linux/arch/powerpc/kvm/44x.c
Alexander Graf 96bc451a15 KVM: PPC: Introduce shared page
For transparent variable sharing between the hypervisor and guest, I introduce
a shared page. This shared page will contain all the registers the guest can
read and write safely without exiting guest context.

This patch only implements the stubs required for the basic structure of the
shared page. The actual register moving follows.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-10-24 10:50:42 +02:00

167 lines
3.8 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. 2008
*
* Authors: Hollis Blanchard <hollisb@us.ibm.com>
*/
#include <linux/kvm_host.h>
#include <linux/slab.h>
#include <linux/err.h>
#include <asm/reg.h>
#include <asm/cputable.h>
#include <asm/tlbflush.h>
#include <asm/kvm_44x.h>
#include <asm/kvm_ppc.h>
#include "44x_tlb.h"
void kvmppc_core_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
{
kvmppc_44x_tlb_load(vcpu);
}
void kvmppc_core_vcpu_put(struct kvm_vcpu *vcpu)
{
kvmppc_44x_tlb_put(vcpu);
}
int kvmppc_core_check_processor_compat(void)
{
int r;
if (strcmp(cur_cpu_spec->platform, "ppc440") == 0)
r = 0;
else
r = -ENOTSUPP;
return r;
}
int kvmppc_core_vcpu_setup(struct kvm_vcpu *vcpu)
{
struct kvmppc_vcpu_44x *vcpu_44x = to_44x(vcpu);
struct kvmppc_44x_tlbe *tlbe = &vcpu_44x->guest_tlb[0];
int i;
tlbe->tid = 0;
tlbe->word0 = PPC44x_TLB_16M | PPC44x_TLB_VALID;
tlbe->word1 = 0;
tlbe->word2 = PPC44x_TLB_SX | PPC44x_TLB_SW | PPC44x_TLB_SR;
tlbe++;
tlbe->tid = 0;
tlbe->word0 = 0xef600000 | PPC44x_TLB_4K | PPC44x_TLB_VALID;
tlbe->word1 = 0xef600000;
tlbe->word2 = PPC44x_TLB_SX | PPC44x_TLB_SW | PPC44x_TLB_SR
| PPC44x_TLB_I | PPC44x_TLB_G;
/* Since the guest can directly access the timebase, it must know the
* real timebase frequency. Accordingly, it must see the state of
* CCR1[TCS]. */
vcpu->arch.ccr1 = mfspr(SPRN_CCR1);
for (i = 0; i < ARRAY_SIZE(vcpu_44x->shadow_refs); i++)
vcpu_44x->shadow_refs[i].gtlb_index = -1;
return 0;
}
/* 'linear_address' is actually an encoding of AS|PID|EADDR . */
int kvmppc_core_vcpu_translate(struct kvm_vcpu *vcpu,
struct kvm_translation *tr)
{
int index;
gva_t eaddr;
u8 pid;
u8 as;
eaddr = tr->linear_address;
pid = (tr->linear_address >> 32) & 0xff;
as = (tr->linear_address >> 40) & 0x1;
index = kvmppc_44x_tlb_index(vcpu, eaddr, pid, as);
if (index == -1) {
tr->valid = 0;
return 0;
}
tr->physical_address = kvmppc_mmu_xlate(vcpu, index, eaddr);
/* XXX what does "writeable" and "usermode" even mean? */
tr->valid = 1;
return 0;
}
struct kvm_vcpu *kvmppc_core_vcpu_create(struct kvm *kvm, unsigned int id)
{
struct kvmppc_vcpu_44x *vcpu_44x;
struct kvm_vcpu *vcpu;
int err;
vcpu_44x = kmem_cache_zalloc(kvm_vcpu_cache, GFP_KERNEL);
if (!vcpu_44x) {
err = -ENOMEM;
goto out;
}
vcpu = &vcpu_44x->vcpu;
err = kvm_vcpu_init(vcpu, kvm, id);
if (err)
goto free_vcpu;
vcpu->arch.shared = (void*)__get_free_page(GFP_KERNEL|__GFP_ZERO);
if (!vcpu->arch.shared)
goto uninit_vcpu;
return vcpu;
uninit_vcpu:
kvm_vcpu_uninit(vcpu);
free_vcpu:
kmem_cache_free(kvm_vcpu_cache, vcpu_44x);
out:
return ERR_PTR(err);
}
void kvmppc_core_vcpu_free(struct kvm_vcpu *vcpu)
{
struct kvmppc_vcpu_44x *vcpu_44x = to_44x(vcpu);
free_page((unsigned long)vcpu->arch.shared);
kvm_vcpu_uninit(vcpu);
kmem_cache_free(kvm_vcpu_cache, vcpu_44x);
}
static int __init kvmppc_44x_init(void)
{
int r;
r = kvmppc_booke_init();
if (r)
return r;
return kvm_init(NULL, sizeof(struct kvmppc_vcpu_44x), 0, THIS_MODULE);
}
static void __exit kvmppc_44x_exit(void)
{
kvmppc_booke_exit();
}
module_init(kvmppc_44x_init);
module_exit(kvmppc_44x_exit);