rpmsg: process _all_ pending messages in rpmsg_recv_done

Change virtqueue callback function rpmsg_recv_done() to process all
available messages instead of just one message.

Signed-off-by: Robert Tivy <rtivy@ti.com>
[split _recv function instead of adding indentation]
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>

1 files changed, 35 insertions, 14 deletions

diff --git a/drivers/rpmsg/virtio_rpmsg_bus.c b/drivers/rpmsg/virtio_rpmsg_bus.c
index a59684b5fc68..07d5ea2ac77a 100644
--- a/drivers/rpmsg/virtio_rpmsg_bus.c
+++ b/drivers/rpmsg/virtio_rpmsg_bus.c
@@ -776,23 +776,13 @@ out:
 }
 EXPORT_SYMBOL(rpmsg_send_offchannel_raw);
 
-/* called when an rx buffer is used, and it's time to digest a message */
-static void rpmsg_recv_done(struct virtqueue *rvq)
+static int rpmsg_recv_single(struct virtproc_info *vrp, struct device *dev,
+                             struct rpmsg_hdr *msg, unsigned int len)
 {
-        struct rpmsg_hdr *msg;
-        unsigned int len;
         struct rpmsg_endpoint *ept;
         struct scatterlist sg;
-        struct virtproc_info *vrp = rvq->vdev->priv;
-        struct device *dev = &rvq->vdev->dev;
         int err;
 
-        msg = virtqueue_get_buf(rvq, &len);
-        if (!msg) {
-                dev_err(dev, "uhm, incoming signal, but no used buffer ?\n");
-                return;
-        }
-
         dev_dbg(dev, "From: 0x%x, To: 0x%x, Len: %d, Flags: %d, Reserved: %d\n",
                                         msg->src, msg->dst, msg->len,
                                         msg->flags, msg->reserved);
@@ -806,7 +796,7 @@ static void rpmsg_recv_done(struct virtqueue *rvq)
         if (len > RPMSG_BUF_SIZE ||
                 msg->len > (len - sizeof(struct rpmsg_hdr))) {
                 dev_warn(dev, "inbound msg too big: (%d, %d)\n", len, msg->len);
-                return;
+                return -EINVAL;
         }
 
         /* use the dst addr to fetch the callback of the appropriate user */
@@ -842,11 +832,42 @@ static void rpmsg_recv_done(struct virtqueue *rvq)
         err = virtqueue_add_buf(vrp->rvq, &sg, 0, 1, msg, GFP_KERNEL);
         if (err < 0) {
                 dev_err(dev, "failed to add a virtqueue buffer: %d\n", err);
+                return err;
+        }
+
+        return 0;
+}
+
+/* called when an rx buffer is used, and it's time to digest a message */
+static void rpmsg_recv_done(struct virtqueue *rvq)
+{
+        struct virtproc_info *vrp = rvq->vdev->priv;
+        struct device *dev = &rvq->vdev->dev;
+        struct rpmsg_hdr *msg;
+        unsigned int len, msgs_received = 0;
+        int err;
+
+        msg = virtqueue_get_buf(rvq, &len);
+        if (!msg) {
+                dev_err(dev, "uhm, incoming signal, but no used buffer ?\n");
                 return;
         }
 
+        while (msg) {
+                err = rpmsg_recv_single(vrp, dev, msg, len);
+                if (err)
+                        break;
+
+                msgs_received++;
+
+                msg = virtqueue_get_buf(rvq, &len);
+        };
+
+        dev_dbg(dev, "Received %u messages\n", msgs_received);
+
         /* tell the remote processor we added another available rx buffer */
-        virtqueue_kick(vrp->rvq);
+        if (msgs_received)
+                virtqueue_kick(vrp->rvq);
 }
 
 /*