From 15ebbb82bac700db3c91e662fb70cb3559e9d930 Mon Sep 17 00:00:00 2001
From: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Date: Mon, 4 Oct 2010 13:43:27 -0400
Subject: [PATCH] xen: fix shared irq device passthrough
In driver/xen/events.c, whether bind_pirq is shareable or not is
determined by desc->action is NULL or not. But in __setup_irq,
startup(irq) is invoked before desc->action is assigned with
new action. So desc->action in startup_irq is always NULL, and
bind_pirq is always not shareable. This results in pt_irq_create_bind
failure when passthrough a device which shares irq to other devices.
This patch doesn't use probing_irq to determine if pirq is shareable
or not, instead set shareable flag in irq_info according to trigger
mode in xen_allocate_pirq. Set level triggered interrupts shareable.
Thus use this flag to set bind_pirq flag accordingly.
[v2: arch/x86/xen/pci.c no more, so file skipped]
Signed-off-by: Weidong Han <weidong.han@intel.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
---
drivers/xen/events.c | 11 ++++++++---
include/xen/events.h | 2 +-
2 files changed, 9 insertions(+), 4 deletions(-)
diff --git a/drivers/xen/events.c b/drivers/xen/events.c
index 4e0f868517be..cd504092299b 100644
--- a/drivers/xen/events.c
+++ b/drivers/xen/events.c
@@ -97,6 +97,7 @@ struct irq_info
} u;
};
#define PIRQ_NEEDS_EOI (1 << 0)
+#define PIRQ_SHAREABLE (1 << 1)
static struct irq_info *irq_info;
@@ -445,6 +446,7 @@ static unsigned int startup_pirq(unsigned int irq)
struct evtchn_bind_pirq bind_pirq;
struct irq_info *info = info_for_irq(irq);
int evtchn = evtchn_from_irq(irq);
+ int rc;
BUG_ON(info->type != IRQT_PIRQ);
@@ -453,8 +455,10 @@ static unsigned int startup_pirq(unsigned int irq)
bind_pirq.pirq = irq;
/* NB. We are happy to share unless we are probing. */
- bind_pirq.flags = probing_irq(irq) ? 0 : BIND_PIRQ__WILL_SHARE;
- if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_pirq, &bind_pirq) != 0) {
+ bind_pirq.flags = info->u.pirq.flags & PIRQ_SHAREABLE ?
+ BIND_PIRQ__WILL_SHARE : 0;
+ rc = HYPERVISOR_event_channel_op(EVTCHNOP_bind_pirq, &bind_pirq);
+ if (rc != 0) {
if (!probing_irq(irq))
printk(KERN_INFO "Failed to obtain physical IRQ %d\n",
irq);
@@ -564,7 +568,7 @@ static int find_irq_by_gsi(unsigned gsi)
* 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, char *name)
+int xen_allocate_pirq(unsigned gsi, int shareable, char *name)
{
int irq;
struct physdev_irq irq_op;
@@ -596,6 +600,7 @@ int xen_allocate_pirq(unsigned gsi, char *name)
}
irq_info[irq] = mk_pirq_info(0, gsi, irq_op.vector);
+ irq_info[irq].u.pirq.flags |= shareable ? PIRQ_SHAREABLE : 0;
out:
spin_unlock(&irq_mapping_update_lock);
diff --git a/include/xen/events.h b/include/xen/events.h
index 2532f8bd2401..d7a4ca7d17b5 100644
--- a/include/xen/events.h
+++ b/include/xen/events.h
@@ -70,7 +70,7 @@ void xen_hvm_evtchn_do_upcall(void);
/* Allocate an irq for a physical interrupt, given a gsi. "Legacy"
* GSIs are identity mapped; others are dynamically allocated as
* usual. */
-int xen_allocate_pirq(unsigned gsi, char *name);
+int xen_allocate_pirq(unsigned gsi, int shareable, char *name);
/* Return vector allocated to pirq */
int xen_vector_from_irq(unsigned pirq);
--
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