1 files changed, 44 insertions, 4 deletions

diff --git a/mm/damon/sysfs.c b/mm/damon/sysfs.c
index c96c2154128f..2fc722f998f8 100644
--- a/mm/damon/sysfs.c
+++ b/mm/damon/sysfs.c
@@ -834,6 +834,7 @@ static const struct damon_sysfs_ops_name damon_sysfs_ops_names[] = {
 struct damon_sysfs_context {
 	struct kobject kobj;
 	enum damon_ops_id ops_id;
+	unsigned long addr_unit;
 	struct damon_sysfs_attrs *attrs;
 	struct damon_sysfs_targets *targets;
 	struct damon_sysfs_schemes *schemes;
@@ -849,6 +850,7 @@ static struct damon_sysfs_context *damon_sysfs_context_alloc(
 		return NULL;
 	context->kobj = (struct kobject){};
 	context->ops_id = ops_id;
+	context->addr_unit = 1;
 	return context;
 }
 
@@ -997,6 +999,32 @@ static ssize_t operations_store(struct kobject *kobj,
 	return -EINVAL;
 }
 
+static ssize_t addr_unit_show(struct kobject *kobj,
+		struct kobj_attribute *attr, char *buf)
+{
+	struct damon_sysfs_context *context = container_of(kobj,
+			struct damon_sysfs_context, kobj);
+
+	return sysfs_emit(buf, "%lu\n", context->addr_unit);
+}
+
+static ssize_t addr_unit_store(struct kobject *kobj,
+		struct kobj_attribute *attr, const char *buf, size_t count)
+{
+	struct damon_sysfs_context *context = container_of(kobj,
+			struct damon_sysfs_context, kobj);
+	unsigned long input_addr_unit;
+	int err = kstrtoul(buf, 0, &input_addr_unit);
+
+	if (err)
+		return err;
+	if (!input_addr_unit)
+		return -EINVAL;
+
+	context->addr_unit = input_addr_unit;
+	return count;
+}
+
 static void damon_sysfs_context_release(struct kobject *kobj)
 {
 	kfree(container_of(kobj, struct damon_sysfs_context, kobj));
@@ -1008,9 +1036,13 @@ static struct kobj_attribute damon_sysfs_context_avail_operations_attr =
 static struct kobj_attribute damon_sysfs_context_operations_attr =
 		__ATTR_RW_MODE(operations, 0600);
 
+static struct kobj_attribute damon_sysfs_context_addr_unit_attr =
+		__ATTR_RW_MODE(addr_unit, 0600);
+
 static struct attribute *damon_sysfs_context_attrs[] = {
 	&damon_sysfs_context_avail_operations_attr.attr,
 	&damon_sysfs_context_operations_attr.attr,
+	&damon_sysfs_context_addr_unit_attr.attr,
 	NULL,
 };
 ATTRIBUTE_GROUPS(damon_sysfs_context);
@@ -1301,7 +1333,8 @@ static int damon_sysfs_set_attrs(struct damon_ctx *ctx,
 }
 
 static int damon_sysfs_set_regions(struct damon_target *t,
-		struct damon_sysfs_regions *sysfs_regions)
+		struct damon_sysfs_regions *sysfs_regions,
+		unsigned long min_sz_region)
 {
 	struct damon_addr_range *ranges = kmalloc_array(sysfs_regions->nr,
 			sizeof(*ranges), GFP_KERNEL | __GFP_NOWARN);
@@ -1323,7 +1356,7 @@ static int damon_sysfs_set_regions(struct damon_target *t,
 		if (ranges[i - 1].end > ranges[i].start)
 			goto out;
 	}
-	err = damon_set_regions(t, ranges, sysfs_regions->nr);
+	err = damon_set_regions(t, ranges, sysfs_regions->nr, min_sz_region);
 out:
 	kfree(ranges);
 	return err;
@@ -1344,7 +1377,7 @@ static int damon_sysfs_add_target(struct damon_sysfs_target *sys_target,
 			/* caller will destroy targets */
 			return -EINVAL;
 	}
-	return damon_sysfs_set_regions(t, sys_target->regions);
+	return damon_sysfs_set_regions(t, sys_target->regions, ctx->min_sz_region);
 }
 
 static int damon_sysfs_add_targets(struct damon_ctx *ctx,
@@ -1401,6 +1434,11 @@ static int damon_sysfs_apply_inputs(struct damon_ctx *ctx,
 	err = damon_select_ops(ctx, sys_ctx->ops_id);
 	if (err)
 		return err;
+	ctx->addr_unit = sys_ctx->addr_unit;
+	/* addr_unit is respected by only DAMON_OPS_PADDR */
+	if (sys_ctx->ops_id == DAMON_OPS_PADDR)
+		ctx->min_sz_region = max(
+				DAMON_MIN_REGION / sys_ctx->addr_unit, 1);
 	err = damon_sysfs_set_attrs(ctx, sys_ctx->attrs);
 	if (err)
 		return err;
@@ -1592,12 +1630,14 @@ static int damon_sysfs_damon_call(int (*fn)(void *data),
 		struct damon_sysfs_kdamond *kdamond)
 {
 	struct damon_call_control call_control = {};
+	int err;
 
 	if (!kdamond->damon_ctx)
 		return -EINVAL;
 	call_control.fn = fn;
 	call_control.data = kdamond;
-	return damon_call(kdamond->damon_ctx, &call_control);
+	err = damon_call(kdamond->damon_ctx, &call_control);
+	return err ? err : call_control.return_code;
 }
 
 struct damon_sysfs_schemes_walk_data {