linux/arch/powerpc/kvm/powerpc.c
Hollis Blanchard 83aae4a809 KVM: ppc: Write only modified shadow entries into the TLB on exit
Track which TLB entries need to be written, instead of overwriting everything
below the high water mark. Typically only a single guest TLB entry will be
modified in a single exit.

Guest boot time performance improvement: about 15%.

Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-10-15 10:15:16 +02:00

551 lines
12 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 IBM Corp. 2007
*
* Authors: Hollis Blanchard <hollisb@us.ibm.com>
* Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>
*/
#include <linux/errno.h>
#include <linux/err.h>
#include <linux/kvm_host.h>
#include <linux/module.h>
#include <linux/vmalloc.h>
#include <linux/fs.h>
#include <asm/cputable.h>
#include <asm/uaccess.h>
#include <asm/kvm_ppc.h>
#include <asm/tlbflush.h>
gfn_t unalias_gfn(struct kvm *kvm, gfn_t gfn)
{
return gfn;
}
int kvm_cpu_has_interrupt(struct kvm_vcpu *v)
{
return !!(v->arch.pending_exceptions);
}
int kvm_arch_vcpu_runnable(struct kvm_vcpu *v)
{
return !(v->arch.msr & MSR_WE);
}
int kvmppc_emulate_mmio(struct kvm_run *run, struct kvm_vcpu *vcpu)
{
enum emulation_result er;
int r;
er = kvmppc_emulate_instruction(run, vcpu);
switch (er) {
case EMULATE_DONE:
/* Future optimization: only reload non-volatiles if they were
* actually modified. */
r = RESUME_GUEST_NV;
break;
case EMULATE_DO_MMIO:
run->exit_reason = KVM_EXIT_MMIO;
/* We must reload nonvolatiles because "update" load/store
* instructions modify register state. */
/* Future optimization: only reload non-volatiles if they were
* actually modified. */
r = RESUME_HOST_NV;
break;
case EMULATE_FAIL:
/* XXX Deliver Program interrupt to guest. */
printk(KERN_EMERG "%s: emulation failed (%08x)\n", __func__,
vcpu->arch.last_inst);
r = RESUME_HOST;
break;
default:
BUG();
}
return r;
}
void kvm_arch_hardware_enable(void *garbage)
{
}
void kvm_arch_hardware_disable(void *garbage)
{
}
int kvm_arch_hardware_setup(void)
{
return 0;
}
void kvm_arch_hardware_unsetup(void)
{
}
void kvm_arch_check_processor_compat(void *rtn)
{
int r;
if (strcmp(cur_cpu_spec->platform, "ppc440") == 0)
r = 0;
else
r = -ENOTSUPP;
*(int *)rtn = r;
}
struct kvm *kvm_arch_create_vm(void)
{
struct kvm *kvm;
kvm = kzalloc(sizeof(struct kvm), GFP_KERNEL);
if (!kvm)
return ERR_PTR(-ENOMEM);
return kvm;
}
static void kvmppc_free_vcpus(struct kvm *kvm)
{
unsigned int i;
for (i = 0; i < KVM_MAX_VCPUS; ++i) {
if (kvm->vcpus[i]) {
kvm_arch_vcpu_free(kvm->vcpus[i]);
kvm->vcpus[i] = NULL;
}
}
}
void kvm_arch_destroy_vm(struct kvm *kvm)
{
kvmppc_free_vcpus(kvm);
kvm_free_physmem(kvm);
kfree(kvm);
}
int kvm_dev_ioctl_check_extension(long ext)
{
int r;
switch (ext) {
case KVM_CAP_USER_MEMORY:
r = 1;
break;
case KVM_CAP_COALESCED_MMIO:
r = KVM_COALESCED_MMIO_PAGE_OFFSET;
break;
default:
r = 0;
break;
}
return r;
}
long kvm_arch_dev_ioctl(struct file *filp,
unsigned int ioctl, unsigned long arg)
{
return -EINVAL;
}
int kvm_arch_set_memory_region(struct kvm *kvm,
struct kvm_userspace_memory_region *mem,
struct kvm_memory_slot old,
int user_alloc)
{
return 0;
}
void kvm_arch_flush_shadow(struct kvm *kvm)
{
}
struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm, unsigned int id)
{
struct kvm_vcpu *vcpu;
int err;
vcpu = kmem_cache_zalloc(kvm_vcpu_cache, GFP_KERNEL);
if (!vcpu) {
err = -ENOMEM;
goto out;
}
err = kvm_vcpu_init(vcpu, kvm, id);
if (err)
goto free_vcpu;
return vcpu;
free_vcpu:
kmem_cache_free(kvm_vcpu_cache, vcpu);
out:
return ERR_PTR(err);
}
void kvm_arch_vcpu_free(struct kvm_vcpu *vcpu)
{
kvm_vcpu_uninit(vcpu);
kmem_cache_free(kvm_vcpu_cache, vcpu);
}
void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
{
kvm_arch_vcpu_free(vcpu);
}
int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
{
unsigned int priority = exception_priority[BOOKE_INTERRUPT_DECREMENTER];
return test_bit(priority, &vcpu->arch.pending_exceptions);
}
static void kvmppc_decrementer_func(unsigned long data)
{
struct kvm_vcpu *vcpu = (struct kvm_vcpu *)data;
kvmppc_queue_exception(vcpu, BOOKE_INTERRUPT_DECREMENTER);
if (waitqueue_active(&vcpu->wq)) {
wake_up_interruptible(&vcpu->wq);
vcpu->stat.halt_wakeup++;
}
}
int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu)
{
setup_timer(&vcpu->arch.dec_timer, kvmppc_decrementer_func,
(unsigned long)vcpu);
return 0;
}
void kvm_arch_vcpu_uninit(struct kvm_vcpu *vcpu)
{
}
/* Note: clearing MSR[DE] just means that the debug interrupt will not be
* delivered *immediately*. Instead, it simply sets the appropriate DBSR bits.
* If those DBSR bits are still set when MSR[DE] is re-enabled, the interrupt
* will be delivered as an "imprecise debug event" (which is indicated by
* DBSR[IDE].
*/
static void kvmppc_disable_debug_interrupts(void)
{
mtmsr(mfmsr() & ~MSR_DE);
}
static void kvmppc_restore_host_debug_state(struct kvm_vcpu *vcpu)
{
kvmppc_disable_debug_interrupts();
mtspr(SPRN_IAC1, vcpu->arch.host_iac[0]);
mtspr(SPRN_IAC2, vcpu->arch.host_iac[1]);
mtspr(SPRN_IAC3, vcpu->arch.host_iac[2]);
mtspr(SPRN_IAC4, vcpu->arch.host_iac[3]);
mtspr(SPRN_DBCR1, vcpu->arch.host_dbcr1);
mtspr(SPRN_DBCR2, vcpu->arch.host_dbcr2);
mtspr(SPRN_DBCR0, vcpu->arch.host_dbcr0);
mtmsr(vcpu->arch.host_msr);
}
static void kvmppc_load_guest_debug_registers(struct kvm_vcpu *vcpu)
{
struct kvm_guest_debug *dbg = &vcpu->guest_debug;
u32 dbcr0 = 0;
vcpu->arch.host_msr = mfmsr();
kvmppc_disable_debug_interrupts();
/* Save host debug register state. */
vcpu->arch.host_iac[0] = mfspr(SPRN_IAC1);
vcpu->arch.host_iac[1] = mfspr(SPRN_IAC2);
vcpu->arch.host_iac[2] = mfspr(SPRN_IAC3);
vcpu->arch.host_iac[3] = mfspr(SPRN_IAC4);
vcpu->arch.host_dbcr0 = mfspr(SPRN_DBCR0);
vcpu->arch.host_dbcr1 = mfspr(SPRN_DBCR1);
vcpu->arch.host_dbcr2 = mfspr(SPRN_DBCR2);
/* set registers up for guest */
if (dbg->bp[0]) {
mtspr(SPRN_IAC1, dbg->bp[0]);
dbcr0 |= DBCR0_IAC1 | DBCR0_IDM;
}
if (dbg->bp[1]) {
mtspr(SPRN_IAC2, dbg->bp[1]);
dbcr0 |= DBCR0_IAC2 | DBCR0_IDM;
}
if (dbg->bp[2]) {
mtspr(SPRN_IAC3, dbg->bp[2]);
dbcr0 |= DBCR0_IAC3 | DBCR0_IDM;
}
if (dbg->bp[3]) {
mtspr(SPRN_IAC4, dbg->bp[3]);
dbcr0 |= DBCR0_IAC4 | DBCR0_IDM;
}
mtspr(SPRN_DBCR0, dbcr0);
mtspr(SPRN_DBCR1, 0);
mtspr(SPRN_DBCR2, 0);
}
void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
{
int i;
if (vcpu->guest_debug.enabled)
kvmppc_load_guest_debug_registers(vcpu);
/* Mark every guest entry in the shadow TLB entry modified, so that they
* will all be reloaded on the next vcpu run (instead of being
* demand-faulted). */
for (i = 0; i <= tlb_44x_hwater; i++)
kvmppc_tlbe_set_modified(vcpu, i);
}
void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
{
if (vcpu->guest_debug.enabled)
kvmppc_restore_host_debug_state(vcpu);
/* Don't leave guest TLB entries resident when being de-scheduled. */
/* XXX It would be nice to differentiate between heavyweight exit and
* sched_out here, since we could avoid the TLB flush for heavyweight
* exits. */
_tlbia();
}
int kvm_arch_vcpu_ioctl_debug_guest(struct kvm_vcpu *vcpu,
struct kvm_debug_guest *dbg)
{
int i;
vcpu->guest_debug.enabled = dbg->enabled;
if (vcpu->guest_debug.enabled) {
for (i=0; i < ARRAY_SIZE(vcpu->guest_debug.bp); i++) {
if (dbg->breakpoints[i].enabled)
vcpu->guest_debug.bp[i] = dbg->breakpoints[i].address;
else
vcpu->guest_debug.bp[i] = 0;
}
}
return 0;
}
static void kvmppc_complete_dcr_load(struct kvm_vcpu *vcpu,
struct kvm_run *run)
{
u32 *gpr = &vcpu->arch.gpr[vcpu->arch.io_gpr];
*gpr = run->dcr.data;
}
static void kvmppc_complete_mmio_load(struct kvm_vcpu *vcpu,
struct kvm_run *run)
{
u32 *gpr = &vcpu->arch.gpr[vcpu->arch.io_gpr];
if (run->mmio.len > sizeof(*gpr)) {
printk(KERN_ERR "bad MMIO length: %d\n", run->mmio.len);
return;
}
if (vcpu->arch.mmio_is_bigendian) {
switch (run->mmio.len) {
case 4: *gpr = *(u32 *)run->mmio.data; break;
case 2: *gpr = *(u16 *)run->mmio.data; break;
case 1: *gpr = *(u8 *)run->mmio.data; break;
}
} else {
/* Convert BE data from userland back to LE. */
switch (run->mmio.len) {
case 4: *gpr = ld_le32((u32 *)run->mmio.data); break;
case 2: *gpr = ld_le16((u16 *)run->mmio.data); break;
case 1: *gpr = *(u8 *)run->mmio.data; break;
}
}
}
int kvmppc_handle_load(struct kvm_run *run, struct kvm_vcpu *vcpu,
unsigned int rt, unsigned int bytes, int is_bigendian)
{
if (bytes > sizeof(run->mmio.data)) {
printk(KERN_ERR "%s: bad MMIO length: %d\n", __func__,
run->mmio.len);
}
run->mmio.phys_addr = vcpu->arch.paddr_accessed;
run->mmio.len = bytes;
run->mmio.is_write = 0;
vcpu->arch.io_gpr = rt;
vcpu->arch.mmio_is_bigendian = is_bigendian;
vcpu->mmio_needed = 1;
vcpu->mmio_is_write = 0;
return EMULATE_DO_MMIO;
}
int kvmppc_handle_store(struct kvm_run *run, struct kvm_vcpu *vcpu,
u32 val, unsigned int bytes, int is_bigendian)
{
void *data = run->mmio.data;
if (bytes > sizeof(run->mmio.data)) {
printk(KERN_ERR "%s: bad MMIO length: %d\n", __func__,
run->mmio.len);
}
run->mmio.phys_addr = vcpu->arch.paddr_accessed;
run->mmio.len = bytes;
run->mmio.is_write = 1;
vcpu->mmio_needed = 1;
vcpu->mmio_is_write = 1;
/* Store the value at the lowest bytes in 'data'. */
if (is_bigendian) {
switch (bytes) {
case 4: *(u32 *)data = val; break;
case 2: *(u16 *)data = val; break;
case 1: *(u8 *)data = val; break;
}
} else {
/* Store LE value into 'data'. */
switch (bytes) {
case 4: st_le32(data, val); break;
case 2: st_le16(data, val); break;
case 1: *(u8 *)data = val; break;
}
}
return EMULATE_DO_MMIO;
}
int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
{
int r;
sigset_t sigsaved;
vcpu_load(vcpu);
if (vcpu->sigset_active)
sigprocmask(SIG_SETMASK, &vcpu->sigset, &sigsaved);
if (vcpu->mmio_needed) {
if (!vcpu->mmio_is_write)
kvmppc_complete_mmio_load(vcpu, run);
vcpu->mmio_needed = 0;
} else if (vcpu->arch.dcr_needed) {
if (!vcpu->arch.dcr_is_write)
kvmppc_complete_dcr_load(vcpu, run);
vcpu->arch.dcr_needed = 0;
}
kvmppc_check_and_deliver_interrupts(vcpu);
local_irq_disable();
kvm_guest_enter();
r = __kvmppc_vcpu_run(run, vcpu);
kvm_guest_exit();
local_irq_enable();
if (vcpu->sigset_active)
sigprocmask(SIG_SETMASK, &sigsaved, NULL);
vcpu_put(vcpu);
return r;
}
int kvm_vcpu_ioctl_interrupt(struct kvm_vcpu *vcpu, struct kvm_interrupt *irq)
{
kvmppc_queue_exception(vcpu, BOOKE_INTERRUPT_EXTERNAL);
if (waitqueue_active(&vcpu->wq)) {
wake_up_interruptible(&vcpu->wq);
vcpu->stat.halt_wakeup++;
}
return 0;
}
int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
struct kvm_mp_state *mp_state)
{
return -EINVAL;
}
int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
struct kvm_mp_state *mp_state)
{
return -EINVAL;
}
long kvm_arch_vcpu_ioctl(struct file *filp,
unsigned int ioctl, unsigned long arg)
{
struct kvm_vcpu *vcpu = filp->private_data;
void __user *argp = (void __user *)arg;
long r;
switch (ioctl) {
case KVM_INTERRUPT: {
struct kvm_interrupt irq;
r = -EFAULT;
if (copy_from_user(&irq, argp, sizeof(irq)))
goto out;
r = kvm_vcpu_ioctl_interrupt(vcpu, &irq);
break;
}
default:
r = -EINVAL;
}
out:
return r;
}
int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm, struct kvm_dirty_log *log)
{
return -ENOTSUPP;
}
long kvm_arch_vm_ioctl(struct file *filp,
unsigned int ioctl, unsigned long arg)
{
long r;
switch (ioctl) {
default:
r = -EINVAL;
}
return r;
}
int kvm_arch_init(void *opaque)
{
return 0;
}
void kvm_arch_exit(void)
{
}