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 | |
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 | |
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 | |
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 | |
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 | |
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(v: &mm->context.flush_count); |
97 | if (MACHINE_HAS_TLB_LC && |
98 | cpumask_equal(src1p: 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(v: &mm->context.flush_count); |
103 | return old; |
104 | } |
105 | |
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(v: &mm->context.flush_count); |
116 | if (cpumask_equal(src1p: &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(v: &mm->context.flush_count); |
123 | return old; |
124 | } |
125 | |
126 | static inline pgste_t pgste_get_lock(pte_t *ptep) |
127 | { |
128 | unsigned long value = 0; |
129 | #ifdef CONFIG_PGSTE |
130 | unsigned long *ptr = (unsigned long *)(ptep + PTRS_PER_PTE); |
131 | |
132 | do { |
133 | value = __atomic64_or_barrier(PGSTE_PCL_BIT, ptr); |
134 | } while (value & PGSTE_PCL_BIT); |
135 | value |= PGSTE_PCL_BIT; |
136 | #endif |
137 | return __pgste(value); |
138 | } |
139 | |
140 | static inline void pgste_set_unlock(pte_t *ptep, pgste_t pgste) |
141 | { |
142 | #ifdef CONFIG_PGSTE |
143 | barrier(); |
144 | WRITE_ONCE(*(unsigned long *)(ptep + PTRS_PER_PTE), pgste_val(pgste) & ~PGSTE_PCL_BIT); |
145 | #endif |
146 | } |
147 | |
148 | static inline pgste_t pgste_get(pte_t *ptep) |
149 | { |
150 | unsigned long pgste = 0; |
151 | #ifdef CONFIG_PGSTE |
152 | pgste = *(unsigned long *)(ptep + PTRS_PER_PTE); |
153 | #endif |
154 | return __pgste(pgste); |
155 | } |
156 | |
157 | static inline void pgste_set(pte_t *ptep, pgste_t pgste) |
158 | { |
159 | #ifdef CONFIG_PGSTE |
160 | *(pgste_t *)(ptep + PTRS_PER_PTE) = pgste; |
161 | #endif |
162 | } |
163 | |
164 | static inline pgste_t pgste_update_all(pte_t pte, pgste_t pgste, |
165 | struct mm_struct *mm) |
166 | { |
167 | #ifdef CONFIG_PGSTE |
168 | unsigned long address, bits, skey; |
169 | |
170 | if (!mm_uses_skeys(mm) || pte_val(pte) & _PAGE_INVALID) |
171 | return pgste; |
172 | address = pte_val(pte) & PAGE_MASK; |
173 | skey = (unsigned long) page_get_storage_key(address); |
174 | bits = skey & (_PAGE_CHANGED | _PAGE_REFERENCED); |
175 | /* Transfer page changed & referenced bit to guest bits in pgste */ |
176 | pgste_val(pgste) |= bits << 48; /* GR bit & GC bit */ |
177 | /* Copy page access key and fetch protection bit to pgste */ |
178 | pgste_val(pgste) &= ~(PGSTE_ACC_BITS | PGSTE_FP_BIT); |
179 | pgste_val(pgste) |= (skey & (_PAGE_ACC_BITS | _PAGE_FP_BIT)) << 56; |
180 | #endif |
181 | return pgste; |
182 | |
183 | } |
184 | |
185 | static inline void pgste_set_key(pte_t *ptep, pgste_t pgste, pte_t entry, |
186 | struct mm_struct *mm) |
187 | { |
188 | #ifdef CONFIG_PGSTE |
189 | unsigned long address; |
190 | unsigned long nkey; |
191 | |
192 | if (!mm_uses_skeys(mm) || pte_val(entry) & _PAGE_INVALID) |
193 | return; |
194 | VM_BUG_ON(!(pte_val(*ptep) & _PAGE_INVALID)); |
195 | address = pte_val(entry) & PAGE_MASK; |
196 | /* |
197 | * Set page access key and fetch protection bit from pgste. |
198 | * The guest C/R information is still in the PGSTE, set real |
199 | * key C/R to 0. |
200 | */ |
201 | nkey = (pgste_val(pgste) & (PGSTE_ACC_BITS | PGSTE_FP_BIT)) >> 56; |
202 | nkey |= (pgste_val(pgste) & (PGSTE_GR_BIT | PGSTE_GC_BIT)) >> 48; |
203 | page_set_storage_key(address, nkey, 0); |
204 | #endif |
205 | } |
206 | |
207 | static inline pgste_t pgste_set_pte(pte_t *ptep, pgste_t pgste, pte_t entry) |
208 | { |
209 | #ifdef CONFIG_PGSTE |
210 | if ((pte_val(entry) & _PAGE_PRESENT) && |
211 | (pte_val(entry) & _PAGE_WRITE) && |
212 | !(pte_val(entry) & _PAGE_INVALID)) { |
213 | if (!MACHINE_HAS_ESOP) { |
214 | /* |
215 | * Without enhanced suppression-on-protection force |
216 | * the dirty bit on for all writable ptes. |
217 | */ |
218 | entry = set_pte_bit(entry, __pgprot(_PAGE_DIRTY)); |
219 | entry = clear_pte_bit(entry, __pgprot(_PAGE_PROTECT)); |
220 | } |
221 | if (!(pte_val(entry) & _PAGE_PROTECT)) |
222 | /* This pte allows write access, set user-dirty */ |
223 | pgste_val(pgste) |= PGSTE_UC_BIT; |
224 | } |
225 | #endif |
226 | set_pte(ptep, pte: entry); |
227 | return pgste; |
228 | } |
229 | |
230 | static inline pgste_t pgste_pte_notify(struct mm_struct *mm, |
231 | unsigned long addr, |
232 | pte_t *ptep, pgste_t pgste) |
233 | { |
234 | #ifdef CONFIG_PGSTE |
235 | unsigned long bits; |
236 | |
237 | bits = pgste_val(pgste) & (PGSTE_IN_BIT | PGSTE_VSIE_BIT); |
238 | if (bits) { |
239 | pgste_val(pgste) ^= bits; |
240 | ptep_notify(mm, addr, ptep, bits); |
241 | } |
242 | #endif |
243 | return pgste; |
244 | } |
245 | |
246 | static inline pgste_t ptep_xchg_start(struct mm_struct *mm, |
247 | unsigned long addr, pte_t *ptep) |
248 | { |
249 | pgste_t pgste = __pgste(0); |
250 | |
251 | if (mm_has_pgste(mm)) { |
252 | pgste = pgste_get_lock(ptep); |
253 | pgste = pgste_pte_notify(mm, addr, ptep, pgste); |
254 | } |
255 | return pgste; |
256 | } |
257 | |
258 | static inline pte_t ptep_xchg_commit(struct mm_struct *mm, |
259 | unsigned long addr, pte_t *ptep, |
260 | pgste_t pgste, pte_t old, pte_t new) |
261 | { |
262 | if (mm_has_pgste(mm)) { |
263 | if (pte_val(old) & _PAGE_INVALID) |
264 | pgste_set_key(ptep, pgste, new, mm); |
265 | if (pte_val(new) & _PAGE_INVALID) { |
266 | pgste = pgste_update_all(old, pgste, mm); |
267 | if ((pgste_val(pgste) & _PGSTE_GPS_USAGE_MASK) == |
268 | _PGSTE_GPS_USAGE_UNUSED) |
269 | old = set_pte_bit(old, __pgprot(_PAGE_UNUSED)); |
270 | } |
271 | pgste = pgste_set_pte(ptep, pgste, new); |
272 | pgste_set_unlock(ptep, pgste); |
273 | } else { |
274 | set_pte(ptep, pte: new); |
275 | } |
276 | return old; |
277 | } |
278 | |
279 | pte_t ptep_xchg_direct(struct mm_struct *mm, unsigned long addr, |
280 | pte_t *ptep, pte_t new) |
281 | { |
282 | pgste_t pgste; |
283 | pte_t old; |
284 | int nodat; |
285 | |
286 | preempt_disable(); |
287 | pgste = ptep_xchg_start(mm, addr, ptep); |
288 | nodat = !!(pgste_val(pgste) & _PGSTE_GPS_NODAT); |
289 | old = ptep_flush_direct(mm, addr, ptep, nodat); |
290 | old = ptep_xchg_commit(mm, addr, ptep, pgste, old, new); |
291 | preempt_enable(); |
292 | return old; |
293 | } |
294 | EXPORT_SYMBOL(ptep_xchg_direct); |
295 | |
296 | /* |
297 | * Caller must check that new PTE only differs in _PAGE_PROTECT HW bit, so that |
298 | * RDP can be used instead of IPTE. See also comments at pte_allow_rdp(). |
299 | */ |
300 | void ptep_reset_dat_prot(struct mm_struct *mm, unsigned long addr, pte_t *ptep, |
301 | pte_t new) |
302 | { |
303 | preempt_disable(); |
304 | atomic_inc(v: &mm->context.flush_count); |
305 | if (cpumask_equal(src1p: mm_cpumask(mm), cpumask_of(smp_processor_id()))) |
306 | __ptep_rdp(addr, ptep, 0, 0, 1); |
307 | else |
308 | __ptep_rdp(addr, ptep, 0, 0, 0); |
309 | /* |
310 | * PTE is not invalidated by RDP, only _PAGE_PROTECT is cleared. That |
311 | * means it is still valid and active, and must not be changed according |
312 | * to the architecture. But writing a new value that only differs in SW |
313 | * bits is allowed. |
314 | */ |
315 | set_pte(ptep, pte: new); |
316 | atomic_dec(v: &mm->context.flush_count); |
317 | preempt_enable(); |
318 | } |
319 | EXPORT_SYMBOL(ptep_reset_dat_prot); |
320 | |
321 | pte_t ptep_xchg_lazy(struct mm_struct *mm, unsigned long addr, |
322 | pte_t *ptep, pte_t new) |
323 | { |
324 | pgste_t pgste; |
325 | pte_t old; |
326 | int nodat; |
327 | |
328 | preempt_disable(); |
329 | pgste = ptep_xchg_start(mm, addr, ptep); |
330 | nodat = !!(pgste_val(pgste) & _PGSTE_GPS_NODAT); |
331 | old = ptep_flush_lazy(mm, addr, ptep, nodat); |
332 | old = ptep_xchg_commit(mm, addr, ptep, pgste, old, new); |
333 | preempt_enable(); |
334 | return old; |
335 | } |
336 | EXPORT_SYMBOL(ptep_xchg_lazy); |
337 | |
338 | pte_t ptep_modify_prot_start(struct vm_area_struct *vma, unsigned long addr, |
339 | pte_t *ptep) |
340 | { |
341 | pgste_t pgste; |
342 | pte_t old; |
343 | int nodat; |
344 | struct mm_struct *mm = vma->vm_mm; |
345 | |
346 | preempt_disable(); |
347 | pgste = ptep_xchg_start(mm, addr, ptep); |
348 | nodat = !!(pgste_val(pgste) & _PGSTE_GPS_NODAT); |
349 | old = ptep_flush_lazy(mm, addr, ptep, nodat); |
350 | if (mm_has_pgste(mm)) { |
351 | pgste = pgste_update_all(old, pgste, mm); |
352 | pgste_set(ptep, pgste); |
353 | } |
354 | return old; |
355 | } |
356 | |
357 | void ptep_modify_prot_commit(struct vm_area_struct *vma, unsigned long addr, |
358 | pte_t *ptep, pte_t old_pte, pte_t pte) |
359 | { |
360 | pgste_t pgste; |
361 | struct mm_struct *mm = vma->vm_mm; |
362 | |
363 | if (!MACHINE_HAS_NX) |
364 | pte = clear_pte_bit(pte, __pgprot(_PAGE_NOEXEC)); |
365 | if (mm_has_pgste(mm)) { |
366 | pgste = pgste_get(ptep); |
367 | pgste_set_key(ptep, pgste, pte, mm); |
368 | pgste = pgste_set_pte(ptep, pgste, pte); |
369 | pgste_set_unlock(ptep, pgste); |
370 | } else { |
371 | set_pte(ptep, pte); |
372 | } |
373 | preempt_enable(); |
374 | } |
375 | |
376 | static inline void pmdp_idte_local(struct mm_struct *mm, |
377 | unsigned long addr, pmd_t *pmdp) |
378 | { |
379 | if (MACHINE_HAS_TLB_GUEST) |
380 | __pmdp_idte(addr, pmdp, IDTE_NODAT | IDTE_GUEST_ASCE, |
381 | mm->context.asce, IDTE_LOCAL); |
382 | else |
383 | __pmdp_idte(addr, pmdp, 0, 0, IDTE_LOCAL); |
384 | if (mm_has_pgste(mm) && mm->context.allow_gmap_hpage_1m) |
385 | gmap_pmdp_idte_local(mm, addr); |
386 | } |
387 | |
388 | static inline void pmdp_idte_global(struct mm_struct *mm, |
389 | unsigned long addr, pmd_t *pmdp) |
390 | { |
391 | if (MACHINE_HAS_TLB_GUEST) { |
392 | __pmdp_idte(addr, pmdp, IDTE_NODAT | IDTE_GUEST_ASCE, |
393 | mm->context.asce, IDTE_GLOBAL); |
394 | if (mm_has_pgste(mm) && mm->context.allow_gmap_hpage_1m) |
395 | gmap_pmdp_idte_global(mm, addr); |
396 | } else if (MACHINE_HAS_IDTE) { |
397 | __pmdp_idte(addr, pmdp, 0, 0, IDTE_GLOBAL); |
398 | if (mm_has_pgste(mm) && mm->context.allow_gmap_hpage_1m) |
399 | gmap_pmdp_idte_global(mm, addr); |
400 | } else { |
401 | __pmdp_csp(pmdp); |
402 | if (mm_has_pgste(mm) && mm->context.allow_gmap_hpage_1m) |
403 | gmap_pmdp_csp(mm, addr); |
404 | } |
405 | } |
406 | |
407 | static inline pmd_t pmdp_flush_direct(struct mm_struct *mm, |
408 | unsigned long addr, pmd_t *pmdp) |
409 | { |
410 | pmd_t old; |
411 | |
412 | old = *pmdp; |
413 | if (pmd_val(old) & _SEGMENT_ENTRY_INVALID) |
414 | return old; |
415 | atomic_inc(v: &mm->context.flush_count); |
416 | if (MACHINE_HAS_TLB_LC && |
417 | cpumask_equal(mm_cpumask(mm), cpumask_of(smp_processor_id()))) |
418 | pmdp_idte_local(mm, addr, pmdp); |
419 | else |
420 | pmdp_idte_global(mm, addr, pmdp); |
421 | atomic_dec(v: &mm->context.flush_count); |
422 | return old; |
423 | } |
424 | |
425 | static inline pmd_t pmdp_flush_lazy(struct mm_struct *mm, |
426 | unsigned long addr, pmd_t *pmdp) |
427 | { |
428 | pmd_t old; |
429 | |
430 | old = *pmdp; |
431 | if (pmd_val(old) & _SEGMENT_ENTRY_INVALID) |
432 | return old; |
433 | atomic_inc(v: &mm->context.flush_count); |
434 | if (cpumask_equal(src1p: &mm->context.cpu_attach_mask, |
435 | cpumask_of(smp_processor_id()))) { |
436 | set_pmd(pmdp, set_pmd_bit(*pmdp, __pgprot(_SEGMENT_ENTRY_INVALID))); |
437 | mm->context.flush_mm = 1; |
438 | if (mm_has_pgste(mm)) |
439 | gmap_pmdp_invalidate(mm, addr); |
440 | } else { |
441 | pmdp_idte_global(mm, addr, pmdp); |
442 | } |
443 | atomic_dec(v: &mm->context.flush_count); |
444 | return old; |
445 | } |
446 | |
447 | #ifdef CONFIG_PGSTE |
448 | static int pmd_lookup(struct mm_struct *mm, unsigned long addr, pmd_t **pmdp) |
449 | { |
450 | struct vm_area_struct *vma; |
451 | pgd_t *pgd; |
452 | p4d_t *p4d; |
453 | pud_t *pud; |
454 | |
455 | /* We need a valid VMA, otherwise this is clearly a fault. */ |
456 | vma = vma_lookup(mm, addr); |
457 | if (!vma) |
458 | return -EFAULT; |
459 | |
460 | pgd = pgd_offset(mm, addr); |
461 | if (!pgd_present(*pgd)) |
462 | return -ENOENT; |
463 | |
464 | p4d = p4d_offset(pgd, addr); |
465 | if (!p4d_present(*p4d)) |
466 | return -ENOENT; |
467 | |
468 | pud = pud_offset(p4d, addr); |
469 | if (!pud_present(*pud)) |
470 | return -ENOENT; |
471 | |
472 | /* Large PUDs are not supported yet. */ |
473 | if (pud_leaf(*pud)) |
474 | return -EFAULT; |
475 | |
476 | *pmdp = pmd_offset(pud, addr); |
477 | return 0; |
478 | } |
479 | #endif |
480 | |
481 | pmd_t pmdp_xchg_direct(struct mm_struct *mm, unsigned long addr, |
482 | pmd_t *pmdp, pmd_t new) |
483 | { |
484 | pmd_t old; |
485 | |
486 | preempt_disable(); |
487 | old = pmdp_flush_direct(mm, addr, pmdp); |
488 | set_pmd(pmdp, pmd: new); |
489 | preempt_enable(); |
490 | return old; |
491 | } |
492 | EXPORT_SYMBOL(pmdp_xchg_direct); |
493 | |
494 | pmd_t pmdp_xchg_lazy(struct mm_struct *mm, unsigned long addr, |
495 | pmd_t *pmdp, pmd_t new) |
496 | { |
497 | pmd_t old; |
498 | |
499 | preempt_disable(); |
500 | old = pmdp_flush_lazy(mm, addr, pmdp); |
501 | set_pmd(pmdp, pmd: new); |
502 | preempt_enable(); |
503 | return old; |
504 | } |
505 | EXPORT_SYMBOL(pmdp_xchg_lazy); |
506 | |
507 | static inline void pudp_idte_local(struct mm_struct *mm, |
508 | unsigned long addr, pud_t *pudp) |
509 | { |
510 | if (MACHINE_HAS_TLB_GUEST) |
511 | __pudp_idte(addr, pudp, IDTE_NODAT | IDTE_GUEST_ASCE, |
512 | mm->context.asce, IDTE_LOCAL); |
513 | else |
514 | __pudp_idte(addr, pudp, 0, 0, IDTE_LOCAL); |
515 | } |
516 | |
517 | static inline void pudp_idte_global(struct mm_struct *mm, |
518 | unsigned long addr, pud_t *pudp) |
519 | { |
520 | if (MACHINE_HAS_TLB_GUEST) |
521 | __pudp_idte(addr, pudp, IDTE_NODAT | IDTE_GUEST_ASCE, |
522 | mm->context.asce, IDTE_GLOBAL); |
523 | else if (MACHINE_HAS_IDTE) |
524 | __pudp_idte(addr, pudp, 0, 0, IDTE_GLOBAL); |
525 | else |
526 | /* |
527 | * Invalid bit position is the same for pmd and pud, so we can |
528 | * re-use _pmd_csp() here |
529 | */ |
530 | __pmdp_csp((pmd_t *) pudp); |
531 | } |
532 | |
533 | static inline pud_t pudp_flush_direct(struct mm_struct *mm, |
534 | unsigned long addr, pud_t *pudp) |
535 | { |
536 | pud_t old; |
537 | |
538 | old = *pudp; |
539 | if (pud_val(old) & _REGION_ENTRY_INVALID) |
540 | return old; |
541 | atomic_inc(v: &mm->context.flush_count); |
542 | if (MACHINE_HAS_TLB_LC && |
543 | cpumask_equal(mm_cpumask(mm), cpumask_of(smp_processor_id()))) |
544 | pudp_idte_local(mm, addr, pudp); |
545 | else |
546 | pudp_idte_global(mm, addr, pudp); |
547 | atomic_dec(v: &mm->context.flush_count); |
548 | return old; |
549 | } |
550 | |
551 | pud_t pudp_xchg_direct(struct mm_struct *mm, unsigned long addr, |
552 | pud_t *pudp, pud_t new) |
553 | { |
554 | pud_t old; |
555 | |
556 | preempt_disable(); |
557 | old = pudp_flush_direct(mm, addr, pudp); |
558 | set_pud(pudp, pud: new); |
559 | preempt_enable(); |
560 | return old; |
561 | } |
562 | EXPORT_SYMBOL(pudp_xchg_direct); |
563 | |
564 | #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
565 | void pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp, |
566 | pgtable_t pgtable) |
567 | { |
568 | struct list_head *lh = (struct list_head *) pgtable; |
569 | |
570 | assert_spin_locked(pmd_lockptr(mm, pmdp)); |
571 | |
572 | /* FIFO */ |
573 | if (!pmd_huge_pte(mm, pmdp)) |
574 | INIT_LIST_HEAD(list: lh); |
575 | else |
576 | list_add(new: lh, head: (struct list_head *) pmd_huge_pte(mm, pmdp)); |
577 | pmd_huge_pte(mm, pmdp) = pgtable; |
578 | } |
579 | |
580 | pgtable_t pgtable_trans_huge_withdraw(struct mm_struct *mm, pmd_t *pmdp) |
581 | { |
582 | struct list_head *lh; |
583 | pgtable_t pgtable; |
584 | pte_t *ptep; |
585 | |
586 | assert_spin_locked(pmd_lockptr(mm, pmdp)); |
587 | |
588 | /* FIFO */ |
589 | pgtable = pmd_huge_pte(mm, pmdp); |
590 | lh = (struct list_head *) pgtable; |
591 | if (list_empty(head: lh)) |
592 | pmd_huge_pte(mm, pmdp) = NULL; |
593 | else { |
594 | pmd_huge_pte(mm, pmdp) = (pgtable_t) lh->next; |
595 | list_del(entry: lh); |
596 | } |
597 | ptep = (pte_t *) pgtable; |
598 | set_pte(ptep, __pte(_PAGE_INVALID)); |
599 | ptep++; |
600 | set_pte(ptep, __pte(_PAGE_INVALID)); |
601 | return pgtable; |
602 | } |
603 | #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ |
604 | |
605 | #ifdef CONFIG_PGSTE |
606 | void ptep_set_pte_at(struct mm_struct *mm, unsigned long addr, |
607 | pte_t *ptep, pte_t entry) |
608 | { |
609 | pgste_t pgste; |
610 | |
611 | /* the mm_has_pgste() check is done in set_pte_at() */ |
612 | preempt_disable(); |
613 | pgste = pgste_get_lock(ptep); |
614 | pgste_val(pgste) &= ~_PGSTE_GPS_ZERO; |
615 | pgste_set_key(ptep, pgste, entry, mm); |
616 | pgste = pgste_set_pte(ptep, pgste, entry); |
617 | pgste_set_unlock(ptep, pgste); |
618 | preempt_enable(); |
619 | } |
620 | |
621 | void ptep_set_notify(struct mm_struct *mm, unsigned long addr, pte_t *ptep) |
622 | { |
623 | pgste_t pgste; |
624 | |
625 | preempt_disable(); |
626 | pgste = pgste_get_lock(ptep); |
627 | pgste_val(pgste) |= PGSTE_IN_BIT; |
628 | pgste_set_unlock(ptep, pgste); |
629 | preempt_enable(); |
630 | } |
631 | |
632 | /** |
633 | * ptep_force_prot - change access rights of a locked pte |
634 | * @mm: pointer to the process mm_struct |
635 | * @addr: virtual address in the guest address space |
636 | * @ptep: pointer to the page table entry |
637 | * @prot: indicates guest access rights: PROT_NONE, PROT_READ or PROT_WRITE |
638 | * @bit: pgste bit to set (e.g. for notification) |
639 | * |
640 | * Returns 0 if the access rights were changed and -EAGAIN if the current |
641 | * and requested access rights are incompatible. |
642 | */ |
643 | int ptep_force_prot(struct mm_struct *mm, unsigned long addr, |
644 | pte_t *ptep, int prot, unsigned long bit) |
645 | { |
646 | pte_t entry; |
647 | pgste_t pgste; |
648 | int pte_i, pte_p, nodat; |
649 | |
650 | pgste = pgste_get_lock(ptep); |
651 | entry = *ptep; |
652 | /* Check pte entry after all locks have been acquired */ |
653 | pte_i = pte_val(entry) & _PAGE_INVALID; |
654 | pte_p = pte_val(entry) & _PAGE_PROTECT; |
655 | if ((pte_i && (prot != PROT_NONE)) || |
656 | (pte_p && (prot & PROT_WRITE))) { |
657 | pgste_set_unlock(ptep, pgste); |
658 | return -EAGAIN; |
659 | } |
660 | /* Change access rights and set pgste bit */ |
661 | nodat = !!(pgste_val(pgste) & _PGSTE_GPS_NODAT); |
662 | if (prot == PROT_NONE && !pte_i) { |
663 | ptep_flush_direct(mm, addr, ptep, nodat); |
664 | pgste = pgste_update_all(entry, pgste, mm); |
665 | entry = set_pte_bit(entry, __pgprot(_PAGE_INVALID)); |
666 | } |
667 | if (prot == PROT_READ && !pte_p) { |
668 | ptep_flush_direct(mm, addr, ptep, nodat); |
669 | entry = clear_pte_bit(entry, __pgprot(_PAGE_INVALID)); |
670 | entry = set_pte_bit(entry, __pgprot(_PAGE_PROTECT)); |
671 | } |
672 | pgste_val(pgste) |= bit; |
673 | pgste = pgste_set_pte(ptep, pgste, entry); |
674 | pgste_set_unlock(ptep, pgste); |
675 | return 0; |
676 | } |
677 | |
678 | int ptep_shadow_pte(struct mm_struct *mm, unsigned long saddr, |
679 | pte_t *sptep, pte_t *tptep, pte_t pte) |
680 | { |
681 | pgste_t spgste, tpgste; |
682 | pte_t spte, tpte; |
683 | int rc = -EAGAIN; |
684 | |
685 | if (!(pte_val(*tptep) & _PAGE_INVALID)) |
686 | return 0; /* already shadowed */ |
687 | spgste = pgste_get_lock(sptep); |
688 | spte = *sptep; |
689 | if (!(pte_val(spte) & _PAGE_INVALID) && |
690 | !((pte_val(spte) & _PAGE_PROTECT) && |
691 | !(pte_val(pte) & _PAGE_PROTECT))) { |
692 | pgste_val(spgste) |= PGSTE_VSIE_BIT; |
693 | tpgste = pgste_get_lock(tptep); |
694 | tpte = __pte((pte_val(spte) & PAGE_MASK) | |
695 | (pte_val(pte) & _PAGE_PROTECT)); |
696 | /* don't touch the storage key - it belongs to parent pgste */ |
697 | tpgste = pgste_set_pte(tptep, tpgste, tpte); |
698 | pgste_set_unlock(tptep, tpgste); |
699 | rc = 1; |
700 | } |
701 | pgste_set_unlock(sptep, spgste); |
702 | return rc; |
703 | } |
704 | |
705 | void ptep_unshadow_pte(struct mm_struct *mm, unsigned long saddr, pte_t *ptep) |
706 | { |
707 | pgste_t pgste; |
708 | int nodat; |
709 | |
710 | pgste = pgste_get_lock(ptep); |
711 | /* notifier is called by the caller */ |
712 | nodat = !!(pgste_val(pgste) & _PGSTE_GPS_NODAT); |
713 | ptep_flush_direct(mm, saddr, ptep, nodat); |
714 | /* don't touch the storage key - it belongs to parent pgste */ |
715 | pgste = pgste_set_pte(ptep, pgste, __pte(_PAGE_INVALID)); |
716 | pgste_set_unlock(ptep, pgste); |
717 | } |
718 | |
719 | static void ptep_zap_swap_entry(struct mm_struct *mm, swp_entry_t entry) |
720 | { |
721 | if (!non_swap_entry(entry)) |
722 | dec_mm_counter(mm, MM_SWAPENTS); |
723 | else if (is_migration_entry(entry)) { |
724 | struct folio *folio = pfn_swap_entry_folio(entry); |
725 | |
726 | dec_mm_counter(mm, mm_counter(folio)); |
727 | } |
728 | free_swap_and_cache(entry); |
729 | } |
730 | |
731 | void ptep_zap_unused(struct mm_struct *mm, unsigned long addr, |
732 | pte_t *ptep, int reset) |
733 | { |
734 | unsigned long pgstev; |
735 | pgste_t pgste; |
736 | pte_t pte; |
737 | |
738 | /* Zap unused and logically-zero pages */ |
739 | preempt_disable(); |
740 | pgste = pgste_get_lock(ptep); |
741 | pgstev = pgste_val(pgste); |
742 | pte = *ptep; |
743 | if (!reset && pte_swap(pte) && |
744 | ((pgstev & _PGSTE_GPS_USAGE_MASK) == _PGSTE_GPS_USAGE_UNUSED || |
745 | (pgstev & _PGSTE_GPS_ZERO))) { |
746 | ptep_zap_swap_entry(mm, pte_to_swp_entry(pte)); |
747 | pte_clear(mm, addr, ptep); |
748 | } |
749 | if (reset) |
750 | pgste_val(pgste) &= ~(_PGSTE_GPS_USAGE_MASK | _PGSTE_GPS_NODAT); |
751 | pgste_set_unlock(ptep, pgste); |
752 | preempt_enable(); |
753 | } |
754 | |
755 | void ptep_zap_key(struct mm_struct *mm, unsigned long addr, pte_t *ptep) |
756 | { |
757 | unsigned long ptev; |
758 | pgste_t pgste; |
759 | |
760 | /* Clear storage key ACC and F, but set R/C */ |
761 | preempt_disable(); |
762 | pgste = pgste_get_lock(ptep); |
763 | pgste_val(pgste) &= ~(PGSTE_ACC_BITS | PGSTE_FP_BIT); |
764 | pgste_val(pgste) |= PGSTE_GR_BIT | PGSTE_GC_BIT; |
765 | ptev = pte_val(*ptep); |
766 | if (!(ptev & _PAGE_INVALID) && (ptev & _PAGE_WRITE)) |
767 | page_set_storage_key(ptev & PAGE_MASK, PAGE_DEFAULT_KEY, 0); |
768 | pgste_set_unlock(ptep, pgste); |
769 | preempt_enable(); |
770 | } |
771 | |
772 | /* |
773 | * Test and reset if a guest page is dirty |
774 | */ |
775 | bool ptep_test_and_clear_uc(struct mm_struct *mm, unsigned long addr, |
776 | pte_t *ptep) |
777 | { |
778 | pgste_t pgste; |
779 | pte_t pte; |
780 | bool dirty; |
781 | int nodat; |
782 | |
783 | pgste = pgste_get_lock(ptep); |
784 | dirty = !!(pgste_val(pgste) & PGSTE_UC_BIT); |
785 | pgste_val(pgste) &= ~PGSTE_UC_BIT; |
786 | pte = *ptep; |
787 | if (dirty && (pte_val(pte) & _PAGE_PRESENT)) { |
788 | pgste = pgste_pte_notify(mm, addr, ptep, pgste); |
789 | nodat = !!(pgste_val(pgste) & _PGSTE_GPS_NODAT); |
790 | ptep_ipte_global(mm, addr, ptep, nodat); |
791 | if (MACHINE_HAS_ESOP || !(pte_val(pte) & _PAGE_WRITE)) |
792 | pte = set_pte_bit(pte, __pgprot(_PAGE_PROTECT)); |
793 | else |
794 | pte = set_pte_bit(pte, __pgprot(_PAGE_INVALID)); |
795 | set_pte(ptep, pte); |
796 | } |
797 | pgste_set_unlock(ptep, pgste); |
798 | return dirty; |
799 | } |
800 | EXPORT_SYMBOL_GPL(ptep_test_and_clear_uc); |
801 | |
802 | int set_guest_storage_key(struct mm_struct *mm, unsigned long addr, |
803 | unsigned char key, bool nq) |
804 | { |
805 | unsigned long keyul, paddr; |
806 | spinlock_t *ptl; |
807 | pgste_t old, new; |
808 | pmd_t *pmdp; |
809 | pte_t *ptep; |
810 | |
811 | /* |
812 | * If we don't have a PTE table and if there is no huge page mapped, |
813 | * we can ignore attempts to set the key to 0, because it already is 0. |
814 | */ |
815 | switch (pmd_lookup(mm, addr, &pmdp)) { |
816 | case -ENOENT: |
817 | return key ? -EFAULT : 0; |
818 | case 0: |
819 | break; |
820 | default: |
821 | return -EFAULT; |
822 | } |
823 | again: |
824 | ptl = pmd_lock(mm, pmdp); |
825 | if (!pmd_present(*pmdp)) { |
826 | spin_unlock(ptl); |
827 | return key ? -EFAULT : 0; |
828 | } |
829 | |
830 | if (pmd_leaf(*pmdp)) { |
831 | paddr = pmd_val(*pmdp) & HPAGE_MASK; |
832 | paddr |= addr & ~HPAGE_MASK; |
833 | /* |
834 | * Huge pmds need quiescing operations, they are |
835 | * always mapped. |
836 | */ |
837 | page_set_storage_key(paddr, key, 1); |
838 | spin_unlock(ptl); |
839 | return 0; |
840 | } |
841 | spin_unlock(ptl); |
842 | |
843 | ptep = pte_offset_map_lock(mm, pmdp, addr, &ptl); |
844 | if (!ptep) |
845 | goto again; |
846 | new = old = pgste_get_lock(ptep); |
847 | pgste_val(new) &= ~(PGSTE_GR_BIT | PGSTE_GC_BIT | |
848 | PGSTE_ACC_BITS | PGSTE_FP_BIT); |
849 | keyul = (unsigned long) key; |
850 | pgste_val(new) |= (keyul & (_PAGE_CHANGED | _PAGE_REFERENCED)) << 48; |
851 | pgste_val(new) |= (keyul & (_PAGE_ACC_BITS | _PAGE_FP_BIT)) << 56; |
852 | if (!(pte_val(*ptep) & _PAGE_INVALID)) { |
853 | unsigned long bits, skey; |
854 | |
855 | paddr = pte_val(*ptep) & PAGE_MASK; |
856 | skey = (unsigned long) page_get_storage_key(paddr); |
857 | bits = skey & (_PAGE_CHANGED | _PAGE_REFERENCED); |
858 | skey = key & (_PAGE_ACC_BITS | _PAGE_FP_BIT); |
859 | /* Set storage key ACC and FP */ |
860 | page_set_storage_key(paddr, skey, !nq); |
861 | /* Merge host changed & referenced into pgste */ |
862 | pgste_val(new) |= bits << 52; |
863 | } |
864 | /* changing the guest storage key is considered a change of the page */ |
865 | if ((pgste_val(new) ^ pgste_val(old)) & |
866 | (PGSTE_ACC_BITS | PGSTE_FP_BIT | PGSTE_GR_BIT | PGSTE_GC_BIT)) |
867 | pgste_val(new) |= PGSTE_UC_BIT; |
868 | |
869 | pgste_set_unlock(ptep, new); |
870 | pte_unmap_unlock(ptep, ptl); |
871 | return 0; |
872 | } |
873 | EXPORT_SYMBOL(set_guest_storage_key); |
874 | |
875 | /* |
876 | * Conditionally set a guest storage key (handling csske). |
877 | * oldkey will be updated when either mr or mc is set and a pointer is given. |
878 | * |
879 | * Returns 0 if a guests storage key update wasn't necessary, 1 if the guest |
880 | * storage key was updated and -EFAULT on access errors. |
881 | */ |
882 | int cond_set_guest_storage_key(struct mm_struct *mm, unsigned long addr, |
883 | unsigned char key, unsigned char *oldkey, |
884 | bool nq, bool mr, bool mc) |
885 | { |
886 | unsigned char tmp, mask = _PAGE_ACC_BITS | _PAGE_FP_BIT; |
887 | int rc; |
888 | |
889 | /* we can drop the pgste lock between getting and setting the key */ |
890 | if (mr | mc) { |
891 | rc = get_guest_storage_key(current->mm, addr, &tmp); |
892 | if (rc) |
893 | return rc; |
894 | if (oldkey) |
895 | *oldkey = tmp; |
896 | if (!mr) |
897 | mask |= _PAGE_REFERENCED; |
898 | if (!mc) |
899 | mask |= _PAGE_CHANGED; |
900 | if (!((tmp ^ key) & mask)) |
901 | return 0; |
902 | } |
903 | rc = set_guest_storage_key(current->mm, addr, key, nq); |
904 | return rc < 0 ? rc : 1; |
905 | } |
906 | EXPORT_SYMBOL(cond_set_guest_storage_key); |
907 | |
908 | /* |
909 | * Reset a guest reference bit (rrbe), returning the reference and changed bit. |
910 | * |
911 | * Returns < 0 in case of error, otherwise the cc to be reported to the guest. |
912 | */ |
913 | int reset_guest_reference_bit(struct mm_struct *mm, unsigned long addr) |
914 | { |
915 | spinlock_t *ptl; |
916 | unsigned long paddr; |
917 | pgste_t old, new; |
918 | pmd_t *pmdp; |
919 | pte_t *ptep; |
920 | int cc = 0; |
921 | |
922 | /* |
923 | * If we don't have a PTE table and if there is no huge page mapped, |
924 | * the storage key is 0 and there is nothing for us to do. |
925 | */ |
926 | switch (pmd_lookup(mm, addr, &pmdp)) { |
927 | case -ENOENT: |
928 | return 0; |
929 | case 0: |
930 | break; |
931 | default: |
932 | return -EFAULT; |
933 | } |
934 | again: |
935 | ptl = pmd_lock(mm, pmdp); |
936 | if (!pmd_present(*pmdp)) { |
937 | spin_unlock(ptl); |
938 | return 0; |
939 | } |
940 | |
941 | if (pmd_leaf(*pmdp)) { |
942 | paddr = pmd_val(*pmdp) & HPAGE_MASK; |
943 | paddr |= addr & ~HPAGE_MASK; |
944 | cc = page_reset_referenced(paddr); |
945 | spin_unlock(ptl); |
946 | return cc; |
947 | } |
948 | spin_unlock(ptl); |
949 | |
950 | ptep = pte_offset_map_lock(mm, pmdp, addr, &ptl); |
951 | if (!ptep) |
952 | goto again; |
953 | new = old = pgste_get_lock(ptep); |
954 | /* Reset guest reference bit only */ |
955 | pgste_val(new) &= ~PGSTE_GR_BIT; |
956 | |
957 | if (!(pte_val(*ptep) & _PAGE_INVALID)) { |
958 | paddr = pte_val(*ptep) & PAGE_MASK; |
959 | cc = page_reset_referenced(paddr); |
960 | /* Merge real referenced bit into host-set */ |
961 | pgste_val(new) |= ((unsigned long) cc << 53) & PGSTE_HR_BIT; |
962 | } |
963 | /* Reflect guest's logical view, not physical */ |
964 | cc |= (pgste_val(old) & (PGSTE_GR_BIT | PGSTE_GC_BIT)) >> 49; |
965 | /* Changing the guest storage key is considered a change of the page */ |
966 | if ((pgste_val(new) ^ pgste_val(old)) & PGSTE_GR_BIT) |
967 | pgste_val(new) |= PGSTE_UC_BIT; |
968 | |
969 | pgste_set_unlock(ptep, new); |
970 | pte_unmap_unlock(ptep, ptl); |
971 | return cc; |
972 | } |
973 | EXPORT_SYMBOL(reset_guest_reference_bit); |
974 | |
975 | int get_guest_storage_key(struct mm_struct *mm, unsigned long addr, |
976 | unsigned char *key) |
977 | { |
978 | unsigned long paddr; |
979 | spinlock_t *ptl; |
980 | pgste_t pgste; |
981 | pmd_t *pmdp; |
982 | pte_t *ptep; |
983 | |
984 | /* |
985 | * If we don't have a PTE table and if there is no huge page mapped, |
986 | * the storage key is 0. |
987 | */ |
988 | *key = 0; |
989 | |
990 | switch (pmd_lookup(mm, addr, &pmdp)) { |
991 | case -ENOENT: |
992 | return 0; |
993 | case 0: |
994 | break; |
995 | default: |
996 | return -EFAULT; |
997 | } |
998 | again: |
999 | ptl = pmd_lock(mm, pmdp); |
1000 | if (!pmd_present(*pmdp)) { |
1001 | spin_unlock(ptl); |
1002 | return 0; |
1003 | } |
1004 | |
1005 | if (pmd_leaf(*pmdp)) { |
1006 | paddr = pmd_val(*pmdp) & HPAGE_MASK; |
1007 | paddr |= addr & ~HPAGE_MASK; |
1008 | *key = page_get_storage_key(paddr); |
1009 | spin_unlock(ptl); |
1010 | return 0; |
1011 | } |
1012 | spin_unlock(ptl); |
1013 | |
1014 | ptep = pte_offset_map_lock(mm, pmdp, addr, &ptl); |
1015 | if (!ptep) |
1016 | goto again; |
1017 | pgste = pgste_get_lock(ptep); |
1018 | *key = (pgste_val(pgste) & (PGSTE_ACC_BITS | PGSTE_FP_BIT)) >> 56; |
1019 | paddr = pte_val(*ptep) & PAGE_MASK; |
1020 | if (!(pte_val(*ptep) & _PAGE_INVALID)) |
1021 | *key = page_get_storage_key(paddr); |
1022 | /* Reflect guest's logical view, not physical */ |
1023 | *key |= (pgste_val(pgste) & (PGSTE_GR_BIT | PGSTE_GC_BIT)) >> 48; |
1024 | pgste_set_unlock(ptep, pgste); |
1025 | pte_unmap_unlock(ptep, ptl); |
1026 | return 0; |
1027 | } |
1028 | EXPORT_SYMBOL(get_guest_storage_key); |
1029 | |
1030 | /** |
1031 | * pgste_perform_essa - perform ESSA actions on the PGSTE. |
1032 | * @mm: the memory context. It must have PGSTEs, no check is performed here! |
1033 | * @hva: the host virtual address of the page whose PGSTE is to be processed |
1034 | * @orc: the specific action to perform, see the ESSA_SET_* macros. |
1035 | * @oldpte: the PTE will be saved there if the pointer is not NULL. |
1036 | * @oldpgste: the old PGSTE will be saved there if the pointer is not NULL. |
1037 | * |
1038 | * Return: 1 if the page is to be added to the CBRL, otherwise 0, |
1039 | * or < 0 in case of error. -EINVAL is returned for invalid values |
1040 | * of orc, -EFAULT for invalid addresses. |
1041 | */ |
1042 | int pgste_perform_essa(struct mm_struct *mm, unsigned long hva, int orc, |
1043 | unsigned long *oldpte, unsigned long *oldpgste) |
1044 | { |
1045 | struct vm_area_struct *vma; |
1046 | unsigned long pgstev; |
1047 | spinlock_t *ptl; |
1048 | pgste_t pgste; |
1049 | pte_t *ptep; |
1050 | int res = 0; |
1051 | |
1052 | WARN_ON_ONCE(orc > ESSA_MAX); |
1053 | if (unlikely(orc > ESSA_MAX)) |
1054 | return -EINVAL; |
1055 | |
1056 | vma = vma_lookup(mm, hva); |
1057 | if (!vma || is_vm_hugetlb_page(vma)) |
1058 | return -EFAULT; |
1059 | ptep = get_locked_pte(mm, hva, &ptl); |
1060 | if (unlikely(!ptep)) |
1061 | return -EFAULT; |
1062 | pgste = pgste_get_lock(ptep); |
1063 | pgstev = pgste_val(pgste); |
1064 | if (oldpte) |
1065 | *oldpte = pte_val(*ptep); |
1066 | if (oldpgste) |
1067 | *oldpgste = pgstev; |
1068 | |
1069 | switch (orc) { |
1070 | case ESSA_GET_STATE: |
1071 | break; |
1072 | case ESSA_SET_STABLE: |
1073 | pgstev &= ~(_PGSTE_GPS_USAGE_MASK | _PGSTE_GPS_NODAT); |
1074 | pgstev |= _PGSTE_GPS_USAGE_STABLE; |
1075 | break; |
1076 | case ESSA_SET_UNUSED: |
1077 | pgstev &= ~_PGSTE_GPS_USAGE_MASK; |
1078 | pgstev |= _PGSTE_GPS_USAGE_UNUSED; |
1079 | if (pte_val(*ptep) & _PAGE_INVALID) |
1080 | res = 1; |
1081 | break; |
1082 | case ESSA_SET_VOLATILE: |
1083 | pgstev &= ~_PGSTE_GPS_USAGE_MASK; |
1084 | pgstev |= _PGSTE_GPS_USAGE_VOLATILE; |
1085 | if (pte_val(*ptep) & _PAGE_INVALID) |
1086 | res = 1; |
1087 | break; |
1088 | case ESSA_SET_POT_VOLATILE: |
1089 | pgstev &= ~_PGSTE_GPS_USAGE_MASK; |
1090 | if (!(pte_val(*ptep) & _PAGE_INVALID)) { |
1091 | pgstev |= _PGSTE_GPS_USAGE_POT_VOLATILE; |
1092 | break; |
1093 | } |
1094 | if (pgstev & _PGSTE_GPS_ZERO) { |
1095 | pgstev |= _PGSTE_GPS_USAGE_VOLATILE; |
1096 | break; |
1097 | } |
1098 | if (!(pgstev & PGSTE_GC_BIT)) { |
1099 | pgstev |= _PGSTE_GPS_USAGE_VOLATILE; |
1100 | res = 1; |
1101 | break; |
1102 | } |
1103 | break; |
1104 | case ESSA_SET_STABLE_RESIDENT: |
1105 | pgstev &= ~_PGSTE_GPS_USAGE_MASK; |
1106 | pgstev |= _PGSTE_GPS_USAGE_STABLE; |
1107 | /* |
1108 | * Since the resident state can go away any time after this |
1109 | * call, we will not make this page resident. We can revisit |
1110 | * this decision if a guest will ever start using this. |
1111 | */ |
1112 | break; |
1113 | case ESSA_SET_STABLE_IF_RESIDENT: |
1114 | if (!(pte_val(*ptep) & _PAGE_INVALID)) { |
1115 | pgstev &= ~_PGSTE_GPS_USAGE_MASK; |
1116 | pgstev |= _PGSTE_GPS_USAGE_STABLE; |
1117 | } |
1118 | break; |
1119 | case ESSA_SET_STABLE_NODAT: |
1120 | pgstev &= ~_PGSTE_GPS_USAGE_MASK; |
1121 | pgstev |= _PGSTE_GPS_USAGE_STABLE | _PGSTE_GPS_NODAT; |
1122 | break; |
1123 | default: |
1124 | /* we should never get here! */ |
1125 | break; |
1126 | } |
1127 | /* If we are discarding a page, set it to logical zero */ |
1128 | if (res) |
1129 | pgstev |= _PGSTE_GPS_ZERO; |
1130 | |
1131 | pgste_val(pgste) = pgstev; |
1132 | pgste_set_unlock(ptep, pgste); |
1133 | pte_unmap_unlock(ptep, ptl); |
1134 | return res; |
1135 | } |
1136 | EXPORT_SYMBOL(pgste_perform_essa); |
1137 | |
1138 | /** |
1139 | * set_pgste_bits - set specific PGSTE bits. |
1140 | * @mm: the memory context. It must have PGSTEs, no check is performed here! |
1141 | * @hva: the host virtual address of the page whose PGSTE is to be processed |
1142 | * @bits: a bitmask representing the bits that will be touched |
1143 | * @value: the values of the bits to be written. Only the bits in the mask |
1144 | * will be written. |
1145 | * |
1146 | * Return: 0 on success, < 0 in case of error. |
1147 | */ |
1148 | int set_pgste_bits(struct mm_struct *mm, unsigned long hva, |
1149 | unsigned long bits, unsigned long value) |
1150 | { |
1151 | struct vm_area_struct *vma; |
1152 | spinlock_t *ptl; |
1153 | pgste_t new; |
1154 | pte_t *ptep; |
1155 | |
1156 | vma = vma_lookup(mm, hva); |
1157 | if (!vma || is_vm_hugetlb_page(vma)) |
1158 | return -EFAULT; |
1159 | ptep = get_locked_pte(mm, hva, &ptl); |
1160 | if (unlikely(!ptep)) |
1161 | return -EFAULT; |
1162 | new = pgste_get_lock(ptep); |
1163 | |
1164 | pgste_val(new) &= ~bits; |
1165 | pgste_val(new) |= value & bits; |
1166 | |
1167 | pgste_set_unlock(ptep, new); |
1168 | pte_unmap_unlock(ptep, ptl); |
1169 | return 0; |
1170 | } |
1171 | EXPORT_SYMBOL(set_pgste_bits); |
1172 | |
1173 | /** |
1174 | * get_pgste - get the current PGSTE for the given address. |
1175 | * @mm: the memory context. It must have PGSTEs, no check is performed here! |
1176 | * @hva: the host virtual address of the page whose PGSTE is to be processed |
1177 | * @pgstep: will be written with the current PGSTE for the given address. |
1178 | * |
1179 | * Return: 0 on success, < 0 in case of error. |
1180 | */ |
1181 | int get_pgste(struct mm_struct *mm, unsigned long hva, unsigned long *pgstep) |
1182 | { |
1183 | struct vm_area_struct *vma; |
1184 | spinlock_t *ptl; |
1185 | pte_t *ptep; |
1186 | |
1187 | vma = vma_lookup(mm, hva); |
1188 | if (!vma || is_vm_hugetlb_page(vma)) |
1189 | return -EFAULT; |
1190 | ptep = get_locked_pte(mm, hva, &ptl); |
1191 | if (unlikely(!ptep)) |
1192 | return -EFAULT; |
1193 | *pgstep = pgste_val(pgste_get(ptep)); |
1194 | pte_unmap_unlock(ptep, ptl); |
1195 | return 0; |
1196 | } |
1197 | EXPORT_SYMBOL(get_pgste); |
1198 | #endif |
1199 | |