Looks good, some minor comments below. I'm wondering how to test that.
We'd have to inject either the corruption or to provide a way to
forcibly fail the test. For the latter a debugfs should do, I'll send
something for comments.

On Thu, Apr 19, 2018 at 05:38:16PM +0800, Qu Wenruo wrote:
> @@ -3563,6 +3565,12 @@ int write_all_supers(struct btrfs_fs_info *fs_info, 
> int max_mirrors)
>       sb = fs_info->super_for_commit;
>       dev_item = &sb->dev_item;
>  
> +     if (btrfs_check_super_valid(fs_info, sb, -1)) {

A comment that this is skipping the bytenr check would be good.

> +             btrfs_err(fs_info,
> +             "superblock corruption detected before transaction commitment");

                                                                   commit


> +             return -EUCLEAN;
> +     }
> +
>       mutex_lock(&fs_info->fs_devices->device_list_mutex);
>       head = &fs_info->fs_devices->devices;
>       max_errors = btrfs_super_num_devices(fs_info->super_copy) - 1;
> @@ -3974,9 +3982,18 @@ int btrfs_read_buffer(struct extent_buffer *buf, u64 
> parent_transid, int level,
>                                             level, first_key);
>  }
>  
> -static int btrfs_check_super_valid(struct btrfs_fs_info *fs_info)
> +/*
> + * Check the validation of btrfs super block.
> + *
> + * @sb:                      super block to check
> + * @super_mirror:    the super block number to check its bytenr.
> + *                   0 means the primary (1st) sb, 1 and 2 means 2nd and
> + *                   3rd backup sb, while -1 means to skip bytenr check.
> + */
> +static int btrfs_check_super_valid(struct btrfs_fs_info *fs_info,
> +                                struct btrfs_super_block *sb,
> +                                int super_mirror)
>  {
> -     struct btrfs_super_block *sb = fs_info->super_copy;
>       u64 nodesize = btrfs_super_nodesize(sb);
>       u64 sectorsize = btrfs_super_sectorsize(sb);
>       int ret = 0;
> @@ -4019,7 +4036,7 @@ static int btrfs_check_super_valid(struct btrfs_fs_info 
> *fs_info)
>        * Check sectorsize and nodesize first, other check will need it.
>        * Check all possible sectorsize(4K, 8K, 16K, 32K, 64K) here.
>        */
> -     if (!is_power_of_2(sectorsize) || sectorsize < 4096 ||
> +     if (!is_power_of_2(sectorsize) || sectorsize < SZ_4K ||

No unrelated changes please. There are some remaining raw values, send a
separate patch if you want to convert them.

>           sectorsize > BTRFS_MAX_METADATA_BLOCKSIZE) {
>               btrfs_err(fs_info, "invalid sectorsize %llu", sectorsize);
>               ret = -EINVAL;
> @@ -4088,9 +4105,10 @@ static int btrfs_check_super_valid(struct 
> btrfs_fs_info *fs_info)
>               ret = -EINVAL;
>       }
>  
> -     if (btrfs_super_bytenr(sb) != BTRFS_SUPER_INFO_OFFSET) {
> -             btrfs_err(fs_info, "super offset mismatch %llu != %u",
> -                       btrfs_super_bytenr(sb), BTRFS_SUPER_INFO_OFFSET);
> +     if (super_mirror >= 0 && btrfs_super_bytenr(sb) !=
> +         btrfs_sb_offset(super_mirror)) {
> +             btrfs_err(fs_info, "super offset mismatch %llu != %llu",
> +                     btrfs_super_bytenr(sb), btrfs_sb_offset(super_mirror));
>               ret = -EINVAL;
>       }
>  
> -- 
> 2.17.0
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
> the body of a message to [email protected]
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
--
To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to