On Sat, Feb 26, 2022, Sean Christopherson wrote:
> Refactor __tdp_mmu_set_spte() to work with raw values instead of a
> tdp_iter objects so that a future patch can modify SPTEs without doing a
> walk, and without having to synthesize a tdp_iter.
>
> No functional change intended.
>
> Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
> Reviewed-by: Ben Gardon <bgardon@xxxxxxxxxx>
Reviewed-by: Mingwei Zhang <mizhang@xxxxxxxxxx>
> ---
> arch/x86/kvm/mmu/tdp_mmu.c | 51 +++++++++++++++++++++++---------------
> 1 file changed, 31 insertions(+), 20 deletions(-)
>
> diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c
> index 1dcdf1a4fcc1..9e8ba6f12ebf 100644
> --- a/arch/x86/kvm/mmu/tdp_mmu.c
> +++ b/arch/x86/kvm/mmu/tdp_mmu.c
> @@ -617,9 +617,13 @@ static inline int tdp_mmu_zap_spte_atomic(struct kvm *kvm,
>
> /*
> * __tdp_mmu_set_spte - Set a TDP MMU SPTE and handle the associated bookkeeping
> - * @kvm: kvm instance
> - * @iter: a tdp_iter instance currently on the SPTE that should be set
> - * @new_spte: The value the SPTE should be set to
> + * @kvm: KVM instance
> + * @as_id: Address space ID, i.e. regular vs. SMM
> + * @sptep: Pointer to the SPTE
> + * @old_spte: The current value of the SPTE
> + * @new_spte: The new value that will be set for the SPTE
> + * @gfn: The base GFN that was (or will be) mapped by the SPTE
> + * @level: The level _containing_ the SPTE (its parent PT's level)
> * @record_acc_track: Notify the MM subsystem of changes to the accessed state
> * of the page. Should be set unless handling an MMU
> * notifier for access tracking. Leaving record_acc_track
> @@ -631,12 +635,10 @@ static inline int tdp_mmu_zap_spte_atomic(struct kvm *kvm,
> * Leaving record_dirty_log unset in that case prevents page
> * writes from being double counted.
> */
> -static inline void __tdp_mmu_set_spte(struct kvm *kvm, struct tdp_iter *iter,
> - u64 new_spte, bool record_acc_track,
> - bool record_dirty_log)
> +static void __tdp_mmu_set_spte(struct kvm *kvm, int as_id, tdp_ptep_t sptep,
> + u64 old_spte, u64 new_spte, gfn_t gfn, int level,
> + bool record_acc_track, bool record_dirty_log)
> {
> - WARN_ON_ONCE(iter->yielded);
> -
> lockdep_assert_held_write(&kvm->mmu_lock);
>
> /*
> @@ -646,39 +648,48 @@ static inline void __tdp_mmu_set_spte(struct kvm *kvm, struct tdp_iter *iter,
> * should be used. If operating under the MMU lock in write mode, the
> * use of the removed SPTE should not be necessary.
> */
> - WARN_ON(is_removed_spte(iter->old_spte) || is_removed_spte(new_spte));
> + WARN_ON(is_removed_spte(old_spte) || is_removed_spte(new_spte));
>
> - kvm_tdp_mmu_write_spte(iter->sptep, new_spte);
> + kvm_tdp_mmu_write_spte(sptep, new_spte);
> +
> + __handle_changed_spte(kvm, as_id, gfn, old_spte, new_spte, level, false);
>
> - __handle_changed_spte(kvm, iter->as_id, iter->gfn, iter->old_spte,
> - new_spte, iter->level, false);
> if (record_acc_track)
> - handle_changed_spte_acc_track(iter->old_spte, new_spte,
> - iter->level);
> + handle_changed_spte_acc_track(old_spte, new_spte, level);
> if (record_dirty_log)
> - handle_changed_spte_dirty_log(kvm, iter->as_id, iter->gfn,
> - iter->old_spte, new_spte,
> - iter->level);
> + handle_changed_spte_dirty_log(kvm, as_id, gfn, old_spte,
> + new_spte, level);
> +}
> +
> +static inline void _tdp_mmu_set_spte(struct kvm *kvm, struct tdp_iter *iter,
> + u64 new_spte, bool record_acc_track,
> + bool record_dirty_log)
> +{
> + WARN_ON_ONCE(iter->yielded);
> +
> + __tdp_mmu_set_spte(kvm, iter->as_id, iter->sptep, iter->old_spte,
> + new_spte, iter->gfn, iter->level,
> + record_acc_track, record_dirty_log);
> }
>
> static inline void tdp_mmu_set_spte(struct kvm *kvm, struct tdp_iter *iter,
> u64 new_spte)
> {
> - __tdp_mmu_set_spte(kvm, iter, new_spte, true, true);
> + _tdp_mmu_set_spte(kvm, iter, new_spte, true, true);
> }
>
> static inline void tdp_mmu_set_spte_no_acc_track(struct kvm *kvm,
> struct tdp_iter *iter,
> u64 new_spte)
> {
> - __tdp_mmu_set_spte(kvm, iter, new_spte, false, true);
> + _tdp_mmu_set_spte(kvm, iter, new_spte, false, true);
> }
>
> static inline void tdp_mmu_set_spte_no_dirty_log(struct kvm *kvm,
> struct tdp_iter *iter,
> u64 new_spte)
> {
> - __tdp_mmu_set_spte(kvm, iter, new_spte, true, false);
> + _tdp_mmu_set_spte(kvm, iter, new_spte, true, false);
> }
>
> #define tdp_root_for_each_pte(_iter, _root, _start, _end) \
> --
> 2.35.1.574.g5d30c73bfb-goog
>
