mm: Reserve field in mm_struct for memory reliable

hulk inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I4SK3S
DTS: #896
CVE: NA

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Reserved a variable in mm_struct while will be used by memory reliable.
Signed-off-by: NPeng Wu <wupeng58@huawei.com>
Reviewed-by: NKefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>

include/linux/mm_types.h

@@ -585,6 +585,10 @@ struct mm_struct {
 #ifdef CONFIG_IOMMU_SUPPORT
 		u32 pasid;
 #endif
+
+#ifdef CONFIG_MEMORY_RELIABLE
+		atomic_long_t reserve_0;
+#endif
 	} __randomize_layout;
 
 	KABI_RESERVE(1)