arm64/mpam: resctrl: Update resources reset process

hulk inclusion
category: feature
feature: ARM MPAM support
bugzilla: 48265
CVE: NA

--------------------------------

resctrl_resource_reset() would be excuted if resctrl sysfs umount, this
help to reset all settings stored in related structures (such as mpam_cfg)
and put MSCs back to default state.

This is similar to 6ab0b81f2c18 ("arm64/mpam: Fix unreset resources when mkdir
ctrl group or umount resctrl") but using helpers from mpam devices module.
Signed-off-by: NWang ShaoBo <bobo.shaobowang@huawei.com>
Reviewed-by: NXiongfeng Wang <wangxiongfeng2@huawei.com>
Reviewed-by: NCheng Jian <cj.chengjian@huawei.com>
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>

arch/arm64/kernel/mpam/mpam_device.c

@@ -1292,6 +1292,22 @@ int mpam_component_config(struct mpam_component *comp, struct sync_args *args)
 	return do_device_sync(comp, &sync_ctx);
 }
 
+/*
+ * Reset every component, configuring every partid unrestricted.
+ */
+void mpam_reset_devices(void)
+{
+	struct mpam_class *class;
+	struct mpam_component *comp;
+
+	mutex_lock(&mpam_devices_lock);
+	list_for_each_entry(class, &mpam_classes, classes_list) {
+		list_for_each_entry(comp, &class->components, class_list)
+			mpam_component_config(comp, NULL);
+	}
+	mutex_unlock(&mpam_devices_lock);
+}
+
 static inline void
 mpam_device_sync_mon_prepare(struct mpam_component *comp,
 		struct mpam_device_sync *sync_ctx, struct sync_args *args)

arch/arm64/kernel/mpam/mpam_internal.h

@@ -159,6 +159,8 @@ static inline bool mpam_has_part_sel(mpam_features_t supported)
 int mpam_component_config(struct mpam_component *comp,
 			struct sync_args *args);
 
+void mpam_reset_devices(void);
+
 int mpam_component_mon(struct mpam_component *comp,
 			struct sync_args *args, u64 *result);
 

arch/arm64/kernel/mpam/mpam_resctrl.c

@@ -526,25 +526,6 @@ void post_resctrl_mount(void)
 		static_branch_enable_cpuslocked(&resctrl_enable_key);
 }
 
-static int reset_all_ctrls(struct resctrl_resource *r)
-{
-	return 0;
-}
-
-void resctrl_resource_reset(void)
-{
-	struct mpam_resctrl_res *res;
-	struct resctrl_resource *r;
-
-	/*Put everything back to default values. */
-	for_each_supported_resctrl_exports(res) {
-		r = &res->resctrl_res;
-
-		if (r->alloc_enabled)
-			reset_all_ctrls(r);
-	}
-}
-
 void release_rdtgroupfs_options(void)
 {
 }
@@ -1498,6 +1479,45 @@ mpam_resctrl_update_component_cfg(struct resctrl_resource *r,
 	mpam_update_from_resctrl_cfg(res, resctrl_cfg, mpam_cfg);
 }
 
+static void mpam_reset_cfg(struct mpam_resctrl_res *res,
+		struct mpam_resctrl_dom *dom, struct rdt_domain *d)
+
+{
+	int i;
+	struct resctrl_resource *r = &res->resctrl_res;
+
+	for (i = 0; i != mpam_sysprops_num_partid(); i++) {
+		mpam_update_from_resctrl_cfg(res, r->default_ctrl,
+			&dom->comp->cfg[i]);
+		d->ctrl_val[i] = r->default_ctrl;
+	}
+}
+
+void resctrl_resource_reset(void)
+{
+	struct mpam_resctrl_res *res;
+	struct mpam_resctrl_dom *dom;
+	struct rdt_domain *d;
+
+	for_each_supported_resctrl_exports(res) {
+		if (!res->resctrl_res.alloc_capable)
+			continue;
+
+		list_for_each_entry(d, &res->resctrl_res.domains, list) {
+			dom = container_of(d, struct mpam_resctrl_dom,
+					resctrl_dom);
+			mpam_reset_cfg(res, dom, d);
+		}
+	}
+
+	mpam_reset_devices();
+
+	/*
+	 * reset CDP configuration used in recreating schema list nodes.
+	 */
+	resctrl_cdp_enabled = false;
+}
+
 u16 mpam_resctrl_max_mon_num(void)
 {
 	struct mpam_resctrl_res *res;