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 const char *ptr; 518 int i, type, num_servers; 519 520 /* create opts info from runtime_json_opts list */ 521 opts = qemu_opts_create(&runtime_json_opts, NULL, 0, &error_abort); 522 if (!qemu_opts_absorb_qdict(opts, options, errp)) { 523 goto out; 524 } 525 526 num_servers = qdict_array_entries(options, GLUSTER_OPT_SERVER_PATTERN); 527 if (num_servers < 1) { 528 error_setg(&local_err, QERR_MISSING_PARAMETER, "server"); 529 goto out; 530 } 531 532 ptr = qemu_opt_get(opts, GLUSTER_OPT_VOLUME); 533 if (!ptr) { 534 error_setg(&local_err, QERR_MISSING_PARAMETER, GLUSTER_OPT_VOLUME); 535 goto out; 536 } 537 gconf->volume = g_strdup(ptr); 538 539 ptr = qemu_opt_get(opts, GLUSTER_OPT_PATH); 540 if (!ptr) { 541 error_setg(&local_err, QERR_MISSING_PARAMETER, GLUSTER_OPT_PATH); 542 goto out; 543 } 544 gconf->path = g_strdup(ptr); 545 qemu_opts_del(opts); 546 tail = &gconf->server; 547 548 for (i = 0; i < num_servers; i++) { 549 g_autofree char *str = g_strdup_printf(GLUSTER_OPT_SERVER_PATTERN"%d.", 550 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 } 662 663 return 0; 664 665 out: 666 error_propagate(errp, local_err); 667 qapi_free_SocketAddress(gsconf); 668 qemu_opts_del(opts); 669 qobject_unref(backing_options); 670 errno = EINVAL; 671 return -errno; 672 } 673 674 /* Converts options given in @filename and the @options QDict into the QAPI 675 * object @gconf. */ 676 static int qemu_gluster_parse(BlockdevOptionsGluster *gconf, 677 const char *filename, 678 QDict *options, Error **errp) 679 { 680 int ret; 681 if (filename) { 682 ret = qemu_gluster_parse_uri(gconf, filename); 683 if (ret < 0) { 684 error_setg(errp, "invalid URI %s", filename); 685 error_append_hint(errp, "Usage: file=gluster[+transport]://" 686 "[host[:port]]volume/path[?socket=...]" 687 "[,file.debug=N]" 688 "[,file.logfile=/path/filename.log]\n"); 689 return ret; 690 } 691 } else { 692 ret = qemu_gluster_parse_json(gconf, options, errp); 693 if (ret < 0) { 694 error_append_hint(errp, "Usage: " 695 "-drive driver=qcow2,file.driver=gluster," 696 "file.volume=testvol,file.path=/path/a.qcow2" 697 "[,file.debug=9]" 698 "[,file.logfile=/path/filename.log]," 699 "file.server.0.type=inet," 700 "file.server.0.host=1.2.3.4," 701 "file.server.0.port=24007," 702 "file.server.1.transport=unix," 703 "file.server.1.path=/var/run/glusterd.socket ..." 704 "\n"); 705 return ret; 706 } 707 } 708 709 return 0; 710 } 711 712 static struct glfs *qemu_gluster_init(BlockdevOptionsGluster *gconf, 713 const char *filename, 714 QDict *options, Error **errp) 715 { 716 int ret; 717 718 ret = qemu_gluster_parse(gconf, filename, options, errp); 719 if (ret < 0) { 720 errno = -ret; 721 return NULL; 722 } 723 724 return qemu_gluster_glfs_init(gconf, errp); 725 } 726 727 /* 728 * AIO callback routine called from GlusterFS thread. 729 */ 730 static void gluster_finish_aiocb(struct glfs_fd *fd, ssize_t ret, 731 #ifdef CONFIG_GLUSTERFS_IOCB_HAS_STAT 732 struct glfs_stat *pre, struct glfs_stat *post, 733 #endif 734 void *arg) 735 { 736 GlusterAIOCB *acb = (GlusterAIOCB *)arg; 737 738 if (!ret || ret == acb->size) { 739 acb->ret = 0; /* Success */ 740 } else if (ret < 0) { 741 acb->ret = -errno; /* Read/Write failed */ 742 } else { 743 acb->ret = -EIO; /* Partial read/write - fail it */ 744 } 745 746 aio_co_schedule(acb->aio_context, acb->coroutine); 747 } 748 749 static void qemu_gluster_parse_flags(int bdrv_flags, int *open_flags) 750 { 751 assert(open_flags != NULL); 752 753 *open_flags |= O_BINARY; 754 755 if (bdrv_flags & BDRV_O_RDWR) { 756 *open_flags |= O_RDWR; 757 } else { 758 *open_flags |= O_RDONLY; 759 } 760 761 if ((bdrv_flags & BDRV_O_NOCACHE)) { 762 *open_flags |= O_DIRECT; 763 } 764 } 765 766 /* 767 * Do SEEK_DATA/HOLE to detect if it is functional. Older broken versions of 768 * gfapi incorrectly return the current offset when SEEK_DATA/HOLE is used. 769 * - Corrected versions return -1 and set errno to EINVAL. 770 * - Versions that support SEEK_DATA/HOLE correctly, will return -1 and set 771 * errno to ENXIO when SEEK_DATA is called with a position of EOF. 772 */ 773 static bool qemu_gluster_test_seek(struct glfs_fd *fd) 774 { 775 off_t ret = 0; 776 777 #if defined SEEK_HOLE && defined SEEK_DATA 778 off_t eof; 779 780 eof = glfs_lseek(fd, 0, SEEK_END); 781 if (eof < 0) { 782 /* this should never occur */ 783 return false; 784 } 785 786 /* this should always fail with ENXIO if SEEK_DATA is supported */ 787 ret = glfs_lseek(fd, eof, SEEK_DATA); 788 #endif 789 790 return (ret < 0) && (errno == ENXIO); 791 } 792 793 static int qemu_gluster_open(BlockDriverState *bs, QDict *options, 794 int bdrv_flags, Error **errp) 795 { 796 BDRVGlusterState *s = bs->opaque; 797 int open_flags = 0; 798 int ret = 0; 799 BlockdevOptionsGluster *gconf = NULL; 800 QemuOpts *opts; 801 const char *filename, *logfile; 802 803 opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort); 804 if (!qemu_opts_absorb_qdict(opts, options, errp)) { 805 ret = -EINVAL; 806 goto out; 807 } 808 809 warn_report_once("'gluster' is deprecated"); 810 811 filename = qemu_opt_get(opts, GLUSTER_OPT_FILENAME); 812 813 s->debug = qemu_opt_get_number(opts, GLUSTER_OPT_DEBUG, 814 GLUSTER_DEBUG_DEFAULT); 815 if (s->debug < 0) { 816 s->debug = 0; 817 } else if (s->debug > GLUSTER_DEBUG_MAX) { 818 s->debug = GLUSTER_DEBUG_MAX; 819 } 820 821 gconf = g_new0(BlockdevOptionsGluster, 1); 822 gconf->debug = s->debug; 823 gconf->has_debug = true; 824 825 logfile = qemu_opt_get(opts, GLUSTER_OPT_LOGFILE); 826 s->logfile = g_strdup(logfile ? logfile : GLUSTER_LOGFILE_DEFAULT); 827 828 gconf->logfile = g_strdup(s->logfile); 829 830 s->glfs = qemu_gluster_init(gconf, filename, options, errp); 831 if (!s->glfs) { 832 ret = -errno; 833 goto out; 834 } 835 836 #ifdef CONFIG_GLUSTERFS_XLATOR_OPT 837 /* Without this, if fsync fails for a recoverable reason (for instance, 838 * ENOSPC), gluster will dump its cache, preventing retries. This means 839 * almost certain data loss. Not all gluster versions support the 840 * 'resync-failed-syncs-after-fsync' key value, but there is no way to 841 * discover during runtime if it is supported (this api returns success for 842 * unknown key/value pairs) */ 843 ret = glfs_set_xlator_option(s->glfs, "*-write-behind", 844 "resync-failed-syncs-after-fsync", 845 "on"); 846 if (ret < 0) { 847 error_setg_errno(errp, errno, "Unable to set xlator key/value pair"); 848 ret = -errno; 849 goto out; 850 } 851 #endif 852 853 qemu_gluster_parse_flags(bdrv_flags, &open_flags); 854 855 s->fd = glfs_open(s->glfs, gconf->path, open_flags); 856 ret = s->fd ? 0 : -errno; 857 858 if (ret == -EACCES || ret == -EROFS) { 859 /* Try to degrade to read-only, but if it doesn't work, still use the 860 * normal error message. */ 861 bdrv_graph_rdlock_main_loop(); 862 if (bdrv_apply_auto_read_only(bs, NULL, NULL) == 0) { 863 open_flags = (open_flags & ~O_RDWR) | O_RDONLY; 864 s->fd = glfs_open(s->glfs, gconf->path, open_flags); 865 ret = s->fd ? 0 : -errno; 866 } 867 bdrv_graph_rdunlock_main_loop(); 868 } 869 870 s->supports_seek_data = qemu_gluster_test_seek(s->fd); 871 872 out: 873 qemu_opts_del(opts); 874 qapi_free_BlockdevOptionsGluster(gconf); 875 if (!ret) { 876 return ret; 877 } 878 g_free(s->logfile); 879 if (s->fd) { 880 glfs_close(s->fd); 881 } 882 883 glfs_clear_preopened(s->glfs); 884 885 return ret; 886 } 887 888 static void qemu_gluster_refresh_limits(BlockDriverState *bs, Error **errp) 889 { 890 bs->bl.max_transfer = GLUSTER_MAX_TRANSFER; 891 bs->bl.max_pdiscard = MIN(SIZE_MAX, INT64_MAX); 892 } 893 894 static int qemu_gluster_reopen_prepare(BDRVReopenState *state, 895 BlockReopenQueue *queue, Error **errp) 896 { 897 int ret = 0; 898 BDRVGlusterState *s; 899 BDRVGlusterReopenState *reop_s; 900 BlockdevOptionsGluster *gconf; 901 int open_flags = 0; 902 903 assert(state != NULL); 904 assert(state->bs != NULL); 905 906 s = state->bs->opaque; 907 908 state->opaque = g_new0(BDRVGlusterReopenState, 1); 909 reop_s = state->opaque; 910 911 qemu_gluster_parse_flags(state->flags, &open_flags); 912 913 gconf = g_new0(BlockdevOptionsGluster, 1); 914 gconf->debug = s->debug; 915 gconf->has_debug = true; 916 gconf->logfile = g_strdup(s->logfile); 917 918 /* 919 * If 'state->bs->exact_filename' is empty, 'state->options' should contain 920 * the JSON parameters already parsed. 921 */ 922 if (state->bs->exact_filename[0] != '\0') { 923 reop_s->glfs = qemu_gluster_init(gconf, state->bs->exact_filename, NULL, 924 errp); 925 } else { 926 reop_s->glfs = qemu_gluster_init(gconf, NULL, state->options, errp); 927 } 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 int64_t bytes, 1004 BdrvRequestFlags flags) 1005 { 1006 int ret; 1007 GlusterAIOCB acb; 1008 BDRVGlusterState *s = bs->opaque; 1009 1010 acb.size = bytes; 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, bytes, 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(BlockDriver *drv, 1117 const char *filename, 1118 QemuOpts *opts, 1119 Error **errp) 1120 { 1121 BlockdevCreateOptions *options; 1122 BlockdevCreateOptionsGluster *gopts; 1123 BlockdevOptionsGluster *gconf; 1124 char *tmp = NULL; 1125 Error *local_err = NULL; 1126 int ret; 1127 1128 options = g_new0(BlockdevCreateOptions, 1); 1129 options->driver = BLOCKDEV_DRIVER_GLUSTER; 1130 gopts = &options->u.gluster; 1131 1132 gconf = g_new0(BlockdevOptionsGluster, 1); 1133 gopts->location = gconf; 1134 1135 gopts->size = ROUND_UP(qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0), 1136 BDRV_SECTOR_SIZE); 1137 1138 tmp = qemu_opt_get_del(opts, BLOCK_OPT_PREALLOC); 1139 gopts->preallocation = qapi_enum_parse(&PreallocMode_lookup, tmp, 1140 PREALLOC_MODE_OFF, &local_err); 1141 g_free(tmp); 1142 if (local_err) { 1143 error_propagate(errp, local_err); 1144 ret = -EINVAL; 1145 goto fail; 1146 } 1147 1148 gconf->debug = qemu_opt_get_number_del(opts, GLUSTER_OPT_DEBUG, 1149 GLUSTER_DEBUG_DEFAULT); 1150 if (gconf->debug < 0) { 1151 gconf->debug = 0; 1152 } else if (gconf->debug > GLUSTER_DEBUG_MAX) { 1153 gconf->debug = GLUSTER_DEBUG_MAX; 1154 } 1155 gconf->has_debug = true; 1156 1157 gconf->logfile = qemu_opt_get_del(opts, GLUSTER_OPT_LOGFILE); 1158 if (!gconf->logfile) { 1159 gconf->logfile = g_strdup(GLUSTER_LOGFILE_DEFAULT); 1160 } 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 bool exact, 1212 PreallocMode prealloc, 1213 BdrvRequestFlags flags, 1214 Error **errp) 1215 { 1216 BDRVGlusterState *s = bs->opaque; 1217 return qemu_gluster_do_truncate(s->fd, offset, prealloc, errp); 1218 } 1219 1220 static coroutine_fn int qemu_gluster_co_readv(BlockDriverState *bs, 1221 int64_t sector_num, 1222 int nb_sectors, 1223 QEMUIOVector *qiov) 1224 { 1225 return qemu_gluster_co_rw(bs, sector_num, nb_sectors, qiov, 0); 1226 } 1227 1228 static coroutine_fn int qemu_gluster_co_writev(BlockDriverState *bs, 1229 int64_t sector_num, 1230 int nb_sectors, 1231 QEMUIOVector *qiov, 1232 int flags) 1233 { 1234 return qemu_gluster_co_rw(bs, sector_num, nb_sectors, qiov, 1); 1235 } 1236 1237 static void qemu_gluster_close(BlockDriverState *bs) 1238 { 1239 BDRVGlusterState *s = bs->opaque; 1240 1241 g_free(s->logfile); 1242 if (s->fd) { 1243 glfs_close(s->fd); 1244 s->fd = NULL; 1245 } 1246 glfs_clear_preopened(s->glfs); 1247 } 1248 1249 static coroutine_fn int qemu_gluster_co_flush_to_disk(BlockDriverState *bs) 1250 { 1251 int ret; 1252 GlusterAIOCB acb; 1253 BDRVGlusterState *s = bs->opaque; 1254 1255 acb.size = 0; 1256 acb.ret = 0; 1257 acb.coroutine = qemu_coroutine_self(); 1258 acb.aio_context = bdrv_get_aio_context(bs); 1259 1260 ret = glfs_fsync_async(s->fd, gluster_finish_aiocb, &acb); 1261 if (ret < 0) { 1262 ret = -errno; 1263 goto error; 1264 } 1265 1266 qemu_coroutine_yield(); 1267 if (acb.ret < 0) { 1268 ret = acb.ret; 1269 goto error; 1270 } 1271 1272 return acb.ret; 1273 1274 error: 1275 /* Some versions of Gluster (3.5.6 -> 3.5.8?) will not retain its cache 1276 * after a fsync failure, so we have no way of allowing the guest to safely 1277 * continue. Gluster versions prior to 3.5.6 don't retain the cache 1278 * either, but will invalidate the fd on error, so this is again our only 1279 * option. 1280 * 1281 * The 'resync-failed-syncs-after-fsync' xlator option for the 1282 * write-behind cache will cause later gluster versions to retain its 1283 * cache after error, so long as the fd remains open. However, we 1284 * currently have no way of knowing if this option is supported. 1285 * 1286 * TODO: Once gluster provides a way for us to determine if the option 1287 * is supported, bypass the closure and setting drv to NULL. */ 1288 qemu_gluster_close(bs); 1289 bs->drv = NULL; 1290 return ret; 1291 } 1292 1293 #ifdef CONFIG_GLUSTERFS_DISCARD 1294 static coroutine_fn int qemu_gluster_co_pdiscard(BlockDriverState *bs, 1295 int64_t offset, int64_t bytes) 1296 { 1297 int ret; 1298 GlusterAIOCB acb; 1299 BDRVGlusterState *s = bs->opaque; 1300 1301 assert(bytes <= SIZE_MAX); /* rely on max_pdiscard */ 1302 1303 acb.size = 0; 1304 acb.ret = 0; 1305 acb.coroutine = qemu_coroutine_self(); 1306 acb.aio_context = bdrv_get_aio_context(bs); 1307 1308 ret = glfs_discard_async(s->fd, offset, bytes, gluster_finish_aiocb, &acb); 1309 if (ret < 0) { 1310 return -errno; 1311 } 1312 1313 qemu_coroutine_yield(); 1314 return acb.ret; 1315 } 1316 #endif 1317 1318 static int64_t coroutine_fn qemu_gluster_co_getlength(BlockDriverState *bs) 1319 { 1320 BDRVGlusterState *s = bs->opaque; 1321 int64_t ret; 1322 1323 ret = glfs_lseek(s->fd, 0, SEEK_END); 1324 if (ret < 0) { 1325 return -errno; 1326 } else { 1327 return ret; 1328 } 1329 } 1330 1331 static int64_t coroutine_fn 1332 qemu_gluster_co_get_allocated_file_size(BlockDriverState *bs) 1333 { 1334 BDRVGlusterState *s = bs->opaque; 1335 struct stat st; 1336 int ret; 1337 1338 ret = glfs_fstat(s->fd, &st); 1339 if (ret < 0) { 1340 return -errno; 1341 } else { 1342 return st.st_blocks * 512; 1343 } 1344 } 1345 1346 /* 1347 * Find allocation range in @bs around offset @start. 1348 * May change underlying file descriptor's file offset. 1349 * If @start is not in a hole, store @start in @data, and the 1350 * beginning of the next hole in @hole, and return 0. 1351 * If @start is in a non-trailing hole, store @start in @hole and the 1352 * beginning of the next non-hole in @data, and return 0. 1353 * If @start is in a trailing hole or beyond EOF, return -ENXIO. 1354 * If we can't find out, return a negative errno other than -ENXIO. 1355 * 1356 * (Shamefully copied from file-posix.c, only minuscule adaptions.) 1357 */ 1358 static int find_allocation(BlockDriverState *bs, off_t start, 1359 off_t *data, off_t *hole) 1360 { 1361 BDRVGlusterState *s = bs->opaque; 1362 1363 if (!s->supports_seek_data) { 1364 goto exit; 1365 } 1366 1367 #if defined SEEK_HOLE && defined SEEK_DATA 1368 off_t offs; 1369 1370 /* 1371 * SEEK_DATA cases: 1372 * D1. offs == start: start is in data 1373 * D2. offs > start: start is in a hole, next data at offs 1374 * D3. offs < 0, errno = ENXIO: either start is in a trailing hole 1375 * or start is beyond EOF 1376 * If the latter happens, the file has been truncated behind 1377 * our back since we opened it. All bets are off then. 1378 * Treating like a trailing hole is simplest. 1379 * D4. offs < 0, errno != ENXIO: we learned nothing 1380 */ 1381 offs = glfs_lseek(s->fd, start, SEEK_DATA); 1382 if (offs < 0) { 1383 return -errno; /* D3 or D4 */ 1384 } 1385 1386 if (offs < start) { 1387 /* This is not a valid return by lseek(). We are safe to just return 1388 * -EIO in this case, and we'll treat it like D4. Unfortunately some 1389 * versions of gluster server will return offs < start, so an assert 1390 * here will unnecessarily abort QEMU. */ 1391 return -EIO; 1392 } 1393 1394 if (offs > start) { 1395 /* D2: in hole, next data at offs */ 1396 *hole = start; 1397 *data = offs; 1398 return 0; 1399 } 1400 1401 /* D1: in data, end not yet known */ 1402 1403 /* 1404 * SEEK_HOLE cases: 1405 * H1. offs == start: start is in a hole 1406 * If this happens here, a hole has been dug behind our back 1407 * since the previous lseek(). 1408 * H2. offs > start: either start is in data, next hole at offs, 1409 * or start is in trailing hole, EOF at offs 1410 * Linux treats trailing holes like any other hole: offs == 1411 * start. Solaris seeks to EOF instead: offs > start (blech). 1412 * If that happens here, a hole has been dug behind our back 1413 * since the previous lseek(). 1414 * H3. offs < 0, errno = ENXIO: start is beyond EOF 1415 * If this happens, the file has been truncated behind our 1416 * back since we opened it. Treat it like a trailing hole. 1417 * H4. offs < 0, errno != ENXIO: we learned nothing 1418 * Pretend we know nothing at all, i.e. "forget" about D1. 1419 */ 1420 offs = glfs_lseek(s->fd, start, SEEK_HOLE); 1421 if (offs < 0) { 1422 return -errno; /* D1 and (H3 or H4) */ 1423 } 1424 1425 if (offs < start) { 1426 /* This is not a valid return by lseek(). We are safe to just return 1427 * -EIO in this case, and we'll treat it like H4. Unfortunately some 1428 * versions of gluster server will return offs < start, so an assert 1429 * here will unnecessarily abort QEMU. */ 1430 return -EIO; 1431 } 1432 1433 if (offs > start) { 1434 /* 1435 * D1 and H2: either in data, next hole at offs, or it was in 1436 * data but is now in a trailing hole. In the latter case, 1437 * all bets are off. Treating it as if it there was data all 1438 * the way to EOF is safe, so simply do that. 1439 */ 1440 *data = start; 1441 *hole = offs; 1442 return 0; 1443 } 1444 1445 /* D1 and H1 */ 1446 return -EBUSY; 1447 #endif 1448 1449 exit: 1450 return -ENOTSUP; 1451 } 1452 1453 /* 1454 * Returns the allocation status of the specified offset. 1455 * 1456 * The block layer guarantees 'offset' and 'bytes' are within bounds. 1457 * 1458 * 'pnum' is set to the number of bytes (including and immediately following 1459 * the specified offset) that are known to be in the same 1460 * allocated/unallocated state. 1461 * 1462 * 'bytes' is a soft cap for 'pnum'. If the information is free, 'pnum' may 1463 * well exceed it. 1464 * 1465 * (Based on raw_co_block_status() from file-posix.c.) 1466 */ 1467 static int coroutine_fn qemu_gluster_co_block_status(BlockDriverState *bs, 1468 bool want_zero, 1469 int64_t offset, 1470 int64_t bytes, 1471 int64_t *pnum, 1472 int64_t *map, 1473 BlockDriverState **file) 1474 { 1475 BDRVGlusterState *s = bs->opaque; 1476 off_t data = 0, hole = 0; 1477 int ret = -EINVAL; 1478 1479 assert(QEMU_IS_ALIGNED(offset | bytes, bs->bl.request_alignment)); 1480 1481 if (!s->fd) { 1482 return ret; 1483 } 1484 1485 if (!want_zero) { 1486 *pnum = bytes; 1487 *map = offset; 1488 *file = bs; 1489 return BDRV_BLOCK_DATA | BDRV_BLOCK_OFFSET_VALID; 1490 } 1491 1492 ret = find_allocation(bs, offset, &data, &hole); 1493 if (ret == -ENXIO) { 1494 /* Trailing hole */ 1495 *pnum = bytes; 1496 ret = BDRV_BLOCK_ZERO; 1497 } else if (ret < 0) { 1498 /* No info available, so pretend there are no holes */ 1499 *pnum = bytes; 1500 ret = BDRV_BLOCK_DATA; 1501 } else if (data == offset) { 1502 /* On a data extent, compute bytes to the end of the extent, 1503 * possibly including a partial sector at EOF. */ 1504 *pnum = hole - offset; 1505 1506 /* 1507 * We are not allowed to return partial sectors, though, so 1508 * round up if necessary. 1509 */ 1510 if (!QEMU_IS_ALIGNED(*pnum, bs->bl.request_alignment)) { 1511 int64_t file_length = qemu_gluster_co_getlength(bs); 1512 if (file_length > 0) { 1513 /* Ignore errors, this is just a safeguard */ 1514 assert(hole == file_length); 1515 } 1516 *pnum = ROUND_UP(*pnum, bs->bl.request_alignment); 1517 } 1518 1519 ret = BDRV_BLOCK_DATA; 1520 } else { 1521 /* On a hole, compute bytes to the beginning of the next extent. */ 1522 assert(hole == offset); 1523 *pnum = data - offset; 1524 ret = BDRV_BLOCK_ZERO; 1525 } 1526 1527 *map = offset; 1528 *file = bs; 1529 1530 return ret | BDRV_BLOCK_OFFSET_VALID; 1531 } 1532 1533 1534 static const char *const gluster_strong_open_opts[] = { 1535 GLUSTER_OPT_VOLUME, 1536 GLUSTER_OPT_PATH, 1537 GLUSTER_OPT_TYPE, 1538 GLUSTER_OPT_SERVER_PATTERN, 1539 GLUSTER_OPT_HOST, 1540 GLUSTER_OPT_PORT, 1541 GLUSTER_OPT_TO, 1542 GLUSTER_OPT_IPV4, 1543 GLUSTER_OPT_IPV6, 1544 GLUSTER_OPT_SOCKET, 1545 1546 NULL 1547 }; 1548 1549 static BlockDriver bdrv_gluster = { 1550 .format_name = "gluster", 1551 .protocol_name = "gluster", 1552 .instance_size = sizeof(BDRVGlusterState), 1553 .bdrv_open = qemu_gluster_open, 1554 .bdrv_reopen_prepare = qemu_gluster_reopen_prepare, 1555 .bdrv_reopen_commit = qemu_gluster_reopen_commit, 1556 .bdrv_reopen_abort = qemu_gluster_reopen_abort, 1557 .bdrv_close = qemu_gluster_close, 1558 .bdrv_co_create = qemu_gluster_co_create, 1559 .bdrv_co_create_opts = qemu_gluster_co_create_opts, 1560 .bdrv_co_getlength = qemu_gluster_co_getlength, 1561 .bdrv_co_get_allocated_file_size = qemu_gluster_co_get_allocated_file_size, 1562 .bdrv_co_truncate = qemu_gluster_co_truncate, 1563 .bdrv_co_readv = qemu_gluster_co_readv, 1564 .bdrv_co_writev = qemu_gluster_co_writev, 1565 .bdrv_co_flush_to_disk = qemu_gluster_co_flush_to_disk, 1566 #ifdef CONFIG_GLUSTERFS_DISCARD 1567 .bdrv_co_pdiscard = qemu_gluster_co_pdiscard, 1568 #endif 1569 #ifdef CONFIG_GLUSTERFS_ZEROFILL 1570 .bdrv_co_pwrite_zeroes = qemu_gluster_co_pwrite_zeroes, 1571 #endif 1572 .bdrv_co_block_status = qemu_gluster_co_block_status, 1573 .bdrv_refresh_limits = qemu_gluster_refresh_limits, 1574 .create_opts = &qemu_gluster_create_opts, 1575 .strong_runtime_opts = gluster_strong_open_opts, 1576 }; 1577 1578 static BlockDriver bdrv_gluster_tcp = { 1579 .format_name = "gluster", 1580 .protocol_name = "gluster+tcp", 1581 .instance_size = sizeof(BDRVGlusterState), 1582 .bdrv_open = qemu_gluster_open, 1583 .bdrv_reopen_prepare = qemu_gluster_reopen_prepare, 1584 .bdrv_reopen_commit = qemu_gluster_reopen_commit, 1585 .bdrv_reopen_abort = qemu_gluster_reopen_abort, 1586 .bdrv_close = qemu_gluster_close, 1587 .bdrv_co_create = qemu_gluster_co_create, 1588 .bdrv_co_create_opts = qemu_gluster_co_create_opts, 1589 .bdrv_co_getlength = qemu_gluster_co_getlength, 1590 .bdrv_co_get_allocated_file_size = qemu_gluster_co_get_allocated_file_size, 1591 .bdrv_co_truncate = qemu_gluster_co_truncate, 1592 .bdrv_co_readv = qemu_gluster_co_readv, 1593 .bdrv_co_writev = qemu_gluster_co_writev, 1594 .bdrv_co_flush_to_disk = qemu_gluster_co_flush_to_disk, 1595 #ifdef CONFIG_GLUSTERFS_DISCARD 1596 .bdrv_co_pdiscard = qemu_gluster_co_pdiscard, 1597 #endif 1598 #ifdef CONFIG_GLUSTERFS_ZEROFILL 1599 .bdrv_co_pwrite_zeroes = qemu_gluster_co_pwrite_zeroes, 1600 #endif 1601 .bdrv_co_block_status = qemu_gluster_co_block_status, 1602 .bdrv_refresh_limits = qemu_gluster_refresh_limits, 1603 .create_opts = &qemu_gluster_create_opts, 1604 .strong_runtime_opts = gluster_strong_open_opts, 1605 }; 1606 1607 static BlockDriver bdrv_gluster_unix = { 1608 .format_name = "gluster", 1609 .protocol_name = "gluster+unix", 1610 .instance_size = sizeof(BDRVGlusterState), 1611 .bdrv_open = qemu_gluster_open, 1612 .bdrv_reopen_prepare = qemu_gluster_reopen_prepare, 1613 .bdrv_reopen_commit = qemu_gluster_reopen_commit, 1614 .bdrv_reopen_abort = qemu_gluster_reopen_abort, 1615 .bdrv_close = qemu_gluster_close, 1616 .bdrv_co_create = qemu_gluster_co_create, 1617 .bdrv_co_create_opts = qemu_gluster_co_create_opts, 1618 .bdrv_co_getlength = qemu_gluster_co_getlength, 1619 .bdrv_co_get_allocated_file_size = qemu_gluster_co_get_allocated_file_size, 1620 .bdrv_co_truncate = qemu_gluster_co_truncate, 1621 .bdrv_co_readv = qemu_gluster_co_readv, 1622 .bdrv_co_writev = qemu_gluster_co_writev, 1623 .bdrv_co_flush_to_disk = qemu_gluster_co_flush_to_disk, 1624 #ifdef CONFIG_GLUSTERFS_DISCARD 1625 .bdrv_co_pdiscard = qemu_gluster_co_pdiscard, 1626 #endif 1627 #ifdef CONFIG_GLUSTERFS_ZEROFILL 1628 .bdrv_co_pwrite_zeroes = qemu_gluster_co_pwrite_zeroes, 1629 #endif 1630 .bdrv_co_block_status = qemu_gluster_co_block_status, 1631 .bdrv_refresh_limits = qemu_gluster_refresh_limits, 1632 .create_opts = &qemu_gluster_create_opts, 1633 .strong_runtime_opts = gluster_strong_open_opts, 1634 }; 1635 1636 static void bdrv_gluster_init(void) 1637 { 1638 bdrv_register(&bdrv_gluster_unix); 1639 bdrv_register(&bdrv_gluster_tcp); 1640 bdrv_register(&bdrv_gluster); 1641 } 1642 1643 block_init(bdrv_gluster_init); 1644