Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging-2.6

[linux-2.6-block.git] / drivers / char / virtio_console.c

diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c
index f404ccfc9c20992f342eb366dd21231642d078ea..196428c2287a453b6259beff3cefd591199e6071 100644 (file)
--- 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 = {