diff options
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/nilfs2/bmap.c | 15 |
1 files changed, 11 insertions, 4 deletions
diff --git a/fs/nilfs2/bmap.c b/fs/nilfs2/bmap.c index 824f2bd91c16..5f0f1f283af0 100644 --- a/fs/nilfs2/bmap.c +++ b/fs/nilfs2/bmap.c @@ -450,18 +450,25 @@ __u64 nilfs_bmap_find_target_seq(const struct nilfs_bmap *bmap, __u64 key) return NILFS_BMAP_INVALID_PTR; } -#define NILFS_BMAP_GROUP_DIV 8 +#define NILFS_BMAP_GROUP_DIV 8 /* must be power of 2 */ + __u64 nilfs_bmap_find_target_in_group(const struct nilfs_bmap *bmap) { struct inode *dat = nilfs_bmap_get_dat(bmap); unsigned long entries_per_group = nilfs_palloc_entries_per_group(dat); - unsigned long group = bmap->b_inode->i_ino / entries_per_group; + unsigned long group; + u32 index; + + BUILD_BUG_ON_NOT_POWER_OF_2(NILFS_BMAP_GROUP_DIV); + + group = div_u64(bmap->b_inode->i_ino, entries_per_group); + index = bmap->b_inode->i_ino & (NILFS_BMAP_GROUP_DIV - 1); return group * entries_per_group + - (bmap->b_inode->i_ino % NILFS_BMAP_GROUP_DIV) * - (entries_per_group / NILFS_BMAP_GROUP_DIV); + index * (entries_per_group / NILFS_BMAP_GROUP_DIV); } + static struct lock_class_key nilfs_bmap_dat_lock_key; static struct lock_class_key nilfs_bmap_mdt_lock_key; |