diff options
| -rw-r--r-- | arch/s390/kvm/kvm-s390.c | 36 |
1 files changed, 31 insertions, 5 deletions
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c index f4d56e9939c..86567e174fd 100644 --- a/arch/s390/kvm/kvm-s390.c +++ b/arch/s390/kvm/kvm-s390.c @@ -657,6 +657,8 @@ int kvm_arch_set_memory_region(struct kvm *kvm, struct kvm_memory_slot old, int user_alloc) { + int i; + /* A few sanity checks. We can have exactly one memory slot which has to start at guest virtual zero and which has to be located at a page boundary in userland and which has to end at a page boundary. @@ -664,7 +666,7 @@ int kvm_arch_set_memory_region(struct kvm *kvm, vmas. It is okay to mmap() and munmap() stuff in this slot after doing this call at any time */ - if (mem->slot) + if (mem->slot || kvm->arch.guest_memsize) return -EINVAL; if (mem->guest_phys_addr) @@ -676,15 +678,39 @@ int kvm_arch_set_memory_region(struct kvm *kvm, if (mem->memory_size & (PAGE_SIZE - 1)) return -EINVAL; + if (!user_alloc) + return -EINVAL; + + /* lock all vcpus */ + for (i = 0; i < KVM_MAX_VCPUS; ++i) { + if (!kvm->vcpus[i]) + continue; + if (!mutex_trylock(&kvm->vcpus[i]->mutex)) + goto fail_out; + } + kvm->arch.guest_origin = mem->userspace_addr; kvm->arch.guest_memsize = mem->memory_size; - /* FIXME: we do want to interrupt running CPUs and update their memory - configuration now to avoid race conditions. But hey, changing the - memory layout while virtual CPUs are running is usually bad - programming practice. */ + /* update sie control blocks, and unlock all vcpus */ + for (i = 0; i < KVM_MAX_VCPUS; ++i) { + if (kvm->vcpus[i]) { + kvm->vcpus[i]->arch.sie_block->gmsor = + kvm->arch.guest_origin; + kvm->vcpus[i]->arch.sie_block->gmslm = + kvm->arch.guest_memsize + + kvm->arch.guest_origin + + VIRTIODESCSPACE - 1ul; + mutex_unlock(&kvm->vcpus[i]->mutex); + } + } return 0; + +fail_out: + for (; i >= 0; i--) + mutex_unlock(&kvm->vcpus[i]->mutex); + return -EINVAL; } void kvm_arch_flush_shadow(struct kvm *kvm) |