diff options
| author | Suraj Jitindar Singh <sjitindarsingh@gmail.com> | 2018-12-14 16:29:07 +1100 |
|---|---|---|
| committer | Paul Mackerras <paulus@ozlabs.org> | 2018-12-17 11:33:50 +1100 |
| commit | cc6929cc842cceee714c66cd55346b1a9f114a98 (patch) | |
| tree | 0a320d69ccc82539eaccb2dbd2ea3107534e9430 | |
| parent | dceadcf91b2e0971abe706b6d605ed25de61db0e (diff) | |
KVM: PPC: Update kvmppc_st and kvmppc_ld to use quadrants
The functions kvmppc_st and kvmppc_ld are used to access guest memory
from the host using a guest effective address. They do so by translating
through the process table to obtain a guest real address and then using
kvm_read_guest or kvm_write_guest to make the access with the guest real
address.
This method of access however only works for L1 guests and will give the
incorrect results for a nested guest.
We can however use the store_to_eaddr and load_from_eaddr kvmppc_ops to
perform the access for a nested guesti (and a L1 guest). So attempt this
method first and fall back to the old method if this fails and we aren't
running a nested guest.
At this stage there is no fall back method to perform the access for a
nested guest and this is left as a future improvement. For now we will
return to the nested guest and rely on the fact that a translation
should be faulted in before retrying the access.
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
| -rw-r--r-- | arch/powerpc/kvm/powerpc.c | 18 |
1 files changed, 16 insertions, 2 deletions
diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c index 18dd98f35ac1..ec9cbf9db364 100644 --- a/arch/powerpc/kvm/powerpc.c +++ b/arch/powerpc/kvm/powerpc.c @@ -331,10 +331,17 @@ int kvmppc_st(struct kvm_vcpu *vcpu, ulong *eaddr, int size, void *ptr, { ulong mp_pa = vcpu->arch.magic_page_pa & KVM_PAM & PAGE_MASK; struct kvmppc_pte pte; - int r; + int r = -EINVAL; vcpu->stat.st++; + if (vcpu->kvm->arch.kvm_ops && vcpu->kvm->arch.kvm_ops->store_to_eaddr) + r = vcpu->kvm->arch.kvm_ops->store_to_eaddr(vcpu, eaddr, ptr, + size); + + if ((!r) || (r == -EAGAIN)) + return r; + r = kvmppc_xlate(vcpu, *eaddr, data ? XLATE_DATA : XLATE_INST, XLATE_WRITE, &pte); if (r < 0) @@ -367,10 +374,17 @@ int kvmppc_ld(struct kvm_vcpu *vcpu, ulong *eaddr, int size, void *ptr, { ulong mp_pa = vcpu->arch.magic_page_pa & KVM_PAM & PAGE_MASK; struct kvmppc_pte pte; - int rc; + int rc = -EINVAL; vcpu->stat.ld++; + if (vcpu->kvm->arch.kvm_ops && vcpu->kvm->arch.kvm_ops->load_from_eaddr) + rc = vcpu->kvm->arch.kvm_ops->load_from_eaddr(vcpu, eaddr, ptr, + size); + + if ((!rc) || (rc == -EAGAIN)) + return rc; + rc = kvmppc_xlate(vcpu, *eaddr, data ? XLATE_DATA : XLATE_INST, XLATE_READ, &pte); if (rc) |