| /* |
| * vfio based subchannel assignment support |
| * |
| * Copyright 2017 IBM Corp. |
| * Author(s): Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com> |
| * Xiao Feng Ren <renxiaof@linux.vnet.ibm.com> |
| * Pierre Morel <pmorel@linux.vnet.ibm.com> |
| * |
| * This work is licensed under the terms of the GNU GPL, version 2 or (at |
| * your option) any later version. See the COPYING file in the top-level |
| * directory. |
| */ |
| |
| #include "qemu/osdep.h" |
| #include <linux/vfio.h> |
| #include <linux/vfio_ccw.h> |
| #include <sys/ioctl.h> |
| |
| #include "qapi/error.h" |
| #include "hw/sysbus.h" |
| #include "hw/vfio/vfio.h" |
| #include "hw/vfio/vfio-common.h" |
| #include "hw/s390x/s390-ccw.h" |
| #include "hw/s390x/ccw-device.h" |
| #include "exec/address-spaces.h" |
| #include "qemu/error-report.h" |
| |
| #define TYPE_VFIO_CCW "vfio-ccw" |
| typedef struct VFIOCCWDevice { |
| S390CCWDevice cdev; |
| VFIODevice vdev; |
| uint64_t io_region_size; |
| uint64_t io_region_offset; |
| struct ccw_io_region *io_region; |
| EventNotifier io_notifier; |
| bool force_orb_pfch; |
| bool warned_orb_pfch; |
| } VFIOCCWDevice; |
| |
| static inline void warn_once(bool *warned, const char *fmt, ...) |
| { |
| va_list ap; |
| |
| if (!warned || *warned) { |
| return; |
| } |
| *warned = true; |
| va_start(ap, fmt); |
| warn_vreport(fmt, ap); |
| va_end(ap); |
| } |
| |
| static inline void warn_once_pfch(VFIOCCWDevice *vcdev, SubchDev *sch, |
| const char *msg) |
| { |
| warn_once(&vcdev->warned_orb_pfch, "vfio-ccw (devno %x.%x.%04x): %s", |
| sch->cssid, sch->ssid, sch->devno, msg); |
| } |
| |
| static void vfio_ccw_compute_needs_reset(VFIODevice *vdev) |
| { |
| vdev->needs_reset = false; |
| } |
| |
| /* |
| * We don't need vfio_hot_reset_multi and vfio_eoi operations for |
| * vfio_ccw device now. |
| */ |
| struct VFIODeviceOps vfio_ccw_ops = { |
| .vfio_compute_needs_reset = vfio_ccw_compute_needs_reset, |
| }; |
| |
| static IOInstEnding vfio_ccw_handle_request(SubchDev *sch) |
| { |
| S390CCWDevice *cdev = sch->driver_data; |
| VFIOCCWDevice *vcdev = DO_UPCAST(VFIOCCWDevice, cdev, cdev); |
| struct ccw_io_region *region = vcdev->io_region; |
| int ret; |
| |
| if (!(sch->orb.ctrl0 & ORB_CTRL0_MASK_PFCH)) { |
| if (!(vcdev->force_orb_pfch)) { |
| warn_once_pfch(vcdev, sch, "requires PFCH flag set"); |
| sch_gen_unit_exception(sch); |
| css_inject_io_interrupt(sch); |
| return IOINST_CC_EXPECTED; |
| } else { |
| sch->orb.ctrl0 |= ORB_CTRL0_MASK_PFCH; |
| warn_once_pfch(vcdev, sch, "PFCH flag forced"); |
| } |
| } |
| |
| QEMU_BUILD_BUG_ON(sizeof(region->orb_area) != sizeof(ORB)); |
| QEMU_BUILD_BUG_ON(sizeof(region->scsw_area) != sizeof(SCSW)); |
| QEMU_BUILD_BUG_ON(sizeof(region->irb_area) != sizeof(IRB)); |
| |
| memset(region, 0, sizeof(*region)); |
| |
| memcpy(region->orb_area, &sch->orb, sizeof(ORB)); |
| memcpy(region->scsw_area, &sch->curr_status.scsw, sizeof(SCSW)); |
| |
| again: |
| ret = pwrite(vcdev->vdev.fd, region, |
| vcdev->io_region_size, vcdev->io_region_offset); |
| if (ret != vcdev->io_region_size) { |
| if (errno == EAGAIN) { |
| goto again; |
| } |
| error_report("vfio-ccw: wirte I/O region failed with errno=%d", errno); |
| ret = -errno; |
| } else { |
| ret = region->ret_code; |
| } |
| switch (ret) { |
| case 0: |
| return IOINST_CC_EXPECTED; |
| case -EBUSY: |
| return IOINST_CC_BUSY; |
| case -ENODEV: |
| case -EACCES: |
| return IOINST_CC_NOT_OPERATIONAL; |
| case -EFAULT: |
| default: |
| sch_gen_unit_exception(sch); |
| css_inject_io_interrupt(sch); |
| return IOINST_CC_EXPECTED; |
| } |
| } |
| |
| static void vfio_ccw_reset(DeviceState *dev) |
| { |
| CcwDevice *ccw_dev = DO_UPCAST(CcwDevice, parent_obj, dev); |
| S390CCWDevice *cdev = DO_UPCAST(S390CCWDevice, parent_obj, ccw_dev); |
| VFIOCCWDevice *vcdev = DO_UPCAST(VFIOCCWDevice, cdev, cdev); |
| |
| ioctl(vcdev->vdev.fd, VFIO_DEVICE_RESET); |
| } |
| |
| static void vfio_ccw_io_notifier_handler(void *opaque) |
| { |
| VFIOCCWDevice *vcdev = opaque; |
| struct ccw_io_region *region = vcdev->io_region; |
| S390CCWDevice *cdev = S390_CCW_DEVICE(vcdev); |
| CcwDevice *ccw_dev = CCW_DEVICE(cdev); |
| SubchDev *sch = ccw_dev->sch; |
| SCSW *s = &sch->curr_status.scsw; |
| PMCW *p = &sch->curr_status.pmcw; |
| IRB irb; |
| int size; |
| |
| if (!event_notifier_test_and_clear(&vcdev->io_notifier)) { |
| return; |
| } |
| |
| size = pread(vcdev->vdev.fd, region, vcdev->io_region_size, |
| vcdev->io_region_offset); |
| if (size == -1) { |
| switch (errno) { |
| case ENODEV: |
| /* Generate a deferred cc 3 condition. */ |
| s->flags |= SCSW_FLAGS_MASK_CC; |
| s->ctrl &= ~SCSW_CTRL_MASK_STCTL; |
| s->ctrl |= (SCSW_STCTL_ALERT | SCSW_STCTL_STATUS_PEND); |
| goto read_err; |
| case EFAULT: |
| /* Memory problem, generate channel data check. */ |
| s->ctrl &= ~SCSW_ACTL_START_PEND; |
| s->cstat = SCSW_CSTAT_DATA_CHECK; |
| s->ctrl &= ~SCSW_CTRL_MASK_STCTL; |
| s->ctrl |= SCSW_STCTL_PRIMARY | SCSW_STCTL_SECONDARY | |
| SCSW_STCTL_ALERT | SCSW_STCTL_STATUS_PEND; |
| goto read_err; |
| default: |
| /* Error, generate channel program check. */ |
| s->ctrl &= ~SCSW_ACTL_START_PEND; |
| s->cstat = SCSW_CSTAT_PROG_CHECK; |
| s->ctrl &= ~SCSW_CTRL_MASK_STCTL; |
| s->ctrl |= SCSW_STCTL_PRIMARY | SCSW_STCTL_SECONDARY | |
| SCSW_STCTL_ALERT | SCSW_STCTL_STATUS_PEND; |
| goto read_err; |
| } |
| } else if (size != vcdev->io_region_size) { |
| /* Information transfer error, generate channel-control check. */ |
| s->ctrl &= ~SCSW_ACTL_START_PEND; |
| s->cstat = SCSW_CSTAT_CHN_CTRL_CHK; |
| s->ctrl &= ~SCSW_CTRL_MASK_STCTL; |
| s->ctrl |= SCSW_STCTL_PRIMARY | SCSW_STCTL_SECONDARY | |
| SCSW_STCTL_ALERT | SCSW_STCTL_STATUS_PEND; |
| goto read_err; |
| } |
| |
| memcpy(&irb, region->irb_area, sizeof(IRB)); |
| |
| /* Update control block via irb. */ |
| copy_scsw_to_guest(s, &irb.scsw); |
| |
| /* If a uint check is pending, copy sense data. */ |
| if ((s->dstat & SCSW_DSTAT_UNIT_CHECK) && |
| (p->chars & PMCW_CHARS_MASK_CSENSE)) { |
| memcpy(sch->sense_data, irb.ecw, sizeof(irb.ecw)); |
| } |
| |
| read_err: |
| css_inject_io_interrupt(sch); |
| } |
| |
| static void vfio_ccw_register_io_notifier(VFIOCCWDevice *vcdev, Error **errp) |
| { |
| VFIODevice *vdev = &vcdev->vdev; |
| struct vfio_irq_info *irq_info; |
| struct vfio_irq_set *irq_set; |
| size_t argsz; |
| int32_t *pfd; |
| |
| if (vdev->num_irqs < VFIO_CCW_IO_IRQ_INDEX + 1) { |
| error_setg(errp, "vfio: unexpected number of io irqs %u", |
| vdev->num_irqs); |
| return; |
| } |
| |
| argsz = sizeof(*irq_info); |
| irq_info = g_malloc0(argsz); |
| irq_info->index = VFIO_CCW_IO_IRQ_INDEX; |
| irq_info->argsz = argsz; |
| if (ioctl(vdev->fd, VFIO_DEVICE_GET_IRQ_INFO, |
| irq_info) < 0 || irq_info->count < 1) { |
| error_setg_errno(errp, errno, "vfio: Error getting irq info"); |
| goto out_free_info; |
| } |
| |
| if (event_notifier_init(&vcdev->io_notifier, 0)) { |
| error_setg_errno(errp, errno, |
| "vfio: Unable to init event notifier for IO"); |
| goto out_free_info; |
| } |
| |
| argsz = sizeof(*irq_set) + sizeof(*pfd); |
| irq_set = g_malloc0(argsz); |
| irq_set->argsz = argsz; |
| irq_set->flags = VFIO_IRQ_SET_DATA_EVENTFD | |
| VFIO_IRQ_SET_ACTION_TRIGGER; |
| irq_set->index = VFIO_CCW_IO_IRQ_INDEX; |
| irq_set->start = 0; |
| irq_set->count = 1; |
| pfd = (int32_t *) &irq_set->data; |
| |
| *pfd = event_notifier_get_fd(&vcdev->io_notifier); |
| qemu_set_fd_handler(*pfd, vfio_ccw_io_notifier_handler, NULL, vcdev); |
| if (ioctl(vdev->fd, VFIO_DEVICE_SET_IRQS, irq_set)) { |
| error_setg(errp, "vfio: Failed to set up io notification"); |
| qemu_set_fd_handler(*pfd, NULL, NULL, vcdev); |
| event_notifier_cleanup(&vcdev->io_notifier); |
| } |
| |
| g_free(irq_set); |
| |
| out_free_info: |
| g_free(irq_info); |
| } |
| |
| static void vfio_ccw_unregister_io_notifier(VFIOCCWDevice *vcdev) |
| { |
| struct vfio_irq_set *irq_set; |
| size_t argsz; |
| int32_t *pfd; |
| |
| argsz = sizeof(*irq_set) + sizeof(*pfd); |
| irq_set = g_malloc0(argsz); |
| irq_set->argsz = argsz; |
| irq_set->flags = VFIO_IRQ_SET_DATA_EVENTFD | |
| VFIO_IRQ_SET_ACTION_TRIGGER; |
| irq_set->index = VFIO_CCW_IO_IRQ_INDEX; |
| irq_set->start = 0; |
| irq_set->count = 1; |
| pfd = (int32_t *) &irq_set->data; |
| *pfd = -1; |
| |
| if (ioctl(vcdev->vdev.fd, VFIO_DEVICE_SET_IRQS, irq_set)) { |
| error_report("vfio: Failed to de-assign device io fd: %m"); |
| } |
| |
| qemu_set_fd_handler(event_notifier_get_fd(&vcdev->io_notifier), |
| NULL, NULL, vcdev); |
| event_notifier_cleanup(&vcdev->io_notifier); |
| |
| g_free(irq_set); |
| } |
| |
| static void vfio_ccw_get_region(VFIOCCWDevice *vcdev, Error **errp) |
| { |
| VFIODevice *vdev = &vcdev->vdev; |
| struct vfio_region_info *info; |
| int ret; |
| |
| /* Sanity check device */ |
| if (!(vdev->flags & VFIO_DEVICE_FLAGS_CCW)) { |
| error_setg(errp, "vfio: Um, this isn't a vfio-ccw device"); |
| return; |
| } |
| |
| if (vdev->num_regions < VFIO_CCW_CONFIG_REGION_INDEX + 1) { |
| error_setg(errp, "vfio: Unexpected number of the I/O region %u", |
| vdev->num_regions); |
| return; |
| } |
| |
| ret = vfio_get_region_info(vdev, VFIO_CCW_CONFIG_REGION_INDEX, &info); |
| if (ret) { |
| error_setg_errno(errp, -ret, "vfio: Error getting config info"); |
| return; |
| } |
| |
| vcdev->io_region_size = info->size; |
| if (sizeof(*vcdev->io_region) != vcdev->io_region_size) { |
| error_setg(errp, "vfio: Unexpected size of the I/O region"); |
| g_free(info); |
| return; |
| } |
| |
| vcdev->io_region_offset = info->offset; |
| vcdev->io_region = g_malloc0(info->size); |
| |
| g_free(info); |
| } |
| |
| static void vfio_ccw_put_region(VFIOCCWDevice *vcdev) |
| { |
| g_free(vcdev->io_region); |
| } |
| |
| static void vfio_ccw_put_device(VFIOCCWDevice *vcdev) |
| { |
| g_free(vcdev->vdev.name); |
| vfio_put_base_device(&vcdev->vdev); |
| } |
| |
| static void vfio_ccw_get_device(VFIOGroup *group, VFIOCCWDevice *vcdev, |
| Error **errp) |
| { |
| char *name = g_strdup_printf("%x.%x.%04x", vcdev->cdev.hostid.cssid, |
| vcdev->cdev.hostid.ssid, |
| vcdev->cdev.hostid.devid); |
| VFIODevice *vbasedev; |
| |
| QLIST_FOREACH(vbasedev, &group->device_list, next) { |
| if (strcmp(vbasedev->name, name) == 0) { |
| error_setg(errp, "vfio: subchannel %s has already been attached", |
| name); |
| goto out_err; |
| } |
| } |
| |
| /* |
| * All vfio-ccw devices are believed to operate in a way compatible with |
| * memory ballooning, ie. pages pinned in the host are in the current |
| * working set of the guest driver and therefore never overlap with pages |
| * available to the guest balloon driver. This needs to be set before |
| * vfio_get_device() for vfio common to handle the balloon inhibitor. |
| */ |
| vcdev->vdev.balloon_allowed = true; |
| |
| if (vfio_get_device(group, vcdev->cdev.mdevid, &vcdev->vdev, errp)) { |
| goto out_err; |
| } |
| |
| vcdev->vdev.ops = &vfio_ccw_ops; |
| vcdev->vdev.type = VFIO_DEVICE_TYPE_CCW; |
| vcdev->vdev.name = name; |
| vcdev->vdev.dev = &vcdev->cdev.parent_obj.parent_obj; |
| |
| return; |
| |
| out_err: |
| g_free(name); |
| } |
| |
| static VFIOGroup *vfio_ccw_get_group(S390CCWDevice *cdev, Error **errp) |
| { |
| char *tmp, group_path[PATH_MAX]; |
| ssize_t len; |
| int groupid; |
| |
| tmp = g_strdup_printf("/sys/bus/css/devices/%x.%x.%04x/%s/iommu_group", |
| cdev->hostid.cssid, cdev->hostid.ssid, |
| cdev->hostid.devid, cdev->mdevid); |
| len = readlink(tmp, group_path, sizeof(group_path)); |
| g_free(tmp); |
| |
| if (len <= 0 || len >= sizeof(group_path)) { |
| error_setg(errp, "vfio: no iommu_group found"); |
| return NULL; |
| } |
| |
| group_path[len] = 0; |
| |
| if (sscanf(basename(group_path), "%d", &groupid) != 1) { |
| error_setg(errp, "vfio: failed to read %s", group_path); |
| return NULL; |
| } |
| |
| return vfio_get_group(groupid, &address_space_memory, errp); |
| } |
| |
| static void vfio_ccw_realize(DeviceState *dev, Error **errp) |
| { |
| VFIOGroup *group; |
| CcwDevice *ccw_dev = DO_UPCAST(CcwDevice, parent_obj, dev); |
| S390CCWDevice *cdev = DO_UPCAST(S390CCWDevice, parent_obj, ccw_dev); |
| VFIOCCWDevice *vcdev = DO_UPCAST(VFIOCCWDevice, cdev, cdev); |
| S390CCWDeviceClass *cdc = S390_CCW_DEVICE_GET_CLASS(cdev); |
| Error *err = NULL; |
| |
| /* Call the class init function for subchannel. */ |
| if (cdc->realize) { |
| cdc->realize(cdev, vcdev->vdev.sysfsdev, &err); |
| if (err) { |
| goto out_err_propagate; |
| } |
| } |
| |
| group = vfio_ccw_get_group(cdev, &err); |
| if (!group) { |
| goto out_group_err; |
| } |
| |
| vfio_ccw_get_device(group, vcdev, &err); |
| if (err) { |
| goto out_device_err; |
| } |
| |
| vfio_ccw_get_region(vcdev, &err); |
| if (err) { |
| goto out_region_err; |
| } |
| |
| vfio_ccw_register_io_notifier(vcdev, &err); |
| if (err) { |
| goto out_notifier_err; |
| } |
| |
| return; |
| |
| out_notifier_err: |
| vfio_ccw_put_region(vcdev); |
| out_region_err: |
| vfio_ccw_put_device(vcdev); |
| out_device_err: |
| vfio_put_group(group); |
| out_group_err: |
| if (cdc->unrealize) { |
| cdc->unrealize(cdev, NULL); |
| } |
| out_err_propagate: |
| error_propagate(errp, err); |
| } |
| |
| static void vfio_ccw_unrealize(DeviceState *dev, Error **errp) |
| { |
| CcwDevice *ccw_dev = DO_UPCAST(CcwDevice, parent_obj, dev); |
| S390CCWDevice *cdev = DO_UPCAST(S390CCWDevice, parent_obj, ccw_dev); |
| VFIOCCWDevice *vcdev = DO_UPCAST(VFIOCCWDevice, cdev, cdev); |
| S390CCWDeviceClass *cdc = S390_CCW_DEVICE_GET_CLASS(cdev); |
| VFIOGroup *group = vcdev->vdev.group; |
| |
| vfio_ccw_unregister_io_notifier(vcdev); |
| vfio_ccw_put_region(vcdev); |
| vfio_ccw_put_device(vcdev); |
| vfio_put_group(group); |
| |
| if (cdc->unrealize) { |
| cdc->unrealize(cdev, errp); |
| } |
| } |
| |
| static Property vfio_ccw_properties[] = { |
| DEFINE_PROP_STRING("sysfsdev", VFIOCCWDevice, vdev.sysfsdev), |
| DEFINE_PROP_BOOL("force-orb-pfch", VFIOCCWDevice, force_orb_pfch, false), |
| DEFINE_PROP_END_OF_LIST(), |
| }; |
| |
| static const VMStateDescription vfio_ccw_vmstate = { |
| .name = TYPE_VFIO_CCW, |
| .unmigratable = 1, |
| }; |
| |
| static void vfio_ccw_class_init(ObjectClass *klass, void *data) |
| { |
| DeviceClass *dc = DEVICE_CLASS(klass); |
| S390CCWDeviceClass *cdc = S390_CCW_DEVICE_CLASS(klass); |
| |
| dc->props = vfio_ccw_properties; |
| dc->vmsd = &vfio_ccw_vmstate; |
| dc->desc = "VFIO-based subchannel assignment"; |
| set_bit(DEVICE_CATEGORY_MISC, dc->categories); |
| dc->realize = vfio_ccw_realize; |
| dc->unrealize = vfio_ccw_unrealize; |
| dc->reset = vfio_ccw_reset; |
| |
| cdc->handle_request = vfio_ccw_handle_request; |
| } |
| |
| static const TypeInfo vfio_ccw_info = { |
| .name = TYPE_VFIO_CCW, |
| .parent = TYPE_S390_CCW, |
| .instance_size = sizeof(VFIOCCWDevice), |
| .class_init = vfio_ccw_class_init, |
| }; |
| |
| static void register_vfio_ccw_type(void) |
| { |
| type_register_static(&vfio_ccw_info); |
| } |
| |
| type_init(register_vfio_ccw_type) |