- support QEMU interface for initial VM Write Protect
- QEMU Dirty bit map log retrieval
Signed-off-by: Mario Smarduch <m.smarduch@xxxxxxxxxxx>
---
arch/arm/kvm/arm.c | 62 +++++++++++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 61 insertions(+), 1 deletion(-)
diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c
index bd18bb8..9076e3d 100644
--- a/arch/arm/kvm/arm.c
+++ b/arch/arm/kvm/arm.c
@@ -241,6 +241,8 @@ void kvm_arch_commit_memory_region(struct kvm *kvm,
const struct kvm_memory_slot *old,
enum kvm_mr_change change)
{
+ if ((change != KVM_MR_DELETE) && (mem->flags & KVM_MEM_LOG_DIRTY_PAGES))
+ kvm_mmu_slot_remove_write_access(kvm, mem->slot);
}
void kvm_arch_flush_shadow_all(struct kvm *kvm)
@@ -773,9 +775,67 @@ long kvm_arch_vcpu_ioctl(struct file *filp,
}
}
+/*
+ * Walks the memslot dirty bitmap, write protects dirty pages for next rount,
+ * and stores the dirty bitmap fo QEMU retrieval.
+ *
+ */
int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm, struct kvm_dirty_log *log)
{
- return -EINVAL;
+ int r;
+ struct kvm_memory_slot *memslot;
+ unsigned long n, i;
+ unsigned long *dirty_bitmap;
+ unsigned long *dirty_bitmap_buffer;
+ bool is_dirty = false;
+ gfn_t offset;
+
+ mutex_lock(&kvm->slots_lock);
+ r = -EINVAL;
+
+ if (log->slot >= KVM_USER_MEM_SLOTS)
+ goto out;
+
+ memslot = id_to_memslot(kvm->memslots, log->slot);
+ dirty_bitmap = memslot->dirty_bitmap;
+
+ r = -ENOENT;
+ if (!dirty_bitmap)
+ goto out;
+
+ n = kvm_dirty_bitmap_bytes(memslot);
+ dirty_bitmap_buffer = dirty_bitmap + n / sizeof(long);
+ memset(dirty_bitmap_buffer, 0, n);
+
+ spin_lock(&kvm->mmu_lock);
+ for (i = 0; i < n / sizeof(long); i++) {
+ unsigned long mask;
+
+ if (!dirty_bitmap[i])
+ continue;
+
+ is_dirty = true;
+ offset = i * BITS_PER_LONG;
+ kvm_mmu_write_protect_pt_masked(kvm, memslot, offset,
+ dirty_bitmap[i]);
+ mask = dirty_bitmap[i];
+ dirty_bitmap_buffer[i] = mask;
+ dirty_bitmap[i] = 0;
+ }
+
+ if (is_dirty)
+ kvm_tlb_flush_vmid(kvm);
+
+ spin_unlock(&kvm->mmu_lock);
+ r = -EFAULT;
+
+ if (copy_to_user(log->dirty_bitmap, dirty_bitmap_buffer, n))
+ goto out;
+
+ r = 0;
+out:
+ mutex_unlock(&kvm->slots_lock);
+ return r;
}
static int kvm_vm_ioctl_set_device_addr(struct kvm *kvm,
--
1.7.9.5
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