drivers/s390/cio/vfio_ccw_private.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /*
   3  * Private stuff for vfio_ccw driver
   4  *
   5  * Copyright IBM Corp. 2017
   6  *
   7  * Author(s): Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
   8  *            Xiao Feng Ren <renxiaof@linux.vnet.ibm.com>
   9  */
  10
  11 #ifndef _VFIO_CCW_PRIVATE_H_
  12 #define _VFIO_CCW_PRIVATE_H_
  13
  14 #include <linux/completion.h>
  15 #include <linux/eventfd.h>
  16 #include <linux/workqueue.h>
  17 #include <linux/vfio_ccw.h>
  18
  19 #include "css.h"
  20 #include "vfio_ccw_cp.h"
  21
  22 /**
  23  * struct vfio_ccw_private
  24  * @sch: pointer to the subchannel
  25  * @state: internal state of the device
  26  * @completion: synchronization helper of the I/O completion
  27  * @avail: available for creating a mediated device
  28  * @mdev: pointer to the mediated device
  29  * @nb: notifier for vfio events
  30  * @io_region: MMIO region to input/output I/O arguments/results
  31  * @cp: channel program for the current I/O operation
  32  * @irb: irb info received from interrupt
  33  * @scsw: scsw info
  34  * @io_trigger: eventfd ctx for signaling userspace I/O results
  35  * @io_work: work for deferral process of I/O handling
  36  */
  37 struct vfio_ccw_private {
  38         struct subchannel       *sch;
  39         int                     state;
  40         struct completion       *completion;
  41         atomic_t                avail;
  42         struct mdev_device      *mdev;
  43         struct notifier_block   nb;
  44         struct ccw_io_region    io_region;
  45
  46         struct channel_program  cp;
  47         struct irb              irb;
  48         union scsw              scsw;
  49
  50         struct eventfd_ctx      *io_trigger;
  51         struct work_struct      io_work;
  52 } __aligned(8);
  53
  54 extern int vfio_ccw_mdev_reg(struct subchannel *sch);
  55 extern void vfio_ccw_mdev_unreg(struct subchannel *sch);
  56
  57 extern int vfio_ccw_sch_quiesce(struct subchannel *sch);
  58
  59 /*
  60  * States of the device statemachine.
  61  */
  62 enum vfio_ccw_state {
  63         VFIO_CCW_STATE_NOT_OPER,
  64         VFIO_CCW_STATE_STANDBY,
  65         VFIO_CCW_STATE_IDLE,
  66         VFIO_CCW_STATE_BOXED,
  67         VFIO_CCW_STATE_BUSY,
  68         /* last element! */
  69         NR_VFIO_CCW_STATES
  70 };
  71
  72 /*
  73  * Asynchronous events of the device statemachine.
  74  */
  75 enum vfio_ccw_event {
  76         VFIO_CCW_EVENT_NOT_OPER,
  77         VFIO_CCW_EVENT_IO_REQ,
  78         VFIO_CCW_EVENT_INTERRUPT,
  79         /* last element! */
  80         NR_VFIO_CCW_EVENTS
  81 };
  82
  83 /*
  84  * Action called through jumptable.
  85  */
  86 typedef void (fsm_func_t)(struct vfio_ccw_private *, enum vfio_ccw_event);
  87 extern fsm_func_t *vfio_ccw_jumptable[NR_VFIO_CCW_STATES][NR_VFIO_CCW_EVENTS];
  88
  89 static inline void vfio_ccw_fsm_event(struct vfio_ccw_private *private,
  90                                      int event)
  91 {
  92         vfio_ccw_jumptable[private->state][event](private, event);
  93 }
  94
  95 extern struct workqueue_struct *vfio_ccw_work_q;
  96
  97 #endif