| 1 | /* |
| 2 | * Copyright IBM Corp. 2007, 2011 |
| 3 | * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com> |
| 4 | */ |
| 5 | |
| 6 | #include <linux/sched.h> |
| 7 | #include <linux/kernel.h> |
| 8 | #include <linux/errno.h> |
| 9 | #include <linux/gfp.h> |
| 10 | #include <linux/mm.h> |
| 11 | #include <linux/swap.h> |
| 12 | #include <linux/smp.h> |
| 13 | #include <linux/spinlock.h> |
| 14 | #include <linux/rcupdate.h> |
| 15 | #include <linux/slab.h> |
| 16 | #include <linux/swapops.h> |
| 17 | #include <linux/sysctl.h> |
| 18 | #include <linux/ksm.h> |
| 19 | #include <linux/mman.h> |
| 20 | |
| 21 | #include <asm/pgtable.h> |
| 22 | #include <asm/pgalloc.h> |
| 23 | #include <asm/tlb.h> |
| 24 | #include <asm/tlbflush.h> |
| 25 | #include <asm/mmu_context.h> |
| 26 | #include <asm/page-states.h> |
| 27 | |
| 28 | static inline void ptep_ipte_local(struct mm_struct *mm, unsigned long addr, |
| 29 | pte_t *ptep, int nodat) |
| 30 | { |
| 31 | unsigned long opt, asce; |
| 32 | |
| 33 | if (MACHINE_HAS_TLB_GUEST) { |
| 34 | opt = 0; |
| 35 | asce = READ_ONCE(mm->context.gmap_asce); |
| 36 | if (asce == 0UL || nodat) |
| 37 | opt |= IPTE_NODAT; |
| 38 | if (asce != -1UL) { |
| 39 | asce = asce ? : mm->context.asce; |
| 40 | opt |= IPTE_GUEST_ASCE; |
| 41 | } |
| 42 | __ptep_ipte(addr, ptep, opt, asce, IPTE_LOCAL); |
| 43 | } else { |
| 44 | __ptep_ipte(addr, ptep, 0, 0, IPTE_LOCAL); |
| 45 | } |
| 46 | } |
| 47 | |
| 48 | static inline void ptep_ipte_global(struct mm_struct *mm, unsigned long addr, |
| 49 | pte_t *ptep, int nodat) |
| 50 | { |
| 51 | unsigned long opt, asce; |
| 52 | |
| 53 | if (MACHINE_HAS_TLB_GUEST) { |
| 54 | opt = 0; |
| 55 | asce = READ_ONCE(mm->context.gmap_asce); |
| 56 | if (asce == 0UL || nodat) |
| 57 | opt |= IPTE_NODAT; |
| 58 | if (asce != -1UL) { |
| 59 | asce = asce ? : mm->context.asce; |
| 60 | opt |= IPTE_GUEST_ASCE; |
| 61 | } |
| 62 | __ptep_ipte(addr, ptep, opt, asce, IPTE_GLOBAL); |
| 63 | } else { |
| 64 | __ptep_ipte(addr, ptep, 0, 0, IPTE_GLOBAL); |
| 65 | } |
| 66 | } |
| 67 | |
| 68 | static inline pte_t ptep_flush_direct(struct mm_struct *mm, |
| 69 | unsigned long addr, pte_t *ptep, |
| 70 | int nodat) |
| 71 | { |
| 72 | pte_t old; |
| 73 | |
| 74 | old = *ptep; |
| 75 | if (unlikely(pte_val(old) & _PAGE_INVALID)) |
| 76 | return old; |
| 77 | atomic_inc(&mm->context.flush_count); |
| 78 | if (MACHINE_HAS_TLB_LC && |
| 79 | cpumask_equal(mm_cpumask(mm), cpumask_of(smp_processor_id()))) |
| 80 | ptep_ipte_local(mm, addr, ptep, nodat); |
| 81 | else |
| 82 | ptep_ipte_global(mm, addr, ptep, nodat); |
| 83 | atomic_dec(&mm->context.flush_count); |
| 84 | return old; |
| 85 | } |
| 86 | |
| 87 | static inline pte_t ptep_flush_lazy(struct mm_struct *mm, |
| 88 | unsigned long addr, pte_t *ptep, |
| 89 | int nodat) |
| 90 | { |
| 91 | pte_t old; |
| 92 | |
| 93 | old = *ptep; |
| 94 | if (unlikely(pte_val(old) & _PAGE_INVALID)) |
| 95 | return old; |
| 96 | atomic_inc(&mm->context.flush_count); |
| 97 | if (cpumask_equal(&mm->context.cpu_attach_mask, |
| 98 | cpumask_of(smp_processor_id()))) { |
| 99 | pte_val(*ptep) |= _PAGE_INVALID; |
| 100 | mm->context.flush_mm = 1; |
| 101 | } else |
| 102 | ptep_ipte_global(mm, addr, ptep, nodat); |
| 103 | atomic_dec(&mm->context.flush_count); |
| 104 | return old; |
| 105 | } |
| 106 | |
| 107 | static inline pgste_t pgste_get_lock(pte_t *ptep) |
| 108 | { |
| 109 | unsigned long new = 0; |
| 110 | #ifdef CONFIG_PGSTE |
| 111 | unsigned long old; |
| 112 | |
| 113 | asm( |
| 114 | " lg %0,%2\n" |
| 115 | "0: lgr %1,%0\n" |
| 116 | " nihh %0,0xff7f\n" /* clear PCL bit in old */ |
| 117 | " oihh %1,0x0080\n" /* set PCL bit in new */ |
| 118 | " csg %0,%1,%2\n" |
| 119 | " jl 0b\n" |
| 120 | : "=&d" (old), "=&d" (new), "=Q" (ptep[PTRS_PER_PTE]) |
| 121 | : "Q" (ptep[PTRS_PER_PTE]) : "cc", "memory"); |
| 122 | #endif |
| 123 | return __pgste(new); |
| 124 | } |
| 125 | |
| 126 | static inline void pgste_set_unlock(pte_t *ptep, pgste_t pgste) |
| 127 | { |
| 128 | #ifdef CONFIG_PGSTE |
| 129 | asm( |
| 130 | " nihh %1,0xff7f\n" /* clear PCL bit */ |
| 131 | " stg %1,%0\n" |
| 132 | : "=Q" (ptep[PTRS_PER_PTE]) |
| 133 | : "d" (pgste_val(pgste)), "Q" (ptep[PTRS_PER_PTE]) |
| 134 | : "cc", "memory"); |
| 135 | #endif |
| 136 | } |
| 137 | |
| 138 | static inline pgste_t pgste_get(pte_t *ptep) |
| 139 | { |
| 140 | unsigned long pgste = 0; |
| 141 | #ifdef CONFIG_PGSTE |
| 142 | pgste = *(unsigned long *)(ptep + PTRS_PER_PTE); |
| 143 | #endif |
| 144 | return __pgste(pgste); |
| 145 | } |
| 146 | |
| 147 | static inline void pgste_set(pte_t *ptep, pgste_t pgste) |
| 148 | { |
| 149 | #ifdef CONFIG_PGSTE |
| 150 | *(pgste_t *)(ptep + PTRS_PER_PTE) = pgste; |
| 151 | #endif |
| 152 | } |
| 153 | |
| 154 | static inline pgste_t pgste_update_all(pte_t pte, pgste_t pgste, |
| 155 | struct mm_struct *mm) |
| 156 | { |
| 157 | #ifdef CONFIG_PGSTE |
| 158 | unsigned long address, bits, skey; |
| 159 | |
| 160 | if (!mm_use_skey(mm) || pte_val(pte) & _PAGE_INVALID) |
| 161 | return pgste; |
| 162 | address = pte_val(pte) & PAGE_MASK; |
| 163 | skey = (unsigned long) page_get_storage_key(address); |
| 164 | bits = skey & (_PAGE_CHANGED | _PAGE_REFERENCED); |
| 165 | /* Transfer page changed & referenced bit to guest bits in pgste */ |
| 166 | pgste_val(pgste) |= bits << 48; /* GR bit & GC bit */ |
| 167 | /* Copy page access key and fetch protection bit to pgste */ |
| 168 | pgste_val(pgste) &= ~(PGSTE_ACC_BITS | PGSTE_FP_BIT); |
| 169 | pgste_val(pgste) |= (skey & (_PAGE_ACC_BITS | _PAGE_FP_BIT)) << 56; |
| 170 | #endif |
| 171 | return pgste; |
| 172 | |
| 173 | } |
| 174 | |
| 175 | static inline void pgste_set_key(pte_t *ptep, pgste_t pgste, pte_t entry, |
| 176 | struct mm_struct *mm) |
| 177 | { |
| 178 | #ifdef CONFIG_PGSTE |
| 179 | unsigned long address; |
| 180 | unsigned long nkey; |
| 181 | |
| 182 | if (!mm_use_skey(mm) || pte_val(entry) & _PAGE_INVALID) |
| 183 | return; |
| 184 | VM_BUG_ON(!(pte_val(*ptep) & _PAGE_INVALID)); |
| 185 | address = pte_val(entry) & PAGE_MASK; |
| 186 | /* |
| 187 | * Set page access key and fetch protection bit from pgste. |
| 188 | * The guest C/R information is still in the PGSTE, set real |
| 189 | * key C/R to 0. |
| 190 | */ |
| 191 | nkey = (pgste_val(pgste) & (PGSTE_ACC_BITS | PGSTE_FP_BIT)) >> 56; |
| 192 | nkey |= (pgste_val(pgste) & (PGSTE_GR_BIT | PGSTE_GC_BIT)) >> 48; |
| 193 | page_set_storage_key(address, nkey, 0); |
| 194 | #endif |
| 195 | } |
| 196 | |
| 197 | static inline pgste_t pgste_set_pte(pte_t *ptep, pgste_t pgste, pte_t entry) |
| 198 | { |
| 199 | #ifdef CONFIG_PGSTE |
| 200 | if ((pte_val(entry) & _PAGE_PRESENT) && |
| 201 | (pte_val(entry) & _PAGE_WRITE) && |
| 202 | !(pte_val(entry) & _PAGE_INVALID)) { |
| 203 | if (!MACHINE_HAS_ESOP) { |
| 204 | /* |
| 205 | * Without enhanced suppression-on-protection force |
| 206 | * the dirty bit on for all writable ptes. |
| 207 | */ |
| 208 | pte_val(entry) |= _PAGE_DIRTY; |
| 209 | pte_val(entry) &= ~_PAGE_PROTECT; |
| 210 | } |
| 211 | if (!(pte_val(entry) & _PAGE_PROTECT)) |
| 212 | /* This pte allows write access, set user-dirty */ |
| 213 | pgste_val(pgste) |= PGSTE_UC_BIT; |
| 214 | } |
| 215 | #endif |
| 216 | *ptep = entry; |
| 217 | return pgste; |
| 218 | } |
| 219 | |
| 220 | static inline pgste_t pgste_pte_notify(struct mm_struct *mm, |
| 221 | unsigned long addr, |
| 222 | pte_t *ptep, pgste_t pgste) |
| 223 | { |
| 224 | #ifdef CONFIG_PGSTE |
| 225 | unsigned long bits; |
| 226 | |
| 227 | bits = pgste_val(pgste) & (PGSTE_IN_BIT | PGSTE_VSIE_BIT); |
| 228 | if (bits) { |
| 229 | pgste_val(pgste) ^= bits; |
| 230 | ptep_notify(mm, addr, ptep, bits); |
| 231 | } |
| 232 | #endif |
| 233 | return pgste; |
| 234 | } |
| 235 | |
| 236 | static inline pgste_t ptep_xchg_start(struct mm_struct *mm, |
| 237 | unsigned long addr, pte_t *ptep) |
| 238 | { |
| 239 | pgste_t pgste = __pgste(0); |
| 240 | |
| 241 | if (mm_has_pgste(mm)) { |
| 242 | pgste = pgste_get_lock(ptep); |
| 243 | pgste = pgste_pte_notify(mm, addr, ptep, pgste); |
| 244 | } |
| 245 | return pgste; |
| 246 | } |
| 247 | |
| 248 | static inline pte_t ptep_xchg_commit(struct mm_struct *mm, |
| 249 | unsigned long addr, pte_t *ptep, |
| 250 | pgste_t pgste, pte_t old, pte_t new) |
| 251 | { |
| 252 | if (mm_has_pgste(mm)) { |
| 253 | if (pte_val(old) & _PAGE_INVALID) |
| 254 | pgste_set_key(ptep, pgste, new, mm); |
| 255 | if (pte_val(new) & _PAGE_INVALID) { |
| 256 | pgste = pgste_update_all(old, pgste, mm); |
| 257 | if ((pgste_val(pgste) & _PGSTE_GPS_USAGE_MASK) == |
| 258 | _PGSTE_GPS_USAGE_UNUSED) |
| 259 | pte_val(old) |= _PAGE_UNUSED; |
| 260 | } |
| 261 | pgste = pgste_set_pte(ptep, pgste, new); |
| 262 | pgste_set_unlock(ptep, pgste); |
| 263 | } else { |
| 264 | *ptep = new; |
| 265 | } |
| 266 | return old; |
| 267 | } |
| 268 | |
| 269 | pte_t ptep_xchg_direct(struct mm_struct *mm, unsigned long addr, |
| 270 | pte_t *ptep, pte_t new) |
| 271 | { |
| 272 | pgste_t pgste; |
| 273 | pte_t old; |
| 274 | int nodat; |
| 275 | |
| 276 | preempt_disable(); |
| 277 | pgste = ptep_xchg_start(mm, addr, ptep); |
| 278 | nodat = !!(pgste_val(pgste) & _PGSTE_GPS_NODAT); |
| 279 | old = ptep_flush_direct(mm, addr, ptep, nodat); |
| 280 | old = ptep_xchg_commit(mm, addr, ptep, pgste, old, new); |
| 281 | preempt_enable(); |
| 282 | return old; |
| 283 | } |
| 284 | EXPORT_SYMBOL(ptep_xchg_direct); |
| 285 | |
| 286 | pte_t ptep_xchg_lazy(struct mm_struct *mm, unsigned long addr, |
| 287 | pte_t *ptep, pte_t new) |
| 288 | { |
| 289 | pgste_t pgste; |
| 290 | pte_t old; |
| 291 | int nodat; |
| 292 | |
| 293 | preempt_disable(); |
| 294 | pgste = ptep_xchg_start(mm, addr, ptep); |
| 295 | nodat = !!(pgste_val(pgste) & _PGSTE_GPS_NODAT); |
| 296 | old = ptep_flush_lazy(mm, addr, ptep, nodat); |
| 297 | old = ptep_xchg_commit(mm, addr, ptep, pgste, old, new); |
| 298 | preempt_enable(); |
| 299 | return old; |
| 300 | } |
| 301 | EXPORT_SYMBOL(ptep_xchg_lazy); |
| 302 | |
| 303 | pte_t ptep_modify_prot_start(struct mm_struct *mm, unsigned long addr, |
| 304 | pte_t *ptep) |
| 305 | { |
| 306 | pgste_t pgste; |
| 307 | pte_t old; |
| 308 | int nodat; |
| 309 | |
| 310 | preempt_disable(); |
| 311 | pgste = ptep_xchg_start(mm, addr, ptep); |
| 312 | nodat = !!(pgste_val(pgste) & _PGSTE_GPS_NODAT); |
| 313 | old = ptep_flush_lazy(mm, addr, ptep, nodat); |
| 314 | if (mm_has_pgste(mm)) { |
| 315 | pgste = pgste_update_all(old, pgste, mm); |
| 316 | pgste_set(ptep, pgste); |
| 317 | } |
| 318 | return old; |
| 319 | } |
| 320 | EXPORT_SYMBOL(ptep_modify_prot_start); |
| 321 | |
| 322 | void ptep_modify_prot_commit(struct mm_struct *mm, unsigned long addr, |
| 323 | pte_t *ptep, pte_t pte) |
| 324 | { |
| 325 | pgste_t pgste; |
| 326 | |
| 327 | if (!MACHINE_HAS_NX) |
| 328 | pte_val(pte) &= ~_PAGE_NOEXEC; |
| 329 | if (mm_has_pgste(mm)) { |
| 330 | pgste = pgste_get(ptep); |
| 331 | pgste_set_key(ptep, pgste, pte, mm); |
| 332 | pgste = pgste_set_pte(ptep, pgste, pte); |
| 333 | pgste_set_unlock(ptep, pgste); |
| 334 | } else { |
| 335 | *ptep = pte; |
| 336 | } |
| 337 | preempt_enable(); |
| 338 | } |
| 339 | EXPORT_SYMBOL(ptep_modify_prot_commit); |
| 340 | |
| 341 | static inline void pmdp_idte_local(struct mm_struct *mm, |
| 342 | unsigned long addr, pmd_t *pmdp) |
| 343 | { |
| 344 | if (MACHINE_HAS_TLB_GUEST) |
| 345 | __pmdp_idte(addr, pmdp, IDTE_NODAT | IDTE_GUEST_ASCE, |
| 346 | mm->context.asce, IDTE_LOCAL); |
| 347 | else |
| 348 | __pmdp_idte(addr, pmdp, 0, 0, IDTE_LOCAL); |
| 349 | } |
| 350 | |
| 351 | static inline void pmdp_idte_global(struct mm_struct *mm, |
| 352 | unsigned long addr, pmd_t *pmdp) |
| 353 | { |
| 354 | if (MACHINE_HAS_TLB_GUEST) |
| 355 | __pmdp_idte(addr, pmdp, IDTE_NODAT | IDTE_GUEST_ASCE, |
| 356 | mm->context.asce, IDTE_GLOBAL); |
| 357 | else if (MACHINE_HAS_IDTE) |
| 358 | __pmdp_idte(addr, pmdp, 0, 0, IDTE_GLOBAL); |
| 359 | else |
| 360 | __pmdp_csp(pmdp); |
| 361 | } |
| 362 | |
| 363 | static inline pmd_t pmdp_flush_direct(struct mm_struct *mm, |
| 364 | unsigned long addr, pmd_t *pmdp) |
| 365 | { |
| 366 | pmd_t old; |
| 367 | |
| 368 | old = *pmdp; |
| 369 | if (pmd_val(old) & _SEGMENT_ENTRY_INVALID) |
| 370 | return old; |
| 371 | atomic_inc(&mm->context.flush_count); |
| 372 | if (MACHINE_HAS_TLB_LC && |
| 373 | cpumask_equal(mm_cpumask(mm), cpumask_of(smp_processor_id()))) |
| 374 | pmdp_idte_local(mm, addr, pmdp); |
| 375 | else |
| 376 | pmdp_idte_global(mm, addr, pmdp); |
| 377 | atomic_dec(&mm->context.flush_count); |
| 378 | return old; |
| 379 | } |
| 380 | |
| 381 | static inline pmd_t pmdp_flush_lazy(struct mm_struct *mm, |
| 382 | unsigned long addr, pmd_t *pmdp) |
| 383 | { |
| 384 | pmd_t old; |
| 385 | |
| 386 | old = *pmdp; |
| 387 | if (pmd_val(old) & _SEGMENT_ENTRY_INVALID) |
| 388 | return old; |
| 389 | atomic_inc(&mm->context.flush_count); |
| 390 | if (cpumask_equal(&mm->context.cpu_attach_mask, |
| 391 | cpumask_of(smp_processor_id()))) { |
| 392 | pmd_val(*pmdp) |= _SEGMENT_ENTRY_INVALID; |
| 393 | mm->context.flush_mm = 1; |
| 394 | } else { |
| 395 | pmdp_idte_global(mm, addr, pmdp); |
| 396 | } |
| 397 | atomic_dec(&mm->context.flush_count); |
| 398 | return old; |
| 399 | } |
| 400 | |
| 401 | pmd_t pmdp_xchg_direct(struct mm_struct *mm, unsigned long addr, |
| 402 | pmd_t *pmdp, pmd_t new) |
| 403 | { |
| 404 | pmd_t old; |
| 405 | |
| 406 | preempt_disable(); |
| 407 | old = pmdp_flush_direct(mm, addr, pmdp); |
| 408 | *pmdp = new; |
| 409 | preempt_enable(); |
| 410 | return old; |
| 411 | } |
| 412 | EXPORT_SYMBOL(pmdp_xchg_direct); |
| 413 | |
| 414 | pmd_t pmdp_xchg_lazy(struct mm_struct *mm, unsigned long addr, |
| 415 | pmd_t *pmdp, pmd_t new) |
| 416 | { |
| 417 | pmd_t old; |
| 418 | |
| 419 | preempt_disable(); |
| 420 | old = pmdp_flush_lazy(mm, addr, pmdp); |
| 421 | *pmdp = new; |
| 422 | preempt_enable(); |
| 423 | return old; |
| 424 | } |
| 425 | EXPORT_SYMBOL(pmdp_xchg_lazy); |
| 426 | |
| 427 | static inline void pudp_idte_local(struct mm_struct *mm, |
| 428 | unsigned long addr, pud_t *pudp) |
| 429 | { |
| 430 | if (MACHINE_HAS_TLB_GUEST) |
| 431 | __pudp_idte(addr, pudp, IDTE_NODAT | IDTE_GUEST_ASCE, |
| 432 | mm->context.asce, IDTE_LOCAL); |
| 433 | else |
| 434 | __pudp_idte(addr, pudp, 0, 0, IDTE_LOCAL); |
| 435 | } |
| 436 | |
| 437 | static inline void pudp_idte_global(struct mm_struct *mm, |
| 438 | unsigned long addr, pud_t *pudp) |
| 439 | { |
| 440 | if (MACHINE_HAS_TLB_GUEST) |
| 441 | __pudp_idte(addr, pudp, IDTE_NODAT | IDTE_GUEST_ASCE, |
| 442 | mm->context.asce, IDTE_GLOBAL); |
| 443 | else if (MACHINE_HAS_IDTE) |
| 444 | __pudp_idte(addr, pudp, 0, 0, IDTE_GLOBAL); |
| 445 | else |
| 446 | /* |
| 447 | * Invalid bit position is the same for pmd and pud, so we can |
| 448 | * re-use _pmd_csp() here |
| 449 | */ |
| 450 | __pmdp_csp((pmd_t *) pudp); |
| 451 | } |
| 452 | |
| 453 | static inline pud_t pudp_flush_direct(struct mm_struct *mm, |
| 454 | unsigned long addr, pud_t *pudp) |
| 455 | { |
| 456 | pud_t old; |
| 457 | |
| 458 | old = *pudp; |
| 459 | if (pud_val(old) & _REGION_ENTRY_INVALID) |
| 460 | return old; |
| 461 | atomic_inc(&mm->context.flush_count); |
| 462 | if (MACHINE_HAS_TLB_LC && |
| 463 | cpumask_equal(mm_cpumask(mm), cpumask_of(smp_processor_id()))) |
| 464 | pudp_idte_local(mm, addr, pudp); |
| 465 | else |
| 466 | pudp_idte_global(mm, addr, pudp); |
| 467 | atomic_dec(&mm->context.flush_count); |
| 468 | return old; |
| 469 | } |
| 470 | |
| 471 | pud_t pudp_xchg_direct(struct mm_struct *mm, unsigned long addr, |
| 472 | pud_t *pudp, pud_t new) |
| 473 | { |
| 474 | pud_t old; |
| 475 | |
| 476 | preempt_disable(); |
| 477 | old = pudp_flush_direct(mm, addr, pudp); |
| 478 | *pudp = new; |
| 479 | preempt_enable(); |
| 480 | return old; |
| 481 | } |
| 482 | EXPORT_SYMBOL(pudp_xchg_direct); |
| 483 | |
| 484 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
| 485 | void pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp, |
| 486 | pgtable_t pgtable) |
| 487 | { |
| 488 | struct list_head *lh = (struct list_head *) pgtable; |
| 489 | |
| 490 | assert_spin_locked(pmd_lockptr(mm, pmdp)); |
| 491 | |
| 492 | /* FIFO */ |
| 493 | if (!pmd_huge_pte(mm, pmdp)) |
| 494 | INIT_LIST_HEAD(lh); |
| 495 | else |
| 496 | list_add(lh, (struct list_head *) pmd_huge_pte(mm, pmdp)); |
| 497 | pmd_huge_pte(mm, pmdp) = pgtable; |
| 498 | } |
| 499 | |
| 500 | pgtable_t pgtable_trans_huge_withdraw(struct mm_struct *mm, pmd_t *pmdp) |
| 501 | { |
| 502 | struct list_head *lh; |
| 503 | pgtable_t pgtable; |
| 504 | pte_t *ptep; |
| 505 | |
| 506 | assert_spin_locked(pmd_lockptr(mm, pmdp)); |
| 507 | |
| 508 | /* FIFO */ |
| 509 | pgtable = pmd_huge_pte(mm, pmdp); |
| 510 | lh = (struct list_head *) pgtable; |
| 511 | if (list_empty(lh)) |
| 512 | pmd_huge_pte(mm, pmdp) = NULL; |
| 513 | else { |
| 514 | pmd_huge_pte(mm, pmdp) = (pgtable_t) lh->next; |
| 515 | list_del(lh); |
| 516 | } |
| 517 | ptep = (pte_t *) pgtable; |
| 518 | pte_val(*ptep) = _PAGE_INVALID; |
| 519 | ptep++; |
| 520 | pte_val(*ptep) = _PAGE_INVALID; |
| 521 | return pgtable; |
| 522 | } |
| 523 | #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ |
| 524 | |
| 525 | #ifdef CONFIG_PGSTE |
| 526 | void ptep_set_pte_at(struct mm_struct *mm, unsigned long addr, |
| 527 | pte_t *ptep, pte_t entry) |
| 528 | { |
| 529 | pgste_t pgste; |
| 530 | |
| 531 | /* the mm_has_pgste() check is done in set_pte_at() */ |
| 532 | preempt_disable(); |
| 533 | pgste = pgste_get_lock(ptep); |
| 534 | pgste_val(pgste) &= ~_PGSTE_GPS_ZERO; |
| 535 | pgste_set_key(ptep, pgste, entry, mm); |
| 536 | pgste = pgste_set_pte(ptep, pgste, entry); |
| 537 | pgste_set_unlock(ptep, pgste); |
| 538 | preempt_enable(); |
| 539 | } |
| 540 | |
| 541 | void ptep_set_notify(struct mm_struct *mm, unsigned long addr, pte_t *ptep) |
| 542 | { |
| 543 | pgste_t pgste; |
| 544 | |
| 545 | preempt_disable(); |
| 546 | pgste = pgste_get_lock(ptep); |
| 547 | pgste_val(pgste) |= PGSTE_IN_BIT; |
| 548 | pgste_set_unlock(ptep, pgste); |
| 549 | preempt_enable(); |
| 550 | } |
| 551 | |
| 552 | /** |
| 553 | * ptep_force_prot - change access rights of a locked pte |
| 554 | * @mm: pointer to the process mm_struct |
| 555 | * @addr: virtual address in the guest address space |
| 556 | * @ptep: pointer to the page table entry |
| 557 | * @prot: indicates guest access rights: PROT_NONE, PROT_READ or PROT_WRITE |
| 558 | * @bit: pgste bit to set (e.g. for notification) |
| 559 | * |
| 560 | * Returns 0 if the access rights were changed and -EAGAIN if the current |
| 561 | * and requested access rights are incompatible. |
| 562 | */ |
| 563 | int ptep_force_prot(struct mm_struct *mm, unsigned long addr, |
| 564 | pte_t *ptep, int prot, unsigned long bit) |
| 565 | { |
| 566 | pte_t entry; |
| 567 | pgste_t pgste; |
| 568 | int pte_i, pte_p, nodat; |
| 569 | |
| 570 | pgste = pgste_get_lock(ptep); |
| 571 | entry = *ptep; |
| 572 | /* Check pte entry after all locks have been acquired */ |
| 573 | pte_i = pte_val(entry) & _PAGE_INVALID; |
| 574 | pte_p = pte_val(entry) & _PAGE_PROTECT; |
| 575 | if ((pte_i && (prot != PROT_NONE)) || |
| 576 | (pte_p && (prot & PROT_WRITE))) { |
| 577 | pgste_set_unlock(ptep, pgste); |
| 578 | return -EAGAIN; |
| 579 | } |
| 580 | /* Change access rights and set pgste bit */ |
| 581 | nodat = !!(pgste_val(pgste) & _PGSTE_GPS_NODAT); |
| 582 | if (prot == PROT_NONE && !pte_i) { |
| 583 | ptep_flush_direct(mm, addr, ptep, nodat); |
| 584 | pgste = pgste_update_all(entry, pgste, mm); |
| 585 | pte_val(entry) |= _PAGE_INVALID; |
| 586 | } |
| 587 | if (prot == PROT_READ && !pte_p) { |
| 588 | ptep_flush_direct(mm, addr, ptep, nodat); |
| 589 | pte_val(entry) &= ~_PAGE_INVALID; |
| 590 | pte_val(entry) |= _PAGE_PROTECT; |
| 591 | } |
| 592 | pgste_val(pgste) |= bit; |
| 593 | pgste = pgste_set_pte(ptep, pgste, entry); |
| 594 | pgste_set_unlock(ptep, pgste); |
| 595 | return 0; |
| 596 | } |
| 597 | |
| 598 | int ptep_shadow_pte(struct mm_struct *mm, unsigned long saddr, |
| 599 | pte_t *sptep, pte_t *tptep, pte_t pte) |
| 600 | { |
| 601 | pgste_t spgste, tpgste; |
| 602 | pte_t spte, tpte; |
| 603 | int rc = -EAGAIN; |
| 604 | |
| 605 | if (!(pte_val(*tptep) & _PAGE_INVALID)) |
| 606 | return 0; /* already shadowed */ |
| 607 | spgste = pgste_get_lock(sptep); |
| 608 | spte = *sptep; |
| 609 | if (!(pte_val(spte) & _PAGE_INVALID) && |
| 610 | !((pte_val(spte) & _PAGE_PROTECT) && |
| 611 | !(pte_val(pte) & _PAGE_PROTECT))) { |
| 612 | pgste_val(spgste) |= PGSTE_VSIE_BIT; |
| 613 | tpgste = pgste_get_lock(tptep); |
| 614 | pte_val(tpte) = (pte_val(spte) & PAGE_MASK) | |
| 615 | (pte_val(pte) & _PAGE_PROTECT); |
| 616 | /* don't touch the storage key - it belongs to parent pgste */ |
| 617 | tpgste = pgste_set_pte(tptep, tpgste, tpte); |
| 618 | pgste_set_unlock(tptep, tpgste); |
| 619 | rc = 1; |
| 620 | } |
| 621 | pgste_set_unlock(sptep, spgste); |
| 622 | return rc; |
| 623 | } |
| 624 | |
| 625 | void ptep_unshadow_pte(struct mm_struct *mm, unsigned long saddr, pte_t *ptep) |
| 626 | { |
| 627 | pgste_t pgste; |
| 628 | int nodat; |
| 629 | |
| 630 | pgste = pgste_get_lock(ptep); |
| 631 | /* notifier is called by the caller */ |
| 632 | nodat = !!(pgste_val(pgste) & _PGSTE_GPS_NODAT); |
| 633 | ptep_flush_direct(mm, saddr, ptep, nodat); |
| 634 | /* don't touch the storage key - it belongs to parent pgste */ |
| 635 | pgste = pgste_set_pte(ptep, pgste, __pte(_PAGE_INVALID)); |
| 636 | pgste_set_unlock(ptep, pgste); |
| 637 | } |
| 638 | |
| 639 | static void ptep_zap_swap_entry(struct mm_struct *mm, swp_entry_t entry) |
| 640 | { |
| 641 | if (!non_swap_entry(entry)) |
| 642 | dec_mm_counter(mm, MM_SWAPENTS); |
| 643 | else if (is_migration_entry(entry)) { |
| 644 | struct page *page = migration_entry_to_page(entry); |
| 645 | |
| 646 | dec_mm_counter(mm, mm_counter(page)); |
| 647 | } |
| 648 | free_swap_and_cache(entry); |
| 649 | } |
| 650 | |
| 651 | void ptep_zap_unused(struct mm_struct *mm, unsigned long addr, |
| 652 | pte_t *ptep, int reset) |
| 653 | { |
| 654 | unsigned long pgstev; |
| 655 | pgste_t pgste; |
| 656 | pte_t pte; |
| 657 | |
| 658 | /* Zap unused and logically-zero pages */ |
| 659 | preempt_disable(); |
| 660 | pgste = pgste_get_lock(ptep); |
| 661 | pgstev = pgste_val(pgste); |
| 662 | pte = *ptep; |
| 663 | if (!reset && pte_swap(pte) && |
| 664 | ((pgstev & _PGSTE_GPS_USAGE_MASK) == _PGSTE_GPS_USAGE_UNUSED || |
| 665 | (pgstev & _PGSTE_GPS_ZERO))) { |
| 666 | ptep_zap_swap_entry(mm, pte_to_swp_entry(pte)); |
| 667 | pte_clear(mm, addr, ptep); |
| 668 | } |
| 669 | if (reset) |
| 670 | pgste_val(pgste) &= ~_PGSTE_GPS_USAGE_MASK; |
| 671 | pgste_set_unlock(ptep, pgste); |
| 672 | preempt_enable(); |
| 673 | } |
| 674 | |
| 675 | void ptep_zap_key(struct mm_struct *mm, unsigned long addr, pte_t *ptep) |
| 676 | { |
| 677 | unsigned long ptev; |
| 678 | pgste_t pgste; |
| 679 | |
| 680 | /* Clear storage key ACC and F, but set R/C */ |
| 681 | preempt_disable(); |
| 682 | pgste = pgste_get_lock(ptep); |
| 683 | pgste_val(pgste) &= ~(PGSTE_ACC_BITS | PGSTE_FP_BIT); |
| 684 | pgste_val(pgste) |= PGSTE_GR_BIT | PGSTE_GC_BIT; |
| 685 | ptev = pte_val(*ptep); |
| 686 | if (!(ptev & _PAGE_INVALID) && (ptev & _PAGE_WRITE)) |
| 687 | page_set_storage_key(ptev & PAGE_MASK, PAGE_DEFAULT_KEY, 1); |
| 688 | pgste_set_unlock(ptep, pgste); |
| 689 | preempt_enable(); |
| 690 | } |
| 691 | |
| 692 | /* |
| 693 | * Test and reset if a guest page is dirty |
| 694 | */ |
| 695 | bool test_and_clear_guest_dirty(struct mm_struct *mm, unsigned long addr) |
| 696 | { |
| 697 | spinlock_t *ptl; |
| 698 | pgd_t *pgd; |
| 699 | p4d_t *p4d; |
| 700 | pud_t *pud; |
| 701 | pmd_t *pmd; |
| 702 | pgste_t pgste; |
| 703 | pte_t *ptep; |
| 704 | pte_t pte; |
| 705 | bool dirty; |
| 706 | int nodat; |
| 707 | |
| 708 | pgd = pgd_offset(mm, addr); |
| 709 | p4d = p4d_alloc(mm, pgd, addr); |
| 710 | if (!p4d) |
| 711 | return false; |
| 712 | pud = pud_alloc(mm, p4d, addr); |
| 713 | if (!pud) |
| 714 | return false; |
| 715 | pmd = pmd_alloc(mm, pud, addr); |
| 716 | if (!pmd) |
| 717 | return false; |
| 718 | /* We can't run guests backed by huge pages, but userspace can |
| 719 | * still set them up and then try to migrate them without any |
| 720 | * migration support. |
| 721 | */ |
| 722 | if (pmd_large(*pmd)) |
| 723 | return true; |
| 724 | |
| 725 | ptep = pte_alloc_map_lock(mm, pmd, addr, &ptl); |
| 726 | if (unlikely(!ptep)) |
| 727 | return false; |
| 728 | |
| 729 | pgste = pgste_get_lock(ptep); |
| 730 | dirty = !!(pgste_val(pgste) & PGSTE_UC_BIT); |
| 731 | pgste_val(pgste) &= ~PGSTE_UC_BIT; |
| 732 | pte = *ptep; |
| 733 | if (dirty && (pte_val(pte) & _PAGE_PRESENT)) { |
| 734 | pgste = pgste_pte_notify(mm, addr, ptep, pgste); |
| 735 | nodat = !!(pgste_val(pgste) & _PGSTE_GPS_NODAT); |
| 736 | ptep_ipte_global(mm, addr, ptep, nodat); |
| 737 | if (MACHINE_HAS_ESOP || !(pte_val(pte) & _PAGE_WRITE)) |
| 738 | pte_val(pte) |= _PAGE_PROTECT; |
| 739 | else |
| 740 | pte_val(pte) |= _PAGE_INVALID; |
| 741 | *ptep = pte; |
| 742 | } |
| 743 | pgste_set_unlock(ptep, pgste); |
| 744 | |
| 745 | spin_unlock(ptl); |
| 746 | return dirty; |
| 747 | } |
| 748 | EXPORT_SYMBOL_GPL(test_and_clear_guest_dirty); |
| 749 | |
| 750 | int set_guest_storage_key(struct mm_struct *mm, unsigned long addr, |
| 751 | unsigned char key, bool nq) |
| 752 | { |
| 753 | unsigned long keyul; |
| 754 | spinlock_t *ptl; |
| 755 | pgste_t old, new; |
| 756 | pte_t *ptep; |
| 757 | |
| 758 | ptep = get_locked_pte(mm, addr, &ptl); |
| 759 | if (unlikely(!ptep)) |
| 760 | return -EFAULT; |
| 761 | |
| 762 | new = old = pgste_get_lock(ptep); |
| 763 | pgste_val(new) &= ~(PGSTE_GR_BIT | PGSTE_GC_BIT | |
| 764 | PGSTE_ACC_BITS | PGSTE_FP_BIT); |
| 765 | keyul = (unsigned long) key; |
| 766 | pgste_val(new) |= (keyul & (_PAGE_CHANGED | _PAGE_REFERENCED)) << 48; |
| 767 | pgste_val(new) |= (keyul & (_PAGE_ACC_BITS | _PAGE_FP_BIT)) << 56; |
| 768 | if (!(pte_val(*ptep) & _PAGE_INVALID)) { |
| 769 | unsigned long address, bits, skey; |
| 770 | |
| 771 | address = pte_val(*ptep) & PAGE_MASK; |
| 772 | skey = (unsigned long) page_get_storage_key(address); |
| 773 | bits = skey & (_PAGE_CHANGED | _PAGE_REFERENCED); |
| 774 | skey = key & (_PAGE_ACC_BITS | _PAGE_FP_BIT); |
| 775 | /* Set storage key ACC and FP */ |
| 776 | page_set_storage_key(address, skey, !nq); |
| 777 | /* Merge host changed & referenced into pgste */ |
| 778 | pgste_val(new) |= bits << 52; |
| 779 | } |
| 780 | /* changing the guest storage key is considered a change of the page */ |
| 781 | if ((pgste_val(new) ^ pgste_val(old)) & |
| 782 | (PGSTE_ACC_BITS | PGSTE_FP_BIT | PGSTE_GR_BIT | PGSTE_GC_BIT)) |
| 783 | pgste_val(new) |= PGSTE_UC_BIT; |
| 784 | |
| 785 | pgste_set_unlock(ptep, new); |
| 786 | pte_unmap_unlock(ptep, ptl); |
| 787 | return 0; |
| 788 | } |
| 789 | EXPORT_SYMBOL(set_guest_storage_key); |
| 790 | |
| 791 | /** |
| 792 | * Conditionally set a guest storage key (handling csske). |
| 793 | * oldkey will be updated when either mr or mc is set and a pointer is given. |
| 794 | * |
| 795 | * Returns 0 if a guests storage key update wasn't necessary, 1 if the guest |
| 796 | * storage key was updated and -EFAULT on access errors. |
| 797 | */ |
| 798 | int cond_set_guest_storage_key(struct mm_struct *mm, unsigned long addr, |
| 799 | unsigned char key, unsigned char *oldkey, |
| 800 | bool nq, bool mr, bool mc) |
| 801 | { |
| 802 | unsigned char tmp, mask = _PAGE_ACC_BITS | _PAGE_FP_BIT; |
| 803 | int rc; |
| 804 | |
| 805 | /* we can drop the pgste lock between getting and setting the key */ |
| 806 | if (mr | mc) { |
| 807 | rc = get_guest_storage_key(current->mm, addr, &tmp); |
| 808 | if (rc) |
| 809 | return rc; |
| 810 | if (oldkey) |
| 811 | *oldkey = tmp; |
| 812 | if (!mr) |
| 813 | mask |= _PAGE_REFERENCED; |
| 814 | if (!mc) |
| 815 | mask |= _PAGE_CHANGED; |
| 816 | if (!((tmp ^ key) & mask)) |
| 817 | return 0; |
| 818 | } |
| 819 | rc = set_guest_storage_key(current->mm, addr, key, nq); |
| 820 | return rc < 0 ? rc : 1; |
| 821 | } |
| 822 | EXPORT_SYMBOL(cond_set_guest_storage_key); |
| 823 | |
| 824 | /** |
| 825 | * Reset a guest reference bit (rrbe), returning the reference and changed bit. |
| 826 | * |
| 827 | * Returns < 0 in case of error, otherwise the cc to be reported to the guest. |
| 828 | */ |
| 829 | int reset_guest_reference_bit(struct mm_struct *mm, unsigned long addr) |
| 830 | { |
| 831 | spinlock_t *ptl; |
| 832 | pgste_t old, new; |
| 833 | pte_t *ptep; |
| 834 | int cc = 0; |
| 835 | |
| 836 | ptep = get_locked_pte(mm, addr, &ptl); |
| 837 | if (unlikely(!ptep)) |
| 838 | return -EFAULT; |
| 839 | |
| 840 | new = old = pgste_get_lock(ptep); |
| 841 | /* Reset guest reference bit only */ |
| 842 | pgste_val(new) &= ~PGSTE_GR_BIT; |
| 843 | |
| 844 | if (!(pte_val(*ptep) & _PAGE_INVALID)) { |
| 845 | cc = page_reset_referenced(pte_val(*ptep) & PAGE_MASK); |
| 846 | /* Merge real referenced bit into host-set */ |
| 847 | pgste_val(new) |= ((unsigned long) cc << 53) & PGSTE_HR_BIT; |
| 848 | } |
| 849 | /* Reflect guest's logical view, not physical */ |
| 850 | cc |= (pgste_val(old) & (PGSTE_GR_BIT | PGSTE_GC_BIT)) >> 49; |
| 851 | /* Changing the guest storage key is considered a change of the page */ |
| 852 | if ((pgste_val(new) ^ pgste_val(old)) & PGSTE_GR_BIT) |
| 853 | pgste_val(new) |= PGSTE_UC_BIT; |
| 854 | |
| 855 | pgste_set_unlock(ptep, new); |
| 856 | pte_unmap_unlock(ptep, ptl); |
| 857 | return cc; |
| 858 | } |
| 859 | EXPORT_SYMBOL(reset_guest_reference_bit); |
| 860 | |
| 861 | int get_guest_storage_key(struct mm_struct *mm, unsigned long addr, |
| 862 | unsigned char *key) |
| 863 | { |
| 864 | spinlock_t *ptl; |
| 865 | pgste_t pgste; |
| 866 | pte_t *ptep; |
| 867 | |
| 868 | ptep = get_locked_pte(mm, addr, &ptl); |
| 869 | if (unlikely(!ptep)) |
| 870 | return -EFAULT; |
| 871 | |
| 872 | pgste = pgste_get_lock(ptep); |
| 873 | *key = (pgste_val(pgste) & (PGSTE_ACC_BITS | PGSTE_FP_BIT)) >> 56; |
| 874 | if (!(pte_val(*ptep) & _PAGE_INVALID)) |
| 875 | *key = page_get_storage_key(pte_val(*ptep) & PAGE_MASK); |
| 876 | /* Reflect guest's logical view, not physical */ |
| 877 | *key |= (pgste_val(pgste) & (PGSTE_GR_BIT | PGSTE_GC_BIT)) >> 48; |
| 878 | pgste_set_unlock(ptep, pgste); |
| 879 | pte_unmap_unlock(ptep, ptl); |
| 880 | return 0; |
| 881 | } |
| 882 | EXPORT_SYMBOL(get_guest_storage_key); |
| 883 | |
| 884 | /** |
| 885 | * pgste_perform_essa - perform ESSA actions on the PGSTE. |
| 886 | * @mm: the memory context. It must have PGSTEs, no check is performed here! |
| 887 | * @hva: the host virtual address of the page whose PGSTE is to be processed |
| 888 | * @orc: the specific action to perform, see the ESSA_SET_* macros. |
| 889 | * @oldpte: the PTE will be saved there if the pointer is not NULL. |
| 890 | * @oldpgste: the old PGSTE will be saved there if the pointer is not NULL. |
| 891 | * |
| 892 | * Return: 1 if the page is to be added to the CBRL, otherwise 0, |
| 893 | * or < 0 in case of error. -EINVAL is returned for invalid values |
| 894 | * of orc, -EFAULT for invalid addresses. |
| 895 | */ |
| 896 | int pgste_perform_essa(struct mm_struct *mm, unsigned long hva, int orc, |
| 897 | unsigned long *oldpte, unsigned long *oldpgste) |
| 898 | { |
| 899 | unsigned long pgstev; |
| 900 | spinlock_t *ptl; |
| 901 | pgste_t pgste; |
| 902 | pte_t *ptep; |
| 903 | int res = 0; |
| 904 | |
| 905 | WARN_ON_ONCE(orc > ESSA_MAX); |
| 906 | if (unlikely(orc > ESSA_MAX)) |
| 907 | return -EINVAL; |
| 908 | ptep = get_locked_pte(mm, hva, &ptl); |
| 909 | if (unlikely(!ptep)) |
| 910 | return -EFAULT; |
| 911 | pgste = pgste_get_lock(ptep); |
| 912 | pgstev = pgste_val(pgste); |
| 913 | if (oldpte) |
| 914 | *oldpte = pte_val(*ptep); |
| 915 | if (oldpgste) |
| 916 | *oldpgste = pgstev; |
| 917 | |
| 918 | switch (orc) { |
| 919 | case ESSA_GET_STATE: |
| 920 | break; |
| 921 | case ESSA_SET_STABLE: |
| 922 | pgstev &= ~(_PGSTE_GPS_USAGE_MASK | _PGSTE_GPS_NODAT); |
| 923 | pgstev |= _PGSTE_GPS_USAGE_STABLE; |
| 924 | break; |
| 925 | case ESSA_SET_UNUSED: |
| 926 | pgstev &= ~_PGSTE_GPS_USAGE_MASK; |
| 927 | pgstev |= _PGSTE_GPS_USAGE_UNUSED; |
| 928 | if (pte_val(*ptep) & _PAGE_INVALID) |
| 929 | res = 1; |
| 930 | break; |
| 931 | case ESSA_SET_VOLATILE: |
| 932 | pgstev &= ~_PGSTE_GPS_USAGE_MASK; |
| 933 | pgstev |= _PGSTE_GPS_USAGE_VOLATILE; |
| 934 | if (pte_val(*ptep) & _PAGE_INVALID) |
| 935 | res = 1; |
| 936 | break; |
| 937 | case ESSA_SET_POT_VOLATILE: |
| 938 | pgstev &= ~_PGSTE_GPS_USAGE_MASK; |
| 939 | if (!(pte_val(*ptep) & _PAGE_INVALID)) { |
| 940 | pgstev |= _PGSTE_GPS_USAGE_POT_VOLATILE; |
| 941 | break; |
| 942 | } |
| 943 | if (pgstev & _PGSTE_GPS_ZERO) { |
| 944 | pgstev |= _PGSTE_GPS_USAGE_VOLATILE; |
| 945 | break; |
| 946 | } |
| 947 | if (!(pgstev & PGSTE_GC_BIT)) { |
| 948 | pgstev |= _PGSTE_GPS_USAGE_VOLATILE; |
| 949 | res = 1; |
| 950 | break; |
| 951 | } |
| 952 | break; |
| 953 | case ESSA_SET_STABLE_RESIDENT: |
| 954 | pgstev &= ~_PGSTE_GPS_USAGE_MASK; |
| 955 | pgstev |= _PGSTE_GPS_USAGE_STABLE; |
| 956 | /* |
| 957 | * Since the resident state can go away any time after this |
| 958 | * call, we will not make this page resident. We can revisit |
| 959 | * this decision if a guest will ever start using this. |
| 960 | */ |
| 961 | break; |
| 962 | case ESSA_SET_STABLE_IF_RESIDENT: |
| 963 | if (!(pte_val(*ptep) & _PAGE_INVALID)) { |
| 964 | pgstev &= ~_PGSTE_GPS_USAGE_MASK; |
| 965 | pgstev |= _PGSTE_GPS_USAGE_STABLE; |
| 966 | } |
| 967 | break; |
| 968 | case ESSA_SET_STABLE_NODAT: |
| 969 | pgstev &= ~_PGSTE_GPS_USAGE_MASK; |
| 970 | pgstev |= _PGSTE_GPS_USAGE_STABLE | _PGSTE_GPS_NODAT; |
| 971 | break; |
| 972 | default: |
| 973 | /* we should never get here! */ |
| 974 | break; |
| 975 | } |
| 976 | /* If we are discarding a page, set it to logical zero */ |
| 977 | if (res) |
| 978 | pgstev |= _PGSTE_GPS_ZERO; |
| 979 | |
| 980 | pgste_val(pgste) = pgstev; |
| 981 | pgste_set_unlock(ptep, pgste); |
| 982 | pte_unmap_unlock(ptep, ptl); |
| 983 | return res; |
| 984 | } |
| 985 | EXPORT_SYMBOL(pgste_perform_essa); |
| 986 | |
| 987 | /** |
| 988 | * set_pgste_bits - set specific PGSTE bits. |
| 989 | * @mm: the memory context. It must have PGSTEs, no check is performed here! |
| 990 | * @hva: the host virtual address of the page whose PGSTE is to be processed |
| 991 | * @bits: a bitmask representing the bits that will be touched |
| 992 | * @value: the values of the bits to be written. Only the bits in the mask |
| 993 | * will be written. |
| 994 | * |
| 995 | * Return: 0 on success, < 0 in case of error. |
| 996 | */ |
| 997 | int set_pgste_bits(struct mm_struct *mm, unsigned long hva, |
| 998 | unsigned long bits, unsigned long value) |
| 999 | { |
| 1000 | spinlock_t *ptl; |
| 1001 | pgste_t new; |
| 1002 | pte_t *ptep; |
| 1003 | |
| 1004 | ptep = get_locked_pte(mm, hva, &ptl); |
| 1005 | if (unlikely(!ptep)) |
| 1006 | return -EFAULT; |
| 1007 | new = pgste_get_lock(ptep); |
| 1008 | |
| 1009 | pgste_val(new) &= ~bits; |
| 1010 | pgste_val(new) |= value & bits; |
| 1011 | |
| 1012 | pgste_set_unlock(ptep, new); |
| 1013 | pte_unmap_unlock(ptep, ptl); |
| 1014 | return 0; |
| 1015 | } |
| 1016 | EXPORT_SYMBOL(set_pgste_bits); |
| 1017 | |
| 1018 | /** |
| 1019 | * get_pgste - get the current PGSTE for the given address. |
| 1020 | * @mm: the memory context. It must have PGSTEs, no check is performed here! |
| 1021 | * @hva: the host virtual address of the page whose PGSTE is to be processed |
| 1022 | * @pgstep: will be written with the current PGSTE for the given address. |
| 1023 | * |
| 1024 | * Return: 0 on success, < 0 in case of error. |
| 1025 | */ |
| 1026 | int get_pgste(struct mm_struct *mm, unsigned long hva, unsigned long *pgstep) |
| 1027 | { |
| 1028 | spinlock_t *ptl; |
| 1029 | pte_t *ptep; |
| 1030 | |
| 1031 | ptep = get_locked_pte(mm, hva, &ptl); |
| 1032 | if (unlikely(!ptep)) |
| 1033 | return -EFAULT; |
| 1034 | *pgstep = pgste_val(pgste_get(ptep)); |
| 1035 | pte_unmap_unlock(ptep, ptl); |
| 1036 | return 0; |
| 1037 | } |
| 1038 | EXPORT_SYMBOL(get_pgste); |
| 1039 | #endif |