KVM: cleanup: remove kvm_get_dirty_log()

kvm_get_dirty_log() is a helper function for kvm_vm_ioctl_get_dirty_log() which
is currently used by ia64 and ppc and the following is what it is doing:

  - sanity checks
  - bitmap scan to check if the slot is dirty
  - copy_to_user()

Considering the fact that x86 is not using this anymore and sanity checks must
be done before kvm_ia64_sync_dirty_log(), we can say that this is not working
for code sharing effectively. So we just remove this.

Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Signed-off-by: Avi Kivity <avi@redhat.com>

diff --git a/arch/ia64/kvm/kvm-ia64.c b/arch/ia64/kvm/kvm-ia64.c
index 5cb58655cd5f98d482895b51e9251852a70c1236..da0c133ea7f88deea4c5fc19beb4936ac5de29f8 100644 (file)
--- a/arch/ia64/kvm/kvm-ia64.c
+++ b/arch/ia64/kvm/kvm-ia64.c
@@ -1818,10 +1818,10 @@ static void kvm_ia64_sync_dirty_log(struct kvm *kvm,
 int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm,
                struct kvm_dirty_log *log)
 {
-       int r;
+       int r, i;
        unsigned long n;
        struct kvm_memory_slot *memslot;
-       int is_dirty = 0;
+       unsigned long is_dirty = 0;
 
        mutex_lock(&kvm->slots_lock);
 
@@ -1835,15 +1835,23 @@ int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm,
                goto out;
 
        kvm_ia64_sync_dirty_log(kvm, memslot);
-       r = kvm_get_dirty_log(kvm, log, &is_dirty);
-       if (r)
-               goto out;
+
+       n = kvm_dirty_bitmap_bytes(memslot);
+
+       for (i = 0; !is_dirty && i < n/sizeof(long); ++i)
+               is_dirty = memslot->dirty_bitmap[i];
 
        /* If nothing is dirty, don't bother messing with page tables. */
        if (is_dirty) {
                kvm_flush_remote_tlbs(kvm);
-               n = kvm_dirty_bitmap_bytes(memslot);
+               r = -EFAULT;
+               if (copy_to_user(log->dirty_bitmap, memslot->dirty_bitmap, n))
+                       goto out;
                memset(memslot->dirty_bitmap, 0, n);
+       } else {
+               r = -EFAULT;
+               if (clear_user(log->dirty_bitmap, n))
+                       goto out;
        }
        r = 0;
 out:

diff --git a/arch/powerpc/kvm/book3s.c b/arch/powerpc/kvm/book3s.c
index 801d9f3c70aec7ab9d3dd057f882d5b632695c2d..bea6f7cf81efb3682aa4546681b041694537f95d 100644 (file)
--- a/arch/powerpc/kvm/book3s.c
+++ b/arch/powerpc/kvm/book3s.c
@@ -1185,28 +1185,43 @@ int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm,
        struct kvm_memory_slot *memslot;
        struct kvm_vcpu *vcpu;
        ulong ga, ga_end;
-       int is_dirty = 0;
-       int r;
+       unsigned long is_dirty = 0;
+       int r, i;
        unsigned long n;
 
        mutex_lock(&kvm->slots_lock);
 
-       r = kvm_get_dirty_log(kvm, log, &is_dirty);
-       if (r)
+       r = -EINVAL;
+       if (log->slot >= KVM_MEMORY_SLOTS)
+               goto out;
+
+       memslot = &kvm->memslots->memslots[log->slot];
+       r = -ENOENT;
+       if (!memslot->dirty_bitmap)
                goto out;
 
+       n = kvm_dirty_bitmap_bytes(memslot);
+
+       for (i = 0; !is_dirty && i < n/sizeof(long); ++i)
+               is_dirty = memslot->dirty_bitmap[i];
+
        /* If nothing is dirty, don't bother messing with page tables. */
        if (is_dirty) {
-               memslot = &kvm->memslots->memslots[log->slot];
-
                ga = memslot->base_gfn << PAGE_SHIFT;
                ga_end = ga + (memslot->npages << PAGE_SHIFT);
 
                kvm_for_each_vcpu(n, vcpu, kvm)
                        kvmppc_mmu_pte_pflush(vcpu, ga, ga_end);
 
-               n = kvm_dirty_bitmap_bytes(memslot);
+               r = -EFAULT;
+               if (copy_to_user(log->dirty_bitmap, memslot->dirty_bitmap, n))
+                       goto out;
+
                memset(memslot->dirty_bitmap, 0, n);
+       } else {
+               r = -EFAULT;
+               if (clear_user(log->dirty_bitmap, n))
+                       goto out;
        }
 
        r = 0;

diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index e796326f364628935e690b20f09c6e606ad7eb4e..b51e6b2fcb47b0c77a0adfc203c72f30b9af20e5 100644 (file)
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -336,8 +336,6 @@ long kvm_arch_vcpu_ioctl(struct file *filp,
 
 int kvm_dev_ioctl_check_extension(long ext);
 
-int kvm_get_dirty_log(struct kvm *kvm,
-                       struct kvm_dirty_log *log, int *is_dirty);
 int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm,
                                struct kvm_dirty_log *log);
 

diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index ec2e3c6ac7ed9985cc7505a502c6c1c357d3fc33..9eaea28e0da5201c13c95280f5e493abb4e75c41 100644 (file)
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -773,40 +773,6 @@ int kvm_vm_ioctl_set_memory_region(struct kvm *kvm,
        return kvm_set_memory_region(kvm, mem, user_alloc);
 }
 
-int kvm_get_dirty_log(struct kvm *kvm,
-                       struct kvm_dirty_log *log, int *is_dirty)
-{
-       struct kvm_memory_slot *memslot;
-       int r, i;
-       unsigned long n;
-       unsigned long any = 0;
-
-       r = -EINVAL;
-       if (log->slot >= KVM_MEMORY_SLOTS)
-               goto out;
-
-       memslot = &kvm->memslots->memslots[log->slot];
-       r = -ENOENT;
-       if (!memslot->dirty_bitmap)
-               goto out;
-
-       n = kvm_dirty_bitmap_bytes(memslot);
-
-       for (i = 0; !any && i < n/sizeof(long); ++i)
-               any = memslot->dirty_bitmap[i];
-
-       r = -EFAULT;
-       if (copy_to_user(log->dirty_bitmap, memslot->dirty_bitmap, n))
-               goto out;
-
-       if (any)
-               *is_dirty = 1;
-
-       r = 0;
-out:
-       return r;
-}
-
 void kvm_disable_largepages(void)
 {
        largepages_enabled = false;