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
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
|
/*
* Physical device callbacks for vfio_ccw
*
* Copyright IBM Corp. 2017
*
* Author(s): Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
* Xiao Feng Ren <renxiaof@linux.vnet.ibm.com>
*/
#include <linux/vfio.h>
#include <linux/mdev.h>
#include "vfio_ccw_private.h"
static int vfio_ccw_mdev_notifier(struct notifier_block *nb,
unsigned long action,
void *data)
{
struct vfio_ccw_private *private =
container_of(nb, struct vfio_ccw_private, nb);
if (!private)
return NOTIFY_STOP;
/*
* TODO:
* Vendor drivers MUST unpin pages in response to an
* invalidation.
*/
if (action == VFIO_IOMMU_NOTIFY_DMA_UNMAP)
return NOTIFY_BAD;
return NOTIFY_DONE;
}
static ssize_t name_show(struct kobject *kobj, struct device *dev, char *buf)
{
return sprintf(buf, "I/O subchannel (Non-QDIO)\n");
}
MDEV_TYPE_ATTR_RO(name);
static ssize_t device_api_show(struct kobject *kobj, struct device *dev,
char *buf)
{
return sprintf(buf, "%s\n", VFIO_DEVICE_API_CCW_STRING);
}
MDEV_TYPE_ATTR_RO(device_api);
static ssize_t available_instances_show(struct kobject *kobj,
struct device *dev, char *buf)
{
struct vfio_ccw_private *private = dev_get_drvdata(dev);
return sprintf(buf, "%d\n", atomic_read(&private->avail));
}
MDEV_TYPE_ATTR_RO(available_instances);
static struct attribute *mdev_types_attrs[] = {
&mdev_type_attr_name.attr,
&mdev_type_attr_device_api.attr,
&mdev_type_attr_available_instances.attr,
NULL,
};
static struct attribute_group mdev_type_group = {
.name = "io",
.attrs = mdev_types_attrs,
};
struct attribute_group *mdev_type_groups[] = {
&mdev_type_group,
NULL,
};
static int vfio_ccw_mdev_create(struct kobject *kobj, struct mdev_device *mdev)
{
struct vfio_ccw_private *private =
dev_get_drvdata(mdev_parent_dev(mdev));
if (atomic_dec_if_positive(&private->avail) < 0)
return -EPERM;
private->mdev = mdev;
return 0;
}
static int vfio_ccw_mdev_remove(struct mdev_device *mdev)
{
struct vfio_ccw_private *private;
struct subchannel *sch;
int ret;
private = dev_get_drvdata(mdev_parent_dev(mdev));
sch = private->sch;
ret = vfio_ccw_sch_quiesce(sch);
if (ret)
return ret;
ret = cio_enable_subchannel(sch, (u32)(unsigned long)sch);
if (ret)
return ret;
private->mdev = NULL;
atomic_inc(&private->avail);
return 0;
}
static int vfio_ccw_mdev_open(struct mdev_device *mdev)
{
struct vfio_ccw_private *private =
dev_get_drvdata(mdev_parent_dev(mdev));
unsigned long events = VFIO_IOMMU_NOTIFY_DMA_UNMAP;
private->nb.notifier_call = vfio_ccw_mdev_notifier;
return vfio_register_notifier(mdev_dev(mdev), VFIO_IOMMU_NOTIFY,
&events, &private->nb);
}
void vfio_ccw_mdev_release(struct mdev_device *mdev)
{
struct vfio_ccw_private *private =
dev_get_drvdata(mdev_parent_dev(mdev));
vfio_unregister_notifier(mdev_dev(mdev), VFIO_IOMMU_NOTIFY,
&private->nb);
}
static ssize_t vfio_ccw_mdev_read(struct mdev_device *mdev,
char __user *buf,
size_t count,
loff_t *ppos)
{
struct vfio_ccw_private *private;
struct ccw_io_region *region;
if (*ppos + count > sizeof(*region))
return -EINVAL;
private = dev_get_drvdata(mdev_parent_dev(mdev));
if (!private)
return -ENODEV;
region = &private->io_region;
if (copy_to_user(buf, (void *)region + *ppos, count))
return -EFAULT;
return count;
}
static ssize_t vfio_ccw_mdev_write(struct mdev_device *mdev,
const char __user *buf,
size_t count,
loff_t *ppos)
{
struct vfio_ccw_private *private;
struct ccw_io_region *region;
if (*ppos + count > sizeof(*region))
return -EINVAL;
private = dev_get_drvdata(mdev_parent_dev(mdev));
if (!private)
return -ENODEV;
region = &private->io_region;
if (copy_from_user((void *)region + *ppos, buf, count))
return -EFAULT;
region->ret_code = 0;
return count;
}
static const struct mdev_parent_ops vfio_ccw_mdev_ops = {
.owner = THIS_MODULE,
.supported_type_groups = mdev_type_groups,
.create = vfio_ccw_mdev_create,
.remove = vfio_ccw_mdev_remove,
.open = vfio_ccw_mdev_open,
.release = vfio_ccw_mdev_release,
.read = vfio_ccw_mdev_read,
.write = vfio_ccw_mdev_write,
};
int vfio_ccw_mdev_reg(struct subchannel *sch)
{
return mdev_register_device(&sch->dev, &vfio_ccw_mdev_ops);
}
void vfio_ccw_mdev_unreg(struct subchannel *sch)
{
mdev_unregister_device(&sch->dev);
}
|
