Re: [PATCH] [RFC] LBD fixes for Linux 2.6.10 [2/2]

[Matthew Wilcox <matthew@wil.cx>]

On Tue, Jan 11, 2005 at 01:47:53PM -0500, Tony Battersby wrote:
> Here is an "example" patch to fix some of the LBD issues with various
> filesystems (ext3, reiserfs, xfs).  Unfortunately it looks like there
> are many more LBD problems with the filesystems that I didn't fix, so I
> am just calling this an "example" patch that shows some of what needs
> to be done, but doesn't fix everything.  I am not a filesystem expert,
> so I would prefer to leave it to others to do a full audit of all the
> filesystems for LBD-compliance.  Specifically there are two things to
> check:
> 
> 1) Use sector_t rather than long or unsigned long for block numbers.
> For auditing, just search for all occurrences of "long" in the filesystem
> code and make sure it is not referring to a block number.

That's actually not wise.  For ext3, the block numbers _on disc_
are 32-bit in size, so making them sector_t in memory is just a waste.
reiserfs seems to be the same.  OTOH, XFS does use 64-bit blocks on disc,
so should use an explicitly 64-bit size in memory too.

-- 
"Next the statesmen will invent cheap lies, putting the blame upon 
the nation that is attacked, and every man will be glad of those
conscience-soothing falsities, and will diligently study them, and refuse
to examine any refutations of them; and thus he will by and by convince 
himself that the war is just, and will thank God for the better sleep 
he enjoys after this process of grotesque self-deception." -- Mark Twain