svn commit: r246289 - head/sys/ufs/ffs

[Bruce Evans]

On Sun, 3 Feb 2013, Pedro Giffuni wrote:

> (Moving the discussion to freebsd-fs)

>> Da: Bruce Evans 
>>
> ...
>>>  Just a note that clang actually warned about this one.
>>>  It has a few more similar warnings for ufs/ffs code.
>>
>> I wondered how the DIP macro hid the warning.
>>  
>
> The comparison is perfectly legal for UFS1 so perhaps
> gcc gives the "benefit of the doubt" to avoid false positives.
> 
>> Perhaps the larger bugs pointed to this warning were lost in translation:
>> - di_blocks overflows for ffs1.  This is now physically possible.
>> ...
> Surely not anywhere near a complete solution but perhaps it wouldn't
> be incompatible to change i_blocks and friends to be unsigned in UFS1.
> That is something that remains to be completed in ext2fs, but according
> to fsx there are bigger problems there at this time.

That only gives 1 more bit, but 7 more are required (for the expansion
factor MAXBSIZE / DEV_BSIZE = 2**7).  More if someone increases MAXBSIZE.

Bruce