On 6/24/22 10:52, Christophe Leroy wrote:
Le 24/06/2022 à 06:43, Anshuman Khandual a écrit :
protection_map[] has already been moved inside those platforms which enable
Usually "already" means before your series.
Your series is the one that moves protection_map[] so I would have just
said "Now that protection_map[] has been moved inside those platforms
which enable ...."
Got it, will update the commit message.
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
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 237828c2bae2..70d900f6df43 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];
Is this declaration still needed ? I have the feeling that
protection_map[] is only used in mm/mmap.c now.
At this point generic protection_map[] array is still being used via
this declaration on many (!ARCH_HAS_VM_GET_PAGE_PROT) platforms such
as mips, m68k, arm etc.
#endif
diff --git a/mm/mmap.c b/mm/mmap.c
index 55c30aee3999..43db3bd49071 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -101,7 +101,7 @@ static void unmap_region(struct mm_struct *mm,
* w: (no) no
* x: (yes) yes
*/
-#ifdef __P000
+#ifndef CONFIG_ARCH_HAS_VM_GET_PAGE_PROT
pgprot_t protection_map[16] __ro_after_init = {
Should this be static, as it seems to now be used only in this file ?
This is being used in some platforms as mentioned before.
And it could also be 'const' instead of __ro_after_init.
Then should be able to be a 'const' wrt mips, m68k, arm platforms.
But should this even be changed, if this is going to be dropped off
eventually ?
[VM_NONE] = __P000,
[VM_READ] = __P001,
@@ -120,9 +120,6 @@ 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 */
