Commit dc96656b authored by Kent Overstreet's avatar Kent Overstreet
Browse files

bcachefs: bch2_hash_set_or_get_in_snapshot() 



Add a variant of bch2_hash_set_in_snapshot() that returns the existing
key on -EEXIST.

Signed-off-by: default avatarKent Overstreet <kent.overstreet@linux.dev>
parent 15a3836c

fs/bcachefs/str_hash.h

+36 −14
Original line number Diff line number Diff line
@@ -252,19 +252,20 @@ int bch2_hash_needs_whiteout(struct btree_trans *trans, 
}



static __always_inline

int bch2_hash_set_in_snapshot(struct btree_trans *trans,

struct bkey_s_c bch2_hash_set_or_get_in_snapshot(struct btree_trans *trans,

			   struct btree_iter *iter,

			   const struct bch_hash_desc desc,

			   const struct bch_hash_info *info,

			   subvol_inum inum, u32 snapshot,

			   struct bkey_i *insert,

			   enum btree_iter_update_trigger_flags flags)

{

	struct btree_iter iter, slot = { NULL };

	struct btree_iter slot = {};

	struct bkey_s_c k;

	bool found = false;

	int ret;



	for_each_btree_key_upto_norestart(trans, iter, desc.btree_id,

	for_each_btree_key_upto_norestart(trans, *iter, desc.btree_id,

			   SPOS(insert->k.p.inode,

				desc.hash_bkey(info, bkey_i_to_s_c(insert)),

				snapshot),
@@ -279,7 +280,7 @@ int bch2_hash_set_in_snapshot(struct btree_trans *trans, 
		}



		if (!slot.path && !(flags & STR_HASH_must_replace))

			bch2_trans_copy_iter(&slot, &iter);

			bch2_trans_copy_iter(&slot, iter);



		if (k.k->type != KEY_TYPE_hash_whiteout)

			goto not_found;
@@ -289,28 +290,49 @@ int bch2_hash_set_in_snapshot(struct btree_trans *trans, 
		ret = -BCH_ERR_ENOSPC_str_hash_create;

out:

	bch2_trans_iter_exit(trans, &slot);

	bch2_trans_iter_exit(trans, &iter);



	return ret;

	bch2_trans_iter_exit(trans, iter);

	return ret ? bkey_s_c_err(ret) : bkey_s_c_null;

found:

	found = true;

not_found:



	if (!found && (flags & STR_HASH_must_replace)) {

	if (found && (flags & STR_HASH_must_create)) {

		bch2_trans_iter_exit(trans, &slot);

		return k;

	} else if (!found && (flags & STR_HASH_must_replace)) {

		ret = -BCH_ERR_ENOENT_str_hash_set_must_replace;

	} else if (found && (flags & STR_HASH_must_create)) {

		ret = -BCH_ERR_EEXIST_str_hash_set;

	} else {

		if (!found && slot.path)

			swap(iter, slot);

			swap(*iter, slot);



		insert->k.p = iter.pos;

		ret = bch2_trans_update(trans, &iter, insert, flags);

		insert->k.p = iter->pos;

		ret = bch2_trans_update(trans, iter, insert, flags);

	}



	goto out;

}



static __always_inline

int bch2_hash_set_in_snapshot(struct btree_trans *trans,

			   const struct bch_hash_desc desc,

			   const struct bch_hash_info *info,

			   subvol_inum inum, u32 snapshot,

			   struct bkey_i *insert,

			   enum btree_iter_update_trigger_flags flags)

{

	struct btree_iter iter;

	struct bkey_s_c k = bch2_hash_set_or_get_in_snapshot(trans, &iter, desc, info, inum,

							     snapshot, insert, flags);

	int ret = bkey_err(k);

	if (ret)

		return ret;

	if (k.k) {

		bch2_trans_iter_exit(trans, &iter);

		return -BCH_ERR_EEXIST_str_hash_set;

	}



	return 0;

}



static __always_inline

int bch2_hash_set(struct btree_trans *trans,

		  const struct bch_hash_desc desc,