s390/pgalloc: use pointers instead of unsigned long values

After adding the missing __va()/__pa() calls to the base asce
functions there are even more casts in the code than before. Make the
code more readable by passing and using pointers to page tables,
instead of using unsigned values for the same purpose.

This allows to get rid of nearly all casts within the code.
Suggested-by: Alexander Gordeev <agordeev@linux.ibm.com>
Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>

arch/s390/mm/pgalloc.c

@@ -322,34 +322,34 @@ void __tlb_remove_table(void *_table)
 
 static struct kmem_cache *base_pgt_cache;
 
-static unsigned long base_pgt_alloc(void)
+static unsigned long *base_pgt_alloc(void)
 {
-	u64 *table;
+	unsigned long *table;
 
 	table = kmem_cache_alloc(base_pgt_cache, GFP_KERNEL);
 	if (table)
-		memset64(table, _PAGE_INVALID, PTRS_PER_PTE);
-	return (unsigned long) table;
+		memset64((u64 *)table, _PAGE_INVALID, PTRS_PER_PTE);
+	return table;
 }
 
-static void base_pgt_free(unsigned long table)
+static void base_pgt_free(unsigned long *table)
 {
-	kmem_cache_free(base_pgt_cache, (void *) table);
+	kmem_cache_free(base_pgt_cache, table);
 }
 
-static unsigned long base_crst_alloc(unsigned long val)
+static unsigned long *base_crst_alloc(unsigned long val)
 {
-	unsigned long table;
+	unsigned long *table;
 
-	table =	 __get_free_pages(GFP_KERNEL, CRST_ALLOC_ORDER);
+	table =	(unsigned long *)__get_free_pages(GFP_KERNEL, CRST_ALLOC_ORDER);
 	if (table)
-		crst_table_init((unsigned long *)table, val);
+		crst_table_init(table, val);
 	return table;
 }
 
-static void base_crst_free(unsigned long table)
+static void base_crst_free(unsigned long *table)
 {
-	free_pages(table, CRST_ALLOC_ORDER);
+	free_pages((unsigned long)table, CRST_ALLOC_ORDER);
 }
 
 #define BASE_ADDR_END_FUNC(NAME, SIZE)					\
@@ -377,14 +377,14 @@ static inline unsigned long base_lra(unsigned long address)
 	return real;
 }
 
-static int base_page_walk(unsigned long origin, unsigned long addr,
+static int base_page_walk(unsigned long *origin, unsigned long addr,
 			  unsigned long end, int alloc)
 {
 	unsigned long *pte, next;
 
 	if (!alloc)
 		return 0;
-	pte = (unsigned long *) origin;
+	pte = origin;
 	pte += (addr & _PAGE_INDEX) >> _PAGE_SHIFT;
 	do {
 		next = base_page_addr_end(addr, end);
@@ -393,13 +393,13 @@ static int base_page_walk(unsigned long origin, unsigned long addr,
 	return 0;
 }
 
-static int base_segment_walk(unsigned long origin, unsigned long addr,
+static int base_segment_walk(unsigned long *origin, unsigned long addr,
 			     unsigned long end, int alloc)
 {
-	unsigned long *ste, next, table;
+	unsigned long *ste, next, *table;
 	int rc;
 
-	ste = (unsigned long *) origin;
+	ste = origin;
 	ste += (addr & _SEGMENT_INDEX) >> _SEGMENT_SHIFT;
 	do {
 		next = base_segment_addr_end(addr, end);
@@ -411,7 +411,7 @@ static int base_segment_walk(unsigned long origin, unsigned long addr,
 				return -ENOMEM;
 			*ste = __pa(table) | _SEGMENT_ENTRY;
 		}
-		table = (unsigned long)__va(*ste & _SEGMENT_ENTRY_ORIGIN);
+		table = __va(*ste & _SEGMENT_ENTRY_ORIGIN);
 		rc = base_page_walk(table, addr, next, alloc);
 		if (rc)
 			return rc;
@@ -422,13 +422,13 @@ static int base_segment_walk(unsigned long origin, unsigned long addr,
 	return 0;
 }
 
-static int base_region3_walk(unsigned long origin, unsigned long addr,
+static int base_region3_walk(unsigned long *origin, unsigned long addr,
 			     unsigned long end, int alloc)
 {
-	unsigned long *rtte, next, table;
+	unsigned long *rtte, next, *table;
 	int rc;
 
-	rtte = (unsigned long *) origin;
+	rtte = origin;
 	rtte += (addr & _REGION3_INDEX) >> _REGION3_SHIFT;
 	do {
 		next = base_region3_addr_end(addr, end);
@@ -440,7 +440,7 @@ static int base_region3_walk(unsigned long origin, unsigned long addr,
 				return -ENOMEM;
 			*rtte = __pa(table) | _REGION3_ENTRY;
 		}
-		table = (unsigned long)__va(*rtte & _REGION_ENTRY_ORIGIN);
+		table = __va(*rtte & _REGION_ENTRY_ORIGIN);
 		rc = base_segment_walk(table, addr, next, alloc);
 		if (rc)
 			return rc;
@@ -450,13 +450,13 @@ static int base_region3_walk(unsigned long origin, unsigned long addr,
 	return 0;
 }
 
-static int base_region2_walk(unsigned long origin, unsigned long addr,
+static int base_region2_walk(unsigned long *origin, unsigned long addr,
 			     unsigned long end, int alloc)
 {
-	unsigned long *rste, next, table;
+	unsigned long *rste, next, *table;
 	int rc;
 
-	rste = (unsigned long *) origin;
+	rste = origin;
 	rste += (addr & _REGION2_INDEX) >> _REGION2_SHIFT;
 	do {
 		next = base_region2_addr_end(addr, end);
@@ -468,7 +468,7 @@ static int base_region2_walk(unsigned long origin, unsigned long addr,
 				return -ENOMEM;
 			*rste = __pa(table) | _REGION2_ENTRY;
 		}
-		table = (unsigned long)__va(*rste & _REGION_ENTRY_ORIGIN);
+		table = __va(*rste & _REGION_ENTRY_ORIGIN);
 		rc = base_region3_walk(table, addr, next, alloc);
 		if (rc)
 			return rc;
@@ -478,13 +478,13 @@ static int base_region2_walk(unsigned long origin, unsigned long addr,
 	return 0;
 }
 
-static int base_region1_walk(unsigned long origin, unsigned long addr,
+static int base_region1_walk(unsigned long *origin, unsigned long addr,
 			     unsigned long end, int alloc)
 {
-	unsigned long *rfte, next, table;
+	unsigned long *rfte, next, *table;
 	int rc;
 
-	rfte = (unsigned long *) origin;
+	rfte = origin;
 	rfte += (addr & _REGION1_INDEX) >> _REGION1_SHIFT;
 	do {
 		next = base_region1_addr_end(addr, end);
@@ -496,7 +496,7 @@ static int base_region1_walk(unsigned long origin, unsigned long addr,
 				return -ENOMEM;
 			*rfte = __pa(table) | _REGION1_ENTRY;
 		}
-		table = (unsigned long)__va(*rfte & _REGION_ENTRY_ORIGIN);
+		table = __va(*rfte & _REGION_ENTRY_ORIGIN);
 		rc = base_region2_walk(table, addr, next, alloc);
 		if (rc)
 			return rc;
@@ -515,7 +515,7 @@ static int base_region1_walk(unsigned long origin, unsigned long addr,
  */
 void base_asce_free(unsigned long asce)
 {
-	unsigned long table = (unsigned long)__va(asce & _ASCE_ORIGIN);
+	unsigned long *table = __va(asce & _ASCE_ORIGIN);
 
 	if (!asce)
 		return;
@@ -567,7 +567,7 @@ static int base_pgt_cache_init(void)
  */
 unsigned long base_asce_alloc(unsigned long addr, unsigned long num_pages)
 {
-	unsigned long asce, table, end;
+	unsigned long asce, *table, end;
 	int rc;
 
 	if (base_pgt_cache_init())