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 32 #define VFIO_AP_DEVICE_TYPE "vfio-ap" 33 34 typedef struct VFIOAPDevice { 35 APDevice apdev; 36 VFIODevice vdev; 37 } VFIOAPDevice; 38 39 #define VFIO_AP_DEVICE(obj) \ 40 OBJECT_CHECK(VFIOAPDevice, (obj), VFIO_AP_DEVICE_TYPE) 41 42 static void vfio_ap_compute_needs_reset(VFIODevice *vdev) 43 { 44 vdev->needs_reset = false; 45 } 46 47 /* 48 * We don't need vfio_hot_reset_multi and vfio_eoi operations for 49 * vfio-ap device now. 50 */ 51 struct VFIODeviceOps vfio_ap_ops = { 52 .vfio_compute_needs_reset = vfio_ap_compute_needs_reset, 53 }; 54 55 static void vfio_ap_put_device(VFIOAPDevice *vapdev) 56 { 57 g_free(vapdev->vdev.name); 58 vfio_put_base_device(&vapdev->vdev); 59 } 60 61 static VFIOGroup *vfio_ap_get_group(VFIOAPDevice *vapdev, Error **errp) 62 { 63 GError *gerror = NULL; 64 char *symlink, *group_path; 65 int groupid; 66 67 symlink = g_strdup_printf("%s/iommu_group", vapdev->vdev.sysfsdev); 68 group_path = g_file_read_link(symlink, &gerror); 69 g_free(symlink); 70 71 if (!group_path) { 72 error_setg(errp, "%s: no iommu_group found for %s: %s", 73 VFIO_AP_DEVICE_TYPE, vapdev->vdev.sysfsdev, gerror->message); 74 g_error_free(gerror); 75 return NULL; 76 } 77 78 if (sscanf(basename(group_path), "%d", &groupid) != 1) { 79 error_setg(errp, "vfio: failed to read %s", group_path); 80 g_free(group_path); 81 return NULL; 82 } 83 84 g_free(group_path); 85 86 return vfio_get_group(groupid, &address_space_memory, errp); 87 } 88 89 static void vfio_ap_realize(DeviceState *dev, Error **errp) 90 { 91 int ret; 92 char *mdevid; 93 VFIOGroup *vfio_group; 94 APDevice *apdev = AP_DEVICE(dev); 95 VFIOAPDevice *vapdev = VFIO_AP_DEVICE(apdev); 96 97 vfio_group = vfio_ap_get_group(vapdev, errp); 98 if (!vfio_group) { 99 return; 100 } 101 102 vapdev->vdev.ops = &vfio_ap_ops; 103 vapdev->vdev.type = VFIO_DEVICE_TYPE_AP; 104 mdevid = basename(vapdev->vdev.sysfsdev); 105 vapdev->vdev.name = g_strdup_printf("%s", mdevid); 106 vapdev->vdev.dev = dev; 107 108 /* 109 * vfio-ap devices operate in a way compatible with discarding of 110 * memory in RAM blocks, as no pages are pinned in the host. 111 * This needs to be set before vfio_get_device() for vfio common to 112 * handle ram_block_discard_disable(). 113 */ 114 vapdev->vdev.ram_block_discard_allowed = true; 115 116 ret = vfio_get_device(vfio_group, mdevid, &vapdev->vdev, errp); 117 if (ret) { 118 goto out_get_dev_err; 119 } 120 121 return; 122 123 out_get_dev_err: 124 vfio_ap_put_device(vapdev); 125 vfio_put_group(vfio_group); 126 } 127 128 static void vfio_ap_unrealize(DeviceState *dev) 129 { 130 APDevice *apdev = AP_DEVICE(dev); 131 VFIOAPDevice *vapdev = VFIO_AP_DEVICE(apdev); 132 VFIOGroup *group = vapdev->vdev.group; 133 134 vfio_ap_put_device(vapdev); 135 vfio_put_group(group); 136 } 137 138 static Property vfio_ap_properties[] = { 139 DEFINE_PROP_STRING("sysfsdev", VFIOAPDevice, vdev.sysfsdev), 140 DEFINE_PROP_END_OF_LIST(), 141 }; 142 143 static void vfio_ap_reset(DeviceState *dev) 144 { 145 int ret; 146 APDevice *apdev = AP_DEVICE(dev); 147 VFIOAPDevice *vapdev = VFIO_AP_DEVICE(apdev); 148 149 ret = ioctl(vapdev->vdev.fd, VFIO_DEVICE_RESET); 150 if (ret) { 151 error_report("%s: failed to reset %s device: %s", __func__, 152 vapdev->vdev.name, strerror(errno)); 153 } 154 } 155 156 static const VMStateDescription vfio_ap_vmstate = { 157 .name = "vfio-ap", 158 .unmigratable = 1, 159 }; 160 161 static void vfio_ap_class_init(ObjectClass *klass, void *data) 162 { 163 DeviceClass *dc = DEVICE_CLASS(klass); 164 165 device_class_set_props(dc, vfio_ap_properties); 166 dc->vmsd = &vfio_ap_vmstate; 167 dc->desc = "VFIO-based AP device assignment"; 168 set_bit(DEVICE_CATEGORY_MISC, dc->categories); 169 dc->realize = vfio_ap_realize; 170 dc->unrealize = vfio_ap_unrealize; 171 dc->hotpluggable = true; 172 dc->reset = vfio_ap_reset; 173 dc->bus_type = TYPE_AP_BUS; 174 } 175 176 static const TypeInfo vfio_ap_info = { 177 .name = VFIO_AP_DEVICE_TYPE, 178 .parent = AP_DEVICE_TYPE, 179 .instance_size = sizeof(VFIOAPDevice), 180 .class_init = vfio_ap_class_init, 181 }; 182 183 static void vfio_ap_type_init(void) 184 { 185 type_register_static(&vfio_ap_info); 186 } 187 188 type_init(vfio_ap_type_init) 189