1/*
2 * VFIO based AP matrix device assignment
3 *
4 * Copyright 2018 IBM Corp.
5 * Author(s): Tony Krowiak <akrowiak@linux.ibm.com>
6 * Halil Pasic <pasic@linux.ibm.com>
7 *
8 * This work is licensed under the terms of the GNU GPL, version 2 or (at
9 * your option) any later version. See the COPYING file in the top-level
10 * directory.
11 */
12
13#include "qemu/osdep.h"
14#include <linux/vfio.h>
15#include <sys/ioctl.h>
16#include "qapi/error.h"
17#include "hw/sysbus.h"
18#include "hw/vfio/vfio.h"
19#include "hw/vfio/vfio-common.h"
20#include "hw/s390x/ap-device.h"
21#include "qemu/error-report.h"
22#include "qemu/module.h"
23#include "qemu/option.h"
24#include "qemu/config-file.h"
25#include "cpu.h"
26#include "kvm_s390x.h"
27#include "migration/vmstate.h"
28#include "hw/qdev-properties.h"
29#include "hw/s390x/ap-bridge.h"
30#include "exec/address-spaces.h"
31
32#define VFIO_AP_DEVICE_TYPE "vfio-ap"
33
34typedef struct VFIOAPDevice {
35 APDevice apdev;
36 VFIODevice vdev;
37} VFIOAPDevice;
38
39#define VFIO_AP_DEVICE(obj) \
40 OBJECT_CHECK(VFIOAPDevice, (obj), VFIO_AP_DEVICE_TYPE)
41
42static void vfio_ap_compute_needs_reset(VFIODevice *vdev)
43{
44 vdev->needs_reset = false;
45}
46
47/*
48 * We don't need vfio_hot_reset_multi and vfio_eoi operations for
49 * vfio-ap device now.
50 */
51struct VFIODeviceOps vfio_ap_ops = {
52 .vfio_compute_needs_reset = vfio_ap_compute_needs_reset,
53};
54
55static void vfio_ap_put_device(VFIOAPDevice *vapdev)
56{
57 g_free(vapdev->vdev.name);
58 vfio_put_base_device(&vapdev->vdev);
59}
60
61static VFIOGroup *vfio_ap_get_group(VFIOAPDevice *vapdev, Error **errp)
62{
63 GError *gerror = NULL;
64 char *symlink, *group_path;
65 int groupid;
66
67 symlink = g_strdup_printf("%s/iommu_group", vapdev->vdev.sysfsdev);
68 group_path = g_file_read_link(symlink, &gerror);
69 g_free(symlink);
70
71 if (!group_path) {
72 error_setg(errp, "%s: no iommu_group found for %s: %s",
73 VFIO_AP_DEVICE_TYPE, vapdev->vdev.sysfsdev, gerror->message);
74 return NULL;
75 }
76
77 if (sscanf(basename(group_path), "%d", &groupid) != 1) {
78 error_setg(errp, "vfio: failed to read %s", group_path);
79 g_free(group_path);
80 return NULL;
81 }
82
83 g_free(group_path);
84
85 return vfio_get_group(groupid, &address_space_memory, errp);
86}
87
88static void vfio_ap_realize(DeviceState *dev, Error **errp)
89{
90 int ret;
91 char *mdevid;
92 Error *local_err = NULL;
93 VFIOGroup *vfio_group;
94 APDevice *apdev = AP_DEVICE(dev);
95 VFIOAPDevice *vapdev = VFIO_AP_DEVICE(apdev);
96
97 vfio_group = vfio_ap_get_group(vapdev, &local_err);
98 if (!vfio_group) {
99 goto out_err;
100 }
101
102 vapdev->vdev.ops = &vfio_ap_ops;
103 vapdev->vdev.type = VFIO_DEVICE_TYPE_AP;
104 mdevid = basename(vapdev->vdev.sysfsdev);
105 vapdev->vdev.name = g_strdup_printf("%s", mdevid);
106 vapdev->vdev.dev = dev;
107
108 /*
109 * vfio-ap devices operate in a way compatible with
110 * memory ballooning, as no pages are pinned in the host.
111 * This needs to be set before vfio_get_device() for vfio common to
112 * handle the balloon inhibitor.
113 */
114 vapdev->vdev.balloon_allowed = true;
115
116 ret = vfio_get_device(vfio_group, mdevid, &vapdev->vdev, &local_err);
117 if (ret) {
118 goto out_get_dev_err;
119 }
120
121 return;
122
123out_get_dev_err:
124 vfio_ap_put_device(vapdev);
125 vfio_put_group(vfio_group);
126out_err:
127 error_propagate(errp, local_err);
128}
129
130static void vfio_ap_unrealize(DeviceState *dev, Error **errp)
131{
132 APDevice *apdev = AP_DEVICE(dev);
133 VFIOAPDevice *vapdev = VFIO_AP_DEVICE(apdev);
134 VFIOGroup *group = vapdev->vdev.group;
135
136 vfio_ap_put_device(vapdev);
137 vfio_put_group(group);
138}
139
140static Property vfio_ap_properties[] = {
141 DEFINE_PROP_STRING("sysfsdev", VFIOAPDevice, vdev.sysfsdev),
142 DEFINE_PROP_END_OF_LIST(),
143};
144
145static void vfio_ap_reset(DeviceState *dev)
146{
147 int ret;
148 APDevice *apdev = AP_DEVICE(dev);
149 VFIOAPDevice *vapdev = VFIO_AP_DEVICE(apdev);
150
151 ret = ioctl(vapdev->vdev.fd, VFIO_DEVICE_RESET);
152 if (ret) {
153 error_report("%s: failed to reset %s device: %s", __func__,
154 vapdev->vdev.name, strerror(errno));
155 }
156}
157
158static const VMStateDescription vfio_ap_vmstate = {
159 .name = "vfio-ap",
160 .unmigratable = 1,
161};
162
163static void vfio_ap_class_init(ObjectClass *klass, void *data)
164{
165 DeviceClass *dc = DEVICE_CLASS(klass);
166
167 dc->props = vfio_ap_properties;
168 dc->vmsd = &vfio_ap_vmstate;
169 dc->desc = "VFIO-based AP device assignment";
170 set_bit(DEVICE_CATEGORY_MISC, dc->categories);
171 dc->realize = vfio_ap_realize;
172 dc->unrealize = vfio_ap_unrealize;
173 dc->hotpluggable = true;
174 dc->reset = vfio_ap_reset;
175 dc->bus_type = TYPE_AP_BUS;
176}
177
178static const TypeInfo vfio_ap_info = {
179 .name = VFIO_AP_DEVICE_TYPE,
180 .parent = AP_DEVICE_TYPE,
181 .instance_size = sizeof(VFIOAPDevice),
182 .class_init = vfio_ap_class_init,
183};
184
185static void vfio_ap_type_init(void)
186{
187 type_register_static(&vfio_ap_info);
188}
189
190type_init(vfio_ap_type_init)
191