[PATCH v8 04/10] xen/arm: support irq delivery to vcpu > 0

[Stefano Stabellini <stefano.stabellini@eu.citrix.com>]

Use vgic_get_target_vcpu to retrieve the target vcpu from do_IRQ.
Remove in-code comments about missing implementation of SGI delivery to
vcpus other than 0.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Julien Grall <julien.grall@linaro.org>
Acked-by: Ian Campbell <ian.campbell@citrix.com>

---

Changes in v7:
- improve in-code comment;
- use gic_number_lines in assert.

Changes in v6:
- add in-code comments;
- assert that the guest irq is an SPI.

Changes in v4:
- the mask in gic_route_irq_to_guest is a physical cpu mask, treat it as
such;
- export vgic_get_target_vcpu in a previous patch.
---
 xen/arch/arm/gic.c         |    3 ++-
 xen/arch/arm/irq.c         |    5 +++--
 xen/arch/arm/vgic.c        |   11 +++++++++++
 xen/include/asm-arm/vgic.h |    1 +
 4 files changed, 17 insertions(+), 3 deletions(-)

diff --git a/xen/arch/arm/gic.c b/xen/arch/arm/gic.c
index a0252f9..884661c 100644
--- a/xen/arch/arm/gic.c
+++ b/xen/arch/arm/gic.c
@@ -137,7 +137,8 @@ void gic_route_irq_to_guest(struct domain *d, struct irq_desc *desc,
 
     gic_set_irq_properties(desc, cpumask_of(smp_processor_id()), GIC_PRI_IRQ);
 
-    /* TODO: do not assume delivery to vcpu0 */
+    /* Use vcpu0 to retrieve the pending_irq struct. Given that we only
+     * route SPIs to guests, it doesn't make any difference. */
     p = irq_to_pending(d->vcpu[0], desc->irq);
     p->desc = desc;
 }
diff --git a/xen/arch/arm/irq.c b/xen/arch/arm/irq.c
index 3a8acbf..49ca467 100644
--- a/xen/arch/arm/irq.c
+++ b/xen/arch/arm/irq.c
@@ -198,8 +198,9 @@ void do_IRQ(struct cpu_user_regs *regs, unsigned int irq, int is_fiq)
         desc->status |= IRQ_INPROGRESS;
         desc->arch.eoi_cpu = smp_processor_id();
 
-        /* XXX: inject irq into all guest vcpus */
-        vgic_vcpu_inject_irq(d->vcpu[0], irq);
+        /* the irq cannot be a PPI, we only support delivery of SPIs to
+         * guests */
+        vgic_vcpu_inject_spi(d, irq);
         goto out_no_end;
     }
 
diff --git a/xen/arch/arm/vgic.c b/xen/arch/arm/vgic.c
index fbe3293..5445a7b 100644
--- a/xen/arch/arm/vgic.c
+++ b/xen/arch/arm/vgic.c
@@ -434,6 +434,17 @@ out:
         smp_send_event_check_mask(cpumask_of(v->processor));
 }
 
+void vgic_vcpu_inject_spi(struct domain *d, unsigned int irq)
+{
+    struct vcpu *v;
+
+    /* the IRQ needs to be an SPI */
+    ASSERT(irq >= 32 && irq <= gic_number_lines());
+
+    v = vgic_get_target_vcpu(d->vcpu[0], irq);
+    vgic_vcpu_inject_irq(v, irq);
+}
+
 /*
  * Local variables:
  * mode: C
diff --git a/xen/include/asm-arm/vgic.h b/xen/include/asm-arm/vgic.h
index c66578b..e961780 100644
--- a/xen/include/asm-arm/vgic.h
+++ b/xen/include/asm-arm/vgic.h
@@ -159,6 +159,7 @@ extern int domain_vgic_init(struct domain *d);
 extern void domain_vgic_free(struct domain *d);
 extern int vcpu_vgic_init(struct vcpu *v);
 extern void vgic_vcpu_inject_irq(struct vcpu *v, unsigned int irq);
+extern void vgic_vcpu_inject_spi(struct domain *d, unsigned int irq);
 extern void vgic_clear_pending_irqs(struct vcpu *v);
 extern struct pending_irq *irq_to_pending(struct vcpu *v, unsigned int irq);
 extern struct vgic_irq_rank *vgic_rank_offset(struct vcpu *v, int b, int n, int s);
-- 
1.7.10.4