dmam_alloc_attrs(9)

📦 version 7.3.1, in nixpkgs unstable

💅 dmam_alloc_attrs(9) — like, the managed version, bestie

okay so real talk, this is a page from the Kernel API Manual (yes, the kernel has a manual, she's iconic) and it's about one function: dmam_alloc_attrs. Buckle up 🎀

✨ NAME ✨

dmam_alloc_attrs — it's the managed dma_alloc_attrs(), fr fr. That's the whole vibe: same energy, but with cleanup handled for you 🫶

🌸 SYNOPSIS 🌸

void * dmam_alloc_attrs (struct device *dev , size_t size , dma_addr_t
*dma_handle , gfp_t gfp , unsigned long attrs );

like, five things in, one void * out. classic.

🦋 ARGUMENTS 🦋

  • dev — the device you're allocating that non_coherent memory for 👑
  • size — how big the allocation is, obviously 💅
  • dma_handle — an out argument, so it hands you back the allocated DMA handle ✨
  • gfp — the allocation flags, your standard gfp situation 🌈
  • attrs — flags living in the DMA_ATTR_* namespace, iykyk 🧚

💖 DESCRIPTION 💖

Managed dma_alloc_attrs. And the "managed" part is literally the whole point, bestie — memory you allocate with this function gets automatically released on driver detach. no cap. you don't have to remember to free it, the kernel's got you 😭🫶

⭐ RETURN ⭐

  • success → a pointer to the allocated memory, slay 💅
  • failure → NULL. that's it. that's the whole vibe check 💀

🔥 SEE ALSO 🔥

Kernel file ./kernel/dma/mapping.c, plus the whole friend group:

go read mapping.c if you wanna see how the sausage gets made, it's lowkey fascinating 🍓

and that's the page!! mwah 💋 this one's from ./kernel/dma, October 2026 edition — go off, kernel docs, you ate 🌟👑

📦 where this page comes from