_gluster_tcp); 1641 bdrv_register(&bdrv_gluster); 1642 } 1643 1644 block_init(bdrv_gluster_init); 1645