Re: [PATCH] nfs: don't update isize when NFS_INO_LAYOUTCOMMITTING in nfs_update_inode

Trond Myklebust
2014-01-13T16:28:27Z

On Jan 13, 2014, at 8:34, Trond Myklebust <trond.myklebust@primarydata.com> wrote:

>
> On Jan 13, 2014, at 2:55, shaobingqing <shaobingqing@bwstor.com.cn> wrote:
>
>> When a file is in NFS_INO_LAYOUTCOMMITING status, its isize perhaps has not been
>> transferred to the metadate server. So the isize getting from the metadata server
>> perhaps is out of date and cannot be used to update the isize of the client.
>>
>> Signed-off-by: shaobingqing <shaobingqing@bwstor.com.cn>
>> ---
>> fs/nfs/inode.c | 3 ++-
>> 1 files changed, 2 insertions(+), 1 deletions(-)
>>
>> diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
>> index ebeb94c..caf50a1 100644
>> --- a/fs/nfs/inode.c
>> +++ b/fs/nfs/inode.c
>> @@ -1402,7 +1402,8 @@ static int nfs_update_inode(struct inode *inode, struct nfs_fattr *fattr)
>> if (new_isize != cur_isize) {
>> /* Do we perhaps have any outstanding writes, or has
>> * the file grown beyond our last write? */
>> - if ((nfsi->npages == 0 && !test_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags)) ||
>> + if ((nfsi->npages == 0 && !test_bit(NFS_INO_LAYOUTCOMMIT, &nfsi->flags) &&
>> + !test_bit(NFS_INO_LAYOUTCOMMITTING, &nfsi->flags)) ||
>> new_isize > cur_isize) {
>> i_size_write(inode, new_isize);
>> invalid |= NFS_INO_INVALID_ATTR|NFS_INO_INVALID_DATA;
>
> Ugh. Is there any reason why we can’t just keep NFS_INO_LAYOUTCOMMIT set until the layout commit operation is finished instead of multiplying the tests for it in generic NFS code paths such as nfs_update_inode?

Actually, no. The above is bogus, because LAYOUTCOMMIT doesn’t just affect the file size: it affects the NFSv4 change attribute, ctime and mtime values too.

I’ll draft a patch...

--
Trond Myklebust
Linux NFS client maintainer