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author | Srikant Patnaik | 2015-01-11 12:28:04 +0530 |
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committer | Srikant Patnaik | 2015-01-11 12:28:04 +0530 |
commit | 871480933a1c28f8a9fed4c4d34d06c439a7a422 (patch) | |
tree | 8718f573808810c2a1e8cb8fb6ac469093ca2784 /arch/x86/include/asm/vvar.h | |
parent | 9d40ac5867b9aefe0722bc1f110b965ff294d30d (diff) | |
download | FOSSEE-netbook-kernel-source-871480933a1c28f8a9fed4c4d34d06c439a7a422.tar.gz FOSSEE-netbook-kernel-source-871480933a1c28f8a9fed4c4d34d06c439a7a422.tar.bz2 FOSSEE-netbook-kernel-source-871480933a1c28f8a9fed4c4d34d06c439a7a422.zip |
Moved, renamed, and deleted files
The original directory structure was scattered and unorganized.
Changes are basically to make it look like kernel structure.
Diffstat (limited to 'arch/x86/include/asm/vvar.h')
-rw-r--r-- | arch/x86/include/asm/vvar.h | 50 |
1 files changed, 50 insertions, 0 deletions
diff --git a/arch/x86/include/asm/vvar.h b/arch/x86/include/asm/vvar.h new file mode 100644 index 00000000..de656ac2 --- /dev/null +++ b/arch/x86/include/asm/vvar.h @@ -0,0 +1,50 @@ +/* + * vvar.h: Shared vDSO/kernel variable declarations + * Copyright (c) 2011 Andy Lutomirski + * Subject to the GNU General Public License, version 2 + * + * 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.) + */ + +/* Base address of vvars. This is not ABI. */ +#define VVAR_ADDRESS (-10*1024*1024 - 4096) + +#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 + +#define DECLARE_VVAR(offset, type, name) \ + static type const * const vvaraddr_ ## name = \ + (void *)(VVAR_ADDRESS + (offset)); + +#define DEFINE_VVAR(type, name) \ + type name \ + __attribute__((section(".vvar_" #name), aligned(16))) + +#define VVAR(name) (*vvaraddr_ ## name) + +#endif + +/* DECLARE_VVAR(offset, type, name) */ + +DECLARE_VVAR(0, volatile unsigned long, jiffies) +DECLARE_VVAR(16, int, vgetcpu_mode) +DECLARE_VVAR(128, struct vsyscall_gtod_data, vsyscall_gtod_data) + +#undef DECLARE_VVAR |