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_pgt_base;
28 static struct kvm_pgtable_mm_ops pkvm_pgtable_mm_ops;
30 static int divide_memory_pool(void *virt, unsigned long size)
32 unsigned long vstart, vend, nr_pages;
34 hyp_early_alloc_init(virt, size);
36 hyp_vmemmap_range(__hyp_pa(virt), size, &vstart, &vend);
37 nr_pages = (vend - vstart) >> PAGE_SHIFT;
38 vmemmap_base = hyp_early_alloc_contig(nr_pages);
42 nr_pages = hyp_s1_pgtable_pages();
43 hyp_pgt_base = hyp_early_alloc_contig(nr_pages);
47 nr_pages = host_s2_pgtable_pages();
48 host_s2_pgt_base = hyp_early_alloc_contig(nr_pages);
49 if (!host_s2_pgt_base)
55 static int recreate_hyp_mappings(phys_addr_t phys, unsigned long size,
56 unsigned long *per_cpu_base,
59 void *start, *end, *virt = hyp_phys_to_virt(phys);
60 unsigned long pgt_size = hyp_s1_pgtable_pages() << PAGE_SHIFT;
63 /* Recreate the hyp page-table using the early page allocator */
64 hyp_early_alloc_init(hyp_pgt_base, pgt_size);
65 ret = kvm_pgtable_hyp_init(&pkvm_pgtable, hyp_va_bits,
66 &hyp_early_alloc_mm_ops);
70 ret = hyp_create_idmap(hyp_va_bits);
74 ret = hyp_map_vectors();
78 ret = hyp_back_vmemmap(phys, size, hyp_virt_to_phys(vmemmap_base));
82 ret = pkvm_create_mappings(__hyp_text_start, __hyp_text_end, PAGE_HYP_EXEC);
86 ret = pkvm_create_mappings(__start_rodata, __end_rodata, PAGE_HYP_RO);
90 ret = pkvm_create_mappings(__hyp_rodata_start, __hyp_rodata_end, PAGE_HYP_RO);
94 ret = pkvm_create_mappings(__hyp_bss_start, __hyp_bss_end, PAGE_HYP);
98 ret = pkvm_create_mappings(__hyp_bss_end, __bss_stop, PAGE_HYP_RO);
102 ret = pkvm_create_mappings(virt, virt + size, PAGE_HYP);
106 for (i = 0; i < hyp_nr_cpus; i++) {
107 start = (void *)kern_hyp_va(per_cpu_base[i]);
108 end = start + PAGE_ALIGN(hyp_percpu_size);
109 ret = pkvm_create_mappings(start, end, PAGE_HYP);
113 end = (void *)per_cpu_ptr(&kvm_init_params, i)->stack_hyp_va;
114 start = end - PAGE_SIZE;
115 ret = pkvm_create_mappings(start, end, PAGE_HYP);
123 static void update_nvhe_init_params(void)
125 struct kvm_nvhe_init_params *params;
128 for (i = 0; i < hyp_nr_cpus; i++) {
129 params = per_cpu_ptr(&kvm_init_params, i);
130 params->pgd_pa = __hyp_pa(pkvm_pgtable.pgd);
131 dcache_clean_inval_poc((unsigned long)params,
132 (unsigned long)params + sizeof(*params));
136 static void *hyp_zalloc_hyp_page(void *arg)
138 return hyp_alloc_pages(&hpool, 0);
141 static void hpool_get_page(void *addr)
143 hyp_get_page(&hpool, addr);
146 static void hpool_put_page(void *addr)
148 hyp_put_page(&hpool, addr);
151 void __noreturn __pkvm_init_finalise(void)
153 struct kvm_host_data *host_data = this_cpu_ptr(&kvm_host_data);
154 struct kvm_cpu_context *host_ctxt = &host_data->host_ctxt;
155 unsigned long nr_pages, reserved_pages, pfn;
158 /* Now that the vmemmap is backed, install the full-fledged allocator */
159 pfn = hyp_virt_to_pfn(hyp_pgt_base);
160 nr_pages = hyp_s1_pgtable_pages();
161 reserved_pages = hyp_early_alloc_nr_used_pages();
162 ret = hyp_pool_init(&hpool, pfn, nr_pages, reserved_pages);
166 ret = kvm_host_prepare_stage2(host_s2_pgt_base);
170 pkvm_pgtable_mm_ops = (struct kvm_pgtable_mm_ops) {
171 .zalloc_page = hyp_zalloc_hyp_page,
172 .phys_to_virt = hyp_phys_to_virt,
173 .virt_to_phys = hyp_virt_to_phys,
174 .get_page = hpool_get_page,
175 .put_page = hpool_put_page,
177 pkvm_pgtable.mm_ops = &pkvm_pgtable_mm_ops;
181 * We tail-called to here from handle___pkvm_init() and will not return,
182 * so make sure to propagate the return value to the host.
184 cpu_reg(host_ctxt, 1) = ret;
186 __host_enter(host_ctxt);
189 int __pkvm_init(phys_addr_t phys, unsigned long size, unsigned long nr_cpus,
190 unsigned long *per_cpu_base, u32 hyp_va_bits)
192 struct kvm_nvhe_init_params *params;
193 void *virt = hyp_phys_to_virt(phys);
194 void (*fn)(phys_addr_t params_pa, void *finalize_fn_va);
197 if (!PAGE_ALIGNED(phys) || !PAGE_ALIGNED(size))
200 hyp_spin_lock_init(&pkvm_pgd_lock);
201 hyp_nr_cpus = nr_cpus;
203 ret = divide_memory_pool(virt, size);
207 ret = recreate_hyp_mappings(phys, size, per_cpu_base, hyp_va_bits);
211 update_nvhe_init_params();
213 /* Jump in the idmap page to switch to the new page-tables */
214 params = this_cpu_ptr(&kvm_init_params);
215 fn = (typeof(fn))__hyp_pa(__pkvm_init_switch_pgd);
216 fn(__hyp_pa(params), __pkvm_init_finalise);