Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 894 insertions, 0 deletions

diff --git a/arch/s390/kvm/pv.c b/arch/s390/kvm/pv.c
new file mode 100644
index 0000000000..75e81ba26d
--- /dev/null
+++ b/arch/s390/kvm/pv.c
@@ -0,0 +1,894 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Hosting Protected Virtual Machines
+ *
+ * Copyright IBM Corp. 2019, 2020
+ *    Author(s): Janosch Frank <frankja@linux.ibm.com>
+ */
+#include <linux/kvm.h>
+#include <linux/kvm_host.h>
+#include <linux/minmax.h>
+#include <linux/pagemap.h>
+#include <linux/sched/signal.h>
+#include <asm/gmap.h>
+#include <asm/uv.h>
+#include <asm/mman.h>
+#include <linux/pagewalk.h>
+#include <linux/sched/mm.h>
+#include <linux/mmu_notifier.h>
+#include "kvm-s390.h"
+
+bool kvm_s390_pv_is_protected(struct kvm *kvm)
+{
+	lockdep_assert_held(&kvm->lock);
+	return !!kvm_s390_pv_get_handle(kvm);
+}
+EXPORT_SYMBOL_GPL(kvm_s390_pv_is_protected);
+
+bool kvm_s390_pv_cpu_is_protected(struct kvm_vcpu *vcpu)
+{
+	lockdep_assert_held(&vcpu->mutex);
+	return !!kvm_s390_pv_cpu_get_handle(vcpu);
+}
+EXPORT_SYMBOL_GPL(kvm_s390_pv_cpu_is_protected);
+
+/**
+ * struct pv_vm_to_be_destroyed - Represents a protected VM that needs to
+ * be destroyed
+ *
+ * @list: list head for the list of leftover VMs
+ * @old_gmap_table: the gmap table of the leftover protected VM
+ * @handle: the handle of the leftover protected VM
+ * @stor_var: pointer to the variable storage of the leftover protected VM
+ * @stor_base: address of the base storage of the leftover protected VM
+ *
+ * Represents a protected VM that is still registered with the Ultravisor,
+ * but which does not correspond any longer to an active KVM VM. It should
+ * be destroyed at some point later, either asynchronously or when the
+ * process terminates.
+ */
+struct pv_vm_to_be_destroyed {
+	struct list_head list;
+	unsigned long old_gmap_table;
+	u64 handle;
+	void *stor_var;
+	unsigned long stor_base;
+};
+
+static void kvm_s390_clear_pv_state(struct kvm *kvm)
+{
+	kvm->arch.pv.handle = 0;
+	kvm->arch.pv.guest_len = 0;
+	kvm->arch.pv.stor_base = 0;
+	kvm->arch.pv.stor_var = NULL;
+}
+
+int kvm_s390_pv_destroy_cpu(struct kvm_vcpu *vcpu, u16 *rc, u16 *rrc)
+{
+	int cc;
+
+	if (!kvm_s390_pv_cpu_get_handle(vcpu))
+		return 0;
+
+	cc = uv_cmd_nodata(kvm_s390_pv_cpu_get_handle(vcpu), UVC_CMD_DESTROY_SEC_CPU, rc, rrc);
+
+	KVM_UV_EVENT(vcpu->kvm, 3, "PROTVIRT DESTROY VCPU %d: rc %x rrc %x",
+		     vcpu->vcpu_id, *rc, *rrc);
+	WARN_ONCE(cc, "protvirt destroy cpu failed rc %x rrc %x", *rc, *rrc);
+
+	/* Intended memory leak for something that should never happen. */
+	if (!cc)
+		free_pages(vcpu->arch.pv.stor_base,
+			   get_order(uv_info.guest_cpu_stor_len));
+
+	free_page((unsigned long)sida_addr(vcpu->arch.sie_block));
+	vcpu->arch.sie_block->pv_handle_cpu = 0;
+	vcpu->arch.sie_block->pv_handle_config = 0;
+	memset(&vcpu->arch.pv, 0, sizeof(vcpu->arch.pv));
+	vcpu->arch.sie_block->sdf = 0;
+	/*
+	 * The sidad field (for sdf == 2) is now the gbea field (for sdf == 0).
+	 * Use the reset value of gbea to avoid leaking the kernel pointer of
+	 * the just freed sida.
+	 */
+	vcpu->arch.sie_block->gbea = 1;
+	kvm_make_request(KVM_REQ_TLB_FLUSH, vcpu);
+
+	return cc ? EIO : 0;
+}
+
+int kvm_s390_pv_create_cpu(struct kvm_vcpu *vcpu, u16 *rc, u16 *rrc)
+{
+	struct uv_cb_csc uvcb = {
+		.header.cmd = UVC_CMD_CREATE_SEC_CPU,
+		.header.len = sizeof(uvcb),
+	};
+	void *sida_addr;
+	int cc;
+
+	if (kvm_s390_pv_cpu_get_handle(vcpu))
+		return -EINVAL;
+
+	vcpu->arch.pv.stor_base = __get_free_pages(GFP_KERNEL_ACCOUNT,
+						   get_order(uv_info.guest_cpu_stor_len));
+	if (!vcpu->arch.pv.stor_base)
+		return -ENOMEM;
+
+	/* Input */
+	uvcb.guest_handle = kvm_s390_pv_get_handle(vcpu->kvm);
+	uvcb.num = vcpu->arch.sie_block->icpua;
+	uvcb.state_origin = virt_to_phys(vcpu->arch.sie_block);
+	uvcb.stor_origin = virt_to_phys((void *)vcpu->arch.pv.stor_base);
+
+	/* Alloc Secure Instruction Data Area Designation */
+	sida_addr = (void *)__get_free_page(GFP_KERNEL_ACCOUNT | __GFP_ZERO);
+	if (!sida_addr) {
+		free_pages(vcpu->arch.pv.stor_base,
+			   get_order(uv_info.guest_cpu_stor_len));
+		return -ENOMEM;
+	}
+	vcpu->arch.sie_block->sidad = virt_to_phys(sida_addr);
+
+	cc = uv_call(0, (u64)&uvcb);
+	*rc = uvcb.header.rc;
+	*rrc = uvcb.header.rrc;
+	KVM_UV_EVENT(vcpu->kvm, 3,
+		     "PROTVIRT CREATE VCPU: cpu %d handle %llx rc %x rrc %x",
+		     vcpu->vcpu_id, uvcb.cpu_handle, uvcb.header.rc,
+		     uvcb.header.rrc);
+
+	if (cc) {
+		u16 dummy;
+
+		kvm_s390_pv_destroy_cpu(vcpu, &dummy, &dummy);
+		return -EIO;
+	}
+
+	/* Output */
+	vcpu->arch.pv.handle = uvcb.cpu_handle;
+	vcpu->arch.sie_block->pv_handle_cpu = uvcb.cpu_handle;
+	vcpu->arch.sie_block->pv_handle_config = kvm_s390_pv_get_handle(vcpu->kvm);
+	vcpu->arch.sie_block->sdf = 2;
+	kvm_make_request(KVM_REQ_TLB_FLUSH, vcpu);
+	return 0;
+}
+
+/* only free resources when the destroy was successful */
+static void kvm_s390_pv_dealloc_vm(struct kvm *kvm)
+{
+	vfree(kvm->arch.pv.stor_var);
+	free_pages(kvm->arch.pv.stor_base,
+		   get_order(uv_info.guest_base_stor_len));
+	kvm_s390_clear_pv_state(kvm);
+}
+
+static int kvm_s390_pv_alloc_vm(struct kvm *kvm)
+{
+	unsigned long base = uv_info.guest_base_stor_len;
+	unsigned long virt = uv_info.guest_virt_var_stor_len;
+	unsigned long npages = 0, vlen = 0;
+
+	kvm->arch.pv.stor_var = NULL;
+	kvm->arch.pv.stor_base = __get_free_pages(GFP_KERNEL_ACCOUNT, get_order(base));
+	if (!kvm->arch.pv.stor_base)
+		return -ENOMEM;
+
+	/*
+	 * Calculate current guest storage for allocation of the
+	 * variable storage, which is based on the length in MB.
+	 *
+	 * Slots are sorted by GFN
+	 */
+	mutex_lock(&kvm->slots_lock);
+	npages = kvm_s390_get_gfn_end(kvm_memslots(kvm));
+	mutex_unlock(&kvm->slots_lock);
+
+	kvm->arch.pv.guest_len = npages * PAGE_SIZE;
+
+	/* Allocate variable storage */
+	vlen = ALIGN(virt * ((npages * PAGE_SIZE) / HPAGE_SIZE), PAGE_SIZE);
+	vlen += uv_info.guest_virt_base_stor_len;
+	kvm->arch.pv.stor_var = vzalloc(vlen);
+	if (!kvm->arch.pv.stor_var)
+		goto out_err;
+	return 0;
+
+out_err:
+	kvm_s390_pv_dealloc_vm(kvm);
+	return -ENOMEM;
+}
+
+/**
+ * kvm_s390_pv_dispose_one_leftover - Clean up one leftover protected VM.
+ * @kvm: the KVM that was associated with this leftover protected VM
+ * @leftover: details about the leftover protected VM that needs a clean up
+ * @rc: the RC code of the Destroy Secure Configuration UVC
+ * @rrc: the RRC code of the Destroy Secure Configuration UVC
+ *
+ * Destroy one leftover protected VM.
+ * On success, kvm->mm->context.protected_count will be decremented atomically
+ * and all other resources used by the VM will be freed.
+ *
+ * Return: 0 in case of success, otherwise 1
+ */
+static int kvm_s390_pv_dispose_one_leftover(struct kvm *kvm,
+					    struct pv_vm_to_be_destroyed *leftover,
+					    u16 *rc, u16 *rrc)
+{
+	int cc;
+
+	/* It used the destroy-fast UVC, nothing left to do here */
+	if (!leftover->handle)
+		goto done_fast;
+	cc = uv_cmd_nodata(leftover->handle, UVC_CMD_DESTROY_SEC_CONF, rc, rrc);
+	KVM_UV_EVENT(kvm, 3, "PROTVIRT DESTROY LEFTOVER VM: rc %x rrc %x", *rc, *rrc);
+	WARN_ONCE(cc, "protvirt destroy leftover vm failed rc %x rrc %x", *rc, *rrc);
+	if (cc)
+		return cc;
+	/*
+	 * Intentionally leak unusable memory. If the UVC fails, the memory
+	 * used for the VM and its metadata is permanently unusable.
+	 * This can only happen in case of a serious KVM or hardware bug; it
+	 * is not expected to happen in normal operation.
+	 */
+	free_pages(leftover->stor_base, get_order(uv_info.guest_base_stor_len));
+	free_pages(leftover->old_gmap_table, CRST_ALLOC_ORDER);
+	vfree(leftover->stor_var);
+done_fast:
+	atomic_dec(&kvm->mm->context.protected_count);
+	return 0;
+}
+
+/**
+ * kvm_s390_destroy_lower_2g - Destroy the first 2GB of protected guest memory.
+ * @kvm: the VM whose memory is to be cleared.
+ *
+ * Destroy the first 2GB of guest memory, to avoid prefix issues after reboot.
+ * The CPUs of the protected VM need to be destroyed beforehand.
+ */
+static void kvm_s390_destroy_lower_2g(struct kvm *kvm)
+{
+	const unsigned long pages_2g = SZ_2G / PAGE_SIZE;
+	struct kvm_memory_slot *slot;
+	unsigned long len;
+	int srcu_idx;
+
+	srcu_idx = srcu_read_lock(&kvm->srcu);
+
+	/* Take the memslot containing guest absolute address 0 */
+	slot = gfn_to_memslot(kvm, 0);
+	/* Clear all slots or parts thereof that are below 2GB */
+	while (slot && slot->base_gfn < pages_2g) {
+		len = min_t(u64, slot->npages, pages_2g - slot->base_gfn) * PAGE_SIZE;
+		s390_uv_destroy_range(kvm->mm, slot->userspace_addr, slot->userspace_addr + len);
+		/* Take the next memslot */
+		slot = gfn_to_memslot(kvm, slot->base_gfn + slot->npages);
+	}
+
+	srcu_read_unlock(&kvm->srcu, srcu_idx);
+}
+
+static int kvm_s390_pv_deinit_vm_fast(struct kvm *kvm, u16 *rc, u16 *rrc)
+{
+	struct uv_cb_destroy_fast uvcb = {
+		.header.cmd = UVC_CMD_DESTROY_SEC_CONF_FAST,
+		.header.len = sizeof(uvcb),
+		.handle = kvm_s390_pv_get_handle(kvm),
+	};
+	int cc;
+
+	cc = uv_call_sched(0, (u64)&uvcb);
+	if (rc)
+		*rc = uvcb.header.rc;
+	if (rrc)
+		*rrc = uvcb.header.rrc;
+	WRITE_ONCE(kvm->arch.gmap->guest_handle, 0);
+	KVM_UV_EVENT(kvm, 3, "PROTVIRT DESTROY VM FAST: rc %x rrc %x",
+		     uvcb.header.rc, uvcb.header.rrc);
+	WARN_ONCE(cc && uvcb.header.rc != 0x104,
+		  "protvirt destroy vm fast failed handle %llx rc %x rrc %x",
+		  kvm_s390_pv_get_handle(kvm), uvcb.header.rc, uvcb.header.rrc);
+	/* Intended memory leak on "impossible" error */
+	if (!cc)
+		kvm_s390_pv_dealloc_vm(kvm);
+	return cc ? -EIO : 0;
+}
+
+static inline bool is_destroy_fast_available(void)
+{
+	return test_bit_inv(BIT_UVC_CMD_DESTROY_SEC_CONF_FAST, uv_info.inst_calls_list);
+}
+
+/**
+ * kvm_s390_pv_set_aside - Set aside a protected VM for later teardown.
+ * @kvm: the VM
+ * @rc: return value for the RC field of the UVCB
+ * @rrc: return value for the RRC field of the UVCB
+ *
+ * Set aside the protected VM for a subsequent teardown. The VM will be able
+ * to continue immediately as a non-secure VM, and the information needed to
+ * properly tear down the protected VM is set aside. If another protected VM
+ * was already set aside without starting its teardown, this function will
+ * fail.
+ * The CPUs of the protected VM need to be destroyed beforehand.
+ *
+ * Context: kvm->lock needs to be held
+ *
+ * Return: 0 in case of success, -EINVAL if another protected VM was already set
+ * aside, -ENOMEM if the system ran out of memory.
+ */
+int kvm_s390_pv_set_aside(struct kvm *kvm, u16 *rc, u16 *rrc)
+{
+	struct pv_vm_to_be_destroyed *priv;
+	int res = 0;
+
+	lockdep_assert_held(&kvm->lock);
+	/*
+	 * If another protected VM was already prepared for teardown, refuse.
+	 * A normal deinitialization has to be performed instead.
+	 */
+	if (kvm->arch.pv.set_aside)
+		return -EINVAL;
+
+	/* Guest with segment type ASCE, refuse to destroy asynchronously */
+	if ((kvm->arch.gmap->asce & _ASCE_TYPE_MASK) == _ASCE_TYPE_SEGMENT)
+		return -EINVAL;
+
+	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	if (is_destroy_fast_available()) {
+		res = kvm_s390_pv_deinit_vm_fast(kvm, rc, rrc);
+	} else {
+		priv->stor_var = kvm->arch.pv.stor_var;
+		priv->stor_base = kvm->arch.pv.stor_base;
+		priv->handle = kvm_s390_pv_get_handle(kvm);
+		priv->old_gmap_table = (unsigned long)kvm->arch.gmap->table;
+		WRITE_ONCE(kvm->arch.gmap->guest_handle, 0);
+		if (s390_replace_asce(kvm->arch.gmap))
+			res = -ENOMEM;
+	}
+
+	if (res) {
+		kfree(priv);
+		return res;
+	}
+
+	kvm_s390_destroy_lower_2g(kvm);
+	kvm_s390_clear_pv_state(kvm);
+	kvm->arch.pv.set_aside = priv;
+
+	*rc = UVC_RC_EXECUTED;
+	*rrc = 42;
+	return 0;
+}
+
+/**
+ * kvm_s390_pv_deinit_vm - Deinitialize the current protected VM
+ * @kvm: the KVM whose protected VM needs to be deinitialized
+ * @rc: the RC code of the UVC
+ * @rrc: the RRC code of the UVC
+ *
+ * Deinitialize the current protected VM. This function will destroy and
+ * cleanup the current protected VM, but it will not cleanup the guest
+ * memory. This function should only be called when the protected VM has
+ * just been created and therefore does not have any guest memory, or when
+ * the caller cleans up the guest memory separately.
+ *
+ * This function should not fail, but if it does, the donated memory must
+ * not be freed.
+ *
+ * Context: kvm->lock needs to be held
+ *
+ * Return: 0 in case of success, otherwise -EIO
+ */
+int kvm_s390_pv_deinit_vm(struct kvm *kvm, u16 *rc, u16 *rrc)
+{
+	int cc;
+
+	cc = uv_cmd_nodata(kvm_s390_pv_get_handle(kvm),
+			   UVC_CMD_DESTROY_SEC_CONF, rc, rrc);
+	WRITE_ONCE(kvm->arch.gmap->guest_handle, 0);
+	if (!cc) {
+		atomic_dec(&kvm->mm->context.protected_count);
+		kvm_s390_pv_dealloc_vm(kvm);
+	} else {
+		/* Intended memory leak on "impossible" error */
+		s390_replace_asce(kvm->arch.gmap);
+	}
+	KVM_UV_EVENT(kvm, 3, "PROTVIRT DESTROY VM: rc %x rrc %x", *rc, *rrc);
+	WARN_ONCE(cc, "protvirt destroy vm failed rc %x rrc %x", *rc, *rrc);
+
+	return cc ? -EIO : 0;
+}
+
+/**
+ * kvm_s390_pv_deinit_cleanup_all - Clean up all protected VMs associated
+ * with a specific KVM.
+ * @kvm: the KVM to be cleaned up
+ * @rc: the RC code of the first failing UVC
+ * @rrc: the RRC code of the first failing UVC
+ *
+ * This function will clean up all protected VMs associated with a KVM.
+ * This includes the active one, the one prepared for deinitialization with
+ * kvm_s390_pv_set_aside, and any still pending in the need_cleanup list.
+ *
+ * Context: kvm->lock needs to be held unless being called from
+ * kvm_arch_destroy_vm.
+ *
+ * Return: 0 if all VMs are successfully cleaned up, otherwise -EIO
+ */
+int kvm_s390_pv_deinit_cleanup_all(struct kvm *kvm, u16 *rc, u16 *rrc)
+{
+	struct pv_vm_to_be_destroyed *cur;
+	bool need_zap = false;
+	u16 _rc, _rrc;
+	int cc = 0;
+
+	/*
+	 * Nothing to do if the counter was already 0. Otherwise make sure
+	 * the counter does not reach 0 before calling s390_uv_destroy_range.
+	 */
+	if (!atomic_inc_not_zero(&kvm->mm->context.protected_count))
+		return 0;
+
+	*rc = 1;
+	/* If the current VM is protected, destroy it */
+	if (kvm_s390_pv_get_handle(kvm)) {
+		cc = kvm_s390_pv_deinit_vm(kvm, rc, rrc);
+		need_zap = true;
+	}
+
+	/* If a previous protected VM was set aside, put it in the need_cleanup list */
+	if (kvm->arch.pv.set_aside) {
+		list_add(kvm->arch.pv.set_aside, &kvm->arch.pv.need_cleanup);
+		kvm->arch.pv.set_aside = NULL;
+	}
+
+	/* Cleanup all protected VMs in the need_cleanup list */
+	while (!list_empty(&kvm->arch.pv.need_cleanup)) {
+		cur = list_first_entry(&kvm->arch.pv.need_cleanup, typeof(*cur), list);
+		need_zap = true;
+		if (kvm_s390_pv_dispose_one_leftover(kvm, cur, &_rc, &_rrc)) {
+			cc = 1;
+			/*
+			 * Only return the first error rc and rrc, so make
+			 * sure it is not overwritten. All destroys will
+			 * additionally be reported via KVM_UV_EVENT().
+			 */
+			if (*rc == UVC_RC_EXECUTED) {
+				*rc = _rc;
+				*rrc = _rrc;
+			}
+		}
+		list_del(&cur->list);
+		kfree(cur);
+	}
+
+	/*
+	 * If the mm still has a mapping, try to mark all its pages as
+	 * accessible. The counter should not reach zero before this
+	 * cleanup has been performed.
+	 */
+	if (need_zap && mmget_not_zero(kvm->mm)) {
+		s390_uv_destroy_range(kvm->mm, 0, TASK_SIZE);
+		mmput(kvm->mm);
+	}
+
+	/* Now the counter can safely reach 0 */
+	atomic_dec(&kvm->mm->context.protected_count);
+	return cc ? -EIO : 0;
+}
+
+/**
+ * kvm_s390_pv_deinit_aside_vm - Teardown a previously set aside protected VM.
+ * @kvm: the VM previously associated with the protected VM
+ * @rc: return value for the RC field of the UVCB
+ * @rrc: return value for the RRC field of the UVCB
+ *
+ * Tear down the protected VM that had been previously prepared for teardown
+ * using kvm_s390_pv_set_aside_vm. Ideally this should be called by
+ * userspace asynchronously from a separate thread.
+ *
+ * Context: kvm->lock must not be held.
+ *
+ * Return: 0 in case of success, -EINVAL if no protected VM had been
+ * prepared for asynchronous teardowm, -EIO in case of other errors.
+ */
+int kvm_s390_pv_deinit_aside_vm(struct kvm *kvm, u16 *rc, u16 *rrc)
+{
+	struct pv_vm_to_be_destroyed *p;
+	int ret = 0;
+
+	lockdep_assert_not_held(&kvm->lock);
+	mutex_lock(&kvm->lock);
+	p = kvm->arch.pv.set_aside;
+	kvm->arch.pv.set_aside = NULL;
+	mutex_unlock(&kvm->lock);
+	if (!p)
+		return -EINVAL;
+
+	/* When a fatal signal is received, stop immediately */
+	if (s390_uv_destroy_range_interruptible(kvm->mm, 0, TASK_SIZE_MAX))
+		goto done;
+	if (kvm_s390_pv_dispose_one_leftover(kvm, p, rc, rrc))
+		ret = -EIO;
+	kfree(p);
+	p = NULL;
+done:
+	/*
+	 * p is not NULL if we aborted because of a fatal signal, in which
+	 * case queue the leftover for later cleanup.
+	 */
+	if (p) {
+		mutex_lock(&kvm->lock);
+		list_add(&p->list, &kvm->arch.pv.need_cleanup);
+		mutex_unlock(&kvm->lock);
+		/* Did not finish, but pretend things went well */
+		*rc = UVC_RC_EXECUTED;
+		*rrc = 42;
+	}
+	return ret;
+}
+
+static void kvm_s390_pv_mmu_notifier_release(struct mmu_notifier *subscription,
+					     struct mm_struct *mm)
+{
+	struct kvm *kvm = container_of(subscription, struct kvm, arch.pv.mmu_notifier);
+	u16 dummy;
+	int r;
+
+	/*
+	 * No locking is needed since this is the last thread of the last user of this
+	 * struct mm.
+	 * When the struct kvm gets deinitialized, this notifier is also
+	 * unregistered. This means that if this notifier runs, then the
+	 * struct kvm is still valid.
+	 */
+	r = kvm_s390_cpus_from_pv(kvm, &dummy, &dummy);
+	if (!r && is_destroy_fast_available() && kvm_s390_pv_get_handle(kvm))
+		kvm_s390_pv_deinit_vm_fast(kvm, &dummy, &dummy);
+}
+
+static const struct mmu_notifier_ops kvm_s390_pv_mmu_notifier_ops = {
+	.release = kvm_s390_pv_mmu_notifier_release,
+};
+
+int kvm_s390_pv_init_vm(struct kvm *kvm, u16 *rc, u16 *rrc)
+{
+	struct uv_cb_cgc uvcb = {
+		.header.cmd = UVC_CMD_CREATE_SEC_CONF,
+		.header.len = sizeof(uvcb)
+	};
+	int cc, ret;
+	u16 dummy;
+
+	ret = kvm_s390_pv_alloc_vm(kvm);
+	if (ret)
+		return ret;
+
+	/* Inputs */
+	uvcb.guest_stor_origin = 0; /* MSO is 0 for KVM */
+	uvcb.guest_stor_len = kvm->arch.pv.guest_len;
+	uvcb.guest_asce = kvm->arch.gmap->asce;
+	uvcb.guest_sca = virt_to_phys(kvm->arch.sca);
+	uvcb.conf_base_stor_origin =
+		virt_to_phys((void *)kvm->arch.pv.stor_base);
+	uvcb.conf_virt_stor_origin = (u64)kvm->arch.pv.stor_var;
+	uvcb.flags.ap_allow_instr = kvm->arch.model.uv_feat_guest.ap;
+	uvcb.flags.ap_instr_intr = kvm->arch.model.uv_feat_guest.ap_intr;
+
+	cc = uv_call_sched(0, (u64)&uvcb);
+	*rc = uvcb.header.rc;
+	*rrc = uvcb.header.rrc;
+	KVM_UV_EVENT(kvm, 3, "PROTVIRT CREATE VM: handle %llx len %llx rc %x rrc %x flags %04x",
+		     uvcb.guest_handle, uvcb.guest_stor_len, *rc, *rrc, uvcb.flags.raw);
+
+	/* Outputs */
+	kvm->arch.pv.handle = uvcb.guest_handle;
+
+	atomic_inc(&kvm->mm->context.protected_count);
+	if (cc) {
+		if (uvcb.header.rc & UVC_RC_NEED_DESTROY) {
+			kvm_s390_pv_deinit_vm(kvm, &dummy, &dummy);
+		} else {
+			atomic_dec(&kvm->mm->context.protected_count);
+			kvm_s390_pv_dealloc_vm(kvm);
+		}
+		return -EIO;
+	}
+	kvm->arch.gmap->guest_handle = uvcb.guest_handle;
+	/* Add the notifier only once. No races because we hold kvm->lock */
+	if (kvm->arch.pv.mmu_notifier.ops != &kvm_s390_pv_mmu_notifier_ops) {
+		kvm->arch.pv.mmu_notifier.ops = &kvm_s390_pv_mmu_notifier_ops;
+		mmu_notifier_register(&kvm->arch.pv.mmu_notifier, kvm->mm);
+	}
+	return 0;
+}
+
+int kvm_s390_pv_set_sec_parms(struct kvm *kvm, void *hdr, u64 length, u16 *rc,
+			      u16 *rrc)
+{
+	struct uv_cb_ssc uvcb = {
+		.header.cmd = UVC_CMD_SET_SEC_CONF_PARAMS,
+		.header.len = sizeof(uvcb),
+		.sec_header_origin = (u64)hdr,
+		.sec_header_len = length,
+		.guest_handle = kvm_s390_pv_get_handle(kvm),
+	};
+	int cc = uv_call(0, (u64)&uvcb);
+
+	*rc = uvcb.header.rc;
+	*rrc = uvcb.header.rrc;
+	KVM_UV_EVENT(kvm, 3, "PROTVIRT VM SET PARMS: rc %x rrc %x",
+		     *rc, *rrc);
+	return cc ? -EINVAL : 0;
+}
+
+static int unpack_one(struct kvm *kvm, unsigned long addr, u64 tweak,
+		      u64 offset, u16 *rc, u16 *rrc)
+{
+	struct uv_cb_unp uvcb = {
+		.header.cmd = UVC_CMD_UNPACK_IMG,
+		.header.len = sizeof(uvcb),
+		.guest_handle = kvm_s390_pv_get_handle(kvm),
+		.gaddr = addr,
+		.tweak[0] = tweak,
+		.tweak[1] = offset,
+	};
+	int ret = gmap_make_secure(kvm->arch.gmap, addr, &uvcb);
+
+	*rc = uvcb.header.rc;
+	*rrc = uvcb.header.rrc;
+
+	if (ret && ret != -EAGAIN)
+		KVM_UV_EVENT(kvm, 3, "PROTVIRT VM UNPACK: failed addr %llx with rc %x rrc %x",
+			     uvcb.gaddr, *rc, *rrc);
+	return ret;
+}
+
+int kvm_s390_pv_unpack(struct kvm *kvm, unsigned long addr, unsigned long size,
+		       unsigned long tweak, u16 *rc, u16 *rrc)
+{
+	u64 offset = 0;
+	int ret = 0;
+
+	if (addr & ~PAGE_MASK || !size || size & ~PAGE_MASK)
+		return -EINVAL;
+
+	KVM_UV_EVENT(kvm, 3, "PROTVIRT VM UNPACK: start addr %lx size %lx",
+		     addr, size);
+
+	while (offset < size) {
+		ret = unpack_one(kvm, addr, tweak, offset, rc, rrc);
+		if (ret == -EAGAIN) {
+			cond_resched();
+			if (fatal_signal_pending(current))
+				break;
+			continue;
+		}
+		if (ret)
+			break;
+		addr += PAGE_SIZE;
+		offset += PAGE_SIZE;
+	}
+	if (!ret)
+		KVM_UV_EVENT(kvm, 3, "%s", "PROTVIRT VM UNPACK: successful");
+	return ret;
+}
+
+int kvm_s390_pv_set_cpu_state(struct kvm_vcpu *vcpu, u8 state)
+{
+	struct uv_cb_cpu_set_state uvcb = {
+		.header.cmd	= UVC_CMD_CPU_SET_STATE,
+		.header.len	= sizeof(uvcb),
+		.cpu_handle	= kvm_s390_pv_cpu_get_handle(vcpu),
+		.state		= state,
+	};
+	int cc;
+
+	cc = uv_call(0, (u64)&uvcb);
+	KVM_UV_EVENT(vcpu->kvm, 3, "PROTVIRT SET CPU %d STATE %d rc %x rrc %x",
+		     vcpu->vcpu_id, state, uvcb.header.rc, uvcb.header.rrc);
+	if (cc)
+		return -EINVAL;
+	return 0;
+}
+
+int kvm_s390_pv_dump_cpu(struct kvm_vcpu *vcpu, void *buff, u16 *rc, u16 *rrc)
+{
+	struct uv_cb_dump_cpu uvcb = {
+		.header.cmd = UVC_CMD_DUMP_CPU,
+		.header.len = sizeof(uvcb),
+		.cpu_handle = vcpu->arch.pv.handle,
+		.dump_area_origin = (u64)buff,
+	};
+	int cc;
+
+	cc = uv_call_sched(0, (u64)&uvcb);
+	*rc = uvcb.header.rc;
+	*rrc = uvcb.header.rrc;
+	return cc;
+}
+
+/* Size of the cache for the storage state dump data. 1MB for now */
+#define DUMP_BUFF_LEN HPAGE_SIZE
+
+/**
+ * kvm_s390_pv_dump_stor_state
+ *
+ * @kvm: pointer to the guest's KVM struct
+ * @buff_user: Userspace pointer where we will write the results to
+ * @gaddr: Starting absolute guest address for which the storage state
+ *	   is requested.
+ * @buff_user_len: Length of the buff_user buffer
+ * @rc: Pointer to where the uvcb return code is stored
+ * @rrc: Pointer to where the uvcb return reason code is stored
+ *
+ * Stores buff_len bytes of tweak component values to buff_user
+ * starting with the 1MB block specified by the absolute guest address
+ * (gaddr). The gaddr pointer will be updated with the last address
+ * for which data was written when returning to userspace. buff_user
+ * might be written to even if an error rc is returned. For instance
+ * if we encounter a fault after writing the first page of data.
+ *
+ * Context: kvm->lock needs to be held
+ *
+ * Return:
+ *  0 on success
+ *  -ENOMEM if allocating the cache fails
+ *  -EINVAL if gaddr is not aligned to 1MB
+ *  -EINVAL if buff_user_len is not aligned to uv_info.conf_dump_storage_state_len
+ *  -EINVAL if the UV call fails, rc and rrc will be set in this case
+ *  -EFAULT if copying the result to buff_user failed
+ */
+int kvm_s390_pv_dump_stor_state(struct kvm *kvm, void __user *buff_user,
+				u64 *gaddr, u64 buff_user_len, u16 *rc, u16 *rrc)
+{
+	struct uv_cb_dump_stor_state uvcb = {
+		.header.cmd = UVC_CMD_DUMP_CONF_STOR_STATE,
+		.header.len = sizeof(uvcb),
+		.config_handle = kvm->arch.pv.handle,
+		.gaddr = *gaddr,
+		.dump_area_origin = 0,
+	};
+	const u64 increment_len = uv_info.conf_dump_storage_state_len;
+	size_t buff_kvm_size;
+	size_t size_done = 0;
+	u8 *buff_kvm = NULL;
+	int cc, ret;
+
+	ret = -EINVAL;
+	/* UV call processes 1MB guest storage chunks at a time */
+	if (!IS_ALIGNED(*gaddr, HPAGE_SIZE))
+		goto out;
+
+	/*
+	 * We provide the storage state for 1MB chunks of guest
+	 * storage. The buffer will need to be aligned to
+	 * conf_dump_storage_state_len so we don't end on a partial
+	 * chunk.
+	 */
+	if (!buff_user_len ||
+	    !IS_ALIGNED(buff_user_len, increment_len))
+		goto out;
+
+	/*
+	 * Allocate a buffer from which we will later copy to the user
+	 * process. We don't want userspace to dictate our buffer size
+	 * so we limit it to DUMP_BUFF_LEN.
+	 */
+	ret = -ENOMEM;
+	buff_kvm_size = min_t(u64, buff_user_len, DUMP_BUFF_LEN);
+	buff_kvm = vzalloc(buff_kvm_size);
+	if (!buff_kvm)
+		goto out;
+
+	ret = 0;
+	uvcb.dump_area_origin = (u64)buff_kvm;
+	/* We will loop until the user buffer is filled or an error occurs */
+	do {
+		/* Get 1MB worth of guest storage state data */
+		cc = uv_call_sched(0, (u64)&uvcb);
+
+		/* All or nothing */
+		if (cc) {
+			ret = -EINVAL;
+			break;
+		}
+
+		size_done += increment_len;
+		uvcb.dump_area_origin += increment_len;
+		buff_user_len -= increment_len;
+		uvcb.gaddr += HPAGE_SIZE;
+
+		/* KVM Buffer full, time to copy to the process */
+		if (!buff_user_len || size_done == DUMP_BUFF_LEN) {
+			if (copy_to_user(buff_user, buff_kvm, size_done)) {
+				ret = -EFAULT;
+				break;
+			}
+
+			buff_user += size_done;
+			size_done = 0;
+			uvcb.dump_area_origin = (u64)buff_kvm;
+		}
+	} while (buff_user_len);
+
+	/* Report back where we ended dumping */
+	*gaddr = uvcb.gaddr;
+
+	/* Lets only log errors, we don't want to spam */
+out:
+	if (ret)
+		KVM_UV_EVENT(kvm, 3,
+			     "PROTVIRT DUMP STORAGE STATE: addr %llx ret %d, uvcb rc %x rrc %x",
+			     uvcb.gaddr, ret, uvcb.header.rc, uvcb.header.rrc);
+	*rc = uvcb.header.rc;
+	*rrc = uvcb.header.rrc;
+	vfree(buff_kvm);
+
+	return ret;
+}
+
+/**
+ * kvm_s390_pv_dump_complete
+ *
+ * @kvm: pointer to the guest's KVM struct
+ * @buff_user: Userspace pointer where we will write the results to
+ * @rc: Pointer to where the uvcb return code is stored
+ * @rrc: Pointer to where the uvcb return reason code is stored
+ *
+ * Completes the dumping operation and writes the completion data to
+ * user space.
+ *
+ * Context: kvm->lock needs to be held
+ *
+ * Return:
+ *  0 on success
+ *  -ENOMEM if allocating the completion buffer fails
+ *  -EINVAL if the UV call fails, rc and rrc will be set in this case
+ *  -EFAULT if copying the result to buff_user failed
+ */
+int kvm_s390_pv_dump_complete(struct kvm *kvm, void __user *buff_user,
+			      u16 *rc, u16 *rrc)
+{
+	struct uv_cb_dump_complete complete = {
+		.header.len = sizeof(complete),
+		.header.cmd = UVC_CMD_DUMP_COMPLETE,
+		.config_handle = kvm_s390_pv_get_handle(kvm),
+	};
+	u64 *compl_data;
+	int ret;
+
+	/* Allocate dump area */
+	compl_data = vzalloc(uv_info.conf_dump_finalize_len);
+	if (!compl_data)
+		return -ENOMEM;
+	complete.dump_area_origin = (u64)compl_data;
+
+	ret = uv_call_sched(0, (u64)&complete);
+	*rc = complete.header.rc;
+	*rrc = complete.header.rrc;
+	KVM_UV_EVENT(kvm, 3, "PROTVIRT DUMP COMPLETE: rc %x rrc %x",
+		     complete.header.rc, complete.header.rrc);
+
+	if (!ret) {
+		/*
+		 * kvm_s390_pv_dealloc_vm() will also (mem)set
+		 * this to false on a reboot or other destroy
+		 * operation for this vm.
+		 */
+		kvm->arch.pv.dumping = false;
+		kvm_s390_vcpu_unblock_all(kvm);
+		ret = copy_to_user(buff_user, compl_data, uv_info.conf_dump_finalize_len);
+		if (ret)
+			ret = -EFAULT;
+	}
+	vfree(compl_data);
+	/* If the UVC returned an error, translate it to -EINVAL */
+	if (ret > 0)
+		ret = -EINVAL;
+	return ret;
+}