IB/hfi1: Rework AIP and VNIC dummy netdev usage

All other users of the dummy netdevice embed the netdev in other
structures:

init_dummy_netdev(&mal->dummy_dev);
init_dummy_netdev(&eth->dummy_dev);
init_dummy_netdev(&ar->napi_dev);
init_dummy_netdev(&irq_grp->napi_ndev);
init_dummy_netdev(&wil->napi_ndev);
init_dummy_netdev(&trans_pcie->napi_dev);
init_dummy_netdev(&dev->napi_dev);
init_dummy_netdev(&bus->mux_dev);

The AIP and VNIC implementation turns that model inside out and used a
kfree() to free what appears to be a netdev struct when in reality, it is
a struct that enbodies the rx state as well as the dummy netdev used to
support napi_poll across disparate receive contexts.  The relationship is
infered by the odd allocation:

	const int netdev_size = sizeof(*dd->dummy_netdev) +
		sizeof(struct hfi1_netdev_priv);
	<snip>
	dd->dummy_netdev = kcalloc_node(1, netdev_size, GFP_KERNEL, dd->node);

Correct the issue by:
- Correctly naming the alloc and free functions
- Renaming hfi1_netdev_priv to hfi1_netdev_rx
- Replacing dd dummy_netdev with a netdev_rx pointer
- Embedding the net_device in hfi1_netdev_rx
- Moving the init_dummy_netdev to the alloc routine
- Adjusting wrappers to fit the new model

Fixes: 6991abc ("IB/hfi1: Add functions to receive accelerated ipoib packets")
Link: https://lore.kernel.org/r/1617026056-50483-11-git-send-email-dennis.dalessandro@cornelisnetworks.com
Reviewed-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@cornelisnetworks.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@cornelisnetworks.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

drivers/infiniband/hw/hfi1/chip.c

@@ -15243,8 +15243,8 @@ int hfi1_init_dd(struct hfi1_devdata *dd)
 		 (dd->revision >> CCE_REVISION_SW_SHIFT)
 		    & CCE_REVISION_SW_MASK);
 
-	/* alloc netdev data */
-	ret = hfi1_netdev_alloc(dd);
+	/* alloc VNIC/AIP rx data */
+	ret = hfi1_alloc_rx(dd);
 	if (ret)
 		goto bail_cleanup;
 
@@ -15348,7 +15348,7 @@ int hfi1_init_dd(struct hfi1_devdata *dd)
 	hfi1_comp_vectors_clean_up(dd);
 	msix_clean_up_interrupts(dd);
 bail_cleanup:
-	hfi1_netdev_free(dd);
+	hfi1_free_rx(dd);
 	hfi1_pcie_ddcleanup(dd);
 bail_free:
 	hfi1_free_devdata(dd);

drivers/infiniband/hw/hfi1/hfi.h

@@ -69,7 +69,6 @@
 #include <rdma/ib_hdrs.h>
 #include <rdma/opa_addr.h>
 #include <linux/rhashtable.h>
-#include <linux/netdevice.h>
 #include <rdma/rdma_vt.h>
 
 #include "chip_registers.h"
@@ -1060,6 +1059,7 @@ struct sdma_vl_map;
 #define SERIAL_MAX 16 /* length of the serial number */
 
 typedef int (*send_routine)(struct rvt_qp *, struct hfi1_pkt_state *, u64);
+struct hfi1_netdev_rx;
 struct hfi1_devdata {
 	struct hfi1_ibdev verbs_dev;     /* must be first */
 	/* pointers to related structs for this device */
@@ -1402,7 +1402,7 @@ struct hfi1_devdata {
 	/* Lock to protect IRQ SRC register access */
 	spinlock_t irq_src_lock;
 	int vnic_num_vports;
-	struct net_device *dummy_netdev;
+	struct hfi1_netdev_rx *netdev_rx;
 
 	/* Keeps track of IPoIB RSM rule users */
 	atomic_t ipoib_rsm_usr_num;

drivers/infiniband/hw/hfi1/init.c

@@ -1767,7 +1767,7 @@ static void remove_one(struct pci_dev *pdev)
 	hfi1_unregister_ib_device(dd);
 
 	/* free netdev data */
-	hfi1_netdev_free(dd);
+	hfi1_free_rx(dd);
 
 	/*
 	 * Disable the IB link, disable interrupts on the device,

drivers/infiniband/hw/hfi1/netdev.h

@@ -14,15 +14,14 @@
 
 /**
  * struct hfi1_netdev_rxq - Receive Queue for HFI
- * dummy netdev. Both IPoIB and VNIC netdevices will be working on
- * top of this device.
+ * Both IPoIB and VNIC netdevices will be working on the rx abstraction.
  * @napi: napi object
- * @priv: ptr to netdev_priv
+ * @rx: ptr to netdev_rx
  * @rcd:  ptr to receive context data
  */
 struct hfi1_netdev_rxq {
 	struct napi_struct napi;
-	struct hfi1_netdev_priv *priv;
+	struct hfi1_netdev_rx *rx;
 	struct hfi1_ctxtdata *rcd;
 };
 
@@ -36,7 +35,8 @@ struct hfi1_netdev_rxq {
 #define NUM_NETDEV_MAP_ENTRIES HFI1_MAX_NETDEV_CTXTS
 
 /**
- * struct hfi1_netdev_priv: data required to setup and run HFI netdev.
+ * struct hfi1_netdev_rx: data required to setup and run HFI netdev.
+ * @rx_napi:	the dummy netdevice to support "polling" the receive contexts
  * @dd:		hfi1_devdata
  * @rxq:	pointer to dummy netdev receive queues.
  * @num_rx_q:	number of receive queues
@@ -48,7 +48,8 @@ struct hfi1_netdev_rxq {
  * @netdevs:	atomic counter of netdevs using dummy netdev.
  *		When 0 receive queues will be freed.
  */
-struct hfi1_netdev_priv {
+struct hfi1_netdev_rx {
+	struct net_device rx_napi;
 	struct hfi1_devdata *dd;
 	struct hfi1_netdev_rxq *rxq;
 	int num_rx_q;
@@ -60,42 +61,28 @@ struct hfi1_netdev_priv {
 	atomic_t netdevs;
 };
 
-static inline
-struct hfi1_netdev_priv *hfi1_netdev_priv(struct net_device *dev)
-{
-	return (struct hfi1_netdev_priv *)&dev[1];
-}
-
 static inline
 int hfi1_netdev_ctxt_count(struct hfi1_devdata *dd)
 {
-	struct hfi1_netdev_priv *priv = hfi1_netdev_priv(dd->dummy_netdev);
-
-	return priv->num_rx_q;
+	return dd->netdev_rx->num_rx_q;
 }
 
 static inline
 struct hfi1_ctxtdata *hfi1_netdev_get_ctxt(struct hfi1_devdata *dd, int ctxt)
 {
-	struct hfi1_netdev_priv *priv = hfi1_netdev_priv(dd->dummy_netdev);
-
-	return priv->rxq[ctxt].rcd;
+	return dd->netdev_rx->rxq[ctxt].rcd;
 }
 
 static inline
 int hfi1_netdev_get_free_rmt_idx(struct hfi1_devdata *dd)
 {
-	struct hfi1_netdev_priv *priv = hfi1_netdev_priv(dd->dummy_netdev);
-
-	return priv->rmt_start;
+	return dd->netdev_rx->rmt_start;
 }
 
 static inline
 void hfi1_netdev_set_free_rmt_idx(struct hfi1_devdata *dd, int rmt_idx)
 {
-	struct hfi1_netdev_priv *priv = hfi1_netdev_priv(dd->dummy_netdev);
-
-	priv->rmt_start = rmt_idx;
+	dd->netdev_rx->rmt_start = rmt_idx;
 }
 
 u32 hfi1_num_netdev_contexts(struct hfi1_devdata *dd, u32 available_contexts,
@@ -105,8 +92,8 @@ void hfi1_netdev_enable_queues(struct hfi1_devdata *dd);
 void hfi1_netdev_disable_queues(struct hfi1_devdata *dd);
 int hfi1_netdev_rx_init(struct hfi1_devdata *dd);
 int hfi1_netdev_rx_destroy(struct hfi1_devdata *dd);
-int hfi1_netdev_alloc(struct hfi1_devdata *dd);
-void hfi1_netdev_free(struct hfi1_devdata *dd);
+int hfi1_alloc_rx(struct hfi1_devdata *dd);
+void hfi1_free_rx(struct hfi1_devdata *dd);
 int hfi1_netdev_add_data(struct hfi1_devdata *dd, int id, void *data);
 void *hfi1_netdev_remove_data(struct hfi1_devdata *dd, int id);
 void *hfi1_netdev_get_data(struct hfi1_devdata *dd, int id);