Re: [PATCH v6 09/10] xfs: add minimum file size filtering to eofblocks scan

Mark Tinguely
2012-11-06T19:21:48Z

On 11/06/12 12:00, Brian Foster wrote:
> On 11/06/2012 12:08 PM, Roger Willcocks wrote:
>>
>> On Tue, 2012-11-06 at 10:57 -0600, Mark Tinguely wrote:
>>> On 11/06/12 08:50, Brian Foster wrote:
>>>> Support minimum file size filtering in the eofblocks scan. The
>>>> caller must set the XFS_EOF_FLAGS_MINFILESIZE flags bit and minimum
>>>> file size value in bytes.
>>>>
>>>> Signed-off-by: Brian Foster<bfoster@redhat.com>
>>>> ---
>>>> fs/xfs/xfs_fs.h | 6 ++++--
>>>> fs/xfs/xfs_icache.c | 11 +++++++++--
>>>> 2 files changed, 13 insertions(+), 4 deletions(-)
>>>>
>>>> diff --git a/fs/xfs/xfs_fs.h b/fs/xfs/xfs_fs.h
>>>> index 88eb1bc..082b743 100644
>>>> --- a/fs/xfs/xfs_fs.h
>>>> +++ b/fs/xfs/xfs_fs.h
>>>> @@ -348,7 +348,8 @@ struct xfs_eofblocks {
>>>> uid_t eof_uid;
>>>> gid_t eof_gid;
>>>> prid_t eof_prid;
>>>> - __u32 pad[27];
>>>> + __u64 eof_min_file_size;
>>>> + __u32 pad[25]
>>> ^^
>>> Glad you bumped it to a unsigned 64 bit value.
>>> Are __u64 items 64 bits? if so, the pad would be 24
>>>
>>
>> It should probably be:
>>
>> __u32 pad_align_64;
>> __u64 eof_min_file_size;
>> __u32 pad[24];
>>
>
> Doh... forgot about alignment. Thanks for catching that guys.
>
> The new pad_align field means I have to fix up the padded zero check as
> well, which makes me wonder if I should reorder things now or actually
> split more of the padding space into two (__u32/__u64, rather than
> mistakenly converting to a __u32 like I've done here) fields to support
> extending the data structure with fields of either size without having
> to update the version. E.g., we end up with something like the following:
>
> struct xfs_eofblocks {
> __u32 version;
> __u32 flags;
> uid_t uid;
> gid_t gid;
> prid_t prid;
> __u32 pad32[9];
> __u64 minfilesize;
> __u64 pad64[8];
> };
>
> Thoughts?
>
> Brian
>

I vote to keep the padding continuous at the end of the series
and the padding check simple:

struct xfs_eofblocks {
__u32 version;
__u32 flags;
__u64 minfilesize;
uid_t uid;
gid_t gid;
prid_t prid;
__u32 pad32[25];
}

--Mark.