From e22a444275d1e7c80db5d8bec08fb8d0d79617ad Mon Sep 17 00:00:00 2001 From: Namjae Jeon Date: Mon, 29 Apr 2013 16:21:10 -0700 Subject: fat: introduce a helper fat_get_blknr_offset() Introduce helper function to get the block number and offset for a given i_pos value. Use it in __fat_write_inode() now and later on in nfs.c Signed-off-by: Namjae Jeon Signed-off-by: Ravishankar N Signed-off-by: Amit Sahrawat Acked-by: OGAWA Hirofumi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/fat/fat.h | 7 +++++++ fs/fat/inode.c | 9 +++++---- 2 files changed, 12 insertions(+), 4 deletions(-) diff --git a/fs/fat/fat.h b/fs/fat/fat.h index f16948ed5bf..980c0346c16 100644 --- a/fs/fat/fat.h +++ b/fs/fat/fat.h @@ -218,6 +218,13 @@ static inline sector_t fat_clus_to_blknr(struct msdos_sb_info *sbi, int clus) + sbi->data_start; } +static inline void fat_get_blknr_offset(struct msdos_sb_info *sbi, + loff_t i_pos, sector_t *blknr, int *offset) +{ + *blknr = i_pos >> sbi->dir_per_block_bits; + *offset = i_pos & (sbi->dir_per_block - 1); +} + static inline loff_t fat_i_pos_read(struct msdos_sb_info *sbi, struct inode *inode) { diff --git a/fs/fat/inode.c b/fs/fat/inode.c index 78e363c844c..68cb5a6eb53 100644 --- a/fs/fat/inode.c +++ b/fs/fat/inode.c @@ -662,7 +662,8 @@ static int __fat_write_inode(struct inode *inode, int wait) struct buffer_head *bh; struct msdos_dir_entry *raw_entry; loff_t i_pos; - int err; + sector_t blocknr; + int err, offset; if (inode->i_ino == MSDOS_ROOT_INO) return 0; @@ -672,7 +673,8 @@ retry: if (!i_pos) return 0; - bh = sb_bread(sb, i_pos >> sbi->dir_per_block_bits); + fat_get_blknr_offset(sbi, i_pos, &blocknr, &offset); + bh = sb_bread(sb, blocknr); if (!bh) { fat_msg(sb, KERN_ERR, "unable to read inode block " "for updating (i_pos %lld)", i_pos); @@ -685,8 +687,7 @@ retry: goto retry; } - raw_entry = &((struct msdos_dir_entry *) (bh->b_data)) - [i_pos & (sbi->dir_per_block - 1)]; + raw_entry = &((struct msdos_dir_entry *) (bh->b_data))[offset]; if (S_ISDIR(inode->i_mode)) raw_entry->size = 0; else -- cgit v1.2.3