diff options
| author | Stefani Seibold <stefani@seibold.net> | 2014-03-17 23:22:10 +0100 |
|---|---|---|
| committer | H. Peter Anvin <hpa@linux.intel.com> | 2014-03-18 12:52:41 -0700 |
| commit | 7c03156f34d113f885f045d8fb8cc3efd9e64751 (patch) | |
| tree | 4d63bb06f639e77cbb09c2d74f295148946ce3f0 /arch/x86/vdso/vdso32 | |
| parent | 7a59ed415f5b57469e22e41fc4188d5399e0b194 (diff) | |
x86, vdso: Add 32 bit VDSO time support for 64 bit kernel
This patch add the VDSO time support for the IA32 Emulation Layer.
Due the nature of the kernel headers and the LP64 compiler where the
size of a long and a pointer differs against a 32 bit compiler, there
is some type hacking necessary for optimal performance.
The vsyscall_gtod_data struture must be a rearranged to serve 32- and
64-bit code access at the same time:
- The seqcount_t was replaced by an unsigned, this makes the
vsyscall_gtod_data intedepend of kernel configuration and internal functions.
- All kernel internal structures are replaced by fix size elements
which works for 32- and 64-bit access
- The inner struct clock was removed to pack the whole struct.
The "unsigned seq" would be handled by functions derivated from seqcount_t.
Signed-off-by: Stefani Seibold <stefani@seibold.net>
Link: http://lkml.kernel.org/r/1395094933-14252-11-git-send-email-stefani@seibold.net
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Diffstat (limited to 'arch/x86/vdso/vdso32')
| -rw-r--r-- | arch/x86/vdso/vdso32/vclock_gettime.c | 21 |
1 files changed, 21 insertions, 0 deletions
diff --git a/arch/x86/vdso/vdso32/vclock_gettime.c b/arch/x86/vdso/vdso32/vclock_gettime.c index ca65e4213d63..175cc72c0f68 100644 --- a/arch/x86/vdso/vdso32/vclock_gettime.c +++ b/arch/x86/vdso/vdso32/vclock_gettime.c @@ -6,4 +6,25 @@ #undef CONFIG_X86_PPRO_FENCE +#ifdef CONFIG_X86_64 + +/* + * in case of a 32 bit VDSO for a 64 bit kernel fake a 32 bit kernel + * configuration + */ +#undef CONFIG_64BIT +#undef CONFIG_X86_64 +#undef CONFIG_ILLEGAL_POINTER_VALUE +#undef CONFIG_SPARSEMEM_VMEMMAP +#undef CONFIG_NR_CPUS + +#define CONFIG_X86_32 1 +#define CONFIG_PAGE_OFFSET 0 +#define CONFIG_ILLEGAL_POINTER_VALUE 0 +#define CONFIG_NR_CPUS 1 + +#define BUILD_VDSO32_64 + +#endif + #include "../vclock_gettime.c" |