1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * SPARC64 Huge TLB page support. 4 * 5 * Copyright (C) 2002, 2003, 2006 David S. Miller (davem@davemloft.net) 6 */ 7 8 #include <linux/fs.h> 9 #include <linux/mm.h> 10 #include <linux/sched/mm.h> 11 #include <linux/hugetlb.h> 12 #include <linux/pagemap.h> 13 #include <linux/sysctl.h> 14 15 #include <asm/mman.h> 16 #include <asm/pgalloc.h> 17 #include <asm/tlb.h> 18 #include <asm/tlbflush.h> 19 #include <asm/cacheflush.h> 20 #include <asm/mmu_context.h> 21 22 23 static pte_t sun4u_hugepage_shift_to_tte(pte_t entry, unsigned int shift) 24 { 25 unsigned long hugepage_size = _PAGE_SZ4MB_4U; 26 27 pte_val(entry) = pte_val(entry) & ~_PAGE_SZALL_4U; 28 29 switch (shift) { 30 case HPAGE_256MB_SHIFT: 31 hugepage_size = _PAGE_SZ256MB_4U; 32 pte_val(entry) |= _PAGE_PMD_HUGE; 33 break; 34 case HPAGE_SHIFT: 35 pte_val(entry) |= _PAGE_PMD_HUGE; 36 break; 37 case HPAGE_64K_SHIFT: 38 hugepage_size = _PAGE_SZ64K_4U; 39 break; 40 default: 41 WARN_ONCE(1, "unsupported hugepage shift=%u\n", shift); 42 } 43 44 pte_val(entry) = pte_val(entry) | hugepage_size; 45 return entry; 46 } 47 48 static pte_t sun4v_hugepage_shift_to_tte(pte_t entry, unsigned int shift) 49 { 50 unsigned long hugepage_size = _PAGE_SZ4MB_4V; 51 52 pte_val(entry) = pte_val(entry) & ~_PAGE_SZALL_4V; 53 54 switch (shift) { 55 case HPAGE_16GB_SHIFT: 56 hugepage_size = _PAGE_SZ16GB_4V; 57 pte_val(entry) |= _PAGE_PUD_HUGE; 58 break; 59 case HPAGE_2GB_SHIFT: 60 hugepage_size = _PAGE_SZ2GB_4V; 61 pte_val(entry) |= _PAGE_PMD_HUGE; 62 break; 63 case HPAGE_256MB_SHIFT: 64 hugepage_size = _PAGE_SZ256MB_4V; 65 pte_val(entry) |= _PAGE_PMD_HUGE; 66 break; 67 case HPAGE_SHIFT: 68 pte_val(entry) |= _PAGE_PMD_HUGE; 69 break; 70 case HPAGE_64K_SHIFT: 71 hugepage_size = _PAGE_SZ64K_4V; 72 break; 73 default: 74 WARN_ONCE(1, "unsupported hugepage shift=%u\n", shift); 75 } 76 77 pte_val(entry) = pte_val(entry) | hugepage_size; 78 return entry; 79 } 80 81 static pte_t hugepage_shift_to_tte(pte_t entry, unsigned int shift) 82 { 83 if (tlb_type == hypervisor) 84 return sun4v_hugepage_shift_to_tte(entry, shift); 85 else 86 return sun4u_hugepage_shift_to_tte(entry, shift); 87 } 88 89 pte_t arch_make_huge_pte(pte_t entry, unsigned int shift, vm_flags_t flags) 90 { 91 pte_t pte; 92 93 entry = pte_mkhuge(entry); 94 pte = hugepage_shift_to_tte(entry, shift); 95 96 #ifdef CONFIG_SPARC64 97 /* If this vma has ADI enabled on it, turn on TTE.mcd 98 */ 99 if (flags & VM_SPARC_ADI) 100 return pte_mkmcd(pte); 101 else 102 return pte_mknotmcd(pte); 103 #else 104 return pte; 105 #endif 106 } 107 108 static unsigned int sun4v_huge_tte_to_shift(pte_t entry) 109 { 110 unsigned long tte_szbits = pte_val(entry) & _PAGE_SZALL_4V; 111 unsigned int shift; 112 113 switch (tte_szbits) { 114 case _PAGE_SZ16GB_4V: 115 shift = HPAGE_16GB_SHIFT; 116 break; 117 case _PAGE_SZ2GB_4V: 118 shift = HPAGE_2GB_SHIFT; 119 break; 120 case _PAGE_SZ256MB_4V: 121 shift = HPAGE_256MB_SHIFT; 122 break; 123 case _PAGE_SZ4MB_4V: 124 shift = REAL_HPAGE_SHIFT; 125 break; 126 case _PAGE_SZ64K_4V: 127 shift = HPAGE_64K_SHIFT; 128 break; 129 default: 130 shift = PAGE_SHIFT; 131 break; 132 } 133 return shift; 134 } 135 136 static unsigned int sun4u_huge_tte_to_shift(pte_t entry) 137 { 138 unsigned long tte_szbits = pte_val(entry) & _PAGE_SZALL_4U; 139 unsigned int shift; 140 141 switch (tte_szbits) { 142 case _PAGE_SZ256MB_4U: 143 shift = HPAGE_256MB_SHIFT; 144 break; 145 case _PAGE_SZ4MB_4U: 146 shift = REAL_HPAGE_SHIFT; 147 break; 148 case _PAGE_SZ64K_4U: 149 shift = HPAGE_64K_SHIFT; 150 break; 151 default: 152 shift = PAGE_SHIFT; 153 break; 154 } 155 return shift; 156 } 157 158 static unsigned long tte_to_shift(pte_t entry) 159 { 160 if (tlb_type == hypervisor) 161 return sun4v_huge_tte_to_shift(entry); 162 163 return sun4u_huge_tte_to_shift(entry); 164 } 165 166 static unsigned int huge_tte_to_shift(pte_t entry) 167 { 168 unsigned long shift = tte_to_shift(entry); 169 170 if (shift == PAGE_SHIFT) 171 WARN_ONCE(1, "tto_to_shift: invalid hugepage tte=0x%lx\n", 172 pte_val(entry)); 173 174 return shift; 175 } 176 177 static unsigned long huge_tte_to_size(pte_t pte) 178 { 179 unsigned long size = 1UL << huge_tte_to_shift(pte); 180 181 if (size == REAL_HPAGE_SIZE) 182 size = HPAGE_SIZE; 183 return size; 184 } 185 186 unsigned long pud_leaf_size(pud_t pud) { return 1UL << tte_to_shift(*(pte_t *)&pud); } 187 unsigned long pmd_leaf_size(pmd_t pmd) { return 1UL << tte_to_shift(*(pte_t *)&pmd); } 188 unsigned long pte_leaf_size(pte_t pte) { return 1UL << tte_to_shift(pte); } 189 190 pte_t *huge_pte_alloc(struct mm_struct *mm, struct vm_area_struct *vma, 191 unsigned long addr, unsigned long sz) 192 { 193 pgd_t *pgd; 194 p4d_t *p4d; 195 pud_t *pud; 196 pmd_t *pmd; 197 198 pgd = pgd_offset(mm, addr); 199 p4d = p4d_offset(pgd, addr); 200 pud = pud_alloc(mm, p4d, addr); 201 if (!pud) 202 return NULL; 203 if (sz >= PUD_SIZE) 204 return (pte_t *)pud; 205 pmd = pmd_alloc(mm, pud, addr); 206 if (!pmd) 207 return NULL; 208 if (sz >= PMD_SIZE) 209 return (pte_t *)pmd; 210 return pte_alloc_huge(mm, pmd, addr); 211 } 212 213 pte_t *huge_pte_offset(struct mm_struct *mm, 214 unsigned long addr, unsigned long sz) 215 { 216 pgd_t *pgd; 217 p4d_t *p4d; 218 pud_t *pud; 219 pmd_t *pmd; 220 221 pgd = pgd_offset(mm, addr); 222 if (pgd_none(*pgd)) 223 return NULL; 224 p4d = p4d_offset(pgd, addr); 225 if (p4d_none(*p4d)) 226 return NULL; 227 pud = pud_offset(p4d, addr); 228 if (pud_none(*pud)) 229 return NULL; 230 if (is_hugetlb_pud(*pud)) 231 return (pte_t *)pud; 232 pmd = pmd_offset(pud, addr); 233 if (pmd_none(*pmd)) 234 return NULL; 235 if (is_hugetlb_pmd(*pmd)) 236 return (pte_t *)pmd; 237 return pte_offset_huge(pmd, addr); 238 } 239 240 void __set_huge_pte_at(struct mm_struct *mm, unsigned long addr, 241 pte_t *ptep, pte_t entry) 242 { 243 unsigned int nptes, orig_shift, shift; 244 unsigned long i, size; 245 pte_t orig; 246 247 size = huge_tte_to_size(entry); 248 249 shift = PAGE_SHIFT; 250 if (size >= PUD_SIZE) 251 shift = PUD_SHIFT; 252 else if (size >= PMD_SIZE) 253 shift = PMD_SHIFT; 254 else 255 shift = PAGE_SHIFT; 256 257 nptes = size >> shift; 258 259 if (!pte_present(*ptep) && pte_present(entry)) 260 mm->context.hugetlb_pte_count += nptes; 261 262 addr &= ~(size - 1); 263 orig = *ptep; 264 orig_shift = pte_none(orig) ? PAGE_SHIFT : huge_tte_to_shift(orig); 265 266 for (i = 0; i < nptes; i++) 267 ptep[i] = __pte(pte_val(entry) + (i << shift)); 268 269 maybe_tlb_batch_add(mm, addr, ptep, orig, 0, orig_shift); 270 /* An HPAGE_SIZE'ed page is composed of two REAL_HPAGE_SIZE'ed pages */ 271 if (size == HPAGE_SIZE) 272 maybe_tlb_batch_add(mm, addr + REAL_HPAGE_SIZE, ptep, orig, 0, 273 orig_shift); 274 } 275 276 void set_huge_pte_at(struct mm_struct *mm, unsigned long addr, 277 pte_t *ptep, pte_t entry, unsigned long sz) 278 { 279 __set_huge_pte_at(mm, addr, ptep, entry); 280 } 281 282 pte_t huge_ptep_get_and_clear(struct mm_struct *mm, unsigned long addr, 283 pte_t *ptep, unsigned long sz) 284 { 285 unsigned int i, nptes, orig_shift, shift; 286 unsigned long size; 287 pte_t entry; 288 289 entry = *ptep; 290 size = huge_tte_to_size(entry); 291 292 shift = PAGE_SHIFT; 293 if (size >= PUD_SIZE) 294 shift = PUD_SHIFT; 295 else if (size >= PMD_SIZE) 296 shift = PMD_SHIFT; 297 else 298 shift = PAGE_SHIFT; 299 300 nptes = size >> shift; 301 orig_shift = pte_none(entry) ? PAGE_SHIFT : huge_tte_to_shift(entry); 302 303 if (pte_present(entry)) 304 mm->context.hugetlb_pte_count -= nptes; 305 306 addr &= ~(size - 1); 307 for (i = 0; i < nptes; i++) 308 ptep[i] = __pte(0UL); 309 310 maybe_tlb_batch_add(mm, addr, ptep, entry, 0, orig_shift); 311 /* An HPAGE_SIZE'ed page is composed of two REAL_HPAGE_SIZE'ed pages */ 312 if (size == HPAGE_SIZE) 313 maybe_tlb_batch_add(mm, addr + REAL_HPAGE_SIZE, ptep, entry, 0, 314 orig_shift); 315 316 return entry; 317 } 318