Commit 96d4c588 authored by David Vrabel's avatar David Vrabel Committed by Konrad Rzeszutek Wilk
Browse files

xen/events: allow setup of irq_info to fail 



The FIFO-based event ABI requires additional setup of newly bound
events (it may need to expand the event array) and this setup may
fail.

xen_irq_info_common_init() is a useful place to put this setup so
allow this call to fail.  This call and the other similar calls are
renamed to be *_setup() to reflect that they may now fail.

This failure can only occur with new event channels not on rebind.

Signed-off-by: default avatarDavid Vrabel <david.vrabel@citrix.com>
Reviewed-by: default avatarKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: default avatarBoris Ostrovsky <boris.ostrovsky@oracle.com>
parent ab9a1cca

drivers/xen/events/events_base.c

+91 −65
Original line number Diff line number Diff line
@@ -99,7 +99,7 @@ struct irq_info *info_for_irq(unsigned irq) 
}



/* Constructors for packed IRQ information. */

static void xen_irq_info_common_init(struct irq_info *info,

static int xen_irq_info_common_setup(struct irq_info *info,

				     unsigned irq,

				     enum xen_irq_type type,

				     unsigned short evtchn,
@@ -116,45 +116,47 @@ static void xen_irq_info_common_init(struct irq_info *info, 
	evtchn_to_irq[evtchn] = irq;



	irq_clear_status_flags(irq, IRQ_NOREQUEST|IRQ_NOAUTOEN);



	return 0;

}



static void xen_irq_info_evtchn_init(unsigned irq,

static int xen_irq_info_evtchn_setup(unsigned irq,

				     unsigned short evtchn)

{

	struct irq_info *info = info_for_irq(irq);



	xen_irq_info_common_init(info, irq, IRQT_EVTCHN, evtchn, 0);

	return xen_irq_info_common_setup(info, irq, IRQT_EVTCHN, evtchn, 0);

}



static void xen_irq_info_ipi_init(unsigned cpu,

static int xen_irq_info_ipi_setup(unsigned cpu,

				  unsigned irq,

				  unsigned short evtchn,

				  enum ipi_vector ipi)

{

	struct irq_info *info = info_for_irq(irq);



	xen_irq_info_common_init(info, irq, IRQT_IPI, evtchn, 0);



	info->u.ipi = ipi;



	per_cpu(ipi_to_irq, cpu)[ipi] = irq;



	return xen_irq_info_common_setup(info, irq, IRQT_IPI, evtchn, 0);

}



static void xen_irq_info_virq_init(unsigned cpu,

static int xen_irq_info_virq_setup(unsigned cpu,

				   unsigned irq,

				   unsigned short evtchn,

				   unsigned short virq)

{

	struct irq_info *info = info_for_irq(irq);



	xen_irq_info_common_init(info, irq, IRQT_VIRQ, evtchn, 0);



	info->u.virq = virq;



	per_cpu(virq_to_irq, cpu)[virq] = irq;



	return xen_irq_info_common_setup(info, irq, IRQT_VIRQ, evtchn, 0);

}



static void xen_irq_info_pirq_init(unsigned irq,

static int xen_irq_info_pirq_setup(unsigned irq,

				   unsigned short evtchn,

				   unsigned short pirq,

				   unsigned short gsi,
@@ -163,12 +165,12 @@ static void xen_irq_info_pirq_init(unsigned irq, 
{

	struct irq_info *info = info_for_irq(irq);



	xen_irq_info_common_init(info, irq, IRQT_PIRQ, evtchn, 0);



	info->u.pirq.pirq = pirq;

	info->u.pirq.gsi = gsi;

	info->u.pirq.domid = domid;

	info->u.pirq.flags = flags;



	return xen_irq_info_common_setup(info, irq, IRQT_PIRQ, evtchn, 0);

}



/*
@@ -521,6 +523,47 @@ int xen_irq_from_gsi(unsigned gsi) 
}

EXPORT_SYMBOL_GPL(xen_irq_from_gsi);



static void __unbind_from_irq(unsigned int irq)

{

	struct evtchn_close close;

	int evtchn = evtchn_from_irq(irq);

	struct irq_info *info = irq_get_handler_data(irq);



	if (info->refcnt > 0) {

		info->refcnt--;

		if (info->refcnt != 0)

			return;

	}



	if (VALID_EVTCHN(evtchn)) {

		close.port = evtchn;

		if (HYPERVISOR_event_channel_op(EVTCHNOP_close, &close) != 0)

			BUG();



		switch (type_from_irq(irq)) {

		case IRQT_VIRQ:

			per_cpu(virq_to_irq, cpu_from_evtchn(evtchn))

				[virq_from_irq(irq)] = -1;

			break;

		case IRQT_IPI:

			per_cpu(ipi_to_irq, cpu_from_evtchn(evtchn))

				[ipi_from_irq(irq)] = -1;

			break;

		default:

			break;

		}



		/* Closed ports are implicitly re-bound to VCPU0. */

		bind_evtchn_to_cpu(evtchn, 0);



		evtchn_to_irq[evtchn] = -1;

	}



	BUG_ON(info_for_irq(irq)->type == IRQT_UNBOUND);



	xen_free_irq(irq);

}



/*

 * Do not make any assumptions regarding the relationship between the

 * IRQ number returned here and the Xen pirq argument.
@@ -536,6 +579,7 @@ int xen_bind_pirq_gsi_to_irq(unsigned gsi, 
{

	int irq = -1;

	struct physdev_irq irq_op;

	int ret;



	mutex_lock(&irq_mapping_update_lock);
@@ -563,8 +607,13 @@ int xen_bind_pirq_gsi_to_irq(unsigned gsi, 
		goto out;

	}



	xen_irq_info_pirq_init(irq, 0, pirq, gsi, DOMID_SELF,

	ret = xen_irq_info_pirq_setup(irq, 0, pirq, gsi, DOMID_SELF,

			       shareable ? PIRQ_SHAREABLE : 0);

	if (ret < 0) {

		__unbind_from_irq(irq);

		irq = ret;

		goto out;

	}



	pirq_query_unmask(irq);

	/* We try to use the handler with the appropriate semantic for the
@@ -624,7 +673,9 @@ int xen_bind_pirq_msi_to_irq(struct pci_dev *dev, struct msi_desc *msidesc, 
	irq_set_chip_and_handler_name(irq, &xen_pirq_chip, handle_edge_irq,

			name);



	xen_irq_info_pirq_init(irq, 0, pirq, 0, domid, 0);

	ret = xen_irq_info_pirq_setup(irq, 0, pirq, 0, domid, 0);

	if (ret < 0)

		goto error_irq;

	ret = irq_set_msi_desc(irq, msidesc);

	if (ret < 0)

		goto error_irq;
@@ -632,8 +683,8 @@ out: 
	mutex_unlock(&irq_mapping_update_lock);

	return irq;

error_irq:

	__unbind_from_irq(irq);

	mutex_unlock(&irq_mapping_update_lock);

	xen_free_irq(irq);

	return ret;

}

#endif
@@ -703,9 +754,11 @@ int xen_pirq_from_irq(unsigned irq) 
	return pirq_from_irq(irq);

}

EXPORT_SYMBOL_GPL(xen_pirq_from_irq);



int bind_evtchn_to_irq(unsigned int evtchn)

{

	int irq;

	int ret;



	mutex_lock(&irq_mapping_update_lock);
@@ -719,7 +772,12 @@ int bind_evtchn_to_irq(unsigned int evtchn) 
		irq_set_chip_and_handler_name(irq, &xen_dynamic_chip,

					      handle_edge_irq, "event");



		xen_irq_info_evtchn_init(irq, evtchn);

		ret = xen_irq_info_evtchn_setup(irq, evtchn);

		if (ret < 0) {

			__unbind_from_irq(irq);

			irq = ret;

			goto out;

		}

	} else {

		struct irq_info *info = info_for_irq(irq);

		WARN_ON(info == NULL || info->type != IRQT_EVTCHN);
@@ -736,6 +794,7 @@ static int bind_ipi_to_irq(unsigned int ipi, unsigned int cpu) 
{

	struct evtchn_bind_ipi bind_ipi;

	int evtchn, irq;

	int ret;



	mutex_lock(&irq_mapping_update_lock);
@@ -755,8 +814,12 @@ static int bind_ipi_to_irq(unsigned int ipi, unsigned int cpu) 
			BUG();

		evtchn = bind_ipi.port;



		xen_irq_info_ipi_init(cpu, irq, evtchn, ipi);



		ret = xen_irq_info_ipi_setup(cpu, irq, evtchn, ipi);

		if (ret < 0) {

			__unbind_from_irq(irq);

			irq = ret;

			goto out;

		}

		bind_evtchn_to_cpu(evtchn, cpu);

	} else {

		struct irq_info *info = info_for_irq(irq);
@@ -835,7 +898,12 @@ int bind_virq_to_irq(unsigned int virq, unsigned int cpu) 
			evtchn = ret;

		}



		xen_irq_info_virq_init(cpu, irq, evtchn, virq);

		ret = xen_irq_info_virq_setup(cpu, irq, evtchn, virq);

		if (ret < 0) {

			__unbind_from_irq(irq);

			irq = ret;

			goto out;

		}



		bind_evtchn_to_cpu(evtchn, cpu);

	} else {
@@ -851,50 +919,8 @@ out: 


static void unbind_from_irq(unsigned int irq)

{

	struct evtchn_close close;

	int evtchn = evtchn_from_irq(irq);

	struct irq_info *info = irq_get_handler_data(irq);



	if (WARN_ON(!info))

		return;



	mutex_lock(&irq_mapping_update_lock);



	if (info->refcnt > 0) {

		info->refcnt--;

		if (info->refcnt != 0)

			goto done;

	}



	if (VALID_EVTCHN(evtchn)) {

		close.port = evtchn;

		if (HYPERVISOR_event_channel_op(EVTCHNOP_close, &close) != 0)

			BUG();



		switch (type_from_irq(irq)) {

		case IRQT_VIRQ:

			per_cpu(virq_to_irq, cpu_from_evtchn(evtchn))

				[virq_from_irq(irq)] = -1;

			break;

		case IRQT_IPI:

			per_cpu(ipi_to_irq, cpu_from_evtchn(evtchn))

				[ipi_from_irq(irq)] = -1;

			break;

		default:

			break;

		}



		/* Closed ports are implicitly re-bound to VCPU0. */

		bind_evtchn_to_cpu(evtchn, 0);



		evtchn_to_irq[evtchn] = -1;

	}



	BUG_ON(info_for_irq(irq)->type == IRQT_UNBOUND);



	xen_free_irq(irq);



 done:

	__unbind_from_irq(irq);

	mutex_unlock(&irq_mapping_update_lock);

}
@@ -1142,7 +1168,7 @@ void rebind_evtchn_irq(int evtchn, int irq) 
	   so there should be a proper type */

	BUG_ON(info->type == IRQT_UNBOUND);



	xen_irq_info_evtchn_init(irq, evtchn);

	(void)xen_irq_info_evtchn_setup(irq, evtchn);



	mutex_unlock(&irq_mapping_update_lock);
@@ -1317,7 +1343,7 @@ static void restore_cpu_virqs(unsigned int cpu) 
		evtchn = bind_virq.port;



		/* Record the new mapping. */

		xen_irq_info_virq_init(cpu, irq, evtchn, virq);

		(void)xen_irq_info_virq_setup(cpu, irq, evtchn, virq);

		bind_evtchn_to_cpu(evtchn, cpu);

	}

}
@@ -1341,7 +1367,7 @@ static void restore_cpu_ipis(unsigned int cpu) 
		evtchn = bind_ipi.port;



		/* Record the new mapping. */

		xen_irq_info_ipi_init(cpu, irq, evtchn, ipi);

		(void)xen_irq_info_ipi_setup(cpu, irq, evtchn, ipi);

		bind_evtchn_to_cpu(evtchn, cpu);

	}

}

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