Parav Pandit Says:
=================
This patchset introduces support for mlx5 subfunction (SF).
A subfunction is a lightweight function that has a parent PCI function on
which it is deployed. mlx5 subfunction has its own function capabilities
and its own resources. This means a subfunction has its own dedicated
queues(txq, rxq, cq, eq). These queues are neither shared nor stolen from
the parent PCI function.
When subfunction is RDMA capable, it has its own QP1, GID table and rdma
resources neither shared nor stolen from the parent PCI function.
A subfunction has dedicated window in PCI BAR space that is not shared
with the other subfunctions or parent PCI function. This ensures that all
class devices of the subfunction accesses only assigned PCI BAR space.
A Subfunction supports eswitch representation through which it supports tc
offloads. User must configure eswitch to send/receive packets from/to
subfunction port.
Subfunctions share PCI level resources such as PCI MSI-X IRQs with
their other subfunctions and/or with its parent PCI function.
Patch summary:
--------------
Patch 1 to 4 prepares devlink
patch 5 to 7 mlx5 adds SF device support
Patch 8 to 11 mlx5 adds SF devlink port support
Patch 12 and 14 adds documentation
Patch-1 prepares code to handle multiple port function attributes
Patch-2 introduces devlink pcisf port flavour similar to pcipf and pcivf
Patch-3 adds port add and delete driver callbacks
Patch-4 adds port function state get and set callbacks
Patch-5 mlx5 vhca event notifier support to distribute subfunction
state change notification
Patch-6 adds SF auxiliary device
Patch-7 adds SF auxiliary driver
Patch-8 prepares eswitch to handler SF vport
Patch-9 adds eswitch helpers to add/remove SF vport
Patch-10 implements devlink port add/del callbacks
Patch-11 implements devlink port function get/set callbacks
Patch-12 to 14 adds documentation
Patch-12 added mlx5 port function documentation
Patch-13 adds subfunction documentation
Patch-14 adds mlx5 subfunction documentation
Subfunction support is discussed in detail in RFC [1] and [2].
RFC [1] and extension [2] describes requirements, design and proposed
plumbing using devlink, auxiliary bus and sysfs for systemd/udev
support. Functionality of this patchset is best explained using real
examples further below.
overview:
--------
A subfunction can be created and deleted by a user using devlink port
add/delete interface.
A subfunction can be configured using devlink port function attribute
before its activated.
When a subfunction is activated, it results in an auxiliary device on
the host PCI device where it is deployed. A driver binds to the
auxiliary device that further creates supported class devices.
example subfunction usage sequence:
-----------------------------------
Change device to switchdev mode:
$ devlink dev eswitch set pci/0000:06:00.0 mode switchdev
Add a devlink port of subfunction flavour:
$ devlink port add pci/0000:06:00.0 flavour pcisf pfnum 0 sfnum 88
Configure mac address of the port function:
$ devlink port function set ens2f0npf0sf88 hw_addr 00:00:00:00:88:88
Now activate the function:
$ devlink port function set ens2f0npf0sf88 state active
Now use the auxiliary device and class devices:
$ devlink dev show
pci/0000:06:00.0
auxiliary/mlx5_core.sf.4
$ ip link show
127: ens2f0np0: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
link/ether 24:8a:07:b3:d1:12 brd ff:ff:ff:ff:ff:ff
altname enp6s0f0np0
129: p0sf88: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
link/ether 00:00:00:00:88:88 brd ff:ff:ff:ff:ff:ff
$ rdma dev show
43: rdmap6s0f0: node_type ca fw 16.29.0550 node_guid 248a:0703:00b3:d112 sys_image_guid 248a:0703:00b3:d112
44: mlx5_0: node_type ca fw 16.29.0550 node_guid 0000:00ff:fe00:8888 sys_image_guid 248a:0703:00b3:d112
After use inactivate the function:
$ devlink port function set ens2f0npf0sf88 state inactive
Now delete the subfunction port:
$ devlink port del ens2f0npf0sf88
[1] https://lore.kernel.org/netdev/20200519092258.GF4655@nanopsycho/
[2] https://marc.info/?l=linux-netdev&m=158555928517777&w=2
=================
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Merge tag 'mlx5-updates-2021-01-13' of git://git.kernel.org/pub/scm/linux/kernel/git/saeed/linux
Saeed Mahameed says:
====================
mlx5 subfunction support
Parav Pandit says:
This patchset introduces support for mlx5 subfunction (SF).
A subfunction is a lightweight function that has a parent PCI function on
which it is deployed. mlx5 subfunction has its own function capabilities
and its own resources. This means a subfunction has its own dedicated
queues(txq, rxq, cq, eq). These queues are neither shared nor stolen from
the parent PCI function.
When subfunction is RDMA capable, it has its own QP1, GID table and rdma
resources neither shared nor stolen from the parent PCI function.
A subfunction has dedicated window in PCI BAR space that is not shared
with the other subfunctions or parent PCI function. This ensures that all
class devices of the subfunction accesses only assigned PCI BAR space.
A Subfunction supports eswitch representation through which it supports tc
offloads. User must configure eswitch to send/receive packets from/to
subfunction port.
Subfunctions share PCI level resources such as PCI MSI-X IRQs with
their other subfunctions and/or with its parent PCI function.
Subfunction support is discussed in detail in RFC [1] and [2].
RFC [1] and extension [2] describes requirements, design and proposed
plumbing using devlink, auxiliary bus and sysfs for systemd/udev
support. Functionality of this patchset is best explained using real
examples further below.
overview:
--------
A subfunction can be created and deleted by a user using devlink port
add/delete interface.
A subfunction can be configured using devlink port function attribute
before its activated.
When a subfunction is activated, it results in an auxiliary device on
the host PCI device where it is deployed. A driver binds to the
auxiliary device that further creates supported class devices.
example subfunction usage sequence:
-----------------------------------
Change device to switchdev mode:
$ devlink dev eswitch set pci/0000:06:00.0 mode switchdev
Add a devlink port of subfunction flavour:
$ devlink port add pci/0000:06:00.0 flavour pcisf pfnum 0 sfnum 88
Configure mac address of the port function:
$ devlink port function set ens2f0npf0sf88 hw_addr 00:00:00:00:88:88
Now activate the function:
$ devlink port function set ens2f0npf0sf88 state active
Now use the auxiliary device and class devices:
$ devlink dev show
pci/0000:06:00.0
auxiliary/mlx5_core.sf.4
$ ip link show
127: ens2f0np0: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
link/ether 24:8a:07:b3:d1:12 brd ff:ff:ff:ff:ff:ff
altname enp6s0f0np0
129: p0sf88: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
link/ether 00:00:00:00:88:88 brd ff:ff:ff:ff:ff:ff
$ rdma dev show
43: rdmap6s0f0: node_type ca fw 16.29.0550 node_guid 248a:0703:00b3:d112 sys_image_guid 248a:0703:00b3:d112
44: mlx5_0: node_type ca fw 16.29.0550 node_guid 0000:00ff:fe00:8888 sys_image_guid 248a:0703:00b3:d112
After use inactivate the function:
$ devlink port function set ens2f0npf0sf88 state inactive
Now delete the subfunction port:
$ devlink port del ens2f0npf0sf88
[1] https://lore.kernel.org/netdev/20200519092258.GF4655@nanopsycho/
[2] https://marc.info/?l=linux-netdev&m=158555928517777&w=2
=================
* tag 'mlx5-updates-2021-01-13' of git://git.kernel.org/pub/scm/linux/kernel/git/saeed/linux:
net/mlx5: Add devlink subfunction port documentation
devlink: Extend devlink port documentation for subfunctions
devlink: Add devlink port documentation
net/mlx5: SF, Port function state change support
net/mlx5: SF, Add port add delete functionality
net/mlx5: E-switch, Add eswitch helpers for SF vport
net/mlx5: E-switch, Prepare eswitch to handle SF vport
net/mlx5: SF, Add auxiliary device driver
net/mlx5: SF, Add auxiliary device support
net/mlx5: Introduce vhca state event notifier
devlink: Support get and set state of port function
devlink: Support add and delete devlink port
devlink: Introduce PCI SF port flavour and port attribute
devlink: Prepare code to fill multiple port function attributes
====================
Link: https://lore.kernel.org/r/20210122193658.282884-1-saeed@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
24a790da0a