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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 /include/vdso/datapage.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 ...
Diffstat (limited to 'include/vdso/datapage.h')
-rw-r--r--include/vdso/datapage.h202
1 files changed, 202 insertions, 0 deletions
diff --git a/include/vdso/datapage.h b/include/vdso/datapage.h
new file mode 100644
index 000000000..09897f76a
--- /dev/null
+++ b/include/vdso/datapage.h
@@ -0,0 +1,202 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __VDSO_DATAPAGE_H
+#define __VDSO_DATAPAGE_H
+
+#ifndef __ASSEMBLER__
+
+#include <linux/types.h>
+
+#include <uapi/linux/bits.h>
+#include <uapi/linux/time.h>
+
+#include <vdso/align.h>
+#include <vdso/bits.h>
+#include <vdso/cache.h>
+#include <vdso/page.h>
+#include <vdso/time.h>
+
+#ifdef CONFIG_ARCH_HAS_VDSO_TIME_DATA
+#include <asm/vdso/time_data.h>
+#else
+struct arch_vdso_time_data {};
+#endif
+
+#if defined(CONFIG_ARCH_HAS_VDSO_ARCH_DATA)
+#include <asm/vdso/arch_data.h>
+#else
+struct vdso_arch_data {
+ /* Needed for the generic code, never actually used at runtime */
+ char __unused;
+};
+#endif
+
+#define VDSO_BASES (CLOCK_TAI + 1)
+#define VDSO_BASE_AUX 0
+#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 VDSO_AUX __GENMASK(CLOCK_AUX_LAST, CLOCK_AUX)
+
+#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_time_data.cycle_last. For coarse clocks this encodes
+ * the actual time.
+ *
+ * To be noticed that for highres clocks nsec is left-shifted by
+ * vdso_time_data[x].shift.
+ */
+struct vdso_timestamp {
+ u64 sec;
+ u64 nsec;
+};
+
+/**
+ * struct vdso_clock - vdso per clocksource datapage representation
+ * @seq: timebase sequence counter
+ * @clock_mode: clock mode
+ * @cycle_last: timebase at clocksource init
+ * @max_cycles: maximum cycles which won't overflow 64bit multiplication
+ * @mask: clocksource mask
+ * @mult: clocksource multiplier
+ * @shift: clocksource shift
+ * @basetime: basetime per clock_id
+ * @offset: time namespace offset per clock_id
+ *
+ * See also struct vdso_time_data for basic access and ordering information as
+ * struct vdso_clock is used there.
+ *
+ * @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_clock {
+ u32 seq;
+
+ s32 clock_mode;
+ u64 cycle_last;
+#ifdef CONFIG_GENERIC_VDSO_OVERFLOW_PROTECT
+ u64 max_cycles;
+#endif
+ u64 mask;
+ u32 mult;
+ u32 shift;
+
+ union {
+ struct vdso_timestamp basetime[VDSO_BASES];
+ struct timens_offset offset[VDSO_BASES];
+ };
+};
+
+/**
+ * struct vdso_time_data - vdso datapage representation
+ * @arch_data: architecture specific data (optional, defaults
+ * to an empty struct)
+ * @clock_data: clocksource related data (array)
+ * @aux_clock_data: auxiliary clocksource related data (array)
+ * @tz_minuteswest: minutes west of Greenwich
+ * @tz_dsttime: type of DST correction
+ * @hrtimer_res: hrtimer resolution
+ * @__unused: unused
+ *
+ * vdso_time_data will be accessed by 64 bit and compat code at the same time
+ * so we should be careful before modifying this structure.
+ *
+ * The ordering of the struct members is optimized to have fast acces to the
+ * often required struct members which are related to CLOCK_REALTIME and
+ * CLOCK_MONOTONIC. This information is stored in the first cache lines.
+ */
+struct vdso_time_data {
+ struct arch_vdso_time_data arch_data;
+
+ struct vdso_clock clock_data[CS_BASES];
+ struct vdso_clock aux_clock_data[MAX_AUX_CLOCKS];
+
+ s32 tz_minuteswest;
+ s32 tz_dsttime;
+ u32 hrtimer_res;
+ u32 __unused;
+} ____cacheline_aligned;
+
+/**
+ * struct vdso_rng_data - vdso RNG state information
+ * @generation: counter representing the number of RNG reseeds
+ * @is_ready: boolean signaling whether the RNG is initialized
+ */
+struct vdso_rng_data {
+ u64 generation;
+ u8 is_ready;
+};
+
+/*
+ * 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_time_data vdso_u_time_data __attribute__((visibility("hidden")));
+extern struct vdso_rng_data vdso_u_rng_data __attribute__((visibility("hidden")));
+extern struct vdso_arch_data vdso_u_arch_data __attribute__((visibility("hidden")));
+
+extern struct vdso_time_data *vdso_k_time_data;
+extern struct vdso_rng_data *vdso_k_rng_data;
+extern struct vdso_arch_data *vdso_k_arch_data;
+
+#define VDSO_ARCH_DATA_SIZE ALIGN(sizeof(struct vdso_arch_data), PAGE_SIZE)
+#define VDSO_ARCH_DATA_PAGES (VDSO_ARCH_DATA_SIZE >> PAGE_SHIFT)
+
+enum vdso_pages {
+ VDSO_TIME_PAGE_OFFSET,
+ VDSO_TIMENS_PAGE_OFFSET,
+ VDSO_RNG_PAGE_OFFSET,
+ VDSO_ARCH_PAGES_START,
+ VDSO_ARCH_PAGES_END = VDSO_ARCH_PAGES_START + VDSO_ARCH_DATA_PAGES - 1,
+ VDSO_NR_PAGES
+};
+
+#else /* !__ASSEMBLER__ */
+
+#ifdef CONFIG_VDSO_GETRANDOM
+#define __vdso_u_rng_data PROVIDE(vdso_u_rng_data = vdso_u_data + 2 * PAGE_SIZE);
+#else
+#define __vdso_u_rng_data
+#endif
+
+#ifdef CONFIG_ARCH_HAS_VDSO_ARCH_DATA
+#define __vdso_u_arch_data PROVIDE(vdso_u_arch_data = vdso_u_data + 3 * PAGE_SIZE);
+#else
+#define __vdso_u_arch_data
+#endif
+
+#define VDSO_VVAR_SYMS \
+ PROVIDE(vdso_u_data = . - __VDSO_PAGES * PAGE_SIZE); \
+ PROVIDE(vdso_u_time_data = vdso_u_data); \
+ __vdso_u_rng_data \
+ __vdso_u_arch_data \
+
+
+#endif /* !__ASSEMBLER__ */
+
+#endif /* __VDSO_DATAPAGE_H */