hw/vfio/ccw.c

   1 /*
   2  * vfio based subchannel assignment support
   3  *
   4  * Copyright 2017 IBM Corp.
   5  * Copyright 2019 Red Hat, Inc.
   6  *
   7  * Author(s): Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
   8  *            Xiao Feng Ren <renxiaof@linux.vnet.ibm.com>
   9  *            Pierre Morel <pmorel@linux.vnet.ibm.com>
  10  *            Cornelia Huck <cohuck@redhat.com>
  11  *
  12  * This work is licensed under the terms of the GNU GPL, version 2 or (at
  13  * your option) any later version. See the COPYING file in the top-level
  14  * directory.
  15  */
  16
  17 #include "qemu/osdep.h"
  18 #include <linux/vfio.h>
  19 #include <linux/vfio_ccw.h>
  20 #include <sys/ioctl.h>
  21
  22 #include "qapi/error.h"
  23 #include "hw/sysbus.h"
  24 #include "hw/vfio/vfio.h"
  25 #include "hw/vfio/vfio-common.h"
  26 #include "hw/s390x/s390-ccw.h"
  27 #include "hw/s390x/vfio-ccw.h"
  28 #include "hw/qdev-properties.h"
  29 #include "hw/s390x/ccw-device.h"
  30 #include "exec/address-spaces.h"
  31 #include "qemu/error-report.h"
  32 #include "qemu/main-loop.h"
  33 #include "qemu/module.h"
  34
  35 struct VFIOCCWDevice {
  36     S390CCWDevice cdev;
  37     VFIODevice vdev;
  38     uint64_t io_region_size;
  39     uint64_t io_region_offset;
  40     struct ccw_io_region *io_region;
  41     uint64_t async_cmd_region_size;
  42     uint64_t async_cmd_region_offset;
  43     struct ccw_cmd_region *async_cmd_region;
  44     uint64_t schib_region_size;
  45     uint64_t schib_region_offset;
  46     struct ccw_schib_region *schib_region;
  47     uint64_t crw_region_size;
  48     uint64_t crw_region_offset;
  49     struct ccw_crw_region *crw_region;
  50     EventNotifier io_notifier;
  51     EventNotifier crw_notifier;
  52     EventNotifier req_notifier;
  53     bool force_orb_pfch;
  54     bool warned_orb_pfch;
  55 };
  56
  57 static inline void warn_once_pfch(VFIOCCWDevice *vcdev, SubchDev *sch,
  58                                   const char *msg)
  59 {
  60     warn_report_once_cond(&vcdev->warned_orb_pfch,
  61                           "vfio-ccw (devno %x.%x.%04x): %s",
  62                           sch->cssid, sch->ssid, sch->devno, msg);
  63 }
  64
  65 static void vfio_ccw_compute_needs_reset(VFIODevice *vdev)
  66 {
  67     vdev->needs_reset = false;
  68 }
  69
  70 /*
  71  * We don't need vfio_hot_reset_multi and vfio_eoi operations for
  72  * vfio_ccw device now.
  73  */
  74 struct VFIODeviceOps vfio_ccw_ops = {
  75     .vfio_compute_needs_reset = vfio_ccw_compute_needs_reset,
  76 };
  77
  78 static IOInstEnding vfio_ccw_handle_request(SubchDev *sch)
  79 {
  80     S390CCWDevice *cdev = sch->driver_data;
  81     VFIOCCWDevice *vcdev = DO_UPCAST(VFIOCCWDevice, cdev, cdev);
  82     struct ccw_io_region *region = vcdev->io_region;
  83     int ret;
  84
  85     if (!(sch->orb.ctrl0 & ORB_CTRL0_MASK_PFCH) && vcdev->force_orb_pfch) {
  86         sch->orb.ctrl0 |= ORB_CTRL0_MASK_PFCH;
  87         warn_once_pfch(vcdev, sch, "PFCH flag forced");
  88     }
  89
  90     QEMU_BUILD_BUG_ON(sizeof(region->orb_area) != sizeof(ORB));
  91     QEMU_BUILD_BUG_ON(sizeof(region->scsw_area) != sizeof(SCSW));
  92     QEMU_BUILD_BUG_ON(sizeof(region->irb_area) != sizeof(IRB));
  93
  94     memset(region, 0, sizeof(*region));
  95
  96     memcpy(region->orb_area, &sch->orb, sizeof(ORB));
  97     memcpy(region->scsw_area, &sch->curr_status.scsw, sizeof(SCSW));
  98
  99 again:
 100     ret = pwrite(vcdev->vdev.fd, region,
 101                  vcdev->io_region_size, vcdev->io_region_offset);
 102     if (ret != vcdev->io_region_size) {
 103         if (errno == EAGAIN) {
 104             goto again;
 105         }
 106         error_report("vfio-ccw: write I/O region failed with errno=%d", errno);
 107         ret = errno ? -errno : -EFAULT;
 108     } else {
 109         ret = 0;
 110     }
 111     switch (ret) {
 112     case 0:
 113         return IOINST_CC_EXPECTED;
 114     case -EBUSY:
 115         return IOINST_CC_BUSY;
 116     case -ENODEV:
 117     case -EACCES:
 118         return IOINST_CC_NOT_OPERATIONAL;
 119     case -EFAULT:
 120     default:
 121         sch_gen_unit_exception(sch);
 122         css_inject_io_interrupt(sch);
 123         return IOINST_CC_EXPECTED;
 124     }
 125 }
 126
 127 static IOInstEnding vfio_ccw_handle_store(SubchDev *sch)
 128 {
 129     S390CCWDevice *cdev = sch->driver_data;
 130     VFIOCCWDevice *vcdev = DO_UPCAST(VFIOCCWDevice, cdev, cdev);
 131     SCHIB *schib = &sch->curr_status;
 132     struct ccw_schib_region *region = vcdev->schib_region;
 133     SCHIB *s;
 134     int ret;
 135
 136     /* schib region not available so nothing else to do */
 137     if (!region) {
 138         return IOINST_CC_EXPECTED;
 139     }
 140
 141     memset(region, 0, sizeof(*region));
 142     ret = pread(vcdev->vdev.fd, region, vcdev->schib_region_size,
 143                 vcdev->schib_region_offset);
 144
 145     if (ret == -1) {
 146         /*
 147          * Device is probably damaged, but store subchannel does not
 148          * have a nonzero cc defined for this scenario.  Log an error,
 149          * and presume things are otherwise fine.
 150          */
 151         error_report("vfio-ccw: store region read failed with errno=%d", errno);
 152         return IOINST_CC_EXPECTED;
 153     }
 154
 155     /*
 156      * Selectively copy path-related bits of the SCHIB,
 157      * rather than copying the entire struct.
 158      */
 159     s = (SCHIB *)region->schib_area;
 160     schib->pmcw.pnom = s->pmcw.pnom;
 161     schib->pmcw.lpum = s->pmcw.lpum;
 162     schib->pmcw.pam = s->pmcw.pam;
 163     schib->pmcw.pom = s->pmcw.pom;
 164
 165     if (s->scsw.flags & SCSW_FLAGS_MASK_PNO) {
 166         schib->scsw.flags |= SCSW_FLAGS_MASK_PNO;
 167     }
 168
 169     return IOINST_CC_EXPECTED;
 170 }
 171
 172 static int vfio_ccw_handle_clear(SubchDev *sch)
 173 {
 174     S390CCWDevice *cdev = sch->driver_data;
 175     VFIOCCWDevice *vcdev = DO_UPCAST(VFIOCCWDevice, cdev, cdev);
 176     struct ccw_cmd_region *region = vcdev->async_cmd_region;
 177     int ret;
 178
 179     if (!vcdev->async_cmd_region) {
 180         /* Async command region not available, fall back to emulation */
 181         return -ENOSYS;
 182     }
 183
 184     memset(region, 0, sizeof(*region));
 185     region->command = VFIO_CCW_ASYNC_CMD_CSCH;
 186
 187 again:
 188     ret = pwrite(vcdev->vdev.fd, region,
 189                  vcdev->async_cmd_region_size, vcdev->async_cmd_region_offset);
 190     if (ret != vcdev->async_cmd_region_size) {
 191         if (errno == EAGAIN) {
 192             goto again;
 193         }
 194         error_report("vfio-ccw: write cmd region failed with errno=%d", errno);
 195         ret = errno ? -errno : -EFAULT;
 196     } else {
 197         ret = 0;
 198     }
 199     switch (ret) {
 200     case 0:
 201     case -ENODEV:
 202     case -EACCES:
 203         return 0;
 204     case -EFAULT:
 205     default:
 206         sch_gen_unit_exception(sch);
 207         css_inject_io_interrupt(sch);
 208         return 0;
 209     }
 210 }
 211
 212 static int vfio_ccw_handle_halt(SubchDev *sch)
 213 {
 214     S390CCWDevice *cdev = sch->driver_data;
 215     VFIOCCWDevice *vcdev = DO_UPCAST(VFIOCCWDevice, cdev, cdev);
 216     struct ccw_cmd_region *region = vcdev->async_cmd_region;
 217     int ret;
 218
 219     if (!vcdev->async_cmd_region) {
 220         /* Async command region not available, fall back to emulation */
 221         return -ENOSYS;
 222     }
 223
 224     memset(region, 0, sizeof(*region));
 225     region->command = VFIO_CCW_ASYNC_CMD_HSCH;
 226
 227 again:
 228     ret = pwrite(vcdev->vdev.fd, region,
 229                  vcdev->async_cmd_region_size, vcdev->async_cmd_region_offset);
 230     if (ret != vcdev->async_cmd_region_size) {
 231         if (errno == EAGAIN) {
 232             goto again;
 233         }
 234         error_report("vfio-ccw: write cmd region failed with errno=%d", errno);
 235         ret = errno ? -errno : -EFAULT;
 236     } else {
 237         ret = 0;
 238     }
 239     switch (ret) {
 240     case 0:
 241     case -EBUSY:
 242     case -ENODEV:
 243     case -EACCES:
 244         return 0;
 245     case -EFAULT:
 246     default:
 247         sch_gen_unit_exception(sch);
 248         css_inject_io_interrupt(sch);
 249         return 0;
 250     }
 251 }
 252
 253 static void vfio_ccw_reset(DeviceState *dev)
 254 {
 255     CcwDevice *ccw_dev = DO_UPCAST(CcwDevice, parent_obj, dev);
 256     S390CCWDevice *cdev = DO_UPCAST(S390CCWDevice, parent_obj, ccw_dev);
 257     VFIOCCWDevice *vcdev = DO_UPCAST(VFIOCCWDevice, cdev, cdev);
 258
 259     ioctl(vcdev->vdev.fd, VFIO_DEVICE_RESET);
 260 }
 261
 262 static void vfio_ccw_crw_read(VFIOCCWDevice *vcdev)
 263 {
 264     struct ccw_crw_region *region = vcdev->crw_region;
 265     CRW crw;
 266     int size;
 267
 268     /* Keep reading CRWs as long as data is returned */
 269     do {
 270         memset(region, 0, sizeof(*region));
 271         size = pread(vcdev->vdev.fd, region, vcdev->crw_region_size,
 272                      vcdev->crw_region_offset);
 273
 274         if (size == -1) {
 275             error_report("vfio-ccw: Read crw region failed with errno=%d",
 276                          errno);
 277             break;
 278         }
 279
 280         if (region->crw == 0) {
 281             /* No more CRWs to queue */
 282             break;
 283         }
 284
 285         memcpy(&crw, &region->crw, sizeof(CRW));
 286
 287         css_crw_add_to_queue(crw);
 288     } while (1);
 289 }
 290
 291 static void vfio_ccw_req_notifier_handler(void *opaque)
 292 {
 293     VFIOCCWDevice *vcdev = opaque;
 294     Error *err = NULL;
 295
 296     if (!event_notifier_test_and_clear(&vcdev->req_notifier)) {
 297         return;
 298     }
 299
 300     qdev_unplug(DEVICE(vcdev), &err);
 301     if (err) {
 302         warn_reportf_err(err, VFIO_MSG_PREFIX, vcdev->vdev.name);
 303     }
 304 }
 305
 306 static void vfio_ccw_crw_notifier_handler(void *opaque)
 307 {
 308     VFIOCCWDevice *vcdev = opaque;
 309
 310     while (event_notifier_test_and_clear(&vcdev->crw_notifier)) {
 311         vfio_ccw_crw_read(vcdev);
 312     }
 313 }
 314
 315 static void vfio_ccw_io_notifier_handler(void *opaque)
 316 {
 317     VFIOCCWDevice *vcdev = opaque;
 318     struct ccw_io_region *region = vcdev->io_region;
 319     S390CCWDevice *cdev = S390_CCW_DEVICE(vcdev);
 320     CcwDevice *ccw_dev = CCW_DEVICE(cdev);
 321     SubchDev *sch = ccw_dev->sch;
 322     SCHIB *schib = &sch->curr_status;
 323     SCSW s;
 324     IRB irb;
 325     int size;
 326
 327     if (!event_notifier_test_and_clear(&vcdev->io_notifier)) {
 328         return;
 329     }
 330
 331     size = pread(vcdev->vdev.fd, region, vcdev->io_region_size,
 332                  vcdev->io_region_offset);
 333     if (size == -1) {
 334         switch (errno) {
 335         case ENODEV:
 336             /* Generate a deferred cc 3 condition. */
 337             schib->scsw.flags |= SCSW_FLAGS_MASK_CC;
 338             schib->scsw.ctrl &= ~SCSW_CTRL_MASK_STCTL;
 339             schib->scsw.ctrl |= (SCSW_STCTL_ALERT | SCSW_STCTL_STATUS_PEND);
 340             goto read_err;
 341         case EFAULT:
 342             /* Memory problem, generate channel data check. */
 343             schib->scsw.ctrl &= ~SCSW_ACTL_START_PEND;
 344             schib->scsw.cstat = SCSW_CSTAT_DATA_CHECK;
 345             schib->scsw.ctrl &= ~SCSW_CTRL_MASK_STCTL;
 346             schib->scsw.ctrl |= SCSW_STCTL_PRIMARY | SCSW_STCTL_SECONDARY |
 347                        SCSW_STCTL_ALERT | SCSW_STCTL_STATUS_PEND;
 348             goto read_err;
 349         default:
 350             /* Error, generate channel program check. */
 351             schib->scsw.ctrl &= ~SCSW_ACTL_START_PEND;
 352             schib->scsw.cstat = SCSW_CSTAT_PROG_CHECK;
 353             schib->scsw.ctrl &= ~SCSW_CTRL_MASK_STCTL;
 354             schib->scsw.ctrl |= SCSW_STCTL_PRIMARY | SCSW_STCTL_SECONDARY |
 355                        SCSW_STCTL_ALERT | SCSW_STCTL_STATUS_PEND;
 356             goto read_err;
 357         }
 358     } else if (size != vcdev->io_region_size) {
 359         /* Information transfer error, generate channel-control check. */
 360         schib->scsw.ctrl &= ~SCSW_ACTL_START_PEND;
 361         schib->scsw.cstat = SCSW_CSTAT_CHN_CTRL_CHK;
 362         schib->scsw.ctrl &= ~SCSW_CTRL_MASK_STCTL;
 363         schib->scsw.ctrl |= SCSW_STCTL_PRIMARY | SCSW_STCTL_SECONDARY |
 364                    SCSW_STCTL_ALERT | SCSW_STCTL_STATUS_PEND;
 365         goto read_err;
 366     }
 367
 368     memcpy(&irb, region->irb_area, sizeof(IRB));
 369
 370     /* Update control block via irb. */
 371     s = schib->scsw;
 372     copy_scsw_to_guest(&s, &irb.scsw);
 373     schib->scsw = s;
 374
 375     /* If a uint check is pending, copy sense data. */
 376     if ((schib->scsw.dstat & SCSW_DSTAT_UNIT_CHECK) &&
 377         (schib->pmcw.chars & PMCW_CHARS_MASK_CSENSE)) {
 378         memcpy(sch->sense_data, irb.ecw, sizeof(irb.ecw));
 379     }
 380
 381 read_err:
 382     css_inject_io_interrupt(sch);
 383 }
 384
 385 static void vfio_ccw_register_irq_notifier(VFIOCCWDevice *vcdev,
 386                                            unsigned int irq,
 387                                            Error **errp)
 388 {
 389     VFIODevice *vdev = &vcdev->vdev;
 390     struct vfio_irq_info *irq_info;
 391     size_t argsz;
 392     int fd;
 393     EventNotifier *notifier;
 394     IOHandler *fd_read;
 395
 396     switch (irq) {
 397     case VFIO_CCW_IO_IRQ_INDEX:
 398         notifier = &vcdev->io_notifier;
 399         fd_read = vfio_ccw_io_notifier_handler;
 400         break;
 401     case VFIO_CCW_CRW_IRQ_INDEX:
 402         notifier = &vcdev->crw_notifier;
 403         fd_read = vfio_ccw_crw_notifier_handler;
 404         break;
 405     case VFIO_CCW_REQ_IRQ_INDEX:
 406         notifier = &vcdev->req_notifier;
 407         fd_read = vfio_ccw_req_notifier_handler;
 408         break;
 409     default:
 410         error_setg(errp, "vfio: Unsupported device irq(%d)", irq);
 411         return;
 412     }
 413
 414     if (vdev->num_irqs < irq + 1) {
 415         error_setg(errp, "vfio: unexpected number of irqs %u",
 416                    vdev->num_irqs);
 417         return;
 418     }
 419
 420     argsz = sizeof(*irq_info);
 421     irq_info = g_malloc0(argsz);
 422     irq_info->index = irq;
 423     irq_info->argsz = argsz;
 424     if (ioctl(vdev->fd, VFIO_DEVICE_GET_IRQ_INFO,
 425               irq_info) < 0 || irq_info->count < 1) {
 426         error_setg_errno(errp, errno, "vfio: Error getting irq info");
 427         goto out_free_info;
 428     }
 429
 430     if (event_notifier_init(notifier, 0)) {
 431         error_setg_errno(errp, errno,
 432                          "vfio: Unable to init event notifier for irq (%d)",
 433                          irq);
 434         goto out_free_info;
 435     }
 436
 437     fd = event_notifier_get_fd(notifier);
 438     qemu_set_fd_handler(fd, fd_read, NULL, vcdev);
 439
 440     if (vfio_set_irq_signaling(vdev, irq, 0,
 441                                VFIO_IRQ_SET_ACTION_TRIGGER, fd, errp)) {
 442         qemu_set_fd_handler(fd, NULL, NULL, vcdev);
 443         event_notifier_cleanup(notifier);
 444     }
 445
 446 out_free_info:
 447     g_free(irq_info);
 448 }
 449
 450 static void vfio_ccw_unregister_irq_notifier(VFIOCCWDevice *vcdev,
 451                                              unsigned int irq)
 452 {
 453     Error *err = NULL;
 454     EventNotifier *notifier;
 455
 456     switch (irq) {
 457     case VFIO_CCW_IO_IRQ_INDEX:
 458         notifier = &vcdev->io_notifier;
 459         break;
 460     case VFIO_CCW_CRW_IRQ_INDEX:
 461         notifier = &vcdev->crw_notifier;
 462         break;
 463     case VFIO_CCW_REQ_IRQ_INDEX:
 464         notifier = &vcdev->req_notifier;
 465         break;
 466     default:
 467         error_report("vfio: Unsupported device irq(%d)", irq);
 468         return;
 469     }
 470
 471     if (vfio_set_irq_signaling(&vcdev->vdev, irq, 0,
 472                                VFIO_IRQ_SET_ACTION_TRIGGER, -1, &err)) {
 473         error_reportf_err(err, VFIO_MSG_PREFIX, vcdev->vdev.name);
 474     }
 475
 476     qemu_set_fd_handler(event_notifier_get_fd(notifier),
 477                         NULL, NULL, vcdev);
 478     event_notifier_cleanup(notifier);
 479 }
 480
 481 static void vfio_ccw_get_region(VFIOCCWDevice *vcdev, Error **errp)
 482 {
 483     VFIODevice *vdev = &vcdev->vdev;
 484     struct vfio_region_info *info;
 485     int ret;
 486
 487     /* Sanity check device */
 488     if (!(vdev->flags & VFIO_DEVICE_FLAGS_CCW)) {
 489         error_setg(errp, "vfio: Um, this isn't a vfio-ccw device");
 490         return;
 491     }
 492
 493     /*
 494      * We always expect at least the I/O region to be present. We also
 495      * may have a variable number of regions governed by capabilities.
 496      */
 497     if (vdev->num_regions < VFIO_CCW_CONFIG_REGION_INDEX + 1) {
 498         error_setg(errp, "vfio: too few regions (%u), expected at least %u",
 499                    vdev->num_regions, VFIO_CCW_CONFIG_REGION_INDEX + 1);
 500         return;
 501     }
 502
 503     ret = vfio_get_region_info(vdev, VFIO_CCW_CONFIG_REGION_INDEX, &info);
 504     if (ret) {
 505         error_setg_errno(errp, -ret, "vfio: Error getting config info");
 506         return;
 507     }
 508
 509     vcdev->io_region_size = info->size;
 510     if (sizeof(*vcdev->io_region) != vcdev->io_region_size) {
 511         error_setg(errp, "vfio: Unexpected size of the I/O region");
 512         goto out_err;
 513     }
 514
 515     vcdev->io_region_offset = info->offset;
 516     vcdev->io_region = g_malloc0(info->size);
 517     g_free(info);
 518
 519     /* check for the optional async command region */
 520     ret = vfio_get_dev_region_info(vdev, VFIO_REGION_TYPE_CCW,
 521                                    VFIO_REGION_SUBTYPE_CCW_ASYNC_CMD, &info);
 522     if (!ret) {
 523         vcdev->async_cmd_region_size = info->size;
 524         if (sizeof(*vcdev->async_cmd_region) != vcdev->async_cmd_region_size) {
 525             error_setg(errp, "vfio: Unexpected size of the async cmd region");
 526             goto out_err;
 527         }
 528         vcdev->async_cmd_region_offset = info->offset;
 529         vcdev->async_cmd_region = g_malloc0(info->size);
 530         g_free(info);
 531     }
 532
 533     ret = vfio_get_dev_region_info(vdev, VFIO_REGION_TYPE_CCW,
 534                                    VFIO_REGION_SUBTYPE_CCW_SCHIB, &info);
 535     if (!ret) {
 536         vcdev->schib_region_size = info->size;
 537         if (sizeof(*vcdev->schib_region) != vcdev->schib_region_size) {
 538             error_setg(errp, "vfio: Unexpected size of the schib region");
 539             goto out_err;
 540         }
 541         vcdev->schib_region_offset = info->offset;
 542         vcdev->schib_region = g_malloc(info->size);
 543         g_free(info);
 544     }
 545
 546     ret = vfio_get_dev_region_info(vdev, VFIO_REGION_TYPE_CCW,
 547                                    VFIO_REGION_SUBTYPE_CCW_CRW, &info);
 548
 549     if (!ret) {
 550         vcdev->crw_region_size = info->size;
 551         if (sizeof(*vcdev->crw_region) != vcdev->crw_region_size) {
 552             error_setg(errp, "vfio: Unexpected size of the CRW region");
 553             goto out_err;
 554         }
 555         vcdev->crw_region_offset = info->offset;
 556         vcdev->crw_region = g_malloc(info->size);
 557         g_free(info);
 558     }
 559
 560     return;
 561
 562 out_err:
 563     g_free(vcdev->crw_region);
 564     g_free(vcdev->schib_region);
 565     g_free(vcdev->async_cmd_region);
 566     g_free(vcdev->io_region);
 567     g_free(info);
 568     return;
 569 }
 570
 571 static void vfio_ccw_put_region(VFIOCCWDevice *vcdev)
 572 {
 573     g_free(vcdev->crw_region);
 574     g_free(vcdev->schib_region);
 575     g_free(vcdev->async_cmd_region);
 576     g_free(vcdev->io_region);
 577 }
 578
 579 static void vfio_ccw_put_device(VFIOCCWDevice *vcdev)
 580 {
 581     g_free(vcdev->vdev.name);
 582     vfio_put_base_device(&vcdev->vdev);
 583 }
 584
 585 static void vfio_ccw_get_device(VFIOGroup *group, VFIOCCWDevice *vcdev,
 586                                 Error **errp)
 587 {
 588     char *name = g_strdup_printf("%x.%x.%04x", vcdev->cdev.hostid.cssid,
 589                                  vcdev->cdev.hostid.ssid,
 590                                  vcdev->cdev.hostid.devid);
 591     VFIODevice *vbasedev;
 592
 593     QLIST_FOREACH(vbasedev, &group->device_list, next) {
 594         if (strcmp(vbasedev->name, name) == 0) {
 595             error_setg(errp, "vfio: subchannel %s has already been attached",
 596                        name);
 597             goto out_err;
 598         }
 599     }
 600
 601     /*
 602      * All vfio-ccw devices are believed to operate in a way compatible with
 603      * discarding of memory in RAM blocks, ie. pages pinned in the host are
 604      * in the current working set of the guest driver and therefore never
 605      * overlap e.g., with pages available to the guest balloon driver.  This
 606      * needs to be set before vfio_get_device() for vfio common to handle
 607      * ram_block_discard_disable().
 608      */
 609     vcdev->vdev.ram_block_discard_allowed = true;
 610
 611     if (vfio_get_device(group, vcdev->cdev.mdevid, &vcdev->vdev, errp)) {
 612         goto out_err;
 613     }
 614
 615     vcdev->vdev.ops = &vfio_ccw_ops;
 616     vcdev->vdev.type = VFIO_DEVICE_TYPE_CCW;
 617     vcdev->vdev.name = name;
 618     vcdev->vdev.dev = &vcdev->cdev.parent_obj.parent_obj;
 619
 620     return;
 621
 622 out_err:
 623     g_free(name);
 624 }
 625
 626 static VFIOGroup *vfio_ccw_get_group(S390CCWDevice *cdev, Error **errp)
 627 {
 628     char *tmp, group_path[PATH_MAX];
 629     ssize_t len;
 630     int groupid;
 631
 632     tmp = g_strdup_printf("/sys/bus/css/devices/%x.%x.%04x/%s/iommu_group",
 633                           cdev->hostid.cssid, cdev->hostid.ssid,
 634                           cdev->hostid.devid, cdev->mdevid);
 635     len = readlink(tmp, group_path, sizeof(group_path));
 636     g_free(tmp);
 637
 638     if (len <= 0 || len >= sizeof(group_path)) {
 639         error_setg(errp, "vfio: no iommu_group found");
 640         return NULL;
 641     }
 642
 643     group_path[len] = 0;
 644
 645     if (sscanf(basename(group_path), "%d", &groupid) != 1) {
 646         error_setg(errp, "vfio: failed to read %s", group_path);
 647         return NULL;
 648     }
 649
 650     return vfio_get_group(groupid, &address_space_memory, errp);
 651 }
 652
 653 static void vfio_ccw_realize(DeviceState *dev, Error **errp)
 654 {
 655     VFIOGroup *group;
 656     CcwDevice *ccw_dev = DO_UPCAST(CcwDevice, parent_obj, dev);
 657     S390CCWDevice *cdev = DO_UPCAST(S390CCWDevice, parent_obj, ccw_dev);
 658     VFIOCCWDevice *vcdev = DO_UPCAST(VFIOCCWDevice, cdev, cdev);
 659     S390CCWDeviceClass *cdc = S390_CCW_DEVICE_GET_CLASS(cdev);
 660     Error *err = NULL;
 661
 662     /* Call the class init function for subchannel. */
 663     if (cdc->realize) {
 664         cdc->realize(cdev, vcdev->vdev.sysfsdev, &err);
 665         if (err) {
 666             goto out_err_propagate;
 667         }
 668     }
 669
 670     group = vfio_ccw_get_group(cdev, &err);
 671     if (!group) {
 672         goto out_group_err;
 673     }
 674
 675     vfio_ccw_get_device(group, vcdev, &err);
 676     if (err) {
 677         goto out_device_err;
 678     }
 679
 680     vfio_ccw_get_region(vcdev, &err);
 681     if (err) {
 682         goto out_region_err;
 683     }
 684
 685     vfio_ccw_register_irq_notifier(vcdev, VFIO_CCW_IO_IRQ_INDEX, &err);
 686     if (err) {
 687         goto out_io_notifier_err;
 688     }
 689
 690     if (vcdev->crw_region) {
 691         vfio_ccw_register_irq_notifier(vcdev, VFIO_CCW_CRW_IRQ_INDEX, &err);
 692         if (err) {
 693             goto out_crw_notifier_err;
 694         }
 695     }
 696
 697     vfio_ccw_register_irq_notifier(vcdev, VFIO_CCW_REQ_IRQ_INDEX, &err);
 698     if (err) {
 699         goto out_req_notifier_err;
 700     }
 701
 702     return;
 703
 704 out_req_notifier_err:
 705     vfio_ccw_unregister_irq_notifier(vcdev, VFIO_CCW_CRW_IRQ_INDEX);
 706 out_crw_notifier_err:
 707     vfio_ccw_unregister_irq_notifier(vcdev, VFIO_CCW_IO_IRQ_INDEX);
 708 out_io_notifier_err:
 709     vfio_ccw_put_region(vcdev);
 710 out_region_err:
 711     vfio_ccw_put_device(vcdev);
 712 out_device_err:
 713     vfio_put_group(group);
 714 out_group_err:
 715     if (cdc->unrealize) {
 716         cdc->unrealize(cdev);
 717     }
 718 out_err_propagate:
 719     error_propagate(errp, err);
 720 }
 721
 722 static void vfio_ccw_unrealize(DeviceState *dev)
 723 {
 724     CcwDevice *ccw_dev = DO_UPCAST(CcwDevice, parent_obj, dev);
 725     S390CCWDevice *cdev = DO_UPCAST(S390CCWDevice, parent_obj, ccw_dev);
 726     VFIOCCWDevice *vcdev = DO_UPCAST(VFIOCCWDevice, cdev, cdev);
 727     S390CCWDeviceClass *cdc = S390_CCW_DEVICE_GET_CLASS(cdev);
 728     VFIOGroup *group = vcdev->vdev.group;
 729
 730     vfio_ccw_unregister_irq_notifier(vcdev, VFIO_CCW_REQ_IRQ_INDEX);
 731     vfio_ccw_unregister_irq_notifier(vcdev, VFIO_CCW_CRW_IRQ_INDEX);
 732     vfio_ccw_unregister_irq_notifier(vcdev, VFIO_CCW_IO_IRQ_INDEX);
 733     vfio_ccw_put_region(vcdev);
 734     vfio_ccw_put_device(vcdev);
 735     vfio_put_group(group);
 736
 737     if (cdc->unrealize) {
 738         cdc->unrealize(cdev);
 739     }
 740 }
 741
 742 static Property vfio_ccw_properties[] = {
 743     DEFINE_PROP_STRING("sysfsdev", VFIOCCWDevice, vdev.sysfsdev),
 744     DEFINE_PROP_BOOL("force-orb-pfch", VFIOCCWDevice, force_orb_pfch, false),
 745     DEFINE_PROP_END_OF_LIST(),
 746 };
 747
 748 static const VMStateDescription vfio_ccw_vmstate = {
 749     .name = "vfio-ccw",
 750     .unmigratable = 1,
 751 };
 752
 753 static void vfio_ccw_class_init(ObjectClass *klass, void *data)
 754 {
 755     DeviceClass *dc = DEVICE_CLASS(klass);
 756     S390CCWDeviceClass *cdc = S390_CCW_DEVICE_CLASS(klass);
 757
 758     device_class_set_props(dc, vfio_ccw_properties);
 759     dc->vmsd = &vfio_ccw_vmstate;
 760     dc->desc = "VFIO-based subchannel assignment";
 761     set_bit(DEVICE_CATEGORY_MISC, dc->categories);
 762     dc->realize = vfio_ccw_realize;
 763     dc->unrealize = vfio_ccw_unrealize;
 764     dc->reset = vfio_ccw_reset;
 765
 766     cdc->handle_request = vfio_ccw_handle_request;
 767     cdc->handle_halt = vfio_ccw_handle_halt;
 768     cdc->handle_clear = vfio_ccw_handle_clear;
 769     cdc->handle_store = vfio_ccw_handle_store;
 770 }
 771
 772 static const TypeInfo vfio_ccw_info = {
 773     .name = TYPE_VFIO_CCW,
 774     .parent = TYPE_S390_CCW,
 775     .instance_size = sizeof(VFIOCCWDevice),
 776     .class_init = vfio_ccw_class_init,
 777 };
 778
 779 static void register_vfio_ccw_type(void)
 780 {
 781     type_register_static(&vfio_ccw_info);
 782 }
 783
 784 type_init(register_vfio_ccw_type)