if (ret == H_TOO_HARD)
return RESUME_HOST;
break;
+
+ case H_SET_PARTITION_TABLE:
+ ret = H_FUNCTION;
+ if (vcpu->kvm->arch.nested_enable)
+ ret = kvmhv_set_partition_table(vcpu);
+ break;
+ case H_ENTER_NESTED:
+ ret = H_FUNCTION;
+ break;
+ case H_TLB_INVALIDATE:
+ ret = H_FUNCTION;
+ break;
+
default:
return RESUME_HOST;
}
__pa(kvm->arch.pgtable) | RADIX_PGD_INDEX_SIZE;
dw1 = PATB_GR | kvm->arch.process_table;
}
-
- mmu_partition_table_set_entry(kvm->arch.lpid, dw0, dw1);
+ kvmhv_set_ptbl_entry(kvm->arch.lpid, dw0, dw1);
}
/*
/* Must be called with kvm->lock held and mmu_ready = 0 and no vcpus running */
int kvmppc_switch_mmu_to_hpt(struct kvm *kvm)
{
+ if (kvm->arch.nested_enable) {
+ kvm->arch.nested_enable = false;
+ kvmhv_release_all_nested(kvm);
+ }
kvmppc_free_radix(kvm);
kvmppc_update_lpcr(kvm, LPCR_VPM1,
LPCR_VPM1 | LPCR_UPRT | LPCR_GTSE | LPCR_HR);
kvmppc_alloc_host_rm_ops();
+ kvmhv_vm_nested_init(kvm);
+
/*
* Since we don't flush the TLB when tearing down a VM,
* and this lpid might have previously been used,
/* Perform global invalidation and return lpid to the pool */
if (cpu_has_feature(CPU_FTR_ARCH_300)) {
+ if (kvm->arch.nested_enable)
+ kvmhv_release_all_nested(kvm);
kvm->arch.process_table = 0;
- kvmppc_setup_partition_table(kvm);
+ kvmhv_set_ptbl_entry(kvm->arch.lpid, 0, 0);
}
kvmppc_free_lpid(kvm->arch.lpid);
if (r < 0)
return -ENODEV;
+ r = kvmhv_nested_init();
+ if (r)
+ return r;
+
r = kvm_init_subcore_bitmap();
if (r)
return r;
if (kvmppc_radix_possible())
kvmppc_radix_exit();
kvmppc_hv_ops = NULL;
+ kvmhv_nested_exit();
}
module_init(kvmppc_book3s_init_hv);
--- /dev/null
+// 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 <asm/kvm_ppc.h>
+#include <asm/mmu.h>
+#include <asm/pgtable.h>
+#include <asm/pgalloc.h>
+
+static struct patb_entry *pseries_partition_tb;
+
+static void kvmhv_update_ptbl_cache(struct kvm_nested_guest *gp);
+
+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;
+ }
+}
+
+void kvmhv_set_ptbl_entry(unsigned int lpid, u64 dw0, u64 dw1)
+{
+ if (cpu_has_feature(CPU_FTR_HVMODE)) {
+ mmu_partition_table_set_entry(lpid, dw0, dw1);
+ } else {
+ pseries_partition_tb[lpid].patb0 = cpu_to_be64(dw0);
+ pseries_partition_tb[lpid].patb1 = cpu_to_be64(dw1);
+ }
+}
+
+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;
+
+ 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)
+{
+ kvmhv_set_ptbl_entry(gp->shadow_lpid, 0, 0);
+ kvmppc_free_lpid(gp->shadow_lpid);
+ if (gp->shadow_pgtable)
+ pgd_free(gp->l1_host->mm, gp->shadow_pgtable);
+ 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;
+
+ 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);
+ }
+}
+
+/* caller must hold gp->tlb_lock */
+void kvmhv_flush_nested(struct kvm_nested_guest *gp)
+{
+ 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);
+}