mirror of
https://github.com/torvalds/linux.git
synced 2024-11-26 14:12:06 +00:00
A mirror of the official Linux kernel repository just in case
e5d1f896fd
There is one main difference in mscc_ocelot between IP multicast and L2 multicast. With IP multicast, destination ports are encoded into the upper bytes of the multicast MAC address. Example: to deliver the address 01:00:5E:11:22:33 to ports 3, 8, and 9, one would need to program the address of 00:03:08:11:22:33 into hardware. Whereas for L2 multicast, the MAC table entry points to a Port Group ID (PGID), and that PGID contains the port mask that the packet will be forwarded to. As to why it is this way, no clue. My guess is that not all port combinations can be supported simultaneously with the limited number of PGIDs, and this was somehow an issue for IP multicast but not for L2 multicast. Anyway. Prior to this change, the raw L2 multicast code was bogus, due to the fact that there wasn't really any way to test it using the bridge code. There were 2 issues: - A multicast PGID was allocated for each MDB entry, but it wasn't in fact programmed to hardware. It was dummy. - In fact we don't want to reserve a multicast PGID for every single MDB entry. That would be odd because we can only have ~60 PGIDs, but thousands of MDB entries. So instead, we want to reserve a multicast PGID for every single port combination for multicast traffic. And since we can have 2 (or more) MDB entries delivered to the same port group (and therefore PGID), we need to reference-count the PGIDs. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
||
|---|---|---|
| arch | ||
| block | ||
| 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.