[RFC 2/5] mm/powerpc: Make VDSO unmap generic
From: Christopher Covington <hidden>
Date: 2016-04-28 15:21:39
Also in:
linux-arch, linux-arm-kernel, linux-mm, lkml
Subsystem:
generic include/asm header files, linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Arnd Bergmann, Madhavan Srinivasan, Michael Ellerman, Linus Torvalds
In order to support unmapping the VDSO on additional architectures, move the unmap code out from arch/powerpc. Architectures that wish to use the generic logic must have an unsigned long vdso in mm->context and can opt in by selecting CONFIG_ARCH_WANT_VDSO_MAP. This allows PowerPC to go back to using the generic MM hooks, instead of carrying its own. Signed-off-by: Christopher Covington <redacted> --- arch/powerpc/Kconfig | 1 + arch/powerpc/include/asm/mmu_context.h | 35 +--------------------------------- include/asm-generic/mm_hooks.h | 4 ++++ 3 files changed, 6 insertions(+), 34 deletions(-)
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 7cd32c0..f74320e 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig@@ -160,6 +160,7 @@ config PPC select HAVE_ARCH_SECCOMP_FILTER select ARCH_HAS_UBSAN_SANITIZE_ALL select ARCH_SUPPORTS_DEFERRED_STRUCT_PAGE_INIT + select ARCH_WANT_VDSO_MAP config GENERIC_CSUM def_bool CPU_LITTLE_ENDIAN
diff --git a/arch/powerpc/include/asm/mmu_context.h b/arch/powerpc/include/asm/mmu_context.h
index 508b842..3e51842 100644
--- a/arch/powerpc/include/asm/mmu_context.h
+++ b/arch/powerpc/include/asm/mmu_context.h@@ -8,6 +8,7 @@ #include <linux/spinlock.h> #include <asm/mmu.h> #include <asm/cputable.h> +#include <asm-generic/mm_hooks.h> #include <asm/cputhreads.h> /*
@@ -126,39 +127,5 @@ static inline void enter_lazy_tlb(struct mm_struct *mm, #endif } -static inline void arch_dup_mmap(struct mm_struct *oldmm, - struct mm_struct *mm) -{ -} - -static inline void arch_exit_mmap(struct mm_struct *mm) -{ -} - -static inline void arch_unmap(struct mm_struct *mm, - struct vm_area_struct *vma, - unsigned long start, unsigned long end) -{ - if (start <= mm->context.vdso && mm->context.vdso < end) - mm->context.vdso = 0; -} - -static inline void arch_bprm_mm_init(struct mm_struct *mm, - struct vm_area_struct *vma) -{ -} - -static inline bool arch_vma_access_permitted(struct vm_area_struct *vma, - bool write, bool execute, bool foreign) -{ - /* by default, allow everything */ - return true; -} - -static inline bool arch_pte_access_permitted(pte_t pte, bool write) -{ - /* by default, allow everything */ - return true; -} #endif /* __KERNEL__ */ #endif /* __ASM_POWERPC_MMU_CONTEXT_H */
diff --git a/include/asm-generic/mm_hooks.h b/include/asm-generic/mm_hooks.h
index cc5d9a14..6645116 100644
--- a/include/asm-generic/mm_hooks.h
+++ b/include/asm-generic/mm_hooks.h@@ -19,6 +19,10 @@ static inline void arch_unmap(struct mm_struct *mm, struct vm_area_struct *vma, unsigned long start, unsigned long end) { +#ifdef CONFIG_ARCH_WANT_VDSO_MAP + if (start <= mm->context.vdso && mm->context.vdso < end) + mm->context.vdso = 0; +#endif /* CONFIG_ARCH_WANT_VDSO_MAP */ } static inline void arch_bprm_mm_init(struct mm_struct *mm,
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