1 /*
2  * This program is free software; you can redistribute it and/or modify
3  * it under the terms of the GNU General Public License, version 2, as
4  * published by the Free Software Foundation.
5  *
6  * Copyright 2016 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com>
7  */
8 
9 #include <linux/types.h>
10 #include <linux/string.h>
11 #include <linux/kvm.h>
12 #include <linux/kvm_host.h>
13 
14 #include <asm/kvm_ppc.h>
15 #include <asm/kvm_book3s.h>
16 #include <asm/page.h>
17 #include <asm/mmu.h>
18 #include <asm/pgtable.h>
19 #include <asm/pgalloc.h>
20 #include <asm/pte-walk.h>
21 
22 /*
23  * Supported radix tree geometry.
24  * Like p9, we support either 5 or 9 bits at the first (lowest) level,
25  * for a page size of 64k or 4k.
26  */
27 static int p9_supported_radix_bits[4] = { 5, 9, 9, 13 };
28 
29 int kvmppc_mmu_radix_xlate(struct kvm_vcpu *vcpu, gva_t eaddr,
30 			   struct kvmppc_pte *gpte, bool data, bool iswrite)
31 {
32 	struct kvm *kvm = vcpu->kvm;
33 	u32 pid;
34 	int ret, level, ps;
35 	__be64 prte, rpte;
36 	unsigned long ptbl;
37 	unsigned long root, pte, index;
38 	unsigned long rts, bits, offset;
39 	unsigned long gpa;
40 	unsigned long proc_tbl_size;
41 
42 	/* Work out effective PID */
43 	switch (eaddr >> 62) {
44 	case 0:
45 		pid = vcpu->arch.pid;
46 		break;
47 	case 3:
48 		pid = 0;
49 		break;
50 	default:
51 		return -EINVAL;
52 	}
53 	proc_tbl_size = 1 << ((kvm->arch.process_table & PRTS_MASK) + 12);
54 	if (pid * 16 >= proc_tbl_size)
55 		return -EINVAL;
56 
57 	/* Read partition table to find root of tree for effective PID */
58 	ptbl = (kvm->arch.process_table & PRTB_MASK) + (pid * 16);
59 	ret = kvm_read_guest(kvm, ptbl, &prte, sizeof(prte));
60 	if (ret)
61 		return ret;
62 
63 	root = be64_to_cpu(prte);
64 	rts = ((root & RTS1_MASK) >> (RTS1_SHIFT - 3)) |
65 		((root & RTS2_MASK) >> RTS2_SHIFT);
66 	bits = root & RPDS_MASK;
67 	root = root & RPDB_MASK;
68 
69 	/* P9 DD1 interprets RTS (radix tree size) differently */
70 	offset = rts + 31;
71 	if (cpu_has_feature(CPU_FTR_POWER9_DD1))
72 		offset -= 3;
73 
74 	/* current implementations only support 52-bit space */
75 	if (offset != 52)
76 		return -EINVAL;
77 
78 	for (level = 3; level >= 0; --level) {
79 		if (level && bits != p9_supported_radix_bits[level])
80 			return -EINVAL;
81 		if (level == 0 && !(bits == 5 || bits == 9))
82 			return -EINVAL;
83 		offset -= bits;
84 		index = (eaddr >> offset) & ((1UL << bits) - 1);
85 		/* check that low bits of page table base are zero */
86 		if (root & ((1UL << (bits + 3)) - 1))
87 			return -EINVAL;
88 		ret = kvm_read_guest(kvm, root + index * 8,
89 				     &rpte, sizeof(rpte));
90 		if (ret)
91 			return ret;
92 		pte = __be64_to_cpu(rpte);
93 		if (!(pte & _PAGE_PRESENT))
94 			return -ENOENT;
95 		if (pte & _PAGE_PTE)
96 			break;
97 		bits = pte & 0x1f;
98 		root = pte & 0x0fffffffffffff00ul;
99 	}
100 	/* need a leaf at lowest level; 512GB pages not supported */
101 	if (level < 0 || level == 3)
102 		return -EINVAL;
103 
104 	/* offset is now log base 2 of the page size */
105 	gpa = pte & 0x01fffffffffff000ul;
106 	if (gpa & ((1ul << offset) - 1))
107 		return -EINVAL;
108 	gpa += eaddr & ((1ul << offset) - 1);
109 	for (ps = MMU_PAGE_4K; ps < MMU_PAGE_COUNT; ++ps)
110 		if (offset == mmu_psize_defs[ps].shift)
111 			break;
112 	gpte->page_size = ps;
113 
114 	gpte->eaddr = eaddr;
115 	gpte->raddr = gpa;
116 
117 	/* Work out permissions */
118 	gpte->may_read = !!(pte & _PAGE_READ);
119 	gpte->may_write = !!(pte & _PAGE_WRITE);
120 	gpte->may_execute = !!(pte & _PAGE_EXEC);
121 	if (kvmppc_get_msr(vcpu) & MSR_PR) {
122 		if (pte & _PAGE_PRIVILEGED) {
123 			gpte->may_read = 0;
124 			gpte->may_write = 0;
125 			gpte->may_execute = 0;
126 		}
127 	} else {
128 		if (!(pte & _PAGE_PRIVILEGED)) {
129 			/* Check AMR/IAMR to see if strict mode is in force */
130 			if (vcpu->arch.amr & (1ul << 62))
131 				gpte->may_read = 0;
132 			if (vcpu->arch.amr & (1ul << 63))
133 				gpte->may_write = 0;
134 			if (vcpu->arch.iamr & (1ul << 62))
135 				gpte->may_execute = 0;
136 		}
137 	}
138 
139 	return 0;
140 }
141 
142 #ifdef CONFIG_PPC_64K_PAGES
143 #define MMU_BASE_PSIZE	MMU_PAGE_64K
144 #else
145 #define MMU_BASE_PSIZE	MMU_PAGE_4K
146 #endif
147 
148 static void kvmppc_radix_tlbie_page(struct kvm *kvm, unsigned long addr,
149 				    unsigned int pshift)
150 {
151 	int psize = MMU_BASE_PSIZE;
152 
153 	if (pshift >= PMD_SHIFT)
154 		psize = MMU_PAGE_2M;
155 	addr &= ~0xfffUL;
156 	addr |= mmu_psize_defs[psize].ap << 5;
157 	asm volatile("ptesync": : :"memory");
158 	asm volatile(PPC_TLBIE_5(%0, %1, 0, 0, 1)
159 		     : : "r" (addr), "r" (kvm->arch.lpid) : "memory");
160 	asm volatile("ptesync": : :"memory");
161 }
162 
163 unsigned long kvmppc_radix_update_pte(struct kvm *kvm, pte_t *ptep,
164 				      unsigned long clr, unsigned long set,
165 				      unsigned long addr, unsigned int shift)
166 {
167 	unsigned long old = 0;
168 
169 	if (!(clr & _PAGE_PRESENT) && cpu_has_feature(CPU_FTR_POWER9_DD1) &&
170 	    pte_present(*ptep)) {
171 		/* have to invalidate it first */
172 		old = __radix_pte_update(ptep, _PAGE_PRESENT, 0);
173 		kvmppc_radix_tlbie_page(kvm, addr, shift);
174 		set |= _PAGE_PRESENT;
175 		old &= _PAGE_PRESENT;
176 	}
177 	return __radix_pte_update(ptep, clr, set) | old;
178 }
179 
180 void kvmppc_radix_set_pte_at(struct kvm *kvm, unsigned long addr,
181 			     pte_t *ptep, pte_t pte)
182 {
183 	radix__set_pte_at(kvm->mm, addr, ptep, pte, 0);
184 }
185 
186 static struct kmem_cache *kvm_pte_cache;
187 
188 static pte_t *kvmppc_pte_alloc(void)
189 {
190 	return kmem_cache_alloc(kvm_pte_cache, GFP_KERNEL);
191 }
192 
193 static void kvmppc_pte_free(pte_t *ptep)
194 {
195 	kmem_cache_free(kvm_pte_cache, ptep);
196 }
197 
198 static int kvmppc_create_pte(struct kvm *kvm, pte_t pte, unsigned long gpa,
199 			     unsigned int level, unsigned long mmu_seq)
200 {
201 	pgd_t *pgd;
202 	pud_t *pud, *new_pud = NULL;
203 	pmd_t *pmd, *new_pmd = NULL;
204 	pte_t *ptep, *new_ptep = NULL;
205 	unsigned long old;
206 	int ret;
207 
208 	/* Traverse the guest's 2nd-level tree, allocate new levels needed */
209 	pgd = kvm->arch.pgtable + pgd_index(gpa);
210 	pud = NULL;
211 	if (pgd_present(*pgd))
212 		pud = pud_offset(pgd, gpa);
213 	else
214 		new_pud = pud_alloc_one(kvm->mm, gpa);
215 
216 	pmd = NULL;
217 	if (pud && pud_present(*pud))
218 		pmd = pmd_offset(pud, gpa);
219 	else
220 		new_pmd = pmd_alloc_one(kvm->mm, gpa);
221 
222 	if (level == 0 && !(pmd && pmd_present(*pmd)))
223 		new_ptep = kvmppc_pte_alloc();
224 
225 	/* Check if we might have been invalidated; let the guest retry if so */
226 	spin_lock(&kvm->mmu_lock);
227 	ret = -EAGAIN;
228 	if (mmu_notifier_retry(kvm, mmu_seq))
229 		goto out_unlock;
230 
231 	/* Now traverse again under the lock and change the tree */
232 	ret = -ENOMEM;
233 	if (pgd_none(*pgd)) {
234 		if (!new_pud)
235 			goto out_unlock;
236 		pgd_populate(kvm->mm, pgd, new_pud);
237 		new_pud = NULL;
238 	}
239 	pud = pud_offset(pgd, gpa);
240 	if (pud_none(*pud)) {
241 		if (!new_pmd)
242 			goto out_unlock;
243 		pud_populate(kvm->mm, pud, new_pmd);
244 		new_pmd = NULL;
245 	}
246 	pmd = pmd_offset(pud, gpa);
247 	if (pmd_large(*pmd)) {
248 		/* Someone else has instantiated a large page here; retry */
249 		ret = -EAGAIN;
250 		goto out_unlock;
251 	}
252 	if (level == 1 && !pmd_none(*pmd)) {
253 		/*
254 		 * There's a page table page here, but we wanted
255 		 * to install a large page.  Tell the caller and let
256 		 * it try installing a normal page if it wants.
257 		 */
258 		ret = -EBUSY;
259 		goto out_unlock;
260 	}
261 	if (level == 0) {
262 		if (pmd_none(*pmd)) {
263 			if (!new_ptep)
264 				goto out_unlock;
265 			pmd_populate(kvm->mm, pmd, new_ptep);
266 			new_ptep = NULL;
267 		}
268 		ptep = pte_offset_kernel(pmd, gpa);
269 		if (pte_present(*ptep)) {
270 			/* PTE was previously valid, so invalidate it */
271 			old = kvmppc_radix_update_pte(kvm, ptep, _PAGE_PRESENT,
272 						      0, gpa, 0);
273 			kvmppc_radix_tlbie_page(kvm, gpa, 0);
274 			if (old & _PAGE_DIRTY)
275 				mark_page_dirty(kvm, gpa >> PAGE_SHIFT);
276 		}
277 		kvmppc_radix_set_pte_at(kvm, gpa, ptep, pte);
278 	} else {
279 		kvmppc_radix_set_pte_at(kvm, gpa, pmdp_ptep(pmd), pte);
280 	}
281 	ret = 0;
282 
283  out_unlock:
284 	spin_unlock(&kvm->mmu_lock);
285 	if (new_pud)
286 		pud_free(kvm->mm, new_pud);
287 	if (new_pmd)
288 		pmd_free(kvm->mm, new_pmd);
289 	if (new_ptep)
290 		kvmppc_pte_free(new_ptep);
291 	return ret;
292 }
293 
294 int kvmppc_book3s_radix_page_fault(struct kvm_run *run, struct kvm_vcpu *vcpu,
295 				   unsigned long ea, unsigned long dsisr)
296 {
297 	struct kvm *kvm = vcpu->kvm;
298 	unsigned long mmu_seq, pte_size;
299 	unsigned long gpa, gfn, hva, pfn;
300 	struct kvm_memory_slot *memslot;
301 	struct page *page = NULL, *pages[1];
302 	long ret, npages, ok;
303 	unsigned int writing;
304 	struct vm_area_struct *vma;
305 	unsigned long flags;
306 	pte_t pte, *ptep;
307 	unsigned long pgflags;
308 	unsigned int shift, level;
309 
310 	/* Check for unusual errors */
311 	if (dsisr & DSISR_UNSUPP_MMU) {
312 		pr_err("KVM: Got unsupported MMU fault\n");
313 		return -EFAULT;
314 	}
315 	if (dsisr & DSISR_BADACCESS) {
316 		/* Reflect to the guest as DSI */
317 		pr_err("KVM: Got radix HV page fault with DSISR=%lx\n", dsisr);
318 		kvmppc_core_queue_data_storage(vcpu, ea, dsisr);
319 		return RESUME_GUEST;
320 	}
321 
322 	/* Translate the logical address and get the page */
323 	gpa = vcpu->arch.fault_gpa & ~0xfffUL;
324 	gpa &= ~0xF000000000000000ul;
325 	gfn = gpa >> PAGE_SHIFT;
326 	if (!(dsisr & DSISR_PRTABLE_FAULT))
327 		gpa |= ea & 0xfff;
328 	memslot = gfn_to_memslot(kvm, gfn);
329 
330 	/* No memslot means it's an emulated MMIO region */
331 	if (!memslot || (memslot->flags & KVM_MEMSLOT_INVALID)) {
332 		if (dsisr & (DSISR_PRTABLE_FAULT | DSISR_BADACCESS |
333 			     DSISR_SET_RC)) {
334 			/*
335 			 * Bad address in guest page table tree, or other
336 			 * unusual error - reflect it to the guest as DSI.
337 			 */
338 			kvmppc_core_queue_data_storage(vcpu, ea, dsisr);
339 			return RESUME_GUEST;
340 		}
341 		return kvmppc_hv_emulate_mmio(run, vcpu, gpa, ea,
342 					      dsisr & DSISR_ISSTORE);
343 	}
344 
345 	/* used to check for invalidations in progress */
346 	mmu_seq = kvm->mmu_notifier_seq;
347 	smp_rmb();
348 
349 	writing = (dsisr & DSISR_ISSTORE) != 0;
350 	hva = gfn_to_hva_memslot(memslot, gfn);
351 	if (dsisr & DSISR_SET_RC) {
352 		/*
353 		 * Need to set an R or C bit in the 2nd-level tables;
354 		 * if the relevant bits aren't already set in the linux
355 		 * page tables, fall through to do the gup_fast to
356 		 * set them in the linux page tables too.
357 		 */
358 		ok = 0;
359 		pgflags = _PAGE_ACCESSED;
360 		if (writing)
361 			pgflags |= _PAGE_DIRTY;
362 		local_irq_save(flags);
363 		ptep = find_current_mm_pte(current->mm->pgd, hva, NULL, NULL);
364 		if (ptep) {
365 			pte = READ_ONCE(*ptep);
366 			if (pte_present(pte) &&
367 			    (pte_val(pte) & pgflags) == pgflags)
368 				ok = 1;
369 		}
370 		local_irq_restore(flags);
371 		if (ok) {
372 			spin_lock(&kvm->mmu_lock);
373 			if (mmu_notifier_retry(vcpu->kvm, mmu_seq)) {
374 				spin_unlock(&kvm->mmu_lock);
375 				return RESUME_GUEST;
376 			}
377 			/*
378 			 * We are walking the secondary page table here. We can do this
379 			 * without disabling irq.
380 			 */
381 			ptep = __find_linux_pte(kvm->arch.pgtable,
382 						gpa, NULL, &shift);
383 			if (ptep && pte_present(*ptep)) {
384 				kvmppc_radix_update_pte(kvm, ptep, 0, pgflags,
385 							gpa, shift);
386 				spin_unlock(&kvm->mmu_lock);
387 				return RESUME_GUEST;
388 			}
389 			spin_unlock(&kvm->mmu_lock);
390 		}
391 	}
392 
393 	ret = -EFAULT;
394 	pfn = 0;
395 	pte_size = PAGE_SIZE;
396 	pgflags = _PAGE_READ | _PAGE_EXEC;
397 	level = 0;
398 	npages = get_user_pages_fast(hva, 1, writing, pages);
399 	if (npages < 1) {
400 		/* Check if it's an I/O mapping */
401 		down_read(&current->mm->mmap_sem);
402 		vma = find_vma(current->mm, hva);
403 		if (vma && vma->vm_start <= hva && hva < vma->vm_end &&
404 		    (vma->vm_flags & VM_PFNMAP)) {
405 			pfn = vma->vm_pgoff +
406 				((hva - vma->vm_start) >> PAGE_SHIFT);
407 			pgflags = pgprot_val(vma->vm_page_prot);
408 		}
409 		up_read(&current->mm->mmap_sem);
410 		if (!pfn)
411 			return -EFAULT;
412 	} else {
413 		page = pages[0];
414 		pfn = page_to_pfn(page);
415 		if (PageHuge(page)) {
416 			page = compound_head(page);
417 			pte_size <<= compound_order(page);
418 			/* See if we can insert a 2MB large-page PTE here */
419 			if (pte_size >= PMD_SIZE &&
420 			    (gpa & PMD_MASK & PAGE_MASK) ==
421 			    (hva & PMD_MASK & PAGE_MASK)) {
422 				level = 1;
423 				pfn &= ~((PMD_SIZE >> PAGE_SHIFT) - 1);
424 			}
425 		}
426 		/* See if we can provide write access */
427 		if (writing) {
428 			/*
429 			 * We assume gup_fast has set dirty on the host PTE.
430 			 */
431 			pgflags |= _PAGE_WRITE;
432 		} else {
433 			local_irq_save(flags);
434 			ptep = find_current_mm_pte(current->mm->pgd,
435 						   hva, NULL, NULL);
436 			if (ptep && pte_write(*ptep) && pte_dirty(*ptep))
437 				pgflags |= _PAGE_WRITE;
438 			local_irq_restore(flags);
439 		}
440 	}
441 
442 	/*
443 	 * Compute the PTE value that we need to insert.
444 	 */
445 	pgflags |= _PAGE_PRESENT | _PAGE_PTE | _PAGE_ACCESSED;
446 	if (pgflags & _PAGE_WRITE)
447 		pgflags |= _PAGE_DIRTY;
448 	pte = pfn_pte(pfn, __pgprot(pgflags));
449 
450 	/* Allocate space in the tree and write the PTE */
451 	ret = kvmppc_create_pte(kvm, pte, gpa, level, mmu_seq);
452 	if (ret == -EBUSY) {
453 		/*
454 		 * There's already a PMD where wanted to install a large page;
455 		 * for now, fall back to installing a small page.
456 		 */
457 		level = 0;
458 		pfn |= gfn & ((PMD_SIZE >> PAGE_SHIFT) - 1);
459 		pte = pfn_pte(pfn, __pgprot(pgflags));
460 		ret = kvmppc_create_pte(kvm, pte, gpa, level, mmu_seq);
461 	}
462 	if (ret == 0 || ret == -EAGAIN)
463 		ret = RESUME_GUEST;
464 
465 	if (page) {
466 		/*
467 		 * We drop pages[0] here, not page because page might
468 		 * have been set to the head page of a compound, but
469 		 * we have to drop the reference on the correct tail
470 		 * page to match the get inside gup()
471 		 */
472 		put_page(pages[0]);
473 	}
474 	return ret;
475 }
476 
477 /* Called with kvm->lock held */
478 int kvm_unmap_radix(struct kvm *kvm, struct kvm_memory_slot *memslot,
479 		    unsigned long gfn)
480 {
481 	pte_t *ptep;
482 	unsigned long gpa = gfn << PAGE_SHIFT;
483 	unsigned int shift;
484 	unsigned long old;
485 
486 	ptep = __find_linux_pte(kvm->arch.pgtable, gpa, NULL, &shift);
487 	if (ptep && pte_present(*ptep)) {
488 		old = kvmppc_radix_update_pte(kvm, ptep, _PAGE_PRESENT, 0,
489 					      gpa, shift);
490 		kvmppc_radix_tlbie_page(kvm, gpa, shift);
491 		if ((old & _PAGE_DIRTY) && memslot->dirty_bitmap) {
492 			unsigned long npages = 1;
493 			if (shift)
494 				npages = 1ul << (shift - PAGE_SHIFT);
495 			kvmppc_update_dirty_map(memslot, gfn, npages);
496 		}
497 	}
498 	return 0;
499 }
500 
501 /* Called with kvm->lock held */
502 int kvm_age_radix(struct kvm *kvm, struct kvm_memory_slot *memslot,
503 		  unsigned long gfn)
504 {
505 	pte_t *ptep;
506 	unsigned long gpa = gfn << PAGE_SHIFT;
507 	unsigned int shift;
508 	int ref = 0;
509 
510 	ptep = __find_linux_pte(kvm->arch.pgtable, gpa, NULL, &shift);
511 	if (ptep && pte_present(*ptep) && pte_young(*ptep)) {
512 		kvmppc_radix_update_pte(kvm, ptep, _PAGE_ACCESSED, 0,
513 					gpa, shift);
514 		/* XXX need to flush tlb here? */
515 		ref = 1;
516 	}
517 	return ref;
518 }
519 
520 /* Called with kvm->lock held */
521 int kvm_test_age_radix(struct kvm *kvm, struct kvm_memory_slot *memslot,
522 		       unsigned long gfn)
523 {
524 	pte_t *ptep;
525 	unsigned long gpa = gfn << PAGE_SHIFT;
526 	unsigned int shift;
527 	int ref = 0;
528 
529 	ptep = __find_linux_pte(kvm->arch.pgtable, gpa, NULL, &shift);
530 	if (ptep && pte_present(*ptep) && pte_young(*ptep))
531 		ref = 1;
532 	return ref;
533 }
534 
535 /* Returns the number of PAGE_SIZE pages that are dirty */
536 static int kvm_radix_test_clear_dirty(struct kvm *kvm,
537 				struct kvm_memory_slot *memslot, int pagenum)
538 {
539 	unsigned long gfn = memslot->base_gfn + pagenum;
540 	unsigned long gpa = gfn << PAGE_SHIFT;
541 	pte_t *ptep;
542 	unsigned int shift;
543 	int ret = 0;
544 
545 	ptep = __find_linux_pte(kvm->arch.pgtable, gpa, NULL, &shift);
546 	if (ptep && pte_present(*ptep) && pte_dirty(*ptep)) {
547 		ret = 1;
548 		if (shift)
549 			ret = 1 << (shift - PAGE_SHIFT);
550 		kvmppc_radix_update_pte(kvm, ptep, _PAGE_DIRTY, 0,
551 					gpa, shift);
552 		kvmppc_radix_tlbie_page(kvm, gpa, shift);
553 	}
554 	return ret;
555 }
556 
557 long kvmppc_hv_get_dirty_log_radix(struct kvm *kvm,
558 			struct kvm_memory_slot *memslot, unsigned long *map)
559 {
560 	unsigned long i, j;
561 	int npages;
562 
563 	for (i = 0; i < memslot->npages; i = j) {
564 		npages = kvm_radix_test_clear_dirty(kvm, memslot, i);
565 
566 		/*
567 		 * Note that if npages > 0 then i must be a multiple of npages,
568 		 * since huge pages are only used to back the guest at guest
569 		 * real addresses that are a multiple of their size.
570 		 * Since we have at most one PTE covering any given guest
571 		 * real address, if npages > 1 we can skip to i + npages.
572 		 */
573 		j = i + 1;
574 		if (npages) {
575 			set_dirty_bits(map, i, npages);
576 			i = j + npages;
577 		}
578 	}
579 	return 0;
580 }
581 
582 static void add_rmmu_ap_encoding(struct kvm_ppc_rmmu_info *info,
583 				 int psize, int *indexp)
584 {
585 	if (!mmu_psize_defs[psize].shift)
586 		return;
587 	info->ap_encodings[*indexp] = mmu_psize_defs[psize].shift |
588 		(mmu_psize_defs[psize].ap << 29);
589 	++(*indexp);
590 }
591 
592 int kvmhv_get_rmmu_info(struct kvm *kvm, struct kvm_ppc_rmmu_info *info)
593 {
594 	int i;
595 
596 	if (!radix_enabled())
597 		return -EINVAL;
598 	memset(info, 0, sizeof(*info));
599 
600 	/* 4k page size */
601 	info->geometries[0].page_shift = 12;
602 	info->geometries[0].level_bits[0] = 9;
603 	for (i = 1; i < 4; ++i)
604 		info->geometries[0].level_bits[i] = p9_supported_radix_bits[i];
605 	/* 64k page size */
606 	info->geometries[1].page_shift = 16;
607 	for (i = 0; i < 4; ++i)
608 		info->geometries[1].level_bits[i] = p9_supported_radix_bits[i];
609 
610 	i = 0;
611 	add_rmmu_ap_encoding(info, MMU_PAGE_4K, &i);
612 	add_rmmu_ap_encoding(info, MMU_PAGE_64K, &i);
613 	add_rmmu_ap_encoding(info, MMU_PAGE_2M, &i);
614 	add_rmmu_ap_encoding(info, MMU_PAGE_1G, &i);
615 
616 	return 0;
617 }
618 
619 int kvmppc_init_vm_radix(struct kvm *kvm)
620 {
621 	kvm->arch.pgtable = pgd_alloc(kvm->mm);
622 	if (!kvm->arch.pgtable)
623 		return -ENOMEM;
624 	return 0;
625 }
626 
627 void kvmppc_free_radix(struct kvm *kvm)
628 {
629 	unsigned long ig, iu, im;
630 	pte_t *pte;
631 	pmd_t *pmd;
632 	pud_t *pud;
633 	pgd_t *pgd;
634 
635 	if (!kvm->arch.pgtable)
636 		return;
637 	pgd = kvm->arch.pgtable;
638 	for (ig = 0; ig < PTRS_PER_PGD; ++ig, ++pgd) {
639 		if (!pgd_present(*pgd))
640 			continue;
641 		pud = pud_offset(pgd, 0);
642 		for (iu = 0; iu < PTRS_PER_PUD; ++iu, ++pud) {
643 			if (!pud_present(*pud))
644 				continue;
645 			pmd = pmd_offset(pud, 0);
646 			for (im = 0; im < PTRS_PER_PMD; ++im, ++pmd) {
647 				if (pmd_huge(*pmd)) {
648 					pmd_clear(pmd);
649 					continue;
650 				}
651 				if (!pmd_present(*pmd))
652 					continue;
653 				pte = pte_offset_map(pmd, 0);
654 				memset(pte, 0, sizeof(long) << PTE_INDEX_SIZE);
655 				kvmppc_pte_free(pte);
656 				pmd_clear(pmd);
657 			}
658 			pmd_free(kvm->mm, pmd_offset(pud, 0));
659 			pud_clear(pud);
660 		}
661 		pud_free(kvm->mm, pud_offset(pgd, 0));
662 		pgd_clear(pgd);
663 	}
664 	pgd_free(kvm->mm, kvm->arch.pgtable);
665 	kvm->arch.pgtable = NULL;
666 }
667 
668 static void pte_ctor(void *addr)
669 {
670 	memset(addr, 0, PTE_TABLE_SIZE);
671 }
672 
673 int kvmppc_radix_init(void)
674 {
675 	unsigned long size = sizeof(void *) << PTE_INDEX_SIZE;
676 
677 	kvm_pte_cache = kmem_cache_create("kvm-pte", size, size, 0, pte_ctor);
678 	if (!kvm_pte_cache)
679 		return -ENOMEM;
680 	return 0;
681 }
682 
683 void kvmppc_radix_exit(void)
684 {
685 	kmem_cache_destroy(kvm_pte_cache);
686 }
687