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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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+.. _usb-urb:
+
+USB Request Block (URB)
+~~~~~~~~~~~~~~~~~~~~~~~
+
+:Revised: 2000-Dec-05
+:Again: 2002-Jul-06
+:Again: 2005-Sep-19
+:Again: 2017-Mar-29
+
+
+.. note::
+
+ The USB subsystem now has a substantial section at :ref:`usb-hostside-api`
+ section, generated from the current source code.
+ This particular documentation file isn't complete and may not be
+ updated to the last version; don't rely on it except for a quick
+ overview.
+
+Basic concept or 'What is an URB?'
+==================================
+
+The basic idea of the new driver is message passing, the message itself is
+called USB Request Block, or URB for short.
+
+- An URB consists of all relevant information to execute any USB transaction
+ and deliver the data and status back.
+
+- Execution of an URB is inherently an asynchronous operation, i.e. the
+ :c:func:`usb_submit_urb` call returns immediately after it has successfully
+ queued the requested action.
+
+- Transfers for one URB can be canceled with :c:func:`usb_unlink_urb`
+ at any time.
+
+- Each URB has a completion handler, which is called after the action
+ has been successfully completed or canceled. The URB also contains a
+ context-pointer for passing information to the completion handler.
+
+- Each endpoint for a device logically supports a queue of requests.
+ You can fill that queue, so that the USB hardware can still transfer
+ data to an endpoint while your driver handles completion of another.
+ This maximizes use of USB bandwidth, and supports seamless streaming
+ of data to (or from) devices when using periodic transfer modes.
+
+
+The URB structure
+=================
+
+Some of the fields in struct urb are::
+
+ struct urb
+ {
+ // (IN) device and pipe specify the endpoint queue
+ struct usb_device *dev; // pointer to associated USB device
+ unsigned int pipe; // endpoint information
+
+ unsigned int transfer_flags; // URB_ISO_ASAP, URB_SHORT_NOT_OK, etc.
+
+ // (IN) all urbs need completion routines
+ void *context; // context for completion routine
+ usb_complete_t complete; // pointer to completion routine
+
+ // (OUT) status after each completion
+ int status; // returned status
+
+ // (IN) buffer used for data transfers
+ void *transfer_buffer; // associated data buffer
+ u32 transfer_buffer_length; // data buffer length
+ int number_of_packets; // size of iso_frame_desc
+
+ // (OUT) sometimes only part of CTRL/BULK/INTR transfer_buffer is used
+ u32 actual_length; // actual data buffer length
+
+ // (IN) setup stage for CTRL (pass a struct usb_ctrlrequest)
+ unsigned char *setup_packet; // setup packet (control only)
+
+ // Only for PERIODIC transfers (ISO, INTERRUPT)
+ // (IN/OUT) start_frame is set unless URB_ISO_ASAP isn't set
+ int start_frame; // start frame
+ int interval; // polling interval
+
+ // ISO only: packets are only "best effort"; each can have errors
+ int error_count; // number of errors
+ struct usb_iso_packet_descriptor iso_frame_desc[0];
+ };
+
+Your driver must create the "pipe" value using values from the appropriate
+endpoint descriptor in an interface that it's claimed.
+
+
+How to get an URB?
+==================
+
+URBs are allocated by calling :c:func:`usb_alloc_urb`::
+
+ struct urb *usb_alloc_urb(int isoframes, int mem_flags)
+
+Return value is a pointer to the allocated URB, 0 if allocation failed.
+The parameter isoframes specifies the number of isochronous transfer frames
+you want to schedule. For CTRL/BULK/INT, use 0. The mem_flags parameter
+holds standard memory allocation flags, letting you control (among other
+things) whether the underlying code may block or not.
+
+To free an URB, use :c:func:`usb_free_urb`::
+
+ void usb_free_urb(struct urb *urb)
+
+You may free an urb that you've submitted, but which hasn't yet been
+returned to you in a completion callback. It will automatically be
+deallocated when it is no longer in use.
+
+
+What has to be filled in?
+=========================
+
+Depending on the type of transaction, there are some inline functions
+defined in ``linux/usb.h`` to simplify the initialization, such as
+:c:func:`usb_fill_control_urb`, :c:func:`usb_fill_bulk_urb` and
+:c:func:`usb_fill_int_urb`. In general, they need the usb device pointer,
+the pipe (usual format from usb.h), the transfer buffer, the desired transfer
+length, the completion handler, and its context. Take a look at the some
+existing drivers to see how they're used.
+
+Flags:
+
+- For ISO there are two startup behaviors: Specified start_frame or ASAP.
+- For ASAP set ``URB_ISO_ASAP`` in transfer_flags.
+
+If short packets should NOT be tolerated, set ``URB_SHORT_NOT_OK`` in
+transfer_flags.
+
+
+How to submit an URB?
+=====================
+
+Just call :c:func:`usb_submit_urb`::
+
+ int usb_submit_urb(struct urb *urb, int mem_flags)
+
+The ``mem_flags`` parameter, such as ``GFP_ATOMIC``, controls memory
+allocation, such as whether the lower levels may block when memory is tight.
+
+It immediately returns, either with status 0 (request queued) or some
+error code, usually caused by the following:
+
+- Out of memory (``-ENOMEM``)
+- Unplugged device (``-ENODEV``)
+- Stalled endpoint (``-EPIPE``)
+- Too many queued ISO transfers (``-EAGAIN``)
+- Too many requested ISO frames (``-EFBIG``)
+- Invalid INT interval (``-EINVAL``)
+- More than one packet for INT (``-EINVAL``)
+
+After submission, ``urb->status`` is ``-EINPROGRESS``; however, you should
+never look at that value except in your completion callback.
+
+For isochronous endpoints, your completion handlers should (re)submit
+URBs to the same endpoint with the ``URB_ISO_ASAP`` flag, using
+multi-buffering, to get seamless ISO streaming.
+
+
+How to cancel an already running URB?
+=====================================
+
+There are two ways to cancel an URB you've submitted but which hasn't
+been returned to your driver yet. For an asynchronous cancel, call
+:c:func:`usb_unlink_urb`::
+
+ int usb_unlink_urb(struct urb *urb)
+
+It removes the urb from the internal list and frees all allocated
+HW descriptors. The status is changed to reflect unlinking. Note
+that the URB will not normally have finished when :c:func:`usb_unlink_urb`
+returns; you must still wait for the completion handler to be called.
+
+To cancel an URB synchronously, call :c:func:`usb_kill_urb`::
+
+ void usb_kill_urb(struct urb *urb)
+
+It does everything :c:func:`usb_unlink_urb` does, and in addition it waits
+until after the URB has been returned and the completion handler
+has finished. It also marks the URB as temporarily unusable, so
+that if the completion handler or anyone else tries to resubmit it
+they will get a ``-EPERM`` error. Thus you can be sure that when
+:c:func:`usb_kill_urb` returns, the URB is totally idle.
+
+There is a lifetime issue to consider. An URB may complete at any
+time, and the completion handler may free the URB. If this happens
+while :c:func:`usb_unlink_urb` or :c:func:`usb_kill_urb` is running, it will
+cause a memory-access violation. The driver is responsible for avoiding this,
+which often means some sort of lock will be needed to prevent the URB
+from being deallocated while it is still in use.
+
+On the other hand, since usb_unlink_urb may end up calling the
+completion handler, the handler must not take any lock that is held
+when usb_unlink_urb is invoked. The general solution to this problem
+is to increment the URB's reference count while holding the lock, then
+drop the lock and call usb_unlink_urb or usb_kill_urb, and then
+decrement the URB's reference count. You increment the reference
+count by calling :c:func`usb_get_urb`::
+
+ struct urb *usb_get_urb(struct urb *urb)
+
+(ignore the return value; it is the same as the argument) and
+decrement the reference count by calling :c:func:`usb_free_urb`. Of course,
+none of this is necessary if there's no danger of the URB being freed
+by the completion handler.
+
+
+What about the completion handler?
+==================================
+
+The handler is of the following type::
+
+ typedef void (*usb_complete_t)(struct urb *)
+
+I.e., it gets the URB that caused the completion call. In the completion
+handler, you should have a look at ``urb->status`` to detect any USB errors.
+Since the context parameter is included in the URB, you can pass
+information to the completion handler.
+
+Note that even when an error (or unlink) is reported, data may have been
+transferred. That's because USB transfers are packetized; it might take
+sixteen packets to transfer your 1KByte buffer, and ten of them might
+have transferred successfully before the completion was called.
+
+
+.. warning::
+
+ NEVER SLEEP IN A COMPLETION HANDLER.
+
+ These are often called in atomic context.
+
+In the current kernel, completion handlers run with local interrupts
+disabled, but in the future this will be changed, so don't assume that
+local IRQs are always disabled inside completion handlers.
+
+How to do isochronous (ISO) transfers?
+======================================
+
+Besides the fields present on a bulk transfer, for ISO, you also
+have to set ``urb->interval`` to say how often to make transfers; it's
+often one per frame (which is once every microframe for highspeed devices).
+The actual interval used will be a power of two that's no bigger than what
+you specify. You can use the :c:func:`usb_fill_int_urb` macro to fill
+most ISO transfer fields.
+
+For ISO transfers you also have to fill a :c:type:`usb_iso_packet_descriptor`
+structure, allocated at the end of the URB by :c:func:`usb_alloc_urb`, for
+each packet you want to schedule.
+
+The :c:func:`usb_submit_urb` call modifies ``urb->interval`` to the implemented
+interval value that is less than or equal to the requested interval value. If
+``URB_ISO_ASAP`` scheduling is used, ``urb->start_frame`` is also updated.
+
+For each entry you have to specify the data offset for this frame (base is
+transfer_buffer), and the length you want to write/expect to read.
+After completion, actual_length contains the actual transferred length and
+status contains the resulting status for the ISO transfer for this frame.
+It is allowed to specify a varying length from frame to frame (e.g. for
+audio synchronisation/adaptive transfer rates). You can also use the length
+0 to omit one or more frames (striping).
+
+For scheduling you can choose your own start frame or ``URB_ISO_ASAP``. As
+explained earlier, if you always keep at least one URB queued and your
+completion keeps (re)submitting a later URB, you'll get smooth ISO streaming
+(if usb bandwidth utilization allows).
+
+If you specify your own start frame, make sure it's several frames in advance
+of the current frame. You might want this model if you're synchronizing
+ISO data with some other event stream.
+
+
+How to start interrupt (INT) transfers?
+=======================================
+
+Interrupt transfers, like isochronous transfers, are periodic, and happen
+in intervals that are powers of two (1, 2, 4 etc) units. Units are frames
+for full and low speed devices, and microframes for high speed ones.
+You can use the :c:func:`usb_fill_int_urb` macro to fill INT transfer fields.
+
+The :c:func:`usb_submit_urb` call modifies ``urb->interval`` to the implemented
+interval value that is less than or equal to the requested interval value.
+
+In Linux 2.6, unlike earlier versions, interrupt URBs are not automagically
+restarted when they complete. They end when the completion handler is
+called, just like other URBs. If you want an interrupt URB to be restarted,
+your completion handler must resubmit it.
+s