1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * native hashtable management.
4 *
5 * SMP scalability work:
6 * Copyright (C) 2001 Anton Blanchard <anton@au.ibm.com>, IBM
7 */
8
9#undef DEBUG_LOW
10
11#include <linux/spinlock.h>
12#include <linux/bitops.h>
13#include <linux/of.h>
14#include <linux/processor.h>
15#include <linux/threads.h>
16#include <linux/smp.h>
17#include <linux/pgtable.h>
18
19#include <asm/machdep.h>
20#include <asm/mmu.h>
21#include <asm/mmu_context.h>
22#include <asm/trace.h>
23#include <asm/tlb.h>
24#include <asm/cputable.h>
25#include <asm/udbg.h>
26#include <asm/kexec.h>
27#include <asm/ppc-opcode.h>
28#include <asm/feature-fixups.h>
29
30#include <misc/cxl-base.h>
31
32#ifdef DEBUG_LOW
33#define DBG_LOW(fmt...) udbg_printf(fmt)
34#else
35#define DBG_LOW(fmt...)
36#endif
37
38#ifdef __BIG_ENDIAN__
39#define HPTE_LOCK_BIT 3
40#else
41#define HPTE_LOCK_BIT (56+3)
42#endif
43
44static DEFINE_RAW_SPINLOCK(native_tlbie_lock);
45
46#ifdef CONFIG_LOCKDEP
47static struct lockdep_map hpte_lock_map =
48 STATIC_LOCKDEP_MAP_INIT("hpte_lock", &hpte_lock_map);
49
50static void acquire_hpte_lock(void)
51{
52 lock_map_acquire(&hpte_lock_map);
53}
54
55static void release_hpte_lock(void)
56{
57 lock_map_release(&hpte_lock_map);
58}
59#else
60static void acquire_hpte_lock(void)
61{
62}
63
64static void release_hpte_lock(void)
65{
66}
67#endif
68
69static inline unsigned long ___tlbie(unsigned long vpn, int psize,
70 int apsize, int ssize)
71{
72 unsigned long va;
73 unsigned int penc;
74 unsigned long sllp;
75
76 /*
77 * We need 14 to 65 bits of va for a tlibe of 4K page
78 * With vpn we ignore the lower VPN_SHIFT bits already.
79 * And top two bits are already ignored because we can
80 * only accomodate 76 bits in a 64 bit vpn with a VPN_SHIFT
81 * of 12.
82 */
83 va = vpn << VPN_SHIFT;
84 /*
85 * clear top 16 bits of 64bit va, non SLS segment
86 * Older versions of the architecture (2.02 and earler) require the
87 * masking of the top 16 bits.
88 */
89 if (mmu_has_feature(MMU_FTR_TLBIE_CROP_VA))
90 va &= ~(0xffffULL << 48);
91
92 switch (psize) {
93 case MMU_PAGE_4K:
94 /* clear out bits after (52) [0....52.....63] */
95 va &= ~((1ul << (64 - 52)) - 1);
96 va |= ssize << 8;
97 sllp = get_sllp_encoding(apsize);
98 va |= sllp << 5;
99 asm volatile(ASM_FTR_IFCLR("tlbie %0,0", PPC_TLBIE(%1,%0), %2)
100 : : "r" (va), "r"(0), "i" (CPU_FTR_ARCH_206)
101 : "memory");
102 break;
103 default:
104 /* We need 14 to 14 + i bits of va */
105 penc = mmu_psize_defs[psize].penc[apsize];
106 va &= ~((1ul << mmu_psize_defs[apsize].shift) - 1);
107 va |= penc << 12;
108 va |= ssize << 8;
109 /*
110 * AVAL bits:
111 * We don't need all the bits, but rest of the bits
112 * must be ignored by the processor.
113 * vpn cover upto 65 bits of va. (0...65) and we need
114 * 58..64 bits of va.
115 */
116 va |= (vpn & 0xfe); /* AVAL */
117 va |= 1; /* L */
118 asm volatile(ASM_FTR_IFCLR("tlbie %0,1", PPC_TLBIE(%1,%0), %2)
119 : : "r" (va), "r"(0), "i" (CPU_FTR_ARCH_206)
120 : "memory");
121 break;
122 }
123 return va;
124}
125
126static inline void fixup_tlbie_vpn(unsigned long vpn, int psize,
127 int apsize, int ssize)
128{
129 if (cpu_has_feature(CPU_FTR_P9_TLBIE_ERAT_BUG)) {
130 /* Radix flush for a hash guest */
131
132 unsigned long rb,rs,prs,r,ric;
133
134 rb = PPC_BIT(52); /* IS = 2 */
135 rs = 0; /* lpid = 0 */
136 prs = 0; /* partition scoped */
137 r = 1; /* radix format */
138 ric = 0; /* RIC_FLSUH_TLB */
139
140 /*
141 * Need the extra ptesync to make sure we don't
142 * re-order the tlbie
143 */
144 asm volatile("ptesync": : :"memory");
145 asm volatile(PPC_TLBIE_5(%0, %4, %3, %2, %1)
146 : : "r"(rb), "i"(r), "i"(prs),
147 "i"(ric), "r"(rs) : "memory");
148 }
149
150
151 if (cpu_has_feature(CPU_FTR_P9_TLBIE_STQ_BUG)) {
152 /* Need the extra ptesync to ensure we don't reorder tlbie*/
153 asm volatile("ptesync": : :"memory");
154 ___tlbie(vpn, psize, apsize, ssize);
155 }
156}
157
158static inline void __tlbie(unsigned long vpn, int psize, int apsize, int ssize)
159{
160 unsigned long rb;
161
162 rb = ___tlbie(vpn, psize, apsize, ssize);
163 trace_tlbie(0, 0, rb, 0, 0, 0, 0);
164}
165
166static inline void __tlbiel(unsigned long vpn, int psize, int apsize, int ssize)
167{
168 unsigned long va;
169 unsigned int penc;
170 unsigned long sllp;
171
172 /* VPN_SHIFT can be atmost 12 */
173 va = vpn << VPN_SHIFT;
174 /*
175 * clear top 16 bits of 64 bit va, non SLS segment
176 * Older versions of the architecture (2.02 and earler) require the
177 * masking of the top 16 bits.
178 */
179 if (mmu_has_feature(MMU_FTR_TLBIE_CROP_VA))
180 va &= ~(0xffffULL << 48);
181
182 switch (psize) {
183 case MMU_PAGE_4K:
184 /* clear out bits after(52) [0....52.....63] */
185 va &= ~((1ul << (64 - 52)) - 1);
186 va |= ssize << 8;
187 sllp = get_sllp_encoding(apsize);
188 va |= sllp << 5;
189 asm volatile(ASM_FTR_IFSET("tlbiel %0", PPC_TLBIEL_v205(%0, 0), %1)
190 : : "r" (va), "i" (CPU_FTR_ARCH_206)
191 : "memory");
192 break;
193 default:
194 /* We need 14 to 14 + i bits of va */
195 penc = mmu_psize_defs[psize].penc[apsize];
196 va &= ~((1ul << mmu_psize_defs[apsize].shift) - 1);
197 va |= penc << 12;
198 va |= ssize << 8;
199 /*
200 * AVAL bits:
201 * We don't need all the bits, but rest of the bits
202 * must be ignored by the processor.
203 * vpn cover upto 65 bits of va. (0...65) and we need
204 * 58..64 bits of va.
205 */
206 va |= (vpn & 0xfe);
207 va |= 1; /* L */
208 asm volatile(ASM_FTR_IFSET("tlbiel %0", PPC_TLBIEL_v205(%0, 1), %1)
209 : : "r" (va), "i" (CPU_FTR_ARCH_206)
210 : "memory");
211 break;
212 }
213 trace_tlbie(0, 1, va, 0, 0, 0, 0);
214
215}
216
217static inline void tlbie(unsigned long vpn, int psize, int apsize,
218 int ssize, int local)
219{
220 unsigned int use_local;
221 int lock_tlbie = !mmu_has_feature(MMU_FTR_LOCKLESS_TLBIE);
222
223 use_local = local && mmu_has_feature(MMU_FTR_TLBIEL) && !cxl_ctx_in_use();
224
225 if (use_local)
226 use_local = mmu_psize_defs[psize].tlbiel;
227 if (lock_tlbie && !use_local)
228 raw_spin_lock(&native_tlbie_lock);
229 asm volatile("ptesync": : :"memory");
230 if (use_local) {
231 __tlbiel(vpn, psize, apsize, ssize);
232 ppc_after_tlbiel_barrier();
233 } else {
234 __tlbie(vpn, psize, apsize, ssize);
235 fixup_tlbie_vpn(vpn, psize, apsize, ssize);
236 asm volatile("eieio; tlbsync; ptesync": : :"memory");
237 }
238 if (lock_tlbie && !use_local)
239 raw_spin_unlock(&native_tlbie_lock);
240}
241
242static inline void native_lock_hpte(struct hash_pte *hptep)
243{
244 unsigned long *word = (unsigned long *)&hptep->v;
245
246 acquire_hpte_lock();
247 while (1) {
248 if (!test_and_set_bit_lock(HPTE_LOCK_BIT, addr: word))
249 break;
250 spin_begin();
251 while(test_bit(HPTE_LOCK_BIT, word))
252 spin_cpu_relax();
253 spin_end();
254 }
255}
256
257static inline void native_unlock_hpte(struct hash_pte *hptep)
258{
259 unsigned long *word = (unsigned long *)&hptep->v;
260
261 release_hpte_lock();
262 clear_bit_unlock(HPTE_LOCK_BIT, addr: word);
263}
264
265static long native_hpte_insert(unsigned long hpte_group, unsigned long vpn,
266 unsigned long pa, unsigned long rflags,
267 unsigned long vflags, int psize, int apsize, int ssize)
268{
269 struct hash_pte *hptep = htab_address + hpte_group;
270 unsigned long hpte_v, hpte_r;
271 unsigned long flags;
272 int i;
273
274 local_irq_save(flags);
275
276 if (!(vflags & HPTE_V_BOLTED)) {
277 DBG_LOW(" insert(group=%lx, vpn=%016lx, pa=%016lx,"
278 " rflags=%lx, vflags=%lx, psize=%d)\n",
279 hpte_group, vpn, pa, rflags, vflags, psize);
280 }
281
282 for (i = 0; i < HPTES_PER_GROUP; i++) {
283 if (! (be64_to_cpu(hptep->v) & HPTE_V_VALID)) {
284 /* retry with lock held */
285 native_lock_hpte(hptep);
286 if (! (be64_to_cpu(hptep->v) & HPTE_V_VALID))
287 break;
288 native_unlock_hpte(hptep);
289 }
290
291 hptep++;
292 }
293
294 if (i == HPTES_PER_GROUP) {
295 local_irq_restore(flags);
296 return -1;
297 }
298
299 hpte_v = hpte_encode_v(vpn, psize, apsize, ssize) | vflags | HPTE_V_VALID;
300 hpte_r = hpte_encode_r(pa, psize, apsize) | rflags;
301
302 if (!(vflags & HPTE_V_BOLTED)) {
303 DBG_LOW(" i=%x hpte_v=%016lx, hpte_r=%016lx\n",
304 i, hpte_v, hpte_r);
305 }
306
307 if (cpu_has_feature(CPU_FTR_ARCH_300)) {
308 hpte_r = hpte_old_to_new_r(hpte_v, hpte_r);
309 hpte_v = hpte_old_to_new_v(hpte_v);
310 }
311
312 hptep->r = cpu_to_be64(hpte_r);
313 /* Guarantee the second dword is visible before the valid bit */
314 eieio();
315 /*
316 * Now set the first dword including the valid bit
317 * NOTE: this also unlocks the hpte
318 */
319 release_hpte_lock();
320 hptep->v = cpu_to_be64(hpte_v);
321
322 __asm__ __volatile__ ("ptesync" : : : "memory");
323
324 local_irq_restore(flags);
325
326 return i | (!!(vflags & HPTE_V_SECONDARY) << 3);
327}
328
329static long native_hpte_remove(unsigned long hpte_group)
330{
331 unsigned long hpte_v, flags;
332 struct hash_pte *hptep;
333 int i;
334 int slot_offset;
335
336 local_irq_save(flags);
337
338 DBG_LOW(" remove(group=%lx)\n", hpte_group);
339
340 /* pick a random entry to start at */
341 slot_offset = mftb() & 0x7;
342
343 for (i = 0; i < HPTES_PER_GROUP; i++) {
344 hptep = htab_address + hpte_group + slot_offset;
345 hpte_v = be64_to_cpu(hptep->v);
346
347 if ((hpte_v & HPTE_V_VALID) && !(hpte_v & HPTE_V_BOLTED)) {
348 /* retry with lock held */
349 native_lock_hpte(hptep);
350 hpte_v = be64_to_cpu(hptep->v);
351 if ((hpte_v & HPTE_V_VALID)
352 && !(hpte_v & HPTE_V_BOLTED))
353 break;
354 native_unlock_hpte(hptep);
355 }
356
357 slot_offset++;
358 slot_offset &= 0x7;
359 }
360
361 if (i == HPTES_PER_GROUP) {
362 i = -1;
363 goto out;
364 }
365
366 /* Invalidate the hpte. NOTE: this also unlocks it */
367 release_hpte_lock();
368 hptep->v = 0;
369out:
370 local_irq_restore(flags);
371 return i;
372}
373
374static long native_hpte_updatepp(unsigned long slot, unsigned long newpp,
375 unsigned long vpn, int bpsize,
376 int apsize, int ssize, unsigned long flags)
377{
378 struct hash_pte *hptep = htab_address + slot;
379 unsigned long hpte_v, want_v;
380 int ret = 0, local = 0;
381 unsigned long irqflags;
382
383 local_irq_save(irqflags);
384
385 want_v = hpte_encode_avpn(vpn, bpsize, ssize);
386
387 DBG_LOW(" update(vpn=%016lx, avpnv=%016lx, group=%lx, newpp=%lx)",
388 vpn, want_v & HPTE_V_AVPN, slot, newpp);
389
390 hpte_v = hpte_get_old_v(hptep);
391 /*
392 * We need to invalidate the TLB always because hpte_remove doesn't do
393 * a tlb invalidate. If a hash bucket gets full, we "evict" a more/less
394 * random entry from it. When we do that we don't invalidate the TLB
395 * (hpte_remove) because we assume the old translation is still
396 * technically "valid".
397 */
398 if (!HPTE_V_COMPARE(hpte_v, want_v) || !(hpte_v & HPTE_V_VALID)) {
399 DBG_LOW(" -> miss\n");
400 ret = -1;
401 } else {
402 native_lock_hpte(hptep);
403 /* recheck with locks held */
404 hpte_v = hpte_get_old_v(hptep);
405 if (unlikely(!HPTE_V_COMPARE(hpte_v, want_v) ||
406 !(hpte_v & HPTE_V_VALID))) {
407 ret = -1;
408 } else {
409 DBG_LOW(" -> hit\n");
410 /* Update the HPTE */
411 hptep->r = cpu_to_be64((be64_to_cpu(hptep->r) &
412 ~(HPTE_R_PPP | HPTE_R_N)) |
413 (newpp & (HPTE_R_PPP | HPTE_R_N |
414 HPTE_R_C)));
415 }
416 native_unlock_hpte(hptep);
417 }
418
419 if (flags & HPTE_LOCAL_UPDATE)
420 local = 1;
421 /*
422 * Ensure it is out of the tlb too if it is not a nohpte fault
423 */
424 if (!(flags & HPTE_NOHPTE_UPDATE))
425 tlbie(vpn, psize: bpsize, apsize, ssize, local);
426
427 local_irq_restore(irqflags);
428
429 return ret;
430}
431
432static long __native_hpte_find(unsigned long want_v, unsigned long slot)
433{
434 struct hash_pte *hptep;
435 unsigned long hpte_v;
436 unsigned long i;
437
438 for (i = 0; i < HPTES_PER_GROUP; i++) {
439
440 hptep = htab_address + slot;
441 hpte_v = hpte_get_old_v(hptep);
442 if (HPTE_V_COMPARE(hpte_v, want_v) && (hpte_v & HPTE_V_VALID))
443 /* HPTE matches */
444 return slot;
445 ++slot;
446 }
447
448 return -1;
449}
450
451static long native_hpte_find(unsigned long vpn, int psize, int ssize)
452{
453 unsigned long hpte_group;
454 unsigned long want_v;
455 unsigned long hash;
456 long slot;
457
458 hash = hpt_hash(vpn, mmu_psize_defs[psize].shift, ssize);
459 want_v = hpte_encode_avpn(vpn, psize, ssize);
460
461 /*
462 * We try to keep bolted entries always in primary hash
463 * But in some case we can find them in secondary too.
464 */
465 hpte_group = (hash & htab_hash_mask) * HPTES_PER_GROUP;
466 slot = __native_hpte_find(want_v, slot: hpte_group);
467 if (slot < 0) {
468 /* Try in secondary */
469 hpte_group = (~hash & htab_hash_mask) * HPTES_PER_GROUP;
470 slot = __native_hpte_find(want_v, slot: hpte_group);
471 if (slot < 0)
472 return -1;
473 }
474
475 return slot;
476}
477
478/*
479 * Update the page protection bits. Intended to be used to create
480 * guard pages for kernel data structures on pages which are bolted
481 * in the HPT. Assumes pages being operated on will not be stolen.
482 *
483 * No need to lock here because we should be the only user.
484 */
485static void native_hpte_updateboltedpp(unsigned long newpp, unsigned long ea,
486 int psize, int ssize)
487{
488 unsigned long vpn;
489 unsigned long vsid;
490 long slot;
491 struct hash_pte *hptep;
492 unsigned long flags;
493
494 local_irq_save(flags);
495
496 vsid = get_kernel_vsid(ea, ssize);
497 vpn = hpt_vpn(ea, vsid, ssize);
498
499 slot = native_hpte_find(vpn, psize, ssize);
500 if (slot == -1)
501 panic(fmt: "could not find page to bolt\n");
502 hptep = htab_address + slot;
503
504 /* Update the HPTE */
505 hptep->r = cpu_to_be64((be64_to_cpu(hptep->r) &
506 ~(HPTE_R_PPP | HPTE_R_N)) |
507 (newpp & (HPTE_R_PPP | HPTE_R_N)));
508 /*
509 * Ensure it is out of the tlb too. Bolted entries base and
510 * actual page size will be same.
511 */
512 tlbie(vpn, psize, apsize: psize, ssize, local: 0);
513
514 local_irq_restore(flags);
515}
516
517/*
518 * Remove a bolted kernel entry. Memory hotplug uses this.
519 *
520 * No need to lock here because we should be the only user.
521 */
522static int native_hpte_removebolted(unsigned long ea, int psize, int ssize)
523{
524 unsigned long vpn;
525 unsigned long vsid;
526 long slot;
527 struct hash_pte *hptep;
528 unsigned long flags;
529
530 local_irq_save(flags);
531
532 vsid = get_kernel_vsid(ea, ssize);
533 vpn = hpt_vpn(ea, vsid, ssize);
534
535 slot = native_hpte_find(vpn, psize, ssize);
536 if (slot == -1)
537 return -ENOENT;
538
539 hptep = htab_address + slot;
540
541 VM_WARN_ON(!(be64_to_cpu(hptep->v) & HPTE_V_BOLTED));
542
543 /* Invalidate the hpte */
544 hptep->v = 0;
545
546 /* Invalidate the TLB */
547 tlbie(vpn, psize, apsize: psize, ssize, local: 0);
548
549 local_irq_restore(flags);
550
551 return 0;
552}
553
554
555static void native_hpte_invalidate(unsigned long slot, unsigned long vpn,
556 int bpsize, int apsize, int ssize, int local)
557{
558 struct hash_pte *hptep = htab_address + slot;
559 unsigned long hpte_v;
560 unsigned long want_v;
561 unsigned long flags;
562
563 local_irq_save(flags);
564
565 DBG_LOW(" invalidate(vpn=%016lx, hash: %lx)\n", vpn, slot);
566
567 want_v = hpte_encode_avpn(vpn, bpsize, ssize);
568 hpte_v = hpte_get_old_v(hptep);
569
570 if (HPTE_V_COMPARE(hpte_v, want_v) && (hpte_v & HPTE_V_VALID)) {
571 native_lock_hpte(hptep);
572 /* recheck with locks held */
573 hpte_v = hpte_get_old_v(hptep);
574
575 if (HPTE_V_COMPARE(hpte_v, want_v) && (hpte_v & HPTE_V_VALID)) {
576 /* Invalidate the hpte. NOTE: this also unlocks it */
577 release_hpte_lock();
578 hptep->v = 0;
579 } else
580 native_unlock_hpte(hptep);
581 }
582 /*
583 * We need to invalidate the TLB always because hpte_remove doesn't do
584 * a tlb invalidate. If a hash bucket gets full, we "evict" a more/less
585 * random entry from it. When we do that we don't invalidate the TLB
586 * (hpte_remove) because we assume the old translation is still
587 * technically "valid".
588 */
589 tlbie(vpn, psize: bpsize, apsize, ssize, local);
590
591 local_irq_restore(flags);
592}
593
594#ifdef CONFIG_TRANSPARENT_HUGEPAGE
595static void native_hugepage_invalidate(unsigned long vsid,
596 unsigned long addr,
597 unsigned char *hpte_slot_array,
598 int psize, int ssize, int local)
599{
600 int i;
601 struct hash_pte *hptep;
602 int actual_psize = MMU_PAGE_16M;
603 unsigned int max_hpte_count, valid;
604 unsigned long flags, s_addr = addr;
605 unsigned long hpte_v, want_v, shift;
606 unsigned long hidx, vpn = 0, hash, slot;
607
608 shift = mmu_psize_defs[psize].shift;
609 max_hpte_count = 1U << (PMD_SHIFT - shift);
610
611 local_irq_save(flags);
612 for (i = 0; i < max_hpte_count; i++) {
613 valid = hpte_valid(hpte_slot_array, i);
614 if (!valid)
615 continue;
616 hidx = hpte_hash_index(hpte_slot_array, i);
617
618 /* get the vpn */
619 addr = s_addr + (i * (1ul << shift));
620 vpn = hpt_vpn(addr, vsid, ssize);
621 hash = hpt_hash(vpn, shift, ssize);
622 if (hidx & _PTEIDX_SECONDARY)
623 hash = ~hash;
624
625 slot = (hash & htab_hash_mask) * HPTES_PER_GROUP;
626 slot += hidx & _PTEIDX_GROUP_IX;
627
628 hptep = htab_address + slot;
629 want_v = hpte_encode_avpn(vpn, psize, ssize);
630 hpte_v = hpte_get_old_v(hptep);
631
632 /* Even if we miss, we need to invalidate the TLB */
633 if (HPTE_V_COMPARE(hpte_v, want_v) && (hpte_v & HPTE_V_VALID)) {
634 /* recheck with locks held */
635 native_lock_hpte(hptep);
636 hpte_v = hpte_get_old_v(hptep);
637
638 if (HPTE_V_COMPARE(hpte_v, want_v) && (hpte_v & HPTE_V_VALID)) {
639 /* Invalidate the hpte. NOTE: this also unlocks it */
640 release_hpte_lock();
641 hptep->v = 0;
642 } else
643 native_unlock_hpte(hptep);
644 }
645 /*
646 * We need to do tlb invalidate for all the address, tlbie
647 * instruction compares entry_VA in tlb with the VA specified
648 * here
649 */
650 tlbie(vpn, psize, apsize: actual_psize, ssize, local);
651 }
652 local_irq_restore(flags);
653}
654#else
655static void native_hugepage_invalidate(unsigned long vsid,
656 unsigned long addr,
657 unsigned char *hpte_slot_array,
658 int psize, int ssize, int local)
659{
660 WARN(1, "%s called without THP support\n", __func__);
661}
662#endif
663
664static void hpte_decode(struct hash_pte *hpte, unsigned long slot,
665 int *psize, int *apsize, int *ssize, unsigned long *vpn)
666{
667 unsigned long avpn, pteg, vpi;
668 unsigned long hpte_v = be64_to_cpu(hpte->v);
669 unsigned long hpte_r = be64_to_cpu(hpte->r);
670 unsigned long vsid, seg_off;
671 int size, a_size, shift;
672 /* Look at the 8 bit LP value */
673 unsigned int lp = (hpte_r >> LP_SHIFT) & ((1 << LP_BITS) - 1);
674
675 if (cpu_has_feature(CPU_FTR_ARCH_300)) {
676 hpte_v = hpte_new_to_old_v(hpte_v, hpte_r);
677 hpte_r = hpte_new_to_old_r(hpte_r);
678 }
679 if (!(hpte_v & HPTE_V_LARGE)) {
680 size = MMU_PAGE_4K;
681 a_size = MMU_PAGE_4K;
682 } else {
683 size = hpte_page_sizes[lp] & 0xf;
684 a_size = hpte_page_sizes[lp] >> 4;
685 }
686 /* This works for all page sizes, and for 256M and 1T segments */
687 *ssize = hpte_v >> HPTE_V_SSIZE_SHIFT;
688 shift = mmu_psize_defs[size].shift;
689
690 avpn = (HPTE_V_AVPN_VAL(hpte_v) & ~mmu_psize_defs[size].avpnm);
691 pteg = slot / HPTES_PER_GROUP;
692 if (hpte_v & HPTE_V_SECONDARY)
693 pteg = ~pteg;
694
695 switch (*ssize) {
696 case MMU_SEGSIZE_256M:
697 /* We only have 28 - 23 bits of seg_off in avpn */
698 seg_off = (avpn & 0x1f) << 23;
699 vsid = avpn >> 5;
700 /* We can find more bits from the pteg value */
701 if (shift < 23) {
702 vpi = (vsid ^ pteg) & htab_hash_mask;
703 seg_off |= vpi << shift;
704 }
705 *vpn = vsid << (SID_SHIFT - VPN_SHIFT) | seg_off >> VPN_SHIFT;
706 break;
707 case MMU_SEGSIZE_1T:
708 /* We only have 40 - 23 bits of seg_off in avpn */
709 seg_off = (avpn & 0x1ffff) << 23;
710 vsid = avpn >> 17;
711 if (shift < 23) {
712 vpi = (vsid ^ (vsid << 25) ^ pteg) & htab_hash_mask;
713 seg_off |= vpi << shift;
714 }
715 *vpn = vsid << (SID_SHIFT_1T - VPN_SHIFT) | seg_off >> VPN_SHIFT;
716 break;
717 default:
718 *vpn = size = 0;
719 }
720 *psize = size;
721 *apsize = a_size;
722}
723
724/*
725 * clear all mappings on kexec. All cpus are in real mode (or they will
726 * be when they isi), and we are the only one left. We rely on our kernel
727 * mapping being 0xC0's and the hardware ignoring those two real bits.
728 *
729 * This must be called with interrupts disabled.
730 *
731 * Taking the native_tlbie_lock is unsafe here due to the possibility of
732 * lockdep being on. On pre POWER5 hardware, not taking the lock could
733 * cause deadlock. POWER5 and newer not taking the lock is fine. This only
734 * gets called during boot before secondary CPUs have come up and during
735 * crashdump and all bets are off anyway.
736 *
737 * TODO: add batching support when enabled. remember, no dynamic memory here,
738 * although there is the control page available...
739 */
740static notrace void native_hpte_clear(void)
741{
742 unsigned long vpn = 0;
743 unsigned long slot, slots;
744 struct hash_pte *hptep = htab_address;
745 unsigned long hpte_v;
746 unsigned long pteg_count;
747 int psize, apsize, ssize;
748
749 pteg_count = htab_hash_mask + 1;
750
751 slots = pteg_count * HPTES_PER_GROUP;
752
753 for (slot = 0; slot < slots; slot++, hptep++) {
754 /*
755 * we could lock the pte here, but we are the only cpu
756 * running, right? and for crash dump, we probably
757 * don't want to wait for a maybe bad cpu.
758 */
759 hpte_v = be64_to_cpu(hptep->v);
760
761 /*
762 * Call __tlbie() here rather than tlbie() since we can't take the
763 * native_tlbie_lock.
764 */
765 if (hpte_v & HPTE_V_VALID) {
766 hpte_decode(hpte: hptep, slot, psize: &psize, apsize: &apsize, ssize: &ssize, vpn: &vpn);
767 hptep->v = 0;
768 ___tlbie(vpn, psize, apsize, ssize);
769 }
770 }
771
772 asm volatile("eieio; tlbsync; ptesync":::"memory");
773}
774
775/*
776 * Batched hash table flush, we batch the tlbie's to avoid taking/releasing
777 * the lock all the time
778 */
779static void native_flush_hash_range(unsigned long number, int local)
780{
781 unsigned long vpn = 0;
782 unsigned long hash, index, hidx, shift, slot;
783 struct hash_pte *hptep;
784 unsigned long hpte_v;
785 unsigned long want_v;
786 unsigned long flags;
787 real_pte_t pte;
788 struct ppc64_tlb_batch *batch = this_cpu_ptr(&ppc64_tlb_batch);
789 unsigned long psize = batch->psize;
790 int ssize = batch->ssize;
791 int i;
792 unsigned int use_local;
793
794 use_local = local && mmu_has_feature(MMU_FTR_TLBIEL) &&
795 mmu_psize_defs[psize].tlbiel && !cxl_ctx_in_use();
796
797 local_irq_save(flags);
798
799 for (i = 0; i < number; i++) {
800 vpn = batch->vpn[i];
801 pte = batch->pte[i];
802
803 pte_iterate_hashed_subpages(pte, psize, vpn, index, shift) {
804 hash = hpt_hash(vpn, shift, ssize);
805 hidx = __rpte_to_hidx(pte, index);
806 if (hidx & _PTEIDX_SECONDARY)
807 hash = ~hash;
808 slot = (hash & htab_hash_mask) * HPTES_PER_GROUP;
809 slot += hidx & _PTEIDX_GROUP_IX;
810 hptep = htab_address + slot;
811 want_v = hpte_encode_avpn(vpn, psize, ssize);
812 hpte_v = hpte_get_old_v(hptep);
813
814 if (!HPTE_V_COMPARE(hpte_v, want_v) || !(hpte_v & HPTE_V_VALID))
815 continue;
816 /* lock and try again */
817 native_lock_hpte(hptep);
818 hpte_v = hpte_get_old_v(hptep);
819
820 if (!HPTE_V_COMPARE(hpte_v, want_v) || !(hpte_v & HPTE_V_VALID))
821 native_unlock_hpte(hptep);
822 else {
823 release_hpte_lock();
824 hptep->v = 0;
825 }
826
827 } pte_iterate_hashed_end();
828 }
829
830 if (use_local) {
831 asm volatile("ptesync":::"memory");
832 for (i = 0; i < number; i++) {
833 vpn = batch->vpn[i];
834 pte = batch->pte[i];
835
836 pte_iterate_hashed_subpages(pte, psize,
837 vpn, index, shift) {
838 __tlbiel(vpn, psize, psize, ssize);
839 } pte_iterate_hashed_end();
840 }
841 ppc_after_tlbiel_barrier();
842 } else {
843 int lock_tlbie = !mmu_has_feature(MMU_FTR_LOCKLESS_TLBIE);
844
845 if (lock_tlbie)
846 raw_spin_lock(&native_tlbie_lock);
847
848 asm volatile("ptesync":::"memory");
849 for (i = 0; i < number; i++) {
850 vpn = batch->vpn[i];
851 pte = batch->pte[i];
852
853 pte_iterate_hashed_subpages(pte, psize,
854 vpn, index, shift) {
855 __tlbie(vpn, psize, psize, ssize);
856 } pte_iterate_hashed_end();
857 }
858 /*
859 * Just do one more with the last used values.
860 */
861 fixup_tlbie_vpn(vpn, psize, apsize: psize, ssize);
862 asm volatile("eieio; tlbsync; ptesync":::"memory");
863
864 if (lock_tlbie)
865 raw_spin_unlock(&native_tlbie_lock);
866 }
867
868 local_irq_restore(flags);
869}
870
871void __init hpte_init_native(void)
872{
873 mmu_hash_ops.hpte_invalidate = native_hpte_invalidate;
874 mmu_hash_ops.hpte_updatepp = native_hpte_updatepp;
875 mmu_hash_ops.hpte_updateboltedpp = native_hpte_updateboltedpp;
876 mmu_hash_ops.hpte_removebolted = native_hpte_removebolted;
877 mmu_hash_ops.hpte_insert = native_hpte_insert;
878 mmu_hash_ops.hpte_remove = native_hpte_remove;
879 mmu_hash_ops.hpte_clear_all = native_hpte_clear;
880 mmu_hash_ops.flush_hash_range = native_flush_hash_range;
881 mmu_hash_ops.hugepage_invalidate = native_hugepage_invalidate;
882}
883

source code of linux/arch/powerpc/mm/book3s64/hash_native.c