x86/mm: Stop pretending pgtable_l5_enabled is a variable

pgtable_l5_enabled is defined using cpu_feature_enabled() but we refer
to it as a variable. This is misleading.

Make pgtable_l5_enabled() a function.

We cannot literally define it as a function due to circular dependencies
between header files. Function-alike macros is close enough.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20180518103528.59260-4-kirill.shutemov@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

8 files changed, 23 insertions, 19 deletions

diff --git a/arch/x86/include/asm/page_64_types.h b/arch/x86/include/asm/page_64_types.h
index 2c5a966dc222..6afac386a434 100644
--- a/arch/x86/include/asm/page_64_types.h
+++ b/arch/x86/include/asm/page_64_types.h
@@ -53,7 +53,7 @@
 #define __PHYSICAL_MASK_SHIFT	52
 
 #ifdef CONFIG_X86_5LEVEL
-#define __VIRTUAL_MASK_SHIFT	(pgtable_l5_enabled ? 56 : 47)
+#define __VIRTUAL_MASK_SHIFT	(pgtable_l5_enabled() ? 56 : 47)
 #else
 #define __VIRTUAL_MASK_SHIFT	47
 #endif
diff --git a/arch/x86/include/asm/paravirt.h b/arch/x86/include/asm/paravirt.h
index 9be2bf13825b..d49bbf4bb5c8 100644
--- a/arch/x86/include/asm/paravirt.h
+++ b/arch/x86/include/asm/paravirt.h
@@ -574,14 +574,14 @@ static inline void __set_pgd(pgd_t *pgdp, pgd_t pgd)
 }
 
 #define set_pgd(pgdp, pgdval) do {					\
-	if (pgtable_l5_enabled)						\
+	if (pgtable_l5_enabled())						\
 		__set_pgd(pgdp, pgdval);				\
 	else								\
 		set_p4d((p4d_t *)(pgdp), (p4d_t) { (pgdval).pgd });	\
 } while (0)
 
 #define pgd_clear(pgdp) do {						\
-	if (pgtable_l5_enabled)						\
+	if (pgtable_l5_enabled())						\
 		set_pgd(pgdp, __pgd(0));				\
 } while (0)
 
diff --git a/arch/x86/include/asm/pgalloc.h b/arch/x86/include/asm/pgalloc.h
index 263c142a6a6c..ada6410fd2ec 100644
--- a/arch/x86/include/asm/pgalloc.h
+++ b/arch/x86/include/asm/pgalloc.h
@@ -167,7 +167,7 @@ static inline void __pud_free_tlb(struct mmu_gather *tlb, pud_t *pud,
 #if CONFIG_PGTABLE_LEVELS > 4
 static inline void pgd_populate(struct mm_struct *mm, pgd_t *pgd, p4d_t *p4d)
 {
-	if (!pgtable_l5_enabled)
+	if (!pgtable_l5_enabled())
 		return;
 	paravirt_alloc_p4d(mm, __pa(p4d) >> PAGE_SHIFT);
 	set_pgd(pgd, __pgd(_PAGE_TABLE | __pa(p4d)));
@@ -193,7 +193,7 @@ extern void ___p4d_free_tlb(struct mmu_gather *tlb, p4d_t *p4d);
 static inline void __p4d_free_tlb(struct mmu_gather *tlb, p4d_t *p4d,
 				  unsigned long address)
 {
-	if (pgtable_l5_enabled)
+	if (pgtable_l5_enabled())
 		___p4d_free_tlb(tlb, p4d);
 }
 
diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h
index f1633de5a675..5715647fc4fe 100644
--- a/arch/x86/include/asm/pgtable.h
+++ b/arch/x86/include/asm/pgtable.h
@@ -65,7 +65,7 @@ extern pmdval_t early_pmd_flags;
 
 #ifndef __PAGETABLE_P4D_FOLDED
 #define set_pgd(pgdp, pgd)		native_set_pgd(pgdp, pgd)
-#define pgd_clear(pgd)			(pgtable_l5_enabled ? native_pgd_clear(pgd) : 0)
+#define pgd_clear(pgd)			(pgtable_l5_enabled() ? native_pgd_clear(pgd) : 0)
 #endif
 
 #ifndef set_p4d
@@ -881,7 +881,7 @@ static inline unsigned long p4d_index(unsigned long address)
 #if CONFIG_PGTABLE_LEVELS > 4
 static inline int pgd_present(pgd_t pgd)
 {
-	if (!pgtable_l5_enabled)
+	if (!pgtable_l5_enabled())
 		return 1;
 	return pgd_flags(pgd) & _PAGE_PRESENT;
 }
@@ -900,7 +900,7 @@ static inline unsigned long pgd_page_vaddr(pgd_t pgd)
 /* to find an entry in a page-table-directory. */
 static inline p4d_t *p4d_offset(pgd_t *pgd, unsigned long address)
 {
-	if (!pgtable_l5_enabled)
+	if (!pgtable_l5_enabled())
 		return (p4d_t *)pgd;
 	return (p4d_t *)pgd_page_vaddr(*pgd) + p4d_index(address);
 }
@@ -909,7 +909,7 @@ static inline int pgd_bad(pgd_t pgd)
 {
 	unsigned long ignore_flags = _PAGE_USER;
 
-	if (!pgtable_l5_enabled)
+	if (!pgtable_l5_enabled())
 		return 0;
 
 	if (IS_ENABLED(CONFIG_PAGE_TABLE_ISOLATION))
@@ -920,7 +920,7 @@ static inline int pgd_bad(pgd_t pgd)
 
 static inline int pgd_none(pgd_t pgd)
 {
-	if (!pgtable_l5_enabled)
+	if (!pgtable_l5_enabled())
 		return 0;
 	/*
 	 * There is no need to do a workaround for the KNL stray
diff --git a/arch/x86/include/asm/pgtable_32_types.h b/arch/x86/include/asm/pgtable_32_types.h
index e3225e83db7d..d9a001a4a872 100644
--- a/arch/x86/include/asm/pgtable_32_types.h
+++ b/arch/x86/include/asm/pgtable_32_types.h
@@ -15,7 +15,7 @@
 # include <asm/pgtable-2level_types.h>
 #endif
 
-#define pgtable_l5_enabled 0
+#define pgtable_l5_enabled() 0
 
 #define PGDIR_SIZE	(1UL << PGDIR_SHIFT)
 #define PGDIR_MASK	(~(PGDIR_SIZE - 1))
diff --git a/arch/x86/include/asm/pgtable_64.h b/arch/x86/include/asm/pgtable_64.h
index 877bc27718ae..3c5385f9a88f 100644
--- a/arch/x86/include/asm/pgtable_64.h
+++ b/arch/x86/include/asm/pgtable_64.h
@@ -220,7 +220,7 @@ static inline void native_set_p4d(p4d_t *p4dp, p4d_t p4d)
 {
 	pgd_t pgd;
 
-	if (pgtable_l5_enabled || !IS_ENABLED(CONFIG_PAGE_TABLE_ISOLATION)) {
+	if (pgtable_l5_enabled() || !IS_ENABLED(CONFIG_PAGE_TABLE_ISOLATION)) {
 		*p4dp = p4d;
 		return;
 	}
diff --git a/arch/x86/include/asm/pgtable_64_types.h b/arch/x86/include/asm/pgtable_64_types.h
index c14a4116a693..054765ab2da2 100644
--- a/arch/x86/include/asm/pgtable_64_types.h
+++ b/arch/x86/include/asm/pgtable_64_types.h
@@ -28,12 +28,16 @@ extern unsigned int __pgtable_l5_enabled;
  * cpu_feature_enabled() is not available in early boot code.
  * Use variable instead.
  */
-#define pgtable_l5_enabled __pgtable_l5_enabled
+static inline bool pgtable_l5_enabled(void)
+{
+	return __pgtable_l5_enabled;
+}
 #else
-#define pgtable_l5_enabled cpu_feature_enabled(X86_FEATURE_LA57)
+#define pgtable_l5_enabled() cpu_feature_enabled(X86_FEATURE_LA57)
 #endif /* USE_EARLY_PGTABLE_L5 */
+
 #else
-#define pgtable_l5_enabled 0
+#define pgtable_l5_enabled() 0
 #endif /* CONFIG_X86_5LEVEL */
 
 extern unsigned int pgdir_shift;
@@ -109,7 +113,7 @@ extern unsigned int ptrs_per_p4d;
 
 #define LDT_PGD_ENTRY_L4	-3UL
 #define LDT_PGD_ENTRY_L5	-112UL
-#define LDT_PGD_ENTRY		(pgtable_l5_enabled ? LDT_PGD_ENTRY_L5 : LDT_PGD_ENTRY_L4)
+#define LDT_PGD_ENTRY		(pgtable_l5_enabled() ? LDT_PGD_ENTRY_L5 : LDT_PGD_ENTRY_L4)
 #define LDT_BASE_ADDR		(LDT_PGD_ENTRY << PGDIR_SHIFT)
 
 #define __VMALLOC_BASE_L4	0xffffc90000000000UL
@@ -123,7 +127,7 @@ extern unsigned int ptrs_per_p4d;
 
 #ifdef CONFIG_DYNAMIC_MEMORY_LAYOUT
 # define VMALLOC_START		vmalloc_base
-# define VMALLOC_SIZE_TB	(pgtable_l5_enabled ? VMALLOC_SIZE_TB_L5 : VMALLOC_SIZE_TB_L4)
+# define VMALLOC_SIZE_TB	(pgtable_l5_enabled() ? VMALLOC_SIZE_TB_L5 : VMALLOC_SIZE_TB_L4)
 # define VMEMMAP_START		vmemmap_base
 #else
 # define VMALLOC_START		__VMALLOC_BASE_L4
diff --git a/arch/x86/include/asm/sparsemem.h b/arch/x86/include/asm/sparsemem.h
index 4617a2bf123c..199218719a86 100644
--- a/arch/x86/include/asm/sparsemem.h
+++ b/arch/x86/include/asm/sparsemem.h
@@ -27,8 +27,8 @@
 # endif
 #else /* CONFIG_X86_32 */
 # define SECTION_SIZE_BITS	27 /* matt - 128 is convenient right now */
-# define MAX_PHYSADDR_BITS	(pgtable_l5_enabled ? 52 : 44)
-# define MAX_PHYSMEM_BITS	(pgtable_l5_enabled ? 52 : 46)
+# define MAX_PHYSADDR_BITS	(pgtable_l5_enabled() ? 52 : 44)
+# define MAX_PHYSMEM_BITS	(pgtable_l5_enabled() ? 52 : 46)
 #endif
 
 #endif /* CONFIG_SPARSEMEM */