From 3bd2384a77e7b277c1fd8dd4ebb071162e2d85b6 Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Fri, 9 Aug 2013 12:49:19 -0400 Subject: [PATCH] NFS: NFSv4.0 transport blocking Plumb in a mechanism for plugging an NFSv4.0 mount, using the same infrastructure as NFSv4.1 sessions. Signed-off-by: Chuck Lever Signed-off-by: Trond Myklebust --- fs/nfs/nfs4proc.c | 82 +++++++++++++++++++++++++++++++++++++++++------ fs/nfs/nfs4xdr.c | 13 ++++---- 2 files changed, 79 insertions(+), 16 deletions(-) diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c index 3b5166c20962..e9e58cc34c61 100644 --- a/fs/nfs/nfs4proc.c +++ b/fs/nfs/nfs4proc.c @@ -484,6 +484,67 @@ static void nfs4_set_sequence_privileged(struct nfs4_sequence_args *args) args->sa_privileged = 1; } +static int nfs40_setup_sequence(const struct nfs_server *server, + struct nfs4_sequence_args *args, + struct nfs4_sequence_res *res, + struct rpc_task *task) +{ + struct nfs4_slot_table *tbl = server->nfs_client->cl_slot_tbl; + struct nfs4_slot *slot; + + /* slot already allocated? */ + if (res->sr_slot != NULL) + goto out_start; + + spin_lock(&tbl->slot_tbl_lock); + if (nfs4_slot_tbl_draining(tbl) && !args->sa_privileged) + goto out_sleep; + + slot = nfs4_alloc_slot(tbl); + if (IS_ERR(slot)) { + if (slot == ERR_PTR(-ENOMEM)) + task->tk_timeout = HZ >> 2; + goto out_sleep; + } + spin_unlock(&tbl->slot_tbl_lock); + + args->sa_slot = slot; + res->sr_slot = slot; + +out_start: + rpc_call_start(task); + return 0; + +out_sleep: + if (args->sa_privileged) + rpc_sleep_on_priority(&tbl->slot_tbl_waitq, task, + NULL, RPC_PRIORITY_PRIVILEGED); + else + rpc_sleep_on(&tbl->slot_tbl_waitq, task, NULL); + spin_unlock(&tbl->slot_tbl_lock); + return -EAGAIN; +} + +static int nfs40_sequence_done(struct rpc_task *task, + struct nfs4_sequence_res *res) +{ + struct nfs4_slot *slot = res->sr_slot; + struct nfs4_slot_table *tbl; + + if (!RPC_WAS_SENT(task)) + goto out; + + tbl = slot->table; + spin_lock(&tbl->slot_tbl_lock); + if (!nfs41_wake_and_assign_slot(tbl, slot)) + nfs4_free_slot(tbl, slot); + spin_unlock(&tbl->slot_tbl_lock); + + res->sr_slot = NULL; +out: + return 1; +} + #if defined(CONFIG_NFS_V4_1) static void nfs41_sequence_free_slot(struct nfs4_sequence_res *res) @@ -629,6 +690,8 @@ static int nfs4_sequence_done(struct rpc_task *task, { if (res->sr_slot == NULL) return 1; + if (!res->sr_slot->table->session) + return nfs40_sequence_done(task, res); return nfs41_sequence_done(task, res); } @@ -704,17 +767,15 @@ static int nfs4_setup_sequence(const struct nfs_server *server, struct nfs4_session *session = nfs4_get_session(server); int ret = 0; - if (session == NULL) { - rpc_call_start(task); - goto out; - } + if (!session) + return nfs40_setup_sequence(server, args, res, task); dprintk("--> %s clp %p session %p sr_slot %u\n", __func__, session->clp, session, res->sr_slot ? res->sr_slot->slot_nr : NFS4_NO_SLOT); ret = nfs41_setup_sequence(session, args, res, task); -out: + dprintk("<-- %s status=%d\n", __func__, ret); return ret; } @@ -741,22 +802,23 @@ static const struct rpc_call_ops nfs41_call_sync_ops = { .rpc_call_done = nfs41_call_sync_done, }; -#else +#else /* !CONFIG_NFS_V4_1 */ + static int nfs4_setup_sequence(const struct nfs_server *server, struct nfs4_sequence_args *args, struct nfs4_sequence_res *res, struct rpc_task *task) { - rpc_call_start(task); - return 0; + return nfs40_setup_sequence(server, args, res, task); } static int nfs4_sequence_done(struct rpc_task *task, struct nfs4_sequence_res *res) { - return 1; + return nfs40_sequence_done(task, res); } -#endif /* CONFIG_NFS_V4_1 */ + +#endif /* !CONFIG_NFS_V4_1 */ static void nfs40_call_sync_prepare(struct rpc_task *task, void *calldata) { diff --git a/fs/nfs/nfs4xdr.c b/fs/nfs/nfs4xdr.c index 4593728b9d0b..cb5f94640be6 100644 --- a/fs/nfs/nfs4xdr.c +++ b/fs/nfs/nfs4xdr.c @@ -1858,11 +1858,10 @@ static void encode_sequence(struct xdr_stream *xdr, struct nfs4_slot *slot = args->sa_slot; __be32 *p; - if (slot == NULL) - return; - tp = slot->table; session = tp->session; + if (!session) + return; encode_op_hdr(xdr, OP_SEQUENCE, decode_sequence_maxsz, hdr); @@ -2043,9 +2042,9 @@ static void encode_free_stateid(struct xdr_stream *xdr, static u32 nfs4_xdr_minorversion(const struct nfs4_sequence_args *args) { #if defined(CONFIG_NFS_V4_1) - - if (args->sa_slot) - return args->sa_slot->table->session->clp->cl_mvops->minor_version; + struct nfs4_session *session = args->sa_slot->table->session; + if (session) + return session->clp->cl_mvops->minor_version; #endif /* CONFIG_NFS_V4_1 */ return 0; } @@ -5595,6 +5594,8 @@ static int decode_sequence(struct xdr_stream *xdr, if (res->sr_slot == NULL) return 0; + if (!res->sr_slot->table->session) + return 0; status = decode_op_hdr(xdr, OP_SEQUENCE); if (!status) -- 2.39.5