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
97