[PATCH] x86/guest: finish conversion to altcall

[Jan Beulich <jbeulich@xxxxxxxx>]

While .setup() and .e820_fixup() don't need fiddling with for being run
only very early, both .ap_setup() and .resume() want converting too:
This way both pre-filled struct hypervisor_ops instances can become
__initconst_cf_clobber, thus allowing to eliminate up to 5 more ENDBR
(configuration dependent) during the 2nd phase of alternatives patching.

While fiddling with section annotations here, also move "ops" itself to
.data.ro_after_init.

Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>

--- a/xen/arch/x86/guest/hyperv/hyperv.c
+++ b/xen/arch/x86/guest/hyperv/hyperv.c
@@ -207,7 +207,7 @@ static int cf_check flush_tlb(
     return hyperv_flush_tlb(mask, va, flags);
 }
 
-static const struct hypervisor_ops __initconstrel ops = {
+static const struct hypervisor_ops __initconst_cf_clobber ops = {
     .name = "Hyper-V",
     .setup = setup,
     .ap_setup = ap_setup,
--- a/xen/arch/x86/guest/hypervisor.c
+++ b/xen/arch/x86/guest/hypervisor.c
@@ -13,7 +13,7 @@
 #include <asm/cache.h>
 #include <asm/guest.h>
 
-static struct hypervisor_ops __read_mostly ops;
+static struct hypervisor_ops __ro_after_init ops;
 
 const char *__init hypervisor_probe(void)
 {
@@ -49,7 +49,7 @@ void __init hypervisor_setup(void)
 int hypervisor_ap_setup(void)
 {
     if ( ops.ap_setup )
-        return ops.ap_setup();
+        return alternative_call(ops.ap_setup);
 
     return 0;
 }
@@ -57,7 +57,7 @@ int hypervisor_ap_setup(void)
 void hypervisor_resume(void)
 {
     if ( ops.resume )
-        ops.resume();
+        alternative_vcall(ops.resume);
 }
 
 void __init hypervisor_e820_fixup(void)
--- a/xen/arch/x86/guest/xen/xen.c
+++ b/xen/arch/x86/guest/xen/xen.c
@@ -318,7 +318,7 @@ static int cf_check flush_tlb(
     return xen_hypercall_hvm_op(HVMOP_flush_tlbs, NULL);
 }
 
-static const struct hypervisor_ops __initconstrel ops = {
+static const struct hypervisor_ops __initconst_cf_clobber ops = {
     .name = "Xen",
     .setup = setup,
     .ap_setup = ap_setup,