[MINI-OS PATCH 2/6] setup: drop parameter from map_shared_info()

[Juergen Gross <jgross@xxxxxxxx>]

The parameter of map_shared_info() is evaluated in PV mode only, and it
is always the pointer to the initial struct start_info from boot time.

By setting start_info_ptr a little bit earlier the PV variant of
map_shared_info() can just use start_info_ptr instead of a parameter.

Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
---
 arch/arm/setup.c     |  2 +-
 arch/x86/setup.c     | 12 ++++++------
 hypervisor.c         |  2 +-
 include/hypervisor.h |  2 +-
 4 files changed, 9 insertions(+), 9 deletions(-)

diff --git a/arch/arm/setup.c b/arch/arm/setup.c
index 3d112fae..1bcfa689 100644
--- a/arch/arm/setup.c
+++ b/arch/arm/setup.c
@@ -38,7 +38,7 @@ void arch_init(void *dtb_pointer, uint32_t physical_offset)
     device_tree = dtb_pointer;
 
     /* Map shared_info page */
-    HYPERVISOR_shared_info = map_shared_info(NULL);
+    HYPERVISOR_shared_info = map_shared_info();
 
     get_console(NULL);
     get_xenbus(NULL);
diff --git a/arch/x86/setup.c b/arch/x86/setup.c
index e30eb065..1bdf9509 100644
--- a/arch/x86/setup.c
+++ b/arch/x86/setup.c
@@ -79,11 +79,10 @@ static inline void sse_init(void) {
 #ifdef CONFIG_PARAVIRT
 #define hpc_init()
 
-shared_info_t *map_shared_info(void *p)
+shared_info_t *map_shared_info(void)
 {
     int rc;
-    start_info_t *si = p;
-    unsigned long pa = si->shared_info;
+    unsigned long pa = start_info_ptr->shared_info;
 
     if ( (rc = HYPERVISOR_update_va_mapping((unsigned long)shared_info,
                                             __pte(pa | 7), UVMF_INVLPG)) )
@@ -185,6 +184,8 @@ arch_init(void *par)
 {
        static char hello[] = "Bootstrapping...\n";
 
+       start_info_ptr = par;
+
        hpc_init();
        (void)HYPERVISOR_console_io(CONSOLEIO_write, strlen(hello), hello);
 
@@ -206,7 +207,7 @@ arch_init(void *par)
        get_cmdline(par);
 
        /* Grab the shared_info pointer and put it in a safe place. */
-       HYPERVISOR_shared_info = map_shared_info(par);
+       HYPERVISOR_shared_info = map_shared_info();
 
        /* print out some useful information  */
        print_start_of_day(par);
@@ -214,7 +215,6 @@ arch_init(void *par)
 #ifdef CONFIG_PARAVIRT
        memcpy(&start_info, par, sizeof(start_info));
 #endif
-       start_info_ptr = (start_info_t *)par;
 
        start_kernel();
 }
@@ -253,7 +253,7 @@ void arch_post_suspend(int canceled)
     }
 #endif
 
-    HYPERVISOR_shared_info = map_shared_info((void*) start_info_ptr);
+    HYPERVISOR_shared_info = map_shared_info();
 #ifndef CONFIG_PARAVIRT
     xen_callback_vector();
 #endif
diff --git a/hypervisor.c b/hypervisor.c
index ba535556..6476d658 100644
--- a/hypervisor.c
+++ b/hypervisor.c
@@ -65,7 +65,7 @@ int hvm_set_parameter(int idx, uint64_t value)
     return HYPERVISOR_hvm_op(HVMOP_set_param, &xhv);
 }
 
-shared_info_t *map_shared_info(void *p)
+shared_info_t *map_shared_info(void)
 {
     struct xen_add_to_physmap xatp;
 
diff --git a/include/hypervisor.h b/include/hypervisor.h
index b852a42a..aef142d1 100644
--- a/include/hypervisor.h
+++ b/include/hypervisor.h
@@ -42,7 +42,7 @@ extern union start_info_union start_info_union;
 int hvm_get_parameter(int idx, uint64_t *value);
 int hvm_set_parameter(int idx, uint64_t value);
 #endif
-shared_info_t *map_shared_info(void *p);
+shared_info_t *map_shared_info(void);
 void unmap_shared_info(void);
 void force_evtchn_callback(void);
 void do_hypervisor_callback(struct pt_regs *regs);
-- 
2.43.0