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 <linux/vfio.h> 14 #include <sys/ioctl.h> 15 #include "qemu/osdep.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/queue.h" 23 #include "qemu/option.h" 24 #include "qemu/config-file.h" 25 #include "cpu.h" 26 #include "kvm_s390x.h" 27 #include "sysemu/sysemu.h" 28 #include "hw/s390x/ap-bridge.h" 29 #include "exec/address-spaces.h" 30 31 #define VFIO_AP_DEVICE_TYPE "vfio-ap" 32 33 typedef struct VFIOAPDevice { 34 APDevice apdev; 35 VFIODevice vdev; 36 } VFIOAPDevice; 37 38 #define VFIO_AP_DEVICE(obj) \ 39 OBJECT_CHECK(VFIOAPDevice, (obj), VFIO_AP_DEVICE_TYPE) 40 41 static void vfio_ap_compute_needs_reset(VFIODevice *vdev) 42 { 43 vdev->needs_reset = false; 44 } 45 46 /* 47 * We don't need vfio_hot_reset_multi and vfio_eoi operations for 48 * vfio-ap device now. 49 */ 50 struct VFIODeviceOps vfio_ap_ops = { 51 .vfio_compute_needs_reset = vfio_ap_compute_needs_reset, 52 }; 53 54 static void vfio_ap_put_device(VFIOAPDevice *vapdev) 55 { 56 g_free(vapdev->vdev.name); 57 vfio_put_base_device(&vapdev->vdev); 58 } 59 60 static VFIOGroup *vfio_ap_get_group(VFIOAPDevice *vapdev, Error **errp) 61 { 62 GError *gerror = NULL; 63 char *symlink, *group_path; 64 int groupid; 65 66 symlink = g_strdup_printf("%s/iommu_group", vapdev->vdev.sysfsdev); 67 group_path = g_file_read_link(symlink, &gerror); 68 g_free(symlink); 69 70 if (!group_path) { 71 error_setg(errp, "%s: no iommu_group found for %s: %s", 72 VFIO_AP_DEVICE_TYPE, vapdev->vdev.sysfsdev, gerror->message); 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 Error *local_err = NULL; 92 VFIOGroup *vfio_group; 93 APDevice *apdev = AP_DEVICE(dev); 94 VFIOAPDevice *vapdev = VFIO_AP_DEVICE(apdev); 95 96 vfio_group = vfio_ap_get_group(vapdev, &local_err); 97 if (!vfio_group) { 98 goto out_err; 99 } 100 101 vapdev->vdev.ops = &vfio_ap_ops; 102 vapdev->vdev.type = VFIO_DEVICE_TYPE_AP; 103 mdevid = basename(vapdev->vdev.sysfsdev); 104 vapdev->vdev.name = g_strdup_printf("%s", mdevid); 105 vapdev->vdev.dev = dev; 106 107 /* 108 * vfio-ap devices operate in a way compatible with 109 * memory ballooning, as no pages are pinned in the host. 110 * This needs to be set before vfio_get_device() for vfio common to 111 * handle the balloon inhibitor. 112 */ 113 vapdev->vdev.balloon_allowed = true; 114 115 ret = vfio_get_device(vfio_group, mdevid, &vapdev->vdev, &local_err); 116 if (ret) { 117 goto out_get_dev_err; 118 } 119 120 return; 121 122 out_get_dev_err: 123 vfio_ap_put_device(vapdev); 124 vfio_put_group(vfio_group); 125 out_err: 126 error_propagate(errp, local_err); 127 } 128 129 static void vfio_ap_unrealize(DeviceState *dev, Error **errp) 130 { 131 APDevice *apdev = AP_DEVICE(dev); 132 VFIOAPDevice *vapdev = VFIO_AP_DEVICE(apdev); 133 VFIOGroup *group = vapdev->vdev.group; 134 135 vfio_ap_put_device(vapdev); 136 vfio_put_group(group); 137 } 138 139 static Property vfio_ap_properties[] = { 140 DEFINE_PROP_STRING("sysfsdev", VFIOAPDevice, vdev.sysfsdev), 141 DEFINE_PROP_END_OF_LIST(), 142 }; 143 144 static void vfio_ap_reset(DeviceState *dev) 145 { 146 int ret; 147 APDevice *apdev = AP_DEVICE(dev); 148 VFIOAPDevice *vapdev = VFIO_AP_DEVICE(apdev); 149 150 ret = ioctl(vapdev->vdev.fd, VFIO_DEVICE_RESET); 151 if (ret) { 152 error_report("%s: failed to reset %s device: %s", __func__, 153 vapdev->vdev.name, strerror(errno)); 154 } 155 } 156 157 static const VMStateDescription vfio_ap_vmstate = { 158 .name = VFIO_AP_DEVICE_TYPE, 159 .unmigratable = 1, 160 }; 161 162 static void vfio_ap_class_init(ObjectClass *klass, void *data) 163 { 164 DeviceClass *dc = DEVICE_CLASS(klass); 165 166 dc->props = vfio_ap_properties; 167 dc->vmsd = &vfio_ap_vmstate; 168 dc->desc = "VFIO-based AP device assignment"; 169 set_bit(DEVICE_CATEGORY_MISC, dc->categories); 170 dc->realize = vfio_ap_realize; 171 dc->unrealize = vfio_ap_unrealize; 172 dc->hotpluggable = false; 173 dc->reset = vfio_ap_reset; 174 dc->bus_type = TYPE_AP_BUS; 175 } 176 177 static const TypeInfo vfio_ap_info = { 178 .name = VFIO_AP_DEVICE_TYPE, 179 .parent = AP_DEVICE_TYPE, 180 .instance_size = sizeof(VFIOAPDevice), 181 .class_init = vfio_ap_class_init, 182 }; 183 184 static void vfio_ap_type_init(void) 185 { 186 type_register_static(&vfio_ap_info); 187 } 188 189 type_init(vfio_ap_type_init) 190