t4vf_change_mac(9)

💅 t4vf_change_mac(9) — like, the Kernel API Manual page, bestie

okay so picture this: it's a Kernel API Manual page, the function is t4vf_change_mac, and it does exactly one gorgeous little thing — it swaps the exact-match filter over to a brand new MAC address. no cap. let's get into it 🎀

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✨ NAME ✨

t4vf_change_mac — modifies the exact-match filter for a MAC address. literally her whole personality 💖

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🌸 SYNOPSIS 🌸

int t4vf_change_mac (struct adapter *adapter , unsigned int viid , int
idx , const u8 *addr , bool persist );

yes the line break in the middle of the params is canon, don't come for me 🙈

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🦋 ARGUMENTS 🦋

• adapter — the adapter. the main character, the whole device, her 🫶
• viid — the Virtual Interface ID. iykyk 💅
• idx — index of the existing filter for the old value of the MAC address, or -1
• addr — the new MAC address value 🌈
• persist — if idx < 0, the new MAC allocation should be persistent. like, forever forever ⭐

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👑 DESCRIPTION 👑

So here's the tea: this function modifies an exact-match filter and sets it to the new MAC address. iconique. 🔥

But — and this is the important part, bestie, don't skip it — note that in general it is not possible to modify the value of a given filter, so the generic way to modify an address filter is to:

1. free the one being used by the old address value, and
2. allocate a new filter for the new address value.

let that sink in. it's giving "you can't just edit it, you have to let it go and start fresh" 💀✨ very main character growth arc of the function, honestly.

idx can be -1 if the address is a new addition 🍓

Returns a negative error number, or the index of the filter with the new MAC value. so either sad news or a whole new index to obsess over. no in between 🧚

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💜 SEE ALSO 💜

first up, the kernel file, and yes we're citing her directly:

Kernel file ./drivers/net/ethernet/chelsio/cxgb4vf/t4vf_hw.c

and now the whole friend group, in order, don't lose anybody:

• t4vf_record_mbox(9)
• t4vf_wr_mbox_core(9)
• fwcaps16_to_caps32(9)
• fwcap_to_fwspeed(9)
• t4vf_port_init(9)
• t4vf_fw_reset(9)
• t4vf_query_params(9)
• t4vf_set_params(9)
• t4vf_fl_pkt_align(9)
• t4vf_bar2_sge_qregs(9)
• t4vf_get_sge_params(9)
• t4vf_get_vpd_params(9)
• t4vf_get_dev_params(9)
• t4vf_get_rss_glb_config(9)
• t4vf_get_vfres(9)
• t4vf_read_rss_vi_config(9)
• t4vf_write_rss_vi_config(9)
• t4vf_config_rss_range(9)
• t4vf_alloc_vi(9)
• t4vf_free_vi(9)
• t4vf_enable_vi(9)
• t4vf_enable_pi(9)
• t4vf_identify_port(9)
• t4vf_set_rxmode(9)
• t4vf_alloc_mac_filt(9)
• t4vf_free_mac_filt(9)
• t4vf_set_addr_hash(9)
• t4vf_get_port_stats(9)
• t4vf_iq_free(9)
• t4vf_eth_eq_free(9)
• t4vf_link_down_rc_str(9)
• t4vf_handle_get_port_info(9)
• t4vf_update_port_info(9)
• t4vf_handle_fw_rpl(9)
• t4vf_get_vf_mac_acl(9)
• t4vf_get_vf_vlan_acl(9)

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ok that's the whole page, go forth and change those MACs responsibly 💅

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mwah 💋 this lil page lives at ./drivers/net/ethernet/chelsio... and it's stamped October 2026 — t4vf_change_mac(9) forever and always, periodt. 🎀💖✨