[PATCH v2 25/37] powerpc: Refactor permission masks used for __P/__S table and kernel memory flags
From: Christophe Leroy <hidden>
Date: 2023-09-25 18:35:26
Also in:
lkml
Subsystem:
linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Madhavan Srinivasan, Michael Ellerman, Linus Torvalds
Prepare a common version of the permission masks that will be based on _PAGE_NA, _PAGE_RO, _PAGE_ROX, _PAGE_RW, _PAGE_RWX that will be defined in platform specific headers in later patches. Put them in a new header pgtable-masks.h which will be included by platforms. And prepare a common version of flags used for mapping kernel memory that will be based on _PAGE_RO, _PAGE_ROX, _PAGE_RW, _PAGE_RWX that will be defined in platform specific headers. Put them in unless _PAGE_KERNEL_RO is already defined so that platform specific definitions can be dismantled one by one. Signed-off-by: Christophe Leroy <redacted> --- arch/powerpc/include/asm/pgtable-masks.h | 30 ++++++++++++++++++++++++ 1 file changed, 30 insertions(+) create mode 100644 arch/powerpc/include/asm/pgtable-masks.h
diff --git a/arch/powerpc/include/asm/pgtable-masks.h b/arch/powerpc/include/asm/pgtable-masks.h
new file mode 100644
index 000000000000..808a3b9e8fc0
--- /dev/null
+++ b/arch/powerpc/include/asm/pgtable-masks.h@@ -0,0 +1,30 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _ASM_POWERPC_PGTABLE_MASKS_H +#define _ASM_POWERPC_PGTABLE_MASKS_H + +#ifndef _PAGE_NA +#define _PAGE_NA 0 +#define _PAGE_RO _PAGE_READ +#define _PAGE_ROX (_PAGE_READ | _PAGE_EXEC) +#define _PAGE_RW (_PAGE_READ | _PAGE_WRITE) +#define _PAGE_RWX (_PAGE_READ | _PAGE_WRITE | _PAGE_EXEC) +#endif + +/* Permission flags for kernel mappings */ +#ifndef _PAGE_KERNEL_RO +#define _PAGE_KERNEL_RO _PAGE_RO +#define _PAGE_KERNEL_ROX _PAGE_ROX +#define _PAGE_KERNEL_RW (_PAGE_RW | _PAGE_DIRTY) +#define _PAGE_KERNEL_RWX (_PAGE_RWX | _PAGE_DIRTY) +#endif + +/* Permission masks used to generate the __P and __S table */ +#define PAGE_NONE __pgprot(_PAGE_BASE | _PAGE_NA) +#define PAGE_SHARED __pgprot(_PAGE_BASE | _PAGE_RW) +#define PAGE_SHARED_X __pgprot(_PAGE_BASE | _PAGE_RWX) +#define PAGE_COPY __pgprot(_PAGE_BASE | _PAGE_RO) +#define PAGE_COPY_X __pgprot(_PAGE_BASE | _PAGE_ROX) +#define PAGE_READONLY __pgprot(_PAGE_BASE | _PAGE_RO) +#define PAGE_READONLY_X __pgprot(_PAGE_BASE | _PAGE_ROX) + +#endif /* _ASM_POWERPC_PGTABLE_MASKS_H */
--
2.41.0