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Diffstat (limited to 'arch/x86/xen/enlighten_hvm.c')
-rw-r--r--arch/x86/xen/enlighten_hvm.c59
1 files changed, 37 insertions, 22 deletions
diff --git a/arch/x86/xen/enlighten_hvm.c b/arch/x86/xen/enlighten_hvm.c
index 87d791356ea9..de503c225ae1 100644
--- a/arch/x86/xen/enlighten_hvm.c
+++ b/arch/x86/xen/enlighten_hvm.c
@@ -12,6 +12,7 @@
#include <asm/setup.h>
#include <asm/hypervisor.h>
#include <asm/e820/api.h>
+#include <asm/early_ioremap.h>
#include <asm/xen/cpuid.h>
#include <asm/xen/hypervisor.h>
@@ -21,38 +22,50 @@
#include "mmu.h"
#include "smp.h"
-void __ref xen_hvm_init_shared_info(void)
+static unsigned long shared_info_pfn;
+
+void xen_hvm_init_shared_info(void)
{
struct xen_add_to_physmap xatp;
- u64 pa;
-
- if (HYPERVISOR_shared_info == &xen_dummy_shared_info) {
- /*
- * Search for a free page starting at 4kB physical address.
- * Low memory is preferred to avoid an EPT large page split up
- * by the mapping.
- * Starting below X86_RESERVE_LOW (usually 64kB) is fine as
- * the BIOS used for HVM guests is well behaved and won't
- * clobber memory other than the first 4kB.
- */
- for (pa = PAGE_SIZE;
- !e820__mapped_all(pa, pa + PAGE_SIZE, E820_TYPE_RAM) ||
- memblock_is_reserved(pa);
- pa += PAGE_SIZE)
- ;
-
- memblock_reserve(pa, PAGE_SIZE);
- HYPERVISOR_shared_info = __va(pa);
- }
xatp.domid = DOMID_SELF;
xatp.idx = 0;
xatp.space = XENMAPSPACE_shared_info;
- xatp.gpfn = virt_to_pfn(HYPERVISOR_shared_info);
+ xatp.gpfn = shared_info_pfn;
if (HYPERVISOR_memory_op(XENMEM_add_to_physmap, &xatp))
BUG();
}
+static void __init reserve_shared_info(void)
+{
+ u64 pa;
+
+ /*
+ * Search for a free page starting at 4kB physical address.
+ * Low memory is preferred to avoid an EPT large page split up
+ * by the mapping.
+ * Starting below X86_RESERVE_LOW (usually 64kB) is fine as
+ * the BIOS used for HVM guests is well behaved and won't
+ * clobber memory other than the first 4kB.
+ */
+ for (pa = PAGE_SIZE;
+ !e820__mapped_all(pa, pa + PAGE_SIZE, E820_TYPE_RAM) ||
+ memblock_is_reserved(pa);
+ pa += PAGE_SIZE)
+ ;
+
+ shared_info_pfn = PHYS_PFN(pa);
+
+ memblock_reserve(pa, PAGE_SIZE);
+ HYPERVISOR_shared_info = early_memremap(pa, PAGE_SIZE);
+}
+
+static void __init xen_hvm_init_mem_mapping(void)
+{
+ early_memunmap(HYPERVISOR_shared_info, PAGE_SIZE);
+ HYPERVISOR_shared_info = __va(PFN_PHYS(shared_info_pfn));
+}
+
static void __init init_hvm_pv_info(void)
{
int major, minor;
@@ -153,6 +166,7 @@ static void __init xen_hvm_guest_init(void)
init_hvm_pv_info();
+ reserve_shared_info();
xen_hvm_init_shared_info();
/*
@@ -218,5 +232,6 @@ const struct hypervisor_x86 x86_hyper_xen_hvm = {
.init_platform = xen_hvm_guest_init,
.pin_vcpu = xen_pin_vcpu,
.x2apic_available = xen_x2apic_para_available,
+ .init_mem_mapping = xen_hvm_init_mem_mapping,
};
EXPORT_SYMBOL(x86_hyper_xen_hvm);