Update Linux to v5.4.2
Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/arch/s390/boot/string.c b/arch/s390/boot/string.c
new file mode 100644
index 0000000..b11e810
--- /dev/null
+++ b/arch/s390/boot/string.c
@@ -0,0 +1,139 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/ctype.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#undef CONFIG_KASAN
+#include "../lib/string.c"
+
+int strncmp(const char *cs, const char *ct, size_t count)
+{
+ unsigned char c1, c2;
+
+ while (count) {
+ c1 = *cs++;
+ c2 = *ct++;
+ if (c1 != c2)
+ return c1 < c2 ? -1 : 1;
+ if (!c1)
+ break;
+ count--;
+ }
+ return 0;
+}
+
+char *skip_spaces(const char *str)
+{
+ while (isspace(*str))
+ ++str;
+ return (char *)str;
+}
+
+char *strim(char *s)
+{
+ size_t size;
+ char *end;
+
+ size = strlen(s);
+ if (!size)
+ return s;
+
+ end = s + size - 1;
+ while (end >= s && isspace(*end))
+ end--;
+ *(end + 1) = '\0';
+
+ return skip_spaces(s);
+}
+
+/* Works only for digits and letters, but small and fast */
+#define TOLOWER(x) ((x) | 0x20)
+
+static unsigned int simple_guess_base(const char *cp)
+{
+ if (cp[0] == '0') {
+ if (TOLOWER(cp[1]) == 'x' && isxdigit(cp[2]))
+ return 16;
+ else
+ return 8;
+ } else {
+ return 10;
+ }
+}
+
+/**
+ * simple_strtoull - convert a string to an unsigned long long
+ * @cp: The start of the string
+ * @endp: A pointer to the end of the parsed string will be placed here
+ * @base: The number base to use
+ */
+
+unsigned long long simple_strtoull(const char *cp, char **endp,
+ unsigned int base)
+{
+ unsigned long long result = 0;
+
+ if (!base)
+ base = simple_guess_base(cp);
+
+ if (base == 16 && cp[0] == '0' && TOLOWER(cp[1]) == 'x')
+ cp += 2;
+
+ while (isxdigit(*cp)) {
+ unsigned int value;
+
+ value = isdigit(*cp) ? *cp - '0' : TOLOWER(*cp) - 'a' + 10;
+ if (value >= base)
+ break;
+ result = result * base + value;
+ cp++;
+ }
+ if (endp)
+ *endp = (char *)cp;
+
+ return result;
+}
+
+long simple_strtol(const char *cp, char **endp, unsigned int base)
+{
+ if (*cp == '-')
+ return -simple_strtoull(cp + 1, endp, base);
+
+ return simple_strtoull(cp, endp, base);
+}
+
+int kstrtobool(const char *s, bool *res)
+{
+ if (!s)
+ return -EINVAL;
+
+ switch (s[0]) {
+ case 'y':
+ case 'Y':
+ case '1':
+ *res = true;
+ return 0;
+ case 'n':
+ case 'N':
+ case '0':
+ *res = false;
+ return 0;
+ case 'o':
+ case 'O':
+ switch (s[1]) {
+ case 'n':
+ case 'N':
+ *res = true;
+ return 0;
+ case 'f':
+ case 'F':
+ *res = false;
+ return 0;
+ default:
+ break;
+ }
+ default:
+ break;
+ }
+
+ return -EINVAL;
+}