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