STRUCT VFIO_CCW_PRIVATE(9)

✨ struct vfio_ccw_private(9) ✨

okay so this is a page from the Kernel API Manual bestie, and it's literally just the whole private struct for vfio_ccw laid out for you 💅

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🌸 NAME 🌸

struct vfio_ccw_private —

no cap, the original NAME line has no description after the dash, so we're not inventing one. the vibes are mysterious. the struct is not. 🫶

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🎀 SYNOPSIS 🎀

here's the whole thing, character for character, don't @ me:

struct vfio_ccw_private {
    struct vfio_device vdev;
    int state;
    struct completion       *completion;
    struct ccw_io_region    *io_region;
    struct mutex            io_mutex;
    struct vfio_ccw_region *region;
    struct ccw_cmd_region   *cmd_region;
    struct ccw_schib_region *schib_region;
    struct ccw_crw_region   *crw_region;
    int num_regions;
    struct channel_program  cp;
    struct irb              irb;
    union scsw              scsw;
    spinlock_t crw_lock;
    struct list_head        crw;
    struct eventfd_ctx      *io_trigger;
    struct eventfd_ctx      *crw_trigger;
    struct eventfd_ctx      *req_trigger;
    struct work_struct      io_work;
    struct work_struct      crw_work;
    struct work_struct      notoper_work;
 };

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🦋 Members 🦋

okay this is the main character section, every single field, no skips, let's go 🔥

• vdev — the embedded VFIO device, it's living inside the struct rent-free 🏠
• state — the internal state of the device
• completion — the synchronization helper for I/O completion, it's giving "let me know when you're done" energy
• io_region — the MMIO region where input/output I/O arguments and results go
• io_mutex — protects against concurrent update of I/O resources and the cp lifecycle, so nobody's editing at the same time 🙈
• region — additional regions for the other subchannel operations
• cmd_region — MMIO region for asynchronous I/O commands other than START
• schib_region — MMIO region for SCHIB information
• crw_region — MMIO region for getting channel report words
• num_regions — the number of additional regions
• cp — the channel program for the current I/O operation
• irb — irb info received from interrupt
• scsw — scsw info
• crw_lock — serialization of CRW list information, one at a time pls ✋
• crw — the list of Channel Report Word elements
• io_trigger — eventfd ctx for signaling userspace I/O results
• crw_trigger — eventfd ctx for signaling userspace CRW information
• req_trigger — eventfd ctx for signaling userspace to return device
• io_work — work for the deferral process of I/O handling
• crw_work — work for the deferral process of CRW handling
• notoper_work — work for deferred processing in not-operational state

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🌈 SEE ALSO 🌈

• Kernel file ./drivers/s390/cio/vfio_ccw_private.h struct vfio_ccw_parent(9)

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lowkey important: the SEE ALSO above is exactly what the page says, go read vfio_ccw_parent(9) too bestie, iykyk ⭐

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and that's the whole page, periodt 💖 this lil piece of the Kernel API Manual came from ./drivers/s390/cio, dated October 2026, and yes the version tag is literally just struct vfio_ccw_private(9) again because the manpage said so 😭 slay 🎀