From 9b0aa14e31555b64460c1ee323d0e19bf891958b Mon Sep 17 00:00:00 2001 From: AKASHI Takahiro Date: Mon, 3 Apr 2017 11:24:33 +0900 Subject: [PATCH] arm64: mm: add set_memory_valid() This function validates and invalidates PTE entries, and will be utilized in kdump to protect loaded crash dump kernel image. Signed-off-by: AKASHI Takahiro Reviewed-by: Ard Biesheuvel Signed-off-by: Catalin Marinas --- arch/arm64/include/asm/cacheflush.h | 1 + arch/arm64/mm/pageattr.c | 15 +++++++++------ 2 files changed, 10 insertions(+), 6 deletions(-) diff --git a/arch/arm64/include/asm/cacheflush.h b/arch/arm64/include/asm/cacheflush.h index 5a2a6ee..728f933 100644 --- a/arch/arm64/include/asm/cacheflush.h +++ b/arch/arm64/include/asm/cacheflush.h @@ -154,5 +154,6 @@ int set_memory_ro(unsigned long addr, int numpages); int set_memory_rw(unsigned long addr, int numpages); int set_memory_x(unsigned long addr, int numpages); int set_memory_nx(unsigned long addr, int numpages); +int set_memory_valid(unsigned long addr, unsigned long size, int enable); #endif diff --git a/arch/arm64/mm/pageattr.c b/arch/arm64/mm/pageattr.c index 8def55e..3212ee0 100644 --- a/arch/arm64/mm/pageattr.c +++ b/arch/arm64/mm/pageattr.c @@ -125,20 +125,23 @@ int set_memory_x(unsigned long addr, int numpages) } EXPORT_SYMBOL_GPL(set_memory_x); -#ifdef CONFIG_DEBUG_PAGEALLOC -void __kernel_map_pages(struct page *page, int numpages, int enable) +int set_memory_valid(unsigned long addr, int numpages, int enable) { - unsigned long addr = (unsigned long) page_address(page); - if (enable) - __change_memory_common(addr, PAGE_SIZE * numpages, + return __change_memory_common(addr, PAGE_SIZE * numpages, __pgprot(PTE_VALID), __pgprot(0)); else - __change_memory_common(addr, PAGE_SIZE * numpages, + return __change_memory_common(addr, PAGE_SIZE * numpages, __pgprot(0), __pgprot(PTE_VALID)); } + +#ifdef CONFIG_DEBUG_PAGEALLOC +void __kernel_map_pages(struct page *page, int numpages, int enable) +{ + set_memory_valid((unsigned long)page_address(page), numpages, enable); +} #ifdef CONFIG_HIBERNATION /* * When built with CONFIG_DEBUG_PAGEALLOC and CONFIG_HIBERNATION, this function -- 2.7.4