mainlining shenanigans
ee80dd2e89
Introduce a brother of br_vlan_get_info() which is protected by the RCU mechanism, as opposed to br_vlan_get_info() which relies on taking the write-side rtnl_mutex. This is needed for drivers which need to find out whether a bridge port has a VLAN configured or not. For example, certain DSA switches might not offer complete source port identification to the CPU on RX, just the VLAN in which the packet was received. Based on this VLAN, we cannot set an accurate skb->dev ingress port, but at least we can configure one that behaves the same as the correct one would (this is possible because DSA sets skb->offload_fwd_mark = 1). When we look at the bridge RX handler (br_handle_frame), we see that what matters regarding skb->dev is the VLAN ID and the port STP state. So we need to select an skb->dev that has the same bridge VLAN as the packet we're receiving, and is in the LEARNING or FORWARDING STP state. The latter is easy, but for the former, we should somehow keep a shadow list of the bridge VLANs on each port, and a lookup table between VLAN ID and the 'designated port for imprecise RX'. That is rather complicated to keep in sync properly (the designated port per VLAN needs to be updated on the addition and removal of a VLAN, as well as on the join/leave events of the bridge on that port). So, to avoid all that complexity, let's just iterate through our finite number of ports and ask the bridge, for each packet: "do you have this VLAN configured on this port?". Cc: Roopa Prabhu <roopa@nvidia.com> Cc: Nikolay Aleksandrov <nikolay@nvidia.com> Cc: Ido Schimmel <idosch@nvidia.com> Cc: Jiri Pirko <jiri@nvidia.com> Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net> |
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| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.