diff options
Diffstat (limited to 'Documentation/networking')
| -rw-r--r-- | Documentation/networking/00-INDEX | 2 | ||||
| -rw-r--r-- | Documentation/networking/batman-adv.rst | 2 | ||||
| -rw-r--r-- | Documentation/networking/dsa/dsa.txt | 5 | ||||
| -rw-r--r-- | Documentation/networking/ieee802154.txt | 40 | ||||
| -rw-r--r-- | Documentation/networking/ip-sysctl.txt | 1 | ||||
| -rw-r--r-- | Documentation/networking/kapi.rst | 24 | ||||
| -rw-r--r-- | Documentation/networking/netdev-features.txt | 9 | ||||
| -rw-r--r-- | Documentation/networking/xfrm_device.txt | 132 | ||||
| -rw-r--r-- | Documentation/networking/xfrm_proc.txt | 20 |
9 files changed, 224 insertions, 11 deletions
diff --git a/Documentation/networking/00-INDEX b/Documentation/networking/00-INDEX index 7a79b3587dd3..f5d642c01dd3 100644 --- a/Documentation/networking/00-INDEX +++ b/Documentation/networking/00-INDEX @@ -228,6 +228,8 @@ x25.txt - general info on X.25 development. x25-iface.txt - description of the X.25 Packet Layer to LAPB device interface. +xfrm_device.txt + - description of XFRM offload API xfrm_proc.txt - description of the statistics package for XFRM. xfrm_sync.txt diff --git a/Documentation/networking/batman-adv.rst b/Documentation/networking/batman-adv.rst index a342b2cc3dc6..245fb6c0ab6f 100644 --- a/Documentation/networking/batman-adv.rst +++ b/Documentation/networking/batman-adv.rst @@ -1,3 +1,5 @@ +.. SPDX-License-Identifier: GPL-2.0 + ========== batman-adv ========== diff --git a/Documentation/networking/dsa/dsa.txt b/Documentation/networking/dsa/dsa.txt index b8b40753133e..25170ad7d25b 100644 --- a/Documentation/networking/dsa/dsa.txt +++ b/Documentation/networking/dsa/dsa.txt @@ -385,11 +385,6 @@ Switch configuration avoid relying on what a previous software agent such as a bootloader/firmware may have previously configured. -- set_addr: Some switches require the programming of the management interface's - Ethernet MAC address, switch drivers can also disable ageing of MAC addresses - on the management interface and "hardcode"/"force" this MAC address for the - CPU/management interface as an optimization - PHY devices and link management ------------------------------- diff --git a/Documentation/networking/ieee802154.txt b/Documentation/networking/ieee802154.txt index 057e9fdbfac9..e74d8e1da0e2 100644 --- a/Documentation/networking/ieee802154.txt +++ b/Documentation/networking/ieee802154.txt @@ -97,6 +97,46 @@ The include/net/mac802154.h defines following functions: - void ieee802154_unregister_hw(struct ieee802154_hw *hw): freeing registered PHY + - void ieee802154_rx_irqsafe(struct ieee802154_hw *hw, struct sk_buff *skb, + u8 lqi): + telling 802.15.4 module there is a new received frame in the skb with + the RF Link Quality Indicator (LQI) from the hardware device + + - void ieee802154_xmit_complete(struct ieee802154_hw *hw, struct sk_buff *skb, + bool ifs_handling): + telling 802.15.4 module the frame in the skb is or going to be + transmitted through the hardware device + +The device driver must implement the following callbacks in the IEEE 802.15.4 +operations structure at least: +struct ieee802154_ops { + ... + int (*start)(struct ieee802154_hw *hw); + void (*stop)(struct ieee802154_hw *hw); + ... + int (*xmit_async)(struct ieee802154_hw *hw, struct sk_buff *skb); + int (*ed)(struct ieee802154_hw *hw, u8 *level); + int (*set_channel)(struct ieee802154_hw *hw, u8 page, u8 channel); + ... +}; + + - int start(struct ieee802154_hw *hw): + handler that 802.15.4 module calls for the hardware device initialization. + + - void stop(struct ieee802154_hw *hw): + handler that 802.15.4 module calls for the hardware device cleanup. + + - int xmit_async(struct ieee802154_hw *hw, struct sk_buff *skb): + handler that 802.15.4 module calls for each frame in the skb going to be + transmitted through the hardware device. + + - int ed(struct ieee802154_hw *hw, u8 *level): + handler that 802.15.4 module calls for Energy Detection from the hardware + device. + + - int set_channel(struct ieee802154_hw *hw, u8 page, u8 channel): + set radio for listening on specific channel of the hardware device. + Moreover IEEE 802.15.4 device operations structure should be filled. Fake drivers diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt index 46c7e1085efc..3f2c40d8e6aa 100644 --- a/Documentation/networking/ip-sysctl.txt +++ b/Documentation/networking/ip-sysctl.txt @@ -606,6 +606,7 @@ tcp_fastopen_blackhole_timeout_sec - INTEGER This time period will grow exponentially when more blackhole issues get detected right after Fastopen is re-enabled and will reset to initial value when the blackhole issue goes away. + 0 to disable the blackhole detection. By default, it is set to 1hr. tcp_syn_retries - INTEGER diff --git a/Documentation/networking/kapi.rst b/Documentation/networking/kapi.rst index 580289f345da..f03ae64be8bc 100644 --- a/Documentation/networking/kapi.rst +++ b/Documentation/networking/kapi.rst @@ -145,3 +145,27 @@ PHY Support .. kernel-doc:: drivers/net/phy/mdio_bus.c :internal: + +PHYLINK +------- + + PHYLINK interfaces traditional network drivers with PHYLIB, fixed-links, + and SFF modules (eg, hot-pluggable SFP) that may contain PHYs. PHYLINK + provides management of the link state and link modes. + +.. kernel-doc:: include/linux/phylink.h + :internal: + +.. kernel-doc:: drivers/net/phy/phylink.c + +SFP support +----------- + +.. kernel-doc:: drivers/net/phy/sfp-bus.c + :internal: + +.. kernel-doc:: include/linux/sfp.h + :internal: + +.. kernel-doc:: drivers/net/phy/sfp-bus.c + :export: diff --git a/Documentation/networking/netdev-features.txt b/Documentation/networking/netdev-features.txt index 7413eb05223b..c77f9d57eb91 100644 --- a/Documentation/networking/netdev-features.txt +++ b/Documentation/networking/netdev-features.txt @@ -163,3 +163,12 @@ This requests that the NIC receive all possible frames, including errored frames (such as bad FCS, etc). This can be helpful when sniffing a link with bad packets on it. Some NICs may receive more packets if also put into normal PROMISC mode. + +* rx-gro-hw + +This requests that the NIC enables Hardware GRO (generic receive offload). +Hardware GRO is basically the exact reverse of TSO, and is generally +stricter than Hardware LRO. A packet stream merged by Hardware GRO must +be re-segmentable by GSO or TSO back to the exact original packet stream. +Hardware GRO is dependent on RXCSUM since every packet successfully merged +by hardware must also have the checksum verified by hardware. diff --git a/Documentation/networking/xfrm_device.txt b/Documentation/networking/xfrm_device.txt new file mode 100644 index 000000000000..2d9d588cd34b --- /dev/null +++ b/Documentation/networking/xfrm_device.txt @@ -0,0 +1,132 @@ + +=============================================== +XFRM device - offloading the IPsec computations +=============================================== +Shannon Nelson <shannon.nelson@oracle.com> + + +Overview +======== + +IPsec is a useful feature for securing network traffic, but the +computational cost is high: a 10Gbps link can easily be brought down +to under 1Gbps, depending on the traffic and link configuration. +Luckily, there are NICs that offer a hardware based IPsec offload which +can radically increase throughput and decrease CPU utilization. The XFRM +Device interface allows NIC drivers to offer to the stack access to the +hardware offload. + +Userland access to the offload is typically through a system such as +libreswan or KAME/raccoon, but the iproute2 'ip xfrm' command set can +be handy when experimenting. An example command might look something +like this: + + ip x s add proto esp dst 14.0.0.70 src 14.0.0.52 spi 0x07 mode transport \ + reqid 0x07 replay-window 32 \ + aead 'rfc4106(gcm(aes))' 0x44434241343332312423222114131211f4f3f2f1 128 \ + sel src 14.0.0.52/24 dst 14.0.0.70/24 proto tcp \ + offload dev eth4 dir in + +Yes, that's ugly, but that's what shell scripts and/or libreswan are for. + + + +Callbacks to implement +====================== + +/* from include/linux/netdevice.h */ +struct xfrmdev_ops { + int (*xdo_dev_state_add) (struct xfrm_state *x); + void (*xdo_dev_state_delete) (struct xfrm_state *x); + void (*xdo_dev_state_free) (struct xfrm_state *x); + bool (*xdo_dev_offload_ok) (struct sk_buff *skb, + struct xfrm_state *x); +}; + +The NIC driver offering ipsec offload will need to implement these +callbacks to make the offload available to the network stack's +XFRM subsytem. Additionally, the feature bits NETIF_F_HW_ESP and +NETIF_F_HW_ESP_TX_CSUM will signal the availability of the offload. + + + +Flow +==== + +At probe time and before the call to register_netdev(), the driver should +set up local data structures and XFRM callbacks, and set the feature bits. +The XFRM code's listener will finish the setup on NETDEV_REGISTER. + + adapter->netdev->xfrmdev_ops = &ixgbe_xfrmdev_ops; + adapter->netdev->features |= NETIF_F_HW_ESP; + adapter->netdev->hw_enc_features |= NETIF_F_HW_ESP; + +When new SAs are set up with a request for "offload" feature, the +driver's xdo_dev_state_add() will be given the new SA to be offloaded +and an indication of whether it is for Rx or Tx. The driver should + - verify the algorithm is supported for offloads + - store the SA information (key, salt, target-ip, protocol, etc) + - enable the HW offload of the SA + +The driver can also set an offload_handle in the SA, an opaque void pointer +that can be used to convey context into the fast-path offload requests. + + xs->xso.offload_handle = context; + + +When the network stack is preparing an IPsec packet for an SA that has +been setup for offload, it first calls into xdo_dev_offload_ok() with +the skb and the intended offload state to ask the driver if the offload +will serviceable. This can check the packet information to be sure the +offload can be supported (e.g. IPv4 or IPv6, no IPv4 options, etc) and +return true of false to signify its support. + +When ready to send, the driver needs to inspect the Tx packet for the +offload information, including the opaque context, and set up the packet +send accordingly. + + xs = xfrm_input_state(skb); + context = xs->xso.offload_handle; + set up HW for send + +The stack has already inserted the appropriate IPsec headers in the +packet data, the offload just needs to do the encryption and fix up the +header values. + + +When a packet is received and the HW has indicated that it offloaded a +decryption, the driver needs to add a reference to the decoded SA into +the packet's skb. At this point the data should be decrypted but the +IPsec headers are still in the packet data; they are removed later up +the stack in xfrm_input(). + + find and hold the SA that was used to the Rx skb + get spi, protocol, and destination IP from packet headers + xs = find xs from (spi, protocol, dest_IP) + xfrm_state_hold(xs); + + store the state information into the skb + skb->sp = secpath_dup(skb->sp); + skb->sp->xvec[skb->sp->len++] = xs; + skb->sp->olen++; + + indicate the success and/or error status of the offload + xo = xfrm_offload(skb); + xo->flags = CRYPTO_DONE; + xo->status = crypto_status; + + hand the packet to napi_gro_receive() as usual + + +When the SA is removed by the user, the driver's xdo_dev_state_delete() +is asked to disable the offload. Later, xdo_dev_state_free() is called +from a garbage collection routine after all reference counts to the state +have been removed and any remaining resources can be cleared for the +offload state. How these are used by the driver will depend on specific +hardware needs. + +As a netdev is set to DOWN the XFRM stack's netdev listener will call +xdo_dev_state_delete() and xdo_dev_state_free() on any remaining offloaded +states. + + diff --git a/Documentation/networking/xfrm_proc.txt b/Documentation/networking/xfrm_proc.txt index d0d8bafa9016..2eae619ab67b 100644 --- a/Documentation/networking/xfrm_proc.txt +++ b/Documentation/networking/xfrm_proc.txt @@ -5,13 +5,15 @@ Masahide NAKAMURA <nakam@linux-ipv6.org> Transformation Statistics ------------------------- -xfrm_proc is a statistics shown factor dropped by transformation -for developer. -It is a counter designed from current transformation source code -and defined like linux private MIB. -Inbound statistics -~~~~~~~~~~~~~~~~~~ +The xfrm_proc code is a set of statistics showing numbers of packets +dropped by the transformation code and why. These counters are defined +as part of the linux private MIB. These counters can be viewed in +/proc/net/xfrm_stat. + + +Inbound errors +~~~~~~~~~~~~~~ XfrmInError: All errors which is not matched others XfrmInBufferError: @@ -46,6 +48,10 @@ XfrmInPolBlock: Policy discards XfrmInPolError: Policy error +XfrmAcquireError: + State hasn't been fully acquired before use +XfrmFwdHdrError: + Forward routing of a packet is not allowed Outbound errors ~~~~~~~~~~~~~~~ @@ -72,3 +78,5 @@ XfrmOutPolDead: Policy is dead XfrmOutPolError: Policy error +XfrmOutStateInvalid: + State is invalid, perhaps expired |