linux/arch/powerpc/kvm/book3s_hv_rm_mmu.c
Paul Mackerras c43c3a8683 KVM: PPC: Book3S HV: Cleanups - constify memslots, fix comments
This adds 'const' to the declarations for the struct kvm_memory_slot
pointer parameters of some functions, which will make it possible to
call those functions from kvmppc_core_commit_memory_region_hv()
in the next patch.

This also fixes some comments about locking.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Reviewed-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-12-17 10:58:43 +11:00

1154 lines
31 KiB
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.
*
* 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 <linux/log2.h>
#include <asm/trace.h>
#include <asm/kvm_ppc.h>
#include <asm/kvm_book3s.h>
#include <asm/book3s/64/mmu-hash.h>
#include <asm/hvcall.h>
#include <asm/synch.h>
#include <asm/ppc-opcode.h>
#include <asm/pte-walk.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 with MSR_EE = 0, hence won't need irq_save/restore.
*/
p = find_init_mm_pte(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)
{
int global;
int cpu;
/*
* 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);
cpu = local_paca->kvm_hstate.kvm_vcore->pcpu;
/*
* On POWER9, threads are independent but the TLB is shared,
* so use the bit for the first thread to represent the core.
*/
if (cpu_has_feature(CPU_FTR_ARCH_300))
cpu = cpu_first_thread_sibling(cpu);
cpumask_clear_cpu(cpu, &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.hpt.rev[i];
if (realmode)
head = real_vmalloc_addr(head);
tail = &kvm->arch.hpt.rev[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);
/* Update the dirty bitmap of a memslot */
void kvmppc_update_dirty_map(const struct kvm_memory_slot *memslot,
unsigned long gfn, unsigned long psize)
{
unsigned long npages;
if (!psize || !memslot->dirty_bitmap)
return;
npages = (psize + PAGE_SIZE - 1) / PAGE_SIZE;
gfn -= memslot->base_gfn;
set_dirty_bits_atomic(memslot->dirty_bitmap, gfn, npages);
}
EXPORT_SYMBOL_GPL(kvmppc_update_dirty_map);
static void kvmppc_set_dirty_from_hpte(struct kvm *kvm,
unsigned long hpte_v, unsigned long hpte_gr)
{
struct kvm_memory_slot *memslot;
unsigned long gfn;
unsigned long psize;
psize = kvmppc_actual_pgsz(hpte_v, hpte_gr);
gfn = hpte_rpn(hpte_gr, psize);
memslot = __gfn_to_memslot(kvm_memslots_raw(kvm), gfn);
if (memslot && memslot->dirty_bitmap)
kvmppc_update_dirty_map(memslot, gfn, psize);
}
/* Returns a pointer to the revmap entry for the page mapped by a HPTE */
static unsigned long *revmap_for_hpte(struct kvm *kvm, unsigned long hpte_v,
unsigned long hpte_gr,
struct kvm_memory_slot **memslotp,
unsigned long *gfnp)
{
struct kvm_memory_slot *memslot;
unsigned long *rmap;
unsigned long gfn;
gfn = hpte_rpn(hpte_gr, kvmppc_actual_pgsz(hpte_v, hpte_gr));
memslot = __gfn_to_memslot(kvm_memslots_raw(kvm), gfn);
if (memslotp)
*memslotp = memslot;
if (gfnp)
*gfnp = gfn;
if (!memslot)
return NULL;
rmap = real_vmalloc_addr(&memslot->arch.rmap[gfn - memslot->base_gfn]);
return rmap;
}
/* 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 ptel, head;
unsigned long *rmap;
unsigned long rcbits;
struct kvm_memory_slot *memslot;
unsigned long gfn;
rcbits = hpte_r & (HPTE_R_R | HPTE_R_C);
ptel = rev->guest_rpte |= rcbits;
rmap = revmap_for_hpte(kvm, hpte_v, ptel, &memslot, &gfn);
if (!rmap)
return;
lock_rmap(rmap);
head = *rmap & KVMPPC_RMAP_INDEX;
next = real_vmalloc_addr(&kvm->arch.hpt.rev[rev->forw]);
prev = real_vmalloc_addr(&kvm->arch.hpt.rev[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;
if (rcbits & HPTE_R_C)
kvmppc_update_dirty_map(memslot, gfn,
kvmppc_actual_pgsz(hpte_v, hpte_r));
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;
bool is_ci;
unsigned long *rmap;
pte_t *ptep;
unsigned int writing;
unsigned long mmu_seq;
unsigned long rcbits, irq_flags = 0;
if (kvm_is_radix(kvm))
return H_FUNCTION;
psize = kvmppc_actual_pgsz(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_ci = false;
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)
local_irq_save(irq_flags);
/*
* If called in real mode we have MSR_EE = 0. Otherwise
* we disable irq above.
*/
ptep = __find_linux_pte(pgdir, hva, NULL, &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_ci = pte_ci(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_KEY | HPTE_R_PP0 | (psize-1);
ptel |= pa;
if (pa)
pteh |= HPTE_V_VALID;
else {
pteh |= HPTE_V_ABSENT;
ptel &= ~(HPTE_R_KEY_HI | HPTE_R_KEY_LO);
}
/*If we had host pte mapping then Check WIMG */
if (ptep && !hpte_cache_flags_ok(ptel, is_ci)) {
if (is_ci)
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 >= kvmppc_hpt_npte(&kvm->arch.hpt))
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.hpt.rev[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;
ptel &= ~(HPTE_R_KEY_HI | HPTE_R_KEY_LO);
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);
}
}
/* Convert to new format on P9 */
if (cpu_has_feature(CPU_FTR_ARCH_300)) {
ptel = hpte_old_to_new_r(pteh, ptel);
pteh = hpte_old_to_new_v(pteh);
}
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.regs.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 is_mmio_hpte(unsigned long v, unsigned long r)
{
return ((v & HPTE_V_ABSENT) &&
(r & (HPTE_R_KEY_HI | HPTE_R_KEY_LO)) ==
(HPTE_R_KEY_HI | HPTE_R_KEY_LO));
}
static void do_tlbies(struct kvm *kvm, unsigned long *rbvalues,
long npages, int global, bool need_sync)
{
long i;
/*
* We use the POWER9 5-operand versions of tlbie and tlbiel here.
* Since we are using RIC=0 PRS=0 R=0, and P7/P8 tlbiel ignores
* the RS field, this is backwards-compatible with P7 and P8.
*/
if (global) {
if (need_sync)
asm volatile("ptesync" : : : "memory");
for (i = 0; i < npages; ++i) {
asm volatile(PPC_TLBIE_5(%0,%1,0,0,0) : :
"r" (rbvalues[i]), "r" (kvm->arch.lpid));
}
if (cpu_has_feature(CPU_FTR_P9_TLBIE_BUG)) {
/*
* Need the extra ptesync to make sure we don't
* re-order the tlbie
*/
asm volatile("ptesync": : :"memory");
asm volatile(PPC_TLBIE_5(%0,%1,0,0,0) : :
"r" (rbvalues[0]), "r" (kvm->arch.lpid));
}
asm volatile("eieio; tlbsync; ptesync" : : : "memory");
} else {
if (need_sync)
asm volatile("ptesync" : : : "memory");
for (i = 0; i < npages; ++i) {
asm volatile(PPC_TLBIEL(%0,%1,0,0,0) : :
"r" (rbvalues[i]), "r" (0));
}
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, orig_pte, pte_r;
if (kvm_is_radix(kvm))
return H_FUNCTION;
if (pte_index >= kvmppc_hpt_npte(&kvm->arch.hpt))
return H_PARAMETER;
hpte = (__be64 *)(kvm->arch.hpt.virt + (pte_index << 4));
while (!try_lock_hpte(hpte, HPTE_V_HVLOCK))
cpu_relax();
pte = orig_pte = be64_to_cpu(hpte[0]);
pte_r = be64_to_cpu(hpte[1]);
if (cpu_has_feature(CPU_FTR_ARCH_300)) {
pte = hpte_new_to_old_v(pte, pte_r);
pte_r = hpte_new_to_old_r(pte_r);
}
if ((pte & (HPTE_V_ABSENT | HPTE_V_VALID)) == 0 ||
((flags & H_AVPN) && (pte & ~0x7fUL) != avpn) ||
((flags & H_ANDCOND) && (pte & avpn) != 0)) {
__unlock_hpte(hpte, orig_pte);
return H_NOT_FOUND;
}
rev = real_vmalloc_addr(&kvm->arch.hpt.rev[pte_index]);
v = pte & ~HPTE_V_HVLOCK;
if (v & HPTE_V_VALID) {
hpte[0] &= ~cpu_to_be64(HPTE_V_VALID);
rb = compute_tlbie_rb(v, pte_r, pte_index);
do_tlbies(kvm, &rb, 1, global_invalidates(kvm), true);
/*
* The reference (R) and change (C) bits in a HPT
* entry can be set by hardware at any time up until
* the HPTE is invalidated and the TLB invalidation
* sequence has completed. This means that when
* removing a HPTE, we need to re-read the HPTE after
* the invalidation sequence has completed in order to
* obtain reliable values of R and C.
*/
remove_revmap_chain(kvm, pte_index, rev, v,
be64_to_cpu(hpte[1]));
}
r = rev->guest_rpte & ~HPTE_GR_RESERVED;
note_hpte_modification(kvm, rev);
unlock_hpte(hpte, 0);
if (is_mmio_hpte(v, pte_r))
atomic64_inc(&kvm->arch.mmio_update);
if (v & HPTE_V_ABSENT)
v = (v & ~HPTE_V_ABSENT) | HPTE_V_VALID;
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.regs.gpr[4]);
}
long kvmppc_h_bulk_remove(struct kvm_vcpu *vcpu)
{
struct kvm *kvm = vcpu->kvm;
unsigned long *args = &vcpu->arch.regs.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, hp1;
if (kvm_is_radix(kvm))
return H_FUNCTION;
global = global_invalidates(kvm);
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 >= kvmppc_hpt_npte(&kvm->arch.hpt)) {
/* 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]);
hp1 = be64_to_cpu(hp[1]);
if (cpu_has_feature(CPU_FTR_ARCH_300)) {
hp0 = hpte_new_to_old_v(hp0, hp1);
hp1 = hpte_new_to_old_r(hp1);
}
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.hpt.rev[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;
if (is_mmio_hpte(hp0, hp1))
atomic64_inc(&kvm->arch.mmio_update);
continue;
}
/* leave it locked */
hp[0] &= ~cpu_to_be64(HPTE_V_VALID);
tlbrb[n] = compute_tlbie_rb(hp0, hp1, 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_v, pte_r;
if (kvm_is_radix(kvm))
return H_FUNCTION;
if (pte_index >= kvmppc_hpt_npte(&kvm->arch.hpt))
return H_PARAMETER;
hpte = (__be64 *)(kvm->arch.hpt.virt + (pte_index << 4));
while (!try_lock_hpte(hpte, HPTE_V_HVLOCK))
cpu_relax();
v = pte_v = be64_to_cpu(hpte[0]);
if (cpu_has_feature(CPU_FTR_ARCH_300))
v = hpte_new_to_old_v(v, be64_to_cpu(hpte[1]));
if ((v & (HPTE_V_ABSENT | HPTE_V_VALID)) == 0 ||
((flags & H_AVPN) && (v & ~0x7fUL) != avpn)) {
__unlock_hpte(hpte, pte_v);
return H_NOT_FOUND;
}
pte_r = be64_to_cpu(hpte[1]);
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.hpt.rev[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.
*/
r = (pte_r & ~mask) | bits;
if (hpte_is_writable(r) && !hpte_is_writable(pte_r))
r = hpte_make_readonly(r);
/* If the PTE is changing, invalidate it first */
if (r != pte_r) {
rb = compute_tlbie_rb(v, r, pte_index);
hpte[0] = cpu_to_be64((pte_v & ~HPTE_V_VALID) |
HPTE_V_ABSENT);
do_tlbies(kvm, &rb, 1, global_invalidates(kvm), true);
/* Don't lose R/C bit updates done by hardware */
r |= be64_to_cpu(hpte[1]) & (HPTE_R_R | HPTE_R_C);
hpte[1] = cpu_to_be64(r);
}
}
unlock_hpte(hpte, pte_v & ~HPTE_V_HVLOCK);
asm volatile("ptesync" : : : "memory");
if (is_mmio_hpte(v, pte_r))
atomic64_inc(&kvm->arch.mmio_update);
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 (kvm_is_radix(kvm))
return H_FUNCTION;
if (pte_index >= kvmppc_hpt_npte(&kvm->arch.hpt))
return H_PARAMETER;
if (flags & H_READ_4) {
pte_index &= ~3;
n = 4;
}
rev = real_vmalloc_addr(&kvm->arch.hpt.rev[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 (cpu_has_feature(CPU_FTR_ARCH_300)) {
v = hpte_new_to_old_v(v, r);
r = hpte_new_to_old_r(r);
}
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.regs.gpr[4 + i * 2] = v;
vcpu->arch.regs.gpr[5 + i * 2] = r;
}
return H_SUCCESS;
}
long kvmppc_h_clear_ref(struct kvm_vcpu *vcpu, unsigned long flags,
unsigned long pte_index)
{
struct kvm *kvm = vcpu->kvm;
__be64 *hpte;
unsigned long v, r, gr;
struct revmap_entry *rev;
unsigned long *rmap;
long ret = H_NOT_FOUND;
if (kvm_is_radix(kvm))
return H_FUNCTION;
if (pte_index >= kvmppc_hpt_npte(&kvm->arch.hpt))
return H_PARAMETER;
rev = real_vmalloc_addr(&kvm->arch.hpt.rev[pte_index]);
hpte = (__be64 *)(kvm->arch.hpt.virt + (pte_index << 4));
while (!try_lock_hpte(hpte, HPTE_V_HVLOCK))
cpu_relax();
v = be64_to_cpu(hpte[0]);
r = be64_to_cpu(hpte[1]);
if (!(v & (HPTE_V_VALID | HPTE_V_ABSENT)))
goto out;
gr = rev->guest_rpte;
if (rev->guest_rpte & HPTE_R_R) {
rev->guest_rpte &= ~HPTE_R_R;
note_hpte_modification(kvm, rev);
}
if (v & HPTE_V_VALID) {
gr |= r & (HPTE_R_R | HPTE_R_C);
if (r & HPTE_R_R) {
kvmppc_clear_ref_hpte(kvm, hpte, pte_index);
rmap = revmap_for_hpte(kvm, v, gr, NULL, NULL);
if (rmap) {
lock_rmap(rmap);
*rmap |= KVMPPC_RMAP_REFERENCED;
unlock_rmap(rmap);
}
}
}
vcpu->arch.regs.gpr[4] = gr;
ret = H_SUCCESS;
out:
unlock_hpte(hpte, v & ~HPTE_V_HVLOCK);
return ret;
}
long kvmppc_h_clear_mod(struct kvm_vcpu *vcpu, unsigned long flags,
unsigned long pte_index)
{
struct kvm *kvm = vcpu->kvm;
__be64 *hpte;
unsigned long v, r, gr;
struct revmap_entry *rev;
long ret = H_NOT_FOUND;
if (kvm_is_radix(kvm))
return H_FUNCTION;
if (pte_index >= kvmppc_hpt_npte(&kvm->arch.hpt))
return H_PARAMETER;
rev = real_vmalloc_addr(&kvm->arch.hpt.rev[pte_index]);
hpte = (__be64 *)(kvm->arch.hpt.virt + (pte_index << 4));
while (!try_lock_hpte(hpte, HPTE_V_HVLOCK))
cpu_relax();
v = be64_to_cpu(hpte[0]);
r = be64_to_cpu(hpte[1]);
if (!(v & (HPTE_V_VALID | HPTE_V_ABSENT)))
goto out;
gr = rev->guest_rpte;
if (gr & HPTE_R_C) {
rev->guest_rpte &= ~HPTE_R_C;
note_hpte_modification(kvm, rev);
}
if (v & HPTE_V_VALID) {
/* need to make it temporarily absent so C is stable */
hpte[0] |= cpu_to_be64(HPTE_V_ABSENT);
kvmppc_invalidate_hpte(kvm, hpte, pte_index);
r = be64_to_cpu(hpte[1]);
gr |= r & (HPTE_R_R | HPTE_R_C);
if (r & HPTE_R_C) {
hpte[1] = cpu_to_be64(r & ~HPTE_R_C);
eieio();
kvmppc_set_dirty_from_hpte(kvm, v, gr);
}
}
vcpu->arch.regs.gpr[4] = gr;
ret = H_SUCCESS;
out:
unlock_hpte(hpte, v & ~HPTE_V_HVLOCK);
return ret;
}
void kvmppc_invalidate_hpte(struct kvm *kvm, __be64 *hptep,
unsigned long pte_index)
{
unsigned long rb;
u64 hp0, hp1;
hptep[0] &= ~cpu_to_be64(HPTE_V_VALID);
hp0 = be64_to_cpu(hptep[0]);
hp1 = be64_to_cpu(hptep[1]);
if (cpu_has_feature(CPU_FTR_ARCH_300)) {
hp0 = hpte_new_to_old_v(hp0, hp1);
hp1 = hpte_new_to_old_r(hp1);
}
rb = compute_tlbie_rb(hp0, hp1, 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;
u64 hp0, hp1;
hp0 = be64_to_cpu(hptep[0]);
hp1 = be64_to_cpu(hptep[1]);
if (cpu_has_feature(CPU_FTR_ARCH_300)) {
hp0 = hpte_new_to_old_v(hp0, hp1);
hp1 = hpte_new_to_old_r(hp1);
}
rb = compute_tlbie_rb(hp0, hp1, 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 */
};
static struct mmio_hpte_cache_entry *mmio_cache_search(struct kvm_vcpu *vcpu,
unsigned long eaddr, unsigned long slb_v, long mmio_update)
{
struct mmio_hpte_cache_entry *entry = NULL;
unsigned int pshift;
unsigned int i;
for (i = 0; i < MMIO_HPTE_CACHE_SIZE; i++) {
entry = &vcpu->arch.mmio_cache.entry[i];
if (entry->mmio_update == mmio_update) {
pshift = entry->slb_base_pshift;
if ((entry->eaddr >> pshift) == (eaddr >> pshift) &&
entry->slb_v == slb_v)
return entry;
}
}
return NULL;
}
static struct mmio_hpte_cache_entry *
next_mmio_cache_entry(struct kvm_vcpu *vcpu)
{
unsigned int index = vcpu->arch.mmio_cache.index;
vcpu->arch.mmio_cache.index++;
if (vcpu->arch.mmio_cache.index == MMIO_HPTE_CACHE_SIZE)
vcpu->arch.mmio_cache.index = 0;
return &vcpu->arch.mmio_cache.entry[index];
}
/* 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, orig_v;
/* 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)) & kvmppc_hpt_mask(&kvm->arch.hpt);
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;
if (cpu_has_feature(CPU_FTR_ARCH_300))
v = hpte_new_to_old_v(v, be64_to_cpu(hpte[i+1]));
/* 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 = orig_v = be64_to_cpu(hpte[i]) & ~HPTE_V_HVLOCK;
r = be64_to_cpu(hpte[i+1]);
if (cpu_has_feature(CPU_FTR_ARCH_300)) {
v = hpte_new_to_old_v(v, r);
r = hpte_new_to_old_r(r);
}
/*
* Check the HPTE again, including base page size
*/
if ((v & valid) && (v & mask) == val &&
kvmppc_hpte_base_page_shift(v, r) == pshift)
/* Return with the HPTE still locked */
return (hash << 3) + (i >> 1);
__unlock_hpte(&hpte[i], orig_v);
}
if (val & HPTE_V_SECONDARY)
break;
val |= HPTE_V_SECONDARY;
hash = hash ^ kvmppc_hpt_mask(&kvm->arch.hpt);
}
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, orig_v;
__be64 *hpte;
unsigned long valid;
struct revmap_entry *rev;
unsigned long pp, key;
struct mmio_hpte_cache_entry *cache_entry = NULL;
long mmio_update = 0;
/* For protection fault, expect to find a valid HPTE */
valid = HPTE_V_VALID;
if (status & DSISR_NOHPTE) {
valid |= HPTE_V_ABSENT;
mmio_update = atomic64_read(&kvm->arch.mmio_update);
cache_entry = mmio_cache_search(vcpu, addr, slb_v, mmio_update);
}
if (cache_entry) {
index = cache_entry->pte_index;
v = cache_entry->hpte_v;
r = cache_entry->hpte_r;
gr = cache_entry->rpte;
} else {
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 = orig_v = be64_to_cpu(hpte[0]) & ~HPTE_V_HVLOCK;
r = be64_to_cpu(hpte[1]);
if (cpu_has_feature(CPU_FTR_ARCH_300)) {
v = hpte_new_to_old_v(v, r);
r = hpte_new_to_old_r(r);
}
rev = real_vmalloc_addr(&kvm->arch.hpt.rev[index]);
gr = rev->guest_rpte;
unlock_hpte(hpte, orig_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;
vcpu->arch.pgfault_cache = cache_entry;
/* Check the storage key to see if it is possibly emulated MMIO */
if ((r & (HPTE_R_KEY_HI | HPTE_R_KEY_LO)) ==
(HPTE_R_KEY_HI | HPTE_R_KEY_LO)) {
if (!cache_entry) {
unsigned int pshift = 12;
unsigned int pshift_index;
if (slb_v & SLB_VSID_L) {
pshift_index = ((slb_v & SLB_VSID_LP) >> 4);
pshift = slb_base_page_shift[pshift_index];
}
cache_entry = next_mmio_cache_entry(vcpu);
cache_entry->eaddr = addr;
cache_entry->slb_base_pshift = pshift;
cache_entry->pte_index = index;
cache_entry->hpte_v = v;
cache_entry->hpte_r = r;
cache_entry->rpte = gr;
cache_entry->slb_v = slb_v;
cache_entry->mmio_update = mmio_update;
}
if (data && (vcpu->arch.shregs.msr & MSR_IR))
return -2; /* MMIO emulation - load instr word */
}
return -1; /* send fault up to host kernel mode */
}