Re: [RFC PATCH 00/22] Enhance VHOST to enable SoC-to-SoC communication

From: Kishon Vijay Abraham I
Date: Fri Jul 03 2020 - 02:18:21 EST


+Alan, Haotian

On 7/2/2020 11:01 PM, Mathieu Poirier wrote:
> On Thu, 2 Jul 2020 at 03:51, Michael S. Tsirkin <mst@xxxxxxxxxx> wrote:
>>
>> On Thu, Jul 02, 2020 at 01:51:21PM +0530, Kishon Vijay Abraham I wrote:
>>> This series enhances Linux Vhost support to enable SoC-to-SoC
>>> communication over MMIO. This series enables rpmsg communication between
>>> two SoCs using both PCIe RC<->EP and HOST1-NTB-HOST2
>>>
>>> 1) Modify vhost to use standard Linux driver model
>>> 2) Add support in vring to access virtqueue over MMIO
>>> 3) Add vhost client driver for rpmsg
>>> 4) Add PCIe RC driver (uses virtio) and PCIe EP driver (uses vhost) for
>>> rpmsg communication between two SoCs connected to each other
>>> 5) Add NTB Virtio driver and NTB Vhost driver for rpmsg communication
>>> between two SoCs connected via NTB
>>> 6) Add configfs to configure the components
>>>
>>> UseCase1 :
>>>
>>> VHOST RPMSG VIRTIO RPMSG
>>> + +
>>> | |
>>> | |
>>> | |
>>> | |
>>> +-----v------+ +------v-------+
>>> | Linux | | Linux |
>>> | Endpoint | | Root Complex |
>>> | <-----------------> |
>>> | | | |
>>> | SOC1 | | SOC2 |
>>> +------------+ +--------------+
>>>
>>> UseCase 2:
>>>
>>> VHOST RPMSG VIRTIO RPMSG
>>> + +
>>> | |
>>> | |
>>> | |
>>> | |
>>> +------v------+ +------v------+
>>> | | | |
>>> | HOST1 | | HOST2 |
>>> | | | |
>>> +------^------+ +------^------+
>>> | |
>>> | |
>>> +---------------------------------------------------------------------+
>>> | +------v------+ +------v------+ |
>>> | | | | | |
>>> | | EP | | EP | |
>>> | | CONTROLLER1 | | CONTROLLER2 | |
>>> | | <-----------------------------------> | |
>>> | | | | | |
>>> | | | | | |
>>> | | | SoC With Multiple EP Instances | | |
>>> | | | (Configured using NTB Function) | | |
>>> | +-------------+ +-------------+ |
>>> +---------------------------------------------------------------------+
>>>
>>> Software Layering:
>>>
>>> The high-level SW layering should look something like below. This series
>>> adds support only for RPMSG VHOST, however something similar should be
>>> done for net and scsi. With that any vhost device (PCI, NTB, Platform
>>> device, user) can use any of the vhost client driver.
>>>
>>>
>>> +----------------+ +-----------+ +------------+ +----------+
>>> | RPMSG VHOST | | NET VHOST | | SCSI VHOST | | X |
>>> +-------^--------+ +-----^-----+ +-----^------+ +----^-----+
>>> | | | |
>>> | | | |
>>> | | | |
>>> +-----------v-----------------v--------------v--------------v----------+
>>> | VHOST CORE |
>>> +--------^---------------^--------------------^------------------^-----+
>>> | | | |
>>> | | | |
>>> | | | |
>>> +--------v-------+ +----v------+ +----------v----------+ +----v-----+
>>> | PCI EPF VHOST | | NTB VHOST | |PLATFORM DEVICE VHOST| | X |
>>> +----------------+ +-----------+ +---------------------+ +----------+
>>>
>>> This was initially proposed here [1]
>>>
>>> [1] -> https://lore.kernel.org/r/2cf00ec4-1ed6-f66e-6897-006d1a5b6390@xxxxxx
>>
>>
>> I find this very interesting. A huge patchset so will take a bit
>> to review, but I certainly plan to do that. Thanks!
>
> Same here - it will take time. This patchset is sizable and sits
> behind a few others that are equally big.
>
>>
>>>
>>> Kishon Vijay Abraham I (22):
>>> vhost: Make _feature_ bits a property of vhost device
>>> vhost: Introduce standard Linux driver model in VHOST
>>> vhost: Add ops for the VHOST driver to configure VHOST device
>>> vringh: Add helpers to access vring in MMIO
>>> vhost: Add MMIO helpers for operations on vhost virtqueue
>>> vhost: Introduce configfs entry for configuring VHOST
>>> virtio_pci: Use request_threaded_irq() instead of request_irq()
>>> rpmsg: virtio_rpmsg_bus: Disable receive virtqueue callback when
>>> reading messages
>>> rpmsg: Introduce configfs entry for configuring rpmsg
>>> rpmsg: virtio_rpmsg_bus: Add Address Service Notification support
>>> rpmsg: virtio_rpmsg_bus: Move generic rpmsg structure to
>>> rpmsg_internal.h
>>> virtio: Add ops to allocate and free buffer
>>> rpmsg: virtio_rpmsg_bus: Use virtio_alloc_buffer() and
>>> virtio_free_buffer()
>>> rpmsg: Add VHOST based remote processor messaging bus
>>> samples/rpmsg: Setup delayed work to send message
>>> samples/rpmsg: Wait for address to be bound to rpdev for sending
>>> message
>>> rpmsg.txt: Add Documentation to configure rpmsg using configfs
>>> virtio_pci: Add VIRTIO driver for VHOST on Configurable PCIe Endpoint
>>> device
>>> PCI: endpoint: Add EP function driver to provide VHOST interface
>>> NTB: Add a new NTB client driver to implement VIRTIO functionality
>>> NTB: Add a new NTB client driver to implement VHOST functionality
>>> NTB: Describe the ntb_virtio and ntb_vhost client in the documentation
>>>
>>> Documentation/driver-api/ntb.rst | 11 +
>>> Documentation/rpmsg.txt | 56 +
>>> drivers/ntb/Kconfig | 18 +
>>> drivers/ntb/Makefile | 2 +
>>> drivers/ntb/ntb_vhost.c | 776 +++++++++++
>>> drivers/ntb/ntb_virtio.c | 853 ++++++++++++
>>> drivers/ntb/ntb_virtio.h | 56 +
>>> drivers/pci/endpoint/functions/Kconfig | 11 +
>>> drivers/pci/endpoint/functions/Makefile | 1 +
>>> .../pci/endpoint/functions/pci-epf-vhost.c | 1144 ++++++++++++++++
>>> drivers/rpmsg/Kconfig | 10 +
>>> drivers/rpmsg/Makefile | 3 +-
>>> drivers/rpmsg/rpmsg_cfs.c | 394 ++++++
>>> drivers/rpmsg/rpmsg_core.c | 7 +
>>> drivers/rpmsg/rpmsg_internal.h | 136 ++
>>> drivers/rpmsg/vhost_rpmsg_bus.c | 1151 +++++++++++++++++
>>> drivers/rpmsg/virtio_rpmsg_bus.c | 184 ++-
>>> drivers/vhost/Kconfig | 1 +
>>> drivers/vhost/Makefile | 2 +-
>>> drivers/vhost/net.c | 10 +-
>>> drivers/vhost/scsi.c | 24 +-
>>> drivers/vhost/test.c | 17 +-
>>> drivers/vhost/vdpa.c | 2 +-
>>> drivers/vhost/vhost.c | 730 ++++++++++-
>>> drivers/vhost/vhost_cfs.c | 341 +++++
>>> drivers/vhost/vringh.c | 332 +++++
>>> drivers/vhost/vsock.c | 20 +-
>>> drivers/virtio/Kconfig | 9 +
>>> drivers/virtio/Makefile | 1 +
>>> drivers/virtio/virtio_pci_common.c | 25 +-
>>> drivers/virtio/virtio_pci_epf.c | 670 ++++++++++
>>> include/linux/mod_devicetable.h | 6 +
>>> include/linux/rpmsg.h | 6 +
>>> {drivers/vhost => include/linux}/vhost.h | 132 +-
>>> include/linux/virtio.h | 3 +
>>> include/linux/virtio_config.h | 42 +
>>> include/linux/vringh.h | 46 +
>>> samples/rpmsg/rpmsg_client_sample.c | 32 +-
>>> tools/virtio/virtio_test.c | 2 +-
>>> 39 files changed, 7083 insertions(+), 183 deletions(-)
>>> create mode 100644 drivers/ntb/ntb_vhost.c
>>> create mode 100644 drivers/ntb/ntb_virtio.c
>>> create mode 100644 drivers/ntb/ntb_virtio.h
>>> create mode 100644 drivers/pci/endpoint/functions/pci-epf-vhost.c
>>> create mode 100644 drivers/rpmsg/rpmsg_cfs.c
>>> create mode 100644 drivers/rpmsg/vhost_rpmsg_bus.c
>>> create mode 100644 drivers/vhost/vhost_cfs.c
>>> create mode 100644 drivers/virtio/virtio_pci_epf.c
>>> rename {drivers/vhost => include/linux}/vhost.h (66%)
>>>
>>> --
>>> 2.17.1
>>>
>>