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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
27pgprot_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}
35EXPORT_SYMBOL_GPL(pgprot_writecombine);
36
37pgprot_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}
45EXPORT_SYMBOL_GPL(pgprot_writethrough);
46
47static 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
67static 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
87static 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
106static 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 set_pte(ptep, set_pte_bit(*ptep, __pgprot(_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
126static 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
145static 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
157static 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
166static 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
173static 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
194static 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
216static 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 entry = set_pte_bit(entry, __pgprot(_PAGE_DIRTY));
228 entry = clear_pte_bit(entry, __pgprot(_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 set_pte(ptep, entry);
236 return pgste;
237}
238
239static 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
255static 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
267static 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 old = set_pte_bit(old, __pgprot(_PAGE_UNUSED));
279 }
280 pgste = pgste_set_pte(ptep, pgste, new);
281 pgste_set_unlock(ptep, pgste);
282 } else {
283 set_pte(ptep, new);
284 }
285 return old;
286}
287
288pte_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}
303EXPORT_SYMBOL(ptep_xchg_direct);
304
305pte_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}
320EXPORT_SYMBOL(ptep_xchg_lazy);
321
322pte_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
341void 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 = clear_pte_bit(pte, __pgprot(_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 set_pte(ptep, pte);
356 }
357 preempt_enable();
358}
359
360static 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
372static 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
391static 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
409static 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 set_pmd(pmdp, set_pmd_bit(*pmdp, __pgprot(_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
432static int pmd_lookup(struct mm_struct *mm, unsigned long addr, pmd_t **pmdp)
433{
434 struct vm_area_struct *vma;
435 pgd_t *pgd;
436 p4d_t *p4d;
437 pud_t *pud;
438
439 /* We need a valid VMA, otherwise this is clearly a fault. */
440 vma = vma_lookup(mm, addr);
441 if (!vma)
442 return -EFAULT;
443
444 pgd = pgd_offset(mm, addr);
445 if (!pgd_present(*pgd))
446 return -ENOENT;
447
448 p4d = p4d_offset(pgd, addr);
449 if (!p4d_present(*p4d))
450 return -ENOENT;
451
452 pud = pud_offset(p4d, addr);
453 if (!pud_present(*pud))
454 return -ENOENT;
455
456 /* Large PUDs are not supported yet. */
457 if (pud_large(*pud))
458 return -EFAULT;
459
460 *pmdp = pmd_offset(pud, addr);
461 return 0;
462}
463#endif
464
465pmd_t pmdp_xchg_direct(struct mm_struct *mm, unsigned long addr,
466 pmd_t *pmdp, pmd_t new)
467{
468 pmd_t old;
469
470 preempt_disable();
471 old = pmdp_flush_direct(mm, addr, pmdp);
472 set_pmd(pmdp, new);
473 preempt_enable();
474 return old;
475}
476EXPORT_SYMBOL(pmdp_xchg_direct);
477
478pmd_t pmdp_xchg_lazy(struct mm_struct *mm, unsigned long addr,
479 pmd_t *pmdp, pmd_t new)
480{
481 pmd_t old;
482
483 preempt_disable();
484 old = pmdp_flush_lazy(mm, addr, pmdp);
485 set_pmd(pmdp, new);
486 preempt_enable();
487 return old;
488}
489EXPORT_SYMBOL(pmdp_xchg_lazy);
490
491static inline void pudp_idte_local(struct mm_struct *mm,
492 unsigned long addr, pud_t *pudp)
493{
494 if (MACHINE_HAS_TLB_GUEST)
495 __pudp_idte(addr, pudp, IDTE_NODAT | IDTE_GUEST_ASCE,
496 mm->context.asce, IDTE_LOCAL);
497 else
498 __pudp_idte(addr, pudp, 0, 0, IDTE_LOCAL);
499}
500
501static inline void pudp_idte_global(struct mm_struct *mm,
502 unsigned long addr, pud_t *pudp)
503{
504 if (MACHINE_HAS_TLB_GUEST)
505 __pudp_idte(addr, pudp, IDTE_NODAT | IDTE_GUEST_ASCE,
506 mm->context.asce, IDTE_GLOBAL);
507 else if (MACHINE_HAS_IDTE)
508 __pudp_idte(addr, pudp, 0, 0, IDTE_GLOBAL);
509 else
510 /*
511 * Invalid bit position is the same for pmd and pud, so we can
512 * re-use _pmd_csp() here
513 */
514 __pmdp_csp((pmd_t *) pudp);
515}
516
517static inline pud_t pudp_flush_direct(struct mm_struct *mm,
518 unsigned long addr, pud_t *pudp)
519{
520 pud_t old;
521
522 old = *pudp;
523 if (pud_val(old) & _REGION_ENTRY_INVALID)
524 return old;
525 atomic_inc(&mm->context.flush_count);
526 if (MACHINE_HAS_TLB_LC &&
527 cpumask_equal(mm_cpumask(mm), cpumask_of(smp_processor_id())))
528 pudp_idte_local(mm, addr, pudp);
529 else
530 pudp_idte_global(mm, addr, pudp);
531 atomic_dec(&mm->context.flush_count);
532 return old;
533}
534
535pud_t pudp_xchg_direct(struct mm_struct *mm, unsigned long addr,
536 pud_t *pudp, pud_t new)
537{
538 pud_t old;
539
540 preempt_disable();
541 old = pudp_flush_direct(mm, addr, pudp);
542 set_pud(pudp, new);
543 preempt_enable();
544 return old;
545}
546EXPORT_SYMBOL(pudp_xchg_direct);
547
548#ifdef CONFIG_TRANSPARENT_HUGEPAGE
549void pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp,
550 pgtable_t pgtable)
551{
552 struct list_head *lh = (struct list_head *) pgtable;
553
554 assert_spin_locked(pmd_lockptr(mm, pmdp));
555
556 /* FIFO */
557 if (!pmd_huge_pte(mm, pmdp))
558 INIT_LIST_HEAD(lh);
559 else
560 list_add(lh, (struct list_head *) pmd_huge_pte(mm, pmdp));
561 pmd_huge_pte(mm, pmdp) = pgtable;
562}
563
564pgtable_t pgtable_trans_huge_withdraw(struct mm_struct *mm, pmd_t *pmdp)
565{
566 struct list_head *lh;
567 pgtable_t pgtable;
568 pte_t *ptep;
569
570 assert_spin_locked(pmd_lockptr(mm, pmdp));
571
572 /* FIFO */
573 pgtable = pmd_huge_pte(mm, pmdp);
574 lh = (struct list_head *) pgtable;
575 if (list_empty(lh))
576 pmd_huge_pte(mm, pmdp) = NULL;
577 else {
578 pmd_huge_pte(mm, pmdp) = (pgtable_t) lh->next;
579 list_del(lh);
580 }
581 ptep = (pte_t *) pgtable;
582 set_pte(ptep, __pte(_PAGE_INVALID));
583 ptep++;
584 set_pte(ptep, __pte(_PAGE_INVALID));
585 return pgtable;
586}
587#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
588
589#ifdef CONFIG_PGSTE
590void ptep_set_pte_at(struct mm_struct *mm, unsigned long addr,
591 pte_t *ptep, pte_t entry)
592{
593 pgste_t pgste;
594
595 /* the mm_has_pgste() check is done in set_pte_at() */
596 preempt_disable();
597 pgste = pgste_get_lock(ptep);
598 pgste_val(pgste) &= ~_PGSTE_GPS_ZERO;
599 pgste_set_key(ptep, pgste, entry, mm);
600 pgste = pgste_set_pte(ptep, pgste, entry);
601 pgste_set_unlock(ptep, pgste);
602 preempt_enable();
603}
604
605void ptep_set_notify(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
606{
607 pgste_t pgste;
608
609 preempt_disable();
610 pgste = pgste_get_lock(ptep);
611 pgste_val(pgste) |= PGSTE_IN_BIT;
612 pgste_set_unlock(ptep, pgste);
613 preempt_enable();
614}
615
616/**
617 * ptep_force_prot - change access rights of a locked pte
618 * @mm: pointer to the process mm_struct
619 * @addr: virtual address in the guest address space
620 * @ptep: pointer to the page table entry
621 * @prot: indicates guest access rights: PROT_NONE, PROT_READ or PROT_WRITE
622 * @bit: pgste bit to set (e.g. for notification)
623 *
624 * Returns 0 if the access rights were changed and -EAGAIN if the current
625 * and requested access rights are incompatible.
626 */
627int ptep_force_prot(struct mm_struct *mm, unsigned long addr,
628 pte_t *ptep, int prot, unsigned long bit)
629{
630 pte_t entry;
631 pgste_t pgste;
632 int pte_i, pte_p, nodat;
633
634 pgste = pgste_get_lock(ptep);
635 entry = *ptep;
636 /* Check pte entry after all locks have been acquired */
637 pte_i = pte_val(entry) & _PAGE_INVALID;
638 pte_p = pte_val(entry) & _PAGE_PROTECT;
639 if ((pte_i && (prot != PROT_NONE)) ||
640 (pte_p && (prot & PROT_WRITE))) {
641 pgste_set_unlock(ptep, pgste);
642 return -EAGAIN;
643 }
644 /* Change access rights and set pgste bit */
645 nodat = !!(pgste_val(pgste) & _PGSTE_GPS_NODAT);
646 if (prot == PROT_NONE && !pte_i) {
647 ptep_flush_direct(mm, addr, ptep, nodat);
648 pgste = pgste_update_all(entry, pgste, mm);
649 entry = set_pte_bit(entry, __pgprot(_PAGE_INVALID));
650 }
651 if (prot == PROT_READ && !pte_p) {
652 ptep_flush_direct(mm, addr, ptep, nodat);
653 entry = clear_pte_bit(entry, __pgprot(_PAGE_INVALID));
654 entry = set_pte_bit(entry, __pgprot(_PAGE_PROTECT));
655 }
656 pgste_val(pgste) |= bit;
657 pgste = pgste_set_pte(ptep, pgste, entry);
658 pgste_set_unlock(ptep, pgste);
659 return 0;
660}
661
662int ptep_shadow_pte(struct mm_struct *mm, unsigned long saddr,
663 pte_t *sptep, pte_t *tptep, pte_t pte)
664{
665 pgste_t spgste, tpgste;
666 pte_t spte, tpte;
667 int rc = -EAGAIN;
668
669 if (!(pte_val(*tptep) & _PAGE_INVALID))
670 return 0; /* already shadowed */
671 spgste = pgste_get_lock(sptep);
672 spte = *sptep;
673 if (!(pte_val(spte) & _PAGE_INVALID) &&
674 !((pte_val(spte) & _PAGE_PROTECT) &&
675 !(pte_val(pte) & _PAGE_PROTECT))) {
676 pgste_val(spgste) |= PGSTE_VSIE_BIT;
677 tpgste = pgste_get_lock(tptep);
678 tpte = __pte((pte_val(spte) & PAGE_MASK) |
679 (pte_val(pte) & _PAGE_PROTECT));
680 /* don't touch the storage key - it belongs to parent pgste */
681 tpgste = pgste_set_pte(tptep, tpgste, tpte);
682 pgste_set_unlock(tptep, tpgste);
683 rc = 1;
684 }
685 pgste_set_unlock(sptep, spgste);
686 return rc;
687}
688
689void ptep_unshadow_pte(struct mm_struct *mm, unsigned long saddr, pte_t *ptep)
690{
691 pgste_t pgste;
692 int nodat;
693
694 pgste = pgste_get_lock(ptep);
695 /* notifier is called by the caller */
696 nodat = !!(pgste_val(pgste) & _PGSTE_GPS_NODAT);
697 ptep_flush_direct(mm, saddr, ptep, nodat);
698 /* don't touch the storage key - it belongs to parent pgste */
699 pgste = pgste_set_pte(ptep, pgste, __pte(_PAGE_INVALID));
700 pgste_set_unlock(ptep, pgste);
701}
702
703static void ptep_zap_swap_entry(struct mm_struct *mm, swp_entry_t entry)
704{
705 if (!non_swap_entry(entry))
706 dec_mm_counter(mm, MM_SWAPENTS);
707 else if (is_migration_entry(entry)) {
708 struct page *page = pfn_swap_entry_to_page(entry);
709
710 dec_mm_counter(mm, mm_counter(page));
711 }
712 free_swap_and_cache(entry);
713}
714
715void ptep_zap_unused(struct mm_struct *mm, unsigned long addr,
716 pte_t *ptep, int reset)
717{
718 unsigned long pgstev;
719 pgste_t pgste;
720 pte_t pte;
721
722 /* Zap unused and logically-zero pages */
723 preempt_disable();
724 pgste = pgste_get_lock(ptep);
725 pgstev = pgste_val(pgste);
726 pte = *ptep;
727 if (!reset && pte_swap(pte) &&
728 ((pgstev & _PGSTE_GPS_USAGE_MASK) == _PGSTE_GPS_USAGE_UNUSED ||
729 (pgstev & _PGSTE_GPS_ZERO))) {
730 ptep_zap_swap_entry(mm, pte_to_swp_entry(pte));
731 pte_clear(mm, addr, ptep);
732 }
733 if (reset)
734 pgste_val(pgste) &= ~_PGSTE_GPS_USAGE_MASK;
735 pgste_set_unlock(ptep, pgste);
736 preempt_enable();
737}
738
739void ptep_zap_key(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
740{
741 unsigned long ptev;
742 pgste_t pgste;
743
744 /* Clear storage key ACC and F, but set R/C */
745 preempt_disable();
746 pgste = pgste_get_lock(ptep);
747 pgste_val(pgste) &= ~(PGSTE_ACC_BITS | PGSTE_FP_BIT);
748 pgste_val(pgste) |= PGSTE_GR_BIT | PGSTE_GC_BIT;
749 ptev = pte_val(*ptep);
750 if (!(ptev & _PAGE_INVALID) && (ptev & _PAGE_WRITE))
751 page_set_storage_key(ptev & PAGE_MASK, PAGE_DEFAULT_KEY, 0);
752 pgste_set_unlock(ptep, pgste);
753 preempt_enable();
754}
755
756/*
757 * Test and reset if a guest page is dirty
758 */
759bool ptep_test_and_clear_uc(struct mm_struct *mm, unsigned long addr,
760 pte_t *ptep)
761{
762 pgste_t pgste;
763 pte_t pte;
764 bool dirty;
765 int nodat;
766
767 pgste = pgste_get_lock(ptep);
768 dirty = !!(pgste_val(pgste) & PGSTE_UC_BIT);
769 pgste_val(pgste) &= ~PGSTE_UC_BIT;
770 pte = *ptep;
771 if (dirty && (pte_val(pte) & _PAGE_PRESENT)) {
772 pgste = pgste_pte_notify(mm, addr, ptep, pgste);
773 nodat = !!(pgste_val(pgste) & _PGSTE_GPS_NODAT);
774 ptep_ipte_global(mm, addr, ptep, nodat);
775 if (MACHINE_HAS_ESOP || !(pte_val(pte) & _PAGE_WRITE))
776 pte = set_pte_bit(pte, __pgprot(_PAGE_PROTECT));
777 else
778 pte = set_pte_bit(pte, __pgprot(_PAGE_INVALID));
779 set_pte(ptep, pte);
780 }
781 pgste_set_unlock(ptep, pgste);
782 return dirty;
783}
784EXPORT_SYMBOL_GPL(ptep_test_and_clear_uc);
785
786int set_guest_storage_key(struct mm_struct *mm, unsigned long addr,
787 unsigned char key, bool nq)
788{
789 unsigned long keyul, paddr;
790 spinlock_t *ptl;
791 pgste_t old, new;
792 pmd_t *pmdp;
793 pte_t *ptep;
794
795 /*
796 * If we don't have a PTE table and if there is no huge page mapped,
797 * we can ignore attempts to set the key to 0, because it already is 0.
798 */
799 switch (pmd_lookup(mm, addr, &pmdp)) {
800 case -ENOENT:
801 return key ? -EFAULT : 0;
802 case 0:
803 break;
804 default:
805 return -EFAULT;
806 }
807
808 ptl = pmd_lock(mm, pmdp);
809 if (!pmd_present(*pmdp)) {
810 spin_unlock(ptl);
811 return key ? -EFAULT : 0;
812 }
813
814 if (pmd_large(*pmdp)) {
815 paddr = pmd_val(*pmdp) & HPAGE_MASK;
816 paddr |= addr & ~HPAGE_MASK;
817 /*
818 * Huge pmds need quiescing operations, they are
819 * always mapped.
820 */
821 page_set_storage_key(paddr, key, 1);
822 spin_unlock(ptl);
823 return 0;
824 }
825 spin_unlock(ptl);
826
827 ptep = pte_offset_map_lock(mm, pmdp, addr, &ptl);
828 new = old = pgste_get_lock(ptep);
829 pgste_val(new) &= ~(PGSTE_GR_BIT | PGSTE_GC_BIT |
830 PGSTE_ACC_BITS | PGSTE_FP_BIT);
831 keyul = (unsigned long) key;
832 pgste_val(new) |= (keyul & (_PAGE_CHANGED | _PAGE_REFERENCED)) << 48;
833 pgste_val(new) |= (keyul & (_PAGE_ACC_BITS | _PAGE_FP_BIT)) << 56;
834 if (!(pte_val(*ptep) & _PAGE_INVALID)) {
835 unsigned long bits, skey;
836
837 paddr = pte_val(*ptep) & PAGE_MASK;
838 skey = (unsigned long) page_get_storage_key(paddr);
839 bits = skey & (_PAGE_CHANGED | _PAGE_REFERENCED);
840 skey = key & (_PAGE_ACC_BITS | _PAGE_FP_BIT);
841 /* Set storage key ACC and FP */
842 page_set_storage_key(paddr, skey, !nq);
843 /* Merge host changed & referenced into pgste */
844 pgste_val(new) |= bits << 52;
845 }
846 /* changing the guest storage key is considered a change of the page */
847 if ((pgste_val(new) ^ pgste_val(old)) &
848 (PGSTE_ACC_BITS | PGSTE_FP_BIT | PGSTE_GR_BIT | PGSTE_GC_BIT))
849 pgste_val(new) |= PGSTE_UC_BIT;
850
851 pgste_set_unlock(ptep, new);
852 pte_unmap_unlock(ptep, ptl);
853 return 0;
854}
855EXPORT_SYMBOL(set_guest_storage_key);
856
857/*
858 * Conditionally set a guest storage key (handling csske).
859 * oldkey will be updated when either mr or mc is set and a pointer is given.
860 *
861 * Returns 0 if a guests storage key update wasn't necessary, 1 if the guest
862 * storage key was updated and -EFAULT on access errors.
863 */
864int cond_set_guest_storage_key(struct mm_struct *mm, unsigned long addr,
865 unsigned char key, unsigned char *oldkey,
866 bool nq, bool mr, bool mc)
867{
868 unsigned char tmp, mask = _PAGE_ACC_BITS | _PAGE_FP_BIT;
869 int rc;
870
871 /* we can drop the pgste lock between getting and setting the key */
872 if (mr | mc) {
873 rc = get_guest_storage_key(current->mm, addr, &tmp);
874 if (rc)
875 return rc;
876 if (oldkey)
877 *oldkey = tmp;
878 if (!mr)
879 mask |= _PAGE_REFERENCED;
880 if (!mc)
881 mask |= _PAGE_CHANGED;
882 if (!((tmp ^ key) & mask))
883 return 0;
884 }
885 rc = set_guest_storage_key(current->mm, addr, key, nq);
886 return rc < 0 ? rc : 1;
887}
888EXPORT_SYMBOL(cond_set_guest_storage_key);
889
890/*
891 * Reset a guest reference bit (rrbe), returning the reference and changed bit.
892 *
893 * Returns < 0 in case of error, otherwise the cc to be reported to the guest.
894 */
895int reset_guest_reference_bit(struct mm_struct *mm, unsigned long addr)
896{
897 spinlock_t *ptl;
898 unsigned long paddr;
899 pgste_t old, new;
900 pmd_t *pmdp;
901 pte_t *ptep;
902 int cc = 0;
903
904 /*
905 * If we don't have a PTE table and if there is no huge page mapped,
906 * the storage key is 0 and there is nothing for us to do.
907 */
908 switch (pmd_lookup(mm, addr, &pmdp)) {
909 case -ENOENT:
910 return 0;
911 case 0:
912 break;
913 default:
914 return -EFAULT;
915 }
916
917 ptl = pmd_lock(mm, pmdp);
918 if (!pmd_present(*pmdp)) {
919 spin_unlock(ptl);
920 return 0;
921 }
922
923 if (pmd_large(*pmdp)) {
924 paddr = pmd_val(*pmdp) & HPAGE_MASK;
925 paddr |= addr & ~HPAGE_MASK;
926 cc = page_reset_referenced(paddr);
927 spin_unlock(ptl);
928 return cc;
929 }
930 spin_unlock(ptl);
931
932 ptep = pte_offset_map_lock(mm, pmdp, addr, &ptl);
933 new = old = pgste_get_lock(ptep);
934 /* Reset guest reference bit only */
935 pgste_val(new) &= ~PGSTE_GR_BIT;
936
937 if (!(pte_val(*ptep) & _PAGE_INVALID)) {
938 paddr = pte_val(*ptep) & PAGE_MASK;
939 cc = page_reset_referenced(paddr);
940 /* Merge real referenced bit into host-set */
941 pgste_val(new) |= ((unsigned long) cc << 53) & PGSTE_HR_BIT;
942 }
943 /* Reflect guest's logical view, not physical */
944 cc |= (pgste_val(old) & (PGSTE_GR_BIT | PGSTE_GC_BIT)) >> 49;
945 /* Changing the guest storage key is considered a change of the page */
946 if ((pgste_val(new) ^ pgste_val(old)) & PGSTE_GR_BIT)
947 pgste_val(new) |= PGSTE_UC_BIT;
948
949 pgste_set_unlock(ptep, new);
950 pte_unmap_unlock(ptep, ptl);
951 return cc;
952}
953EXPORT_SYMBOL(reset_guest_reference_bit);
954
955int get_guest_storage_key(struct mm_struct *mm, unsigned long addr,
956 unsigned char *key)
957{
958 unsigned long paddr;
959 spinlock_t *ptl;
960 pgste_t pgste;
961 pmd_t *pmdp;
962 pte_t *ptep;
963
964 /*
965 * If we don't have a PTE table and if there is no huge page mapped,
966 * the storage key is 0.
967 */
968 *key = 0;
969
970 switch (pmd_lookup(mm, addr, &pmdp)) {
971 case -ENOENT:
972 return 0;
973 case 0:
974 break;
975 default:
976 return -EFAULT;
977 }
978
979 ptl = pmd_lock(mm, pmdp);
980 if (!pmd_present(*pmdp)) {
981 spin_unlock(ptl);
982 return 0;
983 }
984
985 if (pmd_large(*pmdp)) {
986 paddr = pmd_val(*pmdp) & HPAGE_MASK;
987 paddr |= addr & ~HPAGE_MASK;
988 *key = page_get_storage_key(paddr);
989 spin_unlock(ptl);
990 return 0;
991 }
992 spin_unlock(ptl);
993
994 ptep = pte_offset_map_lock(mm, pmdp, addr, &ptl);
995 pgste = pgste_get_lock(ptep);
996 *key = (pgste_val(pgste) & (PGSTE_ACC_BITS | PGSTE_FP_BIT)) >> 56;
997 paddr = pte_val(*ptep) & PAGE_MASK;
998 if (!(pte_val(*ptep) & _PAGE_INVALID))
999 *key = page_get_storage_key(paddr);
1000 /* Reflect guest's logical view, not physical */
1001 *key |= (pgste_val(pgste) & (PGSTE_GR_BIT | PGSTE_GC_BIT)) >> 48;
1002 pgste_set_unlock(ptep, pgste);
1003 pte_unmap_unlock(ptep, ptl);
1004 return 0;
1005}
1006EXPORT_SYMBOL(get_guest_storage_key);
1007
1008/**
1009 * pgste_perform_essa - perform ESSA actions on the PGSTE.
1010 * @mm: the memory context. It must have PGSTEs, no check is performed here!
1011 * @hva: the host virtual address of the page whose PGSTE is to be processed
1012 * @orc: the specific action to perform, see the ESSA_SET_* macros.
1013 * @oldpte: the PTE will be saved there if the pointer is not NULL.
1014 * @oldpgste: the old PGSTE will be saved there if the pointer is not NULL.
1015 *
1016 * Return: 1 if the page is to be added to the CBRL, otherwise 0,
1017 * or < 0 in case of error. -EINVAL is returned for invalid values
1018 * of orc, -EFAULT for invalid addresses.
1019 */
1020int pgste_perform_essa(struct mm_struct *mm, unsigned long hva, int orc,
1021 unsigned long *oldpte, unsigned long *oldpgste)
1022{
1023 struct vm_area_struct *vma;
1024 unsigned long pgstev;
1025 spinlock_t *ptl;
1026 pgste_t pgste;
1027 pte_t *ptep;
1028 int res = 0;
1029
1030 WARN_ON_ONCE(orc > ESSA_MAX);
1031 if (unlikely(orc > ESSA_MAX))
1032 return -EINVAL;
1033
1034 vma = vma_lookup(mm, hva);
1035 if (!vma || is_vm_hugetlb_page(vma))
1036 return -EFAULT;
1037 ptep = get_locked_pte(mm, hva, &ptl);
1038 if (unlikely(!ptep))
1039 return -EFAULT;
1040 pgste = pgste_get_lock(ptep);
1041 pgstev = pgste_val(pgste);
1042 if (oldpte)
1043 *oldpte = pte_val(*ptep);
1044 if (oldpgste)
1045 *oldpgste = pgstev;
1046
1047 switch (orc) {
1048 case ESSA_GET_STATE:
1049 break;
1050 case ESSA_SET_STABLE:
1051 pgstev &= ~(_PGSTE_GPS_USAGE_MASK | _PGSTE_GPS_NODAT);
1052 pgstev |= _PGSTE_GPS_USAGE_STABLE;
1053 break;
1054 case ESSA_SET_UNUSED:
1055 pgstev &= ~_PGSTE_GPS_USAGE_MASK;
1056 pgstev |= _PGSTE_GPS_USAGE_UNUSED;
1057 if (pte_val(*ptep) & _PAGE_INVALID)
1058 res = 1;
1059 break;
1060 case ESSA_SET_VOLATILE:
1061 pgstev &= ~_PGSTE_GPS_USAGE_MASK;
1062 pgstev |= _PGSTE_GPS_USAGE_VOLATILE;
1063 if (pte_val(*ptep) & _PAGE_INVALID)
1064 res = 1;
1065 break;
1066 case ESSA_SET_POT_VOLATILE:
1067 pgstev &= ~_PGSTE_GPS_USAGE_MASK;
1068 if (!(pte_val(*ptep) & _PAGE_INVALID)) {
1069 pgstev |= _PGSTE_GPS_USAGE_POT_VOLATILE;
1070 break;
1071 }
1072 if (pgstev & _PGSTE_GPS_ZERO) {
1073 pgstev |= _PGSTE_GPS_USAGE_VOLATILE;
1074 break;
1075 }
1076 if (!(pgstev & PGSTE_GC_BIT)) {
1077 pgstev |= _PGSTE_GPS_USAGE_VOLATILE;
1078 res = 1;
1079 break;
1080 }
1081 break;
1082 case ESSA_SET_STABLE_RESIDENT:
1083 pgstev &= ~_PGSTE_GPS_USAGE_MASK;
1084 pgstev |= _PGSTE_GPS_USAGE_STABLE;
1085 /*
1086 * Since the resident state can go away any time after this
1087 * call, we will not make this page resident. We can revisit
1088 * this decision if a guest will ever start using this.
1089 */
1090 break;
1091 case ESSA_SET_STABLE_IF_RESIDENT:
1092 if (!(pte_val(*ptep) & _PAGE_INVALID)) {
1093 pgstev &= ~_PGSTE_GPS_USAGE_MASK;
1094 pgstev |= _PGSTE_GPS_USAGE_STABLE;
1095 }
1096 break;
1097 case ESSA_SET_STABLE_NODAT:
1098 pgstev &= ~_PGSTE_GPS_USAGE_MASK;
1099 pgstev |= _PGSTE_GPS_USAGE_STABLE | _PGSTE_GPS_NODAT;
1100 break;
1101 default:
1102 /* we should never get here! */
1103 break;
1104 }
1105 /* If we are discarding a page, set it to logical zero */
1106 if (res)
1107 pgstev |= _PGSTE_GPS_ZERO;
1108
1109 pgste_val(pgste) = pgstev;
1110 pgste_set_unlock(ptep, pgste);
1111 pte_unmap_unlock(ptep, ptl);
1112 return res;
1113}
1114EXPORT_SYMBOL(pgste_perform_essa);
1115
1116/**
1117 * set_pgste_bits - set specific PGSTE bits.
1118 * @mm: the memory context. It must have PGSTEs, no check is performed here!
1119 * @hva: the host virtual address of the page whose PGSTE is to be processed
1120 * @bits: a bitmask representing the bits that will be touched
1121 * @value: the values of the bits to be written. Only the bits in the mask
1122 * will be written.
1123 *
1124 * Return: 0 on success, < 0 in case of error.
1125 */
1126int set_pgste_bits(struct mm_struct *mm, unsigned long hva,
1127 unsigned long bits, unsigned long value)
1128{
1129 struct vm_area_struct *vma;
1130 spinlock_t *ptl;
1131 pgste_t new;
1132 pte_t *ptep;
1133
1134 vma = vma_lookup(mm, hva);
1135 if (!vma || is_vm_hugetlb_page(vma))
1136 return -EFAULT;
1137 ptep = get_locked_pte(mm, hva, &ptl);
1138 if (unlikely(!ptep))
1139 return -EFAULT;
1140 new = pgste_get_lock(ptep);
1141
1142 pgste_val(new) &= ~bits;
1143 pgste_val(new) |= value & bits;
1144
1145 pgste_set_unlock(ptep, new);
1146 pte_unmap_unlock(ptep, ptl);
1147 return 0;
1148}
1149EXPORT_SYMBOL(set_pgste_bits);
1150
1151/**
1152 * get_pgste - get the current PGSTE for the given address.
1153 * @mm: the memory context. It must have PGSTEs, no check is performed here!
1154 * @hva: the host virtual address of the page whose PGSTE is to be processed
1155 * @pgstep: will be written with the current PGSTE for the given address.
1156 *
1157 * Return: 0 on success, < 0 in case of error.
1158 */
1159int get_pgste(struct mm_struct *mm, unsigned long hva, unsigned long *pgstep)
1160{
1161 struct vm_area_struct *vma;
1162 spinlock_t *ptl;
1163 pte_t *ptep;
1164
1165 vma = vma_lookup(mm, hva);
1166 if (!vma || is_vm_hugetlb_page(vma))
1167 return -EFAULT;
1168 ptep = get_locked_pte(mm, hva, &ptl);
1169 if (unlikely(!ptep))
1170 return -EFAULT;
1171 *pgstep = pgste_val(pgste_get(ptep));
1172 pte_unmap_unlock(ptep, ptl);
1173 return 0;
1174}
1175EXPORT_SYMBOL(get_pgste);
1176#endif
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
27static inline void ptep_ipte_local(struct mm_struct *mm, unsigned long addr,
28 pte_t *ptep, int nodat)
29{
30 unsigned long opt, asce;
31
32 if (MACHINE_HAS_TLB_GUEST) {
33 opt = 0;
34 asce = READ_ONCE(mm->context.gmap_asce);
35 if (asce == 0UL || nodat)
36 opt |= IPTE_NODAT;
37 if (asce != -1UL) {
38 asce = asce ? : mm->context.asce;
39 opt |= IPTE_GUEST_ASCE;
40 }
41 __ptep_ipte(addr, ptep, opt, asce, IPTE_LOCAL);
42 } else {
43 __ptep_ipte(addr, ptep, 0, 0, IPTE_LOCAL);
44 }
45}
46
47static inline void ptep_ipte_global(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_GLOBAL);
62 } else {
63 __ptep_ipte(addr, ptep, 0, 0, IPTE_GLOBAL);
64 }
65}
66
67static inline pte_t ptep_flush_direct(struct mm_struct *mm,
68 unsigned long addr, pte_t *ptep,
69 int nodat)
70{
71 pte_t old;
72
73 old = *ptep;
74 if (unlikely(pte_val(old) & _PAGE_INVALID))
75 return old;
76 atomic_inc(&mm->context.flush_count);
77 if (MACHINE_HAS_TLB_LC &&
78 cpumask_equal(mm_cpumask(mm), cpumask_of(smp_processor_id())))
79 ptep_ipte_local(mm, addr, ptep, nodat);
80 else
81 ptep_ipte_global(mm, addr, ptep, nodat);
82 atomic_dec(&mm->context.flush_count);
83 return old;
84}
85
86static inline pte_t ptep_flush_lazy(struct mm_struct *mm,
87 unsigned long addr, pte_t *ptep,
88 int nodat)
89{
90 pte_t old;
91
92 old = *ptep;
93 if (unlikely(pte_val(old) & _PAGE_INVALID))
94 return old;
95 atomic_inc(&mm->context.flush_count);
96 if (cpumask_equal(&mm->context.cpu_attach_mask,
97 cpumask_of(smp_processor_id()))) {
98 pte_val(*ptep) |= _PAGE_INVALID;
99 mm->context.flush_mm = 1;
100 } else
101 ptep_ipte_global(mm, addr, ptep, nodat);
102 atomic_dec(&mm->context.flush_count);
103 return old;
104}
105
106static inline pgste_t pgste_get_lock(pte_t *ptep)
107{
108 unsigned long new = 0;
109#ifdef CONFIG_PGSTE
110 unsigned long old;
111
112 asm(
113 " lg %0,%2\n"
114 "0: lgr %1,%0\n"
115 " nihh %0,0xff7f\n" /* clear PCL bit in old */
116 " oihh %1,0x0080\n" /* set PCL bit in new */
117 " csg %0,%1,%2\n"
118 " jl 0b\n"
119 : "=&d" (old), "=&d" (new), "=Q" (ptep[PTRS_PER_PTE])
120 : "Q" (ptep[PTRS_PER_PTE]) : "cc", "memory");
121#endif
122 return __pgste(new);
123}
124
125static inline void pgste_set_unlock(pte_t *ptep, pgste_t pgste)
126{
127#ifdef CONFIG_PGSTE
128 asm(
129 " nihh %1,0xff7f\n" /* clear PCL bit */
130 " stg %1,%0\n"
131 : "=Q" (ptep[PTRS_PER_PTE])
132 : "d" (pgste_val(pgste)), "Q" (ptep[PTRS_PER_PTE])
133 : "cc", "memory");
134#endif
135}
136
137static inline pgste_t pgste_get(pte_t *ptep)
138{
139 unsigned long pgste = 0;
140#ifdef CONFIG_PGSTE
141 pgste = *(unsigned long *)(ptep + PTRS_PER_PTE);
142#endif
143 return __pgste(pgste);
144}
145
146static inline void pgste_set(pte_t *ptep, pgste_t pgste)
147{
148#ifdef CONFIG_PGSTE
149 *(pgste_t *)(ptep + PTRS_PER_PTE) = pgste;
150#endif
151}
152
153static inline pgste_t pgste_update_all(pte_t pte, pgste_t pgste,
154 struct mm_struct *mm)
155{
156#ifdef CONFIG_PGSTE
157 unsigned long address, bits, skey;
158
159 if (!mm_uses_skeys(mm) || pte_val(pte) & _PAGE_INVALID)
160 return pgste;
161 address = pte_val(pte) & PAGE_MASK;
162 skey = (unsigned long) page_get_storage_key(address);
163 bits = skey & (_PAGE_CHANGED | _PAGE_REFERENCED);
164 /* Transfer page changed & referenced bit to guest bits in pgste */
165 pgste_val(pgste) |= bits << 48; /* GR bit & GC bit */
166 /* Copy page access key and fetch protection bit to pgste */
167 pgste_val(pgste) &= ~(PGSTE_ACC_BITS | PGSTE_FP_BIT);
168 pgste_val(pgste) |= (skey & (_PAGE_ACC_BITS | _PAGE_FP_BIT)) << 56;
169#endif
170 return pgste;
171
172}
173
174static inline void pgste_set_key(pte_t *ptep, pgste_t pgste, pte_t entry,
175 struct mm_struct *mm)
176{
177#ifdef CONFIG_PGSTE
178 unsigned long address;
179 unsigned long nkey;
180
181 if (!mm_uses_skeys(mm) || pte_val(entry) & _PAGE_INVALID)
182 return;
183 VM_BUG_ON(!(pte_val(*ptep) & _PAGE_INVALID));
184 address = pte_val(entry) & PAGE_MASK;
185 /*
186 * Set page access key and fetch protection bit from pgste.
187 * The guest C/R information is still in the PGSTE, set real
188 * key C/R to 0.
189 */
190 nkey = (pgste_val(pgste) & (PGSTE_ACC_BITS | PGSTE_FP_BIT)) >> 56;
191 nkey |= (pgste_val(pgste) & (PGSTE_GR_BIT | PGSTE_GC_BIT)) >> 48;
192 page_set_storage_key(address, nkey, 0);
193#endif
194}
195
196static inline pgste_t pgste_set_pte(pte_t *ptep, pgste_t pgste, pte_t entry)
197{
198#ifdef CONFIG_PGSTE
199 if ((pte_val(entry) & _PAGE_PRESENT) &&
200 (pte_val(entry) & _PAGE_WRITE) &&
201 !(pte_val(entry) & _PAGE_INVALID)) {
202 if (!MACHINE_HAS_ESOP) {
203 /*
204 * Without enhanced suppression-on-protection force
205 * the dirty bit on for all writable ptes.
206 */
207 pte_val(entry) |= _PAGE_DIRTY;
208 pte_val(entry) &= ~_PAGE_PROTECT;
209 }
210 if (!(pte_val(entry) & _PAGE_PROTECT))
211 /* This pte allows write access, set user-dirty */
212 pgste_val(pgste) |= PGSTE_UC_BIT;
213 }
214#endif
215 *ptep = entry;
216 return pgste;
217}
218
219static inline pgste_t pgste_pte_notify(struct mm_struct *mm,
220 unsigned long addr,
221 pte_t *ptep, pgste_t pgste)
222{
223#ifdef CONFIG_PGSTE
224 unsigned long bits;
225
226 bits = pgste_val(pgste) & (PGSTE_IN_BIT | PGSTE_VSIE_BIT);
227 if (bits) {
228 pgste_val(pgste) ^= bits;
229 ptep_notify(mm, addr, ptep, bits);
230 }
231#endif
232 return pgste;
233}
234
235static inline pgste_t ptep_xchg_start(struct mm_struct *mm,
236 unsigned long addr, pte_t *ptep)
237{
238 pgste_t pgste = __pgste(0);
239
240 if (mm_has_pgste(mm)) {
241 pgste = pgste_get_lock(ptep);
242 pgste = pgste_pte_notify(mm, addr, ptep, pgste);
243 }
244 return pgste;
245}
246
247static inline pte_t ptep_xchg_commit(struct mm_struct *mm,
248 unsigned long addr, pte_t *ptep,
249 pgste_t pgste, pte_t old, pte_t new)
250{
251 if (mm_has_pgste(mm)) {
252 if (pte_val(old) & _PAGE_INVALID)
253 pgste_set_key(ptep, pgste, new, mm);
254 if (pte_val(new) & _PAGE_INVALID) {
255 pgste = pgste_update_all(old, pgste, mm);
256 if ((pgste_val(pgste) & _PGSTE_GPS_USAGE_MASK) ==
257 _PGSTE_GPS_USAGE_UNUSED)
258 pte_val(old) |= _PAGE_UNUSED;
259 }
260 pgste = pgste_set_pte(ptep, pgste, new);
261 pgste_set_unlock(ptep, pgste);
262 } else {
263 *ptep = new;
264 }
265 return old;
266}
267
268pte_t ptep_xchg_direct(struct mm_struct *mm, unsigned long addr,
269 pte_t *ptep, pte_t new)
270{
271 pgste_t pgste;
272 pte_t old;
273 int nodat;
274
275 preempt_disable();
276 pgste = ptep_xchg_start(mm, addr, ptep);
277 nodat = !!(pgste_val(pgste) & _PGSTE_GPS_NODAT);
278 old = ptep_flush_direct(mm, addr, ptep, nodat);
279 old = ptep_xchg_commit(mm, addr, ptep, pgste, old, new);
280 preempt_enable();
281 return old;
282}
283EXPORT_SYMBOL(ptep_xchg_direct);
284
285pte_t ptep_xchg_lazy(struct mm_struct *mm, unsigned long addr,
286 pte_t *ptep, pte_t new)
287{
288 pgste_t pgste;
289 pte_t old;
290 int nodat;
291
292 preempt_disable();
293 pgste = ptep_xchg_start(mm, addr, ptep);
294 nodat = !!(pgste_val(pgste) & _PGSTE_GPS_NODAT);
295 old = ptep_flush_lazy(mm, addr, ptep, nodat);
296 old = ptep_xchg_commit(mm, addr, ptep, pgste, old, new);
297 preempt_enable();
298 return old;
299}
300EXPORT_SYMBOL(ptep_xchg_lazy);
301
302pte_t ptep_modify_prot_start(struct vm_area_struct *vma, unsigned long addr,
303 pte_t *ptep)
304{
305 pgste_t pgste;
306 pte_t old;
307 int nodat;
308 struct mm_struct *mm = vma->vm_mm;
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
321void ptep_modify_prot_commit(struct vm_area_struct *vma, unsigned long addr,
322 pte_t *ptep, pte_t old_pte, pte_t pte)
323{
324 pgste_t pgste;
325 struct mm_struct *mm = vma->vm_mm;
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
340static inline void pmdp_idte_local(struct mm_struct *mm,
341 unsigned long addr, pmd_t *pmdp)
342{
343 if (MACHINE_HAS_TLB_GUEST)
344 __pmdp_idte(addr, pmdp, IDTE_NODAT | IDTE_GUEST_ASCE,
345 mm->context.asce, IDTE_LOCAL);
346 else
347 __pmdp_idte(addr, pmdp, 0, 0, IDTE_LOCAL);
348 if (mm_has_pgste(mm) && mm->context.allow_gmap_hpage_1m)
349 gmap_pmdp_idte_local(mm, addr);
350}
351
352static inline void pmdp_idte_global(struct mm_struct *mm,
353 unsigned long addr, pmd_t *pmdp)
354{
355 if (MACHINE_HAS_TLB_GUEST) {
356 __pmdp_idte(addr, pmdp, IDTE_NODAT | IDTE_GUEST_ASCE,
357 mm->context.asce, IDTE_GLOBAL);
358 if (mm_has_pgste(mm) && mm->context.allow_gmap_hpage_1m)
359 gmap_pmdp_idte_global(mm, addr);
360 } else if (MACHINE_HAS_IDTE) {
361 __pmdp_idte(addr, pmdp, 0, 0, IDTE_GLOBAL);
362 if (mm_has_pgste(mm) && mm->context.allow_gmap_hpage_1m)
363 gmap_pmdp_idte_global(mm, addr);
364 } else {
365 __pmdp_csp(pmdp);
366 if (mm_has_pgste(mm) && mm->context.allow_gmap_hpage_1m)
367 gmap_pmdp_csp(mm, addr);
368 }
369}
370
371static inline pmd_t pmdp_flush_direct(struct mm_struct *mm,
372 unsigned long addr, pmd_t *pmdp)
373{
374 pmd_t old;
375
376 old = *pmdp;
377 if (pmd_val(old) & _SEGMENT_ENTRY_INVALID)
378 return old;
379 atomic_inc(&mm->context.flush_count);
380 if (MACHINE_HAS_TLB_LC &&
381 cpumask_equal(mm_cpumask(mm), cpumask_of(smp_processor_id())))
382 pmdp_idte_local(mm, addr, pmdp);
383 else
384 pmdp_idte_global(mm, addr, pmdp);
385 atomic_dec(&mm->context.flush_count);
386 return old;
387}
388
389static inline pmd_t pmdp_flush_lazy(struct mm_struct *mm,
390 unsigned long addr, pmd_t *pmdp)
391{
392 pmd_t old;
393
394 old = *pmdp;
395 if (pmd_val(old) & _SEGMENT_ENTRY_INVALID)
396 return old;
397 atomic_inc(&mm->context.flush_count);
398 if (cpumask_equal(&mm->context.cpu_attach_mask,
399 cpumask_of(smp_processor_id()))) {
400 pmd_val(*pmdp) |= _SEGMENT_ENTRY_INVALID;
401 mm->context.flush_mm = 1;
402 if (mm_has_pgste(mm))
403 gmap_pmdp_invalidate(mm, addr);
404 } else {
405 pmdp_idte_global(mm, addr, pmdp);
406 }
407 atomic_dec(&mm->context.flush_count);
408 return old;
409}
410
411#ifdef CONFIG_PGSTE
412static pmd_t *pmd_alloc_map(struct mm_struct *mm, unsigned long addr)
413{
414 pgd_t *pgd;
415 p4d_t *p4d;
416 pud_t *pud;
417 pmd_t *pmd;
418
419 pgd = pgd_offset(mm, addr);
420 p4d = p4d_alloc(mm, pgd, addr);
421 if (!p4d)
422 return NULL;
423 pud = pud_alloc(mm, p4d, addr);
424 if (!pud)
425 return NULL;
426 pmd = pmd_alloc(mm, pud, addr);
427 return pmd;
428}
429#endif
430
431pmd_t pmdp_xchg_direct(struct mm_struct *mm, unsigned long addr,
432 pmd_t *pmdp, pmd_t new)
433{
434 pmd_t old;
435
436 preempt_disable();
437 old = pmdp_flush_direct(mm, addr, pmdp);
438 *pmdp = new;
439 preempt_enable();
440 return old;
441}
442EXPORT_SYMBOL(pmdp_xchg_direct);
443
444pmd_t pmdp_xchg_lazy(struct mm_struct *mm, unsigned long addr,
445 pmd_t *pmdp, pmd_t new)
446{
447 pmd_t old;
448
449 preempt_disable();
450 old = pmdp_flush_lazy(mm, addr, pmdp);
451 *pmdp = new;
452 preempt_enable();
453 return old;
454}
455EXPORT_SYMBOL(pmdp_xchg_lazy);
456
457static inline void pudp_idte_local(struct mm_struct *mm,
458 unsigned long addr, pud_t *pudp)
459{
460 if (MACHINE_HAS_TLB_GUEST)
461 __pudp_idte(addr, pudp, IDTE_NODAT | IDTE_GUEST_ASCE,
462 mm->context.asce, IDTE_LOCAL);
463 else
464 __pudp_idte(addr, pudp, 0, 0, IDTE_LOCAL);
465}
466
467static inline void pudp_idte_global(struct mm_struct *mm,
468 unsigned long addr, pud_t *pudp)
469{
470 if (MACHINE_HAS_TLB_GUEST)
471 __pudp_idte(addr, pudp, IDTE_NODAT | IDTE_GUEST_ASCE,
472 mm->context.asce, IDTE_GLOBAL);
473 else if (MACHINE_HAS_IDTE)
474 __pudp_idte(addr, pudp, 0, 0, IDTE_GLOBAL);
475 else
476 /*
477 * Invalid bit position is the same for pmd and pud, so we can
478 * re-use _pmd_csp() here
479 */
480 __pmdp_csp((pmd_t *) pudp);
481}
482
483static inline pud_t pudp_flush_direct(struct mm_struct *mm,
484 unsigned long addr, pud_t *pudp)
485{
486 pud_t old;
487
488 old = *pudp;
489 if (pud_val(old) & _REGION_ENTRY_INVALID)
490 return old;
491 atomic_inc(&mm->context.flush_count);
492 if (MACHINE_HAS_TLB_LC &&
493 cpumask_equal(mm_cpumask(mm), cpumask_of(smp_processor_id())))
494 pudp_idte_local(mm, addr, pudp);
495 else
496 pudp_idte_global(mm, addr, pudp);
497 atomic_dec(&mm->context.flush_count);
498 return old;
499}
500
501pud_t pudp_xchg_direct(struct mm_struct *mm, unsigned long addr,
502 pud_t *pudp, pud_t new)
503{
504 pud_t old;
505
506 preempt_disable();
507 old = pudp_flush_direct(mm, addr, pudp);
508 *pudp = new;
509 preempt_enable();
510 return old;
511}
512EXPORT_SYMBOL(pudp_xchg_direct);
513
514#ifdef CONFIG_TRANSPARENT_HUGEPAGE
515void pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp,
516 pgtable_t pgtable)
517{
518 struct list_head *lh = (struct list_head *) pgtable;
519
520 assert_spin_locked(pmd_lockptr(mm, pmdp));
521
522 /* FIFO */
523 if (!pmd_huge_pte(mm, pmdp))
524 INIT_LIST_HEAD(lh);
525 else
526 list_add(lh, (struct list_head *) pmd_huge_pte(mm, pmdp));
527 pmd_huge_pte(mm, pmdp) = pgtable;
528}
529
530pgtable_t pgtable_trans_huge_withdraw(struct mm_struct *mm, pmd_t *pmdp)
531{
532 struct list_head *lh;
533 pgtable_t pgtable;
534 pte_t *ptep;
535
536 assert_spin_locked(pmd_lockptr(mm, pmdp));
537
538 /* FIFO */
539 pgtable = pmd_huge_pte(mm, pmdp);
540 lh = (struct list_head *) pgtable;
541 if (list_empty(lh))
542 pmd_huge_pte(mm, pmdp) = NULL;
543 else {
544 pmd_huge_pte(mm, pmdp) = (pgtable_t) lh->next;
545 list_del(lh);
546 }
547 ptep = (pte_t *) pgtable;
548 pte_val(*ptep) = _PAGE_INVALID;
549 ptep++;
550 pte_val(*ptep) = _PAGE_INVALID;
551 return pgtable;
552}
553#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
554
555#ifdef CONFIG_PGSTE
556void ptep_set_pte_at(struct mm_struct *mm, unsigned long addr,
557 pte_t *ptep, pte_t entry)
558{
559 pgste_t pgste;
560
561 /* the mm_has_pgste() check is done in set_pte_at() */
562 preempt_disable();
563 pgste = pgste_get_lock(ptep);
564 pgste_val(pgste) &= ~_PGSTE_GPS_ZERO;
565 pgste_set_key(ptep, pgste, entry, mm);
566 pgste = pgste_set_pte(ptep, pgste, entry);
567 pgste_set_unlock(ptep, pgste);
568 preempt_enable();
569}
570
571void ptep_set_notify(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
572{
573 pgste_t pgste;
574
575 preempt_disable();
576 pgste = pgste_get_lock(ptep);
577 pgste_val(pgste) |= PGSTE_IN_BIT;
578 pgste_set_unlock(ptep, pgste);
579 preempt_enable();
580}
581
582/**
583 * ptep_force_prot - change access rights of a locked pte
584 * @mm: pointer to the process mm_struct
585 * @addr: virtual address in the guest address space
586 * @ptep: pointer to the page table entry
587 * @prot: indicates guest access rights: PROT_NONE, PROT_READ or PROT_WRITE
588 * @bit: pgste bit to set (e.g. for notification)
589 *
590 * Returns 0 if the access rights were changed and -EAGAIN if the current
591 * and requested access rights are incompatible.
592 */
593int ptep_force_prot(struct mm_struct *mm, unsigned long addr,
594 pte_t *ptep, int prot, unsigned long bit)
595{
596 pte_t entry;
597 pgste_t pgste;
598 int pte_i, pte_p, nodat;
599
600 pgste = pgste_get_lock(ptep);
601 entry = *ptep;
602 /* Check pte entry after all locks have been acquired */
603 pte_i = pte_val(entry) & _PAGE_INVALID;
604 pte_p = pte_val(entry) & _PAGE_PROTECT;
605 if ((pte_i && (prot != PROT_NONE)) ||
606 (pte_p && (prot & PROT_WRITE))) {
607 pgste_set_unlock(ptep, pgste);
608 return -EAGAIN;
609 }
610 /* Change access rights and set pgste bit */
611 nodat = !!(pgste_val(pgste) & _PGSTE_GPS_NODAT);
612 if (prot == PROT_NONE && !pte_i) {
613 ptep_flush_direct(mm, addr, ptep, nodat);
614 pgste = pgste_update_all(entry, pgste, mm);
615 pte_val(entry) |= _PAGE_INVALID;
616 }
617 if (prot == PROT_READ && !pte_p) {
618 ptep_flush_direct(mm, addr, ptep, nodat);
619 pte_val(entry) &= ~_PAGE_INVALID;
620 pte_val(entry) |= _PAGE_PROTECT;
621 }
622 pgste_val(pgste) |= bit;
623 pgste = pgste_set_pte(ptep, pgste, entry);
624 pgste_set_unlock(ptep, pgste);
625 return 0;
626}
627
628int ptep_shadow_pte(struct mm_struct *mm, unsigned long saddr,
629 pte_t *sptep, pte_t *tptep, pte_t pte)
630{
631 pgste_t spgste, tpgste;
632 pte_t spte, tpte;
633 int rc = -EAGAIN;
634
635 if (!(pte_val(*tptep) & _PAGE_INVALID))
636 return 0; /* already shadowed */
637 spgste = pgste_get_lock(sptep);
638 spte = *sptep;
639 if (!(pte_val(spte) & _PAGE_INVALID) &&
640 !((pte_val(spte) & _PAGE_PROTECT) &&
641 !(pte_val(pte) & _PAGE_PROTECT))) {
642 pgste_val(spgste) |= PGSTE_VSIE_BIT;
643 tpgste = pgste_get_lock(tptep);
644 pte_val(tpte) = (pte_val(spte) & PAGE_MASK) |
645 (pte_val(pte) & _PAGE_PROTECT);
646 /* don't touch the storage key - it belongs to parent pgste */
647 tpgste = pgste_set_pte(tptep, tpgste, tpte);
648 pgste_set_unlock(tptep, tpgste);
649 rc = 1;
650 }
651 pgste_set_unlock(sptep, spgste);
652 return rc;
653}
654
655void ptep_unshadow_pte(struct mm_struct *mm, unsigned long saddr, pte_t *ptep)
656{
657 pgste_t pgste;
658 int nodat;
659
660 pgste = pgste_get_lock(ptep);
661 /* notifier is called by the caller */
662 nodat = !!(pgste_val(pgste) & _PGSTE_GPS_NODAT);
663 ptep_flush_direct(mm, saddr, ptep, nodat);
664 /* don't touch the storage key - it belongs to parent pgste */
665 pgste = pgste_set_pte(ptep, pgste, __pte(_PAGE_INVALID));
666 pgste_set_unlock(ptep, pgste);
667}
668
669static void ptep_zap_swap_entry(struct mm_struct *mm, swp_entry_t entry)
670{
671 if (!non_swap_entry(entry))
672 dec_mm_counter(mm, MM_SWAPENTS);
673 else if (is_migration_entry(entry)) {
674 struct page *page = migration_entry_to_page(entry);
675
676 dec_mm_counter(mm, mm_counter(page));
677 }
678 free_swap_and_cache(entry);
679}
680
681void ptep_zap_unused(struct mm_struct *mm, unsigned long addr,
682 pte_t *ptep, int reset)
683{
684 unsigned long pgstev;
685 pgste_t pgste;
686 pte_t pte;
687
688 /* Zap unused and logically-zero pages */
689 preempt_disable();
690 pgste = pgste_get_lock(ptep);
691 pgstev = pgste_val(pgste);
692 pte = *ptep;
693 if (!reset && pte_swap(pte) &&
694 ((pgstev & _PGSTE_GPS_USAGE_MASK) == _PGSTE_GPS_USAGE_UNUSED ||
695 (pgstev & _PGSTE_GPS_ZERO))) {
696 ptep_zap_swap_entry(mm, pte_to_swp_entry(pte));
697 pte_clear(mm, addr, ptep);
698 }
699 if (reset)
700 pgste_val(pgste) &= ~_PGSTE_GPS_USAGE_MASK;
701 pgste_set_unlock(ptep, pgste);
702 preempt_enable();
703}
704
705void ptep_zap_key(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
706{
707 unsigned long ptev;
708 pgste_t pgste;
709
710 /* Clear storage key ACC and F, but set R/C */
711 preempt_disable();
712 pgste = pgste_get_lock(ptep);
713 pgste_val(pgste) &= ~(PGSTE_ACC_BITS | PGSTE_FP_BIT);
714 pgste_val(pgste) |= PGSTE_GR_BIT | PGSTE_GC_BIT;
715 ptev = pte_val(*ptep);
716 if (!(ptev & _PAGE_INVALID) && (ptev & _PAGE_WRITE))
717 page_set_storage_key(ptev & PAGE_MASK, PAGE_DEFAULT_KEY, 1);
718 pgste_set_unlock(ptep, pgste);
719 preempt_enable();
720}
721
722/*
723 * Test and reset if a guest page is dirty
724 */
725bool ptep_test_and_clear_uc(struct mm_struct *mm, unsigned long addr,
726 pte_t *ptep)
727{
728 pgste_t pgste;
729 pte_t pte;
730 bool dirty;
731 int nodat;
732
733 pgste = pgste_get_lock(ptep);
734 dirty = !!(pgste_val(pgste) & PGSTE_UC_BIT);
735 pgste_val(pgste) &= ~PGSTE_UC_BIT;
736 pte = *ptep;
737 if (dirty && (pte_val(pte) & _PAGE_PRESENT)) {
738 pgste = pgste_pte_notify(mm, addr, ptep, pgste);
739 nodat = !!(pgste_val(pgste) & _PGSTE_GPS_NODAT);
740 ptep_ipte_global(mm, addr, ptep, nodat);
741 if (MACHINE_HAS_ESOP || !(pte_val(pte) & _PAGE_WRITE))
742 pte_val(pte) |= _PAGE_PROTECT;
743 else
744 pte_val(pte) |= _PAGE_INVALID;
745 *ptep = pte;
746 }
747 pgste_set_unlock(ptep, pgste);
748 return dirty;
749}
750EXPORT_SYMBOL_GPL(ptep_test_and_clear_uc);
751
752int set_guest_storage_key(struct mm_struct *mm, unsigned long addr,
753 unsigned char key, bool nq)
754{
755 unsigned long keyul, paddr;
756 spinlock_t *ptl;
757 pgste_t old, new;
758 pmd_t *pmdp;
759 pte_t *ptep;
760
761 pmdp = pmd_alloc_map(mm, addr);
762 if (unlikely(!pmdp))
763 return -EFAULT;
764
765 ptl = pmd_lock(mm, pmdp);
766 if (!pmd_present(*pmdp)) {
767 spin_unlock(ptl);
768 return -EFAULT;
769 }
770
771 if (pmd_large(*pmdp)) {
772 paddr = pmd_val(*pmdp) & HPAGE_MASK;
773 paddr |= addr & ~HPAGE_MASK;
774 /*
775 * Huge pmds need quiescing operations, they are
776 * always mapped.
777 */
778 page_set_storage_key(paddr, key, 1);
779 spin_unlock(ptl);
780 return 0;
781 }
782 spin_unlock(ptl);
783
784 ptep = pte_alloc_map_lock(mm, pmdp, addr, &ptl);
785 if (unlikely(!ptep))
786 return -EFAULT;
787
788 new = old = pgste_get_lock(ptep);
789 pgste_val(new) &= ~(PGSTE_GR_BIT | PGSTE_GC_BIT |
790 PGSTE_ACC_BITS | PGSTE_FP_BIT);
791 keyul = (unsigned long) key;
792 pgste_val(new) |= (keyul & (_PAGE_CHANGED | _PAGE_REFERENCED)) << 48;
793 pgste_val(new) |= (keyul & (_PAGE_ACC_BITS | _PAGE_FP_BIT)) << 56;
794 if (!(pte_val(*ptep) & _PAGE_INVALID)) {
795 unsigned long bits, skey;
796
797 paddr = pte_val(*ptep) & PAGE_MASK;
798 skey = (unsigned long) page_get_storage_key(paddr);
799 bits = skey & (_PAGE_CHANGED | _PAGE_REFERENCED);
800 skey = key & (_PAGE_ACC_BITS | _PAGE_FP_BIT);
801 /* Set storage key ACC and FP */
802 page_set_storage_key(paddr, skey, !nq);
803 /* Merge host changed & referenced into pgste */
804 pgste_val(new) |= bits << 52;
805 }
806 /* changing the guest storage key is considered a change of the page */
807 if ((pgste_val(new) ^ pgste_val(old)) &
808 (PGSTE_ACC_BITS | PGSTE_FP_BIT | PGSTE_GR_BIT | PGSTE_GC_BIT))
809 pgste_val(new) |= PGSTE_UC_BIT;
810
811 pgste_set_unlock(ptep, new);
812 pte_unmap_unlock(ptep, ptl);
813 return 0;
814}
815EXPORT_SYMBOL(set_guest_storage_key);
816
817/**
818 * Conditionally set a guest storage key (handling csske).
819 * oldkey will be updated when either mr or mc is set and a pointer is given.
820 *
821 * Returns 0 if a guests storage key update wasn't necessary, 1 if the guest
822 * storage key was updated and -EFAULT on access errors.
823 */
824int cond_set_guest_storage_key(struct mm_struct *mm, unsigned long addr,
825 unsigned char key, unsigned char *oldkey,
826 bool nq, bool mr, bool mc)
827{
828 unsigned char tmp, mask = _PAGE_ACC_BITS | _PAGE_FP_BIT;
829 int rc;
830
831 /* we can drop the pgste lock between getting and setting the key */
832 if (mr | mc) {
833 rc = get_guest_storage_key(current->mm, addr, &tmp);
834 if (rc)
835 return rc;
836 if (oldkey)
837 *oldkey = tmp;
838 if (!mr)
839 mask |= _PAGE_REFERENCED;
840 if (!mc)
841 mask |= _PAGE_CHANGED;
842 if (!((tmp ^ key) & mask))
843 return 0;
844 }
845 rc = set_guest_storage_key(current->mm, addr, key, nq);
846 return rc < 0 ? rc : 1;
847}
848EXPORT_SYMBOL(cond_set_guest_storage_key);
849
850/**
851 * Reset a guest reference bit (rrbe), returning the reference and changed bit.
852 *
853 * Returns < 0 in case of error, otherwise the cc to be reported to the guest.
854 */
855int reset_guest_reference_bit(struct mm_struct *mm, unsigned long addr)
856{
857 spinlock_t *ptl;
858 unsigned long paddr;
859 pgste_t old, new;
860 pmd_t *pmdp;
861 pte_t *ptep;
862 int cc = 0;
863
864 pmdp = pmd_alloc_map(mm, addr);
865 if (unlikely(!pmdp))
866 return -EFAULT;
867
868 ptl = pmd_lock(mm, pmdp);
869 if (!pmd_present(*pmdp)) {
870 spin_unlock(ptl);
871 return -EFAULT;
872 }
873
874 if (pmd_large(*pmdp)) {
875 paddr = pmd_val(*pmdp) & HPAGE_MASK;
876 paddr |= addr & ~HPAGE_MASK;
877 cc = page_reset_referenced(paddr);
878 spin_unlock(ptl);
879 return cc;
880 }
881 spin_unlock(ptl);
882
883 ptep = pte_alloc_map_lock(mm, pmdp, addr, &ptl);
884 if (unlikely(!ptep))
885 return -EFAULT;
886
887 new = old = pgste_get_lock(ptep);
888 /* Reset guest reference bit only */
889 pgste_val(new) &= ~PGSTE_GR_BIT;
890
891 if (!(pte_val(*ptep) & _PAGE_INVALID)) {
892 paddr = pte_val(*ptep) & PAGE_MASK;
893 cc = page_reset_referenced(paddr);
894 /* Merge real referenced bit into host-set */
895 pgste_val(new) |= ((unsigned long) cc << 53) & PGSTE_HR_BIT;
896 }
897 /* Reflect guest's logical view, not physical */
898 cc |= (pgste_val(old) & (PGSTE_GR_BIT | PGSTE_GC_BIT)) >> 49;
899 /* Changing the guest storage key is considered a change of the page */
900 if ((pgste_val(new) ^ pgste_val(old)) & PGSTE_GR_BIT)
901 pgste_val(new) |= PGSTE_UC_BIT;
902
903 pgste_set_unlock(ptep, new);
904 pte_unmap_unlock(ptep, ptl);
905 return cc;
906}
907EXPORT_SYMBOL(reset_guest_reference_bit);
908
909int get_guest_storage_key(struct mm_struct *mm, unsigned long addr,
910 unsigned char *key)
911{
912 unsigned long paddr;
913 spinlock_t *ptl;
914 pgste_t pgste;
915 pmd_t *pmdp;
916 pte_t *ptep;
917
918 pmdp = pmd_alloc_map(mm, addr);
919 if (unlikely(!pmdp))
920 return -EFAULT;
921
922 ptl = pmd_lock(mm, pmdp);
923 if (!pmd_present(*pmdp)) {
924 /* Not yet mapped memory has a zero key */
925 spin_unlock(ptl);
926 *key = 0;
927 return 0;
928 }
929
930 if (pmd_large(*pmdp)) {
931 paddr = pmd_val(*pmdp) & HPAGE_MASK;
932 paddr |= addr & ~HPAGE_MASK;
933 *key = page_get_storage_key(paddr);
934 spin_unlock(ptl);
935 return 0;
936 }
937 spin_unlock(ptl);
938
939 ptep = pte_alloc_map_lock(mm, pmdp, addr, &ptl);
940 if (unlikely(!ptep))
941 return -EFAULT;
942
943 pgste = pgste_get_lock(ptep);
944 *key = (pgste_val(pgste) & (PGSTE_ACC_BITS | PGSTE_FP_BIT)) >> 56;
945 paddr = pte_val(*ptep) & PAGE_MASK;
946 if (!(pte_val(*ptep) & _PAGE_INVALID))
947 *key = page_get_storage_key(paddr);
948 /* Reflect guest's logical view, not physical */
949 *key |= (pgste_val(pgste) & (PGSTE_GR_BIT | PGSTE_GC_BIT)) >> 48;
950 pgste_set_unlock(ptep, pgste);
951 pte_unmap_unlock(ptep, ptl);
952 return 0;
953}
954EXPORT_SYMBOL(get_guest_storage_key);
955
956/**
957 * pgste_perform_essa - perform ESSA actions on the PGSTE.
958 * @mm: the memory context. It must have PGSTEs, no check is performed here!
959 * @hva: the host virtual address of the page whose PGSTE is to be processed
960 * @orc: the specific action to perform, see the ESSA_SET_* macros.
961 * @oldpte: the PTE will be saved there if the pointer is not NULL.
962 * @oldpgste: the old PGSTE will be saved there if the pointer is not NULL.
963 *
964 * Return: 1 if the page is to be added to the CBRL, otherwise 0,
965 * or < 0 in case of error. -EINVAL is returned for invalid values
966 * of orc, -EFAULT for invalid addresses.
967 */
968int pgste_perform_essa(struct mm_struct *mm, unsigned long hva, int orc,
969 unsigned long *oldpte, unsigned long *oldpgste)
970{
971 unsigned long pgstev;
972 spinlock_t *ptl;
973 pgste_t pgste;
974 pte_t *ptep;
975 int res = 0;
976
977 WARN_ON_ONCE(orc > ESSA_MAX);
978 if (unlikely(orc > ESSA_MAX))
979 return -EINVAL;
980 ptep = get_locked_pte(mm, hva, &ptl);
981 if (unlikely(!ptep))
982 return -EFAULT;
983 pgste = pgste_get_lock(ptep);
984 pgstev = pgste_val(pgste);
985 if (oldpte)
986 *oldpte = pte_val(*ptep);
987 if (oldpgste)
988 *oldpgste = pgstev;
989
990 switch (orc) {
991 case ESSA_GET_STATE:
992 break;
993 case ESSA_SET_STABLE:
994 pgstev &= ~(_PGSTE_GPS_USAGE_MASK | _PGSTE_GPS_NODAT);
995 pgstev |= _PGSTE_GPS_USAGE_STABLE;
996 break;
997 case ESSA_SET_UNUSED:
998 pgstev &= ~_PGSTE_GPS_USAGE_MASK;
999 pgstev |= _PGSTE_GPS_USAGE_UNUSED;
1000 if (pte_val(*ptep) & _PAGE_INVALID)
1001 res = 1;
1002 break;
1003 case ESSA_SET_VOLATILE:
1004 pgstev &= ~_PGSTE_GPS_USAGE_MASK;
1005 pgstev |= _PGSTE_GPS_USAGE_VOLATILE;
1006 if (pte_val(*ptep) & _PAGE_INVALID)
1007 res = 1;
1008 break;
1009 case ESSA_SET_POT_VOLATILE:
1010 pgstev &= ~_PGSTE_GPS_USAGE_MASK;
1011 if (!(pte_val(*ptep) & _PAGE_INVALID)) {
1012 pgstev |= _PGSTE_GPS_USAGE_POT_VOLATILE;
1013 break;
1014 }
1015 if (pgstev & _PGSTE_GPS_ZERO) {
1016 pgstev |= _PGSTE_GPS_USAGE_VOLATILE;
1017 break;
1018 }
1019 if (!(pgstev & PGSTE_GC_BIT)) {
1020 pgstev |= _PGSTE_GPS_USAGE_VOLATILE;
1021 res = 1;
1022 break;
1023 }
1024 break;
1025 case ESSA_SET_STABLE_RESIDENT:
1026 pgstev &= ~_PGSTE_GPS_USAGE_MASK;
1027 pgstev |= _PGSTE_GPS_USAGE_STABLE;
1028 /*
1029 * Since the resident state can go away any time after this
1030 * call, we will not make this page resident. We can revisit
1031 * this decision if a guest will ever start using this.
1032 */
1033 break;
1034 case ESSA_SET_STABLE_IF_RESIDENT:
1035 if (!(pte_val(*ptep) & _PAGE_INVALID)) {
1036 pgstev &= ~_PGSTE_GPS_USAGE_MASK;
1037 pgstev |= _PGSTE_GPS_USAGE_STABLE;
1038 }
1039 break;
1040 case ESSA_SET_STABLE_NODAT:
1041 pgstev &= ~_PGSTE_GPS_USAGE_MASK;
1042 pgstev |= _PGSTE_GPS_USAGE_STABLE | _PGSTE_GPS_NODAT;
1043 break;
1044 default:
1045 /* we should never get here! */
1046 break;
1047 }
1048 /* If we are discarding a page, set it to logical zero */
1049 if (res)
1050 pgstev |= _PGSTE_GPS_ZERO;
1051
1052 pgste_val(pgste) = pgstev;
1053 pgste_set_unlock(ptep, pgste);
1054 pte_unmap_unlock(ptep, ptl);
1055 return res;
1056}
1057EXPORT_SYMBOL(pgste_perform_essa);
1058
1059/**
1060 * set_pgste_bits - set specific PGSTE bits.
1061 * @mm: the memory context. It must have PGSTEs, no check is performed here!
1062 * @hva: the host virtual address of the page whose PGSTE is to be processed
1063 * @bits: a bitmask representing the bits that will be touched
1064 * @value: the values of the bits to be written. Only the bits in the mask
1065 * will be written.
1066 *
1067 * Return: 0 on success, < 0 in case of error.
1068 */
1069int set_pgste_bits(struct mm_struct *mm, unsigned long hva,
1070 unsigned long bits, unsigned long value)
1071{
1072 spinlock_t *ptl;
1073 pgste_t new;
1074 pte_t *ptep;
1075
1076 ptep = get_locked_pte(mm, hva, &ptl);
1077 if (unlikely(!ptep))
1078 return -EFAULT;
1079 new = pgste_get_lock(ptep);
1080
1081 pgste_val(new) &= ~bits;
1082 pgste_val(new) |= value & bits;
1083
1084 pgste_set_unlock(ptep, new);
1085 pte_unmap_unlock(ptep, ptl);
1086 return 0;
1087}
1088EXPORT_SYMBOL(set_pgste_bits);
1089
1090/**
1091 * get_pgste - get the current PGSTE for the given address.
1092 * @mm: the memory context. It must have PGSTEs, no check is performed here!
1093 * @hva: the host virtual address of the page whose PGSTE is to be processed
1094 * @pgstep: will be written with the current PGSTE for the given address.
1095 *
1096 * Return: 0 on success, < 0 in case of error.
1097 */
1098int get_pgste(struct mm_struct *mm, unsigned long hva, unsigned long *pgstep)
1099{
1100 spinlock_t *ptl;
1101 pte_t *ptep;
1102
1103 ptep = get_locked_pte(mm, hva, &ptl);
1104 if (unlikely(!ptep))
1105 return -EFAULT;
1106 *pgstep = pgste_val(pgste_get(ptep));
1107 pte_unmap_unlock(ptep, ptl);
1108 return 0;
1109}
1110EXPORT_SYMBOL(get_pgste);
1111#endif