__mmc_claim_host(9)

📦 version 7.3.1, in nixpkgs unstable

💅 __mmc_claim_host — like, the exclusive-host-claiming one 💅

okay so this is a page from the Kernel API Manual bestie, and it's all about __mmc_claim_host — the function that goes "this host is MINE" exclusively. no sharing, no splitting, periodt. 👑

✨ NAME ✨

__mmc_claim_host — exclusively claim a host 🫶

🌸 SYNOPSIS 🌸

int __mmc_claim_host (struct mmc_host *host , struct mmc_ctx *ctx ,
       atomic_t *abort );

literally that's the whole signature, no cap ✨

🎀 ARGUMENTS 🎀

  • host — the mmc host you're claiming, bestie. this is the actual thing you want 💖
  • ctx — the context that claims the host. or NULL, in which case the default context gets used instead (lowkey convenient ngl) 🙈
  • abort — whether or not the operation should be aborted. yes it's a whole "should we bail" situation 🏃‍♀️

🦋 DESCRIPTION 🦋

so you're claiming a host for a set of operations. main character energy only, one at a time 🎀

here's the tea though: if abort is non-null and dereferences to a non-zero value, then this will return prematurely with that non-zero value without acquiring the lock. like it just leaves, no lock, nothing. 💀

otherwise? it returns zero with the lock held. so like, zero means you got it, you're holding the lock, slay 💅

fr fr double-check that abort situation before you go assuming you've got the lock — a premature return means no lock at all, and that's the kind of thing that ruins your whole day 😭

🌈 SEE ALSO 🌈

the kernel file ./drivers/mmc/core/core.c says hi, and so do all these besties:

go read them, they're iconic too 👑

okay that's the whole page, mwah 💖 this one came out of ./drivers/mmc/core, dated October 2026, and it's filed under __mmc_claim_host(9) — take care of her, she holds locks 🫶✨

📦 where this page comes from