KVM: PPC: Rework H_PUT_TCE/H_GET_TCE handlers

This reworks the existing H_PUT_TCE/H_GET_TCE handlers to have following
patches applied nicer.

This moves the ioba boundaries check to a helper and adds a check for
least bits which have to be zeros.

The patch is pretty mechanical (only check for least ioba bits is added)
so no change in behaviour is expected.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This commit is contained in:
Alexey Kardashevskiy 2016-02-15 12:55:04 +11:00 committed by Paul Mackerras
parent e9ab1a1caf
commit fcbb2ce672
1 changed files with 71 additions and 38 deletions

View File

@ -35,71 +35,104 @@
#include <asm/ppc-opcode.h>
#include <asm/kvm_host.h>
#include <asm/udbg.h>
#include <asm/iommu.h>
#define TCES_PER_PAGE (PAGE_SIZE / sizeof(u64))
/*
* Finds a TCE table descriptor by LIOBN.
*
* WARNING: This will be called in real or virtual mode on HV KVM and virtual
* mode on PR KVM
*/
static struct kvmppc_spapr_tce_table *kvmppc_find_table(struct kvm_vcpu *vcpu,
unsigned long liobn)
{
struct kvm *kvm = vcpu->kvm;
struct kvmppc_spapr_tce_table *stt;
list_for_each_entry(stt, &kvm->arch.spapr_tce_tables, list)
if (stt->liobn == liobn)
return stt;
return NULL;
}
/*
* Validates IO address.
*
* WARNING: This will be called in real-mode on HV KVM and virtual
* mode on PR KVM
*/
static long kvmppc_ioba_validate(struct kvmppc_spapr_tce_table *stt,
unsigned long ioba, unsigned long npages)
{
unsigned long mask = (1ULL << IOMMU_PAGE_SHIFT_4K) - 1;
unsigned long idx = ioba >> IOMMU_PAGE_SHIFT_4K;
unsigned long size = stt->window_size >> IOMMU_PAGE_SHIFT_4K;
if ((ioba & mask) || (idx + npages > size) || (idx + npages < idx))
return H_PARAMETER;
return H_SUCCESS;
}
/* WARNING: This will be called in real-mode on HV KVM and virtual
* mode on PR KVM
*/
long kvmppc_h_put_tce(struct kvm_vcpu *vcpu, unsigned long liobn,
unsigned long ioba, unsigned long tce)
{
struct kvm *kvm = vcpu->kvm;
struct kvmppc_spapr_tce_table *stt;
struct kvmppc_spapr_tce_table *stt = kvmppc_find_table(vcpu, liobn);
long ret;
unsigned long idx;
struct page *page;
u64 *tbl;
/* udbg_printf("H_PUT_TCE(): liobn=0x%lx ioba=0x%lx, tce=0x%lx\n", */
/* liobn, ioba, tce); */
list_for_each_entry(stt, &kvm->arch.spapr_tce_tables, list) {
if (stt->liobn == liobn) {
unsigned long idx = ioba >> SPAPR_TCE_SHIFT;
struct page *page;
u64 *tbl;
if (!stt)
return H_TOO_HARD;
/* udbg_printf("H_PUT_TCE: liobn 0x%lx => stt=%p window_size=0x%x\n", */
/* liobn, stt, stt->window_size); */
if (ioba >= stt->window_size)
return H_PARAMETER;
ret = kvmppc_ioba_validate(stt, ioba, 1);
if (ret != H_SUCCESS)
return ret;
page = stt->pages[idx / TCES_PER_PAGE];
tbl = (u64 *)page_address(page);
idx = ioba >> SPAPR_TCE_SHIFT;
page = stt->pages[idx / TCES_PER_PAGE];
tbl = (u64 *)page_address(page);
/* FIXME: Need to validate the TCE itself */
/* udbg_printf("tce @ %p\n", &tbl[idx % TCES_PER_PAGE]); */
tbl[idx % TCES_PER_PAGE] = tce;
return H_SUCCESS;
}
}
/* FIXME: Need to validate the TCE itself */
/* udbg_printf("tce @ %p\n", &tbl[idx % TCES_PER_PAGE]); */
tbl[idx % TCES_PER_PAGE] = tce;
/* Didn't find the liobn, punt it to userspace */
return H_TOO_HARD;
return H_SUCCESS;
}
EXPORT_SYMBOL_GPL(kvmppc_h_put_tce);
long kvmppc_h_get_tce(struct kvm_vcpu *vcpu, unsigned long liobn,
unsigned long ioba)
{
struct kvm *kvm = vcpu->kvm;
struct kvmppc_spapr_tce_table *stt;
struct kvmppc_spapr_tce_table *stt = kvmppc_find_table(vcpu, liobn);
long ret;
unsigned long idx;
struct page *page;
u64 *tbl;
list_for_each_entry(stt, &kvm->arch.spapr_tce_tables, list) {
if (stt->liobn == liobn) {
unsigned long idx = ioba >> SPAPR_TCE_SHIFT;
struct page *page;
u64 *tbl;
if (!stt)
return H_TOO_HARD;
if (ioba >= stt->window_size)
return H_PARAMETER;
ret = kvmppc_ioba_validate(stt, ioba, 1);
if (ret != H_SUCCESS)
return ret;
page = stt->pages[idx / TCES_PER_PAGE];
tbl = (u64 *)page_address(page);
idx = ioba >> SPAPR_TCE_SHIFT;
page = stt->pages[idx / TCES_PER_PAGE];
tbl = (u64 *)page_address(page);
vcpu->arch.gpr[4] = tbl[idx % TCES_PER_PAGE];
return H_SUCCESS;
}
}
vcpu->arch.gpr[4] = tbl[idx % TCES_PER_PAGE];
/* Didn't find the liobn, punt it to userspace */
return H_TOO_HARD;
return H_SUCCESS;
}
EXPORT_SYMBOL_GPL(kvmppc_h_get_tce);