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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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+~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+Programming gameport drivers
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+A basic classic gameport
+~~~~~~~~~~~~~~~~~~~~~~~~
+
+If the gameport doesn't provide more than the inb()/outb() functionality,
+the code needed to register it with the joystick drivers is simple::
+
+ struct gameport gameport;
+
+ gameport.io = MY_IO_ADDRESS;
+ gameport_register_port(&gameport);
+
+Make sure struct gameport is initialized to 0 in all other fields. The
+gameport generic code will take care of the rest.
+
+If your hardware supports more than one io address, and your driver can
+choose which one to program the hardware to, starting from the more exotic
+addresses is preferred, because the likelihood of clashing with the standard
+0x201 address is smaller.
+
+E.g. if your driver supports addresses 0x200, 0x208, 0x210 and 0x218, then
+0x218 would be the address of first choice.
+
+If your hardware supports a gameport address that is not mapped to ISA io
+space (is above 0x1000), use that one, and don't map the ISA mirror.
+
+Also, always request_region() on the whole io space occupied by the
+gameport. Although only one ioport is really used, the gameport usually
+occupies from one to sixteen addresses in the io space.
+
+Please also consider enabling the gameport on the card in the ->open()
+callback if the io is mapped to ISA space - this way it'll occupy the io
+space only when something really is using it. Disable it again in the
+->close() callback. You also can select the io address in the ->open()
+callback, so that it doesn't fail if some of the possible addresses are
+already occupied by other gameports.
+
+Memory mapped gameport
+~~~~~~~~~~~~~~~~~~~~~~
+
+When a gameport can be accessed through MMIO, this way is preferred, because
+it is faster, allowing more reads per second. Registering such a gameport
+isn't as easy as a basic IO one, but not so much complex::
+
+ struct gameport gameport;
+
+ void my_trigger(struct gameport *gameport)
+ {
+ my_mmio = 0xff;
+ }
+
+ unsigned char my_read(struct gameport *gameport)
+ {
+ return my_mmio;
+ }
+
+ gameport.read = my_read;
+ gameport.trigger = my_trigger;
+ gameport_register_port(&gameport);
+
+.. _gameport_pgm_cooked_mode:
+
+Cooked mode gameport
+~~~~~~~~~~~~~~~~~~~~
+
+There are gameports that can report the axis values as numbers, that means
+the driver doesn't have to measure them the old way - an ADC is built into
+the gameport. To register a cooked gameport::
+
+ struct gameport gameport;
+
+ int my_cooked_read(struct gameport *gameport, int *axes, int *buttons)
+ {
+ int i;
+
+ for (i = 0; i < 4; i++)
+ axes[i] = my_mmio[i];
+ buttons[0] = my_mmio[4];
+ }
+
+ int my_open(struct gameport *gameport, int mode)
+ {
+ return -(mode != GAMEPORT_MODE_COOKED);
+ }
+
+ gameport.cooked_read = my_cooked_read;
+ gameport.open = my_open;
+ gameport.fuzz = 8;
+ gameport_register_port(&gameport);
+
+The only confusing thing here is the fuzz value. Best determined by
+experimentation, it is the amount of noise in the ADC data. Perfect
+gameports can set this to zero, most common have fuzz between 8 and 32.
+See analog.c and input.c for handling of fuzz - the fuzz value determines
+the size of a gaussian filter window that is used to eliminate the noise
+in the data.
+
+More complex gameports
+~~~~~~~~~~~~~~~~~~~~~~
+
+Gameports can support both raw and cooked modes. In that case combine either
+examples 1+2 or 1+3. Gameports can support internal calibration - see below,
+and also lightning.c and analog.c on how that works. If your driver supports
+more than one gameport instance simultaneously, use the ->private member of
+the gameport struct to point to your data.
+
+Unregistering a gameport
+~~~~~~~~~~~~~~~~~~~~~~~~
+
+Simple::
+
+ gameport_unregister_port(&gameport);
+
+The gameport structure
+~~~~~~~~~~~~~~~~~~~~~~
+
+::
+
+ struct gameport {
+
+ void *port_data;
+
+A private pointer for free use in the gameport driver. (Not the joystick
+driver!)
+
+::
+
+ char name[32];
+
+Driver's name as set by driver calling gameport_set_name(). Informational
+purpose only.
+
+::
+
+ char phys[32];
+
+gameport's physical name/description as set by driver calling gameport_set_phys().
+Informational purpose only.
+
+::
+
+ int io;
+
+I/O address for use with raw mode. You have to either set this, or ->read()
+to some value if your gameport supports raw mode.
+
+::
+
+ int speed;
+
+Raw mode speed of the gameport reads in thousands of reads per second.
+
+::
+
+ int fuzz;
+
+If the gameport supports cooked mode, this should be set to a value that
+represents the amount of noise in the data. See
+:ref:`gameport_pgm_cooked_mode`.
+
+::
+
+ void (*trigger)(struct gameport *);
+
+Trigger. This function should trigger the ns558 oneshots. If set to NULL,
+outb(0xff, io) will be used.
+
+::
+
+ unsigned char (*read)(struct gameport *);
+
+Read the buttons and ns558 oneshot bits. If set to NULL, inb(io) will be
+used instead.
+
+::
+
+ int (*cooked_read)(struct gameport *, int *axes, int *buttons);
+
+If the gameport supports cooked mode, it should point this to its cooked
+read function. It should fill axes[0..3] with four values of the joystick axes
+and buttons[0] with four bits representing the buttons.
+
+::
+
+ int (*calibrate)(struct gameport *, int *axes, int *max);
+
+Function for calibrating the ADC hardware. When called, axes[0..3] should be
+pre-filled by cooked data by the caller, max[0..3] should be pre-filled with
+expected maximums for each axis. The calibrate() function should set the
+sensitivity of the ADC hardware so that the maximums fit in its range and
+recompute the axes[] values to match the new sensitivity or re-read them from
+the hardware so that they give valid values.
+
+::
+
+ int (*open)(struct gameport *, int mode);
+
+Open() serves two purposes. First a driver either opens the port in raw or
+in cooked mode, the open() callback can decide which modes are supported.
+Second, resource allocation can happen here. The port can also be enabled
+here. Prior to this call, other fields of the gameport struct (namely the io
+member) need not to be valid.
+
+::
+
+ void (*close)(struct gameport *);
+
+Close() should free the resources allocated by open, possibly disabling the
+gameport.
+
+::
+
+ struct timer_list poll_timer;
+ unsigned int poll_interval; /* in msecs */
+ spinlock_t timer_lock;
+ unsigned int poll_cnt;
+ void (*poll_handler)(struct gameport *);
+ struct gameport *parent, *child;
+ struct gameport_driver *drv;
+ struct mutex drv_mutex; /* protects serio->drv so attributes can pin driver */
+ struct device dev;
+ struct list_head node;
+
+For internal use by the gameport layer.
+
+::
+
+ };
+
+Enjoy!