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Commit | Line | Data |
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0f58f68b GH |
1 | |
2 | qemu usb storage emulation | |
3 | -------------------------- | |
4 | ||
34707333 | 5 | QEMU has three devices for usb storage emulation. |
0f58f68b GH |
6 | |
7 | Number one emulates the classic bulk-only transport protocol which is | |
8 | used by 99% of the usb sticks on the marked today and is called | |
9 | "usb-storage". Usage (hooking up to xhci, other host controllers work | |
10 | too): | |
11 | ||
12 | qemu ${other_vm_args} \ | |
13 | -drive if=none,id=stick,file=/path/to/file.img \ | |
14 | -device nec-usb-xhci,id=xhci \ | |
15 | -device usb-storage,bus=xhci.0,drive=stick | |
16 | ||
17 | ||
18 | Number two is the newer usb attached scsi transport. This one doesn't | |
19 | automagically create a scsi disk, so you have to explicitly attach one | |
20 | manually. Multiple logical units are supported. Here is an example | |
21 | with tree logical units: | |
22 | ||
23 | qemu ${other_vm_args} \ | |
24 | -drive if=none,id=uas-disk1,file=/path/to/file1.img \ | |
25 | -drive if=none,id=uas-disk2,file=/path/to/file2.img \ | |
26 | -drive if=none,id=uas-cdrom,media=cdrom,file=/path/to/image.iso \ | |
27 | -device nec-usb-xhci,id=xhci \ | |
28 | -device usb-uas,id=uas,bus=xhci.0 \ | |
29 | -device scsi-hd,bus=uas.0,scsi-id=0,lun=0,drive=uas-disk1 \ | |
30 | -device scsi-hd,bus=uas.0,scsi-id=0,lun=1,drive=uas-disk2 \ | |
31 | -device scsi-cd,bus=uas.0,scsi-id=0,lun=5,drive=uas-cdrom | |
32 | ||
33 | ||
34707333 GH |
34 | Number three emulates the classic bulk-only transport protocol too. |
35 | It's called "usb-bot". It shares most code with "usb-storage", and | |
36 | the guest will not be able to see the difference. The qemu command | |
37 | line interface is simliar to usb-uas though, i.e. no automatic scsi | |
38 | disk creation. It also features support for up to 16 LUNs. The LUN | |
39 | numbers must be continous, i.e. for three devices you must use 0+1+2. | |
40 | The 0+1+5 numbering from the "usb-uas" example isn't going to work | |
41 | with "usb-bot". | |
42 | ||
0f58f68b GH |
43 | enjoy, |
44 | Gerd | |
45 | ||
46 | -- | |
47 | Gerd Hoffmann <[email protected]> |