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 Error *err = NULL; 158 VFIOAPDevice *vapdev = VFIO_AP_DEVICE(dev); 159 VFIODevice *vbasedev = &vapdev->vdev; 160 161 if (!vfio_device_get_name(vbasedev, errp)) { 162 return; 163 } 164 165 if (!vfio_attach_device(vbasedev->name, vbasedev, 166 &address_space_memory, errp)) { 167 goto error; 168 } 169 170 if (!vfio_ap_register_irq_notifier(vapdev, VFIO_AP_REQ_IRQ_INDEX, &err)) { 171 /* 172 * Report this error, but do not make it a failing condition. 173 * Lack of this IRQ in the host does not prevent normal operation. 174 */ 175 warn_report_err(err); 176 } 177 178 return; 179 180 error: 181 error_prepend(errp, VFIO_MSG_PREFIX, vbasedev->name); 182 g_free(vbasedev->name); 183 } 184 185 static void vfio_ap_unrealize(DeviceState *dev) 186 { 187 VFIOAPDevice *vapdev = VFIO_AP_DEVICE(dev); 188 189 vfio_ap_unregister_irq_notifier(vapdev, VFIO_AP_REQ_IRQ_INDEX); 190 vfio_detach_device(&vapdev->vdev); 191 g_free(vapdev->vdev.name); 192 } 193 194 static Property vfio_ap_properties[] = { 195 DEFINE_PROP_STRING("sysfsdev", VFIOAPDevice, vdev.sysfsdev), 196 #ifdef CONFIG_IOMMUFD 197 DEFINE_PROP_LINK("iommufd", VFIOAPDevice, vdev.iommufd, 198 TYPE_IOMMUFD_BACKEND, IOMMUFDBackend *), 199 #endif 200 DEFINE_PROP_END_OF_LIST(), 201 }; 202 203 static void vfio_ap_reset(DeviceState *dev) 204 { 205 int ret; 206 VFIOAPDevice *vapdev = VFIO_AP_DEVICE(dev); 207 208 ret = ioctl(vapdev->vdev.fd, VFIO_DEVICE_RESET); 209 if (ret) { 210 error_report("%s: failed to reset %s device: %s", __func__, 211 vapdev->vdev.name, strerror(errno)); 212 } 213 } 214 215 static const VMStateDescription vfio_ap_vmstate = { 216 .name = "vfio-ap", 217 .unmigratable = 1, 218 }; 219 220 static void vfio_ap_instance_init(Object *obj) 221 { 222 VFIOAPDevice *vapdev = VFIO_AP_DEVICE(obj); 223 VFIODevice *vbasedev = &vapdev->vdev; 224 225 /* 226 * vfio-ap devices operate in a way compatible with discarding of 227 * memory in RAM blocks, as no pages are pinned in the host. 228 * This needs to be set before vfio_get_device() for vfio common to 229 * handle ram_block_discard_disable(). 230 */ 231 vfio_device_init(vbasedev, VFIO_DEVICE_TYPE_AP, &vfio_ap_ops, 232 DEVICE(vapdev), true); 233 } 234 235 #ifdef CONFIG_IOMMUFD 236 static void vfio_ap_set_fd(Object *obj, const char *str, Error **errp) 237 { 238 vfio_device_set_fd(&VFIO_AP_DEVICE(obj)->vdev, str, errp); 239 } 240 #endif 241 242 static void vfio_ap_class_init(ObjectClass *klass, void *data) 243 { 244 DeviceClass *dc = DEVICE_CLASS(klass); 245 246 device_class_set_props(dc, vfio_ap_properties); 247 #ifdef CONFIG_IOMMUFD 248 object_class_property_add_str(klass, "fd", NULL, vfio_ap_set_fd); 249 #endif 250 dc->vmsd = &vfio_ap_vmstate; 251 dc->desc = "VFIO-based AP device assignment"; 252 set_bit(DEVICE_CATEGORY_MISC, dc->categories); 253 dc->realize = vfio_ap_realize; 254 dc->unrealize = vfio_ap_unrealize; 255 dc->hotpluggable = true; 256 dc->reset = vfio_ap_reset; 257 dc->bus_type = TYPE_AP_BUS; 258 } 259 260 static const TypeInfo vfio_ap_info = { 261 .name = TYPE_VFIO_AP_DEVICE, 262 .parent = TYPE_AP_DEVICE, 263 .instance_size = sizeof(VFIOAPDevice), 264 .instance_init = vfio_ap_instance_init, 265 .class_init = vfio_ap_class_init, 266 }; 267 268 static void vfio_ap_type_init(void) 269 { 270 type_register_static(&vfio_ap_info); 271 } 272 273 type_init(vfio_ap_type_init) 274