/* * 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/qdict.h" #include "qapi/qmp/qjson.h" #include "qapi/qmp/qint.h" #include "qapi/qmp/qstring.h" #include <sys/types.h> #include <unistd.h> #define EN_OPTSTR ":exportname=" typedef struct BDRVNBDState { NbdClientSession client; } 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 (!addr) { 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 SocketAddress *nbd_config(BDRVNBDState *s, QDict *options, char **export, Error **errp) { SocketAddress *saddr; if (qdict_haskey(options, "path") == qdict_haskey(options, "host")) { if (qdict_haskey(options, "path")) { error_setg(errp, "path and host may not be used at the same time."); } else { error_setg(errp, "one of path and host must be specified."); } return NULL; } saddr = g_new0(SocketAddress, 1); if (qdict_haskey(options, "path")) { saddr->type = SOCKET_ADDRESS_KIND_UNIX; saddr->u.q_unix = g_new0(UnixSocketAddress, 1); saddr->u.q_unix->path = g_strdup(qdict_get_str(options, "path")); qdict_del(options, "path"); } else { saddr->type = SOCKET_ADDRESS_KIND_INET; saddr->u.inet = g_new0(InetSocketAddress, 1); saddr->u.inet->host = g_strdup(qdict_get_str(options, "host")); if (!qdict_get_try_str(options, "port")) { saddr->u.inet->port = g_strdup_printf("%d", NBD_DEFAULT_PORT); } else { saddr->u.inet->port = g_strdup(qdict_get_str(options, "port")); } qdict_del(options, "host"); qdict_del(options, "port"); } s->client.is_unix = saddr->type == SOCKET_ADDRESS_KIND_UNIX; *export = g_strdup(qdict_get_try_str(options, "export")); if (*export) { qdict_del(options, "export"); } return saddr; } NbdClientSession *nbd_get_client_session(BlockDriverState *bs) { BDRVNBDState *s = bs->opaque; return &s->client; } static int nbd_establish_connection(BlockDriverState *bs, SocketAddress *saddr, Error **errp) { BDRVNBDState *s = bs->opaque; int sock; sock = socket_connect(saddr, errp, NULL, NULL); if (sock < 0) { logout("Failed to establish connection to NBD server\n"); return -EIO; } if (!s->client.is_unix) { socket_set_nodelay(sock); } return sock; } static int nbd_open(BlockDriverState *bs, QDict *options, int flags, Error **errp) { BDRVNBDState *s = bs->opaque; char *export = NULL; int result, sock; SocketAddress *saddr; /* Pop the config into our state object. Exit if invalid. */ saddr = nbd_config(s, options, &export, errp); if (!saddr) { return -EINVAL; } /* establish TCP connection, return error if it fails * TODO: Configurable retry-until-timeout behaviour. */ sock = nbd_establish_connection(bs, saddr, errp); qapi_free_SocketAddress(saddr); if (sock < 0) { g_free(export); return sock; } /* NBD handshake */ result = nbd_client_init(bs, sock, export, errp); g_free(export); return result; } static int nbd_co_readv(BlockDriverState *bs, int64_t sector_num, int nb_sectors, QEMUIOVector *qiov) { return nbd_client_co_readv(bs, sector_num, nb_sectors, qiov); } static int nbd_co_writev(BlockDriverState *bs, int64_t sector_num, int nb_sectors, QEMUIOVector *qiov) { return nbd_client_co_writev(bs, sector_num, nb_sectors, qiov); } static int nbd_co_flush(BlockDriverState *bs) { return nbd_client_co_flush(bs); } static void nbd_refresh_limits(BlockDriverState *bs, Error **errp) { bs->bl.max_discard = UINT32_MAX >> BDRV_SECTOR_BITS; bs->bl.max_transfer_length = UINT32_MAX >> BDRV_SECTOR_BITS; } static int nbd_co_discard(BlockDriverState *bs, int64_t sector_num, int nb_sectors) { return nbd_client_co_discard(bs, sector_num, nb_sectors); } static void nbd_close(BlockDriverState *bs) { nbd_client_close(bs); } static int64_t nbd_getlength(BlockDriverState *bs) { BDRVNBDState *s = bs->opaque; return s->client.size; } static void nbd_detach_aio_context(BlockDriverState *bs) { nbd_client_detach_aio_context(bs); } static void nbd_attach_aio_context(BlockDriverState *bs, AioContext *new_context) { nbd_client_attach_aio_context(bs, new_context); } static void nbd_refresh_filename(BlockDriverState *bs) { QDict *opts = qdict_new(); const char *path = qdict_get_try_str(bs->options, "path"); const char *host = qdict_get_try_str(bs->options, "host"); const char *port = qdict_get_try_str(bs->options, "port"); const char *export = qdict_get_try_str(bs->options, "export"); qdict_put_obj(opts, "driver", QOBJECT(qstring_from_str("nbd"))); if (path && export) { snprintf(bs->exact_filename, sizeof(bs->exact_filename), "nbd+unix:///%s?socket=%s", export, path); } else if (path && !export) { snprintf(bs->exact_filename, sizeof(bs->exact_filename), "nbd+unix://?socket=%s", path); } else if (!path && export && port) { snprintf(bs->exact_filename, sizeof(bs->exact_filename), "nbd://%s:%s/%s", host, port, export); } else if (!path && export && !port) { snprintf(bs->exact_filename, sizeof(bs->exact_filename), "nbd://%s/%s", host, export); } else if (!path && !export && port) { snprintf(bs->exact_filename, sizeof(bs->exact_filename), "nbd://%s:%s", host, port); } else if (!path && !export && !port) { snprintf(bs->exact_filename, sizeof(bs->exact_filename), "nbd://%s", host); } if (path) { qdict_put_obj(opts, "path", QOBJECT(qstring_from_str(path))); } else if (port) { qdict_put_obj(opts, "host", QOBJECT(qstring_from_str(host))); qdict_put_obj(opts, "port", QOBJECT(qstring_from_str(port))); } else { qdict_put_obj(opts, "host", QOBJECT(qstring_from_str(host))); } if (export) { qdict_put_obj(opts, "export", QOBJECT(qstring_from_str(export))); } bs->full_open_options = opts; } 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_refresh_limits = nbd_refresh_limits, .bdrv_getlength = nbd_getlength, .bdrv_detach_aio_context = nbd_detach_aio_context, .bdrv_attach_aio_context = nbd_attach_aio_context, .bdrv_refresh_filename = nbd_refresh_filename, }; 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_refresh_limits = nbd_refresh_limits, .bdrv_getlength = nbd_getlength, .bdrv_detach_aio_context = nbd_detach_aio_context, .bdrv_attach_aio_context = nbd_attach_aio_context, .bdrv_refresh_filename = nbd_refresh_filename, }; 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_refresh_limits = nbd_refresh_limits, .bdrv_getlength = nbd_getlength, .bdrv_detach_aio_context = nbd_detach_aio_context, .bdrv_attach_aio_context = nbd_attach_aio_context, .bdrv_refresh_filename = nbd_refresh_filename, }; 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);