Hello, so I've now hit a xfstests failure for UDF which is caused by the implementation of SEEK_HOLE / SEEK_DATA in generic_file_llseek(). UDF uses that function as its .llseek method but it supports holes as any other unix filesystem (e.g. ext2). The test in xfstests assumes that when it creates a file by pwrite(fd, buf, bufsz, off), then SEEK_DATA on offset 0 should return 'off' (off is reasonably rounded) but that's not true for the implementation in generic_file_llseek(). Now I'm not so much interested in that test itself - that can be tweaked to detect that case. But I rather wanted to ask - how useful is it to implement SEEK_HOLE / SEEK_DATA the way it is in generic_file_llseek()? Because it seems to me that any serious user will have to detect whether SEEK_HOLE / SEEK_DATA works reasonably and if not, fall back to some heuristic anyway. So why bother inventing bogus values in generic_file_llseek and thus making detection of working implementation harder? Honza -- Jan Kara <jack@xxxxxxx> SUSE Labs, CR -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
