diff options
Diffstat (limited to 'arch/powerpc/kvm/book3s_hv_nested.c')
| -rw-r--r-- | arch/powerpc/kvm/book3s_hv_nested.c | 1494 |
1 files changed, 1494 insertions, 0 deletions
diff --git a/arch/powerpc/kvm/book3s_hv_nested.c b/arch/powerpc/kvm/book3s_hv_nested.c new file mode 100644 index 000000000..d0b6c8c16 --- /dev/null +++ b/arch/powerpc/kvm/book3s_hv_nested.c @@ -0,0 +1,1494 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright IBM Corporation, 2018 + * Authors Suraj Jitindar Singh <sjitindarsingh@gmail.com> + * Paul Mackerras <paulus@ozlabs.org> + * + * Description: KVM functions specific to running nested KVM-HV guests + * on Book3S processors (specifically POWER9 and later). + */ + +#include <linux/kernel.h> +#include <linux/kvm_host.h> +#include <linux/llist.h> +#include <linux/pgtable.h> + +#include <asm/kvm_ppc.h> +#include <asm/kvm_book3s.h> +#include <asm/mmu.h> +#include <asm/pgalloc.h> +#include <asm/pte-walk.h> +#include <asm/reg.h> + +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 | PCR_MASK; + 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; +} + +/* Use noinline_for_stack due to https://bugs.llvm.org/show_bug.cgi?id=49610 */ +static noinline_for_stack 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) | PCR_MASK; + 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 | PCR_MASK; + 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; +} + +static void kvmhv_nested_mmio_needed(struct kvm_vcpu *vcpu, u64 regs_ptr) +{ + /* No need to reflect the page fault to L1, we've handled it */ + vcpu->arch.trap = 0; + + /* + * Since the L2 gprs have already been written back into L1 memory when + * we complete the mmio, store the L1 memory location of the L2 gpr + * being loaded into by the mmio so that the loaded value can be + * written there in kvmppc_complete_mmio_load() + */ + if (((vcpu->arch.io_gpr & KVM_MMIO_REG_EXT_MASK) == KVM_MMIO_REG_GPR) + && (vcpu->mmio_is_write == 0)) { + vcpu->arch.nested_io_gpr = (gpa_t) regs_ptr + + offsetof(struct pt_regs, + gpr[vcpu->arch.io_gpr]); + vcpu->arch.io_gpr = KVM_MMIO_REG_NESTED_GPR; + } +} + +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; + + if (MSR_TM_TRANSACTIONAL(vcpu->arch.shregs.msr)) + return H_BAD_MODE; + + /* copy parameters in */ + hv_ptr = kvmppc_get_gpr(vcpu, 4); + regs_ptr = kvmppc_get_gpr(vcpu, 5); + vcpu->srcu_idx = srcu_read_lock(&vcpu->kvm->srcu); + err = kvm_vcpu_read_guest(vcpu, hv_ptr, &l2_hv, + sizeof(struct hv_guest_state)) || + kvm_vcpu_read_guest(vcpu, regs_ptr, &l2_regs, + sizeof(struct pt_regs)); + srcu_read_unlock(&vcpu->kvm->srcu, vcpu->srcu_idx); + 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; + + if (kvmppc_need_byteswap(vcpu)) + byteswap_pt_regs(&l2_regs); + if (l2_hv.vcpu_token >= NR_CPUS) + return H_PARAMETER; + + /* + * L1 must have set up a suspended state to enter the L2 in a + * transactional state, and only in that case. These have to be + * filtered out here to prevent causing a TM Bad Thing in the + * host HRFID. We could synthesize a TM Bad Thing back to the L1 + * here but there doesn't seem like much point. + */ + if (MSR_TM_SUSPENDED(vcpu->arch.shregs.msr)) { + if (!MSR_TM_ACTIVE(l2_regs.msr)) + return H_BAD_MODE; + } else { + if (l2_regs.msr & MSR_TS_MASK) + return H_BAD_MODE; + if (WARN_ON_ONCE(vcpu->arch.shregs.msr & MSR_TS_MASK)) + return H_BAD_MODE; + } + + /* 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, 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); + } + vcpu->srcu_idx = srcu_read_lock(&vcpu->kvm->srcu); + err = kvm_vcpu_write_guest(vcpu, hv_ptr, &l2_hv, + sizeof(struct hv_guest_state)) || + kvm_vcpu_write_guest(vcpu, regs_ptr, &l2_regs, + sizeof(struct pt_regs)); + srcu_read_unlock(&vcpu->kvm->srcu, vcpu->srcu_idx); + if (err) + return H_AUTHORITY; + + if (r == -EINTR) + return H_INTERRUPT; + + if (vcpu->mmio_needed) { + kvmhv_nested_mmio_needed(vcpu, regs_ptr); + return H_TOO_HARD; + } + + 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_all_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, true); + 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; +} + +/* + * Handle the H_COPY_TOFROM_GUEST hcall. + * r4 = L1 lpid of nested guest + * r5 = pid + * r6 = eaddr to access + * r7 = to buffer (L1 gpa) + * r8 = from buffer (L1 gpa) + * r9 = n bytes to copy + */ +long kvmhv_copy_tofrom_guest_nested(struct kvm_vcpu *vcpu) +{ + struct kvm_nested_guest *gp; + int l1_lpid = kvmppc_get_gpr(vcpu, 4); + int pid = kvmppc_get_gpr(vcpu, 5); + gva_t eaddr = kvmppc_get_gpr(vcpu, 6); + gpa_t gp_to = (gpa_t) kvmppc_get_gpr(vcpu, 7); + gpa_t gp_from = (gpa_t) kvmppc_get_gpr(vcpu, 8); + void *buf; + unsigned long n = kvmppc_get_gpr(vcpu, 9); + bool is_load = !!gp_to; + long rc; + + if (gp_to && gp_from) /* One must be NULL to determine the direction */ + return H_PARAMETER; + + if (eaddr & (0xFFFUL << 52)) + return H_PARAMETER; + + buf = kzalloc(n, GFP_KERNEL | __GFP_NOWARN); + if (!buf) + return H_NO_MEM; + + gp = kvmhv_get_nested(vcpu->kvm, l1_lpid, false); + if (!gp) { + rc = H_PARAMETER; + goto out_free; + } + + mutex_lock(&gp->tlb_lock); + + if (is_load) { + /* Load from the nested guest into our buffer */ + rc = __kvmhv_copy_tofrom_guest_radix(gp->shadow_lpid, pid, + eaddr, buf, NULL, n); + if (rc) + goto not_found; + + /* Write what was loaded into our buffer back to the L1 guest */ + vcpu->srcu_idx = srcu_read_lock(&vcpu->kvm->srcu); + rc = kvm_vcpu_write_guest(vcpu, gp_to, buf, n); + srcu_read_unlock(&vcpu->kvm->srcu, vcpu->srcu_idx); + if (rc) + goto not_found; + } else { + /* Load the data to be stored from the L1 guest into our buf */ + vcpu->srcu_idx = srcu_read_lock(&vcpu->kvm->srcu); + rc = kvm_vcpu_read_guest(vcpu, gp_from, buf, n); + srcu_read_unlock(&vcpu->kvm->srcu, vcpu->srcu_idx); + if (rc) + goto not_found; + + /* Store from our buffer into the nested guest */ + rc = __kvmhv_copy_tofrom_guest_radix(gp->shadow_lpid, pid, + eaddr, NULL, buf, n); + if (rc) + goto not_found; + } + +out_unlock: + mutex_unlock(&gp->tlb_lock); + kvmhv_put_nested(gp); +out_free: + kfree(buf); + return rc; +not_found: + rc = H_NOT_FOUND; + goto out_unlock; +} + +/* + * 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))) { + int srcu_idx = srcu_read_lock(&kvm->srcu); + ret = kvm_read_guest(kvm, ptbl_addr, + &ptbl_entry, sizeof(ptbl_entry)); + srcu_read_unlock(&kvm->srcu, srcu_idx); + } + 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); +} + +static 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]; +} + +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 | + 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_update_nest_rmap_rc(struct kvm *kvm, u64 n_rmap, + unsigned long clr, unsigned long set, + unsigned long hpa, unsigned long mask) +{ + 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; + + /* Find the pte */ + 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 + * 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) +{ + 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_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); +} + +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_kvm_nested_guest_pte(kvm, gp->l1_lpid, gpa, &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_G_OR_CIP; + 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 &= SRR1_MSR_BITS; + 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; + long 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, false, writing, + gpte.raddr, kvm->arch.lpid); + if (!ret) { + ret = -EINVAL; + goto out_unlock; + } + + /* Set the rc bit in the pte of the shadow_pgtable for the nest guest */ + ret = kvmppc_hv_handle_set_rc(kvm, true, writing, + n_gpa, gp->l1_lpid); + if (!ret) + ret = -EINVAL; + else + ret = 0; + +out_unlock: + spin_unlock(&kvm->mmu_lock); + return ret; +} + +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 */ + return kvmppc_hv_emulate_mmio(vcpu, gpa, ea, writing); + } + 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_kvm_secondary_pte(kvm, gpa, &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); + } + /* Align gfn to the start of the page */ + gfn = (gpa & ~((1UL << shift) - 1)) >> PAGE_SHIFT; + + /* 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; + /* Only set accessed/dirty (rc) bits if set in host and l1 guest ptes */ + perm |= (gpte.rc & _PAGE_ACCESSED) ? 0UL : _PAGE_ACCESSED; + perm |= ((gpte.rc & _PAGE_DIRTY) && writing) ? 0UL : _PAGE_DIRTY; + 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); + 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; +} |