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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
commit76cb841cb886eef6b3bee341a2266c76578724ad (patch)
treef5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /arch/s390/kernel/vdso32/gettimeofday.S
parentInitial commit. (diff)
downloadlinux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz
linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip
Adding upstream version 4.19.249.upstream/4.19.249upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r--arch/s390/kernel/vdso32/gettimeofday.S103
1 files changed, 103 insertions, 0 deletions
diff --git a/arch/s390/kernel/vdso32/gettimeofday.S b/arch/s390/kernel/vdso32/gettimeofday.S
new file mode 100644
index 000000000..b23063fbc
--- /dev/null
+++ b/arch/s390/kernel/vdso32/gettimeofday.S
@@ -0,0 +1,103 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Userland implementation of gettimeofday() for 32 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
+ ahi %r15,-16
+ CFI_ADJUST_CFA_OFFSET 16
+ CFI_VAL_OFFSET 15, -STACK_FRAME_OVERHEAD
+ basr %r5,0
+0: al %r5,13f-0b(%r5) /* get &_vdso_data */
+1: ltr %r3,%r3 /* check if tz is NULL */
+ je 2f
+ mvc 0(8,%r3),__VDSO_TIMEZONE(%r5)
+2: ltr %r2,%r2 /* check if tv is NULL */
+ je 10f
+ l %r4,__VDSO_UPD_COUNT+4(%r5) /* load update counter */
+ tml %r4,0x0001 /* pending update ? loop */
+ jnz 1b
+ stcke 0(%r15) /* Store TOD clock */
+ lm %r0,%r1,__VDSO_TS_END(%r5) /* TOD steering end time */
+ s %r0,1(%r15)
+ sl %r1,5(%r15)
+ brc 3,14f
+ ahi %r0,-1
+14: ltr %r0,%r0 /* past end of steering? */
+ jm 16f
+ srdl %r0,15 /* 1 per 2^16 */
+ tm __VDSO_TS_DIR+3(%r5),0x01 /* steering direction? */
+ jz 15f
+ lcr %r0,%r0 /* negative TOD offset */
+ lcr %r1,%r1
+ je 15f
+ ahi %r0,-1
+15: a %r0,1(%r15) /* add TOD timestamp */
+ al %r1,5(%r15)
+ brc 12,17f
+ ahi %r0,1
+ j 17f
+16: lm %r0,%r1,1(%r15) /* load TOD timestamp */
+17: s %r0,__VDSO_XTIME_STAMP(%r5) /* TOD - cycle_last */
+ sl %r1,__VDSO_XTIME_STAMP+4(%r5)
+ brc 3,3f
+ ahi %r0,-1
+3: ms %r0,__VDSO_TK_MULT(%r5) /* * tk->mult */
+ st %r0,0(%r15)
+ l %r0,__VDSO_TK_MULT(%r5)
+ ltr %r1,%r1
+ mr %r0,%r0
+ jnm 4f
+ a %r0,__VDSO_TK_MULT(%r5)
+4: al %r0,0(%r15)
+ al %r0,__VDSO_XTIME_NSEC(%r5) /* + xtime */
+ al %r1,__VDSO_XTIME_NSEC+4(%r5)
+ brc 12,5f
+ ahi %r0,1
+5: mvc 0(4,%r15),__VDSO_XTIME_SEC+4(%r5)
+ cl %r4,__VDSO_UPD_COUNT+4(%r5) /* check update counter */
+ jne 1b
+ l %r4,__VDSO_TK_SHIFT(%r5) /* Timekeeper shift */
+ srdl %r0,0(%r4) /* >> tk->shift */
+ l %r4,0(%r15) /* get tv_sec from stack */
+ basr %r5,0
+6: ltr %r0,%r0
+ jnz 7f
+ cl %r1,11f-6b(%r5)
+ jl 8f
+7: ahi %r4,1
+ sl %r1,11f-6b(%r5)
+ brc 3,6b
+ ahi %r0,-1
+ j 6b
+8: st %r4,0(%r2) /* store tv->tv_sec */
+ ltr %r1,%r1
+ m %r0,12f-6b(%r5)
+ jnm 9f
+ al %r0,12f-6b(%r5)
+9: srl %r0,6
+ st %r0,4(%r2) /* store tv->tv_usec */
+10: slr %r2,%r2
+ ahi %r15,16
+ CFI_ADJUST_CFA_OFFSET -16
+ CFI_RESTORE 15
+ br %r14
+ CFI_ENDPROC
+11: .long 1000000000
+12: .long 274877907
+13: .long _vdso_data - 0b
+ .size __kernel_gettimeofday,.-__kernel_gettimeofday