rdma_user_mmap_entry_put(9)

📦 version 7.3.1, in nixpkgs unstable

💅 rdma_user_mmap_entry_put(9) — or, "letting go of your mmap entry, bestie"

okay so first things first: this is a page from the Kernel API Manual, section 9, and the whole vibe is reference counting for mmap entries in RDMA. she's short, she's sweet, she's the cleanup half of a get/put pair. let's get into it 🫶

✨ NAME ✨

rdma_user_mmap_entry_put — drop reference to the mmap entry

like, you're done with it, so you put it down. respectfully. 🔥

🌸 SYNOPSIS 🌸

void rdma_user_mmap_entry_put (struct rdma_user_mmap_entry *entry );

yep that's the whole signature, no cap. returns void, which honestly is such a mood — she does the work and doesn't need to report back.

🎀 ARGUMENTS 🎀

  • entry — an entry in the mmap_xa. that's it, that's the whole parameter. one (1) entry, from the mmap_xa. 💖

🦋 DESCRIPTION 🦋

okay so here's the tea ☕ — this function gets called when the mapping is closed, if it was an io mapping, or when the driver is simply done with the entry for some other reason. either way, she's the one who handles the goodbye.

the rule is: you call her after rdma_user_mmap_entry_get was called, and once entry is no longer needed. that's the order, bestie, don't skip it 🙈

and what does she actually do? she will erase the entry and free it if its refcnt reaches zero. so if you were the last one holding on — she cleans it all up. if not, she just drops your reference and lets the others finish their little moment. iconic behavior, honestly. 👑

lowkey important: this is the put to the get. you don't just vibe in there and call her out of nowhere — she expects the get to have happened already. iykyk 💀

⭐ SEE ALSO ⭐

the whole friend group fr fr — go read them too, they're all in the same little kernel-file neighborhood 🧚

and that's the page, bestie!! this one lives in ./drivers/infiniband/core, from the Kernel API Manual, dated October 2026 — go forth and put your entries responsibly 💜✨🎀

📦 where this page comes from