2 * Copyright (C) 2012,2013 - ARM Ltd
3 * Author: Marc Zyngier <marc.zyngier@arm.com>
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License version 2 as
7 * published by the Free Software Foundation.
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program. If not, see <http://www.gnu.org/licenses/>.
18 #ifndef __ARM64_KVM_MMU_H__
19 #define __ARM64_KVM_MMU_H__
22 #include <asm/memory.h>
25 * As we only have the TTBR0_EL2 register, we cannot express
26 * "negative" addresses. This makes it impossible to directly share
27 * mappings with the kernel.
29 * Instead, give the HYP mode its own VA region at a fixed offset from
30 * the kernel by just masking the top bits (which are all ones for a
33 #define HYP_PAGE_OFFSET_SHIFT VA_BITS
34 #define HYP_PAGE_OFFSET_MASK ((UL(1) << HYP_PAGE_OFFSET_SHIFT) - 1)
35 #define HYP_PAGE_OFFSET (PAGE_OFFSET & HYP_PAGE_OFFSET_MASK)
38 * Our virtual mapping for the idmap-ed MMU-enable code. Must be
39 * shared across all the page-tables. Conveniently, we use the last
40 * possible page, where no kernel mapping will ever exist.
42 #define TRAMPOLINE_VA (HYP_PAGE_OFFSET_MASK & PAGE_MASK)
45 * KVM_MMU_CACHE_MIN_PAGES is the number of stage2 page table translation
46 * levels in addition to the PGD and potentially the PUD which are
47 * pre-allocated (we pre-allocate the fake PGD and the PUD when the Stage-2
48 * tables use one level of tables less than the kernel.
50 #ifdef CONFIG_ARM64_64K_PAGES
51 #define KVM_MMU_CACHE_MIN_PAGES 1
53 #define KVM_MMU_CACHE_MIN_PAGES 2
59 * Convert a kernel VA into a HYP VA.
60 * reg: VA to be converted.
62 .macro kern_hyp_va reg
63 and \reg, \reg, #HYP_PAGE_OFFSET_MASK
68 #include <asm/pgalloc.h>
69 #include <asm/cachetype.h>
70 #include <asm/cacheflush.h>
72 #define KERN_TO_HYP(kva) ((unsigned long)kva - PAGE_OFFSET + HYP_PAGE_OFFSET)
75 * We currently only support a 40bit IPA.
77 #define KVM_PHYS_SHIFT (40)
78 #define KVM_PHYS_SIZE (1UL << KVM_PHYS_SHIFT)
79 #define KVM_PHYS_MASK (KVM_PHYS_SIZE - 1UL)
81 int create_hyp_mappings(void *from, void *to);
82 int create_hyp_io_mappings(void *from, void *to, phys_addr_t);
83 void free_boot_hyp_pgd(void);
84 void free_hyp_pgds(void);
86 void stage2_unmap_vm(struct kvm *kvm);
87 int kvm_alloc_stage2_pgd(struct kvm *kvm);
88 void kvm_free_stage2_pgd(struct kvm *kvm);
89 int kvm_phys_addr_ioremap(struct kvm *kvm, phys_addr_t guest_ipa,
90 phys_addr_t pa, unsigned long size, bool writable);
92 int kvm_handle_guest_abort(struct kvm_vcpu *vcpu, struct kvm_run *run);
94 void kvm_mmu_free_memory_caches(struct kvm_vcpu *vcpu);
96 phys_addr_t kvm_mmu_get_httbr(void);
97 phys_addr_t kvm_mmu_get_boot_httbr(void);
98 phys_addr_t kvm_get_idmap_vector(void);
99 int kvm_mmu_init(void);
100 void kvm_clear_hyp_idmap(void);
102 #define kvm_set_pte(ptep, pte) set_pte(ptep, pte)
103 #define kvm_set_pmd(pmdp, pmd) set_pmd(pmdp, pmd)
105 static inline void kvm_clean_pgd(pgd_t *pgd) {}
106 static inline void kvm_clean_pmd(pmd_t *pmd) {}
107 static inline void kvm_clean_pmd_entry(pmd_t *pmd) {}
108 static inline void kvm_clean_pte(pte_t *pte) {}
109 static inline void kvm_clean_pte_entry(pte_t *pte) {}
111 static inline void kvm_set_s2pte_writable(pte_t *pte)
113 pte_val(*pte) |= PTE_S2_RDWR;
116 static inline void kvm_set_s2pmd_writable(pmd_t *pmd)
118 pmd_val(*pmd) |= PMD_S2_RDWR;
121 static inline void kvm_set_s2pte_readonly(pte_t *pte)
123 pte_val(*pte) = (pte_val(*pte) & ~PTE_S2_RDWR) | PTE_S2_RDONLY;
126 static inline bool kvm_s2pte_readonly(pte_t *pte)
128 return (pte_val(*pte) & PTE_S2_RDWR) == PTE_S2_RDONLY;
131 static inline void kvm_set_s2pmd_readonly(pmd_t *pmd)
133 pmd_val(*pmd) = (pmd_val(*pmd) & ~PMD_S2_RDWR) | PMD_S2_RDONLY;
136 static inline bool kvm_s2pmd_readonly(pmd_t *pmd)
138 return (pmd_val(*pmd) & PMD_S2_RDWR) == PMD_S2_RDONLY;
142 #define kvm_pgd_addr_end(addr, end) pgd_addr_end(addr, end)
143 #define kvm_pud_addr_end(addr, end) pud_addr_end(addr, end)
144 #define kvm_pmd_addr_end(addr, end) pmd_addr_end(addr, end)
147 * In the case where PGDIR_SHIFT is larger than KVM_PHYS_SHIFT, we can address
148 * the entire IPA input range with a single pgd entry, and we would only need
149 * one pgd entry. Note that in this case, the pgd is actually not used by
150 * the MMU for Stage-2 translations, but is merely a fake pgd used as a data
151 * structure for the kernel pgtable macros to work.
153 #if PGDIR_SHIFT > KVM_PHYS_SHIFT
154 #define PTRS_PER_S2_PGD_SHIFT 0
156 #define PTRS_PER_S2_PGD_SHIFT (KVM_PHYS_SHIFT - PGDIR_SHIFT)
158 #define PTRS_PER_S2_PGD (1 << PTRS_PER_S2_PGD_SHIFT)
159 #define S2_PGD_ORDER get_order(PTRS_PER_S2_PGD * sizeof(pgd_t))
162 * If we are concatenating first level stage-2 page tables, we would have less
163 * than or equal to 16 pointers in the fake PGD, because that's what the
164 * architecture allows. In this case, (4 - CONFIG_ARM64_PGTABLE_LEVELS)
165 * represents the first level for the host, and we add 1 to go to the next
166 * level (which uses contatenation) for the stage-2 tables.
168 #if PTRS_PER_S2_PGD <= 16
169 #define KVM_PREALLOC_LEVEL (4 - CONFIG_ARM64_PGTABLE_LEVELS + 1)
171 #define KVM_PREALLOC_LEVEL (0)
175 * kvm_prealloc_hwpgd - allocate inital table for VTTBR
176 * @kvm: The KVM struct pointer for the VM.
177 * @pgd: The kernel pseudo pgd
179 * When the kernel uses more levels of page tables than the guest, we allocate
180 * a fake PGD and pre-populate it to point to the next-level page table, which
181 * will be the real initial page table pointed to by the VTTBR.
183 * When KVM_PREALLOC_LEVEL==2, we allocate a single page for the PMD and
184 * the kernel will use folded pud. When KVM_PREALLOC_LEVEL==1, we
185 * allocate 2 consecutive PUD pages.
187 static inline int kvm_prealloc_hwpgd(struct kvm *kvm, pgd_t *pgd)
192 if (KVM_PREALLOC_LEVEL == 0)
195 hwpgd = __get_free_pages(GFP_KERNEL | __GFP_ZERO, PTRS_PER_S2_PGD_SHIFT);
199 for (i = 0; i < PTRS_PER_S2_PGD; i++) {
200 if (KVM_PREALLOC_LEVEL == 1)
201 pgd_populate(NULL, pgd + i,
202 (pud_t *)hwpgd + i * PTRS_PER_PUD);
203 else if (KVM_PREALLOC_LEVEL == 2)
204 pud_populate(NULL, pud_offset(pgd, 0) + i,
205 (pmd_t *)hwpgd + i * PTRS_PER_PMD);
211 static inline void *kvm_get_hwpgd(struct kvm *kvm)
213 pgd_t *pgd = kvm->arch.pgd;
216 if (KVM_PREALLOC_LEVEL == 0)
219 pud = pud_offset(pgd, 0);
220 if (KVM_PREALLOC_LEVEL == 1)
223 BUG_ON(KVM_PREALLOC_LEVEL != 2);
224 return pmd_offset(pud, 0);
227 static inline void kvm_free_hwpgd(struct kvm *kvm)
229 if (KVM_PREALLOC_LEVEL > 0) {
230 unsigned long hwpgd = (unsigned long)kvm_get_hwpgd(kvm);
231 free_pages(hwpgd, PTRS_PER_S2_PGD_SHIFT);
235 static inline bool kvm_page_empty(void *ptr)
237 struct page *ptr_page = virt_to_page(ptr);
238 return page_count(ptr_page) == 1;
241 #define kvm_pte_table_empty(kvm, ptep) kvm_page_empty(ptep)
243 #ifdef __PAGETABLE_PMD_FOLDED
244 #define kvm_pmd_table_empty(kvm, pmdp) (0)
246 #define kvm_pmd_table_empty(kvm, pmdp) \
247 (kvm_page_empty(pmdp) && (!(kvm) || KVM_PREALLOC_LEVEL < 2))
250 #ifdef __PAGETABLE_PUD_FOLDED
251 #define kvm_pud_table_empty(kvm, pudp) (0)
253 #define kvm_pud_table_empty(kvm, pudp) \
254 (kvm_page_empty(pudp) && (!(kvm) || KVM_PREALLOC_LEVEL < 1))
260 #define kvm_flush_dcache_to_poc(a,l) __flush_dcache_area((a), (l))
262 static inline bool vcpu_has_cache_enabled(struct kvm_vcpu *vcpu)
264 return (vcpu_sys_reg(vcpu, SCTLR_EL1) & 0b101) == 0b101;
267 static inline void __coherent_cache_guest_page(struct kvm_vcpu *vcpu, pfn_t pfn,
271 void *va = page_address(pfn_to_page(pfn));
273 if (!vcpu_has_cache_enabled(vcpu) || ipa_uncached)
274 kvm_flush_dcache_to_poc(va, size);
276 if (!icache_is_aliasing()) { /* PIPT */
277 flush_icache_range((unsigned long)va,
278 (unsigned long)va + size);
279 } else if (!icache_is_aivivt()) { /* non ASID-tagged VIVT */
280 /* any kind of VIPT cache */
281 __flush_icache_all();
285 static inline void __kvm_flush_dcache_pte(pte_t pte)
287 struct page *page = pte_page(pte);
288 kvm_flush_dcache_to_poc(page_address(page), PAGE_SIZE);
291 static inline void __kvm_flush_dcache_pmd(pmd_t pmd)
293 struct page *page = pmd_page(pmd);
294 kvm_flush_dcache_to_poc(page_address(page), PMD_SIZE);
297 static inline void __kvm_flush_dcache_pud(pud_t pud)
299 struct page *page = pud_page(pud);
300 kvm_flush_dcache_to_poc(page_address(page), PUD_SIZE);
303 #define kvm_virt_to_phys(x) __virt_to_phys((unsigned long)(x))
305 void kvm_set_way_flush(struct kvm_vcpu *vcpu);
306 void kvm_toggle_cache(struct kvm_vcpu *vcpu, bool was_enabled);
308 #endif /* __ASSEMBLY__ */
309 #endif /* __ARM64_KVM_MMU_H__ */