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/* SPDX-License-Identifier: GPL-2.0 */
#include <asm/vdso.h>
#include <asm/unistd.h>
#include <asm/asm-offsets.h>
#include <asm/dwarf.h>
#include <asm/ptrace.h>
#define WRAPPER_FRAME_SIZE (STACK_FRAME_OVERHEAD+8)
/*
* Older glibc version called vdso without allocating a stackframe. This wrapper
* is just used to allocate a stackframe. See
* https://sourceware.org/git/?p=glibc.git;a=commit;h=478593e6374f3818da39332260dc453cb19cfa1e
* for details.
*/
.macro vdso_func func
.globl __kernel_\func
.type __kernel_\func,@function
.align 8
__kernel_\func:
CFI_STARTPROC
aghi %r15,-WRAPPER_FRAME_SIZE
CFI_DEF_CFA_OFFSET (STACK_FRAME_OVERHEAD + WRAPPER_FRAME_SIZE)
CFI_VAL_OFFSET 15, -STACK_FRAME_OVERHEAD
stg %r14,STACK_FRAME_OVERHEAD(%r15)
brasl %r14,__s390_vdso_\func
lg %r14,STACK_FRAME_OVERHEAD(%r15)
aghi %r15,WRAPPER_FRAME_SIZE
CFI_DEF_CFA_OFFSET STACK_FRAME_OVERHEAD
CFI_RESTORE 15
br %r14
CFI_ENDPROC
.size __kernel_\func,.-__kernel_\func
.endm
vdso_func gettimeofday
vdso_func clock_getres
vdso_func clock_gettime
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