Re: [f2fs-dev] [PATCH 1/2] f2fs: show precise # of blocks that user/root can use

From: Chao Yu
Date: Mon Jan 08 2018 - 06:23:37 EST


On 2018/1/5 15:05, Yunlong Song wrote:
> NACK
>
> man statfs shows:
>
> struct statfs {
> ...
> fsblkcnt_t f_bfree; /* free blocks in fs */
> fsblkcnt_t f_bavail; /* free blocks available to
> unprivileged user */
> ...
> }
>
> f_bfree is free blocks in fs, so buf->bfree should be
>
> buf->f_bfree = user_block_count - valid_user_blocks(sbi) + ovp_count;

As I checked, some filesystems reserving over-privision space like
btrfs/xfs/ubifs, they will not calculate those space into f_bfree, IMO, we
should follow their behavior to keep compatibility for old applications.

Thanks,

>
> On 2018/1/4 2:58, Jaegeuk Kim wrote:
>> Let's show precise # of blocks that user/root can use through bavail and bfree
>> respectively.
>>
>> Signed-off-by: Jaegeuk Kim <jaegeuk@xxxxxxxxxx>
>> ---
>> fs/f2fs/super.c | 4 ++--
>> 1 file changed, 2 insertions(+), 2 deletions(-)
>>
>> diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
>> index 0a820ba55b10..4c1c99cf54ef 100644
>> --- a/fs/f2fs/super.c
>> +++ b/fs/f2fs/super.c
>> @@ -1005,9 +1005,9 @@ static int f2fs_statfs(struct dentry *dentry, struct kstatfs *buf)
>> buf->f_bsize = sbi->blocksize;
>>
>> buf->f_blocks = total_count - start_count;
>> - buf->f_bfree = user_block_count - valid_user_blocks(sbi) + ovp_count;
>> - buf->f_bavail = user_block_count - valid_user_blocks(sbi) -
>> + buf->f_bfree = user_block_count - valid_user_blocks(sbi) -
>> sbi->current_reserved_blocks;
>> + buf->f_bavail = buf->f_bfree;
>>
>> avail_node_count = sbi->total_node_count - sbi->nquota_files -
>> F2FS_RESERVED_NODE_NUM;
>