vhost-scsi.c (9798B)
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/module.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 "hw/qdev-properties.h" 32#include "qemu/cutils.h" 33#include "sysemu/sysemu.h" 34 35/* Features supported by host kernel. */ 36static const int kernel_feature_bits[] = { 37 VIRTIO_F_NOTIFY_ON_EMPTY, 38 VIRTIO_RING_F_INDIRECT_DESC, 39 VIRTIO_RING_F_EVENT_IDX, 40 VIRTIO_SCSI_F_HOTPLUG, 41 VHOST_INVALID_FEATURE_BIT 42}; 43 44static int vhost_scsi_set_endpoint(VHostSCSI *s) 45{ 46 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(s); 47 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); 48 const VhostOps *vhost_ops = vsc->dev.vhost_ops; 49 struct vhost_scsi_target backend; 50 int ret; 51 52 memset(&backend, 0, sizeof(backend)); 53 pstrcpy(backend.vhost_wwpn, sizeof(backend.vhost_wwpn), vs->conf.wwpn); 54 ret = vhost_ops->vhost_scsi_set_endpoint(&vsc->dev, &backend); 55 if (ret < 0) { 56 return -errno; 57 } 58 return 0; 59} 60 61static void vhost_scsi_clear_endpoint(VHostSCSI *s) 62{ 63 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(s); 64 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); 65 struct vhost_scsi_target backend; 66 const VhostOps *vhost_ops = vsc->dev.vhost_ops; 67 68 memset(&backend, 0, sizeof(backend)); 69 pstrcpy(backend.vhost_wwpn, sizeof(backend.vhost_wwpn), vs->conf.wwpn); 70 vhost_ops->vhost_scsi_clear_endpoint(&vsc->dev, &backend); 71} 72 73static int vhost_scsi_start(VHostSCSI *s) 74{ 75 int ret, abi_version; 76 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); 77 const VhostOps *vhost_ops = vsc->dev.vhost_ops; 78 79 ret = vhost_ops->vhost_scsi_get_abi_version(&vsc->dev, &abi_version); 80 if (ret < 0) { 81 return -errno; 82 } 83 if (abi_version > VHOST_SCSI_ABI_VERSION) { 84 error_report("vhost-scsi: The running tcm_vhost kernel abi_version:" 85 " %d is greater than vhost_scsi userspace supports: %d," 86 " please upgrade your version of QEMU", abi_version, 87 VHOST_SCSI_ABI_VERSION); 88 return -ENOSYS; 89 } 90 91 ret = vhost_scsi_common_start(vsc); 92 if (ret < 0) { 93 return ret; 94 } 95 96 ret = vhost_scsi_set_endpoint(s); 97 if (ret < 0) { 98 error_report("Error setting vhost-scsi endpoint"); 99 vhost_scsi_common_stop(vsc); 100 } 101 102 return ret; 103} 104 105static void vhost_scsi_stop(VHostSCSI *s) 106{ 107 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); 108 109 vhost_scsi_clear_endpoint(s); 110 vhost_scsi_common_stop(vsc); 111} 112 113static void vhost_scsi_set_status(VirtIODevice *vdev, uint8_t val) 114{ 115 VHostSCSI *s = VHOST_SCSI(vdev); 116 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(s); 117 bool start = (val & VIRTIO_CONFIG_S_DRIVER_OK); 118 119 if (!vdev->vm_running) { 120 start = false; 121 } 122 123 if (vsc->dev.started == start) { 124 return; 125 } 126 127 if (start) { 128 int ret; 129 130 ret = vhost_scsi_start(s); 131 if (ret < 0) { 132 error_report("unable to start vhost-scsi: %s", strerror(-ret)); 133 exit(1); 134 } 135 } else { 136 vhost_scsi_stop(s); 137 } 138} 139 140static void vhost_dummy_handle_output(VirtIODevice *vdev, VirtQueue *vq) 141{ 142} 143 144static int vhost_scsi_pre_save(void *opaque) 145{ 146 VHostSCSICommon *vsc = opaque; 147 148 /* At this point, backend must be stopped, otherwise 149 * it might keep writing to memory. */ 150 assert(!vsc->dev.started); 151 152 return 0; 153} 154 155static const VMStateDescription vmstate_virtio_vhost_scsi = { 156 .name = "virtio-vhost_scsi", 157 .minimum_version_id = 1, 158 .version_id = 1, 159 .fields = (VMStateField[]) { 160 VMSTATE_VIRTIO_DEVICE, 161 VMSTATE_END_OF_LIST() 162 }, 163 .pre_save = vhost_scsi_pre_save, 164}; 165 166static void vhost_scsi_realize(DeviceState *dev, Error **errp) 167{ 168 VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); 169 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(dev); 170 Error *err = NULL; 171 int vhostfd = -1; 172 int ret; 173 174 if (!vs->conf.wwpn) { 175 error_setg(errp, "vhost-scsi: missing wwpn"); 176 return; 177 } 178 179 if (vs->conf.vhostfd) { 180 vhostfd = monitor_fd_param(monitor_cur(), vs->conf.vhostfd, errp); 181 if (vhostfd == -1) { 182 error_prepend(errp, "vhost-scsi: unable to parse vhostfd: "); 183 return; 184 } 185 } else { 186 vhostfd = open("/dev/vhost-scsi", O_RDWR); 187 if (vhostfd < 0) { 188 error_setg(errp, "vhost-scsi: open vhost char device failed: %s", 189 strerror(errno)); 190 return; 191 } 192 } 193 194 virtio_scsi_common_realize(dev, 195 vhost_dummy_handle_output, 196 vhost_dummy_handle_output, 197 vhost_dummy_handle_output, 198 &err); 199 if (err != NULL) { 200 error_propagate(errp, err); 201 goto close_fd; 202 } 203 204 if (!vsc->migratable) { 205 error_setg(&vsc->migration_blocker, 206 "vhost-scsi does not support migration in all cases. " 207 "When external environment supports it (Orchestrator migrates " 208 "target SCSI device state or use shared storage over network), " 209 "set 'migratable' property to true to enable migration."); 210 if (migrate_add_blocker(vsc->migration_blocker, errp) < 0) { 211 goto free_virtio; 212 } 213 } 214 215 vsc->dev.nvqs = VHOST_SCSI_VQ_NUM_FIXED + vs->conf.num_queues; 216 vsc->dev.vqs = g_new0(struct vhost_virtqueue, vsc->dev.nvqs); 217 vsc->dev.vq_index = 0; 218 vsc->dev.backend_features = 0; 219 220 ret = vhost_dev_init(&vsc->dev, (void *)(uintptr_t)vhostfd, 221 VHOST_BACKEND_TYPE_KERNEL, 0, errp); 222 if (ret < 0) { 223 goto free_vqs; 224 } 225 226 /* At present, channel and lun both are 0 for bootable vhost-scsi disk */ 227 vsc->channel = 0; 228 vsc->lun = 0; 229 /* Note: we can also get the minimum tpgt from kernel */ 230 vsc->target = vs->conf.boot_tpgt; 231 232 return; 233 234 free_vqs: 235 g_free(vsc->dev.vqs); 236 if (!vsc->migratable) { 237 migrate_del_blocker(vsc->migration_blocker); 238 } 239 free_virtio: 240 error_free(vsc->migration_blocker); 241 virtio_scsi_common_unrealize(dev); 242 close_fd: 243 close(vhostfd); 244 return; 245} 246 247static void vhost_scsi_unrealize(DeviceState *dev) 248{ 249 VirtIODevice *vdev = VIRTIO_DEVICE(dev); 250 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(dev); 251 struct vhost_virtqueue *vqs = vsc->dev.vqs; 252 253 if (!vsc->migratable) { 254 migrate_del_blocker(vsc->migration_blocker); 255 error_free(vsc->migration_blocker); 256 } 257 258 /* This will stop vhost backend. */ 259 vhost_scsi_set_status(vdev, 0); 260 261 vhost_dev_cleanup(&vsc->dev); 262 g_free(vqs); 263 264 virtio_scsi_common_unrealize(dev); 265} 266 267static Property vhost_scsi_properties[] = { 268 DEFINE_PROP_STRING("vhostfd", VirtIOSCSICommon, conf.vhostfd), 269 DEFINE_PROP_STRING("wwpn", VirtIOSCSICommon, conf.wwpn), 270 DEFINE_PROP_UINT32("boot_tpgt", VirtIOSCSICommon, conf.boot_tpgt, 0), 271 DEFINE_PROP_UINT32("num_queues", VirtIOSCSICommon, conf.num_queues, 272 VIRTIO_SCSI_AUTO_NUM_QUEUES), 273 DEFINE_PROP_UINT32("virtqueue_size", VirtIOSCSICommon, conf.virtqueue_size, 274 128), 275 DEFINE_PROP_BOOL("seg_max_adjust", VirtIOSCSICommon, conf.seg_max_adjust, 276 true), 277 DEFINE_PROP_UINT32("max_sectors", VirtIOSCSICommon, conf.max_sectors, 278 0xFFFF), 279 DEFINE_PROP_UINT32("cmd_per_lun", VirtIOSCSICommon, conf.cmd_per_lun, 128), 280 DEFINE_PROP_BIT64("t10_pi", VHostSCSICommon, host_features, 281 VIRTIO_SCSI_F_T10_PI, 282 false), 283 DEFINE_PROP_BOOL("migratable", VHostSCSICommon, migratable, false), 284 DEFINE_PROP_END_OF_LIST(), 285}; 286 287static void vhost_scsi_class_init(ObjectClass *klass, void *data) 288{ 289 DeviceClass *dc = DEVICE_CLASS(klass); 290 VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass); 291 FWPathProviderClass *fwc = FW_PATH_PROVIDER_CLASS(klass); 292 293 device_class_set_props(dc, vhost_scsi_properties); 294 dc->vmsd = &vmstate_virtio_vhost_scsi; 295 set_bit(DEVICE_CATEGORY_STORAGE, dc->categories); 296 vdc->realize = vhost_scsi_realize; 297 vdc->unrealize = vhost_scsi_unrealize; 298 vdc->get_features = vhost_scsi_common_get_features; 299 vdc->set_config = vhost_scsi_common_set_config; 300 vdc->set_status = vhost_scsi_set_status; 301 fwc->get_dev_path = vhost_scsi_common_get_fw_dev_path; 302} 303 304static void vhost_scsi_instance_init(Object *obj) 305{ 306 VHostSCSICommon *vsc = VHOST_SCSI_COMMON(obj); 307 308 vsc->feature_bits = kernel_feature_bits; 309 310 device_add_bootindex_property(obj, &vsc->bootindex, "bootindex", NULL, 311 DEVICE(vsc)); 312} 313 314static const TypeInfo vhost_scsi_info = { 315 .name = TYPE_VHOST_SCSI, 316 .parent = TYPE_VHOST_SCSI_COMMON, 317 .instance_size = sizeof(VHostSCSI), 318 .class_init = vhost_scsi_class_init, 319 .instance_init = vhost_scsi_instance_init, 320 .interfaces = (InterfaceInfo[]) { 321 { TYPE_FW_PATH_PROVIDER }, 322 { } 323 }, 324}; 325 326static void virtio_register_types(void) 327{ 328 type_register_static(&vhost_scsi_info); 329} 330 331type_init(virtio_register_types)