libceph: add non-asserting rbtree insertion helper

Needed for the next commit and useful for ceph_pg_pool_info tree as
well.  I'm leaving the asserting helper in for now, but we should look
at getting rid of it in the future.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>

include/linux/ceph/libceph.h

@@ -188,7 +188,7 @@ static inline int calc_pages_for(u64 off, u64 len)
 #define RB_CMP3WAY(a, b) ((a) < (b) ? -1 : (a) > (b))
 
 #define DEFINE_RB_INSDEL_FUNCS2(name, type, keyfld, cmpexp, keyexp, nodefld) \
-static void insert_##name(struct rb_root *root, type *t)		\
+static bool __insert_##name(struct rb_root *root, type *t)		\
 {									\
 	struct rb_node **n = &root->rb_node;				\
 	struct rb_node *parent = NULL;					\
@@ -206,11 +206,17 @@ static void insert_##name(struct rb_root *root, type *t)		\
 		else if (cmp > 0)					\
 			n = &(*n)->rb_right;				\
 		else							\
-			BUG();						\
+			return false;					\
 	}								\
 									\
 	rb_link_node(&t->nodefld, parent, n);				\
 	rb_insert_color(&t->nodefld, root);				\
+	return true;							\
+}									\
+static void __maybe_unused insert_##name(struct rb_root *root, type *t)	\
+{									\
+	if (!__insert_##name(root, t))					\
+		BUG();							\
 }									\
 static void erase_##name(struct rb_root *root, type *t)			\
 {									\

net/ceph/osdmap.c

@@ -636,48 +636,11 @@ DEFINE_RB_FUNCS2(pg_mapping, struct ceph_pg_mapping, pgid, ceph_pg_compare,
 /*
  * rbtree of pg pool info
  */
-static int __insert_pg_pool(struct rb_root *root, struct ceph_pg_pool_info *new)
-{
-	struct rb_node **p = &root->rb_node;
-	struct rb_node *parent = NULL;
-	struct ceph_pg_pool_info *pi = NULL;
-
-	while (*p) {
-		parent = *p;
-		pi = rb_entry(parent, struct ceph_pg_pool_info, node);
-		if (new->id < pi->id)
-			p = &(*p)->rb_left;
-		else if (new->id > pi->id)
-			p = &(*p)->rb_right;
-		else
-			return -EEXIST;
-	}
-
-	rb_link_node(&new->node, parent, p);
-	rb_insert_color(&new->node, root);
-	return 0;
-}
-
-static struct ceph_pg_pool_info *__lookup_pg_pool(struct rb_root *root, u64 id)
-{
-	struct ceph_pg_pool_info *pi;
-	struct rb_node *n = root->rb_node;
-
-	while (n) {
-		pi = rb_entry(n, struct ceph_pg_pool_info, node);
-		if (id < pi->id)
-			n = n->rb_left;
-		else if (id > pi->id)
-			n = n->rb_right;
-		else
-			return pi;
-	}
-	return NULL;
-}
+DEFINE_RB_FUNCS(pg_pool, struct ceph_pg_pool_info, id, node)
 
 struct ceph_pg_pool_info *ceph_pg_pool_by_id(struct ceph_osdmap *map, u64 id)
 {
-	return __lookup_pg_pool(&map->pg_pools, id);
+	return lookup_pg_pool(&map->pg_pools, id);
 }
 
 const char *ceph_pg_pool_name_by_id(struct ceph_osdmap *map, u64 id)
@@ -690,8 +653,7 @@ const char *ceph_pg_pool_name_by_id(struct ceph_osdmap *map, u64 id)
 	if (WARN_ON_ONCE(id > (u64) INT_MAX))
 		return NULL;
 
-	pi = __lookup_pg_pool(&map->pg_pools, (int) id);
-
+	pi = lookup_pg_pool(&map->pg_pools, id);
 	return pi ? pi->name : NULL;
 }
 EXPORT_SYMBOL(ceph_pg_pool_name_by_id);
@@ -714,14 +676,14 @@ u64 ceph_pg_pool_flags(struct ceph_osdmap *map, u64 id)
 {
 	struct ceph_pg_pool_info *pi;
 
-	pi = __lookup_pg_pool(&map->pg_pools, id);
+	pi = lookup_pg_pool(&map->pg_pools, id);
 	return pi ? pi->flags : 0;
 }
 EXPORT_SYMBOL(ceph_pg_pool_flags);
 
 static void __remove_pg_pool(struct rb_root *root, struct ceph_pg_pool_info *pi)
 {
-	rb_erase(&pi->node, root);
+	erase_pg_pool(root, pi);
 	kfree(pi->name);
 	kfree(pi);
 }
@@ -903,7 +865,7 @@ static int decode_pool_names(void **p, void *end, struct ceph_osdmap *map)
 		ceph_decode_32_safe(p, end, len, bad);
 		dout("  pool %llu len %d\n", pool, len);
 		ceph_decode_need(p, end, len, bad);
-		pi = __lookup_pg_pool(&map->pg_pools, pool);
+		pi = lookup_pg_pool(&map->pg_pools, pool);
 		if (pi) {
 			char *name = kstrndup(*p, len, GFP_NOFS);
 
@@ -1154,18 +1116,18 @@ static int __decode_pools(void **p, void *end, struct ceph_osdmap *map,
 
 		ceph_decode_64_safe(p, end, pool, e_inval);
 
-		pi = __lookup_pg_pool(&map->pg_pools, pool);
+		pi = lookup_pg_pool(&map->pg_pools, pool);
 		if (!incremental || !pi) {
 			pi = kzalloc(sizeof(*pi), GFP_NOFS);
 			if (!pi)
 				return -ENOMEM;
 
+			RB_CLEAR_NODE(&pi->node);
 			pi->id = pool;
 
-			ret = __insert_pg_pool(&map->pg_pools, pi);
-			if (ret) {
+			if (!__insert_pg_pool(&map->pg_pools, pi)) {
 				kfree(pi);
-				return ret;
+				return -EEXIST;
 			}
 		}
 
@@ -1829,7 +1791,7 @@ struct ceph_osdmap *osdmap_apply_incremental(void **p, void *end,
 		struct ceph_pg_pool_info *pi;
 
 		ceph_decode_64_safe(p, end, pool, e_inval);
-		pi = __lookup_pg_pool(&map->pg_pools, pool);
+		pi = lookup_pg_pool(&map->pg_pools, pool);
 		if (pi)
 			__remove_pg_pool(&map->pg_pools, pi);
 	}