1 files changed, 64 insertions, 110 deletions

diff --git a/drivers/vhost/scsi.c b/drivers/vhost/scsi.c
index b244e7c0f514..bb10fa4bb4f6 100644
--- a/drivers/vhost/scsi.c
+++ b/drivers/vhost/scsi.c
@@ -125,7 +125,6 @@ struct vhost_scsi_tpg {
 	struct se_portal_group se_tpg;
 	/* Pointer back to vhost_scsi, protected by tv_tpg_mutex */
 	struct vhost_scsi *vhost_scsi;
-	struct list_head tmf_queue;
 };
 
 struct vhost_scsi_tport {
@@ -206,10 +205,8 @@ struct vhost_scsi {
 
 struct vhost_scsi_tmf {
 	struct vhost_work vwork;
-	struct vhost_scsi_tpg *tpg;
 	struct vhost_scsi *vhost;
 	struct vhost_scsi_virtqueue *svq;
-	struct list_head queue_entry;
 
 	struct se_cmd se_cmd;
 	u8 scsi_resp;
@@ -232,7 +229,10 @@ struct vhost_scsi_ctx {
 	struct iov_iter out_iter;
 };
 
-/* Global spinlock to protect vhost_scsi TPG list for vhost IOCTL access */
+/*
+ * Global mutex to protect vhost_scsi TPG list for vhost IOCTLs and LIO
+ * configfs management operations.
+ */
 static DEFINE_MUTEX(vhost_scsi_mutex);
 static LIST_HEAD(vhost_scsi_list);
 
@@ -294,11 +294,6 @@ static int vhost_scsi_check_true(struct se_portal_group *se_tpg)
 	return 1;
 }
 
-static int vhost_scsi_check_false(struct se_portal_group *se_tpg)
-{
-	return 0;
-}
-
 static char *vhost_scsi_get_fabric_wwn(struct se_portal_group *se_tpg)
 {
 	struct vhost_scsi_tpg *tpg = container_of(se_tpg,
@@ -323,11 +318,6 @@ static int vhost_scsi_check_prot_fabric_only(struct se_portal_group *se_tpg)
 	return tpg->tv_fabric_prot_type;
 }
 
-static u32 vhost_scsi_tpg_get_inst_index(struct se_portal_group *se_tpg)
-{
-	return 1;
-}
-
 static void vhost_scsi_release_cmd_res(struct se_cmd *se_cmd)
 {
 	struct vhost_scsi_cmd *tv_cmd = container_of(se_cmd,
@@ -352,12 +342,9 @@ static void vhost_scsi_release_cmd_res(struct se_cmd *se_cmd)
 
 static void vhost_scsi_release_tmf_res(struct vhost_scsi_tmf *tmf)
 {
-	struct vhost_scsi_tpg *tpg = tmf->tpg;
 	struct vhost_scsi_inflight *inflight = tmf->inflight;
 
-	mutex_lock(&tpg->tv_tpg_mutex);
-	list_add_tail(&tpg->tmf_queue, &tmf->queue_entry);
-	mutex_unlock(&tpg->tv_tpg_mutex);
+	kfree(tmf);
 	vhost_scsi_put_inflight(inflight);
 }
 
@@ -378,11 +365,6 @@ static void vhost_scsi_release_cmd(struct se_cmd *se_cmd)
 	}
 }
 
-static u32 vhost_scsi_sess_get_index(struct se_session *se_sess)
-{
-	return 0;
-}
-
 static int vhost_scsi_write_pending(struct se_cmd *se_cmd)
 {
 	/* Go ahead and process the write immediately */
@@ -390,16 +372,6 @@ static int vhost_scsi_write_pending(struct se_cmd *se_cmd)
 	return 0;
 }
 
-static void vhost_scsi_set_default_node_attrs(struct se_node_acl *nacl)
-{
-	return;
-}
-
-static int vhost_scsi_get_cmd_state(struct se_cmd *se_cmd)
-{
-	return 0;
-}
-
 static int vhost_scsi_queue_data_in(struct se_cmd *se_cmd)
 {
 	transport_generic_free_cmd(se_cmd, 0);
@@ -671,7 +643,7 @@ vhost_scsi_calc_sgls(struct iov_iter *iter, size_t bytes, int max_sgls)
 {
 	int sgl_count = 0;
 
-	if (!iter || !iter->iov) {
+	if (!iter || !iter_iov(iter)) {
 		pr_err("%s: iter->iov is NULL, but expected bytes: %zu"
 		       " present\n", __func__, bytes);
 		return -EINVAL;
@@ -1194,19 +1166,11 @@ vhost_scsi_handle_tmf(struct vhost_scsi *vs, struct vhost_scsi_tpg *tpg,
 		goto send_reject;
 	}
 
-	mutex_lock(&tpg->tv_tpg_mutex);
-	if (list_empty(&tpg->tmf_queue)) {
-		pr_err("Missing reserve TMF. Could not handle LUN RESET.\n");
-		mutex_unlock(&tpg->tv_tpg_mutex);
+	tmf = kzalloc(sizeof(*tmf), GFP_KERNEL);
+	if (!tmf)
 		goto send_reject;
-	}
-
-	tmf = list_first_entry(&tpg->tmf_queue, struct vhost_scsi_tmf,
-			       queue_entry);
-	list_del_init(&tmf->queue_entry);
-	mutex_unlock(&tpg->tv_tpg_mutex);
 
-	tmf->tpg = tpg;
+	vhost_work_init(&tmf->vwork, vhost_scsi_tmf_resp_work);
 	tmf->vhost = vs;
 	tmf->svq = svq;
 	tmf->resp_iov = vq->iov[vc->out];
@@ -1540,7 +1504,7 @@ out:
  * vhost_scsi_tpg with an active struct vhost_scsi_nexus
  *
  *  The lock nesting rule is:
- *    vhost_scsi_mutex -> vs->dev.mutex -> tpg->tv_tpg_mutex -> vq->mutex
+ *    vs->dev.mutex -> vhost_scsi_mutex -> tpg->tv_tpg_mutex -> vq->mutex
  */
 static int
 vhost_scsi_set_endpoint(struct vhost_scsi *vs,
@@ -1554,7 +1518,6 @@ vhost_scsi_set_endpoint(struct vhost_scsi *vs,
 	int index, ret, i, len;
 	bool match = false;
 
-	mutex_lock(&vhost_scsi_mutex);
 	mutex_lock(&vs->dev.mutex);
 
 	/* Verify that ring has been setup correctly. */
@@ -1575,6 +1538,7 @@ vhost_scsi_set_endpoint(struct vhost_scsi *vs,
 	if (vs->vs_tpg)
 		memcpy(vs_tpg, vs->vs_tpg, len);
 
+	mutex_lock(&vhost_scsi_mutex);
 	list_for_each_entry(tpg, &vhost_scsi_list, tv_tpg_list) {
 		mutex_lock(&tpg->tv_tpg_mutex);
 		if (!tpg->tpg_nexus) {
@@ -1590,6 +1554,7 @@ vhost_scsi_set_endpoint(struct vhost_scsi *vs,
 		if (!strcmp(tv_tport->tport_name, t->vhost_wwpn)) {
 			if (vs->vs_tpg && vs->vs_tpg[tpg->tport_tpgt]) {
 				mutex_unlock(&tpg->tv_tpg_mutex);
+				mutex_unlock(&vhost_scsi_mutex);
 				ret = -EEXIST;
 				goto undepend;
 			}
@@ -1604,6 +1569,7 @@ vhost_scsi_set_endpoint(struct vhost_scsi *vs,
 			if (ret) {
 				pr_warn("target_depend_item() failed: %d\n", ret);
 				mutex_unlock(&tpg->tv_tpg_mutex);
+				mutex_unlock(&vhost_scsi_mutex);
 				goto undepend;
 			}
 			tpg->tv_tpg_vhost_count++;
@@ -1613,6 +1579,7 @@ vhost_scsi_set_endpoint(struct vhost_scsi *vs,
 		}
 		mutex_unlock(&tpg->tv_tpg_mutex);
 	}
+	mutex_unlock(&vhost_scsi_mutex);
 
 	if (match) {
 		memcpy(vs->vs_vhost_wwpn, t->vhost_wwpn,
@@ -1658,14 +1625,16 @@ undepend:
 	for (i = 0; i < VHOST_SCSI_MAX_TARGET; i++) {
 		tpg = vs_tpg[i];
 		if (tpg) {
+			mutex_lock(&tpg->tv_tpg_mutex);
+			tpg->vhost_scsi = NULL;
 			tpg->tv_tpg_vhost_count--;
+			mutex_unlock(&tpg->tv_tpg_mutex);
 			target_undepend_item(&tpg->se_tpg.tpg_group.cg_item);
 		}
 	}
 	kfree(vs_tpg);
 out:
 	mutex_unlock(&vs->dev.mutex);
-	mutex_unlock(&vhost_scsi_mutex);
 	return ret;
 }
 
@@ -1681,7 +1650,6 @@ vhost_scsi_clear_endpoint(struct vhost_scsi *vs,
 	int index, ret, i;
 	u8 target;
 
-	mutex_lock(&vhost_scsi_mutex);
 	mutex_lock(&vs->dev.mutex);
 	/* Verify that ring has been setup correctly. */
 	for (index = 0; index < vs->dev.nvqs; ++index) {
@@ -1702,11 +1670,10 @@ vhost_scsi_clear_endpoint(struct vhost_scsi *vs,
 		if (!tpg)
 			continue;
 
-		mutex_lock(&tpg->tv_tpg_mutex);
 		tv_tport = tpg->tport;
 		if (!tv_tport) {
 			ret = -ENODEV;
-			goto err_tpg;
+			goto err_dev;
 		}
 
 		if (strcmp(tv_tport->tport_name, t->vhost_wwpn)) {
@@ -1715,35 +1682,51 @@ vhost_scsi_clear_endpoint(struct vhost_scsi *vs,
 				tv_tport->tport_name, tpg->tport_tpgt,
 				t->vhost_wwpn, t->vhost_tpgt);
 			ret = -EINVAL;
-			goto err_tpg;
+			goto err_dev;
 		}
+		match = true;
+	}
+	if (!match)
+		goto free_vs_tpg;
+
+	/* Prevent new cmds from starting and accessing the tpgs/sessions */
+	for (i = 0; i < vs->dev.nvqs; i++) {
+		vq = &vs->vqs[i].vq;
+		mutex_lock(&vq->mutex);
+		vhost_vq_set_backend(vq, NULL);
+		mutex_unlock(&vq->mutex);
+	}
+	/* Make sure cmds are not running before tearing them down. */
+	vhost_scsi_flush(vs);
+
+	for (i = 0; i < vs->dev.nvqs; i++) {
+		vq = &vs->vqs[i].vq;
+		vhost_scsi_destroy_vq_cmds(vq);
+	}
+
+	/*
+	 * We can now release our hold on the tpg and sessions and userspace
+	 * can free them after this point.
+	 */
+	for (i = 0; i < VHOST_SCSI_MAX_TARGET; i++) {
+		target = i;
+		tpg = vs->vs_tpg[target];
+		if (!tpg)
+			continue;
+
+		mutex_lock(&tpg->tv_tpg_mutex);
+
 		tpg->tv_tpg_vhost_count--;
 		tpg->vhost_scsi = NULL;
 		vs->vs_tpg[target] = NULL;
-		match = true;
+
 		mutex_unlock(&tpg->tv_tpg_mutex);
-		/*
-		 * Release se_tpg->tpg_group.cg_item configfs dependency now
-		 * to allow vhost-scsi WWPN se_tpg->tpg_group shutdown to occur.
-		 */
+
 		se_tpg = &tpg->se_tpg;
 		target_undepend_item(&se_tpg->tpg_group.cg_item);
 	}
-	if (match) {
-		for (i = 0; i < vs->dev.nvqs; i++) {
-			vq = &vs->vqs[i].vq;
-			mutex_lock(&vq->mutex);
-			vhost_vq_set_backend(vq, NULL);
-			mutex_unlock(&vq->mutex);
-		}
-		/* Make sure cmds are not running before tearing them down. */
-		vhost_scsi_flush(vs);
 
-		for (i = 0; i < vs->dev.nvqs; i++) {
-			vq = &vs->vqs[i].vq;
-			vhost_scsi_destroy_vq_cmds(vq);
-		}
-	}
+free_vs_tpg:
 	/*
 	 * Act as synchronize_rcu to make sure access to
 	 * old vs->vs_tpg is finished.
@@ -1753,14 +1736,10 @@ vhost_scsi_clear_endpoint(struct vhost_scsi *vs,
 	vs->vs_tpg = NULL;
 	WARN_ON(vs->vs_events_nr);
 	mutex_unlock(&vs->dev.mutex);
-	mutex_unlock(&vhost_scsi_mutex);
 	return 0;
 
-err_tpg:
-	mutex_unlock(&tpg->tv_tpg_mutex);
 err_dev:
 	mutex_unlock(&vs->dev.mutex);
-	mutex_unlock(&vhost_scsi_mutex);
 	return ret;
 }
 
@@ -2001,8 +1980,6 @@ vhost_scsi_do_plug(struct vhost_scsi_tpg *tpg,
 	if (!vs)
 		return;
 
-	mutex_lock(&vs->dev.mutex);
-
 	if (plug)
 		reason = VIRTIO_SCSI_EVT_RESET_RESCAN;
 	else
@@ -2010,11 +1987,18 @@ vhost_scsi_do_plug(struct vhost_scsi_tpg *tpg,
 
 	vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
 	mutex_lock(&vq->mutex);
+	/*
+	 * We can't queue events if the backend has been cleared, because
+	 * we could end up queueing an event after the flush.
+	 */
+	if (!vhost_vq_get_backend(vq))
+		goto unlock;
+
 	if (vhost_has_feature(vq, VIRTIO_SCSI_F_HOTPLUG))
 		vhost_scsi_send_evt(vs, tpg, lun,
 				   VIRTIO_SCSI_T_TRANSPORT_RESET, reason);
+unlock:
 	mutex_unlock(&vq->mutex);
-	mutex_unlock(&vs->dev.mutex);
 }
 
 static void vhost_scsi_hotplug(struct vhost_scsi_tpg *tpg, struct se_lun *lun)
@@ -2032,24 +2016,11 @@ static int vhost_scsi_port_link(struct se_portal_group *se_tpg,
 {
 	struct vhost_scsi_tpg *tpg = container_of(se_tpg,
 				struct vhost_scsi_tpg, se_tpg);
-	struct vhost_scsi_tmf *tmf;
-
-	tmf = kzalloc(sizeof(*tmf), GFP_KERNEL);
-	if (!tmf)
-		return -ENOMEM;
-	INIT_LIST_HEAD(&tmf->queue_entry);
-	vhost_work_init(&tmf->vwork, vhost_scsi_tmf_resp_work);
-
-	mutex_lock(&vhost_scsi_mutex);
 
 	mutex_lock(&tpg->tv_tpg_mutex);
 	tpg->tv_tpg_port_count++;
-	list_add_tail(&tmf->queue_entry, &tpg->tmf_queue);
-	mutex_unlock(&tpg->tv_tpg_mutex);
-
 	vhost_scsi_hotplug(tpg, lun);
-
-	mutex_unlock(&vhost_scsi_mutex);
+	mutex_unlock(&tpg->tv_tpg_mutex);
 
 	return 0;
 }
@@ -2059,21 +2030,11 @@ static void vhost_scsi_port_unlink(struct se_portal_group *se_tpg,
 {
 	struct vhost_scsi_tpg *tpg = container_of(se_tpg,
 				struct vhost_scsi_tpg, se_tpg);
-	struct vhost_scsi_tmf *tmf;
-
-	mutex_lock(&vhost_scsi_mutex);
 
 	mutex_lock(&tpg->tv_tpg_mutex);
 	tpg->tv_tpg_port_count--;
-	tmf = list_first_entry(&tpg->tmf_queue, struct vhost_scsi_tmf,
-			       queue_entry);
-	list_del(&tmf->queue_entry);
-	kfree(tmf);
-	mutex_unlock(&tpg->tv_tpg_mutex);
-
 	vhost_scsi_hotunplug(tpg, lun);
-
-	mutex_unlock(&vhost_scsi_mutex);
+	mutex_unlock(&tpg->tv_tpg_mutex);
 }
 
 static ssize_t vhost_scsi_tpg_attrib_fabric_prot_type_store(
@@ -2329,7 +2290,6 @@ vhost_scsi_make_tpg(struct se_wwn *wwn, const char *name)
 	}
 	mutex_init(&tpg->tv_tpg_mutex);
 	INIT_LIST_HEAD(&tpg->tv_tpg_list);
-	INIT_LIST_HEAD(&tpg->tmf_queue);
 	tpg->tport = tport;
 	tpg->tport_tpgt = tpgt;
 
@@ -2460,17 +2420,11 @@ static const struct target_core_fabric_ops vhost_scsi_ops = {
 	.tpg_get_tag			= vhost_scsi_get_tpgt,
 	.tpg_check_demo_mode		= vhost_scsi_check_true,
 	.tpg_check_demo_mode_cache	= vhost_scsi_check_true,
-	.tpg_check_demo_mode_write_protect = vhost_scsi_check_false,
-	.tpg_check_prod_mode_write_protect = vhost_scsi_check_false,
 	.tpg_check_prot_fabric_only	= vhost_scsi_check_prot_fabric_only,
-	.tpg_get_inst_index		= vhost_scsi_tpg_get_inst_index,
 	.release_cmd			= vhost_scsi_release_cmd,
 	.check_stop_free		= vhost_scsi_check_stop_free,
-	.sess_get_index			= vhost_scsi_sess_get_index,
 	.sess_get_initiator_sid		= NULL,
 	.write_pending			= vhost_scsi_write_pending,
-	.set_default_node_attributes	= vhost_scsi_set_default_node_attrs,
-	.get_cmd_state			= vhost_scsi_get_cmd_state,
 	.queue_data_in			= vhost_scsi_queue_data_in,
 	.queue_status			= vhost_scsi_queue_status,
 	.queue_tm_rsp			= vhost_scsi_queue_tm_rsp,