ib_umem_get_cq_buf_or_va(9)

💅 NAME 💅

okay bestie, welcome to the Kernel API Manual page for ib_umem_get_cq_buf_or_va(9) ✨ She is literally here to pin a CQ buffer umem with UHW VA fallback. No cap.

🎀 SYNOPSIS 🎀

the signature, untouched, because we respect the code:

       struct ib_umem * ib_umem_get_cq_buf_or_va (struct ib_device *device ,
       const struct uverbs_attr_bundle *attrs , u64 addr , size_t size , int
       access );

🌸 ARGUMENTS 🌸

• device — the IB device, bestie.
• attrs — the uverbs attribute bundle. it may be NULL, and that's valid.
• addr — the UHW user VA used when no per-command attribute matched.
• size — okay so on the attr / legacy paths, this is the minimum required umem length validated post-pin; on the VA fallback path, it's the length to pin. yes, she does double duty, keep reading.
• access — the IB access flags.

🦋 DESCRIPTION 🦋

So it's like ib_umem_get_cq_buf, but it pins addr/size when neither the UMEM attribute nor the legacy CQ buffer attributes are supplied. That's the whole glow-up ✨

Also: see ib_umem_get_attr_or_va for the note on size's dual role and the migration path for drivers that would distinguish a user-supplied length from a driver-computed minimum. iykyk.

🔥 RETURN 🔥

On success you get a caller-owned umem 🫶 On error it's ERR_PTR(...), so handle it with care 😭

🌈 SEE ALSO 🌈

• Kernel file ./drivers/infiniband/core/umem.c
• ib_umem_find_best_pgsz(9)
• ib_umem_get_desc(9)
• ib_umem_get_attr(9)
• ib_umem_get_attr_or_va(9)
• ib_umem_get_cq_buf(9)
• ib_umem_release(9)

mwah 💋 this page comes from the ./drivers/infiniband/core source, October 2026 edition — slay, go read the kernel code responsibly 👑