Merge remote-tracking branch 'remotes/mcayland/tags/qemu-openbios-20220115' into...
[qemu.git] / hw / vfio / ap.c
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/vfio/vfio.h"
18 #include "hw/vfio/vfio-common.h"
19 #include "hw/s390x/ap-device.h"
20 #include "qemu/error-report.h"
21 #include "qemu/module.h"
22 #include "qemu/option.h"
23 #include "qemu/config-file.h"
24 #include "kvm/kvm_s390x.h"
25 #include "migration/vmstate.h"
26 #include "hw/qdev-properties.h"
27 #include "hw/s390x/ap-bridge.h"
28 #include "exec/address-spaces.h"
29 #include "qom/object.h"
30
31 #define TYPE_VFIO_AP_DEVICE "vfio-ap"
32
33 struct VFIOAPDevice {
34 APDevice apdev;
35 VFIODevice vdev;
36 };
37
38 OBJECT_DECLARE_SIMPLE_TYPE(VFIOAPDevice, VFIO_AP_DEVICE)
39
40 static void vfio_ap_compute_needs_reset(VFIODevice *vdev)
41 {
42 vdev->needs_reset = false;
43 }
44
45 /*
46 * We don't need vfio_hot_reset_multi and vfio_eoi operations for
47 * vfio-ap device now.
48 */
49 struct VFIODeviceOps vfio_ap_ops = {
50 .vfio_compute_needs_reset = vfio_ap_compute_needs_reset,
51 };
52
53 static void vfio_ap_put_device(VFIOAPDevice *vapdev)
54 {
55 g_free(vapdev->vdev.name);
56 vfio_put_base_device(&vapdev->vdev);
57 }
58
59 static VFIOGroup *vfio_ap_get_group(VFIOAPDevice *vapdev, Error **errp)
60 {
61 GError *gerror = NULL;
62 char *symlink, *group_path;
63 int groupid;
64
65 symlink = g_strdup_printf("%s/iommu_group", vapdev->vdev.sysfsdev);
66 group_path = g_file_read_link(symlink, &gerror);
67 g_free(symlink);
68
69 if (!group_path) {
70 error_setg(errp, "%s: no iommu_group found for %s: %s",
71 TYPE_VFIO_AP_DEVICE, vapdev->vdev.sysfsdev, gerror->message);
72 g_error_free(gerror);
73 return NULL;
74 }
75
76 if (sscanf(basename(group_path), "%d", &groupid) != 1) {
77 error_setg(errp, "vfio: failed to read %s", group_path);
78 g_free(group_path);
79 return NULL;
80 }
81
82 g_free(group_path);
83
84 return vfio_get_group(groupid, &address_space_memory, errp);
85 }
86
87 static void vfio_ap_realize(DeviceState *dev, Error **errp)
88 {
89 int ret;
90 char *mdevid;
91 VFIOGroup *vfio_group;
92 APDevice *apdev = AP_DEVICE(dev);
93 VFIOAPDevice *vapdev = VFIO_AP_DEVICE(apdev);
94
95 vfio_group = vfio_ap_get_group(vapdev, errp);
96 if (!vfio_group) {
97 return;
98 }
99
100 vapdev->vdev.ops = &vfio_ap_ops;
101 vapdev->vdev.type = VFIO_DEVICE_TYPE_AP;
102 mdevid = basename(vapdev->vdev.sysfsdev);
103 vapdev->vdev.name = g_strdup_printf("%s", mdevid);
104 vapdev->vdev.dev = dev;
105
106 /*
107 * vfio-ap devices operate in a way compatible with discarding of
108 * memory in RAM blocks, as no pages are pinned in the host.
109 * This needs to be set before vfio_get_device() for vfio common to
110 * handle ram_block_discard_disable().
111 */
112 vapdev->vdev.ram_block_discard_allowed = true;
113
114 ret = vfio_get_device(vfio_group, mdevid, &vapdev->vdev, errp);
115 if (ret) {
116 goto out_get_dev_err;
117 }
118
119 return;
120
121 out_get_dev_err:
122 vfio_ap_put_device(vapdev);
123 vfio_put_group(vfio_group);
124 }
125
126 static void vfio_ap_unrealize(DeviceState *dev)
127 {
128 APDevice *apdev = AP_DEVICE(dev);
129 VFIOAPDevice *vapdev = VFIO_AP_DEVICE(apdev);
130 VFIOGroup *group = vapdev->vdev.group;
131
132 vfio_ap_put_device(vapdev);
133 vfio_put_group(group);
134 }
135
136 static Property vfio_ap_properties[] = {
137 DEFINE_PROP_STRING("sysfsdev", VFIOAPDevice, vdev.sysfsdev),
138 DEFINE_PROP_END_OF_LIST(),
139 };
140
141 static void vfio_ap_reset(DeviceState *dev)
142 {
143 int ret;
144 APDevice *apdev = AP_DEVICE(dev);
145 VFIOAPDevice *vapdev = VFIO_AP_DEVICE(apdev);
146
147 ret = ioctl(vapdev->vdev.fd, VFIO_DEVICE_RESET);
148 if (ret) {
149 error_report("%s: failed to reset %s device: %s", __func__,
150 vapdev->vdev.name, strerror(errno));
151 }
152 }
153
154 static const VMStateDescription vfio_ap_vmstate = {
155 .name = "vfio-ap",
156 .unmigratable = 1,
157 };
158
159 static void vfio_ap_class_init(ObjectClass *klass, void *data)
160 {
161 DeviceClass *dc = DEVICE_CLASS(klass);
162
163 device_class_set_props(dc, vfio_ap_properties);
164 dc->vmsd = &vfio_ap_vmstate;
165 dc->desc = "VFIO-based AP device assignment";
166 set_bit(DEVICE_CATEGORY_MISC, dc->categories);
167 dc->realize = vfio_ap_realize;
168 dc->unrealize = vfio_ap_unrealize;
169 dc->hotpluggable = true;
170 dc->reset = vfio_ap_reset;
171 dc->bus_type = TYPE_AP_BUS;
172 }
173
174 static const TypeInfo vfio_ap_info = {
175 .name = TYPE_VFIO_AP_DEVICE,
176 .parent = TYPE_AP_DEVICE,
177 .instance_size = sizeof(VFIOAPDevice),
178 .class_init = vfio_ap_class_init,
179 };
180
181 static void vfio_ap_type_init(void)
182 {
183 type_register_static(&vfio_ap_info);
184 }
185
186 type_init(vfio_ap_type_init)