arch/arm64/kvm/hyp/include/nvhe/mem_protect.h

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2 /*
   3  * Copyright (C) 2020 Google LLC
   4  * Author: Quentin Perret <qperret@google.com>
   5  */
   6
   7 #ifndef __KVM_NVHE_MEM_PROTECT__
   8 #define __KVM_NVHE_MEM_PROTECT__
   9 #include <linux/kvm_host.h>
  10 #include <asm/kvm_hyp.h>
  11 #include <asm/kvm_pgtable.h>
  12 #include <asm/virt.h>
  13 #include <nvhe/spinlock.h>
  14
  15 /*
  16  * SW bits 0-1 are reserved to track the memory ownership state of each page:
  17  *   00: The page is owned exclusively by the page-table owner.
  18  *   01: The page is owned by the page-table owner, but is shared
  19  *       with another entity.
  20  *   10: The page is shared with, but not owned by the page-table owner.
  21  *   11: Reserved for future use (lending).
  22  */
  23 enum pkvm_page_state {
  24         PKVM_PAGE_OWNED                 = 0ULL,
  25         PKVM_PAGE_SHARED_OWNED          = KVM_PGTABLE_PROT_SW0,
  26         PKVM_PAGE_SHARED_BORROWED       = KVM_PGTABLE_PROT_SW1,
  27 };
  28
  29 #define PKVM_PAGE_STATE_PROT_MASK       (KVM_PGTABLE_PROT_SW0 | KVM_PGTABLE_PROT_SW1)
  30 static inline enum kvm_pgtable_prot pkvm_mkstate(enum kvm_pgtable_prot prot,
  31                                                  enum pkvm_page_state state)
  32 {
  33         return (prot & ~PKVM_PAGE_STATE_PROT_MASK) | state;
  34 }
  35
  36 static inline enum pkvm_page_state pkvm_getstate(enum kvm_pgtable_prot prot)
  37 {
  38         return prot & PKVM_PAGE_STATE_PROT_MASK;
  39 }
  40
  41 struct host_kvm {
  42         struct kvm_arch arch;
  43         struct kvm_pgtable pgt;
  44         struct kvm_pgtable_mm_ops mm_ops;
  45         hyp_spinlock_t lock;
  46 };
  47 extern struct host_kvm host_kvm;
  48
  49 extern const u8 pkvm_hyp_id;
  50
  51 int __pkvm_prot_finalize(void);
  52 int __pkvm_host_share_hyp(u64 pfn);
  53
  54 bool addr_is_memory(phys_addr_t phys);
  55 int host_stage2_idmap_locked(phys_addr_t addr, u64 size, enum kvm_pgtable_prot prot);
  56 int host_stage2_set_owner_locked(phys_addr_t addr, u64 size, u8 owner_id);
  57 int kvm_host_prepare_stage2(void *pgt_pool_base);
  58 void handle_host_mem_abort(struct kvm_cpu_context *host_ctxt);
  59
  60 static __always_inline void __load_host_stage2(void)
  61 {
  62         if (static_branch_likely(&kvm_protected_mode_initialized))
  63                 __load_stage2(&host_kvm.arch.mmu, &host_kvm.arch);
  64         else
  65                 write_sysreg(0, vttbr_el2);
  66 }
  67 #endif /* __KVM_NVHE_MEM_PROTECT__ */