efx_filter_insert_filter(9)

💖 efx_filter_insert_filter 💖

okay bestie, so this one lives in the Kernel API Manual, and it's literally the function that puts a new filter into your NIC (or swaps one out). let's get into it 🎀

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✨ SYNOPSIS ✨

s32 efx_filter_insert_filter (struct efx_nic *efx , struct
       efx_filter_spec *spec , bool replace_equal );

yes queen, that's the whole signature, don't @ me 🫶

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🌸 ARGUMENTS 🌸

• efx — the NIC you're inserting the filter into. like, the actual network card, bestie 💅
• spec — the specification for the filter. this is the blueprint for what you want ✨
• replace_equal — a flag for whether the specified filter may replace an existing filter with equal priority. so like, do you want to be polite and let it swap, or nah? 🙈

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💀 DESCRIPTION 💀

On success, this returns the filter ID. On failure, it returns a negative error code (sad girl hours 😭).

okay so here's the tea: if existing filters have equal match values to the new filter spec, then the new filter might replace them, or the function might just fail. it's giving "it depends." here's the play-by-play:

1. If the existing filters have lower priority, or replace_equal is set and they have equal priority, replace them. slay, you win 👑
2. If the existing filters have higher priority, return -EPERM. nope, not today, permission denied 🚫
3. If !efx_siena_filter_is_mc_recipient(spec), or the NIC does not support delivery to multiple recipients, return -EEXIST. already exists, sorry bestie 💀

This implies that filters for multiple multicast recipients must all be inserted with the same priority and replace_equal = false. no cap, that's literally the rule 🔥

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🦋 SEE ALSO 🦋

• Kernel file ./drivers/net/ethernet/sfc/siena/efx.h
• efx_filter_remove_id_safe(9)
• efx_filter_get_filter_safe(9)

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mwah 💖 that's the whole page. stay iconic, stay hydrated, and remember: -EPERM is just the kernel saying "not you, girl."

this little gem comes from ./drivers/net/ethernet/sfc/siena, dated October 2026 — go forth and filter responsibly, bestie 🧚✨