f2fs: add offset check routine before punch_hole() in f2fs_fallocate()

In the punch_hole(), if offset bigger than inode size, it returns SUCCESS.
Then f2fs_fallocate() will update time and dirty mark.
In that case, inode has not been modified actually.
So I have added offset check routine that prevent to call the punch_hole().

Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

fs/f2fs/file.c

@@ -718,10 +718,6 @@ static int punch_hole(struct inode *inode, loff_t offset, loff_t len)
 	if (!S_ISREG(inode->i_mode))
 		return -EOPNOTSUPP;
 
-	/* skip punching hole beyond i_size */
-	if (offset >= inode->i_size)
-		return ret;
-
 	if (f2fs_has_inline_data(inode)) {
 		ret = f2fs_convert_inline_inode(inode);
 		if (ret)
@@ -830,15 +826,19 @@ static long f2fs_fallocate(struct file *file, int mode,
 				loff_t offset, loff_t len)
 {
 	struct inode *inode = file_inode(file);
-	long ret;
+	long ret = 0;
 
 	if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE))
 		return -EOPNOTSUPP;
 
 	mutex_lock(&inode->i_mutex);
 
-	if (mode & FALLOC_FL_PUNCH_HOLE)
+	if (mode & FALLOC_FL_PUNCH_HOLE) {
+		if (offset >= inode->i_size)
+			goto out;
+
 		ret = punch_hole(inode, offset, len);
+	}
 	else
 		ret = expand_inode_data(inode, offset, len, mode);
 
@@ -847,6 +847,7 @@ static long f2fs_fallocate(struct file *file, int mode,
 		mark_inode_dirty(inode);
 	}
 
+out:
 	mutex_unlock(&inode->i_mutex);
 
 	trace_f2fs_fallocate(inode, mode, offset, len, ret);