summaryrefslogtreecommitdiffstats
path: root/hw/scsi/virtio-scsi.c
diff options
context:
space:
mode:
Diffstat (limited to 'hw/scsi/virtio-scsi.c')
-rw-r--r--hw/scsi/virtio-scsi.c1181
1 files changed, 1181 insertions, 0 deletions
diff --git a/hw/scsi/virtio-scsi.c b/hw/scsi/virtio-scsi.c
new file mode 100644
index 00000000..6f6e2e32
--- /dev/null
+++ b/hw/scsi/virtio-scsi.c
@@ -0,0 +1,1181 @@
+/*
+ * 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 "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/error-report.h"
+#include "qemu/iov.h"
+#include "qemu/module.h"
+#include "sysemu/block-backend.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;
+
+ union {
+ /* Used for two-stage request submission */
+ 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_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);
+ }
+}
+
+/* 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;
+ BusChild *kid;
+ int target;
+ 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, &notifier->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++;
+ device_cold_reset(&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_new(VirtIOSCSICancelNotifier, 1);
+ notifier->notifier.notify = virtio_scsi_cancel_notify;
+ notifier->tmf_req = req;
+ scsi_req_cancel_async(r, &notifier->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++;
+
+ 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();
+
+ s->resetting--;
+ 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_acquire(s);
+ virtio_scsi_handle_ctrl_vq(s, vq);
+ virtio_scsi_release(s);
+}
+
+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 (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 = &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);
+ 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);
+ blk_io_plug(d->conf.blk);
+ 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);
+ }
+ blk_io_unplug(sreq->dev->conf.blk);
+ 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);
+ blk_io_unplug(req->sreq->dev->conf.blk);
+ 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_acquire(s);
+ virtio_scsi_handle_cmd_vq(s, vq);
+ virtio_scsi_release(s);
+}
+
+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);
+ s->resetting++;
+ bus_cold_reset(BUS(&s->bus));
+ s->resetting--;
+
+ vs->sense_size = VIRTIO_SCSI_SENSE_DEFAULT_SIZE;
+ vs->cdb_size = VIRTIO_SCSI_CDB_DEFAULT_SIZE;
+ s->events_dropped = false;
+}
+
+static 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;
+ }
+
+ 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 (!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;
+ }
+ 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) {
+ virtio_scsi_push_event(s, NULL, VIRTIO_SCSI_T_NO_EVENT, 0);
+ }
+}
+
+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_acquire(s);
+ virtio_scsi_handle_event_vq(s, vq);
+ virtio_scsi_release(s);
+}
+
+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) {
+ virtio_scsi_acquire(s);
+ virtio_scsi_push_event(s, dev, VIRTIO_SCSI_T_PARAM_CHANGE,
+ sense.asc | (sense.ascq << 8));
+ virtio_scsi_release(s);
+ }
+}
+
+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);
+ AioContext *old_context;
+ int ret;
+
+ if (s->ctx && !s->dataplane_fenced) {
+ if (blk_op_is_blocked(sd->conf.blk, BLOCK_OP_TYPE_DATAPLANE, errp)) {
+ return;
+ }
+ old_context = blk_get_aio_context(sd->conf.blk);
+ aio_context_acquire(old_context);
+ ret = blk_set_aio_context(sd->conf.blk, s->ctx, errp);
+ aio_context_release(old_context);
+ if (ret < 0) {
+ return;
+ }
+ }
+
+ if (virtio_vdev_has_feature(vdev, VIRTIO_SCSI_F_HOTPLUG)) {
+ virtio_scsi_acquire(s);
+ virtio_scsi_push_event(s, sd,
+ VIRTIO_SCSI_T_TRANSPORT_RESET,
+ VIRTIO_SCSI_EVT_RESET_RESCAN);
+ scsi_bus_set_ua(&s->bus, SENSE_CODE(REPORTED_LUNS_CHANGED));
+ virtio_scsi_release(s);
+ }
+}
+
+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);
+ AioContext *ctx = s->ctx ?: qemu_get_aio_context();
+
+ if (virtio_vdev_has_feature(vdev, VIRTIO_SCSI_F_HOTPLUG)) {
+ virtio_scsi_acquire(s);
+ virtio_scsi_push_event(s, sd,
+ VIRTIO_SCSI_T_TRANSPORT_RESET,
+ VIRTIO_SCSI_EVT_RESET_REMOVED);
+ scsi_bus_set_ua(&s->bus, SENSE_CODE(REPORTED_LUNS_CHANGED));
+ virtio_scsi_release(s);
+ }
+
+ aio_disable_external(ctx);
+ qdev_simple_device_unplug_cb(hotplug_dev, dev, errp);
+ aio_enable_external(ctx);
+
+ if (s->ctx) {
+ virtio_scsi_acquire(s);
+ /* If other users keep the BlockBackend in the iothread, that's ok */
+ blk_set_aio_context(sd->conf.blk, qemu_get_aio_context(), NULL);
+ virtio_scsi_release(s);
+ }
+}
+
+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,
+};
+
+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;
+
+ 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);
+
+ qbus_set_hotplug_handler(BUS(&s->bus), NULL);
+ virtio_scsi_common_unrealize(dev);
+}
+
+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 = (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)