ib_dma_max_seg_size(9)

ib_dma_max_seg_size 💅

okay bestie, so this one lives in the Kernel API Manual (that's the 9 in ib_dma_max_seg_size(9), iykyk) and it's honestly a little one-pager — like, five lines of actual content — but it's important content, so let's go 🫶

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🌸 NAME 🌸

ib_dma_max_seg_size — literally just returns the size limit of a single DMA transfer. that's the whole job. she's a one-trick pony and she ATE 💅

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✨ SYNOPSIS ✨

unsigned int ib_dma_max_seg_size (struct ib_device *dev );

so you hand her a device pointer and she hands you back an unsigned int. cute, quick, no drama 🔥

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🎀 ARGUMENTS 🎀

• dev — the device you want to query, bestie. that's it. just the one. she's not asking for your whole life story 💖

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🦋 DESCRIPTION 🦋

the value she gives you back? it's a size in bytes ✨ that's the entire description. no hidden lore, no secret extra behavior, no "but actually—". it's a size. in bytes. periodt.

ngl the manpage itself is this short, so don't go looking for extra vibes that aren't there 🙈 she said what she said.

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👑 SEE ALSO 👑

like, everyone is in the group chat for this one 😭 the whole Kernel file ./include/rdma/ib_verbs.h crew, in the exact order they showed up:

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_map_sg(9), ib_dma_unmap_sg(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 I said. the whole friend group. go say hi to all of them 🌈

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and that's the page, bestie 🧚 — mega shoutout to the source over at ./include/rdma and the version stamped October 2026 ⭐ you're all caught up, go forth and query your seg sizes responsibly 💜