arch/x86/include/asm/kvm_page_track.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef _ASM_X86_KVM_PAGE_TRACK_H
   3 #define _ASM_X86_KVM_PAGE_TRACK_H
   4
   5 enum 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  */
  17 struct kvm_page_track_notifier_head {
  18         struct srcu_struct track_srcu;
  19         struct hlist_head track_notifier_list;
  20 };
  21
  22 struct 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
  49 void kvm_page_track_init(struct kvm *kvm);
  50 void kvm_page_track_cleanup(struct kvm *kvm);
  51
  52 void kvm_page_track_free_memslot(struct kvm_memory_slot *free,
  53                                  struct kvm_memory_slot *dont);
  54 int kvm_page_track_create_memslot(struct kvm_memory_slot *slot,
  55                                   unsigned long npages);
  56
  57 void 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);
  60 void 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);
  63 bool kvm_page_track_is_active(struct kvm_vcpu *vcpu, gfn_t gfn,
  64                               enum kvm_page_track_mode mode);
  65
  66 void
  67 kvm_page_track_register_notifier(struct kvm *kvm,
  68                                  struct kvm_page_track_notifier_node *n);
  69 void
  70 kvm_page_track_unregister_notifier(struct kvm *kvm,
  71                                    struct kvm_page_track_notifier_node *n);
  72 void kvm_page_track_write(struct kvm_vcpu *vcpu, gpa_t gpa, const u8 *new,
  73                           int bytes);
  74 void kvm_page_track_flush_slot(struct kvm *kvm, struct kvm_memory_slot *slot);
  75 #endif