diff options
Diffstat (limited to 'fs/exfat/balloc.c')
| -rw-r--r-- | fs/exfat/balloc.c | 87 |
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; |