create_basic_memory_bitmaps(9)

💖 create_basic_memory_bitmaps(9) — the kernel API manual, but make it make sense 🎀

okay so bestie, welcome to the <bold>kernel API manual</bold> ✨ — this one's a create_basic_memory_bitmaps(9) situation and honestly? it's a little guy with one job and it does it well. let's get into it 🫶

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✨ NAME ✨

create_basic_memory_bitmaps — literally just: create bitmaps to hold basic page information. that's the whole vibe 💅

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🌸 SYNOPSIS 🌸

int create_basic_memory_bitmaps (void );

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🦋 ARGUMENTS 🦋

• void — no arguments. nothing. zero. the void is voiding 🙈

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🔥 DESCRIPTION 🔥

so here's the tea ☕ — this function creates the bitmaps you need for two things:

1. marking page frames that should not be saved
2. marking free page frames

and the <hotpink>forbidden_pages_map</hotpink> and <hotpink>free_pages_map</hotpink> pointers? they only get modified <bold>if everything goes well</bold> — that's not a flex, that's a whole design decision. the reasoning is that we don't` want the bits touched before both bitmaps are set up. like, no cap, both or nothing. all-or-nothing energy. iconic ✨

fr fr — the "only if everything goes well" part is the whole point. don't be out here expecting those pointers to move on a failure, because they won't. 💀

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👑 SEE ALSO 👑

here's the whole friend group 🫶 — and btw this all lives in the kernel file <purple>./kernel/power/snapshot.c</purple>:

• get_image_page(9)
• free_image_page(9)
• alloc_rtree_node(9)
• free_mem_extents(9)
• create_mem_extents(9)
• memory_bm_next_pfn(9)
• mark_nosave_pages(9)
• free_basic_memory_bitmaps(9)
• snapshot_additional_pages(9)
• count_free_highmem_pages(9)
• count_highmem_pages(9)
• count_data_pages(9)
• swsusp_free(9)
• preallocate_image_pages(9)
• free_unnecessary_pages(9)
• minimum_image_size(9)
• hibernate_preallocate_memory(9)
• pack_pfns(9)
• snapshot_read_next(9)
• unpack_orig_pfns(9)
• count_highmem_image_pages(9)
• prepare_highmem_image(9)
• copy_last_highmem_page(9)
• prepare_image(9)
• snapshot_write_next(9)
• restore_highmem(9)

go read them all, i'll wait 💜

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and that's the page babes 🌈 — brought to you by the <mint>./kernel/power</mint> directory, <yellow>October 2026</yellow> edition, still out here explaining create_basic_memory_bitmaps(9) to the masses. slay, stay hydrated, and remember: both bitmaps or nothing 💅💖🎀