From 383ba71938519959be8e0b598ec658f0c211ff45 Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Tue, 19 Feb 2008 20:04:20 -0500 Subject: NFS: Fix a deadlock with lazy umount We can't allow rpc callback functions like task->tk_ops->rpc_call_prepare() and task->tk_ops->rpc_call_done() to call mntput() in any way, since that will cause a deadlock when the call to rpc_shutdown_client() attempts to wait on 'task' to complete. We can avoid the above deadlock by moving calls to mntput to task->tk_ops->rpc_release() callback, since at that time the task will be marked as completed, and so rpc_shutdown_client won't attempt to wait on it. Signed-off-by: Trond Myklebust --- fs/nfs/write.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) (limited to 'fs/nfs/write.c') diff --git a/fs/nfs/write.c b/fs/nfs/write.c index 80c61fdb272..69b4158d9a1 100644 --- a/fs/nfs/write.c +++ b/fs/nfs/write.c @@ -105,8 +105,11 @@ static void nfs_writedata_free(struct nfs_write_data *wdata) call_rcu_bh(&wdata->task.u.tk_rcu, nfs_writedata_rcu_free); } -void nfs_writedata_release(void *wdata) +void nfs_writedata_release(void *data) { + struct nfs_write_data *wdata = data; + + put_nfs_open_context(wdata->args.context); nfs_writedata_free(wdata); } @@ -816,7 +819,7 @@ static void nfs_write_rpcsetup(struct nfs_page *req, data->args.pgbase = req->wb_pgbase + offset; data->args.pages = data->pagevec; data->args.count = count; - data->args.context = req->wb_context; + data->args.context = get_nfs_open_context(req->wb_context); data->args.stable = NFS_UNSTABLE; if (how & FLUSH_STABLE) { data->args.stable = NFS_DATA_SYNC; @@ -1153,8 +1156,11 @@ int nfs_writeback_done(struct rpc_task *task, struct nfs_write_data *data) #if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4) -void nfs_commit_release(void *wdata) +void nfs_commit_release(void *data) { + struct nfs_write_data *wdata = data; + + put_nfs_open_context(wdata->args.context); nfs_commit_free(wdata); } @@ -1197,6 +1203,7 @@ static void nfs_commit_rpcsetup(struct list_head *head, /* Note: we always request a commit of the entire inode */ data->args.offset = 0; data->args.count = 0; + data->args.context = get_nfs_open_context(first->wb_context); data->res.count = 0; data->res.fattr = &data->fattr; data->res.verf = &data->verf; -- cgit v1.2.3