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_mmu.h>
12 #include <asm/kvm_pgtable.h>
13 #include <asm/virt.h>
14 #include <nvhe/pkvm.h>
15 #include <nvhe/spinlock.h>
16
17 /*
18 * SW bits 0-1 are reserved to track the memory ownership state of each page:
19 * 00: The page is owned exclusively by the page-table owner.
20 * 01: The page is owned by the page-table owner, but is shared
21 * with another entity.
22 * 10: The page is shared with, but not owned by the page-table owner.
23 * 11: Reserved for future use (lending).
24 */
25 enum pkvm_page_state {
26 PKVM_PAGE_OWNED = 0ULL,
27 PKVM_PAGE_SHARED_OWNED = KVM_PGTABLE_PROT_SW0,
28 PKVM_PAGE_SHARED_BORROWED = KVM_PGTABLE_PROT_SW1,
29 __PKVM_PAGE_RESERVED = KVM_PGTABLE_PROT_SW0 |
30 KVM_PGTABLE_PROT_SW1,
31
32 /* Meta-states which aren't encoded directly in the PTE's SW bits */
33 PKVM_NOPAGE,
34 };
35
36 #define PKVM_PAGE_STATE_PROT_MASK (KVM_PGTABLE_PROT_SW0 | KVM_PGTABLE_PROT_SW1)
37 static inline enum kvm_pgtable_prot pkvm_mkstate(enum kvm_pgtable_prot prot,
38 enum pkvm_page_state state)
39 {
40 return (prot & ~PKVM_PAGE_STATE_PROT_MASK) | state;
41 }
42
43 static inline enum pkvm_page_state pkvm_getstate(enum kvm_pgtable_prot prot)
44 {
45 return prot & PKVM_PAGE_STATE_PROT_MASK;
46 }
47
48 struct host_mmu {
49 struct kvm_arch arch;
50 struct kvm_pgtable pgt;
51 struct kvm_pgtable_mm_ops mm_ops;
52 hyp_spinlock_t lock;
53 };
54 extern struct host_mmu host_mmu;
55
56 /* This corresponds to page-table locking order */
57 enum pkvm_component_id {
58 PKVM_ID_HOST,
59 PKVM_ID_HYP,
60 PKVM_ID_FFA,
61 };
62
63 extern unsigned long hyp_nr_cpus;
64
65 int __pkvm_prot_finalize(void);
66 int __pkvm_host_share_hyp(u64 pfn);
67 int __pkvm_host_unshare_hyp(u64 pfn);
68 int __pkvm_host_donate_hyp(u64 pfn, u64 nr_pages);
69 int __pkvm_hyp_donate_host(u64 pfn, u64 nr_pages);
70 int __pkvm_host_share_ffa(u64 pfn, u64 nr_pages);
71 int __pkvm_host_unshare_ffa(u64 pfn, u64 nr_pages);
72
73 bool addr_is_memory(phys_addr_t phys);
74 int host_stage2_idmap_locked(phys_addr_t addr, u64 size, enum kvm_pgtable_prot prot);
75 int host_stage2_set_owner_locked(phys_addr_t addr, u64 size, u8 owner_id);
76 int kvm_host_prepare_stage2(void *pgt_pool_base);
77 int kvm_guest_prepare_stage2(struct pkvm_hyp_vm *vm, void *pgd);
78 void handle_host_mem_abort(struct kvm_cpu_context *host_ctxt);
79
80 int hyp_pin_shared_mem(void *from, void *to);
81 void hyp_unpin_shared_mem(void *from, void *to);
82 void reclaim_guest_pages(struct pkvm_hyp_vm *vm, struct kvm_hyp_memcache *mc);
83 int refill_memcache(struct kvm_hyp_memcache *mc, unsigned long min_pages,
84 struct kvm_hyp_memcache *host_mc);
85
86 static __always_inline void __load_host_stage2(void)
87 {
88 if (static_branch_likely(&kvm_protected_mode_initialized))
89 __load_stage2(&host_mmu.arch.mmu, &host_mmu.arch);
90 else
91 write_sysreg(0, vttbr_el2);
92 }
93 #endif /* __KVM_NVHE_MEM_PROTECT__ */
94
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