[PATCH V6 07/26] mm/mmap: Build protect protection_map[] with ARCH_HAS_VM_GET_PAGE_PROT

From: Anshuman Khandual
Date: Thu Jun 30 2022 - 01:18:43 EST


Now that protection_map[] has been moved inside those platforms that enable
ARCH_HAS_VM_GET_PAGE_PROT. Hence generic protection_map[] array now can be
protected with CONFIG_ARCH_HAS_VM_GET_PAGE_PROT intead of __P000.

Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: linux-mm@xxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
Reviewed-by: Christophe Leroy <christophe.leroy@xxxxxxxxxx>
Signed-off-by: Anshuman Khandual <anshuman.khandual@xxxxxxx>
---
include/linux/mm.h | 2 +-
mm/mmap.c | 5 +----
2 files changed, 2 insertions(+), 5 deletions(-)

diff --git a/include/linux/mm.h b/include/linux/mm.h
index 0ff0a1bad091..07b56995e0fe 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -424,7 +424,7 @@ extern unsigned int kobjsize(const void *objp);
* mapping from the currently active vm_flags protection bits (the
* low four bits) to a page protection mask..
*/
-#ifdef __P000
+#ifndef CONFIG_ARCH_HAS_VM_GET_PAGE_PROT
extern pgprot_t protection_map[16];
#endif

diff --git a/mm/mmap.c b/mm/mmap.c
index b46d5e931bb3..2cc722e162fa 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -81,7 +81,7 @@ static void unmap_region(struct mm_struct *mm,
struct vm_area_struct *vma, struct vm_area_struct *prev,
unsigned long start, unsigned long end);

-#ifdef __P000
+#ifndef CONFIG_ARCH_HAS_VM_GET_PAGE_PROT
pgprot_t protection_map[16] __ro_after_init = {
[VM_NONE] = __P000,
[VM_READ] = __P001,
@@ -100,9 +100,6 @@ pgprot_t protection_map[16] __ro_after_init = {
[VM_SHARED | VM_EXEC | VM_WRITE] = __S110,
[VM_SHARED | VM_EXEC | VM_WRITE | VM_READ] = __S111
};
-#endif
-
-#ifndef CONFIG_ARCH_HAS_VM_GET_PAGE_PROT
DECLARE_VM_GET_PAGE_PROT
#endif /* CONFIG_ARCH_HAS_VM_GET_PAGE_PROT */

--
2.25.1