bcachefs: New helpers for device refcounts

This will be used in the next patch for adding some new debug mode
asserts.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

fs/bcachefs/alloc_background.c

@@ -1656,10 +1656,9 @@ static void discard_buckets_next_dev(struct bch_fs *c, struct discard_buckets_st
 	    bch2_dev_usage_read(s->ca).d[BCH_DATA_free].buckets)
 		bch2_journal_flush_async(&c->journal, NULL);
 
-	if (s->ca)
-		percpu_ref_put(&s->ca->ref);
+	bch2_dev_put(s->ca);
 	if (ca)
-		percpu_ref_get(&ca->ref);
+		bch2_dev_get(ca);
 	s->ca = ca;
 	s->need_journal_commit_this_dev = 0;
 }
@@ -2014,7 +2013,7 @@ static void bch2_do_invalidates_work(struct work_struct *work)
 			invalidate_one_bucket(trans, &iter, k, &nr_to_invalidate));
 
 		if (ret < 0) {
-			percpu_ref_put(&ca->ref);
+			bch2_dev_put(ca);
 			break;
 		}
 	}
@@ -2151,7 +2150,7 @@ int bch2_fs_freespace_init(struct bch_fs *c)
 
 		ret = bch2_dev_freespace_init(c, ca, 0, ca->mi.nbuckets);
 		if (ret) {
-			percpu_ref_put(&ca->ref);
+			bch2_dev_put(ca);
 			bch_err_fn(c, ret);
 			return ret;
 		}

fs/bcachefs/alloc_foreground.c

@@ -733,21 +733,21 @@ int bch2_bucket_alloc_set_trans(struct btree_trans *trans,
 		rcu_read_lock();
 		ca = rcu_dereference(c->devs[dev]);
 		if (ca)
-			percpu_ref_get(&ca->ref);
+			bch2_dev_get(ca);
 		rcu_read_unlock();
 
 		if (!ca)
 			continue;
 
 		if (!ca->mi.durability && *have_cache) {
-			percpu_ref_put(&ca->ref);
+			bch2_dev_put(ca);
 			continue;
 		}
 
 		ob = bch2_bucket_alloc_trans(trans, ca, watermark, data_type, cl, &usage);
 		if (!IS_ERR(ob))
 			bch2_dev_stripe_increment_inlined(ca, stripe, &usage);
-		percpu_ref_put(&ca->ref);
+		bch2_dev_put(ca);
 
 		if (IS_ERR(ob)) {
 			ret = PTR_ERR(ob);

fs/bcachefs/btree_gc.c

@@ -815,10 +815,8 @@ static int bch2_gc_done(struct bch_fs *c)
 #undef copy_stripe_field
 #undef copy_field
 fsck_err:
-	if (ca)
-		percpu_ref_put(&ca->ref);
+	bch2_dev_put(ca);
 	bch_err_fn(c, ret);
-
 	percpu_up_write(&c->mark_lock);
 	printbuf_exit(&buf);
 	return ret;
@@ -841,7 +839,7 @@ static int bch2_gc_start(struct bch_fs *c)
 		ca->usage_gc = alloc_percpu(struct bch_dev_usage);
 		if (!ca->usage_gc) {
 			bch_err(c, "error allocating ca->usage_gc");
-			percpu_ref_put(&ca->ref);
+			bch2_dev_put(ca);
 			return -BCH_ERR_ENOMEM_gc_start;
 		}
 
@@ -969,7 +967,7 @@ static int bch2_gc_alloc_done(struct bch_fs *c)
 					NULL, NULL, BCH_TRANS_COMMIT_lazy_rw,
 				bch2_alloc_write_key(trans, &iter, k)));
 		if (ret) {
-			percpu_ref_put(&ca->ref);
+			bch2_dev_put(ca);
 			break;
 		}
 	}
@@ -985,7 +983,7 @@ static int bch2_gc_alloc_start(struct bch_fs *c)
 				ca->mi.nbuckets * sizeof(struct bucket),
 				GFP_KERNEL|__GFP_ZERO);
 		if (!buckets) {
-			percpu_ref_put(&ca->ref);
+			bch2_dev_put(ca);
 			bch_err(c, "error allocating ca->buckets[gc]");
 			return -BCH_ERR_ENOMEM_gc_alloc_start;
 		}
@@ -1330,7 +1328,7 @@ int bch2_gc_gens(struct bch_fs *c)
 
 		ca->oldest_gen = kvmalloc(gens->nbuckets, GFP_KERNEL);
 		if (!ca->oldest_gen) {
-			percpu_ref_put(&ca->ref);
+			bch2_dev_put(ca);
 			ret = -BCH_ERR_ENOMEM_gc_gens;
 			goto err;
 		}

fs/bcachefs/buckets.c

@@ -1438,7 +1438,7 @@ int bch2_trans_mark_dev_sbs_flags(struct bch_fs *c,
 	for_each_online_member(c, ca) {
 		int ret = bch2_trans_mark_dev_sb(c, ca, flags);
 		if (ret) {
-			percpu_ref_put(&ca->ref);
+			bch2_dev_put(ca);
 			return ret;
 		}
 	}
@@ -1536,7 +1536,7 @@ int bch2_buckets_nouse_alloc(struct bch_fs *c)
 					    sizeof(unsigned long),
 					    GFP_KERNEL|__GFP_ZERO);
 		if (!ca->buckets_nouse) {
-			percpu_ref_put(&ca->ref);
+			bch2_dev_put(ca);
 			return -BCH_ERR_ENOMEM_buckets_nouse;
 		}
 	}

fs/bcachefs/chardev.c

@@ -35,7 +35,7 @@ static struct bch_dev *bch2_device_lookup(struct bch_fs *c, u64 dev,
 		rcu_read_lock();
 		ca = rcu_dereference(c->devs[dev]);
 		if (ca)
-			percpu_ref_get(&ca->ref);
+			bch2_dev_get(ca);
 		rcu_read_unlock();
 
 		if (!ca)
@@ -391,7 +391,7 @@ static long bch2_ioctl_disk_offline(struct bch_fs *c, struct bch_ioctl_disk arg)
 		return PTR_ERR(ca);
 
 	ret = bch2_dev_offline(c, ca, arg.flags);
-	percpu_ref_put(&ca->ref);
+	bch2_dev_put(ca);
 	return ret;
 }
 
@@ -420,7 +420,7 @@ static long bch2_ioctl_disk_set_state(struct bch_fs *c,
 	if (ret)
 		bch_err(c, "Error setting device state: %s", bch2_err_str(ret));
 
-	percpu_ref_put(&ca->ref);
+	bch2_dev_put(ca);
 	return ret;
 }
 
@@ -615,7 +615,7 @@ static long bch2_ioctl_dev_usage(struct bch_fs *c,
 		arg.d[i].fragmented	= src.d[i].fragmented;
 	}
 
-	percpu_ref_put(&ca->ref);
+	bch2_dev_put(ca);
 
 	return copy_to_user_errcode(user_arg, &arg, sizeof(arg));
 }
@@ -667,7 +667,7 @@ static long bch2_ioctl_dev_usage_v2(struct bch_fs *c,
 			goto err;
 	}
 err:
-	percpu_ref_put(&ca->ref);
+	bch2_dev_put(ca);
 	return ret;
 }
 
@@ -689,11 +689,9 @@ static long bch2_ioctl_read_super(struct bch_fs *c,
 
 	if (arg.flags & BCH_READ_DEV) {
 		ca = bch2_device_lookup(c, arg.dev, arg.flags);
-
-		if (IS_ERR(ca)) {
-			ret = PTR_ERR(ca);
-			goto err;
-		}
+		ret = PTR_ERR_OR_ZERO(ca);
+		if (ret)
+			goto err_unlock;
 
 		sb = ca->disk_sb.sb;
 	} else {
@@ -708,8 +706,8 @@ static long bch2_ioctl_read_super(struct bch_fs *c,
 	ret = copy_to_user_errcode((void __user *)(unsigned long)arg.sb, sb,
 				   vstruct_bytes(sb));
 err:
-	if (!IS_ERR_OR_NULL(ca))
-		percpu_ref_put(&ca->ref);
+	bch2_dev_put(ca);
+err_unlock:
 	mutex_unlock(&c->sb_lock);
 	return ret;
 }
@@ -753,7 +751,7 @@ static long bch2_ioctl_disk_resize(struct bch_fs *c,
 
 	ret = bch2_dev_resize(c, ca, arg.nbuckets);
 
-	percpu_ref_put(&ca->ref);
+	bch2_dev_put(ca);
 	return ret;
 }
 
@@ -779,7 +777,7 @@ static long bch2_ioctl_disk_resize_journal(struct bch_fs *c,
 
 	ret = bch2_set_nr_journal_buckets(c, ca, arg.nbuckets);
 
-	percpu_ref_put(&ca->ref);
+	bch2_dev_put(ca);
 	return ret;
 }
 

fs/bcachefs/data_update.c

@@ -360,7 +360,7 @@ void bch2_data_update_exit(struct data_update *update)
 		if (c->opts.nocow_enabled)
 			bch2_bucket_nocow_unlock(&c->nocow_locks,
 						 PTR_BUCKET_POS(c, ptr), 0);
-		percpu_ref_put(&bch2_dev_bkey_exists(c, ptr->dev)->ref);
+		bch2_dev_put(bch2_dev_bkey_exists(c, ptr->dev));
 	}
 
 	bch2_bkey_buf_exit(&update->k, c);
@@ -541,7 +541,7 @@ int bch2_data_update_init(struct btree_trans *trans,
 	m->op.watermark		= m->data_opts.btree_insert_flags & BCH_WATERMARK_MASK;
 
 	bkey_for_each_ptr(ptrs, ptr)
-		percpu_ref_get(&bch2_dev_bkey_exists(c, ptr->dev)->ref);
+		bch2_dev_get(bch2_dev_bkey_exists(c, ptr->dev));
 
 	unsigned durability_have = 0, durability_removing = 0;
 
@@ -653,7 +653,7 @@ int bch2_data_update_init(struct btree_trans *trans,
 		if ((1U << i) & ptrs_locked)
 			bch2_bucket_nocow_unlock(&c->nocow_locks,
 						 PTR_BUCKET_POS(c, &p.ptr), 0);
-		percpu_ref_put(&bch2_dev_bkey_exists(c, p.ptr.dev)->ref);
+		bch2_dev_put(bch2_dev_bkey_exists(c, p.ptr.dev));
 		i++;
 	}
 

fs/bcachefs/disk_groups.c

@@ -523,7 +523,7 @@ int bch2_opt_target_parse(struct bch_fs *c, const char *val, u64 *res,
 	ca = bch2_dev_lookup(c, val);
 	if (!IS_ERR(ca)) {
 		*res = dev_to_target(ca->dev_idx);
-		percpu_ref_put(&ca->ref);
+		bch2_dev_put(ca);
 		return 0;
 	}
 

fs/bcachefs/sb-members.h

@@ -105,14 +105,28 @@ static inline struct bch_dev *__bch2_next_dev(struct bch_fs *c, struct bch_dev *
 	for (struct bch_dev *_ca = NULL;				\
 	     (_ca = __bch2_next_dev((_c), _ca, (_mask)));)
 
-static inline struct bch_dev *bch2_get_next_dev(struct bch_fs *c, struct bch_dev *ca)
+static inline void bch2_dev_get(struct bch_dev *ca)
+{
+	percpu_ref_get(&ca->ref);
+}
+
+static inline void __bch2_dev_put(struct bch_dev *ca)
+{
+	percpu_ref_put(&ca->ref);
+}
+
+static inline void bch2_dev_put(struct bch_dev *ca)
 {
-	rcu_read_lock();
 	if (ca)
-		percpu_ref_put(&ca->ref);
+		__bch2_dev_put(ca);
+}
 
+static inline struct bch_dev *bch2_get_next_dev(struct bch_fs *c, struct bch_dev *ca)
+{
+	rcu_read_lock();
+	bch2_dev_put(ca);
 	if ((ca = __bch2_next_dev(c, ca, NULL)))
-		percpu_ref_get(&ca->ref);
+		bch2_dev_get(ca);
 	rcu_read_unlock();
 
 	return ca;

fs/bcachefs/super.c

@@ -710,7 +710,7 @@ static int bch2_fs_online(struct bch_fs *c)
 		ret = bch2_dev_sysfs_online(c, ca);
 		if (ret) {
 			bch_err(c, "error creating sysfs objects");
-			percpu_ref_put(&ca->ref);
+			bch2_dev_put(ca);
 			goto err;
 		}
 	}
@@ -1613,7 +1613,7 @@ int bch2_dev_remove(struct bch_fs *c, struct bch_dev *ca, int flags)
 	 * We consume a reference to ca->ref, regardless of whether we succeed
 	 * or fail:
 	 */
-	percpu_ref_put(&ca->ref);
+	bch2_dev_put(ca);
 
 	if (!bch2_dev_state_allowed(c, ca, BCH_MEMBER_STATE_failed, flags)) {
 		bch_err(ca, "Cannot remove without losing data");