[PATCH v3 04/11] arm64/mm: Add set_memory_device() and set_memory_normal()
From: Thierry Reding <thierry.reding@kernel.org>
Date: 2026-07-01 16:08:55
Also in:
dri-devel, linux-devicetree, linux-iommu, linux-media, linux-mm, linux-s390, linux-tegra, lkml
Subsystem:
arm64 port (aarch64 architecture), the rest · Maintainers:
Catalin Marinas, Will Deacon, Linus Torvalds
From: Chun Ng <redacted> Add helpers to swap PROT_NORMAL and PROT_DEVICE_nGnRnE protection bits on a kernel-linear-map range. Signed-off-by: Chun Ng <redacted> Signed-off-by: Thierry Reding <redacted> --- arch/arm64/include/asm/set_memory.h | 2 ++ arch/arm64/mm/pageattr.c | 16 ++++++++++++++++ include/linux/set_memory.h | 11 +++++++++++ 3 files changed, 29 insertions(+)
diff --git a/arch/arm64/include/asm/set_memory.h b/arch/arm64/include/asm/set_memory.h
index 90f61b17275e..6a7030609789 100644
--- a/arch/arm64/include/asm/set_memory.h
+++ b/arch/arm64/include/asm/set_memory.h@@ -10,6 +10,8 @@ bool can_set_direct_map(void); #define can_set_direct_map can_set_direct_map int set_memory_valid(unsigned long addr, int numpages, int enable); +int set_memory_device(unsigned long addr, int numpages); +int set_memory_normal(unsigned long addr, int numpages); int set_direct_map_invalid_noflush(struct page *page); int set_direct_map_default_noflush(struct page *page);
diff --git a/arch/arm64/mm/pageattr.c b/arch/arm64/mm/pageattr.c
index bbe98ac9ad8c..871b59a6c9ea 100644
--- a/arch/arm64/mm/pageattr.c
+++ b/arch/arm64/mm/pageattr.c@@ -251,6 +251,22 @@ int set_memory_valid(unsigned long addr, int numpages, int enable) __pgprot(PTE_PRESENT_VALID_KERNEL)); } +int set_memory_device(unsigned long addr, int numpages) +{ + return __change_memory_common(addr, PAGE_SIZE * numpages, + __pgprot(PROT_DEVICE_nGnRnE), + __pgprot(PROT_NORMAL)); +} +EXPORT_SYMBOL_GPL(set_memory_device); + +int set_memory_normal(unsigned long addr, int numpages) +{ + return __change_memory_common(addr, PAGE_SIZE * numpages, + __pgprot(PROT_NORMAL), + __pgprot(PROT_DEVICE_nGnRnE)); +} +EXPORT_SYMBOL_GPL(set_memory_normal); + int set_direct_map_invalid_noflush(struct page *page) { pgprot_t clear_mask = __pgprot(PTE_PRESENT_VALID_KERNEL);
diff --git a/include/linux/set_memory.h b/include/linux/set_memory.h
index 3030d9245f5a..abcb11378fdb 100644
--- a/include/linux/set_memory.h
+++ b/include/linux/set_memory.h@@ -72,6 +72,17 @@ static inline int clear_mce_nospec(unsigned long pfn) } #endif +#ifndef CONFIG_ARM64 +static inline int set_memory_device(unsigned long addr, int numpages) +{ + return 0; +} +static inline int set_memory_normal(unsigned long addr, int numpages) +{ + return 0; +} +#endif + #ifndef CONFIG_ARCH_HAS_MEM_ENCRYPT static inline int set_memory_encrypted(unsigned long addr, int numpages) {
--
2.54.0