From: Kent Overstreet <kent.overstreet@linux.dev>
Date: Sat, 6 Jan 2024 00:04:42 +0000 (-0500)
Subject: bcachefs: fix simulateously upgrading & downgrading
X-Git-Tag: v6.8-rc1~137^2~2
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=e7999235e6c437b99fad03d8301a4341be0d2bb5;p=thirdparty%2Flinux.git

bcachefs: fix simulateously upgrading & downgrading

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

diff --git a/fs/bcachefs/super-io.c b/fs/bcachefs/super-io.c
index c05983fe68155..55926b81eede6 100644
--- a/fs/bcachefs/super-io.c
+++ b/fs/bcachefs/super-io.c
@@ -1088,13 +1088,22 @@ bool bch2_check_version_downgrade(struct bch_fs *c)
 	/*
 	 * Downgrade, if superblock is at a higher version than currently
 	 * supported:
+	 *
+	 * c->sb will be checked before we write the superblock, so update it as
+	 * well:
 	 */
-	if (BCH_SB_VERSION_UPGRADE_COMPLETE(c->disk_sb.sb) > bcachefs_metadata_version_current)
+	if (BCH_SB_VERSION_UPGRADE_COMPLETE(c->disk_sb.sb) > bcachefs_metadata_version_current) {
 		SET_BCH_SB_VERSION_UPGRADE_COMPLETE(c->disk_sb.sb, bcachefs_metadata_version_current);
-	if (c->sb.version > bcachefs_metadata_version_current)
+		c->sb.version_upgrade_complete = bcachefs_metadata_version_current;
+	}
+	if (c->sb.version > bcachefs_metadata_version_current) {
 		c->disk_sb.sb->version = cpu_to_le16(bcachefs_metadata_version_current);
-	if (c->sb.version_min > bcachefs_metadata_version_current)
+		c->sb.version = bcachefs_metadata_version_current;
+	}
+	if (c->sb.version_min > bcachefs_metadata_version_current) {
 		c->disk_sb.sb->version_min = cpu_to_le16(bcachefs_metadata_version_current);
+		c->sb.version_min = bcachefs_metadata_version_current;
+	}
 	c->disk_sb.sb->compat[0] &= cpu_to_le64((1ULL << BCH_COMPAT_NR) - 1);
 	return ret;
 }