[PATCH v2 06/10] mm/damon/sysfs-schemes: add a file for setting damos_filter->allow

[SeongJae Park <sj@kernel.org>]

Only kernel-space DAMON API users can use inclusive DAMOS filters.  Add
a sysfs file named 'allow' under DAMOS filter directory of DAMON sysfs
interface, to let the user-space users use inclusive DAMOS filters.

Signed-off-by: SeongJae Park <sj@kernel.org>
---
 mm/damon/sysfs-schemes.c | 32 +++++++++++++++++++++++++++++++-
 1 file changed, 31 insertions(+), 1 deletion(-)

diff --git a/mm/damon/sysfs-schemes.c b/mm/damon/sysfs-schemes.c
index 9a883e8aea1c..98f93ae9f59e 100644
--- a/mm/damon/sysfs-schemes.c
+++ b/mm/damon/sysfs-schemes.c
@@ -313,6 +313,7 @@ struct damon_sysfs_scheme_filter {
 	struct kobject kobj;
 	enum damos_filter_type type;
 	bool matching;
+	bool allow;
 	char *memcg_path;
 	struct damon_addr_range addr_range;
 	int target_idx;
@@ -385,6 +386,30 @@ static ssize_t matching_store(struct kobject *kobj,
 	return count;
 }
 
+static ssize_t allow_show(struct kobject *kobj,
+		struct kobj_attribute *attr, char *buf)
+{
+	struct damon_sysfs_scheme_filter *filter = container_of(kobj,
+			struct damon_sysfs_scheme_filter, kobj);
+
+	return sysfs_emit(buf, "%c\n", filter->allow ? 'Y' : 'N');
+}
+
+static ssize_t allow_store(struct kobject *kobj,
+		struct kobj_attribute *attr, const char *buf, size_t count)
+{
+	struct damon_sysfs_scheme_filter *filter = container_of(kobj,
+			struct damon_sysfs_scheme_filter, kobj);
+	bool allow;
+	int err = kstrtobool(buf, &allow);
+
+	if (err)
+		return err;
+
+	filter->allow = allow;
+	return count;
+}
+
 static ssize_t memcg_path_show(struct kobject *kobj,
 		struct kobj_attribute *attr, char *buf)
 {
@@ -482,6 +507,9 @@ static struct kobj_attribute damon_sysfs_scheme_filter_type_attr =
 static struct kobj_attribute damon_sysfs_scheme_filter_matching_attr =
 		__ATTR_RW_MODE(matching, 0600);
 
+static struct kobj_attribute damon_sysfs_scheme_filter_allow_attr =
+		__ATTR_RW_MODE(allow, 0600);
+
 static struct kobj_attribute damon_sysfs_scheme_filter_memcg_path_attr =
 		__ATTR_RW_MODE(memcg_path, 0600);
 
@@ -497,6 +525,7 @@ static struct kobj_attribute damon_sysfs_scheme_filter_damon_target_idx_attr =
 static struct attribute *damon_sysfs_scheme_filter_attrs[] = {
 	&damon_sysfs_scheme_filter_type_attr.attr,
 	&damon_sysfs_scheme_filter_matching_attr.attr,
+	&damon_sysfs_scheme_filter_allow_attr.attr,
 	&damon_sysfs_scheme_filter_memcg_path_attr.attr,
 	&damon_sysfs_scheme_filter_addr_start_attr.attr,
 	&damon_sysfs_scheme_filter_addr_end_attr.attr,
@@ -1901,7 +1930,8 @@ static int damon_sysfs_add_scheme_filters(struct damos *scheme,
 			sysfs_filters->filters_arr[i];
 		struct damos_filter *filter =
 			damos_new_filter(sysfs_filter->type,
-					sysfs_filter->matching, false);
+					sysfs_filter->matching,
+					sysfs_filter->allow);
 		int err;
 
 		if (!filter)
-- 
2.39.5