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	 6d47c23b16
			
		
	
	
		6d47c23b16
		
	
	
	
	
		
			
			On arm64, set_direct_map_*() functions may return 0 without actually changing the linear map. This behaviour can be controlled using kernel parameters, so we need a way to determine at runtime whether calls to set_direct_map_invalid_noflush() and set_direct_map_default_noflush() have any effect. Extend set_memory API with can_set_direct_map() function that allows checking if calling set_direct_map_*() will actually change the page table, replace several occurrences of open coded checks in arm64 with the new function and provide a generic stub for architectures that always modify page tables upon calls to set_direct_map APIs. [arnd@arndb.de: arm64: kfence: fix header inclusion ] Link: https://lkml.kernel.org/r/20210518072034.31572-4-rppt@kernel.org Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: David Hildenbrand <david@redhat.com> Acked-by: James Bottomley <James.Bottomley@HansenPartnership.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Christopher Lameter <cl@linux.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Elena Reshetova <elena.reshetova@intel.com> Cc: Hagen Paul Pfeifer <hagen@jauu.net> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Bottomley <jejb@linux.ibm.com> Cc: "Kirill A. Shutemov" <kirill@shutemov.name> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Michael Kerrisk <mtk.manpages@gmail.com> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Palmer Dabbelt <palmerdabbelt@google.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rick Edgecombe <rick.p.edgecombe@intel.com> Cc: Roman Gushchin <guro@fb.com> Cc: Shakeel Butt <shakeelb@google.com> Cc: Shuah Khan <shuah@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tycho Andersen <tycho@tycho.ws> Cc: Will Deacon <will@kernel.org> Cc: kernel test robot <lkp@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
		
			
				
	
	
		
			71 lines
		
	
	
	
		
			1.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			71 lines
		
	
	
	
		
			1.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* SPDX-License-Identifier: GPL-2.0-only */
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| /*
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|  * Copyright 2017, Michael Ellerman, IBM Corporation.
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|  */
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| #ifndef _LINUX_SET_MEMORY_H_
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| #define _LINUX_SET_MEMORY_H_
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| 
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| #ifdef CONFIG_ARCH_HAS_SET_MEMORY
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| #include <asm/set_memory.h>
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| #else
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| static inline int set_memory_ro(unsigned long addr, int numpages) { return 0; }
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| static inline int set_memory_rw(unsigned long addr, int numpages) { return 0; }
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| static inline int set_memory_x(unsigned long addr,  int numpages) { return 0; }
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| static inline int set_memory_nx(unsigned long addr, int numpages) { return 0; }
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| #endif
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| 
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| #ifndef CONFIG_ARCH_HAS_SET_DIRECT_MAP
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| static inline int set_direct_map_invalid_noflush(struct page *page)
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| {
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| 	return 0;
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| }
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| static inline int set_direct_map_default_noflush(struct page *page)
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| {
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| 	return 0;
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| }
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| 
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| static inline bool kernel_page_present(struct page *page)
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| {
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| 	return true;
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| }
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| #else /* CONFIG_ARCH_HAS_SET_DIRECT_MAP */
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| /*
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|  * Some architectures, e.g. ARM64 can disable direct map modifications at
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|  * boot time. Let them overrive this query.
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|  */
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| #ifndef can_set_direct_map
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| static inline bool can_set_direct_map(void)
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| {
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| 	return true;
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| }
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| #define can_set_direct_map can_set_direct_map
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| #endif
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| #endif /* CONFIG_ARCH_HAS_SET_DIRECT_MAP */
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| 
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| #ifndef set_mce_nospec
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| static inline int set_mce_nospec(unsigned long pfn, bool unmap)
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| {
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| 	return 0;
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| }
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| #endif
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| 
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| #ifndef clear_mce_nospec
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| static inline int clear_mce_nospec(unsigned long pfn)
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| {
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| 	return 0;
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| }
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| #endif
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| 
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| #ifndef CONFIG_ARCH_HAS_MEM_ENCRYPT
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| static inline int set_memory_encrypted(unsigned long addr, int numpages)
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| {
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| 	return 0;
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| }
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| 
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| static inline int set_memory_decrypted(unsigned long addr, int numpages)
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| {
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| 	return 0;
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| }
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| #endif /* CONFIG_ARCH_HAS_MEM_ENCRYPT */
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| 
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| #endif /* _LINUX_SET_MEMORY_H_ */
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