Re: [PATCH] f2fs: fix to keep backward compatibility of flexible inline xattr feature

[Chao Yu <yuchao0@huawei.com>]

Hi Jaegeuk,

On 2017/10/26 16:42, Jaegeuk Kim wrote:
> Hi Chao,
> 
> It seems this is a critical problem, so let me integrate this patch with your
> initial patch "f2fs: support flexible inline xattr size".
> Let me know, if you have any other concern.

Better. ;)

Please add commit message of this patch into initial patch "f2fs: support
flexible inline xattr size".

And please fix related issue in f2fs-tools with below diff code:

---
 include/f2fs_fs.h | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/include/f2fs_fs.h b/include/f2fs_fs.h
index 2db7495804fd..a0e15ba85d97 100644
--- a/include/f2fs_fs.h
+++ b/include/f2fs_fs.h
@@ -1047,11 +1047,14 @@ static inline int __get_extra_isize(struct f2fs_inode *inode)
 extern struct f2fs_configuration c;
 static inline int get_inline_xattr_addrs(struct f2fs_inode *inode)
 {
-	if (!(inode->i_inline & F2FS_INLINE_XATTR))
+	if ((c.feature & cpu_to_le32(F2FS_FEATURE_EXTRA_ATTR)) &&
+		(c.feature & cpu_to_le32(F2FS_FEATURE_FLEXIBLE_INLINE_XATTR)))
+		return le16_to_cpu(inode->i_inline_xattr_size);
+	else if (!(inode->i_inline & F2FS_INLINE_XATTR) &&
+		(S_ISREG(inode->i_mode) || S_ISLNK(inode->i_mode)))
 		return 0;
-	if (!(c.feature & cpu_to_le32(F2FS_FEATURE_FLEXIBLE_INLINE_XATTR)))
+	else
 		return DEFAULT_INLINE_XATTR_ADDRS;
-	return le16_to_cpu(inode->i_inline_xattr_size);
 }

 #define get_extra_isize(node)	__get_extra_isize(&node->i)
-- 

Thanks,

> 
> Thanks,
> 
> On 10/25, Chao Yu wrote:
>> Previously, in inode layout, we will always reserve 200 bytes for inline
>> xattr space no matter the inode enables inline xattr feature or not, due
>> to this reason, max inline size of inode is fixed, but now, if inline
>> xattr is not enabled, max inline size of inode will be enlarged by 200
>> bytes, for regular and symlink inode, it will be safe to reuse resevered
>> space as they are all zero, but for directory, we need to keep the
>> reservation for stablizing directory structure.
>>
>> Reported-by: Sheng Yong <shengyong1@huawei.com>
>> Signed-off-by: Chao Yu <yuchao0@huawei.com>
>> ---
>>  fs/f2fs/f2fs.h  |  5 +----
>>  fs/f2fs/inode.c | 15 ++++++++++++---
>>  fs/f2fs/namei.c |  2 ++
>>  3 files changed, 15 insertions(+), 7 deletions(-)
>>
>> diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
>> index 2af1d31ae74b..7ddd0d085e3b 100644
>> --- a/fs/f2fs/f2fs.h
>> +++ b/fs/f2fs/f2fs.h
>> @@ -2393,10 +2393,7 @@ static inline int get_extra_isize(struct inode *inode)
>>  static inline int f2fs_sb_has_flexible_inline_xattr(struct super_block *sb);
>>  static inline int get_inline_xattr_addrs(struct inode *inode)
>>  {
>> -	if (!f2fs_has_inline_xattr(inode))
>> -		return 0;
>> -	if (!f2fs_sb_has_flexible_inline_xattr(F2FS_I_SB(inode)->sb))
>> -		return DEFAULT_INLINE_XATTR_ADDRS;
>> +
>>  	return F2FS_I(inode)->i_inline_xattr_size;
>>  }
>>  
>> diff --git a/fs/f2fs/inode.c b/fs/f2fs/inode.c
>> index bb876737e653..7f31b22c9efa 100644
>> --- a/fs/f2fs/inode.c
>> +++ b/fs/f2fs/inode.c
>> @@ -232,10 +232,19 @@ static int do_read_inode(struct inode *inode)
>>  	fi->i_extra_isize = f2fs_has_extra_attr(inode) ?
>>  					le16_to_cpu(ri->i_extra_isize) : 0;
>>  
>> -	if (!f2fs_has_inline_xattr(inode))
>> -		fi->i_inline_xattr_size = 0;
>> -	else if (f2fs_sb_has_flexible_inline_xattr(sbi->sb))
>> +	/*
>> +	 * Previously, we will always reserve DEFAULT_INLINE_XATTR_ADDRS size
>> +	 * space for inline xattr datas, if inline xattr is not enabled, we
>> +	 * can expect all zero in reserved area, so for regular or symlink,
>> +	 * it will be safe to reuse reserved area, but for directory, we
>> +	 * should keep the reservation for stablizing directory structure.
>> +	 */
>> +	if (f2fs_has_extra_attr(inode) &&
>> +		f2fs_sb_has_flexible_inline_xattr(sbi->sb))
>>  		fi->i_inline_xattr_size = le16_to_cpu(ri->i_inline_xattr_size);
>> +	else if (!f2fs_has_inline_xattr(inode) &&
>> +		(S_ISREG(inode->i_mode) || S_ISLNK(inode->i_mode)))
>> +		fi->i_inline_xattr_size = 0;
>>  	else
>>  		fi->i_inline_xattr_size = DEFAULT_INLINE_XATTR_ADDRS;
>>  
>> diff --git a/fs/f2fs/namei.c b/fs/f2fs/namei.c
>> index e6f86d5d97b9..a1c56a14c191 100644
>> --- a/fs/f2fs/namei.c
>> +++ b/fs/f2fs/namei.c
>> @@ -91,6 +91,8 @@ static struct inode *f2fs_new_inode(struct inode *dir, umode_t mode)
>>  		f2fs_sb_has_flexible_inline_xattr(sbi->sb) &&
>>  		f2fs_has_inline_xattr(inode))
>>  		F2FS_I(inode)->i_inline_xattr_size = sbi->inline_xattr_size;
>> +	else
>> +		F2FS_I(inode)->i_inline_xattr_size = 0;
>>  
>>  	if (test_opt(sbi, INLINE_DATA) && f2fs_may_inline_data(inode))
>>  		set_inode_flag(inode, FI_INLINE_DATA);
>> -- 
>> 2.13.1.388.g69e6b9b4f4a9
> 
> .
>