1 /* 2 * GlusterFS backend for QEMU 3 * 4 * Copyright (C) 2012 Bharata B Rao <bharata@linux.vnet.ibm.com> 5 * 6 * This work is licensed under the terms of the GNU GPL, version 2 or later. 7 * See the COPYING file in the top-level directory. 8 * 9 */ 10 11 #include "qemu/osdep.h" 12 #include "qemu/units.h" 13 #include <glusterfs/api/glfs.h> 14 #include "block/block_int.h" 15 #include "block/qdict.h" 16 #include "qapi/error.h" 17 #include "qapi/qmp/qdict.h" 18 #include "qapi/qmp/qerror.h" 19 #include "qemu/uri.h" 20 #include "qemu/error-report.h" 21 #include "qemu/module.h" 22 #include "qemu/option.h" 23 #include "qemu/cutils.h" 24 25 #ifdef CONFIG_GLUSTERFS_FTRUNCATE_HAS_STAT 26 # define glfs_ftruncate(fd, offset) glfs_ftruncate(fd, offset, NULL, NULL) 27 #endif 28 29 #define GLUSTER_OPT_FILENAME "filename" 30 #define GLUSTER_OPT_VOLUME "volume" 31 #define GLUSTER_OPT_PATH "path" 32 #define GLUSTER_OPT_TYPE "type" 33 #define GLUSTER_OPT_SERVER_PATTERN "server." 34 #define GLUSTER_OPT_HOST "host" 35 #define GLUSTER_OPT_PORT "port" 36 #define GLUSTER_OPT_TO "to" 37 #define GLUSTER_OPT_IPV4 "ipv4" 38 #define GLUSTER_OPT_IPV6 "ipv6" 39 #define GLUSTER_OPT_SOCKET "socket" 40 #define GLUSTER_OPT_DEBUG "debug" 41 #define GLUSTER_DEFAULT_PORT 24007 42 #define GLUSTER_DEBUG_DEFAULT 4 43 #define GLUSTER_DEBUG_MAX 9 44 #define GLUSTER_OPT_LOGFILE "logfile" 45 #define GLUSTER_LOGFILE_DEFAULT "-" /* handled in libgfapi as /dev/stderr */ 46 /* 47 * Several versions of GlusterFS (3.12? -> 6.0.1) fail when the transfer size 48 * is greater or equal to 1024 MiB, so we are limiting the transfer size to 512 49 * MiB to avoid this rare issue. 50 */ 51 #define GLUSTER_MAX_TRANSFER (512 * MiB) 52 53 #define GERR_INDEX_HINT "hint: check in 'server' array index '%d'\n" 54 55 typedef struct GlusterAIOCB { 56 int64_t size; 57 int ret; 58 Coroutine *coroutine; 59 AioContext *aio_context; 60 } GlusterAIOCB; 61 62 typedef struct BDRVGlusterState { 63 struct glfs *glfs; 64 struct glfs_fd *fd; 65 char *logfile; 66 bool supports_seek_data; 67 int debug; 68 } BDRVGlusterState; 69 70 typedef struct BDRVGlusterReopenState { 71 struct glfs *glfs; 72 struct glfs_fd *fd; 73 } BDRVGlusterReopenState; 74 75 76 typedef struct GlfsPreopened { 77 char *volume; 78 glfs_t *fs; 79 int ref; 80 } GlfsPreopened; 81 82 typedef struct ListElement { 83 QLIST_ENTRY(ListElement) list; 84 GlfsPreopened saved; 85 } ListElement; 86 87 static QLIST_HEAD(, ListElement) glfs_list; 88 89 static QemuOptsList qemu_gluster_create_opts = { 90 .name = "qemu-gluster-create-opts", 91 .head = QTAILQ_HEAD_INITIALIZER(qemu_gluster_create_opts.head), 92 .desc = { 93 { 94 .name = BLOCK_OPT_SIZE, 95 .type = QEMU_OPT_SIZE, 96 .help = "Virtual disk size" 97 }, 98 { 99 .name = BLOCK_OPT_PREALLOC, 100 .type = QEMU_OPT_STRING, 101 .help = "Preallocation mode (allowed values: off" 102 #ifdef CONFIG_GLUSTERFS_FALLOCATE 103 ", falloc" 104 #endif 105 #ifdef CONFIG_GLUSTERFS_ZEROFILL 106 ", full" 107 #endif 108 ")" 109 }, 110 { 111 .name = GLUSTER_OPT_DEBUG, 112 .type = QEMU_OPT_NUMBER, 113 .help = "Gluster log level, valid range is 0-9", 114 }, 115 { 116 .name = GLUSTER_OPT_LOGFILE, 117 .type = QEMU_OPT_STRING, 118 .help = "Logfile path of libgfapi", 119 }, 120 { /* end of list */ } 121 } 122 }; 123 124 static QemuOptsList runtime_opts = { 125 .name = "gluster", 126 .head = QTAILQ_HEAD_INITIALIZER(runtime_opts.head), 127 .desc = { 128 { 129 .name = GLUSTER_OPT_FILENAME, 130 .type = QEMU_OPT_STRING, 131 .help = "URL to the gluster image", 132 }, 133 { 134 .name = GLUSTER_OPT_DEBUG, 135 .type = QEMU_OPT_NUMBER, 136 .help = "Gluster log level, valid range is 0-9", 137 }, 138 { 139 .name = GLUSTER_OPT_LOGFILE, 140 .type = QEMU_OPT_STRING, 141 .help = "Logfile path of libgfapi", 142 }, 143 { /* end of list */ } 144 }, 145 }; 146 147 static QemuOptsList runtime_json_opts = { 148 .name = "gluster_json", 149 .head = QTAILQ_HEAD_INITIALIZER(runtime_json_opts.head), 150 .desc = { 151 { 152 .name = GLUSTER_OPT_VOLUME, 153 .type = QEMU_OPT_STRING, 154 .help = "name of gluster volume where VM image resides", 155 }, 156 { 157 .name = GLUSTER_OPT_PATH, 158 .type = QEMU_OPT_STRING, 159 .help = "absolute path to image file in gluster volume", 160 }, 161 { 162 .name = GLUSTER_OPT_DEBUG, 163 .type = QEMU_OPT_NUMBER, 164 .help = "Gluster log level, valid range is 0-9", 165 }, 166 { /* end of list */ } 167 }, 168 }; 169 170 static QemuOptsList runtime_type_opts = { 171 .name = "gluster_type", 172 .head = QTAILQ_HEAD_INITIALIZER(runtime_type_opts.head), 173 .desc = { 174 { 175 .name = GLUSTER_OPT_TYPE, 176 .type = QEMU_OPT_STRING, 177 .help = "inet|unix", 178 }, 179 { /* end of list */ } 180 }, 181 }; 182 183 static QemuOptsList runtime_unix_opts = { 184 .name = "gluster_unix", 185 .head = QTAILQ_HEAD_INITIALIZER(runtime_unix_opts.head), 186 .desc = { 187 { 188 .name = GLUSTER_OPT_SOCKET, 189 .type = QEMU_OPT_STRING, 190 .help = "socket file path (legacy)", 191 }, 192 { 193 .name = GLUSTER_OPT_PATH, 194 .type = QEMU_OPT_STRING, 195 .help = "socket file path (QAPI)", 196 }, 197 { /* end of list */ } 198 }, 199 }; 200 201 static QemuOptsList runtime_inet_opts = { 202 .name = "gluster_inet", 203 .head = QTAILQ_HEAD_INITIALIZER(runtime_inet_opts.head), 204 .desc = { 205 { 206 .name = GLUSTER_OPT_TYPE, 207 .type = QEMU_OPT_STRING, 208 .help = "inet|unix", 209 }, 210 { 211 .name = GLUSTER_OPT_HOST, 212 .type = QEMU_OPT_STRING, 213 .help = "host address (hostname/ipv4/ipv6 addresses)", 214 }, 215 { 216 .name = GLUSTER_OPT_PORT, 217 .type = QEMU_OPT_STRING, 218 .help = "port number on which glusterd is listening (default 24007)", 219 }, 220 { 221 .name = "to", 222 .type = QEMU_OPT_NUMBER, 223 .help = "max port number, not supported by gluster", 224 }, 225 { 226 .name = "ipv4", 227 .type = QEMU_OPT_BOOL, 228 .help = "ipv4 bool value, not supported by gluster", 229 }, 230 { 231 .name = "ipv6", 232 .type = QEMU_OPT_BOOL, 233 .help = "ipv6 bool value, not supported by gluster", 234 }, 235 { /* end of list */ } 236 }, 237 }; 238 239 static void glfs_set_preopened(const char *volume, glfs_t *fs) 240 { 241 ListElement *entry = NULL; 242 243 entry = g_new(ListElement, 1); 244 245 entry->saved.volume = g_strdup(volume); 246 247 entry->saved.fs = fs; 248 entry->saved.ref = 1; 249 250 QLIST_INSERT_HEAD(&glfs_list, entry, list); 251 } 252 253 static glfs_t *glfs_find_preopened(const char *volume) 254 { 255 ListElement *entry = NULL; 256 257 QLIST_FOREACH(entry, &glfs_list, list) { 258 if (strcmp(entry->saved.volume, volume) == 0) { 259 entry->saved.ref++; 260 return entry->saved.fs; 261 } 262 } 263 264 return NULL; 265 } 266 267 static void glfs_clear_preopened(glfs_t *fs) 268 { 269 ListElement *entry = NULL; 270 ListElement *next; 271 272 if (fs == NULL) { 273 return; 274 } 275 276 QLIST_FOREACH_SAFE(entry, &glfs_list, list, next) { 277 if (entry->saved.fs == fs) { 278 if (--entry->saved.ref) { 279 return; 280 } 281 282 QLIST_REMOVE(entry, list); 283 284 glfs_fini(entry->saved.fs); 285 g_free(entry->saved.volume); 286 g_free(entry); 287 } 288 } 289 } 290 291 static int parse_volume_options(BlockdevOptionsGluster *gconf, char *path) 292 { 293 char *p, *q; 294 295 if (!path) { 296 return -EINVAL; 297 } 298 299 /* volume */ 300 p = q = path + strspn(path, "/"); 301 p += strcspn(p, "/"); 302 if (*p == '\0') { 303 return -EINVAL; 304 } 305 gconf->volume = g_strndup(q, p - q); 306 307 /* path */ 308 p += strspn(p, "/"); 309 if (*p == '\0') { 310 return -EINVAL; 311 } 312 gconf->path = g_strdup(p); 313 return 0; 314 } 315 316 /* 317 * file=gluster[+transport]://[host[:port]]/volume/path[?socket=...] 318 * 319 * 'gluster' is the protocol. 320 * 321 * 'transport' specifies the transport type used to connect to gluster 322 * management daemon (glusterd). Valid transport types are 323 * tcp or unix. If a transport type isn't specified, then tcp type is assumed. 324 * 325 * 'host' specifies the host where the volume file specification for 326 * the given volume resides. This can be either hostname or ipv4 address. 327 * If transport type is 'unix', then 'host' field should not be specified. 328 * The 'socket' field needs to be populated with the path to unix domain 329 * socket. 330 * 331 * 'port' is the port number on which glusterd is listening. This is optional 332 * and if not specified, QEMU will send 0 which will make gluster to use the 333 * default port. If the transport type is unix, then 'port' should not be 334 * specified. 335 * 336 * 'volume' is the name of the gluster volume which contains the VM image. 337 * 338 * 'path' is the path to the actual VM image that resides on gluster volume. 339 * 340 * Examples: 341 * 342 * file=gluster://1.2.3.4/testvol/a.img 343 * file=gluster+tcp://1.2.3.4/testvol/a.img 344 * file=gluster+tcp://1.2.3.4:24007/testvol/dir/a.img 345 * file=gluster+tcp://host.domain.com:24007/testvol/dir/a.img 346 * file=gluster+unix:///testvol/dir/a.img?socket=/tmp/glusterd.socket 347 */ 348 static int qemu_gluster_parse_uri(BlockdevOptionsGluster *gconf, 349 const char *filename) 350 { 351 SocketAddress *gsconf; 352 URI *uri; 353 QueryParams *qp = NULL; 354 bool is_unix = false; 355 int ret = 0; 356 357 uri = uri_parse(filename); 358 if (!uri) { 359 return -EINVAL; 360 } 361 362 gsconf = g_new0(SocketAddress, 1); 363 QAPI_LIST_PREPEND(gconf->server, gsconf); 364 365 /* transport */ 366 if (!uri->scheme || !strcmp(uri->scheme, "gluster")) { 367 gsconf->type = SOCKET_ADDRESS_TYPE_INET; 368 } else if (!strcmp(uri->scheme, "gluster+tcp")) { 369 gsconf->type = SOCKET_ADDRESS_TYPE_INET; 370 } else if (!strcmp(uri->scheme, "gluster+unix")) { 371 gsconf->type = SOCKET_ADDRESS_TYPE_UNIX; 372 is_unix = true; 373 } else if (!strcmp(uri->scheme, "gluster+rdma")) { 374 gsconf->type = SOCKET_ADDRESS_TYPE_INET; 375 warn_report("rdma feature is not supported, falling back to tcp"); 376 } else { 377 ret = -EINVAL; 378 goto out; 379 } 380 381 ret = parse_volume_options(gconf, uri->path); 382 if (ret < 0) { 383 goto out; 384 } 385 386 qp = query_params_parse(uri->query); 387 if (qp->n > 1 || (is_unix && !qp->n) || (!is_unix && qp->n)) { 388 ret = -EINVAL; 389 goto out; 390 } 391 392 if (is_unix) { 393 if (uri->server || uri->port) { 394 ret = -EINVAL; 395 goto out; 396 } 397 if (strcmp(qp->p[0].name, "socket")) { 398 ret = -EINVAL; 399 goto out; 400 } 401 gsconf->u.q_unix.path = g_strdup(qp->p[0].value); 402 } else { 403 gsconf->u.inet.host = g_strdup(uri->server ? uri->server : "localhost"); 404 if (uri->port) { 405 gsconf->u.inet.port = g_strdup_printf("%d", uri->port); 406 } else { 407 gsconf->u.inet.port = g_strdup_printf("%d", GLUSTER_DEFAULT_PORT); 408 } 409 } 410 411 out: 412 if (qp) { 413 query_params_free(qp); 414 } 415 uri_free(uri); 416 return ret; 417 } 418 419 static struct glfs *qemu_gluster_glfs_init(BlockdevOptionsGluster *gconf, 420 Error **errp) 421 { 422 struct glfs *glfs; 423 int ret; 424 int old_errno; 425 SocketAddressList *server; 426 unsigned long long port; 427 428 glfs = glfs_find_preopened(gconf->volume); 429 if (glfs) { 430 return glfs; 431 } 432 433 glfs = glfs_new(gconf->volume); 434 if (!glfs) { 435 goto out; 436 } 437 438 glfs_set_preopened(gconf->volume, glfs); 439 440 for (server = gconf->server; server; server = server->next) { 441 switch (server->value->type) { 442 case SOCKET_ADDRESS_TYPE_UNIX: 443 ret = glfs_set_volfile_server(glfs, "unix", 444 server->value->u.q_unix.path, 0); 445 break; 446 case SOCKET_ADDRESS_TYPE_INET: 447 if (parse_uint_full(server->value->u.inet.port, &port, 10) < 0 || 448 port > 65535) { 449 error_setg(errp, "'%s' is not a valid port number", 450 server->value->u.inet.port); 451 errno = EINVAL; 452 goto out; 453 } 454 ret = glfs_set_volfile_server(glfs, "tcp", 455 server->value->u.inet.host, 456 (int)port); 457 break; 458 case SOCKET_ADDRESS_TYPE_VSOCK: 459 case SOCKET_ADDRESS_TYPE_FD: 460 default: 461 abort(); 462 } 463 464 if (ret < 0) { 465 goto out; 466 } 467 } 468 469 ret = glfs_set_logging(glfs, gconf->logfile, gconf->debug); 470 if (ret < 0) { 471 goto out; 472 } 473 474 ret = glfs_init(glfs); 475 if (ret) { 476 error_setg(errp, "Gluster connection for volume %s, path %s failed" 477 " to connect", gconf->volume, gconf->path); 478 for (server = gconf->server; server; server = server->next) { 479 if (server->value->type == SOCKET_ADDRESS_TYPE_UNIX) { 480 error_append_hint(errp, "hint: failed on socket %s ", 481 server->value->u.q_unix.path); 482 } else { 483 error_append_hint(errp, "hint: failed on host %s and port %s ", 484 server->value->u.inet.host, 485 server->value->u.inet.port); 486 } 487 } 488 489 error_append_hint(errp, "Please refer to gluster logs for more info\n"); 490 491 /* glfs_init sometimes doesn't set errno although docs suggest that */ 492 if (errno == 0) { 493 errno = EINVAL; 494 } 495 496 goto out; 497 } 498 return glfs; 499 500 out: 501 if (glfs) { 502 old_errno = errno; 503 glfs_clear_preopened(glfs); 504 errno = old_errno; 505 } 506 return NULL; 507 } 508 509 /* 510 * Convert the json formatted command line into qapi. 511 */ 512 static int qemu_gluster_parse_json(BlockdevOptionsGluster *gconf, 513 QDict *options, Error **errp) 514 { 515 QemuOpts *opts; 516 SocketAddress *gsconf = NULL; 517 SocketAddressList **tail; 518 QDict *backing_options = NULL; 519 Error *local_err = NULL; 520 char *str = NULL; 521 const char *ptr; 522 int i, type, num_servers; 523 524 /* create opts info from runtime_json_opts list */ 525 opts = qemu_opts_create(&runtime_json_opts, NULL, 0, &error_abort); 526 if (!qemu_opts_absorb_qdict(opts, options, errp)) { 527 goto out; 528 } 529 530 num_servers = qdict_array_entries(options, GLUSTER_OPT_SERVER_PATTERN); 531 if (num_servers < 1) { 532 error_setg(&local_err, QERR_MISSING_PARAMETER, "server"); 533 goto out; 534 } 535 536 ptr = qemu_opt_get(opts, GLUSTER_OPT_VOLUME); 537 if (!ptr) { 538 error_setg(&local_err, QERR_MISSING_PARAMETER, GLUSTER_OPT_VOLUME); 539 goto out; 540 } 541 gconf->volume = g_strdup(ptr); 542 543 ptr = qemu_opt_get(opts, GLUSTER_OPT_PATH); 544 if (!ptr) { 545 error_setg(&local_err, QERR_MISSING_PARAMETER, GLUSTER_OPT_PATH); 546 goto out; 547 } 548 gconf->path = g_strdup(ptr); 549 qemu_opts_del(opts); 550 tail = &gconf->server; 551 552 for (i = 0; i < num_servers; i++) { 553 str = g_strdup_printf(GLUSTER_OPT_SERVER_PATTERN"%d.", i); 554 qdict_extract_subqdict(options, &backing_options, str); 555 556 /* create opts info from runtime_type_opts list */ 557 opts = qemu_opts_create(&runtime_type_opts, NULL, 0, &error_abort); 558 if (!qemu_opts_absorb_qdict(opts, backing_options, errp)) { 559 goto out; 560 } 561 562 ptr = qemu_opt_get(opts, GLUSTER_OPT_TYPE); 563 if (!ptr) { 564 error_setg(&local_err, QERR_MISSING_PARAMETER, GLUSTER_OPT_TYPE); 565 error_append_hint(&local_err, GERR_INDEX_HINT, i); 566 goto out; 567 568 } 569 gsconf = g_new0(SocketAddress, 1); 570 if (!strcmp(ptr, "tcp")) { 571 ptr = "inet"; /* accept legacy "tcp" */ 572 } 573 type = qapi_enum_parse(&SocketAddressType_lookup, ptr, -1, NULL); 574 if (type != SOCKET_ADDRESS_TYPE_INET 575 && type != SOCKET_ADDRESS_TYPE_UNIX) { 576 error_setg(&local_err, 577 "Parameter '%s' may be 'inet' or 'unix'", 578 GLUSTER_OPT_TYPE); 579 error_append_hint(&local_err, GERR_INDEX_HINT, i); 580 goto out; 581 } 582 gsconf->type = type; 583 qemu_opts_del(opts); 584 585 if (gsconf->type == SOCKET_ADDRESS_TYPE_INET) { 586 /* create opts info from runtime_inet_opts list */ 587 opts = qemu_opts_create(&runtime_inet_opts, NULL, 0, &error_abort); 588 if (!qemu_opts_absorb_qdict(opts, backing_options, errp)) { 589 goto out; 590 } 591 592 ptr = qemu_opt_get(opts, GLUSTER_OPT_HOST); 593 if (!ptr) { 594 error_setg(&local_err, QERR_MISSING_PARAMETER, 595 GLUSTER_OPT_HOST); 596 error_append_hint(&local_err, GERR_INDEX_HINT, i); 597 goto out; 598 } 599 gsconf->u.inet.host = g_strdup(ptr); 600 ptr = qemu_opt_get(opts, GLUSTER_OPT_PORT); 601 if (!ptr) { 602 error_setg(&local_err, QERR_MISSING_PARAMETER, 603 GLUSTER_OPT_PORT); 604 error_append_hint(&local_err, GERR_INDEX_HINT, i); 605 goto out; 606 } 607 gsconf->u.inet.port = g_strdup(ptr); 608 609 /* defend for unsupported fields in InetSocketAddress, 610 * i.e. @ipv4, @ipv6 and @to 611 */ 612 ptr = qemu_opt_get(opts, GLUSTER_OPT_TO); 613 if (ptr) { 614 gsconf->u.inet.has_to = true; 615 } 616 ptr = qemu_opt_get(opts, GLUSTER_OPT_IPV4); 617 if (ptr) { 618 gsconf->u.inet.has_ipv4 = true; 619 } 620 ptr = qemu_opt_get(opts, GLUSTER_OPT_IPV6); 621 if (ptr) { 622 gsconf->u.inet.has_ipv6 = true; 623 } 624 if (gsconf->u.inet.has_to) { 625 error_setg(&local_err, "Parameter 'to' not supported"); 626 goto out; 627 } 628 if (gsconf->u.inet.has_ipv4 || gsconf->u.inet.has_ipv6) { 629 error_setg(&local_err, "Parameters 'ipv4/ipv6' not supported"); 630 goto out; 631 } 632 qemu_opts_del(opts); 633 } else { 634 /* create opts info from runtime_unix_opts list */ 635 opts = qemu_opts_create(&runtime_unix_opts, NULL, 0, &error_abort); 636 if (!qemu_opts_absorb_qdict(opts, backing_options, errp)) { 637 goto out; 638 } 639 640 ptr = qemu_opt_get(opts, GLUSTER_OPT_PATH); 641 if (!ptr) { 642 ptr = qemu_opt_get(opts, GLUSTER_OPT_SOCKET); 643 } else if (qemu_opt_get(opts, GLUSTER_OPT_SOCKET)) { 644 error_setg(&local_err, 645 "Conflicting parameters 'path' and 'socket'"); 646 error_append_hint(&local_err, GERR_INDEX_HINT, i); 647 goto out; 648 } 649 if (!ptr) { 650 error_setg(&local_err, QERR_MISSING_PARAMETER, 651 GLUSTER_OPT_PATH); 652 error_append_hint(&local_err, GERR_INDEX_HINT, i); 653 goto out; 654 } 655 gsconf->u.q_unix.path = g_strdup(ptr); 656 qemu_opts_del(opts); 657 } 658 659 QAPI_LIST_APPEND(tail, gsconf); 660 gsconf = NULL; 661 662 qobject_unref(backing_options); 663 backing_options = NULL; 664 g_free(str); 665 str = NULL; 666 } 667 668 return 0; 669 670 out: 671 error_propagate(errp, local_err); 672 qapi_free_SocketAddress(gsconf); 673 qemu_opts_del(opts); 674 g_free(str); 675 qobject_unref(backing_options); 676 errno = EINVAL; 677 return -errno; 678 } 679 680 /* Converts options given in @filename and the @options QDict into the QAPI 681 * object @gconf. */ 682 static int qemu_gluster_parse(BlockdevOptionsGluster *gconf, 683 const char *filename, 684 QDict *options, Error **errp) 685 { 686 int ret; 687 if (filename) { 688 ret = qemu_gluster_parse_uri(gconf, filename); 689 if (ret < 0) { 690 error_setg(errp, "invalid URI %s", filename); 691 error_append_hint(errp, "Usage: file=gluster[+transport]://" 692 "[host[:port]]volume/path[?socket=...]" 693 "[,file.debug=N]" 694 "[,file.logfile=/path/filename.log]\n"); 695 return ret; 696 } 697 } else { 698 ret = qemu_gluster_parse_json(gconf, options, errp); 699 if (ret < 0) { 700 error_append_hint(errp, "Usage: " 701 "-drive driver=qcow2,file.driver=gluster," 702 "file.volume=testvol,file.path=/path/a.qcow2" 703 "[,file.debug=9]" 704 "[,file.logfile=/path/filename.log]," 705 "file.server.0.type=inet," 706 "file.server.0.host=1.2.3.4," 707 "file.server.0.port=24007," 708 "file.server.1.transport=unix," 709 "file.server.1.path=/var/run/glusterd.socket ..." 710 "\n"); 711 return ret; 712 } 713 } 714 715 return 0; 716 } 717 718 static struct glfs *qemu_gluster_init(BlockdevOptionsGluster *gconf, 719 const char *filename, 720 QDict *options, Error **errp) 721 { 722 int ret; 723 724 ret = qemu_gluster_parse(gconf, filename, options, errp); 725 if (ret < 0) { 726 errno = -ret; 727 return NULL; 728 } 729 730 return qemu_gluster_glfs_init(gconf, errp); 731 } 732 733 /* 734 * AIO callback routine called from GlusterFS thread. 735 */ 736 static void gluster_finish_aiocb(struct glfs_fd *fd, ssize_t ret, 737 #ifdef CONFIG_GLUSTERFS_IOCB_HAS_STAT 738 struct glfs_stat *pre, struct glfs_stat *post, 739 #endif 740 void *arg) 741 { 742 GlusterAIOCB *acb = (GlusterAIOCB *)arg; 743 744 if (!ret || ret == acb->size) { 745 acb->ret = 0; /* Success */ 746 } else if (ret < 0) { 747 acb->ret = -errno; /* Read/Write failed */ 748 } else { 749 acb->ret = -EIO; /* Partial read/write - fail it */ 750 } 751 752 aio_co_schedule(acb->aio_context, acb->coroutine); 753 } 754 755 static void qemu_gluster_parse_flags(int bdrv_flags, int *open_flags) 756 { 757 assert(open_flags != NULL); 758 759 *open_flags |= O_BINARY; 760 761 if (bdrv_flags & BDRV_O_RDWR) { 762 *open_flags |= O_RDWR; 763 } else { 764 *open_flags |= O_RDONLY; 765 } 766 767 if ((bdrv_flags & BDRV_O_NOCACHE)) { 768 *open_flags |= O_DIRECT; 769 } 770 } 771 772 /* 773 * Do SEEK_DATA/HOLE to detect if it is functional. Older broken versions of 774 * gfapi incorrectly return the current offset when SEEK_DATA/HOLE is used. 775 * - Corrected versions return -1 and set errno to EINVAL. 776 * - Versions that support SEEK_DATA/HOLE correctly, will return -1 and set 777 * errno to ENXIO when SEEK_DATA is called with a position of EOF. 778 */ 779 static bool qemu_gluster_test_seek(struct glfs_fd *fd) 780 { 781 off_t ret = 0; 782 783 #if defined SEEK_HOLE && defined SEEK_DATA 784 off_t eof; 785 786 eof = glfs_lseek(fd, 0, SEEK_END); 787 if (eof < 0) { 788 /* this should never occur */ 789 return false; 790 } 791 792 /* this should always fail with ENXIO if SEEK_DATA is supported */ 793 ret = glfs_lseek(fd, eof, SEEK_DATA); 794 #endif 795 796 return (ret < 0) && (errno == ENXIO); 797 } 798 799 static int qemu_gluster_open(BlockDriverState *bs, QDict *options, 800 int bdrv_flags, Error **errp) 801 { 802 BDRVGlusterState *s = bs->opaque; 803 int open_flags = 0; 804 int ret = 0; 805 BlockdevOptionsGluster *gconf = NULL; 806 QemuOpts *opts; 807 const char *filename, *logfile; 808 809 opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort); 810 if (!qemu_opts_absorb_qdict(opts, options, errp)) { 811 ret = -EINVAL; 812 goto out; 813 } 814 815 filename = qemu_opt_get(opts, GLUSTER_OPT_FILENAME); 816 817 s->debug = qemu_opt_get_number(opts, GLUSTER_OPT_DEBUG, 818 GLUSTER_DEBUG_DEFAULT); 819 if (s->debug < 0) { 820 s->debug = 0; 821 } else if (s->debug > GLUSTER_DEBUG_MAX) { 822 s->debug = GLUSTER_DEBUG_MAX; 823 } 824 825 gconf = g_new0(BlockdevOptionsGluster, 1); 826 gconf->debug = s->debug; 827 gconf->has_debug = true; 828 829 logfile = qemu_opt_get(opts, GLUSTER_OPT_LOGFILE); 830 s->logfile = g_strdup(logfile ? logfile : GLUSTER_LOGFILE_DEFAULT); 831 832 gconf->logfile = g_strdup(s->logfile); 833 gconf->has_logfile = true; 834 835 s->glfs = qemu_gluster_init(gconf, filename, options, errp); 836 if (!s->glfs) { 837 ret = -errno; 838 goto out; 839 } 840 841 #ifdef CONFIG_GLUSTERFS_XLATOR_OPT 842 /* Without this, if fsync fails for a recoverable reason (for instance, 843 * ENOSPC), gluster will dump its cache, preventing retries. This means 844 * almost certain data loss. Not all gluster versions support the 845 * 'resync-failed-syncs-after-fsync' key value, but there is no way to 846 * discover during runtime if it is supported (this api returns success for 847 * unknown key/value pairs) */ 848 ret = glfs_set_xlator_option(s->glfs, "*-write-behind", 849 "resync-failed-syncs-after-fsync", 850 "on"); 851 if (ret < 0) { 852 error_setg_errno(errp, errno, "Unable to set xlator key/value pair"); 853 ret = -errno; 854 goto out; 855 } 856 #endif 857 858 qemu_gluster_parse_flags(bdrv_flags, &open_flags); 859 860 s->fd = glfs_open(s->glfs, gconf->path, open_flags); 861 ret = s->fd ? 0 : -errno; 862 863 if (ret == -EACCES || ret == -EROFS) { 864 /* Try to degrade to read-only, but if it doesn't work, still use the 865 * normal error message. */ 866 if (bdrv_apply_auto_read_only(bs, NULL, NULL) == 0) { 867 open_flags = (open_flags & ~O_RDWR) | O_RDONLY; 868 s->fd = glfs_open(s->glfs, gconf->path, open_flags); 869 ret = s->fd ? 0 : -errno; 870 } 871 } 872 873 s->supports_seek_data = qemu_gluster_test_seek(s->fd); 874 875 out: 876 qemu_opts_del(opts); 877 qapi_free_BlockdevOptionsGluster(gconf); 878 if (!ret) { 879 return ret; 880 } 881 g_free(s->logfile); 882 if (s->fd) { 883 glfs_close(s->fd); 884 } 885 886 glfs_clear_preopened(s->glfs); 887 888 return ret; 889 } 890 891 static void qemu_gluster_refresh_limits(BlockDriverState *bs, Error **errp) 892 { 893 bs->bl.max_transfer = GLUSTER_MAX_TRANSFER; 894 } 895 896 static int qemu_gluster_reopen_prepare(BDRVReopenState *state, 897 BlockReopenQueue *queue, Error **errp) 898 { 899 int ret = 0; 900 BDRVGlusterState *s; 901 BDRVGlusterReopenState *reop_s; 902 BlockdevOptionsGluster *gconf; 903 int open_flags = 0; 904 905 assert(state != NULL); 906 assert(state->bs != NULL); 907 908 s = state->bs->opaque; 909 910 state->opaque = g_new0(BDRVGlusterReopenState, 1); 911 reop_s = state->opaque; 912 913 qemu_gluster_parse_flags(state->flags, &open_flags); 914 915 gconf = g_new0(BlockdevOptionsGluster, 1); 916 gconf->debug = s->debug; 917 gconf->has_debug = true; 918 gconf->logfile = g_strdup(s->logfile); 919 gconf->has_logfile = true; 920 921 /* 922 * If 'state->bs->exact_filename' is empty, 'state->options' should contain 923 * the JSON parameters already parsed. 924 */ 925 if (state->bs->exact_filename[0] != '\0') { 926 reop_s->glfs = qemu_gluster_init(gconf, state->bs->exact_filename, NULL, 927 errp); 928 } else { 929 reop_s->glfs = qemu_gluster_init(gconf, NULL, state->options, errp); 930 } 931 if (reop_s->glfs == NULL) { 932 ret = -errno; 933 goto exit; 934 } 935 936 #ifdef CONFIG_GLUSTERFS_XLATOR_OPT 937 ret = glfs_set_xlator_option(reop_s->glfs, "*-write-behind", 938 "resync-failed-syncs-after-fsync", "on"); 939 if (ret < 0) { 940 error_setg_errno(errp, errno, "Unable to set xlator key/value pair"); 941 ret = -errno; 942 goto exit; 943 } 944 #endif 945 946 reop_s->fd = glfs_open(reop_s->glfs, gconf->path, open_flags); 947 if (reop_s->fd == NULL) { 948 /* reops->glfs will be cleaned up in _abort */ 949 ret = -errno; 950 goto exit; 951 } 952 953 exit: 954 /* state->opaque will be freed in either the _abort or _commit */ 955 qapi_free_BlockdevOptionsGluster(gconf); 956 return ret; 957 } 958 959 static void qemu_gluster_reopen_commit(BDRVReopenState *state) 960 { 961 BDRVGlusterReopenState *reop_s = state->opaque; 962 BDRVGlusterState *s = state->bs->opaque; 963 964 965 /* close the old */ 966 if (s->fd) { 967 glfs_close(s->fd); 968 } 969 970 glfs_clear_preopened(s->glfs); 971 972 /* use the newly opened image / connection */ 973 s->fd = reop_s->fd; 974 s->glfs = reop_s->glfs; 975 976 g_free(state->opaque); 977 state->opaque = NULL; 978 979 return; 980 } 981 982 983 static void qemu_gluster_reopen_abort(BDRVReopenState *state) 984 { 985 BDRVGlusterReopenState *reop_s = state->opaque; 986 987 if (reop_s == NULL) { 988 return; 989 } 990 991 if (reop_s->fd) { 992 glfs_close(reop_s->fd); 993 } 994 995 glfs_clear_preopened(reop_s->glfs); 996 997 g_free(state->opaque); 998 state->opaque = NULL; 999 1000 return; 1001 } 1002 1003 #ifdef CONFIG_GLUSTERFS_ZEROFILL 1004 static coroutine_fn int qemu_gluster_co_pwrite_zeroes(BlockDriverState *bs, 1005 int64_t offset, 1006 int size, 1007 BdrvRequestFlags flags) 1008 { 1009 int ret; 1010 GlusterAIOCB acb; 1011 BDRVGlusterState *s = bs->opaque; 1012 1013 acb.size = size; 1014 acb.ret = 0; 1015 acb.coroutine = qemu_coroutine_self(); 1016 acb.aio_context = bdrv_get_aio_context(bs); 1017 1018 ret = glfs_zerofill_async(s->fd, offset, size, gluster_finish_aiocb, &acb); 1019 if (ret < 0) { 1020 return -errno; 1021 } 1022 1023 qemu_coroutine_yield(); 1024 return acb.ret; 1025 } 1026 #endif 1027 1028 static int qemu_gluster_do_truncate(struct glfs_fd *fd, int64_t offset, 1029 PreallocMode prealloc, Error **errp) 1030 { 1031 int64_t current_length; 1032 1033 current_length = glfs_lseek(fd, 0, SEEK_END); 1034 if (current_length < 0) { 1035 error_setg_errno(errp, errno, "Failed to determine current size"); 1036 return -errno; 1037 } 1038 1039 if (current_length > offset && prealloc != PREALLOC_MODE_OFF) { 1040 error_setg(errp, "Cannot use preallocation for shrinking files"); 1041 return -ENOTSUP; 1042 } 1043 1044 if (current_length == offset) { 1045 return 0; 1046 } 1047 1048 switch (prealloc) { 1049 #ifdef CONFIG_GLUSTERFS_FALLOCATE 1050 case PREALLOC_MODE_FALLOC: 1051 if (glfs_fallocate(fd, 0, current_length, offset - current_length)) { 1052 error_setg_errno(errp, errno, "Could not preallocate data"); 1053 return -errno; 1054 } 1055 break; 1056 #endif /* CONFIG_GLUSTERFS_FALLOCATE */ 1057 #ifdef CONFIG_GLUSTERFS_ZEROFILL 1058 case PREALLOC_MODE_FULL: 1059 if (glfs_ftruncate(fd, offset)) { 1060 error_setg_errno(errp, errno, "Could not resize file"); 1061 return -errno; 1062 } 1063 if (glfs_zerofill(fd, current_length, offset - current_length)) { 1064 error_setg_errno(errp, errno, "Could not zerofill the new area"); 1065 return -errno; 1066 } 1067 break; 1068 #endif /* CONFIG_GLUSTERFS_ZEROFILL */ 1069 case PREALLOC_MODE_OFF: 1070 if (glfs_ftruncate(fd, offset)) { 1071 error_setg_errno(errp, errno, "Could not resize file"); 1072 return -errno; 1073 } 1074 break; 1075 default: 1076 error_setg(errp, "Unsupported preallocation mode: %s", 1077 PreallocMode_str(prealloc)); 1078 return -EINVAL; 1079 } 1080 1081 return 0; 1082 } 1083 1084 static int qemu_gluster_co_create(BlockdevCreateOptions *options, 1085 Error **errp) 1086 { 1087 BlockdevCreateOptionsGluster *opts = &options->u.gluster; 1088 struct glfs *glfs; 1089 struct glfs_fd *fd = NULL; 1090 int ret = 0; 1091 1092 assert(options->driver == BLOCKDEV_DRIVER_GLUSTER); 1093 1094 glfs = qemu_gluster_glfs_init(opts->location, errp); 1095 if (!glfs) { 1096 ret = -errno; 1097 goto out; 1098 } 1099 1100 fd = glfs_creat(glfs, opts->location->path, 1101 O_WRONLY | O_CREAT | O_TRUNC | O_BINARY, S_IRUSR | S_IWUSR); 1102 if (!fd) { 1103 ret = -errno; 1104 goto out; 1105 } 1106 1107 ret = qemu_gluster_do_truncate(fd, opts->size, opts->preallocation, errp); 1108 1109 out: 1110 if (fd) { 1111 if (glfs_close(fd) != 0 && ret == 0) { 1112 ret = -errno; 1113 } 1114 } 1115 glfs_clear_preopened(glfs); 1116 return ret; 1117 } 1118 1119 static int coroutine_fn qemu_gluster_co_create_opts(BlockDriver *drv, 1120 const char *filename, 1121 QemuOpts *opts, 1122 Error **errp) 1123 { 1124 BlockdevCreateOptions *options; 1125 BlockdevCreateOptionsGluster *gopts; 1126 BlockdevOptionsGluster *gconf; 1127 char *tmp = NULL; 1128 Error *local_err = NULL; 1129 int ret; 1130 1131 options = g_new0(BlockdevCreateOptions, 1); 1132 options->driver = BLOCKDEV_DRIVER_GLUSTER; 1133 gopts = &options->u.gluster; 1134 1135 gconf = g_new0(BlockdevOptionsGluster, 1); 1136 gopts->location = gconf; 1137 1138 gopts->size = ROUND_UP(qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0), 1139 BDRV_SECTOR_SIZE); 1140 1141 tmp = qemu_opt_get_del(opts, BLOCK_OPT_PREALLOC); 1142 gopts->preallocation = qapi_enum_parse(&PreallocMode_lookup, tmp, 1143 PREALLOC_MODE_OFF, &local_err); 1144 g_free(tmp); 1145 if (local_err) { 1146 error_propagate(errp, local_err); 1147 ret = -EINVAL; 1148 goto fail; 1149 } 1150 1151 gconf->debug = qemu_opt_get_number_del(opts, GLUSTER_OPT_DEBUG, 1152 GLUSTER_DEBUG_DEFAULT); 1153 if (gconf->debug < 0) { 1154 gconf->debug = 0; 1155 } else if (gconf->debug > GLUSTER_DEBUG_MAX) { 1156 gconf->debug = GLUSTER_DEBUG_MAX; 1157 } 1158 gconf->has_debug = true; 1159 1160 gconf->logfile = qemu_opt_get_del(opts, GLUSTER_OPT_LOGFILE); 1161 if (!gconf->logfile) { 1162 gconf->logfile = g_strdup(GLUSTER_LOGFILE_DEFAULT); 1163 } 1164 gconf->has_logfile = true; 1165 1166 ret = qemu_gluster_parse(gconf, filename, NULL, errp); 1167 if (ret < 0) { 1168 goto fail; 1169 } 1170 1171 ret = qemu_gluster_co_create(options, errp); 1172 if (ret < 0) { 1173 goto fail; 1174 } 1175 1176 ret = 0; 1177 fail: 1178 qapi_free_BlockdevCreateOptions(options); 1179 return ret; 1180 } 1181 1182 static coroutine_fn int qemu_gluster_co_rw(BlockDriverState *bs, 1183 int64_t sector_num, int nb_sectors, 1184 QEMUIOVector *qiov, int write) 1185 { 1186 int ret; 1187 GlusterAIOCB acb; 1188 BDRVGlusterState *s = bs->opaque; 1189 size_t size = nb_sectors * BDRV_SECTOR_SIZE; 1190 off_t offset = sector_num * BDRV_SECTOR_SIZE; 1191 1192 acb.size = size; 1193 acb.ret = 0; 1194 acb.coroutine = qemu_coroutine_self(); 1195 acb.aio_context = bdrv_get_aio_context(bs); 1196 1197 if (write) { 1198 ret = glfs_pwritev_async(s->fd, qiov->iov, qiov->niov, offset, 0, 1199 gluster_finish_aiocb, &acb); 1200 } else { 1201 ret = glfs_preadv_async(s->fd, qiov->iov, qiov->niov, offset, 0, 1202 gluster_finish_aiocb, &acb); 1203 } 1204 1205 if (ret < 0) { 1206 return -errno; 1207 } 1208 1209 qemu_coroutine_yield(); 1210 return acb.ret; 1211 } 1212 1213 static coroutine_fn int qemu_gluster_co_truncate(BlockDriverState *bs, 1214 int64_t offset, 1215 bool exact, 1216 PreallocMode prealloc, 1217 BdrvRequestFlags flags, 1218 Error **errp) 1219 { 1220 BDRVGlusterState *s = bs->opaque; 1221 return qemu_gluster_do_truncate(s->fd, offset, prealloc, errp); 1222 } 1223 1224 static coroutine_fn int qemu_gluster_co_readv(BlockDriverState *bs, 1225 int64_t sector_num, 1226 int nb_sectors, 1227 QEMUIOVector *qiov) 1228 { 1229 return qemu_gluster_co_rw(bs, sector_num, nb_sectors, qiov, 0); 1230 } 1231 1232 static coroutine_fn int qemu_gluster_co_writev(BlockDriverState *bs, 1233 int64_t sector_num, 1234 int nb_sectors, 1235 QEMUIOVector *qiov, 1236 int flags) 1237 { 1238 assert(!flags); 1239 return qemu_gluster_co_rw(bs, sector_num, nb_sectors, qiov, 1); 1240 } 1241 1242 static void qemu_gluster_close(BlockDriverState *bs) 1243 { 1244 BDRVGlusterState *s = bs->opaque; 1245 1246 g_free(s->logfile); 1247 if (s->fd) { 1248 glfs_close(s->fd); 1249 s->fd = NULL; 1250 } 1251 glfs_clear_preopened(s->glfs); 1252 } 1253 1254 static coroutine_fn int qemu_gluster_co_flush_to_disk(BlockDriverState *bs) 1255 { 1256 int ret; 1257 GlusterAIOCB acb; 1258 BDRVGlusterState *s = bs->opaque; 1259 1260 acb.size = 0; 1261 acb.ret = 0; 1262 acb.coroutine = qemu_coroutine_self(); 1263 acb.aio_context = bdrv_get_aio_context(bs); 1264 1265 ret = glfs_fsync_async(s->fd, gluster_finish_aiocb, &acb); 1266 if (ret < 0) { 1267 ret = -errno; 1268 goto error; 1269 } 1270 1271 qemu_coroutine_yield(); 1272 if (acb.ret < 0) { 1273 ret = acb.ret; 1274 goto error; 1275 } 1276 1277 return acb.ret; 1278 1279 error: 1280 /* Some versions of Gluster (3.5.6 -> 3.5.8?) will not retain its cache 1281 * after a fsync failure, so we have no way of allowing the guest to safely 1282 * continue. Gluster versions prior to 3.5.6 don't retain the cache 1283 * either, but will invalidate the fd on error, so this is again our only 1284 * option. 1285 * 1286 * The 'resync-failed-syncs-after-fsync' xlator option for the 1287 * write-behind cache will cause later gluster versions to retain its 1288 * cache after error, so long as the fd remains open. However, we 1289 * currently have no way of knowing if this option is supported. 1290 * 1291 * TODO: Once gluster provides a way for us to determine if the option 1292 * is supported, bypass the closure and setting drv to NULL. */ 1293 qemu_gluster_close(bs); 1294 bs->drv = NULL; 1295 return ret; 1296 } 1297 1298 #ifdef CONFIG_GLUSTERFS_DISCARD 1299 static coroutine_fn int qemu_gluster_co_pdiscard(BlockDriverState *bs, 1300 int64_t offset, int size) 1301 { 1302 int ret; 1303 GlusterAIOCB acb; 1304 BDRVGlusterState *s = bs->opaque; 1305 1306 acb.size = 0; 1307 acb.ret = 0; 1308 acb.coroutine = qemu_coroutine_self(); 1309 acb.aio_context = bdrv_get_aio_context(bs); 1310 1311 ret = glfs_discard_async(s->fd, offset, size, gluster_finish_aiocb, &acb); 1312 if (ret < 0) { 1313 return -errno; 1314 } 1315 1316 qemu_coroutine_yield(); 1317 return acb.ret; 1318 } 1319 #endif 1320 1321 static int64_t qemu_gluster_getlength(BlockDriverState *bs) 1322 { 1323 BDRVGlusterState *s = bs->opaque; 1324 int64_t ret; 1325 1326 ret = glfs_lseek(s->fd, 0, SEEK_END); 1327 if (ret < 0) { 1328 return -errno; 1329 } else { 1330 return ret; 1331 } 1332 } 1333 1334 static int64_t qemu_gluster_allocated_file_size(BlockDriverState *bs) 1335 { 1336 BDRVGlusterState *s = bs->opaque; 1337 struct stat st; 1338 int ret; 1339 1340 ret = glfs_fstat(s->fd, &st); 1341 if (ret < 0) { 1342 return -errno; 1343 } else { 1344 return st.st_blocks * 512; 1345 } 1346 } 1347 1348 /* 1349 * Find allocation range in @bs around offset @start. 1350 * May change underlying file descriptor's file offset. 1351 * If @start is not in a hole, store @start in @data, and the 1352 * beginning of the next hole in @hole, and return 0. 1353 * If @start is in a non-trailing hole, store @start in @hole and the 1354 * beginning of the next non-hole in @data, and return 0. 1355 * If @start is in a trailing hole or beyond EOF, return -ENXIO. 1356 * If we can't find out, return a negative errno other than -ENXIO. 1357 * 1358 * (Shamefully copied from file-posix.c, only minuscule adaptions.) 1359 */ 1360 static int find_allocation(BlockDriverState *bs, off_t start, 1361 off_t *data, off_t *hole) 1362 { 1363 BDRVGlusterState *s = bs->opaque; 1364 1365 if (!s->supports_seek_data) { 1366 goto exit; 1367 } 1368 1369 #if defined SEEK_HOLE && defined SEEK_DATA 1370 off_t offs; 1371 1372 /* 1373 * SEEK_DATA cases: 1374 * D1. offs == start: start is in data 1375 * D2. offs > start: start is in a hole, next data at offs 1376 * D3. offs < 0, errno = ENXIO: either start is in a trailing hole 1377 * or start is beyond EOF 1378 * If the latter happens, the file has been truncated behind 1379 * our back since we opened it. All bets are off then. 1380 * Treating like a trailing hole is simplest. 1381 * D4. offs < 0, errno != ENXIO: we learned nothing 1382 */ 1383 offs = glfs_lseek(s->fd, start, SEEK_DATA); 1384 if (offs < 0) { 1385 return -errno; /* D3 or D4 */ 1386 } 1387 1388 if (offs < start) { 1389 /* This is not a valid return by lseek(). We are safe to just return 1390 * -EIO in this case, and we'll treat it like D4. Unfortunately some 1391 * versions of gluster server will return offs < start, so an assert 1392 * here will unnecessarily abort QEMU. */ 1393 return -EIO; 1394 } 1395 1396 if (offs > start) { 1397 /* D2: in hole, next data at offs */ 1398 *hole = start; 1399 *data = offs; 1400 return 0; 1401 } 1402 1403 /* D1: in data, end not yet known */ 1404 1405 /* 1406 * SEEK_HOLE cases: 1407 * H1. offs == start: start is in a hole 1408 * If this happens here, a hole has been dug behind our back 1409 * since the previous lseek(). 1410 * H2. offs > start: either start is in data, next hole at offs, 1411 * or start is in trailing hole, EOF at offs 1412 * Linux treats trailing holes like any other hole: offs == 1413 * start. Solaris seeks to EOF instead: offs > start (blech). 1414 * If that happens here, a hole has been dug behind our back 1415 * since the previous lseek(). 1416 * H3. offs < 0, errno = ENXIO: start is beyond EOF 1417 * If this happens, the file has been truncated behind our 1418 * back since we opened it. Treat it like a trailing hole. 1419 * H4. offs < 0, errno != ENXIO: we learned nothing 1420 * Pretend we know nothing at all, i.e. "forget" about D1. 1421 */ 1422 offs = glfs_lseek(s->fd, start, SEEK_HOLE); 1423 if (offs < 0) { 1424 return -errno; /* D1 and (H3 or H4) */ 1425 } 1426 1427 if (offs < start) { 1428 /* This is not a valid return by lseek(). We are safe to just return 1429 * -EIO in this case, and we'll treat it like H4. Unfortunately some 1430 * versions of gluster server will return offs < start, so an assert 1431 * here will unnecessarily abort QEMU. */ 1432 return -EIO; 1433 } 1434 1435 if (offs > start) { 1436 /* 1437 * D1 and H2: either in data, next hole at offs, or it was in 1438 * data but is now in a trailing hole. In the latter case, 1439 * all bets are off. Treating it as if it there was data all 1440 * the way to EOF is safe, so simply do that. 1441 */ 1442 *data = start; 1443 *hole = offs; 1444 return 0; 1445 } 1446 1447 /* D1 and H1 */ 1448 return -EBUSY; 1449 #endif 1450 1451 exit: 1452 return -ENOTSUP; 1453 } 1454 1455 /* 1456 * Returns the allocation status of the specified offset. 1457 * 1458 * The block layer guarantees 'offset' and 'bytes' are within bounds. 1459 * 1460 * 'pnum' is set to the number of bytes (including and immediately following 1461 * the specified offset) that are known to be in the same 1462 * allocated/unallocated state. 1463 * 1464 * 'bytes' is a soft cap for 'pnum'. If the information is free, 'pnum' may 1465 * well exceed it. 1466 * 1467 * (Based on raw_co_block_status() from file-posix.c.) 1468 */ 1469 static int coroutine_fn qemu_gluster_co_block_status(BlockDriverState *bs, 1470 bool want_zero, 1471 int64_t offset, 1472 int64_t bytes, 1473 int64_t *pnum, 1474 int64_t *map, 1475 BlockDriverState **file) 1476 { 1477 BDRVGlusterState *s = bs->opaque; 1478 off_t data = 0, hole = 0; 1479 int ret = -EINVAL; 1480 1481 assert(QEMU_IS_ALIGNED(offset | bytes, bs->bl.request_alignment)); 1482 1483 if (!s->fd) { 1484 return ret; 1485 } 1486 1487 if (!want_zero) { 1488 *pnum = bytes; 1489 *map = offset; 1490 *file = bs; 1491 return BDRV_BLOCK_DATA | BDRV_BLOCK_OFFSET_VALID; 1492 } 1493 1494 ret = find_allocation(bs, offset, &data, &hole); 1495 if (ret == -ENXIO) { 1496 /* Trailing hole */ 1497 *pnum = bytes; 1498 ret = BDRV_BLOCK_ZERO; 1499 } else if (ret < 0) { 1500 /* No info available, so pretend there are no holes */ 1501 *pnum = bytes; 1502 ret = BDRV_BLOCK_DATA; 1503 } else if (data == offset) { 1504 /* On a data extent, compute bytes to the end of the extent, 1505 * possibly including a partial sector at EOF. */ 1506 *pnum = hole - offset; 1507 1508 /* 1509 * We are not allowed to return partial sectors, though, so 1510 * round up if necessary. 1511 */ 1512 if (!QEMU_IS_ALIGNED(*pnum, bs->bl.request_alignment)) { 1513 int64_t file_length = qemu_gluster_getlength(bs); 1514 if (file_length > 0) { 1515 /* Ignore errors, this is just a safeguard */ 1516 assert(hole == file_length); 1517 } 1518 *pnum = ROUND_UP(*pnum, bs->bl.request_alignment); 1519 } 1520 1521 ret = BDRV_BLOCK_DATA; 1522 } else { 1523 /* On a hole, compute bytes to the beginning of the next extent. */ 1524 assert(hole == offset); 1525 *pnum = data - offset; 1526 ret = BDRV_BLOCK_ZERO; 1527 } 1528 1529 *map = offset; 1530 *file = bs; 1531 1532 return ret | BDRV_BLOCK_OFFSET_VALID; 1533 } 1534 1535 1536 static const char *const gluster_strong_open_opts[] = { 1537 GLUSTER_OPT_VOLUME, 1538 GLUSTER_OPT_PATH, 1539 GLUSTER_OPT_TYPE, 1540 GLUSTER_OPT_SERVER_PATTERN, 1541 GLUSTER_OPT_HOST, 1542 GLUSTER_OPT_PORT, 1543 GLUSTER_OPT_TO, 1544 GLUSTER_OPT_IPV4, 1545 GLUSTER_OPT_IPV6, 1546 GLUSTER_OPT_SOCKET, 1547 1548 NULL 1549 }; 1550 1551 static BlockDriver bdrv_gluster = { 1552 .format_name = "gluster", 1553 .protocol_name = "gluster", 1554 .instance_size = sizeof(BDRVGlusterState), 1555 .bdrv_needs_filename = false, 1556 .bdrv_file_open = qemu_gluster_open, 1557 .bdrv_reopen_prepare = qemu_gluster_reopen_prepare, 1558 .bdrv_reopen_commit = qemu_gluster_reopen_commit, 1559 .bdrv_reopen_abort = qemu_gluster_reopen_abort, 1560 .bdrv_close = qemu_gluster_close, 1561 .bdrv_co_create = qemu_gluster_co_create, 1562 .bdrv_co_create_opts = qemu_gluster_co_create_opts, 1563 .bdrv_getlength = qemu_gluster_getlength, 1564 .bdrv_get_allocated_file_size = qemu_gluster_allocated_file_size, 1565 .bdrv_co_truncate = qemu_gluster_co_truncate, 1566 .bdrv_co_readv = qemu_gluster_co_readv, 1567 .bdrv_co_writev = qemu_gluster_co_writev, 1568 .bdrv_co_flush_to_disk = qemu_gluster_co_flush_to_disk, 1569 #ifdef CONFIG_GLUSTERFS_DISCARD 1570 .bdrv_co_pdiscard = qemu_gluster_co_pdiscard, 1571 #endif 1572 #ifdef CONFIG_GLUSTERFS_ZEROFILL 1573 .bdrv_co_pwrite_zeroes = qemu_gluster_co_pwrite_zeroes, 1574 #endif 1575 .bdrv_co_block_status = qemu_gluster_co_block_status, 1576 .bdrv_refresh_limits = qemu_gluster_refresh_limits, 1577 .create_opts = &qemu_gluster_create_opts, 1578 .strong_runtime_opts = gluster_strong_open_opts, 1579 }; 1580 1581 static BlockDriver bdrv_gluster_tcp = { 1582 .format_name = "gluster", 1583 .protocol_name = "gluster+tcp", 1584 .instance_size = sizeof(BDRVGlusterState), 1585 .bdrv_needs_filename = false, 1586 .bdrv_file_open = qemu_gluster_open, 1587 .bdrv_reopen_prepare = qemu_gluster_reopen_prepare, 1588 .bdrv_reopen_commit = qemu_gluster_reopen_commit, 1589 .bdrv_reopen_abort = qemu_gluster_reopen_abort, 1590 .bdrv_close = qemu_gluster_close, 1591 .bdrv_co_create = qemu_gluster_co_create, 1592 .bdrv_co_create_opts = qemu_gluster_co_create_opts, 1593 .bdrv_getlength = qemu_gluster_getlength, 1594 .bdrv_get_allocated_file_size = qemu_gluster_allocated_file_size, 1595 .bdrv_co_truncate = qemu_gluster_co_truncate, 1596 .bdrv_co_readv = qemu_gluster_co_readv, 1597 .bdrv_co_writev = qemu_gluster_co_writev, 1598 .bdrv_co_flush_to_disk = qemu_gluster_co_flush_to_disk, 1599 #ifdef CONFIG_GLUSTERFS_DISCARD 1600 .bdrv_co_pdiscard = qemu_gluster_co_pdiscard, 1601 #endif 1602 #ifdef CONFIG_GLUSTERFS_ZEROFILL 1603 .bdrv_co_pwrite_zeroes = qemu_gluster_co_pwrite_zeroes, 1604 #endif 1605 .bdrv_co_block_status = qemu_gluster_co_block_status, 1606 .bdrv_refresh_limits = qemu_gluster_refresh_limits, 1607 .create_opts = &qemu_gluster_create_opts, 1608 .strong_runtime_opts = gluster_strong_open_opts, 1609 }; 1610 1611 static BlockDriver bdrv_gluster_unix = { 1612 .format_name = "gluster", 1613 .protocol_name = "gluster+unix", 1614 .instance_size = sizeof(BDRVGlusterState), 1615 .bdrv_needs_filename = true, 1616 .bdrv_file_open = qemu_gluster_open, 1617 .bdrv_reopen_prepare = qemu_gluster_reopen_prepare, 1618 .bdrv_reopen_commit = qemu_gluster_reopen_commit, 1619 .bdrv_reopen_abort = qemu_gluster_reopen_abort, 1620 .bdrv_close = qemu_gluster_close, 1621 .bdrv_co_create = qemu_gluster_co_create, 1622 .bdrv_co_create_opts = qemu_gluster_co_create_opts, 1623 .bdrv_getlength = qemu_gluster_getlength, 1624 .bdrv_get_allocated_file_size = qemu_gluster_allocated_file_size, 1625 .bdrv_co_truncate = qemu_gluster_co_truncate, 1626 .bdrv_co_readv = qemu_gluster_co_readv, 1627 .bdrv_co_writev = qemu_gluster_co_writev, 1628 .bdrv_co_flush_to_disk = qemu_gluster_co_flush_to_disk, 1629 #ifdef CONFIG_GLUSTERFS_DISCARD 1630 .bdrv_co_pdiscard = qemu_gluster_co_pdiscard, 1631 #endif 1632 #ifdef CONFIG_GLUSTERFS_ZEROFILL 1633 .bdrv_co_pwrite_zeroes = qemu_gluster_co_pwrite_zeroes, 1634 #endif 1635 .bdrv_co_block_status = qemu_gluster_co_block_status, 1636 .bdrv_refresh_limits = qemu_gluster_refresh_limits, 1637 .create_opts = &qemu_gluster_create_opts, 1638 .strong_runtime_opts = gluster_strong_open_opts, 1639 }; 1640 1641 /* rdma is deprecated (actually never supported for volfile fetch). 1642 * Let's maintain it for the protocol compatibility, to make sure things 1643 * won't break immediately. For now, gluster+rdma will fall back to gluster+tcp 1644 * protocol with a warning. 1645 * TODO: remove gluster+rdma interface support 1646 */ 1647 static BlockDriver bdrv_gluster_rdma = { 1648 .format_name = "gluster", 1649 .protocol_name = "gluster+rdma", 1650 .instance_size = sizeof(BDRVGlusterState), 1651 .bdrv_needs_filename = true, 1652 .bdrv_file_open = qemu_gluster_open, 1653 .bdrv_reopen_prepare = qemu_gluster_reopen_prepare, 1654 .bdrv_reopen_commit = qemu_gluster_reopen_commit, 1655 .bdrv_reopen_abort = qemu_gluster_reopen_abort, 1656 .bdrv_close = qemu_gluster_close, 1657 .bdrv_co_create = qemu_gluster_co_create, 1658 .bdrv_co_create_opts = qemu_gluster_co_create_opts, 1659 .bdrv_getlength = qemu_gluster_getlength, 1660 .bdrv_get_allocated_file_size = qemu_gluster_allocated_file_size, 1661 .bdrv_co_truncate = qemu_gluster_co_truncate, 1662 .bdrv_co_readv = qemu_gluster_co_readv, 1663 .bdrv_co_writev = qemu_gluster_co_writev, 1664 .bdrv_co_flush_to_disk = qemu_gluster_co_flush_to_disk, 1665 #ifdef CONFIG_GLUSTERFS_DISCARD 1666 .bdrv_co_pdiscard = qemu_gluster_co_pdiscard, 1667 #endif 1668 #ifdef CONFIG_GLUSTERFS_ZEROFILL 1669 .bdrv_co_pwrite_zeroes = qemu_gluster_co_pwrite_zeroes, 1670 #endif 1671 .bdrv_co_block_status = qemu_gluster_co_block_status, 1672 .bdrv_refresh_limits = qemu_gluster_refresh_limits, 1673 .create_opts = &qemu_gluster_create_opts, 1674 .strong_runtime_opts = gluster_strong_open_opts, 1675 }; 1676 1677 static void bdrv_gluster_init(void) 1678 { 1679 bdrv_register(&bdrv_gluster_rdma); 1680 bdrv_register(&bdrv_gluster_unix); 1681 bdrv_register(&bdrv_gluster_tcp); 1682 bdrv_register(&bdrv_gluster); 1683 } 1684 1685 block_init(bdrv_gluster_init); 1686