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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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+=============
+uinput module
+=============
+
+Introduction
+============
+
+uinput is a kernel module that makes it possible to emulate input devices
+from userspace. By writing to /dev/uinput (or /dev/input/uinput) device, a
+process can create a virtual input device with specific capabilities. Once
+this virtual device is created, the process can send events through it,
+that will be delivered to userspace and in-kernel consumers.
+
+Interface
+=========
+
+::
+
+ linux/uinput.h
+
+The uinput header defines ioctls to create, set up, and destroy virtual
+devices.
+
+libevdev
+========
+
+libevdev is a wrapper library for evdev devices that provides interfaces to
+create uinput devices and send events. libevdev is less error-prone than
+accessing uinput directly, and should be considered for new software.
+
+For examples and more information about libevdev:
+https://www.freedesktop.org/software/libevdev/doc/latest/
+
+Examples
+========
+
+Keyboard events
+---------------
+
+This first example shows how to create a new virtual device, and how to
+send a key event. All default imports and error handlers were removed for
+the sake of simplicity.
+
+.. code-block:: c
+
+ #include <linux/uinput.h>
+
+ void emit(int fd, int type, int code, int val)
+ {
+ struct input_event ie;
+
+ ie.type = type;
+ ie.code = code;
+ ie.value = val;
+ /* timestamp values below are ignored */
+ ie.time.tv_sec = 0;
+ ie.time.tv_usec = 0;
+
+ write(fd, &ie, sizeof(ie));
+ }
+
+ int main(void)
+ {
+ struct uinput_setup usetup;
+
+ int fd = open("/dev/uinput", O_WRONLY | O_NONBLOCK);
+
+
+ /*
+ * The ioctls below will enable the device that is about to be
+ * created, to pass key events, in this case the space key.
+ */
+ ioctl(fd, UI_SET_EVBIT, EV_KEY);
+ ioctl(fd, UI_SET_KEYBIT, KEY_SPACE);
+
+ memset(&usetup, 0, sizeof(usetup));
+ usetup.id.bustype = BUS_USB;
+ usetup.id.vendor = 0x1234; /* sample vendor */
+ usetup.id.product = 0x5678; /* sample product */
+ strcpy(usetup.name, "Example device");
+
+ ioctl(fd, UI_DEV_SETUP, &usetup);
+ ioctl(fd, UI_DEV_CREATE);
+
+ /*
+ * On UI_DEV_CREATE the kernel will create the device node for this
+ * device. We are inserting a pause here so that userspace has time
+ * to detect, initialize the new device, and can start listening to
+ * the event, otherwise it will not notice the event we are about
+ * to send. This pause is only needed in our example code!
+ */
+ sleep(1);
+
+ /* Key press, report the event, send key release, and report again */
+ emit(fd, EV_KEY, KEY_SPACE, 1);
+ emit(fd, EV_SYN, SYN_REPORT, 0);
+ emit(fd, EV_KEY, KEY_SPACE, 0);
+ emit(fd, EV_SYN, SYN_REPORT, 0);
+
+ /*
+ * Give userspace some time to read the events before we destroy the
+ * device with UI_DEV_DESTROY.
+ */
+ sleep(1);
+
+ ioctl(fd, UI_DEV_DESTROY);
+ close(fd);
+
+ return 0;
+ }
+
+Mouse movements
+---------------
+
+This example shows how to create a virtual device that behaves like a physical
+mouse.
+
+.. code-block:: c
+
+ #include <linux/uinput.h>
+
+ /* emit function is identical to of the first example */
+
+ int main(void)
+ {
+ struct uinput_setup usetup;
+ int i = 50;
+
+ int fd = open("/dev/uinput", O_WRONLY | O_NONBLOCK);
+
+ /* enable mouse button left and relative events */
+ ioctl(fd, UI_SET_EVBIT, EV_KEY);
+ ioctl(fd, UI_SET_KEYBIT, BTN_LEFT);
+
+ ioctl(fd, UI_SET_EVBIT, EV_REL);
+ ioctl(fd, UI_SET_RELBIT, REL_X);
+ ioctl(fd, UI_SET_RELBIT, REL_Y);
+
+ memset(&usetup, 0, sizeof(usetup));
+ usetup.id.bustype = BUS_USB;
+ usetup.id.vendor = 0x1234; /* sample vendor */
+ usetup.id.product = 0x5678; /* sample product */
+ strcpy(usetup.name, "Example device");
+
+ ioctl(fd, UI_DEV_SETUP, &usetup);
+ ioctl(fd, UI_DEV_CREATE);
+
+ /*
+ * On UI_DEV_CREATE the kernel will create the device node for this
+ * device. We are inserting a pause here so that userspace has time
+ * to detect, initialize the new device, and can start listening to
+ * the event, otherwise it will not notice the event we are about
+ * to send. This pause is only needed in our example code!
+ */
+ sleep(1);
+
+ /* Move the mouse diagonally, 5 units per axis */
+ while (i--) {
+ emit(fd, EV_REL, REL_X, 5);
+ emit(fd, EV_REL, REL_Y, 5);
+ emit(fd, EV_SYN, SYN_REPORT, 0);
+ usleep(15000);
+ }
+
+ /*
+ * Give userspace some time to read the events before we destroy the
+ * device with UI_DEV_DESTROY.
+ */
+ sleep(1);
+
+ ioctl(fd, UI_DEV_DESTROY);
+ close(fd);
+
+ return 0;
+ }
+
+
+uinput old interface
+--------------------
+
+Before uinput version 5, there wasn't a dedicated ioctl to set up a virtual
+device. Programs supporting older versions of uinput interface need to fill
+a uinput_user_dev structure and write it to the uinput file descriptor to
+configure the new uinput device. New code should not use the old interface
+but interact with uinput via ioctl calls, or use libevdev.
+
+.. code-block:: c
+
+ #include <linux/uinput.h>
+
+ /* emit function is identical to of the first example */
+
+ int main(void)
+ {
+ struct uinput_user_dev uud;
+ int version, rc, fd;
+
+ fd = open("/dev/uinput", O_WRONLY | O_NONBLOCK);
+ rc = ioctl(fd, UI_GET_VERSION, &version);
+
+ if (rc == 0 && version >= 5) {
+ /* use UI_DEV_SETUP */
+ return 0;
+ }
+
+ /*
+ * The ioctls below will enable the device that is about to be
+ * created, to pass key events, in this case the space key.
+ */
+ ioctl(fd, UI_SET_EVBIT, EV_KEY);
+ ioctl(fd, UI_SET_KEYBIT, KEY_SPACE);
+
+ memset(&uud, 0, sizeof(uud));
+ snprintf(uud.name, UINPUT_MAX_NAME_SIZE, "uinput old interface");
+ write(fd, &uud, sizeof(uud));
+
+ ioctl(fd, UI_DEV_CREATE);
+
+ /*
+ * On UI_DEV_CREATE the kernel will create the device node for this
+ * device. We are inserting a pause here so that userspace has time
+ * to detect, initialize the new device, and can start listening to
+ * the event, otherwise it will not notice the event we are about
+ * to send. This pause is only needed in our example code!
+ */
+ sleep(1);
+
+ /* Key press, report the event, send key release, and report again */
+ emit(fd, EV_KEY, KEY_SPACE, 1);
+ emit(fd, EV_SYN, SYN_REPORT, 0);
+ emit(fd, EV_KEY, KEY_SPACE, 0);
+ emit(fd, EV_SYN, SYN_REPORT, 0);
+
+ /*
+ * Give userspace some time to read the events before we destroy the
+ * device with UI_DEV_DESTROY.
+ */
+ sleep(1);
+
+ ioctl(fd, UI_DEV_DESTROY);
+
+ close(fd);
+ return 0;
+ }
+