[MINI-OS PATCH 3/6] x86/pv: remove global start_info

[Juergen Gross <jgross@xxxxxxxx>]

Add an extern declaration for start_info_ptr when running in PV mode
and use that instead of the copy held in start_info. This allows to
drop start_info.

Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
---
 arch/x86/setup.c     | 17 +----------------
 console.c            |  2 +-
 include/hypervisor.h | 12 ++----------
 xenbus.c             |  2 +-
 4 files changed, 5 insertions(+), 28 deletions(-)

diff --git a/arch/x86/setup.c b/arch/x86/setup.c
index 1bdf9509..4e2f0749 100644
--- a/arch/x86/setup.c
+++ b/arch/x86/setup.c
@@ -35,17 +35,8 @@
 #include <xen/arch-x86/hvm/start_info.h>
 #include <xen/hvm/params.h>
 
-#ifdef CONFIG_PARAVIRT
-/*
- * This structure contains start-of-day info, such as pagetable base pointer,
- * address of the shared_info structure, and things like that.
- */
-union start_info_union start_info_union;
-EXPORT_SYMBOL(start_info_union);
-#endif
-
 /*
- * This pointer holds a reference to the copy of the start_info struct.
+ * This pointer holds a reference to the start_info struct.
  */
 start_info_t *start_info_ptr;
 
@@ -212,10 +203,6 @@ arch_init(void *par)
        /* print out some useful information  */
        print_start_of_day(par);
 
-#ifdef CONFIG_PARAVIRT
-       memcpy(&start_info, par, sizeof(start_info));
-#endif
-
        start_kernel();
 }
 
@@ -248,8 +235,6 @@ void arch_post_suspend(int canceled)
     if (canceled) {
         start_info_ptr->store_mfn = pfn_to_mfn(start_info_ptr->store_mfn);
         start_info_ptr->console.domU.mfn = 
pfn_to_mfn(start_info_ptr->console.domU.mfn);
-    } else {
-        memcpy(&start_info, start_info_ptr, sizeof(start_info_t));
     }
 #endif
 
diff --git a/console.c b/console.c
index 0107b685..a4c50371 100644
--- a/console.c
+++ b/console.c
@@ -411,7 +411,7 @@ void xencons_ring_resume(struct consfront_dev *dev)
     if ( dev )
     {
 #if CONFIG_PARAVIRT
-        get_console(&start_info);
+        get_console(start_info_ptr);
 #else
         get_console(0);
 #endif
diff --git a/include/hypervisor.h b/include/hypervisor.h
index aef142d1..f40bc8c3 100644
--- a/include/hypervisor.h
+++ b/include/hypervisor.h
@@ -28,16 +28,8 @@
 
 /* hypervisor.c */
 #ifdef CONFIG_PARAVIRT
-/*
- * a placeholder for the start of day information passed up from the hypervisor
- */
-union start_info_union
-{
-    start_info_t start_info;
-    char padding[512];
-};
-extern union start_info_union start_info_union;
-#define start_info (start_info_union.start_info)
+/* A pointer to the start of day information passed up from the hypervisor. */
+extern start_info_t *start_info_ptr;
 #else
 int hvm_get_parameter(int idx, uint64_t *value);
 int hvm_set_parameter(int idx, uint64_t value);
diff --git a/xenbus.c b/xenbus.c
index 686428a4..43fdebd7 100644
--- a/xenbus.c
+++ b/xenbus.c
@@ -469,7 +469,7 @@ void resume_xenbus(int canceled)
     struct xsd_sockmsg *rep;
 
 #ifdef CONFIG_PARAVIRT
-    get_xenbus(&start_info);
+    get_xenbus(start_info_ptr);
 #else
     get_xenbus(0);
 #endif
-- 
2.43.0