Re: [PATCH 1/3] KVM: only retrieve memslots once when initializing cache
From: Radim KrÄmÃÅ
Date: Thu Feb 16 2017 - 11:31:54 EST
2017-02-15 23:00+0100, Paolo Bonzini:
> This will make it a bit simpler to handle multiple address spaces
> in gfn_to_hva_cache.
>
> Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
> ---
Reviewed-by: Radim KrÄmÃÅ <rkrcmar@xxxxxxxxxx>
> virt/kvm/kvm_main.c | 21 ++++++++++++++-------
> 1 file changed, 14 insertions(+), 7 deletions(-)
>
> diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
> index 482612b4e496..e21bac7ed5d3 100644
> --- a/virt/kvm/kvm_main.c
> +++ b/virt/kvm/kvm_main.c
> @@ -1937,10 +1937,10 @@ int kvm_vcpu_write_guest(struct kvm_vcpu *vcpu, gpa_t gpa, const void *data,
> }
> EXPORT_SYMBOL_GPL(kvm_vcpu_write_guest);
>
> -int kvm_gfn_to_hva_cache_init(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
> - gpa_t gpa, unsigned long len)
> +static int __kvm_gfn_to_hva_cache_init(struct kvm_memslots *slots,
> + struct gfn_to_hva_cache *ghc,
> + gpa_t gpa, unsigned long len)
> {
> - struct kvm_memslots *slots = kvm_memslots(kvm);
> int offset = offset_in_page(gpa);
> gfn_t start_gfn = gpa >> PAGE_SHIFT;
> gfn_t end_gfn = (gpa + len - 1) >> PAGE_SHIFT;
> @@ -1950,7 +1950,7 @@ int kvm_gfn_to_hva_cache_init(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
> ghc->gpa = gpa;
> ghc->generation = slots->generation;
> ghc->len = len;
> - ghc->memslot = gfn_to_memslot(kvm, start_gfn);
> + ghc->memslot = __gfn_to_memslot(slots, start_gfn);
> ghc->hva = gfn_to_hva_many(ghc->memslot, start_gfn, NULL);
> if (!kvm_is_error_hva(ghc->hva) && nr_pages_needed <= 1) {
> ghc->hva += offset;
> @@ -1960,7 +1960,7 @@ int kvm_gfn_to_hva_cache_init(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
> * verify that the entire region is valid here.
> */
> while (start_gfn <= end_gfn) {
> - ghc->memslot = gfn_to_memslot(kvm, start_gfn);
> + ghc->memslot = __gfn_to_memslot(slots, start_gfn);
> ghc->hva = gfn_to_hva_many(ghc->memslot, start_gfn,
> &nr_pages_avail);
> if (kvm_is_error_hva(ghc->hva))
> @@ -1972,6 +1972,13 @@ int kvm_gfn_to_hva_cache_init(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
> }
> return 0;
> }
> +
> +int kvm_gfn_to_hva_cache_init(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
> + gpa_t gpa, unsigned long len)
> +{
> + struct kvm_memslots *slots = kvm_memslots(kvm);
> + return __kvm_gfn_to_hva_cache_init(slots, ghc, gpa, len);
> +}
> EXPORT_SYMBOL_GPL(kvm_gfn_to_hva_cache_init);
>
> int kvm_write_guest_offset_cached(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
> @@ -1984,7 +1991,7 @@ int kvm_write_guest_offset_cached(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
> BUG_ON(len + offset > ghc->len);
>
> if (slots->generation != ghc->generation)
> - kvm_gfn_to_hva_cache_init(kvm, ghc, ghc->gpa, ghc->len);
> + __kvm_gfn_to_hva_cache_init(slots, ghc, ghc->gpa, ghc->len);
>
> if (unlikely(!ghc->memslot))
> return kvm_write_guest(kvm, gpa, data, len);
> @@ -2017,7 +2024,7 @@ int kvm_read_guest_cached(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
> BUG_ON(len > ghc->len);
>
> if (slots->generation != ghc->generation)
> - kvm_gfn_to_hva_cache_init(kvm, ghc, ghc->gpa, ghc->len);
> + __kvm_gfn_to_hva_cache_init(slots, ghc, ghc->gpa, ghc->len);
>
> if (unlikely(!ghc->memslot))
> return kvm_read_guest(kvm, ghc->gpa, data, len);
> --
> 1.8.3.1
>
>