bcachefs: Fix key cache assertion

Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

fs/bcachefs/bcachefs.h

@@ -489,6 +489,7 @@ enum {
 	BCH_FS_FSCK_DONE,
 	BCH_FS_STARTED,
 	BCH_FS_RW,
+	BCH_FS_WAS_RW,
 
 	/* shutdown: */
 	BCH_FS_STOPPING,

fs/bcachefs/btree_key_cache.c

@@ -683,7 +683,9 @@ void bch2_fs_btree_key_cache_exit(struct btree_key_cache *bc)
 		kmem_cache_free(bch2_key_cache, ck);
 	}
 
-	BUG_ON(atomic_long_read(&bc->nr_dirty) && !bch2_journal_error(&c->journal));
+	BUG_ON(atomic_long_read(&bc->nr_dirty) &&
+	       !bch2_journal_error(&c->journal) &&
+	       test_bit(BCH_FS_WAS_RW, &c->flags));
 	BUG_ON(atomic_long_read(&bc->nr_keys));
 
 	mutex_unlock(&bc->lock);

fs/bcachefs/recovery.c

@@ -973,7 +973,7 @@ int bch2_fs_recovery(struct bch_fs *c)
 	struct jset *last_journal_entry = NULL;
 	u64 blacklist_seq, journal_seq;
 	bool write_sb = false;
-	int ret;
+	int ret = 0;
 
 	if (c->sb.clean)
 		clean = read_superblock_clean(c);
@@ -1253,10 +1253,9 @@ int bch2_fs_recovery(struct bch_fs *c)
 	if (c->journal_seq_blacklist_table &&
 	    c->journal_seq_blacklist_table->nr > 128)
 		queue_work(system_long_wq, &c->journal_seq_blacklist_gc_work);
-out:
+
 	ret = 0;
-err:
-fsck_err:
+out:
 	set_bit(BCH_FS_FSCK_DONE, &c->flags);
 	bch2_flush_fsck_errs(c);
 
@@ -1270,6 +1269,10 @@ int bch2_fs_recovery(struct bch_fs *c)
 	else
 		bch_verbose(c, "ret %i", ret);
 	return ret;
+err:
+fsck_err:
+	bch2_fs_emergency_read_only(c);
+	goto out;
 }
 
 int bch2_fs_initialize(struct bch_fs *c)

fs/bcachefs/super.c

@@ -441,6 +441,7 @@ static int __bch2_fs_read_write(struct bch_fs *c, bool early)
 
 	percpu_ref_reinit(&c->writes);
 	set_bit(BCH_FS_RW, &c->flags);
+	set_bit(BCH_FS_WAS_RW, &c->flags);
 	return 0;
 err:
 	__bch2_fs_read_only(c);