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Subject: Re: [PATCH 2/2] swiotlb-xen: override common mmap and get_sgtable dma
 ops
To:     Christoph Hellwig <hch@lst.de>
Cc:     Roman Skakun <rm.skakun@gmail.com>,
        Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>,
        Juergen Gross <jgross@suse.com>,
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        Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>,
        Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>,
        Volodymyr Babchuk <volodymyr_babchuk@epam.com>,
        Roman Skakun <roman_skakun@epam.com>,
        Andrii Anisov <andrii_anisov@epam.com>
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From:   Boris Ostrovsky <boris.ostrovsky@oracle.com>
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Date:   Wed, 16 Jun 2021 11:39:07 -0400
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On 6/16/21 11:35 AM, Christoph Hellwig wrote:
> On Wed, Jun 16, 2021 at 11:33:50AM -0400, Boris Ostrovsky wrote:
>> Isn't the expectation of virt_to_page() that it only works on non-vmalloc'd addresses? (This is not a rhetorical question, I actually don't know).
> Yes.  Thus is why I'd suggest to just do the vmalloc_to_page or
> virt_to_page dance in ops_helpers.c and just continue using that.


Ah, OK, so something along the lines of what I suggested. (I thought by "helpers" you meant virt_to_page()).


-boris