UMASS(4)

okay bestie come closer 🫶 because we are talking about the umass page from the Kernel Interfaces Manual and honestly? it's giving essential 💾✨ no cap.

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🌸 NAME 🌸

umass — the USB Mass Storage Devices driver 🎀

✨ SYNOPSIS ✨

so you wanna bake this driver straight into your kernel? slay. drop these lines into your kernel configuration file, bestie:

device scbus
device usb
device umass

ORRRR, if you're more of a "load it as a module at boot time" kind of girlie, put this one line into loader.conf(5):

umass_load="YES"

both are valid, pick your fighter 💅

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🫶 DESCRIPTION 🫶

okay so here's the tea ☕ the umass driver provides support for Mass Storage devices that attach to the USB port. that's literally the whole point of it.

BUT. and this part matters. to actually use the umass driver, you need usb(4) configured in the kernel, plus one of uhci(4) or ohci(4) or ehci(4) or xhci(4). one of them. not all of them. choose wisely babe.

AND ALSO — because umass uses the SCSI subsystem and sometimes acts as a SCSI device, it requires da(4) and scbus(4) to be included in the kernel too. it's a whole squad situation and everybody's invited 🔥

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💖 EXAMPLES 💖

first up, the kernel config vibes:

device umass
device scbus
device da
device pass

^ that right there? that's how you Add the umass driver to the kernel.

and now, the rescan glow-up ✨:

camcontrol rescan 0:0:0
camcontrol rescan 0:0:1
camcontrol rescan 0:0:2
camcontrol rescan 0:0:3

this is how you Rescan all slots on a multi-slot flash reader, where the slots map to separate LUNs on a single SCSI ID. typically only the first slot will be enabled at boot time, which is lowkey annoying but that's the lore. also this whole example assumes that the flash reader is the first SCSI bus in the system and has 4 slots. iykyk 🧚

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👀 SEE ALSO 👀

go read these too, they're all iconic in their own way:

• cfumass(4), ehci(4), ohci(4), uhci(4), usb(4), xhci(4), camcontrol(8)

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👑 AUTHORS 👑

the umass driver was written by MAEKAWA Masahide <bishop@rr.iij4u.or.jp> and Nick Hibma <n_hibma@FreeBSD.org> 🫡

and this manual page was written by Nick Hibma <n_hibma@FreeBSD.org>. king behavior fr fr 👑

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and that's the whole page bestie!! this lil gem came to you from Debian, January 27, 2020 🎀 mwah, go plug in a flash drive and rescan something, you got this 💜