Re: [PATCH] f2fs: fix to do sanity with enabled features in image

[Chao Yu <chao@kernel.org>]

On 2019-4-28 21:38, Jaegeuk Kim wrote:
> On 04/24, Chao Yu wrote:
>> This patch fixes to do sanity with enabled features in image, if
>> there are features kernel can not recognize, just fail the mount.
> 
> We need to figure out per-feature-based rejection, since some of them can
> be set without layout change.

So any suggestion on how to implement this?

Maybe:

if (LINUX_VERSION_CODE < KERNEL_VERSION(4, 14, 0))
	check 4.14+ features
else if (LINUX_VERSION_CODE < KERNEL_VERSION(4, 9, 0))
	check 4.9+ features
else if (LINUX_VERSION_CODE < KERNEL_VERSION(4, 4, 0))
	check 4.4+ features

Thanks,

> 
>>
>> Signed-off-by: Chao Yu <yuchao0@huawei.com>
>> ---
>>  fs/f2fs/f2fs.h  | 13 +++++++++++++
>>  fs/f2fs/super.c |  9 +++++++++
>>  2 files changed, 22 insertions(+)
>>
>> diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
>> index f5ffc09705eb..15b640967e12 100644
>> --- a/fs/f2fs/f2fs.h
>> +++ b/fs/f2fs/f2fs.h
>> @@ -151,6 +151,19 @@ struct f2fs_mount_info {
>>  #define F2FS_FEATURE_VERITY		0x0400	/* reserved */
>>  #define F2FS_FEATURE_SB_CHKSUM		0x0800
>>  
>> +#define F2FS_ALL_FEATURES	(F2FS_FEATURE_ENCRYPT |			\
>> +				F2FS_FEATURE_BLKZONED |			\
>> +				F2FS_FEATURE_ATOMIC_WRITE |		\
>> +				F2FS_FEATURE_EXTRA_ATTR |		\
>> +				F2FS_FEATURE_PRJQUOTA |			\
>> +				F2FS_FEATURE_INODE_CHKSUM |		\
>> +				F2FS_FEATURE_FLEXIBLE_INLINE_XATTR |	\
>> +				F2FS_FEATURE_QUOTA_INO |		\
>> +				F2FS_FEATURE_INODE_CRTIME |		\
>> +				F2FS_FEATURE_LOST_FOUND |		\
>> +				F2FS_FEATURE_VERITY |			\
>> +				F2FS_FEATURE_SB_CHKSUM)
>> +
>>  #define __F2FS_HAS_FEATURE(raw_super, mask)				\
>>  	((raw_super->feature & cpu_to_le32(mask)) != 0)
>>  #define F2FS_HAS_FEATURE(sbi, mask)	__F2FS_HAS_FEATURE(sbi->raw_super, mask)
>> diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
>> index 4f8e9ab48b26..57f2fc6d14ba 100644
>> --- a/fs/f2fs/super.c
>> +++ b/fs/f2fs/super.c
>> @@ -2573,6 +2573,15 @@ static int sanity_check_raw_super(struct f2fs_sb_info *sbi,
>>  		return 1;
>>  	}
>>  
>> +	/* check whether kernel supports all features */
>> +	if (le32_to_cpu(raw_super->feature) & (~F2FS_ALL_FEATURES)) {
>> +		f2fs_msg(sb, KERN_INFO,
>> +			"Unsupported feature:%u: supported:%u",
>> +			le32_to_cpu(raw_super->feature),
>> +			F2FS_ALL_FEATURES);
>> +		return 1;
>> +	}
>> +
>>  	/* check CP/SIT/NAT/SSA/MAIN_AREA area boundary */
>>  	if (sanity_check_area_boundary(sbi, bh))
>>  		return 1;
>> -- 
>> 2.18.0.rc1