1 files changed, 23 insertions, 12 deletions

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index c6ee8f1063ff..fce61991213c 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -6677,28 +6677,36 @@ static ssize_t btrfs_direct_IO(int rw, struct kiocb *iocb,
         struct inode *inode = file->f_mapping->host;
         size_t count = 0;
         int flags = 0;
-        bool wakeup = false;
+        bool wakeup = true;
+        bool relock = false;
         ssize_t ret;
 
         if (check_direct_IO(BTRFS_I(inode)->root, rw, iocb, iov,
                             offset, nr_segs))
                 return 0;
 
+        atomic_inc(&inode->i_dio_count);
+        smp_mb__after_atomic_inc();
+
         if (rw & WRITE) {
                 count = iov_length(iov, nr_segs);
+                /*
+                 * If the write DIO is beyond the EOF, we need update
+                 * the isize, but it is protected by i_mutex. So we can
+                 * not unlock the i_mutex at this case.
+                 */
+                if (offset + count <= inode->i_size) {
+                        mutex_unlock(&inode->i_mutex);
+                        relock = true;
+                }
                 ret = btrfs_delalloc_reserve_space(inode, count);
                 if (ret)
-                        return ret;
-        } else {
-                atomic_inc(&inode->i_dio_count);
-                smp_mb__after_atomic_inc();
-                if (unlikely(test_bit(BTRFS_INODE_READDIO_NEED_LOCK,
-                                      &BTRFS_I(inode)->runtime_flags))) {
-                        inode_dio_done(inode);
-                        flags = DIO_LOCKING | DIO_SKIP_HOLES;
-                } else {
-                        wakeup = true;
-                }
+                        goto out;
+        } else if (unlikely(test_bit(BTRFS_INODE_READDIO_NEED_LOCK,
+                                     &BTRFS_I(inode)->runtime_flags))) {
+                inode_dio_done(inode);
+                flags = DIO_LOCKING | DIO_SKIP_HOLES;
+                wakeup = false;
         }
 
         ret = __blockdev_direct_IO(rw, iocb, inode,
@@ -6717,8 +6725,11 @@ static ssize_t btrfs_direct_IO(int rw, struct kiocb *iocb,
                 }
                 btrfs_delalloc_release_metadata(inode, 0);
         }
+out:
         if (wakeup)
                 inode_dio_done(inode);
+        if (relock)
+                mutex_lock(&inode->i_mutex);
 
         return ret;
 }