Re: [PATCH 16/17] memremap: change devm_memremap_pages interface to use struct dev_pagemap

From: Christoph Hellwig
Date: Tue Dec 19 2017 - 10:03:53 EST


On Sun, Dec 17, 2017 at 10:51:56AM -0800, Dan Williams wrote:
> On Fri, Dec 15, 2017 at 6:09 AM, Christoph Hellwig <hch@xxxxxx> wrote:
> > From: Logan Gunthorpe <logang@xxxxxxxxxxxx>
> >
> > This new interface is similar to how struct device (and many others)
> > work. The caller initializes a 'struct dev_pagemap' as required
> > and calls 'devm_memremap_pages'. This allows the pagemap structure to
> > be embedded in another structure and thus container_of can be used. In
> > this way application specific members can be stored in a containing
> > struct.
> >
> > This will be used by the P2P infrastructure and HMM could probably
> > be cleaned up to use it as well (instead of having it's own, similar
> > 'hmm_devmem_pages_create' function).
> >
> > Signed-off-by: Logan Gunthorpe <logang@xxxxxxxxxxxx>
> > Signed-off-by: Christoph Hellwig <hch@xxxxxx>
>
> Looks good, I notice that this does not initialize pgmap->type to
> MEMORY_DEVICE_HOST, but since that value is zero and likely won't
> change we're ok.

I'll add it jut for clarity.