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Date:   Wed, 24 Jun 2020 19:55:48 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     Linus Torvalds <torvalds@linux-foundation.org>
Cc:     Christoph Hellwig <hch@lst.de>, Al Viro <viro@zeniv.linux.org.uk>,
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Subject: Re: [PATCH 03/11] fs: add new read_uptr and write_uptr file
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On Wed, Jun 24, 2020 at 10:19:16AM -0700, Linus Torvalds wrote:
> Honestly, I think this is the wrong way to go.
> 
> All of this new complexity and messiness, just to remove a few
> unimportant final cases?
> 
> If somebody can't be bothered to convert a driver to
> iter_read/iter_write, why would they be bothered to convert it to
> read_uptr/write_uptr?
> 
> And this messiness will stay around for decades.
> 
> So let's not go down that path.
> 
> If you want to do "splice() and kernel_read() requires read_iter"
> (with a warning so that we find any cases), then that's fine. But
> let's not add yet _another_ read type.
> 
> Why did you care so much about sysctl, and why couldn't they use the iter ops?

I don't care at all.  Based on our previous chat I assumed you
wanted something like this.  We might still need the uptr_t for
setsockopt, though.