1 /* 2 * vhost_scsi host device 3 * 4 * Copyright IBM, Corp. 2011 5 * 6 * Authors: 7 * Stefan Hajnoczi <stefanha@linux.vnet.ibm.com> 8 * 9 * Changes for QEMU mainline + tcm_vhost kernel upstream: 10 * Nicholas Bellinger <nab@risingtidesystems.com> 11 * 12 * This work is licensed under the terms of the GNU LGPL, version 2 or later. 13 * See the COPYING.LIB file in the top-level directory. 14 * 15 */ 16 17 #include "qemu/osdep.h" 18 #include <linux/vhost.h> 19 #include <sys/ioctl.h> 20 #include "qapi/error.h" 21 #include "qemu/error-report.h" 22 #include "qemu/queue.h" 23 #include "monitor/monitor.h" 24 #include "migration/blocker.h" 25 #include "hw/virtio/vhost-scsi.h" 26 #include "hw/virtio/vhost.h" 27 #include "hw/virtio/virtio-scsi.h" 28 #include "hw/virtio/virtio-bus.h" 29 #include "hw/virtio/virtio-access.h" 30 #include "hw/fw-path-provider.h" 31 #include "qemu/cutils.h" 32 33 /* Features supported by host kernel. */ 34 static const int kernel_feature_bits[] = { 35 VIRTIO_F_NOTIFY_ON_EMPTY, 36 VIRTIO_RING_F_INDIRECT_DESC, 37 VIRTIO_RING_F_EVENT_IDX, 38 VIRTIO_SCSI_F_HOTPLUG, 39 VHOST_INVALID_FEATURE_BIT 40 }; 41 42 static int vhost_scsi_set_endpoint(VHostSCSI *s) 43 { 44 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(s); 45 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); 46 const VhostOps *vhost_ops = vsc->dev.vhost_ops; 47 struct vhost_scsi_target backend; 48 int ret; 49 50 memset(&backend, 0, sizeof(backend)); 51 pstrcpy(backend.vhost_wwpn, sizeof(backend.vhost_wwpn), vs->conf.wwpn); 52 ret = vhost_ops->vhost_scsi_set_endpoint(&vsc->dev, &backend); 53 if (ret < 0) { 54 return -errno; 55 } 56 return 0; 57 } 58 59 static void vhost_scsi_clear_endpoint(VHostSCSI *s) 60 { 61 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(s); 62 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); 63 struct vhost_scsi_target backend; 64 const VhostOps *vhost_ops = vsc->dev.vhost_ops; 65 66 memset(&backend, 0, sizeof(backend)); 67 pstrcpy(backend.vhost_wwpn, sizeof(backend.vhost_wwpn), vs->conf.wwpn); 68 vhost_ops->vhost_scsi_clear_endpoint(&vsc->dev, &backend); 69 } 70 71 static int vhost_scsi_start(VHostSCSI *s) 72 { 73 int ret, abi_version; 74 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); 75 const VhostOps *vhost_ops = vsc->dev.vhost_ops; 76 77 ret = vhost_ops->vhost_scsi_get_abi_version(&vsc->dev, &abi_version); 78 if (ret < 0) { 79 return -errno; 80 } 81 if (abi_version > VHOST_SCSI_ABI_VERSION) { 82 error_report("vhost-scsi: The running tcm_vhost kernel abi_version:" 83 " %d is greater than vhost_scsi userspace supports: %d," 84 " please upgrade your version of QEMU", abi_version, 85 VHOST_SCSI_ABI_VERSION); 86 return -ENOSYS; 87 } 88 89 ret = vhost_scsi_common_start(vsc); 90 if (ret < 0) { 91 return ret; 92 } 93 94 ret = vhost_scsi_set_endpoint(s); 95 if (ret < 0) { 96 error_report("Error setting vhost-scsi endpoint"); 97 vhost_scsi_common_stop(vsc); 98 } 99 100 return ret; 101 } 102 103 static void vhost_scsi_stop(VHostSCSI *s) 104 { 105 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); 106 107 vhost_scsi_clear_endpoint(s); 108 vhost_scsi_common_stop(vsc); 109 } 110 111 static void vhost_scsi_set_status(VirtIODevice *vdev, uint8_t val) 112 { 113 VHostSCSI *s = VHOST_SCSI(vdev); 114 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); 115 bool start = (val & VIRTIO_CONFIG_S_DRIVER_OK); 116 117 if (vsc->dev.started == start) { 118 return; 119 } 120 121 if (start) { 122 int ret; 123 124 ret = vhost_scsi_start(s); 125 if (ret < 0) { 126 error_report("unable to start vhost-scsi: %s", strerror(-ret)); 127 exit(1); 128 } 129 } else { 130 vhost_scsi_stop(s); 131 } 132 } 133 134 static void vhost_dummy_handle_output(VirtIODevice *vdev, VirtQueue *vq) 135 { 136 } 137 138 static void vhost_scsi_realize(DeviceState *dev, Error **errp) 139 { 140 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); 141 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(dev); 142 Error *err = NULL; 143 int vhostfd = -1; 144 int ret; 145 146 if (!vs->conf.wwpn) { 147 error_setg(errp, "vhost-scsi: missing wwpn"); 148 return; 149 } 150 151 if (vs->conf.vhostfd) { 152 vhostfd = monitor_fd_param(cur_mon, vs->conf.vhostfd, errp); 153 if (vhostfd == -1) { 154 error_prepend(errp, "vhost-scsi: unable to parse vhostfd: "); 155 return; 156 } 157 } else { 158 vhostfd = open("/dev/vhost-scsi", O_RDWR); 159 if (vhostfd < 0) { 160 error_setg(errp, "vhost-scsi: open vhost char device failed: %s", 161 strerror(errno)); 162 return; 163 } 164 } 165 166 virtio_scsi_common_realize(dev, 167 vhost_dummy_handle_output, 168 vhost_dummy_handle_output, 169 vhost_dummy_handle_output, 170 &err); 171 if (err != NULL) { 172 error_propagate(errp, err); 173 goto close_fd; 174 } 175 176 error_setg(&vsc->migration_blocker, 177 "vhost-scsi does not support migration"); 178 migrate_add_blocker(vsc->migration_blocker, &err); 179 if (err) { 180 error_propagate(errp, err); 181 error_free(vsc->migration_blocker); 182 goto close_fd; 183 } 184 185 vsc->dev.nvqs = VHOST_SCSI_VQ_NUM_FIXED + vs->conf.num_queues; 186 vsc->dev.vqs = g_new(struct vhost_virtqueue, vsc->dev.nvqs); 187 vsc->dev.vq_index = 0; 188 vsc->dev.backend_features = 0; 189 190 ret = vhost_dev_init(&vsc->dev, (void *)(uintptr_t)vhostfd, 191 VHOST_BACKEND_TYPE_KERNEL, 0); 192 if (ret < 0) { 193 error_setg(errp, "vhost-scsi: vhost initialization failed: %s", 194 strerror(-ret)); 195 goto free_vqs; 196 } 197 198 /* At present, channel and lun both are 0 for bootable vhost-scsi disk */ 199 vsc->channel = 0; 200 vsc->lun = 0; 201 /* Note: we can also get the minimum tpgt from kernel */ 202 vsc->target = vs->conf.boot_tpgt; 203 204 return; 205 206 free_vqs: 207 migrate_del_blocker(vsc->migration_blocker); 208 g_free(vsc->dev.vqs); 209 close_fd: 210 close(vhostfd); 211 return; 212 } 213 214 static void vhost_scsi_unrealize(DeviceState *dev, Error **errp) 215 { 216 VirtIODevice *vdev = VIRTIO_DEVICE(dev); 217 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(dev); 218 219 migrate_del_blocker(vsc->migration_blocker); 220 error_free(vsc->migration_blocker); 221 222 /* This will stop vhost backend. */ 223 vhost_scsi_set_status(vdev, 0); 224 225 vhost_dev_cleanup(&vsc->dev); 226 g_free(vsc->dev.vqs); 227 228 virtio_scsi_common_unrealize(dev, errp); 229 } 230 231 static Property vhost_scsi_properties[] = { 232 DEFINE_PROP_STRING("vhostfd", VirtIOSCSICommon, conf.vhostfd), 233 DEFINE_PROP_STRING("wwpn", VirtIOSCSICommon, conf.wwpn), 234 DEFINE_PROP_UINT32("boot_tpgt", VirtIOSCSICommon, conf.boot_tpgt, 0), 235 DEFINE_PROP_UINT32("num_queues", VirtIOSCSICommon, conf.num_queues, 1), 236 DEFINE_PROP_UINT32("max_sectors", VirtIOSCSICommon, conf.max_sectors, 237 0xFFFF), 238 DEFINE_PROP_UINT32("cmd_per_lun", VirtIOSCSICommon, conf.cmd_per_lun, 128), 239 DEFINE_PROP_END_OF_LIST(), 240 }; 241 242 static void vhost_scsi_class_init(ObjectClass *klass, void *data) 243 { 244 DeviceClass *dc = DEVICE_CLASS(klass); 245 VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass); 246 FWPathProviderClass *fwc = FW_PATH_PROVIDER_CLASS(klass); 247 248 dc->props = vhost_scsi_properties; 249 set_bit(DEVICE_CATEGORY_STORAGE, dc->categories); 250 vdc->realize = vhost_scsi_realize; 251 vdc->unrealize = vhost_scsi_unrealize; 252 vdc->get_features = vhost_scsi_common_get_features; 253 vdc->set_config = vhost_scsi_common_set_config; 254 vdc->set_status = vhost_scsi_set_status; 255 fwc->get_dev_path = vhost_scsi_common_get_fw_dev_path; 256 } 257 258 static void vhost_scsi_instance_init(Object *obj) 259 { 260 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(obj); 261 262 vsc->feature_bits = kernel_feature_bits; 263 264 device_add_bootindex_property(obj, &vsc->bootindex, "bootindex", NULL, 265 DEVICE(vsc), NULL); 266 } 267 268 static const TypeInfo vhost_scsi_info = { 269 .name = TYPE_VHOST_SCSI, 270 .parent = TYPE_VHOST_SCSI_COMMON, 271 .instance_size = sizeof(VHostSCSI), 272 .class_init = vhost_scsi_class_init, 273 .instance_init = vhost_scsi_instance_init, 274 .interfaces = (InterfaceInfo[]) { 275 { TYPE_FW_PATH_PROVIDER }, 276 { } 277 }, 278 }; 279 280 static void virtio_register_types(void) 281 { 282 type_register_static(&vhost_scsi_info); 283 } 284 285 type_init(virtio_register_types) 286