diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2024-09-26 09:45:36 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2024-09-26 09:45:36 -0700 |
| commit | 4965ddb166992557a25848049f1a70e56050eb7a (patch) | |
| tree | 530e827ac6016e87c000354d2a8de97001900c99 /Documentation/filesystems | |
| parent | 13882369ceb9b0953f9f5ff8563bbccfd80d0ffd (diff) | |
| parent | 68d4209158f43a558c5553ea95ab0c8975eab18c (diff) | |
| download | linux-4965ddb166992557a25848049f1a70e56050eb7a.tar.gz linux-4965ddb166992557a25848049f1a70e56050eb7a.tar.bz2 linux-4965ddb166992557a25848049f1a70e56050eb7a.zip | |
Merge tag 'usb-6.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb
Pull USB/Thunderbolt updates from Greg KH:
"Here is the large set of USB and Thunderbolt changes for 6.12-rc1.
Nothing "major" in here, except for a new 9p network gadget that has
been worked on for a long time (all of the needed acks are here)
Other than that, it's the usual set of:
- Thunderbolt / USB4 driver updates and additions for new hardware
- dwc3 driver updates and new features added
- xhci driver updates
- typec driver updates
- USB gadget updates and api additions to make some gadgets more
configurable by userspace
- dwc2 driver updates
- usb phy driver updates
- usbip feature additions
- other minor USB driver updates
All of these have been in linux-next for a long time with no reported
issues"
* tag 'usb-6.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb: (145 commits)
sub: cdns3: Use predefined PCI vendor ID constant
sub: cdns2: Use predefined PCI vendor ID constant
USB: misc: yurex: fix race between read and write
USB: misc: cypress_cy7c63: check for short transfer
USB: appledisplay: close race between probe and completion handler
USB: class: CDC-ACM: fix race between get_serial and set_serial
usb: r8a66597-hcd: make read-only const arrays static
usb: typec: ucsi: Fix busy loop on ASUS VivoBooks
usb: dwc3: rtk: Clean up error code in __get_dwc3_maximum_speed()
usb: storage: ene_ub6250: Fix right shift warnings
usb: roles: Improve the fix for a false positive recursive locking complaint
locking/mutex: Introduce mutex_init_with_key()
locking/mutex: Define mutex_init() once
net/9p/usbg: fix CONFIG_USB_GADGET dependency
usb: xhci: fix loss of data on Cadence xHC
usb: xHCI: add XHCI_RESET_ON_RESUME quirk for Phytium xHCI host
usb: dwc3: imx8mp: disable SS_CON and U3 wakeup for system sleep
usb: dwc3: imx8mp: add 2 software managed quirk properties for host mode
usb: host: xhci-plat: Parse xhci-missing_cas_quirk and apply quirk
usb: misc: onboard_usb_dev: add Microchip usb5744 SMBus programming support
...
Diffstat (limited to 'Documentation/filesystems')
| -rw-r--r-- | Documentation/filesystems/9p.rst | 58 |
1 files changed, 57 insertions, 1 deletions
diff --git a/Documentation/filesystems/9p.rst b/Documentation/filesystems/9p.rst index d270a0aa8d55..2bbf68b56b0d 100644 --- a/Documentation/filesystems/9p.rst +++ b/Documentation/filesystems/9p.rst @@ -48,11 +48,66 @@ For server running on QEMU host with virtio transport:: mount -t 9p -o trans=virtio <mount_tag> /mnt/9 -where mount_tag is the tag associated by the server to each of the exported +where mount_tag is the tag generated by the server to each of the exported mount points. Each 9P export is seen by the client as a virtio device with an associated "mount_tag" property. Available mount tags can be seen by reading /sys/bus/virtio/drivers/9pnet_virtio/virtio<n>/mount_tag files. +USBG Usage +========== + +To mount a 9p FS on a USB Host accessible via the gadget at runtime:: + + mount -t 9p -o trans=usbg,aname=/path/to/fs <device> /mnt/9 + +To mount a 9p FS on a USB Host accessible via the gadget as root filesystem:: + + root=<device> rootfstype=9p rootflags=trans=usbg,cache=loose,uname=root,access=0,dfltuid=0,dfltgid=0,aname=/path/to/rootfs + +where <device> is the tag associated by the usb gadget transport. +It is defined by the configfs instance name. + +USBG Example +============ + +The USB host exports a filesystem, while the gadget on the USB device +side makes it mountable. + +Diod (9pfs server) and the forwarder are on the development host, where +the root filesystem is actually stored. The gadget is initialized during +boot (or later) on the embedded board. Then the forwarder will find it +on the USB bus and start forwarding requests. + +In this case the 9p requests come from the device and are handled by the +host. The reason is that USB device ports are normally not available on +PCs, so a connection in the other direction would not work. + +When using the usbg transport, for now there is no native usb host +service capable to handle the requests from the gadget driver. For +this we have to use the extra python tool p9_fwd.py from tools/usb. + +Just start the 9pfs capable network server like diod/nfs-ganesha e.g.:: + + $ diod -f -n -d 0 -S -l 0.0.0.0:9999 -e $PWD + +Optionaly scan your bus if there are more then one usbg gadgets to find their path:: + + $ python $kernel_dir/tools/usb/p9_fwd.py list + + Bus | Addr | Manufacturer | Product | ID | Path + --- | ---- | ---------------- | ---------------- | --------- | ---- + 2 | 67 | unknown | unknown | 1d6b:0109 | 2-1.1.2 + 2 | 68 | unknown | unknown | 1d6b:0109 | 2-1.1.3 + +Then start the python transport:: + + $ python $kernel_dir/tools/usb/p9_fwd.py --path 2-1.1.2 connect -p 9999 + +After that the gadget driver can be used as described above. + +One use-case is to use it as an alternative to NFS root booting during +the development of embedded Linux devices. + Options ======= @@ -68,6 +123,7 @@ Options virtio connect to the next virtio channel available (from QEMU with trans_virtio module) rdma connect to a specified RDMA channel + usbg connect to a specified usb gadget channel ======== ============================================ uname=name user name to attempt mount as on the remote server. The |
