[PATCH v5 08/13] scsi: fnic: Handle NVMe LS frames in FDLS

[Karan Tilak Kumar <kartilak@cisco.com>]

Classify NVMe LS request OXIDs, route NVMe LS responses and ABTS frames
through the FCS receive path, and reset NVMe exchanges when FDLS tears
down target ports.

Extend FDLS link-down and frame-processing paths so NVMe LS traffic
follows the same discovery and cleanup state machine as FCP traffic.

Reviewed-by: Sesidhar Baddela <sebaddel@cisco.com>
Reviewed-by: Arulprabhu Ponnusamy <arulponn@cisco.com>
Reviewed-by: Gian Carlo Boffa <gcboffa@cisco.com>
Reviewed-by: Arun Easi <aeasi@cisco.com>
Reviewed-by: Hannes Reinecke <hare@kernel.org>
Reviewed-by: Lee Duncan <lduncan@suse.com>
Signed-off-by: Karan Tilak Kumar <kartilak@cisco.com>
Co-developed-by: Hannes Reinecke <hare@kernel.org>
---
Incorporate review comments from Lee Duncan:
	Replace the NVMe LS OXID switch with a direct frame-type check.
	Rename the NVMe frame helper to follow fnic function naming style.

Changes between v4 and v5:
Incorporate review comments from Sashiko:
	Check cleaned buffers before dereferencing them
	Drain OXID reclaim state on reset
---
 drivers/scsi/fnic/fdls_disc.c | 39 +++++++++++++++++++++++++++++++++++
 drivers/scsi/fnic/fnic_fcs.c  | 34 +++++++++++++++++++++++-------
 2 files changed, 66 insertions(+), 7 deletions(-)

diff --git a/drivers/scsi/fnic/fdls_disc.c b/drivers/scsi/fnic/fdls_disc.c
index e03256183ac6..f66c121cb712 100644
--- a/drivers/scsi/fnic/fdls_disc.c
+++ b/drivers/scsi/fnic/fdls_disc.c
@@ -387,10 +387,25 @@ static bool fdls_is_oxid_tgt_req(uint16_t oxid)
 	return true;
 }
 
+static inline bool fdls_is_oxid_nvme_req(uint16_t oxid)
+{
+	return FNIC_FRAME_TYPE(oxid) == FNIC_FRAME_TYPE_NVME_LS;
+}
+
 static void fdls_reset_oxid_pool(struct fnic_iport_s *iport)
 {
 	struct fnic_oxid_pool_s *oxid_pool = &iport->oxid_pool;
+	struct reclaim_entry_s *reclaim_entry, *next;
 
+	cancel_delayed_work(&oxid_pool->oxid_reclaim_work);
+	cancel_delayed_work(&oxid_pool->schedule_oxid_free_retry);
+	list_for_each_entry_safe(reclaim_entry, next,
+				 &oxid_pool->oxid_reclaim_list, links) {
+		list_del(&reclaim_entry->links);
+		kfree(reclaim_entry);
+	}
+	bitmap_clear(oxid_pool->pending_schedule_free, 0, FNIC_OXID_POOL_SZ);
+	bitmap_clear(oxid_pool->bitmap, 0, FNIC_OXID_POOL_SZ);
 	oxid_pool->next_idx = 0;
 }
 
@@ -1288,6 +1303,10 @@ bool fdls_delete_tport(struct fnic_iport_s *iport, struct fnic_tport_s *tport)
 		spin_unlock_irqrestore(&fnic->fnic_lock, fnic->lock_flags);
 		fnic_rport_exch_reset(iport->fnic, tport->fcid);
 		spin_lock_irqsave(&fnic->fnic_lock, fnic->lock_flags);
+	} else if (IS_FNIC_NVME_INITIATOR(fnic)) {
+		spin_unlock_irqrestore(&fnic->fnic_lock, fnic->lock_flags);
+		nvfnic_exch_reset(iport, tport);
+		spin_lock_irqsave(&fnic->fnic_lock, fnic->lock_flags);
 	}
 
 	if ((tport->flags & FNIC_FDLS_SCSI_REGISTERED) ||
@@ -1829,6 +1848,7 @@ static struct fnic_tport_s *fdls_create_tport(struct fnic_iport_s *iport,
 	tport->fcid = fcid;
 	tport->wwpn = wwpn;
 	tport->iport = iport;
+	INIT_LIST_HEAD(&tport->ls_req_list);
 
 	FNIC_FCS_DBG(KERN_DEBUG, fnic,
 				 "Need to setup tport timer callback");
@@ -2440,6 +2460,8 @@ static void fdls_tport_timer_callback(struct timer_list *t)
 	struct fnic *fnic = iport->fnic;
 	uint16_t oxid;
 	unsigned long flags;
+	struct fc_frame_header fchdr = {0};
+	uint8_t fcid[3];
 
 	spin_lock_irqsave(&fnic->fnic_lock, flags);
 	if (!tport->timer_pending) {
@@ -2532,6 +2554,12 @@ static void fdls_tport_timer_callback(struct timer_list *t)
 		FNIC_FCS_DBG(KERN_INFO, fnic,
 			"0x%x timeout tport 0x%x oxid 0x%x state %d\n",
 			iport->fcid, tport->fcid, oxid, tport->state);
+		if (IS_FNIC_NVME_INITIATOR(fnic)) {
+			hton24(fcid, tport->fcid);
+			FNIC_STD_SET_S_ID(fchdr, fcid);
+			FNIC_STD_SET_OX_ID(fchdr, oxid);
+			nvfnic_process_ls_abts_rsp(iport, &fchdr);
+		}
 		break;
 	}
 	spin_unlock_irqrestore(&fnic->fnic_lock, flags);
@@ -2842,6 +2870,12 @@ fdls_process_tgt_prli_rsp(struct fnic_iport_s *iport,
 				 "mismatched target zoned with FC SCSI initiator: 0x%x",
 				 tgt_fcid);
 			mismatched_tgt = true;
+		} else if (IS_FNIC_NVME_INITIATOR(fnic) &&
+			   prli_rsp->sp.spp_type != FC_TYPE_NVME) {
+			FNIC_FCS_DBG(KERN_ERR, fnic,
+				 "mismatched target zoned with NVME initiator: 0x%x",
+				 tgt_fcid);
+			mismatched_tgt = true;
 		}
 		if (mismatched_tgt) {
 			fdls_tgt_logout(iport, tport);
@@ -4853,6 +4887,8 @@ fnic_fdls_validate_and_get_frame_type(struct fnic_iport_s *iport,
 			return FNIC_FDMI_BLS_ABTS_RSP;
 		} else if (fdls_is_oxid_tgt_req(oxid)) {
 			return FNIC_TPORT_BLS_ABTS_RSP;
+		} else if (fdls_is_oxid_nvme_req(oxid)) {
+			return FNIC_LS_REQ_ABTS_RSP;
 		}
 		FNIC_FCS_DBG(KERN_INFO, fnic,
 			"Received ABTS rsp with unknown oxid(0x%x) from 0x%x. Dropping frame",
@@ -5085,6 +5121,9 @@ void fnic_fdls_recv_frame(struct fnic_iport_s *iport, void *rx_frame,
 	case FNIC_FABRIC_BLS_ABTS_RSP:
 			fdls_process_fabric_abts_rsp(iport, fchdr);
 		break;
+	case FNIC_LS_REQ_ABTS_RSP:
+		nvfnic_process_ls_abts_rsp(iport, fchdr);
+		break;
 	case FNIC_FDMI_BLS_ABTS_RSP:
 		fdls_process_fdmi_abts_rsp(iport, fchdr);
 		break;
diff --git a/drivers/scsi/fnic/fnic_fcs.c b/drivers/scsi/fnic/fnic_fcs.c
index 94b7c150c08c..b00672ef8b00 100644
--- a/drivers/scsi/fnic/fnic_fcs.c
+++ b/drivers/scsi/fnic/fnic_fcs.c
@@ -31,6 +31,11 @@ struct workqueue_struct *fnic_event_queue;
 
 static uint8_t FCOE_ALL_FCF_MAC[6] = FC_FCOE_FLOGI_MAC;
 
+static inline bool fnic_is_nvme_frame(struct fc_frame_header *fchdr)
+{
+	return (fchdr->fh_type == FC_TYPE_NVME);
+}
+
 /*
  * Internal Functions
  * This function will initialize the src_mac address to be
@@ -284,6 +289,7 @@ void fnic_handle_frame(struct work_struct *work)
 	struct fnic *fnic = container_of(work, struct fnic, frame_work);
 	struct fnic_frame_list *cur_frame, *next;
 	int fchdr_offset = 0;
+	struct fc_frame_header *fchdr;
 
 	spin_lock_irqsave(&fnic->fnic_lock, fnic->lock_flags);
 	list_for_each_entry_safe(cur_frame, next, &fnic->frame_queue, links) {
@@ -313,8 +319,14 @@ void fnic_handle_frame(struct work_struct *work)
 		fchdr_offset = (cur_frame->rx_ethhdr_stripped) ?
 			0 : FNIC_ETH_FCOE_HDRS_OFFSET;
 
-		fnic_fdls_recv_frame(&fnic->iport, cur_frame->fp,
-							 cur_frame->frame_len, fchdr_offset);
+		fchdr = (struct fc_frame_header *)((u8 *)cur_frame->fp + fchdr_offset);
+		if (IS_FNIC_NVME_INITIATOR(fnic) && fnic_is_nvme_frame(fchdr)) {
+			nvfnic_ls_rsp_recv(&fnic->iport, fchdr,
+					  cur_frame->frame_len - fchdr_offset);
+		} else {
+			fnic_fdls_recv_frame(&fnic->iport, cur_frame->fp,
+					     cur_frame->frame_len, fchdr_offset);
+		}
 
 		mempool_free(cur_frame->fp, fnic->frame_recv_pool);
 		mempool_free(cur_frame, fnic->frame_elem_pool);
@@ -614,9 +626,13 @@ int fnic_alloc_rq_frame(struct vnic_rq *rq)
 
 void fnic_free_rq_buf(struct vnic_rq *rq, struct vnic_rq_buf *buf)
 {
-	void *rq_buf = buf->os_buf;
+	void *rq_buf;
 	struct fnic *fnic = vnic_dev_priv(rq->vdev);
 
+	if (WARN_ON(!buf))
+		return;
+
+	rq_buf = buf->os_buf;
 	dma_unmap_single(&fnic->pdev->dev, buf->dma_addr, buf->len,
 			 DMA_FROM_DEVICE);
 
@@ -651,7 +667,7 @@ static int fnic_send_frame(struct fnic *fnic, void *frame, int frame_len)
 		dma_unmap_single(&fnic->pdev->dev, pa, frame_len, DMA_TO_DEVICE);
 		FNIC_FCS_DBG(KERN_INFO, fnic,
 					 "vnic work queue descriptor is not available");
-		ret = -1;
+		ret = -ENXIO;
 		goto fnic_send_frame_end;
 	}
 
@@ -685,7 +701,6 @@ fdls_send_fcoe_frame(struct fnic *fnic, void *frame, int frame_size,
 	struct fcoe_hdr *pfcoe_hdr;
 	struct fnic_frame_list *frame_elem;
 	int len = frame_size;
-	int ret;
 	struct fc_frame_header *fchdr = (struct fc_frame_header *) (frame +
 			FNIC_ETH_FCOE_HDRS_OFFSET);
 
@@ -723,8 +738,7 @@ fdls_send_fcoe_frame(struct fnic *fnic, void *frame, int frame_size,
 
 	fnic_debug_dump_fc_frame(fnic, fchdr, frame_size, "Outgoing");
 
-	ret = fnic_send_frame(fnic, frame, len);
-	return ret;
+	return fnic_send_frame(fnic, frame, len);
 }
 
 int fnic_send_fcoe_frame(struct fnic_iport_s *iport, void *frame,
@@ -872,6 +886,9 @@ static void fnic_wq_complete_frame_send(struct vnic_wq *wq,
 {
 	struct fnic *fnic = vnic_dev_priv(wq->vdev);
 
+	if (WARN_ON(!buf))
+		return;
+
 	dma_unmap_single(&fnic->pdev->dev, buf->dma_addr, buf->len,
 			 DMA_TO_DEVICE);
 	mempool_free(buf->os_buf, fnic->frame_pool);
@@ -914,6 +931,9 @@ void fnic_free_wq_buf(struct vnic_wq *wq, struct vnic_wq_buf *buf)
 {
 	struct fnic *fnic = vnic_dev_priv(wq->vdev);
 
+	if (WARN_ON(!buf))
+		return;
+
 	dma_unmap_single(&fnic->pdev->dev, buf->dma_addr, buf->len,
 			 DMA_TO_DEVICE);
 
-- 
2.47.1