Re: [PATCH v3 3/4] net/ifcvf: add ifcvf vdpa driver

["Wang, Xiao W" <xiao.w.wang@intel.com>]

Hi Maxime,

> -----Original Message-----
> From: Maxime Coquelin [mailto:maxime.coquelin@redhat.com]
> Sent: Saturday, March 31, 2018 7:27 PM
> To: Wang, Xiao W <xiao.w.wang@intel.com>; Yigit, Ferruh
> <ferruh.yigit@intel.com>
> Cc: dev@dpdk.org; Wang, Zhihong <zhihong.wang@intel.com>;
> yliu@fridaylinux.org; Tan, Jianfeng <jianfeng.tan@intel.com>; Bie, Tiwei
> <tiwei.bie@intel.com>; Liang, Cunming <cunming.liang@intel.com>; Daly, Dan
> <dan.daly@intel.com>; thomas@monjalon.net; gaetan.rivet@6wind.com;
> Burakov, Anatoly <anatoly.burakov@intel.com>; Xu, Rosen
> <rosen.xu@intel.com>
> Subject: Re: [PATCH v3 3/4] net/ifcvf: add ifcvf vdpa driver
> 
> 
> 
> On 03/31/2018 04:29 AM, Xiao Wang wrote:
> > The IFCVF vDPA (vhost data path acceleration) driver provides support for
> > the Intel FPGA 100G VF (IFCVF). IFCVF's datapath is virtio ring compatible,
> > it works as a HW vhost backend which can send/receive packets to/from
> > virtio directly by DMA.
> >
> > Different VF devices serve different virtio frontends which are in
> > different VMs, so each VF needs to have its own DMA address translation
> > service. During the driver probe a new container is created, with this
> > container vDPA driver can program DMA remapping table with the VM's
> memory
> > region information.
> >
> > Key vDPA driver ops implemented:
> >
> > - ifcvf_dev_config:
> >    Enable VF data path with virtio information provided by vhost lib,
> >    including IOMMU programming to enable VF DMA to VM's memory, VFIO
> >    interrupt setup to route HW interrupt to virtio driver, create notify
> >    relay thread to translate virtio driver's kick to a MMIO write onto HW,
> >    HW queues configuration.
> >
> > - ifcvf_dev_close:
> >    Revoke all the setup in ifcvf_dev_config.
> >
> > Live migration feature is supported by IFCVF and this driver enables
> > it. For the dirty page logging, VF helps to log for packet buffer write,
> > driver helps to make the used ring as dirty when device stops.
> >
> > Because vDPA driver needs to set up MSI-X vector to interrupt the
> > guest, only vfio-pci is supported currently.
> >
> > Signed-off-by: Xiao Wang <xiao.w.wang@intel.com>
> > Signed-off-by: Rosen Xu <rosen.xu@intel.com>
> > ---
> >   config/common_base                    |   7 +
> >   config/common_linuxapp                |   1 +
> >   drivers/net/Makefile                  |   3 +
> >   drivers/net/ifc/Makefile              |  36 ++
> >   drivers/net/ifc/base/ifcvf.c          | 329 +++++++++++++
> >   drivers/net/ifc/base/ifcvf.h          | 160 +++++++
> >   drivers/net/ifc/base/ifcvf_osdep.h    |  52 +++
> >   drivers/net/ifc/ifcvf_vdpa.c          | 842
> ++++++++++++++++++++++++++++++++++
> >   drivers/net/ifc/rte_ifcvf_version.map |   4 +
> >   mk/rte.app.mk                         |   3 +
> >   10 files changed, 1437 insertions(+)
> >   create mode 100644 drivers/net/ifc/Makefile
> >   create mode 100644 drivers/net/ifc/base/ifcvf.c
> >   create mode 100644 drivers/net/ifc/base/ifcvf.h
> >   create mode 100644 drivers/net/ifc/base/ifcvf_osdep.h
> >   create mode 100644 drivers/net/ifc/ifcvf_vdpa.c
> >   create mode 100644 drivers/net/ifc/rte_ifcvf_version.map
> 
> Thanks for having handled the changes, please see minor comments below.
> 
> Feel free to add my:
> Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
> 
> Thanks!
> Maxime
> 
> > +static uint64_t
> > +qva_to_gpa(int vid, uint64_t qva)
> 
> We might want to have this in vhost-lib to avoid duplication,
> but that can be done later.
> 
> > +{
> > +	struct rte_vhost_memory *mem = NULL;
> > +	struct rte_vhost_mem_region *reg;
> > +	uint32_t i;
> > +	uint64_t gpa = 0;
> > +
> > +	if (rte_vhost_get_mem_table(vid, &mem) < 0)
> > +		goto exit;
> > +
> > +	for (i = 0; i < mem->nregions; i++) {

[...]

> > +
> > +struct rte_vdpa_dev_ops ifcvf_ops = {
> > +	.queue_num_get = ifcvf_get_queue_num,
> > +	.feature_get = ifcvf_get_vdpa_feature,
> > +	.protocol_feature_get = ifcvf_get_protocol_feature,
> 
> I have proposed in vDPA series to rename the ops so that it is
> consistant with Vhost-user protocol:
> e.g. get_protocol_features, get_features...
> 
> So you might have to rebase if this is change is implemented.
> 

Will rebase on the latest vDPA series.

Thanks,
Xiao