mm/sharepool: Configure the DVPP range for process

hulk inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I5DS9S
CVE: NA

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

Currently the dvpp range is global for each device. And it is
unreasonable after the reconstruction that makes the DVPP mappings
private to each process or group.

This allows to configure the dvpp range for each process.
The dvpp range for each dvpp mapping can only be configured once just
as the old version.
Signed-off-by: NWang Wensheng <wangwensheng4@huawei.com>
Reviewed-by: NWeilong Chen <chenweilong@huawei.com>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>

mm/share_pool.c

@@ -220,6 +220,17 @@ static bool is_mapping_empty(struct sp_mapping *spm)
 	return RB_EMPTY_ROOT(&spm->area_root);
 }
 
+static bool can_mappings_merge(struct sp_mapping *m1, struct sp_mapping *m2)
+{
+	int i;
+
+	for (i = 0; i < sp_device_number; i++)
+		if (m1->start[i] != m2->start[i] || m1->end[i] != m2->end[i])
+			return false;
+
+	return true;
+}
+
 /*
  * 1. The mappings of local group is set on creating.
  * 2. This is used to setup the mapping for groups created during add_task.
@@ -235,6 +246,11 @@ static int sp_mapping_group_setup(struct mm_struct *mm, struct sp_group *spg)
 	struct sp_group *local = master->local;
 
 	if (!list_empty(&spg->procs) && !(spg->flag & SPG_FLAG_NON_DVPP)) {
+		if (!can_mappings_merge(local->dvpp, spg->dvpp)) {
+			pr_info_ratelimited("address space conflict, id=%d\n", spg->id);
+			return -EINVAL;
+		}
+
 		if (is_mapping_empty(local->dvpp))
 			sp_mapping_merge(spg->dvpp, local->dvpp);
 		else if (is_mapping_empty(spg->dvpp))
@@ -3825,16 +3841,50 @@ EXPORT_SYMBOL_GPL(sp_unregister_notifier);
  */
 bool sp_config_dvpp_range(size_t start, size_t size, int device_id, int pid)
 {
-	if (pid < 0 ||
-	    size <= 0 || size > MMAP_SHARE_POOL_16G_SIZE ||
-	    device_id < 0 || device_id >= sp_device_number ||
-	    !is_online_node_id(device_id) ||
-	    is_sp_dev_addr_enabled(device_id))
+	int ret;
+	bool err = false;
+	struct task_struct *tsk;
+	struct mm_struct *mm;
+	struct sp_group *spg;
+	struct sp_mapping *spm;
+	unsigned long default_start;
+
+	/* NOTE: check the start address */
+	if (pid < 0 || size <= 0 || size > MMAP_SHARE_POOL_16G_SIZE ||
+	    device_id < 0 || device_id >= sp_device_number || !is_online_node_id(device_id))
 		return false;
 
-	sp_dev_va_start[device_id] = start;
-	sp_dev_va_size[device_id] = size;
-	return true;
+	ret = get_task(pid, &tsk);
+	if (ret)
+		return false;
+
+	mm = get_task_mm(tsk->group_leader);
+	if (!mm)
+		goto put_task;
+
+	spg = sp_get_local_group(mm);
+	if (IS_ERR(spg))
+		goto put_mm;
+
+	spm = spg->dvpp;
+	default_start = MMAP_SHARE_POOL_16G_START + device_id * MMAP_SHARE_POOL_16G_SIZE;
+	/* The dvpp range of each group can be configured only once */
+	if (spm->start[device_id] != default_start)
+		goto put_spg;
+
+	spm->start[device_id] = start;
+	spm->end[device_id] = start + size;
+
+	err = true;
+
+put_spg:
+	sp_group_drop(spg);
+put_mm:
+	mmput(mm);
+put_task:
+	put_task_struct(tsk);
+
+	return err;
 }
 EXPORT_SYMBOL_GPL(sp_config_dvpp_range);