t4_alloc_vi(9)

💖 t4_alloc_vi(9) — the Kernel API Manual page you didn't know you needed 💖

okay so bestie, welcome to the Kernel API Manual entry for t4_alloc_vi(9), and trust me, this one's a whole thing but we're gonna get through it together 🫶 It's from the kernel-doc girlies in the networking corner, and ngl it's giving "I wrote this at 2am but I ate" energy.

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✨ NAME ✨

t4_alloc_vi — allocate a virtual interface 🌈

Like, it literally makes you a VI. that's the whole vibe.

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🎀 SYNOPSIS 🎀

int t4_alloc_vi (struct adapter *adap , unsigned int mbox , unsigned int
port , unsigned int pf , unsigned int vf , unsigned int nmac , u8 *mac ,
unsigned int *rss_size , u8 *vivld , u8 *vin );

that's a lot of arguments bestie, but we're gonna break every single one of them down below, no skipping 💅

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🦋 ARGUMENTS 🦋

• adap — the adapter, aka the whole reason we're here 🫶 this is your NIC's main character.
• mbox — the mailbox to use for the FW command. yep, you pick which mailbox you're sliding into. it's for the firmware, iykyk.
• port — the physical port associated with the VI. like which actual plug-in port this interface lives on ✨
• pf — the PF owning the VI. (physical function, for the uninitiated 💀)
• vf — the VF owning the VI. (that's the virtual function, and yes you need both of these, don't come for me)
• nmac — number of MAC addresses needed, and it's a range: 1 to 5. 1 to 5. don't try to be cute and pass 6 🙈
• mac — the MAC addresses of the VI.
• rss_size — size of the RSS table slice associated with this VI. (if you don't know what RSS is, just nod and know it's important 🎀)
• vivld — the destination to store the VI Valid value. yes, it's spelled like that, no I didn't make it up.
• vin — the destination to store the VIN value. (not the car kind 💀 it's the VI number)

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🔥 DESCRIPTION 🔥

okay so, the actual tea: t4_alloc_vi allocates a virtual interface for the given physical port. one adapter, one port, one freshly allocated VI, slay 💅

If mac is not NULL it contains the MAC addresses of the VI as assigned by FW. yes, FW (firmware) is picking your MACs for you like a matchmaker, and honestly, let it 👑

Now here's the part where you have to actually pay attention, bestie — mac should be large enough to hold nmac Ethernet addresses, they are stored consecutively so the space needed is nmac * 6 bytes. consecutively!! nmac * 6 bytes!! not a byte more, not a byte less, or you get to meet your friend undefined behaviour and that's not a cute look 🫶

It returns a negative error number or the non-negative VI id. so — bad news? negative error number, sorry girl 😭. good news? the non-negative VI id, and you can go live your life 🌸

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🌟 SEE ALSO 🌟

the source itself lives in the kernel file ./drivers/net/ethernet/chelsio/cxgb4/t4_hw.c — go read it if you're feeling brave 🧚

and now the mother of all SEE ALSO lists. I'm not skipping a single one, because these are all icons and they all reference (9), so here we go, buckle up:

t4_wait_op_done_val(9), t4_set_reg_field(9), t4_read_indirect(9), t4_write_indirect(9), t4_record_mbox(9), t4_wr_mbox_meat_timeout(9), t4_memory_rw_init(9), t4_memory_update_win(9), t4_memory_rw_residual(9), t4_memory_rw(9), t4_get_regs_len(9), t4_get_regs(9), t4_eeprom_ptov(9), t4_seeprom_wp(9), t4_get_raw_vpd_params(9), t4_get_vpd_params(9), t4_get_pfres(9), sf1_read(9), sf1_write(9), flash_wait_op(9), t4_read_flash(9), t4_write_flash(9), t4_get_fw_version(9), t4_get_bs_version(9), t4_get_tp_version(9), t4_get_exprom_version(9), t4_get_vpd_version(9), t4_get_scfg_version(9), t4_get_version_info(9), t4_dump_version_info(9), t4_check_fw_version(9), t4_flash_erase_sectors(9), t4_flash_cfg_addr(9), t4_load_fw(9), t4_phy_fw_ver(9), t4_load_phy_fw(9), t4_fwcache(9), fwcaps16_to_caps32(9), fwcaps32_to_caps16(9), t4_link_acaps(9), t4_link_l1cfg_core(9), t4_restart_aneg(9), t4_handle_intr_status(9), t4_slow_intr_handler(9), t4_intr_enable(9), t4_intr_disable(9), t4_config_rss_range(9), t4_config_glbl_rss(9), t4_config_vi_rss(9), t4_read_rss(9), t4_tp_fw_ldst_rw(9), t4_tp_indirect_rw(9), t4_tp_pio_read(9), t4_tp_pio_write(9), t4_tp_tm_pio_read(9), t4_tp_mib_read(9), t4_read_rss_key(9), t4_write_rss_key(9), t4_read_rss_pf_config(9), t4_read_rss_vf_config(9), t4_read_rss_pf_map(9), t4_read_rss_pf_mask(9), t4_tp_get_tcp_stats(9), t4_tp_get_err_stats(9), t4_tp_get_cpl_stats(9), t4_tp_get_rdma_stats(9), t4_get_fcoe_stats(9), t4_get_usm_stats(9), t4_read_mtu_tbl(9), t4_read_cong_tbl(9), t4_tp_wr_bits_indirect(9), init_cong_ctrl(9), t4_load_mtus(9), t4_get_chan_txrate(9), t4_set_trace_filter(9), t4_get_trace_filter(9), t4_pmtx_get_stats(9), t4_pmrx_get_stats(9), compute_mps_bg_map(9), t4_get_mps_bg_map(9), t4_get_tp_e2c_map(9), t4_get_tp_ch_map(9), t4_get_port_type_description(9), t4_get_port_stats_offset(9), t4_get_port_stats(9), t4_get_lb_stats(9), t4_mdio_rd(9), t4_mdio_wr(9), t4_sge_decode_idma_state(9), t4_sge_ctxt_flush(9), t4_read_sge_dbqtimers(9), t4_fw_hello(9), t4_fw_bye(9), t4_early_init(9), t4_fw_reset(9), t4_fw_halt(9), t4_fw_restart(9), t4_fw_upgrade(9), t4_fl_pkt_align(9), t4_fixup_host_params(9), t4_fw_initialize(9), t4_query_params_rw(9), t4_set_params_timeout(9), t4_set_params(9), t4_cfg_pfvf(9), t4_free_vi(9), t4_set_rxmode(9), t4_free_encap_mac_filt(9), t4_free_raw_mac_filt(9), t4_alloc_encap_mac_filt(9), t4_alloc_raw_mac_filt(9), t4_alloc_mac_filt(9), t4_free_mac_filt(9), t4_change_mac(9), t4_set_addr_hash(9), t4_enable_vi_params(9), t4_enable_vi(9), t4_enable_pi_params(9), t4_identify_port(9), t4_iq_stop(9), t4_iq_free(9), t4_eth_eq_free(9), t4_ctrl_eq_free(9), t4_ofld_eq_free(9), t4_link_down_rc_str(9), fwcap_to_fwspeed(9), lstatus_to_fwcap(9), t4_handle_get_port_info(9), t4_update_port_info(9), t4_get_link_params(9), t4_handle_fw_rpl(9), init_link_config(9), t4_prep_adapter(9), t4_shutdown_adapter(9), t4_bar2_sge_qregs(9), t4_init_devlog_params(9), t4_init_sge_params(9), t4_init_tp_params(9), t4_filter_field_shift(9), t4_init_portinfo(9), t4_read_cimq_cfg(9), t4_read_cim_ibq(9), t4_read_cim_obq(9), t4_cim_read(9), t4_cim_write(9), t4_cim_read_la(9), t4_tp_read_la(9), t4_idma_monitor_init(9), t4_idma_monitor(9), t4_load_cfg(9), t4_set_vf_mac_acl(9), t4_read_pace_tbl(9), t4_get_tx_sched(9), t4_sge_ctxt_rd_bd(9), t4_i2c_rd(9), t4_set_vlan_acl(9), modify_device_id(9), t4_load_boot(9), t4_flash_bootcfg_addr(9)

periodt. every single one of them, accounted for 💅

lowkey pro tip from your girl: t4_free_vi(9) is right there in that list for a reason — what the kernel allocates, the kernel must free. she's the icon, she's the moment 🙈

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alright bestie, that's the whole page ✨ this one's stamped ./drivers/net/ethernet/chelsio... and dated October 2026, and it came to you straight from the Kernel API Manual, page t4_alloc_vi(9). now go allocate a VI, but responsibly 💖🎀🦋