> - After the guest becomes secure, when we handle a page fault of a page
> belonging to SVM in HV, send that page to UV via UV_PAGE_IN.
> - Whenever a page is unmapped on the HV side, inform UV via UV_PAGE_INVAL.
> - Ensure all those routines that walk the secondary page tables of
> the guest don't do so in case of secure VM. For secure guest, the
> active secondary page tables are in secure memory and the secondary
> page tables in HV are freed when guest becomes secure.
>
> Signed-off-by: Bharata B Rao <bharata@xxxxxxxxxxxxx>
> ---
> arch/powerpc/include/asm/kvm_host.h | 12 ++++++++++++
> arch/powerpc/include/asm/ultravisor-api.h | 1 +
> arch/powerpc/include/asm/ultravisor.h | 5 +++++
> arch/powerpc/kvm/book3s_64_mmu_radix.c | 22 ++++++++++++++++++++++
> arch/powerpc/kvm/book3s_hv_devm.c | 20 ++++++++++++++++++++
> 5 files changed, 60 insertions(+)
>
> diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h
> index 66e5cc8c9759..29333e8de1c4 100644
> --- a/arch/powerpc/include/asm/kvm_host.h
> +++ b/arch/powerpc/include/asm/kvm_host.h
> @@ -867,6 +867,8 @@ static inline void kvm_arch_vcpu_block_finish(struct kvm_vcpu *vcpu) {}
> #ifdef CONFIG_PPC_UV
> extern int kvmppc_devm_init(void);
> extern void kvmppc_devm_free(void);
> +extern bool kvmppc_is_guest_secure(struct kvm *kvm);
> +extern int kvmppc_send_page_to_uv(struct kvm *kvm, unsigned long gpa);
> #else
> static inline int kvmppc_devm_init(void)
> {
> @@ -874,6 +876,16 @@ static inline int kvmppc_devm_init(void)
> }
>
> static inline void kvmppc_devm_free(void) {}
> +
> +static inline bool kvmppc_is_guest_secure(struct kvm *kvm)
> +{
> + return false;
> +}
> +
> +static inline int kvmppc_send_page_to_uv(struct kvm *kvm, unsigned long gpa)
> +{
> + return -EFAULT;
> +}
> #endif /* CONFIG_PPC_UV */
>
> #endif /* __POWERPC_KVM_HOST_H__ */
> diff --git a/arch/powerpc/include/asm/ultravisor-api.h b/arch/powerpc/include/asm/ultravisor-api.h
> index 46b1ee381695..cf200d4ce703 100644
> --- a/arch/powerpc/include/asm/ultravisor-api.h
> +++ b/arch/powerpc/include/asm/ultravisor-api.h
> @@ -29,5 +29,6 @@
> #define UV_UNREGISTER_MEM_SLOT 0xF124
> #define UV_PAGE_IN 0xF128
> #define UV_PAGE_OUT 0xF12C
> +#define UV_PAGE_INVAL 0xF138
>
> #endif /* _ASM_POWERPC_ULTRAVISOR_API_H */
> diff --git a/arch/powerpc/include/asm/ultravisor.h b/arch/powerpc/include/asm/ultravisor.h
> index 719c0c3930b9..b333241bbe4c 100644
> --- a/arch/powerpc/include/asm/ultravisor.h
> +++ b/arch/powerpc/include/asm/ultravisor.h
> @@ -57,4 +57,9 @@ static inline int uv_unregister_mem_slot(u64 lpid, u64 slotid)
> return ucall_norets(UV_UNREGISTER_MEM_SLOT, lpid, slotid);
> }
>
> +static inline int uv_page_inval(u64 lpid, u64 gpa, u64 page_shift)
> +{
> + return ucall_norets(UV_PAGE_INVAL, lpid, gpa, page_shift);
> +}
> +
> #endif /* _ASM_POWERPC_ULTRAVISOR_H */
> diff --git a/arch/powerpc/kvm/book3s_64_mmu_radix.c b/arch/powerpc/kvm/book3s_64_mmu_radix.c
> index 2d415c36a61d..93ad34e63045 100644
> --- a/arch/powerpc/kvm/book3s_64_mmu_radix.c
> +++ b/arch/powerpc/kvm/book3s_64_mmu_radix.c
> @@ -19,6 +19,8 @@
> #include <asm/pgtable.h>
> #include <asm/pgalloc.h>
> #include <asm/pte-walk.h>
> +#include <asm/ultravisor.h>
> +#include <asm/kvm_host.h>
>
> /*
> * Supported radix tree geometry.
> @@ -915,6 +917,9 @@ int kvmppc_book3s_radix_page_fault(struct kvm_run *run, struct kvm_vcpu *vcpu,
> if (!(dsisr & DSISR_PRTABLE_FAULT))
> gpa |= ea & 0xfff;
>
> + if (kvmppc_is_guest_secure(kvm))
> + return kvmppc_send_page_to_uv(kvm, gpa & PAGE_MASK);
> +
> /* Get the corresponding memslot */
> memslot = gfn_to_memslot(kvm, gfn);
>
> @@ -972,6 +977,11 @@ int kvm_unmap_radix(struct kvm *kvm, struct kvm_memory_slot *memslot,
> unsigned long gpa = gfn << PAGE_SHIFT;
> unsigned int shift;
>
> + if (kvmppc_is_guest_secure(kvm)) {
> + uv_page_inval(kvm->arch.lpid, gpa, PAGE_SIZE);
> + return 0;
> + }
If it is a page we share with UV, won't we need to drop the HV mapping
for the page?
> +
> ptep = __find_linux_pte(kvm->arch.pgtable, gpa, NULL, &shift);
> if (ptep && pte_present(*ptep))
> kvmppc_unmap_pte(kvm, ptep, gpa, shift, memslot,
> @@ -989,6 +999,9 @@ int kvm_age_radix(struct kvm *kvm, struct kvm_memory_slot *memslot,
> int ref = 0;
> unsigned long old, *rmapp;
>
> + if (kvmppc_is_guest_secure(kvm))
> + return ref;
> +
> ptep = __find_linux_pte(kvm->arch.pgtable, gpa, NULL, &shift);
> if (ptep && pte_present(*ptep) && pte_young(*ptep)) {
> old = kvmppc_radix_update_pte(kvm, ptep, _PAGE_ACCESSED, 0,
> @@ -1013,6 +1026,9 @@ int kvm_test_age_radix(struct kvm *kvm, struct kvm_memory_slot *memslot,
> unsigned int shift;
> int ref = 0;
>
> + if (kvmppc_is_guest_secure(kvm))
> + return ref;
> +
> ptep = __find_linux_pte(kvm->arch.pgtable, gpa, NULL, &shift);
> if (ptep && pte_present(*ptep) && pte_young(*ptep))
> ref = 1;
> @@ -1030,6 +1046,9 @@ static int kvm_radix_test_clear_dirty(struct kvm *kvm,
> int ret = 0;
> unsigned long old, *rmapp;
>
> + if (kvmppc_is_guest_secure(kvm))
> + return ret;
> +
> ptep = __find_linux_pte(kvm->arch.pgtable, gpa, NULL, &shift);
> if (ptep && pte_present(*ptep) && pte_dirty(*ptep)) {
> ret = 1;
> @@ -1082,6 +1101,9 @@ void kvmppc_radix_flush_memslot(struct kvm *kvm,
> unsigned long gpa;
> unsigned int shift;
>
> + if (kvmppc_is_guest_secure(kvm))
> + return;
> +
> gpa = memslot->base_gfn << PAGE_SHIFT;
> spin_lock(&kvm->mmu_lock);
> for (n = memslot->npages; n; --n) {
> diff --git a/arch/powerpc/kvm/book3s_hv_devm.c b/arch/powerpc/kvm/book3s_hv_devm.c
> index 494495806407..19cfad340a51 100644
> --- a/arch/powerpc/kvm/book3s_hv_devm.c
> +++ b/arch/powerpc/kvm/book3s_hv_devm.c
> @@ -49,6 +49,11 @@ struct kvmppc_devm_page_pvt {
> bool skip_page_out;
> };
>
> +bool kvmppc_is_guest_secure(struct kvm *kvm)
> +{
> + return !!(kvm->arch.secure_guest & KVMPPC_SECURE_INIT_DONE);
> +}
> +
> unsigned long kvmppc_h_svm_init_start(struct kvm *kvm)
> {
> struct kvm_memslots *slots;
> @@ -453,6 +458,21 @@ kvmppc_h_svm_page_out(struct kvm *kvm, unsigned long gpa,
> return ret;
> }
>
> +int kvmppc_send_page_to_uv(struct kvm *kvm, unsigned long gpa)
> +{
> + unsigned long pfn;
> + int ret;
> +
> + pfn = gfn_to_pfn(kvm, gpa >> PAGE_SHIFT);
> + if (is_error_noslot_pfn(pfn))
> + return -EFAULT;
> +
> + ret = uv_page_in(kvm->arch.lpid, pfn << PAGE_SHIFT, gpa, 0, PAGE_SHIFT);
> + kvm_release_pfn_clean(pfn);
> +
> + return (ret == U_SUCCESS) ? RESUME_GUEST : -EFAULT;
> +}
> +
> static u64 kvmppc_get_secmem_size(void)
> {
> struct device_node *np;
> --
> 2.21.0
