RDMA/rxe: Let pools support both keys and indices

Allow both indices and keys to exist for objects in pools.  Previously you
were limited to one or the other.

This is required for later implementing rxe memory windows.

Link: https://lore.kernel.org/r/20201216231550.27224-3-rpearson@hpe.com
Signed-off-by: Bob Pearson <rpearson@hpe.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

2 files changed, 58 insertions, 47 deletions

diff --git a/drivers/infiniband/sw/rxe/rxe_pool.c b/drivers/infiniband/sw/rxe/rxe_pool.c
index 11571ff64a8f..f1ecf5983742 100644
--- a/drivers/infiniband/sw/rxe/rxe_pool.c
+++ b/drivers/infiniband/sw/rxe/rxe_pool.c
@@ -94,18 +94,18 @@ static int rxe_pool_init_index(struct rxe_pool *pool, u32 max, u32 min)
 		goto out;
 	}
 
-	pool->max_index = max;
-	pool->min_index = min;
+	pool->index.max_index = max;
+	pool->index.min_index = min;
 
 	size = BITS_TO_LONGS(max - min + 1) * sizeof(long);
-	pool->table = kmalloc(size, GFP_KERNEL);
-	if (!pool->table) {
+	pool->index.table = kmalloc(size, GFP_KERNEL);
+	if (!pool->index.table) {
 		err = -ENOMEM;
 		goto out;
 	}
 
-	pool->table_size = size;
-	bitmap_zero(pool->table, max - min + 1);
+	pool->index.table_size = size;
+	bitmap_zero(pool->index.table, max - min + 1);
 
 out:
 	return err;
@@ -127,7 +127,8 @@ int rxe_pool_init(
 	pool->max_elem		= max_elem;
 	pool->elem_size		= ALIGN(size, RXE_POOL_ALIGN);
 	pool->flags		= rxe_type_info[type].flags;
-	pool->tree		= RB_ROOT;
+	pool->index.tree	= RB_ROOT;
+	pool->key.tree		= RB_ROOT;
 	pool->cleanup		= rxe_type_info[type].cleanup;
 
 	atomic_set(&pool->num_elem, 0);
@@ -145,8 +146,8 @@ int rxe_pool_init(
 	}
 
 	if (rxe_type_info[type].flags & RXE_POOL_KEY) {
-		pool->key_offset = rxe_type_info[type].key_offset;
-		pool->key_size = rxe_type_info[type].key_size;
+		pool->key.key_offset = rxe_type_info[type].key_offset;
+		pool->key.key_size = rxe_type_info[type].key_size;
 	}
 
 	pool->state = RXE_POOL_STATE_VALID;
@@ -160,7 +161,7 @@ static void rxe_pool_release(struct kref *kref)
 	struct rxe_pool *pool = container_of(kref, struct rxe_pool, ref_cnt);
 
 	pool->state = RXE_POOL_STATE_INVALID;
-	kfree(pool->table);
+	kfree(pool->index.table);
 }
 
 static void rxe_pool_put(struct rxe_pool *pool)
@@ -185,27 +186,27 @@ void rxe_pool_cleanup(struct rxe_pool *pool)
 static u32 alloc_index(struct rxe_pool *pool)
 {
 	u32 index;
-	u32 range = pool->max_index - pool->min_index + 1;
+	u32 range = pool->index.max_index - pool->index.min_index + 1;
 
-	index = find_next_zero_bit(pool->table, range, pool->last);
+	index = find_next_zero_bit(pool->index.table, range, pool->index.last);
 	if (index >= range)
-		index = find_first_zero_bit(pool->table, range);
+		index = find_first_zero_bit(pool->index.table, range);
 
 	WARN_ON_ONCE(index >= range);
-	set_bit(index, pool->table);
-	pool->last = index;
-	return index + pool->min_index;
+	set_bit(index, pool->index.table);
+	pool->index.last = index;
+	return index + pool->index.min_index;
 }
 
 static void insert_index(struct rxe_pool *pool, struct rxe_pool_entry *new)
 {
-	struct rb_node **link = &pool->tree.rb_node;
+	struct rb_node **link = &pool->index.tree.rb_node;
 	struct rb_node *parent = NULL;
 	struct rxe_pool_entry *elem;
 
 	while (*link) {
 		parent = *link;
-		elem = rb_entry(parent, struct rxe_pool_entry, node);
+		elem = rb_entry(parent, struct rxe_pool_entry, index_node);
 
 		if (elem->index == new->index) {
 			pr_warn("element already exists!\n");
@@ -218,25 +219,25 @@ static void insert_index(struct rxe_pool *pool, struct rxe_pool_entry *new)
 			link = &(*link)->rb_right;
 	}
 
-	rb_link_node(&new->node, parent, link);
-	rb_insert_color(&new->node, &pool->tree);
+	rb_link_node(&new->index_node, parent, link);
+	rb_insert_color(&new->index_node, &pool->index.tree);
 out:
 	return;
 }
 
 static void insert_key(struct rxe_pool *pool, struct rxe_pool_entry *new)
 {
-	struct rb_node **link = &pool->tree.rb_node;
+	struct rb_node **link = &pool->key.tree.rb_node;
 	struct rb_node *parent = NULL;
 	struct rxe_pool_entry *elem;
 	int cmp;
 
 	while (*link) {
 		parent = *link;
-		elem = rb_entry(parent, struct rxe_pool_entry, node);
+		elem = rb_entry(parent, struct rxe_pool_entry, key_node);
 
-		cmp = memcmp((u8 *)elem + pool->key_offset,
-			     (u8 *)new + pool->key_offset, pool->key_size);
+		cmp = memcmp((u8 *)elem + pool->key.key_offset,
+			     (u8 *)new + pool->key.key_offset, pool->key.key_size);
 
 		if (cmp == 0) {
 			pr_warn("key already exists!\n");
@@ -249,8 +250,8 @@ static void insert_key(struct rxe_pool *pool, struct rxe_pool_entry *new)
 			link = &(*link)->rb_right;
 	}
 
-	rb_link_node(&new->node, parent, link);
-	rb_insert_color(&new->node, &pool->tree);
+	rb_link_node(&new->key_node, parent, link);
+	rb_insert_color(&new->key_node, &pool->key.tree);
 out:
 	return;
 }
@@ -262,7 +263,7 @@ void rxe_add_key(void *arg, void *key)
 	unsigned long flags;
 
 	write_lock_irqsave(&pool->pool_lock, flags);
-	memcpy((u8 *)elem + pool->key_offset, key, pool->key_size);
+	memcpy((u8 *)elem + pool->key.key_offset, key, pool->key.key_size);
 	insert_key(pool, elem);
 	write_unlock_irqrestore(&pool->pool_lock, flags);
 }
@@ -274,7 +275,7 @@ void rxe_drop_key(void *arg)
 	unsigned long flags;
 
 	write_lock_irqsave(&pool->pool_lock, flags);
-	rb_erase(&elem->node, &pool->tree);
+	rb_erase(&elem->key_node, &pool->key.tree);
 	write_unlock_irqrestore(&pool->pool_lock, flags);
 }
 
@@ -297,8 +298,8 @@ void rxe_drop_index(void *arg)
 	unsigned long flags;
 
 	write_lock_irqsave(&pool->pool_lock, flags);
-	clear_bit(elem->index - pool->min_index, pool->table);
-	rb_erase(&elem->node, &pool->tree);
+	clear_bit(elem->index - pool->index.min_index, pool->index.table);
+	rb_erase(&elem->index_node, &pool->index.tree);
 	write_unlock_irqrestore(&pool->pool_lock, flags);
 }
 
@@ -402,10 +403,10 @@ void *rxe_pool_get_index(struct rxe_pool *pool, u32 index)
 	if (pool->state != RXE_POOL_STATE_VALID)
 		goto out;
 
-	node = pool->tree.rb_node;
+	node = pool->index.tree.rb_node;
 
 	while (node) {
-		elem = rb_entry(node, struct rxe_pool_entry, node);
+		elem = rb_entry(node, struct rxe_pool_entry, index_node);
 
 		if (elem->index > index)
 			node = node->rb_left;
@@ -434,13 +435,13 @@ void *rxe_pool_get_key(struct rxe_pool *pool, void *key)
 	if (pool->state != RXE_POOL_STATE_VALID)
 		goto out;
 
-	node = pool->tree.rb_node;
+	node = pool->key.tree.rb_node;
 
 	while (node) {
-		elem = rb_entry(node, struct rxe_pool_entry, node);
+		elem = rb_entry(node, struct rxe_pool_entry, key_node);
 
-		cmp = memcmp((u8 *)elem + pool->key_offset,
-			     key, pool->key_size);
+		cmp = memcmp((u8 *)elem + pool->key.key_offset,
+			     key, pool->key.key_size);
 
 		if (cmp > 0)
 			node = node->rb_left;
diff --git a/drivers/infiniband/sw/rxe/rxe_pool.h b/drivers/infiniband/sw/rxe/rxe_pool.h
index 432745ffc8d4..3d722aae5f15 100644
--- a/drivers/infiniband/sw/rxe/rxe_pool.h
+++ b/drivers/infiniband/sw/rxe/rxe_pool.h
@@ -56,8 +56,11 @@ struct rxe_pool_entry {
 	struct kref		ref_cnt;
 	struct list_head	list;
 
-	/* only used if indexed or keyed */
-	struct rb_node		node;
+	/* only used if keyed */
+	struct rb_node		key_node;
+
+	/* only used if indexed */
+	struct rb_node		index_node;
 	u32			index;
 };
 
@@ -74,15 +77,22 @@ struct rxe_pool {
 	unsigned int		max_elem;
 	atomic_t		num_elem;
 
-	/* only used if indexed or keyed */
-	struct rb_root		tree;
-	unsigned long		*table;
-	size_t			table_size;
-	u32			max_index;
-	u32			min_index;
-	u32			last;
-	size_t			key_offset;
-	size_t			key_size;
+	/* only used if indexed */
+	struct {
+		struct rb_root		tree;
+		unsigned long		*table;
+		size_t			table_size;
+		u32			last;
+		u32			max_index;
+		u32			min_index;
+	} index;
+
+	/* only used if keyed */
+	struct {
+		struct rb_root		tree;
+		size_t			key_offset;
+		size_t			key_size;
+	} key;
 };
 
 /* initialize a pool of objects with given limit on