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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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+The genalloc/genpool subsystem
+==============================
+
+There are a number of memory-allocation subsystems in the kernel, each
+aimed at a specific need. Sometimes, however, a kernel developer needs to
+implement a new allocator for a specific range of special-purpose memory;
+often that memory is located on a device somewhere. The author of the
+driver for that device can certainly write a little allocator to get the
+job done, but that is the way to fill the kernel with dozens of poorly
+tested allocators. Back in 2005, Jes Sorensen lifted one of those
+allocators from the sym53c8xx_2 driver and posted_ it as a generic module
+for the creation of ad hoc memory allocators. This code was merged
+for the 2.6.13 release; it has been modified considerably since then.
+
+.. _posted: https://lwn.net/Articles/125842/
+
+Code using this allocator should include <linux/genalloc.h>. The action
+begins with the creation of a pool using one of:
+
+.. kernel-doc:: lib/genalloc.c
+ :functions: gen_pool_create
+
+.. kernel-doc:: lib/genalloc.c
+ :functions: devm_gen_pool_create
+
+A call to gen_pool_create() will create a pool. The granularity of
+allocations is set with min_alloc_order; it is a log-base-2 number like
+those used by the page allocator, but it refers to bytes rather than pages.
+So, if min_alloc_order is passed as 3, then all allocations will be a
+multiple of eight bytes. Increasing min_alloc_order decreases the memory
+required to track the memory in the pool. The nid parameter specifies
+which NUMA node should be used for the allocation of the housekeeping
+structures; it can be -1 if the caller doesn't care.
+
+The "managed" interface devm_gen_pool_create() ties the pool to a
+specific device. Among other things, it will automatically clean up the
+pool when the given device is destroyed.
+
+A pool is shut down with:
+
+.. kernel-doc:: lib/genalloc.c
+ :functions: gen_pool_destroy
+
+It's worth noting that, if there are still allocations outstanding from the
+given pool, this function will take the rather extreme step of invoking
+BUG(), crashing the entire system. You have been warned.
+
+A freshly created pool has no memory to allocate. It is fairly useless in
+that state, so one of the first orders of business is usually to add memory
+to the pool. That can be done with one of:
+
+.. kernel-doc:: include/linux/genalloc.h
+ :functions: gen_pool_add
+
+.. kernel-doc:: lib/genalloc.c
+ :functions: gen_pool_add_owner
+
+A call to gen_pool_add() will place the size bytes of memory
+starting at addr (in the kernel's virtual address space) into the given
+pool, once again using nid as the node ID for ancillary memory allocations.
+The gen_pool_add_virt() variant associates an explicit physical
+address with the memory; this is only necessary if the pool will be used
+for DMA allocations.
+
+The functions for allocating memory from the pool (and putting it back)
+are:
+
+.. kernel-doc:: include/linux/genalloc.h
+ :functions: gen_pool_alloc
+
+.. kernel-doc:: lib/genalloc.c
+ :functions: gen_pool_dma_alloc
+
+.. kernel-doc:: lib/genalloc.c
+ :functions: gen_pool_free_owner
+
+As one would expect, gen_pool_alloc() will allocate size< bytes
+from the given pool. The gen_pool_dma_alloc() variant allocates
+memory for use with DMA operations, returning the associated physical
+address in the space pointed to by dma. This will only work if the memory
+was added with gen_pool_add_virt(). Note that this function
+departs from the usual genpool pattern of using unsigned long values to
+represent kernel addresses; it returns a void * instead.
+
+That all seems relatively simple; indeed, some developers clearly found it
+to be too simple. After all, the interface above provides no control over
+how the allocation functions choose which specific piece of memory to
+return. If that sort of control is needed, the following functions will be
+of interest:
+
+.. kernel-doc:: lib/genalloc.c
+ :functions: gen_pool_alloc_algo_owner
+
+.. kernel-doc:: lib/genalloc.c
+ :functions: gen_pool_set_algo
+
+Allocations with gen_pool_alloc_algo() specify an algorithm to be
+used to choose the memory to be allocated; the default algorithm can be set
+with gen_pool_set_algo(). The data value is passed to the
+algorithm; most ignore it, but it is occasionally needed. One can,
+naturally, write a special-purpose algorithm, but there is a fair set
+already available:
+
+- gen_pool_first_fit is a simple first-fit allocator; this is the default
+ algorithm if none other has been specified.
+
+- gen_pool_first_fit_align forces the allocation to have a specific
+ alignment (passed via data in a genpool_data_align structure).
+
+- gen_pool_first_fit_order_align aligns the allocation to the order of the
+ size. A 60-byte allocation will thus be 64-byte aligned, for example.
+
+- gen_pool_best_fit, as one would expect, is a simple best-fit allocator.
+
+- gen_pool_fixed_alloc allocates at a specific offset (passed in a
+ genpool_data_fixed structure via the data parameter) within the pool.
+ If the indicated memory is not available the allocation fails.
+
+There is a handful of other functions, mostly for purposes like querying
+the space available in the pool or iterating through chunks of memory.
+Most users, however, should not need much beyond what has been described
+above. With luck, wider awareness of this module will help to prevent the
+writing of special-purpose memory allocators in the future.
+
+.. kernel-doc:: lib/genalloc.c
+ :functions: gen_pool_virt_to_phys
+
+.. kernel-doc:: lib/genalloc.c
+ :functions: gen_pool_for_each_chunk
+
+.. kernel-doc:: lib/genalloc.c
+ :functions: gen_pool_has_addr
+
+.. kernel-doc:: lib/genalloc.c
+ :functions: gen_pool_avail
+
+.. kernel-doc:: lib/genalloc.c
+ :functions: gen_pool_size
+
+.. kernel-doc:: lib/genalloc.c
+ :functions: gen_pool_get
+
+.. kernel-doc:: lib/genalloc.c
+ :functions: of_gen_pool_get