[PATCH v4 0/8] mm: Rework hmm to use devm_memremap_pages and other fixes

From: Dan Williams <dan.j.williams@intel.com>
To: akpm@linux-foundation.org
Cc: stable@vger.kernel.org, "Logan Gunthorpe" <logang@deltatee.com>,
	"Christoph Hellwig" <hch@lst.de>,
	"Jérôme Glisse" <jglisse@redhat.com>,
	"Michal Hocko" <mhocko@suse.com>,
	"John Hubbard" <jhubbard@nvidia.com>,
	"Joe Gorse" <jhgorse@gmail.com>,
	linux-mm@kvack.org, linux-kernel@vger.kernel.org
Subject: [PATCH v4 0/8] mm: Rework hmm to use devm_memremap_pages and other fixes
Date: Tue, 10 Jul 2018 22:14:37 -0700	[thread overview]
Message-ID: <153128607743.2928.4465435789810433432.stgit@dwillia2-desk3.amr.corp.intel.com> (raw)

Changes since v3 [1]:
* Collect Logan's reviewed-by on patch 3
* Collect John's and Joe's tested-by on patch 8
* Update the changelog for patch 1 and 7 to better explain the
  EXPORT_SYMBOL_GPL rationale.
* Update the changelog for patch 2 to clarify that it is a cleanup to
  make the following patch-3 fix easier

[1]: https://lkml.org/lkml/2018/6/19/108

---

Hi Andrew,

As requested, here is a resend of the devm_memremap_pages() fixups.
Please consider for 4.18.

---

As ZONE_DEVICE continues to attract new users, it is imperative to keep
all users consolidated on devm_memremap_pages() as the interface for
create "device pages".

The devm_memremap_pages() implementation was recently reworked to make
it more generic for arbitrary users, like the proposed peer-to-peer
PCI-E enabling. HMM pre-dated this rework and opted to duplicate
devm_memremap_pages() as hmm_devmem_pages_create().

Rework hmm to be a consumer of devm_memremap_pages() directly and fix up
the licensing on the exports given the deep dependencies and exposure of
core mm internals.

With the exports of devm_memremap_pages() and hmm fixed up we can fix
the regression of inadvertently making put_page() have EXPORT_SYMBOL_GPL
dependencies, which breaks consumers like OpenAFS.

The series was tested against v4.18-rc2.

---

Dan Williams (8):
      mm, devm_memremap_pages: Mark devm_memremap_pages() EXPORT_SYMBOL_GPL
      mm, devm_memremap_pages: Kill mapping "System RAM" support
      mm, devm_memremap_pages: Fix shutdown handling
      mm, devm_memremap_pages: Add MEMORY_DEVICE_PRIVATE support
      mm, hmm: Use devm semantics for hmm_devmem_{add,remove}
      mm, hmm: Replace hmm_devmem_pages_create() with devm_memremap_pages()
      mm, hmm: Mark hmm_devmem_{add,add_resource} EXPORT_SYMBOL_GPL
      mm: Fix exports that inadvertently make put_page() EXPORT_SYMBOL_GPL

 drivers/dax/pmem.c                |   10 -
 drivers/nvdimm/pmem.c             |   18 +-
 include/linux/hmm.h               |    4 
 include/linux/memremap.h          |    7 +
 kernel/memremap.c                 |   89 +++++++----
 mm/hmm.c                          |  306 +++++--------------------------------
 tools/testing/nvdimm/test/iomap.c |   21 ++-
 7 files changed, 132 insertions(+), 323 deletions(-)