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-rw-r--r--fs/minix/bitmap.c41
-rw-r--r--fs/minix/minix.h2
2 files changed, 15 insertions, 28 deletions
diff --git a/fs/minix/bitmap.c b/fs/minix/bitmap.c
index 7c82c29429d7..ef175cb8cfd8 100644
--- a/fs/minix/bitmap.c
+++ b/fs/minix/bitmap.c
@@ -16,39 +16,26 @@
16#include <linux/bitops.h> 16#include <linux/bitops.h>
17#include <linux/sched.h> 17#include <linux/sched.h>
18 18
19static const int nibblemap[] = { 4,3,3,2,3,2,2,1,3,2,2,1,2,1,1,0 };
20
21static DEFINE_SPINLOCK(bitmap_lock); 19static DEFINE_SPINLOCK(bitmap_lock);
22 20
23static unsigned long count_free(struct buffer_head *map[], unsigned blocksize, __u32 numbits) 21/*
22 * bitmap consists of blocks filled with 16bit words
23 * bit set == busy, bit clear == free
24 * endianness is a mess, but for counting zero bits it really doesn't matter...
25 */
26static __u32 count_free(struct buffer_head *map[], unsigned blocksize, __u32 numbits)
24{ 27{
25 unsigned i, j, sum = 0; 28 __u32 sum = 0;
26 struct buffer_head *bh; 29 unsigned blocks = DIV_ROUND_UP(numbits, blocksize * 8);
27 unsigned numblocks = minix_blocks_needed(numbits, blocksize);
28
29 for (i=0; i<numblocks-1; i++) {
30 if (!(bh=map[i]))
31 return(0);
32 for (j=0; j<bh->b_size; j++)
33 sum += nibblemap[bh->b_data[j] & 0xf]
34 + nibblemap[(bh->b_data[j]>>4) & 0xf];
35 }
36 30
37 if (numblocks==0 || !(bh=map[numblocks-1])) 31 while (blocks--) {
38 return(0); 32 unsigned words = blocksize / 2;
39 i = ((numbits - (numblocks-1) * bh->b_size * 8) / 16) * 2; 33 __u16 *p = (__u16 *)(*map++)->b_data;
40 for (j=0; j<i; j++) { 34 while (words--)
41 sum += nibblemap[bh->b_data[j] & 0xf] 35 sum += 16 - hweight16(*p++);
42 + nibblemap[(bh->b_data[j]>>4) & 0xf];
43 } 36 }
44 37
45 i = numbits%16; 38 return sum;
46 if (i!=0) {
47 i = *(__u16 *)(&bh->b_data[j]) | ~((1<<i) - 1);
48 sum += nibblemap[i & 0xf] + nibblemap[(i>>4) & 0xf];
49 sum += nibblemap[(i>>8) & 0xf] + nibblemap[(i>>12) & 0xf];
50 }
51 return(sum);
52} 39}
53 40
54void minix_free_block(struct inode *inode, unsigned long block) 41void minix_free_block(struct inode *inode, unsigned long block)
diff --git a/fs/minix/minix.h b/fs/minix/minix.h
index 6415fe0d2385..26bbd55e82ea 100644
--- a/fs/minix/minix.h
+++ b/fs/minix/minix.h
@@ -130,7 +130,7 @@ static inline int minix_find_first_zero_bit(const void *vaddr, unsigned size)
130 if (!size) 130 if (!size)
131 return 0; 131 return 0;
132 132
133 size = (size >> 4) + ((size & 15) > 0); 133 size >>= 4;
134 while (*p++ == 0xffff) { 134 while (*p++ == 0xffff) {
135 if (--size == 0) 135 if (--size == 0)
136 return (p - addr) << 4; 136 return (p - addr) << 4;