/*
* 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.
*
* Copyright 2010-2011 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com>
*/
#include <linux/types.h>
#include <linux/string.h>
#include <linux/kvm.h>
#include <linux/kvm_host.h>
#include <linux/hugetlb.h>
#include <linux/module.h>
#include <asm/tlbflush.h>
#include <asm/kvm_ppc.h>
#include <asm/kvm_book3s.h>
#include <asm/mmu-hash64.h>
#include <asm/hvcall.h>
#include <asm/synch.h>
#include <asm/ppc-opcode.h>
/* Translate address of a vmalloc'd thing to a linear map address */
static void *real_vmalloc_addr(void *x)
{
unsigned long addr = (unsigned long) x;
pte_t *p;
/*
* assume we don't have huge pages in vmalloc space...
* So don't worry about THP collapse/split. Called
* Only in realmode, hence won't need irq_save/restore.
*/
p = __find_linux_pte_or_hugepte(swapper_pg_dir, addr, NULL);
if (!p || !pte_present(*p))
return NULL;
addr = (pte_pfn(*p) << PAGE_SHIFT) | (addr & ~PAGE_MASK);
return __va(addr);
}
/* Return 1 if we need to do a global tlbie, 0 if we can use tlbiel */
static int global_invalidates(struct kvm *kvm, unsigned long flags)
{
int global;
/*
* If there is only one vcore, and it's currently running,
* as indicated by local_paca->kvm_hstate.kvm_vcpu being set,
* we can use tlbiel as long as we mark all other physical
* cores as potentially having stale TLB entries for this lpid.
* Otherwise, don't use tlbiel.
*/
if (kvm->arch.online_vcores == 1 && local_paca->kvm_hstate.kvm_vcpu)
global = 0;
else
global = 1;
if (!global) {
/* any other core might now have stale TLB entries... */
smp_wmb();
cpumask_setall(&kvm->arch.need_tlb_flush);
cpumask_clear_cpu(local_paca->kvm_hstate.kvm_vcore->pcpu,
&kvm->arch.need_tlb_flush);
}
return global;
}
/*
* Add this HPTE into the chain for the real page.
* Must be called with the chain locked; it unlocks the chain.
*/
void kvmppc_add_revmap_chain(struct kvm *kvm, struct revmap_entry *rev,
unsigned long *rmap, long pte_index, int realmode)
{
struct revmap_entry *head, *tail;
unsigned long i;
if (*rmap & KVMPPC_RMAP_PRESENT) {
i = *rmap & KVMPPC_RMAP_INDEX;
head = &kvm->arch.revmap[i];
if (realmode)
head = real_vmalloc_addr(head);
tail = &kvm->arch.revmap[head->back];
if (realmode)
tail = real_vmalloc_addr(tail);
rev->forw = i;
rev->back = head->back;
tail->forw = pte_index;
head->back = pte_index;
} else {
rev->forw = rev->back = pte_index;
*rmap = (*rmap & ~KVMPPC_RMAP_INDEX) |
pte_index | KVMPPC_RMAP_PRESENT;
}
unlock_rmap(rmap);
}
EXPORT_SYMBOL_GPL(kvmppc_add_revmap_chain);
/* Remove this HPTE from the chain for a real page */
static void remove_revmap_chain(struct kvm *kvm, long pte_index,
struct revmap_entry *rev,
unsigned long hpte_v, unsigned long hpte_r)
{
struct revmap_entry *next, *prev;
unsigned long gfn, ptel, head;
struct kvm_memory_slot *memslot;
unsigned long *rmap;
unsigned long rcbits;
rcbits = hpte_r & (HPTE_R_R | HPTE_R_C);
ptel = rev->guest_rpte |= rcbits;
gfn = hpte_rpn(ptel, hpte_page_size(hpte_v, ptel));
memslot = __gfn_to_memslot(kvm_memslots_raw(kvm), gfn);
if (!memslot)
return;
rmap = real_vmalloc_addr(&memslot->arch.rmap[gfn - memslot->base_gfn]);
lock_rmap(rmap);
head = *rmap & KVMPPC_RMAP_INDEX;
next = real_vmalloc_addr(&kvm->arch.revmap[rev->forw]);
prev = real_vmalloc_addr(&kvm->arch.revmap[rev->back]);
next->back = rev->back;
prev->forw = rev->forw;
if (head == pte_index) {
head = rev->forw;
if (head == pte_index)
*rmap &= ~(KVMPPC_RMAP_PRESENT | KVMPPC_RMAP_INDEX);
else
*rmap = (*rmap & ~KVMPPC_RMAP_INDEX) | head;
}
*rmap |= rcbits << KVMPPC_RMAP_RC_SHIFT;
unlock_rmap(rmap);
}
long kvmppc_do_h_enter(struct kvm *kvm, unsigned long flags,
long pte_index, unsigned long pteh, unsigned long ptel,
pgd_t *pgdir, bool realmode, unsigned long *pte_idx_ret)
{
unsigned long i, pa, gpa, gfn, psize;
unsigned long slot_fn, hva;
__be64 *hpte;
struct revmap_entry *rev;
unsigned long g_ptel;
struct kvm_memory_slot *memslot;
unsigned hpage_shift;
unsigned long is_io;
unsigned long *rmap;
pte_t *ptep;
unsigned int writing;
unsigned long mmu_seq;
unsigned long rcbits, irq_flags = 0;
psize = hpte_page_size(pteh, ptel);
if (!psize)
return H_PARAMETER;
writing = hpte_is_writable(ptel);
pteh &= ~(HPTE_V_HVLOCK | HPTE_V_ABSENT | HPTE_V_VALID);
ptel &= ~HPTE_GR_RESERVED;
g_ptel = ptel;
/* used later to detect if we might have been invalidated */
mmu_seq = kvm->mmu_notifier_seq;
smp_rmb();
/* Find the memslot (if any) for this address */
gpa = (ptel & HPTE_R_RPN) & ~(psize - 1);
gfn = gpa >> PAGE_SHIFT;
memslot = __gfn_to_memslot(kvm_memslots_raw(kvm), gfn);
pa = 0;
is_io = ~0ul;
rmap = NULL;
if (!(memslot && !(memslot->flags & KVM_MEMSLOT_INVALID))) {
/* Emulated MMIO - mark this with key=31 */
pteh |= HPTE_V_ABSENT;
ptel |= HPTE_R_KEY_HI | HPTE_R_KEY_LO;
goto do_insert;
}
/* Check if the requested page fits entirely in the memslot. */
if (!slot_is_aligned(memslot, psize))
return H_PARAMETER;
slot_fn = gfn - memslot->base_gfn;
rmap = &memslot->arch.rmap[slot_fn];
/* Translate to host virtual address */
hva = __gfn_to_hva_memslot(memslot, gfn);
/*
* If we had a page table table change after lookup, we would
* retry via mmu_notifier_retry.
*/
if (realmode)
ptep = __find_linux_pte_or_hugepte(pgdir, hva, &hpage_shift);
else {
local_irq_save(irq_flags);
ptep = find_linux_pte_or_hugepte(pgdir, hva, &hpage_shift);
}
if (ptep) {
pte_t pte;
unsigned int host_pte_size;
if (hpage_shift)
host_pte_size = 1ul << hpage_shift;
else
host_pte_size = PAGE_SIZE;
/*
* We should always find the guest page size
* to <= host page size, if host is using hugepage
*/
if (host_pte_size < psize) {
if (!realmode)
local_irq_restore(flags);
return H_PARAMETER;
}
pte = kvmppc_read_update_linux_pte(ptep, writing);
if (pte_present(pte) && !pte_protnone(pte)) {
if (writing && !pte_write(pte))
/* make the actual HPTE be read-only */
ptel = hpte_make_readonly(ptel);
is_io = hpte_cache_bits(pte_val(pte));
pa = pte_pfn(pte) << PAGE_SHIFT;
pa |= hva & (host_pte_size - 1);
pa |= gpa & ~PAGE_MASK;
}
}
if (!realmode)
local_irq_restore(irq_flags);
ptel &= ~(HPTE_R_PP0 - psize);
ptel |= pa;
if (pa)
pteh |= HPTE_V_VALID;
else
pteh |= HPTE_V_ABSENT;
/* Check WIMG */
if (is_io != ~0ul && !hpte_cache_flags_ok(ptel, is_io)) {
if (is_io)
return H_PARAMETER;
/*
* Allow guest to map emulated device memory as
* uncacheable, but actually make it cacheable.
*/
ptel &= ~(HPTE_R_W|HPTE_R_I|HPTE_R_G);
ptel |= HPTE_R_M;
}
/* Find and lock the HPTEG slot to use */
do_insert:
if (pte_index >= kvm->arch.hpt_npte)
return H_PARAMETER;
if (likely((flags & H_EXACT) == 0)) {
pte_index &= ~7UL;
hpte = (__be64 *)(kvm->arch.hpt_virt + (pte_index << 4));
for (i = 0; i < 8; ++i) {
if ((be64_to_cpu(*hpte) & HPTE_V_VALID) == 0 &&
try_lock_hpte(hpte, HPTE_V_HVLOCK | HPTE_V_VALID |
HPTE_V_ABSENT))
break;
hpte += 2;
}
if (i == 8) {
/*
* Since try_lock_hpte doesn't retry (not even stdcx.
* failures), it could be that there is a free slot
* but we transiently failed to lock it. Try again,
* actually locking each slot and checking it.
*/
hpte -= 16;
for (i = 0; i < 8; ++i) {
u64 pte;
while (!try_lock_hpte(hpte, HPTE_V_HVLOCK))
cpu_relax();
pte = be64_to_cpu(hpte[0]);
if (!(pte & (HPTE_V_VALID | HPTE_V_ABSENT)))
break;
__unlock_hpte(hpte, pte);
hpte += 2;
}
if (i == 8)
return H_PTEG_FULL;
}
pte_index += i;
} else {
hpte = (__be64 *)(kvm->arch.hpt_virt + (pte_index << 4));
if (!try_lock_hpte(hpte, HPTE_V_HVLOCK | HPTE_V_VALID |
HPTE_V_ABSENT)) {
/* Lock the slot and check again */
u64 pte;
while (!try_lock_hpte(hpte, HPTE_V_HVLOCK))
cpu_relax();
pte = be64_to_cpu(hpte[0]);
if (pte & (HPTE_V_VALID | HPTE_V_ABSENT)) {
__unlock_hpte(hpte, pte);
return H_PTEG_FULL;
}
}
}
/* Save away the guest's idea of the second HPTE dword */
rev = &kvm->arch.revmap[pte_index];
if (realmode)
rev = real_vmalloc_addr(rev);
if (rev) {
rev->guest_rpte = g_ptel;
note_hpte_modification(kvm, rev);
}
/* Link HPTE into reverse-map chain */
if (pteh & HPTE_V_VALID) {
if (realmode)
rmap = real_vmalloc_addr(rmap);
lock_rmap(rmap);
/* Check for pending invalidations under the rmap chain lock */
if (mmu_notifier_retry(kvm, mmu_seq)) {
/* inval in progress, write a non-present HPTE */
pteh |= HPTE_V_ABSENT;
pteh &= ~HPTE_V_VALID;
unlock_rmap(rmap);
} else {
kvmppc_add_revmap_chain(kvm, rev, rmap, pte_index,
realmode);
/* Only set R/C in real HPTE if already set in *rmap */
rcbits = *rmap >> KVMPPC_RMAP_RC_SHIFT;
ptel &= rcbits | ~(HPTE_R_R | HPTE_R_C);
}
}
hpte[1] = cpu_to_be64(ptel);
/* Write the first HPTE dword, unlocking the HPTE and making it valid */
eieio();
__unlock_hpte(hpte, pteh);
asm volatile("ptesync" : : : "memory");
*pte_idx_ret = pte_index;
return H_SUCCESS;
}
EXPORT_SYMBOL_GPL(kvmppc_do_h_enter);
long kvmppc_h_enter(struct kvm_vcpu *vcpu, unsigned long flags,
long pte_index, unsigned long pteh, unsigned long ptel)
{
return kvmppc_do_h_enter(vcpu->kvm, flags, pte_index, pteh, ptel,
vcpu->arch.pgdir, true, &vcpu->arch.gpr[4]);
}
#ifdef __BIG_ENDIAN__
#define LOCK_TOKEN (*(u32 *)(&get_paca()->lock_token))
#else
#define LOCK_TOKEN (*(u32 *)(&get_paca()->paca_index))
#endif
static inline int try_lock_tlbie(unsigned int *lock)
{
unsigned int tmp, old;
unsigned int token = LOCK_TOKEN;
asm volatile("1:lwarx %1,0,%2\n"
" cmpwi cr0,%1,0\n"
" bne 2f\n"
" stwcx. %3,0,%2\n"
" bne- 1b\n"
" isync\n"
"2:"
: "=&r" (tmp), "=&r" (old)
: "r" (lock), "r" (token)
: "cc", "memory");
return old == 0;
}
static void do_tlbies(struct kvm *kvm, unsigned long *rbvalues,
long npages, int global, bool need_sync)
{
long i;
if (global) {
while (!try_lock_tlbie(&kvm->arch.tlbie_lock))
cpu_relax();
if (need_sync)
asm volatile("ptesync" : : : "memory");
for (i = 0; i < npages; ++i)
asm volatile(PPC_TLBIE(%1,%0) : :
"r" (rbvalues[i]), "r" (kvm->arch.lpid));
asm volatile("eieio; tlbsync; ptesync" : : : "memory");
kvm->arch.tlbie_lock = 0;
} else {
if (need_sync)
asm volatile("ptesync" : : : "memory");
for (i = 0; i < npages; ++i)
asm volatile("tlbiel %0" : : "r" (rbvalues[i]));
asm volatile("ptesync" : : : "memory");
}
}
long kvmppc_do_h_remove(struct kvm *kvm, unsigned long flags,
unsigned long pte_index, unsigned long avpn,
unsigned long *hpret)
{
__be64 *hpte;
unsigned long v, r, rb;
struct revmap_entry *rev;
u64 pte;
if (pte_index >= kvm->arch.hpt_npte)
return H_PARAMETER;
hpte = (__be64 *)(kvm->arch.hpt_virt + (pte_index << 4));
while (!try_lock_hpte(hpte, HPTE_V_HVLOCK))
cpu_relax();
pte = be64_to_cpu(hpte[0]);
if ((pte & (HPTE_V_ABSENT | HPTE_V_VALID)) == 0 ||
((flags & H_AVPN) && (pte & ~0x7fUL) != avpn) ||
((flags & H_ANDCOND) && (pte & avpn) != 0)) {
__unlock_hpte(hpte, pte);
return H_NOT_FOUND;
}
rev = real_vmalloc_addr(&kvm->arch.revmap[pte_index]);
v = pte & ~HPTE_V_HVLOCK;
if (v & HPTE_V_VALID) {
u64 pte1;
pte1 = be64_to_cpu(hpte[1]);
hpte[0] &= ~cpu_to_be64(HPTE_V_VALID);
rb = compute_tlbie_rb(v, pte1, pte_index);
do_tlbies(kvm, &rb, 1, global_invalidates(kvm, flags), true);
/* Read PTE low word after tlbie to get final R/C values */
remove_revmap_chain(kvm, pte_index, rev, v, pte1);
}
r = rev->guest_rpte & ~HPTE_GR_RESERVED;
note_hpte_modification(kvm, rev);
unlock_hpte(hpte, 0);
hpret[0] = v;
hpret[1] = r;
return H_SUCCESS;
}
EXPORT_SYMBOL_GPL(kvmppc_do_h_remove);
long kvmppc_h_remove(struct kvm_vcpu *vcpu, unsigned long flags,
unsigned long pte_index, unsigned long avpn)
{
return kvmppc_do_h_remove(vcpu->kvm, flags, pte_index, avpn,
&vcpu->arch.gpr[4]);
}
long kvmppc_h_bulk_remove(struct kvm_vcpu *vcpu)
{
struct kvm *kvm = vcpu->kvm;
unsigned long *args = &vcpu->arch.gpr[4];
__be64 *hp, *hptes[4];
unsigned long tlbrb[4];
long int i, j, k, n, found, indexes[4];
unsigned long flags, req, pte_index, rcbits;
int global;
long int ret = H_SUCCESS;
struct revmap_entry *rev, *revs[4];
u64 hp0;
global = global_invalidates(kvm, 0);
for (i = 0; i < 4 && ret == H_SUCCESS; ) {
n = 0;
for (; i < 4; ++i) {
j = i * 2;
pte_index = args[j];
flags = pte_index >> 56;
pte_index &= ((1ul << 56) - 1);
req = flags >> 6;
flags &= 3;
if (req == 3) { /* no more requests */
i = 4;
break;
}
if (req != 1 || flags == 3 ||
pte_index >= kvm->arch.hpt_npte) {
/* parameter error */
args[j] = ((0xa0 | flags) << 56) + pte_index;
ret = H_PARAMETER;
break;
}
hp = (__be64 *) (kvm->arch.hpt_virt + (pte_index << 4));
/* to avoid deadlock, don't spin except for first */
if (!try_lock_hpte(hp, HPTE_V_HVLOCK)) {
if (n)
break;
while (!try_lock_hpte(hp, HPTE_V_HVLOCK))
cpu_relax();
}
found = 0;
hp0 = be64_to_cpu(hp[0]);
if (hp0 & (HPTE_V_ABSENT | HPTE_V_VALID)) {
switch (flags & 3) {
case 0: /* absolute */
found = 1;
break;
case 1: /* andcond */
if (!(hp0 & args[j + 1]))
found = 1;
break;
case 2: /* AVPN */
if ((hp0 & ~0x7fUL) == args[j + 1])
found = 1;
break;
}
}
if (!found) {
hp[0] &= ~cpu_to_be64(HPTE_V_HVLOCK);
args[j] = ((0x90 | flags) << 56) + pte_index;
continue;
}
args[j] = ((0x80 | flags) << 56) + pte_index;
rev = real_vmalloc_addr(&kvm->arch.revmap[pte_index]);
note_hpte_modification(kvm, rev);
if (!(hp0 & HPTE_V_VALID)) {
/* insert R and C bits from PTE */
rcbits = rev->guest_rpte & (HPTE_R_R|HPTE_R_C);
args[j] |= rcbits << (56 - 5);
hp[0] = 0;
continue;
}
/* leave it locked */
hp[0] &= ~cpu_to_be64(HPTE_V_VALID);
tlbrb[n] = compute_tlbie_rb(be64_to_cpu(hp[0]),
be64_to_cpu(hp[1]), pte_index);
indexes[n] = j;
hptes[n] = hp;
revs[n] = rev;
++n;
}
if (!n)
break;
/* Now that we've collected a batch, do the tlbies */
do_tlbies(kvm, tlbrb, n, global, true);
/* Read PTE low words after tlbie to get final R/C values */
for (k = 0; k < n; ++k) {
j = indexes[k];
pte_index = args[j] & ((1ul << 56) - 1);
hp = hptes[k];
rev = revs[k];
remove_revmap_chain(kvm, pte_index, rev,
be64_to_cpu(hp[0]), be64_to_cpu(hp[1]));
rcbits = rev->guest_rpte & (HPTE_R_R|HPTE_R_C);
args[j] |= rcbits << (56 - 5);
__unlock_hpte(hp, 0);
}
}
return ret;
}
long kvmppc_h_protect(struct kvm_vcpu *vcpu, unsigned long flags,
unsigned long pte_index, unsigned long avpn,
unsigned long va)
{
struct kvm *kvm = vcpu->kvm;
__be64 *hpte;
struct revmap_entry *rev;
unsigned long v, r, rb, mask, bits;
u64 pte;
if (pte_index >= kvm->arch.hpt_npte)
return H_PARAMETER;
hpte = (__be64 *)(kvm->arch.hpt_virt + (pte_index << 4));
while (!try_lock_hpte(hpte, HPTE_V_HVLOCK))
cpu_relax();
pte = be64_to_cpu(hpte[0]);
if ((pte & (HPTE_V_ABSENT | HPTE_V_VALID)) == 0 ||
((flags & H_AVPN) && (pte & ~0x7fUL) != avpn)) {
__unlock_hpte(hpte, pte);
return H_NOT_FOUND;
}
v = pte;
bits = (flags << 55) & HPTE_R_PP0;
bits |= (flags << 48) & HPTE_R_KEY_HI;
bits |= flags & (HPTE_R_PP | HPTE_R_N | HPTE_R_KEY_LO);
/* Update guest view of 2nd HPTE dword */
mask = HPTE_R_PP0 | HPTE_R_PP | HPTE_R_N |
HPTE_R_KEY_HI | HPTE_R_KEY_LO;
rev = real_vmalloc_addr(&kvm->arch.revmap[pte_index]);
if (rev) {
r = (rev->guest_rpte & ~mask) | bits;
rev->guest_rpte = r;
note_hpte_modification(kvm, rev);
}
/* Update HPTE */
if (v & HPTE_V_VALID) {
/*
* If the page is valid, don't let it transition from
* readonly to writable. If it should be writable, we'll
* take a trap and let the page fault code sort it out.
*/
pte = be64_to_cpu(hpte[1]);
r = (pte & ~mask) | bits;
if (hpte_is_writable(r) && !hpte_is_writable(pte))
r = hpte_make_readonly(r);
/* If the PTE is changing, invalidate it first */
if (r != pte) {
rb = compute_tlbie_rb(v, r, pte_index);
hpte[0] = cpu_to_be64((v & ~HPTE_V_VALID) |
HPTE_V_ABSENT);
do_tlbies(kvm, &rb, 1, global_invalidates(kvm, flags),
true);
hpte[1] = cpu_to_be64(r);
}
}
unlock_hpte(hpte, v & ~HPTE_V_HVLOCK);
asm volatile("ptesync" : : : "memory");
return H_SUCCESS;
}
long kvmppc_h_read(struct kvm_vcpu *vcpu, unsigned long flags,
unsigned long pte_index)
{
struct kvm *kvm = vcpu->kvm;
__be64 *hpte;
unsigned long v, r;
int i, n = 1;
struct revmap_entry *rev = NULL;
if (pte_index >= kvm->arch.hpt_npte)
return H_PARAMETER;
if (flags & H_READ_4) {
pte_index &= ~3;
n = 4;
}
rev = real_vmalloc_addr(&kvm->arch.revmap[pte_index]);
for (i = 0; i < n; ++i, ++pte_index) {
hpte = (__be64 *)(kvm->arch.hpt_virt + (pte_index << 4));
v = be64_to_cpu(hpte[0]) & ~HPTE_V_HVLOCK;
r = be64_to_cpu(hpte[1]);
if (v & HPTE_V_ABSENT) {
v &= ~HPTE_V_ABSENT;
v |= HPTE_V_VALID;
}
if (v & HPTE_V_VALID) {
r = rev[i].guest_rpte | (r & (HPTE_R_R | HPTE_R_C));
r &= ~HPTE_GR_RESERVED;
}
vcpu->arch.gpr[4 + i * 2] = v;
vcpu->arch.gpr[5 + i * 2] = r;
}
return H_SUCCESS;
}
void kvmppc_invalidate_hpte(struct kvm *kvm, __be64 *hptep,
unsigned long pte_index)
{
unsigned long rb;
hptep[0] &= ~cpu_to_be64(HPTE_V_VALID);
rb = compute_tlbie_rb(be64_to_cpu(hptep[0]), be64_to_cpu(hptep[1]),
pte_index);
do_tlbies(kvm, &rb, 1, 1, true);
}
EXPORT_SYMBOL_GPL(kvmppc_invalidate_hpte);
void kvmppc_clear_ref_hpte(struct kvm *kvm, __be64 *hptep,
unsigned long pte_index)
{
unsigned long rb;
unsigned char rbyte;
rb = compute_tlbie_rb(be64_to_cpu(hptep[0]), be64_to_cpu(hptep[1]),
pte_index);
rbyte = (be64_to_cpu(hptep[1]) & ~HPTE_R_R) >> 8;
/* modify only the second-last byte, which contains the ref bit */
*((char *)hptep + 14) = rbyte;
do_tlbies(kvm, &rb, 1, 1, false);
}
EXPORT_SYMBOL_GPL(kvmppc_clear_ref_hpte);
static int slb_base_page_shift[4] = {
24, /* 16M */
16, /* 64k */
34, /* 16G */
20, /* 1M, unsupported */
};
/* When called from virtmode, this func should be protected by
* preempt_disable(), otherwise, the holding of HPTE_V_HVLOCK
* can trigger deadlock issue.
*/
long kvmppc_hv_find_lock_hpte(struct kvm *kvm, gva_t eaddr, unsigned long slb_v,
unsigned long valid)
{
unsigned int i;
unsigned int pshift;
unsigned long somask;
unsigned long vsid, hash;
unsigned long avpn;
__be64 *hpte;
unsigned long mask, val;
unsigned long v, r;
/* Get page shift, work out hash and AVPN etc. */
mask = SLB_VSID_B | HPTE_V_AVPN | HPTE_V_SECONDARY;
val = 0;
pshift = 12;
if (slb_v & SLB_VSID_L) {
mask |= HPTE_V_LARGE;
val |= HPTE_V_LARGE;
pshift = slb_base_page_shift[(slb_v & SLB_VSID_LP) >> 4];
}
if (slb_v & SLB_VSID_B_1T) {
somask = (1UL << 40) - 1;
vsid = (slb_v & ~SLB_VSID_B) >> SLB_VSID_SHIFT_1T;
vsid ^= vsid << 25;
} else {
somask = (1UL << 28) - 1;
vsid = (slb_v & ~SLB_VSID_B) >> SLB_VSID_SHIFT;
}
hash = (vsid ^ ((eaddr & somask) >> pshift)) & kvm->arch.hpt_mask;
avpn = slb_v & ~(somask >> 16); /* also includes B */
avpn |= (eaddr & somask) >> 16;
if (pshift >= 24)
avpn &= ~((1UL << (pshift - 16)) - 1);
else
avpn &= ~0x7fUL;
val |= avpn;
for (;;) {
hpte = (__be64 *)(kvm->arch.hpt_virt + (hash << 7));
for (i = 0; i < 16; i += 2) {
/* Read the PTE racily */
v = be64_to_cpu(hpte[i]) & ~HPTE_V_HVLOCK;
/* Check valid/absent, hash, segment size and AVPN */
if (!(v & valid) || (v & mask) != val)
continue;
/* Lock the PTE and read it under the lock */
while (!try_lock_hpte(&hpte[i], HPTE_V_HVLOCK))
cpu_relax();
v = be64_to_cpu(hpte[i]) & ~HPTE_V_HVLOCK;
r = be64_to_cpu(hpte[i+1]);
/*
* Check the HPTE again, including base page size
*/
if ((v & valid) && (v & mask) == val &&
hpte_base_page_size(v, r) == (1ul << pshift))
/* Return with the HPTE still locked */
return (hash << 3) + (i >> 1);
__unlock_hpte(&hpte[i], v);
}
if (val & HPTE_V_SECONDARY)
break;
val |= HPTE_V_SECONDARY;
hash = hash ^ kvm->arch.hpt_mask;
}
return -1;
}
EXPORT_SYMBOL(kvmppc_hv_find_lock_hpte);
/*
* Called in real mode to check whether an HPTE not found fault
* is due to accessing a paged-out page or an emulated MMIO page,
* or if a protection fault is due to accessing a page that the
* guest wanted read/write access to but which we made read-only.
* Returns a possibly modified status (DSISR) value if not
* (i.e. pass the interrupt to the guest),
* -1 to pass the fault up to host kernel mode code, -2 to do that
* and also load the instruction word (for MMIO emulation),
* or 0 if we should make the guest retry the access.
*/
long kvmppc_hpte_hv_fault(struct kvm_vcpu *vcpu, unsigned long addr,
unsigned long slb_v, unsigned int status, bool data)
{
struct kvm *kvm = vcpu->kvm;
long int index;
unsigned long v, r, gr;
__be64 *hpte;
unsigned long valid;
struct revmap_entry *rev;
unsigned long pp, key;
/* For protection fault, expect to find a valid HPTE */
valid = HPTE_V_VALID;
if (status & DSISR_NOHPTE)
valid |= HPTE_V_ABSENT;
index = kvmppc_hv_find_lock_hpte(kvm, addr, slb_v, valid);
if (index < 0) {
if (status & DSISR_NOHPTE)
return status; /* there really was no HPTE */
return 0; /* for prot fault, HPTE disappeared */
}
hpte = (__be64 *)(kvm->arch.hpt_virt + (index << 4));
v = be64_to_cpu(hpte[0]) & ~HPTE_V_HVLOCK;
r = be64_to_cpu(hpte[1]);
rev = real_vmalloc_addr(&kvm->arch.revmap[index]);
gr = rev->guest_rpte;
unlock_hpte(hpte, v);
/* For not found, if the HPTE is valid by now, retry the instruction */
if ((status & DSISR_NOHPTE) && (v & HPTE_V_VALID))
return 0;
/* Check access permissions to the page */
pp = gr & (HPTE_R_PP0 | HPTE_R_PP);
key = (vcpu->arch.shregs.msr & MSR_PR) ? SLB_VSID_KP : SLB_VSID_KS;
status &= ~DSISR_NOHPTE; /* DSISR_NOHPTE == SRR1_ISI_NOPT */
if (!data) {
if (gr & (HPTE_R_N | HPTE_R_G))
return status | SRR1_ISI_N_OR_G;
if (!hpte_read_permission(pp, slb_v & key))
return status | SRR1_ISI_PROT;
} else if (status & DSISR_ISSTORE) {
/* check write permission */
if (!hpte_write_permission(pp, slb_v & key))
return status | DSISR_PROTFAULT;
} else {
if (!hpte_read_permission(pp, slb_v & key))
return status | DSISR_PROTFAULT;
}
/* Check storage key, if applicable */
if (data && (vcpu->arch.shregs.msr & MSR_DR)) {
unsigned int perm = hpte_get_skey_perm(gr, vcpu->arch.amr);
if (status & DSISR_ISSTORE)
perm >>= 1;
if (perm & 1)
return status | DSISR_KEYFAULT;
}
/* Save HPTE info for virtual-mode handler */
vcpu->arch.pgfault_addr = addr;
vcpu->arch.pgfault_index = index;
vcpu->arch.pgfault_hpte[0] = v;
vcpu->arch.pgfault_hpte[1] = r;
/* Check the storage key to see if it is possibly emulated MMIO */
if (data && (vcpu->arch.shregs.msr & MSR_IR) &&
(r & (HPTE_R_KEY_HI | HPTE_R_KEY_LO)) ==
(HPTE_R_KEY_HI | HPTE_R_KEY_LO))
return -2; /* MMIO emulation - load instr word */
return -1; /* send fault up to host kernel mode */
}
