[PATCH RFC v2 05/18] ext4: use anonymous devices for KUnit test superblocks

The mballoc and extents KUnit tests create superblocks through
sget_fc() with a set callback that never assigns s_dev and a kill_sb
that only calls generic_shutdown_super().

The upcoming global device-to-superblock table registers every
superblock under its s_dev, so each superblock needs a unique device
number. Allocate a proper anonymous device via set_anon_super_fc() and
release it through kill_anon_super().

Signed-off-by: Christian Brauner (Amutable) <[email protected]>
---
 fs/ext4/extents-test.c | 9 ++-------
 fs/ext4/mballoc-test.c | 9 ++-------
 2 files changed, 4 insertions(+), 14 deletions(-)

diff --git a/fs/ext4/extents-test.c b/fs/ext4/extents-test.c
index bd7795a82607..c3836ecb89f9 100644
--- a/fs/ext4/extents-test.c
+++ b/fs/ext4/extents-test.c
@@ -126,11 +126,6 @@ struct kunit_ext_test_param {
 	struct kunit_ext_data_state exp_data_state[3];
 };
 
-static void ext_kill_sb(struct super_block *sb)
-{
-	generic_shutdown_super(sb);
-}
-
 static int ext_init_fs_context(struct fs_context *fc)
 {
 	return 0;
@@ -138,13 +133,13 @@ static int ext_init_fs_context(struct fs_context *fc)
 
 static int ext_set(struct super_block *sb, struct fs_context *fc)
 {
-	return 0;
+	return set_anon_super_fc(sb, fc);
 }
 
 static struct file_system_type ext_fs_type = {
 	.name		 = "extents test",
 	.init_fs_context = ext_init_fs_context,
-	.kill_sb	 = ext_kill_sb,
+	.kill_sb	 = kill_anon_super,
 };
 
 static void extents_kunit_exit(struct kunit *test)
diff --git a/fs/ext4/mballoc-test.c b/fs/ext4/mballoc-test.c
index d90da44aadbd..a3b33ed2c172 100644
--- a/fs/ext4/mballoc-test.c
+++ b/fs/ext4/mballoc-test.c
@@ -59,11 +59,6 @@ static const struct super_operations mbt_sops = {
 	.free_inode	= mbt_free_inode,
 };
 
-static void mbt_kill_sb(struct super_block *sb)
-{
-	generic_shutdown_super(sb);
-}
-
 static int mbt_init_fs_context(struct fs_context *fc)
 {
 	return 0;
@@ -72,7 +67,7 @@ static int mbt_init_fs_context(struct fs_context *fc)
 static struct file_system_type mbt_fs_type = {
 	.name			= "mballoc test",
 	.init_fs_context	= mbt_init_fs_context,
-	.kill_sb		= mbt_kill_sb,
+	.kill_sb		= kill_anon_super,
 };
 
 static int mbt_mb_init(struct super_block *sb)
@@ -136,7 +131,7 @@ static void mbt_mb_release(struct super_block *sb)
 
 static int mbt_set(struct super_block *sb, struct fs_context *fc)
 {
-	return 0;
+	return set_anon_super_fc(sb, fc);
 }
 
 static struct super_block *mbt_ext4_alloc_super_block(void)

-- 
2.47.3