ccb6ed426f
Ocelot switches perform port-based ingress mirroring if ANA:PORT:PORT_CFG field SRC_MIRROR_ENA is set, and egress mirroring if the port is in ANA:ANA:EMIRRORPORTS. Both ingress-mirrored and egress-mirrored frames are copied to the port mask from ANA:ANA:MIRRORPORTS. So the choice of limiting to a single mirror port via ocelot_mirror_get() and ocelot_mirror_put() may seem bizarre, but the hardware model doesn't map very well to the user space model. If the user wants to mirror the ingress of swp1 towards swp2 and the ingress of swp3 towards swp4, we'd have to program ANA:ANA:MIRRORPORTS with BIT(2) | BIT(4), and that would make swp1 be mirrored towards swp4 too, and swp3 towards swp2. But there are no tc-matchall rules to describe those actions. Now, we could offload a matchall rule with multiple mirred actions, one per desired mirror port, and force the user to stick to the multi-action rule format for subsequent matchall filters. But both DSA and ocelot have the flow_offload_has_one_action() check for the matchall offload, plus the fact that it will get cumbersome to cross-check matchall mirrors with flower mirrors (which will be added in the next patch). As a result, we limit the configuration to a single mirror port, with the possibility of lifting the restriction in the future. Frames injected from the CPU don't get egress-mirrored, since they are sent with the BYPASS bit in the injection frame header, and this bypasses the analyzer module (effectively also the mirroring logic). I don't know what to do/say about this. Functionality was tested with: tc qdisc add dev swp3 clsact tc filter add dev swp3 ingress \ matchall skip_sw \ action mirred egress mirror dev swp1 and pinging through swp3, while seeing that the ICMP replies are mirrored towards swp1. Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
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| LICENSES | ||
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| 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 | ||
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.