[mirror_ubuntu-zesty-kernel.git] / arch / powerpc / kvm / book3s_64_vio_hv.c

/*
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License, version 2, as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 *
 * Copyright 2010 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com>
 * Copyright 2011 David Gibson, IBM Corporation <dwg@au1.ibm.com>
 * Copyright 2016 Alexey Kardashevskiy, IBM Corporation <aik@au1.ibm.com>
 */

#include <linux/types.h>
#include <linux/string.h>
#include <linux/kvm.h>
#include <linux/kvm_host.h>
#include <linux/highmem.h>
#include <linux/gfp.h>
#include <linux/slab.h>
#include <linux/hugetlb.h>
#include <linux/list.h>

#include <asm/tlbflush.h>
#include <asm/kvm_ppc.h>
#include <asm/kvm_book3s.h>
#include <asm/book3s/64/mmu-hash.h>
#include <asm/mmu_context.h>
#include <asm/hvcall.h>
#include <asm/synch.h>
#include <asm/ppc-opcode.h>
#include <asm/kvm_host.h>
#include <asm/udbg.h>
#include <asm/iommu.h>
#include <asm/tce.h>

#ifdef CONFIG_BUG

#define WARN_ON_ONCE_RM(condition)	({			\
	static bool __section(.data.unlikely) __warned;		\
	int __ret_warn_once = !!(condition);			\
								\
	if (unlikely(__ret_warn_once && !__warned)) {		\
		__warned = true;				\
		pr_err("WARN_ON_ONCE_RM: (%s) at %s:%u\n",	\
				__stringify(condition),		\
				__func__, __LINE__);		\
		dump_stack();					\
	}							\
	unlikely(__ret_warn_once);				\
})

#else

#define WARN_ON_ONCE_RM(condition) ({				\
	int __ret_warn_on = !!(condition);			\
	unlikely(__ret_warn_on);				\
})

#endif

#define TCES_PER_PAGE	(PAGE_SIZE / sizeof(u64))

/*
 * Finds a TCE table descriptor by LIOBN.
 *
 * WARNING: This will be called in real or virtual mode on HV KVM and virtual
 *          mode on PR KVM
 */
struct kvmppc_spapr_tce_table *kvmppc_find_table(struct kvm *kvm,
		unsigned long liobn)
{
	struct kvmppc_spapr_tce_table *stt;

	list_for_each_entry_lockless(stt, &kvm->arch.spapr_tce_tables, list)
		if (stt->liobn == liobn)
			return stt;

	return NULL;
}
EXPORT_SYMBOL_GPL(kvmppc_find_table);

/*
 * Validates IO address.
 *
 * WARNING: This will be called in real-mode on HV KVM and virtual
 *          mode on PR KVM
 */
long kvmppc_ioba_validate(struct kvmppc_spapr_tce_table *stt,
		unsigned long ioba, unsigned long npages)
{
	unsigned long mask = (1ULL << stt->page_shift) - 1;
	unsigned long idx = ioba >> stt->page_shift;

	if ((ioba & mask) || (idx < stt->offset) ||
			(idx - stt->offset + npages > stt->size) ||
			(idx + npages < idx))
		return H_PARAMETER;

	return H_SUCCESS;
}
EXPORT_SYMBOL_GPL(kvmppc_ioba_validate);

/*
 * Validates TCE address.
 * At the moment flags and page mask are validated.
 * As the host kernel does not access those addresses (just puts them
 * to the table and user space is supposed to process them), we can skip
 * checking other things (such as TCE is a guest RAM address or the page
 * was actually allocated).
 *
 * WARNING: This will be called in real-mode on HV KVM and virtual
 *          mode on PR KVM
 */
long kvmppc_tce_validate(struct kvmppc_spapr_tce_table *stt, unsigned long tce)
{
	unsigned long page_mask = ~((1ULL << stt->page_shift) - 1);
	unsigned long mask = ~(page_mask | TCE_PCI_WRITE | TCE_PCI_READ);

	if (tce & mask)
		return H_PARAMETER;

	return H_SUCCESS;
}
EXPORT_SYMBOL_GPL(kvmppc_tce_validate);

/* Note on the use of page_address() in real mode,
 *
 * It is safe to use page_address() in real mode on ppc64 because
 * page_address() is always defined as lowmem_page_address()
 * which returns __va(PFN_PHYS(page_to_pfn(page))) which is arithmetic
 * operation and does not access page struct.
 *
 * Theoretically page_address() could be defined different
 * but either WANT_PAGE_VIRTUAL or HASHED_PAGE_VIRTUAL
 * would have to be enabled.
 * WANT_PAGE_VIRTUAL is never enabled on ppc32/ppc64,
 * HASHED_PAGE_VIRTUAL could be enabled for ppc32 only and only
 * if CONFIG_HIGHMEM is defined. As CONFIG_SPARSEMEM_VMEMMAP
 * is not expected to be enabled on ppc32, page_address()
 * is safe for ppc32 as well.
 *
 * WARNING: This will be called in real-mode on HV KVM and virtual
 *          mode on PR KVM
 */
static u64 *kvmppc_page_address(struct page *page)
{
#if defined(HASHED_PAGE_VIRTUAL) || defined(WANT_PAGE_VIRTUAL)
#error TODO: fix to avoid page_address() here
#endif
	return (u64 *) page_address(page);
}

/*
 * Handles TCE requests for emulated devices.
 * Puts guest TCE values to the table and expects user space to convert them.
 * Called in both real and virtual modes.
 * Cannot fail so kvmppc_tce_validate must be called before it.
 *
 * WARNING: This will be called in real-mode on HV KVM and virtual
 *          mode on PR KVM
 */
void kvmppc_tce_put(struct kvmppc_spapr_tce_table *stt,
		unsigned long idx, unsigned long tce)
{
	struct page *page;
	u64 *tbl;

	idx -= stt->offset;
	page = stt->pages[idx / TCES_PER_PAGE];
	tbl = kvmppc_page_address(page);

	tbl[idx % TCES_PER_PAGE] = tce;
}
EXPORT_SYMBOL_GPL(kvmppc_tce_put);

long kvmppc_gpa_to_ua(struct kvm *kvm, unsigned long gpa,
		unsigned long *ua, unsigned long **prmap)
{
	unsigned long gfn = gpa >> PAGE_SHIFT;
	struct kvm_memory_slot *memslot;

	memslot = search_memslots(kvm_memslots(kvm), gfn);
	if (!memslot)
		return -EINVAL;

	*ua = __gfn_to_hva_memslot(memslot, gfn) |
		(gpa & ~(PAGE_MASK | TCE_PCI_READ | TCE_PCI_WRITE));

#ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
	if (prmap)
		*prmap = &memslot->arch.rmap[gfn - memslot->base_gfn];
#endif

	return 0;
}
EXPORT_SYMBOL_GPL(kvmppc_gpa_to_ua);

#ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
static void kvmppc_rm_clear_tce(struct iommu_table *tbl, unsigned long entry)
{
	unsigned long hpa = 0;
	enum dma_data_direction dir = DMA_NONE;

	iommu_tce_xchg_rm(tbl, entry, &hpa, &dir);
}

static long kvmppc_rm_tce_iommu_mapped_dec(struct kvm *kvm,
		struct iommu_table *tbl, unsigned long entry)
{
	struct mm_iommu_table_group_mem_t *mem = NULL;
	const unsigned long pgsize = 1ULL << tbl->it_page_shift;
	unsigned long *pua = IOMMU_TABLE_USERSPACE_ENTRY(tbl, entry);

	if (!pua)
		/* it_userspace allocation might be delayed */
		return H_TOO_HARD;

	pua = (void *) vmalloc_to_phys(pua);
	if (WARN_ON_ONCE_RM(!pua))
		return H_HARDWARE;

	mem = mm_iommu_lookup_rm(kvm->mm, *pua, pgsize);
	if (!mem)
		return H_TOO_HARD;

	mm_iommu_mapped_dec(mem);

	*pua = 0;

	return H_SUCCESS;
}

static long kvmppc_rm_tce_iommu_unmap(struct kvm *kvm,
		struct iommu_table *tbl, unsigned long entry)
{
	enum dma_data_direction dir = DMA_NONE;
	unsigned long hpa = 0;
	long ret;

	if (iommu_tce_xchg_rm(tbl, entry, &hpa, &dir))
		/*
		 * real mode xchg can fail if struct page crosses
		 * a page boundary
		 */
		return H_TOO_HARD;

	if (dir == DMA_NONE)
		return H_SUCCESS;

	ret = kvmppc_rm_tce_iommu_mapped_dec(kvm, tbl, entry);
	if (ret)
		iommu_tce_xchg_rm(tbl, entry, &hpa, &dir);

	return ret;
}

static long kvmppc_rm_tce_iommu_map(struct kvm *kvm, struct iommu_table *tbl,
		unsigned long entry, unsigned long ua,
		enum dma_data_direction dir)
{
	long ret;
	unsigned long hpa = 0;
	unsigned long *pua = IOMMU_TABLE_USERSPACE_ENTRY(tbl, entry);
	struct mm_iommu_table_group_mem_t *mem;

	if (!pua)
		/* it_userspace allocation might be delayed */
		return H_TOO_HARD;

	mem = mm_iommu_lookup_rm(kvm->mm, ua, 1ULL << tbl->it_page_shift);
	if (!mem)
		return H_TOO_HARD;

	if (WARN_ON_ONCE_RM(mm_iommu_ua_to_hpa_rm(mem, ua, &hpa)))
		return H_HARDWARE;

	pua = (void *) vmalloc_to_phys(pua);
	if (WARN_ON_ONCE_RM(!pua))
		return H_HARDWARE;

	if (WARN_ON_ONCE_RM(mm_iommu_mapped_inc(mem)))
		return H_CLOSED;

	ret = iommu_tce_xchg_rm(tbl, entry, &hpa, &dir);
	if (ret) {
		mm_iommu_mapped_dec(mem);
		/*
		 * real mode xchg can fail if struct page crosses
		 * a page boundary
		 */
		return H_TOO_HARD;
	}

	if (dir != DMA_NONE)
		kvmppc_rm_tce_iommu_mapped_dec(kvm, tbl, entry);

	*pua = ua;

	return 0;
}

long kvmppc_rm_h_put_tce(struct kvm_vcpu *vcpu, unsigned long liobn,
		unsigned long ioba, unsigned long tce)
{
	struct kvmppc_spapr_tce_table *stt;
	long ret;
	struct kvmppc_spapr_tce_iommu_table *stit;
	unsigned long entry, ua = 0;
	enum dma_data_direction dir;

	/* udbg_printf("H_PUT_TCE(): liobn=0x%lx ioba=0x%lx, tce=0x%lx\n", */
	/* 	    liobn, ioba, tce); */

	/* For radix, we might be in virtual mode, so punt */
	if (kvm_is_radix(vcpu->kvm))
		return H_TOO_HARD;

	stt = kvmppc_find_table(vcpu->kvm, liobn);
	if (!stt)
		return H_TOO_HARD;

	ret = kvmppc_ioba_validate(stt, ioba, 1);
	if (ret != H_SUCCESS)
		return ret;

	ret = kvmppc_tce_validate(stt, tce);
	if (ret != H_SUCCESS)
		return ret;

	dir = iommu_tce_direction(tce);
	if ((dir != DMA_NONE) && kvmppc_gpa_to_ua(vcpu->kvm,
			tce & ~(TCE_PCI_READ | TCE_PCI_WRITE), &ua, NULL))
		return H_PARAMETER;

	entry = ioba >> stt->page_shift;

	list_for_each_entry_lockless(stit, &stt->iommu_tables, next) {
		if (dir == DMA_NONE)
			ret = kvmppc_rm_tce_iommu_unmap(vcpu->kvm,
					stit->tbl, entry);
		else
			ret = kvmppc_rm_tce_iommu_map(vcpu->kvm,
					stit->tbl, entry, ua, dir);

		if (ret == H_SUCCESS)
			continue;

		if (ret == H_TOO_HARD)
			return ret;

		WARN_ON_ONCE_RM(1);
		kvmppc_rm_clear_tce(stit->tbl, entry);
	}

	kvmppc_tce_put(stt, entry, tce);

	return H_SUCCESS;
}

static long kvmppc_rm_ua_to_hpa(struct kvm_vcpu *vcpu,
		unsigned long ua, unsigned long *phpa)
{
	pte_t *ptep, pte;
	unsigned shift = 0;

	ptep = __find_linux_pte_or_hugepte(vcpu->arch.pgdir, ua, NULL, &shift);
	if (!ptep || !pte_present(*ptep))
		return -ENXIO;
	pte = *ptep;

	if (!shift)
		shift = PAGE_SHIFT;

	/* Avoid handling anything potentially complicated in realmode */
	if (shift > PAGE_SHIFT)
		return -EAGAIN;

	if (!pte_young(pte))
		return -EAGAIN;

	*phpa = (pte_pfn(pte) << PAGE_SHIFT) | (ua & ((1ULL << shift) - 1)) |
			(ua & ~PAGE_MASK);

	return 0;
}

long kvmppc_rm_h_put_tce_indirect(struct kvm_vcpu *vcpu,
		unsigned long liobn, unsigned long ioba,
		unsigned long tce_list,	unsigned long npages)
{
	struct kvmppc_spapr_tce_table *stt;
	long i, ret = H_SUCCESS;
	unsigned long tces, entry, ua = 0;
	unsigned long *rmap = NULL;
	bool prereg = false;
	struct kvmppc_spapr_tce_iommu_table *stit;

	/* For radix, we might be in virtual mode, so punt */
	if (kvm_is_radix(vcpu->kvm))
		return H_TOO_HARD;

	stt = kvmppc_find_table(vcpu->kvm, liobn);
	if (!stt)
		return H_TOO_HARD;

	entry = ioba >> stt->page_shift;
	/*
	 * The spec says that the maximum size of the list is 512 TCEs
	 * so the whole table addressed resides in 4K page
	 */
	if (npages > 512)
		return H_PARAMETER;

	if (tce_list & (SZ_4K - 1))
		return H_PARAMETER;

	ret = kvmppc_ioba_validate(stt, ioba, npages);
	if (ret != H_SUCCESS)
		return ret;

	if (mm_iommu_preregistered(vcpu->kvm->mm)) {
		/*
		 * We get here if guest memory was pre-registered which
		 * is normally VFIO case and gpa->hpa translation does not
		 * depend on hpt.
		 */
		struct mm_iommu_table_group_mem_t *mem;

		if (kvmppc_gpa_to_ua(vcpu->kvm, tce_list, &ua, NULL))
			return H_TOO_HARD;

		mem = mm_iommu_lookup_rm(vcpu->kvm->mm, ua, IOMMU_PAGE_SIZE_4K);
		if (mem)
			prereg = mm_iommu_ua_to_hpa_rm(mem, ua, &tces) == 0;
	}

	if (!prereg) {
		/*
		 * This is usually a case of a guest with emulated devices only
		 * when TCE list is not in preregistered memory.
		 * We do not require memory to be preregistered in this case
		 * so lock rmap and do __find_linux_pte_or_hugepte().
		 */
		if (kvmppc_gpa_to_ua(vcpu->kvm, tce_list, &ua, &rmap))
			return H_TOO_HARD;

		rmap = (void *) vmalloc_to_phys(rmap);
		if (WARN_ON_ONCE_RM(!rmap))
			return H_HARDWARE;

		/*
		 * Synchronize with the MMU notifier callbacks in
		 * book3s_64_mmu_hv.c (kvm_unmap_hva_hv etc.).
		 * While we have the rmap lock, code running on other CPUs
		 * cannot finish unmapping the host real page that backs
		 * this guest real page, so we are OK to access the host
		 * real page.
		 */
		lock_rmap(rmap);
		if (kvmppc_rm_ua_to_hpa(vcpu, ua, &tces)) {
			ret = H_TOO_HARD;
			goto unlock_exit;
		}
	}

	for (i = 0; i < npages; ++i) {
		unsigned long tce = be64_to_cpu(((u64 *)tces)[i]);

		ret = kvmppc_tce_validate(stt, tce);
		if (ret != H_SUCCESS)
			goto unlock_exit;

		ua = 0;
		if (kvmppc_gpa_to_ua(vcpu->kvm,
				tce & ~(TCE_PCI_READ | TCE_PCI_WRITE),
				&ua, NULL))
			return H_PARAMETER;

		list_for_each_entry_lockless(stit, &stt->iommu_tables, next) {
			ret = kvmppc_rm_tce_iommu_map(vcpu->kvm,
					stit->tbl, entry + i, ua,
					iommu_tce_direction(tce));

			if (ret == H_SUCCESS)
				continue;

			if (ret == H_TOO_HARD)
				goto unlock_exit;

			WARN_ON_ONCE_RM(1);
			kvmppc_rm_clear_tce(stit->tbl, entry);
		}

		kvmppc_tce_put(stt, entry + i, tce);
	}

unlock_exit:
	if (rmap)
		unlock_rmap(rmap);

	return ret;
}

long kvmppc_rm_h_stuff_tce(struct kvm_vcpu *vcpu,
		unsigned long liobn, unsigned long ioba,
		unsigned long tce_value, unsigned long npages)
{
	struct kvmppc_spapr_tce_table *stt;
	long i, ret;
	struct kvmppc_spapr_tce_iommu_table *stit;

	/* For radix, we might be in virtual mode, so punt */
	if (kvm_is_radix(vcpu->kvm))
		return H_TOO_HARD;

	stt = kvmppc_find_table(vcpu->kvm, liobn);
	if (!stt)
		return H_TOO_HARD;

	ret = kvmppc_ioba_validate(stt, ioba, npages);
	if (ret != H_SUCCESS)
		return ret;

	/* Check permission bits only to allow userspace poison TCE for debug */
	if (tce_value & (TCE_PCI_WRITE | TCE_PCI_READ))
		return H_PARAMETER;

	list_for_each_entry_lockless(stit, &stt->iommu_tables, next) {
		unsigned long entry = ioba >> stit->tbl->it_page_shift;

		for (i = 0; i < npages; ++i) {
			ret = kvmppc_rm_tce_iommu_unmap(vcpu->kvm,
					stit->tbl, entry + i);

			if (ret == H_SUCCESS)
				continue;

			if (ret == H_TOO_HARD)
				return ret;

			WARN_ON_ONCE_RM(1);
			kvmppc_rm_clear_tce(stit->tbl, entry);
		}
	}

	for (i = 0; i < npages; ++i, ioba += (1ULL << stt->page_shift))
		kvmppc_tce_put(stt, ioba >> stt->page_shift, tce_value);

	return H_SUCCESS;
}

/* This can be called in either virtual mode or real mode */
long kvmppc_h_get_tce(struct kvm_vcpu *vcpu, unsigned long liobn,
		      unsigned long ioba)
{
	struct kvmppc_spapr_tce_table *stt;
	long ret;
	unsigned long idx;
	struct page *page;
	u64 *tbl;

	stt = kvmppc_find_table(vcpu->kvm, liobn);
	if (!stt)
		return H_TOO_HARD;

	ret = kvmppc_ioba_validate(stt, ioba, 1);
	if (ret != H_SUCCESS)
		return ret;

	idx = (ioba >> stt->page_shift) - stt->offset;
	page = stt->pages[idx / TCES_PER_PAGE];
	tbl = (u64 *)page_address(page);

	vcpu->arch.gpr[4] = tbl[idx % TCES_PER_PAGE];

	return H_SUCCESS;
}
EXPORT_SYMBOL_GPL(kvmppc_h_get_tce);

#endif /* KVM_BOOK3S_HV_POSSIBLE */
Commit	Line	Data
54738c09 DG	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	* This program is distributed in the hope that it will be useful,
	7	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	8	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	9	* GNU General Public License for more details.
	10	*
	11	* You should have received a copy of the GNU General Public License
	12	* along with this program; if not, write to the Free Software
	13	* Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
	14	*
	15	* Copyright 2010 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com>
	16	* Copyright 2011 David Gibson, IBM Corporation <dwg@au1.ibm.com>
d3695aa4	17	* Copyright 2016 Alexey Kardashevskiy, IBM Corporation <aik@au1.ibm.com>
54738c09 DG	18	*/
	19
	20	#include <linux/types.h>
	21	#include <linux/string.h>
	22	#include <linux/kvm.h>
	23	#include <linux/kvm_host.h>
	24	#include <linux/highmem.h>
	25	#include <linux/gfp.h>
	26	#include <linux/slab.h>
	27	#include <linux/hugetlb.h>
	28	#include <linux/list.h>
	29
	30	#include <asm/tlbflush.h>
	31	#include <asm/kvm_ppc.h>
	32	#include <asm/kvm_book3s.h>
f64e8084	33	#include <asm/book3s/64/mmu-hash.h>
d3695aa4	34	#include <asm/mmu_context.h>
54738c09 DG	35	#include <asm/hvcall.h>
	36	#include <asm/synch.h>
	37	#include <asm/ppc-opcode.h>
	38	#include <asm/kvm_host.h>
	39	#include <asm/udbg.h>
fcbb2ce6	40	#include <asm/iommu.h>
5ee7af18	41	#include <asm/tce.h>
54738c09	42
20464b9b AK	43	#ifdef CONFIG_BUG
	44
	45	#define WARN_ON_ONCE_RM(condition) ({ \
	46	static bool __section(.data.unlikely) __warned; \
	47	int __ret_warn_once = !!(condition); \
	48	\
	49	if (unlikely(__ret_warn_once && !__warned)) { \
	50	__warned = true; \
	51	pr_err("WARN_ON_ONCE_RM: (%s) at %s:%u\n", \
	52	__stringify(condition), \
	53	__func__, __LINE__); \
	54	dump_stack(); \
	55	} \
	56	unlikely(__ret_warn_once); \
	57	})
	58
	59	#else
	60
	61	#define WARN_ON_ONCE_RM(condition) ({ \
	62	int __ret_warn_on = !!(condition); \
	63	unlikely(__ret_warn_on); \
	64	})
	65
	66	#endif
	67
54738c09 DG	68	#define TCES_PER_PAGE (PAGE_SIZE / sizeof(u64))
54738c09 DG	69
fcbb2ce6 AK	70	/*
	71	* Finds a TCE table descriptor by LIOBN.
	72	*
	73	* WARNING: This will be called in real or virtual mode on HV KVM and virtual
	74	* mode on PR KVM
	75	*/
69e0373c	76	struct kvmppc_spapr_tce_table kvmppc_find_table(struct kvm kvm,
fcbb2ce6 AK	77	unsigned long liobn)
fcbb2ce6 AK	78	{
fcbb2ce6 AK	79	struct kvmppc_spapr_tce_table *stt;
fcbb2ce6 AK	80
366baf28	81	list_for_each_entry_lockless(stt, &kvm->arch.spapr_tce_tables, list)
fcbb2ce6 AK	82	if (stt->liobn == liobn)
	83	return stt;
	84
	85	return NULL;
	86	}
d3695aa4	87	EXPORT_SYMBOL_GPL(kvmppc_find_table);
fcbb2ce6 AK	88
	89	/*
	90	* Validates IO address.
	91	*
	92	* WARNING: This will be called in real-mode on HV KVM and virtual
	93	* mode on PR KVM
	94	*/
5ee7af18	95	long kvmppc_ioba_validate(struct kvmppc_spapr_tce_table *stt,
fcbb2ce6 AK	96	unsigned long ioba, unsigned long npages)
fcbb2ce6 AK	97	{
fe26e527 AK	98	unsigned long mask = (1ULL << stt->page_shift) - 1;
fe26e527 AK	99	unsigned long idx = ioba >> stt->page_shift;
fcbb2ce6	100
14f853f1 AK	101	if ((ioba & mask) \|\| (idx < stt->offset) \|\|
	102	(idx - stt->offset + npages > stt->size) \|\|
	103	(idx + npages < idx))
fcbb2ce6 AK	104	return H_PARAMETER;
	105
	106	return H_SUCCESS;
	107	}
5ee7af18 AK	108	EXPORT_SYMBOL_GPL(kvmppc_ioba_validate);
	109
	110	/*
	111	* Validates TCE address.
	112	* At the moment flags and page mask are validated.
	113	* As the host kernel does not access those addresses (just puts them
	114	* to the table and user space is supposed to process them), we can skip
	115	* checking other things (such as TCE is a guest RAM address or the page
	116	* was actually allocated).
	117	*
	118	* WARNING: This will be called in real-mode on HV KVM and virtual
	119	* mode on PR KVM
	120	*/
	121	long kvmppc_tce_validate(struct kvmppc_spapr_tce_table *stt, unsigned long tce)
	122	{
fe26e527 AK	123	unsigned long page_mask = ~((1ULL << stt->page_shift) - 1);
fe26e527 AK	124	unsigned long mask = ~(page_mask \| TCE_PCI_WRITE \| TCE_PCI_READ);
5ee7af18 AK	125
	126	if (tce & mask)
	127	return H_PARAMETER;
	128
	129	return H_SUCCESS;
	130	}
	131	EXPORT_SYMBOL_GPL(kvmppc_tce_validate);
	132
	133	/* Note on the use of page_address() in real mode,
	134	*
	135	* It is safe to use page_address() in real mode on ppc64 because
	136	* page_address() is always defined as lowmem_page_address()
	137	* which returns __va(PFN_PHYS(page_to_pfn(page))) which is arithmetic
	138	* operation and does not access page struct.
	139	*
	140	* Theoretically page_address() could be defined different
	141	* but either WANT_PAGE_VIRTUAL or HASHED_PAGE_VIRTUAL
	142	* would have to be enabled.
	143	* WANT_PAGE_VIRTUAL is never enabled on ppc32/ppc64,
	144	* HASHED_PAGE_VIRTUAL could be enabled for ppc32 only and only
	145	* if CONFIG_HIGHMEM is defined. As CONFIG_SPARSEMEM_VMEMMAP
	146	* is not expected to be enabled on ppc32, page_address()
	147	* is safe for ppc32 as well.
	148	*
	149	* WARNING: This will be called in real-mode on HV KVM and virtual
	150	* mode on PR KVM
	151	*/
	152	static u64 kvmppc_page_address(struct page page)
	153	{
	154	#if defined(HASHED_PAGE_VIRTUAL) \|\| defined(WANT_PAGE_VIRTUAL)
	155	#error TODO: fix to avoid page_address() here
	156	#endif
	157	return (u64 *) page_address(page);
	158	}
	159
	160	/*
	161	* Handles TCE requests for emulated devices.
	162	* Puts guest TCE values to the table and expects user space to convert them.
	163	* Called in both real and virtual modes.
	164	* Cannot fail so kvmppc_tce_validate must be called before it.
	165	*
	166	* WARNING: This will be called in real-mode on HV KVM and virtual
	167	* mode on PR KVM
	168	*/
	169	void kvmppc_tce_put(struct kvmppc_spapr_tce_table *stt,
	170	unsigned long idx, unsigned long tce)
	171	{
	172	struct page *page;
	173	u64 *tbl;
	174
14f853f1	175	idx -= stt->offset;
5ee7af18 AK	176	page = stt->pages[idx / TCES_PER_PAGE];
	177	tbl = kvmppc_page_address(page);
	178
	179	tbl[idx % TCES_PER_PAGE] = tce;
	180	}
	181	EXPORT_SYMBOL_GPL(kvmppc_tce_put);
fcbb2ce6	182
d3695aa4 AK	183	long kvmppc_gpa_to_ua(struct kvm *kvm, unsigned long gpa,
	184	unsigned long ua, unsigned long *prmap)
	185	{
	186	unsigned long gfn = gpa >> PAGE_SHIFT;
	187	struct kvm_memory_slot *memslot;
	188
	189	memslot = search_memslots(kvm_memslots(kvm), gfn);
	190	if (!memslot)
	191	return -EINVAL;
	192
	193	*ua = __gfn_to_hva_memslot(memslot, gfn) \|
	194	(gpa & ~(PAGE_MASK \| TCE_PCI_READ \| TCE_PCI_WRITE));
	195
	196	#ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
	197	if (prmap)
	198	*prmap = &memslot->arch.rmap[gfn - memslot->base_gfn];
	199	#endif
	200
	201	return 0;
	202	}
	203	EXPORT_SYMBOL_GPL(kvmppc_gpa_to_ua);
	204
	205	#ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
20464b9b AK	206	static void kvmppc_rm_clear_tce(struct iommu_table *tbl, unsigned long entry)
	207	{
	208	unsigned long hpa = 0;
	209	enum dma_data_direction dir = DMA_NONE;
	210
	211	iommu_tce_xchg_rm(tbl, entry, &hpa, &dir);
	212	}
	213
	214	static long kvmppc_rm_tce_iommu_mapped_dec(struct kvm *kvm,
	215	struct iommu_table *tbl, unsigned long entry)
	216	{
	217	struct mm_iommu_table_group_mem_t *mem = NULL;
	218	const unsigned long pgsize = 1ULL << tbl->it_page_shift;
	219	unsigned long *pua = IOMMU_TABLE_USERSPACE_ENTRY(tbl, entry);
	220
	221	if (!pua)
	222	/* it_userspace allocation might be delayed */
	223	return H_TOO_HARD;
	224
	225	pua = (void *) vmalloc_to_phys(pua);
	226	if (WARN_ON_ONCE_RM(!pua))
	227	return H_HARDWARE;
	228
	229	mem = mm_iommu_lookup_rm(kvm->mm, *pua, pgsize);
	230	if (!mem)
	231	return H_TOO_HARD;
	232
	233	mm_iommu_mapped_dec(mem);
	234
	235	*pua = 0;
	236
	237	return H_SUCCESS;
	238	}
	239
	240	static long kvmppc_rm_tce_iommu_unmap(struct kvm *kvm,
	241	struct iommu_table *tbl, unsigned long entry)
	242	{
	243	enum dma_data_direction dir = DMA_NONE;
	244	unsigned long hpa = 0;
	245	long ret;
	246
	247	if (iommu_tce_xchg_rm(tbl, entry, &hpa, &dir))
	248	/*
	249	* real mode xchg can fail if struct page crosses
	250	* a page boundary
	251	*/
	252	return H_TOO_HARD;
	253
	254	if (dir == DMA_NONE)
	255	return H_SUCCESS;
	256
	257	ret = kvmppc_rm_tce_iommu_mapped_dec(kvm, tbl, entry);
	258	if (ret)
	259	iommu_tce_xchg_rm(tbl, entry, &hpa, &dir);
	260
	261	return ret;
	262	}
	263
	264	static long kvmppc_rm_tce_iommu_map(struct kvm kvm, struct iommu_table tbl,
	265	unsigned long entry, unsigned long ua,
	266	enum dma_data_direction dir)
	267	{
	268	long ret;
	269	unsigned long hpa = 0;
270	unsigned long *pua = IOMMU_TABLE_USERSPACE_ENTRY(tbl, entry);
271	struct mm_iommu_table_group_mem_t *mem;
272
273	if (!pua)
274	/* it_userspace allocation might be delayed */
275	return H_TOO_HARD;
276
277	mem = mm_iommu_lookup_rm(kvm->mm, ua, 1ULL << tbl->it_page_shift);
278	if (!mem)
279	return H_TOO_HARD;
280
281	if (WARN_ON_ONCE_RM(mm_iommu_ua_to_hpa_rm(mem, ua, &hpa)))
282	return H_HARDWARE;
283
284	pua = (void *) vmalloc_to_phys(pua);
285	if (WARN_ON_ONCE_RM(!pua))
286	return H_HARDWARE;
287
288	if (WARN_ON_ONCE_RM(mm_iommu_mapped_inc(mem)))
289	return H_CLOSED;
290
291	ret = iommu_tce_xchg_rm(tbl, entry, &hpa, &dir);
292	if (ret) {
293	mm_iommu_mapped_dec(mem);
294	/*
295	* real mode xchg can fail if struct page crosses
296	* a page boundary
297	*/
298	return H_TOO_HARD;
299	}
300
301	if (dir != DMA_NONE)
302	kvmppc_rm_tce_iommu_mapped_dec(kvm, tbl, entry);
303
304	*pua = ua;
305
306	return 0;
307	}
308
31217db7 AK	309	long kvmppc_rm_h_put_tce(struct kvm_vcpu *vcpu, unsigned long liobn,
31217db7 AK	310	unsigned long ioba, unsigned long tce)
54738c09	311	{
69e0373c	312	struct kvmppc_spapr_tce_table *stt;
fcbb2ce6	313	long ret;
20464b9b AK	314	struct kvmppc_spapr_tce_iommu_table *stit;
	315	unsigned long entry, ua = 0;
	316	enum dma_data_direction dir;
54738c09 DG	317
	318	/* udbg_printf("H_PUT_TCE(): liobn=0x%lx ioba=0x%lx, tce=0x%lx\n", */
	319	/* liobn, ioba, tce); */
	320
791d5db2 PM	321	/* For radix, we might be in virtual mode, so punt */
	322	if (kvm_is_radix(vcpu->kvm))
	323	return H_TOO_HARD;
	324
69e0373c	325	stt = kvmppc_find_table(vcpu->kvm, liobn);
fcbb2ce6 AK	326	if (!stt)
	327	return H_TOO_HARD;
	328
	329	ret = kvmppc_ioba_validate(stt, ioba, 1);
	330	if (ret != H_SUCCESS)
	331	return ret;
	332
5ee7af18 AK	333	ret = kvmppc_tce_validate(stt, tce);
	334	if (ret != H_SUCCESS)
	335	return ret;
fcbb2ce6	336
20464b9b AK	337	dir = iommu_tce_direction(tce);
	338	if ((dir != DMA_NONE) && kvmppc_gpa_to_ua(vcpu->kvm,
	339	tce & ~(TCE_PCI_READ \| TCE_PCI_WRITE), &ua, NULL))
	340	return H_PARAMETER;
	341
	342	entry = ioba >> stt->page_shift;
	343
	344	list_for_each_entry_lockless(stit, &stt->iommu_tables, next) {
	345	if (dir == DMA_NONE)
	346	ret = kvmppc_rm_tce_iommu_unmap(vcpu->kvm,
	347	stit->tbl, entry);
	348	else
	349	ret = kvmppc_rm_tce_iommu_map(vcpu->kvm,
	350	stit->tbl, entry, ua, dir);
	351
	352	if (ret == H_SUCCESS)
	353	continue;
	354
	355	if (ret == H_TOO_HARD)
	356	return ret;
	357
	358	WARN_ON_ONCE_RM(1);
	359	kvmppc_rm_clear_tce(stit->tbl, entry);
	360	}
	361
	362	kvmppc_tce_put(stt, entry, tce);
fcbb2ce6 AK	363
fcbb2ce6 AK	364	return H_SUCCESS;
54738c09	365	}
69e9fbb2	366
d3695aa4 AK	367	static long kvmppc_rm_ua_to_hpa(struct kvm_vcpu *vcpu,
	368	unsigned long ua, unsigned long *phpa)
	369	{
	370	pte_t *ptep, pte;
	371	unsigned shift = 0;
	372
	373	ptep = __find_linux_pte_or_hugepte(vcpu->arch.pgdir, ua, NULL, &shift);
	374	if (!ptep \|\| !pte_present(*ptep))
	375	return -ENXIO;
	376	pte = *ptep;
	377
	378	if (!shift)
	379	shift = PAGE_SHIFT;
	380
	381	/* Avoid handling anything potentially complicated in realmode */
	382	if (shift > PAGE_SHIFT)
	383	return -EAGAIN;
	384
	385	if (!pte_young(pte))
	386	return -EAGAIN;
	387
	388	*phpa = (pte_pfn(pte) << PAGE_SHIFT) \| (ua & ((1ULL << shift) - 1)) \|
	389	(ua & ~PAGE_MASK);
	390
	391	return 0;
	392	}
	393
	394	long kvmppc_rm_h_put_tce_indirect(struct kvm_vcpu *vcpu,
	395	unsigned long liobn, unsigned long ioba,
	396	unsigned long tce_list, unsigned long npages)
	397	{
	398	struct kvmppc_spapr_tce_table *stt;
	399	long i, ret = H_SUCCESS;
	400	unsigned long tces, entry, ua = 0;
	401	unsigned long *rmap = NULL;
dde1b0df	402	bool prereg = false;
20464b9b	403	struct kvmppc_spapr_tce_iommu_table *stit;
d3695aa4	404
791d5db2 PM	405	/* For radix, we might be in virtual mode, so punt */
	406	if (kvm_is_radix(vcpu->kvm))
	407	return H_TOO_HARD;
	408
69e0373c	409	stt = kvmppc_find_table(vcpu->kvm, liobn);
d3695aa4 AK	410	if (!stt)
	411	return H_TOO_HARD;
	412
fe26e527	413	entry = ioba >> stt->page_shift;
d3695aa4 AK	414	/*
	415	* The spec says that the maximum size of the list is 512 TCEs
	416	* so the whole table addressed resides in 4K page
	417	*/
	418	if (npages > 512)
	419	return H_PARAMETER;
	420
	421	if (tce_list & (SZ_4K - 1))
	422	return H_PARAMETER;
	423
	424	ret = kvmppc_ioba_validate(stt, ioba, npages);
	425	if (ret != H_SUCCESS)
	426	return ret;
	427
dde1b0df AK	428	if (mm_iommu_preregistered(vcpu->kvm->mm)) {
	429	/*
	430	* We get here if guest memory was pre-registered which
	431	* is normally VFIO case and gpa->hpa translation does not
	432	* depend on hpt.
	433	*/
	434	struct mm_iommu_table_group_mem_t *mem;
d3695aa4	435
dde1b0df AK	436	if (kvmppc_gpa_to_ua(vcpu->kvm, tce_list, &ua, NULL))
dde1b0df AK	437	return H_TOO_HARD;
d3695aa4	438
dde1b0df AK	439	mem = mm_iommu_lookup_rm(vcpu->kvm->mm, ua, IOMMU_PAGE_SIZE_4K);
	440	if (mem)
	441	prereg = mm_iommu_ua_to_hpa_rm(mem, ua, &tces) == 0;
	442	}
	443
	444	if (!prereg) {
	445	/*
	446	* This is usually a case of a guest with emulated devices only
	447	* when TCE list is not in preregistered memory.
	448	* We do not require memory to be preregistered in this case
	449	* so lock rmap and do __find_linux_pte_or_hugepte().
	450	*/
	451	if (kvmppc_gpa_to_ua(vcpu->kvm, tce_list, &ua, &rmap))
	452	return H_TOO_HARD;
	453
	454	rmap = (void *) vmalloc_to_phys(rmap);
20464b9b AK	455	if (WARN_ON_ONCE_RM(!rmap))
20464b9b AK	456	return H_HARDWARE;
dde1b0df AK	457
	458	/*
	459	* Synchronize with the MMU notifier callbacks in
	460	* book3s_64_mmu_hv.c (kvm_unmap_hva_hv etc.).
	461	* While we have the rmap lock, code running on other CPUs
	462	* cannot finish unmapping the host real page that backs
	463	* this guest real page, so we are OK to access the host
	464	* real page.
	465	*/
	466	lock_rmap(rmap);
	467	if (kvmppc_rm_ua_to_hpa(vcpu, ua, &tces)) {
	468	ret = H_TOO_HARD;
	469	goto unlock_exit;
	470	}
d3695aa4 AK	471	}
	472
	473	for (i = 0; i < npages; ++i) {
	474	unsigned long tce = be64_to_cpu(((u64 *)tces)[i]);
	475
	476	ret = kvmppc_tce_validate(stt, tce);
	477	if (ret != H_SUCCESS)
	478	goto unlock_exit;
	479
20464b9b AK	480	ua = 0;
	481	if (kvmppc_gpa_to_ua(vcpu->kvm,
	482	tce & ~(TCE_PCI_READ \| TCE_PCI_WRITE),
	483	&ua, NULL))
	484	return H_PARAMETER;
	485
	486	list_for_each_entry_lockless(stit, &stt->iommu_tables, next) {
	487	ret = kvmppc_rm_tce_iommu_map(vcpu->kvm,
	488	stit->tbl, entry + i, ua,
	489	iommu_tce_direction(tce));
	490
	491	if (ret == H_SUCCESS)
	492	continue;
	493
	494	if (ret == H_TOO_HARD)
	495	goto unlock_exit;
	496
	497	WARN_ON_ONCE_RM(1);
	498	kvmppc_rm_clear_tce(stit->tbl, entry);
	499	}
	500
d3695aa4 AK	501	kvmppc_tce_put(stt, entry + i, tce);
	502	}
	503
	504	unlock_exit:
dde1b0df AK	505	if (rmap)
dde1b0df AK	506	unlock_rmap(rmap);
d3695aa4 AK	507
	508	return ret;
	509	}
	510
31217db7	511	long kvmppc_rm_h_stuff_tce(struct kvm_vcpu *vcpu,
d3695aa4 AK	512	unsigned long liobn, unsigned long ioba,
	513	unsigned long tce_value, unsigned long npages)
	514	{
	515	struct kvmppc_spapr_tce_table *stt;
	516	long i, ret;
20464b9b	517	struct kvmppc_spapr_tce_iommu_table *stit;
d3695aa4	518
791d5db2 PM	519	/* For radix, we might be in virtual mode, so punt */
	520	if (kvm_is_radix(vcpu->kvm))
	521	return H_TOO_HARD;
	522
69e0373c	523	stt = kvmppc_find_table(vcpu->kvm, liobn);
d3695aa4 AK	524	if (!stt)
	525	return H_TOO_HARD;
	526
	527	ret = kvmppc_ioba_validate(stt, ioba, npages);
	528	if (ret != H_SUCCESS)
	529	return ret;
	530
	531	/* Check permission bits only to allow userspace poison TCE for debug */
	532	if (tce_value & (TCE_PCI_WRITE \| TCE_PCI_READ))
	533	return H_PARAMETER;
	534
20464b9b AK	535	list_for_each_entry_lockless(stit, &stt->iommu_tables, next) {
	536	unsigned long entry = ioba >> stit->tbl->it_page_shift;
	537
	538	for (i = 0; i < npages; ++i) {
	539	ret = kvmppc_rm_tce_iommu_unmap(vcpu->kvm,
	540	stit->tbl, entry + i);
	541
	542	if (ret == H_SUCCESS)
	543	continue;
	544
	545	if (ret == H_TOO_HARD)
	546	return ret;
	547
	548	WARN_ON_ONCE_RM(1);
	549	kvmppc_rm_clear_tce(stit->tbl, entry);
	550	}
	551	}
	552
fe26e527 AK	553	for (i = 0; i < npages; ++i, ioba += (1ULL << stt->page_shift))
fe26e527 AK	554	kvmppc_tce_put(stt, ioba >> stt->page_shift, tce_value);
d3695aa4 AK	555
	556	return H_SUCCESS;
	557	}
d3695aa4	558
791d5db2	559	/* This can be called in either virtual mode or real mode */
69e9fbb2 LD	560	long kvmppc_h_get_tce(struct kvm_vcpu *vcpu, unsigned long liobn,
	561	unsigned long ioba)
	562	{
69e0373c	563	struct kvmppc_spapr_tce_table *stt;
fcbb2ce6 AK	564	long ret;
	565	unsigned long idx;
	566	struct page *page;
	567	u64 *tbl;
69e9fbb2	568
69e0373c	569	stt = kvmppc_find_table(vcpu->kvm, liobn);
fcbb2ce6 AK	570	if (!stt)
fcbb2ce6 AK	571	return H_TOO_HARD;
69e9fbb2	572
fcbb2ce6 AK	573	ret = kvmppc_ioba_validate(stt, ioba, 1);
	574	if (ret != H_SUCCESS)
	575	return ret;
69e9fbb2	576
14f853f1	577	idx = (ioba >> stt->page_shift) - stt->offset;
fcbb2ce6 AK	578	page = stt->pages[idx / TCES_PER_PAGE];
fcbb2ce6 AK	579	tbl = (u64 *)page_address(page);
69e9fbb2	580
fcbb2ce6	581	vcpu->arch.gpr[4] = tbl[idx % TCES_PER_PAGE];
69e9fbb2	582
fcbb2ce6	583	return H_SUCCESS;
69e9fbb2 LD	584	}
69e9fbb2 LD	585	EXPORT_SYMBOL_GPL(kvmppc_h_get_tce);
d3695aa4 AK	586
d3695aa4 AK	587	#endif /* KVM_BOOK3S_HV_POSSIBLE */