Commit 2c6a7bff authored by Kent Overstreet's avatar Kent Overstreet
Browse files

bcachefs: Switch gc bucket array to a genradix 



A user with a 30 tb device is overflowing the INT_MAX limit on vmalloc
allocations...

Signed-off-by: default avatarKent Overstreet <kent.overstreet@linux.dev>
parent a803fa55

fs/bcachefs/bcachefs.h

+1 −1
Original line number Diff line number Diff line
@@ -542,7 +542,7 @@ struct bch_dev { 
	 * gc_gens_lock, for device resize - holding any is sufficient for

	 * access: Or rcu_read_lock(), but only for dev_ptr_stale():

	 */

	struct bucket_array __rcu *buckets_gc;

	GENRADIX(struct bucket)	buckets_gc;

	struct bucket_gens __rcu *bucket_gens;

	u8			*oldest_gen;

	unsigned long		*buckets_nouse;

fs/bcachefs/btree_gc.c

+4 −14
Original line number Diff line number Diff line
@@ -753,10 +753,8 @@ static void bch2_gc_free(struct bch_fs *c) 
	genradix_free(&c->reflink_gc_table);

	genradix_free(&c->gc_stripes);



	for_each_member_device(c, ca) {

		kvfree(rcu_dereference_protected(ca->buckets_gc, 1));

		ca->buckets_gc = NULL;

	}

	for_each_member_device(c, ca)

		genradix_free(&ca->buckets_gc);

}



static int bch2_gc_start(struct bch_fs *c)
@@ -910,20 +908,12 @@ static int bch2_gc_alloc_start(struct bch_fs *c) 
	int ret = 0;



	for_each_member_device(c, ca) {

		struct bucket_array *buckets = kvmalloc(sizeof(struct bucket_array) +

				ca->mi.nbuckets * sizeof(struct bucket),

				GFP_KERNEL|__GFP_ZERO);

		if (!buckets) {

		ret = genradix_prealloc(&ca->buckets_gc, ca->mi.nbuckets, GFP_KERNEL);

		if (ret) {

			bch2_dev_put(ca);

			ret = -BCH_ERR_ENOMEM_gc_alloc_start;

			break;

		}



		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);

	}



	bch_err_fn(c, ret);

fs/bcachefs/buckets.h

+1 −14
Original line number Diff line number Diff line
@@ -80,22 +80,9 @@ static inline void bucket_lock(struct bucket *b) 
			 TASK_UNINTERRUPTIBLE);

}



static inline struct bucket_array *gc_bucket_array(struct bch_dev *ca)

{

	return rcu_dereference_check(ca->buckets_gc,

				     !ca->fs ||

				     percpu_rwsem_is_held(&ca->fs->mark_lock) ||

				     lockdep_is_held(&ca->fs->state_lock) ||

				     lockdep_is_held(&ca->bucket_lock));

}



static inline struct bucket *gc_bucket(struct bch_dev *ca, size_t b)

{

	struct bucket_array *buckets = gc_bucket_array(ca);



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

		return NULL;

	return buckets->b + b;

	return genradix_ptr(&ca->buckets_gc, b);

}



static inline struct bucket_gens *bucket_gens(struct bch_dev *ca)

fs/bcachefs/buckets_types.h

+0 −8
Original line number Diff line number Diff line
@@ -19,14 +19,6 @@ struct bucket { 
	u32			stripe_sectors;

} __aligned(sizeof(long));



struct bucket_array {

	struct rcu_head		rcu;

	u16			first_bucket;

	size_t			nbuckets;

	size_t			nbuckets_minus_first;

	struct bucket		b[] __counted_by(nbuckets);

};



struct bucket_gens {

	struct rcu_head		rcu;

	u16			first_bucket;