qemu/hw/vfio/ccw.c
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   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/vfio/vfio.h"
  24#include "hw/vfio/vfio-common.h"
  25#include "hw/s390x/s390-ccw.h"
  26#include "hw/s390x/vfio-ccw.h"
  27#include "hw/qdev-properties.h"
  28#include "hw/s390x/ccw-device.h"
  29#include "exec/address-spaces.h"
  30#include "qemu/error-report.h"
  31#include "qemu/main-loop.h"
  32#include "qemu/module.h"
  33
  34struct VFIOCCWDevice {
  35    S390CCWDevice cdev;
  36    VFIODevice vdev;
  37    uint64_t io_region_size;
  38    uint64_t io_region_offset;
  39    struct ccw_io_region *io_region;
  40    uint64_t async_cmd_region_size;
  41    uint64_t async_cmd_region_offset;
  42    struct ccw_cmd_region *async_cmd_region;
  43    uint64_t schib_region_size;
  44    uint64_t schib_region_offset;
  45    struct ccw_schib_region *schib_region;
  46    uint64_t crw_region_size;
  47    uint64_t crw_region_offset;
  48    struct ccw_crw_region *crw_region;
  49    EventNotifier io_notifier;
  50    EventNotifier crw_notifier;
  51    EventNotifier req_notifier;
  52    bool force_orb_pfch;
  53    bool warned_orb_pfch;
  54};
  55
  56static inline void warn_once_pfch(VFIOCCWDevice *vcdev, SubchDev *sch,
  57                                  const char *msg)
  58{
  59    warn_report_once_cond(&vcdev->warned_orb_pfch,
  60                          "vfio-ccw (devno %x.%x.%04x): %s",
  61                          sch->cssid, sch->ssid, sch->devno, msg);
  62}
  63
  64static void vfio_ccw_compute_needs_reset(VFIODevice *vdev)
  65{
  66    vdev->needs_reset = false;
  67}
  68
  69/*
  70 * We don't need vfio_hot_reset_multi and vfio_eoi operations for
  71 * vfio_ccw device now.
  72 */
  73struct VFIODeviceOps vfio_ccw_ops = {
  74    .vfio_compute_needs_reset = vfio_ccw_compute_needs_reset,
  75};
  76
  77static IOInstEnding vfio_ccw_handle_request(SubchDev *sch)
  78{
  79    S390CCWDevice *cdev = sch->driver_data;
  80    VFIOCCWDevice *vcdev = DO_UPCAST(VFIOCCWDevice, cdev, cdev);
  81    struct ccw_io_region *region = vcdev->io_region;
  82    int ret;
  83
  84    if (!(sch->orb.ctrl0 & ORB_CTRL0_MASK_PFCH) && vcdev->force_orb_pfch) {
  85        sch->orb.ctrl0 |= ORB_CTRL0_MASK_PFCH;
  86        warn_once_pfch(vcdev, sch, "PFCH flag forced");
  87    }
  88
  89    QEMU_BUILD_BUG_ON(sizeof(region->orb_area) != sizeof(ORB));
  90    QEMU_BUILD_BUG_ON(sizeof(region->scsw_area) != sizeof(SCSW));
  91    QEMU_BUILD_BUG_ON(sizeof(region->irb_area) != sizeof(IRB));
  92
  93    memset(region, 0, sizeof(*region));
  94
  95    memcpy(region->orb_area, &sch->orb, sizeof(ORB));
  96    memcpy(region->scsw_area, &sch->curr_status.scsw, sizeof(SCSW));
  97
  98again:
  99    ret = pwrite(vcdev->vdev.fd, region,
 100                 vcdev->io_region_size, vcdev->io_region_offset);
 101    if (ret != vcdev->io_region_size) {
 102        if (errno == EAGAIN) {
 103            goto again;
 104        }
 105        error_report("vfio-ccw: write I/O region failed with errno=%d", errno);
 106        ret = errno ? -errno : -EFAULT;
 107    } else {
 108        ret = 0;
 109    }
 110    switch (ret) {
 111    case 0:
 112        return IOINST_CC_EXPECTED;
 113    case -EBUSY:
 114        return IOINST_CC_BUSY;
 115    case -ENODEV:
 116    case -EACCES:
 117        return IOINST_CC_NOT_OPERATIONAL;
 118    case -EFAULT:
 119    default:
 120        sch_gen_unit_exception(sch);
 121        css_inject_io_interrupt(sch);
 122        return IOINST_CC_EXPECTED;
 123    }
 124}
 125
 126static IOInstEnding vfio_ccw_handle_store(SubchDev *sch)
 127{
 128    S390CCWDevice *cdev = sch->driver_data;
 129    VFIOCCWDevice *vcdev = DO_UPCAST(VFIOCCWDevice, cdev, cdev);
 130    SCHIB *schib = &sch->curr_status;
 131    struct ccw_schib_region *region = vcdev->schib_region;
 132    SCHIB *s;
 133    int ret;
 134
 135    /* schib region not available so nothing else to do */
 136    if (!region) {
 137        return IOINST_CC_EXPECTED;
 138    }
 139
 140    memset(region, 0, sizeof(*region));
 141    ret = pread(vcdev->vdev.fd, region, vcdev->schib_region_size,
 142                vcdev->schib_region_offset);
 143
 144    if (ret == -1) {
 145        /*
 146         * Device is probably damaged, but store subchannel does not
 147         * have a nonzero cc defined for this scenario.  Log an error,
 148         * and presume things are otherwise fine.
 149         */
 150        error_report("vfio-ccw: store region read failed with errno=%d", errno);
 151        return IOINST_CC_EXPECTED;
 152    }
 153
 154    /*
 155     * Selectively copy path-related bits of the SCHIB,
 156     * rather than copying the entire struct.
 157     */
 158    s = (SCHIB *)region->schib_area;
 159    schib->pmcw.pnom = s->pmcw.pnom;
 160    schib->pmcw.lpum = s->pmcw.lpum;
 161    schib->pmcw.pam = s->pmcw.pam;
 162    schib->pmcw.pom = s->pmcw.pom;
 163
 164    if (s->scsw.flags & SCSW_FLAGS_MASK_PNO) {
 165        schib->scsw.flags |= SCSW_FLAGS_MASK_PNO;
 166    }
 167
 168    return IOINST_CC_EXPECTED;
 169}
 170
 171static int vfio_ccw_handle_clear(SubchDev *sch)
 172{
 173    S390CCWDevice *cdev = sch->driver_data;
 174    VFIOCCWDevice *vcdev = DO_UPCAST(VFIOCCWDevice, cdev, cdev);
 175    struct ccw_cmd_region *region = vcdev->async_cmd_region;
 176    int ret;
 177
 178    if (!vcdev->async_cmd_region) {
 179        /* Async command region not available, fall back to emulation */
 180        return -ENOSYS;
 181    }
 182
 183    memset(region, 0, sizeof(*region));
 184    region->command = VFIO_CCW_ASYNC_CMD_CSCH;
 185
 186again:
 187    ret = pwrite(vcdev->vdev.fd, region,
 188                 vcdev->async_cmd_region_size, vcdev->async_cmd_region_offset);
 189    if (ret != vcdev->async_cmd_region_size) {
 190        if (errno == EAGAIN) {
 191            goto again;
 192        }
 193        error_report("vfio-ccw: write cmd region failed with errno=%d", errno);
 194        ret = errno ? -errno : -EFAULT;
 195    } else {
 196        ret = 0;
 197    }
 198    switch (ret) {
 199    case 0:
 200    case -ENODEV:
 201    case -EACCES:
 202        return ret;
 203    case -EFAULT:
 204    default:
 205        sch_gen_unit_exception(sch);
 206        css_inject_io_interrupt(sch);
 207        return 0;
 208    }
 209}
 210
 211static int vfio_ccw_handle_halt(SubchDev *sch)
 212{
 213    S390CCWDevice *cdev = sch->driver_data;
 214    VFIOCCWDevice *vcdev = DO_UPCAST(VFIOCCWDevice, cdev, cdev);
 215    struct ccw_cmd_region *region = vcdev->async_cmd_region;
 216    int ret;
 217
 218    if (!vcdev->async_cmd_region) {
 219        /* Async command region not available, fall back to emulation */
 220        return -ENOSYS;
 221    }
 222
 223    memset(region, 0, sizeof(*region));
 224    region->command = VFIO_CCW_ASYNC_CMD_HSCH;
 225
 226again:
 227    ret = pwrite(vcdev->vdev.fd, region,
 228                 vcdev->async_cmd_region_size, vcdev->async_cmd_region_offset);
 229    if (ret != vcdev->async_cmd_region_size) {
 230        if (errno == EAGAIN) {
 231            goto again;
 232        }
 233        error_report("vfio-ccw: write cmd region failed with errno=%d", errno);
 234        ret = errno ? -errno : -EFAULT;
 235    } else {
 236        ret = 0;
 237    }
 238    switch (ret) {
 239    case 0:
 240    case -EBUSY:
 241    case -ENODEV:
 242    case -EACCES:
 243        return ret;
 244    case -EFAULT:
 245    default:
 246        sch_gen_unit_exception(sch);
 247        css_inject_io_interrupt(sch);
 248        return 0;
 249    }
 250}
 251
 252static void vfio_ccw_reset(DeviceState *dev)
 253{
 254    CcwDevice *ccw_dev = DO_UPCAST(CcwDevice, parent_obj, dev);
 255    S390CCWDevice *cdev = DO_UPCAST(S390CCWDevice, parent_obj, ccw_dev);
 256    VFIOCCWDevice *vcdev = DO_UPCAST(VFIOCCWDevice, cdev, cdev);
 257
 258    ioctl(vcdev->vdev.fd, VFIO_DEVICE_RESET);
 259}
 260
 261static void vfio_ccw_crw_read(VFIOCCWDevice *vcdev)
 262{
 263    struct ccw_crw_region *region = vcdev->crw_region;
 264    CRW crw;
 265    int size;
 266
 267    /* Keep reading CRWs as long as data is returned */
 268    do {
 269        memset(region, 0, sizeof(*region));
 270        size = pread(vcdev->vdev.fd, region, vcdev->crw_region_size,
 271                     vcdev->crw_region_offset);
 272
 273        if (size == -1) {
 274            error_report("vfio-ccw: Read crw region failed with errno=%d",
 275                         errno);
 276            break;
 277        }
 278
 279        if (region->crw == 0) {
 280            /* No more CRWs to queue */
 281            break;
 282        }
 283
 284        memcpy(&crw, &region->crw, sizeof(CRW));
 285
 286        css_crw_add_to_queue(crw);
 287    } while (1);
 288}
 289
 290static void vfio_ccw_req_notifier_handler(void *opaque)
 291{
 292    VFIOCCWDevice *vcdev = opaque;
 293    Error *err = NULL;
 294
 295    if (!event_notifier_test_and_clear(&vcdev->req_notifier)) {
 296        return;
 297    }
 298
 299    qdev_unplug(DEVICE(vcdev), &err);
 300    if (err) {
 301        warn_reportf_err(err, VFIO_MSG_PREFIX, vcdev->vdev.name);
 302    }
 303}
 304
 305static void vfio_ccw_crw_notifier_handler(void *opaque)
 306{
 307    VFIOCCWDevice *vcdev = opaque;
 308
 309    while (event_notifier_test_and_clear(&vcdev->crw_notifier)) {
 310        vfio_ccw_crw_read(vcdev);
 311    }
 312}
 313
 314static void vfio_ccw_io_notifier_handler(void *opaque)
 315{
 316    VFIOCCWDevice *vcdev = opaque;
 317    struct ccw_io_region *region = vcdev->io_region;
 318    S390CCWDevice *cdev = S390_CCW_DEVICE(vcdev);
 319    CcwDevice *ccw_dev = CCW_DEVICE(cdev);
 320    SubchDev *sch = ccw_dev->sch;
 321    SCHIB *schib = &sch->curr_status;
 322    SCSW s;
 323    IRB irb;
 324    ESW esw;
 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    copy_esw_to_guest(&esw, &irb.esw);
 376    sch->esw = esw;
 377
 378    /* If a uint check is pending, copy sense data. */
 379    if ((schib->scsw.dstat & SCSW_DSTAT_UNIT_CHECK) &&
 380        (schib->pmcw.chars & PMCW_CHARS_MASK_CSENSE)) {
 381        memcpy(sch->sense_data, irb.ecw, sizeof(irb.ecw));
 382    }
 383
 384read_err:
 385    css_inject_io_interrupt(sch);
 386}
 387
 388static void vfio_ccw_register_irq_notifier(VFIOCCWDevice *vcdev,
 389                                           unsigned int irq,
 390                                           Error **errp)
 391{
 392    VFIODevice *vdev = &vcdev->vdev;
 393    struct vfio_irq_info *irq_info;
 394    size_t argsz;
 395    int fd;
 396    EventNotifier *notifier;
 397    IOHandler *fd_read;
 398
 399    switch (irq) {
 400    case VFIO_CCW_IO_IRQ_INDEX:
 401        notifier = &vcdev->io_notifier;
 402        fd_read = vfio_ccw_io_notifier_handler;
 403        break;
 404    case VFIO_CCW_CRW_IRQ_INDEX:
 405        notifier = &vcdev->crw_notifier;
 406        fd_read = vfio_ccw_crw_notifier_handler;
 407        break;
 408    case VFIO_CCW_REQ_IRQ_INDEX:
 409        notifier = &vcdev->req_notifier;
 410        fd_read = vfio_ccw_req_notifier_handler;
 411        break;
 412    default:
 413        error_setg(errp, "vfio: Unsupported device irq(%d)", irq);
 414        return;
 415    }
 416
 417    if (vdev->num_irqs < irq + 1) {
 418        error_setg(errp, "vfio: IRQ %u not available (number of irqs %u)",
 419                   irq, vdev->num_irqs);
 420        return;
 421    }
 422
 423    argsz = sizeof(*irq_info);
 424    irq_info = g_malloc0(argsz);
 425    irq_info->index = irq;
 426    irq_info->argsz = argsz;
 427    if (ioctl(vdev->fd, VFIO_DEVICE_GET_IRQ_INFO,
 428              irq_info) < 0 || irq_info->count < 1) {
 429        error_setg_errno(errp, errno, "vfio: Error getting irq info");
 430        goto out_free_info;
 431    }
 432
 433    if (event_notifier_init(notifier, 0)) {
 434        error_setg_errno(errp, errno,
 435                         "vfio: Unable to init event notifier for irq (%d)",
 436                         irq);
 437        goto out_free_info;
 438    }
 439
 440    fd = event_notifier_get_fd(notifier);
 441    qemu_set_fd_handler(fd, fd_read, NULL, vcdev);
 442
 443    if (vfio_set_irq_signaling(vdev, irq, 0,
 444                               VFIO_IRQ_SET_ACTION_TRIGGER, fd, errp)) {
 445        qemu_set_fd_handler(fd, NULL, NULL, vcdev);
 446        event_notifier_cleanup(notifier);
 447    }
 448
 449out_free_info:
 450    g_free(irq_info);
 451}
 452
 453static void vfio_ccw_unregister_irq_notifier(VFIOCCWDevice *vcdev,
 454                                             unsigned int irq)
 455{
 456    Error *err = NULL;
 457    EventNotifier *notifier;
 458
 459    switch (irq) {
 460    case VFIO_CCW_IO_IRQ_INDEX:
 461        notifier = &vcdev->io_notifier;
 462        break;
 463    case VFIO_CCW_CRW_IRQ_INDEX:
 464        notifier = &vcdev->crw_notifier;
 465        break;
 466    case VFIO_CCW_REQ_IRQ_INDEX:
 467        notifier = &vcdev->req_notifier;
 468        break;
 469    default:
 470        error_report("vfio: Unsupported device irq(%d)", irq);
 471        return;
 472    }
 473
 474    if (vfio_set_irq_signaling(&vcdev->vdev, irq, 0,
 475                               VFIO_IRQ_SET_ACTION_TRIGGER, -1, &err)) {
 476        warn_reportf_err(err, VFIO_MSG_PREFIX, vcdev->vdev.name);
 477    }
 478
 479    qemu_set_fd_handler(event_notifier_get_fd(notifier),
 480                        NULL, NULL, vcdev);
 481    event_notifier_cleanup(notifier);
 482}
 483
 484static void vfio_ccw_get_region(VFIOCCWDevice *vcdev, Error **errp)
 485{
 486    VFIODevice *vdev = &vcdev->vdev;
 487    struct vfio_region_info *info;
 488    int ret;
 489
 490    /* Sanity check device */
 491    if (!(vdev->flags & VFIO_DEVICE_FLAGS_CCW)) {
 492        error_setg(errp, "vfio: Um, this isn't a vfio-ccw device");
 493        return;
 494    }
 495
 496    /*
 497     * We always expect at least the I/O region to be present. We also
 498     * may have a variable number of regions governed by capabilities.
 499     */
 500    if (vdev->num_regions < VFIO_CCW_CONFIG_REGION_INDEX + 1) {
 501        error_setg(errp, "vfio: too few regions (%u), expected at least %u",
 502                   vdev->num_regions, VFIO_CCW_CONFIG_REGION_INDEX + 1);
 503        return;
 504    }
 505
 506    ret = vfio_get_region_info(vdev, VFIO_CCW_CONFIG_REGION_INDEX, &info);
 507    if (ret) {
 508        error_setg_errno(errp, -ret, "vfio: Error getting config info");
 509        return;
 510    }
 511
 512    vcdev->io_region_size = info->size;
 513    if (sizeof(*vcdev->io_region) != vcdev->io_region_size) {
 514        error_setg(errp, "vfio: Unexpected size of the I/O region");
 515        goto out_err;
 516    }
 517
 518    vcdev->io_region_offset = info->offset;
 519    vcdev->io_region = g_malloc0(info->size);
 520    g_free(info);
 521
 522    /* check for the optional async command region */
 523    ret = vfio_get_dev_region_info(vdev, VFIO_REGION_TYPE_CCW,
 524                                   VFIO_REGION_SUBTYPE_CCW_ASYNC_CMD, &info);
 525    if (!ret) {
 526        vcdev->async_cmd_region_size = info->size;
 527        if (sizeof(*vcdev->async_cmd_region) != vcdev->async_cmd_region_size) {
 528            error_setg(errp, "vfio: Unexpected size of the async cmd region");
 529            goto out_err;
 530        }
 531        vcdev->async_cmd_region_offset = info->offset;
 532        vcdev->async_cmd_region = g_malloc0(info->size);
 533        g_free(info);
 534    }
 535
 536    ret = vfio_get_dev_region_info(vdev, VFIO_REGION_TYPE_CCW,
 537                                   VFIO_REGION_SUBTYPE_CCW_SCHIB, &info);
 538    if (!ret) {
 539        vcdev->schib_region_size = info->size;
 540        if (sizeof(*vcdev->schib_region) != vcdev->schib_region_size) {
 541            error_setg(errp, "vfio: Unexpected size of the schib region");
 542            goto out_err;
 543        }
 544        vcdev->schib_region_offset = info->offset;
 545        vcdev->schib_region = g_malloc(info->size);
 546        g_free(info);
 547    }
 548
 549    ret = vfio_get_dev_region_info(vdev, VFIO_REGION_TYPE_CCW,
 550                                   VFIO_REGION_SUBTYPE_CCW_CRW, &info);
 551
 552    if (!ret) {
 553        vcdev->crw_region_size = info->size;
 554        if (sizeof(*vcdev->crw_region) != vcdev->crw_region_size) {
 555            error_setg(errp, "vfio: Unexpected size of the CRW region");
 556            goto out_err;
 557        }
 558        vcdev->crw_region_offset = info->offset;
 559        vcdev->crw_region = g_malloc(info->size);
 560        g_free(info);
 561    }
 562
 563    return;
 564
 565out_err:
 566    g_free(vcdev->crw_region);
 567    g_free(vcdev->schib_region);
 568    g_free(vcdev->async_cmd_region);
 569    g_free(vcdev->io_region);
 570    g_free(info);
 571    return;
 572}
 573
 574static void vfio_ccw_put_region(VFIOCCWDevice *vcdev)
 575{
 576    g_free(vcdev->crw_region);
 577    g_free(vcdev->schib_region);
 578    g_free(vcdev->async_cmd_region);
 579    g_free(vcdev->io_region);
 580}
 581
 582static void vfio_ccw_put_device(VFIOCCWDevice *vcdev)
 583{
 584    g_free(vcdev->vdev.name);
 585    vfio_put_base_device(&vcdev->vdev);
 586}
 587
 588static void vfio_ccw_get_device(VFIOGroup *group, VFIOCCWDevice *vcdev,
 589                                Error **errp)
 590{
 591    char *name = g_strdup_printf("%x.%x.%04x", vcdev->cdev.hostid.cssid,
 592                                 vcdev->cdev.hostid.ssid,
 593                                 vcdev->cdev.hostid.devid);
 594    VFIODevice *vbasedev;
 595
 596    QLIST_FOREACH(vbasedev, &group->device_list, next) {
 597        if (strcmp(vbasedev->name, name) == 0) {
 598            error_setg(errp, "vfio: subchannel %s has already been attached",
 599                       name);
 600            goto out_err;
 601        }
 602    }
 603
 604    /*
 605     * All vfio-ccw devices are believed to operate in a way compatible with
 606     * discarding of memory in RAM blocks, ie. pages pinned in the host are
 607     * in the current working set of the guest driver and therefore never
 608     * overlap e.g., with pages available to the guest balloon driver.  This
 609     * needs to be set before vfio_get_device() for vfio common to handle
 610     * ram_block_discard_disable().
 611     */
 612    vcdev->vdev.ram_block_discard_allowed = true;
 613
 614    if (vfio_get_device(group, vcdev->cdev.mdevid, &vcdev->vdev, errp)) {
 615        goto out_err;
 616    }
 617
 618    vcdev->vdev.ops = &vfio_ccw_ops;
 619    vcdev->vdev.type = VFIO_DEVICE_TYPE_CCW;
 620    vcdev->vdev.name = name;
 621    vcdev->vdev.dev = &vcdev->cdev.parent_obj.parent_obj;
 622
 623    return;
 624
 625out_err:
 626    g_free(name);
 627}
 628
 629static VFIOGroup *vfio_ccw_get_group(S390CCWDevice *cdev, Error **errp)
 630{
 631    char *tmp, group_path[PATH_MAX];
 632    ssize_t len;
 633    int groupid;
 634
 635    tmp = g_strdup_printf("/sys/bus/css/devices/%x.%x.%04x/%s/iommu_group",
 636                          cdev->hostid.cssid, cdev->hostid.ssid,
 637                          cdev->hostid.devid, cdev->mdevid);
 638    len = readlink(tmp, group_path, sizeof(group_path));
 639    g_free(tmp);
 640
 641    if (len <= 0 || len >= sizeof(group_path)) {
 642        error_setg(errp, "vfio: no iommu_group found");
 643        return NULL;
 644    }
 645
 646    group_path[len] = 0;
 647
 648    if (sscanf(basename(group_path), "%d", &groupid) != 1) {
 649        error_setg(errp, "vfio: failed to read %s", group_path);
 650        return NULL;
 651    }
 652
 653    return vfio_get_group(groupid, &address_space_memory, errp);
 654}
 655
 656static void vfio_ccw_realize(DeviceState *dev, Error **errp)
 657{
 658    VFIOGroup *group;
 659    CcwDevice *ccw_dev = DO_UPCAST(CcwDevice, parent_obj, dev);
 660    S390CCWDevice *cdev = DO_UPCAST(S390CCWDevice, parent_obj, ccw_dev);
 661    VFIOCCWDevice *vcdev = DO_UPCAST(VFIOCCWDevice, cdev, cdev);
 662    S390CCWDeviceClass *cdc = S390_CCW_DEVICE_GET_CLASS(cdev);
 663    Error *err = NULL;
 664
 665    /* Call the class init function for subchannel. */
 666    if (cdc->realize) {
 667        cdc->realize(cdev, vcdev->vdev.sysfsdev, &err);
 668        if (err) {
 669            goto out_err_propagate;
 670        }
 671    }
 672
 673    group = vfio_ccw_get_group(cdev, &err);
 674    if (!group) {
 675        goto out_group_err;
 676    }
 677
 678    vfio_ccw_get_device(group, vcdev, &err);
 679    if (err) {
 680        goto out_device_err;
 681    }
 682
 683    vfio_ccw_get_region(vcdev, &err);
 684    if (err) {
 685        goto out_region_err;
 686    }
 687
 688    vfio_ccw_register_irq_notifier(vcdev, VFIO_CCW_IO_IRQ_INDEX, &err);
 689    if (err) {
 690        goto out_io_notifier_err;
 691    }
 692
 693    if (vcdev->crw_region) {
 694        vfio_ccw_register_irq_notifier(vcdev, VFIO_CCW_CRW_IRQ_INDEX, &err);
 695        if (err) {
 696            goto out_irq_notifier_err;
 697        }
 698    }
 699
 700    vfio_ccw_register_irq_notifier(vcdev, VFIO_CCW_REQ_IRQ_INDEX, &err);
 701    if (err) {
 702        /*
 703         * Report this error, but do not make it a failing condition.
 704         * Lack of this IRQ in the host does not prevent normal operation.
 705         */
 706        error_report_err(err);
 707    }
 708
 709    return;
 710
 711out_irq_notifier_err:
 712    vfio_ccw_unregister_irq_notifier(vcdev, VFIO_CCW_REQ_IRQ_INDEX);
 713    vfio_ccw_unregister_irq_notifier(vcdev, VFIO_CCW_CRW_IRQ_INDEX);
 714    vfio_ccw_unregister_irq_notifier(vcdev, VFIO_CCW_IO_IRQ_INDEX);
 715out_io_notifier_err:
 716    vfio_ccw_put_region(vcdev);
 717out_region_err:
 718    vfio_ccw_put_device(vcdev);
 719out_device_err:
 720    vfio_put_group(group);
 721out_group_err:
 722    if (cdc->unrealize) {
 723        cdc->unrealize(cdev);
 724    }
 725out_err_propagate:
 726    error_propagate(errp, err);
 727}
 728
 729static void vfio_ccw_unrealize(DeviceState *dev)
 730{
 731    CcwDevice *ccw_dev = DO_UPCAST(CcwDevice, parent_obj, dev);
 732    S390CCWDevice *cdev = DO_UPCAST(S390CCWDevice, parent_obj, ccw_dev);
 733    VFIOCCWDevice *vcdev = DO_UPCAST(VFIOCCWDevice, cdev, cdev);
 734    S390CCWDeviceClass *cdc = S390_CCW_DEVICE_GET_CLASS(cdev);
 735    VFIOGroup *group = vcdev->vdev.group;
 736
 737    vfio_ccw_unregister_irq_notifier(vcdev, VFIO_CCW_REQ_IRQ_INDEX);
 738    vfio_ccw_unregister_irq_notifier(vcdev, VFIO_CCW_CRW_IRQ_INDEX);
 739    vfio_ccw_unregister_irq_notifier(vcdev, VFIO_CCW_IO_IRQ_INDEX);
 740    vfio_ccw_put_region(vcdev);
 741    vfio_ccw_put_device(vcdev);
 742    vfio_put_group(group);
 743
 744    if (cdc->unrealize) {
 745        cdc->unrealize(cdev);
 746    }
 747}
 748
 749static Property vfio_ccw_properties[] = {
 750    DEFINE_PROP_STRING("sysfsdev", VFIOCCWDevice, vdev.sysfsdev),
 751    DEFINE_PROP_BOOL("force-orb-pfch", VFIOCCWDevice, force_orb_pfch, false),
 752    DEFINE_PROP_END_OF_LIST(),
 753};
 754
 755static const VMStateDescription vfio_ccw_vmstate = {
 756    .name = "vfio-ccw",
 757    .unmigratable = 1,
 758};
 759
 760static void vfio_ccw_class_init(ObjectClass *klass, void *data)
 761{
 762    DeviceClass *dc = DEVICE_CLASS(klass);
 763    S390CCWDeviceClass *cdc = S390_CCW_DEVICE_CLASS(klass);
 764
 765    device_class_set_props(dc, vfio_ccw_properties);
 766    dc->vmsd = &vfio_ccw_vmstate;
 767    dc->desc = "VFIO-based subchannel assignment";
 768    set_bit(DEVICE_CATEGORY_MISC, dc->categories);
 769    dc->realize = vfio_ccw_realize;
 770    dc->unrealize = vfio_ccw_unrealize;
 771    dc->reset = vfio_ccw_reset;
 772
 773    cdc->handle_request = vfio_ccw_handle_request;
 774    cdc->handle_halt = vfio_ccw_handle_halt;
 775    cdc->handle_clear = vfio_ccw_handle_clear;
 776    cdc->handle_store = vfio_ccw_handle_store;
 777}
 778
 779static const TypeInfo vfio_ccw_info = {
 780    .name = TYPE_VFIO_CCW,
 781    .parent = TYPE_S390_CCW,
 782    .instance_size = sizeof(VFIOCCWDevice),
 783    .class_init = vfio_ccw_class_init,
 784};
 785
 786static void register_vfio_ccw_type(void)
 787{
 788    type_register_static(&vfio_ccw_info);
 789}
 790
 791type_init(register_vfio_ccw_type)
 792