xref: /openbmc/linux/arch/x86/kvm/mmu.h (revision 171f1bc7)
1 #ifndef __KVM_X86_MMU_H
2 #define __KVM_X86_MMU_H
3 
4 #include <linux/kvm_host.h>
5 #include "kvm_cache_regs.h"
6 
7 #define PT64_PT_BITS 9
8 #define PT64_ENT_PER_PAGE (1 << PT64_PT_BITS)
9 #define PT32_PT_BITS 10
10 #define PT32_ENT_PER_PAGE (1 << PT32_PT_BITS)
11 
12 #define PT_WRITABLE_SHIFT 1
13 
14 #define PT_PRESENT_MASK (1ULL << 0)
15 #define PT_WRITABLE_MASK (1ULL << PT_WRITABLE_SHIFT)
16 #define PT_USER_MASK (1ULL << 2)
17 #define PT_PWT_MASK (1ULL << 3)
18 #define PT_PCD_MASK (1ULL << 4)
19 #define PT_ACCESSED_SHIFT 5
20 #define PT_ACCESSED_MASK (1ULL << PT_ACCESSED_SHIFT)
21 #define PT_DIRTY_MASK (1ULL << 6)
22 #define PT_PAGE_SIZE_MASK (1ULL << 7)
23 #define PT_PAT_MASK (1ULL << 7)
24 #define PT_GLOBAL_MASK (1ULL << 8)
25 #define PT64_NX_SHIFT 63
26 #define PT64_NX_MASK (1ULL << PT64_NX_SHIFT)
27 
28 #define PT_PAT_SHIFT 7
29 #define PT_DIR_PAT_SHIFT 12
30 #define PT_DIR_PAT_MASK (1ULL << PT_DIR_PAT_SHIFT)
31 
32 #define PT32_DIR_PSE36_SIZE 4
33 #define PT32_DIR_PSE36_SHIFT 13
34 #define PT32_DIR_PSE36_MASK \
35 	(((1ULL << PT32_DIR_PSE36_SIZE) - 1) << PT32_DIR_PSE36_SHIFT)
36 
37 #define PT64_ROOT_LEVEL 4
38 #define PT32_ROOT_LEVEL 2
39 #define PT32E_ROOT_LEVEL 3
40 
41 #define PT_PDPE_LEVEL 3
42 #define PT_DIRECTORY_LEVEL 2
43 #define PT_PAGE_TABLE_LEVEL 1
44 
45 #define PFERR_PRESENT_MASK (1U << 0)
46 #define PFERR_WRITE_MASK (1U << 1)
47 #define PFERR_USER_MASK (1U << 2)
48 #define PFERR_RSVD_MASK (1U << 3)
49 #define PFERR_FETCH_MASK (1U << 4)
50 
51 int kvm_mmu_get_spte_hierarchy(struct kvm_vcpu *vcpu, u64 addr, u64 sptes[4]);
52 void kvm_mmu_set_mmio_spte_mask(u64 mmio_mask);
53 int handle_mmio_page_fault_common(struct kvm_vcpu *vcpu, u64 addr, bool direct);
54 int kvm_init_shadow_mmu(struct kvm_vcpu *vcpu, struct kvm_mmu *context);
55 
56 static inline unsigned int kvm_mmu_available_pages(struct kvm *kvm)
57 {
58 	return kvm->arch.n_max_mmu_pages -
59 		kvm->arch.n_used_mmu_pages;
60 }
61 
62 static inline void kvm_mmu_free_some_pages(struct kvm_vcpu *vcpu)
63 {
64 	if (unlikely(kvm_mmu_available_pages(vcpu->kvm)< KVM_MIN_FREE_MMU_PAGES))
65 		__kvm_mmu_free_some_pages(vcpu);
66 }
67 
68 static inline int kvm_mmu_reload(struct kvm_vcpu *vcpu)
69 {
70 	if (likely(vcpu->arch.mmu.root_hpa != INVALID_PAGE))
71 		return 0;
72 
73 	return kvm_mmu_load(vcpu);
74 }
75 
76 static inline int is_present_gpte(unsigned long pte)
77 {
78 	return pte & PT_PRESENT_MASK;
79 }
80 
81 static inline int is_writable_pte(unsigned long pte)
82 {
83 	return pte & PT_WRITABLE_MASK;
84 }
85 
86 static inline bool is_write_protection(struct kvm_vcpu *vcpu)
87 {
88 	return kvm_read_cr0_bits(vcpu, X86_CR0_WP);
89 }
90 
91 static inline bool check_write_user_access(struct kvm_vcpu *vcpu,
92 					   bool write_fault, bool user_fault,
93 					   unsigned long pte)
94 {
95 	if (unlikely(write_fault && !is_writable_pte(pte)
96 	      && (user_fault || is_write_protection(vcpu))))
97 		return false;
98 
99 	if (unlikely(user_fault && !(pte & PT_USER_MASK)))
100 		return false;
101 
102 	return true;
103 }
104 #endif
105