From: Peter Lieven <p...@kamp.de> if the passed qiov contains exactly one iov we can pass the buffer directly.
Signed-off-by: Peter Lieven <p...@kamp.de> Reviewed-by: Jeff Cody <jc...@redhat.com> Message-id: 1487349541-10201-3-git-send-email...@kamp.de Signed-off-by: Jeff Cody <jc...@redhat.com> --- block/nfs.c | 35 ++++++++++++++++++++++------------- 1 file changed, 22 insertions(+), 13 deletions(-) diff --git a/block/nfs.c b/block/nfs.c index c11c4c9..ffb54be 100644 --- a/block/nfs.c +++ b/block/nfs.c @@ -302,30 +302,39 @@ static int coroutine_fn nfs_co_pwritev(BlockDriverState *bs, uint64_t offset, NFSClient *client = bs->opaque; NFSRPC task; char *buf = NULL; + bool my_buffer = false; nfs_co_init_task(bs, &task); - buf = g_try_malloc(bytes); - if (bytes && buf == NULL) { - return -ENOMEM; + if (iov->niov != 1) { + buf = g_try_malloc(bytes); + if (bytes && buf == NULL) { + return -ENOMEM; + } + qemu_iovec_to_buf(iov, 0, buf, bytes); + my_buffer = true; + } else { + buf = iov->iov[0].iov_base; } - qemu_iovec_to_buf(iov, 0, buf, bytes); - if (nfs_pwrite_async(client->context, client->fh, offset, bytes, buf, nfs_co_generic_cb, &task) != 0) { + if (my_buffer) { + g_free(buf); + } + return -ENOMEM; + } + + nfs_set_events(client); + while (!task.complete) { + qemu_coroutine_yield(); + } + + if (my_buffer) { g_free(buf); - return -ENOMEM; } - nfs_set_events(client); - while (!task.complete) { - qemu_coroutine_yield(); - } - - g_free(buf); - if (task.ret != bytes) { return task.ret < 0 ? task.ret : -EIO; } -- 2.9.3