kernel-fxtec-pro1x/arch/powerpc/kvm/book3s_32_mmu.c
Alexander Graf 666e7252a1 KVM: PPC: Convert MSR to shared page
One of the most obvious registers to share with the guest directly is the
MSR. The MSR contains the "interrupts enabled" flag which the guest has to
toggle in critical sections.

So in order to bring the overhead of interrupt en- and disabling down, let's
put msr into the shared page. Keep in mind that even though you can fully read
its contents, writing to it doesn't always update all state. There are a few
safe fields that don't require hypervisor interaction. See the documentation
for a list of MSR bits that are safe to be set from inside the guest.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-10-24 10:50:43 +02:00

396 lines
9.4 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.
*
* 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 SUSE Linux Products GmbH 2009
*
* Authors: Alexander Graf <agraf@suse.de>
*/
#include <linux/types.h>
#include <linux/string.h>
#include <linux/kvm.h>
#include <linux/kvm_host.h>
#include <linux/highmem.h>
#include <asm/tlbflush.h>
#include <asm/kvm_ppc.h>
#include <asm/kvm_book3s.h>
/* #define DEBUG_MMU */
/* #define DEBUG_MMU_PTE */
/* #define DEBUG_MMU_PTE_IP 0xfff14c40 */
#ifdef DEBUG_MMU
#define dprintk(X...) printk(KERN_INFO X)
#else
#define dprintk(X...) do { } while(0)
#endif
#ifdef DEBUG_MMU_PTE
#define dprintk_pte(X...) printk(KERN_INFO X)
#else
#define dprintk_pte(X...) do { } while(0)
#endif
#define PTEG_FLAG_ACCESSED 0x00000100
#define PTEG_FLAG_DIRTY 0x00000080
#ifndef SID_SHIFT
#define SID_SHIFT 28
#endif
static inline bool check_debug_ip(struct kvm_vcpu *vcpu)
{
#ifdef DEBUG_MMU_PTE_IP
return vcpu->arch.pc == DEBUG_MMU_PTE_IP;
#else
return true;
#endif
}
static int kvmppc_mmu_book3s_32_xlate_bat(struct kvm_vcpu *vcpu, gva_t eaddr,
struct kvmppc_pte *pte, bool data);
static int kvmppc_mmu_book3s_32_esid_to_vsid(struct kvm_vcpu *vcpu, ulong esid,
u64 *vsid);
static struct kvmppc_sr *find_sr(struct kvmppc_vcpu_book3s *vcpu_book3s, gva_t eaddr)
{
return &vcpu_book3s->sr[(eaddr >> 28) & 0xf];
}
static u64 kvmppc_mmu_book3s_32_ea_to_vp(struct kvm_vcpu *vcpu, gva_t eaddr,
bool data)
{
u64 vsid;
struct kvmppc_pte pte;
if (!kvmppc_mmu_book3s_32_xlate_bat(vcpu, eaddr, &pte, data))
return pte.vpage;
kvmppc_mmu_book3s_32_esid_to_vsid(vcpu, eaddr >> SID_SHIFT, &vsid);
return (((u64)eaddr >> 12) & 0xffff) | (vsid << 16);
}
static void kvmppc_mmu_book3s_32_reset_msr(struct kvm_vcpu *vcpu)
{
kvmppc_set_msr(vcpu, 0);
}
static hva_t kvmppc_mmu_book3s_32_get_pteg(struct kvmppc_vcpu_book3s *vcpu_book3s,
struct kvmppc_sr *sre, gva_t eaddr,
bool primary)
{
u32 page, hash, pteg, htabmask;
hva_t r;
page = (eaddr & 0x0FFFFFFF) >> 12;
htabmask = ((vcpu_book3s->sdr1 & 0x1FF) << 16) | 0xFFC0;
hash = ((sre->vsid ^ page) << 6);
if (!primary)
hash = ~hash;
hash &= htabmask;
pteg = (vcpu_book3s->sdr1 & 0xffff0000) | hash;
dprintk("MMU: pc=0x%lx eaddr=0x%lx sdr1=0x%llx pteg=0x%x vsid=0x%x\n",
vcpu_book3s->vcpu.arch.pc, eaddr, vcpu_book3s->sdr1, pteg,
sre->vsid);
r = gfn_to_hva(vcpu_book3s->vcpu.kvm, pteg >> PAGE_SHIFT);
if (kvm_is_error_hva(r))
return r;
return r | (pteg & ~PAGE_MASK);
}
static u32 kvmppc_mmu_book3s_32_get_ptem(struct kvmppc_sr *sre, gva_t eaddr,
bool primary)
{
return ((eaddr & 0x0fffffff) >> 22) | (sre->vsid << 7) |
(primary ? 0 : 0x40) | 0x80000000;
}
static int kvmppc_mmu_book3s_32_xlate_bat(struct kvm_vcpu *vcpu, gva_t eaddr,
struct kvmppc_pte *pte, bool data)
{
struct kvmppc_vcpu_book3s *vcpu_book3s = to_book3s(vcpu);
struct kvmppc_bat *bat;
int i;
for (i = 0; i < 8; i++) {
if (data)
bat = &vcpu_book3s->dbat[i];
else
bat = &vcpu_book3s->ibat[i];
if (vcpu->arch.shared->msr & MSR_PR) {
if (!bat->vp)
continue;
} else {
if (!bat->vs)
continue;
}
if (check_debug_ip(vcpu))
{
dprintk_pte("%cBAT %02d: 0x%lx - 0x%x (0x%x)\n",
data ? 'd' : 'i', i, eaddr, bat->bepi,
bat->bepi_mask);
}
if ((eaddr & bat->bepi_mask) == bat->bepi) {
u64 vsid;
kvmppc_mmu_book3s_32_esid_to_vsid(vcpu,
eaddr >> SID_SHIFT, &vsid);
vsid <<= 16;
pte->vpage = (((u64)eaddr >> 12) & 0xffff) | vsid;
pte->raddr = bat->brpn | (eaddr & ~bat->bepi_mask);
pte->may_read = bat->pp;
pte->may_write = bat->pp > 1;
pte->may_execute = true;
if (!pte->may_read) {
printk(KERN_INFO "BAT is not readable!\n");
continue;
}
if (!pte->may_write) {
/* let's treat r/o BATs as not-readable for now */
dprintk_pte("BAT is read-only!\n");
continue;
}
return 0;
}
}
return -ENOENT;
}
static int kvmppc_mmu_book3s_32_xlate_pte(struct kvm_vcpu *vcpu, gva_t eaddr,
struct kvmppc_pte *pte, bool data,
bool primary)
{
struct kvmppc_vcpu_book3s *vcpu_book3s = to_book3s(vcpu);
struct kvmppc_sr *sre;
hva_t ptegp;
u32 pteg[16];
u32 ptem = 0;
int i;
int found = 0;
sre = find_sr(vcpu_book3s, eaddr);
dprintk_pte("SR 0x%lx: vsid=0x%x, raw=0x%x\n", eaddr >> 28,
sre->vsid, sre->raw);
pte->vpage = kvmppc_mmu_book3s_32_ea_to_vp(vcpu, eaddr, data);
ptegp = kvmppc_mmu_book3s_32_get_pteg(vcpu_book3s, sre, eaddr, primary);
if (kvm_is_error_hva(ptegp)) {
printk(KERN_INFO "KVM: Invalid PTEG!\n");
goto no_page_found;
}
ptem = kvmppc_mmu_book3s_32_get_ptem(sre, eaddr, primary);
if(copy_from_user(pteg, (void __user *)ptegp, sizeof(pteg))) {
printk(KERN_ERR "KVM: Can't copy data from 0x%lx!\n", ptegp);
goto no_page_found;
}
for (i=0; i<16; i+=2) {
if (ptem == pteg[i]) {
u8 pp;
pte->raddr = (pteg[i+1] & ~(0xFFFULL)) | (eaddr & 0xFFF);
pp = pteg[i+1] & 3;
if ((sre->Kp && (vcpu->arch.shared->msr & MSR_PR)) ||
(sre->Ks && !(vcpu->arch.shared->msr & MSR_PR)))
pp |= 4;
pte->may_write = false;
pte->may_read = false;
pte->may_execute = true;
switch (pp) {
case 0:
case 1:
case 2:
case 6:
pte->may_write = true;
case 3:
case 5:
case 7:
pte->may_read = true;
break;
}
if ( !pte->may_read )
continue;
dprintk_pte("MMU: Found PTE -> %x %x - %x\n",
pteg[i], pteg[i+1], pp);
found = 1;
break;
}
}
/* Update PTE C and A bits, so the guest's swapper knows we used the
page */
if (found) {
u32 oldpte = pteg[i+1];
if (pte->may_read)
pteg[i+1] |= PTEG_FLAG_ACCESSED;
if (pte->may_write)
pteg[i+1] |= PTEG_FLAG_DIRTY;
else
dprintk_pte("KVM: Mapping read-only page!\n");
/* Write back into the PTEG */
if (pteg[i+1] != oldpte)
copy_to_user((void __user *)ptegp, pteg, sizeof(pteg));
return 0;
}
no_page_found:
if (check_debug_ip(vcpu)) {
dprintk_pte("KVM MMU: No PTE found (sdr1=0x%llx ptegp=0x%lx)\n",
to_book3s(vcpu)->sdr1, ptegp);
for (i=0; i<16; i+=2) {
dprintk_pte(" %02d: 0x%x - 0x%x (0x%llx)\n",
i, pteg[i], pteg[i+1], ptem);
}
}
return -ENOENT;
}
static int kvmppc_mmu_book3s_32_xlate(struct kvm_vcpu *vcpu, gva_t eaddr,
struct kvmppc_pte *pte, bool data)
{
int r;
pte->eaddr = eaddr;
r = kvmppc_mmu_book3s_32_xlate_bat(vcpu, eaddr, pte, data);
if (r < 0)
r = kvmppc_mmu_book3s_32_xlate_pte(vcpu, eaddr, pte, data, true);
if (r < 0)
r = kvmppc_mmu_book3s_32_xlate_pte(vcpu, eaddr, pte, data, false);
return r;
}
static u32 kvmppc_mmu_book3s_32_mfsrin(struct kvm_vcpu *vcpu, u32 srnum)
{
return to_book3s(vcpu)->sr[srnum].raw;
}
static void kvmppc_mmu_book3s_32_mtsrin(struct kvm_vcpu *vcpu, u32 srnum,
ulong value)
{
struct kvmppc_sr *sre;
sre = &to_book3s(vcpu)->sr[srnum];
/* Flush any left-over shadows from the previous SR */
/* XXX Not necessary? */
/* kvmppc_mmu_pte_flush(vcpu, ((u64)sre->vsid) << 28, 0xf0000000ULL); */
/* And then put in the new SR */
sre->raw = value;
sre->vsid = (value & 0x0fffffff);
sre->valid = (value & 0x80000000) ? false : true;
sre->Ks = (value & 0x40000000) ? true : false;
sre->Kp = (value & 0x20000000) ? true : false;
sre->nx = (value & 0x10000000) ? true : false;
/* Map the new segment */
kvmppc_mmu_map_segment(vcpu, srnum << SID_SHIFT);
}
static void kvmppc_mmu_book3s_32_tlbie(struct kvm_vcpu *vcpu, ulong ea, bool large)
{
kvmppc_mmu_pte_flush(vcpu, ea, 0x0FFFF000);
}
static int kvmppc_mmu_book3s_32_esid_to_vsid(struct kvm_vcpu *vcpu, ulong esid,
u64 *vsid)
{
ulong ea = esid << SID_SHIFT;
struct kvmppc_sr *sr;
u64 gvsid = esid;
if (vcpu->arch.shared->msr & (MSR_DR|MSR_IR)) {
sr = find_sr(to_book3s(vcpu), ea);
if (sr->valid)
gvsid = sr->vsid;
}
/* In case we only have one of MSR_IR or MSR_DR set, let's put
that in the real-mode context (and hope RM doesn't access
high memory) */
switch (vcpu->arch.shared->msr & (MSR_DR|MSR_IR)) {
case 0:
*vsid = VSID_REAL | esid;
break;
case MSR_IR:
*vsid = VSID_REAL_IR | gvsid;
break;
case MSR_DR:
*vsid = VSID_REAL_DR | gvsid;
break;
case MSR_DR|MSR_IR:
if (sr->valid)
*vsid = sr->vsid;
else
*vsid = VSID_BAT | gvsid;
break;
default:
BUG();
}
if (vcpu->arch.shared->msr & MSR_PR)
*vsid |= VSID_PR;
return 0;
}
static bool kvmppc_mmu_book3s_32_is_dcbz32(struct kvm_vcpu *vcpu)
{
return true;
}
void kvmppc_mmu_book3s_32_init(struct kvm_vcpu *vcpu)
{
struct kvmppc_mmu *mmu = &vcpu->arch.mmu;
mmu->mtsrin = kvmppc_mmu_book3s_32_mtsrin;
mmu->mfsrin = kvmppc_mmu_book3s_32_mfsrin;
mmu->xlate = kvmppc_mmu_book3s_32_xlate;
mmu->reset_msr = kvmppc_mmu_book3s_32_reset_msr;
mmu->tlbie = kvmppc_mmu_book3s_32_tlbie;
mmu->esid_to_vsid = kvmppc_mmu_book3s_32_esid_to_vsid;
mmu->ea_to_vp = kvmppc_mmu_book3s_32_ea_to_vp;
mmu->is_dcbz32 = kvmppc_mmu_book3s_32_is_dcbz32;
mmu->slbmte = NULL;
mmu->slbmfee = NULL;
mmu->slbmfev = NULL;
mmu->slbie = NULL;
mmu->slbia = NULL;
}