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 CONFIG_DEVICES /* CONFIG_IOMMUFD */ 15 #include <linux/vfio.h> 16 #include <sys/ioctl.h> 17 #include "qapi/error.h" 18 #include "hw/vfio/vfio-common.h" 19 #include "sysemu/iommufd.h" 20 #include "hw/s390x/ap-device.h" 21 #include "qemu/error-report.h" 22 #include "qemu/event_notifier.h" 23 #include "qemu/main-loop.h" 24 #include "qemu/module.h" 25 #include "qemu/option.h" 26 #include "qemu/config-file.h" 27 #include "kvm/kvm_s390x.h" 28 #include "migration/vmstate.h" 29 #include "hw/qdev-properties.h" 30 #include "hw/s390x/ap-bridge.h" 31 #include "exec/address-spaces.h" 32 #include "qom/object.h" 33 34 #define TYPE_VFIO_AP_DEVICE "vfio-ap" 35 36 struct VFIOAPDevice { 37 APDevice apdev; 38 VFIODevice vdev; 39 EventNotifier req_notifier; 40 }; 41 42 OBJECT_DECLARE_SIMPLE_TYPE(VFIOAPDevice, VFIO_AP_DEVICE) 43 44 static void vfio_ap_compute_needs_reset(VFIODevice *vdev) 45 { 46 vdev->needs_reset = false; 47 } 48 49 /* 50 * We don't need vfio_hot_reset_multi and vfio_eoi operations for 51 * vfio-ap device now. 52 */ 53 struct VFIODeviceOps vfio_ap_ops = { 54 .vfio_compute_needs_reset = vfio_ap_compute_needs_reset, 55 }; 56 57 static void vfio_ap_req_notifier_handler(void *opaque) 58 { 59 VFIOAPDevice *vapdev = opaque; 60 Error *err = NULL; 61 62 if (!event_notifier_test_and_clear(&vapdev->req_notifier)) { 63 return; 64 } 65 66 qdev_unplug(DEVICE(vapdev), &err); 67 68 if (err) { 69 warn_reportf_err(err, VFIO_MSG_PREFIX, vapdev->vdev.name); 70 } 71 } 72 73 static bool vfio_ap_register_irq_notifier(VFIOAPDevice *vapdev, 74 unsigned int irq, Error **errp) 75 { 76 int fd; 77 size_t argsz; 78 IOHandler *fd_read; 79 EventNotifier *notifier; 80 g_autofree struct vfio_irq_info *irq_info = NULL; 81 VFIODevice *vdev = &vapdev->vdev; 82 83 switch (irq) { 84 case VFIO_AP_REQ_IRQ_INDEX: 85 notifier = &vapdev->req_notifier; 86 fd_read = vfio_ap_req_notifier_handler; 87 break; 88 default: 89 error_setg(errp, "vfio: Unsupported device irq(%d)", irq); 90 return false; 91 } 92 93 if (vdev->num_irqs < irq + 1) { 94 error_setg(errp, "vfio: IRQ %u not available (number of irqs %u)", 95 irq, vdev->num_irqs); 96 return false; 97 } 98 99 argsz = sizeof(*irq_info); 100 irq_info = g_malloc0(argsz); 101 irq_info->index = irq; 102 irq_info->argsz = argsz; 103 104 if (ioctl(vdev->fd, VFIO_DEVICE_GET_IRQ_INFO, 105 irq_info) < 0 || irq_info->count < 1) { 106 error_setg_errno(errp, errno, "vfio: Error getting irq info"); 107 return false; 108 } 109 110 if (event_notifier_init(notifier, 0)) { 111 error_setg_errno(errp, errno, 112 "vfio: Unable to init event notifier for irq (%d)", 113 irq); 114 return false; 115 } 116 117 fd = event_notifier_get_fd(notifier); 118 qemu_set_fd_handler(fd, fd_read, NULL, vapdev); 119 120 if (vfio_set_irq_signaling(vdev, irq, 0, VFIO_IRQ_SET_ACTION_TRIGGER, fd, 121 errp)) { 122 qemu_set_fd_handler(fd, NULL, NULL, vapdev); 123 event_notifier_cleanup(notifier); 124 } 125 126 return true; 127 } 128 129 static void vfio_ap_unregister_irq_notifier(VFIOAPDevice *vapdev, 130 unsigned int irq) 131 { 132 Error *err = NULL; 133 EventNotifier *notifier; 134 135 switch (irq) { 136 case VFIO_AP_REQ_IRQ_INDEX: 137 notifier = &vapdev->req_notifier; 138 break; 139 default: 140 error_report("vfio: Unsupported device irq(%d)", irq); 141 return; 142 } 143 144 if (vfio_set_irq_signaling(&vapdev->vdev, irq, 0, 145 VFIO_IRQ_SET_ACTION_TRIGGER, -1, &err)) { 146 warn_reportf_err(err, VFIO_MSG_PREFIX, vapdev->vdev.name); 147 } 148 149 qemu_set_fd_handler(event_notifier_get_fd(notifier), 150 NULL, NULL, vapdev); 151 event_notifier_cleanup(notifier); 152 } 153 154 static void vfio_ap_realize(DeviceState *dev, Error **errp) 155 { 156 ERRP_GUARD(); 157 int ret; 158 Error *err = NULL; 159 VFIOAPDevice *vapdev = VFIO_AP_DEVICE(dev); 160 VFIODevice *vbasedev = &vapdev->vdev; 161 162 if (vfio_device_get_name(vbasedev, errp) < 0) { 163 return; 164 } 165 166 ret = vfio_attach_device(vbasedev->name, vbasedev, 167 &address_space_memory, errp); 168 if (ret) { 169 goto error; 170 } 171 172 if (!vfio_ap_register_irq_notifier(vapdev, VFIO_AP_REQ_IRQ_INDEX, &err)) { 173 /* 174 * Report this error, but do not make it a failing condition. 175 * Lack of this IRQ in the host does not prevent normal operation. 176 */ 177 error_report_err(err); 178 } 179 180 return; 181 182 error: 183 error_prepend(errp, VFIO_MSG_PREFIX, vbasedev->name); 184 g_free(vbasedev->name); 185 } 186 187 static void vfio_ap_unrealize(DeviceState *dev) 188 { 189 VFIOAPDevice *vapdev = VFIO_AP_DEVICE(dev); 190 191 vfio_ap_unregister_irq_notifier(vapdev, VFIO_AP_REQ_IRQ_INDEX); 192 vfio_detach_device(&vapdev->vdev); 193 g_free(vapdev->vdev.name); 194 } 195 196 static Property vfio_ap_properties[] = { 197 DEFINE_PROP_STRING("sysfsdev", VFIOAPDevice, vdev.sysfsdev), 198 #ifdef CONFIG_IOMMUFD 199 DEFINE_PROP_LINK("iommufd", VFIOAPDevice, vdev.iommufd, 200 TYPE_IOMMUFD_BACKEND, IOMMUFDBackend *), 201 #endif 202 DEFINE_PROP_END_OF_LIST(), 203 }; 204 205 static void vfio_ap_reset(DeviceState *dev) 206 { 207 int ret; 208 VFIOAPDevice *vapdev = VFIO_AP_DEVICE(dev); 209 210 ret = ioctl(vapdev->vdev.fd, VFIO_DEVICE_RESET); 211 if (ret) { 212 error_report("%s: failed to reset %s device: %s", __func__, 213 vapdev->vdev.name, strerror(errno)); 214 } 215 } 216 217 static const VMStateDescription vfio_ap_vmstate = { 218 .name = "vfio-ap", 219 .unmigratable = 1, 220 }; 221 222 static void vfio_ap_instance_init(Object *obj) 223 { 224 VFIOAPDevice *vapdev = VFIO_AP_DEVICE(obj); 225 VFIODevice *vbasedev = &vapdev->vdev; 226 227 /* 228 * vfio-ap devices operate in a way compatible with discarding of 229 * memory in RAM blocks, as no pages are pinned in the host. 230 * This needs to be set before vfio_get_device() for vfio common to 231 * handle ram_block_discard_disable(). 232 */ 233 vfio_device_init(vbasedev, VFIO_DEVICE_TYPE_AP, &vfio_ap_ops, 234 DEVICE(vapdev), true); 235 } 236 237 #ifdef CONFIG_IOMMUFD 238 static void vfio_ap_set_fd(Object *obj, const char *str, Error **errp) 239 { 240 vfio_device_set_fd(&VFIO_AP_DEVICE(obj)->vdev, str, errp); 241 } 242 #endif 243 244 static void vfio_ap_class_init(ObjectClass *klass, void *data) 245 { 246 DeviceClass *dc = DEVICE_CLASS(klass); 247 248 device_class_set_props(dc, vfio_ap_properties); 249 #ifdef CONFIG_IOMMUFD 250 object_class_property_add_str(klass, "fd", NULL, vfio_ap_set_fd); 251 #endif 252 dc->vmsd = &vfio_ap_vmstate; 253 dc->desc = "VFIO-based AP device assignment"; 254 set_bit(DEVICE_CATEGORY_MISC, dc->categories); 255 dc->realize = vfio_ap_realize; 256 dc->unrealize = vfio_ap_unrealize; 257 dc->hotpluggable = true; 258 dc->reset = vfio_ap_reset; 259 dc->bus_type = TYPE_AP_BUS; 260 } 261 262 static const TypeInfo vfio_ap_info = { 263 .name = TYPE_VFIO_AP_DEVICE, 264 .parent = TYPE_AP_DEVICE, 265 .instance_size = sizeof(VFIOAPDevice), 266 .instance_init = vfio_ap_instance_init, 267 .class_init = vfio_ap_class_init, 268 }; 269 270 static void vfio_ap_type_init(void) 271 { 272 type_register_static(&vfio_ap_info); 273 } 274 275 type_init(vfio_ap_type_init) 276