aboutsummaryrefslogtreecommitdiff
path: root/hw/vfio/ap.c
blob: 4b32aca1a05e8fbac40ca966bed21436cbe38d28 (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
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
/*
 * VFIO based AP matrix device assignment
 *
 * Copyright 2018 IBM Corp.
 * Author(s): Tony Krowiak <akrowiak@linux.ibm.com>
 *            Halil Pasic <pasic@linux.ibm.com>
 *
 * This work is licensed under the terms of the GNU GPL, version 2 or (at
 * your option) any later version. See the COPYING file in the top-level
 * directory.
 */

#include "qemu/osdep.h"
#include <linux/vfio.h>
#include <sys/ioctl.h>
#include "qapi/error.h"
#include "hw/vfio/vfio.h"
#include "hw/vfio/vfio-common.h"
#include "hw/s390x/ap-device.h"
#include "qemu/error-report.h"
#include "qemu/module.h"
#include "qemu/option.h"
#include "qemu/config-file.h"
#include "kvm_s390x.h"
#include "migration/vmstate.h"
#include "hw/qdev-properties.h"
#include "hw/s390x/ap-bridge.h"
#include "exec/address-spaces.h"
#include "qom/object.h"

#define TYPE_VFIO_AP_DEVICE      "vfio-ap"

struct VFIOAPDevice {
    APDevice apdev;
    VFIODevice vdev;
};

OBJECT_DECLARE_SIMPLE_TYPE(VFIOAPDevice, VFIO_AP_DEVICE)

static void vfio_ap_compute_needs_reset(VFIODevice *vdev)
{
    vdev->needs_reset = false;
}

/*
 * We don't need vfio_hot_reset_multi and vfio_eoi operations for
 * vfio-ap device now.
 */
struct VFIODeviceOps vfio_ap_ops = {
    .vfio_compute_needs_reset = vfio_ap_compute_needs_reset,
};

static void vfio_ap_put_device(VFIOAPDevice *vapdev)
{
    g_free(vapdev->vdev.name);
    vfio_put_base_device(&vapdev->vdev);
}

static VFIOGroup *vfio_ap_get_group(VFIOAPDevice *vapdev, Error **errp)
{
    GError *gerror = NULL;
    char *symlink, *group_path;
    int groupid;

    symlink = g_strdup_printf("%s/iommu_group", vapdev->vdev.sysfsdev);
    group_path = g_file_read_link(symlink, &gerror);
    g_free(symlink);

    if (!group_path) {
        error_setg(errp, "%s: no iommu_group found for %s: %s",
                   TYPE_VFIO_AP_DEVICE, vapdev->vdev.sysfsdev, gerror->message);
        g_error_free(gerror);
        return NULL;
    }

    if (sscanf(basename(group_path), "%d", &groupid) != 1) {
        error_setg(errp, "vfio: failed to read %s", group_path);
        g_free(group_path);
        return NULL;
    }

    g_free(group_path);

    return vfio_get_group(groupid, &address_space_memory, errp);
}

static void vfio_ap_realize(DeviceState *dev, Error **errp)
{
    int ret;
    char *mdevid;
    VFIOGroup *vfio_group;
    APDevice *apdev = AP_DEVICE(dev);
    VFIOAPDevice *vapdev = VFIO_AP_DEVICE(apdev);

    vfio_group = vfio_ap_get_group(vapdev, errp);
    if (!vfio_group) {
        return;
    }

    vapdev->vdev.ops = &vfio_ap_ops;
    vapdev->vdev.type = VFIO_DEVICE_TYPE_AP;
    mdevid = basename(vapdev->vdev.sysfsdev);
    vapdev->vdev.name = g_strdup_printf("%s", mdevid);
    vapdev->vdev.dev = dev;

    /*
     * vfio-ap devices operate in a way compatible with discarding of
     * memory in RAM blocks, as no pages are pinned in the host.
     * This needs to be set before vfio_get_device() for vfio common to
     * handle ram_block_discard_disable().
     */
    vapdev->vdev.ram_block_discard_allowed = true;

    ret = vfio_get_device(vfio_group, mdevid, &vapdev->vdev, errp);
    if (ret) {
        goto out_get_dev_err;
    }

    return;

out_get_dev_err:
    vfio_ap_put_device(vapdev);
    vfio_put_group(vfio_group);
}

static void vfio_ap_unrealize(DeviceState *dev)
{
    APDevice *apdev = AP_DEVICE(dev);
    VFIOAPDevice *vapdev = VFIO_AP_DEVICE(apdev);
    VFIOGroup *group = vapdev->vdev.group;

    vfio_ap_put_device(vapdev);
    vfio_put_group(group);
}

static Property vfio_ap_properties[] = {
    DEFINE_PROP_STRING("sysfsdev", VFIOAPDevice, vdev.sysfsdev),
    DEFINE_PROP_END_OF_LIST(),
};

static void vfio_ap_reset(DeviceState *dev)
{
    int ret;
    APDevice *apdev = AP_DEVICE(dev);
    VFIOAPDevice *vapdev = VFIO_AP_DEVICE(apdev);

    ret = ioctl(vapdev->vdev.fd, VFIO_DEVICE_RESET);
    if (ret) {
        error_report("%s: failed to reset %s device: %s", __func__,
                     vapdev->vdev.name, strerror(errno));
    }
}

static const VMStateDescription vfio_ap_vmstate = {
    .name = "vfio-ap",
    .unmigratable = 1,
};

static void vfio_ap_class_init(ObjectClass *klass, void *data)
{
    DeviceClass *dc = DEVICE_CLASS(klass);

    device_class_set_props(dc, vfio_ap_properties);
    dc->vmsd = &vfio_ap_vmstate;
    dc->desc = "VFIO-based AP device assignment";
    set_bit(DEVICE_CATEGORY_MISC, dc->categories);
    dc->realize = vfio_ap_realize;
    dc->unrealize = vfio_ap_unrealize;
    dc->hotpluggable = true;
    dc->reset = vfio_ap_reset;
    dc->bus_type = TYPE_AP_BUS;
}

static const TypeInfo vfio_ap_info = {
    .name = TYPE_VFIO_AP_DEVICE,
    .parent = TYPE_AP_DEVICE,
    .instance_size = sizeof(VFIOAPDevice),
    .class_init = vfio_ap_class_init,
};

static void vfio_ap_type_init(void)
{
    type_register_static(&vfio_ap_info);
}

type_init(vfio_ap_type_init)