STRUCT MEMBLOCK_REGION(9)

💅 struct memblock_region(9) — kernel API manual, bestie edition 🎀

Okay so this is a page from the Kernel API Manual, and today's main character is struct memblock_region. Pull up a chair, grab a strawberry, we're doing this. 🍓

✨ NAME ✨

struct memblock_region — the struct that represents a memory region. That's it, that's the whole vibe. It's giving "one little box that says where memory lives." 🦋

🌸 SYNOPSIS 🌸

struct memblock_region {
    phys_addr_t base;
    phys_addr_t size;
    enum memblock_flags flags;
  #ifdef CONFIG_NUMA;
    int nid;
  #endif;
 };

Like?? The cutest little struct?? Notice how nid is literally only in the group chat if CONFIG_NUMA is there — conditional membership, we love to see it. 👑

💖 Members 💖

• base — base address of the region. Where it starts, no cap. 📍
• size — size of the region. How much room it's taking up, iykyk. 📏
• flags — memory region attributes. All the little labels and traits it's carrying around. 🏷️
• nid — NUMA node id. Which node it's repping, basically. Only shows up when CONFIG_NUMA is enabled (see the synopsis, bestie — it's inside that #ifdef). 🌈

🔥 SEE ALSO 🔥

These are the friends, the mutuals, the whole crew. All of them, no skipping:

Kernel file ./include/linux/memblock.h — enum memblock_flags(9), struct memblock_type(9), struct memblock(9), for_each_physmem_range(9), __for_each_mem_range(9), __for_each_mem_range_rev(9), for_each_mem_range(9), for_each_mem_range_rev(9), for_each_reserved_mem_range(9), for_each_mem_pfn_range(9), for_each_free_mem_range(9), for_each_free_mem_range_reverse(9), memblock_set_current_limit(9), memblock_region_memory_base_pfn(9), memblock_region_memory_end_pfn(9), memblock_region_reserved_base_pfn(9), memblock_region_reserved_end_pfn(9), for_each_mem_region(9), for_each_reserved_mem_region(9)

That's the whole page, periodt. 💅 Signing off from ./include/linux, dated October 2026, and yes the footer still calls it struct memblock_region(9) because some things are iconic and never change. 🫶✨