04b67e18ce
In the old Shared VLAN Learning mode of operation that tag_8021q previously used for forwarding, we needed to have distinct concepts for an RX and a TX VLAN. An RX VLAN could be installed on all ports that were members of a given bridge, so that autonomous forwarding could still work, while a TX VLAN was dedicated for precise packet steering, so it just contained the CPU port and one egress port. Now that tag_8021q uses Independent VLAN Learning and imprecise RX/TX all over, those lines have been blurred and we no longer have the need to do precise TX towards a port that is in a bridge. As for standalone ports, it is fine to use the same VLAN ID for both RX and TX. This patch changes the tag_8021q format by shifting the VLAN range it reserves, and halving it. Previously, our DIR bits were encoding the VLAN direction (RX/TX) and were set to either 1 or 2. This meant that tag_8021q reserved 2K VLANs, or 50% of the available range. Change the DIR bits to a hardcoded value of 3 now, which makes tag_8021q reserve only 1K VLANs, and a different range now (the last 1K). This is done so that we leave the old format in place in case we need to return to it. In terms of code, the vid_is_dsa_8021q_rxvlan and vid_is_dsa_8021q_txvlan functions go away. Any vid_is_dsa_8021q is both a TX and an RX VLAN, and they are no longer distinct. For example, felix which did different things for different VLAN types, now needs to handle the RX and the TX logic for the same VLAN. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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.