From dc327ed4cd320be689596365372a3683208c3ba0 Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Sun, 6 May 2012 19:46:30 -0400 Subject: [PATCH] NFSv4: nfs_client_return_marked_delegations can't flush data Since even filemap_flush() needs to lock pages that are dirty, we cannot risk calling it from the state manager context. Therefore, we need to move the call to filemap_flush() to nfs_async_inode_return_delegation(). Signed-off-by: Trond Myklebust --- fs/nfs/delegation.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/fs/nfs/delegation.c b/fs/nfs/delegation.c index a19cb5ad6b13..bd3a9601d32d 100644 --- a/fs/nfs/delegation.c +++ b/fs/nfs/delegation.c @@ -316,6 +316,10 @@ static int __nfs_inode_return_delegation(struct inode *inode, struct nfs_delegat * nfs_client_return_marked_delegations - return previously marked delegations * @clp: nfs_client to process * + * Note that this function is designed to be called by the state + * manager thread. For this reason, it cannot flush the dirty data, + * since that could deadlock in case of a state recovery error. + * * Returns zero on success, or a negative errno value. */ int nfs_client_return_marked_delegations(struct nfs_client *clp) @@ -340,11 +344,9 @@ int nfs_client_return_marked_delegations(struct nfs_client *clp) server); rcu_read_unlock(); - if (delegation != NULL) { - filemap_flush(inode->i_mapping); + if (delegation != NULL) err = __nfs_inode_return_delegation(inode, delegation, 0); - } iput(inode); if (!err) goto restart; @@ -542,6 +544,8 @@ int nfs_async_inode_return_delegation(struct inode *inode, struct nfs_client *clp = server->nfs_client; struct nfs_delegation *delegation; + filemap_flush(inode->i_mapping); + rcu_read_lock(); delegation = rcu_dereference(NFS_I(inode)->delegation); -- GitLab