rdma_create_user_ah(9)

🌸 rdma_create_user_ah(9) 🌸

okay so bestie, welcome to the Kernel API Manual section for rdma_create_user_ah — like, yes, this is the kernel docs, and yes, we're gonna make it cute. sit down, grab a strawberry drink 🍓, let's go.

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✨ NAME ✨

rdma_create_user_ah — makes an address handle for the address vector you hand it 💅 and, lowkey the slay part, it resolves the destination MAC address for a ah attribute that's of RoCE type. no cap.

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✨ SYNOPSIS ✨

struct ib_ah * rdma_create_user_ah (struct ib_pd *pd , struct
rdma_ah_attr *ah_attr , struct ib_udata *udata );

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✨ ARGUMENTS ✨

• pd — the protection domain that's associated with the address handle 🫶 like, this AH belongs to this PD, that's the vibe.
• ah_attr — the attributes of the address vector ✨ the actual "where are we going" info.
• udata — pointer to the user's input/output buffer info that the provider driver needs 👑 it's giving "provider driver supply drop."

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✨ DESCRIPTION ✨

so it returns 0 on success, and it returns the appropriate error code when there's an error 💀 that's the whole summary, bestie.

the address handle itself is used to reference a local or a global destination in all UD QP post sends 🔥 like every single one, it's main character energy for UD send paths.

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✨ SEE ALSO ✨

okay this list is long and honestly iconic, so let's give it the respect it deserves 🌈 — the kernel file ./include/rdma/ib_verbs.h plus:

struct rdma_stat_desc(9), struct rdma_hw_stats(9), ib_rate_to_mult(9), ib_rate_to_mbps(9), ib_port_attr_to_speed_info(9), enum ib_mr_type(9), struct ib_mr_status(9), mult_to_ib_rate(9), struct ib_udata(9), struct rdma_netdev(9), struct ib_device_ops(9), ib_get_client_data(9), ib_modify_qp_is_ok(9), rdma_cap_ib_switch(9), rdma_start_port(9), rdma_for_each_port(9), rdma_end_port(9), rdma_cap_ib_mad(9), rdma_cap_opa_mad(9), rdma_cap_ib_smi(9), rdma_cap_ib_cm(9), rdma_cap_iw_cm(9), rdma_cap_ib_sa(9), rdma_cap_ib_mcast(9), rdma_cap_af_ib(9), rdma_cap_eth_ah(9), rdma_cap_opa_ah(9), rdma_max_mad_size(9), rdma_cap_roce_gid_table(9), rdma_core_cap_opa_port(9), rdma_mtu_enum_to_int(9), rdma_mtu_from_attr(9), ib_alloc_pd(9), ib_dealloc_pd(9), rdma_create_ah(9), ib_get_gids_from_rdma_hdr(9), ib_get_rdma_header_version(9), ib_init_ah_attr_from_wc(9), ib_create_ah_from_wc(9), rdma_modify_ah(9), rdma_query_ah(9), rdma_destroy_ah_user(9), rdma_destroy_ah(9), ib_modify_srq(9), ib_query_srq(9), ib_destroy_srq_user(9), ib_destroy_srq(9), ib_post_srq_recv(9), ib_create_qp(9), ib_modify_qp_with_udata(9), ib_modify_qp(9), ib_query_qp(9), ib_destroy_qp(9), ib_open_qp(9), ib_close_qp(9), ib_post_send(9), ib_post_recv(9), ib_alloc_cq_any(9), rdma_set_cq_moderation(9), ib_destroy_cq_user(9), ib_destroy_cq(9), ib_poll_cq(9), ib_req_notify_cq(9), ib_virt_dma_to_ptr(9), ib_virt_dma_to_page(9), ib_dma_mapping_error(9), ib_dma_map_single(9), ib_dma_unmap_single(9), ib_dma_map_page(9), ib_dma_unmap_page(9), ib_dma_map_bvec(9), ib_dma_unmap_bvec(9), ib_dma_map_sgtable_attrs(9), ib_dma_map_sg(9), ib_dma_unmap_sg(9), ib_dma_max_seg_size(9), ib_dma_sync_single_for_cpu(9), ib_dma_sync_single_for_device(9), ib_dereg_mr_user(9), ib_dereg_mr(9), ib_update_fast_reg_key(9), ib_inc_rkey(9), ib_attach_mcast(9), ib_detach_mcast(9), ib_check_mr_status(9), ib_device_try_get(9), rdma_ah_find_type(9), ib_lid_cpu16(9), ib_lid_be16(9), rdma_roce_rescan_device(9), rdma_device_to_ibdev(9), ibdev_to_node(9), rdma_device_to_drv_device(9), rdma_flow_label_to_udp_sport(9), rdma_calc_flow_label(9), rdma_get_udp_sport(9)

like… she read every adjacent page in ib_verbs.h, and honestly? obsessed. 🦋

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💖 also real quick: everything above is exactly what the page says, no extra lore, no invented behaviour. if you need the actual rules, go read the references, bestie, i'm just the vibe translator. 🧚

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and that's the page, periodt. 🎀 this one lives under ./include/rdma, from the October 2026 drop of the Kernel API Manual — mwah, go forth and create those address handles 💅👑