1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 *
4 * Copyright 2010 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com>
5 * Copyright 2011 David Gibson, IBM Corporation <dwg@au1.ibm.com>
6 * Copyright 2016 Alexey Kardashevskiy, IBM Corporation <aik@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#include <linux/highmem.h>
14#include <linux/gfp.h>
15#include <linux/slab.h>
16#include <linux/sched/signal.h>
17#include <linux/hugetlb.h>
18#include <linux/list.h>
19#include <linux/anon_inodes.h>
20#include <linux/iommu.h>
21#include <linux/file.h>
22#include <linux/mm.h>
23
24#include <asm/kvm_ppc.h>
25#include <asm/kvm_book3s.h>
26#include <asm/book3s/64/mmu-hash.h>
27#include <asm/hvcall.h>
28#include <asm/synch.h>
29#include <asm/ppc-opcode.h>
30#include <asm/udbg.h>
31#include <asm/iommu.h>
32#include <asm/tce.h>
33#include <asm/mmu_context.h>
34
35static struct kvmppc_spapr_tce_table *kvmppc_find_table(struct kvm *kvm,
36	unsigned long liobn)
37{
38	struct kvmppc_spapr_tce_table *stt;
39
40	list_for_each_entry_lockless(stt, &kvm->arch.spapr_tce_tables, list)
41		if (stt->liobn == liobn)
42			return stt;
43
44	return NULL;
45}
46
47static unsigned long kvmppc_tce_pages(unsigned long iommu_pages)
48{
49	return ALIGN(iommu_pages * sizeof(u64), PAGE_SIZE) / PAGE_SIZE;
50}
51
52static unsigned long kvmppc_stt_pages(unsigned long tce_pages)
53{
54	unsigned long stt_bytes = sizeof(struct kvmppc_spapr_tce_table) +
55			(tce_pages * sizeof(struct page *));
56
57	return tce_pages + ALIGN(stt_bytes, PAGE_SIZE) / PAGE_SIZE;
58}
59
60static void kvm_spapr_tce_iommu_table_free(struct rcu_head *head)
61{
62	struct kvmppc_spapr_tce_iommu_table *stit = container_of(head,
63			struct kvmppc_spapr_tce_iommu_table, rcu);
64
65	iommu_tce_table_put(stit->tbl);
66
67	kfree(stit);
68}
69
70static void kvm_spapr_tce_liobn_put(struct kref *kref)
71{
72	struct kvmppc_spapr_tce_iommu_table *stit = container_of(kref,
73			struct kvmppc_spapr_tce_iommu_table, kref);
74
75	list_del_rcu(&stit->next);
76
77	call_rcu(&stit->rcu, kvm_spapr_tce_iommu_table_free);
78}
79
80extern void kvm_spapr_tce_release_iommu_group(struct kvm *kvm,
81		struct iommu_group *grp)
82{
83	int i;
84	struct kvmppc_spapr_tce_table *stt;
85	struct kvmppc_spapr_tce_iommu_table *stit, *tmp;
86	struct iommu_table_group *table_group = NULL;
87
88	rcu_read_lock();
89	list_for_each_entry_rcu(stt, &kvm->arch.spapr_tce_tables, list) {
90
91		table_group = iommu_group_get_iommudata(grp);
92		if (WARN_ON(!table_group))
93			continue;
94
95		list_for_each_entry_safe(stit, tmp, &stt->iommu_tables, next) {
96			for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) {
97				if (table_group->tables[i] != stit->tbl)
98					continue;
99
100				kref_put(&stit->kref, kvm_spapr_tce_liobn_put);
101			}
102		}
103		cond_resched_rcu();
104	}
105	rcu_read_unlock();
106}
107
108extern long kvm_spapr_tce_attach_iommu_group(struct kvm *kvm, int tablefd,
109		struct iommu_group *grp)
110{
111	struct kvmppc_spapr_tce_table *stt = NULL;
112	bool found = false;
113	struct iommu_table *tbl = NULL;
114	struct iommu_table_group *table_group;
115	long i;
116	struct kvmppc_spapr_tce_iommu_table *stit;
117	struct fd f;
118
119	f = fdget(tablefd);
120	if (!f.file)
121		return -EBADF;
122
123	rcu_read_lock();
124	list_for_each_entry_rcu(stt, &kvm->arch.spapr_tce_tables, list) {
125		if (stt == f.file->private_data) {
126			found = true;
127			break;
128		}
129	}
130	rcu_read_unlock();
131
132	fdput(f);
133
134	if (!found)
135		return -EINVAL;
136
137	table_group = iommu_group_get_iommudata(grp);
138	if (WARN_ON(!table_group))
139		return -EFAULT;
140
141	for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) {
142		struct iommu_table *tbltmp = table_group->tables[i];
143
144		if (!tbltmp)
145			continue;
146		/* Make sure hardware table parameters are compatible */
147		if ((tbltmp->it_page_shift <= stt->page_shift) &&
148				(tbltmp->it_offset << tbltmp->it_page_shift ==
149				 stt->offset << stt->page_shift) &&
150				(tbltmp->it_size << tbltmp->it_page_shift >=
151				 stt->size << stt->page_shift)) {
152			/*
153			 * Reference the table to avoid races with
154			 * add/remove DMA windows.
155			 */
156			tbl = iommu_tce_table_get(tbltmp);
157			break;
158		}
159	}
160	if (!tbl)
161		return -EINVAL;
162
163	rcu_read_lock();
164	list_for_each_entry_rcu(stit, &stt->iommu_tables, next) {
165		if (tbl != stit->tbl)
166			continue;
167
168		if (!kref_get_unless_zero(&stit->kref)) {
169			/* stit is being destroyed */
170			iommu_tce_table_put(tbl);
171			rcu_read_unlock();
172			return -ENOTTY;
173		}
174		/*
175		 * The table is already known to this KVM, we just increased
176		 * its KVM reference counter and can return.
177		 */
178		rcu_read_unlock();
179		return 0;
180	}
181	rcu_read_unlock();
182
183	stit = kzalloc(sizeof(*stit), GFP_KERNEL);
184	if (!stit) {
185		iommu_tce_table_put(tbl);
186		return -ENOMEM;
187	}
188
189	stit->tbl = tbl;
190	kref_init(&stit->kref);
191
192	list_add_rcu(&stit->next, &stt->iommu_tables);
193
194	return 0;
195}
196
197static void release_spapr_tce_table(struct rcu_head *head)
198{
199	struct kvmppc_spapr_tce_table *stt = container_of(head,
200			struct kvmppc_spapr_tce_table, rcu);
201	unsigned long i, npages = kvmppc_tce_pages(stt->size);
202
203	for (i = 0; i < npages; i++)
204		if (stt->pages[i])
205			__free_page(stt->pages[i]);
206
207	kfree(stt);
208}
209
210static struct page *kvm_spapr_get_tce_page(struct kvmppc_spapr_tce_table *stt,
211		unsigned long sttpage)
212{
213	struct page *page = stt->pages[sttpage];
214
215	if (page)
216		return page;
217
218	mutex_lock(&stt->alloc_lock);
219	page = stt->pages[sttpage];
220	if (!page) {
221		page = alloc_page(GFP_KERNEL | __GFP_ZERO);
222		WARN_ON_ONCE(!page);
223		if (page)
224			stt->pages[sttpage] = page;
225	}
226	mutex_unlock(&stt->alloc_lock);
227
228	return page;
229}
230
231static vm_fault_t kvm_spapr_tce_fault(struct vm_fault *vmf)
232{
233	struct kvmppc_spapr_tce_table *stt = vmf->vma->vm_file->private_data;
234	struct page *page;
235
236	if (vmf->pgoff >= kvmppc_tce_pages(stt->size))
237		return VM_FAULT_SIGBUS;
238
239	page = kvm_spapr_get_tce_page(stt, vmf->pgoff);
240	if (!page)
241		return VM_FAULT_OOM;
242
243	get_page(page);
244	vmf->page = page;
245	return 0;
246}
247
248static const struct vm_operations_struct kvm_spapr_tce_vm_ops = {
249	.fault = kvm_spapr_tce_fault,
250};
251
252static int kvm_spapr_tce_mmap(struct file *file, struct vm_area_struct *vma)
253{
254	vma->vm_ops = &kvm_spapr_tce_vm_ops;
255	return 0;
256}
257
258static int kvm_spapr_tce_release(struct inode *inode, struct file *filp)
259{
260	struct kvmppc_spapr_tce_table *stt = filp->private_data;
261	struct kvmppc_spapr_tce_iommu_table *stit, *tmp;
262	struct kvm *kvm = stt->kvm;
263
264	mutex_lock(&kvm->lock);
265	list_del_rcu(&stt->list);
266	mutex_unlock(&kvm->lock);
267
268	list_for_each_entry_safe(stit, tmp, &stt->iommu_tables, next) {
269		WARN_ON(!kref_read(&stit->kref));
270		while (1) {
271			if (kref_put(&stit->kref, kvm_spapr_tce_liobn_put))
272				break;
273		}
274	}
275
276	account_locked_vm(kvm->mm,
277		kvmppc_stt_pages(kvmppc_tce_pages(stt->size)), false);
278
279	kvm_put_kvm(stt->kvm);
280
281	call_rcu(&stt->rcu, release_spapr_tce_table);
282
283	return 0;
284}
285
286static const struct file_operations kvm_spapr_tce_fops = {
287	.mmap           = kvm_spapr_tce_mmap,
288	.release	= kvm_spapr_tce_release,
289};
290
291int kvm_vm_ioctl_create_spapr_tce(struct kvm *kvm,
292				  struct kvm_create_spapr_tce_64 *args)
293{
294	struct kvmppc_spapr_tce_table *stt = NULL;
295	struct kvmppc_spapr_tce_table *siter;
296	struct mm_struct *mm = kvm->mm;
297	unsigned long npages;
298	int ret;
299
300	if (!args->size || args->page_shift < 12 || args->page_shift > 34 ||
301		(args->offset + args->size > (ULLONG_MAX >> args->page_shift)))
302		return -EINVAL;
303
304	npages = kvmppc_tce_pages(args->size);
305	ret = account_locked_vm(mm, kvmppc_stt_pages(npages), true);
306	if (ret)
307		return ret;
308
309	ret = -ENOMEM;
310	stt = kzalloc(struct_size(stt, pages, npages), GFP_KERNEL | __GFP_NOWARN);
311	if (!stt)
312		goto fail_acct;
313
314	stt->liobn = args->liobn;
315	stt->page_shift = args->page_shift;
316	stt->offset = args->offset;
317	stt->size = args->size;
318	stt->kvm = kvm;
319	mutex_init(&stt->alloc_lock);
320	INIT_LIST_HEAD_RCU(&stt->iommu_tables);
321
322	mutex_lock(&kvm->lock);
323
324	/* Check this LIOBN hasn't been previously allocated */
325	ret = 0;
326	list_for_each_entry(siter, &kvm->arch.spapr_tce_tables, list) {
327		if (siter->liobn == args->liobn) {
328			ret = -EBUSY;
329			break;
330		}
331	}
332
333	kvm_get_kvm(kvm);
334	if (!ret)
335		ret = anon_inode_getfd("kvm-spapr-tce", &kvm_spapr_tce_fops,
336				       stt, O_RDWR | O_CLOEXEC);
337
338	if (ret >= 0)
339		list_add_rcu(&stt->list, &kvm->arch.spapr_tce_tables);
340	else
341		kvm_put_kvm_no_destroy(kvm);
342
343	mutex_unlock(&kvm->lock);
344
345	if (ret >= 0)
346		return ret;
347
348	kfree(stt);
349 fail_acct:
350	account_locked_vm(mm, kvmppc_stt_pages(npages), false);
351	return ret;
352}
353
354static long kvmppc_tce_to_ua(struct kvm *kvm, unsigned long tce,
355		unsigned long *ua)
356{
357	unsigned long gfn = tce >> PAGE_SHIFT;
358	struct kvm_memory_slot *memslot;
359
360	memslot = __gfn_to_memslot(kvm_memslots(kvm), gfn);
361	if (!memslot)
362		return -EINVAL;
363
364	*ua = __gfn_to_hva_memslot(memslot, gfn) |
365		(tce & ~(PAGE_MASK | TCE_PCI_READ | TCE_PCI_WRITE));
366
367	return 0;
368}
369
370static long kvmppc_tce_validate(struct kvmppc_spapr_tce_table *stt,
371		unsigned long tce)
372{
373	unsigned long gpa = tce & ~(TCE_PCI_READ | TCE_PCI_WRITE);
374	enum dma_data_direction dir = iommu_tce_direction(tce);
375	struct kvmppc_spapr_tce_iommu_table *stit;
376	unsigned long ua = 0;
377
378	/* Allow userspace to poison TCE table */
379	if (dir == DMA_NONE)
380		return H_SUCCESS;
381
382	if (iommu_tce_check_gpa(stt->page_shift, gpa))
383		return H_TOO_HARD;
384
385	if (kvmppc_tce_to_ua(stt->kvm, tce, &ua))
386		return H_TOO_HARD;
387
388	rcu_read_lock();
389	list_for_each_entry_rcu(stit, &stt->iommu_tables, next) {
390		unsigned long hpa = 0;
391		struct mm_iommu_table_group_mem_t *mem;
392		long shift = stit->tbl->it_page_shift;
393
394		mem = mm_iommu_lookup(stt->kvm->mm, ua, 1ULL << shift);
395		if (!mem || mm_iommu_ua_to_hpa(mem, ua, shift, &hpa)) {
396			rcu_read_unlock();
397			return H_TOO_HARD;
398		}
399	}
400	rcu_read_unlock();
401
402	return H_SUCCESS;
403}
404
405/*
406 * Handles TCE requests for emulated devices.
407 * Puts guest TCE values to the table and expects user space to convert them.
408 * Cannot fail so kvmppc_tce_validate must be called before it.
409 */
410static void kvmppc_tce_put(struct kvmppc_spapr_tce_table *stt,
411		unsigned long idx, unsigned long tce)
412{
413	struct page *page;
414	u64 *tbl;
415	unsigned long sttpage;
416
417	idx -= stt->offset;
418	sttpage = idx / TCES_PER_PAGE;
419	page = stt->pages[sttpage];
420
421	if (!page) {
422		/* We allow any TCE, not just with read|write permissions */
423		if (!tce)
424			return;
425
426		page = kvm_spapr_get_tce_page(stt, sttpage);
427		if (!page)
428			return;
429	}
430	tbl = page_to_virt(page);
431
432	tbl[idx % TCES_PER_PAGE] = tce;
433}
434
435static void kvmppc_clear_tce(struct mm_struct *mm, struct kvmppc_spapr_tce_table *stt,
436		struct iommu_table *tbl, unsigned long entry)
437{
438	unsigned long i;
439	unsigned long subpages = 1ULL << (stt->page_shift - tbl->it_page_shift);
440	unsigned long io_entry = entry << (stt->page_shift - tbl->it_page_shift);
441
442	for (i = 0; i < subpages; ++i) {
443		unsigned long hpa = 0;
444		enum dma_data_direction dir = DMA_NONE;
445
446		iommu_tce_xchg_no_kill(mm, tbl, io_entry + i, &hpa, &dir);
447	}
448}
449
450static long kvmppc_tce_iommu_mapped_dec(struct kvm *kvm,
451		struct iommu_table *tbl, unsigned long entry)
452{
453	struct mm_iommu_table_group_mem_t *mem = NULL;
454	const unsigned long pgsize = 1ULL << tbl->it_page_shift;
455	__be64 *pua = IOMMU_TABLE_USERSPACE_ENTRY_RO(tbl, entry);
456
457	if (!pua)
458		return H_SUCCESS;
459
460	mem = mm_iommu_lookup(kvm->mm, be64_to_cpu(*pua), pgsize);
461	if (!mem)
462		return H_TOO_HARD;
463
464	mm_iommu_mapped_dec(mem);
465
466	*pua = cpu_to_be64(0);
467
468	return H_SUCCESS;
469}
470
471static long kvmppc_tce_iommu_do_unmap(struct kvm *kvm,
472		struct iommu_table *tbl, unsigned long entry)
473{
474	enum dma_data_direction dir = DMA_NONE;
475	unsigned long hpa = 0;
476	long ret;
477
478	if (WARN_ON_ONCE(iommu_tce_xchg_no_kill(kvm->mm, tbl, entry, &hpa,
479					&dir)))
480		return H_TOO_HARD;
481
482	if (dir == DMA_NONE)
483		return H_SUCCESS;
484
485	ret = kvmppc_tce_iommu_mapped_dec(kvm, tbl, entry);
486	if (ret != H_SUCCESS)
487		iommu_tce_xchg_no_kill(kvm->mm, tbl, entry, &hpa, &dir);
488
489	return ret;
490}
491
492static long kvmppc_tce_iommu_unmap(struct kvm *kvm,
493		struct kvmppc_spapr_tce_table *stt, struct iommu_table *tbl,
494		unsigned long entry)
495{
496	unsigned long i, ret = H_SUCCESS;
497	unsigned long subpages = 1ULL << (stt->page_shift - tbl->it_page_shift);
498	unsigned long io_entry = entry * subpages;
499
500	for (i = 0; i < subpages; ++i) {
501		ret = kvmppc_tce_iommu_do_unmap(kvm, tbl, io_entry + i);
502		if (ret != H_SUCCESS)
503			break;
504	}
505
506	iommu_tce_kill(tbl, io_entry, subpages);
507
508	return ret;
509}
510
511static long kvmppc_tce_iommu_do_map(struct kvm *kvm, struct iommu_table *tbl,
512		unsigned long entry, unsigned long ua,
513		enum dma_data_direction dir)
514{
515	long ret;
516	unsigned long hpa;
517	__be64 *pua = IOMMU_TABLE_USERSPACE_ENTRY(tbl, entry);
518	struct mm_iommu_table_group_mem_t *mem;
519
520	if (!pua)
521		/* it_userspace allocation might be delayed */
522		return H_TOO_HARD;
523
524	mem = mm_iommu_lookup(kvm->mm, ua, 1ULL << tbl->it_page_shift);
525	if (!mem)
526		/* This only handles v2 IOMMU type, v1 is handled via ioctl() */
527		return H_TOO_HARD;
528
529	if (WARN_ON_ONCE(mm_iommu_ua_to_hpa(mem, ua, tbl->it_page_shift, &hpa)))
530		return H_TOO_HARD;
531
532	if (mm_iommu_mapped_inc(mem))
533		return H_TOO_HARD;
534
535	ret = iommu_tce_xchg_no_kill(kvm->mm, tbl, entry, &hpa, &dir);
536	if (WARN_ON_ONCE(ret)) {
537		mm_iommu_mapped_dec(mem);
538		return H_TOO_HARD;
539	}
540
541	if (dir != DMA_NONE)
542		kvmppc_tce_iommu_mapped_dec(kvm, tbl, entry);
543
544	*pua = cpu_to_be64(ua);
545
546	return 0;
547}
548
549static long kvmppc_tce_iommu_map(struct kvm *kvm,
550		struct kvmppc_spapr_tce_table *stt, struct iommu_table *tbl,
551		unsigned long entry, unsigned long ua,
552		enum dma_data_direction dir)
553{
554	unsigned long i, pgoff, ret = H_SUCCESS;
555	unsigned long subpages = 1ULL << (stt->page_shift - tbl->it_page_shift);
556	unsigned long io_entry = entry * subpages;
557
558	for (i = 0, pgoff = 0; i < subpages;
559			++i, pgoff += IOMMU_PAGE_SIZE(tbl)) {
560
561		ret = kvmppc_tce_iommu_do_map(kvm, tbl,
562				io_entry + i, ua + pgoff, dir);
563		if (ret != H_SUCCESS)
564			break;
565	}
566
567	iommu_tce_kill(tbl, io_entry, subpages);
568
569	return ret;
570}
571
572long kvmppc_h_put_tce(struct kvm_vcpu *vcpu, unsigned long liobn,
573		      unsigned long ioba, unsigned long tce)
574{
575	struct kvmppc_spapr_tce_table *stt;
576	long ret, idx;
577	struct kvmppc_spapr_tce_iommu_table *stit;
578	unsigned long entry, ua = 0;
579	enum dma_data_direction dir;
580
581	/* udbg_printf("H_PUT_TCE(): liobn=0x%lx ioba=0x%lx, tce=0x%lx\n", */
582	/* 	    liobn, ioba, tce); */
583
584	stt = kvmppc_find_table(vcpu->kvm, liobn);
585	if (!stt)
586		return H_TOO_HARD;
587
588	ret = kvmppc_ioba_validate(stt, ioba, 1);
589	if (ret != H_SUCCESS)
590		return ret;
591
592	idx = srcu_read_lock(&vcpu->kvm->srcu);
593
594	ret = kvmppc_tce_validate(stt, tce);
595	if (ret != H_SUCCESS)
596		goto unlock_exit;
597
598	dir = iommu_tce_direction(tce);
599
600	if ((dir != DMA_NONE) && kvmppc_tce_to_ua(vcpu->kvm, tce, &ua)) {
601		ret = H_PARAMETER;
602		goto unlock_exit;
603	}
604
605	entry = ioba >> stt->page_shift;
606
607	list_for_each_entry_lockless(stit, &stt->iommu_tables, next) {
608		if (dir == DMA_NONE)
609			ret = kvmppc_tce_iommu_unmap(vcpu->kvm, stt,
610					stit->tbl, entry);
611		else
612			ret = kvmppc_tce_iommu_map(vcpu->kvm, stt, stit->tbl,
613					entry, ua, dir);
614
615
616		if (ret != H_SUCCESS) {
617			kvmppc_clear_tce(vcpu->kvm->mm, stt, stit->tbl, entry);
618			goto unlock_exit;
619		}
620	}
621
622	kvmppc_tce_put(stt, entry, tce);
623
624unlock_exit:
625	srcu_read_unlock(&vcpu->kvm->srcu, idx);
626
627	return ret;
628}
629EXPORT_SYMBOL_GPL(kvmppc_h_put_tce);
630
631long kvmppc_h_put_tce_indirect(struct kvm_vcpu *vcpu,
632		unsigned long liobn, unsigned long ioba,
633		unsigned long tce_list, unsigned long npages)
634{
635	struct kvmppc_spapr_tce_table *stt;
636	long i, ret = H_SUCCESS, idx;
637	unsigned long entry, ua = 0;
638	u64 __user *tces;
639	u64 tce;
640	struct kvmppc_spapr_tce_iommu_table *stit;
641
642	stt = kvmppc_find_table(vcpu->kvm, liobn);
643	if (!stt)
644		return H_TOO_HARD;
645
646	entry = ioba >> stt->page_shift;
647	/*
648	 * SPAPR spec says that the maximum size of the list is 512 TCEs
649	 * so the whole table fits in 4K page
650	 */
651	if (npages > 512)
652		return H_PARAMETER;
653
654	if (tce_list & (SZ_4K - 1))
655		return H_PARAMETER;
656
657	ret = kvmppc_ioba_validate(stt, ioba, npages);
658	if (ret != H_SUCCESS)
659		return ret;
660
661	idx = srcu_read_lock(&vcpu->kvm->srcu);
662	if (kvmppc_tce_to_ua(vcpu->kvm, tce_list, &ua)) {
663		ret = H_TOO_HARD;
664		goto unlock_exit;
665	}
666	tces = (u64 __user *) ua;
667
668	for (i = 0; i < npages; ++i) {
669		if (get_user(tce, tces + i)) {
670			ret = H_TOO_HARD;
671			goto unlock_exit;
672		}
673		tce = be64_to_cpu(tce);
674
675		ret = kvmppc_tce_validate(stt, tce);
676		if (ret != H_SUCCESS)
677			goto unlock_exit;
678	}
679
680	for (i = 0; i < npages; ++i) {
681		/*
682		 * This looks unsafe, because we validate, then regrab
683		 * the TCE from userspace which could have been changed by
684		 * another thread.
685		 *
686		 * But it actually is safe, because the relevant checks will be
687		 * re-executed in the following code.  If userspace tries to
688		 * change this dodgily it will result in a messier failure mode
689		 * but won't threaten the host.
690		 */
691		if (get_user(tce, tces + i)) {
692			ret = H_TOO_HARD;
693			goto unlock_exit;
694		}
695		tce = be64_to_cpu(tce);
696
697		if (kvmppc_tce_to_ua(vcpu->kvm, tce, &ua)) {
698			ret = H_PARAMETER;
699			goto unlock_exit;
700		}
701
702		list_for_each_entry_lockless(stit, &stt->iommu_tables, next) {
703			ret = kvmppc_tce_iommu_map(vcpu->kvm, stt,
704					stit->tbl, entry + i, ua,
705					iommu_tce_direction(tce));
706
707			if (ret != H_SUCCESS) {
708				kvmppc_clear_tce(vcpu->kvm->mm, stt, stit->tbl,
709						 entry + i);
710				goto unlock_exit;
711			}
712		}
713
714		kvmppc_tce_put(stt, entry + i, tce);
715	}
716
717unlock_exit:
718	srcu_read_unlock(&vcpu->kvm->srcu, idx);
719
720	return ret;
721}
722EXPORT_SYMBOL_GPL(kvmppc_h_put_tce_indirect);
723
724long kvmppc_h_stuff_tce(struct kvm_vcpu *vcpu,
725		unsigned long liobn, unsigned long ioba,
726		unsigned long tce_value, unsigned long npages)
727{
728	struct kvmppc_spapr_tce_table *stt;
729	long i, ret;
730	struct kvmppc_spapr_tce_iommu_table *stit;
731
732	stt = kvmppc_find_table(vcpu->kvm, liobn);
733	if (!stt)
734		return H_TOO_HARD;
735
736	ret = kvmppc_ioba_validate(stt, ioba, npages);
737	if (ret != H_SUCCESS)
738		return ret;
739
740	/* Check permission bits only to allow userspace poison TCE for debug */
741	if (tce_value & (TCE_PCI_WRITE | TCE_PCI_READ))
742		return H_PARAMETER;
743
744	list_for_each_entry_lockless(stit, &stt->iommu_tables, next) {
745		unsigned long entry = ioba >> stt->page_shift;
746
747		for (i = 0; i < npages; ++i) {
748			ret = kvmppc_tce_iommu_unmap(vcpu->kvm, stt,
749					stit->tbl, entry + i);
750
751			if (ret == H_SUCCESS)
752				continue;
753
754			if (ret == H_TOO_HARD)
755				return ret;
756
757			WARN_ON_ONCE(1);
758			kvmppc_clear_tce(vcpu->kvm->mm, stt, stit->tbl, entry + i);
759		}
760	}
761
762	for (i = 0; i < npages; ++i, ioba += (1ULL << stt->page_shift))
763		kvmppc_tce_put(stt, ioba >> stt->page_shift, tce_value);
764
765	return ret;
766}
767EXPORT_SYMBOL_GPL(kvmppc_h_stuff_tce);
768
769long kvmppc_h_get_tce(struct kvm_vcpu *vcpu, unsigned long liobn,
770		      unsigned long ioba)
771{
772	struct kvmppc_spapr_tce_table *stt;
773	long ret;
774	unsigned long idx;
775	struct page *page;
776	u64 *tbl;
777
778	stt = kvmppc_find_table(vcpu->kvm, liobn);
779	if (!stt)
780		return H_TOO_HARD;
781
782	ret = kvmppc_ioba_validate(stt, ioba, 1);
783	if (ret != H_SUCCESS)
784		return ret;
785
786	idx = (ioba >> stt->page_shift) - stt->offset;
787	page = stt->pages[idx / TCES_PER_PAGE];
788	if (!page) {
789		vcpu->arch.regs.gpr[4] = 0;
790		return H_SUCCESS;
791	}
792	tbl = (u64 *)page_address(page);
793
794	vcpu->arch.regs.gpr[4] = tbl[idx % TCES_PER_PAGE];
795
796	return H_SUCCESS;
797}
798EXPORT_SYMBOL_GPL(kvmppc_h_get_tce);
799