Re: [PATCH] nfsd4: in-stateid seqid should start with 1

["J. Bruce Fields" <bfields@fieldses.org>]

On Wed, Aug 31, 2011 at 02:29:22PM -0700, Benny Halevy wrote:
> On 2011-08-31 14:19, J. Bruce Fields wrote:
> > On Wed, Aug 31, 2011 at 01:27:58PM -0700, Benny Halevy wrote:
> >> Don't we also need the following?
> >>
> >> As per RFC5661, skip zero seqid when wrapping around
> >> while updating a stateid.
> > 
> > Yep, done:
> > 
> > 	http://marc.info/?l=linux-nfs&m=131439774426154&w=2
> 
> yup, thanks!
> 
> > 
> > I need to send out my patches one at a time rather than fifteen at once
> > if I want people to read them....
> 
> My bad :-)

I'm gonna start inserting little "respond here if you read this far"
comments.

And actually I didn't read Casey's report carefully: he was just
complaining about delegation stateid's.  I don't think they matter much,
as their seqid field never changes, but may as well use the same as the
others.  And while we're there, make this uniform for v4.0 as well.

--b.

commit 80809fa40f8cfb3cf0bf006e3218bbd00584b38d
Author: J. Bruce Fields <bfields@redhat.com>
Date:   Wed Aug 31 15:47:21 2011 -0400

    nfsd4: make delegation stateid's seqid start at 1
    
    Thanks to Casey for reminding me that 5661 gives a special meaning to a
    value of 0 in the stateid's seqid field, so all stateid's should start
    out with si_generation 1.  We were doing that in the open and lock
    cases for minorversion 1, but not for the delegation stateid, and not
    for openstateid's with v4.0.
    
    It doesn't *really* matter much for v4.0 or for delegation stateid's
    (which never get the seqid field incremented), but we may as well do the
    same for all of them.
    
    Reported-by: Casey Bodley <cbodley@citi.umich.edu>
    Signed-off-by: J. Bruce Fields <bfields@redhat.com>

diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 49c3dd1..dc83ca1 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -251,7 +251,7 @@ alloc_init_deleg(struct nfs4_client *clp, struct nfs4_stateid *stp, struct svc_f
 	dp->dl_stateid.si_boot = boot_time;
 	dp->dl_stateid.si_stateownerid = current_delegid++;
 	dp->dl_stateid.si_fileid = 0;
-	dp->dl_stateid.si_generation = 0;
+	dp->dl_stateid.si_generation = 1;
 	fh_copy_shallow(&dp->dl_fh, &current_fh->fh_handle);
 	dp->dl_time = 0;
 	atomic_set(&dp->dl_count, 1);
@@ -2303,6 +2303,7 @@ init_stateid(struct nfs4_stateid *stp, struct nfs4_file *fp, struct nfsd4_open *
 	stp->st_stateid.si_boot = boot_time;
 	stp->st_stateid.si_stateownerid = oo->oo_owner.so_id;
 	stp->st_stateid.si_fileid = fp->fi_id;
+	/* note will be incremented before first return to client: */
 	stp->st_stateid.si_generation = 0;
 	stp->st_access_bmap = 0;
 	stp->st_deny_bmap = 0;
@@ -2893,7 +2894,6 @@ nfsd4_process_open2(struct svc_rqst *rqstp, struct svc_fh *current_fh, struct nf
 		status = nfs4_upgrade_open(rqstp, fp, current_fh, stp, open);
 		if (status)
 			goto out;
-		update_stateid(&stp->st_stateid);
 	} else {
 		status = nfs4_new_open(rqstp, &stp, fp, current_fh, open);
 		if (status)
@@ -2904,9 +2904,8 @@ nfsd4_process_open2(struct svc_rqst *rqstp, struct svc_fh *current_fh, struct nf
 			release_open_stateid(stp);
 			goto out;
 		}
-		if (nfsd4_has_session(&resp->cstate))
-			update_stateid(&stp->st_stateid);
 	}
+	update_stateid(&stp->st_stateid);
 	memcpy(&open->op_stateid, &stp->st_stateid, sizeof(stateid_t));
 
 	if (nfsd4_has_session(&resp->cstate))
@@ -3898,6 +3897,7 @@ alloc_init_lock_stateid(struct nfs4_lockowner *lo, struct nfs4_file *fp, struct
 	stp->st_stateid.si_boot = boot_time;
 	stp->st_stateid.si_stateownerid = lo->lo_owner.so_id;
 	stp->st_stateid.si_fileid = fp->fi_id;
+	/* note will be incremented before first return to client: */
 	stp->st_stateid.si_generation = 0;
 	stp->st_access_bmap = 0;
 	stp->st_deny_bmap = open_stp->st_deny_bmap;