ib_dma_map_sg(9)

💅 NAME 💅

ib_dma_map_sg — okay so real talk, this is the Kernel API Manual entry that maps a scatter/gather list to DMA addresses ✨ like it takes your lil' list of memory chunks and hands back the DMA-address version, and honestly? iconic behavior 💖

🎀 SYNOPSIS 🎀

int ib_dma_map_sg (struct ib_device *dev , struct scatterlist *sg , int
nents , enum dma_data_direction direction );

🌸 ARGUMENTS 🌸

• dev — bestie, this is the device: the one the DMA addresses are gonna be created for 🫶 no device, no mapping, no slay.
• sg — the array of scatter/gather entries, aka the actual pile of chunks we're mapping 💅
• nents — the number of scatter/gather entries in that array 🔢 literally just how many of them there are.
• direction — the direction of the DMA 🧭 which way the data's vibing, iykyk.

🦋 SEE ALSO 🦋

Okay so this section is a whole friend group, and we're not leaving a single one of them out 👑 they all live in the kernel file ./include/rdma/ib_verbs.h, and here's the entire squad, in order, no cap:

• 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), 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_unmap_sg(9), ib_dma_max_seg_size(9), ib_dma_sync_single_for_cpu(9), ib_dma_sync_single_for_device(9) 🫶 (yes these are the DMA ones, we're literally in the same family, family dinner fr)
• 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)

no cap, that's genuinely the whole list — don't skip any of them, they all matter 💀

okay that's the whole page, bestie, we ate and left zero crumbs 🍓 this lil' entry comes to you from ./include/rdma, dated October 2026, and it's ib_dma_map_sg(9) signing off — mwah 💋✨