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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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+=====================
+SCSI Interfaces Guide
+=====================
+
+:Author: James Bottomley
+:Author: Rob Landley
+
+Introduction
+============
+
+Protocol vs bus
+---------------
+
+Once upon a time, the Small Computer Systems Interface defined both a
+parallel I/O bus and a data protocol to connect a wide variety of
+peripherals (disk drives, tape drives, modems, printers, scanners,
+optical drives, test equipment, and medical devices) to a host computer.
+
+Although the old parallel (fast/wide/ultra) SCSI bus has largely fallen
+out of use, the SCSI command set is more widely used than ever to
+communicate with devices over a number of different busses.
+
+The `SCSI protocol <http://www.t10.org/scsi-3.htm>`__ is a big-endian
+peer-to-peer packet based protocol. SCSI commands are 6, 10, 12, or 16
+bytes long, often followed by an associated data payload.
+
+SCSI commands can be transported over just about any kind of bus, and
+are the default protocol for storage devices attached to USB, SATA, SAS,
+Fibre Channel, FireWire, and ATAPI devices. SCSI packets are also
+commonly exchanged over Infiniband,
+`I2O <http://i2o.shadowconnect.com/faq.php>`__, TCP/IP
+(`iSCSI <https://en.wikipedia.org/wiki/ISCSI>`__), even `Parallel
+ports <http://cyberelk.net/tim/parport/parscsi.html>`__.
+
+Design of the Linux SCSI subsystem
+----------------------------------
+
+The SCSI subsystem uses a three layer design, with upper, mid, and low
+layers. Every operation involving the SCSI subsystem (such as reading a
+sector from a disk) uses one driver at each of the 3 levels: one upper
+layer driver, one lower layer driver, and the SCSI midlayer.
+
+The SCSI upper layer provides the interface between userspace and the
+kernel, in the form of block and char device nodes for I/O and ioctl().
+The SCSI lower layer contains drivers for specific hardware devices.
+
+In between is the SCSI mid-layer, analogous to a network routing layer
+such as the IPv4 stack. The SCSI mid-layer routes a packet based data
+protocol between the upper layer's /dev nodes and the corresponding
+devices in the lower layer. It manages command queues, provides error
+handling and power management functions, and responds to ioctl()
+requests.
+
+SCSI upper layer
+================
+
+The upper layer supports the user-kernel interface by providing device
+nodes.
+
+sd (SCSI Disk)
+--------------
+
+sd (sd_mod.o)
+
+sr (SCSI CD-ROM)
+----------------
+
+sr (sr_mod.o)
+
+st (SCSI Tape)
+--------------
+
+st (st.o)
+
+sg (SCSI Generic)
+-----------------
+
+sg (sg.o)
+
+ch (SCSI Media Changer)
+-----------------------
+
+ch (ch.c)
+
+SCSI mid layer
+==============
+
+SCSI midlayer implementation
+----------------------------
+
+include/scsi/scsi_device.h
+~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. kernel-doc:: include/scsi/scsi_device.h
+ :internal:
+
+drivers/scsi/scsi.c
+~~~~~~~~~~~~~~~~~~~
+
+Main file for the SCSI midlayer.
+
+.. kernel-doc:: drivers/scsi/scsi.c
+ :export:
+
+drivers/scsi/scsicam.c
+~~~~~~~~~~~~~~~~~~~~~~
+
+`SCSI Common Access
+Method <http://www.t10.org/ftp/t10/drafts/cam/cam-r12b.pdf>`__ support
+functions, for use with HDIO_GETGEO, etc.
+
+.. kernel-doc:: drivers/scsi/scsicam.c
+ :export:
+
+drivers/scsi/scsi_error.c
+~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Common SCSI error/timeout handling routines.
+
+.. kernel-doc:: drivers/scsi/scsi_error.c
+ :export:
+
+drivers/scsi/scsi_devinfo.c
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Manage scsi_dev_info_list, which tracks blacklisted and whitelisted
+devices.
+
+.. kernel-doc:: drivers/scsi/scsi_devinfo.c
+ :internal:
+
+drivers/scsi/scsi_ioctl.c
+~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Handle ioctl() calls for SCSI devices.
+
+.. kernel-doc:: drivers/scsi/scsi_ioctl.c
+ :export:
+
+drivers/scsi/scsi_lib.c
+~~~~~~~~~~~~~~~~~~~~~~~~
+
+SCSI queuing library.
+
+.. kernel-doc:: drivers/scsi/scsi_lib.c
+ :export:
+
+drivers/scsi/scsi_lib_dma.c
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+SCSI library functions depending on DMA (map and unmap scatter-gather
+lists).
+
+.. kernel-doc:: drivers/scsi/scsi_lib_dma.c
+ :export:
+
+drivers/scsi/scsi_proc.c
+~~~~~~~~~~~~~~~~~~~~~~~~~
+
+The functions in this file provide an interface between the PROC file
+system and the SCSI device drivers It is mainly used for debugging,
+statistics and to pass information directly to the lowlevel driver. I.E.
+plumbing to manage /proc/scsi/\*
+
+.. kernel-doc:: drivers/scsi/scsi_proc.c
+ :internal:
+
+drivers/scsi/scsi_netlink.c
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Infrastructure to provide async events from transports to userspace via
+netlink, using a single NETLINK_SCSITRANSPORT protocol for all
+transports. See `the original patch
+submission <http://marc.info/?l=linux-scsi&m=115507374832500&w=2>`__ for
+more details.
+
+.. kernel-doc:: drivers/scsi/scsi_netlink.c
+ :internal:
+
+drivers/scsi/scsi_scan.c
+~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Scan a host to determine which (if any) devices are attached. The
+general scanning/probing algorithm is as follows, exceptions are made to
+it depending on device specific flags, compilation options, and global
+variable (boot or module load time) settings. A specific LUN is scanned
+via an INQUIRY command; if the LUN has a device attached, a scsi_device
+is allocated and setup for it. For every id of every channel on the
+given host, start by scanning LUN 0. Skip hosts that don't respond at
+all to a scan of LUN 0. Otherwise, if LUN 0 has a device attached,
+allocate and setup a scsi_device for it. If target is SCSI-3 or up,
+issue a REPORT LUN, and scan all of the LUNs returned by the REPORT LUN;
+else, sequentially scan LUNs up until some maximum is reached, or a LUN
+is seen that cannot have a device attached to it.
+
+.. kernel-doc:: drivers/scsi/scsi_scan.c
+ :internal:
+
+drivers/scsi/scsi_sysctl.c
+~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Set up the sysctl entry: "/dev/scsi/logging_level"
+(DEV_SCSI_LOGGING_LEVEL) which sets/returns scsi_logging_level.
+
+drivers/scsi/scsi_sysfs.c
+~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+SCSI sysfs interface routines.
+
+.. kernel-doc:: drivers/scsi/scsi_sysfs.c
+ :export:
+
+drivers/scsi/hosts.c
+~~~~~~~~~~~~~~~~~~~~
+
+mid to lowlevel SCSI driver interface
+
+.. kernel-doc:: drivers/scsi/hosts.c
+ :export:
+
+drivers/scsi/scsi_common.c
+~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+general support functions
+
+.. kernel-doc:: drivers/scsi/scsi_common.c
+ :export:
+
+Transport classes
+-----------------
+
+Transport classes are service libraries for drivers in the SCSI lower
+layer, which expose transport attributes in sysfs.
+
+Fibre Channel transport
+~~~~~~~~~~~~~~~~~~~~~~~
+
+The file drivers/scsi/scsi_transport_fc.c defines transport attributes
+for Fibre Channel.
+
+.. kernel-doc:: drivers/scsi/scsi_transport_fc.c
+ :export:
+
+iSCSI transport class
+~~~~~~~~~~~~~~~~~~~~~
+
+The file drivers/scsi/scsi_transport_iscsi.c defines transport
+attributes for the iSCSI class, which sends SCSI packets over TCP/IP
+connections.
+
+.. kernel-doc:: drivers/scsi/scsi_transport_iscsi.c
+ :export:
+
+Serial Attached SCSI (SAS) transport class
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+The file drivers/scsi/scsi_transport_sas.c defines transport
+attributes for Serial Attached SCSI, a variant of SATA aimed at large
+high-end systems.
+
+The SAS transport class contains common code to deal with SAS HBAs, an
+aproximated representation of SAS topologies in the driver model, and
+various sysfs attributes to expose these topologies and management
+interfaces to userspace.
+
+In addition to the basic SCSI core objects this transport class
+introduces two additional intermediate objects: The SAS PHY as
+represented by struct sas_phy defines an "outgoing" PHY on a SAS HBA or
+Expander, and the SAS remote PHY represented by struct sas_rphy defines
+an "incoming" PHY on a SAS Expander or end device. Note that this is
+purely a software concept, the underlying hardware for a PHY and a
+remote PHY is the exactly the same.
+
+There is no concept of a SAS port in this code, users can see what PHYs
+form a wide port based on the port_identifier attribute, which is the
+same for all PHYs in a port.
+
+.. kernel-doc:: drivers/scsi/scsi_transport_sas.c
+ :export:
+
+SATA transport class
+~~~~~~~~~~~~~~~~~~~~
+
+The SATA transport is handled by libata, which has its own book of
+documentation in this directory.
+
+Parallel SCSI (SPI) transport class
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+The file drivers/scsi/scsi_transport_spi.c defines transport
+attributes for traditional (fast/wide/ultra) SCSI busses.
+
+.. kernel-doc:: drivers/scsi/scsi_transport_spi.c
+ :export:
+
+SCSI RDMA (SRP) transport class
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+The file drivers/scsi/scsi_transport_srp.c defines transport
+attributes for SCSI over Remote Direct Memory Access.
+
+.. kernel-doc:: drivers/scsi/scsi_transport_srp.c
+ :export:
+
+SCSI lower layer
+================
+
+Host Bus Adapter transport types
+--------------------------------
+
+Many modern device controllers use the SCSI command set as a protocol to
+communicate with their devices through many different types of physical
+connections.
+
+In SCSI language a bus capable of carrying SCSI commands is called a
+"transport", and a controller connecting to such a bus is called a "host
+bus adapter" (HBA).
+
+Debug transport
+~~~~~~~~~~~~~~~
+
+The file drivers/scsi/scsi_debug.c simulates a host adapter with a
+variable number of disks (or disk like devices) attached, sharing a
+common amount of RAM. Does a lot of checking to make sure that we are
+not getting blocks mixed up, and panics the kernel if anything out of
+the ordinary is seen.
+
+To be more realistic, the simulated devices have the transport
+attributes of SAS disks.
+
+For documentation see http://sg.danny.cz/sg/sdebug26.html
+
+todo
+~~~~
+
+Parallel (fast/wide/ultra) SCSI, USB, SATA, SAS, Fibre Channel,
+FireWire, ATAPI devices, Infiniband, I2O, Parallel ports,
+netlink...