xen/arm: implement do_hvm_op for ARM

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Tim Deegan <tim@xen.org>
Committed-by: Ian Campbell <ian.campbell@citrix.com>

xen/arch/arm/Makefile

@@ -26,6 +26,7 @@ obj-y += traps.o
 obj-y += vgic.o
 obj-y += vtimer.o
 obj-y += vpl011.o
+obj-y += hvm.o
 
 #obj-bin-y += ....o
 

xen/arch/arm/hvm.c

@@ -0,0 +1,60 @@
+#include <xen/config.h>
+#include <xen/init.h>
+#include <xen/lib.h>
+#include <xen/errno.h>
+#include <xen/guest_access.h>
+#include <xen/sched.h>
+
+#include <public/xen.h>
+#include <public/hvm/params.h>
+#include <public/hvm/hvm_op.h>
+
+#include <asm/hypercall.h>
+
+long do_hvm_op(unsigned long op, XEN_GUEST_HANDLE(void) arg)
+
+{
+    long rc = 0;
+
+    switch ( op )
+    {
+    case HVMOP_set_param:
+    case HVMOP_get_param:
+    {
+        struct xen_hvm_param a;
+        struct domain *d;
+
+        if ( copy_from_guest(&a, arg, 1) )
+            return -EFAULT;
+
+        if ( a.index >= HVM_NR_PARAMS )
+            return -EINVAL;
+
+        rc = rcu_lock_target_domain_by_id(a.domid, &d);
+        if ( rc != 0 )
+            return rc;
+
+        if ( op == HVMOP_set_param )
+        {
+            d->arch.hvm_domain.params[a.index] = a.value;
+        }
+        else
+        {
+            a.value = d->arch.hvm_domain.params[a.index];
+            rc = copy_to_guest(arg, &a, 1) ? -EFAULT : 0;
+        }
+
+        rcu_unlock_domain(d);
+        break;
+    }
+
+    default:
+    {
+        printk("%s: Bad HVM op %ld.\n", __func__, op);
+        rc = -ENOSYS;
+        break;
+    }
+    }
+
+    return rc;
+}

xen/arch/arm/traps.c

@@ -430,6 +430,7 @@ static arm_hypercall_t *arm_hypercall_table[] = {
     HYPERCALL(memory_op),
     HYPERCALL(physdev_op),
     HYPERCALL(sysctl),
+    HYPERCALL(hvm_op),
 };
 
 static void do_debug_trap(struct cpu_user_regs *regs, unsigned int code)

xen/include/asm-arm/domain.h

@@ -5,6 +5,7 @@
 #include <xen/cache.h>
 #include <asm/page.h>
 #include <asm/p2m.h>
+#include <public/hvm/params.h>
 
 /* Represents state corresponding to a block of 32 interrupts */
 struct vgic_irq_rank {
@@ -28,9 +29,15 @@ struct pending_irq
     struct list_head lr_queue;
 };
 
+struct hvm_domain
+{
+    uint64_t              params[HVM_NR_PARAMS];
+}  __cacheline_aligned;
+
 struct arch_domain
 {
     struct p2m_domain p2m;
+    struct hvm_domain hvm_domain;
 
     struct {
         /*