36 lines
920 B
C
36 lines
920 B
C
/* SPDX-License-Identifier: GPL-2.0 */
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#ifndef _ASM_X86_VSYSCALL_H
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#define _ASM_X86_VSYSCALL_H
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#include <linux/seqlock.h>
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#include <uapi/asm/vsyscall.h>
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#include <asm/page_types.h>
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#ifdef CONFIG_X86_VSYSCALL_EMULATION
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extern void map_vsyscall(void);
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extern void set_vsyscall_pgtable_user_bits(pgd_t *root);
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/*
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* Called on instruction fetch fault in vsyscall page.
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* Returns true if handled.
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*/
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extern bool emulate_vsyscall(struct pt_regs *regs, unsigned long address);
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#else
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static inline void map_vsyscall(void) {}
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static inline bool emulate_vsyscall(struct pt_regs *regs, unsigned long address)
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{
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return false;
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}
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#endif
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/*
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* The (legacy) vsyscall page is the long page in the kernel portion
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* of the address space that has user-accessible permissions.
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*/
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static inline bool is_vsyscall_vaddr(unsigned long vaddr)
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{
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return unlikely((vaddr & PAGE_MASK) == VSYSCALL_ADDR);
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}
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#endif /* _ASM_X86_VSYSCALL_H */
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