[PATCH 1/4] powerpc/64s: Add DEBUG_PAGEALLOC for radix

@@ -417,6 +417,16 @@ static inline unsigned long pte_pfn(pte_t pte)
 }
 
 /* Generic modifiers for PTE bits */
+static inline pte_t pte_mkabsent(pte_t pte)
+{
+	return __pte(pte_val(pte) & ~_PAGE_PRESENT);
+}
+
+static inline pte_t pte_mkpresent(pte_t pte)
+{
+	return __pte(pte_val(pte) | _PAGE_PRESENT);
+}
+
 static inline pte_t pte_wrprotect(pte_t pte)
 {
 	return __pte(pte_val(pte) & ~_PAGE_RW);

@@ -179,6 +179,8 @@ static inline unsigned long hash__pte_update(struct mm_struct *mm,
 	return old;
 }
 
+void hash__kernel_map_pages(struct page *page, int numpages, int enable);
+
 /* Set the dirty and/or accessed bits atomically in a linux PTE, this
  * function doesn't need to flush the hash entry
  */

@@ -651,6 +651,16 @@ static inline unsigned long pte_pfn(pte_t pte)
 }
 
 /* Generic modifiers for PTE bits */
+static inline pte_t pte_mkabsent(pte_t pte)
+{
+	return __pte_raw(pte_raw(pte) & cpu_to_be64(~_PAGE_PRESENT));
+}
+
+static inline pte_t pte_mkpresent(pte_t pte)
+{
+	return __pte_raw(pte_raw(pte) | cpu_to_be64(_PAGE_PRESENT));
+}
+
 static inline pte_t pte_wrprotect(pte_t pte)
 {
 	if (unlikely(pte_savedwrite(pte)))

@@ -812,6 +822,15 @@ static inline bool check_pte_access(unsigned long access, unsigned long ptev)
  * Generic functions with hash/radix callbacks
  */
 
+#ifdef CONFIG_DEBUG_PAGEALLOC
+static inline void __kernel_map_pages(struct page *page, int numpages, int enable)
+{
+	if (radix_enabled())
+		radix__kernel_map_pages(page, numpages, enable);
+	hash__kernel_map_pages(page, numpages, enable);
+}
+#endif
+
 static inline void __ptep_set_access_flags(struct vm_area_struct *vma,
 					   pte_t *ptep, pte_t entry,
 					   unsigned long address,

@@ -137,6 +137,8 @@ extern void radix__mark_rodata_ro(void);
 extern void radix__mark_initmem_nx(void);
 #endif
 
+void radix__kernel_map_pages(struct page *page, int numpages, int enable);
+
 extern void radix__ptep_set_access_flags(struct vm_area_struct *vma, pte_t *ptep,
 					 pte_t entry, unsigned long address,
 					 int psize);

@@ -125,6 +125,16 @@ static inline unsigned long pte_pfn(pte_t pte)	{
 	return pte_val(pte) >> PTE_RPN_SHIFT; }
 
 /* Generic modifiers for PTE bits */
+static inline pte_t pte_mkabsent(pte_t pte)
+{
+	return __pte(pte_val(pte) & ~_PAGE_PRESENT);
+}
+
+static inline pte_t pte_mkpresent(pte_t pte)
+{
+	return __pte(pte_val(pte) | _PAGE_PRESENT);
+}
+
 static inline pte_t pte_exprotect(pte_t pte)
 {
 	return __pte(pte_val(pte) & ~_PAGE_EXEC);

@@ -6,6 +6,8 @@
 #define SET_MEMORY_RW	1
 #define SET_MEMORY_NX	2
 #define SET_MEMORY_X	3
+#define SET_MEMORY_EN	4
+#define SET_MEMORY_DIS	5
 
 int change_memory_attr(unsigned long addr, int numpages, long action);
 

@@ -1990,7 +1990,7 @@ static void kernel_unmap_linear_page(unsigned long vaddr, unsigned long lmi)
 				     mmu_kernel_ssize, 0);
 }
 
-void __kernel_map_pages(struct page *page, int numpages, int enable)
+void hash__kernel_map_pages(struct page *page, int numpages, int enable)
 {
 	unsigned long flags, vaddr, lmi;
 	int i;

@@ -16,6 +16,7 @@
 #include <linux/hugetlb.h>
 #include <linux/string_helpers.h>
 #include <linux/memory.h>
+#include <linux/set_memory.h>
 
 #include <asm/pgalloc.h>
 #include <asm/mmu_context.h>

@@ -330,9 +331,13 @@ static int __meminit create_physical_mapping(unsigned long start,
 static void __init radix_init_pgtable(void)
 {
 	unsigned long rts_field;
+	unsigned long size = radix_mem_block_size;
 	phys_addr_t start, end;
 	u64 i;
 
+	if (debug_pagealloc_enabled())
+		size = PAGE_SIZE;
+
 	/* We don't support slb for radix */
 	mmu_slb_size = 0;
 

@@ -352,7 +357,7 @@ static void __init radix_init_pgtable(void)
 		}
 
 		WARN_ON(create_physical_mapping(start, end,
-						radix_mem_block_size,
+						size,
 						-1, PAGE_KERNEL));
 	}
 

@@ -872,13 +877,18 @@ int __meminit radix__create_section_mapping(unsigned long start,
 					    unsigned long end, int nid,
 					    pgprot_t prot)
 {
+	unsigned long size = radix_mem_block_size;
+
+	if (debug_pagealloc_enabled())
+		size = PAGE_SIZE;
+
 	if (end >= RADIX_VMALLOC_START) {
 		pr_warn("Outside the supported range\n");
 		return -1;
 	}
 
 	return create_physical_mapping(__pa(start), __pa(end),
-				       radix_mem_block_size, nid, prot);
+				       size, nid, prot);
 }
 
 int __meminit radix__remove_section_mapping(unsigned long start, unsigned long end)

@@ -1165,3 +1175,15 @@ int pmd_free_pte_page(pmd_t *pmd, unsigned long addr)
 
 	return 1;
 }
+
+#ifdef CONFIG_DEBUG_PAGEALLOC
+void radix__kernel_map_pages(struct page *page, int numpages, int enable)
+{
+	unsigned long addr = (unsigned long)page_address(page);
+
+	if (enable)
+		change_memory_attr(addr, numpages, SET_MEMORY_EN);
+	else
+		change_memory_attr(addr, numpages, SET_MEMORY_DIS);
+}
+#endif

@@ -54,6 +54,12 @@ static int change_page_attr(pte_t *ptep, unsigned long addr, void *data)
 	case SET_MEMORY_X:
 		pte = pte_mkexec(pte);
 		break;
+	case SET_MEMORY_DIS:
+		pte = pte_mkabsent(pte);
+		break;
+	case SET_MEMORY_EN:
+		pte = pte_mkpresent(pte);
+		break;
 	default:
 		WARN_ON_ONCE(1);
 		break;