x86: expose number of page table levels on Kconfig level

We would want to use number of page table level to define mm_struct.
Let's expose it as CONFIG_PGTABLE_LEVELS.

Signed-off-by: Kirill A. Shutemov <[e-mail]>
Cc: Thomas Gleixner <[e-mail]>
Cc: Ingo Molnar <[e-mail]>
Cc: "H. Peter Anvin" <[e-mail]>
Tested-by: Guenter Roeck <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

arch/x86/Kconfig

···
 config FIX_EARLYCON_MEM
 	def_bool y
 
+config PGTABLE_LEVELS
+	int
+	default 4 if X86_64
+	default 3 if X86_PAE
+	default 2
+
 source "init/Kconfig"
 source "kernel/Kconfig.freezer"
 

arch/x86/include/asm/paravirt.h

···
 		PVOP_VCALL2(pv_mmu_ops.set_pmd, pmdp, val);
 }
 
-#if PAGETABLE_LEVELS >= 3
+#if CONFIG_PGTABLE_LEVELS >= 3
 static inline pmd_t __pmd(pmdval_t val)
 {
 	pmdval_t ret;
···
 		PVOP_VCALL2(pv_mmu_ops.set_pud, pudp,
 			    val);
 }
-#if PAGETABLE_LEVELS == 4
+#if CONFIG_PGTABLE_LEVELS == 4
 static inline pud_t __pud(pudval_t val)
 {
 	pudval_t ret;
···
 	set_pud(pudp, __pud(0));
 }
 
-#endif	/* PAGETABLE_LEVELS == 4 */
+#endif	/* CONFIG_PGTABLE_LEVELS == 4 */
 
-#endif	/* PAGETABLE_LEVELS >= 3 */
+#endif	/* CONFIG_PGTABLE_LEVELS >= 3 */
 
 #ifdef CONFIG_X86_PAE
 /* Special-case pte-setting operations for PAE, which can't update a

arch/x86/include/asm/paravirt_types.h

···
 	struct paravirt_callee_save pgd_val;
 	struct paravirt_callee_save make_pgd;
 
-#if PAGETABLE_LEVELS >= 3
+#if CONFIG_PGTABLE_LEVELS >= 3
 #ifdef CONFIG_X86_PAE
 	void (*set_pte_atomic)(pte_t *ptep, pte_t pteval);
 	void (*pte_clear)(struct mm_struct *mm, unsigned long addr,
···
 	struct paravirt_callee_save pmd_val;
 	struct paravirt_callee_save make_pmd;
 
-#if PAGETABLE_LEVELS == 4
+#if CONFIG_PGTABLE_LEVELS == 4
 	struct paravirt_callee_save pud_val;
 	struct paravirt_callee_save make_pud;
 
 	void (*set_pgd)(pgd_t *pudp, pgd_t pgdval);
-#endif	/* PAGETABLE_LEVELS == 4 */
-#endif	/* PAGETABLE_LEVELS >= 3 */
+#endif	/* CONFIG_PGTABLE_LEVELS == 4 */
+#endif	/* CONFIG_PGTABLE_LEVELS >= 3 */
 
 	struct pv_lazy_ops lazy_mode;
 

arch/x86/include/asm/pgalloc.h

···
 
 #define pmd_pgtable(pmd) pmd_page(pmd)
 
-#if PAGETABLE_LEVELS > 2
+#if CONFIG_PGTABLE_LEVELS > 2
 static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long addr)
 {
 	struct page *page;
···
 }
 #endif	/* CONFIG_X86_PAE */
 
-#if PAGETABLE_LEVELS > 3
+#if CONFIG_PGTABLE_LEVELS > 3
 static inline void pgd_populate(struct mm_struct *mm, pgd_t *pgd, pud_t *pud)
 {
 	paravirt_alloc_pud(mm, __pa(pud) >> PAGE_SHIFT);
···
 	___pud_free_tlb(tlb, pud);
 }
 
-#endif	/* PAGETABLE_LEVELS > 3 */
-#endif	/* PAGETABLE_LEVELS > 2 */
+#endif	/* CONFIG_PGTABLE_LEVELS > 3 */
+#endif	/* CONFIG_PGTABLE_LEVELS > 2 */
 
 #endif /* _ASM_X86_PGALLOC_H */

arch/x86/include/asm/pgtable-2level_types.h

···
 #endif	/* !__ASSEMBLY__ */
 
 #define SHARED_KERNEL_PMD	0
-#define PAGETABLE_LEVELS	2
 
 /*
  * traditional i386 two-level paging structure:

arch/x86/include/asm/pgtable-3level_types.h

···
 #define SHARED_KERNEL_PMD	1
 #endif
 
-#define PAGETABLE_LEVELS	3
-
 /*
  * PGDIR_SHIFT determines what a top-level page table entry can map
  */

arch/x86/include/asm/pgtable.h

···
 	return npg >> (20 - PAGE_SHIFT);
 }
 
-#if PAGETABLE_LEVELS > 2
+#if CONFIG_PGTABLE_LEVELS > 2
 static inline int pud_none(pud_t pud)
 {
 	return native_pud_val(pud) == 0;
···
 {
 	return 0;
 }
-#endif	/* PAGETABLE_LEVELS > 2 */
+#endif	/* CONFIG_PGTABLE_LEVELS > 2 */
 
-#if PAGETABLE_LEVELS > 3
+#if CONFIG_PGTABLE_LEVELS > 3
 static inline int pgd_present(pgd_t pgd)
 {
 	return pgd_flags(pgd) & _PAGE_PRESENT;
···
 {
 	return !native_pgd_val(pgd);
 }
-#endif	/* PAGETABLE_LEVELS > 3 */
+#endif	/* CONFIG_PGTABLE_LEVELS > 3 */
 
 #endif	/* __ASSEMBLY__ */
 

arch/x86/include/asm/pgtable_64_types.h

···
 #endif	/* !__ASSEMBLY__ */
 
 #define SHARED_KERNEL_PMD	0
-#define PAGETABLE_LEVELS	4
 
 /*
  * PGDIR_SHIFT determines what a top-level page table entry can map

arch/x86/include/asm/pgtable_types.h

···
 	return native_pgd_val(pgd) & PTE_FLAGS_MASK;
 }
 
-#if PAGETABLE_LEVELS > 3
+#if CONFIG_PGTABLE_LEVELS > 3
 typedef struct { pudval_t pud; } pud_t;
 
 static inline pud_t native_make_pud(pmdval_t val)
···
 }
 #endif
 
-#if PAGETABLE_LEVELS > 2
+#if CONFIG_PGTABLE_LEVELS > 2
 typedef struct { pmdval_t pmd; } pmd_t;
 
 static inline pmd_t native_make_pmd(pmdval_t val)

arch/x86/kernel/paravirt.c

···
 	.ptep_modify_prot_start = __ptep_modify_prot_start,
 	.ptep_modify_prot_commit = __ptep_modify_prot_commit,
 
-#if PAGETABLE_LEVELS >= 3
+#if CONFIG_PGTABLE_LEVELS >= 3
 #ifdef CONFIG_X86_PAE
 	.set_pte_atomic = native_set_pte_atomic,
 	.pte_clear = native_pte_clear,
···
 	.pmd_val = PTE_IDENT,
 	.make_pmd = PTE_IDENT,
 
-#if PAGETABLE_LEVELS == 4
+#if CONFIG_PGTABLE_LEVELS == 4
 	.pud_val = PTE_IDENT,
 	.make_pud = PTE_IDENT,
 
 	.set_pgd = native_set_pgd,
 #endif
-#endif /* PAGETABLE_LEVELS >= 3 */
+#endif /* CONFIG_PGTABLE_LEVELS >= 3 */
 
 	.pte_val = PTE_IDENT,
 	.pgd_val = PTE_IDENT,

arch/x86/mm/pgtable.c

···
 	tlb_remove_page(tlb, pte);
 }
 
-#if PAGETABLE_LEVELS > 2
+#if CONFIG_PGTABLE_LEVELS > 2
 void ___pmd_free_tlb(struct mmu_gather *tlb, pmd_t *pmd)
 {
 	struct page *page = virt_to_page(pmd);
···
 	tlb_remove_page(tlb, page);
 }
 
-#if PAGETABLE_LEVELS > 3
+#if CONFIG_PGTABLE_LEVELS > 3
 void ___pud_free_tlb(struct mmu_gather *tlb, pud_t *pud)
 {
 	paravirt_release_pud(__pa(pud) >> PAGE_SHIFT);
 	tlb_remove_page(tlb, virt_to_page(pud));
 }
-#endif	/* PAGETABLE_LEVELS > 3 */
-#endif	/* PAGETABLE_LEVELS > 2 */
+#endif	/* CONFIG_PGTABLE_LEVELS > 3 */
+#endif	/* CONFIG_PGTABLE_LEVELS > 2 */
 
 static inline void pgd_list_add(pgd_t *pgd)
 {
···
 	/* If the pgd points to a shared pagetable level (either the
 	   ptes in non-PAE, or shared PMD in PAE), then just copy the
 	   references from swapper_pg_dir. */
-	if (PAGETABLE_LEVELS == 2 ||
-	    (PAGETABLE_LEVELS == 3 && SHARED_KERNEL_PMD) ||
-	    PAGETABLE_LEVELS == 4) {
+	if (CONFIG_PGTABLE_LEVELS == 2 ||
+	    (CONFIG_PGTABLE_LEVELS == 3 && SHARED_KERNEL_PMD) ||
+	    CONFIG_PGTABLE_LEVELS == 4) {
 		clone_pgd_range(pgd + KERNEL_PGD_BOUNDARY,
 				swapper_pg_dir + KERNEL_PGD_BOUNDARY,
 				KERNEL_PGD_PTRS);

arch/x86/xen/mmu.c

···
 }
 PV_CALLEE_SAVE_REGS_THUNK(xen_make_pmd);
 
-#if PAGETABLE_LEVELS == 4
+#if CONFIG_PGTABLE_LEVELS == 4
 __visible pudval_t xen_pud_val(pud_t pud)
 {
 	return pte_mfn_to_pfn(pud.pud);
···
 
 	xen_mc_issue(PARAVIRT_LAZY_MMU);
 }
-#endif	/* PAGETABLE_LEVELS == 4 */
+#endif	/* CONFIG_PGTABLE_LEVELS == 4 */
 
 /*
  * (Yet another) pagetable walker.  This one is intended for pinning a
···
 	xen_release_ptpage(pfn, PT_PMD);
 }
 
-#if PAGETABLE_LEVELS == 4
+#if CONFIG_PGTABLE_LEVELS == 4
 static void xen_alloc_pud(struct mm_struct *mm, unsigned long pfn)
 {
 	xen_alloc_ptpage(mm, pfn, PT_PUD);
···
 	pv_mmu_ops.set_pte = xen_set_pte;
 	pv_mmu_ops.set_pmd = xen_set_pmd;
 	pv_mmu_ops.set_pud = xen_set_pud;
-#if PAGETABLE_LEVELS == 4
+#if CONFIG_PGTABLE_LEVELS == 4
 	pv_mmu_ops.set_pgd = xen_set_pgd;
 #endif
 
···
 	pv_mmu_ops.alloc_pmd = xen_alloc_pmd;
 	pv_mmu_ops.release_pte = xen_release_pte;
 	pv_mmu_ops.release_pmd = xen_release_pmd;
-#if PAGETABLE_LEVELS == 4
+#if CONFIG_PGTABLE_LEVELS == 4
 	pv_mmu_ops.alloc_pud = xen_alloc_pud;
 	pv_mmu_ops.release_pud = xen_release_pud;
 #endif
···
 	.make_pmd = PV_CALLEE_SAVE(xen_make_pmd),
 	.pmd_val = PV_CALLEE_SAVE(xen_pmd_val),
 
-#if PAGETABLE_LEVELS == 4
+#if CONFIG_PGTABLE_LEVELS == 4
 	.pud_val = PV_CALLEE_SAVE(xen_pud_val),
 	.make_pud = PV_CALLEE_SAVE(xen_make_pud),
 	.set_pgd = xen_set_pgd_hyper,
 
 	.alloc_pud = xen_alloc_pmd_init,
 	.release_pud = xen_release_pmd_init,
-#endif	/* PAGETABLE_LEVELS == 4 */
+#endif	/* CONFIG_PGTABLE_LEVELS == 4 */
 
 	.activate_mm = xen_activate_mm,
 	.dup_mmap = xen_dup_mmap,

include/trace/events/xen.h

···
 	    TP_printk("pmdp %p", __entry->pmdp)
 	);
 
-#if PAGETABLE_LEVELS >= 4
+#if CONFIG_PGTABLE_LEVELS >= 4
 
 TRACE_EVENT(xen_mmu_set_pud,
 	    TP_PROTO(pud_t *pudp, pud_t pudval),