bcachefs: Kill writing old accounting to journal

More ripping out of the old disk space accounting.

Note that the new disk space accounting is incompatible with the old,
and writing out old style disk space accounting with the new code is
infeasible.

This means upgrading and downgrading past this version requires
regenerating accounting.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

fs/bcachefs/sb-clean.c

@@ -183,25 +183,6 @@ void bch2_journal_super_entries_add_common(struct bch_fs *c,
 					   struct jset_entry **end,
 					   u64 journal_seq)
 {
-	percpu_down_read(&c->mark_lock);
-
-	if (!journal_seq) {
-		for (unsigned i = 0; i < ARRAY_SIZE(c->usage); i++)
-			bch2_fs_usage_acc_to_base(c, i);
-	} else {
-		bch2_fs_usage_acc_to_base(c, journal_seq & JOURNAL_BUF_MASK);
-	}
-
-	{
-		struct jset_entry_usage *u =
-			container_of(jset_entry_init(end, sizeof(*u)),
-				     struct jset_entry_usage, entry);
-
-		u->entry.type	= BCH_JSET_ENTRY_usage;
-		u->entry.btree_id = BCH_FS_USAGE_inodes;
-		u->v		= cpu_to_le64(c->usage_base->b.nr_inodes);
-	}
-
 	{
 		struct jset_entry_usage *u =
 			container_of(jset_entry_init(end, sizeof(*u)),
@@ -212,32 +193,6 @@ void bch2_journal_super_entries_add_common(struct bch_fs *c,
 		u->v		= cpu_to_le64(atomic64_read(&c->key_version));
 	}
 
-	for (unsigned i = 0; i < BCH_REPLICAS_MAX; i++) {
-		struct jset_entry_usage *u =
-			container_of(jset_entry_init(end, sizeof(*u)),
-				     struct jset_entry_usage, entry);
-
-		u->entry.type	= BCH_JSET_ENTRY_usage;
-		u->entry.btree_id = BCH_FS_USAGE_reserved;
-		u->entry.level	= i;
-		u->v		= cpu_to_le64(c->usage_base->persistent_reserved[i]);
-	}
-
-	for (unsigned i = 0; i < c->replicas.nr; i++) {
-		struct bch_replicas_entry_v1 *e =
-			cpu_replicas_entry(&c->replicas, i);
-		struct jset_entry_data_usage *u =
-			container_of(jset_entry_init(end, sizeof(*u) + e->nr_devs),
-				     struct jset_entry_data_usage, entry);
-
-		u->entry.type	= BCH_JSET_ENTRY_data_usage;
-		u->v		= cpu_to_le64(c->usage_base->replicas[i]);
-		unsafe_memcpy(&u->r, e, replicas_entry_bytes(e),
-			      "embedded variable length struct");
-	}
-
-	percpu_up_read(&c->mark_lock);
-
 	for (unsigned i = 0; i < 2; i++) {
 		struct jset_entry_clock *clock =
 			container_of(jset_entry_init(end, sizeof(*clock)),