Commit 9c4acd19 authored by Kent Overstreet's avatar Kent Overstreet
Browse files

bcachefs: Replace bucket_valid() asserts in bucket lookup with proper checks 



The bucket_gens array and gc_buckets array known their own size; we
should be using those members, and returning an error.

Signed-off-by: default avatarKent Overstreet <kent.overstreet@linux.dev>
parent e0cb5722

fs/bcachefs/btree_gc.c

+2 −0
Original line number Diff line number Diff line
@@ -990,6 +990,8 @@ static int bch2_gc_alloc_start(struct bch_fs *c) 


		buckets->first_bucket	= ca->mi.first_bucket;

		buckets->nbuckets	= ca->mi.nbuckets;

		buckets->nbuckets_minus_first =

			buckets->nbuckets - buckets->first_bucket;

		rcu_assign_pointer(ca->buckets_gc, buckets);

	}

fs/bcachefs/buckets.c

+2 −0
Original line number Diff line number Diff line
@@ -1612,6 +1612,8 @@ int bch2_dev_buckets_resize(struct bch_fs *c, struct bch_dev *ca, u64 nbuckets) 


	bucket_gens->first_bucket = ca->mi.first_bucket;

	bucket_gens->nbuckets	= nbuckets;

	bucket_gens->nbuckets_minus_first =

		bucket_gens->nbuckets - bucket_gens->first_bucket;



	if (resize) {

		down_write(&c->gc_lock);

fs/bcachefs/buckets.h

+4 −2
Original line number Diff line number Diff line
@@ -93,7 +93,8 @@ static inline struct bucket *gc_bucket(struct bch_dev *ca, size_t b) 
{

	struct bucket_array *buckets = gc_bucket_array(ca);



	BUG_ON(!bucket_valid(ca, b));

	if (b - buckets->first_bucket >= buckets->nbuckets_minus_first)

		return NULL;

	return buckets->b + b;

}
@@ -110,7 +111,8 @@ static inline u8 *bucket_gen(struct bch_dev *ca, size_t b) 
{

	struct bucket_gens *gens = bucket_gens(ca);



	BUG_ON(!bucket_valid(ca, b));

	if (b - gens->first_bucket >= gens->nbuckets_minus_first)

		return NULL;

	return gens->b + b;

}

fs/bcachefs/buckets_types.h

+2 −0
Original line number Diff line number Diff line
@@ -22,6 +22,7 @@ struct bucket_array { 
	struct rcu_head		rcu;

	u16			first_bucket;

	size_t			nbuckets;

	size_t			nbuckets_minus_first;

	struct bucket		b[];

};
@@ -29,6 +30,7 @@ struct bucket_gens { 
	struct rcu_head		rcu;

	u16			first_bucket;

	size_t			nbuckets;

	size_t			nbuckets_minus_first;

	u8			b[];

};