bcachefs: Can't be holding read locks while taking write locks

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

fs/bcachefs/btree_update_leaf.c

@@ -451,6 +451,7 @@ static inline int do_btree_insert_at(struct btree_trans *trans,
 	struct bch_fs *c = trans->c;
 	struct bch_fs_usage_online *fs_usage = NULL;
 	struct btree_insert_entry *i;
+	struct btree_iter *iter;
 	unsigned mark_flags = trans->flags & BTREE_INSERT_BUCKET_INVALIDATE
 		? BCH_BUCKET_MARK_BUCKET_INVALIDATE
 		: 0;
@@ -473,6 +474,14 @@ static inline int do_btree_insert_at(struct btree_trans *trans,
 				goto out_clear_replicas;
 		}
 
+	trans_for_each_iter(trans, iter) {
+		if (iter->nodes_locked != iter->nodes_intent_locked) {
+			BUG_ON(iter->flags & BTREE_ITER_KEEP_UNTIL_COMMIT);
+			BUG_ON(trans->iters_live & (1ULL << iter->idx));
+			__bch2_btree_iter_unlock(iter);
+		}
+	}
+
 	if (IS_ENABLED(CONFIG_BCACHEFS_DEBUG))
 		trans_for_each_update(trans, i)
 			btree_insert_entry_checks(trans, i);

fs/bcachefs/dirent.c

@@ -296,10 +296,10 @@ int bch2_dirent_delete(struct bch_fs *c, u64 dir_inum,
 struct btree_iter *
 __bch2_dirent_lookup_trans(struct btree_trans *trans, u64 dir_inum,
 			   const struct bch_hash_info *hash_info,
-			   const struct qstr *name)
+			   const struct qstr *name, unsigned flags)
 {
 	return bch2_hash_lookup(trans, bch2_dirent_hash_desc,
-				hash_info, dir_inum, name, 0);
+				hash_info, dir_inum, name, flags);
 }
 
 u64 bch2_dirent_lookup(struct bch_fs *c, u64 dir_inum,
@@ -313,7 +313,8 @@ u64 bch2_dirent_lookup(struct bch_fs *c, u64 dir_inum,
 
 	bch2_trans_init(&trans, c, 0, 0);
 
-	iter = __bch2_dirent_lookup_trans(&trans, dir_inum, hash_info, name);
+	iter = __bch2_dirent_lookup_trans(&trans, dir_inum,
+					  hash_info, name, 0);
 	if (IS_ERR(iter)) {
 		BUG_ON(PTR_ERR(iter) == -EINTR);
 		goto out;

fs/bcachefs/dirent.h

@@ -55,7 +55,7 @@ int bch2_dirent_rename(struct btree_trans *,
 struct btree_iter *
 __bch2_dirent_lookup_trans(struct btree_trans *, u64,
 			   const struct bch_hash_info *,
-			   const struct qstr *);
+			   const struct qstr *, unsigned);
 u64 bch2_dirent_lookup(struct bch_fs *, u64, const struct bch_hash_info *,
 		       const struct qstr *);
 

fs/bcachefs/fs-common.c

@@ -24,8 +24,7 @@ int bch2_create_trans(struct btree_trans *trans, u64 dir_inum,
 	u64 now = bch2_current_time(trans->c);
 	int ret;
 
-	dir_iter = bch2_inode_peek(trans, dir_u, dir_inum,
-				   name ? BTREE_ITER_INTENT : 0);
+	dir_iter = bch2_inode_peek(trans, dir_u, dir_inum, BTREE_ITER_INTENT);
 	if (IS_ERR(dir_iter))
 		return PTR_ERR(dir_iter);
 
@@ -76,8 +75,7 @@ int bch2_create_trans(struct btree_trans *trans, u64 dir_inum,
 	return 0;
 }
 
-int bch2_link_trans(struct btree_trans *trans,
-		    u64 dir_inum,
+int bch2_link_trans(struct btree_trans *trans, u64 dir_inum,
 		    u64 inum, struct bch_inode_unpacked *inode_u,
 		    const struct qstr *name)
 {
@@ -86,19 +84,22 @@ int bch2_link_trans(struct btree_trans *trans,
 	struct bch_hash_info dir_hash;
 	u64 now = bch2_current_time(trans->c);
 
-	dir_iter = bch2_inode_peek(trans, &dir_u, dir_inum, 0);
-	if (IS_ERR(dir_iter))
-		return PTR_ERR(dir_iter);
-
 	inode_iter = bch2_inode_peek(trans, inode_u, inum, BTREE_ITER_INTENT);
 	if (IS_ERR(inode_iter))
 		return PTR_ERR(inode_iter);
 
-	dir_hash = bch2_hash_info_init(trans->c, &dir_u);
-
 	inode_u->bi_ctime = now;
 	bch2_inode_nlink_inc(inode_u);
 
+	dir_iter = bch2_inode_peek(trans, &dir_u, dir_inum, 0);
+	if (IS_ERR(dir_iter))
+		return PTR_ERR(dir_iter);
+
+	/* XXX: shouldn't we be updating mtime/ctime on the directory? */
+
+	dir_hash = bch2_hash_info_init(trans->c, &dir_u);
+	bch2_trans_iter_put(trans, dir_iter);
+
 	return bch2_dirent_create(trans, dir_inum, &dir_hash,
 				  mode_to_type(inode_u->bi_mode),
 				  name, inum, BCH_HASH_SET_MUST_CREATE) ?:
@@ -121,8 +122,8 @@ int bch2_unlink_trans(struct btree_trans *trans,
 
 	dir_hash = bch2_hash_info_init(trans->c, dir_u);
 
-	dirent_iter = __bch2_dirent_lookup_trans(trans, dir_inum,
-						 &dir_hash, name);
+	dirent_iter = __bch2_dirent_lookup_trans(trans, dir_inum, &dir_hash,
+						 name, BTREE_ITER_INTENT);
 	if (IS_ERR(dirent_iter))
 		return PTR_ERR(dirent_iter);
 

fs/bcachefs/fs-common.h

@@ -12,8 +12,7 @@ int bch2_create_trans(struct btree_trans *, u64,
 		      struct posix_acl *,
 		      struct posix_acl *);
 
-int bch2_link_trans(struct btree_trans *,
-		    u64,
+int bch2_link_trans(struct btree_trans *, u64,
 		    u64, struct bch_inode_unpacked *,
 		    const struct qstr *);
 

fs/bcachefs/reflink.c

@@ -144,20 +144,18 @@ static int bch2_make_extent_indirect(struct btree_trans *trans,
 static struct bkey_s_c get_next_src(struct btree_iter *iter, struct bpos end)
 {
 	struct bkey_s_c k = bch2_btree_iter_peek(iter);
+	int ret;
 
-	while (1) {
-		if (bkey_err(k))
-			return k;
-
+	for_each_btree_key_continue(iter, 0, k, ret) {
 		if (bkey_cmp(iter->pos, end) >= 0)
 			return bkey_s_c_null;
 
 		if (k.k->type == KEY_TYPE_extent ||
 		    k.k->type == KEY_TYPE_reflink_p)
-			return k;
-
-		k = bch2_btree_iter_next(iter);
+			break;
 	}
+
+	return k;
 }
 
 s64 bch2_remap_range(struct bch_fs *c,