The char device will be used as an interface by applications on the
guest to communicate with apps on the host.
The devices created are placed in /dev/vportNpn where N is the
virtio-console device number and n is the port number for that device.
The file operation for the char devs will be added in the following
commits.
Signed-off-by: Amit Shah <amit.shah@xxxxxxxxxx>
---
drivers/char/virtio_console.c | 76 +++++++++++++++++++++++++++++++++++++++--
1 files changed, 73 insertions(+), 3 deletions(-)
diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c
index a26781b..56b7cfa 100644
--- a/drivers/char/virtio_console.c
+++ b/drivers/char/virtio_console.c
@@ -16,6 +16,8 @@
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
+#include <linux/cdev.h>
+#include <linux/device.h>
#include <linux/err.h>
#include <linux/init.h>
#include <linux/list.h>
@@ -34,6 +36,12 @@
* across multiple devices and multiple ports per device.
*/
struct ports_driver_data {
+ /* Used for registering chardevs */
+ struct class *class;
+
+ /* Number of devices this driver is handling */
+ unsigned int index;
+
/*
* This is used to keep track of the number of hvc consoles
* spawned by this driver. This number is given as the first
@@ -100,6 +108,12 @@ struct ports_device {
/* The current config space is stored here */
struct virtio_console_config config;
+
+ /* Used for numbering devices for sysfs and debugfs */
+ unsigned int drv_index;
+
+ /* Major number for this device. Ports will be created as minors. */
+ int chr_major;
};
/* This struct holds individual buffers received for each port */
@@ -132,6 +146,10 @@ struct port {
*/
spinlock_t readbuf_list_lock;
+ /* Each port associates with a separate char device */
+ struct cdev cdev;
+ struct device *dev;
+
/*
* The entries in this struct will be valid if this port is
* hooked up to an hvc console
@@ -703,6 +721,7 @@ static void tx_intr(struct virtqueue *vq)
static int __devinit add_port(struct ports_device *portdev, u32 id)
{
struct port *port;
+ dev_t devt;
int err;
err = -ENOMEM;
@@ -713,6 +732,25 @@ static int __devinit add_port(struct ports_device *portdev, u32 id)
port->portdev = portdev;
port->id = id;
+ cdev_init(&port->cdev, NULL);
+
+ devt = MKDEV(portdev->chr_major, id);
+ err = cdev_add(&port->cdev, devt, 1);
+ if (err < 0) {
+ dev_err(&port->portdev->vdev->dev,
+ "error %d adding cdev for port %u\n", err, id);
+ goto free_port;
+ }
+ port->dev = device_create(pdrvdata.class, &port->portdev->vdev->dev,
+ devt, port, "vport%up%u",
+ port->portdev->drv_index, id);
+ if (IS_ERR(port->dev)) {
+ err = PTR_ERR(port->dev);
+ dev_err(&port->portdev->vdev->dev,
+ "error %d creating device for port %u\n",
+ err, id);
+ goto free_cdev;
+ }
spin_lock_init(&port->readbuf_list_lock);
INIT_LIST_HEAD(&port->readbuf_head);
@@ -722,7 +760,7 @@ static int __devinit add_port(struct ports_device *portdev, u32 id)
if (!use_multiport(port->portdev)) {
err = init_port_console(port);
if (err)
- goto free;
+ goto free_device;
}
spin_lock_irq(&portdev->ports_list_lock);
list_add_tail(&port->list, &port->portdev->ports_head);
@@ -737,12 +775,21 @@ static int __devinit add_port(struct ports_device *portdev, u32 id)
send_control_msg(port, VIRTIO_CONSOLE_PORT_READY, 1);
return 0;
-free:
+
+free_device:
+ device_destroy(pdrvdata.class, port->dev->devt);
+free_cdev:
+ cdev_del(&port->cdev);
+free_port:
kfree(port);
fail:
return err;
}
+static struct file_operations portdev_fops = {
+ .owner = THIS_MODULE,
+};
+
/*
* Once we're further in boot, we get probed like any other virtio
* device.
@@ -770,6 +817,18 @@ static int __devinit virtcons_probe(struct virtio_device *vdev)
portdev->vdev = vdev;
vdev->priv = portdev;
+ spin_lock_irq(&pdrvdata_lock);
+ portdev->drv_index = pdrvdata.index++;
+ spin_unlock_irq(&pdrvdata_lock);
+
+ portdev->chr_major = register_chrdev(0, "virtio-portsdev",
+ &portdev_fops);
+ if (portdev->chr_major < 0) {
+ dev_err(&vdev->dev,
+ "error %d registering chrdev for device %u\n",
+ portdev->chr_major, portdev->drv_index);
+ goto free;
+ }
multiport = false;
if (virtio_has_feature(vdev, VIRTIO_CONSOLE_F_MULTIPORT)) {
multiport = true;
@@ -785,7 +844,7 @@ static int __devinit virtcons_probe(struct virtio_device *vdev)
/* Find the queues. */
err = vdev->config->find_vqs(vdev, 2, vqs, callbacks, names);
if (err)
- goto free;
+ goto free_chrdev;
portdev->in_vq = vqs[0];
portdev->out_vq = vqs[1];
@@ -812,6 +871,8 @@ static int __devinit virtcons_probe(struct virtio_device *vdev)
early_put_chars = NULL;
return 0;
+free_chrdev:
+ unregister_chrdev(portdev->chr_major, "virtio-portsdev");
free:
kfree(portdev);
fail:
@@ -840,7 +901,16 @@ static struct virtio_driver virtio_console = {
static int __init init(void)
{
+ int err;
+
+ pdrvdata.class = class_create(THIS_MODULE, "virtio-ports");
+ if (IS_ERR(pdrvdata.class)) {
+ err = PTR_ERR(pdrvdata.class);
+ pr_err("Error %d creating virtio-ports class\n", err);
+ return err;
+ }
INIT_LIST_HEAD(&pdrvdata.consoles);
+
return register_virtio_driver(&virtio_console);
}
module_init(init);
--
1.6.2.5
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