__iptfs_get_inner_mtu(9)

🌸 NAME 🌸

okay so bestie, welcome to the Kernel API Manual page for __iptfs_get_inner_mtu — yes, (9) is giving kernel API, iykyk 💅. This function returns the inner MTU with no fragmentation, periodt. ✨

🦋 SYNOPSIS 🦋

u32 __iptfs_get_inner_mtu (struct xfrm_state *x , int outer_mtu );

🎀 ARGUMENTS 🎀

• x — the xfrm state, bestie. literally the xfrm state.
• outer_mtu — the outer mtu, no cap. that’s the value it takes.

💖 RETURN 💖

It returns the correct MTU, taking into account the encap overhead ✨. That’s the whole return vibe.

🌈 SEE ALSO 🌈

The iptfs friend group lives in the kernel file ./net/xfrm/xfrm_iptfs.c — here’s the whole squad, all of them, no skips:

• IPTFS_DEFAULT_DROP_TIME_USECS(9)
• IPTFS_DEFAULT_REORDER_WINDOW(9)
• IPTFS_DEFAULT_INIT_DELAY_USECS(9)
• IPTFS_DEFAULT_MAX_QUEUE_SIZE(9)
• struct xfrm_iptfs_config(9)
• struct xfrm_iptfs_data(9)
• iptfs_alloc_skb(9)
• iptfs_skb_head_to_frag(9)
• struct iptfs_skb_frag_walk(9)
• iptfs_skb_prepare_frag_walk(9)
• iptfs_skb_can_add_frags(9)
• iptfs_skb_add_frags(9)
• iptfs_pskb_add_frags(9)
• iptfs_pskb_extract_seq(9)
• iptfs_input_save_runt(9)
• __iptfs_iphlen(9)
• __iptfs_iplen(9)
• iptfs_complete_inner_skb(9)
• iptfs_reassem_abort(9)
• iptfs_reassem_done(9)
• iptfs_reassem_cont(9)
• iptfs_input_ordered(9)
• iptfs_drop_timer(9)
• iptfs_input(9)
• iptfs_enqueue(9)
• iptfs_copy_create_frag(9)
• iptfs_copy_create_frags(9)
• iptfs_first_skb(9)
• iptfs_encap_add_ipv4(9)
• iptfs_encap_add_ipv6(9)
• iptfs_prepare_output(9)
• iptfs_get_inner_mtu(9)
• iptfs_user_init(9)

🌟 that’s the page, bestie! source/version: ./net/xfrm · date: October 2026 · manual page: __iptfs_get_inner_mtu(9) — slay and goodbye 💖