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-rw-r--r--src/block/nbd.c451
1 files changed, 451 insertions, 0 deletions
diff --git a/src/block/nbd.c b/src/block/nbd.c
new file mode 100644
index 0000000..cd6a587
--- /dev/null
+++ b/src/block/nbd.c
@@ -0,0 +1,451 @@
+/*
+ * 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);
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