diff options
Diffstat (limited to 'arch/s390/kernel/vdso64/gettimeofday.S')
| -rw-r--r-- | arch/s390/kernel/vdso64/gettimeofday.S | 71 |
1 files changed, 71 insertions, 0 deletions
diff --git a/arch/s390/kernel/vdso64/gettimeofday.S b/arch/s390/kernel/vdso64/gettimeofday.S new file mode 100644 index 000000000..aebe10dc7 --- /dev/null +++ b/arch/s390/kernel/vdso64/gettimeofday.S @@ -0,0 +1,71 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Userland implementation of gettimeofday() for 64 bits processes in a + * s390 kernel for use in the vDSO + * + * Copyright IBM Corp. 2008 + * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com) + */ +#include <asm/vdso.h> +#include <asm/asm-offsets.h> +#include <asm/unistd.h> +#include <asm/dwarf.h> +#include <asm/ptrace.h> + + .text + .align 4 + .globl __kernel_gettimeofday + .type __kernel_gettimeofday,@function +__kernel_gettimeofday: + CFI_STARTPROC + aghi %r15,-16 + CFI_ADJUST_CFA_OFFSET 16 + CFI_VAL_OFFSET 15, -STACK_FRAME_OVERHEAD + larl %r5,_vdso_data +0: ltgr %r3,%r3 /* check if tz is NULL */ + je 1f + mvc 0(8,%r3),__VDSO_TIMEZONE(%r5) +1: ltgr %r2,%r2 /* check if tv is NULL */ + je 4f + lg %r4,__VDSO_UPD_COUNT(%r5) /* load update counter */ + tmll %r4,0x0001 /* pending update ? loop */ + jnz 0b + stcke 0(%r15) /* Store TOD clock */ + lg %r1,1(%r15) + lg %r0,__VDSO_TS_END(%r5) /* TOD steering end time */ + slgr %r0,%r1 /* now - ts_steering_end */ + ltgr %r0,%r0 /* past end of steering ? */ + jm 6f + srlg %r0,%r0,15 /* 1 per 2^16 */ + tm __VDSO_TS_DIR+3(%r5),0x01 /* steering direction? */ + jz 7f + lcgr %r0,%r0 /* negative TOD offset */ +7: algr %r1,%r0 /* add steering offset */ +6: sg %r1,__VDSO_XTIME_STAMP(%r5) /* TOD - cycle_last */ + msgf %r1,__VDSO_TK_MULT(%r5) /* * tk->mult */ + alg %r1,__VDSO_XTIME_NSEC(%r5) /* + tk->xtime_nsec */ + lg %r0,__VDSO_XTIME_SEC(%r5) /* tk->xtime_sec */ + clg %r4,__VDSO_UPD_COUNT(%r5) /* check update counter */ + jne 0b + lgf %r5,__VDSO_TK_SHIFT(%r5) /* Timekeeper shift */ + srlg %r1,%r1,0(%r5) /* >> tk->shift */ + larl %r5,5f +2: clg %r1,0(%r5) + jl 3f + slg %r1,0(%r5) + aghi %r0,1 + j 2b +3: stg %r0,0(%r2) /* store tv->tv_sec */ + slgr %r0,%r0 /* tv_nsec -> tv_usec */ + ml %r0,8(%r5) + srlg %r0,%r0,6 + stg %r0,8(%r2) /* store tv->tv_usec */ +4: lghi %r2,0 + aghi %r15,16 + CFI_ADJUST_CFA_OFFSET -16 + CFI_RESTORE 15 + br %r14 + CFI_ENDPROC +5: .quad 1000000000 + .long 274877907 + .size __kernel_gettimeofday,.-__kernel_gettimeofday |