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| author |  Linus Torvalds <torvalds@linux-foundation.org> | 2023-02-21 18:24:12 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2023-02-21 18:24:12 -0800 |
| commit | 5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch) | |
| tree | cc5c2d0a898769fd59549594fedb3ee6f84e59a0 /Documentation/usb/usbip_protocol.rst | |
| download | linux-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 '')
| -rw-r--r-- | Documentation/usb/usbip_protocol.rst | 452 |
1 files changed, 452 insertions, 0 deletions
diff --git a/Documentation/usb/usbip_protocol.rst b/Documentation/usb/usbip_protocol.rst new file mode 100644 index 000000000..adc158967 --- /dev/null +++ b/Documentation/usb/usbip_protocol.rst @@ -0,0 +1,452 @@ +=============== +USB/IP protocol +=============== + +Architecture +============ + +The USB/IP protocol follows a server/client architecture. The server exports the +USB devices and the clients import them. The device driver for the exported +USB device runs on the client machine. + +The client may ask for the list of the exported USB devices. To get the list the +client opens a TCP/IP connection to the server, and sends an OP_REQ_DEVLIST +packet on top of the TCP/IP connection (so the actual OP_REQ_DEVLIST may be sent +in one or more pieces at the low level transport layer). The server sends back +the OP_REP_DEVLIST packet which lists the exported USB devices. Finally the +TCP/IP connection is closed. + +:: + + virtual host controller usb host + "client" "server" + (imports USB devices) (exports USB devices) + | | + | OP_REQ_DEVLIST | + | ----------------------------------------------> | + | | + | OP_REP_DEVLIST | + | <---------------------------------------------- | + | | + +Once the client knows the list of exported USB devices it may decide to use one +of them. First the client opens a TCP/IP connection to the server and +sends an OP_REQ_IMPORT packet. The server replies with OP_REP_IMPORT. If the +import was successful the TCP/IP connection remains open and will be used +to transfer the URB traffic between the client and the server. The client may +send two types of packets: the USBIP_CMD_SUBMIT to submit an URB, and +USBIP_CMD_UNLINK to unlink a previously submitted URB. The answers of the +server may be USBIP_RET_SUBMIT and USBIP_RET_UNLINK respectively. + +:: + + virtual host controller usb host + "client" "server" + (imports USB devices) (exports USB devices) + | | + | OP_REQ_IMPORT | + | ----------------------------------------------> | + | | + | OP_REP_IMPORT | + | <---------------------------------------------- | + | | + | | + | USBIP_CMD_SUBMIT(seqnum = n) | + | ----------------------------------------------> | + | | + | USBIP_RET_SUBMIT(seqnum = n) | + | <---------------------------------------------- | + | . | + | : | + | | + | USBIP_CMD_SUBMIT(seqnum = m) | + | ----------------------------------------------> | + | | + | USBIP_CMD_SUBMIT(seqnum = m+1) | + | ----------------------------------------------> | + | | + | USBIP_CMD_SUBMIT(seqnum = m+2) | + | ----------------------------------------------> | + | | + | USBIP_RET_SUBMIT(seqnum = m) | + | <---------------------------------------------- | + | | + | USBIP_CMD_SUBMIT(seqnum = m+3) | + | ----------------------------------------------> | + | | + | USBIP_RET_SUBMIT(seqnum = m+1) | + | <---------------------------------------------- | + | | + | USBIP_CMD_SUBMIT(seqnum = m+4) | + | ----------------------------------------------> | + | | + | USBIP_RET_SUBMIT(seqnum = m+2) | + | <---------------------------------------------- | + | . | + | : | + +For UNLINK, note that after a successful USBIP_RET_UNLINK, the unlinked URB +submission would not have a corresponding USBIP_RET_SUBMIT (this is explained in +function stub_recv_cmd_unlink of drivers/usb/usbip/stub_rx.c). + +:: + + virtual host controller usb host + "client" "server" + (imports USB devices) (exports USB devices) + | | + | USBIP_CMD_SUBMIT(seqnum = p) | + | ----------------------------------------------> | + | | + | USBIP_CMD_UNLINK | + | (seqnum = p+1, unlink_seqnum = p) | + | ----------------------------------------------> | + | | + | USBIP_RET_UNLINK | + | (seqnum = p+1, status = -ECONNRESET) | + | <---------------------------------------------- | + | | + | Note: No USBIP_RET_SUBMIT(seqnum = p) | + | <--X---X---X---X---X---X---X---X---X---X---X--- | + | . | + | : | + | | + | USBIP_CMD_SUBMIT(seqnum = q) | + | ----------------------------------------------> | + | | + | USBIP_RET_SUBMIT(seqnum = q) | + | <---------------------------------------------- | + | | + | USBIP_CMD_UNLINK | + | (seqnum = q+1, unlink_seqnum = q) | + | ----------------------------------------------> | + | | + | USBIP_RET_UNLINK | + | (seqnum = q+1, status = 0) | + | <---------------------------------------------- | + | | + +The fields are in network (big endian) byte order meaning that the most significant +byte (MSB) is stored at the lowest address. + +Protocol Version +================ + +The documented USBIP version is v1.1.1. The binary representation of this +version in message headers is 0x0111. + +This is defined in tools/usb/usbip/configure.ac + +Message Format +============== + +OP_REQ_DEVLIST: + Retrieve the list of exported USB devices. + ++-----------+--------+------------+---------------------------------------------------+ +| Offset | Length | Value | Description | ++===========+========+============+===================================================+ +| 0 | 2 | | USBIP version | ++-----------+--------+------------+---------------------------------------------------+ +| 2 | 2 | 0x8005 | Command code: Retrieve the list of exported USB | +| | | | devices. | ++-----------+--------+------------+---------------------------------------------------+ +| 4 | 4 | 0x00000000 | Status: unused, shall be set to 0 | ++-----------+--------+------------+---------------------------------------------------+ + +OP_REP_DEVLIST: + Reply with the list of exported USB devices. + ++-----------+--------+------------+---------------------------------------------------+ +| Offset | Length | Value | Description | ++===========+========+============+===================================================+ +| 0 | 2 | | USBIP version | ++-----------+--------+------------+---------------------------------------------------+ +| 2 | 2 | 0x0005 | Reply code: The list of exported USB devices. | ++-----------+--------+------------+---------------------------------------------------+ +| 4 | 4 | 0x00000000 | Status: 0 for OK | ++-----------+--------+------------+---------------------------------------------------+ +| 8 | 4 | n | Number of exported devices: 0 means no exported | +| | | | devices. | ++-----------+--------+------------+---------------------------------------------------+ +| 0x0C | | | From now on the exported n devices are described, | +| | | | if any. If no devices are exported the message | +| | | | ends with the previous "number of exported | +| | | | devices" field. | ++-----------+--------+------------+---------------------------------------------------+ +| | 256 | | path: Path of the device on the host exporting the| +| | | | USB device, string closed with zero byte, e.g. | +| | | | "/sys/devices/pci0000:00/0000:00:1d.1/usb3/3-2" | +| | | | The unused bytes shall be filled with zero | +| | | | bytes. | ++-----------+--------+------------+---------------------------------------------------+ +| 0x10C | 32 | | busid: Bus ID of the exported device, string | +| | | | closed with zero byte, e.g. "3-2". The unused | +| | | | bytes shall be filled with zero bytes. | ++-----------+--------+------------+---------------------------------------------------+ +| 0x12C | 4 | | busnum | ++-----------+--------+------------+---------------------------------------------------+ +| 0x130 | 4 | | devnum | ++-----------+--------+------------+---------------------------------------------------+ +| 0x134 | 4 | | speed | ++-----------+--------+------------+---------------------------------------------------+ +| 0x138 | 2 | | idVendor | ++-----------+--------+------------+---------------------------------------------------+ +| 0x13A | 2 | | idProduct | ++-----------+--------+------------+---------------------------------------------------+ +| 0x13C | 2 | | bcdDevice | ++-----------+--------+------------+---------------------------------------------------+ +| 0x13E | 1 | | bDeviceClass | ++-----------+--------+------------+---------------------------------------------------+ +| 0x13F | 1 | | bDeviceSubClass | ++-----------+--------+------------+---------------------------------------------------+ +| 0x140 | 1 | | bDeviceProtocol | ++-----------+--------+------------+---------------------------------------------------+ +| 0x141 | 1 | | bConfigurationValue | ++-----------+--------+------------+---------------------------------------------------+ +| 0x142 | 1 | | bNumConfigurations | ++-----------+--------+------------+---------------------------------------------------+ +| 0x143 | 1 | | bNumInterfaces | ++-----------+--------+------------+---------------------------------------------------+ +| 0x144 | | m_0 | From now on each interface is described, all | +| | | | together bNumInterfaces times, with the following | +| | | | 4 fields: | ++-----------+--------+------------+---------------------------------------------------+ +| | 1 | | bInterfaceClass | ++-----------+--------+------------+---------------------------------------------------+ +| 0x145 | 1 | | bInterfaceSubClass | ++-----------+--------+------------+---------------------------------------------------+ +| 0x146 | 1 | | bInterfaceProtocol | ++-----------+--------+------------+---------------------------------------------------+ +| 0x147 | 1 | | padding byte for alignment, shall be set to zero | ++-----------+--------+------------+---------------------------------------------------+ +| 0xC + | | | The second exported USB device starts at i=1 | +| i*0x138 + | | | with the path field. | +| m_(i-1)*4 | | | | ++-----------+--------+------------+---------------------------------------------------+ + +OP_REQ_IMPORT: + Request to import (attach) a remote USB device. + ++-----------+--------+------------+---------------------------------------------------+ +| Offset | Length | Value | Description | ++===========+========+============+===================================================+ +| 0 | 2 | | USBIP version | ++-----------+--------+------------+---------------------------------------------------+ +| 2 | 2 | 0x8003 | Command code: import a remote USB device. | ++-----------+--------+------------+---------------------------------------------------+ +| 4 | 4 | 0x00000000 | Status: unused, shall be set to 0 | ++-----------+--------+------------+---------------------------------------------------+ +| 8 | 32 | | busid: the busid of the exported device on the | +| | | | remote host. The possible values are taken | +| | | | from the message field OP_REP_DEVLIST.busid. | +| | | | A string closed with zero, the unused bytes | +| | | | shall be filled with zeros. | ++-----------+--------+------------+---------------------------------------------------+ + +OP_REP_IMPORT: + Reply to import (attach) a remote USB device. + ++-----------+--------+------------+---------------------------------------------------+ +| Offset | Length | Value | Description | ++===========+========+============+===================================================+ +| 0 | 2 | | USBIP version | ++-----------+--------+------------+---------------------------------------------------+ +| 2 | 2 | 0x0003 | Reply code: Reply to import. | ++-----------+--------+------------+---------------------------------------------------+ +| 4 | 4 | 0x00000000 | Status: | +| | | | | +| | | | - 0 for OK | +| | | | - 1 for error | ++-----------+--------+------------+---------------------------------------------------+ +| 8 | | | From now on comes the details of the imported | +| | | | device, if the previous status field was OK (0), | +| | | | otherwise the reply ends with the status field. | ++-----------+--------+------------+---------------------------------------------------+ +| | 256 | | path: Path of the device on the host exporting the| +| | | | USB device, string closed with zero byte, e.g. | +| | | | "/sys/devices/pci0000:00/0000:00:1d.1/usb3/3-2" | +| | | | The unused bytes shall be filled with zero | +| | | | bytes. | ++-----------+--------+------------+---------------------------------------------------+ +| 0x108 | 32 | | busid: Bus ID of the exported device, string | +| | | | closed with zero byte, e.g. "3-2". The unused | +| | | | bytes shall be filled with zero bytes. | ++-----------+--------+------------+---------------------------------------------------+ +| 0x128 | 4 | | busnum | ++-----------+--------+------------+---------------------------------------------------+ +| 0x12C | 4 | | devnum | ++-----------+--------+------------+---------------------------------------------------+ +| 0x130 | 4 | | speed | ++-----------+--------+------------+---------------------------------------------------+ +| 0x134 | 2 | | idVendor | ++-----------+--------+------------+---------------------------------------------------+ +| 0x136 | 2 | | idProduct | ++-----------+--------+------------+---------------------------------------------------+ +| 0x138 | 2 | | bcdDevice | ++-----------+--------+------------+---------------------------------------------------+ +| 0x139 | 1 | | bDeviceClass | ++-----------+--------+------------+---------------------------------------------------+ +| 0x13A | 1 | | bDeviceSubClass | ++-----------+--------+------------+---------------------------------------------------+ +| 0x13B | 1 | | bDeviceProtocol | ++-----------+--------+------------+---------------------------------------------------+ +| 0x13C | 1 | | bConfigurationValue | ++-----------+--------+------------+---------------------------------------------------+ +| 0x13D | 1 | | bNumConfigurations | ++-----------+--------+------------+---------------------------------------------------+ +| 0x13E | 1 | | bNumInterfaces | ++-----------+--------+------------+---------------------------------------------------+ + +The following four commands have a common basic header called +'usbip_header_basic', and their headers, called 'usbip_header' (before +transfer_buffer payload), have the same length, therefore paddings are needed. + +usbip_header_basic: + ++-----------+--------+---------------------------------------------------+ +| Offset | Length | Description | ++===========+========+===================================================+ +| 0 | 4 | command | ++-----------+--------+---------------------------------------------------+ +| 4 | 4 | seqnum: sequential number that identifies requests| +| | | and corresponding responses; | +| | | incremented per connection | ++-----------+--------+---------------------------------------------------+ +| 8 | 4 | devid: specifies a remote USB device uniquely | +| | | instead of busnum and devnum; | +| | | for client (request), this value is | +| | | ((busnum << 16) | devnum); | +| | | for server (response), this shall be set to 0 | ++-----------+--------+---------------------------------------------------+ +| 0xC | 4 | direction: | +| | | | +| | | - 0: USBIP_DIR_OUT | +| | | - 1: USBIP_DIR_IN | +| | | | +| | | only used by client, for server this shall be 0 | ++-----------+--------+---------------------------------------------------+ +| 0x10 | 4 | ep: endpoint number | +| | | only used by client, for server this shall be 0; | +| | | for UNLINK, this shall be 0 | ++-----------+--------+---------------------------------------------------+ + +USBIP_CMD_SUBMIT: + Submit an URB + ++-----------+--------+---------------------------------------------------+ +| Offset | Length | Description | ++===========+========+===================================================+ +| 0 | 20 | usbip_header_basic, 'command' shall be 0x00000001 | ++-----------+--------+---------------------------------------------------+ +| 0x14 | 4 | transfer_flags: possible values depend on the | +| | | USBIP_URB transfer_flags. | +| | | Refer to include/uapi/linux/usbip.h and | +| | | Documentation/driver-api/usb/URB.rst. | +| | | Refer to usbip_pack_cmd_submit() and | +| | | tweak_transfer_flags() in drivers/usb/usbip/ | +| | | usbip_common.c. | ++-----------+--------+---------------------------------------------------+ +| 0x18 | 4 | transfer_buffer_length: | +| | | use URB transfer_buffer_length | ++-----------+--------+---------------------------------------------------+ +| 0x1C | 4 | start_frame: use URB start_frame; | +| | | initial frame for ISO transfer; | +| | | shall be set to 0 if not ISO transfer | ++-----------+--------+---------------------------------------------------+ +| 0x20 | 4 | number_of_packets: number of ISO packets; | +| | | shall be set to 0xffffffff if not ISO transfer | ++-----------+--------+---------------------------------------------------+ +| 0x24 | 4 | interval: maximum time for the request on the | +| | | server-side host controller | ++-----------+--------+---------------------------------------------------+ +| 0x28 | 8 | setup: data bytes for USB setup, filled with | +| | | zeros if not used. | ++-----------+--------+---------------------------------------------------+ +| 0x30 | n | transfer_buffer. | +| | | If direction is USBIP_DIR_OUT then n equals | +| | | transfer_buffer_length; otherwise n equals 0. | +| | | For ISO transfers the padding between each ISO | +| | | packets is not transmitted. | ++-----------+--------+---------------------------------------------------+ +| 0x30+n | m | iso_packet_descriptor | ++-----------+--------+---------------------------------------------------+ + +USBIP_RET_SUBMIT: + Reply for submitting an URB + ++-----------+--------+---------------------------------------------------+ +| Offset | Length | Description | ++===========+========+===================================================+ +| 0 | 20 | usbip_header_basic, 'command' shall be 0x00000003 | ++-----------+--------+---------------------------------------------------+ +| 0x14 | 4 | status: zero for successful URB transaction, | +| | | otherwise some kind of error happened. | ++-----------+--------+---------------------------------------------------+ +| 0x18 | 4 | actual_length: number of URB data bytes; | +| | | use URB actual_length | ++-----------+--------+---------------------------------------------------+ +| 0x1C | 4 | start_frame: use URB start_frame; | +| | | initial frame for ISO transfer; | +| | | shall be set to 0 if not ISO transfer | ++-----------+--------+---------------------------------------------------+ +| 0x20 | 4 | number_of_packets: number of ISO packets; | +| | | shall be set to 0xffffffff if not ISO transfer | ++-----------+--------+---------------------------------------------------+ +| 0x24 | 4 | error_count | ++-----------+--------+---------------------------------------------------+ +| 0x28 | 8 | padding, shall be set to 0 | ++-----------+--------+---------------------------------------------------+ +| 0x30 | n | transfer_buffer. | +| | | If direction is USBIP_DIR_IN then n equals | +| | | actual_length; otherwise n equals 0. | +| | | For ISO transfers the padding between each ISO | +| | | packets is not transmitted. | ++-----------+--------+---------------------------------------------------+ +| 0x30+n | m | iso_packet_descriptor | ++-----------+--------+---------------------------------------------------+ + +USBIP_CMD_UNLINK: + Unlink an URB + ++-----------+--------+---------------------------------------------------+ +| Offset | Length | Description | ++===========+========+===================================================+ +| 0 | 20 | usbip_header_basic, 'command' shall be 0x00000002 | ++-----------+--------+---------------------------------------------------+ +| 0x14 | 4 | unlink_seqnum, of the SUBMIT request to unlink | ++-----------+--------+---------------------------------------------------+ +| 0x18 | 24 | padding, shall be set to 0 | ++-----------+--------+---------------------------------------------------+ + +USBIP_RET_UNLINK: + Reply for URB unlink + ++-----------+--------+---------------------------------------------------+ +| Offset | Length | Description | ++===========+========+===================================================+ +| 0 | 20 | usbip_header_basic, 'command' shall be 0x00000004 | ++-----------+--------+---------------------------------------------------+ +| 0x14 | 4 | status: This is similar to the status of | +| | | USBIP_RET_SUBMIT (share the same memory offset). | +| | | When UNLINK is successful, status is -ECONNRESET; | +| | | when USBIP_CMD_UNLINK is after USBIP_RET_SUBMIT | +| | | status is 0 | ++-----------+--------+---------------------------------------------------+ +| 0x18 | 24 | padding, shall be set to 0 | ++-----------+--------+---------------------------------------------------+ + +EXAMPLE +======= + + The following data is captured from wire with Human Interface Devices (HID) + payload + +:: + + CmdIntrIN: 00000001 00000d05 0001000f 00000001 00000001 00000200 00000040 ffffffff 00000000 00000004 00000000 00000000 + CmdIntrOUT: 00000001 00000d06 0001000f 00000000 00000001 00000000 00000040 ffffffff 00000000 00000004 00000000 00000000 + ffffffff860008a784ce5ae212376300000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000 + RetIntrOut: 00000003 00000d06 00000000 00000000 00000000 00000000 00000040 ffffffff 00000000 00000000 00000000 00000000 + RetIntrIn: 00000003 00000d05 00000000 00000000 00000000 00000000 00000040 ffffffff 00000000 00000000 00000000 00000000 + ffffffff860011a784ce5ae2123763612891b1020100000400000000000000000000000000000000000000000000000000000000000000000000000000000000 |