[Xen-devel,v4,10/33] xen/arm: Allow virq != irq

Message ID 1426793399-6283-11-git-send-email-julien.grall@linaro.org
State New
Headers show

Commit Message

Julien Grall March 19, 2015, 7:29 p.m.
Currently, Xen is assuming that the virtual IRQ will always be the same
as IRQ.

Modify route_guest_irq to take the virtual IRQ in parameter which allow
Xen to assign a different IRQ number. Also store the vIRQ in the desc
action to easily retrieve the IRQ target when we need to inject the
interrupt.

As DOM0 will get most the devices, the vIRQ is equal to the IRQ in that case.

At the same time modify the behavior of irq_get_domain. The function now
requires that the irq_desc belongs to an IRQ assigned to a guest.

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

---
    Changes in v4:
        - Add Stefano's ack
        - Typoes and rewording the commit message

    Changes in v3
        - Spelling/grammar nits
        - Fix compilation on ARM64. Forgot to update route_irq_to_guest
          call for xgene platform.
        - Add a word about irq_get_domain behavior change
        - More s/irq/virq/ because of the rebasing on the latest staging

    Changes in v2:
        - Patch added
---
 xen/arch/arm/domain_build.c          |  2 +-
 xen/arch/arm/gic.c                   |  5 ++--
 xen/arch/arm/irq.c                   | 47 ++++++++++++++++++++++++++----------
 xen/arch/arm/platforms/xgene-storm.c |  2 +-
 xen/arch/arm/vgic.c                  | 20 +++++++--------
 xen/include/asm-arm/gic.h            |  3 ++-
 xen/include/asm-arm/irq.h            |  4 +--
 xen/include/asm-arm/vgic.h           |  4 +--
 8 files changed, 55 insertions(+), 32 deletions(-)

Patch

diff --git a/xen/arch/arm/domain_build.c b/xen/arch/arm/domain_build.c
index 2eb31ad..24a0242 100644
--- a/xen/arch/arm/domain_build.c
+++ b/xen/arch/arm/domain_build.c
@@ -1020,7 +1020,7 @@  static int handle_device(struct domain *d, struct dt_device_node *dev)
              * twice the IRQ. This can happen if the IRQ is shared
              */
             vgic_reserve_virq(d, irq);
-            res = route_irq_to_guest(d, irq, dt_node_name(dev));
+            res = route_irq_to_guest(d, irq, irq, dt_node_name(dev));
             if ( res )
             {
                 printk(XENLOG_ERR "Unable to route IRQ %u to domain %u\n",
diff --git a/xen/arch/arm/gic.c b/xen/arch/arm/gic.c
index ba7950b..fe8f69b 100644
--- a/xen/arch/arm/gic.c
+++ b/xen/arch/arm/gic.c
@@ -126,7 +126,8 @@  void gic_route_irq_to_xen(struct irq_desc *desc, const cpumask_t *cpu_mask,
 /* Program the GIC to route an interrupt to a guest
  *   - desc.lock must be held
  */
-void gic_route_irq_to_guest(struct domain *d, struct irq_desc *desc,
+void gic_route_irq_to_guest(struct domain *d, unsigned int virq,
+                            struct irq_desc *desc,
                             const cpumask_t *cpu_mask, unsigned int priority)
 {
     struct pending_irq *p;
@@ -139,7 +140,7 @@  void gic_route_irq_to_guest(struct domain *d, struct irq_desc *desc,
 
     /* 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 = irq_to_pending(d->vcpu[0], virq);
     p->desc = desc;
 }
 
diff --git a/xen/arch/arm/irq.c b/xen/arch/arm/irq.c
index cb9c99b..beb746a 100644
--- a/xen/arch/arm/irq.c
+++ b/xen/arch/arm/irq.c
@@ -31,6 +31,13 @@ 
 static unsigned int local_irqs_type[NR_LOCAL_IRQS];
 static DEFINE_SPINLOCK(local_irqs_type_lock);
 
+/* Describe an IRQ assigned to a guest */
+struct irq_guest
+{
+    struct domain *d;
+    unsigned int virq;
+};
+
 static void ack_none(struct irq_desc *irq)
 {
     printk("unexpected IRQ trap at irq %02x\n", irq->irq);
@@ -122,18 +129,20 @@  void __cpuinit init_secondary_IRQ(void)
     BUG_ON(init_local_irq_data() < 0);
 }
 
-static inline struct domain *irq_get_domain(struct irq_desc *desc)
+static inline struct irq_guest *irq_get_guest_info(struct irq_desc *desc)
 {
     ASSERT(spin_is_locked(&desc->lock));
-
-    if ( !test_bit(_IRQ_GUEST, &desc->status) )
-        return dom_xen;
-
+    ASSERT(test_bit(_IRQ_GUEST, &desc->status));
     ASSERT(desc->action != NULL);
 
     return desc->action->dev_id;
 }
 
+static inline struct domain *irq_get_domain(struct irq_desc *desc)
+{
+    return irq_get_guest_info(desc)->d;
+}
+
 void irq_set_affinity(struct irq_desc *desc, const cpumask_t *cpu_mask)
 {
     if ( desc != NULL )
@@ -204,7 +213,7 @@  void do_IRQ(struct cpu_user_regs *regs, unsigned int irq, int is_fiq)
 
     if ( test_bit(_IRQ_GUEST, &desc->status) )
     {
-        struct domain *d = irq_get_domain(desc);
+        struct irq_guest *info = irq_get_guest_info(desc);
 
         perfc_incr(guest_irqs);
         desc->handler->end(desc);
@@ -214,7 +223,7 @@  void do_IRQ(struct cpu_user_regs *regs, unsigned int irq, int is_fiq)
 
         /* the irq cannot be a PPI, we only support delivery of SPIs to
          * guests */
-        vgic_vcpu_inject_spi(d, irq);
+        vgic_vcpu_inject_spi(info->d, info->virq);
         goto out_no_end;
     }
 
@@ -378,19 +387,30 @@  err:
     return rc;
 }
 
-int route_irq_to_guest(struct domain *d, unsigned int irq,
-                       const char * devname)
+int route_irq_to_guest(struct domain *d, unsigned int virq,
+                       unsigned int irq, const char * devname)
 {
     struct irqaction *action;
-    struct irq_desc *desc = irq_to_desc(irq);
+    struct irq_guest *info;
+    struct irq_desc *desc;
     unsigned long flags;
     int retval = 0;
 
     action = xmalloc(struct irqaction);
-    if (!action)
+    if ( !action )
+        return -ENOMEM;
+
+    info = xmalloc(struct irq_guest);
+    if ( !info )
+    {
+        xfree(action);
         return -ENOMEM;
+    }
+
+    info->d = d;
+    info->virq = virq;
 
-    action->dev_id = d;
+    action->dev_id = info;
     action->name = devname;
     action->free_on_release = 1;
 
@@ -421,7 +441,7 @@  int route_irq_to_guest(struct domain *d, unsigned int irq,
     if ( retval )
         goto out;
 
-    gic_route_irq_to_guest(d, desc, cpumask_of(smp_processor_id()),
+    gic_route_irq_to_guest(d, virq, desc, cpumask_of(smp_processor_id()),
                            GIC_PRI_IRQ);
     spin_unlock_irqrestore(&desc->lock, flags);
     return 0;
@@ -429,6 +449,7 @@  int route_irq_to_guest(struct domain *d, unsigned int irq,
 out:
     spin_unlock_irqrestore(&desc->lock, flags);
     xfree(action);
+    xfree(info);
 
     return retval;
 }
diff --git a/xen/arch/arm/platforms/xgene-storm.c b/xen/arch/arm/platforms/xgene-storm.c
index eee650e..1812e5b 100644
--- a/xen/arch/arm/platforms/xgene-storm.c
+++ b/xen/arch/arm/platforms/xgene-storm.c
@@ -75,7 +75,7 @@  static int map_one_spi(struct domain *d, const char *what,
         printk("Failed to reserve vIRQ %u on dom%d\n",
                irq, d->domain_id);
 
-    ret = route_irq_to_guest(d, irq, what);
+    ret = route_irq_to_guest(d, irq, irq, what);
     if ( ret )
         printk("Failed to route %s to dom%d\n", what, d->domain_id);
 
diff --git a/xen/arch/arm/vgic.c b/xen/arch/arm/vgic.c
index 0b4fa57..c07822f 100644
--- a/xen/arch/arm/vgic.c
+++ b/xen/arch/arm/vgic.c
@@ -382,16 +382,16 @@  void vgic_clear_pending_irqs(struct vcpu *v)
     spin_unlock_irqrestore(&v->arch.vgic.lock, flags);
 }
 
-void vgic_vcpu_inject_irq(struct vcpu *v, unsigned int irq)
+void vgic_vcpu_inject_irq(struct vcpu *v, unsigned int virq)
 {
     uint8_t priority;
-    struct vgic_irq_rank *rank = vgic_rank_irq(v, irq);
-    struct pending_irq *iter, *n = irq_to_pending(v, irq);
+    struct vgic_irq_rank *rank = vgic_rank_irq(v, virq);
+    struct pending_irq *iter, *n = irq_to_pending(v, virq);
     unsigned long flags;
     bool_t running;
 
     vgic_lock_rank(v, rank, flags);
-    priority = v->domain->arch.vgic.handler->get_irq_priority(v, irq);
+    priority = v->domain->arch.vgic.handler->get_irq_priority(v, virq);
     vgic_unlock_rank(v, rank, flags);
 
     spin_lock_irqsave(&v->arch.vgic.lock, flags);
@@ -407,7 +407,7 @@  void vgic_vcpu_inject_irq(struct vcpu *v, unsigned int irq)
 
     if ( !list_empty(&n->inflight) )
     {
-        gic_raise_inflight_irq(v, irq);
+        gic_raise_inflight_irq(v, virq);
         goto out;
     }
 
@@ -415,7 +415,7 @@  void vgic_vcpu_inject_irq(struct vcpu *v, unsigned int irq)
 
     /* the irq is enabled */
     if ( test_bit(GIC_IRQ_GUEST_ENABLED, &n->status) )
-        gic_raise_guest_irq(v, irq, priority);
+        gic_raise_guest_irq(v, virq, priority);
 
     list_for_each_entry ( iter, &v->arch.vgic.inflight_irqs, inflight )
     {
@@ -438,15 +438,15 @@  out:
     }
 }
 
-void vgic_vcpu_inject_spi(struct domain *d, unsigned int irq)
+void vgic_vcpu_inject_spi(struct domain *d, unsigned int virq)
 {
     struct vcpu *v;
 
     /* the IRQ needs to be an SPI */
-    ASSERT(irq >= 32 && irq <= gic_number_lines());
+    ASSERT(virq >= 32 && virq <= vgic_num_irqs(d));
 
-    v = vgic_get_target_vcpu(d->vcpu[0], irq);
-    vgic_vcpu_inject_irq(v, irq);
+    v = vgic_get_target_vcpu(d->vcpu[0], virq);
+    vgic_vcpu_inject_irq(v, virq);
 }
 
 void arch_evtchn_inject(struct vcpu *v)
diff --git a/xen/include/asm-arm/gic.h b/xen/include/asm-arm/gic.h
index b16f98e..bb2a922 100644
--- a/xen/include/asm-arm/gic.h
+++ b/xen/include/asm-arm/gic.h
@@ -216,7 +216,8 @@  extern enum gic_version gic_hw_version(void);
 /* Program the GIC to route an interrupt */
 extern void gic_route_irq_to_xen(struct irq_desc *desc, const cpumask_t *cpu_mask,
                                  unsigned int priority);
-extern void gic_route_irq_to_guest(struct domain *, struct irq_desc *desc,
+extern void gic_route_irq_to_guest(struct domain *, unsigned int virq,
+                                   struct irq_desc *desc,
                                    const cpumask_t *cpu_mask,
                                    unsigned int priority);
 
diff --git a/xen/include/asm-arm/irq.h b/xen/include/asm-arm/irq.h
index 435dfcd..f00eb11 100644
--- a/xen/include/asm-arm/irq.h
+++ b/xen/include/asm-arm/irq.h
@@ -40,8 +40,8 @@  void do_IRQ(struct cpu_user_regs *regs, unsigned int irq, int is_fiq);
 void init_IRQ(void);
 void init_secondary_IRQ(void);
 
-int route_irq_to_guest(struct domain *d, unsigned int irq,
-                       const char *devname);
+int route_irq_to_guest(struct domain *d, unsigned int virq,
+                       unsigned int irq, const char *devname);
 void arch_move_irqs(struct vcpu *v);
 
 /* Set IRQ type for an SPI */
diff --git a/xen/include/asm-arm/vgic.h b/xen/include/asm-arm/vgic.h
index 0d0d114..aba0d80 100644
--- a/xen/include/asm-arm/vgic.h
+++ b/xen/include/asm-arm/vgic.h
@@ -181,8 +181,8 @@  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 struct vcpu *vgic_get_target_vcpu(struct vcpu *v, unsigned int irq);
-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_vcpu_inject_irq(struct vcpu *v, unsigned int virq);
+extern void vgic_vcpu_inject_spi(struct domain *d, unsigned int virq);
 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);