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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
+
+Layout
+------
+
+The layout of a standard block group is approximately as follows (each
+of these fields is discussed in a separate section below):
+
+.. list-table::
+ :widths: 1 1 1 1 1 1 1 1
+ :header-rows: 1
+
+ * - Group 0 Padding
+ - ext4 Super Block
+ - Group Descriptors
+ - Reserved GDT Blocks
+ - Data Block Bitmap
+ - inode Bitmap
+ - inode Table
+ - Data Blocks
+ * - 1024 bytes
+ - 1 block
+ - many blocks
+ - many blocks
+ - 1 block
+ - 1 block
+ - many blocks
+ - many more blocks
+
+For the special case of block group 0, the first 1024 bytes are unused,
+to allow for the installation of x86 boot sectors and other oddities.
+The superblock will start at offset 1024 bytes, whichever block that
+happens to be (usually 0). However, if for some reason the block size =
+1024, then block 0 is marked in use and the superblock goes in block 1.
+For all other block groups, there is no padding.
+
+The ext4 driver primarily works with the superblock and the group
+descriptors that are found in block group 0. Redundant copies of the
+superblock and group descriptors are written to some of the block groups
+across the disk in case the beginning of the disk gets trashed, though
+not all block groups necessarily host a redundant copy (see following
+paragraph for more details). If the group does not have a redundant
+copy, the block group begins with the data block bitmap. Note also that
+when the filesystem is freshly formatted, mkfs will allocate “reserve
+GDT block” space after the block group descriptors and before the start
+of the block bitmaps to allow for future expansion of the filesystem. By
+default, a filesystem is allowed to increase in size by a factor of
+1024x over the original filesystem size.
+
+The location of the inode table is given by ``grp.bg_inode_table_*``. It
+is continuous range of blocks large enough to contain
+``sb.s_inodes_per_group * sb.s_inode_size`` bytes.
+
+As for the ordering of items in a block group, it is generally
+established that the super block and the group descriptor table, if
+present, will be at the beginning of the block group. The bitmaps and
+the inode table can be anywhere, and it is quite possible for the
+bitmaps to come after the inode table, or for both to be in different
+groups (flex_bg). Leftover space is used for file data blocks, indirect
+block maps, extent tree blocks, and extended attributes.
+
+Flexible Block Groups
+---------------------
+
+Starting in ext4, there is a new feature called flexible block groups
+(flex_bg). In a flex_bg, several block groups are tied together as one
+logical block group; the bitmap spaces and the inode table space in the
+first block group of the flex_bg are expanded to include the bitmaps
+and inode tables of all other block groups in the flex_bg. For example,
+if the flex_bg size is 4, then group 0 will contain (in order) the
+superblock, group descriptors, data block bitmaps for groups 0-3, inode
+bitmaps for groups 0-3, inode tables for groups 0-3, and the remaining
+space in group 0 is for file data. The effect of this is to group the
+block group metadata close together for faster loading, and to enable
+large files to be continuous on disk. Backup copies of the superblock
+and group descriptors are always at the beginning of block groups, even
+if flex_bg is enabled. The number of block groups that make up a
+flex_bg is given by 2 ^ ``sb.s_log_groups_per_flex``.
+
+Meta Block Groups
+-----------------
+
+Without the option META_BG, for safety concerns, all block group
+descriptors copies are kept in the first block group. Given the default
+128MiB(2^27 bytes) block group size and 64-byte group descriptors, ext4
+can have at most 2^27/64 = 2^21 block groups. This limits the entire
+filesystem size to 2^21 * 2^27 = 2^48bytes or 256TiB.
+
+The solution to this problem is to use the metablock group feature
+(META_BG), which is already in ext3 for all 2.6 releases. With the
+META_BG feature, ext4 filesystems are partitioned into many metablock
+groups. Each metablock group is a cluster of block groups whose group
+descriptor structures can be stored in a single disk block. For ext4
+filesystems with 4 KB block size, a single metablock group partition
+includes 64 block groups, or 8 GiB of disk space. The metablock group
+feature moves the location of the group descriptors from the congested
+first block group of the whole filesystem into the first group of each
+metablock group itself. The backups are in the second and last group of
+each metablock group. This increases the 2^21 maximum block groups limit
+to the hard limit 2^32, allowing support for a 512PiB filesystem.
+
+The change in the filesystem format replaces the current scheme where
+the superblock is followed by a variable-length set of block group
+descriptors. Instead, the superblock and a single block group descriptor
+block is placed at the beginning of the first, second, and last block
+groups in a meta-block group. A meta-block group is a collection of
+block groups which can be described by a single block group descriptor
+block. Since the size of the block group descriptor structure is 32
+bytes, a meta-block group contains 32 block groups for filesystems with
+a 1KB block size, and 128 block groups for filesystems with a 4KB
+blocksize. Filesystems can either be created using this new block group
+descriptor layout, or existing filesystems can be resized on-line, and
+the field s_first_meta_bg in the superblock will indicate the first
+block group using this new layout.
+
+Please see an important note about ``BLOCK_UNINIT`` in the section about
+block and inode bitmaps.
+
+Lazy Block Group Initialization
+-------------------------------
+
+A new feature for ext4 are three block group descriptor flags that
+enable mkfs to skip initializing other parts of the block group
+metadata. Specifically, the INODE_UNINIT and BLOCK_UNINIT flags mean
+that the inode and block bitmaps for that group can be calculated and
+therefore the on-disk bitmap blocks are not initialized. This is
+generally the case for an empty block group or a block group containing
+only fixed-location block group metadata. The INODE_ZEROED flag means
+that the inode table has been initialized; mkfs will unset this flag and
+rely on the kernel to initialize the inode tables in the background.
+
+By not writing zeroes to the bitmaps and inode table, mkfs time is
+reduced considerably. Note the feature flag is RO_COMPAT_GDT_CSUM,
+but the dumpe2fs output prints this as “uninit_bg”. They are the same
+thing.