qemu

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/*
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 * s390x linux replacement vdso.
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 *
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 * Copyright 2023 Linaro, Ltd.
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 *
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 * SPDX-License-Identifier: GPL-2.0-or-later
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 */
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#include <asm/unistd.h>
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#include "vdso-asmoffset.h"
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.macro endf name
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	.globl	\name
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	.type	\name, @function
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	.size	\name, . - \name
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.endm
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.macro raw_syscall n
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        .ifne	\n < 0x100
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	svc	\n
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	.else
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	lghi	%r1, \n
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	svc	0
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        .endif
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.endm
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.macro vdso_syscall name, nr
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\name:
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	.cfi_startproc
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	aghi	%r15, -(STACK_FRAME_OVERHEAD + 16)
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	.cfi_adjust_cfa_offset STACK_FRAME_OVERHEAD + 16
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	stg	%r14, STACK_FRAME_OVERHEAD(%r15)
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	.cfi_rel_offset %r14, STACK_FRAME_OVERHEAD
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	raw_syscall \nr
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	lg	%r14, STACK_FRAME_OVERHEAD(%r15)
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	aghi	%r15, STACK_FRAME_OVERHEAD + 16
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	.cfi_restore %r14
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	.cfi_adjust_cfa_offset -(STACK_FRAME_OVERHEAD + 16)
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	br	%r14
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	.cfi_endproc
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endf	\name
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.endm
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vdso_syscall __kernel_gettimeofday, __NR_gettimeofday
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vdso_syscall __kernel_clock_gettime, __NR_clock_gettime
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vdso_syscall __kernel_clock_getres, __NR_clock_getres
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vdso_syscall __kernel_getcpu, __NR_getcpu
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/*
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 * TODO unwind info, though we're ok without it.
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 * The kernel supplies bogus empty unwind info, and it is likely ignored
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 * by all users.  Without it we get the fallback signal frame handling.
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 */
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__kernel_sigreturn:
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	raw_syscall __NR_sigreturn
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endf	__kernel_sigreturn
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__kernel_rt_sigreturn:
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	raw_syscall __NR_rt_sigreturn
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endf	__kernel_rt_sigreturn
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