Commit 0c0cbfdb authored by Kent Overstreet's avatar Kent Overstreet
Browse files

bcachefs: bch2_dir_emit() - drop_locks_do() conversion 



Add a new helper that calls dir_emit() and updates ctx->pos on success;
this lets us convert bch2_readdir() to drop_locks_do().

Signed-off-by: default avatarKent Overstreet <kent.overstreet@linux.dev>
parent 65bd4423

fs/bcachefs/dirent.c

+26 −20
Original line number Diff line number Diff line
@@ -528,16 +528,26 @@ int bch2_empty_dir_trans(struct btree_trans *trans, subvol_inum dir) 
		bch2_empty_dir_snapshot(trans, dir.inum, dir.subvol, snapshot);

}



static int bch2_dir_emit(struct dir_context *ctx, struct bkey_s_c_dirent d, subvol_inum target)

{

	struct qstr name = bch2_dirent_get_name(d);

	bool ret = dir_emit(ctx, name.name,

		      name.len,

		      target.inum,

		      vfs_d_type(d.v->d_type));

	if (ret)

		ctx->pos = d.k->p.offset + 1;

	return ret;

}



int bch2_readdir(struct bch_fs *c, subvol_inum inum, struct dir_context *ctx)

{

	struct btree_trans *trans = bch2_trans_get(c);

	struct btree_iter iter;

	struct bkey_s_c k;

	struct bkey_s_c_dirent dirent;

	subvol_inum target;

	u32 snapshot;

	struct bkey_buf sk;

	struct qstr name;

	int ret;



	bch2_bkey_buf_init(&sk);
@@ -554,7 +564,9 @@ int bch2_readdir(struct bch_fs *c, subvol_inum inum, struct dir_context *ctx) 
		if (k.k->type != KEY_TYPE_dirent)

			continue;



		dirent = bkey_s_c_to_dirent(k);

		/* dir_emit() can fault and block: */

		bch2_bkey_buf_reassemble(&sk, c, k);

		struct bkey_s_c_dirent dirent = bkey_i_to_s_c_dirent(sk.k);



		ret = bch2_dirent_read_target(trans, inum, dirent, &target);

		if (ret < 0)
@@ -562,29 +574,23 @@ int bch2_readdir(struct bch_fs *c, subvol_inum inum, struct dir_context *ctx) 
		if (ret)

			continue;



		/* dir_emit() can fault and block: */

		bch2_bkey_buf_reassemble(&sk, c, k);

		dirent = bkey_i_to_s_c_dirent(sk.k);

		bch2_trans_unlock(trans);



		name = bch2_dirent_get_name(dirent);



		ctx->pos = dirent.k->p.offset;

		if (!dir_emit(ctx, name.name,

			      name.len,

			      target.inum,

			      vfs_d_type(dirent.v->d_type)))

			break;

		ctx->pos = dirent.k->p.offset + 1;



		/*

		 * read_target looks up subvolumes, we can overflow paths if the

		 * directory has many subvolumes in it

		 *

		 * XXX: btree_trans_too_many_iters() is something we'd like to

		 * get rid of, and there's no good reason to be using it here

		 * except that we don't yet have a for_each_btree_key() helper

		 * that does subvolume_get_snapshot().

		 */

		ret = btree_trans_too_many_iters(trans);

		if (ret)

		ret =   drop_locks_do(trans,

				bch2_dir_emit(ctx, dirent, target)) ?:

			btree_trans_too_many_iters(trans);

		if (ret) {

			ret = ret < 0 ? ret : 0;

			break;

		}

	}

	bch2_trans_iter_exit(trans, &iter);

err:

	if (bch2_err_matches(ret, BCH_ERR_transaction_restart))