Those are suitable for error detection for relatively short files, in the kilobyte range. They can be used for error detection in big files only if you compute one per page, e.g. one for each 4kB page.
They are not useful as file identifiers. I have found multiple CRC32 collisions even in a single directory (a big one, with around ten thousand files).
For error detection in a big file, you need at least some 64-bit CRC, though SipHash is likely to be a better choice than a CRC.
For identifying uniquely a file in a multi-TB file system, which may have many millions of files, even a 64-bit hash is not good enough, a hash of 128 bits or more is needed to make negligible the probability of collisions. I have verified this experimentally, finding several 64-bit file hash collisions in my file systems.
