diff options
| author | Haozhong Zhang <haozhong.zhang@intel.com> | 2017-12-20 15:29:28 +0800 |
|---|---|---|
| committer | Radim Krčmář <rkrcmar@redhat.com> | 2018-01-16 16:40:09 +0100 |
| commit | b8d7044bcff7a955257b242515bcf1e5045edd9b (patch) | |
| tree | 8c045960d435ed6797fce6a263da75c75ca729ea /arch/x86/include/asm/pat.h | |
| parent | 05992edc279237d5803d64578e0c72b604970a49 (diff) | |
x86/mm: add a function to check if a pfn is UC/UC-/WC
Check whether the PAT memory type of a pfn cannot be overridden by
MTRR UC memory type, i.e. the PAT memory type is UC, UC- or WC. This
function will be used by KVM to distinguish MMIO pfns and give them
UC memory type in the EPT page tables (on Intel processors, EPT
memory types work like MTRRs).
Signed-off-by: Haozhong Zhang <haozhong.zhang@intel.com>
Reviewed-by: Xiao Guangrong <xiaoguangrong@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Diffstat (limited to 'arch/x86/include/asm/pat.h')
| -rw-r--r-- | arch/x86/include/asm/pat.h | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/arch/x86/include/asm/pat.h b/arch/x86/include/asm/pat.h index 8a3ee355b422..92015c65fa2a 100644 --- a/arch/x86/include/asm/pat.h +++ b/arch/x86/include/asm/pat.h @@ -22,4 +22,6 @@ int io_reserve_memtype(resource_size_t start, resource_size_t end, void io_free_memtype(resource_size_t start, resource_size_t end); +bool pat_pfn_immune_to_uc_mtrr(unsigned long pfn); + #endif /* _ASM_X86_PAT_H */ |