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authorLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
committerLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
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Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted
Pull networking updates from Jakub Kicinski: "Core: - Add dedicated kmem_cache for typical/small skb->head, avoid having to access struct page at kfree time, and improve memory use. - Introduce sysctl to set default RPS configuration for new netdevs. - Define Netlink protocol specification format which can be used to describe messages used by each family and auto-generate parsers. Add tools for generating kernel data structures and uAPI headers. - Expose all net/core sysctls inside netns. - Remove 4s sleep in netpoll if carrier is instantly detected on boot. - Add configurable limit of MDB entries per port, and port-vlan. - Continue populating drop reasons throughout the stack. - Retire a handful of legacy Qdiscs and classifiers. Protocols: - Support IPv4 big TCP (TSO frames larger than 64kB). - Add IP_LOCAL_PORT_RANGE socket option, to control local port range on socket by socket basis. - Track and report in procfs number of MPTCP sockets used. - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path manager. - IPv6: don't check net.ipv6.route.max_size and rely on garbage collection to free memory (similarly to IPv4). - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986). - ICMP: add per-rate limit counters. - Add support for user scanning requests in ieee802154. - Remove static WEP support. - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate reporting. - WiFi 7 EHT channel puncturing support (client & AP). BPF: - Add a rbtree data structure following the "next-gen data structure" precedent set by recently added linked list, that is, by using kfunc + kptr instead of adding a new BPF map type. - Expose XDP hints via kfuncs with initial support for RX hash and timestamp metadata. - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to better support decap on GRE tunnel devices not operating in collect metadata. - Improve x86 JIT's codegen for PROBE_MEM runtime error checks. - Remove the need for trace_printk_lock for bpf_trace_printk and bpf_trace_vprintk helpers. - Extend libbpf's bpf_tracing.h support for tracing arguments of kprobes/uprobes and syscall as a special case. - Significantly reduce the search time for module symbols by livepatch and BPF. - Enable cpumasks to be used as kptrs, which is useful for tracing programs tracking which tasks end up running on which CPUs in different time intervals. - Add support for BPF trampoline on s390x and riscv64. - Add capability to export the XDP features supported by the NIC. - Add __bpf_kfunc tag for marking kernel functions as kfuncs. - Add cgroup.memory=nobpf kernel parameter option to disable BPF memory accounting for container environments. Netfilter: - Remove the CLUSTERIP target. It has been marked as obsolete for years, and we still have WARN splats wrt races of the out-of-band /proc interface installed by this target. - Add 'destroy' commands to nf_tables. They are identical to the existing 'delete' commands, but do not return an error if the referenced object (set, chain, rule...) did not exist. Driver API: - Improve cpumask_local_spread() locality to help NICs set the right IRQ affinity on AMD platforms. - Separate C22 and C45 MDIO bus transactions more clearly. - Introduce new DCB table to control DSCP rewrite on egress. - Support configuration of Physical Layer Collision Avoidance (PLCA) Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of shared medium Ethernet. - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing preemption of low priority frames by high priority frames. - Add support for controlling MACSec offload using netlink SET. - Rework devlink instance refcounts to allow registration and de-registration under the instance lock. Split the code into multiple files, drop some of the unnecessarily granular locks and factor out common parts of netlink operation handling. - Add TX frame aggregation parameters (for USB drivers). - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning messages with notifications for debug. - Allow offloading of UDP NEW connections via act_ct. - Add support for per action HW stats in TC. - Support hardware miss to TC action (continue processing in SW from a specific point in the action chain). - Warn if old Wireless Extension user space interface is used with modern cfg80211/mac80211 drivers. Do not support Wireless Extensions for Wi-Fi 7 devices at all. Everyone should switch to using nl80211 interface instead. - Improve the CAN bit timing configuration. Use extack to return error messages directly to user space, update the SJW handling, including the definition of a new default value that will benefit CAN-FD controllers, by increasing their oscillator tolerance. New hardware / drivers: - Ethernet: - nVidia BlueField-3 support (control traffic driver) - Ethernet support for imx93 SoCs - Motorcomm yt8531 gigabit Ethernet PHY - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA) - Microchip LAN8841 PHY (incl. cable diagnostics and PTP) - Amlogic gxl MDIO mux - WiFi: - RealTek RTL8188EU (rtl8xxxu) - Qualcomm Wi-Fi 7 devices (ath12k) - CAN: - Renesas R-Car V4H Drivers: - Bluetooth: - Set Per Platform Antenna Gain (PPAG) for Intel controllers. - Ethernet NICs: - Intel (1G, igc): - support TSN / Qbv / packet scheduling features of i226 model - Intel (100G, ice): - use GNSS subsystem instead of TTY - multi-buffer XDP support - extend support for GPIO pins to E823 devices - nVidia/Mellanox: - update the shared buffer configuration on PFC commands - implement PTP adjphase function for HW offset control - TC support for Geneve and GRE with VF tunnel offload - more efficient crypto key management method - multi-port eswitch support - Netronome/Corigine: - add DCB IEEE support - support IPsec offloading for NFP3800 - Freescale/NXP (enetc): - support XDP_REDIRECT for XDP non-linear buffers - improve reconfig, avoid link flap and waiting for idle - support MAC Merge layer - Other NICs: - sfc/ef100: add basic devlink support for ef100 - ionic: rx_push mode operation (writing descriptors via MMIO) - bnxt: use the auxiliary bus abstraction for RDMA - r8169: disable ASPM and reset bus in case of tx timeout - cpsw: support QSGMII mode for J721e CPSW9G - cpts: support pulse-per-second output - ngbe: add an mdio bus driver - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing - r8152: handle devices with FW with NCM support - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation - virtio-net: support multi buffer XDP - virtio/vsock: replace virtio_vsock_pkt with sk_buff - tsnep: XDP support - Ethernet high-speed switches: - nVidia/Mellanox (mlxsw): - add support for latency TLV (in FW control messages) - Microchip (sparx5): - separate explicit and implicit traffic forwarding rules, make the implicit rules always active - add support for egress DSCP rewrite - IS0 VCAP support (Ingress Classification) - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS etc.) - ES2 VCAP support (Egress Access Control) - support for Per-Stream Filtering and Policing (802.1Q, 8.6.5.1) - Ethernet embedded switches: - Marvell (mv88e6xxx): - add MAB (port auth) offload support - enable PTP receive for mv88e6390 - NXP (ocelot): - support MAC Merge layer - support for the the vsc7512 internal copper phys - Microchip: - lan9303: convert to PHYLINK - lan966x: support TC flower filter statistics - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x - lan937x: support Credit Based Shaper configuration - ksz9477: support Energy Efficient Ethernet - other: - qca8k: convert to regmap read/write API, use bulk operations - rswitch: Improve TX timestamp accuracy - Intel WiFi (iwlwifi): - EHT (Wi-Fi 7) rate reporting - STEP equalizer support: transfer some STEP (connection to radio on platforms with integrated wifi) related parameters from the BIOS to the firmware. - Qualcomm 802.11ax WiFi (ath11k): - IPQ5018 support - Fine Timing Measurement (FTM) responder role support - channel 177 support - MediaTek WiFi (mt76): - per-PHY LED support - mt7996: EHT (Wi-Fi 7) support - Wireless Ethernet Dispatch (WED) reset support - switch to using page pool allocator - RealTek WiFi (rtw89): - support new version of Bluetooth co-existance - Mobile: - rmnet: support TX aggregation" * tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits) page_pool: add a comment explaining the fragment counter usage net: ethtool: fix __ethtool_dev_mm_supported() implementation ethtool: pse-pd: Fix double word in comments xsk: add linux/vmalloc.h to xsk.c sefltests: netdevsim: wait for devlink instance after netns removal selftest: fib_tests: Always cleanup before exit net/mlx5e: Align IPsec ASO result memory to be as required by hardware net/mlx5e: TC, Set CT miss to the specific ct action instance net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG net/mlx5: Refactor tc miss handling to a single function net/mlx5: Kconfig: Make tc offload depend on tc skb extension net/sched: flower: Support hardware miss to tc action net/sched: flower: Move filter handle initialization earlier net/sched: cls_api: Support hardware miss to tc action net/sched: Rename user cookie and act cookie sfc: fix builds without CONFIG_RTC_LIB sfc: clean up some inconsistent indentings net/mlx4_en: Introduce flexible array to silence overflow warning net: lan966x: Fix possible deadlock inside PTP net/ulp: Remove redundant ->clone() test in inet_clone_ulp(). ...
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+.. SPDX-License-Identifier: GPL-2.0
+
+======================================================
+cdc_mbim - Driver for CDC MBIM Mobile Broadband modems
+======================================================
+
+The cdc_mbim driver supports USB devices conforming to the "Universal
+Serial Bus Communications Class Subclass Specification for Mobile
+Broadband Interface Model" [1], which is a further development of
+"Universal Serial Bus Communications Class Subclass Specifications for
+Network Control Model Devices" [2] optimized for Mobile Broadband
+devices, aka "3G/LTE modems".
+
+
+Command Line Parameters
+=======================
+
+The cdc_mbim driver has no parameters of its own. But the probing
+behaviour for NCM 1.0 backwards compatible MBIM functions (an
+"NCM/MBIM function" as defined in section 3.2 of [1]) is affected
+by a cdc_ncm driver parameter:
+
+prefer_mbim
+-----------
+:Type: Boolean
+:Valid Range: N/Y (0-1)
+:Default Value: Y (MBIM is preferred)
+
+This parameter sets the system policy for NCM/MBIM functions. Such
+functions will be handled by either the cdc_ncm driver or the cdc_mbim
+driver depending on the prefer_mbim setting. Setting prefer_mbim=N
+makes the cdc_mbim driver ignore these functions and lets the cdc_ncm
+driver handle them instead.
+
+The parameter is writable, and can be changed at any time. A manual
+unbind/bind is required to make the change effective for NCM/MBIM
+functions bound to the "wrong" driver
+
+
+Basic usage
+===========
+
+MBIM functions are inactive when unmanaged. The cdc_mbim driver only
+provides a userspace interface to the MBIM control channel, and will
+not participate in the management of the function. This implies that a
+userspace MBIM management application always is required to enable a
+MBIM function.
+
+Such userspace applications includes, but are not limited to:
+
+ - mbimcli (included with the libmbim [3] library), and
+ - ModemManager [4]
+
+Establishing a MBIM IP session reequires at least these actions by the
+management application:
+
+ - open the control channel
+ - configure network connection settings
+ - connect to network
+ - configure IP interface
+
+Management application development
+----------------------------------
+The driver <-> userspace interfaces are described below. The MBIM
+control channel protocol is described in [1].
+
+
+MBIM control channel userspace ABI
+==================================
+
+/dev/cdc-wdmX character device
+------------------------------
+The driver creates a two-way pipe to the MBIM function control channel
+using the cdc-wdm driver as a subdriver. The userspace end of the
+control channel pipe is a /dev/cdc-wdmX character device.
+
+The cdc_mbim driver does not process or police messages on the control
+channel. The channel is fully delegated to the userspace management
+application. It is therefore up to this application to ensure that it
+complies with all the control channel requirements in [1].
+
+The cdc-wdmX device is created as a child of the MBIM control
+interface USB device. The character device associated with a specific
+MBIM function can be looked up using sysfs. For example::
+
+ bjorn@nemi:~$ ls /sys/bus/usb/drivers/cdc_mbim/2-4:2.12/usbmisc
+ cdc-wdm0
+
+ bjorn@nemi:~$ grep . /sys/bus/usb/drivers/cdc_mbim/2-4:2.12/usbmisc/cdc-wdm0/dev
+ 180:0
+
+
+USB configuration descriptors
+-----------------------------
+The wMaxControlMessage field of the CDC MBIM functional descriptor
+limits the maximum control message size. The management application is
+responsible for negotiating a control message size complying with the
+requirements in section 9.3.1 of [1], taking this descriptor field
+into consideration.
+
+The userspace application can access the CDC MBIM functional
+descriptor of a MBIM function using either of the two USB
+configuration descriptor kernel interfaces described in [6] or [7].
+
+See also the ioctl documentation below.
+
+
+Fragmentation
+-------------
+The userspace application is responsible for all control message
+fragmentation and defragmentaion, as described in section 9.5 of [1].
+
+
+/dev/cdc-wdmX write()
+---------------------
+The MBIM control messages from the management application *must not*
+exceed the negotiated control message size.
+
+
+/dev/cdc-wdmX read()
+--------------------
+The management application *must* accept control messages of up the
+negotiated control message size.
+
+
+/dev/cdc-wdmX ioctl()
+---------------------
+IOCTL_WDM_MAX_COMMAND: Get Maximum Command Size
+This ioctl returns the wMaxControlMessage field of the CDC MBIM
+functional descriptor for MBIM devices. This is intended as a
+convenience, eliminating the need to parse the USB descriptors from
+userspace.
+
+::
+
+ #include <stdio.h>
+ #include <fcntl.h>
+ #include <sys/ioctl.h>
+ #include <linux/types.h>
+ #include <linux/usb/cdc-wdm.h>
+ int main()
+ {
+ __u16 max;
+ int fd = open("/dev/cdc-wdm0", O_RDWR);
+ if (!ioctl(fd, IOCTL_WDM_MAX_COMMAND, &max))
+ printf("wMaxControlMessage is %d\n", max);
+ }
+
+
+Custom device services
+----------------------
+The MBIM specification allows vendors to freely define additional
+services. This is fully supported by the cdc_mbim driver.
+
+Support for new MBIM services, including vendor specified services, is
+implemented entirely in userspace, like the rest of the MBIM control
+protocol
+
+New services should be registered in the MBIM Registry [5].
+
+
+
+MBIM data channel userspace ABI
+===============================
+
+wwanY network device
+--------------------
+The cdc_mbim driver represents the MBIM data channel as a single
+network device of the "wwan" type. This network device is initially
+mapped to MBIM IP session 0.
+
+
+Multiplexed IP sessions (IPS)
+-----------------------------
+MBIM allows multiplexing up to 256 IP sessions over a single USB data
+channel. The cdc_mbim driver models such IP sessions as 802.1q VLAN
+subdevices of the master wwanY device, mapping MBIM IP session Z to
+VLAN ID Z for all values of Z greater than 0.
+
+The device maximum Z is given in the MBIM_DEVICE_CAPS_INFO structure
+described in section 10.5.1 of [1].
+
+The userspace management application is responsible for adding new
+VLAN links prior to establishing MBIM IP sessions where the SessionId
+is greater than 0. These links can be added by using the normal VLAN
+kernel interfaces, either ioctl or netlink.
+
+For example, adding a link for a MBIM IP session with SessionId 3::
+
+ ip link add link wwan0 name wwan0.3 type vlan id 3
+
+The driver will automatically map the "wwan0.3" network device to MBIM
+IP session 3.
+
+
+Device Service Streams (DSS)
+----------------------------
+MBIM also allows up to 256 non-IP data streams to be multiplexed over
+the same shared USB data channel. The cdc_mbim driver models these
+sessions as another set of 802.1q VLAN subdevices of the master wwanY
+device, mapping MBIM DSS session A to VLAN ID (256 + A) for all values
+of A.
+
+The device maximum A is given in the MBIM_DEVICE_SERVICES_INFO
+structure described in section 10.5.29 of [1].
+
+The DSS VLAN subdevices are used as a practical interface between the
+shared MBIM data channel and a MBIM DSS aware userspace application.
+It is not intended to be presented as-is to an end user. The
+assumption is that a userspace application initiating a DSS session
+also takes care of the necessary framing of the DSS data, presenting
+the stream to the end user in an appropriate way for the stream type.
+
+The network device ABI requires a dummy ethernet header for every DSS
+data frame being transported. The contents of this header is
+arbitrary, with the following exceptions:
+
+ - TX frames using an IP protocol (0x0800 or 0x86dd) will be dropped
+ - RX frames will have the protocol field set to ETH_P_802_3 (but will
+ not be properly formatted 802.3 frames)
+ - RX frames will have the destination address set to the hardware
+ address of the master device
+
+The DSS supporting userspace management application is responsible for
+adding the dummy ethernet header on TX and stripping it on RX.
+
+This is a simple example using tools commonly available, exporting
+DssSessionId 5 as a pty character device pointed to by a /dev/nmea
+symlink::
+
+ ip link add link wwan0 name wwan0.dss5 type vlan id 261
+ ip link set dev wwan0.dss5 up
+ socat INTERFACE:wwan0.dss5,type=2 PTY:,echo=0,link=/dev/nmea
+
+This is only an example, most suitable for testing out a DSS
+service. Userspace applications supporting specific MBIM DSS services
+are expected to use the tools and programming interfaces required by
+that service.
+
+Note that adding VLAN links for DSS sessions is entirely optional. A
+management application may instead choose to bind a packet socket
+directly to the master network device, using the received VLAN tags to
+map frames to the correct DSS session and adding 18 byte VLAN ethernet
+headers with the appropriate tag on TX. In this case using a socket
+filter is recommended, matching only the DSS VLAN subset. This avoid
+unnecessary copying of unrelated IP session data to userspace. For
+example::
+
+ static struct sock_filter dssfilter[] = {
+ /* use special negative offsets to get VLAN tag */
+ BPF_STMT(BPF_LD|BPF_B|BPF_ABS, SKF_AD_OFF + SKF_AD_VLAN_TAG_PRESENT),
+ BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, 1, 0, 6), /* true */
+
+ /* verify DSS VLAN range */
+ BPF_STMT(BPF_LD|BPF_H|BPF_ABS, SKF_AD_OFF + SKF_AD_VLAN_TAG),
+ BPF_JUMP(BPF_JMP|BPF_JGE|BPF_K, 256, 0, 4), /* 256 is first DSS VLAN */
+ BPF_JUMP(BPF_JMP|BPF_JGE|BPF_K, 512, 3, 0), /* 511 is last DSS VLAN */
+
+ /* verify ethertype */
+ BPF_STMT(BPF_LD|BPF_H|BPF_ABS, 2 * ETH_ALEN),
+ BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, ETH_P_802_3, 0, 1),
+
+ BPF_STMT(BPF_RET|BPF_K, (u_int)-1), /* accept */
+ BPF_STMT(BPF_RET|BPF_K, 0), /* ignore */
+ };
+
+
+
+Tagged IP session 0 VLAN
+------------------------
+As described above, MBIM IP session 0 is treated as special by the
+driver. It is initially mapped to untagged frames on the wwanY
+network device.
+
+This mapping implies a few restrictions on multiplexed IPS and DSS
+sessions, which may not always be practical:
+
+ - no IPS or DSS session can use a frame size greater than the MTU on
+ IP session 0
+ - no IPS or DSS session can be in the up state unless the network
+ device representing IP session 0 also is up
+
+These problems can be avoided by optionally making the driver map IP
+session 0 to a VLAN subdevice, similar to all other IP sessions. This
+behaviour is triggered by adding a VLAN link for the magic VLAN ID
+4094. The driver will then immediately start mapping MBIM IP session
+0 to this VLAN, and will drop untagged frames on the master wwanY
+device.
+
+Tip: It might be less confusing to the end user to name this VLAN
+subdevice after the MBIM SessionID instead of the VLAN ID. For
+example::
+
+ ip link add link wwan0 name wwan0.0 type vlan id 4094
+
+
+VLAN mapping
+------------
+
+Summarizing the cdc_mbim driver mapping described above, we have this
+relationship between VLAN tags on the wwanY network device and MBIM
+sessions on the shared USB data channel::
+
+ VLAN ID MBIM type MBIM SessionID Notes
+ ---------------------------------------------------------
+ untagged IPS 0 a)
+ 1 - 255 IPS 1 - 255 <VLANID>
+ 256 - 511 DSS 0 - 255 <VLANID - 256>
+ 512 - 4093 b)
+ 4094 IPS 0 c)
+
+ a) if no VLAN ID 4094 link exists, else dropped
+ b) unsupported VLAN range, unconditionally dropped
+ c) if a VLAN ID 4094 link exists, else dropped
+
+
+
+
+References
+==========
+
+ 1) USB Implementers Forum, Inc. - "Universal Serial Bus
+ Communications Class Subclass Specification for Mobile Broadband
+ Interface Model", Revision 1.0 (Errata 1), May 1, 2013
+
+ - http://www.usb.org/developers/docs/devclass_docs/
+
+ 2) USB Implementers Forum, Inc. - "Universal Serial Bus
+ Communications Class Subclass Specifications for Network Control
+ Model Devices", Revision 1.0 (Errata 1), November 24, 2010
+
+ - http://www.usb.org/developers/docs/devclass_docs/
+
+ 3) libmbim - "a glib-based library for talking to WWAN modems and
+ devices which speak the Mobile Interface Broadband Model (MBIM)
+ protocol"
+
+ - http://www.freedesktop.org/wiki/Software/libmbim/
+
+ 4) ModemManager - "a DBus-activated daemon which controls mobile
+ broadband (2G/3G/4G) devices and connections"
+
+ - http://www.freedesktop.org/wiki/Software/ModemManager/
+
+ 5) "MBIM (Mobile Broadband Interface Model) Registry"
+
+ - http://compliance.usb.org/mbim/
+
+ 6) "/sys/kernel/debug/usb/devices output format"
+
+ - Documentation/driver-api/usb/usb.rst
+
+ 7) "/sys/bus/usb/devices/.../descriptors"
+
+ - Documentation/ABI/stable/sysfs-bus-usb