[PATCH] kNFSdv4: Keep state to allow replays for 'close' to work.

From: NeilBrown <neilb@cse.unsw.edu.au>

From: "J. Bruce Fields" <bfields@fieldses.org>

From: Andros: Idea is to keep around a list of openowners recently released
by closes, and make sure they stay around long enough so that replays still
work.

fs/nfsd/nfs4state.c

@@ -136,12 +136,16 @@ static void release_file(struct nfs4_file *fp);
  *
  * client_lru holds client queue ordered by nfs4_client.cl_time
  * for lease renewal.
+ *
+ * close_lru holds (open) stateowner queue ordered by nfs4_stateowner.so_time
+ * for last close replay.
  */
 static struct list_head	conf_id_hashtbl[CLIENT_HASH_SIZE];
 static struct list_head	conf_str_hashtbl[CLIENT_HASH_SIZE];
 static struct list_head	unconf_str_hashtbl[CLIENT_HASH_SIZE];
 static struct list_head	unconf_id_hashtbl[CLIENT_HASH_SIZE];
 static struct list_head client_lru;
+static struct list_head close_lru;
 
 static inline void
 renew_client(struct nfs4_client *clp)
@@ -376,7 +380,6 @@ nfsd4_setclientid(struct svc_rqst *rqstp, struct nfsd4_setclientid *setclid)
 	unsigned int 		strhashval;
 	struct nfs4_client *	conf, * unconf, * new, * clp;
 	int 			status;
-	struct list_head *pos, *next;
 	
 	status = nfserr_inval;
 	if (!check_name(clname))
@@ -391,8 +394,7 @@ nfsd4_setclientid(struct svc_rqst *rqstp, struct nfsd4_setclientid *setclid)
 
 	conf = NULL;
 	nfs4_lock_state();
-	list_for_each_safe(pos, next, &conf_str_hashtbl[strhashval]) {
-		clp = list_entry(pos, struct nfs4_client, cl_strhash);
+	list_for_each_entry(clp, &conf_str_hashtbl[strhashval], cl_strhash) {
 		if (!cmp_name(&clp->cl_name, &clname))
 			continue;
 		/* 
@@ -422,8 +424,7 @@ nfsd4_setclientid(struct svc_rqst *rqstp, struct nfsd4_setclientid *setclid)
 		break;
 	}
 	unconf = NULL;
-	list_for_each_safe(pos, next, &unconf_str_hashtbl[strhashval]) {
-		clp = list_entry(pos, struct nfs4_client, cl_strhash);
+	list_for_each_entry(clp, &unconf_str_hashtbl[strhashval], cl_strhash) {
 		if (!cmp_name(&clp->cl_name, &clname))
 			continue;
 		/* cl_name match from a previous SETCLIENTID operation */
@@ -549,7 +550,6 @@ nfsd4_setclientid_confirm(struct svc_rqst *rqstp, struct nfsd4_setclientid_confi
 	struct nfs4_client *clp, *conf = NULL, *unconf = NULL;
 	nfs4_verifier confirm = setclientid_confirm->sc_confirm; 
 	clientid_t * clid = &setclientid_confirm->sc_clientid;
-	struct list_head *pos, *next;
 	int status;
 
 	status = nfserr_stale_clientid;
@@ -562,8 +562,7 @@ nfsd4_setclientid_confirm(struct svc_rqst *rqstp, struct nfsd4_setclientid_confi
 
 	idhashval = clientid_hashval(clid->cl_id);
 	nfs4_lock_state();
-	list_for_each_safe(pos, next, &conf_id_hashtbl[idhashval]) {
-		clp = list_entry(pos, struct nfs4_client, cl_idhash);
+	list_for_each_entry(clp, &conf_id_hashtbl[idhashval], cl_idhash) {
 		if (!cmp_clid(&clp->cl_clientid, clid))
 			continue;
 
@@ -582,8 +581,7 @@ nfsd4_setclientid_confirm(struct svc_rqst *rqstp, struct nfsd4_setclientid_confi
 		conf = clp;
 		break;
 	}
-	list_for_each_safe(pos, next, &unconf_id_hashtbl[idhashval]) {
-		clp = list_entry(pos, struct nfs4_client, cl_idhash);
+	list_for_each_entry(clp, &unconf_id_hashtbl[idhashval], cl_idhash) {
 		if (!cmp_clid(&clp->cl_clientid, clid))
 			continue;
 		status = nfserr_inval;
@@ -774,6 +772,8 @@ alloc_init_open_stateowner(unsigned int strhashval, struct nfs4_client *clp, str
 	INIT_LIST_HEAD(&sop->so_perclient);
 	INIT_LIST_HEAD(&sop->so_perfilestate);
 	INIT_LIST_HEAD(&sop->so_perlockowner);  /* not used */
+	INIT_LIST_HEAD(&sop->so_close_lru);
+	sop->so_time = 0;
 	list_add(&sop->so_idhash, &ownerid_hashtbl[idhashval]);
 	list_add(&sop->so_strhash, &ownerstr_hashtbl[strhashval]);
 	list_add(&sop->so_perclient, &clp->cl_perclient);
@@ -814,6 +814,7 @@ release_stateowner(struct nfs4_stateowner *sop)
 	list_del(&sop->so_strhash);
 	list_del(&sop->so_perclient);
 	list_del(&sop->so_perlockowner);
+	list_del(&sop->so_close_lru);
 	del_perclient++;
 	while (!list_empty(&sop->so_perfilestate)) {
 		stp = list_entry(sop->so_perfilestate.next, 
@@ -881,6 +882,19 @@ release_file(struct nfs4_file *fp)
 	kfree(fp);
 }	
 
+void
+move_to_close_lru(struct nfs4_stateowner *sop)
+{
+	dprintk("NFSD: move_to_close_lru nfs4_stateowner %p\n", sop);
+	/* remove stateowner from all other hash lists except perclient */
+	list_del_init(&sop->so_idhash);
+	list_del_init(&sop->so_strhash);
+	list_del_init(&sop->so_perlockowner);
+
+        list_add_tail(&sop->so_close_lru, &close_lru);
+        sop->so_time = get_seconds();
+}
+
 void
 release_state_owner(struct nfs4_stateid *stp, struct nfs4_stateowner **sopp,
 		int flag)
@@ -890,16 +904,13 @@ release_state_owner(struct nfs4_stateid *stp, struct nfs4_stateowner **sopp,
 
 	dprintk("NFSD: release_state_owner\n");
 	release_stateid(stp, flag);
-	/*
-	 * release unused nfs4_stateowners.
-	 * XXX will need to be placed  on an  open_stateid_lru list to be
+
+	/* place unused nfs4_stateowners on so_close_lru list to be
 	 * released by the laundromat service after the lease period
 	 * to enable us to handle CLOSE replay
 	 */
-	if (sop->so_confirmed && list_empty(&sop->so_perfilestate)) {
-		release_stateowner(sop);
-		*sopp = NULL;
-	}
+	if (sop->so_confirmed && list_empty(&sop->so_perfilestate))
+		move_to_close_lru(sop);
 	/* unused nfs4_file's are releseed. XXX slab cache? */
 	if (list_empty(&fp->fi_perfile)) {
 		release_file(fp);
@@ -916,11 +927,9 @@ cmp_owner_str(struct nfs4_stateowner *sop, struct xdr_netobj *owner, clientid_t
 /* search ownerstr_hashtbl[] for owner */
 static int
 find_openstateowner_str(unsigned int hashval, struct nfsd4_open *open, struct nfs4_stateowner **op) {
-	struct list_head *pos, *next;
 	struct nfs4_stateowner *local = NULL;
 
-	list_for_each_safe(pos, next, &ownerstr_hashtbl[hashval]) {
-		local = list_entry(pos, struct nfs4_stateowner, so_strhash);
+	list_for_each_entry(local, &ownerstr_hashtbl[hashval], so_strhash) {
 		if(!cmp_owner_str(local, &open->op_owner, &open->op_clientid)) 
 			continue;
 		*op = local;
@@ -933,12 +942,10 @@ find_openstateowner_str(unsigned int hashval, struct nfsd4_open *open, struct nf
 static int
 verify_clientid(struct nfs4_client **client, clientid_t *clid) {
 
-	struct list_head *pos, *next;
 	struct nfs4_client *clp;
 	unsigned int idhashval = clientid_hashval(clid->cl_id);
 
-	list_for_each_safe(pos, next, &conf_id_hashtbl[idhashval]) {
-		clp = list_entry(pos, struct nfs4_client, cl_idhash);
+	list_for_each_entry(clp, &conf_id_hashtbl[idhashval], cl_idhash) {
 		if (!cmp_clid(&clp->cl_clientid, clid))
 			continue;
 		*client = clp;
@@ -951,11 +958,9 @@ verify_clientid(struct nfs4_client **client, clientid_t *clid) {
 /* search file_hashtbl[] for file */
 static int
 find_file(unsigned int hashval, struct inode *ino, struct nfs4_file **fp) {
-	struct list_head *pos, *next;
 	struct nfs4_file *local = NULL;
 
-	list_for_each_safe(pos, next, &file_hashtbl[hashval]) {
-		local = list_entry(pos, struct nfs4_file, fi_hash);
+	list_for_each_entry(local, &file_hashtbl[hashval], fi_hash) {
 		if (local->fi_inode == ino) {
 			*fp = local;
 			return(1);
@@ -1011,15 +1016,13 @@ nfs4_share_conflict(struct svc_fh *current_fh, unsigned int deny_type)
 	unsigned int fi_hashval;
 	struct nfs4_file *fp;
 	struct nfs4_stateid *stp;
-	struct list_head *pos, *next;
 
 	dprintk("NFSD: nfs4_share_conflict\n");
 
 	fi_hashval = file_hashval(ino);
 	if (find_file(fi_hashval, ino, &fp)) {
 	/* Search for conflicting share reservations */
-		list_for_each_safe(pos, next, &fp->fi_perfile) {
-			stp = list_entry(pos, struct nfs4_stateid, st_perfile);
+		list_for_each_entry(stp, &fp->fi_perfile, st_perfile) {
 			if (test_bit(deny_type, &stp->st_deny_bmap) ||
 			    test_bit(NFS4_SHARE_DENY_BOTH, &stp->st_deny_bmap))
 				return nfserr_share_denied;
@@ -1154,7 +1157,6 @@ nfsd4_process_open2(struct svc_rqst *rqstp, struct svc_fh *current_fh, struct nf
 	struct nfs4_file *fp;
 	struct inode *ino;
 	unsigned int fi_hashval;
-	struct list_head *pos, *next;
 	struct nfs4_stateid *stq, *stp = NULL;
 	int status;
 
@@ -1173,8 +1175,7 @@ nfsd4_process_open2(struct svc_rqst *rqstp, struct svc_fh *current_fh, struct nf
 	if (find_file(fi_hashval, ino, &fp)) {
 		/* Search for conflicting share reservations */
 		status = nfserr_share_denied;
-		list_for_each_safe(pos, next, &fp->fi_perfile) {
-		stq = list_entry(pos, struct nfs4_stateid, st_perfile);
+		list_for_each_entry(stq, &fp->fi_perfile, st_perfile) {
 			if(stq->st_stateowner == sop) {
 				stp = stq;
 				continue;
@@ -1274,7 +1275,6 @@ int
 nfsd4_renew(clientid_t *clid)
 {
 	struct nfs4_client *clp;
-	struct list_head *pos, *next;
 	unsigned int idhashval;
 	int status;
 
@@ -1286,15 +1286,13 @@ nfsd4_renew(clientid_t *clid)
 		goto out;
 	status = nfs_ok;
 	idhashval = clientid_hashval(clid->cl_id);
-	list_for_each_safe(pos, next, &conf_id_hashtbl[idhashval]) {
-		clp = list_entry(pos, struct nfs4_client, cl_idhash);
+	list_for_each_entry(clp, &conf_id_hashtbl[idhashval], cl_idhash) {
 		if (!cmp_clid(&clp->cl_clientid, clid))
 			continue;
 		renew_client(clp);
 		goto out;
 	}
-	list_for_each_safe(pos, next, &unconf_id_hashtbl[idhashval]) {
-		clp = list_entry(pos, struct nfs4_client, cl_idhash);
+	list_for_each_entry(clp, &unconf_id_hashtbl[idhashval], cl_idhash) {
 		if (!cmp_clid(&clp->cl_clientid, clid))
 			continue;
 		renew_client(clp);
@@ -1316,9 +1314,11 @@ time_t
 nfs4_laundromat(void)
 {
 	struct nfs4_client *clp;
+	struct nfs4_stateowner *sop;
 	struct list_head *pos, *next;
 	time_t cutoff = get_seconds() - NFSD_LEASE_TIME;
-	time_t t, return_val = NFSD_LEASE_TIME;
+	time_t t, clientid_val = NFSD_LEASE_TIME;
+	time_t u, close_val = NFSD_LEASE_TIME;
 
 	nfs4_lock_state();
 
@@ -1327,18 +1327,30 @@ nfs4_laundromat(void)
 		clp = list_entry(pos, struct nfs4_client, cl_lru);
 		if (time_after((unsigned long)clp->cl_time, (unsigned long)cutoff)) {
 			t = clp->cl_time - cutoff;
-			if (return_val > t)
-				return_val = t;
+			if (clientid_val > t)
+				clientid_val = t;
 			break;
 		}
 		dprintk("NFSD: purging unused client (clientid %08x)\n",
 			clp->cl_clientid.cl_id);
 		expire_client(clp);
 	}
-	if (return_val < NFSD_LAUNDROMAT_MINTIMEOUT)
-		return_val = NFSD_LAUNDROMAT_MINTIMEOUT;
+	list_for_each_safe(pos, next, &close_lru) {
+		sop = list_entry(pos, struct nfs4_stateowner, so_close_lru);
+		if (time_after((unsigned long)sop->so_time, (unsigned long)cutoff)) {
+			u = sop->so_time - cutoff;
+			if (close_val > u)
+				close_val = u;
+			break;
+		}
+		dprintk("NFSD: purging unused open stateowner (so_id %d)\n",
+			sop->so_id);
+		release_stateowner(sop);
+	}
+	if (clientid_val < NFSD_LAUNDROMAT_MINTIMEOUT)
+		clientid_val = NFSD_LAUNDROMAT_MINTIMEOUT;
 	nfs4_unlock_state();
-	return return_val;
+	return clientid_val;
 }
 
 void
@@ -1351,17 +1363,19 @@ laundromat_main(void *not_used)
 	schedule_delayed_work(&laundromat_work, t*HZ);
 }
 
-/* search ownerid_hashtbl[] for stateid owner (stateid->si_stateownerid) */
+/* search ownerid_hashtbl[] and close_lru for stateid owner
+ * (stateid->si_stateownerid)
+ */
 struct nfs4_stateowner *
-find_openstateowner_id(u32 st_id) {
-	struct list_head *pos, *next;
+find_openstateowner_id(u32 st_id, int flags) {
 	struct nfs4_stateowner *local = NULL;
-	unsigned int hashval = ownerid_hashval(st_id);
 
-	list_for_each_safe(pos, next, &ownerid_hashtbl[hashval]) {
-		local = list_entry(pos, struct nfs4_stateowner, so_idhash);
-		if(local->so_id == st_id)
-			return local;
+	dprintk("NFSD: find_openstateowner_id %d\n", st_id);
+	if (flags & CLOSE_STATE) {
+		list_for_each_entry(local, &close_lru, so_close_lru) {
+			if(local->so_id == st_id)
+				return local;
+		}
 	}
 	return NULL;
 }
@@ -1547,11 +1561,12 @@ nfs4_preprocess_seqid_op(struct svc_fh *current_fh, u32 seqid, stateid_t *statei
 	* starting by trying to look up the stateowner.
 	* If stateowner is not found - stateid is bad.
 	*/
-	if (!(sop = find_openstateowner_id(stateid->si_stateownerid))) {
+	if (!(sop = find_openstateowner_id(stateid->si_stateownerid, flags))) {
 		printk("NFSD: preprocess_seqid_op: no stateowner or nfs4_stateid!\n");
 		status = nfserr_bad_stateid;
 		goto out;
 	}
+	*sopp = sop;
 
 check_replay:
 	if (seqid == sop->so_seqid) {
@@ -1690,9 +1705,10 @@ nfsd4_close(struct svc_rqst *rqstp, struct svc_fh *current_fh, struct nfsd4_clos
 			current_fh->fh_dentry->d_name.name);
 
 	nfs4_lock_state();
+	/* check close_lru for replay */
 	if ((status = nfs4_preprocess_seqid_op(current_fh, close->cl_seqid, 
 					&close->cl_stateid, 
-					CHECK_FH | OPEN_STATE, 
+					CHECK_FH | OPEN_STATE | CLOSE_STATE,
 					&close->cl_stateowner, &stp, NULL)))
 		goto out; 
 	/*
@@ -1729,7 +1745,6 @@ static struct list_head lockstateid_hashtbl[STATEID_HASH_SIZE];
 struct nfs4_stateid *
 find_stateid(stateid_t *stid, int flags)
 {
-	struct list_head *pos, *next;
 	struct nfs4_stateid *local = NULL;
 	u32 st_id = stid->si_stateownerid;
 	u32 f_id = stid->si_fileid;
@@ -1738,8 +1753,7 @@ find_stateid(stateid_t *stid, int flags)
 	dprintk("NFSD: find_stateid flags 0x%x\n",flags);
 	if ((flags & LOCK_STATE) || (flags & RDWR_STATE)) {
 		hashval = stateid_hashval(st_id, f_id);
-		list_for_each_safe(pos, next, &lockstateid_hashtbl[hashval]) {
-			local = list_entry(pos, struct nfs4_stateid, st_hash);
+		list_for_each_entry(local, &lockstateid_hashtbl[hashval], st_hash) {
 			if((local->st_stateid.si_stateownerid == st_id) &&
 			   (local->st_stateid.si_fileid == f_id))
 				return local;
@@ -1747,8 +1761,7 @@ find_stateid(stateid_t *stid, int flags)
 	} 
 	if ((flags & OPEN_STATE) || (flags & RDWR_STATE)) {
 		hashval = stateid_hashval(st_id, f_id);
-		list_for_each_safe(pos, next, &stateid_hashtbl[hashval]) {
-			local = list_entry(pos, struct nfs4_stateid, st_hash);
+		list_for_each_entry(local, &stateid_hashtbl[hashval], st_hash) {
 			if((local->st_stateid.si_stateownerid == st_id) &&
 			   (local->st_stateid.si_fileid == f_id))
 				return local;
@@ -1779,14 +1792,12 @@ nfs4_transform_lock_offset(struct file_lock *lock)
 int
 nfs4_verify_lock_stateowner(struct nfs4_stateowner *sop, unsigned int hashval)
 {
-	struct list_head *pos, *next;
 	struct nfs4_stateowner *local = NULL;
 	int status = 0;
 			        
 	if (hashval >= LOCK_HASH_SIZE)
 		goto out;
-	list_for_each_safe(pos, next, &lock_ownerid_hashtbl[hashval]) {
-		local = list_entry(pos, struct nfs4_stateowner, so_idhash);
+	list_for_each_entry(local, &lock_ownerid_hashtbl[hashval], so_idhash) {
 		if (local == sop) {
 			status = 1;
 			goto out;
@@ -1817,11 +1828,9 @@ nfs4_set_lock_denied(struct file_lock *fl, struct nfsd4_lock_denied *deny)
 
 static int
 find_lockstateowner_str(unsigned int hashval, struct xdr_netobj *owner, clientid_t *clid, struct nfs4_stateowner **op) {
-	struct list_head *pos, *next;
 	struct nfs4_stateowner *local = NULL;
 
-	list_for_each_safe(pos, next, &lock_ownerstr_hashtbl[hashval]) {
-		local = list_entry(pos, struct nfs4_stateowner, so_strhash);
+	list_for_each_entry(local, &lock_ownerstr_hashtbl[hashval], so_strhash) {
 		if(!cmp_owner_str(local, owner, clid)) 
 			continue;
 		*op = local;
@@ -1854,6 +1863,8 @@ alloc_init_lock_stateowner(unsigned int strhashval, struct nfs4_client *clp, str
 	INIT_LIST_HEAD(&sop->so_perclient);
 	INIT_LIST_HEAD(&sop->so_perfilestate);
 	INIT_LIST_HEAD(&sop->so_perlockowner);
+	INIT_LIST_HEAD(&sop->so_close_lru); /* not used */
+	sop->so_time = 0;
 	list_add(&sop->so_idhash, &lock_ownerid_hashtbl[idhashval]);
 	list_add(&sop->so_strhash, &lock_ownerstr_hashtbl[strhashval]);
 	list_add(&sop->so_perclient, &clp->cl_perclient);
@@ -2265,7 +2276,6 @@ int
 nfsd4_release_lockowner(struct svc_rqst *rqstp, struct nfsd4_release_lockowner *rlockowner)
 {
 	clientid_t *clid = &rlockowner->rl_clientid;
-	struct list_head *pos, *next;
 	struct nfs4_stateowner *local = NULL;
 	struct xdr_netobj *owner = &rlockowner->rl_owner;
 	int status, i;
@@ -2286,9 +2296,7 @@ nfsd4_release_lockowner(struct svc_rqst *rqstp, struct nfsd4_release_lockowner *
 	/* find the lockowner */
         status = nfs_ok;
 	for (i=0; i < LOCK_HASH_SIZE; i++) {
-		list_for_each_safe(pos, next, &lock_ownerstr_hashtbl[i]) {
-			local = list_entry(pos, struct nfs4_stateowner,
-						so_strhash);
+		list_for_each_entry(local, &lock_ownerstr_hashtbl[i], so_strhash) {
 			if(cmp_owner_str(local, owner, clid))
 				break;
 		}
@@ -2299,9 +2307,7 @@ nfsd4_release_lockowner(struct svc_rqst *rqstp, struct nfsd4_release_lockowner *
 		/* check for any locks held by any stateid associated with the
 		 * (lock) stateowner */
 		status = nfserr_locks_held;
-		list_for_each_safe(pos, next, &local->so_perfilestate) {
-			stp = list_entry(pos, struct nfs4_stateid,
-					                    st_perfilestate);
+		list_for_each_entry(stp, &local->so_perfilestate, st_perfilestate) {
 			if(stp->st_vfs_set) {
 				if (check_for_locks(&stp->st_vfs_file, local))
 					goto out;
@@ -2351,6 +2357,7 @@ nfs4_state_init(void)
 	memset(&zerostateid, 0, sizeof(stateid_t));
 	memset(&onestateid, ~0, sizeof(stateid_t));
 
+	INIT_LIST_HEAD(&close_lru);
 	INIT_LIST_HEAD(&client_lru);
 	init_MUTEX(&client_sema);
 	boot_time = get_seconds();

include/linux/nfsd/state.h

@@ -132,6 +132,9 @@ struct nfs4_replay {
 *         release a stateowner.
 *    so_perlockowner: (open) nfs4_stateid->st_perlockowner entry - used when
 *         close is called to reap associated byte-range locks
+*    so_close_lru: (open) stateowner is placed on this list instead of being
+*         reaped (when so_perfilestate is empty) to hold the last close replay.
+*         reaped by laundramat thread after lease period.
 */
 struct nfs4_stateowner {
 	struct list_head        so_idhash;   /* hash by so_id */
@@ -139,6 +142,8 @@ struct nfs4_stateowner {
 	struct list_head        so_perclient; /* nfs4_client->cl_perclient */
 	struct list_head        so_perfilestate; /* list: nfs4_stateid */
 	struct list_head        so_perlockowner; /* nfs4_stateid->st_perlockowner */
+	struct list_head	so_close_lru; /* tail queue */
+	time_t			so_time; /* time of placement on so_close_lru */
 	int			so_is_open_owner; /* 1=openowner,0=lockowner */
 	u32                     so_id;
 	struct nfs4_client *    so_client;
@@ -194,6 +199,7 @@ struct nfs4_stateid {
 #define OPEN_STATE              0x00000004
 #define LOCK_STATE              0x00000008
 #define RDWR_STATE              0x00000010
+#define CLOSE_STATE             0x00000020
 
 #define seqid_mutating_err(err)                       \
 	(((err) != nfserr_stale_clientid) &&    \