Timo Völker
c1fa70c6e9
Always offer the VIRTIO_NET_F_GUEST_CSUM feature to the host, and not only if RXCSUM is enabled on vtnet. Instead of using RXCSUM to control whether this feature will be negotiated with the host, just use it to control whether the VIRTIO_NET_HDR_F_DATA_VALID flag on an incoming packet is processed (i.e., translated to the corresponding mbuf flag only if RXCSUM is enabled on the vtnet interface). This has two benefits: 1. Enabling/disabling RXCSUM on vtnet does not require feature renegotiation. 2. The host is always allowed to send locally generated TCP or UDP packets to the guest without computing a full checksum (by setting the VIRTIO_NET_HDR_F_NEEDS_CSUM flag) and not only if the guest has enabled RXCSUM on vtnet. Since locally generated packets do not require a checksum, this saves otherwise unnecessarily wasted computing power. If a user of a FreeBSD guest really does not want to negotiate the VIRTIO_NET_F_GUEST_CSUM feature with the host, it still can disable the loader tunable hw.vtnet.csum_disable. Reviewed by: kfv, tuexen MFC after: 1 week MFC to: stable/15 Differential Revision: https://reviews.freebsd.org/D59052
FreeBSD Source:
This is the top level of the FreeBSD source directory.
FreeBSD is an operating system used to power modern servers, desktops, and embedded platforms. A large community has continually developed it for more than thirty years. Its advanced networking, security, and storage features have made FreeBSD the platform of choice for many of the busiest web sites and most pervasive embedded networking and storage devices.
For copyright information, please see the file COPYRIGHT in this directory. Additional copyright information also exists for some sources in this tree - please see the specific source directories for more information.
The Makefile in this directory supports a number of targets for building components (or all) of the FreeBSD source tree. See build(7), config(8), FreeBSD handbook on building userland, and Handbook for kernels for more information, including setting make(1) variables.
For information on the CPU architectures and platforms supported by FreeBSD, see the FreeBSD website's Platforms page.
For official FreeBSD bootable images, see the release page.
Source Roadmap:
| Directory | Description |
|---|---|
| bin | System/user commands. |
| cddl | Source code for third-party software under the Common Development and Distribution License. |
| contrib | Source code for third-party software. |
| crypto | Source code for cryptographic libraries and commands (see crypto/README). |
| etc | Template files for /etc. |
| include | System include files. |
| kerberos5 | Build system for Kerberos 5 (Heimdal). |
| krb5 | Build system for Kerberos 5 (MIT). |
| lib | System libraries. |
| libexec | System commands intended to be executed by other commands or daemons. |
| packages | Base system packages. |
| release | Makefiles and scripts used for building releases and VM images. |
| rescue | Build system for statically linked /rescue commands. |
| sbin | System commands. |
| secure | Build system for cryptographic libraries and commands (excluding Kerberos). |
| share | Shared resources. |
| stand | Boot loader sources. |
| sys | Kernel sources (see sys/README.md). |
| targets | Support for experimental DIRDEPS_BUILD |
| tests | Tests which can be run by Kyua. See tests/README for additional information. |
| tools | Ancillary utilities and tests (not included in the build). |
| usr.bin | User commands. |
| usr.sbin | System administration commands. |
For information on synchronizing your source tree with one or more of the FreeBSD Project's development branches, please see FreeBSD Handbook.