linux_dsm_epyc7002/arch/x86/include/asm/pat.h
Haozhong Zhang b8d7044bcf 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>
2018-01-16 16:40:09 +01:00

28 lines
768 B
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_X86_PAT_H
#define _ASM_X86_PAT_H
#include <linux/types.h>
#include <asm/pgtable_types.h>
bool pat_enabled(void);
void pat_disable(const char *reason);
extern void pat_init(void);
extern void init_cache_modes(void);
extern int reserve_memtype(u64 start, u64 end,
enum page_cache_mode req_pcm, enum page_cache_mode *ret_pcm);
extern int free_memtype(u64 start, u64 end);
extern int kernel_map_sync_memtype(u64 base, unsigned long size,
enum page_cache_mode pcm);
int io_reserve_memtype(resource_size_t start, resource_size_t end,
enum page_cache_mode *pcm);
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 */