From c8da19b9866ea84e9ad1c369393ea95d54ee7845 Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Mon, 11 Feb 2013 19:01:21 -0500 Subject: [PATCH] NFSv4.1: Fix an ABBA locking issue with session and state serialisation Ensure that if nfs_wait_on_sequence() causes our rpc task to wait for an NFSv4 state serialisation lock, then we also drop the session slot. Signed-off-by: Trond Myklebust Cc: stable@vger.kernel.org --- fs/nfs/nfs4proc.c | 32 ++++++++++++++++++++------------ 1 file changed, 20 insertions(+), 12 deletions(-) diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c index 7cbf7aa6c634..cf252dfd91f8 100644 --- a/fs/nfs/nfs4proc.c +++ b/fs/nfs/nfs4proc.c @@ -1466,7 +1466,7 @@ static void nfs4_open_prepare(struct rpc_task *task, void *calldata) struct nfs4_state_owner *sp = data->owner; if (nfs_wait_on_sequence(data->o_arg.seqid, task) != 0) - return; + goto out_wait; /* * Check if we still need to send an OPEN call, or if we can use * a delegation instead. @@ -1501,6 +1501,7 @@ unlock_no_action: rcu_read_unlock(); out_no_action: task->tk_action = NULL; +out_wait: nfs4_sequence_done(task, &data->o_res.seq_res); } @@ -2179,7 +2180,7 @@ static void nfs4_close_prepare(struct rpc_task *task, void *data) dprintk("%s: begin!\n", __func__); if (nfs_wait_on_sequence(calldata->arg.seqid, task) != 0) - return; + goto out_wait; task->tk_msg.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_OPEN_DOWNGRADE]; calldata->arg.fmode = FMODE_READ|FMODE_WRITE; @@ -2201,16 +2202,14 @@ static void nfs4_close_prepare(struct rpc_task *task, void *data) if (!call_close) { /* Note: exit _without_ calling nfs4_close_done */ - task->tk_action = NULL; - nfs4_sequence_done(task, &calldata->res.seq_res); - goto out; + goto out_no_action; } if (calldata->arg.fmode == 0) { task->tk_msg.rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_CLOSE]; if (calldata->roc && pnfs_roc_drain(inode, &calldata->roc_barrier, task)) - goto out; + goto out_wait; } nfs_fattr_init(calldata->res.fattr); @@ -2220,8 +2219,12 @@ static void nfs4_close_prepare(struct rpc_task *task, void *data) &calldata->res.seq_res, task) != 0) nfs_release_seqid(calldata->arg.seqid); -out: dprintk("%s: done!\n", __func__); + return; +out_no_action: + task->tk_action = NULL; +out_wait: + nfs4_sequence_done(task, &calldata->res.seq_res); } static const struct rpc_call_ops nfs4_close_ops = { @@ -4452,12 +4455,10 @@ static void nfs4_locku_prepare(struct rpc_task *task, void *data) struct nfs4_unlockdata *calldata = data; if (nfs_wait_on_sequence(calldata->arg.seqid, task) != 0) - return; + goto out_wait; if (test_bit(NFS_LOCK_INITIALIZED, &calldata->lsp->ls_flags) == 0) { /* Note: exit _without_ running nfs4_locku_done */ - task->tk_action = NULL; - nfs4_sequence_done(task, &calldata->res.seq_res); - return; + goto out_no_action; } calldata->timestamp = jiffies; if (nfs4_setup_sequence(calldata->server, @@ -4465,6 +4466,11 @@ static void nfs4_locku_prepare(struct rpc_task *task, void *data) &calldata->res.seq_res, task) != 0) nfs_release_seqid(calldata->arg.seqid); + return; +out_no_action: + task->tk_action = NULL; +out_wait: + nfs4_sequence_done(task, &calldata->res.seq_res); } static const struct rpc_call_ops nfs4_locku_ops = { @@ -4612,7 +4618,7 @@ static void nfs4_lock_prepare(struct rpc_task *task, void *calldata) dprintk("%s: begin!\n", __func__); if (nfs_wait_on_sequence(data->arg.lock_seqid, task) != 0) - return; + goto out_wait; /* Do we need to do an open_to_lock_owner? */ if (!(data->arg.lock_seqid->sequence->flags & NFS_SEQID_CONFIRMED)) { if (nfs_wait_on_sequence(data->arg.open_seqid, task) != 0) { @@ -4632,6 +4638,8 @@ static void nfs4_lock_prepare(struct rpc_task *task, void *calldata) nfs_release_seqid(data->arg.open_seqid); out_release_lock_seqid: nfs_release_seqid(data->arg.lock_seqid); +out_wait: + nfs4_sequence_done(task, &data->res.seq_res); dprintk("%s: done!, ret = %d\n", __func__, data->rpc_status); } -- 2.20.1