KVM: x86/mmu: Use separate namespaces for guest PTEs and shadow PTEs

Separate the macros for KVM's shadow PTEs (SPTE) from guest 64-bit PTEs
(PT64).  SPTE and PT64 are _mostly_ the same, but the few differences are
quite critical, e.g. *_BASE_ADDR_MASK must differentiate between host and
guest physical address spaces, and SPTE_PERM_MASK (was PT64_PERM_MASK) is
very much specific to SPTEs.

Opportunistically (and temporarily) move most guest macros into paging.h
to clearly associate them with shadow paging, and to ensure that they're
not used as of this commit.  A future patch will eliminate them entirely.

Sadly, PT32_LEVEL_BITS is left behind in mmu_internal.h because it's
needed for the quadrant calculation in kvm_mmu_get_page().  The quadrant
calculation is hot enough (when using shadow paging with 32-bit guests)
that adding a per-context helper is undesirable, and burying the
computation in paging_tmpl.h with a forward declaration isn't exactly an
improvement.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220614233328.3896033-6-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

1 files changed, 12 insertions, 15 deletions

diff --git a/arch/x86/kvm/mmu/spte.h b/arch/x86/kvm/mmu/spte.h
index d5a8183b7232..121c5eaaec77 100644
--- a/arch/x86/kvm/mmu/spte.h
+++ b/arch/x86/kvm/mmu/spte.h
@@ -36,12 +36,12 @@ extern bool __read_mostly enable_mmio_caching;
 static_assert(SPTE_TDP_AD_ENABLED_MASK == 0);
 
 #ifdef CONFIG_DYNAMIC_PHYSICAL_MASK
-#define PT64_BASE_ADDR_MASK (physical_mask & ~(u64)(PAGE_SIZE-1))
+#define SPTE_BASE_ADDR_MASK (physical_mask & ~(u64)(PAGE_SIZE-1))
 #else
-#define PT64_BASE_ADDR_MASK (((1ULL << 52) - 1) & ~(u64)(PAGE_SIZE-1))
+#define SPTE_BASE_ADDR_MASK (((1ULL << 52) - 1) & ~(u64)(PAGE_SIZE-1))
 #endif
 
-#define PT64_PERM_MASK (PT_PRESENT_MASK | PT_WRITABLE_MASK | shadow_user_mask \
+#define SPTE_PERM_MASK (PT_PRESENT_MASK | PT_WRITABLE_MASK | shadow_user_mask \
 			| shadow_x_mask | shadow_nx_mask | shadow_me_mask)
 
 #define ACC_EXEC_MASK    1
@@ -50,16 +50,13 @@ static_assert(SPTE_TDP_AD_ENABLED_MASK == 0);
 #define ACC_ALL          (ACC_EXEC_MASK | ACC_WRITE_MASK | ACC_USER_MASK)
 
 /* The mask for the R/X bits in EPT PTEs */
-#define PT64_EPT_READABLE_MASK			0x1ull
-#define PT64_EPT_EXECUTABLE_MASK		0x4ull
+#define SPTE_EPT_READABLE_MASK			0x1ull
+#define SPTE_EPT_EXECUTABLE_MASK		0x4ull
 
-#define PT64_LEVEL_BITS 9
-
-#define PT64_LEVEL_SHIFT(level) __PT_LEVEL_SHIFT(level, PT64_LEVEL_BITS)
-
-#define PT64_INDEX(address, level) __PT_INDEX(address, level, PT64_LEVEL_BITS)
-
-#define SHADOW_PT_INDEX(addr, level) PT64_INDEX(addr, level)
+#define SPTE_LEVEL_BITS			9
+#define SPTE_LEVEL_SHIFT(level)		__PT_LEVEL_SHIFT(level, SPTE_LEVEL_BITS)
+#define SPTE_INDEX(address, level)	__PT_INDEX(address, level, SPTE_LEVEL_BITS)
+#define SPTE_ENT_PER_PAGE		__PT_ENT_PER_PAGE(SPTE_LEVEL_BITS)
 
 /*
  * The mask/shift to use for saving the original R/X bits when marking the PTE
@@ -68,8 +65,8 @@ static_assert(SPTE_TDP_AD_ENABLED_MASK == 0);
  * restored only when a write is attempted to the page.  This mask obviously
  * must not overlap the A/D type mask.
  */
-#define SHADOW_ACC_TRACK_SAVED_BITS_MASK (PT64_EPT_READABLE_MASK | \
-					  PT64_EPT_EXECUTABLE_MASK)
+#define SHADOW_ACC_TRACK_SAVED_BITS_MASK (SPTE_EPT_READABLE_MASK | \
+					  SPTE_EPT_EXECUTABLE_MASK)
 #define SHADOW_ACC_TRACK_SAVED_BITS_SHIFT 54
 #define SHADOW_ACC_TRACK_SAVED_MASK	(SHADOW_ACC_TRACK_SAVED_BITS_MASK << \
 					 SHADOW_ACC_TRACK_SAVED_BITS_SHIFT)
@@ -281,7 +278,7 @@ static inline bool is_executable_pte(u64 spte)
 
 static inline kvm_pfn_t spte_to_pfn(u64 pte)
 {
-	return (pte & PT64_BASE_ADDR_MASK) >> PAGE_SHIFT;
+	return (pte & SPTE_BASE_ADDR_MASK) >> PAGE_SHIFT;
 }
 
 static inline bool is_accessed_spte(u64 spte)