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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
+.. _VAS-API:
+
+===================================================
+Virtual Accelerator Switchboard (VAS) userspace API
+===================================================
+
+Introduction
+============
+
+Power9 processor introduced Virtual Accelerator Switchboard (VAS) which
+allows both userspace and kernel communicate to co-processor
+(hardware accelerator) referred to as the Nest Accelerator (NX). The NX
+unit comprises of one or more hardware engines or co-processor types
+such as 842 compression, GZIP compression and encryption. On power9,
+userspace applications will have access to only GZIP Compression engine
+which supports ZLIB and GZIP compression algorithms in the hardware.
+
+To communicate with NX, kernel has to establish a channel or window and
+then requests can be submitted directly without kernel involvement.
+Requests to the GZIP engine must be formatted as a co-processor Request
+Block (CRB) and these CRBs must be submitted to the NX using COPY/PASTE
+instructions to paste the CRB to hardware address that is associated with
+the engine's request queue.
+
+The GZIP engine provides two priority levels of requests: Normal and
+High. Only Normal requests are supported from userspace right now.
+
+This document explains userspace API that is used to interact with
+kernel to setup channel / window which can be used to send compression
+requests directly to NX accelerator.
+
+
+Overview
+========
+
+Application access to the GZIP engine is provided through
+/dev/crypto/nx-gzip device node implemented by the VAS/NX device driver.
+An application must open the /dev/crypto/nx-gzip device to obtain a file
+descriptor (fd). Then should issue VAS_TX_WIN_OPEN ioctl with this fd to
+establish connection to the engine. It means send window is opened on GZIP
+engine for this process. Once a connection is established, the application
+should use the mmap() system call to map the hardware address of engine's
+request queue into the application's virtual address space.
+
+The application can then submit one or more requests to the engine by
+using copy/paste instructions and pasting the CRBs to the virtual address
+(aka paste_address) returned by mmap(). User space can close the
+established connection or send window by closing the file descriptior
+(close(fd)) or upon the process exit.
+
+Note that applications can send several requests with the same window or
+can establish multiple windows, but one window for each file descriptor.
+
+Following sections provide additional details and references about the
+individual steps.
+
+NX-GZIP Device Node
+===================
+
+There is one /dev/crypto/nx-gzip node in the system and it provides
+access to all GZIP engines in the system. The only valid operations on
+/dev/crypto/nx-gzip are:
+
+ * open() the device for read and write.
+ * issue VAS_TX_WIN_OPEN ioctl
+ * mmap() the engine's request queue into application's virtual
+ address space (i.e. get a paste_address for the co-processor
+ engine).
+ * close the device node.
+
+Other file operations on this device node are undefined.
+
+Note that the copy and paste operations go directly to the hardware and
+do not go through this device. Refer COPY/PASTE document for more
+details.
+
+Although a system may have several instances of the NX co-processor
+engines (typically, one per P9 chip) there is just one
+/dev/crypto/nx-gzip device node in the system. When the nx-gzip device
+node is opened, Kernel opens send window on a suitable instance of NX
+accelerator. It finds CPU on which the user process is executing and
+determine the NX instance for the corresponding chip on which this CPU
+belongs.
+
+Applications may chose a specific instance of the NX co-processor using
+the vas_id field in the VAS_TX_WIN_OPEN ioctl as detailed below.
+
+A userspace library libnxz is available here but still in development:
+
+ https://github.com/abalib/power-gzip
+
+Applications that use inflate / deflate calls can link with libnxz
+instead of libz and use NX GZIP compression without any modification.
+
+Open /dev/crypto/nx-gzip
+========================
+
+The nx-gzip device should be opened for read and write. No special
+privileges are needed to open the device. Each window corresponds to one
+file descriptor. So if the userspace process needs multiple windows,
+several open calls have to be issued.
+
+See open(2) system call man pages for other details such as return values,
+error codes and restrictions.
+
+VAS_TX_WIN_OPEN ioctl
+=====================
+
+Applications should use the VAS_TX_WIN_OPEN ioctl as follows to establish
+a connection with NX co-processor engine:
+
+ ::
+
+ struct vas_tx_win_open_attr {
+ __u32 version;
+ __s16 vas_id; /* specific instance of vas or -1
+ for default */
+ __u16 reserved1;
+ __u64 flags; /* For future use */
+ __u64 reserved2[6];
+ };
+
+ version:
+ The version field must be currently set to 1.
+ vas_id:
+ If '-1' is passed, kernel will make a best-effort attempt
+ to assign an optimal instance of NX for the process. To
+ select the specific VAS instance, refer
+ "Discovery of available VAS engines" section below.
+
+ flags, reserved1 and reserved2[6] fields are for future extension
+ and must be set to 0.
+
+ The attributes attr for the VAS_TX_WIN_OPEN ioctl are defined as
+ follows::
+
+ #define VAS_MAGIC 'v'
+ #define VAS_TX_WIN_OPEN _IOW(VAS_MAGIC, 1,
+ struct vas_tx_win_open_attr)
+
+ struct vas_tx_win_open_attr attr;
+ rc = ioctl(fd, VAS_TX_WIN_OPEN, &attr);
+
+ The VAS_TX_WIN_OPEN ioctl returns 0 on success. On errors, it
+ returns -1 and sets the errno variable to indicate the error.
+
+ Error conditions:
+
+ ====== ================================================
+ EINVAL fd does not refer to a valid VAS device.
+ EINVAL Invalid vas ID
+ EINVAL version is not set with proper value
+ EEXIST Window is already opened for the given fd
+ ENOMEM Memory is not available to allocate window
+ ENOSPC System has too many active windows (connections)
+ opened
+ EINVAL reserved fields are not set to 0.
+ ====== ================================================
+
+ See the ioctl(2) man page for more details, error codes and
+ restrictions.
+
+mmap() NX-GZIP device
+=====================
+
+The mmap() system call for a NX-GZIP device fd returns a paste_address
+that the application can use to copy/paste its CRB to the hardware engines.
+
+ ::
+
+ paste_addr = mmap(addr, size, prot, flags, fd, offset);
+
+ Only restrictions on mmap for a NX-GZIP device fd are:
+
+ * size should be PAGE_SIZE
+ * offset parameter should be 0ULL
+
+ Refer to mmap(2) man page for additional details/restrictions.
+ In addition to the error conditions listed on the mmap(2) man
+ page, can also fail with one of the following error codes:
+
+ ====== =============================================
+ EINVAL fd is not associated with an open window
+ (i.e mmap() does not follow a successful call
+ to the VAS_TX_WIN_OPEN ioctl).
+ EINVAL offset field is not 0ULL.
+ ====== =============================================
+
+Discovery of available VAS engines
+==================================
+
+Each available VAS instance in the system will have a device tree node
+like /proc/device-tree/vas@* or /proc/device-tree/xscom@*/vas@*.
+Determine the chip or VAS instance and use the corresponding ibm,vas-id
+property value in this node to select specific VAS instance.
+
+Copy/Paste operations
+=====================
+
+Applications should use the copy and paste instructions to send CRB to NX.
+Refer section 4.4 in PowerISA for Copy/Paste instructions:
+https://openpowerfoundation.org/?resource_lib=power-isa-version-3-0
+
+CRB Specification and use NX
+============================
+
+Applications should format requests to the co-processor using the
+co-processor Request Block (CRBs). Refer NX-GZIP user's manual for the format
+of CRB and use NX from userspace such as sending requests and checking
+request status.
+
+NX Fault handling
+=================
+
+Applications send requests to NX and wait for the status by polling on
+co-processor Status Block (CSB) flags. NX updates status in CSB after each
+request is processed. Refer NX-GZIP user's manual for the format of CSB and
+status flags.
+
+In case if NX encounters translation error (called NX page fault) on CSB
+address or any request buffer, raises an interrupt on the CPU to handle the
+fault. Page fault can happen if an application passes invalid addresses or
+request buffers are not in memory. The operating system handles the fault by
+updating CSB with the following data::
+
+ csb.flags = CSB_V;
+ csb.cc = CSB_CC_FAULT_ADDRESS;
+ csb.ce = CSB_CE_TERMINATION;
+ csb.address = fault_address;
+
+When an application receives translation error, it can touch or access
+the page that has a fault address so that this page will be in memory. Then
+the application can resend this request to NX.
+
+If the OS can not update CSB due to invalid CSB address, sends SEGV signal
+to the process who opened the send window on which the original request was
+issued. This signal returns with the following siginfo struct::
+
+ siginfo.si_signo = SIGSEGV;
+ siginfo.si_errno = EFAULT;
+ siginfo.si_code = SEGV_MAPERR;
+ siginfo.si_addr = CSB adress;
+
+In the case of multi-thread applications, NX send windows can be shared
+across all threads. For example, a child thread can open a send window,
+but other threads can send requests to NX using this window. These
+requests will be successful even in the case of OS handling faults as long
+as CSB address is valid. If the NX request contains an invalid CSB address,
+the signal will be sent to the child thread that opened the window. But if
+the thread is exited without closing the window and the request is issued
+using this window. the signal will be issued to the thread group leader
+(tgid). It is up to the application whether to ignore or handle these
+signals.
+
+NX-GZIP User's Manual:
+https://github.com/libnxz/power-gzip/blob/master/doc/power_nx_gzip_um.pdf
+
+Simple example
+==============
+
+ ::
+
+ int use_nx_gzip()
+ {
+ int rc, fd;
+ void *addr;
+ struct vas_setup_attr txattr;
+
+ fd = open("/dev/crypto/nx-gzip", O_RDWR);
+ if (fd < 0) {
+ fprintf(stderr, "open nx-gzip failed\n");
+ return -1;
+ }
+ memset(&txattr, 0, sizeof(txattr));
+ txattr.version = 1;
+ txattr.vas_id = -1
+ rc = ioctl(fd, VAS_TX_WIN_OPEN,
+ (unsigned long)&txattr);
+ if (rc < 0) {
+ fprintf(stderr, "ioctl() n %d, error %d\n",
+ rc, errno);
+ return rc;
+ }
+ addr = mmap(NULL, 4096, PROT_READ|PROT_WRITE,
+ MAP_SHARED, fd, 0ULL);
+ if (addr == MAP_FAILED) {
+ fprintf(stderr, "mmap() failed, errno %d\n",
+ errno);
+ return -errno;
+ }
+ do {
+ //Format CRB request with compression or
+ //uncompression
+ // Refer tests for vas_copy/vas_paste
+ vas_copy((&crb, 0, 1);
+ vas_paste(addr, 0, 1);
+ // Poll on csb.flags with timeout
+ // csb address is listed in CRB
+ } while (true)
+ close(fd) or window can be closed upon process exit
+ }
+
+ Refer https://github.com/libnxz/power-gzip for tests or more
+ use cases.