Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
From:   John Hubbard <jhubbard@nvidia.com>
To:     Andrew Morton <akpm@linux-foundation.org>
CC:     Souptick Joarder <jrdr.linux@gmail.com>,
        Matthew Wilcox <willy@infradead.org>,
        Jani Nikula <jani.nikula@linux.intel.com>,
        Joonas Lahtinen <joonas.lahtinen@linux.intel.com>,
        Rodrigo Vivi <rodrigo.vivi@intel.com>,
        David Airlie <airlied@linux.ie>,
        Daniel Vetter <daniel@ffwll.ch>,
        Chris Wilson <chris@chris-wilson.co.uk>,
        Tvrtko Ursulin <tvrtko.ursulin@intel.com>,
        Matthew Auld <matthew.auld@intel.com>,
        <intel-gfx@lists.freedesktop.org>,
        <dri-devel@lists.freedesktop.org>,
        LKML <linux-kernel@vger.kernel.org>, <linux-mm@kvack.org>,
        John Hubbard <jhubbard@nvidia.com>
Subject: [PATCH v2 0/4] mm/gup, drm/i915: refactor gup_fast, convert to pin_user_pages()
Date:   Thu, 21 May 2020 22:19:27 -0700
Message-ID: <20200522051931.54191-1-jhubbard@nvidia.com>
MIME-Version: 1.0
Content-Transfer-Encoding: quoted-printable
Content-Type: text/plain
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

The purpose of posting this series is to launch a test in the
intel-gfx-ci tree. (The patches have already been merged into Andrew's
linux-mm tree.)

This applies to today's linux.git (note the base-commit tag at the
bottom).

Changes since V1:

* Fixed a bug in the refactoring patch: added FOLL_FAST_ONLY to the
  list of gup_flags *not* to WARN() on. This lead to a failure in the
  first intel-gfx-ci test run [1].

[1] https://lore.kernel.org/r/159008745422.32320.5724805750977048669@build.=
alporthouse.com

Original cover letter:

This needs to go through Andrew's -mm tree, due to adding a new gup.c
routine. However, I would really love to have some testing from the
drm/i915 folks, because I haven't been able to run-time test that part
of it.

Otherwise, though, the series has passed my basic run time testing:
some LTP tests, some xfs and etx4 non-destructive xfstests, and an
assortment of other smaller ones: vm selftests, io_uring_register, a
few more. But that's only on one particular machine. Also, cross-compile
tests for half a dozen arches all pass.

Details:

In order to convert the drm/i915 driver from get_user_pages() to
pin_user_pages(), a FOLL_PIN equivalent of __get_user_pages_fast() was
required. That led to refactoring __get_user_pages_fast(), with the
following goals:

1) As above: provide a pin_user_pages*() routine for drm/i915 to call,
   in place of __get_user_pages_fast(),

2) Get rid of the gup.c duplicate code for walking page tables with
   interrupts disabled. This duplicate code is a minor maintenance
   problem anyway.

3) Make it easy for an upcoming patch from Souptick, which aims to
   convert __get_user_pages_fast() to use a gup_flags argument, instead
   of a bool writeable arg.  Also, if this series looks good, we can
   ask Souptick to change the name as well, to whatever the consensus
   is. My initial recommendation is: get_user_pages_fast_only(), to
   match the new pin_user_pages_only().

John Hubbard (4):
  mm/gup: move __get_user_pages_fast() down a few lines in gup.c
  mm/gup: refactor and de-duplicate gup_fast() code
  mm/gup: introduce pin_user_pages_fast_only()
  drm/i915: convert get_user_pages() --> pin_user_pages()

 drivers/gpu/drm/i915/gem/i915_gem_userptr.c |  22 +--
 include/linux/mm.h                          |   3 +
 mm/gup.c                                    | 153 ++++++++++++--------
 3 files changed, 109 insertions(+), 69 deletions(-)


base-commit: 051143e1602d90ea71887d92363edd539d411de5
--=20
2.26.2