/* * Virtio SCSI HBA * * Copyright IBM, Corp. 2010 * Copyright Red Hat, Inc. 2011 * * Authors: * Stefan Hajnoczi * Paolo Bonzini * * 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 "qemu/osdep.h" #include "qapi/error.h" #include "standard-headers/linux/virtio_ids.h" #include "hw/virtio/virtio-scsi.h" #include "migration/qemu-file-types.h" #include "qemu/defer-call.h" #include "qemu/error-report.h" #include "qemu/iov.h" #include "qemu/module.h" #include "sysemu/block-backend.h" #include "sysemu/dma.h" #include "hw/qdev-properties.h" #include "hw/scsi/scsi.h" #include "scsi/constants.h" #include "hw/virtio/virtio-bus.h" #include "hw/virtio/virtio-access.h" #include "trace.h" typedef struct VirtIOSCSIReq { /* * Note: * - fields up to resp_iov are initialized by virtio_scsi_init_req; * - fields starting at vring are zeroed by virtio_scsi_init_req. */ VirtQueueElement elem; VirtIOSCSI *dev; VirtQueue *vq; QEMUSGList qsgl; QEMUIOVector resp_iov; /* Used for two-stage request submission and TMFs deferred to BH */ QTAILQ_ENTRY(VirtIOSCSIReq) next; /* Used for cancellation of request during TMFs */ int remaining; SCSIRequest *sreq; size_t resp_size; enum SCSIXferMode mode; union { VirtIOSCSICmdResp cmd; VirtIOSCSICtrlTMFResp tmf; VirtIOSCSICtrlANResp an; VirtIOSCSIEvent event; } resp; union { VirtIOSCSICmdReq cmd; VirtIOSCSICtrlTMFReq tmf; VirtIOSCSICtrlANReq an; } req; } VirtIOSCSIReq; static inline int virtio_scsi_get_lun(uint8_t *lun) { return ((lun[2] << 8) | lun[3]) & 0x3FFF; } static inline SCSIDevice *virtio_scsi_device_get(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_get(&s->bus, 0, lun[1], virtio_scsi_get_lun(lun)); } static void virtio_scsi_init_req(VirtIOSCSI *s, VirtQueue *vq, VirtIOSCSIReq *req) { VirtIODevice *vdev = VIRTIO_DEVICE(s); const size_t zero_skip = offsetof(VirtIOSCSIReq, resp_iov) + sizeof(req->resp_iov); req->vq = vq; req->dev = s; qemu_sglist_init(&req->qsgl, DEVICE(s), 8, vdev->dma_as); qemu_iovec_init(&req->resp_iov, 1); memset((uint8_t *)req + zero_skip, 0, sizeof(*req) - zero_skip); } static void virtio_scsi_free_req(VirtIOSCSIReq *req) { qemu_iovec_destroy(&req->resp_iov); qemu_sglist_destroy(&req->qsgl); g_free(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); virtqueue_push(vq, &req->elem, req->qsgl.size + req->resp_iov.size); if (s->dataplane_started && !s->dataplane_fenced) { virtio_notify_irqfd(vdev, vq); } else { 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_complete_req_bh(void *opaque) { VirtIOSCSIReq *req = opaque; virtio_scsi_complete_req(req); } /* * Called from virtio_scsi_do_one_tmf_bh() in main loop thread. The main loop * thread cannot touch the virtqueue since that could race with an IOThread. */ static void virtio_scsi_complete_req_from_main_loop(VirtIOSCSIReq *req) { VirtIOSCSI *s = req->dev; if (!s->ctx || s->ctx == qemu_get_aio_context()) { /* No need to schedule a BH when there is no IOThread */ virtio_scsi_complete_req(req); } else { /* Run request completion in the IOThread */ aio_wait_bh_oneshot(s->ctx, virtio_scsi_complete_req_bh, req); } } static void virtio_scsi_bad_req(VirtIOSCSIReq *req) { virtio_error(VIRTIO_DEVICE(req->dev), "wrong size for virtio-scsi headers"); virtqueue_detach_element(req->vq, &req->elem, 0); virtio_scsi_free_req(req); } 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_vdev_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) { VirtIOSCSICommon *vs = (VirtIOSCSICommon *)s; VirtIOSCSIReq *req; req = virtqueue_pop(vq, sizeof(VirtIOSCSIReq) + vs->cdb_size); if (!req) { return NULL; } virtio_scsi_init_req(s, vq, req); return req; } static void virtio_scsi_save_request(QEMUFile *f, SCSIRequest *sreq) { VirtIOSCSIReq *req = sreq->hba_private; VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(req->dev); VirtIODevice *vdev = VIRTIO_DEVICE(req->dev); uint32_t n = virtio_get_queue_index(req->vq) - VIRTIO_SCSI_VQ_NUM_FIXED; assert(n < vs->conf.num_queues); qemu_put_be32s(f, &n); qemu_put_virtqueue_element(vdev, f, &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); VirtIODevice *vdev = VIRTIO_DEVICE(s); VirtIOSCSIReq *req; uint32_t n; qemu_get_be32s(f, &n); assert(n < vs->conf.num_queues); req = qemu_get_virtqueue_element(vdev, f, sizeof(VirtIOSCSIReq) + vs->cdb_size); virtio_scsi_init_req(s, vs->cmd_vqs[n], req); 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) { VirtIOSCSIReq *req = n->tmf_req; trace_virtio_scsi_tmf_resp(virtio_scsi_get_lun(req->req.tmf.lun), req->req.tmf.tag, req->resp.tmf.response); virtio_scsi_complete_req(req); } g_free(n); } static inline void virtio_scsi_ctx_check(VirtIOSCSI *s, SCSIDevice *d) { if (s->dataplane_started && d && blk_is_available(d->conf.blk)) { assert(blk_get_aio_context(d->conf.blk) == s->ctx); } } static void virtio_scsi_do_one_tmf_bh(VirtIOSCSIReq *req) { VirtIOSCSI *s = req->dev; SCSIDevice *d = virtio_scsi_device_get(s, req->req.tmf.lun); BusChild *kid; int target; switch (req->req.tmf.subtype) { case VIRTIO_SCSI_T_TMF_LOGICAL_UNIT_RESET: if (!d) { req->resp.tmf.response = VIRTIO_SCSI_S_BAD_TARGET; goto out; } if (d->lun != virtio_scsi_get_lun(req->req.tmf.lun)) { req->resp.tmf.response = VIRTIO_SCSI_S_INCORRECT_LUN; goto out; } qatomic_inc(&s->resetting); device_cold_reset(&d->qdev); qatomic_dec(&s->resetting); break; case VIRTIO_SCSI_T_TMF_I_T_NEXUS_RESET: target = req->req.tmf.lun[1]; qatomic_inc(&s->resetting); rcu_read_lock(); QTAILQ_FOREACH_RCU(kid, &s->bus.qbus.children, sibling) { SCSIDevice *d1 = SCSI_DEVICE(kid->child); if (d1->channel == 0 && d1->id == target) { device_cold_reset(&d1->qdev); } } rcu_read_unlock(); qatomic_dec(&s->resetting); break; default: g_assert_not_reached(); } out: object_unref(OBJECT(d)); virtio_scsi_complete_req_from_main_loop(req); } /* Some TMFs must be processed from the main loop thread */ static void virtio_scsi_do_tmf_bh(void *opaque) { VirtIOSCSI *s = opaque; QTAILQ_HEAD(, VirtIOSCSIReq) reqs = QTAILQ_HEAD_INITIALIZER(reqs); VirtIOSCSIReq *req; VirtIOSCSIReq *tmp; GLOBAL_STATE_CODE(); WITH_QEMU_LOCK_GUARD(&s->tmf_bh_lock) { QTAILQ_FOREACH_SAFE(req, &s->tmf_bh_list, next, tmp) { QTAILQ_REMOVE(&s->tmf_bh_list, req, next); QTAILQ_INSERT_TAIL(&reqs, req, next); } qemu_bh_delete(s->tmf_bh); s->tmf_bh = NULL; } QTAILQ_FOREACH_SAFE(req, &reqs, next, tmp) { QTAILQ_REMOVE(&reqs, req, next); virtio_scsi_do_one_tmf_bh(req); } } static void virtio_scsi_reset_tmf_bh(VirtIOSCSI *s) { VirtIOSCSIReq *req; VirtIOSCSIReq *tmp; GLOBAL_STATE_CODE(); /* Called after ioeventfd has been stopped, so tmf_bh_lock is not needed */ if (s->tmf_bh) { qemu_bh_delete(s->tmf_bh); s->tmf_bh = NULL; } QTAILQ_FOREACH_SAFE(req, &s->tmf_bh_list, next, tmp) { QTAILQ_REMOVE(&s->tmf_bh_list, req, next); /* SAM-6 6.3.2 Hard reset */ req->resp.tmf.response = VIRTIO_SCSI_S_TARGET_FAILURE; virtio_scsi_complete_req(req); } } static void virtio_scsi_defer_tmf_to_bh(VirtIOSCSIReq *req) { VirtIOSCSI *s = req->dev; WITH_QEMU_LOCK_GUARD(&s->tmf_bh_lock) { QTAILQ_INSERT_TAIL(&s->tmf_bh_list, req, next); if (!s->tmf_bh) { s->tmf_bh = qemu_bh_new(virtio_scsi_do_tmf_bh, s); qemu_bh_schedule(s->tmf_bh); } } } /* 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_get(s, req->req.tmf.lun); SCSIRequest *r, *next; int ret = 0; virtio_scsi_ctx_check(s, d); /* Here VIRTIO_SCSI_S_OK means "FUNCTION COMPLETE". */ req->resp.tmf.response = VIRTIO_SCSI_S_OK; /* * req->req.tmf has the QEMU_PACKED attribute. Don't use virtio_tswap32s() * to avoid compiler errors. */ req->req.tmf.subtype = virtio_tswap32(VIRTIO_DEVICE(s), req->req.tmf.subtype); trace_virtio_scsi_tmf_req(virtio_scsi_get_lun(req->req.tmf.lun), req->req.tmf.tag, 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_new(VirtIOSCSICancelNotifier, 1); 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: case VIRTIO_SCSI_T_TMF_I_T_NEXUS_RESET: virtio_scsi_defer_tmf_to_bh(req); ret = -EINPROGRESS; 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_new(VirtIOSCSICancelNotifier, 1); 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_CLEAR_ACA: default: req->resp.tmf.response = VIRTIO_SCSI_S_FUNCTION_REJECTED; break; } object_unref(OBJECT(d)); return ret; incorrect_lun: req->resp.tmf.response = VIRTIO_SCSI_S_INCORRECT_LUN; object_unref(OBJECT(d)); return ret; fail: req->resp.tmf.response = VIRTIO_SCSI_S_BAD_TARGET; object_unref(OBJECT(d)); return ret; } static 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(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(req); return; } 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(req); return; } else { req->req.an.event_requested = virtio_tswap32(VIRTIO_DEVICE(s), req->req.an.event_requested); trace_virtio_scsi_an_req(virtio_scsi_get_lun(req->req.an.lun), req->req.an.event_requested); req->resp.an.event_actual = 0; req->resp.an.response = VIRTIO_SCSI_S_OK; } } if (r == 0) { if (type == VIRTIO_SCSI_T_TMF) trace_virtio_scsi_tmf_resp(virtio_scsi_get_lun(req->req.tmf.lun), req->req.tmf.tag, req->resp.tmf.response); else if (type == VIRTIO_SCSI_T_AN_QUERY || type == VIRTIO_SCSI_T_AN_SUBSCRIBE) trace_virtio_scsi_an_resp(virtio_scsi_get_lun(req->req.an.lun), req->resp.an.response); virtio_scsi_complete_req(req); } else { assert(r == -EINPROGRESS); } } static void virtio_scsi_handle_ctrl_vq(VirtIOSCSI *s, VirtQueue *vq) { VirtIOSCSIReq *req; while ((req = virtio_scsi_pop_req(s, vq))) { virtio_scsi_handle_ctrl_req(s, req); } } /* * If dataplane is configured but not yet started, do so now and return true on * success. * * Dataplane is started by the core virtio code but virtqueue handler functions * can also be invoked when a guest kicks before DRIVER_OK, so this helper * function helps us deal with manually starting ioeventfd in that case. */ static bool virtio_scsi_defer_to_dataplane(VirtIOSCSI *s) { if (!s->ctx || s->dataplane_started) { return false; } virtio_device_start_ioeventfd(&s->parent_obj.parent_obj); return !s->dataplane_fenced; } static void virtio_scsi_handle_ctrl(VirtIODevice *vdev, VirtQueue *vq) { VirtIOSCSI *s = (VirtIOSCSI *)vdev; if (virtio_scsi_defer_to_dataplane(s)) { return; } virtio_scsi_handle_ctrl_vq(s, vq); } static void virtio_scsi_complete_cmd_req(VirtIOSCSIReq *req) { trace_virtio_scsi_cmd_resp(virtio_scsi_get_lun(req->req.cmd.lun), req->req.cmd.tag, req->resp.cmd.response, req->resp.cmd.status); /* 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_failed(SCSIRequest *r) { VirtIOSCSIReq *req = r->hba_private; if (r->io_canceled) { return; } req->resp.cmd.status = GOOD; switch (r->host_status) { case SCSI_HOST_NO_LUN: req->resp.cmd.response = VIRTIO_SCSI_S_INCORRECT_LUN; break; case SCSI_HOST_BUSY: req->resp.cmd.response = VIRTIO_SCSI_S_BUSY; break; case SCSI_HOST_TIME_OUT: case SCSI_HOST_ABORTED: req->resp.cmd.response = VIRTIO_SCSI_S_ABORTED; break; case SCSI_HOST_BAD_RESPONSE: req->resp.cmd.response = VIRTIO_SCSI_S_BAD_TARGET; break; case SCSI_HOST_RESET: req->resp.cmd.response = VIRTIO_SCSI_S_RESET; break; case SCSI_HOST_TRANSPORT_DISRUPTED: req->resp.cmd.response = VIRTIO_SCSI_S_TRANSPORT_FAILURE; break; case SCSI_HOST_TARGET_FAILURE: req->resp.cmd.response = VIRTIO_SCSI_S_TARGET_FAILURE; break; case SCSI_HOST_RESERVATION_ERROR: req->resp.cmd.response = VIRTIO_SCSI_S_NEXUS_FAILURE; break; case SCSI_HOST_ALLOCATION_FAILURE: case SCSI_HOST_MEDIUM_ERROR: case SCSI_HOST_ERROR: default: req->resp.cmd.response = VIRTIO_SCSI_S_FAILURE; break; } virtio_scsi_complete_cmd_req(req); } static void virtio_scsi_command_complete(SCSIRequest *r, 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 = r->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, size_t buf_len, 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 (qatomic_read(&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); } static int virtio_scsi_handle_cmd_req_prepare(VirtIOSCSI *s, VirtIOSCSIReq *req) { VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(s); 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); return -ENOTSUP; } else { virtio_scsi_bad_req(req); return -EINVAL; } } trace_virtio_scsi_cmd_req(virtio_scsi_get_lun(req->req.cmd.lun), req->req.cmd.tag, req->req.cmd.cdb[0]); d = virtio_scsi_device_get(s, req->req.cmd.lun); if (!d) { req->resp.cmd.response = VIRTIO_SCSI_S_BAD_TARGET; virtio_scsi_complete_cmd_req(req); return -ENOENT; } virtio_scsi_ctx_check(s, d); req->sreq = scsi_req_new(d, req->req.cmd.tag, virtio_scsi_get_lun(req->req.cmd.lun), req->req.cmd.cdb, vs->cdb_size, 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); object_unref(OBJECT(d)); return -ENOBUFS; } scsi_req_ref(req->sreq); defer_call_begin(); object_unref(OBJECT(d)); return 0; } static void virtio_scsi_handle_cmd_req_submit(VirtIOSCSI *s, VirtIOSCSIReq *req) { SCSIRequest *sreq = req->sreq; if (scsi_req_enqueue(sreq)) { scsi_req_continue(sreq); } defer_call_end(); scsi_req_unref(sreq); } static void virtio_scsi_handle_cmd_vq(VirtIOSCSI *s, VirtQueue *vq) { VirtIOSCSIReq *req, *next; int ret = 0; bool suppress_notifications = virtio_queue_get_notification(vq); QTAILQ_HEAD(, VirtIOSCSIReq) reqs = QTAILQ_HEAD_INITIALIZER(reqs); do { if (suppress_notifications) { virtio_queue_set_notification(vq, 0); } while ((req = virtio_scsi_pop_req(s, vq))) { ret = virtio_scsi_handle_cmd_req_prepare(s, req); if (!ret) { QTAILQ_INSERT_TAIL(&reqs, req, next); } else if (ret == -EINVAL) { /* The device is broken and shouldn't process any request */ while (!QTAILQ_EMPTY(&reqs)) { req = QTAILQ_FIRST(&reqs); QTAILQ_REMOVE(&reqs, req, next); defer_call_end(); scsi_req_unref(req->sreq); virtqueue_detach_element(req->vq, &req->elem, 0); virtio_scsi_free_req(req); } } } if (suppress_notifications) { virtio_queue_set_notification(vq, 1); } } while (ret != -EINVAL && !virtio_queue_empty(vq)); QTAILQ_FOREACH_SAFE(req, &reqs, next, next) { virtio_scsi_handle_cmd_req_submit(s, req); } } static void virtio_scsi_handle_cmd(VirtIODevice *vdev, VirtQueue *vq) { /* use non-QOM casts in the data path */ VirtIOSCSI *s = (VirtIOSCSI *)vdev; if (virtio_scsi_defer_to_dataplane(s)) { return; } virtio_scsi_handle_cmd_vq(s, vq); } 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, s->conf.seg_max_adjust ? s->conf.virtqueue_size - 2 : 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) { virtio_error(vdev, "bad data written to virtio-scsi configuration space"); return; } 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); assert(!s->dataplane_started); virtio_scsi_reset_tmf_bh(s); qatomic_inc(&s->resetting); bus_cold_reset(BUS(&s->bus)); qatomic_dec(&s->resetting); vs->sense_size = VIRTIO_SCSI_SENSE_DEFAULT_SIZE; vs->cdb_size = VIRTIO_SCSI_CDB_DEFAULT_SIZE; s->events_dropped = false; } typedef struct { uint32_t event; uint32_t reason; union { /* Used by messages specific to a device */ struct { uint32_t id; uint32_t lun; } address; }; } VirtIOSCSIEventInfo; static void virtio_scsi_push_event(VirtIOSCSI *s, const VirtIOSCSIEventInfo *info) { VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(s); VirtIOSCSIReq *req; VirtIOSCSIEvent *evt; VirtIODevice *vdev = VIRTIO_DEVICE(s); uint32_t event = info->event; uint32_t reason = info->reason; if (!(vdev->status & VIRTIO_CONFIG_S_DRIVER_OK)) { return; } req = virtio_scsi_pop_req(s, vs->event_vq); if (!req) { s->events_dropped = true; return; } 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(req); return; } evt = &req->resp.event; memset(evt, 0, sizeof(VirtIOSCSIEvent)); evt->event = virtio_tswap32(vdev, event); evt->reason = virtio_tswap32(vdev, reason); if (event != VIRTIO_SCSI_T_EVENTS_MISSED) { evt->lun[0] = 1; evt->lun[1] = info->address.id; /* Linux wants us to keep the same encoding we use for REPORT LUNS. */ if (info->address.lun >= 256) { evt->lun[2] = (info->address.lun >> 8) | 0x40; } evt->lun[3] = info->address.lun & 0xFF; } trace_virtio_scsi_event(virtio_scsi_get_lun(evt->lun), event, reason); virtio_scsi_complete_req(req); } static void virtio_scsi_handle_event_vq(VirtIOSCSI *s, VirtQueue *vq) { if (s->events_dropped) { VirtIOSCSIEventInfo info = { .event = VIRTIO_SCSI_T_NO_EVENT, }; virtio_scsi_push_event(s, &info); } } static void virtio_scsi_handle_event(VirtIODevice *vdev, VirtQueue *vq) { VirtIOSCSI *s = VIRTIO_SCSI(vdev); if (virtio_scsi_defer_to_dataplane(s)) { return; } virtio_scsi_handle_event_vq(s, vq); } 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_vdev_has_feature(vdev, VIRTIO_SCSI_F_CHANGE) && dev->type != TYPE_ROM) { VirtIOSCSIEventInfo info = { .event = VIRTIO_SCSI_T_PARAM_CHANGE, .reason = sense.asc | (sense.ascq << 8), .address = { .id = dev->id, .lun = dev->lun, }, }; virtio_scsi_push_event(s, &info); } } static void virtio_scsi_pre_hotplug(HotplugHandler *hotplug_dev, DeviceState *dev, Error **errp) { SCSIDevice *sd = SCSI_DEVICE(dev); sd->hba_supports_iothread = true; } 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); int ret; if (s->ctx && !s->dataplane_fenced) { if (blk_op_is_blocked(sd->conf.blk, BLOCK_OP_TYPE_DATAPLANE, errp)) { return; } ret = blk_set_aio_context(sd->conf.blk, s->ctx, errp); if (ret < 0) { return; } } if (virtio_vdev_has_feature(vdev, VIRTIO_SCSI_F_HOTPLUG)) { VirtIOSCSIEventInfo info = { .event = VIRTIO_SCSI_T_TRANSPORT_RESET, .reason = VIRTIO_SCSI_EVT_RESET_RESCAN, .address = { .id = sd->id, .lun = sd->lun, }, }; virtio_scsi_push_event(s, &info); scsi_bus_set_ua(&s->bus, SENSE_CODE(REPORTED_LUNS_CHANGED)); } } 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); VirtIOSCSIEventInfo info = { .event = VIRTIO_SCSI_T_TRANSPORT_RESET, .reason = VIRTIO_SCSI_EVT_RESET_REMOVED, .address = { .id = sd->id, .lun = sd->lun, }, }; qdev_simple_device_unplug_cb(hotplug_dev, dev, errp); if (s->ctx) { /* If other users keep the BlockBackend in the iothread, that's ok */ blk_set_aio_context(sd->conf.blk, qemu_get_aio_context(), NULL); } if (virtio_vdev_has_feature(vdev, VIRTIO_SCSI_F_HOTPLUG)) { virtio_scsi_push_event(s, &info); scsi_bus_set_ua(&s->bus, SENSE_CODE(REPORTED_LUNS_CHANGED)); } } /* Suspend virtqueue ioeventfd processing during drain */ static void virtio_scsi_drained_begin(SCSIBus *bus) { VirtIOSCSI *s = container_of(bus, VirtIOSCSI, bus); VirtIODevice *vdev = VIRTIO_DEVICE(s); uint32_t total_queues = VIRTIO_SCSI_VQ_NUM_FIXED + s->parent_obj.conf.num_queues; /* * Drain is called when stopping dataplane but the host notifier has * already been detached. Detaching multiple times is a no-op if nothing * else is using the monitoring same file descriptor, but avoid it just in * case. * * Also, don't detach if dataplane has not even been started yet because * the host notifier isn't attached. */ if (s->dataplane_stopping || !s->dataplane_started) { return; } for (uint32_t i = 0; i < total_queues; i++) { VirtQueue *vq = virtio_get_queue(vdev, i); virtio_queue_aio_detach_host_notifier(vq, s->ctx); } } /* Resume virtqueue ioeventfd processing after drain */ static void virtio_scsi_drained_end(SCSIBus *bus) { VirtIOSCSI *s = container_of(bus, VirtIOSCSI, bus); VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(s); VirtIODevice *vdev = VIRTIO_DEVICE(s); uint32_t total_queues = VIRTIO_SCSI_VQ_NUM_FIXED + s->parent_obj.conf.num_queues; /* * Drain is called when stopping dataplane. Keep the host notifier detached * so it's not left dangling after dataplane is stopped. * * Also, don't attach if dataplane has not even been started yet. We're not * ready. */ if (s->dataplane_stopping || !s->dataplane_started) { return; } for (uint32_t i = 0; i < total_queues; i++) { VirtQueue *vq = virtio_get_queue(vdev, i); if (vq == vs->event_vq) { virtio_queue_aio_attach_host_notifier_no_poll(vq, s->ctx); } else { virtio_queue_aio_attach_host_notifier(vq, s->ctx); } } } 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, .fail = virtio_scsi_command_failed, .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, .drained_begin = virtio_scsi_drained_begin, .drained_end = virtio_scsi_drained_end, }; void virtio_scsi_common_realize(DeviceState *dev, VirtIOHandleOutput ctrl, VirtIOHandleOutput evt, VirtIOHandleOutput cmd, Error **errp) { VirtIODevice *vdev = VIRTIO_DEVICE(dev); VirtIOSCSICommon *s = VIRTIO_SCSI_COMMON(dev); int i; virtio_init(vdev, VIRTIO_ID_SCSI, sizeof(VirtIOSCSIConfig)); if (s->conf.num_queues == VIRTIO_SCSI_AUTO_NUM_QUEUES) { s->conf.num_queues = 1; } if (s->conf.num_queues == 0 || s->conf.num_queues > VIRTIO_QUEUE_MAX - VIRTIO_SCSI_VQ_NUM_FIXED) { error_setg(errp, "Invalid number of queues (= %" PRIu32 "), " "must be a positive integer less than %d.", s->conf.num_queues, VIRTIO_QUEUE_MAX - VIRTIO_SCSI_VQ_NUM_FIXED); virtio_cleanup(vdev); return; } if (s->conf.virtqueue_size <= 2) { error_setg(errp, "invalid virtqueue_size property (= %" PRIu32 "), " "must be > 2", s->conf.virtqueue_size); 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, s->conf.virtqueue_size, ctrl); s->event_vq = virtio_add_queue(vdev, s->conf.virtqueue_size, evt); for (i = 0; i < s->conf.num_queues; i++) { s->cmd_vqs[i] = virtio_add_queue(vdev, s->conf.virtqueue_size, cmd); } } static void virtio_scsi_device_realize(DeviceState *dev, Error **errp) { VirtIODevice *vdev = VIRTIO_DEVICE(dev); VirtIOSCSI *s = VIRTIO_SCSI(dev); Error *err = NULL; QTAILQ_INIT(&s->tmf_bh_list); qemu_mutex_init(&s->tmf_bh_lock); virtio_scsi_common_realize(dev, virtio_scsi_handle_ctrl, virtio_scsi_handle_event, virtio_scsi_handle_cmd, &err); if (err != NULL) { error_propagate(errp, err); return; } scsi_bus_init_named(&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), OBJECT(dev)); virtio_scsi_dataplane_setup(s, errp); } void virtio_scsi_common_unrealize(DeviceState *dev) { VirtIODevice *vdev = VIRTIO_DEVICE(dev); VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(dev); int i; virtio_delete_queue(vs->ctrl_vq); virtio_delete_queue(vs->event_vq); for (i = 0; i < vs->conf.num_queues; i++) { virtio_delete_queue(vs->cmd_vqs[i]); } g_free(vs->cmd_vqs); virtio_cleanup(vdev); } static void virtio_scsi_device_unrealize(DeviceState *dev) { VirtIOSCSI *s = VIRTIO_SCSI(dev); virtio_scsi_reset_tmf_bh(s); qbus_set_hotplug_handler(BUS(&s->bus), NULL); virtio_scsi_common_unrealize(dev); qemu_mutex_destroy(&s->tmf_bh_lock); } static Property virtio_scsi_properties[] = { DEFINE_PROP_UINT32("num_queues", VirtIOSCSI, parent_obj.conf.num_queues, VIRTIO_SCSI_AUTO_NUM_QUEUES), DEFINE_PROP_UINT32("virtqueue_size", VirtIOSCSI, parent_obj.conf.virtqueue_size, 256), DEFINE_PROP_BOOL("seg_max_adjust", VirtIOSCSI, parent_obj.conf.seg_max_adjust, true), 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_LINK("iothread", VirtIOSCSI, parent_obj.conf.iothread, TYPE_IOTHREAD, IOThread *), DEFINE_PROP_END_OF_LIST(), }; static const VMStateDescription vmstate_virtio_scsi = { .name = "virtio-scsi", .minimum_version_id = 1, .version_id = 1, .fields = (const VMStateField[]) { VMSTATE_VIRTIO_DEVICE, VMSTATE_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); device_class_set_props(dc, virtio_scsi_properties); dc->vmsd = &vmstate_virtio_scsi; 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; vdc->start_ioeventfd = virtio_scsi_dataplane_start; vdc->stop_ioeventfd = virtio_scsi_dataplane_stop; hc->pre_plug = virtio_scsi_pre_hotplug; 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), .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)