STRUCT IO_TLB_AREA(9)

💅 struct io_tlb_area — the manual page, bestie

okay so this is page struct io_tlb_area(9) from the Kernel API Manual, and honestly? it's giving "small but mighty." let's get into it 🫶

✨ NAME ✨

struct io_tlb_area — the IO TLB memory area descriptor, aka the lil' vibes manager for one chunk of IO TLB memory 🌸

✨ SYNOPSIS ✨

struct io_tlb_area {
    unsigned long used;
    unsigned int index;
    spinlock_t lock;
 };

like, that's the whole struct. no cap, she's compact 💖

✨ Members ✨

• used — the number of used IO TLB block 🎀 (yes, exactly one block per this count, we're just reporting the facts)
• index — the slot index to start searching in this area for next round 🔍 literally the "where do we look next" bookmark
• lock — the lock to protect the above data structures in the map and unmap calls 👑 she's the bouncer for used and index, and she works in both the map and the unmap calls

✨ Description ✨

This is a single area with a single lock. that's it. that's the whole thing 💅 one area, one lock, main character energy, periodt ✨

🌈 SEE ALSO 🌈

Kernel file ./kernel/dma/swiotlb.c plus this whole friend group:

• struct io_tlb_slot(9)
• swiotlb_adjust_nareas(9)
• limit_nareas(9)
• add_mem_pool(9)
• alloc_dma_pages(9)
• swiotlb_alloc_tlb(9)
• swiotlb_free_tlb(9)
• swiotlb_alloc_pool(9)
• swiotlb_dyn_alloc(9)
• __swiotlb_find_pool(9)
• swiotlb_del_pool(9)
• swiotlb_dev_init(9)
• swiotlb_align_offset(9)
• swiotlb_search_pool_area(9)
• swiotlb_search_area(9)
• swiotlb_find_slots(9)
• mem_pool_used(9)
• mem_used(9)
• swiotlb_tbl_map_single(9)
• swiotlb_del_transient(9)
• is_swiotlb_allocated(9)
• default_swiotlb_base(9)
• default_swiotlb_limit(9)

bestie pls don't skip the SEE ALSO list, there are 23 entries and i counted them twice 😭 iykyk

okay and finally, the lil' sign-off: this one lives over in ./kernel/dma, it's dated October 2026, and the page title itself is struct io_tlb_area(9) — that's the whole footer, folded in with love 🦋💜 slay, go read the kernel source, mwah 🎀