1 // SPDX-License-Identifier: GPL-2.0-only
3 * Copyright (C) 2020 Google LLC
4 * Author: Quentin Perret <qperret@google.com>
7 #include <linux/kvm_host.h>
8 #include <asm/kvm_hyp.h>
9 #include <asm/kvm_mmu.h>
10 #include <asm/kvm_pgtable.h>
12 #include <nvhe/early_alloc.h>
14 #include <nvhe/memory.h>
15 #include <nvhe/mem_protect.h>
17 #include <nvhe/trap_handler.h>
19 struct hyp_pool hpool;
20 unsigned long hyp_nr_cpus;
22 #define hyp_percpu_size ((unsigned long)__per_cpu_end - \
23 (unsigned long)__per_cpu_start)
25 static void *vmemmap_base;
26 static void *hyp_pgt_base;
27 static void *host_s2_mem_pgt_base;
28 static void *host_s2_dev_pgt_base;
29 static struct kvm_pgtable_mm_ops pkvm_pgtable_mm_ops;
31 static int divide_memory_pool(void *virt, unsigned long size)
33 unsigned long vstart, vend, nr_pages;
35 hyp_early_alloc_init(virt, size);
37 hyp_vmemmap_range(__hyp_pa(virt), size, &vstart, &vend);
38 nr_pages = (vend - vstart) >> PAGE_SHIFT;
39 vmemmap_base = hyp_early_alloc_contig(nr_pages);
43 nr_pages = hyp_s1_pgtable_pages();
44 hyp_pgt_base = hyp_early_alloc_contig(nr_pages);
48 nr_pages = host_s2_mem_pgtable_pages();
49 host_s2_mem_pgt_base = hyp_early_alloc_contig(nr_pages);
50 if (!host_s2_mem_pgt_base)
53 nr_pages = host_s2_dev_pgtable_pages();
54 host_s2_dev_pgt_base = hyp_early_alloc_contig(nr_pages);
55 if (!host_s2_dev_pgt_base)
61 static int recreate_hyp_mappings(phys_addr_t phys, unsigned long size,
62 unsigned long *per_cpu_base,
65 void *start, *end, *virt = hyp_phys_to_virt(phys);
66 unsigned long pgt_size = hyp_s1_pgtable_pages() << PAGE_SHIFT;
69 /* Recreate the hyp page-table using the early page allocator */
70 hyp_early_alloc_init(hyp_pgt_base, pgt_size);
71 ret = kvm_pgtable_hyp_init(&pkvm_pgtable, hyp_va_bits,
72 &hyp_early_alloc_mm_ops);
76 ret = hyp_create_idmap(hyp_va_bits);
80 ret = hyp_map_vectors();
84 ret = hyp_back_vmemmap(phys, size, hyp_virt_to_phys(vmemmap_base));
88 ret = pkvm_create_mappings(__hyp_text_start, __hyp_text_end, PAGE_HYP_EXEC);
92 ret = pkvm_create_mappings(__start_rodata, __end_rodata, PAGE_HYP_RO);
96 ret = pkvm_create_mappings(__hyp_rodata_start, __hyp_rodata_end, PAGE_HYP_RO);
100 ret = pkvm_create_mappings(__hyp_bss_start, __hyp_bss_end, PAGE_HYP);
104 ret = pkvm_create_mappings(__hyp_bss_end, __bss_stop, PAGE_HYP_RO);
108 ret = pkvm_create_mappings(virt, virt + size, PAGE_HYP);
112 for (i = 0; i < hyp_nr_cpus; i++) {
113 start = (void *)kern_hyp_va(per_cpu_base[i]);
114 end = start + PAGE_ALIGN(hyp_percpu_size);
115 ret = pkvm_create_mappings(start, end, PAGE_HYP);
119 end = (void *)per_cpu_ptr(&kvm_init_params, i)->stack_hyp_va;
120 start = end - PAGE_SIZE;
121 ret = pkvm_create_mappings(start, end, PAGE_HYP);
129 static void update_nvhe_init_params(void)
131 struct kvm_nvhe_init_params *params;
134 for (i = 0; i < hyp_nr_cpus; i++) {
135 params = per_cpu_ptr(&kvm_init_params, i);
136 params->pgd_pa = __hyp_pa(pkvm_pgtable.pgd);
137 dcache_clean_inval_poc((unsigned long)params,
138 (unsigned long)params + sizeof(*params));
142 static void *hyp_zalloc_hyp_page(void *arg)
144 return hyp_alloc_pages(&hpool, 0);
147 void __noreturn __pkvm_init_finalise(void)
149 struct kvm_host_data *host_data = this_cpu_ptr(&kvm_host_data);
150 struct kvm_cpu_context *host_ctxt = &host_data->host_ctxt;
151 unsigned long nr_pages, reserved_pages, pfn;
154 /* Now that the vmemmap is backed, install the full-fledged allocator */
155 pfn = hyp_virt_to_pfn(hyp_pgt_base);
156 nr_pages = hyp_s1_pgtable_pages();
157 reserved_pages = hyp_early_alloc_nr_used_pages();
158 ret = hyp_pool_init(&hpool, pfn, nr_pages, reserved_pages);
162 ret = kvm_host_prepare_stage2(host_s2_mem_pgt_base, host_s2_dev_pgt_base);
166 pkvm_pgtable_mm_ops = (struct kvm_pgtable_mm_ops) {
167 .zalloc_page = hyp_zalloc_hyp_page,
168 .phys_to_virt = hyp_phys_to_virt,
169 .virt_to_phys = hyp_virt_to_phys,
170 .get_page = hyp_get_page,
171 .put_page = hyp_put_page,
173 pkvm_pgtable.mm_ops = &pkvm_pgtable_mm_ops;
177 * We tail-called to here from handle___pkvm_init() and will not return,
178 * so make sure to propagate the return value to the host.
180 cpu_reg(host_ctxt, 1) = ret;
182 __host_enter(host_ctxt);
185 int __pkvm_init(phys_addr_t phys, unsigned long size, unsigned long nr_cpus,
186 unsigned long *per_cpu_base, u32 hyp_va_bits)
188 struct kvm_nvhe_init_params *params;
189 void *virt = hyp_phys_to_virt(phys);
190 void (*fn)(phys_addr_t params_pa, void *finalize_fn_va);
193 if (!PAGE_ALIGNED(phys) || !PAGE_ALIGNED(size))
196 hyp_spin_lock_init(&pkvm_pgd_lock);
197 hyp_nr_cpus = nr_cpus;
199 ret = divide_memory_pool(virt, size);
203 ret = recreate_hyp_mappings(phys, size, per_cpu_base, hyp_va_bits);
207 update_nvhe_init_params();
209 /* Jump in the idmap page to switch to the new page-tables */
210 params = this_cpu_ptr(&kvm_init_params);
211 fn = (typeof(fn))__hyp_pa(__pkvm_init_switch_pgd);
212 fn(__hyp_pa(params), __pkvm_init_finalise);