ib_umem_odp_alloc_child(9)

💅 ib_umem_odp_alloc_child(9) 💅

okay bestie, welcome to the Kernel API Manual page for ib_umem_odp_alloc_child — section 9 energy, no cap ✨. This is literally the function that allocates a child ODP umem under an implicit parent ODP umem, and we're gonna get into it 🫶.

🎀 NAME 🎀

ib_umem_odp_alloc_child — allocate a child ODP umem under an implicit parent ODP umem 💖

✨ SYNOPSIS ✨

the whole function vibe is:

struct ib_umem_odp * ib_umem_odp_alloc_child (struct ib_umem_odp *root ,
unsigned long addr , size_t size , const struct
mmu_interval_notifier_ops *ops );

🌸 ARGUMENTS 🌸

• root — the parent umem that encloses the child, bestie. This one must be allocated using ib_alloc_implicit_odp_umem — like, mandatory mandatory 👑
• addr — the starting userspace VA. that's the address where the lil' userspace range begins 🧚
• size — the length of the userspace VA. how much of the address space we're talking about, fr fr 📏
• ops — MMU interval ops. currently only invalidate — that's the whole list, periodt 💅

⚠️ tiny but important heads up: root must be allocated using ib_alloc_implicit_odp_umem. not optional, not a suggestion, not a vibe check you can skip 😭

🦋 SEE ALSO 🦋

• Kernel file ./drivers/infiniband/core/umem_odp.c — go read the source, iykyk 👀
• ib_umem_odp_alloc_implicit(9)
• ib_umem_odp_get(9)
• ib_umem_odp_map_dma_and_lock(9)

byeeeee 🫶 this page lives under the source/version path ./drivers/infiniband/core, dated October 2026, and the whole thing is literally ib_umem_odp_alloc_child(9) — iconic, mwah 💅✨