From 5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Tue, 21 Feb 2023 18:24:12 -0800 Subject: Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next 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(). ... --- lib/klist.c | 407 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 407 insertions(+) create mode 100644 lib/klist.c (limited to 'lib/klist.c') diff --git a/lib/klist.c b/lib/klist.c new file mode 100644 index 000000000..332a4fbf1 --- /dev/null +++ b/lib/klist.c @@ -0,0 +1,407 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * klist.c - Routines for manipulating klists. + * + * Copyright (C) 2005 Patrick Mochel + * + * This klist interface provides a couple of structures that wrap around + * struct list_head to provide explicit list "head" (struct klist) and list + * "node" (struct klist_node) objects. For struct klist, a spinlock is + * included that protects access to the actual list itself. struct + * klist_node provides a pointer to the klist that owns it and a kref + * reference count that indicates the number of current users of that node + * in the list. + * + * The entire point is to provide an interface for iterating over a list + * that is safe and allows for modification of the list during the + * iteration (e.g. insertion and removal), including modification of the + * current node on the list. + * + * It works using a 3rd object type - struct klist_iter - that is declared + * and initialized before an iteration. klist_next() is used to acquire the + * next element in the list. It returns NULL if there are no more items. + * Internally, that routine takes the klist's lock, decrements the + * reference count of the previous klist_node and increments the count of + * the next klist_node. It then drops the lock and returns. + * + * There are primitives for adding and removing nodes to/from a klist. + * When deleting, klist_del() will simply decrement the reference count. + * Only when the count goes to 0 is the node removed from the list. + * klist_remove() will try to delete the node from the list and block until + * it is actually removed. This is useful for objects (like devices) that + * have been removed from the system and must be freed (but must wait until + * all accessors have finished). + */ + +#include +#include +#include + +/* + * Use the lowest bit of n_klist to mark deleted nodes and exclude + * dead ones from iteration. + */ +#define KNODE_DEAD 1LU +#define KNODE_KLIST_MASK ~KNODE_DEAD + +static struct klist *knode_klist(struct klist_node *knode) +{ + return (struct klist *) + ((unsigned long)knode->n_klist & KNODE_KLIST_MASK); +} + +static bool knode_dead(struct klist_node *knode) +{ + return (unsigned long)knode->n_klist & KNODE_DEAD; +} + +static void knode_set_klist(struct klist_node *knode, struct klist *klist) +{ + knode->n_klist = klist; + /* no knode deserves to start its life dead */ + WARN_ON(knode_dead(knode)); +} + +static void knode_kill(struct klist_node *knode) +{ + /* and no knode should die twice ever either, see we're very humane */ + WARN_ON(knode_dead(knode)); + *(unsigned long *)&knode->n_klist |= KNODE_DEAD; +} + +/** + * klist_init - Initialize a klist structure. + * @k: The klist we're initializing. + * @get: The get function for the embedding object (NULL if none) + * @put: The put function for the embedding object (NULL if none) + * + * Initialises the klist structure. If the klist_node structures are + * going to be embedded in refcounted objects (necessary for safe + * deletion) then the get/put arguments are used to initialise + * functions that take and release references on the embedding + * objects. + */ +void klist_init(struct klist *k, void (*get)(struct klist_node *), + void (*put)(struct klist_node *)) +{ + INIT_LIST_HEAD(&k->k_list); + spin_lock_init(&k->k_lock); + k->get = get; + k->put = put; +} +EXPORT_SYMBOL_GPL(klist_init); + +static void add_head(struct klist *k, struct klist_node *n) +{ + spin_lock(&k->k_lock); + list_add(&n->n_node, &k->k_list); + spin_unlock(&k->k_lock); +} + +static void add_tail(struct klist *k, struct klist_node *n) +{ + spin_lock(&k->k_lock); + list_add_tail(&n->n_node, &k->k_list); + spin_unlock(&k->k_lock); +} + +static void klist_node_init(struct klist *k, struct klist_node *n) +{ + INIT_LIST_HEAD(&n->n_node); + kref_init(&n->n_ref); + knode_set_klist(n, k); + if (k->get) + k->get(n); +} + +/** + * klist_add_head - Initialize a klist_node and add it to front. + * @n: node we're adding. + * @k: klist it's going on. + */ +void klist_add_head(struct klist_node *n, struct klist *k) +{ + klist_node_init(k, n); + add_head(k, n); +} +EXPORT_SYMBOL_GPL(klist_add_head); + +/** + * klist_add_tail - Initialize a klist_node and add it to back. + * @n: node we're adding. + * @k: klist it's going on. + */ +void klist_add_tail(struct klist_node *n, struct klist *k) +{ + klist_node_init(k, n); + add_tail(k, n); +} +EXPORT_SYMBOL_GPL(klist_add_tail); + +/** + * klist_add_behind - Init a klist_node and add it after an existing node + * @n: node we're adding. + * @pos: node to put @n after + */ +void klist_add_behind(struct klist_node *n, struct klist_node *pos) +{ + struct klist *k = knode_klist(pos); + + klist_node_init(k, n); + spin_lock(&k->k_lock); + list_add(&n->n_node, &pos->n_node); + spin_unlock(&k->k_lock); +} +EXPORT_SYMBOL_GPL(klist_add_behind); + +/** + * klist_add_before - Init a klist_node and add it before an existing node + * @n: node we're adding. + * @pos: node to put @n after + */ +void klist_add_before(struct klist_node *n, struct klist_node *pos) +{ + struct klist *k = knode_klist(pos); + + klist_node_init(k, n); + spin_lock(&k->k_lock); + list_add_tail(&n->n_node, &pos->n_node); + spin_unlock(&k->k_lock); +} +EXPORT_SYMBOL_GPL(klist_add_before); + +struct klist_waiter { + struct list_head list; + struct klist_node *node; + struct task_struct *process; + int woken; +}; + +static DEFINE_SPINLOCK(klist_remove_lock); +static LIST_HEAD(klist_remove_waiters); + +static void klist_release(struct kref *kref) +{ + struct klist_waiter *waiter, *tmp; + struct klist_node *n = container_of(kref, struct klist_node, n_ref); + + WARN_ON(!knode_dead(n)); + list_del(&n->n_node); + spin_lock(&klist_remove_lock); + list_for_each_entry_safe(waiter, tmp, &klist_remove_waiters, list) { + if (waiter->node != n) + continue; + + list_del(&waiter->list); + waiter->woken = 1; + mb(); + wake_up_process(waiter->process); + } + spin_unlock(&klist_remove_lock); + knode_set_klist(n, NULL); +} + +static int klist_dec_and_del(struct klist_node *n) +{ + return kref_put(&n->n_ref, klist_release); +} + +static void klist_put(struct klist_node *n, bool kill) +{ + struct klist *k = knode_klist(n); + void (*put)(struct klist_node *) = k->put; + + spin_lock(&k->k_lock); + if (kill) + knode_kill(n); + if (!klist_dec_and_del(n)) + put = NULL; + spin_unlock(&k->k_lock); + if (put) + put(n); +} + +/** + * klist_del - Decrement the reference count of node and try to remove. + * @n: node we're deleting. + */ +void klist_del(struct klist_node *n) +{ + klist_put(n, true); +} +EXPORT_SYMBOL_GPL(klist_del); + +/** + * klist_remove - Decrement the refcount of node and wait for it to go away. + * @n: node we're removing. + */ +void klist_remove(struct klist_node *n) +{ + struct klist_waiter waiter; + + waiter.node = n; + waiter.process = current; + waiter.woken = 0; + spin_lock(&klist_remove_lock); + list_add(&waiter.list, &klist_remove_waiters); + spin_unlock(&klist_remove_lock); + + klist_del(n); + + for (;;) { + set_current_state(TASK_UNINTERRUPTIBLE); + if (waiter.woken) + break; + schedule(); + } + __set_current_state(TASK_RUNNING); +} +EXPORT_SYMBOL_GPL(klist_remove); + +/** + * klist_node_attached - Say whether a node is bound to a list or not. + * @n: Node that we're testing. + */ +int klist_node_attached(struct klist_node *n) +{ + return (n->n_klist != NULL); +} +EXPORT_SYMBOL_GPL(klist_node_attached); + +/** + * klist_iter_init_node - Initialize a klist_iter structure. + * @k: klist we're iterating. + * @i: klist_iter we're filling. + * @n: node to start with. + * + * Similar to klist_iter_init(), but starts the action off with @n, + * instead of with the list head. + */ +void klist_iter_init_node(struct klist *k, struct klist_iter *i, + struct klist_node *n) +{ + i->i_klist = k; + i->i_cur = NULL; + if (n && kref_get_unless_zero(&n->n_ref)) + i->i_cur = n; +} +EXPORT_SYMBOL_GPL(klist_iter_init_node); + +/** + * klist_iter_init - Iniitalize a klist_iter structure. + * @k: klist we're iterating. + * @i: klist_iter structure we're filling. + * + * Similar to klist_iter_init_node(), but start with the list head. + */ +void klist_iter_init(struct klist *k, struct klist_iter *i) +{ + klist_iter_init_node(k, i, NULL); +} +EXPORT_SYMBOL_GPL(klist_iter_init); + +/** + * klist_iter_exit - Finish a list iteration. + * @i: Iterator structure. + * + * Must be called when done iterating over list, as it decrements the + * refcount of the current node. Necessary in case iteration exited before + * the end of the list was reached, and always good form. + */ +void klist_iter_exit(struct klist_iter *i) +{ + if (i->i_cur) { + klist_put(i->i_cur, false); + i->i_cur = NULL; + } +} +EXPORT_SYMBOL_GPL(klist_iter_exit); + +static struct klist_node *to_klist_node(struct list_head *n) +{ + return container_of(n, struct klist_node, n_node); +} + +/** + * klist_prev - Ante up prev node in list. + * @i: Iterator structure. + * + * First grab list lock. Decrement the reference count of the previous + * node, if there was one. Grab the prev node, increment its reference + * count, drop the lock, and return that prev node. + */ +struct klist_node *klist_prev(struct klist_iter *i) +{ + void (*put)(struct klist_node *) = i->i_klist->put; + struct klist_node *last = i->i_cur; + struct klist_node *prev; + unsigned long flags; + + spin_lock_irqsave(&i->i_klist->k_lock, flags); + + if (last) { + prev = to_klist_node(last->n_node.prev); + if (!klist_dec_and_del(last)) + put = NULL; + } else + prev = to_klist_node(i->i_klist->k_list.prev); + + i->i_cur = NULL; + while (prev != to_klist_node(&i->i_klist->k_list)) { + if (likely(!knode_dead(prev))) { + kref_get(&prev->n_ref); + i->i_cur = prev; + break; + } + prev = to_klist_node(prev->n_node.prev); + } + + spin_unlock_irqrestore(&i->i_klist->k_lock, flags); + + if (put && last) + put(last); + return i->i_cur; +} +EXPORT_SYMBOL_GPL(klist_prev); + +/** + * klist_next - Ante up next node in list. + * @i: Iterator structure. + * + * First grab list lock. Decrement the reference count of the previous + * node, if there was one. Grab the next node, increment its reference + * count, drop the lock, and return that next node. + */ +struct klist_node *klist_next(struct klist_iter *i) +{ + void (*put)(struct klist_node *) = i->i_klist->put; + struct klist_node *last = i->i_cur; + struct klist_node *next; + unsigned long flags; + + spin_lock_irqsave(&i->i_klist->k_lock, flags); + + if (last) { + next = to_klist_node(last->n_node.next); + if (!klist_dec_and_del(last)) + put = NULL; + } else + next = to_klist_node(i->i_klist->k_list.next); + + i->i_cur = NULL; + while (next != to_klist_node(&i->i_klist->k_list)) { + if (likely(!knode_dead(next))) { + kref_get(&next->n_ref); + i->i_cur = next; + break; + } + next = to_klist_node(next->n_node.next); + } + + spin_unlock_irqrestore(&i->i_klist->k_lock, flags); + + if (put && last) + put(last); + return i->i_cur; +} +EXPORT_SYMBOL_GPL(klist_next); -- cgit v1.2.3