bcachefs: darray_find(), darray_find_p()

New helpers to avoid open coded loops.

Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

Author: Kent Overstreet

fs/bcachefs/alloc_background.c

@@ -1792,11 +1792,12 @@ static int discard_in_flight_add(struct bch_dev *ca, u64 bucket, bool in_progres
 	int ret;
 
 	mutex_lock(&ca->discard_buckets_in_flight_lock);
-	darray_for_each(ca->discard_buckets_in_flight, i)
-		if (i->bucket == bucket) {
-			ret = -BCH_ERR_EEXIST_discard_in_flight_add;
-			goto out;
-		}
+	struct discard_in_flight *i =
+		darray_find_p(ca->discard_buckets_in_flight, i, i->bucket == bucket);
+	if (i) {
+		ret = -BCH_ERR_EEXIST_discard_in_flight_add;
+		goto out;
+	}
 
 	ret = darray_push(&ca->discard_buckets_in_flight, ((struct discard_in_flight) {
 			   .in_progress = in_progress,
@@ -1810,14 +1811,11 @@ static int discard_in_flight_add(struct bch_dev *ca, u64 bucket, bool in_progres
 static void discard_in_flight_remove(struct bch_dev *ca, u64 bucket)
 {
 	mutex_lock(&ca->discard_buckets_in_flight_lock);
-	darray_for_each(ca->discard_buckets_in_flight, i)
-		if (i->bucket == bucket) {
-			BUG_ON(!i->in_progress);
-			darray_remove_item(&ca->discard_buckets_in_flight, i);
-			goto found;
-		}
-	BUG();
-found:
+	struct discard_in_flight *i =
+		darray_find_p(ca->discard_buckets_in_flight, i, i->bucket == bucket);
+	BUG_ON(!i || !i->in_progress);
+
+	darray_remove_item(&ca->discard_buckets_in_flight, i);
 	mutex_unlock(&ca->discard_buckets_in_flight_lock);
 }
 

fs/bcachefs/darray.h

@@ -87,7 +87,23 @@ int __bch2_darray_resize_noprof(darray_char *, size_t, size_t, gfp_t);
 #define darray_remove_item(_d, _pos)					\
 	array_remove_item((_d)->data, (_d)->nr, (_pos) - (_d)->data)
 
-#define __darray_for_each(_d, _i)						\
+#define darray_find_p(_d, _i, cond)					\
+({									\
+	typeof((_d).data) _ret = NULL;					\
+									\
+	darray_for_each(_d, _i)						\
+		if (cond) {						\
+			_ret = _i;					\
+			break;						\
+		}							\
+	_ret;								\
+})
+
+#define darray_find(_d, _item)	darray_find_p(_d, _i, *_i == _item)
+
+/* Iteration: */
+
+#define __darray_for_each(_d, _i)					\
 	for ((_i) = (_d).data; _i < (_d).data + (_d).nr; _i++)
 
 #define darray_for_each(_d, _i)						\

fs/bcachefs/fsck.c

@@ -885,14 +885,11 @@ lookup_inode_for_snapshot(struct btree_trans *trans, struct inode_walker *w, str
 {
 	struct bch_fs *c = trans->c;
 
-	struct inode_walker_entry *i;
-	__darray_for_each(w->inodes, i)
-		if (bch2_snapshot_is_ancestor(c, k.k->p.snapshot, i->inode.bi_snapshot))
-			goto found;
+	struct inode_walker_entry *i = darray_find_p(w->inodes, i,
+		    bch2_snapshot_is_ancestor(c, k.k->p.snapshot, i->inode.bi_snapshot));
 
-	return NULL;
-found:
-	BUG_ON(k.k->p.snapshot > i->inode.bi_snapshot);
+	if (!i)
+		return NULL;
 
 	struct printbuf buf = PRINTBUF;
 	int ret = 0;

fs/bcachefs/snapshot.c

@@ -947,10 +947,7 @@ static inline bool same_snapshot(struct snapshot_tree_reconstruct *r, struct bpo
 
 static inline bool snapshot_id_lists_have_common(snapshot_id_list *l, snapshot_id_list *r)
 {
-	darray_for_each(*l, i)
-		if (snapshot_list_has_id(r, *i))
-			return true;
-	return false;
+	return darray_find_p(*l, i, snapshot_list_has_id(r, *i)) != NULL;
 }
 
 static void snapshot_id_list_to_text(struct printbuf *out, snapshot_id_list *s)
@@ -1428,10 +1425,8 @@ int bch2_snapshot_node_create(struct btree_trans *trans, u32 parent,
 
 static inline u32 interior_delete_has_id(interior_delete_list *l, u32 id)
 {
-	darray_for_each(*l, i)
-		if (i->id == id)
-			return i->live_child;
-	return 0;
+	struct snapshot_interior_delete *i = darray_find_p(*l, i, i->id == id);
+	return i ? i->live_child : 0;
 }
 
 static unsigned __live_child(struct snapshot_table *t, u32 id,

fs/bcachefs/snapshot.h

@@ -190,10 +190,7 @@ static inline bool bch2_snapshot_has_children(struct bch_fs *c, u32 id)
 
 static inline bool snapshot_list_has_id(snapshot_id_list *s, u32 id)
 {
-	darray_for_each(*s, i)
-		if (*i == id)
-			return true;
-	return false;
+	return darray_find(*s, id) != NULL;
 }
 
 static inline bool snapshot_list_has_ancestor(struct bch_fs *c, snapshot_id_list *s, u32 id)