1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3 * Private stuff for vfio_ccw driver
4 *
5 * Copyright IBM Corp. 2017
6 * Copyright Red Hat, Inc. 2019
7 *
8 * Author(s): Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
9 * Xiao Feng Ren <renxiaof@linux.vnet.ibm.com>
10 * Cornelia Huck <cohuck@redhat.com>
11 */
12
13 #ifndef _VFIO_CCW_PRIVATE_H_
14 #define _VFIO_CCW_PRIVATE_H_
15
16 #include <linux/completion.h>
17 #include <linux/eventfd.h>
18 #include <linux/workqueue.h>
19 #include <linux/vfio_ccw.h>
20 #include <asm/crw.h>
21 #include <asm/debug.h>
22
23 #include "css.h"
24 #include "vfio_ccw_cp.h"
25
26 #define VFIO_CCW_OFFSET_SHIFT 10
27 #define VFIO_CCW_OFFSET_TO_INDEX(off) (off >> VFIO_CCW_OFFSET_SHIFT)
28 #define VFIO_CCW_INDEX_TO_OFFSET(index) ((u64)(index) << VFIO_CCW_OFFSET_SHIFT)
29 #define VFIO_CCW_OFFSET_MASK (((u64)(1) << VFIO_CCW_OFFSET_SHIFT) - 1)
30
31 /* capability chain handling similar to vfio-pci */
32 struct vfio_ccw_private;
33 struct vfio_ccw_region;
34
35 struct vfio_ccw_regops {
36 ssize_t (*read)(struct vfio_ccw_private *private, char __user *buf,
37 size_t count, loff_t *ppos);
38 ssize_t (*write)(struct vfio_ccw_private *private,
39 const char __user *buf, size_t count, loff_t *ppos);
40 void (*release)(struct vfio_ccw_private *private,
41 struct vfio_ccw_region *region);
42 };
43
44 struct vfio_ccw_region {
45 u32 type;
46 u32 subtype;
47 const struct vfio_ccw_regops *ops;
48 void *data;
49 size_t size;
50 u32 flags;
51 };
52
53 int vfio_ccw_register_dev_region(struct vfio_ccw_private *private,
54 unsigned int subtype,
55 const struct vfio_ccw_regops *ops,
56 size_t size, u32 flags, void *data);
57 void vfio_ccw_unregister_dev_regions(struct vfio_ccw_private *private);
58
59 int vfio_ccw_register_async_dev_regions(struct vfio_ccw_private *private);
60 int vfio_ccw_register_schib_dev_regions(struct vfio_ccw_private *private);
61 int vfio_ccw_register_crw_dev_regions(struct vfio_ccw_private *private);
62
63 struct vfio_ccw_crw {
64 struct list_head next;
65 struct crw crw;
66 };
67
68 /**
69 * struct vfio_ccw_private
70 * @sch: pointer to the subchannel
71 * @state: internal state of the device
72 * @completion: synchronization helper of the I/O completion
73 * @avail: available for creating a mediated device
74 * @mdev: pointer to the mediated device
75 * @nb: notifier for vfio events
76 * @io_region: MMIO region to input/output I/O arguments/results
77 * @io_mutex: protect against concurrent update of I/O regions
78 * @region: additional regions for other subchannel operations
79 * @cmd_region: MMIO region for asynchronous I/O commands other than START
80 * @schib_region: MMIO region for SCHIB information
81 * @crw_region: MMIO region for getting channel report words
82 * @num_regions: number of additional regions
83 * @cp: channel program for the current I/O operation
84 * @irb: irb info received from interrupt
85 * @scsw: scsw info
86 * @io_trigger: eventfd ctx for signaling userspace I/O results
87 * @io_work: work for deferral process of I/O handling
88 */
89 struct vfio_ccw_private {
90 struct subchannel *sch;
91 int state;
92 struct completion *completion;
93 atomic_t avail;
94 struct mdev_device *mdev;
95 struct notifier_block nb;
96 struct ccw_io_region *io_region;
97 struct mutex io_mutex;
98 struct vfio_ccw_region *region;
99 struct ccw_cmd_region *cmd_region;
100 struct ccw_schib_region *schib_region;
101 struct ccw_crw_region *crw_region;
102 int num_regions;
103
104 struct channel_program cp;
105 struct irb irb;
106 union scsw scsw;
107 struct list_head crw;
108
109 struct eventfd_ctx *io_trigger;
110 struct eventfd_ctx *crw_trigger;
111 struct work_struct io_work;
112 struct work_struct crw_work;
113 } __aligned(8);
114
115 extern int vfio_ccw_mdev_reg(struct subchannel *sch);
116 extern void vfio_ccw_mdev_unreg(struct subchannel *sch);
117
118 extern int vfio_ccw_sch_quiesce(struct subchannel *sch);
119
120 /*
121 * States of the device statemachine.
122 */
123 enum vfio_ccw_state {
124 VFIO_CCW_STATE_NOT_OPER,
125 VFIO_CCW_STATE_STANDBY,
126 VFIO_CCW_STATE_IDLE,
127 VFIO_CCW_STATE_CP_PROCESSING,
128 VFIO_CCW_STATE_CP_PENDING,
129 /* last element! */
130 NR_VFIO_CCW_STATES
131 };
132
133 /*
134 * Asynchronous events of the device statemachine.
135 */
136 enum vfio_ccw_event {
137 VFIO_CCW_EVENT_NOT_OPER,
138 VFIO_CCW_EVENT_IO_REQ,
139 VFIO_CCW_EVENT_INTERRUPT,
140 VFIO_CCW_EVENT_ASYNC_REQ,
141 /* last element! */
142 NR_VFIO_CCW_EVENTS
143 };
144
145 /*
146 * Action called through jumptable.
147 */
148 typedef void (fsm_func_t)(struct vfio_ccw_private *, enum vfio_ccw_event);
149 extern fsm_func_t *vfio_ccw_jumptable[NR_VFIO_CCW_STATES][NR_VFIO_CCW_EVENTS];
150
vfio_ccw_fsm_event(struct vfio_ccw_private * private,int event)151 static inline void vfio_ccw_fsm_event(struct vfio_ccw_private *private,
152 int event)
153 {
154 trace_vfio_ccw_fsm_event(private->sch->schid, private->state, event);
155 vfio_ccw_jumptable[private->state][event](private, event);
156 }
157
158 extern struct workqueue_struct *vfio_ccw_work_q;
159
160
161 /* s390 debug feature, similar to base cio */
162 extern debug_info_t *vfio_ccw_debug_msg_id;
163 extern debug_info_t *vfio_ccw_debug_trace_id;
164
165 #define VFIO_CCW_TRACE_EVENT(imp, txt) \
166 debug_text_event(vfio_ccw_debug_trace_id, imp, txt)
167
168 #define VFIO_CCW_MSG_EVENT(imp, args...) \
169 debug_sprintf_event(vfio_ccw_debug_msg_id, imp, ##args)
170
VFIO_CCW_HEX_EVENT(int level,void * data,int length)171 static inline void VFIO_CCW_HEX_EVENT(int level, void *data, int length)
172 {
173 debug_event(vfio_ccw_debug_trace_id, level, data, length);
174 }
175
176 #endif
177