/* * QEMU Block driver for NBD * * Copyright (C) 2008 Bull S.A.S. * Author: Laurent Vivier <Laurent.Vivier@bull.net> * * Some parts: * Copyright (C) 2007 Anthony Liguori <anthony@codemonkey.ws> * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal * in the Software without restriction, including without limitation the rights * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in * all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN * THE SOFTWARE. */ #include "block/nbd-client.h" #include "qemu/uri.h" #include "block/block_int.h" #include "qemu/module.h" #include "qemu/sockets.h" #include "qapi/qmp/qjson.h" #include "qapi/qmp/qint.h" #include <sys/types.h> #include <unistd.h> #define EN_OPTSTR ":exportname=" typedef struct BDRVNBDState { NbdClientSession client; QemuOpts *socket_opts; } BDRVNBDState; static int nbd_parse_uri(const char *filename, QDict *options) { URI *uri; const char *p; QueryParams *qp = NULL; int ret = 0; bool is_unix; uri = uri_parse(filename); if (!uri) { return -EINVAL; } /* transport */ if (!strcmp(uri->scheme, "nbd")) { is_unix = false; } else if (!strcmp(uri->scheme, "nbd+tcp")) { is_unix = false; } else if (!strcmp(uri->scheme, "nbd+unix")) { is_unix = true; } else { ret = -EINVAL; goto out; } p = uri->path ? uri->path : "/"; p += strspn(p, "/"); if (p[0]) { qdict_put(options, "export", qstring_from_str(p)); } qp = query_params_parse(uri->query); if (qp->n > 1 || (is_unix && !qp->n) || (!is_unix && qp->n)) { ret = -EINVAL; goto out; } if (is_unix) { /* nbd+unix:///export?socket=path */ if (uri->server || uri->port || strcmp(qp->p[0].name, "socket")) { ret = -EINVAL; goto out; } qdict_put(options, "path", qstring_from_str(qp->p[0].value)); } else { QString *host; /* nbd[+tcp]://host[:port]/export */ if (!uri->server) { ret = -EINVAL; goto out; } /* strip braces from literal IPv6 address */ if (uri->server[0] == '[') { host = qstring_from_substr(uri->server, 1, strlen(uri->server) - 2); } else { host = qstring_from_str(uri->server); } qdict_put(options, "host", host); if (uri->port) { char* port_str = g_strdup_printf("%d", uri->port); qdict_put(options, "port", qstring_from_str(port_str)); g_free(port_str); } } out: if (qp) { query_params_free(qp); } uri_free(uri); return ret; } static void nbd_parse_filename(const char *filename, QDict *options, Error **errp) { char *file; char *export_name; const char *host_spec; const char *unixpath; if (qdict_haskey(options, "host") || qdict_haskey(options, "port") || qdict_haskey(options, "path")) { error_setg(errp, "host/port/path and a file name may not be specified " "at the same time"); return; } if (strstr(filename, "://")) { int ret = nbd_parse_uri(filename, options); if (ret < 0) { error_setg(errp, "No valid URL specified"); } return; } file = g_strdup(filename); export_name = strstr(file, EN_OPTSTR); if (export_name) { if (export_name[strlen(EN_OPTSTR)] == 0) { goto out; } export_name[0] = 0; /* truncate 'file' */ export_name += strlen(EN_OPTSTR); qdict_put(options, "export", qstring_from_str(export_name)); } /* extract the host_spec - fail if it's not nbd:... */ if (!strstart(file, "nbd:", &host_spec)) { error_setg(errp, "File name string for NBD must start with 'nbd:'"); goto out; } if (!*host_spec) { goto out; } /* are we a UNIX or TCP socket? */ if (strstart(host_spec, "unix:", &unixpath)) { qdict_put(options, "path", qstring_from_str(unixpath)); } else { InetSocketAddress *addr = NULL; addr = inet_parse(host_spec, errp); if (error_is_set(errp)) { goto out; } qdict_put(options, "host", qstring_from_str(addr->host)); qdict_put(options, "port", qstring_from_str(addr->port)); qapi_free_InetSocketAddress(addr); } out: g_free(file); } static int nbd_config(BDRVNBDState *s, QDict *options, char **export) { Error *local_err = NULL; if (qdict_haskey(options, "path")) { if (qdict_haskey(options, "host")) { qerror_report(ERROR_CLASS_GENERIC_ERROR, "path and host may not " "be used at the same time."); return -EINVAL; } s->client.is_unix = true; } else if (qdict_haskey(options, "host")) { s->client.is_unix = false; } else { return -EINVAL; } s->socket_opts = qemu_opts_create(&socket_optslist, NULL, 0, &error_abort); qemu_opts_absorb_qdict(s->socket_opts, options, &local_err); if (local_err) { qerror_report_err(local_err); error_free(local_err); return -EINVAL; } if (!qemu_opt_get(s->socket_opts, "port")) { qemu_opt_set_number(s->socket_opts, "port", NBD_DEFAULT_PORT); } *export = g_strdup(qdict_get_try_str(options, "export")); if (*export) { qdict_del(options, "export"); } return 0; } static int nbd_establish_connection(BlockDriverState *bs) { BDRVNBDState *s = bs->opaque; int sock; if (s->client.is_unix) { sock = unix_socket_outgoing(qemu_opt_get(s->socket_opts, "path")); } else { sock = tcp_socket_outgoing_opts(s->socket_opts); if (sock >= 0) { socket_set_nodelay(sock); } } /* Failed to establish connection */ if (sock < 0) { logout("Failed to establish connection to NBD server\n"); return -errno; } return sock; } static int nbd_open(BlockDriverState *bs, QDict *options, int flags, Error **errp) { BDRVNBDState *s = bs->opaque; char *export = NULL; int result, sock; /* Pop the config into our state object. Exit if invalid. */ result = nbd_config(s, options, &export); if (result != 0) { return result; } /* establish TCP connection, return error if it fails * TODO: Configurable retry-until-timeout behaviour. */ sock = nbd_establish_connection(bs); if (sock < 0) { return sock; } /* NBD handshake */ result = nbd_client_session_init(&s->client, bs, sock, export); g_free(export); return result; } static int nbd_co_readv(BlockDriverState *bs, int64_t sector_num, int nb_sectors, QEMUIOVector *qiov) { BDRVNBDState *s = bs->opaque; return nbd_client_session_co_readv(&s->client, sector_num, nb_sectors, qiov); } static int nbd_co_writev(BlockDriverState *bs, int64_t sector_num, int nb_sectors, QEMUIOVector *qiov) { BDRVNBDState *s = bs->opaque; return nbd_client_session_co_writev(&s->client, sector_num, nb_sectors, qiov); } static int nbd_co_flush(BlockDriverState *bs) { BDRVNBDState *s = bs->opaque; return nbd_client_session_co_flush(&s->client); } static int nbd_co_discard(BlockDriverState *bs, int64_t sector_num, int nb_sectors) { BDRVNBDState *s = bs->opaque; return nbd_client_session_co_discard(&s->client, sector_num, nb_sectors); } static void nbd_close(BlockDriverState *bs) { BDRVNBDState *s = bs->opaque; qemu_opts_del(s->socket_opts); nbd_client_session_close(&s->client); } static int64_t nbd_getlength(BlockDriverState *bs) { BDRVNBDState *s = bs->opaque; return s->client.size; } static BlockDriver bdrv_nbd = { .format_name = "nbd", .protocol_name = "nbd", .instance_size = sizeof(BDRVNBDState), .bdrv_parse_filename = nbd_parse_filename, .bdrv_file_open = nbd_open, .bdrv_co_readv = nbd_co_readv, .bdrv_co_writev = nbd_co_writev, .bdrv_close = nbd_close, .bdrv_co_flush_to_os = nbd_co_flush, .bdrv_co_discard = nbd_co_discard, .bdrv_getlength = nbd_getlength, }; static BlockDriver bdrv_nbd_tcp = { .format_name = "nbd", .protocol_name = "nbd+tcp", .instance_size = sizeof(BDRVNBDState), .bdrv_parse_filename = nbd_parse_filename, .bdrv_file_open = nbd_open, .bdrv_co_readv = nbd_co_readv, .bdrv_co_writev = nbd_co_writev, .bdrv_close = nbd_close, .bdrv_co_flush_to_os = nbd_co_flush, .bdrv_co_discard = nbd_co_discard, .bdrv_getlength = nbd_getlength, }; static BlockDriver bdrv_nbd_unix = { .format_name = "nbd", .protocol_name = "nbd+unix", .instance_size = sizeof(BDRVNBDState), .bdrv_parse_filename = nbd_parse_filename, .bdrv_file_open = nbd_open, .bdrv_co_readv = nbd_co_readv, .bdrv_co_writev = nbd_co_writev, .bdrv_close = nbd_close, .bdrv_co_flush_to_os = nbd_co_flush, .bdrv_co_discard = nbd_co_discard, .bdrv_getlength = nbd_getlength, }; static void bdrv_nbd_init(void) { bdrv_register(&bdrv_nbd); bdrv_register(&bdrv_nbd_tcp); bdrv_register(&bdrv_nbd_unix); } block_init(bdrv_nbd_init);