[linux-2.6-block.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>
#include <asm/pte-walk.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 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 gpa = tce & ~(TCE_PCI_READ | TCE_PCI_WRITE);
	enum dma_data_direction dir = iommu_tce_direction(tce);

	/* Allow userspace to poison TCE table */
	if (dir == DMA_NONE)
		return H_SUCCESS;

	if (iommu_tce_check_gpa(stt->page_shift, gpa))
		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;

	/*
	 * Called in real mode with MSR_EE = 0. We are safe here.
	 * It is ok to do the lookup with arch.pgdir here, because
	 * we are doing this on secondary cpus and current task there
	 * is not the hypervisor. Also this is safe against THP in the
	 * host, because an IPI to primary thread will wait for the secondary
	 * to exit which will agains result in the below page table walk
	 * to finish.
	 */
	ptep = __find_linux_pte(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_range_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>
94171b19	42	#include <asm/pte-walk.h>
54738c09	43
121f80ba AK	44	#ifdef CONFIG_BUG
	45
	46	#define WARN_ON_ONCE_RM(condition) ({ \
	47	static bool __section(.data.unlikely) __warned; \
	48	int __ret_warn_once = !!(condition); \
	49	\
	50	if (unlikely(__ret_warn_once && !__warned)) { \
	51	__warned = true; \
	52	pr_err("WARN_ON_ONCE_RM: (%s) at %s:%u\n", \
	53	__stringify(condition), \
	54	__func__, __LINE__); \
	55	dump_stack(); \
	56	} \
	57	unlikely(__ret_warn_once); \
	58	})
	59
	60	#else
	61
	62	#define WARN_ON_ONCE_RM(condition) ({ \
	63	int __ret_warn_on = !!(condition); \
	64	unlikely(__ret_warn_on); \
	65	})
	66
	67	#endif
	68
54738c09 DG	69	#define TCES_PER_PAGE (PAGE_SIZE / sizeof(u64))
54738c09 DG	70
fcbb2ce6 AK	71	/*
	72	* Finds a TCE table descriptor by LIOBN.
	73	*
	74	* WARNING: This will be called in real or virtual mode on HV KVM and virtual
	75	* mode on PR KVM
	76	*/
503bfcbe	77	struct kvmppc_spapr_tce_table kvmppc_find_table(struct kvm kvm,
fcbb2ce6 AK	78	unsigned long liobn)
fcbb2ce6 AK	79	{
fcbb2ce6 AK	80	struct kvmppc_spapr_tce_table *stt;
fcbb2ce6 AK	81
366baf28	82	list_for_each_entry_lockless(stt, &kvm->arch.spapr_tce_tables, list)
fcbb2ce6 AK	83	if (stt->liobn == liobn)
	84	return stt;
	85
	86	return NULL;
	87	}
d3695aa4	88	EXPORT_SYMBOL_GPL(kvmppc_find_table);
fcbb2ce6	89
5ee7af18 AK	90	/*
	91	* Validates TCE address.
	92	* At the moment flags and page mask are validated.
	93	* As the host kernel does not access those addresses (just puts them
	94	* to the table and user space is supposed to process them), we can skip
	95	* checking other things (such as TCE is a guest RAM address or the page
	96	* was actually allocated).
	97	*
	98	* WARNING: This will be called in real-mode on HV KVM and virtual
	99	* mode on PR KVM
	100	*/
	101	long kvmppc_tce_validate(struct kvmppc_spapr_tce_table *stt, unsigned long tce)
	102	{
b1af23d8 AK	103	unsigned long gpa = tce & ~(TCE_PCI_READ \| TCE_PCI_WRITE);
	104	enum dma_data_direction dir = iommu_tce_direction(tce);
	105
	106	/* Allow userspace to poison TCE table */
	107	if (dir == DMA_NONE)
	108	return H_SUCCESS;
5ee7af18	109
b1af23d8	110	if (iommu_tce_check_gpa(stt->page_shift, gpa))
5ee7af18 AK	111	return H_PARAMETER;
	112
	113	return H_SUCCESS;
	114	}
	115	EXPORT_SYMBOL_GPL(kvmppc_tce_validate);
	116
	117	/* Note on the use of page_address() in real mode,
	118	*
	119	* It is safe to use page_address() in real mode on ppc64 because
	120	* page_address() is always defined as lowmem_page_address()
	121	* which returns __va(PFN_PHYS(page_to_pfn(page))) which is arithmetic
	122	* operation and does not access page struct.
	123	*
	124	* Theoretically page_address() could be defined different
	125	* but either WANT_PAGE_VIRTUAL or HASHED_PAGE_VIRTUAL
	126	* would have to be enabled.
	127	* WANT_PAGE_VIRTUAL is never enabled on ppc32/ppc64,
	128	* HASHED_PAGE_VIRTUAL could be enabled for ppc32 only and only
	129	* if CONFIG_HIGHMEM is defined. As CONFIG_SPARSEMEM_VMEMMAP
	130	* is not expected to be enabled on ppc32, page_address()
	131	* is safe for ppc32 as well.
	132	*
	133	* WARNING: This will be called in real-mode on HV KVM and virtual
	134	* mode on PR KVM
	135	*/
	136	static u64 kvmppc_page_address(struct page page)
	137	{
	138	#if defined(HASHED_PAGE_VIRTUAL) \|\| defined(WANT_PAGE_VIRTUAL)
	139	#error TODO: fix to avoid page_address() here
	140	#endif
	141	return (u64 *) page_address(page);
	142	}
	143
	144	/*
	145	* Handles TCE requests for emulated devices.
	146	* Puts guest TCE values to the table and expects user space to convert them.
	147	* Called in both real and virtual modes.
	148	* Cannot fail so kvmppc_tce_validate must be called before it.
	149	*
	150	* WARNING: This will be called in real-mode on HV KVM and virtual
	151	* mode on PR KVM
	152	*/
	153	void kvmppc_tce_put(struct kvmppc_spapr_tce_table *stt,
	154	unsigned long idx, unsigned long tce)
	155	{
	156	struct page *page;
	157	u64 *tbl;
	158
14f853f1	159	idx -= stt->offset;
5ee7af18 AK	160	page = stt->pages[idx / TCES_PER_PAGE];
	161	tbl = kvmppc_page_address(page);
	162
	163	tbl[idx % TCES_PER_PAGE] = tce;
	164	}
	165	EXPORT_SYMBOL_GPL(kvmppc_tce_put);
fcbb2ce6	166
d3695aa4 AK	167	long kvmppc_gpa_to_ua(struct kvm *kvm, unsigned long gpa,
	168	unsigned long ua, unsigned long *prmap)
	169	{
	170	unsigned long gfn = gpa >> PAGE_SHIFT;
	171	struct kvm_memory_slot *memslot;
	172
	173	memslot = search_memslots(kvm_memslots(kvm), gfn);
	174	if (!memslot)
	175	return -EINVAL;
	176
	177	*ua = __gfn_to_hva_memslot(memslot, gfn) \|
	178	(gpa & ~(PAGE_MASK \| TCE_PCI_READ \| TCE_PCI_WRITE));
	179
	180	#ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
	181	if (prmap)
	182	*prmap = &memslot->arch.rmap[gfn - memslot->base_gfn];
	183	#endif
	184
	185	return 0;
	186	}
	187	EXPORT_SYMBOL_GPL(kvmppc_gpa_to_ua);
	188
	189	#ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
121f80ba AK	190	static void kvmppc_rm_clear_tce(struct iommu_table *tbl, unsigned long entry)
	191	{
	192	unsigned long hpa = 0;
	193	enum dma_data_direction dir = DMA_NONE;
	194
	195	iommu_tce_xchg_rm(tbl, entry, &hpa, &dir);
	196	}
	197
	198	static long kvmppc_rm_tce_iommu_mapped_dec(struct kvm *kvm,
	199	struct iommu_table *tbl, unsigned long entry)
	200	{
	201	struct mm_iommu_table_group_mem_t *mem = NULL;
	202	const unsigned long pgsize = 1ULL << tbl->it_page_shift;
	203	unsigned long *pua = IOMMU_TABLE_USERSPACE_ENTRY(tbl, entry);
	204
	205	if (!pua)
	206	/* it_userspace allocation might be delayed */
	207	return H_TOO_HARD;
	208
	209	pua = (void *) vmalloc_to_phys(pua);
	210	if (WARN_ON_ONCE_RM(!pua))
	211	return H_HARDWARE;
	212
	213	mem = mm_iommu_lookup_rm(kvm->mm, *pua, pgsize);
	214	if (!mem)
	215	return H_TOO_HARD;
	216
	217	mm_iommu_mapped_dec(mem);
	218
	219	*pua = 0;
	220
	221	return H_SUCCESS;
	222	}
	223
	224	static long kvmppc_rm_tce_iommu_unmap(struct kvm *kvm,
	225	struct iommu_table *tbl, unsigned long entry)
	226	{
	227	enum dma_data_direction dir = DMA_NONE;
	228	unsigned long hpa = 0;
	229	long ret;
	230
	231	if (iommu_tce_xchg_rm(tbl, entry, &hpa, &dir))
	232	/*
	233	* real mode xchg can fail if struct page crosses
	234	* a page boundary
	235	*/
	236	return H_TOO_HARD;
	237
	238	if (dir == DMA_NONE)
	239	return H_SUCCESS;
	240
	241	ret = kvmppc_rm_tce_iommu_mapped_dec(kvm, tbl, entry);
	242	if (ret)
	243	iommu_tce_xchg_rm(tbl, entry, &hpa, &dir);
	244
	245	return ret;
	246	}
	247
	248	static long kvmppc_rm_tce_iommu_map(struct kvm kvm, struct iommu_table tbl,
	249	unsigned long entry, unsigned long ua,
	250	enum dma_data_direction dir)
	251	{
	252	long ret;
	253	unsigned long hpa = 0;
254	unsigned long *pua = IOMMU_TABLE_USERSPACE_ENTRY(tbl, entry);
255	struct mm_iommu_table_group_mem_t *mem;
256
257	if (!pua)
258	/* it_userspace allocation might be delayed */
259	return H_TOO_HARD;
260
261	mem = mm_iommu_lookup_rm(kvm->mm, ua, 1ULL << tbl->it_page_shift);
262	if (!mem)
263	return H_TOO_HARD;
264
265	if (WARN_ON_ONCE_RM(mm_iommu_ua_to_hpa_rm(mem, ua, &hpa)))
266	return H_HARDWARE;
267
268	pua = (void *) vmalloc_to_phys(pua);
269	if (WARN_ON_ONCE_RM(!pua))
270	return H_HARDWARE;
271
272	if (WARN_ON_ONCE_RM(mm_iommu_mapped_inc(mem)))
273	return H_CLOSED;
274
275	ret = iommu_tce_xchg_rm(tbl, entry, &hpa, &dir);
276	if (ret) {
277	mm_iommu_mapped_dec(mem);
278	/*
279	* real mode xchg can fail if struct page crosses
280	* a page boundary
281	*/
282	return H_TOO_HARD;
283	}
284
285	if (dir != DMA_NONE)
286	kvmppc_rm_tce_iommu_mapped_dec(kvm, tbl, entry);
287
288	*pua = ua;
289
290	return 0;
291	}
292
31217db7 AK	293	long kvmppc_rm_h_put_tce(struct kvm_vcpu *vcpu, unsigned long liobn,
31217db7 AK	294	unsigned long ioba, unsigned long tce)
54738c09	295	{
503bfcbe	296	struct kvmppc_spapr_tce_table *stt;
fcbb2ce6	297	long ret;
121f80ba AK	298	struct kvmppc_spapr_tce_iommu_table *stit;
	299	unsigned long entry, ua = 0;
	300	enum dma_data_direction dir;
54738c09 DG	301
	302	/* udbg_printf("H_PUT_TCE(): liobn=0x%lx ioba=0x%lx, tce=0x%lx\n", */
	303	/* liobn, ioba, tce); */
	304
acde2572 PM	305	/* For radix, we might be in virtual mode, so punt */
	306	if (kvm_is_radix(vcpu->kvm))
	307	return H_TOO_HARD;
	308
503bfcbe	309	stt = kvmppc_find_table(vcpu->kvm, liobn);
fcbb2ce6 AK	310	if (!stt)
	311	return H_TOO_HARD;
	312
	313	ret = kvmppc_ioba_validate(stt, ioba, 1);
	314	if (ret != H_SUCCESS)
	315	return ret;
	316
5ee7af18 AK	317	ret = kvmppc_tce_validate(stt, tce);
	318	if (ret != H_SUCCESS)
	319	return ret;
fcbb2ce6	320
121f80ba AK	321	dir = iommu_tce_direction(tce);
	322	if ((dir != DMA_NONE) && kvmppc_gpa_to_ua(vcpu->kvm,
	323	tce & ~(TCE_PCI_READ \| TCE_PCI_WRITE), &ua, NULL))
	324	return H_PARAMETER;
	325
	326	entry = ioba >> stt->page_shift;
	327
	328	list_for_each_entry_lockless(stit, &stt->iommu_tables, next) {
	329	if (dir == DMA_NONE)
	330	ret = kvmppc_rm_tce_iommu_unmap(vcpu->kvm,
	331	stit->tbl, entry);
	332	else
	333	ret = kvmppc_rm_tce_iommu_map(vcpu->kvm,
	334	stit->tbl, entry, ua, dir);
	335
	336	if (ret == H_SUCCESS)
	337	continue;
	338
	339	if (ret == H_TOO_HARD)
	340	return ret;
	341
	342	WARN_ON_ONCE_RM(1);
	343	kvmppc_rm_clear_tce(stit->tbl, entry);
	344	}
	345
	346	kvmppc_tce_put(stt, entry, tce);
fcbb2ce6 AK	347
fcbb2ce6 AK	348	return H_SUCCESS;
54738c09	349	}
69e9fbb2	350
d3695aa4 AK	351	static long kvmppc_rm_ua_to_hpa(struct kvm_vcpu *vcpu,
	352	unsigned long ua, unsigned long *phpa)
	353	{
	354	pte_t *ptep, pte;
	355	unsigned shift = 0;
	356
94171b19 AK	357	/*
	358	* Called in real mode with MSR_EE = 0. We are safe here.
	359	* It is ok to do the lookup with arch.pgdir here, because
	360	* we are doing this on secondary cpus and current task there
	361	* is not the hypervisor. Also this is safe against THP in the
	362	* host, because an IPI to primary thread will wait for the secondary
	363	* to exit which will agains result in the below page table walk
	364	* to finish.
	365	*/
	366	ptep = __find_linux_pte(vcpu->arch.pgdir, ua, NULL, &shift);
d3695aa4 AK	367	if (!ptep \|\| !pte_present(*ptep))
	368	return -ENXIO;
	369	pte = *ptep;
	370
	371	if (!shift)
	372	shift = PAGE_SHIFT;
	373
	374	/* Avoid handling anything potentially complicated in realmode */
	375	if (shift > PAGE_SHIFT)
	376	return -EAGAIN;
	377
	378	if (!pte_young(pte))
	379	return -EAGAIN;
	380
	381	*phpa = (pte_pfn(pte) << PAGE_SHIFT) \| (ua & ((1ULL << shift) - 1)) \|
	382	(ua & ~PAGE_MASK);
	383
	384	return 0;
	385	}
	386
	387	long kvmppc_rm_h_put_tce_indirect(struct kvm_vcpu *vcpu,
	388	unsigned long liobn, unsigned long ioba,
	389	unsigned long tce_list, unsigned long npages)
	390	{
	391	struct kvmppc_spapr_tce_table *stt;
	392	long i, ret = H_SUCCESS;
	393	unsigned long tces, entry, ua = 0;
	394	unsigned long *rmap = NULL;
da6f59e1	395	bool prereg = false;
121f80ba	396	struct kvmppc_spapr_tce_iommu_table *stit;
d3695aa4	397
acde2572 PM	398	/* For radix, we might be in virtual mode, so punt */
	399	if (kvm_is_radix(vcpu->kvm))
	400	return H_TOO_HARD;
	401
503bfcbe	402	stt = kvmppc_find_table(vcpu->kvm, liobn);
d3695aa4 AK	403	if (!stt)
	404	return H_TOO_HARD;
	405
fe26e527	406	entry = ioba >> stt->page_shift;
d3695aa4 AK	407	/*
	408	* The spec says that the maximum size of the list is 512 TCEs
	409	* so the whole table addressed resides in 4K page
	410	*/
	411	if (npages > 512)
	412	return H_PARAMETER;
	413
	414	if (tce_list & (SZ_4K - 1))
	415	return H_PARAMETER;
	416
	417	ret = kvmppc_ioba_validate(stt, ioba, npages);
	418	if (ret != H_SUCCESS)
	419	return ret;
	420
da6f59e1 AK	421	if (mm_iommu_preregistered(vcpu->kvm->mm)) {
	422	/*
	423	* We get here if guest memory was pre-registered which
	424	* is normally VFIO case and gpa->hpa translation does not
	425	* depend on hpt.
	426	*/
	427	struct mm_iommu_table_group_mem_t *mem;
d3695aa4	428
da6f59e1 AK	429	if (kvmppc_gpa_to_ua(vcpu->kvm, tce_list, &ua, NULL))
da6f59e1 AK	430	return H_TOO_HARD;
d3695aa4	431
da6f59e1 AK	432	mem = mm_iommu_lookup_rm(vcpu->kvm->mm, ua, IOMMU_PAGE_SIZE_4K);
	433	if (mem)
	434	prereg = mm_iommu_ua_to_hpa_rm(mem, ua, &tces) == 0;
	435	}
	436
	437	if (!prereg) {
	438	/*
	439	* This is usually a case of a guest with emulated devices only
	440	* when TCE list is not in preregistered memory.
	441	* We do not require memory to be preregistered in this case
	442	* so lock rmap and do __find_linux_pte_or_hugepte().
	443	*/
	444	if (kvmppc_gpa_to_ua(vcpu->kvm, tce_list, &ua, &rmap))
	445	return H_TOO_HARD;
	446
	447	rmap = (void *) vmalloc_to_phys(rmap);
121f80ba AK	448	if (WARN_ON_ONCE_RM(!rmap))
121f80ba AK	449	return H_HARDWARE;
da6f59e1 AK	450
	451	/*
	452	* Synchronize with the MMU notifier callbacks in
39c983ea	453	* book3s_64_mmu_hv.c (kvm_unmap_hva_range_hv etc.).
da6f59e1 AK	454	* While we have the rmap lock, code running on other CPUs
	455	* cannot finish unmapping the host real page that backs
	456	* this guest real page, so we are OK to access the host
	457	* real page.
	458	*/
	459	lock_rmap(rmap);
	460	if (kvmppc_rm_ua_to_hpa(vcpu, ua, &tces)) {
	461	ret = H_TOO_HARD;
	462	goto unlock_exit;
	463	}
d3695aa4 AK	464	}
	465
	466	for (i = 0; i < npages; ++i) {
	467	unsigned long tce = be64_to_cpu(((u64 *)tces)[i]);
	468
	469	ret = kvmppc_tce_validate(stt, tce);
	470	if (ret != H_SUCCESS)
	471	goto unlock_exit;
	472
121f80ba AK	473	ua = 0;
	474	if (kvmppc_gpa_to_ua(vcpu->kvm,
	475	tce & ~(TCE_PCI_READ \| TCE_PCI_WRITE),
	476	&ua, NULL))
	477	return H_PARAMETER;
	478
	479	list_for_each_entry_lockless(stit, &stt->iommu_tables, next) {
	480	ret = kvmppc_rm_tce_iommu_map(vcpu->kvm,
	481	stit->tbl, entry + i, ua,
	482	iommu_tce_direction(tce));
	483
	484	if (ret == H_SUCCESS)
	485	continue;
	486
	487	if (ret == H_TOO_HARD)
	488	goto unlock_exit;
	489
	490	WARN_ON_ONCE_RM(1);
	491	kvmppc_rm_clear_tce(stit->tbl, entry);
	492	}
	493
d3695aa4 AK	494	kvmppc_tce_put(stt, entry + i, tce);
	495	}
	496
	497	unlock_exit:
da6f59e1 AK	498	if (rmap)
da6f59e1 AK	499	unlock_rmap(rmap);
d3695aa4 AK	500
	501	return ret;
	502	}
	503
31217db7	504	long kvmppc_rm_h_stuff_tce(struct kvm_vcpu *vcpu,
d3695aa4 AK	505	unsigned long liobn, unsigned long ioba,
	506	unsigned long tce_value, unsigned long npages)
	507	{
	508	struct kvmppc_spapr_tce_table *stt;
	509	long i, ret;
121f80ba	510	struct kvmppc_spapr_tce_iommu_table *stit;
d3695aa4	511
acde2572 PM	512	/* For radix, we might be in virtual mode, so punt */
	513	if (kvm_is_radix(vcpu->kvm))
	514	return H_TOO_HARD;
	515
503bfcbe	516	stt = kvmppc_find_table(vcpu->kvm, liobn);
d3695aa4 AK	517	if (!stt)
	518	return H_TOO_HARD;
	519
	520	ret = kvmppc_ioba_validate(stt, ioba, npages);
	521	if (ret != H_SUCCESS)
	522	return ret;
	523
	524	/* Check permission bits only to allow userspace poison TCE for debug */
	525	if (tce_value & (TCE_PCI_WRITE \| TCE_PCI_READ))
	526	return H_PARAMETER;
	527
121f80ba AK	528	list_for_each_entry_lockless(stit, &stt->iommu_tables, next) {
	529	unsigned long entry = ioba >> stit->tbl->it_page_shift;
	530
	531	for (i = 0; i < npages; ++i) {
	532	ret = kvmppc_rm_tce_iommu_unmap(vcpu->kvm,
	533	stit->tbl, entry + i);
	534
	535	if (ret == H_SUCCESS)
	536	continue;
	537
	538	if (ret == H_TOO_HARD)
	539	return ret;
	540
	541	WARN_ON_ONCE_RM(1);
	542	kvmppc_rm_clear_tce(stit->tbl, entry);
	543	}
	544	}
	545
fe26e527 AK	546	for (i = 0; i < npages; ++i, ioba += (1ULL << stt->page_shift))
fe26e527 AK	547	kvmppc_tce_put(stt, ioba >> stt->page_shift, tce_value);
d3695aa4 AK	548
	549	return H_SUCCESS;
	550	}
d3695aa4	551
acde2572	552	/* This can be called in either virtual mode or real mode */
69e9fbb2 LD	553	long kvmppc_h_get_tce(struct kvm_vcpu *vcpu, unsigned long liobn,
	554	unsigned long ioba)
	555	{
503bfcbe	556	struct kvmppc_spapr_tce_table *stt;
fcbb2ce6 AK	557	long ret;
	558	unsigned long idx;
	559	struct page *page;
	560	u64 *tbl;
69e9fbb2	561
503bfcbe	562	stt = kvmppc_find_table(vcpu->kvm, liobn);
fcbb2ce6 AK	563	if (!stt)
fcbb2ce6 AK	564	return H_TOO_HARD;
69e9fbb2	565
fcbb2ce6 AK	566	ret = kvmppc_ioba_validate(stt, ioba, 1);
	567	if (ret != H_SUCCESS)
	568	return ret;
69e9fbb2	569
14f853f1	570	idx = (ioba >> stt->page_shift) - stt->offset;
fcbb2ce6 AK	571	page = stt->pages[idx / TCES_PER_PAGE];
fcbb2ce6 AK	572	tbl = (u64 *)page_address(page);
69e9fbb2	573
fcbb2ce6	574	vcpu->arch.gpr[4] = tbl[idx % TCES_PER_PAGE];
69e9fbb2	575
fcbb2ce6	576	return H_SUCCESS;
69e9fbb2 LD	577	}
69e9fbb2 LD	578	EXPORT_SYMBOL_GPL(kvmppc_h_get_tce);
d3695aa4 AK	579
d3695aa4 AK	580	#endif /* KVM_BOOK3S_HV_POSSIBLE */