snd_pcm_lib...locate_pages(9)

📦 version 7.3.1, in nixpkgs unstable

✨ snd_pcm_lib_preallocate_pages — the NAME bit ✨

Okay so bestie, welcome to the Kernel API Manual 💖 this is the page for snd_pcm_lib_preallocate_pages — it's literally pre-allocation for the given DMA type. That's the whole vibe. 🎀

🌸 SYNOPSIS 🌸

void snd_pcm_lib_preallocate_pages (struct snd_pcm_substream *substream
, int type , struct device *data , size_t size , size_t max );

Yep, that's the whole signature, no cap. Copy it exactly, don't get cute with it. 💅

🦋 ARGUMENTS 🦋

  • substream — the pcm substream instance 🫶 like, the actual thing you're preallocating for.
  • type — the DMA type, written as SNDRV_DMA_TYPE_* (star and all, that's the pattern, don't @ me).
  • data — DMA type dependent data. so it depends on the type, iykyk ✨
  • size — the requested pre-allocation size in bytes 📏
  • max — the max. allowed pre-allocation size 🔥 (yes, "max." with the little period in there, iconic)

💜 DESCRIPTION 💜

So what does it actually do? It does pre-allocation for the given DMA buffer type. That's it, that's the whole thing — it's giving "simple, focused, main character energy" 👑 no extra lore, just preallocate those pages for the DMA type you handed it.

⭐ SEE ALSO ⭐

The kernel file lives at ./sound/core/pcm_memory.c — go read it if you're feeling brave 🧚 and then check out the whole friend group:

All of them, every single one, so you can free stuff and manage buffers like a responsible queen 🍓

ngl if you preallocate you should also know how to free — that's literally why half of SEE ALSO exists 😭 go read those too, bestie.

and that's the page!! 💖✨🎀 this little gem lives in ./sound/core, dated October 2026, and it's filed under snd_pcm_lib...locate_pages(9) if you ever need to find it again 🦋💅🫶

📦 where this page comes from