kmap: remove kmap_atomic_to_page()

kmap_atomic_to_page() has no callers and is only defined on 1 arch and
declared on another. Remove it.

Suggested-by: Al Viro <[e-mail]>
Signed-off-by: Ira Weiny <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
Cc: Andy Lutomirski <[e-mail]>
Cc: Benjamin Herrenschmidt <[e-mail]>
Cc: Borislav Petkov <[e-mail]>
Cc: Christian König <[e-mail]>
Cc: Christoph Hellwig <[e-mail]>
Cc: Chris Zankel <[e-mail]>
Cc: Daniel Vetter <[e-mail]>
Cc: Dan Williams <[e-mail]>
Cc: Dave Hansen <[e-mail]>
Cc: "David S. Miller" <[e-mail]>
Cc: Helge Deller <[e-mail]>
Cc: "H. Peter Anvin" <[e-mail]>
Cc: Ingo Molnar <[e-mail]>
Cc: "James E.J. Bottomley" <[e-mail]>
Cc: Max Filippov <[e-mail]>
Cc: Paul Mackerras <[e-mail]>
Cc: Peter Zijlstra <[e-mail]>
Cc: Thomas Bogendoerfer <[e-mail]>
Cc: Thomas Gleixner <[e-mail]>
Link: http://lkml.kernel.org/r/[e-mail]
Signed-off-by: Linus Torvalds <[e-mail]>

arch/csky/include/asm/highmem.h

···
 #define ARCH_HAS_KMAP_FLUSH_TLB
 extern void kmap_flush_tlb(unsigned long addr);
 extern void *kmap_atomic_pfn(unsigned long pfn);
-extern struct page *kmap_atomic_to_page(void *ptr);
 
 #define flush_cache_kmaps() do {} while (0)
 

arch/csky/mm/highmem.c

···
 	return (void *) vaddr;
 }
 
-struct page *kmap_atomic_to_page(void *ptr)
-{
-	unsigned long idx, vaddr = (unsigned long)ptr;
-	pte_t *pte;
-
-	if (vaddr < FIXADDR_START)
-		return virt_to_page(ptr);
-
-	idx = virt_to_fix(vaddr);
-	pte = kmap_pte - (idx - FIX_KMAP_BEGIN);
-	return pte_page(*pte);
-}
-
 static void __init kmap_pages_init(void)
 {
 	unsigned long vaddr;

arch/nds32/include/asm/highmem.h

···
  */
 #ifdef CONFIG_HIGHMEM
 extern void *kmap_atomic_pfn(unsigned long pfn);
-extern struct page *kmap_atomic_to_page(void *ptr);
 #endif
 
 #endif