From dc891849e030199d203334b2ddd2bd4fc5a87733 Mon Sep 17 00:00:00 2001 From: "Aneesh Kumar K.V" Date: Tue, 5 May 2020 12:47:17 +0530 Subject: powerpc/kvm/nested: Add helper to walk nested shadow linux page table. The locking rules for walking nested shadow linux page table is different from process scoped table. Hence add a helper for nested page table walk and also add check whether we are holding the right locks. Signed-off-by: Aneesh Kumar K.V Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200505071729.54912-11-aneesh.kumar@linux.ibm.com --- arch/powerpc/kvm/book3s_hv_nested.c | 28 +++++++++++++++++++++------- 1 file changed, 21 insertions(+), 7 deletions(-) (limited to 'arch/powerpc/kvm') diff --git a/arch/powerpc/kvm/book3s_hv_nested.c b/arch/powerpc/kvm/book3s_hv_nested.c index 7f1fc5db13ea..b2cc3eaec618 100644 --- a/arch/powerpc/kvm/book3s_hv_nested.c +++ b/arch/powerpc/kvm/book3s_hv_nested.c @@ -750,6 +750,24 @@ static struct kvm_nested_guest *kvmhv_find_nested(struct kvm *kvm, int lpid) return kvm->arch.nested_guests[lpid]; } +static pte_t *find_kvm_nested_guest_pte(struct kvm *kvm, unsigned long lpid, + unsigned long ea, unsigned *hshift) +{ + struct kvm_nested_guest *gp; + pte_t *pte; + + gp = kvmhv_find_nested(kvm, lpid); + if (!gp) + return NULL; + + VM_WARN(!spin_is_locked(&kvm->mmu_lock), + "%s called with kvm mmu_lock not held \n", __func__); + pte = __find_linux_pte(gp->shadow_pgtable, ea, NULL, hshift); + + return pte; +} + + static inline bool kvmhv_n_rmap_is_equal(u64 rmap_1, u64 rmap_2) { return !((rmap_1 ^ rmap_2) & (RMAP_NESTED_LPID_MASK | @@ -792,19 +810,15 @@ 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); + ptep = find_kvm_nested_guest_pte(kvm, lpid, gpa, &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 @@ -854,7 +868,7 @@ static void kvmhv_remove_nest_rmap(struct kvm *kvm, u64 n_rmap, return; /* Find and invalidate the pte */ - ptep = __find_linux_pte(gp->shadow_pgtable, gpa, NULL, &shift); + ptep = find_kvm_nested_guest_pte(kvm, lpid, gpa, &shift); /* Don't spuriously invalidate ptes if the pfn has changed */ if (ptep && pte_present(*ptep) && ((pte_val(*ptep) & mask) == hpa)) kvmppc_unmap_pte(kvm, ptep, gpa, shift, NULL, gp->shadow_lpid); @@ -921,7 +935,7 @@ static bool kvmhv_invalidate_shadow_pte(struct kvm_vcpu *vcpu, int shift; spin_lock(&kvm->mmu_lock); - ptep = __find_linux_pte(gp->shadow_pgtable, gpa, NULL, &shift); + ptep = find_kvm_nested_guest_pte(kvm, gp->l1_lpid, gpa, &shift); if (!shift) shift = PAGE_SHIFT; if (ptep && pte_present(*ptep)) { -- cgit v1.2.3