[PATCH 6/8] staging: erofs: avoid magic constants when initializing clusterbits

From: Gao Xiang
Date: Fri Sep 14 2018 - 10:43:12 EST


Currently erofs only supports clustersize == blocksize.
and clustersize == 2^n * blocksize will be supported in the future.

Reviewed-by: Chao Yu <yuchao0@xxxxxxxxxx>
Signed-off-by: Gao Xiang <gaoxiang25@xxxxxxxxxx>
---
drivers/staging/erofs/super.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/staging/erofs/super.c b/drivers/staging/erofs/super.c
index 2109b03..9e42153 100644
--- a/drivers/staging/erofs/super.c
+++ b/drivers/staging/erofs/super.c
@@ -116,9 +116,10 @@ static int superblock_read(struct super_block *sb)
#endif
sbi->islotbits = ffs(sizeof(struct erofs_inode_v1)) - 1;
#ifdef CONFIG_EROFS_FS_ZIP
- sbi->clusterbits = 12;
+ /* TODO: clusterbits should be related to inode */
+ sbi->clusterbits = blkszbits;

- if (1 << (sbi->clusterbits - 12) > Z_EROFS_CLUSTER_MAX_PAGES)
+ if (1 << (sbi->clusterbits - PAGE_SHIFT) > Z_EROFS_CLUSTER_MAX_PAGES)
errln("clusterbits %u is not supported on this kernel",
sbi->clusterbits);
#endif
--
1.9.1