Commit 7a043f11 authored by Stefano Stabellini's avatar Stefano Stabellini
Browse files

xen: support pirq != irq 



PHYSDEVOP_map_pirq might return a pirq different from what we asked if
we are running as an HVM guest, so we need to be able to support pirqs
that are different from linux irqs.

Signed-off-by: default avatarStefano Stabellini <stefano.stabellini@eu.citrix.com>
Reviewed-by: default avatarKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
parent 67ba3729

drivers/xen/events.c

+48 −16
Original line number Diff line number Diff line
@@ -90,6 +90,7 @@ struct irq_info 
		unsigned short virq;

		enum ipi_vector ipi;

		struct {

			unsigned short pirq;

			unsigned short gsi;

			unsigned char vector;

			unsigned char flags;
@@ -100,6 +101,7 @@ struct irq_info 
#define PIRQ_SHAREABLE	(1 << 1)



static struct irq_info *irq_info;

static int *pirq_to_irq;



static int *evtchn_to_irq;

struct cpu_evtchn_s {
@@ -147,11 +149,12 @@ static struct irq_info mk_virq_info(unsigned short evtchn, unsigned short virq) 
			.cpu = 0, .u.virq = virq };

}



static struct irq_info mk_pirq_info(unsigned short evtchn,

static struct irq_info mk_pirq_info(unsigned short evtchn, unsigned short pirq,

				    unsigned short gsi, unsigned short vector)

{

	return (struct irq_info) { .type = IRQT_PIRQ, .evtchn = evtchn,

			.cpu = 0, .u.pirq = { .gsi = gsi, .vector = vector } };

			.cpu = 0,

			.u.pirq = { .pirq = pirq, .gsi = gsi, .vector = vector } };

}



/*
@@ -193,6 +196,16 @@ static unsigned virq_from_irq(unsigned irq) 
	return info->u.virq;

}



static unsigned pirq_from_irq(unsigned irq)

{

	struct irq_info *info = info_for_irq(irq);



	BUG_ON(info == NULL);

	BUG_ON(info->type != IRQT_PIRQ);



	return info->u.pirq.pirq;

}



static unsigned gsi_from_irq(unsigned irq)

{

	struct irq_info *info = info_for_irq(irq);
@@ -365,6 +378,16 @@ static int get_nr_hw_irqs(void) 
	return ret;

}



static int find_unbound_pirq(void)

{

	int i;

	for (i = 0; i < nr_irqs; i++) {

		if (pirq_to_irq[i] < 0)

			return i;

	}

	return -1;

}



static int find_unbound_irq(void)

{

	struct irq_data *data;
@@ -410,7 +433,7 @@ static bool identity_mapped_irq(unsigned irq) 


static void pirq_unmask_notify(int irq)

{

	struct physdev_eoi eoi = { .irq = irq };

	struct physdev_eoi eoi = { .irq = pirq_from_irq(irq) };



	if (unlikely(pirq_needs_eoi(irq))) {

		int rc = HYPERVISOR_physdev_op(PHYSDEVOP_eoi, &eoi);
@@ -425,7 +448,7 @@ static void pirq_query_unmask(int irq) 


	BUG_ON(info->type != IRQT_PIRQ);



	irq_status.irq = irq;

	irq_status.irq = pirq_from_irq(irq);

	if (HYPERVISOR_physdev_op(PHYSDEVOP_irq_status_query, &irq_status))

		irq_status.flags = 0;
@@ -453,7 +476,7 @@ static unsigned int startup_pirq(unsigned int irq) 
	if (VALID_EVTCHN(evtchn))

		goto out;



	bind_pirq.pirq = irq;

	bind_pirq.pirq = pirq_from_irq(irq);

	/* NB. We are happy to share unless we are probing. */

	bind_pirq.flags = info->u.pirq.flags & PIRQ_SHAREABLE ?

					BIND_PIRQ__WILL_SHARE : 0;
@@ -556,28 +579,32 @@ static int find_irq_by_gsi(unsigned gsi) 
	return -1;

}



/* xen_allocate_irq might allocate irqs from the top down, as a

int xen_allocate_pirq(unsigned gsi, int shareable, char *name)

{

	return xen_map_pirq_gsi(gsi, gsi, shareable, name);

}



/* xen_map_pirq_gsi might allocate irqs from the top down, as a

 * consequence don't assume that the irq number returned has a low value

 * or can be used as a pirq number unless you know otherwise.

 *

 * One notable exception is when xen_allocate_irq is called passing an

 * One notable exception is when xen_map_pirq_gsi is called passing an

 * hardware gsi as argument, in that case the irq number returned

 * matches the gsi number passed as first argument.



 * Note: We don't assign an

 * event channel until the irq actually started up.  Return an

 * existing irq if we've already got one for the gsi.

 * matches the gsi number passed as second argument.

 *

 * Note: We don't assign an event channel until the irq actually started

 * up.  Return an existing irq if we've already got one for the gsi.

 */

int xen_allocate_pirq(unsigned gsi, int shareable, char *name)

int xen_map_pirq_gsi(unsigned pirq, unsigned gsi, int shareable, char *name)

{

	int irq;

	int irq = 0;

	struct physdev_irq irq_op;



	spin_lock(&irq_mapping_update_lock);



	irq = find_irq_by_gsi(gsi);

	if (irq != -1) {

		printk(KERN_INFO "xen_allocate_pirq: returning irq %d for gsi %u\n",

		printk(KERN_INFO "xen_map_pirq_gsi: returning irq %d for gsi %u\n",

		       irq, gsi);

		goto out;	/* XXX need refcount? */

	}
@@ -606,8 +633,9 @@ int xen_allocate_pirq(unsigned gsi, int shareable, char *name) 
		goto out;

	}



	irq_info[irq] = mk_pirq_info(0, gsi, irq_op.vector);

	irq_info[irq] = mk_pirq_info(0, pirq, gsi, irq_op.vector);

	irq_info[irq].u.pirq.flags |= shareable ? PIRQ_SHAREABLE : 0;

	pirq_to_irq[pirq] = irq;



out:

	spin_unlock(&irq_mapping_update_lock);
@@ -1327,6 +1355,10 @@ void __init xen_init_IRQ(void) 
				    GFP_KERNEL);

	irq_info = kcalloc(nr_irqs, sizeof(*irq_info), GFP_KERNEL);



	pirq_to_irq = kcalloc(nr_irqs, sizeof(*pirq_to_irq), GFP_KERNEL);

	for (i = 0; i < nr_irqs; i++)

		pirq_to_irq[i] = -1;



	evtchn_to_irq = kcalloc(NR_EVENT_CHANNELS, sizeof(*evtchn_to_irq),

				    GFP_KERNEL);

	for (i = 0; i < NR_EVENT_CHANNELS; i++)

include/xen/events.h

+1 −0
Original line number Diff line number Diff line
@@ -71,6 +71,7 @@ void xen_hvm_evtchn_do_upcall(void); 
 * GSIs are identity mapped; others are dynamically allocated as

 * usual. */

int xen_allocate_pirq(unsigned gsi, int shareable, char *name);

int xen_map_pirq_gsi(unsigned pirq, unsigned gsi, int shareable, char *name);



/* De-allocates the above mentioned physical interrupt. */

int xen_destroy_irq(int irq);

CRA Git | Maintained and supported by SUSTech CRA and CCSE