diff --git a/fs/bcachefs/chardev.c b/fs/bcachefs/chardev.c
index 7fd80f6de221..77d7186b4ba3 100644
--- a/fs/bcachefs/chardev.c
+++ b/fs/bcachefs/chardev.c
@@ -227,7 +227,7 @@ static long bch2_ioctl_fsck_offline(struct bch_ioctl_fsck_offline __user *user_a
 		}
 
 		ret =   PTR_ERR_OR_ZERO(optstr) ?:
-			bch2_parse_mount_opts(NULL, &thr->opts, optstr);
+			bch2_parse_mount_opts(NULL, &thr->opts, NULL, optstr);
 		if (!IS_ERR(optstr))
 			kfree(optstr);
 
@@ -864,7 +864,7 @@ static long bch2_ioctl_fsck_online(struct bch_fs *c,
 		char *optstr = strndup_user((char __user *)(unsigned long) arg.opts, 1 << 16);
 
 		ret =   PTR_ERR_OR_ZERO(optstr) ?:
-			bch2_parse_mount_opts(c, &thr->opts, optstr);
+			bch2_parse_mount_opts(c, &thr->opts, NULL, optstr);
 		if (!IS_ERR(optstr))
 			kfree(optstr);
 
diff --git a/fs/bcachefs/fs.c b/fs/bcachefs/fs.c
index 78f2d80b8bb7..d2fccdc6524f 100644
--- a/fs/bcachefs/fs.c
+++ b/fs/bcachefs/fs.c
@@ -1730,7 +1730,7 @@ static int bch2_remount(struct super_block *sb, int *flags, char *data)
 	struct bch_opts opts = bch2_opts_empty();
 	int ret;
 
-	ret = bch2_parse_mount_opts(c, &opts, data);
+	ret = bch2_parse_mount_opts(c, &opts, NULL, data);
 	if (ret)
 		goto err;
 
@@ -1903,7 +1903,7 @@ static struct dentry *bch2_mount(struct file_system_type *fs_type,
 
 	opt_set(opts, read_only, (flags & SB_RDONLY) != 0);
 
-	ret = bch2_parse_mount_opts(NULL, &opts, data);
+	ret = bch2_parse_mount_opts(NULL, &opts, NULL, data);
 	if (ret) {
 		ret = bch2_err_class(ret);
 		return ERR_PTR(ret);
@@ -1937,7 +1937,7 @@ static struct dentry *bch2_mount(struct file_system_type *fs_type,
 	}
 
 	/* Some options can't be parsed until after the fs is started: */
-	ret = bch2_parse_mount_opts(c, &opts, data);
+	ret = bch2_parse_mount_opts(c, &opts, NULL, data);
 	if (ret) {
 		bch2_fs_stop(c);
 		sb = ERR_PTR(ret);
diff --git a/fs/bcachefs/opts.c b/fs/bcachefs/opts.c
index bb068fd72465..e794706276cf 100644
--- a/fs/bcachefs/opts.c
+++ b/fs/bcachefs/opts.c
@@ -460,14 +460,70 @@ int bch2_opts_check_may_set(struct bch_fs *c)
 	return 0;
 }
 
+int bch2_parse_one_mount_opt(struct bch_fs *c, struct bch_opts *opts,
+			     struct printbuf *parse_later,
+			     const char *name, const char *val)
+{
+	struct printbuf err = PRINTBUF;
+	u64 v;
+	int ret, id;
+
+	id = bch2_mount_opt_lookup(name);
+
+	/* Check for the form "noopt", negation of a boolean opt: */
+	if (id < 0 &&
+	    !val &&
+	    !strncmp("no", name, 2)) {
+		id = bch2_mount_opt_lookup(name + 2);
+		val = "0";
+	}
+
+	/* Unknown options are ignored: */
+	if (id < 0)
+		return 0;
+
+	if (!(bch2_opt_table[id].flags & OPT_MOUNT))
+		goto bad_opt;
+
+	if (id == Opt_acl &&
+	    !IS_ENABLED(CONFIG_BCACHEFS_POSIX_ACL))
+		goto bad_opt;
+
+	if ((id == Opt_usrquota ||
+	     id == Opt_grpquota) &&
+	    !IS_ENABLED(CONFIG_BCACHEFS_QUOTA))
+		goto bad_opt;
+
+	ret = bch2_opt_parse(c, &bch2_opt_table[id], val, &v, &err);
+	if (ret < 0)
+		goto bad_val;
+
+	if (opts)
+		bch2_opt_set_by_id(opts, id, v);
+
+	ret = 0;
+	goto out;
+
+bad_opt:
+	pr_err("Bad mount option %s", name);
+	ret = -BCH_ERR_option_name;
+	goto out;
+
+bad_val:
+	pr_err("Invalid mount option %s", err.buf);
+	ret = -BCH_ERR_option_value;
+
+out:
+	printbuf_exit(&err);
+	return ret;
+}
+
 int bch2_parse_mount_opts(struct bch_fs *c, struct bch_opts *opts,
-			  char *options)
+			  struct printbuf *parse_later, char *options)
 {
 	char *copied_opts, *copied_opts_start;
 	char *opt, *name, *val;
-	int ret, id;
-	struct printbuf err = PRINTBUF;
-	u64 v;
+	int ret;
 
 	if (!options)
 		return 0;
@@ -488,53 +544,16 @@ int bch2_parse_mount_opts(struct bch_fs *c, struct bch_opts *opts,
 		name	= strsep(&opt, "=");
 		val	= opt;
 
-		id = bch2_mount_opt_lookup(name);
-
-		/* Check for the form "noopt", negation of a boolean opt: */
-		if (id < 0 &&
-		    !val &&
-		    !strncmp("no", name, 2)) {
-			id = bch2_mount_opt_lookup(name + 2);
-			val = "0";
-		}
-
-		/* Unknown options are ignored: */
-		if (id < 0)
-			continue;
-
-		if (!(bch2_opt_table[id].flags & OPT_MOUNT))
-			goto bad_opt;
-
-		if (id == Opt_acl &&
-		    !IS_ENABLED(CONFIG_BCACHEFS_POSIX_ACL))
-			goto bad_opt;
-
-		if ((id == Opt_usrquota ||
-		     id == Opt_grpquota) &&
-		    !IS_ENABLED(CONFIG_BCACHEFS_QUOTA))
-			goto bad_opt;
-
-		ret = bch2_opt_parse(c, &bch2_opt_table[id], val, &v, &err);
+		ret = bch2_parse_one_mount_opt(c, opts, parse_later, name, val);
 		if (ret < 0)
-			goto bad_val;
-
-		bch2_opt_set_by_id(opts, id, v);
+			goto out;
 	}
 
 	ret = 0;
 	goto out;
 
-bad_opt:
-	pr_err("Bad mount option %s", name);
-	ret = -BCH_ERR_option_name;
-	goto out;
-bad_val:
-	pr_err("Invalid mount option %s", err.buf);
-	ret = -BCH_ERR_option_value;
-	goto out;
 out:
 	kfree(copied_opts_start);
-	printbuf_exit(&err);
 	return ret;
 }
 
diff --git a/fs/bcachefs/opts.h b/fs/bcachefs/opts.h
index c9da6267894b..edd509561ea2 100644
--- a/fs/bcachefs/opts.h
+++ b/fs/bcachefs/opts.h
@@ -566,7 +566,10 @@ void bch2_opt_to_text(struct printbuf *, struct bch_fs *, struct bch_sb *,
 
 int bch2_opt_check_may_set(struct bch_fs *, int, u64);
 int bch2_opts_check_may_set(struct bch_fs *);
-int bch2_parse_mount_opts(struct bch_fs *, struct bch_opts *, char *);
+int bch2_parse_one_mount_opt(struct bch_fs *, struct bch_opts *,
+			     struct printbuf *, const char *, const char *);
+int bch2_parse_mount_opts(struct bch_fs *, struct bch_opts *, struct printbuf *,
+			  char *);
 
 /* inode opts: */