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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-only
+.. Copyright (C) 2020 Google LLC.
+
+===========================
+BPF_MAP_TYPE_CGROUP_STORAGE
+===========================
+
+The ``BPF_MAP_TYPE_CGROUP_STORAGE`` map type represents a local fix-sized
+storage. It is only available with ``CONFIG_CGROUP_BPF``, and to programs that
+attach to cgroups; the programs are made available by the same Kconfig. The
+storage is identified by the cgroup the program is attached to.
+
+The map provide a local storage at the cgroup that the BPF program is attached
+to. It provides a faster and simpler access than the general purpose hash
+table, which performs a hash table lookups, and requires user to track live
+cgroups on their own.
+
+This document describes the usage and semantics of the
+``BPF_MAP_TYPE_CGROUP_STORAGE`` map type. Some of its behaviors was changed in
+Linux 5.9 and this document will describe the differences.
+
+Usage
+=====
+
+The map uses key of type of either ``__u64 cgroup_inode_id`` or
+``struct bpf_cgroup_storage_key``, declared in ``linux/bpf.h``::
+
+ struct bpf_cgroup_storage_key {
+ __u64 cgroup_inode_id;
+ __u32 attach_type;
+ };
+
+``cgroup_inode_id`` is the inode id of the cgroup directory.
+``attach_type`` is the program's attach type.
+
+Linux 5.9 added support for type ``__u64 cgroup_inode_id`` as the key type.
+When this key type is used, then all attach types of the particular cgroup and
+map will share the same storage. Otherwise, if the type is
+``struct bpf_cgroup_storage_key``, then programs of different attach types
+be isolated and see different storages.
+
+To access the storage in a program, use ``bpf_get_local_storage``::
+
+ void *bpf_get_local_storage(void *map, u64 flags)
+
+``flags`` is reserved for future use and must be 0.
+
+There is no implicit synchronization. Storages of ``BPF_MAP_TYPE_CGROUP_STORAGE``
+can be accessed by multiple programs across different CPUs, and user should
+take care of synchronization by themselves. The bpf infrastructure provides
+``struct bpf_spin_lock`` to synchronize the storage. See
+``tools/testing/selftests/bpf/progs/test_spin_lock.c``.
+
+Examples
+========
+
+Usage with key type as ``struct bpf_cgroup_storage_key``::
+
+ #include <bpf/bpf.h>
+
+ struct {
+ __uint(type, BPF_MAP_TYPE_CGROUP_STORAGE);
+ __type(key, struct bpf_cgroup_storage_key);
+ __type(value, __u32);
+ } cgroup_storage SEC(".maps");
+
+ int program(struct __sk_buff *skb)
+ {
+ __u32 *ptr = bpf_get_local_storage(&cgroup_storage, 0);
+ __sync_fetch_and_add(ptr, 1);
+
+ return 0;
+ }
+
+Userspace accessing map declared above::
+
+ #include <linux/bpf.h>
+ #include <linux/libbpf.h>
+
+ __u32 map_lookup(struct bpf_map *map, __u64 cgrp, enum bpf_attach_type type)
+ {
+ struct bpf_cgroup_storage_key = {
+ .cgroup_inode_id = cgrp,
+ .attach_type = type,
+ };
+ __u32 value;
+ bpf_map_lookup_elem(bpf_map__fd(map), &key, &value);
+ // error checking omitted
+ return value;
+ }
+
+Alternatively, using just ``__u64 cgroup_inode_id`` as key type::
+
+ #include <bpf/bpf.h>
+
+ struct {
+ __uint(type, BPF_MAP_TYPE_CGROUP_STORAGE);
+ __type(key, __u64);
+ __type(value, __u32);
+ } cgroup_storage SEC(".maps");
+
+ int program(struct __sk_buff *skb)
+ {
+ __u32 *ptr = bpf_get_local_storage(&cgroup_storage, 0);
+ __sync_fetch_and_add(ptr, 1);
+
+ return 0;
+ }
+
+And userspace::
+
+ #include <linux/bpf.h>
+ #include <linux/libbpf.h>
+
+ __u32 map_lookup(struct bpf_map *map, __u64 cgrp, enum bpf_attach_type type)
+ {
+ __u32 value;
+ bpf_map_lookup_elem(bpf_map__fd(map), &cgrp, &value);
+ // error checking omitted
+ return value;
+ }
+
+Semantics
+=========
+
+``BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE`` is a variant of this map type. This
+per-CPU variant will have different memory regions for each CPU for each
+storage. The non-per-CPU will have the same memory region for each storage.
+
+Prior to Linux 5.9, the lifetime of a storage is precisely per-attachment, and
+for a single ``CGROUP_STORAGE`` map, there can be at most one program loaded
+that uses the map. A program may be attached to multiple cgroups or have
+multiple attach types, and each attach creates a fresh zeroed storage. The
+storage is freed upon detach.
+
+There is a one-to-one association between the map of each type (per-CPU and
+non-per-CPU) and the BPF program during load verification time. As a result,
+each map can only be used by one BPF program and each BPF program can only use
+one storage map of each type. Because of map can only be used by one BPF
+program, sharing of this cgroup's storage with other BPF programs were
+impossible.
+
+Since Linux 5.9, storage can be shared by multiple programs. When a program is
+attached to a cgroup, the kernel would create a new storage only if the map
+does not already contain an entry for the cgroup and attach type pair, or else
+the old storage is reused for the new attachment. If the map is attach type
+shared, then attach type is simply ignored during comparison. Storage is freed
+only when either the map or the cgroup attached to is being freed. Detaching
+will not directly free the storage, but it may cause the reference to the map
+to reach zero and indirectly freeing all storage in the map.
+
+The map is not associated with any BPF program, thus making sharing possible.
+However, the BPF program can still only associate with one map of each type
+(per-CPU and non-per-CPU). A BPF program cannot use more than one
+``BPF_MAP_TYPE_CGROUP_STORAGE`` or more than one
+``BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE``.
+
+In all versions, userspace may use the attach parameters of cgroup and
+attach type pair in ``struct bpf_cgroup_storage_key`` as the key to the BPF map
+APIs to read or update the storage for a given attachment. For Linux 5.9
+attach type shared storages, only the first value in the struct, cgroup inode
+id, is used during comparison, so userspace may just specify a ``__u64``
+directly.
+
+The storage is bound at attach time. Even if the program is attached to parent
+and triggers in child, the storage still belongs to the parent.
+
+Userspace cannot create a new entry in the map or delete an existing entry.
+Program test runs always use a temporary storage.