linux_dsm_epyc7002/arch/x86/include/asm/vvar.h
Vincenzo Frascino 7ac8707479 x86/vdso: Switch to generic vDSO implementation
The x86 vDSO library requires some adaptations to take advantage of the
newly introduced generic vDSO library.

Introduce the following changes:
 - Modification of vdso.c to be compliant with the common vdso datapage
 - Use of lib/vdso for gettimeofday

[ tglx: Massaged changelog and cleaned up the function signature formatting ]

Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arch@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-mips@vger.kernel.org
Cc: linux-kselftest@vger.kernel.org
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Mark Salyzyn <salyzyn@android.com>
Cc: Peter Collingbourne <pcc@google.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Dmitry Safonov <0x7f454c46@gmail.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Huw Davies <huw@codeweavers.com>
Cc: Shijith Thotton <sthotton@marvell.com>
Cc: Andre Przywara <andre.przywara@arm.com>
Link: https://lkml.kernel.org/r/20190621095252.32307-23-vincenzo.frascino@arm.com
2019-06-22 21:21:10 +02:00

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C

/* SPDX-License-Identifier: GPL-2.0-only */
/*
* vvar.h: Shared vDSO/kernel variable declarations
* Copyright (c) 2011 Andy Lutomirski
*
* A handful of variables are accessible (read-only) from userspace
* code in the vsyscall page and the vdso. They are declared here.
* Some other file must define them with DEFINE_VVAR.
*
* In normal kernel code, they are used like any other variable.
* In user code, they are accessed through the VVAR macro.
*
* These variables live in a page of kernel data that has an extra RO
* mapping for userspace. Each variable needs a unique offset within
* that page; specify that offset with the DECLARE_VVAR macro. (If
* you mess up, the linker will catch it.)
*/
#ifndef _ASM_X86_VVAR_H
#define _ASM_X86_VVAR_H
#if defined(__VVAR_KERNEL_LDS)
/* The kernel linker script defines its own magic to put vvars in the
* right place.
*/
#define DECLARE_VVAR(offset, type, name) \
EMIT_VVAR(name, offset)
#else
extern char __vvar_page;
#define DECLARE_VVAR(offset, type, name) \
extern type vvar_ ## name[CS_BASES] \
__attribute__((visibility("hidden")));
#define VVAR(name) (vvar_ ## name)
#define DEFINE_VVAR(type, name) \
type name[CS_BASES] \
__attribute__((section(".vvar_" #name), aligned(16))) __visible
#endif
/* DECLARE_VVAR(offset, type, name) */
DECLARE_VVAR(128, struct vdso_data, _vdso_data)
#undef DECLARE_VVAR
#endif