update_mapping(9)

💖 NAME 💖

Okay so bestie, welcome to update_mapping(9) from the Kernel API Manual ✨. This function is literally here to find and update any existing mapping for a given key, and it returns the value associated with the key in the pointer you provide. Iconic. 💅

✨ SYNOPSIS ✨

bool update_mapping (struct bucket *neighborhood , u64 key , void
       *new_value , bool update , void **old_value_ptr );

🎀 ARGUMENTS 🎀

Here's the cast, no cap:

• neighborhood — the first bucket in the neighborhood that would contain the search key. That's the whole vibe for this one.
• key — the key you're associating the new value with.
• new_value — the value to be associated with the key.
• update — whether to overwrite an existing value. Yes, that's the question this one answers, periodt.
• old_value_ptr — a pointer in which to store the old value (unmodified if no mapping was found). Important: it stays unmodified if no mapping was found.

🌸 RETURN 🌸

It returns true if the map contains a mapping for the key, and false if it does not. That's the vibe check: true = mapping exists, false = it does not. 🫶

🦋 SEE ALSO 🦋

Go stalk these next, bestie:

• Kernel file ./drivers/md/dm-vdo/int-map.c
• 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)
• find_or_make_vacancy(9)
• vdo_int_map_put(9)
• vdo_int_map_remove(9)

mwah 💋 — source/version: ./drivers/md/dm-vdo, dated October 2026, and this cutie is update_mapping(9). 🎀