Merge branch 'kvm-guestmemfd' into HEAD

[linux-2.6-block.git] / virt / kvm / guest_memfd.c

diff --git a/virt/kvm/guest_memfd.c b/virt/kvm/guest_memfd.c
index e65f4170425c4cd7460185dccf288d4b794d4d68..b992723961195f87ce898222a2635d2f43fcfa7c 100644 (file)
--- a/virt/kvm/guest_memfd.c
+++ b/virt/kvm/guest_memfd.c
@@ -237,19 +237,15 @@ static int kvm_gmem_release(struct inode *inode, struct file *file)
        return 0;
 }
 
-static struct file *kvm_gmem_get_file(struct kvm_memory_slot *slot)
+static inline struct file *kvm_gmem_get_file(struct kvm_memory_slot *slot)
 {
-       struct file *file;
-
-       rcu_read_lock();
-
-       file = rcu_dereference(slot->gmem.file);
-       if (file && !get_file_rcu(file))
-               file = NULL;
-
-       rcu_read_unlock();
-
-       return file;
+       /*
+        * Do not return slot->gmem.file if it has already been closed;
+        * there might be some time between the last fput() and when
+        * kvm_gmem_release() clears slot->gmem.file, and you do not
+        * want to spin in the meanwhile.
+        */
+       return get_file_active(&slot->gmem.file);
 }
 
 static struct file_operations kvm_gmem_fops = {