[PATCH v16 10/25] x86: mm: Add p?d_leaf() definitions

Steven Price
2019-12-06T13:54:16Z

walk_page_range() is going to be allowed to walk page tables other than
those of user space. For this it needs to know when it has reached a
'leaf' entry in the page tables. This information is provided by the
p?d_leaf() functions/macros.

For x86 we already have p?d_large() functions, so simply add macros to
provide the generic p?d_leaf() names for the generic code.

Signed-off-by: Steven Price <steven.price@arm.com>
---
arch/x86/include/asm/pgtable.h | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h
index ad97dc155195..8091a1c62596 100644
--- a/arch/x86/include/asm/pgtable.h
+++ b/arch/x86/include/asm/pgtable.h
@@ -239,6 +239,7 @@ static inline unsigned long pgd_pfn(pgd_t pgd)
return (pgd_val(pgd) & PTE_PFN_MASK) >> PAGE_SHIFT;
}

+#define p4d_leaf p4d_large
static inline int p4d_large(p4d_t p4d)
{
/* No 512 GiB pages yet */
@@ -247,6 +248,7 @@ static inline int p4d_large(p4d_t p4d)

#define pte_page(pte) pfn_to_page(pte_pfn(pte))

+#define pmd_leaf pmd_large
static inline int pmd_large(pmd_t pte)
{
return pmd_flags(pte) & _PAGE_PSE;
@@ -874,6 +876,7 @@ static inline pmd_t *pmd_offset(pud_t *pud, unsigned long address)
return (pmd_t *)pud_page_vaddr(*pud) + pmd_index(address);
}

+#define pud_leaf pud_large
static inline int pud_large(pud_t pud)
{
return (pud_val(pud) & (_PAGE_PSE | _PAGE_PRESENT)) ==
@@ -885,6 +888,7 @@ static inline int pud_bad(pud_t pud)
return (pud_flags(pud) & ~(_KERNPG_TABLE | _PAGE_USER)) != 0;
}
#else
+#define pud_leaf pud_large
static inline int pud_large(pud_t pud)
{
return 0;
@@ -1233,6 +1237,7 @@ static inline bool pgdp_maps_userspace(void *__ptr)
return (((ptr & ~PAGE_MASK) / sizeof(pgd_t)) < PGD_KERNEL_START);
}

+#define pgd_leaf pgd_large
static inline int pgd_large(pgd_t pgd) { return 0; }

#ifdef CONFIG_PAGE_TABLE_ISOLATION
--
2.20.1