lib/vdso: Allow to add architecture-specific vdso data (d60d7de3) · Commits · 戴 / test

The initial assumption that all VDSO related data can be completely generic does not hold. S390 needs architecture specific storage to access the clock steering information. Add struct arch_vdso_data to the vdso data struct. For architectures which do not need extra data this defaults to an empty struct. Architectures which require it, enable CONFIG_ARCH_HAS_VDSO_DATA and provide their specific struct in asm/vdso/data.h. Signed-off-by:

Sven Schnelle <svens@linux.ibm.com> Signed-off-by:

Thomas Gleixner <tglx@linutronix.de> Link: https://lkml.kernel.org/r/20200804150124.41692-2-svens@linux.ibm.com

arch/Kconfig

+3 −0

Original line number	Diff line number	Diff line
		@@ -975,6 +975,9 @@ config HAVE_SPARSE_SYSCALL_NR
		entries at 4000, 5000 and 6000 locations. This option turns on syscall
		related optimizations for a given architecture.

		config ARCH_HAS_VDSO_DATA
		bool

		source "kernel/gcov/Kconfig"

		source "scripts/gcc-plugins/Kconfig"

include/vdso/datapage.h

+10 −0

Original line number	Diff line number	Diff line
		@@ -19,6 +19,12 @@
		#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) \| \
		@@ -64,6 +70,8 @@ struct vdso_timestamp {
		* @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.
		@@ -97,6 +105,8 @@ struct vdso_data {
		s32 tz_dsttime;
		u32 hrtimer_res;
		u32 __unused;

		struct arch_vdso_data arch_data;
		};

		/*

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