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