The patch titled
Subject: um/mm: enable ARCH_HAS_VM_GET_PAGE_PROT
has been added to the -mm mm-unstable branch. Its filename is
um-mm-enable-arch_has_vm_get_page_prot.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/um-mm-enable-arch_has_vm_get_page_prot.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: Anshuman Khandual <anshuman.khandual@xxxxxxx>
Subject: um/mm: enable ARCH_HAS_VM_GET_PAGE_PROT
Date: Thu, 30 Jun 2022 10:46:28 +0530
This enables ARCH_HAS_VM_GET_PAGE_PROT on the platform and exports
standard vm_get_page_prot() implementation via DECLARE_VM_GET_PAGE_PROT,
which looks up a private and static protection_map[] array. Subsequently
all __SXXX and __PXXX macros can be dropped which are no longer needed.
Link: https://lkml.kernel.org/r/20220630051630.1718927-25-anshuman.khandual@xxxxxxx
Signed-off-by: Anshuman Khandual <anshuman.khandual@xxxxxxx>
Cc: Jeff Dike <jdike@xxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
arch/um/Kconfig | 1 +
arch/um/include/asm/pgtable.h | 17 -----------------
arch/um/kernel/mem.c | 20 ++++++++++++++++++++
arch/x86/um/mem_32.c | 2 +-
4 files changed, 22 insertions(+), 18 deletions(-)
--- a/arch/um/include/asm/pgtable.h~um-mm-enable-arch_has_vm_get_page_prot
+++ a/arch/um/include/asm/pgtable.h
@@ -68,23 +68,6 @@ extern unsigned long end_iomem;
* Also, write permissions imply read permissions. This is the closest we can
* get..
*/
-#define __P000 PAGE_NONE
-#define __P001 PAGE_READONLY
-#define __P010 PAGE_COPY
-#define __P011 PAGE_COPY
-#define __P100 PAGE_READONLY
-#define __P101 PAGE_READONLY
-#define __P110 PAGE_COPY
-#define __P111 PAGE_COPY
-
-#define __S000 PAGE_NONE
-#define __S001 PAGE_READONLY
-#define __S010 PAGE_SHARED
-#define __S011 PAGE_SHARED
-#define __S100 PAGE_READONLY
-#define __S101 PAGE_READONLY
-#define __S110 PAGE_SHARED
-#define __S111 PAGE_SHARED
/*
* ZERO_PAGE is a global shared page that is always zero: used
--- a/arch/um/Kconfig~um-mm-enable-arch_has_vm_get_page_prot
+++ a/arch/um/Kconfig
@@ -10,6 +10,7 @@ config UML
select ARCH_HAS_KCOV
select ARCH_HAS_STRNCPY_FROM_USER
select ARCH_HAS_STRNLEN_USER
+ select ARCH_HAS_VM_GET_PAGE_PROT
select ARCH_NO_PREEMPT
select HAVE_ARCH_AUDITSYSCALL
select HAVE_ARCH_SECCOMP_FILTER
--- a/arch/um/kernel/mem.c~um-mm-enable-arch_has_vm_get_page_prot
+++ a/arch/um/kernel/mem.c
@@ -197,3 +197,23 @@ void *uml_kmalloc(int size, int flags)
{
return kmalloc(size, flags);
}
+
+static const pgprot_t protection_map[16] = {
+ [VM_NONE] = PAGE_NONE,
+ [VM_READ] = PAGE_READONLY,
+ [VM_WRITE] = PAGE_COPY,
+ [VM_WRITE | VM_READ] = PAGE_COPY,
+ [VM_EXEC] = PAGE_READONLY,
+ [VM_EXEC | VM_READ] = PAGE_READONLY,
+ [VM_EXEC | VM_WRITE] = PAGE_COPY,
+ [VM_EXEC | VM_WRITE | VM_READ] = PAGE_COPY,
+ [VM_SHARED] = PAGE_NONE,
+ [VM_SHARED | VM_READ] = PAGE_READONLY,
+ [VM_SHARED | VM_WRITE] = PAGE_SHARED,
+ [VM_SHARED | VM_WRITE | VM_READ] = PAGE_SHARED,
+ [VM_SHARED | VM_EXEC] = PAGE_READONLY,
+ [VM_SHARED | VM_EXEC | VM_READ] = PAGE_READONLY,
+ [VM_SHARED | VM_EXEC | VM_WRITE] = PAGE_SHARED,
+ [VM_SHARED | VM_EXEC | VM_WRITE | VM_READ] = PAGE_SHARED
+};
+DECLARE_VM_GET_PAGE_PROT
--- a/arch/x86/um/mem_32.c~um-mm-enable-arch_has_vm_get_page_prot
+++ a/arch/x86/um/mem_32.c
@@ -17,7 +17,7 @@ static int __init gate_vma_init(void)
gate_vma.vm_start = FIXADDR_USER_START;
gate_vma.vm_end = FIXADDR_USER_END;
gate_vma.vm_flags = VM_READ | VM_MAYREAD | VM_EXEC | VM_MAYEXEC;
- gate_vma.vm_page_prot = __P101;
+ gate_vma.vm_page_prot = PAGE_READONLY;
return 0;
}
_
Patches currently in -mm which might be from anshuman.khandual@xxxxxxx are
mm-mmap-build-protect-protection_map-with-__p000.patch
mm-mmap-define-declare_vm_get_page_prot.patch
powerpc-mm-move-protection_map-inside-the-platform.patch
sparc-mm-move-protection_map-inside-the-platform.patch
arm64-mm-move-protection_map-inside-the-platform.patch
x86-mm-move-protection_map-inside-the-platform.patch
mm-mmap-build-protect-protection_map-with-arch_has_vm_get_page_prot.patch
microblaze-mm-enable-arch_has_vm_get_page_prot.patch
loongarch-mm-enable-arch_has_vm_get_page_prot.patch
openrisc-mm-enable-arch_has_vm_get_page_prot.patch
xtensa-mm-enable-arch_has_vm_get_page_prot.patch
hexagon-mm-enable-arch_has_vm_get_page_prot.patch
parisc-mm-enable-arch_has_vm_get_page_prot.patch
alpha-mm-enable-arch_has_vm_get_page_prot.patch
nios2-mm-enable-arch_has_vm_get_page_prot.patch
riscv-mm-enable-arch_has_vm_get_page_prot.patch
csky-mm-enable-arch_has_vm_get_page_prot.patch
s390-mm-enable-arch_has_vm_get_page_prot.patch
ia64-mm-enable-arch_has_vm_get_page_prot.patch
mips-mm-enable-arch_has_vm_get_page_prot.patch
m68k-mm-enable-arch_has_vm_get_page_prot.patch
arc-mm-enable-arch_has_vm_get_page_prot.patch
arm-mm-enable-arch_has_vm_get_page_prot.patch
um-mm-enable-arch_has_vm_get_page_prot.patch
sh-mm-enable-arch_has_vm_get_page_prot.patch
mm-mmap-drop-arch_has_vm_get_page_prot.patch
