linux/arch/powerpc/kvm/book3s_32_mmu.c
Vipin K Parashar 4da934dc65 KVM: PPC: Book3S PR: Ratelimit copy data failure error messages
kvm_ppc_mmu_book3s_32/64 xlat() logs "KVM can't copy data" error
upon failing to copy user data to kernel space. This floods kernel
log once such fails occur in short time period. Ratelimit this
error to avoid flooding kernel logs upon copy data failures.

Signed-off-by: Vipin K Parashar <vipin@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2017-02-17 14:03:35 +11:00

432 lines
10 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 inline u32 sr_vsid(u32 sr_raw)
{
return sr_raw & 0x0fffffff;
}
static inline bool sr_valid(u32 sr_raw)
{
return (sr_raw & 0x80000000) ? false : true;
}
static inline bool sr_ks(u32 sr_raw)
{
return (sr_raw & 0x40000000) ? true: false;
}
static inline bool sr_kp(u32 sr_raw)
{
return (sr_raw & 0x20000000) ? true: false;
}
static int kvmppc_mmu_book3s_32_xlate_bat(struct kvm_vcpu *vcpu, gva_t eaddr,
struct kvmppc_pte *pte, bool data,
bool iswrite);
static int kvmppc_mmu_book3s_32_esid_to_vsid(struct kvm_vcpu *vcpu, ulong esid,
u64 *vsid);
static u32 find_sr(struct kvm_vcpu *vcpu, gva_t eaddr)
{
return kvmppc_get_sr(vcpu, (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, false))
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 kvm_vcpu *vcpu,
u32 sre, gva_t eaddr,
bool primary)
{
struct kvmppc_vcpu_book3s *vcpu_book3s = to_book3s(vcpu);
u32 page, hash, pteg, htabmask;
hva_t r;
page = (eaddr & 0x0FFFFFFF) >> 12;
htabmask = ((vcpu_book3s->sdr1 & 0x1FF) << 16) | 0xFFC0;
hash = ((sr_vsid(sre) ^ 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",
kvmppc_get_pc(vcpu), eaddr, vcpu_book3s->sdr1, pteg,
sr_vsid(sre));
r = gfn_to_hva(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(u32 sre, gva_t eaddr, bool primary)
{
return ((eaddr & 0x0fffffff) >> 22) | (sr_vsid(sre) << 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,
bool iswrite)
{
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 (kvmppc_get_msr(vcpu) & 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 (iswrite && !pte->may_write) {
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 iswrite, bool primary)
{
u32 sre;
hva_t ptegp;
u32 pteg[16];
u32 pte0, pte1;
u32 ptem = 0;
int i;
int found = 0;
sre = find_sr(vcpu, eaddr);
dprintk_pte("SR 0x%lx: vsid=0x%x, raw=0x%x\n", eaddr >> 28,
sr_vsid(sre), sre);
pte->vpage = kvmppc_mmu_book3s_32_ea_to_vp(vcpu, eaddr, data);
ptegp = kvmppc_mmu_book3s_32_get_pteg(vcpu, 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_ratelimited(KERN_ERR
"KVM: Can't copy data from 0x%lx!\n", ptegp);
goto no_page_found;
}
for (i=0; i<16; i+=2) {
pte0 = be32_to_cpu(pteg[i]);
pte1 = be32_to_cpu(pteg[i + 1]);
if (ptem == pte0) {
u8 pp;
pte->raddr = (pte1 & ~(0xFFFULL)) | (eaddr & 0xFFF);
pp = pte1 & 3;
if ((sr_kp(sre) && (kvmppc_get_msr(vcpu) & MSR_PR)) ||
(sr_ks(sre) && !(kvmppc_get_msr(vcpu) & 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;
}
dprintk_pte("MMU: Found PTE -> %x %x - %x\n",
pte0, pte1, pp);
found = 1;
break;
}
}
/* Update PTE C and A bits, so the guest's swapper knows we used the
page */
if (found) {
u32 pte_r = pte1;
char __user *addr = (char __user *) (ptegp + (i+1) * sizeof(u32));
/*
* Use single-byte writes to update the HPTE, to
* conform to what real hardware does.
*/
if (pte->may_read && !(pte_r & PTEG_FLAG_ACCESSED)) {
pte_r |= PTEG_FLAG_ACCESSED;
put_user(pte_r >> 8, addr + 2);
}
if (iswrite && pte->may_write && !(pte_r & PTEG_FLAG_DIRTY)) {
pte_r |= PTEG_FLAG_DIRTY;
put_user(pte_r, addr + 3);
}
if (!pte->may_read || (iswrite && !pte->may_write))
return -EPERM;
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%x)\n",
i, be32_to_cpu(pteg[i]),
be32_to_cpu(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,
bool iswrite)
{
int r;
ulong mp_ea = vcpu->arch.magic_page_ea;
pte->eaddr = eaddr;
pte->page_size = MMU_PAGE_4K;
/* Magic page override */
if (unlikely(mp_ea) &&
unlikely((eaddr & ~0xfffULL) == (mp_ea & ~0xfffULL)) &&
!(kvmppc_get_msr(vcpu) & MSR_PR)) {
pte->vpage = kvmppc_mmu_book3s_32_ea_to_vp(vcpu, eaddr, data);
pte->raddr = vcpu->arch.magic_page_pa | (pte->raddr & 0xfff);
pte->raddr &= KVM_PAM;
pte->may_execute = true;
pte->may_read = true;
pte->may_write = true;
return 0;
}
r = kvmppc_mmu_book3s_32_xlate_bat(vcpu, eaddr, pte, data, iswrite);
if (r < 0)
r = kvmppc_mmu_book3s_32_xlate_pte(vcpu, eaddr, pte,
data, iswrite, true);
if (r == -ENOENT)
r = kvmppc_mmu_book3s_32_xlate_pte(vcpu, eaddr, pte,
data, iswrite, false);
return r;
}
static u32 kvmppc_mmu_book3s_32_mfsrin(struct kvm_vcpu *vcpu, u32 srnum)
{
return kvmppc_get_sr(vcpu, srnum);
}
static void kvmppc_mmu_book3s_32_mtsrin(struct kvm_vcpu *vcpu, u32 srnum,
ulong value)
{
kvmppc_set_sr(vcpu, srnum, value);
kvmppc_mmu_map_segment(vcpu, srnum << SID_SHIFT);
}
static void kvmppc_mmu_book3s_32_tlbie(struct kvm_vcpu *vcpu, ulong ea, bool large)
{
int i;
struct kvm_vcpu *v;
/* flush this VA on all cpus */
kvm_for_each_vcpu(i, v, vcpu->kvm)
kvmppc_mmu_pte_flush(v, ea, 0x0FFFF000);
}
static int kvmppc_mmu_book3s_32_esid_to_vsid(struct kvm_vcpu *vcpu, ulong esid,
u64 *vsid)
{
ulong ea = esid << SID_SHIFT;
u32 sr;
u64 gvsid = esid;
u64 msr = kvmppc_get_msr(vcpu);
if (msr & (MSR_DR|MSR_IR)) {
sr = find_sr(vcpu, ea);
if (sr_valid(sr))
gvsid = sr_vsid(sr);
}
/* 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 (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(sr))
*vsid = sr_vsid(sr);
else
*vsid = VSID_BAT | gvsid;
break;
default:
BUG();
}
if (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;
}