IB/hfi1: VNIC SDMA support

HFI1 VNIC SDMA support enables transmission of VNIC packets over SDMA.
Map VNIC queues to SDMA engines and support halting and wakeup of the
VNIC queues.

Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Niranjana Vishwanathapura <niranjana.vishwanathapura@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

drivers/infiniband/hw/hfi1/Makefile

@@ -12,7 +12,7 @@ hfi1-y := affinity.o chip.o device.o driver.o efivar.o \
 	init.o intr.o mad.o mmu_rb.o pcie.o pio.o pio_copy.o platform.o \
 	qp.o qsfp.o rc.o ruc.o sdma.o sysfs.o trace.o \
 	uc.o ud.o user_exp_rcv.o user_pages.o user_sdma.o verbs.o \
-	verbs_txreq.o vnic_main.o
+	verbs_txreq.o vnic_main.o vnic_sdma.o
 hfi1-$(CONFIG_DEBUG_FS) += debugfs.o
 
 CFLAGS_trace.o = -I$(src)

drivers/infiniband/hw/hfi1/hfi.h

@@ -834,6 +834,7 @@ struct hfi1_asic_data {
 /* Virtual NIC information */
 struct hfi1_vnic_data {
 	struct hfi1_ctxtdata *ctxt[HFI1_NUM_VNIC_CTXT];
+	struct kmem_cache *txreq_cache;
 	u8 num_vports;
 	struct idr vesw_idr;
 	u8 rmt_start;

drivers/infiniband/hw/hfi1/init.c

@@ -681,6 +681,7 @@ int hfi1_init(struct hfi1_devdata *dd, int reinit)
 	dd->process_pio_send = hfi1_verbs_send_pio;
 	dd->process_dma_send = hfi1_verbs_send_dma;
 	dd->pio_inline_send = pio_copy;
+	dd->process_vnic_dma_send = hfi1_vnic_send_dma;
 
 	if (is_ax(dd)) {
 		atomic_set(&dd->drop_packet, DROP_PACKET_ON);

drivers/infiniband/hw/hfi1/vnic.h

@@ -49,6 +49,7 @@
 
 #include <rdma/opa_vnic.h>
 #include "hfi.h"
+#include "sdma.h"
 
 #define HFI1_VNIC_MAX_TXQ     16
 #define HFI1_VNIC_MAX_PAD     12
@@ -84,6 +85,26 @@
 
 #define HFI1_VNIC_MAX_QUEUE 16
 
+/**
+ * struct hfi1_vnic_sdma - VNIC per Tx ring SDMA information
+ * @dd - device data pointer
+ * @sde - sdma engine
+ * @vinfo - vnic info pointer
+ * @wait - iowait structure
+ * @stx - sdma tx request
+ * @state - vnic Tx ring SDMA state
+ * @q_idx - vnic Tx queue index
+ */
+struct hfi1_vnic_sdma {
+	struct hfi1_devdata *dd;
+	struct sdma_engine  *sde;
+	struct hfi1_vnic_vport_info *vinfo;
+	struct iowait wait;
+	struct sdma_txreq stx;
+	unsigned int state;
+	u8 q_idx;
+};
+
 /**
  * struct hfi1_vnic_rx_queue - HFI1 VNIC receive queue
  * @idx: queue index
@@ -111,6 +132,7 @@ struct hfi1_vnic_rx_queue {
  * @vesw_id: virtual switch id
  * @rxq: Array of receive queues
  * @stats: per queue stats
+ * @sdma: VNIC SDMA structure per TXQ
  */
 struct hfi1_vnic_vport_info {
 	struct hfi1_devdata *dd;
@@ -126,6 +148,7 @@ struct hfi1_vnic_vport_info {
 	struct hfi1_vnic_rx_queue rxq[HFI1_NUM_VNIC_CTXT];
 
 	struct opa_vnic_stats  stats[HFI1_VNIC_MAX_QUEUE];
+	struct hfi1_vnic_sdma  sdma[HFI1_VNIC_MAX_TXQ];
 };
 
 #define v_dbg(format, arg...) \
@@ -138,8 +161,13 @@ struct hfi1_vnic_vport_info {
 /* vnic hfi1 internal functions */
 void hfi1_vnic_setup(struct hfi1_devdata *dd);
 void hfi1_vnic_cleanup(struct hfi1_devdata *dd);
+int hfi1_vnic_txreq_init(struct hfi1_devdata *dd);
+void hfi1_vnic_txreq_deinit(struct hfi1_devdata *dd);
 
 void hfi1_vnic_bypass_rcv(struct hfi1_packet *packet);
+void hfi1_vnic_sdma_init(struct hfi1_vnic_vport_info *vinfo);
+bool hfi1_vnic_sdma_write_avail(struct hfi1_vnic_vport_info *vinfo,
+				u8 q_idx);
 
 /* vnic rdma netdev operations */
 struct net_device *hfi1_vnic_alloc_rn(struct ib_device *device,

drivers/infiniband/hw/hfi1/vnic_main.c

@@ -406,6 +406,10 @@ static void hfi1_vnic_maybe_stop_tx(struct hfi1_vnic_vport_info *vinfo,
 				    u8 q_idx)
 {
 	netif_stop_subqueue(vinfo->netdev, q_idx);
+	if (!hfi1_vnic_sdma_write_avail(vinfo, q_idx))
+		return;
+
+	netif_start_subqueue(vinfo->netdev, q_idx);
 }
 
 static netdev_tx_t hfi1_netdev_start_xmit(struct sk_buff *skb,
@@ -477,7 +481,13 @@ static u16 hfi1_vnic_select_queue(struct net_device *netdev,
 				  void *accel_priv,
 				  select_queue_fallback_t fallback)
 {
-	return 0;
+	struct hfi1_vnic_vport_info *vinfo = opa_vnic_dev_priv(netdev);
+	struct opa_vnic_skb_mdata *mdata;
+	struct sdma_engine *sde;
+
+	mdata = (struct opa_vnic_skb_mdata *)skb->data;
+	sde = sdma_select_engine_vl(vinfo->dd, mdata->entropy, mdata->vl);
+	return sde->this_idx;
 }
 
 /* hfi1_vnic_decap_skb - strip OPA header from the skb (ethernet) packet */
@@ -733,8 +743,13 @@ static int hfi1_vnic_init(struct hfi1_vnic_vport_info *vinfo)
 	int i, rc = 0;
 
 	mutex_lock(&hfi1_mutex);
-	if (!dd->vnic.num_vports)
+	if (!dd->vnic.num_vports) {
+		rc = hfi1_vnic_txreq_init(dd);
+		if (rc)
+			goto txreq_fail;
+
 		dd->vnic.msix_idx = dd->first_dyn_msix_idx;
+	}
 
 	for (i = dd->vnic.num_ctxt; i < vinfo->num_rx_q; i++) {
 		rc = hfi1_vnic_allot_ctxt(dd, &dd->vnic.ctxt[i]);
@@ -762,7 +777,11 @@ static int hfi1_vnic_init(struct hfi1_vnic_vport_info *vinfo)
 	}
 
 	dd->vnic.num_vports++;
+	hfi1_vnic_sdma_init(vinfo);
 alloc_fail:
+	if (!dd->vnic.num_vports)
+		hfi1_vnic_txreq_deinit(dd);
+txreq_fail:
 	mutex_unlock(&hfi1_mutex);
 	return rc;
 }
@@ -780,6 +799,7 @@ static void hfi1_vnic_deinit(struct hfi1_vnic_vport_info *vinfo)
 		}
 		hfi1_deinit_vnic_rsm(dd);
 		dd->vnic.num_ctxt = 0;
+		hfi1_vnic_txreq_deinit(dd);
 	}
 	mutex_unlock(&hfi1_mutex);
 }