From mboxrd@z Thu Jan  1 00:00:00 1970
From: Al Viro <viro@ZenIV.linux.org.uk>
Subject: Re: [RFC][PATCH] new byteorder primitives - ..._{replace,get}_bits()
Date: Wed, 13 Dec 2017 17:45:54 +0000
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Cc: Linus Torvalds <torvalds@linux-foundation.org>,
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To: Jakub Kicinski <kubakici@wp.pl>
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On Wed, Dec 13, 2017 at 02:22:12PM +0000, Al Viro wrote:

> Next question: where do we put that bunch?  I've put it into
> linux/byteorder/generic.h, so that anything picking fixed-endian primitives
> would pick those as well; I hadn't thought of linux/bitfield.h at the time.
> We certainly could put it there instead - it's never pulled by other headers,
> so adding #include <asm/byteorder.h> into linux/bitfield.h is not going to
> cause header order problems.  Not sure...
> 
> Linus, do you have any preferences in that area?

After looking at some of the callers of bitfield.h stuff: it might be useful
to add

static inline void le64p_replace_bits(__le64 *p, u64 v, u64 mask)
{
	__le64 m = cpu_to_le64(mask);
	*p = (*p & ~m) | (cpu_to_le64(v * mask_to_multiplier(mask)) & m);
}

and similar for other types.  Not sure what would be a good name for
host-endian variants - u64p_replace_bits() sounds a bit clumsy.  Suggestions?