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, 10 insertions, 7 deletions

diff --git a/xen/arch/x86/hvm/i8254.c b/xen/arch/x86/hvm/i8254.c
index 702a843640..c0d6bc29b6 100644
--- a/xen/arch/x86/hvm/i8254.c
+++ b/xen/arch/x86/hvm/i8254.c
@@ -38,10 +38,9 @@
 #include <asm/hvm/vpt.h>
 #include <asm/current.h>
 
-#define domain_vpit(x) (&(x)->arch.hvm_domain.pl_time.vpit)
+#define domain_vpit(x) (&(x)->arch.vpit)
 #define vcpu_vpit(x)   (domain_vpit((x)->domain))
-#define vpit_domain(x) (container_of((x), struct domain, \
-                                     arch.hvm_domain.pl_time.vpit))
+#define vpit_domain(x) (container_of((x), struct domain, arch.vpit))
 #define vpit_vcpu(x)   (pt_global_vcpu_target(vpit_domain(x)))
 
 #define RW_STATE_LSB 1
@@ -450,14 +449,18 @@ void pit_reset(struct domain *d)
 
 void pit_init(struct vcpu *v, unsigned long cpu_khz)
 {
-    PITState *pit = vcpu_vpit(v);
+    struct domain *d = v->domain;
+    PITState *pit = domain_vpit(d);
 
     spin_lock_init(&pit->lock);
 
-    register_portio_handler(v->domain, PIT_BASE, 4, handle_pit_io);
-    register_portio_handler(v->domain, 0x61, 1, handle_speaker_io);
+    if ( is_hvm_domain(d) )
+    {
+        register_portio_handler(d, PIT_BASE, 4, handle_pit_io);
+        register_portio_handler(d, 0x61, 1, handle_speaker_io);
+    }
 
-    pit_reset(v->domain);
+    pit_reset(d);
 }
 
 void pit_deinit(struct domain *d)