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From:   David Laight <David.Laight@ACULAB.COM>
To:     'Christoph Hellwig' <hch@lst.de>,
        Thomas Bogendoerfer <tsbogend@alpha.franken.de>
CC:     "linux-mips@vger.kernel.org" <linux-mips@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: RE: [PATCH 2/3] MIPS: uaccess: Remove get_fs/set_fs call sites
Thread-Topic: [PATCH 2/3] MIPS: uaccess: Remove get_fs/set_fs call sites
Thread-Index: AQHXJY0yDUIm9QRgRkmPSPWPs+HsZKqdFp4Q
Date:   Tue, 30 Mar 2021 22:10:13 +0000
Message-ID: <5d1aa493b9e7441194677855de560544@AcuMS.aculab.com>
References: <20210330172702.146909-1-tsbogend@alpha.franken.de>
 <20210330172702.146909-3-tsbogend@alpha.franken.de>
 <20210330174943.GB15145@lst.de>
In-Reply-To: <20210330174943.GB15145@lst.de>
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From: Christoph Hellwig
> Sent: 30 March 2021 18:50
> 
> On Tue, Mar 30, 2021 at 07:26:59PM +0200, Thomas Bogendoerfer wrote:
> > +#define __get_data(x, ptr, u)						\
> > +	(((u) == true) ? __get_udata((x), (ptr), sizeof(*(ptr))) :	\
> > +			__get_kdata((x), (ptr), sizeof(*(ptr))))
> > +
> 
> I'm a little worried about exposing this in uaccess.h.  Can you
> have local helpers insted, preferably strongly typed for their
> specific use cases?

For things that aren't performance critical it may be worth
using a structure that contains both a kernel and user address
(one of which will be NULL) and passing the offset as a separate
parameter.

(That might have been better for the socket option buffer.)

	David

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