From 90165d3da0760a0353518740ac307f0d81c4e400 Mon Sep 17 00:00:00 2001 From: Suraj Jitindar Singh Date: Fri, 21 Dec 2018 14:28:42 +1100 Subject: [PATCH] KVM: PPC: Book3S HV: Introduce kvmhv_update_nest_rmap_rc_list() Introduce a function kvmhv_update_nest_rmap_rc_list() which for a given nest_rmap list will traverse it, find the corresponding pte in the shadow page tables, and if it still maps the same host page update the rc bits accordingly. Signed-off-by: Suraj Jitindar Singh Signed-off-by: Paul Mackerras --- arch/powerpc/include/asm/kvm_book3s.h | 2 + arch/powerpc/include/asm/kvm_book3s_64.h | 3 ++ arch/powerpc/kvm/book3s_64_mmu_radix.c | 4 +- arch/powerpc/kvm/book3s_hv_nested.c | 51 ++++++++++++++++++++++++ 4 files changed, 58 insertions(+), 2 deletions(-) diff --git a/arch/powerpc/include/asm/kvm_book3s.h b/arch/powerpc/include/asm/kvm_book3s.h index 82a0a9f3c39c..38f1b879f569 100644 --- a/arch/powerpc/include/asm/kvm_book3s.h +++ b/arch/powerpc/include/asm/kvm_book3s.h @@ -203,6 +203,8 @@ extern int kvmppc_mmu_radix_translate_table(struct kvm_vcpu *vcpu, gva_t eaddr, int table_index, u64 *pte_ret_p); extern int kvmppc_mmu_radix_xlate(struct kvm_vcpu *vcpu, gva_t eaddr, struct kvmppc_pte *gpte, bool data, bool iswrite); +extern void kvmppc_radix_tlbie_page(struct kvm *kvm, unsigned long addr, + unsigned int pshift, unsigned int lpid); extern void kvmppc_unmap_pte(struct kvm *kvm, pte_t *pte, unsigned long gpa, unsigned int shift, const struct kvm_memory_slot *memslot, diff --git a/arch/powerpc/include/asm/kvm_book3s_64.h b/arch/powerpc/include/asm/kvm_book3s_64.h index 34968fd2de24..21b1ed5df888 100644 --- a/arch/powerpc/include/asm/kvm_book3s_64.h +++ b/arch/powerpc/include/asm/kvm_book3s_64.h @@ -637,6 +637,9 @@ extern int kvmppc_create_pte(struct kvm *kvm, pgd_t *pgtable, pte_t pte, unsigned long *rmapp, struct rmap_nested **n_rmap); extern void kvmhv_insert_nest_rmap(struct kvm *kvm, unsigned long *rmapp, struct rmap_nested **n_rmap); +extern void kvmhv_update_nest_rmap_rc_list(struct kvm *kvm, unsigned long *rmapp, + unsigned long clr, unsigned long set, + unsigned long hpa, unsigned long nbytes); extern void kvmhv_remove_nest_rmap_range(struct kvm *kvm, const struct kvm_memory_slot *memslot, unsigned long gpa, unsigned long hpa, diff --git a/arch/powerpc/kvm/book3s_64_mmu_radix.c b/arch/powerpc/kvm/book3s_64_mmu_radix.c index 870ef9d5eee6..53630f0e7469 100644 --- a/arch/powerpc/kvm/book3s_64_mmu_radix.c +++ b/arch/powerpc/kvm/book3s_64_mmu_radix.c @@ -294,8 +294,8 @@ int kvmppc_mmu_radix_xlate(struct kvm_vcpu *vcpu, gva_t eaddr, return 0; } -static void kvmppc_radix_tlbie_page(struct kvm *kvm, unsigned long addr, - unsigned int pshift, unsigned int lpid) +void kvmppc_radix_tlbie_page(struct kvm *kvm, unsigned long addr, + unsigned int pshift, unsigned int lpid) { unsigned long psize = PAGE_SIZE; int psi; diff --git a/arch/powerpc/kvm/book3s_hv_nested.c b/arch/powerpc/kvm/book3s_hv_nested.c index 0bd676ac38fe..735e0ac6f5b2 100644 --- a/arch/powerpc/kvm/book3s_hv_nested.c +++ b/arch/powerpc/kvm/book3s_hv_nested.c @@ -788,6 +788,57 @@ void kvmhv_insert_nest_rmap(struct kvm *kvm, unsigned long *rmapp, *n_rmap = NULL; } +static void kvmhv_update_nest_rmap_rc(struct kvm *kvm, u64 n_rmap, + unsigned long clr, unsigned long set, + unsigned long hpa, unsigned long mask) +{ + struct kvm_nested_guest *gp; + unsigned long gpa; + unsigned int shift, lpid; + pte_t *ptep; + + gpa = n_rmap & RMAP_NESTED_GPA_MASK; + lpid = (n_rmap & RMAP_NESTED_LPID_MASK) >> RMAP_NESTED_LPID_SHIFT; + gp = kvmhv_find_nested(kvm, lpid); + if (!gp) + return; + + /* Find the pte */ + ptep = __find_linux_pte(gp->shadow_pgtable, gpa, NULL, &shift); + /* + * If the pte is present and the pfn is still the same, update the pte. + * If the pfn has changed then this is a stale rmap entry, the nested + * gpa actually points somewhere else now, and there is nothing to do. + * XXX A future optimisation would be to remove the rmap entry here. + */ + if (ptep && pte_present(*ptep) && ((pte_val(*ptep) & mask) == hpa)) { + __radix_pte_update(ptep, clr, set); + kvmppc_radix_tlbie_page(kvm, gpa, shift, lpid); + } +} + +/* + * For a given list of rmap entries, update the rc bits in all ptes in shadow + * page tables for nested guests which are referenced by the rmap list. + */ +void kvmhv_update_nest_rmap_rc_list(struct kvm *kvm, unsigned long *rmapp, + unsigned long clr, unsigned long set, + unsigned long hpa, unsigned long nbytes) +{ + struct llist_node *entry = ((struct llist_head *) rmapp)->first; + struct rmap_nested *cursor; + unsigned long rmap, mask; + + if ((clr | set) & ~(_PAGE_DIRTY | _PAGE_ACCESSED)) + return; + + mask = PTE_RPN_MASK & ~(nbytes - 1); + hpa &= mask; + + for_each_nest_rmap_safe(cursor, entry, &rmap) + kvmhv_update_nest_rmap_rc(kvm, rmap, clr, set, hpa, mask); +} + static void kvmhv_remove_nest_rmap(struct kvm *kvm, u64 n_rmap, unsigned long hpa, unsigned long mask) { -- 2.45.2