On 3/22/2017 18:16, Chao Yu wrote:
> On 2017/3/22 16:42, Chao Yu wrote:
>> On 2017/3/22 0:18, Jaegeuk Kim wrote:
>>> On 03/20, Kinglong Mee wrote:
>>>> On 3/20/2017 11:08, Jaegeuk Kim wrote:
>>>>> Hi Kinglong,
>>>>>
>>>>> On 03/18, Kinglong Mee wrote:
>>>>>> It's better coping all valid xattr data includes the last zero. 
>>>>>
>>>>> Why do we need this?
>>>>>
>>>>> The size of txattr_addr would be larger than the space we need.
>>>>>
>>>>> Thanks,
>>>>>
>>>>>>
>>>>>> Signed-off-by: Kinglong Mee <kinglong...@gmail.com>
>>>>>> ---
>>>>>>  fs/f2fs/xattr.c | 4 ++--
>>>>>>  fs/f2fs/xattr.h | 4 ++--
>>>>>>  2 files changed, 4 insertions(+), 4 deletions(-)
>>>>>>
>>>>>> diff --git a/fs/f2fs/xattr.c b/fs/f2fs/xattr.c
>>>>>> index aff7619..41785c9 100644
>>>>>> --- a/fs/f2fs/xattr.c
>>>>>> +++ b/fs/f2fs/xattr.c
>>>>>> @@ -249,7 +249,7 @@ static int lookup_all_xattrs(struct inode *inode, 
>>>>>> struct page *ipage,
>>>>>>          struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
>>>>>>          void *cur_addr, *txattr_addr, *last_addr = NULL;
>>>>>>          nid_t xnid = F2FS_I(inode)->i_xattr_nid;
>>>>>> -        unsigned int size = xnid ? VALID_XATTR_BLOCK_SIZE : 0;
>>>>
>>>> Here maybe does not copy the last zero.
>>>
>>> The below kzalloc() will make it zero. Any problem?
>>
>> There is no problem without this change, but anyway, IMO, it needs to do 
>> cleanup
>> as it can provider better readability making allocated size and copied size 
>> be
>> consistent among lookup_all_xattrs, read_all_xattrs and write_all_xattrs.
>>
>> And since during allocation we have initialize memory with zero, so I prefer 
>> to
>> not copy extra reserved xattr space.
>>
>> Jaegeuk, Kinglong, how about changing like below:
>>
>> ---
>>  fs/f2fs/xattr.c | 27 ++++++++++++---------------
>>  fs/f2fs/xattr.h |  3 ++-
>>  2 files changed, 14 insertions(+), 16 deletions(-)
>>
>> diff --git a/fs/f2fs/xattr.c b/fs/f2fs/xattr.c
>> index aff7619e3f96..308b06664068 100644
>> --- a/fs/f2fs/xattr.c
>> +++ b/fs/f2fs/xattr.c
>> @@ -250,15 +250,13 @@ static int lookup_all_xattrs(struct inode *inode, 
>> struct
>> page *ipage,
>>      void *cur_addr, *txattr_addr, *last_addr = NULL;
>>      nid_t xnid = F2FS_I(inode)->i_xattr_nid;
>>      unsigned int size = xnid ? VALID_XATTR_BLOCK_SIZE : 0;
>> -    unsigned int inline_size = 0;
>> +    unsigned int inline_size = inline_xattr_size(inode);
>>      int err = 0;
>>
>> -    inline_size = inline_xattr_size(inode);
>> -
>>      if (!size && !inline_size)
>>              return -ENODATA;
>>
>> -    txattr_addr = kzalloc(inline_size + size + sizeof(__u32),
>> +    txattr_addr = kzalloc(inline_size + size + RESERVED_XATTR_SIZE,
>>                                                      GFP_F2FS_ZERO);
>>      if (!txattr_addr)
>>              return -ENOMEM;
>> @@ -328,13 +326,14 @@ static int read_all_xattrs(struct inode *inode, struct
>> page *ipage,
>>  {
>>      struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
>>      struct f2fs_xattr_header *header;
>> -    size_t size = PAGE_SIZE, inline_size = 0;
>> +    nid_t xnid = F2FS_I(inode)->i_xattr_nid;
>> +    unsigned int size = xnid ? VALID_XATTR_BLOCK_SIZE : 0;
> 
> Here, always should assign size with VALID_XATTR_BLOCK_SIZE for enospc case in
> inline xattr space while adding new xattr entry.
> 
> unsigned int size = VALID_XATTR_BLOCK_SIZE;

It's better that mine.

Reviewed-by: Kinglong Mee <kinglong...@gmail.com>

Thanks,
Kinglong Mee

> 
> Thanks,
> 
>> +    unsigned int inline_size = inline_xattr_size(inode);
>>      void *txattr_addr;
>>      int err;
>>
>> -    inline_size = inline_xattr_size(inode);
>> -
>> -    txattr_addr = kzalloc(inline_size + size, GFP_F2FS_ZERO);
>> +    txattr_addr = kzalloc(inline_size + size + RESERVED_XATTR_SIZE,
>> +                                                    GFP_F2FS_ZERO);
>>      if (!txattr_addr)
>>              return -ENOMEM;
>>
>> @@ -358,19 +357,19 @@ static int read_all_xattrs(struct inode *inode, struct
>> page *ipage,
>>      }
>>
>>      /* read from xattr node block */
>> -    if (F2FS_I(inode)->i_xattr_nid) {
>> +    if (xnid) {
>>              struct page *xpage;
>>              void *xattr_addr;
>>
>>              /* The inode already has an extended attribute block. */
>> -            xpage = get_node_page(sbi, F2FS_I(inode)->i_xattr_nid);
>> +            xpage = get_node_page(sbi, xnid);
>>              if (IS_ERR(xpage)) {
>>                      err = PTR_ERR(xpage);
>>                      goto fail;
>>              }
>>
>>              xattr_addr = page_address(xpage);
>> -            memcpy(txattr_addr + inline_size, xattr_addr, PAGE_SIZE);
>> +            memcpy(txattr_addr + inline_size, xattr_addr, size);
>>              f2fs_put_page(xpage, 1);
>>      }
>>
>> @@ -392,14 +391,12 @@ static inline int write_all_xattrs(struct inode *inode,
>> __u32 hsize,
>>                              void *txattr_addr, struct page *ipage)
>>  {
>>      struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
>> -    size_t inline_size = 0;
>> +    size_t inline_size = inline_xattr_size(inode);
>>      void *xattr_addr;
>>      struct page *xpage;
>>      nid_t new_nid = 0;
>>      int err;
>>
>> -    inline_size = inline_xattr_size(inode);
>> -
>>      if (hsize > inline_size && !F2FS_I(inode)->i_xattr_nid)
>>              if (!alloc_nid(sbi, &new_nid))
>>                      return -ENOSPC;
>> @@ -454,7 +451,7 @@ static inline int write_all_xattrs(struct inode *inode,
>> __u32 hsize,
>>      }
>>
>>      xattr_addr = page_address(xpage);
>> -    memcpy(xattr_addr, txattr_addr + inline_size, MAX_XATTR_BLOCK_SIZE);
>> +    memcpy(xattr_addr, txattr_addr + inline_size, VALID_XATTR_BLOCK_SIZE);
>>      set_page_dirty(xpage);
>>      f2fs_put_page(xpage, 1);
>>
>> diff --git a/fs/f2fs/xattr.h b/fs/f2fs/xattr.h
>> index d5a94928c116..1e7db8d0806e 100644
>> --- a/fs/f2fs/xattr.h
>> +++ b/fs/f2fs/xattr.h
>> @@ -73,7 +73,8 @@ struct f2fs_xattr_entry {
>>                              !IS_XATTR_LAST_ENTRY(entry);\
>>                              entry = XATTR_NEXT_ENTRY(entry))
>>  #define MAX_XATTR_BLOCK_SIZE        (PAGE_SIZE - sizeof(struct node_footer))
>> -#define VALID_XATTR_BLOCK_SIZE      (MAX_XATTR_BLOCK_SIZE - sizeof(__u32))
>> +#define RESERVED_XATTR_SIZE (sizeof(__u32))
>> +#define VALID_XATTR_BLOCK_SIZE      (MAX_XATTR_BLOCK_SIZE - 
>> RESERVED_XATTR_SIZE)
>>  #define MIN_OFFSET(i)               XATTR_ALIGN(inline_xattr_size(i) +      
>> \
>>                                              VALID_XATTR_BLOCK_SIZE)
>>
> 
> 

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