// SPDX-License-Identifier: GPL-2.0 /* * Copyright IBM Corporation, 2018 * Authors Suraj Jitindar Singh * Paul Mackerras * * Description: KVM functions specific to running nested KVM-HV guests * on Book3S processors (specifically POWER9 and later). */ #include #include #include #include #include #include #include #include #include #include static struct patb_entry *pseries_partition_tb; static void kvmhv_update_ptbl_cache(struct kvm_nested_guest *gp); static void kvmhv_free_memslot_nest_rmap(struct kvm_memory_slot *free); void kvmhv_save_hv_regs(struct kvm_vcpu *vcpu, struct hv_guest_state *hr) { struct kvmppc_vcore *vc = vcpu->arch.vcore; hr->pcr = vc->pcr; hr->dpdes = vc->dpdes; hr->hfscr = vcpu->arch.hfscr; hr->tb_offset = vc->tb_offset; hr->dawr0 = vcpu->arch.dawr; hr->dawrx0 = vcpu->arch.dawrx; hr->ciabr = vcpu->arch.ciabr; hr->purr = vcpu->arch.purr; hr->spurr = vcpu->arch.spurr; hr->ic = vcpu->arch.ic; hr->vtb = vc->vtb; hr->srr0 = vcpu->arch.shregs.srr0; hr->srr1 = vcpu->arch.shregs.srr1; hr->sprg[0] = vcpu->arch.shregs.sprg0; hr->sprg[1] = vcpu->arch.shregs.sprg1; hr->sprg[2] = vcpu->arch.shregs.sprg2; hr->sprg[3] = vcpu->arch.shregs.sprg3; hr->pidr = vcpu->arch.pid; hr->cfar = vcpu->arch.cfar; hr->ppr = vcpu->arch.ppr; } static void byteswap_pt_regs(struct pt_regs *regs) { unsigned long *addr = (unsigned long *) regs; for (; addr < ((unsigned long *) (regs + 1)); addr++) *addr = swab64(*addr); } static void byteswap_hv_regs(struct hv_guest_state *hr) { hr->version = swab64(hr->version); hr->lpid = swab32(hr->lpid); hr->vcpu_token = swab32(hr->vcpu_token); hr->lpcr = swab64(hr->lpcr); hr->pcr = swab64(hr->pcr); hr->amor = swab64(hr->amor); hr->dpdes = swab64(hr->dpdes); hr->hfscr = swab64(hr->hfscr); hr->tb_offset = swab64(hr->tb_offset); hr->dawr0 = swab64(hr->dawr0); hr->dawrx0 = swab64(hr->dawrx0); hr->ciabr = swab64(hr->ciabr); hr->hdec_expiry = swab64(hr->hdec_expiry); hr->purr = swab64(hr->purr); hr->spurr = swab64(hr->spurr); hr->ic = swab64(hr->ic); hr->vtb = swab64(hr->vtb); hr->hdar = swab64(hr->hdar); hr->hdsisr = swab64(hr->hdsisr); hr->heir = swab64(hr->heir); hr->asdr = swab64(hr->asdr); hr->srr0 = swab64(hr->srr0); hr->srr1 = swab64(hr->srr1); hr->sprg[0] = swab64(hr->sprg[0]); hr->sprg[1] = swab64(hr->sprg[1]); hr->sprg[2] = swab64(hr->sprg[2]); hr->sprg[3] = swab64(hr->sprg[3]); hr->pidr = swab64(hr->pidr); hr->cfar = swab64(hr->cfar); hr->ppr = swab64(hr->ppr); } static void save_hv_return_state(struct kvm_vcpu *vcpu, int trap, struct hv_guest_state *hr) { struct kvmppc_vcore *vc = vcpu->arch.vcore; hr->dpdes = vc->dpdes; hr->hfscr = vcpu->arch.hfscr; hr->purr = vcpu->arch.purr; hr->spurr = vcpu->arch.spurr; hr->ic = vcpu->arch.ic; hr->vtb = vc->vtb; hr->srr0 = vcpu->arch.shregs.srr0; hr->srr1 = vcpu->arch.shregs.srr1; hr->sprg[0] = vcpu->arch.shregs.sprg0; hr->sprg[1] = vcpu->arch.shregs.sprg1; hr->sprg[2] = vcpu->arch.shregs.sprg2; hr->sprg[3] = vcpu->arch.shregs.sprg3; hr->pidr = vcpu->arch.pid; hr->cfar = vcpu->arch.cfar; hr->ppr = vcpu->arch.ppr; switch (trap) { case BOOK3S_INTERRUPT_H_DATA_STORAGE: hr->hdar = vcpu->arch.fault_dar; hr->hdsisr = vcpu->arch.fault_dsisr; hr->asdr = vcpu->arch.fault_gpa; break; case BOOK3S_INTERRUPT_H_INST_STORAGE: hr->asdr = vcpu->arch.fault_gpa; break; case BOOK3S_INTERRUPT_H_EMUL_ASSIST: hr->heir = vcpu->arch.emul_inst; break; } } static void sanitise_hv_regs(struct kvm_vcpu *vcpu, struct hv_guest_state *hr) { /* * Don't let L1 enable features for L2 which we've disabled for L1, * but preserve the interrupt cause field. */ hr->hfscr &= (HFSCR_INTR_CAUSE | vcpu->arch.hfscr); /* Don't let data address watchpoint match in hypervisor state */ hr->dawrx0 &= ~DAWRX_HYP; /* Don't let completed instruction address breakpt match in HV state */ if ((hr->ciabr & CIABR_PRIV) == CIABR_PRIV_HYPER) hr->ciabr &= ~CIABR_PRIV; } static void restore_hv_regs(struct kvm_vcpu *vcpu, struct hv_guest_state *hr) { struct kvmppc_vcore *vc = vcpu->arch.vcore; vc->pcr = hr->pcr; vc->dpdes = hr->dpdes; vcpu->arch.hfscr = hr->hfscr; vcpu->arch.dawr = hr->dawr0; vcpu->arch.dawrx = hr->dawrx0; vcpu->arch.ciabr = hr->ciabr; vcpu->arch.purr = hr->purr; vcpu->arch.spurr = hr->spurr; vcpu->arch.ic = hr->ic; vc->vtb = hr->vtb; vcpu->arch.shregs.srr0 = hr->srr0; vcpu->arch.shregs.srr1 = hr->srr1; vcpu->arch.shregs.sprg0 = hr->sprg[0]; vcpu->arch.shregs.sprg1 = hr->sprg[1]; vcpu->arch.shregs.sprg2 = hr->sprg[2]; vcpu->arch.shregs.sprg3 = hr->sprg[3]; vcpu->arch.pid = hr->pidr; vcpu->arch.cfar = hr->cfar; vcpu->arch.ppr = hr->ppr; } void kvmhv_restore_hv_return_state(struct kvm_vcpu *vcpu, struct hv_guest_state *hr) { struct kvmppc_vcore *vc = vcpu->arch.vcore; vc->dpdes = hr->dpdes; vcpu->arch.hfscr = hr->hfscr; vcpu->arch.purr = hr->purr; vcpu->arch.spurr = hr->spurr; vcpu->arch.ic = hr->ic; vc->vtb = hr->vtb; vcpu->arch.fault_dar = hr->hdar; vcpu->arch.fault_dsisr = hr->hdsisr; vcpu->arch.fault_gpa = hr->asdr; vcpu->arch.emul_inst = hr->heir; vcpu->arch.shregs.srr0 = hr->srr0; vcpu->arch.shregs.srr1 = hr->srr1; vcpu->arch.shregs.sprg0 = hr->sprg[0]; vcpu->arch.shregs.sprg1 = hr->sprg[1]; vcpu->arch.shregs.sprg2 = hr->sprg[2]; vcpu->arch.shregs.sprg3 = hr->sprg[3]; vcpu->arch.pid = hr->pidr; vcpu->arch.cfar = hr->cfar; vcpu->arch.ppr = hr->ppr; } long kvmhv_enter_nested_guest(struct kvm_vcpu *vcpu) { long int err, r; struct kvm_nested_guest *l2; struct pt_regs l2_regs, saved_l1_regs; struct hv_guest_state l2_hv, saved_l1_hv; struct kvmppc_vcore *vc = vcpu->arch.vcore; u64 hv_ptr, regs_ptr; u64 hdec_exp; s64 delta_purr, delta_spurr, delta_ic, delta_vtb; u64 mask; unsigned long lpcr; if (vcpu->kvm->arch.l1_ptcr == 0) return H_NOT_AVAILABLE; /* copy parameters in */ hv_ptr = kvmppc_get_gpr(vcpu, 4); err = kvm_vcpu_read_guest(vcpu, hv_ptr, &l2_hv, sizeof(struct hv_guest_state)); if (err) return H_PARAMETER; if (kvmppc_need_byteswap(vcpu)) byteswap_hv_regs(&l2_hv); if (l2_hv.version != HV_GUEST_STATE_VERSION) return H_P2; regs_ptr = kvmppc_get_gpr(vcpu, 5); err = kvm_vcpu_read_guest(vcpu, regs_ptr, &l2_regs, sizeof(struct pt_regs)); if (err) return H_PARAMETER; if (kvmppc_need_byteswap(vcpu)) byteswap_pt_regs(&l2_regs); if (l2_hv.vcpu_token >= NR_CPUS) return H_PARAMETER; /* translate lpid */ l2 = kvmhv_get_nested(vcpu->kvm, l2_hv.lpid, true); if (!l2) return H_PARAMETER; if (!l2->l1_gr_to_hr) { mutex_lock(&l2->tlb_lock); kvmhv_update_ptbl_cache(l2); mutex_unlock(&l2->tlb_lock); } /* save l1 values of things */ vcpu->arch.regs.msr = vcpu->arch.shregs.msr; saved_l1_regs = vcpu->arch.regs; kvmhv_save_hv_regs(vcpu, &saved_l1_hv); /* convert TB values/offsets to host (L0) values */ hdec_exp = l2_hv.hdec_expiry - vc->tb_offset; vc->tb_offset += l2_hv.tb_offset; /* set L1 state to L2 state */ vcpu->arch.nested = l2; vcpu->arch.nested_vcpu_id = l2_hv.vcpu_token; vcpu->arch.regs = l2_regs; vcpu->arch.shregs.msr = vcpu->arch.regs.msr; mask = LPCR_DPFD | LPCR_ILE | LPCR_TC | LPCR_AIL | LPCR_LD | LPCR_LPES | LPCR_MER; lpcr = (vc->lpcr & ~mask) | (l2_hv.lpcr & mask); sanitise_hv_regs(vcpu, &l2_hv); restore_hv_regs(vcpu, &l2_hv); vcpu->arch.ret = RESUME_GUEST; vcpu->arch.trap = 0; do { if (mftb() >= hdec_exp) { vcpu->arch.trap = BOOK3S_INTERRUPT_HV_DECREMENTER; r = RESUME_HOST; break; } r = kvmhv_run_single_vcpu(vcpu->arch.kvm_run, vcpu, hdec_exp, lpcr); } while (is_kvmppc_resume_guest(r)); /* save L2 state for return */ l2_regs = vcpu->arch.regs; l2_regs.msr = vcpu->arch.shregs.msr; delta_purr = vcpu->arch.purr - l2_hv.purr; delta_spurr = vcpu->arch.spurr - l2_hv.spurr; delta_ic = vcpu->arch.ic - l2_hv.ic; delta_vtb = vc->vtb - l2_hv.vtb; save_hv_return_state(vcpu, vcpu->arch.trap, &l2_hv); /* restore L1 state */ vcpu->arch.nested = NULL; vcpu->arch.regs = saved_l1_regs; vcpu->arch.shregs.msr = saved_l1_regs.msr & ~MSR_TS_MASK; /* set L1 MSR TS field according to L2 transaction state */ if (l2_regs.msr & MSR_TS_MASK) vcpu->arch.shregs.msr |= MSR_TS_S; vc->tb_offset = saved_l1_hv.tb_offset; restore_hv_regs(vcpu, &saved_l1_hv); vcpu->arch.purr += delta_purr; vcpu->arch.spurr += delta_spurr; vcpu->arch.ic += delta_ic; vc->vtb += delta_vtb; kvmhv_put_nested(l2); /* copy l2_hv_state and regs back to guest */ if (kvmppc_need_byteswap(vcpu)) { byteswap_hv_regs(&l2_hv); byteswap_pt_regs(&l2_regs); } err = kvm_vcpu_write_guest(vcpu, hv_ptr, &l2_hv, sizeof(struct hv_guest_state)); if (err) return H_AUTHORITY; err = kvm_vcpu_write_guest(vcpu, regs_ptr, &l2_regs, sizeof(struct pt_regs)); if (err) return H_AUTHORITY; if (r == -EINTR) return H_INTERRUPT; return vcpu->arch.trap; } long kvmhv_nested_init(void) { long int ptb_order; unsigned long ptcr; long rc; if (!kvmhv_on_pseries()) return 0; if (!radix_enabled()) return -ENODEV; /* find log base 2 of KVMPPC_NR_LPIDS, rounding up */ ptb_order = __ilog2(KVMPPC_NR_LPIDS - 1) + 1; if (ptb_order < 8) ptb_order = 8; pseries_partition_tb = kmalloc(sizeof(struct patb_entry) << ptb_order, GFP_KERNEL); if (!pseries_partition_tb) { pr_err("kvm-hv: failed to allocated nested partition table\n"); return -ENOMEM; } ptcr = __pa(pseries_partition_tb) | (ptb_order - 8); rc = plpar_hcall_norets(H_SET_PARTITION_TABLE, ptcr); if (rc != H_SUCCESS) { pr_err("kvm-hv: Parent hypervisor does not support nesting (rc=%ld)\n", rc); kfree(pseries_partition_tb); pseries_partition_tb = NULL; return -ENODEV; } return 0; } void kvmhv_nested_exit(void) { /* * N.B. the kvmhv_on_pseries() test is there because it enables * the compiler to remove the call to plpar_hcall_norets() * when CONFIG_PPC_PSERIES=n. */ if (kvmhv_on_pseries() && pseries_partition_tb) { plpar_hcall_norets(H_SET_PARTITION_TABLE, 0); kfree(pseries_partition_tb); pseries_partition_tb = NULL; } } static void kvmhv_flush_lpid(unsigned int lpid) { long rc; if (!kvmhv_on_pseries()) { radix__flush_tlb_lpid(lpid); return; } rc = plpar_hcall_norets(H_TLB_INVALIDATE, H_TLBIE_P1_ENC(2, 0, 1), lpid, TLBIEL_INVAL_SET_LPID); if (rc) pr_err("KVM: TLB LPID invalidation hcall failed, rc=%ld\n", rc); } void kvmhv_set_ptbl_entry(unsigned int lpid, u64 dw0, u64 dw1) { if (!kvmhv_on_pseries()) { mmu_partition_table_set_entry(lpid, dw0, dw1); return; } pseries_partition_tb[lpid].patb0 = cpu_to_be64(dw0); pseries_partition_tb[lpid].patb1 = cpu_to_be64(dw1); /* L0 will do the necessary barriers */ kvmhv_flush_lpid(lpid); } static void kvmhv_set_nested_ptbl(struct kvm_nested_guest *gp) { unsigned long dw0; dw0 = PATB_HR | radix__get_tree_size() | __pa(gp->shadow_pgtable) | RADIX_PGD_INDEX_SIZE; kvmhv_set_ptbl_entry(gp->shadow_lpid, dw0, gp->process_table); } void kvmhv_vm_nested_init(struct kvm *kvm) { kvm->arch.max_nested_lpid = -1; } /* * Handle the H_SET_PARTITION_TABLE hcall. * r4 = guest real address of partition table + log_2(size) - 12 * (formatted as for the PTCR). */ long kvmhv_set_partition_table(struct kvm_vcpu *vcpu) { struct kvm *kvm = vcpu->kvm; unsigned long ptcr = kvmppc_get_gpr(vcpu, 4); int srcu_idx; long ret = H_SUCCESS; srcu_idx = srcu_read_lock(&kvm->srcu); /* * Limit the partition table to 4096 entries (because that's what * hardware supports), and check the base address. */ if ((ptcr & PRTS_MASK) > 12 - 8 || !kvm_is_visible_gfn(vcpu->kvm, (ptcr & PRTB_MASK) >> PAGE_SHIFT)) ret = H_PARAMETER; srcu_read_unlock(&kvm->srcu, srcu_idx); if (ret == H_SUCCESS) kvm->arch.l1_ptcr = ptcr; return ret; } /* * Reload the partition table entry for a guest. * Caller must hold gp->tlb_lock. */ static void kvmhv_update_ptbl_cache(struct kvm_nested_guest *gp) { int ret; struct patb_entry ptbl_entry; unsigned long ptbl_addr; struct kvm *kvm = gp->l1_host; ret = -EFAULT; ptbl_addr = (kvm->arch.l1_ptcr & PRTB_MASK) + (gp->l1_lpid << 4); if (gp->l1_lpid < (1ul << ((kvm->arch.l1_ptcr & PRTS_MASK) + 8))) ret = kvm_read_guest(kvm, ptbl_addr, &ptbl_entry, sizeof(ptbl_entry)); if (ret) { gp->l1_gr_to_hr = 0; gp->process_table = 0; } else { gp->l1_gr_to_hr = be64_to_cpu(ptbl_entry.patb0); gp->process_table = be64_to_cpu(ptbl_entry.patb1); } kvmhv_set_nested_ptbl(gp); } struct kvm_nested_guest *kvmhv_alloc_nested(struct kvm *kvm, unsigned int lpid) { struct kvm_nested_guest *gp; long shadow_lpid; gp = kzalloc(sizeof(*gp), GFP_KERNEL); if (!gp) return NULL; gp->l1_host = kvm; gp->l1_lpid = lpid; mutex_init(&gp->tlb_lock); gp->shadow_pgtable = pgd_alloc(kvm->mm); if (!gp->shadow_pgtable) goto out_free; shadow_lpid = kvmppc_alloc_lpid(); if (shadow_lpid < 0) goto out_free2; gp->shadow_lpid = shadow_lpid; gp->radix = 1; memset(gp->prev_cpu, -1, sizeof(gp->prev_cpu)); return gp; out_free2: pgd_free(kvm->mm, gp->shadow_pgtable); out_free: kfree(gp); return NULL; } /* * Free up any resources allocated for a nested guest. */ static void kvmhv_release_nested(struct kvm_nested_guest *gp) { struct kvm *kvm = gp->l1_host; if (gp->shadow_pgtable) { /* * No vcpu is using this struct and no call to * kvmhv_get_nested can find this struct, * so we don't need to hold kvm->mmu_lock. */ kvmppc_free_pgtable_radix(kvm, gp->shadow_pgtable, gp->shadow_lpid); pgd_free(kvm->mm, gp->shadow_pgtable); } kvmhv_set_ptbl_entry(gp->shadow_lpid, 0, 0); kvmppc_free_lpid(gp->shadow_lpid); kfree(gp); } static void kvmhv_remove_nested(struct kvm_nested_guest *gp) { struct kvm *kvm = gp->l1_host; int lpid = gp->l1_lpid; long ref; spin_lock(&kvm->mmu_lock); if (gp == kvm->arch.nested_guests[lpid]) { kvm->arch.nested_guests[lpid] = NULL; if (lpid == kvm->arch.max_nested_lpid) { while (--lpid >= 0 && !kvm->arch.nested_guests[lpid]) ; kvm->arch.max_nested_lpid = lpid; } --gp->refcnt; } ref = gp->refcnt; spin_unlock(&kvm->mmu_lock); if (ref == 0) kvmhv_release_nested(gp); } /* * Free up all nested resources allocated for this guest. * This is called with no vcpus of the guest running, when * switching the guest to HPT mode or when destroying the * guest. */ void kvmhv_release_all_nested(struct kvm *kvm) { int i; struct kvm_nested_guest *gp; struct kvm_nested_guest *freelist = NULL; struct kvm_memory_slot *memslot; int srcu_idx; spin_lock(&kvm->mmu_lock); for (i = 0; i <= kvm->arch.max_nested_lpid; i++) { gp = kvm->arch.nested_guests[i]; if (!gp) continue; kvm->arch.nested_guests[i] = NULL; if (--gp->refcnt == 0) { gp->next = freelist; freelist = gp; } } kvm->arch.max_nested_lpid = -1; spin_unlock(&kvm->mmu_lock); while ((gp = freelist) != NULL) { freelist = gp->next; kvmhv_release_nested(gp); } srcu_idx = srcu_read_lock(&kvm->srcu); kvm_for_each_memslot(memslot, kvm_memslots(kvm)) kvmhv_free_memslot_nest_rmap(memslot); srcu_read_unlock(&kvm->srcu, srcu_idx); } /* caller must hold gp->tlb_lock */ static void kvmhv_flush_nested(struct kvm_nested_guest *gp) { struct kvm *kvm = gp->l1_host; spin_lock(&kvm->mmu_lock); kvmppc_free_pgtable_radix(kvm, gp->shadow_pgtable, gp->shadow_lpid); spin_unlock(&kvm->mmu_lock); kvmhv_flush_lpid(gp->shadow_lpid); kvmhv_update_ptbl_cache(gp); if (gp->l1_gr_to_hr == 0) kvmhv_remove_nested(gp); } struct kvm_nested_guest *kvmhv_get_nested(struct kvm *kvm, int l1_lpid, bool create) { struct kvm_nested_guest *gp, *newgp; if (l1_lpid >= KVM_MAX_NESTED_GUESTS || l1_lpid >= (1ul << ((kvm->arch.l1_ptcr & PRTS_MASK) + 12 - 4))) return NULL; spin_lock(&kvm->mmu_lock); gp = kvm->arch.nested_guests[l1_lpid]; if (gp) ++gp->refcnt; spin_unlock(&kvm->mmu_lock); if (gp || !create) return gp; newgp = kvmhv_alloc_nested(kvm, l1_lpid); if (!newgp) return NULL; spin_lock(&kvm->mmu_lock); if (kvm->arch.nested_guests[l1_lpid]) { /* someone else beat us to it */ gp = kvm->arch.nested_guests[l1_lpid]; } else { kvm->arch.nested_guests[l1_lpid] = newgp; ++newgp->refcnt; gp = newgp; newgp = NULL; if (l1_lpid > kvm->arch.max_nested_lpid) kvm->arch.max_nested_lpid = l1_lpid; } ++gp->refcnt; spin_unlock(&kvm->mmu_lock); if (newgp) kvmhv_release_nested(newgp); return gp; } void kvmhv_put_nested(struct kvm_nested_guest *gp) { struct kvm *kvm = gp->l1_host; long ref; spin_lock(&kvm->mmu_lock); ref = --gp->refcnt; spin_unlock(&kvm->mmu_lock); if (ref == 0) kvmhv_release_nested(gp); } static struct kvm_nested_guest *kvmhv_find_nested(struct kvm *kvm, int lpid) { if (lpid > kvm->arch.max_nested_lpid) return NULL; return kvm->arch.nested_guests[lpid]; } static inline bool kvmhv_n_rmap_is_equal(u64 rmap_1, u64 rmap_2) { return !((rmap_1 ^ rmap_2) & (RMAP_NESTED_LPID_MASK | RMAP_NESTED_GPA_MASK)); } void kvmhv_insert_nest_rmap(struct kvm *kvm, unsigned long *rmapp, struct rmap_nested **n_rmap) { struct llist_node *entry = ((struct llist_head *) rmapp)->first; struct rmap_nested *cursor; u64 rmap, new_rmap = (*n_rmap)->rmap; /* Are there any existing entries? */ if (!(*rmapp)) { /* No -> use the rmap as a single entry */ *rmapp = new_rmap | RMAP_NESTED_IS_SINGLE_ENTRY; return; } /* Do any entries match what we're trying to insert? */ for_each_nest_rmap_safe(cursor, entry, &rmap) { if (kvmhv_n_rmap_is_equal(rmap, new_rmap)) return; } /* Do we need to create a list or just add the new entry? */ rmap = *rmapp; if (rmap & RMAP_NESTED_IS_SINGLE_ENTRY) /* Not previously a list */ *rmapp = 0UL; llist_add(&((*n_rmap)->list), (struct llist_head *) rmapp); if (rmap & RMAP_NESTED_IS_SINGLE_ENTRY) /* Not previously a list */ (*n_rmap)->list.next = (struct llist_node *) rmap; /* Set NULL so not freed by caller */ *n_rmap = NULL; } static void kvmhv_remove_nest_rmap(struct kvm *kvm, u64 n_rmap, 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 and invalidate the pte */ ptep = __find_linux_pte(gp->shadow_pgtable, gpa, NULL, &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); } static void kvmhv_remove_nest_rmap_list(struct kvm *kvm, unsigned long *rmapp, unsigned long hpa, unsigned long mask) { struct llist_node *entry = llist_del_all((struct llist_head *) rmapp); struct rmap_nested *cursor; unsigned long rmap; for_each_nest_rmap_safe(cursor, entry, &rmap) { kvmhv_remove_nest_rmap(kvm, rmap, hpa, mask); kfree(cursor); } } /* called with kvm->mmu_lock held */ void kvmhv_remove_nest_rmap_range(struct kvm *kvm, const struct kvm_memory_slot *memslot, unsigned long gpa, unsigned long hpa, unsigned long nbytes) { unsigned long gfn, end_gfn; unsigned long addr_mask; if (!memslot) return; gfn = (gpa >> PAGE_SHIFT) - memslot->base_gfn; end_gfn = gfn + (nbytes >> PAGE_SHIFT); addr_mask = PTE_RPN_MASK & ~(nbytes - 1); hpa &= addr_mask; for (; gfn < end_gfn; gfn++) { unsigned long *rmap = &memslot->arch.rmap[gfn]; kvmhv_remove_nest_rmap_list(kvm, rmap, hpa, addr_mask); } } static void kvmhv_free_memslot_nest_rmap(struct kvm_memory_slot *free) { unsigned long page; for (page = 0; page < free->npages; page++) { unsigned long rmap, *rmapp = &free->arch.rmap[page]; struct rmap_nested *cursor; struct llist_node *entry; entry = llist_del_all((struct llist_head *) rmapp); for_each_nest_rmap_safe(cursor, entry, &rmap) kfree(cursor); } } static bool kvmhv_invalidate_shadow_pte(struct kvm_vcpu *vcpu, struct kvm_nested_guest *gp, long gpa, int *shift_ret) { struct kvm *kvm = vcpu->kvm; bool ret = false; pte_t *ptep; int shift; spin_lock(&kvm->mmu_lock); ptep = __find_linux_pte(gp->shadow_pgtable, gpa, NULL, &shift); if (!shift) shift = PAGE_SHIFT; if (ptep && pte_present(*ptep)) { kvmppc_unmap_pte(kvm, ptep, gpa, shift, NULL, gp->shadow_lpid); ret = true; } spin_unlock(&kvm->mmu_lock); if (shift_ret) *shift_ret = shift; return ret; } static inline int get_ric(unsigned int instr) { return (instr >> 18) & 0x3; } static inline int get_prs(unsigned int instr) { return (instr >> 17) & 0x1; } static inline int get_r(unsigned int instr) { return (instr >> 16) & 0x1; } static inline int get_lpid(unsigned long r_val) { return r_val & 0xffffffff; } static inline int get_is(unsigned long r_val) { return (r_val >> 10) & 0x3; } static inline int get_ap(unsigned long r_val) { return (r_val >> 5) & 0x7; } static inline long get_epn(unsigned long r_val) { return r_val >> 12; } static int kvmhv_emulate_tlbie_tlb_addr(struct kvm_vcpu *vcpu, int lpid, int ap, long epn) { struct kvm *kvm = vcpu->kvm; struct kvm_nested_guest *gp; long npages; int shift, shadow_shift; unsigned long addr; shift = ap_to_shift(ap); addr = epn << 12; if (shift < 0) /* Invalid ap encoding */ return -EINVAL; addr &= ~((1UL << shift) - 1); npages = 1UL << (shift - PAGE_SHIFT); gp = kvmhv_get_nested(kvm, lpid, false); if (!gp) /* No such guest -> nothing to do */ return 0; mutex_lock(&gp->tlb_lock); /* There may be more than one host page backing this single guest pte */ do { kvmhv_invalidate_shadow_pte(vcpu, gp, addr, &shadow_shift); npages -= 1UL << (shadow_shift - PAGE_SHIFT); addr += 1UL << shadow_shift; } while (npages > 0); mutex_unlock(&gp->tlb_lock); kvmhv_put_nested(gp); return 0; } static void kvmhv_emulate_tlbie_lpid(struct kvm_vcpu *vcpu, struct kvm_nested_guest *gp, int ric) { struct kvm *kvm = vcpu->kvm; mutex_lock(&gp->tlb_lock); switch (ric) { case 0: /* Invalidate TLB */ spin_lock(&kvm->mmu_lock); kvmppc_free_pgtable_radix(kvm, gp->shadow_pgtable, gp->shadow_lpid); kvmhv_flush_lpid(gp->shadow_lpid); spin_unlock(&kvm->mmu_lock); break; case 1: /* * Invalidate PWC * We don't cache this -> nothing to do */ break; case 2: /* Invalidate TLB, PWC and caching of partition table entries */ kvmhv_flush_nested(gp); break; default: break; } mutex_unlock(&gp->tlb_lock); } static void kvmhv_emulate_tlbie_all_lpid(struct kvm_vcpu *vcpu, int ric) { struct kvm *kvm = vcpu->kvm; struct kvm_nested_guest *gp; int i; spin_lock(&kvm->mmu_lock); for (i = 0; i <= kvm->arch.max_nested_lpid; i++) { gp = kvm->arch.nested_guests[i]; if (gp) { spin_unlock(&kvm->mmu_lock); kvmhv_emulate_tlbie_lpid(vcpu, gp, ric); spin_lock(&kvm->mmu_lock); } } spin_unlock(&kvm->mmu_lock); } static int kvmhv_emulate_priv_tlbie(struct kvm_vcpu *vcpu, unsigned int instr, unsigned long rsval, unsigned long rbval) { struct kvm *kvm = vcpu->kvm; struct kvm_nested_guest *gp; int r, ric, prs, is, ap; int lpid; long epn; int ret = 0; ric = get_ric(instr); prs = get_prs(instr); r = get_r(instr); lpid = get_lpid(rsval); is = get_is(rbval); /* * These cases are invalid and are not handled: * r != 1 -> Only radix supported * prs == 1 -> Not HV privileged * ric == 3 -> No cluster bombs for radix * is == 1 -> Partition scoped translations not associated with pid * (!is) && (ric == 1 || ric == 2) -> Not supported by ISA */ if ((!r) || (prs) || (ric == 3) || (is == 1) || ((!is) && (ric == 1 || ric == 2))) return -EINVAL; switch (is) { case 0: /* * We know ric == 0 * Invalidate TLB for a given target address */ epn = get_epn(rbval); ap = get_ap(rbval); ret = kvmhv_emulate_tlbie_tlb_addr(vcpu, lpid, ap, epn); break; case 2: /* Invalidate matching LPID */ gp = kvmhv_get_nested(kvm, lpid, false); if (gp) { kvmhv_emulate_tlbie_lpid(vcpu, gp, ric); kvmhv_put_nested(gp); } break; case 3: /* Invalidate ALL LPIDs */ kvmhv_emulate_tlbie_all_lpid(vcpu, ric); break; default: ret = -EINVAL; break; } return ret; } /* * This handles the H_TLB_INVALIDATE hcall. * Parameters are (r4) tlbie instruction code, (r5) rS contents, * (r6) rB contents. */ long kvmhv_do_nested_tlbie(struct kvm_vcpu *vcpu) { int ret; ret = kvmhv_emulate_priv_tlbie(vcpu, kvmppc_get_gpr(vcpu, 4), kvmppc_get_gpr(vcpu, 5), kvmppc_get_gpr(vcpu, 6)); if (ret) return H_PARAMETER; return H_SUCCESS; } /* Used to convert a nested guest real address to a L1 guest real address */ static int kvmhv_translate_addr_nested(struct kvm_vcpu *vcpu, struct kvm_nested_guest *gp, unsigned long n_gpa, unsigned long dsisr, struct kvmppc_pte *gpte_p) { u64 fault_addr, flags = dsisr & DSISR_ISSTORE; int ret; ret = kvmppc_mmu_walk_radix_tree(vcpu, n_gpa, gpte_p, gp->l1_gr_to_hr, &fault_addr); if (ret) { /* We didn't find a pte */ if (ret == -EINVAL) { /* Unsupported mmu config */ flags |= DSISR_UNSUPP_MMU; } else if (ret == -ENOENT) { /* No translation found */ flags |= DSISR_NOHPTE; } else if (ret == -EFAULT) { /* Couldn't access L1 real address */ flags |= DSISR_PRTABLE_FAULT; vcpu->arch.fault_gpa = fault_addr; } else { /* Unknown error */ return ret; } goto forward_to_l1; } else { /* We found a pte -> check permissions */ if (dsisr & DSISR_ISSTORE) { /* Can we write? */ if (!gpte_p->may_write) { flags |= DSISR_PROTFAULT; goto forward_to_l1; } } else if (vcpu->arch.trap == BOOK3S_INTERRUPT_H_INST_STORAGE) { /* Can we execute? */ if (!gpte_p->may_execute) { flags |= SRR1_ISI_N_OR_G; goto forward_to_l1; } } else { /* Can we read? */ if (!gpte_p->may_read && !gpte_p->may_write) { flags |= DSISR_PROTFAULT; goto forward_to_l1; } } } return 0; forward_to_l1: vcpu->arch.fault_dsisr = flags; if (vcpu->arch.trap == BOOK3S_INTERRUPT_H_INST_STORAGE) { vcpu->arch.shregs.msr &= ~0x783f0000ul; vcpu->arch.shregs.msr |= flags; } return RESUME_HOST; } static long kvmhv_handle_nested_set_rc(struct kvm_vcpu *vcpu, struct kvm_nested_guest *gp, unsigned long n_gpa, struct kvmppc_pte gpte, unsigned long dsisr) { struct kvm *kvm = vcpu->kvm; bool writing = !!(dsisr & DSISR_ISSTORE); u64 pgflags; bool ret; /* Are the rc bits set in the L1 partition scoped pte? */ pgflags = _PAGE_ACCESSED; if (writing) pgflags |= _PAGE_DIRTY; if (pgflags & ~gpte.rc) return RESUME_HOST; spin_lock(&kvm->mmu_lock); /* Set the rc bit in the pte of our (L0) pgtable for the L1 guest */ ret = kvmppc_hv_handle_set_rc(kvm, kvm->arch.pgtable, writing, gpte.raddr, kvm->arch.lpid); spin_unlock(&kvm->mmu_lock); if (!ret) return -EINVAL; /* Set the rc bit in the pte of the shadow_pgtable for the nest guest */ ret = kvmppc_hv_handle_set_rc(kvm, gp->shadow_pgtable, writing, n_gpa, gp->shadow_lpid); if (!ret) return -EINVAL; return 0; } static inline int kvmppc_radix_level_to_shift(int level) { switch (level) { case 2: return PUD_SHIFT; case 1: return PMD_SHIFT; default: return PAGE_SHIFT; } } static inline int kvmppc_radix_shift_to_level(int shift) { if (shift == PUD_SHIFT) return 2; if (shift == PMD_SHIFT) return 1; if (shift == PAGE_SHIFT) return 0; WARN_ON_ONCE(1); return 0; } /* called with gp->tlb_lock held */ static long int __kvmhv_nested_page_fault(struct kvm_vcpu *vcpu, struct kvm_nested_guest *gp) { struct kvm *kvm = vcpu->kvm; struct kvm_memory_slot *memslot; struct rmap_nested *n_rmap; struct kvmppc_pte gpte; pte_t pte, *pte_p; unsigned long mmu_seq; unsigned long dsisr = vcpu->arch.fault_dsisr; unsigned long ea = vcpu->arch.fault_dar; unsigned long *rmapp; unsigned long n_gpa, gpa, gfn, perm = 0UL; unsigned int shift, l1_shift, level; bool writing = !!(dsisr & DSISR_ISSTORE); bool kvm_ro = false; long int ret; if (!gp->l1_gr_to_hr) { kvmhv_update_ptbl_cache(gp); if (!gp->l1_gr_to_hr) return RESUME_HOST; } /* Convert the nested guest real address into a L1 guest real address */ n_gpa = vcpu->arch.fault_gpa & ~0xF000000000000FFFULL; if (!(dsisr & DSISR_PRTABLE_FAULT)) n_gpa |= ea & 0xFFF; ret = kvmhv_translate_addr_nested(vcpu, gp, n_gpa, dsisr, &gpte); /* * If the hardware found a translation but we don't now have a usable * translation in the l1 partition-scoped tree, remove the shadow pte * and let the guest retry. */ if (ret == RESUME_HOST && (dsisr & (DSISR_PROTFAULT | DSISR_BADACCESS | DSISR_NOEXEC_OR_G | DSISR_BAD_COPYPASTE))) goto inval; if (ret) return ret; /* Failed to set the reference/change bits */ if (dsisr & DSISR_SET_RC) { ret = kvmhv_handle_nested_set_rc(vcpu, gp, n_gpa, gpte, dsisr); if (ret == RESUME_HOST) return ret; if (ret) goto inval; dsisr &= ~DSISR_SET_RC; if (!(dsisr & (DSISR_BAD_FAULT_64S | DSISR_NOHPTE | DSISR_PROTFAULT))) return RESUME_GUEST; } /* * We took an HISI or HDSI while we were running a nested guest which * means we have no partition scoped translation for that. This means * we need to insert a pte for the mapping into our shadow_pgtable. */ l1_shift = gpte.page_shift; if (l1_shift < PAGE_SHIFT) { /* We don't support l1 using a page size smaller than our own */ pr_err("KVM: L1 guest page shift (%d) less than our own (%d)\n", l1_shift, PAGE_SHIFT); return -EINVAL; } gpa = gpte.raddr; gfn = gpa >> PAGE_SHIFT; /* 1. Get the corresponding host memslot */ memslot = gfn_to_memslot(kvm, gfn); if (!memslot || (memslot->flags & KVM_MEMSLOT_INVALID)) { if (dsisr & (DSISR_PRTABLE_FAULT | DSISR_BADACCESS)) { /* unusual error -> reflect to the guest as a DSI */ kvmppc_core_queue_data_storage(vcpu, ea, dsisr); return RESUME_GUEST; } /* passthrough of emulated MMIO case... */ pr_err("emulated MMIO passthrough?\n"); return -EINVAL; } if (memslot->flags & KVM_MEM_READONLY) { if (writing) { /* Give the guest a DSI */ kvmppc_core_queue_data_storage(vcpu, ea, DSISR_ISSTORE | DSISR_PROTFAULT); return RESUME_GUEST; } kvm_ro = true; } /* 2. Find the host pte for this L1 guest real address */ /* Used to check for invalidations in progress */ mmu_seq = kvm->mmu_notifier_seq; smp_rmb(); /* See if can find translation in our partition scoped tables for L1 */ pte = __pte(0); spin_lock(&kvm->mmu_lock); pte_p = __find_linux_pte(kvm->arch.pgtable, gpa, NULL, &shift); if (!shift) shift = PAGE_SHIFT; if (pte_p) pte = *pte_p; spin_unlock(&kvm->mmu_lock); if (!pte_present(pte) || (writing && !(pte_val(pte) & _PAGE_WRITE))) { /* No suitable pte found -> try to insert a mapping */ ret = kvmppc_book3s_instantiate_page(vcpu, gpa, memslot, writing, kvm_ro, &pte, &level); if (ret == -EAGAIN) return RESUME_GUEST; else if (ret) return ret; shift = kvmppc_radix_level_to_shift(level); } /* 3. Compute the pte we need to insert for nest_gpa -> host r_addr */ /* The permissions is the combination of the host and l1 guest ptes */ perm |= gpte.may_read ? 0UL : _PAGE_READ; perm |= gpte.may_write ? 0UL : _PAGE_WRITE; perm |= gpte.may_execute ? 0UL : _PAGE_EXEC; pte = __pte(pte_val(pte) & ~perm); /* What size pte can we insert? */ if (shift > l1_shift) { u64 mask; unsigned int actual_shift = PAGE_SHIFT; if (PMD_SHIFT < l1_shift) actual_shift = PMD_SHIFT; mask = (1UL << shift) - (1UL << actual_shift); pte = __pte(pte_val(pte) | (gpa & mask)); shift = actual_shift; } level = kvmppc_radix_shift_to_level(shift); n_gpa &= ~((1UL << shift) - 1); /* 4. Insert the pte into our shadow_pgtable */ n_rmap = kzalloc(sizeof(*n_rmap), GFP_KERNEL); if (!n_rmap) return RESUME_GUEST; /* Let the guest try again */ n_rmap->rmap = (n_gpa & RMAP_NESTED_GPA_MASK) | (((unsigned long) gp->l1_lpid) << RMAP_NESTED_LPID_SHIFT); rmapp = &memslot->arch.rmap[gfn - memslot->base_gfn]; ret = kvmppc_create_pte(kvm, gp->shadow_pgtable, pte, n_gpa, level, mmu_seq, gp->shadow_lpid, rmapp, &n_rmap); if (n_rmap) kfree(n_rmap); if (ret == -EAGAIN) ret = RESUME_GUEST; /* Let the guest try again */ return ret; inval: kvmhv_invalidate_shadow_pte(vcpu, gp, n_gpa, NULL); return RESUME_GUEST; } long int kvmhv_nested_page_fault(struct kvm_vcpu *vcpu) { struct kvm_nested_guest *gp = vcpu->arch.nested; long int ret; mutex_lock(&gp->tlb_lock); ret = __kvmhv_nested_page_fault(vcpu, gp); mutex_unlock(&gp->tlb_lock); return ret; } int kvmhv_nested_next_lpid(struct kvm *kvm, int lpid) { int ret = -1; spin_lock(&kvm->mmu_lock); while (++lpid <= kvm->arch.max_nested_lpid) { if (kvm->arch.nested_guests[lpid]) { ret = lpid; break; } } spin_unlock(&kvm->mmu_lock); return ret; }