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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-23 13:28:57 -0700
commit4352b8aee98005853aa63f57d6377282de17a33f (patch)
tree27614d7a9ef05c32d089004e104364ce42324837 /fs/ntfs/time.h
downloadlinux-stable-4352b8aee98005853aa63f57d6377282de17a33f.tar.gz
linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.zip
Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted
Pull I3C updates from Alexandre Belloni: "A new driver this cycle, for the AMD AXI I3C controller. There are also new features such as IBI wakeup support, SETAASA device discovery and ACPI support for the the DAA methods, meaning we can now communicate with the SPD devices on DDR5 modules. New driver: - AMD AXI I3C master controller Subsystem: - I3C Common Command Code (CCC) handling improvements, especially around GET CCCs - SETAASA device discovery support - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as well as I2C devices on I3C bus - IBI-based wakeup support Drivers: - dw: SETAASA support - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C controller support, PIO queue management support for HCI v1.2 - renesas: improve suspend to RAM support, add runtime PM support" * tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits) i3c: dw: reduce do_daa time if there's no client i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2 i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode i3c: dw: rename "pclk" to "apb" to match dt-binding i3c: dw: make struct dw_i3c_cmd smaller i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding i3c: renesas: Don't register devices when ENTDAA times out i3c: master: dw-i3c-master: fix OD timing for first broadcast i3c: mipi-i3c-hci: Advertise IBI wakeup capability i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev() i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI i3c: master: Reject IBI requests from non-IBI-capable devices i3c: master: Add helper to query bus wakeup requirements i3c: master: Report wakeup events for IBIs i3c: master: Support IBI-based wakeup capability i3c: master: Fix potential UAF in i3c_device_match() i3c: master: Fix potential UAF in i3c_device_uevent() i3c: Make dev->desc locking assumptions explicit i3c: master: Fix use-after-free of master->this ...
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diff --git a/fs/ntfs/time.h b/fs/ntfs/time.h
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+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * NTFS time conversion functions.
+ *
+ * Copyright (c) 2001-2005 Anton Altaparmakov
+ */
+
+#ifndef _LINUX_NTFS_TIME_H
+#define _LINUX_NTFS_TIME_H
+
+#include <linux/time.h>
+#include <asm/div64.h> /* For do_div(). */
+
+#define NTFS_TIME_OFFSET ((s64)(369 * 365 + 89) * 24 * 3600)
+
+/*
+ * utc2ntfs - convert Linux UTC time to NTFS time
+ * @ts: Linux UTC time to convert to NTFS time
+ *
+ * Convert the Linux UTC time @ts to its corresponding NTFS time and return
+ * that in little endian format.
+ *
+ * Linux stores time in a struct timespec64 consisting of a time64_t tv_sec
+ * and a long tv_nsec where tv_sec is the number of 1-second intervals since
+ * 1st January 1970, 00:00:00 UTC and tv_nsec is the number of 1-nano-second
+ * intervals since the value of tv_sec.
+ *
+ * NTFS uses Microsoft's standard time format which is stored in a s64 and is
+ * measured as the number of 100-nano-second intervals since 1st January 1601,
+ * 00:00:00 UTC.
+ */
+static inline __le64 utc2ntfs(const struct timespec64 ts)
+{
+ /*
+ * Convert the seconds to 100ns intervals, add the nano-seconds
+ * converted to 100ns intervals, and then add the NTFS time offset.
+ */
+ return cpu_to_le64((u64)(ts.tv_sec + NTFS_TIME_OFFSET) * 10000000 +
+ ts.tv_nsec / 100);
+}
+
+/*
+ * get_current_ntfs_time - get the current time in little endian NTFS format
+ *
+ * Get the current time from the Linux kernel, convert it to its corresponding
+ * NTFS time and return that in little endian format.
+ */
+static inline __le64 get_current_ntfs_time(void)
+{
+ struct timespec64 ts;
+
+ ktime_get_coarse_real_ts64(&ts);
+ return utc2ntfs(ts);
+}
+
+/*
+ * ntfs2utc - convert NTFS time to Linux time
+ * @time: NTFS time (little endian) to convert to Linux UTC
+ *
+ * Convert the little endian NTFS time @time to its corresponding Linux UTC
+ * time and return that in cpu format.
+ *
+ * Linux stores time in a struct timespec64 consisting of a time64_t tv_sec
+ * and a long tv_nsec where tv_sec is the number of 1-second intervals since
+ * 1st January 1970, 00:00:00 UTC and tv_nsec is the number of 1-nano-second
+ * intervals since the value of tv_sec.
+ *
+ * NTFS uses Microsoft's standard time format which is stored in a s64 and is
+ * measured as the number of 100 nano-second intervals since 1st January 1601,
+ * 00:00:00 UTC.
+ */
+static inline struct timespec64 ntfs2utc(const __le64 time)
+{
+ struct timespec64 ts;
+ s32 t32;
+
+ /* Subtract the NTFS time offset. */
+ s64 t = le64_to_cpu(time) - NTFS_TIME_OFFSET * 10000000;
+ /*
+ * Convert the time to 1-second intervals and the remainder to
+ * 1-nano-second intervals.
+ */
+ ts.tv_sec = div_s64_rem(t, 10000000, &t32);
+ ts.tv_nsec = t32 * 100;
+ return ts;
+}
+#endif /* _LINUX_NTFS_TIME_H */