1 files changed, 73 insertions, 0 deletions
diff --git a/arch/arm64/kvm/hyp/include/nvhe/mem_protect.h b/arch/arm64/kvm/hyp/include/nvhe/mem_protect.h
new file mode 100644
index 000000000000..80e99836eac7
--- /dev/null
+++ b/arch/arm64/kvm/hyp/include/nvhe/mem_protect.h
@@ -0,0 +1,73 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2020 Google LLC
+ * Author: Quentin Perret <qperret@google.com>
+ */
+
+#ifndef __KVM_NVHE_MEM_PROTECT__
+#define __KVM_NVHE_MEM_PROTECT__
+#include <linux/kvm_host.h>
+#include <asm/kvm_hyp.h>
+#include <asm/kvm_pgtable.h>
+#include <asm/virt.h>
+#include <nvhe/spinlock.h>
+
+/*
+ * SW bits 0-1 are reserved to track the memory ownership state of each page:
+ *   00: The page is owned exclusively by the page-table owner.
+ *   01: The page is owned by the page-table owner, but is shared
+ *       with another entity.
+ *   10: The page is shared with, but not owned by the page-table owner.
+ *   11: Reserved for future use (lending).
+ */
+enum pkvm_page_state {
+	PKVM_PAGE_OWNED			= 0ULL,
+	PKVM_PAGE_SHARED_OWNED		= KVM_PGTABLE_PROT_SW0,
+	PKVM_PAGE_SHARED_BORROWED	= KVM_PGTABLE_PROT_SW1,
+	__PKVM_PAGE_RESERVED		= KVM_PGTABLE_PROT_SW0 |
+					  KVM_PGTABLE_PROT_SW1,
+
+	/* Meta-states which aren't encoded directly in the PTE's SW bits */
+	PKVM_NOPAGE,
+};
+
+#define PKVM_PAGE_STATE_PROT_MASK	(KVM_PGTABLE_PROT_SW0 | KVM_PGTABLE_PROT_SW1)
+static inline enum kvm_pgtable_prot pkvm_mkstate(enum kvm_pgtable_prot prot,
+						 enum pkvm_page_state state)
+{
+	return (prot & ~PKVM_PAGE_STATE_PROT_MASK) | state;
+}
+
+static inline enum pkvm_page_state pkvm_getstate(enum kvm_pgtable_prot prot)
+{
+	return prot & PKVM_PAGE_STATE_PROT_MASK;
+}
+
+struct host_kvm {
+	struct kvm_arch arch;
+	struct kvm_pgtable pgt;
+	struct kvm_pgtable_mm_ops mm_ops;
+	hyp_spinlock_t lock;
+};
+extern struct host_kvm host_kvm;
+
+extern const u8 pkvm_hyp_id;
+
+int __pkvm_prot_finalize(void);
+int __pkvm_host_share_hyp(u64 pfn);
+int __pkvm_host_unshare_hyp(u64 pfn);
+
+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);
+void handle_host_mem_abort(struct kvm_cpu_context *host_ctxt);
+
+static __always_inline void __load_host_stage2(void)
+{
+	if (static_branch_likely(&kvm_protected_mode_initialized))
+		__load_stage2(&host_kvm.arch.mmu, &host_kvm.arch);
+	else
+		write_sysreg(0, vttbr_el2);
+}
+#endif /* __KVM_NVHE_MEM_PROTECT__ */