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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/riscv/lib/memmove.S
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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/riscv/lib/memmove.S')
-rw-r--r--arch/riscv/lib/memmove.S316
1 files changed, 316 insertions, 0 deletions
diff --git a/arch/riscv/lib/memmove.S b/arch/riscv/lib/memmove.S
new file mode 100644
index 000000000..e0609e1f0
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+++ b/arch/riscv/lib/memmove.S
@@ -0,0 +1,316 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2022 Michael T. Kloos <michael@michaelkloos.com>
+ */
+
+#include <linux/linkage.h>
+#include <asm/asm.h>
+
+SYM_FUNC_START(__memmove)
+SYM_FUNC_START_WEAK(memmove)
+ /*
+ * Returns
+ * a0 - dest
+ *
+ * Parameters
+ * a0 - Inclusive first byte of dest
+ * a1 - Inclusive first byte of src
+ * a2 - Length of copy n
+ *
+ * Because the return matches the parameter register a0,
+ * we will not clobber or modify that register.
+ *
+ * Note: This currently only works on little-endian.
+ * To port to big-endian, reverse the direction of shifts
+ * in the 2 misaligned fixup copy loops.
+ */
+
+ /* Return if nothing to do */
+ beq a0, a1, return_from_memmove
+ beqz a2, return_from_memmove
+
+ /*
+ * Register Uses
+ * Forward Copy: a1 - Index counter of src
+ * Reverse Copy: a4 - Index counter of src
+ * Forward Copy: t3 - Index counter of dest
+ * Reverse Copy: t4 - Index counter of dest
+ * Both Copy Modes: t5 - Inclusive first multibyte/aligned of dest
+ * Both Copy Modes: t6 - Non-Inclusive last multibyte/aligned of dest
+ * Both Copy Modes: t0 - Link / Temporary for load-store
+ * Both Copy Modes: t1 - Temporary for load-store
+ * Both Copy Modes: t2 - Temporary for load-store
+ * Both Copy Modes: a5 - dest to src alignment offset
+ * Both Copy Modes: a6 - Shift ammount
+ * Both Copy Modes: a7 - Inverse Shift ammount
+ * Both Copy Modes: a2 - Alternate breakpoint for unrolled loops
+ */
+
+ /*
+ * Solve for some register values now.
+ * Byte copy does not need t5 or t6.
+ */
+ mv t3, a0
+ add t4, a0, a2
+ add a4, a1, a2
+
+ /*
+ * Byte copy if copying less than (2 * SZREG) bytes. This can
+ * cause problems with the bulk copy implementation and is
+ * small enough not to bother.
+ */
+ andi t0, a2, -(2 * SZREG)
+ beqz t0, byte_copy
+
+ /*
+ * Now solve for t5 and t6.
+ */
+ andi t5, t3, -SZREG
+ andi t6, t4, -SZREG
+ /*
+ * If dest(Register t3) rounded down to the nearest naturally
+ * aligned SZREG address, does not equal dest, then add SZREG
+ * to find the low-bound of SZREG alignment in the dest memory
+ * region. Note that this could overshoot the dest memory
+ * region if n is less than SZREG. This is one reason why
+ * we always byte copy if n is less than SZREG.
+ * Otherwise, dest is already naturally aligned to SZREG.
+ */
+ beq t5, t3, 1f
+ addi t5, t5, SZREG
+ 1:
+
+ /*
+ * If the dest and src are co-aligned to SZREG, then there is
+ * no need for the full rigmarole of a full misaligned fixup copy.
+ * Instead, do a simpler co-aligned copy.
+ */
+ xor t0, a0, a1
+ andi t1, t0, (SZREG - 1)
+ beqz t1, coaligned_copy
+ /* Fall through to misaligned fixup copy */
+
+misaligned_fixup_copy:
+ bltu a1, a0, misaligned_fixup_copy_reverse
+
+misaligned_fixup_copy_forward:
+ jal t0, byte_copy_until_aligned_forward
+
+ andi a5, a1, (SZREG - 1) /* Find the alignment offset of src (a1) */
+ slli a6, a5, 3 /* Multiply by 8 to convert that to bits to shift */
+ sub a5, a1, t3 /* Find the difference between src and dest */
+ andi a1, a1, -SZREG /* Align the src pointer */
+ addi a2, t6, SZREG /* The other breakpoint for the unrolled loop*/
+
+ /*
+ * Compute The Inverse Shift
+ * a7 = XLEN - a6 = XLEN + -a6
+ * 2s complement negation to find the negative: -a6 = ~a6 + 1
+ * Add that to XLEN. XLEN = SZREG * 8.
+ */
+ not a7, a6
+ addi a7, a7, (SZREG * 8 + 1)
+
+ /*
+ * Fix Misalignment Copy Loop - Forward
+ * load_val0 = load_ptr[0];
+ * do {
+ * load_val1 = load_ptr[1];
+ * store_ptr += 2;
+ * store_ptr[0 - 2] = (load_val0 >> {a6}) | (load_val1 << {a7});
+ *
+ * if (store_ptr == {a2})
+ * break;
+ *
+ * load_val0 = load_ptr[2];
+ * load_ptr += 2;
+ * store_ptr[1 - 2] = (load_val1 >> {a6}) | (load_val0 << {a7});
+ *
+ * } while (store_ptr != store_ptr_end);
+ * store_ptr = store_ptr_end;
+ */
+
+ REG_L t0, (0 * SZREG)(a1)
+ 1:
+ REG_L t1, (1 * SZREG)(a1)
+ addi t3, t3, (2 * SZREG)
+ srl t0, t0, a6
+ sll t2, t1, a7
+ or t2, t0, t2
+ REG_S t2, ((0 * SZREG) - (2 * SZREG))(t3)
+
+ beq t3, a2, 2f
+
+ REG_L t0, (2 * SZREG)(a1)
+ addi a1, a1, (2 * SZREG)
+ srl t1, t1, a6
+ sll t2, t0, a7
+ or t2, t1, t2
+ REG_S t2, ((1 * SZREG) - (2 * SZREG))(t3)
+
+ bne t3, t6, 1b
+ 2:
+ mv t3, t6 /* Fix the dest pointer in case the loop was broken */
+
+ add a1, t3, a5 /* Restore the src pointer */
+ j byte_copy_forward /* Copy any remaining bytes */
+
+misaligned_fixup_copy_reverse:
+ jal t0, byte_copy_until_aligned_reverse
+
+ andi a5, a4, (SZREG - 1) /* Find the alignment offset of src (a4) */
+ slli a6, a5, 3 /* Multiply by 8 to convert that to bits to shift */
+ sub a5, a4, t4 /* Find the difference between src and dest */
+ andi a4, a4, -SZREG /* Align the src pointer */
+ addi a2, t5, -SZREG /* The other breakpoint for the unrolled loop*/
+
+ /*
+ * Compute The Inverse Shift
+ * a7 = XLEN - a6 = XLEN + -a6
+ * 2s complement negation to find the negative: -a6 = ~a6 + 1
+ * Add that to XLEN. XLEN = SZREG * 8.
+ */
+ not a7, a6
+ addi a7, a7, (SZREG * 8 + 1)
+
+ /*
+ * Fix Misalignment Copy Loop - Reverse
+ * load_val1 = load_ptr[0];
+ * do {
+ * load_val0 = load_ptr[-1];
+ * store_ptr -= 2;
+ * store_ptr[1] = (load_val0 >> {a6}) | (load_val1 << {a7});
+ *
+ * if (store_ptr == {a2})
+ * break;
+ *
+ * load_val1 = load_ptr[-2];
+ * load_ptr -= 2;
+ * store_ptr[0] = (load_val1 >> {a6}) | (load_val0 << {a7});
+ *
+ * } while (store_ptr != store_ptr_end);
+ * store_ptr = store_ptr_end;
+ */
+
+ REG_L t1, ( 0 * SZREG)(a4)
+ 1:
+ REG_L t0, (-1 * SZREG)(a4)
+ addi t4, t4, (-2 * SZREG)
+ sll t1, t1, a7
+ srl t2, t0, a6
+ or t2, t1, t2
+ REG_S t2, ( 1 * SZREG)(t4)
+
+ beq t4, a2, 2f
+
+ REG_L t1, (-2 * SZREG)(a4)
+ addi a4, a4, (-2 * SZREG)
+ sll t0, t0, a7
+ srl t2, t1, a6
+ or t2, t0, t2
+ REG_S t2, ( 0 * SZREG)(t4)
+
+ bne t4, t5, 1b
+ 2:
+ mv t4, t5 /* Fix the dest pointer in case the loop was broken */
+
+ add a4, t4, a5 /* Restore the src pointer */
+ j byte_copy_reverse /* Copy any remaining bytes */
+
+/*
+ * Simple copy loops for SZREG co-aligned memory locations.
+ * These also make calls to do byte copies for any unaligned
+ * data at their terminations.
+ */
+coaligned_copy:
+ bltu a1, a0, coaligned_copy_reverse
+
+coaligned_copy_forward:
+ jal t0, byte_copy_until_aligned_forward
+
+ 1:
+ REG_L t1, ( 0 * SZREG)(a1)
+ addi a1, a1, SZREG
+ addi t3, t3, SZREG
+ REG_S t1, (-1 * SZREG)(t3)
+ bne t3, t6, 1b
+
+ j byte_copy_forward /* Copy any remaining bytes */
+
+coaligned_copy_reverse:
+ jal t0, byte_copy_until_aligned_reverse
+
+ 1:
+ REG_L t1, (-1 * SZREG)(a4)
+ addi a4, a4, -SZREG
+ addi t4, t4, -SZREG
+ REG_S t1, ( 0 * SZREG)(t4)
+ bne t4, t5, 1b
+
+ j byte_copy_reverse /* Copy any remaining bytes */
+
+/*
+ * These are basically sub-functions within the function. They
+ * are used to byte copy until the dest pointer is in alignment.
+ * At which point, a bulk copy method can be used by the
+ * calling code. These work on the same registers as the bulk
+ * copy loops. Therefore, the register values can be picked
+ * up from where they were left and we avoid code duplication
+ * without any overhead except the call in and return jumps.
+ */
+byte_copy_until_aligned_forward:
+ beq t3, t5, 2f
+ 1:
+ lb t1, 0(a1)
+ addi a1, a1, 1
+ addi t3, t3, 1
+ sb t1, -1(t3)
+ bne t3, t5, 1b
+ 2:
+ jalr zero, 0x0(t0) /* Return to multibyte copy loop */
+
+byte_copy_until_aligned_reverse:
+ beq t4, t6, 2f
+ 1:
+ lb t1, -1(a4)
+ addi a4, a4, -1
+ addi t4, t4, -1
+ sb t1, 0(t4)
+ bne t4, t6, 1b
+ 2:
+ jalr zero, 0x0(t0) /* Return to multibyte copy loop */
+
+/*
+ * Simple byte copy loops.
+ * These will byte copy until they reach the end of data to copy.
+ * At that point, they will call to return from memmove.
+ */
+byte_copy:
+ bltu a1, a0, byte_copy_reverse
+
+byte_copy_forward:
+ beq t3, t4, 2f
+ 1:
+ lb t1, 0(a1)
+ addi a1, a1, 1
+ addi t3, t3, 1
+ sb t1, -1(t3)
+ bne t3, t4, 1b
+ 2:
+ ret
+
+byte_copy_reverse:
+ beq t4, t3, 2f
+ 1:
+ lb t1, -1(a4)
+ addi a4, a4, -1
+ addi t4, t4, -1
+ sb t1, 0(t4)
+ bne t4, t3, 1b
+ 2:
+
+return_from_memmove:
+ ret
+
+SYM_FUNC_END(memmove)
+SYM_FUNC_END(__memmove)