1 files changed, 24 insertions, 0 deletions

diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c
index 105181c1e6be..387fcdf019b7 100644
--- a/drivers/char/virtio_console.c
+++ b/drivers/char/virtio_console.c
@@ -152,6 +152,10 @@ struct ports_device {
         int chr_major;
 };
 
+struct port_stats {
+        unsigned long bytes_sent, bytes_received, bytes_discarded;
+};
+
 /* This struct holds the per-port data */
 struct port {
         /* Next port in the list, head is in the ports_device */
@@ -180,6 +184,13 @@ struct port {
         struct dentry *debugfs_file;
 
         /*
+         * Keep count of the bytes sent, received and discarded for
+         * this port for accounting and debugging purposes.  These
+         * counts are not reset across port open / close events.
+         */
+        struct port_stats stats;
+
+        /*
          * The entries in this struct will be valid if this port is
          * hooked up to an hvc console
          */
@@ -360,6 +371,7 @@ static struct port_buffer *get_inbuf(struct port *port)
         if (buf) {
                 buf->len = len;
                 buf->offset = 0;
+                port->stats.bytes_received += len;
         }
         return buf;
 }
@@ -396,6 +408,7 @@ static void discard_port_data(struct port *port)
 
         err = 0;
         while (buf) {
+                port->stats.bytes_discarded += buf->len - buf->offset;
                 if (add_inbuf(port->in_vq, buf) < 0) {
                         err++;
                         free_buf(buf);
@@ -519,6 +532,8 @@ static ssize_t send_buf(struct port *port, void *in_buf, size_t in_count,
                 cpu_relax();
 done:
         spin_unlock_irqrestore(&port->outvq_lock, flags);
+
+        port->stats.bytes_sent += in_count;
         /*
          * We're expected to return the amount of data we wrote -- all
          * of it
@@ -1049,6 +1064,14 @@ static ssize_t debugfs_read(struct file *filp, char __user *ubuf,
         out_offset += snprintf(buf + out_offset, out_count - out_offset,
                                "outvq_full: %d\n", port->outvq_full);
         out_offset += snprintf(buf + out_offset, out_count - out_offset,
+                               "bytes_sent: %lu\n", port->stats.bytes_sent);
+        out_offset += snprintf(buf + out_offset, out_count - out_offset,
+                               "bytes_received: %lu\n",
+                               port->stats.bytes_received);
+        out_offset += snprintf(buf + out_offset, out_count - out_offset,
+                               "bytes_discarded: %lu\n",
+                               port->stats.bytes_discarded);
+        out_offset += snprintf(buf + out_offset, out_count - out_offset,
                                "is_console: %s\n",
                                is_console_port(port) ? "yes" : "no");
         out_offset += snprintf(buf + out_offset, out_count - out_offset,
@@ -1133,6 +1156,7 @@ static int add_port(struct ports_device *portdev, u32 id)
         port->cons.ws.ws_row = port->cons.ws.ws_col = 0;
 
         port->host_connected = port->guest_connected = false;
+        port->stats = (struct port_stats) { 0 };
 
         port->outvq_full = false;