diff options
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/ext4/ext4.h | 29 | ||||
| -rw-r--r-- | fs/ext4/super.c | 1 |
2 files changed, 14 insertions, 16 deletions
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index e20dc38858d4..b79d613091d0 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -463,25 +463,22 @@ enum { EXT4_INODE_RESERVED = 31, /* reserved for ext4 lib */ }; -#define TEST_FLAG_VALUE(FLAG) (EXT4_##FLAG##_FL == (1 << EXT4_INODE_##FLAG)) -#define CHECK_FLAG_VALUE(FLAG) if (!TEST_FLAG_VALUE(FLAG)) { \ - printk(KERN_EMERG "EXT4 flag fail: " #FLAG ": %d %d\n", \ - EXT4_##FLAG##_FL, EXT4_INODE_##FLAG); BUG_ON(1); } - -/* - * Since it's pretty easy to mix up bit numbers and hex values, and we - * can't do a compile-time test for ENUM values, we use a run-time - * test to make sure that EXT4_XXX_FL is consistent with respect to - * EXT4_INODE_XXX. If all is well the printk and BUG_ON will all drop - * out so it won't cost any extra space in the compiled kernel image. - * But it's important that these values are the same, since we are - * using EXT4_INODE_XXX to test for the flag values, but EXT4_XX_FL - * must be consistent with the values of FS_XXX_FL defined in - * include/linux/fs.h and the on-disk values found in ext2, ext3, and - * ext4 filesystems, and of course the values defined in e2fsprogs. +/* + * Since it's pretty easy to mix up bit numbers and hex values, we use a + * build-time check to make sure that EXT4_XXX_FL is consistent with respect to + * EXT4_INODE_XXX. If all is well, the macros will be dropped, so, it won't cost + * any extra space in the compiled kernel image, otherwise, the build will fail. + * It's important that these values are the same, since we are using + * EXT4_INODE_XXX to test for flag values, but EXT4_XXX_FL must be consistent + * with the values of FS_XXX_FL defined in include/linux/fs.h and the on-disk + * values found in ext2, ext3 and ext4 filesystems, and of course the values + * defined in e2fsprogs. * * It's not paranoia if the Murphy's Law really *is* out to get you. :-) */ +#define TEST_FLAG_VALUE(FLAG) (EXT4_##FLAG##_FL == (1 << EXT4_INODE_##FLAG)) +#define CHECK_FLAG_VALUE(FLAG) BUILD_BUG_ON(!TEST_FLAG_VALUE(FLAG)) + static inline void ext4_check_flag_values(void) { CHECK_FLAG_VALUE(SECRM); diff --git a/fs/ext4/super.c b/fs/ext4/super.c index 7d53adff8bd3..3cdb0a2fc648 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -5278,6 +5278,7 @@ static int __init ext4_init_fs(void) ext4_li_info = NULL; mutex_init(&ext4_li_mtx); + /* Build-time check for flags consistency */ ext4_check_flag_values(); for (i = 0; i < EXT4_WQ_HASH_SZ; i++) { |