tso_dma_map_init(9)

💖 NAME 💖

Okay bestie, welcome to the tso_dma_map_init(9) page from the Kernel API Manual 🌸. This one is all about DMA-mapping your GSO payload regions, and she is lowkey iconic.

tso_dma_map_init — DMA-map GSO payload regions. Periodt 💅.

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✨ SYNOPSIS ✨

int tso_dma_map_init (struct tso_dma_map *map , struct device *dev ,
       const struct sk_buff *skb , unsigned int hdr_len );

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🎀 ARGUMENTS 🎀

• map — the <italic>map</italic> struct you’re initializing. Main character energy fr fr.
• dev — the device used for DMA mapping. She’s doing the mapping work 🫶.
• skb — the GSO skb, no cap.
• hdr_len — per-segment header length, in bytes. Count ‘em carefully bestie 🔥.

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🦋 DESCRIPTION 🦋

Okay so here’s the tea: this function DMA-maps the linear payload — that’s the part after the headers, iykyk — and all the frags 💖.

It prefers the DMA IOVA API, which gives you one contiguous mapping and one IOTLB sync. Slay. But if IOVA isn’t available, it falls back to per-region dma_map_phys like a responsible icon 🌈.

Then it positions the iterator at byte 0 of the payload. Very demure, very mindful ✨.

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🌟 RETURN 🌟

• 0 — success! We love to see it 💜.
• -ENOMEM — DMA mapping failure 😭. The partial mappings are cleaned up internally, so no messy leftovers, thank goodness 🎀.

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👑 SEE ALSO 👑

• The kernel file ./net/core/tso.c 📁
• tso_dma_map_cleanup(9)
• tso_dma_map_count(9)
• tso_dma_map_next(9)

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mwah 💋 — this cutie came from ./net/core, dated October 2026 🎀✨