virtio: console: Associate each port with a char device (fb08bd27) · Commits · 戴 / test

drivers/char/Kconfig

+8 −0

Original line number	Diff line number	Diff line
		@@ -666,6 +666,14 @@ config VIRTIO_CONSOLE
		help
		Virtio console for use with lguest and other hypervisors.

		Also serves as a general-purpose serial device for data
		transfer between the guest and host. Character devices at
		/dev/vportNpn will be created when corresponding ports are
		found, where N is the device number and n is the port number
		within that device. If specified by the host, a sysfs
		attribute called 'name' will be populated with a name for
		the port which can be used by udev scripts to create a
		symlink to the device.

		config HVCS
		tristate "IBM Hypervisor Virtual Console Server support"

drivers/char/virtio_console.c

+74 −7

Original line number	Diff line number	Diff line
		@@ -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
		@@ -116,6 +124,12 @@ struct ports_device {

		/* Array of per-port IO virtqueues */
		struct virtqueue in_vqs, out_vqs;

		/* 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 the per-port data */
		@@ -145,6 +159,10 @@ struct port {
		*/
		struct console cons;

		/* Each port associates with a separate char device */
		struct cdev cdev;
		struct device *dev;

		/* The 'id' to identify the port with the Host */
		u32 id;
		};
		@@ -391,7 +409,7 @@ static ssize_t fill_readbuf(struct port port, char out_buf, size_t out_count,
		port->inbuf = NULL;

		if (add_inbuf(port->in_vq, buf) < 0)
		dev_warn(&port->portdev->vdev->dev, "failed add_buf\n");
		dev_warn(port->dev, "failed add_buf\n");

		spin_unlock_irqrestore(&port->inbuf_lock, flags);
		}
		@@ -664,6 +682,7 @@ static int add_port(struct ports_device *portdev, u32 id)
		{
		struct port *port;
		struct port_buffer *inbuf;
		dev_t devt;
		int err;

		port = kmalloc(sizeof(*port), GFP_KERNEL);
		@@ -681,12 +700,32 @@ static int add_port(struct ports_device *portdev, u32 id)
		port->in_vq = portdev->in_vqs[port->id];
		port->out_vq = portdev->out_vqs[port->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->inbuf_lock);

		inbuf = alloc_buf(PAGE_SIZE);
		if (!inbuf) {
		err = -ENOMEM;
		goto free_port;
		goto free_device;
		}

		/* Register the input buffer the first time. */
		@@ -716,6 +755,10 @@ static int add_port(struct ports_device *portdev, u32 id)

		free_inbuf:
		free_buf(inbuf);
		free_device:
		device_destroy(pdrvdata.class, port->dev->devt);
		free_cdev:
		cdev_del(&port->cdev);
		free_port:
		kfree(port);
		fail:
		@@ -828,6 +871,10 @@ fail:
		return err;
		}

		static const struct file_operations portdev_fops = {
		.owner = THIS_MODULE,
		};

		/*
		* Once we're further in boot, we get probed like any other virtio
		* device.
		@@ -853,6 +900,20 @@ 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);
		err = portdev->chr_major;
		goto free;
		}

		multiport = false;
		portdev->config.nr_ports = 1;
		portdev->config.max_nr_ports = 1;
		@@ -885,7 +946,7 @@ static int __devinit virtcons_probe(struct virtio_device *vdev)
		err = init_vqs(portdev);
		if (err < 0) {
		dev_err(&vdev->dev, "Error %d initializing vqs\n", err);
		goto free;
		goto free_chrdev;
		}

		spin_lock_init(&portdev->ports_lock);
		@@ -905,10 +966,8 @@ static int __devinit virtcons_probe(struct virtio_device *vdev)
		early_put_chars = NULL;
		return 0;

		free_vqs:
		vdev->config->del_vqs(vdev);
		kfree(portdev->in_vqs);
		kfree(portdev->out_vqs);
		free_chrdev:
		unregister_chrdev(portdev->chr_major, "virtio-portsdev");
		free:
		kfree(portdev);
		fail:
		@@ -937,6 +996,14 @@ 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);

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