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-rw-r--r--include/vdso/bits.h10
-rw-r--r--include/vdso/clocksource.h22
-rw-r--r--include/vdso/const.h10
-rw-r--r--include/vdso/datapage.h142
-rw-r--r--include/vdso/helpers.h56
-rw-r--r--include/vdso/jiffies.h11
-rw-r--r--include/vdso/ktime.h16
-rw-r--r--include/vdso/limits.h19
-rw-r--r--include/vdso/math64.h24
-rw-r--r--include/vdso/processor.h14
-rw-r--r--include/vdso/time.h12
-rw-r--r--include/vdso/time32.h17
-rw-r--r--include/vdso/time64.h15
-rw-r--r--include/vdso/vsyscall.h14
14 files changed, 382 insertions, 0 deletions
diff --git a/include/vdso/bits.h b/include/vdso/bits.h
new file mode 100644
index 0000000000..388b212088
--- /dev/null
+++ b/include/vdso/bits.h
@@ -0,0 +1,10 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __VDSO_BITS_H
+#define __VDSO_BITS_H
+
+#include <vdso/const.h>
+
+#define BIT(nr) (UL(1) << (nr))
+#define BIT_ULL(nr) (ULL(1) << (nr))
+
+#endif /* __VDSO_BITS_H */
diff --git a/include/vdso/clocksource.h b/include/vdso/clocksource.h
new file mode 100644
index 0000000000..c682e7c602
--- /dev/null
+++ b/include/vdso/clocksource.h
@@ -0,0 +1,22 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __VDSO_CLOCKSOURCE_H
+#define __VDSO_CLOCKSOURCE_H
+
+#include <vdso/limits.h>
+
+#ifdef CONFIG_GENERIC_GETTIMEOFDAY
+#include <asm/vdso/clocksource.h>
+#endif /* CONFIG_GENERIC_GETTIMEOFDAY */
+
+enum vdso_clock_mode {
+ VDSO_CLOCKMODE_NONE,
+#ifdef CONFIG_GENERIC_GETTIMEOFDAY
+ VDSO_ARCH_CLOCKMODES,
+#endif
+ VDSO_CLOCKMODE_MAX,
+
+ /* Indicator for time namespace VDSO */
+ VDSO_CLOCKMODE_TIMENS = INT_MAX
+};
+
+#endif /* __VDSO_CLOCKSOURCE_H */
diff --git a/include/vdso/const.h b/include/vdso/const.h
new file mode 100644
index 0000000000..94b385ad43
--- /dev/null
+++ b/include/vdso/const.h
@@ -0,0 +1,10 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __VDSO_CONST_H
+#define __VDSO_CONST_H
+
+#include <uapi/linux/const.h>
+
+#define UL(x) (_UL(x))
+#define ULL(x) (_ULL(x))
+
+#endif /* __VDSO_CONST_H */
diff --git a/include/vdso/datapage.h b/include/vdso/datapage.h
new file mode 100644
index 0000000000..73eb622e76
--- /dev/null
+++ b/include/vdso/datapage.h
@@ -0,0 +1,142 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __VDSO_DATAPAGE_H
+#define __VDSO_DATAPAGE_H
+
+#ifndef __ASSEMBLY__
+
+#include <linux/compiler.h>
+#include <uapi/linux/time.h>
+#include <uapi/linux/types.h>
+#include <uapi/asm-generic/errno-base.h>
+
+#include <vdso/bits.h>
+#include <vdso/clocksource.h>
+#include <vdso/ktime.h>
+#include <vdso/limits.h>
+#include <vdso/math64.h>
+#include <vdso/processor.h>
+#include <vdso/time.h>
+#include <vdso/time32.h>
+#include <vdso/time64.h>
+
+#ifdef CONFIG_ARCH_HAS_VDSO_DATA
+#include <asm/vdso/data.h>
+#else
+struct arch_vdso_data {};
+#endif
+
+#define VDSO_BASES (CLOCK_TAI + 1)
+#define VDSO_HRES (BIT(CLOCK_REALTIME) | \
+ BIT(CLOCK_MONOTONIC) | \
+ BIT(CLOCK_BOOTTIME) | \
+ BIT(CLOCK_TAI))
+#define VDSO_COARSE (BIT(CLOCK_REALTIME_COARSE) | \
+ BIT(CLOCK_MONOTONIC_COARSE))
+#define VDSO_RAW (BIT(CLOCK_MONOTONIC_RAW))
+
+#define CS_HRES_COARSE 0
+#define CS_RAW 1
+#define CS_BASES (CS_RAW + 1)
+
+/**
+ * struct vdso_timestamp - basetime per clock_id
+ * @sec: seconds
+ * @nsec: nanoseconds
+ *
+ * There is one vdso_timestamp object in vvar for each vDSO-accelerated
+ * clock_id. For high-resolution clocks, this encodes the time
+ * corresponding to vdso_data.cycle_last. For coarse clocks this encodes
+ * the actual time.
+ *
+ * To be noticed that for highres clocks nsec is left-shifted by
+ * vdso_data.cs[x].shift.
+ */
+struct vdso_timestamp {
+ u64 sec;
+ u64 nsec;
+};
+
+/**
+ * struct vdso_data - vdso datapage representation
+ * @seq: timebase sequence counter
+ * @clock_mode: clock mode
+ * @cycle_last: timebase at clocksource init
+ * @mask: clocksource mask
+ * @mult: clocksource multiplier
+ * @shift: clocksource shift
+ * @basetime[clock_id]: basetime per clock_id
+ * @offset[clock_id]: time namespace offset per clock_id
+ * @tz_minuteswest: minutes west of Greenwich
+ * @tz_dsttime: type of DST correction
+ * @hrtimer_res: hrtimer resolution
+ * @__unused: unused
+ * @arch_data: architecture specific data (optional, defaults
+ * to an empty struct)
+ *
+ * vdso_data will be accessed by 64 bit and compat code at the same time
+ * so we should be careful before modifying this structure.
+ *
+ * @basetime is used to store the base time for the system wide time getter
+ * VVAR page.
+ *
+ * @offset is used by the special time namespace VVAR pages which are
+ * installed instead of the real VVAR page. These namespace pages must set
+ * @seq to 1 and @clock_mode to VDSO_CLOCKMODE_TIMENS to force the code into
+ * the time namespace slow path. The namespace aware functions retrieve the
+ * real system wide VVAR page, read host time and add the per clock offset.
+ * For clocks which are not affected by time namespace adjustment the
+ * offset must be zero.
+ */
+struct vdso_data {
+ u32 seq;
+
+ s32 clock_mode;
+ u64 cycle_last;
+ u64 mask;
+ u32 mult;
+ u32 shift;
+
+ union {
+ struct vdso_timestamp basetime[VDSO_BASES];
+ struct timens_offset offset[VDSO_BASES];
+ };
+
+ s32 tz_minuteswest;
+ s32 tz_dsttime;
+ u32 hrtimer_res;
+ u32 __unused;
+
+ struct arch_vdso_data arch_data;
+};
+
+/*
+ * We use the hidden visibility to prevent the compiler from generating a GOT
+ * relocation. Not only is going through a GOT useless (the entry couldn't and
+ * must not be overridden by another library), it does not even work: the linker
+ * cannot generate an absolute address to the data page.
+ *
+ * With the hidden visibility, the compiler simply generates a PC-relative
+ * relocation, and this is what we need.
+ */
+extern struct vdso_data _vdso_data[CS_BASES] __attribute__((visibility("hidden")));
+extern struct vdso_data _timens_data[CS_BASES] __attribute__((visibility("hidden")));
+
+/*
+ * The generic vDSO implementation requires that gettimeofday.h
+ * provides:
+ * - __arch_get_vdso_data(): to get the vdso datapage.
+ * - __arch_get_hw_counter(): to get the hw counter based on the
+ * clock_mode.
+ * - gettimeofday_fallback(): fallback for gettimeofday.
+ * - clock_gettime_fallback(): fallback for clock_gettime.
+ * - clock_getres_fallback(): fallback for clock_getres.
+ */
+#ifdef ENABLE_COMPAT_VDSO
+#include <asm/vdso/compat_gettimeofday.h>
+#else
+#include <asm/vdso/gettimeofday.h>
+#endif /* ENABLE_COMPAT_VDSO */
+
+#endif /* !__ASSEMBLY__ */
+
+#endif /* __VDSO_DATAPAGE_H */
diff --git a/include/vdso/helpers.h b/include/vdso/helpers.h
new file mode 100644
index 0000000000..9a2af9fca4
--- /dev/null
+++ b/include/vdso/helpers.h
@@ -0,0 +1,56 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __VDSO_HELPERS_H
+#define __VDSO_HELPERS_H
+
+#ifndef __ASSEMBLY__
+
+#include <vdso/datapage.h>
+
+static __always_inline u32 vdso_read_begin(const struct vdso_data *vd)
+{
+ u32 seq;
+
+ while (unlikely((seq = READ_ONCE(vd->seq)) & 1))
+ cpu_relax();
+
+ smp_rmb();
+ return seq;
+}
+
+static __always_inline u32 vdso_read_retry(const struct vdso_data *vd,
+ u32 start)
+{
+ u32 seq;
+
+ smp_rmb();
+ seq = READ_ONCE(vd->seq);
+ return seq != start;
+}
+
+static __always_inline void vdso_write_begin(struct vdso_data *vd)
+{
+ /*
+ * WRITE_ONCE it is required otherwise the compiler can validly tear
+ * updates to vd[x].seq and it is possible that the value seen by the
+ * reader it is inconsistent.
+ */
+ WRITE_ONCE(vd[CS_HRES_COARSE].seq, vd[CS_HRES_COARSE].seq + 1);
+ WRITE_ONCE(vd[CS_RAW].seq, vd[CS_RAW].seq + 1);
+ smp_wmb();
+}
+
+static __always_inline void vdso_write_end(struct vdso_data *vd)
+{
+ smp_wmb();
+ /*
+ * WRITE_ONCE it is required otherwise the compiler can validly tear
+ * updates to vd[x].seq and it is possible that the value seen by the
+ * reader it is inconsistent.
+ */
+ WRITE_ONCE(vd[CS_HRES_COARSE].seq, vd[CS_HRES_COARSE].seq + 1);
+ WRITE_ONCE(vd[CS_RAW].seq, vd[CS_RAW].seq + 1);
+}
+
+#endif /* !__ASSEMBLY__ */
+
+#endif /* __VDSO_HELPERS_H */
diff --git a/include/vdso/jiffies.h b/include/vdso/jiffies.h
new file mode 100644
index 0000000000..2f9d596c8b
--- /dev/null
+++ b/include/vdso/jiffies.h
@@ -0,0 +1,11 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __VDSO_JIFFIES_H
+#define __VDSO_JIFFIES_H
+
+#include <asm/param.h> /* for HZ */
+#include <vdso/time64.h>
+
+/* TICK_NSEC is the time between ticks in nsec assuming SHIFTED_HZ */
+#define TICK_NSEC ((NSEC_PER_SEC+HZ/2)/HZ)
+
+#endif /* __VDSO_JIFFIES_H */
diff --git a/include/vdso/ktime.h b/include/vdso/ktime.h
new file mode 100644
index 0000000000..a0fd07239e
--- /dev/null
+++ b/include/vdso/ktime.h
@@ -0,0 +1,16 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __VDSO_KTIME_H
+#define __VDSO_KTIME_H
+
+#include <vdso/jiffies.h>
+
+/*
+ * The resolution of the clocks. The resolution value is returned in
+ * the clock_getres() system call to give application programmers an
+ * idea of the (in)accuracy of timers. Timer values are rounded up to
+ * this resolution values.
+ */
+#define LOW_RES_NSEC TICK_NSEC
+#define KTIME_LOW_RES (LOW_RES_NSEC)
+
+#endif /* __VDSO_KTIME_H */
diff --git a/include/vdso/limits.h b/include/vdso/limits.h
new file mode 100644
index 0000000000..0197888ad0
--- /dev/null
+++ b/include/vdso/limits.h
@@ -0,0 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __VDSO_LIMITS_H
+#define __VDSO_LIMITS_H
+
+#define USHRT_MAX ((unsigned short)~0U)
+#define SHRT_MAX ((short)(USHRT_MAX >> 1))
+#define SHRT_MIN ((short)(-SHRT_MAX - 1))
+#define INT_MAX ((int)(~0U >> 1))
+#define INT_MIN (-INT_MAX - 1)
+#define UINT_MAX (~0U)
+#define LONG_MAX ((long)(~0UL >> 1))
+#define LONG_MIN (-LONG_MAX - 1)
+#define ULONG_MAX (~0UL)
+#define LLONG_MAX ((long long)(~0ULL >> 1))
+#define LLONG_MIN (-LLONG_MAX - 1)
+#define ULLONG_MAX (~0ULL)
+#define UINTPTR_MAX ULONG_MAX
+
+#endif /* __VDSO_LIMITS_H */
diff --git a/include/vdso/math64.h b/include/vdso/math64.h
new file mode 100644
index 0000000000..7da703ee55
--- /dev/null
+++ b/include/vdso/math64.h
@@ -0,0 +1,24 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __VDSO_MATH64_H
+#define __VDSO_MATH64_H
+
+static __always_inline u32
+__iter_div_u64_rem(u64 dividend, u32 divisor, u64 *remainder)
+{
+ u32 ret = 0;
+
+ while (dividend >= divisor) {
+ /* The following asm() prevents the compiler from
+ optimising this loop into a modulo operation. */
+ asm("" : "+rm"(dividend));
+
+ dividend -= divisor;
+ ret++;
+ }
+
+ *remainder = dividend;
+
+ return ret;
+}
+
+#endif /* __VDSO_MATH64_H */
diff --git a/include/vdso/processor.h b/include/vdso/processor.h
new file mode 100644
index 0000000000..fbe8265ea3
--- /dev/null
+++ b/include/vdso/processor.h
@@ -0,0 +1,14 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2020 ARM Ltd.
+ */
+#ifndef __VDSO_PROCESSOR_H
+#define __VDSO_PROCESSOR_H
+
+#ifndef __ASSEMBLY__
+
+#include <asm/vdso/processor.h>
+
+#endif /* __ASSEMBLY__ */
+
+#endif /* __VDSO_PROCESSOR_H */
diff --git a/include/vdso/time.h b/include/vdso/time.h
new file mode 100644
index 0000000000..739f53cd29
--- /dev/null
+++ b/include/vdso/time.h
@@ -0,0 +1,12 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __VDSO_TIME_H
+#define __VDSO_TIME_H
+
+#include <uapi/linux/types.h>
+
+struct timens_offset {
+ s64 sec;
+ u64 nsec;
+};
+
+#endif /* __VDSO_TIME_H */
diff --git a/include/vdso/time32.h b/include/vdso/time32.h
new file mode 100644
index 0000000000..fdf56f932f
--- /dev/null
+++ b/include/vdso/time32.h
@@ -0,0 +1,17 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __VDSO_TIME32_H
+#define __VDSO_TIME32_H
+
+typedef s32 old_time32_t;
+
+struct old_timespec32 {
+ old_time32_t tv_sec;
+ s32 tv_nsec;
+};
+
+struct old_timeval32 {
+ old_time32_t tv_sec;
+ s32 tv_usec;
+};
+
+#endif /* __VDSO_TIME32_H */
diff --git a/include/vdso/time64.h b/include/vdso/time64.h
new file mode 100644
index 0000000000..b40cfa2aa3
--- /dev/null
+++ b/include/vdso/time64.h
@@ -0,0 +1,15 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __VDSO_TIME64_H
+#define __VDSO_TIME64_H
+
+/* Parameters used to convert the timespec values: */
+#define MSEC_PER_SEC 1000L
+#define USEC_PER_MSEC 1000L
+#define NSEC_PER_USEC 1000L
+#define NSEC_PER_MSEC 1000000L
+#define USEC_PER_SEC 1000000L
+#define NSEC_PER_SEC 1000000000L
+#define PSEC_PER_SEC 1000000000000LL
+#define FSEC_PER_SEC 1000000000000000LL
+
+#endif /* __VDSO_TIME64_H */
diff --git a/include/vdso/vsyscall.h b/include/vdso/vsyscall.h
new file mode 100644
index 0000000000..b0fdc9c6bf
--- /dev/null
+++ b/include/vdso/vsyscall.h
@@ -0,0 +1,14 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __VDSO_VSYSCALL_H
+#define __VDSO_VSYSCALL_H
+
+#ifndef __ASSEMBLY__
+
+#include <asm/vdso/vsyscall.h>
+
+unsigned long vdso_update_begin(void);
+void vdso_update_end(unsigned long flags);
+
+#endif /* !__ASSEMBLY__ */
+
+#endif /* __VDSO_VSYSCALL_H */
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-03 22:49:05 +0000