mtd: partitions: remove kmemdup()

The use of kmemdup() complicates the error handling a bit. We don't
actually need to allocate new memory, since this reference is treated as
const, and it is copied into new memory by the partition registration
code anyway. So remove it.
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Reviewed-by: Boris Brezillon <boris.brezillon@free-electrons.com>

drivers/mtd/mtdcore.c

@@ -532,7 +532,7 @@ int del_mtd_device(struct mtd_info *mtd)
 }
 
 static int mtd_add_device_partitions(struct mtd_info *mtd,
-				     struct mtd_partition *real_parts,
+				     const struct mtd_partition *real_parts,
 				     int nbparts)
 {
 	int ret;
@@ -589,16 +589,12 @@ int mtd_device_parse_register(struct mtd_info *mtd, const char * const *types,
 			      int nr_parts)
 {
 	int ret;
-	struct mtd_partition *real_parts = NULL;
+	const struct mtd_partition *real_parts = NULL;
 
 	ret = parse_mtd_partitions(mtd, types, &real_parts, parser_data);
 	if (ret <= 0 && nr_parts && parts) {
-		real_parts = kmemdup(parts, sizeof(*parts) * nr_parts,
-				     GFP_KERNEL);
-		if (!real_parts)
-			ret = -ENOMEM;
-		else
-			ret = nr_parts;
+		real_parts = parts;
+		ret = nr_parts;
 	}
 	/* Didn't come up with either parsed OR fallback partitions */
 	if (ret < 0) {
@@ -628,7 +624,9 @@ int mtd_device_parse_register(struct mtd_info *mtd, const char * const *types,
 	}
 
 out:
-	kfree(real_parts);
+	/* Cleanup any parsed partitions */
+	if (real_parts != parts)
+		kfree(real_parts);
 	return ret;
 }
 EXPORT_SYMBOL_GPL(mtd_device_parse_register);

drivers/mtd/mtdcore.h

@@ -11,7 +11,7 @@ int del_mtd_device(struct mtd_info *mtd);
 int add_mtd_partitions(struct mtd_info *, const struct mtd_partition *, int);
 int del_mtd_partitions(struct mtd_info *);
 int parse_mtd_partitions(struct mtd_info *master, const char * const *types,
-			 struct mtd_partition **pparts,
+			 const struct mtd_partition **pparts,
 			 struct mtd_part_parser_data *data);
 
 int __init init_mtdchar(void);

drivers/mtd/mtdpart.c

@@ -760,7 +760,7 @@ static const char * const default_mtd_part_types[] = {
  *   point to an array containing this number of &struct mtd_info objects.
  */
 int parse_mtd_partitions(struct mtd_info *master, const char *const *types,
-			 struct mtd_partition **pparts,
+			 const struct mtd_partition **pparts,
 			 struct mtd_part_parser_data *data)
 {
 	struct mtd_part_parser *parser;