x86: split struct domain

This is accomplished by converting a couple of embedded arrays (in one
case a structure containing an array) into separately allocated
pointers, and (just as for struct arch_vcpu in a prior patch)
overlaying some PV-only fields with HVM-only ones.

One particularly noteworthy change in the opposite direction is that
of PITState - this field so far lived in the HVM-only portion, but is
being used by PV guests too, and hence needed to be moved out of
struct hvm_domain.

The change to XENMEM_set_memory_map (and hence libxl__build_pre() and
the movement of the E820 related pieces to struct pv_domain) are
subject to a positive response to a query sent to xen-devel regarding
the need for this to happen for HVM guests (see
http://lists.xensource.com/archives/html/xen-devel/2011-03/msg01848.html).

The protection of arch.hvm_domain.irq.dpci accesses by is_hvm_domain()
is subject to confirmation that the field is used for HVM guests only
(see
http://lists.xensource.com/archives/html/xen-devel/2011-03/msg02004.html).

In the absence of any reply to these queries, and given the early
state of 4.2 development, I think it should be acceptable to take the
risk of having to later undo/redo some of this.

Signed-off-by: Jan Beulich <jbeulich@novell.com>

1 files changed, 8 insertions, 5 deletions

diff --git a/xen/arch/x86/hvm/vpt.c b/xen/arch/x86/hvm/vpt.c
index 7056769ea3..353eda0343 100644
--- a/xen/arch/x86/hvm/vpt.c
+++ b/xen/arch/x86/hvm/vpt.c
@@ -463,17 +463,20 @@ static void pt_adjust_vcpu(struct periodic_time *pt, struct vcpu *v)
 
 void pt_adjust_global_vcpu_target(struct vcpu *v)
 {
+    struct PITState *vpit;
     struct pl_time *pl_time;
     int i;
 
     if ( v == NULL )
         return;
 
-    pl_time = &v->domain->arch.hvm_domain.pl_time;
+    vpit = &v->domain->arch.vpit;
+
+    spin_lock(&vpit->lock);
+    pt_adjust_vcpu(&vpit->pt0, v);
+    spin_unlock(&vpit->lock);
 
-    spin_lock(&pl_time->vpit.lock);
-    pt_adjust_vcpu(&pl_time->vpit.pt0, v);
-    spin_unlock(&pl_time->vpit.lock);
+    pl_time = &v->domain->arch.hvm_domain.pl_time;
 
     spin_lock(&pl_time->vrtc.lock);
     pt_adjust_vcpu(&pl_time->vrtc.pt, v);
@@ -507,7 +510,7 @@ void pt_may_unmask_irq(struct domain *d, struct periodic_time *vlapic_pt)
 
     if ( d )
     {
-        pt_resume(&d->arch.hvm_domain.pl_time.vpit.pt0);
+        pt_resume(&d->arch.vpit.pt0);
         pt_resume(&d->arch.hvm_domain.pl_time.vrtc.pt);
         for ( i = 0; i < HPET_TIMER_NUM; i++ )
             pt_resume(&d->arch.hvm_domain.pl_time.vhpet.pt[i]);