kernel/res_counter.c: replace simple_strtoull by kstrtoull

[akpm@linux-foundation.org: don't overwrite kstrtoull()'s errno]
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Author: Fabian Frederick

kernel/res_counter.c

@@ -186,8 +186,11 @@ int res_counter_memparse_write_strategy(const char *buf,
 
 	/* return RES_COUNTER_MAX(unlimited) if "-1" is specified */
 	if (*buf == '-') {
-		res = simple_strtoull(buf + 1, &end, 10);
-		if (res != 1 || *end != '\0')
+		int rc = kstrtoull(buf + 1, 10, &res);
+
+		if (rc)
+			return rc;
+		if (res != 1)
 			return -EINVAL;
 		*resp = RES_COUNTER_MAX;
 		return 0;