pci_rebar_get_max_size(9)

🦋 pci_rebar_get_max_size(9) 🦋

okay bestie, this is a page from the Kernel API Manual — and yes, we are about to find out the biggest supported size of a resizable BAR. iconic behavior only 💅

✨ NAME ✨

pci_rebar_get_max_size — get the maximum supported size of a BAR 🎀

🎀 SYNOPSIS 🎀

int pci_rebar_get_max_size (struct pci_dev *pdev , int bar );

💅 ARGUMENTS 💅

• pdev — the PCI device 💳
• bar — the BAR to query 🎯

🌸 DESCRIPTION 🌸

Get the largest supported size of a resizable BAR as a size. That's it, that's the vibe — it's giving "maximum supported size" realness ✨

🔥 RETURN 🔥

It returns the encoded maximum BAR size as defined in the PCIe spec — 0=1MB, 31=128TB — or -NOENT on error. No cap, those are the exact numbers 🫶

real talk: this is the encoded value, so don't treat it like a raw byte count without checking the encoding, iykyk.

🫶 SEE ALSO 🫶

Kernel file ./drivers/pci/rebar.c plus the whole friend group:

• pci_rebar_bytes_to_size(9)
• pci_rebar_size_to_bytes(9)
• pci_rebar_find_pos(9)
• pci_rebar_get_possible_sizes(9)
• pci_rebar_size_supported(9)
• pci_rebar_get_current_size(9)
• pci_rebar_set_size(9)
• pci_resize_resource(9)

mwah 💋 this cutie came from ./drivers/pci, dated October 2026. bestie signing off 🎀