[PATCH 6.1.y] mm/damon/sysfs-scheme: cleanup access_pattern subdirs on scheme dir setup failure

[SeongJae Park <sj@kernel.org>]

When a DAMOS-scheme DAMON sysfs directory setup fails after setup of
access_pattern/ directory, subdirectories of access_pattern/ directory are
not cleaned up.  As a result, DAMON sysfs interface is nearly broken until
the system reboots, and the memory for the unremoved directory is leaked.

Cleanup the directories under such failures.

Link: https://lkml.kernel.org/r/20251225023043.18579-5-sj@kernel.org
Fixes: 9bbb820a5bd5 ("mm/damon/sysfs: support DAMOS quotas")
Signed-off-by: SeongJae Park <sj@kernel.org>
Cc: chongjiapeng <jiapeng.chong@linux.alibaba.com>
Cc: <stable@vger.kernel.org> # 5.18.x
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
(cherry picked from commit 392b3d9d595f34877dd745b470c711e8ebcd225c)
Signed-off-by: SeongJae Park <sj@kernel.org>
---
 mm/damon/sysfs.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/mm/damon/sysfs.c b/mm/damon/sysfs.c
index 18f459a3c9fff..1b85a0beeaaa4 100644
--- a/mm/damon/sysfs.c
+++ b/mm/damon/sysfs.c
@@ -856,7 +856,7 @@ static int damon_sysfs_scheme_add_dirs(struct damon_sysfs_scheme *scheme)
 		return err;
 	err = damon_sysfs_scheme_set_quotas(scheme);
 	if (err)
-		goto put_access_pattern_out;
+		goto rmdir_put_access_pattern_out;
 	err = damon_sysfs_scheme_set_watermarks(scheme);
 	if (err)
 		goto put_quotas_access_pattern_out;
@@ -871,7 +871,8 @@ static int damon_sysfs_scheme_add_dirs(struct damon_sysfs_scheme *scheme)
 put_quotas_access_pattern_out:
 	kobject_put(&scheme->quotas->kobj);
 	scheme->quotas = NULL;
-put_access_pattern_out:
+rmdir_put_access_pattern_out:
+	damon_sysfs_access_pattern_rm_dirs(scheme->access_pattern);
 	kobject_put(&scheme->access_pattern->kobj);
 	scheme->access_pattern = NULL;
 	return err;
-- 
2.47.3