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/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/module.h" 23 #include "qemu/option.h" 24 #include "qemu/config-file.h" 25 #include "cpu.h" 26 #include "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 }; 39 typedef struct VFIOAPDevice VFIOAPDevice; 40 41 DECLARE_INSTANCE_CHECKER(VFIOAPDevice, VFIO_AP_DEVICE, 42 TYPE_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_put_device(VFIOAPDevice *vapdev) 58 { 59 g_free(vapdev->vdev.name); 60 vfio_put_base_device(&vapdev->vdev); 61 } 62 63 static VFIOGroup *vfio_ap_get_group(VFIOAPDevice *vapdev, Error **errp) 64 { 65 GError *gerror = NULL; 66 char *symlink, *group_path; 67 int groupid; 68 69 symlink = g_strdup_printf("%s/iommu_group", vapdev->vdev.sysfsdev); 70 group_path = g_file_read_link(symlink, &gerror); 71 g_free(symlink); 72 73 if (!group_path) { 74 error_setg(errp, "%s: no iommu_group found for %s: %s", 75 TYPE_VFIO_AP_DEVICE, vapdev->vdev.sysfsdev, gerror->message); 76 g_error_free(gerror); 77 return NULL; 78 } 79 80 if (sscanf(basename(group_path), "%d", &groupid) != 1) { 81 error_setg(errp, "vfio: failed to read %s", group_path); 82 g_free(group_path); 83 return NULL; 84 } 85 86 g_free(group_path); 87 88 return vfio_get_group(groupid, &address_space_memory, errp); 89 } 90 91 static void vfio_ap_realize(DeviceState *dev, Error **errp) 92 { 93 int ret; 94 char *mdevid; 95 VFIOGroup *vfio_group; 96 APDevice *apdev = AP_DEVICE(dev); 97 VFIOAPDevice *vapdev = VFIO_AP_DEVICE(apdev); 98 99 vfio_group = vfio_ap_get_group(vapdev, errp); 100 if (!vfio_group) { 101 return; 102 } 103 104 vapdev->vdev.ops = &vfio_ap_ops; 105 vapdev->vdev.type = VFIO_DEVICE_TYPE_AP; 106 mdevid = basename(vapdev->vdev.sysfsdev); 107 vapdev->vdev.name = g_strdup_printf("%s", mdevid); 108 vapdev->vdev.dev = dev; 109 110 /* 111 * vfio-ap devices operate in a way compatible with discarding of 112 * memory in RAM blocks, as no pages are pinned in the host. 113 * This needs to be set before vfio_get_device() for vfio common to 114 * handle ram_block_discard_disable(). 115 */ 116 vapdev->vdev.ram_block_discard_allowed = true; 117 118 ret = vfio_get_device(vfio_group, mdevid, &vapdev->vdev, errp); 119 if (ret) { 120 goto out_get_dev_err; 121 } 122 123 return; 124 125 out_get_dev_err: 126 vfio_ap_put_device(vapdev); 127 vfio_put_group(vfio_group); 128 } 129 130 static void vfio_ap_unrealize(DeviceState *dev) 131 { 132 APDevice *apdev = AP_DEVICE(dev); 133 VFIOAPDevice *vapdev = VFIO_AP_DEVICE(apdev); 134 VFIOGroup *group = vapdev->vdev.group; 135 136 vfio_ap_put_device(vapdev); 137 vfio_put_group(group); 138 } 139 140 static Property vfio_ap_properties[] = { 141 DEFINE_PROP_STRING("sysfsdev", VFIOAPDevice, vdev.sysfsdev), 142 DEFINE_PROP_END_OF_LIST(), 143 }; 144 145 static void vfio_ap_reset(DeviceState *dev) 146 { 147 int ret; 148 APDevice *apdev = AP_DEVICE(dev); 149 VFIOAPDevice *vapdev = VFIO_AP_DEVICE(apdev); 150 151 ret = ioctl(vapdev->vdev.fd, VFIO_DEVICE_RESET); 152 if (ret) { 153 error_report("%s: failed to reset %s device: %s", __func__, 154 vapdev->vdev.name, strerror(errno)); 155 } 156 } 157 158 static const VMStateDescription vfio_ap_vmstate = { 159 .name = "vfio-ap", 160 .unmigratable = 1, 161 }; 162 163 static void vfio_ap_class_init(ObjectClass *klass, void *data) 164 { 165 DeviceClass *dc = DEVICE_CLASS(klass); 166 167 device_class_set_props(dc, vfio_ap_properties); 168 dc->vmsd = &vfio_ap_vmstate; 169 dc->desc = "VFIO-based AP device assignment"; 170 set_bit(DEVICE_CATEGORY_MISC, dc->categories); 171 dc->realize = vfio_ap_realize; 172 dc->unrealize = vfio_ap_unrealize; 173 dc->hotpluggable = true; 174 dc->reset = vfio_ap_reset; 175 dc->bus_type = TYPE_AP_BUS; 176 } 177 178 static const TypeInfo vfio_ap_info = { 179 .name = TYPE_VFIO_AP_DEVICE, 180 .parent = TYPE_AP_DEVICE, 181 .instance_size = sizeof(VFIOAPDevice), 182 .class_init = vfio_ap_class_init, 183 }; 184 185 static void vfio_ap_type_init(void) 186 { 187 type_register_static(&vfio_ap_info); 188 } 189 190 type_init(vfio_ap_type_init) 191