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| author | Trond Myklebust <trond.myklebust@primarydata.com> | 2014-12-19 19:22:28 +0300 |
|---|---|---|
| committer | Trond Myklebust <trond.myklebust@primarydata.com> | 2015-01-25 02:46:51 +0300 |
| commit | cf6726e2ee387b0eff303628eaa0beaf36a1aeb4 (patch) | |
| tree | e689a97ec219956e42b2475beb794adfb5c6f4b1 /fs/nfs/delegation.c | |
| parent | 89f0ff386cb1ebca0da7940d05bf609bc86f3972 (diff) | |
| download | linux-cf6726e2ee387b0eff303628eaa0beaf36a1aeb4.tar.xz | |
NFSv4: Deal with atomic upgrades of an existing delegation
Ensure that we deal correctly with the case where the server sends us a
newer instance of the same delegation. If the stateids match, but the
sequence numbers differ, then treat the new delegation as if it were
an atomic upgrade.
Signed-off-by: Trond Myklebust <Trond.Myklebust@primarydata.com>
Diffstat (limited to 'fs/nfs/delegation.c')
| -rw-r--r-- | fs/nfs/delegation.c | 20 |
1 files changed, 17 insertions, 3 deletions
diff --git a/fs/nfs/delegation.c b/fs/nfs/delegation.c index 7f3f60641344..16b754ee0d09 100644 --- a/fs/nfs/delegation.c +++ b/fs/nfs/delegation.c @@ -301,6 +301,17 @@ nfs_inode_detach_delegation(struct inode *inode) return nfs_detach_delegation(nfsi, delegation, server); } +static void +nfs_update_inplace_delegation(struct nfs_delegation *delegation, + const struct nfs_delegation *update) +{ + if (nfs4_stateid_is_newer(&update->stateid, &delegation->stateid)) { + delegation->stateid.seqid = update->stateid.seqid; + smp_wmb(); + delegation->type = update->type; + } +} + /** * nfs_inode_set_delegation - set up a delegation on an inode * @inode: inode to which delegation applies @@ -334,9 +345,12 @@ int nfs_inode_set_delegation(struct inode *inode, struct rpc_cred *cred, struct old_delegation = rcu_dereference_protected(nfsi->delegation, lockdep_is_held(&clp->cl_lock)); if (old_delegation != NULL) { - if (nfs4_stateid_match(&delegation->stateid, - &old_delegation->stateid) && - delegation->type == old_delegation->type) { + /* Is this an update of the existing delegation? */ + if (nfs4_stateid_match_other(&old_delegation->stateid, + &delegation->stateid)) { + nfs_update_inplace_delegation(old_delegation, + delegation); + nfsi->delegation_state = old_delegation->type; goto out; } /* |