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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
commit5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch)
treecc5c2d0a898769fd59549594fedb3ee6f84e59a0 /arch/mips/mm/context.c
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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(). ...
Diffstat (limited to 'arch/mips/mm/context.c')
-rw-r--r--arch/mips/mm/context.c290
1 files changed, 290 insertions, 0 deletions
diff --git a/arch/mips/mm/context.c b/arch/mips/mm/context.c
new file mode 100644
index 000000000..966f40066
--- /dev/null
+++ b/arch/mips/mm/context.c
@@ -0,0 +1,290 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/atomic.h>
+#include <linux/mmu_context.h>
+#include <linux/percpu.h>
+#include <linux/spinlock.h>
+
+static DEFINE_RAW_SPINLOCK(cpu_mmid_lock);
+
+static atomic64_t mmid_version;
+static unsigned int num_mmids;
+static unsigned long *mmid_map;
+
+static DEFINE_PER_CPU(u64, reserved_mmids);
+static cpumask_t tlb_flush_pending;
+
+static bool asid_versions_eq(int cpu, u64 a, u64 b)
+{
+ return ((a ^ b) & asid_version_mask(cpu)) == 0;
+}
+
+void get_new_mmu_context(struct mm_struct *mm)
+{
+ unsigned int cpu;
+ u64 asid;
+
+ /*
+ * This function is specific to ASIDs, and should not be called when
+ * MMIDs are in use.
+ */
+ if (WARN_ON(IS_ENABLED(CONFIG_DEBUG_VM) && cpu_has_mmid))
+ return;
+
+ cpu = smp_processor_id();
+ asid = asid_cache(cpu);
+
+ if (!((asid += cpu_asid_inc()) & cpu_asid_mask(&cpu_data[cpu]))) {
+ if (cpu_has_vtag_icache)
+ flush_icache_all();
+ local_flush_tlb_all(); /* start new asid cycle */
+ }
+
+ set_cpu_context(cpu, mm, asid);
+ asid_cache(cpu) = asid;
+}
+EXPORT_SYMBOL_GPL(get_new_mmu_context);
+
+void check_mmu_context(struct mm_struct *mm)
+{
+ unsigned int cpu = smp_processor_id();
+
+ /*
+ * This function is specific to ASIDs, and should not be called when
+ * MMIDs are in use.
+ */
+ if (WARN_ON(IS_ENABLED(CONFIG_DEBUG_VM) && cpu_has_mmid))
+ return;
+
+ /* Check if our ASID is of an older version and thus invalid */
+ if (!asid_versions_eq(cpu, cpu_context(cpu, mm), asid_cache(cpu)))
+ get_new_mmu_context(mm);
+}
+EXPORT_SYMBOL_GPL(check_mmu_context);
+
+static void flush_context(void)
+{
+ u64 mmid;
+ int cpu;
+
+ /* Update the list of reserved MMIDs and the MMID bitmap */
+ bitmap_zero(mmid_map, num_mmids);
+
+ /* Reserve an MMID for kmap/wired entries */
+ __set_bit(MMID_KERNEL_WIRED, mmid_map);
+
+ for_each_possible_cpu(cpu) {
+ mmid = xchg_relaxed(&cpu_data[cpu].asid_cache, 0);
+
+ /*
+ * If this CPU has already been through a
+ * rollover, but hasn't run another task in
+ * the meantime, we must preserve its reserved
+ * MMID, as this is the only trace we have of
+ * the process it is still running.
+ */
+ if (mmid == 0)
+ mmid = per_cpu(reserved_mmids, cpu);
+
+ __set_bit(mmid & cpu_asid_mask(&cpu_data[cpu]), mmid_map);
+ per_cpu(reserved_mmids, cpu) = mmid;
+ }
+
+ /*
+ * Queue a TLB invalidation for each CPU to perform on next
+ * context-switch
+ */
+ cpumask_setall(&tlb_flush_pending);
+}
+
+static bool check_update_reserved_mmid(u64 mmid, u64 newmmid)
+{
+ bool hit;
+ int cpu;
+
+ /*
+ * Iterate over the set of reserved MMIDs looking for a match.
+ * If we find one, then we can update our mm to use newmmid
+ * (i.e. the same MMID in the current generation) but we can't
+ * exit the loop early, since we need to ensure that all copies
+ * of the old MMID are updated to reflect the mm. Failure to do
+ * so could result in us missing the reserved MMID in a future
+ * generation.
+ */
+ hit = false;
+ for_each_possible_cpu(cpu) {
+ if (per_cpu(reserved_mmids, cpu) == mmid) {
+ hit = true;
+ per_cpu(reserved_mmids, cpu) = newmmid;
+ }
+ }
+
+ return hit;
+}
+
+static u64 get_new_mmid(struct mm_struct *mm)
+{
+ static u32 cur_idx = MMID_KERNEL_WIRED + 1;
+ u64 mmid, version, mmid_mask;
+
+ mmid = cpu_context(0, mm);
+ version = atomic64_read(&mmid_version);
+ mmid_mask = cpu_asid_mask(&boot_cpu_data);
+
+ if (!asid_versions_eq(0, mmid, 0)) {
+ u64 newmmid = version | (mmid & mmid_mask);
+
+ /*
+ * If our current MMID was active during a rollover, we
+ * can continue to use it and this was just a false alarm.
+ */
+ if (check_update_reserved_mmid(mmid, newmmid)) {
+ mmid = newmmid;
+ goto set_context;
+ }
+
+ /*
+ * We had a valid MMID in a previous life, so try to re-use
+ * it if possible.
+ */
+ if (!__test_and_set_bit(mmid & mmid_mask, mmid_map)) {
+ mmid = newmmid;
+ goto set_context;
+ }
+ }
+
+ /* Allocate a free MMID */
+ mmid = find_next_zero_bit(mmid_map, num_mmids, cur_idx);
+ if (mmid != num_mmids)
+ goto reserve_mmid;
+
+ /* We're out of MMIDs, so increment the global version */
+ version = atomic64_add_return_relaxed(asid_first_version(0),
+ &mmid_version);
+
+ /* Note currently active MMIDs & mark TLBs as requiring flushes */
+ flush_context();
+
+ /* We have more MMIDs than CPUs, so this will always succeed */
+ mmid = find_first_zero_bit(mmid_map, num_mmids);
+
+reserve_mmid:
+ __set_bit(mmid, mmid_map);
+ cur_idx = mmid;
+ mmid |= version;
+set_context:
+ set_cpu_context(0, mm, mmid);
+ return mmid;
+}
+
+void check_switch_mmu_context(struct mm_struct *mm)
+{
+ unsigned int cpu = smp_processor_id();
+ u64 ctx, old_active_mmid;
+ unsigned long flags;
+
+ if (!cpu_has_mmid) {
+ check_mmu_context(mm);
+ write_c0_entryhi(cpu_asid(cpu, mm));
+ goto setup_pgd;
+ }
+
+ /*
+ * MMID switch fast-path, to avoid acquiring cpu_mmid_lock when it's
+ * unnecessary.
+ *
+ * The memory ordering here is subtle. If our active_mmids is non-zero
+ * and the MMID matches the current version, then we update the CPU's
+ * asid_cache with a relaxed cmpxchg. Racing with a concurrent rollover
+ * means that either:
+ *
+ * - We get a zero back from the cmpxchg and end up waiting on
+ * cpu_mmid_lock in check_mmu_context(). Taking the lock synchronises
+ * with the rollover and so we are forced to see the updated
+ * generation.
+ *
+ * - We get a valid MMID back from the cmpxchg, which means the
+ * relaxed xchg in flush_context will treat us as reserved
+ * because atomic RmWs are totally ordered for a given location.
+ */
+ ctx = cpu_context(cpu, mm);
+ old_active_mmid = READ_ONCE(cpu_data[cpu].asid_cache);
+ if (!old_active_mmid ||
+ !asid_versions_eq(cpu, ctx, atomic64_read(&mmid_version)) ||
+ !cmpxchg_relaxed(&cpu_data[cpu].asid_cache, old_active_mmid, ctx)) {
+ raw_spin_lock_irqsave(&cpu_mmid_lock, flags);
+
+ ctx = cpu_context(cpu, mm);
+ if (!asid_versions_eq(cpu, ctx, atomic64_read(&mmid_version)))
+ ctx = get_new_mmid(mm);
+
+ WRITE_ONCE(cpu_data[cpu].asid_cache, ctx);
+ raw_spin_unlock_irqrestore(&cpu_mmid_lock, flags);
+ }
+
+ /*
+ * Invalidate the local TLB if needed. Note that we must only clear our
+ * bit in tlb_flush_pending after this is complete, so that the
+ * cpu_has_shared_ftlb_entries case below isn't misled.
+ */
+ if (cpumask_test_cpu(cpu, &tlb_flush_pending)) {
+ if (cpu_has_vtag_icache)
+ flush_icache_all();
+ local_flush_tlb_all();
+ cpumask_clear_cpu(cpu, &tlb_flush_pending);
+ }
+
+ write_c0_memorymapid(ctx & cpu_asid_mask(&boot_cpu_data));
+
+ /*
+ * If this CPU shares FTLB entries with its siblings and one or more of
+ * those siblings hasn't yet invalidated its TLB following a version
+ * increase then we need to invalidate any TLB entries for our MMID
+ * that we might otherwise pick up from a sibling.
+ *
+ * We ifdef on CONFIG_SMP because cpu_sibling_map isn't defined in
+ * CONFIG_SMP=n kernels.
+ */
+#ifdef CONFIG_SMP
+ if (cpu_has_shared_ftlb_entries &&
+ cpumask_intersects(&tlb_flush_pending, &cpu_sibling_map[cpu])) {
+ /* Ensure we operate on the new MMID */
+ mtc0_tlbw_hazard();
+
+ /*
+ * Invalidate all TLB entries associated with the new
+ * MMID, and wait for the invalidation to complete.
+ */
+ ginvt_mmid();
+ sync_ginv();
+ }
+#endif
+
+setup_pgd:
+ TLBMISS_HANDLER_SETUP_PGD(mm->pgd);
+}
+EXPORT_SYMBOL_GPL(check_switch_mmu_context);
+
+static int mmid_init(void)
+{
+ if (!cpu_has_mmid)
+ return 0;
+
+ /*
+ * Expect allocation after rollover to fail if we don't have at least
+ * one more MMID than CPUs.
+ */
+ num_mmids = asid_first_version(0);
+ WARN_ON(num_mmids <= num_possible_cpus());
+
+ atomic64_set(&mmid_version, asid_first_version(0));
+ mmid_map = bitmap_zalloc(num_mmids, GFP_KERNEL);
+ if (!mmid_map)
+ panic("Failed to allocate bitmap for %u MMIDs\n", num_mmids);
+
+ /* Reserve an MMID for kmap/wired entries */
+ __set_bit(MMID_KERNEL_WIRED, mmid_map);
+
+ pr_info("MMID allocator initialised with %u entries\n", num_mmids);
+ return 0;
+}
+early_initcall(mmid_init);