find_next_res(9)

💅 find_next_res(9)

okay so bestie, this one lives in the Kernel API Manual and it's literally the resource-tree scavenger hunt function. let's get into it 🫶

---

✨ NAME ✨

find_next_res — finds the lowest resource that covers part of [@start..@end]. yes, the lowest, it's giving "first one in line gets it" energy 💅

---

🎀 SYNOPSIS 🎀

int find_next_res (struct resource *parent , resource_size_t start ,
resource_size_t end , unsigned long flags , unsigned long desc , struct
resource *res );

---

🌸 ARGUMENTS 🌸

• parent — the root of the resource tree you're snooping around in 🌳
• start — start address of the resource you're searching for
• end — end address of that exact same resource
• flags — the flags the resource must have (non-negotiable, sorry 😌)
• desc — the descriptor the resource must have
• res — return ptr, if a resource gets found 👑

---

🦋 DESCRIPTION 🦋

so here's the tea, bestie 🍓 — if a resource is found, it returns 0 and *res gets overwritten with the part of the resource that's within [start..end]. if none is found? returns -ENODEV. and if your parameters are invalid? -EINVAL, no cap.

the caller must specify start, end, flags, and desc — and yes, desc may be IORES_DESC_NONE, so don't stress about that one 💖

---

🌈 SEE ALSO 🌈

kernel file ./kernel/resource.c — and like, the whole resource.c friend group:

• request_resource_conflict(9)
• request_resource(9)
• release_resource(9)
• walk_iomem_res_desc(9)
• region_intersects(9)
• find_resource_space(9)
• reallocate_resource(9)
• allocate_resource(9)
• lookup_resource(9)
• insert_resource_conflict(9)
• insert_resource(9)
• insert_resource_expand_to_fit(9)
• remove_resource(9)
• adjust_resource(9)
• resource_alignment(9)
• __request_region(9)
• __release_region(9)
• release_mem_region_adjustable(9)
• merge_system_ram_resource(9)
• devm_request_resource(9)
• devm_release_resource(9)
• devm_request_free_mem_region(9)
• alloc_free_mem_region(9)

---

ngl bestie, read the whole squad before you go poking at parent — the resource tree does not play 😭

---

and that's the whole page, mwah 💋 this one's from ./kernel, October 2026 — catch you in the next manpage, bestie 🧚✨