1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _ASM_X86_KVM_PAGE_TRACK_H
3#define _ASM_X86_KVM_PAGE_TRACK_H
4
5enum kvm_page_track_mode {
6 KVM_PAGE_TRACK_WRITE,
7 KVM_PAGE_TRACK_MAX,
8};
9
10/*
11 * The notifier represented by @kvm_page_track_notifier_node is linked into
12 * the head which will be notified when guest is triggering the track event.
13 *
14 * Write access on the head is protected by kvm->mmu_lock, read access
15 * is protected by track_srcu.
16 */
17struct kvm_page_track_notifier_head {
18 struct srcu_struct track_srcu;
19 struct hlist_head track_notifier_list;
20};
21
22struct kvm_page_track_notifier_node {
23 struct hlist_node node;
24
25 /*
26 * It is called when guest is writing the write-tracked page
27 * and write emulation is finished at that time.
28 *
29 * @vcpu: the vcpu where the write access happened.
30 * @gpa: the physical address written by guest.
31 * @new: the data was written to the address.
32 * @bytes: the written length.
33 * @node: this node
34 */
35 void (*track_write)(struct kvm_vcpu *vcpu, gpa_t gpa, const u8 *new,
36 int bytes, struct kvm_page_track_notifier_node *node);
37 /*
38 * It is called when memory slot is being moved or removed
39 * users can drop write-protection for the pages in that memory slot
40 *
41 * @kvm: the kvm where memory slot being moved or removed
42 * @slot: the memory slot being moved or removed
43 * @node: this node
44 */
45 void (*track_flush_slot)(struct kvm *kvm, struct kvm_memory_slot *slot,
46 struct kvm_page_track_notifier_node *node);
47};
48
49void kvm_page_track_init(struct kvm *kvm);
50void kvm_page_track_cleanup(struct kvm *kvm);
51
52void kvm_page_track_free_memslot(struct kvm_memory_slot *free,
53 struct kvm_memory_slot *dont);
54int kvm_page_track_create_memslot(struct kvm_memory_slot *slot,
55 unsigned long npages);
56
57void kvm_slot_page_track_add_page(struct kvm *kvm,
58 struct kvm_memory_slot *slot, gfn_t gfn,
59 enum kvm_page_track_mode mode);
60void kvm_slot_page_track_remove_page(struct kvm *kvm,
61 struct kvm_memory_slot *slot, gfn_t gfn,
62 enum kvm_page_track_mode mode);
63bool kvm_page_track_is_active(struct kvm_vcpu *vcpu, gfn_t gfn,
64 enum kvm_page_track_mode mode);
65
66void
67kvm_page_track_register_notifier(struct kvm *kvm,
68 struct kvm_page_track_notifier_node *n);
69void
70kvm_page_track_unregister_notifier(struct kvm *kvm,
71 struct kvm_page_track_notifier_node *n);
72void kvm_page_track_write(struct kvm_vcpu *vcpu, gpa_t gpa, const u8 *new,
73 int bytes);
74void kvm_page_track_flush_slot(struct kvm *kvm, struct kvm_memory_slot *slot);
75#endif
76