KVM: x86/mmu: Use common logic for computing the 32/64-bit base PA mask

Use common logic for computing PT_BASE_ADDR_MASK for 32-bit, 64-bit, and
EPT paging.  Both PAGE_MASK and the new-common logic are supsersets of
what is actually needed for 32-bit paging.  PAGE_MASK sets bits 63:12 and
the former GUEST_PT64_BASE_ADDR_MASK sets bits 51:12, so regardless of
which value is used, the result will always be bits 31:12.

No functional change intended.
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220614233328.3896033-9-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

arch/x86/kvm/mmu/mmu.c

@@ -53,8 +53,6 @@
 #include <asm/kvm_page_track.h>
 #include "trace.h"
 
-#include "paging.h"
-
 extern bool itlb_multihit_kvm_mitigation;
 
 int __read_mostly nx_huge_pages = -1;

arch/x86/kvm/mmu/paging.h

-/* SPDX-License-Identifier: GPL-2.0-only */
-/* Shadow paging constants/helpers that don't need to be #undef'd. */
-#ifndef __KVM_X86_PAGING_H
-#define __KVM_X86_PAGING_H
-
-#define GUEST_PT64_BASE_ADDR_MASK (((1ULL << 52) - 1) & ~(u64)(PAGE_SIZE-1))
-
-#endif /* __KVM_X86_PAGING_H */
-

arch/x86/kvm/mmu/paging_tmpl.h

@@ -25,7 +25,6 @@
 	#define pt_element_t u64
 	#define guest_walker guest_walker64
 	#define FNAME(name) paging##64_##name
-	#define PT_BASE_ADDR_MASK GUEST_PT64_BASE_ADDR_MASK
 	#define PT_LEVEL_BITS 9
 	#define PT_GUEST_DIRTY_SHIFT PT_DIRTY_SHIFT
 	#define PT_GUEST_ACCESSED_SHIFT PT_ACCESSED_SHIFT
@@ -39,7 +38,6 @@
 	#define pt_element_t u32
 	#define guest_walker guest_walker32
 	#define FNAME(name) paging##32_##name
-	#define PT_BASE_ADDR_MASK ((pt_element_t)PAGE_MASK)
 	#define PT_LEVEL_BITS 10
 	#define PT_MAX_FULL_LEVELS 2
 	#define PT_GUEST_DIRTY_SHIFT PT_DIRTY_SHIFT
@@ -54,7 +52,6 @@
 	#define pt_element_t u64
 	#define guest_walker guest_walkerEPT
 	#define FNAME(name) ept_##name
-	#define PT_BASE_ADDR_MASK GUEST_PT64_BASE_ADDR_MASK
 	#define PT_LEVEL_BITS 9
 	#define PT_GUEST_DIRTY_SHIFT 9
 	#define PT_GUEST_ACCESSED_SHIFT 8
@@ -65,6 +62,7 @@
 #endif
 
 /* Common logic, but per-type values.  These also need to be undefined. */
+#define PT_BASE_ADDR_MASK	((pt_element_t)(((1ULL << 52) - 1) & ~(u64)(PAGE_SIZE-1)))
 #define PT_LVL_ADDR_MASK(lvl)	__PT_LVL_ADDR_MASK(PT_BASE_ADDR_MASK, lvl, PT_LEVEL_BITS)
 #define PT_LVL_OFFSET_MASK(lvl)	__PT_LVL_OFFSET_MASK(PT_BASE_ADDR_MASK, lvl, PT_LEVEL_BITS)
 #define PT_INDEX(addr, lvl)	__PT_INDEX(addr, lvl, PT_LEVEL_BITS)