From: Christoph Hellwig <hch@lst.de>
To: Jason Gunthorpe <jgg@ziepe.ca>
Cc: "Ralph Campbell" <rcampbell@nvidia.com>,
"Christoph Hellwig" <hch@lst.de>,
"Dan Williams" <dan.j.williams@intel.com>,
"Bharata B Rao" <bharata@linux.ibm.com>,
"Christian König" <christian.koenig@amd.com>,
"Ben Skeggs" <bskeggs@redhat.com>,
"Jerome Glisse" <jglisse@redhat.com>,
kvm-ppc@vger.kernel.org, amd-gfx@lists.freedesktop.org,
dri-devel@lists.freedesktop.org, nouveau@lists.freedesktop.org,
linux-mm@kvack.org
Subject: Re: [PATCH 3/4] mm: simplify device private page handling in hmm_range_fault
Date: Tue, 17 Mar 2020 13:24:45 +0100 [thread overview]
Message-ID: <20200317122445.GA11662@lst.de> (raw)
In-Reply-To: <20200317121536.GQ20941@ziepe.ca>
On Tue, Mar 17, 2020 at 09:15:36AM -0300, Jason Gunthorpe wrote:
> > Getting rid of HMM_PFN_DEVICE_PRIVATE seems reasonable to me since a driver can
> > look at the struct page but what if a driver needs to fault in a page from
> > another device's private memory? Should it call handle_mm_fault()?
>
> Isn't that what this series basically does?
>
> The dev_private_owner is set to the type of pgmap the device knows how
> to handle, and everything else is automatically faulted for the
> device.
>
> If the device does not know how to handle device_private then it sets
> dev_private_owner to NULL and it never gets device_private pfns.
>
> Since the device_private pfn cannot be dma mapped, drivers must have
> explicit support for them.
No, with this series (and all actual callers before this series)
we never fault in device private pages.
next prev parent reply other threads:[~2020-03-17 12:24 UTC|newest]
Thread overview: 38+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-03-16 19:32 ensure device private pages have an owner v2 Christoph Hellwig
2020-03-16 19:32 ` [PATCH 1/4] memremap: add an owner field to struct dev_pagemap Christoph Hellwig
2020-03-16 20:55 ` Ralph Campbell
2020-03-16 19:32 ` [PATCH 2/4] mm: handle multiple owners of device private pages in migrate_vma Christoph Hellwig
2020-03-16 21:43 ` Ralph Campbell
2020-03-16 19:32 ` [PATCH 3/4] mm: simplify device private page handling in hmm_range_fault Christoph Hellwig
2020-03-16 19:59 ` Jason Gunthorpe
2020-03-16 21:33 ` Christoph Hellwig
2020-03-16 22:49 ` Ralph Campbell
2020-03-17 7:34 ` Christoph Hellwig
2020-03-17 22:43 ` Ralph Campbell
2020-03-18 9:34 ` Christoph Hellwig
2020-03-17 12:15 ` Jason Gunthorpe
2020-03-17 12:24 ` Christoph Hellwig [this message]
2020-03-17 12:28 ` Christoph Hellwig
2020-03-17 12:47 ` Jason Gunthorpe
2020-03-17 12:59 ` Christoph Hellwig
2020-03-17 17:32 ` Jason Gunthorpe
2020-03-17 23:14 ` Ralph Campbell
2020-03-19 18:17 ` Jason Gunthorpe
2020-03-19 22:56 ` Ralph Campbell
2020-03-20 0:03 ` Jason Gunthorpe
2020-03-21 8:20 ` Christoph Hellwig
2020-03-20 0:14 ` Jason Gunthorpe
2020-03-20 1:33 ` Ralph Campbell
2020-03-20 12:58 ` Jason Gunthorpe
2020-03-16 19:32 ` [PATCH 4/4] mm: check the device private page owner " Christoph Hellwig
2020-03-16 19:49 ` Jason Gunthorpe
2020-03-16 23:11 ` Ralph Campbell
2020-03-20 13:41 ` Jason Gunthorpe
2020-03-21 8:22 ` Christoph Hellwig
2020-03-21 12:38 ` Jason Gunthorpe
2020-03-21 15:18 ` Christoph Hellwig
2020-03-17 5:31 ` ensure device private pages have an owner v2 Bharata B Rao
2020-03-19 0:28 ` Jason Gunthorpe
2020-03-19 7:16 ` Christoph Hellwig
2020-03-19 11:50 ` Jason Gunthorpe
2020-03-19 18:50 ` Jason Gunthorpe
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20200317122445.GA11662@lst.de \
--to=hch@lst.de \
--cc=amd-gfx@lists.freedesktop.org \
--cc=bharata@linux.ibm.com \
--cc=bskeggs@redhat.com \
--cc=christian.koenig@amd.com \
--cc=dan.j.williams@intel.com \
--cc=dri-devel@lists.freedesktop.org \
--cc=jgg@ziepe.ca \
--cc=jglisse@redhat.com \
--cc=kvm-ppc@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=nouveau@lists.freedesktop.org \
--cc=rcampbell@nvidia.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).