summaryrefslogtreecommitdiffstats
path: root/drivers/s390/cio/vfio_ccw_private.h
blob: bbe9babf767b8abd48920799b5b5053b0ab9af8a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
/* SPDX-License-Identifier: GPL-2.0 */
/*
 * Private stuff for vfio_ccw driver
 *
 * Copyright IBM Corp. 2017
 * Copyright Red Hat, Inc. 2019
 *
 * Author(s): Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
 *            Xiao Feng Ren <renxiaof@linux.vnet.ibm.com>
 *            Cornelia Huck <cohuck@redhat.com>
 */

#ifndef _VFIO_CCW_PRIVATE_H_
#define _VFIO_CCW_PRIVATE_H_

#include <linux/completion.h>
#include <linux/eventfd.h>
#include <linux/workqueue.h>
#include <linux/vfio_ccw.h>
#include <asm/debug.h>

#include "css.h"
#include "vfio_ccw_cp.h"

#define VFIO_CCW_OFFSET_SHIFT   10
#define VFIO_CCW_OFFSET_TO_INDEX(off)	(off >> VFIO_CCW_OFFSET_SHIFT)
#define VFIO_CCW_INDEX_TO_OFFSET(index)	((u64)(index) << VFIO_CCW_OFFSET_SHIFT)
#define VFIO_CCW_OFFSET_MASK	(((u64)(1) << VFIO_CCW_OFFSET_SHIFT) - 1)

/* capability chain handling similar to vfio-pci */
struct vfio_ccw_private;
struct vfio_ccw_region;

struct vfio_ccw_regops {
	ssize_t	(*read)(struct vfio_ccw_private *private, char __user *buf,
			size_t count, loff_t *ppos);
	ssize_t	(*write)(struct vfio_ccw_private *private,
			 const char __user *buf, size_t count, loff_t *ppos);
	void	(*release)(struct vfio_ccw_private *private,
			   struct vfio_ccw_region *region);
};

struct vfio_ccw_region {
	u32				type;
	u32				subtype;
	const struct vfio_ccw_regops	*ops;
	void				*data;
	size_t				size;
	u32				flags;
};

int vfio_ccw_register_dev_region(struct vfio_ccw_private *private,
				 unsigned int subtype,
				 const struct vfio_ccw_regops *ops,
				 size_t size, u32 flags, void *data);

int vfio_ccw_register_async_dev_regions(struct vfio_ccw_private *private);

/**
 * struct vfio_ccw_private
 * @sch: pointer to the subchannel
 * @state: internal state of the device
 * @completion: synchronization helper of the I/O completion
 * @avail: available for creating a mediated device
 * @mdev: pointer to the mediated device
 * @nb: notifier for vfio events
 * @io_region: MMIO region to input/output I/O arguments/results
 * @io_mutex: protect against concurrent update of I/O regions
 * @region: additional regions for other subchannel operations
 * @cmd_region: MMIO region for asynchronous I/O commands other than START
 * @num_regions: number of additional regions
 * @cp: channel program for the current I/O operation
 * @irb: irb info received from interrupt
 * @scsw: scsw info
 * @io_trigger: eventfd ctx for signaling userspace I/O results
 * @io_work: work for deferral process of I/O handling
 */
struct vfio_ccw_private {
	struct subchannel	*sch;
	int			state;
	struct completion	*completion;
	atomic_t		avail;
	struct mdev_device	*mdev;
	struct notifier_block	nb;
	struct ccw_io_region	*io_region;
	struct mutex		io_mutex;
	struct vfio_ccw_region *region;
	struct ccw_cmd_region	*cmd_region;
	int num_regions;

	struct channel_program	cp;
	struct irb		irb;
	union scsw		scsw;

	struct eventfd_ctx	*io_trigger;
	struct work_struct	io_work;
} __aligned(8);

extern int vfio_ccw_mdev_reg(struct subchannel *sch);
extern void vfio_ccw_mdev_unreg(struct subchannel *sch);

extern int vfio_ccw_sch_quiesce(struct subchannel *sch);

/*
 * States of the device statemachine.
 */
enum vfio_ccw_state {
	VFIO_CCW_STATE_NOT_OPER,
	VFIO_CCW_STATE_STANDBY,
	VFIO_CCW_STATE_IDLE,
	VFIO_CCW_STATE_CP_PROCESSING,
	VFIO_CCW_STATE_CP_PENDING,
	/* last element! */
	NR_VFIO_CCW_STATES
};

/*
 * Asynchronous events of the device statemachine.
 */
enum vfio_ccw_event {
	VFIO_CCW_EVENT_NOT_OPER,
	VFIO_CCW_EVENT_IO_REQ,
	VFIO_CCW_EVENT_INTERRUPT,
	VFIO_CCW_EVENT_ASYNC_REQ,
	/* last element! */
	NR_VFIO_CCW_EVENTS
};

/*
 * Action called through jumptable.
 */
typedef void (fsm_func_t)(struct vfio_ccw_private *, enum vfio_ccw_event);
extern fsm_func_t *vfio_ccw_jumptable[NR_VFIO_CCW_STATES][NR_VFIO_CCW_EVENTS];

static inline void vfio_ccw_fsm_event(struct vfio_ccw_private *private,
				     int event)
{
	vfio_ccw_jumptable[private->state][event](private, event);
}

extern struct workqueue_struct *vfio_ccw_work_q;


/* s390 debug feature, similar to base cio */
extern debug_info_t *vfio_ccw_debug_msg_id;
extern debug_info_t *vfio_ccw_debug_trace_id;

#define VFIO_CCW_TRACE_EVENT(imp, txt) \
		debug_text_event(vfio_ccw_debug_trace_id, imp, txt)

#define VFIO_CCW_MSG_EVENT(imp, args...) \
		debug_sprintf_event(vfio_ccw_debug_msg_id, imp, ##args)

static inline void VFIO_CCW_HEX_EVENT(int level, void *data, int length)
{
	debug_event(vfio_ccw_debug_trace_id, level, data, length);
}

#endif
OpenPOWER on IntegriCloud