Re: [patch 3/3] mm: fault handler to replace nopage and populate

Nick Piggin
2006-10-15T07:54:53Z

Hi Ingo,

Ingo Oeser wrote:
> Hi Nick,
>
> On Thursday, 12. October 2006 14:07, Nick Piggin wrote:
>
>>Actually, filemap_xip needs some attention I think... if xip files
>>can be truncated or invalidated (I assume they can), then we need to
>>lock the page, validate that it is the correct one and not truncated,
>>and return with it locked.
>
>
> ???
>
> Isn't XIP for "eXecuting In Place" from ROM or FLASH?

Yes, I assume so. It seems that it isn't restricted to executing, but
is basically a terminology to mean that it bypasses the pagecache.

> How to truncate these? I thought the whole idea of
> XIP was a pure RO mapping?

Well, not filemap_xip.

>
> They should be valid from mount to umount.
>
> Regards
>
> Ingo Oeser, a bit puzzled about that...

See mm/filemap_xip.c:xip_file_write, xip_truncate_page.

Thanks,
Nick

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SUSE Labs, Novell Inc.
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