extern ino_t sysv_inode_by_name(struct dentry *);
-extern struct inode_operations sysv_file_inode_operations;
-extern struct inode_operations sysv_dir_inode_operations;
-extern struct inode_operations sysv_fast_symlink_inode_operations;
+extern const struct inode_operations sysv_file_inode_operations;
+extern const struct inode_operations sysv_dir_inode_operations;
+extern const struct inode_operations sysv_fast_symlink_inode_operations;
extern const struct file_operations sysv_file_operations;
extern const struct file_operations sysv_dir_operations;
extern const struct address_space_operations sysv_aops;