diff options
Diffstat (limited to 'qemu/hw/scsi/virtio-scsi.c')
| -rw-r--r-- | qemu/hw/scsi/virtio-scsi.c | 1016 |
1 files changed, 1016 insertions, 0 deletions
diff --git a/qemu/hw/scsi/virtio-scsi.c b/qemu/hw/scsi/virtio-scsi.c new file mode 100644 index 000000000..811c3da8b --- /dev/null +++ b/qemu/hw/scsi/virtio-scsi.c @@ -0,0 +1,1016 @@ +/* + * Virtio SCSI HBA + * + * Copyright IBM, Corp. 2010 + * Copyright Red Hat, Inc. 2011 + * + * Authors: + * Stefan Hajnoczi <stefanha@linux.vnet.ibm.com> + * Paolo Bonzini <pbonzini@redhat.com> + * + * This work is licensed under the terms of the GNU GPL, version 2 or later. + * See the COPYING file in the top-level directory. + * + */ + +#include "standard-headers/linux/virtio_ids.h" +#include "hw/virtio/virtio-scsi.h" +#include "qemu/error-report.h" +#include "qemu/iov.h" +#include "sysemu/block-backend.h" +#include <hw/scsi/scsi.h> +#include <block/scsi.h> +#include <hw/virtio/virtio-bus.h> +#include "hw/virtio/virtio-access.h" +#include "migration/migration.h" + +static inline int virtio_scsi_get_lun(uint8_t *lun) +{ + return ((lun[2] << 8) | lun[3]) & 0x3FFF; +} + +static inline SCSIDevice *virtio_scsi_device_find(VirtIOSCSI *s, uint8_t *lun) +{ + if (lun[0] != 1) { + return NULL; + } + if (lun[2] != 0 && !(lun[2] >= 0x40 && lun[2] < 0x80)) { + return NULL; + } + return scsi_device_find(&s->bus, 0, lun[1], virtio_scsi_get_lun(lun)); +} + +VirtIOSCSIReq *virtio_scsi_init_req(VirtIOSCSI *s, VirtQueue *vq) +{ + VirtIOSCSIReq *req; + VirtIOSCSICommon *vs = (VirtIOSCSICommon *)s; + const size_t zero_skip = offsetof(VirtIOSCSIReq, elem) + + sizeof(VirtQueueElement); + + req = g_slice_alloc(sizeof(*req) + vs->cdb_size); + req->vq = vq; + req->dev = s; + qemu_sglist_init(&req->qsgl, DEVICE(s), 8, &address_space_memory); + qemu_iovec_init(&req->resp_iov, 1); + memset((uint8_t *)req + zero_skip, 0, sizeof(*req) - zero_skip); + return req; +} + +void virtio_scsi_free_req(VirtIOSCSIReq *req) +{ + VirtIOSCSICommon *vs = (VirtIOSCSICommon *)req->dev; + + qemu_iovec_destroy(&req->resp_iov); + qemu_sglist_destroy(&req->qsgl); + g_slice_free1(sizeof(*req) + vs->cdb_size, req); +} + +static void virtio_scsi_complete_req(VirtIOSCSIReq *req) +{ + VirtIOSCSI *s = req->dev; + VirtQueue *vq = req->vq; + VirtIODevice *vdev = VIRTIO_DEVICE(s); + + qemu_iovec_from_buf(&req->resp_iov, 0, &req->resp, req->resp_size); + if (req->vring) { + assert(req->vq == NULL); + virtio_scsi_vring_push_notify(req); + } else { + virtqueue_push(vq, &req->elem, req->qsgl.size + req->resp_iov.size); + virtio_notify(vdev, vq); + } + + if (req->sreq) { + req->sreq->hba_private = NULL; + scsi_req_unref(req->sreq); + } + virtio_scsi_free_req(req); +} + +static void virtio_scsi_bad_req(void) +{ + error_report("wrong size for virtio-scsi headers"); + exit(1); +} + +static size_t qemu_sgl_concat(VirtIOSCSIReq *req, struct iovec *iov, + hwaddr *addr, int num, size_t skip) +{ + QEMUSGList *qsgl = &req->qsgl; + size_t copied = 0; + + while (num) { + if (skip >= iov->iov_len) { + skip -= iov->iov_len; + } else { + qemu_sglist_add(qsgl, *addr + skip, iov->iov_len - skip); + copied += iov->iov_len - skip; + skip = 0; + } + iov++; + addr++; + num--; + } + + assert(skip == 0); + return copied; +} + +static int virtio_scsi_parse_req(VirtIOSCSIReq *req, + unsigned req_size, unsigned resp_size) +{ + VirtIODevice *vdev = (VirtIODevice *) req->dev; + size_t in_size, out_size; + + if (iov_to_buf(req->elem.out_sg, req->elem.out_num, 0, + &req->req, req_size) < req_size) { + return -EINVAL; + } + + if (qemu_iovec_concat_iov(&req->resp_iov, + req->elem.in_sg, req->elem.in_num, 0, + resp_size) < resp_size) { + return -EINVAL; + } + + req->resp_size = resp_size; + + /* Old BIOSes left some padding by mistake after the req_size/resp_size. + * As a workaround, always consider the first buffer as the virtio-scsi + * request/response, making the payload start at the second element + * of the iovec. + * + * The actual length of the response header, stored in req->resp_size, + * does not change. + * + * TODO: always disable this workaround for virtio 1.0 devices. + */ + if (!virtio_has_feature(vdev, VIRTIO_F_ANY_LAYOUT)) { + if (req->elem.out_num) { + req_size = req->elem.out_sg[0].iov_len; + } + if (req->elem.in_num) { + resp_size = req->elem.in_sg[0].iov_len; + } + } + + out_size = qemu_sgl_concat(req, req->elem.out_sg, + &req->elem.out_addr[0], req->elem.out_num, + req_size); + in_size = qemu_sgl_concat(req, req->elem.in_sg, + &req->elem.in_addr[0], req->elem.in_num, + resp_size); + + if (out_size && in_size) { + return -ENOTSUP; + } + + if (out_size) { + req->mode = SCSI_XFER_TO_DEV; + } else if (in_size) { + req->mode = SCSI_XFER_FROM_DEV; + } + + return 0; +} + +static VirtIOSCSIReq *virtio_scsi_pop_req(VirtIOSCSI *s, VirtQueue *vq) +{ + VirtIOSCSIReq *req = virtio_scsi_init_req(s, vq); + if (!virtqueue_pop(vq, &req->elem)) { + virtio_scsi_free_req(req); + return NULL; + } + return req; +} + +static void virtio_scsi_save_request(QEMUFile *f, SCSIRequest *sreq) +{ + VirtIOSCSIReq *req = sreq->hba_private; + VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(req->dev); + uint32_t n = virtio_queue_get_id(req->vq) - 2; + + assert(n < vs->conf.num_queues); + qemu_put_be32s(f, &n); + qemu_put_buffer(f, (unsigned char *)&req->elem, sizeof(req->elem)); +} + +static void *virtio_scsi_load_request(QEMUFile *f, SCSIRequest *sreq) +{ + SCSIBus *bus = sreq->bus; + VirtIOSCSI *s = container_of(bus, VirtIOSCSI, bus); + VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(s); + VirtIOSCSIReq *req; + uint32_t n; + + qemu_get_be32s(f, &n); + assert(n < vs->conf.num_queues); + req = virtio_scsi_init_req(s, vs->cmd_vqs[n]); + qemu_get_buffer(f, (unsigned char *)&req->elem, sizeof(req->elem)); + /* TODO: add a way for SCSIBusInfo's load_request to fail, + * and fail migration instead of asserting here. + * When we do, we might be able to re-enable NDEBUG below. + */ +#ifdef NDEBUG +#error building with NDEBUG is not supported +#endif + assert(req->elem.in_num <= ARRAY_SIZE(req->elem.in_sg)); + assert(req->elem.out_num <= ARRAY_SIZE(req->elem.out_sg)); + + if (virtio_scsi_parse_req(req, sizeof(VirtIOSCSICmdReq) + vs->cdb_size, + sizeof(VirtIOSCSICmdResp) + vs->sense_size) < 0) { + error_report("invalid SCSI request migration data"); + exit(1); + } + + scsi_req_ref(sreq); + req->sreq = sreq; + if (req->sreq->cmd.mode != SCSI_XFER_NONE) { + assert(req->sreq->cmd.mode == req->mode); + } + return req; +} + +typedef struct { + Notifier notifier; + VirtIOSCSIReq *tmf_req; +} VirtIOSCSICancelNotifier; + +static void virtio_scsi_cancel_notify(Notifier *notifier, void *data) +{ + VirtIOSCSICancelNotifier *n = container_of(notifier, + VirtIOSCSICancelNotifier, + notifier); + + if (--n->tmf_req->remaining == 0) { + virtio_scsi_complete_req(n->tmf_req); + } + g_slice_free(VirtIOSCSICancelNotifier, n); +} + +/* Return 0 if the request is ready to be completed and return to guest; + * -EINPROGRESS if the request is submitted and will be completed later, in the + * case of async cancellation. */ +static int virtio_scsi_do_tmf(VirtIOSCSI *s, VirtIOSCSIReq *req) +{ + SCSIDevice *d = virtio_scsi_device_find(s, req->req.tmf.lun); + SCSIRequest *r, *next; + BusChild *kid; + int target; + int ret = 0; + + if (s->dataplane_started) { + assert(blk_get_aio_context(d->conf.blk) == s->ctx); + } + /* Here VIRTIO_SCSI_S_OK means "FUNCTION COMPLETE". */ + req->resp.tmf.response = VIRTIO_SCSI_S_OK; + + virtio_tswap32s(VIRTIO_DEVICE(s), &req->req.tmf.subtype); + switch (req->req.tmf.subtype) { + case VIRTIO_SCSI_T_TMF_ABORT_TASK: + case VIRTIO_SCSI_T_TMF_QUERY_TASK: + if (!d) { + goto fail; + } + if (d->lun != virtio_scsi_get_lun(req->req.tmf.lun)) { + goto incorrect_lun; + } + QTAILQ_FOREACH_SAFE(r, &d->requests, next, next) { + VirtIOSCSIReq *cmd_req = r->hba_private; + if (cmd_req && cmd_req->req.cmd.tag == req->req.tmf.tag) { + break; + } + } + if (r) { + /* + * Assert that the request has not been completed yet, we + * check for it in the loop above. + */ + assert(r->hba_private); + if (req->req.tmf.subtype == VIRTIO_SCSI_T_TMF_QUERY_TASK) { + /* "If the specified command is present in the task set, then + * return a service response set to FUNCTION SUCCEEDED". + */ + req->resp.tmf.response = VIRTIO_SCSI_S_FUNCTION_SUCCEEDED; + } else { + VirtIOSCSICancelNotifier *notifier; + + req->remaining = 1; + notifier = g_slice_new(VirtIOSCSICancelNotifier); + notifier->tmf_req = req; + notifier->notifier.notify = virtio_scsi_cancel_notify; + scsi_req_cancel_async(r, ¬ifier->notifier); + ret = -EINPROGRESS; + } + } + break; + + case VIRTIO_SCSI_T_TMF_LOGICAL_UNIT_RESET: + if (!d) { + goto fail; + } + if (d->lun != virtio_scsi_get_lun(req->req.tmf.lun)) { + goto incorrect_lun; + } + s->resetting++; + qdev_reset_all(&d->qdev); + s->resetting--; + break; + + case VIRTIO_SCSI_T_TMF_ABORT_TASK_SET: + case VIRTIO_SCSI_T_TMF_CLEAR_TASK_SET: + case VIRTIO_SCSI_T_TMF_QUERY_TASK_SET: + if (!d) { + goto fail; + } + if (d->lun != virtio_scsi_get_lun(req->req.tmf.lun)) { + goto incorrect_lun; + } + + /* Add 1 to "remaining" until virtio_scsi_do_tmf returns. + * This way, if the bus starts calling back to the notifiers + * even before we finish the loop, virtio_scsi_cancel_notify + * will not complete the TMF too early. + */ + req->remaining = 1; + QTAILQ_FOREACH_SAFE(r, &d->requests, next, next) { + if (r->hba_private) { + if (req->req.tmf.subtype == VIRTIO_SCSI_T_TMF_QUERY_TASK_SET) { + /* "If there is any command present in the task set, then + * return a service response set to FUNCTION SUCCEEDED". + */ + req->resp.tmf.response = VIRTIO_SCSI_S_FUNCTION_SUCCEEDED; + break; + } else { + VirtIOSCSICancelNotifier *notifier; + + req->remaining++; + notifier = g_slice_new(VirtIOSCSICancelNotifier); + notifier->notifier.notify = virtio_scsi_cancel_notify; + notifier->tmf_req = req; + scsi_req_cancel_async(r, ¬ifier->notifier); + } + } + } + if (--req->remaining > 0) { + ret = -EINPROGRESS; + } + break; + + case VIRTIO_SCSI_T_TMF_I_T_NEXUS_RESET: + target = req->req.tmf.lun[1]; + s->resetting++; + QTAILQ_FOREACH(kid, &s->bus.qbus.children, sibling) { + d = DO_UPCAST(SCSIDevice, qdev, kid->child); + if (d->channel == 0 && d->id == target) { + qdev_reset_all(&d->qdev); + } + } + s->resetting--; + break; + + case VIRTIO_SCSI_T_TMF_CLEAR_ACA: + default: + req->resp.tmf.response = VIRTIO_SCSI_S_FUNCTION_REJECTED; + break; + } + + return ret; + +incorrect_lun: + req->resp.tmf.response = VIRTIO_SCSI_S_INCORRECT_LUN; + return ret; + +fail: + req->resp.tmf.response = VIRTIO_SCSI_S_BAD_TARGET; + return ret; +} + +void virtio_scsi_handle_ctrl_req(VirtIOSCSI *s, VirtIOSCSIReq *req) +{ + VirtIODevice *vdev = (VirtIODevice *)s; + uint32_t type; + int r = 0; + + if (iov_to_buf(req->elem.out_sg, req->elem.out_num, 0, + &type, sizeof(type)) < sizeof(type)) { + virtio_scsi_bad_req(); + return; + } + + virtio_tswap32s(vdev, &type); + if (type == VIRTIO_SCSI_T_TMF) { + if (virtio_scsi_parse_req(req, sizeof(VirtIOSCSICtrlTMFReq), + sizeof(VirtIOSCSICtrlTMFResp)) < 0) { + virtio_scsi_bad_req(); + } else { + r = virtio_scsi_do_tmf(s, req); + } + + } else if (type == VIRTIO_SCSI_T_AN_QUERY || + type == VIRTIO_SCSI_T_AN_SUBSCRIBE) { + if (virtio_scsi_parse_req(req, sizeof(VirtIOSCSICtrlANReq), + sizeof(VirtIOSCSICtrlANResp)) < 0) { + virtio_scsi_bad_req(); + } else { + req->resp.an.event_actual = 0; + req->resp.an.response = VIRTIO_SCSI_S_OK; + } + } + if (r == 0) { + virtio_scsi_complete_req(req); + } else { + assert(r == -EINPROGRESS); + } +} + +static void virtio_scsi_handle_ctrl(VirtIODevice *vdev, VirtQueue *vq) +{ + VirtIOSCSI *s = (VirtIOSCSI *)vdev; + VirtIOSCSIReq *req; + + if (s->ctx && !s->dataplane_disabled) { + virtio_scsi_dataplane_start(s); + return; + } + while ((req = virtio_scsi_pop_req(s, vq))) { + virtio_scsi_handle_ctrl_req(s, req); + } +} + +static void virtio_scsi_complete_cmd_req(VirtIOSCSIReq *req) +{ + /* Sense data is not in req->resp and is copied separately + * in virtio_scsi_command_complete. + */ + req->resp_size = sizeof(VirtIOSCSICmdResp); + virtio_scsi_complete_req(req); +} + +static void virtio_scsi_command_complete(SCSIRequest *r, uint32_t status, + size_t resid) +{ + VirtIOSCSIReq *req = r->hba_private; + uint8_t sense[SCSI_SENSE_BUF_SIZE]; + uint32_t sense_len; + VirtIODevice *vdev = VIRTIO_DEVICE(req->dev); + + if (r->io_canceled) { + return; + } + + req->resp.cmd.response = VIRTIO_SCSI_S_OK; + req->resp.cmd.status = status; + if (req->resp.cmd.status == GOOD) { + req->resp.cmd.resid = virtio_tswap32(vdev, resid); + } else { + req->resp.cmd.resid = 0; + sense_len = scsi_req_get_sense(r, sense, sizeof(sense)); + sense_len = MIN(sense_len, req->resp_iov.size - sizeof(req->resp.cmd)); + qemu_iovec_from_buf(&req->resp_iov, sizeof(req->resp.cmd), + sense, sense_len); + req->resp.cmd.sense_len = virtio_tswap32(vdev, sense_len); + } + virtio_scsi_complete_cmd_req(req); +} + +static int virtio_scsi_parse_cdb(SCSIDevice *dev, SCSICommand *cmd, + uint8_t *buf, void *hba_private) +{ + VirtIOSCSIReq *req = hba_private; + + if (cmd->len == 0) { + cmd->len = MIN(VIRTIO_SCSI_CDB_DEFAULT_SIZE, SCSI_CMD_BUF_SIZE); + memcpy(cmd->buf, buf, cmd->len); + } + + /* Extract the direction and mode directly from the request, for + * host device passthrough. + */ + cmd->xfer = req->qsgl.size; + cmd->mode = req->mode; + return 0; +} + +static QEMUSGList *virtio_scsi_get_sg_list(SCSIRequest *r) +{ + VirtIOSCSIReq *req = r->hba_private; + + return &req->qsgl; +} + +static void virtio_scsi_request_cancelled(SCSIRequest *r) +{ + VirtIOSCSIReq *req = r->hba_private; + + if (!req) { + return; + } + if (req->dev->resetting) { + req->resp.cmd.response = VIRTIO_SCSI_S_RESET; + } else { + req->resp.cmd.response = VIRTIO_SCSI_S_ABORTED; + } + virtio_scsi_complete_cmd_req(req); +} + +static void virtio_scsi_fail_cmd_req(VirtIOSCSIReq *req) +{ + req->resp.cmd.response = VIRTIO_SCSI_S_FAILURE; + virtio_scsi_complete_cmd_req(req); +} + +bool virtio_scsi_handle_cmd_req_prepare(VirtIOSCSI *s, VirtIOSCSIReq *req) +{ + VirtIOSCSICommon *vs = &s->parent_obj; + SCSIDevice *d; + int rc; + + rc = virtio_scsi_parse_req(req, sizeof(VirtIOSCSICmdReq) + vs->cdb_size, + sizeof(VirtIOSCSICmdResp) + vs->sense_size); + if (rc < 0) { + if (rc == -ENOTSUP) { + virtio_scsi_fail_cmd_req(req); + } else { + virtio_scsi_bad_req(); + } + return false; + } + + d = virtio_scsi_device_find(s, req->req.cmd.lun); + if (!d) { + req->resp.cmd.response = VIRTIO_SCSI_S_BAD_TARGET; + virtio_scsi_complete_cmd_req(req); + return false; + } + if (s->dataplane_started) { + assert(blk_get_aio_context(d->conf.blk) == s->ctx); + } + req->sreq = scsi_req_new(d, req->req.cmd.tag, + virtio_scsi_get_lun(req->req.cmd.lun), + req->req.cmd.cdb, req); + + if (req->sreq->cmd.mode != SCSI_XFER_NONE + && (req->sreq->cmd.mode != req->mode || + req->sreq->cmd.xfer > req->qsgl.size)) { + req->resp.cmd.response = VIRTIO_SCSI_S_OVERRUN; + virtio_scsi_complete_cmd_req(req); + return false; + } + scsi_req_ref(req->sreq); + blk_io_plug(d->conf.blk); + return true; +} + +void virtio_scsi_handle_cmd_req_submit(VirtIOSCSI *s, VirtIOSCSIReq *req) +{ + SCSIRequest *sreq = req->sreq; + if (scsi_req_enqueue(sreq)) { + scsi_req_continue(sreq); + } + blk_io_unplug(sreq->dev->conf.blk); + scsi_req_unref(sreq); +} + +static void virtio_scsi_handle_cmd(VirtIODevice *vdev, VirtQueue *vq) +{ + /* use non-QOM casts in the data path */ + VirtIOSCSI *s = (VirtIOSCSI *)vdev; + VirtIOSCSIReq *req, *next; + QTAILQ_HEAD(, VirtIOSCSIReq) reqs = QTAILQ_HEAD_INITIALIZER(reqs); + + if (s->ctx && !s->dataplane_disabled) { + virtio_scsi_dataplane_start(s); + return; + } + while ((req = virtio_scsi_pop_req(s, vq))) { + if (virtio_scsi_handle_cmd_req_prepare(s, req)) { + QTAILQ_INSERT_TAIL(&reqs, req, next); + } + } + + QTAILQ_FOREACH_SAFE(req, &reqs, next, next) { + virtio_scsi_handle_cmd_req_submit(s, req); + } +} + +static void virtio_scsi_get_config(VirtIODevice *vdev, + uint8_t *config) +{ + VirtIOSCSIConfig *scsiconf = (VirtIOSCSIConfig *)config; + VirtIOSCSICommon *s = VIRTIO_SCSI_COMMON(vdev); + + virtio_stl_p(vdev, &scsiconf->num_queues, s->conf.num_queues); + virtio_stl_p(vdev, &scsiconf->seg_max, 128 - 2); + virtio_stl_p(vdev, &scsiconf->max_sectors, s->conf.max_sectors); + virtio_stl_p(vdev, &scsiconf->cmd_per_lun, s->conf.cmd_per_lun); + virtio_stl_p(vdev, &scsiconf->event_info_size, sizeof(VirtIOSCSIEvent)); + virtio_stl_p(vdev, &scsiconf->sense_size, s->sense_size); + virtio_stl_p(vdev, &scsiconf->cdb_size, s->cdb_size); + virtio_stw_p(vdev, &scsiconf->max_channel, VIRTIO_SCSI_MAX_CHANNEL); + virtio_stw_p(vdev, &scsiconf->max_target, VIRTIO_SCSI_MAX_TARGET); + virtio_stl_p(vdev, &scsiconf->max_lun, VIRTIO_SCSI_MAX_LUN); +} + +static void virtio_scsi_set_config(VirtIODevice *vdev, + const uint8_t *config) +{ + VirtIOSCSIConfig *scsiconf = (VirtIOSCSIConfig *)config; + VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(vdev); + + if ((uint32_t) virtio_ldl_p(vdev, &scsiconf->sense_size) >= 65536 || + (uint32_t) virtio_ldl_p(vdev, &scsiconf->cdb_size) >= 256) { + error_report("bad data written to virtio-scsi configuration space"); + exit(1); + } + + vs->sense_size = virtio_ldl_p(vdev, &scsiconf->sense_size); + vs->cdb_size = virtio_ldl_p(vdev, &scsiconf->cdb_size); +} + +static uint64_t virtio_scsi_get_features(VirtIODevice *vdev, + uint64_t requested_features, + Error **errp) +{ + VirtIOSCSI *s = VIRTIO_SCSI(vdev); + + /* Firstly sync all virtio-scsi possible supported features */ + requested_features |= s->host_features; + return requested_features; +} + +static void virtio_scsi_reset(VirtIODevice *vdev) +{ + VirtIOSCSI *s = VIRTIO_SCSI(vdev); + VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(vdev); + + if (s->ctx) { + virtio_scsi_dataplane_stop(s); + } + s->resetting++; + qbus_reset_all(&s->bus.qbus); + s->resetting--; + + vs->sense_size = VIRTIO_SCSI_SENSE_DEFAULT_SIZE; + vs->cdb_size = VIRTIO_SCSI_CDB_DEFAULT_SIZE; + s->events_dropped = false; +} + +/* The device does not have anything to save beyond the virtio data. + * Request data is saved with callbacks from SCSI devices. + */ +static void virtio_scsi_save(QEMUFile *f, void *opaque) +{ + VirtIODevice *vdev = VIRTIO_DEVICE(opaque); + virtio_save(vdev, f); +} + +static int virtio_scsi_load(QEMUFile *f, void *opaque, int version_id) +{ + VirtIODevice *vdev = VIRTIO_DEVICE(opaque); + int ret; + + ret = virtio_load(vdev, f, version_id); + if (ret) { + return ret; + } + return 0; +} + +void virtio_scsi_push_event(VirtIOSCSI *s, SCSIDevice *dev, + uint32_t event, uint32_t reason) +{ + VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(s); + VirtIOSCSIReq *req; + VirtIOSCSIEvent *evt; + VirtIODevice *vdev = VIRTIO_DEVICE(s); + + if (!(vdev->status & VIRTIO_CONFIG_S_DRIVER_OK)) { + return; + } + + if (s->dataplane_started) { + assert(s->ctx); + aio_context_acquire(s->ctx); + } + + if (s->dataplane_started) { + req = virtio_scsi_pop_req_vring(s, s->event_vring); + } else { + req = virtio_scsi_pop_req(s, vs->event_vq); + } + if (!req) { + s->events_dropped = true; + goto out; + } + + if (s->events_dropped) { + event |= VIRTIO_SCSI_T_EVENTS_MISSED; + s->events_dropped = false; + } + + if (virtio_scsi_parse_req(req, 0, sizeof(VirtIOSCSIEvent))) { + virtio_scsi_bad_req(); + } + + evt = &req->resp.event; + memset(evt, 0, sizeof(VirtIOSCSIEvent)); + evt->event = virtio_tswap32(vdev, event); + evt->reason = virtio_tswap32(vdev, reason); + if (!dev) { + assert(event == VIRTIO_SCSI_T_EVENTS_MISSED); + } else { + evt->lun[0] = 1; + evt->lun[1] = dev->id; + + /* Linux wants us to keep the same encoding we use for REPORT LUNS. */ + if (dev->lun >= 256) { + evt->lun[2] = (dev->lun >> 8) | 0x40; + } + evt->lun[3] = dev->lun & 0xFF; + } + virtio_scsi_complete_req(req); +out: + if (s->dataplane_started) { + aio_context_release(s->ctx); + } +} + +static void virtio_scsi_handle_event(VirtIODevice *vdev, VirtQueue *vq) +{ + VirtIOSCSI *s = VIRTIO_SCSI(vdev); + + if (s->ctx && !s->dataplane_disabled) { + virtio_scsi_dataplane_start(s); + return; + } + if (s->events_dropped) { + virtio_scsi_push_event(s, NULL, VIRTIO_SCSI_T_NO_EVENT, 0); + } +} + +static void virtio_scsi_change(SCSIBus *bus, SCSIDevice *dev, SCSISense sense) +{ + VirtIOSCSI *s = container_of(bus, VirtIOSCSI, bus); + VirtIODevice *vdev = VIRTIO_DEVICE(s); + + if (virtio_has_feature(vdev, VIRTIO_SCSI_F_CHANGE) && + dev->type != TYPE_ROM) { + virtio_scsi_push_event(s, dev, VIRTIO_SCSI_T_PARAM_CHANGE, + sense.asc | (sense.ascq << 8)); + } +} + +static void virtio_scsi_hotplug(HotplugHandler *hotplug_dev, DeviceState *dev, + Error **errp) +{ + VirtIODevice *vdev = VIRTIO_DEVICE(hotplug_dev); + VirtIOSCSI *s = VIRTIO_SCSI(vdev); + SCSIDevice *sd = SCSI_DEVICE(dev); + + if (s->ctx && !s->dataplane_disabled) { + if (blk_op_is_blocked(sd->conf.blk, BLOCK_OP_TYPE_DATAPLANE, errp)) { + return; + } + blk_op_block_all(sd->conf.blk, s->blocker); + aio_context_acquire(s->ctx); + blk_set_aio_context(sd->conf.blk, s->ctx); + aio_context_release(s->ctx); + } + + if (virtio_has_feature(vdev, VIRTIO_SCSI_F_HOTPLUG)) { + virtio_scsi_push_event(s, sd, + VIRTIO_SCSI_T_TRANSPORT_RESET, + VIRTIO_SCSI_EVT_RESET_RESCAN); + } +} + +static void virtio_scsi_hotunplug(HotplugHandler *hotplug_dev, DeviceState *dev, + Error **errp) +{ + VirtIODevice *vdev = VIRTIO_DEVICE(hotplug_dev); + VirtIOSCSI *s = VIRTIO_SCSI(vdev); + SCSIDevice *sd = SCSI_DEVICE(dev); + + if (virtio_has_feature(vdev, VIRTIO_SCSI_F_HOTPLUG)) { + virtio_scsi_push_event(s, sd, + VIRTIO_SCSI_T_TRANSPORT_RESET, + VIRTIO_SCSI_EVT_RESET_REMOVED); + } + + if (s->ctx) { + blk_op_unblock_all(sd->conf.blk, s->blocker); + } + qdev_simple_device_unplug_cb(hotplug_dev, dev, errp); +} + +static struct SCSIBusInfo virtio_scsi_scsi_info = { + .tcq = true, + .max_channel = VIRTIO_SCSI_MAX_CHANNEL, + .max_target = VIRTIO_SCSI_MAX_TARGET, + .max_lun = VIRTIO_SCSI_MAX_LUN, + + .complete = virtio_scsi_command_complete, + .cancel = virtio_scsi_request_cancelled, + .change = virtio_scsi_change, + .parse_cdb = virtio_scsi_parse_cdb, + .get_sg_list = virtio_scsi_get_sg_list, + .save_request = virtio_scsi_save_request, + .load_request = virtio_scsi_load_request, +}; + +void virtio_scsi_common_realize(DeviceState *dev, Error **errp, + HandleOutput ctrl, HandleOutput evt, + HandleOutput cmd) +{ + VirtIODevice *vdev = VIRTIO_DEVICE(dev); + VirtIOSCSICommon *s = VIRTIO_SCSI_COMMON(dev); + int i; + + virtio_init(vdev, "virtio-scsi", VIRTIO_ID_SCSI, + sizeof(VirtIOSCSIConfig)); + + if (s->conf.num_queues == 0 || + s->conf.num_queues > VIRTIO_QUEUE_MAX - 2) { + error_setg(errp, "Invalid number of queues (= %" PRIu32 "), " + "must be a positive integer less than %d.", + s->conf.num_queues, VIRTIO_QUEUE_MAX - 2); + virtio_cleanup(vdev); + return; + } + s->cmd_vqs = g_new0(VirtQueue *, s->conf.num_queues); + s->sense_size = VIRTIO_SCSI_SENSE_DEFAULT_SIZE; + s->cdb_size = VIRTIO_SCSI_CDB_DEFAULT_SIZE; + + s->ctrl_vq = virtio_add_queue(vdev, VIRTIO_SCSI_VQ_SIZE, + ctrl); + s->event_vq = virtio_add_queue(vdev, VIRTIO_SCSI_VQ_SIZE, + evt); + for (i = 0; i < s->conf.num_queues; i++) { + s->cmd_vqs[i] = virtio_add_queue(vdev, VIRTIO_SCSI_VQ_SIZE, + cmd); + } + + if (s->conf.iothread) { + virtio_scsi_set_iothread(VIRTIO_SCSI(s), s->conf.iothread); + } +} + +/* Disable dataplane thread during live migration since it does not + * update the dirty memory bitmap yet. + */ +static void virtio_scsi_migration_state_changed(Notifier *notifier, void *data) +{ + VirtIOSCSI *s = container_of(notifier, VirtIOSCSI, + migration_state_notifier); + MigrationState *mig = data; + + if (migration_in_setup(mig)) { + if (!s->dataplane_started) { + return; + } + virtio_scsi_dataplane_stop(s); + s->dataplane_disabled = true; + } else if (migration_has_finished(mig) || + migration_has_failed(mig)) { + if (s->dataplane_started) { + return; + } + blk_drain_all(); /* complete in-flight non-dataplane requests */ + s->dataplane_disabled = false; + } +} + +static void virtio_scsi_device_realize(DeviceState *dev, Error **errp) +{ + VirtIODevice *vdev = VIRTIO_DEVICE(dev); + VirtIOSCSI *s = VIRTIO_SCSI(dev); + static int virtio_scsi_id; + Error *err = NULL; + + virtio_scsi_common_realize(dev, &err, virtio_scsi_handle_ctrl, + virtio_scsi_handle_event, + virtio_scsi_handle_cmd); + if (err != NULL) { + error_propagate(errp, err); + return; + } + + scsi_bus_new(&s->bus, sizeof(s->bus), dev, + &virtio_scsi_scsi_info, vdev->bus_name); + /* override default SCSI bus hotplug-handler, with virtio-scsi's one */ + qbus_set_hotplug_handler(BUS(&s->bus), dev, &error_abort); + + if (!dev->hotplugged) { + scsi_bus_legacy_handle_cmdline(&s->bus, &err); + if (err != NULL) { + error_propagate(errp, err); + return; + } + } + + register_savevm(dev, "virtio-scsi", virtio_scsi_id++, 1, + virtio_scsi_save, virtio_scsi_load, s); + s->migration_state_notifier.notify = virtio_scsi_migration_state_changed; + add_migration_state_change_notifier(&s->migration_state_notifier); + + error_setg(&s->blocker, "block device is in use by data plane"); +} + +static void virtio_scsi_instance_init(Object *obj) +{ + VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(obj); + + object_property_add_link(obj, "iothread", TYPE_IOTHREAD, + (Object **)&vs->conf.iothread, + qdev_prop_allow_set_link_before_realize, + OBJ_PROP_LINK_UNREF_ON_RELEASE, &error_abort); +} + +void virtio_scsi_common_unrealize(DeviceState *dev, Error **errp) +{ + VirtIODevice *vdev = VIRTIO_DEVICE(dev); + VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); + + g_free(vs->cmd_vqs); + virtio_cleanup(vdev); +} + +static void virtio_scsi_device_unrealize(DeviceState *dev, Error **errp) +{ + VirtIOSCSI *s = VIRTIO_SCSI(dev); + + error_free(s->blocker); + + unregister_savevm(dev, "virtio-scsi", s); + remove_migration_state_change_notifier(&s->migration_state_notifier); + + virtio_scsi_common_unrealize(dev, errp); +} + +static Property virtio_scsi_properties[] = { + DEFINE_PROP_UINT32("num_queues", VirtIOSCSI, parent_obj.conf.num_queues, 1), + DEFINE_PROP_UINT32("max_sectors", VirtIOSCSI, parent_obj.conf.max_sectors, + 0xFFFF), + DEFINE_PROP_UINT32("cmd_per_lun", VirtIOSCSI, parent_obj.conf.cmd_per_lun, + 128), + DEFINE_PROP_BIT("hotplug", VirtIOSCSI, host_features, + VIRTIO_SCSI_F_HOTPLUG, true), + DEFINE_PROP_BIT("param_change", VirtIOSCSI, host_features, + VIRTIO_SCSI_F_CHANGE, true), + DEFINE_PROP_END_OF_LIST(), +}; + +static void virtio_scsi_common_class_init(ObjectClass *klass, void *data) +{ + VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass); + DeviceClass *dc = DEVICE_CLASS(klass); + + vdc->get_config = virtio_scsi_get_config; + set_bit(DEVICE_CATEGORY_STORAGE, dc->categories); +} + +static void virtio_scsi_class_init(ObjectClass *klass, void *data) +{ + DeviceClass *dc = DEVICE_CLASS(klass); + VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass); + HotplugHandlerClass *hc = HOTPLUG_HANDLER_CLASS(klass); + + dc->props = virtio_scsi_properties; + set_bit(DEVICE_CATEGORY_STORAGE, dc->categories); + vdc->realize = virtio_scsi_device_realize; + vdc->unrealize = virtio_scsi_device_unrealize; + vdc->set_config = virtio_scsi_set_config; + vdc->get_features = virtio_scsi_get_features; + vdc->reset = virtio_scsi_reset; + hc->plug = virtio_scsi_hotplug; + hc->unplug = virtio_scsi_hotunplug; +} + +static const TypeInfo virtio_scsi_common_info = { + .name = TYPE_VIRTIO_SCSI_COMMON, + .parent = TYPE_VIRTIO_DEVICE, + .instance_size = sizeof(VirtIOSCSICommon), + .abstract = true, + .class_init = virtio_scsi_common_class_init, +}; + +static const TypeInfo virtio_scsi_info = { + .name = TYPE_VIRTIO_SCSI, + .parent = TYPE_VIRTIO_SCSI_COMMON, + .instance_size = sizeof(VirtIOSCSI), + .instance_init = virtio_scsi_instance_init, + .class_init = virtio_scsi_class_init, + .interfaces = (InterfaceInfo[]) { + { TYPE_HOTPLUG_HANDLER }, + { } + } +}; + +static void virtio_register_types(void) +{ + type_register_static(&virtio_scsi_common_info); + type_register_static(&virtio_scsi_info); +} + +type_init(virtio_register_types) |