linux_dsm_epyc7002/arch/x86/include/asm/vvar.h
Thomas Gleixner 6776e83edb treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 180
Based on 1 normalized pattern(s):

  subject to the gnu general public license version 2

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 4 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Steve Winslow <swinslow@gmail.com>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Armijn Hemel <armijn@tjaldur.nl>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190528170026.343113277@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:29:20 -07:00

52 lines
1.4 KiB
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 __attribute__((visibility("hidden")));
#define VVAR(name) (vvar_ ## name)
#define DEFINE_VVAR(type, name) \
type name \
__attribute__((section(".vvar_" #name), aligned(16))) __visible
#endif
/* DECLARE_VVAR(offset, type, name) */
DECLARE_VVAR(128, struct vsyscall_gtod_data, vsyscall_gtod_data)
#undef DECLARE_VVAR
#endif