Without this callback, there will be an error reports in the primary side: "qemu-system-x86_64: Couldn't determine the cluster size of the target image, which has no backing file: Operation not supported Aborting, since this may create an unusable destination image"
For nbd driver, it doesn't have cluster size, so here we return a fake value for it. This patch should be dropped if Eric's nbd patch be merged. https://lists.gnu.org/archive/html/qemu-devel/2016-04/msg03567.html Cc: Eric Blake <ebl...@redhat.com> Signed-off-by: zhanghailiang <zhang.zhanghaili...@huawei.com> Signed-off-by: Wen Congyang <we...@cn.fujitsu.com> --- block/nbd.c | 12 ++++++++++++ block/replication.c | 6 ++++++ 2 files changed, 18 insertions(+) diff --git a/block/nbd.c b/block/nbd.c index 35f24be..b71a13d 100644 --- a/block/nbd.c +++ b/block/nbd.c @@ -43,6 +43,8 @@ #define EN_OPTSTR ":exportname=" +#define NBD_FAKE_CLUSTER_SIZE 512 + typedef struct BDRVNBDState { NBDClientSession client; @@ -552,6 +554,13 @@ static void nbd_refresh_filename(BlockDriverState *bs, QDict *options) bs->full_open_options = opts; } +static int nbd_get_info(BlockDriverState *bs, BlockDriverInfo *bdi) +{ + bdi->cluster_size = NBD_FAKE_CLUSTER_SIZE; + + return 0; +} + static BlockDriver bdrv_nbd = { .format_name = "nbd", .protocol_name = "nbd", @@ -569,6 +578,7 @@ static BlockDriver bdrv_nbd = { .bdrv_detach_aio_context = nbd_detach_aio_context, .bdrv_attach_aio_context = nbd_attach_aio_context, .bdrv_refresh_filename = nbd_refresh_filename, + .bdrv_get_info = nbd_get_info, }; static BlockDriver bdrv_nbd_tcp = { @@ -588,6 +598,7 @@ static BlockDriver bdrv_nbd_tcp = { .bdrv_detach_aio_context = nbd_detach_aio_context, .bdrv_attach_aio_context = nbd_attach_aio_context, .bdrv_refresh_filename = nbd_refresh_filename, + .bdrv_get_info = nbd_get_info, }; static BlockDriver bdrv_nbd_unix = { @@ -607,6 +618,7 @@ static BlockDriver bdrv_nbd_unix = { .bdrv_detach_aio_context = nbd_detach_aio_context, .bdrv_attach_aio_context = nbd_attach_aio_context, .bdrv_refresh_filename = nbd_refresh_filename, + .bdrv_get_info = nbd_get_info, }; static void bdrv_nbd_init(void) diff --git a/block/replication.c b/block/replication.c index a0b3e41..e4f8069 100644 --- a/block/replication.c +++ b/block/replication.c @@ -731,6 +731,11 @@ static void replication_stop(ReplicationState *rs, bool failover, Error **errp) aio_context_release(aio_context); } +static int replication_get_info(BlockDriverState *bs, BlockDriverInfo *bdi) +{ + return bdrv_get_info(bs->file->bs, bdi); +} + BlockDriver bdrv_replication = { .format_name = "replication", .protocol_name = "replication", @@ -743,6 +748,7 @@ BlockDriver bdrv_replication = { .bdrv_co_readv = replication_co_readv, .bdrv_co_writev = replication_co_writev, + .bdrv_get_info = replication_get_info, .is_filter = true, .bdrv_recurse_is_first_non_filter = replication_recurse_is_first_non_filter, -- 1.8.3.1