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/module.h" 22 #include "qemu/option.h" 23 #include "qemu/config-file.h" 24 #include "kvm_s390x.h" 25 #include "migration/vmstate.h" 26 #include "hw/qdev-properties.h" 27 #include "hw/s390x/ap-bridge.h" 28 #include "exec/address-spaces.h" 29 #include "qom/object.h" 30 31 #define TYPE_VFIO_AP_DEVICE "vfio-ap" 32 33 struct VFIOAPDevice { 34 APDevice apdev; 35 VFIODevice vdev; 36 }; 37 38 OBJECT_DECLARE_SIMPLE_TYPE(VFIOAPDevice, VFIO_AP_DEVICE) 39 40 static void vfio_ap_compute_needs_reset(VFIODevice *vdev) 41 { 42 vdev->needs_reset = false; 43 } 44 45 /* 46 * We don't need vfio_hot_reset_multi and vfio_eoi operations for 47 * vfio-ap device now. 48 */ 49 struct VFIODeviceOps vfio_ap_ops = { 50 .vfio_compute_needs_reset = vfio_ap_compute_needs_reset, 51 }; 52 53 static void vfio_ap_put_device(VFIOAPDevice *vapdev) 54 { 55 g_free(vapdev->vdev.name); 56 vfio_put_base_device(&vapdev->vdev); 57 } 58 59 static VFIOGroup *vfio_ap_get_group(VFIOAPDevice *vapdev, Error **errp) 60 { 61 GError *gerror = NULL; 62 char *symlink, *group_path; 63 int groupid; 64 65 symlink = g_strdup_printf("%s/iommu_group", vapdev->vdev.sysfsdev); 66 group_path = g_file_read_link(symlink, &gerror); 67 g_free(symlink); 68 69 if (!group_path) { 70 error_setg(errp, "%s: no iommu_group found for %s: %s", 71 TYPE_VFIO_AP_DEVICE, vapdev->vdev.sysfsdev, gerror->message); 72 g_error_free(gerror); 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 VFIOGroup *vfio_group; 92 APDevice *apdev = AP_DEVICE(dev); 93 VFIOAPDevice *vapdev = VFIO_AP_DEVICE(apdev); 94 95 vfio_group = vfio_ap_get_group(vapdev, errp); 96 if (!vfio_group) { 97 return; 98 } 99 100 vapdev->vdev.ops = &vfio_ap_ops; 101 vapdev->vdev.type = VFIO_DEVICE_TYPE_AP; 102 mdevid = basename(vapdev->vdev.sysfsdev); 103 vapdev->vdev.name = g_strdup_printf("%s", mdevid); 104 vapdev->vdev.dev = dev; 105 106 /* 107 * vfio-ap devices operate in a way compatible with discarding of 108 * memory in RAM blocks, as no pages are pinned in the host. 109 * This needs to be set before vfio_get_device() for vfio common to 110 * handle ram_block_discard_disable(). 111 */ 112 vapdev->vdev.ram_block_discard_allowed = true; 113 114 ret = vfio_get_device(vfio_group, mdevid, &vapdev->vdev, errp); 115 if (ret) { 116 goto out_get_dev_err; 117 } 118 119 return; 120 121 out_get_dev_err: 122 vfio_ap_put_device(vapdev); 123 vfio_put_group(vfio_group); 124 } 125 126 static void vfio_ap_unrealize(DeviceState *dev) 127 { 128 APDevice *apdev = AP_DEVICE(dev); 129 VFIOAPDevice *vapdev = VFIO_AP_DEVICE(apdev); 130 VFIOGroup *group = vapdev->vdev.group; 131 132 vfio_ap_put_device(vapdev); 133 vfio_put_group(group); 134 } 135 136 static Property vfio_ap_properties[] = { 137 DEFINE_PROP_STRING("sysfsdev", VFIOAPDevice, vdev.sysfsdev), 138 DEFINE_PROP_END_OF_LIST(), 139 }; 140 141 static void vfio_ap_reset(DeviceState *dev) 142 { 143 int ret; 144 APDevice *apdev = AP_DEVICE(dev); 145 VFIOAPDevice *vapdev = VFIO_AP_DEVICE(apdev); 146 147 ret = ioctl(vapdev->vdev.fd, VFIO_DEVICE_RESET); 148 if (ret) { 149 error_report("%s: failed to reset %s device: %s", __func__, 150 vapdev->vdev.name, strerror(errno)); 151 } 152 } 153 154 static const VMStateDescription vfio_ap_vmstate = { 155 .name = "vfio-ap", 156 .unmigratable = 1, 157 }; 158 159 static void vfio_ap_class_init(ObjectClass *klass, void *data) 160 { 161 DeviceClass *dc = DEVICE_CLASS(klass); 162 163 device_class_set_props(dc, vfio_ap_properties); 164 dc->vmsd = &vfio_ap_vmstate; 165 dc->desc = "VFIO-based AP device assignment"; 166 set_bit(DEVICE_CATEGORY_MISC, dc->categories); 167 dc->realize = vfio_ap_realize; 168 dc->unrealize = vfio_ap_unrealize; 169 dc->hotpluggable = true; 170 dc->reset = vfio_ap_reset; 171 dc->bus_type = TYPE_AP_BUS; 172 } 173 174 static const TypeInfo vfio_ap_info = { 175 .name = TYPE_VFIO_AP_DEVICE, 176 .parent = TYPE_AP_DEVICE, 177 .instance_size = sizeof(VFIOAPDevice), 178 .class_init = vfio_ap_class_init, 179 }; 180 181 static void vfio_ap_type_init(void) 182 { 183 type_register_static(&vfio_ap_info); 184 } 185 186 type_init(vfio_ap_type_init) 187