nfs/nlm: procedures for PC clients

*  This change introduces four NLMv4 procedures:

   NM_LOCK, SHARE, UNSHARE and FREE_ALL.

   These are used by PC clients (windows/dos) to control access
   to files.

   1. NM_LOCK: this lock is not monitored by statd.

   2. SHARE: A share reservation is a lock on the whole file
      that is taken whenever a file is opened on windows clients.
      This has ACCESS (N, R, W, RW) and DENY MODE (N, R, W, RW).
        ACCESS:    mode of access requested by the client;
        DENY MODE: what the requesting client wants to
                   deny other clients.

   3. UNSHARE: remove a share reservation obtained by SHARE.
      Called while closing a file.

   4. FREE_ALL: remove all share reservations and locks,
      both monitored and unmonitored, of the calling client.

*  lock and nm_lock use a common function with only
   a flag conveying whether or not to monitor a lock.

*  NOTES:
   1. SHARE reservations are not STACK_WIND'd to subsequent xlators.
      These are maintained in-memory in the nfs xlator.

   2. Consequently, for SHARE reservations to work effectively,
      all PC clients  *must* mount from the same gNfs server.
      Not doing so will result in different servers maintaining
      separate SHARE reservations which will not be enforced
      for obvious reasons.

Change-Id: Id4f22670a94ed58691a6a7f4c80aa8c11421a277
BUG: 800287
Signed-off-by: Rajesh Amaravathi <rajesh@redhat.com>
Reviewed-on: http://review.gluster.com/3212
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Krishna Srinivas <krishna@gluster.com>

10 files changed, 661 insertions, 37 deletions

diff --git a/rpc/xdr/src/msg-nfs3.c b/rpc/xdr/src/msg-nfs3.c
index f800b3128fa..8078f23f097 100644
--- a/rpc/xdr/src/msg-nfs3.c
+++ b/rpc/xdr/src/msg-nfs3.c
@@ -517,6 +517,20 @@ xdr_to_nlm4_unlockargs (struct iovec inmsg, nlm4_unlockargs *args)
 }
 
 ssize_t
+xdr_to_nlm4_shareargs (struct iovec inmsg, nlm4_shareargs *args)
+{
+        return xdr_to_generic (inmsg, (void*)args,
+                               (xdrproc_t)xdr_nlm4_shareargs);
+}
+
+ssize_t
+xdr_serialize_nlm4_shareres (struct iovec outmsg, nlm4_shareres *res)
+{
+        return xdr_serialize_generic (outmsg, (void *)res,
+                                      (xdrproc_t)xdr_nlm4_shareres);
+}
+
+ssize_t
 xdr_serialize_nlm4_testargs (struct iovec outmsg, nlm4_testargs *args)
 {
         return xdr_serialize_generic (outmsg, (void*)args,
@@ -530,3 +544,9 @@ xdr_to_nlm4_res (struct iovec inmsg, nlm4_res *args)
                                (xdrproc_t)xdr_nlm4_res);
 }
 
+ssize_t
+xdr_to_nlm4_freeallargs (struct iovec inmsg, nlm4_freeallargs *args)
+{
+        return xdr_to_generic (inmsg, (void*)args,
+                               (xdrproc_t)xdr_nlm4_freeallargs);
+}
diff --git a/rpc/xdr/src/msg-nfs3.h b/rpc/xdr/src/msg-nfs3.h
index 1310e02f897..701df300a6e 100644
--- a/rpc/xdr/src/msg-nfs3.h
+++ b/rpc/xdr/src/msg-nfs3.h
@@ -203,9 +203,18 @@ extern ssize_t
 xdr_to_nlm4_unlockargs (struct iovec inmsg, nlm4_unlockargs *args);
 
 extern ssize_t
+xdr_to_nlm4_shareargs (struct iovec inmsg, nlm4_shareargs *args);
+
+extern ssize_t
+xdr_serialize_nlm4_shareres (struct iovec outmsg, nlm4_shareres *res);
+
+extern ssize_t
 xdr_serialize_nlm4_testargs (struct iovec outmsg, nlm4_testargs *args);
 
 extern ssize_t
 xdr_to_nlm4_res (struct iovec inmsg, nlm4_res *args);
 
+extern ssize_t
+xdr_to_nlm4_freeallargs (struct iovec inmsg, nlm4_freeallargs *args);
+
 #endif
diff --git a/rpc/xdr/src/nlm4-xdr.c b/rpc/xdr/src/nlm4-xdr.c
index b41fbb15cac..4cf6a51e8fd 100644
--- a/rpc/xdr/src/nlm4-xdr.c
+++ b/rpc/xdr/src/nlm4-xdr.c
@@ -228,6 +228,17 @@ xdr_nlm4_shareres (XDR *xdrs, nlm4_shareres *objp)
 	return TRUE;
 }
 
+bool_t
+xdr_nlm4_freeallargs (XDR *xdrs, nlm4_freeallargs *objp)
+{
+        if (!xdr_string (xdrs, &objp->name, LM_MAXSTRLEN))
+                return FALSE;
+        if (!xdr_uint32_t (xdrs, &objp->state))
+                return FALSE;
+        return TRUE;
+}
+
+
 /*
 bool_t
 xdr_nlm_sm_status (XDR *xdrs, nlm_sm_status *objp)
diff --git a/rpc/xdr/src/nlm4-xdr.h b/rpc/xdr/src/nlm4-xdr.h
index d95a6ad6e58..3799f6b1d98 100644
--- a/rpc/xdr/src/nlm4-xdr.h
+++ b/rpc/xdr/src/nlm4-xdr.h
@@ -183,6 +183,13 @@ struct nlm4_shareres {
 };
 typedef struct nlm4_shareres nlm4_shareres;
 
+struct nlm4_freeallargs {
+        char *name;
+        u_int32_t state;
+};
+typedef struct nlm4_freeallargs nlm4_freeallargs;
+
+
 #define NLM4_NULL          0
 #define NLM4_TEST          1
 #define NLM4_LOCK          2
@@ -229,6 +236,7 @@ extern  bool_t xdr_nlm4_cancargs (XDR *, nlm4_cancargs*);
 extern  bool_t xdr_nlm4_unlockargs (XDR *, nlm4_unlockargs*);
 extern  bool_t xdr_nlm4_shareargs (XDR *, nlm4_shareargs*);
 extern  bool_t xdr_nlm4_shareres (XDR *, nlm4_shareres*);
+extern  bool_t xdr_nlm4_freeallargs (XDR *, nlm4_freeallargs*);
 
 #else /* K&R C */
 extern bool_t xdr_netobj ();
@@ -248,6 +256,7 @@ extern bool_t xdr_nlm4_cancargs ();
 extern bool_t xdr_nlm4_unlockargs ();
 extern bool_t xdr_nlm4_shareargs ();
 extern bool_t xdr_nlm4_shareres ();
+extern bool_t xdr_nlm4_freeallargs ();
 
 #endif /* K&R C */
 
diff --git a/rpc/xdr/src/nlm4.x b/rpc/xdr/src/nlm4.x
index d738b27770d..a6de6f32bf4 100644
--- a/rpc/xdr/src/nlm4.x
+++ b/rpc/xdr/src/nlm4.x
@@ -74,7 +74,7 @@ struct nlm4_holder {
 };
 
 struct nlm4_lock {
-	string caller_name<MAXNAMELEN>;
+	string caller_name<LM_MAXSTRLEN>;
 	netobj fh;
 	netobj oh;
 	u_int32_t svid;
@@ -83,7 +83,7 @@ struct nlm4_lock {
 };
 
 struct nlm4_share {
-	string caller_name<MAXNAMELEN>;
+	string caller_name<LM_MAXSTRLEN>;
 	netobj fh;
 	netobj oh;
 	fsh_mode mode;
@@ -146,6 +146,11 @@ struct	nlm4_shareres {
 	int	sequence;
 };
 
+struct  nlm4_freeallargs {
+        string       name<LM_MAXSTRLEN>;   /* client hostname */
+        uint32       state;                /* unused */
+};
+
 /*
  * argument for the procedure called by rpc.statd when a monitored host
  * status change.
diff --git a/xlators/nfs/server/src/nfs-mem-types.h b/xlators/nfs/server/src/nfs-mem-types.h
index e2dae4a3403..1a3b25281ba 100644
--- a/xlators/nfs/server/src/nfs-mem-types.h
+++ b/xlators/nfs/server/src/nfs-mem-types.h
@@ -47,6 +47,7 @@ enum gf_nfs_mem_types_ {
 	gf_nfs_mt_nlm4_cm,
 	gf_nfs_mt_nlm4_fde,
         gf_nfs_mt_nlm4_nlmclnt,
+        gf_nfs_mt_nlm4_share,
         gf_nfs_mt_end
 };
 #endif
diff --git a/xlators/nfs/server/src/nfs.c b/xlators/nfs/server/src/nfs.c
index 42edc95f6d1..a48e114999a 100644
--- a/xlators/nfs/server/src/nfs.c
+++ b/xlators/nfs/server/src/nfs.c
@@ -849,6 +849,15 @@ fini (xlator_t *this)
 int32_t
 nfs_forget (xlator_t *this, inode_t *inode)
 {
+        uint64_t           ctx        = 0;
+        struct list_head  *head       = NULL;
+
+        if (inode_ctx_del (inode, this, &ctx))
+                return -1;
+
+        head = (struct list_head *)ctx;
+        GF_FREE (head);
+
         return 0;
 }
 
diff --git a/xlators/nfs/server/src/nfs3.h b/xlators/nfs/server/src/nfs3.h
index e6b9edee5ca..78eb01b60b9 100644
--- a/xlators/nfs/server/src/nfs3.h
+++ b/xlators/nfs/server/src/nfs3.h
@@ -154,6 +154,7 @@ typedef union args_ {
         nlm4_unlockargs nlm4_unlockargs;
         nlm4_shareargs nlm4_shareargs;
         nlm4_shareres nlm4_shareres;
+        nlm4_freeallargs nlm4_freeallargs;
 } args;
 
 
@@ -230,6 +231,7 @@ struct nfs3_local {
         nlm4_lkowner_t          lkowner;
         char                    cookiebytes[1024];
         struct nfs3_fh          lockfh;
+        int                     monitor;
         rpc_transport_t         *trans;
         call_frame_t            *frame;
 };
diff --git a/xlators/nfs/server/src/nlm4.c b/xlators/nfs/server/src/nlm4.c
index 4f9a1c4fcef..72f71609a51 100644
--- a/xlators/nfs/server/src/nlm4.c
+++ b/xlators/nfs/server/src/nlm4.c
@@ -199,12 +199,40 @@ nlm4_prep_nlm4_unlockargs (nlm4_unlockargs *args, struct nfs3_fh *fh,
 }
 
 void
+nlm4_prep_shareargs (nlm4_shareargs *args, struct nfs3_fh *fh,
+                     nlm4_lkowner_t *oh, char *cookiebytes)
+{
+        memset (args, 0, sizeof (*args));
+        args->share.fh.n_bytes = (void *)fh;
+        args->share.oh.n_bytes = (void *)oh;
+        args->cookie.n_bytes = (void *)cookiebytes;
+}
+
+void
+nlm4_prep_freeallargs (nlm4_freeallargs *args, nlm4_lkowner_t *oh)
+{
+        memset (args, 0, sizeof (*args));
+        args->name = (void *)oh;
+}
+
+void
 nlm_copy_lkowner (gf_lkowner_t *dst, netobj *src)
 {
         dst->len = src->n_len;
         memcpy (dst->data, src->n_bytes, dst->len);
 }
 
+int
+nlm_is_oh_same_lkowner (gf_lkowner_t *a, netobj *b)
+{
+        if (!a || !b) {
+                gf_log (GF_NLM, GF_LOG_ERROR, "invalid args");
+                return -1;
+        }
+
+        return (a->len == b->n_len &&
+                !memcmp (a->data, b->n_bytes, a->len));
+}
 
 nfsstat3
 nlm4_errno_to_nlm4stat (int errnum)
@@ -251,6 +279,7 @@ nlm4_call_state_init (struct nfs3_state *s, rpcsvc_request_t *req)
         cs->req = req;
         cs->nfsx = s->nfsx;
         cs->nfs3state = s;
+        cs->monitor = 1;
 
         return cs;
 }
@@ -270,9 +299,11 @@ nlm_monitor (char *caller_name)
                 }
         }
         UNLOCK (&nlm_client_list_lk);
-        if (monitor == -1) {
-                gf_log (GF_NLM, GF_LOG_ERROR, "%s was not found in the nlmclnt list", caller_name);
-        }
+
+        if (monitor == -1)
+                gf_log (GF_NLM, GF_LOG_ERROR, "%s was not found in "
+                        "the nlmclnt list", caller_name);
+
         return monitor;
 }
 
@@ -401,6 +432,7 @@ nlm_add_nlmclnt (char *caller_name)
 
                 INIT_LIST_HEAD(&nlmclnt->fdes);
                 INIT_LIST_HEAD(&nlmclnt->nlm_clients);
+                INIT_LIST_HEAD(&nlmclnt->shares);
 
                 list_add (&nlmclnt->nlm_clients, &nlm_client_list);
                 nlmclnt->caller_name = gf_strdup (caller_name);
@@ -541,23 +573,31 @@ out:
 }
 
 nlm_client_t *
-nlm_get_uniq (char *caller_name)
+__nlm_get_uniq (char *caller_name)
 {
         nlm_client_t *nlmclnt = NULL;
-        int nlmclnt_found = 0;
 
-        LOCK (&nlm_client_list_lk);
+        if (!caller_name)
+                return NULL;
+
         list_for_each_entry (nlmclnt, &nlm_client_list, nlm_clients) {
-                if (!strcmp(caller_name, nlmclnt->caller_name)) {
-                        nlmclnt_found = 1;
-                        break;
-                }
+                if (!strcmp(caller_name, nlmclnt->caller_name))
+                        return nlmclnt;
         }
+
+        return NULL;
+}
+
+nlm_client_t *
+nlm_get_uniq (char *caller_name)
+{
+        nlm_client_t *nlmclnt = NULL;
+
+        LOCK (&nlm_client_list_lk);
+        nlmclnt = __nlm_get_uniq (caller_name);
         UNLOCK (&nlm_client_list_lk);
-        if (nlmclnt_found)
-                return nlmclnt;
-        else
-                return NULL;
+
+        return nlmclnt;
 }
 
 
@@ -1247,11 +1287,11 @@ nlm4svc_lock_cbk (call_frame_t *frame, void *cookie, xlator_t *this,
                   int32_t op_ret, int32_t op_errno, struct gf_flock *flock,
                   dict_t *xdata)
 {
-        nlm4_stats                      stat = nlm4_denied;
-        nfs3_call_state_t              *cs = NULL;
-        int                             transit_cnt = -1;
+        nlm4_stats                       stat        = nlm4_denied;
+        int                              transit_cnt = -1;
         char                            *caller_name = NULL;
-        pthread_t thr;
+        nfs3_call_state_t               *cs          = NULL;
+        pthread_t                        thr;
 
         cs = frame->local;
         caller_name = cs->args.nlm4_lockargs.alock.caller_name;
@@ -1265,7 +1305,7 @@ nlm4svc_lock_cbk (call_frame_t *frame, void *cookie, xlator_t *this,
                 goto err;
         } else {
                 stat = nlm4_granted;
-                if (!nlm_monitor (caller_name)) {
+                if (cs->monitor && !nlm_monitor (caller_name)) {
                         /* FIXME: handle nsm_monitor failure */
                         pthread_create (&thr, NULL, nsm_monitor, (void*)caller_name);
                 }
@@ -1331,8 +1371,8 @@ int
 nlm4_lock_resume (void *carg)
 {
         nlm4_stats                      stat = nlm4_failed;
-        int                             ret = -1;
-        nfs3_call_state_t               *cs = NULL;
+        int                             ret  = -1;
+        nfs3_call_state_t              *cs   = NULL;
 
         if (!carg)
                 return ret;
@@ -1354,17 +1394,16 @@ nlm4err:
         return ret;
 }
 
-
 int
-nlm4svc_lock (rpcsvc_request_t *req)
+nlm4svc_lock_common (rpcsvc_request_t *req, int mon)
 {
-        xlator_t                        *vol = NULL;
-        nlm4_stats                      stat = nlm4_failed;
-        struct nfs_state               *nfs = NULL;
-        nfs3_state_t                   *nfs3 = NULL;
-        nfs3_call_state_t               *cs = NULL;
-        int                             ret = RPCSVC_ACTOR_ERROR;
-        struct nfs3_fh                  fh = {{0}, };
+        int                              ret      = RPCSVC_ACTOR_ERROR;
+        nlm4_stats                       stat     = nlm4_failed;
+        struct nfs3_fh                   fh       = {{0}, };
+        xlator_t                        *vol      = NULL;
+        nfs3_state_t                    *nfs3     = NULL;
+        nfs3_call_state_t               *cs       = NULL;
+        struct nfs_state                *nfs      = NULL;
 
         if (!req)
                 return ret;
@@ -1381,7 +1420,9 @@ nlm4svc_lock (rpcsvc_request_t *req)
                 rpcsvc_request_seterr (req, GARBAGE_ARGS);
                 goto rpcerr;
         }
+
         fh = cs->lockfh;
+        cs->monitor = mon;
         nlm4_validate_gluster_fh (&fh, stat, nlm4err);
         nlm4_map_fh_to_volume (cs->nfs3state, fh, req, vol, stat, nlm4err);
 
@@ -1415,10 +1456,23 @@ rpcerr:
         if (ret < 0) {
                 nfs3_call_state_wipe (cs);
         }
+
         return ret;
 }
 
 int
+nlm4svc_lock (rpcsvc_request_t *req)
+{
+        return nlm4svc_lock_common (req, 1);
+}
+
+int
+nlm4svc_nm_lock (rpcsvc_request_t *req)
+{
+        return nlm4svc_lock_common (req, 0);
+}
+
+int
 nlm4svc_cancel_cbk (call_frame_t *frame, void *cookie, xlator_t *this,
                     int32_t op_ret, int32_t op_errno, struct gf_flock *flock,
                     dict_t *xdata)
@@ -1729,6 +1783,500 @@ rpcerr:
         return ret;
 }
 
+int
+nlm4_share_reply (nfs3_call_state_t *cs, nlm4_stats stat)
+{
+        nlm4_shareres  res = {{0}, 0, 0};
+
+        if (!cs)
+                return -1;
+
+        res.cookie = cs->args.nlm4_shareargs.cookie;
+        res.stat = stat;
+        res.sequence = 0;
+
+        nlm4svc_submit_reply (cs->req, (void *)&res,
+                              (nlm4_serializer)xdr_serialize_nlm4_shareres);
+        return 0;
+}
+
+nlm_share_t *
+nlm4_share_new ()
+{
+        nlm_share_t      *share     = NULL;
+
+        share = GF_CALLOC (1, sizeof (nlm_share_t),
+                           gf_nfs_mt_nlm4_share);
+        if (!share)
+                goto out;
+
+        INIT_LIST_HEAD (&share->client_list);
+        INIT_LIST_HEAD (&share->inode_list);
+ out:
+        return share;
+}
+
+int
+nlm4_add_share_to_inode (nlm_share_t *share)
+{
+        int                    ret     = -1;
+        uint64_t               ctx     = 0;
+        struct list_head      *head    = NULL;
+        xlator_t              *this    = NULL;
+        inode_t               *inode   = NULL;
+
+        this = THIS;
+        inode = share->inode;
+        ret = inode_ctx_get (inode, this, &ctx);
+
+        head = (struct list_head *)ctx;
+
+        if (ret || !head) {
+                head = GF_CALLOC (1, sizeof (struct list_head),
+                                  gf_common_mt_list_head);
+                if (!head ) {
+                        ret = -1;
+                        goto out;
+                }
+
+                INIT_LIST_HEAD (head);
+                ret = inode_ctx_put (inode, this, (uint64_t)head);
+                if (ret)
+                        goto out;
+        }
+
+        list_add (&share->inode_list, head);
+
+ out:
+        if (ret && head)
+                GF_FREE (head);
+
+        return ret;
+}
+
+int
+nlm4_approve_share_reservation (nfs3_call_state_t *cs)
+{
+        int                       ret               = -1;
+        uint64_t                  ctx               = 0;
+        fsh_mode                  req_mode          = 0;
+        fsh_access                req_access        = 0;
+        inode_t                  *inode             = NULL;
+        nlm_share_t              *share             = NULL;
+        struct list_head         *head              = NULL;
+
+        if (!cs)
+                goto out;
+
+        inode = cs->resolvedloc.inode;
+
+        ret = inode_ctx_get (inode, THIS, &ctx);
+        if (ret) {
+                ret = 0;
+                goto out;
+        }
+
+        head = (struct list_head *)ctx;
+        if (!head || list_empty (head))
+                goto out;
+
+        req_mode = cs->args.nlm4_shareargs.share.mode;
+        req_access = cs->args.nlm4_shareargs.share.access;
+
+        list_for_each_entry (share, head, inode_list) {
+                ret = (((req_mode & share->access) == 0) &&
+                       ((req_access & share->mode) == 0));
+                if (!ret) {
+                        ret = -1;
+                        goto out;
+                }
+        }
+        ret = 0;
+
+ out:
+         return ret;
+}
+
+int
+nlm4_create_share_reservation (nfs3_call_state_t *cs)
+{
+        int                       ret        = -1;
+        nlm_share_t              *share      = NULL;
+        nlm_client_t             *client     = NULL;
+        inode_t                  *inode      = NULL;
+
+        LOCK (&nlm_client_list_lk);
+
+        inode = inode_ref (cs->resolvedloc.inode);
+        if (!inode) {
+                gf_log (GF_NLM, GF_LOG_ERROR, "inode not found");
+                goto out;
+        }
+
+        client = __nlm_get_uniq (cs->args.nlm4_shareargs.share.caller_name);
+        if (!client) {
+                /* DO NOT add client. the client is supposed
+                   to be here, since nlm4svc_share adds it */
+                gf_log (GF_NLM, GF_LOG_ERROR, "client not found");
+                goto out;
+        }
+
+        ret = nlm4_approve_share_reservation (cs);
+        if (ret)
+                goto out;
+
+        share = nlm4_share_new ();
+        if (!share) {
+                ret = -1;
+                goto out;
+        }
+
+        share->inode  = inode;
+        share->mode   = cs->args.nlm4_shareargs.share.mode;
+        share->access = cs->args.nlm4_shareargs.share.access;
+        nlm_copy_lkowner (&share->lkowner,
+                          &cs->args.nlm4_shareargs.share.oh);
+
+        ret = nlm4_add_share_to_inode (share);
+        if (ret)
+                goto out;
+
+        list_add (&share->client_list, &client->shares);
+
+ out:
+        if (ret && inode) {
+                inode_unref (inode);
+                if (share)
+                        GF_FREE (share);
+        }
+
+        UNLOCK (&nlm_client_list_lk);
+        return ret;
+}
+
+/*
+  SHARE and UNSHARE calls DO NOT perform STACK_WIND,
+  the (non-monitored) share reservations are maintained
+  at *nfs xlator level only*, in memory
+*/
+int
+nlm4_share_resume (void *call_state)
+{
+        int                             ret             = -1;
+        nlm4_stats                      stat            = nlm4_failed;
+        nfs3_call_state_t              *cs              = NULL;
+
+        if (!call_state)
+                return ret;
+
+        cs = (nfs3_call_state_t *)call_state;
+        nlm4_check_fh_resolve_status (cs, stat, out);
+
+        ret = nlm4_create_share_reservation (cs);
+        if (!ret)
+                stat = nlm4_granted;
+
+ out:
+        nlm4_share_reply (cs, stat);
+        nfs3_call_state_wipe (cs);
+        return 0;
+}
+
+int
+nlm4svc_share (rpcsvc_request_t *req)
+{
+        nlm4_stats                    stat      = nlm4_failed;
+        xlator_t                     *vol       = NULL;
+        nfs3_state_t                 *nfs3      = NULL;
+        nfs3_call_state_t            *cs        = NULL;
+        struct nfs_state             *nfs       = NULL;
+        struct nfs3_fh                fh        = {{0}, };
+        int                           ret       = RPCSVC_ACTOR_ERROR;
+
+        if (!req)
+                return ret;
+
+        nlm4_validate_nfs3_state (req, nfs3, stat, rpcerr, ret);
+        nfs = nfs_state (nfs3->nfsx);
+        nlm4_handle_call_state_init (nfs->nfs3state, cs, req,
+                                     stat, rpcerr);
+
+        nlm4_prep_shareargs (&cs->args.nlm4_shareargs, &cs->lockfh,
+                             &cs->lkowner, cs->cookiebytes);
+
+        if (xdr_to_nlm4_shareargs (req->msg[0],
+                                   &cs->args.nlm4_shareargs) <= 0) {
+                gf_log (GF_NLM, GF_LOG_ERROR, "Error decoding SHARE args");
+                rpcsvc_request_seterr (req, GARBAGE_ARGS);
+                goto rpcerr;
+        }
+
+        fh = cs->lockfh;
+        nlm4_validate_gluster_fh (&fh, stat, nlm4err);
+        nlm4_map_fh_to_volume (cs->nfs3state, fh, req,
+                               vol, stat, nlm4err);
+
+        if (nlm_grace_period && !cs->args.nlm4_shareargs.reclaim) {
+                gf_log (GF_NLM, GF_LOG_DEBUG, "NLM in grace period");
+                stat = nlm4_denied_grace_period;
+                nlm4_share_reply (cs, stat);
+                nfs3_call_state_wipe (cs);
+                return 0;
+        }
+
+        cs->vol = vol;
+        cs->trans = rpcsvc_request_transport_ref(req);
+        nlm4_volume_started_check (nfs3, vol, ret, rpcerr);
+
+        ret = nlm_add_nlmclnt (cs->args.nlm4_shareargs.share.caller_name);
+
+        ret = nfs3_fh_resolve_and_resume (cs, &fh, NULL, nlm4_share_resume);
+
+ nlm4err:
+        if (ret < 0) {
+                gf_log (GF_NLM, GF_LOG_ERROR, "SHARE call failed");
+                nlm4_share_reply (cs, stat);
+                nfs3_call_state_wipe (cs);
+                return 0;
+        }
+
+ rpcerr:
+        if (ret < 0)
+                nfs3_call_state_wipe (cs);
+
+        return ret;
+}
+
+int
+nlm4_remove_share_reservation (nfs3_call_state_t *cs)
+{
+        int                ret        = -1;
+        uint64_t           ctx        = 0;
+        fsh_mode           req_mode   = 0;
+        fsh_access         req_access = 0;
+        nlm_share_t       *share      = NULL;
+        nlm_share_t       *tmp        = NULL;
+        nlm_client_t      *client     = NULL;
+        char              *caller     = NULL;
+        inode_t           *inode      = NULL;
+        xlator_t          *this       = NULL;
+        struct list_head  *head       = NULL;
+        nlm4_shareargs    *args       = NULL;
+
+        LOCK (&nlm_client_list_lk);
+
+        args = &cs->args.nlm4_shareargs;
+        caller = args->share.caller_name;
+
+        client = __nlm_get_uniq (caller);
+        if (!client) {
+                gf_log (GF_NLM, GF_LOG_ERROR,
+                        "client not found: %s", caller);
+                goto out;
+        }
+
+        inode = cs->resolvedloc.inode;
+        if (!inode) {
+                gf_log (GF_NLM, GF_LOG_ERROR,
+                        "inode not found: client: %s", caller);
+                goto out;
+        }
+
+        this = THIS;
+        ret = inode_ctx_get (inode, this, &ctx);
+        if (ret) {
+                gf_log (GF_NLM, GF_LOG_ERROR,
+                        "no shares found for inode:"
+                        "gfid: %s; client: %s",
+                        inode->gfid, caller);
+                goto out;
+        }
+
+        head = (struct list_head *)ctx;
+        if (list_empty (head)) {
+                ret = -1;
+                goto out;
+        }
+
+        ret = 0;
+        req_mode = args->share.mode;
+        req_access = args->share.access;
+
+        list_for_each_entry_safe (share, tmp, head, inode_list) {
+                ret = ((req_mode == share->mode) &&
+                       (req_access == share->access) &&
+                       nlm_is_oh_same_lkowner (&share->lkowner, &args->share.oh));
+                if (ret) {
+                        list_del (&share->client_list);
+                        list_del (&share->inode_list);
+                        inode_unref (share->inode);
+                        GF_FREE (share);
+                        break;
+                }
+        }
+
+        ret = 0;
+ out:
+        UNLOCK (&nlm_client_list_lk);
+        return ret;
+
+}
+
+int
+nlm4_unshare_resume (void *call_state)
+{
+        int                ret        = -1;
+        nlm4_stats         stat       = nlm4_failed;
+        nfs3_call_state_t *cs         = NULL;
+
+        if (!call_state)
+                return ret;
+
+        cs = (nfs3_call_state_t *)call_state;
+
+        nlm4_check_fh_resolve_status (cs, stat, out);
+        ret = nlm4_remove_share_reservation (cs);
+        if (!ret)
+                stat = nlm4_granted;
+
+ out:
+        nlm4_share_reply (cs, stat);
+        nfs3_call_state_wipe (cs);
+        return 0;
+}
+
+int
+nlm4svc_unshare (rpcsvc_request_t *req)
+{
+        nlm4_stats                    stat      = nlm4_failed;
+        xlator_t                     *vol       = NULL;
+        nfs3_state_t                 *nfs3      = NULL;
+        nfs3_call_state_t            *cs        = NULL;
+        struct nfs_state             *nfs       = NULL;
+        struct nfs3_fh                fh        = {{0}, };
+        int                           ret       = RPCSVC_ACTOR_ERROR;
+
+        if (!req)
+                return ret;
+
+        nlm4_validate_nfs3_state (req, nfs3, stat, rpcerr, ret);
+        nfs = nfs_state (nfs3->nfsx);
+        nlm4_handle_call_state_init (nfs->nfs3state, cs, req,
+                                     stat, rpcerr);
+
+        nlm4_prep_shareargs (&cs->args.nlm4_shareargs, &cs->lockfh,
+                             &cs->lkowner, cs->cookiebytes);
+
+        if (xdr_to_nlm4_shareargs (req->msg[0],
+                                   &cs->args.nlm4_shareargs) <= 0) {
+                gf_log (GF_NLM, GF_LOG_ERROR, "Error decoding UNSHARE args");
+                rpcsvc_request_seterr (req, GARBAGE_ARGS);
+                goto rpcerr;
+        }
+
+        fh = cs->lockfh;
+        nlm4_validate_gluster_fh (&fh, stat, nlm4err);
+        nlm4_map_fh_to_volume (cs->nfs3state, fh, req,
+                               vol, stat, nlm4err);
+
+        if (nlm_grace_period && !cs->args.nlm4_shareargs.reclaim) {
+                gf_log (GF_NLM, GF_LOG_DEBUG, "NLM in grace period");
+                stat = nlm4_denied_grace_period;
+                nlm4_share_reply (cs, stat);
+                nfs3_call_state_wipe (cs);
+                return 0;
+        }
+
+        cs->vol = vol;
+        cs->trans = rpcsvc_request_transport_ref(req);
+        nlm4_volume_started_check (nfs3, vol, ret, rpcerr);
+
+        ret = nfs3_fh_resolve_and_resume (cs, &fh, NULL,
+                                          nlm4_unshare_resume);
+
+ nlm4err:
+        if (ret < 0) {
+                gf_log (GF_NLM, GF_LOG_ERROR, "UNSHARE call failed");
+                nlm4_share_reply (cs, stat);
+                ret = 0;
+                return 0;
+        }
+
+ rpcerr:
+        if (ret < 0)
+                nfs3_call_state_wipe (cs);
+
+        return ret;
+}
+
+int
+nlm4_free_all_shares (char *caller_name)
+{
+        nlm_share_t             *share      = NULL;
+        nlm_share_t             *tmp        = NULL;
+        nlm_client_t            *client     = NULL;
+
+        LOCK (&nlm_client_list_lk);
+
+        client = __nlm_get_uniq (caller_name);
+        if (!client) {
+                gf_log (GF_NLM, GF_LOG_DEBUG,
+                        "client not found: %s", caller_name);
+                goto out;
+        }
+
+        list_for_each_entry_safe (share, tmp, &client->shares, client_list) {
+                list_del (&share->inode_list);
+                list_del (&share->client_list);
+                inode_unref (share->inode);
+                GF_FREE (share);
+        }
+ out:
+        UNLOCK (&nlm_client_list_lk);
+        return 0;
+}
+
+int
+nlm4svc_free_all (rpcsvc_request_t *req)
+{
+        int                           ret       = RPCSVC_ACTOR_ERROR;
+        nlm4_stats                    stat      = nlm4_failed;
+        nfs3_state_t                 *nfs3      = NULL;
+        nfs3_call_state_t            *cs        = NULL;
+        struct nfs_state             *nfs       = NULL;
+
+        nlm4_validate_nfs3_state (req, nfs3, stat, err, ret);
+        nfs = nfs_state (nfs3->nfsx);
+        nlm4_handle_call_state_init (nfs->nfs3state, cs,
+                                     req, stat, err);
+
+        nlm4_prep_freeallargs (&cs->args.nlm4_freeallargs,
+                               &cs->lkowner);
+
+        if (xdr_to_nlm4_freeallargs (req->msg[0],
+                                     &cs->args.nlm4_freeallargs) <= 0) {
+                gf_log (GF_NLM, GF_LOG_ERROR, "Error decoding FREE_ALL args");
+                rpcsvc_request_seterr (req, GARBAGE_ARGS);
+                goto err;
+        }
+
+        ret = nlm4_free_all_shares (cs->args.nlm4_freeallargs.name);
+        if (ret)
+                goto err;
+
+        ret = nlm_cleanup_fds (cs->args.nlm4_freeallargs.name);
+        if (ret)
+                goto err;
+
+ err:
+        nfs3_call_state_wipe (cs);
+        if (ret)
+                gf_log (GF_NLM, GF_LOG_DEBUG,
+                        "error in free all; stat: %d", stat);
+        return ret;
+
+}
+
 void
 nlm4svc_sm_notify (struct nlm_sm_status *status)
 {
@@ -1757,17 +2305,17 @@ rpcsvc_actor_t  nlm4svc_actors[NLM4_PROC_COUNT] = {
         {"LOCK",       NLM4_LOCK_RES,     NULL,              NULL, NULL},
         {"CANCEL",     NLM4_CANCEL_RES,   NULL,              NULL, NULL},
         {"UNLOCK",     NLM4_UNLOCK_RES,   NULL,              NULL, NULL},
-        /* 15 ; 17,18,19 are dummy actors */
+        /* 15 ; procedures 17,18,19 are not defined by nlm */
         {"GRANTED",    NLM4_GRANTED_RES,  NULL,              NULL, NULL},
         {"SM_NOTIFY",  NLM4_SM_NOTIFY,    NULL,              NULL, NULL},
         {"SEVENTEEN",  NLM4_SEVENTEEN,    NULL,              NULL, NULL},
         {"EIGHTEEN",   NLM4_EIGHTEEN,     NULL,              NULL, NULL},
         {"NINETEEN",   NLM4_NINETEEN,     NULL,              NULL, NULL},
         /* 20 */
-        {"SHARE",      NLM4_SHARE,        NULL,              NULL, NULL},
-        {"UNSHARE",    NLM4_UNSHARE,      NULL,              NULL, NULL},
-        {"NM_LOCK",    NLM4_NM_LOCK,      NULL,              NULL, NULL},
-        {"FREE_ALL",   NLM4_FREE_ALL,     nlm4svc_null,      NULL, NULL},
+        {"SHARE",      NLM4_SHARE,        nlm4svc_share,     NULL, NULL},
+        {"UNSHARE",    NLM4_UNSHARE,      nlm4svc_unshare,   NULL, NULL},
+        {"NM_LOCK",    NLM4_NM_LOCK,      nlm4svc_nm_lock,   NULL, NULL},
+        {"FREE_ALL",   NLM4_FREE_ALL,     nlm4svc_free_all,  NULL, NULL},
 };
 
 rpcsvc_program_t        nlm4prog = {
diff --git a/xlators/nfs/server/src/nlm4.h b/xlators/nfs/server/src/nlm4.h
index db5874387f4..bcc7ae57343 100644
--- a/xlators/nfs/server/src/nlm4.h
+++ b/xlators/nfs/server/src/nlm4.h
@@ -60,11 +60,21 @@ typedef struct nlm_client {
         pid_t uniq;
         struct list_head nlm_clients;
         struct list_head fdes;
+        struct list_head shares;
         struct rpc_clnt *rpc_clnt;
         char *caller_name;
         int nsm_monitor;
 } nlm_client_t;
 
+typedef struct nlm_share {
+        struct list_head     client_list;
+        struct list_head     inode_list;
+        gf_lkowner_t         lkowner;
+        inode_t             *inode;
+        fsh_mode             mode;
+        fsh_access           access;
+} nlm_share_t;
+
 typedef struct nlm_fde {
         struct list_head fde_list;
         fd_t *fd;