> -----Original Message-----
> From: Trond Myklebust <trondmy@xxxxxxxxxxxxxxx>
> Sent: 17 January 2020 17:24
> To: linux-nfs@xxxxxxxxxxxxxxx; rmilkowski@xxxxxxxxx
> Cc: anna.schumaker@xxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx;
> chuck.lever@xxxxxxxxxx
> Subject: Re: [PATCH v2] NFSv4: try lease recovery on NFS4ERR_EXPIRED
>
> On Fri, 2020-01-17 at 16:12 +0000, Robert Milkowski wrote:
> > Anyone please?
> >
> >
> > -----Original Message-----
> > From: Robert Milkowski <rmilkowski@xxxxxxxxx>
> > Sent: 08 January 2020 21:48
> > To: linux-nfs@xxxxxxxxxxxxxxx
> > Cc: 'Trond Myklebust' <trondmy@xxxxxxxxxxxxxxx>; 'Chuck Lever'
> > <chuck.lever@xxxxxxxxxx>; 'Anna Schumaker' <anna.schumaker@xxxxxxxxxx
> > >;
> > linux-kernel@xxxxxxxxxxxxxxx
> > Subject: [PATCH v2] NFSv4: try lease recovery on NFS4ERR_EXPIRED
> >
> > From: Robert Milkowski <rmilkowski@xxxxxxxxx>
> >
> > Currently, if an nfs server returns NFS4ERR_EXPIRED to open(), etc.
> > we return EIO to applications without even trying to recover.
> >
> > Fixes: 272289a3df72 ("NFSv4: nfs4_do_handle_exception() handle
> > revoke/expiry of a single stateid")
> > Signed-off-by: Robert Milkowski <rmilkowski@xxxxxxxxx>
> > ---
> > fs/nfs/nfs4proc.c | 4 ++++
> > 1 file changed, 4 insertions(+)
> >
> > diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c index
> > 76d3716..2478405
> > 100644
> > --- a/fs/nfs/nfs4proc.c
> > +++ b/fs/nfs/nfs4proc.c
> > @@ -481,6 +481,10 @@ static int nfs4_do_handle_exception(struct
> > nfs_server *server,
> > stateid);
> > goto wait_on_recovery;
> > }
> > + if (state == NULL) {
> > + nfs4_schedule_lease_recovery(clp);
> > + goto wait_on_recovery;
> > + }
> > /* Fall through */
> > case -NFS4ERR_OPENMODE:
> > if (inode) {
> > --
> > 1.8.3.1
> >
> >
>
> Does this apply to any case other than NFS4ERR_EXPIRED in the specific
> case of nfs4_do_open()? I can't see that it does. It looks to me as if
> the open recovery routines already have their own handling of this case.
I only observed the issue with open(). After further
review I think you are right and it only applies to nfs4_do_open().
>
> If so, why not just add it as a special case in the nfs4_do_open() error
> handling? Otherwise this patch will end up overriding other generic
> cases where we have an inode, but no open state.
>
Fair point.
So perhaps, few lines further instead of:
if (inode) {
...
if (state == NULL) {
break;
}
There should be:
if (inode) {
...
if (state == NULL) {
nfs4_schedule_lease_recovery(clp);
goto wait_on_recovery;
}
This way we know that inode cannot be null at this point, and it's a case where both inode and state are NULL.
This would be a little bit more general in case we reach this point.
But if you think it is better to move it to nfs4_do_open() then I've just tested the following patch:
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 76d3716..b7c4044 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -3187,6 +3187,11 @@ static struct nfs4_state *nfs4_do_open(struct inode *dir,
exception.retry = 1;
continue;
}
+ if (status == -NFS4ERR_EXPIRED) {
+ nfs4_schedule_lease_recovery(server->nfs_client);
+ exception.retry = 1;
+ continue;
+ }
if (status == -EAGAIN) {
/* We must have found a delegation */
exception.retry = 1;
Please let me know which way you want to proceed and I will submit an updated patch.
> Note that _nfs4_do_open() already waits for lease recovery, so we only
> need the call to nfs_schedule_lease_recovery().
>
Yep
--
Robert Milkowski
