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-rw-r--r--arch/s390/include/asm/bitops.h31
-rw-r--r--arch/s390/lib/find.c4
2 files changed, 13 insertions, 22 deletions
diff --git a/arch/s390/include/asm/bitops.h b/arch/s390/include/asm/bitops.h
index 47bd0878a006..8043f10da6b5 100644
--- a/arch/s390/include/asm/bitops.h
+++ b/arch/s390/include/asm/bitops.h
@@ -11,30 +11,25 @@
* big-endian system because, unlike little endian, the number of each
* bit depends on the word size.
*
- * The bitop functions are defined to work on unsigned longs, so for an
- * s390x system the bits end up numbered:
+ * The bitop functions are defined to work on unsigned longs, so the bits
+ * end up numbered:
* |63..............0|127............64|191...........128|255...........192|
- * and on s390:
- * |31.....0|63....32|95....64|127...96|159..128|191..160|223..192|255..224|
*
* There are a few little-endian macros used mostly for filesystem
- * bitmaps, these work on similar bit arrays layouts, but
- * byte-oriented:
+ * bitmaps, these work on similar bit array layouts, but byte-oriented:
* |7...0|15...8|23...16|31...24|39...32|47...40|55...48|63...56|
*
- * The main difference is that bit 3-5 (64b) or 3-4 (32b) in the bit
- * number field needs to be reversed compared to the big-endian bit
- * fields. This can be achieved by XOR with 0x38 (64b) or 0x18 (32b).
+ * The main difference is that bit 3-5 in the bit number field needs to be
+ * reversed compared to the big-endian bit fields. This can be achieved by
+ * XOR with 0x38.
*
- * We also have special functions which work with an MSB0 encoding:
- * on an s390x system the bits are numbered:
+ * We also have special functions which work with an MSB0 encoding.
+ * The bits are numbered:
* |0..............63|64............127|128...........191|192...........255|
- * and on s390:
- * |0.....31|32....63|64....95|96...127|128..159|160..191|192..223|224..255|
*
- * The main difference is that bit 0-63 (64b) or 0-31 (32b) in the bit
- * number field needs to be reversed compared to the LSB0 encoded bit
- * fields. This can be achieved by XOR with 0x3f (64b) or 0x1f (32b).
+ * The main difference is that bit 0-63 in the bit number field needs to be
+ * reversed compared to the LSB0 encoded bit fields. This can be achieved by
+ * XOR with 0x3f.
*
*/
@@ -299,10 +294,8 @@ static inline void __clear_bit_unlock(unsigned long nr,
/*
* Functions which use MSB0 bit numbering.
- * On an s390x system the bits are numbered:
+ * The bits are numbered:
* |0..............63|64............127|128...........191|192...........255|
- * and on s390:
- * |0.....31|32....63|64....95|96...127|128..159|160..191|192..223|224..255|
*/
unsigned long find_first_bit_inv(const unsigned long *addr, unsigned long size);
unsigned long find_next_bit_inv(const unsigned long *addr, unsigned long size,
diff --git a/arch/s390/lib/find.c b/arch/s390/lib/find.c
index 922003c1b90d..d90b9245ea41 100644
--- a/arch/s390/lib/find.c
+++ b/arch/s390/lib/find.c
@@ -1,10 +1,8 @@
/*
* MSB0 numbered special bitops handling.
*
- * On s390x the bits are numbered:
+ * The bits are numbered:
* |0..............63|64............127|128...........191|192...........255|
- * and on s390:
- * |0.....31|32....63|64....95|96...127|128..159|160..191|192..223|224..255|
*
* The reason for this bit numbering is the fact that the hardware sets bits
* in a bitmap starting at bit 0 (MSB) and we don't want to scan the bitmap