rdma_cap_ib_smi(9)

💖 NAME 💖

Okay bestie, this is the rdma_cap_ib_smi(9) page from the Kernel API Manual, and it's here to check if the port of a device provides an Infiniband Subnet Management Agent (SMA) on the Subnet Management Interface (SMI). 💅

✨ SYNOPSIS ✨

bool rdma_cap_ib_smi (const struct ib_device *device , u32 port_num );

🎀 ARGUMENTS 🎀

• device — Device to check. The device getting the look 👀
• port_num — Port number to check. Which port on that device gets checked 🫶

🦋 DESCRIPTION 🦋

Okay so every InfiniBand node is required to provide a Subnet Management Agent (SMA) that the subnet manager (SM) can access. Before the fabric is fully configured by the subnet manager, the SMA is accessed via a well-known interface called the Subnet Management Interface (SMI). This interface uses directed route packets to communicate with the SM, and that's how it gets around the chicken-and-egg problem: the SM needs to know what's on the fabric in order to configure the fabric, and it needs to configure the fabric in order to send packets to the devices on the fabric.

Directed route packets do not need the fabric fully configured in order to reach their destination. The SMI is the only method allowed to send directed route packets on an InfiniBand fabric — periodt. 👑

🌸 RETURN 🌸

It returns true if the port provides an SMI. That's the whole vibe check ✅

💖 SEE ALSO 💖

The SEE ALSO squad is huge, and every single one is invited — no skips, no cap:

• Kernel file ./include/rdma/ib_verbs.h
• 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_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)
• rdma_create_user_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)

Cute little sign-off: this page came from the source/version footer ./include/rdma, dated October 2026 — mwah 💋✨