vdo_int_map_put(9)

💖 vdo_int_map_put(9) 💖

okay so real talk, this is a page straight out of the Kernel API Manual — yes, that Kernel API Manual — and it's all about vdo_int_map_put. Buckle up bestie, we're mapping integers to values and it's gonna slay. 🌸

---

✨ NAME ✨

vdo_int_map_put — try to associate a value with an integer. that's it. that's the whole vibe. 🎀

---

🌈 SYNOPSIS 🌈

int vdo_int_map_put (struct int_map *map , u64 key , void *new_value ,
bool update , void **old_value_ptr );

look at her. five args. main character energy fr. 👑

---

🦋 ARGUMENTS 🦋

• map — the int_map you're trying to modify. she's the one getting the glow-up. 💅
• key — the key you wanna associate the new value with. like, this is the lock and the value is the key but also the key is the key. iykyk. 🔑
• new_value — the value that's getting associated with the key. the new kid. the fresh face. 🌟
• update — whether to overwrite an existing value. like, do we barge in and redecorate, or do we respect what's already there? true = barge in. 😤
• old_value_ptr — a pointer where you stash either the old value (if the key was already mapped) or NULL if the map didn't contain the key. and here's the cute part: you can pass NULL for this whole thing if you literally do not care about the old value. not me being unbothered. 🙈

---

💜 DESCRIPTION 💜

So the mission — should you choose to accept it — is to try to associate a value (a pointer, babe, it's a pointer) with an integer in an int_map. 🫶

If the map already contains a mapping for the provided key, the old value only gets replaced with the specified value if update is true. Otherwise the old one just sits there, unbothered, thriving. 💀

And in either case, the old value is returned. every single time. no exceptions, no cap. 💯

But if the map does not already contain a value for the specified key? then the new value gets added regardless of the value of update. like update doesn't even get a vote in that situation. she's irrelevant. iconic. 🔥

---

⭐ RETURN ⭐

VDO_SUCCESS or an error code. that's the whole return section. short and sweet, just how we like it. ✨

---

🧚 SEE ALSO 🧚

Kernel file ./drivers/md/dm-vdo/int-map.c — go read the source, bestie, it's giving lore. 📖

• Introduction(9)
• struct bucket(9)
• struct int_map(9)
• mix(9)
• hash_key(9)
• allocate_buckets(9)
• vdo_int_map_create(9)
• vdo_int_map_free(9)
• vdo_int_map_size(9)
• dereference_hop(9)
• insert_in_hop_list(9)
• select_bucket(9)
• search_hop_list(9)
• vdo_int_map_get(9)
• resize_buckets(9)
• find_empty_bucket(9)
• move_empty_bucket(9)
• update_mapping(9)
• find_or_make_vacancy(9)
• vdo_int_map_remove(9)

literally the whole friend group. go say hi. 👋💖

---

okay and finally, the credits moment — this page lives in ./drivers/md/dm-vdo, dated October 2026, and it's page vdo_int_map_put(9) of the Kernel API Manual. mwah. 💋 thanks for coming to my ted talk, go map some integers responsibly. 🍓🌈