1 files changed, 61 insertions, 20 deletions

diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c
index f404ccfc9c20..196428c2287a 100644
--- a/drivers/char/virtio_console.c
+++ b/drivers/char/virtio_console.c
@@ -25,6 +25,7 @@
 #include <linux/list.h>
 #include <linux/poll.h>
 #include <linux/sched.h>
+#include <linux/slab.h>
 #include <linux/spinlock.h>
 #include <linux/virtio.h>
 #include <linux/virtio_console.h>
@@ -32,6 +33,35 @@
 #include <linux/workqueue.h>
 #include "hvc_console.h"
 
+/* Moved here from .h file in order to disable MULTIPORT. */
+#define VIRTIO_CONSOLE_F_MULTIPORT 1    /* Does host provide multiple ports? */
+
+struct virtio_console_multiport_conf {
+        struct virtio_console_config config;
+        /* max. number of ports this device can hold */
+        __u32 max_nr_ports;
+        /* number of ports added so far */
+        __u32 nr_ports;
+} __attribute__((packed));
+
+/*
+ * A message that's passed between the Host and the Guest for a
+ * particular port.
+ */
+struct virtio_console_control {
+        __u32 id;               /* Port number */
+        __u16 event;            /* The kind of control event (see below) */
+        __u16 value;            /* Extra information for the key */
+};
+
+/* Some events for control messages */
+#define VIRTIO_CONSOLE_PORT_READY       0
+#define VIRTIO_CONSOLE_CONSOLE_PORT     1
+#define VIRTIO_CONSOLE_RESIZE           2
+#define VIRTIO_CONSOLE_PORT_OPEN        3
+#define VIRTIO_CONSOLE_PORT_NAME        4
+#define VIRTIO_CONSOLE_PORT_REMOVE      5
+
 /*
  * This is a global struct for storing common data for all the devices
  * this driver handles.
@@ -120,7 +150,7 @@ struct ports_device {
         spinlock_t cvq_lock;
 
         /* The current config space is stored here */
-        struct virtio_console_config config;
+        struct virtio_console_multiport_conf config;
 
         /* The virtio device we're associated with */
         struct virtio_device *vdev;
@@ -415,20 +445,16 @@ static ssize_t send_buf(struct port *port, void *in_buf, size_t in_count)
         out_vq->vq_ops->kick(out_vq);
 
         if (ret < 0) {
-                len = 0;
+                in_count = 0;
                 goto fail;
         }
 
-        /*
-         * Wait till the host acknowledges it pushed out the data we
-         * sent. Also ensure we return to userspace the number of
-         * bytes that were successfully consumed by the host.
-         */
+        /* Wait till the host acknowledges it pushed out the data we sent. */
         while (!out_vq->vq_ops->get_buf(out_vq, &len))
                 cpu_relax();
 fail:
         /* We're expected to return the amount of data we wrote */
-        return len;
+        return in_count;
 }
 
 /*
@@ -645,13 +671,13 @@ static int put_chars(u32 vtermno, const char *buf, int count)
 {
         struct port *port;
 
+        if (unlikely(early_put_chars))
+                return early_put_chars(vtermno, buf, count);
+
         port = find_port_by_vtermno(vtermno);
         if (!port)
                 return 0;
 
-        if (unlikely(early_put_chars))
-                return early_put_chars(vtermno, buf, count);
-
         return send_buf(port, (void *)buf, count);
 }
 
@@ -681,6 +707,10 @@ static void resize_console(struct port *port)
         struct virtio_device *vdev;
         struct winsize ws;
 
+        /* The port could have been hot-unplugged */
+        if (!port)
+                return;
+
         vdev = port->portdev->vdev;
         if (virtio_has_feature(vdev, VIRTIO_CONSOLE_F_SIZE)) {
                 vdev->config->get(vdev,
@@ -947,11 +977,18 @@ static void handle_control_message(struct ports_device *portdev,
                  */
                 err = sysfs_create_group(&port->dev->kobj,
                                          &port_attribute_group);
-                if (err)
+                if (err) {
                         dev_err(port->dev,
                                 "Error %d creating sysfs device attributes\n",
                                 err);
-
+                } else {
+                        /*
+                         * Generate a udev event so that appropriate
+                         * symlinks can be created based on udev
+                         * rules.
+                         */
+                        kobject_uevent(&port->dev->kobj, KOBJ_CHANGE);
+                }
                 break;
         case VIRTIO_CONSOLE_PORT_REMOVE:
                 /*
@@ -1206,7 +1243,7 @@ fail:
  */
 static void config_work_handler(struct work_struct *work)
 {
-        struct virtio_console_config virtconconf;
+        struct virtio_console_multiport_conf virtconconf;
         struct ports_device *portdev;
         struct virtio_device *vdev;
         int err;
@@ -1215,7 +1252,8 @@ static void config_work_handler(struct work_struct *work)
 
         vdev = portdev->vdev;
         vdev->config->get(vdev,
-                          offsetof(struct virtio_console_config, nr_ports),
+                          offsetof(struct virtio_console_multiport_conf,
+                                   nr_ports),
                           &virtconconf.nr_ports,
                           sizeof(virtconconf.nr_ports));
 
@@ -1407,16 +1445,19 @@ static int __devinit virtcons_probe(struct virtio_device *vdev)
         multiport = false;
         portdev->config.nr_ports = 1;
         portdev->config.max_nr_ports = 1;
+#if 0 /* Multiport is not quite ready yet --RR */
         if (virtio_has_feature(vdev, VIRTIO_CONSOLE_F_MULTIPORT)) {
                 multiport = true;
                 vdev->features[0] |= 1 << VIRTIO_CONSOLE_F_MULTIPORT;
 
-                vdev->config->get(vdev, offsetof(struct virtio_console_config,
-                                                 nr_ports),
+                vdev->config->get(vdev,
+                                  offsetof(struct virtio_console_multiport_conf,
+                                           nr_ports),
                                   &portdev->config.nr_ports,
                                   sizeof(portdev->config.nr_ports));
-                vdev->config->get(vdev, offsetof(struct virtio_console_config,
-                                                 max_nr_ports),
+                vdev->config->get(vdev,
+                                  offsetof(struct virtio_console_multiport_conf,
+                                           max_nr_ports),
                                   &portdev->config.max_nr_ports,
                                   sizeof(portdev->config.max_nr_ports));
                 if (portdev->config.nr_ports > portdev->config.max_nr_ports) {
@@ -1432,6 +1473,7 @@ static int __devinit virtcons_probe(struct virtio_device *vdev)
 
         /* Let the Host know we support multiple ports.*/
         vdev->config->finalize_features(vdev);
+#endif
 
         err = init_vqs(portdev);
         if (err < 0) {
@@ -1514,7 +1556,6 @@ static struct virtio_device_id id_table[] = {
 
 static unsigned int features[] = {
         VIRTIO_CONSOLE_F_SIZE,
-        VIRTIO_CONSOLE_F_MULTIPORT,
 };
 
 static struct virtio_driver virtio_console = {