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, 3 insertions, 4 deletions

diff --git a/xen/arch/x86/hvm/intercept.c b/xen/arch/x86/hvm/intercept.c
index 54f0f8cc17..4f461cbd4c 100644
--- a/xen/arch/x86/hvm/intercept.c
+++ b/xen/arch/x86/hvm/intercept.c
@@ -195,8 +195,7 @@ static int process_portio_intercept(portio_action_t action, ioreq_t *p)
 int hvm_io_intercept(ioreq_t *p, int type)
 {
     struct vcpu *v = current;
-    struct hvm_io_handler *handler =
-        &v->domain->arch.hvm_domain.io_handler;
+    struct hvm_io_handler *handler = v->domain->arch.hvm_domain.io_handler;
     int i;
     unsigned long addr, size;
 
@@ -230,7 +229,7 @@ void register_io_handler(
     struct domain *d, unsigned long addr, unsigned long size,
     void *action, int type)
 {
-    struct hvm_io_handler *handler = &d->arch.hvm_domain.io_handler;
+    struct hvm_io_handler *handler = d->arch.hvm_domain.io_handler;
     int num = handler->num_slot;
 
     BUG_ON(num >= MAX_IO_HANDLER);
@@ -246,7 +245,7 @@ void relocate_io_handler(
     struct domain *d, unsigned long old_addr, unsigned long new_addr,
     unsigned long size, int type)
 {
-    struct hvm_io_handler *handler = &d->arch.hvm_domain.io_handler;
+    struct hvm_io_handler *handler = d->arch.hvm_domain.io_handler;
     int i;
 
     for ( i = 0; i < handler->num_slot; i++ )