Commit 76db6d95 authored by Andy Adamson's avatar Andy Adamson Committed by Benny Halevy
Browse files

nfs41: add session setup to the state manager 



At mount, nfs_alloc_client sets the cl_state NFS4CLNT_LEASE_EXPIRED bit
and nfs4_alloc_session sets the NFS4CLNT_SESSION_SETUP bit, so both bits are
set when nfs4_lookup_root calls nfs4_recover_expired_lease which schedules
the nfs4_state_manager and waits for it to complete.

Place the session setup after the clientid establishment in nfs4_state_manager
so that the session is setup right after the clientid has been established
without rescheduling the state manager.

Unlike nfsv4.0, the nfs_client struct is not ready to use until the session
has been established.  Postpone marking the nfs_client struct to NFS_CS_READY
until after a successful CREATE_SESSION call so that other threads cannot use
the client until the session is established.

If the EXCHANGE_ID call fails and the session has not been setup (the
NFS4CLNT_SESSION_SETUP bit is set), mark the client with the error and return.

If the session setup CREATE_SESSION call fails with NFS4ERR_STALE_CLIENTID
which could occur due to server reboot or network partition inbetween the
EXCHANGE_ID and CREATE_SESSION call, reset the NFS4CLNT_LEASE_EXPIRED and
NFS4CLNT_SESSION_SETUP bits and try again.

If the CREATE_SESSION call fails with other errors, mark the client with
the error and return.

Signed-off-by: default avatarAndy Adamson <andros@netapp.com>
Signed-off-by: default avatarBenny Halevy <bhalevy@panasas.com>

[nfs41: NFS_CS_SESSION_SETUP cl_cons_state for back channel setup]
  On session setup, the CREATE_SESSION reply races with the server back channel
  probe which needs to succeed to setup the back channel. Set a new
  cl_cons_state NFS_CS_SESSION_SETUP just prior to the CREATE_SESSION call
  and add it as a valid state to nfs_find_client so that the client back channel
  can find the nfs_client struct and won't drop the server backchannel probe.
  Use a new cl_cons_state so that NFSv4.0 back channel behaviour which only
  sets NFS_CS_READY is unchanged.
  Adjust waiting on the nfs_client_active_wq accordingly.
Signed-off-by: default avatarAndy Adamson <andros@netapp.com>
Signed-off-by: default avatarBenny Halevy <bhalevy@panasas.com>

[nfs41: rename NFS_CS_SESSION_SETUP to NFS_CS_SESSION_INITING]
Signed-off-by: default avatarAndy Adamson <andros@netapp.com>
[nfs41: set NFS_CL_SESSION_INITING in alloc_session]
Signed-off-by: default avatarAndy Adamson <andros@netapp.com>
[nfs41: move session setup into a function]
Signed-off-by: default avatarAndy Adamson <andros@netapp.com>
Signed-off-by: default avatarBenny Halevy <bhalevy@panasas.com>
[moved nfs4_proc_create_session declaration here]
Signed-off-by: default avatarBenny Halevy <bhalevy@panasas.com>
Signed-off-by: default avatarTrond Myklebust <Trond.Myklebust@netapp.com>
parent ac72b7b3

fs/nfs/client.c

+6 −4
Original line number Diff line number Diff line
@@ -366,7 +366,8 @@ struct nfs_client *nfs_find_client(const struct sockaddr *addr, u32 nfsversion) 
		struct sockaddr *clap = (struct sockaddr *)&clp->cl_addr;



		/* Don't match clients that failed to initialise properly */

		if (clp->cl_cons_state != NFS_CS_READY)

		if (!(clp->cl_cons_state == NFS_CS_READY ||

		      clp->cl_cons_state == NFS_CS_SESSION_INITING))

			continue;



		/* Different NFS versions cannot share the same nfs_client */
@@ -499,7 +500,7 @@ found_client: 
		nfs_free_client(new);



	error = wait_event_killable(nfs_client_active_wq,

				clp->cl_cons_state != NFS_CS_INITING);

				clp->cl_cons_state < NFS_CS_INITING);

	if (error < 0) {

		nfs_put_client(clp);

		return ERR_PTR(-ERESTARTSYS);
@@ -520,7 +521,7 @@ found_client: 
/*

 * Mark a server as ready or failed

 */

static void nfs_mark_client_ready(struct nfs_client *clp, int state)

void nfs_mark_client_ready(struct nfs_client *clp, int state)

{

	clp->cl_cons_state = state;

	wake_up_all(&nfs_client_active_wq);
@@ -1135,6 +1136,7 @@ static int nfs4_init_client(struct nfs_client *clp, 
	if (error < 0)

		goto error;



	if (!nfs4_has_session(clp))

		nfs_mark_client_ready(clp, NFS_CS_READY);

	return 0;

fs/nfs/internal.h

+1 −0
Original line number Diff line number Diff line
@@ -100,6 +100,7 @@ extern void nfs_free_server(struct nfs_server *server); 
extern struct nfs_server *nfs_clone_server(struct nfs_server *,

					   struct nfs_fh *,

					   struct nfs_fattr *);

extern void nfs_mark_client_ready(struct nfs_client *clp, int state);

#ifdef CONFIG_PROC_FS

extern int __init nfs_fs_proc_init(void);

extern void nfs_fs_proc_exit(void);

fs/nfs/nfs4_fs.h

+2 −0
Original line number Diff line number Diff line
@@ -44,6 +44,7 @@ enum nfs4_client_state { 
	NFS4CLNT_RECLAIM_REBOOT,

	NFS4CLNT_RECLAIM_NOGRACE,

	NFS4CLNT_DELEGRETURN,

	NFS4CLNT_SESSION_SETUP,

};



/*
@@ -208,6 +209,7 @@ extern int nfs4_setup_sequence(struct nfs_client *clp, 
		int cache_reply, struct rpc_task *task);

extern void nfs4_destroy_session(struct nfs4_session *session);

extern struct nfs4_session *nfs4_alloc_session(struct nfs_client *clp);

extern int nfs4_proc_create_session(struct nfs_client *, int reset);

#else /* CONFIG_NFS_v4_1 */

static inline int nfs4_setup_sequence(struct nfs_client *clp,

		struct nfs4_sequence_args *args, struct nfs4_sequence_res *res,

fs/nfs/nfs4proc.c

+10 −0
Original line number Diff line number Diff line
@@ -4382,6 +4382,16 @@ struct nfs4_session *nfs4_alloc_session(struct nfs_client *clp) 
	session = kzalloc(sizeof(struct nfs4_session), GFP_KERNEL);

	if (!session)

		return NULL;



	set_bit(NFS4CLNT_SESSION_SETUP, &clp->cl_state);

	/*

	 * The create session reply races with the server back

	 * channel probe. Mark the client NFS_CS_SESSION_INITING

	 * so that the client back channel can find the

	 * nfs_client struct

	 */

	clp->cl_cons_state = NFS_CS_SESSION_INITING;



	tbl = &session->fc_slot_table;

	spin_lock_init(&tbl->slot_tbl_lock);

	rpc_init_wait_queue(&tbl->slot_tbl_waitq, "Slot table");

fs/nfs/nfs4state.c

+34 −1
Original line number Diff line number Diff line
@@ -1113,6 +1113,27 @@ static int nfs4_reclaim_lease(struct nfs_client *clp) 
	return status;

}



#ifdef CONFIG_NFS_V4_1



static int nfs4_initialize_session(struct nfs_client *clp)

{

	int status;



	status = nfs4_proc_create_session(clp, 0);

	if (!status) {

		nfs_mark_client_ready(clp, NFS_CS_READY);

	} else if (status == -NFS4ERR_STALE_CLIENTID) {

		set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);

		set_bit(NFS4CLNT_SESSION_SETUP, &clp->cl_state);

	} else {

		nfs_mark_client_ready(clp, status);

	}

	return status;

}

#else /* CONFIG_NFS_V4_1 */

static int nfs4_initialize_session(struct nfs_client *clp) { return 0; }

#endif /* CONFIG_NFS_V4_1 */



static void nfs4_state_manager(struct nfs_client *clp)

{

	int status = 0;
@@ -1126,6 +1147,9 @@ static void nfs4_state_manager(struct nfs_client *clp) 
				set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);

				if (status == -EAGAIN)

					continue;

				if (clp->cl_cons_state ==

							NFS_CS_SESSION_INITING)

					nfs_mark_client_ready(clp, status);

				goto out_error;

			}

			clear_bit(NFS4CLNT_CHECK_LEASE, &clp->cl_state);
@@ -1136,7 +1160,16 @@ static void nfs4_state_manager(struct nfs_client *clp) 
			if (status != 0)

				continue;

		}



		/* Setup the session */

		if (nfs4_has_session(clp) &&

		   test_and_clear_bit(NFS4CLNT_SESSION_SETUP, &clp->cl_state)) {

			status = nfs4_initialize_session(clp);

			if (status) {

				if (status == -NFS4ERR_STALE_CLIENTID)

					continue;

				goto out_error;

			}

		}

		/* First recover reboot state... */

		if (test_and_clear_bit(NFS4CLNT_RECLAIM_REBOOT, &clp->cl_state)) {

			status = nfs4_do_reclaim(clp, &nfs4_reboot_recovery_ops);

CRA Git | Maintained and supported by SUSTech CRA and CCSE