drivers/s390/cio/vfio_ccw_private.h

   1 /*
   2  * Private stuff for vfio_ccw driver
   3  *
   4  * Copyright IBM Corp. 2017
   5  *
   6  * Author(s): Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
   7  *            Xiao Feng Ren <renxiaof@linux.vnet.ibm.com>
   8  */
   9
  10 #ifndef _VFIO_CCW_PRIVATE_H_
  11 #define _VFIO_CCW_PRIVATE_H_
  12
  13 #include <linux/completion.h>
  14 #include <linux/eventfd.h>
  15 #include <linux/workqueue.h>
  16 #include <linux/vfio_ccw.h>
  17
  18 #include "css.h"
  19 #include "vfio_ccw_cp.h"
  20
  21 /**
  22  * struct vfio_ccw_private
  23  * @sch: pointer to the subchannel
  24  * @state: internal state of the device
  25  * @completion: synchronization helper of the I/O completion
  26  * @avail: available for creating a mediated device
  27  * @mdev: pointer to the mediated device
  28  * @nb: notifier for vfio events
  29  * @io_region: MMIO region to input/output I/O arguments/results
  30  * @cp: channel program for the current I/O operation
  31  * @irb: irb info received from interrupt
  32  * @scsw: scsw info
  33  * @io_trigger: eventfd ctx for signaling userspace I/O results
  34  * @io_work: work for deferral process of I/O handling
  35  */
  36 struct vfio_ccw_private {
  37         struct subchannel       *sch;
  38         int                     state;
  39         struct completion       *completion;
  40         atomic_t                avail;
  41         struct mdev_device      *mdev;
  42         struct notifier_block   nb;
  43         struct ccw_io_region    io_region;
  44
  45         struct channel_program  cp;
  46         struct irb              irb;
  47         union scsw              scsw;
  48
  49         struct eventfd_ctx      *io_trigger;
  50         struct work_struct      io_work;
  51 } __aligned(8);
  52
  53 extern int vfio_ccw_mdev_reg(struct subchannel *sch);
  54 extern void vfio_ccw_mdev_unreg(struct subchannel *sch);
  55
  56 extern int vfio_ccw_sch_quiesce(struct subchannel *sch);
  57
  58 /*
  59  * States of the device statemachine.
  60  */
  61 enum vfio_ccw_state {
  62         VFIO_CCW_STATE_NOT_OPER,
  63         VFIO_CCW_STATE_STANDBY,
  64         VFIO_CCW_STATE_IDLE,
  65         VFIO_CCW_STATE_BOXED,
  66         VFIO_CCW_STATE_BUSY,
  67         /* last element! */
  68         NR_VFIO_CCW_STATES
  69 };
  70
  71 /*
  72  * Asynchronous events of the device statemachine.
  73  */
  74 enum vfio_ccw_event {
  75         VFIO_CCW_EVENT_NOT_OPER,
  76         VFIO_CCW_EVENT_IO_REQ,
  77         VFIO_CCW_EVENT_INTERRUPT,
  78         /* last element! */
  79         NR_VFIO_CCW_EVENTS
  80 };
  81
  82 /*
  83  * Action called through jumptable.
  84  */
  85 typedef void (fsm_func_t)(struct vfio_ccw_private *, enum vfio_ccw_event);
  86 extern fsm_func_t *vfio_ccw_jumptable[NR_VFIO_CCW_STATES][NR_VFIO_CCW_EVENTS];
  87
  88 static inline void vfio_ccw_fsm_event(struct vfio_ccw_private *private,
  89                                      int event)
  90 {
  91         vfio_ccw_jumptable[private->state][event](private, event);
  92 }
  93
  94 extern struct workqueue_struct *vfio_ccw_work_q;
  95
  96 #endif