dma_fence_init64(9)

📦 version 7.3.1, in nixpkgs unstable

💖 dma_fence_init64(9) — kernel API manual, but make it make sense 💖

okay so bestie, welcome to the dma_fence_init64 page. this is kernel API manual territory, it's giving "you're in the driver layer now" energy, but I promise we're gonna get through it together 🫶

✨ NAME ✨

dma_fence_init64 — initialize a custom fence with 64-bit seqno support. periodt, that's the whole bit 👑

🌸 SYNOPSIS 🌸

void dma_fence_init64 (struct dma_fence *fence , const struct
       dma_fence_ops *ops , spinlock_t *lock , u64 context , u64 seqno );

like, yeah, five args, no cap. read on 💅

🎀 ARGUMENTS 🎀

  • fence — the fence you're initializing, bestie. this is the main character 🌟
  • ops — the dma_fence_ops that say what operations happen on this fence. it's giving instruction manual 📖
  • lock — an optional irqsafe spinlock to use for locking this fence. optional!! don't come for me 🙈
  • context — the execution context this fence is run on 🧚
  • seqno — a linear increasing sequence number for this context. it goes up, it doesn't go down, it's literally so consistent 💀

🦋 DESCRIPTION 🦋

so what does this actually do? it initializes an allocated fence. and here's the tea: the caller doesn't have to keep its refcount after committing with this fence — lowkey freeing. BUT. it will need to hold a refcount again if dma_fence_ops.enable_signaling gets called. so don't get too comfy 😭

context and seqno are there for easy comparison between fences, which means you can check which fence is later by simply using dma_fence_later. literally so convenient, ate 🔥

new users MUST NOT use external locks. like, not a suggestion, that's a MUST NOT. go read the documentation in dma_fence_init to understand the motives behind the legacy use cases — that's where the lore lives 📚

🌈 SEE ALSO 🌈

okay this list is long but I respect the hustle. go read these, iykyk:

✨ and that's the whole page, bestie ✨ this one lives over in ./drivers/dma-buf, dated October 2026 — go forth and init your fences responsibly, mwah 💋💅🫶

📦 where this page comes from