From: Hou Tao <houtao1@xxxxxxxxxx> [ Upstream commit ee0e39a63b78849f8abbef268b13e4838569f646 ] Move is_vsyscall_vaddr() into asm/vsyscall.h to make it available for copy_from_kernel_nofault_allowed() in arch/x86/mm/maccess.c. Reviewed-by: Sohil Mehta <sohil.mehta@xxxxxxxxx> Signed-off-by: Hou Tao <houtao1@xxxxxxxxxx> Link: https://lore.kernel.org/r/20240202103935.3154011-2-houtao@xxxxxxxxxxxxxxx Signed-off-by: Alexei Starovoitov <ast@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- arch/x86/include/asm/vsyscall.h | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/arch/x86/include/asm/vsyscall.h b/arch/x86/include/asm/vsyscall.h index b986b2ca688a0..8154b25cb975a 100644 --- a/arch/x86/include/asm/vsyscall.h +++ b/arch/x86/include/asm/vsyscall.h @@ -4,6 +4,7 @@ #include <linux/seqlock.h> #include <uapi/asm/vsyscall.h> +#include <asm/page_types.h> #ifdef CONFIG_X86_VSYSCALL_EMULATION extern void map_vsyscall(void); @@ -22,4 +23,13 @@ static inline bool emulate_vsyscall(struct pt_regs *regs, unsigned long address) } #endif +/* + * The (legacy) vsyscall page is the long page in the kernel portion + * of the address space that has user-accessible permissions. + */ +static inline bool is_vsyscall_vaddr(unsigned long vaddr) +{ + return unlikely((vaddr & PAGE_MASK) == VSYSCALL_ADDR); +} + #endif /* _ASM_X86_VSYSCALL_H */ -- 2.43.0
