CB_RECALL fixes

CB_RECALL fixes

[Christoph Hellwig]

First one fixes error handling in nfsd4_cb_recall_done, second is a fix from
Benny in the old pnfs tree which applies to restarted delegation recalls
as well.

[PATCH 1/2] nfsd: fix nfsd4_cb_recall_done error handling

[Christoph Hellwig]

For any error that is not EBADHANDLE or NFS4ERR_BAD_STATEID,
nfsd4_cb_recall_done first marks the connection down, then
retries until dl_retries hits zero, then marks the connection down
again and sets cb_done.  This changes the code to only retry
for EBADHANDLE or NFS4ERR_BAD_STATEID, and factors setting
cb_done into a single point in the function.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 fs/nfsd/nfs4callback.c | 17 +++++++----------
 1 file changed, 7 insertions(+), 10 deletions(-)

diff --git a/fs/nfsd/nfs4callback.c b/fs/nfsd/nfs4callback.c
index e0be57b..795e218 100644
--- a/fs/nfsd/nfs4callback.c
+++ b/fs/nfsd/nfs4callback.c
@@ -874,24 +874,21 @@ static void nfsd4_cb_recall_done(struct rpc_task *task, void *calldata)
 		return;
 	switch (task->tk_status) {
 	case 0:
-		cb->cb_done = true;
-		return;
+		break;
 	case -EBADHANDLE:
 	case -NFS4ERR_BAD_STATEID:
 		/* Race: client probably got cb_recall
 		 * before open reply granting delegation */
-		break;
+		if (dp->dl_retries--) {
+			rpc_delay(task, 2*HZ);
+			task->tk_status = 0;
+			rpc_restart_call_prepare(task);
+			return;
+		}
 	default:
 		/* Network partition? */
 		nfsd4_mark_cb_down(clp, task->tk_status);
 	}
-	if (dp->dl_retries--) {
-		rpc_delay(task, 2*HZ);
-		task->tk_status = 0;
-		rpc_restart_call_prepare(task);
-		return;
-	}
-	nfsd4_mark_cb_down(clp, task->tk_status);
 	cb->cb_done = true;
 }
 
-- 
1.9.1

[PATCH 2/2] nfsd: do not clear rpc_resp in nfsd4_cb_done_sequence

[Christoph Hellwig]

From: Benny Halevy <bhalevy@panasas.com>

This is incorrect when a callback is has to be restarted, in which case
the XDR decoding of the second iteration will see a NULL cb argument.

[hch: updated description]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 fs/nfsd/nfs4callback.c | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/fs/nfsd/nfs4callback.c b/fs/nfsd/nfs4callback.c
index 795e218..fc07084 100644
--- a/fs/nfsd/nfs4callback.c
+++ b/fs/nfsd/nfs4callback.c
@@ -847,9 +847,6 @@ static void nfsd4_cb_done(struct rpc_task *task, void *calldata)
 		rpc_wake_up_next(&clp->cl_cb_waitq);
 		dprintk("%s: freed slot, new seqid=%d\n", __func__,
 			clp->cl_cb_session->se_cb_seq_nr);
-
-		/* We're done looking into the sequence information */
-		task->tk_msg.rpc_resp = NULL;
 	}
 }
 
-- 
1.9.1

Re: CB_RECALL fixes

[J. Bruce Fields]

On Tue, Sep 23, 2014 at 08:58:47AM +0200, Christoph Hellwig wrote:
> First one fixes error handling in nfsd4_cb_recall_done, second is a fix from
> Benny in the old pnfs tree which applies to restarted delegation recalls
> as well.

Thanks, applying both for 3.18.

(Assuming that's what you intended.  When you want nfsd patches applied,
could you do an explicit To: bfields@fieldses.org ?)

--b.

Re: CB_RECALL fixes

[Christoph Hellwig]

On Tue, Sep 23, 2014 at 03:33:02PM -0400, J. Bruce Fields wrote:
> On Tue, Sep 23, 2014 at 08:58:47AM +0200, Christoph Hellwig wrote:
> > First one fixes error handling in nfsd4_cb_recall_done, second is a fix from
> > Benny in the old pnfs tree which applies to restarted delegation recalls
> > as well.
> 
> Thanks, applying both for 3.18.
> 
> (Assuming that's what you intended.  When you want nfsd patches applied,
> could you do an explicit To: bfields@fieldses.org ?)

Yes, and I'll send it to you with cc to linux-nfs next time, sorry.