f2fs: add f2fs_ioc_get_compress_blocks

This patch adds f2fs_ioc_get_compress_blocks() to provide a common
f2fs_get_compress_blocks().
Signed-off-by: Sheng Yong <shengyong@oppo.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

fs/f2fs/file.c

@@ -3377,18 +3377,29 @@ static int f2fs_ioc_setfslabel(struct file *filp, unsigned long arg)
 	return err;
 }
 
-static int f2fs_get_compress_blocks(struct file *filp, unsigned long arg)
+static int f2fs_get_compress_blocks(struct inode *inode, __u64 *blocks)
 {
-	struct inode *inode = file_inode(filp);
-	__u64 blocks;
-
 	if (!f2fs_sb_has_compression(F2FS_I_SB(inode)))
 		return -EOPNOTSUPP;
 
 	if (!f2fs_compressed_file(inode))
 		return -EINVAL;
 
-	blocks = atomic_read(&F2FS_I(inode)->i_compr_blocks);
+	*blocks = atomic_read(&F2FS_I(inode)->i_compr_blocks);
+
+	return 0;
+}
+
+static int f2fs_ioc_get_compress_blocks(struct file *filp, unsigned long arg)
+{
+	struct inode *inode = file_inode(filp);
+	__u64 blocks;
+	int ret;
+
+	ret = f2fs_get_compress_blocks(inode, &blocks);
+	if (ret < 0)
+		return ret;
+
 	return put_user(blocks, (u64 __user *)arg);
 }
 
@@ -4240,7 +4251,7 @@ static long __f2fs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 	case FS_IOC_SETFSLABEL:
 		return f2fs_ioc_setfslabel(filp, arg);
 	case F2FS_IOC_GET_COMPRESS_BLOCKS:
-		return f2fs_get_compress_blocks(filp, arg);
+		return f2fs_ioc_get_compress_blocks(filp, arg);
 	case F2FS_IOC_RELEASE_COMPRESS_BLOCKS:
 		return f2fs_release_compress_blocks(filp, arg);
 	case F2FS_IOC_RESERVE_COMPRESS_BLOCKS: