Merge remote-tracking branch 'mst/tags/for_anthony' into staging

* mst/tags/for_anthony:
  virtio-serial-bus: let chardev know the exact number of bytes requested
  virtio: Introduce virtqueue_get_avail_bytes()
  virtio: use unsigned int for counting bytes in vq
  iov: add const annotation
  virtio-net: fix used len for tx
  virtio: don't mark unaccessed memory as dirty

hw/virtio-net.c

@@ -690,7 +690,7 @@ static void virtio_net_tx_complete(NetClientState *nc, ssize_t len)
 {
     VirtIONet *n = DO_UPCAST(NICState, nc, nc)->opaque;
 
-    virtqueue_push(n->tx_vq, &n->async_tx.elem, n->async_tx.len);
+    virtqueue_push(n->tx_vq, &n->async_tx.elem, 0);
     virtio_notify(&n->vdev, n->tx_vq);
 
     n->async_tx.elem.out_num = n->async_tx.len = 0;
@@ -754,7 +754,7 @@ static int32_t virtio_net_flush_tx(VirtIONet *n, VirtQueue *vq)
 
         len += ret;
 
-        virtqueue_push(vq, &elem, len);
+        virtqueue_push(vq, &elem, 0);
         virtio_notify(&n->vdev, vq);
 
         if (++num_packets >= n->tx_burst) {

hw/virtio-serial-bus.c

@@ -287,6 +287,7 @@ ssize_t virtio_serial_write(VirtIOSerialPort *port, const uint8_t *buf,
 size_t virtio_serial_guest_ready(VirtIOSerialPort *port)
 {
     VirtQueue *vq = port->ivq;
+    unsigned int bytes;
 
     if (!virtio_queue_ready(vq) ||
         !(port->vser->vdev.status & VIRTIO_CONFIG_S_DRIVER_OK) ||
@@ -296,14 +297,8 @@ size_t virtio_serial_guest_ready(VirtIOSerialPort *port)
     if (use_multiport(port->vser) && !port->guest_connected) {
         return 0;
     }
-
-    if (virtqueue_avail_bytes(vq, 4096, 0)) {
-        return 4096;
-    }
-    if (virtqueue_avail_bytes(vq, 1, 0)) {
-        return 1;
-    }
-    return 0;
+    virtqueue_get_avail_bytes(vq, &bytes, NULL);
+    return bytes;
 }
 
 static void flush_queued_data_bh(void *opaque)

hw/virtio.c

@@ -241,7 +241,7 @@ void virtqueue_fill(VirtQueue *vq, const VirtQueueElement *elem,
                                   elem->in_sg[i].iov_len,
                                   1, size);
 
-        offset += elem->in_sg[i].iov_len;
+        offset += size;
     }
 
     for (i = 0; i < elem->out_num; i++)
@@ -335,10 +335,11 @@ static unsigned virtqueue_next_desc(target_phys_addr_t desc_pa,
     return next;
 }
 
-int virtqueue_avail_bytes(VirtQueue *vq, int in_bytes, int out_bytes)
+void virtqueue_get_avail_bytes(VirtQueue *vq, unsigned int *in_bytes,
+                               unsigned int *out_bytes)
 {
     unsigned int idx;
-    int total_bufs, in_total, out_total;
+    unsigned int total_bufs, in_total, out_total;
 
     idx = vq->last_avail_idx;
 
@@ -380,13 +381,9 @@ int virtqueue_avail_bytes(VirtQueue *vq, int in_bytes, int out_bytes)
             }
 
             if (vring_desc_flags(desc_pa, i) & VRING_DESC_F_WRITE) {
-                if (in_bytes > 0 &&
-                    (in_total += vring_desc_len(desc_pa, i)) >= in_bytes)
-                    return 1;
+                in_total += vring_desc_len(desc_pa, i);
             } else {
-                if (out_bytes > 0 &&
-                    (out_total += vring_desc_len(desc_pa, i)) >= out_bytes)
-                    return 1;
+                out_total += vring_desc_len(desc_pa, i);
             }
         } while ((i = virtqueue_next_desc(desc_pa, i, max)) != max);
 
@@ -395,7 +392,24 @@ int virtqueue_avail_bytes(VirtQueue *vq, int in_bytes, int out_bytes)
         else
             total_bufs++;
     }
+    if (in_bytes) {
+        *in_bytes = in_total;
+    }
+    if (out_bytes) {
+        *out_bytes = out_total;
+    }
+}
 
+int virtqueue_avail_bytes(VirtQueue *vq, unsigned int in_bytes,
+                          unsigned int out_bytes)
+{
+    unsigned int in_total, out_total;
+
+    virtqueue_get_avail_bytes(vq, &in_total, &out_total);
+    if ((in_bytes && in_bytes < in_total)
+        || (out_bytes && out_bytes < out_total)) {
+        return 1;
+    }
     return 0;
 }
 

hw/virtio.h

@@ -147,7 +147,10 @@ void virtqueue_fill(VirtQueue *vq, const VirtQueueElement *elem,
 void virtqueue_map_sg(struct iovec *sg, target_phys_addr_t *addr,
     size_t num_sg, int is_write);
 int virtqueue_pop(VirtQueue *vq, VirtQueueElement *elem);
-int virtqueue_avail_bytes(VirtQueue *vq, int in_bytes, int out_bytes);
+int virtqueue_avail_bytes(VirtQueue *vq, unsigned int in_bytes,
+                          unsigned int out_bytes);
+void virtqueue_get_avail_bytes(VirtQueue *vq, unsigned int *in_bytes,
+                               unsigned int *out_bytes);
 
 void virtio_notify(VirtIODevice *vdev, VirtQueue *vq);
 

iov.c

@@ -26,7 +26,7 @@
 # include <sys/socket.h>
 #endif
 
-size_t iov_from_buf(struct iovec *iov, unsigned int iov_cnt,
+size_t iov_from_buf(const struct iovec *iov, unsigned int iov_cnt,
                     size_t offset, const void *buf, size_t bytes)
 {
     size_t done;

iov.h

@@ -36,7 +36,7 @@ size_t iov_size(const struct iovec *iov, const unsigned int iov_cnt);
  * such "large" value is -1 (sinice size_t is unsigned),
  * so specifying `-1' as `bytes' means 'up to the end of iovec'.
  */
-size_t iov_from_buf(struct iovec *iov, unsigned int iov_cnt,
+size_t iov_from_buf(const struct iovec *iov, unsigned int iov_cnt,
                     size_t offset, const void *buf, size_t bytes);
 size_t iov_to_buf(const struct iovec *iov, const unsigned int iov_cnt,
                   size_t offset, void *buf, size_t bytes);