1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright IBM Corp. 2007, 2011
4 * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
5 */
6
7 #include <linux/sched.h>
8 #include <linux/kernel.h>
9 #include <linux/errno.h>
10 #include <linux/gfp.h>
11 #include <linux/mm.h>
12 #include <linux/swap.h>
13 #include <linux/smp.h>
14 #include <linux/spinlock.h>
15 #include <linux/rcupdate.h>
16 #include <linux/slab.h>
17 #include <linux/swapops.h>
18 #include <linux/sysctl.h>
19 #include <linux/ksm.h>
20 #include <linux/mman.h>
21
22 #include <asm/tlb.h>
23 #include <asm/tlbflush.h>
24 #include <asm/mmu_context.h>
25 #include <asm/page-states.h>
26
pgprot_writecombine(pgprot_t prot)27 pgprot_t pgprot_writecombine(pgprot_t prot)
28 {
29 /*
30 * mio_wb_bit_mask may be set on a different CPU, but it is only set
31 * once at init and only read afterwards.
32 */
33 return __pgprot(pgprot_val(prot) | mio_wb_bit_mask);
34 }
35 EXPORT_SYMBOL_GPL(pgprot_writecombine);
36
pgprot_writethrough(pgprot_t prot)37 pgprot_t pgprot_writethrough(pgprot_t prot)
38 {
39 /*
40 * mio_wb_bit_mask may be set on a different CPU, but it is only set
41 * once at init and only read afterwards.
42 */
43 return __pgprot(pgprot_val(prot) & ~mio_wb_bit_mask);
44 }
45 EXPORT_SYMBOL_GPL(pgprot_writethrough);
46
ptep_ipte_local(struct mm_struct * mm,unsigned long addr,pte_t * ptep,int nodat)47 static inline void ptep_ipte_local(struct mm_struct *mm, unsigned long addr,
48 pte_t *ptep, int nodat)
49 {
50 unsigned long opt, asce;
51
52 if (MACHINE_HAS_TLB_GUEST) {
53 opt = 0;
54 asce = READ_ONCE(mm->context.gmap_asce);
55 if (asce == 0UL || nodat)
56 opt |= IPTE_NODAT;
57 if (asce != -1UL) {
58 asce = asce ? : mm->context.asce;
59 opt |= IPTE_GUEST_ASCE;
60 }
61 __ptep_ipte(addr, ptep, opt, asce, IPTE_LOCAL);
62 } else {
63 __ptep_ipte(addr, ptep, 0, 0, IPTE_LOCAL);
64 }
65 }
66
ptep_ipte_global(struct mm_struct * mm,unsigned long addr,pte_t * ptep,int nodat)67 static inline void ptep_ipte_global(struct mm_struct *mm, unsigned long addr,
68 pte_t *ptep, int nodat)
69 {
70 unsigned long opt, asce;
71
72 if (MACHINE_HAS_TLB_GUEST) {
73 opt = 0;
74 asce = READ_ONCE(mm->context.gmap_asce);
75 if (asce == 0UL || nodat)
76 opt |= IPTE_NODAT;
77 if (asce != -1UL) {
78 asce = asce ? : mm->context.asce;
79 opt |= IPTE_GUEST_ASCE;
80 }
81 __ptep_ipte(addr, ptep, opt, asce, IPTE_GLOBAL);
82 } else {
83 __ptep_ipte(addr, ptep, 0, 0, IPTE_GLOBAL);
84 }
85 }
86
ptep_flush_direct(struct mm_struct * mm,unsigned long addr,pte_t * ptep,int nodat)87 static inline pte_t ptep_flush_direct(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 (MACHINE_HAS_TLB_LC &&
98 cpumask_equal(mm_cpumask(mm), cpumask_of(smp_processor_id())))
99 ptep_ipte_local(mm, addr, ptep, nodat);
100 else
101 ptep_ipte_global(mm, addr, ptep, nodat);
102 atomic_dec(&mm->context.flush_count);
103 return old;
104 }
105
ptep_flush_lazy(struct mm_struct * mm,unsigned long addr,pte_t * ptep,int nodat)106 static inline pte_t ptep_flush_lazy(struct mm_struct *mm,
107 unsigned long addr, pte_t *ptep,
108 int nodat)
109 {
110 pte_t old;
111
112 old = *ptep;
113 if (unlikely(pte_val(old) & _PAGE_INVALID))
114 return old;
115 atomic_inc(&mm->context.flush_count);
116 if (cpumask_equal(&mm->context.cpu_attach_mask,
117 cpumask_of(smp_processor_id()))) {
118 pte_val(*ptep) |= _PAGE_INVALID;
119 mm->context.flush_mm = 1;
120 } else
121 ptep_ipte_global(mm, addr, ptep, nodat);
122 atomic_dec(&mm->context.flush_count);
123 return old;
124 }
125
pgste_get_lock(pte_t * ptep)126 static inline pgste_t pgste_get_lock(pte_t *ptep)
127 {
128 unsigned long new = 0;
129 #ifdef CONFIG_PGSTE
130 unsigned long old;
131
132 asm(
133 " lg %0,%2\n"
134 "0: lgr %1,%0\n"
135 " nihh %0,0xff7f\n" /* clear PCL bit in old */
136 " oihh %1,0x0080\n" /* set PCL bit in new */
137 " csg %0,%1,%2\n"
138 " jl 0b\n"
139 : "=&d" (old), "=&d" (new), "=Q" (ptep[PTRS_PER_PTE])
140 : "Q" (ptep[PTRS_PER_PTE]) : "cc", "memory");
141 #endif
142 return __pgste(new);
143 }
144
pgste_set_unlock(pte_t * ptep,pgste_t pgste)145 static inline void pgste_set_unlock(pte_t *ptep, pgste_t pgste)
146 {
147 #ifdef CONFIG_PGSTE
148 asm(
149 " nihh %1,0xff7f\n" /* clear PCL bit */
150 " stg %1,%0\n"
151 : "=Q" (ptep[PTRS_PER_PTE])
152 : "d" (pgste_val(pgste)), "Q" (ptep[PTRS_PER_PTE])
153 : "cc", "memory");
154 #endif
155 }
156
pgste_get(pte_t * ptep)157 static inline pgste_t pgste_get(pte_t *ptep)
158 {
159 unsigned long pgste = 0;
160 #ifdef CONFIG_PGSTE
161 pgste = *(unsigned long *)(ptep + PTRS_PER_PTE);
162 #endif
163 return __pgste(pgste);
164 }
165
pgste_set(pte_t * ptep,pgste_t pgste)166 static inline void pgste_set(pte_t *ptep, pgste_t pgste)
167 {
168 #ifdef CONFIG_PGSTE
169 *(pgste_t *)(ptep + PTRS_PER_PTE) = pgste;
170 #endif
171 }
172
pgste_update_all(pte_t pte,pgste_t pgste,struct mm_struct * mm)173 static inline pgste_t pgste_update_all(pte_t pte, pgste_t pgste,
174 struct mm_struct *mm)
175 {
176 #ifdef CONFIG_PGSTE
177 unsigned long address, bits, skey;
178
179 if (!mm_uses_skeys(mm) || pte_val(pte) & _PAGE_INVALID)
180 return pgste;
181 address = pte_val(pte) & PAGE_MASK;
182 skey = (unsigned long) page_get_storage_key(address);
183 bits = skey & (_PAGE_CHANGED | _PAGE_REFERENCED);
184 /* Transfer page changed & referenced bit to guest bits in pgste */
185 pgste_val(pgste) |= bits << 48; /* GR bit & GC bit */
186 /* Copy page access key and fetch protection bit to pgste */
187 pgste_val(pgste) &= ~(PGSTE_ACC_BITS | PGSTE_FP_BIT);
188 pgste_val(pgste) |= (skey & (_PAGE_ACC_BITS | _PAGE_FP_BIT)) << 56;
189 #endif
190 return pgste;
191
192 }
193
pgste_set_key(pte_t * ptep,pgste_t pgste,pte_t entry,struct mm_struct * mm)194 static inline void pgste_set_key(pte_t *ptep, pgste_t pgste, pte_t entry,
195 struct mm_struct *mm)
196 {
197 #ifdef CONFIG_PGSTE
198 unsigned long address;
199 unsigned long nkey;
200
201 if (!mm_uses_skeys(mm) || pte_val(entry) & _PAGE_INVALID)
202 return;
203 VM_BUG_ON(!(pte_val(*ptep) & _PAGE_INVALID));
204 address = pte_val(entry) & PAGE_MASK;
205 /*
206 * Set page access key and fetch protection bit from pgste.
207 * The guest C/R information is still in the PGSTE, set real
208 * key C/R to 0.
209 */
210 nkey = (pgste_val(pgste) & (PGSTE_ACC_BITS | PGSTE_FP_BIT)) >> 56;
211 nkey |= (pgste_val(pgste) & (PGSTE_GR_BIT | PGSTE_GC_BIT)) >> 48;
212 page_set_storage_key(address, nkey, 0);
213 #endif
214 }
215
pgste_set_pte(pte_t * ptep,pgste_t pgste,pte_t entry)216 static inline pgste_t pgste_set_pte(pte_t *ptep, pgste_t pgste, pte_t entry)
217 {
218 #ifdef CONFIG_PGSTE
219 if ((pte_val(entry) & _PAGE_PRESENT) &&
220 (pte_val(entry) & _PAGE_WRITE) &&
221 !(pte_val(entry) & _PAGE_INVALID)) {
222 if (!MACHINE_HAS_ESOP) {
223 /*
224 * Without enhanced suppression-on-protection force
225 * the dirty bit on for all writable ptes.
226 */
227 pte_val(entry) |= _PAGE_DIRTY;
228 pte_val(entry) &= ~_PAGE_PROTECT;
229 }
230 if (!(pte_val(entry) & _PAGE_PROTECT))
231 /* This pte allows write access, set user-dirty */
232 pgste_val(pgste) |= PGSTE_UC_BIT;
233 }
234 #endif
235 *ptep = entry;
236 return pgste;
237 }
238
pgste_pte_notify(struct mm_struct * mm,unsigned long addr,pte_t * ptep,pgste_t pgste)239 static inline pgste_t pgste_pte_notify(struct mm_struct *mm,
240 unsigned long addr,
241 pte_t *ptep, pgste_t pgste)
242 {
243 #ifdef CONFIG_PGSTE
244 unsigned long bits;
245
246 bits = pgste_val(pgste) & (PGSTE_IN_BIT | PGSTE_VSIE_BIT);
247 if (bits) {
248 pgste_val(pgste) ^= bits;
249 ptep_notify(mm, addr, ptep, bits);
250 }
251 #endif
252 return pgste;
253 }
254
ptep_xchg_start(struct mm_struct * mm,unsigned long addr,pte_t * ptep)255 static inline pgste_t ptep_xchg_start(struct mm_struct *mm,
256 unsigned long addr, pte_t *ptep)
257 {
258 pgste_t pgste = __pgste(0);
259
260 if (mm_has_pgste(mm)) {
261 pgste = pgste_get_lock(ptep);
262 pgste = pgste_pte_notify(mm, addr, ptep, pgste);
263 }
264 return pgste;
265 }
266
ptep_xchg_commit(struct mm_struct * mm,unsigned long addr,pte_t * ptep,pgste_t pgste,pte_t old,pte_t new)267 static inline pte_t ptep_xchg_commit(struct mm_struct *mm,
268 unsigned long addr, pte_t *ptep,
269 pgste_t pgste, pte_t old, pte_t new)
270 {
271 if (mm_has_pgste(mm)) {
272 if (pte_val(old) & _PAGE_INVALID)
273 pgste_set_key(ptep, pgste, new, mm);
274 if (pte_val(new) & _PAGE_INVALID) {
275 pgste = pgste_update_all(old, pgste, mm);
276 if ((pgste_val(pgste) & _PGSTE_GPS_USAGE_MASK) ==
277 _PGSTE_GPS_USAGE_UNUSED)
278 pte_val(old) |= _PAGE_UNUSED;
279 }
280 pgste = pgste_set_pte(ptep, pgste, new);
281 pgste_set_unlock(ptep, pgste);
282 } else {
283 *ptep = new;
284 }
285 return old;
286 }
287
ptep_xchg_direct(struct mm_struct * mm,unsigned long addr,pte_t * ptep,pte_t new)288 pte_t ptep_xchg_direct(struct mm_struct *mm, unsigned long addr,
289 pte_t *ptep, pte_t new)
290 {
291 pgste_t pgste;
292 pte_t old;
293 int nodat;
294
295 preempt_disable();
296 pgste = ptep_xchg_start(mm, addr, ptep);
297 nodat = !!(pgste_val(pgste) & _PGSTE_GPS_NODAT);
298 old = ptep_flush_direct(mm, addr, ptep, nodat);
299 old = ptep_xchg_commit(mm, addr, ptep, pgste, old, new);
300 preempt_enable();
301 return old;
302 }
303 EXPORT_SYMBOL(ptep_xchg_direct);
304
ptep_xchg_lazy(struct mm_struct * mm,unsigned long addr,pte_t * ptep,pte_t new)305 pte_t ptep_xchg_lazy(struct mm_struct *mm, unsigned long addr,
306 pte_t *ptep, pte_t new)
307 {
308 pgste_t pgste;
309 pte_t old;
310 int nodat;
311
312 preempt_disable();
313 pgste = ptep_xchg_start(mm, addr, ptep);
314 nodat = !!(pgste_val(pgste) & _PGSTE_GPS_NODAT);
315 old = ptep_flush_lazy(mm, addr, ptep, nodat);
316 old = ptep_xchg_commit(mm, addr, ptep, pgste, old, new);
317 preempt_enable();
318 return old;
319 }
320 EXPORT_SYMBOL(ptep_xchg_lazy);
321
ptep_modify_prot_start(struct vm_area_struct * vma,unsigned long addr,pte_t * ptep)322 pte_t ptep_modify_prot_start(struct vm_area_struct *vma, unsigned long addr,
323 pte_t *ptep)
324 {
325 pgste_t pgste;
326 pte_t old;
327 int nodat;
328 struct mm_struct *mm = vma->vm_mm;
329
330 preempt_disable();
331 pgste = ptep_xchg_start(mm, addr, ptep);
332 nodat = !!(pgste_val(pgste) & _PGSTE_GPS_NODAT);
333 old = ptep_flush_lazy(mm, addr, ptep, nodat);
334 if (mm_has_pgste(mm)) {
335 pgste = pgste_update_all(old, pgste, mm);
336 pgste_set(ptep, pgste);
337 }
338 return old;
339 }
340
ptep_modify_prot_commit(struct vm_area_struct * vma,unsigned long addr,pte_t * ptep,pte_t old_pte,pte_t pte)341 void ptep_modify_prot_commit(struct vm_area_struct *vma, unsigned long addr,
342 pte_t *ptep, pte_t old_pte, pte_t pte)
343 {
344 pgste_t pgste;
345 struct mm_struct *mm = vma->vm_mm;
346
347 if (!MACHINE_HAS_NX)
348 pte_val(pte) &= ~_PAGE_NOEXEC;
349 if (mm_has_pgste(mm)) {
350 pgste = pgste_get(ptep);
351 pgste_set_key(ptep, pgste, pte, mm);
352 pgste = pgste_set_pte(ptep, pgste, pte);
353 pgste_set_unlock(ptep, pgste);
354 } else {
355 *ptep = pte;
356 }
357 preempt_enable();
358 }
359
pmdp_idte_local(struct mm_struct * mm,unsigned long addr,pmd_t * pmdp)360 static inline void pmdp_idte_local(struct mm_struct *mm,
361 unsigned long addr, pmd_t *pmdp)
362 {
363 if (MACHINE_HAS_TLB_GUEST)
364 __pmdp_idte(addr, pmdp, IDTE_NODAT | IDTE_GUEST_ASCE,
365 mm->context.asce, IDTE_LOCAL);
366 else
367 __pmdp_idte(addr, pmdp, 0, 0, IDTE_LOCAL);
368 if (mm_has_pgste(mm) && mm->context.allow_gmap_hpage_1m)
369 gmap_pmdp_idte_local(mm, addr);
370 }
371
pmdp_idte_global(struct mm_struct * mm,unsigned long addr,pmd_t * pmdp)372 static inline void pmdp_idte_global(struct mm_struct *mm,
373 unsigned long addr, pmd_t *pmdp)
374 {
375 if (MACHINE_HAS_TLB_GUEST) {
376 __pmdp_idte(addr, pmdp, IDTE_NODAT | IDTE_GUEST_ASCE,
377 mm->context.asce, IDTE_GLOBAL);
378 if (mm_has_pgste(mm) && mm->context.allow_gmap_hpage_1m)
379 gmap_pmdp_idte_global(mm, addr);
380 } else if (MACHINE_HAS_IDTE) {
381 __pmdp_idte(addr, pmdp, 0, 0, IDTE_GLOBAL);
382 if (mm_has_pgste(mm) && mm->context.allow_gmap_hpage_1m)
383 gmap_pmdp_idte_global(mm, addr);
384 } else {
385 __pmdp_csp(pmdp);
386 if (mm_has_pgste(mm) && mm->context.allow_gmap_hpage_1m)
387 gmap_pmdp_csp(mm, addr);
388 }
389 }
390
pmdp_flush_direct(struct mm_struct * mm,unsigned long addr,pmd_t * pmdp)391 static inline pmd_t pmdp_flush_direct(struct mm_struct *mm,
392 unsigned long addr, pmd_t *pmdp)
393 {
394 pmd_t old;
395
396 old = *pmdp;
397 if (pmd_val(old) & _SEGMENT_ENTRY_INVALID)
398 return old;
399 atomic_inc(&mm->context.flush_count);
400 if (MACHINE_HAS_TLB_LC &&
401 cpumask_equal(mm_cpumask(mm), cpumask_of(smp_processor_id())))
402 pmdp_idte_local(mm, addr, pmdp);
403 else
404 pmdp_idte_global(mm, addr, pmdp);
405 atomic_dec(&mm->context.flush_count);
406 return old;
407 }
408
pmdp_flush_lazy(struct mm_struct * mm,unsigned long addr,pmd_t * pmdp)409 static inline pmd_t pmdp_flush_lazy(struct mm_struct *mm,
410 unsigned long addr, pmd_t *pmdp)
411 {
412 pmd_t old;
413
414 old = *pmdp;
415 if (pmd_val(old) & _SEGMENT_ENTRY_INVALID)
416 return old;
417 atomic_inc(&mm->context.flush_count);
418 if (cpumask_equal(&mm->context.cpu_attach_mask,
419 cpumask_of(smp_processor_id()))) {
420 pmd_val(*pmdp) |= _SEGMENT_ENTRY_INVALID;
421 mm->context.flush_mm = 1;
422 if (mm_has_pgste(mm))
423 gmap_pmdp_invalidate(mm, addr);
424 } else {
425 pmdp_idte_global(mm, addr, pmdp);
426 }
427 atomic_dec(&mm->context.flush_count);
428 return old;
429 }
430
431 #ifdef CONFIG_PGSTE
pmd_alloc_map(struct mm_struct * mm,unsigned long addr)432 static pmd_t *pmd_alloc_map(struct mm_struct *mm, unsigned long addr)
433 {
434 pgd_t *pgd;
435 p4d_t *p4d;
436 pud_t *pud;
437 pmd_t *pmd;
438
439 pgd = pgd_offset(mm, addr);
440 p4d = p4d_alloc(mm, pgd, addr);
441 if (!p4d)
442 return NULL;
443 pud = pud_alloc(mm, p4d, addr);
444 if (!pud)
445 return NULL;
446 pmd = pmd_alloc(mm, pud, addr);
447 return pmd;
448 }
449 #endif
450
pmdp_xchg_direct(struct mm_struct * mm,unsigned long addr,pmd_t * pmdp,pmd_t new)451 pmd_t pmdp_xchg_direct(struct mm_struct *mm, unsigned long addr,
452 pmd_t *pmdp, pmd_t new)
453 {
454 pmd_t old;
455
456 preempt_disable();
457 old = pmdp_flush_direct(mm, addr, pmdp);
458 *pmdp = new;
459 preempt_enable();
460 return old;
461 }
462 EXPORT_SYMBOL(pmdp_xchg_direct);
463
pmdp_xchg_lazy(struct mm_struct * mm,unsigned long addr,pmd_t * pmdp,pmd_t new)464 pmd_t pmdp_xchg_lazy(struct mm_struct *mm, unsigned long addr,
465 pmd_t *pmdp, pmd_t new)
466 {
467 pmd_t old;
468
469 preempt_disable();
470 old = pmdp_flush_lazy(mm, addr, pmdp);
471 *pmdp = new;
472 preempt_enable();
473 return old;
474 }
475 EXPORT_SYMBOL(pmdp_xchg_lazy);
476
pudp_idte_local(struct mm_struct * mm,unsigned long addr,pud_t * pudp)477 static inline void pudp_idte_local(struct mm_struct *mm,
478 unsigned long addr, pud_t *pudp)
479 {
480 if (MACHINE_HAS_TLB_GUEST)
481 __pudp_idte(addr, pudp, IDTE_NODAT | IDTE_GUEST_ASCE,
482 mm->context.asce, IDTE_LOCAL);
483 else
484 __pudp_idte(addr, pudp, 0, 0, IDTE_LOCAL);
485 }
486
pudp_idte_global(struct mm_struct * mm,unsigned long addr,pud_t * pudp)487 static inline void pudp_idte_global(struct mm_struct *mm,
488 unsigned long addr, pud_t *pudp)
489 {
490 if (MACHINE_HAS_TLB_GUEST)
491 __pudp_idte(addr, pudp, IDTE_NODAT | IDTE_GUEST_ASCE,
492 mm->context.asce, IDTE_GLOBAL);
493 else if (MACHINE_HAS_IDTE)
494 __pudp_idte(addr, pudp, 0, 0, IDTE_GLOBAL);
495 else
496 /*
497 * Invalid bit position is the same for pmd and pud, so we can
498 * re-use _pmd_csp() here
499 */
500 __pmdp_csp((pmd_t *) pudp);
501 }
502
pudp_flush_direct(struct mm_struct * mm,unsigned long addr,pud_t * pudp)503 static inline pud_t pudp_flush_direct(struct mm_struct *mm,
504 unsigned long addr, pud_t *pudp)
505 {
506 pud_t old;
507
508 old = *pudp;
509 if (pud_val(old) & _REGION_ENTRY_INVALID)
510 return old;
511 atomic_inc(&mm->context.flush_count);
512 if (MACHINE_HAS_TLB_LC &&
513 cpumask_equal(mm_cpumask(mm), cpumask_of(smp_processor_id())))
514 pudp_idte_local(mm, addr, pudp);
515 else
516 pudp_idte_global(mm, addr, pudp);
517 atomic_dec(&mm->context.flush_count);
518 return old;
519 }
520
pudp_xchg_direct(struct mm_struct * mm,unsigned long addr,pud_t * pudp,pud_t new)521 pud_t pudp_xchg_direct(struct mm_struct *mm, unsigned long addr,
522 pud_t *pudp, pud_t new)
523 {
524 pud_t old;
525
526 preempt_disable();
527 old = pudp_flush_direct(mm, addr, pudp);
528 *pudp = new;
529 preempt_enable();
530 return old;
531 }
532 EXPORT_SYMBOL(pudp_xchg_direct);
533
534 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
pgtable_trans_huge_deposit(struct mm_struct * mm,pmd_t * pmdp,pgtable_t pgtable)535 void pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp,
536 pgtable_t pgtable)
537 {
538 struct list_head *lh = (struct list_head *) pgtable;
539
540 assert_spin_locked(pmd_lockptr(mm, pmdp));
541
542 /* FIFO */
543 if (!pmd_huge_pte(mm, pmdp))
544 INIT_LIST_HEAD(lh);
545 else
546 list_add(lh, (struct list_head *) pmd_huge_pte(mm, pmdp));
547 pmd_huge_pte(mm, pmdp) = pgtable;
548 }
549
pgtable_trans_huge_withdraw(struct mm_struct * mm,pmd_t * pmdp)550 pgtable_t pgtable_trans_huge_withdraw(struct mm_struct *mm, pmd_t *pmdp)
551 {
552 struct list_head *lh;
553 pgtable_t pgtable;
554 pte_t *ptep;
555
556 assert_spin_locked(pmd_lockptr(mm, pmdp));
557
558 /* FIFO */
559 pgtable = pmd_huge_pte(mm, pmdp);
560 lh = (struct list_head *) pgtable;
561 if (list_empty(lh))
562 pmd_huge_pte(mm, pmdp) = NULL;
563 else {
564 pmd_huge_pte(mm, pmdp) = (pgtable_t) lh->next;
565 list_del(lh);
566 }
567 ptep = (pte_t *) pgtable;
568 pte_val(*ptep) = _PAGE_INVALID;
569 ptep++;
570 pte_val(*ptep) = _PAGE_INVALID;
571 return pgtable;
572 }
573 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
574
575 #ifdef CONFIG_PGSTE
ptep_set_pte_at(struct mm_struct * mm,unsigned long addr,pte_t * ptep,pte_t entry)576 void ptep_set_pte_at(struct mm_struct *mm, unsigned long addr,
577 pte_t *ptep, pte_t entry)
578 {
579 pgste_t pgste;
580
581 /* the mm_has_pgste() check is done in set_pte_at() */
582 preempt_disable();
583 pgste = pgste_get_lock(ptep);
584 pgste_val(pgste) &= ~_PGSTE_GPS_ZERO;
585 pgste_set_key(ptep, pgste, entry, mm);
586 pgste = pgste_set_pte(ptep, pgste, entry);
587 pgste_set_unlock(ptep, pgste);
588 preempt_enable();
589 }
590
ptep_set_notify(struct mm_struct * mm,unsigned long addr,pte_t * ptep)591 void ptep_set_notify(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
592 {
593 pgste_t pgste;
594
595 preempt_disable();
596 pgste = pgste_get_lock(ptep);
597 pgste_val(pgste) |= PGSTE_IN_BIT;
598 pgste_set_unlock(ptep, pgste);
599 preempt_enable();
600 }
601
602 /**
603 * ptep_force_prot - change access rights of a locked pte
604 * @mm: pointer to the process mm_struct
605 * @addr: virtual address in the guest address space
606 * @ptep: pointer to the page table entry
607 * @prot: indicates guest access rights: PROT_NONE, PROT_READ or PROT_WRITE
608 * @bit: pgste bit to set (e.g. for notification)
609 *
610 * Returns 0 if the access rights were changed and -EAGAIN if the current
611 * and requested access rights are incompatible.
612 */
ptep_force_prot(struct mm_struct * mm,unsigned long addr,pte_t * ptep,int prot,unsigned long bit)613 int ptep_force_prot(struct mm_struct *mm, unsigned long addr,
614 pte_t *ptep, int prot, unsigned long bit)
615 {
616 pte_t entry;
617 pgste_t pgste;
618 int pte_i, pte_p, nodat;
619
620 pgste = pgste_get_lock(ptep);
621 entry = *ptep;
622 /* Check pte entry after all locks have been acquired */
623 pte_i = pte_val(entry) & _PAGE_INVALID;
624 pte_p = pte_val(entry) & _PAGE_PROTECT;
625 if ((pte_i && (prot != PROT_NONE)) ||
626 (pte_p && (prot & PROT_WRITE))) {
627 pgste_set_unlock(ptep, pgste);
628 return -EAGAIN;
629 }
630 /* Change access rights and set pgste bit */
631 nodat = !!(pgste_val(pgste) & _PGSTE_GPS_NODAT);
632 if (prot == PROT_NONE && !pte_i) {
633 ptep_flush_direct(mm, addr, ptep, nodat);
634 pgste = pgste_update_all(entry, pgste, mm);
635 pte_val(entry) |= _PAGE_INVALID;
636 }
637 if (prot == PROT_READ && !pte_p) {
638 ptep_flush_direct(mm, addr, ptep, nodat);
639 pte_val(entry) &= ~_PAGE_INVALID;
640 pte_val(entry) |= _PAGE_PROTECT;
641 }
642 pgste_val(pgste) |= bit;
643 pgste = pgste_set_pte(ptep, pgste, entry);
644 pgste_set_unlock(ptep, pgste);
645 return 0;
646 }
647
ptep_shadow_pte(struct mm_struct * mm,unsigned long saddr,pte_t * sptep,pte_t * tptep,pte_t pte)648 int ptep_shadow_pte(struct mm_struct *mm, unsigned long saddr,
649 pte_t *sptep, pte_t *tptep, pte_t pte)
650 {
651 pgste_t spgste, tpgste;
652 pte_t spte, tpte;
653 int rc = -EAGAIN;
654
655 if (!(pte_val(*tptep) & _PAGE_INVALID))
656 return 0; /* already shadowed */
657 spgste = pgste_get_lock(sptep);
658 spte = *sptep;
659 if (!(pte_val(spte) & _PAGE_INVALID) &&
660 !((pte_val(spte) & _PAGE_PROTECT) &&
661 !(pte_val(pte) & _PAGE_PROTECT))) {
662 pgste_val(spgste) |= PGSTE_VSIE_BIT;
663 tpgste = pgste_get_lock(tptep);
664 pte_val(tpte) = (pte_val(spte) & PAGE_MASK) |
665 (pte_val(pte) & _PAGE_PROTECT);
666 /* don't touch the storage key - it belongs to parent pgste */
667 tpgste = pgste_set_pte(tptep, tpgste, tpte);
668 pgste_set_unlock(tptep, tpgste);
669 rc = 1;
670 }
671 pgste_set_unlock(sptep, spgste);
672 return rc;
673 }
674
ptep_unshadow_pte(struct mm_struct * mm,unsigned long saddr,pte_t * ptep)675 void ptep_unshadow_pte(struct mm_struct *mm, unsigned long saddr, pte_t *ptep)
676 {
677 pgste_t pgste;
678 int nodat;
679
680 pgste = pgste_get_lock(ptep);
681 /* notifier is called by the caller */
682 nodat = !!(pgste_val(pgste) & _PGSTE_GPS_NODAT);
683 ptep_flush_direct(mm, saddr, ptep, nodat);
684 /* don't touch the storage key - it belongs to parent pgste */
685 pgste = pgste_set_pte(ptep, pgste, __pte(_PAGE_INVALID));
686 pgste_set_unlock(ptep, pgste);
687 }
688
ptep_zap_swap_entry(struct mm_struct * mm,swp_entry_t entry)689 static void ptep_zap_swap_entry(struct mm_struct *mm, swp_entry_t entry)
690 {
691 if (!non_swap_entry(entry))
692 dec_mm_counter(mm, MM_SWAPENTS);
693 else if (is_migration_entry(entry)) {
694 struct page *page = migration_entry_to_page(entry);
695
696 dec_mm_counter(mm, mm_counter(page));
697 }
698 free_swap_and_cache(entry);
699 }
700
ptep_zap_unused(struct mm_struct * mm,unsigned long addr,pte_t * ptep,int reset)701 void ptep_zap_unused(struct mm_struct *mm, unsigned long addr,
702 pte_t *ptep, int reset)
703 {
704 unsigned long pgstev;
705 pgste_t pgste;
706 pte_t pte;
707
708 /* Zap unused and logically-zero pages */
709 preempt_disable();
710 pgste = pgste_get_lock(ptep);
711 pgstev = pgste_val(pgste);
712 pte = *ptep;
713 if (!reset && pte_swap(pte) &&
714 ((pgstev & _PGSTE_GPS_USAGE_MASK) == _PGSTE_GPS_USAGE_UNUSED ||
715 (pgstev & _PGSTE_GPS_ZERO))) {
716 ptep_zap_swap_entry(mm, pte_to_swp_entry(pte));
717 pte_clear(mm, addr, ptep);
718 }
719 if (reset)
720 pgste_val(pgste) &= ~_PGSTE_GPS_USAGE_MASK;
721 pgste_set_unlock(ptep, pgste);
722 preempt_enable();
723 }
724
ptep_zap_key(struct mm_struct * mm,unsigned long addr,pte_t * ptep)725 void ptep_zap_key(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
726 {
727 unsigned long ptev;
728 pgste_t pgste;
729
730 /* Clear storage key ACC and F, but set R/C */
731 preempt_disable();
732 pgste = pgste_get_lock(ptep);
733 pgste_val(pgste) &= ~(PGSTE_ACC_BITS | PGSTE_FP_BIT);
734 pgste_val(pgste) |= PGSTE_GR_BIT | PGSTE_GC_BIT;
735 ptev = pte_val(*ptep);
736 if (!(ptev & _PAGE_INVALID) && (ptev & _PAGE_WRITE))
737 page_set_storage_key(ptev & PAGE_MASK, PAGE_DEFAULT_KEY, 1);
738 pgste_set_unlock(ptep, pgste);
739 preempt_enable();
740 }
741
742 /*
743 * Test and reset if a guest page is dirty
744 */
ptep_test_and_clear_uc(struct mm_struct * mm,unsigned long addr,pte_t * ptep)745 bool ptep_test_and_clear_uc(struct mm_struct *mm, unsigned long addr,
746 pte_t *ptep)
747 {
748 pgste_t pgste;
749 pte_t pte;
750 bool dirty;
751 int nodat;
752
753 pgste = pgste_get_lock(ptep);
754 dirty = !!(pgste_val(pgste) & PGSTE_UC_BIT);
755 pgste_val(pgste) &= ~PGSTE_UC_BIT;
756 pte = *ptep;
757 if (dirty && (pte_val(pte) & _PAGE_PRESENT)) {
758 pgste = pgste_pte_notify(mm, addr, ptep, pgste);
759 nodat = !!(pgste_val(pgste) & _PGSTE_GPS_NODAT);
760 ptep_ipte_global(mm, addr, ptep, nodat);
761 if (MACHINE_HAS_ESOP || !(pte_val(pte) & _PAGE_WRITE))
762 pte_val(pte) |= _PAGE_PROTECT;
763 else
764 pte_val(pte) |= _PAGE_INVALID;
765 *ptep = pte;
766 }
767 pgste_set_unlock(ptep, pgste);
768 return dirty;
769 }
770 EXPORT_SYMBOL_GPL(ptep_test_and_clear_uc);
771
set_guest_storage_key(struct mm_struct * mm,unsigned long addr,unsigned char key,bool nq)772 int set_guest_storage_key(struct mm_struct *mm, unsigned long addr,
773 unsigned char key, bool nq)
774 {
775 unsigned long keyul, paddr;
776 spinlock_t *ptl;
777 pgste_t old, new;
778 pmd_t *pmdp;
779 pte_t *ptep;
780
781 pmdp = pmd_alloc_map(mm, addr);
782 if (unlikely(!pmdp))
783 return -EFAULT;
784
785 ptl = pmd_lock(mm, pmdp);
786 if (!pmd_present(*pmdp)) {
787 spin_unlock(ptl);
788 return -EFAULT;
789 }
790
791 if (pmd_large(*pmdp)) {
792 paddr = pmd_val(*pmdp) & HPAGE_MASK;
793 paddr |= addr & ~HPAGE_MASK;
794 /*
795 * Huge pmds need quiescing operations, they are
796 * always mapped.
797 */
798 page_set_storage_key(paddr, key, 1);
799 spin_unlock(ptl);
800 return 0;
801 }
802 spin_unlock(ptl);
803
804 ptep = pte_alloc_map_lock(mm, pmdp, addr, &ptl);
805 if (unlikely(!ptep))
806 return -EFAULT;
807
808 new = old = pgste_get_lock(ptep);
809 pgste_val(new) &= ~(PGSTE_GR_BIT | PGSTE_GC_BIT |
810 PGSTE_ACC_BITS | PGSTE_FP_BIT);
811 keyul = (unsigned long) key;
812 pgste_val(new) |= (keyul & (_PAGE_CHANGED | _PAGE_REFERENCED)) << 48;
813 pgste_val(new) |= (keyul & (_PAGE_ACC_BITS | _PAGE_FP_BIT)) << 56;
814 if (!(pte_val(*ptep) & _PAGE_INVALID)) {
815 unsigned long bits, skey;
816
817 paddr = pte_val(*ptep) & PAGE_MASK;
818 skey = (unsigned long) page_get_storage_key(paddr);
819 bits = skey & (_PAGE_CHANGED | _PAGE_REFERENCED);
820 skey = key & (_PAGE_ACC_BITS | _PAGE_FP_BIT);
821 /* Set storage key ACC and FP */
822 page_set_storage_key(paddr, skey, !nq);
823 /* Merge host changed & referenced into pgste */
824 pgste_val(new) |= bits << 52;
825 }
826 /* changing the guest storage key is considered a change of the page */
827 if ((pgste_val(new) ^ pgste_val(old)) &
828 (PGSTE_ACC_BITS | PGSTE_FP_BIT | PGSTE_GR_BIT | PGSTE_GC_BIT))
829 pgste_val(new) |= PGSTE_UC_BIT;
830
831 pgste_set_unlock(ptep, new);
832 pte_unmap_unlock(ptep, ptl);
833 return 0;
834 }
835 EXPORT_SYMBOL(set_guest_storage_key);
836
837 /**
838 * Conditionally set a guest storage key (handling csske).
839 * oldkey will be updated when either mr or mc is set and a pointer is given.
840 *
841 * Returns 0 if a guests storage key update wasn't necessary, 1 if the guest
842 * storage key was updated and -EFAULT on access errors.
843 */
cond_set_guest_storage_key(struct mm_struct * mm,unsigned long addr,unsigned char key,unsigned char * oldkey,bool nq,bool mr,bool mc)844 int cond_set_guest_storage_key(struct mm_struct *mm, unsigned long addr,
845 unsigned char key, unsigned char *oldkey,
846 bool nq, bool mr, bool mc)
847 {
848 unsigned char tmp, mask = _PAGE_ACC_BITS | _PAGE_FP_BIT;
849 int rc;
850
851 /* we can drop the pgste lock between getting and setting the key */
852 if (mr | mc) {
853 rc = get_guest_storage_key(current->mm, addr, &tmp);
854 if (rc)
855 return rc;
856 if (oldkey)
857 *oldkey = tmp;
858 if (!mr)
859 mask |= _PAGE_REFERENCED;
860 if (!mc)
861 mask |= _PAGE_CHANGED;
862 if (!((tmp ^ key) & mask))
863 return 0;
864 }
865 rc = set_guest_storage_key(current->mm, addr, key, nq);
866 return rc < 0 ? rc : 1;
867 }
868 EXPORT_SYMBOL(cond_set_guest_storage_key);
869
870 /**
871 * Reset a guest reference bit (rrbe), returning the reference and changed bit.
872 *
873 * Returns < 0 in case of error, otherwise the cc to be reported to the guest.
874 */
reset_guest_reference_bit(struct mm_struct * mm,unsigned long addr)875 int reset_guest_reference_bit(struct mm_struct *mm, unsigned long addr)
876 {
877 spinlock_t *ptl;
878 unsigned long paddr;
879 pgste_t old, new;
880 pmd_t *pmdp;
881 pte_t *ptep;
882 int cc = 0;
883
884 pmdp = pmd_alloc_map(mm, addr);
885 if (unlikely(!pmdp))
886 return -EFAULT;
887
888 ptl = pmd_lock(mm, pmdp);
889 if (!pmd_present(*pmdp)) {
890 spin_unlock(ptl);
891 return -EFAULT;
892 }
893
894 if (pmd_large(*pmdp)) {
895 paddr = pmd_val(*pmdp) & HPAGE_MASK;
896 paddr |= addr & ~HPAGE_MASK;
897 cc = page_reset_referenced(paddr);
898 spin_unlock(ptl);
899 return cc;
900 }
901 spin_unlock(ptl);
902
903 ptep = pte_alloc_map_lock(mm, pmdp, addr, &ptl);
904 if (unlikely(!ptep))
905 return -EFAULT;
906
907 new = old = pgste_get_lock(ptep);
908 /* Reset guest reference bit only */
909 pgste_val(new) &= ~PGSTE_GR_BIT;
910
911 if (!(pte_val(*ptep) & _PAGE_INVALID)) {
912 paddr = pte_val(*ptep) & PAGE_MASK;
913 cc = page_reset_referenced(paddr);
914 /* Merge real referenced bit into host-set */
915 pgste_val(new) |= ((unsigned long) cc << 53) & PGSTE_HR_BIT;
916 }
917 /* Reflect guest's logical view, not physical */
918 cc |= (pgste_val(old) & (PGSTE_GR_BIT | PGSTE_GC_BIT)) >> 49;
919 /* Changing the guest storage key is considered a change of the page */
920 if ((pgste_val(new) ^ pgste_val(old)) & PGSTE_GR_BIT)
921 pgste_val(new) |= PGSTE_UC_BIT;
922
923 pgste_set_unlock(ptep, new);
924 pte_unmap_unlock(ptep, ptl);
925 return cc;
926 }
927 EXPORT_SYMBOL(reset_guest_reference_bit);
928
get_guest_storage_key(struct mm_struct * mm,unsigned long addr,unsigned char * key)929 int get_guest_storage_key(struct mm_struct *mm, unsigned long addr,
930 unsigned char *key)
931 {
932 unsigned long paddr;
933 spinlock_t *ptl;
934 pgste_t pgste;
935 pmd_t *pmdp;
936 pte_t *ptep;
937
938 pmdp = pmd_alloc_map(mm, addr);
939 if (unlikely(!pmdp))
940 return -EFAULT;
941
942 ptl = pmd_lock(mm, pmdp);
943 if (!pmd_present(*pmdp)) {
944 /* Not yet mapped memory has a zero key */
945 spin_unlock(ptl);
946 *key = 0;
947 return 0;
948 }
949
950 if (pmd_large(*pmdp)) {
951 paddr = pmd_val(*pmdp) & HPAGE_MASK;
952 paddr |= addr & ~HPAGE_MASK;
953 *key = page_get_storage_key(paddr);
954 spin_unlock(ptl);
955 return 0;
956 }
957 spin_unlock(ptl);
958
959 ptep = pte_alloc_map_lock(mm, pmdp, addr, &ptl);
960 if (unlikely(!ptep))
961 return -EFAULT;
962
963 pgste = pgste_get_lock(ptep);
964 *key = (pgste_val(pgste) & (PGSTE_ACC_BITS | PGSTE_FP_BIT)) >> 56;
965 paddr = pte_val(*ptep) & PAGE_MASK;
966 if (!(pte_val(*ptep) & _PAGE_INVALID))
967 *key = page_get_storage_key(paddr);
968 /* Reflect guest's logical view, not physical */
969 *key |= (pgste_val(pgste) & (PGSTE_GR_BIT | PGSTE_GC_BIT)) >> 48;
970 pgste_set_unlock(ptep, pgste);
971 pte_unmap_unlock(ptep, ptl);
972 return 0;
973 }
974 EXPORT_SYMBOL(get_guest_storage_key);
975
976 /**
977 * pgste_perform_essa - perform ESSA actions on the PGSTE.
978 * @mm: the memory context. It must have PGSTEs, no check is performed here!
979 * @hva: the host virtual address of the page whose PGSTE is to be processed
980 * @orc: the specific action to perform, see the ESSA_SET_* macros.
981 * @oldpte: the PTE will be saved there if the pointer is not NULL.
982 * @oldpgste: the old PGSTE will be saved there if the pointer is not NULL.
983 *
984 * Return: 1 if the page is to be added to the CBRL, otherwise 0,
985 * or < 0 in case of error. -EINVAL is returned for invalid values
986 * of orc, -EFAULT for invalid addresses.
987 */
pgste_perform_essa(struct mm_struct * mm,unsigned long hva,int orc,unsigned long * oldpte,unsigned long * oldpgste)988 int pgste_perform_essa(struct mm_struct *mm, unsigned long hva, int orc,
989 unsigned long *oldpte, unsigned long *oldpgste)
990 {
991 struct vm_area_struct *vma;
992 unsigned long pgstev;
993 spinlock_t *ptl;
994 pgste_t pgste;
995 pte_t *ptep;
996 int res = 0;
997
998 WARN_ON_ONCE(orc > ESSA_MAX);
999 if (unlikely(orc > ESSA_MAX))
1000 return -EINVAL;
1001
1002 vma = find_vma(mm, hva);
1003 if (!vma || hva < vma->vm_start || is_vm_hugetlb_page(vma))
1004 return -EFAULT;
1005 ptep = get_locked_pte(mm, hva, &ptl);
1006 if (unlikely(!ptep))
1007 return -EFAULT;
1008 pgste = pgste_get_lock(ptep);
1009 pgstev = pgste_val(pgste);
1010 if (oldpte)
1011 *oldpte = pte_val(*ptep);
1012 if (oldpgste)
1013 *oldpgste = pgstev;
1014
1015 switch (orc) {
1016 case ESSA_GET_STATE:
1017 break;
1018 case ESSA_SET_STABLE:
1019 pgstev &= ~(_PGSTE_GPS_USAGE_MASK | _PGSTE_GPS_NODAT);
1020 pgstev |= _PGSTE_GPS_USAGE_STABLE;
1021 break;
1022 case ESSA_SET_UNUSED:
1023 pgstev &= ~_PGSTE_GPS_USAGE_MASK;
1024 pgstev |= _PGSTE_GPS_USAGE_UNUSED;
1025 if (pte_val(*ptep) & _PAGE_INVALID)
1026 res = 1;
1027 break;
1028 case ESSA_SET_VOLATILE:
1029 pgstev &= ~_PGSTE_GPS_USAGE_MASK;
1030 pgstev |= _PGSTE_GPS_USAGE_VOLATILE;
1031 if (pte_val(*ptep) & _PAGE_INVALID)
1032 res = 1;
1033 break;
1034 case ESSA_SET_POT_VOLATILE:
1035 pgstev &= ~_PGSTE_GPS_USAGE_MASK;
1036 if (!(pte_val(*ptep) & _PAGE_INVALID)) {
1037 pgstev |= _PGSTE_GPS_USAGE_POT_VOLATILE;
1038 break;
1039 }
1040 if (pgstev & _PGSTE_GPS_ZERO) {
1041 pgstev |= _PGSTE_GPS_USAGE_VOLATILE;
1042 break;
1043 }
1044 if (!(pgstev & PGSTE_GC_BIT)) {
1045 pgstev |= _PGSTE_GPS_USAGE_VOLATILE;
1046 res = 1;
1047 break;
1048 }
1049 break;
1050 case ESSA_SET_STABLE_RESIDENT:
1051 pgstev &= ~_PGSTE_GPS_USAGE_MASK;
1052 pgstev |= _PGSTE_GPS_USAGE_STABLE;
1053 /*
1054 * Since the resident state can go away any time after this
1055 * call, we will not make this page resident. We can revisit
1056 * this decision if a guest will ever start using this.
1057 */
1058 break;
1059 case ESSA_SET_STABLE_IF_RESIDENT:
1060 if (!(pte_val(*ptep) & _PAGE_INVALID)) {
1061 pgstev &= ~_PGSTE_GPS_USAGE_MASK;
1062 pgstev |= _PGSTE_GPS_USAGE_STABLE;
1063 }
1064 break;
1065 case ESSA_SET_STABLE_NODAT:
1066 pgstev &= ~_PGSTE_GPS_USAGE_MASK;
1067 pgstev |= _PGSTE_GPS_USAGE_STABLE | _PGSTE_GPS_NODAT;
1068 break;
1069 default:
1070 /* we should never get here! */
1071 break;
1072 }
1073 /* If we are discarding a page, set it to logical zero */
1074 if (res)
1075 pgstev |= _PGSTE_GPS_ZERO;
1076
1077 pgste_val(pgste) = pgstev;
1078 pgste_set_unlock(ptep, pgste);
1079 pte_unmap_unlock(ptep, ptl);
1080 return res;
1081 }
1082 EXPORT_SYMBOL(pgste_perform_essa);
1083
1084 /**
1085 * set_pgste_bits - set specific PGSTE bits.
1086 * @mm: the memory context. It must have PGSTEs, no check is performed here!
1087 * @hva: the host virtual address of the page whose PGSTE is to be processed
1088 * @bits: a bitmask representing the bits that will be touched
1089 * @value: the values of the bits to be written. Only the bits in the mask
1090 * will be written.
1091 *
1092 * Return: 0 on success, < 0 in case of error.
1093 */
set_pgste_bits(struct mm_struct * mm,unsigned long hva,unsigned long bits,unsigned long value)1094 int set_pgste_bits(struct mm_struct *mm, unsigned long hva,
1095 unsigned long bits, unsigned long value)
1096 {
1097 struct vm_area_struct *vma;
1098 spinlock_t *ptl;
1099 pgste_t new;
1100 pte_t *ptep;
1101
1102 vma = find_vma(mm, hva);
1103 if (!vma || hva < vma->vm_start || is_vm_hugetlb_page(vma))
1104 return -EFAULT;
1105 ptep = get_locked_pte(mm, hva, &ptl);
1106 if (unlikely(!ptep))
1107 return -EFAULT;
1108 new = pgste_get_lock(ptep);
1109
1110 pgste_val(new) &= ~bits;
1111 pgste_val(new) |= value & bits;
1112
1113 pgste_set_unlock(ptep, new);
1114 pte_unmap_unlock(ptep, ptl);
1115 return 0;
1116 }
1117 EXPORT_SYMBOL(set_pgste_bits);
1118
1119 /**
1120 * get_pgste - get the current PGSTE for the given address.
1121 * @mm: the memory context. It must have PGSTEs, no check is performed here!
1122 * @hva: the host virtual address of the page whose PGSTE is to be processed
1123 * @pgstep: will be written with the current PGSTE for the given address.
1124 *
1125 * Return: 0 on success, < 0 in case of error.
1126 */
get_pgste(struct mm_struct * mm,unsigned long hva,unsigned long * pgstep)1127 int get_pgste(struct mm_struct *mm, unsigned long hva, unsigned long *pgstep)
1128 {
1129 struct vm_area_struct *vma;
1130 spinlock_t *ptl;
1131 pte_t *ptep;
1132
1133 vma = find_vma(mm, hva);
1134 if (!vma || hva < vma->vm_start || is_vm_hugetlb_page(vma))
1135 return -EFAULT;
1136 ptep = get_locked_pte(mm, hva, &ptl);
1137 if (unlikely(!ptep))
1138 return -EFAULT;
1139 *pgstep = pgste_val(pgste_get(ptep));
1140 pte_unmap_unlock(ptep, ptl);
1141 return 0;
1142 }
1143 EXPORT_SYMBOL(get_pgste);
1144 #endif
1145