@@ -105,6 +105,8 @@
#
# Export a block node to QEMU's embedded NBD server.
#
+# The export name will be used as the id for the resulting block export.
+#
# Returns: error if the server is not running, or export with the same name
# already exists.
#
@@ -182,6 +184,8 @@
# Describes a block export, i.e. how single node should be exported on an
# external interface.
#
+# @id: A unique identifier for the block export (across all export types)
+#
# @node-name: The node name of the block node to be exported (since: 5.2)
#
# @writethrough: If true, caches are flushed after every write request to the
@@ -192,6 +196,7 @@
##
{ 'union': 'BlockExportOptions',
'base': { 'type': 'BlockExportType',
+ 'id': 'str',
'node-name': 'str',
'*writethrough': 'bool' },
'discriminator': 'type',
@@ -50,6 +50,9 @@ typedef struct BlockExportDriver {
struct BlockExport {
const BlockExportDriver *drv;
+ /* Unique identifier for the export */
+ char *id;
+
/*
* Reference count for this block export. This includes strong references
* both from the owner (qemu-nbd or the monitor) and clients connected to
@@ -19,6 +19,7 @@
#include "block/nbd.h"
#include "qapi/error.h"
#include "qapi/qapi-commands-block-export.h"
+#include "qemu/id.h"
static const BlockExportDriver *blk_exp_drivers[] = {
&blk_exp_nbd,
@@ -28,6 +29,19 @@ static const BlockExportDriver *blk_exp_drivers[] = {
static QLIST_HEAD(, BlockExport) block_exports =
QLIST_HEAD_INITIALIZER(block_exports);
+static BlockExport *blk_exp_find(const char *id)
+{
+ BlockExport *exp;
+
+ QLIST_FOREACH(exp, &block_exports, next) {
+ if (strcmp(id, exp->id) == 0) {
+ return exp;
+ }
+ }
+
+ return NULL;
+}
+
static const BlockExportDriver *blk_exp_find_driver(BlockExportType type)
{
int i;
@@ -46,6 +60,15 @@ BlockExport *blk_exp_add(BlockExportOptions *export, Error **errp)
BlockExport *exp;
int ret;
+ if (!id_wellformed(export->id)) {
+ error_setg(errp, "Invalid block export id");
+ return NULL;
+ }
+ if (blk_exp_find(export->id)) {
+ error_setg(errp, "Block export id '%s' is already in use", export->id);
+ return NULL;
+ }
+
drv = blk_exp_find_driver(export->type);
if (!drv) {
error_setg(errp, "No driver found for the requested export type");
@@ -57,10 +80,12 @@ BlockExport *blk_exp_add(BlockExportOptions *export, Error **errp)
*exp = (BlockExport) {
.drv = drv,
.refcount = 1,
+ .id = g_strdup(export->id),
};
ret = drv->create(exp, export, errp);
if (ret < 0) {
+ g_free(exp->id);
g_free(exp);
return NULL;
}
@@ -87,6 +112,7 @@ static void blk_exp_delete_bh(void *opaque)
assert(exp->refcount == 0);
QLIST_REMOVE(exp, next);
exp->drv->delete(exp);
+ g_free(exp->id);
g_free(exp);
aio_context_release(aio_context);
@@ -269,6 +269,7 @@ void qmp_nbd_server_add(NbdServerAddOptions *arg, Error **errp)
export_opts = g_new(BlockExportOptions, 1);
*export_opts = (BlockExportOptions) {
.type = BLOCK_EXPORT_TYPE_NBD,
+ .id = g_strdup(arg->name),
.node_name = g_strdup(bdrv_get_node_name(bs)),
.u.nbd = {
.has_name = true,
@@ -1064,6 +1064,7 @@ int main(int argc, char **argv)
export_opts = g_new(BlockExportOptions, 1);
*export_opts = (BlockExportOptions) {
.type = BLOCK_EXPORT_TYPE_NBD,
+ .id = g_strdup("qemu-nbd-export"),
.node_name = g_strdup(bdrv_get_node_name(bs)),
.has_writethrough = true,
.writethrough = writethrough,
@@ -92,7 +92,7 @@ static void help(void)
" --chardev <options> configure a character device backend\n"
" (see the qemu(1) man page for possible options)\n"
"\n"
-" --export [type=]nbd,device=<node-name>[,name=<export-name>]\n"
+" --export [type=]nbd,device=<node-name>,id=<id>,[,name=<export-name>]\n"
" [,writable=on|off][,bitmap=<name>]\n"
" export the specified block node over NBD\n"
" (requires --nbd-server)\n"
@@ -45,7 +45,7 @@ exports available: 0
{"execute":"nbd-server-add", "arguments":{"device":"nosuch"}}
{"error": {"class": "GenericError", "desc": "Cannot find device=nosuch nor node_name=nosuch"}}
{"execute":"nbd-server-add", "arguments":{"device":"n"}}
-{"error": {"class": "GenericError", "desc": "NBD server already has export named 'n'"}}
+{"error": {"class": "GenericError", "desc": "Block export id 'n' is already in use"}}
{"execute":"nbd-server-add", "arguments":{"device":"n", "name":"n2", "bitmap":"b2"}}
{"error": {"class": "GenericError", "desc": "Enabled bitmap 'b2' incompatible with readonly export"}}
{"execute":"nbd-server-add", "arguments":{"device":"n", "name":"n2", "bitmap":"b3"}}
@@ -126,7 +126,7 @@ exports available: 0
{"execute":"nbd-server-add", "arguments":{"device":"nosuch"}}
{"error": {"class": "GenericError", "desc": "Cannot find device=nosuch nor node_name=nosuch"}}
{"execute":"nbd-server-add", "arguments":{"device":"n"}}
-{"error": {"class": "GenericError", "desc": "NBD server already has export named 'n'"}}
+{"error": {"class": "GenericError", "desc": "Block export id 'n' is already in use"}}
{"execute":"nbd-server-add", "arguments":{"device":"n", "name":"n2", "bitmap":"b2"}}
{"error": {"class": "GenericError", "desc": "Enabled bitmap 'b2' incompatible with readonly export"}}
{"execute":"nbd-server-add", "arguments":{"device":"n", "name":"n2", "bitmap":"b3"}}