NFS: Ensure that the asynchronous RPC calls complete on nfsiod.

We want to ensure that rpc_call_ops that involve mntput() are run on nfsiod
rather than on rpciod, so that they don't deadlock when the resulting
umount calls rpc_shutdown_client(). Hence we specify that read, write and
commit calls must complete on nfsiod.
Ditto for NFSv4 open, lock, locku and close asynchronous calls.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

fs/nfs/direct.c

@@ -280,6 +280,7 @@ static ssize_t nfs_direct_read_schedule_segment(struct nfs_direct_req *dreq,
 		.rpc_client = NFS_CLIENT(inode),
 		.rpc_message = &msg,
 		.callback_ops = &nfs_read_direct_ops,
+		.workqueue = nfsiod_workqueue,
 		.flags = RPC_TASK_ASYNC,
 	};
 	unsigned int pgbase;
@@ -446,6 +447,7 @@ static void nfs_direct_write_reschedule(struct nfs_direct_req *dreq)
 	struct rpc_task_setup task_setup_data = {
 		.rpc_client = NFS_CLIENT(inode),
 		.callback_ops = &nfs_write_direct_ops,
+		.workqueue = nfsiod_workqueue,
 		.flags = RPC_TASK_ASYNC,
 	};
 
@@ -537,6 +539,7 @@ static void nfs_direct_commit_schedule(struct nfs_direct_req *dreq)
 		.rpc_message = &msg,
 		.callback_ops = &nfs_commit_direct_ops,
 		.callback_data = data,
+		.workqueue = nfsiod_workqueue,
 		.flags = RPC_TASK_ASYNC,
 	};
 
@@ -683,6 +686,7 @@ static ssize_t nfs_direct_write_schedule_segment(struct nfs_direct_req *dreq,
 		.rpc_client = NFS_CLIENT(inode),
 		.rpc_message = &msg,
 		.callback_ops = &nfs_write_direct_ops,
+		.workqueue = nfsiod_workqueue,
 		.flags = RPC_TASK_ASYNC,
 	};
 	size_t wsize = NFS_SERVER(inode)->wsize;

fs/nfs/nfs4proc.c

@@ -51,6 +51,7 @@
 
 #include "nfs4_fs.h"
 #include "delegation.h"
+#include "internal.h"
 #include "iostat.h"
 
 #define NFSDBG_FACILITY		NFSDBG_PROC
@@ -773,6 +774,7 @@ static int _nfs4_proc_open_confirm(struct nfs4_opendata *data)
 		.rpc_message = &msg,
 		.callback_ops = &nfs4_open_confirm_ops,
 		.callback_data = data,
+		.workqueue = nfsiod_workqueue,
 		.flags = RPC_TASK_ASYNC,
 	};
 	int status;
@@ -910,6 +912,7 @@ static int _nfs4_proc_open(struct nfs4_opendata *data)
 		.rpc_message = &msg,
 		.callback_ops = &nfs4_open_ops,
 		.callback_data = data,
+		.workqueue = nfsiod_workqueue,
 		.flags = RPC_TASK_ASYNC,
 	};
 	int status;
@@ -1315,6 +1318,7 @@ int nfs4_do_close(struct path *path, struct nfs4_state *state, int wait)
 		.rpc_client = server->client,
 		.rpc_message = &msg,
 		.callback_ops = &nfs4_close_ops,
+		.workqueue = nfsiod_workqueue,
 		.flags = RPC_TASK_ASYNC,
 	};
 	int status = -ENOMEM;
@@ -3235,6 +3239,7 @@ static struct rpc_task *nfs4_do_unlck(struct file_lock *fl,
 		.rpc_client = NFS_CLIENT(lsp->ls_state->inode),
 		.rpc_message = &msg,
 		.callback_ops = &nfs4_locku_ops,
+		.workqueue = nfsiod_workqueue,
 		.flags = RPC_TASK_ASYNC,
 	};
 
@@ -3419,6 +3424,7 @@ static int _nfs4_do_setlk(struct nfs4_state *state, int cmd, struct file_lock *f
 		.rpc_client = NFS_CLIENT(state->inode),
 		.rpc_message = &msg,
 		.callback_ops = &nfs4_lock_ops,
+		.workqueue = nfsiod_workqueue,
 		.flags = RPC_TASK_ASYNC,
 	};
 	int ret;

fs/nfs/read.c

@@ -177,6 +177,7 @@ static void nfs_read_rpcsetup(struct nfs_page *req, struct nfs_read_data *data,
 		.rpc_message = &msg,
 		.callback_ops = call_ops,
 		.callback_data = data,
+		.workqueue = nfsiod_workqueue,
 		.flags = RPC_TASK_ASYNC | swap_flags,
 	};
 

fs/nfs/write.c

@@ -803,6 +803,7 @@ static void nfs_write_rpcsetup(struct nfs_page *req,
 		.rpc_message = &msg,
 		.callback_ops = call_ops,
 		.callback_data = data,
+		.workqueue = nfsiod_workqueue,
 		.flags = flags,
 		.priority = priority,
 	};
@@ -1187,6 +1188,7 @@ static void nfs_commit_rpcsetup(struct list_head *head,
 		.rpc_message = &msg,
 		.callback_ops = &nfs_commit_ops,
 		.callback_data = data,
+		.workqueue = nfsiod_workqueue,
 		.flags = flags,
 		.priority = priority,
 	};