STRUCT CLEAN_WALK(9)

✨ struct clean_walk(9) ✨

okay so bestie, welcome to the struct clean_walk(9) page 💅 this is your girl's guide to... well, a private struct, so it's kinda exclusive, iykyk. It lives in the Kernel API Manual and it's the private struct for the clean_record_pte function. Private! main character energy only 🎀

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🌸 NAME 🌸

struct clean_walk — the private struct for the clean_record_pte function. not for the general public, bestie, it's giving backstage pass 🎟️

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🦋 SYNOPSIS 🦋

struct clean_walk {
    struct wp_walk base;
    pgoff_t bitmap_pgoff;
    unsigned long *bitmap;
    pgoff_t start;
    pgoff_t end;
 };

yeah that's the whole vibe. five members, zero drama 💀 (well, one tiny bit of drama — see start and end below).

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🧚 Members 🧚

okay let's meet the cast, one by one, no skipping fr fr 👑

• base — the struct wp_walk we derive from. it's the parent it's inheriting from, the nepo baby of the struct 💖
• bitmap_pgoff — the address_space page offset of the first bit in bitmap. like, bit zero's home address 🏠
• bitmap — a bitmap with one bit for each page offset in the address_space range covered. one bit per page offset, so it stays lowkey tiny and slay ✨
• start — the address_space page offset of the first modified pte, relative to bitmap_pgoff. relative!! not absolute!! don't come for me, that's just what it is 🙈
• end — the address_space page offset of the last modified pte, relative to bitmap_pgoff. same deal, also relative, stay mad about it 🫶

real talk: start and end are both measured relative to bitmap_pgoff, so if you read them as absolute offsets you're gonna have a bad time. no cap 💀

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👀 SEE ALSO 👀

go touch some other pages bestie, they're all in the kernel file ./mm/mapping_dirty_helpers.c:

• struct wp_walk(9)
• wp_pte(9)
• clean_record_pte(9)
• wp_shared_mapping_range(9)
• clean_record_shared_mapping_range(9)

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and that's the whole page, you ate that 🍓💜 this came out of ./mm and it's dated October 2026 — so go forth, read your pte's, and remember: private structs are private for a reason. mwah 🌈⭐