IB/qib: Remove qpn, qp tables and related variables from qib

This patch removes the private queue pair structure and the table which
holds the queue pair numbers in favor of using what is provided by rdmavt.
Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Harish Chegondi <harish.chegondi@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

drivers/infiniband/hw/qib/qib_qp.c

@@ -42,25 +42,31 @@
 
 #include "qib.h"
 
-#define BITS_PER_PAGE           (PAGE_SIZE*BITS_PER_BYTE)
-#define BITS_PER_PAGE_MASK      (BITS_PER_PAGE-1)
+/*
+ * mask field which was present in now deleted qib_qpn_table
+ * is not present in rvt_qpn_table. Defining the same field
+ * as qpt_mask here instead of adding the mask field to
+ * rvt_qpn_table.
+ */
+static u16 qpt_mask;
 
-static inline unsigned mk_qpn(struct qib_qpn_table *qpt,
-			      struct qpn_map *map, unsigned off)
+static inline unsigned mk_qpn(struct rvt_qpn_table *qpt,
+			      struct rvt_qpn_map *map, unsigned off)
 {
-	return (map - qpt->map) * BITS_PER_PAGE + off;
+	return (map - qpt->map) * RVT_BITS_PER_PAGE + off;
 }
 
-static inline unsigned find_next_offset(struct qib_qpn_table *qpt,
-					struct qpn_map *map, unsigned off,
+static inline unsigned find_next_offset(struct rvt_qpn_table *qpt,
+					struct rvt_qpn_map *map, unsigned off,
 					unsigned n)
 {
-	if (qpt->mask) {
+	if (qpt_mask) {
 		off++;
-		if (((off & qpt->mask) >> 1) >= n)
-			off = (off | qpt->mask) + 2;
-	} else
-		off = find_next_zero_bit(map->page, BITS_PER_PAGE, off);
+		if (((off & qpt_mask) >> 1) >= n)
+			off = (off | qpt_mask) + 2;
+	} else {
+		off = find_next_zero_bit(map->page, RVT_BITS_PER_PAGE, off);
+	}
 	return off;
 }
 
@@ -101,7 +107,7 @@ static u32 credit_table[31] = {
 	32768                   /* 1E */
 };
 
-static void get_map_page(struct qib_qpn_table *qpt, struct qpn_map *map,
+static void get_map_page(struct rvt_qpn_table *qpt, struct rvt_qpn_map *map,
 			 gfp_t gfp)
 {
 	unsigned long page = get_zeroed_page(gfp);
@@ -122,11 +128,11 @@ static void get_map_page(struct qib_qpn_table *qpt, struct qpn_map *map,
  * Allocate the next available QPN or
  * zero/one for QP type IB_QPT_SMI/IB_QPT_GSI.
  */
-static int alloc_qpn(struct qib_devdata *dd, struct qib_qpn_table *qpt,
+static int alloc_qpn(struct qib_devdata *dd, struct rvt_qpn_table *qpt,
 		     enum ib_qp_type type, u8 port, gfp_t gfp)
 {
 	u32 i, offset, max_scan, qpn;
-	struct qpn_map *map;
+	struct rvt_qpn_map *map;
 	u32 ret;
 
 	if (type == IB_QPT_SMI || type == IB_QPT_GSI) {
@@ -144,12 +150,12 @@ static int alloc_qpn(struct qib_devdata *dd, struct qib_qpn_table *qpt,
 	}
 
 	qpn = qpt->last + 2;
-	if (qpn >= QPN_MAX)
+	if (qpn >= RVT_QPN_MAX)
 		qpn = 2;
-	if (qpt->mask && ((qpn & qpt->mask) >> 1) >= dd->n_krcv_queues)
-		qpn = (qpn | qpt->mask) + 2;
-	offset = qpn & BITS_PER_PAGE_MASK;
-	map = &qpt->map[qpn / BITS_PER_PAGE];
+	if (qpt_mask && ((qpn & qpt_mask) >> 1) >= dd->n_krcv_queues)
+		qpn = (qpn | qpt_mask) + 2;
+	offset = qpn & RVT_BITS_PER_PAGE_MASK;
+	map = &qpt->map[qpn / RVT_BITS_PER_PAGE];
 	max_scan = qpt->nmaps - !offset;
 	for (i = 0;;) {
 		if (unlikely(!map->page)) {
@@ -174,14 +180,14 @@ static int alloc_qpn(struct qib_devdata *dd, struct qib_qpn_table *qpt,
 			 * We just need to be sure we don't loop
 			 * forever.
 			 */
-		} while (offset < BITS_PER_PAGE && qpn < QPN_MAX);
+		} while (offset < RVT_BITS_PER_PAGE && qpn < RVT_QPN_MAX);
 		/*
 		 * In order to keep the number of pages allocated to a
 		 * minimum, we scan the all existing pages before increasing
 		 * the size of the bitmap table.
 		 */
 		if (++i > max_scan) {
-			if (qpt->nmaps == QPNMAP_ENTRIES)
+			if (qpt->nmaps == RVT_QPNMAP_ENTRIES)
 				break;
 			map = &qpt->map[qpt->nmaps++];
 			offset = 0;
@@ -201,19 +207,19 @@ static int alloc_qpn(struct qib_devdata *dd, struct qib_qpn_table *qpt,
 	return ret;
 }
 
-static void free_qpn(struct qib_qpn_table *qpt, u32 qpn)
+static void free_qpn(struct rvt_qpn_table *qpt, u32 qpn)
 {
-	struct qpn_map *map;
+	struct rvt_qpn_map *map;
 
-	map = qpt->map + qpn / BITS_PER_PAGE;
+	map = qpt->map + qpn / RVT_BITS_PER_PAGE;
 	if (map->page)
-		clear_bit(qpn & BITS_PER_PAGE_MASK, map->page);
+		clear_bit(qpn & RVT_BITS_PER_PAGE_MASK, map->page);
 }
 
 static inline unsigned qpn_hash(struct qib_ibdev *dev, u32 qpn)
 {
 	return jhash_1word(qpn, dev->qp_rnd) &
-		(dev->qp_table_size - 1);
+		(dev->rdi.qp_dev->qp_table_size - 1);
 }
 
 
@@ -228,18 +234,18 @@ static void insert_qp(struct qib_ibdev *dev, struct rvt_qp *qp)
 	unsigned n = qpn_hash(dev, qp->ibqp.qp_num);
 
 	atomic_inc(&qp->refcount);
-	spin_lock_irqsave(&dev->qpt_lock, flags);
+	spin_lock_irqsave(&dev->rdi.qp_dev->qpt_lock, flags);
 
 	if (qp->ibqp.qp_num == 0)
 		rcu_assign_pointer(ibp->rvp.qp[0], qp);
 	else if (qp->ibqp.qp_num == 1)
 		rcu_assign_pointer(ibp->rvp.qp[1], qp);
 	else {
-		qp->next = dev->qp_table[n];
-		rcu_assign_pointer(dev->qp_table[n], qp);
+		qp->next = dev->rdi.qp_dev->qp_table[n];
+		rcu_assign_pointer(dev->rdi.qp_dev->qp_table[n], qp);
 	}
 
-	spin_unlock_irqrestore(&dev->qpt_lock, flags);
+	spin_unlock_irqrestore(&dev->rdi.qp_dev->qpt_lock, flags);
 }
 
 /*
@@ -252,34 +258,36 @@ static void remove_qp(struct qib_ibdev *dev, struct rvt_qp *qp)
 	unsigned n = qpn_hash(dev, qp->ibqp.qp_num);
 	unsigned long flags;
 	int removed = 1;
+	spinlock_t *qpt_lock_ptr; /* Pointer to make checkpatch happy */
 
-	spin_lock_irqsave(&dev->qpt_lock, flags);
+	spin_lock_irqsave(&dev->rdi.qp_dev->qpt_lock, flags);
 
+	qpt_lock_ptr = &dev->rdi.qp_dev->qpt_lock;
 	if (rcu_dereference_protected(ibp->rvp.qp[0],
-				      lockdep_is_held(&dev->qpt_lock)) == qp) {
+				      lockdep_is_held(qpt_lock_ptr)) == qp) {
 		RCU_INIT_POINTER(ibp->rvp.qp[0], NULL);
 	} else if (rcu_dereference_protected(ibp->rvp.qp[1],
-			lockdep_is_held(&dev->qpt_lock)) == qp) {
+			lockdep_is_held(&dev->rdi.qp_dev->qpt_lock)) == qp) {
 		RCU_INIT_POINTER(ibp->rvp.qp[1], NULL);
 	} else {
 		struct rvt_qp *q;
 		struct rvt_qp __rcu **qpp;
 
 		removed = 0;
-		qpp = &dev->qp_table[n];
+		qpp = &dev->rdi.qp_dev->qp_table[n];
 		for (; (q = rcu_dereference_protected(*qpp,
-				lockdep_is_held(&dev->qpt_lock))) != NULL;
+				lockdep_is_held(qpt_lock_ptr))) != NULL;
 				qpp = &q->next)
 			if (q == qp) {
 				RCU_INIT_POINTER(*qpp,
 					rcu_dereference_protected(qp->next,
-					 lockdep_is_held(&dev->qpt_lock)));
+					 lockdep_is_held(qpt_lock_ptr)));
 				removed = 1;
 				break;
 			}
 	}
 
-	spin_unlock_irqrestore(&dev->qpt_lock, flags);
+	spin_unlock_irqrestore(&dev->rdi.qp_dev->qpt_lock, flags);
 	if (removed) {
 		synchronize_rcu();
 		atomic_dec(&qp->refcount);
@@ -299,6 +307,7 @@ unsigned qib_free_all_qps(struct qib_devdata *dd)
 	unsigned long flags;
 	struct rvt_qp *qp;
 	unsigned n, qp_inuse = 0;
+	spinlock_t *qpt_lock_ptr; /* Pointer to make checkpatch happy */
 
 	for (n = 0; n < dd->num_pports; n++) {
 		struct qib_ibport *ibp = &dd->pport[n].ibport_data;
@@ -313,17 +322,18 @@ unsigned qib_free_all_qps(struct qib_devdata *dd)
 		rcu_read_unlock();
 	}
 
-	spin_lock_irqsave(&dev->qpt_lock, flags);
-	for (n = 0; n < dev->qp_table_size; n++) {
-		qp = rcu_dereference_protected(dev->qp_table[n],
-			lockdep_is_held(&dev->qpt_lock));
-		RCU_INIT_POINTER(dev->qp_table[n], NULL);
+	spin_lock_irqsave(&dev->rdi.qp_dev->qpt_lock, flags);
+	qpt_lock_ptr = &dev->rdi.qp_dev->qpt_lock;
+	for (n = 0; n < dev->rdi.qp_dev->qp_table_size; n++) {
+		qp = rcu_dereference_protected(dev->rdi.qp_dev->qp_table[n],
+					       lockdep_is_held(qpt_lock_ptr));
+		RCU_INIT_POINTER(dev->rdi.qp_dev->qp_table[n], NULL);
 
 		for (; qp; qp = rcu_dereference_protected(qp->next,
-					lockdep_is_held(&dev->qpt_lock)))
+					lockdep_is_held(qpt_lock_ptr)))
 			qp_inuse++;
 	}
-	spin_unlock_irqrestore(&dev->qpt_lock, flags);
+	spin_unlock_irqrestore(&dev->rdi.qp_dev->qpt_lock, flags);
 	synchronize_rcu();
 
 	return qp_inuse;
@@ -353,7 +363,7 @@ struct rvt_qp *qib_lookup_qpn(struct qib_ibport *ibp, u32 qpn)
 		struct qib_ibdev *dev = &ppd_from_ibp(ibp)->dd->verbs_dev;
 		unsigned n = qpn_hash(dev, qpn);
 
-		for (qp = rcu_dereference(dev->qp_table[n]); qp;
+		for (qp = rcu_dereference(dev->rdi.qp_dev->qp_table[n]); qp;
 			qp = rcu_dereference(qp->next))
 			if (qp->ibqp.qp_num == qpn) {
 				atomic_inc(&qp->refcount);
@@ -1121,8 +1131,8 @@ struct ib_qp *qib_create_qp(struct ib_pd *ibpd,
 			qp->s_flags = QIB_S_SIGNAL_REQ_WR;
 		dev = to_idev(ibpd->device);
 		dd = dd_from_dev(dev);
-		err = alloc_qpn(dd, &dev->qpn_table, init_attr->qp_type,
-				init_attr->port_num, gfp);
+		err = alloc_qpn(dd, &dev->rdi.qp_dev->qpn_table,
+				init_attr->qp_type, init_attr->port_num, gfp);
 		if (err < 0) {
 			ret = ERR_PTR(err);
 			vfree(qp->r_rq.wq);
@@ -1199,7 +1209,7 @@ struct ib_qp *qib_create_qp(struct ib_pd *ibpd,
 		kref_put(&qp->ip->ref, rvt_release_mmap_info);
 	else
 		vfree(qp->r_rq.wq);
-	free_qpn(&dev->qpn_table, qp->ibqp.qp_num);
+	free_qpn(&dev->rdi.qp_dev->qpn_table, qp->ibqp.qp_num);
 bail_qp:
 	kfree(priv->s_hdr);
 	kfree(priv);
@@ -1250,7 +1260,7 @@ int qib_destroy_qp(struct ib_qp *ibqp)
 		spin_unlock_irq(&qp->s_lock);
 
 	/* all user's cleaned up, mark it available */
-	free_qpn(&dev->qpn_table, qp->ibqp.qp_num);
+	free_qpn(&dev->rdi.qp_dev->qpn_table, qp->ibqp.qp_num);
 	spin_lock(&dev->n_qps_lock);
 	dev->n_qps_allocated--;
 	spin_unlock(&dev->n_qps_lock);
@@ -1270,19 +1280,19 @@ int qib_destroy_qp(struct ib_qp *ibqp)
  * qib_init_qpn_table - initialize the QP number table for a device
  * @qpt: the QPN table
  */
-void qib_init_qpn_table(struct qib_devdata *dd, struct qib_qpn_table *qpt)
+void qib_init_qpn_table(struct qib_devdata *dd, struct rvt_qpn_table *qpt)
 {
 	spin_lock_init(&qpt->lock);
 	qpt->last = 1;          /* start with QPN 2 */
 	qpt->nmaps = 1;
-	qpt->mask = dd->qpn_mask;
+	qpt_mask = dd->qpn_mask;
 }
 
 /**
  * qib_free_qpn_table - free the QP number table for a device
  * @qpt: the QPN table
  */
-void qib_free_qpn_table(struct qib_qpn_table *qpt)
+void qib_free_qpn_table(struct rvt_qpn_table *qpt)
 {
 	int i;
 
@@ -1361,11 +1371,11 @@ int qib_qp_iter_next(struct qib_qp_iter *iter)
 	struct rvt_qp *pqp = iter->qp;
 	struct rvt_qp *qp;
 
-	for (; n < dev->qp_table_size; n++) {
+	for (; n < dev->rdi.qp_dev->qp_table_size; n++) {
 		if (pqp)
 			qp = rcu_dereference(pqp->next);
 		else
-			qp = rcu_dereference(dev->qp_table[n]);
+			qp = rcu_dereference(dev->rdi.qp_dev->qp_table[n]);
 		pqp = qp;
 		if (qp) {
 			iter->qp = qp;

drivers/infiniband/hw/qib/qib_verbs.c

@@ -1946,24 +1946,29 @@ int qib_register_ib_device(struct qib_devdata *dd)
 	unsigned i, ctxt;
 	int ret;
 
-	dev->qp_table_size = ib_qib_qp_table_size;
+	/* allocate parent object */
+	dev->rdi.qp_dev = kzalloc(sizeof(*dev->rdi.qp_dev), GFP_KERNEL);
+	if (!dev->rdi.qp_dev)
+		return -ENOMEM;
+	dev->rdi.qp_dev->qp_table_size = ib_qib_qp_table_size;
+	dev->rdi.qp_dev->qp_table_bits = ilog2(ib_qib_qp_table_size);
 	get_random_bytes(&dev->qp_rnd, sizeof(dev->qp_rnd));
-	dev->qp_table = kmalloc_array(
-				dev->qp_table_size,
-				sizeof(*dev->qp_table),
+	dev->rdi.qp_dev->qp_table = kmalloc_array(
+				dev->rdi.qp_dev->qp_table_size,
+				sizeof(*dev->rdi.qp_dev->qp_table),
 				GFP_KERNEL);
-	if (!dev->qp_table) {
+	if (!dev->rdi.qp_dev->qp_table) {
 		ret = -ENOMEM;
 		goto err_qpt;
 	}
-	for (i = 0; i < dev->qp_table_size; i++)
-		RCU_INIT_POINTER(dev->qp_table[i], NULL);
+	for (i = 0; i < dev->rdi.qp_dev->qp_table_size; i++)
+		RCU_INIT_POINTER(dev->rdi.qp_dev->qp_table[i], NULL);
 
 	for (i = 0; i < dd->num_pports; i++)
 		init_ibport(ppd + i);
 
 	/* Only need to initialize non-zero fields. */
-	spin_lock_init(&dev->qpt_lock);
+	spin_lock_init(&dev->rdi.qp_dev->qpt_lock);
 	spin_lock_init(&dev->n_cqs_lock);
 	spin_lock_init(&dev->n_qps_lock);
 	spin_lock_init(&dev->n_srqs_lock);
@@ -1972,7 +1977,7 @@ int qib_register_ib_device(struct qib_devdata *dd)
 	dev->mem_timer.function = mem_timer;
 	dev->mem_timer.data = (unsigned long) dev;
 
-	qib_init_qpn_table(dd, &dev->qpn_table);
+	qib_init_qpn_table(dd, &dev->rdi.qp_dev->qpn_table);
 
 	INIT_LIST_HEAD(&dev->piowait);
 	INIT_LIST_HEAD(&dev->dmawait);
@@ -2159,7 +2164,7 @@ int qib_register_ib_device(struct qib_devdata *dd)
 					sizeof(struct qib_pio_header),
 				  dev->pio_hdrs, dev->pio_hdrs_phys);
 err_hdrs:
-	kfree(dev->qp_table);
+	kfree(dev->rdi.qp_dev->qp_table);
 err_qpt:
 	qib_dev_err(dd, "cannot register verbs: %d!\n", -ret);
 bail:
@@ -2192,7 +2197,7 @@ void qib_unregister_ib_device(struct qib_devdata *dd)
 			    qps_inuse);
 
 	del_timer_sync(&dev->mem_timer);
-	qib_free_qpn_table(&dev->qpn_table);
+	qib_free_qpn_table(&dev->rdi.qp_dev->qpn_table);
 	while (!list_empty(&dev->txreq_free)) {
 		struct list_head *l = dev->txreq_free.next;
 		struct qib_verbs_txreq *tx;
@@ -2206,7 +2211,7 @@ void qib_unregister_ib_device(struct qib_devdata *dd)
 				  dd->pport->sdma_descq_cnt *
 					sizeof(struct qib_pio_header),
 				  dev->pio_hdrs, dev->pio_hdrs_phys);
-	kfree(dev->qp_table);
+	kfree(dev->rdi.qp_dev->qp_table);
 }
 
 /*

drivers/infiniband/hw/qib/qib_verbs.h

@@ -55,9 +55,6 @@ struct qib_verbs_txreq;
 #define QIB_MAX_RDMA_ATOMIC     16
 #define QIB_GUIDS_PER_PORT	5
 
-#define QPN_MAX                 (1 << 24)
-#define QPNMAP_ENTRIES          (QPN_MAX / PAGE_SIZE / BITS_PER_BYTE)
-
 /*
  * Increment this value if any changes that break userspace ABI
  * compatibility are made.
@@ -364,26 +361,6 @@ static inline struct rvt_rwqe *get_rwqe_ptr(struct rvt_rq *rq, unsigned n)
 		  rq->max_sge * sizeof(struct ib_sge)) * n);
 }
 
-/*
- * QPN-map pages start out as NULL, they get allocated upon
- * first use and are never deallocated. This way,
- * large bitmaps are not allocated unless large numbers of QPs are used.
- */
-struct qpn_map {
-	void *page;
-};
-
-struct qib_qpn_table {
-	spinlock_t lock; /* protect changes in this struct */
-	unsigned flags;         /* flags for QP0/1 allocated for each port */
-	u32 last;               /* last QP number allocated */
-	u32 nmaps;              /* size of the map table */
-	u16 limit;
-	u16 mask;
-	/* bit map of free QP numbers other than 0/1 */
-	struct qpn_map map[QPNMAP_ENTRIES];
-};
-
 struct qib_opcode_stats {
 	u64 n_packets;          /* number of packets */
 	u64 n_bytes;            /* total number of bytes */
@@ -429,21 +406,15 @@ struct qib_ibport {
 struct qib_ibdev {
 	struct rvt_dev_info rdi;
 
-	/* QP numbers are shared by all IB ports */
-	struct qib_qpn_table qpn_table;
 	struct list_head piowait;       /* list for wait PIO buf */
 	struct list_head dmawait;	/* list for wait DMA */
 	struct list_head txwait;        /* list for wait qib_verbs_txreq */
 	struct list_head memwait;       /* list for wait kernel memory */
 	struct list_head txreq_free;
 	struct timer_list mem_timer;
-	struct rvt_qp __rcu **qp_table;
 	struct qib_pio_header *pio_hdrs;
 	dma_addr_t pio_hdrs_phys;
-	/* list of QPs waiting for RNR timer */
-	u32 qp_table_size; /* size of the hash table */
 	u32 qp_rnd; /* random bytes for hash */
-	spinlock_t qpt_lock;
 
 	u32 n_piowait;
 	u32 n_txwait;
@@ -581,9 +552,9 @@ int qib_query_qp(struct ib_qp *ibqp, struct ib_qp_attr *attr,
 
 unsigned qib_free_all_qps(struct qib_devdata *dd);
 
-void qib_init_qpn_table(struct qib_devdata *dd, struct qib_qpn_table *qpt);
+void qib_init_qpn_table(struct qib_devdata *dd, struct rvt_qpn_table *qpt);
 
-void qib_free_qpn_table(struct qib_qpn_table *qpt);
+void qib_free_qpn_table(struct rvt_qpn_table *qpt);
 
 #ifdef CONFIG_DEBUG_FS