pci_request_region(9)

📦 version 7.3.1, in nixpkgs unstable

💅 pci_request_region ✨

okay so this is a page from the Kernel API Manual and honestly? it's a whole vibe. it's about calling dibs on PCI hardware, and yes, you need to understand it, bestie 🫶

🌸 NAME 🌸

pci_request_region — reserve PCI I/O and memory resource 🎀

⭐ SYNOPSIS ⭐

int pci_request_region (struct pci_dev *pdev , int bar , const char
*name );

like, that's the whole call. three things in, one int out. slay 💅

🦋 ARGUMENTS 🦋

  • pdev — the PCI device whose resources you're reserving. main character energy, honestly 🔥
  • bar — which BAR you wanna reserve. yes, just the BAR. pick one 👑
  • name — the name of the driver that's asking for the resource. it's you. you're the owner now 🙈

💖 RETURN 💖

0 on success, negative error code on failure. that's it, that's the deal ⭐

✨ DESCRIPTION ✨

okay so here's what's happening: this marks the PCI region that belongs to PCI device pdev, BAR bar, as being reserved by whoever name says. like putting a little sticky note on it that says "mine, do not touch" 🎀

⚠️ and this is the important part, bestie, do not skip it: do not access any address inside the PCI regions unless this call returns successfully. no cap. if it didn't come back clean, hands off 💀

it returns 0 on success, or EBUSY on error. and it also prints a warning message when it fails, so you'll know 😭

🌈 SEE ALSO 🌈

kernel file ./drivers/pci/pci.c 🧚 and literally the entire extended pci cinematic universe:

and that's the whole page, bestie 💜

this one lives in ./drivers/pci and it's dated October 2026 — so yeah, future-coded, iconic, iykyk 🎀✨💖

📦 where this page comes from