text: // SPDX-License-Identifier: GPL-2.0
  
  #ifndef __KVM_X86_MMU_TDP_MMU_H
  #define __KVM_X86_MMU_TDP_MMU_H
  
  #include <linux/kvm_host.h>
  
  hpa_t kvm_tdp_mmu_get_vcpu_root_hpa(struct kvm_vcpu *vcpu);
  
  __must_check static inline bool kvm_tdp_mmu_get_root(struct kvm *kvm,
  						     struct kvm_mmu_page *root)
  {
  	if (root->role.invalid)
  		return false;
  
  	return refcount_inc_not_zero(&root->tdp_mmu_root_count);
  }
  
  void kvm_tdp_mmu_put_root(struct kvm *kvm, struct kvm_mmu_page *root,
  			  bool shared);
  
  bool __kvm_tdp_mmu_zap_gfn_range(struct kvm *kvm, int as_id, gfn_t start,
  				 gfn_t end, bool can_yield, bool flush);
  static inline bool kvm_tdp_mmu_zap_gfn_range(struct kvm *kvm, int as_id,
  					     gfn_t start, gfn_t end, bool flush)
  {
  	return __kvm_tdp_mmu_zap_gfn_range(kvm, as_id, start, end, true, flush);
  }
  static inline bool kvm_tdp_mmu_zap_sp(struct kvm *kvm, struct kvm_mmu_page *sp)
  {
  	gfn_t end = sp->gfn + KVM_PAGES_PER_HPAGE(sp->role.level + 1);
  
  	/*
  	 * Don't allow yielding, as the caller may have a flush pending.  Note,
  	 * if mmu_lock is held for write, zapping will never yield in this case,
  	 * but explicitly disallow it for safety.  The TDP MMU does not yield
  	 * until it has made forward progress (steps sideways), and when zapping
  	 * a single shadow page that it's guaranteed to see (thus the mmu_lock
  	 * requirement), its "step sideways" will always step beyond the bounds
  	 * of the shadow page's gfn range and stop iterating before yielding.
  	 */
  	lockdep_assert_held_write(&kvm->mmu_lock);
  	return __kvm_tdp_mmu_zap_gfn_range(kvm, kvm_mmu_page_as_id(sp),
  					   sp->gfn, end, false, false);
  }
  
  void kvm_tdp_mmu_zap_all(struct kvm *kvm);
  void kvm_tdp_mmu_invalidate_all_roots(struct kvm *kvm);
  void kvm_tdp_mmu_zap_invalidated_roots(struct kvm *kvm);
  
  int kvm_tdp_mmu_map(struct kvm_vcpu *vcpu, gpa_t gpa, u32 error_code,
  		    int map_writable, int max_level, kvm_pfn_t pfn,
  		    bool prefault);
  
  bool kvm_tdp_mmu_unmap_gfn_range(struct kvm *kvm, struct kvm_gfn_range *range,
  				 bool flush);
  bool kvm_tdp_mmu_age_gfn_range(struct kvm *kvm, struct kvm_gfn_range *range);
  bool kvm_tdp_mmu_test_age_gfn(struct kvm *kvm, struct kvm_gfn_range *range);
  bool kvm_tdp_mmu_set_spte_gfn(struct kvm *kvm, struct kvm_gfn_range *range);
  
  bool kvm_tdp_mmu_wrprot_slot(struct kvm *kvm,
  			     const struct kvm_memory_slot *slot, int min_level);
  bool kvm_tdp_mmu_clear_dirty_slot(struct kvm *kvm,
  				  const struct kvm_memory_slot *slot);
  void kvm_tdp_mmu_clear_dirty_pt_masked(struct kvm *kvm,
  				       struct kvm_memory_slot *slot,
  				       gfn_t gfn, unsigned long mask,
  				       bool wrprot);
  bool kvm_tdp_mmu_zap_collapsible_sptes(struct kvm *kvm,
  				       const struct kvm_memory_slot *slot,
  				       bool flush);
  
  bool kvm_tdp_mmu_write_protect_gfn(struct kvm *kvm,
  				   struct kvm_memory_slot *slot, gfn_t gfn,
  				   int min_level);
  
  static inline void kvm_tdp_mmu_walk_lockless_begin(void)
  {
  	rcu_read_lock();
  }
  
  static inline void kvm_tdp_mmu_walk_lockless_end(void)
  {
  	rcu_read_unlock();
  }
  
  int kvm_tdp_mmu_get_walk(struct kvm_vcpu *vcpu, u64 addr, u64 *sptes,
  			 int *root_level);
  u64 *kvm_tdp_mmu_fast_pf_get_last_sptep(struct kvm_vcpu *vcpu, u64 addr,
  					u64 *spte);
  
  #ifdef CONFIG_X86_64
  bool kvm_mmu_init_tdp_mmu(struct kvm *kvm);
  void kvm_mmu_uninit_tdp_mmu(struct kvm *kvm);
  static inline bool is_tdp_mmu_enabled(struct kvm *kvm) { return kvm->arch.tdp_mmu_enabled; }
  static inline bool is_tdp_mmu_page(struct kvm_mmu_page *sp) { return sp->tdp_mmu_page; }
  
  static inline bool is_tdp_mmu(struct kvm_mmu *mmu)
  {
  	struct kvm_mmu_page *sp;
  	hpa_t hpa = mmu->root_hpa;
  
  	if (WARN_ON(!VALID_PAGE(hpa)))
  		return false;
  
  	/*
  	 * A NULL shadow page is legal when shadowing a non-paging guest with
  	 * PAE paging, as the MMU will be direct with root_hpa pointing at the
  	 * pae_root page, not a shadow page.
  	 */
  	sp = to_shadow_page(hpa);
  	return sp && is_tdp_mmu_page(sp) && sp->root_count;
  }
  #else
  static inline bool kvm_mmu_init_tdp_mmu(struct kvm *kvm) { return false; }
  static inline void kvm_mmu_uninit_tdp_mmu(struct kvm *kvm) {}
  static inline bool is_tdp_mmu_enabled(struct kvm *kvm) { return false; }
  static inline bool is_tdp_mmu_page(struct kvm_mmu_page *sp) { return false; }
  static inline bool is_tdp_mmu(struct kvm_mmu *mmu) { return false; }
  #endif
  
  #endif /* __KVM_X86_MMU_TDP_MMU_H */
  