procfs: consolidate arch_report_meminfo declaration

The arch_report_meminfo() function is provided by four architectures,
with a __weak fallback in procfs itself. On architectures that don't
have a custom version, the __weak version causes a warning because
of the missing prototype.

Remove the architecture specific prototypes and instead add one
in linux/proc_fs.h.

Signed-off-by: Arnd Bergmann <[e-mail]>
Acked-by: Dave Hansen <[e-mail]> # for arch/x86
Acked-by: Helge Deller <[e-mail]> # parisc
Reviewed-by: Alexander Gordeev <[e-mail]>
Message-Id: <[e-mail]>
Signed-off-by: Christian Brauner <[e-mail]>

arch/parisc/include/asm/pgtable.h

···
 
 #define pte_same(A,B)	(pte_val(A) == pte_val(B))
 
-struct seq_file;
-extern void arch_report_meminfo(struct seq_file *m);
-
 #endif /* !__ASSEMBLY__ */
 
 

arch/powerpc/include/asm/pgtable.h

···
 
 	return addr >= IOREMAP_BASE && addr < IOREMAP_END;
 }
-
-struct seq_file;
-void arch_report_meminfo(struct seq_file *m);
 #endif /* CONFIG_PPC64 */
 
 #endif /* __ASSEMBLY__ */

arch/s390/include/asm/pgtable.h

···
 		atomic_long_add(count, &direct_pages_count[level]);
 }
 
-struct seq_file;
-void arch_report_meminfo(struct seq_file *m);
-
 /*
  * The S390 doesn't have any external MMU info: the kernel page
  * tables contain all the necessary information.

arch/s390/mm/pageattr.c

···
  * Author(s): Jan Glauber <[e-mail]>
  */
 #include <linux/hugetlb.h>
+#include <linux/proc_fs.h>
 #include <linux/vmalloc.h>
 #include <linux/mm.h>
 #include <asm/cacheflush.h>

arch/x86/include/asm/pgtable.h

···
 extern pgd_t early_top_pgt[PTRS_PER_PGD];
 bool __init __early_make_pgtable(unsigned long address, pmdval_t pmd);
 
+struct seq_file;
 void ptdump_walk_pgd_level(struct seq_file *m, struct mm_struct *mm);
 void ptdump_walk_pgd_level_debugfs(struct seq_file *m, struct mm_struct *mm,
 				   bool user);

arch/x86/include/asm/pgtable_types.h

···
 #define native_pagetable_init        paging_init
 #endif
 
-struct seq_file;
-extern void arch_report_meminfo(struct seq_file *m);
-
 enum pg_level {
 	PG_LEVEL_NONE,
 	PG_LEVEL_4K,

arch/x86/mm/pat/set_memory.c

···
 #include <linux/mm.h>
 #include <linux/interrupt.h>
 #include <linux/seq_file.h>
+#include <linux/proc_fs.h>
 #include <linux/debugfs.h>
 #include <linux/pfn.h>
 #include <linux/percpu.h>

include/linux/proc_fs.h

···
 			struct pid *pid, struct task_struct *task);
 #endif /* CONFIG_PROC_PID_ARCH_STATUS */
 
+void arch_report_meminfo(struct seq_file *m);
+
 #else /* CONFIG_PROC_FS */
 
 static inline void proc_root_init(void)