From 088f1343d9108c16fca064951d85e6de9f5cab42 Mon Sep 17 00:00:00 2001 From: Yuezhang Mo Date: Tue, 16 Aug 2022 16:55:06 +0800 Subject: [PATCH] exfat: remove call ilog2() from exfat_readdir() There is no need to call ilog2() for the conversions between cluster and dentry in exfat_readdir(), because these conversions can be replaced with EXFAT_DEN_TO_CLU()/EXFAT_CLU_TO_DEN(). Code refinement, no functional changes. Signed-off-by: Yuezhang Mo Reviewed-by: Andy Wu Reviewed-by: Aoyama Wataru Reviewed-by: Sungjong Seo Signed-off-by: Namjae Jeon --- fs/exfat/dir.c | 9 ++++----- fs/exfat/exfat_fs.h | 10 ++++++++-- 2 files changed, 12 insertions(+), 7 deletions(-) diff --git a/fs/exfat/dir.c b/fs/exfat/dir.c index c05493f..397ea2d 100644 --- a/fs/exfat/dir.c +++ b/fs/exfat/dir.c @@ -61,7 +61,7 @@ static void exfat_get_uniname_from_ext_entry(struct super_block *sb, /* read a directory entry from the opened directory */ static int exfat_readdir(struct inode *inode, loff_t *cpos, struct exfat_dir_entry *dir_entry) { - int i, dentries_per_clu, dentries_per_clu_bits = 0, num_ext; + int i, dentries_per_clu, num_ext; unsigned int type, clu_offset, max_dentries; struct exfat_chain dir, clu; struct exfat_uni_name uni_name; @@ -83,11 +83,10 @@ static int exfat_readdir(struct inode *inode, loff_t *cpos, struct exfat_dir_ent EXFAT_B_TO_CLU(i_size_read(inode), sbi), ei->flags); dentries_per_clu = sbi->dentries_per_clu; - dentries_per_clu_bits = ilog2(dentries_per_clu); max_dentries = (unsigned int)min_t(u64, MAX_EXFAT_DENTRIES, - (u64)sbi->num_clusters << dentries_per_clu_bits); + (u64)EXFAT_CLU_TO_DEN(sbi->num_clusters, sbi)); - clu_offset = dentry >> dentries_per_clu_bits; + clu_offset = EXFAT_DEN_TO_CLU(dentry, sbi); exfat_chain_dup(&clu, &dir); if (clu.flags == ALLOC_NO_FAT_CHAIN) { @@ -162,7 +161,7 @@ static int exfat_readdir(struct inode *inode, loff_t *cpos, struct exfat_dir_ent dir_entry->entry = dentry; brelse(bh); - ei->hint_bmap.off = dentry >> dentries_per_clu_bits; + ei->hint_bmap.off = EXFAT_DEN_TO_CLU(dentry, sbi); ei->hint_bmap.clu = clu.dir; *cpos = EXFAT_DEN_TO_B(dentry + 1 + num_ext); diff --git a/fs/exfat/exfat_fs.h b/fs/exfat/exfat_fs.h index 324acc5..37e8af8 100644 --- a/fs/exfat/exfat_fs.h +++ b/fs/exfat/exfat_fs.h @@ -101,12 +101,18 @@ enum { /* * helpers for block size to dentry size conversion. */ -#define EXFAT_B_TO_DEN_IDX(b, sbi) \ - ((b) << ((sbi)->cluster_size_bits - DENTRY_SIZE_BITS)) #define EXFAT_B_TO_DEN(b) ((b) >> DENTRY_SIZE_BITS) #define EXFAT_DEN_TO_B(b) ((b) << DENTRY_SIZE_BITS) /* + * helpers for cluster size to dentry size conversion. + */ +#define EXFAT_CLU_TO_DEN(clu, sbi) \ + ((clu) << ((sbi)->cluster_size_bits - DENTRY_SIZE_BITS)) +#define EXFAT_DEN_TO_CLU(dentry, sbi) \ + ((dentry) >> ((sbi)->cluster_size_bits - DENTRY_SIZE_BITS)) + +/* * helpers for fat entry. */ #define FAT_ENT_SIZE (4) -- 2.7.4