Commit 9b58f6d4 authored by Akinobu Mita's avatar Akinobu Mita Committed by Linus Torvalds
Browse files

qnx4fs: use memweight()

Use memweight() to count the total number of bits clear in memory area.

Note that this memweight() call can't be replaced with a single
bitmap_weight() call, although the pointer to the memory area is aligned
to long-word boundary.  Because the size of the memory area may not be a
multiple of BITS_PER_LONG, then it returns wrong value on big-endian
Signed-off-by: default avatarAkinobu Mita <>
Acked-by: default avatarAnders Larsen <>
Signed-off-by: default avatarAndrew Morton <>
Signed-off-by: default avatarLinus Torvalds <>
parent 639b9e34
......@@ -17,23 +17,6 @@
#include <linux/bitops.h>
#include "qnx4.h"
static void count_bits(register const char *bmPart, register int size,
int *const tf)
char b;
int tot = *tf;
if (size > QNX4_BLOCK_SIZE) {
do {
b = *bmPart++;
tot += 8 - hweight8(b);
} while (size != 0);
*tf = tot;
unsigned long qnx4_count_free_blocks(struct super_block *sb)
int start = le32_to_cpu(qnx4_sb(sb)->BitMap->di_first_xtnt.xtnt_blk) - 1;
......@@ -44,13 +27,16 @@ unsigned long qnx4_count_free_blocks(struct super_block *sb)
struct buffer_head *bh;
while (total < size) {
int bytes = min(size - total, QNX4_BLOCK_SIZE);
if ((bh = sb_bread(sb, start + offset)) == NULL) {
printk(KERN_ERR "qnx4: I/O error in counting free blocks\n");
count_bits(bh->b_data, size - total, &total_free);
total_free += bytes * BITS_PER_BYTE -
memweight(bh->b_data, bytes);
total += QNX4_BLOCK_SIZE;
total += bytes;
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