powerpc/mm: Add radix pgalloc details

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

arch/powerpc/include/asm/book3s/64/pgalloc.h

@@ -50,19 +50,45 @@ extern void pgtable_free_tlb(struct mmu_gather *tlb, void *table, int shift);
 extern void __tlb_remove_table(void *_table);
 #endif
 
+static inline pgd_t *radix__pgd_alloc(struct mm_struct *mm)
+{
+#ifdef CONFIG_PPC_64K_PAGES
+	return (pgd_t *)__get_free_page(PGALLOC_GFP);
+#else
+	struct page *page;
+	page = alloc_pages(PGALLOC_GFP, 4);
+	if (!page)
+		return NULL;
+	return (pgd_t *) page_address(page);
+#endif
+}
+
+static inline void radix__pgd_free(struct mm_struct *mm, pgd_t *pgd)
+{
+#ifdef CONFIG_PPC_64K_PAGES
+	free_page((unsigned long)pgd);
+#else
+	free_pages((unsigned long)pgd, 4);
+#endif
+}
+
 static inline pgd_t *pgd_alloc(struct mm_struct *mm)
 {
+	if (radix_enabled())
+		return radix__pgd_alloc(mm);
 	return kmem_cache_alloc(PGT_CACHE(PGD_INDEX_SIZE), GFP_KERNEL);
 }
 
 static inline void pgd_free(struct mm_struct *mm, pgd_t *pgd)
 {
+	if (radix_enabled())
+		return radix__pgd_free(mm, pgd);
 	kmem_cache_free(PGT_CACHE(PGD_INDEX_SIZE), pgd);
 }
 
 static inline void pgd_populate(struct mm_struct *mm, pgd_t *pgd, pud_t *pud)
 {
-	pgd_set(pgd, __pgtable_ptr_val(pud));
+	pgd_set(pgd, __pgtable_ptr_val(pud) | PGD_VAL_BITS);
 }
 
 static inline pud_t *pud_alloc_one(struct mm_struct *mm, unsigned long addr)
@@ -78,7 +104,7 @@ static inline void pud_free(struct mm_struct *mm, pud_t *pud)
 
 static inline void pud_populate(struct mm_struct *mm, pud_t *pud, pmd_t *pmd)
 {
-	pud_set(pud, __pgtable_ptr_val(pmd));
+	pud_set(pud, __pgtable_ptr_val(pmd) | PUD_VAL_BITS);
 }
 
 static inline void __pud_free_tlb(struct mmu_gather *tlb, pud_t *pud,
@@ -107,13 +133,13 @@ static inline void __pmd_free_tlb(struct mmu_gather *tlb, pmd_t *pmd,
 static inline void pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmd,
 				       pte_t *pte)
 {
-	pmd_set(pmd, __pgtable_ptr_val(pte));
+	pmd_set(pmd, __pgtable_ptr_val(pte) | PMD_VAL_BITS);
 }
 
 static inline void pmd_populate(struct mm_struct *mm, pmd_t *pmd,
 				pgtable_t pte_page)
 {
-	pmd_set(pmd, __pgtable_ptr_val(pte_page));
+	pmd_set(pmd, __pgtable_ptr_val(pte_page) | PMD_VAL_BITS);
 }
 
 static inline pgtable_t pmd_pgtable(pmd_t pmd)

arch/powerpc/include/asm/book3s/64/pgtable.h

@@ -170,11 +170,17 @@ extern unsigned long __pgd_table_size;
 #define PMD_TABLE_SIZE	__pmd_table_size
 #define PUD_TABLE_SIZE	__pud_table_size
 #define PGD_TABLE_SIZE	__pgd_table_size
+
+extern unsigned long __pmd_val_bits;
+extern unsigned long __pud_val_bits;
+extern unsigned long __pgd_val_bits;
+#define PMD_VAL_BITS	__pmd_val_bits
+#define PUD_VAL_BITS	__pud_val_bits
+#define PGD_VAL_BITS	__pgd_val_bits
 /*
  * Pgtable size used by swapper, init in asm code
- * We will switch this later to radix PGD
  */
-#define MAX_PGD_TABLE_SIZE (sizeof(pgd_t) << H_PGD_INDEX_SIZE)
+#define MAX_PGD_TABLE_SIZE (sizeof(pgd_t) << RADIX_PGD_INDEX_SIZE)
 
 #define PTRS_PER_PTE	(1 << PTE_INDEX_SIZE)
 #define PTRS_PER_PMD	(1 << PMD_INDEX_SIZE)

arch/powerpc/mm/hash_utils_64.c

@@ -882,6 +882,13 @@ void __init hash__early_init_mmu(void)
 	__pmd_table_size = H_PMD_TABLE_SIZE;
 	__pud_table_size = H_PUD_TABLE_SIZE;
 	__pgd_table_size = H_PGD_TABLE_SIZE;
+	/*
+	 * 4k use hugepd format, so for hash set then to
+	 * zero
+	 */
+	__pmd_val_bits = 0;
+	__pud_val_bits = 0;
+	__pgd_val_bits = 0;
 	/* Initialize the MMU Hash table and create the linear mapping
 	 * of memory. Has to be done before SLB initialization as this is
 	 * currently where the page size encoding is obtained.

arch/powerpc/mm/pgtable-radix.c

@@ -324,8 +324,11 @@ void __init radix__early_init_mmu(void)
 	__pud_table_size = RADIX_PUD_TABLE_SIZE;
 	__pgd_table_size = RADIX_PGD_TABLE_SIZE;
 
-	radix_init_page_sizes();
+	__pmd_val_bits = RADIX_PMD_VAL_BITS;
+	__pud_val_bits = RADIX_PUD_VAL_BITS;
+	__pgd_val_bits = RADIX_PGD_VAL_BITS;
 
+	radix_init_page_sizes();
 	if (!firmware_has_feature(FW_FEATURE_LPAR))
 		radix_init_partition_table();
 

arch/powerpc/mm/pgtable_64.c

@@ -91,6 +91,12 @@ unsigned long __pud_table_size;
 EXPORT_SYMBOL(__pud_table_size);
 unsigned long __pgd_table_size;
 EXPORT_SYMBOL(__pgd_table_size);
+unsigned long __pmd_val_bits;
+EXPORT_SYMBOL(__pmd_val_bits);
+unsigned long __pud_val_bits;
+EXPORT_SYMBOL(__pud_val_bits);
+unsigned long __pgd_val_bits;
+EXPORT_SYMBOL(__pgd_val_bits);
 
 #endif
 unsigned long ioremap_bot = IOREMAP_BASE;