[PATCH V3 21/30] parisc/mm: Enable ARCH_HAS_VM_GET_PAGE_PROT

Anshuman Khandual
2022-02-28T10:54:08Z

This defines and exports a platform specific custom vm_get_page_prot() via
subscribing ARCH_HAS_VM_GET_PAGE_PROT. Subsequently all __SXXX and __PXXX
macros can be dropped which are no longer needed.

Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: linux-parisc@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
---
arch/parisc/Kconfig | 1 +
arch/parisc/include/asm/pgtable.h | 20 ----------------
arch/parisc/mm/init.c | 40 +++++++++++++++++++++++++++++++
3 files changed, 41 insertions(+), 20 deletions(-)

diff --git a/arch/parisc/Kconfig b/arch/parisc/Kconfig
index 43c1c880def6..de512f120b50 100644
--- a/arch/parisc/Kconfig
+++ b/arch/parisc/Kconfig
@@ -10,6 +10,7 @@ config PARISC
select ARCH_HAS_ELF_RANDOMIZE
select ARCH_HAS_STRICT_KERNEL_RWX
select ARCH_HAS_UBSAN_SANITIZE_ALL
+ select ARCH_HAS_VM_GET_PAGE_PROT
select ARCH_NO_SG_CHAIN
select ARCH_SUPPORTS_HUGETLBFS if PA20
select ARCH_SUPPORTS_MEMORY_FAILURE
diff --git a/arch/parisc/include/asm/pgtable.h b/arch/parisc/include/asm/pgtable.h
index 3e7cf882639f..80d99b2b5913 100644
--- a/arch/parisc/include/asm/pgtable.h
+++ b/arch/parisc/include/asm/pgtable.h
@@ -269,26 +269,6 @@ extern void __update_cache(pte_t pte);
* pages.
*/

- /*xwr*/
-#define __P000 PAGE_NONE
-#define __P001 PAGE_READONLY
-#define __P010 __P000 /* copy on write */
-#define __P011 __P001 /* copy on write */
-#define __P100 PAGE_EXECREAD
-#define __P101 PAGE_EXECREAD
-#define __P110 __P100 /* copy on write */
-#define __P111 __P101 /* copy on write */
-
-#define __S000 PAGE_NONE
-#define __S001 PAGE_READONLY
-#define __S010 PAGE_WRITEONLY
-#define __S011 PAGE_SHARED
-#define __S100 PAGE_EXECREAD
-#define __S101 PAGE_EXECREAD
-#define __S110 PAGE_RWX
-#define __S111 PAGE_RWX
-
-
extern pgd_t swapper_pg_dir[]; /* declared in init_task.c */

/* initial page tables for 0-8MB for kernel */
diff --git a/arch/parisc/mm/init.c b/arch/parisc/mm/init.c
index 1dc2e88e7b04..f9e841f874a8 100644
--- a/arch/parisc/mm/init.c
+++ b/arch/parisc/mm/init.c
@@ -865,3 +865,43 @@ void flush_tlb_all(void)
spin_unlock(&sid_lock);
}
#endif
+
+pgprot_t vm_get_page_prot(unsigned long vm_flags)
+{
+ switch (vm_flags & (VM_READ | VM_WRITE | VM_EXEC | VM_SHARED)) {
+ case VM_NONE:
+ return PAGE_NONE;
+ case VM_READ:
+ return PAGE_READONLY;
+ /* copy on write */
+ case VM_WRITE:
+ return PAGE_NONE;
+ /* copy on write */
+ case VM_WRITE | VM_READ:
+ return PAGE_READONLY;
+ case VM_EXEC:
+ case VM_EXEC | VM_READ:
+ /* copy on write */
+ case VM_EXEC | VM_WRITE:
+ /* copy on write */
+ case VM_EXEC | VM_WRITE | VM_READ:
+ return PAGE_EXECREAD;
+ case VM_SHARED:
+ return PAGE_NONE;
+ case VM_SHARED | VM_READ:
+ return PAGE_READONLY;
+ case VM_SHARED | VM_WRITE:
+ return PAGE_WRITEONLY;
+ case VM_SHARED | VM_WRITE | VM_READ:
+ return PAGE_SHARED;
+ case VM_SHARED | VM_EXEC:
+ case VM_SHARED | VM_EXEC | VM_READ:
+ return PAGE_EXECREAD;
+ case VM_SHARED | VM_EXEC | VM_WRITE:
+ case VM_SHARED | VM_EXEC | VM_WRITE | VM_READ:
+ return PAGE_RWX;
+ default:
+ BUILD_BUG();
+ }
+}
+EXPORT_SYMBOL(vm_get_page_prot);
--
2.25.1