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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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+===========================
+The Frame Buffer Device API
+===========================
+
+Last revised: June 21, 2011
+
+
+0. Introduction
+---------------
+
+This document describes the frame buffer API used by applications to interact
+with frame buffer devices. In-kernel APIs between device drivers and the frame
+buffer core are not described.
+
+Due to a lack of documentation in the original frame buffer API, drivers
+behaviours differ in subtle (and not so subtle) ways. This document describes
+the recommended API implementation, but applications should be prepared to
+deal with different behaviours.
+
+
+1. Capabilities
+---------------
+
+Device and driver capabilities are reported in the fixed screen information
+capabilities field::
+
+ struct fb_fix_screeninfo {
+ ...
+ __u16 capabilities; /* see FB_CAP_* */
+ ...
+ };
+
+Application should use those capabilities to find out what features they can
+expect from the device and driver.
+
+- FB_CAP_FOURCC
+
+The driver supports the four character code (FOURCC) based format setting API.
+When supported, formats are configured using a FOURCC instead of manually
+specifying color components layout.
+
+
+2. Types and visuals
+--------------------
+
+Pixels are stored in memory in hardware-dependent formats. Applications need
+to be aware of the pixel storage format in order to write image data to the
+frame buffer memory in the format expected by the hardware.
+
+Formats are described by frame buffer types and visuals. Some visuals require
+additional information, which are stored in the variable screen information
+bits_per_pixel, grayscale, red, green, blue and transp fields.
+
+Visuals describe how color information is encoded and assembled to create
+macropixels. Types describe how macropixels are stored in memory. The following
+types and visuals are supported.
+
+- FB_TYPE_PACKED_PIXELS
+
+Macropixels are stored contiguously in a single plane. If the number of bits
+per macropixel is not a multiple of 8, whether macropixels are padded to the
+next multiple of 8 bits or packed together into bytes depends on the visual.
+
+Padding at end of lines may be present and is then reported through the fixed
+screen information line_length field.
+
+- FB_TYPE_PLANES
+
+Macropixels are split across multiple planes. The number of planes is equal to
+the number of bits per macropixel, with plane i'th storing i'th bit from all
+macropixels.
+
+Planes are located contiguously in memory.
+
+- FB_TYPE_INTERLEAVED_PLANES
+
+Macropixels are split across multiple planes. The number of planes is equal to
+the number of bits per macropixel, with plane i'th storing i'th bit from all
+macropixels.
+
+Planes are interleaved in memory. The interleave factor, defined as the
+distance in bytes between the beginning of two consecutive interleaved blocks
+belonging to different planes, is stored in the fixed screen information
+type_aux field.
+
+- FB_TYPE_FOURCC
+
+Macropixels are stored in memory as described by the format FOURCC identifier
+stored in the variable screen information grayscale field.
+
+- FB_VISUAL_MONO01
+
+Pixels are black or white and stored on a number of bits (typically one)
+specified by the variable screen information bpp field.
+
+Black pixels are represented by all bits set to 1 and white pixels by all bits
+set to 0. When the number of bits per pixel is smaller than 8, several pixels
+are packed together in a byte.
+
+FB_VISUAL_MONO01 is currently used with FB_TYPE_PACKED_PIXELS only.
+
+- FB_VISUAL_MONO10
+
+Pixels are black or white and stored on a number of bits (typically one)
+specified by the variable screen information bpp field.
+
+Black pixels are represented by all bits set to 0 and white pixels by all bits
+set to 1. When the number of bits per pixel is smaller than 8, several pixels
+are packed together in a byte.
+
+FB_VISUAL_MONO01 is currently used with FB_TYPE_PACKED_PIXELS only.
+
+- FB_VISUAL_TRUECOLOR
+
+Pixels are broken into red, green and blue components, and each component
+indexes a read-only lookup table for the corresponding value. Lookup tables
+are device-dependent, and provide linear or non-linear ramps.
+
+Each component is stored in a macropixel according to the variable screen
+information red, green, blue and transp fields.
+
+- FB_VISUAL_PSEUDOCOLOR and FB_VISUAL_STATIC_PSEUDOCOLOR
+
+Pixel values are encoded as indices into a colormap that stores red, green and
+blue components. The colormap is read-only for FB_VISUAL_STATIC_PSEUDOCOLOR
+and read-write for FB_VISUAL_PSEUDOCOLOR.
+
+Each pixel value is stored in the number of bits reported by the variable
+screen information bits_per_pixel field.
+
+- FB_VISUAL_DIRECTCOLOR
+
+Pixels are broken into red, green and blue components, and each component
+indexes a programmable lookup table for the corresponding value.
+
+Each component is stored in a macropixel according to the variable screen
+information red, green, blue and transp fields.
+
+- FB_VISUAL_FOURCC
+
+Pixels are encoded and interpreted as described by the format FOURCC
+identifier stored in the variable screen information grayscale field.
+
+
+3. Screen information
+---------------------
+
+Screen information are queried by applications using the FBIOGET_FSCREENINFO
+and FBIOGET_VSCREENINFO ioctls. Those ioctls take a pointer to a
+fb_fix_screeninfo and fb_var_screeninfo structure respectively.
+
+struct fb_fix_screeninfo stores device independent unchangeable information
+about the frame buffer device and the current format. Those information can't
+be directly modified by applications, but can be changed by the driver when an
+application modifies the format::
+
+ struct fb_fix_screeninfo {
+ char id[16]; /* identification string eg "TT Builtin" */
+ unsigned long smem_start; /* Start of frame buffer mem */
+ /* (physical address) */
+ __u32 smem_len; /* Length of frame buffer mem */
+ __u32 type; /* see FB_TYPE_* */
+ __u32 type_aux; /* Interleave for interleaved Planes */
+ __u32 visual; /* see FB_VISUAL_* */
+ __u16 xpanstep; /* zero if no hardware panning */
+ __u16 ypanstep; /* zero if no hardware panning */
+ __u16 ywrapstep; /* zero if no hardware ywrap */
+ __u32 line_length; /* length of a line in bytes */
+ unsigned long mmio_start; /* Start of Memory Mapped I/O */
+ /* (physical address) */
+ __u32 mmio_len; /* Length of Memory Mapped I/O */
+ __u32 accel; /* Indicate to driver which */
+ /* specific chip/card we have */
+ __u16 capabilities; /* see FB_CAP_* */
+ __u16 reserved[2]; /* Reserved for future compatibility */
+ };
+
+struct fb_var_screeninfo stores device independent changeable information
+about a frame buffer device, its current format and video mode, as well as
+other miscellaneous parameters::
+
+ struct fb_var_screeninfo {
+ __u32 xres; /* visible resolution */
+ __u32 yres;
+ __u32 xres_virtual; /* virtual resolution */
+ __u32 yres_virtual;
+ __u32 xoffset; /* offset from virtual to visible */
+ __u32 yoffset; /* resolution */
+
+ __u32 bits_per_pixel; /* guess what */
+ __u32 grayscale; /* 0 = color, 1 = grayscale, */
+ /* >1 = FOURCC */
+ struct fb_bitfield red; /* bitfield in fb mem if true color, */
+ struct fb_bitfield green; /* else only length is significant */
+ struct fb_bitfield blue;
+ struct fb_bitfield transp; /* transparency */
+
+ __u32 nonstd; /* != 0 Non standard pixel format */
+
+ __u32 activate; /* see FB_ACTIVATE_* */
+
+ __u32 height; /* height of picture in mm */
+ __u32 width; /* width of picture in mm */
+
+ __u32 accel_flags; /* (OBSOLETE) see fb_info.flags */
+
+ /* Timing: All values in pixclocks, except pixclock (of course) */
+ __u32 pixclock; /* pixel clock in ps (pico seconds) */
+ __u32 left_margin; /* time from sync to picture */
+ __u32 right_margin; /* time from picture to sync */
+ __u32 upper_margin; /* time from sync to picture */
+ __u32 lower_margin;
+ __u32 hsync_len; /* length of horizontal sync */
+ __u32 vsync_len; /* length of vertical sync */
+ __u32 sync; /* see FB_SYNC_* */
+ __u32 vmode; /* see FB_VMODE_* */
+ __u32 rotate; /* angle we rotate counter clockwise */
+ __u32 colorspace; /* colorspace for FOURCC-based modes */
+ __u32 reserved[4]; /* Reserved for future compatibility */
+ };
+
+To modify variable information, applications call the FBIOPUT_VSCREENINFO
+ioctl with a pointer to a fb_var_screeninfo structure. If the call is
+successful, the driver will update the fixed screen information accordingly.
+
+Instead of filling the complete fb_var_screeninfo structure manually,
+applications should call the FBIOGET_VSCREENINFO ioctl and modify only the
+fields they care about.
+
+
+4. Format configuration
+-----------------------
+
+Frame buffer devices offer two ways to configure the frame buffer format: the
+legacy API and the FOURCC-based API.
+
+
+The legacy API has been the only frame buffer format configuration API for a
+long time and is thus widely used by application. It is the recommended API
+for applications when using RGB and grayscale formats, as well as legacy
+non-standard formats.
+
+To select a format, applications set the fb_var_screeninfo bits_per_pixel field
+to the desired frame buffer depth. Values up to 8 will usually map to
+monochrome, grayscale or pseudocolor visuals, although this is not required.
+
+- For grayscale formats, applications set the grayscale field to one. The red,
+ blue, green and transp fields must be set to 0 by applications and ignored by
+ drivers. Drivers must fill the red, blue and green offsets to 0 and lengths
+ to the bits_per_pixel value.
+
+- For pseudocolor formats, applications set the grayscale field to zero. The
+ red, blue, green and transp fields must be set to 0 by applications and
+ ignored by drivers. Drivers must fill the red, blue and green offsets to 0
+ and lengths to the bits_per_pixel value.
+
+- For truecolor and directcolor formats, applications set the grayscale field
+ to zero, and the red, blue, green and transp fields to describe the layout of
+ color components in memory::
+
+ struct fb_bitfield {
+ __u32 offset; /* beginning of bitfield */
+ __u32 length; /* length of bitfield */
+ __u32 msb_right; /* != 0 : Most significant bit is */
+ /* right */
+ };
+
+ Pixel values are bits_per_pixel wide and are split in non-overlapping red,
+ green, blue and alpha (transparency) components. Location and size of each
+ component in the pixel value are described by the fb_bitfield offset and
+ length fields. Offset are computed from the right.
+
+ Pixels are always stored in an integer number of bytes. If the number of
+ bits per pixel is not a multiple of 8, pixel values are padded to the next
+ multiple of 8 bits.
+
+Upon successful format configuration, drivers update the fb_fix_screeninfo
+type, visual and line_length fields depending on the selected format.
+
+
+The FOURCC-based API replaces format descriptions by four character codes
+(FOURCC). FOURCCs are abstract identifiers that uniquely define a format
+without explicitly describing it. This is the only API that supports YUV
+formats. Drivers are also encouraged to implement the FOURCC-based API for RGB
+and grayscale formats.
+
+Drivers that support the FOURCC-based API report this capability by setting
+the FB_CAP_FOURCC bit in the fb_fix_screeninfo capabilities field.
+
+FOURCC definitions are located in the linux/videodev2.h header. However, and
+despite starting with the V4L2_PIX_FMT_prefix, they are not restricted to V4L2
+and don't require usage of the V4L2 subsystem. FOURCC documentation is
+available in Documentation/userspace-api/media/v4l/pixfmt.rst.
+
+To select a format, applications set the grayscale field to the desired FOURCC.
+For YUV formats, they should also select the appropriate colorspace by setting
+the colorspace field to one of the colorspaces listed in linux/videodev2.h and
+documented in Documentation/userspace-api/media/v4l/colorspaces.rst.
+
+The red, green, blue and transp fields are not used with the FOURCC-based API.
+For forward compatibility reasons applications must zero those fields, and
+drivers must ignore them. Values other than 0 may get a meaning in future
+extensions.
+
+Upon successful format configuration, drivers update the fb_fix_screeninfo
+type, visual and line_length fields depending on the selected format. The type
+and visual fields are set to FB_TYPE_FOURCC and FB_VISUAL_FOURCC respectively.