If the file is readonly its not expected to grow so save the blocking call to nfs_fstat_async and use the value saved at connection time. Also important the monitor (and thus the main loop) will not hang if block device info is queried and the NFS share is unresponsive.
Signed-off-by: Peter Lieven <p...@kamp.de> --- block/nfs.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/block/nfs.c b/block/nfs.c index 02eb4e4..dc9ed21 100644 --- a/block/nfs.c +++ b/block/nfs.c @@ -43,6 +43,7 @@ typedef struct NFSClient { int events; bool has_zero_init; AioContext *aio_context; + blkcnt_t st_blocks; } NFSClient; typedef struct NFSRPC { @@ -374,6 +375,7 @@ static int64_t nfs_client_open(NFSClient *client, const char *filename, } ret = DIV_ROUND_UP(st.st_size, BDRV_SECTOR_SIZE); + client->st_blocks = st.st_blocks; client->has_zero_init = S_ISREG(st.st_mode); goto out; fail: @@ -464,6 +466,10 @@ static int64_t nfs_get_allocated_file_size(BlockDriverState *bs) NFSRPC task = {0}; struct stat st; + if (bdrv_is_read_only(bs)) { + return client->st_blocks * 512; + } + task.st = &st; if (nfs_fstat_async(client->context, client->fh, nfs_co_generic_cb, &task) != 0) { -- 1.9.1