snd_dma_allo...ges_fallback(9)

📦 version 7.3.1, in nixpkgs unstable

💅 snd_dma_allo...ges_fallback(9) — like, the whole glow-up

okay so bestie, welcome to the Kernel API Manual entry for snd_dma_allo...ges_fallback 🎀 yes the name is truncated with dots and yes that's just how the man page wears it, we don't question the fit. she's a section 9 function, she allocates buffer areas, and she has a fallback plan, which honestly is main character energy. ✨

🌸 NAME 🌸

snd_dma_alloc_pages_fallback — allocate the buffer area according to the given type, with fallback 🫶

like, she tries, and if it doesn't work she tries again smaller. resilience icon.

✨ SYNOPSIS ✨

int snd_dma_alloc_pages_fallback (int type , struct device *device ,
       size_t size , struct snd_dma_buffer *dmab );

she returns an int, she takes four things, and she is not sorry about the line wrapping. 💅

🦋 ARGUMENTS 🦋

  • type — the DMA buffer type. it's giving "which flavor of allocator do you want" 🍓
  • device — the device pointer, aka the device she's doing all this for.
  • size — the buffer size to allocate. the dream size, before reality steps in (more on that in a sec 😭).
  • dmab — the buffer allocation record where the allocated data gets stored. she's the receipt, keep her safe 🧾

💖 DESCRIPTION 💖

so here's the vibe: she calls the memory-allocator function that matches the corresponding buffer type. that's the first move, straightforward, no drama.

but when there's no space left, she does not just give up and cry in the group chat. instead, this function reduces the size and tries to allocate again 🔥 persistent queen behavior.

and the size that actually got allocated? that gets stored in the res_size argument. important detail, no cap — you asked for size, but what you got is whatever res_size says. 💀

ngl this is the whole point of the "fallback" in the name, bestie. she negotiated down and still came home with a buffer. 👑

⭐ RETURN ⭐

  • Zero — the buffer with the given size got allocated successfully. slay. 🎉
  • otherwise — a negative value on error. not slay, but at least she told you. 😭

🌈 SEE ALSO 🌈

Kernel file ./sound/core/memalloc.c — plus the whole friend group, fr fr:

and that's the page!! 🧚 sources live in ./sound/core, dated October 2026, and it's filed under snd_dma_allo...ges_fallback(9) in case you need to find her again. mwah 💜 iykyk.

📦 where this page comes from