__iavf_chk_linearize(9)

💖 __iavf_chk_linearize — the kernel API manual, but make it make sense 💖

okay bestie, welcome to the __iavf_chk_linearize(9) page from the Kernel API Manual ✨ this is the little helper that checks if there are more than 8 buffers per packet, and honestly it's giving "tiny function, huge responsibility" energy 👑

---

✨ NAME ✨

__iavf_chk_linearize — check if there are more than 8 buffers per packet 🎀

---

🌸 SYNOPSIS 🌸

bool __iavf_chk_linearize (struct sk_buff *skb );

like literally that's it, that's the whole call ✨

---

🦋 ARGUMENTS 🦋

• skb — the send buffer 💌 (yes that's the whole description, she's a woman of few words and we respect it)

---

💅 NOTE 💅 (read this one, i'm begging)

okay so here's the tea, and it's important 🫖

Our HW can't DMA more than 8 buffers to build a packet on the wire, so we need to figure out the cases where we need to linearize the skb. no cap. 8 buffers max, that's the whole vibe check. 😭

For TSO we need to count the TSO header and segment payload separately. As such we need to check cases where we have 7 fragments or more, because we can potentially require 9 DMA transactions:

1. 1 for the TSO header 🎀
2. 1 for the segment payload in the first descriptor 🎀
3. another 7 for the fragments 💀

so yeah, 7 fragments + the header + the payload = we already blew past 8 and it's not even close, hence this function existing. the math is mathing ✨

---

👑 SEE ALSO 👑

the kernel file, bestie — go read the source if you want the full lore 📖

• ./drivers/net/ethernet/intel/iavf/iavf_txrx.c

and the whole friend group 💜:

• iavf_is_descriptor_done(9)
• iavf_unmap_and_free_tx_resource(9)
• iavf_clean_tx_ring(9)
• iavf_free_tx_resources(9)
• iavf_get_tx_pending(9)
• iavf_force_wb(9)
• iavf_detect_recover_hung(9)
• iavf_clean_tx_irq(9)
• iavf_enable_wb_on_itr(9)
• iavf_update_itr(9)
• iavf_setup_tx_descriptors(9)
• iavf_clean_rx_ring(9)
• iavf_free_rx_resources(9)
• iavf_setup_rx_descriptors(9)
• iavf_release_rx_desc(9)
• iavf_receive_skb(9)
• iavf_alloc_rx_buffers(9)
• iavf_rx_csum(9)
• iavf_legacy_rx_csum(9)
• iavf_flex_rx_csum(9)
• iavf_legacy_rx_hash(9)
• iavf_flex_rx_hash(9)
• iavf_flex_rx_tstamp(9)
• iavf_process_skb_fields(9)
• iavf_cleanup_headers(9)
• iavf_add_rx_frag(9)
• iavf_build_skb(9)
• iavf_is_non_eop(9)
• iavf_extract_legacy_rx_fields(9)
• iavf_extract_flex_rx_fields(9)
• iavf_clean_rx_irq(9)
• iavf_update_enable_itr(9)
• iavf_napi_poll(9)
• iavf_tx_prepare_vlan_flags(9)
• iavf_tso(9)
• iavf_tx_enable_csum(9)
• iavf_create_tx_ctx(9)
• __iavf_maybe_stop_tx(9)
• iavf_tx_map(9)
• iavf_xmit_frame_ring(9)
• iavf_xmit_frame(9)

---

reminder bestie: the hardware cap is real, and the 7-fragments threshold is real, don't come for me, come for the DMA engine 💀

okay that's the page!! this one came from ./drivers/net/ethernet/intel/iavf, dated October 2026, and it's signed __iavf_chk_linearize(9) — slay, go linearize responsibly 🧚💖🌸