aboutsummaryrefslogtreecommitdiff
path: root/Documentation/scsi/scsi-generic.rst
diff options
context:
space:
mode:
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 /Documentation/scsi/scsi-generic.rst
downloadlinux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz
linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.zip
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 'Documentation/scsi/scsi-generic.rst')
-rw-r--r--Documentation/scsi/scsi-generic.rst118
1 files changed, 118 insertions, 0 deletions
diff --git a/Documentation/scsi/scsi-generic.rst b/Documentation/scsi/scsi-generic.rst
new file mode 100644
index 000000000..258505e55
--- /dev/null
+++ b/Documentation/scsi/scsi-generic.rst
@@ -0,0 +1,118 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+=======================================
+Notes on Linux SCSI Generic (sg) driver
+=======================================
+
+ 20020126
+
+Introduction
+============
+The SCSI Generic driver (sg) is one of the four "high level" SCSI device
+drivers along with sd, st and sr (disk, tape and CDROM respectively). Sg
+is more generalized (but lower level) than its siblings and tends to be
+used on SCSI devices that don't fit into the already serviced categories.
+Thus sg is used for scanners, CD writers and reading audio CDs digitally
+amongst other things.
+
+Rather than document the driver's interface here, version information
+is provided plus pointers (i.e. URLs) where to find documentation
+and examples.
+
+
+Major versions of the sg driver
+===============================
+There are three major versions of sg found in the linux kernel (lk):
+ - sg version 1 (original) from 1992 to early 1999 (lk 2.2.5) .
+ It is based in the sg_header interface structure.
+ - sg version 2 from lk 2.2.6 in the 2.2 series. It is based on
+ an extended version of the sg_header interface structure.
+ - sg version 3 found in the lk 2.4 series (and the lk 2.5 series).
+ It adds the sg_io_hdr interface structure.
+
+
+Sg driver documentation
+=======================
+The most recent documentation of the sg driver is kept at the Linux
+Documentation Project's (LDP) site:
+
+- http://www.tldp.org/HOWTO/SCSI-Generic-HOWTO
+
+This describes the sg version 3 driver found in the lk 2.4 series.
+
+The LDP renders documents in single and multiple page HTML, postscript
+and pdf. This document can also be found at:
+
+- http://sg.danny.cz/sg/p/sg_v3_ho.html
+
+Documentation for the version 2 sg driver found in the lk 2.2 series can
+be found at http://sg.danny.cz/sg/. A larger version
+is at: http://sg.danny.cz/sg/p/scsi-generic_long.txt.
+
+The original documentation for the sg driver (prior to lk 2.2.6) can be
+found at http://www.torque.net/sg/p/original/SCSI-Programming-HOWTO.txt
+and in the LDP archives.
+
+A changelog with brief notes can be found in the
+/usr/src/linux/include/scsi/sg.h file. Note that the glibc maintainers copy
+and edit this file (removing its changelog for example) before placing it
+in /usr/include/scsi/sg.h . Driver debugging information and other notes
+can be found at the top of the /usr/src/linux/drivers/scsi/sg.c file.
+
+A more general description of the Linux SCSI subsystem of which sg is a
+part can be found at http://www.tldp.org/HOWTO/SCSI-2.4-HOWTO .
+
+
+Example code and utilities
+==========================
+There are two packages of sg utilities:
+
+ ========= ==========================================================
+ sg3_utils for the sg version 3 driver found in lk 2.4
+ sg_utils for the sg version 2 (and original) driver found in lk 2.2
+ and earlier
+ ========= ==========================================================
+
+Both packages will work in the lk 2.4 series however sg3_utils offers more
+capabilities. They can be found at: http://sg.danny.cz/sg/sg3_utils.html and
+freecode.com
+
+Another approach is to look at the applications that use the sg driver.
+These include cdrecord, cdparanoia, SANE and cdrdao.
+
+
+Mapping of Linux kernel versions to sg driver versions
+======================================================
+Here is a list of linux kernels in the 2.4 series that had new version
+of the sg driver:
+
+ - lk 2.4.0 : sg version 3.1.17
+ - lk 2.4.7 : sg version 3.1.19
+ - lk 2.4.10 : sg version 3.1.20 [#]_
+ - lk 2.4.17 : sg version 3.1.22
+
+.. [#] There were 3 changes to sg version 3.1.20 by third parties in the
+ next six linux kernel versions.
+
+For reference here is a list of linux kernels in the 2.2 series that had
+new version of the sg driver:
+
+ - lk 2.2.0 : original sg version [with no version number]
+ - lk 2.2.6 : sg version 2.1.31
+ - lk 2.2.8 : sg version 2.1.32
+ - lk 2.2.10 : sg version 2.1.34 [SG_GET_VERSION_NUM ioctl first appeared]
+ - lk 2.2.14 : sg version 2.1.36
+ - lk 2.2.16 : sg version 2.1.38
+ - lk 2.2.17 : sg version 2.1.39
+ - lk 2.2.20 : sg version 2.1.40
+
+The lk 2.5 development series has recently commenced and it currently
+contains sg version 3.5.23 which is functionally equivalent to sg
+version 3.1.22 found in lk 2.4.17.
+
+
+Douglas Gilbert
+
+26th January 2002
+
+dgilbert@interlog.com