KVM: Mapping IOMMU pages after updating memslot

In kvm_iommu_map_pages(), we need to know the page size via call
kvm_host_page_size(). And it will check whether the target slot
is valid before return the right page size.
Currently, we will map the iommu pages when creating a new slot.
But we call kvm_iommu_map_pages() during preparing the new slot.
At that time, the new slot is not visible by domain(still in preparing).
So we cannot get the right page size from kvm_host_page_size() and
this will break the IOMMU super page logic.
The solution is to map the iommu pages after we insert the new slot
into domain.

Signed-off-by: Yang Zhang <yang.z.zhang@Intel.com>
Tested-by: Patrick Lu <patrick.lu@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Yang Zhang 2013-10-24 09:56:39 +08:00 committed by Paolo Bonzini
parent a294c9bbd0
commit e0230e1327

View File

@ -873,21 +873,6 @@ int __kvm_set_memory_region(struct kvm *kvm,
goto out_free;
}
/*
* IOMMU mapping: New slots need to be mapped. Old slots need to be
* un-mapped and re-mapped if their base changes. Since base change
* unmapping is handled above with slot deletion, mapping alone is
* needed here. Anything else the iommu might care about for existing
* slots (size changes, userspace addr changes and read-only flag
* changes) is disallowed above, so any other attribute changes getting
* here can be skipped.
*/
if ((change == KVM_MR_CREATE) || (change == KVM_MR_MOVE)) {
r = kvm_iommu_map_pages(kvm, &new);
if (r)
goto out_slots;
}
/* actual memory is freed via old in kvm_free_physmem_slot below */
if (change == KVM_MR_DELETE) {
new.dirty_bitmap = NULL;
@ -901,6 +886,20 @@ int __kvm_set_memory_region(struct kvm *kvm,
kvm_free_physmem_slot(&old, &new);
kfree(old_memslots);
/*
* IOMMU mapping: New slots need to be mapped. Old slots need to be
* un-mapped and re-mapped if their base changes. Since base change
* unmapping is handled above with slot deletion, mapping alone is
* needed here. Anything else the iommu might care about for existing
* slots (size changes, userspace addr changes and read-only flag
* changes) is disallowed above, so any other attribute changes getting
* here can be skipped.
*/
if ((change == KVM_MR_CREATE) || (change == KVM_MR_MOVE)) {
r = kvm_iommu_map_pages(kvm, &new);
return r;
}
return 0;
out_slots: