@@ -20,6 +20,10 @@
#include "qapi/error.h"
#include "nbd-internal.h"
+/* nbd_wr_syncv
+ * The function may be called from coroutine or from non-coroutine context.
+ * When called from non-coroutine context @ioc must be in blocking mode.
+ */
ssize_t nbd_wr_syncv(QIOChannel *ioc,
struct iovec *iov,
size_t niov,
@@ -42,11 +46,8 @@ ssize_t nbd_wr_syncv(QIOChannel *ioc,
len = qio_channel_writev(ioc, local_iov, nlocal_iov, &local_err);
}
if (len == QIO_CHANNEL_ERR_BLOCK) {
- if (qemu_in_coroutine()) {
- qio_channel_yield(ioc, do_read ? G_IO_IN : G_IO_OUT);
- } else {
- return -EAGAIN;
- }
+ assert(qemu_in_coroutine());
+ qio_channel_yield(ioc, do_read ? G_IO_IN : G_IO_OUT);
continue;
}
if (len < 0) {
nbd_wr_syncv is called either from coroutine or from client negotiation code, when socket is in blocking mode. So, -EAGAIN is impossible. Furthermore, EAGAIN is confusing, as, what to read/write again? With EAGAIN as a return code we don't know how much data is already read or written by the function, so in case of EAGAIN the whole communication is broken. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com> --- nbd/common.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-)