1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *
4  * Copyright 2010-2011 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com>
5  */
6 
7 #include <linux/types.h>
8 #include <linux/string.h>
9 #include <linux/kvm.h>
10 #include <linux/kvm_host.h>
11 #include <linux/hugetlb.h>
12 #include <linux/module.h>
13 #include <linux/log2.h>
14 #include <linux/sizes.h>
15 
16 #include <asm/trace.h>
17 #include <asm/kvm_ppc.h>
18 #include <asm/kvm_book3s.h>
19 #include <asm/book3s/64/mmu-hash.h>
20 #include <asm/hvcall.h>
21 #include <asm/synch.h>
22 #include <asm/ppc-opcode.h>
23 #include <asm/pte-walk.h>
24 
25 /* Translate address of a vmalloc'd thing to a linear map address */
26 static void *real_vmalloc_addr(void *addr)
27 {
28 	return __va(ppc_find_vmap_phys((unsigned long)addr));
29 }
30 
31 /* Return 1 if we need to do a global tlbie, 0 if we can use tlbiel */
32 static int global_invalidates(struct kvm *kvm)
33 {
34 	int global;
35 	int cpu;
36 
37 	/*
38 	 * If there is only one vcore, and it's currently running,
39 	 * as indicated by local_paca->kvm_hstate.kvm_vcpu being set,
40 	 * we can use tlbiel as long as we mark all other physical
41 	 * cores as potentially having stale TLB entries for this lpid.
42 	 * Otherwise, don't use tlbiel.
43 	 */
44 	if (kvm->arch.online_vcores == 1 && local_paca->kvm_hstate.kvm_vcpu)
45 		global = 0;
46 	else
47 		global = 1;
48 
49 	/* LPID has been switched to host if in virt mode so can't do local */
50 	if (!global && (mfmsr() & (MSR_IR|MSR_DR)))
51 		global = 1;
52 
53 	if (!global) {
54 		/* any other core might now have stale TLB entries... */
55 		smp_wmb();
56 		cpumask_setall(&kvm->arch.need_tlb_flush);
57 		cpu = local_paca->kvm_hstate.kvm_vcore->pcpu;
58 		/*
59 		 * On POWER9, threads are independent but the TLB is shared,
60 		 * so use the bit for the first thread to represent the core.
61 		 */
62 		if (cpu_has_feature(CPU_FTR_ARCH_300))
63 			cpu = cpu_first_tlb_thread_sibling(cpu);
64 		cpumask_clear_cpu(cpu, &kvm->arch.need_tlb_flush);
65 	}
66 
67 	return global;
68 }
69 
70 /*
71  * Add this HPTE into the chain for the real page.
72  * Must be called with the chain locked; it unlocks the chain.
73  */
74 void kvmppc_add_revmap_chain(struct kvm *kvm, struct revmap_entry *rev,
75 			     unsigned long *rmap, long pte_index, int realmode)
76 {
77 	struct revmap_entry *head, *tail;
78 	unsigned long i;
79 
80 	if (*rmap & KVMPPC_RMAP_PRESENT) {
81 		i = *rmap & KVMPPC_RMAP_INDEX;
82 		head = &kvm->arch.hpt.rev[i];
83 		if (realmode)
84 			head = real_vmalloc_addr(head);
85 		tail = &kvm->arch.hpt.rev[head->back];
86 		if (realmode)
87 			tail = real_vmalloc_addr(tail);
88 		rev->forw = i;
89 		rev->back = head->back;
90 		tail->forw = pte_index;
91 		head->back = pte_index;
92 	} else {
93 		rev->forw = rev->back = pte_index;
94 		*rmap = (*rmap & ~KVMPPC_RMAP_INDEX) |
95 			pte_index | KVMPPC_RMAP_PRESENT | KVMPPC_RMAP_HPT;
96 	}
97 	unlock_rmap(rmap);
98 }
99 EXPORT_SYMBOL_GPL(kvmppc_add_revmap_chain);
100 
101 /* Update the dirty bitmap of a memslot */
102 void kvmppc_update_dirty_map(const struct kvm_memory_slot *memslot,
103 			     unsigned long gfn, unsigned long psize)
104 {
105 	unsigned long npages;
106 
107 	if (!psize || !memslot->dirty_bitmap)
108 		return;
109 	npages = (psize + PAGE_SIZE - 1) / PAGE_SIZE;
110 	gfn -= memslot->base_gfn;
111 	set_dirty_bits_atomic(memslot->dirty_bitmap, gfn, npages);
112 }
113 EXPORT_SYMBOL_GPL(kvmppc_update_dirty_map);
114 
115 static void kvmppc_set_dirty_from_hpte(struct kvm *kvm,
116 				unsigned long hpte_v, unsigned long hpte_gr)
117 {
118 	struct kvm_memory_slot *memslot;
119 	unsigned long gfn;
120 	unsigned long psize;
121 
122 	psize = kvmppc_actual_pgsz(hpte_v, hpte_gr);
123 	gfn = hpte_rpn(hpte_gr, psize);
124 	memslot = __gfn_to_memslot(kvm_memslots_raw(kvm), gfn);
125 	if (memslot && memslot->dirty_bitmap)
126 		kvmppc_update_dirty_map(memslot, gfn, psize);
127 }
128 
129 /* Returns a pointer to the revmap entry for the page mapped by a HPTE */
130 static unsigned long *revmap_for_hpte(struct kvm *kvm, unsigned long hpte_v,
131 				      unsigned long hpte_gr,
132 				      struct kvm_memory_slot **memslotp,
133 				      unsigned long *gfnp)
134 {
135 	struct kvm_memory_slot *memslot;
136 	unsigned long *rmap;
137 	unsigned long gfn;
138 
139 	gfn = hpte_rpn(hpte_gr, kvmppc_actual_pgsz(hpte_v, hpte_gr));
140 	memslot = __gfn_to_memslot(kvm_memslots_raw(kvm), gfn);
141 	if (memslotp)
142 		*memslotp = memslot;
143 	if (gfnp)
144 		*gfnp = gfn;
145 	if (!memslot)
146 		return NULL;
147 
148 	rmap = real_vmalloc_addr(&memslot->arch.rmap[gfn - memslot->base_gfn]);
149 	return rmap;
150 }
151 
152 /* Remove this HPTE from the chain for a real page */
153 static void remove_revmap_chain(struct kvm *kvm, long pte_index,
154 				struct revmap_entry *rev,
155 				unsigned long hpte_v, unsigned long hpte_r)
156 {
157 	struct revmap_entry *next, *prev;
158 	unsigned long ptel, head;
159 	unsigned long *rmap;
160 	unsigned long rcbits;
161 	struct kvm_memory_slot *memslot;
162 	unsigned long gfn;
163 
164 	rcbits = hpte_r & (HPTE_R_R | HPTE_R_C);
165 	ptel = rev->guest_rpte |= rcbits;
166 	rmap = revmap_for_hpte(kvm, hpte_v, ptel, &memslot, &gfn);
167 	if (!rmap)
168 		return;
169 	lock_rmap(rmap);
170 
171 	head = *rmap & KVMPPC_RMAP_INDEX;
172 	next = real_vmalloc_addr(&kvm->arch.hpt.rev[rev->forw]);
173 	prev = real_vmalloc_addr(&kvm->arch.hpt.rev[rev->back]);
174 	next->back = rev->back;
175 	prev->forw = rev->forw;
176 	if (head == pte_index) {
177 		head = rev->forw;
178 		if (head == pte_index)
179 			*rmap &= ~(KVMPPC_RMAP_PRESENT | KVMPPC_RMAP_INDEX);
180 		else
181 			*rmap = (*rmap & ~KVMPPC_RMAP_INDEX) | head;
182 	}
183 	*rmap |= rcbits << KVMPPC_RMAP_RC_SHIFT;
184 	if (rcbits & HPTE_R_C)
185 		kvmppc_update_dirty_map(memslot, gfn,
186 					kvmppc_actual_pgsz(hpte_v, hpte_r));
187 	unlock_rmap(rmap);
188 }
189 
190 long kvmppc_do_h_enter(struct kvm *kvm, unsigned long flags,
191 		       long pte_index, unsigned long pteh, unsigned long ptel,
192 		       pgd_t *pgdir, bool realmode, unsigned long *pte_idx_ret)
193 {
194 	unsigned long i, pa, gpa, gfn, psize;
195 	unsigned long slot_fn, hva;
196 	__be64 *hpte;
197 	struct revmap_entry *rev;
198 	unsigned long g_ptel;
199 	struct kvm_memory_slot *memslot;
200 	unsigned hpage_shift;
201 	bool is_ci;
202 	unsigned long *rmap;
203 	pte_t *ptep;
204 	unsigned int writing;
205 	unsigned long mmu_seq;
206 	unsigned long rcbits;
207 
208 	if (kvm_is_radix(kvm))
209 		return H_FUNCTION;
210 	psize = kvmppc_actual_pgsz(pteh, ptel);
211 	if (!psize)
212 		return H_PARAMETER;
213 	writing = hpte_is_writable(ptel);
214 	pteh &= ~(HPTE_V_HVLOCK | HPTE_V_ABSENT | HPTE_V_VALID);
215 	ptel &= ~HPTE_GR_RESERVED;
216 	g_ptel = ptel;
217 
218 	/* used later to detect if we might have been invalidated */
219 	mmu_seq = kvm->mmu_notifier_seq;
220 	smp_rmb();
221 
222 	/* Find the memslot (if any) for this address */
223 	gpa = (ptel & HPTE_R_RPN) & ~(psize - 1);
224 	gfn = gpa >> PAGE_SHIFT;
225 	memslot = __gfn_to_memslot(kvm_memslots_raw(kvm), gfn);
226 	pa = 0;
227 	is_ci = false;
228 	rmap = NULL;
229 	if (!(memslot && !(memslot->flags & KVM_MEMSLOT_INVALID))) {
230 		/* Emulated MMIO - mark this with key=31 */
231 		pteh |= HPTE_V_ABSENT;
232 		ptel |= HPTE_R_KEY_HI | HPTE_R_KEY_LO;
233 		goto do_insert;
234 	}
235 
236 	/* Check if the requested page fits entirely in the memslot. */
237 	if (!slot_is_aligned(memslot, psize))
238 		return H_PARAMETER;
239 	slot_fn = gfn - memslot->base_gfn;
240 	rmap = &memslot->arch.rmap[slot_fn];
241 
242 	/* Translate to host virtual address */
243 	hva = __gfn_to_hva_memslot(memslot, gfn);
244 
245 	arch_spin_lock(&kvm->mmu_lock.rlock.raw_lock);
246 	ptep = find_kvm_host_pte(kvm, mmu_seq, hva, &hpage_shift);
247 	if (ptep) {
248 		pte_t pte;
249 		unsigned int host_pte_size;
250 
251 		if (hpage_shift)
252 			host_pte_size = 1ul << hpage_shift;
253 		else
254 			host_pte_size = PAGE_SIZE;
255 		/*
256 		 * We should always find the guest page size
257 		 * to <= host page size, if host is using hugepage
258 		 */
259 		if (host_pte_size < psize) {
260 			arch_spin_unlock(&kvm->mmu_lock.rlock.raw_lock);
261 			return H_PARAMETER;
262 		}
263 		pte = kvmppc_read_update_linux_pte(ptep, writing);
264 		if (pte_present(pte) && !pte_protnone(pte)) {
265 			if (writing && !__pte_write(pte))
266 				/* make the actual HPTE be read-only */
267 				ptel = hpte_make_readonly(ptel);
268 			is_ci = pte_ci(pte);
269 			pa = pte_pfn(pte) << PAGE_SHIFT;
270 			pa |= hva & (host_pte_size - 1);
271 			pa |= gpa & ~PAGE_MASK;
272 		}
273 	}
274 	arch_spin_unlock(&kvm->mmu_lock.rlock.raw_lock);
275 
276 	ptel &= HPTE_R_KEY | HPTE_R_PP0 | (psize-1);
277 	ptel |= pa;
278 
279 	if (pa)
280 		pteh |= HPTE_V_VALID;
281 	else {
282 		pteh |= HPTE_V_ABSENT;
283 		ptel &= ~(HPTE_R_KEY_HI | HPTE_R_KEY_LO);
284 	}
285 
286 	/*If we had host pte mapping then  Check WIMG */
287 	if (ptep && !hpte_cache_flags_ok(ptel, is_ci)) {
288 		if (is_ci)
289 			return H_PARAMETER;
290 		/*
291 		 * Allow guest to map emulated device memory as
292 		 * uncacheable, but actually make it cacheable.
293 		 */
294 		ptel &= ~(HPTE_R_W|HPTE_R_I|HPTE_R_G);
295 		ptel |= HPTE_R_M;
296 	}
297 
298 	/* Find and lock the HPTEG slot to use */
299  do_insert:
300 	if (pte_index >= kvmppc_hpt_npte(&kvm->arch.hpt))
301 		return H_PARAMETER;
302 	if (likely((flags & H_EXACT) == 0)) {
303 		pte_index &= ~7UL;
304 		hpte = (__be64 *)(kvm->arch.hpt.virt + (pte_index << 4));
305 		for (i = 0; i < 8; ++i) {
306 			if ((be64_to_cpu(*hpte) & HPTE_V_VALID) == 0 &&
307 			    try_lock_hpte(hpte, HPTE_V_HVLOCK | HPTE_V_VALID |
308 					  HPTE_V_ABSENT))
309 				break;
310 			hpte += 2;
311 		}
312 		if (i == 8) {
313 			/*
314 			 * Since try_lock_hpte doesn't retry (not even stdcx.
315 			 * failures), it could be that there is a free slot
316 			 * but we transiently failed to lock it.  Try again,
317 			 * actually locking each slot and checking it.
318 			 */
319 			hpte -= 16;
320 			for (i = 0; i < 8; ++i) {
321 				u64 pte;
322 				while (!try_lock_hpte(hpte, HPTE_V_HVLOCK))
323 					cpu_relax();
324 				pte = be64_to_cpu(hpte[0]);
325 				if (!(pte & (HPTE_V_VALID | HPTE_V_ABSENT)))
326 					break;
327 				__unlock_hpte(hpte, pte);
328 				hpte += 2;
329 			}
330 			if (i == 8)
331 				return H_PTEG_FULL;
332 		}
333 		pte_index += i;
334 	} else {
335 		hpte = (__be64 *)(kvm->arch.hpt.virt + (pte_index << 4));
336 		if (!try_lock_hpte(hpte, HPTE_V_HVLOCK | HPTE_V_VALID |
337 				   HPTE_V_ABSENT)) {
338 			/* Lock the slot and check again */
339 			u64 pte;
340 
341 			while (!try_lock_hpte(hpte, HPTE_V_HVLOCK))
342 				cpu_relax();
343 			pte = be64_to_cpu(hpte[0]);
344 			if (pte & (HPTE_V_VALID | HPTE_V_ABSENT)) {
345 				__unlock_hpte(hpte, pte);
346 				return H_PTEG_FULL;
347 			}
348 		}
349 	}
350 
351 	/* Save away the guest's idea of the second HPTE dword */
352 	rev = &kvm->arch.hpt.rev[pte_index];
353 	if (realmode)
354 		rev = real_vmalloc_addr(rev);
355 	if (rev) {
356 		rev->guest_rpte = g_ptel;
357 		note_hpte_modification(kvm, rev);
358 	}
359 
360 	/* Link HPTE into reverse-map chain */
361 	if (pteh & HPTE_V_VALID) {
362 		if (realmode)
363 			rmap = real_vmalloc_addr(rmap);
364 		lock_rmap(rmap);
365 		/* Check for pending invalidations under the rmap chain lock */
366 		if (mmu_notifier_retry(kvm, mmu_seq)) {
367 			/* inval in progress, write a non-present HPTE */
368 			pteh |= HPTE_V_ABSENT;
369 			pteh &= ~HPTE_V_VALID;
370 			ptel &= ~(HPTE_R_KEY_HI | HPTE_R_KEY_LO);
371 			unlock_rmap(rmap);
372 		} else {
373 			kvmppc_add_revmap_chain(kvm, rev, rmap, pte_index,
374 						realmode);
375 			/* Only set R/C in real HPTE if already set in *rmap */
376 			rcbits = *rmap >> KVMPPC_RMAP_RC_SHIFT;
377 			ptel &= rcbits | ~(HPTE_R_R | HPTE_R_C);
378 		}
379 	}
380 
381 	/* Convert to new format on P9 */
382 	if (cpu_has_feature(CPU_FTR_ARCH_300)) {
383 		ptel = hpte_old_to_new_r(pteh, ptel);
384 		pteh = hpte_old_to_new_v(pteh);
385 	}
386 	hpte[1] = cpu_to_be64(ptel);
387 
388 	/* Write the first HPTE dword, unlocking the HPTE and making it valid */
389 	eieio();
390 	__unlock_hpte(hpte, pteh);
391 	asm volatile("ptesync" : : : "memory");
392 
393 	*pte_idx_ret = pte_index;
394 	return H_SUCCESS;
395 }
396 EXPORT_SYMBOL_GPL(kvmppc_do_h_enter);
397 
398 long kvmppc_h_enter(struct kvm_vcpu *vcpu, unsigned long flags,
399 		    long pte_index, unsigned long pteh, unsigned long ptel)
400 {
401 	return kvmppc_do_h_enter(vcpu->kvm, flags, pte_index, pteh, ptel,
402 				 vcpu->arch.pgdir, true,
403 				 &vcpu->arch.regs.gpr[4]);
404 }
405 EXPORT_SYMBOL_GPL(kvmppc_h_enter);
406 
407 #ifdef __BIG_ENDIAN__
408 #define LOCK_TOKEN	(*(u32 *)(&get_paca()->lock_token))
409 #else
410 #define LOCK_TOKEN	(*(u32 *)(&get_paca()->paca_index))
411 #endif
412 
413 static inline int is_mmio_hpte(unsigned long v, unsigned long r)
414 {
415 	return ((v & HPTE_V_ABSENT) &&
416 		(r & (HPTE_R_KEY_HI | HPTE_R_KEY_LO)) ==
417 		(HPTE_R_KEY_HI | HPTE_R_KEY_LO));
418 }
419 
420 static inline void fixup_tlbie_lpid(unsigned long rb_value, unsigned long lpid)
421 {
422 
423 	if (cpu_has_feature(CPU_FTR_P9_TLBIE_ERAT_BUG)) {
424 		/* Radix flush for a hash guest */
425 
426 		unsigned long rb,rs,prs,r,ric;
427 
428 		rb = PPC_BIT(52); /* IS = 2 */
429 		rs = 0;  /* lpid = 0 */
430 		prs = 0; /* partition scoped */
431 		r = 1;   /* radix format */
432 		ric = 0; /* RIC_FLSUH_TLB */
433 
434 		/*
435 		 * Need the extra ptesync to make sure we don't
436 		 * re-order the tlbie
437 		 */
438 		asm volatile("ptesync": : :"memory");
439 		asm volatile(PPC_TLBIE_5(%0, %4, %3, %2, %1)
440 			     : : "r"(rb), "i"(r), "i"(prs),
441 			       "i"(ric), "r"(rs) : "memory");
442 	}
443 
444 	if (cpu_has_feature(CPU_FTR_P9_TLBIE_STQ_BUG)) {
445 		asm volatile("ptesync": : :"memory");
446 		asm volatile(PPC_TLBIE_5(%0,%1,0,0,0) : :
447 			     "r" (rb_value), "r" (lpid));
448 	}
449 }
450 
451 static void do_tlbies(struct kvm *kvm, unsigned long *rbvalues,
452 		      long npages, int global, bool need_sync)
453 {
454 	long i;
455 
456 	/*
457 	 * We use the POWER9 5-operand versions of tlbie and tlbiel here.
458 	 * Since we are using RIC=0 PRS=0 R=0, and P7/P8 tlbiel ignores
459 	 * the RS field, this is backwards-compatible with P7 and P8.
460 	 */
461 	if (global) {
462 		if (need_sync)
463 			asm volatile("ptesync" : : : "memory");
464 		for (i = 0; i < npages; ++i) {
465 			asm volatile(PPC_TLBIE_5(%0,%1,0,0,0) : :
466 				     "r" (rbvalues[i]), "r" (kvm->arch.lpid));
467 		}
468 
469 		fixup_tlbie_lpid(rbvalues[i - 1], kvm->arch.lpid);
470 		asm volatile("eieio; tlbsync; ptesync" : : : "memory");
471 	} else {
472 		if (need_sync)
473 			asm volatile("ptesync" : : : "memory");
474 		for (i = 0; i < npages; ++i) {
475 			asm volatile(PPC_TLBIEL(%0,%1,0,0,0) : :
476 				     "r" (rbvalues[i]), "r" (0));
477 		}
478 		asm volatile("ptesync" : : : "memory");
479 	}
480 }
481 
482 long kvmppc_do_h_remove(struct kvm *kvm, unsigned long flags,
483 			unsigned long pte_index, unsigned long avpn,
484 			unsigned long *hpret)
485 {
486 	__be64 *hpte;
487 	unsigned long v, r, rb;
488 	struct revmap_entry *rev;
489 	u64 pte, orig_pte, pte_r;
490 
491 	if (kvm_is_radix(kvm))
492 		return H_FUNCTION;
493 	if (pte_index >= kvmppc_hpt_npte(&kvm->arch.hpt))
494 		return H_PARAMETER;
495 	hpte = (__be64 *)(kvm->arch.hpt.virt + (pte_index << 4));
496 	while (!try_lock_hpte(hpte, HPTE_V_HVLOCK))
497 		cpu_relax();
498 	pte = orig_pte = be64_to_cpu(hpte[0]);
499 	pte_r = be64_to_cpu(hpte[1]);
500 	if (cpu_has_feature(CPU_FTR_ARCH_300)) {
501 		pte = hpte_new_to_old_v(pte, pte_r);
502 		pte_r = hpte_new_to_old_r(pte_r);
503 	}
504 	if ((pte & (HPTE_V_ABSENT | HPTE_V_VALID)) == 0 ||
505 	    ((flags & H_AVPN) && (pte & ~0x7fUL) != avpn) ||
506 	    ((flags & H_ANDCOND) && (pte & avpn) != 0)) {
507 		__unlock_hpte(hpte, orig_pte);
508 		return H_NOT_FOUND;
509 	}
510 
511 	rev = real_vmalloc_addr(&kvm->arch.hpt.rev[pte_index]);
512 	v = pte & ~HPTE_V_HVLOCK;
513 	if (v & HPTE_V_VALID) {
514 		hpte[0] &= ~cpu_to_be64(HPTE_V_VALID);
515 		rb = compute_tlbie_rb(v, pte_r, pte_index);
516 		do_tlbies(kvm, &rb, 1, global_invalidates(kvm), true);
517 		/*
518 		 * The reference (R) and change (C) bits in a HPT
519 		 * entry can be set by hardware at any time up until
520 		 * the HPTE is invalidated and the TLB invalidation
521 		 * sequence has completed.  This means that when
522 		 * removing a HPTE, we need to re-read the HPTE after
523 		 * the invalidation sequence has completed in order to
524 		 * obtain reliable values of R and C.
525 		 */
526 		remove_revmap_chain(kvm, pte_index, rev, v,
527 				    be64_to_cpu(hpte[1]));
528 	}
529 	r = rev->guest_rpte & ~HPTE_GR_RESERVED;
530 	note_hpte_modification(kvm, rev);
531 	unlock_hpte(hpte, 0);
532 
533 	if (is_mmio_hpte(v, pte_r))
534 		atomic64_inc(&kvm->arch.mmio_update);
535 
536 	if (v & HPTE_V_ABSENT)
537 		v = (v & ~HPTE_V_ABSENT) | HPTE_V_VALID;
538 	hpret[0] = v;
539 	hpret[1] = r;
540 	return H_SUCCESS;
541 }
542 EXPORT_SYMBOL_GPL(kvmppc_do_h_remove);
543 
544 long kvmppc_h_remove(struct kvm_vcpu *vcpu, unsigned long flags,
545 		     unsigned long pte_index, unsigned long avpn)
546 {
547 	return kvmppc_do_h_remove(vcpu->kvm, flags, pte_index, avpn,
548 				  &vcpu->arch.regs.gpr[4]);
549 }
550 EXPORT_SYMBOL_GPL(kvmppc_h_remove);
551 
552 long kvmppc_h_bulk_remove(struct kvm_vcpu *vcpu)
553 {
554 	struct kvm *kvm = vcpu->kvm;
555 	unsigned long *args = &vcpu->arch.regs.gpr[4];
556 	__be64 *hp, *hptes[4];
557 	unsigned long tlbrb[4];
558 	long int i, j, k, n, found, indexes[4];
559 	unsigned long flags, req, pte_index, rcbits;
560 	int global;
561 	long int ret = H_SUCCESS;
562 	struct revmap_entry *rev, *revs[4];
563 	u64 hp0, hp1;
564 
565 	if (kvm_is_radix(kvm))
566 		return H_FUNCTION;
567 	global = global_invalidates(kvm);
568 	for (i = 0; i < 4 && ret == H_SUCCESS; ) {
569 		n = 0;
570 		for (; i < 4; ++i) {
571 			j = i * 2;
572 			pte_index = args[j];
573 			flags = pte_index >> 56;
574 			pte_index &= ((1ul << 56) - 1);
575 			req = flags >> 6;
576 			flags &= 3;
577 			if (req == 3) {		/* no more requests */
578 				i = 4;
579 				break;
580 			}
581 			if (req != 1 || flags == 3 ||
582 			    pte_index >= kvmppc_hpt_npte(&kvm->arch.hpt)) {
583 				/* parameter error */
584 				args[j] = ((0xa0 | flags) << 56) + pte_index;
585 				ret = H_PARAMETER;
586 				break;
587 			}
588 			hp = (__be64 *) (kvm->arch.hpt.virt + (pte_index << 4));
589 			/* to avoid deadlock, don't spin except for first */
590 			if (!try_lock_hpte(hp, HPTE_V_HVLOCK)) {
591 				if (n)
592 					break;
593 				while (!try_lock_hpte(hp, HPTE_V_HVLOCK))
594 					cpu_relax();
595 			}
596 			found = 0;
597 			hp0 = be64_to_cpu(hp[0]);
598 			hp1 = be64_to_cpu(hp[1]);
599 			if (cpu_has_feature(CPU_FTR_ARCH_300)) {
600 				hp0 = hpte_new_to_old_v(hp0, hp1);
601 				hp1 = hpte_new_to_old_r(hp1);
602 			}
603 			if (hp0 & (HPTE_V_ABSENT | HPTE_V_VALID)) {
604 				switch (flags & 3) {
605 				case 0:		/* absolute */
606 					found = 1;
607 					break;
608 				case 1:		/* andcond */
609 					if (!(hp0 & args[j + 1]))
610 						found = 1;
611 					break;
612 				case 2:		/* AVPN */
613 					if ((hp0 & ~0x7fUL) == args[j + 1])
614 						found = 1;
615 					break;
616 				}
617 			}
618 			if (!found) {
619 				hp[0] &= ~cpu_to_be64(HPTE_V_HVLOCK);
620 				args[j] = ((0x90 | flags) << 56) + pte_index;
621 				continue;
622 			}
623 
624 			args[j] = ((0x80 | flags) << 56) + pte_index;
625 			rev = real_vmalloc_addr(&kvm->arch.hpt.rev[pte_index]);
626 			note_hpte_modification(kvm, rev);
627 
628 			if (!(hp0 & HPTE_V_VALID)) {
629 				/* insert R and C bits from PTE */
630 				rcbits = rev->guest_rpte & (HPTE_R_R|HPTE_R_C);
631 				args[j] |= rcbits << (56 - 5);
632 				hp[0] = 0;
633 				if (is_mmio_hpte(hp0, hp1))
634 					atomic64_inc(&kvm->arch.mmio_update);
635 				continue;
636 			}
637 
638 			/* leave it locked */
639 			hp[0] &= ~cpu_to_be64(HPTE_V_VALID);
640 			tlbrb[n] = compute_tlbie_rb(hp0, hp1, pte_index);
641 			indexes[n] = j;
642 			hptes[n] = hp;
643 			revs[n] = rev;
644 			++n;
645 		}
646 
647 		if (!n)
648 			break;
649 
650 		/* Now that we've collected a batch, do the tlbies */
651 		do_tlbies(kvm, tlbrb, n, global, true);
652 
653 		/* Read PTE low words after tlbie to get final R/C values */
654 		for (k = 0; k < n; ++k) {
655 			j = indexes[k];
656 			pte_index = args[j] & ((1ul << 56) - 1);
657 			hp = hptes[k];
658 			rev = revs[k];
659 			remove_revmap_chain(kvm, pte_index, rev,
660 				be64_to_cpu(hp[0]), be64_to_cpu(hp[1]));
661 			rcbits = rev->guest_rpte & (HPTE_R_R|HPTE_R_C);
662 			args[j] |= rcbits << (56 - 5);
663 			__unlock_hpte(hp, 0);
664 		}
665 	}
666 
667 	return ret;
668 }
669 EXPORT_SYMBOL_GPL(kvmppc_h_bulk_remove);
670 
671 long kvmppc_h_protect(struct kvm_vcpu *vcpu, unsigned long flags,
672 		      unsigned long pte_index, unsigned long avpn)
673 {
674 	struct kvm *kvm = vcpu->kvm;
675 	__be64 *hpte;
676 	struct revmap_entry *rev;
677 	unsigned long v, r, rb, mask, bits;
678 	u64 pte_v, pte_r;
679 
680 	if (kvm_is_radix(kvm))
681 		return H_FUNCTION;
682 	if (pte_index >= kvmppc_hpt_npte(&kvm->arch.hpt))
683 		return H_PARAMETER;
684 
685 	hpte = (__be64 *)(kvm->arch.hpt.virt + (pte_index << 4));
686 	while (!try_lock_hpte(hpte, HPTE_V_HVLOCK))
687 		cpu_relax();
688 	v = pte_v = be64_to_cpu(hpte[0]);
689 	if (cpu_has_feature(CPU_FTR_ARCH_300))
690 		v = hpte_new_to_old_v(v, be64_to_cpu(hpte[1]));
691 	if ((v & (HPTE_V_ABSENT | HPTE_V_VALID)) == 0 ||
692 	    ((flags & H_AVPN) && (v & ~0x7fUL) != avpn)) {
693 		__unlock_hpte(hpte, pte_v);
694 		return H_NOT_FOUND;
695 	}
696 
697 	pte_r = be64_to_cpu(hpte[1]);
698 	bits = (flags << 55) & HPTE_R_PP0;
699 	bits |= (flags << 48) & HPTE_R_KEY_HI;
700 	bits |= flags & (HPTE_R_PP | HPTE_R_N | HPTE_R_KEY_LO);
701 
702 	/* Update guest view of 2nd HPTE dword */
703 	mask = HPTE_R_PP0 | HPTE_R_PP | HPTE_R_N |
704 		HPTE_R_KEY_HI | HPTE_R_KEY_LO;
705 	rev = real_vmalloc_addr(&kvm->arch.hpt.rev[pte_index]);
706 	if (rev) {
707 		r = (rev->guest_rpte & ~mask) | bits;
708 		rev->guest_rpte = r;
709 		note_hpte_modification(kvm, rev);
710 	}
711 
712 	/* Update HPTE */
713 	if (v & HPTE_V_VALID) {
714 		/*
715 		 * If the page is valid, don't let it transition from
716 		 * readonly to writable.  If it should be writable, we'll
717 		 * take a trap and let the page fault code sort it out.
718 		 */
719 		r = (pte_r & ~mask) | bits;
720 		if (hpte_is_writable(r) && !hpte_is_writable(pte_r))
721 			r = hpte_make_readonly(r);
722 		/* If the PTE is changing, invalidate it first */
723 		if (r != pte_r) {
724 			rb = compute_tlbie_rb(v, r, pte_index);
725 			hpte[0] = cpu_to_be64((pte_v & ~HPTE_V_VALID) |
726 					      HPTE_V_ABSENT);
727 			do_tlbies(kvm, &rb, 1, global_invalidates(kvm), true);
728 			/* Don't lose R/C bit updates done by hardware */
729 			r |= be64_to_cpu(hpte[1]) & (HPTE_R_R | HPTE_R_C);
730 			hpte[1] = cpu_to_be64(r);
731 		}
732 	}
733 	unlock_hpte(hpte, pte_v & ~HPTE_V_HVLOCK);
734 	asm volatile("ptesync" : : : "memory");
735 	if (is_mmio_hpte(v, pte_r))
736 		atomic64_inc(&kvm->arch.mmio_update);
737 
738 	return H_SUCCESS;
739 }
740 EXPORT_SYMBOL_GPL(kvmppc_h_protect);
741 
742 long kvmppc_h_read(struct kvm_vcpu *vcpu, unsigned long flags,
743 		   unsigned long pte_index)
744 {
745 	struct kvm *kvm = vcpu->kvm;
746 	__be64 *hpte;
747 	unsigned long v, r;
748 	int i, n = 1;
749 	struct revmap_entry *rev = NULL;
750 
751 	if (kvm_is_radix(kvm))
752 		return H_FUNCTION;
753 	if (pte_index >= kvmppc_hpt_npte(&kvm->arch.hpt))
754 		return H_PARAMETER;
755 	if (flags & H_READ_4) {
756 		pte_index &= ~3;
757 		n = 4;
758 	}
759 	rev = real_vmalloc_addr(&kvm->arch.hpt.rev[pte_index]);
760 	for (i = 0; i < n; ++i, ++pte_index) {
761 		hpte = (__be64 *)(kvm->arch.hpt.virt + (pte_index << 4));
762 		v = be64_to_cpu(hpte[0]) & ~HPTE_V_HVLOCK;
763 		r = be64_to_cpu(hpte[1]);
764 		if (cpu_has_feature(CPU_FTR_ARCH_300)) {
765 			v = hpte_new_to_old_v(v, r);
766 			r = hpte_new_to_old_r(r);
767 		}
768 		if (v & HPTE_V_ABSENT) {
769 			v &= ~HPTE_V_ABSENT;
770 			v |= HPTE_V_VALID;
771 		}
772 		if (v & HPTE_V_VALID) {
773 			r = rev[i].guest_rpte | (r & (HPTE_R_R | HPTE_R_C));
774 			r &= ~HPTE_GR_RESERVED;
775 		}
776 		vcpu->arch.regs.gpr[4 + i * 2] = v;
777 		vcpu->arch.regs.gpr[5 + i * 2] = r;
778 	}
779 	return H_SUCCESS;
780 }
781 EXPORT_SYMBOL_GPL(kvmppc_h_read);
782 
783 long kvmppc_h_clear_ref(struct kvm_vcpu *vcpu, unsigned long flags,
784 			unsigned long pte_index)
785 {
786 	struct kvm *kvm = vcpu->kvm;
787 	__be64 *hpte;
788 	unsigned long v, r, gr;
789 	struct revmap_entry *rev;
790 	unsigned long *rmap;
791 	long ret = H_NOT_FOUND;
792 
793 	if (kvm_is_radix(kvm))
794 		return H_FUNCTION;
795 	if (pte_index >= kvmppc_hpt_npte(&kvm->arch.hpt))
796 		return H_PARAMETER;
797 
798 	rev = real_vmalloc_addr(&kvm->arch.hpt.rev[pte_index]);
799 	hpte = (__be64 *)(kvm->arch.hpt.virt + (pte_index << 4));
800 	while (!try_lock_hpte(hpte, HPTE_V_HVLOCK))
801 		cpu_relax();
802 	v = be64_to_cpu(hpte[0]);
803 	r = be64_to_cpu(hpte[1]);
804 	if (!(v & (HPTE_V_VALID | HPTE_V_ABSENT)))
805 		goto out;
806 
807 	gr = rev->guest_rpte;
808 	if (rev->guest_rpte & HPTE_R_R) {
809 		rev->guest_rpte &= ~HPTE_R_R;
810 		note_hpte_modification(kvm, rev);
811 	}
812 	if (v & HPTE_V_VALID) {
813 		gr |= r & (HPTE_R_R | HPTE_R_C);
814 		if (r & HPTE_R_R) {
815 			kvmppc_clear_ref_hpte(kvm, hpte, pte_index);
816 			rmap = revmap_for_hpte(kvm, v, gr, NULL, NULL);
817 			if (rmap) {
818 				lock_rmap(rmap);
819 				*rmap |= KVMPPC_RMAP_REFERENCED;
820 				unlock_rmap(rmap);
821 			}
822 		}
823 	}
824 	vcpu->arch.regs.gpr[4] = gr;
825 	ret = H_SUCCESS;
826  out:
827 	unlock_hpte(hpte, v & ~HPTE_V_HVLOCK);
828 	return ret;
829 }
830 EXPORT_SYMBOL_GPL(kvmppc_h_clear_ref);
831 
832 long kvmppc_h_clear_mod(struct kvm_vcpu *vcpu, unsigned long flags,
833 			unsigned long pte_index)
834 {
835 	struct kvm *kvm = vcpu->kvm;
836 	__be64 *hpte;
837 	unsigned long v, r, gr;
838 	struct revmap_entry *rev;
839 	long ret = H_NOT_FOUND;
840 
841 	if (kvm_is_radix(kvm))
842 		return H_FUNCTION;
843 	if (pte_index >= kvmppc_hpt_npte(&kvm->arch.hpt))
844 		return H_PARAMETER;
845 
846 	rev = real_vmalloc_addr(&kvm->arch.hpt.rev[pte_index]);
847 	hpte = (__be64 *)(kvm->arch.hpt.virt + (pte_index << 4));
848 	while (!try_lock_hpte(hpte, HPTE_V_HVLOCK))
849 		cpu_relax();
850 	v = be64_to_cpu(hpte[0]);
851 	r = be64_to_cpu(hpte[1]);
852 	if (!(v & (HPTE_V_VALID | HPTE_V_ABSENT)))
853 		goto out;
854 
855 	gr = rev->guest_rpte;
856 	if (gr & HPTE_R_C) {
857 		rev->guest_rpte &= ~HPTE_R_C;
858 		note_hpte_modification(kvm, rev);
859 	}
860 	if (v & HPTE_V_VALID) {
861 		/* need to make it temporarily absent so C is stable */
862 		hpte[0] |= cpu_to_be64(HPTE_V_ABSENT);
863 		kvmppc_invalidate_hpte(kvm, hpte, pte_index);
864 		r = be64_to_cpu(hpte[1]);
865 		gr |= r & (HPTE_R_R | HPTE_R_C);
866 		if (r & HPTE_R_C) {
867 			hpte[1] = cpu_to_be64(r & ~HPTE_R_C);
868 			eieio();
869 			kvmppc_set_dirty_from_hpte(kvm, v, gr);
870 		}
871 	}
872 	vcpu->arch.regs.gpr[4] = gr;
873 	ret = H_SUCCESS;
874  out:
875 	unlock_hpte(hpte, v & ~HPTE_V_HVLOCK);
876 	return ret;
877 }
878 EXPORT_SYMBOL_GPL(kvmppc_h_clear_mod);
879 
880 static int kvmppc_get_hpa(struct kvm_vcpu *vcpu, unsigned long mmu_seq,
881 			  unsigned long gpa, int writing, unsigned long *hpa,
882 			  struct kvm_memory_slot **memslot_p)
883 {
884 	struct kvm *kvm = vcpu->kvm;
885 	struct kvm_memory_slot *memslot;
886 	unsigned long gfn, hva, pa, psize = PAGE_SHIFT;
887 	unsigned int shift;
888 	pte_t *ptep, pte;
889 
890 	/* Find the memslot for this address */
891 	gfn = gpa >> PAGE_SHIFT;
892 	memslot = __gfn_to_memslot(kvm_memslots_raw(kvm), gfn);
893 	if (!memslot || (memslot->flags & KVM_MEMSLOT_INVALID))
894 		return H_PARAMETER;
895 
896 	/* Translate to host virtual address */
897 	hva = __gfn_to_hva_memslot(memslot, gfn);
898 
899 	/* Try to find the host pte for that virtual address */
900 	ptep = find_kvm_host_pte(kvm, mmu_seq, hva, &shift);
901 	if (!ptep)
902 		return H_TOO_HARD;
903 	pte = kvmppc_read_update_linux_pte(ptep, writing);
904 	if (!pte_present(pte))
905 		return H_TOO_HARD;
906 
907 	/* Convert to a physical address */
908 	if (shift)
909 		psize = 1UL << shift;
910 	pa = pte_pfn(pte) << PAGE_SHIFT;
911 	pa |= hva & (psize - 1);
912 	pa |= gpa & ~PAGE_MASK;
913 
914 	if (hpa)
915 		*hpa = pa;
916 	if (memslot_p)
917 		*memslot_p = memslot;
918 
919 	return H_SUCCESS;
920 }
921 
922 static long kvmppc_do_h_page_init_zero(struct kvm_vcpu *vcpu,
923 				       unsigned long dest)
924 {
925 	struct kvm_memory_slot *memslot;
926 	struct kvm *kvm = vcpu->kvm;
927 	unsigned long pa, mmu_seq;
928 	long ret = H_SUCCESS;
929 	int i;
930 
931 	/* Used later to detect if we might have been invalidated */
932 	mmu_seq = kvm->mmu_notifier_seq;
933 	smp_rmb();
934 
935 	arch_spin_lock(&kvm->mmu_lock.rlock.raw_lock);
936 
937 	ret = kvmppc_get_hpa(vcpu, mmu_seq, dest, 1, &pa, &memslot);
938 	if (ret != H_SUCCESS)
939 		goto out_unlock;
940 
941 	/* Zero the page */
942 	for (i = 0; i < SZ_4K; i += L1_CACHE_BYTES, pa += L1_CACHE_BYTES)
943 		dcbz((void *)pa);
944 	kvmppc_update_dirty_map(memslot, dest >> PAGE_SHIFT, PAGE_SIZE);
945 
946 out_unlock:
947 	arch_spin_unlock(&kvm->mmu_lock.rlock.raw_lock);
948 	return ret;
949 }
950 
951 static long kvmppc_do_h_page_init_copy(struct kvm_vcpu *vcpu,
952 				       unsigned long dest, unsigned long src)
953 {
954 	unsigned long dest_pa, src_pa, mmu_seq;
955 	struct kvm_memory_slot *dest_memslot;
956 	struct kvm *kvm = vcpu->kvm;
957 	long ret = H_SUCCESS;
958 
959 	/* Used later to detect if we might have been invalidated */
960 	mmu_seq = kvm->mmu_notifier_seq;
961 	smp_rmb();
962 
963 	arch_spin_lock(&kvm->mmu_lock.rlock.raw_lock);
964 	ret = kvmppc_get_hpa(vcpu, mmu_seq, dest, 1, &dest_pa, &dest_memslot);
965 	if (ret != H_SUCCESS)
966 		goto out_unlock;
967 
968 	ret = kvmppc_get_hpa(vcpu, mmu_seq, src, 0, &src_pa, NULL);
969 	if (ret != H_SUCCESS)
970 		goto out_unlock;
971 
972 	/* Copy the page */
973 	memcpy((void *)dest_pa, (void *)src_pa, SZ_4K);
974 
975 	kvmppc_update_dirty_map(dest_memslot, dest >> PAGE_SHIFT, PAGE_SIZE);
976 
977 out_unlock:
978 	arch_spin_unlock(&kvm->mmu_lock.rlock.raw_lock);
979 	return ret;
980 }
981 
982 long kvmppc_rm_h_page_init(struct kvm_vcpu *vcpu, unsigned long flags,
983 			   unsigned long dest, unsigned long src)
984 {
985 	struct kvm *kvm = vcpu->kvm;
986 	u64 pg_mask = SZ_4K - 1;	/* 4K page size */
987 	long ret = H_SUCCESS;
988 
989 	/* Don't handle radix mode here, go up to the virtual mode handler */
990 	if (kvm_is_radix(kvm))
991 		return H_TOO_HARD;
992 
993 	/* Check for invalid flags (H_PAGE_SET_LOANED covers all CMO flags) */
994 	if (flags & ~(H_ICACHE_INVALIDATE | H_ICACHE_SYNCHRONIZE |
995 		      H_ZERO_PAGE | H_COPY_PAGE | H_PAGE_SET_LOANED))
996 		return H_PARAMETER;
997 
998 	/* dest (and src if copy_page flag set) must be page aligned */
999 	if ((dest & pg_mask) || ((flags & H_COPY_PAGE) && (src & pg_mask)))
1000 		return H_PARAMETER;
1001 
1002 	/* zero and/or copy the page as determined by the flags */
1003 	if (flags & H_COPY_PAGE)
1004 		ret = kvmppc_do_h_page_init_copy(vcpu, dest, src);
1005 	else if (flags & H_ZERO_PAGE)
1006 		ret = kvmppc_do_h_page_init_zero(vcpu, dest);
1007 
1008 	/* We can ignore the other flags */
1009 
1010 	return ret;
1011 }
1012 
1013 void kvmppc_invalidate_hpte(struct kvm *kvm, __be64 *hptep,
1014 			unsigned long pte_index)
1015 {
1016 	unsigned long rb;
1017 	u64 hp0, hp1;
1018 
1019 	hptep[0] &= ~cpu_to_be64(HPTE_V_VALID);
1020 	hp0 = be64_to_cpu(hptep[0]);
1021 	hp1 = be64_to_cpu(hptep[1]);
1022 	if (cpu_has_feature(CPU_FTR_ARCH_300)) {
1023 		hp0 = hpte_new_to_old_v(hp0, hp1);
1024 		hp1 = hpte_new_to_old_r(hp1);
1025 	}
1026 	rb = compute_tlbie_rb(hp0, hp1, pte_index);
1027 	do_tlbies(kvm, &rb, 1, 1, true);
1028 }
1029 EXPORT_SYMBOL_GPL(kvmppc_invalidate_hpte);
1030 
1031 void kvmppc_clear_ref_hpte(struct kvm *kvm, __be64 *hptep,
1032 			   unsigned long pte_index)
1033 {
1034 	unsigned long rb;
1035 	unsigned char rbyte;
1036 	u64 hp0, hp1;
1037 
1038 	hp0 = be64_to_cpu(hptep[0]);
1039 	hp1 = be64_to_cpu(hptep[1]);
1040 	if (cpu_has_feature(CPU_FTR_ARCH_300)) {
1041 		hp0 = hpte_new_to_old_v(hp0, hp1);
1042 		hp1 = hpte_new_to_old_r(hp1);
1043 	}
1044 	rb = compute_tlbie_rb(hp0, hp1, pte_index);
1045 	rbyte = (be64_to_cpu(hptep[1]) & ~HPTE_R_R) >> 8;
1046 	/* modify only the second-last byte, which contains the ref bit */
1047 	*((char *)hptep + 14) = rbyte;
1048 	do_tlbies(kvm, &rb, 1, 1, false);
1049 }
1050 EXPORT_SYMBOL_GPL(kvmppc_clear_ref_hpte);
1051 
1052 static int slb_base_page_shift[4] = {
1053 	24,	/* 16M */
1054 	16,	/* 64k */
1055 	34,	/* 16G */
1056 	20,	/* 1M, unsupported */
1057 };
1058 
1059 static struct mmio_hpte_cache_entry *mmio_cache_search(struct kvm_vcpu *vcpu,
1060 		unsigned long eaddr, unsigned long slb_v, long mmio_update)
1061 {
1062 	struct mmio_hpte_cache_entry *entry = NULL;
1063 	unsigned int pshift;
1064 	unsigned int i;
1065 
1066 	for (i = 0; i < MMIO_HPTE_CACHE_SIZE; i++) {
1067 		entry = &vcpu->arch.mmio_cache.entry[i];
1068 		if (entry->mmio_update == mmio_update) {
1069 			pshift = entry->slb_base_pshift;
1070 			if ((entry->eaddr >> pshift) == (eaddr >> pshift) &&
1071 			    entry->slb_v == slb_v)
1072 				return entry;
1073 		}
1074 	}
1075 	return NULL;
1076 }
1077 
1078 static struct mmio_hpte_cache_entry *
1079 			next_mmio_cache_entry(struct kvm_vcpu *vcpu)
1080 {
1081 	unsigned int index = vcpu->arch.mmio_cache.index;
1082 
1083 	vcpu->arch.mmio_cache.index++;
1084 	if (vcpu->arch.mmio_cache.index == MMIO_HPTE_CACHE_SIZE)
1085 		vcpu->arch.mmio_cache.index = 0;
1086 
1087 	return &vcpu->arch.mmio_cache.entry[index];
1088 }
1089 
1090 /* When called from virtmode, this func should be protected by
1091  * preempt_disable(), otherwise, the holding of HPTE_V_HVLOCK
1092  * can trigger deadlock issue.
1093  */
1094 long kvmppc_hv_find_lock_hpte(struct kvm *kvm, gva_t eaddr, unsigned long slb_v,
1095 			      unsigned long valid)
1096 {
1097 	unsigned int i;
1098 	unsigned int pshift;
1099 	unsigned long somask;
1100 	unsigned long vsid, hash;
1101 	unsigned long avpn;
1102 	__be64 *hpte;
1103 	unsigned long mask, val;
1104 	unsigned long v, r, orig_v;
1105 
1106 	/* Get page shift, work out hash and AVPN etc. */
1107 	mask = SLB_VSID_B | HPTE_V_AVPN | HPTE_V_SECONDARY;
1108 	val = 0;
1109 	pshift = 12;
1110 	if (slb_v & SLB_VSID_L) {
1111 		mask |= HPTE_V_LARGE;
1112 		val |= HPTE_V_LARGE;
1113 		pshift = slb_base_page_shift[(slb_v & SLB_VSID_LP) >> 4];
1114 	}
1115 	if (slb_v & SLB_VSID_B_1T) {
1116 		somask = (1UL << 40) - 1;
1117 		vsid = (slb_v & ~SLB_VSID_B) >> SLB_VSID_SHIFT_1T;
1118 		vsid ^= vsid << 25;
1119 	} else {
1120 		somask = (1UL << 28) - 1;
1121 		vsid = (slb_v & ~SLB_VSID_B) >> SLB_VSID_SHIFT;
1122 	}
1123 	hash = (vsid ^ ((eaddr & somask) >> pshift)) & kvmppc_hpt_mask(&kvm->arch.hpt);
1124 	avpn = slb_v & ~(somask >> 16);	/* also includes B */
1125 	avpn |= (eaddr & somask) >> 16;
1126 
1127 	if (pshift >= 24)
1128 		avpn &= ~((1UL << (pshift - 16)) - 1);
1129 	else
1130 		avpn &= ~0x7fUL;
1131 	val |= avpn;
1132 
1133 	for (;;) {
1134 		hpte = (__be64 *)(kvm->arch.hpt.virt + (hash << 7));
1135 
1136 		for (i = 0; i < 16; i += 2) {
1137 			/* Read the PTE racily */
1138 			v = be64_to_cpu(hpte[i]) & ~HPTE_V_HVLOCK;
1139 			if (cpu_has_feature(CPU_FTR_ARCH_300))
1140 				v = hpte_new_to_old_v(v, be64_to_cpu(hpte[i+1]));
1141 
1142 			/* Check valid/absent, hash, segment size and AVPN */
1143 			if (!(v & valid) || (v & mask) != val)
1144 				continue;
1145 
1146 			/* Lock the PTE and read it under the lock */
1147 			while (!try_lock_hpte(&hpte[i], HPTE_V_HVLOCK))
1148 				cpu_relax();
1149 			v = orig_v = be64_to_cpu(hpte[i]) & ~HPTE_V_HVLOCK;
1150 			r = be64_to_cpu(hpte[i+1]);
1151 			if (cpu_has_feature(CPU_FTR_ARCH_300)) {
1152 				v = hpte_new_to_old_v(v, r);
1153 				r = hpte_new_to_old_r(r);
1154 			}
1155 
1156 			/*
1157 			 * Check the HPTE again, including base page size
1158 			 */
1159 			if ((v & valid) && (v & mask) == val &&
1160 			    kvmppc_hpte_base_page_shift(v, r) == pshift)
1161 				/* Return with the HPTE still locked */
1162 				return (hash << 3) + (i >> 1);
1163 
1164 			__unlock_hpte(&hpte[i], orig_v);
1165 		}
1166 
1167 		if (val & HPTE_V_SECONDARY)
1168 			break;
1169 		val |= HPTE_V_SECONDARY;
1170 		hash = hash ^ kvmppc_hpt_mask(&kvm->arch.hpt);
1171 	}
1172 	return -1;
1173 }
1174 EXPORT_SYMBOL(kvmppc_hv_find_lock_hpte);
1175 
1176 /*
1177  * Called in real mode to check whether an HPTE not found fault
1178  * is due to accessing a paged-out page or an emulated MMIO page,
1179  * or if a protection fault is due to accessing a page that the
1180  * guest wanted read/write access to but which we made read-only.
1181  * Returns a possibly modified status (DSISR) value if not
1182  * (i.e. pass the interrupt to the guest),
1183  * -1 to pass the fault up to host kernel mode code, -2 to do that
1184  * and also load the instruction word (for MMIO emulation),
1185  * or 0 if we should make the guest retry the access.
1186  */
1187 long kvmppc_hpte_hv_fault(struct kvm_vcpu *vcpu, unsigned long addr,
1188 			  unsigned long slb_v, unsigned int status, bool data)
1189 {
1190 	struct kvm *kvm = vcpu->kvm;
1191 	long int index;
1192 	unsigned long v, r, gr, orig_v;
1193 	__be64 *hpte;
1194 	unsigned long valid;
1195 	struct revmap_entry *rev;
1196 	unsigned long pp, key;
1197 	struct mmio_hpte_cache_entry *cache_entry = NULL;
1198 	long mmio_update = 0;
1199 
1200 	/* For protection fault, expect to find a valid HPTE */
1201 	valid = HPTE_V_VALID;
1202 	if (status & DSISR_NOHPTE) {
1203 		valid |= HPTE_V_ABSENT;
1204 		mmio_update = atomic64_read(&kvm->arch.mmio_update);
1205 		cache_entry = mmio_cache_search(vcpu, addr, slb_v, mmio_update);
1206 	}
1207 	if (cache_entry) {
1208 		index = cache_entry->pte_index;
1209 		v = cache_entry->hpte_v;
1210 		r = cache_entry->hpte_r;
1211 		gr = cache_entry->rpte;
1212 	} else {
1213 		index = kvmppc_hv_find_lock_hpte(kvm, addr, slb_v, valid);
1214 		if (index < 0) {
1215 			if (status & DSISR_NOHPTE)
1216 				return status;	/* there really was no HPTE */
1217 			return 0;	/* for prot fault, HPTE disappeared */
1218 		}
1219 		hpte = (__be64 *)(kvm->arch.hpt.virt + (index << 4));
1220 		v = orig_v = be64_to_cpu(hpte[0]) & ~HPTE_V_HVLOCK;
1221 		r = be64_to_cpu(hpte[1]);
1222 		if (cpu_has_feature(CPU_FTR_ARCH_300)) {
1223 			v = hpte_new_to_old_v(v, r);
1224 			r = hpte_new_to_old_r(r);
1225 		}
1226 		rev = real_vmalloc_addr(&kvm->arch.hpt.rev[index]);
1227 		gr = rev->guest_rpte;
1228 
1229 		unlock_hpte(hpte, orig_v);
1230 	}
1231 
1232 	/* For not found, if the HPTE is valid by now, retry the instruction */
1233 	if ((status & DSISR_NOHPTE) && (v & HPTE_V_VALID))
1234 		return 0;
1235 
1236 	/* Check access permissions to the page */
1237 	pp = gr & (HPTE_R_PP0 | HPTE_R_PP);
1238 	key = (vcpu->arch.shregs.msr & MSR_PR) ? SLB_VSID_KP : SLB_VSID_KS;
1239 	status &= ~DSISR_NOHPTE;	/* DSISR_NOHPTE == SRR1_ISI_NOPT */
1240 	if (!data) {
1241 		if (gr & (HPTE_R_N | HPTE_R_G))
1242 			return status | SRR1_ISI_N_G_OR_CIP;
1243 		if (!hpte_read_permission(pp, slb_v & key))
1244 			return status | SRR1_ISI_PROT;
1245 	} else if (status & DSISR_ISSTORE) {
1246 		/* check write permission */
1247 		if (!hpte_write_permission(pp, slb_v & key))
1248 			return status | DSISR_PROTFAULT;
1249 	} else {
1250 		if (!hpte_read_permission(pp, slb_v & key))
1251 			return status | DSISR_PROTFAULT;
1252 	}
1253 
1254 	/* Check storage key, if applicable */
1255 	if (data && (vcpu->arch.shregs.msr & MSR_DR)) {
1256 		unsigned int perm = hpte_get_skey_perm(gr, vcpu->arch.amr);
1257 		if (status & DSISR_ISSTORE)
1258 			perm >>= 1;
1259 		if (perm & 1)
1260 			return status | DSISR_KEYFAULT;
1261 	}
1262 
1263 	/* Save HPTE info for virtual-mode handler */
1264 	vcpu->arch.pgfault_addr = addr;
1265 	vcpu->arch.pgfault_index = index;
1266 	vcpu->arch.pgfault_hpte[0] = v;
1267 	vcpu->arch.pgfault_hpte[1] = r;
1268 	vcpu->arch.pgfault_cache = cache_entry;
1269 
1270 	/* Check the storage key to see if it is possibly emulated MMIO */
1271 	if ((r & (HPTE_R_KEY_HI | HPTE_R_KEY_LO)) ==
1272 	    (HPTE_R_KEY_HI | HPTE_R_KEY_LO)) {
1273 		if (!cache_entry) {
1274 			unsigned int pshift = 12;
1275 			unsigned int pshift_index;
1276 
1277 			if (slb_v & SLB_VSID_L) {
1278 				pshift_index = ((slb_v & SLB_VSID_LP) >> 4);
1279 				pshift = slb_base_page_shift[pshift_index];
1280 			}
1281 			cache_entry = next_mmio_cache_entry(vcpu);
1282 			cache_entry->eaddr = addr;
1283 			cache_entry->slb_base_pshift = pshift;
1284 			cache_entry->pte_index = index;
1285 			cache_entry->hpte_v = v;
1286 			cache_entry->hpte_r = r;
1287 			cache_entry->rpte = gr;
1288 			cache_entry->slb_v = slb_v;
1289 			cache_entry->mmio_update = mmio_update;
1290 		}
1291 		if (data && (vcpu->arch.shregs.msr & MSR_IR))
1292 			return -2;	/* MMIO emulation - load instr word */
1293 	}
1294 
1295 	return -1;		/* send fault up to host kernel mode */
1296 }
1297 EXPORT_SYMBOL_GPL(kvmppc_hpte_hv_fault);
1298