diff options
| -rw-r--r-- | drivers/vhost/tcm_vhost.c | 210 | ||||
| -rw-r--r-- | drivers/vhost/tcm_vhost.h | 10 |
2 files changed, 218 insertions, 2 deletions
diff --git a/drivers/vhost/tcm_vhost.c b/drivers/vhost/tcm_vhost.c index 822cd1fbff5..5340fd759c6 100644 --- a/drivers/vhost/tcm_vhost.c +++ b/drivers/vhost/tcm_vhost.c @@ -71,6 +71,7 @@ enum { #define VHOST_SCSI_MAX_TARGET 256 #define VHOST_SCSI_MAX_VQ 128 +#define VHOST_SCSI_MAX_EVENT 128 struct vhost_scsi { /* Protected by vhost_scsi->dev.mutex */ @@ -82,6 +83,12 @@ struct vhost_scsi { struct vhost_work vs_completion_work; /* cmd completion work item */ struct llist_head vs_completion_list; /* cmd completion queue */ + + struct vhost_work vs_event_work; /* evt injection work item */ + struct llist_head vs_event_list; /* evt injection queue */ + + bool vs_events_missed; /* any missed events, protected by vq->mutex */ + int vs_events_nr; /* num of pending events, protected by vq->mutex */ }; /* Local pointer to allocated TCM configfs fabric module */ @@ -349,6 +356,37 @@ static int tcm_vhost_queue_tm_rsp(struct se_cmd *se_cmd) return 0; } +static void tcm_vhost_free_evt(struct vhost_scsi *vs, struct tcm_vhost_evt *evt) +{ + vs->vs_events_nr--; + kfree(evt); +} + +static struct tcm_vhost_evt *tcm_vhost_allocate_evt(struct vhost_scsi *vs, + u32 event, u32 reason) +{ + struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT]; + struct tcm_vhost_evt *evt; + + if (vs->vs_events_nr > VHOST_SCSI_MAX_EVENT) { + vs->vs_events_missed = true; + return NULL; + } + + evt = kzalloc(sizeof(*evt), GFP_KERNEL); + if (!evt) { + vq_err(vq, "Failed to allocate tcm_vhost_evt\n"); + vs->vs_events_missed = true; + return NULL; + } + + evt->event.event = event; + evt->event.reason = reason; + vs->vs_events_nr++; + + return evt; +} + static void vhost_scsi_free_cmd(struct tcm_vhost_cmd *tv_cmd) { struct se_cmd *se_cmd = &tv_cmd->tvc_se_cmd; @@ -367,6 +405,75 @@ static void vhost_scsi_free_cmd(struct tcm_vhost_cmd *tv_cmd) kfree(tv_cmd); } +static void tcm_vhost_do_evt_work(struct vhost_scsi *vs, + struct tcm_vhost_evt *evt) +{ + struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT]; + struct virtio_scsi_event *event = &evt->event; + struct virtio_scsi_event __user *eventp; + unsigned out, in; + int head, ret; + + if (!vq->private_data) { + vs->vs_events_missed = true; + return; + } + +again: + vhost_disable_notify(&vs->dev, vq); + head = vhost_get_vq_desc(&vs->dev, vq, vq->iov, + ARRAY_SIZE(vq->iov), &out, &in, + NULL, NULL); + if (head < 0) { + vs->vs_events_missed = true; + return; + } + if (head == vq->num) { + if (vhost_enable_notify(&vs->dev, vq)) + goto again; + vs->vs_events_missed = true; + return; + } + + if ((vq->iov[out].iov_len != sizeof(struct virtio_scsi_event))) { + vq_err(vq, "Expecting virtio_scsi_event, got %zu bytes\n", + vq->iov[out].iov_len); + vs->vs_events_missed = true; + return; + } + + if (vs->vs_events_missed) { + event->event |= VIRTIO_SCSI_T_EVENTS_MISSED; + vs->vs_events_missed = false; + } + + eventp = vq->iov[out].iov_base; + ret = __copy_to_user(eventp, event, sizeof(*event)); + if (!ret) + vhost_add_used_and_signal(&vs->dev, vq, head, 0); + else + vq_err(vq, "Faulted on tcm_vhost_send_event\n"); +} + +static void tcm_vhost_evt_work(struct vhost_work *work) +{ + struct vhost_scsi *vs = container_of(work, struct vhost_scsi, + vs_event_work); + struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT]; + struct tcm_vhost_evt *evt; + struct llist_node *llnode; + + mutex_lock(&vq->mutex); + llnode = llist_del_all(&vs->vs_event_list); + while (llnode) { + evt = llist_entry(llnode, struct tcm_vhost_evt, list); + llnode = llist_next(llnode); + tcm_vhost_do_evt_work(vs, evt); + tcm_vhost_free_evt(vs, evt); + } + mutex_unlock(&vq->mutex); +} + /* Fill in status and signal that we are done processing this command * * This is scheduled in the vhost work queue so we are called with the owner @@ -777,9 +884,46 @@ static void vhost_scsi_ctl_handle_kick(struct vhost_work *work) pr_debug("%s: The handling func for control queue.\n", __func__); } +static void tcm_vhost_send_evt(struct vhost_scsi *vs, struct tcm_vhost_tpg *tpg, + struct se_lun *lun, u32 event, u32 reason) +{ + struct tcm_vhost_evt *evt; + + evt = tcm_vhost_allocate_evt(vs, event, reason); + if (!evt) + return; + + if (tpg && lun) { + /* TODO: share lun setup code with virtio-scsi.ko */ + /* + * Note: evt->event is zeroed when we allocate it and + * lun[4-7] need to be zero according to virtio-scsi spec. + */ + evt->event.lun[0] = 0x01; + evt->event.lun[1] = tpg->tport_tpgt & 0xFF; + if (lun->unpacked_lun >= 256) + evt->event.lun[2] = lun->unpacked_lun >> 8 | 0x40 ; + evt->event.lun[3] = lun->unpacked_lun & 0xFF; + } + + llist_add(&evt->list, &vs->vs_event_list); + vhost_work_queue(&vs->dev, &vs->vs_event_work); +} + static void vhost_scsi_evt_handle_kick(struct vhost_work *work) { - pr_debug("%s: The handling func for event queue.\n", __func__); + struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue, + poll.work); + struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev); + + mutex_lock(&vq->mutex); + if (!vq->private_data) + goto out; + + if (vs->vs_events_missed) + tcm_vhost_send_evt(vs, NULL, NULL, VIRTIO_SCSI_T_NO_EVENT, 0); +out: + mutex_unlock(&vq->mutex); } static void vhost_scsi_handle_kick(struct vhost_work *work) @@ -803,6 +947,7 @@ static void vhost_scsi_flush(struct vhost_scsi *vs) for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) vhost_scsi_flush_vq(vs, i); vhost_work_flush(&vs->dev, &vs->vs_completion_work); + vhost_work_flush(&vs->dev, &vs->vs_event_work); } /* @@ -864,6 +1009,7 @@ static int vhost_scsi_set_endpoint( goto out; } tv_tpg->tv_tpg_vhost_count++; + tv_tpg->vhost_scsi = vs; vs_tpg[tv_tpg->tport_tpgt] = tv_tpg; smp_mb__after_atomic_inc(); match = true; @@ -949,6 +1095,7 @@ static int vhost_scsi_clear_endpoint( goto err_tpg; } tv_tpg->tv_tpg_vhost_count--; + tv_tpg->vhost_scsi = NULL; vs->vs_tpg[target] = NULL; match = true; mutex_unlock(&tv_tpg->tv_tpg_mutex); @@ -969,6 +1116,7 @@ static int vhost_scsi_clear_endpoint( vhost_scsi_flush(vs); kfree(vs->vs_tpg); vs->vs_tpg = NULL; + WARN_ON(vs->vs_events_nr); mutex_unlock(&vs->dev.mutex); mutex_unlock(&tcm_vhost_mutex); return 0; @@ -1009,6 +1157,10 @@ static int vhost_scsi_open(struct inode *inode, struct file *f) return -ENOMEM; vhost_work_init(&s->vs_completion_work, vhost_scsi_complete_cmd_work); + vhost_work_init(&s->vs_event_work, tcm_vhost_evt_work); + + s->vs_events_nr = 0; + s->vs_events_missed = false; s->vqs[VHOST_SCSI_VQ_CTL].handle_kick = vhost_scsi_ctl_handle_kick; s->vqs[VHOST_SCSI_VQ_EVT].handle_kick = vhost_scsi_evt_handle_kick; @@ -1035,6 +1187,8 @@ static int vhost_scsi_release(struct inode *inode, struct file *f) vhost_scsi_clear_endpoint(s, &t); vhost_dev_stop(&s->dev); vhost_dev_cleanup(&s->dev, false); + /* Jobs can re-queue themselves in evt kick handler. Do extra flush. */ + vhost_scsi_flush(s); kfree(s); return 0; } @@ -1139,28 +1293,80 @@ static char *tcm_vhost_dump_proto_id(struct tcm_vhost_tport *tport) return "Unknown"; } +static void tcm_vhost_do_plug(struct tcm_vhost_tpg *tpg, + struct se_lun *lun, bool plug) +{ + + struct vhost_scsi *vs = tpg->vhost_scsi; + struct vhost_virtqueue *vq; + u32 reason; + + if (!vs) + return; + + mutex_lock(&vs->dev.mutex); + if (!vhost_has_feature(&vs->dev, VIRTIO_SCSI_F_HOTPLUG)) { + mutex_unlock(&vs->dev.mutex); + return; + } + + if (plug) + reason = VIRTIO_SCSI_EVT_RESET_RESCAN; + else + reason = VIRTIO_SCSI_EVT_RESET_REMOVED; + + vq = &vs->vqs[VHOST_SCSI_VQ_EVT]; + mutex_lock(&vq->mutex); + tcm_vhost_send_evt(vs, tpg, lun, + VIRTIO_SCSI_T_TRANSPORT_RESET, reason); + mutex_unlock(&vq->mutex); + mutex_unlock(&vs->dev.mutex); +} + +static void tcm_vhost_hotplug(struct tcm_vhost_tpg *tpg, struct se_lun *lun) +{ + tcm_vhost_do_plug(tpg, lun, true); +} + +static void tcm_vhost_hotunplug(struct tcm_vhost_tpg *tpg, struct se_lun *lun) +{ + tcm_vhost_do_plug(tpg, lun, false); +} + static int tcm_vhost_port_link(struct se_portal_group *se_tpg, struct se_lun *lun) { struct tcm_vhost_tpg *tv_tpg = container_of(se_tpg, struct tcm_vhost_tpg, se_tpg); + mutex_lock(&tcm_vhost_mutex); + mutex_lock(&tv_tpg->tv_tpg_mutex); tv_tpg->tv_tpg_port_count++; mutex_unlock(&tv_tpg->tv_tpg_mutex); + tcm_vhost_hotplug(tv_tpg, lun); + + mutex_unlock(&tcm_vhost_mutex); + return 0; } static void tcm_vhost_port_unlink(struct se_portal_group *se_tpg, - struct se_lun *se_lun) + struct se_lun *lun) { struct tcm_vhost_tpg *tv_tpg = container_of(se_tpg, struct tcm_vhost_tpg, se_tpg); + mutex_lock(&tcm_vhost_mutex); + mutex_lock(&tv_tpg->tv_tpg_mutex); tv_tpg->tv_tpg_port_count--; mutex_unlock(&tv_tpg->tv_tpg_mutex); + + tcm_vhost_hotunplug(tv_tpg, lun); + + mutex_unlock(&tcm_vhost_mutex); } static struct se_node_acl *tcm_vhost_make_nodeacl( diff --git a/drivers/vhost/tcm_vhost.h b/drivers/vhost/tcm_vhost.h index 1d2ae7a60e1..a545a5b766a 100644 --- a/drivers/vhost/tcm_vhost.h +++ b/drivers/vhost/tcm_vhost.h @@ -53,6 +53,7 @@ struct tcm_vhost_nacl { struct se_node_acl se_node_acl; }; +struct vhost_scsi; struct tcm_vhost_tpg { /* Vhost port target portal group tag for TCM */ u16 tport_tpgt; @@ -70,6 +71,8 @@ struct tcm_vhost_tpg { struct tcm_vhost_tport *tport; /* Returned by tcm_vhost_make_tpg() */ struct se_portal_group se_tpg; + /* Pointer back to vhost_scsi, protected by tv_tpg_mutex */ + struct vhost_scsi *vhost_scsi; }; struct tcm_vhost_tport { @@ -83,6 +86,13 @@ struct tcm_vhost_tport { struct se_wwn tport_wwn; }; +struct tcm_vhost_evt { + /* event to be sent to guest */ + struct virtio_scsi_event event; + /* event list, serviced from vhost worker thread */ + struct llist_node list; +}; + /* * As per request from MST, keep TCM_VHOST related ioctl defines out of * linux/vhost.h (user-space) for now.. |