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-rw-r--r--fs/exfat/balloc.c87
1 files changed, 35 insertions, 52 deletions
diff --git a/fs/exfat/balloc.c b/fs/exfat/balloc.c
index e918decb37..0356c88252 100644
--- a/fs/exfat/balloc.c
+++ b/fs/exfat/balloc.c
@@ -5,42 +5,23 @@
#include <linux/blkdev.h>
#include <linux/slab.h>
+#include <linux/bitmap.h>
#include <linux/buffer_head.h>
#include "exfat_raw.h"
#include "exfat_fs.h"
-static const unsigned char free_bit[] = {
- 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0, 4, 0, 1, 0, 2,/* 0 ~ 19*/
- 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0, 5, 0, 1, 0, 2, 0, 1, 0, 3,/* 20 ~ 39*/
- 0, 1, 0, 2, 0, 1, 0, 4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2,/* 40 ~ 59*/
- 0, 1, 0, 6, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0, 4,/* 60 ~ 79*/
- 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0, 5, 0, 1, 0, 2,/* 80 ~ 99*/
- 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0, 4, 0, 1, 0, 2, 0, 1, 0, 3,/*100 ~ 119*/
- 0, 1, 0, 2, 0, 1, 0, 7, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2,/*120 ~ 139*/
- 0, 1, 0, 4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0, 5,/*140 ~ 159*/
- 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0, 4, 0, 1, 0, 2,/*160 ~ 179*/
- 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0, 6, 0, 1, 0, 2, 0, 1, 0, 3,/*180 ~ 199*/
- 0, 1, 0, 2, 0, 1, 0, 4, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2,/*200 ~ 219*/
- 0, 1, 0, 5, 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0, 4,/*220 ~ 239*/
- 0, 1, 0, 2, 0, 1, 0, 3, 0, 1, 0, 2, 0, 1, 0 /*240 ~ 254*/
-};
-
-static const unsigned char used_bit[] = {
- 0, 1, 1, 2, 1, 2, 2, 3, 1, 2, 2, 3, 2, 3, 3, 4, 1, 2, 2, 3,/* 0 ~ 19*/
- 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5, 1, 2, 2, 3, 2, 3, 3, 4,/* 20 ~ 39*/
- 2, 3, 3, 4, 3, 4, 4, 5, 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5,/* 40 ~ 59*/
- 4, 5, 5, 6, 1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5,/* 60 ~ 79*/
- 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6, 2, 3, 3, 4,/* 80 ~ 99*/
- 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6, 3, 4, 4, 5, 4, 5, 5, 6,/*100 ~ 119*/
- 4, 5, 5, 6, 5, 6, 6, 7, 1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4,/*120 ~ 139*/
- 3, 4, 4, 5, 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,/*140 ~ 159*/
- 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6, 3, 4, 4, 5,/*160 ~ 179*/
- 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7, 2, 3, 3, 4, 3, 4, 4, 5,/*180 ~ 199*/
- 3, 4, 4, 5, 4, 5, 5, 6, 3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6,/*200 ~ 219*/
- 5, 6, 6, 7, 3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7,/*220 ~ 239*/
- 4, 5, 5, 6, 5, 6, 6, 7, 5, 6, 6, 7, 6, 7, 7, 8 /*240 ~ 255*/
-};
+#if BITS_PER_LONG == 32
+#define __le_long __le32
+#define lel_to_cpu(A) le32_to_cpu(A)
+#define cpu_to_lel(A) cpu_to_le32(A)
+#elif BITS_PER_LONG == 64
+#define __le_long __le64
+#define lel_to_cpu(A) le64_to_cpu(A)
+#define cpu_to_lel(A) cpu_to_le64(A)
+#else
+#error "BITS_PER_LONG not 32 or 64"
+#endif
/*
* Allocation Bitmap Management Functions
@@ -200,32 +181,35 @@ unsigned int exfat_find_free_bitmap(struct super_block *sb, unsigned int clu)
{
unsigned int i, map_i, map_b, ent_idx;
unsigned int clu_base, clu_free;
- unsigned char k, clu_mask;
+ unsigned long clu_bits, clu_mask;
struct exfat_sb_info *sbi = EXFAT_SB(sb);
+ __le_long bitval;
WARN_ON(clu < EXFAT_FIRST_CLUSTER);
- ent_idx = CLUSTER_TO_BITMAP_ENT(clu);
- clu_base = BITMAP_ENT_TO_CLUSTER(ent_idx & ~(BITS_PER_BYTE_MASK));
+ ent_idx = ALIGN_DOWN(CLUSTER_TO_BITMAP_ENT(clu), BITS_PER_LONG);
+ clu_base = BITMAP_ENT_TO_CLUSTER(ent_idx);
clu_mask = IGNORED_BITS_REMAINED(clu, clu_base);
map_i = BITMAP_OFFSET_SECTOR_INDEX(sb, ent_idx);
map_b = BITMAP_OFFSET_BYTE_IN_SECTOR(sb, ent_idx);
for (i = EXFAT_FIRST_CLUSTER; i < sbi->num_clusters;
- i += BITS_PER_BYTE) {
- k = *(sbi->vol_amap[map_i]->b_data + map_b);
+ i += BITS_PER_LONG) {
+ bitval = *(__le_long *)(sbi->vol_amap[map_i]->b_data + map_b);
if (clu_mask > 0) {
- k |= clu_mask;
+ bitval |= cpu_to_lel(clu_mask);
clu_mask = 0;
}
- if (k < 0xFF) {
- clu_free = clu_base + free_bit[k];
+ if (lel_to_cpu(bitval) != ULONG_MAX) {
+ clu_bits = lel_to_cpu(bitval);
+ clu_free = clu_base + ffz(clu_bits);
if (clu_free < sbi->num_clusters)
return clu_free;
}
- clu_base += BITS_PER_BYTE;
+ clu_base += BITS_PER_LONG;
+ map_b += sizeof(long);
- if (++map_b >= sb->s_blocksize ||
+ if (map_b >= sb->s_blocksize ||
clu_base >= sbi->num_clusters) {
if (++map_i >= sbi->map_sectors) {
clu_base = EXFAT_FIRST_CLUSTER;
@@ -244,25 +228,24 @@ int exfat_count_used_clusters(struct super_block *sb, unsigned int *ret_count)
unsigned int count = 0;
unsigned int i, map_i = 0, map_b = 0;
unsigned int total_clus = EXFAT_DATA_CLUSTER_COUNT(sbi);
- unsigned int last_mask = total_clus & BITS_PER_BYTE_MASK;
- unsigned char clu_bits;
- const unsigned char last_bit_mask[] = {0, 0b00000001, 0b00000011,
- 0b00000111, 0b00001111, 0b00011111, 0b00111111, 0b01111111};
+ unsigned int last_mask = total_clus & (BITS_PER_LONG - 1);
+ unsigned long *bitmap, clu_bits;
total_clus &= ~last_mask;
- for (i = 0; i < total_clus; i += BITS_PER_BYTE) {
- clu_bits = *(sbi->vol_amap[map_i]->b_data + map_b);
- count += used_bit[clu_bits];
- if (++map_b >= (unsigned int)sb->s_blocksize) {
+ for (i = 0; i < total_clus; i += BITS_PER_LONG) {
+ bitmap = (void *)(sbi->vol_amap[map_i]->b_data + map_b);
+ count += hweight_long(*bitmap);
+ map_b += sizeof(long);
+ if (map_b >= (unsigned int)sb->s_blocksize) {
map_i++;
map_b = 0;
}
}
if (last_mask) {
- clu_bits = *(sbi->vol_amap[map_i]->b_data + map_b);
- clu_bits &= last_bit_mask[last_mask];
- count += used_bit[clu_bits];
+ bitmap = (void *)(sbi->vol_amap[map_i]->b_data + map_b);
+ clu_bits = lel_to_cpu(*(__le_long *)bitmap);
+ count += hweight_long(clu_bits & BITMAP_LAST_WORD_MASK(last_mask));
}
*ret_count = count;