1 files changed, 286 insertions, 10 deletions

diff --git a/drivers/nvme/target/fc.c b/drivers/nvme/target/fc.c
index 6a5af99f19ba..02d9751bb7ee 100644
--- a/drivers/nvme/target/fc.c
+++ b/drivers/nvme/target/fc.c
@@ -25,7 +25,7 @@
 struct nvmet_fc_tgtport;
 struct nvmet_fc_tgt_assoc;
 
-struct nvmet_fc_ls_iod {
+struct nvmet_fc_ls_iod {		/* for an LS RQST RCV */
 	struct nvmefc_ls_rsp		*lsrsp;
 	struct nvmefc_tgt_fcp_req	*fcpreq;	/* only if RS */
 
@@ -45,6 +45,18 @@ struct nvmet_fc_ls_iod {
 	struct work_struct		work;
 } __aligned(sizeof(unsigned long long));
 
+struct nvmet_fc_ls_req_op {		/* for an LS RQST XMT */
+	struct nvmefc_ls_req		ls_req;
+
+	struct nvmet_fc_tgtport		*tgtport;
+	void				*hosthandle;
+
+	int				ls_error;
+	struct list_head		lsreq_list; /* tgtport->ls_req_list */
+	bool				req_queued;
+};
+
+
 /* desired maximum for a single sequence - if sg list allows it */
 #define NVMET_FC_MAX_SEQ_LENGTH		(256 * 1024)
 
@@ -91,6 +103,7 @@ struct nvmet_fc_tgtport {
 	struct nvmet_fc_ls_iod		*iod;
 	spinlock_t			lock;
 	struct list_head		ls_rcv_list;
+	struct list_head		ls_req_list;
 	struct list_head		ls_busylist;
 	struct list_head		assoc_list;
 	struct list_head		host_list;
@@ -146,8 +159,10 @@ struct nvmet_fc_hostport {
 struct nvmet_fc_tgt_assoc {
 	u64				association_id;
 	u32				a_id;
+	atomic_t			terminating;
 	struct nvmet_fc_tgtport		*tgtport;
 	struct nvmet_fc_hostport	*hostport;
+	struct nvmet_fc_ls_iod		*rcv_disconn;
 	struct list_head		a_list;
 	struct nvmet_fc_tgt_queue	*queues[NVMET_NR_QUEUES + 1];
 	struct kref			ref;
@@ -236,6 +251,8 @@ static int nvmet_fc_tgtport_get(struct nvmet_fc_tgtport *tgtport);
 static void nvmet_fc_handle_fcp_rqst(struct nvmet_fc_tgtport *tgtport,
 					struct nvmet_fc_fcp_iod *fod);
 static void nvmet_fc_delete_target_assoc(struct nvmet_fc_tgt_assoc *assoc);
+static void nvmet_fc_xmt_ls_rsp(struct nvmet_fc_tgtport *tgtport,
+				struct nvmet_fc_ls_iod *iod);
 
 
 /* *********************** FC-NVME DMA Handling **************************** */
@@ -327,6 +344,188 @@ fc_dma_unmap_sg(struct device *dev, struct scatterlist *sg, int nents,
 }
 
 
+/* ********************** FC-NVME LS XMT Handling ************************* */
+
+
+static void
+__nvmet_fc_finish_ls_req(struct nvmet_fc_ls_req_op *lsop)
+{
+	struct nvmet_fc_tgtport *tgtport = lsop->tgtport;
+	struct nvmefc_ls_req *lsreq = &lsop->ls_req;
+	unsigned long flags;
+
+	spin_lock_irqsave(&tgtport->lock, flags);
+
+	if (!lsop->req_queued) {
+		spin_unlock_irqrestore(&tgtport->lock, flags);
+		return;
+	}
+
+	list_del(&lsop->lsreq_list);
+
+	lsop->req_queued = false;
+
+	spin_unlock_irqrestore(&tgtport->lock, flags);
+
+	fc_dma_unmap_single(tgtport->dev, lsreq->rqstdma,
+				  (lsreq->rqstlen + lsreq->rsplen),
+				  DMA_BIDIRECTIONAL);
+
+	nvmet_fc_tgtport_put(tgtport);
+}
+
+static int
+__nvmet_fc_send_ls_req(struct nvmet_fc_tgtport *tgtport,
+		struct nvmet_fc_ls_req_op *lsop,
+		void (*done)(struct nvmefc_ls_req *req, int status))
+{
+	struct nvmefc_ls_req *lsreq = &lsop->ls_req;
+	unsigned long flags;
+	int ret = 0;
+
+	if (!tgtport->ops->ls_req)
+		return -EOPNOTSUPP;
+
+	if (!nvmet_fc_tgtport_get(tgtport))
+		return -ESHUTDOWN;
+
+	lsreq->done = done;
+	lsop->req_queued = false;
+	INIT_LIST_HEAD(&lsop->lsreq_list);
+
+	lsreq->rqstdma = fc_dma_map_single(tgtport->dev, lsreq->rqstaddr,
+				  lsreq->rqstlen + lsreq->rsplen,
+				  DMA_BIDIRECTIONAL);
+	if (fc_dma_mapping_error(tgtport->dev, lsreq->rqstdma)) {
+		ret = -EFAULT;
+		goto out_puttgtport;
+	}
+	lsreq->rspdma = lsreq->rqstdma + lsreq->rqstlen;
+
+	spin_lock_irqsave(&tgtport->lock, flags);
+
+	list_add_tail(&lsop->lsreq_list, &tgtport->ls_req_list);
+
+	lsop->req_queued = true;
+
+	spin_unlock_irqrestore(&tgtport->lock, flags);
+
+	ret = tgtport->ops->ls_req(&tgtport->fc_target_port, lsop->hosthandle,
+				   lsreq);
+	if (ret)
+		goto out_unlink;
+
+	return 0;
+
+out_unlink:
+	lsop->ls_error = ret;
+	spin_lock_irqsave(&tgtport->lock, flags);
+	lsop->req_queued = false;
+	list_del(&lsop->lsreq_list);
+	spin_unlock_irqrestore(&tgtport->lock, flags);
+	fc_dma_unmap_single(tgtport->dev, lsreq->rqstdma,
+				  (lsreq->rqstlen + lsreq->rsplen),
+				  DMA_BIDIRECTIONAL);
+out_puttgtport:
+	nvmet_fc_tgtport_put(tgtport);
+
+	return ret;
+}
+
+static int
+nvmet_fc_send_ls_req_async(struct nvmet_fc_tgtport *tgtport,
+		struct nvmet_fc_ls_req_op *lsop,
+		void (*done)(struct nvmefc_ls_req *req, int status))
+{
+	/* don't wait for completion */
+
+	return __nvmet_fc_send_ls_req(tgtport, lsop, done);
+}
+
+static void
+nvmet_fc_disconnect_assoc_done(struct nvmefc_ls_req *lsreq, int status)
+{
+	struct nvmet_fc_ls_req_op *lsop =
+		container_of(lsreq, struct nvmet_fc_ls_req_op, ls_req);
+
+	__nvmet_fc_finish_ls_req(lsop);
+
+	/* fc-nvme target doesn't care about success or failure of cmd */
+
+	kfree(lsop);
+}
+
+/*
+ * This routine sends a FC-NVME LS to disconnect (aka terminate)
+ * the FC-NVME Association.  Terminating the association also
+ * terminates the FC-NVME connections (per queue, both admin and io
+ * queues) that are part of the association. E.g. things are torn
+ * down, and the related FC-NVME Association ID and Connection IDs
+ * become invalid.
+ *
+ * The behavior of the fc-nvme target is such that it's
+ * understanding of the association and connections will implicitly
+ * be torn down. The action is implicit as it may be due to a loss of
+ * connectivity with the fc-nvme host, so the target may never get a
+ * response even if it tried.  As such, the action of this routine
+ * is to asynchronously send the LS, ignore any results of the LS, and
+ * continue on with terminating the association. If the fc-nvme host
+ * is present and receives the LS, it too can tear down.
+ */
+static void
+nvmet_fc_xmt_disconnect_assoc(struct nvmet_fc_tgt_assoc *assoc)
+{
+	struct nvmet_fc_tgtport *tgtport = assoc->tgtport;
+	struct fcnvme_ls_disconnect_assoc_rqst *discon_rqst;
+	struct fcnvme_ls_disconnect_assoc_acc *discon_acc;
+	struct nvmet_fc_ls_req_op *lsop;
+	struct nvmefc_ls_req *lsreq;
+	int ret;
+
+	/*
+	 * If ls_req is NULL or no hosthandle, it's an older lldd and no
+	 * message is normal. Otherwise, send unless the hostport has
+	 * already been invalidated by the lldd.
+	 */
+	if (!tgtport->ops->ls_req || !assoc->hostport ||
+	    assoc->hostport->invalid)
+		return;
+
+	lsop = kzalloc((sizeof(*lsop) +
+			sizeof(*discon_rqst) + sizeof(*discon_acc) +
+			tgtport->ops->lsrqst_priv_sz), GFP_KERNEL);
+	if (!lsop) {
+		dev_info(tgtport->dev,
+			"{%d:%d} send Disconnect Association failed: ENOMEM\n",
+			tgtport->fc_target_port.port_num, assoc->a_id);
+		return;
+	}
+
+	discon_rqst = (struct fcnvme_ls_disconnect_assoc_rqst *)&lsop[1];
+	discon_acc = (struct fcnvme_ls_disconnect_assoc_acc *)&discon_rqst[1];
+	lsreq = &lsop->ls_req;
+	if (tgtport->ops->lsrqst_priv_sz)
+		lsreq->private = (void *)&discon_acc[1];
+	else
+		lsreq->private = NULL;
+
+	lsop->tgtport = tgtport;
+	lsop->hosthandle = assoc->hostport->hosthandle;
+
+	nvmefc_fmt_lsreq_discon_assoc(lsreq, discon_rqst, discon_acc,
+				assoc->association_id);
+
+	ret = nvmet_fc_send_ls_req_async(tgtport, lsop,
+				nvmet_fc_disconnect_assoc_done);
+	if (ret) {
+		dev_info(tgtport->dev,
+			"{%d:%d} XMT Disconnect Association failed: %d\n",
+			tgtport->fc_target_port.port_num, assoc->a_id, ret);
+		kfree(lsop);
+	}
+}
+
+
 /* *********************** FC-NVME Port Management ************************ */
 
 
@@ -693,6 +892,10 @@ nvmet_fc_delete_target_queue(struct nvmet_fc_tgt_queue *queue)
 
 	disconnect = atomic_xchg(&queue->connected, 0);
 
+	/* if not connected, nothing to do */
+	if (!disconnect)
+		return;
+
 	spin_lock_irqsave(&queue->qlock, flags);
 	/* abort outstanding io's */
 	for (i = 0; i < queue->sqsize; fod++, i++) {
@@ -921,6 +1124,7 @@ nvmet_fc_alloc_target_assoc(struct nvmet_fc_tgtport *tgtport, void *hosthandle)
 	kref_init(&assoc->ref);
 	INIT_WORK(&assoc->del_work, nvmet_fc_delete_assoc);
 	atomic_set(&assoc->del_work_active, 0);
+	atomic_set(&assoc->terminating, 0);
 
 	while (needrandom) {
 		get_random_bytes(&ran, sizeof(ran) - BYTES_FOR_QID);
@@ -957,13 +1161,24 @@ nvmet_fc_target_assoc_free(struct kref *ref)
 	struct nvmet_fc_tgt_assoc *assoc =
 		container_of(ref, struct nvmet_fc_tgt_assoc, ref);
 	struct nvmet_fc_tgtport *tgtport = assoc->tgtport;
+	struct nvmet_fc_ls_iod	*oldls;
 	unsigned long flags;
 
+	/* Send Disconnect now that all i/o has completed */
+	nvmet_fc_xmt_disconnect_assoc(assoc);
+
 	nvmet_fc_free_hostport(assoc->hostport);
 	spin_lock_irqsave(&tgtport->lock, flags);
 	list_del(&assoc->a_list);
+	oldls = assoc->rcv_disconn;
 	spin_unlock_irqrestore(&tgtport->lock, flags);
+	/* if pending Rcv Disconnect Association LS, send rsp now */
+	if (oldls)
+		nvmet_fc_xmt_ls_rsp(tgtport, oldls);
 	ida_simple_remove(&tgtport->assoc_cnt, assoc->a_id);
+	dev_info(tgtport->dev,
+		"{%d:%d} Association freed\n",
+		tgtport->fc_target_port.port_num, assoc->a_id);
 	kfree(assoc);
 	nvmet_fc_tgtport_put(tgtport);
 }
@@ -986,7 +1201,13 @@ nvmet_fc_delete_target_assoc(struct nvmet_fc_tgt_assoc *assoc)
 	struct nvmet_fc_tgtport *tgtport = assoc->tgtport;
 	struct nvmet_fc_tgt_queue *queue;
 	unsigned long flags;
-	int i;
+	int i, terminating;
+
+	terminating = atomic_xchg(&assoc->terminating, 1);
+
+	/* if already terminating, do nothing */
+	if (terminating)
+		return;
 
 	spin_lock_irqsave(&tgtport->lock, flags);
 	for (i = NVMET_NR_QUEUES; i >= 0; i--) {
@@ -1002,6 +1223,10 @@ nvmet_fc_delete_target_assoc(struct nvmet_fc_tgt_assoc *assoc)
 	}
 	spin_unlock_irqrestore(&tgtport->lock, flags);
 
+	dev_info(tgtport->dev,
+		"{%d:%d} Association deleted\n",
+		tgtport->fc_target_port.port_num, assoc->a_id);
+
 	nvmet_fc_tgt_a_put(assoc);
 }
 
@@ -1171,6 +1396,7 @@ nvmet_fc_register_targetport(struct nvmet_fc_port_info *pinfo,
 	newrec->ops = template;
 	spin_lock_init(&newrec->lock);
 	INIT_LIST_HEAD(&newrec->ls_rcv_list);
+	INIT_LIST_HEAD(&newrec->ls_req_list);
 	INIT_LIST_HEAD(&newrec->ls_busylist);
 	INIT_LIST_HEAD(&newrec->assoc_list);
 	INIT_LIST_HEAD(&newrec->host_list);
@@ -1407,6 +1633,13 @@ nvmet_fc_unregister_targetport(struct nvmet_fc_target_port *target_port)
 	/* terminate any outstanding associations */
 	__nvmet_fc_free_assocs(tgtport);
 
+	/*
+	 * should terminate LS's as well. However, LS's will be generated
+	 * at the tail end of association termination, so they likely don't
+	 * exist yet. And even if they did, it's worthwhile to just let
+	 * them finish and targetport ref counting will clean things up.
+	 */
+
 	nvmet_fc_tgtport_put(tgtport);
 
 	return 0;
@@ -1414,7 +1647,7 @@ nvmet_fc_unregister_targetport(struct nvmet_fc_target_port *target_port)
 EXPORT_SYMBOL_GPL(nvmet_fc_unregister_targetport);
 
 
-/* *********************** FC-NVME LS Handling **************************** */
+/* ********************** FC-NVME LS RCV Handling ************************* */
 
 
 static void
@@ -1481,6 +1714,10 @@ nvmet_fc_ls_create_association(struct nvmet_fc_tgtport *tgtport,
 	atomic_set(&queue->connected, 1);
 	queue->sqhd = 0;	/* best place to init value */
 
+	dev_info(tgtport->dev,
+		"{%d:%d} Association created\n",
+		tgtport->fc_target_port.port_num, iod->assoc->a_id);
+
 	/* format a response */
 
 	iod->lsrsp->rsplen = sizeof(*acc);
@@ -1588,7 +1825,11 @@ nvmet_fc_ls_create_connection(struct nvmet_fc_tgtport *tgtport,
 				be16_to_cpu(rqst->connect_cmd.qid)));
 }
 
-static void
+/*
+ * Returns true if the LS response is to be transmit
+ * Returns false if the LS response is to be delayed
+ */
+static int
 nvmet_fc_ls_disconnect(struct nvmet_fc_tgtport *tgtport,
 			struct nvmet_fc_ls_iod *iod)
 {
@@ -1597,13 +1838,15 @@ nvmet_fc_ls_disconnect(struct nvmet_fc_tgtport *tgtport,
 	struct fcnvme_ls_disconnect_assoc_acc *acc =
 						&iod->rspbuf->rsp_dis_assoc;
 	struct nvmet_fc_tgt_assoc *assoc;
+	struct nvmet_fc_ls_iod *oldls = NULL;
+	unsigned long flags;
 	int ret = 0;
 
 	memset(acc, 0, sizeof(*acc));
 
 	ret = nvmefc_vldt_lsreq_discon_assoc(iod->rqstdatalen, rqst);
 	if (!ret) {
-		/* match an active association */
+		/* match an active association - takes an assoc ref if !NULL */
 		assoc = nvmet_fc_find_target_assoc(tgtport,
 				be64_to_cpu(rqst->associd.association_id));
 		iod->assoc = assoc;
@@ -1621,7 +1864,7 @@ nvmet_fc_ls_disconnect(struct nvmet_fc_tgtport *tgtport,
 					FCNVME_RJT_RC_INV_ASSOC :
 					FCNVME_RJT_RC_LOGIC,
 				FCNVME_RJT_EXP_NONE, 0);
-		return;
+		return true;
 	}
 
 	/* format a response */
@@ -1634,9 +1877,40 @@ nvmet_fc_ls_disconnect(struct nvmet_fc_tgtport *tgtport,
 			FCNVME_LS_DISCONNECT_ASSOC);
 
 	/* release get taken in nvmet_fc_find_target_assoc */
-	nvmet_fc_tgt_a_put(iod->assoc);
+	nvmet_fc_tgt_a_put(assoc);
+
+	/*
+	 * The rules for LS response says the response cannot
+	 * go back until ABTS's have been sent for all outstanding
+	 * I/O and a Disconnect Association LS has been sent.
+	 * So... save off the Disconnect LS to send the response
+	 * later. If there was a prior LS already saved, replace
+	 * it with the newer one and send a can't perform reject
+	 * on the older one.
+	 */
+	spin_lock_irqsave(&tgtport->lock, flags);
+	oldls = assoc->rcv_disconn;
+	assoc->rcv_disconn = iod;
+	spin_unlock_irqrestore(&tgtport->lock, flags);
 
-	nvmet_fc_delete_target_assoc(iod->assoc);
+	nvmet_fc_delete_target_assoc(assoc);
+
+	if (oldls) {
+		dev_info(tgtport->dev,
+			"{%d:%d} Multiple Disconnect Association LS's "
+			"received\n",
+			tgtport->fc_target_port.port_num, assoc->a_id);
+		/* overwrite good response with bogus failure */
+		oldls->lsrsp->rsplen = nvme_fc_format_rjt(oldls->rspbuf,
+						sizeof(*iod->rspbuf),
+						/* ok to use rqst, LS is same */
+						rqst->w0.ls_cmd,
+						FCNVME_RJT_RC_UNAB,
+						FCNVME_RJT_EXP_NONE, 0);
+		nvmet_fc_xmt_ls_rsp(tgtport, oldls);
+	}
+
+	return false;
 }
 
 
@@ -1681,6 +1955,7 @@ nvmet_fc_handle_ls_rqst(struct nvmet_fc_tgtport *tgtport,
 			struct nvmet_fc_ls_iod *iod)
 {
 	struct fcnvme_ls_rqst_w0 *w0 = &iod->rqstbuf->rq_cr_assoc.w0;
+	bool sendrsp = true;
 
 	iod->lsrsp->nvme_fc_private = iod;
 	iod->lsrsp->rspbuf = iod->rspbuf;
@@ -1707,7 +1982,7 @@ nvmet_fc_handle_ls_rqst(struct nvmet_fc_tgtport *tgtport,
 		break;
 	case FCNVME_LS_DISCONNECT_ASSOC:
 		/* Terminate a Queue/Connection or the Association */
-		nvmet_fc_ls_disconnect(tgtport, iod);
+		sendrsp = nvmet_fc_ls_disconnect(tgtport, iod);
 		break;
 	default:
 		iod->lsrsp->rsplen = nvme_fc_format_rjt(iod->rspbuf,
@@ -1715,7 +1990,8 @@ nvmet_fc_handle_ls_rqst(struct nvmet_fc_tgtport *tgtport,
 				FCNVME_RJT_RC_INVAL, FCNVME_RJT_EXP_NONE, 0);
 	}
 
-	nvmet_fc_xmt_ls_rsp(tgtport, iod);
+	if (sendrsp)
+		nvmet_fc_xmt_ls_rsp(tgtport, iod);
 }
 
 /*