STRUCT VIRTIO_PCI_MODERN_DEVICE(9)

🌸 STRUCT VIRTIO_PCI_MODERN_DEVICE(9) 🌸

okay bestie, gather round 💖 so this is a page from the Kernel API Manual — it's the struct virtio_pci_modern_device, and it's literally just the info bucket for modern PCI virtio. that's the whole NAME vibe: lowkey the modern PCI virtio info holder, no cap ✨

✨ SYNOPSIS ✨

here's the whole struct, copied exactly, do not touch a single character or i stg 👑

struct virtio_pci_modern_device {
    struct pci_dev *pci_dev;
    struct virtio_pci_common_cfg __iomem *common;
    void __iomem *device;
    void __iomem *notify_base;
    resource_size_t notify_pa;
    u8 __iomem *isr;
    size_t notify_len;
    size_t device_len;
    size_t common_len;
    int notify_map_cap;
    u32 notify_offset_multiplier;
    int modern_bars;
    struct virtio_device_id id;
    int (*device_id_check)(struct pci_dev *pdev);
    u64 dma_mask;
 };

🎀 Members 🎀

these are the fields, and every single one matters, so let's go one by one like a proper group chat roll call 🫶

• pci_dev — ptr to the PCI device struct 💅
• common — where the common capability lives in the PCI config
• device — device-specific data (non-legacy mode), iconic behavior only 🦋
• notify_base — base of vq notifications (non-legacy mode)
• notify_pa — the physical base of vq notifications
• isr — where to read and clear the interrupt ⭐
• notify_len — so we can sanity-check accesses 👀
• device_len — same deal, so we can sanity-check accesses 👀
• notify_map_cap — capability for when we need to map notifications per-vq
• notify_offset_multiplier — multiply queue_notify_off by this value (non-legacy mode).
• modern_bars — bitmask of BARs
• id — device and vendor id 🏷️
• device_id_check — callback defined before vp_modern_probe, used to verify the PCI device is a vendor's expected device rather than the standard virtio PCI device. returns the found device id or ERRNO 😭
• dma_mask — optional mask instead of the traditional DMA_BIT_MASK(64), for vendor devices with DMA space address limitations 🧚

ngl, that device_id_check one is doing a lot of work in one line, so read it twice bestie — it's the vendor-vs-standard-virtio check, and it hands back either the found device id or ERRNO. fr fr. 💀

🔥 SEE ALSO 🔥

• Kernel file ./include/linux/virtio_pci_modern.h

and that's the whole thing, periodt 💜 this lil' page is served straight from ./include/linux, dated October 2026, and yeah the header up top is abbreviated as struct virt...odern_device(9) because terminals are dramatic like that — anyway ily, go read the actual header, mwah 🍓✨