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 */
25enum 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)
37static 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
43static inline enum pkvm_page_state pkvm_getstate(enum kvm_pgtable_prot prot)
44{
45	return prot & PKVM_PAGE_STATE_PROT_MASK;
46}
47
48struct 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};
54extern struct host_mmu host_mmu;
55
56/* This corresponds to page-table locking order */
57enum pkvm_component_id {
58	PKVM_ID_HOST,
59	PKVM_ID_HYP,
60	PKVM_ID_FFA,
61};
62
63extern unsigned long hyp_nr_cpus;
64
65int __pkvm_prot_finalize(void);
66int __pkvm_host_share_hyp(u64 pfn);
67int __pkvm_host_unshare_hyp(u64 pfn);
68int __pkvm_host_donate_hyp(u64 pfn, u64 nr_pages);
69int __pkvm_hyp_donate_host(u64 pfn, u64 nr_pages);
70int __pkvm_host_share_ffa(u64 pfn, u64 nr_pages);
71int __pkvm_host_unshare_ffa(u64 pfn, u64 nr_pages);
72
73bool addr_is_memory(phys_addr_t phys);
74int host_stage2_idmap_locked(phys_addr_t addr, u64 size, enum kvm_pgtable_prot prot);
75int host_stage2_set_owner_locked(phys_addr_t addr, u64 size, u8 owner_id);
76int kvm_host_prepare_stage2(void *pgt_pool_base);
77int kvm_guest_prepare_stage2(struct pkvm_hyp_vm *vm, void *pgd);
78void handle_host_mem_abort(struct kvm_cpu_context *host_ctxt);
79
80int hyp_pin_shared_mem(void *from, void *to);
81void hyp_unpin_shared_mem(void *from, void *to);
82void reclaim_guest_pages(struct pkvm_hyp_vm *vm, struct kvm_hyp_memcache *mc);
83int refill_memcache(struct kvm_hyp_memcache *mc, unsigned long min_pages,
84		    struct kvm_hyp_memcache *host_mc);
85
86static __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