Re: [PATCH] UBIFS: endian handling fixes and annotations

From: Artem Bityutskiy <dedekind@infradead.org>
To: Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] UBIFS: endian handling fixes and annotations
Date: Tue, 02 Dec 2008 11:12:35 +0200	[thread overview]
Message-ID: <1228209155.5029.30.camel@sauron> (raw)
In-Reply-To: <20081122192747.GB21433@Chamillionaire.breakpoint.cc>

On Sat, 2008-11-22 at 20:27 +0100, Sebastian Andrzej Siewior wrote:
> >index 9ee6508..3f1f16b 100644
> >--- a/fs/ubifs/key.h
> >+++ b/fs/ubifs/key.h
> >@@ -345,7 +345,7 @@ static inline int key_type_flash(const struct ubifs_info *c, const void *k)
> > {
> > 	const union ubifs_key *key = k;
> > 
> >-	return le32_to_cpu(key->u32[1]) >> UBIFS_S_KEY_BLOCK_BITS;
> >+	return le32_to_cpu(key->j32[1]) >> UBIFS_S_KEY_BLOCK_BITS;
> 
> If you would change such references to something like
> |return le32_to_cpup(&key->j32[1]) >> UBIFS_S_KEY_BLOCK_BITS;
> then on powerpc
> 
>   text    data     bss     dec     hex filename
> 155384    1284      24  156692   26414 ubifs-b4.ko
> 155372    1284      24  156680   26408 ubifs-after.ko
> 
> because now it is possible to load the value as LE from memory instead
> of loading it BE and swapping it afterwads.

Well, I think stuff like this should be done by either GCC or by a PPC-specific
'le32_to_cpu()' implementation.

-- 
Best regards,
Artem Bityutskiy (Битюцкий Артём)