Re: [PATCH RFC v15 04/11] NFSD: Update nfsd_breaker_owns_lease() to handle courtesy clients

[dai.ngo@oracle.com]

On 3/9/22 1:46 PM, Chuck Lever III wrote:
>
>> On Mar 4, 2022, at 7:37 PM, Dai Ngo <dai.ngo@oracle.com> wrote:
>>
>> Update nfsd_breaker_owns_lease() to handle delegation conflict
>> with courtesy clients. If conflict was caused courtesy client
>> then discard the courtesy client by setting CLIENT_EXPIRED and
>> return conflict resolved. Client with CLIENT_EXPIRED is expired
>> by the laundromat.
>>
>> Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
>> ---
>> fs/nfsd/nfs4state.c | 18 ++++++++++++++++++
>> 1 file changed, 18 insertions(+)
>>
>> diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
>> index 583ac807e98d..40a357fd1a14 100644
>> --- a/fs/nfsd/nfs4state.c
>> +++ b/fs/nfsd/nfs4state.c
>> @@ -4727,6 +4727,24 @@ static bool nfsd_breaker_owns_lease(struct file_lock *fl)
>> 	struct svc_rqst *rqst;
>> 	struct nfs4_client *clp;
>>
>> +	clp = dl->dl_stid.sc_client;
>> +	/*
>> +	 * need to sync with courtesy client trying to reconnect using
>> +	 * the cl_cs_lock, nn->client_lock can not be used since this
>> +	 * function is called with the fl_lck held.
>> +	 */
>> +	spin_lock(&clp->cl_cs_lock);
>> +	if (test_bit(NFSD4_CLIENT_EXPIRED, &clp->cl_flags)) {
>> +		spin_unlock(&clp->cl_cs_lock);
>> +		return true;
>> +	}
>> +	if (test_bit(NFSD4_CLIENT_COURTESY, &clp->cl_flags)) {
>> +		set_bit(NFSD4_CLIENT_EXPIRED, &clp->cl_flags);
>> +		spin_unlock(&clp->cl_cs_lock);
>> +		return true;
>> +	}
>> +	spin_unlock(&clp->cl_cs_lock);
>> +
> Nit: Please add nfs4_check_and_expire_courtesy_client() in this patch
> instead of in 05/11.

That means nfs4_check_and_expire_courtesy_client is being called
in 05/11 but is not defined in 05/11. Is that ok?

-Dai

>
>
>> 	if (!i_am_nfsd())
>> 		return false;
>> 	rqst = kthread_data(current);
>> -- 
>> 2.9.5
>>
> --
> Chuck Lever
>
>
>