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Paul Greenwalt 905d1a220e ice: Add E830 checksum offload support
E830 supports raw receive and generic transmit checksum offloads.

Raw receive checksum support is provided by hardware calculating the
checksum over the whole packet, regardless of type. The calculated
checksum is provided to driver in the Rx flex descriptor. Then the driver
assigns the checksum to skb->csum and sets skb->ip_summed to
CHECKSUM_COMPLETE.

Generic transmit checksum support is provided by hardware calculating the
checksum given two offsets: the start offset to begin checksum calculation,
and the offset to insert the calculated checksum in the packet. Support is
advertised to the stack using NETIF_F_HW_CSUM feature.

E830 has the following limitations when both generic transmit checksum
offload and TCP Segmentation Offload (TSO) are enabled:

1. Inner packet header modification is not supported. This restriction
   includes the inability to alter TCP flags, such as the push flag. As a
   result, this limitation can impact the receiver's ability to coalesce
   packets, potentially degrading network throughput.
2. The Maximum Segment Size (MSS) is limited to 1023 bytes, which prevents
   support of Maximum Transmission Unit (MTU) greater than 1063 bytes.

Therefore NETIF_F_HW_CSUM and NETIF_F_ALL_TSO features are mutually
exclusive. NETIF_F_HW_CSUM hardware feature support is indicated but is not
enabled by default. Instead, IP checksums and NETIF_F_ALL_TSO are the
defaults. Enforcement of mutual exclusivity of NETIF_F_HW_CSUM and
NETIF_F_ALL_TSO is done in ice_set_features(). Mutual exclusivity
of IP checksums and NETIF_F_HW_CSUM is handled by netdev_fix_features().

When NETIF_F_HW_CSUM is requested the provided skb->csum_start and
skb->csum_offset are passed to hardware in the Tx context descriptor
generic checksum (GCS) parameters. Hardware calculates the 1's complement
from skb->csum_start to the end of the packet, and inserts the result in
the packet at skb->csum_offset.

Co-developed-by: Alice Michael <alice.michael@intel.com>
Signed-off-by: Alice Michael <alice.michael@intel.com>
Co-developed-by: Eric Joyner <eric.joyner@intel.com>
Signed-off-by: Eric Joyner <eric.joyner@intel.com>
Signed-off-by: Paul Greenwalt <paul.greenwalt@intel.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Tested-by: Rinitha S <sx.rinitha@intel.com> (A Contingent worker at Intel)
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Link: https://patch.msgid.link/20250310174502.3708121-2-anthony.l.nguyen@intel.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2025-03-18 10:15:49 +01:00
arch Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2025-03-13 23:08:11 +01:00
block block-6.14-20250306 2025-03-07 11:12:33 -10:00
certs sign-file,extract-cert: use pkcs11 provider for OPENSSL MAJOR >= 3 2024-09-20 19:52:48 +03:00
crypto treewide: const qualify ctl_tables where applicable 2025-01-28 13:48:37 +01:00
Documentation Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2025-03-13 23:08:11 +01:00
drivers ice: Add E830 checksum offload support 2025-03-18 10:15:49 +01:00
fs Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2025-03-13 23:08:11 +01:00
include net: phy: drop phy_settings and the associated lookup helpers 2025-03-18 09:03:11 +01:00
init Kbuild updates for v6.14 2025-01-31 12:07:07 -08:00
io_uring Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2025-03-13 23:08:11 +01:00
ipc treewide: const qualify ctl_tables where applicable 2025-01-28 13:48:37 +01:00
kernel Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2025-03-13 23:08:11 +01:00
lib Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2025-03-13 23:08:11 +01:00
LICENSES LICENSES: add 0BSD license text 2024-09-01 20:43:24 -07:00
mm 33 hotfixes. 24 are cc:stable and the remainder address post-6.13 issues 2025-03-08 14:34:06 -10:00
net net: ethtool: Export the link_mode_params definitions 2025-03-18 09:03:11 +01:00
rust Driver core api addition for 6.14-rc3 2025-02-16 12:54:42 -08:00
samples Driver core api addition for 6.14-rc3 2025-02-16 12:54:42 -08:00
scripts Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2025-03-13 23:08:11 +01:00
security Landlock fix for v6.14-rc5 2025-02-26 11:55:44 -08:00
sound ALSA: hda/realtek: Add support for ASUS Zenbook UM3406KA Laptops using CS35L41 HDA 2025-03-05 19:52:56 +01:00
tools selftests: drv-net: fix merge conflicts resolution 2025-03-14 10:24:14 +01:00
usr kbuild: hdrcheck: fix cross build with clang 2025-03-05 04:06:45 +09:00
virt KVM: remove kvm_arch_post_init_vm 2025-02-04 11:27:45 -05:00
.clang-format clang-format: Update with v6.11-rc1's for_each macro list 2024-08-02 13:20:31 +02:00
.clippy.toml rust: give Clippy the minimum supported Rust version 2025-01-10 00:17:25 +01:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.editorconfig .editorconfig: remove trim_trailing_whitespace option 2024-06-13 16:47:52 +02:00
.get_maintainer.ignore MAINTAINERS: Retire Ralf Baechle 2024-11-12 15:48:59 +01:00
.gitattributes .gitattributes: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore rust: use host dylib naming convention to support macOS 2025-01-10 01:01:24 +01:00
.mailmap 33 hotfixes. 24 are cc:stable and the remainder address post-6.13 issues 2025-03-08 14:34:06 -10:00
.rustfmt.toml rust: add .rustfmt.toml 2022-09-28 09:02:20 +02:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: Move Pavel to kernel.org address 2025-02-07 09:12:33 -08:00
Kbuild Kbuild updates for v6.1 2022-10-10 12:00:45 -07:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2025-03-13 23:08:11 +01:00
Makefile Linux 6.14-rc6 2025-03-09 13:45:25 -10:00
README README: Fix spelling 2024-03-18 03:36:32 -06:00

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 reStructuredText 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.