@@ -22,8 +22,14 @@ typedef struct BlockExportDriver {
/* The export type that this driver services */
BlockExportType type;
+ /*
+ * The size of the driver-specific state that contains BlockExport as its
+ * first field.
+ */
+ size_t instance_size;
+
/* Creates and starts a new block export */
- BlockExport *(*create)(BlockExportOptions *, Error **);
+ int (*create)(BlockExport *, BlockExportOptions *, Error **);
/*
* Frees a removed block export. This function is only called after all
@@ -330,11 +330,12 @@ int nbd_errno_to_system_errno(int err);
typedef struct NBDExport NBDExport;
typedef struct NBDClient NBDClient;
-BlockExport *nbd_export_create(BlockExportOptions *exp_args, Error **errp);
-NBDExport *nbd_export_new(BlockDriverState *bs,
- const char *name, const char *desc,
- const char *bitmap, bool readonly, bool shared,
- bool writethrough, Error **errp);
+int nbd_export_create(BlockExport *exp, BlockExportOptions *exp_args,
+ Error **errp);
+int nbd_export_new(BlockExport *blk_exp, BlockDriverState *bs,
+ const char *name, const char *desc,
+ const char *bitmap, bool readonly, bool shared,
+ bool writethrough, Error **errp);
void nbd_export_set_on_eject_blk(BlockExport *exp, BlockBackend *blk);
void nbd_export_close(NBDExport *exp);
void nbd_export_remove(NBDExport *exp, NbdServerRemoveMode mode, Error **errp);
@@ -39,6 +39,8 @@ static const BlockExportDriver *blk_exp_find_driver(BlockExportType type)
BlockExport *blk_exp_add(BlockExportOptions *export, Error **errp)
{
const BlockExportDriver *drv;
+ BlockExport *exp;
+ int ret;
drv = blk_exp_find_driver(export->type);
if (!drv) {
@@ -46,7 +48,20 @@ BlockExport *blk_exp_add(BlockExportOptions *export, Error **errp)
return NULL;
}
- return drv->create(export, errp);
+ assert(drv->instance_size >= sizeof(BlockExport));
+ exp = g_malloc0(drv->instance_size);
+ *exp = (BlockExport) {
+ .drv = drv,
+ .refcount = 1,
+ };
+
+ ret = drv->create(exp, export, errp);
+ if (ret < 0) {
+ g_free(exp);
+ return NULL;
+ }
+
+ return exp;
}
/* Callers must hold exp->ctx lock */
@@ -62,6 +77,7 @@ void blk_exp_unref(BlockExport *exp)
assert(exp->refcount > 0);
if (--exp->refcount == 0) {
exp->drv->delete(exp);
+ g_free(exp);
}
}
@@ -173,18 +173,19 @@ void qmp_nbd_server_start(SocketAddressLegacy *addr,
qapi_free_SocketAddress(addr_flat);
}
-BlockExport *nbd_export_create(BlockExportOptions *exp_args, Error **errp)
+int nbd_export_create(BlockExport *exp, BlockExportOptions *exp_args,
+ Error **errp)
{
BlockExportOptionsNbd *arg = &exp_args->u.nbd;
BlockDriverState *bs = NULL;
- NBDExport *exp = NULL;
AioContext *aio_context;
+ int ret;
assert(exp_args->type == BLOCK_EXPORT_TYPE_NBD);
if (!nbd_server && !is_qemu_nbd) {
error_setg(errp, "NBD server not running");
- return NULL;
+ return -EINVAL;
}
if (!arg->has_name) {
@@ -193,22 +194,22 @@ BlockExport *nbd_export_create(BlockExportOptions *exp_args, Error **errp)
if (strlen(arg->name) > NBD_MAX_STRING_SIZE) {
error_setg(errp, "export name '%s' too long", arg->name);
- return NULL;
+ return -EINVAL;
}
if (arg->description && strlen(arg->description) > NBD_MAX_STRING_SIZE) {
error_setg(errp, "description '%s' too long", arg->description);
- return NULL;
+ return -EINVAL;
}
if (nbd_export_find(arg->name)) {
error_setg(errp, "NBD server already has export named '%s'", arg->name);
- return NULL;
+ return -EEXIST;
}
bs = bdrv_lookup_bs(NULL, exp_args->node_name, errp);
if (!bs) {
- return NULL;
+ return -ENOENT;
}
aio_context = bdrv_get_aio_context(bs);
@@ -218,6 +219,7 @@ BlockExport *nbd_export_create(BlockExportOptions *exp_args, Error **errp)
arg->writable = false;
}
if (bdrv_is_read_only(bs) && arg->writable) {
+ ret = -EINVAL;
error_setg(errp, "Cannot export read-only node as writable");
goto out;
}
@@ -226,22 +228,22 @@ BlockExport *nbd_export_create(BlockExportOptions *exp_args, Error **errp)
exp_args->writethrough = false;
}
- exp = nbd_export_new(bs, arg->name, arg->description, arg->bitmap,
+ ret = nbd_export_new(exp, bs, arg->name, arg->description, arg->bitmap,
!arg->writable, !arg->writable,
exp_args->writethrough, errp);
- if (!exp) {
+ if (ret < 0) {
goto out;
}
/* The list of named exports has a strong reference to this export now and
* our only way of accessing it is through nbd_export_find(), so we can drop
* the strong reference that is @exp. */
- blk_exp_unref((BlockExport*) exp);
+ blk_exp_unref(exp);
+ ret = 0;
out:
aio_context_release(aio_context);
- /* TODO Remove the cast: nbd_export_new() will return a BlockExport. */
- return (BlockExport*) exp;
+ return ret;
}
void qmp_nbd_server_add(NbdServerAddOptions *arg, Error **errp)
@@ -1514,14 +1514,14 @@ void nbd_export_set_on_eject_blk(BlockExport *exp, BlockBackend *blk)
blk_add_remove_bs_notifier(blk, &nbd_exp->eject_notifier);
}
-NBDExport *nbd_export_new(BlockDriverState *bs,
- const char *name, const char *desc,
- const char *bitmap, bool readonly, bool shared,
- bool writethrough, Error **errp)
+int nbd_export_new(BlockExport *blk_exp, BlockDriverState *bs,
+ const char *name, const char *desc,
+ const char *bitmap, bool readonly, bool shared,
+ bool writethrough, Error **errp)
{
+ NBDExport *exp = container_of(blk_exp, NBDExport, common);
AioContext *ctx;
BlockBackend *blk;
- NBDExport *exp;
int64_t size;
uint64_t perm;
int ret;
@@ -1530,17 +1530,11 @@ NBDExport *nbd_export_new(BlockDriverState *bs,
if (size < 0) {
error_setg_errno(errp, -size,
"Failed to determine the NBD export's length");
- return NULL;
+ return size;
}
ctx = bdrv_get_aio_context(bs);
-
- exp = g_new0(NBDExport, 1);
- exp->common = (BlockExport) {
- .drv = &blk_exp_nbd,
- .refcount = 1,
- .ctx = ctx,
- };
+ blk_exp->ctx = ctx;
/*
* NBD exports are used for non-shared storage migration. Make sure
@@ -1599,16 +1593,19 @@ NBDExport *nbd_export_new(BlockDriverState *bs,
}
if (bm == NULL) {
+ ret = -ENOENT;
error_setg(errp, "Bitmap '%s' is not found", bitmap);
goto fail;
}
if (bdrv_dirty_bitmap_check(bm, BDRV_BITMAP_ALLOW_RO, errp)) {
+ ret = -EINVAL;
goto fail;
}
if (readonly && bdrv_is_writable(bs) &&
bdrv_dirty_bitmap_enabled(bm)) {
+ ret = -EINVAL;
error_setg(errp,
"Enabled bitmap '%s' incompatible with readonly export",
bitmap);
@@ -1628,14 +1625,13 @@ NBDExport *nbd_export_new(BlockDriverState *bs,
blk_exp_ref(&exp->common);
QTAILQ_INSERT_TAIL(&exports, exp, next);
- return exp;
+ return 0;
fail:
blk_unref(blk);
g_free(exp->name);
g_free(exp->description);
- g_free(exp);
- return NULL;
+ return ret;
}
NBDExport *nbd_export_find(const char *name)
@@ -1722,12 +1718,12 @@ static void nbd_export_delete(BlockExport *blk_exp)
}
QTAILQ_REMOVE(&closed_exports, exp, next);
- g_free(exp);
aio_wait_kick();
}
const BlockExportDriver blk_exp_nbd = {
.type = BLOCK_EXPORT_TYPE_NBD,
+ .instance_size = sizeof(NBDExport),
.create = nbd_export_create,
.delete = nbd_export_delete,
};