s390/ebcdic: Fix length check in codepage_convert()

svens-s390 · Alexander Gordeev · commit 4a0f62a3009b · 2025-01-13T09:50:18.000+01:00
The current code compares whether the nr argument is less or equal to
zero. As nr is of type unsigned long, this isn't correct. Fix this by just
testing for zero. This is also reported by checkpatch:

unsignedLessThanZero: Checking if unsigned expression 'nr--' is less
than zero.

Reported-by: Jens Remus &lt;jremus@linux.ibm.com&gt;
Signed-off-by: Sven Schnelle &lt;svens@linux.ibm.com&gt;
Reviewed-by: Heiko Carstens &lt;hca@linux.ibm.com&gt;
Signed-off-by: Alexander Gordeev &lt;agordeev@linux.ibm.com&gt;
diff --git a/arch/s390/include/asm/ebcdic.h b/arch/s390/include/asm/ebcdic.h
@@ -22,7 +22,7 @@ extern __u8 _ebc_toupper[256]; /* EBCDIC -> uppercase */
 static inline void
 codepage_convert(const __u8 *codepage, volatile char *addr, unsigned long nr)
 {
-	if (nr-- <= 0)
+	if (!nr--)
 		return;
 	asm volatile(
 		"	j	2f\n"

Original file line number	Diff line number	Diff line change
`@@ -22,7 +22,7 @@ extern __u8 _ebc_toupper[256]; /* EBCDIC -> uppercase */`
`22`	`22`	`static inline void`
`23`	`23`	`codepage_convert(const __u8 codepage, volatile char addr, unsigned long nr)`
`24`	`24`	`{`
`25`		`- if (nr-- <= 0)`
	`25`	`+ if (!nr--)`
`26`	`26`	`return;`
`27`	`27`	`asm volatile(`
`28`	`28`	`" j 2f\n"`