Commit 3c5d0b72 authored by Kent Overstreet's avatar Kent Overstreet
Browse files

bcachefs: fix failure to relock in bch2_btree_node_mem_alloc() 



We weren't always so strict about trans->locked state - but now we are,
and new assertions are shaking some bugs out.

Signed-off-by: default avatarKent Overstreet <kent.overstreet@linux.dev>
parent 1dceae4c

fs/bcachefs/btree_cache.c

+17 −0
Original line number Diff line number Diff line
@@ -159,6 +159,16 @@ struct btree *__bch2_btree_node_mem_alloc(struct bch_fs *c) 
	return b;

}



void bch2_btree_node_to_freelist(struct bch_fs *c, struct btree *b)

{

	mutex_lock(&c->btree_cache.lock);

	list_move(&b->list, &c->btree_cache.freeable);

	mutex_unlock(&c->btree_cache.lock);



	six_unlock_write(&b->c.lock);

	six_unlock_intent(&b->c.lock);

}



/* Btree in memory cache - hash table */



void bch2_btree_node_hash_remove(struct btree_cache *bc, struct btree *b)
@@ -736,6 +746,13 @@ struct btree *bch2_btree_node_mem_alloc(struct btree_trans *trans, bool pcpu_rea 
			       start_time);



	memalloc_nofs_restore(flags);



	int ret = bch2_trans_relock(trans);

	if (unlikely(ret)) {

		bch2_btree_node_to_freelist(c, b);

		return ERR_PTR(ret);

	}



	return b;

err:

	mutex_lock(&bc->lock);

fs/bcachefs/btree_cache.h

+2 −0
Original line number Diff line number Diff line
@@ -12,6 +12,8 @@ struct btree_iter; 


void bch2_recalc_btree_reserve(struct bch_fs *);



void bch2_btree_node_to_freelist(struct bch_fs *, struct btree *);



void bch2_btree_node_hash_remove(struct btree_cache *, struct btree *);

int __bch2_btree_node_hash_insert(struct btree_cache *, struct btree *);

int bch2_btree_node_hash_insert(struct btree_cache *, struct btree *,

fs/bcachefs/btree_update_interior.c

+25 −21
Original line number Diff line number Diff line
@@ -317,6 +317,12 @@ static struct btree *__bch2_btree_node_alloc(struct btree_trans *trans, 
		: 0;

	int ret;



	b = bch2_btree_node_mem_alloc(trans, interior_node);

	if (IS_ERR(b))

		return b;



	BUG_ON(b->ob.nr);



	mutex_lock(&c->btree_reserve_cache_lock);

	if (c->btree_reserve_cache_nr > nr_reserve) {

		struct btree_alloc *a =
@@ -325,10 +331,9 @@ static struct btree *__bch2_btree_node_alloc(struct btree_trans *trans, 
		obs = a->ob;

		bkey_copy(&tmp.k, &a->k);

		mutex_unlock(&c->btree_reserve_cache_lock);

		goto mem_alloc;

		goto out;

	}

	mutex_unlock(&c->btree_reserve_cache_lock);



retry:

	ret = bch2_alloc_sectors_start_trans(trans,

				      c->opts.metadata_target ?:
@@ -341,7 +346,7 @@ static struct btree *__bch2_btree_node_alloc(struct btree_trans *trans, 
					  c->opts.metadata_replicas_required),

				      watermark, 0, cl, &wp);

	if (unlikely(ret))

		return ERR_PTR(ret);

		goto err;



	if (wp->sectors_free < btree_sectors(c)) {

		struct open_bucket *ob;
@@ -360,19 +365,16 @@ static struct btree *__bch2_btree_node_alloc(struct btree_trans *trans, 


	bch2_open_bucket_get(c, wp, &obs);

	bch2_alloc_sectors_done(c, wp);

mem_alloc:

	b = bch2_btree_node_mem_alloc(trans, interior_node);

	six_unlock_write(&b->c.lock);

	six_unlock_intent(&b->c.lock);



	/* we hold cannibalize_lock: */

	BUG_ON(IS_ERR(b));

	BUG_ON(b->ob.nr);



out:

	bkey_copy(&b->key, &tmp.k);

	b->ob = obs;

	six_unlock_write(&b->c.lock);

	six_unlock_intent(&b->c.lock);



	return b;

err:

	bch2_btree_node_to_freelist(c, b);

	return ERR_PTR(ret);

}



static struct btree *bch2_btree_node_alloc(struct btree_update *as,
@@ -2439,6 +2441,9 @@ int bch2_btree_node_update_key(struct btree_trans *trans, struct btree_iter *ite 
		}



		new_hash = bch2_btree_node_mem_alloc(trans, false);

		ret = PTR_ERR_OR_ZERO(new_hash);

		if (ret)

			goto err;

	}



	path->intent_ref++;
@@ -2446,14 +2451,9 @@ int bch2_btree_node_update_key(struct btree_trans *trans, struct btree_iter *ite 
					   commit_flags, skip_triggers);

	--path->intent_ref;



	if (new_hash) {

		mutex_lock(&c->btree_cache.lock);

		list_move(&new_hash->list, &c->btree_cache.freeable);

		mutex_unlock(&c->btree_cache.lock);



		six_unlock_write(&new_hash->c.lock);

		six_unlock_intent(&new_hash->c.lock);

	}

	if (new_hash)

		bch2_btree_node_to_freelist(c, new_hash);

err:

	closure_sync(&cl);

	bch2_btree_cache_cannibalize_unlock(trans);

	return ret;
@@ -2522,6 +2522,10 @@ int bch2_btree_root_alloc_fake_trans(struct btree_trans *trans, enum btree_id id 
	b = bch2_btree_node_mem_alloc(trans, false);

	bch2_btree_cache_cannibalize_unlock(trans);



	ret = PTR_ERR_OR_ZERO(b);

	if (ret)

		return ret;



	set_btree_node_fake(b);

	set_btree_node_need_rewrite(b);

	b->c.level	= level;
@@ -2553,7 +2557,7 @@ int bch2_btree_root_alloc_fake_trans(struct btree_trans *trans, enum btree_id id 


void bch2_btree_root_alloc_fake(struct bch_fs *c, enum btree_id id, unsigned level)

{

	bch2_trans_run(c, bch2_btree_root_alloc_fake_trans(trans, id, level));

	bch2_trans_run(c, lockrestart_do(trans, bch2_btree_root_alloc_fake_trans(trans, id, level)));

}



static void bch2_btree_update_to_text(struct printbuf *out, struct btree_update *as)