1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __KVM_X86_MMU_INTERNAL_H
3 #define __KVM_X86_MMU_INTERNAL_H
4
5 #include <linux/types.h>
6 #include <linux/kvm_host.h>
7 #include <asm/kvm_host.h>
8
9 #undef MMU_DEBUG
10
11 #ifdef MMU_DEBUG
12 extern bool dbg;
13
14 #define pgprintk(x...) do { if (dbg) printk(x); } while (0)
15 #define rmap_printk(x...) do { if (dbg) printk(x); } while (0)
16 #define MMU_WARN_ON(x) WARN_ON(x)
17 #else
18 #define pgprintk(x...) do { } while (0)
19 #define rmap_printk(x...) do { } while (0)
20 #define MMU_WARN_ON(x) do { } while (0)
21 #endif
22
23 struct kvm_mmu_page {
24 struct list_head link;
25 struct hlist_node hash_link;
26 struct list_head lpage_disallowed_link;
27
28 bool unsync;
29 u8 mmu_valid_gen;
30 bool mmio_cached;
31 bool lpage_disallowed; /* Can't be replaced by an equiv large page */
32
33 /*
34 * The following two entries are used to key the shadow page in the
35 * hash table.
36 */
37 union kvm_mmu_page_role role;
38 gfn_t gfn;
39
40 u64 *spt;
41 /* hold the gfn of each spte inside spt */
42 gfn_t *gfns;
43 int root_count; /* Currently serving as active root */
44 unsigned int unsync_children;
45 struct kvm_rmap_head parent_ptes; /* rmap pointers to parent sptes */
46 DECLARE_BITMAP(unsync_child_bitmap, 512);
47
48 #ifdef CONFIG_X86_32
49 /*
50 * Used out of the mmu-lock to avoid reading spte values while an
51 * update is in progress; see the comments in __get_spte_lockless().
52 */
53 int clear_spte_count;
54 #endif
55
56 /* Number of writes since the last time traversal visited this page. */
57 atomic_t write_flooding_count;
58
59 bool tdp_mmu_page;
60 };
61
62 extern struct kmem_cache *mmu_page_header_cache;
63
to_shadow_page(hpa_t shadow_page)64 static inline struct kvm_mmu_page *to_shadow_page(hpa_t shadow_page)
65 {
66 struct page *page = pfn_to_page(shadow_page >> PAGE_SHIFT);
67
68 return (struct kvm_mmu_page *)page_private(page);
69 }
70
sptep_to_sp(u64 * sptep)71 static inline struct kvm_mmu_page *sptep_to_sp(u64 *sptep)
72 {
73 return to_shadow_page(__pa(sptep));
74 }
75
kvm_vcpu_ad_need_write_protect(struct kvm_vcpu * vcpu)76 static inline bool kvm_vcpu_ad_need_write_protect(struct kvm_vcpu *vcpu)
77 {
78 /*
79 * When using the EPT page-modification log, the GPAs in the log
80 * would come from L2 rather than L1. Therefore, we need to rely
81 * on write protection to record dirty pages. This also bypasses
82 * PML, since writes now result in a vmexit.
83 */
84 return vcpu->arch.mmu == &vcpu->arch.guest_mmu;
85 }
86
87 bool is_nx_huge_page_enabled(void);
88 bool mmu_need_write_protect(struct kvm_vcpu *vcpu, gfn_t gfn,
89 bool can_unsync);
90
91 void kvm_mmu_gfn_disallow_lpage(struct kvm_memory_slot *slot, gfn_t gfn);
92 void kvm_mmu_gfn_allow_lpage(struct kvm_memory_slot *slot, gfn_t gfn);
93 bool kvm_mmu_slot_gfn_write_protect(struct kvm *kvm,
94 struct kvm_memory_slot *slot, u64 gfn);
95 void kvm_flush_remote_tlbs_with_address(struct kvm *kvm,
96 u64 start_gfn, u64 pages);
97
kvm_mmu_get_root(struct kvm * kvm,struct kvm_mmu_page * sp)98 static inline void kvm_mmu_get_root(struct kvm *kvm, struct kvm_mmu_page *sp)
99 {
100 BUG_ON(!sp->root_count);
101 lockdep_assert_held(&kvm->mmu_lock);
102
103 ++sp->root_count;
104 }
105
kvm_mmu_put_root(struct kvm * kvm,struct kvm_mmu_page * sp)106 static inline bool kvm_mmu_put_root(struct kvm *kvm, struct kvm_mmu_page *sp)
107 {
108 lockdep_assert_held(&kvm->mmu_lock);
109 --sp->root_count;
110
111 return !sp->root_count;
112 }
113
114 /*
115 * Return values of handle_mmio_page_fault, mmu.page_fault, and fast_page_fault().
116 *
117 * RET_PF_RETRY: let CPU fault again on the address.
118 * RET_PF_EMULATE: mmio page fault, emulate the instruction directly.
119 * RET_PF_INVALID: the spte is invalid, let the real page fault path update it.
120 * RET_PF_FIXED: The faulting entry has been fixed.
121 * RET_PF_SPURIOUS: The faulting entry was already fixed, e.g. by another vCPU.
122 */
123 enum {
124 RET_PF_RETRY = 0,
125 RET_PF_EMULATE,
126 RET_PF_INVALID,
127 RET_PF_FIXED,
128 RET_PF_SPURIOUS,
129 };
130
131 /* Bits which may be returned by set_spte() */
132 #define SET_SPTE_WRITE_PROTECTED_PT BIT(0)
133 #define SET_SPTE_NEED_REMOTE_TLB_FLUSH BIT(1)
134 #define SET_SPTE_SPURIOUS BIT(2)
135
136 int kvm_mmu_hugepage_adjust(struct kvm_vcpu *vcpu, gfn_t gfn,
137 int max_level, kvm_pfn_t *pfnp,
138 bool huge_page_disallowed, int *req_level);
139 void disallowed_hugepage_adjust(u64 spte, gfn_t gfn, int cur_level,
140 kvm_pfn_t *pfnp, int *goal_levelp);
141
142 bool is_nx_huge_page_enabled(void);
143
144 void *mmu_memory_cache_alloc(struct kvm_mmu_memory_cache *mc);
145
146 void account_huge_nx_page(struct kvm *kvm, struct kvm_mmu_page *sp);
147 void unaccount_huge_nx_page(struct kvm *kvm, struct kvm_mmu_page *sp);
148
149 #endif /* __KVM_X86_MMU_INTERNAL_H */
150