nfsd4: hash closed stateid's like any other

Look up closed stateid's in the stateid hash like any other stateid
rather than searching the close lru.

This is simpler, and fixes a bug: currently we handle only the case of a
close that is the last close for a given stateowner, but not the case of
a close for a stateowner that still has active opens on other files.
Thus in a case like:

	open(owner, file1)
	open(owner, file2)
	close(owner, file2)
	close(owner, file2)

the final close won't be recognized as a retransmission.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>

1 files changed, 53 insertions, 48 deletions

diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 922f47dd0d74..e5cba833613f 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -406,7 +406,6 @@ static int nfs4_access_to_omode(u32 access)
 
 static void unhash_generic_stateid(struct nfs4_ol_stateid *stp)
 {
-        list_del(&stp->st_stid.sc_hash);
         list_del(&stp->st_perfile);
         list_del(&stp->st_perstateowner);
 }
@@ -437,6 +436,7 @@ static void release_lock_stateid(struct nfs4_ol_stateid *stp)
         struct file *file;
 
         unhash_generic_stateid(stp);
+        list_del(&stp->st_stid.sc_hash);
         file = find_any_file(stp->st_file);
         if (file)
                 locks_remove_posix(file, (fl_owner_t)lockowner(stp->st_stateowner));
@@ -485,6 +485,7 @@ static void unhash_open_stateid(struct nfs4_ol_stateid *stp)
 static void release_open_stateid(struct nfs4_ol_stateid *stp)
 {
         unhash_open_stateid(stp);
+        list_del(&stp->st_stid.sc_hash);
         free_generic_stateid(stp);
 }
 
@@ -501,12 +502,22 @@ static void unhash_openowner(struct nfs4_openowner *oo)
         }
 }
 
+static void release_last_closed_stateid(struct nfs4_openowner *oo)
+{
+        struct nfs4_ol_stateid *s = oo->oo_last_closed_stid;
+
+        if (s) {
+                list_del_init(&s->st_stid.sc_hash);
+                free_generic_stateid(s);
+                oo->oo_last_closed_stid = NULL;
+        }
+}
+
 static void release_openowner(struct nfs4_openowner *oo)
 {
         unhash_openowner(oo);
         list_del(&oo->oo_close_lru);
-        if (oo->oo_last_closed_stid)
-                free_generic_stateid(oo->oo_last_closed_stid);
+        release_last_closed_stateid(oo);
         nfs4_free_openowner(oo);
 }
 
@@ -3099,23 +3110,11 @@ laundromat_main(struct work_struct *not_used)
         queue_delayed_work(laundry_wq, &laundromat_work, t*HZ);
 }
 
-static struct nfs4_openowner * search_close_lru(stateid_t *s)
-{
-        struct nfs4_openowner *local;
-        struct nfs4_ol_stateid *os;
-
-        list_for_each_entry(local, &close_lru, oo_close_lru) {
-                os = local->oo_last_closed_stid;
-                if (same_stateid(&os->st_stid.sc_stateid, s))
-                        return local;
-        }
-        return NULL;
-}
-
-static inline int
-nfs4_check_fh(struct svc_fh *fhp, struct nfs4_ol_stateid *stp)
+static inline __be32 nfs4_check_fh(struct svc_fh *fhp, struct nfs4_ol_stateid *stp)
 {
-        return fhp->fh_dentry->d_inode != stp->st_file->fi_inode;
+        if (fhp->fh_dentry->d_inode != stp->st_file->fi_inode)
+                return nfserr_bad_stateid;
+        return nfs_ok;
 }
 
 static int
@@ -3283,7 +3282,8 @@ nfs4_preprocess_stateid_op(struct nfsd4_compound_state *cstate,
         status = check_stateid_generation(stateid, &s->sc_stateid, nfsd4_has_session(cstate));
         if (status)
                 goto out;
-        if (s->sc_type == NFS4_DELEG_STID) {
+        switch (s->sc_type) {
+        case NFS4_DELEG_STID:
                 dp = delegstateid(s);
                 status = nfs4_check_delegmode(dp, flags);
                 if (status)
@@ -3293,10 +3293,12 @@ nfs4_preprocess_stateid_op(struct nfsd4_compound_state *cstate,
                         *filpp = dp->dl_file->fi_deleg_file;
                         BUG_ON(!*filpp);
                 }
-        } else { /* open or lock stateid */
+                break;
+        case NFS4_OPEN_STID:
+        case NFS4_LOCK_STID:
                 stp = openlockstateid(s);
-                status = nfserr_bad_stateid;
-                if (nfs4_check_fh(current_fh, stp))
+                status = nfs4_check_fh(current_fh, stp);
+                if (status)
                         goto out;
                 if (stp->st_stateowner->so_is_open_owner
                     && !(openowner(stp->st_stateowner)->oo_flags & NFS4_OO_CONFIRMED))
@@ -3311,6 +3313,9 @@ nfs4_preprocess_stateid_op(struct nfsd4_compound_state *cstate,
                         else
                                 *filpp = find_writeable_file(stp->st_file);
                 }
+                break;
+        default:
+                return nfserr_bad_stateid;
         }
         status = nfs_ok;
 out:
@@ -3362,6 +3367,9 @@ nfsd4_free_stateid(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
                         ret = nfsd4_free_lock_stateid(openlockstateid(s));
                 else
                         ret = nfserr_locks_held;
+                break;
+        default:
+                ret = nfserr_bad_stateid;
         }
 out:
         nfs4_unlock_state();
@@ -3390,12 +3398,19 @@ static __be32 nfs4_seqid_op_checks(struct nfsd4_compound_state *cstate, stateid_
         struct nfs4_stateowner *sop = stp->st_stateowner;
         __be32 status;
 
-        if (nfs4_check_fh(current_fh, stp))
-                return nfserr_bad_stateid;
         status = nfsd4_check_seqid(cstate, sop, seqid);
         if (status)
                 return status;
-        return check_stateid_generation(stateid, &stp->st_stid.sc_stateid, nfsd4_has_session(cstate));
+        if (stp->st_stid.sc_type == NFS4_CLOSED_STID)
+                /*
+                 * "Closed" stateid's exist *only* to return
+                 * nfserr_replay_me from the previous step.
+                 */
+                return nfserr_bad_stateid;
+        status = check_stateid_generation(stateid, &stp->st_stid.sc_stateid, nfsd4_has_session(cstate));
+        if (status)
+                return status;
+        return nfs4_check_fh(current_fh, stp);
 }
 
 /* 
@@ -3564,8 +3579,13 @@ void nfsd4_purge_closed_stateid(struct nfs4_stateowner *so)
                 return;
         }
         oo->oo_flags &= ~NFS4_OO_PURGE_CLOSE;
-        free_generic_stateid(oo->oo_last_closed_stid);
-        oo->oo_last_closed_stid = NULL;
+        release_last_closed_stateid(oo);
+}
+
+static void nfsd4_close_open_stateid(struct nfs4_ol_stateid *s)
+{
+        unhash_open_stateid(s);
+        s->st_stid.sc_type = NFS4_CLOSED_STID;
 }
 
 /*
@@ -3584,24 +3604,10 @@ nfsd4_close(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
                         cstate->current_fh.fh_dentry->d_name.name);
 
         nfs4_lock_state();
-        /* check close_lru for replay */
-        status = nfs4_preprocess_confirmed_seqid_op(cstate, close->cl_seqid,
-                                        &close->cl_stateid, &stp);
-        if (stp == NULL && status == nfserr_expired) {
-                /*
-                 * Also, we should make sure this isn't just the result of
-                 * a replayed close:
-                 */
-                oo = search_close_lru(&close->cl_stateid);
-                /* It's not stale; let's assume it's expired: */
-                if (oo == NULL)
-                        goto out;
-                cstate->replay_owner = &oo->oo_owner;
-                status = nfsd4_check_seqid(cstate, &oo->oo_owner, close->cl_seqid);
-                if (status)
-                        goto out;
-                status = nfserr_bad_seqid;
-        }
+        status = nfs4_preprocess_seqid_op(cstate, close->cl_seqid,
+                                        &close->cl_stateid,
+                                        NFS4_OPEN_STID|NFS4_CLOSED_STID,
+                                        &stp);
         if (status)
                 goto out; 
         oo = openowner(stp->st_stateowner);
@@ -3609,9 +3615,8 @@ nfsd4_close(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
         update_stateid(&stp->st_stid.sc_stateid);
         memcpy(&close->cl_stateid, &stp->st_stid.sc_stateid, sizeof(stateid_t));
 
-        /* unhash_open_stateid() calls nfsd_close() if needed */
+        nfsd4_close_open_stateid(stp);
         oo->oo_last_closed_stid = stp;
-        unhash_open_stateid(stp);
 
         /* place unused nfs4_stateowners on so_close_lru list to be
          * released by the laundromat service after the lease period