[RFC PATCH v2 0/9] hyper_dmabuf: Hyper_DMABUF driver

[Dongwon Kim]

This patch series contains the implementation of a new device driver,
hyper_DMABUF driver, which provides a way to expand the boundary of
Linux DMA-BUF sharing to across different VM instances in Multi-OS platform
enabled by a Hypervisor (e.g. XEN)

This version 2 series is basically refactored version of old series starting
with "[RFC PATCH 01/60] hyper_dmabuf: initial working version of hyper_dmabuf
drv"

Implementation details of this driver are described in the reference guide
added by the second patch, "[RFC PATCH v2 2/5] hyper_dmabuf: architecture
specification and reference guide".

Attaching 'Overview' section here as a quick summary.

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Section 1. Overview
------------------------------------------------------------------------------

Hyper_DMABUF driver is a Linux device driver running on multiple Virtual
achines (VMs), which expands DMA-BUF sharing capability to the VM environment
where multiple different OS instances need to share same physical data without
data-copy across VMs.

To share a DMA_BUF across VMs, an instance of the Hyper_DMABUF drv on the
exporting VM (so called, âexporterâ) imports a local DMA_BUF from the original
producer of the buffer, then re-exports it with an unique ID, hyper_dmabuf_id
for the buffer to the importing VM (so called, âimporterâ).

Another instance of the Hyper_DMABUF driver on importer registers
a hyper_dmabuf_id together with reference information for the shared physical
pages associated with the DMA_BUF to its database when the export happens.

The actual mapping of the DMA_BUF on the importerâs side is done by
the Hyper_DMABUF driver when user space issues the IOCTL command to access
the shared DMA_BUF. The Hyper_DMABUF driver works as both an importing and
exporting driver as is, that is, no special configuration is required.
Consequently, only a single module per VM is needed to enable cross-VM DMA_BUF
exchange.

------------------------------------------------------------------------------

There is a git repository at github.com where this series of patches are all
integrated in Linux kernel tree based on the commit:

        commit ae64f9bd1d3621b5e60d7363bc20afb46aede215
        Author: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
        Date:   Sun Dec 3 11:01:47 2018 -0500

            Linux 4.15-rc2

https://github.com/downor/linux_hyper_dmabuf.git hyper_dmabuf_integration_v4

Dongwon Kim, Mateusz Polrola (9):
  hyper_dmabuf: initial upload of hyper_dmabuf drv core framework
  hyper_dmabuf: architecture specification and reference guide
  MAINTAINERS: adding Hyper_DMABUF driver section in MAINTAINERS
  hyper_dmabuf: user private data attached to hyper_DMABUF
  hyper_dmabuf: hyper_DMABUF synchronization across VM
  hyper_dmabuf: query ioctl for retreiving various hyper_DMABUF info
  hyper_dmabuf: event-polling mechanism for detecting a new hyper_DMABUF
  hyper_dmabuf: threaded interrupt in Xen-backend
  hyper_dmabuf: default backend for XEN hypervisor

 Documentation/hyper-dmabuf-sharing.txt             | 734 ++++++++++++++++
 MAINTAINERS                                        |  11 +
 drivers/dma-buf/Kconfig                            |   2 +
 drivers/dma-buf/Makefile                           |   1 +
 drivers/dma-buf/hyper_dmabuf/Kconfig               |  50 ++
 drivers/dma-buf/hyper_dmabuf/Makefile              |  44 +
 .../backends/xen/hyper_dmabuf_xen_comm.c           | 944 +++++++++++++++++++++
 .../backends/xen/hyper_dmabuf_xen_comm.h           |  78 ++
 .../backends/xen/hyper_dmabuf_xen_comm_list.c      | 158 ++++
 .../backends/xen/hyper_dmabuf_xen_comm_list.h      |  67 ++
 .../backends/xen/hyper_dmabuf_xen_drv.c            |  46 +
 .../backends/xen/hyper_dmabuf_xen_drv.h            |  53 ++
 .../backends/xen/hyper_dmabuf_xen_shm.c            | 525 ++++++++++++
 .../backends/xen/hyper_dmabuf_xen_shm.h            |  46 +
 drivers/dma-buf/hyper_dmabuf/hyper_dmabuf_drv.c    | 410 +++++++++
 drivers/dma-buf/hyper_dmabuf/hyper_dmabuf_drv.h    | 122 +++
 drivers/dma-buf/hyper_dmabuf/hyper_dmabuf_event.c  | 122 +++
 drivers/dma-buf/hyper_dmabuf/hyper_dmabuf_event.h  |  38 +
 drivers/dma-buf/hyper_dmabuf/hyper_dmabuf_id.c     | 135 +++
 drivers/dma-buf/hyper_dmabuf/hyper_dmabuf_id.h     |  53 ++
 drivers/dma-buf/hyper_dmabuf/hyper_dmabuf_ioctl.c  | 794 +++++++++++++++++
 drivers/dma-buf/hyper_dmabuf/hyper_dmabuf_ioctl.h  |  52 ++
 drivers/dma-buf/hyper_dmabuf/hyper_dmabuf_list.c   | 295 +++++++
 drivers/dma-buf/hyper_dmabuf/hyper_dmabuf_list.h   |  73 ++
 drivers/dma-buf/hyper_dmabuf/hyper_dmabuf_msg.c    | 416 +++++++++
 drivers/dma-buf/hyper_dmabuf/hyper_dmabuf_msg.h    |  89 ++
 drivers/dma-buf/hyper_dmabuf/hyper_dmabuf_ops.c    | 415 +++++++++
 drivers/dma-buf/hyper_dmabuf/hyper_dmabuf_ops.h    |  34 +
 drivers/dma-buf/hyper_dmabuf/hyper_dmabuf_query.c  | 174 ++++
 drivers/dma-buf/hyper_dmabuf/hyper_dmabuf_query.h  |  36 +
 .../hyper_dmabuf/hyper_dmabuf_remote_sync.c        | 324 +++++++
 .../hyper_dmabuf/hyper_dmabuf_remote_sync.h        |  32 +
 .../dma-buf/hyper_dmabuf/hyper_dmabuf_sgl_proc.c   | 257 ++++++
 .../dma-buf/hyper_dmabuf/hyper_dmabuf_sgl_proc.h   |  43 +
 drivers/dma-buf/hyper_dmabuf/hyper_dmabuf_struct.h | 143 ++++
 include/uapi/linux/hyper_dmabuf.h                  | 134 +++
 36 files changed, 6950 insertions(+)
 create mode 100644 Documentation/hyper-dmabuf-sharing.txt
 create mode 100644 drivers/dma-buf/hyper_dmabuf/Kconfig
 create mode 100644 drivers/dma-buf/hyper_dmabuf/Makefile
 create mode 100644 drivers/dma-buf/hyper_dmabuf/backends/xen/hyper_dmabuf_xen_comm.c
 create mode 100644 drivers/dma-buf/hyper_dmabuf/backends/xen/hyper_dmabuf_xen_comm.h
 create mode 100644 drivers/dma-buf/hyper_dmabuf/backends/xen/hyper_dmabuf_xen_comm_list.c
 create mode 100644 drivers/dma-buf/hyper_dmabuf/backends/xen/hyper_dmabuf_xen_comm_list.h
 create mode 100644 drivers/dma-buf/hyper_dmabuf/backends/xen/hyper_dmabuf_xen_drv.c
 create mode 100644 drivers/dma-buf/hyper_dmabuf/backends/xen/hyper_dmabuf_xen_drv.h
 create mode 100644 drivers/dma-buf/hyper_dmabuf/backends/xen/hyper_dmabuf_xen_shm.c
 create mode 100644 drivers/dma-buf/hyper_dmabuf/backends/xen/hyper_dmabuf_xen_shm.h
 create mode 100644 drivers/dma-buf/hyper_dmabuf/hyper_dmabuf_drv.c
 create mode 100644 drivers/dma-buf/hyper_dmabuf/hyper_dmabuf_drv.h
 create mode 100644 drivers/dma-buf/hyper_dmabuf/hyper_dmabuf_event.c
 create mode 100644 drivers/dma-buf/hyper_dmabuf/hyper_dmabuf_event.h
 create mode 100644 drivers/dma-buf/hyper_dmabuf/hyper_dmabuf_id.c
 create mode 100644 drivers/dma-buf/hyper_dmabuf/hyper_dmabuf_id.h
 create mode 100644 drivers/dma-buf/hyper_dmabuf/hyper_dmabuf_ioctl.c
 create mode 100644 drivers/dma-buf/hyper_dmabuf/hyper_dmabuf_ioctl.h
 create mode 100644 drivers/dma-buf/hyper_dmabuf/hyper_dmabuf_list.c
 create mode 100644 drivers/dma-buf/hyper_dmabuf/hyper_dmabuf_list.h
 create mode 100644 drivers/dma-buf/hyper_dmabuf/hyper_dmabuf_msg.c
 create mode 100644 drivers/dma-buf/hyper_dmabuf/hyper_dmabuf_msg.h
 create mode 100644 drivers/dma-buf/hyper_dmabuf/hyper_dmabuf_ops.c
 create mode 100644 drivers/dma-buf/hyper_dmabuf/hyper_dmabuf_ops.h
 create mode 100644 drivers/dma-buf/hyper_dmabuf/hyper_dmabuf_query.c
 create mode 100644 drivers/dma-buf/hyper_dmabuf/hyper_dmabuf_query.h
 create mode 100644 drivers/dma-buf/hyper_dmabuf/hyper_dmabuf_remote_sync.c
 create mode 100644 drivers/dma-buf/hyper_dmabuf/hyper_dmabuf_remote_sync.h
 create mode 100644 drivers/dma-buf/hyper_dmabuf/hyper_dmabuf_sgl_proc.c
 create mode 100644 drivers/dma-buf/hyper_dmabuf/hyper_dmabuf_sgl_proc.h
 create mode 100644 drivers/dma-buf/hyper_dmabuf/hyper_dmabuf_struct.h
 create mode 100644 include/uapi/linux/hyper_dmabuf.h

-- 
2.16.1