kvm_pkvm.h

  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * Copyright (C) 2020 - Google LLC
  4 * Author: Quentin Perret <qperret@google.com>
  5 */
  6#ifndef __ARM64_KVM_PKVM_H__
  7#define __ARM64_KVM_PKVM_H__
  8
  9#include <linux/arm_ffa.h>
 10#include <linux/memblock.h>
 11#include <linux/scatterlist.h>
 12#include <asm/kvm_pgtable.h>
 13
 14/* Maximum number of VMs that can co-exist under pKVM. */
 15#define KVM_MAX_PVMS 255
 16
 17#define HYP_MEMBLOCK_REGIONS 128
 18
 19int pkvm_init_host_vm(struct kvm *kvm);
 20int pkvm_create_hyp_vm(struct kvm *kvm);
 21bool pkvm_hyp_vm_is_created(struct kvm *kvm);
 22void pkvm_destroy_hyp_vm(struct kvm *kvm);
 23int pkvm_create_hyp_vcpu(struct kvm_vcpu *vcpu);
 24
 25/*
 26 * This functions as an allow-list of protected VM capabilities.
 27 * Features not explicitly allowed by this function are denied.
 28 */
 29static inline bool kvm_pvm_ext_allowed(long ext)
 30{
 31	switch (ext) {
 32	case KVM_CAP_IRQCHIP:
 33	case KVM_CAP_ARM_PSCI:
 34	case KVM_CAP_ARM_PSCI_0_2:
 35	case KVM_CAP_NR_VCPUS:
 36	case KVM_CAP_MAX_VCPUS:
 37	case KVM_CAP_MAX_VCPU_ID:
 38	case KVM_CAP_MSI_DEVID:
 39	case KVM_CAP_ARM_VM_IPA_SIZE:
 40	case KVM_CAP_ARM_PMU_V3:
 41	case KVM_CAP_ARM_SVE:
 42	case KVM_CAP_ARM_PTRAUTH_ADDRESS:
 43	case KVM_CAP_ARM_PTRAUTH_GENERIC:
 44		return true;
 45	default:
 46		return false;
 47	}
 48}
 49
 50extern struct memblock_region kvm_nvhe_sym(hyp_memory)[];
 51extern unsigned int kvm_nvhe_sym(hyp_memblock_nr);
 52
 53static inline unsigned long
 54hyp_vmemmap_memblock_size(struct memblock_region *reg, size_t vmemmap_entry_size)
 55{
 56	unsigned long nr_pages = reg->size >> PAGE_SHIFT;
 57	unsigned long start, end;
 58
 59	start = (reg->base >> PAGE_SHIFT) * vmemmap_entry_size;
 60	end = start + nr_pages * vmemmap_entry_size;
 61	start = ALIGN_DOWN(start, PAGE_SIZE);
 62	end = ALIGN(end, PAGE_SIZE);
 63
 64	return end - start;
 65}
 66
 67static inline unsigned long hyp_vmemmap_pages(size_t vmemmap_entry_size)
 68{
 69	unsigned long res = 0, i;
 70
 71	for (i = 0; i < kvm_nvhe_sym(hyp_memblock_nr); i++) {
 72		res += hyp_vmemmap_memblock_size(&kvm_nvhe_sym(hyp_memory)[i],
 73						 vmemmap_entry_size);
 74	}
 75
 76	return res >> PAGE_SHIFT;
 77}
 78
 79static inline unsigned long hyp_vm_table_pages(void)
 80{
 81	return PAGE_ALIGN(KVM_MAX_PVMS * sizeof(void *)) >> PAGE_SHIFT;
 82}
 83
 84static inline unsigned long __hyp_pgtable_max_pages(unsigned long nr_pages)
 85{
 86	unsigned long total = 0;
 87	int i;
 88
 89	/* Provision the worst case scenario */
 90	for (i = KVM_PGTABLE_FIRST_LEVEL; i <= KVM_PGTABLE_LAST_LEVEL; i++) {
 91		nr_pages = DIV_ROUND_UP(nr_pages, PTRS_PER_PTE);
 92		total += nr_pages;
 93	}
 94
 95	return total;
 96}
 97
 98static inline unsigned long __hyp_pgtable_total_pages(void)
 99{
100	unsigned long res = 0, i;
101
102	/* Cover all of memory with page-granularity */
103	for (i = 0; i < kvm_nvhe_sym(hyp_memblock_nr); i++) {
104		struct memblock_region *reg = &kvm_nvhe_sym(hyp_memory)[i];
105		res += __hyp_pgtable_max_pages(reg->size >> PAGE_SHIFT);
106	}
107
108	return res;
109}
110
111static inline unsigned long hyp_s1_pgtable_pages(void)
112{
113	unsigned long res;
114
115	res = __hyp_pgtable_total_pages();
116
117	/* Allow 1 GiB for private mappings */
118	res += __hyp_pgtable_max_pages(SZ_1G >> PAGE_SHIFT);
119
120	return res;
121}
122
123static inline unsigned long host_s2_pgtable_pages(void)
124{
125	unsigned long res;
126
127	/*
128	 * Include an extra 16 pages to safely upper-bound the worst case of
129	 * concatenated pgds.
130	 */
131	res = __hyp_pgtable_total_pages() + 16;
132
133	/* Allow 1 GiB for MMIO mappings */
134	res += __hyp_pgtable_max_pages(SZ_1G >> PAGE_SHIFT);
135
136	return res;
137}
138
139#ifdef CONFIG_NVHE_EL2_DEBUG
140static inline unsigned long pkvm_selftest_pages(void) { return 32; }
141#else
142static inline unsigned long pkvm_selftest_pages(void) { return 0; }
143#endif
144
145#define KVM_FFA_MBOX_NR_PAGES	1
146
147static inline unsigned long hyp_ffa_proxy_pages(void)
148{
149	size_t desc_max;
150
151	/*
152	 * The hypervisor FFA proxy needs enough memory to buffer a fragmented
153	 * descriptor returned from EL3 in response to a RETRIEVE_REQ call.
154	 */
155	desc_max = sizeof(struct ffa_mem_region) +
156		   sizeof(struct ffa_mem_region_attributes) +
157		   sizeof(struct ffa_composite_mem_region) +
158		   SG_MAX_SEGMENTS * sizeof(struct ffa_mem_region_addr_range);
159
160	/* Plus a page each for the hypervisor's RX and TX mailboxes. */
161	return (2 * KVM_FFA_MBOX_NR_PAGES) + DIV_ROUND_UP(desc_max, PAGE_SIZE);
162}
163
164static inline size_t pkvm_host_sve_state_size(void)
165{
166	if (!system_supports_sve())
167		return 0;
168
169	return size_add(sizeof(struct cpu_sve_state),
170			SVE_SIG_REGS_SIZE(sve_vq_from_vl(kvm_host_sve_max_vl)));
171}
172
173struct pkvm_mapping {
174	struct rb_node node;
175	u64 gfn;
176	u64 pfn;
177	u64 nr_pages;
178	u64 __subtree_last;	/* Internal member for interval tree */
179};
180
181int pkvm_pgtable_stage2_init(struct kvm_pgtable *pgt, struct kvm_s2_mmu *mmu,
182			     struct kvm_pgtable_mm_ops *mm_ops);
183void pkvm_pgtable_stage2_destroy_range(struct kvm_pgtable *pgt,
184					u64 addr, u64 size);
185void pkvm_pgtable_stage2_destroy_pgd(struct kvm_pgtable *pgt);
186int pkvm_pgtable_stage2_map(struct kvm_pgtable *pgt, u64 addr, u64 size, u64 phys,
187			    enum kvm_pgtable_prot prot, void *mc,
188			    enum kvm_pgtable_walk_flags flags);
189int pkvm_pgtable_stage2_unmap(struct kvm_pgtable *pgt, u64 addr, u64 size);
190int pkvm_pgtable_stage2_wrprotect(struct kvm_pgtable *pgt, u64 addr, u64 size);
191int pkvm_pgtable_stage2_flush(struct kvm_pgtable *pgt, u64 addr, u64 size);
192bool pkvm_pgtable_stage2_test_clear_young(struct kvm_pgtable *pgt, u64 addr, u64 size, bool mkold);
193int pkvm_pgtable_stage2_relax_perms(struct kvm_pgtable *pgt, u64 addr, enum kvm_pgtable_prot prot,
194				    enum kvm_pgtable_walk_flags flags);
195void pkvm_pgtable_stage2_mkyoung(struct kvm_pgtable *pgt, u64 addr,
196				 enum kvm_pgtable_walk_flags flags);
197int pkvm_pgtable_stage2_split(struct kvm_pgtable *pgt, u64 addr, u64 size,
198			      struct kvm_mmu_memory_cache *mc);
199void pkvm_pgtable_stage2_free_unlinked(struct kvm_pgtable_mm_ops *mm_ops, void *pgtable, s8 level);
200kvm_pte_t *pkvm_pgtable_stage2_create_unlinked(struct kvm_pgtable *pgt, u64 phys, s8 level,
201					       enum kvm_pgtable_prot prot, void *mc,
202					       bool force_pte);
203#endif	/* __ARM64_KVM_PKVM_H__ */