Re: [PATCH 1/2] Make cramfs little endian only

[Linus Torvalds <torvalds@linux-foundation.org>]

On Thu, 6 Dec 2007, Jörn Engel wrote:
> 
> How about shifting and masking _before_ converting to host endianness?
> 
> 	static inline u32 cramfs_offset(struct cramfs_inode *inode)
> 	{
> 		return le32_to_cpu(node->namelen_offset >> CRAMFS_NAMELEN_WIDTH);
> 	}

Stop this idiocy. The code I sent out was correct. You're just making it 
worse.

"le32_to_cpu()" is a no-op on little-endian machines. So your change won't 
make any difference there. But the point is, that if we want the disk 
layout to be the *same* for both big-endian and little-endian, we need to 
switch the word as it is loaded from memory, and not do *any* operations 
on it before we've done that equalization.

This is not something unusual. It's bog-standard procedure for a lot of 
filesystems. And sparse will help you (and would have complained about 
your code that tries to shift a little-endian entity before changing it 
into a CPU-endian one).

			Linus
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