ext4: use generic_file_fsync() in ext4_file_fsync() in nojournal mode

Just use the generic function instead of duplicating it.  We only need
to reshuffle the read-only check a bit (which is there to prevent
writing to a filesystem which has been remounted read-only after error
I assume).

Reviewed-by: Zheng Liu <wenqing.lz@taobao.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

1 files changed, 11 insertions, 36 deletions

diff --git a/fs/ext4/fsync.c b/fs/ext4/fsync.c
index dcc881b30849..6019bd449576 100644
--- a/fs/ext4/fsync.c
+++ b/fs/ext4/fsync.c
@@ -73,32 +73,6 @@ static int ext4_sync_parent(struct inode *inode)
         return ret;
 }
 
-/**
- * __sync_file - generic_file_fsync without the locking and filemap_write
- * @inode:      inode to sync
- * @datasync:   only sync essential metadata if true
- *
- * This is just generic_file_fsync without the locking.  This is needed for
- * nojournal mode to make sure this inodes data/metadata makes it to disk
- * properly.  The i_mutex should be held already.
- */
-static int __sync_inode(struct inode *inode, int datasync)
-{
-        int err;
-        int ret;
-
-        ret = sync_mapping_buffers(inode->i_mapping);
-        if (!(inode->i_state & I_DIRTY))
-                return ret;
-        if (datasync && !(inode->i_state & I_DIRTY_DATASYNC))
-                return ret;
-
-        err = sync_inode_metadata(inode, 1);
-        if (ret == 0)
-                ret = err;
-        return ret;
-}
-
 /*
  * akpm: A new design for ext4_sync_file().
  *
@@ -116,7 +90,7 @@ int ext4_sync_file(struct file *file, loff_t start, loff_t end, int datasync)
         struct inode *inode = file->f_mapping->host;
         struct ext4_inode_info *ei = EXT4_I(inode);
         journal_t *journal = EXT4_SB(inode->i_sb)->s_journal;
-        int ret, err;
+        int ret = 0, err;
         tid_t commit_tid;
         bool needs_barrier = false;
 
@@ -124,21 +98,21 @@ int ext4_sync_file(struct file *file, loff_t start, loff_t end, int datasync)
 
         trace_ext4_sync_file_enter(file, datasync);
 
-        ret = filemap_write_and_wait_range(inode->i_mapping, start, end);
-        if (ret)
-                return ret;
-        mutex_lock(&inode->i_mutex);
-
         if (inode->i_sb->s_flags & MS_RDONLY)
-                goto out;
+                goto out_trace;
 
         if (!journal) {
-                ret = __sync_inode(inode, datasync);
+                ret = generic_file_fsync(file, start, end, datasync);
                 if (!ret && !hlist_empty(&inode->i_dentry))
                         ret = ext4_sync_parent(inode);
-                goto out;
+                goto out_trace;
         }
 
+        ret = filemap_write_and_wait_range(inode->i_mapping, start, end);
+        if (ret)
+                return ret;
+        mutex_lock(&inode->i_mutex);
+
         /*
          * data=writeback,ordered:
          *  The caller's filemap_fdatawrite()/wait will sync the data.
@@ -168,8 +142,9 @@ int ext4_sync_file(struct file *file, loff_t start, loff_t end, int datasync)
                 if (!ret)
                         ret = err;
         }
- out:
+out:
         mutex_unlock(&inode->i_mutex);
+out_trace:
         trace_ext4_sync_file_exit(inode, ret);
         return ret;
 }