Commit cf8e019b authored by Stefano Stabellini's avatar Stefano Stabellini Committed by Konrad Rzeszutek Wilk
Browse files

hvc_xen: introduce HVC_XEN_FRONTEND 



Introduce a new config option HVC_XEN_FRONTEND to enable/disable the
xenbus based pv console frontend.

Signed-off-by: default avatarStefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: default avatarKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
parent 02e19f9c

drivers/tty/hvc/Kconfig

+8 −0
Original line number Diff line number Diff line
@@ -76,6 +76,14 @@ config HVC_XEN 
	help

	  Xen virtual console device driver



config HVC_XEN_FRONTEND

	bool "Xen Hypervisor Multiple Consoles support"

	depends on HVC_XEN

	select XEN_XENBUS_FRONTEND

	default y

	help

	  Xen driver for secondary virtual consoles



config HVC_UDBG

       bool "udbg based fake hypervisor console"

       depends on PPC && EXPERIMENTAL

drivers/tty/hvc/hvc_xen.c

+62 −54
Original line number Diff line number Diff line
@@ -55,7 +55,6 @@ struct xencons_info { 


static LIST_HEAD(xenconsoles);

static DEFINE_SPINLOCK(xencons_lock);

static struct xenbus_driver xencons_driver;



/* ------------------------------------------------------------------ */
@@ -298,53 +297,6 @@ static int xen_initial_domain_console_init(void) 
	return 0;

}



static int __init xen_hvc_init(void)

{

	int r;

	struct xencons_info *info;

	const struct hv_ops *ops;



	if (!xen_domain())

		return -ENODEV;



	if (xen_initial_domain()) {

		ops = &dom0_hvc_ops;

		r = xen_initial_domain_console_init();

		if (r < 0)

			return r;

		info = vtermno_to_xencons(HVC_COOKIE);

	} else {

		ops = &domU_hvc_ops;

		if (xen_hvm_domain())

			r = xen_hvm_console_init();

		else

			r = xen_pv_console_init();

		if (r < 0)

			return r;



		info = vtermno_to_xencons(HVC_COOKIE);

		info->irq = bind_evtchn_to_irq(info->evtchn);

	}

	if (info->irq < 0)

		info->irq = 0; /* NO_IRQ */

	else

		irq_set_noprobe(info->irq);



	info->hvc = hvc_alloc(HVC_COOKIE, info->irq, ops, 256);

	if (IS_ERR(info->hvc)) {

		r = PTR_ERR(info->hvc);

		spin_lock(&xencons_lock);

		list_del(&info->list);

		spin_unlock(&xencons_lock);

		if (info->irq)

			unbind_from_irqhandler(info->irq, NULL);

		kfree(info);

		return r;

	}



	return xenbus_register_frontend(&xencons_driver);

}



void xen_console_resume(void)

{

	struct xencons_info *info = vtermno_to_xencons(HVC_COOKIE);
@@ -392,6 +344,9 @@ static int xen_console_remove(struct xencons_info *info) 
	return 0;

}



#ifdef CONFIG_HVC_XEN_FRONTEND

static struct xenbus_driver xencons_driver;



static int xencons_remove(struct xenbus_device *dev)

{

	return xen_console_remove(dev_get_drvdata(&dev->dev));
@@ -543,6 +498,65 @@ static const struct xenbus_device_id xencons_ids[] = { 
};





static DEFINE_XENBUS_DRIVER(xencons, "xenconsole",

	.probe = xencons_probe,

	.remove = xencons_remove,

	.resume = xencons_resume,

	.otherend_changed = xencons_backend_changed,

);

#endif /* CONFIG_HVC_XEN_FRONTEND */



static int __init xen_hvc_init(void)

{

	int r;

	struct xencons_info *info;

	const struct hv_ops *ops;



	if (!xen_domain())

		return -ENODEV;



	if (xen_initial_domain()) {

		ops = &dom0_hvc_ops;

		r = xen_initial_domain_console_init();

		if (r < 0)

			return r;

		info = vtermno_to_xencons(HVC_COOKIE);

	} else {

		ops = &domU_hvc_ops;

		if (xen_hvm_domain())

			r = xen_hvm_console_init();

		else

			r = xen_pv_console_init();

		if (r < 0)

			return r;



		info = vtermno_to_xencons(HVC_COOKIE);

		info->irq = bind_evtchn_to_irq(info->evtchn);

	}

	if (info->irq < 0)

		info->irq = 0; /* NO_IRQ */

	else

		irq_set_noprobe(info->irq);



	info->hvc = hvc_alloc(HVC_COOKIE, info->irq, ops, 256);

	if (IS_ERR(info->hvc)) {

		r = PTR_ERR(info->hvc);

		spin_lock(&xencons_lock);

		list_del(&info->list);

		spin_unlock(&xencons_lock);

		if (info->irq)

			unbind_from_irqhandler(info->irq, NULL);

		kfree(info);

		return r;

	}



	r = 0;

#ifdef CONFIG_HVC_XEN_FRONTEND

	r = xenbus_register_frontend(&xencons_driver);

#endif

	return r;

}



static void __exit xen_hvc_fini(void)

{

	struct xencons_info *entry, *next;
@@ -580,12 +594,6 @@ static int xen_cons_init(void) 
	return 0;

}



static DEFINE_XENBUS_DRIVER(xencons, "xenconsole",

	.probe = xencons_probe,

	.remove = xencons_remove,

	.resume = xencons_resume,

	.otherend_changed = xencons_backend_changed,

);



module_init(xen_hvc_init);

module_exit(xen_hvc_fini);