From: Fuad Tabba <tabba@xxxxxxxxxx>
Introduce a table of shadow VM structures at EL2 and provide hypercalls
to the host for creating and destroying shadow VMs.
Signed-off-by: Fuad Tabba <tabba@xxxxxxxxxx>
---
arch/arm64/include/asm/kvm_asm.h | 2 +
arch/arm64/include/asm/kvm_host.h | 6 +
arch/arm64/include/asm/kvm_pgtable.h | 8 +
arch/arm64/include/asm/kvm_pkvm.h | 8 +
arch/arm64/kvm/hyp/include/nvhe/mem_protect.h | 3 +
arch/arm64/kvm/hyp/include/nvhe/pkvm.h | 61 +++
arch/arm64/kvm/hyp/nvhe/hyp-main.c | 21 +
arch/arm64/kvm/hyp/nvhe/mem_protect.c | 14 +
arch/arm64/kvm/hyp/nvhe/pkvm.c | 398 ++++++++++++++++++
arch/arm64/kvm/hyp/nvhe/setup.c | 8 +
arch/arm64/kvm/hyp/pgtable.c | 9 +
arch/arm64/kvm/pkvm.c | 1 +
12 files changed, 539 insertions(+)
create mode 100644 arch/arm64/kvm/hyp/include/nvhe/pkvm.h
diff --git a/arch/arm64/include/asm/kvm_asm.h b/arch/arm64/include/asm/kvm_asm.h
index d5b0386ef765..f5030e88eb58 100644
--- a/arch/arm64/include/asm/kvm_asm.h
+++ b/arch/arm64/include/asm/kvm_asm.h
@@ -76,6 +76,8 @@ enum __kvm_host_smccc_func {
__KVM_HOST_SMCCC_FUNC___vgic_v3_save_aprs,
__KVM_HOST_SMCCC_FUNC___vgic_v3_restore_aprs,
__KVM_HOST_SMCCC_FUNC___pkvm_vcpu_init_traps,
+ __KVM_HOST_SMCCC_FUNC___pkvm_init_shadow,
+ __KVM_HOST_SMCCC_FUNC___pkvm_teardown_shadow,
};
#define DECLARE_KVM_VHE_SYM(sym) extern char sym[]
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index 14ed7c7ad797..9ba721fc1600 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -101,6 +101,10 @@ struct kvm_s2_mmu {
struct kvm_arch_memory_slot {
};
+struct kvm_protected_vm {
+ unsigned int shadow_handle;
+};
+
struct kvm_arch {
struct kvm_s2_mmu mmu;
@@ -140,6 +144,8 @@ struct kvm_arch {
u8 pfr0_csv2;
u8 pfr0_csv3;
+
+ struct kvm_protected_vm pkvm;
};
struct kvm_vcpu_fault_info {
diff --git a/arch/arm64/include/asm/kvm_pgtable.h b/arch/arm64/include/asm/kvm_pgtable.h
index 9f339dffbc1a..2d6b5058f7d3 100644
--- a/arch/arm64/include/asm/kvm_pgtable.h
+++ b/arch/arm64/include/asm/kvm_pgtable.h
@@ -288,6 +288,14 @@ u64 kvm_pgtable_hyp_unmap(struct kvm_pgtable *pgt, u64 addr, u64 size);
*/
u64 kvm_get_vtcr(u64 mmfr0, u64 mmfr1, u32 phys_shift);
+/*
+ * kvm_pgtable_stage2_pgd_size() - Helper to compute size of a stage-2 PGD
+ * @vtcr: Content of the VTCR register.
+ *
+ * Return: the size (in bytes) of the stage-2 PGD
+ */
+size_t kvm_pgtable_stage2_pgd_size(u64 vtcr);
+
/**
* __kvm_pgtable_stage2_init() - Initialise a guest stage-2 page-table.
* @pgt: Uninitialised page-table structure to initialise.
diff --git a/arch/arm64/include/asm/kvm_pkvm.h b/arch/arm64/include/asm/kvm_pkvm.h
index 8f7b8a2314bb..11526e89fe5c 100644
--- a/arch/arm64/include/asm/kvm_pkvm.h
+++ b/arch/arm64/include/asm/kvm_pkvm.h
@@ -9,6 +9,9 @@
#include <linux/memblock.h>
#include <asm/kvm_pgtable.h>
+/* Maximum number of protected VMs that can be created. */
+#define KVM_MAX_PVMS 255
+
#define HYP_MEMBLOCK_REGIONS 128
extern struct memblock_region kvm_nvhe_sym(hyp_memory)[];
@@ -40,6 +43,11 @@ static inline unsigned long hyp_vmemmap_pages(size_t vmemmap_entry_size)
return res >> PAGE_SHIFT;
}
+static inline unsigned long hyp_shadow_table_pages(void)
+{
+ return PAGE_ALIGN(KVM_MAX_PVMS * sizeof(void *)) >> PAGE_SHIFT;
+}
+
static inline unsigned long __hyp_pgtable_max_pages(unsigned long nr_pages)
{
unsigned long total = 0, i;
diff --git a/arch/arm64/kvm/hyp/include/nvhe/mem_protect.h b/arch/arm64/kvm/hyp/include/nvhe/mem_protect.h
index 3bea816296dc..3a0817b5c739 100644
--- a/arch/arm64/kvm/hyp/include/nvhe/mem_protect.h
+++ b/arch/arm64/kvm/hyp/include/nvhe/mem_protect.h
@@ -11,6 +11,7 @@
#include <asm/kvm_mmu.h>
#include <asm/kvm_pgtable.h>
#include <asm/virt.h>
+#include <nvhe/pkvm.h>
#include <nvhe/spinlock.h>
/*
@@ -68,10 +69,12 @@ bool addr_is_memory(phys_addr_t phys);
int host_stage2_idmap_locked(phys_addr_t addr, u64 size, enum kvm_pgtable_prot prot);
int host_stage2_set_owner_locked(phys_addr_t addr, u64 size, u8 owner_id);
int kvm_host_prepare_stage2(void *pgt_pool_base);
+int kvm_guest_prepare_stage2(struct kvm_shadow_vm *vm, void *pgd);
void handle_host_mem_abort(struct kvm_cpu_context *host_ctxt);
int hyp_pin_shared_mem(void *from, void *to);
void hyp_unpin_shared_mem(void *from, void *to);
+void reclaim_guest_pages(struct kvm_shadow_vm *vm);
static __always_inline void __load_host_stage2(void)
{
diff --git a/arch/arm64/kvm/hyp/include/nvhe/pkvm.h b/arch/arm64/kvm/hyp/include/nvhe/pkvm.h
new file mode 100644
index 000000000000..dc06b043bd83
--- /dev/null
+++ b/arch/arm64/kvm/hyp/include/nvhe/pkvm.h
@@ -0,0 +1,61 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2021 Google LLC
+ * Author: Fuad Tabba <tabba@xxxxxxxxxx>
+ */
+
+#ifndef __ARM64_KVM_NVHE_PKVM_H__
+#define __ARM64_KVM_NVHE_PKVM_H__
+
+#include <asm/kvm_pkvm.h>
+
+/*
+ * Holds the relevant data for maintaining the vcpu state completely at hyp.
+ */
+struct kvm_shadow_vcpu_state {
+ /* The data for the shadow vcpu. */
+ struct kvm_vcpu shadow_vcpu;
+
+ /* A pointer to the host's vcpu. */
+ struct kvm_vcpu *host_vcpu;
+
+ /* A pointer to the shadow vm. */
+ struct kvm_shadow_vm *shadow_vm;
+};
+
+/*
+ * Holds the relevant data for running a protected vm.
+ */
+struct kvm_shadow_vm {
+ /* The data for the shadow kvm. */
+ struct kvm kvm;
+
+ /* The host's kvm structure. */
+ struct kvm *host_kvm;
+
+ /* The total size of the donated shadow area. */
+ size_t shadow_area_size;
+
+ struct kvm_pgtable pgt;
+
+ /* Array of the shadow state per vcpu. */
+ struct kvm_shadow_vcpu_state shadow_vcpu_states[0];
+};
+
+static inline struct kvm_shadow_vcpu_state *get_shadow_state(struct kvm_vcpu *shadow_vcpu)
+{
+ return container_of(shadow_vcpu, struct kvm_shadow_vcpu_state, shadow_vcpu);
+}
+
+static inline struct kvm_shadow_vm *get_shadow_vm(struct kvm_vcpu *shadow_vcpu)
+{
+ return get_shadow_state(shadow_vcpu)->shadow_vm;
+}
+
+void hyp_shadow_table_init(void *tbl);
+int __pkvm_init_shadow(struct kvm *kvm, unsigned long shadow_hva,
+ size_t shadow_size, unsigned long pgd_hva);
+int __pkvm_teardown_shadow(unsigned int shadow_handle);
+
+#endif /* __ARM64_KVM_NVHE_PKVM_H__ */
+
diff --git a/arch/arm64/kvm/hyp/nvhe/hyp-main.c b/arch/arm64/kvm/hyp/nvhe/hyp-main.c
index 5e2197db0d32..8e51cdab00b7 100644
--- a/arch/arm64/kvm/hyp/nvhe/hyp-main.c
+++ b/arch/arm64/kvm/hyp/nvhe/hyp-main.c
@@ -15,6 +15,7 @@
#include <nvhe/mem_protect.h>
#include <nvhe/mm.h>
+#include <nvhe/pkvm.h>
#include <nvhe/trap_handler.h>
DEFINE_PER_CPU(struct kvm_nvhe_init_params, kvm_init_params);
@@ -175,6 +176,24 @@ static void handle___pkvm_vcpu_init_traps(struct kvm_cpu_context *host_ctxt)
__pkvm_vcpu_init_traps(kern_hyp_va(vcpu));
}
+static void handle___pkvm_init_shadow(struct kvm_cpu_context *host_ctxt)
+{
+ DECLARE_REG(struct kvm *, host_kvm, host_ctxt, 1);
+ DECLARE_REG(unsigned long, host_shadow_va, host_ctxt, 2);
+ DECLARE_REG(size_t, shadow_size, host_ctxt, 3);
+ DECLARE_REG(unsigned long, pgd, host_ctxt, 4);
+
+ cpu_reg(host_ctxt, 1) = __pkvm_init_shadow(host_kvm, host_shadow_va,
+ shadow_size, pgd);
+}
+
+static void handle___pkvm_teardown_shadow(struct kvm_cpu_context *host_ctxt)
+{
+ DECLARE_REG(unsigned int, shadow_handle, host_ctxt, 1);
+
+ cpu_reg(host_ctxt, 1) = __pkvm_teardown_shadow(shadow_handle);
+}
+
typedef void (*hcall_t)(struct kvm_cpu_context *);
#define HANDLE_FUNC(x) [__KVM_HOST_SMCCC_FUNC_##x] = (hcall_t)handle_##x
@@ -204,6 +223,8 @@ static const hcall_t host_hcall[] = {
HANDLE_FUNC(__vgic_v3_save_aprs),
HANDLE_FUNC(__vgic_v3_restore_aprs),
HANDLE_FUNC(__pkvm_vcpu_init_traps),
+ HANDLE_FUNC(__pkvm_init_shadow),
+ HANDLE_FUNC(__pkvm_teardown_shadow),
};
static void handle_host_hcall(struct kvm_cpu_context *host_ctxt)
diff --git a/arch/arm64/kvm/hyp/nvhe/mem_protect.c b/arch/arm64/kvm/hyp/nvhe/mem_protect.c
index 1262dbae7f06..502bc0d04858 100644
--- a/arch/arm64/kvm/hyp/nvhe/mem_protect.c
+++ b/arch/arm64/kvm/hyp/nvhe/mem_protect.c
@@ -141,6 +141,20 @@ int kvm_host_prepare_stage2(void *pgt_pool_base)
return 0;
}
+int kvm_guest_prepare_stage2(struct kvm_shadow_vm *vm, void *pgd)
+{
+ vm->pgt.pgd = pgd;
+ return 0;
+}
+
+void reclaim_guest_pages(struct kvm_shadow_vm *vm)
+{
+ unsigned long nr_pages;
+
+ nr_pages = kvm_pgtable_stage2_pgd_size(vm->kvm.arch.vtcr) >> PAGE_SHIFT;
+ WARN_ON(__pkvm_hyp_donate_host(hyp_virt_to_pfn(vm->pgt.pgd), nr_pages));
+}
+
int __pkvm_prot_finalize(void)
{
struct kvm_s2_mmu *mmu = &host_kvm.arch.mmu;
diff --git a/arch/arm64/kvm/hyp/nvhe/pkvm.c b/arch/arm64/kvm/hyp/nvhe/pkvm.c
index 99c8d8b73e70..77aeb787670b 100644
--- a/arch/arm64/kvm/hyp/nvhe/pkvm.c
+++ b/arch/arm64/kvm/hyp/nvhe/pkvm.c
@@ -7,6 +7,9 @@
#include <linux/kvm_host.h>
#include <linux/mm.h>
#include <nvhe/fixed_config.h>
+#include <nvhe/mem_protect.h>
+#include <nvhe/memory.h>
+#include <nvhe/pkvm.h>
#include <nvhe/trap_handler.h>
/*
@@ -183,3 +186,398 @@ void __pkvm_vcpu_init_traps(struct kvm_vcpu *vcpu)
pvm_init_traps_aa64mmfr0(vcpu);
pvm_init_traps_aa64mmfr1(vcpu);
}
+
+/*
+ * Start the shadow table handle at the offset defined instead of at 0.
+ * Mainly for sanity checking and debugging.
+ */
+#define HANDLE_OFFSET 0x1000
+
+static unsigned int shadow_handle_to_idx(unsigned int shadow_handle)
+{
+ return shadow_handle - HANDLE_OFFSET;
+}
+
+static unsigned int idx_to_shadow_handle(unsigned int idx)
+{
+ return idx + HANDLE_OFFSET;
+}
+
+/*
+ * Spinlock for protecting the shadow table related state.
+ * Protects writes to shadow_table, nr_shadow_entries, and next_shadow_alloc,
+ * as well as reads and writes to last_shadow_vcpu_lookup.
+ */
+static DEFINE_HYP_SPINLOCK(shadow_lock);
+
+/*
+ * The table of shadow entries for protected VMs in hyp.
+ * Allocated at hyp initialization and setup.
+ */
+static struct kvm_shadow_vm **shadow_table;
+
+/* Current number of vms in the shadow table. */
+static unsigned int nr_shadow_entries;
+
+/* The next entry index to try to allocate from. */
+static unsigned int next_shadow_alloc;
+
+void hyp_shadow_table_init(void *tbl)
+{
+ WARN_ON(shadow_table);
+ shadow_table = tbl;
+}
+
+/*
+ * Return the shadow vm corresponding to the handle.
+ */
+static struct kvm_shadow_vm *find_shadow_by_handle(unsigned int shadow_handle)
+{
+ unsigned int shadow_idx = shadow_handle_to_idx(shadow_handle);
+
+ if (unlikely(shadow_idx >= KVM_MAX_PVMS))
+ return NULL;
+
+ return shadow_table[shadow_idx];
+}
+
+static void unpin_host_vcpus(struct kvm_shadow_vcpu_state *shadow_vcpu_states,
+ unsigned int nr_vcpus)
+{
+ int i;
+
+ for (i = 0; i < nr_vcpus; i++) {
+ struct kvm_vcpu *host_vcpu = shadow_vcpu_states[i].host_vcpu;
+ hyp_unpin_shared_mem(host_vcpu, host_vcpu + 1);
+ }
+}
+
+static int set_host_vcpus(struct kvm_shadow_vcpu_state *shadow_vcpu_states,
+ unsigned int nr_vcpus,
+ struct kvm_vcpu **vcpu_array,
+ size_t vcpu_array_size)
+{
+ int i;
+
+ if (vcpu_array_size < sizeof(*vcpu_array) * nr_vcpus)
+ return -EINVAL;
+
+ for (i = 0; i < nr_vcpus; i++) {
+ struct kvm_vcpu *host_vcpu = kern_hyp_va(vcpu_array[i]);
+
+ if (hyp_pin_shared_mem(host_vcpu, host_vcpu + 1)) {
+ unpin_host_vcpus(shadow_vcpu_states, i);
+ return -EBUSY;
+ }
+
+ shadow_vcpu_states[i].host_vcpu = host_vcpu;
+ }
+
+ return 0;
+}
+
+static int init_shadow_structs(struct kvm *kvm, struct kvm_shadow_vm *vm,
+ struct kvm_vcpu **vcpu_array,
+ unsigned int nr_vcpus)
+{
+ int i;
+
+ vm->host_kvm = kvm;
+ vm->kvm.created_vcpus = nr_vcpus;
+ vm->kvm.arch.vtcr = host_kvm.arch.vtcr;
+
+ for (i = 0; i < nr_vcpus; i++) {
+ struct kvm_shadow_vcpu_state *shadow_vcpu_state = &vm->shadow_vcpu_states[i];
+ struct kvm_vcpu *shadow_vcpu = &shadow_vcpu_state->shadow_vcpu;
+ struct kvm_vcpu *host_vcpu = shadow_vcpu_state->host_vcpu;
+
+ shadow_vcpu_state->shadow_vm = vm;
+
+ shadow_vcpu->kvm = &vm->kvm;
+ shadow_vcpu->vcpu_id = READ_ONCE(host_vcpu->vcpu_id);
+ shadow_vcpu->vcpu_idx = i;
+
+ shadow_vcpu->arch.hw_mmu = &vm->kvm.arch.mmu;
+ }
+
+ return 0;
+}
+
+static bool __exists_shadow(struct kvm *host_kvm)
+{
+ int i;
+ unsigned int nr_checked = 0;
+
+ for (i = 0; i < KVM_MAX_PVMS && nr_checked < nr_shadow_entries; i++) {
+ if (!shadow_table[i])
+ continue;
+
+ if (unlikely(shadow_table[i]->host_kvm == host_kvm))
+ return true;
+
+ nr_checked++;
+ }
+
+ return false;
+}
+
+/*
+ * Allocate a shadow table entry and insert a pointer to the shadow vm.
+ *
+ * Return a unique handle to the protected VM on success,
+ * negative error code on failure.
+ */
+static unsigned int insert_shadow_table(struct kvm *kvm,
+ struct kvm_shadow_vm *vm,
+ size_t shadow_size)
+{
+ struct kvm_s2_mmu *mmu = &vm->kvm.arch.mmu;
+ unsigned int shadow_handle;
+ unsigned int vmid;
+
+ hyp_assert_lock_held(&shadow_lock);
+
+ if (unlikely(nr_shadow_entries >= KVM_MAX_PVMS))
+ return -ENOMEM;
+
+ /*
+ * Initializing protected state might have failed, yet a malicious host
+ * could trigger this function. Thus, ensure that shadow_table exists.
+ */
+ if (unlikely(!shadow_table))
+ return -EINVAL;
+
+ /* Check that a shadow hasn't been created before for this host KVM. */
+ if (unlikely(__exists_shadow(kvm)))
+ return -EEXIST;
+
+ /* Find the next free entry in the shadow table. */
+ while (shadow_table[next_shadow_alloc])
+ next_shadow_alloc = (next_shadow_alloc + 1) % KVM_MAX_PVMS;
+ shadow_handle = idx_to_shadow_handle(next_shadow_alloc);
+
+ vm->kvm.arch.pkvm.shadow_handle = shadow_handle;
+ vm->shadow_area_size = shadow_size;
+
+ /* VMID 0 is reserved for the host */
+ vmid = next_shadow_alloc + 1;
+ if (vmid > 0xff)
+ return -ENOMEM;
+
+ atomic64_set(&mmu->vmid.id, vmid);
+ mmu->arch = &vm->kvm.arch;
+ mmu->pgt = &vm->pgt;
+
+ shadow_table[next_shadow_alloc] = vm;
+ next_shadow_alloc = (next_shadow_alloc + 1) % KVM_MAX_PVMS;
+ nr_shadow_entries++;
+
+ return shadow_handle;
+}
+
+/*
+ * Deallocate and remove the shadow table entry corresponding to the handle.
+ */
+static void remove_shadow_table(unsigned int shadow_handle)
+{
+ hyp_assert_lock_held(&shadow_lock);
+ shadow_table[shadow_handle_to_idx(shadow_handle)] = NULL;
+ nr_shadow_entries--;
+}
+
+static size_t pkvm_get_shadow_size(unsigned int nr_vcpus)
+{
+ /* Shadow space for the vm struct and all of its vcpu states. */
+ return sizeof(struct kvm_shadow_vm) +
+ sizeof(struct kvm_shadow_vcpu_state) * nr_vcpus;
+}
+
+/*
+ * Check whether the size of the area donated by the host is sufficient for
+ * the shadow structures required for nr_vcpus as well as the shadow vm.
+ */
+static int check_shadow_size(unsigned int nr_vcpus, size_t shadow_size)
+{
+ if (nr_vcpus < 1 || nr_vcpus > KVM_MAX_VCPUS)
+ return -EINVAL;
+
+ /*
+ * Shadow size is rounded up when allocated and donated by the host,
+ * so it's likely to be larger than the sum of the struct sizes.
+ */
+ if (shadow_size < pkvm_get_shadow_size(nr_vcpus))
+ return -ENOMEM;
+
+ return 0;
+}
+
+static void *map_donated_memory_noclear(unsigned long host_va, size_t size)
+{
+ void *va = (void *)kern_hyp_va(host_va);
+
+ if (!PAGE_ALIGNED(va) || !PAGE_ALIGNED(size))
+ return NULL;
+
+ if (__pkvm_host_donate_hyp(hyp_virt_to_pfn(va), size >> PAGE_SHIFT))
+ return NULL;
+
+ return va;
+}
+
+static void *map_donated_memory(unsigned long host_va, size_t size)
+{
+ void *va = map_donated_memory_noclear(host_va, size);
+
+ if (va)
+ memset(va, 0, size);
+
+ return va;
+}
+
+static void __unmap_donated_memory(void *va, size_t size)
+{
+ WARN_ON(__pkvm_hyp_donate_host(hyp_virt_to_pfn(va), size >> PAGE_SHIFT));
+}
+
+static void unmap_donated_memory(void *va, size_t size)
+{
+ if (!va)
+ return;
+
+ memset(va, 0, size);
+ __unmap_donated_memory(va, size);
+}
+
+static void unmap_donated_memory_noclear(void *va, size_t size)
+{
+ if (!va)
+ return;
+
+ __unmap_donated_memory(va, size);
+}
+
+/*
+ * Initialize the shadow copy of the protected VM state using the memory
+ * donated by the host.
+ *
+ * Unmaps the donated memory from the host at stage 2.
+ *
+ * kvm: A pointer to the host's struct kvm (host va).
+ * shadow_hva: The host va of the area being donated for the shadow state.
+ * Must be page aligned.
+ * shadow_size: The size of the area being donated for the shadow state.
+ * Must be a multiple of the page size.
+ * pgd_hva: The host va of the area being donated for the stage-2 PGD for
+ * the VM. Must be page aligned. Its size is implied by the VM's
+ * VTCR.
+ * Note: An array to the host KVM VCPUs (host VA) is passed via the pgd, as to
+ * not to be dependent on how the VCPU's are layed out in struct kvm.
+ *
+ * Return a unique handle to the protected VM on success,
+ * negative error code on failure.
+ */
+int __pkvm_init_shadow(struct kvm *kvm, unsigned long shadow_hva,
+ size_t shadow_size, unsigned long pgd_hva)
+{
+ struct kvm_shadow_vm *vm = NULL;
+ unsigned int nr_vcpus;
+ size_t pgd_size = 0;
+ void *pgd = NULL;
+ int ret;
+
+ kvm = kern_hyp_va(kvm);
+ ret = hyp_pin_shared_mem(kvm, kvm + 1);
+ if (ret)
+ return ret;
+
+ nr_vcpus = READ_ONCE(kvm->created_vcpus);
+ ret = check_shadow_size(nr_vcpus, shadow_size);
+ if (ret)
+ goto err_unpin_kvm;
+
+ ret = -ENOMEM;
+
+ vm = map_donated_memory(shadow_hva, shadow_size);
+ if (!vm)
+ goto err_remove_mappings;
+
+ pgd_size = kvm_pgtable_stage2_pgd_size(host_kvm.arch.vtcr);
+ pgd = map_donated_memory_noclear(pgd_hva, pgd_size);
+ if (!pgd)
+ goto err_remove_mappings;
+
+ ret = set_host_vcpus(vm->shadow_vcpu_states, nr_vcpus, pgd, pgd_size);
+ if (ret)
+ goto err_remove_mappings;
+
+ ret = init_shadow_structs(kvm, vm, pgd, nr_vcpus);
+ if (ret < 0)
+ goto err_unpin_host_vcpus;
+
+ /* Add the entry to the shadow table. */
+ hyp_spin_lock(&shadow_lock);
+ ret = insert_shadow_table(kvm, vm, shadow_size);
+ if (ret < 0)
+ goto err_unlock_unpin_host_vcpus;
+
+ ret = kvm_guest_prepare_stage2(vm, pgd);
+ if (ret)
+ goto err_remove_shadow_table;
+ hyp_spin_unlock(&shadow_lock);
+
+ return vm->kvm.arch.pkvm.shadow_handle;
+
+err_remove_shadow_table:
+ remove_shadow_table(vm->kvm.arch.pkvm.shadow_handle);
+err_unlock_unpin_host_vcpus:
+ hyp_spin_unlock(&shadow_lock);
+err_unpin_host_vcpus:
+ unpin_host_vcpus(vm->shadow_vcpu_states, nr_vcpus);
+err_remove_mappings:
+ unmap_donated_memory(vm, shadow_size);
+ unmap_donated_memory_noclear(pgd, pgd_size);
+err_unpin_kvm:
+ hyp_unpin_shared_mem(kvm, kvm + 1);
+ return ret;
+}
+
+int __pkvm_teardown_shadow(unsigned int shadow_handle)
+{
+ struct kvm_shadow_vm *vm;
+ size_t shadow_size;
+ int err;
+
+ /* Lookup then remove entry from the shadow table. */
+ hyp_spin_lock(&shadow_lock);
+ vm = find_shadow_by_handle(shadow_handle);
+ if (!vm) {
+ err = -ENOENT;
+ goto err_unlock;
+ }
+
+ if (WARN_ON(hyp_page_count(vm))) {
+ err = -EBUSY;
+ goto err_unlock;
+ }
+
+ /* Ensure the VMID is clean before it can be reallocated */
+ __kvm_tlb_flush_vmid(&vm->kvm.arch.mmu);
+ remove_shadow_table(shadow_handle);
+ hyp_spin_unlock(&shadow_lock);
+
+ /* Reclaim guest pages (including page-table pages) */
+ reclaim_guest_pages(vm);
+ unpin_host_vcpus(vm->shadow_vcpu_states, vm->kvm.created_vcpus);
+
+ /* Push the metadata pages to the teardown memcache */
+ shadow_size = vm->shadow_area_size;
+ hyp_unpin_shared_mem(vm->host_kvm, vm->host_kvm + 1);
+
+ memset(vm, 0, shadow_size);
+ unmap_donated_memory_noclear(vm, shadow_size);
+ return 0;
+
+err_unlock:
+ hyp_spin_unlock(&shadow_lock);
+ return err;
+}
diff --git a/arch/arm64/kvm/hyp/nvhe/setup.c b/arch/arm64/kvm/hyp/nvhe/setup.c
index 311197a223e6..e9e146e50254 100644
--- a/arch/arm64/kvm/hyp/nvhe/setup.c
+++ b/arch/arm64/kvm/hyp/nvhe/setup.c
@@ -16,6 +16,7 @@
#include <nvhe/memory.h>
#include <nvhe/mem_protect.h>
#include <nvhe/mm.h>
+#include <nvhe/pkvm.h>
#include <nvhe/trap_handler.h>
unsigned long hyp_nr_cpus;
@@ -24,6 +25,7 @@ unsigned long hyp_nr_cpus;
(unsigned long)__per_cpu_start)
static void *vmemmap_base;
+static void *shadow_table_base;
static void *hyp_pgt_base;
static void *host_s2_pgt_base;
static struct kvm_pgtable_mm_ops pkvm_pgtable_mm_ops;
@@ -40,6 +42,11 @@ static int divide_memory_pool(void *virt, unsigned long size)
if (!vmemmap_base)
return -ENOMEM;
+ nr_pages = hyp_shadow_table_pages();
+ shadow_table_base = hyp_early_alloc_contig(nr_pages);
+ if (!shadow_table_base)
+ return -ENOMEM;
+
nr_pages = hyp_s1_pgtable_pages();
hyp_pgt_base = hyp_early_alloc_contig(nr_pages);
if (!hyp_pgt_base)
@@ -265,6 +272,7 @@ void __noreturn __pkvm_init_finalise(void)
if (ret)
goto out;
+ hyp_shadow_table_init(shadow_table_base);
out:
/*
* We tail-called to here from handle___pkvm_init() and will not return,
diff --git a/arch/arm64/kvm/hyp/pgtable.c b/arch/arm64/kvm/hyp/pgtable.c
index 2cb3867eb7c2..1d300313009d 100644
--- a/arch/arm64/kvm/hyp/pgtable.c
+++ b/arch/arm64/kvm/hyp/pgtable.c
@@ -1200,6 +1200,15 @@ int __kvm_pgtable_stage2_init(struct kvm_pgtable *pgt, struct kvm_s2_mmu *mmu,
return 0;
}
+size_t kvm_pgtable_stage2_pgd_size(u64 vtcr)
+{
+ u32 ia_bits = VTCR_EL2_IPA(vtcr);
+ u32 sl0 = FIELD_GET(VTCR_EL2_SL0_MASK, vtcr);
+ u32 start_level = VTCR_EL2_TGRAN_SL0_BASE - sl0;
+
+ return kvm_pgd_pages(ia_bits, start_level) * PAGE_SIZE;
+}
+
static int stage2_free_walker(u64 addr, u64 end, u32 level, kvm_pte_t *ptep,
enum kvm_pgtable_walk_flags flag,
void * const arg)
diff --git a/arch/arm64/kvm/pkvm.c b/arch/arm64/kvm/pkvm.c
index 34229425b25d..3947063cc3a1 100644
--- a/arch/arm64/kvm/pkvm.c
+++ b/arch/arm64/kvm/pkvm.c
@@ -71,6 +71,7 @@ void __init kvm_hyp_reserve(void)
hyp_mem_pages += hyp_s1_pgtable_pages();
hyp_mem_pages += host_s2_pgtable_pages();
+ hyp_mem_pages += hyp_shadow_table_pages();
hyp_mem_pages += hyp_vmemmap_pages(STRUCT_HYP_PAGE_SIZE);
/*
--
2.36.1.124.g0e6072fb45-goog
_______________________________________________
kvmarm mailing list
kvmarm@xxxxxxxxxxxxxxxxxxxxx
https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
