Hi
On Thu, Aug 24, 2017 at 12:27 PM, Dr. David Alan Gilbert (git)
<[email protected]> wrote:
> From: "Dr. David Alan Gilbert" <[email protected]>
>
> Allow replies with fds (for postcopy)
>
> Signed-off-by: Dr. David Alan Gilbert <[email protected]>
> ---
> contrib/libvhost-user/libvhost-user.c | 29 ++++++++++++++++++++++++++++-
> 1 file changed, 28 insertions(+), 1 deletion(-)
>
> diff --git a/contrib/libvhost-user/libvhost-user.c
> b/contrib/libvhost-user/libvhost-user.c
> index 8bbdf5fb40..47884c0a15 100644
> --- a/contrib/libvhost-user/libvhost-user.c
> +++ b/contrib/libvhost-user/libvhost-user.c
> @@ -213,6 +213,30 @@ vu_message_write(VuDev *dev, int conn_fd, VhostUserMsg
> *vmsg)
> {
> int rc;
> uint8_t *p = (uint8_t *)vmsg;
> + char control[CMSG_SPACE(VHOST_MEMORY_MAX_NREGIONS * sizeof(int))] = { };
> + struct iovec iov = {
> + .iov_base = (char *)vmsg,
> + .iov_len = VHOST_USER_HDR_SIZE,
> + };
> + struct msghdr msg = {
> + .msg_iov = &iov,
> + .msg_iovlen = 1,
> + .msg_control = control,
> + };
> + struct cmsghdr *cmsg;
> +
> + memset(control, 0, sizeof(control));
> + if (vmsg->fds) {
This is going to be always true, right? Check vmsg->fd_num > 0 instead?
I would also add check or assert(vmsg->fd_num <= VHOST_MEMORY_MAX_NREGIONS)
> + size_t fdsize = vmsg->fd_num * sizeof(int);
> + msg.msg_controllen = CMSG_SPACE(fdsize);
> + cmsg = CMSG_FIRSTHDR(&msg);
> + cmsg->cmsg_len = CMSG_LEN(fdsize);
> + cmsg->cmsg_level = SOL_SOCKET;
> + cmsg->cmsg_type = SCM_RIGHTS;
> + memcpy(CMSG_DATA(cmsg), vmsg->fds, fdsize);
> + } else {
> + msg.msg_controllen = 0;
> + }
>
> /* Set the version in the flags when sending the reply */
> vmsg->flags &= ~VHOST_USER_VERSION_MASK;
> @@ -220,7 +244,7 @@ vu_message_write(VuDev *dev, int conn_fd, VhostUserMsg
> *vmsg)
> vmsg->flags |= VHOST_USER_REPLY_MASK;
>
> do {
> - rc = write(conn_fd, p, VHOST_USER_HDR_SIZE);
> + rc = sendmsg(conn_fd, &msg, 0);
> } while (rc < 0 && (errno == EINTR || errno == EAGAIN));
>
> do {
> @@ -313,6 +337,7 @@ vu_get_features_exec(VuDev *dev, VhostUserMsg *vmsg)
> }
>
> vmsg->size = sizeof(vmsg->payload.u64);
> + vmsg->fd_num = 0;
>
> DPRINT("Sending back to guest u64: 0x%016"PRIx64"\n", vmsg->payload.u64);
>
> @@ -454,6 +479,7 @@ vu_set_log_base_exec(VuDev *dev, VhostUserMsg *vmsg)
> dev->log_size = log_mmap_size;
>
> vmsg->size = sizeof(vmsg->payload.u64);
> + vmsg->fd_num = 0;
>
> return true;
> }
> @@ -698,6 +724,7 @@ vu_get_protocol_features_exec(VuDev *dev, VhostUserMsg
> *vmsg)
>
> vmsg->payload.u64 = features;
> vmsg->size = sizeof(vmsg->payload.u64);
> + vmsg->fd_num = 0;
>
> return true;
> }
> --
> 2.13.5
>
>
other than that
Reviewed-by: Marc-André Lureau <[email protected]>
--
Marc-André Lureau
